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1.
Microb Ecol ; 86(4): 2574-2582, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37415044

RESUMO

Ecological communities are structured by a range of processes that operate over a range of spatial scales. While our understanding of such biodiversity patterns in macro-communities is well studied, our understanding at the microbial level is still lacking. Bacteria can be free living or associated with host eukaryotes, forming part of a wider "microbiome," which is fundamental for host performance and health. For habitat forming foundation-species, host-bacteria relationships likely play disproportionate roles in mediating processes for the wider ecosystem. Here, we describe host-bacteria communities across multiple spatial scales (i.e., from 10s of m to 100s of km) in the understudied kelp, Eisenia cokeri, in Peru. We found that E. cokeri supports a distinct bacterial community compared to the surrounding seawater, but the structure of these communities varied markedly at the regional (~480 km), site (1-10 km), and individual (10s of m) scale. The marked regional-scale differences we observed may be driven by a range of processes, including temperature, upwelling intensity, or regional connectivity patterns. However, despite this variability, we observed consistency in the form of a persistent core community at the genus level. Here, the genera Arenicella, Blastopirellula, Granulosicoccus, and Litorimonas were found in >80% of samples and comprised ~53% of total sample abundance. These genera have been documented within bacterial communities associated with kelps and other seaweed species from around the world and may be important for host function and wider ecosystem health in general.


Assuntos
Kelp , Microbiota , Kelp/microbiologia , Ecossistema , Peru , Bactérias/genética , Biodiversidade
2.
Chron Respir Dis ; 18: 14799731211002240, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33729021

RESUMO

Knowledge on the sequelae of Coronavirus Disease 2019 (COVID-19) remains limited due to the relatively recent onset of this pathology. However, the literature on other types of coronavirus infections prior to COVID-19 reports that patients may experience persistent symptoms after discharge. To determine the prevalence of respiratory symptoms in survivors of hospital admission after COVID-19 infection. A living systematic review of five databases was performed in order to identify studies which reported the persistence of respiratory symptoms in COVID-19 patients after discharge. Two independent researchers reviewed and analysed the available literature, and then extracted and assessed the quality of those articles. Of the 1,154 reports returned by the initial search nine articles were found, in which 1,816 patients were included in the data synthesis. In the pooled analysis, we found a prevalence of 0.52 (CI 0.38-0.66, p < 0.01, I2 = 97%), 0.37 (CI 0.28-0.48, p < 0.01, I2 = 93%), 0.16 (CI 0.10-0.23, p < 0.01, I2 = 90%) and 0.14 (CI 0.06-0.24, p < 0.01, I2 = 96%) for fatigue, dyspnoea, chest pain, and cough, respectively. Fatigue, dyspnoea, chest pain, and cough were the most prevalent respiratory symptoms found in 52%, 37%, 16% and 14% of patients between 3 weeks and 3 months, after discharge in survivors of hospital admission by COVID-19, respectively.


Assuntos
COVID-19/complicações , COVID-19/fisiopatologia , Dor no Peito/epidemiologia , Tosse/epidemiologia , Dispneia/epidemiologia , Fadiga/epidemiologia , COVID-19/epidemiologia , Dor no Peito/fisiopatologia , Tosse/fisiopatologia , Dispneia/fisiopatologia , Fadiga/fisiopatologia , Humanos , Prevalência , SARS-CoV-2 , Sobreviventes , Síndrome de COVID-19 Pós-Aguda
3.
Rev Med Chil ; 145(12): 1588-1596, 2017 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-29652956

RESUMO

The prevalence and mortality of chronic obstructive pulmonary disease (COPD) is increasing in Chile, constituting a public health problem. Pulmonary and systemic consequences of COPD affect physical activity, as the disease progresses. There are multiple means for physical activity assessment, from low cost and easily applicable questionnaires to sophisticated laboratory tests. Physical inactivity is a modifiable risk factor for morbidity and mortality in patients with COPD. Physical activity interventions not only contribute to decrease the likelihood of mortality, but also protect from comorbidities, especially cardiovascular ones. It also plays a major role avoiding functional limitations of these subjects. Dyspnea and fatigue render exercise as an unpleasant activity for most patients with COPD. If psychological alterations such as anxiety and depression are summed, these patients drift towards an inactive lifestyle. This article analyzes several tools available to assess physical activity is patients with COPD, useful in clinical practice.


