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Biomedical subjects

M F Schwartz

Publications and source records attributed to M F Schwartz.

At least 19 recordsLinked to original sources
PubMed1991

De novo 13q partial duplication identified by cytogenetic, biochemical and molecular approaches.

A 3.5-month-old female infant manifesting dysmorphic facies, developmental delay and failure to thrive was referred for cytogenetic evaluation. Peripheral lymphocytes revealed three chromosomally distinct cell lines: 46,XX/46,XX,10p+/47,XX,10p+,+mar. Dermal fibroblasts revealed only the 46,XX,10p+cell line. High resolution G-, R-, and Q-banding suggested that the extra chromosomal material (10p+) represented a duplication of the segment 13q14----13qter. Parental karyotypes were normal. As absolute identification of de novo chromosomal abnormalities, based solely on cytogenetic studies, is sometimes difficult, both biochemical and molecular approaches were undertaken to elucidate this abnormality in more detail. Dosage effects were examined using esterase D (localized to 13q14.1) and the DNA probes p1E8 and p9A7 (localized to 13q22 and 13q31/32, respectively). These studies suggested the presence of only 2 copies of esterase D, but 3 copies of both DNA probes, allowing identification of the breakpoint at 13q14.2.

Abnormalities, Multiple↗
PubMed1990

Substitution of arginine for glycine at position 847 in the triple-helical domain of the alpha 1 (I) chain of type I collagen produces lethal osteogenesis imperfecta. Molecules that contain one or two abnormal chains differ in stability and secretion.

Dermal fibroblasts from a fetus with perinatal lethal OI synthesized normal and abnormal type I procollagen molecules. The abnormal molecules contained one or two pro alpha 1 (I) chains in which glycine at position 847 in the triple helical region was substituted by arginine as the result of a de novo G-to-A transition in the first base of the glycine codon. The substitution resulted in increased posttranslational modification amino-terminal of the mutation site of all chains in molecules that contained one or more abnormal chains. Secretion of the overmodified molecules was impaired, and intracellular retention of molecules which contained two abnormal chains was greater than that of molecules which contained one abnormal chain. The thermal stability of molecules that contained two abnormal chains was markedly lower than that of molecules containing one abnormal chain. After cleavage of molecules with vertebrate collagenase, the thermal stability of the overmodified A fragments was greater than that of the normal molecules. Our findings indicate that the cell distinguishes three classes of molecules and suggest that these molecules differ depending on the number of abnormal chains in the trimer.

Amino Acid Sequence↗
PubMed1989

Prenatal detection of trisomy 9 mosaicism.

Chromosomal mosaicism in amniotic fluid cells poses a serious dilemma in prenatal diagnosis since the observation may represent: (1) pseudomosaicism--an inconsequential tissue culture artefact; or (2) true mosaicism--occurring in approximately 0.20 per cent of amniocenteses with a significant impact on pregnancy outcome. Mosaicism for trisomy 9 was observed in an amniotic fluid specimen obtained for advanced maternal age with two cell lines [46,XX (46 per cent)/47,XX, +9 (54 per cent)] present in each of four culture flasks. Since more than 75 per cent of newborns with trisomy 9 mosaicism have complex cardiac malformations, a fetal echocardiogram was obtained at 20 weeks' gestation and interpreted as normal. A fetal blood sample (22 weeks' gestation) disclosed only a single trisomy 9 cell among the 100 metaphases analysed. However, a second fetal echocardiogram performed at the time of blood sampling suggested a non-specific cardiac anomaly. Fetal autopsy following elective pregnancy termination revealed several malformations including severe micrognathia, persistence of the left superior vena cava, and skeletal anomalies. Cytogenetic studies of cell cultures derived from several fetal tissues demonstrated trisomy 9 ranging from 12 to 24 per cent.

Abnormalities, Multiple↗
PubMed1989

The quantitative analysis of agrammatic production: procedure and data.

