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BACKGROUND & AIMS: Endoscopic sphincterotomy (ES) is not mandatory before biliary stenting. The impact of ES before biliary stent placement remains uncertain. Previous studies have reported that ES can increase adverse event rates by up to 4.5 times compared to no ES. We aimed to assess the occurrence of post-ERCP adverse events following biliary stent placement with and without ES. METHODS: PubMed, Embase, and Cochrane were systematically searched for randomized controlled trials. The primary outcome was post-ERCP pancreatitis (PEP). Subgroup analyses were performed with patients undergoing biliary drainage due to obstruction, using metal stents, and using plastic stents. Secondary outcomes included were post-procedure bleeding, perforation, stent/catheter occlusion, stent/catheter migration, and cholangitis. Heterogeneity was examined using I2 statistics, and a random-effects model was employed. Review manager 5.4 was used for statistical analyses. RESULTS: Seven RCTs with 1,022 patients were included. There was no significant difference between ES and non-ES groups (OR 0.46; 95% 0.19 to 1.09; p = 0.08; I2 = 59%) regarding PEP; however, a significant difference in bleeding rates was found between groups, favoring non-ES (OR 7.55; 95% CI 2.46 to 23.21; p = 0.0004; I2 = 0%). The analysis of the occurrence of cholangitis (OR 1.25; 95% CI 0.58 to 2.69; p = 0.56; I2 = 67%); perforation (OR 1.95; 95% CI 0.07 to 55.73; p = 0.70; I2 = 58%); stent/catheter migration (OR 1.95; 95% CI 0.07 to 55.73; p = 0.23; I2 = 6%); and stent/catheter occlusion (OR 0.90; 95% CI 0.37 to 2.19; p = 0.81; I2 = 0%) did not favor either group. CONCLUSION: Performing ES before biliary drainage does not impact the PEP rate but is associated with an increased postprocedure bleeding rate.
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INTRODUCTION AND OBJECTIVES: Liver transplantation is the optimal treatment for patients with early hepatocellular carcinoma and cirrhosis. However, hepatocellular carcinoma recurs in approximately 15 % of individuals. This study aimed to assess the efficacy of predictive models for hepatocellular carcinoma recurrence after liver transplantation. PATIENTS AND METHODS: This retrospective study included 381 patients with HCC and evaluated the performance of the following models: R3-AFP score, alpha-fetoprotein (AFP) model, University of California, Los Angeles (UCLA) nomogram, Pre-Model of Recurrence after Liver Transplantation (MORAL), Post-MORAL, and Combo MORAL models, Risk Estimation of Tumor Recurrence (RETREAT) model and Platelet to Lymphocyte Ratio (PLR) model. RESULTS: The R3-AFP score, UCLA nomogram, AFP model, RETREAT, Combo MORAL, and Post-MORAL models exhibited comparable AUROCs, ranging from 0.785 to 0.733. The AUROCs for the R3-AFP model and AFP model were superior to those of the Pre-MORAL and PLR models. The UCLA nomogram, RETREAT score, Combo MORAL model, and Post-MORAL model performed similarly to the first two models, but were only superior to the PLR model. CONCLUSIONS: The R3-AFP model, UCLA nomogram, AFP model, RETREAT, Combo MORAL, and Post-MORAL models demonstrated a moderate predictive capacity for hepatocellular carcinoma recurrence following transplantation. No significant differences were observed among these models in their ability to predict recurrence.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Trasplante de Hígado , Humanos , Carcinoma Hepatocelular/patología , alfa-Fetoproteínas , Neoplasias Hepáticas/patología , Trasplante de Hígado/efectos adversos , Estudios Retrospectivos , Factores de Riesgo , Recurrencia Local de NeoplasiaRESUMEN
Biological systems have a remarkable capability of synthesizing multifunctional materials that are adapted for specific physiological and ecological needs. When exploring structure-function relationships related to multifunctionality in nature, it can be a challenging task to address performance synergies, trade-offs, and the relative importance of different functions in biological materials, which, in turn, can hinder our ability to successfully develop their synthetic bioinspired counterparts. Here, we investigate such relationships between the mechanical and optical properties in a multifunctional biological material found in the highly protective yet conspicuously colored