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1.
Pediatr Dermatol ; 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38444084

RESUMO

PIK3CA-related overgrowth spectrum (PROS) encompasses different clinical entities caused by somatic activating mutations in PIK3CA. Among PROS, CLOVES syndrome represents a severe phenotype with poor survival rate. We present the case of a 4-month-old girl with CLOVES syndrome successfully treated with alpelisib, a PIKC3A inhibitor.

2.
Clin Anat ; 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38469730

RESUMO

Current advances in the management of the autonomic nervous system in various cardiovascular diseases, and in treatments for pain or sympathetic disturbances in the head, neck, or upper limbs, necessitate a thorough understanding of the anatomy of the cervicothoracic sympathetic trunk. Our objective was to enhance our understanding of the origin and distribution of communicating branches and visceral cervicothoracic sympathetic nerves in human fetuses. This was achieved through a comprehensive topographic systematization of the branching patterns observed in the cervical and upper thoracic ganglia, along with the distribution of communicating branches to each cervical spinal nerve. We conducted detailed sub-macroscopic dissections of the cervical and thoracic regions in 20 human fetuses (40 sides). The superior and cervicothoracic ganglia were identified as the cervical sympathetic ganglia that provided the most communicating branches on both sides. The middle and accessory cervical ganglia contributed the fewest branches, with no significant differences between the right and left sides. The cervicothoracic ganglion supplied sympathetic branches to the greatest number of spinal nerves, spanning from C5 to T2 . The distribution of communicating branches to spinal nerves was non-uniform. Notably, C3 , C4 , and C5 received the fewest branches, and more than half of the specimens showed no sympathetic connections. C1 and C2 received sympathetic connections exclusively from the superior ganglion. Spinal nerves that received more branches often did so from multiple ganglia. The vertebral nerve provided deep communicating branches primarily to C6 , with lesser contributions to C7 , C5 , and C8 . The vagus nerve stood out as the cranial nerve with the most direct sympathetic connections. The autonomic branching pattern and connections of the cervicothoracic sympathetic trunk are significantly variable in the fetus. A comprehensive understanding of the anatomy of the cervical and upper thoracic sympathetic trunk and its branches is valuable during autonomic interventions and neuromodulation. This knowledge is particularly relevant for addressing various autonomic cardiac diseases and for treating pain and vascular dysfunction in the head, neck, and upper limbs.

3.
Inorg Chem ; 59(14): 10048-10058, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32589405

RESUMO

Metal oxyfluorides are currently attracting much attention for next-generation rechargeable batteries because of their high theoretical capacity and resulting high energy density. Rhombohedral VO2F is promising because it allows two-electron transfer during electrochemical lithium cycling, with a theoretical capacity of 526 mAh g-1. However, the chemical changes it undergoes during operation are not clearly understood. In this work, a combination of synchrotron X-ray and neutron diffraction was employed to accurately describe the crystal structure of both pristine and lithiated VO2F, using samples with high crystallinity to overcome challenges in previous studies. The mechanism and reversibility of the lithium insertion was monitored in real time by high angular synchrotron diffraction measurements, performed in operando on a lithium battery in the high-voltage range: 3.9-2.3 V vs Li+/Li. Insertion of up to one lithium ion proceeds through a solid-solution reaction, while Rietveld refinements of neutron powder diffraction data revealed that the lithiated states adopt the noncentrosymmetric R3c framework, uncovering an octahedral Li-(O/F)6 coordination with reasonable Li-O/F bond lengths. This work further evaluates the redox changes of VO2F upon Li intercalation. By a comparison of changes in electronic states of all the elements in the compound, it clarifies the critical role of both anions, O and F, in the charge compensation through their covalent interactions with the 3d states of V. The clear evidence of participation of F challenges existing assumptions that its high electronegativity renders this anion largely a spectator in the redox reaction.

