Sodium, ATP, and intracellular pH transients during reversible complete ischemia of dog cerebrum.
We tested the hypotheses that with the onset of cerebral ischemia, massive cellular sodium influx does not occur until adenosine triphosphate is fully depleted and that on reperfusion, neuronal sodium efflux does not occur until adenosine triphosphate is fully restored. We examined the temporal relationships among transcellular sodium, energy metabolism, and intracellular pH with sodium and phosphorus magnetic resonance spectroscopy in a new, hemodynamically stable, brain stem-sparing model of reversible, complete cerebral ischemia in eight anesthetized dogs. Inflation of a neck tourniquet after placement of glue at the tip of the basilar artery resulted in decreased blood flow to the cerebrum from 29 +/- 5 to 0.3 +/- 0.5 ml/min/100 g. Medullary blood flow was not significantly affected, and arterial blood pressure was unchanged. Sodium signal intensity decreased and did not lag behind the fall in adenosine triphosphate. After 12 minutes of ischemia, reperfusion resulted in a more rapid recovery of sodium intensity (12.4 +/- 4.8 minutes) than either adenosine triphosphate (16.5 +/- 3.7 minutes) or intracellular pH (38.9 +/- 1.8 minutes). Because intracellular sodium has a weaker signal than extracellular sodium, the decreased sodium intensity is interpreted as sodium influx and indicates that sodium influx does not require full depletion of adenosine triphosphate. Rapid recovery of sodium intensity during early reperfusion may represent sodium efflux, although increased plasma volume and sodium uptake from plasma may also contribute. If our interpretation of the sodium signal is correct, delayed recovery of adenosine triphosphate may be due to the utilization of adenosine triphosphate for the restoration of transcellular sodium gradient.


Crossing the pain barrier: P2 receptors as targets for novel analgesics.
In 1995 the P2X3 receptor was found to be expressed at high levels in nociceptive sensory neurones, consistent with earlier reports that ATP induced pain in humans and animals. At first it was thought that ATP was most likely to play a role in acute pain, following its release from damaged or stressed cells and since then a wide variety of experimental techniques and approaches have been used to study this possibility. Whilst it is clear that exogenous and endogenous ATP can indeed acutely stimulate sensory neurones, more recent reports using gene knockout and antisense oligonucleotide technologies, and a novel, selective P2X3 antagonist, A-317491, all indicate that ATP and P2X3 receptors are more likely to be involved in chronic pain conditions, particularly chronic inflammatory and neuropathic pain. These reports indicate that P2X3 receptors on sensory nerves may be tonically activated by ATP released from nearby damaged or stressed cells, or perhaps from the sensory nerves themselves. This signal, when transmitted to the CNS, will be perceived consciously as chronic pain. In addition, it is now clear that several subtypes of P2Y receptor are also expressed in sensory neurones. Although their distribution and functions have not been as widely studied as P2X receptors, the effects that they mediate indicate that they might also be considered as therapeutic targets in the treatment of pain. Although our ability to treat persistent painful conditions, such as chronic inflammatory and neuropathic pain, has improved in recent years, these conditions are often resistant to currently available therapies, such as opioids or non-steroidal anti-inflammatory drugs. This reflects a limited understanding of the underlying pathophysiology. It is now clear that the development and maintenance of chronic pain are mediated by multiple factors, but many of these factors, and the receptors and mechanisms through which they act, remain to be identified. Chronic pain is debilitating and can greatly decrease quality of life, not just due to the pain per se, but also because of the depression that can often ensue. Thus a greater understanding of the mechanisms that underlie chronic pain will help identify new targets for novel analgesics, which will be of great therapeutic benefit to many people.


Does the racial composition of the school environment influence children's body mass index?
This study investigates the degree to which the racial composition of the school environment may influence the body mass index (BMI) of children aged 10 to 18 years. This research may be viewed as extending prior work that has found that the prevalence of risk behaviors among nonwhite adolescents is influenced by exposure to white adolescents. This research used data from the Survey of Adults and Youth, which was conducted as part of the evaluation of the Robert Wood Johnson Foundation's Urban Health Initiative. The study population for this analysis is comprised of parent and child respondents in the 2004 to 2005 survey wave who lived in one of the five program cities: Baltimore, Detroit, Oakland, Philadelphia, and Richmond. We constructed two-level school random effects models and added school and census tract-level variables that describe the racial composition of the residential community and the school attended. Black and Hispanic adolescent girls who attend schools with a mostly nonwhite student body have higher BMIs than do their white counterparts. However, black girls in predominately white schools do not have higher BMIs than white girls. Further, black and Hispanic girls whose schoolmates are predominately white have significantly lower BMIs than black and Hispanic girls in schools where fewer than half the students are white. These associations are not found among boys, and are net of a broad variety of individual, household, and group level characteristics. Our findings suggest that the BMI of minority adolescent girls is influenced by the norms of the social environment.


Multiple conserved cell adhesion protein interactions mediate neural wiring of a sensory circuit in C. elegans.
Nervous system function relies on precise synaptic connections. A number of widely-conserved cell adhesion proteins are implicated in cell recognition between synaptic partners, but how these proteins act as a group to specify a complex neural network is poorly understood. Taking advantage of known connectivity in C. elegans, we identified and studied cell adhesion genes expressed in three interacting neurons in the mating circuits of the adult male. Two interacting pairs of cell surface proteins independently promote fasciculation between sensory neuron HOA and its postsynaptic target interneuron AVG: BAM-2/neurexin-related in HOA binds to CASY-1/calsyntenin in AVG; SAX-7/L1CAM in sensory neuron PHC binds to RIG-6/contactin in AVG. A third, basal pathway results in considerable HOA-AVG fasciculation and synapse formation in the absence of the other two. The features of this multiplexed mechanism help to explain how complex connectivity is encoded and robustly established during nervous system development.


Gene expression variation in Drosophila melanogaster due to rare transposable element insertion alleles of large effect.
Transposable elements are a common source of genetic variation that may play a substantial role in contributing to gene expression variation. However, the contribution of transposable elements to expression variation thus far consists of a handful of examples. We used previously published gene expression data from 37 inbred Drosophila melanogaster lines from the Drosophila Genetic Reference Panel to perform a genome-wide assessment of the effects of transposable elements on gene expression. We found thousands of transcripts with transposable element insertions in or near the transcript and that the presence of a transposable element in or near a transcript is significantly associated with reductions in expression. We estimate that within this example population, ∼2.2% of transcripts have a transposable element insertion, which significantly reduces expression in the line containing the transposable element. We also find that transcripts with insertions within 500 bp of the transcript show on average a 0.67 standard deviation decrease in expression level. These large decreases in expression level are most pronounced for transposable element insertions close to transcripts and the effect diminishes for more distant insertions. This work represents the first genome-wide analysis of gene expression variation due to transposable elements and suggests that transposable elements are an important class of mutation underlying expression variation in Drosophila and likely in other systems, given the ubiquity of these mobile elements in eukaryotic genomes.


Extracorporeal Shock-wave Lithotripsy Success Rate and Complications: Initial Experience at Sultan Qaboos University Hospital.
To assess the efficacy and safety of extracorporeal shock wave lithotripsy with Modularis Vario Siemens in the management of patients with renal and ureteral stones. Between 2007 and 2009, 225 outpatients were treated with Siemens Modularis Vario lithotripter at Sultan Qaboos University Hospital. Stone size, location, total number of shockwaves, stone-free rate, complications and adjunctive interventions were investigated. Chi-Square and Logistic Regression analyses were used, with p<0.05 set as the level of significance. Of the 225 initial consecutive patients who underwent extracorporeal shock wave lithotripsy, 192 (85%) had renal stones and 33 (15%) had ureteric stones. The mean±SD stone size was 11.3±4.5 mm, while the mean age of the patients was 39.9±12.8 years with 68.5% males. The mean renal stone size was 11.6±4.7 mm; a mean of 1.3 sessions was required. The mean ureteric stone size was 9.9±3 mm; and a mean of 1.3 sessions was required. Treatment success (defined as complete clearance of ureteric stones, stone-free or clinically insignificant residual fragments of <4 mm for renal stones) was 74% for renal stones and 88% for ureteric stones. Additional extracorporeal shock wave lithotripsy and ureteroscopy were the most adjunctive procedures used for stone clearance. Complications occurred in 74 patients (38.5%) with renal stones and 13 patients (39.4%) with uretetric stones. The most common complication was loin pain (experienced by 16.7% with renal stones and 21% with ureteric stones). Severe renal colic mandating admission occurred in 2% of patients with renal stones and 6% of patients with ureteric stones. In patients with renal stone, steinstrasse occurred in 3.6% and infection post extracorporeal shock wave lithotripsy in 0.5%. Using Multivariate Logistic Regression analysis, factors found to have significant effect on complete stone clearance were serum creatinine (p=0.004) and the number of shockwaves (p=0.021). Siemens Modularis Vario lithotripter is a safe and effective tool for treating renal and ureteric stones.


Redundant and specific roles of cohesin STAG subunits in chromatin looping and transcriptional control.
Cohesin is a ring-shaped multiprotein complex that is crucial for 3D genome organization and transcriptional regulation during differentiation and development. It also confers sister chromatid cohesion and facilitates DNA damage repair. Besides its core subunits SMC3, SMC1A, and RAD21, cohesin in somatic cells contains one of two orthologous STAG subunits, STAG1 or STAG2. How these variable subunits affect the function of the cohesin complex is still unclear. STAG1- and STAG2-cohesin were initially proposed to organize cohesion at telomeres and centromeres, respectively. Here, we uncover redundant and specific roles of STAG1 and STAG2 in gene regulation and chromatin looping using HCT116 cells with an auxin-inducible degron (AID) tag fused to either STAG1 or STAG2. Following rapid depletion of either subunit, we perform high-resolution Hi-C, gene expression, and sequential ChIP studies to show that STAG1 and STAG2 do not co-occupy individual binding sites and have distinct ways by which they affect looping and gene expression. These findings are further supported by single-molecule localizations via direct stochastic optical reconstruction microscopy (dSTORM) super-resolution imaging. Since somatic and congenital mutations of the STAG subunits are associated with cancer (STAG2) and intellectual disability syndromes with congenital abnormalities (STAG1 and STAG2), we verified STAG1-/STAG2-dependencies using human neural stem cells, hence highlighting their importance in particular disease contexts.


