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1.
Anim Microbiome ; 6(1): 36, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918824

RESUMEN

Mounting evidence of the occurrence of direct and indirect interactions between the human blood fluke, Schistosoma mansoni, and the gut microbiota of rodent models raises questions on the potential role(s) of the latter in the pathophysiology of hepatointestinal schistosomiasis. However, substantial differences in both the composition and function between the gut microbiota of laboratory rodents and that of humans hinders an in-depth understanding of the significance of such interactions for human schistosomiasis. Taking advantage of the availability of a human microbiota-associated mouse model (HMA), we have previously highlighted differences in infection-associated changes in gut microbiota composition between HMA and wildtype (WT) mice. To further explore the dynamics of schistosome-microbiota relationships in HMA mice, in this study we (i) characterize qualitative and quantitative changes in gut microbiota composition of a distinct line of HMA mice (D2 HMA) infected with S. mansoni prior to and following the onset of parasite egg production; (ii) profile local and systemic immune responses against the parasite in HMA as well as WT mice and (iii) assess levels of faecal inflammatory markers and occult blood as indirect measures of gut tissue damage. We show that patent S. mansoni infection is associated with reduced bacterial alpha diversity in the gut of D2 HMA mice, alongside expansion of hydrogen sulphide-producing bacteria. Similar systemic humoral responses against S. mansoni in WT and D2 HMA mice, as well as levels of faecal lipocalin and markers of alternatively activated macrophages, suggest that these are independent of baseline gut microbiota composition. Qualitative comparative analyses between faecal microbial profiles of S. mansoni-infected WT and distinct lines of HMA mice reveal that, while infection-induced alterations of the gut microbiota composition are highly dependent on the baseline flora, bile acid composition and metabolism may represent key elements of schistosome-microbiota interactions through the gut-liver axis.

2.
Animal ; 18(6): 101189, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38850575

RESUMEN

Laminaria digitata is a brown seaweed rich in prebiotic polysaccharides, mainly laminarin, but its alginate-rich cell wall could compromise nutrient access. Carbohydrase supplementation, such as individual alginate lyase and carbohydrases mixture (Rovabio® Excel AP), could enhance nutrient digestibility and prebiotic potential. This study aimed to evaluate the effect of these enzymes on nutrient digestibility and gut health of weaned piglets fed with 10% L. digitata. Diets did not affect growth performance (P > 0.05). The majority of the feed fractions had similar digestibility across all diets, but the supplementation of alginate lyase increased hemicellulose digestibility by 3.3% compared to the control group (P = 0.047). Additionally, we observed that algal zinc was more readily available compared to the control group, even without enzymatic supplementation (P < 0.001). However, the increased digestibility of some minerals, such as potassium, raises concerns about potential mineral imbalance. Seaweed groups had a higher abundance of beneficial bacteria in colon contents, such as Prevotella, Oscillospira and Catenisphaera. Furthermore, the addition of alginate lyase led to a lower pH in the colon (P < 0.001) and caecum (P < 0.001) of piglets, which is possibly a result of released fermentable laminarin, and is consistent with the higher proportion of butyric acid found in these intestinal compartments. L. digitata is a putative supplement to enhance piglet gut health due to its prebiotic polysaccharides. Alginate lyase supplementation further improves nutrient digestibility and prebiotic potential. These results suggest the potential use of L. digitata and these enzymatic supplements in commercial piglet-feeding practices.


Asunto(s)
Alimentación Animal , Dieta , Suplementos Dietéticos , Digestión , Glicósido Hidrolasas , Laminaria , Polisacárido Liasas , Animales , Laminaria/química , Polisacárido Liasas/metabolismo , Alimentación Animal/análisis , Dieta/veterinaria , Digestión/efectos de los fármacos , Glicósido Hidrolasas/metabolismo , Suplementos Dietéticos/análisis , Porcinos , Prebióticos , Nutrientes/metabolismo , Fenómenos Fisiológicos Nutricionales de los Animales , Destete , Microbioma Gastrointestinal/efectos de los fármacos , Masculino , Algas Comestibles
3.
Braz J Biol ; 84: e281066, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38922195

