Objective To observe the morphological changes in in vitro growth of preantral follicle isolated from prepuberal mice and to assess impacts of gonadotropin (Gn), insulin transferrin selenium (ITS) and epidermal gr...Objective To observe the morphological changes in in vitro growth of preantral follicle isolated from prepuberal mice and to assess impacts of gonadotropin (Gn), insulin transferrin selenium (ITS) and epidermal growth factor (EGF) on their development. Methods Early preantral mice follicles (90-130μm diameter) were mechanical isolated and selected from 2 weeks' old mice and then cultured in alpha-minimal essential medium (α-MEM) with or without Gn, ITS and EGF. The preantral follicles were cultured singly in 20 miovliters droplets for up to 14 d. The medium was replaced and the .follicles were observed everyday. Granulosa cells (GC) prolification, antrum formation and oocyte maturation were recorded. Results The medium with Gn supported preantral follicle culture in vitro, during which they retained a three-dimensional structure, maintained oocytes viability and increased in diameter and number of somatic cells'. Preantral follicles cultured in Gn medium grew obviously, while those without Gn grew slowly and after 6 d's culture began to shrink and blacken. Significant increase in survival rate and maturation rate of oocytes was observed in Gn group (P〈0.01), with 92.9% survived and 28.7%formed an antrum. Further supplementation of the Gn medium with ITS and rLH, resulted in the significant increase in survival and maturation of preantral follicle (P〈0.05) Conclusions α-MEM can be the medium for in vitro culture (IVC) of preantral follicles, but need to be added with rLH/rFSH, rHCG/rEGF to facilitate thecal cell attachment, GC proliferation and oocyte maturation.展开更多
Polycystic ovary syndrome(PCOS) is the most common cause of anovulatory infertility.If PCOS infertile women fail to conceive after conventional induction of ovulation,the assisted reproductive therapy is an alternativ...Polycystic ovary syndrome(PCOS) is the most common cause of anovulatory infertility.If PCOS infertile women fail to conceive after conventional induction of ovulation,the assisted reproductive therapy is an alternative method for pregnancy.In-vitro maturation is an efficient,more economical and simple method without ovarian hyperstimulation syndrome complication。展开更多
Omega-3 polyunsaturated fatty acids(n-3 PUFAs),particularly docosahexaenoic acid(22:6n-3,DHA),play crucial roles in the reproductive health of vertebrates,including humans.Nevertheless,the underlying mechanism related...Omega-3 polyunsaturated fatty acids(n-3 PUFAs),particularly docosahexaenoic acid(22:6n-3,DHA),play crucial roles in the reproductive health of vertebrates,including humans.Nevertheless,the underlying mechanism related to this phenomenon remains largely unknown.In this study,we employed two zebrafish genetic models,i.e.,elovl2^(-/-)mutant as an endogenous DHAdeficient model and fat1(omega-3 desaturase encoding gene)transgenic zebrafish as an endogenous DHA-rich model,to investigate the effects of DHA on oocyte maturation and quality.Results show that the elovl2^(-/-)mutants had much lower fecundity and poorer oocyte quality than the wild-type controls,while the fat1 zebrafish had higher fecundity and better oocyte quality than wildtype controls.DHA deficiency in elovl2^(-/-)embryos led to defects in egg activation,poor microtubule stability,and reduced pregnenolone levels.Further study revealed that DHA promoted pregnenolone synthesis by enhancing transcription of cyp11a1,which encodes the cholesterol side-chain cleavage enzyme,thereby stabilizing microtubule assembly during oogenesis.In turn,the hypothalamic-pituitary-gonadal axis was enhanced by DHA.In conclusion,using two unique genetic models,our findings demonstrate that endogenously synthesized DHA promotes oocyte maturation and quality by promoting pregnenolone production via transcriptional regulation of cyp11a1.展开更多
BACKGROUND The exercise of limb function is the most economical and safe method to promote the maturation of arteriovenous fistula(AVF).However,due to the lack of a uni-fied exercise standard in China,many patients ha...BACKGROUND The exercise of limb function is the most economical and safe method to promote the maturation of arteriovenous fistula(AVF).However,due to the lack of a uni-fied exercise standard in China,many patients have insufficient awareness of the importance of AVF,leading to poor effectiveness of limb function exercise.The self-management education model can effectively promote patients to take pro-active health-related actions.This study focuses on the characteristics of patients during the peri-AVF period and conducts a phased limb function exercise under the guidance of the self-management education model to observe changes in fac-tors such as the maturity of AVF.AIM To assess the impact of stage-specific limb function exercises,directed by a self-management education model,on the maturation status of AVFs.METHODS This study is a randomized controlled trial involving 74 patients with forearm AVFs from the Nephrology Department of a tertiary hospital in Sichuan Province,China.Patients were randomly divided into an observation group and a control group using a random number table method.The observation group underwent tailored stage-specific limb func-tion exercises,informed by a self-management education model which took into account the unique features of AVF at various stages,in conjunction with routine care.Conversely,the control group was given standard limb function exercises along with routine care.The assessment involves the maturity of AVFs post-intervention,post-operative complications,and the self-management level of the fistula in both groups patients.Analyses were conducted using SPSS version 23.0.Count data were represented by frequency and percentage and subjected to chi-square test comparisons.Measurement data adhering to a normal distribution were presented as mean±SD.The independent samples t-test was utilized for inter-group comparisons,while the paired t-test was used for intra-group comparisons.For measurement data not fitting a normal distribution,the median and interquartile range were presented and analyzed using the Wilcoxon rank sum test.RESULTS At the 8-wk postoperative mark,the observation group demonstrated significantly higher scores in AVF symptom recognition,symptom prevention,and self-management compared to the control group(P<0.05).However,the variance in symptom management scores between the observation and control groups lacked statistical signi-ficance(P>0.05).At 4 wk after the operation,the observation group displayed a superior vessel diameter and depth from the skin of the drainage vessels in comparison to the control group(P<0.05).While the observation group did manifest elevated blood flow rates in the drainage vessels relative to the control group,this distinction was not statistically significant(P>0.05).By the 8-wk postoperative interval,the observation group outperformed the control group with notable enhancements in blood flow rates,vessel diameter,and depth from the skin of drainage vessels(P<0.01).Seven days following the procedure,the observation group manifested significantly diminished limb swelling and an overall reduced complication rate in contrast to the control group(P<0.05).The evaluation of infection,thrombosis,embolism,arterial aneurysm stenosis,and incision bleeding showed no notable differences between the two groups(P>0.05).By the 4-wk postoperative juncture,complications between the observation and control groups were statistically indistinguishable(P>0.05).CONCLUSION Stage-specific limb function exercises,under the guidance of a self-management education model,amplify the capacity of AVF patients to discern and prevent symptoms.Additionally,they expedite AVF maturation and miti-gate postoperative limb edema,underscoring their efficacy as a valuable method for the care and upkeep of AVF in hemodialysis patients.展开更多
