bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dissociable mechanisms for memory impairment in bipolar disorder and schizophrenia
Authors: GLAHN DAVID C. , BARRETT JENNIFER , BEARDEN CARRIE E. , MINTZ JIM , GREEN MICHAEL F. , SERAP MONKUL E. , NAJT PABLO , SOARES JAIR C. , VELLIGAN DAWN I. 
Published: May 2006

Background. Although memory deficits are consistently reported in schizophrenia and bipolar disorder, the mechanisms underlying these impairments are poorly understood. Clarifying the nature and degree of overlap in memory deficits between the two illnesses could help to distinguish brain systems disrupted in these illnesses, and indicate cognitive remediation strategies to improve patient outcomes.Method. We examined performance on a non-verbal memory task in clinically stable out-patients with bipolar disorder (n=40), schizophrenia (n=40), and healthy comparison subjects (n=40). This task includes conditions in which distinct mnemonic strategies – namely, using context to organize familiar stimuli or using holistic representation of novel stimuli – facilitate performance.Result. When compared to a reference condition, bipolar patients had deficits consistent with organizational dysfunction and poor detection of novel information. Although patients with schizophrenia performed worse than the other groups, they were only differentially impaired when organizational demands were significant. Task performance was not correlated with severity of clinical symptomatology.Conclusions. This pattern of distinct memory impairments implies disturbances in partially overlapping neural systems in bipolar disorder and schizophrenia. Evidence of impairment in detection of novel stimuli that is unique to bipolar disorder suggests that, while the absolute level of cognitive dysfunction is less severe in bipolar disorder as compared to schizophrenia, subtle disruptions in memory are present. These findings can be used to plan targeted cognitive remediation programs by helping patients to capitalize on intact functions and to learn new strategies that they do not employ without training.
Varying temporal criteria for generalized anxiety disorder: prevalence and clinical characteristics in a young age cohort
Authors: ANGST JULES , GAMMA ALEX , JOSEPH BIENVENU O. , EATON WILLIAM W. , AJDACIC VLADETA , EICH DOMINIQUE , RÖSSLER WULF 
Published: May 2006

Background. This study questions the 6-month duration criterion for generalized anxiety disorder (GAD) used in DSM-III-R and DSM-IV.Method. In adults from age 20/21 to 40/41 in the prospective Zurich Cohort Study, four groups of generalized anxiety syndromes defined by varying duration (2 weeks, 1 month, 3 months and 6 months) were compared.Results. Applying DSM-III (1979–1999) and DSM-III-R (1986–1999) criteria, there were no significant differences between the four groups in terms of family history of anxiety, work impairment, distress, treatment rates or co-morbidity with major depressive episodes (MDEs), bipolar disorder or suicide attempts. Only social impairment related to the length of episodes. The 6-month criterion of DSM-III-R and DSM-IV GAD would preclude this diagnosis in about half of the subjects treated for generalized anxiety syndromes.Conclusions. In this epidemiological sample, the 6-month duration criterion for GAD could not be confirmed as clinically meaningful. GAD syndromes of varying duration form a continuum with comparable clinical relevance.
TEMPERATURE AND MANGANESE AS DETERMINING FACTORS IN THE PRESENCE OF DIATOM OR BLUE-GREEN ALGAL FLORAS IN STREAMS
Authors: Patrick Ruth , Crum Bowman , Coles John 
Published: May 2006

Diatoms are usually the major component of the algal flora in many streams, although green and blue-green algae may be present. These experiments were designed to determine if high temperature or a shift in the chemical composition of the water might bring about a dominance of blue-green algae and/or green algae rather than a dominance of diatoms in the algal flora.
The results of these experiments indicate that an average temperature of 34° to 38°C results in a shift of dominance in the algal flora from diatoms to blue-green algae. Furthermore, a blue-green and green algal flora of species typically found in organically polluted water in favored if the manganese content is a few parts per billion. If the manganese content averaged 0.02-0.043 mg/liter in the natural stream to 0.04-0.28 mg/liter in the recycled water experiment, a diatom flora remained dominant.
THE RELATIONSHIP OF THE INFLUENZA VIRUS INHIBITORY ACTIVITY OF GLYCOPROTEINS TO THEIR MOLECULAR SIZE AND SIALIC ACID CONTENT
Authors: Springer Georg F. , Schwick H. Gerhard , Fletcher Mary Ann 
Published: May 2006

