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101.
Reviews in Environmental Science and Bio/Technology - The depletion of fossil fuel reserves and greenhouse gas emissions led to limit the use of fossil fuels, including natural gas, coal, or...  相似文献   
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Agonistic anti-4-1BB Ab is known to ameliorate experimental autoimmune encephalomyelitis. 4-1BB triggering typically leads to the expansion of CD8(+) T cells, which produce abundant IFN-γ, and this in turn results in IDO-dependent suppression of autoimmune responses. However, because neutralization of IFN-γ or depletion of CD8(+) T cell only partially abrogates the effect of 4-1BB triggering, we sought to identify an additional mechanism of 4-1BB-triggered suppression of autoimmune responses using IFN-γ- or IFN-γR-deficient mice. 4-1BB triggering inhibited the generation of Th17 cells that is responsible for experimental autoimmune encephalomyelitis induction and progression, and increased Foxp3(+)CD4(+) regulatory T (Treg) cells, particularly among CD4(+) T cells. This was not due to a direct effect of 4-1BB signaling on CD4(+) T cell differentiation: 4-1BB signaling not only reduced Th17 cells and increased Treg cells in wild-type mice, which could be due to IFN-γ production by the CD8(+) T cells, but also did so in IFN-γ-deficient mice, in that case by downregulating IL-6 production. These results show that although secondary suppressive mechanisms evoked by 4-1BB triggering are usually masked by the strong effects of IFN-γ, 4-1BB signaling seems to modulate autoimmune responses by a number of mechanisms, and modulation of the Th17 versus Treg cell balance is one of those mechanisms.  相似文献   
104.
Pandemic and seasonal influenza viruses cause considerable morbidity and mortality in the general human population. Protection from severe disease may result from vaccines that activate antigen-presenting DC for effective stimulation of influenza-specific memory T cells. Special attention is paid to vaccine-induced CD8+ T-cell responses, because they are mainly directed against conserved internal influenza proteins thereby presumably mediating cross-protection against circulating seasonal as well as emerging pandemic virus strains. Our study showed that influenza whole virus vaccines of major seasonal A and B strains activated DC more efficiently than those of pandemic swine-origin H1N1 and pandemic-like avian H5N1 strains. In contrast, influenza split virus vaccines had a low ability to activate DC, regardless which strain was investigated. We also observed that whole virus vaccines stimulated virus-specific CD8+ memory T cells much stronger compared to split virus counterparts, whereas both vaccine formats activated CD4+ Th cell responses similarly. Moreover, our data showed that whole virus vaccine material is delivered into the cytosolic pathway of DC for effective activation of virus-specific CD8+ T cells. We conclude that vaccines against seasonal and pandemic (-like) influenza strains that aim to stimulate cross-reacting CD8+ T cells should include whole virus rather than split virus formulations.  相似文献   
105.
4-1BB (CD137) is an important T cell activating molecule. Here we report that it also promotes development of a distinct B cell subpopulation co-expressing PDCA-1. 4-1BB is expressed constitutively, and its expression is increased when PDCA-1+ B cells are activated. We found that despite a high level of surface expression of 4-1BB on PDCA-1+ B cells, treatment of these cells with agonistic anti-4-1BB mAb stimulated the expression of only a few activation markers (B7-2, MHC II, PD-L2), cytokines (IL-12p40/p70), and chemokines (MCP-1, RANTES), as well as sTNFR1, and the immunosuppressive enzyme, IDO. Although the PDCA-1+ B cells stimulated by anti-4-1BB expressed MHC II at high levels and took up antigens efficiently, Ig class switching was inhibited when they were pulsed with T-independent (TI) or T-dependent (TD) Ags and adoptively transferred into syngeneic recipients. Furthermore, when anti-4-1BB-treated PDCA-1+ B cells were pulsed with OVA peptide and combined with Vα2+CD4+ T cells, Ag-specific cell division was inhibited both in vitro and in vivo. Our findings suggest that the 4-1BB signal transforms PDCA-1+ B cells into propagators of negative immune regulation, and establish an important role for 4-1BB in PDCA-1+ B cell development and function.  相似文献   
106.
