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1.
Materials (Basel) ; 17(10)2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38793334

RESUMO

The global presence of pharmaceutical pollutants in water sources represents a burgeoning public health concern. Recent studies underscore the urgency of addressing this class of emerging contaminants. In this context, our work focuses on synthesizing a composite material, FexOy/MAF-32, through a streamlined one-pot reaction process, as an adsorbent for diclofenac, an emerging environmental contaminant frequently found in freshwater environments and linked to potential toxicity towards several organisms such as fish and mussels. A thorough characterization was performed to elucidate the structural composition of the composite. The material presents magnetic properties attributed to its superparamagnetic behavior, which facilitates the recovery efficiency of the composite post-diclofenac adsorption. Our study further involves a comparative analysis between the FexOy/MAF-32 and a non-magnetic counterpart, comprised solely of 2-ethylimidazolate zinc polymer. This comparison aims to discern the relative advantages and disadvantages of incorporating magnetic iron oxide nanoparticles in the contaminant removal process facilitated by a coordination polymer. Our findings reveal that even a minimal incorporation of iron oxide nanoparticles substantially enhanced the composite's overall performance in pollutant adsorption.

2.
Emerg Infect Dis ; 29(6): 1091-1101, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37209716

RESUMO

Patients who have Lyme neuroborreliosis (LNB) might experience lingering symptoms that persist despite antibiotic drug therapy. We tested whether those symptoms are caused by maladaptive immune responses by measuring 20 immune mediators in serum and cerebrospinal fluid (CSF) in 79 LNB patients followed for 1 year. At study entry, most mediators were highly concentrated in CSF, the site of the infection. Those responses resolved with antibiotic therapy, and associations between CSF cytokines and signs and symptoms of LNB were no longer observed. In contrast, subjective symptoms that persisted after use of antibiotics were associated with increased levels of serum interferon-α (IFN-α), which were already observed at study entry, and remained increased at each subsequent timepoint. Highest IFN-α levels corresponded with severe disease. Although the infection serves as the initial trigger, sequelae after antibiotic therapy are associated with unremitting systemic IFN-α levels, consistent with the pathogenic role of this cytokine in interferonopathies in other conditions.


Assuntos
Neuroborreliose de Lyme , Humanos , Neuroborreliose de Lyme/tratamento farmacológico , Neuroborreliose de Lyme/diagnóstico , Interferon-alfa/uso terapêutico , Citocinas , Fatores Imunológicos , Antibacterianos/uso terapêutico
3.
J Fish Biol ; 103(3): 544-556, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37212715

RESUMO

The dolphinfish (Coryphaena hippurus) is a globally distributed marine predator that supports one of the most important coastal fisheries along the Eastern Tropical Pacific (ETP), but its spatial movements in this area are poorly understood. Stable isotope values (δ13 C and δ15 N) of white muscle from dolphinfish (n = 220) captured at different locations across the ETP (i.e., Mexico, Costa Rica, Ecuador, Peru and oceanic areas) were normalized to copepod baseline stable isotope values to estimate dolphinfish trophic position, movements and population dispersal. Movement or residence patterns were inferred from the difference in δ15 N values (Δ15 Ndolphinfish-copepod ‰) between copepods and dolphinfish muscle. Baseline corrected isotope values (δ13 Cdolphinfish-copepod and δ15 Ndolphinfish-copepod ) of dolphinfish muscle were used to estimate isotopic niche metrics and infer population dispersal across isoscapes. Values of δ13 C and δ15 N differed between juvenile and adult dolphinfish and across the ETP. Trophic position estimates ranged from 3.1 to 6.0 with a mean of 4.6. Adults and juveniles had similar trophic position estimates, whereas isotopic niche areas (SEA ‰2 ) of adults were greater relative to juveniles in every location. Adult dolphinfish showed "moderate movement by some individuals" in all locations based on Δ15 Ndolphinfish-copepod values, except for Costa Rica where adults were classified with "high degree of movement by some individuals" whereas juveniles showed "limited movement" in all areas except Mexico. Population dispersal based on Δ15 Ndolphinfish-copepod values showed "moderate" and "high" dispersal for adults and "no dispersal" for most juveniles, except for Mexico. This study provides insight into potential dolphinfish spatial mobility across an area of interest for multiple nations, which can help to improve stock assessments and management of the species.