Twenty-four different glycoproteins were investigated for their ability to inhibit hemagglutination by the A/PRS and the B/Md influenza virus strains. A relationship between activity, the molecular size, and sialic acid content was found. This relationship was readily shown for the A/PR8 virus if the properties of the glycoproteins were compared with one another on a per cent basis. A proportion of approximately 1:1:1 for activity (weight basis) to moles sialic acid content to molecular weight existed for each inhibitory glycoprotein with more than 3 per cent sialic acid, on comparison with any other active glycoprotein.
A 1:3 correspondence between viral subunit and sialic acid residues of the inhibitor ovine submaxillary mucin was found experimentally and confirmed by calculation on a molecular model. The most potent inhibitors, were the antigens of the human blood-group MN system and the Tamm-Horsfall urinary glycoprotein.
ACCELERATION BY THYMOSIN OF THE DEVELOPMENT OF RESISTANCE TO MURINE SARCOMA VIRUS-INDUCED TUMOR IN MICE
Authors: Zisblatt Martin , Goldstein Allan L. , Lilly Frank , White Abraham 
Published: May 2006

The development of resistance to progressive tumor growth and the effect of a thymic extract upon this developmental process were examined in CBA/Wh mice. Inoculating mice of various ages with murine sarcoma virus (Moloney) permitted the assessment of the period of time postnatally at which the animals developed a threshold level of resistance to progressive tumor growth. Resistance in CBA/Wh mice, at the virus dose used, was first detected at approximately two weeks of age and was completely developed at five weeks.
Thymosin, a soluble calf thymic fraction, when administered to neonatal mice beginning on the second day of life, significantly accelerated the rate of development of resistance to progressive tumor growth. The data suggest a humoral role for the thymus in the development of tumor immunity, and that the normal development of cell-mediated immunological competence can be accelerated through the use of thymus-derived extracts.
The Total Amino Acid Content of Fossil Pecten Shells
Authors: Akiyama Masahiko , Wyckoff Ralph W. G. 
Published: May 2006

Amino acid analyses have been made of the insoluble protein, soluble peptide, and free amino acid fractions isolated from a series of fossil pecten shells of ages from the Pleistocene through the Jurassic.
The total amino acid content declines progressively with age of the fossil but, in contrast to oyster shells, only a small fraction of the initial protein is present in the Pleistocene and older specimens. Though the thermally less stable acids are depleted in the free acid fraction, this is not true for the insoluble proteins and peptides. Large amounts of free amino acids and peptides persist through the Pliocene, considerable quantities of peptide have been recovered from the Miocene specimens, and even the oldest fossils have retained analyzable amounts of all three fractions.
Binding of Polycyclic Aromatic Hydrocarbons to Polyadenylic Acid
Authors: Craig A. Morrie , Isenberg I. 
Published: May 2006

A number of polycyclic aromatic hydrocarbons bind to the double-stranded, acid form of polyadenylic acid (poly A). Model building shows that these hydrocarbons may intercalate in the helix, and be well protected from contact with the aqueous medium. Hydrocarbons that are too large to be so protected are found not to bind. A size criterion for the binding of hydrocarbons to poly A therefore exists. This criterion differs from one that was previously found for DNA. The size criteria for DNA and poly A, together, serve as strong evidence for the intercalation model for hydrocarbon complexes.
Model-building experiments show that only a small portion of the hydrocarbon need extend into the medium to prevent binding. This finding implies that in two cases (1,2,5,6-dibenzanthracene·poly A and 3,4-benzpyrene·DNA) the structure of the complex is almost completely determined by the size criterion alone.
Neurotransmitter-Specific Synaptosomes in Rat Corpus Striatum: Morphological Variations
*
Authors: Gfeller Eduard , Kuhar Michael J. , Snyder Solomon H. 
Published: May 2006

