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Now is an exciting era of development in immunotherapy checkpoint inhibitors and their effect on the treatment of NPC. While the general prognosis of R/M disease is poor, immunotherapy offers some promise in a malignancy associated with EBV and characterized by a peritumoural immune infiltrate. Our study aims to review past and on-going clinical trials of monoclonal antibody therapies against the checkpoint inhibitors (e.g. PD1 and CTLA-4), in R/M NPC. All randomized and nonrandomized controlled trials involving immune checkpoint inhibitor interventions for treatment of NPC were included in the study. We utilized a validated “risk of bias” tool to assess study quality. Four separate Phase I–II trials report the potential of PD1 inhibitor treatment for patients with NPC. Within the observed groups, camrelizumab combined with chemotherapy achieved an objective response in 91% of patients as first-line treatment for metastatic NPC (PFS 68% at 1-year) but this was associated with a high rate of grade >3 adverse events (87%; CTCAE version 4.03). The remaining three studies focused on recurrent NPC disease in patients who had received at least one line of prior chemotherapy. Within this group, camrelizumab monotherapy achieved an objective response in 34% of patients (PFS 27% at 1-year; range across all three studies 20.5–34%). No NPC trial has yet reported on specific outcomes for non-PD1 checkpoint inhibitors but 11 on-going studies include alternative targets (e.g. PD-L1/CTLA-4) as combination or monotherapy treatments. In considering checkpoint immunotherapies for NPC, initial results show promise for anti-PD1 interventions. Further phase I–III trials are in progress to clarify clinical outcomes, fully determine safety profiles, and optimize drug combinations and administration schedules.  相似文献   
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Antibody-mediated rejection is a major complication in renal transplantation. The pathologic manifestations of acute antibody-mediated rejection that has progressed to functional impairment of a renal transplant have been defined in clinical biopsy specimens. However, the initial stages of the process are difficult to resolve with the unavoidable variables of clinical studies. We devised a model of renal transplantation to elucidate the initial stages of humoral rejection. Kidneys were orthotopically allografted to immunodeficient mice. After perioperative inflammation subsided, donor-specific alloantibodies were passively transferred to the recipient. Within 1 hour after a single transfer of antibodies, C4d was deposited diffusely on capillaries, and von Willebrand factor released from endothelial cells coated intravascular platelet aggregates. Platelet-transported inflammatory mediators platelet factor 4 and serotonin accumulated in the graft at 100- to 1000-fold higher concentrations compared with other platelet-transported chemokines. Activated platelets that expressed P-selectin attached to vascular endothelium and macrophages. These intragraft inflammatory changes were accompanied by evidence of acute endothelial injury. Repeated transfers of alloantibodies over 1 week sustained high levels of platelet factor 4 and serotonin. Platelet depletion decreased platelet mediators and altered the accumulation of macrophages. These data indicate that platelets augment early inflammation in response to donor-specific antibodies and that platelet-derived mediators may be markers of evolving alloantibody responses.  相似文献   
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Fraudulent business practices, such as those leading to the Enron scandal and the conviction of Bernard Madoff, evoke a strong sense of public outrage. But fraudulent or dishonest actions are not exclusive to the realm of big corporations or to evil individuals without consciences. Dishonest actions are all too prevalent in everyone’s daily lives, because people are constantly encountering situations in which they can gain advantages by cutting corners. Whether it’s adding a few dollars in value to the stolen items reported on an insurance claim form or dropping outlier data points from a figure to make a paper sound more interesting, dishonesty is part of the human condition. Here, we explore how people rationalize dishonesty, the implications for scientific research, and what can be done to foster a culture of research integrity.  相似文献   
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Triple-negative breast cancer (TNBCs) is a very aggressive and lethal form of breast cancer with no effective targeted therapy. Neoadjuvant chemotherapies and radiotherapy remains a mainstay of treatment with only 25–30% of TNBC patients responding. Thus, there is an unmet clinical need to develop novel therapeutic strategies for TNBCs. TNBC cells have increased intracellular oxidative stress and suppressed glutathione, a major antioxidant system, but still, are protected against higher oxidative stress. We screened a panel of antioxidant genes using the TCGA and METABRIC databases and found that expression of the thioredoxin pathway genes is significantly upregulated in TNBC patients compared to non-TNBC patients and is correlated with adverse survival outcomes. Treatment with auranofin (AF), an FDA-approved thioredoxin reductase inhibitor caused specific cell death and impaired the growth of TNBC cells grown as spheroids. Furthermore, AF treatment exerted a significant in vivo antitumor activity in multiple TNBC models including the syngeneic 4T1.2 model, MDA-MB-231 xenograft and patient-derived tumor xenograft by inhibiting thioredoxin redox activity. We, for the first time, showed that AF increased CD8+Ve T-cell tumor infiltration in vivo and upregulated immune checkpoint PD-L1 expression in an ERK1/2-MYC-dependent manner. Moreover, combination of AF with anti-PD-L1 antibody synergistically impaired the growth of 4T1.2 primary tumors. Our data provide a novel therapeutic strategy using AF in combination with anti-PD-L1 antibody that warrants further clinical investigation for TNBC patients.  相似文献   
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BACKGROUND: Nocardia is responsible for infection in both normal and immunocompromised hosts. Organ transplant recipients are increasingly recognized as a sub-group of immunocompromised patients in whom nocardia is an important pathogen. The frequency of nocardia in organ transplant recipients varies between 0.7% and 3%. Nocardia infection has largely been reported in heart, kidney and liver transplant recipients. Presentations of nocardia in lung transplant recipients have been restricted primarily to case reports. The present study reviews the clinical and epidemiologic characteristics of nocardia infection in lung transplant recipients at our institution. METHODS: A retrospective cohort study of 473 lung transplant recipients from January 1991 to November 2000 was done at a university hospital. Patient demographics, immunosuppressive regimen at the time of isolation of nocardia species, use of trimethoprim-sulfamethoxazole for Pneumocystis carinii prophylaxis, rejection episodes in the preceding 6 months, concurrent pathogens, site of infection, radiologic findings and treatment and outcome were recorded. RESULTS: Nocardia infection was found in 2.1% (10 of 473) of our lung transplant recipients. Median time of onset was 34.1 months after transplantation. Nocardia species included N farcinica in 30% (3 of 10), N nova in 30% (3 of 10), N asteroides complex in 30% (3 of 10) and N brasiliensis in 10% (1 of 10) of patients. Post-transplant diabetes was present in 50% (5 of 10) of patients. The primary indication for lung transplantation was emphysema in 40% (4 of 10). Native lung involvement was noted in 75% (3 of 4) of patients with single lung transplant. Breakthrough nocardia infection were noted in 6 patients who were receiving trimethoprim-sulfamethoxazole prophylaxis for P carinii pneumonia; all breakthrough isolates remained susceptible to trimethoprim-sulfamethoxazole. Overall mortality was 40% (4 of 10). All patients (3 of 3) with infection due to N farcinica, except 1 (1 of 7) with infection due to other nocardia species, died. Seventy-five percent (3 of 4) of deaths were attributable to nocardia infection. CONCLUSIONS: Nocardia infection tended to involve the native lung in single lung transplant recipients. Trimethoprim-sulfamethoxazole for P carinii prophylaxis at the doses given was not protective against nocardiosis in these patients. Infection with N farcinica was associated with poor outcome. Thus, species identification and extended courses of antibiotics based on antimicrobial susceptibility testing are important in management of these patients.  相似文献   
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