Partially redundant proneural function reveals the importance of timing during zebrafish olfactory neurogenesis.
Little is known about proneural gene function during olfactory neurogenesis in zebrafish. Here, we show that the zebrafish Atonal genes neurogenin1 (neurog1) and neurod4 are redundantly required for development of both early-born olfactory neurons (EONs) and later-born olfactory sensory neurons (OSNs). We show that neurod4 expression is initially absent in neurog1 mutant embryos but recovers and is sufficient for the delayed development of OSN. By contrast, EON numbers are significantly reduced in neurog1 mutant embryos despite the recovery of neurod4 expression. Our results suggest that a shortened time window for EON development causes this reduction; the last S-phase of EON is delayed in neurog1 mutant embryos but mutant EONs are all post-mitotic at the same stage as EONs in wild-type embryos. Finally, we show that expression of certain genes, such as robo2, is never detected in neurog1 mutant EONs. Failure of robo2 expression to recover correlates with defects in the fasciculation of neurog1 mutant olfactory axonal projections and in the organisation of proto-glomeruli because projections arrive at the olfactory bulb that are reminiscent of those in robo2 mutant embryos. We conclude that the duration of proneural expression in EON progenitors is crucial for correct development of the zebrafish olfactory system.


Regulation of mercury resistance in the crenarchaeote Sulfolobus solfataricus.
Mercuric ion, Hg(II), inactivates generalized transcription in the crenarchaeote Sulfolobus solfataricus. Metal challenge simultaneously derepresses transcription of mercuric reductase (merA) by interacting with the archaeal transcription factor aMerR. Northern blot and primer extension analyses identified two additional Hg(II)-inducible S. solfataricus genes, merH and merI (SSO2690), located on either side of merA. Transcription initiating upstream of merH at promoter merHp was metal inducible and extended through merA and merI, producing a merHAI transcript. Northern analysis of a merRA double mutant produced by linear DNA recombination demonstrated merHp promoter activity was dependent on aMerR to overcome Hg(II) transcriptional inhibition. Unexpectedly, in a merA disruption mutant, the merH transcript was transiently induced after an initial period of Hg(II)-mediated transcription inhibition, indicating continued Hg(II) detoxification. Metal challenge experiments using mutants created by markerless exchange verified the identity of the MerR binding site as an inverted repeat (IR) sequence overlapping the transcription factor B binding recognition element of merHp. The interaction of recombinant aMerR with merHp DNA, studied using electrophoretic mobility shift analysis, demonstrated that complex formation was template specific and dependent on the presence of the IR sequence but insensitive to Hg(II) addition and site-specific IR mutations that relieved in vivo merHp repression. Despite containing a motif resembling a distant ArsR homolog, these results indicate aMerR remains continuously DNA bound to protect and coordinate Hg(II)-responsive control over merHAI transcription. The new genetic methods developed in this work will promote experimental studies on S. solfataricus and other Crenarchaeota.


Migration and stopover in a small pelagic seabird, the Manx shearwater Puffinus puffinus: insights from machine learning.
The migratory movements of seabirds (especially smaller species) remain poorly understood, despite their role as harvesters of marine ecosystems on a global scale and their potential as indicators of ocean health. Here we report a successful attempt, using miniature archival light loggers (geolocators), to elucidate the migratory behaviour of the Manx shearwater Puffinus puffinus, a small (400 g) Northern Hemisphere breeding procellariform that undertakes a trans-equatorial, trans-Atlantic migration. We provide details of over-wintering areas, of previously unobserved marine stopover behaviour, and the long-distance movements of females during their pre-laying exodus. Using salt-water immersion data from a subset of loggers, we introduce a method of behaviour classification based on Bayesian machine learning techniques. We used both supervised and unsupervised machine learning to classify each bird's daily activity based on simple properties of the immersion data. We show that robust activity states emerge, characteristic of summer feeding, winter feeding and active migration. These can be used to classify probable behaviour throughout the annual cycle, highlighting the likely functional significance of stopovers as refuelling stages.


Androgen regulates ADAMTS15 gene expression in prostate cancer cells.
Prostate cancer is a major cause of mortality, largely as a consequence of metastases and transformation to androgen-independent growth. Metalloproteinases are implicated in cancer progression. A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) are expressed in prostate cancer cells, with ADAMTS-1 and ADAMTS-15 being the most abundant. ADAMTS-15 but not ADAMTS-1 expression was downregulated by androgen in LNCaP prostate cancer cells, possibly through androgen response elements associated with the gene. ADAMTS-15 expression is predictive for survival in breast cancer, and the situation may be similar in prostate cancer, as androgen independence is usually due to aberrant signaling through its receptor.


Operative management of acetabular fractures in Oxford.
We reviewed the epidemiology and complications of 79 patients who had operative treatment for an acetabular fracture undertaken at this hospital, in the first 5 years of a pelvic and acetabular fracture service. The median Injury Severity Score was 18 (range, 9-41). Sixty-five patients (82%) had an important injury of at least one other system. Eighteen patients (23%) had a sciatic nerve injury on presentation. Thirty-seven patients (47%) had a post-operative complication, but this did not affect the outcome in the majority. The re-operation rate was 5%.Seventy-four patients (94%) had clinical and radiological follow-up for a mean of 2.6 years. Fifty-five patients (74%) had a good or excellent result, which was associated with early operation and an anatomical reduction. Poor outcome was associated with delay to surgery, failure to achieve or maintain reduction, and femoral head damage at the time of injury.


Phenotypic variation in infants, not adults, reflects genotypic variation among chimpanzees and bonobos.
Studies comparing phenotypic variation with neutral genetic variation in modern humans have shown that genetic drift is a main factor of evolutionary diversification among populations. The genetic population history of our closest living relatives, the chimpanzees and bonobos, is now equally well documented, but phenotypic variation among these taxa remains relatively unexplored, and phenotype-genotype correlations are not yet documented. Also, while the adult phenotype is typically used as a reference, it remains to be investigated how phenotype-genotye correlations change during development. Here we address these questions by analyzing phenotypic evolutionary and developmental diversification in the species and subspecies of the genus Pan. Our analyses focus on the morphology of the femoral diaphysis, which represents a functionally constrained element of the locomotor system. Results show that during infancy phenotypic distances between taxa are largely congruent with non-coding (neutral) genotypic distances. Later during ontogeny, however, phenotypic distances deviate from genotypic distances, mainly as an effect of heterochronic shifts between taxon-specific developmental programs. Early phenotypic differences between Pan taxa are thus likely brought about by genetic drift while late differences reflect taxon-specific adaptations.


The aetiology and trajectory of anabolic-androgenic steroid use initiation: a systematic review and synthesis of qualitative research.
To our knowledge, there has never been a systematic review and synthesis of the qualitative literature on the trajectory and aetiology of nonmedical anabolic-androgenic steroid (AAS) use. We systematically reviewed and synthesized qualitative literature gathered from searches in PsycINFO, PubMed, ISI Web of Science, Google Scholar, and reference lists of relevant literature to investigate AAS users' ages of first use and source(s), history prior to use, and motives/drives for initiating use. We adhered to the recommendations of the UK Economic and Social Research Council's qualitative research synthesis manual and the PRISMA guidelines. A total of 44 studies published between 1980 and 2014 were included in the synthesis. Studies originated from 11 countries: the United States (n = 18), England (n = 8), Australia (n = 4), Sweden (n = 4), both England and Wales (n = 2), and Scotland (n = 2). One study each originated from Brazil, Bulgaria, Canada, France, Great Britain, and Norway. The majority of AAS users initiated use before age 30. Sports participation (particularly power sports), negative body image, and psychological disorders such as depression preceded initiation of AAS use for most users. Sources of first AAS were mainly users' immediate social networks and the illicit market. Enhanced sports performance, appearance, and muscle/strength were the paramount motives for AAS use initiation. Our findings elucidate the significance of psychosocial factors in AAS use initiation. The proliferation of AAS on the illicit market and social networks demands better ways of dealing with the global public health problem of AAS use.


Venous-arterial CO2 difference in children with sepsis and its correlation with myocardial dysfunction.
Objective: This study aimed to determine the association between venous-arterial CO2 difference (Pv-aCO2) and clinical outcomes of interest in children with severe sepsis and septic shock. Design: An analytical observational study of a prospective cohort was conducted. Setting: The study was carried out from January 2015 to January 2018 in the pediatric intensive care unit of a referral hospital. Materials and methods: Of a total of 1159 patients who were admitted to pediatric critical care, 375 had severe sepsis and septic shock, of which 67 fulfilled the inclusion criteria. Arterial and venous gases were drawn simultaneously with a transthoracic echocardiogram, Pv-aCO2, and other measures of tissue perfusion such as arterial lactate, venous, and evolution to multiple organ failure. Measurements and main results: Half (53.7%) of the patients were under 24 months old, with a slight predominance of male patients. The main site of infection was the lungs in 56% of the cases, with a 91.2% survival rate. Patients who died had a higher venous lactate level (interquartile range 16.2-33.6, p = 0.02). However, there was no correlation between myocardial dysfunction seen on echocardiogram and a Pv-aCO2 greater than 6 mm Hg in children with severe sepsis and septic shock (r = 0.13). Pv-aCO2 and central venous saturation had low sensitivity to detect multiple organ failure and poor correlation with the number of compromised systems (r = 0.8). Conclusion: Pv-aCO2 was not associated with myocardial dysfunction, measured by echocardiogram, in children with severe sepsis and septic shock. It also did not correlate with the number of organs involved or mortality.


The English Sweating Sickness: Out of Sight, Out of Mind?
In this paper we aim to add additional knowledge regarding the occurrence, origin and epidemiological features of the English sweating sickness. The English sweating sickness raged in five devastating epidemics with mortality rates between 30 and 50% between 1485 and 1551 throughout England, and on one occasion also affected mainland Europe, in 1529. The Picardy sweat, generally considered as the English sweating sickness' lesser deadly successor, flared up in France in 1718 and caused 196 localized outbreaks with varying severity all over France and neighboring countries up to 1861. The English sweating sickness has been the subject of numerous attempts to define its origin, but so far all efforts have failed due to lack of material, DNA or RNA, that - using modern techniques and knowledge - could shed light on its cause. Although the time frame in which the English sweating sickness occurred and the geographical spread of the outbreaks is generally known, we will demonstrate here that there was more to it than meets the eye. We found reports of cases of sweating sickness in years before, after and between the 1485, 1508, 1517, 1529 and 1551 epidemics, as well as reports of sweating sickness in Italy and Spain. In spite of the fact that the English sweating sickness apparently has not caused casualties for a more than a century now, we suggest that -given the right circumstances- the possibility of re-emergence might still exist. The fact that up until today we have no indication concerning the causal pathogen of the English sweating sickness is certainly not re-assuring.


