Effect of phosphorus limiting on phytase activity, proton efflux and oxygen consumption by nodulatedroots of common bean (Phaseolus vulgaris)

This work intended to measure the nodulated-roots oxygen consumption, proton efflux and phytase activity in 2 lines of common bean (Phaseolus vulgaris) (115, 147) at 2 levels of P supply. Rooted seedlings were inoculated with Rhizobium tropici CIAT 899 in hydroaeroponic cultivation under glasshouse. Phosphorus was supplied as KH2PO4 at 15 and 250 ìmol pl-1 week-1 (15P and 250P, respectively). Our results showed that plant growth nodulation and symbiotic nitrogen fixation were significantly affected by P limiting (15P) for the both lines, but this adverse effect was more pronounced in 147 than in 115. For the both lines, the phytase activity, higher in roots than in nodules, was significantly increased by P limiting, but 115 maintained higher values as compared to 147 line. Incotyledons, the phytase activity was higher in 115 than in 147. Phosphorus shortage increased the cumulated proton release only in 115, whereas it was lowered for 147. In this line, the proton release was linked to symbiotic nitrogen fixation. Under 15P, the proton efflux per unit of nodulated-root biomass was 25% greater for 115 than 147, suggesting that under P limitation, proton efflux may constitute an efficient way to increase P uptake in the tolerant line (115). 15P increased significantlynodulated-root O2 consumption per g nodule DW and nodule conductance, but to a higher extent in 147. As a whole, bean plants at P-deficient conditions increased the activity of phytases and proton efflux, thus maintaining the oxygen diffusion in nodules. This may represent an adaptive mechanism for N2- fixing legumes to respond to P deficiency, by increasing the utilisation and the uptake of phosphorus for symbiotic nitrogen fixation

Limited Benefit of Fish Consumption on Risk of Hip Fracture among Men in the Community-Based Hordaland Health Study

Hip fractures have a high prevalence worldwide. Few studies have investigated whether fish consumption is associated with risk of hip fractures. The objective of the present study was to investigate the effect of fish intake on the subsequent risk of a hip fracture because of the low number of studies on this topic. A community-based prospective cohort study of 2865 men and women from Hordaland county in Norway, born between 1925–1927 and enrolled in the study in 1997–1999. Information on hip fracture cases was extracted from hospital records until 31 December 2009. Baseline information on the intake of fish was obtained from a semi-quantitative food frequency questionnaire. Cox proportional hazard regression models with death as a competing risk were used to evaluate the association of fish intake with risk of hip fracture. During a mean (SD) follow-up time of 9.6 (2.7) years, 226 hip fractures (72 in men, 154 in women) were observed. The mean (SD) fish intake was 48 (25) g/1000 kcal. The association between fish intake and risk of hip fracture was not linear and displayed a threshold, with low intake of fish being associated with an increased risk of hip fracture in men (HR (Hazard Ratio) = 1.84, 95% CI 1.10, 3.08). In this community-based prospective study of men and women, a low intake of fish was associated with the risk of a hip fracture in men.publishedVersio

Serum-borne factors in cancer patients with advanced cachexia: influence on adipose cells

Background: The clinical syndrome cancer cachexia is recognized by a considerable weight loss being out of proportion to any reduction in energy intake. The underlying mechanisms are not completely known, but the marked weight loss is attributable to depletion of adipose tissue as well as skeletal muscle mass. Enhanced lipolysis in adipocytes, apoptosis of preadipocytes may be important for loss of adipose tissue.Results: Sera from cachectic cancer patients induced apoptosis in cultured human preadipocytes at a higher rate than sera from non-cachectic cancer patients (control group). There was a tendency towards increased mRNA levels of the pro-apoptotic Bcl-2 gene Bax after incubation of preadipocytes with cachectic sera. Moreover, the mRNA levels of anti-apoptotic Bcl-XL and pro-apoptotic Bcl-XS were increased and decreased, respectively, as compared to incubation with control sera. However, lipolysis was not enhanced in cultured human adipocytes after incubation with sera from cachectic cancer patients as compared to non-cachectic cancer patients.Methods: Serum samples from cachectic cancer patients (n=8) and non-cachectic cancer patients (n=6) were collected. Human SGBS (Simpson-Golabi-Behmel syndrome) preadipocytes and differentiated adipocytes were incubated in the presence of serum from cachectic and non-cachectic (control) cancer patients. Induction of apoptosis and necrosis was examined by cell staining with Hoechst 342 (HO342) and propidium iodide (PI), respectively. Expression of pro- and anti-apoptotic Bcl-2 genes was measured by quantitative RT-PCR. Lipolysis was monitored by measuring the release of radiolabeled fatty acids.Conclusion: Our in vitro data suggest that apoptosis of preadipocytes can be increased by serum-borne factors in cancer cachexia. Death or survival of preadipocytes may depend on the balance of pro- and anti-apoptotic mediators. Further studies of patients with cancer cachexia will be needed to reveal if the disease involves loss of adipose tissue due to apoptosis of preadipocytes. We could not show that serum-borne factors associated with cachexia have a major impact on lipolysis in cultured human adipocytes.Adipobiology 2009; 1: 57-66

