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1.
Oxid Med Cell Longev ; 2022: 9927602, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35154578

RESUMO

In recent decades, the use of energy-based devices has substantially increased the incidence of iatrogenic thermal injury to nerves (cauterization, etc.). While recovery of the nerve after thermal injury is important, the changes in neural structure, function, and peripheral inflammatory reactions postinjury remain unclear. This study is aimed at demonstrating the changes mentioned above during the acute, subacute, and chronic stages of nerve reinnervation after thermal injury. Spontaneous reinnervation was evaluated, including the neural structures, nerve conduction abilities, and muscle regeneration. These effects vary depending on the severity of thermal injury (slight, moderate, and severe). Peripheral inflammatory reactions, as impediments to reinnervation, were found in significant numbers 3 days after thermal injury, exhibiting high expression of IL-1ß and TNF-α, but low expression of IL-10. Our findings reveal the pathogenesis of peripheral nerve reinnervation after thermal injury, which will assist in selecting appropriate treatments in further research.


Assuntos
Fascia Lata/inervação , Músculos Isquiossurais/inervação , Temperatura Alta/efeitos adversos , Regeneração Nervosa/fisiologia , Traumatismos dos Nervos Periféricos/etiologia , Traumatismos dos Nervos Periféricos/fisiopatologia , Nervo Isquiático/lesões , Nervo Isquiático/fisiologia , Animais , Axônios/fisiologia , Citocinas/sangue , Modelos Animais de Doenças , Fascia Lata/fisiologia , Músculos Isquiossurais/fisiologia , Inflamação/sangue , Inflamação/etiologia , Inflamação/fisiopatologia , Masculino , Traumatismos dos Nervos Periféricos/sangue , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica
2.
Sci Rep ; 12(1): 3071, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35197522

RESUMO

One of the complications of esophageal endoscopic submucosal dissection (ESD) is postoperative stricture formation. Stenosis formation is associated with inflammation and fibrosis in the healing process. We hypothesized that the degree of thermal damage caused by the device is related to stricture formation. We aimed to reveal the relationship between thermal damage and setting value of the device. We energized a resected porcine esophagus using the ESD device (Flush Knife 1.5). We performed 10 energization points for 1 s, 3 s, and 5 s at four setting values of the device. We measured the amount of current flowing to the conducted points and the temperature and evaluated the effects of thermal damage pathologically. As results, the mean highest temperatures for 1 s were I (SWIFT Effect3 Wat20): 61.19 °C, II (SWIFT Effect3 Wat30): 77.28 °C, III (SWIFT Effect4 Wat20): 94.50 °C, and IV (SWIFT Effect4 Wat30): 94.29 °C. The mean heat denaturation areas were I: 0.84 mm2, II: 1.00 mm2, III: 1.91 mm2, and IV: 1.54 mm2. The mean highest temperature and mean heat denaturation area were significantly correlated (P < 0.001). In conclusion, Low-current ESD can suppress the actual temperature and thermal damage in the ESD wound.


Assuntos
Ressecção Endoscópica de Mucosa/efeitos adversos , Ressecção Endoscópica de Mucosa/métodos , Mucosa Esofágica/lesões , Esofagectomia/efeitos adversos , Esofagectomia/instrumentação , Esofagoscópios/efeitos adversos , Esofagoscopia/efeitos adversos , Esofagoscopia/métodos , Temperatura Alta/efeitos adversos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Animais , Ressecção Endoscópica de Mucosa/instrumentação , Esofagectomia/métodos , Modelos Anatômicos , Suínos
3.
Int J Mol Sci ; 23(3)2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35163242

