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1.
Pflugers Arch ; 476(3): 365-377, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38308122

RESUMO

To assess the influence of physical training on neuronal activation and hypothalamic expression of vasopressin and oxytocin in spontaneously hypertensive rats (SHR), untrained and trained normotensive rats and SHR were submitted to running until fatigue while internal body and tail temperatures were recorded. Hypothalamic c-Fos expression was evaluated in thermoregulatory centers such as the median preoptic nucleus (MnPO), medial preoptic nucleus (mPOA), paraventricular nucleus of the hypothalamus (PVN), and supraoptic nucleus (SON). The PVN and the SON were also investigated for vasopressin and oxytocin expressions. Although exercise training improved the workload performed by the animals, it was reduced in SHR and followed by increased internal body temperature due to tail vasodilation deficit. Physical training enhanced c-Fos expression in the MnPO, mPOA, and PVN of both strains, and these responses were attenuated in SHR. Vasopressin immunoreactivity in the PVN was also increased by physical training to a lesser extent in SHR. The already-reduced oxytocin expression in the PVN of SHR was increased in response to physical training. Within the SON, neuronal activation and the expressions of vasopressin and oxytocin were reduced by hypertension and unaffected by physical training. The data indicate that physical training counterbalances in part the negative effect of hypertension on hypothalamic neuronal activation elicited by exercise, as well as on the expression of vasopressin and oxytocin. These hypertension features seem to negatively influence the workload performed by SHR due to the hyperthermia derived from the inability of physical training to improve heat dissipation through skin vasodilation.


Assuntos
Hipertensão , Corrida , Ratos , Animais , Ratos Endogâmicos SHR , Ocitocina/metabolismo , Ocitocina/farmacologia , Hipotálamo/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Vasopressinas/metabolismo , Hipertensão/metabolismo , Fadiga
2.
J Therm Biol ; 123: 103907, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38950497

RESUMO

Recent heatwaves have highlighted the importance of accurate and continuous core temperature (TCORE) monitoring in sports settings. For example, accentuated rises in TCORE caused by physical exercises under environmental heat stress increase the risk of heat illnesses. Thus, using valid and reproducible devices is essential to ensure safe sports practice. In this study, we assessed the validity and reproducibility of the Calera Research Sensor (CRS) in estimating the TCORE of male and female participants during cycling exercise in a hot environment. Seven male (age: 36.2 ± 10.1 years) and eight female cyclists (age: 30.1 ± 5.0 years) underwent two identical cycling trials in a dry-bulb temperature of 32 °C and relative humidity of 60%. The protocol consisted of an initial 10-min rest followed by a 60-min exercise comprising 10 min at 20%, 25 min at 55%, and 25 min at 75% of maximal aerobic power, and an additional 25 min of post-exercise recovery. TCORE was recorded simultaneously every minute using a gastrointestinal capsule (TGi) and the CRS (TSENSOR). Bland-Altman analysis was performed to calculate bias, upper (LCS) and lower (LCI) concordance limits, and the 95% confidence interval (95%CI). The maximum acceptable difference between the two devices was predetermined at ±0.4 °C. A mixed linear model was used to assess the paired differences between the two measurement systems, considering the participants, trials, and environmental conditions as random effects and the cycling stages as fixed effects. An intra-class correlation coefficient (ICC) of 0.98 was recorded when analyzing data from the entire experiment. A non-significant bias value of 0.01 °C, LCS of 0.38 °C, LCI of -0.35 °C, and CI95% of ±0.36 °C were found. When analyzing data according to the participants' sex, CRS reproducibility was high in both sexes: ICC values of 0.98 and 0.99 were reported for males and females, respectively. CI95% was 0.35 °C in experiments with males and 0.37 °C with females, thereby falling within the acceptable margin of difference. Therefore, CRS was considered valid (compared to TGi) and reproducible in estimating TCORE in both sexes at various intensities of cycling exercise in the heat.


