509 research outputs found
Crosstalk between the serine/threonine kinase StkP and the response regulator ComE controls the stress response and intracellular survival of Streptococcus pneumoniae
Streptococcus pneumoniae is an opportunistic human bacterial pathogen that usually colonizes the upper respiratory tract, but the invasion and survival mechanism in respiratory epithelial cells remains elusive. Previously, we described that acidic stress-induced lysis (ASIL) and intracellular survival are controlled by ComE through a yet unknown activation mechanism under acidic conditions, which is independent of the ComD histidine kinase that activates this response regulator for competence development at pH 7.8. Here, we demonstrate that the serine/threonine kinase StkP is essential for ASIL, and show that StkP phosphorylates ComE at Thr128. Molecular dynamic simulations predicted that Thr128-phosphorylation induces conformational changes on ComE’s DNA-binding domain. Using nonphosphorylatable (ComET128A) and phosphomimetic (ComET128E) proteins, we confirmed that Thr128-phosphorylation increased the DNA-binding affinity of ComE. The non-phosphorylated form of ComE interacted more strongly with StkP than the phosphomimetic form at acidic pH, suggesting that pH facilitated crosstalk. To identify the ComE-regulated genes under acidic conditions, a comparative transcriptomic analysis was performed between the comET128Aand wt strains, and differential expression of 104 genes involved in different cellular processes was detected, suggesting that the StkP/ComE pathway induced global changes in response to acidic stress. In the comET128Amutant, the repression of spxB and sodA correlated with decreased H2O2production, whereas the reduced expression of murN correlated with an increased resistance to cell wall antibiotic-induced lysis, compatible with cell wall alterations. In the comET128Amutant, ASIL was blocked and acid tolerance response was higher compared to the wt strain. These phenotypes, accompanied with low H2O2production,are likely responsible for the increased survival in pneumocytes of the comET128Amutant. We propose that the StkP/ComE pathway controls the stress response, thus affecting the intracellular survival of S. pneumoniae in pneumocytes, one of the first barriers that this pathogen must cross to establish an infection.Fil: Piñas, German Eduardo. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; ArgentinaFil: Reinoso Vizcaino, Nicolas Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica; ArgentinaFil: Yandar Barahona, Nubia Yadira. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica; ArgentinaFil: Cortes, Paulo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica; ArgentinaFil: Duran, Rosario. Instituto Pasteur de Montevideo; Uruguay. Instituto de Investigaciones Biológicas "Clemente Estable"; UruguayFil: Badapanda, Chandan. Xcelris Lab Limited; IndiaFil: Rathore, Ankita. Xcelris Lab Limited; IndiaFil: Bichara, Darío Román. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Cian, Melina Beatriz. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; ArgentinaFil: Olivero, Nadia Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica; ArgentinaFil: Perez, Daniel R.. University of Georgia; Estados UnidosFil: Echenique, Jose Ricardo. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentin
Cribado de Citomegalovirus en mujeres embarazadas
Introduction: Cytomegalovirus (CMV) is a DNA virus of the family Herpesviridae, constitutes one of the main causes of congenital infections in the world, the overall prevalence of births in developed countries is 0.64% and the incidence of 1% -7%. The rate of acquisition of CMV in pregnant women is 2% per year, in the medium-high socioeconomic level and 6% at lower levels. The susceptibility is greater in African-American and Hispanic women. The risk ofmaternal-fetal transmission increases with advancing gestational age, also (30-40%) depends on maternal primary infection both seroconversion and in the revival (1-2%), highlighting that the pre-existing maternal immunity not prevent intrauterine transmission or the development of the disease.
Objective: To evaluate the frequency of Cytomegalovirus infection in pregnant women.
Material and methods: a study of non-experimental, observational -cross in the pro-life basic Hospital, of the city of Latacunga,Ecuador. Analyzed 981 results of screening for IgG and IgM for CMV, pregnant womages between 14 and 45 years who were enrolled in the first trimester of pregnancy, the period between January 1, 2013 to December 31, 2016. Descriptive statistical methods were used.
