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61.
MPT63 protein is found only in Mycobacterium tuberculosis complex, including M. tuberculosis and M. bovis. Detection of MPT63‐specific IFN‐γ‐secreting T cells could be useful for the diagnosis of tuberculosis (TB) diseases. In the present study, the HLA‐A*0201 restriction of ten predicted MPT63‐derived CD8 + T‐cell epitopes was assessed on the basis of T2 cell line and HLA‐A*0201 transgenic mice. The diagnostic potential of immunogenic peptides in active pulmonary TB patients was evaluated using an IFN‐γ enzyme‐linked immunospot assay. It was found that five peptides bound to HLA‐A*0201 with high affinity, whereas the remaining peptides exhibited low affinity for HLA‐A*0201. Five immunogenic peptides (MPT6318–26, MPT6329–37, MPT6320–28, MPT635–14 and MPT6310–19) elicited large numbers of cytotoxic IFN‐γ‐secreting T cells in HLA‐A*0201 transgenic mice. Each of the five immunogenic peptides was recognized by peripheral blood mononuclear cells from 45% to 73% of 40 HLA‐A*0201 positive TB patients. The total diagnostic sensitivity of the five immunogenic peptides was higher than that of a T‐SPOT.TB assay (based on ESAT‐6 and CFP‐10) (93% versus 90%). It is noticeable that the diagnostic sensitivity of the combination of five immunogenic peptides and T‐SPOT.TB assay reached 100%. These MPT63‐derived HLA‐A*0201‐restricted CD8 + T‐cell epitopes would likely contribute to the immunological diagnosis of M. tuberculosis infection and may provide the components for designing an effective TB vaccine.  相似文献   
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Feminist news media researchers have long contended that masculine news values shape journalists’ quotidian decisions about what is newsworthy. As a result, it is argued, topics and issues traditionally regarded as primarily of interest and relevance to women are routinely marginalised in the news, while men’s views and voices are given privileged space. When women do show up in the news, it is often as “eye candy,” thus reinforcing women’s value as sources of visual pleasure rather than residing in the content of their views. To date, evidence to support such claims has tended to be based on small-scale, manual analyses of news content. In this article, we report on findings from our large-scale, data-driven study of gender representation in online English language news media. We analysed both words and images so as to give a broader picture of how gender is represented in online news. The corpus of news content examined consists of 2,353,652 articles collected over a period of six months from more than 950 different news outlets. From this initial dataset, we extracted 2,171,239 references to named persons and 1,376,824 images resolving the gender of names and faces using automated computational methods. We found that males were represented more often than females in both images and text, but in proportions that changed across topics, news outlets and mode. Moreover, the proportion of females was consistently higher in images than in text, for virtually all topics and news outlets; women were more likely to be represented visually than they were mentioned as a news actor or source. Our large-scale, data-driven analysis offers important empirical evidence of macroscopic patterns in news content concerning the way men and women are represented.  相似文献   
65.
This study was conducted to identify the optimum pH range and the appropriate buffer for butyric acid production from rice straw by fermentation using an undefined mixed culture. A series of experiments conducted at pH levels of 5.0 ~ 7.0 showed that neutral pH improved rice straw conversion and consequently carboxylic acid production. The highest butyric acid production (up to 6.7 g/L) was achieved at pH of 6.0 ~ 6.5, while it was only 1.7 g/L without pH control or at pH 5.0. Another series of experiments conducted at pH 6.0 ~ 6.5 buffered with CaCO3, NaHCO3, NH4HCO3 and their combinations indicated that different buffers had different effects onthe product spectrum, and that CaCO3 combined with NaHCO3 was an effective buffer for butyric acid production. The highest total volatile fatty acids (about 12.6 g/L) production and one of the two highest butyric acid concentrations (about 7.6 g/L) were obtained by buffering with CaCO3 combined with NaHCO3. PCR-DGGE analysis revealed that different pH and buffers also influenced the microbial population distribution. Bacteria were suppressed at low pH, while the bacterial community structures at higher pH varied slightly. Overall, this study presents an alternative method for butyric acid production from lignocellulosic biomass without supplementary cellulolytic enzyme.  相似文献   
66.
The net photosynthetic rate (P N), the sample room CO2 concentration (CO2S) and the intercellular CO2 concentration (C i) in response to PAR, of C3 (wheat and bean) and C4 (maize and three-colored amaranth) plants were measured. Results showed that photorespiration (R p) of wheat and bean could not occur at 2 % O2. At 2 % O2 and 0 μmol mol?1 CO2, P N can be used to estimate the rate of mitochondrial respiration in the light (R d). The R d decreased with increasing PAR, and ranged between 3.20 and 2.09 μmol CO2 m?2 s?1 in wheat. The trend was similar for bean (between 2.95 and 1.70 μmol CO2 m?2 s?1), maize (between 2.27 and 0.62 μmol CO2 m?2 s?1) and three-colored amaranth (between 1.37 and 0.49 μmol CO2 m?2 s?1). The widely observed phenomenon of R d being lower than R n can be attributed to refixation, rather than light inhibition. For all plants tested, CO2 recovery rates increased with increasing light intensity from 32 to 55 % (wheat), 29 to 59 % (bean), 54 to 87 % (maize) and 72 to 90 % (three-colored amaranth) at 50 and 2,000 μmol m?2 s?1, respectively.  相似文献   
67.
