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1.
Braz. j. biol ; 84: e253084, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1345551

RESUMEN

Abstract Repeatedly frying process of dietary edible oil has a potential role in the generation of free radicals. Therefore, questions have always been raised as to whether, there is an efficient and economical method to reduce the harmful effects of repeated use of frying edible oil. Since hibiscus has been stated to have a wide variety of therapeutic effects, it was important to investigate its properties against harmful effects of free radicals. The current study aspires to find out whether irradiated powder of hibiscus has a protective role against adverse effects of repeated use of frying edible oil. Thirty-five adult male albino rats were equally assigned into five groups. First group"G1" was fed with normal diet as control group, meanwhile, group"G2" the diet mixed with fresh oil, "G3" diet mixed with repeatedly frying oil only, "G4" diet mixed with frying oil treated with hibiscus and "G5" diet mixed with frying oil treated with irradiated hibiscus. Feeding duration was six weeks. Fatty acid analyses of oil as well as peroxide values were determined. Blood and liver samples were collected for biochemical analyses as well as histological study. Repeatedly heated cooked oil has significant increases in peroxide value, acid value, free fatty acid and both conjugated diene and triene compared with repeatedly frying oil treated with hibiscus. Also there are significant increases in cholesterol and triglyceride and impaired in liver functions in "G3"compared with others. In addition, relative to the hibiscus groups, there is a substantial reduction in oxygen consumption in "G3". Both hibiscus as well as irradiated hibiscus attract attention in order to play a vital and economical role against harmful effects of frequent use of frying edible oil on some biological functions but, irradiated hibiscus was more effective.


Resumo O processo de fritura repetida de óleo comestível da dieta tem papel potencial na geração de radicais livres que podem ter efeitos prejudiciais em algumas funções biológicas. Portanto, sempre se questionou se existe uma maneira eficiente e econômica de prevenir ou pelo menos reduzir os efeitos nocivos do uso repetido de óleo comestível para fritar. Como o hibisco tem ampla variedade de efeitos terapêuticos, foi importante investigar suas propriedades como agente antioxidante contra os efeitos nocivos dos radicais livres. O presente estudo pretende descobrir se o pó irradiado de hibisco tem papel protetor contra os efeitos adversos do uso repetido de óleo comestível para fritar. Trinta e cinco ratos albinos machos adultos foram divididos igualmente em cinco grupos. O primeiro grupo "G1" foi alimentado com dieta normal como grupo controle, enquanto o grupo "G2" dieta misturada com óleo fresco, dieta "G3" misturada com óleo de fritura repetida, dieta "G4" misturada com óleo de fritura tratada com hibisco e dieta "G5" misturada com óleo de fritura tratada com hibisco irradiado. A duração da alimentação foi de seis semanas. Foram determinadas as análises de ácidos graxos de óleo, bem como os valores de peróxidos. Amostras de sangue e fígado foram coletadas para análises bioquímicas e estudo histológico. O óleo cozido repetidamente aquecido tem aumentos significativos no valor de peróxido, valor de ácido, ácido graxo livre e dieno e trieno conjugados em comparação com óleo de fritura repetidamente tratado com hibisco. Também há aumentos significativos no colesterol e triglicérides e comprometimento das funções hepáticas no "G3" em comparação com outros. Além disso, em relação aos grupos de hibiscos, há uma redução substancial no consumo de oxigênio no "G3". Tanto o hibisco como o hibisco irradiado chamam atenção por desempenhar papel vital e econômico contra os efeitos nocivos do uso frequente de óleo comestível para fritar em algumas funções biológicas, mas o hibisco irradiado foi mais eficaz.


