Effects of absolute levels of neighbourhood ethnic diversity vs. changes in neighbourhood diversity on prejudice: Moderation by individual differences in personality

This paper examines drivers of prejudicial attitudes among adults in the UK, focusing on the interaction between ethnic out-group size and personality traits. Leveraging data from the National Child Development Study (NCDS), we use two survey waves carried out in 2000 and 2008, just before and after the EU enlargement policy that drove a wave of immigration in the UK. We test the extent to which personality traits moderate the relationship between both absolute levels and changes in ethnic diversity at the local level, respectively, and prejudice. Key findings suggest that personality traits, in particular one's agreeableness, are important for conditioning how the proportion of non-white British in one's neighbourhood affects out-group attitudes. We observe a tendency towards polarisation in prejudicial attitudes between low-/high-agreeableness residents as their neighbourhoods become more diverse. These findings have important implications for theorising how contextual and individual characteristics jointly affect intergroup relations.

Individual and community social capital, mobility restrictions, and psychological distress during the COVID-19 pandemic: a multilevel analysis of a representative US survey

This paper explores the role of social capital in mitigating the mental health harms of social/mobility restrictions instigated in the wake of the COVID-19 pandemic. We test whether: (a) social capital continued to predict lower mental distress during the pandemic; and (b) whether social capital buffered (moderated) the harm of social/mobility restrictions on psychological distress. In addition, we test the level at which social capital mitigation effects operated, i.e., at the individual- and/or contextual-level. To do so, we apply multilevel models to three waves of the COVID-19 Household Impact Survey consisting of probability samples of U.S. adults (with the average interview completion rate of 93%). In a novel approach, we explore two modes of capturing contextual social capital: aggregated individual-level survey responses and independently measured social capital indices (SCIs). Findings show that at the individual level social capital was associated with lower psychological distress. It also buffered the harm of restrictions: increasing restrictions had a weaker effect on distress among individuals interacting with neighbors more frequently. Importantly, mitigating processes of contextual social capital appeared conditional on how it was measured. Using aggregated survey responses, contextual social capital had no direct effect on distress but exerted an additional buffering role: individuals in counties with higher average neighbor-interaction experienced a weaker impact of restrictions. Using the independent SCI measures, we found county social capital reduced distress. However, its negative effect on distress becomes increasingly weaker the more restrictions an individual reported: where individuals reported lower restrictions, higher county SCI reduced distress; however, where individuals reported higher restrictions, higher county SCI had no effect on distress. More restrictive environments thus cut individuals off from the benefits of higher county social capital as measured using the SCI.

MASP2 levels are elevated in thrombotic microangiopathies: association with microvascular endothelial cell injury and suppression by anti-MASP2 antibody narsoplimab

Involvement of the alternative complement pathway (AP) in microvascular endothelial cell (MVEC) injury characteristic of a thrombotic microangiopathy (TMA) is well documented. However, the role of the lectin pathway (LP) of complement has not been explored. We examined mannose-binding lectin associated serine protease (MASP2), the effector enzyme of the LP, in thrombotic thrombocytopenic purpura, atypical hemolytic uremic syndrome and post-allogeneic hematopoietic stem cell transplantation (alloHSCT) TMAs. Plasma MASP2 and terminal complement component sC5b-9 levels were assessed by enzyme-linked immunosorbent assay (ELISA). Human MVEC were exposed to patient plasmas, and the effect of the anti-MASP2 human monoclonal antibody narsoplimab on plasma-induced MVEC activation was assessed by caspase 8 activity. MASP2 levels were highly elevated in all TMA patients versus controls. The relatively lower MASP2 levels in alloHSCT patients with TMAs compared to levels in alloHSCT patients who did not develop a TMA, and a significant decrease in variance of MASP2 levels in the former, may reflect MASP2 consumption at sites of disease activity. Plasmas from 14 of the 22 TMA patients tested (64%) induced significant MVEC caspase 8 activation. This was suppressed by clinically relevant levels of narsoplimab (1·2 μg/ml) for all 14 patients, with a mean 65·7% inhibition (36.8-99.4%; P < 0·0001). In conclusion, the LP of complement is activated in TMAs of diverse etiology. Inhibition of MASP2 reduces TMA plasma-mediated MVEC injury in vitro. LP inhibition therefore may be of therapeutic benefit in these disorders.