Assuntos
Ciclismo , Temperatura Corporal , Temperatura Alta , Humanos , Masculino , Adulto , Feminino , Ciclismo/fisiologia , Reprodutibilidade dos Testes , Exercício Físico , Adulto Jovem
3.
BMC Bioinformatics ; 24(1): 107, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36949402

RESUMO

BACKGROUND: The molecular dynamics is an approach to obtain kinetic and thermodynamic characteristics of biomolecular structures. The molecular dynamics simulation softwares are very useful, however, most of them are used in command line form and continue with the same common implementation difficulties that plague researchers who are not computer specialists. RESULTS: Here, we have developed the VisualDynamics-a WEB tool developed to automate biological simulations performed in Gromacs using a graphical interface to make molecular dynamics simulation user-friendly task. In this new application the researcher can submit a simulation of the protein in the free form or complexed with a ligand. Can also download the graphics analysis and log files at the end of the simulation. CONCLUSIONS: VisualDynamics is a tool that will accelerate implementations and learning in the area of molecular dynamics simulation. Freely available at https://visualdynamics.fiocruz.br/login , is supported by all major web browsers. VisualDynamics was developed with Flask, which is a Python-based free and open-source framework for web development. The code is freely available for download at GitHub https://github.com/LABIOQUIM/visualdynamics .


Assuntos
Simulação de Dinâmica Molecular , Software , Proteínas/química , Cinética , Navegador
4.
J Therm Biol ; 97: 102807, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33863423

RESUMO

The purpose of this study was to evaluate the circadian rhythm of core temperature (Tcore) across aging in Spontaneously Hypertensive Rats (SHR) with comparison to the two rat strains often used as their normotensive control animals, namely, Wistar (WIS) and Wistar Kyoto (WKY). METHODS: WIS, WKY and SHR rats were subdivided into three different groups according their age: WIS16, WIS48, WIS72, WKY16, WKY48, WKY72, SHR16, SHR48 and SHR72 weeks-old. Body mass and blood pressure were periodically measured along the experiments. All animal group had their circadian rhythm of Tcore evaluated over three consecutive days (72 h) by telemetry using an implanted temperature sensor. The Tcore circadian rhythm was averaged in 1-h blocks and analyzed using the cosinor method. RESULTS: Sixteen-week-old SHR (SHR16) presented higher Tcore than WIS16 (from 06am to 06pm) and WKY16 (from 07am to 06pm). Both normotensive groups exhibited increases in Tcore during circadian rhythm with aging. The cosinor analysis showed no differences between strains and ages for the acrophase. An age effect on the SHR strain (SHR16 < SHR72) was observed regarding the amplitude. SHR16 had higher values regarding MESOR compared to WIS16 and WKY16. In addition, WIS72 and WKY72 showed higher values than WIS16 and WKY16, respectively. Finally, no differences were observed in the strength rhythm analysis. CONCLUSIONS: SHR presented impaired thermoregulatory control at only 16 weeks of age when showing a higher body temperature during the activity phase, while other circadian rhythm parameters showed no differences across aging. Therefore, in taking our results as a whole we can conclude that WIS and WKY are appropriate Wistar strains to be used as normotensive controls for SHR.


Assuntos
Envelhecimento/fisiologia , Temperatura Corporal , Ritmo Circadiano/fisiologia , Hipertensão/fisiopatologia , Animais , Modelos Animais , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Ratos Wistar
5.
Pflugers Arch ; 472(12): 1757-1768, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33040159

RESUMO

This study aimed to evaluate the physical exercise-induced neuronal activation in brain nuclei controlling thermoregulatory responses in hypertensive and normotensive rats. Sixteen-week-old male normotensive Wistar rats (NWRs) and spontaneously hypertensive rats (SHRs) were implanted with an abdominal temperature sensor. After recovery, the animals were subjected to a constant-speed treadmill running (at 60% of the maximum aerobic speed) for 30 min at 25 °C. Core (Tcore) and tail-skin (Tskin) temperatures were measured every minute during exercise. Ninety minutes after the exercise, the rats were euthanized, and their brains were collected to determine the c-Fos protein expression in the following areas that modulate thermoregulatory responses: medial preoptic area (mPOA), paraventricular hypothalamic nucleus (PVN), and supraoptic nucleus (SON). During treadmill running, the SHR group exhibited a greater increase in Tcore and an augmented threshold for cutaneous heat loss relative to the NWR group. In addition, the SHRs showed reduced neuronal activation in the mPOA (< 49.7%) and PVN (< 44.2%), but not in the SON. The lower exercise-induced activation in the mPOA and PVN in hypertensive rats was strongly related to the delayed onset of cutaneous heat loss. We conclude that the enhanced exercise-induced hyperthermia in hypertensive rats can be partially explained by a delayed cutaneous heat loss, which is, in turn, associated with reduced activation of brain areas modulating thermoregulatory responses.


