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1.
Acta Cir Bras ; 39: e392224, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38629653

RESUMO

PURPOSE: To evaluate, by quantitative and qualitative methods, the glomerular ultrastructure in Wistar rats fed a cafeteria diet. METHODS: Male Wistar rats were divided into two groups at 21 days of age: control (C, n = 10) and cafeteria diet (CAF, n = 8). The animals were followed up until 5 months of age, followed by euthanasia. The blood, kidneys, and fat deposits--epididymal, retroperitoneal, and subcutaneous--were extracted and analyzed. Data were analyzed by Student's t test, and p < 0.05 was considered statistically significant. RESULTS: The cafeteria diet promoted glucose intolerance, hyperglycemia (p < 0.0001), and deposition of retroperitoneal fat (p < 0.005). Scanning electron microscopy revealed that the length of the foot process was similar in both groups. The quantitative analyses by transmission electron microscopy revealed that the cafeteria diet reduced the thickness of the glomerular basement membrane (p < 0.05). CONCLUSIONS: The intake of lipids and simple carbohydrates were found to be associated with alteration in the glomerular ultrastructure. However, more studies are needed to evaluate not only the effects of high-protein and high-fat diets on components of the glomerular filtration barrier, but also renal physiology.


Assuntos
Dieta , Hiperglicemia , Ratos , Animais , Masculino , Ratos Wistar , Dieta/efeitos adversos , Rim , Dieta Hiperlipídica/efeitos adversos
2.
Neurotox Res ; 42(1): 13, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38332435

RESUMO

Hypoxia plays a significant role in the development of various cerebral diseases, many of which are associated with the potential risk of recurrence due to mitochondrial damage. Conventional drug treatments are not always effective for hypoxia-related brain diseases, necessitating the exploration of alternative compounds. In this study, we investigated the potential of diphenyl diselenide [(PhSe)2] to ameliorate locomotor impairments and mitigate brain mitochondrial dysfunction in zebrafish subjected to hypoxia. Additionally, we explored whether these improvements could confer resistance to recurrent hypoxia. Through a screening process, an appropriate dose of (PhSe)2 was determined, and animals exposed to hypoxia received a single intraperitoneal injection of 100 mg/kg of the compound or vehicle. After 1 h from the injection, evaluations were conducted on locomotor deficits, (PhSe)2 content, mitochondrial electron transport system, and mitochondrial viability in the brain. The animals were subsequently exposed to recurrent hypoxia to assess the latency time to hypoxia symptoms. The findings revealed that (PhSe)2 effectively crossed the blood-brain barrier, attenuated locomotor deficits induced by hypoxia, and improved brain mitochondrial respiration by modulating complex III. Furthermore, it enhanced mitochondrial viability in the telencephalon, contributing to greater resistance to recurrent hypoxia. These results demonstrate the beneficial effects of (PhSe)2 on both hypoxia and recurrent hypoxia, with cerebral mitochondria being a critical target of its action. Considering the involvement of brain hypoxia in numerous pathologies, (PhSe)2 should be further tested to determine its effectiveness as a potential treatment for hypoxia-related brain diseases.


Assuntos
Encefalopatias , Compostos Organosselênicos , Animais , Peixe-Zebra , Mitocôndrias , Derivados de Benzeno/farmacologia , Derivados de Benzeno/uso terapêutico , Compostos Organosselênicos/farmacologia , Compostos Organosselênicos/uso terapêutico , Hipóxia/tratamento farmacológico
3.
Neurobiol Aging ; 136: 88-98, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38335912

