Obesity-linked suppression of membrane-bound O-acyltransferase 7 (MBOAT7) drives non-alcoholic fatty liver disease

Recent studies have identified a genetic variant rs641738 near two genes encoding membrane bound O-acyltransferase domain-containing 7 (MBOAT7) and transmembrane channel-like 4 (TMC4) that associate with increased risk of non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), alcohol-related cirrhosis, and liver fibrosis in those infected with viral hepatitis (Buch et al., 2015; Mancina et al., 2016; Luukkonen et al., 2016; Thabet et al., 2016; Viitasalo et al., 2016; Krawczyk et al., 2017; Thabet et al., 2017). Based on hepatic expression quantitative trait loci analysis, it has been suggested that MBOAT7 loss of function promotes liver disease progression (Buch et al., 2015; Mancina et al., 2016; Luukkonen et al., 2016; Thabet et al., 2016; Viitasalo et al., 2016; Krawczyk et al., 2017; Thabet et al., 2017), but this has never been formally tested. Here we show that Mboat7 loss, but not Tmc4, in mice is sufficient to promote the progression of NAFLD in the setting of high fat diet. Mboat7 loss of function is associated with accumulation of its substrate lysophosphatidylinositol (LPI) lipids, and direct administration of LPI promotes hepatic inflammatory and fibrotic transcriptional changes in an Mboat7-dependent manner. These studies reveal a novel role for MBOAT7-driven acylation of LPI lipids in suppressing the progression of NAFLD.

Non-alcoholic fatty liver disease, or NAFLD for short, is a medical condition that develops when the liver accumulates excess fat. It can lead to complications such as diabetes and liver scarring. In humans, mutations that inactivate a protein called MBOAT7 increase the risk of fat accumulating in the liver.

Genetic studies suggest that low levels of MBOAT7 in a human’s liver cells increase the severity of NAFLD. Yet the links between MBOAT7, NAFLD and obesity are not well understood. Helsley et al. used data from humans and from obese mice that had been fed a high-fat diet to investigate the relationship between NAFLD and MBOAT7. This revealed that people who are obese have lower levels of MBOAT7 in their livers. Next, obese mice were genetically manipulated to produce less MBOAT7, which led them to develop more severe NAFLD.

Helsley et al. then grew human liver cells in the laboratory and lowered their levels of MBOAT7, which led to excess fat accumulating in the cells. This increase in fat accumulation was, at least in part, due to how these cells metabolize fats when MBOAT7 is reduced: they start making more new fats and consume fewer lipids to produce energy.

These findings provide a link between obesity and liver damage in both humans and mice, and show how a decrease in MBOAT7 levels causes changes in fat metabolism that could lead to NAFLD. The results could drive new approaches to treating liver damage in patients with mutations in the gene that codes for MBOAT7.

Effect of Roux-en-Y gastric bypass on liver mitochondrial dynamics in a rat model of obesity

Bariatric surgery provides significant and durable improvements in glycemic control and hepatic steatosis, but the underlying mechanisms that drive improvements in these metabolic parameters remain to be fully elucidated. Recently, alterations in mitochondrial morphology have shown a direct link to nutrient adaptations in obesity. Here, we evaluate the effects of Roux-en-Y gastric bypass (RYGB) surgery on markers of liver mitochondrial dynamics in a diet-induced obesity Sprague-Dawley (SD) rat model. Livers were harvested from adult male SD rats 90-days after either Sham or RYGB surgery and continuous high-fat feeding. We assessed expression of mitochondrial proteins involved in fusion, fission, mitochondrial autophagy (mitophagy) and biogenesis, as well as differences in citrate synthase activity and markers of oxidative stress. Gene expression for mitochondrial fusion genes, mitofusin 1 (Mfn1; P < 0.05), mitofusin 2 (Mfn2; P < 0.01), and optic atrophy 1 (OPA1; P < 0.05) increased following RYGB surgery. Biogenesis regulators, peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α; P < 0.01) and nuclear respiratory factor 1 (Nrf1; P < 0.05), also increased in the RYGB group, as well as mitophagy marker, BCL-2 interacting protein 3 (Bnip3; P < 0.01). Protein expression for Mfn1 (P < 0.001), PGC1α (P < 0.05), BNIP3 (P < 0.0001), and mitochondrial complexes I-V (P < 0.01) was also increased by RYGB, and Mfn1 expression negatively correlated with body weight, insulin resistance, and fasting plasma insulin. In the RYGB group, citrate synthase activity was increased (P < 0.02) and reactive oxygen species (ROS) was decreased compared to the Sham control group (P < 0.05), although total antioxidant capacity was unchanged between groups. These data are the first to show an association between RYGB surgery and improved markers of liver mitochondrial dynamics. These observed improvements may be related to weight loss and reduced energetic demand on the liver, which could facilitate normalization of glucose homeostasis and protect against hepatic steatosis.

The essential role of exercise in the management of type 2 diabetes

Exercise is typically one of the first management strategies advised for patients newly diagnosed with type 2 diabetes. Together with diet and behavior modification, exercise is an essential component of all diabetes and obesity prevention and lifestyle intervention programs. Exercise training, whether aerobic or resistance training or a combination, facilitates improved glucose regulation. High-intensity interval training is also effective and has the added benefit of being very time-efficient. While the efficacy, scalability, and affordability of exercise for the prevention and management of type 2 diabetes are well established, sustainability of exercise recommendations for patients remains elusive.

