Achievement of Target Gain Larger than Unity in an Inertial Fusion Experiment

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

Insights From Implementation Of A Community-Based Model For Collaborative Public Good Investing

Communities across the United States are looking for ways to reduce health inequities. Improving the social determinants of health (SDOH) is one fruitful pathway. In prior work we developed a financing model to incentivize and coordinate joint SDOH investments among local stakeholders, called the Collaborative Approach to Public Good Investments (CAPGI). A core thesis of our model is that at least some SDOH investments can be funded without reliance on philanthropic or government monies: Because they can produce value that flows to multiple organizations simultaneously, SDOH investments can be aligned with health organizations' self-interest. We describe our model's evolution in practice and synthesize insights drawn from our experiences providing technical assistance to three communities that have implemented CAPGI. Each community is unique, but we identified common themes related to governance processes and coalition dynamics that are relevant to any community trying to increase local, place-based investments in health.

Understanding who benefits most from cognitive rehabilitation for multiple sclerosis: A secondary data analysis

BACKGROUND

Up to 70% of people with multiple sclerosis (MS) experience cognitive difficulties. Cognitive rehabilitation is a type of therapy that helps manage cognitive problems.

OBJECTIVE

The Cognitive Rehabilitation for Attention and Memory in MS (CRAMMS) trial showed some evidence of effectiveness of cognitive rehabilitation in improving cognitive function, with some participants benefitting more than others. We therefore conducted a secondary analysis of the CRAMMS data to understand who benefits most.

METHODS

We grouped baseline data into four categories of possible predictors. We used regression models to identify specific factors/characteristics that could predict the likelihood that an individual will benefit from cognitive rehabilitation.

RESULTS

The models predicted whether a participant improved or did not improve in neuropsychological function following cognitive rehabilitation in up to 86% of participants. Results suggest that younger participants with medium to high education, diagnosed with relapsing-remitting multiple sclerosis (RRMS) and primary-progressive multiple sclerosis (PPMS) who have not experienced any recent relapses, with mild to moderate cognitive difficulties were most likely to benefit from cognitive rehabilitation.

CONCLUSION

We can predict which participants are most likely to demonstrate significant improvements in neuropsychological function following group-based cognitive rehabilitation. Clinically, this allows us to optimise limited neuropsychology resources by offering such cognitive rehabilitation to those most likely to benefit.

Trust in Health Care and Science: Toward Common Ground on Key Concepts

This essay summarizes key insights across the essays in the Hastings Center Report's special report "Time to Rebuild: Essays on Trust in Health Care and Science." These insights concern trust and trustworthiness as distinct concepts, competence as a necessary but not sufficient input to trust, trust as a reciprocal good, trust as an interpersonal as well as structural phenomena, the ethical impermissibility of seeking to win trust without being trustworthy, building and borrowing trust as distinct strategies, and challenges to trustworthiness posed by the contingent nature of science. Together, these insights stand to advance an area of research that we believe has been historically stymied by conceptual confusion and a long-standing insistence on treating trust as a purely instrumental good.

Business-nonprofit hybrid organizing: a dynamic approach to balancing benefits and costs

Introduction

Efforts to address complex public health challenges can benefit from cross-sector collaboration, while also fostering growing business sector engagement in promoting health equity. What form business-nonprofit collaboration should take, however, is a difficult question for managers and leaders. Hybrid organizational forms, which combine for-profit and nonprofit elements within a single organization in unconventional ways, offer an innovative and potentially promising approach. Yet, while existing typologies of cross-sector collaboration have identified hybrid forms at one end of a continuum of possible forms of collaboration, these typologies do not differentiate the diversity such hybrid forms may take, and the costs and benefits of these innovative hybrid forms are poorly understood. This leaves managers interested in promoting public health through business-nonprofit hybrid organizing with limited guidance about how to maximize potential merits while mitigating drawbacks.

Methods

We performed a qualitative comparative case study of three examples of business-nonprofit hybrid organizing. Data collection included 113 interviews with representatives from 42 organizations and observation of case study activities. We used thematic analysis within and across cases to characterize the form of hybrid organizing in each case and to examine benefits and costs of different forms for supporting initiatives.

Results

We identified two hybrid, collaborative forms - Appended and Blended forms. Each form had benefits and costs, the significance of which shifted over time contingent on changing strategic priorities and operating environments. Benefits and costs of particular forms become more or less important for establishing and sustaining initiatives under different conditions, requiring a dynamic view.

Discussion

No particular form of business-nonprofit hybrid organizing is inherently better than another. Optimizing hybrid organizing and ensuring resilient collaborations may mean allowing collaborative forms to evolve. Practitioners can manage tradeoffs between benefits and costs through an ongoing process of assessing the fit between a given collaborative form, strategic priorities, and relevant features of the operating environment. This dynamic view offers important insights for ensuring the resilience of business-nonprofit collaborative efforts to enhance public health.

Building resilient partnerships: How businesses and nonprofits create the capacity for responsiveness

Increasingly, businesses are eager to partner with nonprofit organizations to benefit their communities. In spite of good intentions, differences between nonprofit and business organizations can limit the ability of potential partnerships to respond to a changing economic and public health landscape. Using a retrospective, multiple-case study, we sought to investigate the managerial behaviors that enabled businesses and nonprofits to be themselves together in sustainable partnerships. We recruited four nonprofit-business partnerships in the Boston area to serve as cases for our study. Each was designed to address social determinants of health. We thematically analyzed qualitative data from 113 semi-structured interviews, 9 focus groups and 29.5 h of direct observations to identify organizational capacities that build resilient partnerships. Although it is common to emphasize the similarities between partners, we found that it was the acknowledgement of difference that set partnerships up for success. This acknowledgement introduced substantial uncertainty that made managers uncomfortable. Organizations that built the internal capacity to be responsive to, but not control, one another were able to derive value from their unique assets.

Review of Dranove and Burns, 2021. Big Med: Megaproviders and the High Cost of Health Care in America

David Dranove and Lawton Burn’s new collaboration Big Med: Megaproviders and the High Cost of Health Care in America provides readers with a comprehensive tutorial on consolidation in United States healthcare markets over the past 40 years. Although the book is most explicitly aimed at those who look around and wonder how we arrived at a healthcare landscape dominated by giants, anyone with a serious interest in the prices of U.S. healthcare will want to have this rigorous and timely treatment on their bookshelf.

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Do Health Care Organizations Have Legitimate Responsibilities beyond the Delivery of Health Care? Insights from Citizenship Theory

Many health care organizations made public commitments to become antiracist in the wake of George Floyd's murder. These actions raise questions about the appropriateness of health care's engagement in racial justice and social justice movements generally. We argue that health care organizations can be usefully thought of as having two roles: a functional role to care for the sick and a meta-role as an organizational citizen. Fulfilling the role of citizen may require participating in the pursuit of social justice, including efforts to achieve racial equity. The demands of these two roles will need to be balanced, but the role of organizational citizen has been largely ignored and merits serious attention.

