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1.
Phys Rev Lett ; 111(24): 243201, 2013 Dec 13.
Article in English | MEDLINE | ID: mdl-24483657

ABSTRACT

We present an experimental determination of the 2p3d(1Po)→1s3d(1De) x-ray line emitted from He-like Si, S, and Cl projectile ions, excited in collisions with thin carbon foils, using a high-resolution bent-crystal spectrometer. A good agreement between the observation and state-of-the-art relativistic calculations using the multiconfiguration Dirac-Fock formalism including the Breit interaction and QED effects implies the dominance of fluorescent decay over the autoionization process for the 2p3d(^{1}P^{o}) state of He-like heavy ions. This is the first observation of the fluorescence-active doubly excited states in He-like Si, S, and Cl ions.

3.
J Anim Breed Genet ; 125(2): 84-8, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18363973

ABSTRACT

The effect of parental genotype and paternal heterosis on litter size (LS), total litter birth weight (TLW) and average litter birth weight (ALW) was analysed utilizing data from a crossbreeding programme involving the exotic German Fawn goats and local Katjang goats in Malaysia. In this study, these traits were regarded as traits of the litter to consider the effect of service sire genotype. The results revealed that LS was significantly influenced by the genotype of sire. The genotypes of sire and dam had significant effects on TLW and ALW. Estimates of crossbreeding parameter showed significant and negative influence of paternal heterosis on TLW and ALW while there was no significant effect of paternal heterosis on LS. The results of this study stress the need to reconsider the use of local males in the tropics.


Subject(s)
Birth Weight/genetics , Goats/genetics , Litter Size/genetics , Animals , Female , Genotype , Hybrid Vigor , Hybridization, Genetic , Malaysia , Male , Pregnancy
4.
J Chem Phys ; 126(1): 011104, 2007 Jan 07.
Article in English | MEDLINE | ID: mdl-17212483

ABSTRACT

Variational calculations using Hylleraas coordinates have been performed for the first time for estimating the energies of 3dnf((1,3)D(o)) state of helium for n=4,5,6. We predict absorption peaks at 12.219, 12.647, and 12.857 eV for the (3)D(o) series converging to N=3 ionization threshold of He(+) which can be expected to be observed in the experiment of single photon double excitation of lowest (3)P(e) state of helium placed in synchrotron radiation.

5.
J Chem Phys ; 123(19): 196102, 2005 Nov 15.
Article in English | MEDLINE | ID: mdl-16321117

ABSTRACT

Nonrelativistic energy of the (2p(2))(3)P(e) state of Be(2+) has been calculated using Ritz-variational method. The trial wave function is of Hylleraas type. The upper-bound energy E=-3.382 712 420 77 a.u. calculated by us is the lowest yet obtained.

6.
Proc Natl Acad Sci U S A ; 98(6): 3589-93, 2001 Mar 13.
Article in English | MEDLINE | ID: mdl-11248122

ABSTRACT

The effects of testosterone on early atherogenesis and the role of aromatase, an enzyme that converts testosterone to estrogens, were assessed in low density lipoprotein receptor-deficient male mice fed a Western diet. Castration of male mice increased the extent of fatty streak lesion formation in the aortic origin compared with testes-intact animals. Administration of anastrazole, a selective aromatase inhibitor, to testes-intact males increased lesion formation to the same extent as that observed with orchidectomized animals. Testosterone supplementation of orchidectomized animals reduced lesion formation when compared with orchidectomized animals receiving the placebo. This attenuating effect of testosterone was not observed when the animals were treated simultaneously with the aromatase inhibitor. The beneficial effects of testosterone on early atherogenesis were not explained by changes in lipid levels. Estradiol administration to orchidectomized males attenuated lesion formation to the same extent as testosterone administration. Aromatase was expressed in the aorta of these animals as assessed by reverse transcription-PCR and immunohistochemistry. These results indicate that testosterone attenuates early atherogenesis most likely by being converted to estrogens by the enzyme aromatase expressed in the vessel wall.


