The fertility of sows mainly depends on the embryo losses during gestation and the survival rate of the postfarrowing piglets.The selection of highly-prolific sows has been mainly focused on the selection of genotypes...The fertility of sows mainly depends on the embryo losses during gestation and the survival rate of the postfarrowing piglets.The selection of highly-prolific sows has been mainly focused on the selection of genotypes with high ovulatory quota.However,in the early-and post-implantation stages,the rate of embryo losses was increased with the increase of zygotes.Among the various factors,placental growth and development is the vital determinant for fetal survival,growth,and development.Despite the potential survival of fetuses with deficient placental development,their life-conditions and growth can be damaged by a process termed intrauterine growth retardation(IUGR).The newborn piglets affected by IUGR are prone to increased morbidity and mortality rates;meanwhile,the growth,health and welfare of the surviving piglets will remain hampered by these conditions,with a tendency to exacerbate with age.Functional amino acids such as glycine,proline,and arginine continue to increase with the development of placenta,which are not only essential to placental growth(including vascular growth)and development,but can also be used as substrates for the production of glutathione,polyamines and nitric oxide to benefit placental function in many ways.However,the exact regulation mechanism of these amino acids in placental function has not yet been clarified.In this review,we provide evidence from literature and our own work for the role and mechanism of dietary functional amino acids during pregnancy in regulating the placental functional response to fetal loss and birth weight of piglets.This review will provide novel insights into the response of nutritionally nonessential amino acids(glycine and proline)to placental development as well as feasible strategies to enhance the fertility of sows.展开更多
Objective: Amniocentesis is an invasive cytogenic test traditionally associated with a 1/200 procedure–related pregnancy loss rate. Recent studies have questioned the validity of the traditionally stated rate. The pu...Objective: Amniocentesis is an invasive cytogenic test traditionally associated with a 1/200 procedure–related pregnancy loss rate. Recent studies have questioned the validity of the traditionally stated rate. The purpose of this study was to document the results of second-trimes- ter genetic amniocentesis performed at our pe- rinatalogy clinic. Study Design: A retrospective review of all the amniocentesis procedures per- formed between 15 and 22 weeks of gestation on singleton pregnancies between May 2004 and December 2008 was performed. Spontaneous loss was defined as any unintentional preg- nancy loss at < 24 weeks of gestation. Setting: Zonguldak Karaelmas University, Faculty of Me- dicine, Department of Obstetrics and Gynecology. Population: Pregnant women followed at the Obstetrics Department. Methods: A retrospective review of all the amniocentesis procedures performed between May 2004 and December 2008 was performed. Main outcome measure: Pregnancy loss due to amniocentesis. Results: A total of 447 amniocentesis procedures were performed during the study period. The major indication for amniocentesis was positive maternal triple screening (44%). The mean gestational age at amniocentesis was 18.80 ± 2.70 weeks. The results of cytogenetic analyses revealed an abnormal karyotype in 19 pregnancies (4.3%), nine of which were trisomy 21. The overall spontaneous loss rate was 0.89% (n = 4). Conclusion: It would be useful for each center to investigate its own pregnancy loss rate and thereby provide a firmer basis for its policy for counseling women requesting amniocentesis. If enough such investigations were reported, a true benchmark figure could also emerge.展开更多
