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131.
Twelve fungi namelyAlternaria alternata, Aspergillus flavus, A niger, A ochraceus, Actinomucor repens, Capnodoium spp., Curvularia lunata, Fusarium pallidoroseum, F solani, F verticillioides, Penicillium citrinum and Rhizopus stolonifer were recorded from samples ofAegle marmelos, Aesculus indica, Buchanania lanzan andPinus gerardiana. In case ofPrunus amygdalus only Rstolonifer was recorded. A significant variation in pattern of mycoflora incidence was observed in terms of source and season. Fungal infestation in most of the substrates was found to be highest during monsoon. Aflatoxins were the most common mycotoxins elaborated by different isolates ofA flavus obtained fromA marmelos, B lanzan andP gerardiana. The amount of aflatoxins produced by the toxigenic isolates ofA flavus was in the range of traces to 0.9–26.0 μg/ml inA marmelos, 0.8–17.5 μg/ml inP gerardiana and 0.65–13.2 μg/ml inB lanzan. The percentage toxigenicity was comparatively lower in the isolates of other mycotoxigenic fungi. Aflatoxins were detected almost in all the samples analyzed for mycotoxin contamination. However, traces of zearalenone were detected inA marmelos. The concentration of aflatoxin B1 was in the range of 0.13–0.75 μg/g inA marmelos, 0.09–0.60 μg/g inP gerardiana and 0.01–0.20 ug/g inB lanzan. Mycotoxins were not detected inAesculus indica andPrunus amygdalus.  相似文献   
132.
The role of prolactin as a diabetogenic hormone was based on studies describing the ability of administered prolactin to raise the level of serum glucose. In the present study, female rats were made hyperprolactinemic by the transplantation of two anterior pituitary glands under the renal capsule, obtained from littermate donors. Chronic hyperprolactinemia increased blood glucose and impaired the glycolytic pathway of hepatic carbohydrate metabolism. However, basal serum insulin values were not different from those of controls. These data suggest that chronic hyperprolactinemia has an hyperglycemic effect and has a significant influence on glucose handling by the liver, through reduced glycolysis.  相似文献   
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134.
Chick embryonic cells can be used to develop an easy and economical in vitro model for conducting studies on the disease muscle dystrophy (MD). For this, the limb myoblasts from 11th day chick embryo were isolated and cultured. To this muscle cell culture, anti-dystroglycan antibody (IIH6) was added so as to target the α-dystroglycan and disrupt the connection between the cytoskeletal proteins and the extracellular matrix (which is a characteristic feature of MD). Cells were allowed to differentiate further and the morphometrics and mRNA expression were studied. The IIH6-treated muscle cells displayed changes in morphometry, contractibility, and also atrophy was observed when compared to the control cultures. Concomitant gene expression studies showed an upregulation in TGF-β expression, while the muscle sculpture genes MYOD1, MYF5, LAMA2 and MYOG were downregulated resembling the MD in vivo. This simple and cost-effective method can be useful in studies to further understand the disease mechanism and also in conducting initial studies on effect of novel pharmacological agents.  相似文献   
135.

Background

Although genomic DNA isolation using the Chelex 100 resin is rapid and inexpensive, the DNA obtained by this method has a low concentration in solution and contains suspended impurities. The presence of debris in the DNA solution may result in degradation of DNA on long term storage and inhibition of the polymerase chain reaction. In order to remove impurities and concentrate the DNA in solution, we have introduced modifications in the existing DNA isolation protocol using Chelex-100. We used ammonium acetate to precipitate proteins and a sodium acetate- isopropanol mixture to pellet out DNA which was washed with ethanol.

Results

A pure DNA pellet that can be dissolved in water or Tris-EDTA buffer and stored for a long time at ??80 °C was obtained. We also observed a 20-fold change in the DNA concentration following precipitation and re-dissolution.

