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1.
BackgroundDetails of perioperative outcomes and survival after gastric cancer surgery in prior transplant recipients have received minimal research attention.MethodsWe performed an observational cohort study using the database of 20,147 gastric cancer patients who underwent gastrectomy at a single gastric cancer center in Korea. Forty-one solid organ recipients [kidney (n = 35), liver (n = 5), or heart (n = 1)] were matched with 205 controls using propensity score matching.ResultsOperation time, blood loss, and postoperative pain were similar between groups. Short-term complication rates were similar between transplantation and control groups (22.0% vs. 20.1%, P = 0.777). Transplantation group patients with stage 1 gastric cancer experienced no recurrence, while those with stage 2/3 cancer had significantly higher recurrence risk compared to the controls (P = 0.049). For patients with stage 1 cancer, the transplantation group had a significantly higher rate of non-gastric cancer-related deaths compared to the controls (19.2% vs. 1.4%, P = 0.001). For those with stage 2/3 cancer, significantly lower proportion of the transplantation group received adjuvant chemotherapy compared to the control group (26.7% vs. 80.3%, P < 0.001). The transplantation group had a higher (albeit not statistically significant) rate of gastric cancer-related deaths compared to the controls (40.0% vs. 18.0%, P = 0.087).ConclusionTransplant recipients and non-transplant recipients exhibited similar perioperative and short-term outcomes after gastric cancer surgery. From long-term outcome analyses, we suggest active surveillance for non-gastric cancer-related deaths in patients with early gastric cancer, as well as strict oncologic care in patients with advanced cancer, as effective strategies for transplant recipients.  相似文献   
2.
目的 揭示大脑中动脉闭塞(MCAO)后丘脑钙调磷酸酶(CaN)的时空变化规律,探讨CaN的作用机制。方法 制备大鼠大脑中动脉永久性闭塞模型,分别测定缺血后不同时间点病灶侧丘脑CaN的活性和含量。结果 缺血后24h始丘脑CaN的含量下降且不恢复;CaN的活性在缺血后2h和4h减弱,6h始恢复至正常水平。可见,CaN的活性与含量分离。结论 大脑中动脉闭塞后丘脑CaN活性独特的时间变化规律显示其参与介导继发性丘脑损伤,可能具有毒性作用。  相似文献   
3.
Calcineurin inhibitor (CNI) withdrawal has been used as a strategy to improve renal allograft function, however, it also carries risk of acute rejection. We conducted a systematic review of randomized trials that involved CNI withdrawal from a sirolimus-based immunosuppressive regimen. The search strategy yielded six trials (n = 1047 patients) reported in eight publications. CNI withdrawal from sirolimus-based therapy, was associated with an increased risk of acute rejection (risk difference, 6%; 95% CI 2-10%, p = 0.002) but a higher creatinine clearance (mean difference, 7.49 mL/min; 95% CI 5.08-9.89 mL/min, p < 0.00001) at 1 year compared to continued CNI and sirolimus therapy. Graft loss (relative risk, 0.87; 95% CI 0.46-1.64, p = 0.66) and death (relative risk, 0.88; CI 0.40-1.96, p = 0.76) were similar in both groups at 1 year. Hypertension was significantly reduced in the CNI withdrawal group (relative risk, 0.56; 95% CI 0.40-0.78, p = 0.0006). CNI withdrawal from sirolimus-based therapy is associated with an increased risk of acute rejection in the short term with a significant improvement in renal function and a reduction in hypertension. Longer follow-up is needed to determine if these changes will result in a significant improvement in patient and graft survival.  相似文献   
4.
Tailoring immunosuppressive therapy.   总被引:1,自引:1,他引:0  
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5.
建立慢性酒精中毒致大鼠学习记忆障碍模型,通过免疫组织化学法检测大鼠大脑皮层、海马和丘脑内钙神经素(calci-neurin,CaN)和Tau蛋白Thr231位点(Tau-Thr231)的分布与表达,探讨其在慢性酒精中毒致大鼠学习记忆障碍发病机理中的作用。成年雄性SD大鼠随机平均分为对照组和染毒组。对照组大鼠以生理盐水灌胃,染毒组则以55%酒精灌胃。运用Morris水迷宫检测大鼠学习记忆功能损伤情况,免疫组织化学法检测大脑皮层、海马和丘脑CaN和Tau-Thr231分布及表达,并测定CaN和Tau-Thr231免疫阳性细胞数。慢性酒精中毒后大鼠学习记忆功能有不同程度损伤。染毒组大脑皮层和海马CaN表达较对照组上调(P<0.05);染毒组大脑皮层和海马Tau-Thr231表达较对照组下调(P<0.05)。丘脑未见CaN表达,对照组丘脑可见Tau-Thr231免疫阳性细胞分布,染毒组Tau-Thr231免疫阳性细胞数量逐渐减少,提示慢性酒精中毒致大鼠学习记忆功能损伤可能与大鼠大脑皮层、海马和丘脑内CaN和Tau-Thr231的表达变化相关。  相似文献   
6.
