Glucose metabolism during in vitro maturation of mouse oocytes: An study using RNA interference.

In previous studies on glucose metabolism during in vitro maturation, intact cumulus-oocyte complexes (COCs) were treated with enzyme inhibitors/activators. Because inhibitors/activators may have non-specificity and/or toxicity, and culture of COCs cannot differentiate whether glucose metabolism of cumulus cells (CCs) or that of the oocyte supports oocyte maturation, results from the previous studies must be verified by silencing genes in either CCs or cumulus-denuded oocytes (DOs). In this study, RNAi was adopted to specify the effects of glucose metabolism in CCs or DOs on oocyte maturation. Although silencing either glyceraldehyde 3-phosphate dehydrogenase (GAPDH) or glucose-6-phosphate dehydrogenase (G6PD) genes in CCs significantly decreased competence of the cocultured DOs, silencing G6PD impaired competence to a greater extent. While silencing G6PD or GAPDH of CCs decreased glutathione and ATP contents of cocultured DOs to similar extents, silencing G6PD increased oxidative stress as well. Analysis on metabolite contents and oxidative stress index and culture of DOs in medium conditioned with gene-silenced CCs indicated that CCs supported oocyte maturation by releasing glucose metabolites. Silencing mitochondrial pyruvate carrier 1 or NADH dehydrogenase (ubiquintone) flavoprotein 1 of DOs significantly impaired their maturation. The results have unequivocally confirmed that CCs promote oocyte maturation by releasing glucose metabolites from both pentose phosphate pathway (PPP) and glycolysis. Pyruvate is transferred into DOs by mitochondrial pyruvate carrier (MPC) and utilized through mitochondrial electron transport to support maturation.

[Myopia prevalence and influencing factor analysis of primary and middle school students in our country].

OBJECTIVES: To explore the situation and the affect factors of myopia and scientificalness and effectiveness of eye exercises about primary and middle school students. METHODS: Through the random cluster sampling method, 20 000 students of 90 schools including key and non-key primary or junior or senior school in country and city of shandong, qinghai, yunnan, Shanghai and wenzhou were random selected. Primary students is 11 246 junior students is 3673 senior students is 4220.We surveyed related situation of eye exercises, myopia. a total of 19 139 valid questionnaires were received. By random sampling stratification method, freshmen were selected and retrospective surveyed. 929 freshmen have normal vision when they graduated primary school. 338 freshmen have normal vision when they graduated primary school.2 groups are considered analysis object, and Myopic students of the former in junior school stages and the latter in senior school stages are considered case group, normal vision are considered control group, and then through the Logistic multiple stepwise regression analysis, a regression analysis model is established. RESULTS: This survey show that myopia prevalence was 13.7% of primary students, 42.9% of junior students, 69.7% of senior students. According to the significant P < 0.001, Rsquare = 0.14, the result shows that the model has the significant statistical significance. Among the influence factors, whether to long-term excessive use eye is the most significant, and following by outdoor activities and gender. A chi-square test χ(2) = 0.371 and P = 0.543 show that doing eye exercises was not statistically significant to prevalence of myopia. CONCLUSION: The influence factors are changed, and the preventive methods should be adjusted with the social environment.

[Impact factor of timeliness lag for seeing a doctor about cataract patient in Wenzhou region of Zhejiang province].