RESUMO

Understanding whether vascular risk factors (VRFs) synergistically potentiate Alzheimer's disease (AD) progression is important in the context of emerging treatments for preclinical AD. In a group of 503 cognitively unimpaired individuals, we tested whether VRF burden interacts with AD pathophysiology to accelerate neurodegeneration and cognitive decline. Baseline VRF burden was calculated considering medical data and AD pathophysiology was assessed based on cerebrospinal fluid (CSF) amyloid-ß1-42 (Aß1-42) and tau phosphorylated at threonine 181 (p-tau181). Neurodegeneration was assessed with plasma neurofilament light (NfL) and global cognition with the modified version of the Preclinical Alzheimer's Cognitive Composite. The mean (SD) age of participants was 72.9 (6.1) years, and 220 (43.7%) were men. Linear mixed-effects models revealed that an elevated VRF burden synergistically interacted with AD pathophysiology to drive longitudinal plasma NfL increase and cognitive decline. Additionally, VRF burden was not associated with CSF Aß1-42 or p-tau181 changes over time. Our results suggest that VRF burden and AD pathophysiology are independent processes; however, they synergistically lead to neurodegeneration and cognitive deterioration. In preclinical stages, the combination of therapies targeting VRFs and AD pathophysiology might potentiate treatment outcomes.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Masculino , Humanos , Idoso , Feminino , Proteínas tau/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Cognição/fisiologia , Progressão da Doença
4.
Mol Psychiatry ; 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38366114

RESUMO

Glutamatergic neurotransmission system dysregulation may play an important role in the pathophysiology of Alzheimer's disease (AD). However, reported results on glutamatergic components across brain regions are contradictory. Here, we conducted a systematic review with meta-analysis to examine whether there are consistent glutamatergic abnormalities in the human AD brain. We searched PubMed and Web of Science (database origin-October 2023) reports evaluating glutamate, glutamine, glutaminase, glutamine synthetase, glutamate reuptake, aspartate, excitatory amino acid transporters, vesicular glutamate transporters, glycine, D-serine, metabotropic and ionotropic glutamate receptors in the AD human brain (PROSPERO #CDRD42022299518). The studies were synthesized by outcome and brain region. We included cortical regions, the whole brain (cortical and subcortical regions combined), the entorhinal cortex and the hippocampus. Pooled effect sizes were determined with standardized mean differences (SMD), random effects adjusted by false discovery rate, and heterogeneity was examined by I2 statistics. The search retrieved 6 936 articles, 63 meeting the inclusion criteria (N = 709CN/786AD; mean age 75/79). We showed that the brain of AD individuals presents decreased glutamate (SMD = -0.82; I2 = 74.54%; P < 0.001) and aspartate levels (SMD = -0.64; I2 = 89.71%; P = 0.006), and reuptake (SMD = -0.75; I2 = 83.04%; P < 0.001. We also found reduced α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPAR)-GluA2/3 levels (SMD = -0.63; I2 = 95.55%; P = 0.046), hypofunctional N-methyl-D-aspartate receptor (NMDAR) (SMD = -0.60; I2 = 91.47%; P < 0.001) and selective reduction of NMDAR-GluN2B subunit levels (SMD = -1.07; I2 = 41.81%; P < 0.001). Regional differences include lower glutamate levels in cortical areas and aspartate levels in cortical areas and in the hippocampus, reduced glutamate reuptake, reduced AMPAR-GluA2/3 in the entorhinal cortex, hypofunction of NMDAR in cortical areas, and a decrease in NMDAR-GluN2B subunit levels in the entorhinal cortex and hippocampus. Other parameters studied were not altered. Our findings show depletion of the glutamatergic system and emphasize the importance of understanding glutamate-mediated neurotoxicity in AD. This study has implications for the development of therapies and biomarkers in AD.

