Assessment of physical performance and body composition in male renal transplant patients.

BACKGROUND: Renal transplant (RTX) recipients seem to experience a better quality of life compared to dialysis patients. However, the factors responsible for this positive effect are not completely defined. Conceivably, a change in the physical performance of these patients could play a role. METHODS: To assess this, we measured: (1) waist circumference, fat mass and appendicular fat-free mass (aFFM) by dual-energy X-ray densitometry, (2) physical performance with the Short Physical Performance Battery, and (3) muscle strength with the handgrip test, in 59 male RTX, 11 chronic kidney disease in conservative treatment (CKD) and 10 peritoneal dialysis (PD) patients. RESULTS: Surprisingly, anthropometric characteristics and body composition were similar among the three groups. However, despite a low aFFM, muscle strength was higher in stable RTX recipients > 5 years after transplantation than in dialyzed patients. Instead, CKD (wait-listed for RTX) had similar muscle strength to RTX patients. Waist circumference in RTX recipients showed a redistribution of body fat with increased central adipose tissue allocation compared to PD. At linear regression analysis, age, weight, height, aFFM, hemoglobin and transplant age were independent predictors of handgrip strength, explaining about 37% of the variance. Age and transplant age accounted for 18 and 12% of variance, respectively. CONCLUSIONS: Our study demonstrates, for the first time, that clinically stable RTX recipients have greater muscle strength than dialyzed patients and suggests that the handgrip test could be an effective and easy-to-perform tool to assess changes in physical performance in this large patient population.

Modeling quorum sensing trade-offs between bacterial cell density and system extension from open boundaries.

Bacterial communities undergo collective behavioural switches upon producing and sensing diffusible signal molecules; a mechanism referred to as Quorum Sensing (QS). Exemplarily, biofilm organic matrices are built concertedly by bacteria in several environments. QS scope in bacterial ecology has been debated for over 20 years. Different perspectives counterpose the role of density reporter for populations to that of local environment diffusivity probe for individual cells. Here we devise a model system where tubes of different heights contain matrix-embedded producers and sensors. These tubes allow non-limiting signal diffusion from one open end, thereby showing that population spatial extension away from an open boundary can be a main critical factor in QS. Experimental data, successfully recapitulated by a comprehensive mathematical model, demonstrate how tube height can overtake the role of producer density in triggering sensor activation. The biotic degradation of the signal is found to play a major role and to be species-specific and entirely feedback-independent.

Dynapenic abdominal obesity as predictor of mortality and disability worsening in older adults: A 10-year prospective study.

UNLABELLED: There are relatively few prospective studies evaluating the combined effect of abdominal obesity and low muscle strength on worsening disability and on mortality. The study aimed at evaluating prospectively the prognostic value of dynapenic abdominal obesity definition on disability worsening in a 5.5-year follow-up and mortality in a 10-year follow-up. METHODS: In 93 men and 169 women aged between 66 and 78 years, leg isometric strength, waist circumference (WC), BMI, glycemia, HOMA, lipid profile, vitamin D3, albumin, fibrinogen, physical activity level, income, smoking status and comorbidities were evaluated at the baseline. Reported disabilities were measured at baseline, 1-y, 2-y, 3-y and 5.5-y follow-up and mortality rate was evaluated during a 10-y follow-up. The study population was categorized in dynapenic abdominal obese (D/AO), nondynapenic abdominal obese (ND/AO), dynapenic nonabdominal obese (D/NAO), nondynapenic nonabdominal obese (ND/NAO) according to muscle strength/WC tertiles. RESULTS: D/NAO subjects presented a disability worsening risk of 1.69 times (95%CI:1.11-2.57), ND/AO subjects showed a 2-fold increase in risk (95%CI:1.34-2.98), while being D/AO more than trebled the risk, even after considering confounding variables (HR:3.39,95%CI:1.91-6.02). Mortality risk after adjustment for other confounding variables was 1.57 (95%CI:1.16-2.13) for ND/AO and 2.46 (95%CI:1.34-4.52) for D/AO. CONCLUSIONS: Dynapenic abdominal obese subjects are at higher risk of worsening disability and mortality than subjects with dynapenia or central fat distribution only.

Mixed Nodule Infection in Sinorhizobium meliloti-Medicago sativa Symbiosis Suggest the Presence of Cheating Behavior.

In the symbiosis between rhizobia and legumes, host plants can form symbiotic root nodules with multiple rhizobial strains, potentially showing different symbiotic performances in nitrogen fixation. Here, we investigated the presence of mixed nodules, containing rhizobia with different degrees of mutualisms, and evaluate their relative fitness in the Sinorhizobium meliloti-Medicago sativa model symbiosis. We used three S. meliloti strains, the mutualist strains Rm1021 and BL225C and the non-mutualist AK83. We performed competition experiments involving both in vitro and in vivo symbiotic assays with M. sativa host plants. We show the occurrence of a high number (from 27 to 100%) of mixed nodules with no negative effect on both nitrogen fixation and plant growth. The estimation of the relative fitness as non-mutualist/mutualist ratios in single nodules shows that in some nodules the non-mutualist strain efficiently colonized root nodules along with the mutualist ones. In conclusion, we can support the hypothesis that in S. meliloti-M. sativa symbiosis mixed nodules are formed and allow non-mutualist or less-mutualist bacterial partners to be less or not sanctioned by the host plant, hence allowing a potential form of cheating behavior to be present in the nitrogen fixing symbiosis.

