The invention comprises a novel lactate compound for two unique purposes: (1) cardiac energy resuscitation and the treatment or prevention of reperfusion injury following ischemia, and (2) the provision of a fuel energy source to humans and other mammals during exercise and recovery. The novel lactate compound is particularly a lactate thiolester. Preferably, the thiol is selected from a cysteine or a methionine amino acid. In a particularly preferred form, the compound is a lactate N-acetyl ethyl ester of the cysteine or methionine amino acid. The most preferred compound is lactate N-acetyl cysteine thiolester (LNACE):

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Apstein, C. S., and L. H. Opie. Glucose-insulin-potassium (GIK) for acute myocardial infarction: a negative study with a positive value. Cardiovasc. Drugs Ther. 13: 185-189, 1999.
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This invention relates generally to parenteral and enteral energy supplements, and, in particular, to a novel method and composition beneficial to functioning of heart and skeletal muscles of mammals with carbohydrate energy forms, antioxidants and electrolytes during ischemic and exercise stresses and subsequent recovery.
This invention relates to a new lactate compound and a method of: (1) cardiac energy resuscitation and treating ischemia in mammalian hearts, lungs, veins, arteries and other organs or tissues, and (2) providing a supplemental energy source to active persons during exercise and recovery from exercise, and (3) providing energy to the heart and skeletal muscles during physical exercise and recovery from exercise. The invention is particularly directed to: (1) a method of cardiac energy resuscitation and treating an organ depleted of oxygen with a therapeutic amount of the novel lactate compound, (2) a method of replenishing energy in active individuals, (3) a method of maintaining blood sugar (glucose) in exercising individuals and restoring liver carbohydrate stores (glycogen) during recovery from exercise, and a method of hydrating and rehydrating individuals during exercise and recovery. The inventive method is constructed to benefit: (1) cardiac energy resuscitation following relief of cardiac ischemia as well as increase the viability of transplanted organs, and (2) increase the energy supply and vigor of active individuals.
The invention takes advantage of discoveries of the classic (cell-cell, organ-organ) xe2x80x9cLactate Shuttle,xe2x80x9d and the xe2x80x9cIntracellular Lactate Shuttlexe2x80x9d mechanisms by Brooks (1984, 1998). The xe2x80x9cLactate Shuttle Hypothesisxe2x80x9d holds that lactate plays a key role in the distribution of carbohydrate potential energy which occurs among various tissue and cellular compartments such as between: cytosol and mitochondria, muscle and blood, blood and muscle, active and inactive muscles, white and red muscles, blood and heart, arterial blood and liver, liver and other tissues such as exercising muscle, intestine and portal blood, portal blood and liver, zones of the liver, skin and blood, and astrocytes and neurons in the brain. Studies on resting and exercising humans indicate that most lactate (70-80%) is disposed of through oxidation, with much of the remainder converted to glucose and glycogen. Studies on canine muscles made to contract in situ also yield the result that lactate is rapidly oxidized (Gladden et al.). Lactate transport across cellular membranes occurs by means of facilitated exchange along pH and concentration gradients (Roth and Brooks 1990a, 1990b) involving a family of lactate transport proteins now called monocarboxylate transporters (MCT""s) (Garcia et al., 1994; Price et al., 1998). Current evidence is that muscle and other cell membrane lactate transporters are abundant with characteristics of high Km and Vmax. There appears to be long-term plasticity in the number of cell membrane transporters, but short-term regulation by allosteric modulation or phosphorylation is not known to occur.
Key to recognition of an xe2x80x9cIntracellular Lactate Shuttlexe2x80x9d was recognition that in addition to cell membranes, mitochondria also contain monocarboxylate transporters (mMCT) and lactic dehydrogenase (mLDH). Mitochondrial MCT""s exist in the mitochondrial inner membrane, and possibly also the outer membrane (FIG. 1), although presence of an outer mitochondrial membrane MCT is not essential because it is highly permeable. The Intracellular Lactate Shuttle also requires presence of mitochondrial lactate dehydrogenase (mLDH) located on the inner membrane and in the intra-membrane (periplasmic) mitochondrial space. mLDH is necessary to convert lactate, the predominant plasma and intracellular monocarboxylate, to pyruvate, for transport via mMCT into the mitochondrial matrix for catalysis by pyruvate dehydrogenase (PDH) and entry into the tricarboxylic acid (TCA) cycle. Therefore, mitochondrial monocarboxylate uptake and oxidation, rather than translocation of transporters to the cell surfaces, regulate lactate flux in vivo. Key discoveries in basic science are that lactate enters mitochondria, but that pyruvate is oxidized in the mitochondrial matrix. To take advantage of the Intracellular Lactate Shuttle, the invention described herein provides a means of delivering the energy fuel source, lactate, to working and stressed heart and muscle tissues. Key to the invention is providing a non-acidic lactate carrier molecule that has the advantage of being an effective antioxidant.
(1) Use of Lactate Thiolester for the Cardiac Energy Resuscitation and Prevention of Reperfusion Injury and in Organ Transplantation
For hearts under stress of ischemia at least two considerations are important: (a) providing energy sufficient to optimize performance, and (b) preventing free radical damage blood supply is restored.
(a) Myocardial Substrate Utilization
Resting healthy hearts rely on exogenous, blood borne free fatty acids (FFA) as their main energy source with carbohydrate (CHO) derived fuel sources comprised of glucose and lactate playing secondary roles. For instance, in a resting person FFA may provide 80% of energy, glucose 5%, and lactate 15% (Gertz et al., 1988; Wisneski et al., 1987). However, under exercise and other stresses total energy demand increases and the fuel mix changes with the contribution of FFA falling to 40%, glucose use increasing absolutely but remaining at about 5%, and lactate the remainder (55%). During rest lactate is relegated to a minor role as an energy substrate for the heart because arterial [lactate] is low (xe2x89xa61.0 mM). However, during physical exercise lactate predominates as the cardiac fuel energy source because production in working muscle and other tissues causes blood lactate concentration to rise to a level (2-20 mM) sufficient to be taken up and oxidized within the heart. As indicated in FIG. 1, exogenous lactate gains entry to cardiocytes because of cell membrane lactate transporters. Those transporters facilitate lactate flux down concentration and hydrogen ion (H+) gradients. Within cardiocytes, lactate gains entry to mitochondria via another lactate transporter pool, also along concentration and H+ gradients.
