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.

International Harmonization of Nomenclature and Diagnostic Criteria (INHAND): Progress to Date and Future Plans

The International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice proposal (INHAND) has been operational since 2005. A Global Editorial Steering Committee manages the overall objectives of the project, and the development of harmonized terminology for each organ system is the responsibility of the Organ Working Groups, drawing upon experts from North America, Europe, and Japan. Great progress has been made with 9 systems published to date--respiratory, hepatobiliary, urinary, central/peripheral nervous systems, male reproductive and mammary, zymbals, clitoral, and preputial glands in Toxicologic Pathology and the integument and soft tissue and female reproductive in the Journal of Toxicologic Pathology as supplements and on a Web site--www.goReni.org. INHAND nomenclature guides offer diagnostic criteria and guidelines for recording lesions observed in rodent toxicity and carcinogenicity studies. The guides provide representative photomicrographs of morphologic changes, information regarding pathogenesis, and key references. The purpose of this brief communication is to provide an update on the progress of INHAND.

Development and testing of a field diagnostic assay for peste des petits ruminants virus

We have developed an immunochromatographic test for the diagnosis of peste des petits ruminants (PPR) under field conditions. The diagnostic assay has been tested in the laboratory and also under field conditions in Ivory Coast, Pakistan, Ethiopia and Uganda. The test is carried out on a superficial swab sample (ocular or nasal) and showed a sensitivity of 84% relative to PCR. The specificity was 95% over all nasal and ocular samples. The test detected as little as 10³ TCID₅₀ (50% tissue culture infectious doses) of cell culture-grown virus, and detected virus isolates representing all four known genetic lineages of peste des petits ruminants virus. Virus could be detected in swabs from animals as early as 4 days post-infection, at a time when clinical signs were minimal. Feedback from field trials was uniformly positive, suggesting that this diagnostic tool may be useful for current efforts to control the spread of PPR.

The passive mechanical properties of muscle and their adaptations to altered patterns of use

The length and stiffness of a relaxed muscle are determined by the mechanical properties of its intramuscular connective tissue and/or intracellular structures. Viscous deformation of these components of muscle is responsible for the increase in muscle length seen immediately after stretching, but this increase is transient. Lasting changes in muscle length can only be brought about by adaptations of the structure of muscle. An understanding of the nature of the stimulus for muscle to adapt can provide therapists with a theoretical basis for therapeutic intervention aimed at producing changes in muscle length.

Dimensional structure and course of post-traumatic stress symptomatology in World Trade Center responders

BACKGROUND

Post-traumatic stress disorder (PTSD) in response to the World Trade Center (WTC) disaster of 11 September 2001 (9/11) is one of the most prevalent and persistent health conditions among both professional (e.g. police) and non-traditional (e.g. construction worker) WTC responders, even several years after 9/11. However, little is known about the dimensionality and natural course of WTC-related PTSD symptomatology in these populations.

METHOD

Data were analysed from 10 835 WTC responders, including 4035 police and 6800 non-traditional responders who were evaluated as part of the WTC Health Program, a clinic network in the New York area established by the National Institute for Occupational Safety and Health. Confirmatory factor analyses (CFAs) were used to evaluate structural models of PTSD symptom dimensionality; and autoregressive cross-lagged (ARCL) panel regressions were used to examine the prospective interrelationships among PTSD symptom clusters at 3, 6 and 8 years after 9/11.

RESULTS

CFAs suggested that five stable symptom clusters best represent PTSD symptom dimensionality in both police and non-traditional WTC responders. This five-factor model was also invariant over time with respect to factor loadings and structural parameters, thereby demonstrating its longitudinal stability. ARCL panel regression analyses revealed that hyperarousal symptoms had a prominent role in predicting other symptom clusters of PTSD, with anxious arousal symptoms primarily driving re-experiencing symptoms, and dysphoric arousal symptoms primarily driving emotional numbing symptoms over time.

