bluuebunny/crossref_metadata_2025 huggingface dataset:
Eating attitudes and depression in a Turkish sample
Authors: Büyükgöze‐Kavas Ayşenur
Published: December 2006

Objective

The aim of the current study was to investigate (a) the relationship between eating attitudes and depression and (b) the differences between male and female university students eating attitudes and depression. The participants of the study included 127 female and 142 male Turkish university students.

Method

Data on depression and eating attitudes of students were collected by using the Turkish version of Beck Depression Inventory (BDI) and Eating Attitudes Test (EAT).

Results

Significant correlation coefficients were found between depression and eating attitudes scores of the students. The results indicated that there was a significant difference between eating attitudes scores of females and males. However, findings also revealed that gender did not lead to any significant difference in the depression levels of university students. With regard to the MANOVA no significant association emerged between eating attitudes and depression as a function of gender and age. Results of the study were discussed in the light of cultural context. Copyright © 2006 John Wiley & Sons, Ltd and Eating Disorders Association.
TUBELESS GASTRIC ANALYSIS AS A TOOL TO MEASURE GASTRIC SECRETORY ACTIVITY*
Authors: Segal Harry L.
Published: December 2006

This report discusses the tubeless techniques available to evaluate the capability of the gastric mucosa to secrete acid, pepsinogens, and intrinsic factor. The presence of gastric acid can be determined by proper application of the azure A ion‐exchange resin technique. Pepsinogen and intrinsic factor activity may be inferred from measurement of the urinary pepsinogens and the absorption of an oral dose of radioactive vitamin B12 with or without added intrinsic factor, respectively. A normal serum vitamin B12 level may be present in a patient with a recent failure of intrinsic factor secretion: however, a decreased level is suggestive of the absence of intrinsic factor in individuals who have no evidence for malabsorption. The value of the rapid charcoal method developed in Herbert's laboratory for measuring serum vitamin B12 is discussed.

The results of the tubeless tests have clinical significance in the diagnosis of gastritis and vitamin B12 deficiency, in the management of a patient with a gastric ulcer niche, and in suggesting further studies for early detection of gastric malignancy.
REGULATION OF INTERSTITIAL FLUID VOLUME AND PRESSURE*
Authors: Guyton Arthur C. , Coleman Thomas G.
Published: December 2006

Three recent discoveries in the field of interstitial fluid dynamics make it pos‐ sible to construct a relatively complete analysis of the regulation of interstitial fluid volume and interstitial pressure. These three discoveries are the following: First, the normal interstitial fluid pressure is about ‐7 mm Hg in contrast to the previously believed values of + 1 to +8 mm Hg. Second, the volume‐pressure curve of the interstitial spaces is very nonlinear: a very slight increase in interstitial fluid volume above normal will increase the interstitial fluid pressure from ‐7 mm Hg up to equal atmospheric pressure (0 mm Hg), but, once the interstitial fluid pressure has risen above this level, the tissue spaces balloon outward rapidly, in such a way that tremendous volumes of fluid can then be accommodated in the tissue spaces with almost no further rise in interstitial fluid pressure. Indeed, at positive pressures of +2 to +5 mm Hg, 4+ edema occurs in the S.C. tissues of the body. Third, the fluids normally present in the interstitial spaces appear not to be motile but instead bound and held firmly in place. This fluid can diffuse back and forth between the circulation and interstitial spaces because of the tremendous pressures (up to one million mm Hg) that exist for causing the process of diffusion to occur. On the other hand, this fluid cannot be removed from the tissue spaces by the usual, comparatively weak hydrostatic forces that develop in the lymphatic system or that develop as a result of osmosis at the capillary membrane. When edema occurs, essentially all the extra fluid that appears in the tissues is in the motile state and can be moved easily from one part of the tissue to another with only 0 to 5 mm Hg pressure gradient. Under normal conditions, two different factors, (a) lymphatic flow caused by arterial pulsation and other types of motion in the tissues, and (b) osmosis of fluid from the tissue spaces through the capillary membrane, keep the tissues “dry” of motile fluid and thereby maintain a negative interstitial fluid pressure of about ‐7 mm Hg. Therefore, the normal interstitial fluid volume is regulated to essentially zero motile fluid in the interstitid spaces, and the fluid that is present in the interstitial spaces appears to be only that amount entrapped by the gel in the ground substance of the tissue spaces or held by capillarity in very minute tissue spaces.
RESPIRATORY TRACT DAMAGE IN BURNS: PATHOPHYSIOLOGY AND THERAPY*
Authors: Zikria Bashir A. , Sturner William Q. , Astarjian Nubar K. , Fox Charles L. , Ferrer Jose M.
Published: December 2006

(1) Of the 27 burn fatalities with respiratory tract involvement, this internal damage was the primary cause of death in 20 cases.

(2) The edema and sodium contents in the lungs become maximal in 12 to 48 hr following the burn.

(3) The surface tension in the lungs is abnormally elevated in respiratory burns and may be one of the causes of nonobstructive atelectasis.

(4) The venous clotting time becomes depressed in the acute phase of respiratory burn and returns to normal in 24 hr.

(5) Lymph drainage into the left thoracic duct vestibule decreases during the acute phase of the burn in the dog.

(6) In the acute phase of the burn, the respiratory insufficiency is secondary to edema and to patchy atelectasis which can be reduced by automatic positive pressure respiration.

