58 research outputs found
NUEVA ESPECIE DE SALAMANDRA DEL GÉNERO PSEUDOEURYCEA (AMPHIBIA: CAUDATA: PLETHODONTIDAE) DE LA REGIÓN AMUZGA, AL SURESTE DE GUERRERO, MÉXICO
A new species of plethodontid salamander of the genus Pseudoeurycea from the Sierra de Malinaltepec at Guerrero is described here. P. amuzga is recognized by morphological and ecological features, and coloration, from related species of the Sierra Madre del Sur in Guerrero and Oaxaca, México.Se describe una especie nueva de salamandra del género Pseudoeurycea de la Sierra de Malinaltepec, al sureste del estado de Guerrero. P. amuzga difiere al nivel morfológico, de coloración y ecológico de sus congéneres de la región central de la Sierra Madre del Sur en Guerrero y Oaxaca, México
From functional diversity to human well-being: A conceptual framework for agroecosystem sustainability
[EN] CONTEXT: Agricultural intensification contributes to global food security and well-being by supplying the food demand of a growing human population. However, ongoing land-use change and intensification seriously affect the abundance, diversity and distribution of species, besides many other impacts, thereby threatening the functioning of ecosystems worldwide. Despite the accumulating evidence that the current agricultural model is unsustainable, we are far from understanding the consequences of functional diversity loss for functioning and ecosystem service supply and the potential long-term threats to food security and human well-being.
OBJECTIVE: In this review, we propose a conceptual framework to understand the relationships between functional diversity and human well-being that also considers agroecosystem health. To this end, we identify the most commonly assumed relationships linking functional diversity to regulating and provisioning agroecosystem services and their importance for human well-being, emphasising the most serious knowledge gaps in the in-dividual pathways of the conceptual framework.
METHODS: A consortium formed by an international panel of experts from different disciplines including functional diversity, ecosystem services and human health compiled 275 articles. Members of the consortium proposed literature to exemplify each specific aspect of the conceptual framework in the text, in accordance with his/her field of expertise. The guideline for all experts was to focus mostly in current literature (38% of the references are from the last 5 years and 66% from the last decade), with special interest in reviews and synthesis articles (42% of the references), as well as meta-analyses and global studies (10% of the references).
RESULTS AND CONCLUSIONS: The factors that influence agroecosystem health are extremely complex, involving both services and disservices related to land-use management and environmental conditions. The global human population needs sustainable and resilient agroecosystems and a concerted effort is needed to fundamentally redesign agricultural practices to feed the growing human population without further jeopardising the quality of life for future generations. We highlight the potential effects of land-use change and ecological intensification on the functional diversity of plant and animal communities, and the resulting consequences for ecosystem services and ultimately human health.
SIGNIFICANCE: The resulting conceptual model is developed for researchers as well as policy makers high- lighting the need for a holistic approach to understand diversity impacts on human well-being. Finally, we document a major knowledge gap due to the lack of any studies focusing on the full pathway from diversity to human well-being.S
The Clostridium difficile Cell Wall Protein CwpV is Antigenically Variable between Strains, but Exhibits Conserved Aggregation-Promoting Function
Clostridium difficile is the main cause of antibiotic-associated diarrhea, leading to significant morbidity and mortality and putting considerable economic pressure on healthcare systems. Current knowledge of the molecular basis of pathogenesis is limited primarily to the activities and regulation of two major toxins. In contrast, little is known of mechanisms used in colonization of the enteric system. C. difficile expresses a proteinaceous array on its cell surface known as the S-layer, consisting primarily of the major S-layer protein SlpA and a family of SlpA homologues, the cell wall protein (CWP) family. CwpV is the largest member of this family and is expressed in a phase variable manner. Here we show CwpV promotes C. difficile aggregation, mediated by the C-terminal repetitive domain. This domain varies markedly between strains; five distinct repeat types were identified and were shown to be antigenically distinct. Other aspects of CwpV are, however, conserved. All CwpV types are expressed in a phase variable manner. Using targeted gene knock-out, we show that a single site-specific recombinase RecV is required for CwpV phase variation. CwpV is post-translationally cleaved at a conserved site leading to formation of a complex of cleavage products. The highly conserved N-terminus anchors the CwpV complex to the cell surface. Therefore CwpV function, regulation and processing are highly conserved across C. difficile strains, whilst the functional domain exists in at least five antigenically distinct forms. This hints at a complex evolutionary history for CwpV
Effect of RNS60 in amyotrophic lateral sclerosis: a phase II multicentre, randomized, double-blind, placebo-controlled trial