Assuntos
Teste de Esforço/métodos , Exercício Físico/psicologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Inquéritos e Questionários , Atividades Cotidianas , Teste de Esforço/instrumentação , Tolerância ao Exercício/fisiologia , Humanos , Monitorização Fisiológica/métodos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Reprodutibilidade dos Testes , Fatores de Tempo
4.
J Peripher Nerv Syst ; 21(4): 339-344, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27477441

RESUMO

The Guillain-Barré syndrome (GBS) incidence rate (IR) varies between 0.16 and 3.00 cases per 100,000 inhabitants. Little data exist on the epidemiology of GBS in Latin American countries. Our objective was to describe GBS epidemiology based on a national database in a Latin American country and to contribute to the global map of GBS epidemiology. This was a retrospective study that included all reported GBS cases in Chile between 2001 and 2012. Gender, age, seasonal occurrence, and geographical distribution were analyzed. A total of 4,158 GBS cases were identified from 19,513,655 registries. The mean age was 37 ± 24 years, and 59% of patients were male (male to female ratio of 1.5 : 1). Gender IR was 2.53/100,000 for males and 1.68/100,000 for females. The overall standardized IR was 2.1/100,000, although this varied between 1.61/100,000 (2001) and 2.35/100,000 (2010). The seasonal distribution was as follows: autumn 22%; winter 25%; spring 27%; and summer 26%. The geographical IR were as follows: far North 1.49/100,000; North 1.94/100,000; Central 1.97/100,000; South 3.18/100,000; and far South 2.78/100,000. The reported IR of GBS in Chile was similar to other studies based on national databases. In Chile, IR was greater in men and in the south.


Assuntos
Síndrome de Guillain-Barré/epidemiologia , Adulto , Distribuição por Idade , Fatores Etários , Chile/epidemiologia , Planejamento em Saúde Comunitária , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Distribuição por Sexo , Adulto Jovem
7.
Front Med (Lausanne) ; 10: 1284689, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38089877

RESUMO

Introduction: Obesity is a chronic medical condition that affects, among others, the cardiovascular and respiratory systems. Interventions for its treatment focus on sustained weight reduction and general health improvement, leaving respiratory management aside. Our objective was to determine the effects of inspiratory muscle training (IMT) in patients with obesity. Methods: A systematic review was performed in Embase, Cochrane Library (CENTRAL), CINAHL, Web of Science, and PubMed/MEDLINE on June 26, 2023. Randomized clinical trials (RCTs), and quasi-randomized clinical trials investigating the effects of IMT in people with obesity were included. Selected studies were screened by two independent reviewers who extracted data and assessed the quality of the evidence. Results: The initial search returned 705 potential studies were included. Ultimately, eight studies met the criteria for eligibility and were included in the review. IMT improves physical capacity [6-minute walk test (6MWT): 44.5 m, 95% CI: 30.5 to 58.5; p < 0.0001] and the strength of the inspiratory muscles [maximal inspiratory pressure (MIP): -28.4 cm H2O, 95% CI: -41.9 to -14.8; p < 0.0001] compared to the controls, without differences in the pulmonary function, body mass index (BMI) and metabolic parameters. Conclusion: Inspiratory muscle training improves physical capacity and inspiratory muscle strength without significant changes in lung function, BMI, and metabolic parameters.Systematic review registration: PROSPERO, identifier CRD42023439625, https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023439625.