CONCLUSIONS

Results of this study suggest that disaster-related PTSD symptomatology in WTC responders is best represented by five symptom dimensions. Anxious arousal symptoms, which are characterized by hypervigilance and exaggerated startle, may primarily drive re-experiencing symptoms, while dysphoric arousal symptoms, which are characterized by sleep disturbance, irritability/anger and concentration difficulties, may primarily drive emotional numbing symptoms over time. These results underscore the importance of assessment, monitoring and early intervention of hyperarousal symptoms in WTC and other disaster responders.

Trajectories of PTSD risk and resilience in World Trade Center responders: an 8-year prospective cohort study

BACKGROUND

Longitudinal symptoms of post-traumatic stress disorder (PTSD) are often characterized by heterogeneous trajectories, which may have unique pre-, peri- and post-trauma risk and protective factors. To date, however, no study has evaluated the nature and determinants of predominant trajectories of PTSD symptoms in World Trade Center (WTC) responders.

METHOD

A total of 10835 WTC responders, including 4035 professional police responders and 6800 non-traditional responders (e.g. construction workers) who participated in the WTC Health Program (WTC-HP), were evaluated an average of 3, 6 and 8 years after the WTC attacks.

RESULTS

Among police responders, longitudinal PTSD symptoms were best characterized by four classes, with the majority (77.8%) in a resistant/resilient trajectory and the remainder exhibiting chronic (5.3%), recovering (8.4%) or delayed-onset (8.5%) symptom trajectories. Among non-traditional responders, a six-class solution was optimal, with fewer responders in a resistant/resilient trajectory (58.0%) and the remainder exhibiting recovering (12.3%), severe chronic (9.5%), subsyndromal increasing (7.3%), delayed-onset (6.7%) and moderate chronic (6.2%) trajectories. Prior psychiatric history, Hispanic ethnicity, severity of WTC exposure and WTC-related medical conditions were most strongly associated with symptomatic trajectories of PTSD symptoms in both groups of responders, whereas greater education and family and work support while working at the WTC site were protective against several of these trajectories.

CONCLUSIONS

Trajectories of PTSD symptoms in WTC responders are heterogeneous and associated uniquely with pre-, peri- and post-trauma risk and protective factors. Police responders were more likely than non-traditional responders to exhibit a resistant/resilient trajectory. These results underscore the importance of prevention, screening and treatment efforts that target high-risk disaster responders, particularly those with prior psychiatric history, high levels of trauma exposure and work-related medical morbidities.

Nurse-delivered universal point-of-care testing for HIV in an open-access returning traveller clinic

BACKGROUND

Early diagnosis of HIV infection reduces morbidity and mortality associated with late presentation. Despite UK guidelines, the HIV testing rate has not increased. We have introduced universal HIV screening in an open-access returning traveller clinic.

METHODS

Data were prospectively recorded for all patients attending the open-access returning traveller clinic between August 2008 and December 2010. HIV testing was offered to all patients from May 2009; initially testing with laboratory samples (phase 1) and subsequently a point-of-care test (POCT) (phase 2).

RESULTS

A total of 4965 patients attended the clinic; 1342 in phase 0, 792 in phase 1 and 2831 in phase 2. Testing rates for HIV increased significantly from 2% (38 of 1342) in phase 0 to 23.1% (183 of 792) in phase 1 and further increased to 44.5% (1261 of 2831) during phase 2 (P < 0.0001). Two new diagnoses of HIV-1 were identified in phase 1 (1.1% of tested); seven patients had a reactive POCT test in phase 2, of whom five (0.4% of those tested) were confirmed in a 4th generation assay. The patients with false reactive tests had a concurrent Plasmodium falciparum infection. Patients travelling to the Middle East and Europe were less likely to accept an HIV test with POCT.

