Nitrogen processing by treatment wetlands in a tropical catchment dominated by agricultural landuse.

Agriculture is a major contributor to marine nitrogen pollution, and treatment wetlands can be a strategy to reduce it. However, few studies have assessed the potential of treatment wetlands to mitigate nitrogen pollution in tropical regions. We quantify the nitrogen removal rates of four recently constructed treatment wetlands in tropical Australia. We measured denitrification potential (Dt), the inflow-outflow of nutrients, and tested whether the environment in these tropical catchments is favourable for nitrogen removal. Dt was detected in three of the four systems with rates between 2.0 and 12.0 mg m-2 h-1; the highest rates were measured in anoxic soils (ORP -100 to 300 mV) that were rich in carbon and nitrogen (>2% and >0.2%, respectively). The highest nitrogen removal rates were measured when NO3--N concentrations were >0.4 mg L-1 and when water flows were slow. Treatment wetlands in tropical regions can deliver high removal rates of nitrogen and other pollutants when adequately managed. This strategy can reduce nutrient loads and their impacts on sensitive coastal zones such as the Great Barrier Reef.

Cost-effectiveness analysis of treatment strategies for initial Clostridium difficile infection.

Clostridium difficile infection (CDI) is costly. Current guidelines recommend metronidazole as first-line therapy and vancomycin as an alternative. Recurrence is common. Faecal microbiota transplantation (FMT) is an effective therapy for recurrent CDI (RCDI). This study explores the cost-effectiveness of FMT, vancomycin and metronidazole for initial CDI. We constructed a decision-analytic computer simulation using inputs from published literature to compare FMT with a 10-14-day course of oral metronidazole or vancomycin for initial CDI. Parameters included cure rates (baseline value (range)) for metronidazole (80% (65-85%)), vancomycin (90% (88-92%)) and FMT(91% (83-100%)). Direct costs of metronidazole, vancomycin and FMT, adjusted to 2011 dollars, were $57 ($43-72), $1347 ($1195-1499) and $1086 ($815-1358), respectively. Our effectiveness measure was quality-adjusted life years (QALYs). One-way and probabilistic sensitivity analyses were conducted from the third-party payer perspective. Analysis using baseline values showed that FMT($1669, 0.242 QALYs) dominated (i.e. was less costly and more effective) vancomycin ($1890, 0.241 QALYs). FMT was more costly and more effective than metronidazole ($1167, 0.238 QALYs), yielding an incremental cost-effectiveness ratio (ICER) of $124 964/QALY. One-way sensitivity analyses showed that metronidazole dominated both strategies if its probability of cure were >90%; FMT dominated if it cost <$584. In a probabilistic sensitivity analysis at a willingness-to-pay threshold of $100 000/QALY, metronidazole was favoured in 55% of model iterations; FMT was favoured in 38%. Metronidazole, as the first-line treatment for CDIs, is less costly. FMT and vancomycin are more effective. However, FMT is less likely to be economically favourable, and vancomycin is unlikely to be favourable as first-line therapy when compared with FMT.

[Seperation and structure elucidation of alkaloids from Chinese drug buzhaye, Folium Microcos].

From the chloroform extracts of the dried Folium Microcos, four compounds were isolated by using repeated column chromatography on silica gel and recrystallization and their structures were elucidated by physicochemical properties and UV, MS and NMR, separately. They are N-methyl-6alpha-(deca-1', 3', 5'-trienyl)-3beta-methoxy-2beta-methylpiperidine, 6-(deca-1', 3', 5'-trienyl)-3-methoxy-2-methylpiperidine, N-methyl-6-(deca-1', 3', 5'-trienyl)-2, 3-dimethylpiperidine and N-methyl-6-(deca-1', 3', 5'-trienyl)-2-methylpiperidine, named as micropiperidine A, micropiperidine B, micropiperidine C and micropiperidine D, respectively. The latter three are new compounds.

Comparison of broiler performance when fed diets containing event DP-3O5423-1, nontransgenic near-isoline control, or commercial reference soybean meal, hulls, and oil.

