Increasing aridity reduces soil microbial diversity and abundance in global drylands.

Soil bacteria and fungi play key roles in the functioning of terrestrial ecosystems, yet our understanding of their responses to climate change lags significantly behind that of other organisms. This gap in our understanding is particularly true for drylands, which occupy ∼41% of Earth´s surface, because no global, systematic assessments of the joint diversity of soil bacteria and fungi have been conducted in these environments to date. Here we present results from a study conducted across 80 dryland sites from all continents, except Antarctica, to assess how changes in aridity affect the composition, abundance, and diversity of soil bacteria and fungi. The diversity and abundance of soil bacteria and fungi was reduced as aridity increased. These results were largely driven by the negative impacts of aridity on soil organic carbon content, which positively affected the abundance and diversity of both bacteria and fungi. Aridity promoted shifts in the composition of soil bacteria, with increases in the relative abundance of Chloroflexi and α-Proteobacteria and decreases in Acidobacteria and Verrucomicrobia. Contrary to what has been reported by previous continental and global-scale studies, soil pH was not a major driver of bacterial diversity, and fungal communities were dominated by Ascomycota. Our results fill a critical gap in our understanding of soil microbial communities in terrestrial ecosystems. They suggest that changes in aridity, such as those predicted by climate-change models, may reduce microbial abundance and diversity, a response that will likely impact the provision of key ecosystem services by global drylands.

A novel interstitial deletion of 2q22.3 q23.3 in a patient with dysmorphic features, epilepsy, aganglionosis, pure red cell aplasia, and skeletal malformations.

Many chromosomal deletions encompassing the 2q23.1 region have been described ranging from small deletions of 38 kb up to >19 Mb. Most phenotypic features of the 2q23.1 deletion syndrome are due to a MBD5 gene loss independent of the size of the deletion. Here, we describe a male patient harboring a novel interstitial deletion encompassing the 2q22.3 q23.3 chromosomal region. Array-CGH revealed a 7.1 Mb deletion causing haploinsufficiency of several genes including MBD5, ACVR2, KIF5C, and EPC2. This patient presents with additional findings to those already described in individuals who have deletions of MBD5 including toes absence of halluces, pure red cell aplasia, and intestinal aganglionosis. Interestingly, in the deleted region there are previously identified regulatory sequences which are located upstream to ZEB2, which is associated with Hirschsprung disease (HSCR). Several genes have been associated with pure red cell aplasia, but to our knowledge, this is the first time that 2q deletion is associated with this phenotype. These additional findings should be added to the list of manifestations associated with 2q deletion, and provide support for the hypothesis that this individual has a true contiguous gene deletion syndrome.

Decoupling of soil nutrient cycles as a function of aridity in global drylands.

The biogeochemical cycles of carbon (C), nitrogen (N) and phosphorus (P) are interlinked by primary production, respiration and decomposition in terrestrial ecosystems. It has been suggested that the C, N and P cycles could become uncoupled under rapid climate change because of the different degrees of control exerted on the supply of these elements by biological and geochemical processes. Climatic controls on biogeochemical cycles are particularly relevant in arid, semi-arid and dry sub-humid ecosystems (drylands) because their biological activity is mainly driven by water availability. The increase in aridity predicted for the twenty-first century in many drylands worldwide may therefore threaten the balance between these cycles, differentially affecting the availability of essential nutrients. Here we evaluate how aridity affects the balance between C, N and P in soils collected from 224 dryland sites from all continents except Antarctica. We find a negative effect of aridity on the concentration of soil organic C and total N, but a positive effect on the concentration of inorganic P. Aridity is negatively related to plant cover, which may favour the dominance of physical processes such as rock weathering, a major source of P to ecosystems, over biological processes that provide more C and N, such as litter decomposition. Our findings suggest that any predicted increase in aridity with climate change will probably reduce the concentrations of N and C in global drylands, but increase that of P. These changes would uncouple the C, N and P cycles in drylands and could negatively affect the provision of key services provided by these ecosystems.

A novel homozygous mutation at the GAA gene in Mexicans with early-onset Pompe disease.

Glycogen-storage disease type II, also named Pompe disease, is caused by the deficiency of the enzyme acid alpha-glucosidase, which originates lysosomal glycogen accumulation leading to progressive neuromuscular damage. Early-onset Pompe disease shows a debilitating and frequently fulminating course. To date, more than 300 mutations have been described; the majority of them are unique to each affected individual. Most early-onset phenotypes are associated with frameshift mutations leading to a truncated alpha-glucosidase protein with loss of function. Founder effects are responsible from many cases from few highprevalence world regions. Herein we described two apparently unrelated cases affected with classical early-onset Pompe disease, both pertaining to a small region from Central Mexico (the State of San Luis Potosí), the same novel homozygous frameshift mutation at gene GAA (c.1987delC) was demonstrated in both cases. This GAA gene deletion implies a change of glutamine to serine at codon 663, and a new reading frame that ends after 33 base pairs, which leads to the translation of a truncated protein. This report contributes to widen the knowledge on the effect of pathogenic mutations in Pompe disease. Here we postulate the existence of a founder effect.

