Search PubMed⌕ Search

Biomedical subjects

D L Levy

Publications and source records attributed to D L Levy.

At least 19 recordsLinked to original sources
PubMed1992

Gene expression in mental illness: a navigation chart to future progress.

An initial course in disentangling complex causal interactions in psychiatric illnesses, we suggest, is finding co-familial traits with classical Mendelian segregation. Starting with non-Mendelian traits, three methods can be used to find underlying Mendelian phenotypes. (1) Statistically-inferred latent traits, with more nearly Mendelian transmission than the measures from which they are derived, can serve as pointers to concrete Mendelian phenotypes. (2) Linkage of non-Mendelian traits to genetic markers, if it can be established, can be followed by searching for phenotypes that discriminate carriers from non-carriers of the imputed trait gene. (3) In the long run, the most successful method is likely to be direct refinement of non-Mendelian behavioral and physiological traits into more fundamental components.

Bipolar Disorder↗
PubMed1992

Normal eye tracking is associated with abnormal morphology of medial temporal lobe structures in schizophrenia.

Eye tracking and brain morphology assessed by magnetic resonance imaging were examined in 48 patients in their first episode of schizophrenia and in 15 normal controls. Schizophrenic patients showed higher rates of eye tracking dysfunction and more abnormal brain morphology involving the lateral ventricles, medial temporal lobe (MTL) structures and the frontal-parietal cortex than controls. Enlargement of the lateral ventricles and global rating of abnormal brain morphology were significantly more prevalent in male schizophrenics than female schizophrenics. These findings indicate that abnormalities in a variety of brain regions are present in some schizophrenics during the period shortly after the first hospitalization and could not be a function of treatment or chronic illness. We found no relation between abnormal eye tracking and any single feature of abnormal brain morphology. However, normal eye tracking was significantly associated with MTL abnormalities in schizophrenics, reflecting an inverse association between quality of eye tracking and degree of abnormality in MTL structures. These results suggest that abnormal eye tracking is not mediated by the same processes that lead to structural brain anomalies in schizophrenia.

Adolescent↗
PubMed1991

Value of a random single Doppler study of the umbilical artery for predicting perinatal outcome.

A prospective blinded study was performed on 191 high-risk patients with pregnancies ranging from 25 to 42 weeks gestation to investigate the value of a single Doppler analysis of the umbilical artery blood flow waveform (systolic-to-diastolic ratio, S/D) for predicting poor perinatal outcome. This was defined as the presence of heavy meconium, delivery of a growth-retarded infant, an umbilical cord arterial pH less than 7.2, or a 5-minute Apgar score less than 7. The interval between Doppler examination and delivery ranged from 12 hours to 15 weeks. No clinical data were available to the examiner performing the Doppler study. Moreover, the Doppler measurements were unknown to the attending physicians. The sensitivity, specificity, and positive and negative predictive values of the Doppler study in predicting outcome were 30.4%, 92.9%, 36.8%, and 92.6%, respectively, with an adverse outcome prevalence of 12%. These results indicate that a single random S/D ratio from the umbilical artery is not an adequate screening test for the risk of perinatal complications.

Female↗
PubMed1990

Placental histology in fetuses between 18 and 23 weeks' gestation with abnormal karyotype.

Placentas from karyotypically abnormal fetuses (18 to 23 weeks' gestation) were analyzed prospectively at the light microscopic level. Group I consisted of 14 control placentas. Group II consisted of 14 placentas from fetuses with an abnormal karyotype. Secondary and tertiary stem villi counts, small muscular artery counts, and total vessel counts were determined per 100 x field. There were no differences in secondary and tertiary stem villi counts between groups. A significant decrease in small muscular artery counts (p less than 0.01) and total vessel counts (p less than 0.01) was noted in group II. Placental and fetal weights were comparable between groups. This undervascularization may represent placental immaturity as a result of arrested or delayed angiopoiesis. It appears that this abnormality is established before the third trimester and may be enhanced by late vascular obliteration as reported by others. These data substantiate the concept that the structure and function of the placenta is determined to a great degree by fetal karyotype and may help explain the morbidity and mortality seen in these fetuses.

