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1.
Nat Commun ; 11(1): 6378, 2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-33311503

RESUMO

Homeotherms maintain a stable internal body temperature despite changing environments. During energy deficiency, some species can cease to defend their body temperature and enter a hypothermic and hypometabolic state known as torpor. Recent advances have revealed the medial preoptic area (MPA) as a key site for the regulation of torpor in mice. The MPA is estrogen-sensitive and estrogens also have potent effects on both temperature and metabolism. Here, we demonstrate that estrogen-sensitive neurons in the MPA can coordinate hypothermia and hypometabolism in mice. Selectively activating estrogen-sensitive MPA neurons was sufficient to drive a coordinated depression of metabolic rate and body temperature similar to torpor, as measured by body temperature, physical activity, indirect calorimetry, heart rate, and brain activity. Inducing torpor with a prolonged fast revealed larger and more variable calcium transients from estrogen-sensitive MPA neurons during bouts of hypothermia. Finally, whereas selective ablation of estrogen-sensitive MPA neurons demonstrated that these neurons are required for the full expression of fasting-induced torpor in both female and male mice, their effects on thermoregulation and torpor bout initiation exhibit differences across sex. Together, these findings suggest a role for estrogen-sensitive MPA neurons in directing the thermoregulatory and metabolic responses to energy deficiency.


Assuntos
Temperatura Corporal/fisiologia , Estrogênios/metabolismo , Neurônios/fisiologia , Área Pré-Óptica/metabolismo , Torpor/fisiologia , Animais , Temperatura Corporal/genética , Regulação da Temperatura Corporal/fisiologia , Metabolismo Energético/fisiologia , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Jejum , Feminino , Hipotermia/genética , Hipotermia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
2.
J Med Eng Technol ; 44(8): 468-471, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32990119

RESUMO

COVID-19 pandemics required a reorganisation of social spaces to prevent the spread of the virus. Due to the common presence of fever in the symptomatic patients, temperature measurement is one of the most common screening protocols. Indeed, regulations in many countries require temperature measurements before entering shops, workplaces, and public buildings. Due to the necessity of providing rapid non-contact and non-invasive protocols to measure body temperature, infra-red thermometry is mostly used. Many countries are now facing the need to organise the return to school and universities in the COVID-19 era, which require solutions to prevent the risk of contagion between students and/or teachers and technical/administrative staff. This paper highlights and discusses some of the strengths and limitations of infra-red cameras, including the site of measurements and the influence of the environment, and recommends to be careful to consider such measurements as a single "safety rule" for a good return to normality.


Assuntos
Temperatura Corporal/fisiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Instituições Acadêmicas , Betacoronavirus , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/fisiopatologia , Febre/diagnóstico , Humanos , Raios Infravermelhos , Pneumonia Viral/diagnóstico , Pneumonia Viral/fisiopatologia , Termografia
3.
Proc Natl Acad Sci U S A ; 117(36): 22357-22366, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32839313

RESUMO

Fever is a conserved and prominent response to infection. Yet, the issue of how CD4 T cell responses are modulated if they occur at fever temperatures remains poorly addressed. We have examined the priming of naive CD4 T cells in vitro at fever temperatures, and we report notable fever-mediated modulation of their cytokine commitment. When naive CD4 T cells were primed by plate-bound anti-CD3 and anti-CD28 monoclonal antibodies at moderate fever temperature (39 °C), they enhanced commitment to IL4/5/13 (Th2) and away from IFNg (Th1). This was accompanied by up-regulation of the Th2-relevant transcription factor GATA3 and reduction in the Th1-relevant transcription factor Tbet. Fever sensing by CD4 T cells involved transient receptor potential vanilloid cation channels (TRPVs) since TRPV1/TRPV4 antagonism blocked the febrile Th2 switch, while TRPV1 agonists mediated a Th2 switch at 37 °C. The febrile Th2 switch was IL4 independent, but a γ-secretase inhibitor abrogated it, and it was not found in Notch1-null CD4 T cells, identifying the Notch pathway as a major mediator. However, when naive CD4 T cells were primed via antigen and dendritic cells (DCs) at fever temperatures, the Th2 switch was abrogated via increased production of IL12 from DCs at fever temperatures. Thus, immune cells directly sense fever temperatures with likely complex physiological consequences.