Assuntos
Regulação da Temperatura Corporal , Hipertensão/fisiopatologia , Hipotálamo/fisiopatologia , Corrida , Animais , Masculino , Ratos , Ratos Endogâmicos SHR , Ratos Wistar
6.
J Therm Biol ; 83: 30-36, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31331522

RESUMO

This study aimed to evaluate the changes in brain (Tbrain) and abdominal (Tabd) temperatures in spontaneously hypertensive rats (SHRs) following fatiguing exercise. Male normotensive Wistar rats (NWRs) and SHRs were used at 16 weeks of age. Their arterial pressure was measured by tail plethysmography prior to the experiments to confirm the hypertensive status of the SHRs. Then, the rats underwent implantation of an abdominal temperature sensor to measure Tabd and a guide cannula in the frontal cortex to enable the insertion of a thermistor to measure Tbrain. After a familiarization period, each animal was subjected to incremental speed exercises until fatigue in either a temperate (25 °C) or warm (32 °C) environment, followed by a 60-min post-exercise period at the same temperature at which they exercised. Tbrain, Tabd and tail-skin temperature (Tskin) were measured every min throughout the experiments. SHRs exhibited higher Tabd values than NWRs, and these higher values were transiently and persistently observed at 25 °C and 32 °C, respectively. For example, at 32 °C, Tabd was 0.84 °C higher in SHRs at the 25th min (large effect size). In contrast, regardless of the ambient temperature, SHRs exhibited similar Tbrain values as NWRs, indicating preserved Tbrain regulation following exercise in hypertensive rats. SHRs presented higher Tskin during the last half of the post-exercise period at 25 °C, whereas no inter-group differences were observed at 32 °C. In conclusion, the present results highlight that SHRs, an animal model that mimics uncontrolled essential hypertension in humans, exhibited greater impairments in regulating Tabd than Tbrain during the post-exercise period.


Assuntos
Abdome/fisiologia , Regulação da Temperatura Corporal , Córtex Cerebral/fisiologia , Hipertensão/fisiopatologia , Esforço Físico , Animais , Temperatura Corporal , Masculino , Ratos , Ratos Endogâmicos SHR , Ratos Wistar
7.
J Mol Cell Cardiol ; 90: 111-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26705058

RESUMO

We tested the effects of early mesenchymal stem cell (MSC) therapy associated with endurance exercise on the structural and functional cardiac remodeling of rats with myocardial infarctation (MI). Male Wistar rats (40 days old) were divided into 6 groups: control and exercise sham; control and exercise MI; and control and exercise MI MSC. MI was surgically induced and bone marrow-derived MSCs were immediately injected via caudal vein (concentration: 1 × 10(6 )cells). Twenty-four hours later ET groups exercised on a treadmill (5 days/week; 60 min/day; 60% of maximal running velocity) for 12 weeks. Structural and functional changes were determined by echocardiography. Contractility and intracellular global calcium ([Ca(2 +)]i) transient were measured in myocytes from the left ventricular (LV) non-infarcted area. Calcium regulatory proteins were measured by Western blot. MI increased (p < 0.05) heart, ventricular and LV weights and its ratios to body weight; LV internal dimension in diastole (LVID-D) and in systole (LVID-S) and LV free wall in diastole (LVFW-D), but reduced the thickness of interventricular septum in systole (IVS-S), ejection fraction (EF) and fractional shortening (FS). MI augmented (p < 0.05) the times to peak and to half relaxation of cell shortening as well as the amplitude of the [Ca(2 +)]i transient and the times to peak and to half decay. Early MSCs therapy restored LVFW-D, IVS-S and the amplitude and time to half decay of the [Ca(2 +)]i transient. Early endurance exercise intervention increased (p < 0.05) LVFW-S, IVS-S, EF and FS, and reduced the times to peak and to half relaxation of cell shortening, and the amplitude of the [Ca(2 +)]i transient. Exercise training also increased the expression of left ventricular SERCA2a and PLBser16. Nevertheless, the combination of these therapies did not cause additive effects. In conclusion, combining early MSCs therapy and endurance exercise does not potentiate the benefits of such treatments to structural and functional cardiac remodeling in infarcted rats.