This communication describes ultrastructural variations among synaptosomal fractions isolated from the corpus striatum of the rat by incomplete equilibrium sedimentation in sucrose density gradients, and attempts to relate the variations to neurotransmitter-specific synaptosomes. The concentration of synaptosomes in each fraction of the density gradient was found to be correlated with the concentration of potassium, a marker for cytoplasm occluded within synaptosomes. Monoamine oxidase activity was found to be correlated with the incidence of free mitochondria in the gradients.
Synaptosomes from denser gradient fractions showed a markedly increased frequency of adherent postsynaptic elements and intraterminal mitochondria. These denser gradient fractions were rich in synaptosomes containing norepinephrine, dopamine, serotonin, and acetylcholine, while synaptosomes in lighter portions of the gradients were rich in γ-aminobutyric acid and other amino acids. These data suggest that significant morphological variations may exist among different neurotransmitter-specific nerve terminals in the brain.
Association by Hydrogen Bonding of Mononucleotides in Aqueous Solution
Authors: Raszka Matthew , Kaplan Nathan O. 
Published: May 2006

Evidence for hydrogen bonding between 5′-ribonucleotides in water has been obtained from a 220-MHz proton magnetic resonance study of nitrogenous protons. The amino groups of GMP, AMP, and CMP exhibit proton resonance lines which are somewhat broadened by proton exchange with the solvent at 0°; their downfield Shifts in mixtures of mononucleotides provide the basis for the following order of base-pairing tendencies: GMP·CMP > AMP·UMP. Hydrogen bonding is also observed in other pairs of mononucleotides, notably GMP·UMP, AMP·CMP, and CMP·UMP, to a lesser extent in GMP·IMP, CMP·XMP, and possibly in CMP·IMP. In agreement with previous reports, hydrophobic interactions of mononucleotides have also been observed; base pairing occurs in addition to vertical stacking of these bases, their hydrogen bonding to water, or self-association. Only CMP shows clear evidence of self-association via hydrogen bonding in water; the evidence for GMP is less direct, and that for AMP is negative. This lack of observable self-association may occur as a result of competition from strong stacking interactions. Only CMP shows restricted rotation of the amino group at 0° and neutral pH. As expected, higher temperatures increase the rate of rotation of the amino group for CMP, as well as accelerate the rate of proton exchange between water and the amino protons of mononucleotides.
High-resolution proton magnetic resonance spectroscopy could prove to be a valuable tool in mapping out the specificities conferred by hydrogen bonding between biomolecules in aqueous solution.
Acetylcholine-Like Molecular Arrangement in Psychomimetic Anticholinergic Drugs
Authors: Maayani Saul , Weinstein Harel , Cohen Sasson , Sokolovsky Mordechai 
Published: May 2006

A study of the relation between the psychotropic activity and the antagonism to acetylcholine observed for some heterocyclic amino esters and compounds of the phencyclidine series suggests some common molecular structural requirements for their properties.
Criteria obtained from quantum mechanical calculations of acetylcholine-like molecules indicate that their molecular reactivity with the cholinergic receptor site follows a certain dynamic interaction pattern. This pattern suggests a certain molecular arrangement essential for the interaction, which is based on the electronic properties of the molecules and therefore remains valid for the evaluation of compounds which lack any apparent similarity to acetylcholine. This type of molecular arrangement is shown to be shared by both activators and inhibitors of the acetylcholine receptor discussed here, thus supporting the hypothesis of their binding to a common receptor. The differences in biological activity are attributed to the effect of molecular structural factors which are not commonly included in the molecular arrangement based on the active groups of acetylcholine. The role of such factors is revealed by a study of the observed differences in the cholinergic and psychomimetic activities of related pairs of isomers and enantiomers of the molecules investigated. Structural factors which interfere with the conformational changes occurring in the receptor protein induced by an activator are characterized through differences obtained by the comparative investigation of the activities of the agonist acetate and the antagonist benzilate amino esters of quinuclidine, tropine, and pseudotropine. The same factors are shown in studies of the phencyclidine series to contribute to the antagonism to acetylcholine activity that is closely related to the psychomimetic activity of these drugs in the central nervous system. Similarly, phencyclidine derivatives in which the characteristic acetylcholine-like molecular arrangement is modified by various substitutions are shown to loose both anticholinergic and psychotropic behavior. This close correlation is supported by the identification of molecular regions which will generate the proper molecular arrangement in local anesthetics and morphine, compounds which are known to be involved in cholinergic mechanisms.
The Nutritional Teamwork Approach: Prevention and Regression of Cataracts in Rats
Authors: Heffley James D. , Williams Roger J. 
Published: May 2006

