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41.
Down syndrome (DS) is one of the commonest disorders with huge medical and social cost. DS is associated with number of phenotypes including congenital heart defects, leukemia, Alzeihmer’s disease, Hirschsprung disease etc. DS individuals are affected by these phenotypes to a variable extent thus understanding the cause of this variation is a key challenge. In the present review article, we emphasize an overview of DS, DS-associated phenotypes diagnosis and management of the disease. The genes or miRNA involved in Down syndrome associated Alzheimer’s disease, congenital heart defects (AVSD), leukemia including AMKL and ALL, hypertension and Hirschprung disease are discussed in this article. Moreover, we have also reviewed various prenatal diagnostic method from karyotyping to rapid molecular methods -  MLPA, FISH, QF-PCR, PSQ, NGS and noninvasive prenatal diagnosis in detail.  相似文献   
42.
Malaria, a leading parasitic killer, is caused by Plasmodium spp. The pathology of the disease starts when Plasmodium merozoites infect erythrocytes to form rings, that matures through a large trophozoite form and develop into schizonts containing multiple merozoites. The number of intra-erythrocytic merozoites is a key-determining factor for multiplication rate of the parasite. Counting of intraerythrocytic merozoites by classical 2-D microscopy method is error prone due to insufficient representation of merozoite in one optical plane of a schizont. Here, we report an alternative 3-D microscopy based automated method for counting of intraerythrocytic merozoites in entire volume of schizont. This method offers a considerable amount of advantages in terms of both, ease and accuracy.  相似文献   
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44.
S. Agarwal, R. Gupta, V. K. Iyer, S. R. Mathur and R. Ray Cytopathological diagnosis of alveolar soft part sarcoma, a rare soft tissue neoplasm Objective: Alveolar soft part sarcoma (ASPS) is a rare soft tissue neoplasm, having various morphological mimics, especially on fine needle aspiration cytology (FNAC). Because no definite immunohistochemical markers are available to aid a correct diagnosis, knowledge of the cytomorphological features is essential for correct patient management. Cytological features of five cases of ASPS are discussed, along with the ultrastructural findings available in one of them. Methods: Cytology records from 1997 to 2009 were reviewed for cases with a diagnosis of ASPS on cytology. The histology slides of the cases were also assessed for confirmation of the diagnosis. All the slides were reviewed by three pathologists. Results: There were five cases of ASPS diagnosed on FNAC. Their cytological features were noted in detail. The diagnoses in all the cases were confirmed on histology, and ultrastructural findings available in one of them were also assessed. Conclusions: The knowledge of cytological features may aid in diagnosing this rare tumour correctly on FNA smears, thus enabling correct patient management.  相似文献   
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46.
The human health hazards related to persisting use of bisphenol-A (BPA) are well documented. BPA-induced neurotoxicity occurs with the generation of oxidative stress, neurodegeneration, and cognitive dysfunctions. However, the cellular and molecular mechanism(s) of the effects of BPA on autophagy and association with oxidative stress and apoptosis are still elusive. We observed that BPA exposure during the early postnatal period enhanced the expression and the levels of autophagy genes/proteins. BPA treatment in the presence of bafilomycin A1 increased the levels of LC3-II and SQSTM1 and also potentiated GFP-LC3 puncta index in GFP-LC3-transfected hippocampal neural stem cell-derived neurons. BPA-induced generation of reactive oxygen species and apoptosis were mitigated by a pharmacological activator of autophagy (rapamycin). Pharmacological (wortmannin and bafilomycin A1) and genetic (beclin siRNA) inhibition of autophagy aggravated BPA neurotoxicity. Activation of autophagy against BPA resulted in intracellular energy sensor AMP kinase (AMPK) activation, increased phosphorylation of raptor and acetyl-CoA carboxylase, and decreased phosphorylation of ULK1 (Ser-757), and silencing of AMPK exacerbated BPA neurotoxicity. Conversely, BPA exposure down-regulated the mammalian target of rapamycin (mTOR) pathway by phosphorylation of raptor as a transient cell''s compensatory mechanism to preserve cellular energy pool. Moreover, silencing of mTOR enhanced autophagy, which further alleviated BPA-induced reactive oxygen species generation and apoptosis. BPA-mediated neurotoxicity also resulted in mitochondrial loss, bioenergetic deficits, and increased PARKIN mitochondrial translocation, suggesting enhanced mitophagy. These results suggest implication of autophagy against BPA-mediated neurodegeneration through involvement of AMPK and mTOR pathways. Hence, autophagy, which arbitrates cell survival and demise during stress conditions, requires further assessment to be established as a biomarker of xenoestrogen exposure.  相似文献   
47.
