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141.
Farshad Shadanloo Mohammad Hasan Najafi Sayed Morteza Hosseini Mehdi Hajian Mohsen Forouzanfar Kamran Ghaedi Parvaneh Abedi Somaye Ostadhosseini Laleh Hosseini Morad‐Pasha Eskandari‐Nasab Mohammad Hossein Nasr Esfahani 《Molecular reproduction and development》2010,77(10):868-875
In relation to the growing recent interest in the establishment of sperm‐mediated gene transfer (SMGT) technology as a convenient and effective method for the simple production of transgenic animals, in this study the possibility of using SMGT to produce transgenic caprine embryos was investigated for the first time. Buck sperm were directly incubated with different concentrations (0–500 ng) of pcDNA/his/Lac‐Z plasmid and used for IVF or ICSI. Sperm used for ICSI were categorized into motile or live‐immotile group before being injected into oocytes. In a separate experiment, dead sperm prepared by repeated freezing/thawing were used for DNA‐incubation before ICSI. Sham injection was carried out by intracytoplasmic injection of approximately the same volume of media containing different doses of DNA using an ICSI needle. Transgene expression and transmission were detected by X‐Gal staining and PCR analysis of developed embryos, respectively. A reasonable blastocyst rate was observed in all the groups. Only embryos in the sham group were negative for transgene transmission. Transgene expression was completely dependent on the delivery technique and status of sperm, and was only observed in the live‐immotile and dead ICSI groups. The results of this study showed that the technique (IVF vs. ICSI vs. sham injection), sperm status (motile vs. live‐immotile vs. dead) and to some extent DNA concentration affect embryo development, transgene transmission and expression. Mol. Reprod. Dev. 77:868–875, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
142.
Canan Ersoy Ganime Sadikoglu Hasan Orhan Metin Guclu Emre Sarandol Meral Demirci Akgun Alis Ozcakir Sazi Imamoglu 《Cytokine》2010,49(3):275-278
Obesity is the presence of either abnormal absolute amount or relative proportion of body fat. Contrary to gluteal obesity, visceral obesity is associated with different metabolic alterations including insulin resistance (IR). A relatively new adipocytokine visfatin is shown to be expressed predominantly in visceral fat and exhibit insulin-mimicking effects in rodents. It is still unclear whether serum visfatin levels are associated with increased total or visceral fat mass in humans. The aim of our study was to investigate the relation between visfatin and obesity parameters namely body mass index (BMI) and waist circumference (WaC) and IR in healthy female subjects. Eighty one female subjects ?20 years of age, having no diagnosis of glucose intolerance or diabetes, hypertension and dyslipidemia were chosen. The patients were divided into four groups according to their BMI and WaC values. Serum visfatin and HOMA-IR levels did not differ among groups. No correlation was detected between serum visfatin levels and obesity and metabolic parameters. In conclusion, we demonstrated that body fat distribution did not affect serum visfatin levels in healthy female subjects. Further studies are needed to clarify the exact factors influencing and determining serum visfatin levels and its clinical reflections. 相似文献
143.
Ankita Varshney Priyankar Sen Ejaz Ahmad Mohd. Rehan Naidu Subbarao Rizwan Hasan Khan 《Chirality》2010,22(1):77-87
Human serum albumin (HSA), being the most abundant carrier protein in blood and a modern day clinical tool for drug delivery, attracts high attention among biologists. Hence, its unfolding/refolding strategies and exogenous/endogenous ligand binding preference are of immense use in therapeutics and clinical biochemistry. Among its fellow proteins albumin is known to carry almost every small molecule. Thus, it is a potential contender for being a molecular cargo/or nanovehicle for clinical, biophysical and industrial purposes. Nonetheless, its structure and function are largely regulated by various chemical and physical factors to accommodate HSA to its functional purpose. This multifunctional protein also possesses enzymatic properties which may be used to convert prodrugs to active therapeutics. This review aims to highlight current overview on the binding strategies of protein to various ligands that may be expected to lead to significant clinical applications. Chirality, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
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145.