Chorionic Villi↗
PubMed1989

Congenital cystic hygroma of the neck diagnosed prenatally: outcome with normal and abnormal karyotype.

Twenty-two cases of cystic hygromas were diagnosed prenatally at Eastern Virginia Medical School and followed through the neonatal period. Our series was combined with 131 cases which have been described in the literature. Karyotypes were obtained in 110 fetuses and 80 (72.7 per cent) were abnormal. Fifty-one were not terminated: 30 with abnormal and 21 with normal karyotypes. There were no neonatal survivors in the group with abnormal karyotypes. There were five survivors in the 21 with normal karyotypes but only 2/21 without severe medical complications. Combining our series with those previously reported in the literature would suggest only a 2-3 per cent rate of intact survivors when fetal cystic hygromas are diagnosed in utero. This information should be helpful when counselling patients whose pregnancies carry this diagnosis.

Amniotic Fluid↗
PubMed1989

Doppler study of umbilical artery blood flow waveform. Should we use an instrument-adapted nomogram?

Doppler studies of umbilical artery blood flow waveform are becoming an accepted tool of antenatal estimation of fetal well-being. The S/D ratio of the systolic peak (S) to the end-diastolic (D) frequency is the most commonly used parameter. Nomograms relating S/D ratio to gestational age have been published both for normal and pathologic pregnancies. Three hundred twelve analyses of umbilical artery blood flow were performed by continuous Doppler technology in normal, well-dated pregnancies using either one of the following instruments: GE 3600 (GE) or Multigon 500A (MG). Both instruments showed a decrease of S/D with GA, but, by use of a nonpaired t test, a statistically significant difference was found between the two machines. Data on the system used for a particular study should be provided; nomograms for this particular instrument should be consulted and the same machine should be employed for repeat testing in longitudinal studies.

Blood Flow Velocity↗
PubMed1989

Doppler analysis of the umbilical artery. The importance of choosing the placental end of the cord.

Thirty normal pregnancies were studied with continuous or pulsed Doppler ultrasound (50 measurements). The ratio of systolic (S) to end-diastolic (D) measurement, or S/D ratio, was obtained at both ends of the cord: the placental insertion and the fetal abdominal insertion. A statistically significant difference was demonstrated between the two sets of measurements. Normal values were obtained at the placental insertion, whereas, simultaneously, the fetal abdominal insertion generated highly abnormal values. When performing Doppler waveform analysis of the umbilical artery, if abnormal values are obtained, one should be cautious to be certain that they originated from the placental insertion.

Blood Flow Velocity↗
PubMed1989

Perceived aluminum-related disease in a dialysis population. A report from the End-Stage Renal Disease Network 28.

A survey to assess the perceived prevalence of aluminum-related disease was conducted by the Medical Review Board of the End-Stage Renal Disease Network 28 from 1986 to 1987. Responses were obtained for 855 of 3000 patients on dialysis representing 17 of 39 participating dialysis units within the network. Almost 40% of the patients surveyed had been receiving dialysis therapy for over 3 years. Patients on hemodialysis (83% of the study group) had the water used to prepare the dialysate pretreated. Serum aluminum determinations were obtained in 240 (28%) of the 855 patients; other methods of assessing body aluminum burden were performed in less than 10% of the survey population. When obtained, elevated serum aluminum measurements were more likely to be found with each year patients were given dialysis and with each year patients were treated with oral aluminum gels. With the exception of patients with bone pain, clinical signs and symptoms did not correlate with elevated serum aluminum. However, the prevalence of muscle weakness, bone pain, fractures, and dementia in the survey group did correlate with years on dialysis and/or years receiving oral aluminum gels. Data gathered from this survey are consistent with the view that signs and symptoms suggestive of an increased body aluminum burden occur in the minority of patients on dialysis. Nevertheless, patients at risk for aluminum intoxication (years on dialysis, years receiving gels, patients with clinical signs) may not be adequately identified.

