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1.
N Engl J Med ; 388(5): 427-438, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36724329

RESUMO

BACKGROUND: In September 2015, the four-component, protein-based meningococcal serogroup B vaccine (4CMenB; Bexsero) became available for private purchase in Spain. METHODS: We conducted a nationwide matched case-control study to assess the effectiveness of 4CMenB in preventing invasive meningococcal disease in children. The study included all laboratory-confirmed cases of invasive meningococcal disease in children younger than 60 months of age between October 5, 2015, and October 6, 2019, in Spain. Each case patient was matched with four controls according to date of birth and province. 4CMenB vaccination status of the case patients and controls was compared with the use of multivariate conditional logistic regression. RESULTS: We compared 306 case patients (243 [79.4%] with serogroup B disease) with 1224 controls. A total of 35 case patients (11.4%) and 298 controls (24.3%) had received at least one dose of 4CMenB. The effectiveness of complete vaccination with 4CMenB (defined as receipt of at least 2 doses, administered in accordance with the manufacturer's recommendations) was 76% (95% confidence interval [CI], 57 to 87) against invasive meningococcal disease caused by any serogroup, and partial vaccination was 54% (95% CI, 18 to 74) effective. Complete vaccination resulted in an effectiveness of 71% (95% CI, 45 to 85) against meningococcal serogroup B disease. Vaccine effectiveness with at least one dose of 4CMenB was 64% (95% CI, 41 to 78) against serogroup B disease and 82% (95% CI, 21 to 96) against non-serogroup B disease. With the use of the genetic Meningococcal Antigen Typing System, serogroup B strains that were expected to be covered by 4CMenB were detected in 44 case patients, none of whom had been vaccinated. CONCLUSIONS: Complete vaccination with 4CMenB was found to be effective in preventing invasive disease by serogroup B and non-serogroup B meningococci in children younger than 5 years of age.


Assuntos
Infecções Meningocócicas , Vacinas Meningocócicas , Neisseria meningitidis Sorogrupo B , Criança , Humanos , Lactente , Estudos de Casos e Controles , Infecções Meningocócicas/microbiologia , Infecções Meningocócicas/prevenção & controle , Vacinas Meningocócicas/uso terapêutico , Neisseria meningitidis , Espanha
2.
Rev Med Chil ; 150(2): 183-189, 2022 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-36156644

RESUMO

COVID-19 pandemic generated multiple challenges for the health system. Cardiovascular disease is associated with a worse prognosis of infections. Moreover, most hospital resources and operative rooms were destined to patients with COVID-19 infection, deferring the treatment of most valvular patients requiring surgery. We report seven patients with symptomatic severe aortic stenosis who underwent transcatheter aortic valve implantation (TAVI) with conscious sedation and early discharge. No patient required intensive care unit admission or mechanical ventilation. After a 90-day follow-up, there were no complications or unplanned readmissions.


Assuntos
Estenose da Valva Aórtica , COVID-19 , Substituição da Valva Aórtica Transcateter , Estenose da Valva Aórtica/etiologia , Estenose da Valva Aórtica/cirurgia , Sedação Consciente/efeitos adversos , Humanos , Pandemias , Alta do Paciente , Fatores de Risco , Substituição da Valva Aórtica Transcateter/efeitos adversos , Resultado do Tratamento
3.
Ann Hematol ; 100(2): 353-364, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33159567

RESUMO

Congenital dyserythropoietic anemias (CDA) are disorders characterized by ineffective erythropoiesis and morphological anomalies in erythrocytes and erythroblasts. The purpose of this study is to identify the gene variants in patients diagnosed with CDA. We analyzed five unrelated patients and two siblings with a targeted panel of genes to CDA: CDAN1, CDIN1, SEC23B, KIF23, KLF1, and GATA1 genes. We found three novel variants in the CDIN1 gene (p.Leu136Val, p.Tyr247Cys, and p.Ile273Thr), four known variants in the SEC23B gene (p.Arg14Trp, p.Arg554Ter, p.Asp239Gly, and p.Ser436Leu), and one novel variant in the KIF23 gene (p.Leu945Trpfs*31). The in silico analysis of novel variants predict that they are pathogenic and, the in vitro study confirms the functional impact of the KIF23 variant on the protein location.