Subject(s)
Aromatase/physiology , Coronary Artery Disease/pathology , Estradiol/metabolism , Testosterone/metabolism , Animals , Aorta/enzymology , Aromatase/genetics , Aromatase Inhibitors , Cholesterol/blood , Coronary Vessels/drug effects , Coronary Vessels/pathology , Estradiol/administration & dosage , Estradiol/blood , Estradiol/pharmacology , Gene Expression , Lipoproteins, HDL/blood , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Orchiectomy , Testosterone/administration & dosage , Testosterone/blood
7.
Infect Immun ; 68(7): 4084-91, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10858225

ABSTRACT

Almost one-third of the world population today harbors the tubercle bacillus asymptomatically. It is postulated that the morphology and staining pattern of the long-term persistors are different from those of actively growing culture. Interestingly, it has been found that the morphology and staining pattern of the starved in vitro population of mycobacteria is similar to the persistors obtained from the lung lesions. In order to delineate the biochemical characteristics of starved mycobacteria, Mycobacteria smegmatis was grown in 0.2% glucose as a sole carbon source along with an enriched culture in 2% glucose. Accumulation of the stringent factor guanosine tetraphosphate (ppGpp) with a concomitant change in morphology was observed for M. smegmatis under carbon-deprived conditions. In addition, M. smegmatis assumed a coccoid morphology when ppGpp was ectopically produced by overexpressing Escherichia coli relA, even in an enriched medium. The Mycobacterium tuberculosis relA and spoT homologue, when induced in M. smegmatis, also resulted in the overproduction of ppGpp with a change in the bacterium's growth characteristics.


Subject(s)
Guanosine Tetraphosphate/metabolism , Mycobacterium smegmatis/cytology , Mycobacterium smegmatis/metabolism , Escherichia coli/genetics , Gene Expression , Genes, Bacterial , Genetic Complementation Test , Glucose/metabolism , Humans , Intracellular Fluid/metabolism , Kinetics , Ligases/genetics , Mycobacterium Infections, Nontuberculous/microbiology , Mycobacterium smegmatis/genetics , Mycobacterium smegmatis/growth & development , Mycobacterium tuberculosis/genetics , Pyrophosphatases/genetics
8.
Anim Genet ; 28(1): 1-13, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9124701

ABSTRACT

Genetic variation at 53 protein-coding loci (25 polymorphic) was analysed for 17 water buffalo populations-12 swamp, three Lankan and two of the Murrah breed (river type), to determine the magnitude of genetic differentiation and the genetic relationships among the populations. In accord with previous cytological studies, the Lankan buffalo clearly are river type. Significant deviations from Hardy-Weinberg equilibrium were shown for a number of locus-population combinations, with all populations but one showing significant heterogeneity in these deviations among loci. By contrast, heterogeneity among populations for each locus was much less, indicating locus-specific deviations, which suggest selection affecting allele frequencies at some loci. There was significant genetic differentiation among populations of both the swamp and river types. The differentiation among the swamp populations may reflect the geography of south-east Asia and the presumed spread of the swamp buffalo through this region. Phylogenies derived from pairwise genetic distance estimates show the clear separation of swamp and river types, but the topology of the swamp populations shows rather poor consistency with their geographic locations. For at least one population (Australia), it is clear that bottleneck effects have distorted the phylogenetic topology. Average genetic distances for both the swamp and river types, as compared with previous studies of livestock breeds, show that the genetic differentiation of each of these sets of populations is of the same order of magnitude as that among well-recognized and established breeds of other species.


Subject(s)
Buffaloes/genetics , Genetic Variation , Phylogeny , Animals , Asia, Southeastern , Enzymes/blood , Gene Frequency , Genotype
9.
J Anim Breed Genet ; 114(1-6): 191-9, 1997 Jan 12.
Article in English | MEDLINE | ID: mdl-21395815