Background and purpose Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with limited treatment options. RNS60 is an immunomodulatory and neuroprotective investigational product that has shown efficacy in animal models of ALS and other neurodegenerative diseases. Its administration has been safe and well tolerated in ALS subjects in previous early phase trials. Methods This was a phase II, multicentre, randomized, double-blind, placebo-controlled, parallel-group trial. Participants diagnosed with definite, probable or probable laboratory-supported ALS were assigned to receive RNS60 or placebo administered for 24 weeks intravenously (375 ml) once a week and via nebulization (4 ml/day) on non-infusion days, followed by an additional 24 weeks off-treatment. The primary objective was to measure the effects of RNS60 treatment on selected biomarkers of inflammation and neurodegeneration in peripheral blood. Secondary objectives were to measure the effect of RNS60 on functional impairment (ALS Functional Rating Scale-Revised), a measure of self-sufficiency, respiratory function (forced vital capacity, FVC), quality of life (ALS Assessment Questionnaire-40, ALSAQ-40) and survival. Tolerability and safety were assessed. Results Seventy-four participants were assigned to RNS60 and 73 to placebo. Assessed biomarkers did not differ between arms. The mean rate of decline in FVC and the eating and drinking domain of ALSAQ-40 was slower in the RNS60 arm (FVC, difference 0.41 per week, standard error 0.16, p = 0.0101; ALSAQ-40, difference -0.19 per week, standard error 0.10, p = 0.0319). Adverse events were similar in the two arms. In a post hoc analysis, neurofilament light chain increased over time in bulbar onset placebo participants whilst remaining stable in those treated with RNS60. Conclusions The positive effects of RNS60 on selected measures of respiratory and bulbar function warrant further investigation
Withdrawal of mechanical ventilation in amyotrophic lateral sclerosis patients: a multicenter Italian survey
Background: Law 219/2017 was approved in Italy in December 2017, after a years-long debate on the autonomy of healthcare choices. This Law, for the first time in Italian legislation, guarantees the patient's right to request for withdrawal of life-sustaining treatments, including mechanical ventilation (MV). Objective: To investigate the current status of MV withdrawal in amyotrophic lateral sclerosis (ALS) patients in Italy and to assess the impact of Law 219/2017 on this practice. Methods: We conducted a Web-based survey, addressed to Italian neurologists with expertise in ALS care, and members of the Motor Neuron Disease Study Group of the Italian Society of Neurology. Results: Out of 40 ALS Italian centers, 34 (85.0%) responded to the survey. Law 219/2017 was followed by an increasing trend in MV withdrawals, and a significant increase of neurologists involved in this procedure (p 0.004). However, variations across Italian ALS centers were observed, regarding the inconsistent involvement of community health services and palliative care (PC) services, and the intervention and composition of the multidisciplinary team. Conclusions: Law 219/2017 has had a positive impact on the practice of MV withdrawal in ALS patients in Italy. The recent growing public attention on end-of-life care choices, along with the cultural and social changes in Italy, requires further regulatory frameworks that strengthen tools for self-determination, increased investment of resources in community and PC health services, and practical recommendations and guidelines for health workers involved
Molecular Mechanisms Generating and Stabilizing Terminal 22q13 Deletions in 44 Subjects with Phelan/McDermid Syndrome
In this study, we used deletions at 22q13, which represent a substantial source of human pathology (Phelan/McDermid syndrome), as a model for investigating the molecular mechanisms of terminal deletions that are currently poorly understood. We characterized at the molecular level the genomic rearrangement in 44 unrelated patients with 22q13 monosomy resulting from simple terminal deletions (72%), ring chromosomes (14%), and unbalanced translocations (7%). We also discovered interstitial deletions between 17–74 kb in 9% of the patients. Haploinsufficiency of the SHANK3 gene, confirmed in all rearrangements, is very likely the cause of the major neurological features associated with PMS. SHANK3 mutations can also result in language and/or social interaction disabilities. We determined the breakpoint junctions in 29 cases, providing a realistic snapshot of the variety of mechanisms driving non-recurrent deletion and repair at chromosome ends. De novo telomere synthesis and telomere capture are used to repair terminal deletions; non-homologous end-joining or microhomology-mediated break-induced replication is probably involved in ring 22 formation and translocations; non-homologous end-joining and fork stalling and template switching prevail in cases with interstitial 22q13.3. For the first time, we also demonstrated that distinct stabilizing events of the same terminal deletion can occur in different early embryonic cells, proving that terminal deletions can be repaired by multistep healing events and supporting the recent hypothesis that rare pathogenic germline rearrangements may have mitotic origin. Finally, the progressive clinical deterioration observed throughout the longitudinal medical history of three subjects over forty years supports the hypothesis of a role for SHANK3 haploinsufficiency in neurological deterioration, in addition to its involvement in the neurobehavioral phenotype of PMS
Burden of disease attributable to risk factors in European countries: a scoping literature review
