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91.
Hereditary hemochromatosis and alpha-1antitrypsin deficiency are genetic diseases characterized by endoplasmic reticulum (ER) stress with subsequent development of liver disease. Our aim was to estimate the frequency of hemochromatosis gene (HFE) mutant alleles (C282Y and H63D) and alpha-1 antitrypsin S/Z variants among Egyptian HCV cirrhotic patients and in hepatocellular carcinoma patients and to evaluate their effects on disease progression. HFE and alpha-1 antitrypsin polymorphisms were characterized in 200 Egyptian patients with HCV infection (100 patients complicated with cirrhosis, 100 patients with HCC) and 100 healthy subjects who had no history of any malignancy. The frequencies of HD genotype of H63D mutation were significantly increased in HCC patients compared to control group and to cirrhosis group. Also, the frequencies of DD genotype were significantly increased In HCC group compared to control group and to cirrhosis group. Our results suggested that Carriers of the D allele of H63D mutation were significantly more likely to develop HCC. 相似文献
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Two semi-arid tropical grasslands, one of an alfisol and the other on vertisol were sampled for earthworm populations during July 1985 to July 1987. The soil of the alfisol grassland was slightly acidic while that of the vertisol was slightly alkaline. The alfisol grassland has a lower range of soil moisture, soil temperature, electrical conductivity, organic carbon, available nitrogen and potassium, and a higher range of phosphorus compared to the vertisol. The alfisol grassland was inhabited byOctochaetona phillotti (Michaelsen) with rare occurrence ofBarogaster annandalei (Stephenson) whereas the vertisol grassland was inhabited only byB. annandalei. The total population ofO. phillotti ranged between 16 and 96/m2 while its juvenile population ranged between 3.2 and 25.6/m2, pre-adult population between 5.3 and 53.6/m2 and adult population between 0 and 28.8/m2. The total population ofB. annandalei ranged between 3.2 and 58.3/m2 and its juvenile population between 0 and 26.6/m2, pre-adult population 0 and 10.6/m2 and adult population between 0 and 22.4/m2. The earthworms migrated to deeper layers during winter and summer,O. phillotti reaching a maximum depth of 40 cm andB. annandalei reaching a depth of 45 cm, and seen in quiescent stage. Their seasonal population structure was significantly influenced by the seasonal patterns in rainfall, soil temperature, pH, electrical conductivity and phosphorus. These variables along with organic carbon, available nitrogen and potassium together accounted for 32–63% and 79–91% respectively, of the variation in seasonal population fluctuation of differentO. phillotti andB. annandalei age groups. The physical factors of the soil were collectively more effective in causing the seasonal variation in their population size than the chemical factors.Visiting scientist (under the Rockefeller Foundation Environmental Research Fellowship in International Agriculture) in Resource Management Programme of ICRISAT, Andhra Pradesh, India 相似文献
95.
Pre-eclampsia, a life-threatening disease during pregnancy, is a leading cause of global maternal mortality. Although there is substantial evidence of a genetic background, the complexity of the processes involved and nature of the maternal-fetal phenomenon do not make the search for the causative genes easy. Recent retrospective studies on the subject suggest the heritable allelic variations, particularly the utero-placental renin-angiotensin system with defective placental vascular development, could become the cornerstone for the genetics of pre-eclampsia and hence might well be associated with such defective development. Moreover, the role of immune mechanisms (immune maladaptation) deserves not to be ignored. Large-scale studies entailing genomewide scanning, sib-pair linkage analysis, and family-based association studies with appropriate power to detect genes with a lower relative risk are necessary to understand the puzzle of the disease. Moreover, recently, the importance of epigenetic features and the effect of imprinted genes related to trophoblast growth as well as fetal development on hypertension in pregnancy have been highlighted. All these possibilities are intuitively attractive and are supported by some circumstantial evidence. Although the consistent tenor of a series of papers instill some confidence, we need meticulously designed larger-scale investigations including large numbers of affected women and their babies to provide the analytic stringency essential to study the polygenic multifactorial basis of pre-eclampsia. 相似文献
96.