Asunto(s)
Animales , Ratas , Hibiscus , Aceites Vegetales/farmacología , Colesterol , Culinaria , Calor
2.
Sensors (Basel) ; 23(2)2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36679808

RESUMEN

The production of thermoluminescence (TL) dosimeters fabricated from B2O3-CaF2-Al2O3-SiO2 doped with Cu and Pr for use in diagnostic radiology is the main goal of this research. The TL samples were synthesized via the melt-quench technique processed by melting the mixture at 1200 °C for 1 h, and, after cooling, the sample thus created was divided into two samples and retreated by heating for 2 h (referred to as TLV30) and for 15 h (referred to as TLV17). SEM and EDS analyses were performed on the TL samples to confirm the preparation process and to investigate the effects of irradiation dosimetry on the TL samples. Furthermore, the TL samples were irradiated with γ-rays using a 450 Ci 137Cs irradiator and variable X-ray beams (5-70 mGy). Two important diagnostic radiology applications were considered: CT (6-24 mGy) and mammography (2.72-10.8 mGy). Important dosimetric properties, such as the glow curves, reproducibility, dose-response linearity, energy dependence, minimum dose detectability and fading, were investigated for the synthetized samples (TLV17 and TLV30), the results of which were compared with the Harshaw TLD-100. The TLV17 dosimeter showed higher sensitivity than TLV30 in all applied irradiation procedures. The dose-response linearity coefficients of determination R2 for TLV17 were higher than TLD-100 and TLV30 in some applications and were almost equal in others. The reproducibility results of TLV17, TLV30 and TLD-100 were less than 5%, which is acceptable. On the other hand, the results of the fading investigations showed that, in general, TLV17 showed less fading than TLV30. Both samples showed a significant decrease in this regard after the first day, and then the signal variation became essentially stable though with a slight decrease until the eighth day. Therefore, it is recommended to read the TL dosimeters after 24 h, as with TLD-100. The SEM images confirmed the existence of crystallization, whilst the EDS spectra confirmed the presence of the elements used for preparation. Furthermore, we noticed that TLV17 had grown dense crystals that were larger in size compared to those of TLV30, which explains the higher sensitivity in TLV17. Overall, despite the fading, TLV17 showed greater radiation sensitivity and dose-response linearity compared with TLD-100. The synthetized TL samples showed their suitability for use as dosimeters in diagnostic radiology radiation dosimetry.


Asunto(s)
Radiología , Silicio , Dosímetros de Radiación , Aluminio , Calcio , Calor , Dióxido de Silicio , Reproducibilidad de los Resultados , Boratos , Dosimetría Termoluminiscente , Radiometría
3.
Molecules ; 28(2)2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36677823

RESUMEN

Coatings of metal specimens are known to have an impact on hydrogen gettering (hydrogen absorption). The coating can have one or more functions, such as enhancing gettering, preventing gettering and/or preventing oxidation of the metal substrate. It is known that contaminants and surface texture can impact hydrogen gettering/absorption performance, but has not previously been thoroughly explored. This study evaluated the role of different post-plating heat treatments of nickel-plated zircaloy-4 getters (NPGs) and the role of the heat treatments on gettering rates, surface composition and texture. Nickel plating is applied to prevent oxidation of the Zircaloy-4 surface and also enhances gettering. The nickel plating must be heat treated before desirable gettering can occur. Our NPG getters with historically known satisfying performance were pre-heat treated in air followed by activation heat treatment in a vacuum at a higher temperature. In this study, we were interested in finding out if both heat treatment steps were necessary to obtain a desirable gettering performance, or if one step could be omitted. XPS analysis showed that if the nickel surface is not heat treated before bonding the nickel to the zirconium in the activation step, there will be carbon contaminants on the surface, which significantly reduces gettering. We studied the texture of Zircaloy-4 using SEM/EBSD to compare NPGs with both heat treatment steps with NPGs that had no post-plating heat treatment to learn if the degree of cold work could be impacted by the heat treatment steps. We did not observe any differences in texture between them. We measured gettering rates of both pretreated and activated NPGs and NPGs that had been activated without first being pre-heat treated. We found that the NPGs without the first post-plating heating step had up to a seven times slower gettering rate and obtained higher plateau pressures due to the contaminated surface. Thus, the pre-heat treatment in air before activation is necessary to avoid slower gettering rates and higher plateau pressures.