exoskeleton of the flower beetle, Torynorrhina flammea Combining experimental, computational, and theoretical approaches, we demonstrate that a micropillar-reinforced photonic multilayer in the beetle's exoskeleton simultaneously enhances mechanical robustness and optical appearance, giving rise to optical damage tolerance. Compared with plain multilayer structures, stiffer vertical micropillars increase stiffness and elastic recovery, restrain the formation of shear bands, and enhance delamination resistance. The micropillars also scatter the reflected light at larger polar angles, enhancing the first optical diffraction order, which makes the reflected color visible from a wider range of viewing angles. The synergistic effect of the improved angular reflectivity and damage localization capability contributes to the optical damage tolerance. Our systematic structural analysis of T. flammea's different color polymorphs and parametric optical and mechanical modeling further suggest that the beetle's microarchitecture is optimized toward maximizing the first-order optical diffraction rather than its mechanical stiffness. These findings shed light on material-level design strategies utilized in biological systems for achieving multifunctionality and could thus inform bioinspired material innovations.
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Exoesqueleto/anatomía & histología , Exoesqueleto/fisiología , Escarabajos/anatomía & histología , Escarabajos/fisiología , Flores/parasitología , Fenómenos Ópticos , Animales , Fenómenos Biomecánicos , Modelos Biológicos , Fotones , Pigmentación , Dispersión de RadiaciónRESUMEN
The objectives of this study were to evaluate the acute effects of the sequence order of drop jumps (DJ) and dynamic stretching (DS) on sprinting performances in competitive athletes and to investigate the relationships between post-activation performance enhancement (PAPE) in sprint performance and lower limb power. Thirteen male jumpers and sprinters participated in this study (19 ± 2 years; 177 ± 7 cm; 71.7 ± 5.6 kg). Through a randomized crossover design, the athletes were exposed to three different conditions after a standardized warm-up: DS+DJ, DJ+DS, and control. Sprinting performance over 40 m was analysed with consideration of initial (0 to 20 m) and final acceleration (20 to 40 m) phases. The effect of intervention was examined by two-way repeated-measures of ANOVA. Pearson's correlation test was used to determine the association between PAPE during sprinting and jump performance. There was no effect of any factor on 40-m sprint performance. Meanwhile, the performance at 20-40 m was higher after the DS+DJ condition when compared to baseline (8.79 ± 0.43 vs. 8.91 ± 0.35 m/s; p = 0.015). However, the initial acceleration was worsened in the DJ+DS condition when compared to baseline (6.26 ± 0.25 vs. 6.22 ± 0.26 m/s; p = 0.002). There was a negative correlation between CMJ height and the improvement in final acceleration (r = -0.741; p = 0.004). The use of DS prior to DJ is an effective strategy to improve performance in the final acceleration phase (20-40 m). The athletes with lower levels of lower limb power benefited the most from this PAPE strategy.
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Although the pathogenesis of Parkinson's Disease (PD) is not completely understood, there is a consensus that it can be caused by multifactorial mechanisms involving genetic susceptibility, epigenetic modifications induced by toxins and mitochondrial dysfunction. In the past 20 years, great efforts have been made in order to clarify molecular mechanisms that are risk factors for this disease, as well as to identify bioactive agents for prevention and slowing down of its progression. Nutraceutical products have received substantial interest due to their nutritional, safe and therapeutic effects on several chronic diseases. The aim of this review was to gather the main evidence of the epigenetic mechanisms involved in the neuroprotective effects of phenolic compounds currently under investigation for the treatment of toxin-induced PD. These studies confirm that the neuroprotective actions of polyphenols involve complex epigenetic modulations, demonstrating that the intake of these natural compounds can be a promising, low-cost, pharmacogenomic strategy against the development of PD.
