Discordance between fat mass index and body mass index is associated with reduced bone mineral density in women but not in men: the Busselton Healthy Ageing Study

The obesity-BMD relationship is complex. In 3045 middle-aged adults, we found that in women (but not men) with discordant fat mass index (FMI)/BMI categories, higher body fat for BMI was associated with lower BMD, suggesting that increased fat mass without an accompanying increase in lean mass may be deleterious to bone.

INTRODUCTION

The relationship between obesity and BMD is complex. FMI (fat mass (kg) / height (m)²) is a more accurate measure of fatness than BMI, and depending on body composition, some individuals have discordant BMI/FMI categories. We examined associations between FMI, BMI and BMD in participants in the Busselton Healthy Ageing Study.

METHODS

Body composition and BMD of the hip, spine and total body were measured using DXA in 3045 participants (1644 females) aged 45-67 years. Using standard BMI/FMI categories, the participants were classified as underweight/fat deficit, normal, overweight/excess fat, obese I and obese II-III.

RESULTS

BMI and FMI categories were concordant in 77.3 % of females and 71.2 % of males. There were 12.9 % females and 13.2 % males in a higher FMI than BMI category (high body fat for BMI), whereas 9.8 % females and 15.6 % males were in a lower category (low body fat for BMI). Females with high body fat for BMI had significantly lower covariate-adjusted BMD at the femoral neck, total hip and total body (differences of 3.8, 5.1 and 2.6 %, respectively, all P < 0.05) than females with low body fat for BMI and lower total body BMD than women with concordant FMI/BMI (by 1.4 %, P = 0.04). In males, BMD did not differ significantly between those who were concordant or discordant for FMI/BMI categories.

CONCLUSION

In women (but not men) with discordant FMI/BMI categories, higher body fat for BMI was associated with lower BMD, suggesting that increased fat mass without an accompanying increase in lean mass may be deleterious to bone.

Hepatitis C-specific effector and regulatory CD4 T-cell responses are associated with the outcomes of primary infection

Clearance of primary hepatitis C virus (HCV) infection has been associated with strong and broadly targeted cellular immune responses. This study aimed to characterize HCV-specific CD4+ effector and regulatory T-cell numbers and cytokine production during primary infection. Antigen-specific CD4+ T-cell responses were investigated in a longitudinal cohort of subjects from pre-infection to postoutcome, including subjects who cleared [n=12] or became chronically infected [n=17]. A cross-sectional cohort with previously cleared, or chronic infection [n=15 for each], was also studied. Peripheral blood mononuclear cells were incubated with HCV antigens and surface stained for T-effector (CD4+CD25^high CD134+CD39-) and T-regulatory (CD4+CD25^high CD134+CD39+) markers, and culture supernatants assayed for cytokine production. Contrary to expectations, the breadth and magnitude of the HCV-specific CD4+ T-cell responses were higher in subjects who became chronically infected. Subjects who cleared the virus had HCV-specific CD4+ T-cell responses dominated by effector T cells and produced higher levels of IFN-γ, in contrast to HCV-specific CD4+ T-cell responses dominated by regulatory T cells and more IL-10 production in those who became chronically infected. Better understanding of the role of antigen-specific CD4+ T-cell responses in primary HCV will further define pathogenesis and help guide development of a preventative vaccine.

Gastro-oesophageal reflux and respiratory symptoms in Busselton adults: the effects of bodyweight and sleep apnoea

BACKGROUND/AIM

Respiratory symptoms and gastro-oesophageal reflux disease (GORD) are common within the general population. Although a number of epidemiological studies have addressed their relationship, none has investigated the confounding effects of body mass index (BMI) and obstructive sleep apnoea (OSA), both of which are associated with reflux.

METHODS

Men and women (2700) from the 2005-2007 cross-sectional Busselton health survey were included. Questionnaire data included demography, information on general health, asthma, cough, wheeze, dyspnoea and reflux symptoms (never, monthly or less often and weekly or more often). BMI, risk of OSA (Berlin questionnaire definition), spirometry and airway hyperresponsiveness (AHR) were recorded. The effects of BMI and OSA on the relationship between respiratory and reflux symptoms were examined using logistic regression models, expressed as adjusted odds ratios for risk of respiratory symptoms by reflux symptom category.