Realizing that CHO-derived energy sources increase cardiac performance, some investigators have attempted to promote cardiac energy resuscitation after ischemic attacks by providing glucose, sometimes with insulin and potassium. Currently used cardioplegic solutions containing glucose, insulin and potassium are sometimes referred to as GIK. Other investigators have attempted to provide pyruvate. However, from the physiological perspective such attempts are less than optimal, or misguided, because lactate, not glucose or pyruvate, is the major fuel for the heart under stress.
Recently, results of clinical trials (Ceremuzynski et al., 1999) have not confirmed viability of systemically administered GIK in the management of cardiac episodes. While GIK solutions do positively influence performance of stunned isolated hearts perfused and bathed in artificial solutions, unless GIK is administered into coronary arteries, significant effects on either cardiac performance or survival of ischemic episodes including MI is not to be expected (Apstein and Opie, 1999). Simply, GIK cannot be expected to have much effect because glucose never the major fuel for the heart. The obvious approach is to provide lactate in a form that can benefit cardiac metabolism.
(b) Ischemia-Reperfusion Injury
Ischemia is defined as the interruption of blood supply, hence the delivery of oxygen and nutrients to an organ and the subsequent removal of metabolic wastes. Examples of ischemic events include: (1) myocardial or cerebral infarction following obstruction of a branch of a coronary or cerebral artery, and (2) removal and storage of an organ prior to transplantation. In the case of myocardial infarction, prompt restoration of blood flow to the ischemic myocardium is a key component of the treatment. This is because mortality is directly related to infarct size which is related to the severity and duration of the ischemic event.
Despite the need to supply an organ cut-off from a normal blood supply with oxygen, it has been found that reperfusion injury may occur upon restoration of blood flow. This is because sudden return of oxygen to an oxygen-deprived tissue results from the production of reactive oxygen species (ROS), namely, hydrogen peroxide, hydroxyl radicals and superoxide radicals which are formed from both extracellular and intracellular sources (Davies et al.). ROS are highly reactive molecular species that, under normal conditions, are scavenged by endogenous defense mechanisms (Viguie et al.). However, under conditions of post-ischemic oxidative stress, ROS interaction with a variety of cellular components, causing peroxidation of lipids, denaturation of proteins, and interstitial matrix damage, resulting in increase of membrane permeability and release of tissue enzymes. In an attempt to minimize these undesirable side effects of perfusion, Simpson et al. suggest the use of an inhibitor of ROS production to protect the reperfused myocardium. Particularly, results of Simpson et al. suggest use of agents and inhibitors (e.g., allopurinol) that reduce ROS levels.
In a similar content, Brunet et al. suggest the use of acetylcysteine to reperfuse hearts. In particular, they conclude that N-acetylcysteine treatment decreases the production of ROS in reperfused rat hearts. Use of the amino acid, N-acetylcysteine is potentially efficacious in this regard as it is a precursor to the powerful cellular antioxidant glutathione (GSH).
In a further effort directed to protecting reperfused heart tissue, U.S. Pat. No. 5,075,210 herein incorporated by reference, discloses a process for reperfusing a heart for transplantation. The patent discloses a cardioplegic solution containing sodium chloride, potassium, chloride, calcium chloride, sodium bicarbonate, sodium EDTA, magnesium, chloride, sodium pyruvate and a protein.
U.S. Pat. No. 5,294,641, herein incorporated by reference, is directed to the use of pyruvate to prevent the adverse effects of ischemia. The pyruvate is administered prior to a surgical procedure to increase a patient""s cardiac output and heart stroke volume. The pyruvate is administered as a calcium or sodium salt. The pyruvate can alternatively be an ester of pyruvate acid such as ethylamino pyruvate. Pyruvate is used because it is a cellular energy source, and potentially-though not practically (vide infra), may serve as an antioxidant.
With due consideration to growing acceptance of pyruvate as an effective component of reperfusion solution, it has been recognized that traditional pharmacological pyruvate compounds, such as salts of pyruvic acid, are not particularly physiologically suitable. For example, inorganic salts of pyruvate lead to the accumulation of large concentrations of inorganic ions (e.g., potassium, calcium or sodium) in body fluids. Accordingly, while potentially suitable to organ preservation, the salt-pyruvate compounds are not ideally suited to treating an organ or supplementing energy in an active person in vivo, and it is recognized that a need exists to deliver a monocarboxylate (pyruvate-like) compound which is more physiologically appropriate
In this regard, U.S. Pat. No. 5,283,260, herein incorporated by reference, is directed to treatment of diabetes with a physiologically acceptable form of pyruvate. The patent discloses a pyruvate compound in the form of a covalently linked pyruvate-amino acid. By utilizing this type of pyruvate delivery system, the negative effects of inorganic-pyruvate salts are avoided. However, administration of large amounts of pyruvate-amino acid compounds may result in an amino acid nitrogen overload which could harm patients with liver and/or kidney pathology.
Similarly, U.S. Pat. No. 5,667,962, herein incorporated by reference, is directed to use of pyruvate thiolester for the prevention of reperfusion injury. The intention of that invention is to provide a compound comprising covalently linked pyruvate and N-acetylcysteine. However, design of the material is flawed in its purpose and mode of action.
Not withstanding use of compounds of complexes of pyruvate and antioxidant compounds in cardioplegia and organ transplantation procedures, as well as covalently linked compounds involving mixtures of pyruvate and amino acids with antioxidant characteristics such as embodied in the above identified US Patents, the emphasis on pyruvate as a monocarboxylate to deliver to stressed organs and tissues is misplaced. In fact, any attempts to utilize pyruvate as an agent to improve status of working heart and skeletal muscles results in a delayed response because lactate,. not pyruvate, is the preferred compound exchanged (xe2x80x9cshuttledxe2x80x9d) among organs, tissues, cells, and intracellular compartments. Tissue levels of lactate exceed those of pyruvate by 10 to 100-fold, and cell membrane monocarboxylate transporters are specific to lactate, not pyruvate. Beneficial effects of pyruvate administration accrue only after conversion to lactate, which is the preferred material for cell-cell exchange via the xe2x80x9cLactate Shuttle.xe2x80x9d
As stated by Sumegi et al. (p. 77) who utilized nuclear magnetic resonance spectroscopy (NMR) and [3-13C]pyruvate tracer to study pyruvate metabolism in hearts of living rats: xe2x80x9cThe infused [3-13C]pyruvate was quickly converted to [3-13C]lactate in the blood of Wistar rats.xe2x80x9d [NB, this pyruvatexe2x86x92lactate conversion is due to presence of lactate dehydrogenase (LDH), an enzyme highly abundant in erythrocytes, such that in blood the lactate/pyruvate ratio is normally 10 and can increase an orderof magnitude under physiological stress (Brooks, 1998).] Surprised by their results and unable to explain them, with some trepidation Sumegi et al. went on to state (p. 80): xe2x80x9cThese data show that the extracellular lactate is preferentially taken up by a portion of cytoplasm which converts lactate to pyruvate and transfers it to the mitochondrial reticular network.xe2x80x9d However, in making the statement concerning conversion of lactate to pyruvate in cytoplasm, Sumegi et al. recognized a major problem in interpretation of their data. By failing to recognize existence of a mitochondrial form of lactic dehydrogenase (mLDH, FIG. 1), they had to: xe2x80x9cassume that a fraction of the cytoplasm associated with the mitochondrial reticular network is specialized for converting the lactate to pyruvate, with the pyruvate being channeled to the mitochondria.xe2x80x9d [NB, in striated muscle (heart and skeletal) mitochondria do not exist as discrete organelles, but as part of a large, interconnected network, the Mitochondrial Reticulum (Kirkwood, et al.)]. As indicated by presence of mLDH (FIG. 2), the highly improbable assumption of Sumegi et al. is unnecessary, and the same physiological result is readily accomplished because of LDH.
