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Biomedical subjects

M A Hall

Publications and source records attributed to M A Hall.

At least 163 records · Page 9Linked to original sources
PubMed1967

Studies on Cellulose Synthesis by a Cell-free Oat Coleoptile Enzyme System: Inactivation by Airborne Oxidants.

Particulate cell wall polysaccharide synthetase from oat coleoptiles could use either guanosine diphosphate glucose or uridine diphosphate glucose; the latter was a much more effective glucose donor. The neutral polymer derived from uridine diphosphate glucose utilization yielded, after cellulase digestion, mostly cellobiose and to a lesser extent a substance tentatively identified as a mixed-linkage beta1,4 = beta1,3-trisaccharide; only cellobiose was found after guanosine diphosphate glucose utilization. The uridine diphosphate glucose utilizing system was inactivated by peroxyacetyl nitrate treatment of intact tissue and to a lesser extent by ozone treatment suggesting that this system is a possible site of interference with cellulose and non-cellulosic glucan biosynthesis in vivo. Direct treatment of the enzyme in vitro by peroxyacetyl nitrate, iodoacetamide or p-chloromercuribenzoate also inactivated the enzyme, indicating that the mechanism of inactivation possibly involves reaction with sulfhydryl groups.

Journal Article↗
PubMedDate not supplied

Patients' fear of genetic discrimination by health insurers: the impact of legal protections.

PURPOSE: The impact of laws restricting health insurers' use of genetic information has been assessed from two main vantage points: (1) whether they reduce the extent of genetic discrimination and (2) whether they reduce the fear of discrimination and the resulting deterrence to undergo genetic testing. A previous report from this study concluded that there are almost no well-documented cases of health insurers either asking for or using presymptomatic genetic test results in their underwriting decisions, either before or after these laws, or in states with or without these laws. This report evaluates the perceptions and the resulting behavior by patients and clinicians. METHODS: A comparative case study analysis was performed in seven states with different laws respecting health insurers' use of genetic information (no law, new prohibition, mature prohibition). Semistructured interviews were conducted in person with five patient advocates and with 30 experienced genetic counselors or medical geneticists, most of whom deal with adult-onset disorders. Also, multiple informed consent forms and patient information brochures were collected and analyzed using qualitative methods. RESULTS: Patients' and clinicians' fear of genetic discrimination greatly exceeds reality, at least for health insurance. It is uncertain how much this fear actually deters genetic testing. The greatest deterrence is to those who do not want to submit the costs of testing for reimbursement and who cannot afford to pay for testing. There appears to be little deterrence for tests that are more easily affordable or when the need for the information is much greater. Fear of discrimination plays virtually no role in testing decisions in pediatric or prenatal situations, but is significant for adult-onset genetic conditions. CONCLUSION: Existing laws have not greatly reduced the fear of discrimination. This may be due, in part, to clinicians' lack of confidence that these laws can prevent discrimination until there are test cases of actual enforcement. Ironically, there may be so little actual discrimination that it may not be possible to initiate good test cases.

Ethics, Medical↗
PubMedDate not supplied

The geography of health insurance regulation.

The health insurance market consists of three distinct segments--individual, small group, and large group--each governed by different economic and regulatory structures. A number of border-crossing techniques have arisen for avoiding the burdens of one segment and capitalizing on the benefits of others. Drawing from extensive qualitative research into the functioning of existing market structures, this paper describes these techniques and their purposes and effects. This road map helps to identify which reform proposals seek to produce true economic efficiencies and which have the potential to undermine previous reform objectives.

Colorado↗
PubMedDate not supplied

Disclosure of physician incentives: do practices satisfy purposes?

Under legal pressure, discussion has quickly shifted from whether health plans should disclose how they pay their physicians to how, when, and what should be disclosed and by whom. This paper describes health plans' disclosure practices and evaluates their adequacy and likely impact. It begins by explaining how different reasons for disclosure alter the form and content of disclosure, illustrating these approaches with actual examples. The paper concludes with a recommended approach that attempts to layer and stage disclosures so that people have as much information as they want, when they need it.

Attitude to Health↗
PubMedDate not supplied

HealthMarts, HIPCs (health insurance purchasing cooperatives), MEWAs (multiple employee welfare arrangements), and AHPs (association health plans): a guide for the perplexed.

This paper considers how pending proposals to authorize new forms of group purchasing arrangements for health insurance would fit and function within the existing, highly complex market and regulatory landscape and whether these proposals are likely to meet their stated objectives and avoid unintended consequences. Cost savings are more likely to result from increased risk segmentation than through true market efficiencies. Thus, these proposals could erode previous market reforms whose goal is increased risk pooling. On the other hand, these proposals contain important enhancements, clarifications, and simplification of state and federal regulatory oversight of group purchasing vehicles. Also, they address some of the problems that have hampered the performance of purchasing cooperatives. On balance, although these proposals should receive cautious and careful consideration, they are not likely to produce a significant overall reduction in premiums or increase in coverage.

