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Biomedical subjects

M Berant

Publications and source records attributed to M Berant.

At least 55 records · Page 3Linked to original sources
PubMed1996

Percutaneous closure of small patent ductus arteriosus: comparison of Rashkind double-umbrella device and occluding spring coils.

We compared our current practice of closing small patent ductus arteriosus (PDA) with coils with our previous experience of using double-umbrellas. Twelve patients underwent percutaneous closure of a small PDA with a coil. Selection criteria were a minimal diameter of < or = 2.5 mm and angiographic type A or E. The 12 most recent, non-consecutive patients who had undergone double-umbrella device closure of a PDA and would presently be considered suitable candidates for spring coil occlusion were retrospectively reviewed. The two groups were compared with regard to complications and immediate and midterm results. Eleven of the 12 attempted PDA occlusions using spring coils were successful. The mean follow-up period was 5.8 +/- 4.6 months. Color-Doppler echocardiograms have shown no residual leaks, no turbulence in the descending aorta, and no left pulmonary artery stenosis. All 12 attempted double-umbrella device placements were successful. The mean follow-up period was 16.2 +/- 5.8 months. Color-Doppler echocardiograms have shown trivial residual leaks in four patients and mild turbulent flow in the left pulmonary artery in one patient. There was no significant difference between the two groups in demographic and hemodynamic data. Although the mean follow-up time was significantly longer in the patients who underwent double-umbrella closure, there was significantly more color-Doppler echocardiographic evidence of residual flow (P < 0.03). Small PDA closure with coils is effective, resulting in less residual leaks compared with the double-umbrella device.

Child↗
PubMed1995

Reduced cellular cholesterol content in peroxisome-deficient fibroblasts is associated with impaired uptake of the patient's low density lipoprotein and with reduced cholesterol synthesis.

Mammalian cells acquire cellular cholesterol by de novo synthesis as well as by uptake of low density lipoprotein (LDL). Peroxisomes contain enzymes involved in the synthesis of cholesterol, and peroxisome-deficient (PD) patients have been shown to have hypocholesterolemia and abnormal LDL. We therefore decided to study whether cholesterol synthesis and cellular uptake of LDL are impaired in cultured PD fibroblasts. The present study demonstrates a significantly lower cellular cholesterol mass in fibroblasts from three PD patients, as compared to control cells (41-59% of controls). The rate of cholesterol synthesis was also reduced in all three PD cell lines, being 16-20% of the control values. LDL binding and degradation by fibroblasts were 3- to 5-fold higher in the PD cells as compared to control cells. Similarly, enrichment of normal fibroblasts with tetracosanoic acid (C-24:0), a situation that could mimic the in vivo accumulation of very long chain fatty acid (VLCFA) in PD cells, caused LDL binding and degradation to be 4-fold higher than in non-treated cells. On the other hand, the uptake of LDL derived from PD patients by normal fibroblasts was markedly reduced (by up to 67%) in comparison to the cellular uptake of normal LDL. Similar results were obtained in PD cells. This study demonstrates a lower cellular cholesterol content and reduced cholesterol synthesis rate in PD cell lines. In addition, we demonstrate that regulation of the uptake of normal LDL by cellular LDL receptors is operative in PD cells, whereas LDL derived from PD patients is not recognized normally by the LDL receptor.(ABSTRACT TRUNCATED AT 250 WORDS)

Cholesterol↗
PubMed1994

Further studies on erythrocyte thiamin transport and phosphorylation in seven patients with thiamin-responsive megaloblastic anaemia.

Erythrocyte thiamin metabolism and transport were investigated in 7 patients from Brazil, Israel and Italy suffering from thiamin-responsive megaloblastic anaemia (TRMA) associated with diabetes mellitus and sensorineural deafness. All patients discontinued thiamin therapy for 4-7 days before the investigation. TRMA patients showed invariably reduced total thiamin levels in erythrocytes (percentage reduction compared with healthy controls, -46.8 +/- 3%; mean +/- SEM). The proportions of individual thiamin compounds, expressed as a percentage of total thiamin content, were within the normal range, whereas their absolute amounts were significantly decreased in the following order: thiamin monophosphate > thiamin pyrophosphate > thiamin. Thiamin pyrophosphokinase activity was also reduced as compared with controls (mean reduction +/- SEM, -25.9 +/- 1%). The saturable, specific component of thiamin uptake, which normally prevails at physiological concentrations of thiamin (< 2 mumol/L), was absent in erythrocytes obtained from TRMA patients, while the non-saturable (diffusive) component of uptake was normally present. These results confirm observations made previously in two patients and demonstrate that TRMA is consistently associated with a state of thiamin deficiency, which is presumably secondary to reduced thiamin cellular transport and absorption (caused by lack of a membrane-specific carrier), and to impaired intracellular pyrophosphorylation.