Asunto(s)
Galactosilceramidas , Níquel , Níquel/química , Calor , Frío
4.
Artículo en Inglés | MEDLINE | ID: mdl-36674069

RESUMEN

The capacity for adaptation to climate change is limited, and the elderly rank high among the most exposed population groups. To date, few studies have addressed the issue of heat adaptation, and little is known about the long-term effects of exposure to heat. One indicator that allows the ascertainment of a population's level of adaptation to heat is the minimum mortality temperature (MMT), which links temperature and daily mortality. The aim of this study was to ascertain, firstly, adaptation to heat among persons aged ≥ 65 years across the period 1983 to 2018 through analysis of the MMT; and secondly, the trend in such adaptation to heat over time with respect to the total population. A retrospective longitudinal ecological time series study was conducted, using data on daily mortality and maximum daily temperature across the study period. Over time, the MMT was highest among elderly people, with a value of 28.6 °C (95%CI 28.3-28.9) versus 28.2 °C (95%CI 27.83-28.51) for the total population, though this difference was not statistically significant. A total of 62% of Spanish provinces included populations of elderly people that had adapted to heat during the study period. In general, elderly persons' level of adaptation registered an average value of 0.11 (°C/decade).


Asunto(s)
Termotolerancia , Anciano , Humanos , España/epidemiología , Estudios Retrospectivos , Temperatura , Calor , Mortalidad
5.
Artículo en Inglés | MEDLINE | ID: mdl-36674088

RESUMEN

The aim of this article is to assess the potential impact of inorganic salt hydrates used as PCM material in solar installations on the environment and human health and to assess the society's approach to this technology. The properties of salt are discussed in two ways: first, by analyzing the environmental and health problems caused by chemical hazards on the basis of the available material safety data sheets. Secondly, by analyzing the potential disadvantages of salt hydrates in terms of environmental hazards based on the results of experimental studies available in the literature. Then, using questionnaires, the public approach to solar installations with a built-in converter containing salt hydrates is assessed. Disodium hydrogen phosphate dodecahydrate turned out to be the most prospective salt in terms of environmental, thermophysical, and economic properties for use in solar installations. Understanding the attitudes of the local community toward technologies using inorganic salt hydrates will enable appropriate action to be taken in the future to promote their development. Surveys have shown great public concern about their impact on the environment and human health. In this regard, it is necessary to implement information and promotion activities.


Asunto(s)
Calor , Humanos , Estudios Prospectivos
6.
Nutrients ; 15(1)2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36615873

RESUMEN

To determine the effects of heat acclimation on gastrointestinal (GI) damage and the gastric emptying (GE) rate following endurance exercise in a hot environment. Fifteen healthy men were divided into two groups: endurance training in hot (HOT, 35 °C, n = 8) or cool (COOL, 18 °C, n = 7) environment. All subjects completed 10 days of endurance training (eight sessions of 60 min continuous exercise at 50% of the maximal oxygen uptake (V·O2max). Subjects completed a heat stress exercise tests (HST, 60 min exercise at 60% V·O2max) to evaluate the plasma intestinal fatty acid-binding protein (I-FABP) level and the GE rate following endurance exercise in a hot environment (35 °C) before (pre-HST) and after (post-HST) the training period. We assessed the GE rate using the 13C-sodium acetate breath test. The core temperature during post-HST exercise decreased significantly in the HOT group compared to the pre-HST (p = 0.004) but not in the COOL group. Both the HOT and COOL groups showed exercise-induced plasma I-FABP elevations in the pre-HST (p = 0.002). Both groups had significantly attenuated exercise-induced I-FABP elevation in the post-HST. However, the reduction of exercise-induced I-FABP elevation was not different significantly between both groups. GE rate following HST did not change between pre- and post-HST in both groups, with no significant difference between two groups in the post-HST. Ten days of endurance training in a hot environment improved thermoregulation, whereas exercise-induced GI damage and delay of GE rate were not further attenuated compared with training in a cool environment.