CONCLUSIONS

A nurse-delivered universal point-of-care HIV testing service has been successfully introduced and sustained in an acute medical clinic in a low-prevalence country. Caution is required in communicating reactive results in low-prevalence settings where there may be alternative diagnoses or a low population prevalence of HIV infection.

Trastuzumab use and CNS metastasis in Medicare patients diagnosed with metastatic breast cancer (MBC)

1123

Background: While trastuzumab was approved in 1998 for treating patients with HER-2-positive MBC, there is little information on its use in the Medicare setting. Methods: We used SEER-Medicare data to examine patterns of trastuzumab use in women diagnosed with MBC . An index date was defined as either the date of diagnosis (stage IV) or of first distant recurrence (stage 0-III). Included patients were diagnosed in 2000–2002, and had their first claim for trastuzumab between their index date and December 31, 2005, the end of the observation period. Patients were divided into those who received trastuzumab as part of their first treatment following their index date (Group A), and those who began trastuzumab after at least one course of chemotherapy (Group B). Chemotherapy agents were grouped into antimicrotubule (vinorelbine, docetaxel, paclitaxel, vincristine), anthracycline (doxorubicin, epirubicin), cyclophosphamide, other, and unknown. Results: 281 patients met the inclusion criteria. Overall, the median (mean) time from the index date to initial chemotherapy and/or trastuzumab treatment was 35 (94) days (range 1–1,587 days). The average duration of trastuzumab use (first to last administration) was 371 days (median 239), during which patients averaged 2.3 trastuzumab claims per month. There were 192 (68%) patients in Group A. The median (mean) time from diagnosis to initial treatment in Group A was 34 (94) days. 64 (33%) received trastuzumab alone, and 121 (63%) received trastuzumab with an antimicrotubule. In Group B (89 patients), the median (mean) time to initial chemotherapy was 41 (92) days. 36 (40%) received anthracycline and/or cyclophosphamide based therapy, 22 (25%) received an antimicrotubule without either an anthracycline or cyclophosphamide. The median (mean) time from initial chemotherapy to initial trastuzumab therapy was 233 (368) days. At that time, 29 (33%) received trastuzumab alone, and 54 (61%) received trastuzumab plus an antimicrotubule. Conclusions: To our knowledge, this is the first study to describe patterns of trastuzumab use in Medicare. When used for metastatic breast cancer, trastuzumab was most often provided soon after diagnosis as part of initial treatment, and usually with an antimicrotubule agent.

[Table: see text]

Idiopathic chondrolysis condition in two young, wild-caught Cynomolgus monkeys (Macaca fascicularis) reared in captivity

Idiopathic chondrolysis is a human clinical entity typically reported in adolescent individuals. In this brief communication, we report 2 cases of presumptive idiopathic chondrolysis of the femoral head in Cynomolgus macaques and discuss the clinical symptomatology and pathology of the disease. In detail, we describe the histomorphologic changes of idiopathic chondrolysis and compare these findings with those typically observed in the primary differential diagnoses of Legg-Calve-Perthes disease and nonspecific osteoarthritis. Consideration of this entity among differential diagnoses in young Cynomolgus macaques with unilateral osteoarthritis could be important both for laboratory animal veterinarians and pathologists.

Abdominal diameter index: a more powerful anthropometric measure for prevalent coronary heart disease risk in adult males

AIM

The authors wished to compare the strength of association of several anthropometric measures of body size and fat distribution among themselves and in comparison with other known risk factors for prevalent coronary heart disease (CHD).

METHODS

Prevalent CHD was assessed in 466 middle-aged, male, multiracial Triborough Bridge and Tunnel Authority officers in New York City by verified history, electrocardiogram or exercise stress test. Anthropometric measures included body mass index, waist, hip and thigh circumferences, waist-hip ratio, waist-thigh ratio, sagittal abdominal diameter and abdominal diameter index (sagittal abdominal diameter/thigh circumference). Results were compared with other CHD risk factors measured simultaneously (history of diabetes, smoking, blood pressure, lipid profile, apolipoproteins A and B, lipoprotein (a), homocysteine, fibrinogen, urinary microalbumin, serum vitamin E and ferritin) and a calculated 10-year CHD risk using a Framingham algorithm (10-year Framingham CHD risk).