Tropomyosins are actin-binding cytoskeletal proteins that play a pivotal role in regulating the function of actin filaments in muscle and non-muscle cells; however, the roles of non-muscle tropomyosins in mouse oocytes are unknown. This study investigated the expression and functions of non-muscle tropomyosin (Tpm3) during meiotic maturation of mouse oocytes. Tpm3 mRNA was detected at all developmental stages in mouse oocytes. Tpm3 protein was localized at the cortex during the germinal vesicle and germinal vesicle breakdown stages. However, the overall fluorescence intensity of Tpm3 immunostaining was markedly decreased in metaphase II oocytes. Knockdown of Tpm3 impaired asymmetric division of oocytes and spindle migration, considerably reduced the amount of cortical actin, and caused membrane blebbing during cytokinesis. Expression of a constitutively active cofilin mutant and Tpm3 overexpression confirmed that Tpm3 protects cortical actin from depolymerization by cofilin. The data indicate that Tpm3 plays crucial roles in maintaining cortical actin integrity and asymmetric cell division during oocyte maturation, and that dynamic regulation of cortical actin by Tpm3 is critical to ensure proper polar body protrusion.  相似文献   
68.
The wide application of multi-walled carbon nanotubes (MWCNT) has raised serious concerns about their safety on human health and the environment. However, the potential harmful effects of MWCNT remain unclear and contradictory. To clarify the potentially toxic effects of MWCNT and to elucidate the associated underlying mechanisms, the effects of MWCNT on human lung adenocarcinoma A549 cells were examined at both the cellular and the protein level. Cytotoxicity and genotoxicity were examined, followed by a proteomic analysis (2-DE coupled with LC-MS/MS) of the cellular response to MWCNT. Our results demonstrate that MWCNT induces cytotoxicity in A549 cells only at relatively high concentrations and longer exposure time. Within a relatively low dosage range (30 µg/ml) and short time period (24 h), MWCNT treatment does not induce significant cytotoxicity, cell cycle changes, apoptosis, or DNA damage. However, at these low doses and times, MWCNT treatment causes significant changes in protein expression. A total of 106 proteins show altered expression at various time points and dosages, and of these, 52 proteins were further identified by MS. Identified proteins are involved in several cellular processes including proliferation, stress, and cellular skeleton organization. In particular, MWCNT treatment causes increases in actin expression. This increase has the potential to contribute to increased migration capacity and may be mediated by reactive oxygen species (ROS).  相似文献   
69.
It is difficult to construct a control group for trials of adjuvant therapy (Rx) of prostate cancer after radical prostatectomy (RP) due to ethical issues and patient acceptance. We utilized 8 curve-fitting models to estimate the time to 60%, 65%, … 95% chance of progression free survival (PFS) based on the data derived from Kattan post-RP nomogram. The 8 models were systematically applied to a training set of 153 post-RP cases without adjuvant Rx to develop 8 subsets of cases (reference case sets) whose observed PFS times were most accurately predicted by each model. To prepare a virtual control group for a single-arm adjuvant Rx trial, we first select the optimal model for the trial cases based on the minimum weighted Euclidean distance between the trial case set and the reference case set in terms of clinical features, and then compare the virtual PFS times calculated by the optimum model with the observed PFSs of the trial cases by the logrank test. The method was validated using an independent dataset of 155 post-RP patients without adjuvant Rx. We then applied the method to patients on a Phase II trial of adjuvant chemo-hormonal Rx post RP, which indicated that the adjuvant Rx is highly effective in prolonging PFS after RP in patients at high risk for prostate cancer recurrence. The method can accurately generate control groups for single-arm, post-RP adjuvant Rx trials for prostate cancer, facilitating development of new therapeutic strategies.  相似文献   
70.
Marine algae of the genus Nannochloropsis are promising producers of biofuel precursors and nutraceuticals and are also harvested commercially for aquaculture feed. We have used quick-freeze, deep-etch electron microscopy, Fourier transform infrared spectroscopy, and carbohydrate analyses to characterize the architecture of the Nannochloropsis gaditana (strain CCMP 526) cell wall, whose recalcitrance presents a significant barrier to biocommodity extraction. The data indicate a bilayer structure consisting of a cellulosic inner wall (∼75% of the mass balance) protected by an outer hydrophobic algaenan layer. Cellulase treatment of walls purified after cell lysis generates highly enriched algaenan preparations without using the harsh chemical treatments typically used in algaenan isolation and characterization. Nannochloropsis algaenan was determined to comprise long, straight-chain, saturated aliphatics with ether cross-links, which closely resembles the cutan of vascular plants. Chemical identification of >85% of the isolated cell wall mass is detailed, and genome analysis is used to identify candidate biosynthetic enzymes.  相似文献   
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