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71.
Hepatitis C is one of the common types of chronic liver disease, and its plausible association with trace metal imbalance has been investigated in the present study. The blood samples of hepatitis C patients and healthy donors were analysed for trace metals (Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Pb, and Zn) by flame atomic absorption spectrophotometry after wet acid digestion. In the blood of the hepatitis patients, mean concentrations of essential metals, Na, K, Fe, Ca, Mg, and Zn, were 918.7, 361.0, 102.5, 20.00, 24.66, and 9.429 ppm, respectively, while the mean metal levels in the blood of healthy donors were 1509, 406.8, 232.5, 28.35, 24.59, and 8.799 ppm, respectively. On the average, Cr was significantly higher, while Na, Fe, Ca, Cu, Mn, Pb, and Cd were comparatively lower in the blood of the patients. The correlation study manifested significantly divergent mutual relationships of trace metals in the blood of the patients and healthy donors. Multivariate statistical methods revealed considerably diverse distribution of trace metals in the two groups. Dissimilarity in the trace metal distribution was also noted with the gender and residential location of the donors in both groups.  相似文献   
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To decrease the polyhydroxyalkanoate (PHA) production cost by supplying renewable carbon sources has been an important aspect in terms of commercializing this biodegradable polymer. The production of biodegradable poly(3-hydroxyalkanoates) (PHA) from raw potato starch by the Bacillus cereus 64-INS strain isolated from domestic sludge has been studied in a lab-scale fermenter. The bacterium was screened for the degradation of raw potato starch by a starch hydrolysis method and for PHA production by Nile blue A and Sudan black B staining. Shake-flask cultures of the bacterium with glucose [2% (w/v)] or raw potato starch [2% (w/v)] produced PHA of 64.35% and 34.68% of dry cell weight (DCW), respectively. PHA production was also carried out in a 5-L fermenter under control conditions that produced 2.78 g/L of PHA and PHA content of 60.53% after 21 hr of fermentation using potato starch as the sole carbon source. Gas chromatography–mass spectroscopy (GC-MS) analyses confirmed that the extracted PHA contained poly(3-hydroxybutyrate) (PHB) as its major constituent (>99.99%) irrespective of the carbon source used. The article describes, for what we believe to be the first time, PHB production being carried out without any enzymatic or chemical treatment of potato starch at higher levels by fermentation. More work is required to optimize the PHB yield with respect to starch feeding strategies.  相似文献   
74.

Background

Cryptococcus neoformans, a basidiomycetous fungus of universal occurrence, is a significant opportunistic human pathogen causing meningitis. Owing to an increase in the number of immunosuppressed individuals along with emergence of drug-resistant strains, C. neoformans is gaining importance as a pathogen. Although, whole genome sequencing of three varieties of C. neoformans has been completed recently, no global proteomic studies have yet been reported.

Results

We performed a comprehensive proteomic analysis of C. neoformans var. grubii (Serotype A), which is the most virulent variety, in order to provide protein-level evidence for computationally predicted gene models and to refine the existing annotations. We confirmed the protein-coding potential of 3,674 genes from a total of 6,980 predicted protein-coding genes. We also identified 4 novel genes and corrected 104 predicted gene models. In addition, our studies led to the correction of translational start site, splice junctions and reading frame used for translation in a number of proteins. Finally, we validated a subset of our novel findings by RT-PCR and sequencing.

