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101.
Background:  Eradication rates of Helicobacter pylori have declined to unacceptable levels in recent years. New and effective treatment options are warranted both as a first and second line treatment.
Aim:  To test an effectiveness of modified sequential therapy with levofloxacin for H. pylori eradication in Turkey.
Material and Methods:  Helicobacter pylori infected dyspeptic patients were included to the study. Subjects were treated with modified sequential therapy consisting of rabeprazole 20 mg b.i.d. and amoxicillin 1 g b.i.d., for 7 days followed by rabeprazole 20 mg b.i.d, levofloxacin 500 mg q.d. and metronidazole 500 mg b.i.d for the remaining 7 days.
Results:  Sixty-three treatment naive patients and 37 previous treatment failures were enrolled to the study (59 F, 41 M, age: 21–80 years). There was five drop out. Helicobacter pylori eradication was achieved in 80 patients, intention-to-treat (ITT): 80% (95% CI: 71–87%) and per-protocol (PP): 84.2% (95% CI: 75–91%), totally. In treatment naive patients ITT and PP eradication rates were 82.5% (95% CI: 71–91%), and 86.7% (95% CI: 75–94%), respectively. As a second line treatment eradication was successful in ITT 75.7%.(95% CI: 59–88%), and PP 80% (95% CI: 63–92%).Mild side effects were reported by 8 patients (8.4%).
Conclusions:  Sequential therapy using "rabeprazole and amoxicillin 7 days followed by rabeprazole, metronidazole and levofloxacin for 7 days" is a new regimen with acceptable eradication rates in naïve patients in Turkey. Further modifications in the dose or duration of this new sequential therapy might increase its effectiveness as both first and second line treatment.  相似文献   
102.
Species composition and distribution of large intestinal ciliates was investigated in the feces from 13 Cypriot wild donkeys, free-living in the Karpaz national park, Northern Cyprus. We identified 16 ciliate genera and 22 species. This is the first report on intestinal ciliates in Cypriot wild donkeys, and no endemic species were observed. The genus Cycloposthium occurred in all animals. The mean number of ciliates was 3.0±2.5×104 cells ml?1 of feces and the mean number of ciliate species per host was 6.5±4.8. Characteristics of the wild donkey ciliates was almost identical to those reported in other equids from various regions around the world. We thus conclude that there is no pronounced geographic variation in the intestinal ciliate fauna of equids.  相似文献   
103.
Alkaptonuria (ochronosis) is a rare autosomal recessive disorder featuring a genetic error in the amino acid metabolism. A defect in the tyrosine metabolism results in the accumulation and deposition of homogentisic acid in connective tissue, causing a blue-black discolouration. Degenerative arthropathy of the spine, knee, and hip are common signs of ochronosis in older age. An association between ochronosis and depression has not previously been discussed in the literature. This case report describes a 69 year-old woman with diabetes mellitus, ochronosis, depression and chronic pain.  相似文献   
104.
There are strong indications, but as yet no proof, that extended  48-bp Flp recombinase targets (FRTs) represent unique targets in all eukaryotic genomes investigated, and that recombinase-mediated cassette exchange is not hampered by the occurrence of genomic pseudo sites. This encouraged the present study in which we explore the feasibility of exchanging, in a given cell, two distinct genomically anchored cassettes, each flanked by a unique set of two heterospecific FRT sites. Mutant FRTs have to meet two major prerequisites for successful recombinase-mediated cassette exchange: (i) a self-recognition capacity comparable to a pair of FRT wild-type sites (FRT × FRT  ), and (ii) a negligible cross-interaction if part of a set of heterospecific sites (F′ × F). We apply a two-step strategy to explore various newly created FRT spacer mutants for these properties. As a result of our screening steps, we identify combinations of sites that are successfully applied to parallel Flp-mediated genomic targeting (“multiplexing”) reactions (i.e., the simultaneous exchange of two separate target cassettes in a given cell).  相似文献   
105.