Anemia, Megaloblastic↗
PubMed1994

A new type of peroxisomal disorder with variable expression in liver and fibroblasts.

We describe two siblings, presently 5 and 9 years of age, who had neurodegenerative symptoms after the first year of life. Although they lacked clinical characteristics of a peroxisomal disorder, they had elevated levels of plasma very long chain fatty acids, pipecolic and phytanic acids, and abnormal bile acid intermediates, which suggested a generalized peroxisome deficiency disorder. Immunocytochemical study and electron microscopy of the liver disclosed absence of peroxisomes in approximately 90% of hepatocytes. However, the remaining 10% of the hepatocytes had numerous normal-looking peroxisomes containing catalase activity and catalase antigen. Alanine glyoxylate aminotransferase and the peroxisomal beta-oxidation enzymes acyl-coenzyme A oxidase and 3-ketoacyl coenzyme A thiolase were also present in the organelles. Both cell types were grouped in clusters. In contrast to most of the liver cells, fibroblasts cultured from skin biopsy specimens had normal peroxisomal functions. Thus this defect in peroxisome biogenesis is characterized by variable expression in different tissues (liver vs fibroblasts), as well as within individual cells in the same tissue (liver mosaicism). Awareness of the heterogeneity in tissue expression of peroxisomal disorders could be of critical importance in prenatal diagnosis.

Child↗
PubMed1994

Total cavopulmonary connection (TCPC) for complicated congenital heart malformations.

We reviewed our experience with 40 patients who had undergone total cavopulmonary connection (TCPC) during the past three years. Thirty-one patients had functional single ventricle; only 8 of these with tricuspid atresia, five patients had complex forms of double outlet right ventricle (DORV), and four complex A-V canal. Previous palliative procedures, mostly systemic-pulmonic shunts, were performed in 34 patients. Concomitant procedures were required in 18 patients, mainly reconstruction of distorted pulmonary arteries. A subgroup of 14 high risk patients, that did not fulfil the classical Fontan criteria, underwent 4 mm fenestration of the intra-atrial baffle. There were three (7.5%) early postoperative deaths which occurred in the higher risk group (fenestrated group). However, the remaining patients were all in functional class I or II. Total cavopulmonary connection provides reasonably good definitive palliation for patients with single ventricle physiology. Fenestration of the intra-atrial baffle increases the number of candidates suitable for the Fontan procedure, although the exact inclusion criteria for these patients has yet to be defined.

Adolescent↗
PubMed1994

Total cavopulmonary connection for complicated congenital heart malformations.

We reviewed our experience with 40 patients who had undergone total cavopulmonary connection during the past 3 years. Thirty-one patients had functional single ventricle, only 8 with tricuspid atresia; five had complex forms of double outlet right ventricle, and 4 complex A-V canal. Previous palliative procedures, mostly systemic-pulmonic shunts, were performed in 34 patients. Concomitant procedures, mainly reconstruction of distorted pulmonary arteries, were required in 18 patients. A subgroup of 14 high risk patients, who did not fulfil the classical Fontan criteria, underwent 4 mm fenestration of the intraatrial baffle. There were 3 (7.5%) early post-operative deaths that occurred in the higher risk group (fenestrated group). However, the remaining patients were all in functional class I or II. Total cavopulmonary connection provides reasonably good definitive palliation for patients with single ventricle physiology. Fenestration of the intraatrial baffle increases the number of candidates suitable for the Fontan procedure, although the exact inclusion criteria for these patients has yet to be defined.