RESUMO

Under the global warming scenario, obtaining plant material with improved tolerance to abiotic stresses is a challenge for afforestation programs. In this work, maritime pine (Pinus pinaster Aiton) plants were produced from somatic embryos matured at different temperatures (18, 23, or 28 °C, named after M18, M23, and M28, respectively) and after 2 years in the greenhouse a heat stress treatment (45 °C for 3 h/day for 10 days) was applied. Temperature variation during embryo development resulted in altered phenotypes (leaf histology, proline content, photosynthetic rates, and hormone profile) before and after stress. The thickness of chlorenchyma was initially larger in M28 plants, but was significantly reduced after heat stress, while increased in M18 plants. Irrespective of their origin, when these plants were subjected to a heat treatment, relative water content (RWC) and photosynthetic carbon assimilation rates were not significantly affected, although M18 plants increased net photosynthesis rate after 10 days recovery (tR). M18 plants showed proline contents that increased dramatically (2.4-fold) when subjected to heat stress, while proline contents remained unaffected in M23 and M28 plants. Heat stress significantly increased abscisic acid (ABA) content in the needles of maritime pine plants (1.4-, 3.6- and 1.9-fold in M18, M23, and M28 plants, respectively), while indole-3-acetic acid content only increased in needles from M23 plants. After the heat treatment, the total cytokinin contents of needles decreased significantly, particularly in M18 and M28 plants, although levels of active forms (cytokinin bases) did not change in M18 plants. In conclusion, our results suggest that maturation of maritime pine somatic embryos at lower temperature resulted in plants with better performance when subjected to subsequent high temperature stress, as demonstrated by faster and higher proline increase, lower increases in ABA levels, no reduction in active cytokinin, and a better net photosynthesis rate recovery.


Assuntos
Resposta ao Choque Térmico/genética , Pinus/crescimento & desenvolvimento , Pinus/genética , Agricultura/métodos , Secas , Resposta ao Choque Térmico/fisiologia , Temperatura Alta/efeitos adversos , Fotossíntese/fisiologia , Folhas de Planta/metabolismo , Técnicas de Embriogênese Somática de Plantas/métodos , Temperatura
4.
BMJ Open ; 12(1): e052537, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35074814

RESUMO

INTRODUCTION: The European climate is getting warmer and the impact on childhood health and development is insufficiently understood. Equally, how heat-related health risks can be reduced through nature-based solutions, such as exposure to urban natural environments, is unknown. Green CURe In Outdoor CITY spaces (Green CURIOCITY) will analyse how heat exposure during pregnancy affects birth outcomes and how long-term heat exposure may influence children's neurodevelopment. We will also investigate if adverse effects can be mitigated by urban natural environments. A final goal is to visualise intraurban patterns of heat vulnerability and assist planning towards healthier cities. METHODS AND ANALYSIS: We will use existing data from the Human Early-Life Exposure cohort, which includes information on birth outcomes and neurodevelopment from six European birth cohorts. The cohort is linked to data on prenatal heat exposure and impact on birth outcomes will be analysed with logistic regression models, adjusting for air pollution and noise and sociobehavioural covariates. Similarly, impact of cumulative and immediate heat exposure on neurodevelopmental outcomes at age 5 will be assessed. For both analyses, the potentially moderating impact of natural environments will be quantified. For visualisation, Geographical information systems data will be combined to develop vulnerability maps, demonstrating urban 'hot spots' where the risk of negative impacts of heat is aggravated due to sociodemographic and land use patterns. Finally, geospatial and meteorological data will be used for informing GreenUr, an existing software prototype developed by the WHO Regional Office for Europe to quantify health impacts and augment policy tools for urban green space planning. ETHICS AND DISSEMINATION: The protocol was approved by the Comité Ético de Investigación Clínica Parc de Salut MAR, Spain. Findings will be published in peer-reviewed journals and presented at policy events. Through stakeholder engagement, the results will also reach user groups and practitioners.


Assuntos
Temperatura Alta , Parques Recreativos , Poluição do Ar , Criança , Pré-Escolar , Cidades , Estudos de Coortes , Feminino , Temperatura Alta/efeitos adversos , Humanos , Gravidez
5.
Sci Rep ; 12(1): 313, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35013399