DP-3Ø5423-1 (305423) is a genetically modified soybean that was produced by biolistic insertion of the gm-fad2-1 gene fragment and gm-hra genes into the germline of soybean seeds. Expression of gm-fad2-1 results in greater concentrations of oleic acid (18:1) by suppressing expression of the endogenous FAD2-1 gene, which encodes an n-6 fatty acid desaturase enzyme that catalyzes desaturation of 18:1 to linoleic acid (18:2). The GM-HRA protein expressed by the gm-hra gene is a modified version of the soybean acetolactate synthase enzyme that is used as a selectable marker during transformation. A 42-d feeding trial was conducted with broiler chickens to compare the nutritional performance of 305423 soybeans with nontransgenic soybeans. Diets were prepared using processed fractions (meal, hulls, and oil) from 305423 soybean plants. For comparison, additional diets were produced with soybean fractions obtained from a nontransgenic near-isoline (control) and nontransgenic commercial Pioneer brand varieties (93B86, 93B15, and 93M40). Diets were fed to Ross x Cobb broilers (n = 120/group, 50% male and 50% female) in 3 phases. Starter, grower, and finisher diets contained 26.5, 23, and 21.5% soybean meal, respectively. Soybean hulls and oil were added at 1.0 and 0.5%, respectively, across all diets in each phase. No statistically significant differences were observed in growth performance (BW, mortality, feed efficiency), organ yield (liver and kidney), or carcass yield (breast, thigh, leg, wing, and abdominal fat) variables between broilers consuming diets prepared with isolated fractions from 305423 or near-isoline control soybean. Additionally, all performance and carcass variables from control and 305423 soybean treatment groups fell within tolerance intervals constructed for each response variable using data from broilers fed diets prepared with reference soybean fractions. Based on the results from this study, it was concluded that 305423 soybeans were nutritionally equivalent to non-transgenic control soybeans with a comparable genetic background.

Comparison of broiler performance when fed diets containing event DP-356Ø43-5 (Optimum GAT), nontransgenic near-isoline control, or commercial reference soybean meal, hulls, and oil.

Event DP-356Ø43-5 (356043; Optimum GAT) is a genetically modified soybean (Glycine max) that was produced by insertion of the gat4601 and gm-hra genes. The expression products of these genes are the glyphosate acetyltransferase 4601 and acetolactate synthase proteins, respectively. Expression of the glyphosate acetyltransferase 4601 protein confers tolerance in planta to the herbicidal active ingredient glyphosate, whereas expression of the acetolactate synthase protein confers tolerance to sulfonylurea and imidazolinone herbicides. The objective of this study was to compare the nutritional equivalence of 356043 soybeans to nontransgenic soybeans in a 42-d feeding trial in broiler chickens. Diets were prepared using processed fractions (meal, hulls, and oil) from untreated 356043 soybean plants or from soybean plants treated with a mixture of glyphosate, chlorimuron, and thifensulfuron (356043 + Gly/SU). For comparison, additional diets were produced with soybean fractions obtained from a nontransgenic near-isoline (control; 091) and nontransgenic commercial Pioneer varieties (93B86, 93B15, and 93M40). Diets were fed to Ross x Cobb broilers (n = 120/group, 50% male and 50% female) in 3 phases. Starter diets contained 30% soybean meal, grower diets 26% soybean meal, and finisher diets 21.5% soybean meal. Soybean hulls and oil were added at 1.0 and 0.5%, respectively, across all diets in each phase. No statistically significant differences were observed in mortality, growth performance variables, or carcass and organ yields between broilers consuming diets produced with 356043 or 356043 + Gly/SU soybean fractions and those consuming diets produced with near-isoline control soybean fractions. Additionally, all performance and carcass variables from control, 356043, and 356043 + Gly/SU soybean treatment groups fell within the tolerance intervals constructed using data from reference soybean groups. Based on the results from this study, it was concluded that 356043 soybean was nutritionally equivalent to nontransgenic control soybean with a comparable genetic background.

Fish oil for kidney transplant recipients.