COVID-19 restrictions and mental distress among American adults: evidence from Corona Impact Survey (W1 and W2)

BACKGROUND

The present study examines the impact of coronavirus-related restrictions on mental health among American adults, and how this relationship varies as a function of time and two measures of vulnerability (preexisting physical symptoms and job insecurity).

METHODS

We draw on data from two waves of Corona Impact Survey, which were fielded in late April and early of May 2020. Multilevel models were used to analyze the hierarchically nested data.

RESULTS

Experiencing coronavirus disease-2019 restrictions significantly raise mental distress. This association is stronger for individuals with preexisting health conditions and those who worry about job prospects. These findings hold with the inclusion of region-wave covariates (number of deaths, wave dummy and aggregate measure of restrictions). Finally, there is a cross-level interaction: the restriction-distress connection is more pronounced in the second wave of data.

CONCLUSIONS

Our research indicates that people who are more physically and/or financially vulnerable suffer more from the imposed restrictions, i.e. 'social isolation'. The mental health impact of coronavirus pandemic is not constant but conditional on the level of vulnerability.

The differing pathophysiologies that underlie COVID-19-associated perniosis and thrombotic retiform purpura: a case series

Background

There are two distinctive acral manifestations of COVID‐19 embodying disparate clinical phenotypes. One is perniosis occurring in mildly symptomatic patients, typically children and young adults; the second is the thrombotic retiform purpura of critically ill adults with COVID‐19.

Objectives

To compare the clinical and pathological profiles of these two different cutaneous manifestations of COVID‐19.

Methods

We compared the light microscopic, phenotypic, cytokine and SARS‐CoV‐2 protein and RNA profiles of COVID‐19‐associated perniosis with that of thrombotic retiform purpura in critical patients with COVID‐19.

Results

Biopsies of COVID‐19‐associated perniosis exhibited vasocentric and eccrinotropic T‐cell‐ and monocyte‐derived CD11c⁺, CD14⁺ and CD123⁺ dendritic cell infiltrates. Both COVID‐associated and idiopathic perniosis showed striking expression of the type I interferon‐inducible myxovirus resistance protein A (MXA), an established marker for type I interferon signalling in tissue. SARS‐CoV‐2 RNA, interleukin‐6 and caspase 3 were minimally expressed and confined to mononuclear inflammatory cells. The biopsies from livedo/retiform purpura showed pauci‐inflammatory vascular thrombosis without any MXA decoration. Blood vessels exhibited extensive complement deposition with endothelial cell localization of SARS‐CoV‐2 protein, interleukin‐6 and caspase 3; SARS‐CoV‐2 RNA was not seen.

Conclusions

COVID‐19‐associated perniosis represents a virally triggered exaggerated immune reaction with significant type I interferon signaling. This is important to SARS‐CoV‐2 eradication and has implications in regards to a more generalized highly inflammatory response. We hypothesize that in the thrombotic retiform purpura of critically ill patients with COVID‐19, the vascular thrombosis in the skin and other organ systems is associated with a minimal interferon response. This allows excessive viral replication with release of viral proteins that localize to extrapulmonary endothelium and trigger extensive complement activation.

Community disadvantage, inequalities in adolescent subjective well-being, and local social relations: The role of positive and negative social interactions