Despite the long-standing interest in structural aspects of aphasic production, no method has emerged for the systematic analysis of aphasic speech. This paper attempts to address that need by outlining a procedure for the quantitative assessment of narrative speech which yields measures for both morphological and structural characteristics of aphasic production. In addition to complete instructions for carrying out this analysis, data for three groups of subjects are presented: agrammatic aphasics, aphasics who are similarly nonfluent but not clinically judged as agrammatic, and normal controls. While the agrammatics were distinguishable from the nonagrammatic patients on most measures, both nonfluent groups showed comparable reductions in the structural complexity of their propositional utterances. Other findings include indications from individual patient data that aspects of grammatical morphology may dissociate in agrammatism.

Adult↗
PubMed1989

Antenatal detection of cystic hygroma.

Ultrasonographic evaluation, as a routine component of prenatal care, has significantly contributed to in utero assessment of pregnancy status. The detection of fetal abnormalities by ultrasound, however, has raised clinical questions and created parental dilemmas concerning the outcomes of such pregnancies. A relatively frequent anomaly observed on routine ultrasonographic examination is the posterior nuchal cystic hygroma. We report the prenatal detection of 16 cases of cystic hygromata and an analysis of a survey of the world's literature including an additional 155 cases. The information available from these 171 cases allows a clearer picture of the prognosis for fetuses in whom posterior cystic hygroma is detected in utero. Regarding outcome, 73.2 per cent of cases were terminated at the parents' request; 37 cases (22.6 per cent) resulted in fetal death in utero prior to any intervention. Only 7 per cent of continuing pregnancies resulted in live-born infants. Of the 142 cases with available cytogenetic findings, 22 per cent had normal karyotypes; 58 per cent had a karyotype associated with Turner syndrome phenotype; while autosomal trisomies and various structural abnormalities made up the remaining 20 per cent. Even among those fetuses with normal chromosomes, various physical anomalies were detected. Fetal hydrops was present in 66 per cent of the 102 cases with pertinent information. For those fetuses demonstrating cystic hygroma and normal karyotypes, Mendelian syndromes must be considered in the differential diagnosis. Alpha-fetoprotein evaluation of both maternal serum and amniotic fluid was not helpful in determining prognosis of these fetuses. The ultrasonographic finding of a posterior nuchal cystic hygroma, with or without accompanying fetal hydrops, is a valid indicator for a poor outcome of such pregnancies.

Adult↗
PubMed1988

Ulerythema ophryogenes with multiple congenital anomalies.

Ulerythema ophryogenes, a rare dermatologic disorder characterized by inflammatory keratotic facial papules that may result in scars, atrophy, and alopecia, can occur in association with other congenital anomalies. A case reported here was accompanied by an unusual facies, developmental delay, central nervous system abnormalities, dental anomalies, and undescended testes. There was no response of the cutaneous lesions to topical keratolytics, topical tretinoin, or a short course of oral isotretinoin.

Abnormalities, Multiple↗
PubMed1988

Dysplastic cardiac development presenting as cardiomyopathy.

Multiple manifestations of disordered or arrested cardiac muscle development are reported in a 14-year-old boy with clinical evidence of heart disease. These include persistent noncommunicating intramyocardial sinusoids, anomalous right ventricular muscle bands, muscular deficiency of ventricular septum, and papillary muscle underdevelopment. To our knowledge, this complex of findings has not been previously described.

Adolescent↗
PubMed1986

Reconstructing from a degraded trace: a study of sentence repetition in agrammatism.

Six agrammatic aphasics repeated simple active and passive voice sentences, varying in degree of semantic constraint: plausible, reversible, and implausible. Frequency of correct response was not sensitive to this semantic manipulation, but error pattern was. In general, errors to plausible targets consisted of relatively inconsequential transformation of the open or closed class vocabulary, while errors to implausible targets implicated a change of syntactic voice. In making these errors, the patients displayed evidence of productive control of the passive morphology and a degree of sensitivity to the syntactic and thematic consequences consequences of passive voice. The repetition errors did not transform the surface order of the major lexical items. The results are interpreted as evidence for a sentence memory trace that preserves, minimally, the major grammatical roles of the target sentence and that serves as input to a reconstructive process that is biased toward the production of semantically plausible sentences.

