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1.
Environ Sci Technol ; 57(41): 15499-15510, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37795960

RESUMO

Hyporheic zones (HZs)─zones of groundwater-surface water mixing─are hotspots for dissolved organic matter (DOM) and nutrient cycling that can disproportionately impact aquatic ecosystem functions. However, the mechanisms affecting DOM metabolism through space and time in HZs remain poorly understood. To resolve this gap, we investigate a recently proposed theory describing trade-offs between carbon (C) and nitrogen (N) limitations as a key regulator of HZ metabolism. We propose that throughout the extent of the HZ, a single process like aerobic respiration (AR) can be limited by both DOM thermodynamics and N content due to highly variable C/N ratios over short distances (centimeter scale). To investigate this theory, we used a large flume, continuous optode measurements of dissolved oxygen (DO), and spatially and temporally resolved molecular analysis of DOM. Carbon and N limitations were inferred from changes in the elemental stoichiometric ratio. We show sequential, depth-stratified relationships of DO with DOM thermodynamics and organic N that change across centimeter scales. In the shallow HZ with low C/N, DO was associated with the thermodynamics of DOM, while deeper in the HZ with higher C/N, DO was associated with inferred biochemical reactions involving organic N. Collectively, our results suggest that there are multiple competing processes that limit AR in the HZ. Resolving this spatiotemporal variation could improve predictions from mechanistic models, either via more highly resolved grid cells or by representing AR colimitation by DOM thermodynamics and organic N.


Assuntos
Ecossistema , Água Subterrânea , Carbono/metabolismo , Nitrogênio/análise , Água Subterrânea/química , Matéria Orgânica Dissolvida , Respiração , Rios/química
2.
Chemosphere ; 342: 140132, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37690560

RESUMO

In this work, complete elimination of Escherichia coli and Salmonella typhimurium was achieved in 120 min using a heterogeneous photo-Fenton process under sunlight at pH 6.5 in distilled water. A face-centered composite central design 22 with one categoric factor and three replicates at the central point was used to evaluate the effect of iron (III) oxide concentration (0.8-3.4 mg L-1), H2O2 (2-10 mg L-1), and the type of iron oxide phase (maghemite and hematite) on the inactivation of both bacteria. The results showed that the amount of catalyst, H2O2 concentration and their interaction were significant factors (p < 0.05) in the elimination of the microorganisms. Thus, under the best conditions (3.4 mg L-1 of iron (III) oxide and 10 mg L-1 of H2O2) in the experimental ranges, complete inactivation of E. coli and S. typhimurium was achieved (6-log reduction) in 120 min using the photo-Fenton treatment with both iron-oxide phases. Furthermore, the photocatalytic elimination of both bacteria by the photo-Fenton process using hematite and maghemite in secondary-treated wastewater effluent was performed obtaining slower inactivation rates (1.2-5.9 times) than in distilled water due to the matrix effect of the effluent from a wastewater treatment plant. Nevertheless, the process continued to be effective in the effluent, achieving complete bacterial elimination in 150 min using the hematite phase. Additionally, the SEM images of the bacterial cells showed that the heterogeneous photo-Fenton treatment generated permanent and irreversible cell damage, resulting in complete cell death.


Assuntos
Escherichia coli , Purificação da Água , Luz Solar , Águas Residuárias , Salmonella typhimurium , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/química , Desinfecção/métodos , Ferro/farmacologia , Ferro/química , Purificação da Água/métodos , Água/farmacologia , Oxirredução
3.
J Am Chem Soc ; 145(37): 20588-20594, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37683101

RESUMO

This manuscript describes skeletal isomerization strategies to install one to four quaternary germanium atoms in the sila-adamantane core, in a cluster analogy to precision germanium doping in silicon-germanium alloys. The first strategy embodies an inorganic variant of single-atom skeletal editing, where we use a sila-Wagner-Meerwein bond shift cascade to exchange a peripheral Ge atom with a core Si atom. We can install up to four Ge atoms at the quaternary diamondoid centers based on controlling the SixGey stoichiometry of our precursor. We find that bridgehead Ge centers can be selectively functionalized over bridgehead Si centers in SiGe adamantanes; we use this chemistry in conjunction with scanning tunneling microscopy break-junction (STM-BJ) measurements to show that Si8Ge2 adamantane wires give a 60% increase in single-molecule conductance compared with Si10 adamantanes. These studies describe the first quantum transport measurements in sila-diamondoid structures, and demonstrate how main-chain Ge doping can be used to increase electronic transmission in sila-diamondoid-based molecular wires.