Studies identify the existence of inequalities in adolescent subjective well-being (SWB) across levels of community socio-economic disadvantage. One posited explanation is that community disadvantage harms SWB through undermining positive social relations among residents (often termed social capital). However, social relations can be both positive and negative; for example, social interactions between residents can be friendly or unfriendly, or involve being helped or harmed. Little work has explored negative social relations in communities and their impact on SWB. This study therefore examines the role that local negative social relations may play, alongside positive relations, in understanding inequalities in SWB across communities. Data are taken from a nationally representative survey of 16-17-year olds in England in 2015. Applying multilevel models, findings demonstrate that adolescents living in more disadvantaged communities exhibit lower SWB. In line with current theories, part of this association can be accounted for by weaker positive social relations: the results show that while positive local interactions are important for youth SWB (primarily via higher neighbour trust), young people in more disadvantaged communities report fewer local positive social interactions. However, the models also demonstrate that part of the negative association between community disadvantage and SWB is also accounted for by stronger negative social relations: the results show that negative local interactions are harmful for youth SWB (both directly, and indirectly via lower neighbour-trust), and young people in disadvantaged communities report more frequent negative local social interactions. Importantly, the negative indirect-effect of community disadvantage via increasing negative social interactions is almost twice as strong as the negative indirect-effect of disadvantage via reducing positive interactions. Taken together, community disadvantage appears to harm SWB not only by reducing positive relations but also increasing negative relations. These form dual, independent, social relations pathways through which community disadvantage affects SWB.

Youth Engagement, Positive Interethnic Contact, and 'Associational Bridges': A Quasi-Experimental Investigation of a UK National Youth Engagement Scheme

Affective interethnic ties are highly effective for improving out-group attitudes, especially during adolescence. Yet, young people face several obstacles to developing such ties in society. One potential means of fostering greater interethnic connectivity is through youth engagement: that is, formal, organized social participation in groups, clubs, or activities. However, little is still known about its effectiveness; especially for overcoming structural obstacles to contact in society, such as residential segregation. This study has two aims: to robustly examine whether youth engagement can build positive interethnic contact among young people; and, to perform the first systematic test of whether sites of engagement can act as “Associational Bridges”, providing greater opportunities for contact among youth from more segregated environments. To pursue these aims, the study exploited a unique data opportunity to perform a quasi-experimental analysis of a large-scale, nationally-implemented youth engagement scheme in the United Kingdom. The study uses pre-test/post-test data on N = 1371 participants (M_age = 16.7; 63% Female; 36% non-White) and N = 1946 propensity-score matched controls (M_age = 16.7; 62% Female; 36% non-White). Applying a (matched) difference-in-difference approach, the findings demonstrate that participation led to an increase in affective interethnic ties, which were evident at least 4–6 months after involvement had ended. Participation also had a stronger positive impact on youth from more residentially segregated areas: although joining the scheme with fewer interethnic ties, post-participation they reported just as many ties as their peers from less segregated areas. However, participation had no difference in effects for youth from more or less ethnically diverse areas. Youth engagement may thus be an effective tool for fostering positive contact; particularly among those from more segregated environments. However, attention should be paid to the design and recruitment practices of engagement programs to understand which structural barriers to contact in society they can overcome.

Countervailing contact: Community ethnic diversity, anti-immigrant attitudes and mediating pathways of positive and negative inter-ethnic contact in European societies

Inter-ethnic contact has long been held as a key means of ameliorating possible inter-group tensions and facilitating the integration of increasing immigrant populations into society. However, our understanding of the role of contact in this relationship may be limited due to the omission of contact-valence; that is, whether contact is experienced positively or negatively. This paper integrates the concept of contact-valence into the question of how increasing community diversity affects attitudes towards immigrants via inter-group contact, across Europe. We posit the existence of dual, mediating pathways of both positive and negative inter-group contact. Applying generalized structural equation models to data from the 2014 European Social Survey, we find that living in more diverse communities increases the frequency of positive inter-group contact but also negative inter-group contact. While the former is positively associated with inter-group attitudes the latter is negatively associated. Testing demonstrates that diversity exerts countervailing positive and negative indirect-effects on attitudes towards immigrants via processes of inter-group contact. Furthermore, while the net-effect of diversity on attitudes via contact is positive, attitudes amongst those experiencing more frequent negative contact become progressively worse. Increasing diversity therefore leads to a polarisation in attitudes towards immigration as a result of, and not due to a lack of, inter-group contact.

