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1.
Toxicon ; 255: 108263, 2025 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-39864753

RESUMO

Tityus serrulatus accident promote vast symptomatology related to toxins of the venom, which leads to a massive release of neurotransmitters, notably dopamine, affecting behavior and neurochemistry. The recommended treatment for envenomation is the antiscorpionic serum (SAEsc) administration. Related to this complexity of the Tityus serrulatus envenomation, this study aimed to assess organism responses to the venom, its impact on behavior, oxidative stress, neurochemistry, and genetic impacts, as well as the efficacy of SAEsc, especially concerning dopamine levels and genetic interactions. Swiss mice were divided into groups and administered different venom concentrations intracerebroventricularly to assess behavioral impacts and brain oxidative stress. Oxidative stress was evaluated through reactive oxygen species (ROS) analysis and antioxidant assays, including dichloro-dihydro-fluorescein diacetate (DCF), thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), and glutathione (GSH) measurements. Swiss mice were divided into four groups to evaluate genomic modulation, micronucleus enhancement, and dopamine levels. Additionally, SAEsc's neutralizing effect on dopamine was also investigated. Results showed that venom doses (100-300 ng/µL) increased lipid peroxidation in the brain, with SAEsc maintaining dopamine balance and neutralizing venom up to 24 h post-envenomation. After 24 h, cellular repair became less efficient, leading to mutagenic damage in both treated and untreated animals. The results highlight the importance of considering genomic and neurotransmitter function modulation in the treatment of Tityus serrulatus envenomation.

2.
Neurotox Res ; 43(1): 5, 2025 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-39833594

RESUMO

Given ketamine's conflicting impacts on the central nervous system, investigating its effects within an inflammatory context becomes crucial. This study aimed to assess the impact of varying ketamine doses on neurotrophin and inflammatory cytokine levels within the brains of rats submitted to the sepsis model. Wistar rats were submitted to the cecal ligation and puncture (CLP) model of sepsis. Intraperitoneal ketamine injections (5, 15, or 25 mg/kg) or saline were administered daily for seven days, thirty days post-CLP. Rats were euthanized thirty minutes following the last injection for analysis of IL-1ß, IL-6, IL-10, TNF-α, BDNF, NGF, NT-3, and GDNF levels in the frontal cortex, hippocampus, and striatum. CLP-induced elevated IL-1𝛽, IL-6, IL-10, and TNF-α levels in the frontal cortex and hippocampus of rats, with reduced BDNF levels across all structures examined. Furthermore, reduced NGF and GDNF levels were observed solely in the hippocampus. Ketamine at 5 mg/kg normalized CLP-induced alterations and, in Sham animals, increased BDNF and NGF levels in the frontal cortex and/or hippocampus. At 15 mg/kg, ketamine elevated BDNF and NGF levels in Sham animals, while at 25 mg/kg, it exacerbated the inflammatory response initiated by CLP. These findings suggest variable effects of ketamine within a context of systemic inflammation, emphasizing the importance of considering individual inflammatory backgrounds when utilizing ketamine.


Assuntos
Ceco , Modelos Animais de Doenças , Ketamina , Fatores de Crescimento Neural , Ratos Wistar , Sepse , Animais , Ketamina/farmacologia , Ketamina/administração & dosagem , Sepse/metabolismo , Sepse/induzido quimicamente , Sepse/tratamento farmacológico , Masculino , Fatores de Crescimento Neural/metabolismo , Ceco/cirurgia , Ligadura , Ratos , Citocinas/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Punções , Fator Neurotrófico Derivado do Encéfalo/metabolismo
3.
Phys Chem Chem Phys ; 27(4): 2011-2022, 2025 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-39749576

RESUMO

Illite mineral is present in shale rocks, and its wettability behavior is significant for the oil and gas industry. In this work, the pH effects on the affinity between the (001) and (010) crystallographic planes of illite K2(Si7Al)(Al3Mg)O20(OH)4 and direct and inverse emulsions were studied using molecular dynamics simulations. To develop the simulations, an atomistic model of illite was constructed following Löwenstein's rule. The oily phase was modeled using heptane, toluene, and mixtures of heptane/heptanoic acid, heptane/heptanoate, heptane/hexylamine and heptane/hexylammonium. For the heptane/heptanoate and heptane/hexylammonium mixtures, Na+ and Cl- ions were used to neutralize the excess electrical charge of the droplets, respectively. The affinity of the mineral surface to the oil models was estimated by the contact angle for systems where it was possible. However, for systems where the droplets did not adhere to the mineral, a methodology based on the height of the droplet on the surface was proposed. The results showed that, in general, for the inverse emulsions, water exhibited a high affinity for both illite surfaces, with its contact angle remaining below 45° regardless of pH. However, the heptane/heptanoic acid inverse emulsions on the edge surface were an exception to this behavior. Specifically, the contact angles calculated for the water droplets revealed mixed wettability due to hydrogen bonds between the carboxylic functional groups (pH ≪ 4.4) and the surface silanols and aluminols. Oil droplets suspended in water, on the other hand, did not adhere to the illite surfaces, and contact angles were not measurable. Nevertheless, the heptane/heptanoic acid droplets (pH ≪ 4.4) showed heights of approximately 2 Å and 4 Å above the basal and edge surfaces, respectively. This behavior was attributed to the hydrogen bonds formed between the carboxylic functional groups and the water molecules located on the mineral surfaces. Finally, the heptane/heptanoate (pH ≫ 4.4) and heptane/hexylammonium (pH ≪ 10.64) droplets were localized at distances greater than 8 Å from the surface, presumably due to a charge repulsion between the mineral surface and the surface of the droplets.

