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R Bass

Publications and source records attributed to R Bass.

At least 19 recordsLinked to original sources
PubMed1992

The uninsured and the debate over the repeal of the Massachusetts universal health care law.

OBJECTIVES: The debate in Massachusetts over the repeal of the first state-based "pay or play" universal health plan is discussed using data from a survey of 1066 Massachusetts households. The survey attempted to measure the problems of the uninsured, to estimate the likelihood that they would buy insurance if offered, and to calculate the proportion of the uninsured who would be covered under an employer mandate. DESIGN: A survey conducted in person and by telephone in 1066 households, with an oversample of uninsured households, using stratification, clustering, disproportionate sampling, and poststatistical weighting. PARTICIPANTS: Adults aged 18 years and older who were knowledgeable about the insurance status of persons in their household. MAIN OUTCOME MEASURES: Insurance status, employment status, access to and use of health services, and willingness to purchase health insurance. RESULTS: First, the present system of hospital-based uncompensated care in Massachusetts is inadequate by itself to meet the needs of uninsured residents. Uninsured persons are less likely than insured ones to seek medical care for chronic health problems and serious symptoms requiring evaluation. Second, 83% of uninsured families and 24% of uninsured individual respondents would purchase one of several insurance options with 30% of the cost subsidized. Last, the employer mandate provisions of the legislation would cover 43% of the uninsured in Massachusetts. CONCLUSION: In the current economic climate, the political viability of the universal health care plan and similar national initiatives is uncertain given the intractable conflict between perceptions of the financial stability of small businesses that do not offer insurance and the health care needs of uninsured individuals.

Cluster Analysis↗
PubMed1992

A proposed approach to regulating contaminated soil: identify safe concentrations for seven of the most frequently encountered exposure scenarios.

Since 1980, more than 10,000 sites in the United States have been shown to contain soil which has elevated concentrations of various xenobiotics. Since that time, guidelines for deciding whether the level of contamination is worthy of concern have been proposed or promulgated by dozens of local, state, and federal regulatory agencies. Unfortunately, there has been little consistency in the guidelines suggested for each soil contaminant. For example, (a) the basis or rationale for some of the cleanup levels is unclear, (b) approaches to setting cleanup levels vary between states and agencies, (c) cleanup objectives often vary among agencies within the same state, and (d) the cleanup levels are usually set in a scientifically haphazard manner. This paper proposes that the most cost-effective and efficient way to quickly regulate contaminated soil is to establish "safe" concentrations for each chemical for the seven most common exposure scenarios. These exposure scenarios include (1) residential, (2) industrial, (3) agricultural, (4) recreational, (5) groundwater, (6) wildlife and aquatic species, and (7) runoff/erosion of particulates to waterways. The scientific approach and rationale for calculating the cleanup criteria are illustrated by evaluating dioxin and benzene, toluene, and xylene (BTX). The methods suggested here indicate that levels of dioxin of 25 and 50 ppb in residential and industrial soils, respectively, should be acceptable. The predominant concern for the agricultural and recreational scenarios is the runoff of particulates to waterways. For BTX, benzene will dictate the degree of cleanup and the primary hazard at most residential sites will be the inhalation of vapors. Benzene concentrations of 2.5, 14, and 250 ppm should be acceptable for residential, industrial, and recreational soils, respectively. Depending on the depth to groundwater and aquifer use, protection of groundwater may be the driving concern for establishing BTX cleanup levels and must be determined using site-specific factors.

Adult↗
PubMed1992

Are newer scientific concepts in regulatory toxicology used timely and appropriately?

Laws regulating toxicology (e.g. toxic thresholds allowed, poison classes or definition of necessary preclinical testing) might improve health and save lives. Scientific facts will always serve as a mandatory base for political decision-making, but there will also be additional influences (perception and acceptance of risks, possible benefits, economic considerations etc.). These latter factors may vary considerably from one society to another. The Delaney clause prohibited the marketing of any product which was found to be carcinogenic in animals. Due to their benefits, exceptions were made for drugs. In other countries, too, other chemicals could be an exception due to a different perception of the risk or different scientific evaluation. Clear cases of major events always trigger changes in legislation. When in 1937 a newly-marketed sulfanilamide elixir led to severe kidney damage and 70 deaths, the FDA quickly endorsed the propositions of the investigation team set up by the American Medical Association: animal testing in two species with histopathologic examination before a marketing authorization could be granted became mandatory. A similarly rapid reaction followed in Europe when it was detected that Thalidomide was responsible for malformations in the offspring of mothers who had taken the drug in early pregnancy. When the effects are more difficult to link to a chemical, there may be time delays in regulatory actions. However, a sophisticated evaluation system was introduced for better monitoring of drug and chemical hazards. Some examples will be given in order to discuss the difficulties of timely and appropriate use of scientific findings.