OBJECTIVE: Investigation the impact factor of timeliness lag about cataract patient of operation. METHODS: Through Opportunistic Screening , from January 2007 to January 2012, we extracted people aged 50 or above and carried out the cataract screening in 10 towns of Wenzhou region of Zhejiang province. People extracted was checked by slit lamp microscope and ophthalmoscope directly, and the people who are suit for operation were brought to a first-rate of level three eye hospital and operated by MSICS . At the same time we have made questionnaire about five aspect including basic situation, economic status, basic life status, health and medical status and health needs for the operator and this questionnaire involves twenty-three relevant indexes about the timeliness, these factors of timeliness for patients seeing a doctor are judged. RESULTS: 36 681 people are checked for five years and 10 326 people(10 326 eyes) are suitable for surgery. Through analyzing sixteen relevant indexes about the timeliness , there are ten indexes which have Statistical Significance including in transportation, the distance for nearest medical aid post , care knowledge, population of family, income of family, respondents degree , the highest degree of family members type of work, structure of building, government subsidies. The first reason that the people can't be operated in time are economic difficulties, next are older and making children trouble for seven factors of no operation in time. The people for this three reason is more than 75% for not seeing a doctor in time. CONCLUSION: The key work of blindness prevention and treatment is the cataract surgery for our country.Eye doctors pay attention to new surgical technique , at the same time we should promote MSICS which is technique of low cost and have good effect of the operation.

[Analysis of correlative factors and prevalence on China's youth myopia].

OBJECTIVE: To understand and address our vision changes in primary and secondary students, in order to explore the prevention of juvenile myopia to provide a response and suggestions. METHODS: A random cluster sampling method, random sample of 90 rural and urban schools in Shandong, Qinghai, Yunnan, Shanghai and Wenzhou from May 2008 to September 2009, including 20 000 students (per province, 4000 x 5) from elementary school and junior high school of focus and non-focus, primary 11 246, junior high school students 3673, high school 4220, of which 11 177 were from the urban students, rural students in 7962, aged 6 to 19 years old, male to female ratio is basically the same. For myopia and related survey, a total of 19, 139 valid questionnaires were recovered. Using SPSS 13.0 software statistical analysis, different regions and different grades was used to compare the prevalence of myopia chi(2) test, using Logistic regression analysis on the major risk factors for myopia. RESULTS: The survey are as follows, the prevalence of myopia in primary was 13.7%; the prevalence of myopia in junior high was 42.9%, the prevalence of myopia in high school was 69.7%. The highest rate of myopia prevalence of primary school students in Shandong was 19.7%, the lowest was 11.9% in Qinghai, Shanghai, Wenzhou and Yunnan are similar; prevalence myopia of junior high in Wenzhou up to 50.6%, followed by Shanghai, and 47.2%, the lowest was 33.6% in Qinghai; the highest prevalence of myopia and high school students in Shandong, reaching 87.3%, followed by 72.0% in Wenzhou, and the lowest was 60.2% in Shanghai. CONCLUSION: This survey shows that the prevalence of myopia of China's primary and secondary schools in coastal was higher than areas of mainland, in developed regions was higher than in less developed regions, and the plateau region and the strong ultraviolet light similar to the plain areas. Provincial prevalence of myopia increased from primary to high school continued the same trend.

Effects of glucose metabolism pathways on nuclear and cytoplasmic maturation of pig oocytes.

The developmental competence of IVM porcine oocytes is still low compared with that in their in vivo counterparts. Although many studies reported effects of glucose metabolism (GM) on oocyte nuclear maturation, few reported on cytoplasmic maturation. Previous studies could not differentiate whether GM of cumulus cells (CCs) or that of cumulus-denuded oocytes (DOs) supported oocyte maturation. Furthermore, species differences in oocyte GM are largely unknown. Our aim was to address these issues by using enzyme activity inhibitors, RNAi gene silencing and special media that could support nuclear but not cytoplasmic maturation when GM was inhibited. The results showed that GM in CCs promoted pig oocyte maturation by releasing metabolites from both pentose phosphate pathway and glycolysis. Both pyruvate and lactate were transferred into pig DOs by monocarboxylate transporter and pyruvate was further delivered into mitochondria by mitochondrial pyruvate carrier in both pig DOs and CCs. In both pig DOs and CCs, pyruvate and lactate were utilized through mitochondrial electron transport and LDH-catalyzed oxidation to pyruvate, respectively. Pig and mouse DOs differed in their CC dependency for glucose, pyruvate and lactate utilization. While mouse DOs could not, pig DOs could use the lactate-derived pyruvate.