Results: IgG positive was 95.7% and no positive result for IgM.
Conclusions: We cannot support universal screening for CMV, by the low prevalence of infection.Introducción: El citomegalovirus(CMV)es un ADN virus, de la familia Herpesviridae, constituye una de las principales causas de infecciones congénitas en el mundo, la prevalencia general de nacimientos en países desarrollados es de 0,64% y la incidencia del 1% -7%. La tasa de adquisición de CMV en mujeres embarazadas es de 2% anual,en el nivel socioeconómico medio-alto y 6% en niveles más bajos. La susceptibilidad es mayor en mujeres afroamericanas e hispanas. El riesgo de transmisión materno-fetalseincrementa con el avance de la edad gestacional, además depende de la seroconversión materna tanto en la primoinfección (30-40%) como en la reactivación (1-2%), poniendo en evidencia que la inmunidad materna preexistente no previene la transmisión intrauterina o el desarrollo de la enfermedad.
Objetivo: Evaluar la frecuencia deinfección por Citomegalovirus en mujeres embarazadas.
Material y métodos: Se realizó un estudio no experimental, observacional –transversal en el Hospital Básico PROVIDA, de la cuidad de Latacunga, Ecuador. Se analizaron 981 resultados de screening de IgG e IgM para CMV, de mujeres gestantes en edades entre 14 y 45 años que cursaban el primer trimestre de embarazo, del periodo comprendido entre el 1 de enero de 2013 al 31 de diciembre de 2016.Se utilizaron métodos estadísticos descriptivos.
Resultados: La IgG fue positiva el 95,7% y ningún resultado positivo para IgM.
Conclusiones: No podemos apoyar el cribado universal de CMV, por la baja prevalencia de primoinfeccion
Cribado de Citomegalovirus en mujeres embarazadas
Introduction: Cytomegalovirus (CMV) is a DNA virus of the family Herpesviridae, constitutes one of the main causes of congenital infections in the world, the overall prevalence of births in developed countries is 0.64% and the incidence of 1% -7%. The rate of acquisition of CMV in pregnant women is 2% per year, in the medium-high socioeconomic level and 6% at lower levels. The susceptibility is greater in African-American and Hispanic women. The risk ofmaternal-fetal transmission increases with advancing gestational age, also (30-40%) depends on maternal primary infection both seroconversion and in the revival (1-2%), highlighting that the pre-existing maternal immunity not prevent intrauterine transmission or the development of the disease.
Objective: To evaluate the frequency of Cytomegalovirus infection in pregnant women.
Material and methods: a study of non-experimental, observational -cross in the pro-life basic Hospital, of the city of Latacunga,Ecuador. Analyzed 981 results of screening for IgG and IgM for CMV, pregnant womages between 14 and 45 years who were enrolled in the first trimester of pregnancy, the period between January 1, 2013 to December 31, 2016. Descriptive statistical methods were used.
Results: IgG positive was 95.7% and no positive result for IgM.
Conclusions: We cannot support universal screening for CMV, by the low prevalence of infection.Introducción: El citomegalovirus(CMV)es un ADN virus, de la familia Herpesviridae, constituye una de las principales causas de infecciones congénitas en el mundo, la prevalencia general de nacimientos en países desarrollados es de 0,64% y la incidencia del 1% -7%. La tasa de adquisición de CMV en mujeres embarazadas es de 2% anual,en el nivel socioeconómico medio-alto y 6% en niveles más bajos. La susceptibilidad es mayor en mujeres afroamericanas e hispanas. El riesgo de transmisión materno-fetalseincrementa con el avance de la edad gestacional, además depende de la seroconversión materna tanto en la primoinfección (30-40%) como en la reactivación (1-2%), poniendo en evidencia que la inmunidad materna preexistente no previene la transmisión intrauterina o el desarrollo de la enfermedad.
