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V R Klein

Publications and source records attributed to V R Klein.

At least 19 recordsLinked to original sources
PubMed1995

Mechanisms of the origin of a G-positive band within the secondary constriction region of human chromosome 9.

We report on a so-called rare variant where a G-positive band was sandwiched within the secondary constriction (qh) region of chromosome 9 and is apparently different from previous cases when characterized by the fluorescence in situ hybridization technique. The major differences included duplication of beta-satellite and satellite III DNA sequences and bands 9q13-->q21.1, without duplication or inversion of the alphoid sequences. Based on the reported cases, at least four types of variations can be accounted for. A variety of mechanisms have been proposed to describe the origin of a G-positive band within the 9qh region, which appears to be similar when studied by routine cytogenetic techniques but differs by molecular methods. It is hypothesized that the clinical consequences depend upon the size of the G-positive band(s) duplicated, and a genetic inactivation mechanism might have some sort of influence during the so-called heterochromatinization process. It appears that heterochromatin, once thought to be composed of junk DNA, may have some role after all in suppression of gene(s) and/or spreading of inactivation, if genes are embedded within the heterochromatic region. Apparently, the mixture of different types of DNA creating patches of genetic debris have become a fundamental hidden treasure, where genetically active chromatin could be inactivated without dire consequences. The variable nature of heterochromatin has resulted in cytogenetic heteromorphisms of a number of human chromosomes. Their characterization by molecular techniques is becoming imperative, because fetal wastage have occurred in many situations where variant chromosomes were wrongly identified as chromosomal abnormalities.

Chromosome Banding↗
PubMed1992

Fetal choroid plexus cysts: beware the smaller cyst.

Current literature suggests that amniocentesis be performed on fetuses with simple choroid plexus cysts only when such cysts are 1.0 cm or greater in diameter and bilateral. At retrospective analysis of 3,769 patients, choroid plexus cysts were noted in 87 (2.3%), representing a rate three times greater than that of previous reports. Eight-three patients underwent amniocentesis. Six (7.2%) had abnormal karyotypes. Four patients had the commonly associated chromosomal abnormality trisomy 18. Two had karyotypes not usually associated with this problem: mosaic Turner syndrome and trisomy 21. Of the six patients with abnormal karyotypes, one had a 4-mm-diameter unilateral choroid plexus cyst and three had bilateral cysts of 3-5 mm. Only one patient with a 16-mm cyst had any associated structural abnormality discovered at rigorous ultrasound examination. Karyotyping may be necessary in fetuses with small choroid plexus cysts. Deciding which patients should be encouraged to undergo amniocentesis is made more complex by these data.

Amniocentesis↗
PubMed1990

Hereditary cranium bifidum and symmetric parietal foramina are the same entity.

Cranium bifidum is literally "cleft skull." Numerous reports describe the anatomy of this defect, and crude estimates of the population prevalence suggest it is a relatively infrequent occurrence. McKusick's catalog contains only one family with cranium bifidum but several familial reports of symmetrical parietal foramina. Available information indicates that cranium bifidum and symmetrical parietal foramina are inherited in an autosomal dominant fashion and occur in orientals, blacks, whites, and native Americans. Here we report on a family with serial radiographs that document ontogenic development of parietal foramina in late childhood and adulthood from apparent cranium bifidum and parietal foramina during infancy and early childhood. We conclude that these are the same entity, differentiated only by the time during life in which the defect is demonstrated.

Cranial Sutures↗
PubMed1990

Alpha-thalassemia: prenatal diagnosis and neonatal implications.

Homozygous alpha-thalassemia major, or Bart's hemoglobinopathy, is the most common etiology of nonimmune hydrops in those of Oriental descent. The prenatal diagnosis can now be made utilizing DNA hybridization technique from fetal cells obtained by either amniocentesis or chorionic villus sampling. A case is reviewed documenting the utilization of DNA studies in managing patients known or suspected to have a history of alpha-thalassemia major.