4.
Mol Ther ; 26(4): 1137-1153, 2018 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-29503198

RESUMO

The Sleeping Beauty (SB) transposon system is a non-viral gene delivery platform that combines simplicity, inexpensive manufacture, and favorable safety features in the context of human applications. However, efficient correction of hematopoietic stem and progenitor cells (HSPCs) with non-viral vector systems, including SB, demands further refinement of gene delivery techniques. We set out to improve SB gene transfer into hard-to-transfect human CD34+ cells by vectorizing the SB system components in the form of minicircles that are devoid of plasmid backbone sequences and are, therefore, significantly reduced in size. As compared to conventional plasmids, delivery of the SB transposon system as minicircle DNA is ∼20 times more efficient, and it is associated with up to a 50% reduction in cellular toxicity in human CD34+ cells. Moreover, providing the SB transposase in the form of synthetic mRNA enabled us to further increase the efficacy and biosafety of stable gene delivery into hematopoietic progenitors ex vivo. Genome-wide insertion site profiling revealed a close-to-random distribution of SB transposon integrants, which is characteristically different from gammaretroviral and lentiviral integrations in HSPCs. Transplantation of gene-marked CD34+ cells in immunodeficient mice resulted in long-term engraftment and hematopoietic reconstitution, which was most efficient when the SB transposase was supplied as mRNA and nucleofected cells were maintained for 4-8 days in culture before transplantation. Collectively, implementation of minicircle and mRNA technologies allowed us to further refine the SB transposon system in the context of HSPC gene delivery to ultimately meet clinical demands of an efficient and safe non-viral gene therapy protocol.


Assuntos
Elementos de DNA Transponíveis , Técnicas de Transferência de Genes , Vetores Genéticos/genética , Células-Tronco Hematopoéticas/metabolismo , Animais , Sobrevivência Celular , Citometria de Fluxo , Expressão Gênica , Humanos , Camundongos , Camundongos Knockout , Retroviridae/genética , Transfecção , Transgenes
5.
Chemphyschem ; 17(7): 1062-9, 2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-26805439

RESUMO

Titanium-oxide-based materials are considered attractive and safe alternatives to carbonaceous anodes in Li-ion batteries. In particular, the ramsdellite form TiO2 (R) is known for its superior lithium-storage ability as the bulk material when compared with other titanates. In this work, we prepared V-doped lithium titanate ramsdellites with the formula Li0.5 Ti1-x Vx O2 (0≤x≤0.5) by a conventional solid-state reaction. The lithium-free Ti1-x Vx O2 compounds, in which the ramsdellite framework remains virtually unaltered, are easily obtained by a simple aqueous oxidation/ion-extraction process. Neutron powder diffraction is used to locate the Li channel site in Li0.5 Ti1-x Vx O2 compounds and to follow the lithium extraction by difference-Fourier maps. Previously delithiated Ti1-x Vx O2 ramsdellites are able to insert up to 0.8 Li(+) per transition-metal atom. The initial gravimetric capacities of 270 mAh g(-1) with good cycle stability under constant current discharge conditions are among the highest reported for bulk TiO2 -related intercalation compounds for the threshold of one e(-) per formula unit.

6.
Angew Chem Int Ed Engl ; 53(48): 13220-4, 2014 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-25267410

RESUMO

Controlling the synthesis of stable metal nanoparticles in water is a current challenge in nanochemistry. The strategy presented herein uses sulfonated N-heterocyclic carbene (NHC) ligands to stabilize platinum nanoparticles (PtNPs) in water, under air, for an indefinite time period. The particles were prepared by thermal decomposition of a preformed molecular Pt complex containing the NHC ligand and were then purified by dialysis and characterized by TEM, high-resolution TEM, and spectroscopic techniques. Solid-state NMR studies showed coordination of the carbene ligands to the nanoparticle surface and allowed the determination of a (13)C-(195)Pt coupling constant for the first time in a nanosystem (940 Hz). Additionally, in one case a novel structure was formed in which platinum(II) NHC complexes form a second coordination sphere around the nanoparticle.

