Completeness of seasonal molting in passerine birds (Aves,Passeriformes) in Northwestern Siberia

This paper considers the variability of the completeness of seasonal molting in passerine birds of the forest tundra and tundra areas of Western Siberia. All variants of passerine birds of North Eurasia known for molting—from complete postjuvenile molting at hatching places to its absence and complete postjuvenile molting at wintering places or at migratory routes, from complete prebreeding molting at wintering places to its absence, and from complete postbreeding molting at nesting places to complete molting at wintering places or at migratory routes—are shown. The factors affecting the completeness of molting are discussed—the properties of adaptation to the subarctic region, length of the migratory route, and photoperiodic conditions during molting. The completeness of molting is most significantly affected by the duration of daylight.     

A case of primary amenorrhea with 46+XY genotype from Kashmir Valley

Primary amenorrhea is one of the common reproductive disorder affecting females. It leads to the absence of menarche in the reproductive age group in females and/or complete absence of reproductive organs. There are many causes which lead to PA, including genetic aberrations which are the leading factors.     

Interpretation of isolated agenesis of the pituitary.

Cholesterol synthesis inhibitors administered to rats caused more or less complete forms of the holoprosencephalic syndrome, consisting of severe abnormalities of the brain, sense organs and pituitary. The absence of the pituitary was also observed in fetuses without externally visible cephalic abnormalities. These observations suggest that the isolated absence of the pituitary is the lesser form of the holoprosencephalic syndrome. This interpretation is also valid for cases of isolated absence of the pituitary observed in humans.     

Pentazocine-induced agranulocytosis.

A 46-year-old man with pentazocine-induced agranulocytosis is described. In previously reported cases of a complete absence of mature neutrophils in the peripheral blood and bone marrow the patients had undergone marrow-depressing treatment with radiation and antineoplastic drugs. This case is unique in that the patient had complete agranulocytosis without predisposing factors.     

Bacteriorhodopsin/amphipol complexes: structural and functional properties

The membrane protein bacteriorhodopsin (BR) can be kept soluble in its native state for months in the absence of detergent by amphipol (APol) A8-35, an amphiphilic polymer. After an actinic flash, A8-35-complexed BR undergoes a complete photocycle, with kinetics intermediate between that in detergent solution and that in its native membrane. BR/APol complexes form well defined, globular particles comprising a monomer of BR, a complete set of purple membrane lipids, and, in a peripheral distribution, ∼2 g APol/g BR, arranged in a compact layer. In the absence of free APol, BR/APol particles can autoassociate into small or large ordered fibrils.     

Complete Genome Sequence of the Porcine Isolate Enterococcus faecalis D32

The complete and annotated genome sequence of Enterococcus faecalis D32, a commensal strain isolated from a Danish pig, suggests putative adaptation to the porcine host and absence of distinct virulence-associated traits.     

Using the COG Database to Improve Gene Recognition in Complete Genomes

A complete understanding of the biology of an organism necessarily starts with knowledge of its genetic makeup. Proteins encoded in a genome must be identified and characterized, and the presence or absence of specific sets of proteins must be noted in order to determine the possible biochemical pathways or functional systems utilized by that organism. The COG database presents a set of tools suited to these purposes, including the ability to select protein families (COGs) that contain proteins from a specified set of species. The selection is based upon a phylogenetic pattern, which is a shorthand representation of the presence or absence of a particular species in a COG. Here we present the use of phylogenetic patterns as a means to perform targeted searches for undetected protein-coding genes in complete genomes.     

Binding of a 23 kD endonuclease to the rat liver nuclear matrix

In a previous paper we have described a 23 kD nuclear endonuclease (p23) that was mostly found to exist in a state of association with the isolated rat hepatocyte nuclear matrix. To investigate the nature of this interaction, the nuclear matrix was prepared using different procedures and examined for the presence/absence of the enzyme by activity gel analysis. Treatment of isolated nuclei with sodium tetrathionate (NaTT), a sulfhydryl-cross-linking agent, led to the complete recovery of p23 in the nuclear matrix, whereas incubation of nuclei with dithiothreitol (DTT), a sulfhydryl-reducing agent, led to its complete solubilization and resulting absence from the nuclear matrix. Exposure of the isolated nuclear matrix to DTT in high-ionic strength buffer, a procedure that promotes the solubilization of the internal nuclear matrix, caused the nearly complete solubilization of p23. It was concluded that disulfide bonds play an essential role in the association of p23 with the nuclear matrix and that p23 is mostly localized in the nuclear matrix interior.     

