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1.
Blood specimens from Brahmin and Kamma caste populations of Coastal Andhra Pradesh, India are examined for A1A2BO, MNSs, and Rhesus blood groups. Predominance of A group in Brahmins and B group in Kammas is observed. Phenotype A2 records less than 4% in both populations. High frequencies of genes M, s, D, and e are exhibited among both populations. Statistically significant differences are found only for A1A2BO system between Brahmins and Kammas.  相似文献   

2.
2,596 Aroras and 2,629 Khatris comprising six endogamous groups of the Punjabis have been studied for A1A2BO blood groups and secretion of ABO(H) group specific substances. The values of chi-square and the genetical difference (G2) among these groups do not show statistically significant differences in these groups regarding the genetical characters studied. There is a closer affinity between Beri and Bunjahi on the one hand and Uttaradhi and Dhakhandian on the other and also between Uttaradhi and Khukhran; Dhakhandian and Sareen show a great difference among themselves as well as with other groups. The comparison of ABO blood group distribution and secretor factor among the different populations of India show that the distribution is similar among the North Indians.  相似文献   

3.
Summary Nearly three and a half thousand sera obtained from various populations were tested serologically to obtain evidence of past infection with influenza A viruses that were prevalent from 1947 to 1972.No significant difference was found between the distributions of the levels of these antibodies of individuals of blood groups A and 0, A1 and 0, Rh (D+) and Rh (D-) and MM, MN and NN.The significance of these findings is discussed.  相似文献   

4.
How population size influences quantitative genetic variation and differentiation among natural, fragmented populations remains unresolved. Small, isolated populations might occupy poor quality habitats and lose genetic variation more rapidly due to genetic drift than large populations. Genetic drift might furthermore overcome selection as population size decreases. Collectively, this might result in directional changes in additive genetic variation (VA) and trait differentiation (QST) from small to large population size. Alternatively, small populations might exhibit larger variation in VA and QST if habitat fragmentation increases variability in habitat types. We explored these alternatives by investigating VA and QST using nine fragmented populations of brook trout varying 50‐fold in census size N (179–8416) and 10‐fold in effective number of breeders, Nb (18–135). Across 15 traits, no evidence was found for consistent differences in VA and QST with population size and almost no evidence for increased variability of VA or QST estimates at small population size. This suggests that (i) small populations of some species may retain adaptive potential according to commonly adopted quantitative genetic measures and (ii) populations of varying sizes experience a variety of environmental conditions in nature, however extremely large studies are likely required before any firm conclusions can be made.  相似文献   

5.
Sex chromosomes in vertebrates range from highly heteromorphic (as in most birds and mammals) to strictly homomorphic (as in many fishes, amphibians, and nonavian reptiles). Reasons for these contrasted evolutionary trajectories remain unclear, but species such as common frogs with polymorphism in the extent of sex chromosome differentiation may potentially deliver important clues. By investigating 92 common frog populations from a wide range of elevations throughout Switzerland, we show that sex chromosome differentiation strongly correlates with alleles at the candidate sex-determining gene Dmrt1. Y-specific Dmrt1 haplotypes cluster into two main haplogroups, YA and YB, with a phylogeographic signal that parallels mtDNA haplotypes: YA populations, with mostly well-differentiated sex chromosomes, occur primarily south of the main alpine ridge that bisects Switzerland, whereas YB populations, with mostly undifferentiated (proto-)sex chromosomes, occur north of this ridge. Elevation has only a marginal effect, opposing previous suggestions of a major role for climate on sex chromosome differentiation. The Y-haplotype effect might result from differences in the penetrance of alleles at the sex-determining locus (such that sex reversal and ensuing X-Y recombination are more frequent in YB populations), and/or fixation of an inversion on YA (as supported by the empirical observation that YA haplotypes might not recombine in XYA females).  相似文献   