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Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/prevención & control , Polifenoles/farmacología , Nutrigenómica , Epigénesis Genética , Predisposición Genética a la EnfermedadRESUMEN
Extrahepatic manifestations are common in people with hepatitis C virus (HCV). Cognitive changes are pointed out, but the mechanisms are still uncertain. The aim of this systematic review was to analyze studies involving spectroscopic magnetic resonance in people infected with HCV, which also included cognitive tests. The research occurred in six databases (Directory of Open Access Journals, Lilacs, Medcaribe, Medline, Scielo and ScienceDirect) and the selection of studies was carried out in two stages: search for titles and abstracts, then reading of the full articles, excluding those that did not meet the eligibility criteria. 12,888 titles and abstracts were selected, but only 6 articles were included in the review. Impairments in attention, concentration, speed of information processing, memory, verbal fluency and executive functions were identified as well as an increase in the Cho/Cr and mI/Cr ratios and a reduction in the NAA/Cr ratio in some included studies. Longitudinal studies, with more homogeneous samples and methods, as well as with better controlled confounding factors, are necessary to adequately identify the effect of HCV on the brain.
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Trastornos del Conocimiento , Hepatitis C Crónica , Humanos , Hepatitis C Crónica/patología , Imagen por Resonancia Magnética , Encéfalo/patología , CogniciónRESUMEN
Interleukin-33 (IL-33), a member of the interleukin-1(IL-1) family of cytokines, remains poorly understood in the context of human breast cancer and its impact on treatment outcomes. This study aimed to elucidate IL-33 expression patterns within tumor samples from a cohort of Brazilian female breast cancer patients undergoing neoadjuvant chemotherapy while exploring its correlation with clinicopathological markers. In total, 68 samples were meticulously evaluated, with IL-33 expression quantified through a quantitative polymerase chain reaction. The findings revealed a substantial upregulation of IL-33 expression in breast cancer patient samples, specifically within the Triple-negative and Luminal A and B subtypes, when compared to controls (healthy breast tissues). Notably, the Luminal B subtype displayed a marked elevation in IL-33 expression relative to the Luminal A subtype (p < 0.05). Moreover, a progressive surge in IL-33 expression was discerned among Luminal subtype patients with TNM 4 staging criteria, further underscoring its significance (p < 0.005). Furthermore, chemotherapy-naïve patients of Luminal A and B subtypes exhibited heightened IL-33 expression (p < 0.05). Collectively, our findings propose that chemotherapy could potentially mitigate tumor aggressiveness by suppressing IL-33 expression in breast cancer, thus warranting consideration as a prognostic marker for gauging chemotherapy response and predicting disease progression in Luminal subtype patients. This study not only sheds light on the intricate roles of IL-33 in breast cancer but also offers valuable insights for future IL-33-related research endeavors within this context.
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Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/metabolismo , Interleucina-33/genética , Interleucina-33/uso terapéutico , Terapia Neoadyuvante , Brasil , Resultado del Tratamiento , Biomarcadores de Tumor , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Receptor ErbB-2/metabolismoRESUMEN
This systematic review aims to evaluate the influence of environmental enrichment (EE) on oncological factors in experimental studies involving various types of cancer models. A comprehensive search was conducted in three databases: PubMed (161 articles), Embase (335 articles), and Scopus (274 articles). Eligibility criteria were applied based on the PICOS strategy to minimize bias. Two independent researchers performed the searches, with a third participant resolving any discrepancies. The selected articles were analyzed, and data regarding sample characteristics and EE protocols were extracted. The outcomes focused solely on cancer and tumor-related parameters, including cancer type, description of the cancer model, angiogenesis, tumor occurrence, volume, weight, mice with tumors, and tumor inhibition rate. A total of 770 articles were identified across the three databases, with 12 studies meeting the inclusion criteria for this systematic review. The findings demonstrated that different EE protocols were effective in significantly reducing various aspects of tumor growth and development, such as angiogenesis, volume, weight, and the number of mice with tumors. Furthermore, EE enhanced the rate of tumor inhibition in mouse cancer models. This systematic review qualitatively demonstrates the impacts of EE protocols on multiple parameters associated with tumor growth and development, including angiogenesis, occurrence, volume, weight, and tumor incidence. Moreover, EE demonstrated the potential to increase the rate of tumor inhibition. These findings underscore the importance of EE as a valuable tool in the management of cancer.
