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971.
The global invasion of Tephritidae (fruit flies) attracts a great deal of attention in the field of plant quarantine and invasion biology because of their economic importance. Predicting which one in hundreds of potential invasive fruit fly species is most likely to establish in a region presents a significant challenge, but can be facilitated using a self organising map (SOM), which is able to analyse species associations to rank large numbers of species simultaneously with an index of establishment. A global presence/absence dataset including 180 economically significant fruit fly species in 118 countries was analysed using a SOM. We compare and contrast ranked lists from six countries selected from each continent, and also show that those countries geographically close were clustered together by the SOM analysis because they have similar fruit fly assemblages. These closely clustered countries therefore represent greater threats to each other as sources of invasive fruit fly species. Finally, we indicate how this SOM method could be utilized as an initial screen to support prioritizing fruit fly species for further research into their potential to invade a region. 相似文献
972.
Lai Wang Mingjie Yang Ana Arias Lei Song Fuqiang Li Fang Tian Minghui Qin Ada Yukht Ian K. Williamson Prediman K. Shah Behrooz G. Sharifi 《PloS one》2015,10(6)
Extramedullary hematopoiesis has been shown to contribute to the pathogenesis of a variety of diseases including cardiovascular diseases. In this process, the spleen is seeded with mobilized bone marrow cells that augment its hematopoietic ability. It is unclear whether these immigrant cells that are produced/reprogrammed in spleen are similar or different from those found in the bone marrow. To begin to understand this, we investigated the relative potency of adult splenocytes per se to repopulate bone marrow of lethally-irradiated mice and its functional consequences in atherosclerosis. The splenocytes were harvested from GFP donor mice and transplanted into myeloablated wild type recipient mice without the inclusion of any bone marrow helper cells. We found that adult splenocytes repopulated bone marrow of myeloablated mice and the transplanted cells differentiated into a full repertoire of myeloid cell lineages. The level of monocytes/macrophages in the bone marrow of recipient mice was dependent on the cell origin, i.e., the donor splenocytes gave rise to significantly more monocytes/macrophages than the donor bone marrow cells. This occurred despite a significantly lower number of hematopoietic stem cells being present in the donor splenocytes when compared with donor bone marrow cells. Atherosclerosis studies revealed that donor splenocytes displayed a similar level of atherogenic and atheroprotective activities to those of donor bone marrow cells. Cell culture studies showed that the phenotype of macrophages derived from spleen is different from those of bone marrow. Together, these results demonstrate that splenocytes can seed bone marrow of myeloablated mice and modulate atherosclerosis. In addition, our study shows the potential of splenocytes for therapeutic interventions in inflammatory disease. 相似文献
973.
Suvi Parviainen Karoliina Autio Markus V?h?-Koskela Kilian Guse Sari Pesonen Thomas J. Rosol Fang Zhao Akseli Hemminki 《PloS one》2015,10(3)
Vaccinia virus is a large, enveloped virus of the poxvirus family. It has broad tropism and typically virus replication culminates in accumulation and lytic release of intracellular mature virus (IMV), the most abundant form of infectious virus, as well as release by budding of extracellular enveloped virus (EEV). Vaccinia viruses have been modified to replicate selectively in cancer cells and clinically tested as oncolytic agents. During preclinical screening of relevant cancer targets for a recombinant Western Reserve strain deleted for both copies of the thymidine kinase and vaccinia growth factor genes, we noticed that confluent monolayers of SCCF1 cat squamous carcinoma cells were not destroyed even after prolonged infection. Interestingly, although SCCF1 cells were not killed, they continuously secreted virus into the cell culture supernatant. To investigate this finding further, we performed detailed studies by electron microscopy. Both intracellular and secreted virions showed morphological abnormalities on ultrastructural inspection, suggesting compromised maturation and morphogenesis of vaccinia virus in SCCF1 cells. Our data suggest that SCCF1 cells produce a morphologically abnormal virus which is nevertheless infective, providing new information on the virus-host cell interactions and intracellular biology of vaccinia virus. 相似文献
974.