Functional analysis of the interdependence between DNA uptake sequence and its cognate ComP receptor during natural transformation in Neisseria species.
Natural transformation is the widespread biological process by which "competent" bacteria take up free DNA, incorporate it into their genomes, and become genetically altered or "transformed". To curb often deleterious transformation by foreign DNA, several competent species preferentially take up their own DNA that contains specific DUS (DNA uptake sequence) watermarks. Our recent finding that ComP is the long sought DUS receptor in Neisseria species paves the way for the functional analysis of the DUS-ComP interdependence which is reported here. By abolishing/modulating ComP levels in Neisseria meningitidis, we show that the enhancement of transformation seen in the presence of DUS is entirely dependent on ComP, which also controls transformation in the absence of DUS. While peripheral bases in the DUS were found to be less important, inner bases are essential since single base mutations led to dramatically impaired interaction with ComP and transformation. Strikingly, naturally occurring DUS variants in the genomes of human Neisseria commensals differing from DUS by only one or two bases were found to be similarly impaired for transformation of N. meningitidis. By showing that ComPsub from the N. subflava commensal specifically binds its cognate DUS variant and mediates DUS-enhanced transformation when expressed in a comP mutant of N. meningitidis, we confirm that a similar mechanism is used by all Neisseria species to promote transformation by their own, or closely related DNA. Together, these findings shed new light on the molecular events involved in the earliest step in natural transformation, and reveal an elegant mechanism for modulating horizontal gene transfer between competent species sharing the same niche.


(-)-Epigallocatechin gallate overcomes resistance to etoposide-induced cell death by targeting the molecular chaperone glucose-regulated protein 78.
Many beneficial properties have been attributed to (-)-epigallocatechin gallate (EGCG), including chemopreventive, anticarcinogenic, and antioxidant actions. In this study, we investigated the effects of EGCG on the function of glucose-regulated protein 78 (GRP78), which is associated with the multidrug resistance phenotype of many types of cancer cells. Our investigation was directed at elucidating the mechanism of the EGCG and GRP78 interaction and providing evidence about whether EGCG modulates the activity of anticancer drugs through the inhibition of GRP78 function. We found that EGCG directly interacted with GRP78 at the ATP-binding site of protein and regulated its function by competing with ATP binding, resulting in the inhibition of ATPase activity. EGCG binding caused the conversion of GRP78 from its active monomer to the inactive dimer and oligomer forms. Further, we showed that EGCG interfered with the formation of the antiapoptotic GRP78-caspase-7 complex, which resulted in an increased etoposide-induced apoptosis in cancer cells. We also showed that EGCG significantly suppressed the transformed phenotype of breast cancer cells treated with etoposide. Overall, these results strongly suggested that EGCG could prevent the antiapoptotic effect of GRP78, which usually suppresses the caspase-mediated cell death pathways in drug-treated cancer cells, contributing to the development of drug resistance.


Identifying differentially methylated sites in samples with varying tumor purity.
DNA methylation aberrations are common in many cancer types. A major challenge hindering comparison of patient-derived samples is that they comprise of heterogeneous collection of cancer and microenvironment cells. We present a computational method that allows comparing cancer methylomes in two or more heterogeneous tumor samples featuring differing, unknown fraction of cancer cells. The method is unique in that it allows comparison also in the absence of normal cell control samples and without prior tumor purity estimates, as these are often unavailable or unreliable in clinical samples. We use simulations and next-generation methylome, RNA and whole-genome sequencing data from two cancer types to demonstrate that the method is accurate and outperforms alternatives. The results show that our method adapts well to various cancer types and to a wide range of tumor content, and works robustly without a control or with controls derived from various sources. The method is freely available at https://bitbucket.org/anthakki/dmml. Supplementary data are available at Bioinformatics online.


Are Guideline-recommended Risk Classification Schemes in Pulmonary Hypertension Adequately Robust to Guide the Real-world Setting?
Pulmonary hypertension is a complex syndrome that encompasses a diverse group of pathophysiologies predisposed by different environmental and genetic factors. It is not clear to which extent the universal risk classification schemes can be applied to cohorts in individual pulmonary hypertension centers with differing environmental backgrounds, genetic pools, referral networks. To explore whether the recommended risk classification schemes could reliably be used for mortality prediction in an unselected pulmonary hypertension population of a tertiary pulmonary hypertension center. A retrospective cross-sectional study. We retrospectively screened our hospital database for the patients with pulmonary hypertension between 2015 and 2022. The grouping of pulmonary hypertension was made as follows in accordance with current guidelines: Group 1: patients with pulmonary arterial hypertension, Group 2: patients with pulmonary hypertension associated with left heart disease, Group 3: patients with pulmonary hypertension associated with lung disease and/or hypoxia, and Group 4: patients with pulmonary hypertension associated with pulmonary artery obstructions. Then, we compared the predicted and observed mortality rates of four different risk classification schemes (REVEAL, REVEAL-Lite, ESC/ERS and COMPERA). We identified 723 cases in our pulmonary hypertension database, the final study population consisted of 549 patients. The REVEAL, REVEAL-Lite and European Society of Cardiology/European Respiratory Society risk scores significantly underestimated the mortality risk in the low-risk stratum (5.3% vs. 1.9%, P < 0.001; 5.3% vs. 2.9%, P = 0.015 and 6.3% vs. 1%, P < 0.001, respectively) and overestimated the mortality risk in the high-risk stratum (11.8% vs. 25.8%, P < 0.001; 10.4% vs. 25.1%, P < 0.001 and 13.2% vs. 30%, P < 0.001, respectively). Although the COMPERA 4-strata model significantly underestimated the risk in low- and intermediate-low risk strata (4.9% vs. 1.5%, P < 0.001 and 6.8% vs. 2.8%, P = 0.001, respectively), it was accurate in intermediate-high and high-risk groups (10.1% vs. 8.7%, P = 0.592 and 15.6% vs. 22%, P = 0.384, respectively). The analyses limited only to group 1 pulmonary hypertension patients gave similar results. The established risk classification schemes may not perform as good as expected in unselected pulmonary hypertension populations and this may have important implications on management decisions. Tertiary centers should not uncritically accept the published risk prediction models and consider modifying current risk scores according to their own patient characteristics.


Phenanthrene Bioavailability and Toxicity to Daphnia magna in the Presence of Carbon Nanotubes with Different Physicochemical Properties.
Studies investigating the effect of carbon nanotubes (CNTs) on the bioavailability and toxicity of hydrophobic organic compounds in aquatic environments have generated contradictory results, and the influence of different CNT properties remains unknown. Here, the adsorption of the polycyclic aromatic hydrocarbon phenanthrene (70-735 μg/L) to five types of CNTs exhibiting different physical and chemical properties was studied. The CNTs were dispersed in the presence of natural organic matter (nominally 20 mg/L) in order to increase the environmental relevance of the study. Furthermore, the bioavailability and toxicity of phenanthrene to Daphnia magna in the absence and presence of dispersed CNTs was investigated. Both CNT dispersion and adsorption of phenanthrene appeared to be influenced by CNT physical properties (diameter and specific surface area). However, dispersion and phenanthrene adsorption was not influenced by CNT surface chemical properties (surface oxygen content), under the conditions tested. Based on nominal phenanthrene concentrations, a reduction in toxicity to D. magna was observed during coexposure to phenanthrene and two types of CNTs, while for the others, no influence on phenanthrene toxicity was observed. Based on freely dissolved concentrations, however, an increased toxicity was observed in the presence of all CNTs, indicating bioavailability of CNT-adsorbed phenanthrene to D. magna.


Inflammasome signaling affects anxiety- and depressive-like behavior and gut microbiome composition.
The inflammasome is hypothesized to be a key mediator of the response to physiological and psychological stressors, and its dysregulation may be implicated in major depressive disorder. Inflammasome activation causes the maturation of caspase-1 and activation of interleukin (IL)-1β and IL-18, two proinflammatory cytokines involved in neuroimmunomodulation, neuroinflammation and neurodegeneration. In this study, C57BL/6 mice with genetic deficiency or pharmacological inhibition of caspase-1 were screened for anxiety- and depressive-like behaviors, and locomotion at baseline and after chronic stress. We found that genetic deficiency of caspase-1 decreased depressive- and anxiety-like behaviors, and conversely increased locomotor activity and skills. Caspase-1 deficiency also prevented the exacerbation of depressive-like behaviors following chronic stress. Furthermore, pharmacological caspase-1 antagonism with minocycline ameliorated stress-induced depressive-like behavior in wild-type mice. Interestingly, chronic stress or pharmacological inhibition of caspase-1 per se altered the fecal microbiome in a very similar manner. When stressed mice were treated with minocycline, the observed gut microbiota changes included increase in relative abundance of Akkermansia spp. and Blautia spp., which are compatible with beneficial effects of attenuated inflammation and rebalance of gut microbiota, respectively, and the increment in Lachnospiracea abundance was consistent with microbiota changes of caspase-1 deficiency. Our results suggest that the protective effect of caspase-1 inhibition involves the modulation of the relationship between stress and gut microbiota composition, and establishes the basis for a gut microbiota-inflammasome-brain axis, whereby the gut microbiota via inflammasome signaling modulate pathways that will alter brain function, and affect depressive- and anxiety-like behaviors. Our data also suggest that further elucidation of the gut microbiota-inflammasome-brain axis may offer novel therapeutic targets for psychiatric disorders.