Assuntos
Anemia Diseritropoética Congênita/classificação , Anemia Diseritropoética Congênita/genética , Proteínas Associadas aos Microtúbulos/genética , Mutação de Sentido Incorreto , Adolescente , Adulto , Substituição de Aminoácidos , Criança , Feminino , Humanos , Masculino
4.
ScientificWorldJournal ; 2021: 6664636, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34421400

RESUMO

Recently, the interest in donkey milk has increased considerably because it proved high nutritive and functional values of their ingredients. Its chemical composition is widely studied, but its microbiota, especially lactic acid bacteria, remains less studied. This study focuses on analyzing, isolating, and identifying lactic acid bacteria and evaluating their capacity to produce biomolecules with antibacterial activity. Among 44 strains identified, 43 are Gram-positive, and most are catalase-negative and cocci-shaped. Five strains were selected to evaluate their antibacterial activity against Listeria monocytogenes, Staphylococcus aureus, and Escherichia coli. Different induction methods allowed to amplify the antibacterial effects against these pathogenic strains.


Assuntos
Aerococcus/isolamento & purificação , Antibacterianos/farmacologia , Meios de Cultivo Condicionados/farmacologia , Enterococcus faecalis/isolamento & purificação , Enterococcus/isolamento & purificação , Leuconostoc mesenteroides/isolamento & purificação , Aerococcus/química , Aerococcus/metabolismo , Animais , Indústria de Laticínios/métodos , Enterococcus/química , Enterococcus/metabolismo , Enterococcus faecalis/química , Enterococcus faecalis/metabolismo , Equidae , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/patogenicidade , Feminino , Microbiologia de Alimentos , Lactação/fisiologia , Leuconostoc mesenteroides/química , Leuconostoc mesenteroides/metabolismo , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Listeria monocytogenes/patogenicidade , Testes de Sensibilidade Microbiana , Leite/microbiologia , Marrocos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/patogenicidade
5.
Sensors (Basel) ; 21(21)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34770507

RESUMO

The challenge today is to optimize agriculture water consumption and minimize leaching of pollutants in agro-ecosystems in order to ensure a sustainable agriculture. The use of different technologies and the adoption of different irrigation strategies can facilitate efficient fertigation management. In this respect, the determination of soil field capacity point is of utmost importance. The use of a portable weighing lysimeter allows an accurate quantification of crop water consumption and water leaching, as well as the detection of soil field capacity point. In this work, a novel algorithm is developed to obtain the soil field capacity point, in order to give autonomy and objectivity to efficient irrigation management using a portable weighing lysimeter. The development was tested in field grown horticultural crops and proved to be useful for optimizing irrigation management.


Assuntos
Ecossistema , Solo , Agricultura , Algoritmos , Água/análise
6.
Rev Med Chil ; 149(5): 672-681, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34751319