4.
Ecol Appl ; : e3071, 2024 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-39639421

RESUMO

Identifying how species richness or diversity changes with different proportions of natural and anthropized environments in the landscape is important for landscape management for conservation. Here, we propose a new method to assess biodiversity changes in landscapes with varying proportions of habitat types. The algorithm is based on the resampling of individuals recorded in different habitats considering both the proportion occupied by each habitat in the landscape and the number of individuals recorded in each habitat. The diversity is assessed based on the sampled individuals. If a functional/phylogenetic tree or distance matrix is provided, the function returns the functional or phylogenetic richness values. This procedure is replicated a number of times with different proportions of each of the habitats in the landscape. Our method copes with two or more habitat types in the landscape and works with taxonomic, functional, and phylogenetic diversities. We tested our method using 10 different simulated scenarios and one empirical dataset with bats (Chiroptera) to assess whether they behaved as expected. Our method performed as expected in all scenarios and in the empirical dataset (considering also the functional and phylogenetic diversities in this latter case). The possibility of working with more than two habitat types and with different dimensions of diversity (i.e., functional and phylogenetic diversity) is a major advantage of the new method. We show that this is a valuable tool to assess biodiversity changes in the context of landscape planning, helping to promote more sustainable landscapes often composed of multiple habitat types with mixed biodiversity composition.

5.
Zootaxa ; 5481(2): 151-202, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39646046

RESUMO

Based on an exhaustive review of the bibliography, and consultation of entomological collections around the world, we present an illustrated catalog with 16 Castniidae taxa present in Costa Rica. Corybantes veraguana veraguana (Westwood, 1877) is recorded for the first time in the country and new records are reported for rare and little-known species such as Athis analibiae (Espinoza-Sanabria & González, 2005), Athis delecta (Schaus, 1911) and Mirocastnia pyrrhopygoides smalli Miller, 1980. A taxonomic catalog of each taxon is included, as well as general information on geographic distribution, biogeography, ecology, seasonality, flight habits, material examined, and illustrations of males and females for all those taxa known from more than one specimen from Costa Rica.


Assuntos
Distribuição Animal , Mariposas , Animais , Costa Rica , Feminino , Masculino , Mariposas/anatomia & histologia , Mariposas/classificação , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Tamanho Corporal , Ecossistema , Tamanho do Órgão
6.
Biomater Sci ; 2024 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-39686765

RESUMO

Repair of damaged or faulty complex modular organs such as the urinary bladder is a current clinical challenge. The design of constructs for reconstructive urological surgery can draw advantage from the bioactivity of natural extracellular matrix (ECM) bioscaffolds, as well as the activity provided by cells seeded into constructs. Considering these benefits, this work compares the performance of pericardial ECM bioscaffolds and constructs seeded with gel-supported urothelial cells in the repair of urinary bladder defects in rabbits. The bioscaffolds considered in this study are of porcine (pM) and bovine (bM) origin and exhibited a residual composition that confers bioactivity in mesh presentation. Coating an ECM gel on the bioscaffolds promoted the adhesion and viability of urothelial cells. Repairing a full-thickness urinary bladder defect in a rabbit model with the bioscaffolds and constructs resulted in the integration with the host bladder; meanwhile, bladder volumetric capacity was promoted using bM and constructs. Although no contribution of gel/cell seeding to the failure of mechanical properties of the urinary neobladder was observed, this seeding technique is suitable for integration with different strategies to engineer constructs for urinary bladder reconstructive surgery.

