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Solid organ transplant (SOT) recipients may be at higher risk for poor outcomes with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Convalescent plasma is an investigational therapy that may benefit immunosuppressed patients by providing passive immunity. Convalescent plasma was administered to hospitalized patients with coronavirus disease-2019 (COVID-19) at an academic transplant center in New York City. Eligible patients were hospitalized and required to have positive nasopharyngeal polymerase chain reaction (PCR) diagnosis of SARS-CoV-2 infection, be at least 18 years old, and have either dyspnea, blood oxygen saturation ≤ 93% on ambient air, respiratory frequency ≥ 30 breaths/min, partial pressure of arterial oxygen to fraction of inspired oxygen ratio < 300, or lung infiltrates > 50%. Thirteen SOT recipients received convalescent plasma from April 9, 2020, to May 17, 2020. The median time from symptom onset to plasma infusion was 8 days. Eight of 13 patients (62%) had de-escalating oxygenation support by day 7 post-convalescent plasma. Nine (69%) patients were discharged, 1 (7%) patients remain hospitalized, and 3 (23%) patients died. This series supports the need for additional studies on convalescent plasma use in SOT recipients with COVID-19 to better determine efficacy and identify patients who are likely to benefit.  相似文献   
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Background

Chronic rejection is a major cause of graft loss in kidney transplant recipients. Nonadherence to drug therapy is a well-recognized cause of chronic rejection leading to long-term graft dysfunction and failure for transplant recipients. Immunosuppressive medications with short half-lives that require frequent dosing, such as tacrolimus, complicate transplant regimens and may increase noncompliance. Regimens could be simplified using drugs with long half-lives requiring once-daily administration, such as sirolimus. The impact of missing doses of single agents has not been studied extensively. Erratic compliance or temporary discontinuation of immunosuppressive drugs may have significant implications for chronic rejection.

Methods

Our study evaluated the impact of single drug withdrawal of commonly used immunosuppressive agents (sirolimus and tacrolimus) on lymphocyte responses. We analyzed lymphocyte proliferation, cytokine secretion, and adenosine triphosphate generation using a crossover study design with normal healthy patients. Lymphocyte proliferation was assessed using 5-bromo-2-deoxyuridine incorporation, and T cell function was analyzed by examining adenosine triphosphate generation.

Results

Our results indicate that sirolimus exerts prolonged suppression of lymphocyte proliferation and decreased interleukin 17A that lasts up to 48 h after drug withdrawal. In comparison, tacrolimus did not have a similar effect on lymphocyte proliferation or interleukin 17A secretion.

Conclusion

Future analysis of sirolimus in diverse transplantation populations merits investigation.  相似文献   
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Background

While anemia occurs in 80 % to 90 % of patients with celiac disease (CD), it may be the sole manifestation of CD. The prevalence of CD in Indian patients with nutritional anemia is not known.

Patients and Methods

Adolescent and adult patients presenting with nutritional anemia were prospectively screened for CD using IgA anti-tissue transglutaminase antibody (anti-tTG Ab) followed, if positive, by upper gastrointestinal endoscopy and duodenal biopsy.

Results

Ninety-six patients [mean?±?SD age 32.1?±?13.1 years and median duration of anemia 11 months (range 1 to 144 months)] were screened. Of these patients, 80 had iron deficiency anemia, 11 had megaloblastic anemia, and 5 had dimorphic anemia. Seventy-three patients were on hematinics and 36.4 % had received blood transfusions. Nineteen had a history of chronic diarrhea and the mean?±?SD duration of diarrhea in them was 9.7?±?35.8 months. IgA anti-tTG Ab was positive in 13 patients, of whom 12 agreed to undergo duodenal biopsy. Ten patients had villous atrophy (Marsh grade 3a in three, 3b in one, and 3c in six) and two did not. Thus, 10 patients with nutritional anemia (iron deficiency 9, vitamin B12 deficiency 1) were diagnosed to have CD. On multivariate logistic regression, age, duration of symptoms, and presence of diarrhea were found to be the predictors of CD. All the patients with CD were put on gluten-free diet and with iron and vitamin supplementations and showed a significant improvement in hemoglobin concentration.

Conclusions

CD screening should be included in the work up of otherwise unexplained nutritional anemia.  相似文献   
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Prosthesis refers to artificial replacement of an absent part of the human body. These prostheses help in psychological support of the patients and enhance their social acceptance. Complete or partial finger amputations are some of most frequently encountered forms of partial hand loss. Micro vascular reconstruction is the first choice of rehabilitation but when it is contraindicated, unavailable, unsuccessful or unaffordable, the prosthetic rehabilitation is an alternative for improving the psychological status of an individual. Most of these artificial prostheses make use of silicone. The present paper tries to combine aesthetics with function. The authors have created functionally active finger prosthesis with the help of electromechanical controls. The prosthesis is battery-powered, light-weight, and allows the user to regain complete control of flexion and extension movements of an artificial finger.

  相似文献   
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BACKGROUND: Stent-based delivery of sirolimus (SRL) has shown reduction in neointimal hyperplasia and restenosis. The purpose of this study was to evaluate the chronic vascular response and the expression of cell cycle regulators after SRL-eluting stent implantation in a porcine coronary model. METHODS: Forty-nine pigs underwent placement of 109 oversized stents (control, n=54, SRL (140 microg/cm(2)), n=55) in the coronary arteries with histologic analysis and Western blot (PCNA, p27(kip1), CD45, MCP-1, IL-2, IL-6, TNF-beta) at 3, 30, 90 or 180 days. RESULTS: At 3 days, the mean thrombus area was similar for control (0.38+/-0.19 mm(2)) and SRL (0.29+/-0.09 mm(2)) stents. After 30 days, the mean neointimal area was significantly less for the SRL (1.40+/-0.35 mm(2)) versus the control stents (2.94+/-1.28 mm(2), p<0.001). At 90 and 180 days, the mean neointimal area was similar for the SRL (3.03+/-0.92 and 3.34+/-0.99 mm(2)) as compared with control stents (3.45+/-1.09 and 3.65+/-1.23 mm(2)). Western blot analysis demonstrated an increased expression of p27(kip1) in the vessel wall at 90 days for the SRL versus control stents (p=0.05) but with increased levels of PCNA in the SRL as compared with control stents (p=0.003). CONCLUSION: SRL-eluting stents favorably modulate neointimal formation for 30 days in the porcine coronary model. Long-term inhibition of neointimal hyperplasia is not sustained presumably due to delayed cellular proliferation despite increased levels of the cyclin-dependent kinase p27(kip1) in the vessel wall.  相似文献   
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