7.
Lancet Reg Health Am ; 21: 100487, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37155483

RESUMO

Background: Policymakers urgently need evidence to adequately balance the costs and benefits of mass vaccination against COVID-19 across all age groups, including children and adolescents. In this study, we aim to assess the effectiveness of CoronaVac's primary series among children and adolescents in Chile. Methods: We used a large prospective national cohort of about two million children and adolescents 6-16 years to estimate the effectiveness of an inactivated SARS-CoV-2 vaccine (CoronaVac) in preventing laboratory-confirmed symptomatic SARS-CoV-2 infection (COVID-19), hospitalisation, and admission to an intensive care unit (ICU) associated with COVID-19. We compared the risk of individuals treated with a complete primary immunization schedule (two doses, 28 days apart) with the risk of unvaccinated individuals during the follow-up period. The study was conducted in Chile from June 27, 2021, to January 12, 2022, when the SARS-CoV-2 Delta variant was predominant but other variants of concern were co-circulating, including Omicron. We used inverse probability-weighted survival regression models to estimate hazard ratios of complete immunization over the unvaccinated status, accounting for time-varying vaccination exposure and adjusting for relevant demographic, socioeconomic, and clinical confounders. Findings: The estimated adjusted vaccine effectiveness for the inactivated SARS-CoV-2 vaccine in children aged 6-16 years was 74.5% (95% CI, 73.8-75.2), 91.0% (95% CI, 87.8-93.4), 93.8% (95% CI, 87.8-93.4) for the prevention of COVID-19, hospitalisation, and ICU admission, respectively. For the subgroup of children 6-11 years, the vaccine effectiveness was 75.8% (95% CI, 74.7-76.8) for the prevention of COVID-19 and 77.9% (95% CI, 61.5-87.3) for the prevention of hospitalisation. Interpretation: Our results suggest that a complete primary immunization schedule with the inactivated SARS-CoV-2 vaccine provides effective protection against severe COVID-19 disease for children 6-16 years. Funding: Agencia Nacional de Investigación y Desarrollo (ANID) Millennium Science Initiative Program and Fondo de Financiamiento de Centros de Investigación en Áreas Prioritarias (FONDAP).

8.
Rev Med Chil ; 140(4): 458-65, 2012 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-22854691

RESUMO

BACKGROUND: "Children with special health care needs" (CSHCN) is a novel definition for pediatric patients with chronic diseases, adopted by the Chilean Pediatric Society in 2008. As life expectancy in Chile increases, prevalence of CSHCN is progressively growing, leading to higher health costs. AIM: To describe the epidemiological profile and clinical characteristics of hospitalized CSHCN, and compare the risk assessment of adverse events during hospitalization using two definitions for CSHCN. PATIENTS AND METHODS: A cohort of hospitalized CSHCN in a Pediatric Center at Santiago, Chile, was followed from September to December 2009. Clinical and demographic data were registered in a database, including admission to intensive care unit (ICU), nosocomial infections and prolonged hospitalization (> 7 days). Incidence ratios for these events were compared between CSHCN and non-CSHCN, and between children attended by three or more health care professionals (CSHCN-3) and non-CSHCN. RESULTS: Nine hundred twenty patients were included (54% male), with a median age 14 months (0-221) and median days of hospitalization 4 days (1-229). Prevalence of CSHCN was 60.8% of hospitalized children. When using CSHCN definition and comparing with non-CSHCN, no excess of risk was documented. On the other hand, prevalence of CSHCN-3 was 19.9%. Compared to non-CSHCN, these patients had a higher risk of ICU admission (relative risk (RR) 1.58; 95% confidence intervals (CI) = 1.22-2.05; p < 0.01), nosocomial infections (RR 2.28; 95% CI = 1.54-3.39; p < 0.001) and prolonged hospitalization (RR 1.99; 95% CI = 1.52-2.60; p < 0.001). CONCLUSIONS: One in five hospitalized children met CSHCN-3 definition. These patients had an increased risk of adverse events during their hospitalization compared to non-CSHCN.


Assuntos
Serviços de Saúde da Criança , Doença Crônica/epidemiologia , Hospitais Pediátricos , Adolescente , Criança , Criança Hospitalizada/estatística & dados numéricos , Pré-Escolar , Chile/epidemiologia , Doença Crônica/classificação , Métodos Epidemiológicos , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Masculino
9.
Nat Med ; 28(7): 1377-1380, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35605637