RESULTS

Fifty per cent had reflux symptoms (5-10% weekly or more often). Reflux symptoms had strong positive, dose-related associations with cough/phlegm, breathlessness, chest tightness and wheeze in the last 12 months (P < 0.001), but were not related to diagnosed asthma or AHR. Twenty-three per cent were at high risk of OSA and 63% had a BMI of >25 (22% > 30). Increased weight or high risk of OSA did not affect the relationship between respiratory symptoms and reflux symptoms.

CONCLUSION

The relationship between reflux and respiratory symptoms was independent of BMI, high risk of OSA or AHR. These findings suggest that reflux contributes directly to respiratory symptoms.

Non-cardiac chest pain: time to extend the rapid access chest pain clinic?

Non-cardiac chest pain is common. It has a low risk of coronary events, but causes considerable physical and social disability and inappropriate health-care usage. It is a heterogeneous condition, which may be caused by or associated with gastro-oesophageal, musculoskeletal or psychiatric abnormalities and sustained by psychological factors including catastrophisation, avoidance behaviour and abnormal help-seeking. These may coexist and their relative contributions may vary in different patients or at different times in an individual patient. The absence of a unitary cause probably explains why treatment studies show only moderate success. An individualised biopsychosocial approach takes account of all causative and sustaining processes and has been shown to work in pain syndromes at other sites. We suggest that this approach should be tried for chest pain using a multidisciplinary clinic model including cardiologists, psychologists and nurses linked with a Rapid Access Chest Pain Clinic.

Anti-eosinophil activity and clinical efficacy of the CRTH2 antagonist OC000459 in eosinophilic esophagitis

BACKGROUND

Eosinophilic esophagitis (EoE) is a chronic, Th2-type inflammatory disease. Chemoattractant receptor-homologous molecule on Th2 cells (CRTH2) is a prostaglandin D(2) (PGD(2)) receptor, expressed by Th2 cells and other inflammatory cells, including eosinophils and basophils, that mediates chemotaxis and activation. OC000459 is a selective CRTH2 antagonist and would be expected to suppress eosinophilic tissue inflammation. The purpose of this study was to evaluate the efficacy and safety of an OC000459 monotherapy in adult patients with active, corticosteroid-dependent or corticosteroid-refractory EoE.

METHODS

In this randomized, double-blind, placebo-controlled trial, 26 adult patients (m/f = 22/4; mean age 41 years, range 22-69 years) with active EoE, dependent or resistant to corticosteroids, were treated either with 100 mg OC000459 (n = 14) or placebo (n = 12) twice daily. Pre- and post-treatment disease activity was assessed clinically, endoscopically, histologically, and via biomarkers. The primary end point was the reduction in esophageal eosinophil infiltration.

RESULTS

After an 8-week OC000459 treatment, the esophageal eosinophil load decreased significantly, from 114.83 to 73.26 eosinophils per high-power field [(eos/hpf), P = 0.0256], whereas no reduction was observed with placebo (102.80-99.47 eos/hpf, P = 0.870). With OC000459, the physician's global assessment of disease activity improved from 7.13 to 5.18 (P = 0.035). OC000459 likewise reduced extracellular deposits of eosinophil peroxidase and tenascin C, the effects not seen with placebo. No serious adverse events were observed.

CONCLUSIONS

An 8-week treatment with the CRTH2-antagonist, OC000459, exerts modest, but significant, anti-eosinophil and beneficial clinical effects in adult patients with active, corticosteroid-dependent or corticosteroid-refractory EoE and is well tolerated.

How prepared is the retirement and residential aged care sector in Western Australia for older non-heterosexual people?

OBJECTIVE

To explore attitudes, knowledge and current practices of retirement and residential aged care providers in Western Australia towards accommodating older gay, lesbian, bisexual, transgender and intersex (GLBTI) individuals. GLBTI is used throughout as a general term to include people who are not exclusively heterosexual in identity, attraction and/or behaviour.

METHODS

Postal surveys were sent to 329 providers of accommodation to ask about their attitudes, knowledge and current practices towards older GLBTI people. Two focus groups were also held with managers of accommodation facilities and GLBTI community members.

RESULTS

Few respondents reported having experience with any older GLBTI residents in their retirement or residential aged care facility. There was poor inclusion of GLBTI issues in policy frameworks, and limited understanding regarding same-sex law reforms.

CONCLUSION

Older non-heterosexual people are often obscured within ageing population discourses, and conceal their identity for fear of discrimination. GLBTI-sensitive practices can help to facilitate the disclosure of sexual orientation and/or gender identity that may assist in meeting the unique needs of this group.