RESUMO

As a powerful and attractive method for detecting gene expression, qRT-PCR has been broadly used in aquaculture research. Understanding the biology of taimen (Hucho taimen) has drawn increasing interest because of its ecological and economic value. Stable reference genes are required for the reliable quantification of gene expression, but such genes have not yet been optimized for taimen. In this study, the stability levels of 10 commonly used candidate reference genes were evaluated using geNorm, NormFinder, BestKeeper, and RefFinder. The expression levels of the 10 genes were detected using 240 samples from 48 experimental groups consisting of 40 individuals treated under four heat-stress conditions (18, 20, 22, and 24 °C) for 24 h and 26 °C for 4, 24, 48, and 72 h. Six tissues (blood, heart, brain, gill, skin, and liver) were collected from each individual. Ribosomal protein S29 (RPS29) and ribosomal protein L19 (RPL19) were the most stable genes among all of the samples, whereas 28S ribosomal RNA (28S rRNA), attachment region binding protein (ARBP), and 18S ribosomal RNA (18S rRNA) were the least stable. These results were verified by an expression analysis of taimen heat-stress genes (heat shock protein 60, hsp60, and heat shock protein 70, hsp70). In conclusion, RPS29 and RPL19 are the optimal reference genes for qRT-PCR analyses of taimen, irrespective of the tissue and experimental conditions. These results allow the reliable study of gene expression in taimen.


Assuntos
Chaperonina 60/genética , Proteínas de Peixes/genética , Proteínas de Choque Térmico HSP70/genética , Resposta ao Choque Térmico , Temperatura Alta/efeitos adversos , Reação em Cadeia da Polimerase em Tempo Real/normas , Salmonidae/genética , Animais , Aquicultura , Chaperonina 60/metabolismo , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica , Proteínas de Choque Térmico HSP70/metabolismo , Padrões de Referência , Salmonidae/metabolismo
6.
Sci Rep ; 12(1): 1174, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-35064187

RESUMO

To predict global warming impacts on parasitism, we should describe the thermal tolerance of all players in host-parasite systems. Complex life-cycle parasites such as trematodes are of particular interest since they can drive complex ecological changes. This study evaluates the net response to temperature of the infective larval stage of Himasthla elongata, a parasite inhabiting the southwestern Baltic Sea. The thermal sensitivity of (i) the infected and uninfected first intermediate host (Littorina littorea) and (ii) the cercarial emergence, survival, self-propelling, encystment, and infection capacity to the second intermediate host (Mytilus edulis sensu lato) were examined. We found that infection by the trematode rendered the gastropod more susceptible to elevated temperatures representing warm summer events in the region. At 22 °C, cercarial emergence and infectivity were at their optimum while cercarial survival was shortened, narrowing the time window for successful mussel infection. Faster out-of-host encystment occurred at increasing temperatures. After correcting the cercarial emergence and infectivity for the temperature-specific gastropod survival, we found that warming induces net adverse effects on the trematode transmission to the bivalve host. The findings suggest that gastropod and cercariae mortality, as a tradeoff for the emergence and infectivity, will hamper the possibility for trematodes to flourish in a warming ocean.


Assuntos
Aclimatação , Organismos Aquáticos/fisiologia , Gastrópodes/parasitologia , Trematódeos/patogenicidade , Infecções por Trematódeos/veterinária , Animais , Cercárias/isolamento & purificação , Cercárias/patogenicidade , Cercárias/fisiologia , Aquecimento Global , Interações Hospedeiro-Parasita , Temperatura Alta/efeitos adversos , Mytilus edulis , Estações do Ano , Trematódeos/isolamento & purificação , Trematódeos/fisiologia , Infecções por Trematódeos/diagnóstico , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/transmissão
7.
Sci Rep ; 12(1): 369, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35013464

RESUMO

The risk of kidney stone presentations increases after hot days, likely due to greater insensible water losses resulting in more concentrated urine and altered urinary flow. It is thus expected that higher temperatures from climate change will increase the global prevalence of kidney stones if no adaptation measures are put in place. This study aims to quantify the impact of heat on kidney stone presentations through 2089, using South Carolina as a model state. We used a time series analysis of historical kidney stone presentations (1997-2014) and distributed lag non-linear models to estimate the temperature dependence of kidney stone presentations, and then quantified the projected impact of climate change on future heat-related kidney stone presentations using daily projections of wet-bulb temperatures to 2089, assuming no adaptation or demographic changes. Two climate change models were considered-one assuming aggressive reduction in greenhouse gas emissions (RCP 4.5) and one representing uninibited greenhouse gas emissions (RCP 8.5). The estimated total statewide kidney stone presentations attributable to heat are projected to increase by 2.2% in RCP 4.5 and 3.9% in RCP 8.5 by 2085-89 (vs. 2010-2014), with an associated total excess cost of ~ $57 million and ~ $99 million, respectively.