5.
Chaos ; 34(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38341761

RESUMO

The description of neuronal activity has been of great importance in neuroscience. In this field, mathematical models are useful to describe the electrophysical behavior of neurons. One successful model used for this purpose is the Adaptive Exponential Integrate-and-Fire (Adex), which is composed of two ordinary differential equations. Usually, this model is considered in the standard formulation, i.e., with integer order derivatives. In this work, we propose and study the fractal extension of Adex model, which in simple terms corresponds to replacing the integer derivative by non-integer. As non-integer operators, we choose the fractal derivatives. We explore the effects of equal and different orders of fractal derivatives in the firing patterns and mean frequency of the neuron described by the Adex model. Previous results suggest that fractal derivatives can provide a more realistic representation due to the fact that the standard operators are generalized. Our findings show that the fractal order influences the inter-spike intervals and changes the mean firing frequency. In addition, the firing patterns depend not only on the neuronal parameters but also on the order of respective fractal operators. As our main conclusion, the fractal order below the unit value increases the influence of the adaptation mechanism in the spike firing patterns.


Assuntos
Fractais , Modelos Neurológicos , Potenciais de Ação/fisiologia , Neurônios/fisiologia
6.
Histol Histopathol ; 39(8): 1009-1015, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38221876

RESUMO

Exposure to prolonged stress in pregnancy and/or lactation can lead to the future development of diseases. We aimed to study the effects of maternal stress on the biometry, metabolism, and penile morphology of young Wistar rats. Animals were divided into two experimental groups: Control Group (C) - pups from control mothers, without any intervention (n=5); and Chronic Stress Group (S) - pups from mothers who suffered variable stress in the third week of pregnancy (14th to 21st day; n=5). Food intake and body mass of the pups (n=10, in the C group and n=9 in the S group) were checked; at euthanasia (three months old), fat deposits and penis were removed. At birth and weaning, S animals were lighter than C animals, [-33.72% (p=0.0422) and -17.07% (p=0.0018)], respectively. However, the final body mass and body mass delta showed no differences. Food intake and fat deposits also did not differ. However, the S group was hyperglycemic at 30 and 60 days of life [+20.59% (p=0.0042) and +14.56% (p=0.0079), respectively], despite the glycemia measured at 90 days showing no difference between groups. Penile areas and surface densities of the corpora cavernosa components were similar between groups. The results indicate that maternal stress is an important metabolic programmer, which generates low birth weight and accelerated recovery of body mass after birth (catch-up). However, in an early analysis (90 days of life), exposure to gestational stress did not change the morphology of the offspring's penis in adulthood.


Assuntos
Pênis , Efeitos Tardios da Exposição Pré-Natal , Ratos Wistar , Estresse Psicológico , Animais , Masculino , Feminino , Gravidez , Pênis/metabolismo , Ratos , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/patologia , Estresse Psicológico/metabolismo , Animais Recém-Nascidos , Peso Corporal
7.
Biochimie ; 219: 21-32, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37541567

RESUMO

Non ketotic hyperglycinemia (NKH) is an inborn error of glycine metabolism caused by mutations in the genes encoding glycine cleavage system proteins. Classic NKH has a neonatal onset, and patients present with severe neurodegeneration. Although glycine accumulation has been implicated in NKH pathophysiology, the exact mechanisms underlying the neurological damage and white matter alterations remain unclear. We investigated the effects of glycine in the brain of neonatal rats and MO3.13 oligodendroglial cells. Glycine decreased myelin basic protein (MBP) and myelin-associated glycoprotein (MAG) in the corpus callosum and striatum of rats on post-natal day (PND) 15. Glycine also reduced neuroglycan 2 (NG2) and N-methyl-d-aspartate receptor subunit 1 (NR1) in the cerebral cortex and striatum on PND15. Moreover, glycine reduced striatal glutamate aspartate transporter 1 (GLAST) content and neuronal nucleus (NeuN), and increased glial fibrillary acidic protein (GFAP) on PND15. Glycine also increased DCFH oxidation and malondialdehyde levels and decreased GSH concentrations in the cerebral cortex and striatum on PND6, but not on PND15. Glycine further reduced viability but did not alter DCFH oxidation and GSH levels in MO3.13 cells after 48- and 72-h incubation. These data indicate that impairment of myelin structure and glutamatergic system and induction of oxidative stress are involved in the neuropathophysiology of NKH.