Paradoxically, addition of exogenous lactate to the blood of mammals has alkalinizing effects because lactate removal from the blood, whether by oxidation or gluconeogenesis, requires a proton (in the ratio of 1: 1, protion:lactate anion) for transport and metabolism. Thus, by virtue of the acid/base chemistry in mammals, addition of lactate anion to plasma mitigates the presence of lactic acidosis.
A. In Proof of Cell Membrane Lactate Uptake, the Following Data from Roth and Brooks (1990a, 1990b) Are Presented
Sarcolemmal vesicles were isolated from rat skeletal muscle and effects of various monocarboxylates including L(+) and D(xe2x88x92) lactate (FIG. 2), and other monocarboxylates were determined (Roth and Brooks, 1990a, 1990b). Results indicate saturation kinetics and stereospecificity for the L(+) compared to the D(xe2x88x92) isomer of lactate.
These and other characteristics (e.g., pH dependency, temperature sensitivity and inhibition by known monocarboxylate inhibitors such as CINN, vide infra) indicate presence of a sarcolemmal lactate transport protein. Further, results indicate far greater affinity for lactate (FIG. 2), than for pyruvate (FIG. 3).
B. In Proof of Mitochondrial Lactate Uptake and Oxidation, the Following Data Are Presented (Brooks et al, 1999a).
(1) Inhibition of mitochondrial Lactate and Pyruvate Uptake and Oxidation by CINN:
Traditionally, several substrates, and combinations of substrates have been used to study mitochondrial respiration in vitro. Pyruvate-malate has usually been used to probe mitochondrial Complex 1, succinate Complex 11, and TMPD+ascorbate Complex III. In contrast, lactate or lactate-malate has been infrequently used. However, pyruvate and lactate are known to share the sarcolemmal lactate transporter(s), and pyruvate gains access to the mitochondrial matrix by means of facilitated transport. Oxidation of lactate by isolated mitochondria is permitted by the presence of a mitochondrial pool of LDH which provides matrix pyruvate from exogenous lactate. To establish that lactate gains access to the mitochondrial matrix via facilitated exchange via a monocarboxylate (MCT) transport protein, we utilized polarography and inhibition by the known MCT inhibitor xcex1-cyano -4-hydroxycinnamate (CINN). Results on rat liver mitochondria are shown in FIG. 4.
Results show CINN inhibition of pyruvate and lactate oxidation, but bypass of the CINN block by succinate, which gains access to the matrix by a different transport mechanism and which donates electrons to Complex II, in contrast to lactate and pyruvate which are NADH-linked substrates and donate electrons to Complex I. Additionally, results of experiments on rat liver mitochondria with 10 mM glutamate as substrate show no measurable effect of CINN on states 3 or 4 respiratory rate, RCR and ADP/O (data not shown). Absence of an effect of CINN on glutamate oxidation by isolated mitochondria is of value because, like pyruvate, glutamate is an NADH-linked substrate. Thus, the effect of CINN on pyruvate and lactate oxidation is upstream of Complex I.
(2): Presence ofMCT1 or a MCT1 Homologue in Mitochondria: Mitochondria were isolated from skeletal muscle, rat liver and heart by standard techniques of cell fractionation. Subsequently, skeletal muscle mitochondria were probed with a polyclonal antibody to the C-terminus of rat MCT1 (Nxe2x80x2-CPLQNSSGDPAEEESPV-Cxe2x80x2), and results of a Western blot analysis displayed in FIG. 5. The results indicate presence of a mitochondrial protein which reacts with an antibody to the C-terminus of MCT1. To exclude the possibility of contamination from sarcolemmal MCT1 in the mitochondrial preparation, mitochondrial and cell membrane fractions were probed with antibodies to MCT1 and the cell membrane Glucose Transport Protein #1 (GLUT1). Scarcely detectable levels of GLUT1 in mitochondrial indicate minimal contamination from cell membranes in the mitochondrial preparation. Thus, it is evident that rat striated muscle mitochondria contain a monocarboxylate transporter with high homology to MCT1. Further, similar results have been obtained on human skeletal muscle and muscle mitochondria (Dubouchaud et al.).
(3): Presence of Lactic Mitochondrial Dehydrogeniase (mLDH): Mitochondria were isolated from rat liver and heart by standard techniques of cell fractionation. Subsequently, mitochondria were treated by gel electrophoresis and the results displayed in FIG. 6. The results indicate presence of mitochondrial LDH, which is mainly of the H4 isoenzyme in heart and red skeletal muscle (not shown). In contrast, liver mitochondria contain only the LDH5 isoform, whereas both LDH4 and LDH5 are present in cytosol of rat liver. These results support the conclusion of separate cytosolic and mitochondrial pools of LDH in rat muscle, liver and heart. Again, the presence of LDH in human muscle mitochondria has been demonstrated (Dubouchaud et al.)
Accordingly, it is desirable to have an alternative physiologically compatible therapeutic compound based on lactate, not pyruvate for lactate is the monocarboxylate selected by nature for exchange in the blood and between and among cells, tissues, organs and intracellular compartments. Again, pyruvate added to the circulation will need to be converted to lactate prior to entry into cells. The sites of this conversion will be erythrocytes or cytosol of cardiac and skeletal muscle cells. Therefore, provision of pyruvate will only slow delivery of monocarboxylate material for mitochondrial oxidation.