T. N. E. Gray R. Crouthers K. Ramesh J. Vattakaven J. Borah M. K. S. Pasha T. Lim C. Phan R. Singh B. Long S. Chapman O. Keo M. Baltzer 《Biodiversity and Conservation》2017,26(10):2383-2399
Reintroduction is a viable conservation strategy for large carnivores however such reintroductions require robust feasibility assessments, considering ecological, management, and social factors, prior to implementation. Plans are being developed in a number of tiger range countries, including Cambodia, for tiger Panthera tigris reintroductions in response to local and national extinctions. We provide a framework for undertaking feasibility assessments for tiger, and other large carnivore, reintroductions and present a number of methodological tools, and appropriate indicators, for conducting such assessments. We apply the framework to plans by the Royal Government of Cambodia for tiger reintroduction into Srepok Wildlife Sanctuary (formally Mondulkiri Protected Forest), eastern Cambodia. Srepok Wildlife Sanctuary forms part of a large (>13,000-km2) trans-boundary conservation landscape with potential to support a tiger source population. Current ungulate prey densities, assessed through robust line-transect sampling, at approximately 5.0 individuals per km2 may be sufficient to support a breeding tiger population. However levels of protected area management and law enforcement fall below global standards for tiger recovery. Local communities, though supportive of conservation efforts, also identified a number of concerns regarding reintroduction. Therefore current ecological, social, and management conditions within SWS are not currently suitable for tiger reintroduction. However with improved and more effective law enforcement, combined with robust monitoring of the indicators within our framework, such conditions could be met. We recommend that our framework for assessing landscape suitability for reintroductions offers an effective road map for reintroduction-based recovery of tiger populations across tiger range countries. 相似文献
97.
Chimeric peptide of Met-enkephalin and FMRFa (YGGFMKKKFMRFa-YFa), a κ-opioid receptor specific peptide, did not induce tolerance and cross-tolerance effects to its analgesic action on day 5 after pretreatment with either YFa or morphine for 4 days. However, pretreatment with YFa for 4 days led to the development of cross-tolerance to the analgesic effects of morphine and also 4 days of pretreatment of morphine resulted in the expression of tolerance to its own analgesic effects. Similar expression of tolerance and cross-tolerance were also observed when YFa was compared with the κ receptor agonist peptide dynorphin A(1–13) [DynA(1–13)]. Cross-tolerance effects between YFa and DynA(1–13) analgesia were also not observed on day 5. Interestingly, when YFa and DynA(1–13) were tested for their analgesic effects for 5 days, reduction in analgesia on day 3 was observed in case of DynA(1–13) whereas YFa maintained its analgesia for 5 days. Thus, chimeric peptide YFa may serve as a useful probe to understand pain modulation and expression of tolerance and cross-tolerance behavior with other opioids. 相似文献
98.
Allelic variation in the cg2 gene does not correlate with chloroquine resistance among Indian Plasmodium falciparum isolates. 总被引:1,自引:0,他引:1
Indu Sharma Manish K. Aneja Sukla Biswas Vas Dev Musharraf A. Ansari S. Tazeen Pasha Yagya D. Sharma 《International journal for parasitology》2001,31(14):1669-1672
The cg2 gene of Plasmodium falciparum has been proposed to be associated with chloroquine resistance. Here we describe PCR amplification and sequencing of all the four repeat regions (kappa (κ), gamma (γ), psi (φ) and omega (ω)) of this gene, from Indian isolates. There were variant forms for each of these repeat regions (two for κ and γ, and three for φ and ω) among the 123 Indian isolates of P. falciparum. Among these isolates certain forms of φ and ω repeats were uniquely present while some of the reported forms of the κ and ω repeats were absent. The pattern of combination of all four repeat regions of cg2 gene (genotype) was analysed from 52 isolates. A total of 11 different genotypes were observed among these cases, of which 10 were unique to Indian isolates. Certain genotypes were more common than others. The nucleotide sequencing of all the four repeat regions revealed that Indian isolates have some unique repeating units within the γ and ω domains. Altogether, the PCR and sequencing results showed that there was an unrelatedness between cg2 repeats and chloroquine resistance. 相似文献
99.
Bisht V Arora N Singh BP Pasha S Gaur SN Sridhara S 《FEMS immunology and medical microbiology》2004,42(2):205-211
Epicoccum purpurascens (EP) is a ubiquitous saprophytic mould, the inhalant spores and mycelia of which are responsible for respiratory allergic disorders in 5-7% of population worldwide. The diagnosis/therapy of these disorders caused by fungi involves the use of standardized and purified fungal extracts. A 33.5 kDa glycoprotein, Epi p 1 released histamine from whole blood cells of EP allergic patients at a concentration of 50-ng protein. The high specific IgE values detected in EP hypersensitive sera indicated that Epi p 1 is capable of mediating type I hypersensitive reaction in predisposed individuals. It also showed protease activity by virtue of its dose dependent cleavage of serine protease specific synthetic substrate, N-benzoyl arginine ethyl ester hydrochloride (BAEE). The serine protease nature of Epi p 1 was confirmed by its N-terminal sequence (ADG/FIVAVELD/STY) homology to a subtilisin like serine protease. The protease activity of Epi p 1 may be responsible for making its way into the system of pre-disposed individuals through epithelial cell detachment and the histamine releasing ability by cross-linking of IgE antibodies on cell surface is the cause of its allergenic nature. 相似文献
100.