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1.
Epidemics ; 44: 100687, 2023 09.
Article in English | MEDLINE | ID: mdl-37348379

ABSTRACT

Plasmodium falciparum and P. vivax are the two most common causes of malaria. While the majority of deaths and severe morbidity are due to P. falciparum, P. vivax poses a greater challenge to eliminating malaria outside of Africa due to its ability to form latent liver stage parasites (hypnozoites), which can cause relapsing episodes within an individual patient. In areas where P. falciparum and P. vivax are co-endemic, individuals can carry parasites of both species simultaneously. These mixed infections complicate dynamics in several ways: treatment of mixed infections will simultaneously affect both species, P. falciparum can mask the detection of P. vivax, and it has been hypothesised that clearing P. falciparum may trigger a relapse of dormant P. vivax. When mixed infections are treated for only blood-stage parasites, patients are at risk of relapse infections due to P. vivax hypnozoites. We present a stochastic mathematical model that captures interactions between P. falciparum and P. vivax, and incorporates both standard schizonticidal treatment (which targets blood-stage parasites) and radical cure treatment (which additionally targets liver-stage parasites). We apply this model via a hypothetical simulation study to assess the implications of different treatment coverages of radical cure for mixed and P. vivax infections and a "unified radical cure" treatment strategy where P. falciparum, P. vivax, and mixed infections all receive radical cure after screening glucose-6-phosphate dehydrogenase (G6PD) normal. In addition, we investigated the impact of mass drug administration (MDA) of blood-stage treatment. We find that a unified radical cure strategy leads to a substantially lower incidence of malaria cases and deaths overall. MDA with schizonticidal treatment was found to decrease P. falciparum with little effect on P. vivax. We perform a univariate sensitivity analysis to highlight important model parameters.


Subject(s)
Coinfection , Malaria, Falciparum , Malaria, Vivax , Malaria , Humans , Plasmodium vivax , Malaria/drug therapy , Malaria/epidemiology , Malaria/parasitology , Malaria, Vivax/drug therapy , Malaria, Vivax/epidemiology , Malaria, Vivax/parasitology , Malaria, Falciparum/drug therapy , Malaria, Falciparum/epidemiology , Malaria, Falciparum/parasitology , Recurrence
3.
Water Resour Res ; 56(7): e2019WR026475, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32999509

ABSTRACT

The water surface expression of liftoff and its dependence on discharge are examined using numerical simulations with the Regional Ocean Modeling System (ROMS). Liftoff is the process by which buoyant river water separates from the bed and flows over denser saltwater. During low-discharge conditions liftoff occurs in the river and is accompanied by a change in the surface slope. During high-discharge conditions liftoff occurs outside the mouth and generates a ridge on the water surface. The location and height of the ridge can be described by analytical equations in terms of discharge, shelf slope, and river mouth aspect ratio. The offshore distance and height of the ridge are proportional to the river discharge and vary inversely with river mouth aspect ratio. For steep shelf slopes liftoff occurs close to the river mouth and generates a large ridge. The ridge is modified, but not eliminated, by the presence of tides. The water surface slope change at the ridge peak is large enough to be detected by the upcoming Surface Water and Ocean Topography (SWOT) altimeter and can be used to identify the liftoff location during high discharge. However, during low discharge the water surface slope change at the liftoff location is too small to be detected by SWOT. These results indicate that remote measurements of the presence or absence of the ridge may be useful to distinguish between low and high flows, and remote measurements of the ridge location or height could be used to estimate freshwater discharge.

4.
J Hum Nutr Diet ; 2020 Jan 07.
Article in English | MEDLINE | ID: mdl-31912581

ABSTRACT

BACKGROUND: To explore the barriers and enablers experienced by nutrition and dietetic professionals in the implementation of the standardised Nutrition Care Process (NCP) across 10 different countries. NCP related beliefs, motivations and values were investigated and compared. METHODS: A validated online survey was disseminated to nutrition and dietetics professionals in 10 countries in the local language during 2017. Cross-sectional associations and differences between countries were explored for level of implementation, barriers/enablers and attitudes/motivation among the respondents. RESULTS: Higher NCP implementation was associated with greater occurrence of enabling aspects, as well as fewer occurrences of barriers. The most common enabler was 'recommendation by the national dietetic association' (69%) and the most common barrier was 'lack of time' (39%). A longer experience of NCP use was associated with a more positive attitude towards all NCP aspects. Differences between countries were identified, regarding both the occurrence of barriers/enablers and attitudes/motivations. CONCLUSIONS: Implementation efforts need to be tailored to country-specific contexts when implementing a new standard of care framework among nutrition and dietetic professionals. Additional research is needed to further assess the management and workplace strategies to support the development of nutrition and dietetics professionals in multidisciplinary healthcare organisations.

