Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 4.652
Filtrar
1.
Gene ; 907: 148276, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38360128

RESUMO

Cold is a common stressor that threatens colonic health by affecting internal homeostasis. From the literature, Silent information regulator 2 (SIRT2) may have important roles during cold stress, but this conjecture requires investigation. To address this knowledge gap, we investigated the effects of SIRT2 on colonic injury in chronically cold-exposure mice. In a previous study, we showed that SIRT2 regulated p65 activation after cold exposure. In the current study, mice were exposed to 4 °C for 3 h/day for 3 weeks to simulate a chronic cold exposure environment. Chronic cold exposure shortened colon length, disrupted tight junctions in colonic epithelial tissue, and disordered colonic flora. Chronic cold exposure also increased p65 acetylation levels, promoted nuclear factor (NF)-κB activation, and increased the expression of its downstream pro-inflammatory factors, while SIRT2 knockdown aggravated the consequences of tissue structure disruption and increased inflammatory factors brought about by chronic cold exposure to some extent, but could alleviate the downregulation of colonic tight junction-related proteins to some extent. We also observed direct SIRT2 regulatory effects toward p65, and in Caco-2 cells treated with lipopolysaccharide (LPS), SIRT2 knockdown increased p65 acetylation levels and pro-inflammatory factor expression, while SIRT2 overexpression reversed these phenomena. Therefore, SIRT2 deletion exacerbated chronic cold exposure-induced colonic injury and p65 activation in mice. Mechanistically, p65 modification by SIRT2 via deacetylation may affect NF-κB signaling. These findings suggest that SIRT2 is a key target of colonic health maintenance under chronic cold exposure conditions.


Assuntos
Colo , NF-kappa B , Sirtuína 2 , Animais , Humanos , Camundongos , Células CACO-2 , Lipopolissacarídeos/farmacologia , NF-kappa B/metabolismo , Transdução de Sinais , Sirtuína 2/genética , Fator de Transcrição RelA/metabolismo , Colo/lesões , Colo/patologia , Temperatura Baixa/efeitos adversos
3.
Br J Community Nurs ; 28(12): 611-614, 2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38032722

RESUMO

As winter draws on it is timely to look at ways in which nurses in the community may be faced with problems, expected and unexpected, when their patients are particularly affected by cold conditions and at the precautions which need to be taken to avoid or lessen adverse effects on their health. As in the case of heat-related risks to health, examined in an earlier article, so too in the case of cold those most at risk are elderly patients and those who are vulnerable due to a pre-existing condition affecting health even in a more clement climate. Cold weather attracts extra legal responsibilities which are examined in this article.


Assuntos
Temperatura Baixa , Idoso , Humanos , Temperatura Baixa/efeitos adversos , Estações do Ano , Enfermeiras e Enfermeiros , Populações Vulneráveis
5.
Hand Surg Rehabil ; 42(2): 109-114, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36720347

RESUMO

OBJECTIVES: This systematic review seeks to understand whether cold intolerance (CI) improves with time and if there is any role for management strategies such as behavioural therapy, surgery, or pharmacotherapy. METHODS: Two independent reviewers used a predefined search strategy to query MEDLINE, PubMed, Embase, CINAHL, Cochrane Library, Web of Science and Google Scholar databases. Articles written in English, Studies of interventions (such as pharmacotherapy or behavioural therapy) for cold intolerance in adult patients with a history of hand injury along with prevalence over time were included for review. RESULTS: Seventeen studies were included, with twelve prognostic studies of the effect of time on CI, four studies of self management/behavioural therapies, and a single study of surgical treatment of neuromas. No studies of pharmacotherapies were identified for inclusion in the hand injury literature. Most studies (76.4%) were either prevalence or prospective cohort studies; no level I or II evidence studies were included. CONCLUSIONS: Cold intolerance does not resolve over time for the vast majority of patients. Behavioral and self-management studies have low efficacy and studies presented had a high risk of bias. There is a lack of evidence for the use of pharmacotherapy in CI and this could be considered for future studies.