EPRS is a critical mTORC1-S6K1 effector that influences adiposity in mice

Metabolic pathways that contribute to adiposity and ageing are activated by the mammalian target of rapamycin complex 1 (mTORC1) and p70 ribosomal protein S6 kinase 1 (S6K1) axis. However, known mTORC1-S6K1 targets do not account for observed loss-of-function phenotypes, suggesting that there are additional downstream effectors of this pathway. Here we identify glutamyl-prolyl-tRNA synthetase (EPRS) as an mTORC1-S6K1 target that contributes to adiposity and ageing. Phosphorylation of EPRS at Ser999 by mTORC1-S6K1 induces its release from the aminoacyl tRNA multisynthetase complex, which is required for execution of noncanonical functions of EPRS beyond protein synthesis. To investigate the physiological function of EPRS phosphorylation, we generated Eprs knock-in mice bearing phospho-deficient Ser999-to-Ala (S999A) and phospho-mimetic (S999D) mutations. Homozygous S999A mice exhibited low body weight, reduced adipose tissue mass, and increased lifespan, similar to S6K1-deficient mice and mice with adipocyte-specific deficiency of raptor, an mTORC1 constituent. Substitution of the Eprs^S999D allele in S6K1-deficient mice normalized body mass and adiposity, indicating that EPRS phosphorylation mediates S6K1-dependent metabolic responses. In adipocytes, insulin stimulated S6K1-dependent EPRS phosphorylation and release from the multisynthetase complex. Interaction screening revealed that phospho-EPRS binds SLC27A1 (that is, fatty acid transport protein 1, FATP1), inducing its translocation to the plasma membrane and long-chain fatty acid uptake. Thus, EPRS and FATP1 are terminal mTORC1-S6K1 axis effectors that are critical for metabolic phenotypes.

Regulation of Hepatic Triacylglycerol Metabolism by CGI-58 Does Not Require ATGL Co-activation

Adipose triglyceride lipase (ATGL) and comparative gene identification 58 (CGI-58) are critical regulators of triacylglycerol (TAG) turnover. CGI-58 is thought to regulate TAG mobilization by stimulating the enzymatic activity of ATGL. However, it is not known whether this coactivation function of CGI-58 occurs in vivo. Moreover, the phenotype of human CGI-58 mutations suggests ATGL-independent functions. Through direct comparison of mice with single or double deficiency of CGI-58 and ATGL, we show here that CGI-58 knockdown causes hepatic steatosis in both the presence and absence of ATGL. CGI-58 also regulates hepatic diacylglycerol (DAG) and inflammation in an ATGL-independent manner. Interestingly, ATGL deficiency, but not CGI-58 deficiency, results in suppression of the hepatic and adipose de novo lipogenic program. Collectively, these findings show that CGI-58 regulates hepatic neutral lipid storage and inflammation in the genetic absence of ATGL, demonstrating that mechanisms driving TAG lipolysis in hepatocytes differ significantly from those in adipocytes.

The TMAO-Generating Enzyme Flavin Monooxygenase 3 Is a Central Regulator of Cholesterol Balance

Circulating levels of the gut microbe-derived metabolite trimethylamine-N-oxide (TMAO) have recently been linked to cardiovascular disease (CVD) risk. Here, we performed transcriptional profiling in mouse models of altered reverse cholesterol transport (RCT) and serendipitously identified the TMAO-generating enzyme flavin monooxygenase 3 (FMO3) as a powerful modifier of cholesterol metabolism and RCT. Knockdown of FMO3 in cholesterol-fed mice alters biliary lipid secretion, blunts intestinal cholesterol absorption, and limits the production of hepatic oxysterols and cholesteryl esters. Furthermore, FMO3 knockdown stimulates basal and liver X receptor (LXR)-stimulated macrophage RCT, thereby improving cholesterol balance. Conversely, FMO3 knockdown exacerbates hepatic endoplasmic reticulum (ER) stress and inflammation in part by decreasing hepatic oxysterol levels and subsequent LXR activation. FMO3 is thus identified as a central integrator of hepatic cholesterol and triacylglycerol metabolism, inflammation, and ER stress. These studies suggest that the gut microbiota-driven TMA/FMO3/TMAO pathway is a key regulator of lipid metabolism and inflammation.

Deletion of CGI-58 or adipose triglyceride lipase differently affects macrophage function and atherosclerosis

Cellular TG stores are efficiently hydrolyzed by adipose TG lipase (ATGL). Its coactivator comparative gene identification-58 (CGI-58) strongly increases ATGL-mediated TG catabolism in cell culture experiments. To investigate the consequences of CGI-58 deficiency in murine macrophages, we generated mice with a targeted deletion of CGI-58 in myeloid cells (macCGI-58(-/-) mice). CGI-58(-/-) macrophages accumulate intracellular TG-rich lipid droplets and have decreased phagocytic capacity, comparable to ATGL(-/-) macrophages. In contrast to ATGL(-/-) macrophages, however, CGI-58(-/-) macrophages have intact mitochondria and show no indications of mitochondrial apoptosis and endoplasmic reticulum stress, suggesting that TG accumulation per se lacks a significant role in processes leading to mitochondrial dysfunction. Another notable difference is the fact that CGI-58(-/-) macrophages adopt an M1-like phenotype in vitro. Finally, we investigated atherosclerosis susceptibility in macCGI-58/ApoE-double KO (DKO) animals. In response to high-fat/high-cholesterol diet feeding, DKO animals showed comparable plaque formation as observed in ApoE(-/-) mice. In agreement, antisense oligonucleotide-mediated knockdown of CGI-58 in LDL receptor(-/-) mice did not alter atherosclerosis burden in the aortic root. These results suggest that macrophage function and atherosclerosis susceptibility differ fundamentally in these two animal models with disturbed TG catabolism, showing a more severe phenotype by ATGL deficiency.

Characteristics of persons with spinal cord injury as documented by use of an interactive data system

RATIONALE

Physicians need information about their rehabilitation practices that shows the types of patients being seen and the outcomes for their rehabilitation programs. In order to obtain more information on secondary medical complications and prevention programs, and to provide the information to the spinal cord injury (SCI) rehabilitation team, an interactive data management system was developed.