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Neoplasias , Humanos , Ratones , Animales , Modelos Animales de Enfermedad , Oncología MédicaRESUMEN
BACKGROUND: During invasive procedures involving needles, there is a chance of damage to peripheral nerves. Therefore, a method for experimentally simulating these situations is needed. OBJECTIVES: In this study we aimed to evaluate peripheral nerve lesions caused by the entry and exit of an injection needle, nerve transfixion through a suture stitch, and the injection of saline solution and lidocaine into the nerve. METHODS: After obtaining approval from the Animal Ethics Committee, we randomly divided 36 Wistar rats, weighing approximately 250 g each, into 6 groups (control, sham, suture, needle, saline, and lidocaine groups), with 6 animals in each group. All procedures were performed on the left paws of the rats. After the procedure, walking track analysis was performed to assess the walking function of rats for 8 weeks. Four months after the procedures, we performed bilateral electrophysiological studies (measuring the latency and amplitude of the electrical impulse in the peroneal nerve). Subsequently, the rats were euthanized, and bilateral tissue samples were collected from the peroneal nerve and tibialis cranialis muscle for morphometric histological analysis. RESULTS: In the walking track analysis, all groups showed normalization of walking functionality after 13 days. There was little histological change between the groups, and no functional loss related to the procedures was observed. CONCLUSIONS: Procedures involving the infusion of local anesthetic or saline solution, or suture needles, are safe with regard to peripheral nerve function loss. Accidents tend not to cause nerve impairment.
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Warm-up protocols with high intensities before continuous running provide potential benefits for middle-distance runners. Nevertheless, the effect of high-intensity warm-ups on long-distance runners remains unclear. The purpose of this study was to verify the effect of a high-intensity warm-up protocol on 5000 m performance in trained runners. Thirteen male runners (34 ± 10 years, 62 ± 6 kg, 62.7 ± 5.5 ml/kg/min) performed two 5000 m time trials, preceded by two different warm-ups. One high-intensity warm up (HIWU: 1x 500 m (70% of the running intensity) + 3x 250 m (100% of the running intensity) and one low-intensity warm up (LIWU: 1x 500 m (70% of the running intensity) + 3x 250 m (70% of the running intensity)), where the running intensities were calculated using the results obtained in the Cooper test. Physiological and metabolic responses, and endurance running performance parameters, were evaluated by the Counter Movement Jump (CMJ), running rating of perceived exertion (RPE), blood lactate concentration (BLa), and performance running. Total time for the 5000 m was lower using HIWU when compared to LIWU (1141.4 ± 110.4 s vs. 1147.8 ± 111.0 s; p = 0.03; Hedges' g = 0.66). The HIWU warm-up led to an improvement in pacing strategy during the time trial. After warm-up protocols, the performance on the CMJ was improved only when applying HIWU (p = 0.008). Post warm-up BLa was significantly higher for HIWU vs. LIWU (3.5 ± 1.0 mmol·L-1 vs. 2.3 ± 1.0 mmol·L-1; p = 0.02), with similar behavior for the RPE (p = 0.002), internal load of the session (p = 0.03). The study showed that a high-intensity warm-up protocol can improve performance in the 5000 m in trained endurance runners.