Adolescent↗
PubMed1993

Congenital muscular dystrophy with neurological abnormalities: association with Hirschsprung disease.

We report on a baby girl with congenital muscular dystrophy (CMD) with neurological abnormalities ("CMD Plus" condition), who also had Hirschsprung disease. This association may indicate a category of congenital muscular dystrophy with involvement of the visceral nervous system. We propose that Hirschsprung disease be added to the list of anomalies pertaining to the "CMD Plus" array, and that CMD should be considered when Hirschsprung disease occurs with central nervous system anomalies.

Brain↗
PubMed1993

[Fanconi anemia syndrome as a predisposing factor for acquired bone marrow aplasia].

A 4-year old girl who received prophylactic therapy with oral cephalexin for 1 year because of a history of urinary tract infections, was referred for evaluation of short stature. On physical examination mildly dysmorphic features were observed. Blood counts disclosed pancytopenia, and bone marrow examination showed hypoplasia of all 3 cell lines. Chromosome analysis after exposure to a DNA cross-linking agent (diepoxybutane) showed a chromosomal breakage pattern consistent with Fanconi anemia. Discontinuation of cephalexin was followed by improvement in hematological values. This course of events supports the hypothesis that acquired bone marrow depression may be a manifestation of Fanconi anemia, warranting the appropriate diagnostic work up in every case of acquired bone marrow aplasia.

Bone Marrow Diseases↗
PubMed1993

Congenital juvenile chronic myelogenous leukemia: therapeutic trial with interferon alpha-2.

A newborn with congenital juvenile chronic myelogenous leukemia (JCML) is described. The diagnosis was suggested by the characteristic clinical and hematologic presentation, and was confirmed by the results of in-vitro cultures of the hematopoietic progenitors, which showed excessive proliferation of monocytic colonies, with and without the addition of exogenous granulocyte-macrophage colony stimulating factor (GM-CSF). Based on published in-vitro response of JCML cells to alpha interferon-2 (alpha IFN 2), we treated this child for 17 weeks with subcutaneous alpha interferon, 1,000,000 units per day. In contrast to previous in vitro results, treatment of this patient affected neither the clinical course of the disease, nor the in vitro growth of the peripheral blood-derived monocytic colonies.

Colony-Forming Units Assay↗
PubMed1993

The value of polyclonal carcinoembryonic antigen immunostaining in the diagnosis of microvillous inclusion disease.

Microvillous inclusion disease is a specific disorder recognized as a cause of intractable diarrhea of infancy. We studied three cases by light microscopy, electron microscopy, and immunostaining for polyclonal carcinoembryonic antigen (CEA). Histologically, all cases had villous atrophy and abnormal accumulation of periodic acid-Schiff-positive material in surface enterocytes. Ultrastructurally, poorly developed brush-border and intracytoplasmic inclusions lined by intact microvilli were present in surface enterocytes. Crypt cells showed well-preserved surface microvilli. Carcinoembryonic antigen immunostaining showed prominent intracytoplasmic reactivity in surface enterocytes and linear brush-border reactivity in crypt cells. Normal and diseased small bowel biopsy specimens used as controls revealed linear brush-border reactivity without intracytoplasmic staining. Intracytoplasmic positivity for carcinoembryonic antigen in microvillous inclusion disease is explained by its presence in the glycocalyx within the microvillous inclusions. The demonstration of a distinct staining pattern for polyclonal carcinoembryonic antigen in routinely processed small bowel biopsy specimens provides a new useful criterion that complements other established techniques for accurate diagnosis of microvillous inclusion disease.

Antibodies↗
PubMed1993

Antibiotic treatment of experimental Pseudomonas aeruginosa pneumonia in guinea pigs: comparison of aerosol and systemic administration.

Pseudomonas aeruginosa pneumonia is associated with high mortality despite appropriate systemic antibacterial therapy. To examine the effects of aerosolized tobramycin on experimental P. aeruginosa pneumonia, guinea pigs were assigned to two main groups: a study group, in which P. aeruginosa was instilled into the tracheal lumen, and a control group, in which normal saline was instilled. Each group was then subdivided according to treatment: normal saline or tobramycin by intramuscular injection, normal saline or tobramycin by aerosol, or normal saline or tobramycin via both aerosol and intramuscular injection. Compared with either intramuscular or aerosolized tobramycin, the combination of aerosol plus intramuscular tobramycin achieved slightly higher survival, total eradication of P. aeruginosa from lungs, and a significant further reduction of lung inflammatory changes. Adding aerosolized tobramycin to systemic tobramycin in the treatment of experimental P. aeruginosa pneumonia enhanced eradication of P. aeruginosa and mitigated pulmonary inflammatory changes.