RESULTS

Initial findings for the first 99 patients with SCI were presented for staff review. Demographic information indicated that patients typically lived in private residences, had at least a high school education, and had annual incomes < $20,000. There were nearly equal numbers of paraplegic and tetraplegic patients; 63% of patients were more than 50 years of age and 69% were more than 10 years post-injury. Over 80% of the patients reported satisfactory health, were physically active, and had adequate transportation. Paraplegic and tetraplegic patients had similar profiles for secondary complications.

CONCLUSIONS

The SCI staff was surprised that greater than 35% of patients with SCI reported current problems with spasticity, pain, and pressure ulcers. The staff was interested in obtaining additional patient-perception information including the severity of each problem, how the problem interfered with daily activity, and the desire for additional care. The staff felt that patients were reporting problems more often to the interviewer than to their physician. There was unanimous support for the ongoing collection of patient-perception information.

Coronary artery and abdominal aortic calcification are associated with cardiovascular disease in type 2 diabetes

AIMS/HYPOTHESIS

The goals of this study were to determine whether coronary calcium is associated with the presence of clinical cardiovascular disease in individuals with type 2 diabetes and if the measurement of abdominal aortic calcium may have an independent or added benefit as a surrogate marker for clinical vascular disease.

METHODS

A cross-sectional study of subjects with type 2 diabetes enrolled in seven medical centres in the USA participating in a Veterans Affairs Cooperative Study of glycaemic control. Enrolled subjects included 309 veterans over 40 years of age with type 2 diabetes, with or without stable cardiovascular disease, who had inadequate glycaemic control (HbA(1)c>7.5%) on oral agents and/or insulin. The study assessed lifestyle behaviours, standard cardiovascular risk factors and coronary artery and abdominal aorta calcification by electron beam computed tomography.

RESULTS

Subjects with coronary artery or abdominal aorta calcification present had a strikingly higher prevalence of peripheral artery disease, coronary artery disease and all combined cardiovascular disease. Prevalence of each condition increased from 5- to 13-fold with increasing quintiles of coronary artery calcification and from 2- to 3-fold with increasing abdominal aorta calcification. These associations persisted after adjustment for lifestyle behaviours and standard cardiovascular risk factors.

CONCLUSIONS/INTERPRETATION

These results support the notion that vascular calcium in type 2 diabetes provides additional information beyond that of standard risk factors in identifying the presence of cardiovascular disease. Subclinical measures of atherosclerosis such as arterial calcification may help more precisely stratify these individuals and alert healthcare providers to those individuals who have particularly accelerated atherosclerosis.

Balancing benefit against risk in the choice of therapy for coronary artery disease. Lesson from prospective, randomized, clinical trials of percutaneous coronary intervention and coronary artery bypass graft surgery

The ageing world population faces a coming pandemic of high-risk coronary artery disease (CAD). Patients with CAD have 3 therapeutic options, which are based on objective clinical outcome: medical therapy and risk factor modification (Medicine), and 2 forms of revascularization, coronary artery bypass graft surgery (CABG), and percutaneous coronary intervention (PCI). More than 50 large (>100 patients), multicenter, prospective, randomized clinical trials (RCT) have compared these treatment options in terms of clinical benefits and patient risks. The randomized trials which demonstrated hard outcome (survival, myocardial infarction, stroke) benefits from statins, angiotensin-converting enzyme inhibition and thienopyridines have all been completed subsequent to the publication of most Medicine versus revascularization trials. These medical therapies, plus aspirin, beta-blockers, and risk factor modification, should be made available to patients regardless of the decision to revascularize, or the decision by what means (CABG or PCI). This review integrates the information from these trials, comparing the clinical benefits against the risks inherent in the 3 therapeutic options. The results of our review show that: trials of medicine versus revascularization (either CABG or PCI) support the revascularization paradox, in that the patients at highest risk of adverse outcome, from myocardial ischemia, have a hard outcome benefit (survival, MI, or stroke) from revascularization. This paradox, first seen in the Medicine versus CABG trials of the 1970s, is evident in the trials comparing fibrinolysis and other medicines, with primary PCI for ST-elevation myocardial infarction (MI). The paradox is evident in the conservative versus invasive strategy trials of non-ST-elevation MI and unstable angina, where the benefit of revascularization occurs only in high-risk subsets. The paradox often results in sicker patients, who have more to gain from revascularization, being denied it because of the elevated perception of risk (comparable to a reperfusion paradox in ST-elevation MI, where patients most likely to benefit from thrombolytics are denied them because of the perception of risk). Trials that compared medicine with revascularization for the treatment of acute MI support the use of PCI as the preferred early stabilization strategy (90% of all PAMI trial patients). The majority of the PCI versus CABG trials enrolled populations that were at relatively low risk for ischemic clinical events. These trials demonstrated few hard outcome (survival, MI, or stroke) differences between CABG and PCI. On the basis of the results obtained the following conclusions may be drawn: medicines are the primary options for stable, low-risk CAD, and should be given to all CAD patients. Medically refractory is a useful high-risk marker of potential benefit from revascularization. CABG continues to be the complete revascularization option for patients with multivessel, multi-lesion CAD, in part because of its application to chronic occlusions. PCI is the acute stabilization method of choice for patients with on-going ischemia and acute MI, especially among patients with hemodynamic compromise, and/or major comorbidity.