Traditional use of medicinal plants by the Jaintia tribes in North Cachar Hills district of Assam, northeast India.
The study of ethnobotany relating to any tribe is in itself a very intricate or convoluted process. This paper documents the traditional knowledge of medicinal plants that are in use by the indigenous Jaintia tribes residing in few isolated pockets of northeast India. The present study was done through structured questionnaires in consultations with the tribal practitioners and has resulted in the documentation of 39 medicinal plant species belonging to 27 families and 35 genera. For curing diverse form of ailments, the use of aboveground plant parts was higher (76.59%) than the underground plant parts (23.41%). Of the aboveground plant parts, leaf was used in the majority of cases (23 species), followed by fruit (4). Different underground plant forms such as root, tuber, rhizome, bulb and pseudo-bulb were also found to be in use by the Jaintia tribe as a medicine. Altogether, 30 types of ailments have been reported to be cured by using these 39 medicinal plant species. The study thus underlines the potentials of the ethnobotanical research and the need for the documentation of traditional ecological knowledge pertaining to the medicinal plant utilization for the greater benefit of mankind.


Ethnic variation in gender-STEM stereotypes and STEM participation: an intersectional approach.
Stereotypes associating men and masculine traits with science, technology, engineering, and mathematics (STEM) fields are ubiquitous, but the relative strength of these stereotypes varies considerably across cultures. The present research applies an intersectional approach to understanding ethnic variation in gender-STEM stereotypes and STEM participation within an American university context. African American college women participated in STEM majors at higher rates than European American college women (Study 1, Study 2, and Study 4). Furthermore, African American women had weaker implicit gender-STEM stereotypes than European American women (Studies 2-4), and ethnic differences in implicit gender-STEM stereotypes partially mediated ethnic differences in STEM participation (Study 2 and Study 4). Although African American men had weaker implicit gender-STEM stereotypes than European American men (Study 4), ethnic differences between men in STEM participation were generally small (Study 1) or nonsignificant (Study 4). We discuss the implications of an intersectional approach for understanding the relationship between gender and STEM participation.


Spreading depolarization in the brainstem mediates sudden cardiorespiratory arrest in mouse SUDEP models.
Cardiorespiratory collapse after a seizure is the leading cause of sudden unexpected death in epilepsy (SUDEP) in young persons, but why only certain individuals are at risk is unknown. To identify a mechanism for this lethal cardiorespiratory failure, we examined whether genes linked to increased SUDEP risk lower the threshold for spreading depolarization (SD), a self-propagating depolarizing wave that silences neuronal networks. Mice carrying mutations in Kv1.1 potassium channels (-/-) and Scn1a sodium ion channels (+/R1407X) phenocopy many aspects of human SUDEP. In mutant, but not wild-type mice, seizures initiated by topical application of 4-aminopyridine to the cortex led to a slow, negative DC potential shift recorded in the dorsal medulla, a brainstem region that controls cardiorespiratory pacemaking. This irreversible event slowly depolarized cells and inactivated synaptic activity, producing cardiorespiratory arrest. Local initiation of SD in this region by potassium chloride microinjection also elicited electroencephalographic suppression, apnea, bradycardia, and asystole, similar to the events seen in monitored human SUDEP. In vitro study of brainstem slices confirmed that mutant mice had a lower threshold for SD elicited by metabolic substrate depletion and that immature mice were at greater risk than adults. Deletion of the gene encoding tau, which prolongs life in these mutants, also restored the normal SD threshold in Kv1.1-mutant mouse brainstem. Thus, brainstem SD may be a critical threshold event linking seizures and SUDEP.


Experience with implantable cardioverter-defibrillator therapy in grown-ups with congenital heart disease.
Implantable cardioverter-defibrillators (ICD) are increasingly implanted for primary or secondary prevention of sudden death in young patients with congenital heart disease, cardiomyopathies, or channelopathies. Although major advances in ICD technology and implant techniques have facilitated ICD therapy in young patients, complications such as lead failures, inappropriate shocks, system infections, and negative psychosocial impacts are of concern. The various underlying cardiovascular disease states and a lack of standardized ICD protocols for young patients often necessitate individualized implant techniques, ICD programming, and follow-up. Young ICD patients need a thorough follow-up to ensure adequate therapy, and psychosocial problems have to be addressed.


The experience of a multidisciplinary programme of pulmonary rehabilitation in primary health care from the next of kin's perspective: a qualitative study.
Pulmonary rehabilitation increases functional capacity and quality of life and decrease exacerbations in patients with chronic obstructive pulmonary disease (COPD), but there is little knowledge of how it influences their next of kin. To describe the experience of a multidisciplinary programme of pulmonary rehabilitation in primary health care from the perspective of the next of kin. A descriptive qualitative study was undertaken as part of a longitudinal study comprising a multidisciplinary programme for patients with COPD where the next of kin were invited to one session. Semi-structured interviews were conducted with 20 next of kin and analysed by qualitative content analysis. One main theme emerged - Life still remains overshadowed by illness. There were three sub-themes: a sense of deepened understanding; a sense of personal vulerability; and a sense of relief of burden. The next of kin's life was still overshadowed by illness, despite the multidisciplinary programme. Although experiencing positive outcomes two years after the programme, the next of kin expressed a need for more support. This study has shown that next of kin could benefit from their own participation and/or that of the patient in a multidisciplinary programme of pulmonary rehabilitation. We believe that next of kin should be offered primary health care support for the sake of their own health, but also in order to manage their informal caregiver role. The experiences described here could form a basis for further development of interventions for next of kin of patients with COPD.


ActiveAxADD : Toward non-parametric and orientationally invariant axon diameter distribution mapping using PGSE.
Non-invasive axon diameter distribution (ADD) mapping using diffusion MRI is an ill-posed problem. Current ADD mapping methods require knowledge of axon orientation before performing the acquisition. Instead, ActiveAx uses a 3D sampling scheme to estimate the orientation from the signal, providing orientationally invariant estimates. The mean diameter is estimated instead of the distribution for the solution to be tractable. Here, we propose an extension (ActiveAxADD ) that provides non-parametric and orientationally invariant estimates of the whole distribution. The accelerated microstructure imaging with convex optimization (AMICO) framework accelerates mean diameter estimation using a linear formulation combined with Tikhonov regularization to stabilize the solution. Here, we implement a new formulation (ActiveAxADD ) that uses Laplacian regularization to provide robust estimates of the whole ADD. The performance of ActiveAxADD was evaluated using Monte Carlo simulations on synthetic white matter samples mimicking axon distributions reported in histological studies. ActiveAxADD provided robust ADD reconstructions when considering the isolated intra-axonal signal. However, our formulation inherited some common microstructure imaging limitations. When accounting for the extra axonal compartment, estimated ADDs showed spurious peaks and increased variability because of the difficulty of disentangling intra and extra axonal contributions. Laplacian regularization solves the ill-posedness regarding the intra axonal compartment. ActiveAxADD can potentially provide non-parametric and orientationally invariant ADDs from isolated intra-axonal signals. However, further work is required before ActiveAxADD can be applied to real data containing extra-axonal contributions, as disentangling the 2 compartment appears to be an overlooked challenge that affects microstructure imaging methods in general.


Evaluating genomic tests from bench to bedside: a practical framework.
The development of genomic tests is one of the most significant technological advances in medical testing in recent decades. As these tests become increasingly available, so does the need for a pragmatic framework to evaluate the evidence base and evidence gaps in order to facilitate informed decision-making. In this article we describe such a framework that can provide a common language and benchmarks for different stakeholders of genomic testing. Each stakeholder can use this framework to specify their respective thresholds for decision-making, depending on their perspective and particular needs. This framework is applicable across a broad range of test applications and can be helpful in the application and communication of a regulatory science for genomic testing. Our framework builds upon existing work and incorporates principles familiar to researchers involved in medical testing (both diagnostic and prognostic) generally, as well as those involved in genomic testing. This framework is organized around six phases in the development of genomic tests beginning with marker identification and ending with population impact, and highlights the important knowledge gaps that need to be filled in establishing the clinical relevance of a test. Our framework focuses on the clinical appropriateness of the four main dimensions of test research questions (population/setting, intervention/index test, comparators/reference test, and outcomes) rather than prescribing a hierarchy of study designs that should be used to address each phase.


Spontaneous action potentials and neural coding in unmyelinated axons.
The voltage-gated Na and K channels in neurons are responsible for action potential generation. Because ion channels open and close in a stochastic fashion, spontaneous (ectopic) action potentials can result even in the absence of stimulation. While spontaneous action potentials have been studied in detail in single-compartment models, studies on spatially extended processes have been limited. The simulations and analysis presented here show that spontaneous rate in unmyelinated axon depends nonmonotonically on the length of the axon, that the spontaneous activity has sub-Poisson statistics, and that neural coding can be hampered by the spontaneous spikes by reducing the probability of transmitting the first spike in a train.


Principles of assembly reveal a periodic table of protein complexes.
Structural insights into protein complexes have had a broad impact on our understanding of biological function and evolution. In this work, we sought a comprehensive understanding of the general principles underlying quaternary structure organization in protein complexes. We first examined the fundamental steps by which protein complexes can assemble, using experimental and structure-based characterization of assembly pathways. Most assembly transitions can be classified into three basic types, which can then be used to exhaustively enumerate a large set of possible quaternary structure topologies. These topologies, which include the vast majority of observed protein complex structures, enable a natural organization of protein complexes into a periodic table. On the basis of this table, we can accurately predict the expected frequencies of quaternary structure topologies, including those not yet observed. These results have important implications for quaternary structure prediction, modeling, and engineering.


Neuropsychiatric Symptoms, Endophenotypes, and Syndromes in Late-Onset Alzheimer's Disease: Focus on APOE Gene.
Neuropsychiatric symptoms, previously denominated as behavioural and psychological symptoms of dementia, are common features of Alzheimer's disease (AD) and are one of the major risk factors for institutionalization. At present, the role of the apolipoprotein E (APOE) gene in the development of neuropsychiatric symptoms in AD patients is unclear. In this paper, we summarized the findings of the studies of neuropsychiatric symptoms and neuropsychiatric syndromes/endophenotypes in AD in relation to APOE genotypes, with special attention to the possible underlying mechanisms. While some studies failed to find a significant association between APOE and neuropsychiatric symptoms in late-onset AD, other studies reported a significant association between the APOE ε4 allele and an increase in agitation/aggression, hallucinations, delusions, and late-life depression or anxiety. Furthermore, some negative studies that focused on the distribution of APOE genotypes between AD patients with or without neuropsychiatric symptoms further emphasized the importance of subgrouping neuropsychiatric symptoms in distinct neuropsychiatric syndromes. Explanations for the variable findings in the existing studies included differences in patient populations, differences in the assessment of neuropsychiatric symptomatology, and possible lack of statistical power to detect associations in the negative studies.