8.
BMJ Open ; 12(5): e061624, 2022 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-35636801

RESUMO

INTRODUCTION: Respiratory muscle weakness and ventilatory failure are common complications in patients with amyotrophic lateral sclerosis (ALS) and may lead to death. Respiratory physiotherapy may improve lung function in this population. This study aims to investigate the effects of respiratory physiotherapy on lung function, cough efficacy and functional status of patients with ALS. METHODS AND ANALYSIS: A protocol was published on the International prospective register of systematic reviews (PROSPERO). The research will cover randomised controlled trials, with no language or publication date restriction, available in the following databases: MEDLINE/PubMed, EMBASE, Cochrane Library, Web of Science and Physiotherapy Evidence Database. The research question will be answered using a search strategy adapted for each database. Searches in databases will be conducted from January 2021 to December 2022. Two authors using the Cochrane risk of bias tool for randomised trials V.2 and Grading of Recommendations, Assessment, Development and Evaluations, respectively, will assess risk of bias and quality of evidence independently. According to the results obtained, data will be reported as a meta-analysis or a narrative report. ETHICS AND DISSEMINATION: No previous ethical approval is required for this publication since data used are already published. Results of this review will be disclosed via peer-reviewed publications and conference presentations. PROSPERO REGISTRATION NUMBER: CRD42021251842.


Assuntos
Esclerose Lateral Amiotrófica , Insuficiência Respiratória , Esclerose Lateral Amiotrófica/complicações , Esclerose Lateral Amiotrófica/terapia , Humanos , Metanálise como Assunto , Modalidades de Fisioterapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapia , Literatura de Revisão como Assunto , Revisões Sistemáticas como Assunto
9.
Clocks Sleep ; 4(2): 219-229, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35466271

RESUMO

Background: Effective treatments for obstructive sleep apnoea (OSA) include positive pressure, weight loss, oral appliances, surgery, and exercise. Although the involvement of the respiratory muscles in OSA is evident, the effect of training them to improve clinical outcomes is not clear. We aimed to determine the effects of respiratory muscle training in patients with OSA. Methods: A systematic review was conducted in seven databases. Studies that applied respiratory muscle training in OSA patients were reviewed. Two independent reviewers analysed the studies, extracted the data and assessed the quality of evidence. Results: Of the 405 reports returned by the initial search, eight articles reporting on 210 patients were included in the data synthesis. Seven included inspiratory muscle training (IMT), and one included expiratory muscle training (EMT). Regarding IMT, we found significant improvement in Epworth sleepiness scale in −4.45 points (95%CI −7.64 to −1.27 points, p = 0.006), in Pittsburgh sleep quality index of −2.79 points (95%CI −4.19 to −1.39 points, p < 0.0001), and maximum inspiratory pressure of −29.56 cmH2O (95%CI −53.14 to −5.98 cmH2O, p = 0.01). However, the apnoea/hypopnea index and physical capacity did not show changes. We did not perform a meta-analysis of EMT due to insufficient studies. Conclusion: IMT improves sleepiness, sleep quality and inspiratory strength in patients with OSA.

10.
Front Med (Lausanne) ; 9: 934410, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36388881

RESUMO

Background: Quadriceps muscle training is a key part in the rehabilitation of chronic obstructive pulmonary disease (COPD) patients. However, exercise intensity prescription and progression with the typically used elastic bands is challenging. We aimed to evaluate neuromuscular, acute symptoms and cardiorespiratory responses (heart rate and dyspnea) during progressive elastic resistance exercise in patients with COPD. Methods: Fourteen patients diagnosed with moderate-very severe COPD performed knee extensions at different elastic resistance levels (i.e., colors). The neuromuscular activity was recorded using surface electromyography for the rectus femoris, vastus lateralis and vastus medialis, together with rate of perceived exertion, perceived quadriceps fatigue, dyspnea, oxygen saturation and heart rate. Results: For the vastus lateralis and rectus femoris, increase of muscle activity was evident from a two-level increment when using the red color. For the vastus medialis, there were no muscle activity progressions. Dyspnea, quadriceps fatigue and especially rate of perceived exertion increased in a dose-response fashion and were correlated with the resistance level and muscle activity at the three muscles. Conclusion: Heavy elastic resistance exercise is feasible in COPD patients without excessive dyspnea and a stable cardiorespiratory response. In general, at least two elastic resistance increments are needed to enhance muscle activity for the vastus lateralis and rectus femoris, while there is no increase for the vastus medialis. These results may help to individualize exercise dosing during elastic resistance training in patients with COPD.