Conclusion

Our method is different from other extraction methods since it uses non-toxic, easily available and inexpensive reagents as well as minimal amounts of blood or tissue samples for the DNA extraction process. Besides its use in sex determination and genotyping in lab animals as described in this paper, it may also have applications in forensic science and diagnostics such as the easy detection of pathogenic DNA in blood.
  相似文献   
136.
Sirtuins regulate a variety of cellular processes through protein deacetylation. The best-known member of mammalian sirtuin family, Sirt1, plays important roles in the maintenance of cellular homeostasis by regulating cell metabolism, differentiation and stress responses, among others. Sirt1 activity requires tight regulation to meet specific cellular requirements, which is achieved at different levels and by specific mechanisms. Recently, a regulatory loop between Sirt1 and another sirtuin, Sirt7, was identified. Sirt7 inhibits Sirt1 autodeacetylation at K230 and activation thereby preventing Sirt1-mediated repression of adipocyte differentiation by inhibition of the PPARγ gene. Here, we extend the regulatory complexity of Sirt7-dependent restriction of Sirt1 activity by demonstrating that Sirt7 reduces activation of a previously described prominent Sirt1 target, the histone methyltransferase Suv39h1. We show that removal of the acetyl-group at K230 in Sirt1 due to the absence of Sirt7 leads to hyperactivation of Sirt1 and thereby to constantly increased activity of Suv39h1.  相似文献   
137.
138.
Applied Microbiology and Biotechnology - Foodstuffs and water are the key sources of cadmium biomagnifiaction. The available strategies to mitigate this problem are unproductive and expensive for...  相似文献   
139.
Length‐weight relationships (LWRs) for five indigenous fish species under five genera and two families, namely Cyprinion semiplotum (McClelland, 1839), Barilius barna (Hamilton, 1822), Barilius barila (Hamilton, 1822), Gagata sexualis Tilak, 1970 and Pseudolaguvia shawi (Hora, 1921) were studied from Torsa River in West Bengal, India. Sampling was done at quarterly intervals from November, 2015 to December, 2016 and a total of 701 fish specimens were collected using cast nets (mesh size of 15–20 mm), gill nets (mesh size 20–35 mm) and bamboo traps. In the present study, b value ranges from 2.686 to 3.268. LWRs for these fish species (except P. shawi) have not been reported in FishBase. A new maximum length has been recorded for P. Shawi and G. sexualis. The relative condition factor (Kn) values was found to range from 1.004 to 1.028.  相似文献   
140.
Stevia rebaudiana (S. rebaudiana) is the most important therapeutic plant species and has been accepted as such worldwide. It has a tendency to accumulate steviol glycosides, which are 300 times sweeter than marketable sugar. Recently, diabetic patients commonly use this plant as a sugar substitute for sweet taste. In the present study, the effects of different spectral lights were investigated on biomass accumulation and production of secondary metabolites in adventitious root cultures of S. rebaudiana. For callus development, leaf explants were excised from seed-derived plantlets and inoculated on a Murashige and Skoog (MS) medium containing the combination of 2,4-dichlorophenoxy acetic acid (2, 4-D, 2.0 mg/l) and 6-benzyladenine (BA, 2.0 mg/l), while 0.5 mg/l naphthalene acetic acid (NAA) was used for adventitious root culture. Adventitious root cultures were exposed to different spectral lights (blue, green, violet, red and yellow) for a 30-day period. White light was used as control. The growth kinetics was studied for 30 days with 3-day intervals. In this study, the violet light showed the maximum accumulation of fresh biomass (2.495 g/flask) as compared to control (1.63 g/flask), while red light showed growth inhibition (1.025 g/flask) as compared to control. The blue light enhanced the highest accumulation of phenolic content (TPC; 6.56 mg GAE/g DW), total phenolic production (TPP; 101 mg/flask) as compared to control (5.44 mg GAE/g DW; 82.2 mg GAE/g DW), and exhibited a strong correlation with dry biomass. Blue light also improved the accumulation of total flavonoid content (TFC; 4.33 mg RE/g DW) and total flavonoid production (TFP; 65 mg/flask) as compared to control. The violet light showed the highest DPPH inhibition (79.72%), while the lowest antioxidant activity was observed for control roots (73.81%). Hence, we concluded that the application of spectral lights is an auspicious strategy for the enhancement of the required antioxidant secondary metabolites in adventitious root cultures of S. rebaudiana and of other medicinal plants.  相似文献   
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