(7) Infection of pulmonary and tracheobronchial tree plays a major role after 48 hr and early antibiotic coverage may help to control it.
TOXIC FACTORS AND PROTEOLYTIC ENZYMES IN BURNS*
Authors: Shun‐Schinella Clara K. , Stanford John W. , Greenberg† Jacob , Annecchiarico Frank J. , Fox Charles L.
Published: December 2006

All preparations bioassayed were sterile. In addition, incorporation of antibiotics during preparation of the skin extract did not lessen the mortalities. The toxicity of the dialyzed mouse skin extract is not due to the presence of bacteria.

In searching for factors which cause death in burn patients receiving therapy, we investigated the skin as a source of toxic factors. Both normal and burned skin, when processed as described, yielded sterile extracts which caused death in saline‐treated scalded mice. By means of ammonium sulfate precipitation and Sephadex chromatography of this extract, fractions having enzymatic activity have been obtained. These fractions also proved toxic to saline‐treated scalded mice. Isolation and identification of the active material may contribute to understanding the cause of death in burn patients and hopefully to therapy.
RESPIRATORY DISEASE THE CURRENT TARGET FOR ANTIVIRAL THERAPY
Authors: Warren Joel
Published: December 2006

If we accept the premise that the systemic viral exanthemata, as measles, rubella, varicella, and variola, as well as poliomyelitis, are controllable with current and future vaccines, the discussion this evening is primarily related to respiratory disease. Furthermore, if we exclude infectious hepatitis, there are few known viral diseases of significant incidence which justify energetic antiviral research.
ADHESION OF PLATELETS TO SUBENDOTHELIUM
Authors: Baumgartner Hans R. , Haudenschild Christian
Published: December 2006

Endothelium provides the physiologic nonthrombogenic surface in vivo. Connective tissue components underneath the endothelial lining form the subendo‐thelium. The subendothelial surface appears far less thrombogenic than collagen fibers. Platelet adhesion to subendothelium as an entity is greatly enhanced by the presence of other blood cells, by an increase in the flow rate of the circulating blood, and by the presence of divalent cations. The affinity of platelets to different connective tissue components of the subendothelium varies markedly. When exposed to the same blood stream in a newly developed perfusion chamber, the affinity of platelets to the respective material decreases in the following order: collagen fibers, amorphous material (basement membrane), microfibrils, and elastin.
THE EFFECT OF ORAL CONTRACEPTIVES ON FIBRIN‐CLOT STABILIZATION*
Authors: Shanberge J. N. , Tanaka K. , Gruhl M. C. , Ikemori R. , Inoshita K.
Published: December 2006

In studying the stability of fibrin clots formed from native plasma, in 1% monochloroacetic acid, it has been found that at a given temperature there is a variation among individuals. Clots formed from normal young adult females are more stable than those from males, but those formed from females taking contraceptive medication are significantly more stable than those of males or females not on contraceptives. Increased fibrin clot stability in females on oral contraceptive medication is not related to the increased fibrinogen level or to the level of fibrin‐stabilizing factor (Factor XIII) in such individuals.
TESTING MORPHOLOGICAL PRODUCTIVITY
Authors: Aronoff Mark , Schvaneveldt Roger
Published: December 2006

We have shown how an experimental technique borrowed from cognitive psychology, the Lexical Decision Task, can be used to study morphology. In particular, we have shown that native speakers of English respond positively more often to novel words of the form Xiveness than they do to words of the form Xivity, a result which was predicted from the greater productivity of the former pattern, as determined by techniques of linguistic analysis. Our finding holds true under a variety of instructions. While the result of our study is not particularly surprising, we hope that in demonstrating that the Lexical Decision Task is a reliable tool in the study of morphology we will encourage further research along the lines that we have developed.
CLINICAL CRITERIA OF BRAIN DEATH *
Authors: Allen Norman , Burkholder James , Comiscioni John
Published: December 2006

Summary

Analyses have been performed upon data derived from 503 patients having coma and apnea in the Collaborative Study of Cerebral Survival and from subsets of 44 survivors and 102 cases in which details of temporal course and outcome were specified. Three methods of analysis were employed. The first consisted of correlation of proposed clinical signs with a series of presumptive definitions of brain death, the most rigorous of which included pathologic diagnosis. The second dealt with a conservative definition of brain death based upon the condition of electrocerebral silence with comparison of time course of clinical signs in patients having presumptive brain death versus that in patients who survived. Third, discrimination value of individual signs and combinations was evaluated by phi coefficients in relationship of presumptive brain death versus cases without evidence of brain death. These analyses lead to the exclusion of some of the proposed clinical signs. Body temperature and blood pressure showed no correlational trend and had no discriminative value. The spinal reflexes showed high persistence rates in cases of presumptive brain death and also had low phi coefficients. Some reflexes, the audio‐ocular and abdominal, were excessively sensitive, being commonly absent both in brain death as well as in non‐brain death cases and survivors. The snout and jaw reflexes were the two cephalic reflexes most likely to persist in presumptive brain death and to have low phi coefficients. The clinical signs recommended as diagnostic criteria include: coma, apnea, and the absence of the light, vestibular, oculocephalic and corneal reflexes. These criteria existed in the absence of severe hypothermia (below 90|Mo F) or drug intoxication. The four cephalic reflexes were identified on the basis of prevailing absence in presumptive brain death, return in cases ultimately surviving, and high phi coefficients. Spontaneous movements are of borderline clinical value but may be retained in view of lay interpretations. Pupillary dilatation is not a criterion, except in the cases of brain death due to cardiac arrest. The pharyngeal, swallow and cough reflexes need not be criteria for brain death, but are of value in the sequential identification of drug‐intoxicated survivors. EEG recording is necessary in addition to the clinical criteria in order to avoid incorrect identification of brain death in patients with primary brain‐stem disorders and in potential survivors.
A GENERALIZATION OF DIRACS THEOREM* ON TRIANGULATED GRAPHS
Authors: Golumbic Martin Charles
Published: December 2006