RESUMEN

The identification of meliponicultural flora is fundamental for the preservation of bees, as well as enabling the development of pollinator management and reforestation programs. In this context, this study aimed to investigate the types of pollen found in the honey and pollen pots of the Melipona fasciculata bee in Arari, State of Maranhão, between August 2022 and July 2023. 40 types of pollen were identified, distributed among 18 botanical families, with Fabaceae standing out (46.15% in pollen pots and 37.86% in honey pots), Myrtaceae (11.53% in pollen and 13.51% in honey) and Rubiaceae (7.69% in pollen and 5.40% in honey). Sapindaceae, in the honey pots, accounted for 5.40%. The other families showed lower percentages, 3.84% in the pollen pots and 2.70% in the honey pots. In terms of similarity, two distinct groups were observed in both the pollen and honey pots. In the pollen pots, group A (May-June ~ 97%) and group B (Feb-Mar ~ 99%) stood out, while in the honey pots, group A (Mar-Apr ~ 98%) and group B (Jun-Jul-Sept ~ 98%) showed the highest percentages. These findings highlight the wide range of resources used by the M. fasciculata species, as well asits preference for Fabaceae and Myrtaceae, due to the diversity and availability of trophic resources. An understanding of the meliponicultural flora is essential to support effective conservation strategies, which aim not only to guarantee the survival of the bees, but also to ensure the continued production of honey, a resource of great importance to local communities.


Asunto(s)
Miel , Polen , Polen/clasificación , Miel/análisis , Abejas/clasificación , Abejas/fisiología , Animales , Brasil , Estaciones del Año , Polinización
4.
Ann R Coll Surg Engl ; 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38787286

RESUMEN

INTRODUCTION: Experience accumulated over the last decades suggests nonoperative management (NOM) of civilian gunshot liver injuries can be safely applied in selected cases. This study aims to compare the outcomes of selective NOM versus operative management (OM) of patients sustaining gunshot wounds (GSW) to the liver. METHODS: A registry-based retrospective cohort analysis was performed for the period of 2008 to 2016 in a Brazilian trauma referral. Patients aged 16-80 years sustaining civilian GSW to right-sided abdominal quadrants and liver injury were included. Baseline data, vital signs, grade of liver injury, associated injuries, injury severity scores, blood transfusion requirements, liver- and non-liver-related complications, length-of-stay (LOS), and mortality were retrieved from individual registries. RESULTS: A total of 54 patients were eligible for analysis, of which 37 underwent NOM and 17 underwent OM. The median age was 25 years and all were male. No statistically significant differences were observed between groups regarding patients' demographics, injury scores, grade of liver injury and associated lesions. NOM patients tended to sustain higher-grade injuries (86.5% vs 64.7%; p = 0.08), and failure of conservative management was recorded in two (5.4%) cases. The rate of complications was 48% with no between-group statistically significant difference. Blood transfusion requirements were significantly higher in the OM group (58.8% vs 21.6%; p = 0.012). The median LOS was seven days. No deaths were recorded. CONCLUSION: Patients with liver GSW who are haemodynamically stable and without peritonitis are candidates for NOM. In this study, NOM was safe and effective even in high-grade injuries.

5.
Sci Rep ; 14(1): 7479, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38553528

RESUMEN

Maneuvering a spacecraft in the cislunar space is a complex problem, since it is highly perturbed by the gravitational influence of both the Earth and the Moon, and possibly also the Sun. Trajectories minimizing the needed fuel are generally preferred in order to decrease the mass of the payload. A classical method to constrain maneuvers is mathematically modeling them using the Two Point Boundary Value Problem (TPBVP), defining spacecraft positions at the start and end of the trajectory. Solutions to this problem can then be obtained with optimization techniques like the nonlinear least squares conjugated with the Theory of Functional Connections (TFC) to embed the constraints, which recently became an effective method for deducing orbit transfers. In this paper, we propose a tangential velocity (TV) type of constraints to design orbital maneuvers. We show that the technique presented in this paper can be used to transfer a spacecraft (e.g. from the Earth to the Moon) and perform gravity assist maneuvers (e.g. a swing-by with the Moon). In comparison with the TPBVP, solving the TV constraints via TFC offers several advantages, leading to a significant reduction in computational time. Hence, it proves to be an efficient technique to design these maneuvers.