Overlooked Potential of Business-Inclusive Networks to Amplify Anchoring Activity Impact

Mobilizing anchor institutions to promote community health and wellbeing is gaining prominence as an approach to systems change. Anchors are often conceptualized as large, locally rooted, nonprofits that leverage their resources for local benefit. However, existing literature underemphasizes 2 opportunities to enhance the systemic impact of anchoring activity: (1) coordinated action by anchoring networks that include diverse, multi-level stakeholders-a hallmark of health promotion and (2) the potential contributions of the business sector to anchoring networks. Our perspective describes the significance of both for amplifying anchoring impact and identifies critical questions for enabling action.

Healthcare lobbying on upstream social determinants of health in the US

Healthcare stakeholders are increasingly investing to address social determinants of health (SDOH) as they seek to improve health outcomes and reduce total healthcare costs in their communities. Policy heavily shapes SDOH, and healthcare lobbying on SDOH issues may offer large impacts through positive policy change. Federal lobbying disclosures from the ten highest spending health insurance and healthcare provider organizations and related associations between 2015 and 2019 were reviewed to identify lobbying reported on the salient SDOH issues, defined based on the Accountable Health Communities Model health-related social needs screening tool. Five of the organizations reported lobbying on some SDOH issues, including financial strain, employment, food insecurity, and interpersonal safety, but none reported lobbying on other issues, such as non-healthcare-related employment, housing instability, transportation, or education. Lobbying has been a missed opportunity for addressing SDOH. Healthcare organizations have the opportunity to expand their lobbying on upstream SDOH policy issues to increase the impact of their SDOH strategy and further improve population health.

Memory rehabilitation for people with multiple sclerosis

BACKGROUND

Problems with cognition, particularly memory, are common in people with multiple sclerosis (MS) and can affect their ability to complete daily activities and can negatively affect quality of life. Over the last few years, there has been considerable growth in the number of randomised controlled trials (RCTs) of memory rehabilitation in MS. To guide clinicians and researchers, this review provides an overview of the effectiveness of memory rehabilitation for people with MS.

OBJECTIVES

To determine whether people with MS who received memory rehabilitation compared to those who received no treatment, or an active control showed better immediate, intermediate, or longer-term outcomes in their: 1. memory functions, 2. other cognitive abilities, and 3. functional abilities, in terms of activities of daily living, mood, and quality of life.

SEARCH METHODS

We searched CENTRAL which includes Clinicaltrials.gov, World Health Organization (The Whoqol) International Clinical Trials Registry Portal, Embase and PubMed (MEDLINE), and the following electronic databases (6 September 2020): CINAHL, LILACS, the NIHR Clinical Research Network Portfolio database, The Allied and Complementary Medicine Database, PsycINFO, and CAB Abstracts.

SELECTION CRITERIA

We selected RCTs or quasi-RCTs of memory rehabilitation or cognitive rehabilitation for people with MS in which a memory rehabilitation treatment group was compared with a control group. Selection was conducted independently first and then confirmed through group discussion. We excluded studies that included participants whose memory deficits were the result of conditions other than MS, unless we could identify a subgroup of participants with MS with separate results.

DATA COLLECTION AND ANALYSIS

Eight review authors were involved in this update in terms of study selection, quality assessment, data extraction and manuscript review. We contacted investigators of primary studies for further information where required. We conducted data analysis and synthesis in accordance with Cochrane methods. We performed a 'best evidence' synthesis based on the methodological quality of the primary studies included. Outcomes were considered separately for 'immediate' (within the first month after completion of intervention), 'intermediate' (one to six months), and 'longer-term' (more than six months) time points.

MAIN RESULTS

We added 29 studies during this update, bringing the total to 44 studies, involving 2714 participants. The interventions involved various memory retraining techniques, such as computerised programmes and training on using internal and external memory aids. Control groups varied in format from assessment-only groups, discussion and games, non-specific cognitive retraining, and attention or visuospatial training. The risk of bias amongst the included studies was generally low, but we found eight studies to have high risk of bias related to certain aspects of their methodology. In this abstract, we are only reporting outcomes at the intermediate timepoint (i.e., between one and six months). We found a slight difference between groups for subjective memory (SMD 0.23, 95% CI 0.11 to 0.35; 11 studies; 1045 participants; high-quality evidence) and quality of life (SMD 0.30, 95% CI 0.02 to 0.58; 6 studies; 683 participants; high-quality evidence) favoring the memory rehabilitation group. There was a small difference between groups for verbal memory (SMD 0.25, 95% CI 0.11 to 0.40; 6 studies; 753 participants; low-quality evidence) and information processing (SMD 0.27, 95% CI 0.00 to 0.54; 8 studies; 933 participants; low-quality evidence), favoring the memory rehabilitation group.  We found little to no difference between groups for visual memory (SMD 0.20, 95% CI -0.11 to 0.50; 6 studies; 751 participants; moderate-quality evidence), working memory (SMD 0.16, 95% CI -0.09 to 0.40; 8 studies; 821 participants; moderate-quality evidence), or activities of daily living (SMD 0.06, 95% CI -0.36 to 0.24; 4 studies; 400 participants; high-quality evidence).  AUTHORS' CONCLUSIONS: There is evidence to support the effectiveness of memory rehabilitation on some outcomes assessed in this review at intermediate follow-up. The evidence suggests that memory rehabilitation results in between-group differences favoring the memory rehabilitation group at the intermediate time point for subjective memory, verbal memory, information processing, and quality of life outcomes, suggesting that memory rehabilitation is beneficial and meaningful to people with MS. There are differential effects of memory rehabilitation based on the quality of the trials, with studies of high risk of bias inflating (positive) outcomes. Further robust, large-scale, multi-centre RCTs, with better quality reporting, using ecologically valid outcome assessments (including health economic outcomes) assessed at longer-term time points are still needed to be certain about the effectiveness of memory rehabilitation in people with MS.

Should a Healthcare System Facilitate Racially Concordant Care for Black Patients?

Addressing racial disparities in health outcomes is an urgent priority for many health care organizations, leading health care managers to explore the potential for organization-level interventions to yield substantive health gains. In recent literature, it is suggested that Black patients who are treated by Black physicians may achieve superior health outcomes in some settings. In this case discussion, we consider a case in which a medical director considers implementing a voluntary program to promote racially concordant care for Black patients. Commentators consider the precedent for such a program, both in current informal care networks and 20th century medical history, as well as the burden such a program may place on Black physicians and the risks of reducing patients' intersectional identities to be solely about race. A subset of commentators suggest that these risks are mitigated by the voluntary nature of the program, whereas others offer caution about relying solely on Black physicians to remedy health disparities. Others view multiple paths as morally defensible but emphasize the need for managers to take proactive steps to communicate and evaluate their choices in the face of such a complex social challenge.