4.
Ground Water ; 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37776269

RESUMO

This note describes the development and testing of a novel, programmable reversing flow 1D (R1D) experimental column apparatus designed to investigate reaction, sorption, and transport of solutes in aquifers within dynamic reversing flow zones where waters with different chemistries mix. The motivation for constructing this apparatus was to understand the roles of mixing and reaction on arsenic discharging through a tidally fluctuating riverbank. The apparatus can simulate complex transient flux schedules similar to natural flow regimes The apparatus uses an Arduino microcontroller to control flux magnitude through two peristaltic pumps. Solenoid valves control flow direction from two separate reservoirs. In-line probes continually measure effluent electrical conductance, pH, oxidation-reduction potential, and temperature. To understand how sensitive physical solute transport is to deviations from the real hydrograph of the tidally fluctuating river, two experiments were performed using: (1) a simpler constant magnitude, reversing flux direction schedule (RCF); and (2) a more environmentally relevant variable magnitude, reversing flux direction schedule (RVF). Wherein, flux magnitude was ramped up and down according to a sine wave. Modeled breakthrough curves of chloride yielded nearly identical dispersivities under both flow regimes. For the RVF experiment, Peclet numbers captured the transition between diffusion and dispersion dominated transport in the intertidal interval. Therefore, the apparatus accurately simulated conservative, environmentally relevant mixing under transient, variable flux flow regimes. Accurately generating variable flux reversing flow regimes is important to simulate the interaction between flow velocity and chemical reactions where Brownian diffusion of solutes to solid-phase reaction sites is kinetically limited.

5.
Cir Cir ; 91(3): 388-396, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37433151

RESUMO

BACKGROUND: The acquired brain damage is a common neurological disorder. OBJECTIVE: Determine the probabilistic intersections of variables related to acquired brain damage from the determination of a priori and a posteriori probabilities. METHOD: Analytical retrospective study. A descriptive analysis was carried out, confidence intervals were calculated to obtain the mean and the proportion with α = 0.05 considering the age of the patient and the diagnosis. An analysis of probabilistic intersection, a priori and a posteriori probability was performed considering diagnosis, sex and age decade; finally, chi squared was calculated. RESULTS: 736 patients were analyzed. The most frequent diagnosis was language disorder. The patients diagnosed with memory disorder were the youngest and those diagnosed with degenerative cognitive disorder the oldest. The probability that a patient with sequelae due to acquired brain damage arrives at the hospital, at the language pathology service, to be diagnosed with a language disorder and that this patient is also a man is 29.06%. CONCLUSIONS: The high prevalence of short and long-term disability generated by acquired brain damage highlights the importance of an early and timely detection and diagnosis so that it favors prompt and efficient specialized care.


ANTECEDENTES: El daño cerebral adquirido es un trastorno neurológico común. OBJETIVO: Determinar las intersecciones probabilísticas de variables relacionadas con daño cerebral adquirido a partir de la determinación de probabilidades a priori y a posteriori. MÉTODO: Estudio retrospectivo analítico. Se realizó análisis descriptivo y se calcularon intervalos de confianza para la media y para la proporción con α = 0.05 considerando la edad del paciente y el diagnóstico. Se realizó análisis de intersección probabilística, probabilidad a priori y a posteriori considerando el diagnóstico, el sexo y la década de edad; por último, se utilizó la prueba χ2. RESULTADOS: Se analizaron 736 pacientes. El diagnóstico más frecuente fue el trastorno del lenguaje. Los pacientes diagnosticados con trastorno de memoria fueron los más jóvenes y los diagnosticados con trastorno cognitivo degenerativo los más longevos. La probabilidad de que llegue al hospital, al servicio de patología de lenguaje, un paciente con secuelas por daño cerebral adquirido, sea diagnosticado con trastorno del lenguaje y sea hombre es del 29.06%. CONCLUSIONES: La alta prevalencia de discapacidad a corto y largo plazo generada por el daño cerebral adquirido indica la importancia de la detección y el diagnóstico temprano y oportuno que favorezcan una pronta y eficiente atención especializada.


Assuntos
Lesões Encefálicas , Transtornos Cognitivos , Transtornos da Linguagem , Masculino , Humanos , Estudos Retrospectivos , Lesões Encefálicas/etiologia , Progressão da Doença , Transtornos da Linguagem/etiologia
6.
Semergen ; 49(8): 102066, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-37517163

RESUMO

BACKGROUND AND OBJECTIVES: Previous studies that quantify the cost of type 2 diabetes (DM2) show very different results. We set out to define the profile of the patient with DM2 in Andalusia, analyze the use of health resources and quantify their economic cost during 2022. PATIENTS AND METHODS: Multicenter, cross-sectional and descriptive study. Three hundred and eighty-five patients with DM2 from Andalusia (confidence level: 95%; error: 5%). DATA ANALYZED: age, sex, attendance at primary care (PC), nursing, emergency and hospital specialty consultations; consumption of drugs in general and antidiabetics in particular, blood glucose strips, complementary tests and hospitalization days. RESULTS: Mean age: 70.7 ± 12.44 years; 53.6% men. Care contacts: PC physician: 8.36 ± 4.69; nursing: 7.17 ± 12; hospital visits: 2.31 ± 2.38; emergencies: 1.71 ± 2.89; hospitalization days: 2.26 ± 6.46. LABORATORY TESTS: 3.79 ± 5.45 and 2.17 ± 3.47 Rx. Drugs consumed: 9.20 ± 3.94 (1.76 ± 0.90 antidiabetics). Blood glucose strips: 184 ± 488. Annual cost: 5171.05 €/patient/year (2228.36 € for hospital admissions, 1702.87 € for drugs and 1239.82 € for assistance and complementary tests). CONCLUSIONS: The DM2 Andalusian is 71 years old, consumes 10 different drugs and treats DM2 with double therapy. He has been 20 attendances/year (75% in PC), 4 analyses, 2 X-rays and requires 2 days of hospitalization. Direct healthcare costs goes over 5000 €/year. This represents 41.66% of the budget of the Andalusian Ministry of Health and triples the average cost per habitant.