Asunto(s)
Ejercicio Físico , Calor , Masculino , Humanos , Ejercicio Físico/fisiología , Regulación de la Temperatura Corporal , Terapia por Ejercicio , Aclimatación , Temperatura Corporal/fisiología
7.
BMC Plant Biol ; 23(1): 7, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36600201

RESUMEN

BACKGROUND: Heat stress has adverse effects on the growth and reproduction of plants. Zygophyllum xanthoxylum, a typical xerophyte, is a dominant species in the desert where summer temperatures are around 40 °C. However, the mechanism underlying the thermotolerance of Z. xanthoxylum remained unclear. RESULTS: Here, we characterized the acclimation of Z. xanthoxylum to heat using a combination of physiological measurements and transcriptional profiles under treatments at 40 °C and 45 °C, respectively. Strikingly, moderate high temperature (40 °C) led to an increase in photosynthetic capacity and superior plant performance, whereas severe high temperature (45 °C) was accompanied by reduced photosynthetic capacity and inhibited growth. Transcriptome profiling indicated that the differentially expressed genes (DEGs) were related to transcription factor activity, protein folding and photosynthesis under heat conditions. Furthermore, numerous genes encoding heat transcription shock factors (HSFs) and heat shock proteins (HSPs) were significantly up-regulated under heat treatments, which were correlated with thermotolerance of Z. xanthoxylum. Interestingly, the up-regulation of PSI and PSII genes and the down-regulation of chlorophyll catabolism genes likely contribute to improving plant performance of Z. xanthoxylum under moderate high temperature. CONCLUSIONS: We identified key genes associated with of thermotolerance and growth in Z. xanthoxylum, which provide significant insights into the regulatory mechanisms of thermotolerance and growth regulation in Z. xanthoxylum under high temperature conditions.


Asunto(s)
Termotolerancia , Zanthoxylum , Zygophyllum , Termotolerancia/genética , Sodio/metabolismo , Zygophyllum/genética , Zygophyllum/metabolismo , Zanthoxylum/genética , Transcriptoma , Perfilación de la Expresión Génica , Respuesta al Choque Térmico/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Calor , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas
8.
BMC Pulm Med ; 23(1): 3, 2023 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-36600236

RESUMEN

BACKGROUND: Although there are currently alternative treatments to the long-term use of oral corticosteroids (OCS) in severe asthma, recent studies show excessive use depending on geography and differences in medical practice. The objective of the study was to describe the differences in OCS use for severe asthma across the Spanish geography. METHODS: This is a real-world study using existing databases (year 2019): longitudinal patient database (EMR), based on electronic medical records, and database of pharmacological consumption (Sell-in) in basic healthcare areas. With EMR, the percentage of OCS prescriptions corresponding to patients with severe asthma (ICD-9 "asthma" and prescription of biological treatment and/or high dose of inhaled corticosteroids/long-acting inhaled ß2 agonists) was calculated. This percentage was transferred to the OCS consumption of each basic healthcare area as reported in the Sell-in database and a national heat map was created. The estimation of OCS use in patients with severe asthma per 100,000 inhabitants for each region was calculated by grouping basic healthcare areas and the mean OCS use per patient for different regions in Spain was also estimated. RESULTS: Patients with severe asthma in Spain were mostly female (69.6%), with a mean age (SD) of 57.6 years (18.01). Median time (Pc25-Pc75) since asthma diagnosis was 83.1 months (34.65-131.56). Of all patients with OCS prescriptions in 2019 identified in EMR, 4.4% corresponded to patients with severe asthma. Regions with the highest OCS use were Asturias, Andalucía, and Galicia, whereas those with the lowest use were Navarra, Baleares, Madrid and País Vasco. The mean OCS use per patient with severe asthma in 2019 throughout Spain was 1099.85 mg per patient, ranging from 782.99 mg in Navarra to 1432.64 in Asturias. CONCLUSIONS: There are geographical differences between Spanish regions with respect to the use of OCS in patients with severe asthma. The national mean consumption of OCS per patient with severe asthma and year is above the limits that indicate good asthma control.