Aerosols↗
PubMed1993

Effects of hypothyroidism on jejunal mucosal function: study by in situ luminal perfusion in rats.

To assess the effects of hypothyroidism (HT) on small-intestinal function, HT was induced in rats (120-150 g) by methimazole in drinking water. After 6 wk of methimazole, intestinal absorption studies were performed in HT and in control (C) rats by in situ luminal perfusion of a 20-cm proximal jejunal loop with a bicarbonate buffer containing sodium, glucose or fructose, glycine or lysine, and phenol red as a nonabsorbable marker for determination of water fluxes. Mucosa from the perfused segment was taken for assay of disaccharidases and ATPases and for light and electron microscopy. Compared with C rats, HT rats had significantly lower jejunal transport rates of water (2.54 +/- 0.36 versus 5.02 +/- 0.7 microL/min/microgram mucosal protein, p < 0.03), sodium (37.1 +/- 10.3 versus 102.7 +/- 18.6 mumol/min/microgram protein, p < 0.05), and glucose (1.49 +/- 0.28 versus 5.17 +/- 0.82 mumol/min/microgram protein, p < 0.02). A reduction in glycine transport was also observed but did not attain statistical significance (p = 0.058). Fructose and lysine transport was unchanged. Mucosal sucrase and lactase activities were similar in both groups, but Na,K-ATPase was significantly lower in HT rats (1.17 +/- 0.3 versus 4.03 +/- 1.5 mumol inorganic phosphate/h/mg protein; p < 0.05), with a diminution of ouabain binding sites by 41.5%. Light microscopy of jejunal mucosa from HT rats did not differ from that from C rats; electron microscopy showed mild mitochondrial swelling in HT enterocytes. A group of HT rats were treated with L-thyroxine during 4 wk; these rats had absorption rates, mucosal enzyme activities, ouabain binding, and mucosal morphology not different from C rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Mucolipidosis III presenting as a rheumatological disorder.

Genetic disorders of the osseous skeleton constitute a challenging area of differential diagnosis. Three patients, 2 girls and 1 boy, were referred to our pediatric rheumatology clinic because of progressive stiffness of their hands and flexion contractures of fingers, accompanied by additional musculoskeletal changes. One of the girls had been diagnosed in early childhood as having juvenile rheumatoid arthritis, the other was suspected to have scleroderma, and the boy had been labelled with "Hurler's syndrome." On evaluation, all 3 patients had the clinical and roentgenographic features of mucolipidosis III; the diagnosis of mucolipidosis III was confirmed by enzymatic assays. We call for an awareness of pediatricians, rheumatologists and orthopedic surgeons to the "rheumatological" presentation of mucolipidosis III. The establishment of a precise diagnosis will lead to adequate management and will allow appropriate genetic counseling.

Arthrography↗
PubMed1992

[Masturbation in infancy simulating convulsive disorder].

We describe a 7-month-old girl referred for evaluation of a convulsive disorder. The tentative diagnosis of epilepsy was based on what were apparently paroxysmal events which occurred many times during a day. A cousin had suffered from infantile spasms and is mentally retarded. The episodic "attacks" in our patient consisted of sudden rhythmic body movements, crossing of thighs, altered awareness, glassy stare and profuse sweating. While the attacks subsided spontaneously, they could easily be aborted by changing the infant to a sitting position or by picking it up and holding it, when it would revert to completely normal behavior. A detailed history and personal observation of the "attacks" made it clear that they were really physical manifestations of masturbation. The diagnosis of epilepsy was therefore discarded. Awareness of masturbation in infants is essential for establishing the correct diagnosis, and spares infants and families many superfluous investigations and the anxiety associated with a diagnosis of convulsive disorder in children.

Diagnosis, Differential↗