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1.
J Therm Biol ; 119: 103781, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38232473

RESUMEN

Ice slurry ingestion during prolonged exercises may improve performance in hot environments; however, the ideal amount and timing of ingestion are still uncertain. We determined whether ad libitum ice slurry ingestion influences physiological and perceptual variables and half-marathon performance while comparing the effects of the amount and moment of ingestion between ice slurry and water at 37 °C. Ten trained participants (28 ± 2 years; mean and SD) were required to run two half marathons while consuming either ice slurry (-1 °C; Ad-1) or water (37 °C; 37 CE) ad libitum. They then performed two other half marathons where, during one, they were required to ingest an amount of water equivalent to the amount consumed during the Ad-1 trial (Pro37), and in the other, to ingest ice slurry in the amount consumed during the 37 CE trial (Pro-1). During the half marathons, dry-bulb temperature and relative humidity were controlled at 33.1 ± 0.3 °C and 60 ± 3%, respectively. Ad-1 ingestion (349.6 ± 58.5 g) was 45% less than 37 CE ingestion (635.5 ± 135.8 g). Physical performance, heart rate, perceived exertion, body temperatures, and thermal perception were not influenced by the temperature or amount of beverage ingestion. However, a secondary analysis suggested that lower beverage ingestion was associated with improved performance (Ad-1 + Pro37 vs. 37 CE + Pro-1: -4.0 min, Cohen's d = 0.39), with a significant relationship between lower beverage ingestion and faster running time (b = 0.02, t = 4.01, p < 0.001). In conclusion, ice slurry ingestion does not affect performance or physiological or perceptual variables during a half marathon in a hot environment. Preliminary evidence suggests that lower beverage ingestion (ice slurry or warm water) is associated with improved performance compared to higher ingestion.


Asunto(s)
Temperatura Corporal , Agua , Humanos , Temperatura Corporal/fisiología , Regulación de la Temperatura Corporal/fisiología , Hielo , Carrera de Maratón , Calor , Ingestión de Alimentos
2.
Exp Physiol ; 108(6): 852-864, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37018484

RESUMEN

NEW FINDINGS: What is the central question of this study? The aim was to identify the factors predicting the body core temperature of athletes at the end of a 10 km self-paced run in a hot environment. What is the main finding and its importance? Hyperthermia in athletes subjected to self-paced running depends on several factors, highlighting the integrated control of core temperature during exercise under environmental heat stress. Five of the seven variables that significantly predicted core temperature are not invasive and, therefore, practical for use outside the laboratory environment: heart rate, sweat rate, wet-bulb globe temperature, running speed and maximal oxygen consumption. ABSTRACT: Measurement of body core temperature (Tcore ) is paramount to determining the thermoregulatory strain of athletes. However, standard measurement procedures of Tcore are not practical for extended use outside the laboratory environment. Therefore, determining the factors that predict Tcore during a self-paced run is crucial for creating more effective strategies to minimize the heat-induced impairment of endurance performance and reduce the occurrence of exertional heatstroke. The aim of this study was to identify the factors predicting Tcore values attained at the end of a 10 km time trial (end-Tcore ) under environmental heat stress. Initially, we extracted data obtained from 75 recordings of recreationally trained men and women. Next, we ran hierarchical multiple linear regression analyses to understand the predictive power of the following variables: wet-bulb globe temperature, average running speed, initial Tcore , body mass, differences between Tcore and skin temperature (Tskin ), sweat rate, maximal oxygen uptake, heart rate and change in body mass. Our data indicated that Tcore increased continuously during exercise, attaining 39.6 ± 0.5°C (mean ± SD) after 53.9 ± 7.5 min of treadmill running. This end-Tcore value was primarily predicted by heart rate, sweat rate, differences between Tcore and Tskin , wet-bulb globe temperature, initial Tcore , running speed and maximal oxygen uptake, in this order of importance (ß power values corresponded to 0.462, -0.395, 0.393, 0.327, 0.277, 0.244 and 0.228, respectively). In conclusion, several factors predict Tcore in athletes subjected to self-paced running under environmental heat stress. Moreover, considering the conditions investigated, heart rate and sweat rate, two practical (non-invasive) variables, have the highest predictive power.