Assuntos
Hiperglicinemia não Cetótica , Humanos , Animais , Ratos , Hiperglicinemia não Cetótica/genética , Hiperglicinemia não Cetótica/metabolismo , Glicina , Bainha de Mielina/metabolismo , Oxirredução , Transmissão Sináptica , Homeostase
8.
Neurochem Res ; 49(3): 732-743, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38063948

RESUMO

Astrocytes have key regulatory roles in central nervous system (CNS), integrating metabolic, inflammatory and synaptic responses. In this regard, type I interferon (IFN) receptor signaling in astrocytes can regulate synaptic plasticity. Simvastatin is a cholesterol-lowering drug that has shown anti-inflammatory properties, but its effects on astrocytes, a main source of cholesterol for neurons, remain to be elucidated. Herein, we investigated the effects of simvastatin in inflammatory and functional parameters of primary cortical and hypothalamic astrocyte cultures obtained from IFNα/ß receptor knockout (IFNα/ßR-/-) mice. Overall, simvastatin decreased extracellular levels of tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß), which were related to a downregulation in gene expression in hypothalamic, but not in cortical astrocytes. Moreover, there was an increase in anti-inflammatory interleukin-10 (IL-10) in both structures. Effects of simvastatin in inflammatory signaling also involved a downregulation of cyclooxygenase 2 (COX-2) gene expression as well as an upregulation of nuclear factor κB subunit p65 (NFκB p65). The expression of cytoprotective genes sirtuin 1 (SIRT1) and nuclear factor erythroid derived 2 like 2 (Nrf2) was also increased by simvastatin. In addition, simvastatin increased glutamine synthetase (GS) activity and glutathione (GSH) levels only in cortical astrocytes. Our findings provide evidence that astrocytes from different regions are important cellular targets of simvastatin in the CNS, even in the absence of IFNα/ßR, which was showed by the modulation of cytokine production and release, as well as the expression of cytoprotective genes and functional parameters.


Assuntos
Astrócitos , Sinvastatina , Camundongos , Animais , Astrócitos/metabolismo , Sinvastatina/farmacologia , Camundongos Knockout , Fator de Necrose Tumoral alfa/metabolismo , Interferon-alfa/metabolismo , Interferon-alfa/farmacologia , Anti-Inflamatórios/farmacologia , Colesterol/metabolismo , Células Cultivadas
9.
Acta cir. bras ; 39: e392224, 2024. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1556673

RESUMO

Purpose: To evaluate, by quantitative and qualitative methods, the glomerular ultrastructure in Wistar rats fed a cafeteria diet. Methods: Male Wistar rats were divided into two groups at 21 days of age: control (C, n = 10) and cafeteria diet (CAF, n = 8). The animals were followed up until 5 months of age, followed by euthanasia. The blood, kidneys, and fat deposits­­epididymal, retroperitoneal, and subcutaneous­­were extracted and analyzed. Data were analyzed by Student's t test, and p < 0.05 was considered statistically significant. Results: The cafeteria diet promoted glucose intolerance, hyperglycemia (p < 0.0001), and deposition of retroperitoneal fat (p < 0.005). Scanning electron microscopy revealed that the length of the foot process was similar in both groups. The quantitative analyses by transmission electron microscopy revealed that the cafeteria diet reduced the thickness of the glomerular basement membrane (p < 0.05). Conclusions: The intake of lipids and simple carbohydrates were found to be associated with alteration in the glomerular ultrastructure. However, more studies are needed to evaluate not only the effects of high-protein and high-fat diets on components of the glomerular filtration barrier, but also renal physiology.


