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Patients with acquired immunodeficiency syndrome (AIDS) and persistent lymphadenopathy syndrome (LAS) display significant hematological abnormalities of one or more cell lineages. In order to understand the pathophysiologic mechanisms leading to these abnormalities we studied the proliferation capacity of pluripotent and committed hemopoietic precursors using in-vitro colony assays. Anemia, leukopenia and thrombopenia were relatively frequent findings in HIV-infected subjects irrespectively of the patients' clinical status. The colony growth capacity of AIDS patients' GM-CFU and BFU-E was significantly decreased whereas no GEMM-CFU colonies could be obtained. There was no correlation between the number of BFU-E and GM-CFU colony number and the hemoglobin or the absolute number of polynuclear cells, respectively. The plating efficiency of both committed and pluripotent hematopoietic precursors from HIV infected patients could not be enhanced when additional exogenous recombinant GM-CSF, human interleukin 3 or erythropoietin were added in contrast to normal patients' cells. In addition, the impaired colony growth of these precursors could not be restored after adherent or T-cell depletion or the addition of normal allogenic irradiated adherent or/and T cells. Since this colony growth abnormality was also detected in HIV seropositive asymptomatic subjects our findings strongly suggest that the in-vitro growth of hematopoietic precursors is affected early after HIV-1 infection.  相似文献   
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We studied a Cuban family with presenile dementia (autosomal dominant) consisting of 281 members within six generations, the proband descended from a Spanish founder. Mean age at onset was 59 years of age. Memory impairment was the main symptom in all patients, additionally, ischemic episodes were described in 4 (n=18) patients. Neuropathological examination of brain material (1 patient) revealed neuronal loss, amyloid plaques, and neurofibrillary tangles. Thirty DNA samples were genotyped (regions on chromosome 1, 3, 10, 12, 14, 17, 19, 20, and 21). A maximum Lod score of 3.79 at θ=0 was obtained for marker D14S43, located in a 9-cM interval in which all patients shared the same haplotype. Sequencing of the PSEN1 gene revealed a heterozygous base substitution, C520A (exon 6), which is predicted to cause an amino acid change from leucine to methionine in the TMIII of the presenilin 1 protein. The mutation was found to co-segregate with the disease phenotype and the associated disease haplotype. The C→A change was not observed in 80 control chromosomes from the Cuban population. Leucine at position 174 is highly conserved among species and is identical in presenilin 1 and presenilin 2 proteins. We propose the L174 M mutation might lead to an abnormal N-terminal and probably C-terminal fragments and malfunction of the protein complex. In conclusion, we found a novel PSEN1 mutation in a large family with clinical and pathological diagnosis of early onset familial Alzheimer disease, which may be relevant for other Hispanic populations. Electronic Publication  相似文献   
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PURPOSE: This collaborative study by three Italian groups of child neuropsychiatrists was carried on to evaluate the efficacy and safety of the classic 4:1 ketogenic diet as add-on treatment in refractory partial or generalized epilepsy in children, adolescents and young adults. METHODS: We performed a prospective add-on study in 56 refractory epilepsy young patients (age 1-23 years, mean 10.4 years), all with both symptomatic and cryptogenic, generalized or partial epilepsies. Child neuropsychiatrists worked with nutritional team for sample selection and patients management. The ketogenic diet was added to the baseline antiepileptic drugs and the efficacy was rated according to seizure type and frequency. During treatment, seizure frequency, side effects, urine and blood ketone levels and other parameters were systematically evaluated. RESULTS: Patients have been treated for 1-18 months (mean 5 months). A >50% reduction in seizure frequency was gained in 37.5 and 26.8% of patients after 3 and 6 months, respectively, at 12 months, this number fell by 8.9%. No significant relationship between diet efficacy and seizure or epilepsy type, age at diet onset, sex and etiology of epilepsy was noted. Nevertheless, it seems noteworthy that 64% of our patients with neuronal migration disorders improved on this diet. Adverse effects occurred, mainly in the first weeks of treatment, in 32 patients (57.1%), but were generally mild and transient. In seven patients (12.5%) it was possible to withdraw one to two AED after 3-4 months on ketogenic diet. CONCLUSION: This initial experience with the ketogenic diet was effective in difficult-to-treat patients with partial and generalized epilepsies, though its efficacy dropped significantly by 9-12 months.  相似文献   
