Search PubMed⌕ Search

Biomedical subjects

M Simon

Publications and source records attributed to M Simon.

At least 631 records · Page 35Linked to original sources
PubMed1980

Thromboembolism after insertion of the Mobin-Uddin caval filter.

The occurrence, in one patient, of a life-threatening pulmonary embolus 3 days following insertion of a Mobin-Uddin umbrella filter promoted a review of our experience with this device. Over the past 5 years, 41 patients had umbrella filters inserted at the Beth Israel Hospital. Five patients (12%) had proven or probable pulmonary embolization following filer placement. In four of the seven autopsied patients, thrombus was found on the cardiac side of the umbrella, and in one of these patients a fresh embolus was also found in the pulmonary artery. We conclude that the standard (nonheparin-impregnated) Mobin-Uddin umbrella device offers incomplete protection against pumonary embolization in patients who cannot concurrently receive anticoagulant drugs.

Adult↗
PubMed1980

[Unusual molluscum contagiosum infection in sarcoidosis].

An extremely extension of molluscum contagiosum infection of the skin of a 42 year old man led to detection of pulmonary sarcoidosis. Viral infection can be the result of impaired cellular immunity caused by various diseases or by immunosuppressive therapy. In our case sarcoidosis was the base for an unusual serious course of a molluscum contagiosum infection.

Adult↗
PubMed1980

Hepatic and serum ferritin concentrations in patients with idiopathic hemochromatosis.

Hepatic iron and ferritin concentrations have been measured in needle biopsy specimens from patients with idiopathic hemochromatosis and from patients with other liver diseases. There was an excellent correlation between liver iron and ferritin concentrations in patients with miscellaneous liver diseases, but this was not found for the patients with hemochromatosis either before or after treatment. The proportion of liver iron bound to ferritin was lower in treated and untreated hemochromatosis than in the other patients. This probably reflects the formation of increasing amounts of hemosiderin with increasing iron deposition. Three patients in the early stage of idiopathic hemochromatosis were studied. These patients had high concentrations of hepatic iron and ferritin, but had serum ferritin concentrations within, or just above, the normal stage. These results suggest that, in the early stage of hemochromatosis, there is no failure of ferritin synthesis in the liver and that normal levels of serum ferritin are present either because the total body iron content is within the normal range or because the liver parenchymal cells are not, in the absence of liver damage, an important source of plasma ferritin.

Adult↗
PubMed1980

C-terminal parathyrin (parathyroid hormone) radioimmunoassay in serum with commercially available reagents.

We describe a sequential double-antibody assay for measuring C-terminal parathyrin in serum with commercially available reagents. Intact bovine hormone, used as a working standard, is iodinated by conventional Chloramine T procedures. The antibody affinity is characteristic of high affinity binding (1.4 to 1.6 x 10(10) L/mol of intact parathyrin). The antibody also cross reacts with a C-terminal parathyrin fragment (amino acids 53-84) but not with a synthetic N-terminal parathyrin fragment (amino acids 1-34). The assay thus also measures both a C-terminal fragment of parathyrin and the intact hormone. The detection limit (250 ng/L; 500 int. units/L) is below the reference interval for healthy adults (430-1860 ng/L; 860-3720 int. units/L). Several commonly recognized problems with iodinated parathyrin are eliminated and accuracy and precision of the procedures for standard preparation and calibration are improved. Overall CV (between-run imprecision) is 10-17%. Analytical recovery is 80-90%, and C-terminal parathyrin measured in fresh sera and in sera stored for seven days at 30 degrees C is equivalent.

Adult↗
PubMed1980

Diagnostic utility of C-terminal parathyrin measurement as compared with measurements of N-terminal parathyrin and calcium in serum.

We compared results obtained from two parathyrin (parathyroid hormone) assays with differing specificities, using sera from 172 normal donors and from 98 patients with disorders of calcium regulation. Intact parathyrin was measured in both assays; the C-parathyrin assay also measured the 53-84 amino acid C-terminal hormone fragment; the N-parathyrin assay also measured the 1-34 N-terminal fragment. The reference interval for the C-parathyrin assay (860-3720 int. units/L; 430-1860 ng/L) was markedly higher than for the N-parathyrin assay (460-1260 int. units/L; 230-630 ng/L), a finding consistent with the longer half-life of C-parathyrin fragments in human circulation. Mean C-parathyrin in primary hyperparathyroid sera--5720 (SD 2760) int. units/L or 2860 (SD 1380) ng/L--clearly exceeded the reference interval and values for sera from patients with non-parathyroid malignancy [1740 (SD 760) int. units/L; 870 (SD 380) ng/L]. Secondary hyperparathyroid patients also had supranormal C-parathyrin values: 6100 (SD 2720) int. units/L; 3050 (SD 1360) ng/L. We found no consistent correlation between parathyrin and serum calcium in any clinical group. The two parathyrin assays showed about equal diagnostic power, but their results could not be used interchangeably in sequential monitoring of patients.

Adult↗
PubMed1979

Serum ferritin as a possible marker of the hemochromatosis allele.

