A systematic review of the global prevalence of low back pain

OBJECTIVE

To perform a systematic review of the global prevalence of low back pain, and to examine the influence that case definition, prevalence period, and other variables have on prevalence.

METHODS

We conducted a new systematic review of the global prevalence of low back pain that included general population studies published between 1980 and 2009. A total of 165 studies from 54 countries were identified. Of these, 64% had been published since the last comparable review.

RESULTS

Low back pain was shown to be a major problem throughout the world, with the highest prevalence among female individuals and those aged 40-80 years. After adjusting for methodologic variation, the mean ± SEM point prevalence was estimated to be 11.9 ± 2.0%, and the 1-month prevalence was estimated to be 23.2 ± 2.9%.

CONCLUSION

As the population ages, the global number of individuals with low back pain is likely to increase substantially over the coming decades. Investigators are encouraged to adopt recent recommendations for a standard definition of low back pain and to consult a recently developed tool for assessing the risk of bias of prevalence studies.

The global burden of low back pain: estimates from the Global Burden of Disease 2010 study

OBJECTIVE

To estimate the global burden of low back pain (LBP).

METHODS

LBP was defined as pain in the area on the posterior aspect of the body from the lower margin of the twelfth ribs to the lower glutaeal folds with or without pain referred into one or both lower limbs that lasts for at least one day. Systematic reviews were performed of the prevalence, incidence, remission, duration, and mortality risk of LBP. Four levels of severity were identified for LBP with and without leg pain, each with their own disability weights. The disability weights were applied to prevalence values to derive the overall disability of LBP expressed as years lived with disability (YLDs). As there is no mortality from LBP, YLDs are the same as disability-adjusted life years (DALYs).

RESULTS

Out of all 291 conditions studied in the Global Burden of Disease 2010 Study, LBP ranked highest in terms of disability (YLDs), and sixth in terms of overall burden (DALYs). The global point prevalence of LBP was 9.4% (95% CI 9.0 to 9.8). DALYs increased from 58.2 million (M) (95% CI 39.9M to 78.1M) in 1990 to 83.0M (95% CI 56.6M to 111.9M) in 2010. Prevalence and burden increased with age.

CONCLUSIONS

LBP causes more global disability than any other condition. With the ageing population, there is an urgent need for further research to better understand LBP across different settings.

Glucagon-like peptide-1 7-36: a physiological incretin in man

The physiological role of glucagon-like peptide-1 7-36 amide (GLP-1 7-36) in man was investigated. GLP-1 7-36-like immunoreactivity was found in the human bowel; its circulating level rose after oral glucose and after a test breakfast. When it was infused into seven volunteers at a rate to mimic its postprandial plasma concentration in the fasting state, plasma insulin levels rose significantly and glucose and glucagon concentrations fell. During an intravenous glucose load, it greatly enhanced insulin release and significantly reduced peak plasma glucose concentrations, compared with a control saline infusion, even inducing postinfusion reactive hypoglycaemia. By comparison, infusion of glucose-dependent insulinotropic peptide (GIP) to physiological levels was less effective in stimulating insulin release. These observations suggest that GLP-1 7-36 is a physiological incretin and that it is more powerful than GIP. The observation of greatly increased postprandial plasma GLP-1 7-36 levels in patients with postgastrectomy dumping syndrome suggests that it may mediate the hyperinsulinaemia and reactive hypoglycaemia of this disorder.

Isolation of a tumor factor responsible for angiogenesis

Human and animal solid tumors elaborate a factor which is mitogenic to capillary endothelial cells. This factor has been called tumor-angiogenesis factor. The important components of TAF are RNA and protein. It is suggested that blockade of this factor (inhibition of angiogenesis) might arrest solid tumors at a tiny diameter of a few millimeters.

Estimating the burden of musculoskeletal disorders in the community: the comparative prevalence of symptoms at different anatomical sites, and the relation to social deprivation

BACKGROUND

Epidemiologically-based rheumatology healthcare needs assessment requires an understanding of the incidence and prevalence of musculoskeletal disorders in the community, of the reasons why people consult in primary care, and of the proportion of people who would benefit from referral to secondary care and paramedical services. This paper reports the first phase of such a needs assessment exercise.