5.
Ann R Coll Surg Engl ; 100(4): 308-315, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29364006

ABSTRACT

Introduction The association between the neutrophil-lymphocyte ratio (NLR) and outcome in elective colorectal cancer surgery is well established; the relationship between NLR and the emergency colorectal cancer patient is, as yet, unexplored. This paper evaluates the predictive quality of the NLR for outcome in the emergency colorectal cancer patient. Materials and Methods A total of 187 consecutive patients who underwent emergency surgery for colorectal cancer were included in the study. NLR was calculated from the haematological tests done on admission. Receiver operating characteristic analyses were used to determine the most suitable cut-off for NLR. Outcomes were assessed by mortality at 30 and 90 days using stepwise Cox proportional hazards regression. Results An NLR cut-off of 5 was found to have the highest sensitivity and specificity. At 30 days, age and time from admission to surgery were associated with increased mortality; a high NLR was associated with an increased risk of mortality in univariate but not multivariate analysis. At 90 days, age, NLR, time from admission to surgery and nodal status were all significantly associated with increased mortality on multivariate analysis. Conclusions Pre-operative NLR is a cheap, easily performed and useful clinical tool to aid prediction of outcome in the emergency colorectal cancer patient.


Subject(s)
Colorectal Neoplasms/blood , Digestive System Surgical Procedures/statistics & numerical data , Emergency Treatment/statistics & numerical data , Lymphocytes , Neutrophils , Patient Selection , Age Factors , Aged , Aged, 80 and over , Colorectal Neoplasms/mortality , Colorectal Neoplasms/pathology , Colorectal Neoplasms/surgery , Digestive System Surgical Procedures/adverse effects , Digestive System Surgical Procedures/methods , Emergency Treatment/methods , Female , Humans , Leukocyte Count , Lymphatic Metastasis , Male , Multivariate Analysis , Postoperative Period , Predictive Value of Tests , Preoperative Period , Prognosis , ROC Curve , Retrospective Studies , Survival Analysis , Time Factors , Treatment Outcome
6.
J Nutr Health Aging ; 20(1): 8-15, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26728927

ABSTRACT

OBJECTIVES: Evaluate a 4-week dementia specific nutrition education intervention to determine long term knowledge and healthy dietary behaviour changes in 72 elderly men and women. DESIGN: A mixed method design used qualitative findings to triangulate quantitative within-subject changes to determine efficacy and sustained dietary behaviour change. SETTING: Community. PARTICIPANTS: 72 independently-living individuals. INTERVENTION: 4-week dementia specific nutrition education intervention. MEASUREMENTS: Change in participant attitude, confidence, dietary patterns, cooking behaviour, and knowledge were analysed within-subjects using non-parametric repeated-measures procedures. Significance level was set at 5% (α = 0.05). Effect size (ES) was reported and identified as small (S), medium (M) or large (L) if a significant change was observed. RESULTS: Compared to before the nutrition education intervention participants had an increase in total knowledge (p < 0.001, ES = 0.972 (L)), consumed a greater variety of vegetables (p = 0.007, ES = 0.35 (M)), used less salt (p = 0.006, ES = -0.42 (M-L)) and increased spice use (p < 0.001, ES = 0.40 (M-L)). Participants overcame barriers to enable sustained change, held a positive view on healthy living and believed government should invest in this sector of the community. Sharing and socialisation emerged as important themes that increased program satisfaction. CONCLUSION: The dementia specific nutrition program produced a large effect in knowledge improvement from pre to post, which was retained at follow up, consolidated observational and participatory learning which produced a moderate increase in healthy dietary behaviours which participants valued and sustained.


Subject(s)
Dementia , Diet , Feeding Behavior , Health Education/standards , Health Knowledge, Attitudes, Practice , Health Services for the Aged/standards , Aged , Cooking , Dementia/prevention & control , Female , Health Education/methods , Humans , Male , Nutritional Status , Personal Satisfaction , Residence Characteristics , Sodium Chloride, Dietary , Vegetables
7.
Int J Hyg Environ Health ; 218(5): 444-51, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25857756

ABSTRACT

Environmental exposure to metals has been linked to adverse health outcomes. Exposure to cadmium has been associated with decreased bone density, an increased risk of osteoporotic fracture and possible renal dysfunction. Older women are a group at risk of renal and bone density impacts and exposure to metals may be an important risk factor for these health outcomes. This study was a cross sectional study of 77 women aged 50 years and above examining the relationship between metals exposure and renal and bone health. Urinary and blood metals concentrations, plasma creatinine, iron, ferritin and transferrin were measured in these subjects. Bone biomarkers assessed included the pyridinium crosslinks, pyridinoline and deoxypyridinoline measured by ELISA. Renal function was assessed using eGFR and KIM-1. Whole body, hip and lumbar spine bone mineral density was assessed using DEXA. Blood and urinary metals concentrations were generally low in the subjects, with a median urinary cadmium concentration of 0.26 µg/g creatinine (range <0.065-1.03 µg/g). Urinary cadmium was found to be a significant predictor of bone mineral density at whole body, lumber spine, total hip and femoral neck, with increasing urinary Cd concentrations associated with decreased bone density. Urinary cadmium and aluminium concentrations were positively correlated with bone resorption whilst blood zinc and mercury concentrations were negatively correlated. Urinary aluminium was positively correlated with KIM-1 concentrations, a marker of early kidney damage, however blood zinc concentrations were significantly negatively correlated with this biomarker. This study provides additional support for low cadmium exposure being of concern for the health of older women. Further investigation into the role of exposure to other metals on bone and renal health is warranted.