Patterns of airway disease and the clinical diagnosis of asthma in the Busselton population

The aim of this study was to examine how objective measures related to lung function cluster in the general population and how the patterns relate to asthma and bronchitis as diagnosed by a doctor (DDA and DDB, respectively). A cross-sectional survey of an age-stratified random general population sample of 1,969 adults from the electoral register of Busselton (Australia) was performed in 2005-2007. Respiratory symptoms, DDA ever, DDB ever, recent wheezing and smoking history, together with anthropometric measurements, forced expiratory volume in 1 s (FEV₁) and forced vital capacity (FVC), methacholine challenge or bronchodilator response, exhaled nitric oxide (eNO), skin-prick tests to common allergens, and blood eosinophil and neutrophil counts were studied. Cluster analysis (variables sex, age, atopy, FEV₁ % predicted, FEV₁/FVC, airway hyperresponsiveness, eNO, log eosinphil count, log neutrophil count and body mass index) was used to identify phenotypic patterns. Seven clusters (subjects with DDA and DDB, respectively) were identified: normal males (n=467; 7 and 13%), normal females (n=477; 12 and 18%), obese females (n=250; 16 and 28%), atopic younger adults (n=330; 21 and 17%), atopic adults with high eNO (n=130; 30 and 25%), atopic males with reduced FEV₁ (n=103; 33 and 32%) and atopic adults with bronchial hyperreactivity (n=212; 40 and 26%). The clinical diagnosis of asthma (ever) and bronchitis (ever) is not specific for any of the clustering patterns of airway abnormality.

Basolateral potassium (IKCa) channel inhibition prevents increased colonic permeability induced by chemical hypoxia

Major liver resection is associated with impaired intestinal perfusion and intestinal ischemia, resulting in decreased mucosal integrity, increased bacterial translocation, and an increased risk of postoperative sepsis. However, the mechanism by which ischemia impairs intestinal mucosal integrity is unclear. We therefore evaluated the role of Ca(2+)-sensitive, intermediate-conductance (IK(Ca)) basolateral potassium channels in enhanced intestinal permeability secondary to chemical hypoxia. The effects of chemical hypoxia induced by 100 μM dinitrophenol (DNP) and 5 mM deoxyglucose (DG) on basolateral IK(Ca) channel activity and whole cell conductance in intact human colonic crypts, and paracellular permeability (G(S)) in isolated colonic sheets, were determined by patch-clamp recording and transepithelial electrical measurements, respectively. DNP and DG rapidly stimulated IK(Ca) channels in cell-attached basolateral membrane patches and elicited a twofold increase (P = 0.004) in whole cell conductance in amphotericin B-permeabilized membrane patches, changes that were inhibited by the specific IK(Ca) channel blockers TRAM-34 (100 nM) and clotrimazole (CLT; 10 μM). In colonic sheets apically permeabilized with nystatin, DNP elicited a twofold increase (P = 0.005) in G(S), which was largely inhibited by the serosal addition of 50 μM CLT. We conclude that, in intestinal epithelia, chemical hypoxia increases G(S) through a mechanism involving basolateral IK(Ca) channel activation. Basolateral IK(Ca) channel inhibition may prevent or limit increased intestinal permeability during liver surgery.

Immunovirological correlates in human rabies treated with therapeutic coma

A 37-year-old woman was admitted to hospital and over the next 5 days developed a progressive encephalitis. Nuchal skin biopsy, analyzed using a Rabies TaqMan(c) PCR, demonstrated rabies virus RNA. She had a history in keeping with exposure to rabies whilst in South Africa, but had not received pre- or post-exposure prophylaxis. She was treated with a therapeutic coma according to the "Milwaukee protocol," which failed to prevent the death of the patient. Rabies virus was isolated from CSF and saliva, and rabies antibody was demonstrated in serum (from day 11 onwards) and cerebrospinal fluid (day 13 onwards). She died on day-35 of hospitalization. Autopsy specimens demonstrated the presence of rabies antigen, viral RNA, and viable rabies virus in the central nervous system.

Apical potassium (BK) channels and enhanced potassium secretion in human colon

The human colon has the capacity to secrete potassium (K(+)) ions and enhanced K(+) secretion is a feature of a variety of diarrhoeal diseases. Recent work points to K(+) secretion in human colon being mediated by high conductance (BK) K(+) channels located in the apical membrane of colonic epithelial cells. The aim of this review is to highlight the importance of these channels in maintaining K(+) homoeostasis in health and disease.