An orderly personality partially explains the link between trait disgust and political conservatism.
Individuals who are more easily disgusted tend to be more politically conservative. Individuals who have a preference for order also tend to be more politically conservative. In the present research, we hypothesised that these three variables are psychologically interrelated. Specifically, trait disgust encourages a generalised search for order, which, in turn, encourages the endorsement of political positions that aim to maintain societal order. Taking an individual differences approach, we operationalised the preference for order via Orderliness, one aspect of the Big Five trait Conscientiousness. Across six samples (total N = 1485), participants completed measures of trait disgust, aspect/trait personality, and political orientation. Analyses revealed that Orderliness was a consistent mediator of the association between trait disgust and conservatism. Analyses of subscales of disgust revealed preliminary evidence that Orderliness most consistently mediated the relationships between Contamination, Pathogen, and Sexual disgust and conservatism. These data suggest that disgust-sensitive people extend their preference for order in the physical environment (e.g. tidying up one's room) to the sociopolitical environment (e.g. strengthening traditional norms). The present findings illustrate one way in which emotional, cognitive, and personality processes work together to influence political orientation.


Ten years on: a follow-up review of ERP research in attention-deficit/hyperactivity disorder.
This article reviews the event-related potential (ERP) literature in relation to attention-deficit/hyperactivity disorder (AD/HD) over the years 2002-2012. ERP studies exploring various aspects of brain functioning in children and adolescents with AD/HD are reviewed, with a focus on group effects and interpretations in the domains of attention, inhibitory control, performance monitoring, non-pharmacological treatments, and ERP/energetics interactions. There has been a distinct shift in research intensity over the past 10 years, with a large increase in ERP studies conducted in the areas of inhibitory control and performance monitoring. Overall, the research has identified a substantial number of ERP correlates of AD/HD. Robust differences from healthy controls have been reported in early orienting, inhibitory control, and error-processing components. These data offer potential to improve our understanding of the specific brain dysfunction(s) which contribute to the disorder. The literature would benefit from a more rigorous approach to clinical group composition and consideration of age effects, as well as increased emphasis on replication and extension studies using exacting participant, task, and analysis parameters.


Hsp90 potentiates the rapid evolution of new traits: drug resistance in diverse fungi.
Hsp90 is a molecular chaperone for many signal transducers and may influence evolution by releasing previously silent genetic variation in response to environmental change. In fungi separated by approximately 800 million years of evolution, Hsp90 potentiated the evolution of drug resistance in a different way, by enabling new mutations to have immediate phenotypic consequences. Resistance was abrogated by Hsp90 inhibitors and by febrile temperatures, suggesting new therapeutic strategies and a clinical benefit of fever. During selection in a human host, drug resistance that was initially Hsp90-dependent evolved toward independence. Thus, Hsp90 can act in diverse ways to couple environmental contingency to the emergence and fixation of new traits.


Comparative kinematics of the forelimb during swimming in red-eared slider (Trachemys scripta) and spiny softshell (Apalone spinifera) turtles.
Softshell turtles (Family Trionychidae) possess extensive webbing between the digits of the manus, suggesting that the forelimb may serve as an effective thrust generator during aquatic locomotion. However, the hindlimb has previously been viewed as the dominant propulsive organ in swimming freshwater turtles. To evaluate the potential role of the forelimb in thrust production during swimming in freshwater turtles, we compared the forelimb morphology and three-dimensional forelimb kinematics of a highly aquatic trionychid turtle, the spiny softshell Apalone spinifera, and a morphologically generalized emydid turtle, the red-eared slider Trachemys scripta. Spiny softshells possess nearly twice as much forelimb surface area as sliders for generating drag-based thrust. In addition, although both species use drag-based propulsion, several aspects of forelimb kinematics differ significantly between these species. During the thrust phase of the forelimb cycle, spiny softshells hold the elbow and wrist joints significantly straighter than sliders, thereby further increasing the surface area of the limb that can move water posteriorly and increasing the velocity of the distal portion of the forelimb. These aspects of swimming kinematics in softshells should increase forelimb thrust production and suggest that the forelimbs make more substantial contributions to forward thrust in softshell turtles than in sliders. Spiny softshells also restrict forelimb movements to a much narrower dorsoventral and anteroposterior range than sliders throughout the stroke, thereby helping to minimize limb movements potentially extraneous to forward thrust production. These comparisons demonstrate considerable diversity in the forelimb kinematics of turtles that swim using rowing motions of the limbs and suggest that the evolution of turtle forelimb mechanics produced a variety of contrasting solutions for aquatic specialization.


Implementation of a new CSF dynamic device: a multicenter feasibility study in 562 patients.
The cerebrospinal fluid (CSF) infusion test is frequently used when selecting hydrocephalus patients for shunt surgery. Very little has been reported regarding adverse events. We present a prospective feasibility study. Standardized devices for measuring CSF dynamics were built and 562 patients investigated: Needles were placed by lumbar puncture (LP). An automatic CSF infusion protocol was performed. Course of events during the investigation as well as adverse events were registered. Preoperative evaluation of normal-pressure hydrocephalus was the most common indication (63%), followed by evaluation of shunt function (23%) and intracranial pressure recordings (14%). The LP was successfully performed in all but nine cases with 24 patients (4.3%) reporting major discomfort. Ringer infusion was performed in 474 investigations, and a valid measurement of the outflow resistance was received in 439 (93%). During the infusion phase, 17 (4%) patients reported severe headache. Infusion volume was significantly higher in patients having subjective symptoms during the infusion phase compared with those without adverse events. During 269 preoperative CSF tap tests, six (2%) patients had severe headache. Post-investigational headache was reported by 83 (15%) patients at the 24-h follow-up. No serious adverse events were observed. Infusion testing was safe and without serious adverse events with a high rate of successful procedures. The investigation was associated with expected mild to moderate discomfort.


Policy challenges for the pediatric rheumatology workforce: Part III. the international situation.
Survival dominates current pediatric global health priorities. Diseases of poverty largely contribute to overall mortality in children under 5 years of age. Infectious diseases and injuries account for 75% of cause-specific mortality among children ages 5-14 years. Twenty percent of the world's population lives in extreme poverty (income below US $1.25/day). Within this population, essential services and basic needs are not met, including clean water, sanitation, adequate nutrition, shelter, access to health care, medicines and education. In this context, musculoskeletal disease comprises 0.1% of all-cause mortality in children ages 5-14 years. Worldwide morbidity from musculoskeletal disease remains generally unknown in the pediatric age group. This epidemiologic data is not routinely surveyed by international agencies, including the World Health Organization. The prevalence of pediatric rheumatic diseases based on data from developed nations is in the range of 2,500 - 3,000 cases per million children. Developing countries' needs for musculoskeletal morbidity are undergoing an epidemiologic shift to chronic conditions, as leading causes of pediatric mortality are slowly quelled.A global crisis of health care providers and human resources stems from insufficient workforce production, inability to retain workers in areas of greatest need, distribution disparity and poor management of both health care systems and health workforce. Internationally, the pediatric rheumatology workforce will also be in very short supply for the foreseeable future relative to projected demand. Physician extenders are an essential resource to meet this demand in underserved regions. They can be trained in common aspects of musculoskeletal medicine and rheumatic conditions. Innovative strategies have been introduced in the United Kingdom to address musculoskeletal medicine educational deficiencies. Telemedicine offers an important capacity to improve access to care despite distance. Regulatory flexibility may allow realignment of clinical responsibilities through existing and future governmental or non-governmental credentialing organizations. This review explores a variety of creative approaches which hold promise to improve patient access to care.


Concentrations and sources of polycyclic aromatic hydrocarbons in surface coastal sediments of the northern Gulf of Mexico.
Coastal sediments in the northern Gulf of Mexico have a high potential of being contaminated by petroleum hydrocarbons, such as polycyclic aromatic hydrocarbons (PAHs), due to extensive petroleum exploration and transportation activities. In this study we evaluated the spatial distribution and contamination sources of PAHs, as well as the bioavailable fraction in the bulk PAH pool, in surface marsh and shelf sediments (top 5 cm) of the northern Gulf of Mexico. PAH concentrations in this region ranged from 100 to 856 ng g-1, with the highest concentrations in Mississippi River mouth sediments followed by marsh sediments and then the lowest concentrations in shelf sediments. The PAH concentrations correlated positively with atomic C/N ratios of sedimentary organic matter (OM), suggesting that terrestrial OM preferentially sorbs PAHs relative to marine OM. PAHs with 2 rings were more abundant than those with 5-6 rings in continental shelf sediments, while the opposite was found in marsh sediments. This distribution pattern suggests different contamination sources between shelf and marsh sediments. Based on diagnostic ratios of PAH isomers and principal component analysis, shelf sediment PAHs were petrogenic and those from marsh sediments were pyrogenic. The proportions of bioavailable PAHs in total PAHs were low, ranging from 0.02% to 0.06%, with higher fractions found in marsh than shelf sediments. PAH distribution and composition differences between marsh and shelf sediments were influenced by grain size, contamination sources, and the types of organic matter associated with PAHs. Concentrations of PAHs in the study area were below effects low-range, suggesting a low risk to organisms and limited transfer of PAHs into food web. From the source analysis, PAHs in shelf sediments mainly originated from direct petroleum contamination, while those in marsh sediments were from combustion of fossil fuels.


Interfacially active polydopamine for nanoparticle stabilized nanocapsules in a one-pot assembly strategy toward efficient drug delivery.
Nanoscale colloidal capsules are promising drug delivery carriers currently while the demand for multiple-step syntheses and the difficulties in achieving high capsule stability are key obstacles that have greatly restricted their development. Herein, we report a polydopamine (PDA) nanoparticle stabilized nanocapsule as a drug delivery system based on the combination of nanoparticle formation and capsule assembly/stabilization in one pot. In this system, an arginine modified linoleic acid nanoemulsion was employed as the template for the in situ generation/assembly of interfacially active PDA nanoparticles, while directional interaction pairs of carboxylate-guanidine and amino-PDA linked by arginine are involved in the assembly process. The nanocapsules possess an average size of 100 nm, high stability in biological media, and efficient lipophilic transfer of the loaded lipophilic cargo. Notably, the high biocompatibility of the nanocapsules and the non-endocytotic delivery to the cytosol of cancer cells were demonstrated in vitro. Furthermore, the efficient delivery of paclitaxel, as well as paclitaxel/doxorubicin dual cargo, was realized, resulting in the high inhibition of cancer cells. Altogether, the PDA nanoparticle stabilized nanocapsules open new opportunities for the development of promising nanocapsule platforms for biomedical delivery.