7.
Nutrients ; 16(18)2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39339721

RESUMO

Our study aimed to validate existing equations and develop the new NRGCO equation to estimate resting energy expenditure (REE) in the Colombian population with moderate-to-high physical activity levels. Upon satisfying the inclusion criteria, a total of 86 (43F, 43M) healthy adults (mean [SD]: 27.5 [7.7] years; 67.0 [13.8] kg) were evaluated for anthropometric variables and REE by indirect calorimetry using wearable gas analyzers (COSMED K4 and K5). Significant positive correlations with REE were found for body mass (r = 0.65), body mass-to-waist (r = 0.58), arm flexed and tensed girth (r = 0.66), corrected thigh girth (r = 0.56), corrected calf girth (r = 0.61), and sum of breadths (∑3D, r = 0.59). As a novelty, this is the first time a significant correlation between REE and the sum of corrected girths (∑3CG, r = 0.63) is reported. Although existing equations such as Harris-Benedict (r = 0.63), Mifflin-St. Jeor (r = 0.67), and WHO (r = 0.64) showed moderate-to-high correlations with REE, the Bland-Altman analysis revealed significant bias (p < 0.05), indicating that these equations may not be valid for the Colombian population. Thus, participants were randomly distributed into either the equation development group (EDG, n = 71) or the validation group (VG, n = 15). A new model was created using body mass, sum of skinfolds (∑8S), corrected thigh, corrected calf, and age as predictors (r = 0.755, R2 = 0.570, RMSE = 268.41 kcal). The new NRGCO equation to estimate REE (kcal) is: 386.256 + (24.309 × BM) - (2.402 × ∑8S) - (21.346 × Corrected Thigh) + (38.629 × Corrected Calf) - (7.417 × Age). Additionally, a simpler model was identified through Bayesian analysis, including only body mass and ∑8S (r = 0.724, R2 = 0.525, RMSE = 282.16 kcal). Although external validation is needed, our validation resulted in a moderate correlation and concordance (bias = 91.5 kcal) between measured and estimated REE values using the new NRGCO equation.


Assuntos
Calorimetria Indireta , Humanos , Masculino , Adulto , Feminino , Colômbia , Adulto Jovem , Dobras Cutâneas , Metabolismo Energético/fisiologia , Descanso/fisiologia , Metabolismo Basal/fisiologia , Índice de Massa Corporal , Antropometria , Exercício Físico/fisiologia , Reprodutibilidade dos Testes
8.
Arq Bras Cardiol ; 121(8): e20230707, 2024.
Artigo em Português, Inglês | MEDLINE | ID: mdl-39258653

RESUMO

BACKGROUND: Chronic Chagas cardiomyopathy (CCC) is caused by an inflammatory process induced by Trypanosoma cruzi, which leads to myocarditis with reactive and reparative fibrosis. CCC progresses with myocardial perfusion abnormalities and histopathological events that affect cardiorespiratory fitness (CRF). OBJECTIVES: We evaluated the effects of aerobic physical training (APT) on myocardial perfusion and on morphological and functional impairments related with inflammation and fibrosis in Syrian hamsters with CCC. As a secondary objective, we analyzed the cross-sectional areas of the skeletal muscle. METHODS: Hamsters with CCC and their respective controls were divided into four groups: CCC sedentary, CCC-APT, sedentary control and APT control. Seven months after infection, the animals underwent echocardiography, myocardial perfusion scintigraphy and cardiopulmonary exercise testing. Moderate-intensity APT was performed for fifty minutes, five times a week, for eight weeks. Subsequently, the animals were reassessed. Histopathological analysis was conducted after the above-mentioned procedures. The level of significance was set at 5% in all analyses (p<0.05). RESULTS: CCC sedentary animals presented worse myocardial perfusion defects (MPD) over time, reduced left ventricle ejection fraction (LVEF) and showed more inflammation and fibrosis when compared to other groups (mixed ANOVA analysis). Conversely, APT was able to mitigate the progression of MPD, ameliorate inflammation and fibrosis and improve CRF efficiency in CCC-APT animals. CONCLUSIONS: Our study demonstrated that APT ameliorated cardiac dysfunction, MPD, and reduced inflammation and fibrosis in CCC hamster models. Additionally, CCC-SED animals presented skeletal muscle atrophy while CCC-APT animals showed preserved skeletal muscle CSA. Understanding APT's effects on CCC's pathophysiological dimensions is crucial for future research and therapeutic interventions.