Assuntos
Temperatura Baixa , Traumatismos da Mão , Adulto , Humanos , Temperatura Baixa/efeitos adversos
6.
Lancet ; 400(10364): 1693-1703, 2022 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-36343653

RESUMO

BACKGROUND: Haemodialysis centres have conventionally provided maintenance haemodialysis using a standard dialysate temperature (eg, 36·5°C) for all patients. Many centres now use cooler dialysate (eg, 36·0°C or lower) for potential cardiovascular benefits. We aimed to assess whether personalised cooler dialysate, implemented as centre-wide policy, reduced the risk of cardiovascular-related death or hospital admission compared with standard temperature dialysate. METHODS: MyTEMP was a pragmatic, two-arm, parallel-group, registry-based, open-label, cluster-randomised, superiority trial done at haemodialysis centres in Ontario, Canada. Eligible centres provided maintenance haemodialysis to at least 15 patients a week, and the medical director of each centre had to confirm that their centre would deliver the assigned intervention. Using covariate-constrained randomisation, we allocated 84 centres (1:1) to use either personalised cooler dialysate (nurses set the dialysate temperature 0·5-0·9°C below each patient's measured pre-dialysis body temperature, with a lowest recommended dialysate temperature of 35·5°C), or standard temperature dialysate (36·5°C for all patients and treatments). Patients and health-care providers were not masked to the group assignment; however, the primary outcome was recorded in provincial databases by medical coders who were unaware of the trial or the centres' group assignment. The primary composite outcome was cardiovascular-related death or hospital admission with myocardial infarction, ischaemic stroke, or congestive heart failure during the 4-year trial period. Analysis was by intention to treat. The study is registered at ClinicalTrials.gov, NCT02628366. FINDINGS: We assessed all of Ontario's 97 centres for inclusion into the study. Nine centres had less than 15 patients and one director requested that four of their seven centres not participate. 84 centres were recruited and on Feb 1, 2017, these centres were randomly assigned to administer personalised cooler dialysate (42 centres) or standard temperature dialysate (42 centres). The intervention period was from April 3, 2017, to March 31, 2021, and during this time the trial centres provided outpatient maintenance haemodialysis to 15 413 patients (about 4·3 million haemodialysis treatments). The mean dialysate temperature was 35·8°C in the cooler dialysate group and 36·4°C in the standard temperature group. The primary outcome occurred in 1711 (21·4%) of 8000 patients in the cooler dialysate group versus 1658 (22·4%) of 7413 patients in the standard temperature group (adjusted hazard ratio 1·00, 96% CI 0·89 to 1·11; p=0·93). The mean drop in intradialytic systolic blood pressure was 26·6 mm Hg in the cooler dialysate group and 27·1 mm Hg in the standard temperature group (mean difference -0·5 mm Hg, 99% CI -1·4 to 0·4; p=0·14). INTERPRETATION: Centre-wide delivery of personalised cooler dialysate did not significantly reduce the risk of major cardiovascular events compared with standard temperature dialysate. The rising popularity of cooler dialysate is called into question by this study, and the risks and benefits of cooler dialysate in some patient populations should be clarified in future trials. FUNDING: Canadian Institutes of Health Research, Heart and Stroke Foundation of Canada, Ontario Renal Network, Ontario Strategy for Patient-Oriented Research Support Unit, Dialysis Clinic, Inc., ICES (formerly known as the Institute for Clinical Evaluative Sciences), Lawson Health Research Institute, and Western University.


Assuntos
Soluções para Diálise , Diálise Renal , Humanos , Soluções para Diálise/efeitos adversos , Ontário , Diálise Renal/métodos , Resultado do Tratamento , Temperatura Baixa/efeitos adversos
7.
J Vasc Res ; 59(5): 303-313, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35728582

RESUMO

INTRODUCTION: Adrenoceptor and endothelin (ET) receptor-mediated vasoconstriction as well as endothelium-dependent vasodilation of human saphenous veins were compared before and after 20 h of cold storage. METHODS: Contractile responses to potassium chloride (KCl), norepinephrine (NE), and ET-1 as well as vasodilator responses to acetylcholine (ACh) were evaluated. RESULTS: Storage in HEPES-supplemented Dulbecco's modified Eagle's medium (HDMEM) diminished KCl induced contractile forces to 71% (p = 0.002) and NE induced contractions to 80% (p = 0.037), in contrast to HEPES-supplemented Krebs-Henseleit solution (HKH) and TiProtec solution. KCl-normalized NE contractions were not affected by storage. NE EC50 values were slightly lower (7.1E-8 vs. 7.5E-8, p = 0.019) after storage in HKH, with no changes after storage in the other solutions. Endothelium-dependent responses to ACh were not affected by storage. ET-1 induced contractions were attenuated after storage in HDMEM (77%, p = 0.002), HKH (75%, p = 0.020), and TiProtec (73%, p = 0.010) with no changes in normalized constrictions. ET-1 EC50 values were not affected by storage. CONCLUSION: Loss of contractility after storage in HDMEM may reflect the lower content of dextrose. There was no specific attenuation of adrenoceptor, ET-receptor, or ACh receptor mediated signal transduction after storage in any of the media. HKH or TiProtec are equally suitable cold storage solutions for ex vivo measurements.