Aluminum↗
PubMed1988

A single dominant gene can account for eye tracking dysfunctions and schizophrenia in offspring of discordant twins.

Eye movement dysfunctions (EMDs), detectable during smooth pursuit, occur in a majority of schizophrenics and in 45% of their first-degree relatives. Previous data suggest that they represent a biologic marker for schizophrenia. To determine the mode of transmission of the schizophrenia-EMD complex, the eye movements of offspring of monozygotic and dizygotic twins were recorded. One group of twins was discordant for schizophrenia; the other group for manic depression or reactive psychosis. The data suggest that EMDs and at least some schizophrenias can be considered expressions of a single underlying trait that is transmitted by an autosomal dominant gene.

Affective Disorders, Psychotic↗
PubMed1988

Lower limb movements and urologic function in fetuses with neural tube and other central nervous system defects.

Lower limb movements and urologic systems were evaluated by prenatal ultrasound in 120 fetuses with either neural tube defects or intracranial anomalies. Despite anticipated major lower extremity and bladder dysfunction, lower limb movements were seen in 100% of the fetuses with anencephaly and encephaloceles, 93% with isolated spina bifida, 60% with complex spina bifida and 90% with abnormal intracranial findings. In all the cases except those with cloacal exstrophy, fetal bladder and collecting systems appeared normal. Therefore, fetal lower limb movements and urinary tract integrity appear to have no diagnostic or prognostic value in fetuses with neural tube defects or other central nervous system anomalies. These diagnoses can only be made by direct ultrasound observation of the lesion itself.

Anencephaly↗
PubMed1987

Fetal sacrococcygeal teratoma.

Early prenatal diagnosis of fetal sacrococcygeal teratoma (SCT) has enabled the perinatal team to institute management of this condition during the perinatal period. We report 2 additional cases to our previous 27 cases including 1 which represents the earliest diagnosis of SCT. Fetal SCT behaves in a different manner than neonatal SCT. In utero manipulation of fetal SCT may be possible if diagnosis is made during the second trimester.

Adult↗
PubMed1986

An analysis of the obstetric outcome of 125 consecutive pregnancies conceived in vitro and resulting in 100 deliveries.

One hundred twenty-five consecutive pregnancies conceived in vitro resulted in 100 deliveries of 115 babies. There were 23 clinical abortions (18.4%) and two tubal pregnancies. During the same interval 30 preclinical pregnancies occurred, but these pregnancies did not progress. There were 26 multiple pregnancies (37.1%) before the twelfth week; these reduced spontaneously to 14 (22.2%) multiple births at delivery. Eight infants were delivered prematurely, and three of these died. Three babies had some congenital abnormality. Vaginal bleeding occurred during pregnancy in 59% of patients. Cesarean section was the method of delivery in 56% of patients. Other complications of pregnancy were similar to those of comparable populations.

Abortion, Spontaneous↗
PubMed1985

Pharmacologic evidence for specificity of pursuit dysfunction to schizophrenia. Lithium carbonate associated with abnormal pursuit.

Conflicting findings regarding the prevalence of abnormal smooth-pursuit eye movements in patients with major affective disorders call into question the specificity of impaired smooth-pursuit eye movements to schizophrenia. We report that pursuit is impaired in 88% of lithium carbonate-treated affective disorder patients whose pursuit was normal prior to receiving this drug. Over half of lithium carbonate-treated affective disorder patients in remission also showed impairment of smooth-pursuit eye movements. In conjunction with recent prevalence data on family members of psychiatric patients, the findings support the specificity of abnormal pursuit as a biological trait associated with schizophrenia, but not with the major affective disorders. The mechanisms by which lithium carbonate impairs pursuit are discussed.

Adult↗
PubMed1985

Oral ritodrine and preterm premature rupture of membranes.

A prospective randomized study was performed to determine whether or not oral ritodrine therapy significantly prolonged the latent period in patients with prematurely ruptured membranes. Compared with a control group of similar patients, those treated had a significantly prolonged mean latent period. In addition, 47.6% of the treatment group versus 14.2% of the control group had a latent period of more than one week.

Birth Weight↗