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71.
Bochenek WJ Peters S Fraga PD Wang W Mack ME Osato MS El-Zimaity HM Davis KD Graham DY;Helicobacter pylori Pantoprazole Eradication 《Helicobacter》2003,8(6):626-642
Aim. To compare the short‐term (7‐day) safety and efficacy of two triple‐therapy regimens using pantoprazole with those of two dual‐therapy regimens (one with pantoprazole and one without), for Helicobacter pylori eradication in patients with peptic ulcer disease. Methods. H. pylori infection was identified by rapid urease (CLOtest), and confirmed by histology and culture. Patients were enrolled into one of two randomized, double‐blind, multicenter, parallel‐group studies. In study A, patients received oral pantoprazole 40 mg, clarithromycin 500 mg, and metronidazole 500 mg (PCM); pantoprazole, clarithromycin and amoxicillin 1000 mg (PCA); or pantoprazole and clarithromycin (PC). In study B, patients received PCM, PCA, PC, or clarithromycin and metronidazole without pantoprazole (CM). Treatments were given twice daily for 7 days. H. pylori status after therapy was assessed by histology and culture at 4 weeks after completing the course of study treatment. Modified intent‐to‐treat (MITT; each study: n = 424, n = 512) and per‐protocol (PP; each study: n = 371, n = 454) populations were analyzed. The MITT population comprised all patients whose positive H. pylori status was confirmed by culture and histology; the PP population comprised patients who also complied with ≥ 85% of study medication doses. Results. A total of 1016 patients were enrolled. Cure rates among patients with clarithromycin‐susceptible H. pylori strains were 82 and 86% for PCM, and 72 and 71% for PCA, in studies A and B, respectively. Cure rates among patients with metronidazole‐susceptible H. pylori strains were 82 and 87% for PCM, and 71 and 69% for PCA, in studies A and B, respectively. The combined eradication rates observed with the PCM regimen were superior to those of all other regimens tested. Side‐effects were infrequent and mild. Conclusions. PCM had the highest overall eradication rate in these two studies examining 7‐day treatment regimens. All regimens were safe and well tolerated. 相似文献
72.
Kaiser P Rothwell L Vasícek D Hala K 《Journal of immunology (Baltimore, Md. : 1950)》2002,168(8):4216-4220
The obese strain (OS) of chickens, which suffers from spontaneous autoimmune thyroiditis, is an excellent animal model for Hashimoto's thyroiditis and provides a unique opportunity to investigate the mechanisms underlying and driving the onset of the disease. Following recent advances in cloning chicken cytokines, we can now begin to investigate the role of cytokines in driving the lymphoid infiltration of the thyroid seen in these birds from day 7 posthatch. Using real-time quantitative RT-PCR, we characterized the expression of IFN-gamma, IL-1beta, IL-2, IL-6, IL-8, IL-15, and IL-18 in thyroids from OS birds and control CB line birds, both in the embryo just before hatch (embryonic day 20) and at 3 and 5 days posthatch. All of these cytokines were up-regulated compared with levels in thyroids from CB birds, at least at some time points, with some evidence for coordination of regulation, e.g., for the proinflammatory cytokines IL-1beta and IL-8. Only IL-15 was up-regulated at all time points. IL-15 was also shown to be up-regulated in spleens of OS birds at embryonic day 20 and 5 days posthatch, suggesting that IL-15 is constitutively up-regulated in this line of birds. This could explain the general immune system hyperreactivity exhibited by OS chickens and may be a factor driving the lymphoid infiltration of the thyroid. 相似文献
73.
Prenylated flavonoids of Erythrina lysistemon grown in Egypt 总被引:1,自引:0,他引:1
Three prenylated flavonoid derivatives; 5,7,4′-trihydroxy-8-(3-methylbut-2-enyl)-6-(2″-hydroxy-3″-methylbut-3″enyl) isoflavone (isoerysenegalensein E), 5,7,2′-trihydroxy-4′-methoxy-5′-(3″-methylbut-2″-enyl) isoflavanone (lysisteisoflavanone), 5, 4′-dihydroxy-6-(3-methylbut-2-enyl)-2″-hydroxyisopropyl dihydrofurano [4″,5″:8,7] isoflavone (isosenegalensin), together with the four known flavonoids abyssinone V-4′-methylether, alpinumisoflavone, wighteone and burttinone were isolated from the stem bark of Erythrina lysistemon Hutch. (Leguminosae). Structures were elucidated by spectroscopic methods. 相似文献
74.