To determine whether a correlation exists between the biochemical expression of hemochromatosis and the HLA genotype, we studied 174 family members of 32 persons with the disease. Persons who shared both HLA haplotypes with the proband (and presumably having two hemochromatosis alleles) differed significantly from those who shared only one haplotype (and presumably having one hemochromatosis allele) in terms of serum iron (P less than 0.001 for both sexes), unsaturated iron-binding capacity (P less than 0.01 for female and P less than 0.0001 for male subjects) and serum ferritin (P less than 0.0001 for female and P less than 0.00001 for male subjects). The only significant difference between relatives having one hemochromatosis allele and age and sex-matched controls was related to serum ferritin values in male subjects (P less than 0.05, despite considerable overlap). In our hands, serum ferritin was the best indicator of disordered iron metabolism and was elevated among most homozygous but among few heterozygous family members.

Adolescent↗
PubMed1979

[Biological properties of immunocompetent cells].

Inflammation is characterized by the combined reaction of living tissue of the target organ and various types of white blood cells recruited from the circulation and platelets, which tend to eliminate the injurious agent and to repair the damaged tissue. Much of the current knowledge of the functions and characteristics of human white blood cells has been derived from studies of lymphoid cells from patients with various diseases. The results of recent studies (17, 19, 28) have pointed to the diagnostic importance of the immunocompetent cells. The various characteristics of cells involved in immune mediated reactions of various organs and in circulation in man may lead to a better understanding of immune reactions and finally to effective therapeutic modalities.

Antibody-Producing Cells↗
PubMed1979

[Idiopathic haemochromatosis. Pathogenic and genetic aspects. Detection and prevention (author's transl)].

The basic disorder of iron metabolism in idiopathic haemochromatosis finds expression on at least two levels: the intestinal mucosa (increased iron absorption) and the liver. Its exact nature, however, remains obscure. The role of iron overload in the pathogenesis of the disorder seems clear. Lysosome disruption has recently been proposed as a possible pathogenic factor. Phenotypic family studies have lent considerable weight to the hypothesis of a recessive transmission of idiopathic haemochromatosis. Demonstration of a close link between the disease and the HLA antigen A3 and haplotype A3, B14 has made it possible: to remove all doubt as to the hereditary nature of the disease; identify the underlying gene as located on chromosome 6 near the A locus of the HLA system; demonstrate a recessive mode of transmission; and achieve the early detection of individuals at risk in the family of a patient with the disease. Thanks to this possibility of early detection, the feasability of preventive measures is greatly enhanced.

Alleles↗
PubMed1979

[Idiopathic haemochromatosis. I. Clinical, biological and therapeutic aspects (author's transl)].

Over the last few years the study of idiopathic haemochromatosis has not brought to light any basic change in the overall pattern of organic and metabolic damage produced by the disease and comprising altered skin pigmentation, liver disease, diabete mellitus, heart disease, endocrine dysfunction, bone and joint disease. Nevertheless, certain facets of the clinical picture have been described and progress has been made in understanding the signs of the disease. Although the desferrioxamine test is no without merit, especially if performed after vitamin C administration, for measuring the extent of iron overload, two methods seem better equipped: serum ferritin radioimmunoassay and measurement of iron concentration in a liver biopsy specimen. The HLA antigen A3 and, more especially, haplotype A3, B14, are markers for the genetic basis of the disease. Repeated phlebotomy therapy generally brings about symptomatic improvement and a significant increase in survival.

Bloodletting↗
PubMed1979

[Demonstration by iron overloading study and HLA genotyping of recessive transmission of idiopathic haemochromatosis in two pseudodominant pedigrees (author's transl)].

We studied iron overloading and HLA genotype in two families with overt forms of idiopathic haemochromatosis in two successive generations. In each family the spouse of the patient with overt haemochromatosis in the first generation had clinical and laboratory signs of moderate iron overload and a HLA haplotype A3, B14 and A3, B7 respectively--which is frequently associated with the haemochromatosis gene. This specific HLA haplotype had been transmitted to the second generation patient with overt disease, which thus could be considered as having received a haemochromatosis gene from each parent. Although the finding of cases of overt disease in successive generation firstly suggests a dominant transmission the genetical analysis of these families lead to further strong argument in favour of recessive inheritance of idiopathic haemochromatosis.

Adolescent↗
PubMed1979

Antimicrobial effectiveness in endodontic therapy using formocresol and two new alcoformal agents. Mechanical preparation during the second visit.

Antimicrobial effectiveness of alcoformol two agents (AF 8.85 and AF 3.5) was studied in a clinical trial by means of bacteriologic examination of the root canals. After the initial culture was taken, one of the disinfectants was sealed in the pulp chamber for one week. At the second visit, the root canal was reamed and a second culture was taken. It was found that AF containing 3.5 percent formaldehyde is a satisfactory disinfectant for root canals of vital teeth. A concentration of 8.75 percent was needed for disinfection of teeth with necrotic pulps.

Anti-Infective Agents, Local↗
PubMed1979

Antimicrobial effectiveness in endodontic therapy using formocresol and two new alcoformol agents. Mechanical preparation during the first visit.

Antimicrobial effectiveness of two alcoformol agents (AF 8.75 and AF 3.5) was studied in a clinical trial by means of bacteriologic examination of the root canals. After the initial culture was taken, the root canal was reamed and a second culture was taken. One of the disinfectants was sealed in the pulp chamber for one week. At the second visit, a third culture was taken. No statistically significant differences were found between the effectiveness of the disinfectants; the cumulative effect of mechanical preparation and disinfection was such that initially positive teeth did not differ significantly from initially negative teeth when treated by this procedure.

Anti-Infective Agents, Local↗