Sex-specific HDL cholesterol changes with weight loss and their association with anthropometric variables: the LIFE study.
Decrease in the level of high-density lipoprotein cholesterol (HDLC) has been observed in women who start dieting, but not in men. Patterns of HDLC change during intentional weight loss through 30-months of follow-up, and their association with changes in anthropometric measurements were examined in obese women (N = 112) and men (N = 100). Missing HDLC values at 6-, 12-, 18-, and 30-month follow-up (N = 16, 34, 55, and 50, respectively) due to dropout were imputed by multiple imputation. Mean ages and BMIs of subjects at baseline were 47.2 years and 34.8 kg/m(2) for women, and 50.4 years and 35.0 kg/m(2) for men. On average, participants lost weight steadily for 12 months, followed by slow regain. During the first 6 months, HDLC decreased significantly in women (-4.1 mg/dl, P = 0.0007), but not in men. Significant HDLC increases were observed in both men and women from 6- to 12-month follow-up. HDLC changes in women were positively associated with changes in hip circumference from baseline to 12-month independent of changes in triglycerides (TG), glucose, and insulin. Rapid decrease of predominantly subcutaneous fat in the femoral and gluteal area might be associated with HDLC decrease in women during initial weight loss.


Characterization and implications of intradecadal variations in length of day.
Variations in Earth's rotation (defined in terms of length of day) arise from external tidal torques, or from an exchange of angular momentum between the solid Earth and its fluid components. On short timescales (annual or shorter) the non-tidal component is dominated by the atmosphere, with small contributions from the ocean and hydrological system. On decadal timescales, the dominant contribution is from angular momentum exchange between the solid mantle and fluid outer core. Intradecadal periods have been less clear and have been characterized by signals with a wide range of periods and varying amplitudes, including a peak at about 6 years (refs 2-4). Here, by working in the time domain rather than the frequency domain, we show a clear partition of the non-atmospheric component into only three components: a decadally varying trend, a 5.9-year period oscillation, and jumps at times contemporaneous with geomagnetic jerks. The nature of the jumps in length of day leads to a fundamental change in what class of phenomena may give rise to the jerks, and provides a strong constraint on electrical conductivity of the lower mantle, which can in turn constrain its structure and composition.


A Useful Selective Bactericidal Property of Tergitol-7.
Starch tryptone agar containing 1 : 20,000 Tergitol-7 was successfully sterilized in the Arnold by one 30-minute heating period. Decreasing the concentration to 1 : 30,000 resulted in 4 per cent failures. A concentration of 1 : 20,000 in the cold killed spores of B. mycoides and an unidentified heat-resistant bacillus but failed to kill spores of B. subtilis. Concentrations of 1 : 30,000 permitted growth after sterilization of all species of Streptomyces which were tested, while concentrations of 1 : 20,000 permitted growth of all species but one. Concentrations of 1 : 20,000 did not inhibit the growth of selected species of Penicillium and Aspergillus or of Staph. aureus. Concentrations as high as 1 : 10,000 did not inhibit the growth of E. coli.


C60 in water: nanocrystal formation and microbial response.
Upon contact with water, under a variety of conditions, C60 spontaneously forms a stable aggregate with nanoscale dimensions (d = 25-500 nm), termed here "nano-C60". The color, hydrophobicity, and reactivity of individual C60 are substantially altered in this aggregate form. Herein, we provide conclusive lines of evidence demonstrating that in solution these aggregates are crystalline in order and remain as underivatized C60 throughout the formation/stabilization process that can later be chemically reversed. Particle size can be affected by formation parameters such as rates and the pH of the water addition. Once formed, nano-C60 remains stable in solution at or below ionic strengths of 0.05 I for months. In addition to demonstrating aggregate formation and stability over a wide range of conditions, results suggest that prokaryotic exposure to nano-C60 at relatively low concentrations is inhibitory, indicated by lack of growth (> or = 0.4 ppm) and decreased aerobic respiration rates (4 ppm). This work demonstrates the fact that the environmental fate, distribution, and biological risk associated with this important class of engineered nanomaterials will require a model that addresses not only the properties of bulk C60 but also that of the aggregate form generated in aqueous media.


Impacts of warming on phytoplankton abundance and phenology in a typical tropical marine ecosystem.
In the tropics, thermal stratification (during warm conditions) may contribute to a shallowing of the mixed layer above the nutricline and a reduction in the transfer of nutrients to the surface lit-layer, ultimately limiting phytoplankton growth. Using remotely sensed observations and modelled datasets, we study such linkages in the northern Red Sea (NRS) - a typical tropical marine ecosystem. We assess the interannual variability (1998-2015) of both phytoplankton biomass and phenological indices (timing of bloom initiation, duration and termination) in relation to regional warming. We demonstrate that warmer conditions in the NRS are associated with substantially weaker winter phytoplankton blooms, which initiate later, terminate earlier and are shorter in their overall duration (~ 4 weeks). These alterations are directly linked with the strength of atmospheric forcing (air-sea heat fluxes) and vertical stratification (mixed layer depth [MLD]). The interannual variability of sea surface temperature (SST) is found to be a good indicator of phytoplankton abundance, but appears to be less important for predicting bloom timing. These findings suggest that future climate warming scenarios may have a two-fold impact on phytoplankton growth in tropical marine ecosystems: 1) a reduction in phytoplankton abundance and 2) alterations in the timing of seasonal phytoplankton blooms.


Liver fat accumulation is associated with reduced hepatic insulin extraction and beta cell dysfunction in healthy older individuals.
There is a well-established association between type 2 diabetes and non-alcoholic fatty liver disease (NAFLD) secondary to excess accumulation of intrahepatic lipid (IHL), but the mechanistic basis for this association is unclear. Emerging evidence suggests that in addition to being associated with insulin resistance, NAFLD may be associated with relative beta-cell dysfunction. We sought to determine the influence of liver fat on hepatic insulin extraction and indices of beta-cell function in a cohort of apparently healthy older white adults. We performed a cross-sectional analysis of 70 healthy participants in the Hertfordshire Physical Activity Trial (39 males, age 71.3 ± 2.4 years) who underwent oral glucose tolerance testing with glucose, insulin and C-Peptide levels measured every 30 minutes over two hours. The areas under the concentration curve for glucose, insulin and C-Peptide were used to quantify hepatic insulin extraction (HIE), the insulinogenic index (IGI), the C-Peptide increment (CGI), the Disposition Index (DI) and Adaptation Index (AI). Visceral fat was quantified with magnetic resonance (MR) imaging and IHL with MR spectroscopy. Insulin sensitivity was measured with the Oral Glucose Insulin Sensitivity (OGIS) model. 29 of 70 participants (41%) exceeded our arbitrary threshold for NAFLD, i.e. IHL >5.5%. Compared to those with normal IHL, those with NAFLD had higher weight, BMI, waist and MR visceral fat, with lower insulin sensitivity and hepatic insulin extraction. Alcohol consumption, age, HbA1c and alanine aminotransferase (ALT) levels were similar in both groups. Insulin and C-Peptide excursions after oral glucose loading were higher in the NAFLD group, but the CGI and AI were significantly lower, indicating a relative defect in beta-cell function that is only apparent when C-Peptide is measured and when dynamic changes in glucose levels and also insulin sensitivity are taken into account. There was no difference in IGI or DI between the groups. Although increased IHL was associated with greater insulin secretion, modelled parameters suggested relative beta-cell dysfunction with NAFLD in apparently healthy older adults, which may be obscured by reduced hepatic insulin extraction. Further studies quantifying pancreatic fat content directly and its influence on beta cell function are warranted. ISRCTN60986572.


Inhibition of interleukin-8 reduces tumorigenesis of human non-small cell lung cancer in SCID mice.
The salient feature of solid tumor growth is the strict dependence on local angiogenesis. We have previously demonstrated that IL-8 is an angiogenic factor present in freshly isolated specimens of human non-small cell lung cancer (NSCLC). Using a model of human NSCLC tumorigenesis in SCID mice, we now report that IL-8 acts as a promoter of human NSCLC tumor growth through its angiogenic properties. Passive immunization with neutralizing antibodies to IL-8 resulted in more than 40% reduction in tumor size and was associated with a decline in tumor-associated vascular density and angiogenic activity. IL-8 did not act as an autocrine growth factor for NSCLC proliferation. The reduction in primary tumor size in response to neutralizing antibodies to IL-8 was also accompanied by a trend toward a decrease in spontaneous metastasis to the lung. These data support the notion that IL-8 plays a significant role in mediating angiogenic activity during tumorigenesis of human NSCLC, thereby offering a potential target for immunotherapy against solid tumors.


Holistic Analysis Enhances the Description of Metabolic Complexity in Dietary Natural Products.
In the field of food and nutrition, complex natural products (NPs) are typically obtained from cells/tissues of diverse organisms such as plants, mushrooms, and animals. Among them, edible fruits, grains, and vegetables represent most of the human diet. Because of an important dietary dependence, the comprehensive metabolomic analysis of dietary NPs, performed holistically via the assessment of as many metabolites as possible, constitutes a fundamental building block for understanding the human diet. Both mass spectrometry (MS) and nuclear magnetic resonance (NMR) are important complementary analytic techniques, covering a wide range of metabolites at different concentrations. Particularly, 1-dimensional 1H-NMR offers an unbiased overview of all metabolites present in a sample without prior knowledge of its composition, thereby leading to an untargeted analysis. In the past decade, NMR-based metabolomics in plant and food analyses has evolved considerably. The scope of the present review, covering literature of the past 5 y, is to address the relevance of 1H-NMR–based metabolomics in food plant studies, including a comparison with MS-based techniques. Major applications of NMR-based metabolomics for the quality control of dietary NPs and assessment of their nutritional values are presented.