ABSTRACT

SUMMARY: Growth performance data of the local goats of Malaysia and their crossbreds with the German (Improved) Fawn goats were analysed using animal models with maternal effects, in order to estimate additive genetic and crossbreeding parameters. Two different genetic models, the Dickerson (1969, 1973) model and the Kinghorn (1980, 1983) model, were used to estimate crossbreeding parameters. Coefficients of additive breed, heterosis (dominance), and recombination (epistatic) loss were fitted in the animal models as covariates. In general, the individual breed effects for birth, 6-month, and 9-month weights, and maternal breed effects for traits until weaning, were significant, indicating large differences for growth performance between the German Fawn and the local breeds. Heterosis effects by the Dickerson model were small and non-significant, while dominance effects by the Kinghorn model, for some of traits, were large and significant. Highly significant individual recombination loss effects by the Dickerson model, and epistatic loss effects by the Kinghorn model, were obtained for birth and 9-month weights. The estimates of total heritability by an animal model incorporating maternal effects were moderate (0.18-0.35). The differences between heritabilities, estimated by different genetic models (the Dickerson model vs. the Kinghorn model), were small. ZUSAMMENFASSUNG: Genetische Parameter von Wachstumseigenschaften Malaysischer Lokalziegen und ihrer Kreuzung mit Deutscher Rehbrauner Ziege Die Daten wurden mittels Tiermodellen mit Maternalwirkung zur Schätzung additiv genetischer und Kreuzungsparameter analysiert. Zur Schätzung letzterer wurden Modelle von Dickerson (1969, 1973) und Kinghorn (1980, 1983) angewendet. Koeffizienten der additiven Rassenwirkungen, Heterosis (Dominanz) und Rekombinations-wirkungen wurden im Tiermodell als Kovarialbe berücksichtigt. Im allgemeinen waren individuelle Rassenwirkungen für Geburts-, 6- und 9-Monatsgewicht und maternale Rassenwirkungen für Merkmale während der Säugezeit signifikant, eine Folge großer Rassenunterschiede. Das Dickerson Modell führte zu geringen, nicht signifikanten Heterosiswirkungen, während beim Kinghorn Modell diese sich für mehrere Merkmale als groß und signifikant erwiesen haben. Hoch signifikante individuelle Rekombinationsverluste und epistatische Verluste ergaben sich bei beiden Modellen für Geburtsgewicht und 9 Monatsgewicht. Heritabilitätswerte waren mäßig hoch (0.18 bis 0.35), enthielten auch die maternalen Wirkungen und unterschieden sich zwischen beiden Modellen nur geringfügig.

10.
J Chromatogr A ; 707(2): 233-44, 1995 Jul 21.
Article in English | MEDLINE | ID: mdl-7633594

ABSTRACT

A high-performance liquid chromatography-electrospray ionization-mass spectrometric (LC-ESI-MS) method is presented that allows rapid and accurate determination of amino acid chiral purity in a peptide. Peptides are hydrolyzed in hydrochloric acid-d1/acetic acid-d4 and then converted to diastereomers by derivatization with 1-fluoro-2,4-dinitrophenyl-5-L-alanine amide (FDAA, Marfey's reagent). Mixtures of D- and L-amino acid diastereomeric pairs are resolved in one chromatographic separation using conventional reversed-phase high-performance liquid chromatography. Hydrolysis in a deuterated solvent is necessary because the original ratio of D-/L-amino acids present in a peptide changes during acid hydrolysis due to racemization. Peptide hydrolysis in deuterated acids circumvents this problem by labeling each amino acid that racemizes with one deuterium at the alpha-carbon. An increase in molecular mass of one atomic mass unit allows racemized amino acids to be distinguished from non-racemized amino acids by mass spectrometry. This procedure was used to determine the chiral purity of each amino acid in a purified, hexapeptide by-product (Arg-Lys-Lys-Asp-Val-Tyr) present in a kilogram batch of the synthetic pentapeptide, thymopentin (Arg-Lys-Asp-Val-Tyr).


Subject(s)
Chromatography, High Pressure Liquid/methods , Mass Spectrometry/methods , Peptides/isolation & purification , Alanine/analogs & derivatives , Alanine/chemistry , Amino Acid Sequence , Amino Acids/chemistry , Deuterium , Dinitrobenzenes/chemistry , Hydrolysis , Indicators and Reagents , Molecular Sequence Data , Peptides/chemistry , Protein Conformation
12.
Biochem Genet ; 31(5-6): 223-30, 1993 Jun.
Article in English | MEDLINE | ID: mdl-8259925

ABSTRACT

We have developed the methodologies for typing and family studies to establish the modes of inheritance of water buffalo red cell acid phosphatase (Acp), protease inhibitor (Pi), and group-specific component (Gc) on isoelectric focusing and albumin (Alb), red cell alpha-esterase-3 (Est-3), and catalase (Cat) on polyacrylamide gel electrophoresis. Family studies showed that Pi, Gc, Alb, and Cat are coded by autosomal genes with two codominant alleles, while Est-3 is autosomal with two codominant alleles and a recessive null allele and Acp exhibits three codominant alleles.


Subject(s)
Buffaloes/genetics , Erythrocytes/chemistry , Genetic Markers , Acid Phosphatase/blood , Acid Phosphatase/genetics , Alleles , Animals , Buffaloes/blood , Catalase/blood , Catalase/genetics , Erythrocytes/enzymology , Esterases/blood , Esterases/genetics , Female , Male , Phenotype , Protease Inhibitors/blood , Serum Albumin, Bovine/genetics , Vitamin D-Binding Protein/blood , Vitamin D-Binding Protein/genetics
13.
Anim Genet ; 19(1): 37-41, 1988.
Article in English | MEDLINE | ID: mdl-3377277

ABSTRACT

Genetic polymorphism of the 'X'-protein in red cells from Malaysian Katjang goats was demonstrated by starch gel electrophoresis at pH 7.3. Two new phenotypes were observed, suggesting that one new allele is involved. A new nomenclature for the 'X'-protein system in goats is proposed.