6.
The levels of blood lipid peroxidation, glutathione peroxidase, reduced glutathione, and vitamin C were used to follow the level of oxidative damage caused by 2.45 GHz electromagnetic radiation in rats. The possible protective effects of selenium and L-carnitine were also tested and compared to untreated controls. Thirty male Wistar Albino rats were equally divided into five groups, namely Groups A1 and A2: controls and sham controls, respectively; Group B: EMR; Group C: EMR + selenium, Group D: EMR + L-carnitine. Groups B–D were exposed to 2.45 GHz electromagnetic radiation during 60 min/day for 28 days. The lipid peroxidation levels in plasma and erythrocytes were significantly higher in group B than in groups A1 and A2 (p?<?0.05), although the reduced glutathione and glutathione peroxidase values were slightly lower in erythrocytes of group B compared to groups A1 and A2. The plasma lipid peroxidation level in group A2 was significantly lower than in group B (p?<?0.05). Erythrocyte reduced glutathione levels (p?<?0.01) in group B; erythrocyte glutathione peroxidase activity in group A2 (p?<?0.05), group B (p?<?0.001), and group C (p?<?0.05) were found to be lower than in group D. In conclusion, 2.45 GHz electromagnetic radiation caused oxidative stress in blood of rat. L-carnitine seems to have protective effects on the 2.45-GHz-induced blood toxicity by inhibiting free radical supporting antioxidant redox system although selenium has no effect on the investigated values.  相似文献   

7.
The role of the adenosine A3 receptor in hematopoiesis was studied using adenosine A3 receptor knockout (A3AR KO) mice. Hematological parameters of peripheral blood and femoral bone marrow of irradiated and untreated A3AR KO mice and their wild-type (WT) counterparts were investigated. Irradiation of the mice served as a defined hematopoiesis-damaging means enabling us to evaluate contingent differences in the pattern of experimentally induced hematopoietic suppression between the A3AR KO mice and WT mice. Defects were observed in the counts and/or functional parameters of blood cells in the A3AR KO mice. These defects include statistically significantly lower values of blood neutrophil and monocyte counts, as well as those of mean erythrocyte volume, mean erythrocyte hemoglobin, blood platelet counts, mean platelet volume, and plateletcrit, and can be considered to bear evidence of the lack of a positive role played by the adenosine A3 receptor in the hematopoietic system. Statistically significantly increased values of the bone marrow parameters studied in A3AR KO mice (femoral bone marrow cellularity, granulocyte/macrophage progenitor cells, and erythrocyte progenitor cells) can probably be explained by compensatory mechanisms attempting to offset the disorders in the function of blood elements in these mice. The pattern of the radiation-induced hematopoietic suppression was very similar in A3AR KO mice and their WT counterparts.  相似文献   

8.
Genotyping of 313 random individuals belonging to ten different population groups from three different states of India was performed for polymorphic pentanucleotide repeat present in the 5′ flanking region of nitric oxide synthase gene (NOS2A) to study the effect of geographical and linguistic affiliations on the genetic affinities among these groups. Likelihood ratio tests showed that all the ten populations for this locus were in Hardy-Weinberg equilibrium. Eleven different alleles ranging from 7 repeat to 17 repeats and 46 different genotypes were observed. The observed and the expected heterozygosity ranged from 0.72–0.94 and 0.84–0.89, respectively. The discriminating power of this locus is ≥ 0.86 and the polymorphism information content of this locus in ten population groups ranged from 0.80 to 0.85. High PIC, PD and PE value of this STR showed this marker to be informative and can be used for DNA typing and population studies. The eight populations from Kerala showed a lower G ST value of 0.016 compared to the G ST of ten populations (G ST = 0.019), thereby showing that the populations from the same state showed higher genetic proximity probably due to linguistic and geographical proximity between them. The article was received from the author in the original.  相似文献   

9.
A survey of nine blood group systems was conducted as part of a study of health and nutrition among two Athapsakan groups of the Yukon Territory, Canada. Most of the samples were also analyzed for hemoglobin patterns and G-6-PD variants. The only significant difference in allelic frequencies between the two populations occurred at the P locus. An apparent deficit in the observed frequency of type A1, and hence a departure from equilibrium, at Upper Laird could not be tested for significance due to insufficient degrees of freedom.  相似文献   