Assuntos
Diabetes Mellitus Tipo 2 , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glicemia , Estudos Transversais , Hipoglicemiantes/uso terapêutico , Custos de Cuidados de Saúde
7.
Benef Microbes ; 14(2): 153-164, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-36856122

RESUMO

Dysbiosis has been implicated in childhood obesity. Oral intake of fermented milk containing Lacticaseibacillus casei strain Shirota preserves gut microbiota (GM) diversity in children and adults. This study was a double-blind trial involving 37 overweight or obese children aged 6-10 years. Children were followed over a 6-week intervention period in which they received different fermented milk products containing L. casei Shirota: 10 in the first group received just L. casei Shirota; 13 received L. casei Shirota with 3 g/day of inulin (L. casei+inulin); and 14 received L. casei Shirota with 3 g/day of fructans from Agave salmiana (L. casei+fructans). Principal component analysis showed the relationship between microbial abundance, GM metabolites, and other obesity-related markers. Supplementation with probiotics and synbiotics improved the HDL-cholesterol levels of overweight and obese children, although no changes in body composition were detected. We observed an increase in butyrate or propionate concentrations in the L. casei+fructans group compared to the end of the intervention (P<0.03). A diminished level of ANGPTL4 within the L. casei+fructans group (P=0.04) was also found, but no differences when lipopolysaccharide-binding protein was evaluated. The FFAR2+ cell frequency decreased between baseline and at the end of 6-week intervention in L. casei+inulin (P=0.02) and L. casei+fructans groups (P=0.04). In contrast, the percentage of CD14+FFAR3+ frequency increased in the same groups (P=0.04). The L. casei Shirota with inulin or fructans modulates GM, which improves the lipid profile and changes at a molecular level, such as expression of FFAR3 and FFAR2, ANGPTL4, propionate, and butyrate. It, therefore, could be considered an interesting therapeutic possibility for treating childhood overweight and obesity. The study was registered at ClinicalTrials.gov (ID: NCT05423015).


Assuntos
Agave , Produtos Fermentados do Leite , Obesidade Infantil , Probióticos , Criança , Adulto , Humanos , Frutanos , Agave/química , Inulina/farmacologia , Sobrepeso/tratamento farmacológico , Obesidade Infantil/tratamento farmacológico , Propionatos , Biomarcadores
8.
Rev. otorrinolaringol. cir. cabeza cuello ; 83(1): 9-14, mar. 2023. ilus, graf
Artigo em Espanhol | LILACS | ID: biblio-1431947

RESUMO

Introducción: Pese a que el uso de corticoides transtimpánicos en pacientes con enfermedad de Méniere es habitual en muchos centros, la evidencia respecto de su efecto sobre los umbrales auditivos es aún controversial. Objetivo: Estudiar los umbrales auditivos de pacientes con enfermedad de Méniere que recibieron corticoides transtimpánicos en el Servicio de Otorrinolaringología del Hospital Clínico de la Universidad de Chile. Material y Método: Estudio retrospectivo de pacientes con enfermedad de Méniere que consultaron entre los años 2015 y 2021. Se estudiaron los umbrales auditivos, antes y después de 3 inyecciones de dexametasona transtimpánica. Resultados: Se obtuvieron datos completos de 27 pacientes. Al comparar el promedio tonal puro antes y después del tratamiento, no se observaron diferencias significativas. A nivel individual, la variación de cambio de los umbrales auditivos con dexametasona se correlaciona en forma significativa con los umbrales auditivos previos a las inyecciones y con el tiempo transcurrido desde la última inyección, pero no con la edad. Conclusión: La terapia con dexametasona transtimpánica en pacientes con enfermedad de Méniere no altera los umbrales auditivos. Sin embargo, se requieren más estudios, para comprobar, si existe un efecto transitorio en los umbrales auditivos de los primeros días posterior al procedimiento.


