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201.
Virus transmission can occur either by a cell-free mode through the extracellular space or by cell-to-cell transmission involving direct cell-to-cell contact. The factors that determine whether a virus spreads by either pathway are poorly understood. Here, we assessed the relative contribution of cell-free and cell-to-cell transmission to the spreading of the human immunodeficiency virus (HIV). We demonstrate that HIV can spread by a cell-free pathway if all the steps of the viral replication cycle are efficiently supported in highly permissive cells. However, when the cell-free path was systematically hindered at various steps, HIV transmission became contact-dependent. Cell-to-cell transmission overcame barriers introduced in the donor cell at the level of gene expression and surface retention by the restriction factor tetherin. Moreover, neutralizing antibodies that efficiently inhibit cell-free HIV were less effective against cell-to-cell transmitted virus. HIV cell-to-cell transmission also efficiently infected target T cells that were relatively poorly susceptible to cell-free HIV. Importantly, we demonstrate that the donor and target cell types influence critically the extent by which cell-to-cell transmission can overcome each barrier. Mechanistically, cell-to-cell transmission promoted HIV spread to more cells and infected target cells with a higher proviral content than observed for cell-free virus. Our data demonstrate that the frequently observed contact-dependent spread of HIV is the result of specific features in donor and target cell types, thus offering an explanation for conflicting reports on the extent of cell-to-cell transmission of HIV.  相似文献   
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Monitoring intraocular pressure (IOP) is essential for pediatric cataract treatment but always difficult due to lack of cooperation in young children. We present the baseline characteristics and the first-year results of a long-term prospective cohort study, which are aimed to determine the relationship of the incidence of ocular hypertension (OH) in children after cataract surgery during the first-year period and the risk of developing late-onset glaucoma. Children were included with the following criteria: they were≤10 years old and scheduled to undergo cataract surgery with/without intraocular lens implantation; they were compliant with our follow-up protocol, which included monitoring IOP using a Tono-Pen under sedation or anesthesia. Incidence of OH, peak OH value, OH onset time and OH duration within a 12-month period following surgery were measured. In brief, 206 patients (379 eyes) were included and OH developed in 66 of 379 (17.4%) eyes. The mean follow-up period was 14.0±3.2 months (median, 12 months; range, 10–16 months). Moreover, 33 of 196 (16.8%) aphakic eyes and 33 of 183 (18.0%) IOL eyes were diagnosed with OH. The peak OH onset times were at 1-week (34/66, 51.5%) and 1-month (14/66, 21.2%) appointments postsurgery. The peak IOP value in the OH eyes was 29.9±7.5 mmHg (median, 29 mmHg; range, 21–48 mmHg). The duration of OH was 30.9±31.2 days (median, 30 days; range, 3–150 days). OH recurred in 13 eyes with a history of OH diagnosed within 1 month postsurgery (13/54, 24.1%), which needed temporary or long term use of antiglaucoma medications. In conclusion, the incidence of OH in children after cataract surgery was 17.4% during the first-year period. Children who have suffered elevated IOP in the first year after cataract surgery should be followed closely to determine if there is an increased risk of developing late-onset glaucoma.  相似文献   
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Breast cancers are heterogeneous and complex diseases, and subtypes of breast cancers may involve unique molecular mechanisms. The p16INK4a and p53 pathways are two of the major pathways involved in control of the cell cycle. They also play key roles in tumorigenesis. However, whether the roles of these pathways differ in the subtypes of breast cancer is unclear. Therefore, p16 and p53 expression were investigated in different breast cancer subtypes to ascertain their contributions to these cancers. A total of 400 cases of non-invasive ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC), including the major molecular subtypes luminal-A, luminal-B, Her-2, and triple-negative subtypes, and 50 cases of normal controls were compared. Luminal-A cancers expressed the lowest level of p16 among the subtypes in DCIS, and the level of p16 expression was up-regulated in the luminal-A of IDC (P<0.008). Triple-negative breast cancers were characterized by a correlation of p53 overexpression with a high level of p16 expression. Luminal lesion types with high p16 expression in DCIS were found to be more likely to develop into aggressive breast cancers, possibly promoted by p53 dysfunction. Taken together, the present study suggest that p16 expression in luminal-A breast cancers is associated with their progression from DCIS to IDC, and both p53 and p16 expressions are important for the development of triple-negative breast cancers in DCIS and IDC.  相似文献   
206.