Responsive consumerism: empowerment in markets for health plans.
American health policy is increasingly relying on consumerism to improve its performance. This article examines a neglected aspect of medical consumerism: the extent to which consumers respond to problems with their health plans. Using a telephone survey of five thousand consumers conducted in 2002, this article assesses how frequently consumers voice formal grievances or exit from their health plan in response to problems of differing severity. This article also examines the potential impact of this responsiveness on both individuals and the market. In addition, using cross-group comparisons of means and regressions, it looks at how the responses of "empowered" consumers compared with those who are "less empowered." The vast majority of consumers do not formally voice their complaints or exit health plans, even in response to problems with significant consequences. "Empowered" consumers are only minimally more likely to formally voice and no more likely to leave their plan. Moreover, given the greater prevalence of trivial problems, consumers are much more likely to complain or leave their plans because of problems that are not severe. Greater empowerment does not alleviate this. While much of the attention on consumerism has focused on prospective choice, understanding how consumers respond to problems is equally, if not more, important. Relying on consumers' responses as a means to protect individual consumers or influence the market for health plans is unlikely to be successful in its current form.


Valorization of waste micro-algal biomass - collected from coke oven effluent treatment plant and evaluation of sorption potential for fluoride removal.
Fluoride contamination in groundwater is now becoming a global concern. In the present study, removal of fluoride using dry biomass (DBM) of a micro-algal consortium of Chlorococcum infusionum and Leptolyngbya foveolaurum, collected from a coke-oven effluent treatment plant, Durgapur, India, has been investigated. The large volume of algal bloom in the industrial effluent has created serious disposal issues and caused severe environmental concerns. A biosorption technique has been carried out to valorize the waste algae biomass into a potential adsorbent. Response Surface Methodology (RSM) is used to model and optimize fluoride removal. Maximum fluoride removal (72%) is obtained at pH 4, 5 mg/L initial fluoride concentration, 0.5 g/L adsorbent dose (AD), and 25 °C temperature during one-factor-at-a-time (OFAT) analysis. The optimum condition of removal as specified by RSM is - initial concentration of fluoride: 30 mg/L, pH: 4.5, AD: 3.5 g/L and temperature: 30 °C. FESEM-EDX, FTIR and BET isotherm studies are done to characterize raw and fluoride treated biomass. Lagergren first order kinetic model and Freundlich isotherm model, are found to analyze best kinetic and equilibrium data, respectively. Adsorption capacity of DBM has been found to be 34.36 mg/g. The kinetics of fluoride removal have been well described by COMSOL Multiphysics.


Relationship between caseload volume and outcome for systemic lupus erythematosus treatment: the experience of Taiwan.
To determine if a physician's experience or hospital caseload volume is associated with in-hospital mortality of patients with systemic lupus erythematosus (SLE). We used data from Taiwan's National Health Insurance Research Database covering 2002 to 2004. A total of 8536 hospital admissions citing a principal diagnosis of SLE were selected. Hospitals with an average of > 50, 26-50, and < 26 SLE cases per year were categorized as high, medium, and low-caseload-volume hospitals, respectively. Physician caseload volume was defined as low (< 1 SLE case per year), medium (1-3 cases per year), and high-volume (> 3 cases per year). Multivariate logistic regression analyses employing generalized estimated equations were performed to assess the independent association between physician or hospital SLE caseload volume and in-hospital mortality, after adjusting for other factors. We found that in-hospital mortality declined with increasing physician caseload volume (3.0%, 1.0%, and 0.8% for low, medium, and high-volume physicians, respectively), with the adjusted odds of in-hospital mortality for patients treated by low-volume physicians being 2.681 (p < 0.05) times greater than for patients treated by medium-volume physicians, and 3.195 (p < 0.001) times greater than for those treated by high-volume physicians. No significant relationship was found between in-hospital mortality and hospital SLE caseload volume (p = 0.896). We concluded that the factor of physicians' experience treating SLE is more crucial in determining in-hospital mortality than a hospital's annual SLE caseload.


Acuity and case management: a healthy dose of outcomes, part I.
This article presents acuity and dosage as two concepts that describe how the business case for case management (CM) can be made. Dosage and acuity concepts are explained as client need-severity, CM intervention-intensity, and CM activity-dose by amount, duration, extent, and timing. Concepts are related to the practice of CM using evidence-based knowledge and methods to develop instruments that measure and score pivotal CM actions. The purpose of this series of three articles is to introduce the two concepts of dosage and acuity, discuss their importance for making the business case for CM and for translation into evidence-based practice, and present a powerful example of how they can be used in everyday CM. The articles feature a specific exemplar, the CM Acuity Tools project, and explain how the melding of the acuity and dosage innovations will improve the capture of CM outcomes. Part I focuses on the CM Acuity Tool(c) instrument. The article's information applies to all CM practice settings, and contains ideas and recommendations useful to CM generalists, specialists, supervisors, and outcomes managers. The Acuity Tools Project was developed from frontline CM practice in one large, national telephonic CM company. For dosage, the Huber-Hall Dosage Model and its testing are described and explained. The intersection of dosage and acuity is analyzed. For the Acuity Tools Project, a structured literature search and needs assessment launched the development of the suite of acuity tools. The resulting gap analysis identified that an instrument to assign and measure case acuity specific to CM activities was needed. Clinical experts, quality specialists, and business analysts (n = 7) monitored the development and testing of the tools, acuity concepts, scores, differentials, and their operating principles, and evaluated the validity of the acuity tools' content related to CM activities. During the pilot phase of development, interrater reliability testing of draft and final tools for evaluator concordance, beta (beta) testing for content accuracy and appropriateness, and representative sample size testing were done. Expert panel reviews occurred at several junctures along the development pathway, including after initial tool draft and both before and after beta-tests (n = 5) and pilot tests (n = 28). The pilot testing body (n = 33) consisted of a team of case managers (n = 28) along with quality analysts (n = 2), supervisory personnel (n = 2), and the lead product analyst (the developer). Product evaluation included monitoring weekly reports of open cases for the 28 case managers for 3 months (June to August 2000). Positive results generated approval from the expert review panel to apply the suite of acuity tools beyond (1) the initial draft phase, (2) the test population phase, and then (3) at a national CM organization level. This article defines and discusses acuity and dosage as two practical conceptual tools that successfully unite clinical quality and business practices and measure and analyze CM activities. The CM Acuity Tool(c) is a master conceptual framework in three dimensions that synthesizes key components of CM practice, organized into indicators, drivers, and subdrivers. To show value, case managers need to access the evidence base for practice, use tools to capture quantities of intervention-intensity, and specify the activities that produce better outcomes.


Protein microarray characterization of the S-nitrosoproteome.
Nitric oxide (NO) mediates a substantial part of its physiologic functions via S-nitrosylation, however the cellular substrates for NO-mediated S-nitrosylation are largely unknown. Here we describe the S-nitrosoproteome using a high-density protein microarray chip containing 16,368 unique human proteins. We identified 834 potentially S-nitrosylated human proteins. Using a unique and highly specific labeling and affinity capture of S-nitrosylated proteins, 138 cysteine residues on 131 peptides in 95 proteins were determined, defining critical sites of NO's actions. Of these cysteine residues 113 are novel sites of S-nitrosylation. A consensus sequence motif from these 834 proteins for S-nitrosylation was identified, suggesting that the residues flanking the S-nitrosylated cysteine are likely to be the critical determinant of whether the cysteine is S-nitrosylated. We identify eight ubiquitin E3 ligases, RNF10, RNF11, RNF41, RNF141, RNF181, RNF208, WWP2, and UBE3A, whose activities are modulated by S-nitrosylation, providing a unique regulatory mechanism of the ubiquitin proteasome system. These results define a new and extensive set of proteins that are susceptible to NO regulation via S-nitrosylation. Similar approaches could be used to identify other post-translational modification proteomes.


Migraine headaches in chronic fatigue syndrome (CFS): comparison of two prospective cross-sectional studies.
Headaches are more frequent in Chronic Fatigue Syndrome (CFS) than healthy control (HC) subjects. The 2004 International Headache Society (IHS) criteria were used to define CFS headache phenotypes. Subjects in Cohort 1 (HC = 368; CFS = 203) completed questionnaires about many diverse symptoms by giving nominal (yes/no) answers. Cohort 2 (HC = 21; CFS = 67) had more focused evaluations. They scored symptom severities on 0 to 4 anchored ordinal scales, and had structured headache evaluations. All subjects had history and physical examinations; assessments for exclusion criteria; questionnaires about CFS related symptoms (0 to 4 scale), Multidimensional Fatigue Inventory (MFI) and Medical Outcome Survey Short Form 36 (MOS SF-36). Demographics, trends for the number of diffuse "functional" symptoms present, and severity of CFS case designation criteria symptoms were equivalent between CFS subjects in Cohorts 1 and 2. HC had significantly fewer symptoms, lower MFI and higher SF-36 domain scores than CFS in both cohorts. Migraine headaches were found in 84%, and tension-type headaches in 81% of Cohort 2 CFS. This compared to 5% and 45%, respectively, in HC. The CFS group had migraine without aura (60%; MO; CFS+MO), with aura (24%; CFS+MA), tension headaches only (12%), or no headaches (4%). Co-morbid tension and migraine headaches were found in 67% of CFS. CFS+MA had higher severity scores than CFS+MO for the sum of scores for poor memory, dizziness, balance, and numbness ("Neuro-construct", p = 0.002) and perceived heart rhythm disturbances, palpitations and noncardiac chest pain ("Cardio-construct"; p = 0.045, t-tests after Bonferroni corrections). CFS+MO subjects had lower pressure-induced pain thresholds (2.36 kg [1.95-2.78; 95% C.I.] n = 40) and a higher prevalence of fibromyalgia (47%; 1990 criteria) compared to HC (5.23 kg [3.95-6.52] n = 20; and 0%, respectively). Sumatriptan was beneficial for 13 out of 14 newly diagnosed CFS migraine subjects. CFS subjects had higher prevalences of MO and MA than HC, suggesting that mechanisms of migraine pathogenesis such as central sensitization may contribute to CFS pathophysiology. Georgetown University IRB # 2006-481