FUNDAMENTO: A Cardiomiopatia Chagásica Crônica (CCC) é causada por um processo inflamatório induzido pelo Trypanosoma cruzi, que leva à miocardite com fibrose reativa e reparativa. A CCC progride com alterações de perfusão miocárdica e eventos histopatológicos que afetam a Aptidão Cardiorrespiratória (ACR). OBJETIVOS: Avaliamos os efeitos do Treinamento Físico Aeróbico (TFA) na perfusão miocárdica e nos comprometimentos morfológicos e funcionais relacionados à inflamação e fibrose em hamsters sírios com CCC. Como objetivo secundário, analisamos as áreas de secção transversa do músculo esquelético. MÉTODOS: Hamsters com CCC e seus respectivos controles foram divididos em quatro grupos: CCC sedentário, CCC-TFA, controle sedentário e controle TFA. Sete meses após a infecção, os animais foram submetidos à ecocardiografia, à cintilografia de perfusão miocárdica e ao teste de esforço cardiopulmonar. TFA de intensidade moderada foi realizado durante cinquenta minutos, cinco vezes por semana, por oito semanas. Posteriormente, os animais foram reavaliados. A análise histopatológica foi realizada após os procedimentos acima mencionados. O nível de significância foi estabelecido em 5% em todas as análises (p<0,05). RESULTADOS: Animais com CCC sedentários apresentaram piores Defeitos de Perfusão Miocárdica (DPM) ao longo do tempo, Fração de Ejeção do Ventrículo Esquerdo (FEVE) reduzida, e apresentaram mais inflamação e fibrose quando comparados aos demais grupos (análise ANOVA mista). Por outro lado, o TFA foi capaz de mitigar a progressão do DPM, atenuar a inflamação e a fibrose e melhorar a eficiência da ACR em animais CCC-TFA. CONCLUSÃO: Nosso estudo demonstrou que o TFA melhorou a disfunção cardíaca, DPM e reduziu a inflamação e a fibrose em modelos de hamster com CCC. Além disso, os animais CCC-SED apresentaram atrofia do músculo esquelético, enquanto os animais CCC-TFA apresentaram a AST do músculo esquelético preservada. Compreender os efeitos da TFA nas dimensões fisiopatológicas da CCC é crucial para futuras pesquisas e intervenções terapêuticas.


Assuntos
Cardiomiopatia Chagásica , Modelos Animais de Doenças , Fibrose , Condicionamento Físico Animal , Animais , Cardiomiopatia Chagásica/fisiopatologia , Cardiomiopatia Chagásica/terapia , Condicionamento Físico Animal/fisiologia , Doença Crônica , Masculino , Miocárdio/patologia , Ecocardiografia , Cricetinae , Inflamação , Fatores de Tempo , Mesocricetus , Músculo Esquelético/fisiopatologia , Músculo Esquelético/patologia , Teste de Esforço , Imagem de Perfusão do Miocárdio/métodos , Reprodutibilidade dos Testes , Miocardite/fisiopatologia , Miocardite/terapia
9.
Eur Arch Paediatr Dent ; 25(5): 715-720, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39266902

RESUMO

AIM: To investigate the association between presence of caries in anterior teeth and bullying victimization in schoolchildren. METHODS: A cross-sectional study was conducted in Brazil with a sample of 387 schoolchildren aged 6 to 10 years. The presence of moderate/extensive dental caries was assessed using the International System for the Evaluation and Detection of Dental Caries (ICDAS-II). The children answered the "Olweus Bullying" (QBO). Descriptive analyses were performed, and the associations between bullying victimization and independent variables collected were determined by univariate and multivariate Poisson regression. RESULTS: The prevalence of bullying victimization was 66.4%. Bullying victimization was higher among children who had moderate/extensive caries in some anterior teeth (p = 0.010). 8-year-old (p = 0.048), 9-year-old (p = 0.001), and 10-year-old (p = 0.002) children reported greater bullying victimization when compared to 6-year-olds. CONCLUSION: The presence of moderate/extensive dental caries in anterior teeth is associated with bullying victimization in schoolchildren.


Assuntos
Bullying , Cárie Dentária , Humanos , Criança , Estudos Transversais , Brasil/epidemiologia , Cárie Dentária/epidemiologia , Masculino , Feminino , Bullying/estatística & dados numéricos , Vítimas de Crime/estatística & dados numéricos , Prevalência
10.
Waste Manag Res ; : 734242X241279942, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39302029

RESUMO

The term food loss and waste (FLW) refers to discarded food during the different stages of the food chain. Food loss occurs during the initial stages of the food chain, and food waste occurs during the final stages. The relation between FLW and circular economy (CE) is particularly important for countries which are beginning to implement actions or regulations on this topic. These proposals may have an impact in strategic sectors of their economy. The objective of this review document was to analyse the regulations of FLW and CE in some countries located throughout the European Union, Asia, Africa and Latin America. To fulfil this objective, FLW and CE regulations were identified and analysed in 12 countries located in the aforementioned regions. The analysis showed that France, Spain, Japan and Uruguay included objectives related to FLW in their CE legislations focusing on food waste reduction, whereas China, Chile, Argentina and Mexico did not include FLW in their CE legislations. African countries did not have CE legislations in place yet. France and Japan have had more success in the reduction of FLW. In conclusion, CE regulation should include FLW regulation to achieve more efficiency at reducing and reusing these residues.