Assuntos
Animais , Ratos , Microscopia Eletrônica de Varredura , Ratos Wistar , Dieta , Rim
11.
Acta Cir Bras ; 38: e387123, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38055386

RESUMO

PURPOSE: To investigate the effects of chronic stress in the prostate of prepubertal and adult rats. METHODS: Thirty-two male rats were assigned into four groups depending on the type of treatment (control or stressed) and the age at which stress was initiated (prepubertal or adult). Restraint stress stimuli were applied for six weeks. Stressed prepubertal and adult rats evaluated immediately after the last stress stimuli were named SP and SA groups, respectively. Age-matched rats were used as control groups (CP and CA). At the end of the experiment, the rats were euthanized, and prostate morphological parameters were evaluated and statistically compared. RESULTS: Application of stress stimuli to the SP group resulted in reduced body weight, but no prostate morphological modification was noted. The SA group showed reduced testosterone level and prostatic epithelium surface density, in comparison to CA group. Further, the prostatic lumen surface density was increased in adult stressed animals, in comparison to adult controls. CONCLUSIONS: The stress stimuli promoted changes in hormonal and morphological parameters in the prostate of adult stressed rats. Prepubertal stressed animals did not presented modifications of prostate morphology.


Assuntos
Próstata , Estresse Psicológico , Ratos , Animais , Masculino
12.
Mol Neurobiol ; 2023 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-37980327

RESUMO

Metformin, a biguanide compound (N-1,1-dimethylbiguanide), is widely prescribed for diabetes mellitus type 2 (T2D) treatment. It also presents a plethora of properties, such as anti-oxidant, anti-inflammatory, anti-apoptosis, anti-tumorigenic, and anti-AGE formation activity. However, the precise mechanism of action of metformin in the central nervous system (CNS) needs to be clarified. Herein, we investigated the neuroprotective role of metformin in acute hippocampal slices exposed to methylglyoxal (MG), a highly reactive dicarbonyl compound and a key molecule in T2D developmental pathophysiology. Metformin protected acute hippocampal slices from MG-induced glutamatergic neurotoxicity and neuroinflammation by reducing IL-1ß synthesis and secretion and RAGE protein expression. The drug also improved astrocyte function, particularly with regard to the glutamatergic system, increasing glutamate uptake. Moreover, we observed a direct effect of metformin on glutamate transporters, where the compound prevented glycation, by facilitating enzymatic phosphorylation close to Lys residues, suggesting a new neuroprotective role of metformin via PKC ζ in preventing dysfunction in glutamatergic system induced by MG. Proposed neuroprotection role of metformin in acute hippocampal slices against impairment in glutamatergic system induced in a model of methylglyoxal glycotoxicity. Metformin reversed methylglyoxal (MG)-induced neuroinflammation by reducing pro-inflammatory IL-1ß synthesis and secretion and RAGE protein expression. Metformin did not alter the effect of MG on S100B secretion (1). Both MG and metformin also influenced astrocyte function in hippocampal slices. Metformin did not reverse the elevation in GLO1 activity induced by glycotoxicity; however, it abrogated the high GSH level and the expression of the co-factor of GLO1 (2). Both treatments per se changed bioenergetic metabolism and increased glucose uptake, extracellular lactate content, and pyruvate kinase (PK) activity. The increment in glucose uptake and lactate levels ceased during the co-incubation of MG with metformin. Metformin reversed the elevation of hexokinase activity by MG (3). We suggest a new role of metformin in the glutamate system, whereby it protects the hippocampus against the derangements of the glutamatergic system induced by MG, possibly by phosphorylation via PKC ζ (4). The neuroprotective action of metformin may be mediated by the phosphorylation of specific amino acid residues (Lysine) of the glutamate transporters (GLAST and GLT-1), since metformin activated the PKC ζ signaling and promoted cascades of phosphorylation in p38 MAPK and Akt proteins. The transporter protein phosphorylation prevented the Lys-glycation and the impairment of glutamate uptake induced by MG (5).