Conclusions

Proteogenomic investigation described here facilitated the validation and refinement of computationally derived gene models in the intron-rich genome of C. neoformans, an important fungal pathogen in humans.  相似文献   
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The present study documents the isolation of eight polymorphic microsatellite markers from the bighead catfish, Clarias macrocephalus and cross-amplification in two other catfish species. The number of alleles per locus in C. macrocephalus ranged from 2 to 21. The most polymorphic locus was NCm-G12 with 21 alleles while the least polymorphic locus was NCm-H2 with only two alleles. Locus NCm-F8 significantly deviated from Hardy–Weinberg equilibrium (P value <0.05) after Bonferroni correction. Linkage disequilibrium was non-significant in all loci comparisons. The observed and expected heterozygosities varied from 0.033 to 0.967 and from 0.033 to 0.942, respectively. Mean polymorphic information content for the eight loci was 0.765. Cross-amplification was successfully performed with two other catfish species, C. batrachus and C. meladerma for all eight loci. Locus NCm-D8 was monomorphic in both species while NCm-F8 was monomorphic only in C. batrachus. These newly developed markers would be useful for better management and conservation of the economically important C. macrocephalus species.  相似文献   
77.
In the present cross sectional study, we aimed to ascertain the relative associations of GST genotypes with GST activity variations and also with the risk to DMT2 predisposition among men and women separately. Clinical samples obtained from 244 DMT2 cases (120 Males and 124 Females) and 228 controls (117 Males and 111 Females) belonging to Asian Indian ethnicity were used to test for glycemic index, lipid profile, GST activity and GST genotypes. The frequencies of single and combinations of GST genotypes were statistically examined for their association with DMT2 risk among both study groups. The GST activity is significantly lowered in DMT2 group compared to controls (p = < 0.001). This reduction is found to be subjective to single and combinations of GST genotypes among diabetic patients. The frequency distribution for single, double and triple combinations of genotypes of GSTT1, GSTM1 and GSTP1 showed the varying degrees of association with DMT2 risk from 0.5 to 5.6-fold among male and female patients (for all associations, p value was <0.05). Interestingly, GST activity was lowered in both male and female patients with single or combinational genotypes of GSTM1 (Null), GSTT1 (Null), and P1 (V/V) (for all associations, p value was = <0.0001). The reduced anti-oxidant capacity among diabetic patients with certain GST genotypes may have some important implications for disease diagnosis and therapy.  相似文献   
78.
Integration of the priming effect (PE) in ecosystem models is crucial to better predict the consequences of global change on ecosystem carbon (C) dynamics and its feedbacks on climate. Over the last decade, many attempts have been made to model PE in soil. However, PE has not yet been incorporated into any ecosystem models. Here, we build plant/soil models to explore how PE and microbial diversity influence soil/plant interactions and ecosystem C and nitrogen (N) dynamics in response to global change (elevated CO2 and atmospheric N depositions). Our results show that plant persistence, soil organic matter (SOM) accumulation, and low N leaching in undisturbed ecosystems relies on a fine adjustment of microbial N mineralization to plant N uptake. This adjustment can be modeled in the SYMPHONY model by considering the destruction of SOM through PE, and the interactions between two microbial functional groups: SOM decomposers and SOM builders. After estimation of parameters, SYMPHONY provided realistic predictions on forage production, soil C storage and N leaching for a permanent grassland. Consistent with recent observations, SYMPHONY predicted a CO2‐induced modification of soil microbial communities leading to an intensification of SOM mineralization and a decrease in the soil C stock. SYMPHONY also indicated that atmospheric N deposition may promote SOM accumulation via changes in the structure and metabolic activities of microbial communities. Collectively, these results suggest that the PE and functional role of microbial diversity may be incorporated in ecosystem models with a few additional parameters, improving accuracy of predictions.  相似文献   
79.
Among ladybirds, diapause has evidently been most studied in Coccinella septempunctata L. adults. Coccinella septempunctata (C‐7), the seven spot, has attracted attention both in Europe and the USA for being heterogeneous as to the induction of diapause. A polyphenic character of diapause is a prominent feature in C. septempunctata and this phenomenon generally and often generates voltinism heterogeneity within populations. A greater part of the C‐7 population shows an obligatory univoltine cycle, whereas a smaller proportion is facultatively polyvoltine. Coccinella s. bruckii in Japan is bivoltine, in which the first generation of adults aestivate while the second generation hibernates. This paper reviews this heterodynamic cycle and its importance in the life history of C‐7, as reported from different regions of the world. Heterogeneous voltinism and diapause smooth the progress of a portion of C‐7 populations to take benefit of aphids well into late summer and autumn. Understanding such variation and plasticity in the life history of this species can help in organizing proper biological control attempts using it as a biocontrol agent.  相似文献   
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