(2) Use of Lactate Thiolester as an Energy Source Supplement During Exercise and Recovery
Recent advances in basic biochemistry and exercise physiology have shown that the formation and removal of lactic acid is an integral part of both digestive and metabolic processes. Further, as lactate is a fuel for the heart (vide supra), lactate is also a major energy source in working skeletal muscle.
According to the xe2x80x98Glucose Paradoxxe2x80x99 hypothesis (reviewed by Foster, 1984, also see Newgard et al., 1983), dietary carbohydrate courses an indirect route before becoming liver glycogen. It is known that dietary carbohydrate is digested and then enters the portal circulation (i.e., that vein between the small intestine and the liver) largely as glucose.
In contrast to traditional theories which hold that the liver extracts large amounts of portal blood glucose for synthesis of glycogen, it is now believed that portal glucose bypasses the liver and enters the systemic circulation through the hepatic vein. Much of this glucose then reaches the resting musculature, where it is either stored as glycogen or converted to lactic acid. This lactic acid then either diffuses or is transported from the sites of production and reaches the systemic circulation. Much of the circulating lactic acid is removed by the liver.
In the glycogen-depleted liver, lactic-acid becomes the preferred precursor material from which to synthesize glycogen. Because glycogen is paradoxically synthesized by a rather circuitous pathway, the process is alternatively termed the Glucose Paradox, or the Indirect Glucose to Liver Glycogen Pathway.
According to the xe2x80x9cLactate Shuttlexe2x80x9d hypothesis (Brooks, 1985, 1986a, 1986b), 1987, 1998, 1999a, 1999b); lactic acid is an important fuel source for exercise as well as resting and exercise-recovery conditions (FIG. 7). During exercise, active fast-twitch muscles produce lactic acid, which is then available as a fuel for slow-twitch, highly oxidative skeletal muscle fibers (Donovan and Brooks, 1983). This process appears to operate all the time as demonstrated in human subjects exercising at sea level (Bergman et al 1999; Mazzeo et al. 1986; Stanley et al. 1985, 1986, 1988), or high altitude (Brooks et al., 1991, 1992). In fact, based on conclusions conducted on rats (Brooks and Donovan, 1983; Donovan and Brooks, 1983) and humans (Bergman et al., 1999;, Brooks, 1992;, Stanley et al., 1988), lactate appears to be a more important fuel for muscular exercise than does glucose, especially during sustained exercise and recovery from sustained, exhausting exercise (FIG. 8).
Results of studies conducted by Gladden and associates (1991, 1994) on canine muscles made to contract in situ support observations made on human subjects. The data clearly show that working canine muscles consume and utilize lactate in a concentration-dependent manner.
Beyond the work of Brooks and associates whose studies have focused on exercising rats and humans, data of Richter et al. (1988) also show that working human skeletal muscle can consume and utilize blood lactate in a concentration-dependent manner. Further, their results show that when a muscle takes up lactate, it decreases its use of glucose.
The oxidation of lactic acid during exercise can be appreciated on both relative and absolute bases. Of the lactic acid produced and removed during exercise, approximately 75% is removed by oxidation and 20 % is converted to glucose (Bergman et al. 1999; Donovan, C. M. and G. A. Brooks, 1983; Stanley et al., 1988, Brooks et al, 1991b, 1992). Of this latter portion, most will ultimately be oxidized also (Brooks, and Donovan, 1983, Brooks et al. 1992). Quantitatively, lactic acid oxidation exceeds glucose oxidation during exercise with 10-25% of the total energy supplied derived from lactic acid oxidation. These findings suggest that it may be desirable to employ lactic acid as a supplement during and/or after exercise.
However, the use of lactic acid as a fuel in the body carries with it potential penalties. Lactic acid accumulation in the muscle is painful and interferes with contraction processes. Further, large amounts of lactic acid in the blood cause pH to fall which is physically and psychologically distressing to the performer. These disadvantages are associated with the hydrogen ion (H+, or proton) which results when lactic acid dissociates in aqueous solutions. For these reasons lactic acid accumulation has long been suspected as a cause of muscle fatigue (Brooks et al., Exercise Physiology: Human Bioenergetics and its Applications, Chapter 33, Mayfield, Mountainview, Third Edition, 2000).
Therefore, it may be advantageous to provide a carbohydrate derived fuel source to an individual engaged in prolonged, strenuous exercise, and it would be more efficacious to provide the carbohydrate energy in the form of a xe2x80x98lactic acid-likexe2x80x99 substance which would provide a more immediate fuel source.
Thus, on the bases of both the xe2x80x9cGlucose Paradoxxe2x80x9d and xe2x80x98Lactate Shuttlexe2x80x99 concepts, providing a xe2x80x98lactic acid-likexe2x80x99 material to athletes during exercise and recovery from exercise would also augment the beneficial effects of providing dietary glucose.
In addition to an energy deficit, sustained exercise also results in dehydration and loss of electrolytes (Brooks et al., 1996). Studies of gastrointestinal absorption have shown that dilute (2-8%) solutions of carbohydrate-electrolyte solutions do not hinder, but may promote gastric and intestinal emptying. Thus, a side benefit of supplying energy in the form of a lactate-containing compound is the ability to provide minor amounts of inorganic lactate salts in solution (e.g., sodium, potassium, magnesium, and calcium). In contrast to sarcolemmal transport which is hydrogen ion (H+)-mediated, intestinal lactate (and glucose) is sodium (Na+)-mediated. Thus, inclusion of 0.2% Na+-lactate with 2% LNACE, and 2-4% other simple sugars and multi-dextrans, would yield a solution that readily promotes fluid, electrolyte, and energy balance and restoration in athletes and other active persons. Similarly, such a beverage would represent an ideal means to treat diarrhea in infants and others.
As already indicated, reactive oxygen species (ROS) can be generated when ischemic tissues are reperfused. Not withstanding the involvement of ROS in reperfusion injury, during sustained, high-intensity exercise when the rate of oxygen consumption is high and sustained, the potential for ROS generation is significant (Davies et al., Viguie et al.). Thus, physical exercise carries with it potential for damage to muscle, heart and blood cells.
Accordingly, it is desirable to produce an energy supplement for exercising individuals based on lactate and the ROS trapping amino acid, N-acetylcysteine. Further, it is desirable to produce an energy-yielding supplement that will facilitate hydration and electrolyte balance in individuals engaged in, or recovering from sustained exercise.
