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61.
Cytomegalovirus is the single most important pathogen in clinical transplantation. Although much progress has been made in our understanding of the molecular biology and epidemiology of CMV infection and in our ability to diagnosis and treat CMV disease, it remains a major cause of morbidity but is no longer a major cause of mortality after liver transplantation. Risk factors for CMV disease after liver transplantation include donor and recipient serologic status, the use of antilymphocyte therapy, and retransplantation. CMV disease occurs early after transplantation, and the most frequent site of disease is the hepatic allograft. We have treated 79 patients with intravenous ganciclovir, with ultimate control of disease achieved in 69 patients (87.3%). Preliminary results using intravenous immunoglobulin and oral acyclovir for CMV prophylaxis in high-risk patients have been encouraging. In addition to producing clinical syndromes, CMV may have direct immunologic effects and is a marker of the net state of immunosuppression.  相似文献   
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The feasibility of in vitro interleukin 2 (IL-2) activation and expansion of mononuclear cells (MNCs) derived from adult patients with acute myelogenous leukemia (ANLL) was studied. Patients' natural killer (NK) and lymphokine-activated killer (LAK) cell activity was compared with that of normal donors in terms of: (a) cytolytic activity (four- hour 51Cr release assay) against an NK-sensitive target (K562), NK- resistant targets (Raji/Daudi), and fresh/cryopreserved autologous and allogeneic leukemic blasts; (b) proliferation and expansion in culture with 1,000 U/mL recombinant IL 2 (rIL 2); and (c) the cell surface phenotype of the cultured cells. In 21 of 24 patients with active disease (AP) MNCs derived from the peripheral blood (PBL) or bone marrow (BM) could be cultured and expanded in the presence of rIL 2. These cultures initially contained between 30% and 50% blasts, and during 2 to 4 weeks of culture destruction of blasts and enrichment of up to 60% in cells with the morphology of large granular lymphocytes (LGLs) was observed. Expansion in culture varied between two- and 100- fold. MNCs from all patients in remission (RP) could be activated by rIL 2 and expanded up to 30-fold after 1 to 3 weeks in culture. NK activity of fresh PBLs from AP was significantly lower than in normal controls, whereas NK activity of RP was within the normal range. High levels of postactivation NK and LAK activity on K562/Raji/Daudi and on fresh/cryopreserved leukemic blasts was generated in approximately 50% of cases of AP and in most RP. Cell surface phenotype studies showed that cultured cells derived from ANLL patients were significantly enriched (up to 40%) in NKH-1 (Leu 19) positive cells, with RP LAK cells also expressing a high proportion of CD16 positive cells (up to 40%). This study has shown that it is feasible to activate and significantly expand killer cells derived from active disease and remission ANLL patients during 1 to 3 weeks culture with IL 2 with good maintenance of cytolytic activity. Both initial NK activity and LAK generation was optimal in remission patients. Based on data from this study, a clinical protocol has been developed for treatment of early relapse ANLL patients with LAK cells cultured for 1 to 3 weeks and systemic IL 2.  相似文献   
64.