Assuntos
Linfócitos T CD4-Positivos/fisiologia , Diferenciação Celular/fisiologia , Febre/fisiopatologia , Receptores Notch/metabolismo , Canais de Cátion TRPV/metabolismo , Animais , Temperatura Corporal/fisiologia , Linfócitos T CD4-Positivos/citologia , Células Cultivadas , Temperatura Alta , Camundongos , Modelos Biológicos
4.
Am J Physiol Regul Integr Comp Physiol ; 319(4): R455-R465, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32783688

RESUMO

Hibernators suppress physiological processes when expressing torpor, yet little is known about the effects of torpor on male reproductive physiology. Studies of hibernating mammals suggest that deep torpor negatively impacts spermatogenesis and that transitions between torpor and euthermic arousals increase cellular oxidative stress, with potentially damaging effects on sperm. Here, we hypothesize that variation in torpor expression affects the reproductive readiness of hibernators by impacting their sperm production. To test this, we examined the relationship between torpor expression and spermatogenesis in captive eastern chipmunks (Tamias striatus). We determined torpor depth with temperature data loggers and assessed its relationship with spermatogenesis by examining spermatogenic progression, cell division, sperm counts, sperm maturity, and DNA damage. We show that deep hibernators (high levels of torpor) largely halted spermatogenesis in late hibernation in comparison with shallow hibernators (low levels of torpor), where ongoing spermatogenesis was observed. Despite these differences in spermatogenic state during hibernation, spermatogenic progression, sperm numbers, and maturity did not differ in spring, potentially reflecting similar degrees of reproductive readiness. Interestingly, shallow hibernators exhibited higher rates of DNA damage in spermatogenic cells during hibernation, with this trend reversing in spring. Our results thus indicate that once heterothermy is terminated, deep hibernators resume spermatogenesis but are characterized by higher rates of DNA damage in spermatogenic cells at the seasonal stage when spring mating commences. Therefore, our study confirmed posthibernation recovery of sperm production but also a potential impact of deep torpor expression during winter on DNA damage in spring.


Assuntos
Temperatura Corporal/fisiologia , Hibernação/fisiologia , Sciuridae/fisiologia , Espermatogênese/fisiologia , Torpor/fisiologia , Animais , Dano ao DNA/fisiologia , Metabolismo Energético/fisiologia , Masculino , Contagem de Espermatozoides , Temperatura
5.
Nature ; 583(7816): 421-424, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32641825

RESUMO

The suprachiasmatic nucleus (SCN) serves as the body's master circadian clock that adaptively coordinates changes in physiology and behaviour in anticipation of changing requirements throughout the 24-h day-night cycle1-4. For example, the SCN opposes overnight adipsia by driving water intake before sleep5,6, and by driving the secretion of anti-diuretic hormone7,8 and lowering body temperature9,10 to reduce water loss during sleep11. These responses can also be driven by central osmo-sodium sensors to oppose an unscheduled rise in osmolality during the active phase12-16. However, it is unknown whether osmo-sodium sensors require clock-output networks to drive homeostatic responses. Here we show that a systemic salt injection (hypertonic saline) given at Zeitgeber time 19-a time at which SCNVP (vasopressin) neurons are inactive-excited SCNVP neurons and decreased non-shivering thermogenesis (NST) and body temperature. The effects of hypertonic saline on NST and body temperature were prevented by chemogenetic inhibition of SCNVP neurons and mimicked by optogenetic stimulation of SCNVP neurons in vivo. Combined anatomical and electrophysiological experiments revealed that osmo-sodium-sensing organum vasculosum lamina terminalis (OVLT) neurons expressing glutamic acid decarboxylase (OVLTGAD) relay this information to SCNVP neurons via an excitatory effect of γ-aminobutyric acid (GABA). Optogenetic activation of OVLTGAD neuron axon terminals excited SCNVP neurons in vitro and mimicked the effects of hypertonic saline on NST and body temperature in vivo. Furthermore, chemogenetic inhibition of OVLTGAD neurons blunted the effects of systemic hypertonic saline on NST and body temperature. Finally, we show that hypertonic saline significantly phase-advanced the circadian locomotor activity onset of mice. This effect was mimicked by optogenetic activation of the OVLTGAD→ SCNVP pathway and was prevented by chemogenetic inhibition of OVLTGAD neurons. Collectively, our findings provide demonstration that clock time can be regulated by non-photic physiologically relevant cues, and that such cues can drive unscheduled homeostatic responses via clock-output networks.


Assuntos
Relógios Circadianos/fisiologia , Vias Neurais , Neurônios/metabolismo , Sódio/metabolismo , Núcleo Supraquiasmático/fisiologia , Ácido gama-Aminobutírico/metabolismo , Animais , Temperatura Corporal/efeitos dos fármacos , Temperatura Corporal/fisiologia , Relógios Circadianos/efeitos dos fármacos , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Ingestão de Líquidos/efeitos dos fármacos , Glutamato Descarboxilase/metabolismo , Locomoção/efeitos dos fármacos , Locomoção/fisiologia , Masculino , Camundongos , Vias Neurais/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Optogenética , Organum Vasculosum/citologia , Organum Vasculosum/efeitos dos fármacos , Organum Vasculosum/enzimologia , Organum Vasculosum/fisiologia , Concentração Osmolar , Solução Salina Hipertônica/administração & dosagem , Solução Salina Hipertônica/metabolismo , Solução Salina Hipertônica/farmacologia , Sódio/administração & dosagem , Sódio/farmacologia , Núcleo Supraquiasmático/citologia , Núcleo Supraquiasmático/efeitos dos fármacos , Vasopressinas/metabolismo
6.
J Am Med Dir Assoc ; 21(7): 895-899.e1, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32674815