Summary

Golumbic and Goss [5] introduced the class of chordal bipartite graphs, which was shown to be the bipartite analog of triangulated graphs. This paper completes the connection by proving a stronger theorem for chordal bipartite graphs and by deriving some previously known results on triangulated graphs.
THERE IS ONE HADAMARD MATRIX OF ORDER 24 AND BOTH CHARACTERS 1
Authors: Longyear Judith Q.
Published: December 2006

Summary

This paper is a part of the joint effort of N. Ito, J. Leon, and the author to determine the number of Hadamard matrices of order 24 which are inequivalent under transposition, row, or column permutation and row or column negation. The matrices of character at least 2 in either the plain or transpose have been discussed earlier. Here we show there is a unique matrix with both characters one.
A BUDGET OF RHYME SCHEME COUNTS1
Authors: Riordan John
Published: December 2006

Summary

Rhyme schemes, perhaps the oldest combinatorial setting behind the Setting and Bell numbers, are rescued from current neglect by this budget of enumerations. A rhyme scheme for a stanza of n verses is a (number) sequence (r1, r2, …, rn) in which rj may be any of 1, 2, …, dj‐1+ 1, with dj the number of distinct numbers among r1, …, rj, the rhyme schemes for n= 3 are: 111, 112, 121, 122, 123. The total number of schemes for n verses is of course the Bell number Bn. They have a trivial mapping of set‐partitions but some enumerations familiar in the study of sequences are odd (even idiotic) when rephrased as set‐partitions. The budget displayed (by no means exhaustive) is selected for its interest in the study of Bell and Stirling numbers. One surprise is the appearance of refined Bell multivariable polynomials.
ON THE MOBILE RADIO FREQUENCY ASSIGNMENT PROBLEM AND THE TRAFFIC LIGHT PHASING PROBLEM
Authors: Roberts Fred S.
Published: December 2006

Summary

The problem of assigning frequencies to mobile radio telephones and the problem of assigning green light times to traffic streams at an intersection both deal with the assignment of a set S(x) to each vertex x of a graph G. The frequency assignment problem is concerned with set colorings: S(x) and S(y) are disjoint if x and y are joined by an edge. The traffic light phasing problem is concerned with set phasings: S(x) and S(y) are disjoint if x and y are not joined by an edge. This paper obtains some results on the existence and minimum size of set colorings and phasings under special restrictions on the sets S(x), for example, that each S(x) is a real interval or a set of n integers, or a set with at least a certain number of elements. Some of these results extend recent work on the n‐tuple chromatic number. Finally, the set phasing and coloring problems are related to the problem of assigning sets S(x) to vertices of a graph so that S(x) and S(y) overlap if and only if x and y are joined by an edge. Results about existence and minimum size of such set assignments are given.
FROM VITAMIN A TO RETINOIDS IN EXPERIMENTAL AND CLINICAL ONCOLOGY: ACHIEVEMENTS, FAILURES, AND OUTLOOK
Authors: Bollag W. , Matter A.
Published: December 2006

The problems of prevention and therapy of cancer are far from being solved. Regarding therapy, it is beyond doubt that surgery and radiotherapy cure a certain percentage of cancer patients. Cancer chemotherapy with the conventional cytostatic agents is a further means by which oncologists can help patients. Immunotherapy, including the newest methods of treatment with thymosin, and particularly interferon, may bring further progress. In the field of prevention of cancer mortality, early detection of precancerous and cancerous lesions and elimination of carcinogenic agents are up to now the most successful means. The continuing high mortality of cancer, even in the most developed countries, underlines the still unsatisfactory medical methods at our disposal. New approaches to the cancer problem are badly needed. It is the purpose of this conference to acquaint us with the basic research work done in the field of retinoids. The retinoids (vitamin A and analogs) represent a fairly new development in the cancer field, offering a new approach differing markedly in their more physiological mode of action from the hitherto existing approaches in prevention and therapy of cancer.
STUDIES OF Ca2+ RELEASE FROM SARCOPLASMIC RETICULUM*
Authors: MacLennan David H. , Shoshan Varda , Wood Donald S.
Published: December 2006

Summary

Our studies of Ca2+ release have shown that three classes of compounds—quercetin, which inhibits Ca2+ release by reversal of the Ca2+ pump, H+ ionophores and DCCD, which affect proton gradients, and lipophilic anions, which act to oppose a separation of membrane surface charges‐all have potential in probing the mechanism of Ca2+ release from sarcoplasmic reticulum.
STATISTICAL STRATEGIES FOR ANIMAL CONSERVATION*
Authors: Geller Nancy L.
Published: December 2006

Every time a particle of statistical method is properly used, fewer animals are employed than would otherwise have been necessary.1
Ultrastructure of Maturing Human Oocytes
Authors: SUNDSTRÖM P. , NILSSON B. O. , LIEDHOLM P. , LARSSON E.
Published: December 2006