SPECIFIC OBJECTIVE

To estimate the relative frequency of musculoskeletal pain in different, and multiple, anatomical sites in the adult population.

SETTING

Three general practices in the former Tameside and Glossop Health Authority, Greater Manchester, UK, a predominantly urban area.

DESIGN

Population survey.

METHODS

An age and sex stratified sample of 6000 adults from the three practices was mailed a questionnaire that sought data on demographic factors, musculoskeletal symptoms (pain in the past month lasting for more than a week), and physical disability (using the modified Health Assessment Questionnaire--mHAQ). The areas of pain covered were neck, back, shoulder, elbow, hand, hip, knee, and multiple joints. The Carstairs index was used as a measure of social deprivation of the postcode sector in which the person lived.

RESULTS

The response rate after two reminders was 78.5%. Non-responders were more likely to live in areas of high social deprivation. People who lived in more deprived areas were also more likely to report musculoskeletal pain, especially backpain. After adjusting for social deprivation the rates of musculoskeletal pain did not differ between the practices and so their results were combined. After adjustment for social deprivation, the most common site of pain was back (23%; 95% CI 21, 25) followed by knee (19%; 95% CI 18, 21), and shoulder (16%; 95% CI 14, 17). The majority of subjects who reported pain had pain in more than one site. The prevalence of physical disability in the community rose with age. It was highest in those with multiple joint problems but was also high in those with isolated back or knee pain.

CONCLUSION

Musculoskeletal pain is common in the community. People who live in socially deprived areas have more musculoskeletal symptoms. Estimates of the overall burden of musculoskeletal pain that combine the results of site specific surveys will be too high, those that do not adjust for socioeconomic factors will be too low.

Daily sunscreen application and betacarotene supplementation in prevention of basal-cell and squamous-cell carcinomas of the skin: a randomised controlled trial

BACKGROUND

The use of sunscreens on the skin can prevent sunburn but whether long-term use can prevent skin cancer is not known. Also, there is evidence that oral betacarotene supplementation lowers skin-cancer rates in animals, but there is limited evidence of its effect in human beings.

METHODS

In a community-based randomised trial with a 2 by 2 factorial design, individuals were assigned to four treatment groups: daily application of a sun protection factor 15-plus sunscreen to the head, neck, arms, and hands, and betacarotene supplementation (30 mg per day); sunscreen plus placebo tablets; betacarotene only; or placebo only. Participants were 1621 residents of Nambour in southeast Queensland, Australia. The endpoints after 4.5 years of follow-up were the incidence of basal-cell and squamous-cell carcinomas both in terms of people treated for newly diagnosed disease and in terms of the numbers of tumours that occurred. Analysis of the effect of sunscreen was based only on skin cancers that developed on sites of daily application. All analyses were by intention to treat.

FINDINGS

1383 participants underwent full skin examination by a dermatologist in the follow-up period. 250 of them developed 758 new skin cancers during the follow-up period. There were no significant differences in the incidence of first new skin cancers between groups randomly assigned daily sunscreen and no daily sunscreen (basal-cell carcinoma 2588 vs 2509 per 100,000; rate ratio 1.03 [95% CI 0.73-1.46]; squamous-cell carcinoma 876 vs 996 per 100,000; rate ratio 0.88 [0.50-1.56]). Similarly, there was no significant difference between the betacarotene and placebo groups in incidence of either cancer (basal-cell carcinoma 3954 vs 3806 per 100,000; 1.04 [0.73-1.27]; squamous-cell carcinoma 1508 vs 1146 per 100,000; 1.35 [0.84-2.19]). In terms of the number of tumours, there was no effect on incidence of basal-cell carcinoma by sunscreen use or by betacarotene but the incidence of squamous-cell carcinoma was significantly lower in the sunscreen group than in the no daily sunscreen group (1115 vs 1832 per 100,000; 0.61 [0.46-0.81]).

INTERPRETATION

There was no harmful effect of daily use of sunscreen in this medium-term study. Cutaneous squamous-cell carcinoma, but not basal-cell carcinoma seems to be amenable to prevention through the routine use of sunscreen by adults for 4.5 years. There was no beneficial or harmful effect on the rates of either type of skin cancer, as a result of betacarotene supplementation.

