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991.
The antacid ES Riopan was acidified ex vivo to pH 2.5 to completely eliminate its buffering capacity and was then tested as a mucosal protective agent. The pH 2.5 acidified antacid solution was named activated aluminum complex. Activated aluminum complex was 8.2 times more potent than its parent antacid in protecting against acidified aspirin-induced gastric lesions in the rat. Activated aluminum complex had a duration of action greater than 10 h in the ethanol-induced gastric lesion model, while ES Riopan was active for 6 h. Activated aluminum complex was able to inhibit both acid- and nonacid-mediated ulcers in the stomach and intestine. Its mucosal protective activity was not blocked by pretreatment with indomethacin. These results demonstrate that the nonbuffering antacid activated aluminum complex exerted a more potent and longer-lasting mucosal protective activity than its parent antacid. The activity was probably due to the presence of a hexaaquoaluminum cation and supports the argument that antacids possess mucosal protective effects independent of their acid-neutralizing capacity. 相似文献
992.
Non-01 Vibrio cholerae infections in Cancun, Mexico 总被引:6,自引:0,他引:6
M J Finch J L Valdespino J G Wells G Perez-Perez F Arjona A Sepulveda D Bessudo P A Blake 《The American journal of tropical medicine and hygiene》1987,36(2):393-397
To determine the role of Vibrio cholerae as a cause of diarrheal illness in Cancun, Mexico, an investigation was conducted in July and August 1983. Although toxigenic V. cholerae 01 were not found, non-01 V. cholerae were isolated from 22 (16%) of 134 stools from persons with diarrheal illness and none of 22 stools from well persons; 58 (92%) of 63 sewage samples; 12 (86%) of 14 untreated well water samples; a home storage tank for treated water; and 5 (21%) of 24 samples of raw seafood. None of the V. cholerae isolates from patients were toxigenic. The illness occurred mainly in small children, and were characterized principally by diarrhea and abdominal pain. No patient was seriously ill, and all recovered without sequelae. Seven different serotypes of non-01 V. cholerae were isolated from the stool specimens, and Smith serotype 12 accounted for 10 (46%) of the 22 isolates. A matched-pair case-control study found that cases were more likely than controls to have eaten home prepared gelatin (P = 0.03, OR = 5/0) and seafood (P = 0.06, OR = 4/0). 相似文献
993.
P Dewan A Sosnovskaja V Thomsen J Cicenaite K Laserson I Johansen E Davidaviciene C Wells 《The international journal of tuberculosis and lung disease》2005,9(2):170-174
BACKGROUND: Nations of the former Soviet Union have the world's highest reported levels of resistance to anti-tuberculosis drugs. We conducted the first national survey of anti-tuberculosis drug resistance in the Republic of Lithuania. METHODS: We tested Mycobacterium tuberculosis isolates from all incident culture-positive pulmonary TB patients registered in 2002. New patients were those treated for <1 month with any first-line anti-tuberculosis drug (isoniazid [INH], rifampin [RMP], ethambutol, or streptomycin); previously treated patients were those treated for > or =1 month. RESULTS: Of 1163 isolates, 475 (41%) were resistant to at least one first-line drug, and 263 (23%) were resistant to at least INH and RMP (MDR); this included 76/818 (9.3%) from new patients and 187/345 (54%) from previously treated patients. Of 52 MDR isolates randomly selected for extended testing at an international reference laboratory, 27 (51%, 95%CI 38-66) had resistance to pyrazinamide, 21 (40%, 95%CI 27-55) to kanamycin, and 9 (17%, 95%CI 8-30) to ofloxacin. CONCLUSIONS: The prevalence of MDR-TB in Lithuania is among the world's highest. Among MDR-TB isolates, aminoglycoside and fluoroquinolone resistance were common. To combat drug-resistant TB, Lithuania has implemented the WHO global TB control strategy (DOTS), and is developing an MDR-TB treatment program (DOTS-Plus). 相似文献
994.
995.
996.