Plasma MIC-1 correlates with systemic inflammation but is not an independent determinant of nutritional status or survival in oesophago-gastric cancer

Background:

Macrophage inhibitory cytokine-1(MIC-1) is a potential modulator of systemic inflammation and nutritional depletion, both of which are adverse prognostic factors in oesophago-gastric cancer (OGC).

Methods:

Plasma MIC-1, systemic inflammation (defined as plasma C-reactive protein (CRP) of ⩾10 mg l^–1 or modified Glasgow prognostic score (mGPS) of ⩾1), and nutritional status were assessed in newly diagnosed OGC patients (n=293). Healthy volunteers (n=35) served as controls.

Results:

MIC-1 was elevated in patients (median=1371 pg ml^–1; range 141–39 053) when compared with controls (median=377 pg ml^–1; range 141–3786; P<0.001). Patients with gastric tumours (median=1592 pg ml^–1; range 141–12 643) showed higher MIC-1 concentrations than patients with junctional (median=1337 pg ml^–1; range 383–39 053) and oesophageal tumours (median=1180 pg ml^–1; range 258–31 184; P=0.015). Patients showed a median weight loss of 6.4% (range 0.0–33.4%), and 42% of patients had an mGPS of ⩾1 or plasma CRP of ⩾10 mg l^–1 (median=9 mg l^–1; range 1–200). MIC-1 correlated positively with disease stage (r²=0.217; P<0.001), age (r²=0.332; P<0.001), CRP (r²=0.314; P<0.001), and mGPS (r²=0.336; P<0.001), and negatively with Karnofsky Performance Score (r²=−0.269; P<0.001). However, although MIC-1 correlated weakly with dietary intake (r²=0.157; P=0.031), it did not correlate with weight loss, BMI, or anthropometry. Patients with MIC-1 levels in the upper quartile showed reduced survival (median=204 days; 95% CI 157–251) when compared with patients with MIC-1 levels in the lower three quartiles (median=316 days; 95% CI 259–373; P=0.036), but MIC-1 was not an independent prognostic indicator.

Conclusions:

There is no independent link between plasma MIC-1 levels and depleted nutritional status or survival in OGC.

Changes in the prevalence of asthma in adults since 1966: the Busselton health study

Asthma prevalence has increased worldwide; although less so in developed countries recently. This study assessed changes in the prevalence of asthma and related symptoms in the Busselton community since 1966. Cross-sectional respiratory health surveys of Busselton adults were conducted in 1966, 1969, 1972, 1975, 1981, 1990 and 2005-2007. Logistic regression models were used to estimate prevalence rates of asthma, respiratory symptoms, smoking, airway hyperresponsiveness (AHR) and atopy and to make comparisons in 2005-2007 and previous survey years. Asthma was defined as ever having doctor-diagnosed asthma (DDA). The prevalence of DDA was around 6% from 1966 to 1975, 8% in 1981 and rose to 19% in 2005-2007. From 1981 to 2005-2007, smoking prevalence declined and obesity and atopy increased but changes in these variables explained only a small part of the increase in DDA. Wheeze and cough/phlegm increased but AHR, breathlessness and doctor-diagnosed bronchitis remained relatively stable over the same period. These observations indicate that the increase in DDA is partly explained by increased symptoms and atopy. The lack of changes in AHR and doctor-diagnosed bronchitis suggests that factors such as diagnostic transfer and increased awareness of asthma have also contributed to the rise in prevalence of DDA.

One hundred questions of importance to the conservation of global biological diversity

We identified 100 scientific questions that, if answered, would have the greatest impact on conservation practice and policy. Representatives from 21 international organizations, regional sections and working groups of the Society for Conservation Biology, and 12 academics, from all continents except Antarctica, compiled 2291 questions of relevance to conservation of biological diversity worldwide. The questions were gathered from 761 individuals through workshops, email requests, and discussions. Voting by email to short-list questions, followed by a 2-day workshop, was used to derive the final list of 100 questions. Most of the final questions were derived through a process of modification and combination as the workshop progressed. The questions are divided into 12 sections: ecosystem functions and services, climate change, technological change, protected areas, ecosystem management and restoration, terrestrial ecosystems, marine ecosystems, freshwater ecosystems, species management, organizational systems and processes, societal context and change, and impacts of conservation interventions. We anticipate that these questions will help identify new directions for researchers and assist funders in directing funds.