Assuntos
Endotélio Vascular , Receptores Adrenérgicos , Receptores de Endotelina , Preservação de Tecido , Vasoconstrição , Vasodilatação , Humanos , Acetilcolina/farmacologia , Endotelina-1/farmacologia , Endotelinas/farmacologia , Endotélio , Endotélio Vascular/fisiopatologia , Glucose/farmacologia , HEPES/farmacologia , Norepinefrina/farmacologia , Cloreto de Potássio/farmacologia , Receptores Adrenérgicos/fisiologia , Receptores de Endotelina/fisiologia , Vasoconstrição/fisiologia , Vasodilatação/fisiologia , Vasodilatadores/farmacologia , Contração Muscular/fisiologia , Preservação de Tecido/métodos , Temperatura Baixa/efeitos adversos , Receptores Colinérgicos/fisiologia
8.
Pak J Pharm Sci ; 35(1): 9-13, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35221266

RESUMO

Banhasasim-tang (BST), a herbal medicine, has been used for nausea and fever from cold damage. This study aimed to investigate the protective effects of BST in cold restraint stress-induced gastric ulcers. Male Sprague Dawley rats were orally treated with various doses of BST including 0.25, 0.5, 1, 3, 6, 9, 12 and 18g/kg based on the human daily intake dose. After treatment once per day for 3 days, rats were restrained into the cold stress chamber for 12h at 4°C to induce gastric ulcers. Gastric hemorrhagic ulcer area was evaluated and serum adrenocorticotropic hormone (ACTH), corticosterone, epinephrine and dopamine levels were determined. Compared to cold stress-induced gastric ulcer rats, hemorrhage ulcer areas were reduced in BST-treated stomach tissues at all concentrations. Increased serum ACTH, corticosterone and epinephrine levels were significantly decreased by BST treatment in cold stress-induced gastric ulcer rats. Moreover, there were increments of serum dopamine levels in 3 and 6g/kg of BST-treated groups. Taken together, BST positively ameliorated cold restraint stress-induced gastric hemorrhage with decrease in serum stress-related biomarkers such as ACTH, corticosterone, epinephrine and dopamine. The 3-6-fold of human daily intake dose of BST exhibited protective effects as a herbal medicine for gastric ulcers.


Assuntos
Temperatura Baixa/efeitos adversos , Fitoterapia , Úlcera Gástrica/tratamento farmacológico , Estresse Fisiológico , Animais , Dopamina/metabolismo , Medicina Herbária , Masculino , Plantas Medicinais , Ratos , Ratos Sprague-Dawley , República da Coreia , Úlcera Gástrica/etiologia
9.
Molecules ; 27(3)2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35164009

RESUMO

The development of non-destructive methods for early detection of cold stress of plants and the identification of cold-tolerant cultivars is highly needed in crop breeding programs. Current methods are either destructive, time-consuming or imprecise. In this study, soybean leaves' spectra were acquired in the near infrared (NIR) range (588-1025 nm) from five cultivars genetically engineered to have different levels of cold stress tolerance. The spectra were acquired at the optimal growing temperature 27 °C and when the temperature was decreased to 22 °C. In this paper, we report the results of the aquaphotomics analysis performed with the objective of understanding the role of the water molecular system in the early cold stress response of all cultivars. The raw spectra and the results of Principal Component Analysis, Soft Independent Modeling of Class Analogies and aquagrams showed consistent evidence of huge differences in the NIR spectral profiles of all cultivars under normal and mild cold stress conditions. The SIMCA discrimination between the plants before and after stress was achieved with 100% accuracy. The interpretation of spectral patterns before and after cold stress revealed major changes in the water molecular structure of the soybean leaves, altered carbohydrate and oxidative metabolism. Specific water molecular structures in the leaves of soybean cultivars were found to be highly sensitive to the temperature, showing their crucial role in the cold stress response. The results also indicated the existence of differences in the cold stress response of different cultivars, which will be a topic of further research.