RESULTS

CHD was found in 29 individuals. Of the six anthropometric measures, abdominal diameter index gave the largest and most significant standardized odds ratio (OR) for CHD [1.80, 95% confidence interval (CI) 1.20, 2.71], equivalent to 10-year Framingham CHD risk. Men in the highest compared with the lowest tertile of abdominal diameter index had a univariate OR of 5.47 (95% CI 1.55, 19.28) which was the only anthropometric measure that remained significant after adjusting for 10-year Framingham CHD risk.

CONCLUSIONS

For middle-aged American men, abdominal diameter index may be the most powerful anthropometric measure of risk for prevalent CHD.

Asthma hospitalization trends in Charleston, South Carolina, 1956 to 1997: twenty-fold increase among black children during a 30-year period

OBJECTIVE

The increase in asthma prevalence has been documented worldwide, affecting many races living in many different climates. Multiple studies have demonstrated that the most striking prevalence and morbidity of asthma in the United States has been in black children, but little research has determined the scale of the increase, or specifically when the disease became severe in this group. This study sought to determine exactly when the rise in asthma hospitalizations among black patients began and what the pattern of asthma hospitalizations has been in different races and age groups over a 40-year period in 1 urban area.

METHODS

A retrospective chart review of discharges from the Medical University of South Carolina was conducted from 1956 to 1997. Charts with the primary discharge diagnosis of asthma were examined for discharge date, race, and age group (0- to 4-year-olds, 5- to 18-year-olds, 19- to 50-year-olds, > or =51-year-olds). The diagnostic codes used were based on the International Classification of Diseases (ICD)-6, 1956-1957; ICD-7, 1958-1967; ICD-8, 1968-1978; and ICD-9, 1979-1997. Over the period studied, this hospital was the primary inpatient provider for children in this area, and the only provider for uninsured children. Between 1960 and 1990, the racial makeup of the area remained stable, as did the percentage of blacks living at the poverty level. The raw number of asthma discharges, rate per 10 000 discharges of the same race, and rate per 100 000 population in Charleston County were tabulated for each age group and racial category.

RESULTS

Over the time period examined, there has been a progressive increase in asthma hospitalizations in black individuals of all age groups and in whites under 18 years. The most striking increase has been in black children 0 to 18 years old (figure). The increase either as raw values or as a rate per 100 000 began around 1970, and was linear. This increase in black children discharged with asthma as a rate per 100 000 population was 20-fold: the rate increased from 18 in 1970 to 370 in 1997. Asthma discharges as a rate per 10 000 black children discharged increased by 24-fold from 1960 to 1997. Total discharges from the hospital increased from 49 000 to 128 000 per year over this period. Blacks made up only 28% of discharges in 1957, but that proportion increased to 56% in 1960 and remained relatively stable over the following 35 years. The increase seen in white children 0 to 18 years of age as a rate per 100 000 population was 5-fold and began around 1980. Both increases seem to be consistent over the time period studied, and continued to 1997. [figure: see text].

CONCLUSIONS

Among a predominantly poor black population living in a southern US city, there has been a steady increase in childhood asthma hospitalizations over the past 30 years. A significant although less dramatic rise has occurred in white children. Over this time period, although there have been many changes in lifestyle that could have contributed to this rise, there have been no major changes in housing conditions for poor patients. In addition, Medicaid coverage for children in South Carolina did not change significantly until 1999. The time course of these increases parallels increases reported in other Western populations, suggesting that there must be 1 or more common factors contributing to the rise. Many explanations have been offered for the changes in incidence and severity of asthma. The scale of the change, time course, and linearity of the increase in this study represent a challenge to many of the hypotheses proposed to explain this epidemic.