10.
11.
Spermatogonial stem cells (SSCs) reside in undifferentiated type-A spermatogonia and contribute to continuous spermatogenesis by maintaining the balance between self-renewal and differentiation, thereby meeting the biological demand in the testis. Spermatogonia have to date been characterized principally through their morphology, but we herein report the detailed characterization of undifferentiated spermatogonia in mouse testes based on their gene expression profiles in combination with topological features. The detection of the germ cell-specific proteins Nanos2 and Nanos3 as markers of spermatogonia has enabled the clear dissection of complex populations of these cells as Nanos2 was recently shown to be involved in the maintenance of stem cells. Nanos2 is found to be almost exclusively expressed in As to Apr cells, whereas Nanos3 is detectable in most undifferentiated spermatogonia (As to Aal) and differentiating A1 spermatogonia. In our present study, we find that As and Apr can be basically classified into three categories: (1) GFRα1+Nanos2+Nanos3Ngn3, (2) GFRα1+Nanos2+Nanos3+Ngn3, and (3) GFRα1Nanos2 ± Nanos3+Ngn3+. We propose that the first of these groups is most likely to include the stem cell population and that Nanos3 may function in transit amplifying cells.  相似文献   

12.
The population structure of olive flounder Paralichthys olivaceus was estimated using nine polymorphic microsatellite (MS) loci in 459 individuals collected from eight populations, including five wild and three hatchery populations in Korea. Genetic variation in hatchery (mean number of alleles per locus, A = 10·2–12·1; allelic richness, AR = 9·3–10·1; observed heterozygosity, HO = 0·766–0·805) and wild (mean number of alleles per locus, A = 11·8–19·6; allelic richness, AR = 10·9–16·1; observed heterozygosity, HO = 0·820–0·888) samples did not differ significantly, suggesting a sufficient level of genetic variation in these well‐managed hatchery populations, which have not lost a substantial amount of genetic diversity. Neighbour‐joining tree and principal component analyses showed that genetic separation between eastern and pooled western and southern wild populations in Korea was probably influenced by restricted gene flow between regional populations due to the barrier effects of sea currents. The pooled western and southern populations are genetically close, perhaps because larval dispersal may depend on warm currents. One wild population (sample from Wando) was genetically divergent from the main distribution, but it was genetically close to hatchery populations, indicating that the genetic composition of the studied populations may be affected by hydrographic conditions and the release of fish stocks. The estimated genetic population structure and potential applications of MS markers may aid in the proper management of P. olivaceus populations.  相似文献   

13.
The ABO blood group influences susceptibility to severe Plasmodium falciparum malaria. Recent evidence indicates that the protective effect of group O operates by virtue of reduced rosetting of infected red blood cells (iRBCs) with uninfected RBCs. Rosetting is mediated by a subgroup of PfEMP1 adhesins, with RBC binding being assigned to the N-terminal DBL1α1 domain. Here, we identify the ABO blood group as the main receptor for VarO rosetting, with a marked preference for group A over group B, which in turn is preferred to group O RBCs. We show that recombinant NTS-DBL1α1 and NTS-DBL1α1-CIDR1γ reproduce the VarO-iRBC blood group preference and document direct binding to blood group trisaccharides by surface plasmon resonance. More detailed RBC subgroup analysis showed preferred binding to group A1, weaker binding to groups A2 and B, and least binding to groups Ax and O. The 2.8 Å resolution crystal structure of the PfEMP1-VarO Head region, NTS-DBL1α1-CIDR1γ, reveals extensive contacts between the DBL1α1 and CIDR1γ and shows that the NTS-DBL1α1 hinge region is essential for RBC binding. Computer docking of the blood group trisaccharides and subsequent site-directed mutagenesis localized the RBC-binding site to the face opposite to the heparin-binding site of NTS-DBLα1. RBC binding involves residues that are conserved between rosette-forming PfEMP1 adhesins, opening novel opportunities for intervention against severe malaria. By deciphering the structural basis of blood group preferences in rosetting, we provide a link between ABO blood grouppolymorphisms and rosette-forming adhesins, consistent with the selective role of falciparum malaria on human genetic makeup.  相似文献   

