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61.
Zinc and copper status in acute pancreatitis: an experimental study   总被引:2,自引:0,他引:2  
Metal ions are required as active components of several proteins, including pancreatic enzymes, and they can play important roles in the etiopathogenesis of acute pancreatitis. In the present study, we measured the concentrations of zinc (Zn) and copper (Cu) in both serum and pancreatic tissue, as markers of trace element status in an experimental acute pancreatitis model. Twenty-four male Wistar rats were divided into two groups: the experimental group (N=24) and the control group (N=10). Acute pancreatitis was induced by injection of 48% ethyl alcohol into the common biliary duct. The animals were sacrificed 24 h later to detect the concentrations of Zn and Cu. There was no significant difference in tissue Zn and Cu concentrations between control and experimental groups (p<0.05). However, in the acute pancreatitis group, serum Zn and Culevels were very significantly lower (p<0.001 and p<0.0001, respectively). In conclusuion, these findings suggested that altered mineral metabolism in serum and pancreatic tissue may have contributed to the pathophysiology of acute pancreatitis.  相似文献   
62.
Phlomis linearis Boiss. & Bal. of the Lamiaceae family growing in central, east and southeast Anatolia is an endemic species for Turkey. The essential oil obtained from the aerial parts by hydro distillation was subsequently analyzed by GC/MS. The main components of the oil were found as beta-caryophyllene (24.2%), germacrene D (22.3%) and caryophyllene oxide (9.2%), among 49 identified compounds, representing 94.5% of the total essential oil. The overall biological activity of the essential oil (100 microg/pellet) was tested on the chorioallantoic membrane (CAM) of the fertilized hen's egg in order to examine the anti-angiogenic and anti-inflammatory activity. None of the tests showed pronounced activity, toxicity or irritation at the tested concentration.  相似文献   
63.
Activation and robust expansion of naive T cells often require T cell costimulatory signals and T cell growth factors. However, the precise growth and costimulation requirements for activation and expansion of CD4(+) and CD8(+) T cells in vivo in allograft response are still not clearly defined. In the present study, we critically examined the role of CD28/CD40 ligand (CD40L) costimulation and the common gamma-chain (gamma(c)) signals, a shared signaling component by receptors for all known T cell growth factors (i.e., IL-2, IL-4, IL-7, IL-9, IL-15, IL-21), in activation and expansion of CD4(+) and CD8(+) T cells in the allogeneic hosts. We found that CD28/CD40L costimulation and the gamma(c) signals are differentially involved in proliferation and clonal expansion of CD4(+) and CD8(+) T cells in response to alloantigen stimulation. CD8(+) T cells are highly dependent on the gamma(c) signals for survival, expansion, and functional maturation, whereas in vivo expansion of alloreactive CD4(+) T cells is largely gamma(c) independent. T cell costimulation via CD28 and CD40L, however, is necessary and sufficient for activation and expansion of CD4(+) T cells in vivo. In a skin transplant model, blocking both CD28/CD40L and the gamma(c) pathways induced prolonged skin allograft survival. Our study provides critical insights that the CD4 and CD8 compartments are most likely governed by distinct mechanisms in vivo, and targeting both costimulatory and gamma(c) signals may be highly effective in certain cytopathic conditions involving activation of both CD4(+) and CD8(+) T cells.  相似文献   
64.
The effects of various fungicides on mycelial growth and spore germination of Ascochyta rabiei were determined by incorporating them into potato dextrose agar and measuring colony diameter and observing colony growth and spore germination at 20 ± 2°C. Eight fungicides prevented spore germination of the pathogen at concentrations of 0.125–2 μg/ml, three hindered mycelial growth at 2–4 μg/ml and seven failed to inhibit mycelial growth even at 128 μg/ml. The reference fungicide for the pathogen, chlorothalonil, stopped conidial germination at low rates but did not prevent mycelial growth at 128 μg/ml. Thirteen fungicides were tested against seed infections of the pathogen, and benomyl + thiram, carbendazim and carbendazim + chlorothalonil seed treatments gave more than 85% inhibition on both vacuum‐infiltrated and naturally infected seeds. Coating the seeds with polymers did not increase the effectiveness of fungicides. Three fungicides; (azoxystrobin, chlorothalonil and mancozeb), gave the highest protection in the field but protection decreased with increased inoculum pressure. Addition of humic acid to fungicide suspensions did not affect their performance.  相似文献   
65.