Impact of a joint labor-management ergonomics program on upper extremity musculoskeletal symptoms among garment workers

This study evaluated the effect of an ergonomics intervention program on the prevalence and intensity of symptoms of upper extremity work-related musculoskeletal disorders among 36 garment workers performing an operation called spooling. Adjustable chairs were introduced and workers were trained in their use. Symptom surveys were administered prior to and 6 months after introduction of adjustable chairs. Quantitative pre- and post-intervention measurement of joint position was performed utilizing videotapes among a subgroup of nineteen. Eighty nine percent of the cohort reported pain in either the neck or at least one upper extremity anatomic site prior to the adjustable chair intervention. Among subjects reporting pain at baseline, there were significantly decreased pain levels in 10 of 11 anatomic sites after the intervention. Among all subjects, the proportion reporting pain decreased for each anatomic site following the intervention, with statistically significant decreases in 3 sites. However, there were only modest declines in awkward posture among the videotaped subgroup. This study suggests that introduction of an ergonomics program focused on education and introduction of an adjustable chair may diminish musculoskeletal symptomatology in apparel manufacturing workers.

Toxicity and carcinogenicity study in F344 rats following 2 years of whole-body exposure to naphthalene vapors

The toxicologic and carcinogenic potential of naphthalene was studied by exposing groups of 49 male and 49 female F344 rats to atmospheres containing 0, 10, 30, or 60 ppm of the chemical for 6 h daily, 5 days/wk for 2 yr. Mean body weights of exposed groups of male rats were less than for the control group throughout most of the study. Mean body weights of exposed female rats were generally similar to those of controls. Survival of exposed and control rats was similar. Under the conditions of this 2-yr inhalation study, naphthalene was carcinogenic to male and female F344/N rats, causing increased incidences of respiratory epithelial adenoma (males: control, 0%; low dose, 12%, mid dose, 17%; high dose, 31%; females: 0%; 0%; 8%; 4%) and olfactory epithelial neuroblastoma (males: control, 0%; low dose, 0%; mid dose, 8%; high dose, 6%; females: 0; 4%; 6%; 24%) of the nose. In both sexes of rats, exposure to naphthalene also caused significant increases in the incidences of nasal lesions including hyperplasia, atrophy, chronic inflammation, and hyaline degeneration of the olfactory epithelium and hyperplasia; squamous metaplasia, hyaline degeneration, and goblet-cell hyperplasia of the respiratory epithelium; and glandular hyperplasia and squamous metaplasia.

Occupational health problems of bridge and tunnel officers

Bridge and tunnel officers (BTOs) sustain potential exposure to a number of physical, chemical, and work-organizational factors. They are at risk for both fatal and non-fatal occupational injuries due to moving vehicles, workplace violence, vehicular fires, and physical hazards, such as slippery walking surfaces due to oil or ice on roadways. This chapter describes the spectrum of occupational injuries and illnesses which may be seen in BTOs, focusing on: 1) vehicular exhaust and air pollution, 2) ergonomic hazards, 3) job strain, 4) noise, 5) blood-borne pathogens, 6) chemicals used in road work and maintenance (e.g., lead-based paint), and 7) with the recent advent of electronic traffic sensors, microwave radiation. Special emphasis is given to respiratory disease and cardiovascular disease. Finally, some recommendations for focused health surveillance and preventive efforts in this population are made.

The development of a self-directed and peer-based clinical training programme

A reflective learning approach for clinical training with final year students is described. The training programme aims to promote the development of independent and reflective practitioners. The theories and ideas that have influenced the structure of the programme are described and an outline of the programme is provided. The views of students who have participated in the process are discussed. Most students were positive about their experiences, but some problems were reported. Suggestions for improving the supervisory process are considered.