Subject(s)
Bone Density/drug effects , Bone Resorption/etiology , Cadmium/adverse effects , Environmental Exposure/adverse effects , Kidney/drug effects , Metals/adverse effects , Aged , Aged, 80 and over , Aluminum/blood , Aluminum/urine , Biomarkers/blood , Biomarkers/urine , Cadmium/blood , Cadmium/urine , Creatinine/blood , Cross-Sectional Studies , Female , Glomerular Filtration Rate/drug effects , Hepatitis A Virus Cellular Receptor 1 , Humans , Kidney/metabolism , Kidney/physiopathology , Kidney Function Tests , Membrane Glycoproteins/blood , Mercury/blood , Metals/blood , Metals/urine , Middle Aged , Receptors, Virus/blood , Zinc/blood
8.
Nutr Metab Cardiovasc Dis ; 25(4): 388-95, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25638597

ABSTRACT

BACKGROUND AND AIMS: Protein consumption has been associated with cardio-metabolic benefits, including weight loss and improved insulin sensitivity, and may have potential benefits for individuals with fatty liver disease (FLD). We investigated the effect of increasing dietary protein intake from whey relative to carbohydrate on hepatic steatosis. METHODS AND RESULTS: A two-year randomized, double-blind, placebo-controlled trial of 30 g/day whey protein-supplemented beverage (protein) or an energy-matched low-protein high-carbohydrate beverage (control) for cardio-metabolic and bone health in 219 healthy elderly women, recruited from the Western Australian general population. Hepatic steatosis was quantified using computed tomographic liver-to-spleen (L/S) ratio. FLD was defined as liver-to-spleen difference <10 Hounsfield units. At baseline, FLD prevalence was 11.4%. Control and protein groups were similar in body mass index (BMI), insulin resistance, L/S ratio and FLD prevalence at baseline. At two-years, dietary protein increased by 20 g in the protein, but not the control, group. Total energy intake and physical activity remained similar between groups. At two-years, BMI and FLD prevalence increased in both groups, with no between group differences. L/S ratio increased in control, but not protein, group at two-years, with no between group differences. In a within group comparison, change in BMI correlated with changes in L/S ratio in control (r = 0.37, P = 0.0007), but not with protein group (r = 0.04, P = 0.73). CONCLUSION: Increasing dietary protein intake from whey relative to carbohydrate does not reduce weight, hepatic steatosis or the prevalence of FLD in elderly women. However, it may prevent worsening of hepatic steatosis associated with weight gain. CLINICAL TRIALS REGISTRATION: Australian New Zealand Clinical Trials Registry (Registration no. ACTRN012607000163404).


Subject(s)
Diet , Fatty Liver/prevention & control , Weight Gain , Whey Proteins/administration & dosage , Aged , Aged, 80 and over , Blood Glucose/metabolism , Body Mass Index , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Double-Blind Method , Energy Intake , Female , Humans , Insulin/blood , Insulin Resistance , Motor Activity , New Zealand , Triglycerides/blood , Waist Circumference
9.
J Hum Nutr Diet ; 28(5): 452-64, 2015 Oct.
Article in English | MEDLINE | ID: mdl-25157608

ABSTRACT

BACKGROUND: Dairy intake is likely to influence dietary energy density (ED) and nutrient density (ND), which are factors representing aspects of dietary quality. Although evidence suggests dairy intake is unlikely to contribute to obesity, intake tends to decrease over adolescence, potentially as a result of concerns around weight gain. We examined associations between dairy intake, ED and ND, and investigated relationships with obesity in adolescents. METHODS: The present study comprised a cross-sectional study of 1613 14-year-olds in the Western Australian Pregnancy Cohort (Raine) Study. Adolescents completed a 212-item food frequency questionnaire. Nutrient Rich Food index 9.3 (NRF9.3) was used to estimate ND. Age-specific body mass index (BMI) and waist-height cut-offs were used to categorise obesity risk. RESULTS: Mean (SD) dairy intake was: 2.62 (1.51) servings daily; ED was 4.53 (0.83) (food and beverage) and 6.28 (1.33) (food only); ND was 373 (109). Dairy intake was inversely associated with ED and positively associated with ND. The odds of being overweight (as assessed by BMI) increased by 1.24 (95% confidence interval = 1.09-1.42) with each 100-point increase in ND, after adjustment for potential confounders and energy intake. ED measures and dairy intake were inversely associated with obesity after adjustment for confounders; associations became nonsignificant after energy adjustment. CONCLUSIONS: The NRF9.3 was originally designed to assess foods, not diets. Further research in other cohorts to determine whether similar findings exist, or investigations into alternate measures of dietary ND, may prove useful. Our findings may be the result of factors such as an excess consumption of refined but fortified foods. Although higher dairy intakes were associated with higher ND, intakes were not associated with higher obesity risk.