Watermelon(Citrullus lanatus)holds global significance as a fruit with high economic and nutritional value.Exploring the regulatory network of watermelon male reproductive development is crucial for developing male st...Watermelon(Citrullus lanatus)holds global significance as a fruit with high economic and nutritional value.Exploring the regulatory network of watermelon male reproductive development is crucial for developing male sterile materials and facilitating cross-breeding.Despite its importance,there is a lack of research on the regulation mechanism of male reproductive development in watermelon.In this study,we identified that ClESR2,a VIIIb subclass member in the APETALA2/Ethylene Responsive Factor(AP2/ERF)superfamily,was a key factor in pollen development.RNA insitu hybridization confirmed significantClESR2 expression in the tapetum and pollen during the later stage of anther development.The pollens of transgenic plants showed major defects in morphology and vitality at the late development stage.The RNA-seq and protein interaction assay confirmed that ClESR2 regulates pollen morphology and fertility by interacting with key genes involved in pollen development at both transcriptional and protein levels.These suggest that Enhancer of Shoot Regeneration 2(ESR2)plays an important role in pollen maturation and vitality.This study helps understand the male reproductive development of watermelon,providing a theoretical foundation for developing male sterile materials.展开更多
The Pabdeh Formation represents organic matter enrichment in some oil fields,which can be considered a source rock.This study is based on the Rock–Eval,Iatroscan,and electron microscopy imaging results before and aft...The Pabdeh Formation represents organic matter enrichment in some oil fields,which can be considered a source rock.This study is based on the Rock–Eval,Iatroscan,and electron microscopy imaging results before and after heating the samples.We discovered this immature shale that undergoes burial and diagenesis,in which organic matter is converted into hydro-carbons.Primary migration is the process that transports hydrocarbons in the source rock.We investigated this phenomenon by developing a model that simulates hydrocarbon generation and fluid pressure during kerogen-to-hydrocarbon conversion.Microfractures initially formed at the tip/edge of kerogen and were filled with hydrocarbons,but as catagenesis progressed,the pressure caused by the volume increase of kerogen decreased due to hydrocarbon release.The transformation of solid kerogen into low-density bitumen/oil increased the pressure,leading to the development of damage zones in the source rock.The Pabdeh Formation’s small porethroats hindered effective expulsion,causing an increase in pore fluid pressure inside the initial microfractures.The stress accumulated due to hydrocarbon production,reaching the rock’s fracture strength,further contributed to damage zone development.During the expansion process,microfractures preferentially grew in low-strength pathways such as lithology changes,laminae boundaries,and pre-existing microfractures.When the porous pressure created by each kerogen overlapped,individual microfractures interconnected,forming a network of microfractures within the source rock.This research sheds light on the complex interplay between temperature,hydrocarbon generation,and the development of expulsion fractures in the Pabdeh Formation,providing valuable insights for understanding and optimizing hydrocarbon extraction in similar geological settings.展开更多
Soybean is a broadly popular and extensively cultivated crop,however,many high-yield and high-quality varieties require specific growth conditions,restricting their widespread adoption.The appropriate light conditions...Soybean is a broadly popular and extensively cultivated crop,however,many high-yield and high-quality varieties require specific growth conditions,restricting their widespread adoption.The appropriate light conditions and photoperiod must be attained for these varieties to thrive in new environments.In this study,we employed CRISPR/Cas9 to design two sgRNAs aimed at knocking out the maturity-related gene E4 in a major American soybean variety called''Jack'',which belongs to maturity group MGII.E4 gene is primarily involved in the photoperiodic flowering and maturity in soybean,making it an ideal candidate for genetic manipulation.We successfully obtained 1 homozygous E4-SG1 mutant type with 1-bp insertion,and 4 homozygous E4-SG2 mutants type with 2-bp deletion,7-bp deletion,61-bp deletion,and 1-bp insertion,respectively.The homozygous e4 mutant plants contained early termination codons devoid of transgenic elements.Additionally,no potential offtarget sites of the E4 gene were detected.A comparative analysis revealed that,unlike the wild-type,the maturity time of homozygous e4 mutants was early under both short-day and long-day conditions.These mutants offer novel germplasm resources that may be used to modify the photoperiod sensitivity and maturity of soybean,enhancing its adaptability to high-latitude regions.展开更多
BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a ...BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a case in which CCRT had a reduction effect preoperatively.A 73-year-old woman with pyelonephritis was referred to our hospital.Computed tomography revealed right hydronephrosis and a 6-cm pelvic mass.Endoscopic ultrasound-guided fine-needle biopsy(EUS-FNB)revealed squamous cell carci-noma.The patient was diagnosed with MT of MCT.Due to her poor general con-dition and renal malfunction,we selected CCRT,expecting fewer adverse effects.After CCRT,her performance status improved,and the tumor size was reduced;surgery was performed.Five months postoperatively,the patient developed dis-semination and lymph node metastases.Palliative chemotherapy was ineffective.She died 18 months after treatment initiation.CONCLUSION EUS-FNB was useful in the diagnosis of MT of MCT;CCRT suppressed the disea-se and improved quality of life.展开更多
[Objective] The study aimed to provide references for the time of oocyte maturation in vitro and enucleation in the course of sheep nuclear transfer(NT).[Method] Compared the effects of different maturation time of oo...[Objective] The study aimed to provide references for the time of oocyte maturation in vitro and enucleation in the course of sheep nuclear transfer(NT).[Method] Compared the effects of different maturation time of oocytes on enucleation efficiency and reconstructed embryo development by means of blind enucleation and fluorescence microscopy.[Result] Treatment of IVM(in vitro maturation)19-21 h was significantly higher than IVM 16-18 h treatment in oocyte maturation rate(P<0.05)and was significantly higher than IVM 22-24 h treatment in enucleation rate(P<0.05).Three treatments had no significant difference in cleavage rate and blastocyst rate(P>0.05),but IVM 19-21 h treatment was significantly higher than the other 2 treatments in average cell number of blastocysts(P<0.05).[Conclusion] The appropriate in vitro maturation time of oocytes was 19-21 h for sheep nuclear transfer,which could significantly improve the quality of blastocysts according to the cell number per blastocyst(P<0.05).展开更多
