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231.
Liang Kou Xiao-Wen Lu Min-Ke Wu Hang Wang Yu-Jiao Zhang Soh Sato Jie-Fei Shen 《Biochemical and biophysical research communications》2014
Dedifferentiated fat (DFAT) cells derived from mature adipocytes have been considered to be a homogeneous group of multipotent cells, which present to be an alternative source of adult stem cells for regenerative medicine. However, many aspects of the cellular nature about DFAT cells remained unclarified. This study aimed to elucidate the basic characteristics of DFAT cells underlying their functions and differentiation potentials. By modified ceiling culture technique, DFAT cells were converted from human mature adipocytes from the human buccal fat pads. Flow cytometry analysis revealed that those derived cells were a homogeneous population of CD13+ CD29+ CD105+ CD44+ CD31− CD34− CD309− α-SMA− cells. DFAT cells in this study demonstrated tissue-specific differentiation properties with strong adipogenic but much weaker osteogenic capacity. Neither did they express endothelial markers under angiogenic induction. 相似文献
232.
Xinfen Yu Tao Jin Yujun Cui Xiaoying Pu Jun Li Jin Xu Guang Liu Huijue Jia Dan Liu Shili Song Yang Yu Li Xie Renjie Huang Hua Ding Yu Kou Yinyan Zhou Yayu Wang Xun Xu Ye Yin Jian Wang Chenyi Guo Xianwei Yang Liangping Hu Xiaopeng Wu Hailong Wang Jun Liu Guoqiu Zhao Jiyong Zhou Jingcao Pan George F. Gao Ruifu Yang Jun Wang 《Journal of virology》2014,88(6):3423-3431
233.
Background and aims
Much attention has focused on the effects of tropospheric ozone (O3) on terrestrial ecosystems and plant growth. Since O3 pollution is currently an issue in China and many parts of the world, understanding the effects of elevated O3 on soil carbon (C) and nitrogen (N) sequestration is essential for efforts to predict C and N cycles in terrestrial ecosystems under predicted increases in O3. Thus the main objective of this study was to determine whether an increases in atmospheric O3 concentration influenced soil organic C (SOC) and N sequestration.Methods
A free-air O3 enrichment (O3-FACE) experiment was started in 2007 and used continuous O3 exposure from March to November each year during crop growth stage in a rice (Oryza sativa L.)—wheat (Triticum aestivum L.) rotation field in the Jiangsu Province, China. We investigated differences in SOC and N and soil aggregate composition in both elevated and ambient O3 conditions.Results
Elevated atmospheric O3 (18–80 nmol mol?1 or 50 % above the ambient) decreased the SOC and N concentration in the 0–20 cm soil layer after 5 years. Elevated O3 significantly decreased the SOC concentration by 17 % and 5.6 % in the 0–3 cm and the 10–20 cm layers, respectively. Elevated O3 significantly decreased the N concentration by 8.2–27.8 % in three layers at the 20 cm depth. In addition, elevated O3 influenced the formation and transformation of soil aggregates and the distribution of SOC and N in the aggregates across soil layer classes. Elevated O3 significantly decreased the macro-sized aggregate fraction (16.8 %) and associated C and N (0.5 g kg?1 and 0.32 g kg?1, respectively), and significantly increased the silt+ clay-sized aggregate fraction (61 %) and associated C (1.7 g kg?1) in the 0–3 cm layer. Elevated O3 significantly decreased the macro-sized aggregate fraction (9.6 %) and associated C and N (1.4 g kg?1 and 0.35 g kg?1, respectively), and significantly increased the silt+ clay-sized aggregate fraction (41.8 %) and decreased the corresponding associated N (0.14 g kg?1) in the 3–10 cm layer. Elevated O3 did not significantly effect the formation and transformation of aggregates in the 10–20 cm layer, yet it did significantly increase the C concentration in the macro-sized fraction (1 g kg?1) and decrease the N concentration in the macro- and micro-sized fractions (0.24 g kg?1 and 0.16 g kg?1, respectively).Conclusion
Long-term exposure to elevated atmospheric O3 negatively affected the physical structure of the soil and impaired soil C and N sequestration. 相似文献234.