Subject(s)
Alleles , Blood Proteins/genetics , Erythrocytes/analysis , Goats/genetics , Polymorphism, Genetic , Animals , Goats/blood , Phenotype
14.
J Biol Chem ; 261(21): 9844-9, 1986 Jul 25.
Article in English | MEDLINE | ID: mdl-3090026

ABSTRACT

Apo-A-I, the major protein component of high density lipoproteins, appears intracellularly as an intermediate precursor (pro-apo-A-I) with a hexapeptide extension (RHFWQQ) at its amino terminus. Proteolytic processing of pro-apo-A-I to apo-A-I has been shown to occur extracellularly in cell and organ cultures from rat and human tissues. Recently, however, intracellular conversion has been detected in chickens. To determine what distinguishes and regulates these two processing methods, the proteolytic processing and secretion of apo-A-I was studied by metabolic labeling in chick hepatocytes and in Hep-G2 cells (derived from a human hepatocellular carcinoma). The proportions of intracellular and secreted pro-apo-A-I and apo-A-I were measured by sequencing NH2-terminal portions of the proteins and determining the location of radio-labeled amino acids. Chick hepatocytes cultured in the absence of hormones or fetal bovine serum secreted primarily processed apo-A-I (83%). In the presence of serum these cells secreted only pro-apo-A-I, whereas incubation with a combination of hormones (insulin, triiodothyronine, dexamethasone) resulted in secretion of a nearly equal mixture of the pro- and processed forms of the protein. In contrast, Hep-G2 cells, maintained in the absence of serum, secreted only pro-apo-A-I; when grown in the presence of serum these cells secreted a mixture of pro- and processed apo-A-I. Under conditions in which chick hepatocytes and Hep-G2 cells secreted both forms of the protein, a mixture of pro- and processed apo-A-I was also found intracellularly; when only the pro-form was secreted, the cells likewise contained only pro-apo-A-I. Under all the above conditions, the secreted apo-A-I exhibited similar isoform patterns in two-dimensional gel electrophoresis. These data show that both chick hepatocytes and human hepatoma cells are capable of intracellularly processing pro-apo-A-I to apo-A-I, and that the extent of intracellular processing is controlled by the cell's hormonal environment.


Subject(s)
Apolipoproteins A/metabolism , Liver/metabolism , Amino Acid Sequence , Animals , Apolipoprotein A-I , Blood , Cells, Cultured , Chick Embryo , Electrophoresis, Polyacrylamide Gel , Humans , Leucine/metabolism , Protein Precursors/metabolism
15.
J Biol Chem ; 261(20): 9521-5, 1986 Jul 15.
Article in English | MEDLINE | ID: mdl-2424912

ABSTRACT

Monospecific Kell blood group antibodies, of either human alloimmune or mouse monoclonal origin, react with a single surface-exposed protein of 93,000 daltons. Chymotryptic peptide maps of the 93,000-dalton protein isolated by antibodies of two different specificities (anti-K7 or anti-K14) indicate that Kell epitopes reside on the same protein. Kell protein is similar in size to band 3 protein but differs markedly in its tryptic and chymotryptic peptide maps, indicating that they are different proteins. In addition, sheep antibody to human band 3 does not react with Kell protein. Rabbit antibody to Kell protein reacts, by Western immunoblotting, with membrane proteins from Kell antigen positive red blood cells but not from those of a Ko (Kell null) cell. In intact red cells only a small portion of the Kell protein is available to lactoperoxidase-catalyzed iodination. Under nonreducing conditions Kell antigen is isolated not only as a 93,000-dalton protein but also as larger protein complexes ranging in size from above 200,000 to 115,000 daltons. Treatment of red cells with iodoacetamide, prior to isolation of Kell protein, reduces the amount of the very large complexes, but Kell protein occurs both as 115,000- and 93,000-dalton proteins.