Release of an acid phosphatase activity during lily pollen tube growth involves components of the secretory pathway 总被引:2,自引:0,他引:2
Ibrahim H Pertl H Pittertschatscher K Fadl-Allah E el-Shahed A Bentrup FW Obermeyer G 《Protoplasma》2002,219(3-4):176-183
Summary. An acid phosphatase (acPAse) activity was released during germination and tube growth of pollen of Lilium longiflorum Thunb. By inhibiting components of the secretory pathway, the export of the acPase activity was affected and tube growth
stopped. Brefeldin A (1 μM) and cytochalasin D (1 μM), which block the production and transport of secretory vesicles, respectively,
inhibited the acPase secretion. The Ca2+ channel blocker gadolinium (100 μM Gd3+) also inhibited acPase secretion and tube growth, whereas 3 mM caffeine, another Ca2+ uptake inhibitor, stimulated the acPase release, while tube growth was inhibited. The Yariv reagent (β-D-glucosyl)3 Yariv phenylglycoside stopped tube growth by binding to arabinogalactan proteins of the tube tip cell wall but did not affect
acPase secretion. A strong correlation between tube growth and acPase release was detected. The secreted acPase activity had
a pH optimum at pH 5.5, a K
M of 0.4 mM for p-nitrophenyl phosphate, and was inhibited by zinc, molybdate, phosphate, and fluoride ions, but not by tartrate. In electrophoresis
gels the main acPase activity was detected at 32 kDa. The conspicuous correlation between activity of the secretory pathway
and acPase secretion during tube elongation strongly indicates an important role of the acPase during pollen tube growth and
the secreted acPase activity may serve as a useful marker enzyme assay for secretory activity in pollen tubes
Received July 25, 2001 Accepted January 15, 2002 相似文献
75.
Khaled Gouda Sherihan AbdelHamid Ahmed Mansour Nesreen Omar Hala El-Mesallamy 《Current issues in molecular biology》2021,43(3):1698
Autophagy has been demonstrated to have a beneficial effect on diabetic nephropathy (DN). Rapamycin, an inhibitor of mTOR, was shown to stimulate β-cell autophagy. However, its effects on preventing or ameliorating DN is unclear, and its effects are worth studying. As fasting is now an attractive protective strategy, we aim to compare its effect to rapamycin effects on pancreatic and renal cells. Twenty-eight adult male Wistar Albino rats were randomly divided into four groups, using streptozotocin (STZ) to induce diabetes mellitus (DM). Autophagy was induced by two ways; rapamycin or fasting. The extent of autophagy and apoptosis were investigated by measuring the level of LC3B and p53 proteins, respectively, in pancreatic and kidney tissues using Western blotting (WB) technique and imaging the renal cells under transmission electron microscope. The efflux transporter P-glycoprotein was quantified by WB as well. Rapamycin-induced autophagy occurred concurrently with apoptosis. On the other hand, fasting supported P-glycoprotein recovery and renal cell survival together with disabling β-cells apoptosis. In conclusion, this study provides a potential link between rapamycin or fasting for the cross-regulation of apoptosis and autophagy in the setting of cell stress as DN. Unlike rapamycin, fasting enhanced the active expression of ABCB1 efflux protein, providing insights on the potential ameliorative effects of fasting in DN that require further elucidation. 相似文献
76.
Molecular cloning and expression of a cDNA encoding 1-aminocyclopropane-1-carboxylate (ACC) oxidase from apricot fruit (Prunus armeniaca) 总被引:1,自引:0,他引:1
77.