Assuntos
Transplante de Células-Tronco Mesenquimais , Infarto do Miocárdio/terapia , Condicionamento Físico Animal , Animais , Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Diástole , Ecocardiografia , Expressão Gênica , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Contração Miocárdica/fisiologia , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Resistência Física , Ratos , Ratos Wistar , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Sístole , Remodelação Ventricular
8.
J Therm Biol ; 62(Pt A): 20-29, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27839546

RESUMO

The cardiovascular system plays a direct role in the maintenance of body temperature. Whether passive heating alters cardiovascular autonomic modulation in conscious rats is still unknown. This study investigated the effects of passive heating on systolic blood pressure variability (SBPV) and heart rate variability (HRV) in conscious rats and the involvement of the renin-angiotensin system in the passive heating effects on SBPV and HRV. Fourteen male Wistar rats were randomly assigned to the control group or the losartan treatment group. A catheter was implanted in the left carotid artery to record pulsatile arterial pressure (PAP), and a telemetry sensor was implanted in the abdominal cavity to measure body temperature (Tbody). After recovering from surgery, the animals were subjected to a passive heating protocol (35°C; 30min) in resting conditions, during which Tbody, tail skin temperature and PAP were measured. The mean arterial pressure, systolic and diastolic blood pressure, heart rate, double product (i.e., the product of systolic blood pressure by heart rate), SBPV and HRV were calculated from the PAP. SBPV and HRV were analyzed in terms of both time and frequency domains. Increases in the thermoregulatory and cardiovascular parameters were observed during passive heating in both groups, and those increases were reflected in the higher time and frequency domains of the SBPV. However, passive heating was not effective in altering HRV. Passive heating altered SBPV but not HRV in conscious rats when they were treated with losartan.


Assuntos
Pressão Sanguínea , Regulação da Temperatura Corporal , Frequência Cardíaca , Animais , Pressão Arterial , Sistema Nervoso Autônomo/fisiologia , Temperatura Corporal , Temperatura Alta , Masculino , Ratos , Ratos Wistar , Sistema Renina-Angiotensina , Processamento de Sinais Assistido por Computador , Termografia/métodos
9.
J Sports Sci Med ; 13(3): 695-701, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25177201

RESUMO

The control of body temperature in Spontaneously Hypertensive Rat (SHR) subjected to exercise in warm environment was investigated. Male SHR and Wistar rats were submitted to moderate exercise in temperate (25°C) and warm (32°C) environments while body and tail skin temperatures, as well as oxygen consumption, were registered. Total time of exercise, workload performed, mechanical efficiency and heat storage were determined. SHR had increased heat production and body temperature at the end of exercise, reduced mechanical efficiency and increased heat storage (p < 0.05). Furthermore, these rats also showed a more intense and faster increase in body temperature during moderate exercise in the warm environment (p < 0.05). The lower mechanical efficiency seen in SHR was closely correlated with their higher body temperature at the point of fatigue in warm environment (p < 0.05). Our results indicate that SHR exhibit significant differences in body temperature control during moderate exercise in warm environment characterized by increased heat production and heat storage during moderate exercise in warm environment. The combination of these responses result in aggravated hyperthermia linked with lower mechanical efficiency. Key PointsThe practice of physical exercise in warm environment has gained importance in recent decades mainly because of the progressive increases in environmental temperature;To the best of our knowledge, these is the first study to analyze body temperature control of SHR during moderate exercise in warm environment;SHR showed increased heat production and heat storage that resulted in higher body temperature at the end of exercise;SHR showed reduced mechanical efficiency;These results demonstrate that when exercising in a warm environment the hypertensive rat exhibit differences in temperature control.

