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Purpose: The incidence of head and neck squamous cell carcinomas (HNSCC) associated with human papillomavirus (HPV) infection has increased over the past decades in the United States. We aimed at examining the global impact of HPV-associated HNSCC and whether the established key role of mTOR activation in HNSCC is also observed in HPV+ HNSCC lesions, thereby providing novel treatment options for HPV-associated HNSCC patients.Experimental Design: An international HNSCC tissue microarray (TMA) was used to analyze the expression of p16INK4A, a surrogate for HPV infection, and Akt-mTOR pathway activation. Results were confirmed in a large collection of HPV− and HPV+ HNSCC cases and in a cervical cancer (CCSCC) TMA. Observations were validated in HNSCC and CCSCC-derived cell lines, which were xenografted into immunodeficient mice for tumorigenesis assays.Results: Approximately 20% of all HNSCC lesions could be classified as HPV+, irrespective of their country of origin. mTOR pathway activation was observed in most HPV+ HNSCC and CCSCC lesions and cell lines. The preclinical efficacy of mTOR inhibition by rapamycin and RAD001 was explored in HPV+ HNSCC and CCSCC tumor xenografts. Both mTOR inhibitors effectively decreased mTOR activity in vivo and caused a remarkable decrease in tumor burden. These results emphasize the emerging global impact of HPV-related HNSCCs and indicate that the activation of the mTOR pathway is a widespread event in both HPV− and HPV-associated HNSCC and CCSCC lesions.Conclusions: The emerging results may provide a rationale for the clinical evaluation of mTOR inhibitors as a molecular targeted approach for the treatment of HPV-associated malignancies. Clin Cancer Res; 18(9); 2558–68. ©2012 AACR.

Individuals with autism spectrum disorder (ASD) have comorbid epilepsy at much higher rates than the general population, and about 30% will be refractory to medication. Patients with drug-resistant epilepsy (DRE) should be referred for surgical evaluation, yet many with ASD and DRE are not resective surgical candidates. The aim of this study was to examine the response of this population to the responsive neurostimulator (RNS) System.This multicenter study evaluated patients with ASD and DRE who underwent RNS System placement. Patients were included if they had the RNS System placed for 1 year or more. Seizure reduction and behavioral outcomes were reported. Descriptive statistics were used for analysis.Nineteen patients with ASD and DRE had the RNS System placed at 5 centers. Patients were between the ages of 11 and 29 (median 20) years. Fourteen patients were male, whereas five were female. The device was implanted from 1 to 5 years. Sixty-three percent of all patients experienced a50% seizure reduction, with 21% of those patients being classified as super responders (seizure reduction90%). For the super responders, two of the four patients had the device implanted for2 years. The response rate was 70% for those in whom the device was implanted for2 years. Improvements in behaviors as measured by the Clinical Global Impression Scale-Improvement scale were noted in 79%. No complications from the surgery were reported.Based on the authors' experience in this small cohort of patients, the RNS System seems to be a promising surgical option in people with ASD-DRE.

When a firm offers health benefits to workers, it exposes the firm to the risk of making payments when workers get sick. A firm can either pay health expenses out of its general assets, keeping the risk inside the firm, or it can purchase insurance, shifting the risk outside the firm. We analyze the firm’s decision to manage this risk. Using data on the insurance decisions of publicly-traded firms, we find that smaller firms, firms with more investment opportunities, and firms that face a convex tax schedule are more likely to hedge the risk of health benefit payments. Health risk is common to all firms, making this application an important contribution to understanding firms’ hedging decisions. Additionally, we reveal new and important determinants of the hedging decision relative to regulatory regimes. We also show that hedging health risk mitigates investment-cash flow sensitivities.

The standard Medicare Part D drug insurance contract is non-linear—with reduced subsidies in a coverage gap—resulting in a dynamic purchase problem. We consider enrolees who arrived near the gap early in the year and show that they should expect to enter the gap with high probability, implying that, under a benchmark model with neoclassical preferences, the gap should impact them very little. We find that these enrolees have flat spending in a period before the doughnut hole and a large spending drop in the gap, providing evidence against the benchmark model. We structurally estimate behavioural dynamic drug purchase models and find that a price salience model where enrolees do not incorporate future prices into their decision-making at all fits the data best. For a nationally representative sample, full price salience would decrease enrolee spending by 31%. Entirely eliminating the gap would increase insurer spending 27%, compared to 7% for generic-drug-only gap coverage.