Assuntos
Mudança Climática , Temperatura Alta/efeitos adversos , Cálculos Renais/epidemiologia , Previsões , Aquecimento Global , Efeito Estufa , Gases de Efeito Estufa , Custos de Cuidados de Saúde/tendências , Humanos , Cálculos Renais/diagnóstico , Cálculos Renais/economia , Cálculos Renais/terapia , Dinâmica não Linear , Medição de Risco , Fatores de Risco , South Carolina/epidemiologia , Fatores de Tempo
8.
Plant Physiol ; 188(1): 285-300, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-34643728

RESUMO

Increasing night-time temperatures are a major threat to sustaining global rice (Oryza sativa L.) production. A simultaneous increase in [CO2] will lead to an inevitable interaction between elevated [CO2] (e[CO2]) and high night temperature (HNT) under current and future climates. Here, we conducted field experiments to identify [CO2] responsiveness from a diverse indica panel comprising 194 genotypes under different planting geometries in 2016. Twenty-three different genotypes were tested under different planting geometries and e[CO2] using a free-air [CO2] enrichment facility in 2017. The most promising genotypes and positive and negative controls were tested under HNT and e[CO2] + HNT in 2018. [CO2] responsiveness, measured as a composite response index on different yield components, grain yield, and photosynthesis, revealed a strong relationship (R2 = 0.71) between low planting density and e[CO2]. The most promising genotypes revealed significantly lower (P < 0.001) impact of HNT in high [CO2] responsive (HCR) genotypes compared to the least [CO2] responsive genotype. [CO2] responsiveness was the major driver determining grain yield and related components in HCR genotypes with a negligible yield loss under HNT. A systematic investigation highlighted that active selection and breeding for [CO2] responsiveness can lead to maintained carbon balance and compensate for HNT-induced yield losses in rice and potentially other C3 crops under current and future warmer climates.


Assuntos
Dióxido de Carbono/efeitos adversos , Dióxido de Carbono/metabolismo , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/genética , Temperatura Alta/efeitos adversos , Oryza/crescimento & desenvolvimento , Oryza/genética , Oryza/metabolismo , Produtos Agrícolas/metabolismo , Variação Genética , Genótipo , Índia
9.
Am J Clin Nutr ; 115(1): 298-309, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34601579

RESUMO

BACKGROUND: Iodine intake in populations is usually assessed by measuring urinary iodine concentrations (UICs) in spot samples. Hot climate conditions may reduce urine volume, thus leading to overestimations of UIC and thereby masking inadequate iodine intake. OBJECTIVES: We investigated the effects of season on UICs in 2 populations exposed to high-temperature climates. METHODS: In this observational study, we examined women (18-49 years) in Tanzania (ncold = 206; nhot = 179) and South Africa (ncold = 157; nhot = 126) during cold and hot seasons. From each woman in both seasons, we obtained two 24-hour urine collections and 2 spot urine samples, as well as salt, water, and cow's milk samples. We measured the urine volume, UIC, and urinary creatinine concentration (UCC). The 24-hour urinary iodine excretion (UIE) was calculated and used to estimate the iodine intake. We used linear mixed-effects models to test for differences between seasons. RESULTS: In Tanzanian women, we observed no seasonal effect on the urine volume, 24-hour UIE, 24-hour UIC, spot UIC, spot UIC:UCC ratio, or salt iodine concentration. In South African women, the median 24-hour urine volume was 1.40 L (IQR, 0.96-2.05 L) in the winter and 15% lower in the summer (P < 0.001). The median 24-hour UIE was 184 µg/day (IQR, 109-267 µg/day) in the winter and 34% lower in the summer (P < 0.001), indicating a lower iodine intake. As a result, UICs did not significantly differ between seasons in 24-hour collections and spot samples, whereas the spot UIC:UCC ratio differed by 21% (P < 0.001) and reflected the lower iodine intake. In both study populations, the within- and between-person variabilities in urine volume, 24-hour UICs, and spot UICs were higher than the variability between seasons. CONCLUSIONS: Spot UIC may slightly overestimate the iodine intake in hot temperatures due to concentrated urine, and methods to correct for urine volume may be considered. Local seasonal differences in iodine intakes may also occur in some populations. This trial was registered at http://www.clinicaltrials.gov as NCT03215680.


