2,730 research outputs found
Production of Transgenic Cloned Miniature Pigs with Membrane-bound Human Fas Ligand (FasL) by Somatic Cell Nuclear Transfer
Cell-mediated xenograft rejection, including NK cells and CD8+ CTL, is a major obstacle in successful pig-to-human xenotransplantation. Human CD8+ CTL and NK cells display high cytotoxicity for pig cells, mediated at least in part by the Fas/FasL pathway. To prevent cell-mediated xenocytotoxicity, a membrane-bound form of human FasL (mFasL) was generated as an inhibitor for CTL and NK cell cytotoxicity that could not be cleaved by metalloproteinase to produce putative soluble FasL. We produced two healthy transgenic pigs harboring the mFasL gene via somatic cell nuclear transfer (SCNT). In a cytotoxicity assay using transgenic clonal cell lines and transgenic pig ear cells, the rate of CD8+ CTL-mediated cytotoxicity was significantly reduced in transgenic pig's ear cells compared with that in normal minipig fetal fibroblasts. Our data indicate that grafts of transgenic pigs expressing membrane-bound human FasL control the cellular immune response to xenografts, creating a window of opportunity to facilitate xenograft survival
Prevalence and correlates of sexual and gender-based violence against Chinese adolescent women who are involved in commercial sex: a cross-sectional study
Objectives: Despite the vast quantity of research among Chinese female sex workers (FSWs) to address concerns regarding HIV/sexually transmitted infection (STI) risk, there is a paucity of research on issues of sexual and gender-based violence (SGBV) and the missed opportunity for sexual and reproductive health (SRH) promotion among young FSWs. Our research aimed to assess the prevalence and correlates of SGBV among Chinese adolescent FSWs, and to explore SRH service utilisation. Design and methods: A cross-sectional study using a one-stage cluster sampling method was employed. A semistructured questionnaire was administered by trained peer educators or health workers. Multivariable logistic regression was conducted to determine individual and structural correlates of SGBV. Setting and participants: Between July and September 2012, 310 adolescent women aged 15–20 years, and who self-reported having received money or gifts in exchange for sex in the past 6 months were recruited and completed their interview in Kunming, Yunnan Province, China. Results: Findings confirm the high prevalence of SGBV against adolescent FSWs in China, with 38% (118/310) of participants affected in the past year. Moreover, our study demonstrated the low uptake of public health services and high rates of prior unwanted pregnancy (52%; 61/118), abortion (53%; 63/118) and self-reported STI symptoms (84%; 99/118) in participants who were exposed to SGBV. Forced sexual debut was reported by nearly a quarter of FSWs (23%; 70/310) and was independently associated with having had a drug-using intimate partner and younger age (\u3c17 years old) at first abortion. When controlling for potential confounders, having experienced SGBV was associated with frequent alcohol use, having self-reported symptoms of STI, having an intimate partner and having an intimate partner with illicit drug use. Conclusions: This study calls for effective and integrated interventions addressing adolescent FSWs\u27 vulnerability to SGBV and broader SRH consequences
The Application of Stereo Anti-eccentrically Teaching Methods in Traditional Chinese Qigong Course
目的 探讨立体带功防偏模式在中医气功教学中的应用。方法 从气功偏差的严重后果及目前的教学现状、立体带功防偏气功教学法的目标和意义、立体带功防偏气功教学法的具体步骤等方面进行了详细的介绍。结果 2012-2013年医学气功学课程11个班级723个学生中,出现不适感的人数仅占1.8%,在一周内不适感消失的占61.5%,两周内不适感消失者达100%,没有一例严重偏差的出现,达到了安全教学的目的。结论 立体带功防偏气功教学法可以及时发现学生出现偏差的苗头并及时纠正,提高了教学的安全性,因此值得推广。Objective: To explore the use of stereo anti-eccentrically Chinese qigong teaching mode. Method: To introduce the concrete steps of Qigong teaching methods from Qigong serious consequences,deeviation and the present teaching situation, the goal and significance of stereo anti-eccentrically qigong teaching methods etc. Result: In 2013, 6 classes and 498 students, only 23(4.61%)students appeared discomfort. Within a week the improvement of discomfort students is 16(69.56%),disappearance of discomfort students is 5(21.73%), two weeks later,disappeared discomfort students achieve 100%, have no emergence of severe deviation, reached the safety of teaching purpose. Conclusion: Stereo anti-eccentrically Qigong teaching method can find the first hint of deviation and correct them in time, can improve the security of teaching. so it is worth spreading