Assuntos
Aclimatação/fisiologia , Resposta ao Choque Frio/fisiologia , /química , Temperatura Baixa/efeitos adversos , Fabaceae/química , Fabaceae/fisiologia , Fotometria , Melhoramento Vegetal/métodos , Folhas de Planta/química , Espectroscopia de Luz Próxima ao Infravermelho , Estresse Fisiológico/fisiologia , Temperatura , Água/química
10.
Environ Sci Pollut Res Int ; 29(24): 35760-35767, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35060041

RESUMO

Previous studies have reported that daily average temperature is connected with respiratory diseases (RD), but proof is limited for the influence of the extreme low temperature on RD in Lanzhou, a northwestern China of temperate area. Generalized additive model (GAM) was built in this work to describe the relationship between daily mean temperature and RD in Lanzhou, China from 2012 to 2017. The results indicated that the exposure-response curve was inverse J-shaped, showing the lower the temperature, the larger the relative risk (RR). The RR of daily emergency room (ER) admissions in P5 extreme low temperature (the temperature below the fifth percentile, etc.) was larger than that in P10. The P5 extreme low temperature has the strongest effect at lag 0, and the RRs were 1.043 (95% CI: 1.030, 1.055) for the total, 1.031 (95% CI: 1.015, 1.046) for males and 1.058 (95% CI: 1.039, 1.077) for females. For different age groups, the largest RRs were 1.026 (95% CI: 1.013, 1.039) for the children (age < 16 years) at lag 5, 1.057 (95% CI: 1.030, 1.085) for the young adults (aged 16-45 years), 1.060 (95% CI: 1.023, 1.099) for the middle-aged (aged 46-60 years) and 1.121 (95% CI: 1.077, 1.166) for the elderly group of age > 60 years. Meanwhile, females and the elderly were more vulnerable to extreme temperature. The results could strengthen the scientific evidence of effects of extreme low temperature on RD in temperate areas.


Assuntos
Poluição do Ar , Temperatura Baixa , Transtornos Respiratórios , Adolescente , Adulto , Idoso , Criança , China/epidemiologia , Temperatura Baixa/efeitos adversos , Feminino , Temperatura Alta , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Respiratórios/epidemiologia , Adulto Jovem
11.
Plant Sci ; 314: 111104, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34895541

RESUMO

Low temperature during the vegetative stage depresses rice tillering. Zinc (Zn) can promote rice tiller growth and improve plant resistance to abiotic stress. Consequently, Zn application after low temperature might be an effective approach to promote rice tiller recovery. A water culture experiment with treatments of two temperatures (12 °C and 20 °C) and three Zn concentrations (0.08 µM, 0.15 µM and 0.31 µM ZnSO4·7H2O) was conducted to determine by analyzing rice tiller growth, nutrient absorption and hormones metabolism. The results showed that low temperature reduced rice tiller numbers and leaf age, decreased as well. Increasing Zn application after low temperature could enhance not only rice tiller growth rate but also N metabolism and tillering recovery, and correlation analysis showed a significantly positive correlation between tiller increment and Zn and N accumulation after low temperature. In addition, higher cytokinin (CTK)/auxin (IAA) ratio was maintained by promoted synthesis of CTK and IAA as well as enhanced IAA transportation from tiller buds to other parts with increased Zn application after cold stress, which resulted in accelerated germination and growth of tiller buds. These results highlighted that Zn application after low temperature promoted rice tiller recovery by increasing N and Zn accumulation and maintaining hormones balance.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Temperatura Baixa/efeitos adversos , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Zinco/metabolismo
12.
JAMA Cardiol ; 7(2): 167-174, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34775507