RESUMO

OBJECTIVES: Many nursing home residents infected with SARS-CoV-2 fail to be identified with standard screening for the associated COVID-19 syndrome. Current nursing home COVID-19 screening guidance includes assessment for fever, defined as a temperature of at least 38.0°C. The objective of this study was to describe the temperature changes before and after universal testing for SARS-CoV-2 in nursing home residents. DESIGN: Cohort study. SETTING AND PARTICIPANTS: The Veterans Administration (VA) operates 134 Community Living Centers (CLC), similar to nursing homes, that house residents who cannot live independently. VA guidance to CLCs directed daily clinical screening for COVID-19 that included temperature assessment. MEASURES: All CLC residents (n = 7325) underwent SARS-CoV-2 testing. We report the temperature in the window of 14 days before and after universal SARS-CoV-2 testing among CLC residents. Baseline temperature was calculated for 5 days before the study window. RESULTS: SARS-CoV-2 was identified in 443 (6.0%) residents. The average maximum temperature in SARS-CoV-2-positive residents was 37.66 (0.69) compared with 37.11 (0.36) (P = .001) in SARS-CoV-2-negative residents. Temperatures in those with SARS-CoV-2 began rising 7 days before testing and remained elevated during the 14-day follow-up. Among SARS-CoV-2-positive residents, only 26.6% (n = 118) met the fever threshold of 38.0°C during the survey period. Most residents (62.5%, n = 277) with confirmed SARS-CoV-2 did experience 2 or more 0.5°C elevations above their baseline values. One cohort of SARS-CoV-2 residents' (20.3%, n = 90) temperatures never deviated >0.5°C from baseline. CONCLUSIONS AND IMPLICATIONS: A single screening for temperature is unlikely to detect nursing home residents with SARS-CoV-2. Repeated temperature measurement with a patient-derived baseline can increase sensitivity. The current fever threshold as a screening criteria for SARS-CoV-2 infection should be reconsidered.


Assuntos
Infecções por Coronavirus/diagnóstico , Febre/diagnóstico , Programas de Rastreamento/métodos , Casas de Saúde/organização & administração , Pneumonia Viral/diagnóstico , Instituições de Cuidados Especializados de Enfermagem/organização & administração , Idoso , Idoso de 80 Anos ou mais , Temperatura Corporal/fisiologia , Técnicas de Laboratório Clínico/métodos , Estudos de Coortes , Infecções por Coronavirus/prevenção & controle , Surtos de Doenças/prevenção & controle , Diagnóstico Precoce , Feminino , Febre/epidemiologia , Humanos , Controle de Infecções , Masculino , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Termômetros/estatística & dados numéricos , Estados Unidos , Veteranos
7.
Sci Rep ; 10(1): 9485, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32528038

RESUMO

Time-of-day dependent fluctuations in exercise performance have been documented across different sports and seem to affect both endurance and resistance modes of exercise. Most of the studies published to date have shown that the performance in short-duration maximal exercises (i.e. less than 1 min - e.g. sprints, jumps, isometric contractions) exhibits diurnal fluctuations, peaking between 16:00 and 20:00 h. However, the time-of-day effects on short duration exercise performance may be minimized by the following factors: (1) short exposures to moderately warm and humid environments; (2) active warm-up protocols; (3) intermittent fasting conditions; (4) warming-up while listening to music; or (5) prolonged periods of training at a specific time of day. This suggests that short-duration maximal exercise performance throughout the day is controlled not only by body temperature, hormone levels, motivation and mood state but also by a versatile circadian system within skeletal muscle. The time of day at which short-duration maximal exercise is conducted represents an important variable for training prescription. However, the literature available to date lacks a specific review on this subject. Therefore, the present review aims to (1) elucidate time-of-day specific effects on short-duration maximal exercise performance and (2) discuss strategies to promote better performance in short-duration maximal exercises at different times of the day.