11.
Phys Med Biol ; 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39214124

RESUMO

OBJECTIVE: Image quality in positron emission tomography (PET) is influenced by positron range. In this work, the effect of the magnetic field of a PET/MR Siemens Biograph mMR 3T on the quality of PET images was studied. APPROACH: Experimental measurements were conducted using18F and68Ga-filled phantoms to quantify image uniformity, recovery coefficients (RCs), spill-over ratios and percent contrast for spherical lesions. Tissue-equivalent phantoms (lung inhale and exhale, adipose, water, trabecular and cortical bone) were used together with a line source to quantify the impact of the magnetic field on the reconstructed PET images. A comparative analysis was made with images obtained with a PET/CT Biograph Vision 600, using the same radionuclides and phantoms. MAIN RESULTS: Higher RCs values were obtained when the image quality phantom was filled with68Ga and scanned with the PET/MR system compared to those obtained with the PET/CT scanner. Hot spheres in the lesion detectability phantom, appear contracted in the transverse direction in the PET/MR system, an effect more evident for68Ga compared to18F, but no elongation in the direction parallel to the magnetic field was observed. In the PET/CT scanner, radial profiles taken from axial slices of line sources, show longer distribution tails extending beyond 20 mm when filled with68Ga and placed inside lung-inhale tissue. In the PET/MR scanner the radial profiles of all materials collapsed into a single distribution with tails extending no more than 10 mm in the direction perpendicular to the magnetic field. SIGNIFICANCE: Positron range depends on positron energy and material density in which they traverse. The results show an evident improvement in image quality in the transaxial direction only, particularly in phantoms filled with68Ga when using a PET/MR system as opposed to images acquired in the PET/CT system due to the presence of the magnetic field.

12.
World J Diabetes ; 15(8): 1717-1725, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39192864

RESUMO

BACKGROUND: Autoimmunity has emerged as a probable disease modifier in patients with clinically diagnosed type 2 diabetes mellitus (T2DM), that is, patients who have insulin resistance, obesity, and other cardiovascular risk factors, suggesting that the presence of glutamic acid decarboxylase (anti-GAD65), islet antigen 2 (anti-IA2), and zinc transporter 8 (anti-Zn8T) antibodies could have deleterious effects on beta cell function, causing failure and earlier requirement for insulin treatment. AIM: To evaluate anti-GAD65, anti-IA2 and anti-Zn8T as predictors of early insulin requirement in adolescents with a clinical diagnosis of T2DM. METHODS: This was a case-control study in patients with clinically diagnosed with T2DM (68 cases and 64 controls with and without early insulin dependence respectively), male and female, aged 12-18 years. Somatometry, blood pressure, glucose, insulin, C-peptide, glycated hemoglobin A1c, and lipid profiles were assessed. ELISA was used to measure anti-GAD65, anti-IA2, and anti-Zn8T antibodies. Descriptive statistics, Pearson's χ 2 test, Student's t test, and logistic regression was performed. P < 0.05 was considered statistically significant. RESULTS: There were 132 patients (53.8% female), with a mean age was 15.9 ± 1.3 years, and there was a disease evolution time of 4.49 ± 0.88 years. The presence of anti-GAD65, anti-IA2, and anti-Zn8T positivity was found in 29.5%, 18.2%, and 15.9%, respectively. Dividing the groups by early or no insulin dependence showed that the group with insulin had a higher frequency of antibody positivity: anti-GAD65 odds ratio (OR): 2.42 (1.112-5.303, P = 0.026); anti-IA2: OR: 1.55 (0.859-2.818, P = 0.105); and anti-Zn8T: OR: 7.32 (2.039-26.279, P = 0.002). CONCLUSION: Anti-GAD65 positivity was high in our study. Anti-GAD65 and anti-Zn8T positivity showed a significantly depleted beta cell reserve phenotype, leading to an increased risk of early insulin dependence.

13.
Arq. bras. cardiol ; Arq. bras. cardiol;121(8): e20230707, ago. 2024. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1573939

RESUMO

Resumo Fundamento: A Cardiomiopatia Chagásica Crônica (CCC) é causada por um processo inflamatório induzido pelo Trypanosoma cruzi, que leva à miocardite com fibrose reativa e reparativa. A CCC progride com alterações de perfusão miocárdica e eventos histopatológicos que afetam a Aptidão Cardiorrespiratória (ACR). Objetivos: Avaliamos os efeitos do Treinamento Físico Aeróbico (TFA) na perfusão miocárdica e nos comprometimentos morfológicos e funcionais relacionados à inflamação e fibrose em hamsters sírios com CCC. Como objetivo secundário, analisamos as áreas de secção transversa do músculo esquelético. Métodos: Hamsters com CCC e seus respectivos controles foram divididos em quatro grupos: CCC sedentário, CCC-TFA, controle sedentário e controle TFA. Sete meses após a infecção, os animais foram submetidos à ecocardiografia, à cintilografia de perfusão miocárdica e ao teste de esforço cardiopulmonar. TFA de intensidade moderada foi realizado durante cinquenta minutos, cinco vezes por semana, por oito semanas. Posteriormente, os animais foram reavaliados. A análise histopatológica foi realizada após os procedimentos acima mencionados. O nível de significância foi estabelecido em 5% em todas as análises (p<0,05). Resultados: Animais com CCC sedentários apresentaram piores Defeitos de Perfusão Miocárdica (DPM) ao longo do tempo, Fração de Ejeção do Ventrículo Esquerdo (FEVE) reduzida, e apresentaram mais inflamação e fibrose quando comparados aos demais grupos (análise ANOVA mista). Por outro lado, o TFA foi capaz de mitigar a progressão do DPM, atenuar a inflamação e a fibrose e melhorar a eficiência da ACR em animais CCC-TFA. Conclusão: Nosso estudo demonstrou que o TFA melhorou a disfunção cardíaca, DPM e reduziu a inflamação e a fibrose em modelos de hamster com CCC. Além disso, os animais CCC-SED apresentaram atrofia do músculo esquelético, enquanto os animais CCC-TFA apresentaram a AST do músculo esquelético preservada. Compreender os efeitos da TFA nas dimensões fisiopatológicas da CCC é crucial para futuras pesquisas e intervenções terapêuticas.