Localization of myosin, actin, and tropomyosin in rat intestinal epithelium: immunohistochemical studies at the light and electron microscope levels.
Myosin, tropomyosin, and actin were localized in the epithelial cells of rat intestine by means of specific antibodies to chicken gizzard smooth muscle myosin, tropomyosin, and actin by immunohistochemical studies at both the light and electron microscope levels (unlabeled antibody enzyme technique). The pattern of antibody staining was the following (a) Anti-actin was associated with the microfilament bundles of the microvilli in their entire length, as well as with the microfilament network in the terminal web. (b) Anti-myosin was concentrated along the rootlets of the microvillar microfilament bundles and within the filamentous feltwork forming the terminal web. (c) Anti-tropomyosin showed a distribution similar to that of anti-myosin. In addition, the three antibodies also labeled the subplasmalemmal web underneath the cell membrane bordering on the basal lamina. Utilizing the above ultrastructural findings, we wish to propose a functional model of microvillar contraction.


Changes in cystic fibrosis sputum microbiology in the United States between 1995 and 2008.
The study objective was to identify changes in cystic fibrosis (CF) sputum microbiology over 13 years. This study recruited a contemporary cohort of CF patients meeting similar eligibility criteria as the 520 subjects in the Phase 3 trials of inhaled tobramycin (historical cohort). Subjects submitted a single sputum specimen to a centralized laboratory for culture and susceptibility testing. Data were summarized and cross-sectional prevalence estimates were compared between cohorts. Exploratory analyses examined associations between recent antibiotic exposures and resistance prevalence. Sputum samples from 267 subjects from 33 US CF centers were submitted for testing. A total of 656 Pseudomonas aeruginosa isolates were identified from 253 culture-positive subjects. Comparison between cohorts revealed an increase in the prevalence of subjects with tobramycin resistant (11.8% vs. 30.4%, P < 0.001) and amikacin resistant (24.2% vs. 42.7%, P < 0.001) P. aeruginosa. Prevalence of ciprofloxacin resistance was similar (34.4% vs. 33.6%, P = 0.81). Within the contemporary cohort, potential associations between recent antibiotic exposures and prevalence of P. aeruginosa resistance were examined; findings included that exposure to intravenous carbapenems was significantly associated with aztreonam resistance, meropenem resistance, and multidrug resistance (P = 0.0002, P = 0.0003, and P = 0.0002, respectively). Prevalences of Staphylococcus aureus, methicillin-resistant S. aureus, Stenotrophomonas maltophilia, and Achromobacter xylosoxidans were also increased in the contemporary cohort. We identified important changes in the patterns of CF airway microbiology, including increased aminoglycoside resistance and prevalence of other antibiotic resistant organisms. These changes are concerning to clinicians caring for individuals with CF because they impact treatment options. These data point to a critical need to develop new antimicrobials for CF.


Enhanced cloning efficiency of mouse bone marrow macrophage progenitors correlates with increased content of CSF-1 receptor of their progeny at low oxygen tension.
Mononuclear phagocytes are located in every tissue of metazoan organisms. In this extravascular space, they are designated as macrophages and are known to sense and process many signals including the local oxygen tension (PO2), which ranges from 150 mmHg at the lung apices to around 40 mmHg in mixed venous blood and most organs, and to less than 10 mmHg in tissues where long-term and dynamic remodeling processes occur. Most tissue macrophages survive and maintain their differentiated status within an environment bathed by colony-stimulating factor (CSF)-1 through the CSF-1 receptor, encoded by the Csf1r gene. In order to investigate the mRNA expression profile of macrophages as a function of PO2, we developed an in vitro model in which monocyte-derived macrophages were generated from mouse bone marrow progenitor cells grown and maintained under low (36 mmHg) or atmospheric (142 mmHg) PO2, in the presence of L929-conditioned medium (L-CM) as a source of CSF-1. We show that CSF-1-reactive C57BL/6 bone marrow cells displayed an increased cloning efficiency under a PO2 of 36, compared with 142 mmHg. Furthermore, we provide evidence of the overexpression of both CSF-1 receptor protein and mRNA by mouse monocyte-derived macrophages generated from bone marrow under low PO2.


Recombinant human pentraxin-2 therapy in patients with idiopathic pulmonary fibrosis: safety, pharmacokinetics and exploratory efficacy.
Abnormal fibrogenic repair response upon alveolar injury is believed to play an important role in the pathogenesis of idiopathic pulmonary fibrosis (IPF). PRM-151 (recombinant human pentraxin-2, also known as serum amyloid P), has been shown to reduce fibrosis in preclinical lung fibrosis models, and was well tolerated with a favourable pharmacokinetic profile in an earlier single-dose phase I study.A randomised, double-blind, placebo-controlled, multiple ascending dose trial was performed to assess the tolerability and pharmacokinetic and pharmacodynamic characteristics of multiple doses of PRM-151 in IPF patients. Subjects in three successive cohorts (1, 5, or 10 mg·kg(-1) versus placebo) received intravenous study drug on days 1, 3, 5, 8 and 15, and were followed-up to day 57.PRM-151 was well tolerated at all dose levels, with no serious adverse reactions. Administration of PRM-151 resulted in two- to eight-fold dose-dependent increases in circulating pentraxin-2 levels. Forced vital capacity and 6-min walk test showed trends towards improvement in the combined PRM-151 dose groups. On high-resolution computed tomography scans, stable or improved lung volume unoccupied by interstitial lung abnormality was noted in some PRM-151 subjects compared to placebo subjects on day 57.The efficacy of PRM-151 in IPF remains to be investigated in dedicated future trials.


Shunting inhibition does not have a divisive effect on firing rates.
Shunting inhibition, a conductance increase with a reversal potential close to the resting potential of the cell, has been shown to have a divisive effect on subthreshold excitatory postsynaptic potential amplitudes. It has therefore been assumed to have the same divisive effect on firing rates. We show that shunting inhibition actually has a subtractive effect on the firing rate in most circumstances. Averaged over several interspike intervals, the spiking mechanism effectively clamps the somatic membrane potential to a value significantly above the resting potential, so that the current through the shunting conductance is approximately independent of the firing rate. This leads to a subtractive rather than a divisive effect. In addition, at distal synapses, shunting inhibition will also have an approximately subtractive effect if the excitatory conductance is not small compared to the inhibitory conductance. Therefore regulating a cell's passive membrane conductance-for instance, via massive feedback-is not an adequate mechanism for normalizing or scaling its output.


Skull metastasis from carcinoma of the cervix: a rare case and review of the literature.
Skeletal metastasis from carcinoma of the cervix occurs in 0.8-23% of cases. The majority of bone metastases occur either in the long bones or in the vertebrae. Metastasis to distal bones like the skull is rare. Metastasis to bone is commonly associated with advanced stage and poor control of primary disease. We present a rare case of scalp metastasis in a patient with stage IIIB carcinoma of the cervix. The patient had completed radiation therapy treatment resulting in controlled primary disease until she was diagnosed with skull bone metastasis. We present this case because of its rarity and for documentation and discussion.


Tear film lipid layer alterations in allergic conjunctivitis.
To assess the alterations of the tear film lipid layer and tear functions in patients with seasonal allergic conjunctivitis (SAC) and to compare the results with healthy control subjects. Seventy-eight eyes of 39 consecutive patients diagnosed as SAC (mean age 32.6 years; 11 male, 28 female) as well as 20 eyes of 10 healthy control subjects (mean age 32.5 years; 6 male, 4 female) underwent slit-lamp examinations, tear film breakup time measurements (BUT), corneal fluorescein stain scoring, Schirmer test, and tear film lipid layer interferometry. The 2 groups were then compared for the examined parameters. RAST and serum IgE level evaluations were also carried out in the patients to confirm the diagnosis of allergy. The mean BUT was 3.4 +/- 1.5 seconds in patients with SAC compared with the mean value of 12.4 +/- 2.4 seconds in the controls (P < 0.05). There were no significant differences in relation to Schirmer test values between the 2 groups; 78% of the patients with SAC had grade 3 or above dry eye change in tear film lipid layer interferometry, whereas none of the controls had an interferometry grade greater than 3 (grade 1-2 normal; grade 3-4 dry eye; grade 5 severe dry eye). Eyes with SAC had significantly higher tear film lipid layer thickness ranges compared with the control eyes (P < 0.05). SAC was associated with advanced tear instability and thickening of the tear film lipid layer. Evaluation of the tear film lipid layer thickness might be useful in the assessment of the extent of dry eye disease and the treatment outcomes in patients with allergy.


The role of particular strains of Neisseria meningitidis in meningococcal arthritis, pericarditis, and pneumonia.
The clinical presentations of meningococcal diseases other than meningitis or meningococcemia may lead to erroneous diagnosis. Although several reports have described unusual meningococcal diseases, the Neisseria meningitidis strains involved in these forms have been poorly characterized. In this study, meningococcal arthritis and pericarditis were confirmed by isolation of N. meningitidis and/or detection of meningococcal DNA in synovial or pericardial fluid, respectively, and meningococcal pneumonia was detected by isolation of N. meningitidis from blood. From 1999 through 2002, meningococcal disease was bacteriologically confirmed in 26 cases of arthritis, 6 cases of pericarditis, and 33 cases of pneumonia by the National Reference Center for the Meningococci in Paris. We found a statistically significant association between strains of serogroup W135, mostly of the clonal complex ET-37, and arthritis. Pneumonia was most frequently diagnosed in patients aged >70 years, and 54.5% of the strains belonged to serogroup W135, although these strains had heterogeneous phenotypes. Bacteremia is a key step in the pathophysiology of meningococcal disease and precedes any form of invasive infection.


Copper(ii) complexes based on quinoline-derived Schiff-base ligands: synthesis, characterization, HSA/DNA binding ability, and anticancer activity.
Three copper(ii) complexes, [Cu(L1)(NO3)2] (C1), [Cu(L2)Cl2] (C2) and [Cu(L2)SO4]2·H2O (C3), were designed and synthesized by the reaction of Cu(NO3)2·3H2O, CuCl2·2H2O and CuSO4·5H2O with a quinoline-derived Schiff base ligand, L1 or L2, prepared by the condensation of quinoline-8-carbaldehyde with 4-aminobenzoic acid methyl ester or 4-aminobenzoic acid ethyl ester (benzocaine). The efficient bindings of the C1-C3 complexes with human serum albumin (HSA) and calf thymus DNA (CT-DNA) were analyzed by spectroscopy and molecular docking. These complexes could significantly quench the fluorescence of HSA through the static quenching process, and hydrophobic interactions with HSA through the sub-domain IIA and IIIA cavities. The complexes bind to DNA via the intercalative mode and they fit well into the curved contour of the DNA target in the minor groove region. Furthermore, the interaction abilities of the Cu(ii) complexes with HSA/DNA were greater as compared to their corresponding ligands. Interestingly, C1-C3, particularly C3, exhibited more cytotoxicity toward HeLa cells compared to normal HL-7702 cells and three other tumor cell lines (Hep-G2, NCI-H460, and MGC80-3). Their cytotoxicity toward the HeLa cell lines was 1.9-3.5-fold more potent than cisplatin. Further studies indicated that these complexes arrested the cell cycle in the G0/G1 phase and promoted tumor cell apoptosis via a reactive oxygen species (ROS)-mediated mitochondrial pathway.