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Ejercicio de Calentamiento , Humanos , Masculino , Ácido Láctico , MovimientoRESUMEN
The predominantly deep-sea hexactinellid sponges are known for their ability to construct remarkably complex skeletons from amorphous hydrated silica. The skeletal system of one such species of sponge, Euplectella aspergillum, consists of a square-grid-like architecture overlaid with a double set of diagonal bracings, creating a chequerboard-like pattern of open and closed cells. Here, using a combination of finite element simulations and mechanical tests on 3D-printed specimens of different lattice geometries, we show that the sponge's diagonal reinforcement strategy achieves the highest buckling resistance for a given amount of material. Furthermore, using an evolutionary optimization algorithm, we show that our sponge-inspired lattice geometry approaches the optimum material distribution for the design space considered. Our results demonstrate that lessons learned from the study of sponge skeletal systems can be exploited for the realization of square lattice geometries that are geometrically optimized to avoid global structural buckling, with implications for improved material use in modern infrastructural applications.
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Environmental Enrichment (EE) is based on the promotion of socio-environmental stimuli, which mimic favorable environmental conditions for the practice of physical activity and health. The objective of the present systematic review was to evaluate the influence of EE on pro-and anti-inflammatory immune parameters, but also in cell activation related to the innate and acquired immune responses in the brain and peripheral tissues in rodents. Three databases [PubMed (2209 articles), Scopus (1154 articles), and Science Direct (1040 articles)] were researched. After applying the eligibility criteria, articles were selected for peer review, independently, as they were identified by September 2021. The protocol for this systematic review was registered in the PROSPERO. Of the 4417 articles found, 16 were selected for this systematic review. In the brain, EE promoted a reduction in proinflammatory cytokines and chemokines. In the blood, EE promoted a higher percentage of leukocytes, an increase in CD19+ B lymphocytes, and the proliferation of Natura Killer (NK cells). In the bone marrow, there was an increase in the number of CD27- and CD11b+ mature NK cells and a reduction in CD27- and CD11b+ immature Natural Killer cells. In conclusion, EE can be an immune modulation approach and plays a key role in the prevention of numerous chronic diseases, including cancer, that have a pro-inflammatory response and immunosuppressive condition as part of their pathophysiology.
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Citocinas , Roedores , Animales , Médula Ósea , Células Asesinas NaturalesRESUMEN
Environmental factors interfere in the neural plasticity processes. Among these, malnutrition in the early stages of life stands out as one of the main non-genetic factors that can interfere in the morphofunctional development of the nervous system. Furthermore, sensory stimulation from enriched environments (EE) also interferes with neural development. These two factors can modify areas related to memory and learning as the hippocampus, through mechanisms related to the gene expression of brain-derived neurotrophic factor (BDNF). The BDNF may interfere in synaptic plasticity processes, such as memory. In addition, these changes in early life may affect the functioning of the hippocampus during adulthood through mechanisms mediated by BDNF. Therefore, this study aims to conduct a literature review on the effects of early malnutrition on memory and the relationship between the underlying mechanisms of EE, BDNF gene expression, and memory. In addition, there are studies that demonstrate the effect of EE reversal on exposure to changes in the functioning of hippocampal malnutrition in adult rats that were prematurely malnourished. Thereby, evidence from the scientific literature suggests that the mechanisms of synaptic plasticity in the hippocampus of adult animals are influenced by malnutrition and EE, and these alterations may involve the participation of BDNF as a key regulator in memory processes in the adult animal hippocampus.