Sports injuries surveillance during the 2007 IAAF World Athletics Championships.
The aim of this study was to analyze all sports injuries incurred in competitions and/or training during the 2007 World Athletics Championships and to prove the feasibility of the injury surveillance system developed for the 2008 Olympic Games for individual sports. Prospective recording of injuries. 11 IAAF World Championships in Athletics 2007 in Osaka, Japan. All national team physicians and physiotherapists; Local Organising Committee (LOC) physicians working in the Medical Centres at the stadium and warm-up area. Frequency, characteristics, and incidence of injuries. 192 injuries were reported, resulting in an incidence of 97 injuries per 1000 registered athletes. More than half of the injuries (56%) were expected to prevent the athlete from participating in competition or training. Eighty percent affected the lower extremity; the most common diagnosis was thigh strain (16%). In most cases, the injury was caused by overuse (44%). A quarter of the injuries were incurred during training and 137 (71%) in competition. On average, 72.4 injuries per 1000 competing athletes were incurred in competitions. The incidence of injury varied substantially among the disciplines. The risk of a time-loss injury was highest in heptathlon, women's 10,000 m, women's 3000 m steeplechase, decathlon, and men's marathon. The injury surveillance system proved feasible for individual sports. Risk of injury varied among the disciplines, with highest risk in combined disciplines, steeplechase, and long-distance runs. Preventive interventions should mainly focus on overuse injuries and adequate rehabilitation of previous injuries.


Cancer overdiagnosis: a biological challenge and clinical dilemma.
For cancer screening to be successful, it should primarily detect cancers with lethal potential or their precursors early, leading to therapy that reduces mortality and morbidity. Screening programmes have been successful for colon and cervical cancers, where subsequent surgical removal of precursor lesions has resulted in a reduction in cancer incidence and mortality. However, many types of cancer exhibit a range of heterogeneous behaviours and variable likelihoods of progression and death. Consequently, screening for some cancers may have minimal impact on mortality and may do more harm than good. Since the implementation of screening tests for certain cancers (for example, breast and prostate cancers), a spike in incidence of in situ and early-stage cancers has been observed, but a link to reduction in cancer-specific mortality has not been as clear. It is difficult to determine how many of these mortality reductions are due to screening and how many are due to improved treatments of tumours. In cancers with lower incidence but high mortality (for example, pancreatic cancer), screening has focused on high-risk populations, but challenges similar to those for general population screening remain, particularly with regard to finding lesions with difficult-to-characterize malignant potential (for example, intraductal papillary mucinous neoplasms). More sensitive screening methods are detecting smaller and smaller lesions, but this has not been accompanied by a comparable reduction in the incidence of invasive cancers. In this Opinion article, we focus on the contribution of screening in general and high-risk populations to overdiagnosis, the effects of overdiagnosis on patients and emerging strategies to reduce overdiagnosis of indolent cancers through an understanding of tumour heterogeneity, the biology of how cancers evolve and progress, the molecular and cellular features of early neoplasia and the dynamics of the interactions of early lesions with their surrounding tissue microenvironment.


Unilateral incompatibility in Capsicum (Solanaceae): occurrence and taxonomic distribution.
Unilateral incompatibility (UI) occurs when pollinations between species are successful in one direction but not in the other. Self-incompatible (SI) species frequently show UI with genetically related, self-compatible (SC) species, as pollen of SI species is compatible on the SC pistil, but not vice versa. Many examples of unilateral incompatibility, and all those which have been studied most intensively, are found in the Solanaceae, particularly Lycopersicon, Solanum, Nicotiana and Petunia. The genus Capsicum is evolutionarily somewhat distant from Lycopersicon and Solanum and even further removed from Nicotiana and Petunia. Unilateral incompatibility has also been reported in Capsicum; however, this is the first comprehensive study of crosses between all readily available species in the genus. All readily available (wild and domesticated) species in the genus are used as plant material, including the three genera from the Capsicum pubescens complex plus eight other species. Pollinations were made on pot-grown plants in a glasshouse. The number of pistils pollinated per cross varied (from five to 40 pistils per plant), depending on the numbers of flowers available. Pistils were collected 24 h after pollination and fixed for 3-24 h. After staining, pistils were mounted in a drop of stain, squashed gently under a cover slip and examined microscopically under ultra-violet light for pollen tube growth. Unilateral incompatibility is confirmed in the C. pubescens complex. Its direction conforms to that predominant in the Solanaceae and other families, i.e. pistils of self-incompatible species, or self-compatible taxa closely related to self-incompatible species, inhibit pollen tubes of self-compatible species. Unilateral incompatibility in Capsicum does not seem to have arisen to prevent introgression of self-compatibility into self-incompatible taxa, but as a by-product of divergence of the C. pubescens complex from the remainder of the genus.


Osteoporosis: the emperor has no clothes.
Current prevention strategies for low-trauma fractures amongst older persons depend on the notions that fractures are mainly caused by osteoporosis (pathophysiology), that patients at high risk can be identified (screening) and that the risk is amenable to bone-targeted pharmacotherapy (treatment). However, all these three notions can be disputed. Most fracture patients have fallen, but actually do not have osteoporosis. A high likelihood of falling, in turn, is attributable to an ageing-related decline in physical functioning and general frailty. Currently available fracture risk prediction strategies including bone densitometry and multifactorial prediction tools are unable to identify a large proportion of patients who will sustain a fracture, whereas many of those with a high fracture risk score will not sustain a fracture. The evidence for the viability of bone-targeted pharmacotherapy in preventing hip fracture and other clinical fragility fractures is mainly limited to women aged 65-80 years with osteoporosis, whereas the proof of hip fracture-preventing efficacy in women over 80 years of age and in men at all ages is meagre or absent. Further, the antihip fracture efficacy shown in clinical trials is absent in real-life studies. Many drugs for the treatment of osteoporosis have also been associated with increased risks of serious adverse events. There are also considerable uncertainties related to the efficacy of drug therapy in preventing clinical vertebral fractures, whereas the efficacy for preventing other fractures (relative risk reductions of 20-25%) remains moderate, particularly in terms of the low absolute risk reduction in fractures with this treatment.


Detection of the human telomerase RNA component by in situ hybridization in cells from body fluids.
To apply in situ hybridization (ISH) detection of human telomerase reverse transcriptase (hTERT) mRNA expression in abnormal cells in body fluids to evaluate its usefulness in the diagnosis of malignant effusions. We investigated the expression of hTERT mRNA by ISH in 33 fluid samples from 30 patients, including 1 cerebrospinal fluid, 18 pleural fluids, 1 pericardial fluid, 12 peritoneal fluids and 1 bronchial washing. Comparison of the results of ISH with those of conventional cytologic evaluation was also performed. Cytomorphologic examination of the 33 body fluids allowed classification as malignant, suspicious, atypical and benign conditions. Among the 17 malignant conditions, there were 15 cases positive by both cytology and ISH. There were 9 discrepant cytology-ISH results in patients with various conditions, including 2 cases positive by cytology and inconclusive by ISH, 5 cases suspicious by cytology and positive by ISH, and 2 cases atypical by cytology and negative by ISH. Among the 9 benign conditions, there were 8 cases negative by both cytology and ISH and 1 case negative by cytology and positive by ISH. This test was highly sensitive (90%) and specific (91 %) and had favorable positive (95%) and negative (83%) predictive values. Expression of the hTERT mRNA component can be easily detected by ISH in malignant cells from body fluids. This method is especially useful when the abnormal cellpopulation in the fluid consists of limited numbers of suspicious cells that cannot be completely differentiated from reactive mesothelial cells and thus may help differentiate true positive cases from false negative ones. This ISH method for the detection of expression of the hTERT mRNA component may be an ancillary test for early recognition of cancer cells in body fluids and thus has potential as a diagnostic adjunct in cytopathology.


Determining glomerular filtration rate in homozygous sickle cell disease: utility of serum creatinine based estimating equations.
Various estimating equations have been developed to estimate glomerular filtration rate (GFR) for use in clinical practice. However, the unique renal physiological and pathological processes that occur in sickle cell disease (SCD) may invalidate these estimates in this patient population. This study aims to compare GFR estimated using common existing GFR predictive equations to actual measured GFR in persons with homozygous SCD. If the existing equations perform poorly, we propose to develop a new estimating equation for use in persons with SCD. 98 patients with the homozygous SS disease (55 females: 43 males; mean age 34±2.3 years) had serum measurements of creatinine, as well as had GFR measured using (99m)Tc-DTPA nuclear renal scan. GFR was estimated using the Modification of Diet in Renal Disease (MDRD), Cockcroft-Gault (CG), and the serum creatinine based CKD-EPI equations. The Bland-Altman limit of agreement method was used to determine agreement between measured and estimated GFR values. A SCD-specific estimating equation for GFR (JSCCS-GFR equation) was generated by means of multiple regression via backward elimination. The mean measured GFR±SD was 94.9±27.4 mls/min/1.73 m(2) BSA, with a range of 6.4-159.0 mls/min/1.73 m(2). The MDRD and CG equations both overestimated GFR, with the agreement worsening with higher GFR values. The serum creatinine based CKD-EPI equation performed relatively well, but with a systematic bias of about 45 mls/min. The new equation developed resulted in a better fit to our sickle cell disease data than the MDRD equation. Current estimating equations, other than the CKD-EPI equation, do not perform very accurately in persons with homozygous SS disease. A fairly accurate estimating equation, suitable for persons with GFR >60 mls/min/1.73 m(2) has been developed from our dataset and validated within a simulated dataset.