BACKGROUND: Calcineurin inhibitors used in kidney transplantation for immunosuppression have adverse effects that may contribute to nephrotoxicity and increased cardiovascular risk profile. Fish oils are rich in very long chain omega-3 fatty acids, which may reduce nephrotoxicity by improving endothelial function and reduce rejection rates through their immuno-modulatory effects. They may also modify the cardiovascular risk profile. Hence, fish oils may potentially prolong graft survival and reduce cardiovascular mortality. OBJECTIVES: To assess the benefits and harms of fish oil supplementation on kidney transplant recipients on a calcineurin inhibitor-based immunosuppressive regimen. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL in The Cochrane Library, issue 2 2005), MEDLINE (1966-April 2005) and EMBASE (1980-April 2005). SELECTION CRITERIA: All randomised controlled trials (RCTs) and quasi-RCTs of fish oils in kidney transplant recipients on a calcineurin inhibitor-based immunosuppressive regimen. RCTs of fish oil versus statins were included. DATA COLLECTION AND ANALYSIS: Data was extracted and the quality of studies assessed by two authors, with differences resolved by discussion with a third independent author. Dichotomous outcomes were reported as relative risk (RR) and continuous outcome measures were reported as the mean difference (MD) with 95% confidence intervals using the random effects model. Heterogeneity was assessed using a Chi(2) test on n-1 degrees of freedom and the I(2) statistic. Data not suitable for pooling were tabulated and described. MAIN RESULTS: Sixteen studies (733 patients) were suitable for analysis. Fish oil did not significantly affect patient or graft survival, acute rejection rates, calcineurin inhibitor toxicity or renal function, when compared to placebo. Fish oil treatment was associated with a lower diastolic blood pressure (MD 4.5 mmHg; P = 0.004) compared to placebo. Patients receiving fish oil for more than six months had a modest increase in HDL (MD 0.12 mmol/L; P = 0.01) compared to placebo. Fish oil effects on lipids were not significantly different from low-dose statins. There was insufficient data to analyse cardiovascular outcomes. Fishy aftertaste and gastrointestinal upset were common but did not result in significant patient drop-out. AUTHORS' CONCLUSIONS: There is insufficient evidence from currently available RCTs to recommend fish oil therapy to improve renal function, rejection rates, patient survival or graft survival. The improvements in HDL cholesterol and diastolic blood pressure were too modest to recommend routine use. To determine a benefit in clinical outcomes, future RCTs will need to be adequately powered with these outcomes in mind.

Colposcopic management of high-grade referral smears: a retrospective audit supporting 'see and treat'?

OBJECTIVE: The National Health Service Cervical Screening Programme monitors the quality of colposcopy services through the annual KC65 returns. The 2002 returns demonstrated that Standard 7c, which specifies a biopsy rate > or = 90% at first colposcopy visit for high-grade referrals, was not met in the assessed 3-month period. This was investigated along with the other standards. METHODS: Retrospective colposcopy records were accessed for the 597 new referrals, excluding 10 pregnant patients, seen at the colposcopy clinic at the Royal Victoria Infirmary between 1 July 2001 and 31 December 2002, following an abnormal high-grade smear. Cytology and histopathology computer records were checked for confirmation. The results were assessed against the colposcopy standards applicable at that time and the revised standards (2004). RESULTS: Biopsies were taken from 94.47% (Standard > or = 90%) of women at index colposcopy visit including wire loop excision biopsies from 66.16% (87.97% of high-grade colposcopic appearances). Cervical intraepithelial neoplasia (CIN) on histology was found in 91.79% in the study group (Standard > or = 85%) and in 96.71% of index visit biopsies (Standard > or = 90%), meeting the applicable colposcopy standards. The revised 2004 standards specify a biopsy in > or = 95% of high-grade referrals and excision biopsies in 95% if colposcopic appearances are also high-grade, if colposcopy is low grade but the smear is severely dyskaryotic, or when the lesion extends into the canal. The positive predictive value of high-grade cytology for this entire group was 75.54% with CIN present in 90.95%. CONCLUSION: From this study it appears that high-grade cytology in this centre reliably indicates high-grade CIN. Therefore, in women referred for colposcopy following a high-grade smear, excision biopsies should be performed in a higher proportion at the first visit to comply with the revised standards.

Acrylamide reduction in processed foods.

The discovery of the formation of acrylamide in fried and baked foods containing high levels of starch and the amino acid asparagine, prompted widespread concern. Both processed and home cooked foods are affected and this has led to the increased study of variations in cooking and processing conditions to minimize formation. While changes in cooking protocols have been in part successful, particularly when lower frying and baking temperatures are used, pretreatments to reduce levels of acrylamide by prevention of formation or acceleration of destruction have been investigated. In this study, a range of pretreatments of grilled potato were investigated and compared with surface washing to remove asparagine and reducing sugars. Synergies were observed between different treatments, and reductions of up to 40% were achieved in a non-optimized system.

