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A 25-year-old previously asymptomatic pregnant woman at 36 weeks'' gestation was noticed to have repetitive monomorphic ventricular tachycardia. A dilated left ventricle with moderately reduced systolic function was found on echocardiographic examination. This is a very rare presentation of peripartum cardiomyopathy (PPCMP) presenting with repetitive monomorphic ventricular tachycardia.  相似文献   
3.
Host genetic factors are known to determine disease susceptibility in dengue virus infection. Therefore, in this study association of gene polymorphisms of Vitamin D Receptor [rs731236 (Taq) and rs7975232 (Apa1)], Toll-like receptor 2 [rs5743708 (Arg735Gln) and rs5743704 (Pro631His)] and Toll-like receptor 4 [rs4986790A/G(Asp299Gly13843) and rs4986791 C/T(Thr399Ile)] were studied in cases with dengue as compared to controls. Total 98 cases of confirmed dengue virus infection and 98 age, sex and geographically matched healthy controls were enrolled and their genetic polymorphisms for the above mentioned regions were studied by Sanger sequencing. Mutant genotypes CC of VDR rs731236 (Taq1) [(OR 3.808, p value =0.02, CI 1.160-12.498)], GG of VDR rs7975232 (Apa1) [(OR 3.485, p value =0.02, CI 1.162-10.45)] and heterozygous genotypes of TLR4 rs4986790 A/G Asp299Gly [OR 2.40, p value= 0.02, CI 1.12-5.14], TLR4 rs4986791 C/T Thr399Ile [OR 2.09, p value=0.02, CI 1.12-5.14] were found to be significantly more in cases with dengue virus infection as compared to the controls. Also, at these positions mutant alleles were observed in significantly higher number of cases than controls. The values for C allele at VDR rs731236 (Taq1) were OR 1.86, p value 0.009, CI 1.162-3.001; for allele G at rs7975232( Apa1) were OR 2.71, p value 0.006, CI 1.196-2.98 for allele G at TLR4s rs4986790 A/G Asp299Gly were OR 2.35, p value 0.009, CI 1.23-4.50 and for allele T at rs4986791 C/T Thr399Ile were OR 2.36, p value=0.006, CI 1.28-4.38. VDR and TLR4 but not TLR2 gene polymorphisms were found to be associated with dengue susceptibility in Indian population.  相似文献   
4.
For the transfer of genes from B. tournefortii (TT) to the allotetraploid oilseed brassicas, B. juncea AABB, B. carinata BBCC and B. napus AACC, B. tournefortii was first crossed with the three basic diploid species, B. campestris (AA), B. nigra (BE) and B. oleracea (CC), to produce the allodiploids TA, TB and TC. These were tetraploidized by colchicine treatment to produce the allotetraploids TTAA, TTBB and TTCC, which were further crossed with B. juncea and B. napus to produce three-genome hybrids with substitution-type genomic configurations: TACC, TBAA and TCAA. These hybrids along with another hybrid TCBB produced earlier, the three allodiploids, their allotetraploids and the four diploid parent species were studied for their male meiotic behaviour. The diploid parent and the allotetraploids (TTAA, TTBB and TTCC) showed regular meiosis although the pollen viability was generally low in the allotetraploids. In the allodiploids (TA, TB and TC) only some end-to-end associations were observed without any clearly discernible chiasmata or exchange points. Chromosomes involved in end-to-end associations were randomly distributed at the metaphase/anaphase-I stages. In contrast, the three-genome hybrids (TACC, TBAA, TCAA and TCBB) showed normal bivalents whose number exceeded the expected bivalent values. Bivalents arising out of homoeologous pairing were indistinguishable from normal pairs by their disjunction pattern but could be distinguished on the basis of the heteromorphy of the homoeologous chromosomes. The three-genome hybrids could be backcrossed to allotetraploid oilseed brassicas as they had some fertility. In contrast, the allodiploids could neither be selfed nor back-crossed. On the basis of their meiotic stability, in terms of more pronounced homoeologous pairing and fertility for backcrossing, the three-genome configurations provide the best possible situation for the introgression of alien genes from the secondary gene pool to the allotetraploid oilseed crops B. juncea, B. napus and B. carinata.  相似文献   
5.
1. This study introduces delayed fluorescence (DF) excitation spectroscopy as an on‐line tool for in situ monitoring of the composition and biomass of various colour classes of phytoplankton when they are photosynthetically active (cyanobacteria, chlorophytes, chromophytes and cryptophytes). The DF data are validated by comparison with those from conventional methods (weekly microscopic counts and the measurement of chlorophyll concentration). 2. The composition of phytoplankton as assessed by DF agreed reasonably well with the results from microscopic counts, particularly when differences in chlorophyll‐specific DF integrals of the various colour classes were taken into account. 3. Integrals of DF spectra were converted into concentration of chlorophyll a using empirical factors derived from field data. The value of the conversion factor was nearly twice as high when the relative abundance of cyanobacteria was low (<15%) than when it was high. The converted DF‐chl time series agreed well with chlorophyll measurements particularly when blooms were developing. As the DF method is inherently free of the interference caused by pigment degradation products, the discrepancy between the two data sets increased during the collapse of blooms and when sediment resuspension was intense. 4. Fourier spectrum analysis of the time series of DF‐chl indicated that samples must be taken, at a minimum, every 2–3 days to capture the dynamics of phytoplankton. As a consequence, the dynamics of various algal blooms, including their timing, duration and net growth rate, could be estimated with greater confidence than by using conventional methods alone. 5. On‐line DF spectroscopy is an advanced technique for monitoring daily the biomass and composition of the photosynthetically active phytoplankton in aquatic environments, including turbid shallow lakes. At present, the detection limit is around 1 mg DF‐chl a m?3 in terms of total biomass but confidence in estimates of phytoplankton composition declines sharply below about 5 mg chl a m?3. 6. On‐line DF spectroscopy represents a promising approach for monitoring phytoplankton. It will be useful in water management where it can act as an early‐warning system of declines in water quality. In basic ecological research it can supplement manual methods. While default calibration spectra may be acceptable for routine monitoring, we suggest a careful individual calibration of the DF spectrometer for basic research. The statistical methods developed here help to assess the adequacy of various calibration sets.  相似文献   
6.
