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31.
Herpes simplex virus type 1 (HSV-1) infection induces profound nucleolar modifications at the functional and organizational levels, including nucleolar invasion by several viral proteins. One of these proteins is US11, which exhibits several different functions and displays both cytoplasmic localization and clear nucleolar localization very similar to that of the major multifunctional nucleolar protein nucleolin. To determine whether US11 interacts with nucleolin, we purified US11 protein partners by coimmunoprecipitations using a tagged protein, Flag-US11. From extracts of cells expressing Flag-US11 protein, we copurified a protein of about 100 kDa that was further identified as nucleolin. In vitro studies have demonstrated that nucleolin interacts with US11 and that the C-terminal domain of US11, which is required for US11 nucleolar accumulation, is sufficient for interaction with nucleolin. This association was confirmed in HSV-1-infected cells. We found an increase in the nucleolar accumulation of US11 in nucleolin-depleted cells, thereby revealing that nucleolin could play a role in US11 nucleocytoplasmic trafficking through one-way directional transport out of the nucleolus. Since nucleolin is required for HSV-1 nuclear egress, the interaction of US11 with nucleolin may participate in the outcome of infection.  相似文献   
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The viral infectivity factor (Vif), one of the six HIV-1 auxiliary genes, is absolutely necessary for productive infection in primary CD4-positive T lymphocytes and macrophages. Vif overcomes the antiviral function of the host factor APOBEC3G. To better understand this mechanism, it is of interest to characterize cellular proteins that interact with Vif and may regulate its function. Here, we show that Vif binds to hNedd4 and AIP4, two HECT E3 ubiquitin ligases. WW domains present in those HECT enzymes contribute to the binding of Vif. Moreover, the region of Vif, which includes amino acids 20-128 and interacts with the hNedd4 WW domains, does not contain proline-rich stretches. Lastly, we show that Vif undergoes post-translational modifications by addition of ubiquitin both in cells overexpressing Vif and in cells expressing HIV-1 provirus. Vif is mainly mono-ubiquitinated, a modification known to address the Gag precursor to the virus budding site.  相似文献   
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Hydrated monoolein forms the cubic-Pn3m mesophase that has been used for in meso crystallization of membrane proteins. The crystals have subsequently provided high-resolution structures by crystallographic means. It is possible that the hosting cubic phase created by monoolein alone, which itself is not a common membrane component, will limit the range of membrane proteins crystallizable by the in meso method. With a view to expanding the range of applicability of the method, we investigated by x-ray diffraction the degree to which the reference cubic-Pn3m phase formed by hydrated monoolein could be modified by other lipid types. These included phosphatidylcholine (PC), phosphatidylethanolamine, phosphatidylserine, cardiolipin, lyso-PC, a polyethylene glycol-lipid, 2-monoolein, oleamide, and cholesterol. The results show that all nine lipids were accommodated in the cubic phase to some extent without altering phase identity. The positional isomer, 2-monoolein, was tolerated to the highest level. The least well tolerated were the anionic lipids, followed by lyso-PC. The others were accommodated to the extent of 20-25 mol %. Beyond a certain concentration limit, the lipid additives either triggered one or a series of phase transitions or saturated the phase and separated out as crystals, as seen with oleamide and cholesterol. The series of phases observed and their order of appearance were consistent with expectations in terms of interfacial curvature changes. The changes in phase type and microstructure have been rationalized on the basis of lipid molecular shape, interfacial curvature, and chain packing energy. The data should prove useful in the rational design of cubic phase crystallization matrices with different lipid profiles that match the needs of a greater range of membrane proteins.  相似文献   
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Summary Thirty-nine patients with squamous cell carcinoma of the bronchus were randomized into two groups after radical surgery. The first group of 18 patients received 75 mg of living BCG on a scratched area once a week; the second group of 21 patients received no further treatment. After 2 years 3 patients of the group treated with BCG are dead and 1 is in relapse; 8 patients of the control group are dead and 2 are in relapse.In this study the hope of survival for more than 2 years for patients with squamous cell carcinoma of the bronchus is 66% in the group of patients treated with BCG, and 38% in the control group. From these results we can see the beneficial effect of BCG as a complementary treatment of surgery for patients with squamous cell carcinoma of the bronchus.  相似文献   
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Summary The effect of geomagnetic force on the light-withdrawal reflex of earthworms, Lumbricus terrestris, L., was investigated during the autumn of 1968. The reactions of worms kept in the earth's magnetic field were timed beginning at 12:00 and at 20:00, E.S.T. on each of 63 days; the same was done for worms maintained in a field whose intensity was essentially zero. The worms in the earth's field withdrew from light significantly faster at night then at midday. No significant difference between the mean reaction times at 12:00 and those of the evening were found for the animals which lived and were tested in the greatly reduced magnetic field. Therefore, geomagnetism does have some effect on the circadian difference in reaction rates in this species.