Zoledronic acid treatment of 5T2MM-bearing mice inhibits the development of myeloma bone disease: evidence for decreased osteolysis, tumor burden and angiogenesis, and increased survival.
Multiple myeloma is characterized by the growth of plasma cells in the bone marrow and the development of osteolytic bone disease. Myeloma cells are found closely associated with bone, and targeting this environment may therefore affect both the bone disease and the growth of myeloma cells. We have investigated the effect of the potent bisphosphonate, zoledronic acid, on the development of bone disease, tumor burden, and disease-free survival in the 5T2MM model of myeloma. 5T2MM murine myeloma cells were injected intravenously into C57BL/KaLwRij mice. After 8 weeks, all animals had a paraprotein. Animals were treated with zoledronic acid (120 microg/kg, subcutaneously, twice weekly) or vehicle, from the time of tumor cell injection or from paraprotein detection for 12 or 4 weeks, respectively. All animals injected with tumor cells developed osteolytic lesions, a decrease in cancellous bone volume, an increase in osteoclast perimeter, and a decrease in bone mineral density. Zoledronic acid prevented the formation of lesions, prevented cancellous bone loss and loss of bone mineral density, and reduced osteoclast perimeter. Zoledronic acid also decreased paraprotein concentration, decreased tumor burden, and reduced angiogenesis. In separate experiments, Kaplan-Meier analysis demonstrated a significant increase in survival after treatment with zoledronic acid when compared with control (47 vs. 35 days). A single dose of zoledronic acid was also shown to be effective in preventing the development of osteolytic bone disease. These data show that zoledronic acid is able to prevent the development of osteolytic bone disease, decrease tumor burden in bone, and increase survival in a model of established myeloma.


Oxidative stress in HIV demented patients and protection ex vivo with novel antioxidants.
To determine the role of oxidative stress in mediating HIV dementia and to identify novel therapeutic compounds that may block this oxidative stress. Brain tissue from patients with HIV encephalitis and macaques with simian immune deficiency virus encephalitis was immunostained for lipid peroxidation. Oxidized proteins in CSF of patients with various stages of HIV dementia were quantitated and we determined whether CSF from these patients could alter mitochondrial function. Several novel compounds with antioxidant effects were screened to determine their relative efficacy in protecting against CSF-induced neurotoxicity. Evidence for oxidative stress was present both in brain and in CSF. The presence of oxidized proteins in the CSF and CSF-induced progressive decrease in mitochondrial activity correlated with the severity of cognitive impairment, but only the group of patients with moderate to severe dementia reached statistical significance. L-deprenyl, didox, imidate, diosgenin, and ebselen blocked the CSF-induced toxicity. No effect of trimidox, ruthenium red, or Quercetin was seen. Increased oxidative stress is present in brain and CSF of HIV-infected patients. There is also an accumulation of toxic substances in the CSF that are capable of inducing oxidative stress. The authors have identified several novel compounds that are capable of blocking the CSF-induced toxicity, the therapeutic potential of which is worthy of further exploration.


Reciprocal chromosome painting among human, aardvark, and elephant (superorder Afrotheria) reveals the likely eutherian ancestral karyotype.
The Afrotheria, a supraordinal grouping of mammals whose radiation is rooted in Africa, is strongly supported by DNA sequence data but not by their disparate anatomical features. We have used flow-sorted human, aardvark, and African elephant chromosome painting probes and applied reciprocal painting schemes to representatives of two of the Afrotherian orders, the Tubulidentata (aardvark) and Proboscidea (elephants), in an attempt to shed additional light on the evolutionary affinities of this enigmatic group of mammals. Although we have not yet found any unique cytogenetic signatures that support the monophyly of the Afrotheria, embedded within the aardvark genome we find the strongest evidence yet of a mammalian ancestral karyotype comprising 2n = 44. This karyotype includes nine chromosomes that show complete conserved synteny to those of man, six that show conservation as single chromosome arms or blocks in the human karyotype but that occur on two different chromosomes in the ancestor, and seven neighbor-joining combinations (i.e., the synteny is maintained in the majority of species of the orders studied so far, but which corresponds to two chromosomes in humans). The comparative chromosome maps presented between human and these Afrotherian species provide further insight into mammalian genome organization and comparative genomic data for the Afrotheria, one of the four major evolutionary clades postulated for the Eutheria.


Pseudoarthrosis of second metatarsal fracture.
Metatarsal fractures make up the greatest portion of foot fractures in children. Most of them are treated with closed reduction and non-weightbearing cast immobilization.Usually, these fractures heal uneventfully and delay union and pseudoarthrosis are rare. We report a case of a 10-year-old child with non-union of the second metatarsal following a traumatic fracture, caused by an accident 10 months before, and treated successfully by osteosynthesis with plate and screws. Good clinical outcome was achieved at 2 years follow-up.


Rapid detection of multiple respiratory viruses based on microfluidic isothermal amplification and a real-time colorimetric method.
Respiratory viruses are major threats causing development of acute respiratory tract infections, which are common causes of illness and death throughout the world. Here, an integrated microsystem based on real-time colorimetry was developed for diagnosing multiple respiratory viruses. The microsystem employed magnetic beads for nucleic acid extraction and an eight-channel microfluidic array chip integrated with a loop-mediated isothermal amplification system for point-of-care screening of respiratory viruses. The overall detection process (including sample collection, nucleic acid extraction, sample loading, real-time detection, and signal output) could be completed within 1 h. Our results show that the developed method could specifically recognize influenza A virus subtypes (H1N1, H3N2, H5N1, and H7N9), influenza B virus, and human adenoviruses. The results obtained with 109 clinical samples indicate that the developed method has high specificity (100%, confidence interval 94.9-100.0) and sensitivity (96%, confidence interval 78.1-99.9). The integration of magnetic bead-based pre-treatment techniques and microfluidic isothermal amplification provides an effective solution for rapidly detecting etiological agents of respiratory diseases. The strategy of using a closed chip system and real-time colorimetry reduced aerosol contamination and ensured the accuracy of the results. The developed method provides an effective alternative for rapid point-of-care screening for viruses that cause respiratory disease syndromes and further aids in accurate and timely detection to control and prevent the spread of respiratory diseases caused by such pathogens.


Limitations of the usual blood-pressure hypothesis and importance of variability, instability, and episodic hypertension.
Although hypertension is the most prevalent treatable vascular risk factor, how it causes end-organ damage and vascular events is poorly understood. Yet, a widespread belief exists that underlying usual blood pressure can alone account for all blood-pressure-related risk of vascular events and for the benefits of antihypertensive drugs, and this notion has come to underpin all major clinical guidelines on diagnosis and treatment of hypertension. Other potentially informative measures, such as variability in clinic blood pressure or maximum blood pressure reached, have been neglected, and effects of antihypertensive drugs on such measures are largely unknown. Clinical guidelines recommend that episodic hypertension is not treated, and the potential risks of residual variability in blood pressure in treated hypertensive patients have been ignored. This Review discusses shortcomings of the usual blood-pressure hypothesis, provides background to accompanying reports on the importance of blood-pressure variability in prediction of risk of vascular events and in accounting for benefits of antihypertensive drugs, and draws attention to clinical implications and directions for future research.


[Predictive value of dipyridamole myocardial perfusion tomography on survival].
Dipyridamole (DIP) is the most commonly employed pharmacological stressor for myocardial perfusion tomography (SPECT) in patients unable to reach an adequate work load. To assess the predictive capacity of DIP SPECT on survival. We included 985 adults aged 66 ±11 years (45% women) with rest and DIP-SPECT. The main indications for the procedure were coronary artery disease (CAD) screening in 66% and known CAD in 33%. Participants were followed up for a median of 65 months (interquartile range 54 to 86 months). During the follow up, 261 deaths were recorded and 98% had a specified cause in their death certificate. Myocardial SPECT was abnormal in 44% of participants. Transient ischemic defects were observed in 34%, fixed defects concordant with infarction in 27% and post-stress systolic dysfunction in 23%. Twenty five percent of deaths were attributable to cardiac or ischemic cause and 22% to cancer. In a bivariate analysis, the hazard ratio (HR) of death of any cause was lower in females and higher in the presence of CAD. The multivariate analysis showed that being older than 46 years increased the HR of death of any cause. In a bivariate analysis, the HR for cardiac death was higher when the myocardial SPECT showed ischemia, necrosis or left ventricular dilation. In the multivariate analysis, post-stress left ventricular systolic function was associated with a lower risk of cardiac death. An abnormal myocardial SPECT, perfusion abnormalities, left ventricular systolic function or dilation are independent predictors of cardiac death in these participants.


Vascular endothelial growth factor gene polymorphisms in giant cell arteritis.
To examine potential associations of vascular endothelial growth factor (VEGF) gene polymorphisms with giant cell arteritis (GCA) and disease expression, in particular in patients with and without ischemic complications. We enrolled 92 consecutive patients with biopsy-proven GCA residing in Reggio Emilia, Italy. Two hundred healthy blood donors from the same geographic area were selected as controls. All the GCA patients and controls were genotyped by polymerase chain reaction and allele-specific oligonucleotide techniques for 936 C/T and 634 C/G mutations and for an 18 bp insertion/deletion (I/D) polymorphism in the VEGF promoter region. In vitro release of VEGF by peripheral blood mononuclear cells (PBMC) was investigated by ELISA in controls homozygous for the polymorphisms studied. The carriage rates of the alleles I and C634 were significantly more frequent in GCA patients than in controls (p = 0.025, OR 1.9, 95% CI 1.1-3.1 and p = 0.015, OR 2.1, 95% CI 1.1-3.6, respectively). The distribution of allele T936 was similar in GCA patients and controls. No significant differences in the distribution of the polymorphisms studied were observed in patients with ischemic manifestations compared to those without ischemic manifestations. Lipopolysaccharide (LPS)-stimulated VEGF production by PBMC from controls was higher in II homozygous compared to DD homozygous patients. Our data indicate that carriers of C634 and I alleles are associated with susceptibility to developing GCA.


Polymorphism in Plastosciara perniciosa.
Two widely divergent morphotypes of both adult males and adult females were found in laboratory colonies of Plastosciara perniciosa in Hawaii. Extraordinary modification of all features except the genitalia, with associated behavioral differences, enables the micropterous morphotype to take maximum advantage of a stable larval habitat. Capabilities for migration from adverse habitats, dispersal, and maintenance of gene flow are retained in the macropterous morphotype.