13.
Stress ; 26(1): 2265160, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37796089

RESUMO

OBJECTIVES: To investigate the effects of chronic stress on bladder morphology and the impact of food preference (standard or comfort foods) on the bladder of stressed rats. METHODS: In total, 32 Wistar male rats (3 months old) were divided into four groups: control (C), stressed (S), control + comfort food (C + CF), and stressed + comfort food (S + CF). Groups C and C + CF were maintained under normal conditions, while groups S and S + CF were subjected to chronic stress by the restraint method. Groups C and S received standard rat chow, while groups C + CF and S + CF received comfort food (Froot Loops®) and standard chow. The stress stimuli were induced daily for 2 h over 8 weeks. After 8 weeks, all animals were killed, and the bladders were removed and used for histomorphometric analysis. RESULTS: Body mass was similar among the groups. Stress did not promote differences regarding food intake, but animals receiving comfort food showed higher calories intake (in kcal/Kg) than animals receiving only standard chow. The C + CF and S + CF groups preferred comfort food over the standard chow; this preference was higher in the S + CF than in the C + CF group. The surface density of smooth muscle was reduced in stressed animals, while connective tissue and elastic system fiber content were increased in stressed groups. Further, epithelial height was increased in rats submitted to chronic stress. The surface density of elastic system fibers was decreased by the consumption of comfort food. CONCLUSIONS: Chronic stress induces morphological modifications on the bladder wall and epithelium. These modifications may be related to lower urinary tract symptoms. Additionally, chronic stress caused a higher preference for comfort food intake which did not ameliorate or aggravate the stress-induced bladder alterations.


Assuntos
Ingestão de Alimentos , Bexiga Urinária , Ratos , Masculino , Animais , Ingestão de Alimentos/fisiologia , Ratos Wistar , Estresse Psicológico , Ingestão de Energia
14.
Arq Gastroenterol ; 60(3): 322-329, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37792761

RESUMO

•The study investigated the prevalence of certain comorbidities in patients with Chagas megaoesophagus compared to those without the condition, aiming to determine whether it serves as a protective or risk factor. •In the general group (546 patients), the three most prevalent comorbidities were hypertension (44.3%), dyslipidaemia (17.8%), and heart failure (15.2%). •In the older group (248 patients), similar to that in the general group, the most prevalent comorbidities were hypertension, dyslipidaemia, and heart failure. •The lower prevalence of diabetes mellitus and Alzheimer's disease in the patients with Chagas megaoesophagus suggests the association of enteric nervous system denervation and requires further investigation. Objective - This study aimed to evaluate the prevalence of some epidemiologically important comorbidities in patients with Chagas megaoesophagus in relation to the population without megaoesophagus, and whether this condition would be a protective or a risk factor for the conditions analysed. Methods - This observational descriptive study collected data from the medical records of patients with a previous diagnosis of megaoesophagus (timing: from 2005 to 2020). The patients were divided by age into a general (all ages) and an older group (aged 60 years or more). Associations were searched for four main areas/systems/involvements: cardiovascular, respiratory, endocrine and neurological. Results - The general group included 546 patients and the older group included 248 patients. As for the prevalence of comorbidities in the general group, the three most prevalent diseases were hypertension, with 44.3% (CI95%: 40.21-48.51%); dyslipidaemia, with 17.8% (CI95%: 14.79-21.19%); and heart failure, with 15.2% (CI95%: 12.43-18.45%). Similar to that in the general group, the most prevalent comorbidities in the group of older patients were hypertension, dyslipidaemia, and heart failure. Conclusion - Systemic arterial hypertension, dyslipidaemia, and heart failure were the most prevalent comorbidities in this population. The lower prevalence of diabetes mellitus and Alzheimer's disease suggests the association of enteric nervous system denervation and requires further investigation.