Assuntos
Ingestão de Alimentos/fisiologia , Temperatura Alta/efeitos adversos , Iodo/urina , Adolescente , Adulto , Animais , Clima , Água Potável/química , Feminino , Humanos , Iodo/análise , Pessoa de Meia-Idade , Leite/química , Sais/química , Estações do Ano , África do Sul , Tanzânia , Adulto Jovem
10.
Clin Exp Pharmacol Physiol ; 49(3): 419-431, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34862806

RESUMO

Pain is responsible for inducing physical and mental stress, interfering negatively in patients' quality of life. Classic analgesic drugs, such as opioids and non-steroidal anti-inflammatory drugs, are known for their wide range of adverse effects, making it important to develop new drugs. Thus, this study aimed to analyse the action of the hybrid compound cis- (±) -acetate of 4-chloro-6- (naphthalene-1-yl) -tetrahydro-2h-pyran -2-yl) methyl2- (2- [2,6-dichlorophenylamine] phenyl (LS19) under acute nociceptive conditions, and deepened the understanding of the responsible mechanisms. Male Swiss mice were evaluated in the acetic acid-induced abdominal writhing, formalin, tail flick, capsaicin- and glutamate-induced nociception, thermal stimulation in animals injected with capsaicin and rotarod tests besides the acute and subchronic toxicological evaluation. The compound showed effect on the acetic acid-induced abdominal writhing, formalin (both phases), tail flick, thermal stimulation in animals injected with capsaicin and capsaicin-induced nociception tests. In the study of the mechanism of action was observed reversion of the antihyperalgesic effect of the compound from the previous intraperitoneal and intrathecal administration of naloxone, nor-binaltorphimine, naltrindole, methylnaltrexone, 7-nitroindazole, L-NAME, ODQ, glibenclamide on the tail flick test. In the thermal stimulation in animals injected with capsaicin, the compound showed antinociceptive effect by oral and intraplantar routes, besides to reducing the levels of TNF-α, IL-1ß and PGE2 in the paws previously administered with capsaicin. There were no signs of acute and subchronic intoxication with the compound. In summary, the compound LS19 presented spinal and local antihyperalgesic effect, demonstrating participation of the opioid/NO/cGMP/K+ ATP pathway and TRPV1 receptors and it demonstrated safety in its use in mice.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Dor/tratamento farmacológico , Piranos/farmacologia , Analgésicos/farmacologia , Animais , Anti-Inflamatórios não Esteroides/química , Capsaicina/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Ácido Glutâmico/toxicidade , Temperatura Alta/efeitos adversos , Humanos , Masculino , Camundongos , Dor/induzido quimicamente , Piranos/química
11.
World J Urol ; 40(1): 161-167, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34476596

RESUMO

PURPOSE: To objectively determine whether there is potential thermal tissue damage during Tm:YAG laser-based LUTS treatment. METHODS: Our experimental model was comprised of a prostatic resection trainer placed in a 37 °C water bath. In a hollowed-out central area simulating the urethral lumen, we placed a RigiFib 800 fibre, irrigation inflow regulated with a digital pump, and a type K thermocouple. A second thermocouple was inserted 0.5/1 cm adjacently and protected with an aluminum barrier to prevent it from urethral fluid. We investigated continuous and intermittent 120 W and 80 W laser application with various irrigation rates in eight measurement sessions lasting up to 14 min. Thermal measurements were recorded continuously and in real-time using MatLab. All experiments were repeated five times to balance out variations. RESULTS: Continuous laser application at 120 W and 125 ml/min caused a urethral ∆T of ~ 15 K and a parenchymal temperature increase of up to 7 K. With 50 ml/min irrigation, a urethral and parenchymal ∆T of 30 K and 15 K were reached, respectively. Subsequently and in absence of laser application, prostatic parenchyma needed over 16 min to reach baseline body temperature. At 80 W lower temperature increases were reached compared to similar irrigation but higher power. CONCLUSIONS: We showed that potentially harming temperatures can be reached, especially during high laser power and low irrigation. The heat generation can also be conveyed to the prostate parenchyma and deeper structures, potentially affecting the neurovascular bundles. Further clinical studies with intracorporal temperature measurement are necessary to further investigate this potentially harming surgical adverse effect.