Rationale and standards for the systematic review of qualitative literature in health services research

Despite growing recognition of the need for qualitative methods in health services research, there have been few attempts to define quality standards for assessing the results. This article acknowledges the desirability of a plurality of standards. However, it is argued that three interrelated criteria can be identified as the foundation of good qualitative health research: interpretation of subjective meaning, description of social context, and attention to lay knowledge. These criteria can be examined in relation to different dimensions of any research report, including theoretical basis, sampling strategy, scope of data collection, description of data collected, and concern with generalizability or typicality. But if the concern is with the appropriateness of care and with understanding the factors that shape lay and clinical behavior, then these criteria must form the basis of a hierarchy of qualitative research evidence.

The genesis of chronic illness: narrative re-construction

In this paper I demonstrate the way in which people's beliefs about the aetiology of their particular affliction (arthritis) need to be understood as part of a more comprehensive imaginative enterprise which I refer to as narrative reconstruction. The intrinsically teleological form of this enterprise means that identified 'causes' represent only putative efficient connexions between the disease and antecedent factors but also narrative reference points between the individual and society in an unfolding process which has become profoundly disrupted. Through the presentation of case material taken from lengthy interviews I illustrate the way in which my question to the subjects about the cause of their disease: 'Why do you think you got arthritis?' was translated by them into a narrative reconstruction of their changing relationship to the world in which they live and the genesis of illness within it.

The hypothalamus and the control of energy homeostasis: different circuits, different purposes

The hypothalamus regulates many aspects of energy homeostasis, adjusting both the drive to eat and the expenditure of energy in response to a wide range of nutritional and other signals. It is becoming clear that various neural circuits operate to different degrees and probably serve specific functions under particular conditions of altered feeding behaviour. This review will discuss this functional diversity by illustrating hypothalamic neurones that express neuropeptide Y (NPY), the melanocortin-4 receptor (MC4-R) and the orexins. NPY neurones in the arcuate nucleus (ARC) release NPY, a powerful inducer of feeding and obesity, in the paraventricular nucleus (PVN) and the lateral hypothalamic area (LHA). ARC-NPY neurones are inhibited by leptin and insulin and become overactive when levels of these hormones fall during undernutrition. They may function physiologically to protect against starvation. With disruption of the inhibitory leptin signals due to gene mutations, the NPY neurones are overactive, which contributes to hyperphagia and obesity in the ob/ob and db/db mice and fa/fa Zucker rat. The MC4-R is activated by alpha-melanocyte-stimulating hormone [alpha-MSH; a cleavage product of pro-opiomelanocortin (POMC), which is expressed in the other ARC neurones] and inhibits feeding. This effect is antagonised by agouti gene-related peptide (AGRP), which is coexpressed by the ARC-NPY neurones only. Activation of MC4-R, possibly mediated by blockade of AGRP release, appears to restrain overeating of a palatable diet. This response may be programmed by a transient rise in leptin soon after presentation of palatable food, and rats that fail to do this will overeat and become obese. Orexin-A and -B (corresponding to hypocretins 1 and 2) are expressed in specific LHA neurones. These have extensive reciprocal connections with many areas involved in appetite control, including the nucleus of the solitary tracts (NTS), which relays vagal afferent satiety signals from the viscera. Orexin neurones also have close anatomical connections with LHA glucose-sensitive neurones. Orexin-A induces acute feeding but does not cause obesity. Orexin neurones are stimulated by hypoglycaemia partly via the NTS and inhibited by food ingestion. These neurones may therefore be involved in the severe hyperphagia of hypoglycaemia and short-term control of feeding.

Differing patterns of temporal atrophy in Alzheimer's disease and semantic dementia

OBJECTIVE

To characterize and quantify the patterns of temporal lobe atrophy in AD vs semantic dementia and to relate the findings to the cognitive profiles. Medial temporal lobe atrophy is well described in AD. In temporal variant frontotemporal dementia (semantic dementia), clinical studies suggest polar and inferolateral temporal atrophy with hippocampal sparing, but quantification is largely lacking.

METHODS

A volumetric method for quantifying multiple temporal structures was applied to 26 patients with probable AD, 18 patients with semantic dementia, and 21 matched control subjects.