Wider-community Segregation and the Effect of Neighbourhood Ethnic Diversity on Social Capital: An Investigation into Intra-Neighbourhood Trust in Great Britain and London

Extensive research has demonstrated that neighbourhood ethnic diversity is negatively associated with intra-neighbourhood social capital. This study explores the role of segregation and integration in this relationship. To do so it applies three-level hierarchical linear models to two sets of data from across Great Britain and within London, and examines how segregation across the wider-community in which a neighbourhood is nested impacts trust amongst neighbours. This study replicates the increasingly ubiquitous finding that neighbourhood diversity is negatively associated with neighbour-trust. However, we demonstrate that this relationship is highly dependent on the level of segregation across the wider-community in which a neighbourhood is nested. Increasing neighbourhood diversity only negatively impacts neighbour-trust when nested in more segregated wider-communities. Individuals living in diverse neighbourhoods nested within integrated wider-communities experience no trust-penalty. These findings show that segregation plays a critical role in the neighbourhood diversity/trust relationship, and that its absence from the literature biases our understanding of how ethnic diversity affects social cohesion.

Ethnic Diversity, Inter-group Attitudes and Countervailing Pathways of Positive and Negative Inter-group Contact: An Analysis Across Workplaces and Neighbourhoods

This study advances the current literature investigating the relationship between contextual out-group exposure, inter-group attitudes and the role of inter-group contact. Firstly, it introduces the concept of contact-valence into this relationship; that is, whether contact is experienced positively or negatively. Secondly, it presents a comparative analysis of how processes of out-group exposure and frequency of (valenced) contact affect prejudice across both neighbourhoods and workplaces. Applying path analysis modelling to a nationally-representative sample of white British individuals in England, we demonstrate, across both contexts, that increasing out-group exposure is associated with higher rates of both positively- and negatively-valenced contact. This results in exposure exhibiting both positive and negative indirect associations with prejudice via more frequent inter-group mixing. These countervailing contact-pathways help explain how out-group exposure is associated with inter-group attitudes. In neighbourhoods, increasing numbers of individuals experiencing positive-contact suppress an otherwise negative effect of neighbourhood diversity (driven partly by increasing numbers of individuals reporting negative contact). Across workplaces the effect differs such that increasing numbers of individuals experiencing negative-contact suppress an otherwise positive effect of workplace diversity (driven largely by increasing numbers of individuals experiencing positive contact).

Doing good when times are bad: volunteering behaviour in economic hard times

This paper examines how the 2008-9 recession has affected volunteering behaviours in the UK. Using a large survey dataset, we assess the recession effects on both formal volunteering and informal helping behaviours. Whilst both formal volunteering and informal helping have been in decline in the UK since 2008, the size of the decline is significantly larger for informal helping than for formal volunteering. The decline is more salient in regions that experienced a higher level of unemployment during the recession and also in socially and economically disadvantaged communities. However, we find that a growing number of people who personally experienced financial insecurity and hardship do not explain the decline. We argue that the decline has more to do with community-level factors such as civic organizational infrastructure and cultural norms of trust and engagement than personal experiences of economic hardship.

(Dis)placing trust: the long-term effects of job displacement on generalised trust over the adult lifecourse

Increasing rates of job displacement (i.e. involuntary job loss from redundancy, downsizing, restructuring) have been suggested to be a key driver of declining macro-levels of generalised trust. This article undertakes the first test of how job displacement affects individuals' tendencies to (dis)trust over the adult lifecourse, using two-waves of the Great Britain National Child Development Study cohort data, on a sample of n=6840 individuals. Applying both lagged dependent variable logistic regression and two-wave change-score models, experiencing job displacement between the ages of 33 and 50 appears to significantly scar individuals' generalised trust, with depressed trust observable at least nine years after the event occurred. However, this effect is dependent on the value an individual places on work: the greater the attachment to employment the stronger the negative effect of displacement. A range of mediators, such as physical health, mental well-being, and personal efficacy, do not appear to account for the effect.

Effects of HIV infection and antiretroviral therapy with ritonavir on induction of osteoclast-like cells in postmenopausal women

SUMMARY

Ritonavir (RTV) is a commonly used antiretroviral associated with bone loss. We show that peripheral blood mononuclear cells (PBMCs) from human immunodeficiency virus (HIV)-positive women on RTV are more likely to differentiate into osteoclast-like cells when cultured with their own sera than PBMCs and sera from HIV- women or HIV+ on other antiretrovirals.