RESUMO

Background The coronavirus disease (COVID-19) pandemic affected the prompt diagnosis and treatment of Acute myocardial infarction (AMI). AIM: To characterize the clinical profile of patients with AMI during the COVID-19 pandemic, comparing them with a historical cohort. MATERIAL AND METHODS: A case-control study of 96 patients with AMI transferred to a high-volume percutaneous coronary intervention (PCI) hospital between March and July 2020, and a historical cohort of 269 patients transferred during the same period in 2019. RESULTS: When comparing patients transferred during the pandemic with those of the historical cohort, the former were younger (63 ± 12 vs 68 ± 12 years, p < 0.01), had a higher frequency of hypertension (66 vs 45%, p < 0.01) and of smoking (40% vs 25%, p < 0.01). Also, during COVID-19 outbreak a higher proportion of patients had ST-elevation AMI consulting > 12 hours from the onset of symptoms (44 vs 0%, p < 0.01), a higher median door-to-device time (4 vs 3 hours, p < 0.01), a higher use of primary percutaneous coronary intervention (97 vs 71%, p < 0.01), and higher frequencies of cardiogenic shock (20 vs 4%, p < 0.01) and mechanical complications (10% vs 2%, p < 0.01). Patients during COVID pandemic had a higher thirty-day overall (20 vs 1.4%, p < 0.01) and cardiovascular mortality (13 vs 1%, p < 0.01). During the outbreak, 40% of patients had positive COVID-19 status, which was a predictor for thirty-day overall mortality (Risk ratio 2.90; 95% confidence intervals 1.14-7.36). CONCLUSIONS: During the pandemic patients with AMI exhibited delays in consultations and treatment, higher morbidity, and increased mortality. COVID-19 positivity was associated to worse thirty-day overall survival.


Assuntos
Angioplastia Coronária com Balão , COVID-19 , Infarto do Miocárdio , Intervenção Coronária Percutânea , Estudos de Casos e Controles , Eletrocardiografia , Humanos , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/terapia , Pandemias , Prognóstico , Reperfusão , SARS-CoV-2 , Resultado do Tratamento
7.
Scand J Clin Lab Invest ; 80(3): 179-184, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31846350

RESUMO

This prospective study aimed at investigating the influence of surgery type and perioperative sampling times on the correlations between rotational thromboelastometry (ROTEM) parameters and standard laboratory coagulation tests assessing comparable coagulation phases. Patients undergoing glioblastoma multiforme resection (GBR group, n = 60) or laparoscopic colon cancer resection (CCR group, n = 40) were prospectively included. Blood samples for ROTEM and laboratory assessments were consecutively drawn within 24-hours prior to surgery (baseline), and at 2, 24 and 48-hours after surgery. Correlations between perioperative ExTEM clotting-time (CT-exTEM) and prothrombin time (PT), and between FibTEM maximum clot firmness (MCF-fibTEM) with and plasma fibrinogen (pFB) concentration (Clauss method), were evaluated using the Spearman's rho test. The efficiency of recommended cut-offs of CT-exTEM (>75 s) and MCF-fibTEM (<10 mm) for predicting a prolonged PT (>15 s) or a low pFB (<2 g/L), respectively, was assessed using Receiver-Operator Characteristic curves. Correlations between CT-exTEM and PT were weak in GBR (rho = 0.25 [0.12-0.38], p < .01), and very weak in CCR (rho = 0.06 [-0.12-0.27]). Those between MCF-fibTEM and pFB, were strong in both GBR (rho = 0.69 [0.61-0.76], p < .01) and CCR (rho = 0.70 [0.60-0.78], p < .01). These correlations remained largely unchanged over the studied perioperative period in both groups. Recommended CT-exTEM and MCF-fibTEM cut-offs had poor sensitivity for predicting a prolonged PT (17% [8-31]) or a low pFB (46% [32-62]), without group-related differences. Neither the type of surgery nor the perioperative sampling times had a significant influence on the correlations between ROTEM parameters and standard laboratory tests. ClinicalTrials.gov ID: NCT02652897.


Assuntos
Transtornos da Coagulação Sanguínea/sangue , Coagulação Sanguínea , Neoplasias Encefálicas/sangue , Neoplasias do Colo/sangue , Glioblastoma/sangue , Idoso , Transtornos da Coagulação Sanguínea/diagnóstico , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/patologia , Neoplasias do Colo/cirurgia , Feminino , Fibrinogênio/metabolismo , Glioblastoma/diagnóstico , Glioblastoma/patologia , Glioblastoma/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Período Perioperatório , Estudos Prospectivos , Tempo de Protrombina/estatística & dados numéricos , Curva ROC , Tromboelastografia/instrumentação , Tromboelastografia/métodos
8.
Rev Med Chil ; 148(8): 1083-1089, 2020 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-33399774