Increasing the structural boundary of quasiracemate formation: 4-substituted naphthylamides

Spatially larger naphthylamides than previously reported diarylamides promote greater structural variance of substituents during the pairwise assembly of quasienantiomers.

The Challenge of Mutual Disclosure in Global Health Partnerships

Institutional partnerships in global health, those contractual relationships involving institutions from the Global North and the Global South for purposes of public health enhancement and academic research, often fail to live up to the expectations held by all parties involved. The literature generally argues that inequities are the main concern in global health partnerships. We break with previous analyses by proposing a conceptual model to explain the frequently poor quality of the relationships based on aspects of sameness between the parties, or what we call symmetries in the relationship. We suggest that certain symmetries in positioning, fears and misgivings, and behavior inhibit critical disclosure of relevant information that could improve the effectiveness of the partnership. We propose seven essential elements of building trust in these relationships, and we recommend an incremental approach that treats trust as both a desired outcome and a necessary process that must be developed slowly over time to enhance a partnership's success.

How Do We Fund Flourishing? Maybe Not through Health Care

The health policy community has a growing interest in the impact of nonmedical determinants of health, such as housing, nutrition, and social supports, on both health outcomes and costs. This interest has been spurred by the Affordable Care Act's emphasis on prevention, Robert Wood Johnson's grant-making focus on a Culture of Health, and an uptick of research demonstrating the potential returns to health care from investments in social services. Much of this policy-making, grant making, and research has focused on older Americans. The direct policy implications of this strategy can be elusive. It has become clear that more than medicine will be necessary to improve older Americans' health status. Real improvement likely requires the development of additional social service offerings, including housing that is accessible to people with disabilities, Meals on Wheels-type nutrition supports, and transportation. But who should bear the costs and control the finances associated with these programs? In this essay, I explore the question of how policy-makers should consider financing nonmedical investments in older Americans' health. As the reader will recognize, I stop short of arguing for what will work. Rather, I identify the strands of an emerging strategy-namely, for health care dollars to be diverted into social service programming-and offer several cautions. It may be that policy-makers still wish to continue down this path, but my hope is that this essay will allow them to so with greater attention to the risks and unintended consequences of that strategy.

Spending on social and public health services and its association with homicide in the USA: an ecological study

OBJECTIVE

To examine whether state-level spending on social and public health services is associated with lower rates of homicide in the USA.

DESIGN

Ecological study.

SETTING

USA.

PARTICIPANTS

All states in the USA and the District of Columbia for which data were available (n=42).

PRIMARY OUTCOME MEASURE

Homicide rates for each state were abstracted from the US Department of Justice Federal Bureau of Investigation's Uniform Crime Reporting.

RESULTS

After adjusting for potential confounding variables, we found that every $10 000 increase in spending per person living in poverty was associated with 0.87 fewer homicides per 100 000 population or approximately a 16% decrease in the average homicide rate (estimate=-0.87, SE=0.15, p<0.001). Furthermore, there was no significant effect in the quartile of states with the highest percentages of individuals living in poverty but significant effects in the quartiles of states with lower percentages of individuals living in poverty.

CONCLUSIONS

Based on our findings, spending on social and public health services is associated with significantly lower homicide rates at the state level. Although we cannot infer causality from this research, such spending may provide promising avenues for homicide reduction in the USA, particularly among states with lower levels of poverty.

Geospatial analysis of emergency department visits for targeting community-based responses to the opioid epidemic

The opioid epidemic in the United States carries significant morbidity and mortality and requires a coordinated response among emergency providers, outpatient providers, public health departments, and communities. Anecdotally, providers across the spectrum of care at Massachusetts General Hospital (MGH) in Boston, MA have noticed that Charlestown, a community in northeast Boston, has been particularly impacted by the opioid epidemic and needs both emergency and longer-term resources. We hypothesized that geospatial analysis of the home addresses of patients presenting to the MGH emergency department (ED) with opioid-related emergencies might identify “hot spots” of opioid-related healthcare needs within Charlestown that could then be targeted for further investigation and resource deployment. Here, we present a geospatial analysis at the United States census tract level of the home addresses of all patients who presented to the MGH ED for opioid-related emergency visits between 7/1/2012 and 6/30/2015, including 191 visits from 100 addresses in Charlestown, MA. Among the six census tracts that comprise Charlestown, we find a 9.5-fold difference in opioid-related ED visits, with 45% of all opioid-related visits from Charlestown originating in tract 040401. The signal from this census tract remains strong after adjusting for population differences between census tracts, and while this tract is one of the higher utilizing census tracts in Charlestown of the MGH ED for all cause visits, it also has a 2.9-fold higher rate of opioid-related visits than the remainder of Charlestown. Identifying this hot spot of opioid-related emergency needs within Charlestown may help re-distribute existing resources efficiently, empower community and ED-based physicians to advocate for their patients, and serve as a catalyst for partnerships between MGH and local community groups. More broadly, this analysis demonstrates that EDs can use geospatial analysis to address the emergency and longer-term health needs of the communities they are designed to serve.

American health care paradox-high spending on health care and poor health

BACKGROUND

For decades, US taxpayers have been lamenting the high cost of health care. Since the mid-1980s, Americans have had double-digit spending on health care. Despite this investment, Americans are less healthy than their European and Scandinavian counterparts across an array of health measures.

AIM

We sought to explore how inadequate attention to the social, behavioral and environmental determinants of health may contribute to the American health care paradox of high health care spending and poor health outcomes.

DESIGN

Mixed methods.

METHODS

We report previous findings related from a 10-year analysis of national-level health and social service spending and health outcome data from the Organization of Economic and Cooperation and Development (OECD). We also put forth case studies representing different socioeconomic strata to illustrate the relationship between health care and social service spending and health.

RESULTS

Although the US spending more of its GDP on health care than any other country, it is not a high spender when one sums spending on both health care and social services. The U.S. however has the lowest ratio of our social service spending to health care spending in the OECD, and countries with lower ratios on average have worse health outcomes. Cases from diverse socioeconomic strata demonstrate how limited attention to the social determinants of health can result in extremely high health care costs and poor health outcomes.

CONCLUSIONS

Greater investment in addressing the social, behavioral and environmental determinants of health may foster better health without accelerating health care costs in America.

Leveraging the Social Determinants of Health: What Works?