In accordance with the present invention, in addition to providing an antioxidant thiolester for cardiac resuscitation and prevention of reperfusion injury, LNACE is presented as a novel method and composition beneficial to a mammal""s fluid, electrolyte and carbohydrate balance during exercise and subsequent recovery are provided.
In one aspect, the invention provides a method of supplying nutritional supplementation to humans and other mammals by means of an aqueous solution of at least one lactic acid salt. This solution is administered in oral dosage form to the host in an amount sufficient to affect the mammal""s fluid, electrolyte or carbohydrate balance during exercise and/or subsequent recovery.
In another aspect, a nutritional supplement is provided comprising an aqueous solution of at least one lactic acid salt in an amount sufficient to affect a mammal""s fluid, electrolyte or carbohydrate balance during exercise and/or subsequent recovery.
In other aspects, the present nutritional supplement includes mixtures of organic and inorganic lactic acid salts, lactate polymers, and/or simple complex carbohydrates. Such mixtures containing fructose, glucose polymers and larger polysaccharides for provision of fuel energy via enteral (oral) administration rep[resent a different adaptation of the composition than for cardioplegic administration into the blood.
Accordingly, the global objective of this invention to provide a new and improved lactate compound.
Specific objectives of this invention are:
(1) to provide a new and improved method to provide energy to the stressed heart,
(2) to provide a new and improved method to protect cells, tissues, organs and intact individuals from reactive oxygen species (ROS), from reperfusion injury following ischemia, and
(3) to provide a new and improved method to supply supplemental energy to exercising individuals.
To achieve the foregoing objects and in accordance with the purpose of the invention, as embodied and broadly described herein, the novel lactate compound of this invention comprise a lactate thiolester. Preferably, the thiol is cysteine or methionine. In a particularly preferred form, the compound is a N-acetyl ethyl ester of the cysteine or methionine amino acids.
The general form of the compound is:
where R is selected from ethyl, methyl, and alkyl groups. For example the compound could include a ethyl group as shown.
The invention is directed to use of the novel lactate compound for oral consumption or for reperfusion of tissue and organs both in vivo and in storage. Accordingly, the invention includes methods for providing fluid, energy and electrolytes to physically active persons or those exposed to hot, and hot-humid environments, as well as for the preservation of tissue deprived to oxygen through events including, but not limited to, coronary infarction, stroke, mesenteric infarction, organ transplant (during preservation and intravenously after grafting to the organ), including amputated limbs. The compound is also believed well suited to treatment of acetaminophen poisoning to the liver that depletes liver glutathione stores leading to acute hepatic necrosis.
It is believed that lactate provides a ready source for cellular mitochondrial oxidation and that the thiol group from cysteine scavenges ROS as well as provide a precursor for GSH synthesis. Accordingly, the subject novel compound provides a stable, and physiological compound with the beneficial result of delivering lactate and a thiol.

Lactate thiolester for cardiac energy resuscitation and prevention of reperfusion injury and use as an energy supplement during exercise and recovery

Abstract: Further, the invention involves use of mixtures of lactate- and pyruvate compounds as well as hexoses (glucose and fructose), maltodextrins and electrolytes as adjutants to support LNACE in its specific purposes.


In a microbubble liquid producing apparatus, an air bubble liquid producing device for mixing liquid with air by an aspirating pressure generated by a pressure pump arranged on a liquid feeding pipeline while aspirating the liquid from a liquid supply source and forcibly feeding the liquid by pressure is disposed on the liquid feeding pipeline on the upstream side of the pressure pump relative to the liquid feeding direction. A first air-bubble atomizer is disposed on the liquid feeding pipeline on the downstream side of the air bubble liquid producing device for atomizing the air bubbles contained in the air-mixed liquid produced by the air bubble liquid producing device. A second air-bubble atomizer is disposed on the liquid feeding pipeline on the downstream side of the first air-bubble atomizer for further atomizing the air bubbles atomized by the first air-bubble atomizer.

A conventional microbubble-liquid producing apparatus of this type is disclosed in, for instance, Japanese Published Unexamined Application No. 2003-117365(A). The conventional microbubble-liquid producing apparatus comprises an air-liquid mixing pump for aspirating mixture fluid of liquid and air, a resistor for imposing resistance to fluid discharged from the air-liquid mixing pump, and an inverter for controlling the rotation speed of the air-liquid mixing pump, wherein an annular fluid passage having a narrow radial width is formed in a casing of the air-liquid mixing pump and many stirring blades protruding into the fluid passage are formed on the periphery of a bladed wheel.    [Patent Literature 1] Japanese Published Unexamined Application No. 2003-117365However, the aforementioned conventional microbubble-liquid producing apparatus is designed to produce desired air microbubbles at a given time by using the single air-liquid mixing pump. For that purpose, the conventional apparatus has a need to assume its complicated structure comprising the annular fluid passage having the narrow radial width inside the casing and a number of stirring blades protruding into the fluid passage on the periphery of a bladed wheel.
Furthermore, the conventional apparatus requires the inverter for accurately controlling the rotation speed of the air-liquid mixing pump, inevitably to increase its production cost. Besides, in order to perform maintenance and inspection on the air-liquid mixing pump and other components, the complicated and specific structure of the apparatus should be totally known, but at any rate, the maintenance and inspection cannot be performed easily.
The present invention seeks to provide an apparatus for producing microbubble liquid, having a simplified structure to be produced at a moderate price and capable of being maintained and inspected with ease, and further having an advantage of capable of effectively producing microbubble liquid containing fully microscopic air bubbles, and further provide a device for atomizing air bubbles using the aforementioned apparatus.

Apparatus for producing microbubble liquid and device for atomizing air bubbles using the same


A method of forming a backpack with an integral gun scabbard has been devised whereby the user has a convenient place for the storage and carriage of a rifle, shotgun, or other long gun type of firearm, and simultaneously can store and carry a variety of other sundry cargo while moving about. The backpack is devised in such a way as to permit easy and rapid access to and retrieval of said firearm from the storage. It is equipped with dual padded shoulder straps. In an ideal embodiment, a waist belt is included to facilitate the stabilization of the scabbard when the firearm is being withdrawn, as well as to contribute to the load bearing functions of the backpack.

