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101.
CMCase production by Spicellum roseum in liquid and solid culture   总被引:1,自引:0,他引:1  
Summary CMCase was produced by 7 strains of Spicellum roseum in both liquid and wheat bran solid substrate cultures. No growth occurred above 35°C. Maximum enzyme production occurred at 30°C, whereas best enzyme activity occurred at pH 5.0 and 50°C. In liquid cultures of S. roseum, NRRL strains 13103, 13104, and 13106 produced activities of ca. 1.1, 1.5, and 1.5 mg glucose per hr/ml culture supernate at 1 week and 2.9, 1.5, and 2.1, respectively at 3 weeks compared to Trichoderma reesei NRRL 11236 (MCG77), which produced activities of 2.8 and 1.3 at 1 and 3 weeks.The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned.  相似文献   
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We assessed the role of CCR5+/CCR6+/CD11b+/CD11c+ dendritic cells (DCs) for induction of ovalbumin (OVA)-specific antibody (Ab) responses following mucosal immunization. Mice given nasal OVA plus an adenovirus expressing Flt3 ligand (Ad-FL) showed early expansion of CCR5+/CCR6+/CD11b+/CD11c+ DCs in nasopharyngeal-associated lymphoid tissue (NALT) and cervical lymph nodes (CLNs). Subsequently, this DC subset became resident in submandibular glands (SMGs) and nasal passages (NPs) in response to high levels of CCR-ligands produced in these tissues. CD11b+/CD11c+ DCs were markedly decreased in both CCR5−/− and CCR6−/− mice. Chimera mice reconstituted with bone marrow cells from CD11c-diphtheria toxin receptor (CD11c-DTR) and CCR5−/− or CD11c-DTR and CCR6−/− mice given nasal OVA plus Ad-FL had elevated plasma IgG, but reduced IgA as well as low anti-OVA secretory IgA (SIgA )Ab responses in saliva and nasal washes. These results suggest that CCR5+CCR6+ DCs play an important role in the induction of Ag-specific SIgA Ab responses.  相似文献   
104.
105.

Background

The appropriate use of generic preference-based measures determines the accuracy of disease assessment and further decision on healthcare policy using quality adjusted life years. The discriminative capacity of different instruments would differ across disease groups. Our study was to examine the difference in utility scores for COPD patients measured by EQ-5D and SF-6D and to assist the choice of a proper instrument in this disease group.

Methods

Differences of mean utility scores of EQ-5D and SF-6D in groups defined by socio-demographic characteristics, comorbidities, health service utilisation and severity of illness were tested using Mann-Whitney test, t-test, Kruskal-Wallis test, Pearson’s correlation coefficient and ANOVA, as appropriate. The discriminative properties of the two instruments were compared against indicators of quality of life using receiver operating characteristic curves. The statistical significance of the area under the curves (AUC) was tested by ANOVA and F-statistics used to compare the efficiency with which each instrument discriminated between disease severity groups.

Results

Mean utility scores of EQ-5D and SF-6D were 0.644 and 0.629 respectively in the 154 subjects included in the analysis. EQ-5D scores were significantly higher than SF-6D in groups less severe and these differences corresponded to a minimally important difference of greater than 0.03 (p<0.001). EQ-5D and SF-6D scores were strongly correlated across the whole sample (r = 0.677, p<0.001) and in pre-defined groups (r>0.5 and p<0.05 for all correlation coefficients). AUCs were above 0.5 against the indicators of health-related quality of life for both instruments. F-ratios suggested SF-6D was more efficient in discriminating cases of different disease severity than EQ-5D.

Conclusions

Both EQ-5D and SF-6D appeared to be valid preference-based measures in Chinese COPD patients. SF-6D was more efficient in detecting differences among subgroups with differing health status. EQ-5D and SF-6D measured different things and might not be used interchangeably in COPD patients.  相似文献   
106.
107.
In the present study, we analyzed the functional profile of CD8+ T-cell responses directed against autologous transmitted/founder HIV-1 isolates during acute and early infection, and examined whether multifunctionality is required for selection of virus escape mutations. Seven anti-retroviral therapy-naïve subjects were studied in detail between 1 and 87 weeks following onset of symptoms of acute HIV-1 infection. Synthetic peptides representing the autologous transmitted/founder HIV-1 sequences were used in multiparameter flow cytometry assays to determine the functionality of HIV-1-specific CD8+ T memory cells. In all seven patients, the earliest T cell responses were predominantly oligofunctional, although the relative contribution of multifunctional cell responses increased significantly with time from infection. Interestingly, only the magnitude of the total and not of the poly-functional T-cell responses was significantly associated with the selection of escape mutants. However, the high contribution of MIP-1β-producing CD8+ T-cells to the total response suggests that mechanisms not limited to cytotoxicity could be exerting immune pressure during acute infection. Lastly, we show that epitope entropy, reflecting the capacity of the epitope to tolerate mutational change and defined as the diversity of epitope sequences at the population level, was also correlated with rate of emergence of escape mutants.  相似文献   
108.

Background

Ovarian cancer is one of the most lethal malignancies in women, as it is frequently detected at an advanced stage, and cancers often become refractory to chemotherapy. Evidence suggests that dysregulation of pro-apoptotic genes plays a key role in the onset of chemoresistance. The secreted Frizzled-Related Protein (sFRP) family is pro-apoptotic and also a negative modulator of the Wnt signalling cascade. Studies have demonstrated that the re-expression of sFRPs, in particular sFRP4, is associated with a better prognosis, and that experimentally induced expression results in cell death.

Results

In vitro experimental models determined that sFRP4 was differentially expressed in chemosensitive (A2780) and chemoresistant (A2780 ADR and A2780 Cis) ovarian cell lines, with chemosensitive cells expressing significantly higher levels of sFRP4. Transfection of the chemoresistant cell lines with sFRP4 significantly increased their sensitivity to chemotherapy. Conversely, silencing of sFRP4 expression in the chemosensitive cell line resulted in a corresponding increase in chemoresistance. Comparison of sFRP4 expression in tumour biopsies revealed a positive trend between sFRP4 expression and tumour grade, with mucinous cyst adenocarcinomas exhibiting significantly decreased sFRP4 levels compared to mucinous borderline tumours.

Conclusions

This study indicates a role for sFRP4 as a predictive marker of chemosensitivity in ovarian cancer and suggests that this pathway may be worth exploiting for novel therapies.  相似文献   
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110.
DNA synthesis and the control of embryonic gene expression in C. elegans   总被引:9,自引:0,他引:9  
L G Edgar  J D McGhee 《Cell》1988,53(4):589-599
DNA synthesis in each cell lineage of the early C. elegans embryo was measured using microspectrofluorimetry. Aphidicolin was shown to inhibit DNA synthesis almost instantly and completely. Aphidicolin was then used to investigate how DNA synthesis controls expression of two biochemical markers that appear at different times during gut development: gut granules and a carboxylesterase. We show that marker expression is controlled neither by reaching the normal DNA: cytoplasm ratio, by counting the normal number of rounds of DNA synthesis, nor by a simple lengthening of the cell cycle. Instead, expression of both gut markers requires a short period of DNA synthesis in the first cell cycle after the gut has been clonally established.  相似文献   
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