Effect of menhaden fish oil supplementation and lipopolysaccharide exposure on nursery pigs. I. Effects on the immune axis when fed diets containing spray-dried plasma.

The objective of the present study was to evaluate the potential immunological benefit of adding menhaden fish oil to the diet of weaned pigs. Twenty-four crossbred male pigs were weaned at approximately 18 days of age and placed on a complex nursery diet containing 30% lactose and 7% plasma protein with 6% corn oil as the fat source (Cont, n=12) or with 5% menhaden fish oil and 1% corn oil as the fat source (MFO, n=12) for a period of 15 days. Body weights did not differ (P>0.78) between dietary groups either at the beginning or end of the 15 days feeding period. On day 15, all pigs were non-surgically fitted with an indwelling jugular catheter. On d 16, pigs received an i.v. injection of either saline (n=6/dietary group) or lipopolysaccharide (LPS; 150 microg/kg body weight; n=6/dietary group) and blood samples were collected at 30 min intervals for a period of 5h. Serum was harvested and stored at -80 degrees C for analysis of cortisol (CS), corticosteroid-binding globulin (CBG), tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). There was no significant effect of diet on basal concentrations (Time 0) of any of the blood parameters analyzed. A Time x Treatment x Diet interaction (P<0.03) was observed for serum CS such that those pigs which consumed the MFO diet followed by LPS treatment had a reduced CS response as compared to the LPS-treated pigs on the Cont diet. A Time x Treatment interaction (P<0.01) was observed for serum CBG such that LPS treatment reduced circulating CBG as compared to the saline-treated pigs. Time x Treatment x Diet interactions were also observed for serum concentrations of TNF-alpha (P=0.084) and IFN-gamma (P=0.022) such that both the TNF-alpha and IFN-gamma response to the LPS challenge was lower in those pigs receiving the MFO diet as compared to the LPS-treated pigs on the Cont diet. Overall, serum CS was negatively correlated with the CBG response (r=-0.40, P<0.001), however, the strongest negative correlation was observed in the LPS-treated pigs which consumed the MFO diet (r=-0.63, P<0.001). While further studies are needed to evaluate the immunological response of including MFO in the nursery pig diet, the present study demonstrates that supplementation with MFO does indeed alter the immunological response to an LPS challenge.

Protein energy supplements in unwell elderly patients--a randomized controlled trial.

BACKGROUND: To determine whether oral protein energy supplements, prescribed during hospitalization to elderly medical admissions, affect nutritional status and if baseline nutritional state influences this status. We also considered the effects on mortality, length of hospital stay, functional recovery, and institutionalization. METHODS: A prospective randomized controlled trial with no placebo. Consenting patients were stratified in 3 nutritional categories, and patients from each stratum were randomized into treatment or control. Observers were blinded to randomization. The participants were emergency admissions from home to a Medicine for the Elderly Unit in a Scottish hospital. The inclusion criteria were as follows: no known malignancy, the ability to swallow, and nonobesity (BMI < 75th percentile). The intervention was a prescription of 120 mL sip feed, 3 times daily (540 kcal, 22.5 g protein per day) throughout hospitalization, using the medicine prescription chart. The trial was powered to detect change in mean percentage weight. The following outcomes were also considered: anthropometry; mortality, length of hospital stay, functional recovery, and rates of institutionalization. RESULTS: Included in the trial were 381 patients. Nutritional supplementation was associated with significantly better energy intake (p = .001) and weight gain (p = .003) pooled across all nutritional categories. In the most poorly nourished patients, the intervention was associated with reduced mortality (5/34 versus 14/40, p < .05) and more patients improved functionally (17/25 versus 11/28, p < .04). Overall mortality results were 21/186 versus 33/195, odds ratio (OR) 0.62, 95% confidence interval (CI) 0.35, 1.13. CONCLUSIONS: Prescribing sip feed supplements in the medicine prescription chart during hospital stay reduces weight loss. Our data also support other evidence for a reduction in mortality noted in elderly patients on nutritional supplementation. There were suggestions of other clinical benefits.

Influence of supplemental, dietary vitamin A on retinol-binding protein concentrations in the plasma of preruminant calves.