8.
Phys Rev E ; 109(1-1): 014230, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38366434

RESUMEN

Recent evidence shows that heteroclinic bifurcations in magnetic islands may be caused by the amplitude variation of resonant magnetic perturbations in tokamaks. To investigate the onset of these bifurcations, we consider a large aspect ratio tokamak with an ergodic limiter composed of two pairs of rings that create external primary perturbations with two sets of wave numbers. An individual pair produces hyperbolic and elliptic periodic points, and its associated islands, that are consistent with the Poincaré-Birkhoff fixed-point theorem. However, for two pairs producing external perturbations resonant on the same rational surface, we show that different configurations of isochronous island chains may appear on phase space according to the amplitude of the electric currents in each pair of the ergodic limiter. When one of the electric currents increases, isochronous bifurcations take place and new islands are created with the same winding number as the preceding islands. We present examples of bifurcation sequences displaying (a) direct transitions from the island chain configuration generated by one of the pairs to the configuration produced by the other pair, and (b) transitions with intermediate configurations produced by the limiter pairs coupling. Furthermore, we identify shearless bifurcations inside some isochronous islands, originating nonmonotonic local winding number profiles with associated shearless invariant curves.

9.
Radiother Oncol ; 190: 109953, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37839557

RESUMEN

BACKGROUND AND PURPOSE: The FLASH effect has been validated in different preclinical experiments with electrons (eFLASH) and protons (pFLASH) operating at an average dose rate above 40 Gy/s. However, no systematic intercomparison of the FLASH effect produced by eFLASHvs. pFLASH has yet been performed and constitutes the aim of the present study. MATERIALS AND METHODS: The electron eRT6/Oriatron/CHUV/5.5 MeV and proton Gantry1/PSI/170 MeV were used to deliver conventional (0.1 Gy/s eCONV and pCONV) and FLASH (≥110 Gy/s eFLASH and pFLASH) dose rates. Protons were delivered in transmission. Dosimetric and biologic intercomparisons were performed using previously validated dosimetric approaches and experimental murine models. RESULTS: The difference between the average absorbed dose measured at Gantry 1 with PSI reference dosimeters and with CHUV/IRA dosimeters was -1.9 % (0.1 Gy/s) and + 2.5 % (110 Gy/s). The neurocognitive capacity of eFLASH and pFLASH irradiated mice was indistinguishable from the control, while both eCONV and pCONV irradiated cohorts showed cognitive decrements. Complete tumor response was obtained after an ablative dose of 20 Gy delivered with the two beams at CONV and FLASH dose rates. Tumor rejection upon rechallenge indicates that anti-tumor immunity was activated independently of the beam-type and the dose-rate. CONCLUSION: Despite major differences in the temporal microstructure of proton and electron beams, this study shows that dosimetric standards can be established. Normal brain protection and tumor control were produced by the two beams. More specifically, normal brain protection was achieved when a single dose of 10 Gy was delivered in 90 ms or less, suggesting that the most important physical parameter driving the FLASH sparing effect might be the mean dose rate. In addition, a systemic anti-tumor immunological memory response was observed in mice exposed to high ablative dose of electron and proton delivered at CONV and FLASH dose rate.


Asunto(s)
Productos Biológicos , Neoplasias , Terapia de Protones , Humanos , Animales , Ratones , Protones , Electrones , Dosificación Radioterapéutica , Radiometría
10.
Eur J Prosthodont Restor Dent ; 32(1): 56-64, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-37721553