[Objective] This study aimed to improve the in vitro maturation quality of denuded porcine oocytes and provide scientific basis for establishing a stable and efficient denuded oocyte culture system. [Method] The first...[Objective] This study aimed to improve the in vitro maturation quality of denuded porcine oocytes and provide scientific basis for establishing a stable and efficient denuded oocyte culture system. [Method] The first polar body extrusion rate, oocyte glutathione (GSH) content, positive rate of brilliant cresyl blue (BCB) staining and development potential of activated oocytes or fertilized oocytes were employed as main indicators to investigate the effects of follicular mural granulosa cell (MGC) coculture on cytoplasmic maturation of cumulus cell-removal oocytes (Denuded Oocyte, DO). [Result] According to in vitro maturation results, compared with DO group, the first polar body extrusion rate of porcine oocytes in DO+MGC group was not significantly different, but the nuclear maturation process was improved and was more similar to that in COC (cumulus-oocyte complex) group. Detection of GSH content in mature oocytes showed that there was no significant difference between DO+ MGC group (optical density of 1 053.67) and COC group (optical density of 1 426.00) or between DO+MGC group and COC+GC group (optical density of 1 541.00), however, GSH content in mature oocytes of DO group (optical density of 724.67) was significantly lower than that of COC group and COC+GC group (P0.05). Detection of glucose-6-phosphate dehydrogenase (G6PDH) activity showed that there was no significant difference in BCB positive oocyte rate between DO +MGC group (88.26% ) and COC group (92.75%) or between DO+MGC group and DO group (82.86% ), however, BCB positive oocyte rate of DO group was significantly lower than that of COC group (P0.05). Furthermore, the cleavage rate and blastocyst rate of activated mature oocytes derived from DO +MGC group (94.98% and 43.67% , respectively) were significantly higher than those from DO group (52.54% and 8.97%, respectively) (P0.05), and were not significantly different compared with those from COC group (97.11% and 38.30%, respectively). In addition, the cleavage rate of fertilized oocytes derived from DO+MGC group (72.65%) showed no significant difference compared with that from DO group (63.59%), but the blastocyst rate of DO+MGC group was significantly higher than that of DO group (9.88%) (P0.05). [Conclusion] MGC coculture can significantly improve the in vitro cytoplasmic maturation quality of denuded porcine oocytes, thereby enhancing the subsequent developmental potential.展开更多
[Objective] This study aimed to investigate the appropriate concentrations of follicle-stimulating hormone(FSH), luteotropic hormone(LH) and estrodiol(E2) during in vitro maturation of Tan sheep oocytes. [Method...[Objective] This study aimed to investigate the appropriate concentrations of follicle-stimulating hormone(FSH), luteotropic hormone(LH) and estrodiol(E2) during in vitro maturation of Tan sheep oocytes. [Method] Tan sheep oocytes were divided into five groups for in vitro maturation culture: control group, FSH group(10,50, 100, 200 and 300 μg/ml FSH, respectively), LH group(5, 10, 20, 50 and 100μg/ml LH, respectively), E2group(5, 10, 25, 50 and 100 μg/ml E2, respectively), and FSH + LH group(100 μg/ml FSH + 20 μg/ml LH). The releasing rate of first polar bodies was analyzed. [Result] The maturation rate of Tan sheep oocytes in 100 μg/ml FSH + 20 μg/ml LH group reached the highest(64.64%), which was significantly higher than that in other four groups(P〈0.05); among different FSH concentrations,100 μg/ml FSH was superior to other four concentrations and the control group, exhibiting significant differences(P〈0.05); among different LH concentrations, 20 μg/ml LH was superior to other four concentrations and the control group, exhibiting significant differences(P〈0.05); among different E2 concentrations, 50 μg/ml E2 was superior to other four concentrations and the control group, exhibiting significant differences(P〈0.05). [Conclusion] Under the experimental conditions, 100 μg/ml FSH +20 μg/ml LH was the most appropriate hormone combination for in vitro maturation of Tan sheep oocytes.展开更多
The osmotic challenges facing maturing spermatozoa and their responses to them are discussed in relation to the concept of sperm maturation, defined as the increased ability of more distally recovered epididymal sperm...The osmotic challenges facing maturing spermatozoa and their responses to them are discussed in relation to the concept of sperm maturation, defined as the increased ability of more distally recovered epididymal spermatozoa to fertilize eggs when inseminated into the female tract. One explanation could be that the more distal cells are better able to regulate their volume, and reach the oviducts, as a consequence of uptake of epididymal osmolytes. Increased motility, zona binding and oolemma fusion capacities are also acquired within the epididymis and are necessary for those cells that finally arrive at the site of fertilization. (Asian J Androl 2007 July; 9: 533-539)展开更多
To investigate the longitudinal sagittal growth changes of maxilla and mandible according to the quantitative cervical vertebral maturation (QCVM) for adolescents with normal occlusion, mixed longitudinal data were ...To investigate the longitudinal sagittal growth changes of maxilla and mandible according to the quantitative cervical vertebral maturation (QCVM) for adolescents with normal occlusion, mixed longitudinal data were used. The samples included 87 adolescents aged from 8 to 18 y old with normal occlusion (32 males, 55 females) selected from 901 candidates. Sequential lateral cephalograms and hand-wrist films were taken once a year, lasting for 6 y. The longitudinal sagittal growth changes of maxilla and mandible according to QCVM were measured. There were some significant differences between maxilla and mandible according to QCVM. The sagittal growth change of maxilla showed a trend towards high velocity→decelerating velocity→completing velocity from QCVM stage Ⅰ to stage Ⅳ. The sagittal growth change of mandible showed a trend towards accelerating velocity→high velocity→decelerating velocity→completing velocity from QCVM stage Ⅰ to stage Ⅳ. With sagittal relationship, growth magnitude was almost the same between maxilla and mandible at QCVM stage Ⅰ . At stage Ⅱ the growth of mandible exceeded that of maxilla and growth in mandible continued at stages Ⅲ and IV, while the maxilla ceased to grow. Growth magnitude was greater and the growth duration was longer with male mandible. It is concluded that the longitudinal sagittal growth changes of maxilla and mandible on the basis of QCVM is of value in the orthodontic practice.展开更多
p28, a 28kD protein from toad (Bufo bufo gargarizans) oocytes, was identified by using p13sucl-agarose affinity chromatography. Sequence homology analysis of the full-length cDNA of p28 (Gene Bank accession number: AF...p28, a 28kD protein from toad (Bufo bufo gargarizans) oocytes, was identified by using p13sucl-agarose affinity chromatography. Sequence homology analysis of the full-length cDNA of p28 (Gene Bank accession number: AF 314091) indicated that it encodes a protein containing 224 amino-acids with about 55% identities and more than 70% positives to human, rat or mouse UCH-L1, and contains homological functional domains of UCH family. Anti-p28 monoclonal antibody, on injecting into the oocytes, could inhibit the progesterone-induced resumption of meiotic division in a dose-dependent manner. The recombinant protein p28 showed similar SDS/PAGE behaviors to the native one, and promoted ubiquitin ethyl ester hydrolysis, a classical catalytic reaction for ubiquitin carboxyl terminal hydrolases (UCHs). The results in this paper reveal that a novel protein, p28, exists in the toad oocytes, is a UCH L1 homolog, was engaged in the process of progesterone-induced oocyte maturation possibly through an involvement in protein turnover and degradation.展开更多