Assuntos
Desempenho Atlético/fisiologia , Exercício Físico/fisiologia , Temperatura Corporal/fisiologia , Humanos , Motivação/fisiologia , Músculo Esquelético/fisiologia , Resistência Física/fisiologia , Fatores de Tempo
8.
Scand J Trauma Resusc Emerg Med ; 28(1): 50, 2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32493456

RESUMO

BACKGROUND: Mobile intensive care units frequently manage unplanned out-of-hospital births (UOHB). Rewarming methods during pre-hospital management of UOHB have not yet been compared. The aim was to compare rewarming methods used during pre-hospital management in a large prospective cohort of UOHB in France. METHODS: We analysed UOHB from the prospective AIE cohort from 25 prehospital emergency medical services in France. The primary outcome was the change in body temperature from arrival at scene to arrival at hospital. RESULTS: From 2011 to 2018, 1854 UOHB were recorded, of whom 520 were analysed. We found that using incubator care was the most effective rewarming method (+ 0.8 °C during transport), followed by the combination of plastic bag, skin-to-skin and cap (+ 0.2 °C). The associations plastic bag + cap and skin-to-skin + cap did not allow the newborn to be warmed up but rather to maintain initial temperature (+ 0.0 °C). The results of the multivariate model were consistent with these observations, with better rewarming with the use of an incubator. We also identified circumstances of increased risk of hypothermia according to classification and regression tree, like premature birth (< 37 weeks of gestation) and/or low outside temperature (< 8.4 °C). CONCLUSIONS: Using an incubator was the most effective rewarming method during pre-hospital management of UOHB in our French prospective cohort. Based on our model, in cases of term less than 37 weeks of gestation or between 37 and 40 weeks with a low outside temperature or initial hypothermia, using such a method would be preferred.


Assuntos
Temperatura Baixa/efeitos adversos , Hipotermia/terapia , Reaquecimento/métodos , Temperatura Corporal/fisiologia , Serviços Médicos de Emergência/métodos , Feminino , França/epidemiologia , Humanos , Hipotermia/epidemiologia , Recém-Nascido , Masculino , Gravidez , Estudos Prospectivos
9.
Proc Natl Acad Sci U S A ; 117(26): 14636-14641, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32541064

RESUMO

Understanding the coordination of cell-division timing is one of the outstanding questions in the field of developmental biology. One active control parameter of the cell-cycle duration is temperature, as it can accelerate or decelerate the rate of biochemical reactions. However, controlled experiments at the cellular scale are challenging, due to the limited availability of biocompatible temperature sensors, as well as the lack of practical methods to systematically control local temperatures and cellular dynamics. Here, we demonstrate a method to probe and control the cell-division timing in Caenorhabditis elegans embryos using a combination of local laser heating and nanoscale thermometry. Local infrared laser illumination produces a temperature gradient across the embryo, which is precisely measured by in vivo nanoscale thermometry using quantum defects in nanodiamonds. These techniques enable selective, controlled acceleration of the cell divisions, even enabling an inversion of division order at the two-cell stage. Our data suggest that the cell-cycle timing asynchrony of the early embryonic development in C. elegans is determined independently by individual cells rather than via cell-to-cell communication. Our method can be used to control the development of multicellular organisms and to provide insights into the regulation of cell-division timings as a consequence of local perturbations.


Assuntos
Temperatura Corporal/fisiologia , Divisão Celular/fisiologia , Desenvolvimento Embrionário/fisiologia , Pontos Quânticos/química , Termometria , Animais , Caenorhabditis elegans/embriologia , Nanodiamantes/química , Termometria/instrumentação , Termometria/métodos
10.
Eur J Endocrinol ; 183(3): 343-355, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32508310

RESUMO

Objective: Retrospective studies suggest that women have more active brown adipose tissue (BAT) than men, but little is known of the effect of fluctuating sex steroids across the menstrual cycle on thermogenesis in women. Design: To characterise the effects of sex and sex steroids on BAT activity we recruited healthy weight men (n = 14) and women at two stages of the menstrual cycle (luteal, n = 9; follicular, n = 11). Methods: Infrared thermography measured supraclavicular temperature to index BAT thermogenesis in response to both cold (immersion of one hand in water at 15°C) and meal (Ensure, 10 kcal/kg body weight) stimuli. Results: Adaptive BAT temperature responses were greater (P < 0.05) in women than men, irrespective of stage of menstrual cycle. Whereas during cold exposure, the increase in BAT temperature was abrogated (P < 0.05) in women during follicular phase compared to men and women during luteal phase. Plasma concentrations of progesterone, 17ß-estradiol, testosterone and cortisol were measured. Regression analyses demonstrated that baseline BAT temperature was positively correlated (P < 0.05) with progesterone levels, but was inversely associated (P < 0.05) with cortisol concentration. Both cold- and meal-induced changes in BAT temperature mildly correlated (P = 0.07; P < 0.05) with 17ß-estradiol levels, but not with testosterone concentrations. Conclusions: Baseline supraclavicular temperature is elevated in women during the luteal phase of the menstrual cycle, which correlated with elevated progesterone concentrations. Women exhibited greater thermogenic responses than men, irrespective of the state of the menstrual cycle, which was associated with plasma levels of 17ß-estradiol. We conclude that sex steroids may regulate BAT thermogenesis in healthy adults.


