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91.
Arif Mohammad Tanmoy ASM Nawshad Uddin Ahmed Rajesh Arumugam Belal Hossain Mahfuza Marzan Shampa Saha Shams El Arifeen Abdullah H. Baqui Robert E. Black Gagandeep Kang Samir Kumar Saha 《PloS one》2016,11(4)
The World Health Organization (WHO) currently coordinates rotavirus diarrhea and invasive bacterial disease (IBD) surveillance at 178 sentinel sites in 60 countries. However, only 78 sites participate in both surveillance systems using a common sentinel site. Here, we explored the feasibility of extending a WHO-IBD surveillance platform to generate data on the burden of rotaviral diarrhea and its epidemiological characteristics to prepare the countries to measure the impact of rotaviral vaccine. A six-month (July to December, 2012) surveillance, managed by IBD team, collected stool samples and clinical data from under-five children with acute watery diarrhea at an IBD sentinel site. Samples were tested for rotavirus antigen by ELISA and genotyped by PCR at the regional reference laboratory (RRL). Specimens were collected from 79% (n = 297) of eligible cases (n = 375); 100% of which were tested for rotavirus by ELISA and 54% (159/297) of them were positive. At RRL, all the cases were confirmed by PCR and genotyped (99%; 158/159). The typing results revealed the predominance of G12 (40%; 64/159) genotype, followed by G1 (31%; 50/159) and G9 (19%; 31/159). All in all, this exploratory surveillance collected the desired demographic and epidemiological data and achieved almost all the benchmark indicators of WHO, starting from enrollment number to quality assurance through a number of case detection, collection, and testing of specimens and genotyping of strains at RRL. The success of this WHO-IBD site in achieving these benchmark indicators of WHO can be used by WHO as a proof-of-concept for considering integration of rotavirus surveillance with WHO-IBD platforms, specifically in countries with well performing IBD site and no ongoing rotavirus surveillance. 相似文献
92.
The genetics of a spontaneous double mutant Hla, belonging toSaccharomyces carlsbergensis, has been studied. The two mutated loci, controlling the biosyntheses of lysine and uracil are either loosely linked or they are located on separate chromosomes. Spontaneous mutations in the two genes are therefore likely to have followed from two independent mutagenic events. The mating-type locus, the methionine, the lysine and the uracil synthesising loci are not linked. Segregations for mating-type locus are Mendelian where as segregations for lysine, uracil and methionine synthesising loci are both Mendelian and Non-Mendelian. The 4:0 class of Non-Mendelian segregation is not found. The apparently Non-Mendelian segregations for mehtionine synthesis can be explained on the basis of the presence of two complementary methionine synthesising genes in Hla.
Zusammenfassung Die Genetik eines spontanen Doppelmutanten Hla, der zuSaccharomyces carlsbergensis gehört, wurde untersucht. Die zwei Loci, die die Biosynthese von Lysin und Uracil kontrollieren, sind entweder locker gebunden oder sind an verschiedene Chromosomen gebunden. Spontane Mutationen in beiden Genen sind deshalb wahrscheinlich das Ergebnis von zwei unabhängigen mutagenen Faktoren. Der Locus der Geschlechtstype, die Loci der Synthese von Methionine, Lysine und Uracil sind nicht gebunden. Die Absonderung des Locus für die Geschlechtstype ist gemäß Mendel, während die Absonderung für Lysine, Uracil und Methionine teils gemäß, teils nicht gemäß Mendel erfolgt. Die Klasse 4 : 0 der Absonderung nicht gemäß Mendel ist nicht gefunden worden. Die scheinbare Absonderung nicht gemäß Mendel für die Synthese von Methionine kann auf Grund der Gegenwart von zwei komplementären Genen in Hla für die Synthese von Methionine erklärt werden.相似文献
93.
