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21.
AIM: The protective effect of L-carnitine on stress-induced gastric mucosal injury was investigated in rats exposed to cold-restraint stress (CRS). METHODS: The animals were divided into four groups. Groups 1 and 3 received saline by intragastric gavage for 10 days. Groups 2 and 4 received L-carnitine (50 mg/Kg/day) in the same manner. Groups 3 and 4 were exposed to CRS in the form of immobilization at 4 degrees C for 4 h on day 10. Ulcer index, gastric acid secretion and hemoglobin leakage, and gastric mucosal mucin and PGE2 content were measured. RESULTS: In rats exposed to CRS, as compared to control rats (group 1), ulcer index was higher, gastric acid production was lower, hemoglobin leakage into the gastric lumen was increased, and gastric mucosal mucin and PGE content were reduced. L-carnitine treatment prior to CRS led to attenuation of changes in ulcer index, gastric acid secretion, amount of hemoglobin leakage into the gastric lumen and gastric PGE2 content. In rats receiving L-carnitine but not exposed to CRS, gastric acid secretion, mucin and PGE2 content of gastric mucosa were similar to those in control rats. CONCLUSION: L-carnitine decreases CRS-induced gastric mucosal injury.  相似文献   
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Copolymer 1 [Cop1, glatiramer acetate, Copaxone, poly(Y,E,A,K)n] is widely used in the treatment of relapsing/remitting multiple sclerosis in which it reduces the frequency of relapses by approximately 30%. In the present study, copolymers with modified amino acid compositions (based on the binding motif of myelin basic protein 85-99 to HLA-DR2) have been developed with the aim of suppressing multiple sclerosis more effectively. The enhanced efficacy of these copolymers in experimental autoimmune encephalomyelitis (EAE) induced in SJL/J mice with proteolipid protein 139-151 was demonstrated by using three protocols: (i) simultaneous administration of autoantigen and copolymer (termed prevention), (ii) pretreatment with copolymers (vaccination), or (iii) administration of copolymers after disease onset (treatment). Strikingly, in the treatment protocol administration of soluble VWAK and FYAK after onset of disease led to stasis of its progression and suppression of histopathological evidence of EAE. The mechanisms by which these effects are achieved have been examined in several types of assays: binding of copolymers to I-A(s) in competition with proteolipid protein 139-151 (blocking), cytokine production by T cells (T helper 2 polarization), and transfer of protection by CD3(+) splenocytes or, notably, by copolymer-specific T cell lines (induction of regulatory T cells). The generation of these copolymer-specific regulatory T cells that secrete IL-4 and IL-10 and are independent of the immunizing autoantigen is very prominent among the multiple mechanisms that account for the observed suppressive effect of copolymers in EAE.  相似文献   
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Gemcitabine and cisplatin are the active agents in metastatic breast cancer pretreated with anthracycline and/or taxane as a second line treatment. The present study was designed to assess the efficacy and safety of this regimen given biweekly schedule in these patients. Twenty-seven women, median age 57, with metastatic breast cancer previously treated with anthracycline and taxane were eligible for enrollment. Gemcitabine was administered intravenously on days 1 and 15 at a dose of 2,000 mg/m(2) and Cisplatin was given intravenously on day 1 and 15 at a dose of 50 mg/m(2). Treatment cycles were repeated on an outpatient basis every 28 days. Of all 27 evaluable patients, the overall response rate was 26% (7 of 27; 95% CI: 11-46%) with seven all partial responses. The stable diseases were found in 9 (33%) patients. At the time of last follow-up, 11 (41%) of the patients died of their disease progression. The median overall survival duration was 7.4 +/- 2.8 months. The 1-year overall survival rate was 46.9% +/- 12.3. Hematological toxicity was not found as the principal dose-limiting toxicity. Severe (grade III/IV) neutropenia was observed only one (4%) patients. No patient was complicated by febrile neutropenia and G-CSF usage was not performed. Grade III and IV anemia were seen in only 4 (15%) and thrombocytopenia was noted only one (4%) patients. Severe hepatic (n = 2) and renal toxicity (n = 1) were observed and these all recovered completely without complication. Several other severe non-hematological side effects were managed easily. Permanent dose reductions were necessary in 9 (33%) patients and chemotherapy administration was also delayed in 7 (26%) patients because of delayed both hematological and non-hematological toxicity recovery. Treatment was discontinued in one (4%) patient due to severe fatigue and deteriorating performance status. In conclusion, gemcitabine and cisplatin combination therapy with this biweekly schedule and dosage is moderately active and extremely safe in patients with metastatic breast cancer previously treated with anthracycline and taxanes.  相似文献   
26.
