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Jee Hyun Kim Byung Chul Jee Jang Mi Lee Chang Suk Suh Seok Hyun Kim 《Yonsei medical journal》2014,55(5):1333-1340
Purpose
The aim of this work was to evaluate nuclear histone acetylation level and total histone acetyltransferase (HAT) and deacetylase (HDAC) activity in ejaculated sperm and their relevance to conventional sperm parameters.Materials and Methods
Thirty-three normozoospermic men were included in this study. Semen samples were processed by swim-up and then immunostained by six acetylation antibodies (H3K9ac, H3K14ac, H4K5ac, H4K8ac, H4K12ac, and H4K16ac). Our preliminary study verified the expression of HAT/HDAC1 in mature human sperm. From vitrified-warmed sperm samples, total HAT/HDAC activity was measured by commercially available kits. Nuclear DNA integrity was also measured by TUNEL assay.Results
The levels of six acetylation marks were not related with conventional sperm parameters including sperm DNA fragmentation index (DFI) as well as HAT/HDAC activity. However, sperm DFI was positively correlated with HAT activity (r=0.038 after adjustment, p<0.02). HAT activity showed a negative relationship with HDAC activity (r=-0.51, p<0.01). Strict morphology was negatively correlated with acetylation enzyme index (=HAT activity/HDAC activity) (r=-0.53, p<0.01).Conclusion
Our works demonstrated a significant relationship of acetylation-associated enzyme activity and strict morphology or sperm DFI. 相似文献94.
So Jin Bing Min Ju Kim Ginnae Ahn Jaehak Im Dae Seung Kim Danbee Ha Jinhee Cho Areum Kim Youngheun Jee 《Acta histochemica》2014
Owing to its susceptibility to radiation, the small intestine of mice is valuable for studying radioprotective effects. When exposed to radiation, intestinal crypt cells immediately go through apoptosis, which impairs swift differentiation necessary for the regeneration of intestinal villi. Our previous studies have elucidated that acidic polysaccharide of Panax ginseng (APG) protects the mouse small intestine from radiation-induced damage by lengthening villi with proliferation and repopulation of crypt cells. In the present study, we identified the molecular mechanism involved. C57BL/6 mice were irradiated with gamma-rays with or without APG and the expression levels of apoptosis-related molecules in the jejunum were investigated using immunohistochemistry. APG pretreatment strongly decreased the radiation-induced apoptosis in the jejunum. It increased the expression levels of anti-apoptotic proteins (Bcl-2 and Bcl-XS/L) and dramatically reduced the expression levels of pro-apoptotic proteins (p53, BAX, cytochrome c and caspase-3). Therefore, APG attenuated the apoptosis through the intrinsic pathway, which is controlled by p53 and Bcl-2 family members. Results presented in this study suggest that APG protects the mouse small intestine from irradiation-induced apoptosis through inhibition of the p53-dependent pathway and the mitochondria/caspase pathway. Thus, APG may be a potential agent for preventing radiation induced injuries in intestinal cells during radio-therapy such as in cancer treatment. 相似文献
95.
Jeong-Ok Lee Ju Hyun Lee Soyeon Ahn Jin Won Kim Hyun Chang Yu Jung Kim Keun-Wook Lee Jee Hyun Kim Soo-Mee Bang Jong Seok Lee 《Journal of Korean medical science》2014,29(2):224-229
This study assessed the prevalence of, and risk factors for, iron deficiency (ID) and iron deficiency anemia (IDA) among participants of the fifth Korean Health and Nutrition Examination Survey, 2010. Of 8,958 participants, 6,758 individuals ≥10 yr had sufficient data for the analysis of anemia and iron status. ID was defined as a transferrin saturation <10% or serum ferritin <15 µg/L. The prevalence of ID and IDA was 2.0% (95% confidence interval [CI], 1.3%-2.6%) and 0.7% (95% CI, 0.3%-1.0%), respectively, in males, and 22.4% (95% CI, 20.7%-24.2%) and 8.0% (95% CI, 6.8%-9.2%), respectively, in females. In reproductive age females, the prevalence of ID and IDA was 31.4% (95% CI, 28.9%-33.8%) and 11.5% (95% CI, 9.6%-13.4%), respectively. Compared to the prevalence of IDA in adult males 18-49 yr, the relative risks of IDA in adults ≥65 yr, lactating females, premenopausal females, and pregnant females were 8.1, 35.7, 42.8, and 95.5, respectively. Low income, underweight, iron- or vitamin C-poor diets were also associated with IDA. For populations with defined risk factors in terms of age, gender, physiological state and socioeconomic and nutritional status, national health policy to reduce IDA is needed.