Age, maturation and population structure of the Humboldt squid Dosidicus gigas were studied based on random sampling of the Chinese jigging fishery off the Peruvian Exclusive Economic Zones (EEZ) during 2008-2010. E...Age, maturation and population structure of the Humboldt squid Dosidicus gigas were studied based on random sampling of the Chinese jigging fishery off the Peruvian Exclusive Economic Zones (EEZ) during 2008-2010. Estimated ages ranged from 144 to 633 days, confirming that the squid is a short-lived species with longevity no longer than 2 years. Occurrence of mature females and hatching in each month indicated that Humboldt squid spawned year-round. Back-calculated hatching dates for the samples were from January 22^nd, 2008 to April 22nd, 2010 with a peak between January and March. Two size-based and two hatching date-based populations could be defined from mantle length (ML) at maturity and back-calculated hatching dates, respectively. Females matured at a larger size than males, and there was a significant difference in ML at maturity between the two hatching groups (P〈0.05). The waters adjacent to 1 l^S off the Peruvian EEZ may be a potential spawning ground. This study shows the complexity of the population structure and large variability in key life history parameters in the Humboldt squid off the Peruvian EEZ, which should be considered in the assessment and management of this important resource.展开更多
With embryogenic callus of Larix olgensisis, we investigated the effects of inositol, glutamine, casein hydrolysate, carbohydrate, abscisic acid and silver nitrate concentration on the maturation of the somatic embryo...With embryogenic callus of Larix olgensisis, we investigated the effects of inositol, glutamine, casein hydrolysate, carbohydrate, abscisic acid and silver nitrate concentration on the maturation of the somatic embryo.Three dominant factors emerged, and we developed a response surface model based on the Box-Behnken design.We defined the optimal conditions for the maturation of somatic embryos. The contents of abscisic acid, silver nitrate, sucrose and casein hydrolysis significantly affected the amount of maturing embryos, but inositol, maltose and glutamine had no effect. By establishing a response surface model with multiple factors, we predicted that the optimal number of L. olgensis somatic embryos was 204 ± 4 gon basal medium, containing 18.28 mg Labscisic acid,5.46 mg Lsilver nitrate and 82.67 g Lsucrose. In the verification experiments, the addition of 20 mg Labscisic acid, 5 mg Lsilver nitrate and 80 g Lsucrose to BM yielded an average of 202.06 somatic embryos per gram. These results should guide large-scale breeding of L. olgensis.展开更多
Sperm maturation in the epididymis may involve differences between mature and immature spermatozoa in their volume regulatory osmolyte response. Spermatozoa obtained from the rat caput and cauda epididymidis were exam...Sperm maturation in the epididymis may involve differences between mature and immature spermatozoa in their volume regulatory osmolyte response. Spermatozoa obtained from the rat caput and cauda epididymidis were examined for their ability to regulate volume after transfer from in situ epididymal osmolality (measured to be 343 ± 13 and 365 ± 19 mmol kg^-1, respectively) to that of the female tract in single- and multiple-step protocols. Cells withstood the single-step treatment better than the multistep protocol. Sperm volume estimates by flow cytometric measure- ments of forward scatter of cells with intact head membranes was more sensitive than those by assessing cell coiling microscopically. At osmolalites below 210 mmol kg l both caput and cauda cells ruptured, limiting the use of flow cytometry. Above this critical value, the use of quinine showed that both caput and cauda cells could regulate volume, but cauda cells were the more effective. Of several organic osmolytes studied, myo-inositol, glutamate and KCl caused only temporary and slight swelling of spermatozoa cells in hypotonic medium. Spermatozoa of both maturities seemed to use potassium as the preferred osmolyte for regulating volume.展开更多
The changes in content of Ca2 + and CaM, Ca2 + -ATPase activity and active oxygen metabolism during strawberry (Fragaria ananassa Duch. cv. Chunxing) fruits maturation and senescence were investigated in this study. T...The changes in content of Ca2 + and CaM, Ca2 + -ATPase activity and active oxygen metabolism during strawberry (Fragaria ananassa Duch. cv. Chunxing) fruits maturation and senescence were investigated in this study. The results showed that the soluble Ca2+ content and SOD activity in fruits tended to decline and O2 production rate to increase, the Ca2 + -ATPase activity peaked at first and then declined during fruits maturation and senescence. There were the highest CaM content at white stage in preharvest fruits and at marked senescence stage in postharvest ones. The above biochemical changes in fruits stored at low temperature (4℃)were slower than those stored at normal temperature(25℃). Thus, it indicated that the stimulation of calcium messenger system and accumulation of active oxygen free radical were closely related to fruits maturation and senescence.展开更多
The reconstruction of thermal history is an important component of basin evolution and hydrocarbon exploration.Based on vitrinite reflectance data,we integrate the paleo-temperature gradient and paleo-heat flow method...The reconstruction of thermal history is an important component of basin evolution and hydrocarbon exploration.Based on vitrinite reflectance data,we integrate the paleo-temperature gradient and paleo-heat flow methods to reconstruct the thermal history of Junggar Basin.Compared with present thermal state,the Junggar Basin experienced much a higher heat flow of ca.80–120 mW/m2 during the Carboniferous.This feature can be attributed to large-scale volcanic events and related thermal effects.The hydrocarbon maturation history of Carboniferous source rocks indicates that the temperature rapidly reached the threshold of hydrocarbon generation during the Late Carboniferous and has never achieved such a high level since then.This characteristic resulted in the early maturation of hydrocarbons in Carboniferous source rocks.Meanwhile,the results reveal that hydrocarbon maturities are different among various tectonic units in Junggar Basin.The kerogen either rapidly broke through the dry gas period so that cracking of gas occurred or remained in the oil maturation window forming oil reservoirs,which depended on the tectonic background and depositional environment.In this study,we present the thermal and hydrocarbon maturation history since the Carboniferous,which has important implications for further hydrocarbon exploration in Junggar Basin.展开更多
Background: Resveratrol, an important phyto-antioxidant commonly found in grapes, mulberry, and other plants,has a variety of functions including anti-aging, anti-cancer and anti-inflammatory activities. In the curre...Background: Resveratrol, an important phyto-antioxidant commonly found in grapes, mulberry, and other plants,has a variety of functions including anti-aging, anti-cancer and anti-inflammatory activities. In the current study, we investigated the beneficial effects of resveratrol on in vitro porcine oocyte maturation under heat stress(HS). The effect of resveratrol, melatonin and their combination on alleviating HS was compared according to the maturation rate of oocytes and the development competence of embryos after parthenogenetic activation(PA).Results: Supplementation with resveratrol(2.0 μmol/L) not only improved the nuclear maturation but also raised the blastocyst rate of porcine embryos' PA from oocytes that underwent HS by increasing their glutathione(GSH)level, reducing reactive oxygen species(ROS) and up-regulating the expression of Sirtuin 1(SIRT1). It was also found that melatonin(10^-7mol/L) and the combination of resveratrol(2.0 μmol/L) plus melatonin(10^-7mol/L) exhibited more potent effects than resveratrol alone regarding their protective activities on oocyte maturation under HS.Conclusions: This study compared the efficiencies of resveratrol, melatonin and their combination for protecting porcine oocytes from heat stress. The mechanisms are attributed to the fact that each treatment may have different ability to regulate the synthesis of steroid hormones and the expression of mature related genes.展开更多