Adult↗
PubMed1990

Effects of T's and blues abuse on pregnancy outcome and infant health status.

T's and blues (pentazocine and tripelennamine) abuse during pregnancy has been reported to be associated with adverse maternal and fetal effects. In this study, conducted at Parkland Memorial Hospital in Dallas, Texas, pregnancy outcome and health status of infants born to 23 T's and blues abusers were compared to a group of 100 unexposed women and their infants. Infants born to T's and blues abusers had significantly reduced birthweight, length, head circumference, and an increased frequency of major congenital anomalies (3 of 23), including two congenital cardiac anomalies. However, one of these cardiac anomalies occurred in the offspring of a woman who also reported moderate to heavy daily alcohol use during pregnancy. The other cardiac anomaly occurred in association with in utero anoxia. We therefore surmise that a known teratogen (alcohol) and perinatal complications caused two of the major anomalies, and not the pentazocine-tripelennamine combination per se.

Abnormalities, Drug-Induced↗
PubMed1990

Maternal and fetal effects of heroin addiction during pregnancy.

Heroin addiction during pregnancy has been reported to be associated with adverse maternal and perinatal effects. In a study of a large obstetric service in Dallas, pregnancy outcome and health status of infants born to 24 heroin addicts were compared to those in a group of 100 unexposed women and their infants. Women who used heroin during pregnancy tended to use other substances (tobacco, alcohol, cocaine) more often than did controls. The frequency of preterm birth was increased significantly in women who abused heroin during pregnancy. Sexually transmitted diseases were not increased in frequency in pregnant heroin addicts as compared to women who did not use heroin during pregnancy. Heroin addicts had infants who were significantly shorter and lighter in weight than did controls. No significant differences in head circumference or frequency of congenital anomalies were observed.

Apgar Score↗
PubMed1990

The Jarisch-Herxheimer reaction complicating syphilotherapy in pregnancy.

Thirty-three gravidas with syphilis were monitored with hourly vital signs and examinations for 24 hours after treatment with benzathine penicillin G. Fifteen (45%) of the subjects had a Jarisch-Herxheimer reaction, including all three, 12 of 20 (60%), and none of ten of those with primary, secondary, and latent syphilis, respectively. The most common symptoms were fever (73%), uterine contractions (67%), and decreased fetal movement (67%). The signs or symptoms began 2-8 hours after treatment; fevers peaked at 6-12 hours post-therapy and the events usually abated by 16-24 hours after treatment. Uterine contractions and decreased fetal activity began concurrent with maternal fever in eight of ten women reporting contractions. Transient late decelerations were detected in three of 11 monitored patients. Three of the women with Jarisch-Herxheimer reactions delivered infants with congenital syphilis, including one stillbirth, but none of those without a detectable reaction had fetal treatment failures. Prostaglandin F2 alpha and prostacyclin metabolites were elevated transiently in the one subject studied, suggesting their role in mediating the cardiovascular and uterine events in the post-treatment period. The Jarisch-Herxheimer reaction in pregnancy is similar in frequency, character, and intensity to that in nonpregnant adults, but gravidas may have increase uterine activity and transient alterations in fetal well-being. The pregnant patient with a severely affected fetus with congenital syphilis may experience preterm labor, preterm delivery, or fetal death in association with the Jarisch-Herxheimer reaction.

Adult↗
PubMed1989

Cocaine abuse during pregnancy: maternal and fetal implications.

Cocaine abuse during pregnancy has been reported to be associated with a variety of fetal complications and with preterm labor. In this cohort study, pregnancy outcome and health status of infants born to 53 cocaine abusers were compared with those of another group of 100 unexposed women and their infants. Significantly more (P less than .05) pregnancies of abusers were associated with preterm labor. In addition, significantly more (P less than .05) infants had complications at birth (ie, meconium, tachycardia). Infants born to cocaine abusers also had significantly lower (P less than .05) birth weight than infants of controls, and an excess of congenital cardiac anomalies (P less than .01).