RESUMO

BACKGROUND: Myocardial infarction with non-obstructive coronary artery disease (MINOCA) is common. Cardiac magnetic resonance (CMR) and intravascular imaging (IVI) may be useful for establishing its etiology. AIM: To describe a population with MINOCA and its multi-image assessment using IVI or CMR. MATERIAL AND METHODS: Review of medical records, imaging and functional studies of patients with MINOCA treated in three different clinical centers between 2015 and 2019. RESULTS: Twenty-eight patients with MINOCA and IVI were included. Seventy eight percent were women, 46% had hypertension, 32% smoked and 32% had dyslipidemia. At wall motion assessment, 46% presented apical ballooning pattern. In 36% of patients IVI identified lesions that explained the cause of MINOCA, namely plaque disruption (PD) in 18%, spontaneous coronary dissection in 11% and a thrombus without PD in 7%. Forty-six percent of patients had uncomplicated atherosclerotic plaques, and 36% had no pathological findings. CMR was performed in 50% of patients, identifying in all a diagnostic pattern. In nine cases it was compatible with stress cardiomyopathy, three cases had a myocarditis and two cases had transmural infarctions. PD and transmural late gadolinium enhancement were observed in 23% of patients with apical ballooning. Patients with a pattern of myocarditis did not have acute pathological findings at IVI. After a mean follow-up of 16.4±11.4 months, 3 patients with PD died. CONCLUSIONS: Among patients with MINOCA, there was a predominance of female gender with low cardiovascular risk factor load. The multi-image assessment allowed greater precision for etiological diagnosis of MINOCA. Apical ballooning was not pathognomonic for stress cardiomyopathy. PD was associated with mortality.


Assuntos
Doença da Artéria Coronariana , Infarto do Miocárdio , Meios de Contraste , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Feminino , Gadolínio , Humanos , Masculino , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/etiologia
9.
Chemistry ; 25(55): 12769-12779, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31287914

RESUMO

Detailed studies on hydrogen evolution by decamethylruthenocene ([Cp*2 RuII ]) highlighted that metallocenes are capable of photoreducing hydrogen without the need for an additional sensitizer. Electrochemical, gas chromatographic, and spectroscopic (UV/Vis, 1 H and 13 C NMR) measurements corroborated by DFT calculations indicated that the production of hydrogen occurs by a two-step process. First, decamethylruthenocene hydride [Cp*2 RuIV (H)]+ is formed in the presence of an organic acid. Subsequently, [Cp*2 RuIV (H)]+ is reversibly reduced in a heterolytic reaction with one-photon excitation leading to a first release of hydrogen. Thereafter, the resultant decamethylruthenocenium ion [Cp*2 RuIII ]+ is further reduced with a second release of hydrogen by deprotonation of a methyl group of [Cp*2 RuIII ]+ . Experimental and computational data show spontaneous conversion of [Cp*2 RuII ] to [Cp*2 RuIV (H)]+ in the presence of protons. Calculations highlight that the first reduction is endergonic (ΔG0 =108 kJ mol-1 ) and needs an input of energy by light for the reaction to occur. The hydricity of the methyl protons of [Cp*2 RuII ] was also considered.

10.
Sensors (Basel) ; 19(19)2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31569611

RESUMO

In this work, we demonstrated lossy mode resonance (LMR) generation in optical fiber structures based on multimode fibers coated with aluminum-doped zinc oxide (AZO) films. AZO thin films were deposited by using radio frequency magnetron sputtering. In order to exhibit the usefulness of the LMR effect for sensing applications in optical fiber based systems, the deposition conditions of the AZO film coatings were set to obtain the second LMR order within the 1.55 µm wavelength range. An optical transmission configuration setup was used to investigate the LMR effect on fiber structures based on the use of no-core and cladding-removed multimode fibers coated with AZO films synthesized from metallic sputtering targets with different proportions of Zn:Al, 92:8% and 98:2%, at atomic concentrations. The optical and electrical/chemical features of the AZO films were characterized with UV-vis and XPS spectroscopy, respectively. The optical response of the proposed sensing configuration to refractive index (RI) variations was experimentally demonstrated. For the best approach, the sensitivity of wavelength displacement to RI variations on the liquid surrounding media was found to be 1214.7 nm/RIU.