RESUMEN

INTRODUCTION: The association of the periodontium with the fixed prosthesis is the basis of prosthetic rehabilitation. This prospective case series aimed to evaluate periodontal health through the relation between periodontal/peri-implant disease progression and the use of fixed partial dentures (FPDs). METHODS: Probing depth (PD), clinical attachment level (CAL), gingival index (GI), and plaque index (PI) on either teeth or implants were evaluated at up to 25-year follow-up and compared with the baseline. Statistical analysis was performed using the Kaplan-Meier test (p⟨0.05). RESULTS: The prospective evaluation showed that the patients maintained adequate periodontal health. Failure (severe periodontal stages) occurred in 12.5% of patients. The survival rate for 107 teeth/implants was 80.48%. The comparisons for clinical parameters revealed no statistically significant difference (p⟩ 0.05). At T1, the measurements for anterior and posterior regions, respectively, were PD =2.7mm and 3.1mm; CAL= 3.3mm and 3.6mm; GI=0.5 (both regions); and PI=0.79 and 0.62. Periodontal/peri-implant disease progression did not relate to the use of prostheses. CONCLUSIONS: Patients with more frequent follow-up appointments and lower GI and PI showed periodontal health for longer periods. Patients with different oral hygiene levels present different periodontal disease progression. Periodic hygiene control and motivation are vital factors for extensive oral rehabilitation success.


Asunto(s)
Implantes Dentales , Periimplantitis , Enfermedades Periodontales , Humanos , Implantes Dentales/efectos adversos , Enfermedades Periodontales/inducido químicamente , Dentadura Parcial Fija , Estudios de Seguimiento
11.
Braz. j. biol ; 842024.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469253

RESUMEN

Abstract The American Barn Owl (Tyto furcata) lives in urban, periurban and wild environments and feeds mainly on small rodents, meaning it has great importance in the biological control of pests. The aim of this work was to describe the reproductive, parental and eating habits of a pair of American barn owls naturally living outside a residence in the urban area of the municipality of Campos dos Goytacazes, Rio de Janeiro state, Brazil. A wood box was installed on an outside wall of the home, monitored by a video camera. A spreadsheet was created to keep track of the observations recorded. The female laid four eggs, and after an incubation period of 30-32 days all the eggs hatched, but only two chicks survived after cannibalism among the chicks. Initially, the male provided the food to the chicks and the female remained in the nest caring for the brood. After approximately a month, the female also began to leave the nest and return with prey, which was offered to the chicks, with the male also continuing this behavior. The chicks left the nest in September, 2017. The data obtained show the existence of cooperation and division of tasks between male and female owls during the reproductive period.


Resumo A coruja-das-torres americana (Tyto furcata) vive em ambientes urbanos e se alimenta principalmente de pequenos roedores, sendo de grande importância no controle biológico de pragas. O objetivo deste trabalho foi descrever os hábitos alimentares, parentais e reprodutivos de um casal de corujas-das-torres americanas, naturalmente vivendo fora de uma residência na zona urbana do município de Campos dos Goytacazes, estado do Rio de Janeiro, Brasil. Uma caixa de madeira foi instalada em uma parede externa da casa, monitorada por uma câmera de vídeo. Uma planilha foi criada para manter o controle das observações registradas. A fêmea pôs quatro ovos, e após período de incubação de 30-32 dias todos os ovos eclodiram, mas apenas dois filhotes sobreviveram após o canibalismo entre os filhotes. Inicialmente, o macho fornecia a comida aos filhotes e a fêmea permanecia no ninho cuidando da ninhada. Depois de cerca de um mês, a fêmea também começou a sair do ninho e voltar com a presa, que era oferecida aos filhotes, com o macho também continuando com esse comportamento. Os filhotes deixaram o ninho em setembro de 2017. Os dados obtidos mostram a existência de cooperação e divisão de tarefas entre corujas machos e fêmeas durante o período reprodutivo.