Many markets maintain a nontrivial mix of both nonprofit and for-profit firms, particularly in health care industries such as hospice, nursing homes, and home health. What are the effects of coexistence vs. dominance of one ownership type? We show how the presence of both ownership types can lead to greater diversity in consumer types served, even if both firms merely profit-maximize. This is the case where firms serve consumers for multiple consumption durations, but where donations are part of a nonprofit firm objective function and happen after services have been provided. This finding is strengthened if the good or service has value beyond immediate consumption or the direct consumer. We show these predictions empirically in the hospice industry, using data containing over 90 percent of freestanding U.S. hospices, 2000-2008. Nonprofit and for-profit providers split the patient market according to length of stay, leading to a wider range of patients being served than in the absence of this coexistence.

Nonlinear pricing is prevalent in industries such as health care, public utilities, and telecommunications. However, this pricing scheme introduces bias into estimating elasticities for welfare analysis or policy changes. I develop a local elasticity estimation method that uses nonlinear price schedules to isolate consumers' expenditure choices from selection and simultaneity biases. This method improves over previous approaches by using commonly-available observational data and requiring only a single general monotonicity assumption. Using claims-level data on health insurance with two nonlinearities, I am able to measure two separate elasticities, and find that elasticity declines from − 0.26 to− 0.09 by the second nonlinearity. These estimates are then used to calculate moral hazard deadweight loss. This method enables estimation of many policies with nonlinear pricing which previous tools could not address.

Typhoid fever and shigellosis cause high morbidity and mortality worldwide, yet no anti- Shigella vaccine is currently available. However, to protect against typhoid fever, an approved vaccine, based on the attenuated Salmonella enterica serovar Typhi strain Ty21a is available. We have investigated Ty21a as a live oral vaccine vector for expression of heterologous foreign antigens to protect against other diseases (e.g. shigellosis, anthrax, and plague). Shigella LPS is a potent vaccine antigen for serotype-specific protection against Shigellae. We previously reported the construction of a Ty21a derivative expressing S. sonnei O-antigen by insertion of a large (∼12.5 kb) operon comprising the S. sonnei O-antigen biosynthetic genes into a targeted site within the Ty21a chromosome using modified λ red recombineering methods. In the current study, S. dysenteriae 1 O-antigen biosynthetic genes from 2 separate genetic loci, rfp and rfb were assembled and inserted into the Ty21a chromosome by λ red -mediated recombineering to construct strain Ty21a-Sd. To obtain a high level of heterologous LPS expression, the native upstream promoter was replaced with the constitutive lpp promoter, which resulted in Ty21a-Sdl with enhanced heterologous LPS expression. Both Ty21a-Sd and Ty21a-Sdl elicited significant serum antibody responses in mice against both Ty21a and this heterologous Shigella LPS, and conferred protection against virulent S. dysenteriae 1 challenge. This work represents progress toward the goal of a safe and effective vaccine against Shigella .

For-profit hospitals in California contract out services much more intensely than either private nonprofit or public hospitals. To explain why, we build a model in which the outsourcing decision is a trade-off between cost and control. Since nonprofit firms are more restricted in how they consume net revenues, they experience more rapidly diminishing value of a dollar saved, and they are less attracted to a low-cost but low-control outsourcing opportunity than a for-profit firm is. This difference is exaggerated in services where the benefits of controlling the details of production are particularly important but minimized when a fixed-cost shock raises the marginal value of a dollar of cost savings. We test these predictions in a panel of California hospitals, finding evidence for each and that the set of services that private non-profits are particularly interested in controlling (physician-intensive services) is very different from those than public hospitals are particularly interested in (labor-intensive services). These results suggest that a model of public or nonprofit make-or-buy decisions should be more than a simple relabeling of a model derived in the for-profit context.