Transport of retinol (vitamin A alcohol) from retinoid stores in the liver to target tissues is accomplished exclusively by a specific plasma protein, retinol-binding protein. Within individuals, retinol-binding protein concentrations in plasma are regulated and remain constant except in extremes of vitamin A nutriture or in disease. In the present study, retinol-binding protein concentrations in plasma from preruminant calves supplemented with 0, 1700 (i.e., current NRC requirement), 34,000, or 68,000 IU of vitamin A daily from birth to 27 d of age (n = 6/treatment) were quantified. Retinol-binding protein concentrations at birth averaged 21 microg/ml (n = 24) or approximately 50% of concentrations in dairy heifers and cows. Plasma retinol and retinol-binding protein concentrations were correlated positively, corroborating the role of vitamin A nutriture in the regulation of retinol-binding protein secretion from the liver. In this regard, dietary vitamin A influenced positively retinol and retinol-binding protein concentrations and, as a consequence, the degree of saturation of retinol-binding protein with retinol. At 27 d of age, calves fed > or = 34,000 IU of vitamin A had substantially higher retinol and retinol-binding protein concentrations than did calves fed < or = 1700 IU of vitamin A, indicating that dietary vitamin A effects positively vitamin A status. The data also suggest that the current NRC requirement may not be sufficient to assure vitamin A adequacy in preruminant calves. Percent saturation of retionol-binding protein with retinol in all calves was < 35%, much lower than anticipated and suggests that the retinol requirement of vitamin A-responsive tissues exceeded vitamin A availability.

Matching prescription claims with medication data for nursing home residents: implications for prescriber feedback, drug utilisation studies and selection of prescription claims database.

Medication data retrieved from Australian Repatriation Pharmaceutical Benefits Scheme (RPBS) claims for 44 veterans residing in nursing homes and Pharmaceutical Benefits Scheme (PBS) claims for 898 nursing home residents were compared with medication data from nursing home records to determine the optimal time interval for retrieving claims data and its validity. Optimal matching was achieved using 12 weeks of RPBS claims data, with 60% of medications in the RPBS claims located in nursing home administration records, and 78% of medications administered to nursing home residents identified in RPBS claims. In comparison, 48% of medications administered to nursing home residents could be found in 12 weeks of PBS data, and 56% of medications present in PBS claims could be matched with nursing home administration records. RPBS claims data was superior to PBS, due to the larger number of scheduled items available to veterans and the veteran's file number, which acts as a unique identifier. These findings should be taken into account when using prescription claims data for medication histories, prescriber feedback, drug utilisation, intervention or epidemiological studies.

The use of cyclic voltammetry for the evaluation of antioxidant capacity.

Low-molecular weight antioxidants (LMWAs) play a major role in protecting biological systems against reactive oxygen-derived species and reflect the antioxidant capacity of the system. Cyclic voltammetry (CV), shown to be convenient methodology, has been validated for quantitation of the LMWA capacity of blood plasma, tissue homogenates, and plant extracts. Analysis of the CV tracing yields the values of (i) the biological oxidation potential, E and E(1/2), which relate to the nature of the specific molecule(s); (ii) the intensity (Ia) of the anodic current; and (iii) the area of the anodic wave (S). Both Ia and S relate to the concentration of the molecule(s). LMWA components of human plasma and animal tissues were identified and further validated by reconstruction of the CV tracing and by high-performance liquid chromatography-electrochemical detection. To reflect the oxidative stress status, the use of an additional parameter, R, has been proposed. R represents the level (%) of oxidized ascorbate (compared with total ascorbate) and is measured by high-performance liquid chromatography-electrochemical detection. All these parameters were monitored in healthy human subjects as well as in chronic (diabetes mellitus) and acute care patients (subjected to total body irradiation before bone marrow transplantation). The electroanalytical methodologies presented here could be widely employed for rapid evaluation of the status of subjects (in health and disease) for monitoring of their response to treatment and/or nutritional supplementation as well as for screening of specific populations.

Correlates of quantitative ultrasound in the Women's Healthy Lifestyle Project.