Adult↗
PubMed1986

Echocardiographic abnormalities and disease severity in Fabry's disease.

Fabry's disease is an X-linked recessive genetic deficiency of the enzyme alpha-galactosidase A, which leads to the pathologic deposition of neutral glycosphingolipids in lysosomes of the vascular endothelium of the heart, brain and kidney. The disease is progressive in hemizygous male patients, with increasing involvement of the major organs leading to death. Because cardiac involvement is a constant feature, echocardiograms were performed on 35 patients with Fabry's disease, 23 hemizygotes (aged 28.6 +/- 14 years) and 12 heterozygotes (aged 31.6 +/- 6 years), to determine whether cardiac involvement could be detected noninvasively. The results demonstrated that hemizygous male patients had a greater aortic root diameter, thicker interventricular septum and greater ventricular mass than did heterozygous female patients. Left ventricular mass per square meter of body surface area correlated well with clinical disease severity (r = 0.68, p less than 0.05), suggesting progressive glycosphingolipid deposition. Older heterozygotes (greater than 25 years old) had more severe evidence of cardiac disease than did younger male patients. Although mitral valve prolapse was identified in 12 (54%) of 23 male hemizygotes and in 7 (58%) of 12 female heterozygotes its presence did not correlate with clinical disease severity or other echocardiographic variables. Therefore, echocardiographic evidence of Fabry's disease appears to correlate with age-related disease severity and may be a useful noninvasive marker to follow disease progression and possible regression when appropriate therapy becomes available.

Adult↗
PubMed1986

Inherited X-chromosome inverted tandem duplication in a male traced to a grandparental mitotic error.

A male infant was referred for cytogenetic evaluation because of dysmorphic features and developmental delay. In both lymphocytes and skin fibroblasts, a modal number of 46 chromosomes was obtained with an obvious elongation of the long arm of the X chromosome (Xq+). Studies of seven members in 3 generations of this family showed that the proband's mother, sister, and maternal grandmother were phenotypically normal carriers of this abnormal X chromosome. High resolution GTG- and RBG-banding defined the extra chromatin material as an inverted duplication of Xq21----Xq24. This was supported by an approximate twofold increase in alpha-galactosidase A activity, localized to Xq21----q24, observed in the proband's lymphocytes and fibroblasts. BrdU-incorporation studies of the mother's lymphocytes showed the abnormal X to be late replicating in all 100 cells studied and normal alpha-galactosidase A levels. Cytogenetic analysis of the maternal grandmother revealed cytogenetic mosaicism with one cell line containing the abnormal X (37%), and the other, a normal female karyotype (63%). This family is instructive since: (1) it represents only the second case of a dysmorphic male demonstrating a confirmed interstitial partial Xq duplication, and (2) the origin of this familial structural rearrangement has been traced to a grandparental mitotic error.

Adult↗
PubMed1985

Acute intraoperative choroidal effusion.

We studied five cases of acute choroidal effusion that occurred during intraocular surgery and one case of a localized choroidal hemorrhage. Acute intraoperative choroidal effusion is a poorly recognized surgical complication and may precede expulsive hemorrhage in many cases. The treatment is immediate closure of the wound, after which the intraocular pressure may rise to 80 mm Hg or more. However, the pressure will return to normal after 15 to 30 minutes and the area of effusion will remain localized. Scleral puncture to drain fluid is not indicated if the wound can be closed before there is a prolapse of the iris or other intraocular tissues.

Acute Disease↗
PubMed1977

Hypomelanosis of Ito (incontinentia pigmenti achromians): a neurocutaneous syndrome.

Hypomelanosis of Ito (incontinentia pigment achromians, systematized achromic nevus) is a cutaneous abnormality consisting of bizarre, patterned, macular hypopigmentation over variable portions of the body surface. Multiple associated defects in other systems occur in a significant precentage of affected individuals. Most commonly, the central nervous system, eye, and musculoskeletal structures are involved. It is suggested that the cutaneous abnormality, which is often detectable at birth or during infancy, may forewarn pediatricians of the possible emergence of defects in other organ systems.

Abnormalities, Multiple↗