Assuntos
Tecido Adiposo Marrom/fisiologia , Hormônios Esteroides Gonadais/fisiologia , Caracteres Sexuais , Termogênese/fisiologia , Adulto , Temperatura Corporal/fisiologia , Temperatura Baixa , Estradiol/sangue , Feminino , Fase Folicular/fisiologia , Humanos , Fase Luteal/fisiologia , Masculino , Refeições , Ciclo Menstrual/fisiologia , Estudos Retrospectivos , Testosterona/sangue , Adulto Jovem
11.
Emerg Med Australas ; 32(5): 867-869, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32578926

RESUMO

OBJECTIVE: To report the incidence of fever among patients who tested positive for SARS-CoV-2. METHODS: Retrospective cohort study of patients who tested positive for SARS-CoV-2 at a single centre. Temperature at time of testing and on repeat testing within 24 h were collected. RESULTS: At the time of testing, fever was detected (sensitivity) in 16 of 86 (19%; 95% confidence interval 11-28) episodes of positive tests for SARS-CoV-2. With repeat testing, fever was detected in 18 of 75 (24%; 95% confidence interval 15-35) episodes. CONCLUSIONS: In an Australian hospital, screening for fever lacked sensitivity for detection of patients with SARS-CoV-2.


Assuntos
Infecções por Coronavirus/prevenção & controle , Febre/diagnóstico , Programas de Rastreamento/métodos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Austrália , Temperatura Corporal/fisiologia , Estudos de Coortes , Intervalos de Confiança , Infecções por Coronavirus/epidemiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Febre/epidemiologia , Humanos , Incidência , Masculino , Pandemias/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Estudos Retrospectivos , Medição de Risco , Sensibilidade e Especificidade , Centros de Atenção Terciária
12.
Phys Ther Sport ; 44: 47-52, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32416581

RESUMO

OBJECTIVES: To determine normal temperatures over the Patella tendon over eleven weeks. DESIGN: A prospective cohort study with eleven weeks of observation. SETTING: University's Human Biomechanics and Physiology Laboratory. PARTICIPANTS: Male or female collegiate runners running at least 25 miles per week who did not report pain in the region of the Patella tendon over 11 weeks of data collection. MAIN OUTCOME MEASURES: Thermal images taken at the same time and day of the week, were used to measure the temperature of the skin over the Patella tendon. RESULTS: Eighteen athletes were eligible for analysis. The mean temperature of the Patella tendon was 30.13 °C (SD = 1.51 °C). Patella tendon temperature changes over time were insignificant (right p = 0.66, left p = 0.90) with ICC right = 0.92, left = 0.94. Mean temperature difference side to side was 0.14 °C (SD = 0.60 °C). Mixed-model Linear regression for mean temperature differences found the effect of (i) time (t = 0.39, p = 0.70, df = 361) and (ii) side (t = -0.89, p = 0.38, df = 361) to be insignificant. CONCLUSIONS: This is the first report of normal thermal profiles of collegiate runners over an extended period. Temperature variation above 1.20 °C may represent an abnormal asymmetry in the running population. Variations in Patella tendon temperatures left to right, and over time were not significant.


Assuntos
Atletas , Temperatura Corporal/fisiologia , Ligamento Patelar/fisiologia , Estações do Ano , Universidades , Adulto , Feminino , Seguimentos , Humanos , Masculino , Estudos Prospectivos , Termografia/métodos , Adulto Jovem
13.
J Dairy Sci ; 103(8): 6751-6770, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32448584

RESUMO

Animal welfare can be negatively affected when dairy cattle experience heat stress. Managing heat stress has become more of a challenge than ever before, due to the increasing number of production animals with increased milk yield, and therefore greater metabolic activity. Environmental temperatures have increased by 1.0°C since the 1800s and are expected to continue to increase by another 1.5°C between 2030 and 2052. Heat stress affects production, reproduction, nutrition, health, and welfare. Means exist to monitor and evaluate heat stress in dairy cattle, as well as different ways to abate heat, all with varying levels of effectiveness. This paper is a summary and compilation of information on dairy cattle heat stress over the years.