We summarized the recently published, peer-reviewed literature that examined the impact of investments in social services or investments in integrated models of health care and social services on health outcomes and health care spending. Of 39 articles that met criteria for inclusion in the review, 32 (82%) reported some significant positive effects on either health outcomes (N = 20), health care costs (N = 5), or both (N = 7). Of the remaining 7 (18%) studies, 3 had non-significant results, 2 had mixed results, and 2 had negative results in which the interventions were associated with poorer health outcomes. Our analysis of the literature indicates that several interventions in the areas of housing, income support, nutrition support, and care coordination and community outreach have had positive impact in terms of health improvements or health care spending reductions. These interventions may be of interest to health care policymakers and practitioners seeking to leverage social services to improve health or reduce costs. Further testing of models that achieve better outcomes at less cost is needed.

Reconsidering Samuel: A Mental Health Caretaker at a Ghanaian Prayer Camp

This essay is intended to challenge popular and academic narratives of prayer camps in Ghana as being inherently inhumane. It is based on two years of Master's thesis research and six trips to one prayer camp in particular, where I observed the daily routines of the camp and interviewed staff who care for people with mental illness. I aim to contextualize what is currently known about patients and staff at Ghanaian prayer camps within Ghana's broader social, political, religious, and medical landscapes. To do so, I call upon my own experience interacting with one caretaker in particular: Samuel.

Management Matters: A Leverage Point for Health Systems Strengthening in Global Health

Despite a renewed focus in the field of global health on strengthening health systems, inadequate attention has been directed to a key ingredient of high-performing health systems: management. We aimed to develop the argument that management - defined here as the process of achieving predetermined objectives through human, financial, and technical resources - is a cross-cutting function necessary for success in all World Health Organization (WHO) building blocks of health systems strengthening. Management within health systems is particularly critical in low-income settings where the efficient use of scarce resources is paramount to attaining health goals. More generally, investments in management capacity may be viewed as a key leverage point in grand strategy, as strong management enables the achievement of large ends with limited means. We also sought to delineate a set of core competencies and identify key roles to be targeted for management capacity building efforts. Several effective examples of management interventions have been described in the research literature. Together, the existing evidence underscores the importance of country ownership of management capacity building efforts, which often challenge the status quo and thus need country leadership to sustain despite inevitable friction. The literature also recognizes that management capacity efforts, as a key ingredient of effective systems change, take time to embed, as new protocols and ways of working become habitual and integrated as standard operating procedures. Despite these challenges, the field of health management as part of global health system strengthening efforts holds promise as a fundamental leverage point for achieving health system performance goals with existing human, technical, and financial resources. The evidence base consistently supports the role of management in performance improvement but would benefit from additional research with improved methodological rigor and longer-time horizon investigations. Meanwhile, greater emphasis on management as a critical element of global health efforts may open new and sustainable avenues for advancing health systems performance.

Comparative analyses of tooth wear in free-ranging and captive wild equids

REASONS FOR PERFORMING STUDY

Captive breeding has played a crucial role in the conservation of threatened equid species. Grazing ruminants and rhinoceros in captivity have less abrasion-dominated tooth wear than their free-ranging conspecifics, with potential negative consequences for their health. However, a similar study on wild equids in captivity is missing.

OBJECTIVES

The aim was to establish if different tooth wear patterns are exhibited by free-ranging and captive equids.

STUDY DESIGN

Cross-sectional study of museum specimens comparing free-ranging and captive equids.

METHODS

Dental casts of maxillary cheek teeth of 228 museum specimens (122 from free-ranging and 106 from captive individuals) of 7 wild equid species were analysed using the extended mesowear method. Although teeth showing specific abnormalities were not scored, the presence of focal overgrowths (hooks) of the rostral premolars (106, 206) was recorded.

RESULTS

Captive Equus ferus przewalskii, E. grevyi, E. hemionus, E. quagga boehmi and E. zebra hartmannae have less abrasion-dominated tooth wear on their premolars than their free-ranging conspecifics (P<0.001). Fewer differences were exhibited between populations in the molars. No differences were exhibited in the distal cusp of the molars (110, 210) between populations, except in a small sample of E. kiang. Captive equids exhibited more homogeneous wear along the tooth row whereas free-ranging equids exhibited a tooth wear gradient, with more abrasion on premolars than molars. There were more rostral hooks on the premolars (106, 206) in the captive than the free-ranging population (P = 0.02).

CONCLUSIONS

Captive equids did experience less abrasion-dominated tooth wear than their free-ranging conspecifics, but the differences in tooth wear were less pronounced than those between captive and free-ranging wild ruminant and rhinoceros species. This indicates that feeding regimes for captive equids deviate less from natural diets than those for captive ruminants and rhinoceros but that factors leading to hook formation, in particular feeding height, should receive special attention. The Summary is available in Chinese - see Supporting information.

A model for scale up of family health innovations in low-income and middle-income settings: a mixed methods study

BACKGROUND

Many family health innovations that have been shown to be both efficacious and cost-effective fail to scale up for widespread use particularly in low-income and middle-income countries (LMIC). Although individual cases of successful scale-up, in which widespread take up occurs, have been described, we lack an integrated and practical model of scale-up that may be applicable to a wide range of public health innovations in LMIC.

OBJECTIVE

To develop an integrated and practical model of scale-up that synthesises experiences of family health programmes in LMICs.

DATA SOURCES

We conducted a mixed methods study that included in-depth interviews with 33 key informants and a systematic review of peer-reviewed and grey literature from 11 electronic databases and 20 global health agency web sites.

STUDY ELIGIBILITY CRITERIA, PARTICIPANTS AND INTERVENTIONS

We included key informants and studies that reported on the scale up of several family health innovations including Depo-Provera as an example of a product innovation, exclusive breastfeeding as an example of a health behaviour innovation, community health workers (CHWs) as an example of an organisational innovation and social marketing as an example of a business model innovation. Key informants were drawn from non-governmental, government and international organisations using snowball sampling. An article was excluded if the article: did not meet the study's definition of the innovation; did not address dissemination, diffusion, scale up or sustainability of the innovation; did not address low-income or middle-income countries; was superficial in its discussion and/or did not provide empirical evidence about scale-up of the innovation; was not available online in full text; or was not available in English, French, Spanish or Portuguese, resulting in a final sample of 41 peer-reviewed articles and 30 grey literature sources.

STUDY APPRAISAL AND SYNTHESIS METHODS

We used the constant comparative method of qualitative data analysis to extract recurrent themes from the interviews, and we integrated these themes with findings from the literature review to generate the proposed model of scale-up. For the systematic review, screening was conducted independently by two team members to ensure consistent application of the predetermined exclusion criteria. Data extraction from the final sample of peer-reviewed and grey literature was conducted independently by two team members using a pre-established data extraction form to list the enabling factors and barriers to dissemination, diffusion, scale up and sustainability.

