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Biomedical subjects

M A Goldman

Publications and source records attributed to M A Goldman.

At least 37 records · Page 2Linked to original sources
PubMed1986

The utilization of the human phosphoglycerate kinase gene in the investigation of X-chromosome inactivation.

The X-linked human Pgk gene has been cloned and partially characterized, and some preliminary results have been obtained regarding active vs. inactive gene comparisons of chromatin structure and methylation patterns. As yet we can say nothing definitive about what role, if any, these differences may play in X inactivation. The studies showing that DNA from the inactive X chromosome in mature somatic cells does not function in transformation of the Hprt gene strongly imply modification of the inactive X chromosome at the DNA level. However, methylation studies with the Hprt, Gd Pgk genes have revealed a complexity of methylation patterns including hypermethylation of parts of the active X gene. Resolution of just what difference is critical in expression, differentiating between cause and effect, and extrapolating to the spreading and initiation aspects of X inactivation are still, unfortunately, long-range goals. The Pgk system may be of special value in unraveling some of these difficult questions. A unique autosomal Pgk locus exists and should allow an informative comparison between an X-linked housekeeping gene and an autosomal, tissue-specific gene encoding proteins of identical enzymatic function. The proximity of Pgk to the X-inactivation control center may be useful in identifying the starting point of this very important event in early mammalian development.

Base Sequence↗
PubMed1985

Tumor of the heart diagnosed by magnetic resonance imaging.

A case of liposarcoma metastatic to the heart is presented. This is a very rare entity and only three prior case reports could be found. Magnetic resonance imaging was successfully used to visualize the tumor. These images compared favorably with a two-dimensional echocardiographic study and postmortem examination.

Echocardiography↗
PubMed1984

Replication timing of genes and middle repetitive sequences.

DNA replication in mammals is temporally bimodal. "Housekeeping" genes, which are active in all cells, replicate during the first half of the S phase of cell growth. Tissue-specific genes replicate early in those cells in which they are potentially expressed, and they usually replicate late in tissues in which they are not expressed. Replication during the first half of the S phase is, therefore, a necessary but not sufficient condition for gene transcription. A change in the replication timing of a tissue-specific gene appears to reflect the commitment of that gene to transcriptional competence or to quiescence during ontogeny. Most families of middle repetitive sequences replicate either early or late. These data are consistent with a model in which two functionally distinct genomes coexist in the nucleus.

Animals↗
PubMed1984

Left atrial size, pressure, and V wave height in patients with isolated, severe, pure mitral regurgitation.

In recent years, some concepts regarding the etiology and hemodynamics present in the syndrome of mitral regurgitation have changed. Coronary artery disease and mitral valve prolapse have replaced rheumatic heart disease as the most frequent cause of mitral regurgitation. Hemodynamic studies have shown that tall V waves in the pulmonary capillary wedge tracings are neither specific nor sensitive in detecting the presence of mitral regurgitation. In this study, we evaluated the role of various clinical, echocardiographic, and hemodynamic findings with regard to left atrial (LA) size, pressure, and V wave height. We found that the mean pulmonary capillary wedge pressure (PCW) and V wave height for the subset of patients with acute mitral regurgitation (PCW = 24.1 +/- 10.9; V = 41.2 +/- 20.7 mm Hg) was similar to the subset with chronic mitral regurgitation (PCW = 17.9 +/- 7.5; V = 32.0 +/- 18.2 mm Hg). In addition, we found that there was a significant logarithmic relationship between the LA size and the duration of the mitral regurgitation (y = 1.404 [log X] + 3.948; R = 0.678; p less than 0.0005). Lastly, we found that LA size, compliance, regurgitant volume, and regurgitant valve orifice area all increase with time.

Adult↗
PubMed1984

Aortic dilatation resulting in chronic aortic regurgitation and complicated by aortic dissection in a patient with Turner's syndrome.

A patient with XO Turner's syndrome with a 12-year history of progressive aortic root dilatation resulting in chronic aortic regurgitation is presented. Her case is unique in that it occurred in the absence of coarctation of the aorta, bicuspid aortic valve, or hypertension. Idiopathic dilatation of the aorta may be an additional risk factor to the development of aortic dissection in the setting of Turner's syndrome.

Adult↗
PubMed1984

Clinical and echocardiographic features of isolated severe pure mitral regurgitation.

Recent studies have shown that rheumatic heart disease is no longer the main cause of isolated severe pure mitral regurgitation. In this study, we evaluated various clinical and echocardiographic features found in the syndrome of mitral regurgitation. Our data is consistent with recent reports that mitral valve prolapse and coronary artery disease are now the predominant causes of mitral regurgitation and that rheumatic heart disease is a much less common etiology. In addition, our data suggest that clinical evaluation alone is usually very accurate in identifying the correct etiology. Various clinical and echocardiographic features found in the subsets of acute and chronic mitral regurgitation are described. Specifically, patients with acute mitral regurgitation were more likely to have echocardiographic evidence of segmental left ventricular dysfunction and flail mitral valve leaflet. In chronic mitral regurgitation, atrial fibrillation and left atrial dilatation were more commonly present. Echocardiography was found to be more useful in the detection of the complications of coronary artery disease rather than in identifying its presence. Patients with a New York Heart Association classification of IV and those with echocardiographic evidence of an increased left ventricular endsystolic dimension or left ventricular hypertrophy had a worse prognosis.