The material for study consisted of 41 nonatretic oocytes obtained at follicular aspiration in women in whom ovarian stimulation had been carried out. Collected oocytes were clinically classified as preovulatory and immature by the amount, dispersion, and viscosity of cumulus‐corona cells surrounding the oocytes. Preovulatory oocytes are surrounded by a large, sticky and loose cumulus mass and immature oocytes by, at the most, a few layers of corona cells. Some oocytes were fixed immediately, but most preovulatory oocytes were incubated with spermatozoa and cultured for 2–3 days before fixation. All of these latter oocytes were unfertilized at fixation.
Interaction of Fibroblasts, Hemopoietic Cells and Platelets with Extracellular Matrix: Characterization and Role of a Common Cell Surface Glycoproteina
Authors: GIANCOTTI FILIPPO G. , COMOGLIO PAOLO M. , TARONE GUIDO
Published: December 2006

Cell adhesion to the extracellular matrix plays an important role in the complex phenomena involving cell motility, such as tumor metastasis1 and embryonic development.2 Interaction with the extracellular matrix is also required for the proper cellular response to growth and differentiation factors.3 A number of extracellular glycoproteins, which include fibronectin, laminin, vitronectin and collagens, are able to protnote cell adhesion by interacting with the plasma membrane.4 The complex and dynamic process of cell adhesion requires that, after binding to the adhesive factor, receptors in the plasma membrane either cluster and participate in the formation of adhesion plaques that are necessary for stable adhesion, or otherwise interact with the cytoskeletal motor to activate the tractional forces necessary for cell locomotion.5

In the present paper we will briefiy summarize some of our past work and report some new data on the identification, structural characterization and functional role of a mouse membrane glycoprotein implicated in the adhesion of fibroblasts, hemopoietic cells and platelets to the extracellular matrix.
Autoimmunity in Neuromuscular Disease
Authors: NEWSOM‐DAVIS JOHN
Published: December 2006

SUMMARY AND CONCLUSIONS

A number of confounding factors can be identified from the search for autoimmune mechanisms over the last 2 decades that may be relevant for future studies. (1) An apparently homogeneous clinical disorder may represent more than one disease process and thereby imply antibody/antigen heterogeneity as, for example, in MG with and without detectable anti‐AChR antibodies. In some cases, physiologic studies allow the different forms of the disease to be distinguished as in AIDP and acute inflammatory axonal poly neuropathy. (2) A homogeneous disorder (e.g., LEMS) may have at least two different triggering mechanisms (SCLC and an unknown stimulus). (3) Antigen density may be too low to be detected by the immunohistologic techniques available, as initially occurred in MG and LEMS. (4) Autoantibodies may be detected that are irrelevant to the primary disease, such as anti‐striated muscle antibodies in MG. (5) Poor antibody cross‐reactivity between species may mean that the pathogenic antibody is undetected in binding assays or in experimental passive transfer studies. For example, anti‐AChR antibody in MG shows less than 5% reactivity with Torpedo AChR. (6) A poor regenerative capacity of the target antigen may mean that reduction of circulating autoantibodies by either plasma exchange or ISD treatment is not associated with detectable clinical improvement, as may be the case in SSN in which DRG cells appear to be the target.

Table 5 summarizes the extent to which the data reviewed have established a role for pathogenic antibodies in the light of the postulates for autoimmunity set out earlier and ranks the disorders accordingly. Only in MG with detectable anti‐AChR antibody are all the postulates met, including definition of the antigen, experimental passive transfer by the IgG fraction of MG sera, active immunization of experimental animals, and propagation. In both LEMS and the IgMK anti‐MAG demyelinating neuropathy the antigen is known, although better characterized in LEMS; the epitopes are not yet denned in either. Data relating to passive transfer are more extensive in LEMS, however; systemic passive transfer of anti‐MAG has not yet been reported. In neither condition is an animal model available. In the demyelinating neuropathies, the case for autoimmunity is less complete. Neither in AIDP nor in CIDP is the antigen known, and thus the relevance of the different EAN disorders is uncertain. Current evidence thus rests on the demonstration of serum IgM antibodies that react with peripheral nerve myelin and fix complement and on the intraneural passive transfer studies. In some cases of MG without detectable anti‐AChR antibody, the passive transfer data are strongly suggestive of autoantibodies that are directed against determinants of the neuromuscular junction other than the AChR, and that may themselves be heterogeneous. Finally, in SSN there is currently no experimental evidence that the antineural nuclear antibody is directly implicated in the pathogenesis of DRG cell destruction.
Expression of Neural Cell Adhesion Molecules in Normal and Pathologic Tissues
Authors: BRACKENBURY ROBERT
Published: December 2006

Because cell‐cell and cell‐matrix interactions directly affect the growth, differentiation, and morphogenesis of neural tissue, abnormal changes in these processes could have severe pathologic consequences. Over the last few years, it has become possible to investigate these interactions at the molecular level due to advances in the identification and characterization of matrix components and receptors and cell adhesion molecules (CAMs). Emerging evidence suggests that two broad classes of CAMs are represented by the neural CAM, N‐CAM, and the epithelial CAM, L‐CAM. N‐CAM and several other neural adhesion molecules contain immunoglobulin‐like domains and do not require calcium for binding. In contrast, L‐CAM, N‐cadherin, and P‐cadherin depend on calcium for activity and share structural features that differ from those of the N‐CAM family. All of these CAMs are expressed in early embryos and in a variety of tissues throughout development, although each has a characteristic pattern. Initial studies suggest that injury, oncogenic transformation, and some genetic neurologic disorders are accompanied by changes in CAM expression that alter the adhesive or migratory behavior of cells.
The Spectrum of Ethical Issues Associated with the Military Support of Science and Technology
Authors: MITCHAM CARL
Published: December 2006

Philosophical and ethical issues associated with the relations between science, technology, and the military have been largely ignored by the contemporary professional philosophical community. This is not so true with regard to philosophers in the past, particularly political philosophers, or with nonprofessional philosophers in the present. For example, physical and biological scientists who have been involved in military or military‐funded projects, as well as social scientists (especially psychologists, economists, and historians), have initiated a number of relevant discussions.