Assuntos
Doença de Alzheimer , Diabetes Mellitus , Dislipidemias , Acalasia Esofágica , Insuficiência Cardíaca , Hipertensão , Humanos , Acalasia Esofágica/epidemiologia , Doença de Alzheimer/complicações , Doença de Alzheimer/epidemiologia , Prevalência , Comorbidade , Hipertensão/complicações , Hipertensão/epidemiologia , Diabetes Mellitus/epidemiologia , Dislipidemias/epidemiologia , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/complicações
16.
Chaos ; 33(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37712917

RESUMO

This work studies the SIS model extended by fractional and fractal derivatives. We obtain explicit solutions for the standard and fractal formulations; for the fractional case, we study numerical solutions. As a real data example, we consider the Brazilian syphilis data from 2011 to 2021. We fit the data by considering the three variations of the model. Our fit suggests a recovery period of 11.6 days and a reproduction ratio (R0) equal to 6.5. By calculating the correlation coefficient (r) between the real data and the theoretical points, our results suggest that the fractal model presents a higher r compared to the standard or fractional case. The fractal formulation is improved when two different fractal orders with distinguishing weights are considered. This modification in the model provides a better description of the data and improves the correlation coefficient.


Assuntos
Modelos Epidemiológicos , Sífilis , Humanos , Fractais , Brasil
17.
Asian J Androl ; 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37695239

RESUMO

The objective of this study was to investigate whether treatment with Tribulus terrestris (Tt) has any impact on the testicular morphology and function in a rodent model. Twenty male rats were divided into a control group and a group receiving 100 mg kg-1 body weight of Tt supplementation. After 40 days of experiment, the animals were submitted to euthanasia; epididymal tail spermatozoa were collected; and spermatozoa concentration, motility, and viability were analyzed. In addition, testicles were collected and processed for histomorphometrical analyses. Data were compared using the Student's t-test and considered significant when P < 0.05. Spermatozoa concentration, motility, and viability showed no difference between the groups. Further, testicular weight and volume, seminiferous tubule diameter, tunica propria surface density, seminiferous epithelium surface density, and intertubular compartment surface density were statistically similar between the groups. However, seminiferous epithelium height and tubular lumen surface density were augmented in animals treated with Tt. Treatment with Tt does not cause a major impact on testicular morphology, promoting only subtle modifications. No difference on spermatozoa parameters was observed.

18.
Brain Sci ; 13(9)2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37759949

RESUMO

Healthy brains display a wide range of firing patterns, from synchronized oscillations during slow-wave sleep to desynchronized firing during movement. These physiological activities coexist with periods of pathological hyperactivity in the epileptic brain, where neurons can fire in synchronized bursts. Most cortical neurons are pyramidal regular spiking (RS) cells with frequency adaptation and do not exhibit bursts in current-clamp experiments (in vitro). In this work, we investigate the transition mechanism of spike-to-burst patterns due to slow potassium and calcium currents, considering a conductance-based model of a cortical RS cell. The joint influence of potassium and calcium ion channels on high synchronous patterns is investigated for different synaptic couplings (gsyn) and external current inputs (I). Our results suggest that slow potassium currents play an important role in the emergence of high-synchronous activities, as well as in the spike-to-burst firing pattern transitions. This transition is related to the bistable dynamics of the neuronal network, where physiological asynchronous states coexist with pathological burst synchronization. The hysteresis curve of the coefficient of variation of the inter-spike interval demonstrates that a burst can be initiated by firing states with neuronal synchronization. Furthermore, we notice that high-threshold (IL) and low-threshold (IT) ion channels play a role in increasing and decreasing the parameter conditions (gsyn and I) in which bistable dynamics occur, respectively. For high values of IL conductance, a synchronous burst appears when neurons are weakly coupled and receive more external input. On the other hand, when the conductance IT increases, higher coupling and lower I are necessary to produce burst synchronization. In light of our results, we suggest that channel subtype-specific pharmacological interactions can be useful to induce transitions from pathological high bursting states to healthy states.