Subject(s)
Body Mass Index , Dairy Products , Energy Intake , Feeding Behavior , Obesity/etiology , Adolescent , Australia , Cross-Sectional Studies , Diet , Female , Humans , Male , Weight Gain
10.
Health Technol Assess ; 17(18): 1-281, 2013 May.
Article in English | MEDLINE | ID: mdl-23632142

ABSTRACT

BACKGROUND: Many older people living in care homes (long term residential care or nursing homes) are depressed. Exercise is a promising non-drug intervention for preventing and treating depression in this population. OBJECTIVE: To evaluate the impact of a 'whole-home' intervention, consisting of training for residential and nursing home staff backed up with a twice-weekly, physiotherapist-led exercise class on depressive symptoms in care home residents. DESIGN: A cluster randomised controlled trial with a cost-effectiveness analysis to compare (1) the prevalence of depression in intervention homes with that in control homes in all residents contributing data 12 months after homes were randomised (cross-sectional analysis); (2) the number of depressive symptoms at 6 months between intervention and control homes in residents who were depressed at pre-randomisation baseline assessment (depressed cohort comparison); and (3) the number of depressive symptoms at 12 months between intervention and control homes in all residents who were present at pre-randomisation baseline assessment (cohort comparison). SETTING: Seventy-eight care homes in Coventry and Warwickshire and north-east London. PARTICIPANTS: Care home residents aged ≥ 65 years. INTERVENTIONS: Control intervention: Depression awareness training programme for care home staff. Active intervention: A 'whole-home' exercise intervention, consisting of training for care home staff backed up with a twice-weekly, physiotherapist-led exercise group. MAIN OUTCOME MEASURES: Geriatric Depression Scale-15, proxy European Quality of Life-5 Dimensions (EQ-5D), cost-effectiveness from an National Health Service perspective, peripheral fractures and death. RESULTS: We recruited a total of 1054 participants. Cross-sectional analysis: We obtained 595 Geriatric Depression Scale-15 scores and 724 proxy EQ-5D scores. For the cohort analyses we obtained 765 baseline Geriatric Depression Scale-15 scores and 776 proxy EQ-5D scores. Of the 781 who we assessed prior to randomisation, 765 provided a Geriatric Depression Scale-15 score. Of these 374 (49%) were depressed and constitute our depressed cohort. Resource-use and quality-adjusted life-year data, based on proxy EQ-5D, were available for 798 residents recruited prior to randomisation. We delivered 3191 group exercise sessions with 31,705 person attendances and an average group size of 10 (5.3 study participants and 4.6 non-study participants). On average, our participants attended around half of the possible sessions. No serious adverse events occurred during the group exercise sessions. In the cross-sectional analysis the odds for being depressed were 0.76 [95% confidence interval (CI) 0.53 to 1.09] lower in the intervention group at 12 months. The point estimates for benefit for both the cohort analysis (0.13, 95% CI -0.33 to 0.60) and depressed cohort (0.22, 95% CI -0.52 to 0.95) favoured the control intervention. There was no evidence of differences in fracture rates or mortality (odds ratio 1.07, 95% CI 0.79 to 1.48) between the two groups. There was no evidence of differences in the other outcomes between the two groups. Economic analysis: The additional National Health Service cost of the OPERA intervention was £374 per participant (95% CI -£655 to £1404); the mean difference in quality-adjusted life-year was -0.0014 (95% CI -0.0728 to 0.0699). The active intervention was thus dominated by the control intervention, which was more effective and less costly. CONCLUSION: The results do not support the use of a whole-home physical activity and moderate-intensity exercise programme to reduce depression in care home residents. TRIAL REGISTRATION: Current Controlled Trials ISRCTN43769277. FUNDING: This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 17, No. 18. See the Health Technology Assessment programme website for further project information.


Subject(s)
Depression/therapy , Exercise Therapy/economics , Exercise Therapy/methods , Homes for the Aged/statistics & numerical data , Nursing Homes/statistics & numerical data , Activities of Daily Living , Age Factors , Aged , Aged, 80 and over , Cognition , Cost-Benefit Analysis , Cross-Sectional Studies , Female , Fractures, Bone/epidemiology , Geriatric Assessment/methods , Humans , Interpersonal Relations , Male , Mobility Limitation , Mortality , Pain/epidemiology , Prescription Drugs , Quality of Life , Sex Factors
11.
J Nutr Health Aging ; 17(2): 112-8, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23364487