RESULTS

The authors confirmed the expected bilateral hippocampal atrophy in AD relative to controls, with involvement of the amygdala bilaterally and the right parahippocampal gyrus. Contrary to expectations, patients with semantic dementia had asymmetric hippocampal atrophy, more extensive than AD on the left. As predicted, the semantic dementia group showed more severe involvement of the temporal pole bilaterally and the left amygdala, parahippocampal gyrus (including the entorhinal cortex), fusiform gyrus, and the inferior and middle temporal gyri. Performance on semantic association tasks correlated with the size of the left fusiform gyrus, whereas naming appeared to depend upon a wider left temporal network. Episodic memory measures, with the exception of recognition memory for faces, did not correlate with temporal measures.

CONCLUSIONS

Hippocampal atrophy is not specific for AD but is also seen in semantic dementia. Distinguishing the patients with semantic dementia was the severe global but asymmetric (left > right) atrophy of the amygdala, temporal pole, and fusiform and inferolateral temporal gyri. These findings have implications for diagnosis and understanding of the cognitive deficits in AD and semantic dementia.

A randomized controlled trial of acetyl salicylic acid in the secondary prevention of mortality from myocardial infarction

The results of a randomized controlled trial of a single daily dose of acetyl salicylic acid (aspirin) in the prevention of reinfarction in 1,239 men who had had a recent myocardial infarct were statistically inconclusive. Nevertheless, they showed a reduction in total mortality of 12% at six months and 25% at twelve months after admission to the trial. Further trials are urgently required to establish whether or not this effect is real.

Repeated occurrence of basal cell carcinoma of the skin and multifailure survival analysis: follow-up data from the Nambour Skin Cancer Prevention Trial

The aim of this study was to apply multifailure survival methods to analyze time to multiple occurrences of basal cell carcinoma (BCC). Data from 4.5 years of follow-up in a randomized controlled trial, the Nambour Skin Cancer Prevention Trial (1992-1996), to evaluate skin cancer prevention were used to assess the influence of sunscreen application on the time to first BCC and the time to subsequent BCCs. Three different approaches of time to ordered multiple events were applied and compared: the Andersen-Gill, Wei-Lin-Weissfeld, and Prentice-Williams-Peterson models. Robust variance estimation approaches were used for all multifailure survival models. Sunscreen treatment was not associated with time to first occurrence of a BCC (hazard ratio = 1.04, 95% confidence interval: 0.79, 1.45). Time to subsequent BCC tumors using the Andersen-Gill model resulted in a lower estimated hazard among the daily sunscreen application group, although statistical significance was not reached (hazard ratio = 0.82, 95% confidence interval: 0.59, 1.15). Similarly, both the Wei-Lin-Weissfeld marginal-hazards and the Prentice-Williams-Peterson gap-time models revealed trends toward a lower risk of subsequent BCC tumors among the sunscreen intervention group. These results demonstrate the importance of conducting multiple-event analysis for recurring events, as risk factors for a single event may differ from those where repeated events are considered.

Interferon beta-1b decreases the migration of T lymphocytes in vitro: effects on matrix metalloproteinase-9

In multiple sclerosis (MS), the influx of activated T lymphocytes into the brain parenchyma leads to the subsequent damage of oligodendrocytes, the cells that produce central nervous system (CNS) myelin. We report here that interferon beta-1b (IFNbeta-1b), a drug shown to be efficacious in the treatment of patients with MS, decreases the in vitro migration of activated T lymphocytes through fibronectin (FN), a major component of the basement membrane that surrounds cerebral endothelium. At 1,000 IU/ml, IFNbeta-1b reduced the migratory rate to that of unactivated T cells. In contrast, IFNgamma at 1,000 IU/ml, which caused a similar decrease (25%) in the proliferation rate of T lymphocytes as IFNbeta-1b, did not affect migration. All T-lymphocyte subsets and natural killer (NK) cells were demonstrated by flow cytometry to be equally affected by IFNbeta-1b treatment. 125I-Western blot analyses revealed that IFNbeta-1b treatment resulted in a marked reduction of the ability of T cells to cleave FN. The substrate-degrading capability of T lymphocytes was shown to be due predominantly to the activity of a 92-kd matrix metalloproteinase, MMP-9, whose levels were decreased by IFNbeta-1b. We suggest that the clinical benefits of IFNbeta-1b treatment in MS patients may be in part a result of the ability of this drug to significantly decrease MMP-9 activity, leading to a reduction of T-lymphocyte infiltration into the CNS.