Treatment of word retrieval in aphasia: generalisation to conversational speech

The question of whether treatment gains in picture naming generalise to conversation remains relatively unexplored. Several difficulties surround data collection and analysis. A quantitative measure of word retrieval in aphasia is presented along with relevant details relating to the reliability of the measure, and the relationship between word retrieval in picture naming and noun retrieval in conversation. We discuss the clinical application of the measure and its applicability outside the field of aphasia.

Phonological and orthographic approaches to the treatment of word retrieval in aphasia

We present a preliminary report on a study of the treatment of word finding difficulties in aphasia using phonological and orthographic cues. These techniques although often used to cue word finding in the immediate term have been little evaluated in terms of therapy designed to improve word retrieval in the long term. The first phase using cued word retrieval in a picture naming task was followed by a second phase designed to facilitate use of treated words in real-life contexts. The results from both phases were encouraging with improved word retrieval for three out of the four participants. The implications for clinical practice are discussed.

3-(4-Piperidinyl)- and 3-(8-aza-bicyclo[3.2.1]oct-3-yl)-2-phenyl-1H-indoles as bioavailable h5-HT2A antagonists

A series of 3-(4-piperidinyl)- and 3-(8-aza-bicyclo[3.2.1]oct-3-yl)-2-phenyl-1H-indoles have been prepared and evaluated as ligands for the h5-HT2A receptor. 3-(8-Phenethyl-8-aza-bicyclo[3.2.1]oct-3-yl)-2-phenyl-1H-indole is a high-affinity (1.2nM), selective (>800 fold over h5-HT2C and hD2 receptors) antagonist at the h5-HT2A receptor with oral bioavailability in rats.

Modulation of arachidonate and docosahexaenoate in Morone chrysops larval tissues and the effect on growth and survival

The extent to which extreme dietary levels of arachidonate (AA) and/or docosahexaenoate (DHA) modulate lipid composition in the body tissues and consequently affect growth and survival in freshwater Morone larvae species was examined. White bass, M. chrysops, larvae (day 24-46) were fed Artemia nauplii enriched with algal oils containing varying proportions of AA and DHA (from 0 to over 20% the total fatty acids). Growth was significantly reduced (P< 0.05) in larvae fed a DHA-deficient Artemia diet. Increases in dietary levels of AA also were associated with a significant growth reduction. However, the inhibitory effect of AA on larvae growth could be suppressed by the dietary addition of DHA (at a level of 21.6% of the total fatty acids in enrichment lipids). Larval brain + eyes tissue accumulated over 10 times more DHA than AA in its structural lipids (phosphatidylcholine, phosphatidylethanolamine) at any dietary ratio. In contrast, DHA accumulation, as compared to AA, in gill lipids declined considerably at higher than 10:1 DHA/AA tissue ratios. DHA and eicosapentaenoic acid (EPA) contents in brain + eyes tissue were most sensitive to competition from dietary AA, being displaced from the tissue at rates of 0.36 +/- 0.07 mg DHA and 0.46 +/- 0.11 mg EPA per mg increase in tissue AA, and 0.55 +/- 0.14 mg AA per mg increase in tissue DHA. On the other hand, AA and EPA levels in gill tissue were most sensitive to dietary changes in DHA levels; AA was displaced at rates of 0.37 +/- 0.11 mg, whereas EPA increased at rates of 0.68 +/- 0.28 mg per mg increase in tissue DHA. Results suggest that balanced dietary DHA/AA ratios (that allow DHA/AA ratios of 2.5:1 in brain + eyes tissue) promote a high larval growth rate, which also correlates with maximal regulatory response in tissue essential fatty acids.

