Vaccine microarray patch self-administration: An innovative approach to improve pandemic and routine vaccination rates.

The high-density microprojection array patch (HD-MAP) is a novel vaccine delivery system with potential for self-administered vaccination. HD-MAPs provide an alternative to needle and syringe (N&S) vaccination. Additional advantages could include reduced cold-chain requirements, reduced vaccine dose, reduced vaccine wastage, an alternative for needle phobic patients and elimination of needlestick injuries. The drivers and potential benefits of vaccination by self-administering HD-MAPs are high patient acceptance and preference, higher vaccination rates, speed of roll-out, cost-savings, and reduced sharps and environmental waste. The HD-MAP presents a unique approach in pandemic preparedness and routine vaccination of adults. It could alleviate strain on the healthcare workforce and allows vaccine administration by minimally-trained workers, guardian or subjects themselves. Self-vaccination using HD-MAPs could occur in vaccination hubs with supervision, at home after purchasing at the pharmacy, or direct distribution to in-home settings. As a result, it has the potential to increase vaccine coverage and expand the reach of vaccines, while also reducing labor costs associated with vaccination. Key challenges remain around shifting the paradigm from medical professionals administrating vaccines using N&S to a future of self-administration using HD-MAPs. Greater awareness of HD-MAP technology and improving our understanding of the implementation processes required for adopting this technology, are critical factors underpinning HD-MAP uptake by the public.

Optically guided neuronal growth at near infrared wavelengths.

Recent work has indicated the potential of light to modify the growth of neuronal cells. The two reported studies however, were performed on two independent optical set-ups and on differing cell-types at different temperatures and at different wavelengths. Therefore, it is unknown whether there is a bias for this effect to a particular wavelength which would have implications for the mechanisms for this phenomenon. Localized changes in heat have been suggested as a possible mechanism for this process, but as yet there is no direct experimental evidence to support or discount this hypothesis. In this paper, we report the first direct comparison on one cell type, of this process at two near infra-red wavelengths: 780 nm and 1064 nm using exactly the same beam shape. We show that light at both wavelengths is equally effective in initiating this process. We also directly measure the temperature rise caused by each wavelength in water and its absorption in the cellular medium. The recorded temperature rises are insufficient to change the rate of actin polymerization.

Photoporation and cell transfection using a violet diode laser.

The introduction and subsequent expression of foreign DNA inside living mammalian cells (transfection) is achieved by photoporation with a violet diode laser. We direct a compact 405 nm laser diode source into an inverted optical microscope configuration and expose cells to 0.3 mW for 40 ms. The localized optical power density of ~1200 MW/m2 is six orders of magnitude lower than that used in femtosecond photoporation (~104 TW/m2). The beam perforates the cell plasma membrane to allow uptake of plasmid DNA containing an antibiotic resistant gene as well as the green fluorescent protein (GFP) gene. Successfully transfected cells then expand into clonal groups which are used to create stable cell lines. The use of the violet diode laser offers a new and simple poration technique compatible with standard microscopes and is the simplest method of laser-assisted cell poration reported to date.

Provider network instability: implications for choice, costs and continuity of care.

Many health care issues of greatest concern to consumers-including provider choice, costs and continuity of care-depend on health plans' ability to maintain adequate networks of hospitals, physicians and other caregivers. When providers drop out of plan networks, consumers may suddenly face the choice of changing caregivers or paying more for out-of-network care. Network instability is increasingly common in health care markets across the country and can arise from health plan-provider contract disputes and provider organization insolvencies. This Issue Brief, which is based on the Center for Studying Health System Change's (HSC) 2000-01 site visits to 12 nationally representative communities, examines this growing trend and the implications for consumers, including diminished choice and higher costs.

Provider organizations at risk: a profile of major risk-bearing intermediaries, 1999.

