307 research outputs found

    Electro-Magnetic Earthquake Bursts and Critical Rupture of Peroxy Bond Networks in Rocks

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    We propose a mechanism for the low frequency electromagnetic emissions and other electromagnetic phenomena which have been associated with earthquakes. The mechanism combines the critical earthquake concept and the concept of crust acting as a charging electric battery under increasing stress. The electric charges are released by activation of dormant charge carriers in the oxygen anion sublattice, called peroxy bonds or positive hole pairs (PHP), where a PHP represents an O3X/OO\YO3O_3X/^{OO}\backslash YO_3 with X,Y=Si4+,Al3+...X,Y = Si^{4+}, Al^{3+}..., i.e. an OO^- in a matrix of O2O^{2-} of silicates. We propose that PHP are activated by plastic deformations during the slow cooperative build-up of stress and the increasingly correlated damage culminating in a large ``critical'' earthquake. Recent laboratory experiments indeed show that stressed rocks form electric batteries which can release their charge when a conducting path closes the equivalent electric circuit. We conjecture that the intermittent and erratic occurrences of EM signals are a consequence of the progressive build-up of the battery charges in the Earth crust and their erratic release when crack networks are percolating throughout the stressed rock volumes, providing a conductive pathway for the battery currents to discharge. EM signals are thus expected close to the rupture, either slightly before or after, that is, when percolation is most favored.Comment: 17 pages with 3 figures, extended discussion with 1 added figure and 162 references. The new version provides both a synthesis of two theories and a review of the fiel

    Detection of Neutralizing Antibodies in COVID-19 Patients from Steve Biko Academic Hospital Complex: A Pilot Study

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    A correlation between neutralization activity after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination and protection against coronavirus disease 2019 (COVID-19) has been demonstrated by several studies. Here, we detect SARS-CoV-2 neutralizing antibody (NAB) production in COVID-19 patients from the Steve Biko Academic Hospital complex (SBAH), South Africa (SA). Samples from COVID-19 patients (mild to severe) were collected. SARS-CoV-2 rapid assays, genotyping (Delta and Omicron variants) and enzyme-linked immunosorbent assays (ELISA) were performed. IBM® Statistical Package for the Social Sciences (SPSS®) version 28 was used for inferential statistical analysis, and the data were presented using the Prism9 software (version 9.4.1). A total of 137 laboratory-confirmed COVID-19 patients, 12 vaccine recipients and 8 unvaccinated participants were evaluated. The production of SARS-CoV-2 NABs was observed in some of the COVID-19 cases, mainly in severe cases, although this should be noted with caution due to the small sample size of this pilot study. NABs were also observed in asymptomatic participants, with the most being found in recipients (n = 6) of the BNT162b2 (Pfizer-BioNTech) COVID-19 vaccine. We found a strong presence of NABs in COVID-19 patients, specifically in mild and severe cases. Severe infection was associated with higher NAB production (82%).P.M thanks H2020-WIDESPREAD-2018-951921-ImmunoHUB for the financial support