12.
Braz. j. biol ; 84: e249169, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1345546

RESUMEN

Abstract The American Barn Owl (Tyto furcata) lives in urban, periurban and wild environments and feeds mainly on small rodents, meaning it has great importance in the biological control of pests. The aim of this work was to describe the reproductive, parental and eating habits of a pair of American barn owls naturally living outside a residence in the urban area of the municipality of Campos dos Goytacazes, Rio de Janeiro state, Brazil. A wood box was installed on an outside wall of the home, monitored by a video camera. A spreadsheet was created to keep track of the observations recorded. The female laid four eggs, and after an incubation period of 30-32 days all the eggs hatched, but only two chicks survived after cannibalism among the chicks. Initially, the male provided the food to the chicks and the female remained in the nest caring for the brood. After approximately a month, the female also began to leave the nest and return with prey, which was offered to the chicks, with the male also continuing this behavior. The chicks left the nest in September, 2017. The data obtained show the existence of cooperation and division of tasks between male and female owls during the reproductive period.


Resumo A coruja-das-torres americana (Tyto furcata) vive em ambientes urbanos e se alimenta principalmente de pequenos roedores, sendo de grande importância no controle biológico de pragas. O objetivo deste trabalho foi descrever os hábitos alimentares, parentais e reprodutivos de um casal de corujas-das-torres americanas, naturalmente vivendo fora de uma residência na zona urbana do município de Campos dos Goytacazes, estado do Rio de Janeiro, Brasil. Uma caixa de madeira foi instalada em uma parede externa da casa, monitorada por uma câmera de vídeo. Uma planilha foi criada para manter o controle das observações registradas. A fêmea pôs quatro ovos, e após período de incubação de 30-32 dias todos os ovos eclodiram, mas apenas dois filhotes sobreviveram após o canibalismo entre os filhotes. Inicialmente, o macho fornecia a comida aos filhotes e a fêmea permanecia no ninho cuidando da ninhada. Depois de cerca de um mês, a fêmea também começou a sair do ninho e voltar com a presa, que era oferecida aos filhotes, com o macho também continuando com esse comportamento. Os filhotes deixaram o ninho em setembro de 2017. Os dados obtidos mostram a existência de cooperação e divisão de tarefas entre corujas machos e fêmeas durante o período reprodutivo.


Asunto(s)
Animales , Masculino , Femenino , Estrigiformes , Reproducción , Brasil , Conducta Alimentaria
13.
J Prev Alzheimers Dis ; 10(4): 669-674, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37874087

RESUMEN

BACKGROUND: Alzheimer's disease (AD) is a neurodegenerative disease with complex disease etiology and pathological processes. These include formation of plaques and tangles, aberrant lipid processing, neuroinflammation, cerebrovascular dysregulation, ion channel and mitochondrial dysfunction, and oxidative stress. Disease-modifying therapies focusing on all these different facets are needed. TW001 is an oral formulation with the radical scavenger edaravone as its active ingredient, targeting oxidative stress. OBJECTIVES: This manuscript describes the trial design for Phase IIA Alzheimer Study Using oRal Edaravone (ASURE). METHODS: ASURE is a randomized, placebo-controlled, proof-of-concept study aiming to evaluate safety and target engagement following administration of TW001 in early AD patients. Patients should have a biomarker confirmed diagnosis to be included in the trial and will be treated for 90 days. The primary endpoints include safety and effect of TW001 on oxidative stress biomarkers. Exploratory endpoints focus on a panel of AD(-related) fluid-based biomarkers and EEG. In addition, a recently developed cognitive functional composite (CFC) score will measure early signs of cognitive and functional effects of TW001. RESULTS: This article outlines the design of the clinical study, no results are included. CONCLUSIONS: The ASURE trial design is discussed, with a particular focus on fluid biomarkers, EEG, and CFC as endpoints. By testing multiple measures related to pathology, pharmacodynamics, EEG as proxy for cognition, and cognitive functional scores, it is expected that small changes will be detectable in trials of shorter duration. Moreover, the wide range of endpoints allows to make well-informed decisions for designing pivotal studies later.