Adult↗
PubMed1989

Familial posterior labial fusion.

Partial virilization at birth of a genotypic female resulting in varying degrees of posterior labial fusion and clitoral enlargement is most commonly due to excess androgen production from congenital adrenal hyperplasia. Rarely, labial fusion arises secondary to maternal androgen ingestion or an androgen-secreting tumor during pregnancy. We report a case of posterior labial fusion without clitorimegaly in a 12-year-old girl in which there was no evidence of androgen excess. The family history was remarkable for a similar congenital defect in two aunts and their daughters, suggesting an autosomal dominant trait with incomplete penetrance.

Child↗
PubMed1987

Kallmann syndrome associated with choanal atresia.

Kallmann syndrome is defined by the association of hypogonadotropic hypogonadism and anosmia. A previously unreported association of Kallmann syndrome and choanal atresia in a family is reported. The mechanism of the embryopathic association of hypogonadotropic hypogonadism, anosmia, and choanal atresia is though to be due to a single developmental field defect in the region of the median forebrain and associated structures. An irregular autosomal dominant mode of inheritance is suspected.

Adult↗
PubMed1987

Renal cell carcinoma in pregnancy.

A rare case of renal cell carcinoma occurring during pregnancy is described. The modalities used to make the diagnosis and the antepartum management of the patient are discussed. The case reported herein demonstrates the major diagnostic challenge of the young pregnant patient with a rare disease.

Adult↗
PubMed1986

Single-centre randomised trial of ritodrine hydrochloride for preterm labour.

106 women between 24 and 33 weeks' gestation and in preterm labour, rigidly defined to include cervical dilatation plus regular uterine contractions, were randomly allocated to receive either intravenous ritodrine hydrochloride or no tocolytic treatment. Ritodrine treatment significantly delayed delivery for 24 hours or less but did not significantly modify the ultimate perinatal consequences of preterm labour.

Adult↗
PubMed1985

Efficacy of screening for gestational diabetes.

A cost analysis of glucose screening was studied prospectively in 434 patients. All patients underwent a 50-gm oral glucose load followed by a 1-hour plasma glucose screen test at 28 weeks (+/- 2 weeks). Patients with a screen test greater than or equal to 130 mg/dl plasma glucose were further tested with an oral glucose tolerance test. Also, previously described clinical risk factors for diabetes were documented on all patients. A 3.3% prevalence of gestational diabetes was found in 178 patients with risk factors, compared with 2.4% of 256 patients without risk factors, not a significant difference. Ten of the 12 gestational diabetics were at least 24 years old, so that screening only this subgroup would still retain a good sensitivity (83%) but at half the cost of universal screening. Screening on the basis of risk factors other than age is inefficient. Though testing only patients who are 24 years of age or older is more cost effective than universal screening, an individual decision must be made regarding its reduced sensitivity.

Adult↗
PubMed1985

Cost-effective criteria for glucose screening.

To study cost-effective screening criteria for gestational diabetes, a prospective study of 1012 patients was completed. All patients underwent a glucose screen between 26 and 30 weeks of gestation, consisting of a 50-g oral glucose load followed by a one-hour plasma glucose determination. Patients with a glucose screen greater than or equal to 130 mg/dL were studied with a standard three-hour oral glucose tolerance test. The incidence of gestational diabetes was 2.4% (24 of 1012). Only one gestational diabetic was identified with a glucose screen below 150 mg/dL. Twenty-two of the 24 cases were at least 24 years old. Twenty-one of the 24 (88%) gestational diabetes had a glucose screen greater than or equal to 150 mg/dL and were 24 years old or greater. The cost of the diagnosis in these latter patients was 40% of the cost of diagnosis of universal screening with a threshold of 130 mg/dL. It is concluded that screening with a threshold of 150 mg/dL only patients who are at least 24 years old should be considered an alternative to universal screening.

Adult↗