Background: The mouse double minute 2 (MDM2) gene represents one of the central nodes in the p53 pathway. A naturally occurring T/G single nucleotide polymorphism (SNP) in the intronic promoter of MDM2, SNP309 (rs2279744), was shown to influence MDM2 expression and p53 activity. SNP in the promoter region of MDM2 gene has recently been shown to be associated with accelerated tumor formation in both hereditary and sporadic cancers in humans. In this study, we aim to evaluate the association of SNP309 with the risk of hepatocellular carcinoma (HCC) development among Turkish population. Methods: MDM2 SNP309 polymorphism was investigated in 110 confirmed subjects with HCC and 110 cancer-free control subjects matched on age, gender, smoking and alcohol consumption by using a polymerase chain reaction-restriction fragment length polymorphism assay. Results: The allele frequencies of case subjects (T, 0.48; G, 0.52) were significantly different from those of control subjects (T, 0.65; G, 0.35) (p = 0.003). The proportion of GG genotype of the SNP309 in patients with HCC (26%) was significantly higher than that in patients without HCC (14%). We observed that compared with the TT genotype, the genotypes containing G allele [TG (OR, 2.19; 95% CI, 1.18–4.07; p = 0.013) or GG (OR, 3.63; 95% CI, 1.65–8.00; p = 0.001)] were associated with significant increased susceptibility to HCC. Conclusion: Our findings suggest that the MDM2 promoter SNP309 G allele is associated with presence of HCC in Turkish population.  相似文献   
106.
Polyphenol oxidase (PPO) of Thymbra (Thymbra spicata L. var. spicata) was isolated by (NH4)2SO4 precipitation and dialysis. A diphenolase from Thymbra plant, active against 4-methylcatechol, catechol and pyrogallol was characterized in detail in terms of pH and temperature optima, stability, kinetic parameters and inhibition behaviour towards some general PPO inhibitors. 4-Methylcatechol was the most suitable substrate, due to the lowest Km and the biggest Vmax/Km values, followed by catechol and pyrogallol. The Thymbra PPO had maximum activity at pH 5.0, 7.0 and 8.0 with 4-methylcatechol, catechol and pyrogallol substrates, respectively. The optimum temperature of activity for Thymbra PPO was 30, 40 and 50 °C for 4-methylcatechol, catechol and pyrogallol substrates, respectively. It was found that optimum temperature and pH were substrate-dependent studied. The enzyme activity decreased due to heat denaturation of the enzyme with increasing temperature and inactivation time. Inhibition of Thymbra PPO was investigated with inhibitors such as l-cysteine and glutathione using 4-methylcatechol, catechol and pyrogallol as substrates. It was found that l-cysteine was a more effective inhibitor than glutathione owing to lower Ki. The type of inhibition depended on the origin of the PPO studied and also on the substrate used. Furthermore, the IC50 values of inhibitors sudied on PPO were determined by means of activity percentage (I) diagrams.  相似文献   
107.
In this study, we investigated the effects of erythropoietin (Epo), and pentoxifylline (Ptx) on the oxidant and antioxidant systems in the experimental short bowel syndrome. Spraque-Dawley rats were divided into four groups and all animals underwent 75% small bowel resection. Group E was treated with 500 IU kg(- 1) Epo subcutaneously (s.c.), group P with 50 mg kg(- 1) day(- 1) s.c. Ptx and group E+P with 500 IU kg(- 1) s.c. Epo plus 50 mg kg(- 1) day(- 1) s.c. Ptx for a period of 28 days. In group C, which is the control group, no drug treatment was given. At the end of 28 days the experimented rats were killed and ileum samples excised for biochemical and histopathological testing. Malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels were determined in ileum homogenates. When compared to group C, the MDA and GSH-Px levels were significantly decreased (p < 0.05), but SOD activity was not changed (p > 0.05) in groups P and E+P, whereas both MDA and SOD and also GSH-Px activities were not changed significantly in group E (p > 0.05). The average villous length, crypt depth, muscular thickness and mucosal length were measured in all groups. The average crypt depth and mucosal length were statistically higher in the group P than group C (p < 0.001, p < 0.01, respectively). In addition, the crypt depth was statistically higher in both E and E+P groups as compared to group C (p < 0.001, p < 0.01, respectively). Therefore, our study indicates that Ptx may be more effective than Epo in reducing lipid peroxidation. Moreover, we considered that Ptx may give this protective effect by inhibiting the free oxygen radicals to a greater extent than developing the antioxidant capacity.  相似文献   
108.