Dark fermentation, anaerobic digestion and microbial fuel cells: An integrated system to valorize swine manure and rice bran.

This work describes how dark fermentation (DF), anaerobic digestion (AD) and microbial fuel cells (MFC) and solid-liquid separation can be integrated to co-produce valuable biochemicals (hydrogen and methane), bioelectricity and biofertilizers. Two integrated systems (System 1: AD+MFC, and System 2: DF+AD+MFC) are described and compared to a traditional one-stage AD system in converting a mixture (COD=124±8.1gO2kg(-1)Fresh Matter) of swine manure and rice bran. System 1 gave a biomethane yield of 182 LCH4kg(-1)COD-added, while System 2 gave L yields of bio-hydrogen and bio-methane of 27.3±7.2LH2kg(-1)COD-added and 154±14LCH4kg(-1)COD-added, respectively. A solid-liquid separation (SLS) step was applied to the digested slurry, giving solid and liquid fractions. The liquid fraction was treated via the MFC-steps, showing power densities of 12-13Wm(-3) (500Ω) and average bioelectricity yields of 39.8Whkg(-1)COD to 54.2Whkg(-1)COD.

Correction: Barcoding Eophila crodabepis sp. nov. (Annelida, Oligochaeta, Lumbricidae), a Large Stripy Earthworm from Alpine Foothills of Northeastern Italy Similar to Eophila tellinii (Rosa, 1888).

[This corrects the article DOI: 10.1371/journal.pone.0151799.].

Barcoding Eophila crodabepis sp. nov. (Annelida, Oligochaeta, Lumbricidae), a Large Stripy Earthworm from Alpine Foothills of Northeastern Italy Similar to Eophila tellinii (Rosa, 1888).

A new Italian earthworm morphologically close to the similarly large and anecic Eophila tellinii (Rosa, 1888) is described. Distribution of Eophila crodabepis sp. nov. extends over 750 km2 from East to West on the Asiago Plateau and Vittorio Veneto Hills, from North to South on mounts Belluno Prealps (Praderadego and Cesen), Asiago, Grappa and onto the Montello foothills. This range abuts that of Eophila tellinii in northern Friuli Venezia Giulia region. Known localities of both E. tellinii and E. crodabepis sp. nov. are mapped. mtDNA barcoding definitively separates the new western species from classical Eophila tellinii (Rosa, 1888).

Quorum vs. diffusion sensing: a quantitative analysis of the relevance of absorbing or reflecting boundaries.

The consequences of the boundary conditions (signal reflecting vs. signal adsorbing) on bacterial intercellular communication were addressed by a combined physics and microbiology approach. A predictive biophysical model was devised that considered system size, diffusion from given points, signal molecule decay and boundary properties. The theoretical predictions were tested with two experimental agarose-gel-based set-ups for reflecting or absorbing boundaries. N-acyl homoserine lactone (AHL) concentration profiles were measured using the Agrobacterium tumefaciens NTL4 bioassay and found to agree with model predictions. The half-life of AHL was estimated to be 7 days. The absorbing vs. reflecting nature of the boundaries drastically changed AHL concentration profiles. The effect of a single nonreflecting boundary side was equivalent to a 100-fold lower cell concentration. Results suggest that the kinetics of signal accumulation vs. signal removal and their threshold-mediated phenotypic consequences are directly linked to the properties of biofilm boundaries, stressing the relevance of the diffusion sensing component in bacterial communication.

Microbiological features and bioactivity of a fermented manure product (preparation 500) used in biodynamic agriculture.

The fermented manure derivative known as Preparation 500 is traditionally used as a field spray in biodynamic agriculture for maintaining and increasing soil fertility. This work aimed at characterizing the product from a microbiological standpoint and at assaying its bioactive properties. The approach involved molecular taxonomical characterization of the culturable microbial community; ARISA fingerprints of the total bacteria and fungal communities; chemical elemental macronutrient analysis via a combustion analyzer; activity assays for six key enzymes; bioassays for bacterial quorum sensing and chitolipooligosaccharide production; and plant hormonelike activity. The material was found to harbor a bacterial community of 2.38 × 10(8) CFU/g dw dominated by Grampositives with minor instances of Actinobacteria and Gammaproteobacteria. ARISA showed a coherence of bacterial assemblages in different preparation lots of the same year in spite of geographic origin. Enzymatic activities showed elevated values of beta-glucosidase, alkaline phosphatase, chitinase, and esterase. The preparation had no quorum sensing-detectable signal, and no rhizobial nod gene-inducing properties, but displayed a strong auxin-like effect on plants. Enzymatic analyses indicated a bioactive potential in the fertility and nutrient cycling contexts. The IAA activity and microbial degradation products qualify for a possible activity as soil biostimulants. Quantitative details and possible modes of action are discussed.