Apoptosis in mammalian oocytes: a review

Abstract Apoptosis causes elimination of more than 99 % of germ cells from cohort of ovary through follicular atresia. Less than 1 % of germ cells, which are culminated in oocytes further undergo apoptosis during last phases of oogenesis and depletes ovarian reserve in most of the mammalian species including human. There are several players that induce apoptosis directly or indirectly in oocytes at various stages of meiotic cell cycle. Premature removal of encircling granulosa cells from immature oocytes, reduced levels of adenosine 3′,5′-cyclic monophosphate and guanosine 3′,5′-cyclic monophosphate, increased levels of calcium (Ca2+) and oxidants, sustained reduced level of maturation promoting factor, depletion of survival factors, nutrients and cell cycle proteins, reduced meiotic competency, increased levels of proapoptotic as well as apoptotic factors lead to oocyte apoptosis. The BH3-only proteins also act as key regulators of apoptosis in oocyte within the ovary. Both intrinsic (mitochondria-mediated) as well as extrinsic (cell surface death receptor-mediated) pathways are involved in oocyte apoptosis. BID, a BH3-only protein act as a bridge between both apoptotic pathways and its cleavage activates cell death machinery of both the pathways inside the follicular microenvironment. Oocyte apoptosis leads to the depletion of ovarian reserve that directly affects reproductive outcome of various mammals including human. In this rev...
Source: Apoptosis - Category: Molecular Biology Source Type: research

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Conclusion: A four-year follow-up evaluation revealed successful maintenance of the treatment results.RESUMO Introdu ção: A má oclusão de Classe III esquelética com assimetria é um dos problemas mais difíceis de se corrigir na Ortodontia. O desvio funcional da mandíbula em pacientes em fase de crescimento pode ocorrer acompanhado da Classe III, devido à atresia maxilar e interferências oclusais. Estudos têm indicado que a mordida cruzada posterior unilateral se desenvolve precocemente e apresenta baixo índice de correção espont&...
Source: Dental Press Journal of Orthodontics - Category: Dentistry Source Type: research
Conclusion: A four-year follow-up evaluation revealed successful maintenance of the treatment results.RESUMO Introdu ção: A má oclusão de Classe III esquelética com assimetria é um dos problemas mais difíceis de se corrigir na Ortodontia. O desvio funcional da mandíbula em pacientes em fase de crescimento pode ocorrer acompanhado da Classe III, devido à atresia maxilar e interferências oclusais. Estudos têm indicado que a mordida cruzada posterior unilateral se desenvolve precocemente e apresenta baixo índice de correção espont&...
Source: Dental Press Journal of Orthodontics - Category: Dentistry Source Type: research
AbstractDuctal stenting (DS) palliates duct-dependent lesions using coronary stents. Sirolimus-eluting stents have replaced bare-metal stents in coronary interventions. Concerns exist about sirolimus levels in neonates. Therapeutic immunosuppressive sirolimus level is 5 –15 ng/ml. After neonatal DS, drug levels were assessed at 24 h, 7 days and monthly thereafter till they were undetectable. Clinical course, ductal patency till their final corrective surgery was analyzed. The exact quantity of sirolimus in each stent was known. Twelve neonates with median age o f 5.5 days received sirolimus-eluting ste...
Source: Mammalian Genome - Category: Genetics & Stem Cells Source Type: research
CONCLUSION: Placement of a mometasone drug-eluting stent is a promising method to improve postoperative results and management of choanal atresia repair by limiting the need for repeat anesthetics and OR procedures, as well as the complications of traditional stents. PMID: 32468891 [PubMed - as supplied by publisher]
Source: The Annals of Otology, Rhinology, and Laryngology - Category: ENT & OMF Authors: Tags: Ann Otol Rhinol Laryngol Source Type: research
Early distinguishing biliary atresia from other causes of infantile cholestasis remains a major challenge. We aimed to develop and validate a scoring system based on bile acid for identification of biliary atr...
Source: BMC Pediatrics - Category: Pediatrics Authors: Tags: Research article Source Type: research
To evaluate the role of nebulized N-acetyl cysteine (NAC) in liquefying the airway secretions and improving the outcome of patients of esophageal atresia with tracheoesophageal fistula (EA  + TEF).
Source: Journal of Pediatric Surgery - Category: Surgery Authors: Source Type: research
In conclusion, the reported prevalence of scoliosis varies widely but on average affects about one in eight children after open repair of EA/TEF. Most cases are mild and do not require intervention. It is currently uncertain whether secondary scoliosis is preventable by using meticulous thoracotomy techniques or thoracoscopic repair.Level of evidence IV.
Source: Pediatric Surgery International - Category: Surgery Source Type: research
Objectives: Acute-on-chronic liver failure (ACLF) is well-studied in adults and characterized by decompensated cirrhosis, multi-organ failure, and early mortality. Studies of ACLF in children are limited. We sought to characterize the prevalence and clinical factors associated with pediatric ACLF (PACLF). Methods: A retrospective review of children 3 months to 18 years listed for liver transplantation and hospitalized for decompensated cirrhosis between January 2007 and December 2017 at a single pediatric hospital. Primary outcome was the development of PACLF, characterized as failure of at least 1 extrahepatic organ ...
Source: Journal of Pediatric Gastroenterology and Nutrition - Category: Gastroenterology Tags: Original Articles: Hepatology Source Type: research
Background: Biliary atresia's (BA) response to surgical Kasai portoenterostomy (KP) is uneven and dependent upon bile flow; 50% of infants require a liver transplant by 24 months. We hypothesized that the microbiome may identify and associate with outcomes in BA. Methods: Stool samples were collected from infants with cholestasis (n = 15), 8 of which with BA were followed longitudinally.16S sequencing was performed on all samples (n = 45). Whole Genome Sequencing (WGS) was performed on BA pre-KP samples (n = 8). Infants with BA, other forms of cholestasis, BA infants with very good bile flow (VGBF) and not...
Source: Journal of Pediatric Gastroenterology and Nutrition - Category: Gastroenterology Tags: Rapid Communication: Hepatology Source Type: research
The objectives of the present study were to assess the prevalence of abnormal oral glucose tolerance test (OGTT) at 3 months of age in infants operated at birth with type C OA, to describe symptoms and clinical features, and to assess risk factors in infants presenting with abnormal OGTT suggestive of DS. Methods: A prospective case series study including infants with type C OA without fundoplication, born between 2013 and 2016 in 8 centres was conducted. An OGTT was performed between 2.5 and 3.5 months. Abnormal OGTT was defined as early hyperglycaemia (>1.8 g/L until 30 minutes;>1.7 g/L between 30 minutes an...
Source: Journal of Pediatric Gastroenterology and Nutrition - Category: Gastroenterology Tags: Original Articles: Gastroenterology Source Type: research
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