In Drosophila multiple circadian oscillators and behavioral rhythms are known to exist, yet most previous studies that attempted to understand circadian entrainment have focused on the activity/rest rhythm and to some extent the adult emergence rhythm. Egg laying behavior of Drosophila females also follows circadian rhythmicity and has been seen to deviate substantially from the better characterized rhythms in a few aspects. Here we report the findings of our study aimed at evaluating how circadian egg laying rhythm in fruit flies Drosophila melanogaster entrains to time cues provided by light and temperature. Previous studies have shown that activity/rest rhythm of flies entrains readily to light/dark (LD) and temperature cycles (TC). Our present study revealed that egg laying rhythm of a greater percentage of females entrains to TC compared to LD cycles. Therefore, in the specific context of our study this result can be taken to suggest that egg laying clocks of D. melanogaster entrains to TC more readily than LD cycles. However, when TC were presented along with out-of-phase LD cycles, the rhythm displayed two peaks, one occurring close to lights-off and the other near the onset of low temperature phase, indicating that upon entrainment by TC, LD cycles may be able to exert a greater influence on the phase of the rhythm. These results suggest that temperature and light associatively entrain circadian egg laying clocks of Drosophila.  相似文献   
107.
Griseofulvin, an antifungal agent, is a BCS class II drug slowly, erratically, and incompletely absorbed from the gastrointestinal tract in humans. The clinical failure of the conventional oral therapy of griseofulvin is most likely attributed to its poor solubility and appreciable inter- and intra-subject variation in bioavailability from different commercial products. Moreover, the conventional oral therapy is associated with numerous adverse effects and interactions with other drugs. The purpose of the study was to formulate a topical application of griseofulvin which would deliver the drug locally in a therapeutically effective concentration. Griseofulvin was solubilized in ethanol, d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS), and combinations of ethanol with varying amounts of TPGS; then, it was incorporated in the Carbopol (980 NF) base. The formulations were characterized and evaluated ex vivo using Laca mice skin, microbiologically against Microsporum gypseum and Microsporum canis and clinically in a small group of patients. The current study suggested that TPGS and ethanol synergistically enhanced the drug permeation and drug retention in the skin. The selected formulation F VII was found to be effective against M. gypseum and M. canis, non-sensitizing, histopathologically safe, stable at 4°C, 25°C, and 40°C with respect to percent drug content, permeation characteristics, pH, transparency, feel, viscosity, and clinically effective in a small group of subjects. The proposed topical formulation of griseofulvin may be an effective and convenient alternative to the currently available oral therapy for the treatment of superficial fungal infections.  相似文献   
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109.
Image analysis was used to quantify the activity of a temperature-sensitive macromelanophore-determining allele in sailfin mollies as the percentage of the body surface area covered by macromelanophores. Fish heterozygous for the macromelanophore-determining allele produced very few macromelanophores when raised at either 25 or 28 degrees C, even after more than 200 days. In contrast, the mean percent coverage for genetically identical fish raised at 22 degrees C increased steadily throughout the course of the experiment. Production of macromelanophores was sex influenced, with greater expressivity seen in males. At 22 degrees C, the mean percent coverages had significantly diverged between males and females by the age of 201 days. From that point on, the percent macromelanophore coverage of the males was consistently significantly higher than that of the females. The tendency to produce greater melanization at cooler temperatures is not the result of a heat-sensitive tyrosinase enzyme, as is the case in mammals carrying the Himalayan allele. In mollies, the activity of tyrosinase increases between 22 and 29 degrees C. We hypothesize that production of macromelanophores is under the control of a proto-oncogene.  相似文献   
110.
Wang H  Dass C 《Peptides》2002,23(12):2143-2150
A method based upon a combination of fast high-performance liquid chromatography (HPLC) and electrospray ionization (ESI)–mass spectrometry (MS) is developed for the analysis of bioactive peptides in bovine adrenal medulla. The fast HPLC uses a short column (33 mm×4.6 mm) packed with nonporous silica-based C-18 stationary phase. Prior to HPLC separation, the medulla was homogenized and the peptide-rich fraction was isolated from it by solid-phase extraction. In-source collision-induced dissociation and tandem MS were used to obtain the sequence of the suspected peptides. Several peptides, including Met–Enk, Leu–Enk, Leu–Enk–Lys, bovine adrenal medullary (BAM)-12 (Met–Enk–RRVGRPE), Leu–Enk–Arg, and YGGT, were unambiguously identified. The first four peptides are the products of proenkephalin A precursor protein and Leu–Enk–Arg belongs to the dynorphin family and is derived from proenkephalin B (prodynorphin) precursor. The database search revealed that YGGT is a part of the sequence of five different precursor proteins.  相似文献   
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