Bovine collagen alpha-1 is a naturally occurring extracellular matrix protein found in tendons and other connective tissues. It plays
a vital role in cell growth, differentiation, attachment, and migration. Recent findings have established that collagen alpha-1 is
involved in osteogenesis imperfecta phenotype in cattle but deep information about other members of this large family is not
available so far. So with a view to finding a new edge and attempt to figure out a correlation among the well attributed Bovine
alpha-1 collagen sequences are executed and analyzed. To do so, comparative analysis among the 28 members of collagen family
has been carried out using Computational tools. Consequently, based on the physico-chemical, secondary structural, functional
and phylogenetic classifications, we have selected collagen 12, 14 and 20 as targets for pathological conditions. These proteins
belong to the FACIT family and significantly showed low glycine and proline content, high instability and aliphatic index.
Moreover, FACIT family collagens contain multiple triple helical domains and being members of the FACIT family, bovine
collagen 12, 14, 20 do not form fibrils by themselves but they are associated to collagen 1 associated fibrils. These collagen
molecules might be crucial candidates to detect and understand the process of matrix remodeling in diseases especially in the arena
of cellular compartments. 相似文献
94.
A. R. Hussain A. S. Khan S. O. Ahmed M. Ahmed L. C. Platanias K. S. Al‐Kuraya S. Uddin 《Cell proliferation》2010,43(2):170-183
Objective: The mechanisms that regulate mitogenic and antiapoptotic signals in primary effusion lymphoma (PEL) are not well known. In efforts to identify novel approaches to block the proliferation of PEL cells, we assessed the effect of apigenin (4′,5,7‐trihydroxyflavone), a flavonoid on a panel of PEL cell lines. Materials and methods: We studied the effect of apigenin on four PEL cell lines. Apoptosis was measured by annexin V/PI dual staining and DNA laddering. Protein expression was measured by immunoblotting. Results: Apigenin induced apoptosis in PEL cell lines in a dose dependent manner. Such effects of apigenin appeared to result from suppression of constitutively active kinase AKT resulting in down‐regulation of SKP2, hypo‐phosphorylation of Rb and accumulation of p27Kip1. Apigenin treatment of PEL cells caused dephosphorylation of p‐Bad protein leading to down regulation of the anti‐apoptotic protein, Bcl‐2 and an increase in Bax/Bcl2 ratio. Apigenin treatment also triggered Bax conformational change and subsequently translocation from cytosole to mitochondria causing loss of mitochondrial membrane potential with subsequent release of cytochrome c. Released cytochrome c onto the cytosole activated caspase‐9 and caspase‐3, followed by polyadenosin‐5′‐diphosphate‐ribose polymerase (PARP) cleavage. Finally, treatment of PEL cells with apigenin down‐regulated the expression of inhibitor of apoptosis protein (IAPs). Conclusions: Altogether, these data suggest a novel function for apigenin, acting as a suppressor of AKT/PKB pathway in PEL cells, and raise the possibility that this agent may have a future therapeutic role in PEL and possibly other malignancies with constitutive activation of the AKT/PKB pathway. 相似文献
95.
Uddin Md. Main Ibrahim Mostafa M. H. Aryal Dinesh Briski Karen P. 《Molecular and cellular biochemistry》2020,473(1-2):39-50
Molecular and Cellular Biochemistry - Hypoglycemia is a detrimental complication of rigorous management of type 1 diabetes mellitus. Moderate hypoglycemia (MH) preconditioning of male rats... 相似文献
96.