Plasma free choline, betaine and cognitive performance: the Hordaland Health Study

Choline and betaine are nutrients involved in one-carbon metabolism. Choline is essential for neurodevelopment and brain function. We studied the associations between cognitive function and plasma concentrations of free choline and betaine. In a cross-sectional study, 2195 subjects (55 % women), aged 70–74 years, underwent extensive cognitive testing including the Kendrick Object Learning Test (KOLT), Trail Making Test (part A, TMT-A), modified versions of the Digit Symbol Test (m-DST), Block Design (m-BD), Mini-Mental State Examination (m-MMSE) and Controlled Oral Word Association Test (COWAT). Compared with low concentrations, high choline (>8·4 μmol/l) was associated with better test scores in the TMT-A (56·0 v. 61·5, P= 0·004), m-DST (10·5 v. 9·8, P= 0·005) and m-MMSE (11·5 v. 11·4, P= 0·01). A generalised additive regression model showed a positive dose–response relationship between the m-MMSE and choline (P= 0·012 from a corresponding linear regression model). Betaine was associated with the KOLT, TMT-A and COWAT, but after adjustments for potential confounders, the associations lost significance. Risk ratios (RR) for poor test performance roughly tripled when low choline was combined with either low plasma vitamin B12 ( ≤ 257 pmol/l) concentrations (RRKOLT= 2·6, 95 % CI 1·1, 6·1; RRm-MMSE= 2·7, 95 % CI 1·1, 6·6; RRCOWAT= 3·1, 95 % CI 1·4, 7·2) or high methylmalonic acid (MMA) ( ≥ 3·95 μmol/l) concentrations (RRm-BD= 2·8, 95 % CI 1·3, 6·1). Low betaine ( ≤ 31·1 μmol/l) combined with high MMA was associated with elevated RR on KOLT (RRKOLT= 2·5, 95 % CI 1·0, 6·2). Low plasma free choline concentrations are associated with poor cognitive performance. There were significant interactions between low choline or betaine and low vitamin B12 or high MMA on cognitive performance.publishedVersio

Improvement of legume productivity and role of symbiotic nitrogen fixation in cropping systems: Overcoming the physiological and agronomic limitations

Nitrogen-fixing legumes can meet most of their N-needs through symbiotic nitrogen fixation (SNF). However, in most cases, inclusion of a legume in a cropping system does not ensure the attainment of such levels ofSNF in the field. Several environmental factors including drought, temperature and soil nutrient status dramatically affect the process at molecular/functional level and thus playa part in determining the actual amount of nitrogen fixed by a given legume in the field. lhis chapter reviews the status of SNF in response to most significant environmental constraints, and focuses on specific cases of harnessing SNF by improving its tolerance to stress factors with tI1.e aim of enhancing system productivity. Several examples are discussed, including the selection of legume crops tolerant to drought and salinity and/or allowing high biomass production and solubilization of phosphorus, identifying high nitrogen-fixing and nilrate-N tolerant genotypes and their inclusion in relevant cropping systems, and changes in agronomical management practices for better integration of legumes in cereal cropping systems. Finally, a general framework is discussed for agro-physiological contributions that can help overcome SNF limitation by environmental constraints. The on-farm application of these knowledge-based SNF technologies will strengthen the role of N2-fixing legumes in cropping system

Intestinal microbiota development and gestational age in preterm neonates

The intestinal microbiota is an important contributor to the health of preterm infants, and may be destabilized by a number of environmental factors and treatment modalities. How to promote the development of a healthy microbiota in preterm infants is largely unknown. We collected fecal samples from 45 breastfed preterm very low birth weight (birth weight <1500 g) infants from birth until 60 days postnatal age to characterize the intestinal microbiota development during the first weeks of life in preterm infants. Fecal microbiota composition was determined by 16S rRNA amplicon sequencing. The main driver of microbiota development was gestational age; antibiotic use had strong but temporary effects and birth mode had little influence. Microbiota development proceeded in four phases indicated by the dominance of Staphylococcus, Enterococcus, Enterobacter, and finally Bifidobacterium. The Enterococcus phase was only observed among the extremely premature infants and appeared to delay the microbiota succession. The results indicate that hospitalized preterm infants receiving breast milk may develop a normal microbiota resembling that of term infants.Peer reviewe