10.
J Mol Cell Cardiol ; 57: 119-28, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23376037

RESUMO

The aim of the present study was to verify the effects of low-intensity endurance training and detraining on the mechanical and molecular properties of cardiomyocytes from spontaneously hypertensive rats (SHRs). Male SHRs and normotensive control Wistar rats at 16-weeks of age were randomly divided into eight groups of eight animals: NC8 and HC8 (normotensive and hypertensive control for 8weeks); NT8 and HT8 (normotensive and hypertensive trained at 50-60% of maximal exercise capacity for 8weeks); NC12 and HC12 (normotensive and hypertensive control for 12weeks); NDT and HDT (normotensive and hypertensive trained for 8weeks and detrained for 4weeks). The total exercise time until fatigue (TTF) was determined by a maximal exercise capacity test. Resting heart rate (RHR) and systolic arterial pressure (SAP) were measured. After the treatments, animals were killed by cervical dislocation and left ventricular myocytes were isolated by enzymatic dispersion. Isolated cells were used to determine intracellular global Ca(2+) ([Ca(2+)]i) transient and cardiomyocyte contractility (1Hz; ~25°C). [Ca(2+)]i regulatory proteins were measured by Western blot, and the markers of pathologic cardiac hypertrophy by quantitative real-time polymerase chain reaction (q-RT-PCR). Exercise training augmented the TTF (NC8, 11.4±1.5min vs. NT8, 22.5±1.4min; HC8, 11.7±1.4min vs. HT8, 24.5±1.3min; P<0.05), reduced RHR (NT8initial, 340±8bpm vs. NT8final, 322±10bpm; HT8initial, 369±8bpm vs. HT8final, 344±10bpm; P<0.05), and SBP in SHR animals (HC8, 178±3mmHg vs. HT8, 161±4mmHg; P<0.05). HC8 rats showed a slower [Ca(2+)]i transient (Tpeak, 83.7±1.8ms vs. 71.7±2.4ms; T50%decay, 284.0±4.3ms vs. 264.0±4.1ms; P<0.05) and cell contractility (Vshortening, 86.1±6.7µm/s vs. 118.6±6.7µm/s; Vrelengthening, 57.5±7.4µm/s vs. 101.3±7.4µm/s; P<0.05), and higher expression of ANF (300%; P<0.05), skeletal α-actin (250%; P<0.05) and a decreased α/ß-MHC ratio (70%; P<0.05) compared to NC8. Exercise training increased [Ca(2+)]i transient (NC8, 2.39±0.06F/F0 vs. NT8, 2.72±0.06F/F0; HC8, 2.28±0.05F/F0 vs. HT8, 2.82±0.05F/F0; P<0.05), and cell contractility (NC8, 7.4±0.3% vs. NT8, 8.4±0.3%; HC8, 6.8±0.3% vs. HT8, 7.8±0.3%; P<0.05). Furthermore, exercise normalized the expression of ANF, skeletal α-actin, and the α/ß-MHC ratio in HT8 rats, augmented the expression of SERCA2a (NC8, 0.93±0.15 vs. NT8, 1.49±0.14; HC8, 0.83±0.13 vs. HT8, 1.32±0.14; P<0.05) and PLBser16 (NC8, 0.89±0.18 vs. NT8, 1.23±0.17; HC8, 0.77±0.17 vs. HT8, 1.32±0.16; P<0.05), and reduced PLBt/SERCA2a (NC8, 1.21±0.19 vs. NT8, 0.50±0.21; HC8, 1.38±0.17 vs. HT8, 0.66±0.21; P<0.05). However, all these adaptations returned to control values within 4weeks of detraining in both SHR and normotensive control animals. In conclusion, low-intensity endurance training induces positive benefits to left ventricular myocyte mechanical and molecular properties, which are reversed within 4weeks of detraining.


Assuntos
Hipertensão/terapia , Contração Miocárdica , Miócitos Cardíacos/fisiologia , Animais , Fator Natriurético Atrial/genética , Fator Natriurético Atrial/metabolismo , Sinalização do Cálcio , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Células Cultivadas , Terapia por Exercício , Expressão Gênica , Ventrículos do Coração/metabolismo , Ventrículos do Coração/fisiopatologia , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Hipertrofia Ventricular Esquerda/metabolismo , Hipertrofia Ventricular Esquerda/patologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Cadeias Pesadas de Miosina/metabolismo , Condicionamento Físico Animal , Resistência Física , Ratos , Ratos Endogâmicos SHR , Ratos Wistar , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo
11.
BMJ Case Rep ; 16(1)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609420

RESUMO

Herein we present a case of severe alkalaemia (pH 7.81) due to suspected acute-on-chronic respiratory alkalosis in a patient with chronic anxiety and metabolic alkalosis secondary to emesis. The patient was managed in the intensive care unit with significant improvement and discharged in stable condition. The case report emphasises considering a broad differential of aetiologies that can cause acid-base status derangements and identifying the appropriate therapeutic approach.