11.
Mol Genet Metab ; 125(3): 295-301, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30201327

RESUMO

Genetic variants in promoters and alternative-splicing lesions require to be experimentally tested in order to validate them as causatives of a disease. The digital PCR (dPCR) approach, which is an alternative to the classical qPCR, is an innovative and a more sensitive method for the detection and quantification of nucleic acids. In the present study, we identified four HMBS gene mutations affecting the ubiquitous isoform of porphobilinogen deaminase (PBGD) and established a dPCR protocol which would be able to detect the different transcripts of this gene. With the application of this method, we were able to characterize the functional roles of these four genetic variants, demonstrating that all these mutations were causatives of the non-erythroid variant of the acute intermittent porphyria (AIP) disease.


Assuntos
Hidroximetilbilano Sintase/genética , Porfiria Aguda Intermitente/genética , Isoformas de Proteínas/genética , Sítios de Splice de RNA/genética , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase , Porfiria Aguda Intermitente/patologia , Regiões Promotoras Genéticas/genética , Adulto Jovem
12.
BMC Cancer ; 18(1): 127, 2018 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-29394925

RESUMO

BACKGROUND: Nc886 is a 102 bp non-coding RNA transcript initially classified as a microRNA precursor (Pre-miR-886), later as a divergent homologue of the vault RNAs (vtRNA 2-1) and more recently as a novel type of RNA (nc886). Although nc886/vtRNA2-1/Pre-miR-886 identity is still controversial, it was shown to be epigenetically controlled, presenting both tumor suppressor and oncogenic function in different cancers. Here, we study for the first time the role of nc886 in prostate cancer. METHODS: Nc886 promoter methylation status and its correlation with patient clinical parameters or DNMTs levels were evaluated in TCGA and specific GEO prostate tissue datasets. Nc886 level was measured by RT-qPCR to compare normal/neoplastic prostate cells from radical prostatectomies and cell lines, and to assess nc886 response to demethylating agents. The effect of nc886 recovery in cell proliferation (in vitro and in vivo) and invasion (in vitro) was evaluated using lentiviral transduced DU145 and LNCaP cell lines. The association between the expression of nc886 and selected genes was analyzed in the TCGA-PRAD cohort. RESULTS: Nc886 promoter methylation increases in tumor vs. normal prostate tissue, as well as in metastatic vs. normal prostate tissue. Additionally, nc886 promoter methylation correlates with prostate cancer clinical staging, including biochemical recurrence, Clinical T-value and Gleason score. Nc886 transcript is downregulated in tumor vs. normal tissue -in agreement with its promoter methylation status- and increases upon demethylating treatment. In functional studies, the overexpression of nc886 in the LNCaP and DU145 cell line leads to a decreased in vitro cell proliferation and invasion, as well as a reduced in vivo cell growth in NUDE-mice tumor xenografts. Finally, nc886 expression associates with the prostate cancer cell cycle progression gene signature in TCGA-PRAD. CONCLUSIONS: Our data suggest a tumor suppressor role for nc886 in the prostate, whose expression is epigenetically silenced in cancer leading to an increase in cell proliferation and invasion. Nc886 might hold clinical value in prostate cancer due to its association with clinical parameters and with a clinically validated gene signature.