Not Applicable
Not Applicable
Not Applicable
The invention relates to backpacks. In particular, the present invention relates to a backpack which is designed to have the dual utility of carrying a long barreled firearm as well as a load of varied cargo, and furthermore allows rapid access to and use of said firearm without removal of the backpack from the user""s back. This combined capability is most useful for the activity of hunting, wherein a user will often be carrying some sort of backpack filled with the sundries necessary to the outing, and simultaneously carrying a long gun type of firearm. These latter are often fitted with a single strap or sling, which permit them to be slung over a user""s shoulder in order to relieve the user""s hands of a constant burden. It can readily be imagined that the shoulder straps and bulk of a backpack generally cause direct interference with the carriage of a long gun over one""s shoulder. There have been some attempts to address this problem, with varying degrees of success. A common handicap in the prior art is that the mechanisms devised for attaching a firearm to a backpack generally require the removal of the backpack from the wearer""s back in order to detach the firearm from its carriage. In hunting, it is frequently necessary to have quick and ready access to one""s firearm, and products in the prior art do not facilitate this.
It is further presented that for purposes of safety as well as for the purpose of the protection of valuable firearms while actively hiking while hunting, it is necessary and beneficial to have the firearm enveloped in some type of protective surround whereby passing branches won""t protrude into the firing mechanism of the firearm, and also won""t be permitted to scratch and mar the finish of the gunstock, which is frequently made of wood.
Another obstacle in the art is that most rifles, shotguns, and other long gun firearms are of sufficient length that they are generally an encumbrance to activity regardless of where they are stowed. If they are attached to a backpack, they often will stick up too high and thereby snag overhead branches as the wearer passes under. If they are too low, they tend to bump and collide with the user""s legs, or to hit logs, rocks, and the like that the user is stepping over.
There is a long history and variety of backpacks and related devices for carriage of loads upon the human back, and the prior art is widely explored, known, and developed. Their size and dimension ranges from a small, compact variety known as daypacks, such as disclosed in U.S. Pat. No. 5,573,166 to Leja, to larger packs designed for carrying heavier and more bulky loads such as disclosed in U.S. Pat. No. 6,179,188 to Gleason. Any and all of these will cause the aforementioned interference with the carriage of a long gun.
There is similarly a long and varied history of means and mechanisms for carriage of long guns, some of which include some type of backpack-based storage. Most often, a variety of straps are used to attach a gun either to a simple platform as disclosed in U.S. Pat. No. D311,813 to Oliver, U.S. Pat. No. 4,754,904 to Fischer, et al., or similar strap combinations might be used to attach a firearm to a backpack. These varieties typically require the manipulation of a number of straps both to attach and to remove the firearm from the carriage, thus being examples of devices that are not well suited to the active pursuit of game. Similar devices are disclosed in U.S. Pat. No. 5,664,721 to Homeyer, and U.S. Pat. No. 5,669,170 to Norris.
Other devices have been developed which attempt to maintain the firearm in a ready position while relieving one""s hands of the constant burden of carriage, as for example disclosed in U.S. Pat. No. 6,152,338 to Smith, wherein straps and a spatula type of structure are used to support a firearm in a carriage position forward of the user""s shoulders. While this device may serve to function in combination with a backpack and does place the firearm in a position of ready access, it does not provide a protective surround for the firearm. Further, if while using a device of this variety a user came across game, he would still have to unfasten one or more straps in order to have free use of his firearm. In addition, it may be felt that having the firearm positioned forward of the shoulder places it in a position of obstruction and causes interference with one""s activities.
Examples in the prior art which attempt to address carriage of a long gun in a manner that either protects it or positions it out of a user""s way generally do not permit the simultaneous carriage of a backpack or load other than the firearm. For instance, as disclosed in U.S. Pat. No. 5,016,793 to Derkatz, the firearm is to be housed in a standard scabbard, which has been fitted with shoulder straps for carriage. In this case, there is no provision for carriage of an additional load, such as a hunter would typically need in a day""s outing, nor is the described harness sufficient to comfortably carry significant cargo. The device as disclosed could not be fitted with significant cargo carrying capacity, and further would preclude the carriage of a backpack or waist pack. Another example is disclosed in U.S. Pat. No. 5,806,742 to Mott, et al., wherein a described gun case is fitted with backpack style shoulder straps. While this device is suitable for the transportation of a firearm, it would not be suitable for active hunting, as the case is designed to be of flexible construction, which causes it not to function as a scabbard, since the flexible cloth will act as an impediment to the rapid withdrawal of the firearm. In addition, it is fitted with a cover flap and closure strap, which obviate that it is not designed for the rapid removal of the contents. Further, this device is designed without the intent of bearing a load greater than the firearm and some small associated items such as ammunition, does not provide for the storage capacity of any type of backpack, and precludes the simultaneous use of a separate backpack.
There are examples of backpacks that have been designed to carry a combination of sundries and some sort of bulky elongated article, such as disclosed in U.S. Pat. No. 4,693,402 to Comeau and U.S. Pat. No. 6,367,674 to Tabor. These are generally light duty and are not designed or apparently envisioned with the mechanical and physical attributes necessary for the carriage of a long gun type of firearm.
It can readily be appreciated that in the sport of hunting, participants frequently range far afield on foot, and often desire to carry in a backpack a range of goods necessary to the outing. These can include camping gear, survival equipment, inclement weather gear, water, and food stocks, as well as the sundries devoted to the sport of hunting. This gear and these packs can be quite bulky, and as previously shown can interfere with the traditional over-the-shoulder sling carriage of a long gun. It can further be imagined that when climbing hills, passing through thick brush, and the like, the use of both hands is desirable, and that for reasons of safety, convenience, and the relief of fatigue, it is desirable to stow one""s firearm in a place that keeps it safe and out of the way, but still maintains it in a ready position in the event that one has an unexpected encounter with game.
It is submitted that the present invention substantially meets these needs, and is a new, original, and unique departure from the prior art, and that it will be embraced with enthusiasm by those avid participants in the sport of hunting who prefer to hike about on their feet.
The present invention is a backpack which is capable of simultaneously carrying a load of miscellaneous cargo and a long gun type of firearm. A primary object of the invention is to present a backpack of true dual utility, which will be capable of carrying significant loads of cargo and which provides a solution to the problem of where to stow a long gun on one""s person while one is carrying a backpack. More specifically, a backpack is presented which has two shoulder straps, which extend from the top of the pack forward over the shoulders of a user, and then return on either side of the waist to reattach at the lower part of the backpack. In the preferred embodiment, these straps are padded on their upper portion in order to make the pack more comfortable for the wearer, and are fitted with a means of making them adjustable in length. Also in the preferred embodiment, a waist belt is included for the dual purposes of adding to the load bearing capabilities of the backpack, and to stabilize the lower portion of the pack in order to facilitate the rapid withdrawal of the firearm from its housing. Preferably, this waist belt is of heavy-duty construction, is padded for comfort, is wide nearest the main panel of the backpack, and tapers in a symmetrical fashion as it develops forward toward an adjustable and releasable closure. The backpack is sized in such a manner that the whole of the primary structure, which uses a generally rectangular panel as its foundation, fits most users in a way that its bottom extent ends just above the buttocks, and the top rises to the level of the top of the user""s shoulders. This latter dimension is important because it permits the user to reach over his shoulder, and to grasp and withdraw the firearm from its housing, without removing the backpack.