Assuntos
Alcalose Respiratória , Alcalose , Humanos , Alcalose Respiratória/etiologia , Alcalose/etiologia , Alcalose/terapia , Equilíbrio Ácido-Base , Concentração de Íons de Hidrogênio
12.
J Med Eng Technol ; 47(8): 389-395, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38780358

RESUMO

Climate change has amplified the importance of continuous and precise body core temperature (Tcore) monitoring in the everyday life. In this context, assessing Tcore through ingestible capsules technology, i.e., gastrointestinal temperature (Tgastrointestinal), emerges as a good alternative to prevent heat-related illness. Therefore, we conducted a systematic review to point out values of normal Tgastrointestinal measured through ingestible capsules in healthy humans. The study followed PRISMA guidelines and searched the PubMed and Scielo databases from 1971 to 2023. Our search strategy included the descriptors ("gastrointestinal temperature") AND ("measurement"), and eligible studies had to be written in English and measured Tgastrointestinal using ingestible capsules or sensors in healthy adults aged 18-59 at rest. Two pairs of researchers independently reviewed titles and abstracts and identified 35 relevant articles out of 1,088 in the initial search. An average value of 37.13 °C with a standard deviation of 0.24 °C was observed, independently of the gender. The values measured ranged from 36.70 °C to 37.69 °C. In conclusion, this systematic review pointed out the mean value of 37.13 ± 0.24 °C measured by ingestible capsules as reference for resting Tgastrointestinal in healthy adult individuals.


Assuntos
Temperatura Corporal , Trato Gastrointestinal , Humanos , Temperatura Corporal/fisiologia , Trato Gastrointestinal/fisiologia , Cápsulas , Adulto
13.
Clin Exp Pharmacol Physiol ; 39(2): 155-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22288490

RESUMO

Hypertension leads to electrophysiological changes in the heart. Chronic exercise induced by a treadmill-running programme (TRP) is considered a potential non-pharmacological treatment for hypertension and may have implications in heart remodelling. However, it is not known whether the TRP is able to improve the electrophysiological properties of the heart in spontaneously hypertensive rats (SHR). In the present study, we investigated whether TRP affects the electrical properties of left ventricular (LV) myocytes isolated from different layers of the LV wall of SHR. Male SHR were divided into exercised (chronic treadmill running for 8 weeks; CEX-SHR) and sedentary (SED-SHR) groups. Age-matched normotensive Wistar male rats served as controls. Action potentials (AP) and transient outward potassium current (I(to) ) were recorded in subepicardial (EPI) and subendocardial (ENDO) LV myocytes. In normotensive controls, AP duration (APD) was longer in ENDO cells than in EPI cells. This sort of transmural heterogeneity in the LV was not observed in sedentary SHR and was partially restored in SHR subject to chronic exercise. This partial recovery was associated with an increase in I(to) density in EPI cells but not in ENDO cells. The electrophysiological changes observed in the CEX-SHR group were not accompanied by either amelioration of systolic blood pressure or a reduction in heart hypertrophy. These findings imply that a TRP is able to improve the electrophysiological parameters of isolated cardiac myocytes in SHR. This sort of adaptation contributes to the overall improvement of heart physiology in this model.


Assuntos
Potenciais de Ação , Hipertensão/fisiopatologia , Hipertensão/terapia , Miócitos Cardíacos/fisiologia , Condicionamento Físico Animal , Função Ventricular Esquerda , Animais , Ventrículos do Coração/citologia , Masculino , Contração Miocárdica , Ratos , Ratos Endogâmicos SHR , Ratos Wistar
14.
Cureus ; 14(6): e25593, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35785005

RESUMO

Crowned dens syndrome (CDS) is a clinical entity characterized by neck pain associated with fever, headaches, and neck stiffness, along with radiologic evidence of peri-odontoid process calcification in a characteristic "crown" or "halo" distribution. It is likely an underdiagnosed condition and patients can initially be misdiagnosed, leading to costly evaluation and unnecessary treatment interventions. We present the case of a 76-year-old man who presented to the emergency department (ED) with a 3-day history of progressively worsening neck pain that was associated with headaches, malaise, decreased oral intake, chills, and fever. Initial evaluation was significant for the presence of fever, tachycardia, and elevated inflammatory markers. We report a case of CDS attributed to calcium pyrophosphate deposition and review the pertinent literature about the presentation, diagnostic evaluation, and treatment of this rare clinical entity.