Abstract Background: Chronic Chagas cardiomyopathy (CCC) is caused by an inflammatory process induced by Trypanosoma cruzi, which leads to myocarditis with reactive and reparative fibrosis. CCC progresses with myocardial perfusion abnormalities and histopathological events that affect cardiorespiratory fitness (CRF). Objectives: We evaluated the effects of aerobic physical training (APT) on myocardial perfusion and on morphological and functional impairments related with inflammation and fibrosis in Syrian hamsters with CCC. As a secondary objective, we analyzed the cross-sectional areas of the skeletal muscle. Methods: Hamsters with CCC and their respective controls were divided into four groups: CCC sedentary, CCC-APT, sedentary control and APT control. Seven months after infection, the animals underwent echocardiography, myocardial perfusion scintigraphy and cardiopulmonary exercise testing. Moderate-intensity APT was performed for fifty minutes, five times a week, for eight weeks. Subsequently, the animals were reassessed. Histopathological analysis was conducted after the above-mentioned procedures. The level of significance was set at 5% in all analyses (p<0.05). Results: CCC sedentary animals presented worse myocardial perfusion defects (MPD) over time, reduced left ventricle ejection fraction (LVEF) and showed more inflammation and fibrosis when compared to other groups (mixed ANOVA analysis). Conversely, APT was able to mitigate the progression of MPD, ameliorate inflammation and fibrosis and improve CRF efficiency in CCC-APT animals. Conclusions: Our study demonstrated that APT ameliorated cardiac dysfunction, MPD, and reduced inflammation and fibrosis in CCC hamster models. Additionally, CCC-SED animals presented skeletal muscle atrophy while CCC-APT animals showed preserved skeletal muscle CSA. Understanding APT's effects on CCC's pathophysiological dimensions is crucial for future research and therapeutic interventions.

14.
Heliyon ; 10(13): e33019, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39035509

RESUMO

Microgrids (MGs) based on renewable energies have emerged as a proficient strategy for tackling power quality issues in conventional distribution networks. Nonetheless, MG systems require a suitable control scheme to supply energy optimally towards the electrical grid. This paper presents an innovative framework for designing hybrid Proportional-Resonant (PR) controllers with Linear Quadratic Regulators (LQR), PR+LQR, which merge relevant properties of PR and LQR controllers. This method simultaneously determines the MG control parameters and the current unbalanced factor generated at the distribution network. We select the traditional IEEE 13-bus test feeder network and place two MGs at strategic locations to validate our approach. Moreover, we use the Grey Wolf Optimizer (GWO) to find control parameters through a reliable fitness function that leads to high-performance microgrids. Finally, we conceive several tests to assess the efficacy of GWO for tuning the hybrid controller and compare the resulting data across distinct realistic operation conditions representing power quality events. So, we choose four case studies considering different renewable energy penetration indexes and power factors and evaluate the effects of the MGs over the distribution grid. We also compare the proposed hybrid PR+LQR controller against closely-related alternatives from the literature and validate its robustness and stability through the disk margin approach and the Nyquist criterion. Our numerical simulations prove that hybrid controllers driven by GWO are highly reliable strategies, yielding an average unbalanced current reduction of 30.03%.