Assuntos
Epigênese Genética , Regulação Neoplásica da Expressão Gênica/genética , MicroRNAs/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/genética , Metilação de DNA , Genes Supressores de Tumor , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus
13.
Eur J Haematol ; 101(3): 368-378, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29901818

RESUMO

INTRODUCTION: Congenital dyserythropoietic anemias (CDA) are characterized by hyporegenerative anemia with inadequate reticulocyte values, ineffective erythropoiesis, and hemolysis. Distinctive morphology of bone marrow erythroblasts and identification of causative genes allow classification into 4 types caused by variants in CDAN1, c15orf41, SEC23B, KIF23, and KLF1 genes. OBJECTIVE: Identify pathogenic variants in CDA patients. METHODS: Massive parallel sequencing with a targeted gene panel, Sanger sequencing, Comparative Genome Hybridization (CGH), and in silico predictive analysis of pathogenicity. RESULTS: Pathogenic variants were found in 21 of 53 patients studied from 44 unrelated families. Six variants were found in CDAN1: two reported, p.Arg714Trp and p.Arg725Trp and, four novel, p.Arg623Trp, p.Arg946Trp, p.Phe1125Ser and p.Ser1227Gly. Twelve variants were found in SEC23B: seven reported, p.Arg14Trp, p.Glu109Lys, p.Arg217Ter, c.835-2A>G, p.Arg535Ter, p.Arg550Ter and p.Arg718Ter and, five novel, p.Val164Leu, p.Arg190Gln, p.Gln521Ter, p.Arg546Trp, and p.Arg611Gln. The variant p.Glu325Lys in KLF1 was found in one patient and p.Tyr365Cys in ALAS2 in an other. Moreover, we identified genomic rearrangements by CGH in some SEC23B-monoallelic patients. CONCLUSIONS: New technologies for genetic studies will help to find variants in other genes, in addition to those known, that contribute to or modulate the CDA phenotype or support the correct diagnosis.


Assuntos
Anemia Diseritropoética Congênita/diagnóstico , Anemia Diseritropoética Congênita/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Anemia Diseritropoética Congênita/sangue , Criança , Pré-Escolar , Hibridização Genômica Comparativa , Bases de Dados de Ácidos Nucleicos , Feminino , Estudos de Associação Genética/métodos , Variação Genética , Genótipo , Glicoproteínas/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares , Adulto Jovem
14.
Salud Publica Mex ; 60(1): 41-47, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29689655

RESUMO

OBJECTIVE: To identify and characterize Aedes aegypti's AAEL006536 gene proximal upstream cis-regulatory sequences activated by dengue virus infection. MATERIALS AND METHODS: A. aegypti Rockefeller strain mosquitoes were blood fed or infected with dengue virus 2. Open chromatinprofiling was then carried out in pools of midguts from each group of mosquitoes. RESULTS: The proximal upstream region does not contain open chromatin sites in the midguts of blood-fed mosquitoes as detected by FAIRE-qPCR. In contrast, two cis-regulatory sites were identified in the same upstream region of dengue virus-infected mosquito midguts. The distal sequence contains STAT-, REL- and C/EBP-type transcription factor binding sites. CONCLUSIONS: The activation of two proximal cis-regulatory sequences, induced by dengue virus infection, is mediated by chromatin remodeling mechanisms. Binding sites suggest a dengue virus infectioninduced participation of immunity transcription factors in the up-regulation of this gene. This suggests the participation of the AAEL006536 gene in the mosquito's antiviral innate immune response.


Assuntos
Aedes/genética , Vírus da Dengue/fisiologia , Genes de Insetos , Proteínas de Insetos/genética , Mosquitos Vetores/genética , Aedes/imunologia , Animais , Montagem e Desmontagem da Cromatina , Feminino , Regulação Viral da Expressão Gênica , Interações Hospedeiro-Patógeno , Imunidade Inata , Intestinos/virologia , Mosquitos Vetores/imunologia , Análise de Sequência de DNA
15.
Angew Chem Int Ed Engl ; 56(9): 2324-2327, 2017 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-28124825