Introduction: Although transtympanic corticosteroids are proposed in Méniere's disease patients refractory to standard medical therapy, the evidence regarding the effect of transtympanic corticosteroids on hearing thresholds is still controversial. Aim: To study the hearing thresholds of patients with Méniere's disease who were administrated with transtympanic corticosteroids at the Otorhinolaryngology Service of the University of Chile's Clinical Hospital. Material and Method: Retrospective study of Méniere's disease patients who consulted between 2015 and 2021. Demographic variables and hearing thresholds were studied before and after three transtympanic injections of dexamethasone. Results: A total of 27 patients were studied. There were non-significant differences in pure-tone hearing threshold averages before and after the injections. Individual variation in hearing thresholds correlates significantly with the pre-injection hearing thresholds and the period since the last injection, but not with age. Conclusion: Transtympanic dexamethasone therapy in patients with Meniere's disease does not alter hearing thresholds. However, more studies are needed to verify whether there is a transitory effect on hearing thresholds in the first days after the procedure.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Limiar Auditivo/efeitos dos fármacos , Dexametasona/uso terapêutico , Doença de Meniere/tratamento farmacológico , Anti-Inflamatórios/uso terapêutico , Audiometria/métodos , Chile , Estudos Retrospectivos
9.
Rev Neurol ; 76(5): 167-175, 2023 03 01.
Artigo em Espanhol | MEDLINE | ID: mdl-36843177

RESUMO

INTRODUCTION: Palliative care refers to treatment aimed at the early and comprehensive identification of pain and other physical, psychosocial and spiritual problems that limit the quality of life of the person, their family and their caregivers. The aim of this article is to identify palliative interventions used for the assessment and control of symptoms in people with advanced Parkinson's disease (PD). MATERIALS AND METHODS: A systematic review of the literature was conducted following the steps proposed by Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The search was guided by a structured review question and included original studies of patients with advanced PD published in databases such as Medline and Google Scholar between 2010 and 2021. RESULTS: Thirty-one full-text studies were reviewed and 12 were excluded due to not meeting quality criteria. A total of 19 papers were included in this systematic review, which identified 10 clinical tools to assess palliative needs in advanced PD, four pharmacological interventions, and three non-pharmacological interventions focused on reducing motor symptoms, improving quality of life and avoiding the on/off state. One study reported the referral of patients to complementary and device-assisted therapies. CONCLUSION: As part of the palliative approach, a set of tools for identifying symptoms and assessing palliative care needs have been described. Interventions in advanced PD focus on the control of motor and non-motor symptoms so as to reduce the impact of the disease on quality of life.


TITLE: Cuidados paliativos para personas con enfermedad de Parkinson avanzada. Revisión sistemática.Introducción. Los cuidados paliativos hacen referencia al tratamiento dirigido a la identificación precoz e impecable del dolor y otros problemas físicos, psicosociales y espirituales que limitan la calidad de vida de la persona, la familia y sus cuidadores. El objetivo de este artículo es identificar las intervenciones paliativas utilizadas para la valoración y el control de síntomas en personas con enfermedad de Parkinson (EP) avanzada. Materiales y métodos. Se desarrolló una revisión sistémica de la bibliografía aplicando los pasos propuestos por Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). La búsqueda se orientó a partir de una pregunta de revisión estructurada y se incluyeron estudios originales de pacientes con EP avanzada publicados en bases de datos como Medline y Google Scholar entre 2010 a 2021. Resultados. Se revisaron 31 estudios en texto completo y se excluyeron 12 estudios por no alcanzar los criterios de calidad. En total, se incluyeron 19 trabajos en esta revisión sistemática, identificando 10 herramientas clínicas para valorar las necesidades paliativas en EP avanzada, cuatro intervenciones farmacológicas, y tres intervenciones no farmacológicas centradas en disminuir síntomas motores, mejorar la calidad de vida y evitar el estado on/off. Un estudio notificó la derivación del paciente a terapias complementarias y asistidas por dispositivos. Conclusión. Como parte del abordaje paliativo se han descrito un conjunto de herramientas para identificar síntomas y valorar necesidades de atención paliativa. Las intervenciones en la EP avanzada se enfocan en el control de los síntomas motores y no motores para disminuir el impacto de la enfermedad sobre la calidad de vida.


Assuntos
Cuidados Paliativos , Doença de Parkinson , Humanos , Qualidade de Vida , Doença de Parkinson/terapia , Dor , Cuidadores
10.
J Contam Hydrol ; 251: 104068, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36108569

RESUMO

Shallow (<30 m) reducing groundwater commonly contains abundant dissolved arsenic (As) in Bangladesh. We hypothesize that dissolved As in iron (Fe)-rich groundwater discharging to rivers is trapped onto Fe(III)-oxyhydroxides which precipitate in shallow riverbank sediments under the influence of tidal fluctuations. Therefore, the goal of this study is to compare the calculated mass of sediment-bound As that would be sequestered from dissolved groundwater As that discharges through riverbanks of the Meghna River to the observed mass of As trapped within riverbank sediments. To calculate groundwater discharge, a Boussinesq aquifer analytical groundwater flow model was developed and constrained by cyclical seasonal fluctuations in hydraulic heads and river stages observed at three sites along a 13 km reach in central Bangladesh. At all sites, groundwater discharges to the river year-round but most of it passes through an intertidal zone created by ocean tides propagating upstream from the Bay of Bengal in the dry season. The annualized groundwater discharge per unit width at the three sites ranges from 173 to 891 m2/yr (average 540 m2/yr). Assuming that riverbanks have been stable since the Brahmaputra River avulsed far away from this area 200 years ago and dissolved As is completely trapped within riverbank sediments, the mass of accumulated sediment As can be calculated by multiplying groundwater discharge by ambient aquifer As concentrations measured in 1969 wells. Across all sites, the range of calculated sediment As concentrations in the riverbank is 78-849 mg/kg, which is higher than the observed concentrations (17-599 mg/kg). This discovery supports the hypothesis that the dissolved As in groundwater discharge to the river is sufficient to account for the observed buried deposits of As along riverbanks.