Assuntos
Bovinos/fisiologia , Resposta ao Choque Térmico , Animais , Temperatura Corporal/fisiologia , Bovinos/psicologia , Indústria de Laticínios , Feminino , Lactação/fisiologia , Masculino , Leite
14.
Sensors (Basel) ; 20(10)2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32438729

RESUMO

Many types of thermometers have been developed to measure body temperature. Infrared thermometers (IRT) are fast, convenient and ease to use. Two types of infrared thermometers are uses to measure body temperature: tympanic and forehead. With the spread of COVID-19 coronavirus, forehead temperature measurement is used widely to screen people for the illness. The performance of this type of device and the criteria for screening are worth studying. This study evaluated the performance of two types of tympanic infrared thermometers and an industrial infrared thermometer. The results showed that these infrared thermometers provide good precision. A fixed offset between tympanic and forehead temperature were found. The measurement values for wrist temperature show significant offsets with the tympanic temperature and cannot be used to screen fevers. The standard operating procedure (SOP) for the measurement of body temperature using an infrared thermometer was proposed. The suggestion threshold for the forehead temperature is 36 °C for screening of fever. The body temperature of a person who is possibly ill is then measured using a tympanic infrared thermometer for the purpose of a double check.


Assuntos
Temperatura Corporal/fisiologia , Infecções por Coronavirus/diagnóstico , Febre/diagnóstico , Pneumonia Viral/diagnóstico , Termômetros , Infecções por Coronavirus/fisiopatologia , Infecções por Coronavirus/virologia , Febre/fisiopatologia , Febre/virologia , Testa/fisiopatologia , Humanos , Raios Infravermelhos , Pandemias , Pneumonia Viral/fisiopatologia , Pneumonia Viral/virologia
15.
Clinics (Sao Paulo) ; 75: e1639, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32321115

RESUMO

OBJECTIVES: The enhanced recovery after surgery (ERAS) protocol recommends prevention of intraoperative hypothermia. However, the beneficial effect of maintaining normothermia after radical cystectomy has not been evaluated. This study aimed to investigate the efficacy of fluid warming nursing in elderly patients undergoing Da Vinci robotic-assisted laparoscopic radical cystectomy. METHODS: A total of 108 patients with bladder cancer scheduled to undergo DaVinci robotic-assisted laparoscopic radical cystectomy were recruited and randomly divided into the control group (n=55), which received a warming blanket (43°C) during the intraoperative period and the warming group (n=53), in which all intraoperative fluids were administered via a fluid warmer (41°C). The surgical data, body temperature, coagulation function indexes, and postoperative complications were compared between the two groups. RESULTS: Compared to the control group, the warming group had significantly less intraoperative transfusion (p=0.028) and shorter hospitalization days (p<0.05). During the entire intraoperative period (from 1 to 6h), body temperature was significantly higher in the warming group than in the control group. There were significant differences in preoperative fibrinogen level, white blood cell count, total bilirubin level, intraoperative lactose level, postoperative thrombin time (TT), and platelet count between the control and warming groups. Multivariate linear regression analysis demonstrated that TT was the only significant factor, suggesting that the warming group had a lower TT than the control group. CONCLUSION: Fluid warming nursing can effectively reduce transfusion requirement and hospitalization days, maintain intraoperative normothermia, and promote postoperative coagulation function in elderly patients undergoing Da Vinci robotic-assisted laparoscopic radical cystectomy.


Assuntos
Temperatura Corporal/fisiologia , Cistectomia/métodos , Cuidados Intraoperatórios/métodos , Complicações Intraoperatórias/prevenção & controle , Laparoscopia , Procedimentos Cirúrgicos Robóticos/métodos , Neoplasias da Bexiga Urinária/cirurgia , Idoso , Feminino , Humanos , Período Intraoperatório , Masculino , Complicações Pós-Operatórias/prevenção & controle , Tremor por Sensação de Frio/fisiologia , Neoplasias da Bexiga Urinária/patologia
16.
J Dairy Sci ; 103(6): 5440-5454, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32253038

RESUMO

Producers in the western United States commonly use spray water at the feed bunk and fans in the lying area to mitigate heat stress in dairy cows. Often, spray water cycles on and off with fans turning on when a preset air temperature is reached. Although this method can be effective, innovative strategies are needed to reduce water and energy use. We evaluated the effectiveness and resource efficiency of 4 cooling treatments on behavioral and physiological responses in dairy cows housed in a freestall barn: (1) conductive cooling in which mats with recirculating evaporatively cooled water were buried under sand bedding (Mat; activated at 18.9°C); (2) targeted convective cooling in which evaporatively cooled air was directed toward the cows through fabric ducts with nozzles at both the feed bunk and lying areas (Targeted Air; activated at 22°C); (3) evaporative cooling, with spray water in the feed area and fan over the freestalls (Baseline; activated at 22°C); and (4) evaporative cooling with half the amount of spray water used in the Baseline and the fan moved to the feed bunk (Optimized Baseline; activated at 22°C). In a crossover design, 8 groups of cows (4/group) producing an average (± standard deviation) of 37.5 ± 4.5 kg/d of milk were tested for 3 d per treatment. For ethical reasons, beginning at 30°C, the Mat treatment was supplemented with Baseline cooling and the Targeted Air treatment had spray water at the Optimized Baseline rate. We recorded body temperature, posture, and location within the pen every 3 min for 24 h/d, and respiration rates every 30 min daily from 1000 to 1900 h. Daily air temperature averaged (±SD) 26.3 ± 7.1°C during 24 h and 33.3 ± 4°C from 1000 to 1900 h. We used pairwise comparisons of each treatment to Baseline to evaluate response variables. Milk production did not differ across treatments, nor did time spent lying (51 ± 2%/d on average). Respiration rates did not differ across treatments overall (61 ± 3 breaths/min), but on an hourly basis, cows in the Mat treatment had a significantly higher rate than those in Baseline, at h 10 and 11 (70 vs. 58-59 breaths/min). Body temperature averaged 38.7 ± 0.05°C across treatments and was 0.2 to 0.3°C higher in the Mat treatment than in Baseline at h 10, 11, 20, 21, and 22. These results collectively indicate that the Mat treatment did not effectively reduce indicators of heat load compared with Baseline. In contrast, Targeted Air and Optimized Baseline were both effective but differed in aspects of efficiency. Targeted Air used the least amount of water but the most energy of all options tested. In conclusion, more efficient heat abatement options were identified, particularly an Optimized Baseline strategy, which cut water use in half, required the same amount of energy as the Baseline, and maintained similar physiological and behavioral responses in cows.