Spagnolo P Sato H Grunewald J Brynedal B Hillert J Mañá J Wells AU Eklund A Welsh KI du Bois RM 《Journal of internal medicine》2008,264(5):433-441
Aim. Sarcoidosis is a heterogeneous disorder with a strong genetic influence. Genetic factors are also thought to influence disease severity and outcome. We sought to determine whether polymorphisms within CCR2 gene predispose to Löfgren’s syndrome – a clinically and genetically distinct sarcoidosis phenotype – and, importantly, whether this association is independent of the known association with the HLA‐DRB1*0301 allele. Methods. We investigated 5 CCR2 variants and HLA‐DRB1*0301 by sequence‐specific primer (SSP) polymerase chain reaction (PCR) in 176 Spanish (76 Löfgren’s syndrome, 100 controls) and 387 Swedish subjects (126 Löfgren’s syndrome, 77 non‐Löfgren sarcoidosis, 184 controls). Results. One of the deduced haplotypes (CCR2 haplotype 2) was associated with Löfgren’s syndrome in both Spanish (OR: 2.03, uncorrected P = 0.02; permuted P = 0.041 vs. controls) and Swedish patients (OR: 3.02, uncorrected P = 0.0007; permuted P = 0.0027 vs. non‐Löfgren sarcoidosis; OR: 2.46, uncorrected P = 0.0005; permuted P = 0.0031 vs. controls). HLA‐DRB1*0301 allele frequency was also increased in Spanish (OR: 3.52, P = 0.0004 vs. controls) and Swedish patients with Löfgren’s syndrome (OR: 10.98, P < 0.0001 vs. non‐Löfgren sarcoidosis, OR: 7.71, P < 0.0001 vs. controls). Finally, multivariate analysis revealed that the CCR2 association was independent of HLA‐DRB1*0301 in both Spanish (P = 0.02 vs. controls) and Swedish cohorts (P = 0.002 vs. non‐Löfgren sarcoidosis, P = 0.001 vs. controls). Conclusions. This study confirms that CCR2 haplotype 2 and HLA‐DRB1*0301 are independent genetic risk factors for Löfgren’s syndrome. 相似文献
997.
Sepsis is a common cause of morbidity and mortality. Neutrophils are the major defense against bacterial invasion, and granulocyte colony- stimulating factor (G-CSF) augments both neutrophil number and function. In our study, 160 rabbits were inoculated transtracheally with 0.5 mL of a solution containing 10(4) colony forming units per milliliter of Pasteurella multocida. Twenty-four hours later, chest x- rays and quantitative blood cultures demonstrated pneumonia and bacteremia. Therapy was then begun with penicillin G and either recombinant human G-CSF (rG-CSF; 5 to 8 micrograms/kg subcutaneously) or placebo every day for 5 days. Arterial blood gases and 23 other parameters of organ function were performed before inoculation and serially thereafter. All rabbits underwent histologic examination of organs at the time of septic death or when sacrificed on day 6. A total of 149 rabbits survived long enough to initiate therapy. A significant increase in leukocytes by day 4 was found in the rG-CSF-treated group. There was a trend towards improved survival in the rG-CSF group (77% v 67%; P = .13, n = 149). Analysis of pretreatment variables revealed sepsis-induced leukopenia (< or = 2,800/microL) as the only predictor of significantly improved survival with rG-CSF treatment (57% v 39%; P = .04, n = 73). The majority of the survival benefit occurred within the first 24 hours of treatment. This was before the time that a significant difference in mean white blood cell (WBC) count was observed between the study groups, making intravascular leukocytosis an unlikely explanation for the survival advantage in the rG-CSF group. No significant difference in laboratory variables reflecting organ function was demonstrated between the groups. Histologic grading of inflammation (0, normal, to 6, necrosis) in seven organs revealed that the surviving rabbits had mild but statistically significant increased inflammation in the liver, spleen, and noninoculated lung in the rG-CSF versus placebo groups (liver: 2.6 v 1.5, P < or = .0001; spleen: 3.2 v 2.3, P < or = .0001; and noninoculated lung: 2.9 v 2.5, P = .04). Administration of rG-CSF, in addition to penicillin G, in immune competent rabbits with gram-negative sepsis complicated by leukopenia significantly improved survival over antibiotics alone. The administration of rG-CSF in early sepsis for a short therapeutic duration was not associated with any clinically evident toxicity. Clinical trials using rG-CSF in septic patients with leukopenia are indicated. 相似文献
998.
Thompson BF Fry LC Wells CD Olmos M Lee DH Lazenby AJ Mönkemüller KE 《Gastrointestinal endoscopy》2004,59(7):906-910
BACKGROUND: The aim of this study was a detailed endoscopic-pathologic assessment of patients with various forms of GI strongyloidiasis. METHODS: Six patients with a diagnosis of GI strongyloidiasis who underwent endoscopic evaluation during a 3-year period (January 1998-January 2001) were included. Published information was reviewed in detail, focusing on the endoscopic features and the diagnostic approach to this parasitosis. OBSERVATIONS: Strongyloidiasis has a broad range of endoscopic features. In the duodenum, the findings included edema, brown discoloration of the mucosa, erythematous spots, subepithelial hemorrhages, and megaduodenum. In the colon, the findings included loss of vascular pattern, edema, aphthous ulcers, erosions, serpiginous ulcerations, and xanthoma-like lesions, and, in the stomach, thickened folds and mucosal erosions. A histopathologic diagnosis of strongyloidiasis was made in all cases. CONCLUSIONS: Strongyloidiasis can involve any segment of the GI tract. EGD with procurement of biopsy specimens from the duodenum was the most accurate method of diagnosis in this case series. 相似文献
999.