The construction and assessment of a statistical model for the prediction of protein assay data

The focus of this work is the development of a statistical model for a bioinformatics database whose distinctive structure makes model assessment an interesting and challenging problem. The key components of the statistical methodology, including a fast approximation to the singular value decomposition and the use of adaptive spline modeling and tree-based methods, are described, and preliminary results are presented. These results are shown to compare favorably to selected results achieved using comparitive methods. An attempt to determine the predictive ability of the model through the use of cross-validation experiments is discussed. In conclusion a synopsis of the results of these experiments and their implications for the analysis of bioinformatic databases in general is presented.

State level estimates of the incidence and economic burden of head injuries stemming from non-universal use of bicycle helmets

OBJECTIVE

To develop national and state level estimates for preventable bicycle related head injuries (BRHIs) and associated direct and indirect health costs from the failure to use bicycle helmets.

METHODS

Information on the effectiveness and prevalence of use of bicycle helmets was combined to estimate the avoidable fraction, that is, the proportion of BRHIs that could be prevented through the use of bicycle helmets. The avoidable fraction multiplied by the expected number of BRHIs gives an estimate of the number of preventable cases. Direct and indirect health costs are estimated from a social perspective for the number of preventable BRHIs to assess potential cost savings that would be achieved if all riders wore helmets.

RESULTS

Approximately 107,000 BRHIs could have been prevented in 1997 in the United States. These preventable injuries and deaths represent an estimated $81 million in direct and $2.3 billion in indirect health costs. Estimates range from 200 preventable BRHIs and $3 million in health costs in Wyoming (population 480,000) to 13,700 preventable BRHIs and $320 million in health costs in California (population 32.3 million).

CONCLUSIONS

A number of successful approaches to increasing bicycle helmet use exist, including mandatory use laws and community based programs. The limited use of these strategies may be related to the fact that too little information is available to state agencies about the public health and economic burden of these preventable injuries. In conjunction with information on program costs, our estimates can assist state planners in better quantifying the number of preventable BRHIs and the costs and benefits of helmet promotion programs.

Ethical issues at the start of life

In this article the fundamentals of a Jewish ethic are set out, through which today's pressing medical ethical questions are then broached. Ethics derive from a basic view of humanity. The Bible teaches that man is created in God's image, and every life is therefore sacrosanct. Second, since life is God-given we are its guarantors, not its owners. Finally, monotheism sees God as above nature and not in it, so nature itself is not holy--man can, and indeed should, try to improve upon it. With reference to specific medical issues, the need to be wary of the erosion of the family unit and of personal identity is stressed. Concerning abortion and stem cell research, the point is made that an embryo is not a person but is a potentiality and therefore not an object to be used. Regarding genetic intervention, a line is drawn between the therapeutic and the eugenic. Every technology carries with it the possibility of diminishing or enhancing human dignity. What matters is how we use it. The way to use it is in a covenant with God, honouring his image that is mankind.

Percutaneous coronary intervention versus coronary artery bypass graft surgery for patients with medically refractory myocardial ischemia and risk factors for adverse outcomes with bypass: a multicenter, randomized trial. Investigators of the Department of Veterans Affairs Cooperative Study #385, the Angina With Extremely Serious Operative Mortality Evaluation (AWESOME)

BACKGROUND

Percutaneous coronary intervention (PCI) and coronary artery bypass graft surgery (CABG) are being applied to high-risk populations, but previous randomized trials comparing revascularization methods have excluded a number of important high-risk groups.

OBJECTIVES

This five-year, multicenter, randomized clinical trial was designed to compare long-term survival among patients with medically refractory myocardial ischemia and a high risk of adverse outcomes assigned to either a CABG or a PCI strategy, which could include stents.

METHODS

Patients from 16 Veterans Affairs Medical Centers were screened to identify myocardial ischemia refractory to medical management and the presence of one or more risk factors for adverse outcome with CABG, including prior open-heart surgery, age >70 years, left ventricular ejection fraction <0.35, myocardial infarction within seven days or intraaortic balloon pump required. Clinically eligible patients (n = 2,431) underwent coronary angiography; 781 were angiographically acceptable; 454 (58% of eligible) patients consented to random assignment between CABG and PCI.

RESULTS

A total of 232 patients was randomized to CABG and 222 to PCI. The 30-day survivals for CABG and PCI were 95% and 97%, respectively. Survival rates for CABG and PCI were 90% versus 94% at six months and 79% versus 80% at 36 months (log-rank test, p = 0.46).

CONCLUSIONS

Percutaneous coronary intervention is an alternative to CABG for patients with medically refractory myocardial ischemia and a high risk of adverse outcomes with CABG.

Teaching a multidisciplinary approach to cancer treatment during surgical clerkship via an interactive board game

BACKGROUND

Although educators agree that the approach to cancer management must be multidisciplinary, medical students usually observe cancer patients through the eyes of a single specialist at any given time.

METHODS

In order to teach third-year medical students that cancer management is multidisciplinary, we developed the Oncology Game, an interactive, computer-assisted board game built on the principles of self-directed learning and student-student interaction. Eight "patients" with different histologic types of cancer are distributed randomly to 4 students, who play in teams of 2. The object is for the team to obtain the best treatment for its patients by advancing them via a roll of dice through surgical, medical, and radiation oncology clinics in the order most logical for the patient's particular cancer type. To test improvement in cognitive skills as a function of play, 16 students participated in a tournament taking parallel pretest and posttests before and after each round of play.

RESULTS

Students demonstrated a statistically significant change in the total number of questions answered correctly each time they played the Oncology Game (F = 4.16, P = 0.018; Pretest Round 1: 8.88 +/- 0.58; Posttest Round 1: 9.63 +/- 0.42; Pretest Round 2: 10.75 +/- 0.62; Posttest Round 2: 11.5 +/- 0.85). Post hoc pairwise comparison revealed a significant improvement in student performance after playing two rounds of the Oncology Game. Based on the postgame survey, students felt they improved their understanding of oncologic principles (4.56 +/- 0.13), knowledge of malignancies (4.50 +/- 0.13), and appreciation for the multidisciplinary nature of cancer management (4.56 +/- 0.13).