Heterogeneity prevails: the state of clinical trial data management in Europe - results of a survey of ECRIN centres.
The use of Clinical Data Management Systems (CDMS) has become essential in clinical trials to handle the increasing amount of data that must be collected and analyzed. With a CDMS trial data are captured at investigator sites with "electronic Case Report Forms". Although more and more of these electronic data management systems are used in academic research centres an overview of CDMS products and of available data management and quality management resources for academic clinical trials in Europe is missing. The ECRIN (European Clinical Research Infrastructure Network) data management working group conducted a two-part standardized survey on data management, software tools, and quality management for clinical trials. The questionnaires were answered by nearly 80 centres/units (with an overall response rate of 47% and 43%) from 12 European countries and EORTC. Our survey shows that about 90% of centres have a CDMS in routine use. Of these CDMS nearly 50% are commercial systems; Open Source solutions don't play a major role. In general, solutions used for clinical data management are very heterogeneous: 20 different commercial CDMS products (7 Open Source solutions) in addition to 17/18 proprietary systems are in use. The most widely employed CDMS products are MACRO and Capture System, followed by solutions that are used in at least 3 centres: eResearch Network, CleanWeb, GCP Base and SAS. Although quality management systems for data management are in place in most centres/units, there exist some deficits in the area of system validation. Because the considerable heterogeneity of data management software solutions may be a hindrance to cooperation based on trial data exchange, standards like CDISC (Clinical Data Interchange Standard Consortium) should be implemented more widely. In a heterogeneous environment the use of data standards can simplify data exchange, increase the quality of data and prepare centres for new developments (e.g. the use of EHR for clinical research). Because data management and the use of electronic data capture systems in clinical trials are characterized by the impact of regulations and guidelines, ethical concerns are discussed. In this context quality management becomes an important part of compliant data management. To address these issues ECRIN will establish certified data centres to support electronic data management and associated compliance needs of clinical trial centres in Europe.


MITK-OpenIGTLink for combining open-source toolkits in real-time computer-assisted interventions.
Due to rapid developments in the research areas of medical imaging, medical image processing and robotics, computer-assisted interventions (CAI) are becoming an integral part of modern patient care. From a software engineering point of view, these systems are highly complex and research can benefit greatly from reusing software components. This is supported by a number of open-source toolkits for medical imaging and CAI such as the medical imaging interaction toolkit (MITK), the public software library for ultrasound imaging research (PLUS) and 3D Slicer. An independent inter-toolkit communication such as the open image-guided therapy link (OpenIGTLink) can be used to combine the advantages of these toolkits and enable an easier realization of a clinical CAI workflow. MITK-OpenIGTLink is presented as a network interface within MITK that allows easy to use, asynchronous two-way messaging between MITK and clinical devices or other toolkits. Performance and interoperability tests with MITK-OpenIGTLink were carried out considering the whole CAI workflow from data acquisition over processing to visualization. We present how MITK-OpenIGTLink can be applied in different usage scenarios. In performance tests, tracking data were transmitted with a frame rate of up to 1000 Hz and a latency of 2.81 ms. Transmission of images with typical ultrasound (US) and greyscale high-definition (HD) resolutions of [Formula: see text] and [Formula: see text] is possible at up to 512 and 128 Hz, respectively. With the integration of OpenIGTLink into MITK, this protocol is now supported by all established open-source toolkits in the field. This eases interoperability between MITK and toolkits such as PLUS or 3D Slicer and facilitates cross-toolkit research collaborations. MITK and its submodule MITK-OpenIGTLink are provided open source under a BSD-style licence ( http://mitk.org ).


Structure of a murine cytoplasmic serine hydroxymethyltransferase quinonoid ternary complex: evidence for asymmetric obligate dimers.
Serine hydroxymethyltransferase (SHMT) is a pyridoxal phosphate-dependent enzyme that catalyzes the reversible conversion of serine and tetrahydrofolate to glycine and methylenetetrahydrofolate. This reaction generates single carbon units for purine, thymidine, and methionine biosynthesis. The enzyme is a homotetramer comprising two obligate dimers and four pyridoxal phosphate-bound active sites. The mammalian enzyme is present in cells in both catalytically active and inactive forms. The inactive form is a ternary complex that results from the binding of glycine and 5-formyltetrahydrofolate polyglutamate, a slow tight-binding inhibitor. The crystal structure of a close analogue of the inactive form of murine cytoplasmic SHMT (cSHMT), lacking only the polyglutamate tail of the inhibitor, has been determined to 2.9 A resolution. This first structure of a ligand-bound mammalian SHMT allows identification of amino acid residues involved in substrate binding and catalysis. It also reveals that the two obligate dimers making up a tetramer are not equivalent; one can be described as "tight-binding" and the other as "loose-binding" for folate. Both active sites of the tight-binding dimer are occupied by 5-formyltetrahydrofolate (5-formylTHF), whose N5-formyl carbon is within 4 A of the glycine alpha-carbon of the glycine-pyridoxal phosphate complex; the complex appears to be primarily in its quinonoid form. In the loose-binding dimer, 5-formylTHF is present in only one of the active sites, and its N5-formyl carbon is 5 A from the glycine alpha-carbon. The pyridoxal phosphates appear to be primarily present as geminal diamine complexes, with bonds to both glycine and the active site lysine. This structure suggests that only two of the four catalytic sites on SHMT are catalytically competent and that the cSHMT-glycine-5-formylTHF ternary complex is an intermediate state analogue of the catalytic complex associated with serine and glycine interconversion.


An Open-Publishing Response to the COVID-19 Infodemic.
The COVID-19 pandemic catalyzed the rapid dissemination of papers and preprints investigating the disease and its associated virus, SARS-CoV-2. The multifaceted nature of COVID-19 demands a multidisciplinary approach, but the urgency of the crisis combined with the need for social distancing measures present unique challenges to collaborative science. We applied a massive online open publishing approach to this problem using Manubot. Through GitHub, collaborators summarized and critiqued COVID-19 literature, creating a review manuscript. Manubot automatically compiled citation information for referenced preprints, journal publications, websites, and clinical trials. Continuous integration workflows retrieved up-to-date data from online sources nightly, regenerating some of the manuscript's figures and statistics. Manubot rendered the manuscript into PDF, HTML, LaTeX, and DOCX outputs, immediately updating the version available online upon the integration of new content. Through this effort, we organized over 50 scientists from a range of backgrounds who evaluated over 1,500 sources and developed seven literature reviews. While many efforts from the computational community have focused on mining COVID-19 literature, our project illustrates the power of open publishing to organize both technical and non-technical scientists to aggregate and disseminate information in response to an evolving crisis.


An evidence-based decision assistance model for predicting training outcome in juvenile guide dogs.
Working dog organisations, such as Guide Dogs, need to regularly assess the behaviour of the dogs they train. In this study we developed a questionnaire-style behaviour assessment completed by training supervisors of juvenile guide dogs aged 5, 8 and 12 months old (n = 1,401), and evaluated aspects of its reliability and validity. Specifically, internal reliability, temporal consistency, construct validity, predictive criterion validity (comparing against later training outcome) and concurrent criterion validity (comparing against a standardised behaviour test) were evaluated. Thirty-nine questions were sourced either from previously published literature or created to meet requirements identified via Guide Dogs staff surveys and staff feedback. Internal reliability analyses revealed seven reliable and interpretable trait scales named according to the questions within them as: Adaptability; Body Sensitivity; Distractibility; Excitability; General Anxiety; Trainability and Stair Anxiety. Intra-individual temporal consistency of the scale scores between 5-8, 8-12 and 5-12 months was high. All scales excepting Body Sensitivity showed some degree of concurrent criterion validity. Predictive criterion validity was supported for all seven scales, since associations were found with training outcome, at at-least one age. Thresholds of z-scores on the scales were identified that were able to distinguish later training outcome by identifying 8.4% of all dogs withdrawn for behaviour and 8.5% of all qualified dogs, with 84% and 85% specificity. The questionnaire assessment was reliable and could detect traits that are consistent within individuals over time, despite juvenile dogs undergoing development during the study period. By applying thresholds to scores produced from the questionnaire this assessment could prove to be a highly valuable decision-making tool for Guide Dogs. This is the first questionnaire-style assessment of juvenile dogs that has shown value in predicting the training outcome of individual working dogs.


Species boundaries in the Astragalus cusickii complex delimited using molecular phylogenetic techniques.
Understanding the source of phenotypic variability is a challenge in the biological sciences. Variation in phenotypes is the result of variation in the genetics and environment the organism experiences, but elucidating the relative contribution of these two parameters can pose problems, especially in the field of systematics. Systematists are challenged to classify biological diversity into groups that share common ancestry. Phenotypic variation can be useful to demonstrate common ancestry, but only when the primary contributor to the variation is under strong genetic control, and thus heritable. Cusick's milkvetch (Astragalus cusickii) is a perennial forb endemic to the northwestern intermountain region of the United States. The species currently comprises four varieties based on subtle morphological dissimilarities, such as leaf size and density, and the size and shape of the seed pods. The taxonomic organization of the varieties of A. cusickii and related species of Astragalus were reexamined through phylogenetic analysis of low copy nuclear, nuclear-ribosomal, and chloroplast gene regions. Maximum parsimony, maximum likelihood, Bayesian inference, the genealogical sorting index, and an approximately unbiased test were used to determine appropriate species boundaries under the phylogenetic species concept. The results support reclassification of A. cusickii var. packardiae and A. cusickii var. sterilis as separate species. Additionally, evidence suggests a chloroplast capture event may have occurred in one population of A. cusickii var. packardiae.