Dreier JP Kleeberg J Alam M Major S Kohl-Bareis M Petzold GC Victorov I Dirnagl U Obrenovitch TP Priller J 《Experimental biology and medicine (Maywood, N.J.)》2007,232(2):204-213
Two different theories of migraine aura exist: In the vascular theory of Wolff, intracerebral vasoconstriction causes migraine aura via energy deficiency, whereas in the neuronal theory of Le?o and Morison, spreading depression (SD) initiates the aura. Recently, it has been shown that the cerebrovascular constrictor endothelin-1 (ET-1) elicits SD when applied to the cortical surface, a finding that could provide a bridge between the vascular and the neuronal theories of migraine aura. Several arguments support the notion that ET-1-induced SD results from local vasoconstriction, but definite proof is missing. If ET-1 induces SD via vasoconstriction/ischemia, then neuronal damage is likely to occur, contrasting with the fact that SD in the otherwise normal cortex is not associated with any lesion. To test this hypothesis, we have performed a comprehensive histologic study of the effects of ET-1 when applied topically to the cerebral cortex of halothane-anesthetized rats. Our assessment included histologic stainings and immunohistochemistry for glial fibrillary acidic protein, heat shock protein 70, and transferase dUTP nick-end labeling assay. During ET-1 application, we recorded (i) subarachnoid direct current (DC) electroencephalogram, (ii) local cerebral blood flow by laser-Doppler flowmetry, and (iii) changes of oxyhemoglobin and deoxyhemoglobin by spectroscopy. At an ET-1 concentration of 1 muM, at which only 6 of 12 animals generated SD, a microarea with selective neuronal death was found only in those animals demonstrating SD. In another five selected animals, which had not shown SD in response to ET-1, SD was triggered at a second cranial window by KCl and propagated from there to the window exposed to ET-1. This treatment also resulted in a microarea of neuronal damage. In contrast, SD invading from outside did not induce neuronal damage in the absence of ET-1 (n = 4) or in the presence of ET-1 if ET-1 was coapplied with BQ-123, an ET(A) receptor antagonist (n = 4). In conclusion, SD in presence of ET-1 induced a microarea of selective neuronal necrosis no matter where the SD originated. This effect of ET-1 appears to be mediated by the ET(A) receptor. 相似文献
97.
Two New Species of Zoothamnium (Ciliophora,Peritrichia) from Korea,with New Observations of Z. parahentscheli Sun et al., 2009 下载免费PDF全文
Shahed Uddin Ahmed Shazib Ping Sun Liqiong Li Mann Kyoon Shin 《The Journal of eukaryotic microbiology》2015,62(4):505-518
Three peritrichous ciliates, Zoothamnium arcuatum n. sp., Z. grossi n. sp., and Z. parahentscheli Sun et al., 2009, were collected from an estuary of the Taehwagang River, Korea. All these species were investigated based on live observations and silver staining, and their small subunit (SSU) rRNA gene was also sequenced. Zoothamnium arcuatum can be identified by a goblet‐shaped colony, double‐layered peristomial lip, and abstomally shortened row 3 of infundibular polykinety 3 (P3). Zoothamnium grossi is morphologically characterized by an alternately branched stalk with the lowest secondary stalk diverging from the main part of colony, asymmetrically bell‐shaped zooids, and three short, parallel ciliary rows in P3. Phylogenetic analysis revealed that the three Zoothamnium species described in this paper clustered with other members of the family Zoothamniidae, as expected. 相似文献
98.
Najmul Haider Md. Shafiqur Rahman Salah Uddin Khan Andrea Mikolon Muzaffor G. Osmani Emily S. Gurley Ireen Sultana Shanta Suman Kumer Paul Laura Macfarlane-Berry Ariful Islam Ausraful Islam James Desmond Jonathan H. Epstein Rachael A. Priestley Gilbert J. Kersh Mohammed Ziaur Rahman Peter Daszak Stephen P. Luby Robert F. Massung Nord Zeidner 《EcoHealth》2015,12(2):354-358
99.
100.
Qu YY Zhou JT Wang J Xing LL Jiang N Gou M Salah Uddin M 《Bioresource technology》2009,100(1):244-248
The performances and microbial population changes in laboratory-scale membrane bioreactor (MBR) augmented with Sphingomonas xenophaga QYY were investigated in the present study. It was demonstrated that after 30 days acclimation, the non-augmented MBR system were able to degrade bromoamine acid (BAA) well. However, the efficiency of the system decreased with BAA concentration increasing. While the augmented MBR showed higher capability, in which the color and COD removal were more than 90% and 50%, respectively. By ribosomal intergenic spacer analysis (RISA), it was found that BAA-utilizing populations gradually increased to become the dominant species in the non-augmented MBR. However, the augmented MBR possessed relatively stable treatment abilities, in which the introduced strain QYY could be persistent and co-exist well with the indigenous populations. 相似文献