Although the function and regulation of SnRK1 have been studied in various plants, its molecular mechanisms in response to abiotic stresses are still elusive. In this work, we identified an AP2/ERF domain-containing protein (designated GsERF7) interacting with GsSnRK1 from a wild soybean cDNA library. GsERF7 gene expressed dominantly in wild soybean roots and was responsive to ethylene, salt, and alkaline. GsERF7 bound GCC cis-acting element and could be phosphorylated on S36 by GsSnRK1. GsERF7 phosphorylation facilitated its translocation from cytoplasm to nucleus and enhanced its transactivation activity. When coexpressed in the hairy roots of soybean seedlings, GsSnRK1(wt) and GsERF7(wt) promoted plants to generate higher tolerance to salt and alkaline stresses than their mutated species, suggesting that GsSnRK1 may function as a biochemical and genetic upstream kinase of GsERF7 to regulate plant adaptation to environmental stresses. Furthermore, the altered expression patterns of representative abiotic stress-responsive and hormone-synthetic genes were determined in transgenic soybean hairy roots after stress treatments. These results will aid our understanding of molecular mechanism of how SnRK1 kinase plays a cardinal role in regulating plant stress resistances through activating the biological functions of downstream factors.  相似文献   
207.
Plant Cell, Tissue and Organ Culture (PCTOC) - Tree peony (Paeonia sect. Moutan) is a world famous ornamental and economically important species, but it is recalcitrant to in vitro regeneration....  相似文献   
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209.
In this study, we purpose to investigate a novel five-gene signature for predicting the prognosis of patients with laryngeal cancer. The laryngeal cancer datasets were obtained from The Cancer Genome Atlas (TCGA). Both univariate and multivariate Cox regression analysis was applied to screening for prognostic differential expressed genes (DEGs), and a novel gene signature was obtained. The performance of this Cox regression model was tested by receiver operating characteristic (ROC) curves and area under the curve (AUC). Further survival analysis for each of the five genes was carried out through the Kaplan-Meier curve and Log-rank test. Totally, 622 DEGs were screened from the TCGA datasets in this study. We construct a five-gene signature through Cox survival analysis. Patients were divided into low- and high-risk groups depending on the median risk score, and a significant difference of the 5-year overall survival was found between these two groups (P < .05). ROC curves verified that this five-gene signature had good performance to predict the prognosis of laryngeal cancer (AUC = 0.862, P < .05). In conclusion, the five-gene signature consist of EMP1, HOXB9, DPY19L2P1, MMP1, and KLHDC7B might be applied as an independent prognosis predictor of laryngeal cancer.  相似文献   
210.
Accepted as a malignant tumor worldwide, cervical cancer (CC) has attracted much attention for its high incidence and mortality rates. Previous studies have elucidated the critical regulatory function that long noncoding RNAs (lncRNAs) exert on the tumorigenesis and progression of diverse tumors. Although multiple investigations have depicted that LINC00958 has a great impact on the complex biological process of many cancers, knowledge concerning the regulatory role of LINC00958 in CC remains limited and needs to be further explored. In our study, LINC00958 expression was evidently overexpressed in CC tissues and cells. Besides this, LINC00958 negatively regulated miR-625-5p expression and was verified to bind with miR-625-5p in CC. Subsequently, it was testified by a series of experiments that LINC00958 promotes CC cell proliferation and metastasis by sponging miR-625-5p. Furthermore, the leucine-rich repeat containing the eight family member E (LRRC8E) could bind with miR-625-5p, and its expression was negatively modulated by miR-625-5p, whereas positively regulated by LINC00958 in CC. Final rescue assays verified the effects of LINC0095/LRRC8E interaction and miR-625-5p/LRRC8E interaction on CC cell proliferation and metastasis. Collectively, LINC00958 facilitates CC cell proliferation and metastasis via the miR-625-5p/LRRC8E axis.  相似文献   
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