Inflammatory aneurysms of the abdominal aorta

Two hundred and seventeen patients presenting with abdominal aneurysms in the Department of Surgery at the Manchester Royal Infirmary between the years 1958–69 were surveyed retrospectively.

One hundred and eighty-seven of the patients underwent operation for resection of their aneurysms; of these, 19 (10 per cent) showed excessive thickening of the aneurysm walls and perianeurysmal adhesions at operation.

Subsequent histological examination of the walls of these unusual aaneurysms showed extensive active chronic inflammatory changes, including plasma-cell infiltration.

This group of patients whose aneurysms we describe as ‘inflammatory’ presented with different clinical features in comparison with the atherosclerotic group.

Retrospective investigation has not yet revealed any aetiological factors. We feel that ‘inflammatory’ aneurysms are a discrete entity with significant differences from atherosclerotic aneurysms and previously described arteritis.

Heat Wave and Mortality: A Multicountry, Multicommunity Study

BACKGROUND

Few studies have examined variation in the associations between heat waves and mortality in an international context.

OBJECTIVES

We aimed to systematically examine the impacts of heat waves on mortality with lag effects internationally.

METHODS

We collected daily data of temperature and mortality from 400 communities in 18 countries/regions and defined 12 types of heat waves by combining community-specific daily mean temperature ≥90th, 92.5th, 95th, and 97.5th percentiles of temperature with duration ≥2, 3, and 4 d. We used time-series analyses to estimate the community-specific heat wave-mortality relation over lags of 0-10 d. Then, we applied meta-analysis to pool heat wave effects at the country level for cumulative and lag effects for each type of heat wave definition.

RESULTS

Heat waves of all definitions had significant cumulative associations with mortality in all countries, but varied by community. The higher the temperature threshold used to define heat waves, the higher heat wave associations on mortality. However, heat wave duration did not modify the impacts. The association between heat waves and mortality appeared acutely and lasted for 3 and 4 d. Heat waves had higher associations with mortality in moderate cold and moderate hot areas than cold and hot areas. There were no added effects of heat waves on mortality in all countries/regions, except for Brazil, Moldova, and Taiwan. Heat waves defined by daily mean and maximum temperatures produced similar heat wave-mortality associations, but not daily minimum temperature.

CONCLUSIONS

Results indicate that high temperatures create a substantial health burden, and effects of high temperatures over consecutive days are similar to what would be experienced if high temperature days occurred independently. People living in moderate cold and moderate hot areas are more sensitive to heat waves than those living in cold and hot areas. Daily mean and maximum temperatures had similar ability to define heat waves rather than minimum temperature. https://doi.org/10.1289/EHP1026.

Hypothalamic orexin expression: modulation by blood glucose and feeding

Orexins (hypocretins), novel peptides expressed in specific neurons of the lateral hypothalamic area (LHA), stimulate feeding when injected intracerebroventricularly. We investigated their role in feeding in the rat by measuring hypothalamic prepro-orexin mRNA levels under contrasting conditions of increased hunger. Prepro-orexin mRNA levels increased significantly after 48 h of fasting (by 90-170%; P < 0.05) and after acute (6 h) hypoglycemia when food was withheld (by 90%; P < 0.02). By contrast, levels were unchanged during chronic food restriction, streptozotocin-induced diabetes, hypoglycemia when food was available, voluntary overconsumption of palatable food, or glucoprivation induced by systemic 2-deoxy-D-glucose. Orexin expression was not obviously related to changes in body weight, insulin, or leptin, but was stimulated under conditions of low plasma glucose in the absence of food. Orexins may participate in the short-term regulation of energy homeostasis by initiating feeding in response to falls in glucose and terminating it after food ingestion. The LHA is known to contain neurons that are stimulated by falls in circulating glucose but inhibited by feeding-related signals from the viscera; orexin neurons may correspond to this neuronal population.