CONCLUSIONS

Improved test scores and postgame survey results demonstrate that third-year medical student students can learn about basic oncology principles and gain an appreciation for oncology as a multidisciplinary field of medicine through an interactive, computer-assisted board game.

Indications for a home standing program for individuals with spinal cord injury

Additional analyses were conducted on a recently published survey of persons with spinal cord injury (SCI) who used standing mobility devices. Frequency and duration of standing were examined in relation to outcomes using chi square analyses. Respondents (n = 99) who stood 30 minutes or more per day had significantly improved quality of life, fewer bed sores, fewer bladder infections, improved bowel regularity, and improved ability to straighten their legs compared with those who stood less time. Compliance with regular home standing (at least once per week) was high (74%). The data also suggest that individuals with SCI could benefit from standing even if they were to begin several years after injury. The observation of patient benefits and high compliance rates suggest that mobile standing devices should be more strongly considered as a major intervention for relief from secondary medical complications and improvement in overall quality of life of individuals with SCI.

A multicenter, randomized trial of percutaneous coronary intervention versus bypass surgery in high-risk unstable angina patients. The AWESOME (Veterans Affairs Cooperative Study #385, angina with extremely serious operative mortality evaluation) investigators from the Cooperative Studies Program of the Department of Veterans Affairs

This multicenter, prospective randomized trial was designed to test the hypotheses that percutaneous coronary intervention (PCI) is a safe and effective alternative to coronary artery bypass grafting (CABG) for patients with refractory ischemia and high risk of adverse outcomes. As a comparison of revascularization strategies, the trial specifically allows surgeons and interventionists to use new techniques as they become clinically available. After 42 months of this 72-month trial, 17,624 patients have been screened and 2022 met eligibility requirements: 341 have been randomized to either CABG or PCI, and the remaining 1681 are being prospectively followed in a registry. The 3-year overall survival of patients in the registry and randomized trial is comparable. To enhance accrual into the randomized trial, site visits were conducted, a few low-accruing hospitals were put on probation and/or replaced, eligibility criteria were reviewed at annual meetings of investigators, and the accrual period was extended by 1 year. These data demonstrate that a prospective randomized trial and registry of coronary revascularization for medically refractory high-risk patients is feasible.

Irrigation of soil with synthetic landfill leachate--speciation and distribution of selected pollutants

The fates and toxicities of selected landfill leachate pollutants in a soil with a low attenuation potential were investigated. Soil columns consisting of a loamy sand which had been irrigated with synthetic landfill leachates were dissected and analysed for pH, electrical conductivity, copper and zinc species, iron and phenol concentrations and microbial activity. Copper was found to be least mobile and accumulated in the top 4 cm of the soil columns. Sequential extraction of the soil revealed that at least two-thirds of the total copper was in the EDTA-, NaOH-extractable and residual fractions. Approximately 2% of the copper was water soluble and between 1 and 22% was in the MgCl(2)-extractable fraction. Zinc and phenol were relatively mobile and were detected throughout the soil-column profile as well as in the column effluents. The greatest zinc fraction (55-71%) was MgCl(2)-extractable. Zinc solubility in water was again low (1-4%). Phenol was partially adsorbed by the soil but its main attenuation occurred by biodegradation. Microbial activity was affected by the availability of the carbon source as well as the presence of copper and zinc. Copper was more inhibitory to microbial activity than zinc. In the presence of phenol, the simultaneous application of zinc and copper distinctly reduced microbial activity. No inhibitory effect of copper and zinc was observed in the absence of phenol when the microorganisms were severely carbon limited.

Firearm storage practices and children in the home, United States, 1994

OBJECTIVES

To estimate the national prevalence of firearm ownership and storage practices in the home, to compare storage practices in homes with and without children, and to analyze demographic characteristics related to firearm storage practices in homes with children.

DESIGN

A 1994 random-digit dialing telephone survey. We weighted the data to provide national estimates.

PARTICIPANTS

English- and Spanish-speaking adults in households in 50 states and Washington, DC.

MAIN OUTCOME MEASURES

Ownership of working powder firearm(s) in home and/or vehicle and firearm storage practices in the home.

RESULTS

Of 5238 households surveyed, one third kept at least 1 firearm in the home and/or vehicle. Of 1598 households with firearm(s) in the home and known firearm storage practices, 21.5% kept at least 1 gun loaded and unlocked in the home, 30.0% stored all firearms unloaded and locked, and 48.5% stored firearms in a manners classified between these 2 practices. Households with children were more likely than households without children to store all firearms unloaded and locked (41.5% vs 20.9%); households without children were more likely than households with children to store at least 1 firearm loaded and unlocked (29.8% vs 11.1%). Among households with children and firearms, there were regional differences with respect to storage practices.

CONCLUSIONS

These prevalence data show that children are potentially exposed to firearms in many households. This health threat illustrates the need for education about the issue of pediatric firearm injuries and for interventions to minimize associated risks. Health care providers should take advantage of opportunities to counsel patients regarding firearm safety in the home.

Analysis of protein activity data by Gaussian stochastic process models

The effects of certain chemical additives at maintaining a high level of activity in protein constructs during storage is investigated. We use a semiparametric regression technique to model the effects of the additives on protein activity. The model is extended to handle categorical explanatory variables. On the basis of the available data, the important factors are estimated to be buffer, detergent, protein concentration, and storage temperature. The relationships among protein activity and these factors appear to be moderately nonlinear with strong interaction effects. These features are revealed in a data-adaptive way by the semi parametric model, without explicit modeling of the nonlinearities or interactions. We use cross-validation to assess the fit of our model. The protein activity response appears to be extremely erratic. We recommend several sets of storage conditions and that further design points be chosen in regions around these estimated optima.