RESUMO

The outbreak of the B.1.1.529 lineage of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (Omicron) has caused an unprecedented number of Coronavirus Disease 2019 (COVID-19) cases, including pediatric hospital admissions. Policymakers urgently need evidence of vaccine effectiveness in children to balance the costs and benefits of vaccination campaigns, but, to date, the evidence is sparse. Leveraging a population-based cohort in Chile of 490,694 children aged 3-5 years, we estimated the effectiveness of administering a two-dose schedule, 28 days apart, of Sinovac's inactivated SARS-CoV-2 vaccine (CoronaVac). We used inverse probability-weighted survival regression models to estimate hazard ratios of symptomatic COVID-19, hospitalization and admission to an intensive care unit (ICU) for children with complete immunization over non-vaccination, accounting for time-varying vaccination exposure and relevant confounders. The study was conducted between 6 December 2021 and 26 February 2022, during the Omicron outbreak in Chile. The estimated vaccine effectiveness was 38.2% (95% confidence interval (CI), 36.5-39.9) against symptomatic COVID-19, 64.6% (95% CI, 49.6-75.2) against hospitalization and 69.0% (95% CI, 18.6-88.2) against ICU admission. The effectiveness against symptomatic COVID-19 was modest; however, protection against severe disease was high. These results support vaccination of children aged 3-5 years to prevent severe illness and associated complications and highlight the importance of maintaining layered protections against SARS-CoV-2 infection.


Assuntos
COVID-19 , Vacinas Virais , COVID-19/epidemiologia , Vacinas contra COVID-19 , Criança , Pré-Escolar , Chile/epidemiologia , Surtos de Doenças/prevenção & controle , Humanos , SARS-CoV-2
10.
Materials (Basel) ; 14(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070476

RESUMO

The electrode performance and degradation of 1:1 La2-xNiTiO6-δ:YSZ composites (x = 0, 0.2) has been investigated to evaluate their potential use as SOFC cathode materials by combining electrochemical impedance spectroscopy in symmetrical cell configuration under ambient air at 1173 K, XRD, electron microscopy and image processing studies. The polarisation resistance values increase notably, i.e., 0.035 and 0.058 Ωcm2 h-1 for x = 0 and 0.2 samples, respectively, after 300 h under these demanding conditions. Comparing the XRD patterns of the initial samples and after long-term exposure to high temperature, the perovskite structure is retained, although La2Zr2O7 and NiO appear as secondary phases accompanied by peak broadening, suggesting amorphization or reduction of the crystalline domains. SEM and TEM studies confirm the ex-solution of NiO with time in both phases and also prove these phases are prone to disorder. From these results, degradation in La2-xNiTiO6-δ:YSZ electrodes is due to the formation of La2Zr2O7 at the electrode-electrolyte interface and the ex-solution of NiO, which in turn results in the progressive structural amorphization of La18NiTiO6-δ phases. Both secondary phases constitute a non-conductive physical barrier that would hinder the ionic diffusion at the La2-xNiTiO6-δ:YSZ interface and oxygen access to surface active area.

11.
Pediatrics ; 147(2)2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33414236

RESUMO

BACKGROUND: Children with neurologic impairment (NI) are at risk for developing co-occurring chronic conditions, increasing their medical complexity and morbidity. We assessed the prevalence and timing of onset for those conditions in children with NI. METHODS: This longitudinal analysis included 6229 children born in 2009 and continuously enrolled in Medicaid through 2015 with a diagnosis of NI by age 3 in the IBM Watson Medicaid MarketScan Database. NI was defined with an existing diagnostic code set encompassing neurologic, genetic, and metabolic conditions that result in substantial functional impairments requiring subspecialty medical care. The prevalence and timing of co-occurring chronic conditions was assessed with the Agency for Healthcare Research and Quality Chronic Condition Indicator system. Mean cumulative function was used to measure age trends in multimorbidity. RESULTS: The most common type of NI was static (56.3%), with cerebral palsy (10.0%) being the most common NI diagnosis. Respiratory (86.5%) and digestive (49.4%) organ systems were most frequently affected by co-occurring chronic conditions. By ages 2, 4, and 6 years, the mean (95% confidence interval [CI]) numbers of co-occurring chronic conditions were 3.7 (95% CI 3.7-3.8), 4.6 (95% CI 4.5-4.7), and 5.1 (95% CI 5.1-5.2). An increasing percentage of children had ≥9 co-occurring chronic conditions as they aged: 5.3% by 2 years, 10.0% by 4 years, and 12.8% by 6 years. CONCLUSIONS: Children with NI enrolled in Medicaid have substantial multimorbidity that develops early in life. Increased attention to the timing and types of multimorbidity in children with NI may help optimize their preventive care and case management health services.


