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1.
B J Stoll R I Glass H Banu M I Huq M U Khan M Ahmed 《BMJ (Clinical research ed.)》1983,286(6383):2037-2040
Findings of stool examinations in 1593 patients with diarrhoea due to a single enteric pathogen--enterotoxigenic Escherichia coli rotavirus, Shigella, Campylobacter jejuni, Vibrio cholerae 0:1, Entamoeba histolytica, or Giardia lamblia--were reviewed to determine how well they predicted the agent associated with the diarrhoea. Specimens were examined visually for blood and mucus, tested for pH, and examined under a microscope for the presence of red and white blood cells, parasites, and stool fat. Although visible blood was more common in specimens from patients infected with Shigella (51%) and Ent histolytica (39%) than in those from patients infected with other agents (6%; p less than 0.01), patients infected with Shigella were most likely to have numerous faecal leucocytes (greater than 50/high power field: 39% v 8% of all patients and 7% of patients infected with Ent histolytica, p less than 0.01 in both cases). Patients infected with enterotoxigenic E coli, rotavirus, V cholerae 0:1, or C jejuni had loose stools with fewer red or white cells. Patients infected with rotavirus and C jejuni were more likely to have acid stools with 3 to 4+ fat, but these findings were related to young age and breast feeding. Stool examination is most useful in establishing a diagnosis of dysentery and in helping to distinguish between patients infected with Shigella and Ent histolytica; it is of limited usefulness in discriminating between pathogens causing watery diarrhoea. 相似文献
2.
M J Banu K Nellaiappan S Dhandayuthapani 《Japanese journal of medical science & biology》1992,45(3):137-150
Mitochondrial malate dehydrogenase (mMDH) and malic enzyme (mME) of a filarial worm Setaria digitata were studied. mMDH exhibited the highest activities in the oxidation and reduction reactions at pH 9.5 and pH 6.2, respectively, while mME did so in the malate decarboxylation reaction at pH 6.8. mME showed no detectable activity on the pyruvate carboxylation direction. The Km values for malate (1.7 mM) and oxaloacetate (0.17 mM) and the ratio of Vmax oxidation: Vmax reduction (2.73) tend to favor the oxaloacetate reduction by mMDH. mME showed a relatively high Km value of 8.3 mM, for malate decarboxylation. A drug, diethylcarbamazine citrate (DEC-C), did not change appreciably the activity of either mMDH or mME, while filarin (a drug of herbal origin) effectively inhibited mMDH. The leaf extracts of Ocimum sanctum, Lawsonia inermis and Calotropis gigantea and leaf and flower extracts of Azadirachta indica were, however, found to inhibit both mMDH and mME. 相似文献
3.
Anlar B Gunel-Ozcan A 《The international journal of biochemistry & cell biology》2012,44(9):1385-1389
Tenascin-R (TN-R), a member of the tenascin family of extracellular matrix glycoproteins, is exclusive to the nervous system. It affects cell migration, adhesion and differentiation, although no remarkable clinical consequences have been shown in knock-out animal models. TN-R's expression pattern suggests a possible primary or secondary role in certain neurological problems including malformations, tumors and neurodegenerative disorders. This review summarizes the structure and molecular interactions of this molecule and discusses its function and possible roles in the central nervous system. 相似文献
4.
Kawther Aabed Nadine Moubayed Saleha Alzahrani 《Saudi Journal of Biological Sciences》2021,28(7):3776-3782
Antimicrobial resistance patterns among different Escherichia coli isolates in the Kingdom of Saudi Arabia. This study aimed to investigate the patterns of antimicrobial resistance in E. coli isolated from different samples, and to identify potential pathogenic isolates in Riyadh, Kingdom of Saudi Arabia (KSA). In total, 51 bacterial isolates were recovered from 113 samples of human urine, food (raw meat, raw chicken, raw egg surface, and fresh vegetables), water, and air. Twenty-four E. coli isolates were tested for susceptibility to 26 antibiotics. The air sample isolates were most resistant to amoxicillin, ampicillin, amoxicillin/clavulanic acid, amoxicillin/sulbactam, piperacillin/tazobactam, cefalotin, cefuroxime, cefoxitin, cefixime, nitrofurantoin, and trimethoprim/sulfamethoxazol. The isolates from vegetable samples were resistant to amoxicillin, ampicillin, amoxicillin/clavulanic acid, amoxicillin/sulbactam, cefalotin, cefuroxime, cefoxitin, and cefixime. By contrast, the isolates from the water samples were resistant only to amoxicillin and ampicillin. The isolates from the human urine samples were most frequently resistant to norfloxacin (80%) followed by amoxicillin and ampicillin (70%), trimethoprim/sulfamethoxazole (55%), ciprofloxacin and ofloxacin (50%), cefalotin (30%), cefuroxime, cefixime and