Assuntos
Copépodes , Perciformes , Animais , Carbono , Isótopos de Nitrogênio , Músculos , Pesqueiros , Isótopos de Carbono
4.
Nanomaterials (Basel) ; 12(9)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35564210

RESUMO

In this research, changes in several characteristics of partially reduced titania were studied. The reduction process used made it possible to gradually observe changes in the material depending on the amount of reducing agent used. We used NaBH4 to impregnate commercial TiO2 with isopropyl alcohol. Impregnated TiO2 nanoparticles were dried and thermally treated in a nitrogen flow to obtain blue titania samples. Thorough spectroscopic characterization showed that oxygen atoms from hydroxyl groups, as well as from the surface, and the lattice of TiO2 was consumed. This caused changes in the surface and even in the bulk of TiO2 when the amount of reducing agent used was increased. Structural, optical, superficial, and textural characteristics were studied using XRD, Raman, DRS UV-Vis-NIR, Mid-DRIFT, XPS, and nitrogen adsorption/desorption isotherms. A photocatalytic test of the degradation of methylene blue dye was performed. Among different effects on the mentioned characteristics, we found evidence of changes in the surface properties of the blue titania samples and their probable effect on the photocatalytic properties. The reduction process implied a preponderant decrease in the surface hydrophilicity of the reduced samples, an effect shown for the first time in this type of material.

5.
Emerg Infect Dis ; 28(4)2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35318928

RESUMO

Lyme neuroborreliosis (LNB) in Europe may manifest with painful meningoradiculoneuritis (also known as Bannwarth syndrome) or lymphocytic meningitis with or without cranial neuritis (peripheral facial palsy). We assessed host immune responses and the prevalence of TLR1 (toll-like receptor 1)-1805GG polymorphism to gain insights into the pathophysiology of these conditions. Regardless of LNB manifestation, most mediators associated with innate and adaptive immune responses were concentrated in cerebrospinal fluid; serum levels were unremarkable. When stratified by specific clinical manifestation, patients with meningoradiculoneuritis had higher levels of B-cell chemoattractants CXC motif chemokine ligand (CXCL) 12 and CXCL13 and T-cell-associated mediators CXCL9, CXCL10, and interleukin 17, compared with those without radicular pain. Moreover, these patients had a higher frequency of TLR1-1805GG polymorphism and more constitutional symptoms. These findings demonstrate that meningoradiculoneuritis is a distinct clinical entity with unique immune and genetic pathophysiology, providing new considerations for the study of LNB and borrelial meningoradiculitis.


Assuntos
Borrelia , Citocinas , Paralisia Facial , Neuroborreliose de Lyme , Quimiocinas/metabolismo , Citocinas/metabolismo , Europa (Continente) , Humanos , Neuroborreliose de Lyme/líquido cefalorraquidiano , Neuroborreliose de Lyme/diagnóstico , Neuroborreliose de Lyme/genética , Prevalência
6.
Trop Med Infect Dis ; 5(3)2020 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-32842560

RESUMO

(1) Background: Infections caused by Toxocara canis and T. cati are considered zoonoses of global importance. Reports from North and South America indicate that human infections are widespread in both continents, but epidemiological information from Central America is still lacking. (2) Methodology: In the present cross-sectional multi-year study, we aimed to undertake the first seroepidemiological and environmental study on toxocariasis in Honduras. This included the determination of seroprevalence of anti-Toxocara spp. antibodies in children using a Toxocara spp. purified excretory-secretory antigens enzyme-linked immunosorbent assay (TES-ELISA) and a confirmatory Western blot. As well, through statistical analysis including logistic regression we aimed at identifying relevant biological and epidemiological factors associated with seropositivity. The study also entailed detection of parasites' eggs in the soil samples both through Sheather's concentration method and a nested polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. (3) Results: The study was undertaken in a coastal community of Honduras in 2 different years, 2015 and 2017. A total of 88 healthy schoolchildren completed the study, with participation of 79% (73/92) and 65% (46/71) of the student body in 2015 and 2017, respectively. Thirty-one children participated in both years (i.e., dual participants). Through both serological tests, seropositivity was confirmed in 88.6% (78/88) of children. Due to the high number of seropositives, logistic regression analysis was not possible for most socio-economic and epidemiological variables. Eosinophilia, on the other hand, was associated with seropositivity, independently of other intestinal helminthic infections. Continued seropositivity was observed in most of the dual participants, while seroconversion was determined in 8 of these children. Microscopic examination of soil samples did not yield any positive results. Through nested PCR-RFLP, 3 of the 50 samples (6%) were positive for Toxocara spp.; two were identified as T. canis and one as T. cati. (4) Conclusions: This work documents for the first time, high levels of human exposure to Toxocara spp. in Honduras. These findings, along with the country's favorable epidemiological conditions for this zoonosis, emphasize the need for more research to determine whether this infection is underreported in the country.