When a firm offers health benefits to workers, it exposes the firm to the risk of making payments when workers get sick. A firm can either pay health expenses out of its general assets, keeping the risk inside the firm, or it can purchase insurance, shifting the risk outside the firm. We analyze the firm’s decision to manage this risk. Using data on the insurance decisions of publicly-traded firms, we find that smaller firms, firms with more investment opportunities, and firms that face a convex tax schedule are more likely to hedge the risk of health benefit payments. Health risk is common to all firms, making this application an important contribution to understanding firms’ hedging decisions. Additionally, we reveal new and important determinants of the hedging decision relative to regulatory regimes. We also show that hedging health risk mitigates investment-cash flow sensitivities.

For-profit hospitals in California contract out services much more intensely than either public hospitals or private nonprofit hospitals. To explain why, we build a model in which the outsourcing decision is a trade-off between net revenues and some nonmonetary benefit to the manager, which we call “bias” in the manner of production. Since nonprofit firms must consume profits indirectly, they trade off differently than for-profit firms. This difference is exaggerated in services where nonmonetary benefits are particularly important but minimized when the firm is hit with a fixed-cost shock. We test these predictions in a panel of California hospitals, finding evidence for each. These results suggest that a model of public or nonprofit make-or-buy decisions should be more than a simple relabeling of a model derived in the for-profit context.

For-profit hospitals in California contract out to a much greater extent than either public hospitals or private nonprofit hospitals. To explain why, we build a model in which the outsourcing decision is a trade-off between net revenues and “quality", any factor of interest to the hospital manager over-and-above its impact on net-revenues. Since nonprofit firms must consume profits indirectly through perquisites, they trade off differently from for-profit firms. This difference is exaggerated when “quality" is particularly important or the firm is hit with a favorable fixed-cost shock. We test these predictions in a panel of California hospitals, finding evidence for each. These results suggest that a model of public or nonprofit make-or-buy decisions should be more than a simple relabeling of a model derived in the for-profit context.

When a firm offers health benefits to workers, it exposes the firm to the risk of making payments when workers get sick. A firm can either pay health expenses out of its general assets, keeping the risk inside the firm, or it can purchase insurance, shifting the risk outside the firm. We analyze the firm's decision to manage this risk. Using data on the insurance decisions of publicly-traded firms, we find that smaller firms, firms with more investment opportunities, and firms that face a convex tax schedule are more likely to hedge the risk of health benefit payments. These financial characteristics explain more of the hedging decision relative to commonly-cited state insurance mandates. We also show that hedging health risk mitigates investment-cash flow sensitivities.

Nonlinear pricing is prevalent in industries such as health care, public utilities, and telecommunications. However, nonlinear pricing in these sectors causes bias when estimating elasticities for welfare analysis or policy changes. This paper develops a local elasticity estimation method that takes advantage of nonlinear price schedules to isolate consumers' expenditure choices from selection and simultaneity biases. This method improves over previous approaches because it uses commonly-available observational data and requires a single general monotonicity assumption. Using detailed claims-level health insurance data with two nonlinearities, this paper measures declining elasticities from -0.26 to -0.09 along initial expenditure ranges, in contrast to previous work which aggregates over a skewed spending distribution. These estimates are then used to calculate moral hazard deadweight loss. This method enables estimation on many policies with nonlinear pricing which previous tools could not address.

Theoretical models predict asymmetric information in health insurance markets may generate inefficient outcomes due to adverse selection and moral hazard. However, previous empirical research has found it difficult to disentangle adverse selection from moral hazard in health care. We empirically study this question by a using unique data set with confidential information from a large self-insured employer to estimate a structural model of the demand for health insurance and medical care. We propose a two-step semi-parametric estimation strategy that builds on the work on identification and estimation of auction models. We find significant evidence of moral hazard and adverse selection.

The failure of the dollar's depreciation to narrow the U.S. trade deficit has driven recent research showing that the transmission of exchange rate changes to import prices has declined sharply in industrial countries. Estimates presented in this study, however, suggest that "pass-through" to U.S. import prices has fallen only modestly, if at all, in the last decade. The authors argue that methodological changes in the collection of import data and the inclusion of commodity prices in pass-through models may have contributed to earlier findings of low pass-through rates.