RESULTS

The resulting model-the AIDED model-includes five non-linear, interrelated components: (1) assess the landscape, (2) innovate to fit user receptivity, (3) develop support, (4) engage user groups and (5) devolve efforts for spreading innovation. Our findings suggest that successful scale-up occurs within a complex adaptive system, characterised by interdependent parts, multiple feedback loops and several potential paths to achieve intended outcomes. Failure to scale up may be attributable to insufficient assessment of user groups in context, lack of fit of the innovation with user receptivity, inability to address resistance from stakeholders and inadequate engagement with user groups.

LIMITATIONS

The inductive approach used to construct the AIDED model did not allow for simultaneous empirical testing of the model. Furthermore, the literature may have publication bias in which negative studies are under-represented, although we did find examples of unsuccessful scale-up. Last, the AIDED model did not address long-term, sustained use of innovations that are successfully scaled up, which would require longer-term follow-up than is common in the literature.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

Flexible strategies of assessment, innovation, development, engagement and devolution are required to enable effective change in the use of family health innovations in LMIC.

Social stress alters expression of large conductance calcium-activated potassium channel subunits in mouse adrenal medulla and pituitary glands

Large conductance calcium-activated potassium (BK) channels are very prominently expressed in adrenal chromaffin and many anterior pituitary cells, where they shape intrinsic excitability complexly. Stress- and sex-steroids regulate alternative splicing of Slo-alpha, the pore-forming subunit of BK channels, and chronic behavioural stress has been shown to alter Slo splicing in tree shrew adrenals. In the present study, we focus on mice, measuring the effects of chronic behavioural stress on total mRNA expression of the Slo-alpha gene, two key BK channel beta subunit genes (beta2 and beta4), and the 'STREX' splice variant of Slo-alpha. As a chronic stressor, males of the relatively aggressive SJL strain were housed with a different unfamiliar SJL male every 24 h for 19 days. This 'social-instability' paradigm stressed all individuals, as demonstrated by reduced weight gain and elevated corticosterone levels. Five quantitative reverse transcriptase-polymerase chain assays were performed in parallel, including beta-actin, each calibrated against a dilution series of its corresponding cDNA template. Stress-related changes in BK expression were larger in mice tested at 6 weeks than 9 weeks. In younger animals, Slo-alpha mRNA levels were elevated 44% and 116% in the adrenal medulla and pituitary, respectively, compared to individually-housed controls. beta2 and beta4 mRNAs were elevated 162% and 194% in the pituitary, but slightly reduced in the adrenals of stressed animals. In the pituitary, dominance scores of stressed animals correlated negatively with alpha and beta subunit expression, with more subordinate individuals exhibiting levels that were three- to four-fold higher than controls or dominant individuals. STREX variant representation was lower in the subordinate subset. Thus, the combination of subunits responding to stress differs markedly between adrenal and pituitary glands. These data suggest that early stress will differentially affect neuroendocrine cell excitability, and call for detailed analysis of functional consequences.

New strategy for the analysis of phenotypic marker antigens in brain tumor-derived neurospheres in mice and humans

OBJECT

Brain tumor stem cells (TSCs) hypothetically drive the malignant phenotype of glioblastoma multiforme (GBM), and evidence suggests that a better understanding of these TSCs will have profound implications for treating gliomas. When grown in vitro, putative TSCs grow as a solid sphere, making their subsequent characterization, particularly the cells within the center of the sphere, difficult. Therefore, the purpose of this study was to develop a new method to better understand the proteomic profile of the entire population of cells within a sphere.

METHODS

Tumor specimens from patients with confirmed GBM and glioma models in mice were mechanically and enzymatically dissociated and grown in traditional stem cell medium to generate neurospheres. The neurospheres were then embedded in freezing medium, cryosectioned, and analyzed with immunofluorescence.

RESULTS

By sectioning neurospheres as thinly as 5 mum, the authors overcame many of the problems associated with immunolabeling whole neurospheres, such as antibody penetration into the core of the sphere and intense background fluorescence that obscures the specificity of immunoreactivity. Moreover, the small quantity of material required and the speed with which this cryosectioning and immunolabeling technique can be performed make it an attractive tool for the rapid assessment of TSC character.

CONCLUSIONS

This study is the first to show that cryosectioning of neurospheres derived from glioma models in mice and GBM in humans is a feasible method of better defining the stem cell profile of a glioma.

Toxicity and bioconcentration potential of the agricultural pesticide endosulfan in phytoplankton and zooplankton

Agricultural pesticide runoff in southeastern coastal regions of the United States is a critical issue. Bioconcentration of pesticides by phytoplankton and zooplankton at the base of the aquatic food web may increase the persistence of pesticides in aquatic ecosystems and cause effects at higher trophic levels. This study examined the toxicity of a widely used agricultural pesticide, endosulfan, to Pseudokirchneriella subcapitatum (freshwater green alga) and Daphnia magna (freshwater cladoceran). We then investigated the potential of both plankton species to sequester endosulfan from their surrounding media. We also assessed the degree to which endosulfan is accumulated by D. magna via food (endosulfan-contaminated P. subcapitatum). A 96-h growth rate EC50 of 427.80 microg/L endosulfan was determined for P. subcapitatum, whereas a 24-h immobilization EC50 of 366.33 microg/L endosulfan was determined for D. magna. The 5-h EC50s for filtration and ingestion in D. magna were 165.57 microg/L and 166.44 microg/L, respectively. An average bioconcentration factor (BCF) of 2,682 was determined for P. subcapitatum exposed to 100 microg/L endosulfan for 16 h. An average BCF of 3,278 was determined for D. magna in a 100 microg/L endosulfan water-only exposure. There was negligible uptake of endosulfan by D. magna feeding on contaminated algae in clean water (BCF approximately 0). Different proportions of parent isomers (endosulfan I and II) and the primary degradation product (endosulfan sulfate) were detected among treatments. Endosulfan was rapidly accumulated and concentrated from water by P. subcapitatum and D. magna neonates. Endosulfan contained in phytoplankton, however, was not bioaccumulated by zooplankton. These findings may prove useful in assessing ecosystem risk, because uptake from the water column appears to be the dominant route for bioconcentration of endosulfan by zooplankton.

