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61.
IL-23 and IL-17 in the establishment of protective pulmonary CD4+ T cell responses after vaccination and during Mycobacterium tuberculosis challenge 总被引:10,自引:0,他引:10
Khader SA Bell GK Pearl JE Fountain JJ Rangel-Moreno J Cilley GE Shen F Eaton SM Gaffen SL Swain SL Locksley RM Haynes L Randall TD Cooper AM 《Nature immunology》2007,8(4):369-377
Interferon-gamma is key in limiting Mycobacterium tuberculosis infection. Here we show that vaccination triggered an accelerated interferon-gamma response by CD4(+) T cells in the lung during subsequent M. tuberculosis infection. Interleukin 23 (IL-23) was essential for the accelerated response, for early cessation of bacterial growth and for establishment of an IL-17-producing CD4(+) T cell population in the lung. The recall response of the IL-17-producing CD4(+) T cell population occurred concurrently with expression of the chemokines CXCL9, CXCL10 and CXCL11. Depletion of IL-17 during challenge reduced the chemokine expression and accumulation of CD4(+) T cells producing interferon-gamma in the lung. We propose that vaccination induces IL-17-producing CD4(+) T cells that populate the lung and, after challenge, trigger the production of chemokines that recruit CD4(+) T cells producing interferon-gamma, which ultimately restrict bacterial growth. 相似文献
62.
63.
David RH Christie Kenneth W Tiver 《Journal of Medical Imaging and Radiation Oncology》1996,40(3):331-333
Five patients who received radiotherapy (RT) for 7 melanotic freckles (MF, also known as Hutchinson's freckles, lentigo maligna) were reviewed 8 to 37 months after their treatment by RT. Local control and a favourable cosmetic result occurred in all patients. Treatment toxicity was minimal. Few reports about the use of RT for MF exist. Many other treatments including observation alone have been associated with high rates of recurrence, and in some cases conversion to invasive melanoma has occurred. RT appears to be a safe and effective treatment for this condition, providing that doses equivalent to 44 Gy in 11 fractions or more are given. 相似文献
64.
Two hundred and fifty three infants were screened for cytomegalovirus (CMV) in the urine at birth and were followed up at regular intervals for one year. Twelve per cent (of 249) were excreting virus at 3 months, and 20% (of 234) at 12 months. In all cases infection was subclinical. The major factors determining risk of acquiring infection were the mother''s serological state and whether the infant was breast fed. There was no association with social class, mother''s age, or whether the child had been in a special care baby unit or a postnatal ward. By one year 33% (of 123) of infants of seropositive mothers had acquired CMV infection compared with 4% (of 123) born to seronegative mothers. Twenty per cent (17) of seropositive women who breast fed had virus isolated from their breast milk on at least one occasion, and 76% (13) of their infants became infected. In four mother-infant pairs comparison of CMV isolates from the mother''s milk and the child''s urine was made by restriction endonuclease digestion; in each pair infection had apparently occurred with the same strain of virus. All 13 infected infants followed up for three years were still shedding virus. Infection with CMV is common in infancy, and virus shedding persists for years. Congenital infection cannot be distinguished from acquired infection unless the presence of CMV in the urine is identified within three or four weeks after birth, even when clinical problems suggestive of congenital infection are present. 相似文献
65.
66.
Idiopathic CD4+T-cell lymphocytopenia associated with vitiligo 总被引:3,自引:0,他引:3
The syndrome of idiopathic CD4+ T lymphocytopenia (ICTL) is defined as the persistent depletion of peripheral blood CD4+ T lymphocytes below 300 cells/mm(3) or less than 20% of the total lymphocytes in the absence of either HIV infection or other known causes of immunodeficiency. To date no known viral origin has been identified. ICTL has a variable clinical course ranging from patients with minimal symptoms to those who have died from opportunistic infections. We report a case of a 32-year-old white man with a long history of vitiligo that is associated with ICTL. He also had incidental psoriasis. The correlation between ICTL and autoimmune vitiligo suggests an aberration in the immune surveillance that leads to an abnormal response of CD4+ T lymphocytes in the host. 相似文献
67.