[The evaluation of tendency of cataract prevalence from 1987 to 2006 in Zhejiang province].

OBJECTIVE: To evaluate the long-term trend of cataract prevalence and the effect of prevention and treatment blindness in Zhejiang Province. METHODS: The data were obtained from handicapped sampling investigation in 1987 and 2006 in Zhejiang Province, and from a database of prevention and treatment blindness of the Zhejiang Province Disabled Persons' Federation. RESULTS: In 2006, a random sampling investigation were carried out on both eyes blind and the low vision in Zhejiang Province. Sample size were 95,392, the prevalence rate of blindness and low vision were 2.67% per hundred and 5.94% per hundred, respectively. The prevalence rate of cataract was 7.35% per hundred, the female was higher than the male (chi2 = 81.66, P < 0.01). Among the blind, 58.86% was caused by cataract, and the low vision caused by cataract was 63.79%. Comparing with the first disabled person' investigation in 1987, the result showed that the prevalence of blindness had reduces slightly, but no significantly difference (chi2 = 0.384, P = 0.535), and that the prevalence of low vision appeared significantly increase (chi2 = 32.434, P < 0.01). Together with two investigations results indicated that cataract is the first cause for the vision disability. CONCLUSION: Cataract is still the first cause for blindness and low vision. Though the effort to prevention and treatment blindness during 20 years obtains some certain results, prevent and treat blindness will still be an arduous work in Zhejiang province, because of accelerated aging population problem, which will induce an increase on number of cataract patient.

Effects of glucose metabolism pathways on sperm motility and oxidative status during long-term liquid storage of goat semen.

Although great efforts were made to prolong the fertility of liquid-stored semen, limited improvements have been achieved in different species. Although it is expected that energy supply and the redox potential will play an essential role in sperm function, there are few reports on the impact of specific energy substrates on spermatozoa during liquid semen storage. Furthermore, although it is accepted that glucose metabolism through glycolysis provides energy, roles of pentose phosphate pathway (PPP) and tricarboxylic acid cycle remain to be unequivocally found in spermatozoa. We have studied the pathways by which spermatozoa metabolize glucose during long-term liquid storage of goat semen. The results indicated that among the substrates tested, glucose and pyruvate were better than lactate in maintaining goat sperm motility. Although both glycolysis and PPP were essential, PPP was more important than glycolysis to maintain sperm motility. Pentose phosphate pathway reduced oxidative stress and provided glycolysis with more intermediate products such as fructose-6-phosphate. Pyruvate entered goat spermatozoa through monocarboxylate transporters and was oxidized by the tricarboxylic acid cycle and electron transfer to sustain sperm motility. Long-term liquid semen storage can be used as a good model to study sperm glucose metabolism. The data are important for an optimal control of sperm survival during semen handling and preservation not only in the goat but also in other species.

Effects of glucose metabolism during in vitro maturation on cytoplasmic maturation of mouse oocytes.

Although there are many reports on the effect of glucose metabolism on oocyte nuclear maturation, there are few studies on its effect on ooplasmic maturation. By manipulating glucose metabolism pathways using a maturation medium that could support oocyte nuclear maturation but only a limited blastocyst formation without glucose, this study determined effects of glucose metabolism pathways on ooplasmic maturation. During maturation of cumulus-oocyte-complexes (COCs) with glucose, the presence of PPP inhibitor, DHEA or glycolysis inhibitor, iodoacetate significantly decreased blastocyst rates, intraoocyte glutathione and ATP. While blastocyst rates, GSH/GSSG ratio and NADPH were higher, ROS was lower significantly in COCs matured with iodoacetate than with DHEA. Fructose-6-phosphate overcame the inhibitory effect of DHEA on PPP. During maturation of COCs with pyruvate, electron transport inhibitor, rotenone or monocarboxylate transfer inhibitor, 4-CIN significantly decreased blastocyst rates. Cumulus-denuded oocytes had a limited capacity to use glucose or lactate, but they could use pyruvate to support maturation. In conclusion, whereas glycolysis promoted ooplasmic maturation mainly by supplying energy, PPP facilitated ooplasmic maturation to a greater extent by both reducing oxidative stress and supplying energy through providing fructose-6-phosphate for glycolysis. Pyruvate was transferred by monocarboxylate transporters and utilized through mitochondrial electron transport to sustain ooplasmic maturation.