Nickel silicotungstate-decorated Pt photocathode as an efficient catalyst for triiodide reduction in dye-sensitized solar cells.
A new type of polyoxometalate material, K6SiW11O39Ni(H2O)·xH2O (denoted as SiW11Ni), was successfully synthesized and introduced to a dye-sensitized solar cell (DSSC) with modified traditional Pt as a novel composite counter electrode. The new counter electrode showed superior electrochemical catalytic activity for the reduction of I3- to I- in analysis utilizing a Tafel-polarization curve, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The DSSC assembled with the SiW11Ni/Pt photocathode exhibited an enhanced performance (7.03%) under the standard AM 1.5G illumination compared to the DSSC with a pristine Pt photocathode (6.65%). Furthermore, the DSSC based on the SiW11Ni/Pt photocathode had an increased light-harvesting efficiency and was very stable. The results demonstrate that SiW11Ni/Pt is an alternative and highly efficient counter electrode for dye-sensitized solar cells. Moreover, the facile design strategy is promising for fabricating efficient and inexpensive composite counter electrode catalysts for DSSCs.


Enhance®Fitness Dissemination and Implementation,: 2010-2015: A Scoping Review.
Physical activity has many benefits for older adult physical and mental health. Enhance®Fitness (EF) is an evidence-based group exercise program delivered by community-based organizations. The purpose of this study was to review recent evidence on the dissemination and implementation of EF. A scoping review of qualitative and quantitative studies with EF as main focus was conducted. CINAHL, PubMed, PubMed Central, SCOPUS, Web of Science, PsycINFO, and Google Scholar were searched between October and November 2015 for data-based studies on EF published in 2010-2015. Two team members abstracted each paper independently using a data abstraction tool. Results were summarized using the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework. Seventeen publications met inclusion criteria. EF has reached and is effective across a broad population base, including individuals with low SES and diverse ethnic/racial backgrounds. EF participation may be associated with reduced risk for falls requiring medical care, and is associated with fewer hospital admissions. Analyses of medical cost savings from EF participation and program implementation costs suggest economic benefits of EF implementation for communities. Organization-level maintenance is facilitated by program-specific and organizational factors, such as instructor training and funding. Individual-level maintenance is facilitated by program structure, absence of pain, and increased quality of life. More-rigorous evidence is needed about the association between participation in EF and conditions such as falls. Evaluation of program fidelity, adaptations, and sustainability is limited; more-systematic examination across population groups and types of organizations would help ensure older adults continue to benefit from EF participation.


Difference in susceptibility to gram-negative urinary tract infection between C3H/HeJ and C3H/HeN mice.
The difference in susceptibility to urinary tract infection between C3H/HeJ and C3H/HeN mice was tested for with gram-negative strains differing in lipopolysaccharide composition. Recently, impaired clearance of Escherichia coli from the kidney of C3H/HeJ compared to C3H/HeN mice was shown to be correlated with the LPS low responsiveness. In this study, a difference in clearance from the kidneys of C3H/HeJ and C3H/HeN mice was found only with lipopolysaccharide-containing bacteria. Gram-positive bacteria, e.g., Staphylococcus saprophyticus and Streptococcus agalactiae, were recovered in essentially equal numbers from the kidneys of mice of both strains. In contrast, of the lipopolysaccharide-containing strains used, all persisted in higher numbers in the kidneys of C3H/HeJ mice than in the kidneys of C3H/HeN mice. Variations in the O side chain did not eliminate this difference. E. coli Hu734 O75+K5+ and the rfb- mutant O75-K5+ remained in similar numbers in C3H/HeJ mice, although O75-K5+ was eliminated more rapidly in C3H/HeN mice. The core structure did not affect the differential persistence in the two mouse strains. The rfb mutants with R1-R4 cores were eliminated after 24 h from the C3H/HeN mice, but remained in significant numbers in the kidneys of C3H/HeJ mice. Even the Re mutant of Salmonella minnesota persisted in low numbers in C3H/HeJ mice. The relative bacterial recovery from either mouse strain was related to the overall virulence of the infecting bacterial strain, but the difference between C3H/HeJ and C3H/HeN mice was associated with responsiveness to parts of lipopolysaccharide common to the bacterial strains tested.


Validation of a novel virtual reality robotic simulator.
We evaluated the face, content, and construct validity of what is, to our knowledge, the only available virtual reality simulator based on a complete kinematic representation of the da Vinci surgical system. A total of 5 experts (EPs) and 15 novices (NVs) completed exercises on the Mimic dV-Trainer (MdVT). All participants completed three repetitions of the following tasks: (1) Ring and Cone, (2) String Walk, and (3) Letterboard. Participants rated parameters of face and content validity on a five-point Likert-scale questionnaire. Workload imposed by the simulator was assessed using a NASA Task Load Index questionnaire (TLX). Face validity of the MdVT was established as all 20 participants rated the simulator between average to easy-to-use and above-average to high in all parameters of realism. Participants in both EP and NV groups rated the MdVT's overall relevance to robotic surgery as very high. All five EPs assessed the simulator to be a very good practice format and very useful for training residents, thereby affirming content validity. A preliminary assessment of construct validity suggested that the MdVT could differentiate EPs from NVs. The overall TLX workload scores were lower in the EP group for all parameters except for temporal demand. The MdVT demonstrated excellent face and content validity as well as reasonable workload parameters. The use of this simulator in resident training may help bridge the gap between the safe acquisition of surgical skills and effective performance during live robot-assisted surgery.


Vascular dysfunction and chronic obstructive pulmonary disease: the role of redox balance.
Chronic obstructive pulmonary disease (COPD) is characterized by low pulmonary function, inflammation, free radical production, vascular dysfunction, and subsequently a greater incidence of cardiovascular disease. By administering an acute oral antioxidant cocktail to patients with COPD (n=30) and controls (n=30), we sought to determine the role of redox balance in the vascular dysfunction of these patients. Using a double-blind, randomized, placebo-controlled, crossover design, patients with COPD and controls were ingested placebo or the antioxidant cocktail (vitamin C, vitamin E, α-lipoic acid) after which brachial artery flow-mediated dilation and carotid-radial pulse wave velocity were assessed using ultrasound Doppler. The patients exhibited lower baseline antioxidant levels (vitamin C and superoxide dismutase activity) and higher levels of oxidative stress (thiobarbituic acid reactive species) in comparison with controls. The patients also displayed lower basal flow-mediated dilation (P<0.05), which was significantly improved with antioxidant cocktail (3.1±0.5 versus 4.7±0.6%; P<0.05; placebo versus antioxidant cocktail), but not controls (6.7±0.6 versus 6.9±0.7%; P>0.05; placebo versus antioxidant cocktail). The antioxidant cocktail also improved pulse wave velocity in patients with COPD (14±1 versus 11±1 m·s(-1); P<0.05; placebo versus antioxidant cocktail) while not affecting controls (11±2 versus 10±1 m·s(-1); P>0.05; placebo versus antioxidant). Patients with COPD exhibit vascular dysfunction, likely mediated by an altered redox balance, which can be acutely mitigated by an oral antioxidant. Therefore, free radically mediated vascular dysfunction may be an important mechanism contributing to this population's greater risk and incidence of cardiovascular disease.


Population biology of Gram-positive pathogens: high-risk clones for dissemination of antibiotic resistance.
Infections caused by multiresistant Gram-positive bacteria represent a major health burden in the community as well as in hospitalized patients. Staphylococcus aureus, Enterococcus faecalis and Enterococcus faecium are well-known pathogens of hospitalized patients, frequently linked with resistance against multiple antibiotics, compromising effective therapy. Streptococcus pneumoniae and Streptococcus pyogenes are important pathogens in the community and S. aureus has recently emerged as an important community-acquired pathogen. Population genetic studies reveal that recombination prevails as a driving force of genetic diversity in E. faecium, E. faecalis, S. pneumoniae and S. pyogenes, and thus, these species are weakly clonal. Although recombination has a relatively modest role driving the genetic variation of the core genome of S. aureus, the horizontal acquisition of resistance and virulence genes plays a key role in the emergence of new clinically relevant clones in this species. In this review, we discuss the population genetics of E. faecium, E. faecalis, S. pneumoniae, S. pyogenes and S. aureus. Knowledge of the population structure of these pathogens is not only highly relevant for (molecular) epidemiological research but also for identifying the genetic variation that underlies changes in clinical behaviour, to improve our understanding of the pathogenic behaviour of particular clones and to identify novel targets for vaccines or immunotherapy.


A novel MEN1 intronic mutation associated with multiple endocrine neoplasia type 1.
To investigate a family with an unusual combination of multiple endocrine neoplasia (MEN1) and the McCune-Albright syndrome for MEN1 mutations and activating GNAS1 mutations at codons Arg201 and Gln227. DNA sequences analyses were performed of the MEN1 gene and codons Arg201 and Gln227 of the GNAS1 gene, using leucocyte and endocrine tissue DNA. A c-->g transversion at position -9 bp in intron 9 of the MEN1 gene was identified. This resulted in the generation of a BmrI restriction endonuclease site, and its presence and segregation with MEN1 in the family was demonstrated by restriction endonuclease analysis. The c-->g transversion was shown to result in the generation of a novel acceptor splice site (ccag) using reverse transcriptase-polymerase chain reaction (RT-PCR) and ribonucleic acid (RNA) obtained from Epstein-Barr virus (EBV)-transformed lymphoblasts. Utilization of this splice site resulted in an abnormal messenger RNA (mRNA) transcript that contained an additional eight bases. This predicted a frameshift that would result in nine missense amino acids followed by a premature termination signal. GNAS1 mutations were not detected in the patient with McCune-Albright syndrome. The occurrence of MEN1 and the McCune-Albright syndrome in this family are coincidental findings and not due to a common genetic aetiology. However, our results have identified a novel MEN1 mutation that occurs in intron 9 and generates a novel acceptor splice site. Such splicing-affecting genomic variants (SpaGVs) are increasingly being recognized as a cause of human disease, and are likely to be of significance in the 10% of MEN1 patients who do not have coding region mutations.