14.
Leaf mass per unit area (LMA), carbon and nitrogen contents, leaf construction cost, and photosynthetic capacity (P max) of Adiantum reniforme var. sinensis, an endangered fern endemic to the Three Gorges region in southwest China, were compared in five populations differing in habitat such as soil moisture and irradiance. The low soil moisture and high irradiance habitat population exhibited significantly higher LMA, area-based leaf construction (CCA), and carbon content (CA), but lower leaf nitrogen content per unit dry mass (NM) than the other habitat populations. The high soil moisture and low irradiance habitat populations had the lowest CCA, but their cost/benefic ratios of CCA/P max were similar to the medium soil moisture and irradiance habitat population due to their lower leaf P max. Hence A. reniforme var. sinensis prefers partially shaded, moist but well-drained, slope habitats. Due to human activities, however, its main habitats now are cliffs or steeply sloped bare rocks with poor and thin soil. The relatively high energy requirements and low photosynthetic capacity in these habitats could limit the capability of the species in extending population or interspecific competition and hence increase its endangerment.  相似文献   

15.
Four additional compounds inhibitory to germination of Helminthosporium turcicum spores were isolated from lesion-extracts of field-grown Ht-gene corn (Zea mays) lines which were inoculated with H. turcicum. The compounds were named phytoalexins A3, A4-I, A4-II and A5. A3, A4-1 and A4-1 showed over 99% inhibition of H. turcicum spores at 1 mg/ml of 10% ethanol and LD50 of about 600 μg/ml. A5 showed an LD50 of about 800 μg/ml of 10% ethanol. The ultraviolet, infrared, nuclear magnetic resonance, electron impact mass spectra and field desorption mass spectra showed that these compounds might be related to the previously described phytoalexins A1 and A2. They seem to have the following functional groups: aromatic ring, hydroxyl and/or phenolic groups, carbonyl groups, probably a carboxylic acid or ester type and a long aliphatic side chain.  相似文献   

16.
Creation of wheat-alien disomic addition lines and localization of desirable genes on alien chromosomes are important for utilization of these genes in genetic improvement of common wheat. In this study, wheat-Agropyron cristatum derivative line 5113 was characterized by genomic in situ hybridization (GISH) and specific-locus amplified fragment sequencing (SLAF-seq), and was demonstrated to be a novel wheat-A. cristatum disomic 6P addition line. Compared with its parent Fukuhokomugi (Fukuho), 5113 displayed multiple elite agronomic traits, including higher uppermost internode/plant height ratio, larger flag leaf, longer spike length, elevated grain number per spike and spikelet number per spike, more kernel number in the middle spikelet, more fertile tiller number per plant, and enhanced resistance to powdery mildew and leaf rust. Genes conferring these elite traits were localized on the A. cristatum 6P chromosome by using SLAF-seq markers and biparental populations (F1, BC1F1 and BC1F2 populations) produced from the crosses between Fukuho and 5113. Taken together, chromosomal localization of these desirable genes will facilitate transferring of high-yield and high-resistance genes from A. cristatum into common wheat, and serve as the foundation for the utilization of 5113 in wheat breeding.  相似文献   

17.
Prostaglandins A1, A2 and 15 Epi-A2 were administered orally to human male volunteers. Prostaglandin A1 and 15 Epi-A2 did not consistently affect gastric acid secretion either in terms of the pH values within individual tests or in respect of comparative control test data. Prostaglandin A2 administration resulted in a transient inhibition of secretion in all 6 subjects tested, with the pH rising above 6 in every case.It is concluded that none of these compounds is likely to have therapeutic application to the peptic ulceration problem.  相似文献   

18.

Background

Lung ischemia-reperfusion (IR) injury leads to significant morbidity and mortality which remains a major obstacle after lung transplantation. However, the role of various subset(s) of lung cell populations in the pathogenesis of lung IR injury and the mechanisms of cellular protection remain to be elucidated. In the present study, we investigated the effects of adenosine A2A receptor (A2AAR) activation on resident lung cells after IR injury using an isolated, buffer-perfused murine lung model.

Methods

To assess the protective effects of A2AAR activation, three groups of C57BL/6J mice were studied: a sham group (perfused for 2 hr with no ischemia), an IR group (1 hr ischemia + 1 hr reperfusion) and an IR+ATL313 group where ATL313, a specific A2AAR agonist, was included in the reperfusion buffer after ischemia. Lung injury parameters and pulmonary function studies were also performed after IR injury in A2AAR knockout mice, with or without ATL313 pretreatment. Lung function was assessed using a buffer-perfused isolated lung system. Lung injury was measured by assessing lung edema, vascular permeability, cytokine/chemokine activation and myeloperoxidase levels in the bronchoalveolar fluid.