Asunto(s)
Trastornos de Estrés por Calor , Carrera , Masculino , Humanos , Femenino , Temperatura Corporal/fisiología , Temperatura , Calor , Regulación de la Temperatura Corporal/fisiología , Carrera/fisiología , Respuesta al Choque Térmico/fisiología , Oxígeno
3.
Brain Sci ; 12(11)2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36358408

RESUMEN

BACKGROUND: Rathke's cleft cysts (RCC) arise from the pars intermedia because of incomplete regression of the embryologic Rathke pouch. A subset of RCC becomes symptomatic causing headaches, visual and endocrinological disturbances such that surgical intervention is indicated. Several points in surgical management remain controversial including operative strategy (simple fenestration (SF) vs complete cyst wall resection (CWR)) as well as reconstructive techniques. METHODS: A retrospective analysis was conducted of pathologically confirmed RCC operated on by endoscopic endonasal approach from 2006 to 2019. Pre-operative symptoms, imaging characteristics, operative strategy, symptom response, complications and recurrences were recorded. RESULTS: Thirty-nine patients were identified. Thirty-three underwent SF and six underwent CWR. Worsening pituitary function was significantly increased with CWR (50%) compared to SF (3%) (p = 0.008). All patients underwent "closed" reconstruction with a post-operative CSF leak rate of 5% (3% SF vs 16% CWR, p = 0.287). Six (15%) recurrences necessitating surgery were reported. Recurrence rates stratified by surgical technique (18% SF vs 0% CWR, p = 0.564) were not found to be significantly different. CONCLUSIONS: The current series illustrates variability in the surgical management of RCCs. SF with closed reconstruction is a reasonable operative strategy for most symptomatic RCCs cases while CWR can be reserved for selected cases.

4.
World Neurosurg ; 161: e625-e634, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35217229

RESUMEN

BACKGROUND: Sellar arachnoid cysts (SACs) are rare lesions that require treatment only if symptomatic. The endoscopic endonasal approach has been widely used. Despite their simple cystic appearance and the straight-forward surgical intervention, important associated risks exist, with cerebrospinal fluid (CSF) leak the prevalent risk. METHODS: A retrospective analysis of patients with pathologically confirmed SAC between January 2006 and December 2019 was conducted. A homogeneous simple cyst-opening technique and skull base reconstruction with nasoseptal flaps was used. RESULTS: A total of 10 patients were identified (7 women and 3 men; median age, 54.5 years; range, 20-77 years). Of the 10 patients, 8 had had newly diagnosed SACs and 2 patients had had recurrence from a previously microsurgically fenestrated SAC. Eight patients had presented with visual symptoms, one with visual symptoms and fatigue, and one with intractable headaches. Neuro-ophthalmological and endocrinological assessments had revealed visual field deficits in 6, visual acuity decline in 5, and hypopituitarism in 2 patients. The median calculated volume was 1.71 mL (range, 0.27-2.54 mL). Postoperatively, no CSF leak and no further surgical complications were noted. The visual field had improved in 4 of 6 patients and visual acuity had improved in 4 of 5 patients. Anterior pituitary function had improved in 1, worsened in 1, and remained stable in 8 patients. One patient had developed diabetes insipidus. One recurrence was recorded at 54 months postoperatively. CONCLUSIONS: The results from the present study have shown that SACs can be effectively treated using a simple cyst-opening technique. The routine use of nasoseptal flaps significantly reduced the risk of CSF leakage without compromising nasal quality of life in the long term or mandating additional incisions. Long-term follow-up is important to monitor for late recurrence.