基金This study was supported by Natural Science Foundation of Shanghai(No.01ZB14037)
文摘Objective To observe the morphological changes in in vitro growth of preantral follicle isolated from prepuberal mice and to assess impacts of gonadotropin (Gn), insulin transferrin selenium (ITS) and epidermal growth factor (EGF) on their development. Methods Early preantral mice follicles (90-130μm diameter) were mechanical isolated and selected from 2 weeks' old mice and then cultured in alpha-minimal essential medium (α-MEM) with or without Gn, ITS and EGF. The preantral follicles were cultured singly in 20 miovliters droplets for up to 14 d. The medium was replaced and the .follicles were observed everyday. Granulosa cells (GC) prolification, antrum formation and oocyte maturation were recorded. Results The medium with Gn supported preantral follicle culture in vitro, during which they retained a three-dimensional structure, maintained oocytes viability and increased in diameter and number of somatic cells'. Preantral follicles cultured in Gn medium grew obviously, while those without Gn grew slowly and after 6 d's culture began to shrink and blacken. Significant increase in survival rate and maturation rate of oocytes was observed in Gn group (P〈0.01), with 92.9% survived and 28.7%formed an antrum. Further supplementation of the Gn medium with ITS and rLH, resulted in the significant increase in survival and maturation of preantral follicle (P〈0.05) Conclusions α-MEM can be the medium for in vitro culture (IVC) of preantral follicles, but need to be added with rLH/rFSH, rHCG/rEGF to facilitate thecal cell attachment, GC proliferation and oocyte maturation.
文摘Polycystic ovary syndrome(PCOS) is the most common cause of anovulatory infertility.If PCOS infertile women fail to conceive after conventional induction of ovulation,the assisted reproductive therapy is an alternative method for pregnancy.In-vitro maturation is an efficient,more economical and simple method without ovarian hyperstimulation syndrome complication。
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Precision Seed Design and Breeding,XDA24010108)National Natural Science Foundation of China(31972780&31721005)+1 种基金National Key R&D Program of China(2018YFA0801000)State Key Laboratory of Freshwater Ecology and Biotechnology(2019FBZ05)。
文摘Omega-3 polyunsaturated fatty acids(n-3 PUFAs),particularly docosahexaenoic acid(22:6n-3,DHA),play crucial roles in the reproductive health of vertebrates,including humans.Nevertheless,the underlying mechanism related to this phenomenon remains largely unknown.In this study,we employed two zebrafish genetic models,i.e.,elovl2^(-/-)mutant as an endogenous DHAdeficient model and fat1(omega-3 desaturase encoding gene)transgenic zebrafish as an endogenous DHA-rich model,to investigate the effects of DHA on oocyte maturation and quality.Results show that the elovl2^(-/-)mutants had much lower fecundity and poorer oocyte quality than the wild-type controls,while the fat1 zebrafish had higher fecundity and better oocyte quality than wildtype controls.DHA deficiency in elovl2^(-/-)embryos led to defects in egg activation,poor microtubule stability,and reduced pregnenolone levels.Further study revealed that DHA promoted pregnenolone synthesis by enhancing transcription of cyp11a1,which encodes the cholesterol side-chain cleavage enzyme,thereby stabilizing microtubule assembly during oogenesis.In turn,the hypothalamic-pituitary-gonadal axis was enhanced by DHA.In conclusion,using two unique genetic models,our findings demonstrate that endogenously synthesized DHA promotes oocyte maturation and quality by promoting pregnenolone production via transcriptional regulation of cyp11a1.
基金Supported by The Research Project 2022 of The People's Hospital of Jianyang City,No.JY202208.
文摘BACKGROUND The exercise of limb function is the most economical and safe method to promote the maturation of arteriovenous fistula(AVF).However,due to the lack of a uni-fied exercise standard in China,many patients have insufficient awareness of the importance of AVF,leading to poor effectiveness of limb function exercise.The self-management education model can effectively promote patients to take pro-active health-related actions.This study focuses on the characteristics of patients during the peri-AVF period and conducts a phased limb function exercise under the guidance of the self-management education model to observe changes in fac-tors such as the maturity of AVF.AIM To assess the impact of stage-specific limb function exercises,directed by a self-management education model,on the maturation status of AVFs.METHODS This study is a randomized controlled trial involving 74 patients with forearm AVFs from the Nephrology Department of a tertiary hospital in Sichuan Province,China.Patients were randomly divided into an observation group and a control group using a random number table method.The observation group underwent tailored stage-specific limb func-tion exercises,informed by a self-management education model which took into account the unique features of AVF at various stages,in conjunction with routine care.Conversely,the control group was given standard limb function exercises along with routine care.The assessment involves the maturity of AVFs post-intervention,post-operative complications,and the self-management level of the fistula in both groups patients.Analyses were conducted using SPSS version 23.0.Count data were represented by frequency and percentage and subjected to chi-square test comparisons.Measurement data adhering to a normal distribution were presented as mean±SD.The independent samples t-test was utilized for inter-group comparisons,while the paired t-test was used for intra-group comparisons.For measurement data not fitting a normal distribution,the median and interquartile range were presented and analyzed using the Wilcoxon rank sum test.RESULTS At the 8-wk postoperative mark,the observation group demonstrated significantly higher scores in AVF symptom recognition,symptom prevention,and self-management compared to the control group(P<0.05).However,the variance in symptom management scores between the observation and control groups lacked statistical signi-ficance(P>0.05).At 4 wk after the operation,the observation group displayed a superior vessel diameter and depth from the skin of the drainage vessels in comparison to the control group(P<0.05).While the observation group did manifest elevated blood flow rates in the drainage vessels relative to the control group,this distinction was not statistically significant(P>0.05).By the 8-wk postoperative interval,the observation group outperformed the control group with notable enhancements in blood flow rates,vessel diameter,and depth from the skin of drainage vessels(P<0.01).Seven days following the procedure,the observation group manifested significantly diminished limb swelling and an overall reduced complication rate in contrast to the control group(P<0.05).The evaluation of infection,thrombosis,embolism,arterial aneurysm stenosis,and incision bleeding showed no notable differences between the two groups(P>0.05).By the 4-wk postoperative juncture,complications between the observation and control groups were statistically indistinguishable(P>0.05).CONCLUSION Stage-specific limb function exercises,under the guidance of a self-management education model,amplify the capacity of AVF patients to discern and prevent symptoms.Additionally,they expedite AVF maturation and miti-gate postoperative limb edema,underscoring their efficacy as a valuable method for the care and upkeep of AVF in hemodialysis patients.