15.
Molecules ; 29(14)2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39064853

RESUMO

Tetroxane derivatives are interesting drugs for antileishmaniasis and antimalaric treatments. The gas-phase thermal decomposition of 3,6,-dimethyl-1,2,4,5-tetroxane (DMT) and 3,3,6,6,-tetramethyl-1,2,4,5-tetroxane (acetone diperoxide (ACDP)) was studied at 493-543 K by direct gas chromatography by means of a flow reactor. The reaction is produced in the injector chamber at different temperatures. The resulting kinetics Arrhenius equations were calculated for both tetroxanes. Including the parent compound of the series 1,2,4,5-tetroxane (formaldehyde diperoxide (FDP)), the activation energy and frequency factors decrease linearly with the number of methyl groups. The reaction mechanisms of ACDP and 3,6,6-trimethyl-1,2,4,5-tetroxane (TMT) decomposition have been studied by means of the DFT method with the BHANDHLYP functional. Our calculations confirm that the concerted mechanism should be discarded and that only the stepwise mechanism occurs. The critical points of the singlet and triplet state potential energy surfaces (S- and T-PES) of the thermolysis reaction of both compounds have been determined. The calculated activation energies of the different steps vary linearly with the number of methyl groups of the methyl-tetroxanes series. The mechanism for the S-PES leads to a diradical O···O open structure, which leads to a C···O dissociation in the second step and the production of the first acetaldehyde/acetone molecule. This last one yields a second C···O dissociation, producing O2 and another acetone/acetaldehyde molecule. The O2 molecule is in the singlet state. A quasi-parallel mechanism for the T-PES from the open diradical to products is also found. Most of the critical points of both PES are linear with the number of methyl groups. Reaction in the triplet state is much more exothermic than the singlet state mechanism. Transitions from the singlet ground state, S0 and low-lying singlet states S1-3, to the low-lying triplet excited states, T1-4, (chemical excitation) in the family of methyl tetroxanes are also studied at the CASSCF/CASPT2 level. Two possible mechanisms are possible here: (i) from S0 to T3 by strong spin orbit coupling (SOC) and subsequent fast internal conversion to the excited T1 state and (ii) from S0 to S2 from internal conversion and subsequent S2 to T1 by SOC. From these experimental and theoretical results, the additivity effect of the methyl groups in the thermolysis reaction of the methyl tetroxane derivatives is clearly highlighted. This information will have a great impact for controlling these processes in the laboratory and chemical industries.

16.
Methods Mol Biol ; 2827: 279-290, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985277

RESUMO

This chapter presents an efficient protocol for regenerating Carica papaya plants via somatic embryogenesis from immature zygotic embryos from economically important papaya genotypes. To achieve regenerated plants from somatic embryos, in the present protocol, four induction cycles are required, followed by one multiplication cycle and one regeneration cycle. With this optimized protocol, 80% of somatic embryos can be obtained in only 3.5 months. At this stage, calli containing more than 50% globular structures can be used for transformation (via agrobacterium, biobalistics, or any other transformation method). Once transformed, calli can be transferred to the following steps (multiplication, elongation, maturation, rooting, and ex vitro acclimatization) to regenerate a transformed somatic embryo-derived full plant.


Assuntos
Carica , Genótipo , Técnicas de Embriogênese Somática de Plantas , Carica/genética , Carica/embriologia , Técnicas de Embriogênese Somática de Plantas/métodos , Transformação Genética , Plantas Geneticamente Modificadas/genética , Regeneração/genética , Sementes/genética , Sementes/crescimento & desenvolvimento
17.
Bone ; 187: 117211, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39053792

RESUMO

Osteonecrosis of the jaw (ONJ) is a relatively rare side effect after prolonged use of bisphosphonates, which are drugs used to treat bone resorption in osteoporosis and certain cancers. This study introduces a novel ONJ model in rats by combining exposure to bisphosphonates, oral surgery, and bacterial inoculation. Potential ONJ preventive effects of polyguanidine (GuaDex) or antibiotics were evaluated. The study consisted of twenty-four male Wistar rats were divided into four groups. Groups 1 to 3 were given weekly doses of i.v. Zoledronic acid (ZA), four weeks before and two weeks after an osteotomy procedure on their left mandibular first molar. Group 4 was a negative control. Streptococcus gordonii bacteria were introduced into the osteotomy pulp chamber and via the food for seven days. On day eight, the rats were given different treatments. Group 1 was given a GuaDex injection into the osteotomy socket, Group 2 was given an intramuscular (i.m.) injection of clindamycin, Group 3 (positive control) was given an i.m. injection of saline, and Group 4 was given an i.m. injection of saline. Blood samples were taken two weeks after the osteotomy procedure, after which the rats were euthanized. Bone healing, bone mineral density, histology, and blood status were analyzed. The results showed that Group 1 (GuaDex) had no ONJ, extensive ongoing bone regeneration, active healing activity, vascularization, and no presence of bacteria. Group 2 (clindamycin) showed early stages of ONJ, avascular areas, and bacteria. Group 3 showed stages of ONJ, inflammatory infiltrates, defective healing, and bacterial presence, and Group 4 had normal healing activity and no bacterial presence. Conclusion: ZA treatment and bacterial inoculation after tooth extraction inhibited bone remodeling/healing and induced ONJ characteristic lesions in the rats. Only GuaDex apparently prevented ONJ development, stimulated bone remodeling, and provided an antimicrobial effect.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Ratos Wistar , Animais , Masculino , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/prevenção & controle , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/patologia , Ratos , Difosfonatos/farmacologia , Difosfonatos/efeitos adversos , Guanidinas/farmacologia , Guanidinas/uso terapêutico
18.
Mar Pollut Bull ; 205: 116573, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38878415