Animals↗
PubMed1992

Current guidelines for the preclinical safety assessment of therapeutic proteins.

Guidelines concerning the preclinical safety assessment of therapeutic proteins are available, e.g. in the European Community (EC Notes for Guidance). Unlike rather rigidly prescribing test systems such as those known for chemical substances, it is agreed that for biotechnologically-produced products, testing may be quite different. Those guidelines which allow for a true case-by-case development have been considered the best; however, regulatory authorities are expected to disagree ex post with the approach chosen earlier. To allow for a scientific rationale, which includes the freedom to deviate from the expected norm, guidance must include an offer for discussion of requirements. This combination of recommendations (not requirements) with optional discussions has been the European approach. Although the American approach is known to be somewhat more case-by-case oriented, and the Japanese approach is known to be somewhat more strict, the outcome of drug development, i.e. the application of guidance, in the three regions has been strikingly similar. This underlines the importance of a pharmaceutical manufacturer and his ability to interpret the rules in the light of the product to be developed.

Animals↗
PubMed1991

Considerations regarding the development of individual nonclinical test strategies in the European Community.

The wish of pharmaceutical companies to be given the most binding possible preclinical test programmes for a new product, and the tendency of authorities to regulate to a great extent the preclinical testing of new drugs (especially at a multinational level), has led to differing requirements and practices in preclinical testing in different areas of the world. These differing requirements and practices have of necessity brought in their wake varying scientific criteria, with particular regard to animal protection, ethical standards, as well as imposing apparently unjustified extra financial costs. In order to improve this situation, the development of drug-specific preclinical test strategies is proposed in a drafted E. C. Note for Guidance, which incorporates already existing drug-testing guidelines and method recommendations. This draft Note for Guidance points to general methods of analysing problems and reaching decisions and thus appears to be worthy of recommendation as practical and desirable. It requires the co-operation of drug producers and supervisory authorities at a high scientific and ethical level. With regard to the state-of-the art and the socio-political background, the fulfillment of these requirements would appear not only to be appropriate but also imperative. To put them into practice would contribute enormously to the improvement of drug development and to de-emotionalization of the public debate. Therefore, comments on these draft guidelines from societies and associations are urgently sought and awaited with keen interest.

Animals↗
PubMed1990

Basic requirements for the toxicity testing of antimicrobial agents.

The regulations in different countries on the toxicological testing of antimicrobial agents are similar and harmonized on an international basis. Existing requirements cover both the standard investigations performed with any other new class of therapeutic drug and investigations necessary due to the specific features of anti-infective agents. Such features are the therapeutic target (the microorganisms), the need to provide adequate treatment of patients even during clinical trials, and the potential of the drug to induce certain adverse reactions. The combination of toxicity tests used will be determined by the drug, its class and current knowledge.

Animals↗
PubMed1989

Stereological study of the developing distal femoral growth plate.

The distal femoral growth plate has a uniquely convoluted structure comprised of four mammillate processes. Factors contributing to the development of these processes and overall plate geometry were explored using three-dimensional image analysis of the canine distal femoral epiphysis. The growth plate at birth remains relatively flat until ossification of the epiphysis begins at 1 week of age. Epiphyseal ossification proceeds eccentrically, projecting in the medial-lateral and anterior-posterior directions. Growth plate activity indexed by [3H]thymidine labeling and plate thickness revealed regional differences in cell proliferation. This was measured as a decreased labeling index and thinning of the growth plate in areas capped by the ossifying epiphysis. The eccentric ossification pattern and associated variations in growth plate activity result in definition of an "intraphyseal" groove and medial-lateral oriented sulcus. The groove and sulcus bisect the plate into four quadrants, giving rise to a convoluted structure composed of four areas of plate elevations termed mammillary processes (MP). By 5 weeks, the pattern of ossification results in greater development of the MP in the anterior-medial quadrant and in decreasing order, in the posterior-medial, anterior, and posterior-lateral quadrants. By 10 weeks, a uniform rate of cell proliferation was observed coincident with completion of ossification of the epiphysis. The data suggest that localized variations in growth plate proliferation are associated with ossification of the epiphysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1987

Experience with mutagenicity testing of new drugs: viewpoint of a regulatory agency.

Quality and quantity of mutagenicity testing were analyzed for drugs with new active compounds which were submitted for registration in the Federal Republic of Germany from mid 1982 to mid 1986. A large variety of deficiencies was found, applying to selection and number of mutagenicity tests as well as to test performances. Only 65 out of the 144 drugs submitted for registration were tested sufficiently in the initial phase of registration. From 1982 to 1986 this situation has not been changed markedly. Inadequate test performance still remains the main reason for insufficient testing, leading in some cases to artificially positive results. For in vivo tests the selection of test species was mainly motivated by technical reasons and not by characteristics of the test compound. Most of the insufficiencies were eliminated during the second phase of registration. In some cases insufficient mutagenicity testing led to consequences concerning risk-benefit assessment of the drug and its regulation.