基金support from the National Key Research and Development Program of China(2022YFD1602000)the National Natural Science Foundation of China(32202514,U22A20498 and 32072596)+2 种基金the Joint Fund of Henan Province Science and Technology Research and Development Plan,China(222103810009)the Science and Technology Innovation Team of Shaanxi,China(2021TD-32)the China Postdoctoral Science Foundation(2022M711064 and 2023M741062).
文摘Watermelon(Citrullus lanatus)holds global significance as a fruit with high economic and nutritional value.Exploring the regulatory network of watermelon male reproductive development is crucial for developing male sterile materials and facilitating cross-breeding.Despite its importance,there is a lack of research on the regulation mechanism of male reproductive development in watermelon.In this study,we identified that ClESR2,a VIIIb subclass member in the APETALA2/Ethylene Responsive Factor(AP2/ERF)superfamily,was a key factor in pollen development.RNA insitu hybridization confirmed significantClESR2 expression in the tapetum and pollen during the later stage of anther development.The pollens of transgenic plants showed major defects in morphology and vitality at the late development stage.The RNA-seq and protein interaction assay confirmed that ClESR2 regulates pollen morphology and fertility by interacting with key genes involved in pollen development at both transcriptional and protein levels.These suggest that Enhancer of Shoot Regeneration 2(ESR2)plays an important role in pollen maturation and vitality.This study helps understand the male reproductive development of watermelon,providing a theoretical foundation for developing male sterile materials.
文摘The Pabdeh Formation represents organic matter enrichment in some oil fields,which can be considered a source rock.This study is based on the Rock–Eval,Iatroscan,and electron microscopy imaging results before and after heating the samples.We discovered this immature shale that undergoes burial and diagenesis,in which organic matter is converted into hydro-carbons.Primary migration is the process that transports hydrocarbons in the source rock.We investigated this phenomenon by developing a model that simulates hydrocarbon generation and fluid pressure during kerogen-to-hydrocarbon conversion.Microfractures initially formed at the tip/edge of kerogen and were filled with hydrocarbons,but as catagenesis progressed,the pressure caused by the volume increase of kerogen decreased due to hydrocarbon release.The transformation of solid kerogen into low-density bitumen/oil increased the pressure,leading to the development of damage zones in the source rock.The Pabdeh Formation’s small porethroats hindered effective expulsion,causing an increase in pore fluid pressure inside the initial microfractures.The stress accumulated due to hydrocarbon production,reaching the rock’s fracture strength,further contributed to damage zone development.During the expansion process,microfractures preferentially grew in low-strength pathways such as lithology changes,laminae boundaries,and pre-existing microfractures.When the porous pressure created by each kerogen overlapped,individual microfractures interconnected,forming a network of microfractures within the source rock.This research sheds light on the complex interplay between temperature,hydrocarbon generation,and the development of expulsion fractures in the Pabdeh Formation,providing valuable insights for understanding and optimizing hydrocarbon extraction in similar geological settings.
基金supported by grants from the National Key R&D Program of China (2023YFD1201300)CAAS Agricultural Science and Technology Innovation Project
文摘Soybean is a broadly popular and extensively cultivated crop,however,many high-yield and high-quality varieties require specific growth conditions,restricting their widespread adoption.The appropriate light conditions and photoperiod must be attained for these varieties to thrive in new environments.In this study,we employed CRISPR/Cas9 to design two sgRNAs aimed at knocking out the maturity-related gene E4 in a major American soybean variety called''Jack'',which belongs to maturity group MGII.E4 gene is primarily involved in the photoperiodic flowering and maturity in soybean,making it an ideal candidate for genetic manipulation.We successfully obtained 1 homozygous E4-SG1 mutant type with 1-bp insertion,and 4 homozygous E4-SG2 mutants type with 2-bp deletion,7-bp deletion,61-bp deletion,and 1-bp insertion,respectively.The homozygous e4 mutant plants contained early termination codons devoid of transgenic elements.Additionally,no potential offtarget sites of the E4 gene were detected.A comparative analysis revealed that,unlike the wild-type,the maturity time of homozygous e4 mutants was early under both short-day and long-day conditions.These mutants offer novel germplasm resources that may be used to modify the photoperiod sensitivity and maturity of soybean,enhancing its adaptability to high-latitude regions.
文摘BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a case in which CCRT had a reduction effect preoperatively.A 73-year-old woman with pyelonephritis was referred to our hospital.Computed tomography revealed right hydronephrosis and a 6-cm pelvic mass.Endoscopic ultrasound-guided fine-needle biopsy(EUS-FNB)revealed squamous cell carci-noma.The patient was diagnosed with MT of MCT.Due to her poor general con-dition and renal malfunction,we selected CCRT,expecting fewer adverse effects.After CCRT,her performance status improved,and the tumor size was reduced;surgery was performed.Five months postoperatively,the patient developed dis-semination and lymph node metastases.Palliative chemotherapy was ineffective.She died 18 months after treatment initiation.CONCLUSION EUS-FNB was useful in the diagnosis of MT of MCT;CCRT suppressed the disea-se and improved quality of life.
基金Supported by School Program of Henan Institute of Science and Technology(20060516)~~
文摘[Objective] The study aimed to provide references for the time of oocyte maturation in vitro and enucleation in the course of sheep nuclear transfer(NT).[Method] Compared the effects of different maturation time of oocytes on enucleation efficiency and reconstructed embryo development by means of blind enucleation and fluorescence microscopy.[Result] Treatment of IVM(in vitro maturation)19-21 h was significantly higher than IVM 16-18 h treatment in oocyte maturation rate(P<0.05)and was significantly higher than IVM 22-24 h treatment in enucleation rate(P<0.05).Three treatments had no significant difference in cleavage rate and blastocyst rate(P>0.05),but IVM 19-21 h treatment was significantly higher than the other 2 treatments in average cell number of blastocysts(P<0.05).[Conclusion] The appropriate in vitro maturation time of oocytes was 19-21 h for sheep nuclear transfer,which could significantly improve the quality of blastocysts according to the cell number per blastocyst(P<0.05).