RESUMO

Elasmobranchs are good indicators of marine pollution as they accumulate pollutants from water and food, and occupy different trophic levels. Concentrations of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and chlorpyrifos were quantified in muscle, liver, gonads, gills, and brain in both sexes and maturity stages of the Southern Eagle Ray, Myliobatis goodei, captured in Argentine coastal waters. Moreover, possible histological alterations in the liver and gonads were analyzed. Pollutant concentrations were pervasive across all tissues, with PCBs > OCPs > chlorpyrifos. Elevated pollutant levels were notably found in the liver and gills. We identified thirty-six PCB congeners in tissues, with low-chlorine congeners prevailing. Among OCPs, ∑DDT and ∑endosulfan were predominant. Females exhibited higher pollutant levels in most tissues compared to males, except in the gonads, and adults generally displayed elevated pollutant levels. Histological analysis revealed the presence of atretic follicles and melanomacrophages (MM). Continuous monitoring of pollutant levels, alongside their effects on physiological and ecological traits, is imperative for effective management and conservation efforts.


Assuntos
Clorpirifos , Monitoramento Ambiental , Gônadas , Hidrocarbonetos Clorados , Bifenilos Policlorados , Rajidae , Poluentes Químicos da Água , Animais , Clorpirifos/análise , Poluentes Químicos da Água/análise , Bifenilos Policlorados/metabolismo , Bifenilos Policlorados/análise , Feminino , Masculino , Hidrocarbonetos Clorados/metabolismo , Praguicidas/metabolismo , Fígado , Brânquias , Argentina
19.
Phys Chem Chem Phys ; 26(19): 14393-14406, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38712786

RESUMO

Smart water injection is a technology that allows changing the wettability of the oil rock by injecting water at different salinities, in a cheap and environmentally friendly way compared to other traditional methods. In this study, the individual effect of some typical salts on the wettability of the (104) surface of calcite toward non-polar and polar crude oil models was explored by molecular dynamics as a function of the salinity and pH. The results obtained show that the electrical double layer plays a principal role in the detachment of crude oil models. The divalent ion salts, i.e., CaCl2, CaSO4, MgCl2, and MgSO4, do not form the electrical double layer on calcite, but salts of NaCl and Na2SO4 form it. Moreover, the surface affinity of calcite to the non-polar crude oil is not affected by the salinity. However, the affinity of the calcite surface toward polar crude is affected by salinity and pH conditions. This research provides new insights into the action mechanisms that could help optimize its uses in enhanced oil recovery.

20.
Postgrad Med ; 136(4): 358-365, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38795063

RESUMO

Hiatal hernia (HH) is a common disease in the general population. It is often asymptomatic, but if it does present clinical manifestations, these are usually gastrointestinal. Gastroesophageal reflux is the main symptom that accompanies it. Depending on the severity of the hernia, it is classified into several subtypes from I-IV. Especially, IV type (giant HH) can lead to various cardiopulmonary symptoms with several degrees of severity. It is necessary to keep this possibility in mind among the various differential diagnoses that may occur in this clinical setting. The current paper aims to review the literature on classic and novel information on the HH - cardiovascular system relationship. Epidemiological data, physiological aspects of the heart compressed by HH, cardiovascular symptoms, electrocardiographic changes, echocardiographic alterations and clinical implications are discussed.


Normally, the stomach and the heart are not in direct contact because they are in different cavities, the thorax and the abdomen, respectively. When part of the stomach moves toward the chest through the diaphragm, we say there is a hiatal hernia (HH). Most of the time the HH symptoms are mild and clearly digestive. In severe cases, surgical repair of the HH is required. Even in these circumstances, digestive symptoms continue to be the most frequent. However, some patients present cardiovascular symptoms and few or no digestive symptoms. This easily creates diagnostic confusion, which leads to incorrect treatments and unnecessary expenses. In extreme cases, as seen in giant HH, the degree of cardiovascular involvement is very serious. There are documented cases that have suffered cardiac arrest, arrhythmias of different types and symptoms like classic acute myocardial infarction. It is required that clinical doctors and surgeons are aware that this complication exists. Only with this in mind can a timely diagnosis be achieved. Some emergency measures have been saving, gastric decompression with a tube being the most important. The main mechanism that explains the serious cardiovascular consequences of giant HH is cardiac compression. The dissemination of this knowledge can help save lives.


Assuntos
Refluxo Gastroesofágico , Hérnia Hiatal , Hérnia Hiatal/complicações , Humanos , Refluxo Gastroesofágico/fisiopatologia , Refluxo Gastroesofágico/diagnóstico , Refluxo Gastroesofágico/complicações , Eletrocardiografia/métodos , Ecocardiografia/métodos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/fisiopatologia , Índice de Gravidade de Doença
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