Fertile chicken eggs were used as an alternative model for large animals to evaluate suspect toxic dietary ingredients for fetal loss disorders associated with mare reproductive loss syndrome(MRLS) and fetal losses in...Fertile chicken eggs were used as an alternative model for large animals to evaluate suspect toxic dietary ingredients for fetal loss disorders associated with mare reproductive loss syndrome(MRLS) and fetal losses in other livestock.Nitrate,ammonia,and sulfate may react with proteinaceous compounds to enable the formation of abiotic pathogenic nanoparticles which were constant findings in pathognomonic placental lesions associated with non-infectious fetal losses of previously unknown etiology in mares,chickens and other livestock.The pathogenic nanoparticles may be produced naturally by toxic elements associated with air pollution that affect pasture forages or crops,uninte ntionally by reactions of these elements in protein-mineral mixes in dietary rations,or endogenously within tissues of fetuses and adult animals.The nanoparticles may form niduses in small vessels and predispose animals to a host of secondary opportunistic diseases affecting the reproductive,respiratory and gastrointestinal tracts of animals.The newly recognized abiotic pathogenic micro and nanoparticles are associated with MRLS.The discovery of the pathogenic nanoparticles led to the identification of nitrate,ammonium,and sulfur,in the form of sulfate,that seemingly enable the formation of the pathogenic nanoparticles in embryonic and fetal tissues.展开更多
Chorionic villi and fetal tissues from 50 pathological human conceptions at gestational weeks 9-40 were cultured and cytogenetically analyzed to explore the existence of chromosomal mosaicism confined to the extraembr...Chorionic villi and fetal tissues from 50 pathological human conceptions at gestational weeks 9-40 were cultured and cytogenetically analyzed to explore the existence of chromosomal mosaicism confined to the extraembryonic tissues and to clarify the relationship between confined placental mosaicism and adverse outcome of pregnancy. Chorionic villi and fetal tissues from 12 second trimester gestations terminated for social reasons served as a control group. In two pathological gestations, true mosaicism was found exclusively in chorionic cells and could not be confirmed in cells derived from the fetal tissues. One of these was severely growth retarded. Concordant results were obtained in all other cases.展开更多
目的:系统评价胎儿丢失女性悲伤体验的质性研究,全面了解女性悲伤及应对策略。方法:检索PubMed、Embase、Web of Science、CINAHL、中国知网、万方、维普、中国生物医学文献数据库,纳入所有符合要求的质性研究。采用Meta整合的方法对结...目的:系统评价胎儿丢失女性悲伤体验的质性研究,全面了解女性悲伤及应对策略。方法:检索PubMed、Embase、Web of Science、CINAHL、中国知网、万方、维普、中国生物医学文献数据库,纳入所有符合要求的质性研究。采用Meta整合的方法对结果进行整合。结果:共纳入21篇研究,提炼出33个研究结果,形成7个类别,最终得出3个整合结果:胎儿丢失所致的悲伤易被低估;复杂的悲伤体验;悲伤应对之旅。结论:医护人员应认识胎儿丢失女性的悲伤,尤其关注她们的个性化需求,提供个体化支持,帮助女性认识悲伤,接纳悲伤,走出悲伤,开始新的生活。展开更多
基金jointly supported by the National Key R&D Program of China (2021YFD1300401)National Natural Science Foundation of China(31902165)Natural Science Foundation of Guangdong Province(2021A1515012116)
文摘The fertility of sows mainly depends on the embryo losses during gestation and the survival rate of the postfarrowing piglets.The selection of highly-prolific sows has been mainly focused on the selection of genotypes with high ovulatory quota.However,in the early-and post-implantation stages,the rate of embryo losses was increased with the increase of zygotes.Among the various factors,placental growth and development is the vital determinant for fetal survival,growth,and development.Despite the potential survival of fetuses with deficient placental development,their life-conditions and growth can be damaged by a process termed intrauterine growth retardation(IUGR).The newborn piglets affected by IUGR are prone to increased morbidity and mortality rates;meanwhile,the growth,health and welfare of the surviving piglets will remain hampered by these conditions,with a tendency to exacerbate with age.Functional amino acids such as glycine,proline,and arginine continue to increase with the development of placenta,which are not only essential to placental growth(including vascular growth)and development,but can also be used as substrates for the production of glutathione,polyamines and nitric oxide to benefit placental function in many ways.However,the exact regulation mechanism of these amino acids in placental function has not yet been clarified.In this review,we provide evidence from literature and our own work for the role and mechanism of dietary functional amino acids during pregnancy in regulating the placental functional response to fetal loss and birth weight of piglets.This review will provide novel insights into the response of nutritionally nonessential amino acids(glycine and proline)to placental development as well as feasible strategies to enhance the fertility of sows.