Cost Savings↗
PubMedDate not supplied

The structure and enforcement of health insurance rating reforms.

Requiring health insurers to cover everyone who applies regardless of health status--an approach called "guaranteed issue"--is severely hampered without accompanying rating restrictions that keep insurance affordable for higher-risk people. The degree of rating flexibility also determines how much insurers can continue to compete based on their skills at risk selection, and how well they can counter adverse selection. Therefore, the structure and enforcement of rating reforms are essential to how insurance market reforms function. Based on an in-depth qualitative study in seven states with insurers, agents, and regulators, this article explains the factors that determine the stringency of rating reforms, and details how various aspects of rating restrictions can be used strategically to engage in greater risk segmentation than first appears possible. The article concludes by reflecting on the appropriate degree of complexity in rating rules, and it offers recommendations for crafting rating reforms that avoid unintended consequences.

Actuarial Analysis↗
PubMedDate not supplied

Premature ovarian failure in women with juvenile idiopathic arthritis (JIA).

OBJECTIVE: To examine the effect of longstanding juvenile idiopathic arthritis (JIA) on menstrual irregularity and the incidence of premature ovarian failure in women. METHODS: Women with longstanding JIA who had abnormal or absent menstrual cycles had their circulating levels of gonadotrophins measured to check for the presence of ovarian failure. Disease demographics and subsets, function, age at onset of menstrual irregularity, previous medical intervention, concurrent diseases and history of pregnancy/delivery were documented. RESULTS: 177/187 (95%) of female adults with JIA who were identified and contacted, participated in the study. The average age at review was 35.4 years (19-78) with average disease duration of 28.7 years. 47.4% of all patients had clinically active arthritis. 44.6% of all patients had severe disability (HAQ score > 1.5). Six patients had premature ovarian failure unrelated to medication use, comprising 3.4% of the females in the study, compared to an expected incidence of 1% in the general population (p < 0.01). In addition, three (1.7%) of these had onset of symptoms before age 30, compared to an expected incidence of 0.1% in the general population (p < 0.01). The average maternal age at first delivery in women with JIA (27.2 years) was higher than the general population (23.5 years). CONCLUSION: Idiopathic premature ovarian failure was more commonly found in individuals with juvenile idiopathic arthritis. In addition a small number of patients had iatrogenic premature ovarian failure related to chlorambucil use.

Adult↗
PubMedDate not supplied

The ethics of managed care: a dose of realism.

This article examines the ethics of medical practice under managed care from a pragmatic perspective that gives physicians more useful guidance than existing ethical statements. The article begins by stating the authors' starting premises and framework for constructing a realistic set of ethical principles: namely, that bedside rationing in some form is permissible; that medical ethics derive from physicians' role as healers; that actual agreements usually trump hypothetical ones; that ethical statements are primarily aspirational, not regulatory; and that preserving patient trust is the primary objective. The authors then articulate the following concrete ethical guides: financial incentives should influence physicians to maximize the health of the group of patients under their care; physicians should not enter into incentive arrangements that they would be embarrassed to describe accurately to their patients or that are not in common use in the market; physicians should treat each patient impartially, without regard to source of payment, and in a manner consistent with the physician's own treatment style; if physicians depart from this ideal, they must tell their patients honestly; and it is desirable, although not mandatory, to differentiate medical treatment recommendations from insurance coverage decisions by clearly assigning authority over these different roles and by having physicians to advocate for recommended treatment that is not covered.

Conflict of Interest↗
PubMedDate not supplied

A multicentre pilot study of sulphasalazine in juvenile chronic arthritis.

In this multicentre pilot study of sulphasalazine in juvenile chronic arthritis, the mode of onset and course of the disease, and when available, the HLA status, was recorded on the entry form. After appropriate clinical and laboratory appraisal, sulphasalazine up to 40 mg/kg/day was given for one year with assessments at 0, 1, 3, 6, 9 and 12 months. Fifty-one patients enrolled, 8 of whom were withdrawn because of side effects. In the remainder by 12 months a good effect was noted in 12, 8 having pauci-articular onset disease commencing after the age of 9 years, of whom 6 carried HLA B27. It was relatively ineffective in the other subgroups. The frequency and severity of side effects was similar to that seen in adults. Further evaluation in controlled trials is required in older onset pauci-articular arthritis, taking due note of the patient's HLA status, and also in juvenile psoriatic arthritis and seropositive juvenile rheumatoid arthritis.

Adolescent↗