RESUMO

The photoinduced hydrogen evolution reaction (HER) by decamethylruthenocene, Cp2 *RuII (Cp*=C5 Me5 ), is reported. The use of a metallocene to photoproduce hydrogen is presented as an alternative strategy to reduce protons without involving an additional photosensitizer. The mechanism was investigated by (spectro)electrochemical and spectroscopic (UV/Vis and 1 H NMR) measurements. The photoactivated hydride involved was characterized spectroscopically and the resulting [Cp2 *RuIII ]+ species was electrochemically regenerated in situ on a fluorinated tin oxide electrode surface. A promising internal quantum yield of 25 % was obtained. Optimal experimental conditions- especially the use of weakly coordinating solvent and counterions-are discussed.

16.
Phys Chem Chem Phys ; 18(13): 9295-304, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-26977761

RESUMO

Electrocatalysis of water oxidation was achieved using fluorinated tin oxide (FTO) electrodes modified with layer-by-layer deposited films consisting of bilayers of negatively charged citrate-stabilized IrO2 NPs and positively charged poly(diallyldimethylammonium chloride) (PDDA) polymer. The IrO2 NP surface coverage can be fine-tuned by controlling the number of bilayers. The IrO2 NP films were amorphous, with the NPs therein being well-dispersed and retaining their as-synthesized shape and sizes. UV/vis spectroscopic and spectro-electrochemical studies confirmed that the total surface coverage and electrochemically addressable surface coverage of IrO2 NPs increased linearly with the number of bilayers up to 10 bilayers. The voltammetry of the modified electrode was that of hydrous iridium oxide films (HIROFs) with an observed super-Nernstian pH response of the Ir(III)/Ir(IV) and Ir(IV)-Ir(IV)/Ir(IV)-Ir(V) redox transitions and Nernstian shift of the oxygen evolution onset potential. The overpotential of the oxygen evolution reaction (OER) was essentially pH independent, varying only from 0.22 V to 0.28 V (at a current density of 0.1 mA cm(-2)), moving from acidic to alkaline conditions. Bulk electrolysis experiments revealed that the IrO2/PDDA films were stable and adherent under acidic and neutral conditions but degraded in alkaline solutions. Oxygen was evolved with Faradaic efficiencies approaching 100% under acidic (pH 1) and neutral (pH 7) conditions, and 88% in alkaline solutions (pH 13). This layer-by-layer approach forms the basis of future large-scale OER electrode development using ink-jet printing technology.

17.
Neurocrit Care ; 24(3): 371-80, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26627227

RESUMO

BACKGROUND: This 3-year prospective study examined the association between red blood cell transfusion (RBCT) and 1-year neurocognitive and disability levels in 309 patients with traumatic brain injury (TBI) admitted to the neurological intensive care unit (NICU). METHODS: Using a telephone interview-based survey, functional outcomes were assessed by the Glasgow Outcome Scale (GOS), Rancho Los Amigos Levels of Cognitive Functioning Scale (RLCFS), and Disability Rating Scale (DRS) and dichotomized as favorable and unfavorable (dependent variable). The adjusted influence of RBCT on unfavorable results was assessed by conventional logistic regression, controlling for illness severity and propensity score (introduced as a continuous variable and by propensity score-matched patients). RESULTS: Overall, 164 (53 %) patients received ≥1 unit of RBCT during their NICU stay. One year postinjury, transfused patients exhibited significantly higher unfavorable GOS (46.0 vs. 22.0 %), RLCFS (37.4 vs. 15.4 %), and DRS (39.6 vs. 18.7 %) scores than nontransfused patients. Although transfused patients were more severely ill upon admission, their adjusted odds ratios (95 % confidence intervals) for unfavorable GOS, RLCFS, and DRS scores were 2.5 (1.2-5.1), 3.0 (1.4-6.3), and 2.3 (1.1-4.8), respectively. These odds ratios remained largely unmodified when the calculated propensity score was incorporated as an independent continuous variable into the multivariate analysis. Furthermore, in 76 pairs of propensity score-matched patients, the rate of an unfavorable RLCFS score at the 1-year (but not 6-month) follow-up was significantly higher in transfused than nontransfused patients [3.0 (1.1-8.2)]. CONCLUSION: Our results strongly suggest an independent association between RBCT and unfavorable long-term functional outcomes of patients with TBI.