Summary  In order to investigate the effect of kefir consumption on mucositis induced by 5-FU based chemotherapy (CT), we monitored the systemic immune response by measurement of the serum proinflammatory cytokine levels and we evaluated the anti-microbial effect of kefir with an agar diffusion method. Forty patients with colorectal cancer were included in this randomized prospective study. On the first 5 days of each CT cycle, the study group received oral lavage with kefir and then swallowed 250 ml of kefir while control group received oral lavage with 0.09% NaCl twice a day. Before and after every cycle of CT, the oral mucosa was assessed. Serum proinflammatory cytokine levels were evaluated before the initiation and after the third and the sixth cycle. Kefir was administered in 99 out of 205 courses. Mucositis developed in 27.3% of the courses given with kefir administration and in 21.7% of the courses given with 0.9% NaCl oral rinses. The difference between the two groups was not statistically significant (p > 0.05). When we compared the serum proinflammatory cytokine levels of the two groups at the baseline and following the third and the sixth cycles, we again found no statistically significant difference (p > 0.05). Kefir consumption at the mentioned doses made no statistically significant effect on serum proinflammatory cytokine levels and on the incidence of mucositis development in cancer patients. Under in vitro conditions, kefir inhibits only Staphylococcus epidermidis.  相似文献   
27.
Phosphoinositide 3-kinase α (PI3Kα) is a lipid kinase that plays a key regulatory role in several cellular processes. The mutation or amplification of this kinase in humans has been implicated in the growth of multiple tumor types. Consequently, PI3Kα has become a target of intense research for drug discovery. Our studies began with the identification of benzothiazole compound 1 from a high throughput screen. Extensive SAR studies led to the discovery of sulfonamide 45 as an early lead, based on its in vitro cellular potency. Subsequent modifications of the central pyrimidine ring dramatically improved enzyme and cellular potency and led to the identification of chloropyridine 70. Further arylsulfonamide SAR studies optimized in vitro clearance and led to the identification of 82 as a potent dual inhibitor of PI3K and mTOR. This molecule exhibited potent enzyme and cell activity, low clearance, and high oral bioavailability. In addition, compound 82 demonstrated tumor growth inhibition in U-87 MG, A549, and HCT116 tumor xenograft models.  相似文献   
28.
We report a case of cutaneous rhinosporidiosis localized in the nasal philtrum. The patient's complaints started 3 months prior to being seen in our clinics. Ear, nose, and throat examination showed the presence of a polypoid lesion filling the right nostril. Complete surgical resection of the polypoid lesion provided a temporary relief as the patient developed the same lesion atin 6 weeks post-operation. The appearance and the recurrence pattern have led us to determine whether this lesion was rhinosporidiosis. Histopathological examination confirmed rhinosporidiosis. Finally, we performed complete resection followed by cauterization of the base of the mass. The infection has been reported in hot, tropical climates, and endemic zones of India and Sri Lanka. To our knowledge there is no reported case of rhinosporidiosis from southern Turkey within the subtropical Mediterranean climatic area.  相似文献   
29.
Malignant tumors have a capacity to degrade the extracellular matrix by controlled proteolysis. One system involved in these processes is the urokinase-type plasminogen activator (uPA) system. uPAR levels are elevated in tumors from several types of cancer. Our study was planned to investigate serum and urine levels of uPAR in breast cancer patients (n=180) and healthy controls (n=60) by ELISA. Serum (p<0.001) and urine (p<0.001) uPAR values in the patients were both significantly elevated. High serum and urine levels of uPAR can be used as diagnostic tools in lymph node positive patients.  相似文献   
30.
The objective of this study was to test three measurements: brain stem (BS), intracranial translucency (IT) and brain stem to occipital bone distance (BSOB), as well as one landmark: cisterna magna (CM) visibility, for early diagnosis of open spina bifida (OSB) in a low risk population. A prospective observational study was undertaken in a university hospital. A sample of 1479 women consented to participate between 20 September 2013 and 30 June 2015. Measurements were performed from the mid‐sagittal view, as is routinely used for nuchal thickness assessment. CM visibility was assessed qualitatively as the third anechoic band in the posterior cranial fossa (PCF). All pregnancies were screened with a combination of maternal serum alpha‐fetoprotein and second trimester anomaly scan and followed until delivery. Predictive values were calculated for each marker. We were able to diagnose two OSB cases and highly suspect one Dandy‐Walker malformation case at the first trimester scan by the observation of PCF. PCF characteristics of OSB cases were increased BS diameter, increased BS‐BSOB ratio and non‐visualization of the CM. All the markers demonstrated high sensitivity and specificity but CM visibility reached the highest positive predictive value. Due to relatively high false positive rates, PCF measurements could not reach a satisfactory performance to validate their clinical use as a single marker. CM visibility has the advantage of being a qualitative marker and reduces the need for sophisticated and time‐consuming measurements. Intracranial translucency and BS‐BSOB ratio measurements should be used when the CM visibility is absent or in doubt.  相似文献   
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