Assuntos
Arsênio , Água Subterrânea , Poluentes Químicos da Água , Arsênio/análise , Rios , Sedimentos Geológicos , Compostos Férricos , Poluentes Químicos da Água/análise , Monitoramento Ambiental
11.
Chemosphere ; 308(Pt 2): 136289, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36058378

RESUMO

Elevated dissolved arsenic (As) concentrations in the shallow aquifers of Bangladesh are primarily caused by microbially-mediated reduction of As-bearing iron (Fe) (oxy)hydroxides in organic matter (OM) rich, reducing environments. Along the Meghna River in Bangladesh, interactions between the river and groundwater within the hyporheic zone cause fluctuating redox conditions responsible for the formation of a Fe-rich natural reactive barrier (NRB) capable of sequestering As. To understand the NRB's impact on As mobility, the geochemistry of riverbank sediment (<3 m depth) and the underlying aquifer sediment (up to 37 m depth) was analyzed. A 24-hr sediment-water extraction experiment was performed to simulate interactions of these sediments with oxic river water. The sediment and the sediment-water extracts were analyzed for inorganic and organic chemical parameters. Results revealed no differences between the elemental composition of riverbank and aquifer sediments, which contained 40 ± 12 g/kg of Fe and 7 ± 2 mg/kg of As, respectively. Yet the amounts of inorganic and organic constituents extracted were substantially different between riverbank and aquifer sediments. The water extracted 6.4 ± 16.1 mg/kg of Fe and 0.03 ± 0.02 mg/kg of As from riverbank sediments, compared to 154.0 ± 98.1 mg/kg of Fe and 0.55 ± 0.40 mg/kg of As from aquifer sediments. The riverbank and aquifer sands contained similar amounts of sedimentary organic matter (SOM) (17,705.2 ± 5157.6 mg/kg). However, the water-extractable fraction of SOM varied substantially, i.e., 67.4 ± 72.3 mg/kg in riverbank sands, and 1330.3 ± 226.6 mg/kg in aquifer sands. Detailed characterization showed that the riverbank SOM was protein-like, fresh, low molecular weight, and labile, whereas SOM in aquifer sands was humic-like, older, high molecular weight, and recalcitrant. During the dry season, oxic conditions in the riverbank may promote aerobic metabolisms, limiting As mobility within the NRB.


Assuntos
Arsênio , Água Subterrânea , Poluentes Químicos da Água , Arsênio/análise , Bangladesh , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Água Subterrânea/química , Ferro/análise , Compostos Orgânicos , Rios , Areia , Água , Poluentes Químicos da Água/análise
13.
Angew Chem Int Ed Engl ; 61(31): e202206877, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35605045

RESUMO

The first syntheses of functionalized sila-adamantanes via site-selective reactions are described. Mechanistic inquiry into the isomerization of sila-adamantane revealed new approaches for installing halides at the 2-position of the cluster. Meanwhile, isomerization via Lewis acid catalysts with non-nucleophilic counteranions provided access to sila-adamantane on the gram-scale, enabling us to discover strategies for substituting its 1-, 3-, 5-, and 7-positions with identical or distinct functional groups. Optical absorbance and density functional theory studies show that σ-withdrawing substituents at the 1-position strongly perturb optical absorbance in sila-adamantane, whereas substituents at the exocyclic and 2-position are optically inert. As silicon diamondoids are atomically precise models for silicon nanocrystals, our findings suggest that passivation at tertiary surface sites carries an outsized impact on the optical properties of surface-functionalized Si nanocrystals.