Quantitative ultrasound (QUS) assessment of bone is a strong predictor of hip fractures and is currently an FDA-approved tool to identify women at risk of osteoporosis. However, few studies have investigated the lifestyle and genetic correlates of QUS in women. This study investigated the cross-sectional associates of several lifestyle, demographic and genetic factors with calcaneal QUS parameters (broadband ultrasound attenuation (BUA) and speed of sound (SOS)) in 393 women aged 45-53 years. Leisure-time and historical physical activity, dietary calcium and protein, body composition, vitamin D receptor genotypes, menopause status, other health behaviors, calcaneal QUS parameters and bone mineral density (BMD) were assessed at a single clinic visit. Lean mass, recent physical activity and African-American race were the strongest correlates of SOS whereas dietary protein, calcium and recent physical activity were the strongest correlates of BUA. These predictors explained 13% and 6% of the variance in SOS and BUA, respectively. Smoking, alcohol intake, education, hormone replacement therapy, calcium and vitamin D supplements, historical physical activity and vitamin D receptor genotypes were not significantly associated with BUA or SOS. Lean body mass and premenopausal status were the strongest correlates of lumbar BMD whereas lean body mass, physical activity, African-American race and body mass index were significantly related to femoral neck BMD. Physical activity remained predictive of SOS after controlling for lumbar BMD. The spectrum and magnitude of risk factors for SOS and BUA, including lean body mass, physical activity, race, protein and calcium intake, parallel previously observed predictors of BMD.

Myeloperoxidase activity of the large intestine in an equine model of acute colitis.

OBJECTIVE: To determine whether quantification of myeloperoxidase (MPO) activity could be a useful laboratory technique to detect granulocyte infiltration in equine intestinal tissues. SAMPLE POPULATION: Intestinal tissue (inflamed or healthy) collected from 16 age- and sex-matched Shetland Ponies. PROCEDURE: Intestinal tissue MPO activity was determined, and histologic assessment of adjacent specimens from healthy and inflamed intestine was done. RESULTS: Intestinal tissue MPO activity and histopathologic score increased with time after castor oil challenge and peaked at 16 hours in an equine diarrhea model in which individual ponies provided their own control tissues. CONCLUSIONS: Intestinal tissue inflammation scores correlated positively with tissue MPO activity in adjacent specimens. CLINICAL RELEVANCE: Tissue MPO assay may be a useful laboratory tool to quantify intestinal mucosal inflammation in ponies.

The efficacy of exercise as an aid for smoking cessation in women: a randomized controlled trial.

BACKGROUND: Smoking prevalence rates among women are declining at a slower rate than among men. OBJECTIVE: To determine if exercise, a healthful alternative to smoking, enhances the achievement and maintenance of smoking cessation. METHODS: Two hundred eighty-one healthy, sedentary female smokers were randomly assigned to either a cognitive-behavioral smoking cessation program with vigorous exercise (exercise) or to the same program with equal staff contact time (control). Subjects participated in a 12-session, group-based smoking cessation program. Additionally, exercise subjects were required to attend 3 supervised exercise sessions per week and control subjects were required to participate in 3 supervised health education lectures per week. Abstinence from smoking was based on self-report, was verified by saliva cotinine level, and was measured at 1 week after quit day (week 5), end of treatment (week 12), and 3 and 12 months later (20 and 60 weeks after quit day, respectively). RESULTS: Compared with control subjects (n = 147), exercise subjects (n = 134) achieved significantly higher levels of continuous abstinence at the end of treatment (19.4% vs 10.2%, P = .03) and 3 months (16.4% vs 8.2%, P=.03) and 12 months (11.9% vs 5.4%, P=.05) following treatment. Exercise subjects had significantly increased functional capacity (estimated VO2 peak, 25+/-6 to 28+/-6, P<.01) and had gained less weight by the end of treatment (3.05 vs 5.40 kg, P = .03). CONCLUSIONS: Vigorous exercise facilitates short- and longer-term smoking cessation in women when combined with a cognitive-behavioral smoking cessation program. Vigorous exercise improves exercise capacity and delays weight gain following smoking cessation.

Ferrioxamine-mediated Iron(III) utilization by Salmonella enterica.