11.
J Phys Act Health ; 18(2): 219-229, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33440346

RESUMO

BACKGROUND: The literature is unclear as to whether children and adolescents with chronic respiratory diseases (CRDs) differ from their healthy peers in physical activity (PA). OBJECTIVE: To determine the PA levels measured through accelerometers in children and adolescents with CRDs. METHODS: The authors conducted a systematic review using five databases. The authors included studies that assessed the PA measured by accelerometers in children and adolescents with CRDs. Two independent reviewers analyzed the studies, extracted the data, and assessed the quality of evidence. RESULTS: From 11,497 reports returned by the initial search, 29 articles reporting on 4381 patients were included. In the sensitivity analysis, the authors found that children and adolescents with CRDs had a moderate-to-vigorous PA (MVPA) of -0.08 hours per day (95% confidence interval [CI], -0.12 to -0.03 h/d; P = .001), which was lower than the healthy controls; the values for sedentary time (mean difference -0.47 h/d; 95% CI, -1.29 to 0.36 h/d; P = .27) and steps/d (mean difference 361 steps/d; 95% CI -385 to 1707 steps/d; P = .45) were similar for both. CONCLUSION: Children and adolescents with CRDs have a slight reduction in MVPA in comparison with healthy controls, but sedentary time and steps/d were similar for both.


Assuntos
Exercício Físico , Comportamento Sedentário , Adolescente , Criança , Humanos
12.
PeerJ ; 9: e11026, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33868804

RESUMO

BACKGROUND: Coronavirus disease has provoked much discussion since its first appearance. Despite it being widely studied all over the world, little is known about the impact of the disease on functional ability related to performing activities of daily living (ADL) in patients post COVID-19 infection. OBJECTIVES: To understand the impact of COVID-19 on ADL performance of adult patients and to describe the common scales used to assess performance of ADL on patients post-COVID-19. METHODS: A systematic review was conducted. We included studies that applied a physical capacity test in COVID-19 patients, post-infection. Two independent reviewers analyzed the studies, extracted the data, and assessed the quality of the evidence. RESULTS: A total of 1,228 studies were included, after removing duplicates, 1,005 abstracts were screened and of those 983 were excluded. A final number of nine studies which met the eligibility criteria were included. The findings revealed worsening of physical function and ADL performance in all patients post COVID-19 infection. CONCLUSION: All included studies found a reduction of ADL beyond the test or scale used, revealing a vital worsening of functional ability in ADL performance and consequently loss of independence in COVID-19 patients after the acute phase of infection. Functional ability status previous to COVID-19 is crucial for predicting the severity of the disease and mortality. Barthel Index and ADL score were the most used assessment tools across subjects with different intrinsic capacity and context levels.

