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81.
Regucalcin (RGN) is a calcium‐regulating, anti‐apoptotic, antioxidative and antiproliferative multifunctional protein predominantly seen in liver and kidney. All these functions are very crucial during spermatogenesis and sperm maturation process until fertilization of the ovum. Although many studies have reported the wide distribution of regucalcin in the male reproductive tract of the rat, human and bovine, its presence in spermatozoa is yet to be demonstrated wherein calcium has a pivotal role in the transport, capacitation, acrosomal reaction and further fusion with ova. Here, we detected the expression of regucalcin mRNA and protein in buffalo spermatozoa using real‐time PCR and Western blot, respectively. The study detected two new regucalcin isoforms of 44 kDa and 48 kDa size along with the reported 34‐kDa, 28‐kDa and 24‐kDa isoforms, wherein the 34‐kDa isoform was found to be membrane associated in spermatozoa. Further, immunocytochemistry study localized the regucalcin protein in the acrosomal region of the caudal and ejaculated buffalo spermatozoa while it was detected in both cytoplasm and acrosomal region of testicular spermatozoa. This discovery of RGN in spermatozoa and localization in the acrosomal region will help to focus researchers to see its role in calcium‐related functions like capacitation, acrosomal reaction and membrane fusion. Overall, regucalcin may be a new fertility marker in buffalo and can be utilized for infertility treatments.  相似文献   
82.
Mycoplasma gallisepticum, a major pathogen of chickens and turkeys, has caused significant declines in house finch (Carpodacus mexicanus) populations in the eastern United States since it was first observed in this species in 1994. There is evidence that M. gallisepticum infection is now endemic among eastern house finches, although disease prevalence has declined, suggesting an evolving host-parasite relationship. Studies based on randomly amplified polymorphic DNA (RAPD) have documented the presence of a single, unique RAPD profile in house finch M. gallisepticum isolates, suggesting a single point source of origin, which agrees with the known epidemiologic observations. In the present study, we evaluated the molecular variability of 55 house finch isolates as well as 11 chicken and turkey isolates including reference strains of M. gallisepticum. Molecular variability was evaluated by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis and nucleotide sequencing of the pvpA gene, which encodes for the putative cytadhesin protein PvpA. Three different RFLP groups and 16 genotypes were evident from the 55 house finch isolates evaluated. Sequence analysis of pvpA gene PCR products showed that although most house finch M. gallisepticum isolates clustered more closely to each other, others clustered more closely to either turkey or chicken field isolates. These findings suggest that house finch isolates are more polymorphic than previously recognized by RAPD studies. This feature may allow us to learn more about the molecular evolution and epidemiology of this emerging disease host-parasite relationship.  相似文献   
83.
An increase in vascular permeability was estimated quantitatively in acute inflammatory reaction in the chicken using passive cutaneous anaphylaxis as an experimental model. Dye exuded in the cutaneous lesion was extracted by formamide and measured spectrophotometrically. The technique, though time-consuming, worked well in the chicken. The results suggested that the method can be profitably utilised in studies relating to avian inflammation.  相似文献   
84.
Bader  J. L.  Gonzalez  G.  Goodell  P. C.  Pillai  S. D.  Ali  A. S. 《Water, air, and soil pollution》1999,109(1-4):263-276
Chromium-containing industrial effluents are primarily responsible for environmental contamination by toxic and highly mobile, hexavalent chromium. The dilution plate-count method, using media amended with Cr(VI) at concentrations ranging from 0 to 1000 mg L-1, was used to compare the sizes of Cr(VI)-resistant bacterial populations from a soil contaminated with 25 100 mg kg-1 total Cr [12 400 mg kg-1 Cr(VI)] to those isolated from a slightly contaminated soil (99.6 mg kg-1 total Cr) and two other soils without any history of Cr contamination. Bacterial populations resistant to 500 mg L-1 Cr(VI) were isolated from all soils except the heavily contaminated soil. To determine whether Cr-resistant bacterial populations were indigenous to both the contaminated and the uncontaminated soils, enrichment cultures containing Cr(VI) at concentrations ranging from 0 to 1000 mg L-1 were employed. Bacterial populations, as high as 105 (colony forming units) CFU g-1 soil, tolerant of 500 mg L-1 Cr(VI) were isolated from all soils within 48 h of enrichment suggesting that the presence of aerobic Cr(VI)-resistant bacterial populations is unrelated to contamination levels or contamination history. However, identification of these resistant bacteria using fatty acid profiles was unsuccessful suggesting that these populations may have unique characteristics. Fungal colonies resistant to 1000 mg L-1 Cr(VI) were routinely isolated from both uncontaminated and contaminated soils. The results suggest that Cr-resistant microorganisms may be present in soils, even those with no history of Cr contamination.  相似文献   
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86.
Brackishwater aquaculture is basically farming in coastal region, and it utilizes the saline water from either sea or estuary or creek. Assessment of hydrogeochemisty of groundwater resources in shrimp farming areas is very much required not only for monitoring the shrimp farming impacts, but also to suggest better management strategies for the long-term sustainability of shrimp farming and integrated water resources management in coastal regions. Watershed-based assessment is ideal as watershed is a geohydrological unit, and it will give the realistic and cumulative effects more precisely. With this background, the present investigation was carried out to evaluate the geochemical process regulating groundwater quality in shrimp farming areas of coastal miniwatersheds of Vellar and Coleroon river, Cuddalore district, Tamil Nadu, along the east coast of India. Representative groundwater (29) samples from shallow aquifer (hand pump and open well) were collected periodically (June 2008, January 2009, April 2009 and July 2009) using the simple random sampling method and analyzed for various water quality parameters viz. pH, TDS, total hardness, alkalinity, cations (Ca+, Mg+, Na+) and anions (Cl?, SO4 ?, NO3 ?, HCO3 ?). The groundwater data indicated that the HCO3 was the dominant ion in the study area with sodium (Na > Ca > Mg) and bicarbonate (HCO3 > Cl > SO4) as the predominant cation and anion, respectively. The large variations in mean and standard deviation of ionic concentration suggest that the water chemistry in the study region was not homogenous and may be influenced by complex sources for the hydrogeochemical processes. The piper trilinear diagram depicts the status of the groundwater quality and also suggests that the cation exchange and mineral dissolution was responsible for this elevated ionic composition at some locations in the study area. The multivariate statistical analysis viz., principal component analysis and cluster analysis clearly elucidated that the groundwater quality in the area is mainly due to natural process and the shrimp farming is not an influencing factor.  相似文献   
87.
88.
Ohne Zusammenfassung  相似文献   
89.
90.
The radionuclide concentrations in Periyar river at the industrial zone showed significant reduction, by factors ranging form 3 to 5 during the post-1980 period as compared to pre-1980 due to better effluent treatment practices adopted by industrial units situated on the river bank. The studies revealed that nearly 90% of Po-210 in the river environment was unsupported, showing atmospheric pathway of deposition by decay of Rn-222. The mass and activity (Ra-228) median diameters of sedimented particels of less than 63 µ were 15 ± 2.8 µm and 18 ± 2.5 µm. respectively. The particle size followed log-normal distribution. Depth distribution of Ra-228 in sediment was investigated for its concentration. This nuclide showed highest concentration at depths ranging from 10 to 30 cm. The studies have helped to identify that particles of less than 63 µm present in the sediment layer up to 30 cm were mainly responsible for transport of radionuclides in the river and its estuary.  相似文献   
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