The PsbS protein controls the macro-organisation of photosystem II complexes in the grana membranes of higher plant chloroplasts

The PsbS protein is a critical component in the regulation of non-photochemical quenching (NPQ) in higher plant photosynthesis. Electron microscopy and image analysis of grana membrane fragments from wild type and mutant Arabidopsis plants showed that the semi-crystalline domains of photosystem II supercomplexes were identical in the presence and absence of PsbS. However, the frequency of the domains containing crystalline arrays was increased in the absence of PsbS. Conversely, there was a complete absence of such arrays in the membranes of plants containing elevated amounts of this protein. It is proposed that PsbS controls the macro-organisation of the grana membrane, providing an explanation of its role in NPQ.     

Effects of Light, Temperature, and pH Value on Aflatoxin Production In Vitro

In the complete absence of light, an isolate of Aspergillus flavus produced up to 170,000 pg aflatoxin per g, whereas the incubation of the fungus in light caused a reduction (35,000 pg/g) of the toxin synthesis.     

A profound deficiency in thymic progenitor cells in mice lacking Jak3

Humans and mice with genetic deficiencies that lead to loss of signaling through common gamma-chain (gammac)-containing cytokine receptors have severe defects in B and T lymphocytes. In humans, these deficiencies lead to a complete absence of T cells, whereas in mice, small thymuses give rise to normal numbers of peripheral T cells. We have examined the first wave of developing T cells in Jak3-/-, IL-7-/-, and IL-7Ralpha-/- fetal mice, and have found a near absence of thymic progenitor cells. This deficiency is highlighted by the complete inability of Jak3-/- progenitor cells to reconstitute T cell development in the presence of competing wild-type cells. These data clearly demonstrate a strong common basis for the T cell deficiencies in mice and humans lacking gammac/Jak3 signaling pathways.     

Metabolism of the carcinogen chromate by rat liver microsomes.

The metabolism of chromate by rat liver microsomes has been studied. Incubation of chromate with microsomes in the presence of the enzyme cofactor NADPH, resulted in reduction of chromate. In the absence of NADPH no reduction occurred. Only a small amount of chromate reduction was seen with NADPH in the absence of microsomes. Time course studies, microsome and NADPH concentration dependence studies resulted in conditions giving complete reduction of chromate. The possible relationship of metabolism of chromate to its carcinogenicity and mutagenicity is discussed.     

Phenotypic variability of the levels of autoantibodies against thyroglobulin and myoglobin in healthy individuals

Regularities of distribution of the levels of autoantibodies to thyroglobulin and myoglobin in healthy tweens were studied by immunoenzyme assay. The expressed variability, the absence of sex dimorphism and complete partypical determination of phenotypic variability of the levels tested were shown.     

Alpha-sarcin cleaves ribosomal RNA at the alpha-sarcin site in the absence of ribosomal proteins

alpha-Sarcin is capable of specifically cleaving the single phosphodiester bond in the "alpha-sarcin site" of both Escherichia coli and Saccharomyces cerevisiae large rRNAs in the absence of ribosomal proteins. With both sources of rRNA, the rate of cleavage was comparable with and without ribosomal proteins but more complete cleavage was observed in the absence of ribosomal proteins. These observations contrast with earlier findings and indicate that ribosomal proteins are not essential to the unique specificity of the cleavage of rRNA by alpha-sarcin.     