Asunto(s)
Antiasmáticos , Asma , Humanos , Femenino , Persona de Mediana Edad , Masculino , España/epidemiología , Calor , Asma/tratamiento farmacológico , Asma/epidemiología , Asma/diagnóstico , Corticoesteroides/uso terapéutico , Prescripciones , Antiasmáticos/uso terapéutico
9.
Int J Hyperthermia ; 40(1): 2122597, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36642421

RESUMEN

OBJECTIVES: The outcome of balloon-based atherosclerosis thermoplasty is closely related to the temperature/stress distribution during the treatment. For precise prediction of a required thermal lesion in the heterogeneous and thin atherosclerotic vessel, a numerical model incorporating heat-induced tissue expansion or shrinkage and the strain caused by balloon dilation is necessary. METHODS: A fully coupled thermal-electrical-structural new model was established. The model features a heterogeneous structure including eccentric plaque, healthy artery and surrounding tissue. Tissue expansion/shrinkage and hyperelasticity material model were taken into consideration. Different heating strategies and plaque mechanical properties were investigated. The temperature distribution was compared with the traditional thermal-electrical coupled model. The possibility of thermoplasty treatment using balloons with different sizes was also explored. RESULTS: The temperature, the electrical intensity and the stress during the thermoplasty were obtained. Lower stress was found in the heating region where tissue shrinkage occurred. The ablation depth was predicted to be ∼0.42 mm larger without coupling the biomechanical influence. The mechanical properties and input condition significantly affect the temperature and stress distribution considering the small dimensions of the tissue. Besides, with a 12.5% reduction of balloon diameter, the largest Von Mises stress decreases by 25.4%. CONCLUSIONS: It is confirmed that a coupled thermal-electrical-structural model is needed for precise temperature prediction in the balloon-based thermoplasty of the heterogeneous and thin tissue. The model presented may help with future development of optimized treatment planning considering both ablation depth and minimum stress.


Asunto(s)
Aterosclerosis , Calor , Humanos , Temperatura
10.
Sci Rep ; 13(1): 36, 2023 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-36593276

RESUMEN

Characterizing the integrity of ground anchors is essential for examining their usability in the maintenance of soil structure. However, the lift-off test, which is generally used for this purpose, has limitations when applied to covering all installed ground anchors. The objective of this study is to assess the possibility of using infrared thermography to measure the residual stress in ground anchors as a noncontact technique that bypasses the disadvantages associated with existing techniques. A preliminary experiment is performed to determine the exact emissivity of the tested materials. Both passive and active methods, as representative techniques in infrared thermography, are applied. In the large-scale experiment, infrared images of four installed strands with growing stress in the range of 0-400 kPa at 100 kPa intervals are used in the passive method of measurement. For the active method, these same stress ranges are applied to a heated anchor head using a UTM machine. The results of the passive method show that the temperature increased and decreased according to load and unload steps. Values for the cooling rate index are deduced through the active method results, and reliable behavior are observed at 10 and 15 min. The number of pixels with huge temperature changes also changed with the loading step in both passive and active methods. This study demonstrates that infrared thermography is a suitable alternative method for assessing the residual stress in ground anchors as a type of noncontact technique.


Asunto(s)
Frío , Termografía , Termografía/métodos , Temperatura , Calor , Suelo , Rayos Infrarrojos
11.
Sci Rep ; 13(1): 35, 2023 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-36593354

RESUMEN

Study of the frequency and magnitude of climate extremes as the world warms is of utmost importance, especially separating the influence of natural and anthropogenic forcing factors. Record-breaking temperature and precipitation events have been studied using event-attribution techniques. Here, we provide spatial and temporal observation-based analyses of the role of natural and anthropogenic factors, using state-of-the-art time series methods. We show that the risk from extreme temperature and rainfall events has severely increased for most regions worldwide. In some areas the probabilities of occurrence of extreme temperatures and precipitation have increased at least fivefold and twofold, respectively. Anthropogenic forcing has been the main driver of such increases and its effects amplify those of natural forcing. We also identify risk hotspots defined as regions for which increased risk of extreme events and high exposure in terms of either high Gross Domestic Product (GDP) or large population are both present. For the year 2018, increased anthropogenic forcings are mostly responsible for increased risk to extreme temperature/precipitation affecting 94%/72% of global population and 97%/76% of global GDP relative to the baseline period 1961-1990.