    CONHECIMENTOS DE UNIVERSITÁRIOS DA ÁREA DA SAÚDE SOBRE CONTRACEPÇÃO E PREVENÇÃO DE DOENÇAS SEXUALMENTE TRANSMISSÍVEIS

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    Human sexuality is an important component in the individual’s formation. Sexuality has experienced important changes during human history, such as people’s access to information. In this sense we want to investigate the university students’ knowledge in the area of health at the Federal del Ceará University, Colombia regarding behaviors about contraception and STD prevention, since these future professionals will be an important source of information for the population. Data was obtained between May and June 2005 using a questionnaire of 12 objective questions about sexual education, sexual life and knowledge about pregnancy and STD prevention. Regarding information about sex, family, friends and school were the main sources of information. When asked if HIV could be transmitted through oral sex, 87.5% answered correctly, by responding that yes. There is certain knowledge about sexuality among the students. Nevertheless, there is still a lack of preventive knowledge regarding sexual health.La sexualidad humana es un componente importante en la formación del individuo. Sufrió importantes modificaciones a lo largo de la existencia de la vida humana, como la mayor divulgación de informaciones. Buscamos investigar el conocimiento de los universitarios del área de salud de la Universidad Federal del Ceará referente a las conductas de contracepción y prevención de DST, puesto que estas son una importante fuente de información para la población. La colecta de datos tuvo lugar entre mayo y junio de 2005 por medio de un cuestionario objetivo compuesto de 12 preguntas, acerca de la educación sexual, sexualidad y conocimiento en la prevención del embarazo no deseado y de DST. En cuanto a la orientación sexual, la familia, los amigos y la escuela fueron las principales fuentes de información. Preguntados si la transmisión del VIH se produce a través de sexo oral, 87,5% respondió correctamente al afirmar la cuestión como verdadera. Percibimos cierto conocimiento sobre la sexualidad entre los estudiantes, no obstante todavía hay carencias sobre algunos aspectos preventivos de salud sexual.A sexualidade humana é um importante componente na formação do indivíduo. Esta sofreu importantes modificações ao longo da existência da vida humana, como uma maior divulgação de informações. Assim, buscamos investigar o conhecimento de universitários da área da saúde acerca das condutas de contracepção e prevenção de DST, já que estes são importante fonte de informação para a população. A coleta de dados ocorreu entre maio e junho de 2005 por meio de questionário objetivo com 12 questões, abordando dados relacionados à orientação sexual, sexualidade e conhecimento sobre prevenção de DST e gravidez indesejada. Quanto à orientação sexual a família, amigos e a escola foram as principais fontes de informação. Questionados se a transmissão do HIV ocorre através de sexo oral, 87,5% responderam corretamente ao afirmar a questão como verdadeira. Percebemos certo conhecimento sobre a sexualidade entre os universitários, porém ainda há carências sobre alguns aspectos preventivos da saúde sexua

    Reduced transcription of TCOF1 in adult cells of Treacher Collins syndrome patients

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    <p>Abstract</p> <p>Background</p> <p>Treacher Collins syndrome (TCS) is an autosomal dominant craniofacial disorder caused by frameshift deletions or duplications in the <it>TCOF1 </it>gene. These mutations cause premature termination codons, which are predicted to lead to mRNA degradation by nonsense mediated mRNA decay (NMD). Haploinsufficiency of the gene product (treacle) during embryonic development is the proposed molecular mechanism underlying TCS. However, it is still unknown if <it>TCOF1 </it>expression levels are decreased in post-embryonic human cells.</p> <p>Methods</p> <p>We have estimated <it>TCOF1 </it>transcript levels through real time PCR in mRNA obtained from leucocytes and mesenchymal cells of TCS patients (n = 23) and controls (n = 18). Mutational screening and analysis of NMD were performed by direct sequencing of gDNA and cDNA, respectively.</p> <p>Results</p> <p>All the 23 patients had typical clinical features of the syndrome and pathogenic mutations were detected in 19 of them. We demonstrated that the expression level of <it>TCOF1 </it>is 18-31% lower in patients than in controls (<it>p < 0.05</it>), even if we exclude the patients in whom we did not detect the pathogenic mutation. We also observed that the mutant allele is usually less abundant than the wild type one in mesenchymal cells.</p> <p>Conclusions</p> <p>This is the first study to report decreased expression levels of <it>TCOF1 </it>in TCS adult human cells, but it is still unknown if this finding is associated to any phenotype in adulthood. In addition, as we demonstrated that alleles harboring the pathogenic mutations have lower expression, we herein corroborate the current hypothesis of NMD of the mutant transcript as the explanation for diminished levels of <it>TCOF1 </it>expression. Further, considering that <it>TCOF1 </it>deficiency in adult cells could be associated to pathologic clinical findings, it will be important to verify if TCS patients have an impairment in adult stem cell properties, as this can reduce the efficiency of plastic surgery results during rehabilitation of these patients.</p

    Evidence for Cognitive Impairment in Mastocytosis: Prevalence, Features and Correlations to Depression