Assuntos
Doença Crônica/epidemiologia , Doença Crônica/tendências , Medicaid/tendências , Multimorbidade/tendências , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/epidemiologia , Fatores Etários , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Estudos Retrospectivos , Estados Unidos/epidemiologia
12.
Membranes (Basel) ; 10(11)2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33212912

RESUMO

Crosslinked membranes have been synthesized by a casting process using polybenzimidazole (PBI) and poly(vinyl benzyl chloride) (PVBC). The membranes were quaternized with 1,4-diazabicyclo[2.2.2]octane (DABCO) to obtain fixed positive quaternary ammonium groups. XPS analysis has showed insights into the changes from crosslinked to quaternized membranes, demonstrating that the crosslinking reaction and the incorporation of DABCO have occurred, while the 13C-NMR corroborates the reaction of DABCO with PVBC only by one nitrogen atom. Mechanical properties were evaluated, obtaining maximum stress values around 72 MPa and 40 MPa for crosslinked and quaternized membranes, respectively. Resistance to oxidative media was also satisfactory and the membranes were evaluated in single direct ethanol fuel cell. PBI-c-PVBC/OH 1:2 membrane obtained 66 mW cm-2 peak power density, 25% higher than commercial PBI membranes, using 0.5 bar backpressure of pure O2 in the cathode and 1 mL min-1 KOH 2M EtOH 2 M aqueous solution in the anode. When the pressure was increased, the best performance was obtained by the same membrane, reaching 70 mW cm-2 peak power density at 2 bar O2 backpressure. Based on the characterization and single cell performance, PBI-c-PVBC/OH membranes are considered promising candidates as anion exchange electrolytes for direct ethanol fuel cells.

13.
Pediatrics ; 143(4)2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30914443

RESUMO

BACKGROUND AND OBJECTIVES: Little is known about the use of chronic medications (CMs) in children. We assessed the prevalence of CM use in children and the association of clinical characteristics and health care resource use with the number of CMs used. METHODS: This is a retrospective study of children ages 1 to 18 years using Medicaid from 10 states in 2014 grouped by the annual number of CMs (0, 1, 2-4, 5-9, and ≥10 medications), which are defined as a dispensed ≥30-day prescription with ≥2 dispensed refills. Trends in clinical characteristics and health care use by number of CMs were evaluated with the Cochran-Armitage trend test. RESULTS: Of 4 594 061 subjects, 18.8% used CMs. CM use was 44.4% in children with a complex chronic condition. Across all children, the most common CM therapeutic class was neurologic (28.9%). Among CM users, 48.8% used multiple CMs (40.3% used 2-4, 7.0% used 5-9, and 0.5% used ≥10). The diversity of medications increased with increasing number of CMs: for 1 CM, amphetamine stimulants were most common (29.0%), and for ≥10 CMs, antiepileptics were most common (7.1%). Of $2.3 billion total pharmacy spending, 59.3% was attributable to children dispensed multiple CMs. Increased CM use (0 to ≥10 medications) was associated with increased emergency department use (32.1% to 56.2%) and hospitalization (2.3% to 36.7%). CONCLUSIONS: Nearly 1 in 5 children with Medicaid used CMs. Use of multiple CMs was common and correlated with increased health care use. Understanding CM use in children should be fundamentally important to health care systems when strategizing how to provide safe, evidence-based, and cost-effective pharmaceutical care to children.


Assuntos
Doença Crônica/tratamento farmacológico , Custos de Medicamentos , Prescrições de Medicamentos/estatística & dados numéricos , Uso de Medicamentos/estatística & dados numéricos , Medicaid/economia , Adolescente , Fatores Etários , Criança , Pré-Escolar , Estudos de Coortes , Prescrições de Medicamentos/economia , Feminino , Custos de Cuidados de Saúde , Humanos , Lactente , Masculino , Medicaid/estatística & dados numéricos , Polimedicação , Estudos Retrospectivos , Medição de Risco , Fatores Sexuais , Estados Unidos , Populações Vulneráveis
14.
ChemSusChem ; 10(14): 2978-2989, 2017 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-28594114