Assuntos
Temperatura Alta/efeitos adversos , Lasers de Estado Sólido/efeitos adversos , Próstata , Prostatectomia/métodos , Humanos , Masculino , Modelos Teóricos
13.
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
14.
Plant Physiol ; 188(2): 1210-1228, 2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-34927688

RESUMO

Changes in environmental temperature affect multiple meiotic processes in flowering plants. Polyploid plants derived from whole-genome duplication (WGD) have enhanced genetic plasticity and tolerance to environmental stress but face challenges in organizing and segregating doubled chromosome sets. In this study, we investigated the impact of increased environmental temperature on male meiosis in autotetraploid Arabidopsis (Arabidopsis thaliana). Under low to mildly increased temperatures (5°C-28°C), irregular chromosome segregation universally occurred in synthetic autotetraploid Columbia-0 (Col-0). Similar meiotic lesions occurred in autotetraploid rice (Oryza sativa L.) and allotetraploid canola (Brassica napus cv Westar), but not in evolutionarily derived hexaploid wheat (Triticum aestivum). At extremely high temperatures, chromosome separation and tetrad formation became severely disordered due to univalent formation caused by the suppression of crossing-over. We found a strong correlation between tetravalent formation and successful chromosome pairing, both of which were negatively correlated with temperature elevation, suggesting that increased temperature interferes with crossing-over predominantly by impacting homolog pairing. We also showed that loading irregularities of axis proteins ASY1 and ASY4 co-localize on the chromosomes of the syn1 mutant and the heat-stressed diploid and autotetraploid Col-0, revealing that heat stress affects the lateral region of synaptonemal complex (SC) by impacting the stability of the chromosome axis. Moreover, we showed that chromosome axis and SC in autotetraploid Col-0 are more sensitive to increased temperature than those in diploid Arabidopsis. Taken together, our data provide evidence suggesting that WGD negatively affects the stability and thermal tolerance of meiotic recombination in newly synthetic autotetraploid Arabidopsis.


Assuntos
Arabidopsis/genética , Pareamento Cromossômico/fisiologia , Recombinação Homóloga/fisiologia , Temperatura Alta/efeitos adversos , Meiose/fisiologia , Oryza/genética , Poliploidia , Arabidopsis/fisiologia , Produtos Agrícolas/genética , Produtos Agrícolas/fisiologia , Variação Genética , Genótipo , Resposta ao Choque Térmico/genética , Resposta ao Choque Térmico/fisiologia , Oryza/fisiologia
15.
J Therm Biol ; 101: 103099, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34879917

RESUMO

Understanding the impact that heat stress has on critical life stages of an organism is essential when assessing population responses to extreme events. Heat stress may occur as repeated small-scale events or as a single prolonged event, which may cause different outcomes to the organism. Here, we subjected Helicoverpa punctigera (Wallengren) pupae to two temperatures (44.2 °C and 43 °C) and two exposure treatments - a single 3-h prolonged exposure prolonged and three repeated 1-h exposure period with 24 h recovery time between bouts - to assess the biological traits of individuals. The maximum temperatures were used as they were just below the critical thermal maximum (CTmax) 47.3 °C ± 0.3 °C of pupae for which they could survive exposure. Adults in the prolonged and repeated heat-stressed treatments had 1.70 and 3.34 more days to emergence and 1.57 and 3.30 days extended life span compared to those kept under a constant 25 °C temperature (control treatment). Both pre-oviposition and oviposition periods were extended in the heat-stressed groups. Fecundity in the prolonged and repeated heat-stressed females was reduced by 34.7% and 65.5% eggs in the 43 °C treatment group and by 94.3% and 93.6% eggs in the 44.2 °C treatment group compared to the control group. No eggs from females in either the prolonged and repeated heat-stress groups hatched. We establish that heat stress on pupae can influence the population dynamics of H. punctigera by reducing fecundity as well as extending the pre oviposition period, and affecting adult development. Also, as heat exposure on the parent generation resulted in no offspring production, it is critical to assess cross-generational responses to extreme heat stress.