SOME FACTORS WHICH INFLUENCE THE OXIDATION OF SULFHYDRYL GROUPS

1. Cyanide inhibits the oxidation of the SH groups of cysteine and denatured egg albumin by the uric acid reagent. 2. At pH 4.8 cysteine is oxidized by the uric acid reagent and by ferricyanide in the presence but not in the absence of added copper sulfate. 3. In neutral solution, the uric acid reagent oxidizes the SH groups of denatured egg albumin in the presence of urea but not in the presence of alkyl sulfate or in the absence of denaturing agents. 4. Ferricyanide oxidizes the SH groups of neutral denatured egg albumin even in the presence of alkyl sulfate or, if precautions are taken to avoid aggregation, in the absence of denaturing agents. 5. In acid solution, ferricyanide does not oxidize the SH groups of denatured egg albumin completely. The oxidation is more complete, however, in the presence of urea than in the presence of alkyl sulfate, and more complete in the presence of guanidine hydrochloride than in the presence of urea. 6. The uric acid reagent which does not oxidize the SH groups of neutral denatured but unhydrolyzed egg albumin in the absence of denaturing agents does, under the same conditions, oxidize the SH groups of egg albumin partially hydrolyzed by pepsin. 7. At pH 4.8 in alkyl sulfate solution ferricyanide oxidizes the SH groups of digested egg albumin more completely than the SH groups of denatured but undigested egg albumin.     

Reproductive apparatus and mating system in two tropical goby species

Field observations demonstrated that two gobiid species Amblygobius nocturnus and Valenciennea muralis have a monogamous mating system. Histological analyses showed an extreme reduction of male accessory organs relative to other gobiids in A. nocturnus , and their complete absence in V. muralis.     

A,B and H isoantigens in atypical oral epithelium

Summary The red cell adherence (RCA) test was used for demonstration of blood group isoantigens A, B and H in epithelial lesions of the oral cavity. Study of normal squamous epithelium of the oral cavity with immunofluorescence showed the possible association of blood group isoantigens with the intercellular substance and their probable accumulation in spaces between desmosomes. In 31 cases of malignant tumors, a complete absence of isoantigens was found in 27 (87%), and partial loss in 2 (6.5%); in 2 cases of squamous cell carcinoma, the epithelial cells retained the isoantigen (6.5%). The second group of 34 cases included non-neoplastic changes such as leukoplakia, hyperkeratosis, dyskeratosis, pseudoepitheliomatous hyperplasia, or ballooning degeneration. A complete absence of isoantigens was found in 16 cases (47%), patchy distribution in 9 cases (26.5%); the remaining 9 cases (26.5%) retained the antigens. No correlation was found between the type and degree of epithelial atypia in non-neoplastic lesions and the absence of blood group substances. The loss of isoantigens A, B and H in neoplastic, pre-neoplastic, or even some regenerative or degenerative epithelial lesions suggests an aberration in their synthesis under abnormal conditions.     

Milk composition of rats feeding restricted litters.

Continuous assays of carnitine palmitoyltransferase were used to study the hysteretic behaviour of the enzyme. When reactions were started by adding mitochondria to complete reaction mixtures, there was a lag in the assay even in the absence of malonyl-CoA. When mitochondria were preincubated with malonyl-CoA in the absence of palmitoyl-CoA, there was a greater lag period in the assay of carnitine palmitoyltransferase, but this lag was less prominent at 37 degrees C than at 30 degrees C. Preincubation of mitochondria with malonyl-CoA did not change the sensitivity of the enzyme to inhibition by malonyl-CoA.     

Juvenile-onset loss of lipid-raft domains in attractin-deficient mice

Mutations at the attractin (Atrn) locus in mice result in altered pigmentation on an agouti background, higher basal metabolic rate and juvenile-onset hypomyelination leading to neurodegeneration, while studies on human immune cells indicate a chemotaxis regulatory function. The underlying biochemical defect remains elusive. In this report we identify a role for attractin in plasma membrane maintenance. In attractin's absence there is a decline in plasma membrane glycolipid-enriched rafts from normal levels at 8 weeks to a complete absence by 24 weeks. The structural integrity of lipid rafts depends upon cholesterol and sphingomyelin, and can be identified by partitioning within of ganglioside GM(1). Despite a significant fall in cellular cholesterol with maturity, and a lesser fall in both membrane and total cellular GM(1), these parameters lag behind raft loss, and are normal when hypomyelination/neurodegeneration has already begun thus supporting consequence rather than cause. These findings can be recapitulated in Atrn-deficient cell lines propagated in vitro. Further, signal transduction through complex membrane receptor assemblies is not grossly disturbed despite the complete absence of lipid rafts. We find these results compatible with a role for attractin in plasma membrane maintenance and consistent with the proposal that the juvenile-onset hypomyelination and neurodegeneration represent a defect in attractin-mediated raft-dependent myelin biogenesis.