RESUMO

The perovskite series Sr2 CoNb1-x Tix O6-δ (0≤x≤1) was investigated in the full compositional range to assess its potential as cathode material for solid oxide fuel cell (SOFC). The variation of transport properties and thus, the area specific resistances (ASR) are explained by a detailed investigation of the defect chemistry. Increasing the titanium content from x=0-1 produces both oxidation of Co3+ to Co4+ (from 0 up to 40 %) and oxygen vacancies (from 6.0 to 5.7 oxygen atom/formula unit), although each charge compensation mechanism predominates in different compositional ranges. Neutron diffraction reveals that samples with high Ti-contents lose a significant amount of oxygen upon heating above 600 K. Oxygen is partially recovered upon cooling as the oxygen release and uptake show noticeably different kinetics. The complex defect chemistry of these compounds, together with the compositional changes upon heating/cooling cycles and atmospheres, produce a complicated behavior of electrical conductivity. Cathodes containing Sr2 CoTiO6-δ display low ASR values, 0,13â€…Ω cm2 at 973 K, comparable to those of the best compounds reported so far, being a very promising cathode material for SOFC.


Assuntos
Condutividade Elétrica , Fontes de Energia Elétrica , Óxidos/química , Eletrodos , Oxigênio/química , Pressão , Temperatura
15.
rev. udca actual. divulg. cient ; 24(1): e1643, ene.-jun. 2021. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1290420

RESUMO

RESUMEN La acidez del suelo limita la disponibilidad, la absorción y la concentración de nutrientes y el rendimiento del cultivo de cacao. El objetivo fue evaluar el efecto del pH del suelo sobre la concentración de nutrientes en hoja, cáscara y grano, para cuatro clones de cacao autocompatibles (ICS-1, CCN-51) y autoincompatibles (ICS-39, TSH-565), en el departamento del Caquetá. El diseño experimental consistió en un arreglo factorial con cuatro clones (factor A), cuatro niveles de pH y fertilidad (factor B) y cuatro repeticiones. Los resultados indican diferencias en la concentración de nutrientes por efecto del clon y tratamiento, siendo la acumulación de N, P y Mg en grano>hoja>cáscara, K en cáscara>hoja>grano, Ca, Fe, Mn, Zn y B en hoja>cáscara>grano, S en cáscara>hoja>grano y Cu en grano>cáscara>hoja. La concentración de P, Mg y S fue mayor y, a su vez, menor Mn, cuando aumentó el pH. El orden de extracción nutrimental en grano fue N>K>P>Mg>S>Ca>Fe>Mn>Zn>Cu>B. Con relación a los clones, CCN-51 presentó habilidad para la toma de nutrientes y alcanzar mayores producciones, incluso, en suelos con pH ≥ 5,5, lo que sugiere efecto de las condiciones edafoclimáticas y, por lo tanto, la necesidad de evaluar los clones para cada zona de cultivo.


ABSTRACT The soil acidity limits availability, absorption and concentration of nutrients and yield of the cocoa crop. The objective was to evaluate the effect of soil pH on the concentration of macro and micronutrients in leaf, husk and grain for four cocoa clones, self-compatible (ICS-1, CCN-51) and self-incompatible (ICS-39, TSH-565) in the department of Caquetá. The experimental design consisted in a factorial arrangement with four clones (factor A), four pH and fertility levels (factor B) and four repetitions. The results indicate differences in the concentration of nutrients due to the effect of the clone and the treatment, being the accumulation of N, P and Mg in grain>leaf>husk, K in husk>leaf>grain, Ca, Fe, Mn, Zn y B in leaf>husk>grain, S in husk>leaf>grain and Cu in grain>husk>leaf. The concentration of P, Mg and S was higher, and in turn Mn lower, when the pH increased. The order of nutrient extraction in grain was N>K>P>Mg>S>Ca>Fe>Mn>Zn>Cu>B. Regarding clones, CCN-51 showed ability to take nutrients and reach higher productions, even in soils with pH ≥ 5.5, suggesting effect of edaphoclimatic conditions, and therefore, the need to evaluate the clones for each growing area.

16.
Rev Chilena Infectol ; 33(5): 537-542, 2016 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-28112337

RESUMO

Human respiratory syncytial virus (RSV) infection remains as a major cause of morbidity and mortality among pediatric population. Immune response is poor and unable to establish a long term effective protection against this virus. Of particular interest has been the description of extrapulmonary manifestations of RSV infection in liver, kidney, endocrine system, heart and brain, associated to infection of peripheral blood. In the central nervous system (CNS), recent studies in animals have suggested long term neurocognitive impairment due to a direct damage from the virus. This was prevented in rats by a recombinant BCG vaccine expressing a nucleoprotein N of RSV that produces an effective immune response against the virus, not allowing its dissemination to the CNS. These findings in animal models highlight the importance of conducting more specific studies in children affected with severe infection by RSV. Therefore, our group is currently conducting an assessment of the possible long-term cognitive impairment in children under 2 years. The results of this study could be a strong argument to continue looking for an effective method for protecting against RSV infection.