14.
Semin Arthritis Rheum ; 53: 151940, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35051890

RESUMO

OBJECTIVE: There is a well-recognized association between cancer and myositis, so cancer screening at diagnosis is recommended. We aim to report the results of our cancer screening strategy and to ascertain the reliability of using PET/CT to identify cancer-associated myositis (CAM) in a large cohort of patients with myositis from a single center over 10 years. METHODS: This retrospective observational study included all patients diagnosed with any type of myositis except for inclusion body myositis. Cancer screening strategy was individualized according to clinical and serological data, including PET/CT as the main test to detect occult cancer (OC). Procedures derived from a positive PET/CT were registered. Qualitative data expressed as percentages, and quantitative data as the median with the interquartile range were analyzed. A ROC curve was used to estimate the reliability of PET/CT for CAM diagnosis. RESULTS: Seventy-seven out of 131 patients underwent a PET/CT for OC screening. The performance of the PET/CT in patients with myositis at disease onset yielded an area under the curve ROC of 0.87 (0.73-0.97) for CAM diagnosis. Invasive procedures in 7 (9%) patients without a final diagnosis of cancer did not cause derived complications. Patients not evaluated for OC did not develop cancer after a median follow-up of 3.3 years (1.7-6.7). CONCLUSION: Cancer screening strategy should be individualized. PET/CT at myositis onset seems to be an efficient approach to rule out CAM. This practice does not seem to significantly increase harm to patients related to the additional tests needed to clarify inconclusive results.


Assuntos
Miosite , Neoplasias , Detecção Precoce de Câncer , Humanos , Miosite/diagnóstico , Miosite/diagnóstico por imagem , Neoplasias/complicações , Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Reprodutibilidade dos Testes , Estudos Retrospectivos
15.
Int J Food Microbiol ; 363: 109510, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-34974282

RESUMO

This study evaluated the antifungal effect of ZnO nanoparticles (ZnO-NPs) on Fusarium proliferatum growth and fumonisin accumulation both on a maize-based medium (in vitro) and on irradiated maize grains (in situ). The ZnO-NPs were obtained by drop-by-drop synthesis without further thermal treatment and characterized by scanning electronic microscopy/ energy dispersive X-ray spectroscopy (SEM/EDS) and X-ray diffraction (XRD). SEM analysis showed them as thin flakes of 200 × 200 nm, ~30 nm thickness and its purity were confirmed by XRD. During the in vitro assay ZnO-NPs (0, 0.8; 4, 8 g L-1) were evaluated at 25 °C during 21 days under darkness or photoperiod incubation (12/12 h light (cold white and black fluorescent lamps)/darkness) to determine its possible photocatalytic influence. Fumonisins were detected by high performance liquid chromatography coupled to mass spectrometry (HPLC- MS/MS). All ZnO-NPs concentrations significantly affected growth rates and FB1 accumulation by F. proliferatum RCFP 5033 (p < 0.05). Similar reduction of growth and FB1 (%) was observed at 0.8 and 8 g L-1 ZnO-NPs under photoperiod or darkness incubation. FB1 reduction was observed after 14 and 21 days, although the highest reduction occurred after 14 days under photoperiod incubation (84-98%). No clear light enhancing effect on the antifungal and anti-mycotoxin capability of the ZnO-NPs was observed. Morphological alterations in mycelia and conidia were observed by SEM. Under the in situ assay, the effect of the ZnO-NPs (0, 0.4, 0.8, 2 g kg-1) on growth rates and fumonisin B1, B2 and B3 accumulation by two F. proliferatum strains was evaluated on irradiated maize grains adjusted to 0.995, 0.98 and 0.97 aW in darkness at 25 °C during 21 days. Also, zinc acetate at 0.8 g kg-1 was included to compare their antifungal effect against the same ZnO-NPs concentration. Growth rates decreased significantly as ZnO-NPs concentrations increased. Higher than 60% of growth reduction was observed for both F. proliferatum strains. Zinc acetate significantly reduced growth, although it was less efficient that the same ZnO-NPs concentration. ZnO-NPs reduced total fumonisins accumulation by 71-99% at 0.8-2 g kg-1 ZnO-NPs and 0.98-0.995 aW. Moreover, 0.4 g kg-1 ZnO-NPs also produced significant reduction of the 3 fumonisins. This study showed the application of ZnO-NPs in maize grains could be a low cost and environmental impact strategy to control phytopathogen and toxigenic fungi such as F. proliferatum and to reduce fumonisins accumulation, both during crop development at preharvest stage and during maize storage.


Assuntos
Fumonisinas , Fusarium , Óxido de Zinco , Espectrometria de Massas em Tandem , Zea mays , Óxido de Zinco/farmacologia
16.
Biochem Biophys Rep ; 27: 101064, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34307907

RESUMO

HdeA is an acid-stress chaperone that operates in the periplasm of various strains of pathogenic gram-negative bacteria. Its primary function is to prevent irreversible aggregation of other periplasmic proteins when the bacteria enter the acidic environment of the stomach after contaminated food is ingested; its role is therefore to help the bacteria survive long enough to enter and colonize the intestines. The mechanism of operation of HdeA is unusual in that this helical homodimer is inactive when folded at neutral pH but becomes activated at low pH after the dimer dissociates and partially unfolds. Studies with chemical reducing agents previously suggested that the intramolecular disulfide bond is important for maintaining residual structure in HdeA at low pH and may be responsible for positioning exposed hydrophobic residues together for the purpose of binding unfolded client proteins. In order to explore its role in HdeA structure and chaperone function we performed a conservative cysteine to serine mutation of the disulfide. We found that, although residual structure is greatly diminished at pH 2 without the disulfide, it is not completely lost; conversely, the mutant is almost completely random coil at pH 6. Aggregation assays showed that mutated HdeA, although less successful as a chaperone than wild type, still maintains a surprising level of function. These studies highlight that we still have much to learn about the factors that stabilize residual structure at low pH and the role of disulfide bonds.