Extended outpatient therapy with low molecular weight heparin for the treatment of recurrent venous thromboembolism despite warfarin therapy 总被引:5,自引:0,他引:5
PURPOSE: The optimal management of patients who have recurrent thromboembolism while being treated with oral anticoagulation therapy is unknown. This study reports managing such patients with extended duration low molecular weight heparin therapy. SUBJECTS AND METHODS: This study was a retrospective review of the prospective databases of three tertiary care teaching hospitals over a 27-month period. All patients who had recurrent symptomatic thromboembolism while being treated with warfarin were identified. All patients were treated with low molecular weight heparin (dalteparin), 200 U/kg daily. Data were collected for recurrent venous thromboembolism, bleeding, and survival. RESULTS: Eight hundred eighty-seven patients were managed for acute thromboembolism. In 32 patients, symptomatic, objectively documented thromboembolism recurred while they were taking warfarin; 63% of the patients with recurrence had cancer, compared with 30% of patients without recurrence. All recurrences were treated with dalteparin. In 3 patients (9% [95% confidence interval: 2% to 25%]), symptomatic recurrence developed while they were being treated with low molecular weight heparin. Nineteen patients (59%) died while receiving anticoagulation therapy; all deaths but 1 were due to malignancy, and none was due to pulmonary embolism or bleeding. CONCLUSIONS: These results suggest that recurrent venous thromboembolism is more likely to develop in cancer patients while being treated with warfarin and that long-term therapy with low molecular weight heparin may be effective in managing warfarin-failure thromboembolic disease. 相似文献
1000.
Gilbert's syndrome occurs in 5%-7% of the human population and is caused by an inherited deficiency in the glucuronidation of endogenous bilirubin, resulting in its accumulation and jaundice. The authors of the present study have previously shown that rats with a similar deficiency in bilirubin glucuronidation (Gunn rats) had reduced glucuronidation and enhanced susceptibility to the toxicity of the widely used analgesic, acetaminophen. Acetaminophen is eliminated primarily by glucuronidation, which prevents its cytochrome P-450-catalysed bioactivation to a hepatotoxic reactive intermediate. The purpose of this study was to determine whether people with Gilbert's syndrome had reduced glucuronidation and enhanced bioactivation of acetaminophen. Therefore, the biotransformation of acetaminophen, 20 mg/kg IV, was investigated in six subjects with Gilbert's syndrome (total bilirubin, 41 +/- 6 mumol/L; mean +/- SE) and six normal controls (total bilirubin, 11 +/- 2 mumol/L; P less than 0.01). Formation of the acetaminophen glucuronide conjugate measured by high-performance liquid chromatography was quantified by the ratio of the area under the plasma concentration-time curve (AUC) from 0 to 2 hours for the acetaminophen glucuronide divided by the AUC for acetaminophen. Acetaminophen bioactivation was quantified by the molar percentage of acetaminophen excreted in the urine during 24 hours as glutathione-derived conjugates (cysteine and mercapturic acid). Acetaminophen glucuronide formation in subjects with Gilbert's syndrome was 31% lower than that in normal controls (0.27 +/- 0.05 vs. 0.39 +/- 0.03; P less than 0.05), and bioactivation was 1.7-fold higher (3.5% +/- 0.4% vs. 2.1% +/- 0.3%; P less than 0.05). One control subject with normal bilirubin glucuronidation had substantially decreased acetaminophen glucuronide formation (0.20) and enhanced bioactivation (4.8%). Among all subjects, glucuronidation correlated inversely with bioactivation (r = -0.84; P less than 0.001), indicating that a decrease in a major pathway of elimination can shunt more drug through the toxifying route. Thus, a deficiency in bilirubin UDP-glucuronosyltransferase, evidenced by jaundice, can be paralleled by a deficiency in glucuronidation of other compounds. In these cases, jaundice can be a phenotypic determinant of enhanced acetaminophen bioactivation. On the other hand, some people with normal bilirubin glucuronidation may have a deficiency in the glucuronidation of acetaminophen; these people are not easily recognized.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献