INTRODUCTION

RTV increases differentiation of human adherent PBMCs to functional osteoclasts in vitro, and antiretroviral regimens containing RTV have been associated with low bone mineral density (BMD) and bone loss.

METHODS

BMD, proresorptive cytokines, bone turnover markers (BTMs), and induction of osteoclast-like cells from adherent PBMCs incubated either with macrophage colony-stimulating factor (MCSF) and receptor activator of nuclear factor κB ligand (RANKL) or with autologous serum were compared in 51 HIV- and 68 HIV+ postmenopausal women.

RESULTS

BMD was lower, and serum proresorptive cytokines and BTMs were higher in HIV+ versus HIV- women. Differentiation of osteoclast-like cells from adherent PBMCs exposed to either MCSF/RANKL or autologous serum was greater in HIV+ women. Induction of osteoclast-like cells was greater from PBMCs exposed to autologous sera from HIV+ women on RTV-containing versus other regimens (172 ± 14% versus 110 ± 10%, p < 0.001). Serum-based induction of osteoclast-like cells from adherent PBMCs correlated with certain BTMs but not BMD.

CONCLUSIONS

HIV infection and antiretroviral therapy are associated with higher BTMs and increased differentiation of osteoclast-like cells from adherent PBMCs, especially in women on regimens containing RTV. HIV+ postmenopausal women receiving RTV may be at greater risk for bone loss.

Composition, concentration and deprivation: exploring their association with social cohesion among different ethnic groups in the UK

Although studies in the US have shown an association between the ethnic residential composition of an area and reports of decreased social cohesion among its residents, this association is not clear in the UK, and particularly for ethnic minority groups. The current study analyses a merged dataset from the 2005 and 2007 Citizenship Survey to assess the evidence for an association between social cohesion and ethnic residential concentration, composition and area deprivation across different ethnic groups in the UK. Results of the multilevel regression models show that, after adjusting for area deprivation, increased levels of social cohesion are found in areas of greater ethnic residential heterogeneity. Although different patterns emerge across ethnic groups and the measure of social cohesion used, findings consistently show that it is area deprivation, and not ethnic residential heterogeneity, which erodes social cohesion in the UK.

Interactions among human immunodeficiency virus (HIV)-1, interferon-gamma and receptor of activated NF-kappa B ligand (RANKL): implications for HIV pathogenesis

We reported recently that exposure of human T cells to soluble HIV-1 envelope glycoprotein gp120 induced biologically active tumour necrosis factor (TNF)-alpha-related cytokine receptor of activated NF-kappaB ligand (RANKL), the primary drive to osteoclast differentiation and bone resorption. Furthermore, certain anti-HIV protease inhibitors linked clinically to accelerated bone loss in HIV disease blocked the physiological control of RANKL activity by interferon (IFN)-gamma through inhibition of degradation of the RANKL nuclear adapter signalling protein, TNF receptor associated protein 6 (TRAF6). We now report a series of reciprocal interactions among HIV-1, RANKL and IFN-gamma. RANKL augmented HIV replication in acutely and chronically infected cells of T lymphocyte and monocyte lineage, effects which occurred at a transcriptional level in conjunction with activation of NF-kappaB. TNF-alpha and RANKL were markedly synergistic in induction of HIV. Low pharmacological levels of IFN-gamma (0.75-3 ng/ml) suppressed RANKL-driven enhancement of HIV replication, as did L-T6DP-1, a cell-permeable peptide inhibitor of TRAF6. In contrast, HIV replication induced by TNF-alpha and phorbol ester were not inhibited, and in some cases augmented, by IFN-gamma. We conclude that a positive feedback loop exists between RANKL production and HIV replication, which may be relevant to both the pathophysiology of HIV-linked osteopenia and control of HIV growth. This pathway appears distinct from those of other cytokine activators of HIV, with respect to its utilization of TRAF6 and its suppression by IFN-gamma. These data raise the possibility that TRAF-specific inhibitory peptides, alone or in conjunction with IFN-gamma, could be used to regulate HIV activation in vivo.