Assuntos
Viroses do Sistema Nervoso Central/virologia , Infecções por Vírus Respiratório Sincicial/complicações , Doença Aguda , Animais , Modelos Animais de Doenças , Humanos , Ratos , Índice de Gravidade de Doença
17.
Rev. colomb. biotecnol ; 21(1): 47-55, ene.-jun. 2019. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1013898

RESUMO

RESUMEN La producción orgánica de seda incluye la aplicación de compost como practica de cultivo en morera (Morus alba), sin embargo, el efecto de la fertilización orgánica en las poblaciones de bacterias rizosféricas no siempre es positivo. Para evaluar el efecto del compost en la diversidad de bacterias rizosféricas en cultivos de morera (Morus alba), se aplicaron 0, 0.25, 0.5 y 1 kg.m-2 de compost a parcelas con morera dispuestas en un diseño en bloques completos al azar. De cada parcela se extrajo ADN del suelo rizosférico a los 0, 5, 10 y 90 días de aplicado el compost y se amplificó la región V4 del gen ADNr 16S para su secuenciación y asignación taxonómica de los OTUS. Los índices de diversidad alpha mostraron la dominancia de algunos grupos taxonómicos, como los phyla Proteobacteria y Acidobacteria y los géneros Pseudomonas, Opitutus, Luteolibacter y Nitrospir. La diversidad beta indicó similitud entre las muestras influenciadas por la aplicación compost y el incremento de la diversidad en las parcelas muestreadas al final del experimento (90 días). Los grupos taxonómicos dominantes se caracterizan por su función en el ciclo del nitrógeno. Así, se concluyó que la aplicación de 1 kg.m-2 llevó al aumento de la humedad del suelo, el pH y la disponibilidad de nutrientes, lo que incremento la diversidad de bacterias rizosféricas con cambios positivos en composición, riqueza y abundancia en los niveles de orden, familia y género.


ABSTRACT The organic silk production includes the application of compost as cultivation practice to the mulberry crop. However, the effect of the organic fertilization on populations of rhizospheric bacteria is not always positive. To evaluate the effect of compost on the diversity of rhizospheric bacteria in mulberry crops (Morus alba), 0, 0.25, 0.5 and 1 kg.m-2 of compost was applied to mulberry plots arranged in a completely randomized blocks design. From each plot, DNA was extracted from the rhizospheric soil at 0, 5, 10 and 90 days after compost was applied and the V4 region of the 16S rDNA gene was amplified for its sequencing and taxonomic assignment of the OTUS. Alpha diversity indices showed the dominance of some taxonomic groups, such as the phyla Proteobacteria and Acidobacteria, and the genera Pseudomonas, Opitutus, Luteolibacter and Nitrospira. The beta diversity indicated similarity between the samples influenced by the compost application and the increase of the biodiversity in the plots sampled at the end of the experiment (90 days). The taxonomic groups dominated are characterized by their role in the nitrogen cycle. Thus, it was concluded that the application of 1 kg.m-2 of compost led to the increase of ground humidity, soil pH and nutrient availability which increased the rhizospheric bacteria diversity with positive changes in composition, richness and abundance at order, family and genera levels.

18.
J Med Microbiol ; 61(Pt 6): 868-873, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22383440

RESUMO

Leifsonia aquatica is an aquatic coryneform rod that is capable of forming biofilms in environmental water sources. It has rarely been associated with human infections and its pathogenicity and clinical significance are uncertain. We describe a case of catheter-related bloodstream infection in a haemodialysis patient. The isolate grew on conventional media as a yellow-pigmented colony, but identification required molecular methods. Although the strain displayed reduced sensitivity to vancomycin, the clinical outcome was favourable after catheter removal and intravenous treatment with this antibiotic. Our report gives further evidence of the capability of this aquatic bacterium to cause human infection.