文摘Objective: Amniocentesis is an invasive cytogenic test traditionally associated with a 1/200 procedure–related pregnancy loss rate. Recent studies have questioned the validity of the traditionally stated rate. The purpose of this study was to document the results of second-trimes- ter genetic amniocentesis performed at our pe- rinatalogy clinic. Study Design: A retrospective review of all the amniocentesis procedures per- formed between 15 and 22 weeks of gestation on singleton pregnancies between May 2004 and December 2008 was performed. Spontaneous loss was defined as any unintentional preg- nancy loss at < 24 weeks of gestation. Setting: Zonguldak Karaelmas University, Faculty of Me- dicine, Department of Obstetrics and Gynecology. Population: Pregnant women followed at the Obstetrics Department. Methods: A retrospective review of all the amniocentesis procedures performed between May 2004 and December 2008 was performed. Main outcome measure: Pregnancy loss due to amniocentesis. Results: A total of 447 amniocentesis procedures were performed during the study period. The major indication for amniocentesis was positive maternal triple screening (44%). The mean gestational age at amniocentesis was 18.80 ± 2.70 weeks. The results of cytogenetic analyses revealed an abnormal karyotype in 19 pregnancies (4.3%), nine of which were trisomy 21. The overall spontaneous loss rate was 0.89% (n = 4). Conclusion: It would be useful for each center to investigate its own pregnancy loss rate and thereby provide a firmer basis for its policy for counseling women requesting amniocentesis. If enough such investigations were reported, a true benchmark figure could also emerge.
基金supported in part by the Hatch project No.KY014039the Department of Veterinary Science,University of Kentucky,Lexington,KY
文摘Fertile chicken eggs were used as an alternative model for large animals to evaluate suspect toxic dietary ingredients for fetal loss disorders associated with mare reproductive loss syndrome(MRLS) and fetal losses in other livestock.Nitrate,ammonia,and sulfate may react with proteinaceous compounds to enable the formation of abiotic pathogenic nanoparticles which were constant findings in pathognomonic placental lesions associated with non-infectious fetal losses of previously unknown etiology in mares,chickens and other livestock.The pathogenic nanoparticles may be produced naturally by toxic elements associated with air pollution that affect pasture forages or crops,uninte ntionally by reactions of these elements in protein-mineral mixes in dietary rations,or endogenously within tissues of fetuses and adult animals.The nanoparticles may form niduses in small vessels and predispose animals to a host of secondary opportunistic diseases affecting the reproductive,respiratory and gastrointestinal tracts of animals.The newly recognized abiotic pathogenic micro and nanoparticles are associated with MRLS.The discovery of the pathogenic nanoparticles led to the identification of nitrate,ammonium,and sulfur,in the form of sulfate,that seemingly enable the formation of the pathogenic nanoparticles in embryonic and fetal tissues.
文摘Chorionic villi and fetal tissues from 50 pathological human conceptions at gestational weeks 9-40 were cultured and cytogenetically analyzed to explore the existence of chromosomal mosaicism confined to the extraembryonic tissues and to clarify the relationship between confined placental mosaicism and adverse outcome of pregnancy. Chorionic villi and fetal tissues from 12 second trimester gestations terminated for social reasons served as a control group. In two pathological gestations, true mosaicism was found exclusively in chorionic cells and could not be confirmed in cells derived from the fetal tissues. One of these was severely growth retarded. Concordant results were obtained in all other cases.
文摘目的:系统评价胎儿丢失女性悲伤体验的质性研究,全面了解女性悲伤及应对策略。方法:检索PubMed、Embase、Web of Science、CINAHL、中国知网、万方、维普、中国生物医学文献数据库,纳入所有符合要求的质性研究。采用Meta整合的方法对结果进行整合。结果:共纳入21篇研究,提炼出33个研究结果,形成7个类别,最终得出3个整合结果:胎儿丢失所致的悲伤易被低估;复杂的悲伤体验;悲伤应对之旅。结论:医护人员应认识胎儿丢失女性的悲伤,尤其关注她们的个性化需求,提供个体化支持,帮助女性认识悲伤,接纳悲伤,走出悲伤,开始新的生活。