HIV-1 Vpr enhances production of receptor of activated NF-kappaB ligand (RANKL) via potentiation of glucocorticoid receptor activity

The HIV-1 accessory protein Vpr potentiates glucocorticoid (GC)-induced inhibition of a variety of immunologically important cytokines. We report the first instance of synergy between Vpr and GC in induction of a T cell cytokine, one which may underlie a metabolic complication of HIV infection. Accelerated bone resorption is an important complication of HIV disease and its treatment. Receptor of activated NF-kappaB ligand (RANKL) is the final effector of osteoclast differentiation and bone resorption. It is induced by exogenous GC, a prominent cofactor in bone mineral loss, as well as by elevated levels of endogenous GC, found in many patients with HIV disease. We document Vpr-mediated upregulation of RANKL, the dependence of this effect on GC receptor integrity, its function through a classic GC receptor motif, and its independence from Vpr-mediated G(2) cell cycle arrest. These data suggest a positive regulatory role for Vpr in transcriptional control of a cytokine that may be critical to one metabolic complication of HIV.

On being a Kunkel acolyte

Everything is interesting if you look at it deeply enough. There is no trivial question. This sentiment, attributed to Nobel laureate and physicist Richard Feynman, was Professor Henry Kunkel's message to all who began work in his laboratory. Learn as much as you can from a single informative patient. Keep looking. Play. But play, of course, in the Kunkel sense of exploration. The life of a Kunkel acolyte might be characterized as rejection, endurance and very late dinners. But then, on a few occasions, there was the thrill of a discovery he'd always help guide.

Endothelial cell apoptotic genes associated with the pathogenesis of thrombotic microangiopathies: an application of oligonucleotide genechip technology

Idiopathic thrombotic thrombocytopenic purpura (TTP) is a disease characterized by the apoptotic injury of all microvascular endothelial cells (MVEC) except those of pulmonary origin. It notably also spares EC of large vessel origin. It is fatal unless treated with plasma exchange. The EC lineage restriction of the apoptotic lesions in vivo is reproduced in vitro following exposure of primary human MVEC derived from various tissues to TTP plasma. Oligonucleotide genechip technology was used to identify genes that may contribute to the resistance of lung MVEC to apoptosis induced by TTP plasma and to explore the intrinsic genotypic heterogeneity between MVEC of TTP-sensitive (skin) versus resistant (lung) lineage. Exposure of cells to TTP or normal plasma yielded 157 genes that were differentially expressed in primary human lung MVEC. A global change in expression of pro- and anti-apoptotic genes was seen, including increases in caspase 1, Fas, and Bcl-xl, already shown by experimental means to be involved in TTP pathogenesis. Additional differences suggest the importance of pathways related to the death receptor ligand TRAIL, as well as a role for disruption of EC-extracellular matrix interactions in the initiation of apoptosis. Maintenance of specific prosurvival signals at baseline may be a feature of lung MVEC resistance in TTP as suggested by higher expression than skin EC of the TRAIL antagonist, osteoprotegerin, and the vascular endothelial growth factors, VEGF/VPF and VEGF-C, and their receptors, VEGFR-2 (KDR) and VEGFR-3 (Flt4).

'Reverse gear' cellular movement mediated by chemokines

We sought to model the mechanism by which leucocytes may be actively repulsed by a beta-chemokine signal. This model is used to interpret an apparent paradox in chemokine biology, whereby high levels of a T-cell chemoattractant, stromal cell derived factor-1 (SDF-1), are present in bone marrow and thymic tissues despite a paucity of mature T lymphocytes in these areas. We postulate the differential involvement in cell migration of the two binding sites on SDF-1 for its sole receptor, CXCR4, depending on whether high or low concentrations of SDF-1 are encountered by the cell. Site choice would be mediated by divergent affinities of the two binding interactions. We also propose differential signalling following SDF-1/CXCR4 interactions on the plasma membrane versus ligand/receptor complexes in endocytic vesicles. Preliminary data showing divergent susceptibility to kinase inhibitors depending on whether a cell is attracted to or repulsed by SDF-1, are consistent with this model. In terms of physical movement toward or away from a chemokine gradient, we compare the cycling of surface receptors during migration to the caterpillar drive of a tractor, which can change direction simply by altering the direction of rotation of its threads. Finally, the potential clinical implications of concentration-dependent, chemokine-based cell attraction and repulsion are discussed.