13.
J Clin Neurosci ; 80: 292-297, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32674942

RESUMO

BACKGROUND: The clinical characteristics of electrophysiological subtypes and prognostic factors of Mexican adults diagnosed with Guillain-Barré Syndrome (GBS) have not been described. MATERIALS AND METHODS: A single center, ambispective, cohort study was performed (2015-2019). GBS was defined following the Asbury and Cornblath criteria. Electrodiagnosis was made according to Hadden criteria. Clinical, biochemical and electrodiagnostic parameters were described, compared and analyzed using a multivariate model. Only patients who completed a 3-month follow-up were included. RESULTS: 137 GBS patients (92 males; mean age 46.6 ± 16.6).132 (96.3%) underwent an electrodiagnostic assessment.68 (51.5%) were classified as axonal GBS, with further classified into two groups: acute motor axonal neuropathy (AMAN) 45.4%, and acute motor and sensory axonal neuropathy (AMSAN) 8,6%. The following characteristics were lower in the AMAN group: Medical Research Counsel sumscore (MRC) 30.1 ± 16.3 vs 36.4 ± 14.4, unilateral facial palsy 10% vs 25.9% and albuminocytologic dissociation 41.3% vs. 71.7%.Multivariate analysis found AMAN as an independent predictor of an unfavorable outcome OR: 3.34 (p = 0.03) CONCLUSIONS: AMAN subtype is the most frequent presentation of GBS in Mexican adult patients and an independent predictor of inability to walk independently at 3 months after discharge.


Assuntos
Eletrodiagnóstico/métodos , Fenômenos Eletrofisiológicos/fisiologia , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/fisiopatologia , Condução Nervosa/fisiologia , Caminhada/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Seguimentos , Síndrome de Guillain-Barré/epidemiologia , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
14.
J Neurol ; 267(3): 674-678, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31720821

RESUMO

INTRODUCTION: Refractory myasthenia gravis (MG) is defined as a failure to respond adequately to conventional therapies, the inability to reduce immunosuppressive therapy without clinical relapse or the need for ongoing rescue therapy, severe adverse effects from immunosuppressive therapy (treatment intolerant) or frequent myasthenic crisis even on therapy. Cyclophosphamide (CYC) is a DNA alkylating agent that causes important interference in transcription processes and DNA replication, it has been used in refractory MG with controversial results. We aim to determine the efficacy of CYC in refractory MG in the Mexican population. METHODS: In an observational, longitudinal retrospective study, we identified eight refractory MG patients treated with 30-50 mg/kg monthly CYC for at least 6 months. The efficacy was assessed by Osserman scale considering significant improvement a ≥ 1 point reduction and Myasthenia Gravis Composite Scale. The relapse-free and remission-free period were also calculated using the Kaplan-Meier statistic. RESULTS: Clinical improvement was achieved in 75% of the patients. According to the Kaplan-Meier analysis, the median progression-free survival (PFS) was 9 (6.2-11.5) months and the median time to progression (TTP) was 4 (1-8) months. Response was independent of patient's characteristics, except for the MG age of onset (p = 0.0025). CONCLUSIONS: CYC was effective in all patients with refractory MG for a mean of 9 months, with worsening thereafter, which could be associated with low cumulative dose. The symptomatic improvement with CYC was noted within the 1st month. We conclude that CYC is effective as an induction to remission therapy, although our data suggest it is not effective as a long-term therapy.


Assuntos
Ciclofosfamida/administração & dosagem , Imunossupressores/administração & dosagem , Miastenia Gravis/tratamento farmacológico , Administração Intravenosa , Adulto , Idoso , Resistência a Medicamentos/efeitos dos fármacos , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
15.
Int J Oral Maxillofac Implants ; 24(5): 936-42, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19865635

RESUMO

PURPOSE: The aim of this study was to present an alternative treatment concept for the rehabilitation of the atrophic maxilla that used the nasopalatine canal as an anatomic buttress for dental implant insertion and to assess patient satisfaction with this treatment. MATERIALS AND METHODS: The inclusion criterion for the study consisted of the presence of severe resorption of the edentulous maxilla (Class V according to the Cawood and Howell classification). In each patient, one implant was positioned in the nasopalatine canal. Additional implants were also placed in the remaining maxillary bone. The patients were followed for a minimum of 2 years after prosthesis connection. Satisfaction with the prosthesis was evaluated after 12 months using a visual analog scale. RESULTS: Seven patients with severely resorbed edentulous maxillae received a total of seven implants in the nasopalatine buttress and 29 implants posterior to this structure. One of the seven implants in the nasopalatine canal was lost during the osseointegration phase. All patients had stable prostheses at the end of the observation period. Patients were satisfied with comfort and stability, ability to speak, ease of cleaning, and esthetics and function of the prosthesis. Five patients experienced minor sensory alterations during the first weeks after surgery. At the final examination, which took place after a mean of 5 years (range, 3 to 7 years), all patients expressed the presence of normal sensation. CONCLUSIONS: It appears that implants in the nasopalatine canal may be a viable treatment approach for the rehabilitation of the severely atrophied maxilla. Patients were satisfied with a prosthesis supported by implants in the nasopalatine canal.