According to several epidemiological and clinical studies, the concentration of C-reactive protein (CRP) in blood is associated with the risk of coronary heart disease (CHD). However, these studies are limited in high incidence and prevalence area of North-West India. The present case control study investigated the contribution of three relevant CRP single nucleotide polymorphisms: ?717A>G located in the promoter region (rs2794521), +1059G>C on exon2 (rs1800947) and +1444C>T in the 3′ UTR (rs1130864) in 180 angiographically verified CHD cases and 175 control subjects. Minor allele frequencies (G, C and T) of rs2794521, rs1800947 and rs1130864 are observed to be 21.1, 11.7, 29.4 and 11.4, 10.0, 19.7 % in CHD cases and controls respectively. AA genotype of ?717A>G and TT genotype of +1444C>T were significantly associated (P = 0.02 & 0.03 respectively) with the risk of CHD whereas, +1059G and +1444T were found to be strongly related (P = 0.023 & P = 0.008 respectively) with multivariable adjusted CRP levels. AGT Haplotype was significantly associated with the adjusted CRP levels (P < 0.05). Disease association analysis revealed that haplotype AGT influences CHD risk (OR 2.4, 95 % CI 1.23–4.84, P = 0.006) which exacerbates after correcting the confounding effects of risk variables (OR 2.5, 95 % CI 1.27–4.99, P = 0.004). With the global index of Akaike information criterion, it has been observed that the carrying each single unit of this susceptibility haplotype increases CHD risk by a value of 2.41 ± 0.439 (β ± SE) in the recessive mode.  相似文献   
7.
In the present study, anaerobic fungi were isolated from different ruminants and non-ruminants; i.e., cattle, buffalo, sheep, goats, wild bluebulls, elephants, deer, and zebras; and were identified as Anaeromyces, Orpinomyces, Caecomyces, Piromyces, and Neocallimastix sp., based on their morphological characteristics. These isolates possessed significant in vitro hydrolytic enzyme activities; however, an isolate of Caecomyces sp. from elephant was found to exhibit maximum activity, i.e., filter paper cellulase (Fpase; 21.4 mIU/ml), carboxymethyl cellulose (CMCase; 15.1 mIU/ml), cellobiase (37.4 mIU/ml), and xylanase (26.0 mIU/ml). Besides, this isolate also showed the significantly highest ability to digest plant cell-wall contents in vitro. The in vitro dry matter digestibility increased from 45.1 to 48.9% after 48 h of incubation, and the plant cell-wall contents, in terms of neutral detergent fiber and acid detergent fiber, decreased from 64.2 to 61.3% and from 31.3 to 29.6%, respectively. These results indicate that such fibrolytic ruminal fungal strains are prevalent in wild herbivores such as elephants, as well as in other ruminants and non-ruminants, and could be exploited as microbial feed additives for improved nutrition and productivity in domesticated ruminants.  相似文献   
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Eight of 104 fast-growing strains of Rhizobium sp. ( Sesbania ) tested possessed a hydrogen recycling system. Depression of uptake hydrogenase occurred in poor as well as in rich carbon media. A statistically significant increase (> 22%) in total plant nitrogen content and dry matter yield was observed by the inoculation of hup + strains over hup - strains.  相似文献   
10.
Understanding of the functions of microRNAs in breast cancer and breast cancer stem cells have been a hope for the development of new molecular targeted therapies. Here, it is aimed to investigate the differences in the expression levels of let-7a, miR-10b, miR-21, miR-125b, miR-145, miR-155, miR-200c, miR-221, miR-222 and miR-335, which associated with gene and proteins in MCF-7 (parental) and MCF-7s (Mammosphere/stem cell-enriched population/CD44+/CD24-cells) cells treated with paclitaxel. MCF-7s were obtained from parental MCF-7 cells. Cytotoxic activity of paclitaxel was determined by ATP assay. Total RNA isolation and cDNA conversion were performed from the samples. Changes in expression levels of miRNAs were examined by RT-qPCR. Identified target genes and proteins of miRNAs were analyzed with RT-qPCR and western blot analysis, respectively. miR-125b was significantly expressed (2.0946-fold; p = 0.021) in MCF-7s cells compared to control after treatment with paclitaxel. Downregulation of SMO, STAT3, NANOG, OCT4, SOX2, ERBB2 and ERBB3 and upregulation of TP53 genes were significant after 48 h treatment in MCF-7s cells. Protein expressions of SOX2, OCT4, SMAD4, SOX2 and OCT4 also decreased. Paclitaxel induces miR-125b expression in MCF-7s cells. Upregulation of miR-125b may be used as a biomarker for the prediction of response to paclitaxel treatment in breast cancer.  相似文献   
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