Assuntos
Lesões Encefálicas Traumáticas/terapia , Disfunção Cognitiva/diagnóstico , Transfusão de Eritrócitos/métodos , Avaliação de Resultados em Cuidados de Saúde , Índice de Gravidade de Doença , Adulto , Idoso , Lesões Encefálicas Traumáticas/complicações , Disfunção Cognitiva/etiologia , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
18.
Rev Med Chil ; 144(12): 1617-1620, 2016 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-28393998

RESUMO

We report a 23-year-old woman, with three recent exertional syncopes. Transthoracic (TTE) and transesophageal (TEE) echocardiography found a large heterogeneous mass (38 x 35 mm) arising from the posterior mitral annulus, protruding in systole through the left ventricular outflow tract (LVOT). Heart MRI confirmed the echocardiography findings, suggesting a cardiac myxoma. Cardiac surgery accomplished the complete resection of the lesion, confirming a mass arising from the posterior mitral annulus and preserving mitral anatomy and function. Pathology was positive for a myxoma. Uneventful evolution allowed the discharge of the patient at the fifth postoperative day. Control TTE discarded any complication.


Assuntos
Neoplasias Cardíacas/complicações , Valva Mitral , Mixoma/complicações , Síncope/etiologia , Diagnóstico Diferencial , Ecocardiografia Transesofagiana , Feminino , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/patologia , Humanos , Mixoma/diagnóstico , Mixoma/patologia , Adulto Jovem
19.
Proc Natl Acad Sci U S A ; 109(29): 11558-63, 2012 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-22665787

RESUMO

The photochemical reactivity of osmocene in a biphasic water-organic solvent system has been investigated to probe its water splitting properties. The photoreduction of aqueous protons to hydrogen under anaerobic conditions induced by osmocene dissolved in 1,2-dichloroethane and the subsequent water splitting by the osmocenium metal-metal dimer formed during H(2) production were studied by electrochemical methods, UV-visible spectrometry, gas chromatography, and nuclear magnetic resonance spectroscopy. Density functional theory computations were used to validate the reaction pathways.


Assuntos
Eletroquímica/métodos , Hidrogênio/química , Compostos Organometálicos/química , Fotoquímica , Energia Solar , Água/química , Cromatografia Gasosa , Dicloretos de Etileno , Espectroscopia de Ressonância Magnética , Modelos Químicos , Oxirredução , Oxigênio/química , Espectrofotometria Ultravioleta
20.
J Am Chem Soc ; 136(45): 15845-8, 2014 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-25325162

RESUMO

The complex [Ru(Mebimpy)(4,4'-((HO)2OPCH2)2bpy)(OH2)](2+) surface bound to tin-doped indium oxide mesoporous nanoparticle film electrodes (nanoITO-Ru(II)(OH2)(2+)) is an electrocatalyst for the selective oxidation of methylrhenium trioxide (MTO) to methanol in acidic aqueous solution. Oxidative activation of the catalyst to nanoITO-Ru(IV)(OH)(3+) induces oxidation of MTO. The reaction is first order in MTO with rate saturation observed at [MTO] > 12 mM with a limiting rate constant of k = 25 s(-1). Methanol is formed selectively in 87% Faradaic yield in controlled potential electrolyses at 1.3 V vs NHE. At higher potentials, oxidation of MTO by nanoITO-Ru(V)(O)(3+) leads to multiple electrolysis products. The results of an electrochemical kinetics study point to a mechanism in which surface oxidation to nanoITO-Ru(IV)(OH)(3+) is followed by direct insertion into the rhenium-methyl bond of MTO with a detectable intermediate.

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