Urodynamic verification of noninvasive back-pressure recordings from the urinary bladder

Obstructive voiding is best evaluated with urodynamics, especially simultaneous measurement of bladder-pressure and urine flow rates. As an alternative to catheterization for urodynamics, noninvasive back-pressure methods using an external condom system have been introduced. This device uses one side tube in the condom for pressure recording and an outlet tube that is clamped for short periods of time during voiding. However, there have been problems with accurate back-pressure recording, including leaking, clamping techniques, hydrostatic pressures associated with pressure recording below the level of the symphysis pubis, and assessment of back pressures in relation to bladder and detrusor pressures. To address these issues, we have modified the condom for passing a catheter into the urethra for simultaneous direct bladder and back-pressure recording. The clamping device on the outlet tube also has been modified to produce back flushing of urine in addition to clamping. Hydrostatic issues have been addressed by making pressure recordings at the level of the symphysis pubis. Seven patients with obstructive symptoms were evaluated using these new devices. Back pressures were not statistically different than detrusor pressures recorded with a urethral catheter. Thus, the modifications have improved back-pressure recording techniques. The use of noninvasive back-pressure recording may be an important adjunct in the evaluation of obstructive uropathy.

Modified therapeutic community for homeless mentally ill chemical abusers. Sociodemographic and psychological profiles

This paper, the first in a series of reports from a field study on the efficacy of modified therapeutic community (TC) treatment for homeless mentally ill chemical abusers, presents sociodemographic profiles, psychiatric diagnosis, and psychological symptom data on 342 homeless mentally ill chemical abusing clients seeking treatment in mental health community residence settings. The findings reflect the multidimensional deficits, social dysfunctionality, and severity of psychopathology of the study sample. The paper discusses the implications of these findings for program design and program planning, with special reference to modified TC programs.

Modified therapeutic community for mentally ill chemical "abusers": background; influences; program description; preliminary findings

This paper briefly surveys the literature that addresses the problem of co-occurring mental and "substance abuse disorders." It discusses several convergent influences on the development of modified therapeutic community (TC) approaches. The paper describes in some detail the modified TC program for mentally ill chemical "abusers" (MICAs). The paper also summarizes research data that establish positive retention rates and significant in-treatment change to support the effectiveness of the modified TC and to underscore the limited effect of treatment-as-usual approaches. Treatment approaches must be comprehensive, multidimensional, of relatively long duration, and must systematically address the interrelated problems of mental illness and substance use.

Coronary angioplasty for elderly patients with "high risk" unstable angina: short-term outcomes and long-term survival

OBJECTIVES

We sought to compare the short- and long-term mortality rates in patients > or = 70 years old with unstable angina undergoing percutaneous transluminal coronary angioplasty (PTCA) with predicted coronary artery bypass graft surgery (CABG) short-term and U.S. census long-term mortality rates.

BACKGROUND

Coronary angioplasty is an alternative revascularization strategy for patients with medically refractory rest angina and a high risk of adverse outcomes with CABG. Patients > or = 70 years old are a specific high risk subset.

METHODS

A total of 131 consecutive patients aged > or = 70 years with unstable angina underwent PTCA; 82 (62%) of 131 had been refused CABG. Mortality over time was obtained from the Veterans Affairs Beneficiary Index Records Locator Subsystem. Predicted 30-day CABG-associated mortality was obtained from the Veterans Affairs Cardiac Risk Assessment Model. Mortality over time was expressed with Kaplan-Meier curves.

RESULTS

The observed 30-day angioplasty survival rate was 87% compared with the predicted surgical 30-day survival rate of 85.5%. In those patients who survived 6 months after angioplasty (84%), their subsequent 1-, 2-, 3-, 4- and 5-year survival rates were comparable to age-matched subjects in the U.S. census. Mortality in certain subsets known to be at very high risk for CABG-for example, patients who had a previous CABG-was not high in this cohort of elderly subjects. The extremely high risk subsets identified in this PTCA cohort (shock, heart failure, pressors required, balloon pump required) were relatively infrequent subsets.

CONCLUSIONS

For selected elderly patients with unstable angina deemed to be at "high risk" or even "prohibitive risk" for CABG, PTCA is an alternative revascularization strategy. The long-term mortality of successfully treated elderly patients is comparable to age-matched subjects. A prospective, multicenter, randomized trial of CABG versus PTCA, which includes patients > or = 70 years old, is being conducted (Veterans Affairs Cooperative Study 385: AWESOME).

Effect of outdoor airborne particulate matter on daily death counts

To investigate the possible relationship between airborne particulate matter and mortality, we developed regression models of daily mortality counts using meteorological covariates and measures of outdoor PM10. Our analyses included data from Cook County, Illinois, and Salt Lake County, Utah. We found no evidence that particulate matter < or = 10 microns (PM10) contributes to excess mortality in Salt Lake County, Utah. In Cook County, Illinois, we found evidence of a positive PM10 effect in spring and autumn, but not in winter and summer. We conclude that the reported effects of particulates on mortality are unconfirmed.