基金Supported by National Natural Science Foundation of China (30871431)Outstanding Youth Fund of Heilongjiang Province (JC200905)~~
文摘[Objective] This study aimed to improve the in vitro maturation quality of denuded porcine oocytes and provide scientific basis for establishing a stable and efficient denuded oocyte culture system. [Method] The first polar body extrusion rate, oocyte glutathione (GSH) content, positive rate of brilliant cresyl blue (BCB) staining and development potential of activated oocytes or fertilized oocytes were employed as main indicators to investigate the effects of follicular mural granulosa cell (MGC) coculture on cytoplasmic maturation of cumulus cell-removal oocytes (Denuded Oocyte, DO). [Result] According to in vitro maturation results, compared with DO group, the first polar body extrusion rate of porcine oocytes in DO+MGC group was not significantly different, but the nuclear maturation process was improved and was more similar to that in COC (cumulus-oocyte complex) group. Detection of GSH content in mature oocytes showed that there was no significant difference between DO+ MGC group (optical density of 1 053.67) and COC group (optical density of 1 426.00) or between DO+MGC group and COC+GC group (optical density of 1 541.00), however, GSH content in mature oocytes of DO group (optical density of 724.67) was significantly lower than that of COC group and COC+GC group (P0.05). Detection of glucose-6-phosphate dehydrogenase (G6PDH) activity showed that there was no significant difference in BCB positive oocyte rate between DO +MGC group (88.26% ) and COC group (92.75%) or between DO+MGC group and DO group (82.86% ), however, BCB positive oocyte rate of DO group was significantly lower than that of COC group (P0.05). Furthermore, the cleavage rate and blastocyst rate of activated mature oocytes derived from DO +MGC group (94.98% and 43.67% , respectively) were significantly higher than those from DO group (52.54% and 8.97%, respectively) (P0.05), and were not significantly different compared with those from COC group (97.11% and 38.30%, respectively). In addition, the cleavage rate of fertilized oocytes derived from DO+MGC group (72.65%) showed no significant difference compared with that from DO group (63.59%), but the blastocyst rate of DO+MGC group was significantly higher than that of DO group (9.88%) (P0.05). [Conclusion] MGC coculture can significantly improve the in vitro cytoplasmic maturation quality of denuded porcine oocytes, thereby enhancing the subsequent developmental potential.
基金Supported by Natural Science Foundation of Ningxia Hui Autonomous Region(NZ12150)~~
文摘[Objective] This study aimed to investigate the appropriate concentrations of follicle-stimulating hormone(FSH), luteotropic hormone(LH) and estrodiol(E2) during in vitro maturation of Tan sheep oocytes. [Method] Tan sheep oocytes were divided into five groups for in vitro maturation culture: control group, FSH group(10,50, 100, 200 and 300 μg/ml FSH, respectively), LH group(5, 10, 20, 50 and 100μg/ml LH, respectively), E2group(5, 10, 25, 50 and 100 μg/ml E2, respectively), and FSH + LH group(100 μg/ml FSH + 20 μg/ml LH). The releasing rate of first polar bodies was analyzed. [Result] The maturation rate of Tan sheep oocytes in 100 μg/ml FSH + 20 μg/ml LH group reached the highest(64.64%), which was significantly higher than that in other four groups(P〈0.05); among different FSH concentrations,100 μg/ml FSH was superior to other four concentrations and the control group, exhibiting significant differences(P〈0.05); among different LH concentrations, 20 μg/ml LH was superior to other four concentrations and the control group, exhibiting significant differences(P〈0.05); among different E2 concentrations, 50 μg/ml E2 was superior to other four concentrations and the control group, exhibiting significant differences(P〈0.05). [Conclusion] Under the experimental conditions, 100 μg/ml FSH +20 μg/ml LH was the most appropriate hormone combination for in vitro maturation of Tan sheep oocytes.
文摘The osmotic challenges facing maturing spermatozoa and their responses to them are discussed in relation to the concept of sperm maturation, defined as the increased ability of more distally recovered epididymal spermatozoa to fertilize eggs when inseminated into the female tract. One explanation could be that the more distal cells are better able to regulate their volume, and reach the oviducts, as a consequence of uptake of epididymal osmolytes. Increased motility, zona binding and oolemma fusion capacities are also acquired within the epididymis and are necessary for those cells that finally arrive at the site of fertilization. (Asian J Androl 2007 July; 9: 533-539)
基金supported by a grant from the National Natural Sciences Foundation of China (No.30801314)
文摘To investigate the longitudinal sagittal growth changes of maxilla and mandible according to the quantitative cervical vertebral maturation (QCVM) for adolescents with normal occlusion, mixed longitudinal data were used. The samples included 87 adolescents aged from 8 to 18 y old with normal occlusion (32 males, 55 females) selected from 901 candidates. Sequential lateral cephalograms and hand-wrist films were taken once a year, lasting for 6 y. The longitudinal sagittal growth changes of maxilla and mandible according to QCVM were measured. There were some significant differences between maxilla and mandible according to QCVM. The sagittal growth change of maxilla showed a trend towards high velocity→decelerating velocity→completing velocity from QCVM stage Ⅰ to stage Ⅳ. The sagittal growth change of mandible showed a trend towards accelerating velocity→high velocity→decelerating velocity→completing velocity from QCVM stage Ⅰ to stage Ⅳ. With sagittal relationship, growth magnitude was almost the same between maxilla and mandible at QCVM stage Ⅰ . At stage Ⅱ the growth of mandible exceeded that of maxilla and growth in mandible continued at stages Ⅲ and IV, while the maxilla ceased to grow. Growth magnitude was greater and the growth duration was longer with male mandible. It is concluded that the longitudinal sagittal growth changes of maxilla and mandible on the basis of QCVM is of value in the orthodontic practice.
基金This work is supported by National Natural Sci-ence Fundation of China (Grant 39770370), and National Laboratory of Contraceptives and Devices Re-search affiliated with Shanghai lnstitute of Planned Parenthood Research.
文摘p28, a 28kD protein from toad (Bufo bufo gargarizans) oocytes, was identified by using p13sucl-agarose affinity chromatography. Sequence homology analysis of the full-length cDNA of p28 (Gene Bank accession number: AF 314091) indicated that it encodes a protein containing 224 amino-acids with about 55% identities and more than 70% positives to human, rat or mouse UCH-L1, and contains homological functional domains of UCH family. Anti-p28 monoclonal antibody, on injecting into the oocytes, could inhibit the progesterone-induced resumption of meiotic division in a dose-dependent manner. The recombinant protein p28 showed similar SDS/PAGE behaviors to the native one, and promoted ubiquitin ethyl ester hydrolysis, a classical catalytic reaction for ubiquitin carboxyl terminal hydrolases (UCHs). The results in this paper reveal that a novel protein, p28, exists in the toad oocytes, is a UCH L1 homolog, was engaged in the process of progesterone-induced oocyte maturation possibly through an involvement in protein turnover and degradation.