Objetivo: Evaluar la frecuencia deinfección por Citomegalovirus en mujeres embarazadas.
Material y métodos: Se realizó un estudio no experimental, observacional –transversal en el Hospital Básico PROVIDA, de la cuidad de Latacunga, Ecuador. Se analizaron 981 resultados de screening de IgG e IgM para CMV, de mujeres gestantes en edades entre 14 y 45 años que cursaban el primer trimestre de embarazo, del periodo comprendido entre el 1 de enero de 2013 al 31 de diciembre de 2016.Se utilizaron métodos estadísticos descriptivos.
Resultados: La IgG fue positiva el 95,7% y ningún resultado positivo para IgM.
Conclusiones: No podemos apoyar el cribado universal de CMV, por la baja prevalencia de primoinfeccion
Direct evidence for flat bands in twisted bilayer graphene from nano-ARPES
Transport experiments in twisted bilayer graphene revealed multiple
superconducting domes separated by correlated insulating states. These
properties are generally associated with strongly correlated states in a flat
mini-band of the hexagonal moir\'e superlattice as it was predicted by band
structure calculations. Evidence for such a flat band comes from local
tunneling spectroscopy and electronic compressibility measurements, reporting
two or more sharp peaks in the density of states that may be associated with
closely spaced van Hove singularities. Direct momentum resolved measurements
proved difficult though. Here, we combine different imaging techniques and
angle resolved photoemission with simultaneous real and momentum space
resolution (nano-ARPES) to directly map the band dispersion in twisted bilayer
graphene devices near charge neutrality. Our experiments reveal large areas
with homogeneous twist angle that support a flat band with spectral weight that
is highly localized in momentum space. The flat band is separated from the
dispersive Dirac bands which show multiple moir\'e hybridization gaps. These
data establish the salient features of the twisted bilayer graphene band
structure.Comment: Submitted to Nature Materials. Nat. Phys. (2020
Cost analysis of skeletal-related events in Spanish patients with bone metastases from solid tumours
To estimate the cost per skeletal-related event (SRE) in patients with bone metastases secondary to solid tumours in the Spanish healthcare setting.
METHODS:
Patients diagnosed with bone metastases secondary to breast, prostate or lung cancer were included in this multicentre, observational study. SREs are defined as pathologic fracture (vertebral and non-vertebral fracture), radiation to bone, spinal cord compression or surgery to bone. Health resource utilisation associated with these events (inpatient stays, outpatient, emergency room and home health visits, nursing home stays and procedures) were collected retrospectively for all SREs that occurred in the 97 days prior to enrolment and prospectively during follow-up. Unit costs were obtained from the 2010 eSalud healthcare costs database.
RESULTS:
A total of 93 Spanish patients with solid tumours were included (31 had breast cancer, 21 prostate cancer and 41 lung cancer), contributing a total of 143 SREs to this cost analysis. Inpatient stays (between 9.0 and 29.9 days of mean length of stay per inpatient stay by SRE type) and outpatient visits (between 1.7 and 6.4 mean visits per SRE type) were the most frequently reported types of health resources utilised. The mean cost per SRE was between 2,377.79 (radiation to bone) and 7,902.62 (spinal cord compression).