Effectiveness of percutaneous transluminal coronary angioplasty for patients with medically refractory rest angina pectoris and high risk of adverse outcomes with coronary artery bypass grafting

This study was undertaken to test the hypothesis that percutaneous transluminal coronary angioplasty (PTCA) is a reasonable alternative to coronary artery bypass grafting (CABG) for some high-risk patients with medically refractory rest angina. Over a 5-year period, 1 operator at a tertiary Veterans Affairs Medical Center performed angioplasty on 624 patients, of whom 441 had unstable angina. Of these 441 patients, 288 had rest angina and 225 had medically refractory rest angina. Medically refractory unstable angina was defined as reversible myocardial ischemia occurring at rest in an intensive care unit setting with low flow oxygen despite the following medications: (1) oral aspirin, intravenous heparin, or both; (2) some combination of beta blocker, calcium blocker, and/or nitrate so that resting heart rate is < 70 beats/min or resting blood pressure < 140 mm Hg, or both. There were 207 patients with medically refractory rest angina who had > or = 1 of the following characteristics predictive of a more than twofold increased risk of operative death at CABG: age > 70 years, prior CABG, recent myocardial infarct, need for intravenous nitroglycerin, need for intraaortic balloon pump, and left ventricular ejection fraction < 0.35. Of these 207 patients, 11 died (5%) during index hospitalization, 196 (95%) were discharged, and 186 (90%) went home angina free. There were 2 emergency CABGs and 9 acute myocardial infarctions. At follow-up (3 to 60 months, average 24), there were 27 late deaths (for a total of 38 [18%]), 8 (4%) late CABGs, and 44 (21%) late PTCAs (with 17 [8%] late myocardial infarctions). The 2-year mortality of 18% for this cohort is comparable to a 21% 2-year mortality observed in a group of 1,073 "high-risk" patients who underwent CABG in the Veterans Affairs Medical Center from 1987 to 1988. These data support the hypothesis that PTCA provides an alternative to CABG in some high-risk patients with medically refractory rest angina.

Evaluation of rotavirus infection and diarrhea in Iowa commercial pigs based on an epidemiologic study of a population represented by diagnostic laboratory cases

Group A, B, and C rotaviruses were identified in 9% (96/1,048) of pig fecal specimens submitted to the Iowa State University Veterinary Diagnostic Laboratory during 1987 and 1988. Six of the rotaviruses were group B, 5 were group C, and the remaining 89% were group A. Of the rotavirus cases with more than 1 serotype, 5 were multiple group A serotypes, 1 involved a group A and B serotype, and 1 included 2 group C serotypes. A retrospective epidemiologic evaluation of pig diarrhea in herds of origin was done using data obtained from the accession records of the rotavirus and 88 matched nonrotavirus pig diarrhea control cases. Herds from which rotavirus cases were derived experienced lower morbidity, mortality, and case fatality rates than matched control herds. The incidence of diarrhea decreased rapidly among all pigs from birth to 3 weeks of age. The peak incidence for piglet diarrhea occurred in February, and a moderate rise occurred in August-September. Definitive evidence for transmissible gastroenteritis virus was found in 12% of nonrotavirus cases but none of the rotavirus cases in which it was sought. Other pathogenic microorganisms were identified less frequently and inconsistently.

Percutaneous transluminal angioplasty of saphenous vein grafts for medically refractory unstable angina

OBJECTIVES

We attempted to answer the question, Is balloon angioplasty a reasonable alternative to repeat coronary artery bypass graft surgery in patients with previous coronary bypass graft surgery, medically refractory unstable angina and vein graft lesions?

BACKGROUND

Patients with medically refractory unstable angina need revascularization. Patients with previous coronary artery bypass graft surgery and medically refractory angina are at "high risk" for adverse outcomes with repeat coronary bypass graft surgery. Conversely, patients with angioplasty of old vein grafts are also at "high risk" for adverse outcomes.

METHODS

Balloon angioplasty of 89 lesions in saphenous vein grafts was performed in 75 consecutive patients with medically refractory unstable angina. Of these 75 patients, 24 (32%) had myocardial infarct within 30 days, 23 (31%) had left ventricular ejection fraction < 0.35, and 50 (67%) had major comorbidity. Patients underwent standard balloon angioplasty with aggressive use of intravenous and intracoronary heparin, urokinase, nitroglycerin, oral aspirin, calcium channel blocking agents and coumadin.

RESULTS

Angiographic success (reduction of stenosis < or = 50% without major complication) was seen in 84 of 89 lesions. Clinical success (angiographic success plus hospital discharge without major complication) was seen in 70 of 75 patients. During index hospitalization, two patients (3%) died, two (3%) had nonfatal infarcts, and one (1%) had emergency reoperation (coronary bypass graft surgery). In late follow up (3 to 66 months), 14 (20%) patients were lost to follow-up, 17 (23%) had repeat percutaneous transluminal coronary angioplasty, 2 (3%) had late bypass graft reoperation, 18 (25%) had late death, and 1 (< 1%) had a heart transplant. Of the 41 patients alive after one or more angioplasties, 25 have little or no angina, and 16 have occasional or more angina. We compared long-term survival rate in these 75 patients with a cohort of patients with high risk, unstable angina from the Veterans Affairs Surgical Registry (2,570 patients). The 30-day survival rate was better in patients with coronary angioplasty (97% vs. 92%, p < 0.05), but by 6 months there was no difference, and by 5 years a trend toward a higher survival rate with coronary artery bypass graft surgery was seen.

CONCLUSIONS

Balloon angioplasty of saphenous vein grafts with aggressive adjunctive pharmacotherapy is a reasonable alternative to repeat coronary bypass graft surgery in patients with medically refractory unstable angina, previous coronary bypass graft surgery and saphenous vein narrowing.

Negative emotion as predictor of relapse in persons with schizophrenia living in board and care homes

Negative emotion exhibited by the board and care providers toward residents, resident behavior, medication dosage, medication noncompliance, and gender were used to predict resident relapse over a 6-month period. Relapse was defined as movement to a higher, more intensive level of care. Eighty-four residents with a diagnosis of chronic schizophrenia disorder, living in board and care homes in the Fresno, California, area participated in the study. Board and care providers were interviewed using Kreisman's Patient Rejection Scale and Gurel's Behavior Rating Scale. Neither patient rejection nor resident behavior was predictive of relapse; however, medication noncompliance did predict relapse with the male residents and lower medication dose predicted relapse with the female residents. Rejection of the patient by the board and care operator was found to correlate .73 and .64 with negative behavior of the male and female residents respectively. Implications of these results for expressed emotion research were discussed.