Objectives: Within the framework of the burden of disease (BoD) approach, disease, and injury burden estimates attributable to risk factors are a useful guide for policy formulation and priority setting in disease prevention. Considering the important differences in methods, and their impact on burden estimates, we conducted a scoping literature review to: (1) map the BoD assessments including risk factors performed across Europe, and (2) identify the methodological choices in comparative risk assessment (CRA) and risk assessment methods. Methods: We searched multiple literature databases, including grey literature websites, and targeted public health agencies' websites. Results: A total of 113 studies were included in the synthesis and further divided into independent BoD assessments (54 studies) and studies linked to the Global Burden of Disease (59 papers). Our results showed that the methods used to perform CRA varied substantially across independent European BoD studies. While there were some methodological choices that were more common than others, we did not observe patterns in terms of country, year, or risk factor. Each methodological choice can affect the comparability of estimates between and within countries and/or risk factors since they might significantly influence the quantification of the attributable burden. From our analysis, we observed that the use of CRA was less common for some types of risk factors and outcomes. These included environmental and occupational risk factors, which are more likely to use bottom-up approaches for health outcomes where disease envelopes may not be available. Conclusions: Our review also highlighted misreporting, the lack of uncertainty analysis, and the under-investigation of causal relationships in BoD studies. Development and use of guidelines for performing and reporting BoD studies will help understand differences, and avoid misinterpretations thus improving comparability among estimates.info:eu-repo/semantics/publishedVersio
Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences
The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported
by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on
18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based
researchers who signed it in the short time span from 20 September to 6 October 2016
An explainable model of host genetic interactions linked to COVID-19 severity
We employed a multifaceted computational strategy to identify the genetic factors contributing to increased risk of severe COVID-19 infection from a Whole Exome Sequencing (WES) dataset of a cohort of 2000 Italian patients. We coupled a stratified k-fold screening, to rank variants more associated with severity, with the training of multiple supervised classifiers, to predict severity based on screened features. Feature importance analysis from tree-based models allowed us to identify 16 variants with the highest support which, together with age and gender covariates, were found to be most predictive of COVID-19 severity. When tested on a follow-up cohort, our ensemble of models predicted severity with high accuracy (ACC = 81.88%; AUCROC = 96%; MCC = 61.55%). Our model recapitulated a vast literature of emerging molecular mechanisms and genetic factors linked to COVID-19 response and extends previous landmark Genome-Wide Association Studies (GWAS). It revealed a network of interplaying genetic signatures converging on established immune system and inflammatory processes linked to viral infection response. It also identified additional processes cross-talking with immune pathways, such as GPCR signaling, which might offer additional opportunities for therapeutic intervention and patient stratification. Publicly available PheWAS datasets revealed that several variants were significantly associated with phenotypic traits such as "Respiratory or thoracic disease", supporting their link with COVID-19 severity outcome.A multifaceted computational strategy identifies 16 genetic variants contributing to increased risk of severe COVID-19 infection from a Whole Exome Sequencing dataset of a cohort of Italian patients
Peri-operative red blood cell transfusion in neonates and infants: NEonate and Children audiT of Anaesthesia pRactice IN Europe: A prospective European multicentre observational study
BACKGROUND: Little is known about current clinical practice concerning peri-operative red blood cell transfusion in neonates and small infants. Guidelines suggest transfusions based on haemoglobin thresholds ranging from 8.5 to 12 g dl-1, distinguishing between children from birth to day 7 (week 1), from day 8 to day 14 (week 2) or from day 15 (≥week 3) onwards. OBJECTIVE: To observe peri-operative red blood cell transfusion practice according to guidelines in relation to patient outcome. DESIGN: A multicentre observational study. SETTING: The NEonate-Children sTudy of Anaesthesia pRactice IN Europe (NECTARINE) trial recruited patients up to 60 weeks' postmenstrual age undergoing anaesthesia for surgical or diagnostic procedures from 165 centres in 31 European countries between March 2016 and January 2017. PATIENTS: The data included 5609 patients undergoing 6542 procedures. Inclusion criteria was a peri-operative red blood cell transfusion. MAIN OUTCOME MEASURES: The primary endpoint was the haemoglobin level triggering a transfusion for neonates in week 1, week 2 and week 3. Secondary endpoints were transfusion volumes, 'delta haemoglobin' (preprocedure - transfusion-triggering) and 30-day and 90-day morbidity and mortality. RESULTS: Peri-operative red blood cell transfusions were recorded during 447 procedures (6.9%). The median haemoglobin levels triggering a transfusion were 9.6 [IQR 8.7 to 10.9] g dl-1 for neonates in week 1, 9.6 [7.7 to 10.4] g dl-1 in week 2 and 8.0 [7.3 to 9.0] g dl-1 in week 3. The median transfusion volume was 17.1 [11.1 to 26.4] ml kg-1 with a median delta haemoglobin of 1.8 [0.0 to 3.6] g dl-1. Thirty-day morbidity was 47.8% with an overall mortality of 11.3%. CONCLUSIONS: Results indicate lower transfusion-triggering haemoglobin thresholds in clinical practice than suggested by current guidelines. The high morbidity and mortality of this NECTARINE sub-cohort calls for investigative action and evidence-based guidelines addressing peri-operative red blood cell transfusions strategies. TRIAL REGISTRATION: ClinicalTrials.gov, identifier: NCT02350348
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