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Factor Neurotrófico Derivado del Encéfalo , Desnutrición , Memoria , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Ambiente , Hipocampo/metabolismo , Desnutrición/metabolismo , Plasticidad Neuronal/fisiología , RatasRESUMEN
Brittle stars are known for the high flexibility of their arms, a characteristic required for locomotion, food grasping, and for holding onto a great diversity of substrates. Their high agility is facilitated by the numerous discrete skeletal elements (ossicles) running through the center of each arm and embedded in the skin. While much has been learned regarding the structural diversity of these ossicles, which are important characters for taxonomic purposes, their impact on the arms' range of motion, by contrast, is poorly understood. In the present study, we set out to investigate how ossicle morphology and skeletal organization affect the flexibility of brittle star arms. Here, we present the results of an in-depth analysis of three brittle star species (Ophioplocus esmarki, Ophiopteris papillosa, and Ophiothrix spiculata), chosen for their different ranges of motion, as well as spine size and orientation. Using an integrated approach that combines behavioral studies with parametric modeling, additive manufacturing, micro-computed tomography, scanning electron microscopy, and finite element simulations, we present a high-throughput workflow that provides a fundamental understanding of 3D structure-kinematic relationships in brittle star skeletal systems.
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Equinodermos/anatomía & histología , Equinodermos/ultraestructura , Esqueleto/ultraestructura , Animales , Fenómenos Biomecánicos , Equinodermos/fisiología , Esqueleto/anatomía & histología , Esqueleto/fisiología , Microtomografía por Rayos XRESUMEN
Infections are a frequent complication and a major cause of death among patients with cirrhosis. The important impact of infections in general and especially spontaneous bacterial peritonitis on the course of disease and prognosis of patients with cirrhosis has been recognized for many years. Nevertheless, such importance has recently increased due to the comprehension of infection as one of the most prominent risk factors for patients to develop acute-on-chronic liver failure. Furthermore, the issue of infections in cirrhosis is a focus of increasing attention because of the spreading of multidrug resistant bacteria, which is an emerging concern among physicians assisting patients with cirrhosis. In the present paper, we will review the current epidemiology of infections in patients with cirrhosis and particularly that of infections caused by resistant bacteria, demonstrating the relevance of the subject. Besides, we will discuss the current recommendations on diagnosis and treatment of different kinds of infections, including spontaneous bacterial peritonitis, and we will highlight the importance of knowing local microbiological profiles and choosing empirical antibiotic therapy wisely. Finally, we will debate the existing evidences regarding the role of volume expansion with albumin in patients with cirrhosis and extraperitoneal infections, and that of antibiotic prophylaxis of spontaneous bacterial peritonitis.
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Infecciones Bacterianas/microbiología , Cirrosis Hepática/complicaciones , Peritonitis/microbiología , Albúminas/uso terapéutico , Antibacterianos/uso terapéutico , Infecciones Bacterianas/diagnóstico , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/mortalidad , Farmacorresistencia Bacteriana Múltiple , Fluidoterapia , Humanos , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/mortalidad , Peritonitis/diagnóstico , Peritonitis/tratamiento farmacológico , Peritonitis/mortalidad , Sustitutos del Plasma/uso terapéutico , Medición de Riesgo , Factores de Riesgo , Resultado del TratamientoRESUMEN
Background: Physical exercise (PE) has been associated with increase neuroplasticity, neurotrophic factors, and improvements in brain function. Objective: To evaluate the effects of different PE protocols on neuroplasticity components and brain function in a human and animal model. Methods: We conducted a systematic review process from November 2019 to January 2020 of the following databases: PubMed, ScienceDirect, SciELO, LILACS, and Scopus. A keyword combination referring to PE and neuroplasticity was included as part of a more thorough search process. From an initial number of 20,782 original articles, after reading the titles and abstracts, twenty-one original articles were included. Two investigators evaluated the abstract, the data of the study, the design, the sample size, the participant characteristics, and the PE protocol. Results: PE increases neuroplasticity via neurotrophic factors (BDNF, GDNF, and NGF) and receptor (TrkB and P75NTR) production providing improvements in neuroplasticity, and cognitive function (learning and memory) in human and animal models. Conclusion: PE was effective for increasing the production of neurotrophic factors, cell growth, and proliferation, as well as for improving brain functionality.