The discipline of philosophy can, however, contribute to existing discussions by 1) offering conceptual clarifications of some empirical questions; 2) providing a framework for general interdisciplinary reflection; 3) promoting the synthesis of relevant information and arguments; and 4) offering criticism of some theoretical presuppositions entertained and positions advanced. To initiate such contributions, this introduction will indicate something of the general historicophilosophical background, then turn to a quick review of more immediate post‐World War II discussions. Along the way it will indicate some philosophical, often ethical, questions that deserve to be addressed. A conclusion will consider the role of ethics in its various dimensions.
Ethical Elements of Chemical/Biological Defense Research
Authors: LIEBMAN SHIRLEY A.
Published: December 2006

Personal and professional ethics both shape attitudes toward scientific research programs. Personal ethics are presented from the viewpoint of shared community responsibility and individual integrity combined with beliefs that guide relevant responses to defined needs. Professional ethics include personal motivation, accountability, and technical honesty as basic requirements for all research and development efforts, including defense‐oriented chemical and biological research. Industrial and military research issues of safety, confidentiality, and technical quality are addressed. Specific documented research in the field of trace organic chemical analysis is cited to show how federal laboratory programs contribute to the general scientific community. Technology assessment and transfer are considered as important means to ensure productive research efforts leading to economic benefits.
Nutrition and the Chemical Senses Problems and Opportunitiesa
Authors: HEGSTED D. MARK
Published: December 2006

Atwater's charts reduced the smell, taste, texture and weight of food to an essential nutritional line…. Were we today less accustomed to tables of proteins and calories, we might find it implausible that the son of a Temperance minister could entirely reconstrue the meanings of foods without reference to taste, ethnic tradition, or social context. Yet that is what Atwater did. (H. Schwartz, Never Satisfied, Viking Press, 1986)
Measurements of the Electric Dipole Moment of the Neutrona
Authors: HECKEL B. R. , LAMOREAUX S. K.
Published: December 2006

The origin of the CP violation discovered in the K0 system 25 years ago, remains uncertain.1,2 Assuming that CPT is conserved (where T is time reversal symmetry), a CP violating force can create a permanent electric dipole moment (EDM) on elementary particles such as the quarks and leptons, as well as on nondegenerate collections of particles such as the neutron, an atomic nucleus, or even atoms.3 Progressively decreasing experimental upper limits on the EDM of the bare neutron have helped narrow the range of models that attempt to explain CP violation (see ref. 4 for a recent review of the theory). In the standard model, the neutron EDM arises in second order of the weak interaction and is expected to be very small, of order 10−32e. cm. Most extensions to the standard model, however, allow the neutron EDM to be generated in first order of the weak interaction, making the expected value near 10−26 cm, close to the present experimental limit, or even larger.
CP Violation in K Decaysa
Authors: GILMAN FREDERICK J.
Published: December 2006

As in the case for much of contemporary research in high energy physics, the area of CP (the product of charge conjugation and parity) violation in K decays is to be seen in the context of a much broader effort of looking for physics beyond the Standard Model. One of the specific types of such physics is represented by the possibility of a fourth family, as exemplified by the title and main focus of this conference. From the broader perspective of looking for new physics of any kind, there are two principal avenues:
Effects of Various Tachykinins on Pituitary LH Secretion, Feeding, and Sexual Behavior in the Rata
Authors: KALRA SATYA P. , SAHU ABHIRAM , DUBE MICHAEL G. , KALRA PUSHPA S.
Published: December 2006

Our investigations of the four tachykinins tested have shown that NPK characteristically evoked a spectrum of biological effects in male and female rats. NPK suppressed pituitary LH release by inhibiting the release of hypothalamic LHRH, presumably by activation of NK‐2 tachykinin receptor subtypes. However, NPK may also act at the level of gonadotrophs to stimulate LH release in male rats. Central injection of NPK rapidly disrupted copulatory behavior in sexually active male rats. NPK also suppressed feeding, but, in this case, peripheral injections were more effective than central injections. Taken together, these observations strongly imply that NPK may be an inhibitory messenger molecule in the hypothalamic control of reproduction, sexual, and feeding behaviors.
Extremally Disconnected Compact Hausdorff Reflection
Authors: KUMAR VINOD
Published: December 2006

The rounding of o‐filters is introduced and this concept is used to construct an extremally disconnected compact Hausdorff reflection for a given extremally disconnected space. Some characterizations of such spaces have been obtained in terms of the rounding of o‐filters. Furthermore, relations between prime o‐filters, round o‐filters, ultra o‐filters, and skeletal maps have been established.
Homogeneity of Infinite Products of Manifolds with Boundary
Authors: YANG ZHANBO
Published: December 2006