ABSTRACT

OBJECTIVES: Identify the extent of under-reporting of energy intake and the characteristics associated with implausible intakes in elderly women. DESIGN: Dietary intake was assessed using a 3-day weighed food record. Protein intake was validated by 24-hour urinary nitrogen. To examine under-reporting, participants were grouped according to their energy intake and compared to the Goldberg cut-off equation. Logistic regression was performed to assess the influence of body mass index (BMI) and social-demographic factors on under-reporting. SETTING: Community dwelling elderly women from Perth, Western Australia. PARTICIPANTS: 217 elderly women aged 70-80 years. RESULTS: Under-reporters had a higher physical activity level (p<0.001) compared with acceptable-reporters. The under-reporters also had a higher body weight (p=0.006), body mass index (BMI) (p=0.001), waist (p=0.011), hip circumference (p<0.001), whole body fat mass (p<0.001) and percentage body fat (p<0.001) than acceptable-reporters. Under-reporters had a significantly lower intakes of protein, fat, carbohydrate and alcohol (p<0.001) and fewer reported food items, compared with acceptable reporters. However, 24-hour urinary nitrogen was only marginally different between the two groups (p=0.053). Participants with a higher BMI were more likely to under-report their energy intake (BMI=25-29.9: odds ratio=2.98[95% CI=1.46-6.09]; BMI≥30: 5.84[2.41-14.14]). CONCLUSION: Under-reporting energy intake in elderly women was associated with a higher BMI, body fat and higher self-reported physical activity levels. A higher BMI (≥25) appears to be most significant factor in determining if elderly women will underreport their food intake and may be related to body image. These results have implications for undertaking surveys of food intake in elderly women.


Subject(s)
Body Composition , Body Mass Index , Diet , Energy Intake , Obesity , Self Disclosure , Self Report , Adipose Tissue , Aged , Aged, 80 and over , Alcohol Drinking , Body Weight , Diet Records , Dietary Proteins/urine , Exercise , Female , Hip , Humans , Logistic Models , Nitrogen/urine , Waist Circumference
12.
J Nutr Health Aging ; 14(9): 723-9, 2010 Nov.
Article in English | MEDLINE | ID: mdl-21085900

ABSTRACT

OBJECTIVE: As women age total dietary intake falls which may increase the risk of dietary deficiencies in some individuals. The aims of this study were to investigate the changes in nutrient and dietary intakes that occurred with aging in a seven-year longitudinal study of elderly Australian women and to evaluate the adequacy of their dietary intakes. DESIGN: Longitudinal population based study on health with ageing. PARTICIPANTS AND SETTING: 911 free-living elderly women aged 70-85 years at baseline from a cohort of 1500 elderly women. MEASUREMENTS: At baseline, 60 and 84 months, self-reported Food Frequency Questionnaires (FFQ) and demographics were collected and anthropometry measured. RESULTS: During the 84 month subjects lost height (1.8 cm) and body weight (1.9 kg). Intakes of energy and macronutrients carbohydrate, fat and protein declined significantly over the 84 months. Mean energy derived from saturated fat was above, whereas energy derived from carbohydrate was below, recommended levels of intake at all time points. Intakes of vitamins and minerals all declined with age and subjects had suboptimal intakes of folate, vitamin E and calcium at all time points. The serve sizes for potato and meat and the consumption of milk, bread and variety of vegetables declined significantly over time reflecting changes in nutrient intake. CONCLUSIONS: Ageing is associated with reduced food intake resulting in inadequate intakes in energy, and some nutrients. Nutrition policy for elderly women should include advice to maintain or increase intakes of carbohydrate, milk, vegetables and fruit whilst continuing to reduce fat intake.


Subject(s)
Diet , Energy Intake , Geriatric Assessment/methods , Malnutrition , Aged , Aged, 80 and over , Australia , Body Height , Body Weight , Diet Surveys , Female , Humans , Longitudinal Studies , Nutrition Policy , Surveys and Questionnaires
13.
J Dairy Sci ; 92(9): 4467-80, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19700708

ABSTRACT

Ionophores and supplemental fat are fed to lactating cows to improve feed efficiency. Their effect on rumen fermentation is similar, but less is known about their impact on rumen microbes. The objective of this study was to determine the effects of monensin (M), bacitracin (B), and soybean oil (O) on microbial populations. Mixed cultures of rumen microbes were incubated in 5 dual-flow continuous fermentors and fed 13.8 g of alfalfa hay pellets daily (DM basis) for 16 d. All fermentors were allowed to stabilize for 4 d. From d 5 to 10, two fermentors received O (5% of diet DM), one fermentor received M (22 mg/kg), and one received B (22 mg/kg). From d 11 to 16, the 2 fermentors receiving O also received either M (OM) or B (OB) and O was included in the fermentors receiving M (MO) and B (BO). One fermentor served as the control and received 100% alfalfa pellets throughout the experiment. Each run was replicated 3 times. Samples were taken at 2 h after the morning feeding on d 4, 10, and 16 and were analyzed for bacterial populations using terminal restriction fragment length polymorphism. Volatile fatty acid concentration, methane production, and pH in the control cultures were not affected by time and remained similar during the entire experiment. The M and O treatments reduced molar concentration of acetate, increased concentration of propionate, and decreased methane production. Bacitracin did not alter acetate or propionate concentration, but reduced methane production. All 3 treatments (M, B, and O) altered the fragment patterns of microbial profiles. In contrast, treatments MO, OM, BO, and OB had little effect on culture fermentation despite differences in the patterns of microbial fragments. The terminal restriction fragment length polymorphism data suggest that microbial adaptation to the in vitro system in the control fermentor occurred within 4 d.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Fermentation/drug effects , Rumen/microbiology , Soybean Oil/pharmacology , Ammonia/metabolism , Animals , Bacteria/classification , Biodiversity , Bioreactors , Cattle , Fatty Acids, Volatile/metabolism , Female , Hydrogen-Ion Concentration , In Vitro Techniques , Methane/metabolism
14.
Osteoporos Int ; 20(2): 335-40, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18575949

