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R Hirsch

Publications and source records attributed to R Hirsch.

158 records · Page 9Linked to original sources
PubMedDate not supplied

Antibody-mediated endocytosis of G250 tumor-associated antigen allows targeted gene transfer to human renal cell carcinoma in vitro.

Specific gene transfer into targeted tumor cells remains a critical issue for the development of systemic gene therapy protocols. With this end in view, we have tested the possibility of selectively directing genes to tumor cells through the recognition of tumor-associated antigens (TAA). This was approached in vitro on four human renal cell carcinoma (RCC) lines by means of the highly specific mouse G250 monoclonal antibody (mAb) chemically conjugated to a plasmid DNA conveying a reporter activity. This mAb directed to a TAA that is present on 95% of primary RCCs and on 60% of metastatic human RCCs was extensively characterized, including during clinical trials. Epifluorescence microscopy analysis indicated that upon specific binding to G250 TAA, G250 mAb alone or conjugated to plasmid DNA was internalized by an active endocytic process and colocalized with the transferrin concentrated in the late recycling perinuclear compartment. We also observed that both unconjugated G250 mAb or G250 mAb conjugated to plasmid DNA remained in the perinuclear region of the cells for > or = 20 hours and were not rapidly translocated to lysosomes or recycled to the plasma membrane. In contrast, unconjugated plasmid DNA was not internalized. After transfection of G250 TAA-positive RCC lines with G250 mAb conjugated to a plasmid cDNA encoding mouse interleukin-2, a significant and sustained production of mouse interleukin-2 protein was detected from days 5-15 and was abrogated by inhibiting the internalization process. Altogether, our data showed that endocytosis of G250 TAA should be the basis of gene transfer to RCC, suggesting that targeting of TAA capable of internalization may be the basis of new approaches for designing alternative cancer gene therapy procedures.

Animals↗
PubMedDate not supplied

Setting inventory levels for hospital blood banks.

A method is devised to predict the hospital blood bank inventory of each of the eight blood types that will be adequate on all but a given fraction of days (shortage rate). Analysis of the model confirms and extends prior statistical models and provides a rationale for a number of observations made on some common blood inventory practices. Comparison of the relationship between inventory levels and shortage rates predicted by the model and that calculated from data from 21 hospital blood banks of varying sizes, located in four separate parts of the country, reveals agreement within approximately 10 per cent. A procedure is presented and allows blood banks to select inventory levels and shortage rates based on their mean demand for blood.

Blood Banks↗
PubMedDate not supplied

Genealogy construction in a historically isolated population: application to genetic studies of rheumatoid arthritis in the Pima Indian.

PURPOSE: Due to the characteristics of complex traits, many traits may not be amenable to traditional epidemiologic methods. We illustrate an approach that defines an isolated population as the "unit" for carrying out studies of complex disease. We provide an example using the Pima Indians, a relatively isolated population, in which the incidence and prevalence of Type 2 diabetes, gallbladder disease, and rheumatoid arthritis (RA) are significantly increased compared with the general U.S. population. A previous study of RA in the Pima utilizing traditional methods failed to detect a genetic effect on the occurrence of the disease. METHODS: Our approach involved constructing a genealogy for this population and using a genealogic index to investigate familial aggregation. We developed an algorithm to identify biological relationships among 88 RA cases versus 4,000 subsamples of age-matched individuals from the same population. Kinship coefficients were calculated for all possible pairs of RA cases, and similarly for the subsamples. RESULTS: The sum of the kinship coefficient among all combination of RA pairs, 5.92, was significantly higher than the average of the 4,000 subsamples, 1.99 (p < 0.001), and was elevated over that of the subsamples to the level of second cousin, supporting a genetic effect in the familial aggregation. The mean inbreeding coefficient for the Pima was 0.00009, similar to that reported for other populations; none of the RA cases were inbred. CONCLUSIONS: The Pima genealogy can be anticipated to provide valuable information for the genetic study of diseases other than RA. Defining an isolated population as the "unit" in which to assess familial aggregation may be advantageous, especially if there are a limited number of cases in the study population.

Arizona↗
PubMedDate not supplied

[Psychic changes in systemic lupus erythematosus: a multidisciplinary prospective study].

Despite the high prevalence of psychic symptoms in lupus patients, there are few systematic studies in this area. Through a multidisciplinary approach, the authors developed a prospective study to characterize and correlate psychopathological aspects with clinical and laboratory data concerning neural manifestations of the disease. Out of 23 patients studied, 12 showed psychic alterations, which were interpreted as primary manifestations of the disease. All of them presented organic mental syndromes (DSM-III-R) in which cognitive symptoms were the most prominent, followed by affective, catatonic and hallucinatory features. The neurologic findings (seizure, migraine and muscular atrophy), as well as the ophthalmologic alterations (hemorrhage and soft exudates) were frequent and concomitant with the psychic features. The laboratory findings were: LE cells 50%; anti-Sm: 16%; anti-U1 RNP: 50%; anti-Ro/SS-A: 50%; anti-nDNA: 58%; decreased CH50 or fractions (C3, C4): 67%; anti-P: 18%; antigangliosides IgG: 67%; antigangliosides IgM: 78%. The cerebrospinal fluid analysis showed: increased cellularity: 18%; elevated protein: 36%; antigangliosides IgG: 67%; antigangliosides IgM: 33%; immunocomplexes: 36%. In spite of the absence of an adequate control group and of the small number of patients, the multidisciplinary approach leads to a better characterization of the nervous system involvement in this disease.

Adolescent↗
PubMedDate not supplied

[Neuropsychiatric disorders in systemic lupus erythematosus: a multidisciplinary review].

Neuropsychiatric alterations appear in 14-75% of lupic patients. Verified in 59% of the patients, psychiatric changes are the most frequent. Psychic symptoms are primarily related to the disease and secondary to uremia, hypertension, infection, and corticosteroids. Manifestations were also seen as a reaction to this chronic disease, which are potentially severe and causing many limitations to the patients. The authors review the literature considering the multidisciplinary aspects of this disease related to its pathogenesis, clinical features, diagnosis, differential diagnosis, and treatment.

Adrenal Cortex Hormones↗