Tengfei Fu Manlin Cao Fang Liu Jiaan Zhu Dongmei Ye Xianxuan Feng Yiming Xu Gang Wang Yuehong Bai 《PloS one》2015,10(1)
Objective
To evaluate the diagnostic value of the Inlet-to-outlet median nerve area ratio (IOR) in patients with clinically and electrophysiologically confirmed carpal tunnel syndrome (CTS).Methods
Forty-six wrists in 46 consecutive patients with clinical and electrodiagnostic evidence of CTS and forty-four wrists in 44 healthy volunteers were examined with ultrasonography. The cross-sectional area (CSA) of the median nerve was measured at the carpal tunnel inlet (the level of scaphoid-pisiform) and outlet (the level of the hook of the hamate), and the IOR was calculated for each wrist. Ultrasonography and electrodiagnostic tests were performed under blinded conditions. Electrodiagnostic testing combined with clinical symptoms were considered to be the gold standard test. Receiver operating characteristic (ROC) curves were used to evaluate the diagnostic value between the inlet CSA and IOR.Results
The study population included 16 men and 30 women (mean age, 45.3 years; range, 18–83 years). The control population included 18 men and 26 women (mean age, 50.4 years; range, 18–79 years). The mean inlet CSA was 8.7 mm2 in healthy controls and 14.6mm2 in CTS group (P<0.001). The mean IOR in healthy volunteers (1.0) was smaller than that in patients (1.6, P<0.001). Receiver operating characteristic analysis revealed a diagnostic advantage to using the IOR rather than the inlet CSA (P<0.01). An IOR cutoff value of ≥ 1.3 would yield 93% specificity and 91% sensitivity in the diagnosis of CTS.Conclusion
The IOR of median nerve area promises to be an effective means in the diagnosis of CTS. A large-scale, randomized controlled trial is required to determine how and when this parameter will be used. 相似文献975.
Xiaoyu Yu Dandan Zhang Bisheng Shi Guangxu Ren Xiuhua Peng Zhong Fang Maya Kozlowski Xiaohui Zhou Xiaonan Zhang Min Wu Cong Wang Zhenghong Yuan 《PloS one》2015,10(4)
Hepatitis B virus (HBV) persistent infection is associated with ineffective immune response for the clearance of virus. Immunomodulators represent an important class of therapeutics, which potentially could be beneficial for the treatment of HBV infection. The particulate yeast-derived glucan (PYDG) has been shown to enhance the innate and adaptive immune responses. We therefore, assessed the efficacy of PYDG in enhancing HBV specific immune responses by employing the hydrodynamic injection-based (HDI) HBV transfection mouse model. Mice were intragatric administered PYDG daily for 9 weeks post pAAV/HBV1.2 hydrodynamic injection. PYDG treatment significantly promoted HBV DNA clearance and production of HBsAb compared to control mice. PYDG treatment resulted in recruitment of macrophages, dendritic cells (DCs) and effector T cells to the liver microenvironment, accompanied by a significantly augmented DCs maturation and HBV-specific IFN-γ and TNF-α production by T cell. In addition, enhanced production of Th1 cytokines in liver tissue interstitial fluid (TIF) was associated with PYDG administration. Live imaging showed the accumulation of PYDG in the mouse liver. Our results demonstrate that PYDG treatment significantly enhances HBV-specific Th1 immune responses, accompanied by clearance of HBV DNA, and therefore holds promise for further development of therapeutics against chronic hepatitis B. 相似文献
976.
977.
