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31.
Henrietta Nittby Peter Ericsson Karolina F?rnvik Susanne Str?mblad Linda Jansson Zhongtian Xue Gunnar Skagerberg Bengt Widegren Hans-Olov Sj?gren Leif G. Salford 《PloS one》2013,8(8)
Background
Coping with the immune rejection of allotransplants or autologous cells in patients with an active sensitization towards their autoantigens and autoimmunity presently necessitates life-long immune suppressive therapy acting on the immune system as a whole, which makes the patients vulnerable to infections and increases their risk of developing cancer. New technologies to induce antigen selective long-lasting immunosuppression or immune tolerance are therefore much needed.Methodology/Principal Findings
The DNA demethylating agent Zebularine, previously demonstrated to induce expression of the genes for the immunosuppressive enzymes indolamine-2,3-deoxygenase-1 (IDO1) and kynureninase of the kynurenine pathway, is tested for capacity to suppress rejection of allotransplants. Allogeneic pancreatic islets from Lewis rats were transplanted under the kidney capsule of Fischer rats previously made diabetic by a streptozotocin injection (40 mg/kg). One group was treated with Zebularine (225 mg/kg) daily for 14 days from day 6 or 8 after transplantation, and a control group received no further treatment. Survival of the transplants was monitored by blood sugar measurements. Rats, normoglycemic for 90 days after allografting, were subjected to transplant removal by nephrectomy to confirm whether normoglycemia was indeed due to a surviving insulin producing transplant, or alternatively was a result of recovery of pancreatic insulin production in some toxin-treated rats. Of 9 Zebularine treated rats, 4 were still normoglycemic after 90 days and became hyperglycemic after nephrectomy. The mean length of normoglycemia in the Zebularine group was 67±8 days as compared to 14±3 days in 9 controls. Seven rats (2 controls and 5 Zebularine treated) were normoglycemic at 90 days due to pancreatic recovery as demonstrated by failure of nephrectomy to induce hyperglycemia.Conclusions/Significance
Zebularine treatment in vivo induces a long-lasting suppression of the immune destruction of allogeneic pancreatic islets resulting in protection of allograft function for more than 10 weeks after end of treatment. 相似文献32.
33.
Avid Mohammadi Sareh Bagherichimeh Yoojin Choi Azadeh Fazel Elizabeth Tevlin Sanja Huibner Zhongtian Shao David Zuanazzi Jessica L. Prodger Sara V. Good Wangari Tharao Rupert Kaul 《PLoS pathogens》2022,18(1)
The penis is the primary site of HIV acquisition in heterosexual men. Elevated penile inflammatory cytokines increase sexual acquisition risk, and topically applied cytokines enhance foreskin HIV susceptibility in an explant model. However, the impact of penile-vaginal sex on these immune parameters is undefined. Heterosexual couples were recruited to the Sex, Couples and Science (SECS) Study, with the collection of penile swabs, semen, cervico-vaginal secretions, and blood after a period of abstinence, and repeated sampling up to 72 hours after either condomless (n = 30) or condom-protected (n = 8) penile-vaginal sex. Soluble immune parameters were quantified by multiplex immunoassay. Co-primary immune endpoints were penile levels of IL-8 and MIG, cytokines previously linked to penile HIV acquisition. One hour after sex there were dramatic increases in penile IL-8 and MIG levels, regardless of condom use, with a gradual return to baseline by 72 hours; similar patterns were observed for other chemoattractant chemokines. Penile cytokine changes were similar in circumcised and uncircumcised men, and repeated measures ANOVA and ANCOVA models demonstrated that the degree of change after condomless sex was explained by cytokine levels in their partners’ cervico-vaginal secretions. This may have important implications for the biology of penile HIV acquisition. 相似文献
34.
限气贮藏对猕猴桃果实总淀粉酶和多聚半乳糖醛酸酶活性的影响 总被引:3,自引:0,他引:3
秦美猕猴桃于常温下采用限气贮藏时与对照相比,果实总淀粉酶和多聚半乳糖醛酸酶活性降低,淀粉含量和非水溶性果胶含量的下降减缓,水溶性果胶含量的增加变慢。因此,限气贮藏的猕猴桃果实能保持较高的硬度。 相似文献
35.
通过对猕猴桃果实成熟主要指标的测定,确定了秦美适宜采收期为10月3日至12日,西选1号和海沃德为10月下旬。这时果实可溶性固形物含量为6.5─9%,硬度12─16kg/cm2。猕猴桃贮鲜技术在1992/93年度中试(示范)成功的基础上,1993/94年度在64t果实上的应用又取得了好结果。秦美贮藏157天,果实新鲜,完好果和商品果分别为96.6%和97.4%。果实在贮藏期间硬度逐渐降低,由采收时12─16kg/cm2下降到1.6kg/m2;淀粉在酶的作用下不断转化为可溶性糖,可溶性固形物由采收时6.5─9%增加到13.7%。简易降温库成本低,可利用自然低温设施,果实在箱袋内加保鲜剂后置该库内有利于延长猕猴桃贮藏保鲜期。 相似文献
36.
Meigui Zhang Jing Li Ruixia Ma Jiahui Xi Lili Xi Baoxin Zhang Jing Tian Zhongtian Bai 《化学与生物多样性》2023,20(7):e202300050
Background : Liver cancer is an extremely common cancer with the highest mortality rate and poor prognosis. Owing to their low systemic toxicity and few side effects, natural compounds may provide better therapeutic effects for patients. (2E)-1-(2,4,6-trimethoxyphenyl)-3-(4-chlorophenyl)prop-2-en-1-one (TMOCC), a chalcone derivative, exhibits cytotoxicity towards many tumor cells. However, the anticancer mechanism of TMOCC has not been elucidated in human hepatocellular carcinoma (HCC). Methods : Cell Counting Kit-8 and colony formation assays were used to evaluate the effects of TMOCC on viability and proliferation. Mitochondrial transmembrane potential and flow cytometry assays were used to detect apoptosis. The expression levels of proteins related to apoptosis, the RAS-ERK and AKT/FOXO3a signaling pathways were assessed using western blot. Potential targets of TMOCC were detected using molecular docking analysis. Results : TMOCC inhibited viability and proliferation, and induced the loss of mitochondrial transmembrane potential, apoptosis and DNA double-strand breaks in both HCC cells. The RAS-ERK and AKT/FOXO3a signaling pathways were suppressed by TMOCC. Finally, ERK1, PARP-1, and BAX were identified as potential targets of TMOCC. Conclusion : Taken together, our results show that TMOCC promotes apoptosis by suppressing the RAS-ERK and AKT/FOXO3a signaling pathways. TMOCC may be a potential multi-target compound that is effective against liver cancer. 相似文献