Assuntos
Temperatura Corporal , Temperatura Baixa , Indústria de Laticínios/métodos , Transtornos de Estresse por Calor/veterinária , Animais , Roupas de Cama, Mesa e Banho , Temperatura Corporal/fisiologia , Bovinos , Feminino , Transtornos de Estresse por Calor/prevenção & controle , Lactação , Leite , Taxa Respiratória , Água
17.
Anesth Analg ; 130(5): 1167-1175, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32287124

RESUMO

BACKGROUND: Reimbursement for anesthesia services has been shifting from a fee-for-service model to a value-based model that ties payment to quality metrics. The Centers for Medicare & Medicaid Service's (CMS) value-based payment program includes a quality measure for perioperative temperature management (Measure #424, Perioperative Temperature Management). Compliance may impose new challenges in clinical practice, data collection, and reporting. We investigated the impact of an electronic decision-support tool on adherence to this emerging standard. METHODS: In this retrospective observational study, perioperative temperature data were collected from cases eligible for reporting this measure to CMS from a single academic medical center before and after the implementation of an electronic decision-support tool that prompted temperature measurement and maintenance of normothermia. Proportions of measure compliance were assessed using segmented regression analysis. Proportions of intraoperative temperature measurement were also assessed, and multivariable logistic regression was performed to assess the association between patient and surgical factors and measure compliance. RESULTS: A total of 24,755 cases eligible for reporting in 2017 were assessed, and 25,274 cases from 2016 were included as an extended baseline. Segmented time-series regression did not show a significant baseline trend in measure compliance. Introduction of the alerts was associated with an increase in overall compliance from 84.4% (95% confidence interval [CI], 83.6%-85.2%) to 92.4% (91.4%-93.4%), and an increase in intraoperative compliance from 26.8% (25.8%-27.8%) to 71.0% (69.6%-72.4%). The association between the alerts and overall compliance was also present on multivariable analysis. CONCLUSIONS: Implementation of an intraoperative decision-support tool was associated with statistically significant improvement in the maintenance of normothermia in cases eligible for reporting to CMS. This led to improved compliance with Measure #424 and suggests that electronic alerts can help practices improve their performance and payment bonus eligibility.


Assuntos
Temperatura Corporal/fisiologia , Monitorização Intraoperatória/normas , Assistência Perioperatória/normas , Guias de Prática Clínica como Assunto/normas , Qualidade da Assistência à Saúde/normas , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/instrumentação , Assistência Perioperatória/instrumentação , Estudos Retrospectivos
18.
AJNR Am J Neuroradiol ; 41(4): 555-565, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32139425

RESUMO

The remarkable temperature sensitivity of the brain is widely recognized and has been studied for its role in the potentiation of ischemic and other neurologic injuries. Pyrexia frequently complicates large-vessel acute ischemic stroke and develops commonly in critically ill neurologic patients; the profound sensitivity of the brain even to minor intraischemic temperature changes, together with the discovery of brain-to-systemic as well as intracerebral temperature gradients, has thus compelled the exploration of cerebral thermoregulation and uncovered its immutable dependence on cerebral blood flow. A lack of pragmatic and noninvasive tools for spatially and temporally resolved brain thermometry has historically restricted empiric study of cerebral temperature homeostasis; however, MR thermometry (MRT) leveraging temperature-sensitive nuclear magnetic resonance phenomena is well-suited to bridging this long-standing gap. This review aims to introduce the reader to the following: 1) fundamental aspects of cerebral thermoregulation, 2) the physical basis of noninvasive MRT, and 3) the physiologic interdependence of cerebral temperature, perfusion, metabolism, and viability.