Song Xue Guo Yun Yun Jin Quan Fang Chuan Gang You Xin Gang Wang Xin Lei Hu Chun-Mao Han 《PloS one》2015,10(4)
Introduction
Deep burn wounds undergo a dynamic process known as wound progression that results in a deepening and extension of the initial burn area. The zone of stasis is more likely to develop more severe during wound progression in the presence of hypoperfusion. Hydrogen has been reported to alleviate injury triggered by ischaemia/reperfusion and burns in various organs by selectively quenching oxygen free radicals. The aim of this study was to investigate the possible protective effects of hydrogen against early burn-wound progression.Methods
Deep-burn models were established through contact with a boiled, rectangular, brass comb for 20 s. Fifty-six Sprague-Dawley rats were randomly divided into sham, burn plus saline, and burn plus hydrogen-rich saline (HS) groups with sacrifice and analysis at various time windows (6 h, 24 h, 48 h) post burn. Indexes of oxidative stress, apoptosis and autophagy were measured in each group. The zone of stasis was evaluated using immunofluorescence staining, ELISA, and Western blot to explore the underlying effects and mechanisms post burn.Results
The burn-induced increase in malondialdehyde was markedly reduced with HS, while the activities of endogenous antioxidant enzymes were significantly increased. Moreover, HS treatment attenuated increases in apoptosis and autophagy postburn in wounds, according to the TUNEL staining results and the expression analysis of Bax, Bcl-2, caspase-3, Beclin-1 and Atg-5 proteins. Additionally, HS lowered the level of myeloperoxidase and expression of TNF-α, IL-1β, and IL-6 in the zone of stasis while augmenting IL-10. The elevated levels of Akt phosphorylation and NF-κB p65 expression post burn were also downregulated by HS management.Conclusion
Hydrogen can attenuate early wound progression following deep burn injury. The beneficial effect of hydrogen was mediated by attenuating oxidative stress, which inhibited apoptosis and inflammation, and the Akt/NF-κB signalling pathway may be involved in regulating the release of inflammatory cytokines. 相似文献978.
Zhuoyang Fan Cheng Chen Xiaoying Pang Zhou Yu Yang Qi Xinyi Chen Huihui Liang Xiaoling Fang Xianyi Sha 《PloS one》2015,10(4)
Genexol-PM, produced by Samyang Company (Korea) is an excellent preparation of paclitaxel (PTX) for clinical cancer treatment. However, it cannot resolve the issue of multidrug resistance (MDR)—a significant problem in the administration of PTX to cancer patients. To increase the efficacy of Genexol-PM against MDR tumors, a mixed micelle capable of serving as a vehicle for PTX was developed, and two substances were chosen as carrier materials: 1) Polyethylene glycol–polylactic acid (PEG-PLA), the original vehicle of Genexol-PM. 2) Vitamin E-TPGS, an inhibitor of P-glycoprotein (P-gp). P-gp has been proven to be the main cause of MDR. In vitro evaluation indicated that the mixed micelle was an ideal PTX delivery system for the treatment of MDR tumors; the mixed micelle also showed a significantly better drug-loading coefficient than Genexol-PM. 相似文献
979.
Tiantian She Chuanke Zhao Junnan Feng Lixin Wang Like Qu Ke Fang Shaoqing Cai Chengchao Shou 《PloS one》2015,10(3)
Sarsaparilla, also known as Smilax Glabra Rhizome (SGR), was shown to modulate immunity, protect against liver injury, lower blood glucose and suppress cancer. However, its effects on cancer cell adhesion, migration and invasion were unclear. In the present study, we found that the supernatant of water-soluble extract from SGR (SW) could promote adhesion, inhibit migration and invasion of HepG2, MDA-MB-231 and T24 cells in vitro, as well as suppress metastasis of MDA-MB-231 cells in vivo. Results of F-actin and vinculin dual staining showed the enhanced focal adhesion in SW-treated cells. Microarray analysis indicated a repression of TGF-β1 signaling by SW treatment, which was verified by real-time RT-PCR of TGF-β1-related genes and immunoblotting of TGFBR1 protein. SW was also shown to antagonize TGF-β1-promoted cell migration. Collectively, our study revealed a new antitumor function of Sarsaparilla in counteracting invasiveness of a subset of cancer cells by inhibiting TGF-β1 signaling. 相似文献
980.
Chiu-Huang Kuo Tsung-Cheng Hsieh Chih-Hsien Wang Chu-Lin Chou Yu-Hsien Lai Yi-Ya Chen Yu-Li Lin Sheng-Teng Wu Te-Chao Fang 《PloS one》2015,10(4)