Assuntos
Temperatura Alta/efeitos adversos , Mariposas/fisiologia , Animais , Feminino , Fertilidade , Resposta ao Choque Térmico , Longevidade , Masculino , Dinâmica Populacional , Pupa , Reprodução
16.
Nutrients ; 13(12)2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34959749

RESUMO

Using palatable fluids to enhance drinking in athletes who display insufficient compensatory hydration behaviour may mitigate the risks of hypohydration and performance deficits. However, it is unclear whether flavour can independently enhance fluid consumption. This study examined the effects of a colourless, artificially sweetened flavoured water (FW), without carbohydrates and with negligible amounts of sodium, compared to plain water (W) on fluid consumption in male collegiate basketball players in a practical game setting. Eighteen male basketball players (age 23.1 ± 1.3 years) played a 3v3 basketball small-sided game. The players were randomly assigned to consume either FW or W. Pre-game urine-specific gravity, fluid consumption, body mass, and hedonic taste perceptions were assessed. Basketball performance was analysed through notational analysis. Ratings of perceived exertion and thirst were recorded at pre-, post-game, and at each rest period. Heart rate was recorded throughout the gameplay. Despite significantly higher hedonic ratings for FW than W (6.78 ± 0.83 vs. 5.56 ± 1.33, p = 0.033, d = 1.36), there were no significant differences in fluid consumption (1083 ± 32 mL vs. 1421 ± 403 mL, p = 0.068, d = 0.92). Our result highlighted that using palatable fluids as a strategy to increase fluid consumption during high-intensity gameplay in the heat may not be effective if used without carbohydrates and electrolytes. Practitioners could consider both fluid palatability and composition in establishing a hydration plan for athletes.


Assuntos
Atletas/psicologia , Basquetebol/psicologia , Desidratação/prevenção & controle , Água Potável/administração & dosagem , Aromatizantes/administração & dosagem , Desempenho Atlético/fisiologia , Basquetebol/fisiologia , Comportamento de Ingestão de Líquido , Água Potável/química , Transtornos de Estresse por Calor/prevenção & controle , Temperatura Alta/efeitos adversos , Humanos , Masculino , Estado de Hidratação do Organismo/fisiologia , Filosofia , Percepção Gustatória , Universidades , Adulto Jovem
17.
Nutrients ; 13(12)2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34959861

RESUMO

The current study compared mouth swills containing carbohydrate (CHO), menthol (MEN) or a combination (BOTH) on 40 km cycling time trial (TT) performance in the heat (32 °C, 40% humidity, 1000 W radiant load) and investigates associated physiological (rectal temperature (Trec), heart rate (HR)) and subjective measures (thermal comfort (TC), thermal sensation (TS), thirst, oral cooling (OC) and RPE (legs and lungs)). Eight recreationally trained male cyclists (32 ± 9 y; height: 180.9 ± 7.0 cm; weight: 76.3 ± 10.4 kg) completed familiarisation and three experimental trials, swilling either MEN, CHO or BOTH at 10 km intervals (5, 15, 25, 35 km). The 40 km TT performance did not differ significantly between conditions (F2,14 = 0.343; p = 0.715; η2 = 0.047), yet post-hoc testing indicated small differences between MEN and CHO (d = 0.225) and MEN and BOTH (d = 0.275). Subjective measures (TC, TS, RPE) were significantly affected by distance but showed no significant differences between solutions. Within-subject analysis found significant interactions between solution and location upon OC intensity (F28,196 = 2.577; p < 0.001; η2 = 0.269). While solutions containing MEN resulted in a greater sensation of OC, solutions containing CHO experienced small improvements in TT performance. Stimulation of central CHO pathways during self-paced cycling TT in the heat may be of more importance to performance than perceptual cooling interventions. However, no detrimental effects are seen when interventions are combined.


Assuntos
Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Carboidratos da Dieta/administração & dosagem , Mentol/administração & dosagem , Antissépticos Bucais/administração & dosagem , Adulto , Temperatura Corporal/efeitos dos fármacos , Regulação da Temperatura Corporal/efeitos dos fármacos , Método Duplo-Cego , Frequência Cardíaca/efeitos dos fármacos , Temperatura Alta/efeitos adversos , Humanos , Umidade , Masculino , Boca , Antissépticos Bucais/química , Sensação Térmica/efeitos dos fármacos , Sede/efeitos dos fármacos
18.
Nat Commun ; 12(1): 7286, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34907184

RESUMO

Working in hot and potentially humid conditions creates health and well-being risks that will increase as the planet warms. It has been proposed that workers could adapt to increasing temperatures by moving labor from midday to cooler hours. Here, we use reanalysis data to show that in the current climate approximately 30% of global heavy labor losses in the workday could be recovered by moving labor from the hottest hours of the day. However, we show that this particular workshift adaptation potential is lost at a rate of about 2% per degree of global warming as early morning heat exposure rises to unsafe levels for continuous work, with worker productivity losses accelerating under higher warming levels. These findings emphasize the importance of finding alternative adaptation mechanisms to keep workers safe, as well as the importance of limiting global warming.