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Cognición/fisiología , Ejercicio Físico/fisiología , Aprendizaje/fisiología , Memoria/fisiología , Plasticidad Neuronal/fisiología , Animales , Encéfalo/fisiología , HumanosRESUMEN
Toxoplasmosis in South America presents great health impacts and is a topic of research interest not only because of the severity of native cases but also due to the predominant atypical genotypes of the parasite circulating in this continent. Typically, symptomatic toxoplasmosis is treated with a combination of sulfadiazine (SDZ) and pyrimethamine (PYR). However, some clinical cases present treatment failures due to an inability of the drugs to control the infection or their significant adverse effects, which can lead to treatment interruption. Although resistance/susceptibility to the aforementioned drugs has been well described for clonal strains of Toxoplasma gondii spread to the Northern Hemisphere, less is known about the South American atypical strains. In this study, the effectiveness of SDZ and PYR for the treatment of mice during acute infection with different atypical T. gondii strains was evaluated. Swiss mice were infected with seven T. gondii strains obtained from newborn patients with congenital toxoplasmosis in Brazil. The infected mice were treated with 10-640â¯mg/kg per day of SDZ, 3-200â¯mg/kg per day of PYR, or a combination of both drugs with a lower dosage. The mice were evaluated for parameters including mortality, anti-T. gondii IgG production by ELISA and the presence of brain cysts. In addition, the presence of polymorphisms in the dhps gene was verified by gene sequencing. A descriptive analysis was used to assess the association between susceptibility to SDZ and/or PYR and the genotype. The TgCTBr4 and TgCTBr17 strains (genotype 108) presented lower susceptibility to SDZ or PYR treatment. The TgCTBr1 and TgCTBr25 strains (genotype 206) presented similar susceptibility to PYR but not SDZ treatment. The TgCTBr9 strain (genotype 11) was the only strain with high susceptibility to treatment with both drugs. The TgCTBr13 strain (genotype 208) was not susceptible to treatment with the lower PYR or SDZ doses. The TgCTBR23 strain (genotype 41) was more susceptible to PYR than to SDZ treatment. However, the association of low SDZ and PYR doses showed good efficacy for the treatment of experimental toxoplasmosis with T. gondii atypical strains obtained from newborns in Brazil. A new mutation in the T. gondii dhps gene (I347M) was identified that might be associated with the SDZ low sensitivity profile observed for the TgCTBr4 and TgCTBr17 isolates.
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Antiprotozoarios/uso terapéutico , Pirimetamina/uso terapéutico , Sulfadiazina/uso terapéutico , Toxoplasmosis Animal/tratamiento farmacológico , Toxoplasmosis Congénita/parasitología , Alcohol Deshidrogenasa/genética , Animales , Antiprotozoarios/farmacología , Femenino , Genotipo , Humanos , Recién Nacido , Ratones , Pirimetamina/farmacología , Sulfadiazina/farmacología , Toxoplasma/clasificación , Toxoplasma/efectos de los fármacos , Toxoplasma/genética , Toxoplasma/patogenicidad , Toxoplasmosis Animal/parasitología , Toxoplasmosis Congénita/tratamiento farmacológico , VirulenciaRESUMEN
We demonstrate both numerically and experimentally that geometric frustration in two-dimensional periodic acoustic networks consisting of arrays of narrow air channels can be harnessed to form band gaps (ranges of frequency in which the waves cannot propagate in any direction through the system). While resonant standing wave modes and interferences are ubiquitous in all the analyzed network geometries, we show that they give rise to band gaps only in the geometrically frustrated ones (i.e., those comprising of triangles and pentagons). Our results not only reveal a new mechanism based on geometric frustration to suppress the propagation of pressure waves in specific frequency ranges but also open avenues for the design of a new generation of smart systems that control and manipulate sound and vibrations.