Assuntos
Implantes Dentários , Maxila/cirurgia , Cavidade Nasal/cirurgia , Palato Duro/cirurgia , Adulto , Idoso , Atrofia , Reabsorção Óssea/cirurgia , Implantação Dentária Endóssea , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Prótese Total Superior , Estética Dentária , Feminino , Seguimentos , Humanos , Arcada Edêntula/reabilitação , Arcada Edêntula/cirurgia , Masculino , Maxila/patologia , Pessoa de Meia-Idade , Higiene Bucal , Osseointegração/fisiologia , Osteotomia/métodos , Satisfação do Paciente , Projetos Piloto , Sensação/fisiologia , Fala/fisiologia
16.
PLoS One ; 14(10): e0224357, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31648267

RESUMO

Measurement of respiratory muscles strength such as maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) are used to detect, diagnose and treat respiratory weakness. However, devices used for these measurements are not widely available and are costly. Currently, the use of a digital manometer is recommended. In industry, several inexpensive devices are available, but these have not been validated for clinical use. Our objective was to determine the agreement between maximal respiratory pressures obtained with a clinical digital manometer and that with a non-clinical digital manometer in healthy volunteers. We assessed the height, weight, lung function, MIP, and MEP of healthy volunteers. To compare pressures obtained by each type of digital manometer, a parallel approach configuration was used. The agreement was measured with the Intraclass Coefficient Correlation (ICC) and the Bland-Altman plot. Twenty-seven participants (14 men) were recruited with a median age of 22 (range: 21-23) years. Each participant underwent three measurements to give a total of 81 measurements. The mean MIPs were 90.8 ± 26.4 (SEM 2.9) and 91.1 ± 26.4 (SEM 2.9) cmH2O for the clinical and non-clinical digital manometers, respectively. The mean MEPs were 113.8 ± 40.4 (SEM 4.5) and 114.5 ± 40.5 (SEM 4.5) cmH2O for the clinical and non-clinical digital manometers, respectively. We obtained an ICC of 0.998 (IC 0.997-0.999) for MIP and 0.999 (IC 0.998-0.999) for MEP. There is a high agreement in the values obtained for MIP and MEP between clinical and non-clinical digital manometers in healthy volunteers. Further validation at lower pressures and safety profiling among human subjects is needed.


Assuntos
Pressões Respiratórias Máximas/instrumentação , Estudos Transversais , Feminino , Voluntários Saudáveis , Humanos , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
17.
Beilstein J Nanotechnol ; 9: 545-554, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29527431

RESUMO

Carbon nanotube (CNT) yarns exhibit low tensile strength compared to conventional high-performance carbon fibers due to the facile sliding of CNTs past one another. Electron beam (e-beam) irradiation was employed for in a single-step surface modification of CNTs to improve the mechanical properties of this material. To this end, CNT yarns were simultaneously functionalized and crosslinked using acrylic acid (AA) and acrylonitrile (AN) in an e-beam irradiation process. The chemical modification of CNT yarns was confirmed by X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and scanning electron microscopy (SEM). The best improvement in mechanical properties was achieved on a sample treated with an aqueous solution of AA and subsequent irradiation. CNT yarn treatment with AA enhanced the strength (444.5 ± 68.4 MPa) by more than 75% and the modulus (21.5 ± 0.6 GPa) by more than 144% as compared to untreated CNT yarn (strength 251 ± 26.5 MPa and modulus 8.8 ± 1.2 GPa).