15.
Cureus ; 14(2): e21801, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35261828

RESUMO

Lung herniation is an uncommon clinical entity characterized by protrusion of pulmonary tissue through an area of weakness in the chest wall. We present the case of a 56-year-old man with a history of chronic obstructive pulmonary disease (COPD) and crack-cocaine use who presented to the emergency department due to left-sided lateral chest pain, as well as a two-week history of cough, shortness of breath, and wheezing. Chest imaging revealed a contusion on the left flank and intercostal widening with a left-sided pulmonary herniation between ribs 8 and 9. Cardiothoracic surgery was consulted for assessment of pulmonary herniation and recommended conservative management. His pain was managed with multimodal analgesia and the patient was deemed stable for discharge. At outpatient follow-up two weeks later, his pain was well-controlled. To our knowledge, this is the first reported case of pulmonary herniation in which crack cocaine use is implicated as a contributing cause. The outcome achieved in our case supports the use of conservative management with analgesia as a valid strategy for select patients with lung herniation.

16.
J Biomol Struct Dyn ; 40(20): 9620-9635, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34060428

RESUMO

Bothrops atrox venom comprises several types of bioactive molecules, enzymatic and non-enzymatic, among those, Batroxrhagin is the most predominant SVMP P-III enzyme, which are responsible for induction of local and systemic hemorrhage and muscle fibers damage, impairing regeneration. Due to great difficulties in establishing an antibothropic drug, new strategies must be addressed to achieve a more effective and efficient treatment. There are no studies of specific catalytic inhibitors of Batroxrhagin. However, there are in vitro studies that have described similar metalloprotease inhibitors. The inhibitor batimastat was used as a leading compound for the search and selection of similar candidates. This molecule is widely cited as a metalloprotease inhibitor and as an antimetastatic. In addition to batimastat-like molecules, four other reported metalloprotease inhibitors were included to compose the study's positive control group. Hence, 580 molecules were tested. The three-dimensional structure of B. atrox Batroxrhagin was predicted based on homologous structures using Modeller 9.20. Molecular docking calculation was performed using Autodock 4.2 and molecular surfaces and interactions were analyzed using Biovia/Discovery Studio 2017. Among 576 molecules, 42 similar to batismast resulted in a better energy of interaction than all positive controls, including batimastat itself. The batimastat-like molecules with lowest energy and positive controls were subjected to molecular dynamics for 30 ns in Gromacs 2019.4. This batimastat-like molecule produced better stability among all the Batroxrhagin-ligand complexes analyzed. Overall, the proposed compounds present justifiable evidence for future in vitro tests aiming to inhibit Batroxrhagin. Communicated by Ramaswamy H. Sarma.


Assuntos
Bothrops , Venenos de Crotalídeos , Animais , Simulação de Acoplamento Molecular , Metaloproteases
17.
BMJ Case Rep ; 14(6)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34187798

RESUMO

Lemierre syndrome (LS) is an acute oropharyngeal infection with secondary septic thrombophlebitis and distant septic embolisation. A 29-year-old woman with sore throat, dyspnoea and left shoulder pain, who was on levofloxacin for 3 days, presented with worsening symptoms. She was tachycardic, tachypneic and hypoxic on presentation. CT of neck and chest revealed multiple loculated abscesses on her left lower neck and shoulder, right peritonsillar abscess, thrombosis of the right external jugular vein and multiple bilateral septic emboli to the lungs. She was started on clindamycin and ampicillin sulbactam for LS. She developed septic shock and required intubation due to respiratory failure. Drainage of the left shoulder abscess grew Fusobacterium nucleatum After 2 weeks of a complicated intensive care unit stay, her haemodynamic status improved and she was transferred to the floor. LS has variable presentations, but regardless of the presentation, it is a potentially fatal disease-requiring prompt diagnosis and management.


Assuntos
Infecções por Fusobacterium , Síndrome de Lemierre , Abscesso Peritonsilar , Faringite , Tromboflebite , Adulto , Feminino , Infecções por Fusobacterium/diagnóstico , Infecções por Fusobacterium/tratamento farmacológico , Fusobacterium necrophorum , Fusobacterium nucleatum , Humanos , Veias Jugulares/diagnóstico por imagem , Síndrome de Lemierre/diagnóstico , Síndrome de Lemierre/tratamento farmacológico , Tromboflebite/diagnóstico por imagem , Tromboflebite/tratamento farmacológico
18.
Life (Basel) ; 11(8)2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34440530