ABSTRACT

UNLABELLED: Few studies have investigated the long-term effects of potassium intake on BMD. In a cohort of 266 elderly women, we found that baseline potassium intake as reflected by 24-hour urine potassium excretion had positive association with BMD measured at 1 and/or 5 years later, suggesting a role of dietary potassium on osteoporosis prevention. INTRODUCTION: High dietary potassium intake has been suggested to be beneficial for bone structure, but few studies have investigated the long-term effects of potassium intake on BMD in elderly women. We examined the relationship between potassium intake as reflected by 24-hour urine potassium excretion and bone density in a cohort of elderly women. METHODS: The study subjects were 266 elderly postmenopausal women aged 70-80 years. Twenty-four-hour urinary potassium excretion was determined at baseline. At one year hip DXA BMD was measured, at 5 years hip and total body DXA BMD and distal radius and tibia pQCT vBMD were measured. The effects of potassium were evaluated by ANCOVA according to the quartile of baseline urinary potassium excretion. RESULTS: After adjustment for confounding factors, subjects in the highest quartile of urinary potassium excretion had significantly higher total hip BMD at 1 (5%) and 5 years (6%), and significantly higher total body BMD (4%) and 4% distal tibia total (7%) and trabecular vBMD (11%) at 5 years than those in the lowest quartile. CONCLUSIONS: Potassium intake shows positive association with bone density in elderly women, suggesting that increasing consumption of food rich in potassium may play a role in osteoporosis prevention.


Subject(s)
Postmenopause/metabolism , Potassium, Dietary/administration & dosage , Absorptiometry, Photon , Aged , Aged, 80 and over , Analysis of Variance , Biomarkers/urine , Bone Density/drug effects , Female , Humans , Potassium/urine , Prospective Studies , Radius/diagnostic imaging , Tibia/diagnostic imaging , Tibia/physiology , Tomography, X-Ray Computed
15.
Osteoporos Int ; 20(7): 1183-91, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19037576

ABSTRACT

SUMMARY: Few studies have evaluated the effects of homocysteine and methylenetetrahydrofolate reductase (MTHFR) genotype on age-related bone loss. In our 5-year cohort study with 1,213 women aged 70-85 years, high homocysteine is associated with greater hip bone loss but not fracture risk. The effect of MTHFR genotype on bone density and fracture is weak. INTRODUCTION: Previous studies on the effects of homocysteine and MTHFR genotype on bone mineral density (BMD) and osteoporotic fracture risk have shown inconsistent results. Few studies have evaluated their effects on age-related bone loss. We evaluated the effects of homocysteine and MTHFR genotype variation on hip BMD and fracture risk over 5 years in a cohort of 1,213 community-dwelling women aged 70-85 years. METHODS: Nutritional intake and prevalent fracture status were assessed at baseline, plasma homocysteine was measured at year 1, and hip dual-energy X-ray absorptiometry (DXA) BMD was measured at years 1 and 5. Clinical incident osteoporotic fractures confirmed by radiographic report were collected throughout the study and the MTHFR gene C677T and A1298C polymorphisms genotyped. Data were analyzed using analysis of covariance and Cox proportional hazard regression. RESULTS: The highest tertile of homocysteine was associated with a greater hip BMD loss over 4 years (-2.8%) compared to the middle (-1.6%) and lowest tertiles (-1.2%) (P < 0.001). This effect remained after adjustment for covariates. There was no effect of homocysteine on fracture prevalence or incidence. MTHFR gene variation was only weakly related to one of the bone outcome measures. CONCLUSION: In this study population, high homocysteine is associated with greater hip bone loss but not fracture risk.


Subject(s)
Fractures, Bone , Homocysteine/blood , Methylenetetrahydrofolate Reductase (NADPH2)/genetics , Osteoporosis, Postmenopausal , Polymorphism, Single Nucleotide , Absorptiometry, Photon , Aged , Aged, 80 and over , Bone Density , Female , Fractures, Bone/blood , Fractures, Bone/genetics , Hip Joint/diagnostic imaging , Humans , Osteoporosis, Postmenopausal/blood , Osteoporosis, Postmenopausal/genetics , Prospective Studies , Western Australia
16.
Osteoporos Int ; 19(7): 961-8, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18038243