RESUMO

Importance: Atrial fibrillation (AF) is the most common arrhythmia. Although patients have reported that various exposures determine when and if an AF event will occur, a prospective evaluation of patient-selected triggers has not been conducted, and the utility of characterizing presumed AF-related triggers for individual patients remains unknown. Objective: To test the hypothesis that n-of-1 trials of self-selected AF triggers would enhance AF-related quality of life. Design, Setting, and Participants: A randomized clinical trial lasting a minimum of 10 weeks tested a smartphone mobile application used by symptomatic patients with paroxysmal AF who owned a smartphone and were interested in testing a presumed AF trigger. Participants were screened between December 22, 2018, and March 29, 2020. Interventions: n-of-1 Participants received instructions to expose or avoid self-selected triggers in random 1-week blocks for 6 weeks, and the probability their trigger influenced AF risk was then communicated. Controls monitored their AF over the same time period. Main Outcomes and Measures: AF was assessed daily by self-report and using a smartphone-based electrocardiogram recording device. The primary outcome comparing n-of-1 and control groups was the Atrial Fibrillation Effect on Quality-of-Life (AFEQT) score at 10 weeks. All participants could subsequently opt for additional trigger testing. Results: Of 446 participants who initiated (mean [SD] age, 58 [14] years; 289 men [58%]; 461 White [92%]), 320 (72%) completed all study activities. Self-selected triggers included caffeine (n = 53), alcohol (n = 43), reduced sleep (n = 31), exercise (n = 30), lying on left side (n = 17), dehydration (n = 10), large meals (n = 7), cold food or drink (n = 5), specific diets (n = 6), and other customized triggers (n = 4). No significant differences in AFEQT scores were observed between the n-of-1 vs AF monitoring-only groups. In the 4-week postintervention follow-up period, significantly fewer daily AF episodes were reported after trigger testing compared with controls over the same time period (adjusted relative risk, 0.60; 95% CI, 0.43- 0.83; P < .001). In a meta-analysis of the individualized trials, only exposure to alcohol was associated with significantly heightened risks of AF events. Conclusions and Relevance: n-of-1 Testing of AF triggers did not improve AF-associated quality of life but was associated with a reduction in AF events. Acute exposure to alcohol increased AF risk, with no evidence that other exposures, including caffeine, more commonly triggered AF. Trial Registration: ClinicalTrials.gov Identifier: NCT03323099.


Assuntos
Fibrilação Atrial/prevenção & controle , Qualidade de Vida , Adulto , Idoso , Consumo de Bebidas Alcoólicas/efeitos adversos , Fibrilação Atrial/etiologia , Fibrilação Atrial/fisiopatologia , Cafeína/efeitos adversos , Temperatura Baixa/efeitos adversos , Desidratação/complicações , Eletrocardiografia , Exercício Físico/efeitos adversos , Comportamento Alimentar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Posicionamento do Paciente/efeitos adversos , Autorrelato , Estudos de Caso Único como Assunto , Sono , Smartphone , Dispositivos Eletrônicos Vestíveis
13.
J Stroke Cerebrovasc Dis ; 31(1): 106156, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34735898

RESUMO

OBJECTIVE: Although several studies have reported that some meteorological factors such as ambient temperature and atmospheric pressure, affect the incidence of spontaneous intracerebral hemorrhage (ICH), the correlation remains unclear. This retrospective time-series analysis was aimed to clarify the effects of meteorological parameters on the incidence of ICH. MATERIALS AND METHODS: Data of patients with ICH were obtained from a population-based survey of acute stroke patients between April 2016 and March 2019. All days during the study period were categorized into "no ICH day" when no ICHs occurred, "single ICH day" when only one ICH occurred, and "cluster day" when two or more ICHs occurred. Meteorological data were compared for among the three categories. RESULTS: 1,691 ICH patients from 19 hospitals were registered. In a total of 1,095 days, 250 were categorized as no ICH days, 361 as single ICH days, and 484 as cluster days. Daily ambient temperature declined in parallel with the daily number of ICHs, and it was a significant predictor for single ICH days and cluster days. Furthermore, the incidence of ICH in patients aged 65 years or above, men, those who emerged at home, those with modified Rankin Scale 3-5; and those with hypertension; and ICHs in the basal ganglia, brain stem, and cerebellum were more likely to be affected by low ambient temperature. CONCLUSION: Daily ambient temperature was significantly associated with ICH incidence. Patients' activity, history of hypertension, and location of hemorrhage were also related to the impact of low ambient temperature on the incidence of ICH.