cefotaxime (25%), ceftazidime, ceftriaxone, cefepime and aztreonam (20%), amoxicillin/clavulanic acid, piperacillin/tazobactam and gentamicin (10%), and amoxicillin/sulbactam and cefoxitin (5%). Almost all (23/25, 95.8%) (n = 23) of the isolates were multi-drug resistant (MDR) (i.e., resistant to 3 or more classes of antibiotics), and 16.7% (n = 4) of those were positive for extended spectrum β-lactamase (ESBL). Of the 4 ESBL-producers, 3 were positive for blaCTX-M-15 and blaCTX-M1group, 2 were positive for blaCMY-2, and 1 each was positive for blaCTX-M-2 group, blaSHV, and blaOXA-47. The quinolone resistance gene qnrS was detected in 25% (n = 6) of the E. coli strains isolated from urine (N = 5) and air (N = 1) samples. The considerable number of antimicrobial resistance genes detected among E. coli isolates tested here is alarming and should raise public health concern. 相似文献
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Saleha B. Vuyyuri Jacob Rinkinen Erin Worden Hyekyung Shim Sukchan Lee Keith R. Davis 《PloS one》2013,8(6)
Ascorbic acid (AA) exhibits significant anticancer activity at pharmacologic doses achievable by parenteral administration that have minimal effects on normal cells. Thus, AA has potential uses as a chemotherapeutic agent alone or in combination with other therapeutics that specifically target cancer-cell metabolism. We compared the effects of AA and combinations of AA with the glycolysis inhibitor 3-(3-pyridinyl)-1-(4-pyridinyl)-2-propen-1-one (3-PO) on the viability of three non-small cell lung cancer (NSCLC) cell lines to the effects on an immortalized lung epithelial cell line. AA concentrations of 0.5 to 5 mM caused a complete loss of viability in all NSCLC lines compared to a <10% loss of viability in the lung epithelial cell line. Combinations of AA and 3-PO synergistically enhanced cell death in all NSCLC cell lines at concentrations well below the IC50 concentrations for each compound alone. A synergistic interaction was not observed in combination treatments of lung epithelial cells and combination treatments that caused a complete loss of viability in NSCLC cells had modest effects on normal lung cell viability and reactive oxygen species (ROS) levels. Combination treatments induced dramatically higher ROS levels compared to treatment with AA and 3-PO alone in NSCLC cells and combination-induced cell death was inhibited by addition of catalase to the medium. Analyses of DNA fragmentation, poly (ADP-ribose) polymerase cleavage, annexin V-binding, and caspase activity demonstrated that AA-induced cell death is caused via the activation of apoptosis and that the combination treatments caused a synergistic induction of apoptosis. These results demonstrate the effectiveness of AA against NSCLC cells and that combinations of AA with 3-PO synergistically induce apoptosis via a ROS-dependent mechanism. These results support further evaluation of pharmacologic concentrations of AA as an adjuvant treatment for NSCLC and that combination of AA with glycolysis inhibitors may be a promising therapy for the treatment of NSCLC. 相似文献
7.
Mycopathologia - Dermatophytes are ascomycetous fungi whose sexuality is greatly influenced by their ecology. Sexual reproduction is ubiquitous among soil-related geophiles and some... 相似文献
8.
Hyun Seok Kim Saurabh Mendiratta Jiyeon Kim Chad Victor Pecot Jill E. Larsen Iryna Zubovych Bo Yeun Seo Jimi Kim Banu Eskiocak Hannah Chung Elizabeth McMillan Sherry Wu Jef De Brabander Kakajan Komurov Jason E. Toombs Shuguang Wei Michael Peyton Noelle Williams Adi F. Gazdar Bruce A. Posner Rolf A. Brekken Anil K. Sood Ralph J. Deberardinis Michael G. Roth John D. Minna Michael A. White 《Cell》2013
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Plants have evolved complex signaling pathways to coordinate responses to developmental and environmental Information. The oxylipin pathway Is one pivotal lipid-based signaling network, composed of several competing branch pathways, that determines the plant's ability to adapt to various stimuli. Activation of the oxyllpln pathway Induces the de novo synthesis of biologically active metabolltes called "oxyllplns". The relative levels of these metabolltes are a distinct indicator of each plant species and determine the ability of plants to adapt to different stimuli. The two major branches of the oxyllpln pathway, allene oxide synthase (AOS) and hydroperoxlde lyase (HPL) are responsible for production of the signaling compounds, jasmonates and aldehydes respectively. Here, we compare and contrast the regulation of AOS and HPL branch pathways In rice and Arabidopsis as model monocotyledonous and dicotyledonous systems. These analyses provide new Insights Into the evolution of JAs and aldehydes signaling pathways, and the complex network of processes responsible for stress adaptations In monocots and dicots. 相似文献