摘要:

AbstractFurther studies on a family with the N syndrome, a multiple congenital anomaly/ mental retardation syndrome first described by Hess et al in 1974, showed increased chromosome breakage in the affected brothers and in their unaffected mother, all 3 of whom died of lymphoid malignancy. It is suggested that the N syndrome is the result of an X‐linked recessive mutation that produces a characteristic MCA/MR syndrome and chromosome instability. We postulate that this chromosome instability in the lymphoid cells of hemizygotes and in approximately half of the lymphoid cells of the heterozygote predisposes to a specific form of lymphoid malignanc

ISSN:0148-7299    

DOI:10.1002/ajmg.1320280544

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractWe have studied an infant with respiratory distress, absent fifth rays of the hands, and hydrometrocolpos. Congenital absence of the fifth ray of the hand is a rare malforma‐tion. In some syndromes the ulnar defects are symmetrical; however, as an isolated anomaly the defects are usually asymmetric. This patient's malformations appear to be unique in that the ulnar ray was affected bilaterally, with an associated genital malformatio

ISSN:0148-7299    

DOI:10.1002/ajmg.1320280545

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractWe describe 9 cases of Meckel syndrome (dysencephalia splanchnocystica), ranging in gestational age from 17 to 39 weeks. Five were liveborn, and the longest survival was 30 hours. Six of the 9 had all 3 elements of the classically defined triad, namely occipital encephalocele, renal cystic dysplasia, and postaxial polydactyly. The remaining 3 cases had only 2 elements of the triad.The renal abnormalities in the 9 cases resembled one another closely, varying only slightly in severity. They consisted of renal cystic dysplasia with different degrees of nephronic differentiation.The 8 available livers all contained intrahepatic bile duct anomalies. Seven of them had the classic “ductal plate malformation,” as defined by Jorgensen [1977]; the had the classic “ductal plate malformation,” as defined by Jorgensen [1977]; the remaining case had a less severe form of this malformation. The livers of the Meckel syndrome fetuses were compared to those of age‐matched control fetuses, and it was concluded that the hepatic abnormality represents an arrested developmetn of the intrahepatic biliary system at the stage of biliary cylinders with varying degrees of the reactive bile duct proliferation, bile duct dilatation, portal fibrosis, and portal fibrous vascular obliteration superimposed on the arrested pattern. The case showing the least severe hepatic lesion also had the least severe renal lesion.The anomalies that were present are listed. The relationship of the different lesions to each other is briefly discussed.It was concluded that the hepatic lesion appears to be a consistent manifestation in Meckel syndrome and is of diagnostic value as the renal lesion has previously been sh

ISSN:0148-7299    

DOI:10.1002/ajmg.1320280546

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractCardiovascular malformations are the second most common type of birth defect, occurring in 5–8/1,000 livebirths with a still higher prevalence among stillborn infants and spontaneously aborted embryos and fetuses. Dealing effectively with the high frequency of heart defects means reducing the incidence of cardiac malformations in the world. In this paper we cite some of the genetic and environmental risk factors associated with congenital cardiovascular malformations, describe the putative biochemical nature of the genetic predisposition relative to environmentally induced teratogenesis, and either support or discourage the use of available methods as strategies in preventing cardiovascular anomalie

ISSN:0148-7299    

DOI:10.1002/ajmg.1320280547

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractAt various gestational periods, caffeine was injected intra‐artcrially or intraperitonc‐ally into pregnant rats. The teratogenic effects of caffeine on the fetal heart were dose dependent and detectable at relatively low concentrations. The most susceptible stage was during septation of the heart. The most common cardiovascular malformation was ventricular septal defect. Extracardiovascular anomalies, such as decreased thymic weight and degeneration of the lens, were found in all fetuses; skeletal malformations were found in some fetu

ISSN:0148-7299    

DOI:10.1002/ajmg.1320280548

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractAdministration of electrical shock to the conotruncal area of embryonic chicks at developmental stage 24–27 induced a complex malformation, namely, double outlet right ventricle (DORV) of varying degrees of severity.The device used to apply electrical current to the heart was constructed using a 9‐volt battery, a push‐button switch, and a 100‐ohm potentiometer with calibrated dial. This allowed a short pulse of known voltage to be applied through the electrodes to a selected area of the heart. Two different methods were chosen to administer electrical shock at the conotruncal area of the heart. One method utilized longitudinal application of electrical shock, and the other used horizontal application of electrical shock directly to the conotruncus.Three distinct types of DORV were found in the longitudinal (L) and the horizontal (H) electrical shock groups: 1) DORV without a ventricular septal defect (VSD), in which the dilated sinus of Valsalva of the aortic valve extends into the right ventricle. 2) DORV with a subaortic VSD, with variable degrees of pulmonary stenosis and a hypoplastic left ventricle. 3) DORV with a subpulmonic VSD, pulmonic stenosis and a hypoplastic right vcentricle.Longitudinal stimulation produced a higher incidence of cardiovascular anomalies than horizontal stimulation (p = 0.01). Histological examination showed complete disappearance of myocardial fibers, myocardial degeneration, and the aggregation of protein material or glycogens within myocardial cells.Our Doppler findings demonstrate that relative to control embryos, peak velocity initially increased 3 minutes after electrical stimulation (P<0.01), and subsequently decreased significantly within 30 minutes (p<0.01). One may hypothesize that the marked initial increase of peak velocity was induced by tissue damage, which led to a narrowing of the conotruncal outflow tract. Evidence for contruncal narrowing was also reflected in percent window data (% W), which indicates the level of turbulence within a vessel. However, the decrease of peak velocity 30 minutes after stimulation might be caused by myocardial damage resulting in a diminished cardiac output. The relationship between cell death processes in the conotruncal area and DORV spectrum induced by electrical shock is di

ISSN:0148-7299    

DOI:10.1002/ajmg.1320280549

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

ISSN:0148-7299    

DOI:10.1002/ajmg.1320280503

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY