Development and Utility of a PAK1-Selective Degrader

Overexpression of PAK1, a druggable kinase, is common in several malignancies, and inhibition of PAK1 by small molecules has been shown to impede the growth and survival of such cells. Potent inhibitors of PAKs 1-3 have been described, but clinical development has been hindered by recent findings that PAK2 function is required for normal cardiovascular function in adult mice. A unique allosteric PAK1-selective inhibitor, NVS-PAK1-1, provides a potential path forward, but has modest potency. Here, we report the development of BJG-05-039, a PAK1-selective degrader consisting of NVS-PAK1-1 conjugated to lenalidomide, a recruiter of the E3 ubiquitin ligase substrate adaptor Cereblon. BJG-05-039 induced selective degradation of PAK1 and displayed enhanced anti-proliferative effects relative to its parent compound in PAK1-dependent, but not PAK2-dependent, cell lines. Our findings suggest that selective PAK1 degradation may confer more potent pharmacological effects compared with catalytic inhibition and highlight the potential advantages of PAK1-targeted degradation.

The use of continuous electronic prescribing data to infer trends in antimicrobial consumption and estimate the impact of stewardship interventions in hospitalized children

Background

Understanding antimicrobial consumption is essential to mitigate the development of antimicrobial resistance, yet robust data in children are sparse and methodologically limited. Electronic prescribing systems provide an important opportunity to analyse and report antimicrobial consumption in detail.

Objectives

We investigated the value of electronic prescribing data from a tertiary children’s hospital to report temporal trends in antimicrobial consumption in hospitalized children and compare commonly used metrics of antimicrobial consumption.

Methods

Daily measures of antimicrobial consumption [days of therapy (DOT) and DDDs] were derived from the electronic prescribing system between 2010 and 2018. Autoregressive moving-average models were used to infer trends and the estimates were compared with simulated point prevalence surveys (PPSs).

Results

More than 1.3 million antimicrobial administrations were analysed. There was significant daily and seasonal variation in overall consumption, which reduced annually by 1.77% (95% CI 0.50% to 3.02%). Relative consumption of meropenem decreased by 6.6% annually (95% CI −3.5% to 15.8%) following the expansion of the hospital antimicrobial stewardship programme. DOT and DDDs exhibited similar trends for most antimicrobials, though inconsistencies were observed where changes to dosage guidelines altered consumption calculation by DDDs, but not DOT. PPS simulations resulted in estimates of change over time, which converged on the model estimates, but with much less precision.

Conclusions

Electronic prescribing systems offer significant opportunities to better understand and report antimicrobial consumption in children. This approach to modelling administration data overcomes the limitations of using interval data and dispensary data. It provides substantially more detailed inferences on prescribing patterns and the potential impact of stewardship interventions.

Proteus mirabilis - a rare cause of non-HACEK Gram-negative infective endocarditis

Infective endocarditis caused by Proteus mirabilis is strikingly rare. Here, we describe the case of an 86-year old man with five recurrent septic episodes over a period of three months associated with Proteus mirabilis bacteraemia secondary to underlying Proteus endocarditis. The final diagnosis was made based on clinical findings, blood culture results and transoesophageal echocardiogram. The patient was treated medically with 6 weeks of ceftriaxone and long-term oral ciprofloxacin. On completion of intravenous therapy the patient remained well. We performed a literature review and found this to be only the fourth confirmed case of Proteus mirabilis endocarditis successfully treated with antibiotic therapy alone. This case highlights an important but rare cause of endocarditis, reinforcing the need to consider this diagnosis in recurrent Gram-negative bacteraemia even if by an atypical organism.

Two-year analysis of Clostridium difficile ribotypes associated with increased severity

Background

Certain Clostridium difficile ribotypes have been associated with complex disease phenotypes including recurrence and increased severity, especially the well-described hypervirulent RT027. This study aimed to determine the pattern of ribotypes causing infection and the association, if any, with severity.

Methods

All faecal samples submitted to a large diagnostic laboratory for C. difficile testing between 2011 and 2013 were subject to routine testing and culture. All C. difficile isolates were ribotyped, and associated clinical and demographic patient data were retrieved and linked to ribotyping data.

Results

In total, 86 distinct ribotypes were identified from 705 isolates of C. difficile. RT002 and RT015 were the most prevalent (22.5%, N=159). Only five isolates (0.7%) were hypervirulent RT027. Ninety of 450 (20%) patients with clinical information available died within 30 days of C. difficile isolation. RT220, one of the 10 most common ribotypes, was associated with elevated median C-reactive protein and significantly increased 30-day all-cause mortality compared with RT002 and RT015, and with all other ribotypes found in the study.

Conclusions

A wide range of C. difficile ribotypes were responsible for C. difficile infection presentations. Although C. difficile-associated mortality has reduced in recent years, expansion of lineages associated with increased severity could herald increases in future mortality. Enhanced surveillance for emerging lineages such as RT220 that are associated with more severe disease is required, with genomic approaches to dissect pathogenicity.

Using Social Media to Reduce Multiple Risk Factors for CRC in Rural Appalachians: #CRCFREE

Purpose: To examine the efficacy, acceptability, feasibility, and applicability of a Facebook (FB) intervention designed to reduce multiple colorectal cancer (CRC) risk factors in older adults residing in rural Appalachian Kentucky. Methods: We piloted a 12 week FB intervention culturally tailored for older adults residing in rural Eastern Kentucky to impact CRC risk factors, including: nutrition, physical activity, and screening. Participants were aged 50+, had internet access, and were at risk for CRC. During the 12 week study, the participants received three daily posts via secret FB group regarding CRC risk factors. Demographics, dietary measures, body mass index (BMI), and CRC screening were assessed at baseline and post intervention. FB engagement and physical activity were tracked throughout the intervention. Dietary measures included the Healthy Eating Index (HEI) and Dietary Inflammatory Index (DII). Physical activity was tracked using Fitbits. Post-intervention focus group interviews were conducted to assess feasibility and acceptability. Results: Participants (n = 57) were Caucasian, aged 58 ± 6 years, predominately female (67%), and the majority reported at least a high school education (77%). Post intervention, participants experienced significant increase in HEI scores (49.94 ± 9.84 vs. 58.60 ± 12.06, P = < 0.01). DII scores significantly decreased (2.44 ±1.12 vs. 1.60 ± 1.63, P = 0.003). There was no significant change in physical activity, BMI, or screening status. Participants, on average, viewed more than half of the posts. Focus group participants found FB posts to be useful and motivating. They reported that FB posts were educational and motivational. Conclusion: This pilot study shows promising preliminary data to support using a FB intervention in rural Appalachian older adults to decrease CRC risks. Participants were receptive to FB intervention, and FB provides a unique and accessible method for health promotion in hard to reach populations.

Abstract LB-303: Substrate-mimetic covalent inhibitor of MALT1 is most effective against CARD11 mutant ABC-DLBCL

Diffuse Large B-cell lymphoma is the most common subtype of B-cell non Hodgkin Lymphoma (B-NHL) representing 30% of all B-NHL. There are three molecular subtypes: germinal center B cell-like (GCB) DLBCL, activated B cell-like (ABC) DLBCL, and primary mediastinal B cell lymphoma (PMBL). Of those, Activated B-cell like Diffuse Large B-cell Lymphoma (ABC-DLBCL) represents a third of the patients and is characterized by constitutive NF-κB activity due to mutations in various proteins of the B-cell receptor (BCR) as well as Toll-like receptor (TLR) pathways. Mutations in the BCR pathway include: activating mutations of CD79A/B (20% of ABC-DLBCLs) and CARD11 (10%) and deletion or inactivating mutation of A20 (20-30%). In the TLR pathway, MYD88 is mutated in 37% of ABC-DLBCL patients. Given this scenario, numerous therapeutic strategies targeting proteins signaling downstream of the BCR pathway have been proposed for ABC-DLBCL -including inhibitors targeting kinases SYK, BTK, PI3K, PKC, MAPKs and AKT or the protease MALT1. MALT1 inhibition provides advantages to other targets because it is downstream of most of the BCR pathway mutations present in patients, including CARD11. Patients with CARD11 mutations do not respond to BTK inhibitors. However, none of the MALT1 inhibitors reported to date are good candidates for clinical use.

Here we report a new class of substrate mimetic MALT1 inhibitors based on Z-VRPR-fmk. Our lead compound, SCM-02-138 displayed nanomolar potency in biochemical and cellular MALT1 protease reporter assays. Crystallography shows covalent binding of the compound to MALT1 active site Cys residue. SCM-02-138 was highly selective for MALT1 and showed over 100-fold differential killing in sensitive vs resistant cell lines. MALT1 inhibition was most effective in CARD11 mutant cells. SCM-02-138 was active in vivo, as assessed by hIL10 inhibition in xenografted models of ABC-DLBCL cell lines. Moreover it was effective against ABC-DLBCL xenografts and PDX DLBCL ex vivo. Combination of SCM-02-138 with other BCR inhibitors revealed PI3K delta inhibition as the most synergistic combination. Combination of SCM-02-138 and CAL-101 potentiated both proliferation inhibition and apoptosis.

In summary, we have developed a new class of MALT1 peptidic inhibitor characterized by nanomolar potency, irreversibility and high specificity. This inhibitor will be particularly useful against CARD11 mutant ABC-DLBCL, which are resistant to BTK inhibitors.

Citation Format: Lorena Fontan, David Scott, John Hatcher, Qi Qiao, Ilkay Us, Gabriella Casalena, Mariette Bekkers, Ulrike Philippar, Matthew Durant, Spandan Chennamadhavuni, Hao Wu, Nathaniel Gray, Ari Melnick. Substrate-mimetic covalent inhibitor of MALT1 is most effective against CARD11 mutant ABC-DLBCL [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-303. doi:10.1158/1538-7445.AM2017-LB-303

Total meniscectomy in adolescents: a 40-year follow-up

We continued a prospective longitudinal follow-up study of 53 remaining patients who underwent open total meniscectomy as adolescents and who at that time had no other intra-articular pathology of the knee. Their clinical, radiological and patient-reported outcomes are described at a mean follow-up of 40 years (33 to 50). The cohort of patients who had undergone radiological evaluation previously after 30 years were invited for clinical examination, radiological evaluation and review using two patient-reported outcome measures. A total of seven patients (13.2%) had already undergone total knee replacement at the time of follow-up. A significant difference was observed between the operated and non-operated knee in terms of range of movement and osteoarthritis of the tibiofemoral joint, indicating a greater than fourfold relative risk of osteoarthritis at 40 years post-operatively. All patients were symptomatic as defined by the Knee Injury and Osteoarthritis Outcome Score. This study represents the longest follow-up to date and it can be concluded that meniscectomy leads to symptomatic osteoarthritis of the knee later in life, with a resultant 132-fold increase in the rate of total knee replacement in comparison to their geographical and age-matched peers.

Cancer survival in Australia, Canada, Denmark, Norway, Sweden, and the UK, 1995-2007 (the International Cancer Benchmarking Partnership): an analysis of population-based cancer registry data

BACKGROUND

Cancer survival is a key measure of the effectiveness of health-care systems. Persistent regional and international differences in survival represent many avoidable deaths. Differences in survival have prompted or guided cancer control strategies. This is the first study in a programme to investigate international survival disparities, with the aim of informing health policy to raise standards and reduce inequalities in survival.

METHODS

Data from population-based cancer registries in 12 jurisdictions in six countries were provided for 2·4 million adults diagnosed with primary colorectal, lung, breast (women), or ovarian cancer during 1995-2007, with follow-up to Dec 31, 2007. Data quality control and analyses were done centrally with a common protocol, overseen by external experts. We estimated 1-year and 5-year relative survival, constructing 252 complete life tables to control for background mortality by age, sex, and calendar year. We report age-specific and age-standardised relative survival at 1 and 5 years, and 5-year survival conditional on survival to the first anniversary of diagnosis. We also examined incidence and mortality trends during 1985-2005.

FINDINGS

Relative survival improved during 1995-2007 for all four cancers in all jurisdictions. Survival was persistently higher in Australia, Canada, and Sweden, intermediate in Norway, and lower in Denmark, England, Northern Ireland, and Wales, particularly in the first year after diagnosis and for patients aged 65 years and older. International differences narrowed at all ages for breast cancer, from about 9% to 5% at 1 year and from about 14% to 8% at 5 years, but less or not at all for the other cancers. For colorectal cancer, the international range narrowed only for patients aged 65 years and older, by 2-6% at 1 year and by 2-3% at 5 years.

INTERPRETATION

Up-to-date survival trends show increases but persistent differences between countries. Trends in cancer incidence and mortality are broadly consistent with these trends in survival. Data quality and changes in classification are not likely explanations. The patterns are consistent with later diagnosis or differences in treatment, particularly in Denmark and the UK, and in patients aged 65 years and older.

FUNDING

Department of Health, England; and Cancer Research UK.

Administration of misoprostol by trained traditional birth attendants to prevent postpartum haemorrhage in homebirths in Pakistan: a randomised placebo-controlled trial

Objective

To determine if misoprostol is safe and efficacious in preventing postpartum haemorrhage (PPH) when administered by trained traditional birth attendants (TBA) at home deliveries.

Design

A randomised, double-blind, placebo-controlled trial.

Setting

Chitral, Khyber Pakhtunkhwa Province, Pakistan.

Population

A total of 1119 women giving birth at home.

Methods

From June 2006 to June 2008, consenting women were randomised to receive 600 μg oral misoprostol (n = 534) or placebo (n = 585) after delivery to determine whether misoprostol reduced the incidence of PPH (≥500 ml).

Main outcome measures

The primary outcomes were measured blood loss ≥500 ml after delivery and drop in haemoglobin >2 g/dl from before to after delivery.

Results

Oral misoprostol was associated with a significant reduction in the rate of PPH (≥500 ml) (16.5 versus 21.9%; relative risk 0.76, 95% CI 0.59–0.97). There were no measurable differences between study groups for drop in haemoglobin >2 g/dl (relative risk 0.79, 95% CI 0.62–1.02); but significantly fewer women receiving misoprostol had a drop in haemoglobin >3 g/dl, compared with placebo (5.1 versus 9.6%; relative risk 0.53, 95% CI 0.34–0.83). Shivering and chills were significantly more common with misoprostol. There were no maternal deaths among participants.

Conclusions

Postpartum administration of 600 μg oral misoprostol by trained TBAs at home deliveries reduces the rate of PPH by 24%. Given its ease of use and low cost, misoprostol could reduce the burden of PPH in community settings where universal oxytocin prophylaxis is not feasible. Continual training and skill-building for TBAs, along with monitoring and evaluation of programme effectiveness, should accompany any widespread introduction of this drug.

Trial registration

http://clinicaltrials.gov/NCT00120237 Misoprostol for the Prevention of Postpartum Hemorrhage in Rural Pakistan.

Development of a stress scale for pregnant women in the South Asian context: the A-Z Stress Scale

Stress in pregnancy can lead to low-birth-weight and preterm babies and to psychological consequences such as anxiety and depression during pregnancy and the puerperium. Previous scales to measure stress contain items that overlap with the symptoms of pregnancy. A stress scale was developed based on in-depth interviews with pregnant women in Pakistan. Construct validity, test-retest reliability and inter-rater reliability were carried out. Cronbach alpha was 0.82 for the 30 short-listed items, with item-total correlations of 0.2-0.8. Multidimensional scaling determined 2 dimensions: socioenvironmental hassles and chronic illnesses. This was the first scale developed for pregnant women based on stressors in a developing country in South Asia.

Effect of low vs. high dietary sodium on blood pressure levels in a normotensive Indo-Asian population

BACKGROUND

Hypertension is a major modifiable risk factor, and while sodium restriction in hypertensive patients appears effective, its role in normotensive individuals remains unclear. We assessed the effect of a low vs. high-sodium diet on blood pressure in normotensive Indo-Asian adults.

METHODS

A randomized, controlled, crossover trial was conducted on 200 normotensive subjects randomly selected from the general population in Karachi, Pakistan. Participants were randomized to either a low (20 mEq/day) or a high-sodium diet (220 mEq/day) for 1 week, followed by 1 week of washout, then the alternate diet for 1 week. The primary outcome was difference in systolic blood pressure (SBP) measured at the end of each phase in the overall population.

RESULTS

Mean (95% confidence interval) decline in 24-h urinary sodium excretion was 81.0 (69.6-92.4) mEq/day (P < 0.001), and in SBP was 1 (0-3)mm Hg (P = 0.17) between high and low-sodium phase. A significant interaction was detected (P = 0.001) between dietary sodium and baseline SBP with a greater adjusted mean (95% confidence interval) decline in SBP (6 (2-9)mm Hg) among participants with high-normal SBP (130-139 mm Hg) and no significant change (-1(-2 to 1)) in those with normal baseline SBP (<130 mm Hg), respectively.

CONCLUSIONS

Reducing sodium intake has a beneficial effect on blood pressure in Indo-Asians with high-normal SBP, at least in the short term. Given the ubiquity of high-normal blood pressure (BP), and frank hypertension in this population, we argue that primary prevention strategies, targeted at use of discretionary sodium, should now be designed and evaluated.

Rise in childhood obesity with persistently high rates of undernutrition among urban school-aged Indo-Asian children

BACKGROUND

Childhood obesity is an emerging global public health challenge. Evidence for the transition in nutrition in Indo-Asian developing countries is lacking. We conducted these analyses to determine the trends in nutritional status of school-aged children in urban Pakistan.

METHODS

Data on the nutritional status of children aged 5 to 14 years from two independent population-based representative surveys, the urban component of the National Health Survey of Pakistan (NHSP; 1990-1994) and the Karachi survey (2004-2005), were analysed. Using normative data from children in the United States as the reference, trends for age- and gender-standardised prevalence (95% CI) of underweight (more than 2 SD below the weight-for-age reference), stunted (more than 2 SD below the height-for-age reference) and overweight and obese (body mass index (BMI) 85(th) percentile or greater) children were compared for the two surveys. The association between physical activity and being overweight or obese was analysed in the Karachi survey using logistical regression analysis.

RESULTS

2074 children were included in the urban NHSP and 1675 in the Karachi survey. The prevalence of underweight children was 29.7% versus 27.3% (p = 0.12), stunting was 16.7% versus 14.3% (p = 0.05), and prevalence of overweight and obese children was 3.0 versus 5.7 (p<0.001) in the NHSP and Karachi surveys, respectively. Physical activity was inversely correlated with being overweight or obese (odds ratio, 95% CI, 0.51, 0.32-0.80 for those who engaged in more than 30 minutes of physical activity versus those engaged in less than 30 minutes' activity).

CONCLUSIONS

Our study highlights the challenge faced by Pakistani school-aged children. There has been a rapid rise in the number of overweight and obese children despite a persistently high burden of undernutrition. Focus on prevention of obesity in children must include strategies for promoting physical activity.

Maternal risk factors associated with low birth weight in Karachi: a case-control study

To evaluate maternal risk factors associated with low birth weight (LBW) among women aged 15-35 years, we carried out a hospital-based, case-control study on 262 cases (mothers of neonates weighing < or = 2.5 kg) and 262 controls (mothers of neonates weighing > 2.5 kg). Odds of delivering a low-birth-weight baby decreased with increase in maternal haemoglobin [odds ratio (OR): 0.701; 95% confidence interval (CI): 0.62-0.79]. Odds were greater among mothers not using iron supplements during pregnancy (OR: 2.88; 95% CI: 1.83-4.54). Mothers of LBW babies had lower haemoglobin levels before delivery.

Chlorproguanil-dapsone versus sulfadoxine-pyrimethamine for sequential episodes of uncomplicated falciparum malaria in Kenya and Malawi: a randomised clinical trial

BACKGROUND

Chlorproguanil-dapsone exerts lower resistance pressure on Plasmodium falciparum than does sulfadoxine-pyrimethamine, but is rapidly eliminated. We aimed to find out whether chlorproguanil-dapsone results in a higher retreatment rate for malaria than sulfadoxine-pyrimethamine.

METHODS

In a randomised trial of paediatric outpatients with uncomplicated falciparum malaria, patients received either chlorproguanil-dapsone or sulfadoxine-pyrimethamine and were followed up for up to 1 year. Sites were in Kenya (n=410) and Malawi (n=500). We used per-protocol analysis to assess the primary outcome of annual malaria incidence.

FINDINGS

Drop-outs were 117 of 410 (28.5%) in Kenya, and 342 of 500 (68.4%) in Malawi. Follow-up was for a median of 338 days (IQR 128-360) and 342 days (152-359) in Kilifi (chlorproguanil-dapsone and sulfadoxine-pyrimethamine, respectively), and for 120 days (33-281) and 84 days (26-224) in Blantyre. Mean annual malaria incidence was 2.5 versus 2.1 in Kenya (relative risk 1.16, 95% CI 0.98-1.37), and 2.2 versus 2.8 in Malawi (0.77, 0.63-0.94). 4.3% versus 12.8%, and 5.4% versus 20.1%, of patients were withdrawn for treatment failure in Kenya and Malawi, respectively. In Kenya haemoglobin concentration of 50 g/L or less caused exit in 6.9% of chlorproguanil-dapsone patients and 1.5% of sulfadoxine-pyrimethamine patients, but most anaemia occurred before re-treatment. In Malawi only one patient exited because of anaemia.

INTERPRETATION

Despite the rapid elimination of chlorproguanil-dapsone, children treated with this drug did not have a higher incidence of malaria episodes than those treated with sulfadoxine-pyrimethamine. Treatment failure was more common with sulfadoxine-pyrimethamine. Cause of anaemia in Kenya was probably not adverse reaction to chlorproguanil-dapsone, but this observation requires further study.

Emigration patterns of cancer cases in Alberta, Canada

Cancer registries are a unique source of data for population-based analysis of survival of cancer cases, but information on current vital status is essential. This paper describes a method to determine the last known vital status of cases and the emigration pattern of cancer cases diagnosed in Alberta. Data from the Alberta Cancer Registry (ACR) for the years 1985 1993 (83,446 cases), were linked to the Alberta Health Care Insurance Plan (AHCIP) registration file to identify cases that had left the province, and the date they emigrated. Ninety-nine percent of the ACR cases linked correctly to the AHCIP registration file. Three percent of cases had left Alberta by March 1998; For the first five years of follow-up between 0.6% and 0.8% of cases alive at the beginning of each year of follow-up left the province in the succeeding year. Seven percent of those diagnosed under 45 years of age left the province compared to less than 2% of those aged 65 and over. There was no difference in emigration patterns between the sexes. The cancer sites with good prognosis tended to have the highest proportion of emigrants.

A beta peptide vaccination prevents memory loss in an animal model of Alzheimer's disease

Vaccinations with amyloid-beta peptide (A beta) can dramatically reduce amyloid deposition in a transgenic mouse model of Alzheimer's disease. To determine if the vaccinations had deleterious or beneficial functional consequences, we tested eight months of A beta vaccination in a different transgenic model for Alzheimer's disease in which mice develop learning deficits as amyloid accumulates. Here we show that vaccination with A beta protects transgenic mice from the learning and age-related memory deficits that normally occur in this mouse model for Alzheimer's disease. During testing for potential deleterious effects of the vaccine, all mice performed superbly on the radial-arm water-maze test of working memory. Later, at an age when untreated transgenic mice show memory deficits, the A beta-vaccinated transgenic mice showed cognitive performance superior to that of the control transgenic mice and, ultimately, performed as well as nontransgenic mice. The A beta-vaccinated mice also had a partial reduction in amyloid burden at the end of the study. This therapeutic approach may thus prevent and, possibly, treat Alzheimer's dementia.

Mice overexpressing human uncoupling protein-3 in skeletal muscle are hyperphagic and lean

Uncoupling protein-3 (UCP-3) is a recently identified member of the mitochondrial transporter superfamily that is expressed predominantly in skeletal muscle. However, its close relative UCP-1 is expressed exclusively in brown adipose tissue, a tissue whose main function is fat combustion and thermogenesis. Studies on the expression of UCP-3 in animals and humans in different physiological situations support a role for UCP-3 in energy balance and lipid metabolism. However, direct evidence for these roles is lacking. Here we describe the creation of transgenic mice that overexpress human UCP-3 in skeletal muscle. These mice are hyperphagic but weigh less than their wild-type littermates. Magnetic resonance imaging shows a striking reduction in adipose tissue mass. The mice also exhibit lower fasting plasma glucose and insulin levels and an increased glucose clearance rate. This provides evidence that skeletal muscle UCP-3 has the potential to influence metabolic rate and glucose homeostasis in the whole animal.

Glial glutamate transporter GLT-1 down-regulation precedes delayed neuronal death in gerbil hippocampus following transient global cerebral ischemia

Glial (GLT-1 and GLAST) and neuronal (EAAC1) high-affinity transporters mediate the sodium dependent glutamate reuptake in mammalian brain. Their dysfunction leads to neuronal damage by allowing glutamate to remain in the synaptic cleft for a longer duration. The purpose of the present study is to understand their contribution to the ischemic delayed neuronal death seen in gerbil hippocampus following transient global cerebral ischemia. The protein levels of these three transporters were studied by immunoblotting as a function of reperfusion time (6 h to 7 days) following a 10 min occlusion of bilateral common carotid arteries in gerbils. In the vulnerable hippocampus, there was a significant decrease in the protein levels of GLT-1 (by 36-46%, P < 0.05; between 1 and 3 days of reperfusion) and EAAC1 (by 42-68%, P < 0.05; between 1 and 7 days of reperfusion). Histopathological evaluation showed no neuronal loss up to 2 days of reperfusion but an extensive neuronal loss (by approximately 84%, P < 0.01) at 7 days of reperfusion in the hippocampal CA1 region. The time frame of GLT-1 dysfunction (1-3 days of reperfusion) precedes the initiation of delayed neuronal death (2-3 days of reperfusion). This suggests GLT-1 dysfunction as a contributing factor for the hippocampal neuronal death following transient global cerebral ischemia. Furthermore, decreased EAAC1 levels may contribute to GABAergic dysfunction and excitatory/inhibitory imbalance following transient global ischemia.

Functional assessments in mice and rats after focal stroke

This paper presents a comprehensive assessment of sensorimotor deficits in the mouse after focal ischaemia induced by occlusion of the middle cerebral artery. Twenty four hours after induction of middle cerebral artery occlusion, mice showed deficits in a range of sensory and motor tasks as assessed by the SHIRPA protocol. In addition they exhibited a decrease in rotarod performance and locomotor activity. Some behaviours, such as locomotor activity, were also impaired in sham operated animals compared to normal controls, although these impairments were not as marked as those exhibited by the ischaemic mice. This is the first comprehensive analysis of the short term effects of permanent focal ischaemia in mice. In a second series of experiments in the rat, rates of recovery over time were examined. Simple (neurological grades, rotarod) and complex (sticky label test) tasks were examined in rats after middle cerebral artery occlusion up to 7 days post-ischaemia. Ischaemic rats had a profound deficit in contralateral performance on the sticky label task with no evidence of recovery. A less marked deficit was also observed in ipsilateral performance of this task. These deficits were still present 7 days after ischaemia. Ischaemic rats also exhibited a deficit on rotarod performance but this had recovered 7 days post-ischaemia. Thus different sensorimotor tasks have different rates of recovery after focal cerebral ischaemia in the rat. Further characterisation of these tasks will enhance their utility meaningful preclinical means of assessing functional recovery of the administration of potential neuroprotective and regenerative therapies.

Contribution of polyamine oxidase to brain injury after trauma

OBJECT

The possible role of the polyamine interconversion pathway on edema formation, traumatic injury volume, and tissue polyamine levels after traumatic brain injury (TBI) was studied using an inhibitor of the interconversion pathway enzyme, polyamine oxidase.

METHODS

Experimental TBI was induced in Sprague-Dawley rats by using a controlled cortical impact device at a velocity of 3 m/second, resulting in a 2-mm deformation. Immediately after TBI was induced, 100 mg/kg of N1,N4-bis(2,3-butadienyl)-1,4-butanediamine 2HCl (MDL 72527) or saline was injected intraperitoneally. Brain water content and tissue polyamine levels were measured at 24 hours after TBI. Traumatic injury volume was evaluated using 2% cresyl violet solution 7 days after TBI occurred. The MDL 72527 treatment significantly reduced brain edema (80.4+/-0.8% compared with 81.2+/-1.2%, p < 0.05) and injury volume (30.1+/-6.6 mm3 compared with 42.7+/-13.3 mm3, p < 0.05) compared with the saline treatment. The TBI caused a significant increase in tissue putrescine levels at the traumatized site (65.5+/-26.5 nmol/g [corrected] in the cortex and 70.9+/-22.4 nmol/g [corrected] in the hippocampus) compared with the nontraumatized site (7+/-2.4 nmol/g [corrected] in the cortex and 11.4+/-6.4 nmol/g [corrected] in the hippocampus). The increase in putrescine levels in both the traumatized and nontraumatized cortex and hippocampus was reduced by a mean of 60% with MDL 72527 treatment.

CONCLUSIONS

These results demonstrate, for the first time, that the polyamine interconversion pathway has an important role in the increase of putrescine levels after TBI and that the polyamine oxidase inhibitors, blockers of the interconversion pathway, can be neuroprotective against edema formation and necrotic cavitation after TBI.

Therapeutic substitution and therapeutic conservatism as cost-containment strategies in primary care: a study of fundholders and non-fundholders

BACKGROUND

General practice (GP) fundholders contained prescribing costs by restricting the rise in volume of prescribing and by increasing generic prescribing. It is uncertain whether they used more sophisticated approaches to medicine choice in attempts to contain costs.

AIM

To examine whether fundholding practices have adopted medicine-specific strategies to contain prescribing costs--i.e. switching to less expensive but equally effective medicines or resisting the uptake of newer more expensive medicines--by examination of the prescribing of ulcer-healing and antidepressant medicines in the period before and after practices became fundholders.

METHOD

Comparison of prescribing data of 52 fundholding practices before fundholding and after fundholding with that of matched non-fundholding practices. Measures examined were prescribing costs (net ingredient cost in each therapeutic area per ASTRO-pu); prescribing volume (defined daily doses per ASTRO-pu); the proportion of all ulcer-healing medicines prescribed as cimetidine, ranitidine, nizatidine, and as proton pump inhibitors; and the proportion of all antidepressant medicines prescribed as selective serotonin re-uptake inhibitors.

RESULTS

In comparison with non-fundholding practices, fundholders increasingly prescribed less expensive medicines (cimetidine and nizatidine) within the class of histamine2 receptor antagonists. However, fundholders adopted proton pump inhibitors or selective serotonin re-uptake inhibitors at the same rate as non-fundholders.

CONCLUSION

Fundholders have used therapeutic substitution with medicines of equal effectiveness to contain prescribing costs. There is no evidence that fundholders have been slower than non-fundholders to use newer, more expensive medicines.

Effects of MDL 72527, a specific inhibitor of polyamine oxidase, on brain edema, ischemic injury volume, and tissue polyamine levels in rats after temporary middle cerebral artery occlusion

The possible effects of the polyamine interconversion pathway on tissue polyamine levels, brain edema formation, and ischemic injury volume were studied by using a selective irreversible inhibitor, MDL 72527, of the interconversion pathway enzyme, polyamine oxidase. In an intraluminal suture occlusion model of middle cerebral artery in spontaneously hypertensive rats, 100 mg/kg MDL 72527 changed the brain edema formation from 85.7 +/- 0.3 to 84.5 +/- 0.9% in cortex (p < 0.05) and from 79.9 +/- 1.7 to 78.4 +/- 2.0% in subcortex (difference not significant). Ischemic injury volume was reduced by 22% in the cortex (p < 0.05) and 17% in the subcortex (p < 0.05) after inhibition of polyamine oxidase by MDL 72527. There was an increase in tissue putrescine levels together with a decrease in spermine and spermidine levels at the ischemic site compared with the nonischemic site after ischemia-reperfusion injury. The increase in putrescine levels at the ischemic cortical and subcortical region was reduced by a mean of 45% with MDL 72527 treatment. These results suggest that the polyamine interconversion pathway has an important role in the postischemic increase in putrescine levels and that blocking of this pathway can be neuroprotective against neuronal cell damage after temporary focal cerebral ischemia.

The association of some practice characteristics with antibiotic prescribing

BACKGROUND

Antibiotic prescribing in general practice is often considered inappropriate, and its volume excessive. Considerable variation in antibiotic prescribing volume and costs exists among practices.

OBJECTIVE

To investigate some factors behind the variation in antibiotic prescribing among general practices, by examining the contribution to this variation of the level of deprivation in the practice population, training status, partnership status, and fundholding status.

METHOD

Analysis of prescribing data (PACT) from 351 practices in the Mersey region for the year ending March 1991 and the year ending March 1994; prescribing data standardized for variation in practice population demography. Use of multiple linear regressions to investigate the variation among practices in standardized prescribing volume and standardized prescribing costs, in both years.

RESULTS

Level of deprivation, training status and partnership status contributed to the models explaining variation in prescribing volume. The same variables contributed to the model explaining variation in prescribing costs in the year ending March 1991. For the year ending March 1994, level of deprivation, training status, and fundholding status contributed to all models.

CONCLUSION

Higher levels of antibiotic prescribing occur in practices serving more deprived communities, in single-handed practices, and in non-training practices. These higher levels of prescribing may be due to higher levels of morbidity, but may also reflect the organization and attitudes of these practices.

The influence of practice characteristics on the prescribing of benzodiazepines and appetite suppressant drugs

BACKGROUND

The prescribing volume of benzodiazepines and of appetite suppressant drugs have been suggested as possible indicators of prescribing quality.

OBJECTIVE

To investigate the variation among general practices in the prescribing of benzodiazepines and appetite suppressants by examining the contribution to this variation of training status, partnership status, fundholding status and the level of deprivation in the practice population.

METHODS

Prescribing data (PACT) were analysed for 350 practices in the former Mersey Regional Health Authority, for the year ending March 1991 and the year ending March 1994. Data were first standardized for variation in practice population demography. Multiple linear regressions were used to investigate the variation among practices in standardized prescribing volume in both years.

RESULTS

For benzodiazepines, training status and partnership status contributed to all models and level of deprivation contributed to some (percentage of variation explained for year ending March 1991: 10% to 21%, year ending March 1994: 8% to 20%). For appetite suppressant drugs fundholding status and an interaction between training status and level of deprivation contributed to all models in both years (percentage of variation explained for year ending March 1991: 19% to 20%, year ending March 1994: 20% to 21%).

CONCLUSION

The prescribing of benzodiazepines is lower in training practices, in multi-partner practices and in practices serving a less deprived population, while the prescribing of appetite suppressant drugs is lower in training practices and in fundholding practices. Variation in prescribing knowledge, organizational and management capabilities and patient demand may be explanatory factors.

The selective 5-HT1B receptor inverse agonist 1'-methyl-5-[[2'-methyl-4'-(5-methyl-1,2, 4-oxadiazol-3-yl)biphenyl-4-yl]carbonyl]-2,3,6,7-tetrahydro- spiro[furo[2,3-f]indole-3,4'-piperidine] (SB-224289) potently blocks terminal 5-HT autoreceptor function both in vitro and in vivo

5-HT1 receptors are members of the G-protein-coupled receptor superfamily and are negatively linked to adenylyl cyclase activity. The human 5-HT1B and 5-HT1D receptors (previously known as 5-HT1Dbeta and 5-HT1Dalpha, respectively), although encoded by two distinct genes, are structurally very similar. Pharmacologically, these two receptors have been differentiated using nonselective chemical tools such as ketanserin and ritanserin, but the absence of truly selective agents has meant that the precise function of the 5-HT1B and 5-HT1D receptors has not been defined. In this paper we describe how, using computational chemistry models as a guide, the nonselective 5-HT1B/5-HT1D receptor antagonist 4 was structurally modified to produce the selective 5-HT1B receptor inverse agonist 5, 1'-methyl-5-[[2'-methyl-4'-(5-methyl-1,2, 4-oxadiazol-3-yl)biphenyl-4-yl]carbonyl]-2,3,6, 7-tetrahydrospiro[furo[2,3-f]indole-3,4'-piperidine] (SB-224289). This compound is a potent antagonist of terminal 5-HT autoreceptor function both in vitro and in vivo.

Chlorproguanil-dapsone: effective treatment for uncomplicated falciparum malaria

Pyrimethamine-sulfadoxine, the first choice for uncomplicated falciparum malaria in Africa, exerts strong selection pressure for resistance because of its slow elimination. It is likely that resistance will emerge rapidly, and there is no widely affordable replacement. Chlorproguanil-dapsone is cheap, rapidly eliminated, more potent than pyrimethamine-sulfadoxine, and could be introduced in the near future to delay the onset of antifolate resistance and as "salvage therapy" for pyrimethamine-sulfadoxine failure. A total of 448 children were randomly allocated (double blind) to either a single dose of pyrimethamine-sulfadoxine or to one of two chlorproguanil-dapsone regimens: a single dose or three doses at 24-h intervals. Reinfections are clinically indistinguishable from recrudescence and are more likely after treatment with rapidly eliminated drugs; we measured the incidence of parasitemia in 205 initially aparasitemic children to allow comparison with the three treatment groups. The patients and a community surveillance group were followed up for 28 days. At the study end point, 31.2% (95% confidence interval, 24.9-38.0) of the community surveillance group subjects were parasitemic, compared with subjects in the treatment groups, whose rates of parasitemia were 40.8% (32.9-49.0; relative risk [RR], 1.31 [0.99-1.73]) after triple-dose chlorproguanil-dapsone, 19.7% (13.5-27.2; RR, 0.63 [0.43-0.93]) after pyrimethamine-sulfadoxine, and 65.6% (57.5-73.0; RR, 2.10 [1.66-2.65]) after single-dose chlorproguanil-dapsone. Pyrimethamine-sulfadoxine and triple-dose chlorproguanil-dapsone were effective treatments. Pyrimethamine-sulfadoxine provided chemoprophylaxis during follow-up because of its slow elimination. Triple-dose chlorproguanil-dapsone should now be developed in an attempt to reduce the rate of emergence of antifolate resistance in Africa and for affordable salvage therapy in cases of pyrimethamine-sulfadoxine failure.

General practice fundholders' prescribing savings in one region of the United Kingdom, 1991-1994

Since 1991, fundholding general practitioners in the UK have had a financial incentive to contain prescribing costs. Research has confirmed that fundholding practices have contained their prescribing costs more effectively than non-fundholding practices, but how much fundholders have actually saved by changing their prescribing is difficult to quantify. Fundholders are allocated a prescribing budget, and the underspend on this budget has been taken to represent savings produced by changing prescribing behaviour. However, this assumes accuracy of budget setting, which has been questioned. The objective of this study was to estimate the true savings in prescribing made by fundholders during the first 3 years of fundholding, without making assumptions about the accuracy of budget setting. We compare this to underspends on prescribing budgets. The results suggest that budget setting did not give fundholders over-generous budgets and that budget underspends are justified by the true savings in prescribing.

Nutrition knowledge and obesity of adults in community residences

Variation in nutrition knowledge of adults with mild or moderate mental retardation (30 obese, 27 nonobese) from four community agencies was examined as a function of their body mass and level of mental retardation. They completed a nutrition knowledge test adapted for individuals with mental retardation. Multiple regression analyses revealed significant effects of level of mental retardation and body mass on nutrition knowledge. Adults with mild mental retardation possessed greater nutrition knowledge than did those with moderate mental retardation, and obese individuals possessed more knowledge than did nonobese individuals. The unexpected relation between nutrition knowledge and degree of obesity implies an influential role for environmental factors in the development of obesity.

Randomised controlled trial of treatment of chronic suppurative otitis media in Kenyan schoolchildren

BACKGROUND

The outcomes of treatment of chronic suppurative otitis media (CSOM) are disappointing and uncertain, especially in developing countries. Because CSOM is the commonest cause of hearing impairment in children in these countries, an effective method of management that can be implemented on a wide scale is needed. We report a randomised, controlled trial of treatment of CSOM among children in Kenya; unaffected schoolchildren were taught to administer the interventions.

METHODS

We enrolled 524 children with CSOM, aged 5-15 years, from 145 primary schools in Kiambu district of Kenya. The schools were randomly assigned treatments in clusters of five in a ratio of two to dry mopping alone (201 children), two to dry mopping with topical and systemic antibiotics and topical steroids (221 children), and one to no specific treatment (102 children). Schools were matched on factors thought to be related to their socioeconomic status. The primary outcome measures were resolution of otorrhoea and healing of tympanic membranes on otoscopy by 8, 12, and 16 weeks after induction. Absence of perforation was confirmed by tympanometry, and hearing levels were assessed by audiometry. 29 children were withdrawn from the trial because they took non-trial antibiotics. There was no evidence of differences in timing of withdrawals between the groups.

FINDINGS

By the 16-week follow-up visit, otorrhoea had resolved in a weighted mean proportion of 51% (95% CI 42-59) of children who received dry mopping with antibiotics, compared with 22% (14-31) of those who received dry mopping alone and 22% (9-35) of controls. Similar differences were recorded by the 8-week and 12-week visits. The weighted mean proportions of children with healing of the tympanic membranes by 16 weeks were 15% (10-21) in the dry-mopping plus antibiotics group, 13% (5-20) in the dry-mopping alone group, and 13% (3-23) in the control group. The proportion with resolution in the dry-mopping alone group did not differ significantly from that in the control group at any time. Hearing thresholds were significantly better for children with no otorrhoea at 16 weeks than for those who had otorrhoea, and were also significantly better for those whose ears had healed than for those with otorrhoea at all times.

INTERPRETATION

Our finding that dry mopping plus topical and systemic antibiotics is superior to dry mopping alone contrasts with that of the only previous community-based trial in a developing country, though it accords with findings of most other trials in developed countries. The potential role of antibiotics needs further investigation. Further, similar trials are needed to identify the most cost-effective and appropriate treatment regimen for CSOM in children in developing countries.

Influences of practice characteristics on prescribing in fundholding and non-fundholding general practices: an observational study

OBJECTIVE

To investigate the variation in prescribing among general practices by examining the contribution to this variation of fundholding, training status, partnership status, and the level of deprivation in the practice population and to investigate the extent to which fundholding has been responsible for any changes in prescribing.

DESIGN

Analysis of prescribing data (PACT) for the years 1990-1 (before fundholding) and 1993-4 (after fundholding), Use of multiple linear regressions to investigate the variation among practices in total prescribing costs (net ingredient cost per prescribing units), and mean cost per item in each of the two years and also the change in these variables between years.

SETTING

Former Mersey region.

SUBJECTS

384 practices.

RESULTS

The models developed explained the variation in cost per item (43% of variation explained for 1990-1, 38% for 1993-4) and prescribing volume (34% for 1990-1, 38% for 1993-4) better than the variation in total prescribing costs (3% for 1990-1, 7% for 1993-4). The models developed to explain the change in these variables between years did not explain more than 10% of the variation. Most of the explained variation in the change in total prescribing costs was accounted for by fundholding. Of the pounds 3.71 saved by first wave fundholders compared with non-fundholders pounds 3.57 was attributable to fundholding alone.

CONCLUSION

In neither year did fundholding make a major contribution to the variation in prescribing behaviour among practices, which was better explained by deprivation, training status, and partnership status, but it did seem largely responsible for differences in the rise of total prescribing costs between fundholders and non fundholders.

A prevalence study of ear problems in school children in Kiambu district, Kenya, May 1992

Information on the prevalence of hearing impairment and related ear pathologies in children in sub-Saharan Africa is scarce. A pilot study for a clinical trial of simple treatments for chronic suppurative otitis media (CSOM) in school children in Kiambu district, Kenya, provided information on the prevalence of hearing impairment and ear pathologies. Five-thousand-three-hundred-sixty-eight children from 57 randomly chosen primary schools in Kiambu district were examined. Simple otoscopy was performed by clinical officers with specialty training in ENT, and hering testing was performed by trained nurses, using a hand held field audiometer. Microbiological specimens were obtained from those children with CSOM. Five-point-six percent of the children had a hearing impairment of > 30 dB HL in one or both ears, with 2.2% having bilateral hearing impairment. Two-point-four percent had at least one perforated tympanic membrane, and 1.1% had CSOM. Eight-point-six percent of the children had wax obstructing the tympanic membrane. There is evidence of a relationship between hearing impairment and both CSOM and wax obstructing the tympanic membrane. The most common organisms found were Pseudomonas spp. (34%), Proteus spp. (34%) and Eschericia coli (19%). These results are comparable with other studies in Africa and indicate a considerable burden of ear disease in Kiambu district, Kenya.

The 1993 General Social Survey I: alcohol use in Canada

Rates and correlates of alcohol use are reported from the 1993 General Social Survey, a household telephone survey of 10,385 Canadians carried out by Statistics Canada. Continuing a recent trend, alcohol use has declined. The portrait of the Canadian who is most likely to drink and drink heavily is that of a young adult male who is not married, relatively well-off, and rarely or never attends religious services. In a multivariate analysis of the combined impact of sociodemographic factors on drinking and drinking levels, it was found that the frequency of religious attendance and age were the strongest predictors of current drinking. Gender was the strongest predictor of volume of alcohol consumption, while religious attendance, age, marital status and employment status were also significant predictors.

The 1993 General Social Survey II: alcohol problems in Canada

Rates and correlates of problems associated with the use of alcohol are reported from the 1993 General Social Survey in Canada. Approximately 1 in 11 drinkers (9.2%) reported that drinking has had an adverse effect on his or her social life, physical health, happiness, home life or marriage, work, or finances in the past year. The most commonly reported problems concerned physical health (5.1%), and financial position (4.7%). Approximately one in eight drinkers (12.9%) had driven a car within an hour after consuming two or more drinks in the previous year. Furthermore, more than two of every five respondents reported that they had experienced some problem due to other people's drinking. In a multivariate analysis, age, marital status, gender, religious attendance and employment status were the strongest predictors of problem drinking. The number of heavy drinking occasions is a stronger predictor of drinking problems than is overall level of consumption.

Reliability of the Health Utilities Index--Mark III used in the 1991 cycle 6 Canadian General Social Survey Health Questionnaire

This study presents information on the test-retest reliability of the Health Utility Index--Mark III (HUI) system used in cycle 6 of the Canadian General Social Survey (GSS). The HUI system used in this reliability study consists of an eight-attribute health status classification system (HSCS) and a function for generating a summary score of health-related quality of life. To estimate test-retest reliability, a stratified random sample of individuals (n = 506) completing GSS telephone interviews during August and September, 1991 were interviewed again 1 month later. Weighting adjustments based on the probability of selection were invoked during the analyses to provide unbiased estimates of test-retest reliability for all GSS respondents in the August-September period. The results indicate that the individual questions, attributes and provisional index scores generally provided reliable information on health status in the GSS. The exceptions to this were limitations in speech and dexterity which were reported very infrequently. Kappa estimates of test-retest reliability for individual questions varied from 0.184 to 0.766. For the eight attributes, kappa estimates varied from 0.137 to 0.728. Using the provisional index scores to quantify health overall, a test-retest reliability of 0.767 was obtained (intra-class correlation coefficient).