Assuntos
Hemorragia Cerebral , Temperatura Baixa , Idoso , Hemorragia Cerebral/epidemiologia , Temperatura Baixa/efeitos adversos , Humanos , Japão/epidemiologia , Masculino , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral
14.
Gene ; 807: 145952, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34500049

RESUMO

Extreme temperature is one of the serious threats to crop production in present and future scenarios of global climate changes. Lentil (Lens culinaris) is an important crop, and there is a serious lack of genetic information regarding environmental and temperature stresses responses. This study is the first report of evaluation of key genes and molecular mechanisms related to temperature stresses in lentil using the RNA sequencing technique. De novo transcriptome assembly created 44,673 contigs and differential gene expression analysis revealed 7494 differentially expressed genes between the temperature stresses and control group. Basic annotation of generated transcriptome assembly in our study led to the identification of 2765 novel transcripts that have not been identified yet in lentil genome draft v1.2. In addition, several unigenes involved in mechanisms of temperature sensing, calcium and hormone signaling and DNA-binding transcription factor activity were identified. Also, common mechanisms in response to temperature stresses, including the proline biosynthesis, the photosynthetic light reactions balancing, chaperone activity and circadian rhythms, are determined by the hub genes through the protein-protein interaction networks analysis. Deciphering the mechanisms of extreme temperature tolerance would be a new way for developing crops with enhanced plasticity against climate change. In general, this study has identified set of mechanisms and various genes related to cold and heat stresses which will be useful in better understanding of the lentil's reaction to temperature stresses.


Assuntos
Lens (Planta)/crescimento & desenvolvimento , Lens (Planta)/genética , Estresse Fisiológico/genética , Mudança Climática , Temperatura Baixa/efeitos adversos , Resposta ao Choque Frio/genética , Produtos Agrícolas/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Resposta ao Choque Térmico/genética , Resposta ao Choque Térmico/fisiologia , Temperatura Alta/efeitos adversos , Anotação de Sequência Molecular/métodos , Fotossíntese , Mapas de Interação de Proteínas/genética , Temperatura , Transcriptoma/genética
15.
Andrology ; 10(2): 279-290, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34628730

RESUMO

BACKGROUND: Testicular tissue freezing is proposed for fertility preservation to (pre)pubertal boys with cancer before highly gonadotoxic treatment. Studies accurately comparing human (pre)pubertal testicular tissue quality before freezing and after thawing are exceptional. No study has reported this approach in a systematic manner and routine care. OBJECTIVES: To assess the impact of a control slow freezing protocol on testicular tissue architecture and integrity of (pre)pubertal boys after thawing. MATERIALS AND METHODS: (Pre)pubertal boys (n = 87) with cancer from 8 Reproductive Biology Laboratories of the French CECOS network benefited from testicular tissue freezing before hematopoietic stem cell transplantation. Seminiferous tubule cryodamage was determined histologically by scoring morphological alterations and by quantifying intratubular spermatogonia and the expression of DNA replication and repair marker in frozen-thawed testicular fragments. RESULTS: A significant increase in nuclear and epithelial score alterations was observed after thawing (p < 0.0001). The global lesional score remained lower than 1.5 and comparable to fresh testicular tissue. The number of intratubular spermatogonia and the expression of DNA replication and repair marker in spermatogonia and Sertoli cells did not vary significantly after thawing. These data showed the good preservation of the seminiferous tubule integrity and architecture after thawing, as previously reported in our studies performed in prepubertal mice and rats. DISCUSSION: The current study reports, for the first time, the development of a semi-quantitative analysis of cryodamage in human (pre)pubertal testicular tissue, using a rapid and useful tool that can be proposed in routine care to develop an internal and external quality control for testicular tissue freezing. This tool can also be used when changing one or several parameters of the freezing-thawing procedure. CONCLUSION: Control slow freezing protocol without seeding maintains the seminiferous tubule architecture and integrity, the concentration of spermatogonia and the expression of DNA replication and repair marker in spermatogonia and Sertoli cells after thawing.


Assuntos
Temperatura Baixa/efeitos adversos , Criopreservação/métodos , Testículo/patologia , Adolescente , Criança , Pré-Escolar , Preservação da Fertilidade/efeitos adversos , Preservação da Fertilidade/métodos , França , Humanos , Lactente , Masculino , Neoplasias/terapia , Estudos Prospectivos , Puberdade , Túbulos Seminíferos/patologia , Células de Sertoli/patologia , Espermatogônias/patologia
16.
J Clin Endocrinol Metab ; 107(2): 450-461, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34570185