It is shown that the countable product of connected, metrizable manifolds with boundary is homogeneous, strongly n‐homogeneous, strongly locally homogeneous in some enhanced sense, and n‐countable dense homogeneous for any positive number ε. Since a compact manifold is paracompact, it is metrizable. These results generalize those of M. K. Fort's results about products of compact manifolds with boundary.
Muscarinic Acetylcholine Receptor Subtypes Associated with Release of Alzheimer Amyloid Precursor Derivatives Activate Multiple Signal Transduction Pathways
Authors: FELDER CHRISTIAN C. , BRILEY EILEEN M. , AXELROD JULIUS
Published: December 2006

Five subtypes of muscarinic acetylcholine receptors have been identified and designated m1‐m5. The m1 and m3 receptors have recently been shown to stimulate APP processing. The m1 and m3 receptors couple to a variety of signal transduction pathways in both tissue slices and a variety of cell lines endogenously expressing either or both subtypes. In contrast, the m2 and m4 receptors have been primarily associated with inhibition of adenylate cyclase. We have transfected all five subtypes of muscarinic receptors into a variety of mammalian cell lines in order to investigate the signaling associated with single receptor subtypes. The m1, m3, or m5 receptors stimulate phospholipase A2, C, and D, adenylate cylase, receptor‐operated calcium channels, and tyrosine kinase activity simultaneously. The m2 or m4 receptor inhibits cAMP accumulation and augments a previously stimulated release of arachidonic acid and calcium influx.
Neurotransmitters and Second Messengers in Aging and Alzheimer's Disease
Authors: FRANCIS PAUL T. , WEBSTER M‐T. , CHESSELL I. P. , HOLMES C. , STRATMANN G. C. , PROCTER A. W. , CROSS ALAN J. , GREEN A. R. , BOWEN DAVID M.
Published: December 2006

A substantial loss of cortical cholinergic nerve endings, along with a much more circumscribed cortical degeneration of pyramidal neurons, almost certainly causes glutamatergic hypoactivity in live Alzheimer's patients. These selective pathologies are discussed in terms of therapy. An additional effect of some proposed treatments is emerging as there is evidence that processing pathways for β‐amyloid precursor proteins in cortical pyramidal neurons, a target cell for acetylcholine, are affected by neuronal activity.
Transmitters in the Developing and Senescent Human Brain
Authors: PERRY ELAINE K. , PIGGOTT MARGARET A. , COURT JENNIFER A. , JOHNSON MARY , PERRY ROBERT H.
Published: December 2006

During development and throughout adult life, modeling of CNS structure and function occurs as a result of experience. Transmitters play a central role in this mechanism both directly and indirectly (through control of neurotrophin expression) by governing synapse formation, elimination or consolidation. Cholinergic and excitatory amino acid transmitter system activities have been examined in postmortem human brain obtained from normal individuals varying from the prenatal period to old age. Whereas glutamate NMDA receptor binding (measured using MK801) was not substantially altered across the postnatal period, dramatic and differing patterns of choline acetlytransferase (ChAT) activity were evident. Thus, in the cerebellum, ChAT activity was 10‐fold higher in fetal compared to adult individuals whereas in the hippocampus there was little or no activity in the fetus and activity rose postnatally to reach a maximum in middle age and then declined to half that level by the tenth decade. Acetylcholinesterase (AChE) histochemical reactivity paralleled the developmental pattern for ChAT in the hippocampus and adjacent cortex with respect to fiber reactivity. These findings indicate that cholinergic synaptic plasticity may be restricted to the prenatal period in cerebellum but occur in both the postnatal period and throughout adult life in the hippocampus and cortex, a concept consistent with the temporal and regional expression of cholinoneurotrophins (NGF and related peptides). Vulnerability of the hippocampus and cortex to age‐related pathology such as β‐amyloidosis and neuritic plaque formation may relate to the extended period of cholinergic synaptic sculpting in these areas.
Abnormalities in Brain Glucose Utilization and Its Impact on Cellular and Molecular Mechanisms in Sporadic Dementia of Alzheimer Type
Authors: HOYER SIEGFRIED
Published: December 2006

Brain glucose utilization and ATP formation were found to be reduced to 54% and 81%, respectively, of control values in incipient sporadic dementia of Alzheimer type, causing reduced availability of the glucose‐derived neurotransmitter acetylcholine. With respect to energy shortage, impacts on energy‐dependent processes such as synaptic transmission, ion homeostasis, protein processing and degradation, extracellular transmission, and extracellular phosphorylation may be expected. Normal processing of the amyloid precursor protein was demonstrated to occur via a muscarinergic acetylcholine M1 and M3 receptor‐mediated signal transduction pathway. Since both the muscarinergic acetylcholine receptors on pyramidal neurons and G proteins were found to be unaltered in DAT, the possibility is discussed that the diminution of glucose utilization and the energy shortage in DAT brain may contribute considerably to abnormal amyloid precursor protein processing and thus to secondary amyloid formation.
Biologically Active Domain of the Secreted Form of the Amyloid β/A4 Protein Precursora
Authors: ROCH JEAN‐MARC , JIN LEE‐WAY , NINOMIYA HARUAKI , SCHUBERT DAVID , SAITOH TSUNAO
Published: December 2006