The hind wing of the desert locust (Schistocerca gregaria Forskal). II. Mechanical properties and functioning of the membrane

As part of an investigation of the functional mechanics of the hind wing of the desert locust Schistocerca gregaria, the Young's modulus of the membrane was measured using a newly developed universal materials test machine capable of testing very small specimens of cuticle, down to 1 mm gauge length. Strain was measured optically. Specimens were cut from various locations around the wing and tested under controlled temperature and humidity. The modulus of the membrane was typically between 1 and 5 GPa, but both this and the membrane thickness varied around the wing, with the remigium and the anal fan showing markedly different properties. The membrane was tested for chitin using two methods: a gas pyrolysis/mass spectrometry assay, and a gold-labelled immunoassay specific to chitin. None was detected, and the membrane may consist of epicuticle alone. The wings were examined for evidence of crystalline material using standard polarising microscopy and an advanced technique that distinguishes between three components of the polarised image. Birefringence was detected in the membrane of the anterior part of the wing, but vanished when the membrane was separated from the surrounding veins, suggesting that it was due to pre-stress rather than to ultrastructure. The implications are discussed.

The hind wing of the desert locust (Schistocerca gregaria Forskal). I. Functional morphology and mode of operation

Detailed morphological investigation, mechanical testing and high-speed cinematography and stroboscopic examination of desert locusts, Schistocerca gregaria, in flight show that their hind wings are adapted to deform cyclically and automatically through the wing stroke and that the deformations are subtly dependent on the wings' structure: their shape, venation and vein design and the local properties of the membrane. The insects predominantly fly fast forwards, generating most force on the downstroke, and the hind wings generate extra lift by peeling apart at the beginning of the downstroke and by developing a cambered section during the stroke's translation phase through the ‘umbrella effect’ - an automatic consequence of the active extension of the wings' expanded posterior fan. Bending experiments indicate that most of the hind wing is more rigid to forces from below than from above and demonstrate that the membrane acts as a stressed skin to stiffen the structure.

Two-year toxicity and carcinogenicity study of methyleugenol in F344/N rats and B6C3F(1) mice

Methyleugenol (MEG) was tested for toxicity/carcinogenicity in a 2-yr carcinogenesis bioassay because of its widespread use in a variety of foods, beverages, and cosmetics as well as its structural resemblance to the known carcinogen safrole. F344/N rats and B6C3F(1) mice (50 animals/sex/dose group) were given MEG suspended in 0.5% methylcellulose by gavage at doses of 37, 75, or 150 mg/kg/day for 2 yr. Control groups (60 rats/sex and 50 mice/sex) received only the vehicle. A stop-exposure group of 60 rats/sex received 300 mg/kg/day by gavage for 53 weeks followed by the vehicle only for the remaining 52 weeks of the study. A special study group (10 animals/sex/species/dose group) were used for toxicokinetic studies. All male rats given 150 and 300 mg/kg/day died before the end of the study; survival of female rats given 150 mg/kg/day and all treated female mice was decreased. Mean body weights of treated male and female rats and mice were decreased when compared to control. Area under the curve results indicated that greater than dose proportional increases in plasma MEG occurred for male 150 and 300 mg/kg/day group rats (6 and 12 month) and male 150 mg/kg/day mice (12 month). Target organs included the liver, glandular stomach, forestomach (female rats) and kidney, mammary gland, and subcutaneous tissue (male rats). Liver neoplasms occurred in all dose groups of rats and mice and included hepatoadenoma, hepatocarcinoma, hepatocholangioma (rats only), hepatocholangiocarcinoma, and hepatoblastoma (mice only). Nonneoplastic liver lesions included eosinophilic and mixed cell foci (rats only), hypertrophy, oval cell hyperplasia, cystic degeneration (rats only), and bile duct hyperplasia. Mice also exhibited necrosis, hematopoietic cell proliferation, and hemosiderin pigmentation. Glandular stomach lesions in rats and mice included benign and malignant neuroendocrine tumors, neuroendocrine cell hyperplasia, and atrophy and in mice included glandular ectasia/chronic active inflammation. In female rats, the forestomach showed a positive trend in the incidences of squamous cell papilloma or carcinoma (combined). Male rats also exhibited kidney (renal tubule hyperplasia, nephropathy, and adenomacarcinoma), mammary gland (fibroadenoma), and subcutaneous tissue (fibroma, fibrosarcoma) lesions. Male rats also exhibited malignant mesotheliomas and splenic fibrosis. These data demonstrate that MEG is a multisite, multispecies carcinogen.