We report the successful long-term engraftment of normal male donor bone marrow (BM) transfused into noncytoablated female mice, challenging the assumption that "niches" need to be created for marrow to engraft. We have used chromosomal banding and Southern blot analysis to identify transplanted male marrow cells, and shown the long-term stability of the chimeric marrows. Balb/C, BDF1, or CBA-J female hosts (no irradiation) received for 5 consecutive days 40 x 10(6) male cells (per day) of the same strain, and repopulation patterns were observed. Parallel studies were performed using tibia/femur equivalents of normal marrow or marrow from Balb/C mice pretreated 6 days previously with 150 mg/kg 5-fluorouracil (5-FU). Chromosome banding techniques showed that 5% to 46% of marrow cells were male 3 to 9 months posttransplant with normal donor marrow. Southern blot analysis, using the pY2 probe, showed continued engraftment at 21 to 25 months posttransplant, ranging from 15% to 42% male engrafted cells in marrow. Normal donor male marrow engrafted significantly better than 5-FU-pretreated male marrow as shown 1 to 12 months posttransplant in non-cytoablated female recipients. Percentages of male engrafted cells in BM ranged from 23% to 78% for recipients of normal donor marrow and from 0.1% to 39% for recipients of 5-FU marrow. Mean engraftment for 6 mice receiving normal marrow was 38%, whereas that for 6 mice receiving post-5-FU marrow was 8%, as assayed 1 to 3 months posttransplant. At 10 to 12 months, mean engraftment for the normal donor group was 46%, compared with 16% for the 5-FU group. The patterns of engraftment with normal and 5-FU marrow were similar for spleen and thymus. These results show that long-term chimerism can be established after transplantation of normal donor marrow to normal nonirradiated host mice and indicate that marrow spaces do not have to be created for successful engraftment. They suggest that transplanted marrow competes equally with host marrow for marrow space. Finally, these data show that post-5-FU Balb/C male marrow is markedly inferior in the repopulation of Balb/C female host marrow, spleen, and thymus, and suggest that this population of cells may not be the ideal population for gene transfer studies.  相似文献   
65.
A phase I clinical trial was initiated to treat patients with stage IV B-derived chronic lymphocytic leukemia (CLL) with the IgG2a murine monoclonal antibody T101. This antibody binds to a 65,000-mol wt (T65) antigen found on normal T lymphocytes, malignant T lymphocytes, and B- derived CLL cells. All of the patients had a histologically confirmed diagnosis of advanced B-derived CLL and were refractory to standard therapy, and more than 50% of their leukemia cells reacted with the T101 antibody in vitro. The patients received T101 antibody two times per week, over two to 50 hours by intravenous administration in 100 mL of normal saline containing 5% human albumin. Twelve patients were treated with a fixed dosage of 1, 10, 50, or 100 mg, and one patient was treated with 140 mg of antibody. It was demonstrated that patients given two-hour infusions of 50 mg developed pulmonary toxicity, with shortness of breath and chest tightness. This toxicity was eliminated when infusions of 50 or 100 mg of T101 were prolonged to 50 hours. All dose levels caused a rapid but transient decrease in circulating leukemia cell counts. In vivo binding to circulating and bone marrow leukemia cells was demonstrated at all dose levels with increased binding at higher dosages. Antimurine antibody responses were not demonstrated in any patients at any time during treatment. Circulating free murine antibody was demonstrated in the serum of only the two patients treated with 100 mg of antibody as a 50-hour infusion and the patient treated with 140 mg of antibody over 30 hours. Antigenic modulation was demonstrated in patients treated at all dose levels but was particularly apparent in patients treated with prolonged infusions of 50 and 100 mg of antibody. We were also able to demonstrate antigenic modulation in lymph node cells, which strongly suggests in vivo labeling of these cells. Overall, T101 antibody alone appears to have a very limited therapeutic value for patients with CLL. The observations of in vivo labeling of tumor cells, antigenic modulation, antibody pharmacokinetics, toxicity, and antimurine antibody formation may be used in the future for more effective therapy when drugs or toxins are conjugated to the antibody.  相似文献   
66.
