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In two previous studies, we observed that recombinant human interleukin- 3 (IL-3) induced an increase in marrow burst-forming unit-erythroid- derived colonies in vitro in some patients with Diamond-Blackfan anemia (DBA). To determine whether a similar erythropoietic response could be induced in vivo, we treated 13 patients with DBA (aged 4 to 19 years) with two preparations of IL-3. All patients had absent absolute reticulocyte counts and markedly reduced to absent recognizable bone marrow erythroid elements; patients with circulating reticulocytes in the previous 12 months were excluded from study. All patients except 1 had failed steroid therapy and had been transfusion-dependent since infancy; 1 patient was maintained on high-dose prednisone at the time of enrollment. On the first arm of the study, IL-3 (Immunex Corp, Seattle, WA) was administered subcutaneously using a dose escalation regimen of 125 to 500 micrograms/m2/day in divided dosage at 12-hour intervals, coadministered with 1.5 mg/kg/d of oral ferrous sulphate. Of the 13 patients that entered the trial, 4 stopped prematurely because of adverse side effects. In the other 9 evaluable cases, reticulocytes increased transiently in 1 patient from 0 to 65 x 10(9)/L after 35 days of IL-3 therapy at 250 micrograms/m2, but transfusion dependency persisted. One transient peak in absolute reticulocyte count was noted in 6 other patients, but no erythroid response was observed after completion of a full course of IL-3. Oral prednisone at 0.5 mg/kg/d was then coadministered with IL-3 at 500 micrograms/m2 to 5 of the patients without effect, and treatment was stopped. In 2 patients, a second preparation of IL-3 (Sandoz Canada Inc, Dorval, Quebec, Canada) was initiated in a dose escalation regimen of 2.5 to 10 micrograms/kg and was coadministered with ferrous sulphate. No erythroid response was observed in either patient, and in one of the two, alternate-day subcutaneous recombinant erythropoietin at 300 U/kg was administered for 3 weeks in combination with daily IL-3 at 10 micrograms/kg, but no increased erythropoiesis was seen. Significant increases in white blood cell and eosinophil counts during administration of both preparations of IL-3 were observed in all patients. These data show that the response of DBA patients to IL-3 in vivo is heterogeneous and cannot be predicted from in vitro studies. The absence of a corrective effect of IL-3 in these patients with DBA indicates that a deficiency of the cytokine is not central in the pathogenesis of the disorder.  相似文献   
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Bressler B  Pinto R  El-Ashry D  Heathcote EJ 《Gut》2005,54(3):407-410
BACKGROUND: Recent guidelines from an AASLD Single Topic Symposium suggest that patients with cirrhosis, including those with primary biliary cirrhosis (PBC) or primary sclerosing cholangitis (PSC), should be screened for oesophageal varices when the platelet count is <140,000/mm3. AIM: To determine the validity of these guidelines in clinical practice in patients with PBC or PSC. METHODS: Retrospective review of individuals undergoing screening upper endoscopy for oesophageal varices at a single centre. Oesophageal varices were reported as being present or absent. RESULTS: A total of 235 patients with chronic liver disease, including 86 patients with PBC (n=79) or PSC (n=7), 104 patients with chronic viral hepatitis, and 45 with non-alcoholic cirrhosis of differing aetiologies, underwent a single screening endoscopy between 1996 and 2001. Oesophageal varices were detected in 26 (30%) of the PBC/PSC group, 38 (37%) of the viral hepatitis group, and 21 (47%) of the "other" group. Applying multiple logistic regression analysis to the data in the group with PBC/PSC, platelets <200,000/mm3 (odds ratio (OR) 5.85 (95% confidence interval (CI) 1.79-19.23)), albumin <40 g/l (OR 6.02 (95% CI 1.78-20.41)), and serum bilirubin >20 micromol/l (OR 3.66 (95% CI 1.07-12.47)) were shown to be independent risk factors for oesophageal varices. Prothrombin time was unhelpful. The values at these cut offs were not useful in predicting oesophageal varices in the other groups. CONCLUSION: We conclude that current guidelines recommended by the AASLD Single Topic symposium are invalid in our cohort of patients with PBC and PSC. Patients with a platelet count <200,000/mm3, an albumin level <40 g/l, and a bilirubin level >20 micromol/l should be screened for oesophageal varices.  相似文献   
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BACKGROUNDThere has been an increase in cases of inflammatory bowel disease (IBD) in recent years. There is also greater access and availability of immunosuppressive and biological agents, which increase the risk of opportunistic infection despite improving the quality of life and promoting mucosal healing. Tuberculosis (TB) remains a public health problem, and it has a high incidence in several countries. Therefore, knowledge of the risk of developing TB in patients with IBD is important.AIMTo evaluate the risk of active TB in patients with IBD under treatment from an endemic area in Latin America.METHODSA standard questionnaire included demographic variables, clinical aspects of IBD disease, history of active TB during treatment, active TB characteristics and evolution, initial screening and results and time from the start of anti-tumor necrosis factor alpha (TNFα) to TB development.RESULTSAzathioprine, anti-TNFα and the combination of these two drugs were associated with a higher risk of active TB incidence. The TNFα blockers increased the relative risk of developing active TB compared to other treatments. All four multivariable models showed that the use of TNFα blockers alone or in combination with azathioprine was an important risk factor for the incidence of active TB. After adjustment for sex, age, type of IBD and latent TB, anti-TNFα with azathioprine increased the relative risk to 17.8 times more than conventional treatment. Late TB, which was diagnosed 3 mo after the start of anti-TNFα, was the most frequent.CONCLUSIONTreatment with anti-TNFα increased the risk of active TB in IBD patients from an endemic area in Latin America. This risk was increased when anti-TNFα was combined with azathioprine. The time from the beginning of the treatment to the active TB diagnosis suggests a new TB infection.  相似文献   
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Abstract: The prevalence of Parkinson’s disease (PD) is expected to double over the next 20 years owing to the increase in life expectancy. This progressive disease has several implications relating to oral health, and many are manageable with proper awareness and knowledge about the disease. This article reviews the epidemiology, pathophysiology, and characteristics of PD, as well as the treatments and oral health considerations to enable dental hygienists to undertake an informed approach to patient management strategies and provide optimal care.  相似文献   
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