Isolation of nematicidal constituents from essential oil of Kaempferia galanga L rhizome and their activity against Heterodera avenae Wollenweber
Purpose: To explore the nematicidal activities of the essential oil of Kaempferia galanga rhizomes and its isolated constituents against Heterodera avenae.Methods: Essential oil of K. galanga rhizomes was obtained by hydrodistillation and characterized by gas chromatography/mass spectrometric (GC/MS) analysis using HP-5MS column. Evaluation of nematicidal toxicity was performed against juveniles (J2) of H. avenae. The bioactive constituent compounds were isolated and identified from the oil based on bioactivity-directed fractionation.Results: Forty-one components were identified and the main components of the essential oil of K. galanga are as follows: ethyl-ρ-methoxy cinnamate (34.79 %), ethyl cinnamate (20.72%), 1,8-cineole (8.96 %), trans-cinnamaldehyde (7.03%) and borneol (5.64 %). The essential oil exhibited nematicidal activity against the cereal cyst nematode with an LC50 value of 91.78 μg/mL. Ethyl cinnamate, ethyl ρ-methoxy cinnamate and trans-cinnamaldehyde (median lethal concentration LC50 = 100.60 μg/ml, 83.04 μg/mL and 94.75 μg/mL, respectively) exhibited stronger nematicidal toxicity than borneol (LC50 = 734.89 μg/mL) and 1,8-cineole (LC50 = 921.21 μg/mL) against the cereal cyst nematode.Conclusion: The results indicate that the essential oil of K. galanga and its isolated constituents have a potential for development into natural nematicides for the control of cereal cyst nematodes.Keywords: Kaempferia galanga, Heterodera avenae, Nematicidal activity, Cereal cyst nematodes, Ethyl cinnamate, Ethyl ρ-methoxy cinnamate, Trans-cinnamaldehyd
Terretonin, ophiobolin, and drimane terpenes with absolute configurations from an algicolous Aspergillus ustus
One new meroterpene, 1,2-dihydroterretonin F (2), five new sesterterpenes, (6a)-21-deoxyophiobolin G(3), (6a)-16,17-dihydro-21-deoxyophiobolin G (4), phiobolin U (5), ophiobolin V (6), and ophiobolin W (7),two new sesquiterpenes, (6-strobilactone-B) esters of (E,E)-6,7-epoxy-2,4-octadienoic acids (13 and 14),and twelve known terpenes (1, 8–12, and 15–20) were isolated from Aspergillus ustus, a fungus from the fresh tissue of marine green alga Codium fragile. Their structures and absolute configurations were identified by NMR and mass spectroscopic methods as well as quantum chemical calculations. Some of the isolates exhibited antibacterial activity and brine shrimp toxicity.One new meroterpene, 1,2-dihydroterretonin F (2), five new sesterterpenes, (6 alpha)-21-deoxyophiobolin G (3), (6 alpha)-16,17-dihydro-21-deoxyophiobolin G (4), ophiobolin U (5), ophiobolin V (6), and ophiobolin W(7), two new sesquiterpenes, (6-strobilactone-B) esters of (E,E)-6,7-epoxy-2,4-octadienoic acids (13 and 14), and twelve known terpenes (1, 8-12, and 15-20) were isolated from Aspergillus ustus, a fungus from the fresh tissue of marine green alga Codium fragile. Their structures and absolute configurations were identified by NMR and mass spectroscopic methods as well as quantum chemical calculations. Some of the isolates exhibited antibacterial activity and brine shrimp toxicity
Dietary Lipoic Acid Influences Antioxidant Capability and Oxidative Status of Broilers