Noninvasive blood pressure performance: a reproducible method for quantifying motion artifact tolerance in oscillometry

Motion artifact tends to degrade oscillometric noninvasive blood pressure measurement (NIBP) accuracy and other aspects of performance (measurement time, patient comfort, false-positive readings). Medical personnel generally have not fully appreciated the extent of these degradations, in part because NIBP provides no waveform display to allow visualization of artifact disruption (unlike the electrocardiography (ECG) and pulse oximetry (SpO2) patient channels). More importantly, the magnitude and frequency of NIBP errors has also gone unappreciated because the auditory noise produced by transport vibration prevents accurate quantification of NIBP accuracy by the traditional auscultatory method. To overcome these problems, a commercially available NIBP simulator was modified to permit the superimposition of repeatable motion artifact waveforms from a function generator onto known patient blood pressure profiles available in the NIBP simulator. The superimposed artifact waveforms had been collected under transport conditions. This methodology enabled comparisons between artifact-free NIBP readings, on the one hand, and artifact-contaminated readings on the other. Monitors under test were subjected to multiple combinations of patient and artifact profiles. Measurement errors were expressed as a percent deviation of the artifact-contaminated readings from the expected (artifact-free) readings. Statistical analyses of the data compared the performance of the different monitor types with nonparametric tests of inference (Kruskal-Wallis H test, Mann-Whitney U test, and chi-squared test). These analyses demonstrated statistically significant differences in performance including accuracy, yield (incidence of values within various error categories), retries, measurement time, and false-positive readings under artifact-only conditions. The method further demonstrated that the monitor using ECG synchronization to filter motion artifact achieved statistically and clinically significant improvements in accuracy without compromising clinical expectations for measurement time. This approach provided a reproducible and quantifiable method by which to assess and differentiate the artifact tolerance of different NIBP technologies.

Oxygen isotopes and the moon-forming giant impact

We have determined the abundances of 16O, 17O, and 18O in 31 lunar samples from Apollo missions 11, 12, 15, 16, and 17 using a high-precision laser fluorination technique. All oxygen isotope compositions plot within +/-0.016 per mil (2 standard deviations) on a single mass-dependent fractionation line that is identical to the terrestrial fractionation line within uncertainties. This observation is consistent with the Giant Impact model, provided that the proto-Earth and the smaller impactor planet (named Theia) formed from an identical mix of components. The similarity between the proto-Earth and Theia is consistent with formation at about the same heliocentric distance. The three oxygen isotopes (delta17O) provide no evidence that isotopic heterogeneity on the Moon was created by lunar impacts.

Memory training for children with Down syndrome

One well-established fact concerning cognitive and language development in individuals with Down syndrome is that working memory is particularly poor, with auditory working memory worse than visual working memory. Working memory serves the functions of control, regulation, and active maintenance of information and is critical in daily complex cognitive activities. Thus, there is a strong need to find effective and practical interventions targeted at improving working memory in individuals with Down syndrome. The present paper reviews research on rehearsal training and concludes that it can be used successfully to increase working memory in individuals with Down syndrome. However, there are still questions about whether auditory working memory can be improved reliably, whether improvement can be maintained over the long term, and whether improvement exists beyond any effect of increased attention. We describe our in-progress study which addresses these concerns.

Symptom management in older primary care patients: feasibility of an experimental, written self-disclosure protocol

BACKGROUND

Distress-driven symptoms are prevalent among older primary care patients and account for a large percentage of office visits and increased medical costs. An experimental written self-disclosure protocol has been shown to reduce symptoms and use of health care services in healthy adults. Written self-disclosure as a method for reducing symptoms has not been evaluated in the primary care setting.

OBJECTIVE

To evaluate the feasibility of adapting an experimental written self-disclosure protocol for the primary care setting.

DESIGN

Randomized, single-blind feasibility study.

SETTING

University-based geriatric and internal medicine primary care clinics.

PATIENTS

45 patients 66 years of age or older without a psychiatric diagnosis.

INTERVENTION

Three 20-minute writing sessions focusing on distressing experiences (in the intervention group) or health behaviors (in the control group).

MEASUREMENTS

The feasibility outcomes were patient recruitment, protocol logistics, and patient and provider satisfaction. The clinical outcomes were somatic and distress symptoms, health care utilization, and associated costs.

RESULTS

One third of patients screened were recruited; 96% of patients recruited completed the protocol. Clinic contact time was an average of 55 minutes per patient. Patients and providers reported high levels of satisfaction with the protocol. Reductions in symptoms were minimal for both groups. Use of outpatient services and associated costs decreased in both groups, but the reduction was twice as great in the treatment group as in the control group.

CONCLUSIONS

Findings support the feasibility of implementing the protocol as a primary care intervention.

Diphenyl sulfoxides as selective antagonists of the muscarinic M2 receptor

Structure activity studies on [4-(phenylsulfonyl)phenyl]methylpiperazine led to the discovery of 4-cyclohexyl-alpha-[4-[[4-methoxyphenyl(S)-sufinyl]phenyl]-1-pi perazineacetonitrile, 1, an M2 selective muscarinic antagonist. Affinity at the cloned human M2 receptor was 2.7 nM; the M1/M2 selectivity is 40-fold.

Diphenylsulfone muscarinic antagonists: piperidine derivatives with high M2 selectivity and improved potency

Piperidine analogues of our previously described piperazine muscarinic antagonists are described. Piperidine analogues show a distinct structure-activity relationship (SAR) that differs from comparable piperazines. Compounds with high selectivity and improved potency for the M2 receptor have been identified. The lead compound, 12b, increases acetylcholine release in vivo. Compounds of this class may be useful for the treatment of cognitive disorders such as Alzheimer's disease (AD).

Host gene regulation during coxsackievirus B3 infection in mice: assessment by microarrays

Host genetic responses that characterize enteroviral myocarditis have not yet been determined. The injurious and inflammatory process in heart muscle may reflect host responses of benefit to the virus and ultimately result in congestive heart failure and dilated cardiomyopathy. On the other hand, host responses within the myocardium may secure the host against acute or protracted damage. To investigate the nature of modified gene expression in comparison with normal tissue, mRNA species were assessed in myocardium using cDNA microarray technology at days 3, 9, and 30 after infection. Of 7000 clones initially screened, 169 known genes had a level of expression significantly different at 1 or more postinfection time points as compared with baseline. The known regulated genes were sorted according to their functional groups and normalized expression patterns and, subsequently, interpreted in the context of viremic, inflammatory, and healing phases of the myocarditic process.

Cost-effectiveness of the conventional papanicolaou test with a new adjunct to cytological screening for squamous cell carcinoma of the uterine cervix and its precursors

OBJECTIVE

To estimate costs and outcomes of conventional annual Papanicolaou (Pap) test screening compared with biennial Pap test plus speculoscopy (PPS) screening for cervical neoplasms.

DESIGN

A Markov model compared cost-effectiveness and outcomes of annual Pap tests with biennial PPS. The model includes direct costs of screening, diagnostic testing, and treatment for squamous intraepitheial lesions and invasive cancers; indirect costs (eg, lost productivity because of cervical cancer); and newer management practices, including human papillomavirus DNA testing.

PATIENTS

Women aged 18 to 64 years.

INTERVENTION

Screening for cervical neoplasms with either annual Pap smear test or biennial PPS.

MAIN OUTCOME MEASURE

Marginal cost per life-year gained.