The storage compartments of the backpack are of two diverse types. Firstly, a scabbard is provided, which in the ideal embodiment is of semi-rigid construction to facilitate easily inserting and rapidly removing a firearm, and is a long, tapered, hollow sheath with an open top which is sized such that it fits most long gun type firearms, including scoped rifles and shotguns. One of the objects of the invention is to present a device which allows the rapid and ready retrieval of one""s long gun from its storage in the event it is needed. To accomplish this, the top of the scabbard is approximately flush with the top of the main panel of the backpack, which is in turn approximately level with the top of the wearer""s shoulders, thereby permitting the user to easily reach over his shoulder and grasp the butt stock or the pistol grip of the firearm for its withdrawal. It is likewise important that the scabbard be positioned with a minimum of space between it and the user""s back, so that one doesn""t have to reach overly far back to grasp the firearm. Of final importance in sizing the scabbard is to make it sufficient of length to house a standard long gun""s barrel, sights, action, trigger assembly, and fore-stock up to the approximate position of its pistol grip, but it must not be made of such a great length that it protrudes overly far below the bottom level of the backpack in order that it not become an encumbrance to activity. In the preferred embodiment, this scabbard is fixedly attached, plan form, to the main panel of the backpack. It is oriented vertically, with the top approximately even with the top of the main panel and the bottom protruding below the bottom extent of the main panel, and fills approximately half of the lateral space of the front side of the main panel.
The second type of storage compartment is comprised of a six sided, box type construction, is made of fabric, and has an orifice with a zipper, clasp, or like closure, and is similar to conventional cargo compartments on backpacks of the prior art. In the present embodiment, a cargo compartment is fixedly attached to the front side of the main panel of the backpack, adjacent to the scabbard, and filling the remaining lateral space. In a preferred embodiment, it is of a similar thickness to the scabbard, thereby filling approximately the same volume of space above the main panel of the backpack. By constructing both the scabbard and first cargo compartment of the same thickness, a uniform layer in the backpack is formed which facilitates placing a uniformly dimensioned larger cargo compartment outside these first storage units. This larger compartment is also a six sided, sewn fabric, box type construction, with an orifice and a releasable closure therefore. In an alternative embodiment, the first storage compartment can be made of a greater depth than the scabbard, thereby giving it substantial storage volume, and the larger overlaid compartment can be foregone. It can readily be seen that all of these described standard cargo compartments may be further internally subdivided, with provision made for individual access to, and selective closure for, each of the storage cells thereby formed, without substantially altering the intent or scope of the invention. It can similarly be seen that the size and orientation of the cargo compartments can be varied and altered in the manner common to load bearing backpacks in the prior art, without substantially altering the intent or scope of the invention.
The advantages of this invention over the prior art arise from the fact that this backpack is intended to be of full and simultaneous use both as a cargo carrying backpack, and as a device for safely, efficiently, comfortably, and conveniently carrying a long gun. Furthermore, it is intended to be of use to one who is actively engaged in hiking while hunting, thereby leaving both hands, at least one of which would otherwise be holding or stabilizing a gun, free to assist in balance, climbing, holding away branches, and the like. The present invention offers the further advantage of providing easy and rapid access to the user""s firearm. When it is necessary, there is minimum delay in having the gun unsheathed and moved to a firing position. Furthermore this action can be accomplished without removing the backpack from one""s back. Lastly, by enclosing the majority of the firearm in a protective envelope and housing it aft of one""s shoulders, there will be improvements in the protection of the firearm, and safety advantages in having the trigger, gun safety, and firing mechanism enclosed while one is traveling through and about protruding branches and the like.
It is presented that one reason that examples similar to this invention are not found in the prior art is because the mechanical and physical proportions of the present invention are not obvious. The present invention offers a dual utility backpack, which serves all of the functions of a standard backpack and has the added benefits and conveniences resulting from the careful incorporation of a gun scabbard. It can be seen that the present invention is an entirely unique, new, and useful departure from all that has been accomplished in the prior art.


The wiring case has a detachable display device for displaying contents of data and electric transmission/reception communications established with a predetermined controlling device. In the display device, a pair of wiring members are prepared. The tip end portions of the wiring members are directed towards the bottom surface portion of the wiring case, and the each tip end portion has a contact point. The wiring case has an opening at a section opposing to the bottom surface portion, and a stopper portion is formed at end portion of each of sidewalls of the long-scale box.

This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2000-206820, filed Jul. 7, 2000, the entire contents of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to a wiring case for housing a plurality of receiving devices (devices to be controlled) such that each of which can establish data and electric communications with a transmitter device (control device) via two power lines.
2. Description of the Related Art
Conventionally, a two-wire type data and electric transmission/reception communication system is known as a technique for carrying out data and electric transmission/reception communication which is conducted with use of two power lines (that is, a technique for carrying out transmission/reception of power (electricity) and data communication at the same time) (cf. Japanese Patent No. 27887976). In this system, one transmitter-side device and a plurality of receiver-side devices are connected together via two power lines. While a power which contains data component is transmitted from the electric transmitter device, the electrical charge and data decoding are carried out on the side of a receiver device. When the electrical transmission is stopped in the transmitter side, the receiver device a power containing data addressed to the transmitter device is sent on the basis of the charged power. In this manner, the transmission/reception communication of electrical power and data can be carried out between one and n-number devices with a less amount of wiring.
In some cases of the actual application of such a two-wire data and electric transmission/reception communication system, the number of receiver devices becomes 20 to 30 or even more, or the site where a receiver device is mounted must be charged from one place to another frequently. Under these circumstances, it is very important to carry out the wiring operation for connecting the transmitter device and the receiver devices with each other at high efficiency. In view of increasing the efficiency of the wiring operation, it is effective to use a wiring duct base as discussed in Japanese Patent Application KOKAI Publication No. Hei10-177353.