Identification of a fourth gene involved in dTDP-rhamnose synthesis in Streptococcus mutans.
We had isolated three genes (rmlA, rmlB, and rmlC) involved in dTDP-rhamnose synthesis in Streptococcus mutans and found that three genes were insufficient for dTDP-rhamnose synthesis (Y. Tsukioka, Y. Yamashita, T. Oho, Y. Nakano, and T. Koga, J. Bacteriol. 179:1126-1134, 1997). The rmlD gene of S. mutans, encoding the enzyme which catalyzes the last step of dTDP-rhamnose synthesis, has been cloned and sequenced. The cell extract of Escherichia coli expressing the rmlD gene of S. mutans exhibited enzymatic activity corresponding to its counterpart in Shigella flexneri, a gram-negative bacterium. Rhamnose was not detected in the cell wall preparation purified from the mutant in which the cloned gene was insertionally inactivated. Rabbit antiserum against S. mutans serotype c-specific antigen did not react with autoclaved extracts from the mutant. The rmlD gene product of S. mutans compensated for the incompleteness of dTDP-rhamnose synthesis by the three previously isolated genes. These results indicate that the rmlD gene product is indispensable for the dTDP-rhamnose pathway and subsequently for the synthesis of serotype-specific antigen in S. mutans. Furthermore, conservation of the rmlD gene in Streptococcus species was demonstrated by Southern blot analysis.


Feasibility and Reliability of Rapid Diagnosis of Myocardial Infarction.
Prevailing hospital practice dictates a protracted phase of observation for patients with chest pain to establish or exclude the diagnosis of myocardial infarction. Early diagnosis of acute myocardial infarction may improve patient care and reduce both complications and hospital costs. A study was performed to investigate the feasibility of early diagnosis of myocardial infarction within the first 9 hours of the hospital stay. The records of all patients admitted with chest pain within one calendar year were analyzed. The timing of creatine kinase-MB (CK-MB) quantification was determined with reference to the initial phlebotomy (time 0). An enzymatic diagnosis of myocardial infarction was assigned if any determination of CK-MB exceeded the upper limit of normal, and the diagnosis of each patient at or before 9 hours (early diagnosis) was compared to the ultimate diagnosis at 14 to 24 hours (final diagnosis) beyond initial assessment. Of the 528 included patients, 523 patients (99.1%) had identical early and final diagnostic outcomes; 5 patients (0.9%) had conflicting results. An early diagnosis of myocardial infarction was assigned to 195 of the 528 patients (36.9%). Of these, 190 achieved the diagnosis within 9 hours (sensitivity 97.4%). The negative predictive value was 98.5%. Standard CK-MB mass measurements within 9 hours of arrival provided an accurate clinical assessment in > 99% of the cases. The high sensitivity and negative predictive values suggest that early diagnosis of myocardial infarction is feasible and reliable.


Genomic assessment of quarantine measures to prevent SARS-CoV-2 importation and transmission.
Mitigation of SARS-CoV-2 transmission from international travel is a priority. We evaluated the effectiveness of travellers being required to quarantine for 14-days on return to England in Summer 2020. We identified 4,207 travel-related SARS-CoV-2 cases and their contacts, and identified 827 associated SARS-CoV-2 genomes. Overall, quarantine was associated with a lower rate of contacts, and the impact of quarantine was greatest in the 16-20 age-group. 186 SARS-CoV-2 genomes were sufficiently unique to identify travel-related clusters. Fewer genomically-linked cases were observed for index cases who returned from countries with quarantine requirement compared to countries with no quarantine requirement. This difference was explained by fewer importation events per identified genome for these cases, as opposed to fewer onward contacts per case. Overall, our study demonstrates that a 14-day quarantine period reduces, but does not completely eliminate, the onward transmission of imported cases, mainly by dissuading travel to countries with a quarantine requirement.


Kras(G12D) and Nkx2-1 haploinsufficiency induce mucinous adenocarcinoma of the lung.
Mucinous adenocarcinoma of the lung is a subtype of highly invasive pulmonary tumors and is associated with decreased or absent expression of the transcription factor NK2 homeobox 1 (NKX2-1; also known as TTF-1). Here, we show that haploinsufficiency of Nkx2-1 in combination with oncogenic Kras(G12D), but not with oncogenic EGFR(L858R), caused pulmonary tumors in transgenic mice that were phenotypically similar to human mucinous adenocarcinomas. Gene expression patterns distinguished tumor goblet (mucous) cells from nontumorigenic airway and intestinal goblet cells. Expression of NKX2-1 inhibited urethane and oncogenic Kras(G12D)-induced tumorigenesis in vivo. Haploinsufficiency of Nkx2-1 enhanced Kras(G12D)-mediated tumor progression, but reduced EGFR(L858R)-mediated progression. Genome-wide analysis of gene expression demonstrated that a set of genes induced in mucinous tumors was shared with genes induced in a nontumorigenic chronic lung disease, while a distinct subset of genes was specific to mucinous tumors. ChIP with massively parallel DNA sequencing identified a direct association of NKX2-1 with the genes induced in mucinous tumors. NKX2-1 associated with the AP-1 binding element as well as the canonical NKX2-1 binding element. NKX2-1 inhibited both AP-1 activity and tumor colony formation in vitro. These data demonstrate that NKX2-1 functions in a context-dependent manner in lung tumorigenesis and inhibits Kras(G12D)-driven mucinous pulmonary adenocarcinoma.


Internet-based surveillance of Influenza-like-illness in the UK during the 2009 H1N1 influenza pandemic.
Internet-based surveillance systems to monitor influenza-like illness (ILI) have advantages over traditional (physician-based) reporting systems, as they can potentially monitor a wider range of cases (i.e. including those that do not seek care). However, the requirement for participants to have internet access and to actively participate calls into question the representativeness of the data. Such systems have been in place in a number of European countries over the last few years, and in July 2009 this was extended to the UK. Here we present results of this survey with the aim of assessing the reliability of the data, and to evaluate methods to correct for possible biases. Internet-based monitoring of ILI was launched near the peak of the first wave of the UK H1N1v influenza pandemic. We compared the recorded ILI incidence with physician-recorded incidence and an estimate of the true number of cases over the course of the epidemic. We also compared overall attack rates. The effect of using different ILI definitions and alternative denominator assumptions on incidence estimates was explored. The crude incidence measured by the internet-based system appears to be influenced by individuals who participated only once in the survey and who appeared more likely to be ill. This distorted the overall incidence trend. Concentrating on individuals who reported more than once results in a time series of ILI incidence that matches the trend of case estimates reasonably closely, with a correlation of 0.713 (P-value: 0.0001, 95% CI: 0.435, 0.867). Indeed, the internet-based system appears to give a better estimate of the relative height of the two waves of the UK pandemic than the physician-recorded incidence. The overall attack rate is, however, higher than other estimates, at about 16% when compared with a model-based estimate of 6%. Internet-based monitoring of ILI can capture the trends in case numbers if appropriate weighting is used to correct for differential response. The overall level of incidence is, however, difficult to measure. Internet-based systems may be a useful adjunct to existing ILI surveillance systems as they capture cases that do not necessarily contact health care. However, further research is required before they can be used to accurately assess the absolute level of incidence in the community.


Differences in neuropsychological performance between subtypes of obsessive-compulsive disorder.
Neuropsychological studies have suggested that frontal-striatal dysfunction plays a role in obsessive-compulsive disorder (OCD), although findings have been inconsistent, possibly due to heterogeneity within the disorder and methodological issues. The purpose of the present study was therefore to compare the neuropsychological performance of different subtypes of OCD and matched non-clinical controls (NCs) on the Cambridge Automated Neuropsychological Test Battery (CANTAB). Fifty-nine OCD patients and 59 non-clinical controls completed selected tests from CANTAB examining executive function, visual memory and attentional-set shifting. Depression, anxiety and OCD symptoms were also assessed. From 59 OCD patients, four subtypes were identified: (i) washers; (ii) checkers; (iii) obsessionals; and (iv) mixed symptom profile. Comparisons between washers, checkers, obsessionals and NCs indicated few differences, although checkers were generally found to exhibit poorer performance on spatial working memory, while obsessionals performed poorly on the spatial recognition task. Both checkers and the mixed subgroups showed slowed initial movement on the Stockings of Cambridge planning task and poorer pattern recognition relative to NCs. Overall the results suggested greater impairments in performance on neuropsychological tasks in checkers relative to other subtypes, although the observed effects were small and the conclusions limited by the small subtype samples. Future research will need to account for factors that influence neuropsychological performance in OCD subtypes.


Evidence-based ventilator weaning and discontinuation.
Ventilator management of a patient who is recovering from acute respiratory failure must balance competing objectives. Discontinuing mechanical ventilation and removing the artificial airway as soon as possible reduces the risk of ventilator-induced lung injury, nosocomial pneumonia, airway trauma from the endotracheal tube, and unnecessary sedation, but premature ventilator-discontinuation or extubation can cause ventilatory muscle fatigue, gas exchange failure, and loss of airway protection. In 1999 the McMaster University Outcomes Research Unit conducted a comprehensive evidence-based review of the literature on ventilator-discontinuation. Using that literature review, the American College of Chest Physicians, the Society of Critical Care Medicine, and the American Association for Respiratory Care created evidence-based guidelines, which include the following principles: 1. Frequent assessment is required to determine whether ventilatory support and the artificial airway are still needed. 2. Patients who continue to require support should be continually re-evaluated to assure that all factors contributing to ventilator dependence are addressed. 3. With patients who continue to require support, the support strategy should maximize patient comfort and provide muscle unloading. 4. Patients who require prolonged ventilatory support beyond the intensive care unit should go to specialized facilities that can provide more gradual support reduction strategies. 5. Ventilator-discontinuation and weaning protocols can be effectively carried out by nonphysician clinicians.