We have taken advantage of a newly assimilated principle in nutrition: no nutrient by itself should be expected to prevent or cure any disease; nutrients as such always work cooperatively in metabolism as a team.
By feeding galactose-containing diets to young rats, cataracts are regularly produced. When, however, we furnished galactose-fed animals with what may be considered a well balanced, full team of nutrients, cataract prevention was accomplished. On four galactose-containing diets supplied with a full team of nutrients, not a single cataract developed in 24 rats (48 eyes). On four diets using the same dietary galactose challenge, accompanied with inadequate nutritional teams, 47 out of 48 eyes developed cataracts. Diets of intermediate quality induced the development of intermediate numbers of cataracts. Cataracts once formed were regressed slowly and incompletely by shifting the animals to a diet similar to that which had previously been found to protect against cataract formation.
The significance of these findings for nutritional research and for attacks on the problems of human cataracts and other ailments is discussed.
The Compression Hypothesis and Temporal Resource Partitioning
Authors: Schoener Thomas W. 
Published: May 2006

Contingency models of feeding compare the energy per unit time gained from utilizing a resource unit of a particular kind (food types, habitat patches, time periods) against that energy/time expected if the unit is skipped. Optimally, an animal should reject the particular unit if and only if the former energy/time is less than the latter. Consequently, food or habitat types should be excluded if the prospect of finding and consuming better types is sufficiently high. In contrast, feeding periods should be skipped only if it is less
costly
to wait than to feed.

In situations of high food abundance, contingency models imply that animals should be maximally specialized with respect to food or habitat type, but maximally generalized with respect to time period. As food decreases in abundance, food and habitat types should be added to the diet or itinerary, but time periods should be omitted from feeding activity. In contrast, animals with fixed caloric intake should broaden diet, habitat, and feeding times as abundance decreases.
According to contingency models, competitors cannot cause item kinds to be dropped from the diet, but because they can affect the values of patches once found, can cause habitat kinds to be dropped from the itinerary. Competitors also reduct the value of feeding during particular time periods, but ordinarily fairly severe depletion must occur before it is optimal to feed no longer in a period frequented by competitors.
These arguments imply that temporal resource partitioning on a diel basis should be relatively rare. In fact, specialization according to feeding period should differentially occur in animals of limited abilities to use or process available food, whereas that need not be the case for food-type or habitat specialization. It should also occur in animals sensitive to and found in variable climates.
RNA interference in the light brown apple moth, Epiphyas postvittana (Walker) induced by double‐stranded RNA feeding
Authors: Turner C. T. , Davy M. W. , MacDiarmid R. M. , Plummer K. M. , Birch N. P. , Newcomb R. D. 
Published: May 2006