Provider organizations have evolved to function as intermediaries between managed care plans and individual providers. These organizations assume much financial risk and care management responsibilities. We profile the characteristics of these organizations in markets across the country. The data, taken from a 1999 telephone survey of sixty-four entities in twenty markets and from interviews conducted during site visits to four markets, highlight the youth of many of these organizations, the large financial risk and functional responsibilities they bear, and the mixed views they hold about the health plans they contract with in terms of their willingness to delegate the authority, support, and collaboration that accompany risk. Policymakers need to evaluate what this means for oversight of managed care.

HMO provider networks in Medicare+Choice: comparing Medicare and commercial lines of business.

The Medicare+Choice (M+C) program was intended to expand choice of managed care plans for Medicare beneficiaries. In the past few years, the opposite has occurred as many participating HMOs reduced Medicare service areas or withdrew from the program. This paper presents findings from a study of the provider networks of 85 HMOs that were participating in M+C in 1999. The study shows that provider networks serving Medicare enrollees are usually similar to those developed for HMOs' commercial line of business, but when they are different, Medicare provider networks are smaller. Most HMOs also had at least some problems maintaining their Medicare provider networks. These findings have implications for the future of the Medicare+Choice program and Medicare enrollees' access to health care.

Do HMOs make a difference?

The growth of managed care has prompted questions about the effects of health maintenance organizations (HMOs) on consumers. This Issue Brief reports the results from a large national study of the privately insured population. No detectable difference was found between HMOs and other types of insurance in the use of three costly services--inpatient care, emergency room use and surgeries--and differences in reports of unmet need or delayed care are negligible. Differences for other measures pose a trade-off for consumers: HMOs provide more primary and preventive services and lower financial barriers to care, but they provide less specialist care and raise administrative barriers to care. In addition, patients in HMOs report less satisfaction, less trust in physicians and lower ratings of physician visits. These findings have implications for the current policy debate about managed care.

Isolation and characterization of monoclonal antibodies specific for protein conformational epitopes present in prostate-specific membrane antigen (PSMA).

Prostate-specific membrane antigen (PSMA) is a 750-amino acid glycoprotein highly expressed in malignant prostate tissues. PSMA reacts with the murine monoclonal antibody 7E11.C5, whose binding epitope has been mapped to the N-terminal of the protein distributed on the cytoplasmic side of the plasma membrane. We have developed murine monoclonal antibodies specific for extracellular epitopes of PSMA. Three of these antibodies--1G9, 3C6, and 4D4--display distinct binding properties consistent with their recognition of conformational epitopes within native PSMA. Results indicate this panel of antibodies binds to native full-length PSMA, but not to fusion proteins containing portions of the linear sequence of the protein. Antibody binding is greatly reduced upon heat denaturation of native PSMA, and these antibodies do not detect PSMA by Western blot. Immunoprecipitation experiments demonstrate the ability of each to bind to full-length PSMA as well as PSM', a form of the protein missing the first 57 amino acids. These results indicate each antibody is specific for an epitope within the extracellular domain, a region spanning residues 44-750. Flow cytometric experiments indicate strong specific binding to live LNCaP cells. Antibody inhibition studies demonstrate that these antibodies recognize at least two distinct epitopes. Taken together, the results demonstrate that these antibodies are specific for native protein conformational epitopes within the extracellular domain. Their properties, in particular strong binding to live cancer cells, make them ideal candidates that are clearly superior to linear sequence epitope specific antibodies for in vivo applications.

Compact and efficient Nd:YVO 4 laser that generates a tunable single-frequency green output.

We demonstrate 250 mW of single-frequency 532-nm output from a simple intracavity-doubled Nd:YVO(4) laser, pumped with 1.2 W from a fiber-coupled diode laser. The laser can be frequency chirped smoothly over approximately 17 GHz while maintaining a single-frequency green output of greater than 200 mW. A short Fabry-Perot cavity is used, and single-frequency operation is enforced by means of a birefringent filter that utilizes the birefringence of both the KTP doubling crystal and the Nd:YVO(4) laser crystal with polarization-dependent loss from a glass Brewster plate combined with polarization-dependent gain from the laser crystal.

Do HMOs make a difference? Consumer assessments of health care.