Haizhou Liu Na Han Wei Fang James Adams Kou Zheng Tianxian Li Zhihong Hu Simon Rayner 《Virologica Sinica》2014,(2):126-127
Dear Editor,Nucleotide and protein sequences of isolates collectedfrom infected populations can be useful for determiningthe threats,such as host adaptation,which are associatedwith the emergence of new lineages.March 2013 saw thefirst reports of a new H7N9 lineage in Shanghai,Chinathat saw a gradual increase in the number of cases;but,by 17th May 2013,four Chinese provinces had ended 相似文献
235.
236.
Bo Zhou Birong Lin Jing Li Weizhu Qian Sheng Hou Dapeng Zhang Geng Kou Bohua Li Hao Wang Yongchuan Chen Yajun Guo 《MABS-AUSTIN》2012,4(1):110-119
The goal of the studies presented here was to determine the tolerability, pharmacokinetic and pharmacodynamic profiles of CMAB007, a biosimilar of omalizumab (Xolair; a humanized anti-immunoglobulin E monoclonal antibody), in healthy, male Chinese subjects. Thirty-six healthy Chinese men participated in two open-label, dose-escalation studies: 27 in a single-dose study (150, 300 or 600 mg) and 9 in a multiple-dose study (150 or 300 mg every 4 weeks for 20 weeks). The safety profiles of both studies were generally unremarkable. No drug-related adverse event was observed. CMAB007 exhibited a linear PK profile over the dose range of 150-600 mg. In the single-dose study, maximum concentration (Cmax) was reached within 6–8 d, and Cmax and area under concentration-time curve (AUC) increased linearly with the dose. In the multiple-dose study, steady-state appeared to have been achieved after the third dose. Css-max and AUCτ also showed dose-linearity. A dose-dependent suppression of free IgE was observed during treatment, as a median percentage change from baseline, 91.9–98.8%, in the three single-dose groups. No anti-CMAB007 antibodies were detected after dosing in any subject. Subcutaneous administration of CMAB007 was well-tolerated and seemed to be effective in reducing free IgE in healthy Chinese volunteers, which provides important information for further clinical studies.Key words: pharmacokinetics, pharmacodynamics, safety, IgE, humanized antibody 相似文献
237.
Pitt C Diawara H Ouédraogo DJ Diarra S Kaboré H Kouéla K Traoré A Dicko A Konaté AT Chandramohan D Diallo DA Greenwood B Conteh L 《PloS one》2012,7(3):e32900
Background
Intermittent preventive treatment of malaria in children (IPTc) is a highly efficacious method of malaria control where malaria transmission is highly seasonal. However, no studies published to date have examined community perceptions of IPTc.Methods
A qualitative study was undertaken in parallel with a double-blind, placebo-controlled, randomized trial of IPTc conducted in Mali and Burkina Faso in 2008–2009 to assess community perceptions of and recommendations for IPTc. Caregivers and community health workers (CHWs) were purposively sampled. Seventy-two in-depth individual interviews and 23 focus group discussions were conducted.Findings
Widespread perceptions of health benefits for children led to enthusiasm for the trial and for IPTc specifically. Trust in and respect for those providing the tablets and a sense of obligation to the community to participate in sanctioned activities favoured initial adoption. IPTc fits in well with existing understandings of childhood illness. Participants did not express concerns about the specific drugs used for IPTc or about providing tablets to children without symptoms of malaria. There was no evidence that IPTc was perceived as a substitute for bed net usage, nor did it inhibit care seeking. Participants recommended that distribution be “closer to the population”, but expressed concern over caregivers'' ability to administer tablets at home.Conclusions
The trial context mediated perceptions of IPTc. Nonetheless, the results indicate that community perceptions of IPTc in the settings studied were largely favourable and that the delivery strategy rather than the tablets themselves presented the main areas of concern for caregivers and CHWs. The study identifies a number of key questions to consider in planning an IPTc distribution strategy. Single-dose formulations could increase the success of IPTc implementation, as could integration of IPTc within a package of activities, such as bed net distribution and free curative care, for which demand is already high. 相似文献238.