Such a wiring duct base has a substrate portion and engagement portions formed along both sides of the substrate, and has a flat-plate shape in which at least two tape-like conductive members for transmitting electrical signals are provided on the surface of the substrate along its longitudinal direction. A receiver device is formed into a unit (display unit), and a conductive member electrically connected to the receiver device is provided on the rear surface side of the unit, with stopper portions being formed at both end sides. As the stopper portions engage with the engagement portions of the wiring duct base, the display unit is mounted on the front surface of the wiring duct base. As it is mounted, the conductive member located at the rear surface section of the display unit is brought into contact with the tape-like conductive member to be electrically connected thereto. The strength of the engagement of the stopper portions and engagement portions between the display unit and the wiring duct base is set such that the strength on one end is looser than that of the other end, and the display unit is detached from the wiring duct base from the looser engagement end.
With the wiring duct base having the above-described structure, the display unit can be mounted at an arbitrary position. Further, since the wiring has been provided in advance, a further wiring operation is not required when replacing the unit.
In the two-wire data and electric transmission/reception communication, generally, a large-capacity power is allowed to flow in a conductive member. Therefore, a pair of conductive members must be kept away from each other by a certain distance or more so that mutual interference, that is, one conductive member being interfered with the power of the other one, can be avoided. Further, the conductivity of each conductive plate is determined by a product of its cross sectional area and surface dimension (cross sectional area x surface dimension), and therefore when the conductivity is lowered, the decrease in voltage is lessened accordingly.
However, the conventional wiring duct base has engagement portions formed at both ends, and therefore there is a certain limit to the area in which conductive plates can be installed. In the case where it is possible to assure a sufficient width of a section where a wiring unit is mounted (that is, the width of the wiring unit), there will be no problem since the width of the wiring unit can be increased. However, in the case where it is not possible, the cross sectional area and surface dimension of each conductive plate cannot be increased, and therefore it becomes difficult to mount such a great number of display units.
Further, the conventional wiring duct base has engagement portions on its both sides, and the display unit has stopper portions. With this structure, it requires a great force to detach a display unit from the wiring duct base, which results in a poor operability in replacement of the unit.
The present invention has been proposed to solve the above-described drawback of the conventional technique, and its object is to provide a wiring case having an excellent operability, which can assure a sufficient size of conducting members and an interval between conductive members.
According to a first aspect of the present invention, there is provided a two-wire type wiring case for mounting a device to be controlled, which establishes data and electric transmission/reception communication with a predetermined controller, the device having a front surface portion provided thereon with an electronic circuit operable by the data and electric transmission/reception communication, side portions provided thereon with respective elastic engagement mechanisms, and a rear surface provided thereon with a pair of projecting portions each having at a tip end thereof a first conductivity member electrically connected to the electronic circuit, the wiring case comprising: a long-scale mount portion for detachably mounting the device, the long-scale mount portion comprising: a pair of second conductivity members provided in a band-like arrangement in a longitudinal direction at positions which are respectively contactable with the pair of first conductivity members, the pair of second conductivity members having a gap provided therebetween for avoiding an interference of one of the second conductivity members, the interference being otherwise caused due to power flowing through the other of the second conductivity members when the pair of second conductivity members are energized; and fixation mechanisms provided at positions remote from the pair of second conductivity members, for detachably fixing the device, by engaging with the respective elastic engagement mechanisms, wherein the pair of first conductivity members are brought into contact with the second conductivity members respectively when the device is mounted onto the wiring case so that data and electric transmission/reception communication between the mounted device and the controller is established when the second conductivity members are electrically connected to the controller.
As described, the fixation mechanisms of the long-scale mount portion are formed at side end portions thereof so that they are located as far away as possible from the second conductivity members. With this structure, the width of each second conductivity member and the distance between second conductivity members (conductive plates) can be widened as compared to the case the fixation mechanisms are formed near the second conductivity members. As the width of each second conductivity member can be increased, the conductivity of the second conductivity member is increased, thus making it possible to suppress the drop of voltage. In this manner, it is possible to increase the number of devices, which can be installed.
It may be arranged that the long-scale mount portion has a shape of substantially U in a cross section perpendicular to the longitudinal direction, and the pair of second conductivity members are provided on an inner bottom surface of the long-scale mount portion.
With this structure, the area of the bottom surface portion, which is defined by one end in the longitudinal direction and the other side, can be used for the installation of the second conductivity members. Therefore, it is possible to increase the number of devices, which can be installed.
It may be arranged that the front surface portion of the device, has a display portion, and the wiring case further comprises an outer wall portion used for fixing the long-scale mount portion to a desired position, and when the device is mounted to the long-scale mount portion, a plane including the display portion of the device and a plane including the outer wall portion make a predetermined inclining angle.
With this structure, it is possible to set the display portion of the device inclined at a desired angle with respect to the outer wall portion of the long-scale mount portion when the device is mounted on the wiring case.
It may be arranged that the front surface portion of the device, has a display portion, and the wiring case has first and second outer wall portions used for fixing the long-scale mount portion to a desired position, and when the device is mounted to the long-scale mount portion, a plane including the display portion of the device, a first plane including the first outer wall portion and a second plane including the second outer wall portion make predetermined inclining angles with respect to each other, and the first plane and the second plane cross with each other on a rear surface side of the mounted device. In this two-wire type wiring case, it may be arranged that the first plane and the second plane cross with each other at right angles.
With this structure, the first outer wall portion and second outer wall portion are fixed to tightly fit the corner portion of the wall where the wiring case is mounted, and thus the wiring case can be mounted to tightly fit with the corner portion. In most of the cases, the corner portion is made at right angles, the first plane and second plane are made orthogonal in a preferable situation.
It may be arranged that the long-scale mount portion has a bent portion for creating a gap between the pair of second conductivity members, and a part of a plane of the bent portion is made in parallel with the first plane.
With this structure, the amount of material used to prepare the long-scale mount portion, can be reduced as compared to the case where the gap is entirely filled with the material which constitutes the long-scale mount portion. Further, when the elasticity of the material is set to an appropriate value, this bent portion becomes to serve as a kind of a spring, thereby making it possible to achieve a cushion-like effect in the wiring case itself while maintaining a sufficient rigidity required as a wiring case.
It may be arranged that the elastic engagement mechanisms are engaged with the fixation mechanisms, when a body of the device is pressed towards the long-scale mount portion, and disengaged from the fixation mechanisms when both side end portions of the device are held by hand so as to deform the device as a whole towards a central line along the longitudinal direction.
With this structure, when the device is held, the engagement mechanisms are released from the fixation mechanisms, thus making it possible to attach or detach the device very easily.