This study examines the effects of health maintenance organizations (HMOs) on consumer assessments of health care among the privately insured, nonelderly population. After controlling for population and location differences, the study finds that HMO enrollees are less likely than those in non-HMOs to be satisfied with their care, to rate their last medical visit highly, and to express trust in their physicians. One exception is a finding of little or no statistically significant difference between HMO and non-HMO enrollees in the likelihood of distrust that a physician may provide unnecessary services.

Current trends in health plan payment methods for the facility costs of outpatient care.

Outpatient hospital and ambulatory care services represent the fastest growing part of national health care expenditures. Until recently, most health plans reimbursed providers' outpatient facility costs on the basis of billed charges. Some health plans have now implemented prospective payment systems with incentives for limiting the volume of ambulatory care services. Findings from 1997 telephone interviews with senior managers in national managed care companies and local health plans reveal that recent reforms at some health plans have been generally incremental, building on existing systems, but use of outpatient prospective payment systems by private health plans is still rare. However, health plan managers expect continued reforms in the future as experience is gained with new payment systems such as those based on the Ambulatory Patient Groups case mix grouping method.

Self-Q-switched Nd:YVO4 microchip lasers.

We have observed giant pulses from cw pumped, monolithic Nd:YVO(4) microchip lasers, several hundred times the cw level, with pulse lengths less than 2 ns, which cannot be accounted for by conventional gain switching. These pulses occur as the second longitudinal mode starts to oscillate and can be described by the inclusion of gain-related effects in the formation of a stable cavity.

A national survey of the arrangements managed-care plans make with physicians.

BACKGROUND: Despite the growth of managed care in the United States, there is little information about the arrangements managed-care plans make with physicians. METHODS: In 1994 we surveyed by telephone 138 managed-care plans that were selected from 20 metropolitan areas nationwide. Of the 108 plans that responded, 29 were group-model or staff-model health maintenance organizations (HMOs), 50 were network or independent-practice-association (IPA) HMOs, and 29 were preferred-provider organizations (PPOs). RESULTS: Respondents from all three types of plan said they emphasized careful selection of physicians, although the group or staff HMOs tended to have more demanding requirements, such as board certification or eligibility. Sixty-one percent of the plans responded that physicians' previous patterns of costs or utilization of resources had little influence on their selection; 26 percent said these factors had a moderate influence; and 13 percent said they had a large influence. Some risk sharing with physicians was typical in the HMOs but rare in the PPOs. Fifty-six percent of the network or IPA HMOs used capitation as the predominant method of paying primary care physicians, as compared with 34 percent of the group or staff HMOs and 7 percent of the PPOs. More than half the HMOs reported adjusting payments according to utilization or cost patterns, patient complaints, and measures of the quality of care. Ninety-two percent of the network or IPA HMOs and 61 percent of the group or staff HMOs required their patients to select a primary care physician, who was responsible for most referrals to specialists. About three quarters of the HMOs and 31 percent of the PPOs reported using studies of the outcomes of medical care as part of their quality-improvement programs. CONCLUSIONS: Managed-care plans, particularly HMOs, have complex systems for selecting, paying, and monitoring their physicians. Hybrid forms are common, and the differences between group or staff HMOs and network or IPA HMOs are less extensive than is commonly assumed.

Behind the curve: a critical assessment of how little is known about arrangements between managed care plans and physicians.

Extraordinary growth in managed care arrangements over the past decade has been both widely praised and criticized. Proponents and critics agree that the nature of medical practice is being profoundly altered by this growth, even if they cannot articulate the direction and consequences of this change. We explore the roots of this uncertainty by examining the available evidence on critical features of the arrangements managed care plans currently have with affiliated physicians. Our approach is to review and synthesize the literature in several key substantive areas from a broad range of sources. We found that existing knowledge is dated, derived form a limited subset of plans, inattentive to important structural differences between plans, and responsive to a very narrow set of issues poorly reflecting the range of medical practice and change introduced by managed care. We highlight key questions of interest and the knowledge gaps critical to address so that policy and management decisions can both reflect and be informed on these issues that define the arrangements managed care plans make with physicians and ultimately influence medical practice.