AbstractRNA interference (RNAi) or gene silencing is typically induced in insects by the injection of double‐stranded RNAs (dsRNAs), short interfering RNAs, or through the use of hairpin constructs in transgenic insects. Here we demonstrate in the horticultural pest, Epiphyas postvittana (Lepidoptera: Tortricidae), that RNAi can be triggered by oral delivery of dsRNA to larvae. Transcript levels of a larval gut carboxylesterase gene (EposCXE1) were reduced to less than half that of controls within 2 days of being fed EposCXE1 dsRNA. Transcript levels of the pheromone binding protein gene (EposPBP1) were reduced in adult antennae by feeding larvae EposPBP1 dsRNA. Knockdown of EposPBP1 transcripts was observed for the first 2 days after adult eclosion but recovered to wild‐type levels at 4 days posteclosion. The potential mechanisms involved in the initiation, movement and amplification of the silencing signal are discussed.
Two Ser/Thr protein kinases essential for efficient aggregation and spore morphogenesis in Myxococcus xanthus
Authors: Stein Emily A. , Cho Kyungyun , Higgs Penelope I. , Zusman David R. 
Published: May 2006

Summary Myxococcus xanthus has a complex life cycle that involves vegetative growth and development. Previously, we described the espAB locus that is involved in timing events during the initial stages of fruiting body formation. Deletion of espA caused early aggregation and sporulation, whereas deletion of espB caused delayed aggregation and sporulation resulting in reduced spore yields. In this study, we describe two genes, pktA5 and pktB8, that flank the espAB locus and encode Ser/Thr protein kinase (STPK) homologues. Cells deficient in pktA5 or pktB8 formed translucent mounds and produced low spore yields, similar in many respects to espB mutants. Double mutant analysis revealed that espA was epistatic to pktA5 and pktB8 with respect to aggregation and fruiting body morphology, but that pktA5 and pktB8 were epistatic to espA with respect to sporulation efficiency. Expression profiles of pktA5–lacZ and pktB8–lacZ fusions and Western blot analysis showed that the STPKs are expressed under vegetative and developmental conditions. In vitro kinase assays demonstrated that the RD kinase, PktA5, autophosphorylated on threonine residue(s) and phosphorylated the artificial substrate, myelin basic protein. In contrast, autophosphorylation of the non‐RD kinase, PktB8, was not observed in vitro; however, the phenotype of a pktB8 kinase‐dead point mutant resembled the pktB8 deletion mutant, indicating that this residue was important for function and that it likely functions as a kinase in vivo. Immunoprecipitation of Tap‐tagged PktA5 and PktB8 revealed an interaction with EspA during development in M. xanthus. These results, taken together, suggest that PktA5 and PktB8 are STPKs that function during development by interacting with EspA and EspB to regulate M. xanthus development.
Enhanced Expression and Clinical Significance of CC‐Chemokine MIP‐3α in Hepatocellular Carcinoma
Authors: Rubie C. , Frick V. O. , Wagner M. , Rau B. , Weber C. , Kruse B. , Kempf K. , Tilton B. , König J. , Schilling M. 
Published: May 2006

AbstractHepatocellular carcinoma (HCC) is one of the most frequent visceral neoplasms worldwide. Using RT‐PCR, ELISA, microdissection and immunohistochemistry, we investigated the expression profiles of CCL19, CCL20, CCL21 and CXCL12 and their receptors in tumourous and tumour neighbouring tissues from patients with HCC and in nonmalignant liver lesions, respectively. All chemokines were found to be expressed in normal liver and HCC tissues, yet CCL20 was the only chemokine showing significant upregulation in HCC tissues. Clinicopathological analysis revealed a distinct increase in CCL20 expression rates in HCC tissues of grade III tumours in comparison to HCC tissues from grade II tumours. On mRNA level, only chemokine receptor CCR6 revealed significant upregulation in HCC tissues. However, immunohistochemical studies indicated a marked CCR6 expression accumulated in a streak of normal cells along the tumour invasion front in all our HCC specimens which could provide a stimulative signal for the tumour to further expand. The present findings show significant overexpression of CCL20 in the tumour tissues and marked overexpression of the corresponding receptor CCR6 in the tumour invasion front of HCC patients in comparison to normal liver. Moreover, CCL20 expression was found to correlate with tumour grade and therefore, we suggest that the CCL20/CCR6 system may be involved in hepatocarcinogenesis.