Intima media thickness in children undergoing dialysis.

BACKGROUND: Uremic vasculopathy, including vascular calcification, increases the risk for cardiovascular disease and mortality in chronic kidney disease (CKD) patients. We have investigated the prevalence and factors associated with vasculopathy in children undergoing peritoneal dialysis (PD) or hemodialysis (HD) in a single center. METHODS: Common carotid intima media thickness (cIMT) and its relation with demographics, biochemical parameters and medication was analyzed in 60 patients (mean age 12.9 ± 3.4 years; 27 girls) treated with PD (n = 31) or HD (n = 29) for 34 ± 34 months. Patients were divided into two groups: normal cIMT and increased cIMT. RESULTS: Mean levels of calcium, phosphate and calcium/phosphate product were in the normal range, the but parathyroid hormone level, 729 ± 670 pg/mL, was higher than the National Kidney Foundation Kidney Disease Outcome Quality Iniative (K/DOQI) recommendations. Twenty-nine patients had increased cIMT, which was associated with time on dialysis of >2 years, hypercalcemia, higher daily dose of calcitriol and HD (vs. PD). In the multivariate analysis, accounting for time on dialysis, HD persisted as a risk for increased cIMT. CONCLUSIONS: The prevalence of increased cIMT in children on dialysis is similar to that reported in adults with CKD and increased with time on dialysis. HD was associated with increased cIMT, independently of time on dialysis; however, the results should be interpreted with caution due to the possible impact of confounding factors. These results underline the need to monitor and, if possible, prevent and treat increased cIMT in children on dialysis.

Extrusion and Low-Dose Irradiation Effects on Destruction of Clostridium sporogenes Spores in a Beef-Based Product.

The effects of extrusion cooking alone or in combination with electron beam radiation (3.5 kGy) on vacuum-packaged beef-based snack sticks containing beef cardiac muscle were investigated. During formulation, Clostridium sporogenes PA 3679 spores were added to achieve a concentration of 4 log CFU/g. Twin-screw extrusion cooking at 72°C reduced aerobic plate counts (APCs) by 3.63 log cycles and C. sporogenes viable cell counts by 2.02 log cycles for the inoculated product. After irradiation (3.5 kGy), APCs were decreased to 1 log CFU/g when compared to 0 kGy counterparts receiving 0 kGy. Spores were not detected in irradiated inoculated samples, which contained C. sporogenes PA 3679 at levels of 3.17 to 3.50 log CFU/g after extrusion cooking.

Gluconic Acid as a Fresh Beef Decontaminant.

Effectiveness of 0, 1.5 and 3.0% gluconic acid (G) and/or 0 and 1.5% lactic acid (L) solutions in reducing aerobic psychrotrophic bacteria plate counts (PPCs) and lactic acid bacteria counts (LACs) on vacuum-packaged beef was investigated at 0, 14, 28 and 56 days of storage. Instrumental and visual color changes were evaluated up to 28 days. Steaks treated with 1.5% L, plus 1.5% G or 3.0% G, solutions showed 2.0 and 2.5 log reductions (P<0.05) in PPCs compared to nontreated samples, respectively, at days 28 and 56. At 1.5%, G or L intervention for 0 and 14 days PPCs did not differ (P>0.05). However, PPCs were lower (P

Aroma Profile of Subprimals From Beef Carcasses Decontaminated With Chlorine and Lactic Acid.

Aroma notes of chuck rolls from decontaminated beef carcasses were evaluated. Carcasses were spray-treated with either water, 200 ppm chlorine or 3% lactic acid immediately after inspection and again after spray chilling. Following fabrication, each chuck roll was divided into four pieces; vacuum-packaged; and stored for 10, 40, 80 or 120 days at 4°C. At different storage times, a six-member, professional, sensory panel evaluated beefy, bloody, sour, grassy, spoiled and metallic aromatic impressions on cooked patties made from ground chuck roll pieces using a 15-point attribute scale. Psychrotrophic bacterial counts were conducted on raw, ground samples. Principal component statistical analysis showed that the first principal component described 96% of the data and, therefore, it was used as an average acceptability score that explained all aroma descriptors. Chucks from chlorine-treated carcasses tended to have higher (P = 0.08) acceptability scores, followed by lactic acid - and water-treated counterparts. The rate of change in aroma occurred faster between 10 and 40 days for lactic acid - and water-treated samples and between 40 and 80 days for chlorine-treated samples. Bacterial counts increased during storage up to 80 days; however, treatments were not different (P >0.05).