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The bacterial superantigen staphylococcal enterotoxin B (SEB) is a potent inducer of cytotoxic T-cell activity and cytokine production in vivo. We investigated the possibility of the therapeutic application of SEB in patients with fibrosarcoma. The anti-tumor effect of SEB in mice with inoculated fibrosarcoma (WEHI-164) was examined by intravenous (IV) and intratumoral (IT) injection and the sizes of the inoculated tumors, IFN-γ production, and CD4+/CD8+ T cell infiltration were determined. The inoculated tumors were also examined histologically. In the mice in the IV-injected group, a significant reduction (P < 0.02) of tumor size was observed in comparison with mice in the IT-injected and control groups. Furthermore, the mice in the IV-injected group showed significantly higher levels of IFN-γ (P < 0.009) and CD4+/CD8+ T cell infiltration when compared with the other groups (P < 0.02). A significantly higher frequency of necrosis in tumor tissues was also observed in mice in the IV-injected group (P < 0.05). Our present findings suggest that tumor cell death is caused by increased cytotoxic T-cell activity and cytokine levels in response to the IV injection of SEB and that SEB may be a good option for use as a novel therapy in patients with fibrosarcoma. An erratum to this article can be found at  相似文献   
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Plant secondary metabolism evolved in the context of highly organized and differentiated cells and tissues, featuring massive chemical complexity operating under tight environmental, developmental and genetic control. Biotechnological demand for natural products has been continuously increasing because of their significant value and new applications, mainly as pharmaceuticals. Aseptic production systems of plant secondary metabolites have improved considerably, constituting an attractive tool for increased, stable and large-scale supply of valuable molecules. Surprisingly, to date, only a few examples including taxol, shikonin, berberine and artemisinin have emerged as success cases of commercial production using this strategy. The present review focuses on the main characteristics of plant specialized metabolism and their implications for current strategies used to produce secondary compounds in axenic cultivation systems. The search for consonance between plant secondary metabolism unique features and various in vitro culture systems, including cell, tissue, organ, and engineered cultures, as well as heterologous expression in microbial platforms, is discussed. Data to date strongly suggest that attaining full potential of these biotechnology production strategies requires being able to take advantage of plant specialized metabolism singularities for improved target molecule yields and for bypassing inherent difficulties in its rational manipulation.  相似文献   
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Molecular Biology Reports - Cystinuria is an autosomal recessive defect in reabsorptive transport of cystine and the dibasic amino acids ornithine, arginine, and lysine from renal tubule and small...  相似文献   
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Journal of Plant Growth Regulation - This study investigated the effect of irrigation regimes and the foliar application of salicylic acid (SA) and spermine (SPM) on the content of essential oil...  相似文献   
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Due to the association of oxidative stress and telomere shortening, it was aimed in the present study to investigate the possibility whether cyclosporine‐A exerts its nephrotoxic side effects via induction of oxidative stress‐induced renal telomere shortening and senescent phenotype in renal tissues of rats. Renal oxidative stress markers, 8‐hydroxydeoxyguanosine, malondialdehyde, and protein carbonyl groups were measured by standard methods. Telomere length and telomerase activity were also evaluated in kidney tissue samples. Results showed that cyclosporine‐A treatment significantly (< 0.05) enhanced renal malondialdehyde, 8‐hydroxydeoxyguanosine, and protein carbonyl groups levels, decreased renal telomere length, and deteriorated renal function compared with the controls. Renal telomerase activity was not affected by cyclosporine‐A. Renal telomere length could be considered as an important parameter of both oxidative stress and kidney function. Telomere shortening and accelerated kidney aging may be caused by cyclosporine‐induced oxidative stress, indicating the potential mechanism of cyclosporine‐induced nephrotoxicity.  相似文献   
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Five percent of all epilepsy cases are attributed to traumatic brain injury (TBI), which are known as post-traumatic epilepsy (PTE). Finding preventive strategies for PTE is valuable. Remarkable feature of TBI is activation of microglia and subsequent neuroinflammation, which provokes epileptogenesis. The toll-like receptor agonists monophosphoryl lipid A (MPL) and tri-palmitoyl-S-glyceryl-cysteine (Pam3Cys) are safe, well-tolerated and effective adjuvants existing in prophylactic human vaccines. We examined the impact of early injection of MPL and Pam3Cys to rats, on the rate of kindled seizures acquisition following TBI. Rats received a single dose (1 µg/rat) of MPL or Pam3Cys through intracerebroventricular injection. 5 days later, trauma was exerted to temporo-parietal cortex of rats by controlled cortical impact device. After 24 h, traumatic rats underwent amygdala kindling. Brain level of the inflammatory cytokine tumor necrosis factor-alpha (TNF-α) was also measured in traumatic rats by immunoblotting. Compared to non-traumatic (sham-operated) rats, traumatic rats showed three times lower seizure threshold (133?±?5 µA vs. 416.3?±?16 µA, p?<?0.001); about three times less number of stimuli to become kindled (5?±?1 vs. 14?±?2, p?<?0.01); longer duration of kindled seizure parameters including entire seizure behavior, generalized seizures, and afterdischarges (p?<?0.001); and a two times increase in the TNF-α level. MPL and Pam3Cys did not change kindling rate and the seizure parameters in sham-operated rats. The MPL- and Pam3Cys-pretreated traumatic rats displayed seizure threshold, speed of kindling, and duration of kindled seizure parameters, similar to the non-traumatic rats. Pretreatment by MPL and Pam3Cys prevented the increase in TNF-α level by trauma. Given that MPL and Pam3Cys currently have clinical use as well-tolerated vaccines with reliable safety, they have the potential to be used in prevention of PTE.  相似文献   
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