Lactoperoxidase enzyme (LPO) is secreted from salivary, mammary, and other mucosal glands including the bronchi, lungs, and nose, which had functions as a natural and the first line of defense towards viruses and bacteria. In this study, methyl benzoates were examined in LPO enzyme activity. Methyl benzoates are used as precursors in the synthesis of aminobenzohydrazides used as LPO inhibitors. For this purpose, LPO was purified in a single step using sepharose-4B-l-tyrosine-sulfanilamide affinity gel chromatography with a yield of 9.91 % from cow milk. Also, some inhibition parameters including the half maximal inhibitory concentration (IC50) value and an inhibition constant (Ki) values of methyl benzoates were determined. These compounds inhibited LPO with Ki values ranging from 0.033±0.004 to 1540.011±460.020 μM. Compound 1 a (methyl 2-amino-3-bromobenzoate) showed the best inhibition (Ki=0.033±0.004 μM). The most potent inhibitor ( 1 a ) showed with a docking score of −3.36 kcal/mol and an MM-GBSA value of −25.05 kcal/mol, of these methyl benzoate derivatives ( 1 a – 16 a ) series are established H-bond within the binding cavity with residues Asp108 (distance of 1.79 Å), Ala114 (distance of 2.64 Å), and His351 (distance of 2.12 Å).  相似文献   
66.
The cyclic monoterpene ketone (-)-carvone was metabolized by the plant pathogenic fungus Absidia glauca. After 4 days of incubation, the diol 10-hydroxy-(+)-neodihydrocarveol was formed. The absolute configuration and structure of the crystalline substance was identified by means of X-ray diffraction and by spectroscopic techniques (MS, IR and NMR). The antimicrobial activity of the substrate and metabolite was assayed with human pathogenic microorganisms.  相似文献   
67.
Between April 2001 and April 2002 were studied 106 women with a clinical diagnosis of vaginal candidiasis seen at the Gynecology and Obstetrics Ambulatory of the Hospital das Clínicas da Universidade Federal de Goiás. The patients were assessed on two occasions, before starting treatment with itraconazole or fluconazole (initial visit) and 14 days after treatment (return). At two visits the signs and symptoms were recorded and vaginal secretion was collected. According to the clinical evaluation, itraconazole was effective in 64.3%, while fluconazole was effective in 71.0% of the patients. The mycological cure rates (negative culture) in the return were 64.3% for the patients treated with itraconazole and 78.9% for the patients treated with fluconazole. The MICs of itraconazole and fluconazole for 80 Candida isolates were determined by Etest method. We investigated the correlation between in vitro susceptibility (Susceptible, Susceptibility Depending Dose and Resistant) to itraconazole and fluconazole with clinical outcome of the patients. The success rates were 63.9% for itraconazole and 90.6% for fluconazole in the susceptible category, 100.0% for both drugs in the susceptible dose dependent category, and 0.0% for both drugs in the resistant category. Our results showed there were a positive correlation between in vitro susceptibility test results with clinical outcome in vaginal Candida infections and that both drugs might be one choice in the treatment of vaginal candidiasis.  相似文献   
68.
Critical role of OX40 in CD28 and CD154-independent rejection   总被引:20,自引:0,他引:20  
Blocking both CD28 and CD154 costimulatory pathways can induce transplant tolerance in some, but not all, transplant models. Under stringent conditions, however, this protocol often completely fails to block allograft rejection. The precise nature of such CD28/CD154 blockade-resistant rejection is largely unknown. In the present study we developed a new model in which both CD28 and CD154, two conventional T cell costimulatory molecules, are genetically knocked out (i.e., CD28/CD154 double-knockout (DKO) mice) and used this model to examine the role of novel costimulatory molecule-inducible costimulator (ICOS), OX40, 4-1BB, and CD27 in mediating CD28/CD154-independent rejection. We found that CD28/CD154 DKO mice vigorously rejected fully MHC-mismatched DBA/2 skin allografts (mean survival time, 12 days; n = 6) compared with the wild-type controls (mean survival time, 8 days; n = 7). OX40 costimulation is critically important in skin allograft rejection in this model, as blocking the OX40/OX40 ligand pathway, but not the ICOS/ICOS ligand, 4-1BB/4-1BBL, or CD27/CD70 pathway, markedly prolonged skin allograft survival in CD28/CD154 DKO mice. The critical role of OX40 costimulation in CD28/CD154-independent rejection is further confirmed in wild-type C57BL/6 mice, as blocking the OX40/OX40 ligand pathway in combination with CD28/CD154 blockade induced long term skin allograft survival (>100 days; n = 5). Our study revealed a key cellular mechanism of rejection and identified OX40 as a critical alternative costimulatory molecule in CD28/CD154-independent rejection.  相似文献   
69.
Detoxification of an antifungal monoterpene terpinolene (1) by the plant pathogenic fungus Botrytis cinerea afforded hydroxlyated metabolites 2,3-dihydro-3beta,6beta-dihydroxy-terpinolene (2) (39%) and 2,3-dihydro-1alpha,3alpha-dihydroxy-terpinolene (3) (20%), respectively. Terpinolene showed good levels of antifungal activity while both the metabolites were inactive against another plant pathogenic fungus Cladosporium herbarun.  相似文献   
70.
In the course of our continuing work on transformation of monoterpenes by microorganisms, the biotransformation of (+)- and (-)-carvone was carried out. The metabolites formed during microbial transformations were screened using a simple, rapid and efficient technique: Headspace-solid phase microextraction (SPME)/GC-MS. The results as well as the application of this technique are described.  相似文献   
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