Plasma timolol concentrations of timolol maleate: timolol gel-forming solution (TIMOPTIC-XE) once daily versus timolol maleate ophthalmic solution twice daily

PURPOSE

The objective of this study was to compare plasma concentrations of timolol following multiple dosing of the therapeutic regimens of timolol maleate ophthalmic gel-forming solution (Timolol GS; TIMOPTIC-XE) and timolol maleate ophthalmic solution. Timolol maleate ophthalmic gel-forming solution is also referred to as Timolol GS, i.e. gel-forming solution.

METHODS

This was a masked observer, two-period crossover study in six normal male subjects randomized to receive either Timolol GS, 0.5% (TIMOPTIC-XE,) once daily (0530 hours) or timolol maleate ophthalmic solution (0.5% TIMOPTIC) twice daily (0530 and 1730 hours) for 8 days, in both eyes. On Day 8, a blood sample was obtained prior to treatment, as well as 1, 2, 4, 8, 10, 12, 13, 14, 16, and 24 hours following the morning instillation. After a 7-day inter-period washout interval, subjects received the opposite treatment.

RESULTS

Timolol GS (TIMOPTIC-XE): Plasma concentrations of timolol rarely exceeded 0.375 ng/ml (the lower limit of assay quantification). For all subjects, peak plasma concentrations of timolol averaged <0.3 ng/ml within 4 hours after the last dose. The highest single observation was 0.49 ng/ml in one subject (at hour 2). Timolol solution: For all subjects, peak plasma concentrations of timolol averaged about 0.5 ng/ml and 0.3 ng/ml within 4 hours following the first and second dose, respectively, on Day 8. The highest single observation was 0.95 ng/ml in one subject (at hour 2).

CONCLUSIONS

The data suggest that there is less systemic exposure to timolol following once-daily therapy with Timolol GS 0.5% compared with twice daily therapy with timolol maleate ophthalmic solution 0.5%.

Adhering to antiretroviral therapies

In 1999, the AIDS program conducted a survey of more than 1,000 patients in Sao Paulo [Brazil]. It found that 69 percent achieved 80 percent adherence, which means they took their medicine properly 80 percent of the time. According to Margaret Chesney, a professor of medicine at the University of California at San Francisco who studies behavioral factors in AIDS treatment, this rate is not sufficient to control the virus - which can kill even people who take their medicine faithfully - but it is no different from adherence rates in the United States. A study in San Diego showed that 72 percent of patients took their medicine 80 percent of the time.

Efficacy and tolerability of timolol maleate ophthalmic gel-forming solution versus timolol ophthalmic solution in adults with open-angle glaucoma or ocular hypertension: a six-month, double-masked, multicenter study

BACKGROUND

Timolol has been formulated in a highly purified gellan gum to improve its duration of action. The efficacy of this formulation in short-term studies using once-daily dosing has been reported.

OBJECTIVE

The purpose of this study was to evaluate the efficacy and tolerability of 0.5% timolol maleate ophthalmic gel-forming solution (timolol GS) given once daily versus 0.5% timolol solution given twice daily in a long-term trial.

METHODS

This was a multicenter, double-masked, 6-month trial. After a washout of ocular hypotensive medication, 286 patients with open-angle glaucoma or ocular hypertension were randomly assigned in a 2:1 ratio to receive 0.5% timolol GS in both eyes once daily or 0.5% timolol solution in both eyes twice daily. All patients received a morning (9 AM) and evening (9 PM) dose. For patients in the timolol GS group, the evening dose consisted of a vehicle only, whereas for patients in the timolol solution group, both doses consisted of active drug. Intraocular pressure (IOP) was measured at trough (before morning instillation) and peak (2 hours after instillation) at follow-up examinations at weeks 2, 4, 8, 12, and 24. Adverse events were monitored using patient reports.