Imidazolium-based poly(ionic liquid)s as new alternatives for CO2 capture.
Solid imidazolium-based poly(ionic liquid)s with variable molecular weights that contain the poly[2-(1-butylimidazolium-3-yl)ethyl methacrylate] (BIEMA) cation and different counter anions were evaluated in terms of CO2 capture and compared with classical ionic liquids with similar counter anions. In addition to poly(ionic liquid)s with often-applied ions such as BF4 (-) , PF6 (-) , NTf2 (-) , trifluoromethanesulfonate (OTf(-) ) and Br(-) , for the first time [BIEMA][acetate] was synthesised, which revealed a remarkably high CO2 sorption performance that exceeded the poly(ionic liquid)s studied previously on average by a factor of four (12.46 mg gPIL (-1) ). This study provides an understanding of the factors that affect CO2 sorption and a comparison of the CO2 capture efficiency with the frequently used sorbents. Moreover, all the studied sorbents were reusable if regenerated under carefully selected conditions and can be considered as suitable candidates for CO2 sorption.


A decade of reversal: an analysis of 146 contradicted medical practices.
To identify medical practices that offer no net benefits. We reviewed all original articles published in 10 years (2001-2010) in one high-impact journal. Articles were classified on the basis of whether they addressed a medical practice, whether they tested a new or existing therapy, and whether results were positive or negative. Articles were then classified as 1 of 4 types: replacement, when a new practice surpasses standard of care; back to the drawing board, when a new practice is no better than current practice; reaffirmation, when an existing practice is found to be better than a lesser standard; and reversal, when an existing practice is found to be no better than a lesser therapy. This study was conducted from August 1, 2011, through October 31, 2012. We reviewed 2044 original articles, 1344 of which concerned a medical practice. Of these, 981 articles (73.0%) examined a new medical practice, whereas 363 (27.0%) tested an established practice. A total of 947 studies (70.5%) had positive findings, whereas 397 (29.5%) reached a negative conclusion. A total of 756 articles addressing a medical practice constituted replacement, 165 were back to the drawing board, 146 were medical reversals, 138 were reaffirmations, and 139 were inconclusive. Of the 363 articles testing standard of care, 146 (40.2%) reversed that practice, whereas 138 (38.0%) reaffirmed it. The reversal of established medical practice is common and occurs across all classes of medical practice. This investigation sheds light on low-value practices and patterns of medical research.


Factors associated with radiation therapy incidents in a large academic institution.
This study evaluated factors associated with radiation therapy (RT) planning and delivery incidents at a large academic institution. The RT incidents (including near-misses) were recorded using an electronic incident reporting system from April 1, 2011 to April 30, 2013. Each incident's origin was categorized according to the step in the treatment process (simulation, physician prescription, treatment planning, scheduling, treatment delivery, and other) in which it occurred. The incident database was linked to the RT delivery (record and verify) database to evaluate the effect of various factors on the rate of RT incidents. There were 189 reported RT incidents (including near-misses) among 326,448 fractions, of which there were 70 (37%) treatment planning incidents and 56 (30%) treatment delivery incidents. The rates of total incidents, planning incidents, and delivery incidents were 136.0, 50.4, and 40.3 per 10,000 patients, respectively. Logistic multivariate analysis showed that fewer work days from plan approval to treatment start, fewer fractions, higher number of prescription items, and longer beam duration were significantly associated with radiation planning incidents. Multivariate analysis also showed that first day of treatment, fewer fractions, higher number of prescription items, and longer beam duration were significantly associated with treatment delivery incidents; intensity modulated radiation therapy was associated with a lower rate of treatment delivery incidents. More complicated radiation plans, fewer fractions, first day of treatment, and rushed processes were associated with higher risk of RT incidents. We hope that a national incident reporting database will lead to greater understanding of factors influencing the rate of RT incidents.


Do reef corals age?
Hydra is emerging as a model organism for studies of ageing in early metazoan animals, but reef corals offer an equally ancient evolutionary perspective as well as several advantages, not least being the hard exoskeleton which provides a rich fossil record as well as a record of growth and means of ageing of individual coral polyps. Reef corals are also widely regarded as potentially immortal at the level of the asexual lineage and are assumed not to undergo an intrinsic ageing process. However, putative molecular indicators of ageing have recently been detected in reef corals. While many of the large massive coral species attain considerable ages (>600 years) there are other much shorter-lived species where older members of some populations show catastrophic mortality, compared to juveniles, under environmental stress. Other studies suggestive of ageing include those demonstrating decreased reproduction, increased susceptibility to oxidative stress and disease, reduced regeneration potential and declining growth rate in mature colonies. This review aims to promote interest and research in reef coral ageing, both as a useful model for the early evolution of ageing and as a factor in studies of ecological impacts on reef systems in light of the enhanced effects of environmental stress on ageing in other organisms.


Judges' assumptions about the appropriateness of civil and forensic commitment.
The study examined judges' reasons for ordering pretrial forensic evaluation instead of civil commitment for persons with mental illness who are arrested. Fifty-five of 58 judges acknowledged having concerns about the adequacy of treatment or confinement in the civil mental health system, and 31 reported ordering pretrial forensic evaluations as a means of ensuring adequate treatment for patients who appear in their courts. Other frequently endorsed reasons for ordering these evaluations included lack of confidence in the ability to civilly commit mentally ill offenders and concerns about their being discharged prematurely. This study confirms suspicions that judges order pretrial evaluations to fill perceived gaps in the civil system.


White matter hemodynamic abnormalities precede sub-cortical gray matter changes in multiple sclerosis.
Hypoperfusion has been reported in lesions, normal-appearing white (NAWM) and gray matter (NAGM) of patients with clinically definite multiple sclerosis (MS) by using perfusion MRI. However, it is still unknown how early such changes in perfusion occur. The aim of our study was to assess the presence of hemodynamic changes in the NAWM and subcortical NAGM of patients with clinically isolated syndrome (CIS) in comparison to healthy controls and to patients with early relapsing-remitting (RR) MS. Absolute cerebral blood flow (CBF), blood volume (CBV) and mean transit time (MTT) were measured in the periventricular and frontal NAWM, thalamus and putamen nuclei of 12 patients with CIS, 12 with early RR-MS and 12 healthy controls using dynamic susceptibility contrast enhanced (DSC) T2*-weighted MRI. Compared to controls, CBF was significantly decreased in the periventricular NAWM of CIS patients and in the periventricular NAWM and putamen of RR-MS patients. Compared to CIS, RR-MS patients showed a significant CBF decrease in the putamen. CBF was decreased in the NAWM of both CIS and RR-MS patients and in the subcortical NAGM of RR-MS patients suggesting a continuum of tissue perfusion decreases beginning in white matter and spreading to gray matter, as the disease progresses.


Analysis of IL-6-mediated growth control of myeloma cells using a gp130 chimeric receptor approach.
Interleukin 6 (IL-6) has been shown to be a key growth factor for myeloma cells. To study IL-6 signal transduction in multiple myeloma (MM), we employed chimeric receptors composed of the epidermal growth factor receptor (EGFR) extracellular domain, gp130 transmembrane domain, and full-length or truncated gp130 cytoplasmic domains lacking regions previously shown to be necessary for MAPK, STAT1, and STAT3 activation. The IL-6-dependent KAS-6/1 MM cell line was transfected with various chimeric receptor constructs and assayed for EGF responsiveness. EGF stimulation surprisingly stimulated DNA synthesis in all transfectants, regardless of receptor length. When cell proliferation was assayed instead, only transfectants capable of inducing high levels of STAT3 activation proliferated in response to EGF. Additional studies revealed that EGF stimulation resulted in tyrosine phosphorylation of endogenous gp130 in cells expressing the chimeric receptor. Replacing the gp130 transmembrane region with the EGFR transmembrane domain diminished but did not disrupt this interaction. This receptor interaction was also observed in the IL-6-dependent MM cell line ANBL-6. In summary, although our results suggest that STAT activation is crucial in gp130-mediated proliferation of myeloma cells, these results must be interpreted with caution given our demonstration of the interaction between chimeric and endogenous receptors in myeloma cells. Importantly, this interaction has not been noted in studies utilizing the same gp130 chimeric receptor system in non-MM cells.


Mapping brain structural differences and neuroreceptor correlates in Parkinson's disease visual hallucinations.
Parkinson's psychosis (PDP) describes a spectrum of symptoms that may arise in Parkinson's disease (PD) including visual hallucinations (VH). Imaging studies investigating the neural correlates of PDP have been inconsistent in their findings, due to differences in study design and limitations of scale. Here we use empirical Bayes harmonisation to pool together structural imaging data from multiple research groups into a large-scale mega-analysis, allowing us to identify cortical regions and networks involved in VH and their relation to receptor binding. Differences of morphometrics analysed show a wider cortical involvement underlying VH than previously recognised, including primary visual cortex and surrounding regions, and the hippocampus, independent of its role in cognitive decline. Structural covariance analyses point to the involvement of the attentional control networks in PD-VH, while associations with receptor density maps suggest neurotransmitter loss may be linked to the cortical changes.


A combination of IL-10 and direct contact with plasma cell tumors decreases CD23 expression on splenic B cells.
We and others have previously found that splenic B cells from plasma cell tumor-bearing mice exhibit decreased CD23 expression. In the present study we further examined the mechanism of CD23 down-regulation by plasma cell tumors. We show here that although direct contact is required between the tumor cells and B cells, it is not sufficient, since fixed tumor cells do not induce the same reduction in CD23 expression. We have identified IL-10, a cytokine produce by the tumors, as the sole soluble factor that contributes to decreased CD23 expression on B cells induced by plasma cell tumors because 1) Abs to IL-10 prevent the loss of CD23 induced by plasma cell tumors both in vitro and in vivo; 2) engineered IL-10 negative variants of these tumors are reduced in their ability to down-regulate CD23 expression; 3) rIL-10 alone induces partial, but significant, decreases in CD23 expression on normal splenic B cells; and 4) the addition of IL-10 and fixed tumor cells to cultures of normal splenocytes decreases CD23 expression to levels similar to those in cocultures with live tumor cells. Collectively, these results demonstrate that plasma cell tumors down-regulate CD23 expression on B cells by a coordinate mechanism of IL-10 plus contact-mediated events and reveal a novel role for IL-10 in the regulation of CD23 expression on B cells that is suggestive of host B cell activation in the presence of the tumor.