7.
RSC Adv ; 10(64): 39251-39260, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-35518399

RESUMO

Zeolites are not often used directly as photocatalysts. Their framework and nanocavities have served as support or hosts for photoactive materials or traces of transition metals functioning as photoactive sites for catalysing decomposition and oxidation reactions in the gas phase. Research in this area has been limited to a few synthetic zeolites and in this context, efforts are directed to the preparation of new zeolite-based photocatalysts, when in nature there is an abundance of materials with properties yet to be discovered. We report the application of a natural clinoptilolite-mordenite zeolite as an efficient self-photocatalytic material for the decomposition of caffeine in aqueous solution. Adsorption experiments, combined with textural, crystallographic, and spectroscopic characterization were performed comparatively for the natural zeolite, a synthetic homologue, and the iron-exchanged zeolite. The neat zeolite containing 1.2 wt% of endogenous iron exhibited 99% decomposition of caffeine after 4 h irradiation and a faster reaction rate, followed by the synthetic sample. In contrast, the iron-loaded sample was the less effective zeolite because of pore blocking. Caffeine adsorption occurred on the outer zeolite surface and the photoproducts were hydroxylated pyrimidine rings and linear amide derivatives.

8.
Cienc. tecnol. salud ; 6(1): 43-52, 2019. ^c27 cmilus
Artigo em Espanhol | LILACS | ID: biblio-1025512

RESUMO

La prevalencia de desnutrición en niños en Guatemala es constante y se ha mantenido alta por años. Tomando en cuenta esta problemática se planteó un modelo de alimentación complementaria a base de yogur enriquecido con harinas de alto valor proteico en niños de edad preescolar en el suroccidente de Guatemala. Los tratamientos evaluados fueron yogur con harina de Acheta domesticus (grillo), yogur con harina de Brosimum alicastrum Swartz (ramón) y un grupo control. Se evaluó el peso, talla y velocidad de crecimiento durante cuatro meses brindando 125 mL de yogur cinco días por semana. La ganancia media (desviación estándar) de peso en kg fue de 3.21 (1.84), 2.22 (1.14) y 1.67 (0.64) para A. domesticus, B. alicastrum y grupo control, respectivamente. Mostrando la mezcla de yogur con harina de A. domesticus diferencia significativa frente al control (p < .05), por el contrario, no se encontró diferencia significativa (p > .05) cuando se comparó con yogur con harina de B. alicastrum. Para el incremento en talla en cm los resultados fueron 4.61 (1.13), 4.25 (1.54) y 3.07 (1.84) para A. domesticus, B. alicastrum y grupo control, respectivamente, mostrando ambas diferencias significativas frente al control (p < .05). Se determinaron los costos por dosis los cuales fueron US$0.56 (A. domesticus) y US$0.36 (B. alicastrum). Se concluye que el yogur con harina de A. domesticus fue el que presentó mejor respuesta en las variables de estudio.


The prevalence data on malnutrition of children in Guatemala are constant. Taking into account this problem, a yogurt-based supplementary feeding model was proposed, enriched with high-protein flours in pre-school children in southwestern Guatemala. The treatments evaluated were yogurt with Acheta domesticus flour (cricket), yogurt with Brosimum alicastrum Swartz flour (ramon) and control group. The weight, height and growth rate were evaluated during four months providing 125 mL of yogurt five days per week. The weight gain in kg was 3.21 (1.84), 2.22 (1.14) and 1.67 (0.64) for A. domesticus, B. alicastrum and control group respectively, showing significant difference (p < .05). The costs per dose were determined, which were US $ 0.56 (A. domesticus) and US $ 0.36 (B. alicastrum). The study concludes that yogurt with A. domesticus flour was the one that presented the best response in the study variables.


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Iogurte/análise , Alimentos Fortificados/análise , Gryllidae , Alimentos Fortificados/economia , Desnutrição/prevenção & controle , Farinha
9.
J Hazard Mater ; 263 Pt 1: 73-83, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23972666

RESUMO

Carbon-TiO2 sulfated composites were obtained from TiOSO4 · xH2O and glycerol as the TiO2 and carbon sources, respectively. The precursor xerogels were prepared in a one-step ultrasonic-assisted sol-gel reaction, followed by thermal treatment at 400°C under a nitrogen atmosphere to produce carbon-TiO2 sulfated composites. XRD, micro-Raman, SEM, and TEM studies showed that the composites consisted of nanocrystalline clusters of TiO2 and carbon. Ultrasonication in glycerol promoted the crystallinity of the xerogel precursors prior to thermal treatment. X-ray powder diffraction and Raman spectroscopy studies confirmed that glycerol also facilitated the formation of small crystallites. The band gaps of carbon-TiO2 composites with two different carbon loadings were found to be 3.06 eV and 2.69 eV. By contrast, the band gap of TiO2 prepared by our method was 3.53 eV. Calcination of the precursors led to an unusual increase in the specific surface and porosity of the composites compared to TiO2. The photocatalytic activities of the prepared composites were tested in a decomposition assay of Acid Orange 7. The reaction was monitored by UV-vis spectrophotometry and by LC-ESI-(Qq)-TOF-MS-DAD. Some intermediate species were identified by LC-ESI-QTOF-MS.


