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1.
We have previously suggested that thymosin 1 (thy1), an immunomodulating thymic hormone, can activate tumor-associated macrophages to a tumoricidal state in a murine model bearing a transplantable T-cell lymphoma of spontaneous origin designated as Dalton's lymphoma (DL). Since tumor-infiltrating dendritic cells (DC) also play an important role in the host's antitumor response and are as such in an immunocompromised state in a tumor-bearing host, in the present investigation we studied if thy1 is able to influence the differentiation of tumor-associated macrophages (TAM) into DC with granulocyte macrophage colony stimulating factor (GM-CSF), interleukin (IL)-4 and tumor necrosis factor (TNF) and whether these TAM-derived DC show enhanced antitumor activity. It was observed that DC generated from thy1-administered tumor-bearing mice showed augmented antitumor activity in vitro. Adoptive immunotherapy using TAM-derived DC showed a significant delay in the tumor growth and a prolongation of the survival time in tumor-bearing mice. DC obtained from TAM of thy1-administered mice also produced an enhanced amount of cytokines like IL-1 and TNF-. This is the first study of its kind regarding the effect of thy1 on the differentiation of DC from TAM and the role of TAM-derived DC in tumor progression.  相似文献   
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Since the summer of 1982, we have cultured patient specimens for Lyme disease spirochetes. Of 118 patients cultured, four specimens yielded spirochetes: two from blood, one from a skin biopsy specimen of erythema chronicum migrans (ECM), and one from cerebrospinal fluid. All four isolates appeared identical when examined with a monoclonal antibody. However, attempts to recover the spirochete from synovium or synovial fluid were unsuccessful. In addition, the organism could not be visualized in skin or synovial biopsy specimens using the avidin-biotin peroxidase complex detection system. Thus, the current yield in culturing spirochetes from patients is quite low, and it is not yet known whether the organism is still alive later in the disease when arthritis is present.  相似文献   
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1,2,3-Triazole based molecules are useful pharmacophores for several DNA-alkylating and cross-linking agents. A series of A/C8, C/C2 and A/C8-C/C2-linked 1,2,3-triazole-PBD conjugates have been synthesized by employing 'click' chemistry. These molecules have exhibited promising DNA-binding affinity and anticancer activity in selected human cancer cell lines.  相似文献   
5.

Background and Aims

microRNAs (miRNAs) are small, endogenous non-coding RNAs that regulate metabolic processes, including obesity. The levels of circulating miRNAs are affected by metabolic changes in obesity, as well as in diet-induced weight loss. Circulating miRNAs are transported by high-density lipoproteins (HDL) but the regulation of HDL-associated miRNAs after diet-induced weight loss has not been studied. We aim to determine if HDL-associated miR-16, miR-17, miR-126, miR-222 and miR-223 levels are altered by diet-induced weight loss in overweight and obese males.

Methods

HDL were isolated from 47 subjects following 12 weeks weight loss comparing a high protein diet (HP, 30% of energy) with a normal protein diet (NP, 20% of energy). HDL-associated miRNAs (miR-16, miR-17, miR-126, miR-222 and miR-223) at baseline and after 12 weeks of weight loss were quantified by TaqMan miRNA assays. HDL particle sizes were determined by non-denaturing polyacrylamide gradient gel electrophoresis. Serum concentrations of human HDL constituents were measured immunoturbidometrically or enzymatically.

Results

miR-16, miR-17, miR-126, miR-222 and miR-223 were present on HDL from overweight and obese subjects at baseline and after 12 weeks of the HP and NP weight loss diets. The HP diet induced a significant decrease in HDL-associated miR-223 levels (p = 0.015), which positively correlated with changes in body weight (r = 0.488, p = 0.032). Changes in miR-223 levels were not associated to changes in HDL composition or size.

Conclusion

HDL-associated miR-223 levels are significantly decreased after HP diet-induced weight loss in overweight and obese males. This is the first study reporting changes in HDL-associated miRNA levels with diet-induced weight loss.  相似文献   
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2,4,6-三硝基甲苯(TNT)作为一种广泛使用的含能材料,发挥巨大作用的同时也给环境带来了严重的污染,对人类健康构成一定威胁。目前国内外的TNT处置主要有物理、化学、生物及酶法等方法,其中酶法作为一种新兴的方法,显示了良好的应用潜力,受到研究者的广泛关注,。比较了各类处理方法的优缺点,重点介绍近年来涉及TNT降解的酶学研究进展,并对酶法在TNT废水处理和土壤修复中的应用前景进行展望。  相似文献   
8.
Ephedra foliata Boiss. & Kotschy ex Boiss., (family – Ephedraceae), is an ecologically and economically important threatened Gymnosperm of the Indian Thar Desert. A method for micropropagation of E. foliata using nodal explant of mature female plant has been developed. Maximum bud-break (90 %) of the explant was obtained on MS medium supplemented with 1.5 mg l−1 of benzyl adenine (BA) + additives. Explant produces 5.3 ± 0.40 shoots from single node with 3.25 ± 0.29 cm length. The multiplication of shoots in culture was affected by salt composition of media, types and concentrations of plant growth regulators (PGR’s) and their interactions, time of transfer of the cultures. Maximum number of shoots (26.3 ± 0.82 per culture vessel) were regenerated on MS medium modified by reducing the concentration of nitrates to half supplemented with 200 mg l−1 ammonium sulphate {(NH4) 2SO4} (MMS3) + BA (0.25 mg l−1), Kinetin (Kin; 0.25 mg l−1), Indole-3-acetic acid (IAA; 0.1 mg l−1) and additives. The in vitro produced shoots rooted under ex vitro on soilrite moistened with one-fourth strength of MS macro salts in screw cap bottles by treating the shoot base (s) with 500 mg l−1 of Indole-3-butyric acid (IBA) for 5 min. The micropropagated plants were hardened in the green house. The described protocol can be applicable for (i) large scale plant production (ii) establishment of plants in natural habitat and (iii) germplasm conservation of this endemic Gymnosperm of arid regions.  相似文献   
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Himalayan alder species are proven to be very useful in traditional as well as contemporary agroforestry practice. These nitrogen-fixing trees are also useful in the land restoration. Therefore, understanding the distribution of Himalayan alder and the potential zone for plantation is meaningful in the agroforestry sector. Suitable climatic zones of Alnus spp. were modelled in MaxEnt software using a subset of least correlated bioclimatic variables for current conditions (1950-2000), topographic variables (DEM derived) and Landuse Landcover (LULC) data. We generated several models and selected the best model against random models using ANOVA and t-test. The environmental variables that best explained the current distribution of the species were identified and used to project into the future. For future projections, ensemble scenarios of climate change projection derived from the results of 19 Earth System Models (ESM) were used. Our model revealed that the most favorable conditions for Alnus nepalensis are in central Nepal in the moist north-west facing slope, whereas for Alnus nitida they are in western Nepal. The major climatic factor that contributes to Alnus species distribution in Nepal appears to be precipitation during the warmest quarter for A. nepalensis and precipitation during the driest quarter for A. nitida. Future projections revealed changes in the probability distribution of these species, as well as where they need conservation and where they can be planted. Also, our model predicts that the distribution of Alnus spp. in hilly regions will remain unchanged, and therefore may represent sites that can be used to revitalize traditional agroforestry systems and extract source material for land restoration.  相似文献   
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