The amyloid β/A4 protein precursor (APP), a large transmembrane protein, is expressed ubiquitously in many organisms, as well as in a variety of cultured cells. Studies of the synthesis and processing of APP have revealed several intricate metabolic pathways for this protein. One of these pathways involves the cleavage of APP in the middle of the β/A4 domain and results in the secretion of the large amino‐terminal portion of the protein. The biological function of this secreted form of APP has been the subject of intense investigation by several groups and various activities have been described for the different domains of APP studied. Our initial approach was to create a fibroblast cell line in which APP expression is dramatically reduced. These fibroblasts, called A‐1, have a very slow growth rate. Addition of exogenous APP in the medium of A‐1 cells restores their growth to the level of normal parent fibroblasts, demonstrating a growth factor‐like activity for the secreted form of APP. Using APP fragments made in bacteria as well as synthetic peptides, we have been able to locate the active site of APP within a domain of 17 amino‐acids (Ala319‐Met335). This domain of APP can stimulate neurite extension of cultured neuroblastoma cells and it is proposed that APP mediates this effect through binding to a cell surface receptor, triggering intracellular transduction mechanisms. Thus, the secreted form of APP can function as a growth and/or differentiation factor and the site involved in these activities is within a 17‐mer domain in the middle of the molecule. Our current lines of research seek to further characterize the mechanisms of APP function as well as its activity in vivo.
A New Hypothesis for the Mechanism of Amyloid Toxicity, Based on the Calcium Channel Activity of Amyloid β Protein (AβP) in Phospholipid Bilayer Membranes
Authors: POLLARD HARVEY B. , ROJAS EDUARDO , ARISPE NELSON
Published: December 2006

Amyloid β protein (AβP) is the 40–42 residue polypeptide implicated in the pathogenesis of Alzheimer's disease (AD). We have reconstituted this peptide into phosphatidylserine liposomes and then fused the liposomes with a planar lipid bilayer. When incorporated into this bilayer, the AβP forms cation selective channels capable of transporting calcium and some monovalent cations including cesium, lithium, potassium, and sodium. The channels behave in an ohmic fashion and single channels can be shown to exhibit multiple subconductance states. Hitherto, AβP has been presumed to be neurotoxic, although direct demonstration of toxicity has proved elusive. On the basis of the present data we suggest that the ion channel activity of the polypeptide may be the basis of its neurotoxic effects.
The βA4 Amyloid Protein Precursor in Human Circulationa
Authors: BUSH ASHLEY I. , BEYREUTHER KONRAD , MASTERS COLIN L.
Published: December 2006

βA4, the principal constituent of the brain amyloid collections in Alzheimer's disease, is derived from a much larger precursor, the amyloid protein precursor (APP). APP exists in the blood as full‐length, potentially amyloidogenic forms in platelets, and as an attenuated species in plasma and T‐lymphocytes. Studies of circulating APP facilitate the elaboration of the function of this protein, as well as the elucidation of its processing in health and disease.
Experimental Induction of β‐Amyloid Plaques and Cerebral Angiopathy in Primatesa
Authors: BAKER H. F. , RIDLEY R. M. , DUCHEN L. W. , CROW T. J. , BRUTON C. J.
Published: December 2006

Moderate numbers of amyloid plaques with associated argyrophilic dystrophic neurites and cerebral amyloid angiopathy (CAA) but no neurofibrillary tangles (NFTs) were found in the brains of 3 middle‐aged common marmosets (Callithrix jacchus) inoculated intracerebrally (i.e.) 6–7 years earlier with brain tissue from a patient with early onset Alzheimer's disease. The plaques and vascular amyloid stained positively with antibodies to β(A4)‐protein. The brains of 3 age‐matched control marmosets from the same colony did not show these neuropathological features, β‐amyloid plaques and CAA (but no spongiform encephalopathy) were also found in the brain of a marmoset inoculated with brain tissue from a patient with priori disease with concomitant β‐amyloid plaques and CAA. An occasional β‐amyloid plaque was found in the brains of two marmosets inoculated with brain tissue from elderly patients. No β‐amyloid plaques nor CAA were found in 6 other marmosets who were older than the inoculated marmosets, 10 further marmosets who were slightly younger but who had been inoculated several years previously with brain tissue which did not contain β‐amyloid, and 10 younger marmosets who had been subjected to various neurosurgical procedures. These results suggest that β‐amyloidosis is a transmissible process.
The Age of Biosenescence and the Incidence of Cerebral β‐Amyloidosis in Aged Captive Rhesus Monkeysa
Authors: UNO H. , WALKER L. C.
Published: December 2006

Autopsy surveillance of 186 rhesus monkeys aged 20 to 36 years revealed that development of major geriatric diseases such as emphysema, coronary sclerosis, and cancer increased rapidly after the age of 25 years, and nearly 70% of the monkeys in each cohort group died by 30 years. According to our 12‐year longitudinal survey, the age of biosenescence in captive rhesus monkeys begins around 25 years and the maximum longevity is 36 years. The incidence of cerebral β‐amyloidosis associated with plaque formation and cerebral angiopathy was observed in 51 brains of rhesus monkeys aged 25 to 36 years. Lesions were found in 31 of 51 aged brains (60%) and 6 monkeys over 34 years of age were all severely affected. Despite the size of the plaque, nearly all of them showed immunopositive β‐amyloid. Cerebral angiopathy coexisted in 10 of 31 plaque‐positive brains. The basal prefrontal gyms was the most common site and contained the highest density of plaques, followed by the amygdala region. The amyloid in the liver, spleen, adrenal and pancreatic islets in visceral amyloidosis showed no positivity to the β‐amyloid demonstrated in the brain. As in aged human brains, the incidence of age‐dependent cerebral β‐amyloidosis in captive rhesus monkeys showed great individual variation.
Selective Signaling via Unique Ml Muscarinic Agonistsa
Authors: FISHER ABRAHAM , HELDMAN ELIAHU , GURWITZ DAVID , HARING RACHEL , BARAK DOV , MESHULAM HAIM , MARCIANO DANIELE , BRANDEIS RACHEL , PITTEL ZIPORA , SEGAL MENAHEM , VOGEL ZVI , KARTON YISHAI
Published: December 2006