Utilization of ferrioxamines as sole sources of iron distinguishes Salmonella enterica serotypes Typhimurium and Enteritidis from a number of related species, including Escherichia coli. Ferrioxamine supplements have therefore been used in preenrichment and selection media to increase the bacterial growth rate while selectivity is maintained. We characterized the determinants involved in utilization of ferrioxamines B, E, and G by S. enterica serotype Typhimurium by performing siderophore cross-feeding bioassays. Transport of all three ferric siderophores across the outer membrane was dependent on the FoxA receptor encoded by the Fur-repressible foxA gene. However, only the transport of ferrioxamine G was dependent on the energy-transducing protein TonB, since growth stimulation of a tonB strain by ferrioxamines B and E was observed, albeit at lower efficiencies than in the parental strain. Transport across the inner membrane was dependent on the periplasmic binding protein-dependent ABC transporter complex comprising FhuBCD, as has been reported for other hydroxamate siderophores of enteric bacteria. The distribution of the foxA gene in the genus Salmonella, as indicated by DNA hybridization studies and correlated with the ability to utilize ferrioxamine E, was restricted to subspecies I, II, and IIIb, and this gene was absent from subspecies IIIa, IV, VI, and VII (formerly subspecies IV) and Salmonella bongori (formerly subspecies V). S. enterica serotype Typhimurium mutants with either a transposon insertion or a defined nonpolar frameshift (+2) mutation in the foxA gene were not able to utilize any of the three ferrioxamines tested. A strain carrying the nonpolar foxA mutation exhibited a significantly reduced ability to colonize rabbit ileal loops compared to the foxA+ parent. In addition, a foxA mutant was markedly attenuated in mice inoculated by either the intragastric or intravenous route. Mice inoculated with the foxA mutant were protected against subsequent challenge by the foxA+ parent strain.

Etiology and treatment of intrinsic circadian rhythm sleep disorders.

Some individuals experience an acute or chronic sleep disturbance, associated with a misalignment between the timing of their sleep and the sleep-wake cycle that is desired, or considered normal by society. It is estimated that 5-10% of insomniacs seeking treatment have this type of disorder, collectively called circadian rhythm sleep disorders. This paper reviews circadian rhythm sleep disorders of the intrinsic type, which include delayed sleep phase syndrome, advanced sleep phase syndrome, non-24-hour sleep-wake syndrome, and irregular sleep-wake pattern. For each disorder, we present data addressing its pathophysiology and potential treatments, including the use of behavioral measures and chronotherapy, bright light treatment and pharmacological treatments such as melatonin. We conclude by addressing some of the limitations and drawbacks of the various treatments.

Routine protein energy supplementation in adults: systematic review.

OBJECTIVES: To determine whether routine oral and enteral nutritional supplementation can improve the weight, anthropometry, and survival of adult patients. DESIGN: Systematic review of randomised controlled trials of oral or enteral protein supplementation in adults. Trials were identified from Medline (Silver Platter 3.11, 1966-96), reference lists of identified studies and review articles, and communication with feed manufacturers. SUBJECTS: Randomised controlled trials comparing oral or enteral protein supplementation with no routine supplementation. All trials of adult subjects were included except those addressing nutrition in pregnancy. MAIN OUTCOME MEASURES: Change in body weight and anthropometry (mid-arm muscle circumference), and all cause case fatality recorded at the end of scheduled follow up. Body weight and anthropometry were analysed as the weighted mean difference and 95% confidence intervals of the percentage change in these variables. Case fatality was analysed with odds ratio and 95% confidence intervals. RESULTS: 32 eligible reports (2286 randomised patients) published between February 1979 and July 1996 were identified, of which 30 (93.8%) (2062 randomised patients) reported outcomes of interest. Case fatality data were available for 1670 (81%) patients, and continuous variable data for up to 1607 (78%) patients. The treatment group receiving routine nutritional supplementation showed consistently improved changes in body weight and anthropometry compared with controls; weighted mean difference 2.06% (95% confidence interval 1.63% to 2.49%) and 3.16% (2.43% to 3.89%) respectively. The pooled odds ratio for death in the treatment group was 0.66 (0.48 to 0.91, 2P<0.01). Apparent benefits were observed in several prespecified subgroups of patients, treatment settings, and interventions, but were not evident if trials with less robust methodology were excluded. CONCLUSIONS: Routine oral or enteral supplementation seems to improve the nutritional indices of adult patients, but there are insufficient data in trials which meet strict methodological criteria to be certain if mortality is reduced. Benefits were not restricted to particular patient groups. Further large pragmatic randomised controlled trials of routine nutritional supplementation are justified.