Interferon beta in the treatment of multiple sclerosis: mechanisms of action

Interferon beta (IFN-beta) has been shown in several clinical trials to have efficacy in MS. Its mechanism of action, however, remains unclear. In this review, several biological activities of IFN-beta are highlighted, including its inhibitory effects on proliferation of leukocytes and antigen presentation. Furthermore, IFN-beta may modulate the profile of cytokine production toward that of the anti-inflammatory phenotype, and this appears to occur in the systemic circulation and within the CNS. Finally, IFN-beta can reduce T-cell migration by inhibiting the activity of T-cell matrix metalloproteinases. These activities are likely to act in concert to account for the mechanism of IFN-beta in MS.

A cancer risk assessment of di(2-ethylhexyl)phthalate: application of the new U.S. EPA Risk Assessment Guidelines

The current United States Environmental Protection Agency (EPA) classification of di(2-ethylhexyl)phthalate (DEHP) as a B2 "probable human" carcinogen is based on outdated information. New toxicology data and a considerable amount of new mechanistic evidence were used to reconsider the cancer classification of DEHP under EPA's proposed new cancer risk assessment guidelines. The total weight-of-evidence clearly indicates that DEHP is not genotoxic. In vivo administration of DEHP to rats and mice results in peroxisome proliferation in the liver, and there is strong evidence and scientific consensus that, in rodents, peroxisome proliferation is directly associated with the onset of liver cancer. Peroxisome proliferation is a transcription-mediated process that involves activation by the peroxisome proliferator of a nuclear receptor in rodent liver called the peroxisome proliferator-activated receptor (PPARalpha). The critical role of PPARalpha in peroxisomal proliferation and carcinogenicity in mice is clearly established by the lack of either response in mice genetically modified to remove the PPARalpha. Several mechanisms have been proposed to explain how, in rodents, peroxisome proliferation can lead to the formation of hepatocellular tumors. The general consensus of scientific opinion is that PPARalpha-induced mitogenesis and cell proliferation are probably the major mechanisms responsible for peroxisome proliferator-induced hepatocarcinogenesis in rodents. Oxidative stress appears to play a significant role in this increased cell proliferation. It triggers the release of TNFalpha by Kupffer cells, which in turn acts as a potent mitogen in hepatocytes. Rats and mice are uniquely responsive to the morphological, biochemical, and chronic carcinogenic effects of peroxisome proliferators, while guinea pigs, dogs, nonhuman primates, and humans are essentially nonresponsive or refractory; Syrian hamsters exhibit intermediate responsiveness. These differences are explained, in part, by marked interspecies variations in the expression of PPARalpha, with levels of expression in humans being only 1-10% of the levels found in rat and mouse liver. Recent studies of DEHP clearly indicate a nonlinear dose-response curve that strongly suggests the existence of a dose threshold below which tumors in rodents are not induced. Thus, the hepatocarcinogenic effects of DEHP in rodents result directly from the receptor-mediated, threshold-based mechanism of peroxisome proliferation, a well-understood process associated uniquely with rodents. Since humans are quite refractory to peroxisomal proliferation, even following exposure to potent proliferators such as hypolipidemic drugs, it is concluded that the hepatocarcinogenic response of rodents to DEHP is not relevant to human cancer risk at any anticipated exposure level. DEHP should be classified an unlikely human carcinogen with a margin of exposure (MOE) approach to risk assessment. The most appropriate and conservative point of reference for assessing MOEs should be 20 mg/kg/day, which is the mouse NOEL for peroxisome proliferation and increased liver weight. Exposure of the general human population to DEHP is approximately 30 microg/kg body wt/day, the major source being from residues in food. Higher exposures occur occupationally [up to about 700 microg/kg body wt/day (mainly by inhalation) based on current workplace standards] and through use of certain medical devices [e.g., up to 457 microg/kg body wt/day for hemodialysis patients (intravenous)], although these have little relevance because the routes of exposure bypass critical activation enzymes in the gastrointestinal tract.