Rigid analogs of acetylcholine (ACh) were designed for selective actions at muscarinic receptor (mAChR) subtypes and distinct second messenger systems. AF102B, AF150, and AF151 are such rigid analogs of ACh. AF102B, AF150 and AF151 are centrally active M1 agonists. AF102B has a unique agonistic profile showing, inter alia: only part of the M1 electrophysiology of ACh and unusual binding parameters to mAChRs. AF150 and AF151 are more efficacious agonists than AP102B for M1 AChRS in rat cortex and in CHO cells stably transfected with the ml AChR subtype. Notably, the selectivity of the new ml agonists is reflected also by activation of select second messenger systems via distinct G‐proteins. These compounds reflect a new pharmacological concept, tentatively defined as ligand‐selective signaling. Thus, agonist/m1AChR complexes may activate different combinations of signaling pathways, depending on the ligand used. Rigid agonists may activate a limited repertoire of signaling systems. In various animal models for Alzheimer's disease (AD) the agonists AF102B, AF150 and AF151, exhibited positive effects on mnemomic processes and a wide safety margin. Such agonists, and especially AF102B, can be considered as a rational treatment strategy for AD.
Acetyl‐l‐Carnitine and Alzheimer's Disease: Pharmacological Considerations beyond the Cholinergic Spherea
Authors: CARTA A. , CALVANI M. , BRAVI D , BHUACHALLA S. NÍ
Published: December 2006

Since ALCAR and l‐carnitine are “shuttles” of long chain fatty acids between the cytosol and the mitochondria to undergo β‐oxidation, they play an essential role in energy production and in clearing toxic accumulations of fatty acids in the mitochondria. ALCAR has been considered of potential use in senile dementia of the Alzheimer type (SDAT) because of its ability to serve as a precursor for acetylcholine. However, pharmacological studies with ALCAR in animals have demonstrated its facility to maximize energy production and promote cellular membrane stability, particularly its ability to restore membranal changes that are age‐related. Since recent investigations have implicated abnormal energy processing leading to cell death, and severity‐dependent membrane disruption in the pathology of Alzheimer's disease, we speculate that the beneficial effects associated with ALCAR administration in Alzheimer patients are due not only to its cholinergic properties, but also to its ability to support physiological cellular functioning at the mitochondrial level. This hypothetical mechanism of action is discussed with respect to compelling supportive animal studies and recent observations of significant decrease of carnitine acetyltransferase (the catalyst of l‐carnitine acylation to acetyl‐l‐carnitine) in autopsied Alzheimer brains.
Activation PET as an Instrument to Determine Therapeutic Efficacy in Alzheimer's Diseasea
Authors: HEISS W. D. , KESSLER J. , SLANSKY I. , MIELKE R. , SZELIES B. , HERHOLZ K.
Published: December 2006

Forty patients with probable Alzheimer's disease (AD) were selected from a pool of 80 patients and assigned to 4 groups. Each received either social support, cognitive training only, or cognitive training in combination with pyritinol or phosphatidylserine. Treatment duration was 6 months. Before and after treatment the patients underwent neuropsychological testing as well as measurement of the regional cerebral metabolic rate for glucose using positron emission tomography (PET) and 2[18F]‐fluoro‐2‐deoxy‐D‐glucose (FDG). Before treatment, the groups were comparable in respect to resting and activated glucose pattern achieved by a visual recognition task. They did not differ in scores of a neuropsychological test battery. After the treatment period the group with cognitive training + phosphatidylserine showed a significant glucose enhancement during the stimulation tasks in various brain regions, and an improvement in cognitive functioning compared to the other groups. The group with cognitive training + pyritinol had better stimulation effect as that of the social support group indicating that a combination of cognitive training + pharmacological intervention was superior than that of cognitive training alone.
Beyond the Standard Model*
Authors: WILCZEK FRANK
Published: December 2006

The standard model of particle physics is marvelously successful. However, it is obviously not a complete or final theory. I shall argue here that the structure of the standard model gives some quite concrete, compelling hints regarding what lies beyond.
Some Cardinal Inequalities in Lindelöf Spaces
Authors: ALAS O. T.
Published: December 2006

ABSTRACT. Some bounds on the cardinality of Lindelöf T1‐spaces such that small subspaces verify a meta‐Lindelöf property are proved. A procedure to extend these results to a larger class of spaces is shown.
Accessible and Biaccessible Points in Contrasequential Spacesa
Authors: DOW ALAN , VAUGHAN JERRY E.
Published: December 2006

ABSTRACT. Two countable spaces having no nontrivial convergent sequences are constructed. One space has every point biaccessible (by a countable discrete set), and the other has every point accessible but not biaccessible (by a countable discrete set). It is shown that in a compact T2‐space if a set A is not closed, then there exists a free sequence contained in A whose closure is not contained in A. It follows that in a compact T2‐space of countable tightness, every nonisolated point is biaccessible.