ABSTRACT

UNLABELLED: The 1p36 region of the human genome has been identified as containing a QTL for BMD in multiple studies. We analysed the TNFRSF1B gene from this region, which encodes the TNF receptor 2, in two large population-based cohorts. Our results suggest that variation in TNFRSF1B is associated with BMD. INTRODUCTION: The TNFRSF1B gene, encoding the TNF receptor 2, is a strong positional and functional candidate gene for impaired bone structure through the role that TNF has in bone cells. The aims of this study were to evaluate the role of variations in the TNFRSF1B gene on bone structure and osteoporotic fracture risk in postmenopausal women. METHODS: Six SNPs in TNFRSF1B were analysed in a cohort of 1,190 postmenopausal Australian women, three of which were also genotyped in an independent cohort of 811 UK postmenopausal women. Differences in phenotypic means for genotype groups were examined using one-way ANOVA and ANCOVA. RESULTS: Significant associations were seen for IVS1+5580A>G with BMD and QUS parameters in the Australian population (P = 0.008 - 0.034) and with hip BMD parameters in the UK population (P = 0.005 - 0.029). Significant associations were also observed between IVS1+6528G>A and hip BMD parameters in the UK cohort (P = 0.0002 - 0.003). We then combined the data from the two cohorts and observed significant associations between both IVS1+5580A>G and IVS1+6528G>A and hip BMD parameters (P = 0.002 - 0.033). CONCLUSIONS: Genetic variation in TNFRSF1B plays a role in the determination of bone structure in Caucasian postmenopausal women, possibly through effects on osteoblast and osteoclast differentiation.


Subject(s)
Bone Density/genetics , Fractures, Bone/genetics , Osteoporosis, Postmenopausal/genetics , Polymorphism, Single Nucleotide , Receptors, Tumor Necrosis Factor, Type II/genetics , Aged , Aged, 80 and over , Amino Acids/blood , Australia/epidemiology , Cohort Studies , Female , Fractures, Bone/epidemiology , Genotype , Humans , Middle Aged , Osteocalcin/blood , Osteoporosis, Postmenopausal/blood , Osteoporosis, Postmenopausal/urine , Prevalence , United Kingdom/epidemiology
17.
Ann Rheum Dis ; 67(6): 841-8, 2008 Jun.
Article in English | MEDLINE | ID: mdl-17875549

ABSTRACT

OBJECTIVE: To determine the clinical effect of dietary supplementation with low-dose omega-3-polyunsaturated fatty acids on disease activity and endothelial function in patients with systemic lupus erythematosus. METHODS: A 24-week randomised double-blind placebo-controlled parallel trial of the effect of 3 g of omega-3-polyunsaturated fatty acids on 60 patients with systemic lupus erythematosus was performed. Serial measurements of disease activity using the revised Systemic Lupus Activity Measure (SLAM-R) and British Isles Lupus Assessment Group index of disease activity for systemic lupus erythematosus (BILAG), endothelial function using flow-mediated dilation (FMD) of the brachial artery, oxidative stress using platelet 8-isoprostanes and analysis of platelet membrane fatty acids were taken at baseline, 12 and 24 weeks. RESULTS: In the fish oil group there was a significant improvement at 24 weeks in SLAM-R (from 9.4 (SD 3.0) to 6.3 (2.5), p<0.001); in BILAG (from 13.6 (6.0) to 6.7 (3.8), p<0.001); in FMD (from 3.0% (-0.5 to 8.2) to 8.9% (1.3 to 16.9), p<0.001) and in platelet 8-isoprostanes (from 177 pg/mg protein (23-387) to 90 pg/mg protein (32-182), p = 0.007). CONCLUSIONS: Low-dose dietary supplementation with omega-3 fish oils in systemic lupus erythematosus not only has a therapeutic effect on disease activity but also improves endothelial function and reduces oxidative stress and may therefore confer cardiovascular benefits.


Subject(s)
Endothelium, Vascular/physiopathology , Fatty Acids, Omega-3/administration & dosage , Lupus Erythematosus, Systemic/drug therapy , Adult , Biomarkers/blood , Brachial Artery/diagnostic imaging , Brachial Artery/drug effects , Brachial Artery/physiopathology , Cell Membrane/chemistry , Dietary Supplements , Dinoprost/analogs & derivatives , Dinoprost/blood , Docosahexaenoic Acids/analysis , Double-Blind Method , Eicosapentaenoic Acid , Endothelium, Vascular/drug effects , Endothelium, Vascular/metabolism , Fatty Acids, Unsaturated/analysis , Female , Humans , Lupus Erythematosus, Systemic/metabolism , Male , Middle Aged , Nitroglycerin , Regional Blood Flow , Statistics, Nonparametric , Treatment Outcome , Ultrasonography, Doppler, Pulsed , Vasodilation , Vasodilator Agents
18.
J Chem Phys ; 127(6): 064306, 2007 Aug 14.
Article in English | MEDLINE | ID: mdl-17705595

ABSTRACT

The photolysis of pyrrole has been studied in a molecular beam at wavelengths of 250, 240, and 193.3 nm, using two different carrier gases, He and Xe. A broad bimodal distribution of H-atom fragment velocities has been observed at all wavelengths. Near threshold at both 240 and 250 nm, sharp features have been observed in the fast part of the H-atom distribution. Under appropriate molecular beam conditions, the entire H-atom loss signal from the photolysis of pyrrole at both 240 and 250 nm (including the sharp features) disappear when using Xe as opposed to He as the carrier gas. We attribute this phenomenon to cluster formation between Xe and pyrrole, and this assumption is supported by the observation of resonance enhanced multiphoton ionization spectra for the (Xe...pyrrole) cluster followed by photofragmentation of the nascent cation cluster. Ab initio calculations are presented for the ground states of the neutral and cationic (Xe...pyrrole) clusters as a means of understanding their structural and energetic properties.