Animals↗
PubMed1986

Transfer of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) via placenta and milk, and postnatal toxicity in the mouse.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) was found to be efficiently transferred to mouse neonates and offspring by lactating mothers. During the first 2 postnatal weeks the pups received doses of TCDD via the milk which were, on a body weight basis, similar to those which had been administered prenatally to their mothers. The distribution of TCDD in the offspring (high in liver, low in other tissues) was similar to that found in the maternal organism. Maternal TCDD levels rapidly decreased during the lactation period while tissue levels in the nursing pups increased, resulting in offspring tissue levels which greatly exceeded those of their mothers at the respective 3-week periods after birth. The postnatal development of pups from mothers treated on days 14-17 of gestation and nursed by untreated foster mothers was studied. Postnatal mortality was increased. Surviving animals did not exhibit visible signs of abnormal development, although the reduced number of pups per litter may have contributed to this apparently normal development. In small rodents excretion into milk constituted a major pathway for the elimination of maternal TCDD. Whether the same holds true for man is still unknown, but the measurement of TCDD levels in breast milk may be an appropriate and practical method for the assessment of human exposure to this substance.

Aging↗
PubMed1986

Responses of male and female physicians to medical complaints in male and female patients.

Workups by male and female physicians in response to five common complaints in a sample of 200 men and women-100 married couples-revealed no significant differences in the extent and content. This study contrasts with observations made in a previous study of male physicians who were found to perform more extensive workups for men than for women. The present study differs from the previous one in several respects, however: (1) the physicians are significantly younger, (2) the patients are significantly older, (3) the physicians practice in a prepaid health maintenance organization as opposed to a fee-for-service group, and (4) the practice consists of men and women partners. If the first and last factors are the most important in accounting for the present observations, it is possible that whatever sexist behavior exists will decline with the infusion of young physicians-both men and women-into the evolving medical practice setting.

Adult↗
PubMed1979

Elucidation of an A and L system for amino acid transport in the human lymphoblast using a membrane filtration technique.

Optimum conditions have been established for the measurement of amino acid transport by human lymphoblastoid cell lines using a membrane-filtration technique. The parameters we found to be important for the reproducibility of the method are: the types and combination of filters, the strength of the vacuum applied to the filters and the density of the cultures at the time of harvesting and during uptake and filtration. We found that bovine serum albumin added to phosphate buffered saline (PBS) glucose in which the cells are washed, resuspended and assayed is essential for the maintenance of viability, the prevention of clumping and the retention of the accumulated amino acid. Using this procedure we have characterized two transport systems for the neutral amino acids; an A and an L system, which are similar but not identical to the A and L systems characterized in rodent cell lines. These A and L systems have characteristically lower Km's and Vm's for alanine and phenylalanine, when compared to rodent cell lines. In addition, we find alpha-AIB to be a poor competitor of alanine and phenylalanine uptake.

Alanine↗
PubMed1979

Effect of intact parathyroid hormone on hepatic glucose release in the dog.

The liver has been shown to remove parathyroid hormone (PTH) from its arterial circulation by a mechanism that is selective for the intact form of the peptide (PTH 1-84). The present studies demonstrate that PTH has biologic effects on the liver in vivo. Bovine PTH 1-84 stimulated hepatic glucose release in dogs with indwelling hepatic vein catheters from basal values of 31+/-8 to 68+/-9 mg/min per kg after bolus injections of PTH. The effect on hepatic glucose release was apparent by 5 min and persisted for the 80 min of observation. The NH(2)-terminal PTH fragment (syn b-PTH 1-34) had no effect. Bovine PTH 1-84 administered in doses designed to produce circulating levels of immunoreactive PTH similar to the endogenous levels observed in uremic dogs also increased the incorporation of (14)C from infused [(14)C]alanine into glucose, and increased estimated hepatic uptake of both chemical and [(14)C]alanine, while increasing hepatic glucose release. Thus, administration of "physiologic levels" of b-PTH 1-84 stimulated hepatic glucose release in part through increased gluconeogenesis in vivo, whereas syn b-PTH 1-34 had no demonstrable effect. Circulating levels of insulin rose after PTH administration, an increase which presumably represents a secondary response to the rise in glucose release. These results suggest that the liver is a target organ of PTH, and that PTH might potentially alter carbohydrate metabolism during hypersecretion. They also suggest that hepatic uptake of PTH may be related in part to production of a specific biologic effect rather than just simple peptide degradation.

Animals↗