Alien molluscs affect the composition and diversity of native macroinvertebrates in a sandy flat of Lake Neuchâtel,Switzerland

The spread of alien molluscs is a serious threat to native biodiversity in fresh waters. Alien freshwater molluscs may deplete the resources of native species and alter the physical structure of the habitat through their shell mass. These changes might have both positive and negative effects on native community members. We investigated the native macroinvertebrate community in relation to the densities of four alien mollusc species (Corbicula fluminea, Dreissena polymorpha, Potamopyrgus antipodarum and Lithoglyphus naticoides) in a sandy flat of Lake Neuchatel, Switzerland. The habitat examined was dominated by these alien mollusc species. The abundance of the alien molluscs did not directly impact the native community assembly. However, C. fluminea and D. polymorpha influenced the composition and diversity of native macroinvertebrates by transforming the sandy substratum into a partly hard substratum habitat. Substantial differences in community composition between shallow (<3.5 m) and (≥5 m) deep sites were recorded. At shallow sites, the abundance of D. polymorpha was significantly reduced as a result of depth-selective feeding of ducks. A controlled shell decay study revealed that shells of alien molluscs (C. fluminea, D. polymorpha) persist for a longer period in the sediment than those of native molluscs. Consequently, shells of alien molluscs have a long-lasting impact by modifying the sandy habitat. This form of ecosystem engineering favours the occurrence of several native taxa, but is disadvantageous for other taxa with specific habitat requirements, and thus can be regarded as an indirect impact of competition.     

Genome sequence of Weissella confusa LBAE C39-2, isolated from a wheat sourdough

Weissella confusa is a rod-shaped heterofermentative lactic acid bacterium from the family of Leuconostocaceae. Here we report the draft genome sequence of the strain W. confusa LBAE C39-2 isolated from a traditional French wheat sourdough.     

Digestive plasticity as a response to woodland fragmentation in roe deer

Digestive plasticity, which refers to changes in digestive features due to changes in both internal and external environmental conditions, is a crucial factor for understanding the ability of species to cope with environmental changes. In Europe, agricultural intensification and the loss of forests have been major challenges for original forest dwellers, however some species, such as the European roe deer (Capreolus capreolus), have been able to successfully colonize these new habitats. In this work, we investigated the adaptation of some digestive features of roe deer to the agricultural landscapes. We assessed whether changes in local landscape structure influenced the mass of both reticulorumen (RR) and distal fermentation chamber (DFC) of 47 juvenile and adult roe deer inhabiting an agro-ecosystem in southwest France. Woodland cover had a clear effect on diet quality (estimated by the rate of gas production of digestive contents) and DFC weight of animals. In fact, deer from the most forested landscapes showed heavier DFCs and fed on poorer quality diet (lower gas production) than their counterparts from the most open landscapes. RR mass was less influenced by the landscape openness, being the age of animals the main factor for understanding the variations of this digestive feature in our study area. We can conclude that colonizing agricultural landscapes increases the access to highly energetic and digestive resources.     

Milk ejection in mice LG/J x SM/J

In mammals, milk provision is crucial to offspring survival and growth from birth to weaning. Milk deficiency early in life may cause death or changes in the progeny metabolism that later may lead to obesity and metabolic disorders. This study investigates milk ejection (ME) the first day after birth (D1) in F₂ females from the intercross of LG/J and SM/J inbred mice strains. The absence of milk in F₃ pups?? stomach at D1 is directly associated with their survival (p?<?0.001) and growth pattern (p?<?0.001) in the early stages of life. Furthermore, late growth pattern is also affected by this lack of nutrients at D1 because pups that survive this absence, mostly males, are heavier at weaning (p?<?0.001) which, after necropsy, is shown to be due to significant higher total fat deposition (p?<?0.01). We performed QTL analysis for ME at D1 in these F₂ females. Maternal performance of ME revealed a complex genetic architecture which even though it contains only a single QTL (accounting for 8?% of the variation in ME), it is totally context-dependent on the genetic background. We discovered many regions involved in epistatic interactions that together with the single QTL explain 19?% of the genetic variation for this trait. Milk ejection is an important component of maternal care, and understanding the mechanisms modulating its variation, along with other maternal features, may help to disentangle the complexity that is the mother/offspring relationship.     

Reduced muscle carnosine content in type 2, but not in type 1 diabetic patients

Carnosine is present in high concentrations in skeletal muscle where it contributes to acid buffering and functions also as a natural protector against oxidative and carbonyl stress. Animal studies have shown an anti-diabetic effect of carnosine supplementation. High carnosinase activity, the carnosine degrading enzyme in serum, is a risk factor for diabetic complications in humans. The aim of the present study was to compare the muscle carnosine concentration in diabetic subjects to the level in non-diabetics. Type 1 and 2 diabetic patients and matched healthy controls (total n=58) were included in the study. Muscle carnosine content was evaluated by proton magnetic resonance spectroscopy (3 Tesla) in soleus and gastrocnemius. Significantly lower carnosine content (-45%) in gastrocnemius muscle, but not in soleus, was shown in type 2 diabetic patients compared with controls. No differences were observed in type 1 diabetic patients. Type II diabetic patients display a reduced muscular carnosine content. A reduction in muscle carnosine concentration may be partially associated with defective mechanisms against oxidative, glycative and carbonyl stress in muscle.     