Assuntos
Adaptação Fisiológica/fisiologia , Aquecimento Global , Recursos Humanos/tendências , Mudança Climática , Eficiência , Previsões , Temperatura Alta/efeitos adversos , Humanos , Umidade/efeitos adversos , Exposição Ocupacional/efeitos adversos , Jornada de Trabalho em Turnos
19.
Sci Rep ; 11(1): 23014, 2021 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-34836993

RESUMO

Consumption of very hot beverages and foods increases the incidence of oral and esophageal cancer but the mechanisms are not known and the critical temperature is not well defined. We realized a study with exfoliated cells from the oral cavity of individuals (n = 73) that live in an area in Iran which has the highest incidence of EC worldwide. Consumption of beverages at very high temperatures is a characteristic feature of this population. We analyzed biomarkers which are (i) indicative for genetic instability (micronuclei that are formed as a consequence of chromosomal damage, nuclear buds which are a consequence of gene amplifications and binucleated cells which reflect mitotic disturbances), (ii) markers that reflect cytotoxic effects (condensed chromatin, karyorrhectic, karyolitic and pyknotic cells), (iii) furthermore, we determined the number of basal cells which is indicative for the regenerative capacity of the buccal mucosa. The impact of the drinking temperature on the frequencies of these parameters was monitored with thermometers. We found no evidence for induction of genetic damage but an increase of the cytotoxic effects with the temperature was evident. This effect was paralleled by an increase of the cell division rate of the mucosa which was observed when the temperature exceeded 60 °C. Our findings indicate that cancer in the upper digestive tract in drinkers of very hot beverages is not caused by damage of the genetic material but by an increase of the cell division rate as a consequence of cytotoxic effects which take place at temperatures over 60 °C. It is known from earlier experiments with rodents that increased cell divisions lead to tumor promotion in the esophagus. Our findings provide a mechanistic explanation and indicate that increased cancer risks can be expected when the drinking temperature of beverages exceeds 60 °C.


Assuntos
Bebidas/efeitos adversos , Dano ao DNA , Neoplasias Esofágicas/etiologia , Temperatura Alta/efeitos adversos , Mucosa Bucal/patologia , Neoplasias Bucais/etiologia , Adulto , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Feminino , Humanos , Incidência , Irã (Geográfico)/epidemiologia , Masculino , Mitose , Mucosa Bucal/metabolismo , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Fatores de Risco , Adulto Jovem
20.
Biol Open ; 10(11)2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34787304

RESUMO

The protein composition of the cestode Schistocephalus solidus was measured in an experiment simulating the trophic transmission of the parasite from a cold-blooded to a warm-blooded host. The first hour of host colonisation was studied in a model experiment, in which sticklebacks Gasterosteus aculeatus infected with S. solidus were heated at 40°C for 1 h. As a result, a decrease in the content of one tegument protein was detected in the plerocercoids of S. solidus. Sexual maturation of the parasites was initiated in an experiment where S. solidus larvae were taken from fish and cultured in vitro at 40°C for 48 h. Temperature-independent changes in the parasite proteome were investigated by incubating plerocercoids at 22°C for 48 h in culture medium. Analysis of the proteome allowed us to distinguish the temperature-induced genes of S. solidus, as well as to specify the molecular markers of the plerocercoid and adult worms. The main conclusion of the study is that the key enzymes of long-term metabolic changes (glycogen consumption, protein production, etc.) in parasites during colonisation of a warm-blooded host are induced by temperature.


Assuntos
Doenças dos Peixes/parasitologia , Interações Hospedeiro-Parasita , Temperatura Alta/efeitos adversos , Proteoma/metabolismo , Smegmamorpha/parasitologia , Animais , Cestoides
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