Asunto(s)
Quistes Aracnoideos , Quistes Aracnoideos/diagnóstico por imagen , Quistes Aracnoideos/cirugía , Pérdida de Líquido Cefalorraquídeo/etiología , Pérdida de Líquido Cefalorraquídeo/cirugía , Endoscopía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Estudios Retrospectivos
5.
Clinics (Sao Paulo) ; 76: e2142, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33503182

RESUMEN

OBJECTIVE: This study aimed to assess miRNA-195 expression in the tumor tissues from a cohort of Brazilian female breast cancer patients undergoing neoadjuvant chemotherapy (NAC) and evaluate its correlation with various clinicopathological markers. METHODS: Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to evaluate the miRNA-195 expression in tumor tissues from a cohort of female breast cancer patients undergoing NAC. This expression was then correlated with the occurrence of several distinct breast cancer molecular subtypes and other clinicopathological variables. RESULTS: A total of 55 patients were included in this study, 28 (50.9%) of whom were treated using NAC. Tumor miRNA-195 expression was suppressed in breast cancer patients, regardless of their exposure to systemic treatments, histological grade, size, nodal status, and tumor-node-metastasis (TNM) staging. This was more pronounced in luminal and triple-negative patients, and patient's response to NAC was correlated with an increase in miRNA-195 expression. CONCLUSION: miRNA-195 is downregulated in the tumor tissues of Brazilian breast cancer patients regardless of NAC exposure; this reinforces its role as a tumor suppressor and a potential biomarker for chemotherapy response.


Asunto(s)
Neoplasias de la Mama , MicroARNs , Protocolos de Quimioterapia Combinada Antineoplásica , Biomarcadores de Tumor/genética , Brasil , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Femenino , Humanos , MicroARNs/genética , Terapia Neoadyuvante , Estadificación de Neoplasias , Pronóstico
6.
Clinics ; 76: e2142, 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1153983

RESUMEN

OBJECTIVE: This study aimed to assess miRNA-195 expression in the tumor tissues from a cohort of Brazilian female breast cancer patients undergoing neoadjuvant chemotherapy (NAC) and evaluate its correlation with various clinicopathological markers. METHODS: Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to evaluate the miRNA-195 expression in tumor tissues from a cohort of female breast cancer patients undergoing NAC. This expression was then correlated with the occurrence of several distinct breast cancer molecular subtypes and other clinicopathological variables. RESULTS: A total of 55 patients were included in this study, 28 (50.9%) of whom were treated using NAC. Tumor miRNA-195 expression was suppressed in breast cancer patients, regardless of their exposure to systemic treatments, histological grade, size, nodal status, and tumor-node-metastasis (TNM) staging. This was more pronounced in luminal and triple-negative patients, and patient's response to NAC was correlated with an increase in miRNA-195 expression. CONCLUSION: miRNA-195 is downregulated in the tumor tissues of Brazilian breast cancer patients regardless of NAC exposure; this reinforces its role as a tumor suppressor and a potential biomarker for chemotherapy response.


Asunto(s)
Humanos , Femenino , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Neoplasias de la Mama/tratamiento farmacológico , MicroARNs/genética , Pronóstico , Brasil , Protocolos de Quimioterapia Combinada Antineoplásica , Biomarcadores de Tumor/genética , Terapia Neoadyuvante , Estadificación de Neoplasias
7.
Artículo en Inglés | MEDLINE | ID: mdl-33116816

RESUMEN

INTRODUCTION: MicroRNA-21 (miRNA-21) has been described as one of the most significantly upregulated miRNAs in human breast cancer. However, limited knowledge exists on miRNA-21 expression in breast cancer tissue after neoadjuvant chemotherapy (NAC). PURPOSE: The aim of this study was to assess miRNA-21 expression in the tumor tissues of Brazilian patients with breast cancer who underwent NAC and its correlation with clinicopathological variables. PATIENTS AND METHODS: Utilizing qRT-PCR, miRNA-21 expression in tumor tissue was measured in a cohort of female patients with breast cancer who underwent NAC. The correlation of miRNA-21 expression with breast cancer molecular subtypes and other clinicopathological variables was also assessed. RESULTS: A total of 55 patients were included in the study, and 28 (50.9%) underwent NAC. miRNA-21 was upregulated in patients with breast cancer, regardless of previous exposure to chemotherapy, molecular subtypes, tumor-node-metastasis (TNM) staging and lymph node status of the axilla. miRNA-21 expression did not differ between patients with breast cancer who achieved a pathologic complete response after NAC and healthy controls. CONCLUSION: miRNA-21 was upregulated in the tumor tissue of Brazilian patients with breast cancer regardless of NAC treatment, which reinforces its role as an "oncomiR" and a potential biomarker.