基金Supported by the National Natural Science Foundation of China (No.41276156)the National High Technology Research and Development Program of China (863 Program) (No. 2012AA092303)+3 种基金the Innovation Program of Shanghai Municipal Education Commission (No. 13YZ091)Shanghai Leading Academic Disciplin Projectsupported by National Distant-Water Fisheries Engineering Research Center, and Scientific Observing and Experimental Station of Oceanic Fishery Resources, Ministry of AgricultureYong Chen’s involvement in the project was supported by the Shanghai Dongfang Scholar Program
文摘Age, maturation and population structure of the Humboldt squid Dosidicus gigas were studied based on random sampling of the Chinese jigging fishery off the Peruvian Exclusive Economic Zones (EEZ) during 2008-2010. Estimated ages ranged from 144 to 633 days, confirming that the squid is a short-lived species with longevity no longer than 2 years. Occurrence of mature females and hatching in each month indicated that Humboldt squid spawned year-round. Back-calculated hatching dates for the samples were from January 22^nd, 2008 to April 22nd, 2010 with a peak between January and March. Two size-based and two hatching date-based populations could be defined from mantle length (ML) at maturity and back-calculated hatching dates, respectively. Females matured at a larger size than males, and there was a significant difference in ML at maturity between the two hatching groups (P〈0.05). The waters adjacent to 1 l^S off the Peruvian EEZ may be a potential spawning ground. This study shows the complexity of the population structure and large variability in key life history parameters in the Humboldt squid off the Peruvian EEZ, which should be considered in the assessment and management of this important resource.
基金supported by the National High-tech R&D Program(863 Program)of China(2013AA102704)
文摘With embryogenic callus of Larix olgensisis, we investigated the effects of inositol, glutamine, casein hydrolysate, carbohydrate, abscisic acid and silver nitrate concentration on the maturation of the somatic embryo.Three dominant factors emerged, and we developed a response surface model based on the Box-Behnken design.We defined the optimal conditions for the maturation of somatic embryos. The contents of abscisic acid, silver nitrate, sucrose and casein hydrolysis significantly affected the amount of maturing embryos, but inositol, maltose and glutamine had no effect. By establishing a response surface model with multiple factors, we predicted that the optimal number of L. olgensis somatic embryos was 204 ± 4 gon basal medium, containing 18.28 mg Labscisic acid,5.46 mg Lsilver nitrate and 82.67 g Lsucrose. In the verification experiments, the addition of 20 mg Labscisic acid, 5 mg Lsilver nitrate and 80 g Lsucrose to BM yielded an average of 202.06 somatic embryos per gram. These results should guide large-scale breeding of L. olgensis.
文摘Sperm maturation in the epididymis may involve differences between mature and immature spermatozoa in their volume regulatory osmolyte response. Spermatozoa obtained from the rat caput and cauda epididymidis were examined for their ability to regulate volume after transfer from in situ epididymal osmolality (measured to be 343 ± 13 and 365 ± 19 mmol kg^-1, respectively) to that of the female tract in single- and multiple-step protocols. Cells withstood the single-step treatment better than the multistep protocol. Sperm volume estimates by flow cytometric measure- ments of forward scatter of cells with intact head membranes was more sensitive than those by assessing cell coiling microscopically. At osmolalites below 210 mmol kg l both caput and cauda cells ruptured, limiting the use of flow cytometry. Above this critical value, the use of quinine showed that both caput and cauda cells could regulate volume, but cauda cells were the more effective. Of several organic osmolytes studied, myo-inositol, glutamate and KCl caused only temporary and slight swelling of spermatozoa cells in hypotonic medium. Spermatozoa of both maturities seemed to use potassium as the preferred osmolyte for regulating volume.
基金the National Natural Science Foundation of China ( No.30270933).
文摘The changes in content of Ca2 + and CaM, Ca2 + -ATPase activity and active oxygen metabolism during strawberry (Fragaria ananassa Duch. cv. Chunxing) fruits maturation and senescence were investigated in this study. The results showed that the soluble Ca2+ content and SOD activity in fruits tended to decline and O2 production rate to increase, the Ca2 + -ATPase activity peaked at first and then declined during fruits maturation and senescence. There were the highest CaM content at white stage in preharvest fruits and at marked senescence stage in postharvest ones. The above biochemical changes in fruits stored at low temperature (4℃)were slower than those stored at normal temperature(25℃). Thus, it indicated that the stimulation of calcium messenger system and accumulation of active oxygen free radical were closely related to fruits maturation and senescence.
基金supported by the National Natural Science Foundation of China(No.41502236 and 41877210)the National Foundation for Science and Technology Development(No.2017ZX05008-004).
文摘The reconstruction of thermal history is an important component of basin evolution and hydrocarbon exploration.Based on vitrinite reflectance data,we integrate the paleo-temperature gradient and paleo-heat flow methods to reconstruct the thermal history of Junggar Basin.Compared with present thermal state,the Junggar Basin experienced much a higher heat flow of ca.80–120 mW/m2 during the Carboniferous.This feature can be attributed to large-scale volcanic events and related thermal effects.The hydrocarbon maturation history of Carboniferous source rocks indicates that the temperature rapidly reached the threshold of hydrocarbon generation during the Late Carboniferous and has never achieved such a high level since then.This characteristic resulted in the early maturation of hydrocarbons in Carboniferous source rocks.Meanwhile,the results reveal that hydrocarbon maturities are different among various tectonic units in Junggar Basin.The kerogen either rapidly broke through the dry gas period so that cracking of gas occurred or remained in the oil maturation window forming oil reservoirs,which depended on the tectonic background and depositional environment.In this study,we present the thermal and hydrocarbon maturation history since the Carboniferous,which has important implications for further hydrocarbon exploration in Junggar Basin.
基金supported by programs for the 973 National Basic Research Program of China (2014CB138505)the Open Foundation of State Key Laboratory of Animal Nutrition (2004DA115184F1415)
文摘Background: Resveratrol, an important phyto-antioxidant commonly found in grapes, mulberry, and other plants,has a variety of functions including anti-aging, anti-cancer and anti-inflammatory activities. In the current study, we investigated the beneficial effects of resveratrol on in vitro porcine oocyte maturation under heat stress(HS). The effect of resveratrol, melatonin and their combination on alleviating HS was compared according to the maturation rate of oocytes and the development competence of embryos after parthenogenetic activation(PA).Results: Supplementation with resveratrol(2.0 μmol/L) not only improved the nuclear maturation but also raised the blastocyst rate of porcine embryos' PA from oocytes that underwent HS by increasing their glutathione(GSH)level, reducing reactive oxygen species(ROS) and up-regulating the expression of Sirtuin 1(SIRT1). It was also found that melatonin(10^-7mol/L) and the combination of resveratrol(2.0 μmol/L) plus melatonin(10^-7mol/L) exhibited more potent effects than resveratrol alone regarding their protective activities on oocyte maturation under HS.Conclusions: This study compared the efficiencies of resveratrol, melatonin and their combination for protecting porcine oocytes from heat stress. The mechanisms are attributed to the fact that each treatment may have different ability to regulate the synthesis of steroid hormones and the expression of mature related genes.