RESULTS

The probability of women having squamous intraepithelial lesions, cervical cancer, or death from cervical cancer was lower among women undergoing PPS biennially. A total of 12 additional days of life per woman was gained with biennial PPS during the 47-year model period. Total average cumulative direct medical costs per patient were $1419 for biennial PPS compared with $1489 for annual Pap tests. Total costs, including direct medical costs and indirect costs, were $2185 for PPS compared with $3179 for Pap tests alone. Increased savings and patient outcomes were observed in high-risk populations.

CONCLUSION

Our simulations indicate that biennial screening with PPS is expected to provide cost savings for women older than 18 years compared with annual Pap test screening, especially for those in high-risk populations.

Whiskers amiss, a new vibrissae and hair mutation near the Krt1 cluster on mouse chromosome 11

Whiskers amiss (wam) is a new spontaneous recessive mutation in the SELH/Bc strain of mice that causes a phenotype of askew, sometimes kinked or curled, breakable whiskers and disheveled-appearing body hair, apparently owing to disoriented guard hairs. Heterozygotes on three genetic backgrounds are indistinguishable from normal. Using informative SSLPs in the F2 generation after crosses to two normal strains, we have mapped wam to the region of the type I keratin cluster on Chromosome (Chr) 11, within an approximately 6-cM segment according to the current Mouse Genome Database (MGD) map position of flanking SSLPs. Although several other hair mutations also map to the Krt1 region (Re, Rim3, Bdai, Bsk), none has a hair and whisker phenotype similar to that of wam, and, because all are transmitted as dominants, interpretable complementation tests could not be done. Scabbing and tissue loss occur on the rims of the pinnae and tail tip in some aging wam homozygotes, suggesting that wam may be an animal model of a genetic ectodermal disorder. The SELH/Bc strain background appears to have an unusually high rate of spontaneous mutation; wam is the sixth mutation to be described.

Preparation and storage characteristics of white cell-reduced high-concentration platelet concentrates collected by anapheresis system for transfusions in utero

BACKGROUND

Important concerns with regard to in utero platelet transfusions are avoidance of volume overload and the immunomodulatory effects of residual white cells (WBCs). This study evaluated a modification of a leukocyte-reduction system (LRS, Spectra, COBE BCT) for apheresis, which collects high-concentration WBC-reduced platelets (HCPs) for in utero transfusion.

STUDY DESIGN AND METHODS

The LRS procedure was modified by running the platelet collection pump at specified low flow rates (Q(col)) for the first part of the procedure, collecting HCPs by gently purging them from the LRS chamber into a designated collection bag and then restoring the original LRS procedure settings to collect a second standard apheresis platelet concentrate (PC). Two centers carried out 32 procedures. Platelet yield, residual WBCs, and in vitro platelet function studies were evaluated.

RESULTS

Platelet concentrations in 60 mL of HCPs were predictable according to Q(col) (r(2) = 0.735). HCP yields varied from 0.9 to 3.2 x 10(11), depending on the desired final platelet concentrations in 60 mL, with an overall average of 1. 92 x 10(11) (n = 32). Apheresis PCs had a mean platelet yield of 2.9 x 10(11) (1.3-4.4 x 10(11), n = 20) and 3.9 x 10(11) (2.2-5.8 x 10(11), n = 12) at concentrations of 1.3 x 10(12) per L for single-needle and dual- needle procedures, respectively. Median WBC counts were 5.6 x 10(3) for HCPs and 2.0 x 10(4) for apheresis PCs, with >99 percent expected to be less than 1 x 10(6). HCP in vitro characteristics were equivalent to those of apheresis PCs at 24 hours after collection. In vitro performance declined over storage as a function of HCP yield. HCP pH at 22(o)C was maintained at a level of >6.2 for more than 3 days for yields >1.6 x 10(11), less than 2 days for yields 1.6 to 2.2 x 10(11), and less than 24 hours for yields >2.2 x 10(11). HCPs showed good in vitro characteristics and could be stored for 1 to 3 days, depending on the total number of platelets collected.

CONCLUSION

A standard apheresis PC and an HCP requiring no secondary processing can be collected with the Spectra LRS. The platelet concentration may be determined by clinical need. HCPs meet the requirements for components that are transfused in utero.

SCH 57790: a novel M2 receptor selective antagonist

As a decrease in cholinergic neurons has been observed in Alzheimer's Disease (AD), therapeutic approaches to AD include inhibition of acetylcholinesterase to increase acetylcholine levels. Evidence suggests that acetylcholine release in the CNS is modulated by negative feedback via presynaptic M2 receptors, blockade of which should provide another means of increasing acetylcholine release. Structure-activity studies of [4-(phenylsulfonyl)phenyl]methylpiperazines led to the synthesis of 4-cyclohexyl-alpha-[4-[[4-methoxyphenyl]sulfinyl]-phenyl]-1-piperazin eacetonitrile. This compound, SCH 57790, binds to cloned human M2 receptors expressed in CHO cells with an affinity of 2.78 nM; the affinity at M1 receptors is 40-fold lower. SCH 57790 is an antagonist at M2 receptors expressed in CHO cells, as the compound blocks the inhibition of adenylyl cyclase activity mediated by the muscarinic agonist oxotremorine. This compound should be useful in assessing the potential of M2 receptor blockade for enhancement of cognition.

The complete coding sequence of hepatitis C virus genotype 5a, the predominant genotype in South Africa

Hepatitis C virus (HCV) genotype 5a is the predominant genotype in southern Africa with a high prevalence amongst infected blood donors from areas in South Africa. We have determined the nucleotide sequence corresponding to the complete coding region of an HCV isolate, EUH1480, previously classified as genotype 5a, from an Edinburgh haemophiliac. The sequence contained a single open reading frame (ORF) coding for a polyprotein of 3014 amino acids. Comparison with the polyprotein sequences from other HCV genotypes, where the ORF varies from 3008 to 3037 amino acids, showed the observed variation in size was due to differences in lengths of the envelope 2 and the nonstructural 5A proteins. The sequence divergence of HCV genotype 5 ranged from 29.4% nucleotide differences (24.91% amino acid differences) compared with genotype 1c to 32.5% nucleotide differences (30.3% amino acid differences) compared with 2a. Phylogenetic analysis of the available full length nucleotide sequences showed EUH1480 to form a branch distinct from the other HCV types, confirming the classification of type 5a as a separate genotype.

Complete coding sequence of hepatitis C virus genotype 6a

Hepatitis C virus (HCV) genotype 6a is found in a restricted part of South East Asia, including Hong Kong, Macau and Vietnam. We determined the full length coding sequence of a type 6a isolate (EUHK2) obtained from a Hong Kong blood donor. The sequence of EUHK2 contained a single open reading frame coding for a polyprotein of 3018 amino acids, within the range of 3008 to 3037 for other HCV genotypes. The full length sequence of EUHK2 showed 30.3%-32.9% nucleotide (24.3%-29.4% amino acid) sequence divergence from genotypes 1-4, but only 27.7% (20.7% amino acid) divergence from JK046 ("type 11a"). These similarity values were intermediate between those of other HCV genotypes (minimum 28.4%) and between subtypes (maximum 25%). The close evolutionary relationship of EUHK2 with JK046 was further indicated by their grouping together by phylogenetic analysis.

