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OBJECTIVE: Immunosuppressive regimens for rejection after heart transplantation have been modified to reduce infectious complications without diminishing rejection treatment efficacy. A review of a single institutional series was performed to evaluate the influence of conservative management of grade 2 rejection on long-term outcomes after heart transplantation. METHODS: Before 1990, patients with late (>3 months after transplant) grade 2 rejection were treated with supplemental immunosuppressive drugs. Beginning in 1990, patients with late grade 2 rejection were treated conservatively by maintaining the current immunosuppressive regimen without additional therapy. The groups were compared for survival, incidence of subsequent rejection, and incidence of subsequent infection. RESULTS: One hundred twelve patients had one or more episodes of isolated, late grade 2 rejection; 39 (35%) were treated with supplemental immunosuppression (treated group) and 73 (65%) received no additional therapy (nontreated group). The mean time from transplantation to the first episode of isolated grade 2 rejection was 15.6 months in the treated group and 17.8 months in the nontreated group. Graft survival at 5 and 10 years was 69% and 51 %, respectively, in the treated group and 67% and 41 %, respectively, in the nontreated group (p = 0.77). The rates for overall subsequent rejection were 0.031 episodes/patient-month in the treated group and 0.029 episodes/patient-month in the nontreated group (p = 0.64). The rates for early rejection within 6 months of initial grade 2 rejection were 0.044 episodes/patient-month in the treated group and 0.035 episodes/patient-month in the nontreated group (p = 0.56). The rates for overall subsequent infection were 0.018 episodes/patient-month in the treated group and 0.012 episodes/patient-month in the nontreated group (p = 0.05). The rates for early infection within 6 months of initial grade 2 rejection were 0.070 episodes/patient-month in the treated group and 0.032 episodes/patient-month in the nontreated group (p = 0.04). Group comparisons demonstrated a significantly lower incidence of infection in the nontreated group. CONCLUSIONS: Conservative management of late grade 2 rejection neither adversely affects survival nor increases the incidence of subsequent short-term or long-term rejection. This approach lowers the early and late incidence of infection after rejection and may reduce other complications from aggressive supplemental immunosuppression.  相似文献   
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OBJECTIVE: To compare elastase concentrations in gingival crevicular fluid (GCF) from individual sites of smokers and non-smokers.
MATERIALS AND METHODS: Twelve pairs of smokers and non-smokers with untreated, moderate to advanced chronic inflammatory periodontal disease were matched for gender, age, ethnicity and the clinical and radio-graphic extent of disease. Durapore filter strip samples were collected over 30 s from two mesiopalatal sites on upper left posterior teeth. Samples were analysed for: I) polymorphonuclear neutrophil leucocyte (PMNL) cell counts; 2) PMNL elastase-αI-antitrypsin complex in the GCF supernatant by ELISA; and 3) functional elastase, free or bound to α2-macroglobulin, estimated from activity against N-tert-butoxycarbonyI-alanyl-prolyl-nor-valylg-chlorothiobenzyl ester in supernatant and lysates of GCF PMNLs.
RESULTS: There were no differences in disease parameters between groups except that bleeding on probing was less extensive in smokers (P< 0.001). Cell counts and elastase content of crevicular PMNLs showed no differences between groups. Lower concentrations of elastase were found in GCF supernatants from smokers than non-smokers. This difference was observed for functional elastase (mean [s.d.] = 30.21 [17.60] against 73.77 [75.26] ng μI-1, P <0.05) and elastase complexed with αl-antitrypsin (8.97 [6.54] ng μl-1 against 25.71 [22.07] ng μI-1, P < 0.001).
CONCLUSIONS: Smokers have lower elastase concentrations in GCF than non-smokers. Further investigation is required to elucidate the underlying cause and its relationship with periodontal disease.  相似文献   
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