The Prince Edward Island Conceptual Model for Nursing: a nursing perspective of primary health care

The philosophy of primary health care (PHC) recognizes that health is a product of individual, social, economic, and political factors and that people have a right and a duty, individually and collectively, to participate in the course of their own health. The majority of nursing models cast the client in a dependent role and do not conceptualize health in a social, economic, and political context. The Prince Edward Island Conceptual Model for Nursing is congruent with the international move towards PHC. It guides the nurse in practising in the social and political environment in which nursing and health care take place. This model features a nurse/client partnership, the goal being to encourage clients to act on their own behalf. The conceptualization of the environment as the collective influence of the determinants of health gives both nurse and client a prominent position in the sociopolitical arena of health and health care.

Occupational coronary heart disease among bridge and tunnel officers

Traffic-control officers employed in New York City tunnels prior to 1981 have been at increased risk of mortality from coronary heart disease. In this study, the authors assessed current coronary heart disease prevalence and evaluated associations between coronary heart disease and occupational factors among New York City bridge and tunnel officers. A clinical cardiovascular disease surveillance and cross-sectional occupational epidemiologic study was conducted. The authors used comprehensive evaluations to identify current and prior incidences of coronary heart disease. Occupational risk factors evaluated included job strain, current and historic exposure to carbon monoxide, and occupational physical inactivity. Current carbon monoxide exposure was assessed via workshift changes in carboxyhemoglobin. Coronary heart disease occurred in 29 (5.5%) of the 526 bridge and tunnel officers examined. Risk of coronary heart disease was associated positively with total years each bridge and tunnel officer work had worked in that capacity (odds ratio = 1.64 for each decade of employment, adjusted for nonoccupational coronary heart disease risk factors). Carboxyhemoglobin levels were low in the subjects, and job strain and physical inactivity were very prevalent. Occupational factors contributed to the risk of coronary heart disease in New York City bridge and tunnel officers. The authors were unable to identify the specific factors that led to the increase in risk described.

Work-related death: a continuing epidemic

Worldwide, work-related illnesses and injuries kill approximately 1.1 million people per year. In 1992, an estimated 65,000 people in the United States died of occupational injuries or illness. Most estimates indicate that occupational diseases account for far more fatalities than occupational injuries. However, an accurate enumeration of occupational disease fatalities is hampered by a paucity of data, owing to underdiagnosis of occupational diseases and inadequacy of current surveillance systems. In this commentary, the authors review the epidemiology of death due to occupational disease and injury in the United States and discuss vulnerable populations, emerging trends, and prevention strategies for this ongoing public health problem.

Orenia salinaria sp. nov., a fermentative bacterium isolated from anaerobic sediments of Mediterranean salterns

A diverse range of fermentative bacteria have been isolated from the commercial salterns of Salin-de-Giraud (Camargue, France). One of these isolates, strain SG 3902T, has many of the morphological and physiological characteristics of the genus Orenia, as was confirmed by a phylogenetic study based on 16S rRNA gene sequencing. The closest species is Orenia marismortui, with a similarity of only 95.1%. However, strain SG 3902T, unlike O. marismortui, does not ferment mannose, glycogen or starch. The G + C contents of the DNA also differ significantly, being 29.6 mol% for O. marismortui and 33.7 mol% for strain SG 3902T. On the basis of these physiological and genetic differences, it is proposed that strain SG 3902T should be considered as a representative of a new species belonging to the genus Orenia, under the name Orenia salinaria sp. nov. The type strain is SG 3902T (= ATCC 700911).