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    Mastocytosis is a heterogeneous disease characterized by mast cells accumulation in one or more organs. We have reported that depression is frequent in mastocytosis, but although it was already described, little is known about the prevalence and features of cognitive impairment. Our objective was to describe the prevalence and features of cognitive impairment in a large cohort of patients with this rare disease (n = 57; mean age = 45) and to explore the relations between memory impairment and depression. Objective memory impairment was evaluated using the 3rd edition of the Clinical Memory scale of Wechsler. Depression symptoms were evaluated using the Hamilton Depression Rating Scale. Age and education levels were controlled for all patients. Patients with mastocytosis presented high levels of cognitive impairment (memory and/or attention) (n = 22; 38.6%). Cognitive impairment was moderate in 59% of the cases, concerned immediate auditory (41%) and working memory (73%) and was not associated to depression (p≥0.717). In conclusion, immediate auditory memory and attention impairment in mastocytosis are frequent, even in young individuals, and are not consecutive to depression. In mastocytosis, cognitive complaints call for complex neuropsychological assessment. Mild-moderate cognitive impairment and depression constitute two specific but somewhat independent syndromes in mastocytosis. These results suggest differential effects of mast-cell activity in the brain, on systems involved in emotionality and in cognition

    Production and characterization of a recombinant single-chain antibody against Hantaan virus envelop glycoprotein

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    Hantaan virus (HTNV) is the type of Hantavirus causing hemorrhagic fever with renal syndrome, for which no specific therapeutics are available so far. Cell type-specific internalizing antibodies can be used to deliver therapeutics intracellularly to target cell and thus, have potential application in anti-HTNV infection. To achieve intracellular delivery of therapeutics, it is necessary to obtain antibodies that demonstrate sufficient cell type-specific binding, internalizing, and desired cellular trafficking. Here, we describe the prokaryotic expression, affinity purification, and functional testing of a single-chain Fv antibody fragment (scFv) against HTNV envelop glycoprotein (GP), an HTNV-specific antigen normally located on the membranes of HTNV-infected cells. This HTNV GP-targeting antibody, scFv3G1, was produced in the cytoplasm of Escherichia coli cells as a soluble protein and was purified by immobilized metal affinity chromatography. The purified scFv possessed a high specific antigen-binding activity to HTNV GP and HTNV-infected Vero E6 cells and could be internalized into HTNV-infected cells probably through the clathrin-dependent endocytosis pathways similar to that observed with transferrin. Our results showed that the E. coli-produced scFv had potential applications in targeted and intracellular delivery of therapeutics against HTNV infections

    A generic emergency protocol for patients with inborn errors of metabolism causing fasting intolerance: A retrospective, single-center study and the generation of www.emergencyprotocol.net

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    Patients with inborn errors of metabolism causing fasting intolerance can experience acute metabolic decompensations. Long-term data on outcomes using emergency letters are lacking. This is a retrospective, observational, single-center study of the use of emergency letters based on a generic emergency protocol in patients with hepatic glycogen storage diseases (GSD) or fatty acid oxidation disorders (FAOD). Data on hospital admissions, initial laboratory results, and serious adverse events were collected. Subsequently, the website www.emergencyprotocol.net was generated in the context of the CONNECT MetabERN eHealth project following multiple meetings, protocol revisions, and translations. Representing 470 emergency protocol years, 127 hospital admissions were documented in 54/128 (42%) patients who made use of emergency letters generated based on the generic emergency protocol. Hypoglycemia (here defined as glucose concentration 5 years. Convulsions, coma, or death was not documented. By providing basic information, emergency letters for individual patients with hepatic GSD or the main FAOD can be generated at www.emergencyprotocol.net, in nine different languages. Generic emergency protocols are safe and easy for home management by the caregivers and the first hour in-hospital management to prevent metabolic emergencies in patients with hepatic GSD and medium-chain Acyl CoA dehydrogenase deficiency. The website www.emergencyprotocol.net is designed to support families and healthcare providers to generate personalized emergency letters for patients with hepatic GSD and the main FAOD
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