Hanan Sharaf El-Deen Mohammed Manal Mohamed Kamal Hala Mostafa ElBadre Amal Hosni Azza Abo Elfadl Mohamed Ahmed Mostafa Reham Ibrahim El-Mahdy 《Reports of Biochemistry & Molecular Biology》2022,10(4):537
Background:Oxidized low-density lipoprotein (ox-LDL) has an important role in the genesis of coronary atherosclerosis. Lectin-like ox-LDL receptor 1 (OLR1) contributes to the uptake and internalization of ox-LDL. Genetic polymorphisms have been associated with coronary artery disease (CAD). Here we explore the association of plasma levels of ox-LDL and 3′ UTR OLR1 (rs1050286) SNP with CAD risk and in-hospital adverse outcomes.Methods:A case-control study enrolled 192 patients with ST-segment elevation myocardial infarction (STEMI), 100 patients with unstable angina, and 100 healthy controls. Baseline, clinical characteristics, and risk scores of the patients were determined. Plasma ox-LDL and other biochemical variables were measured. All subjects are genotyped for OLR1 (rs1050286) by RT-PCR with TaqMan SNP genotyping assay.Results:Plasma ox-LDL was higher with enhanced sensitivity and specificity in identifying patients with STEMI and was found as a significant independent risk factor for CAD in those two groups. Levels of ox-LDL were increased with increasing poor prognostic factors in STEMI patients that are associated with an increased incidence of some adverse events and in-hospital mortality. Elevated STEMI risk was associated with T allele of OLR1 (rs1050286) (odds ratio of 4.9, 95% CI: 2.6-9.4, p< 0.001). STEMI patients who have T allele exhibited higher risk scores, coronary multivessel narrowing, and elevated incidence of in-hospital major adverse clinical events.Conclusion:These results suggest that plasma ox-LDL, as well as T allele of ORL-1 (rs1050286), is associated with the increased risk for developing STEMI and the associated adverse clinical outcomes.Key Words: Coronary artery disease, genotyping, OLR1, outcomes, Oxidized low-density lipoprotein 相似文献
78.
Hala B. El-Nassan Bassem H. Naguib Engy A. Beshay 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):58-66
Three series of 2-arylpyridothieno[3,2-d]pyrimidin-4-ones 3a–j, pyridothienotriazolopyrimidines 6–8 and 4-imino-pyridothieno[3,2-d]pyrimidines 9a,b were prepared to improve the pim-1 inhibitory activity of the previously reported 2-arylpyridothieno[3,2-d]pyrimidin-4-ones. All the test compounds showed highly potent pim-1 inhibition with IC50 in the range of 0.06–1.76?µM. No significant difference was detected between the pim-1 inhibitory activity of the 4-pyrimidinone and the 4-imino (=NH) or the cyclised triazolopyrimidine derivatives. The most active compounds were tested for their cytotoxic activity on MCF7 and HCT116 and showed potent activity on both the cell lines. 相似文献
79.
Ryanodine receptor regulation by intramolecular interaction between cytoplasmic and transmembrane domains
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George CH Jundi H Thomas NL Scoote M Walters N Williams AJ Lai FA 《Molecular biology of the cell》2004,15(6):2627-2638
Ryanodine receptors (RyR) function as Ca(2+) channels that regulate Ca(2+) release from intracellular stores to control a diverse array of cellular processes. The massive cytoplasmic domain of RyR is believed to be responsible for regulating channel function. We investigated interaction between the transmembrane Ca(2+)-releasing pore and a panel of cytoplasmic domains of the human cardiac RyR in living cells. Expression of eGFP-tagged RyR constructs encoding distinct transmembrane topological models profoundly altered intracellular Ca(2+) handling and was refractory to modulation by ryanodine, FKBP12.6 and caffeine. The impact of coexpressing dsRed-tagged cytoplasmic domains of RyR2 on intracellular Ca(2+) phenotype was assessed using confocal microscopy coupled with parallel determination of in situ protein: protein interaction using fluorescence resonance energy transfer (FRET). Dynamic interactions between RyR cytoplasmic and transmembrane domains were mediated by amino acids 3722-4610 (Interacting or "I"-domain) which critically modulated intracellular Ca(2+) handling and restored RyR sensitivity to caffeine activation. These results provide compelling evidence that specific interaction between cytoplasmic and transmembrane domains is an important mechanism in the intrinsic modulation of RyR Ca(2+) release channels. 相似文献
80.
The purpose of this work is to design a rheological analogue to periprosthetic fluid, for potential use in wear testing of orthopaedic implants. Polymer solutions of sodium carboxymethyl cellulose (CMC), xanthan and mixtures thereof were prepared, and the experimentally determined viscosity-shear rate dependence was analyzed using the three-parameter modified Cross model. A mixture containing 0.185 wt% CMC and 0.075 wt% xanthan was identified as being the closest rheological match for periprosthetic fluid in both steady shear and oscillatory modes of deformation. 相似文献