17.
Arch. cardiol. Méx ; 91(1): 17-24, ene.-mar. 2021. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1152856

RESUMO

Resumen Introducción: El ecocardiograma es el método de referencia para el diagnóstico del conducto arterioso permeable (CAP) hemodinámicamente significativo (CAP-hs) del recién nacido prematuro (RNP). El péptido natriurético tipo B (BNP) puede ser útil en el diagnóstico y el manejo del CAP-hs. Objetivo: Evaluar la utilidad del BNP como marcador de sobrecarga hemodinámica del conducto arterioso permeable en el RNP con edad gestacional < 32 semanas o peso < 1500 gramos, e identificar el mejor punto de corte para los valores de BNP que mejor prediga un CAP con repercusión hemodinámica que requiera tratamiento farmacológico o quirúrgico. Método: Estudio retrospectivo, observacional y descriptivo de RNP < 32 semanas de gestación o peso < 1500 gramos en los que se realizó ecocardiograma y determinación del BNP. Análisis de muestra global y por subgrupos, en función del CAP-hs. Resultados: Se analizaron 29 pacientes. Se encontró una correlación significativa entre la relación CAP/peso y los valores del BNP (prueba de Spearman: 0.71; intervalo de confianza del 95%: 0.45-0.87; p < 0.001). El mejor punto de corte del BNP para predecir CAP-hs fue 486.5 pg/ml, con una sensibilidad del 81% y una especificidad del 92% (p < 0.001). Conclusión: El punto de corte del BNP identificado en el presente estudio se correlacionó con la presencia de CAP-hs.


Abstract Introduction: The echocardiogram is the gold standard, in the diagnosis of the hemodynamically significant patent ductus arteriosus (hs-PDA) of the premature newborn (PNB). Type B natriuretic peptide (BNP) may be useful in the diagnosis and management of CAP-hs. Objective: To assess the utility of BNP as a marker of hemodynamic overload of the patent ductus arteriosus in newborns with gestational age < 32 weeks or weight < 1500 grams, and to identify the best cut-off point for BNP levels that would best predict a PDA with hemodynamic impact requiring pharmacological and/or surgical treatment. Methods: Retrospective, observational and descriptive study of PNB < 32 weeks gestation or weight < 1500 grams, in which echocardiogram and BNP determination was performed. Analysis of the global sample and by subgroups, depending on the hs-PDA status was performed. Results: A total of 29 patients were analyzed. A significant correlation was found between the PDA/weight ratio and BNP levels (Spearman: 0.71; 95% confidence interval: 0.45-0.87; p < 0.001). The best BNP cut-off point to predict CAP-hs was 486.5 pg/ml with a sensitivity of 81% and specificity of 92% (p < 0.001). Conclusion: The BNP cut-off point identified in the present study was correlated with the presence of CAP-hs.


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Peptídeo Natriurético Encefálico/sangue , Permeabilidade do Canal Arterial/fisiopatologia , Permeabilidade do Canal Arterial/sangue , Hemodinâmica , Recém-Nascido Prematuro , Biomarcadores/sangue , Estudos Retrospectivos
18.
Occup Med (Lond) ; 71(2): 99-104, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33598694

RESUMO

BACKGROUND: Head injuries are common injury in the fire service; however, very little data exist on the risks this may pose to the development of post-traumatic stress disorder (PTSD) and depression in this high-risk population. AIMS: Our study aimed to compare levels of PTSD and depression symptoms in firefighters with a line-of-duty head injury, non-line-of-duty head injury and no head injury. METHODS: In this cross-sectional study, we assessed current PTSD and depression symptoms as well as retrospective head injuries. RESULTS: Seventy-six per cent of the total sample reported at least one head injury in their lifetime. Depression symptoms were significantly more severe among firefighters with a line-of-duty head injury compared to those with no head injury, but not compared to those who sustained a non-line-of-duty head injury. Depression symptoms did not differ between firefighters with a non-line-of-duty head injury and those with no head injury. PTSD symptoms were significantly more severe among firefighters with a line-of-duty head injury compared to both firefighters with no head injury and those with a non-line-of-duty head injury. CONCLUSIONS: We found that firefighters who reported at least one line-of-duty head injury had significantly higher levels of PTSD and depression symptoms than firefighters who reported no head injuries. Our findings also suggest head injuries sustained outside of fire service could have less of an impact on the firefighter's PTSD symptom severity than head injuries that occur as a direct result of their job.