18.
Eur J Case Rep Intern Med ; 5(8): 000912, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30756060

RESUMO

BACKGROUND: Bilateral third cranial nerve palsy has only been reported in a handful of conditions including some with inflammatory, tumoural and vascular causes. An urgent imaging study is mandatory to rule out vascular aetiology, mainly aneurysmal subarachnoid haemorrhage (aSAH). CASE PRESENTATION: A 28-year-old Hispanic woman presented to the emergency department with a 21-day history of a sudden-onset and severe headache that on three occasions was accompanied by transient loss of awareness, the last episode occurring a week previously. The simple CT image showed minimal bleeding at the level of the perimesencephalic cisterns, with evidence of SAH. An angioCT revealed a 5×6 mm bilobed saccular aneurysm of the right posterior communicating artery and a 2×2 mm saccular aneurysm in the posterior left communicating artery. CONCLUSIONS: A mirror aneurysm is found in 2-25% of aSAH cases. To date there is no consensus about the optimal management of patients with these findings. LEARNING POINTS: The presence of third cranial nerve palsy should always raise the suspicion of an aneurysm.Subarachnoid haemorrhage is the most common cause of a thunderclap headache.Aneurysmal subarachnoid haemorrhage requires surgical management in all cases.

19.
Appl Radiat Isot ; 111: 26-30, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26901240

RESUMO

Calcium carbonate received gamma irradiation at different doses (0-309kGy) and temperature regimes (77-298K) to study the effects of irradiation temperature. The changes were followed by EPR spectroscopy. We observed the formation of a composite EPR spectrum, even at low radiation doses and temperature. There was a strong effect on the evaluation of the radicals formed as a function of irradiation temperature, probably due to the diffusion in the frozen powder and the recombination of some radicals at room temperature.

20.
Int J Food Microbiol ; 232: 43-51, 2016 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-27240219

RESUMO

Human norovirus (NoV) is a major cause of fresh produce-associated outbreaks and human NoV in irrigation water can potentially lead to viral internalization in fresh produce. Therefore, there is a need to develop novel intervention strategies to target internalized viral pathogens while maintaining fresh produce quality. In this study electron beam (E-beam) and gamma radiation were evaluated for efficacy against a human NoV GII.4 strain and Tulane virus (TV). Virus survival following ionizing radiation treatments was determined using direct quantitative reverse transcriptase PCR (RT-qPCR), the porcine gastric mucin magnetic bead (PGM-MB) binding assay followed by RT-qPCR, and plaque assay. In simple media, a high dose of E-beam treatment was required to completely abolish the receptor binding ability of human NoV (35.3kGy) and TV (19.5-24.1kGy), as assessed using the PGM-MB binding assay. Both human NoV and TV were more susceptible to gamma irradiation than E-beam, requiring 22.4kGy to achieve complete inactivation. In whole strawberries, no human NoV or TV RNA was detected following 28.7kGy of E-beam treatment using the PGM-MB binding assay. Overall, human NoV and TV are highly resistant to ionizing radiation and therefore the technology may not be suitable to eliminate viruses in fresh produce at the currently approved levels. In addition, the PGM-MB binding assay is an improved method to detect viral infectivity compared to direct RT-qPCR.


Assuntos
Infecções por Caliciviridae/prevenção & controle , Fragaria/virologia , Gastroenterite/prevenção & controle , Norovirus/efeitos da radiação , Ligação Viral/efeitos da radiação , Inativação de Vírus/efeitos da radiação , Animais , Infecções por Caliciviridae/virologia , Surtos de Doenças , Raios gama , Mucinas Gástricas/metabolismo , Gastroenterite/virologia , Humanos , Separação Imunomagnética , Norovirus/classificação , Norovirus/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Suínos/virologia , Internalização do Vírus/efeitos da radiação
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