RESULTS

Of the 286 patients randomized, 191 received timolol GS and 95 received timolol solution. Ninety-three percent of patients (265/286) completed the study. At the end of the treatment interval (week 24), the mean decrease in IOP at trough ranged from 5.6 to 5.9 mm Hg in the timolol GS group and from 6.3 to 6.6 mm Hg in the timolol solution group. Similar efficacy was observed at 11 AM (peak). At week 24, the difference in mean IOP between treatments was -0.61 mm Hg (95% CI -1.44 to 0.22) at trough and -0.79 mm Hg (95% CI -1.77 to 0.20) at peak, indicating no significant difference between the 2 timolol formulations. The number of reports of blurred vision and tearing was significantly higher in the timolol GS group than in the timolol solution group (P = 0.04), whereas burning/stinging was reported more frequently in the timolol solution group than in the timolol GS group (P = 0.04). At week 12, the decrease in mean heart rate at trough (hour 0) was significantly less for patients in the timolol GS group than for those in the timolol solution group (-1.1 vs -4.2 bpm; P = 0.024). At week 24 (hour 0), the decrease in mean heart rate was less for patients treated with timolol GS by 2.5 bpm (P = 0.051). The heart rate data at peak (hour 2) was similar to that observed at trough at week 12 (-2.7 vs -5.7 bpm; P = 0.006) and week 24 (-3.1 vs -4.7 bpm; P = 0.063). The mean change in blood pressure was not significantly different between treatments. There were no clinically significant differences between the groups in visual acuity, biomicroscopy and ophthalmoscopy results, or visual fields.

CONCLUSIONS

Timolol 0.5% GS administered once daily was shown to be as effective in lowering IOP as the equivalent concentration of timolol 0.5% solution administered twice daily in patients with ocular hypertension or open-angle glaucoma.

Role of transforming growth factor beta1 in microvascular endothelial cell apoptosis associated with thrombotic thrombocytopenic purpura and hemolytic-uremic syndrome

Primary human microvascular endothelial cells (MVEC) of restricted lineage undergo apoptosis when exposed to plasma from patients with thrombotic thrombocytopenic purpura (TTP) and sporadic hemolytic-uremic syndrome (HUS). This reflects the pathology and tissue distribution of lesions in vivo. As extracellular matrix (ECM) is critical to MVEC survival, and cytokines which regulate ECM, such as transforming growth factor (TGF)-beta1, have been reported anecdotally to be altered in TTP/HUS, we examined the role of TGF-beta1 and two ECM proteins, fibronectin and thrombospondin (TSP), in these disorders. Levels of active TGF-beta1 were elevated in acute but not convalescent phases of TTP/sporadic HUS, as well as TTP associated with human immunodeficiency virus infection and use of the anti-platelet drug ticlopidine. MVEC from tissues susceptible to TTP-mediated apoptosis showed little active TGF-beta1 production when exposed to TTP plasmas. In contrast, pulmonary MVEC and large-vessel EC, which are resistant to TTP-linked pathology, showed marked induction of TGF-beta1 following TTP plasma exposure. Exogenous TGF-beta1 suppressed TTP plasma-mediated apoptosis in susceptible MVEC in association with blockade of cell entry into S phase. Soluble TSP, devoid of detectable bound TGF-beta1, had a similar effect, which paralleled its ability to induce TGF-beta1 production in MVEC. In vivo, TSP deposition was diminished markedly in involved tissues of TTP patients. These data highlight the role of TGF-beta1 and ECM in TTP and suggest that differential production of TGF-beta1 by MVEC may play a role in their sensitivity or resistance to TTP/sporadic HUS-mediated apoptosis in vitro and in vivo.

Legal considerations in group practices and physician management

Physicians are restructuring their practices in response to competition, managed care, and federal and state laws and regulations restricting their practice of medicine. Many physicians have formed group practices with the hope of selling this practice in the future. For physicians to profit from ancillary services, the group practice must meet federal and state requirements. If physicians choose to sell the group practice to a physician practice management company, careful review and negotiation of the purchase agreements are necessary to prevent complications if the arrangement is unsuccessful.