8.
Ecol Evol ; 10(13): 6364-6372, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32724518

RESUMEN

Nutrients are known to limit productivity of plant communities around the world. In the Brazilian Cerrado, indirect evidences point to phosphorus as the main limiting nutrient, but some fertilization experiments suggest that one or more micronutrients might play this role. Boron is one of the essential micronutrients for plants. Agronomically, it received some attention, but it has mostly been neglected in ecological studies assessing the effects of nutrients on plant growth. Through field fertilization and mesocosm experiments in a degraded area in the Cerrado, we show that boron addition increased biomass production of herbaceous vegetation. This could be related to a lower aluminum uptake in the boron fertilized plants. Even considering that plant growth was promoted by boron addition due to aluminum toxicity alleviation, this is the first study reporting boron limitation in natural, noncultivated plant communities and also the first report of this kind in vegetative grasses. These results contribute to disentangling patterns of nutrient limitation among plant species of the species-rich, aluminum-rich, and nutrient-poor Cerrado biome and highlight the potential role of micronutrients, such as boron, for growth of noncrop plants. Understanding how nutrient limitation differs among functional groups in the highly biodiverse areas founded on ancient tropical soils may help managing these plant communities in a changing world.

9.
Acta Neurochir (Wien) ; 159(2): 281-290, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27999953

RESUMEN

BACKGROUND: Peripheral nerve injury is a common and important cause of morbidity and disability in patients who have suffered a traumatic injury, particularly younger people. Various different injuries can result in damage to specific nerves. In patients with multiple trauma, the prevalence of peripheral nerve injury is estimated at 2.8%, but can reach 5% with the inclusion of brachial plexus involvement. Physical examination, as well as the origin and location of the trauma, can indicate the nerve involved and the type of nerve damage. However, the depth and severity of damage, and the structures involved often cannot be determined initially, but depend on longer periods of observation to reach a definitive and accurate diagnosis for which treatment can be proposed. Current approaches to locate and assess the severity of traumatic nerve injury involve clinical and electrodiagnostic studies. From a clinical and neurophysiological point of view, nerve injuries are classified in an attempt to correlate the degree of injury with symptoms, type of pathology, and prognosis, as well as to determine the therapy to be adopted. OBJECTIVES: MRI in the diagnosis of traumatic peripheral nerve injury has increasingly been used by surgeons in clinical practice. In this article, we analyze the use of magnetic resonance (MR) for the evaluation of traumatic peripheral nerve diseases that are surgically treatable. We also consider basic concepts in the evaluation of technical and MR signs of peripheral nerve injuries. MATERIALS AND METHODS: Studies were identified following a computerized search of MEDLINE (1950 to present), EMBASE (1980 to present), and the Cochrane database. The MEDLINE search was conducted on PUBMED, the EMBASE search was conducted on OVID, and the Cochrane database was conducted using their online library. A set was created using the terms: 'traumatic', 'nerve', and 'resonance'. RESULTS: The included articles were identified using a computerized search and the resulting databases were then sorted according to the inclusion and exclusion criteria. This yielded 10,340 articles (MEDLINE, n = 758; EMBASE, n = 9564; and Cochrane, n = 18). A search strategy was then built by excluding articles that only concern plexus injury and adding the terms 'neuropathies', 'DTI' and 'neurotmesis'. In total, seven studies were included in the review effectively addressing the role of MRI in the evaluation of traumatic peripheral nerve injury. We extracted all relevant information on the imaging findings and the use of magnetic resonance in trauma. We did not include technical or specific radiological aspects of the imaging techniques. CONCLUSIONS: These seven articles were subsequently evaluated by analyzing their results, methodological approach, and conclusions presented.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Traumatismos de los Nervios Periféricos/diagnóstico por imagen , Humanos
10.
Odontol. mod ; 20(2): 21-4, mar.-abr. 1993. tab
Artículo en Portugués | BBO - Odontología | ID: biblio-852631