Assuntos
Regulação da Temperatura Corporal/fisiologia , Encéfalo/fisiologia , Imagem por Ressonância Magnética/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Termometria/métodos , Temperatura Corporal/fisiologia , Circulação Cerebrovascular/fisiologia , Transtornos Cerebrovasculares/diagnóstico por imagem , Transtornos Cerebrovasculares/fisiopatologia , Feminino , Hemodinâmica/fisiologia , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Acidente Vascular Cerebral/fisiopatologia
19.
Pediatrics ; 145(4)2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32193210

RESUMO

OBJECTIVES: Reduce postoperative hypothermia by up to 50% over a 12-month period in children's hospital NICUs and identify specific clinical practices that impact success. METHODS: Literature review, expert opinion, and benchmarking were used to develop clinical practice recommendations for maintaining perioperative euthermia that included the following: established euthermia before transport to the operating room (OR), standardized practice for maintaining euthermia on transport to and from the OR, and standardized practice to prevent intraoperative heat loss. Process measures were focused on maintaining euthermia during these time points. The outcome measure was the proportion of patients with postoperative hypothermia (temperature ≤36°C within 30 minutes of a return to the NICU or at the completion of a procedure in the NICU). Balancing measures were the proportion of patients with postoperative temperature >38°C or the presence of thermal burns. Multivariable logistic regression was used to identify key practices that improved outcome. RESULTS: Postoperative hypothermia decreased by 48%, from a baseline of 20.3% (January 2011 to September 2013) to 10.5% by June 2015. Strategies associated with decreased hypothermia include >90% compliance with patient euthermia (36.1-37.9°C) at times of OR arrival (odds ratio: 0.58; 95% confidence interval [CI]: 0.43-0.79; P < .001) and OR departure (odds ratio: 0.0.73; 95% CI: 0.56-0.95; P = .017) and prewarming the OR ambient temperature to >74°F (odds ratio: 0.78; 95% CI: 0.62-0.999; P = .05). Hyperthermia increased from a baseline of 1.1% to 2.2% during the project. No thermal burns were reported. CONCLUSIONS: Reducing postoperative hypothermia is possible. Key practices include prewarming the OR and compliance with strategies to maintain euthermia at select time points throughout the perioperative period.


Assuntos
Hipotermia/prevenção & controle , Assistência Perioperatória/métodos , Complicações Pós-Operatórias/prevenção & controle , Benchmarking , Temperatura Corporal/fisiologia , Regulação da Temperatura Corporal/fisiologia , Queimaduras/epidemiologia , Humanos , Hipotermia/epidemiologia , Lactente , Unidades de Terapia Intensiva Neonatal , Modelos Logísticos , Razão de Chances , Salas Cirúrgicas , Avaliação de Resultados em Cuidados de Saúde , Período Perioperatório , Complicações Pós-Operatórias/epidemiologia , Desenvolvimento de Programas , Fatores de Tempo , Transporte de Pacientes
20.
Acta Diabetol ; 57(8): 959-963, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32144491

RESUMO

AIMS: Cardiac autonomic modulation, as assessed by heart rate variability (HRV), is independently attenuated by both type 1 diabetes (T1D) and exercise-heat stress, although their combined effects remain unclear. We therefore assessed HRV during exercise-heat stress in young individuals (18-37 years) with (n = 14) and without type 1 diabetes (n = 14). METHODS: Participants completed 30-min seated rest and three, 30-min bouts of semi-recumbent cycling at light, moderate, and vigorous metabolic heat productions (200, 250, 300 W/m2, respectively), each followed by 30-min recovery. Body core temperature (Tcore) and electrocardiogram were recorded throughout and analyzed during the final 5-min of rest and each exercise period. RESULTS: Relative to baseline, Tcore was increased in both groups, albeit to a greater extent in type 1 diabetes during vigorous exercise (T1D, 1.1 ± 0.3 °C; control, 0.8 ± 0.3 °C; P < 0.05). Overall HRV (as reflected by entropy) was attenuated throughout exercise relative to baseline in both groups, with the magnitude of the reduction greater in type 1 diabetes during vigorous exercise (T1D, - 108%; control, - 70%; P < 0.05). CONCLUSIONS: Given the negative correlations between decreased HRV and cardiac risk, our novel observations indicate that vigorous exercise in hot environments may pose a health concern for individuals with type 1 diabetes.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Diabetes Mellitus Tipo 1/fisiopatologia , Exercício Físico/fisiologia , Coração/fisiologia , Resposta ao Choque Térmico/fisiologia , Adolescente , Adulto , Glicemia/metabolismo , Temperatura Corporal/fisiologia , Diabetes Mellitus Tipo 1/sangue , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Descanso , Adulto Jovem
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