RESUMO

CONTEXT: Thyroid hormone (TH) is crucial for the adaptation to cold. OBJECTIVE: To evaluate the effect of hyperthyroidism on resting energy expenditure (REE), cold-induced thermogenesis (CIT) and changes in body composition and weight. METHODS: This was a prospective cohort study at the endocrine outpatient clinic of a tertiary referral center. Eighteen patients with overt hyperthyroidism were included. We measured REE during hyperthyroidism, after restoring euthyroid TH levels and after 3 months of normal thyroid function. In 14 of the 18 patients, energy expenditure (EE) was measured before and after a mild cold exposure of 2 hours and CIT was the difference between EEcold and EEwarm. Skin temperatures at 8 positions were recorded during the study visits. Body composition was assessed by dual X-ray absorption. RESULTS: Free thyroxine (fT4) and free triiodothyronine (fT3) decreased significantly over time (fT4, P = .0003; fT3, P = .0001). REE corrected for lean body mass (LBM) decreased from 42 ±â€…6.7 kcal/24 hour/kg LBM in the hyperthyroid to 33 ±â€…4.4 kcal/24 hour/kg LBM (-21%, P < .0001 vs hyperthyroid) in the euthyroid state and 3 months later to 33 ±â€…5.2 kcal/24 hour/kg LBM (-21%, P = .0022 vs hyperthyroid, overall P < .0001). fT4 (P = .0001) and fT3 (P < 0.0001) were predictors of REE. CIT did not change from the hyperthyroid to the euthyroid state (P = .96). Hyperthyroidism led to increased skin temperature at warm ambient conditions but did not alter core body temperature, nor skin temperature after cold exposure. Weight regain and body composition were not influenced by REE and CIT during the hyperthyroid state. CONCLUSION: CIT is not increased in patients with overt hyperthyroidism.


Assuntos
Metabolismo Basal/fisiologia , Hipertireoidismo/metabolismo , Termogênese , Tiroxina/metabolismo , Tri-Iodotironina/metabolismo , Antagonistas Adrenérgicos/uso terapêutico , Adulto , Idoso , Composição Corporal , Temperatura Baixa/efeitos adversos , Feminino , Humanos , Hipertireoidismo/sangue , Hipertireoidismo/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Testes de Função Tireóidea , Tiroxina/sangue , Tri-Iodotironina/sangue , Adulto Jovem
17.
Oxid Med Cell Longev ; 2021: 8578452, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34868457

RESUMO

PURPOSE: We explored the role of ROS in cold-induced vasoconstriction and corresponding mechanism. METHODS: Three experiments were performed. First, we measured blood flow in human hands before and after cold exposure. Second, 24 mice were randomly divided into 3 groups: 8 mice received saline injection, 8 received subcutaneous Tempol injection, and 8 received intrathecal Tempol injection. After 30 min, we determined blood flow in the skin before and after cold exposure. Finally, we used Tempol, CCG-1423, and Go 6983 to pretreat HAVSMCs and HUVECs for 24 h. Then, cells in the corresponding groups were exposed to cold (6 h, 4°C). After cold exposure, the cytoskeleton was stained. Intracellular Ca2+ and ROS levels were measured by flow cytometry and fluorescence microscopy. We measured protein expression via Western blotting. RESULTS: In the first experiment, after cold exposure, maximum skin blood flow decreased to 118.4 ± 50.97 flux units. Then, Tempol or normal saline pretreatment did not change skin blood flow. Unlike intrathecal Tempol injection, subcutaneous Tempol injection increased skin blood flow after cold exposure. Finally, cold exposure for 6 h shrank the cells, making them narrower, and increased intracellular Ca2+ and ROS levels in HUVECs and HAVSMCs. Tempol reduced cell shrinkage and decreased intracellular Ca2+ levels. In addition, Tempol decreased intracellular ROS levels. Cold exposure increased RhoA, Rock1, p-MLC-2, ET-1, iNOS, and p-PKC expression and decreased eNOS expression. Tempol or CCG-1423 pretreatment decreased RhoA, Rock1, and p-MLC-2 levels in HAVSMCs. Furthermore, Tempol or Go 6983 pretreatment decreased ET-1, iNOS, and p-PKC expression and increased eNOS expression in HUVECs. CONCLUSION: ROS mediate the vasoconstrictor response within the cold-induced vascular response, and ROS in blood vessel tissues rather than nerve fibers are involved in vasoconstriction via the ROS/RhoA/ROCK1 and ROS/PKC/ET-1 pathways in VSMCs and endothelial cells.