Zusammenfassung Die Wirkung des erdmagnetisohen Feldes auf die Lichtreaktion von Lumbricus terrestris wurde untersucht (Herbst 1968). Als Test wurde die Reaktion auf einen Lichtreiz verwendet. Ein Teil der Würmer wurde im natürlichen erdmagnetisehen Feld, ein anderer Teil in einem auf Null kompensierten Feld gehalten. Die Reaktionszeiten auf den Lichtreiz wurden bei beiden Gruppen um 12.00 und um 20.00 Uhr gemessen. Die Reaktionszeiten im natürlichen erdmagnetischen Feld waren abends signifikant (p=0,005) kürzer (7,2 sec) als mittags (8,9 sec). Im Feld, das nahezu auf Null kompensiert war, waren die Reaktionszeiten abends und mittags gleich (8,8 bzw. 8,7 sec). Der Erdmagnetismus hat also einen Einfluß auf die circadiane Differenz der Reaktionszeiten bei Lumbricus.
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Dermatophytoses include a wide variety of diseases involving glabrous skin, nails and hair. These superficial infections are a common cause of consultation in dermatology. In many cases, their diagnosis is not clinically obvious, and mycological analysis therefore is required. Direct microscopic examination of the samples using clearing agents provides a quick response to the clinician and is usually combined with cultures on specific media, which must be used to overcome the growth of contaminating moulds that may hamper the recovery of dermatophytes. Accurate identification of the causative agent (i.e. at the species level), currently based on morphological criteria, is necessary not only to initiate an appropriate treatment but also for setting prophylactic measures. However, conventional methods often lack sensitivity and species identification may require up to 4 weeks if subcultures are needed. Histological analysis, which is considered the “gold standard” for the diagnosis of onychomycoses, is seldom performed, and as direct examination, it does not allow precise identification of the pathogen. Nevertheless, a particular attention to the quality of clinical specimens is warranted. Moreover, the sensitivity of direct examination may be greatly enhanced by the use of fluorochromes such as calcofluor white. Likewise, sensitivity of the cultures could be enhanced by the use of culture media containing antifungal deactivators. With the generalization of molecular identification by gene sequencing or MALDI-TOF mass spectrometry, the contribution of historical biochemical or physiological tests to species identification of atypical isolates is now limited. Nevertheless, despite the recent availability of several PCR-based kits and an extensive literature on molecular methods allowing the detection of fungal DNA or both detection and direct identification of the main dermatophyte species, the biological diagnosis of dermatophytosis in 2016 still relies on both direct examination and cultures of appropriate clinical specimens.  相似文献   
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Human T-cell leukemia virus-1 (HTLV-1) causes adult T-cell leukemia/lymphoma, which is an aggressive peripheral T-cell neoplasm. Insufficient T-cell response to HTLV-1 is a potential risk factor in adult T-cell leukemia/lymphoma. Efficient induction of antigen-specific cytotoxic T lymphocytes is important for immunological suppression of virus-infected cell proliferation and oncogenesis, but efficient induction of antigen-specific cytotoxic T lymphocytes has evaded strategies utilizing poorly immunogenic free synthetic peptides. Here, we examined the efficient induction of an HTLV-1-specific CD8+ T-cell response by oligomannose-coated liposomes (OMLs) encapsulating the human leukocyte antigen (HLA)-A*0201-restricted HTLV-1 Tax-epitope (OML/Tax). Immunization of HLA-A*0201 transgenic mice with OML/Tax induced an HTLV-1-specific gamma-interferon reaction, whereas immunization with epitope peptide alone induced no reaction. Upon exposure of dendritic cells to OML/Tax, the levels of CD86, major histocompatibility complex class I, HLA-A02 and major histocompatibility complex class II expression were increased. In addition, our results showed that HTLV-1-specific CD8+ T cells can be efficiently induced by OML/Tax from HTLV-1 carriers compared with epitope peptide alone, and these HTLV-1-specific CD8+ T cells were able to lyse cells presenting the peptide. These results suggest that OML/Tax is capable of inducing antigen-specific cellular immune responses without adjuvants and may be useful as an effective vaccine carrier for prophylaxis in tumors and infectious diseases by substituting the epitope peptide.  相似文献   
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