The Incidence of Mandated Employer-Provided Insurance: Lessons from Workers' Compensation Insurance

Workers' compensation insurance provides cash payments and medical benefits to workers who incur a work-related injury or illness. Many features of the workers' compensation program parallel features of proposed mandated employer-paid health insurance plans. This paper empirically examines the incidence of the workers' compensation program to infer the likely consequences of mandated health insurance proposals. In certain industries, such as trucking and carpentry, workers' compensation insurance costs are quite large, and vary tremendously within states over time, and across states at a moment in time. This variation is used to identify the incidence of the program. Empirical analysis of two data sets suggest that changes in employers' costs of workers' compensation insurance are largely shifted to employees in the form of lower wages. In addition, higher insurance costs are found to have a negative but statistically insignificant effect on employment. The implied elasticity of labor demand from our results is about -.50.

An essential function for the ATR-Activation-Domain (AAD) of TopBP1 in mouse development and cellular senescence

ATR activation is dependent on temporal and spatial interactions with partner proteins. In the budding yeast model, three proteins – Dpb11TopBP1, Ddc1Rad9 and Dna2 - all interact with and activate Mec1ATR. Each contains an ATR activation domain (ADD) that interacts directly with the Mec1ATR:Ddc2ATRIP complex. Any of the Dpb11TopBP1, Ddc1Rad9 or Dna2 ADDs is sufficient to activate Mec1ATR in vitro. All three can also independently activate Mec1ATR in vivo: the checkpoint is lost only when all three AADs are absent. In metazoans, only TopBP1 has been identified as a direct ATR activator. Depletion-replacement approaches suggest the TopBP1-AAD is both sufficient and necessary for ATR activation. The physiological function of the TopBP1 AAD is, however, unknown. We created a knock-in point mutation (W1147R) that ablates mouse TopBP1-AAD function. TopBP1-W1147R is early embryonic lethal. To analyse TopBP1-W1147R cellular function in vivo, we silenced the wild type TopBP1 allele in heterozygous MEFs. AAD inactivation impaired cell proliferation, promoted premature senescence and compromised Chk1 signalling following UV irradiation. We also show enforced TopBP1 dimerization promotes ATR-dependent Chk1 phosphorylation. Our data suggest that, unlike the yeast models, the TopBP1-AAD is the major activator of ATR, sustaining cell proliferation and embryonic development

The Impact of Income on the Weight of Elderly Americans

This paper estimates the impact of income on the body weight and clinical weight classification of elderly Americans using a natural experiment that led otherwise identical retirees to receive significantly different Social Security payments based on their year of birth. We estimate models of instrumental variables using data from the National Health Interview Surveys and find no significant effect of income on weight. The confidence intervals rule out even moderate effects of income on weight and on the probability of being underweight or obese, especially for men. For example, they indicate that the income elasticity of body mass index is not greater in absolute value than 0.06 for men or 0.14 for women

Human matrix metalloproteinases: An ubiquitarian class of enzymes involved in several pathological processes

Human matrix metalloproteinases (MMPs) belong to the M10 family of the MA clan of endopeptidases. They are ubiquitarian enzymes, structurally characterized by an active site where a Zn(2+) atom, coordinated by three histidines, plays the catalytic role, assisted by a glutamic acid as a general base. Various MMPs display different domain composition, which is very important for macromolecular substrates recognition. Substrate specificity is very different among MMPs, being often associated to their cellular compartmentalization and/or cellular type where they are expressed. An extensive review of the different MMPs structural and functional features is integrated with their pathological role in several types of diseases, spanning from cancer to cardiovascular diseases and to neurodegeneration. It emerges a very complex and crucial role played by these enzymes in many physiological and pathological processes

The Drosophila 7SK snRNP and the essential role of dHEXIM in development

Regulation of the positive transcription elongation factor, P-TEFb, plays a major role in controlling mammalian transcription and this is accomplished in part by controlled release of P-TEFb from the 7SK snRNP that sequesters the kinase in an inactive state. We demonstrate here that a similar P-TEFb control system exists in Drosophila. We show that an RNA previously suggested to be a 7SK homolog is, in fact, associated with P-TEFb, through the action of a homolog of the human HEXIM1/2 proteins (dHEXIM). In addition, a Drosophila La related protein (now called dLARP7) is shown to be the functional homolog of human LARP7. The Drosophila 7SK snRNP (d7SK snRNP) responded to treatment of cells with P-TEFb inhibitors and to nuclease treatment of cell lysates by releasing P-TEFb. Supporting a critical role for the d7SK snRNP in Drosophila development, dLARP7 and dHEXIM were found to be ubiquitously expressed throughout embryos and tissues at all stages. Importantly, knockdown of dHEXIM was embryonic lethal, and reduction of dHEXIM in specific tissues led to serious developmental defects. Our results suggest that regulation of P-TEFb by the d7SK snRNP is essential for the growth and differentiation of tissues required during Drosophila development

Employer Health Insurance Mandates and the Risk of Unemployment

Employer health insurance mandates form the basis of many health care reform proposals. Proponents make the case that they will increase insurance, while opponents raise the concern that low-wage workers will see offsetting reductions in their wages and that in the presence of minimum wage laws some of the lowest wage workers will become unemployed. We construct an estimate of the number of workers whose wages are so close to the minimum wage that they cannot be lowered to absorb the cost of health insurance, using detailed data on wages, health insurance, and demographics from the Current Population Survey (CPS). We find that 33 percent of uninsured workers earn within $3 of the minimum wage, putting them at risk of unemployment if their employers were required to offer insurance. Assuming an elasticity of employment with respect to minimum wage increase of -0.10, we estimate that 0.2 percent of all full-time workers and 1.4 percent of uninsured full-time workers would lose their jobs because of a health insurance mandate. Workers who would lose their jobs are disproportionately likely to be high school dropouts, minority, and female. This risk of unemployment should be a crucial component in the evaluation of both the effectiveness and distributional implications of these policies relative to alternatives such as tax credits, Medicaid expansions, and individual mandates, and their broader effects on the well-being of low-wage workers.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73099/1/j.1540-6296.2008.00133.x.pd

HEXIM1 targets a repeated GAUC motif in the riboregulator of transcription 7SK and promotes base pair rearrangements

7SK snRNA, an abundant RNA discovered in human nucleus, regulates transcription by RNA polymerase II (RNAPII). It sequesters and inhibits the transcription elongation factor P-TEFb which, by phosphorylation of RNAPII, switches transcription from initiation to processive elongation and relieves pauses of transcription. This regulation process depends on the association between 7SK and a HEXIM protein, neither isolated partner being able to inhibit P-TEFb alone. In this work, we used a combined NMR and biochemical approach to determine 7SK and HEXIM1 elements that define their binding properties. Our results demonstrate that a repeated GAUC motif located in the upper part of a hairpin on the 5′-end of 7SK is essential for specific HEXIM1 recognition. Binding of a peptide comprising the HEXIM Arginine Rich Motif (ARM) induces an opening of the GAUC motif and stabilization of an internal loop. A conserved proline-serine sequence in the middle of the ARM is shown to be essential for the binding specificity and the conformational change of the RNA. This work provides evidences for a recognition mechanism involving a first event of induced fit, suggesting that 7SK plasticity is involved in the transcription regulation