Assuntos
Carbono/química , Nanopartículas Metálicas/química , Titânio/química , Compostos Azo/química , Benzenossulfonatos/química , Catálise , Corantes/química , Glicerol/química , Temperatura Alta , Nanopartículas Metálicas/efeitos da radiação , Fotólise , Sonicação , Titânio/efeitos da radiação , Raios Ultravioleta
10.
Hypertension ; 42(1): 56-60, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12810754

RESUMO

In studies on carotid artery intima-media thickness and stroke, researchers implicitly assume that cerebrovascular abnormalities show a symmetrical distribution. To evaluate whether there is a difference in intima-media thickness between the 2 carotids, we compared left and right common carotid artery intima-media thickness as measured by B-mode ultrasonography in a group of 102 untreated hypertensive patients. This yielded a significant difference between both sides (left, 0.75+/-0.11 mm; right, 0.71+/-0.11 mm; P<0.001). This was associated with a higher cross-sectional area of the intima-media complex and a higher flow velocity at the left side. Arterial diameters, however, were not different. We also assessed whether there is a side preference with respect to cerebrovascular accidents. To this end, we explored our population-based Stroke Registry of 1843 subjects and indeed found a significantly higher incidence of nonlacunar cerebrovascular stroke at the left side, whereas lacunar infarcts were symmetrically distributed. Our findings suggest a predilection for cerebrovascular disease at the left side, which may be related to greater hemodynamic stress and intimal damage in the left carotid artery.


Assuntos
Artéria Carótida Primitiva/diagnóstico por imagem , Hipertensão/complicações , Acidente Vascular Cerebral/etiologia , Adulto , Idoso , Artéria Carótida Primitiva/anatomia & histologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Acidente Vascular Cerebral/classificação , Acidente Vascular Cerebral/epidemiologia , Túnica Íntima/diagnóstico por imagem , Túnica Média/diagnóstico por imagem , Ultrassonografia
11.
Alergia (Méx.) ; 37(2): 53-8, mar.-abr. 1990. ilus
Artigo em Espanhol | LILACS | ID: lil-95450

RESUMO

Se presentan 4 casos clínicos con esta patología, en pacientes de más de 40 años, de predominio en el sexo femenino, cuyos síntomas principales fueron rinorrea y cefalea. El origen de esta entidad puede ser post traumática, post quirúrgica o espontánea. La rinorrea de líquido cefalorraquideo es una enfermedad poco frecuente en nuestro medio y cuando se diagnostica debe ser tratada en forma multidisciplinaria.


Assuntos
Humanos , Adulto , Pessoa de Meia-Idade , Masculino , Feminino , Rinorreia de Líquido Cefalorraquidiano , Rinorreia de Líquido Cefalorraquidiano/classificação , Rinorreia de Líquido Cefalorraquidiano/fisiopatologia , Mielografia
12.
Alergia (Méx.) ; 37(2): 69-74, mar.-abr. 1990. ilus
Artigo em Espanhol | LILACS | ID: lil-95452

RESUMO

Se utilizaron al azar dos grupos de 30 pacientes con diagnóstico de rinitis y/o asma alérgicas, para conocer la sensibilidad y especificidad del multitest en el diagnóstico de tales enfermedades, comparado con las pruebas intradérmicas y Rast, a siete alergenos más comunes de esta zona, y el grado de aceptación de los pacientes. Al evaluar la preferencia del paciente, la mayoría prefirió multitest porque les dolió menos (p=0.000001); sin embargo, la prueba intradérmica demostró tener mayor sensibilidad y especificidad corroborando por Rast que multitest cuando se evaluaron polvo (P=000001) y dermatophagoides farinae (P>0.01), aunque no hubo diferencias con los otros alergenos y el testigo. Nosotros concluimos que el multiest es un método de diagnóstico útil, seguro y confiable para evaluar la respuesta alérgica en los pacientes; sin embargo, cuando el cuadro clínico sea sugestivo de alergia y el mutitest sea negativo, deberán practicarse pruebas intradérmicas.


Assuntos
Humanos , Adolescente , Adulto , Pessoa de Meia-Idade , Alérgenos , Hipersensibilidade/diagnóstico , Testes Intradérmicos/instrumentação , Teste de Radioalergoadsorção
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