Assuntos
Traumatismos Craniocerebrais , Bombeiros , Angústia Psicológica , Transtornos de Estresse Pós-Traumáticos , Traumatismos Craniocerebrais/complicações , Traumatismos Craniocerebrais/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Depressão/etiologia , Humanos , Estudos Retrospectivos , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/etiologia
19.
Cancer Treat Rev ; 93: 102142, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33453566

RESUMO

Urothelial bladder cancer (UC) is the most common malignancy involving the urinary system and represents a significant health problem. Immunotherapy has been used for decades for UC with intravesical bacillus Calmette-Guérin (BCG) set as the standard of care for non-muscle-invasive bladder cancer (NMIBC). The advent of immune checkpoint inhibitors (ICIs) has completely transformed the treatment landscape of bladder cancer enabling to expand the treatment strategies. Novel ICIs have successfully shown improved outcomes on metastatic disease to such an extent that the standard of care paradigm has changed leading to the development of different trials with the aim of determining whether ICIs may have a role in early disease. The localized muscle-invasive bladder cancer (MIBC) scenario remains challenging since the recurrence rate continues to be high despite all therapeutic efforts. This article will review the current experience of ICIs in the neoadjuvant setting of UC, the clinical trials landscape and finally, an insight of what to expect in the immediate and mid-term future.


Assuntos
Neoplasias da Bexiga Urinária/terapia , Humanos , Imunoterapia/métodos , Terapia Neoadjuvante/métodos , Invasividade Neoplásica/prevenção & controle , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/terapia
20.
Rev. chil. pediatr ; 91(6): 982-990, dic. 2020. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1508061

RESUMO

Desde la aparición de la pandemia por SARS-CoV-2, la población pediátrica ha sido menos afectada por la enfermedad tanto en frecuencia como en severidad. Sin embargo, desde abril de este año se han reportado casos de presentación y gravedad variables, caracterizados por fenómenos inflamato rios que afectan múltiples órganos, condición denominada Síndrome Inflamatorio Multisistémico Pediátrico (PIMS). La literatura describe frecuente compromiso cardíaco, hasta en un 80%. Este se caracteriza por injuria miocárdica con significativa elevación de biomarcadores: Troponinas séricas I/T, BNP o NT-ProBNP, unido a diversos grados de disfunción ventricular, pericarditis, valvulitis y arritmias. Además, se ha evidenciado la presencia de compromiso coronario el cual puede ocurrir hasta en un 23% de los casos, en un rango que va desde dilataciones hasta aneurismas. El seguimien to cardiológico hospitalizado y ambulatorio se ha sistematizado en base a los fenotipos clínicos de presentación: injuria miocárdica (miocarditis, valvulitis, pericarditis), shock (habitualmente de tipo "vasopléjico"), manifestaciones tipo Enfermedad de Kawasaki y aquellos casos PIMS que no cumplen con la clínica de los tres precedentes. Este último grupo es el que representa el mayor desafío en el cor to, mediano y seguimiento a largo plazo. Por esta razón se requiere un equipo multidisciplinario para su manejo. Considerando la alta frecuencia del compromiso cardíaco en el PIMS y la importancia de lograr un consenso en su manejo y seguimiento, se presentan estas recomendaciones según el estado actual del conocimiento de esta patología recientemente descrita.


Since the onset of the SARS-CoV-2 pandemic, the pediatric population has been less affected by the disease both in frequency and severity. However, since April cases of variable presentation and severity characterized by inflammatory phenomena that affect multiple organs have been reported, a condition called Multisystem Inflammatory Syndrome in Children (MIS-C). The literature has reported frequent cardiac involvement, up to 80%. This is characterized by myocardial injury with a significant increase of biomarkers such as serum troponins I and T, BNP, or NT-ProBNP coupled with varying degrees of ventricular dysfunction, pericarditis, valvulitis, and arrhythmias. Coronary compromise has also been described, which can occur in up to 23% of cases, and ranges from dila tations to aneurysms. Inpatient and outpatient cardiology follow-up has been systematized based on the clinical phenotypes such as myocardial injury (myocarditis, valvulitis, pericarditis), shock (usua lly vasoplegic), Kawasaki disease-type manifestations, and those MIS-C that do not comply with the clinic of the previous three. This last group represents the main challenge in the short-, medium- and long-term follow-up, therefore, it is necessary a multidisciplinary team for managing these patients. Considering the high frequency of cardiac compromise in MIS-C, and the importance of reaching a consensus regarding its management and follow-up, we present these recommendations according to the current state of knowledge regarding this recently described pathology.


Assuntos
Humanos , Criança , Doenças Cardiovasculares/virologia , Síndrome de Resposta Inflamatória Sistêmica/terapia , COVID-19/terapia , Equipe de Assistência ao Paciente/organização & administração , Choque/terapia , Choque/virologia , Biomarcadores/metabolismo , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/terapia , Chile , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico , Síndrome de Resposta Inflamatória Sistêmica/fisiopatologia , COVID-19/diagnóstico , COVID-19/fisiopatologia , Síndrome de Linfonodos Mucocutâneos/terapia , Síndrome de Linfonodos Mucocutâneos/virologia
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