In our previous publication we had reported the purification and characterization of Clitoria ternatea agglutinin from its seeds on fetuin CL agarose affinity column, designated CTA [A. Naeem, S. Haque, R.H. Khan. Protein J., 2007]. Since CTA binds beta-d-galactosides, this lectin can be used as valuable tool for glycobiology studies in biomedical and cancer research. So an attempt was made for a high yielding alternative purification method employing the use of asialofetuin CL agarose column for the above-mentioned lectin, designated CTL. The fetuin affinity purified agglutinin was found similar to asialofetuin affinity purified lectin in SDS pattern, HPLC and N-terminal sequence. The content of lectin was found to be 30mg/30g dry weight of pulse. The yield was 2.8% as compared to 0.3% obtained on fetuin column. The number of tryptophan and tyrosine estimated was four and six per subunit. 相似文献
146.
One hundred sixty-four adult male volunteers (29 controls [Group 1] and 135 combi drivers) enrolled in the study. The combi
drivers were divided into three groups as nonusers of either Maras powder or cigarette (Group 2), smokers (Group 3), and users of Maras powder (Group 4). Blood lead levels (BLLs) were analyzed by
atomic absorption spectrophotometer. BLL was detected as 2.8 ± 2.3 μg/dL in Group 1 (n = 29); however, it was 3.5 ± 1.6 μg/dL in Group 2 (n = 33), 3.8 ± 2.4 μg/dL in Group 3 (n = 62), and 3.9 ± 2.4 μg/dL in Group 4 (n = 40). BLL in Group 1 was found significantly lower than other groups (p < 0.05). The use of cigarette or Maras powder by the drivers did not give rise to a marked difference on the BLLs (p > 0.05). BLL of (combi) drivers was detected to be significantly higher than nondrivers; however, it was still under the
hazardous level of 10 μg/dL announced by WHO. Although there are publications reporting that usage of tobacco increases the
level of lead in blood, both smoking and use of Maras powder did not affect BLL markedly in our study.
Poster presented (the abstract section published in Congress Book) at the 7th Congress of Turkish Family Physicians, 23–26
May 2006, Cesme-IZMIR, Turkey. 相似文献
147.
148.
Kennedy AR Pissios P Otu H Roberson R Xue B Asakura K Furukawa N Marino FE Liu FF Kahn BB Libermann TA Maratos-Flier E 《American journal of physiology. Endocrinology and metabolism》2007,292(6):E1724-E1739
Ketogenic diets have been used as an approach to weight loss on the basis of the theoretical advantage of a low-carbohydrate, high-fat diet. To evaluate the physiological and metabolic effects of such diets on weight we studied mice consuming a very-low-carbohydrate, ketogenic diet (KD). This diet had profound effects on energy balance and gene expression. C57BL/6 mice animals were fed one of four diets: KD; a commonly used obesogenic high-fat, high-sucrose diet (HF); 66% caloric restriction (CR); and control chow (C). Mice on KD ate the same calories as mice on C and HF, but weight dropped and stabilized at 85% initial weight, similar to CR. This was consistent with increased energy expenditure seen in animals fed KD vs. those on C and CR. Microarray analysis of liver showed a unique pattern of gene expression in KD, with increased expression of genes in fatty acid oxidation pathways and reduction in lipid synthesis pathways. Animals made obese on HF and transitioned to KD lost all excess body weight, improved glucose tolerance, and increased energy expenditure. Analysis of key genes showed similar changes as those seen in lean animals placed directly on KD. Additionally, AMP kinase activity was increased, with a corresponding decrease in ACC activity. These data indicate that KD induces a unique metabolic state congruous with weight loss. 相似文献
149.
TLR9 expression and function is abolished by the cervical cancer-associated human papillomavirus type 16 总被引:4,自引:0,他引:4
150.
Tea polyphenols for health promotion 总被引:18,自引:0,他引:18
People have been consuming brewed tea from the leaves of the Camellia sinensis plant for almost 50 centuries. Although health benefits have been attributed to tea, especially green tea consumption since the beginning of its history, scientific investigations of this beverage and its constituents have been underway for less than three decades. Currently, tea, in the form of green or black tea, next to water, is the most widely consumed beverage in the world. In vitro and animal studies provide strong evidence that polyphenols derived from tea may possess the bioactivity to affect the pathogenesis of several chronic diseases. Among all tea polyphenols, epigallocatechin-3-gallate has been shown to be responsible for much of the health promoting ability of green tea. Tea and tea preparations have been shown to inhibit tumorigenesis in a variety of animal models of carcinogenesis. However, with increasing interest in the health promoting properties of tea and a significant rise in scientific investigation, this review covers recent findings on the medicinal properties and health benefits of tea with special reference to cancer and cardiovascular diseases. 相似文献