In sickness and in health: the widespread application of creatine supplementation

There is an extensive and still growing body of the literature supporting the efficacy of creatine (Cr) supplementation. In sports, creatine has been recognized as the most effective nutritional supplement in enhancing exercise tolerance, muscle strength and lean body mass. From a clinical perspective, the application of Cr supplementation is indeed exciting. Evidences of benefits from this supplement have been reported in a broad range of diseases, including myopathies, neurodegenerative disorders, cancer, rheumatic diseases, and type 2 diabetes. In addition, after hundreds of published studies and millions of exposures creatine supplementation maintains an excellent safety profile. Thus, we contend that the widespread application of this supplement may benefit athletes, elderly people and various patient populations. In this narrative review, we aimed to summarize both the ergogenic and therapeutic effects of Cr supplementation. Furthermore, we reviewed the impact of Cr supplementation on kidney function.     

Evidences for a role of protein cross-links in transglutaminase-related disease

Transglutaminases (TGs) are a large family of related and ubiquitous enzymes that catalyze the cross-linking of a glutaminyl residue of a protein/peptide substrate to a lysyl residue of a protein/peptide co-substrate. Considerable and intense progress has been made in the understanding of the chemistry, molecular biology and cell biology of TGs. The knowledge that very different physiological and pathological processes are dependent on the presence of adequate levels of these cross-linking enzymes and on the amount of both free and protein-conjugated polyamines by TG, has generated an incredible amount of original research and review articles. It is clear that TG-mediated reactions are essential for some biological processes, such as blood coagulation, skin barrier formation and extracellular matrix assembly, but may also be involved in pathogenetic mechanisms responsible for several human diseases, such as cancer, AIDS, neurodegenerative disorders, celiac disease, and eye lens opacification. We present here a comprehensive review of recent insights into the pathophysiology of TGs related to their protein cross-linking activity.     

The highly dynamic CRISPR1 system of Streptococcus agalactiae controls the diversity of its mobilome

Clustered regularly interspaced short palindromic repeats (CRISPR) confer immunity against mobile genetic elements (MGEs) in prokaryotes. Streptococcus agalactiae, a leading cause of neonatal infections contains in its genome two CRISPR/Cas systems. We show that type 1‐C CRISPR2 is present in few strains but type 2‐A CRISPR1 is ubiquitous. Comparative sequence analysis of the CRISPR1 spacer content of 351 S. agalactiae strains revealed that it is extremely diverse due to the acquisition of new spacers, spacer duplications and spacer deletions that witness the dynamics of this system. The spacer content profile mirrors the S. agalactiae population structure. Transfer of a conjugative transposon targeted by CRISPR1 selected for spacer rearrangements, suggesting that deletions and duplications pre‐exist in the population. The comparison of protospacers located within MGE or the core genome and protospacer‐associated motif‐shuffling demonstrated that the GG motif is sufficient to discriminate self and non‐self and for spacer selection and integration. Strikingly more than 40% of the 949 different CRISPR1 spacers identified target MGEs found in S. agalactiae genomes. We thus propose that the S. agalactiae type II‐A CRISPR1/Cas system modulates the cohabitation of the species with its mobilome, as such contributing to the diversity of MGEs in the population.     

Diagnosis of deep‐seated lymphomas by endoscopic ultrasound‐guided fine needle aspiration combined with flow cytometry

A. Stacchini, P. Carucci, D. Pacchioni, G. Accinelli, A. Demurtas, S. Aliberti, M. Bosco, M. Bruno, A. Balbo Mussetto, M. Rizzetto, G. Bussolati and C. De Angelis
Diagnosis of deep‐seated lymphomas by endoscopic ultrasound‐guided fine needle aspiration combined with flow cytometry Objective: Although endoscopic ultrasound combined with fine needle aspiration (EUS‐FNA) is rapidly becoming the preferred diagnostic approach for the sampling and diagnosis of gastrointestinal and mediastinal malignancies, there are limited data as to its use in the diagnosis of lymphoproliferative disorders. Therefore, we carried out a retrospective evaluation of the performance of EUS‐guided FNA combined with flow cytometry (FC) as a tool to improve overall sensitivity and specificity in the diagnosis of lymphoma. Methods: Of 1560 patients having EUS‐guided FNA during the period of the study, a total of 56 patients were evaluated by cytology with FC after EUS‐FNA. There was adequate material to perform FC analysis for all but one case. Results: EUS‐FNA‐FC gave a diagnosis of lymphoma in 11 cases and of reactive lymphadenopathy in 20. A specific histological type was defined by FC alone in eight cases. The remaining cases were diagnosed later by cytology and cell block sections: 13 carcinomas, nine granulomatous lymphadenopathies and one mediastinal extramedullary haematopoiesis. One case was considered only suspicious for lymphoma on cytology and FC but was not confirmed on molecular analysis and one had insufficient material for FC. Conclusions: Our results show that a combination of EUS‐FNA‐FC is a feasible and highly accurate method, which may be used for the diagnosis and subtyping of deep‐seated lymphoma, providing a significant improvement to cytomorphology alone both for diagnosis and treatment planning, as long as immunocytochemistry is available for non‐lymphoma cases.