One of the main causes leading to mortality in diabetes is myocardial disease. Using streptozotocin (STZ)-induced diabetic animals, it has been possible to characterize diabetes-induced myocardial abnormalities. Interstitial and microvascular disorders are known to be a characteristic part of the diabetic cardiomyopathy and partly resist insulin therapy. Because diabetic damage is partly attributed to oxidative stress, antioxidant treatment may be able to reduce this damage. The aim of this study was to investigate the cardioprotective effect of sodium selenite, known as an antioxidant agent. The diabetes was induced by ip injection of 50 mg/kg body wt STZ. The duration of diabetes was 5 wk. The protected group received (ip) 5 μmol/kg body wt/d sodium selenite (Na2SeO3) over 4 wk following diabetes induction. Electron and light microscopic morphometry of heart samples revealed typical diabetic alterations consisting in an increase in collagen content, vacuolation, diminishing of the cardiomyocyte diameter, alteration in myofilaments and Z-lines of myofibers, and myofibrillary degeneration. Sodium selenite treatment could prevent the loss of myofibrills and reduction of myocyte diameter. In the sodium-selenite-treated diabetic rat heart, alterations of the discus intercalaris and nucleus were corrected, and degenerations seen in myofilaments and Z-lines were reversed by this treatment. Under these findings, one can suggest that sodium selenite treatment may alleviate late diabetic complications when it is used under control conditions.  相似文献   
109.
Selenium (Se) has long been recognized as both an essential mammalian nutrient and a hazardous element. Sodium selenite is commonly used as a dietary supplement for the treatment of Se deficiency. On the other hand, chronic Se toxicity has been demonstrated to affect the major organs, including the heart, in experimental animals. This study examines the effects of high concentrations of extracellular selenite (in the range of 0.001–1 mM) application into the recording bath on the electrical properties of rat papillary muscles. Conventional glass semifloating microelectrodes were used to record intracellular action potentials (APs) in isolated rat papillary muscles. The amplitude of APs and the resting membrane potential of papillary muscles were not changed following a 20-min selenite (1 mM) application compared to the first minute of its application. Freshly isolated ventricular myocytes by an enzymatic method were used to determine the selenite-induced alterations in Na+ currents. Na+ currents, measured at 22°C, by the whole-cell patch-clamp technique, decreased by 38±8% in the presence of 1 mM selenite for 5 min. These selenite-induced effects were not reversed, but are restored by dithiothreitol (1 mM). These results demonstrated that toxic concentrations of selenite induced a significant shortening in AP duration as a result of an increase in the rate of repolarization. Our findings also suggest that a decrease in Na+ currents, in addition to Ca2+ currents, may play a role in the shortening of AP duration in rat papillary muscles.  相似文献   
110.
The present study was conducted to assess the epidemiological relation of Staphylococcus aureus isolates from nasal carriers of hospital staff. Nasal swabs were taken from each of 327 personnel. After culturing on blood agar for overnight, probable staphylococcal isolates were identified and subjected to tube coagulase test. After a two-week interval, second nasal swabs were taken from the subjects whose first cultures were positive for S. aureus. Nasal carriage was defined in 58 (17.7%) personnel with positive culture for both sampling time. Antibiogram typing and arbitrarily-primed polymerase chain reaction (AP-PCR) with M13 primer were used for typing of the strains. Antibiotyping distinguished seven types and three subtypes, and 85% of the isolates were clustered in one group. AP-PCR, in contrast, identified 12 distinct patterns with 13 variants. A specific profile was not found among the isolates obtained from the personnel in a particular clinic. These results indicate that antibiotyping has poor discrimination power and heterogeneity among the nasal S. aureus strains in the hospital personnel screened is high.  相似文献   
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