Adolescent↗
PubMed1984

Use of the ultrasound aspiration transducer in midtrimester amniocentesis.

Midtrimester amniocentesis was performed on 2,100 consecutive patients over a four-year period. A specially designed ultrasonic aspiration transducer was used to guide the needle into the amniotic cavity under direct vision by following the path of the needle tip ultrasonically as it entered the fluid. This technique has made the aspiration of amniotic fluid relatively simple and safe. We obtained an adequate amount of amniotic fluid in 99.2% of the patients at their initial visits. The incidence of grossly bloody taps was 0.8%, and the total number of bloody amniotic fluid specimens was 2.37%. The rate of primary culture failure was 0.53%. The total fetal loss within eight weeks after amniocentesis was 0.9% as compared with 0.52% in a control population composed of pregnant women between 16 and 24 weeks of gestation. The estimated amniocentesis-related fetal loss was 0.38%.

Amniocentesis↗
PubMed1983

Testing for hepatitis B virus in patients with chronic urticaria and angioedema.

Serologic markers of hepatitis B virus (HBV) infection were sought in serum from 85 (75%) of 114 consecutive patients with chronic urticaria and angioedema (CUA). Markers of HBV infection were detected in 15 (17.6%) patients. Of these 13 (15.3%) were found to have anti-hepatitis B surface antibody (anti-HBs) and 2 (2.4%) had hepatitis B surface antigen (HBsAg). The frequency of current and previous HBV infection is thus several times greater than that reported in the general population. No patient was found to have anti-HBs and HBsAg detectable in the same sample of blood. A diagnosis of chronic persistent hepatitis was established in the two patients with HBsAg in their circulation. The possibility that CUA was causally related to HBV infection in these two cases, as well as those with anti-HBs, was considered and it was suggested that further exploration of the relationship between CUA and HBV infection is warranted.

Adult↗
PubMed1983

Klippel-Trenaunay-Weber syndrome: appearance in utero.

We were able to detect hemihypertrophy of a fetus in a routine prenatal ultrasound examination. The presence of hemangiomas and varicose veins in the hypertrophied left lower extremity at birth enabled us to diagnose the Klippel-Trenaunay-Weber syndrome. The possibility of a congenital arteriovenous fistula causing the constellation of findings was ruled out by a nuclear flow study and a thorough physical examination. A computerized tomographic scan revealed that the hemangiomas were superficial in the hypertrophied left lower extremity and did not interrupt the deep muscle bundles.

Adult↗
PubMed1982

Somatotype and idiopathic mitral valve prolapse.

Records from 18 subjects with angiographic idiopathic mitral valve prolapse, 28 subjects with merely exaggerated posterior mitral leaflet systolic bulging, and 100 subjects with normal hemodynamic and angiographic findings were compared with regard to age, sex, height, weight, ponderal index (height/3 square root weight), auscultatory and echocardiographic abnormalities. Chest x-ray films available for subjects with mitral valve prolapse were reviewed. The ponderal index of subjects with mitral valve prolapse (13.1 +/- 0.8) differed from that of subjects with merely exaggerated posterior mitral leaflet systolic bulging (12.6 +/- 0.7) (P less than 0.02) and from that of subjects without angiographic abnormality (12.3 +/- 0.8) (P less than 0.001). The three groups differed in ponderal index when equated statistically for age, height, weight, and sex (P less than 0.001). Among mitral valve prolapse patients, an asthenic habitus occurred independent of the presence of thoracic skeletal abnormalities.

Adolescent↗
PubMed1980

Comparative karyology of the freshwater snails Bulinus tropicus and B. natalensis.

Species of the subgenus Bulinus s.s. occur in a polyploid series which is of interest because of the rarity of polyploidy in animal species and because there appears to be a relation between ploidy level and ability to transmit Schistosoma haematobium, a parasite of major public health importance. We describe a technique for the preparation of standard karyotypes using cell suspensions from colchicine-treated embryos. The results for two diploid species, B. tropicus (Krauss) and B. natalensis (Küster), are presented. Both karyotypes consist of 15 metacentric and 3 submetacentric chromosomes. However, differences in centromere position are found in four pairs of chromosomes, and in the appearance of a secondary constriction. Because B. natalensis may represent a relict taxon involved in the origin of the polyploids, the results of significance for future work on the phylogeny of this group.

Animals↗