Subject(s)
Light , Photochemistry/methods , Photolysis , Pyrroles/chemistry , Xenon/chemistry , Cations , Chemistry, Physical/methods , Cluster Analysis , Electrons , Helium/chemistry , Hydrogen/chemistry , Models, Theoretical , Molecular Conformation , Photons
19.
Bone ; 41(1): 33-8, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17482901

ABSTRACT

The decline in endogenous estrogen concentration after menopause is associated with accelerated bone loss. However, effects in older women remain controversial and the usefulness of estrogen status as a predictor of spine fracture has not been assessed. Therefore, we undertook a prospective cohort study of 1350 women mean age 75 years in order to study the role of endogenous estrogen concentration on the risk of morphometric X-ray absorptiometry (MXA)-defined vertebral deformity and atraumatic clinical spine fracture and the association of endogenous estrogen with bone structure. At 5 years 70 patients (5.2%) had sustained > or = 1 incident spine fracture. The fracture group had significantly lower concentrations of baseline free estradiol index (FEI) median (IQ range) (0.38 (0.22-0.60) vs. 0.49 (0.29-0.84) pmol/nmol, p=0.009). The patients in the lowest tertile of FEI (FEI <0.35) had twice the risk of sustaining a clinical vertebral fracture compared to those subjects in the highest tertile (FEI >0.68) (HR 2.18: 95% CI 1.11-4.28). A low FEI was associated with an increased risk of a vertebral deformity over the 5-year study (OR 1.77: 95% CI 1.02-3.07) for the lowest compared to highest tertile. A low baseline FEI was associated with lower baseline QUS heel bone structure and DXA hip bone structure at 12 months and with deterioration in QUS heel bone structure 5 years later. The effect size of the FEI in predicting spine fracture was similar to the effect size for DXA BMD and heel QUS, probably because of the beneficial effect of the FEI on bone structure. The data suggest that the estrogen effect on reducing spine fracture is at least in part due to an effect on bone structure and its measurement does not significantly improve fracture prediction.


Subject(s)
Bone and Bones/pathology , Estradiol/blood , Spinal Fractures/etiology , Absorptiometry, Photon , Aged , Bone Density , Cohort Studies , Female , Humans , Risk Factors , Sex Hormone-Binding Globulin/metabolism , Spinal Fractures/blood , Spinal Fractures/metabolism , Spinal Fractures/pathology
20.
Osteoporos Int ; 18(5): 621-7, 2007 May.
Article in English | MEDLINE | ID: mdl-17143655

ABSTRACT

UNLABELLED: Meaured spinal kyphosis, as a predictor of prevalent and incident vertebral deformity, was examined in older women (>70 years) and found to not have sufficient sensitivity or specificity to justify its use as a predictor of present or future vertebral deformity risk. INTRODUCTION: Kyphosis may be attributable to vertebral deformity and was investigated as a clinical tool for predicting the presence and future risk of vertebral deformity. METHODS: Kyphosis was measured in 434 women aged 70 years or older and the kyphosis index (KI) calculated. Prevalent and incident vertebral deformities were assessed by morphometric X-ray absorptiometry (MXA). The predictive value of KI was examined. RESULTS: Severity of kyphosis was categorised by tertile of KI; 65% of anterior thoracic deformities occurred in the 33% of subjects in the highest (most kyphotic) tertile. Using this tertile as a predictor of anterior thoracic deformity, the probability for a positive test rose from 14% for the whole population to 28% and for a negative test the probability fell to 8%. For any spinal deformity the highest tertile of KI increased the probability of a positive test from 34% to 42% and reduced the probability for a negative test to 30%. The incidence of new deformities was 6% over 4 years; a high KI tertile did not increase the probability of any vertebral deformity. CONCLUSIONS: Severe kyphosis does not increase the probability of detection of a prevalent or incident spinal deformity sufficiently to make it a useful method of selecting patients for further evaluation of spinal deformity.


Subject(s)
Kyphosis/diagnosis , Spine/abnormalities , Absorptiometry, Photon , Aged , Aged, 80 and over , Female , Humans , Incidence , Kyphosis/epidemiology , Kyphosis/etiology , Lumbar Vertebrae , Predictive Value of Tests , Prevalence , Prospective Studies , ROC Curve , Severity of Illness Index , Thoracic Vertebrae , Western Australia/epidemiology
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