BackgroundSurvivors of childhood cancer may be at increased risk for treatment-related kidney dysfunction. Although associations with acute kidney toxicity are well described, evidence informing late kidney sequelae is less robust.MethodsTo define the prevalence of and risk factors for impaired kidney function among adult survivors of childhood cancer who had been diagnosed ≥10 years earlier, we evaluated kidney function (eGFR and proteinuria). We abstracted information from medical records about exposure to chemotherapeutic agents, surgery, and radiation treatment and evaluated the latter as the percentage of the total kidney volume treated with ≥5 Gy (V5), ≥10 Gy (V10), ≥15 Gy (V15), and ≥20 Gy (V20). We also used multivariable logistic regression models to assess demographic and clinical factors associated with impaired kidney function and Elastic Net to perform model selection for outcomes of kidney function.ResultsOf the 2753 survivors, 51.3% were men, and 82.5% were non-Hispanic White. Median age at diagnosis was 7.3 years (interquartile range [IQR], 3.3–13.2), and mean age was 31.4 years (IQR, 25.8–37.8) at evaluation. Time from diagnosis was 23.2 years (IQR, 17.6–29.7). Approximately 2.1% had stages 3–5 CKD. Older age at evaluation; grade ≥2 hypertension; increasing cumulative dose of ifosfamide, cisplatin, or carboplatin; treatment ever with a calcineurin inhibitor; and volume of kidney irradiated to ≥5 or ≥10 Gy increased the odds for stages 3–5 CKD. Nephrectomy was significantly associated with stages 3–5 CKD in models for V15 or V20.ConclusionsWe found that 2.1% of our cohort of childhood cancer survivors had stages 3–5 CKD. These data may inform screening guidelines and new protocol development.  相似文献   
7.
Group I and Epstein–Barr virus-negative Burkitt's lymphomacell lines and the B104 lymphoma cell line which expresses aphenotype of immature B cells undergo apoptosis after cross-linkingof their surface Ig receptors or after exposure to a calciumionophore. We show here that tumor necrosis factor (TNF)- protectsthese B cell lines against Ca2+-dependent apoptosis. Protectionwas associated with up-regulatlon of bcl-2 mRNA and proteinexpression. The increase of Bcl-2 expression induced by TNF-was inhibited by chelerythrine, a specific inhibitor of proteinkinase C (PKC), suggesting that Bcl-2 expression was dependenton PKC activation. Furthermore, we show that phorbol estersand cyclosporin A (CsA), which prevent Ca2+-dependent apoptosis,up-regulated Bcl-2 expression. The effect of CsA on Bcl-2 expressionis controlled by calcineurin since we have shown that FK506but not rapamycin had the same effect on Bcl-2 expression, whereasokadaic acid, an inhibitor of phosphatases 1, 2A and 2C, wasineffective. These data provide direct evidence that TNF- preventsCa2+-dependent apoptosis by a Bcl-2-dependent mechanism mediatedby PKC.  相似文献   
8.
目的研究转录因子NFATc及NF-κB在钙神经素介导的脑缺血再灌注损伤中的作用。方法Western blotting和EMSA分子生物学技术。结果与对照组相比较,CsA明显减低I/R组Fas配体和NFATc的蛋白表达;对照组、I/R组和CsA处理组I-κB-α蛋白表达无显著区别;未观察到对照组、I/R组和CsA处理组有phospho-I-κB-α蛋白表达;与对照组相比较,CsA明显减低I/R组Fas配体启动子远端和Fas配体启动子近端NFAT结合位点的NFAT-DNA结合活性(P<0.01)。结论转录因子NFATc参与钙神经素介导的脑缺血再灌注损伤,促进CD95配体分子的转录表达;NF-κB可能未参与钙神经素介导的脑缺血再灌注损伤的作用机制。  相似文献   
9.
Calcineurin inhibitors (CNIs) are potent immunosuppressants that reversibly inhibit T-cell proliferation and prevent the release of pro-inflammatory cytokines by blocking the activity of calcineurin, a ubiquitous enzyme that is found in cell cytoplasm. CNIs can be highly effective in immune-mediated ophthalmic diseases such as uveitis, dry eye syndrome and inflammatory blepharitis, as well as for the prevention of rejection in corneal transplants. ISA-247/LX-211 is a novel CNI that is in Phase III clinical development for the treatment of various forms of non-infectious uveitis. ISA-247/LX-211 is a rationally designed analog of ciclosporin A that exhibits more predictable pharmacokinetic and pharmacodynamic properties and a 4-fold greater calcineurin inhibition than its parent compound, ciclosporin A. ISA-247/LX-211 has been observed to be effective, well-tolerated, and safe in early clinical trials, exhibiting a much wider therapeutic window compared with classic CNIs, such as ciclosporin A and tacrolimus. An alternative approach to widening the therapeutic window for the therapy of ophthalmic disorders lies in local delivery of CNIs through polymeric implants that release the drug over long periods of time. The silicone matrix episcleral implant LX-201 is in Phase III development at present for the prevention of rejection in high-risk cornea transplantation.  相似文献   
10.
Since its introduction to the antirejection armamentarium in 1994, tacrolimus has become the workhorse of transplant professionals for avoidance of solid organ transplant rejection. Not only does tacrolimus have potent immunosuppressive qualities that prevent rejection, but dosing is straight forward and it is generally well tolerated. However, in the long term, conditions such as calcineurin inhibitor nephrotoxicity can become a problem. A discussion of the compound, the pharmacokinetics, history, and current approved uses for tacrolimus is described. Indeed, tacrolimus is the most important drug for preventing transplant rejection. However, the increased appreciation for significant side effects, particularly in the long term, has led to building interest in new agents with different mechanisms of action and different metabolism.  相似文献   
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