The effects of lipoic acid (LA) on the antioxidant status of broilers were investigated. Birds (1 day old) were randomly assigned to four groups and fed corn-soybean diets supplemented with 0, 100, 200, 300 mg/kg LA, respectively. The feeding program included a starter diet from 1 to 21 days of age and a grower diet from 22 to 42 days of age. Serum, liver and muscle samples were collected at 42 days of age. For antioxidant enzymes, superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity in serum, liver and breast muscle significantly increased in chickens fed with LA. The concentration of malondiadehyde (MDA), an indicator of lipid peroxidation, was significantly lower in serum, liver and leg muscle in birds that received LA than in the control group. Treatments with LA significantly increased glutathione (GSH) content in liver and increased α-tocopherol content in leg muscle as compared to the control. These results indicate that dietary supplementation with 300 mg/kg LA may enhance antioxidant capability and depress oxidative stress in broilers
An Exposure Meter of Lijiang Fiber-fed High-Resolution Spectrograph
In 2016, an exposure meter was installed on the Lijiang Fiber-fed
High-Resolution Spectrograph to monitor the coupling of starlight to the
science fiber during observations. Based on it, we investigated a method to
estimate the exposure flux of the CCD in real time by using the counts of the
photomultiplier tubes (PMT) of the exposure meter, and developed a piece of
software to optimize the control of the exposure time. First, by using
flat-field lamp observations, we determined that there is a linear and
proportional relationship between the total counts of the PMT and the exposure
flux of the CCD. Second, using historical observations of different spectral
types, the corresponding relational conversion factors were determined and
obtained separately. Third, the method was validated using actual observation
data, which showed that all values of the coefficient of determination were
greater than 0.92. Finally, software was developed to display the counts of the
PMT and the estimated exposure flux of the CCD in real-time during the
observation, providing a visual reference for optimizing the exposure time
control.Comment: Published in Research in Astronomy and Astrophysic
Does PGA external stenting reduce compliance mismatch in venous grafts?
BACKGROUND: Autogenous vein grafting is widely used in regular bypassing procedures. Due to its mismatch with the host artery in both mechanical property and geometry, the graft often over expands under high arterial blood pressure and forms a step-depth where eddy flow develops, thus causing restenosis, fibrous graft wall, etc. External stents, such as sheaths being used to cuff the graft, have been introduced to eliminate these mismatches and increase the patency. Although histological and immunochemical studies have shown some positive effects of the external stent, the mechanical mismatch under the protection of an external stent remains poorly analyzed. METHODS: In this study, the jugular veins taken from hypercholesterolemic rabbits were transplanted into the carotid arteries, and non-woven polyglycolic acid (PGA) fabric was used to fabricate the external stents to study the effect of the biodegradable external stent. Eight weeks after the operation, the grafts were harvested to perform mechanical tests and histological examinations. An arc tangent function was suggested to describe the relationship between pressure and cross-sectional area to analyse the compliance of the graft. RESULTS: The results from the mechanical tests indicated that grafts either with or without external stents displayed large compliance in the low-pressure range and were almost inextensible in the high-pressure range. This was very different from the behavior of the arteries or veins in vivo. The data from histological tests showed that, with external stents, collagen fibers were more compact, whilst those in the graft without protection were looser and thicker. No elastic fiber was found in either kind of grafts. Furthermore, grafts without protection were over-expanded which resulted in much bigger cross-sectional areas. CONCLUSION: The PGA external extent contributes little to the reduction of the mechanical mismatch between the graft and its host artery while remodeling develops. For the geometric mismatch, it reduces the cross-section area, therefore matching with the host artery much better. Although there are some positive effects, conclusively the PGA is not an ideal material for external stent.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are
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