Male piglets are routinely castrated to eliminate boar taint. However, this treatment is undesirable, and alternative approaches, including genetic strategies to reduce boar taint, are demanded. Androstenone is one of the causative agents of boar taint, and a QTL region affecting this pheromone has previously been reported on SSC5: 22.6–24.8 Mb in Duroc. The QTL region is one of the few reported for androstenone that does not simultaneously affect levels of other sex steroids. The main objective of this study was to fine map this QTL. Whole genome sequence data from 23 Norwegian Duroc boars were analyzed to detect new polymorphisms within the QTL region. A subset of 161 SNPs was genotyped in 834 Duroc sires and analyzed for association with androstenone in adipose tissue and testosterone, estrone sulphate and 17β‐estradiol in blood plasma. Our results revealed 100 SNPs significantly associated with androstenone levels in fat (< 0.001) with 94 of the SNPs being in strong linkage disequilibrium in the region 23.03–24.27 Mb. This haplotype block contains at least four positional candidate genes (HSD17B6, SDR9C7, RDH16 and STAT6) involved in androstenone biosynthesis. No significant associations were found between any of the SNPs and levels of testosterone and estrogens, confirming previous findings. The amount of phenotypic variance explained by single SNPs within the haplotype block was as high as 5.4%. As the SNPs in this region significantly affect levels of androstenone without affecting levels of other sex steroids, they are especially interesting as genetic markers for selection against boar taint.  相似文献   
48.
Mucormycoses are opportunistic fungal infections with a high mortality rate. Rhizopus oryzae is the most common agent implicated in human infections. Although R. homothallicus has been previously reported to be a cause of pulmonary mucormycosis, it is the first time that we are reporting as a causative agent of rhino-orbital and cutaneous mucormycosis.  相似文献   
49.
Plants are confronted with a variety of environmenmtal stresses resulting in enhanced production of ROS. Plants require a threshold level of ROS for vital functions and any change in their concentration alters the entire physiology of plant. Delicate balance of ROS is maintained by an efficient functioning of intriguing indigenous defence system called antioxidant system comprising enzymatic and non enzymatic components. Down regulation of antioxidant system leads to ROS induced oxidative stress causing damage to important cellular structures and hence anomalies in metabolism. Proper mineral nutrition, in addition to other agricultural practices, forms an important part for growth and hence the yield. Potassium (K) is a key macro-element regulating growth and development through alterations in physiological and biochemical attributes. K has been reported to result into accumulation of osmolytes and augmentation of antioxidant components in the plants exposed to water and salt stress. In the present review an effort has been made to revisit the old findings and the current advances in research regarding the role of optimal, suboptimal and deficient K soil status on growth under normal and stressful conditions. Effect of K deficiency and sufficiency is discussed and the information about the K mediated antioxidant regulation and plant response is highlighted.  相似文献   
50.
Root‐nodulating bacteria are intimate associates of legumes. From a pool of rhizobia isolated from root nodules of Mucuna pruriens (Velvet bean/Kaunch), RMP66 and BMP17 were found to be capable of promoting siderophore and IAA production and phosphate solubilization (insoluble tri‐calcium). Both symbionts were studied further to determine their abilities to promote plant growth and to control root‐rot in Mucuna pruriens caused by the pathogenic plant fungus Macrophomina phaseolina. RMP66 and BMP17 were selected based on their excellent inhibitory activities against M. phaseolina (by 78% and 71%, respectively) in dual culture and in agar‐well assays using cell‐free culture filtrate (CFCF) (by 76% and 62%, respectively). Both strains inhibited fungal growth to a greater extent in iron‐deficient medium (51% and 69%) than in iron‐supplemented medium (37% and 0%), respectively. CFCFs of RMP66 and BMP17 obtained from Pikovskaya's broth and tryptophan‐amended YEM broth inhibited fungal growth by 80%‐55% and 70%‐43%, respectively, and were identified as Sinorhizobium meliloti RMP66 and Bradyrhizobium diazoefficiens BMP17 by 16S rDNA sequencing. Centrifuged and pelleted cells harvested from exponentially grown cultures of Smeliloti RMP66 and Bdiazoefficiens BMP17 were used to bacterize seeds of M. pruriens, which then showed enhanced seed germination (by up to 17% and 12%, respectively), and subsequent increases in other plant growth parameters in field trials. Considerable increases in seedling vigour indices (62%: 53% and 110%: 130%) and biomass (8%: 13% and 25%: 28%) were also observed for bacterial treatments. Tn5‐mediated antibiotic‐resistant marker strains showed enhanced nodule occupancy by up to 72% and 68%, respectively. This study describes a multifunctional legume nodule rhizobia that could be utilized in multicropping systems under different agroclimatic conditions as a bioinoculant and alternative to fertilizers.  相似文献   
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