RESUMO

BACKGROUND: The effects of swimming training associated with insulin treatment on the cortical bone health in young rats with severe type 1 diabetes remain unclear, although there is evidence of such effects on the cancellous bone. This study examined the effects of swimming training combined with insulin therapy on the femoral midshaft structural and mechanical properties in growing rats with type 1 diabetes. METHODS: Male Wistar rats were divided into six groups (n = 10): control sedentary, control exercise, diabetic sedentary, diabetic exercise, diabetic sedentary plus insulin and diabetic exercise plus insulin. Diabetic rats received an injection (60 mg/kg body weight) of streptozotocin (STZ). Exercised animals underwent a swimming program for eight weeks. RESULTS: Diabetes induced by STZ decreased the bone mineral content (BMC) and density (BMD), and cortical thickness and maximum load and tenacity in the femoral midshaft. Insulin treatment partially counteracted the damages induced by diabetes on BMC, BMD and cortical thickness and tenacity. Swimming training did not affect the femoral structural and mechanical properties in diabetic rats. The combination of treatments did not potentiate the insulin effects. In conclusion, swimming training does not affect the benefits of insulin treatment on the femoral midshaft structural and mechanical properties in growing rats with severe type 1 diabetes.

19.
Am J Physiol Heart Circ Physiol ; 298(6): H2039-45, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20304817

RESUMO

Thiamine is an important cofactor of metabolic enzymes, and its deficiency leads to cardiovascular dysfunction. First, we characterized the metabolic status measuring resting oxygen consumption rate and lactate blood concentration after 35 days of thiamine deficiency (TD). The results pointed to a decrease in resting oxygen consumption and a twofold increase in blood lactate. Confocal microscopy showed that intracellular superoxide (approximately 40%) and H(2)O(2) (2.5 times) contents had been increased. In addition, biochemical activities and protein expression of SOD, glutathione peroxidase, and catalase were evaluated in hearts isolated from rats submitted to thiamine deprivation. No difference in SOD activity was detected, but protein levels were found to be increased. Catalase activity increased 2.1 times in TD hearts. The observed gain in activity was attended by an increased catalase protein level. However, a marked decrease in glutathione peroxidase activity (control 435.3 + or - 28.6 vs. TD 199.4 + or - 30.2 nmol NADPH x min(-1) x ml(-1)) was paralleled by a diminution in the protein levels. Compared with control hearts, we did observe a greater proportion of apoptotic myocytes by TdT-mediated dUTP nick end labeling (TUNEL) and caspase-3 reactivity techniques. These results indicate that during TD, reactive oxygen species (ROS) production may be enhanced as a consequence of the installed acidosis. The perturbation in the cardiac myocytes redox balance was responsible for the increase in apoptosis.


Assuntos
Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Coração/fisiopatologia , Estresse Oxidativo/fisiologia , Deficiência de Tiamina/complicações , Animais , Apoptose/fisiologia , Catalase/metabolismo , Modelos Animais de Doenças , Glutationa Peroxidase/metabolismo , Lactatos/sangue , Masculino , Miocárdio/metabolismo , Miocárdio/patologia , Consumo de Oxigênio/fisiologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
20.
J Sports Med Phys Fitness ; 60(5): 800-805, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32141278

RESUMO

BACKGROUND: The aim of the present study was to investigate the exercise capacity of hypertensive rats at different stages of development of hypertension and to determine the most suitable index to evaluate the exercise capacity in different strains. METHODS: Male spontaneously hypertensive rat (SHR) and normotensive Wistar rats (NWR) of 5, 8, 12 and 16 weeks were submitted to the exercise capacity test. The exercise running time was measured and the workload was calculated. RESULTS: Normotensive and hypertensive rats when assess the exercise capacity by exercise running time exhibited a reduction in exercise performance over time. Moreover, hypertensive rats showed lower exercise capacity compared to normotensive control when analyzed by workload. CONCLUSIONS: The present results indicate that hypertensive rats exhibit reduced exercise capacity compared to normotensive rats regardless of age assessed. Beside that, in experiments with strains with different body mass the most reliable index to assess exercise capacity is workload.


Assuntos
Tolerância ao Exercício/fisiologia , Condicionamento Físico Animal/métodos , Esforço Físico/fisiologia , Animais , Hipertensão/fisiopatologia , Masculino , Ratos , Ratos Endogâmicos SHR , Ratos Wistar
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