Ru Z Xiao W Pajot A Kou Z Sun S Maillere B Zhao G Ojcius DM Lone YC Zhou Y 《PloS one》2012,7(3):e32247
A new homozygous humanized transgenic mouse strain, HLA-A2.1(+/+)HLA-DP4(+/+) hCD4(+/+)mCD4(-/-)IAβ(-/-)β2m(-/-) (HLA-A2/DP4), was obtained by crossing the previously characterized HLA-A2(+/+)β2m(-/-) (A2) mouse and our previously created HLA-DP4(+/+) hCD4(+/+)mCD4(-/-)IAβ(-/-) (DP4) mouse. We confirmed that the transgenes (HLA-A2, HLA-DP4, hCD4) inherited from the parental A2 and DP4 mice are functional in the HLA-A2/DP4 mice. After immunizing HLA-A2/DP4 mice with a hepatitis B DNA vaccine, hepatitis B virus-specific antibodies, HLA-A2-restricted and HLA-DP4-restricted responses were observed to be similar to those in naturally infected humans. Therefore, the present study demonstrated that HLA-A2/DP4 transgenic mice can faithfully mimic human cellular responses. Furthermore, we reported four new HLA-DP4-restricted epitopes derived from HBsAg that were identified in both vaccinated HLA-A2/DP4 mice and HLA-DP4-positive human individuals. The HLA-A2/DP4 mouse model is a promising preclinical animal model carrying alleles present to more than a quarter of the human population. This model should facilitate the identification of novel HLA-A2- and HLA-DP4-restricted epitopes and vaccine development as well as the characterization of HLA-DP4-restricted responses against infection in humans. 相似文献
239.
Solasodine acetate, an anticancer steroidal alkaloid, was synthesized from diosgenin in 8 steps with an overall yield of 23%. A key synthetic step involves the formation of 5/6-oxazaspiroketal moiety via hypoiodite-mediated aminyl radical cyclization of a steroidal primary amine. 相似文献
240.
YuShuang Luo XiaoXiao Kou XueZhi Ding ShengBiao Hu Ying Tang WenPing Li Fan Huang Qi Yang HanNa Chen LiQiu Xia 《中国科学:生命科学英文版》2012,55(2):172-180
To promote spinosad biosynthesis by improving the limited oxygen supply during high-density fermentation of Saccharopolyspora spinosa, the open reading frame of the Vitreoscilla hemoglobin gene was placed under the control of the promoter for the erythromycin resistance gene by splicing using overlapping
extension PCR. This was cloned into the integrating vector pSET152, yielding the Vitreoscilla hemoglobin gene expression plasmid pSET152EVHB. This was then introduced into S. spinosa SP06081 by conjugal transfer, and integrated into the chromosome by site-specific recombination at the integration site ΦC31
on pSET152EVHB. The resultant conjugant, S. spinosa S078-1101, was genetically stable. The integration was further confirmed by PCR and Southern blotting analysis. A carbon
monoxide differential spectrum assay showed that active Vitreoscilla hemoglobin was successfully expressed in S. spinosa S078-1101. Fermentation results revealed that expression of the Vitreoscilla hemoglobin gene significantly promoted spinosad biosynthesis under normal oxygen and moderately oxygen-limiting conditions
(P<0.01). These findings demonstrate that integrating expression of the Vitreoscilla hemoglobin gene improves oxygen uptake and is an effective means for the genetic improvement of S. spinosa fermentation. 相似文献