Graphical Abstract
相似文献96.
Jee Hyun Kim Jung Ryeol Lee Hye Jin Chang Byung Chul Jee Chang Suk Suh Seok Hyun Kim 《Journal of Korean medical science》2014,29(9):1266-1270
This prospective study investigated the relationship between anti-Müllerian hormone (AMH) level in the follicular fluid (FF) and the quality of the oocyte and embryo. A total of 65 FF samples from 54 women were included in this study. FF was collected from the largest preovulatory follicle sized≥20 mm of mean diameter from each ovary. Samples were divided into 3 groups according to the FF AMH levels: below the 33th percentile (low group, FF AMH<2.1 ng/mL, n=21), between the 33th and the 67th percentile (intermediate group, FF AMH=2.1-3.6 ng/mL, n=22), and above the 67th percentile (high group, FF AMH>3.6 ng/mL, n=22). The quality of the ensuing oocytes and embryos was evaluated by fertilization rate and embryo score. FF AMH levels correlated positively with the matched embryo score on day 3 after fertilization (r=0.331, P=0.015). The normal fertilization rate was significantly lower in the low group than in the intermediate group (61.9% vs. 95.5% vs. 77.3%, respectively, P=0.028). Our results suggest that the FF AMH level could be a predictor of the ensuing oocyte and embryo quality.
Graphical Abstract
相似文献97.
4D printed objects are indexed under additive manufacturing (AM) objects. The 4D printed materials are stimulus-responsive and have shape-changing features. However, the manufacturing of such objects is still a challenging task. For this, the designing space has to be explored in the initial stages, which is lagging so far. This paper encompasses two recent approaches to explore the conceptual design of 4D printed objects in detail: (a) an application-based modeling and simulation approach for phytomimetic structures and (b) a voxel-based modeling and simulation approach. The voxel-based modeling and simulation approach has the enhanced features for the rapid testing (prior to moving into design procedures) of the given distribution of such 4D printed smart materials (SMs) while checking for behaviors, particularly when these intelligent materials are exposed to a stimulus. The voxel-based modeling and simulation approach is further modified using bi-exponential expressions to encode the time-dependent behavior of the bio-inspired 4D printed materials. The shape-changing materials are inspired from biological objects, such as flowers, which are temperature-sensitive or touch-sensitive, and can be 4D printed in such a way that they are encrypted with a decentralized, anisotropic enlargement feature under a restrained alignment of cellulose fibers as in the case of composite hydrogels. Such plant-inspired architectures can change shapes when immersed in water. This paper also outlines a review of the 4D printing of (a) smart photocurable and biocompatible scaffolds with renewable plant oils, which can be a better alternative to traditional polyethylene glycol diacrylate (PEGDA) to support human bone marrow mesenchymal stem cells (hMSCs), and (b) a biomimetic dual shape-changing tube having applications in biomedical engineering as a bioimplant. The future applications would be based on these smart and intelligent materials; thus, it is important to modify the existing voxel-based modeling and simulation approach and discuss efficient printing methods to fabricate such bio-inspired materials.4D printed objects are indexed under additive manufacturing (AM) objects. 相似文献
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Min Jung Koh Hei-Cheul Jeung Kee Namkoong Hyun Cheol Chung Jee In Kang 《Journal of psychosomatic research》2014