X-ray digital imaging petrography of lunar mare soils: modal analyses of minerals and glasses

It is essential that accurate modal (i.e., volume) percentages of the various mineral and glass phases in lunar soils be used for addressing and resolving the effects of space weathering upon reflectance spectra, as well as for their calibration such data are also required for evaluating the resource potential of lunar minerals for use at a lunar base. However, these data are largely lacking. Particle-counting information for lunar soils, originally obtained to study formational processes, does not provide these necessary data, including the percentages of minerals locked in multi-phase lithic fragments and fused-soil particles, such as agglutinates. We have developed a technique for modal analyses, sensu stricto, of lunar soils, using digital imaging of X-ray maps obtained with an energy-dispersive spectrometer mounted on an electron microprobe. A suite of nine soils (90 to 150 micrometers size fraction) from the Apollo 11, 12, 15, and 17 mare sites was used for this study. This is the first collection of such modal data on soils from all Apollo mare sites. The abundances of free-mineral fragments in the mare soils are greater for immature and submature soils than for mature soils, largely because of the formation of agglutinitic glass as maturity progresses. In considerations of resource utilization at a lunar base, the best lunar soils to use for mineral beneficiation (i.e., most free-mineral fragments) have maturities near the immature/submature boundary (Is/FeO approximately or = 30), not the mature soils with their complications due to extensive agglutination. The particle data obtained from the nine mare soils confirm the generalizations for lunar soils predicted by L.A. Taylor and D.S. McKay (1992, Lunar Planet Sci. Conf. 23rd, pp. 1411-1412 [Abstract]).

Distribution of muscarinic receptor subtypes in rat brain from postnatal to old age

In an effort to understand the developmental changes in the distribution of muscarinic receptor subtypes (m1-m5), specific brain regions from juvenile (16-day-old), young (21-day-old) and adult (90-day-old) rats were analyzed using subtype-selective antibodies. These studies revealed significant age-dependent changes in the four brain regions examined. In cortex, an area associated with higher cognitive functions, significant increases of m2 and m4 receptors occurred between juvenile and adult rats. In the striatum, the level of m4 receptor increased with age whereas the m1, m2 and m3 receptors had reached mature levels within the first 16 days. Small but significant changes occurred in the cerebellum with a decrease in m1, m3 and m4 receptor subtypes. In contrast to other brain regions, the hippocampus displayed consistent expression levels of muscarinic receptor subtypes. Suggesting that this brain region, which is involved in the foundation of numerous neural networks, requires a full complement of muscarinic receptors at a very early age. Muscarinic receptors have been shown to be important in a number of behavioral activities, including learning and memory. The changes observed in the age-dependent expression of these receptors most likely play an important role in how acetylcholine produces its effects in vivo.

The expression of the proteins of equine herpesvirus 1 which share homology with herpes simplex virus 1 glycoproteins H and L

Several expression systems were used in studies aimed at characterizing the equine herpesvirus 1 (EHV-1) glycoprotein H and L homologues of HSV-1 (EHV-1 gH and gL) and the products were compared to the authentic proteins synthesized in virus infected cells. Using an in vitro transcription/translation system two gH species were detected (an unprocessed 89 kDa and a processed 116 kDa product). Three low molecular weight proteins were found in the case of gL (21.8 kDa, 22.9 kDa and 26.9 kDa) and these showed a slight reduction in mobility on the addition of microsomal membranes to the reactions. A gL fusion protein was produced in pGEX-2T, expression being confirmed by Western blotting using a gL-specific antiserum raised against a peptide incorporating the 13 carboxyl terminal amino acids of the protein. A gH specific peptide antiserum precipitated both gH and two smaller proteins from EHV-1 infected cells thought to be two forms of gL. Insect cells infected with gH or gL baculovirus recombinants were used to vaccinate C3H (H-2k) mice. Some protection against EHV-1 infection was conferred to the gH inoculated mice. The results will enable further studies on the importance of the gH and gL interaction in the pathogenesis of EHV-1 to be evaluated and their potential in contributing to a subunit vaccine to be assessed.

Thrombin receptor ligation and activated Rac uncap actin filament barbed ends through phosphoinositide synthesis in permeabilized human platelets

Cells respond to diverse external stimuli by polymerizing cytoplasmic actin, and recent evidence indicates that GTPases can specify where this polymerization takes place. Actin assembly in stimulated blood platelets occurs where sequestered monomers add onto the fast-growing (barbed) ends of actin filaments (F-actin), which are capped in the resting cells. We report that D3 and D4 polyphosphoinositides, Pl(4)P, Pl(4,5)P2, Pl(3,4)P2, and Pl(3,4,5)P3, uncap F-actin in resting permeabilized platelets. The thrombin receptor-activating peptide (TRAP), GTP, and GTP gamma S, but not GDP beta S, also uncap F-actin in permeabilized platelets. GDP beta S inhibits TRAP-induced F-actin uncapping, and Pl(4,5)P2 overcomes this inhibition. Constitutively active mutant Rac, but not Rho, activates uncapping of F-actin. Pl(4,5)P2-binding peptides derived from gelsolin inhibit F-actin uncapping by TRAP, Rac, and GTP gamma S. TRAP and Rac induce rapid Pl(4,5)P2 synthesis in permeabilized platelets. The findings establish a signaling pathway for actin assembly involving Rac in which the final message is phosphoinositide-mediated F-actin uncapping.

Felbamate, a novel antiepileptic drug, reverses N-methyl-D-aspartate/glycine-stimulated increases in intracellular Ca2+ concentration

Felbamate, 2-phenyl-1,3-propanediol dicarbamate, is a novel, orally active anticonvulsant that has recently been approved for the treatment of Lennox-Gastaut syndrome and partial onset seizures in the United States. Felbamate is active in a broad range of animal anticonvulsant tests. Although its mechanism of action has yet to be fully elucidated, felbamate appears to act by inhibiting the spread of seizures and elevating seizure threshold. One proposed mechanism of action for felbamate is via the NMDA receptor complex. Previous studies have demonstrated the ability of felbamate to inhibit glycine binding at the NMDA receptor complex. The present study examined the effects of felbamate on NMDA/glycine-stimulated increases in intracellular calcium (Ca2+) using cultured rat hippocampal neurons. The results of these experiments demonstrate that felbamate inhibits NMDA/glycine-stimulated increases in intracellular Ca2+ with a minimal effective concentration of 100 microM.