Subject(s)
Blood Group Antigens/immunology , Erythrocyte Membrane/immunology , Kell Blood-Group System/immunology , Membrane Proteins/immunology , Animals , Anion Exchange Protein 1, Erythrocyte/immunology , Antigens/analysis , Chymotrypsin , Epitopes/analysis , Humans , Immunologic Techniques , Immunosorbent Techniques , Mice , Molecular Weight , Peptide Fragments/immunology , Phosphorylation , Trypsin
16.
J Cell Biol ; 101(4): 1219-26, 1985 Oct.
Article in English | MEDLINE | ID: mdl-3930506

ABSTRACT

To study the in vivo processing and secretion of Apolipoprotein A-I (Apo A-I), young chickens were administered individual L-[3H]amino acids intravenously and the time of intracellular transport of nascent Apo A-I from rough endoplasmic reticulum (RER) to the Golgi apparatus was measured. Within 3 to 9 min there was maximal incorporation of radioactivity into Apo A-I in both the RER and the Golgi cell fractions. By contrast, the majority of radioactive albumin was also present in the RER by 3 to 9 min, but did not reach peak amounts in the Golgi fraction until 9 to 25 min. Both radioactive Apo A-I and albumin appeared in the blood at about the same time (between 20 and 30 min). NH2-terminal amino acid sequence analysis of nascent intracellular Apo A-I showed that it contains a pro-hexapeptide extension identical to that of human Apo A-I. After 30 min of administration of radioactive amino acids radioactive Apo A-I was isolated by immunoprecipitation from the liver and serum. NH2-terminal sequence analysis of 20 amino acids indicated that chicken liver contained an equal mixture of nascent pro-Apo A-I and fully processed Apo A-I, whereas the serum only contained processed Apo A-I. Further studies showed that the RER only contained pro-Apo A-I, whereas a mixture of pro-Apo A-I and processed Apo A-I was found in the Golgi complex. These results indicate that, in chicken hepatocytes, there is a more rapid transport of Apo A-I than of albumin from the RER to the Golgi cell fractions, and that Apo A-I remains in the Golgi apparatus for a longer period of time before it is secreted into the blood. In addition these studies show that the in vivo proteolytic processing of chicken pro-Apo A-I to Apo A-I occurs in the Golgi cell fractions.


Subject(s)
Apolipoproteins A/metabolism , Lipoproteins, HDL/biosynthesis , Liver/metabolism , Albumins/metabolism , Amino Acid Sequence , Animals , Apolipoprotein A-I , Biological Transport , Chickens , Endoplasmic Reticulum/analysis , Golgi Apparatus/analysis , Protein Processing, Post-Translational
17.
Cytogenet Cell Genet ; 34(4): 315-9, 1982.
Article in English | MEDLINE | ID: mdl-7160233

ABSTRACT

Anatomical, histological, and cytogenetic studies were undertaken on a horned intersex goat kid and three of its normal litter mates. The intersex had male type horns, male beard, vestigial mammary glands, female external genitalia, and an enlarged peniform clitoris, exuded a pungent male odor, had a male bleat, and came into estrus every 20 days. At laparotomy and subsequent slaughter, an ovotestes was observed on the right side and a testis and epididymal remnants on the left side. Uterine horn segments, cervix, vagina, and enlarged clitoris (2 cm) were also present. Histologically, spermatogenesis was not observed in either testis, but active Leydig cells were present. The ovary contained mature follicles. Chromosome analysis revealed 60XX/60XY cell populations in blood, bone marrow, and skin. Lymphocytic metaphases from the male and female cosibs showed single populations of 60XY and 60XX, respectively. Mosaicism associated with the horned condition in the intersex goat was established.


Subject(s)
Disorders of Sex Development/veterinary , Goats/genetics , Mosaicism , Sex Chromosomes , Animals , Disorders of Sex Development/genetics , Disorders of Sex Development/pathology , Female , Genitalia/pathology , Male
18.
Obstet Gynecol ; 57(4): 447-9, 1981 Apr.
Article in English | MEDLINE | ID: mdl-7243091

ABSTRACT

Umbilical cord serum prolactin concentrations were determined in 17 full-term infants of mothers using narcotic agents during pregnancy and in 18 infants of similar birth weight and gestational age whose mothers did not use narcotics. The median value for the narcotic-exposed group was 266.6 ng/ml (range, 157.5 to 448.7 ng/ml); in the normal group the median was 193.7 ng/ml (range, 69.8 to 693.1 ng/ml). These differences were statistically significant (P less than .05). Although only full-term and borderline premature infants who were not appreciable risk for respiratory distress syndrome (RDS) were studied, it may be speculated that elevated prolactin blood levels in fetuses of addicted mothers may at least in part explain the reported decrease in the incidence of RDS in this group.


Subject(s)
Fetal Blood/analysis , Narcotics/pharmacology , Prolactin/blood , Birth Weight , Female , Gestational Age , Humans , Male , Maternal-Fetal Exchange , Opioid-Related Disorders/blood , Pregnancy
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