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H T Blumenthal

Publications and source records attributed to H T Blumenthal.

11 recordsLinked to original sources
PubMed1992

Studies on lead exposure in patients of a neighborhood health center: Part II. A comparison of women of childbearing age and children.

The second part of this study deals with blood lead (PbB) levels in 541 pregnant women and 351 nonpregnant women of childbearing age residing in the health center's catchment area. Each blood sample was analyzed for erythroprotoporphyrin (EP) and PbB. Comparisons of these data were made with national data on women of childbearing age and with children in our catchment area, as well as with children nationally. Mean PbB and prevalence rates at greater than or equal to 10 and greater than or equal to 15 micrograms/dL were higher in the nonpregnant women of the catchment area than in the pregnant women. For comparison with women nationally, the data on these two groups were combined because national data did not clearly distinguish between pregnant and nonpregnant women. The women in the catchment area showed mean PbB and prevalence rates at the two ranges noted above that were not only higher than in white women but also generally higher than in black women nationally. Thus, this rank order was similar to that reported earlier for children. The comparisons between women and children living in the same environment showed that the children have significantly higher mean PbBs and prevalence rates at the two ranges than the women. The physiological and environmental bases for these differences are discussed. As in the study on children, the EP is also not adequate as a screening procedure for identifying women with PbB levels greater than or equal to 25 and greater than or equal to 15 micrograms/dL.

Adolescent↗
PubMed1991

Studies on lead exposure in patients of a neighborhood health center: Part I. Pediatric patients.

A sharply focused study is presented defining the demographic characteristics of the catchment area of a St Louis health center and determining the blood lead (PbB) levels in children from 1977 to 1989. The sources of lead exposure are examined, and the adequacy of erythroprotoporphyrin (EP) determinations are evaluated to identify children with toxic levels. Mean PbB levels and prevalence rates at higher ranges were not only substantially higher in the catchment area population than in white children, but also significantly higher than in black children nationally. Since 1980, mean PbB declined progressively in the catchment area children, but it was not until 1989 that the mean PbB had declined to the 1980 level in white children nationally. PbB parameters in the catchment area children were not only higher than in children in other St Louis neighborhoods, but also higher than in children living in towns adjacent to a lead smelting operation. The environmental sources of lead considered here do not appear to fully account for the higher PbB levels in the children in the catchment area. Nutritional factors also need to be considered. Furthermore, the EP lacks both sensitivity and specificity for identifying children with PbB levels greater than or equal to 25 micrograms/dL and greater than or equal to 15 micrograms/dL. While this study identifies a community that has experiences a high prevalence of lead toxicity in its children, it also suggests that nationwide and even citywide estimates of the prevalence of lead toxicity based on EP screening may be significantly lower than actual prevalences.

Child, Preschool↗
PubMed1987

Immunopathological studies on thyroid immunity. IX. Thyroid and renal amyloidosis in thyroglobulin immunized rabbits.

In serial studies of immunopathologic changes in an animal model of thyroiditis 52 rabbits were immunized with either bovine, porcine or human thyroglobulin (Tg) in Freund's complete adjuvant, while another 47 animals served as noninjected or adjuvant injected controls. The immunized animals were divided into two groups, one receiving an initial series of only three Tg injections while the other received, in addition, challenging injections over an 8-week period. The immunized animals were killed over a period of 6-34 months after the last Tg injection, and untreated controls were killed at comparable ages. In Tg immunized animals, lymphocytic thyroiditis was encountered in 25 per cent and thyroid amyloid in 17 per cent; glomerular amyloid was encountered in 44 per cent with diffuse lesions in 8 per cent, nodular lesions in 17 per cent and a mixture of the two in 19 per cent. That the thyroid and glomerular hyaline deposits contained amyloid was shown by various histochemical criteria, as well as by the presence of typical fibrils on electron microscopy. Immunohistochemical studies indicated that the amyloid was predominantly of the AA type. Rabbits receiving challenging Tg injections, in addition to the initial series, showed only thyroiditis and nodular glomerular lesions most of which were amyloid. Whilst the vast majority of rabbits with lymphocytic or amyloidotic responses showed both thyroid and renal lesions, a small percentage of animals showed only a lesion of one or the other of these two organs. It is of interest that the thyroid and renal amyloid lesions, described for the first time with induced thyroglobulin immunity, were not detected in other earlier short term investigations.

Amyloidosis↗
PubMed1979

An in vivo and in vitro study of an aging-related neuron cytoplasmic-binding antibody in male Fischer rats.

Fischer 344 male rats showed a low average level (less than ++) of in vivo as well as in vitro neuron binding antibody at 3, 15, and 26 months. However, a significant increase with age in average intensity of binding was observed with both the in vivo and the in vitro conditions. If a criterion of ++ is used as an antibody binding level likely to have biological consequences, the percent of in vivo cases showing foci of ++ or greater intensity also rises with age from 20 to 80%; a criterion of +++ gives an in vivo rise with age of only from 10 to 20%. The in vitro incidence with the ++ criterion is already 80% at three months and rises to 90%; with the +++ criterion the incidence with age rises from 20 to 80%. No evidence was obtained to support the concept that there is a weakening of the blood-brain-barrier in 26 month rats either by the systemic injection of trypan blue or by a comparison of intensity of antibody binding between extra- and intra-barrier neurones.

Aging↗
PubMed1978

Aging: biologic or pathologic?

If disease is only case casually related to aging, the prevailing strategy of dealing with each disease category is appropriate; if they are linked causally, the current strategy may not only be inappropriate but prove futile. The extent to which optimal gerontologic care can delay the onset of biologic deterioration, together with the use of short-lived animal models for research, may eventually resolve this issue.

Aged↗
PubMed1978

Neuron-thymic lymphocyte binding by serum IgG of 90- and 500-day-old female Wistar albino rats.

In vivo and in vitro IgG binding to neurons was determined by the direct and indirect immunofluorescence and immunoperoxidase techniques in 90- and 500-day-old female Wistar rats. The sera were also tested against other organs of 90- and 300-day-old rats, and an absorption technique was carried out with minced thymus. Only 1 90-day-old rat showed positive in vivo neuron binding. One serum of a young (6.7%) and 17 sera of old (42.5%) rats were positive by the in vitro procedures. The 1 young and 4 of the old positive sera cross-reacted with thymocytes, and when 3 of these were subjected to absorption, neuron igG binding capacity was removed. Significant cross-reactivity with other organs could not be demonstrated. These observations indicate that in these rats there are at least two kinds of serum neuron binding IgG which significantly increase with age; one of these cross-reacts with thymus and the other does not.

Age Factors↗