Emergence of vancomycin-resistant enterococci in New York City

Enterococci, a common cause of nosocomial infection, are intrinsically resistant to most antimicrobials and readily acquire additional resistance. Vancomycin-resistant enterococci (VRE) have caused clusters of nosocomial infections since 1988. In April, 1991, the New York City Department of Health asked all city laboratories to submit suspected VRE isolates for confirmation. Clinical and epidemiological characteristics of the first 100 patients with VRE were identified, and antimicrobial susceptibility testing, restriction enzyme analysis, and DNA-DNA hybridisation with the vanA gene probe were done. From September, 1989, to October, 1991, 361 patients with VRE were identified at 38 hospitals. The number of hospitals reporting VRE increased from 1 in 1989 to 38 by October, 1991. 98% of 100 VRE infections were nosocomially acquired and 83% patients had received vancomycin and/or a cephalosporin in the 30 days before isolation of VRE. Of 23 isolates from 21 of the first 100 patients, 19 (83%) were resistant to all available antimicrobials. Four vanA probing patterns were noted, and restriction enzyme analysis of the 23 isolates revealed 14 strains. VRE have emerged rapidly in New York City. Molecular analyses suggest that a highly mobile genetic element--eg, a transposon--is responsible for the rapid spread of vancomycin resistance.

Developmental regulation of IgM secretion: the role of the carboxy-terminal cysteine

B lymphocytes do not secrete IgM, and plasma cells only secrete IgM polymers. Here we show that both events are attributable to the tailpiece found at the carboxyl terminus of mus chains, and we specifically implicate Cys-575. Thus, if Cys-575 was mutated, IgM was secreted by B cells. Similarly, a mutant IgG containing a mus tailpiece became largely retained within the cell; secretion was restored upon mutation of the tailpiece cysteine. Removal of Cys-575 also allowed hypersecretion of monomeric IgM by plasmacytoma cells. Following further removal of Cmu1, heavy chains were secreted in the absence of light chains. Thus, in B and plasma cells, Cys-575 is involved both in the polymerization of IgM and in intracellular retention of unpolymerized intermediates.

Essential fatty acids and fetal brain growth

The fetal brain accumulates long-chain (C20 and 22) polyunsaturated fatty acids--arachidonic and docosahexaenoic--during cell division. De-novo synthesis of these acids does not occur and they are thought to be either directly derived from food or by metabolism from linoleic and linolenic acids, respectively. Administration of isotopically labelled linoleic and linolenic acids to pregnant guineapigs showed that only a small proportion of the label was converted to their respective long-chain polyunsaturated derivatives in the maternal liver. The proportion was increased within the phospholipids (structural lipids) by what appeared to be amultiple processing system which increased chain length and degree of polyunsaturation from maternal liver to placenta, fetal liver, and to fetal brain. Observations in man suggest a similar trend. The porportion of long-chain polyunsaturated acids increased in the phospholipids from maternal blood, cord blood, fetal liver, and fetal brain. These data show that the placenta and fetus are radically modifying the maternal phospholipids so as to achieve the high proportions of the C20 and C22 polyunsaturated fatty acids in the structural lipids of the developing brain.

Psychotic-like experiences in major depression and anxiety disorders: a population-based survey in young adults

OBJECTIVE

Population-based surveys have confirmed that psychotic-like experiences are prevalent in the community. However, it is unclear if these experiences are associated with common mental disorders. The aim of this study was to examine the prevalence of psychotic-like experiences in those with affective and anxiety disorders.

METHODS

Subjects were drawn from the Mater-University of Queensland Study of Pregnancy. Delusion-like experiences were assessed with the Peters Delusional Inventory (PDI). The Composite International Diagnostic Interview (CIDI) was used to identify individuals with Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) lifetime diagnoses of major depression, anxiety disorder, substance use/dependence, and psychotic disorders. The influence of affective and anxiety disorders on PDI and CIDI psychosis-related items' scores were assessed with logistic regression, with adjustments for age, sex, and the presence of the other comorbid psychiatric diagnoses.

RESULTS

Having either a lifetime diagnosis of major depressive disorder or an anxiety disorder was associated with significantly higher PDI total scores (highest vs lowest quartile adjusted odds ratios [ORs] and 95% confidence intervals [CIs] = 4.43, 3.09-6.36; 3.08, 2.26-4.20, respectively). The odds of endorsing any CIDI hallucination or delusion item was increased in those with a major depressive or anxiety disorder. The presence of current anxiety disorder symptoms was significantly associated with PDI score (OR = 5.81, 95% CI = 3.68-9.16).

CONCLUSION

While psychotic-like experiences are usually associated with psychotic disorders, individuals with depression and anxiety are also more likely to report these symptoms compared with well individuals. Psychotic-like experiences are associated with a range of common mental disorders.