Asunto(s)
Enfermedad de Alzheimer , Enfermedades Neurodegenerativas , Humanos , Enfermedad de Alzheimer/psicología , Edaravona/uso terapéutico , Resultado del Tratamiento , Biomarcadores , Ensayos Clínicos Controlados Aleatorios como Asunto
14.
Braz J Med Biol Res ; 56: e12894, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37851790

RESUMEN

Rapid, effective, and specific identification of clinical and environmental bacterial pathogens is of major importance for their control. Traditionally, bacteria have been identified by phenotypic methods based on morphological, biochemical, and metabolic properties. While these methods are very useful in clinical practice, they have limitations including a poor ability to differentiate within and between species and time-consuming workflows. Newly developed molecular methods can greatly improve the accuracy of taxonomic characterization, identifying specific strains of medical or environmental importance. However, due to high costs and the need for trained professionals, these methods are not yet routine in diagnostic laboratories. Thus, disseminating knowledge on advances in molecular identification techniques is pivotal to make these methodologies accessible. The objective of this work was to review and discuss current molecular techniques for bacteria identification aiming to track and monitor microbial agents in clinical and environmental samples.


Asunto(s)
Bacterias , Laboratorios , Bacterias/genética
16.
Nat Prod Res ; : 1-6, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37367484

RESUMEN

In the present study, we have evaluated the cytotoxic activity of 282 extracts from 72 native plant species of the Brazilian Atlantic Forest biome. As a result, Casearia arborea and Sorocea hilarii leaves extracts showed cytotoxic activity against three tumour cell lines tested (B16F10, SW480 and Jurkat). After bioassay-guided fractionation, the bioactive fractions were submitted to the dereplication study via High-performance Liquid Chromatography, connected to High-resolution Mass Spectrometry (HPLC-ESI-QTOF/MS) analysis, combined with a Global Natural Products Social Molecular Networking (GNPS) tool. A combination of bioactivity-guided and dereplication approaches resulted in the putative annotation of 27 clerodane diterpenes and 9 flavonoids as main compounds present in the cytotoxic fractions of C. arborea. Regarding the active fraction of S. hilarii, 10 megastigmans, 17 spirostane steroids derivatives and 2 lignans were putatively identified. In conclusion, Casearia arborea and Sorocea hilarii are potential sources of antitumor compounds.

17.
Braz J Biol ; 83: e269946, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37283335

RESUMEN

The isolation of multidrug-resistant Klebsiella pneumoniae in hospitals is a major public health threat, increasing patient hospitalization costs, morbidity and mortality. Therefore, this work investigated the resistance mechanisms that produced different carbapenems susceptibility profiles in two isogenic strains of K. pneumoniae isolated from the same patient in a public hospital in Recife, Pernambuco. The genes that encode the main porins in K. pneumoniae, ompK35 and ompK36, and several beta-lactamase genes were analyzed. The expression of these genes was evaluated by quantitative real time PCR (polymerase chain reaction) with reverse transcriptase (RT-qPCR). SDS-PAGE (sodium dodecyl sulphate-polyacrylamide gel electrophoresis) was performed to analyze the outer membrane proteins. The analysis of the ompK36 genetic environment disclosed an IS903 insertion sequence disrupting this gene in the ertapenem resistant isolate (KPN133). The blaKPC-2 gene showed down-regulated expression in both isolates. Our findings show that changes in porins, especially OmpK36, are more determinant to carbapenems susceptibility profile of bacterial isolates than variations in blaKPC gene expression.


Asunto(s)
Carbapenémicos , Infecciones por Klebsiella , Humanos , Carbapenémicos/farmacología , Carbapenémicos/metabolismo , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/metabolismo , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Infecciones por Klebsiella/microbiología , Porinas/genética , Porinas/metabolismo , Pruebas de Sensibilidad Microbiana
18.
Environ Monit Assess ; 195(6): 659, 2023 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-37166583