Quality of care in the US territories.
Health care quality in the US territories is poorly characterized. We used process measures to compare the performance of hospitals in the US territories and in the US states. Our sample included nonfederal hospitals located in the United States and its territories discharging Medicare fee-for-service (FFS) patients with a principal discharge diagnosis of acute myocardial infarction (AMI), heart failure (HF), or pneumonia (PNE) (July 2005-June 2008). We compared risk-standardized 30-day mortality and readmission rates between territorial and stateside hospitals, adjusting for performance on core process measures and hospital characteristics. In 57 territorial hospitals and 4799 stateside hospitals, hospital mean 30-day risk-standardized mortality rates were significantly higher in the US territories (P<.001) for AMI (18.8% vs 16.0%), HF (12.3% vs 10.8%), and PNE (14.9% vs 11.4%). Hospital mean 30-day risk-standardized readmission rates (RSRRs) were also significantly higher in the US territories for AMI (20.6% vs 19.8%; P=.04), and PNE (19.4% vs 18.4%; P=.01) but was not significant for HF (25.5% vs 24.5%; P=.07). The higher risk-standardized mortality rates in the US territories remained statistically significant after adjusting for hospital characteristics and core process measure performance. Hospitals in the US territories had lower performance on all core process measures (P<.05). Compared with hospitals in the US states, hospitals in the US territories have significantly higher 30-day mortality rates and lower performance on every core process measure for patients discharged after AMI, HF, and PNE. Eliminating the substantial quality gap in the US territories should be a national priority.


Flexible photonic crystal waveguide branches with arbitrary branching angles.
A fundamental Y branch based on a flexible photonic crystal waveguide is presented. By combining this fundamental Y branch with flexible waveguides, flexible waveguide branches with arbitrary branching angles are constructed. Numerical simulations of these branches indicate that without any structural optimization, near-complete transmission is observed within a wide frequency band. Owing to their unique flexibility, these waveguide branches are expected to be applied to high-density photonic integrated circuits after further research.


Computational analysis of site differences in selective aliphatic C-H hydroxylation by nonheme iron-oxo complexes.
Selective C-H hydroxylation by nonheme iron complexes offers a promising method in the field of organic synthesis. Aliphatic C-H bond oxidation reactions of pivalate (R) catalyzed by [Fe(S,S-PDP)(CH3CN)2]2+ (CAT1) were examined using the density functional theory. Our calculations of the CH3CN solvent agree with the experimental findings. However, it was observed that the gas-phase results did not replicate selective C-H hydroxylation observed experimentally when CAT1 catalyzed hydrocarbon oxidations by H2O2via an HO-FeV[double bond, length as m-dash]O oxidant (CAT1a). We inferred that the difference was mainly from hydrogen bonding formation, (CAT1a) O-HO[double bond, length as m-dash]C (R), in certain gaseous H-abstraction transition states (TSH). Then, the appearance of the stronger (CAT1a) O-HN[triple bond, length as m-dash]CCH3-solvent weakened the aforementioned interaction, leading to C-H activation influenced primarily by their electronic and steric properties. Such a deduction explained the same selective C-H found in both phases of reactions with CAT1b, a cyclic ferric peracetate oxidant, by the reason of TSH without the influence of H-bonding. Another interesting finding was that the commonly recognized radical intermediate was further isomerized by a favorable electron rearrangement. Thus, the subsequent OH-rebound behavior proceeded by an electrostatic interaction. This study provides mechanistic clues for modifying regioselective C-H hydroxylation for molecule synthesis applications.


A water-mediated and substrate-assisted aminoacylation mechanism in the discriminating aminoacyl-tRNA synthetase GlnRS and non-discriminating GluRS.
Glutaminyl-tRNA synthetase (GlnRS) catalyzes the aminoacylation of glutamine to the corresponding tRNAGln. However, most bacteria and all archaea lack GlnRS and thus an indirect noncanonical aminoacylation is required. With the assistance of a non-discriminating version of Glutamyl-tRNA synthetases (ND-GluRS) the tRNAGln is misaminoacylated by glutamate. In this study, we have computationally investigated the aminoacylation mechanism in GlnRS and ND-GluRS employing Molecular Dynamics (MD) simulations, Quantum Mechanics (QM) cluster and Quantum Mechanics/Molecular Mechanics (QM/MM) calculations. Our investigations demonstrated the feasibility of a water-mediated, substrate-assisted catalysis pathway with rate limiting steps occurring at energy barriers of 25.0 and 25.4 kcal mol-1 for GlnRS and ND-GluRS, respectively. A conserved lysine residue participates in a second proton transfer to facilitate the departure of the adenosine monophosphate (AMP) group. Thermodynamically stable (-29.9 and -9.3 kcal mol-1 for GlnRS and ND-GluRS) product complexes are obtained only when the AMP group is neutral.


Reconstructing the in vivo dynamics of hematopoietic stem cells from telomere length distributions.
We investigate the in vivo patterns of stem cell divisions in the human hematopoietic system throughout life. In particular, we analyze the shape of telomere length distributions underlying stem cell behavior within individuals. Our mathematical model shows that these distributions contain a fingerprint of the progressive telomere loss and the fraction of symmetric cell proliferations. Our predictions are tested against measured telomere length distributions in humans across all ages, collected from lymphocyte and granulocyte sorted telomere length data of 356 healthy individuals, including 47 cord blood and 28 bone marrow samples. We find an increasing stem cell pool during childhood and adolescence and an approximately maintained stem cell population in adults. Furthermore, our method is able to detect individual differences from a single tissue sample, i.e. a single snapshot. Prospectively, this allows us to compare cell proliferation between individuals and identify abnormal stem cell dynamics, which affects the risk of stem cell related diseases.


Prevention and control of bacterial infections associated with medical devices.
Bacteria that grow in association with medical devices always form slime enclosed biofilms, within which they are protected, to a large extent, from the bactericidal activity of chemical biocides and antibiotics. Mature biofilms (> 7 days) are demonstrably resistant to 500-5,000 times the concentrations of these agents than are necessary to kill free floating (planktonic) cells of the same organism. The authors have discovered that this well established inherent resistance of biofilm bacteria to antibacterial agents can be completely obviated if these agents are applied to these adherent populations within an electric field. The killing of biofilm bacteria by antibiotics can be dramatically enhanced by relatively weak electric fields (1.5 V/cm and 15 microA/cm2) that, in themselves, have no deleterious effects on these slime protected populations adherent to plastic or metal surfaces. This bioelectric technology can readily be used to enhance the preimplantation sterilization of medical devices by biocides. The authors suggest that it may also be used to control biofilm formation and consequent infection by electrically enhanced perioperative antibiotic prophylaxis and by electrically enhanced penetration of antibiotics to kill the biofilm bacteria that form the inherently resistant nidus of chronic device related infections.


The emissivity of the diffuse spherical cavity.
Similarities between various cavity emissivity theories have been examined. It is shown here that, for the special case of the (isothermal) diffuse spherical cavity, the closed form emissivity expressions obtainable from the work of Gouffé, DeVos, and Sparrow and Jonsson agree exactly. Further, this result is not limited by the size of the opening in the cavity.


CuH-Catalyzed Enantioselective Ketone Allylation with 1,3-Dienes: Scope, Mechanism, and Applications.
Chiral tertiary alcohols are important building blocks for the synthesis of pharmaceutical agents and biologically active natural products. The addition of carbon nucleophiles to ketones is the most common approach to tertiary alcohol synthesis but traditionally relies on stoichiometric organometallic reagents that are difficult to prepare, sensitive, and uneconomical. We describe a mild and efficient method for the copper-catalyzed allylation of ketones using widely available 1,3-dienes as allylmetal surrogates. Homoallylic alcohols bearing a wide range of functional groups are obtained in high yield and with good regio-, diastereo-, and enantioselectivity. Mechanistic investigations using density functional theory (DFT) implicate the in situ formation of a rapidly equilibrating mixture of isomeric copper(I) allyl complexes, from which Curtin-Hammett kinetics determine the major isomer of the product. A stereochemical model is provided to explain the high diastereo- and enantioselectivity of this process. Finally, this method was applied to the preparation of an important drug, ( R)-procyclidine, and a key intermediate in the synthesis of several pharmaceuticals.


Human cytomegalovirus UL69 protein is required for efficient accumulation of infected cells in the G1 phase of the cell cycle.
Human cytomegalovirus blocks cell-cycle progression in the G(1) compartment upon infection of primary human fibroblasts. The virus-coded UL69 protein can institute a G(1) block when expressed in cells in the absence of virus infection. We have constructed a cytomegalovirus mutant, TNsubUL69, that lacks the UL69 coding region. This virus grows slowly in fibroblasts, but produces a wild-type yield after an extended delay. It grows with normal kinetics in cells coinfected with a recombinant retrovirus, retroUL69, which expresses UL69 protein, demonstrating that its growth defect results from the mutation in the UL69 gene. UL69 protein is packaged within virus particles, and it was possible for us to produce two types of virus stocks. TNsubUL69(+pUL69) lacks the UL69 gene but contains UL69 protein in virus particles. It is produced by growth in fibroblasts that are coinfected with retroUL69. TNsubUL69(-pUL69) lacks the UL69 gene and protein. It is produced by growth in fibroblasts that do not contain UL69 protein. The mutant virions lacking both the UL69 gene and protein fail to induce a cell-cycle block with normal efficiency, whereas the mutant particles lacking the gene but containing the protein can institute the block. These results are consistent with the view that the UL69 protein contributes to the cytomegalovirus-induced cell-cycle block, and they suggest that UL69 protein delivered to cells within virions can induce the block without the synthesis of additional UL69 protein encoded by the infecting viral genome.


Acute salivary hormone responses to complex exercise bouts.
The combination of resistance and plyometric training, or complex training, may yield greater functional gains than either method alone. As steroid hormones respond to exercise stimuli and modulate the functional outcomes, it is possible that complex training creates an enhanced anabolic physiological milieu for adaptation. We investigated acute responses of salivary testosterone and cortisol to complex exercise bouts. After a standardized warm-up, 16 semiprofessional rugby players performed 1 of 4 exercise bouts in a cross-over manner: power-power; power-strength; strength-power; or strength-strength. Each player completed each of the 4 bouts twice over a 4-week period in a balanced random order such that each player performed a total of 8 bouts. The power block consisted of 3 sets of 3 repetitions of jump squat exercise at 50% of 1-repetition maximum load. The strength block consisted of three sets of three repetitions of box squat exercise at a 3-repetition maximum load. There were 3-minute rest periods between sets and 4-minute rest periods between exercise blocks. Saliva was sampled before, during, and immediately after the exercise bout. The greatest overall hormonal responses were a small increase in testosterone (13%; 90% confidence limits ± 7%) and a trivial increase in cortisol (27%; ± 30%) after the strength-power bout. A clear difference was observed between the strength-power and the power-power bouts immediately after exercise for testosterone (10%; ± 8%) and cortisol (29%; ± 17%). The preceding exercise block had little effect on subsequent strength and power performance. The hormonal response after the strength-power bout suggests that this exercise sequence provides an enhanced anabolic milieu for adaptation.