The Randomized Endo‐vein Graft Prospective (REGROUP) trial ( ClinicalTrials.gov  NCT01850082) is a randomized, intent‐to‐treat, 2‐arm, parallel‐design, multicenter study funded by the Cooperative Studies Program (CSP No. 588) of the US Department of Veterans Affairs. Cardiac surgeons at 16 Veterans Affairs (VA) medical centers with technical expertise in performing both endoscopic vein harvesting (EVH) and open vein harvesting (OVH) were recruited as the REGROUP surgeon participants. Subjects requiring elective or urgent coronary artery bypass grafting using cardiopulmonary bypass with use of ≥1 saphenous vein graft will be screened for enrollment using pre‐established inclusion/exclusion criteria. Enrolled subjects (planned N = 1150) will be randomized to 1 of the 2 arms (EVH or OVH) after an experienced vein harvester has been assigned. The primary outcomes measure is the rate of major adverse cardiac events (MACE), including death, myocardial infarction, or revascularization. Subject assessments will be performed at multiple times, including at baseline, intraoperatively, postoperatively, and at discharge (or 30 days after surgery, if still hospitalized). Assessment of leg‐wound complications will be completed at 6 weeks after surgery. Telephone follow‐ups will occur at 3‐month intervals after surgery until the participating sites are decommissioned after the trial's completion (approximately 4.5 years after the full study startup). To assess long‐term outcomes, centralized follow‐up of MACE for 2 additional years will be centrally performed using VA and non‐VA clinical and administrative databases. The primary MACE outcome will be compared between the 2 arms, EVH and OVH, at the end of the trial duration.  相似文献   
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68.
Background: The incidence of obesity is rising, and an increasing number of obese patients are admitted to surgical intensive care units (SICUs). However, it is not clear whether obesity is an independent risk factor for increased morbidity and mortality in SICU patients. We examined the effect of obesity on morbidity and mortality in patients admitted to the SICU in this study. Method: We reviewed prospectively acquired SICU data in normal and obese patients with an SICU length of stay >24 hours. Comparability of the groups was assessed using a χ2 test or Fisher exact test, as appropriate, for categorical variables and analysis of variance (ANOVA) or the Kruskal‐Wallis test, as appropriate, for continuous variables. Results: Of the 1792 consecutive patients evaluated, 711 had a normal body mass index (BMI), and 993 were either preobese or obese. There was no statistically significant difference across the 5 BMI groups with respect to any of the 3 comorbidity indices (Acute Physiology and Chronic Health Evaluation III [APACHE III], Simplified Acute Physiology Score, or Multiple Organ Dysfunction Score). There was no statistically significant difference in the intensive care unit (ICU) length of stay and hospital length of stay or time‐to‐ICU mortality (log‐rank test P = .054) among the 5 BMI groups. A Cox regression analysis and backward elimination algorithm selected APACHE III to be the most important explanatory variable for survival time. Conclusion: Obesity does not affect the mortality of patients admitted to the SICU. We conclude that obesity cannot be used as an independent predictive mortality outcome variable in patients admitted to the SICU.  相似文献   
69.
ObjectiveTo investigate the potentials of the root bark of Annona (A.) senegalensis in the control of seizure and related hypnotic and motor incoordination effects in mice using experimental models.MethodsThe methanol extract (ME) of the root bark of A. senegalensis was studied in mice using pentylenetetrazole (PTZ) induced convulsions, phenobarbitone induced sleeping time and motor coordination test on rota-rod performance. Acute toxicity and lethality (LD50) test as well as phytochemical analysis were also carried out.ResultsThe extract (200, 400, 800 mg/kg) exhibited a non-dose dependent significant (P <0.05) delay in the onset of both tonic and clonic phases of seizure induced by PTZ (60 mg/kg, s.c.) as well as offered a 100% protection (200 mg/kg) in mice from PTZ induced seizures. The extract significantly (P <0.05) decreased the latency and increased the duration of phenobarbitone induced sleeping time. At 200 mg/kg, the extract exhibited a significant (P <0.05) motor incoordination. The acute toxicity test revealed an oral LD50 of 1 296 mg/kg, while the phytochemical studies showed the presence of alkaloids, resins, glycosides, carbohydrate, reducing sugar, flavonoids, terpenoids, saponins and tannins.ConclusionThe extract of A. senegalensis possessed anticonvulsant activity with pronounced hypnotic and muscle relaxant effects.  相似文献   
70.
We have read the recent comprehensive review by Cruz et al.[1] regarding the targeting of receptor tyrosine kinases andtheir therapeutic perspectives in head and neck squamous cellcarcinomas (HNSCC). The major focus of this report was epidermalgrowth factor receptor (EGFR) biology and targeting. However,we feel  相似文献   
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