RESUMEN

Rare earth elements (REE) have unique chemical properties, which allow their use as geochemical tracers. In this context, the present study aims to assess the role of Funil Reservoir on REE biogeochemical behavior. We collected water samples upstream of the reservoir (P-01) in the city of Queluz, inside the reservoir (P-02), and downstream of Funil Reservoir (P-03) in the city of Itatiaia, RJ. In the field, physicochemical parameters were measured using a probe (pH, temperature, electrical conductivity, and dissolved oxygen). In the laboratory, water samples were filtered (0.45 µm) and properly packed until chemical analysis. Chlorophyll a concentrations were determined by a spectrophotometric method and suspended particulate matter (SPM) by a gravimetric method. Ionic concentrations were determined by ion chromatography technique and REE concentrations were determined by ICP-MS. Chlorophyll a concentrations were higher in Funil Reservoir. Ionic concentrations in Queluz (P-01) suggest anthropic contamination. The sum of REE in the dissolved fraction ranged from 2.12 to 12.22 µg L-1. A positive anomaly of La in Queluz indicates anthropic contamination. The observed patterns indicate that Funil Reservoir acts as a biogeochemical barrier, modifying the fluvial transport of REE. Nonetheless, another factor that probably influences REE behavior is the algal bloom that occurs in reservoirs during the rainy season. The seasonal behavior of algae can influence REE biogeochemistry through the incorporation and release of trace metals.


Asunto(s)
Metales de Tierras Raras , Contaminantes Químicos del Agua , Clorofila A/análisis , Brasil , Monitoreo del Ambiente , Metales de Tierras Raras/análisis , Agua/análisis , Contaminantes Químicos del Agua/análisis
19.
bioRxiv ; 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37131769

RESUMEN

Background and purpose: The FLASH effect has been validated in different preclinical experiments with electrons (eFLASH) and protons (pFLASH) operating at a mean dose rate above 40 Gy/s. However, no systematic intercomparison of the FLASH effect produced by e vs. pFLASH has yet been performed and constitutes the aim of the present study. Materials and methods: The electron eRT6/Oriatron/CHUV/5.5 MeV and proton Gantry1/PSI/170 MeV were used to deliver conventional (0.1 Gy/s eCONV and pCONV) and FLASH (≥100 Gy/s eFLASH and pFLASH) irradiation. Protons were delivered in transmission. Dosimetric and biologic intercomparisons were performed with previously validated models. Results: Doses measured at Gantry1 were in agreement (± 2.5%) with reference dosimeters calibrated at CHUV/IRA. The neurocognitive capacity of e and pFLASH irradiated mice was indistinguishable from the control while both e and pCONV irradiated cohorts showed cognitive decrements. Complete tumor response was obtained with the two beams and was similar between e and pFLASH vs. e and pCONV. Tumor rejection was similar indicating that T-cell memory response is beam-type and dose-rate independent. Conclusion: Despite major differences in the temporal microstructure, this study shows that dosimetric standards can be established. The sparing of brain function and tumor control produced by the two beams were similar, suggesting that the most important physical parameter driving the FLASH effect is the overall time of exposure which should be in the range of hundreds of milliseconds for WBI in mice. In addition, we observed that immunological memory response is similar between electron and proton beams and is independent off the dose rate.

20.
Public Health ; 219: 61-66, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37119795

RESUMEN

OBJECTIVES: Tobacco companies have introduced heated tobacco product (HTP) in many countries and marketed it on the grounds that it is a less harmful alternative to health. However, tobacco companies have been widely criticized for taking advantage of a loophole that allows electronic devices to circumvent regulations limiting tobacco advertising. This work aims to determine whether HTPs respected the rules that regulate tobacco advertising when it was introduced in Spain. STUDY DESIGN: This is an observational epidemiological study. METHODS: Using monthly time series data from September 2016 to June 2020, we analyzed whether the adoption of HTPs has followed the same behavior patterns as other brands that were introduced under the same conditions of use. The Bass model is used to analyze the diffusion of HTPs, and 30 other traditional cigarette brands introduced under the same conditions as this HTPs. RESULTS: The adoption of HTPs in Spain has been like that of brands of slim cigarettes that are mistakenly considered to be healthier than traditional cigarettes. The results indicate that the use of HTPs has spread in the same way as additive-free and ultra-slim cigarette brands. CONCLUSIONS: Policymakers should keep in mind that laws should restrict any marketing of tobacco products that promotes positive connotations between tobacco use and being healthy. If manufacturers are allowed to classify a category and/or brand of tobacco products as less harmful to health, the imitation effect is very high, leading to the proliferation of smoking.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Productos de Tabaco , Humanos , España/epidemiología , Fumar , Uso de Tabaco
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