Results

After IR, lungs from C57BL/6J wild-type mice displayed significant dysfunction (increased airway resistance, pulmonary artery pressure and decreased pulmonary compliance) and significant injury (increased vascular permeability and edema). Lung injury and dysfunction after IR were significantly attenuated by ATL313 treatment. Significant induction of TNF-α, KC (CXCL1), MIP-2 (CXCL2) and RANTES (CCL5) occurred after IR which was also attenuated by ATL313 treatment. Lungs from A2AAR knockout mice also displayed significant dysfunction, injury and cytokine/chemokine production after IR, but ATL313 had no effect in these mice.

Conclusion

Specific activation of A2AARs provides potent protection against lung IR injury via attenuation of inflammation. This protection occurs in the absence of circulating blood thereby indicating a protective role of A2AAR activation on resident lung cells such as alveolar macrophages. Specific A2AAR activation may be a promising therapeutic target for the prevention or treatment of pulmonary graft dysfunction in transplant patients.  相似文献   

19.
Total non-acid glycolipid fractions and total sodium dodecylsulphate (SDS) solubilized protein fractions were isolated from human thrombocytes obtained from single human donors having different blood group A1/A2 phenotypes. The blood group A glycolipid antigens were characterized by immunostaining of thin layer plates with different monoclonal anti-A antibodies. The glycoproteins carrying blood group A epitopes were identified by SDS-PAGE and Western blot analysis using a monoclonal anti-A antibody. Blood group A glycolipid antigens were found in both A1 and A2 thrombocytes but the A2 individuals expressed at least ten times less A glycolipids compared to the A1 individuals. Expression of A type 3/4 chain and small amounts of A type 1 chain glycolipids were seen in thrombocytes of both A1 and A2 individuals, while the type 2 chain A glycolipids appeared to be missing from the A2 thrombocytes. Blood group A reactive glycoproteins were only found in thrombocytes of A1 individuals and could not be detected in A2 individuals or a blood group O individual. The major blood group A glycoprotein were found as a double band migrating in the 130 kDa region.Abbreviations SDS sodium dodecyl sulfate - PAGE polyacrylamide gel electrophoresis - HPTLC high performance thin layer chromatography - CBB Coomassie brilliant blue - GVH graft versus host Part of this work was presented at the Xth International Symposium on Glycoconjugates, Jerusalem, Israel. September, 1989.In the short hand designation for glycolipids, the letter indicate blood group determinant, the first numeral, the number of sugar residues, and the second numeral, the type of carbohydrate chain. Thus, A-6-1 means a hexaglycosylceramide with a blood group A determinant based on the type 1 carbohydrate chain.  相似文献   

20.
The Korean black scraper, Thamnaconus modestus, is one of the most economically important maricultural fish species in Korea. However, the annual catch of this fish has been continuously declining over the past several decades. In this study, the genetic diversity and relationships among four wild populations and two hatchery stocks of Korean black scraper were assessed based on 16 microsatellite (MS) markers. A total of 319 different alleles were detected over all loci with an average of 19.94 alleles per locus. The hatchery stocks [mean number of alleles (N A) = 12, allelic richness (A R) = 12, expected heterozygosity (He) = 0.834] showed a slight reduction (P > 0.05) in genetic variability in comparison with wild populations (mean N A = 13.86, A R = 12.35, He = 0.844), suggesting a sufficient level of genetic variation in the hatchery populations. Similarly low levels of inbreeding and significant Hardy–Weinberg equilibrium deviations were detected in both wild and hatchery populations. The genetic subdivision among all six populations was low but significant (overall F ST = 0.008, P < 0.01). Pairwise F ST, a phylogenetic tree, and multidimensional scaling analysis suggested the existence of three geographically structured populations based on different sea basin origins, although the isolation-by-distance model was rejected. This result was corroborated by an analysis of molecular variance. This genetic differentiation may result from the co-effects of various factors, such as historical dispersal, local environment and ocean currents. These three geographical groups can be considered as independent management units. Our results show that MS markers may be suitable not only for the genetic monitoring of hatchery stocks but also for revealing the population structure of Korean black scraper populations. These results will provide critical information for breeding programs, the management of cultured stocks and the conservation of this species.  相似文献   

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