Assuntos
Infecções por Actinomycetales/diagnóstico , Actinomycetales/isolamento & purificação , Bacteriemia/diagnóstico , Infecções Relacionadas a Cateter/diagnóstico , Actinomycetales/classificação , Actinomycetales/fisiologia , Infecções por Actinomycetales/microbiologia , Idoso , Bacteriemia/microbiologia , Infecções Relacionadas a Cateter/microbiologia , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Humanos , Masculino , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Diálise Renal/efeitos adversos , Análise de Sequência de DNA
19.
Dalton Trans ; 41(48): 14633-42, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-23108296

RESUMO

Li(2)Ti(6)O(13) and H(2)Ti(6)O(13) were easily synthesized from Na(2)Ti(6)O(13) by successive Na(+)-Li(+)-H(+) ion exchange. The crystal structures of Na(2)Ti(6)O(13), Li(2)Ti(6)O(13) and H(2)Ti(6)O(13) were investigated using neutron powder diffraction. Monovalent A(+) cations (Na, Li and H) have been located using difference Fourier analysis. Although monoclinic lattice parameters (space group C2/m) of the three titanates remain almost unchanged with retention of the basic [Ti(6)O(13)(2-)] network, monovalent Na, Li and H cations occupy different sites in the tunnel space. By comparing the structural details concerning the A(+) oxygen coordination, i.e. NaO(8) square prismatic coordination, LiO(4) square planar coordination and covalently bond H atoms, with results from (23)Na, (7)Li and (1)H NMR spectroscopy we were able to obtain a more detailed insight into the respective local distortions and anharmonic motions. We were able to show that the site that the A(+) cation occupies in the hexatitanate channel structure strongly influences the lithium insertion properties of these compounds and therefore their usefulness as electrode materials for energy storage.

20.
Rev. chil. infectol ; 33(5): 537-542, oct. 2016. ilus
Artigo em Espanhol | LILACS | ID: biblio-844405

RESUMO

Human respiratory syncytial virus (RSV) infection remains as a major cause of morbidity and mortality among pediatric population. Immune response is poor and unable to establish a long term effective protection against this virus. Of particular interest has been the description of extrapulmonary manifestations of RSV infection in liver, kidney, endocrine system, heart and brain, associated to infection of peripheral blood. In the central nervous system (CNS), recent studies in animals have suggested long term neurocognitive impairment due to a direct damage from the virus. This was prevented in rats by a recombinant BCG vaccine expressing a nucleoprotein N of RSV that produces an effective immune response against the virus, not allowing its dissemination to the CNS. These findings in animal models highlight the importance of conducting more specific studies in children affected with severe infection by RSV. Therefore, our group is currently conducting an assessment of the possible long-term cognitive impairment in children under 2 years. The results of this study could be a strong argument to continue looking for an effective method for protecting against RSV infection.


La infección por virus respiratorio sincicial humano (VRS) es una de las principales causas de morbimortalidad en población pediátrica. La respuesta inmune generada contra VRS es poco eficiente para su eliminación y logra establecer sólo protección parcial contra infecciones posteriores. De especial interés en los últimos años ha sido la descripción de manifestaciones extra-pulmonares de la infección por VRS en hígado, riñón, sistema endocrino, corazón y cerebro. A nivel de sistema nervioso central (SNC), estudios recientes en modelos animales han sugerido problemas neurocognitivos a largo plazo derivados de un daño directo del virus en el cerebro. Este daño logró ser prevenido con vacuna experimental BCG recombinante, que expresa la nucleoproteína N de VRS e induce inmunidad efectiva, impidiendo la diseminación del virus hacia el SNC. Estos hallazgos en modelo animal han dado cuenta de la importancia de efectuar estudios más detallados en niños afectados por VRS grave. Por tal motivo, actualmente se está realizando una evaluación de la posible alteración cognitiva a largo plazo en niños bajo dos años de edad por parte de nuestro grupo. Los resultados de este estudio podrían significar un argumento muy importante para continuar en la búsqueda de un método efectivo de protección contra esta infección.


Assuntos
Humanos , Animais , Ratos , Infecções por Vírus Respiratório Sincicial/complicações , Viroses do Sistema Nervoso Central/virologia , Índice de Gravidade de Doença , Doença Aguda , Modelos Animais de Doenças
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