19.
Nat Aging ; 3(10): 1210-1218, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37749258

RESUMO

The mechanisms by which the apolipoprotein E ε4 (APOEε4) allele influences the pathophysiological progression of Alzheimer's disease (AD) are poorly understood. Here we tested the association of APOEε4 carriership and amyloid-ß (Aß) burden with longitudinal tau pathology. We longitudinally assessed 94 individuals across the aging and AD spectrum who underwent clinical assessments, APOE genotyping, magnetic resonance imaging, positron emission tomography (PET) for Aß ([18F]AZD4694) and tau ([18F]MK-6240) at baseline, as well as a 2-year follow-up tau-PET scan. We found that APOEε4 carriership potentiates Aß effects on longitudinal tau accumulation over 2 years. The APOEε4-potentiated Aß effects on tau-PET burden were mediated by longitudinal plasma phosphorylated tau at threonine 217 (p-tau217+) increase. This longitudinal tau accumulation as measured by PET was accompanied by brain atrophy and clinical decline. Our results suggest that the APOEε4 allele plays a key role in Aß downstream effects on the aggregation of phosphorylated tau in the living human brain.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Apolipoproteína E4 , Heterozigoto , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Proteínas tau/genética , Apolipoproteína E4/genética , Alelos
20.
Arq. gastroenterol ; 60(3): 322-329, July-Sept. 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1513709

RESUMO

ABSTRACT Objective: This study aimed to evaluate the prevalence of some epidemiologically important comorbidities in patients with Chagas megaoesophagus in relation to the population without megaoesophagus, and whether this condition would be a protective or a risk factor for the conditions analysed. Methods: This observational descriptive study collected data from the medical records of patients with a previous diagnosis of megaoesophagus (timing: from 2005 to 2020). The patients were divided by age into a general (all ages) and an older group (aged 60 years or more). Associations were searched for four main areas/systems/involvements: cardiovascular, respiratory, endocrine and neurological. Results: The general group included 546 patients and the older group included 248 patients. As for the prevalence of comorbidities in the general group, the three most prevalent diseases were hypertension, with 44.3% (CI95%: 40.21-48.51%); dyslipidaemia, with 17.8% (CI95%: 14.79-21.19%); and heart failure, with 15.2% (CI95%: 12.43-18.45%). Similar to that in the general group, the most prevalent comorbidities in the group of older patients were hypertension, dyslipidaemia, and heart failure. Conclusion: Systemic arterial hypertension, dyslipidaemia, and heart failure were the most prevalent comorbidities in this population. The lower prevalence of diabetes mellitus and Alzheimer's disease suggests the association of enteric nervous system denervation and requires further investigation.


RESUMO Objetivo: Este estudo teve como objetivo avaliar a prevalência de algumas comorbidades epidemiologicamente importantes em pacientes com megaesôfago chagásico em relação à população sem o megaesôfago e se essa condição seria um fator protetor ou de risco para as condições analisadas. Métodos: Este estudo descritivo observacional coletou dados de prontuários de pacientes com diagnóstico prévio de megaesôfago (período: de 2005 a 2020). Os pacientes foram divididos por idade em um grupo geral (todas as idades) e um grupo idoso (60 anos ou mais). Foram pesquisadas associações para quatro áreas/sistemas/envolvimentos principais: cardiovascular, respiratório, endócrino e neurológico. Resultados: O grupo geral incluiu 546 pacientes e o grupo idosos incluiu 248 pacientes. Quanto à prevalência de comorbidades no grupo geral, as três doenças mais prevalentes foram hipertensão, com 44,3% (IC95%: 40,21-48,51%); dislipidemia, com 17,8% (IC95%: 14,79-21,19%); e insuficiência cardíaca, com 15,2% (IC95%: 12,43-18,45%). Assim como no grupo geral, as comorbidades mais prevalentes no grupo de idosos foram hipertensão, dislipidemia e insuficiência cardíaca. Conclusão: Hipertensão arterial sistêmica, dislipidemia e insuficiência cardíaca foram as comorbidades mais prevalentes nessa população. A menor prevalência de diabetes mellitus e doença de Alzheimer sugere uma associação de denervação do sistema nervoso entérico e requer mais investigação.

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