Assuntos
Temperatura Baixa/efeitos adversos , Espécies Reativas de Oxigênio/metabolismo , Vasoconstrição/fisiologia , Adulto , Animais , Feminino , Humanos , Masculino , Camundongos
18.
Environ Health Prev Med ; 26(1): 104, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34641787

RESUMO

BACKGROUND: Excess winter mortality caused by cardiovascular disease is particularly profound in cold houses. Consistent with this, accumulating evidence indicates that low indoor temperatures at home increase blood pressure. However, it remains unclear whether low indoor temperatures affect other cardiovascular biomarkers. In its latest list of priority medical devices for management of cardiovascular diseases, the World Health Organization (WHO) included electrocardiography systems as capital medical devices. We therefore examined the association between indoor temperature and electrocardiogram findings. METHODS: We collected electrocardiogram data from 1480 participants during health checkups. We also measured the indoor temperature in the living room and bedroom for 2 weeks in winter, and divided participants into those living in warm houses (average exposure temperature ≥ 18 °C), slightly cold houses (12-18 °C), and cold houses (< 12 °C) in accordance with guidelines issued by the WHO and United Kingdom. The association between indoor temperature (warm vs. slightly cold vs. cold houses) and electrocardiogram findings was analyzed using multivariate logistic regression models, with adjustment for confounders such as demographics (e.g., age, sex, body mass index, household income), lifestyle (e.g., eating habit, exercise, smoking, alcohol drinking), and region. RESULTS: The average temperature at home was 14.7 °C, and 238, 924, and 318 participants lived in warm, slightly cold, and cold houses, respectively. Electrocardiogram abnormalities were observed in 17.6%, 25.4%, and 30.2% of participants living in warm, slightly cold, and cold houses, respectively (p = 0.003, chi-squared test). Compared to participants living in warm houses, the odds ratio of having electrocardiogram abnormalities was 1.79 (95% confidence interval: 1.14-2.81, p = 0.011) for those living in slightly cold houses and 2.18 (95% confidence interval: 1.27-3.75, p = 0.005) for those living in cold houses. CONCLUSIONS: In addition to blood pressure, living in cold houses may have adverse effects on electrocardiogram. Conversely, keeping the indoor thermal environment within an appropriate range through a combination of living in highly thermal insulated houses and appropriate use of heating devices may contribute to good cardiovascular health. TRIAL REGISTRATION: The trial was retrospectively registered on 27 Dec 2017 to the University hospital Medical Information Network Clinical Trials Registry (UMIN-CTR, https://www.umin.ac.jp/ctr/ , registration identifier number UMIN000030601 ).


Assuntos
Temperatura Baixa/efeitos adversos , Eletrocardiografia , Habitação , Temperatura , Idoso , Doenças Cardiovasculares/prevenção & controle , Estudos Transversais , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade
20.
BMC Plant Biol ; 21(1): 460, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34625030

RESUMO

BACKGROUND: Magonlia denudata is an important perennial tree species of the Magnoliaceae family, known for its ornamental value, resistance to smoke pollution and wind, role in air purification, and robust cold tolerance. In this study, a high-throughput transcriptome analysis of leaf buds was performed, and gene expression following artificial acclimation 22 °C, 4 °C and 0 °C, was compared by RNA sequencing. RESULTS: Over 426 million clean reads were produced from three libraries (22 °C, 4 °C and 0 °C). A total of 74,503 non-redundant unigenes were generated, with an average length of 1173.7 bp (N50 = 1548). Based on transcriptional results, 357 and 235 unigenes were identified as being upregulated and downregulated under cold stress conditions, respectively. Differentially expressed genes were annotated using Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes pathway analyses. The transcriptomic analysis focused on carbon metabolism and plant hormone signal transduction associated with cold acclimation. Transcription factors such as those in the basic helix-loop-helix and AP2/ERF families were found to play an important role in M. denudata cold acclimation. CONCLUSION: M. denudata exhibits responses to non-freezing cold temperature (4 °C) to increase its cold tolerance. Cold resistance was further strengthened with cold acclimation under freezing conditions (0 °C). Cold tolerance genes, and cold signaling transcriptional pathways, and potential functional key components for the regulation of the cold response were identified in M. denudata. These results provide a basis for further studies, and the verification of key genes involved in cold acclimation responses in M. denudata lays a foundation for developing breeding programs for Magnoliaceae species.


Assuntos
Aclimatação/genética , Temperatura Baixa/efeitos adversos , Resposta ao Choque Frio/genética , Magnolia/genética , Magnolia/fisiologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/genética , Aclimatação/fisiologia , Resposta ao Choque Frio/fisiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Variação Genética , Genótipo , Transdução de Sinais , Fatores de Transcrição
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...