Relevant factors of estrogen changes of myopia in adolescent females.

BACKGROUND: Gender is one of the risk factors accounting for the high prevalence of adolescent myopia. Considerable research results have shown that myopia incidence of female is higher than that of male. This study aimed to analyze the correlation between ocular parameters and serum estrogen level and to investigate the vision changes along with estrogen change in menstrual cycle of adolescent females. METHODS: A total of 120 young females aged between 15 and 16 years, diagnosed with myopia were recruited. Spherical lens, cylindrical lens, axis, interpupillary distance (IPD), and vision in each tested eye of the same subject were measured by automatic optometry and comprehensive optometry, with repetition of all measurements in the menstrual cycle of the 2 nd or 3 rd days, 14 th days, and 28 th days, respectively. Serum estradiol (E 2 ) levels were assayed by chemiluminescence immunoassay at the same three times points of the menstrual cycle mentioned above. RESULTS: In young females with myopia, the spherical lens showed a statistically significant difference among all different time in menstrual cycle (all P < 0.0001). The cylindrical lens, axis, and IPD were changed significantly during the menstrual cycle (P < 0.05). The vision of the three different time points in menstrual cycle had a significant difference (χ2 = 6.35, P = 0.042). The vision during the 14 th and 28 th day was higher compared to that on the 2 nd or 3 rd days (P = 0.021). Serum E 2 levels were significantly different at different time points in menstrual cycle (P < 0.05). E 2 levels reached its maximum value on the 14 th day and the minimum value on the 2 nd or 3 rd day. CONCLUSIONS: In adolescent females, the spherical lens and other related ocular parameters vary sensitively with different levels of E 2 in menstrual cycle. Vision in late menstrual stage is significantly higher than that in premenstrual stage.

[The establishment and development of Blyth hospital in Wenzhou].

Blyth hospital was the earliest church hospital established by western missionaries in Wenzhou, since then, western medicine had been introduced into Wenzhou. The establishment and development of Blyth hospital greatly accelerated the development of Wenzhou local medical and health work so that the health level of the Wenzhou people improved. The objectives, pattern, experience and characteristics of the establishment of the hospital played a certain revelatory role in modern medical work and medical education.

Regeneration of the secondary vascular system in poplar as a novel system to investigate gene expression by a proteomic approach.

Wood formation is a complex process composing many biological events. To access its key developmental stages, we have established a regeneration system that can mimic the initiation and differentiation of cambium cells for Chinese white poplar. Anatomical studies showed that new cambium and xylem re-appeared in sequence within a few weeks after being debarked. This provides the opportunity to follow key stages of wood formation by sampling clonal trees at different regeneration times. We used this system in combination with a proteomic approach to analyze proteins expressed in different regeneration stages. PMFs for 244 proteins differentially displayed were obtained and queried against public databases. Putative functions of 199 of these proteins were assigned and classified. Regulatory genes for cell cycle progression, differentiation and cell fate were expressed in the formation of cambial tissue, while 27 genes involved in secondary wall formation were predominantly found in the xylem developing stage. This indicates that the change of gene expression pattern is corresponding to the progression of second vascular system regeneration when and where the key events of wood development occur. Further exploration of these interesting genes may provide insight into the molecular mechanisms of wood formation.