RESUMEN

Devido à grande variedade de modelos de esterilização de limas endodônticas e à falta de padronização da preferida técnica, propusemos a pesquisa da eficiência de pastilhas de formol como agente esterilizante. Foram utilizados recepientes metálicos, hermeticamente fechados, com volumes aproximados da caixa endodôntica (1000 cm) e quatro pastilhas de formol envolvidos em gaze. Utilizou-se bochecho com soro fisiológico para a contaminação das limas, representando bactérias de microbiota oral. Em cada caixa foram colocadas três limas contaminadas, dispostas em um suporte apropriado. Aos intervalos de tempo de 20, 40 e 60 minutos as limas foram retiradas e colocadas em caldo de tioglicolato e incubadas a 37ºC por 48 horas. Ao término do tempo de incubação verificou-se a presença ou não do crescimento bacteriano, pela turvação do meio. As limas que ficaram em contato com o formol por 40 e 60 minutos não apresentaram crescimento, indicando ser capaz de eliminar os microorganismos contaminantes


Asunto(s)
Endodoncia/instrumentación , Esterilización/instrumentación
11.
Rev. Assoc. Paul. Cir. Dent ; 44(5): 271-3, set.-out. 1990. ilus
Artículo en Portugués | LILACS, BBO - Odontología | ID: biblio-855469

RESUMEN

Os autores apresentam um caso de deslocamento do 3º molar inferior para o espaço sub-mandibular durante tentativa de extração. A falta de planejamento adequado, associado às manobras intempestivas, parece ter sido a causa de tal deslocamento


Asunto(s)
Humanos , Masculino , Adulto , Tercer Molar/cirugía , Extracción Dental , Diente Impactado/cirugía
12.
Rev. Assoc. Paul. Cir. Dent ; 42(3): 220-1, maio-jun. 1988. ilus
Artículo en Portugués | LILACS, BBO - Odontología | ID: lil-80504

RESUMEN

Os autores descrevem um caso de localizaçäo rara de terceiro molar inferior, situado na regiäo amigdaliana direita. Säo apresentadas e discutidas as prováveis causas do deslocamento do dente para a referida posiçäo ectópica. Os autores frente a ausência de manobras cirúrgicas intempesticas prévias e de patologias associadas, aceitam a hipótese do deslocamento primário da papila formadora do órgäo do esmalte para a regiäo amigdaliana. Resaltam também a importância do exame clínico e radiográfico para que um diangóstico correto possa ser firmado e terapêutica adequada instituída


Asunto(s)
Adulto , Humanos , Masculino , Diente Molar , Diente Impactado , Diente Impactado
13.
RGO (Porto Alegre) ; 34(5): 386-93, set.-out. 1986. ilus
Artículo en Portugués | LILACS, BBO - Odontología | ID: biblio-854415

RESUMEN

Com a finalidade de estudar as alterações sofridas por dente conservado em glicerina a 98//e transplantado homogeneamente, 72 dentes foram obtidos de ratos albinos (Rattus norvegicus albinus, Wistar); conservados em glicerina a 98//por no mínimo 30 dias, e transplantado homogeneamente a outros 72 ratos da mesma linhagem, que foram divididos em três grupos de acordo com os procedimentos realizados nos dentes. Esses ratos foram sacrificados em grupos de quatro aos 5, 10, 20, 30, 60 e 90 dias pós-operatórios. As peças obtidas foram preparadas, efetuados cortes semi-seriados, corados pela hematoxilina-eosina, através da seqüência laboratorial de rotina. Através dessas lâminas foi realizado estudo histológico que nos permitiu as seguintes conclusões: a) a glicerina a 98//mostrou-se viável para a estocagem de dentes; b) o hidróxido de cálcio não se mostrou um material adequado para o preenchimento de cavidade pulpar de dente de crescimento contínuo com ampla abertura apical para transplantação em alvéolos imediatamente após a extração; c) em comparação com os demais grupos, no grupo de dentes que foi realizado o esvaziamento pulpar, foram menos pronunciadas a invasão do epitélio gengival para o FUNDUS alveolar, a reabsorção cemento dentinária e a anquilose alvéolo dental; d) a reabsorção cemento dentinária foi mais pronunciada no grupo de dentes com preenchimento da cavidade pulpar com pasta a base de hidróxido de cálcio


Asunto(s)
Animales , Ratas , Diente/trasplante , Trasplante Homólogo
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