Efficacy of recombinant human erythropoietin in critically ill patients: a randomized controlled trial 总被引:11,自引:0,他引:11
Corwin HL Gettinger A Pearl RG Fink MP Levy MM Shapiro MJ Corwin MJ Colton T;EPO Critical Care Trials Group 《JAMA》2002,288(22):2827-2835
Context Anemia is common in critically ill patients and results in a large number of red blood cell (RBC) transfusions. Recent data have raised the concern that RBC transfusions may be associated with worse clinical outcomes in some patients. Objective To assess the efficacy in critically ill patients of a weekly dosing schedule of recombinant human erythropoietin (rHuEPO) to decrease the occurrence of RBC transfusion. Design A prospective, randomized, double-blind, placebo-controlled, multicenter trial conducted between December 1998 and June 2001. Setting A medical, surgical, or a medical/surgical intensive care unit (ICU) in each of 65 participating institutions in the United States. Patients A total of 1302 patients who had been in the ICU for 2 days and were expected to be in the ICU at least 2 more days and who met eligibility criteria were enrolled in the study; 650 patients were randomized to rHuEPO and 652 to placebo. Intervention Study drug (40 000 units of rHuEPO) or placebo was administered by subcutaneous injection on ICU day 3 and continued weekly for patients who remained in the hospital, for a total of 3 doses. Patients in the ICU on study day 21 received a fourth dose. Main Outcome Measures The primary efficacy end point was transfusion independence, assessed by comparing the percentage of patients in each treatment group who received any RBC transfusion between study days 1 and 28. Secondary efficacy end points identified prospectively included cumulative RBC units transfused per patient through study day 28; cumulative mortality through study day 28; change in hemoglobin from baseline; and time to first transfusion or death. Results Patients receiving rHuEPO were less likely to undergo transfusion (60.4% placebo vs 50.5% rHuEPO; P<.001; odds ratio, 0.67; 95% confidence interval [CI], 0.54-0.83). There was a 19% reduction in the total units of RBCs transfused in the rHuEPO group (1963 units for placebo vs 1590 units for rHuEPO) and reduction in RBC units transfused per day alive (ratio of transfusion rates, 0.81; 95% CI, 0.79-0.83; P = .04). Increase in hemoglobin from baseline to study end was greater in the rHuEPO group (mean [SD], 1.32 [2] g/dL vs 0.94 [1.9] g/dL; P<.001). Mortality (14% for rHuEPO and 15% for placebo) and adverse clinical events were not significantly different. Conclusions In critically ill patients, weekly administration of 40 000 units of rHuEPO reduces allogeneic RBC transfusion and increases hemoglobin. Further study is needed to determine whether this reduction in RBC transfusion results in improved clinical outcomes. 相似文献
68.
Neil A. Abrahams Thomas V. Colby Richard H. Pearl Bradley E. Chipps Andrew L. Juris Kevin O. Leslie 《Pediatric and developmental pathology》2002,5(3):283-292
Pulmonary hemangiomas are exceptionally rare in childhood and more so in infancy. They may involve the airways or the parenchyma,
and may be localized or multifocal. We present two cases of pulmonary capillary hemangiomas. The first case is a localized
form of capillary hemangioma that was resected from an 8-week-old infant with signs of respiratory distress. A computed tomography
scan showed a cystic mass initially thought to be an intrapulmonary bronchogenic cyst. A segmental resection was performed
and examination revealed a localized capillary hemangioma without cystic or cavernous features. The second case is an example
of a multifocal capillary hemangioma from a 9-year-old child who presented clinically with clubbing of fingers and toes and
radiologically had multiple discrete nodules localized to the right lung. The clinical and pathological features of the cases
are discussed together with a review of the literature. The distinction from other vascular neoplasms of childhood is briefly
described. Although rare, pulmonary hemangiomas should be entertained in the diagnosis of both solid and cystic intrapulmonary
lesions of childhood and infancy.
Received September 6, 2001; accepted November 13, 2001. 相似文献
69.
Endothelin receptor blockade reduces ventricular dysfunction and injury after reoxygenation 总被引:6,自引:0,他引:6
Pearl JM Nelson DP Wagner CJ Lombardi JP Duffy JY 《The Annals of thoracic surgery》2001,72(2):565-570
BACKGROUND: Reoxygenation of hypoxic myocardium during repair of congenital heart defects results in poor ventricular function and cellular injury. Endothelin-1 (ET-1), a potent vasoconstrictor that increases during hypoxia, may suppress myocardial function and activate leukocytes. The objective was to determine whether administration of an endothelin receptor antagonist could improve ventricular function and decrease cardiac injury after hypoxia and reoxygenation. METHODS: Fourteen piglets underwent 90 minutes of ventilator hypoxia, 1 hour of reoxygenation on cardiopulmonary bypass, and 2 hours of recovery (controls). Nine additional animals received an infusion of Bosentan, an ET(A/B) receptor antagonist, (5 mg/kg per hour) during hypoxia and reoxygenation. RESULTS: Right and left ventricular dP/dt in controls decreased to 78% and 52% of baseline, respectively, after recovery (p < 0.05). In contrast, Bosentan-treated animals had complete preservation of RV dP/dt and less depression of LV dP/dt. Bosentan reduced the hypoxia and reoxygenation-induced elevation of ET-1 and iNOS mRNA at the end of recovery (p < 0.05). Bosentan-treated animals had diminished myocardial myeloperoxidase activity and lipid peroxidation compared with controls (p < 0.05). Myocardial apoptotic index, elevated by hypoxia and reoxygenation, was lower in the Bosentan-treated animals (p < 0.05). CONCLUSIONS: Endothelin-1 receptor antagonism improved functional recovery and decreased leukocyte-mediated injury after reoxygenation. The reduction in cardiac cell death might also improve long-term outcome after reoxygenation injury. 相似文献
70.
Cintron JR Park JJ Orsay CP Pearl RK Nelson RL Sone JH Song R Abcarian H 《Diseases of the colon and rectum》2000,43(7):944-9; discussion 949-50