CONCLUSION:
SREs are associated with a significant consumption of healthcare resources that generate a substantial economic burden for the Spanish healthcare system
Advance in the conceptual design of the European DEMO magnet system
The European DEMO, i.e. the demonstration fusion power plant designed in the framework of the Roadmap to Fusion Electricity by the EUROfusion Consortium, is approaching the end of the pre-conceptual design phase, to be accomplished with a Gate Review in 2020, in which all DEMO subsystems will be reviewed by panels of independent experts. The latest 2018 DEMO baseline has major and minor radius of 9.1 m and 2.9 m, plasma current 17.9 MA, toroidal field on the plasma axis 5.2 T, and the peak field in the toroidal-field (TF) conductor 12.0 T. The 900 ton heavy TF coil is prepared in four lowerature-superconductor (LTS) variants, some of them differing slightly, other significantly, from the ITER TF coil design. Two variants of the CS coils are investigated - a purely LTS one resembling the ITER CS, and a hybrid coil, in which the innermost layers made of HTS allow the designers either to increase the magnetic flux, and thus the duration of the fusion pulse, or to reduce the outer radius of the CS coil. An issue presently investigated by mechanical analyzes is the fatigue load. Two variants of the poloidal field coils are being investigated. The magnet and conductor design studies are accompanied by the experimental tests on both LTS and HTS prototype samples, covering a broad range of DC and AC tests. Testing of quench behavior of the 15 kA HTS cables, with size and layout relevant for the fusion magnets and cooled by forced flow helium, is in preparation.</p
Impact of the Mitochondrial Genetic Background in Complex III Deficiency
BACKGROUND: In recent years clinical evidence has emphasized the importance of the mtDNA genetic background that hosts a primary pathogenic mutation in the clinical expression of mitochondrial disorders, but little experimental confirmation has been provided. We have analyzed the pathogenic role of a novel homoplasmic mutation (m.15533 A>G) in the cytochrome b (MT-CYB) gene in a patient presenting with lactic acidosis, seizures, mild mental delay, and behaviour abnormalities. METHODOLOGY: Spectrophotometric analyses of the respiratory chain enzyme activities were performed in different tissues, the whole muscle mitochondrial DNA of the patient was sequenced, and the novel mutation was confirmed by PCR-RFLP. Transmitochondrial cybrids were constructed to confirm the pathogenicity of the mutation, and assembly/stability studies were carried out in fibroblasts and cybrids by means of mitochondrial translation inhibition in combination with blue native gel electrophoresis. PRINCIPAL FINDINGS: Biochemical analyses revealed a decrease in respiratory chain complex III activity in patient's skeletal muscle, and a combined enzyme defect of complexes III and IV in fibroblasts. Mutant transmitochondrial cybrids restored normal enzyme activities and steady-state protein levels, the mutation was mildly conserved along evolution, and the proband's mother and maternal aunt, both clinically unaffected, also harboured the homoplasmic mutation. These data suggested a nuclear genetic origin of the disease. However, by forcing the de novo functioning of the OXPHOS system, a severe delay in the biogenesis of the respiratory chain complexes was observed in the mutants, which demonstrated a direct functional effect of the mitochondrial genetic background. CONCLUSIONS: Our results point to possible pitfalls in the detection of pathogenic mitochondrial mutations, and highlight the role of the genetic mtDNA background in the development of mitochondrial disorders
Expansion of Signal Transduction Pathways in Fungi by Extensive Genome Duplication
International audienceno abstrac
Family physician and endocrinologist coordination as the basis for diabetes care in clinical practice
<p>Abstract</p> <p>Background</p> <p>To estimate the proportion of diabetic patients (DPts) with peripheral vascular disease treated at a primary health care site after an endocrinologist-based intervention, who meet ATP III and Steno targets of metabolic control, as well as to compare the outcome with the results of the patients treated by endocrinologists.</p> <p>Methods</p> <p>A controlled, prospective over 30-months period study was conducted in area 7 of Madrid. One hundred twenty six eligible diabetic patients diagnosed as having peripheral vascular disease between January 2003 and June 2004 were included in the study. After a treatment period of three months by the Diabetes team at St Carlos Hospital, 63 patients were randomly assigned to continue their follow up by diabetes team (Group A) and other 63 to be treated by the family physicians (FP) at primary care level with continuous diabetes team coordination (Group B). 