Predicting success in weaning from mechanical ventilation.
We identified 65 observational studies of weaning predictors that had been reported in 70 publications. After grouping predictors with similar names but different thresholds, the following predictors met our relevance criteria: heterogeneous populations, 51; COPD patients, 21; and cardiovascular ICU patients, 45. Many variables were of no use in predicting the results of weaning. Moreover, few variables had been studied in > 50 patients or had results presented to generate estimates of predictive power. For stepwise reductions in mechanical support, the most promising predictors were a rapid shallow breathing index (RSBI) < 65 breaths/min/L (measured using the ventilator settings that were in effect at the time that the prediction was made) and a pressure time product < 275 cm H2O/L/s. The pooled likelihood ratios (LRs) were 1.1 (95% confidence interval [CI], 0.95 to 1.28) for a respiratory rate [RR] of < 38 breaths/min and 0.32 (95% CI, 0.06 to 1.71) for an RR of > 38 breaths/min, which indicate that an RR of < 38 breaths/min leaves the probability of successful weaning virtually unchanged but that a value of > 38 breaths/min leads to a small reduction in the probability of success in weaning the level of mechanical support. For trials of unassisted breathing, the most promising weaning predictors include the following: RR; RSBI; a product of RSBI and occlusion pressure < 450 cm H2O breaths/min/L; maximal inspiratory pressure (PImax) < 20 cm H2O; and a knowledge-based system for adjusting pressure support. Pooled results for the power of a positive test result for both RR and RSBI were limited (highest LR, 2.23), while the power of a negative test result was substantial (ie, LR, 0.09 to 0.23). Summary data suggest a similar predictive power for RR and RSBI. In the prediction of successful extubation, an RR of < 38 breaths/min (sensitivity, 88%; specificity, 47%), an RSBI < 100 or 105 breaths/min/L (sensitivity, 65 to 96%; specificity, 0 to 73%), PImax, and APACHE (acute physiology and chronic health evaluation) II scores that are obtained at hospital admission appear to be the most promising. After pooling, two variables appeared to have some value. An RR of > 38 breaths/min and an RSBI of > 100 breaths/min/L appear to reduce the probability of successful extubation, and PImax < 0.3, for which the pooled LR is 2.23 (95% CI, 1.15 to 4.34), appears to marginally increase the likelihood of successful extubation. Judging by areas under the receiver operator curve for all variables, none of these variables demonstrate more than modest accuracy in predicting weaning outcome. Why do most of these tests perform so poorly? The likely explanation is that clinicians have already considered the results when they choose patients for trials of weaning.


The Role and Mechanism of Erythrocyte Invasion by Francisella tularensis.
Francisella tularensis is an extremely virulent bacterium that can be transmitted naturally by blood sucking arthropods. During mammalian infection, F. tularensis infects numerous types of host cells, including erythrocytes. As erythrocytes do not undergo phagocytosis or endocytosis, it remains unknown how F. tularensis invades these cells. Furthermore, the consequence of inhabiting the intracellular space of red blood cells (RBCs) has not been determined. Here, we provide evidence indicating that residing within an erythrocyte enhances the ability of F. tularensis to colonize ticks following a blood meal. Erythrocyte residence protected F. tularensis from a low pH environment similar to that of gut cells of a feeding tick. Mechanistic studies revealed that the F. tularensis type VI secretion system (T6SS) was required for erythrocyte invasion as mutation of mglA (a transcriptional regulator of T6SS genes), dotU, or iglC (two genes encoding T6SS machinery) severely diminished bacterial entry into RBCs. Invasion was also inhibited upon treatment of erythrocytes with venom from the Blue-bellied black snake (Pseudechis guttatus), which aggregates spectrin in the cytoskeleton, but not inhibitors of actin polymerization and depolymerization. These data suggest that erythrocyte invasion by F. tularensis is dependent on spectrin utilization which is likely mediated by effectors delivered through the T6SS. Our results begin to elucidate the mechanism of a unique biological process facilitated by F. tularensis to invade erythrocytes, allowing for enhanced colonization of ticks.


Impaired local intrinsic immunity to SARS-CoV-2 infection in severe COVID-19.
SARS-CoV-2 infection can cause severe respiratory COVID-19. However, many individuals present with isolated upper respiratory symptoms, suggesting potential to constrain viral pathology to the nasopharynx. Which cells SARS-CoV-2 primarily targets and how infection influences the respiratory epithelium remains incompletely understood. We performed scRNA-seq on nasopharyngeal swabs from 58 healthy and COVID-19 participants. During COVID-19, we observe expansion of secretory, loss of ciliated, and epithelial cell repopulation via deuterosomal cell expansion. In mild and moderate COVID-19, epithelial cells express anti-viral/interferon-responsive genes, while cells in severe COVID-19 have muted anti-viral responses despite equivalent viral loads. SARS-CoV-2 RNA+ host-target cells are highly heterogenous, including developing ciliated, interferon-responsive ciliated, AZGP1high goblet, and KRT13+ "hillock"-like cells, and we identify genes associated with susceptibility, resistance, or infection response. Our study defines protective and detrimental responses to SARS-CoV-2, the direct viral targets of infection, and suggests that failed nasal epithelial anti-viral immunity may underlie and precede severe COVID-19.


Depression after traumatic brain injury: a National Institute on Disability and Rehabilitation Research Model Systems multicenter investigation.
To identify the frequency and manifestations of depression after traumatic brain injury (TBI) and the factors that contribute to developing this mood disorder. A prospective, nationwide, multicenter study; 17 centers supplied data from medical records and patient responses on a standardized criterion instrument. Traumatic Brain Injury Model Systems programs. A demographically diverse sample of 666 outpatients with TBI was evaluated 10 to 126 months after injury. Not applicable. Depressive symptoms were characterized with the Neurobehavioral Functioning Inventory by using the Diagnostic and Statistical Manual of Mental Disorders (4th ed; DSM-IV) diagnostic framework. Analysis of variance and Pearson correlations were used to identify factors that were significantly related to depression. Fatigue (29%), distractibility (28%), anger or irritability (28%), and rumination (25%) were the most commonly cited depressive symptoms in the sample. Twenty-seven percent of patients with TBI met the prerequisite number (>/=5) of criterion A symptoms for a DSM-IV diagnosis of major depressive disorder. Feeling hopeless, feeling worthless, and difficulty enjoying activities were the 3 symptoms that most differentiated depressed from nondepressed patients. Patients who were unemployed at the time of injury and who were impoverished were significantly more likely to report DSM-IV criterion A symptoms than patients who were employed, were students, or were retired due to age. Time after injury, injury severity, and postinjury marital status were not significantly related to depression. Patients with TBI are at great risk for developing depressive symptoms. Findings provide empirical support for the inclusion of depression evaluation and treatment protocols in brain injury programs. Unemployment and poverty may be substantial risk factors for the development of depressive symptoms. Future research should develop biopsychosocial predictive models to identify high-risk patients and examine the efficacy of treatment interventions.


Homeostatic maintenance of ponderosa pine gas exchange in response to stand density changes.
Homeostatic maintenance of gas exchange optimizes carbon gain per water loss. Homeostasis is regulated by short-term physiological and long-term structural mechanisms, both of which may respond to changes in resource availability associated with competition. Therefore, stand density regulation via silvicultural manipulations may facilitate growth and survival through mechanisms operating at both short and long timescales. We investigated the responses of ponderosa pine (Pinus ponderosa) to stand basal area manipulations in Arizona, USA. Stand basal area was manipulated to seven replicated levels in 1962 and was maintained for four decades by decadal thinning. We measured basal area increment (BAI) to assess the response and sustainability of wood growth, carbon isotope discrimination (A) inferred from annual rings to assess the response of crown gas exchange, and ratios of leaf area to sapwood area (A(l):A(s)) to assess longer term structural acclimation. Basal area treatments increased soil water potential (r2 = 0.99) but did not affect photosynthetic capacity. BAI increased within two years of thinning, and the 40-year mean BAI was negatively correlated with stand basal area (r2 = 0.98). delta was negatively correlated with stand basal area for years 5 through 12 after thinning (r2 = 0.90). However, delta was relatively invariant with basal area for the period 13-40 years after initial thinning despite maintenance of treatment basal areas via repeated decadal thinnings. Independent gas exchange measurements verified that the ratio of photosynthesis to stomatal conductance was invariant with basal area, but absolute values of both were elevated at lower basal areas. A(l):A(s) was negatively correlated with basal area (r2 = 0.93). We hypothesize that increased A(l):A(s) is a homeostatic response to increased water availability that maximizes water-use efficiency and whole-tree carbon uptake. Elevated A(l):A(s) of trees at low basal areas was associated with greater resilience to climate, i.e., greater absolute BAI during drought; however, trees with high A(l):A(s) in low basal area stands also exhibited the greatest sensitivity to drought, i.e., greater relative decline in BAI.


Inpatient psychosocial rehabilitation in rural NSW: assessment of clinically significant change for people with severe mental illness.
The aim of the present study was to describe an inpatient psychosocial rehabilitation programme in rural New South Wales and to assess the effectiveness of the programme using measures of clinically significant change. The first 88 patients with a schizophrenia spectrum disorder to enter the Manara Clinic and Turon House, New South Wales, psychosocial rehabilitation programmes were assessed at admission and discharge using the Brief Psychiatric Rating Scale, the Health of the Nation Outcome Scales, and the Kessler-10 self-report measure. Significant improvements in psychiatric symptomatology, psychosocial functioning, and psychological distress were found over the course of the inpatient stay. Clinical significance analyses using patients in the community as the reference group indicated a reliable and clinically significant improvement for 33% of inpatients on psychiatric symptomatology, 39% of inpatients on psychosocial functioning, and 21% of inpatients on psychological distress. The psychosocial rehabilitation programme provides clinically significant initial benefits for patients with severe mental illnesses. More attention needs to be paid to evaluating which components of psychosocial rehabilitation contribute most to these benefits. Follow-up evaluation is required to determine whether the benefits of this programme are sustained in the community.