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BACKGROUND: This pivotal phase III trial evaluated the efficacy and safety of palonosetron in preventing acute and delayed chemotherapy-induced nausea and vomiting (CINV) following highly emetogenic chemotherapy (HEC). PATIENTS AND METHODS: Patients were randomized to a single intravenous dose of palonosetron 0.25 mg or 0.75 mg, or ondansetron 32 mg prior to HEC. Dexamethasone pre-treatment (with stratification) was used at investigator discretion. The primary efficacy endpoint was the proportion of patients with complete response (CR) during the first 24 h post-chemotherapy (acute phase). RESULTS: In the intent-to-treat analysis (n = 667), palonosetron 0.25 mg and 0.75 mg were at least as effective as ondansetron in preventing acute CINV (59.2%, 65.5%, and 57.0% CR rates, respectively); CR rates were slightly higher with palonosetron than ondansetron during the delayed (24-120 h) and overall (0-120 h) phases. Two thirds of patients (n = 447) received concomitant dexamethasone. Patients pre-treated with palonosetron 0.25 mg plus dexamethasone had significantly higher CR rates than those receiving ondansetron plus dexamethasone during the delayed (42.0% versus 28.6%) and overall (40.7% versus 25.2%) phases. Palonosetron and ondansetron were well tolerated. CONCLUSIONS: Single-dose palonosetron was as effective as ondansetron in preventing acute CINV following HEC, and with dexamethasone pre-treatment, its effectiveness was significantly increased over ondansetron throughout the 5-day post-chemotherapy period.  相似文献   
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Background The cause of cancer in the gastric stump is multifactorial, and Helicobacter pylori is one of these factors. Its eradication has been recommended; however, there are few studies about of H. pylori eradication in gastrectomized patients. Methods Twenty gastrectomized patients with gastric adenocarcinoma and Roux-en-Y reconstruction (study group) infected by H. pylori were compared with nongastrectomized patients (control group) also infected by H. pylori. The presence of H. pylori was determined by the ultra-quick urease test and from a histological sample obtained by endoscopy. Both groups received the same triple therapy regimen. Results The rate of eradication of H. pylori in the study group was 90% and in the control group, it was 85%. Sex, age, and postoperative time did not influence the rate of eradication. Conclusion There were no differences in the efficacy of H. pylori eradication between the two groups; therefore, the triple therapy regimen is effective for the eradication of H. pylori in gastrectomized patients with a Roux-en-Y reconstruction.  相似文献   
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Ainhum (dactolysis spontanea) is most frequently seen involving the fifth toes of black men. An atypical case involving the second toes bilaterally in a white male is presented. The differential diagnosis, radiological findings and pathological appearance of this rare entity are discussed.  相似文献   
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The presence of yeasts on the hands of 86 healthy hosts (62 hospital workers and 24 healthy members of the community with no hospital exposure) was investigated. A high rate of colonization was found (59.3%). Candida parapsilosis was the most frequently isolated species (51%), independent of the origin of the samples. The potential virulence and resistance to antifungals of the 26 C. parapsilosis isolates were determined. All were proteinase producers and formed biofilms. The haemolytic activity was variable, with a predominance of total haemolysis of sheep erythrocytes. All isolates were susceptible to amphotericin B but two showed reduced susceptibility to fluconazole. Healthy people may be colonized by a species of yeast with a high capacity for adhesion to plastic surfaces, providing an infection risk to susceptible individuals.  相似文献   
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