57 DPts from Group A and 59 from Group B, completed the 30 months follow-up period. At baseline both groups were similar in age, weight, time from diagnosis and metabolic control. The main outcomes of this study were the proportion of patients meeting ATP III and Steno goals for HbA1c (%), Cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, blood pressure, albumine-to-creatinine excretion ratio (ACR), body mass index (BMI), waist circumference (WC), anti-aggregation treatment and smoking status.</p> <p>Results</p> <p>At the end of the follow up, no differences were found between the groups. More than 37% of diabetic patients assigned to be treated by FP achieved a HbA1c < 6.5%, more than 50% a ACR < 30 mg/g, and more than 80% reached low risk values for cholesterol, LDL cholesterol, triglycerides, diastolic blood pressure and were anti-aggregated, and 12% remained smokers. In contrast, less than 45% achieved a systolic blood pressure < 130 mm Hg, less than 12% had a BMI < 25 Kg.m-2 (versus 23% in group A; p < 0.05) and 49%/30% (men/women) had a waist circumference of low risk.</p> <p>Conclusion</p> <p>Improvements in metabolic control among diabetic patients with peripheral vascular disease treated at a primary health care setting is possible, reaching similar results to the patients treated at a specialized level. Despite such an improvement, body weight control remains more than poor in both levels, mainly at primary care level. General practitioner and endocrinologist coordination care may be important to enhance diabetes management in primary care settings.</p> <p>Trial registration</p> <p>Clinical Trial number ISRCTN75037597</p
Identification of novel risk loci, causal insights, and heritable risk for Parkinson's disease: a meta-analysis of genome-wide association studies
Background Genome-wide association studies (GWAS) in Parkinson's disease have increased the scope of biological knowledge about the disease over the past decade. We aimed to use the largest aggregate of GWAS data to identify novel risk loci and gain further insight into the causes of Parkinson's disease. Methods We did a meta-analysis of 17 datasets from Parkinson's disease GWAS available from European ancestry samples to nominate novel loci for disease risk. These datasets incorporated all available data. We then used these data to estimate heritable risk and develop predictive models of this heritability. We also used large gene expression and methylation resources to examine possible functional consequences as well as tissue, cell type, and biological pathway enrichments for the identified risk factors. Additionally, we examined shared genetic risk between Parkinson's disease and other phenotypes of interest via genetic correlations followed by Mendelian randomisation. Findings Between Oct 1, 2017, and Aug 9, 2018, we analysed 7·8 million single nucleotide polymorphisms in 37 688 cases, 18 618 UK Biobank proxy-cases (ie, individuals who do not have Parkinson's disease but have a first degree relative that does), and 1·4 million controls. We identified 90 independent genome-wide significant risk signals across 78 genomic regions, including 38 novel independent risk signals in 37 loci. These 90 variants explained 16–36% of the heritable risk of Parkinson's disease depending on prevalence. Integrating methylation and expression data within a Mendelian randomisation framework identified putatively associated genes at 70 risk signals underlying GWAS loci for follow-up functional studies. Tissue-specific expression enrichment analyses suggested Parkinson's disease loci were heavily brain-enriched, with specific neuronal cell types being implicated from single cell data. We found significant genetic correlations with brain volumes (false discovery rate-adjusted p=0·0035 for intracranial volume, p=0·024 for putamen volume), smoking status (p=0·024), and educational attainment (p=0·038). Mendelian randomisation between cognitive performance and Parkinson's disease risk showed a robust association (p=8·00 × 10−7). Interpretation These data provide the most comprehensive survey of genetic risk within Parkinson's disease to date, to the best of our knowledge, by revealing many additional Parkinson's disease risk loci, providing a biological context for these risk factors, and showing that a considerable genetic component of this disease remains unidentified. These associations derived from European ancestry datasets will need to be followed-up with more diverse data. Funding The National Institute on Aging at the National Institutes of Health (USA), The Michael J Fox Foundation, and The Parkinson's Foundation (see appendix for full list of funding sources)
- …