Effect of muramyl dipeptide on immunogenicity of Corynebacterium pseudotuberculosis whole-cell vaccines in mice and lambs

Colostrum-deprived lambs and CF1 mice were vaccinated with water-in-oil emulsion vaccines containing nonviable whole cells (WC) of Corynebacterium pseudotuberculosis with and without muramyl dipeptide (MDP). Efficacy of vaccines was determined from the survival of mice and lesions in lambs after IV injection of 10(4) colony-forming units of C pseudotuberculosis. In mice, protection was related to the concentration of WC in the vaccine. At 50, 100, or 150 micrograms of WC, protection was good (78.8%). At 10 or 25 micrograms of WC, protection was considerably less (54.7%). At high WC concentrations, protection could only be moderately increased to 82.3% with high (50 and 100 micrograms) concentrations of MDP or increased to 90% protection with low (5 and 10 micrograms) concentrations of MDP. At low WC concentrations, protection significantly decreased to 32% (P less than 0.025) with high concentrations of MDP, but significantly increased to 72.5% (P less than 0.025) with low concentrations of MDP. Therefore, the amount of protection with lower concentrations of WC and MDP was comparable with the amount of protection with higher concentrations of WC without MDP. In lambs, high prechallenge antibody titers (geometric mean titers from 5.1 to 5.4 by day 35) were observed after vaccination with WC. Protection and vaccination site abscesses in lambs were related to the concentration of WC and MDP. Pulmonary or vaccination site abscesses were not observed in 4 of 4 lambs vaccinated with 1 mg of WC + 50 micrograms of MDP.

Serum complement activity and serum enzymes in rats after a subcutaneous injection of toxin prepared from Pasteurella multocida type D

Toxin produced by Pasteurella multocida type D was investigated for its effect on serum complement and serum biochemistry in rats. Rats were given a sublethal single subcutaneous injection of D toxin equivalent to 0.2 microgram/kg of body weight. Serum obtained 1, 3, 5 and 7 days post-treatment was tested for complement activity, total bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP). Serum complement titers were significantly elevated (P less than 0.05) at all times after injection of toxin compared to rats injected with diluent and tested at the same intervals. Bilirubin was decreased but both control and D toxin-treated rats had low concentrations of bilirubin in their sera. The other biochemical constituents measured had no consistent pattern that would indicate liver damage in the rats.

The effectiveness of flurazepam as night sedation prior to the removal of third molars

Anxiety prior to dental treatment is a well-recognized problem. Although oral sedation has been recommended the night before appointments to reduce this anxiety, there are no well-controlled studies to support this claim. The present double-blind cross-over study investigated the effect of 30 mg of flurazepam taken the night before the removal of impacted third molars. Preoperative anxiety, visuomotor performance and sleep patterns were investigated in 20 adult patients with similarly impacted third molars. While preoperative flurazepam led to a statistically significant improvement in sleep patterns, there was no reduction in pre-operative anxiety on the morning of surgery. In addition, the flurazepam-treated group demonstrated significantly impaired visuo-motor performance 60 min after intravenous sedation compared to this group where intravenous sedation was used only preceded by placebo. Patients had a significant preference for flurazepam over placebo as a night-time sedative.

Immunogenetic studies of multiple sclerosis patients in Caithness County, Scotland

The present report indicates that there is an increased frequency of HLA-B7 in multiple sclerosis patients compared to unrelated controls and unaffected siblings. HLA-A3 was not significantly increased. The increased frequency of certain HLA antigens was not reflected in increased titres of serum measles antibodies in this group. In contrast to our previous studies, there were only minimal differences in the cellular response to measles antigen in multiple sclerosis patients as compared to siblings and unrelated controls.

Microvillous surface area in secondary disaccharidase deficiency

Electron microscopy was used to measure microvillous surface area in seven small intestinal biopsies showing secondary disaccharidase deficiency and in five biopsies having normal disaccharidase levels. There were significant reductions in microvillous surface area in the enzyme deficient group, although the microvilli were not severely damaged. Histological abnormality was not always present with disaccharidase deficiency. There was no significant difference in intraepithelial lymphocyte counts between the two groups.

A collaborative day treatment program for chronic patients in adult homes

Three agencies providing services for the Nassau County (N.Y.) Department of Mental Health initiated a pilot program to provide comprehensive day treatment services to chronic psychiatric patients living in adult homes in Long Beach, New York. After screening, the clients are assigned to the regular day program of one of the centers. Two buses transport the clients to and from the centers, and a paraprofessional is assigned to each bus to encourage group discussion and interaction. The sponsoring agencies found that the original expectations for rehabilitating the clients were unrealistic. However, while clinical symptomatology was not altered, many of the clients manifested improved social behavior as the result of training in social and daily-living skills, and rates of rehospitalization were substantially reduced.

Neonatal hyperammonaemia with complete absence of liver carbamyl phosphate synthetase activity

Two newborn infants, male (A) and female (B), with lethal hyperammonaemia are described in the same family. In both, symptoms started on the second day of life. Lethargy and hypotonia were the most prominent initial findings and were followed by convulsions and coma. In both, blood ammonia levels rose to 570 mumol/u (795 microgram/100 ml) a few hours before death, which occurred on the third and fourth day of life respectively. Assay of liver urea cycle enzymes in baby B showed a complete absence of mitochondrial carbamyl phosphate synthetase activity.