Asunto(s)
Cambio Climático , Clima , Temperatura , Calor , Probabilidad
12.
Sci Rep ; 13(1): 1362, 2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36693895

RESUMEN

Drug treatment of limb frostbite injuries is complicated due to the poor delivery of medications to affected tissues. External rewarming of the frostbitten area is risky and does not always result in positive outcomes because the dilatation of superficial vessels with constricted deep vessels can lead to irreversible damage, necrosis, and amputation. One of the techniques to restore perfusion of deep vessels in an affected extremity is rewarming with low-power microwave radiation in a specially designed metal chamber. Below are findings following treatment of 14 volunteers with this technique in 2 Tomsk hospitals during winters of 2018-2021. It is demonstrated that timely, i.e. in the early reactive period, application of microwave radiation and appropriate supportive drug treatment results in positive amputation-free outcomes. The key requirement is prompt thermal insulation of the trauma and no prior exposure to external heat sources.


Asunto(s)
Recalentamiento , Humanos , Microondas/uso terapéutico , Calor , Extremidades
13.
Sensors (Basel) ; 23(1)2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36617053

RESUMEN

Thermostats operate alongside intelligent home automation systems for ensuring both the comfort of the occupants as well as the responsible use of energy. The effectiveness of such solutions relies on the ability of the adopted control methodology to respond to changes in the surrounding environment. In this regard, process disturbances such as severe wind or fluctuating ambient temperatures must be taken into account. The present paper proposes a new approach for estimating the heat transfer of residential buildings by employing a lumped parameter thermal analysis model. Various control strategies are adopted and tuned into a virtual environment. The knowledge gained is generalized by means of a long short-term memory (LSTM) neural network. Laboratory scale experiments are provided to prove the given concepts. The results achieved highlight the efficiency of the implemented temperature controller in terms of overshoot and energy consumption.


Asunto(s)
Conservación de los Recursos Energéticos , Redes Neurales de la Computación , Temperatura , Automatización , Calor
14.
Biol Lett ; 19(1): 20220495, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36651031

RESUMEN

We identify for wild, free-living short-beaked echidnas (Tachyglossus aculeatus) a novel evaporative window, along with thermal windows, and demonstrate the insulating properties of the spines, using infrared thermography. The moist tip of their beak, with an underlying blood sinus, functions as a wet bulb globe thermometer, maximizing evaporative heat loss via an evaporative window. The ventral surface and insides of the legs are poorly insulated sites that act as postural thermal windows, while the spines provide flexible insulation (depending on piloerection). These avenues of heat exchange likely contribute to the higher-than-expected thermal tolerance of this species. Our study highlights how technological advances that allow for non-contact measurement of thermal variables allow us to better understand the physiological capacity of animals in their natural environment.


Asunto(s)
Tachyglossidae , Animales , Tachyglossidae/fisiología , Ambiente , Regulación de la Temperatura Corporal , Calor , Pico
15.
Sci Rep ; 13(1): 922, 2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-36650176

RESUMEN

This study compared the relative risks of heat days on mortalities by vulnerable groups (elderly, single-person households, less-educated) in the past decade (1999-2008) and the recent decade (2009-2018) in four cities, Seoul, Incheon, Daegu, and Gwangju, in Korea. It has been known that the health impacts of heatwaves have gradually decreased over time due to socio-economic development, climate adaptation, and acclimatization. Contrary to general perception, we found that the recent relative risk of mortality caused by heat days has increased among vulnerable groups. It may associate with recent increasing trends of severe heat days due to climate change. The increasing relative risk was more significant in single-person households and less-educated groups than in the elderly. It implies that the impacts of climate change-induced severe heat days have been and will be concentrated on vulnerable groups. It suggests that social polarization and social isolation should be addressed to reduce heatwave impacts. Furthermore, this study shows the necessity of customized heatwave policies, which consider the characteristics of vulnerable groups.


Asunto(s)
Cambio Climático , Calor , Humanos , Anciano , Temperatura , Corea (Geográfico) , Ciudades , Seúl
16.
PeerJ ; 11: e14640, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36650834

RESUMEN

Background: Insufficient thermal ablation can accelerate malignant behaviors and metastases in some solid tumors, and epithelial-mesenchymal transition (EMT) and autophagy are involved in tumor metastasis. It has been found that TGF-ß2 which belongs to the family of transforming growth factors often associated with cancer cell invasiveness and EMT. However, whether the interactions between autophagy and TGF-ß2 induce EMT in breast cancer (BC) cells following insufficient microwave ablation (MWA) remains unclear. Methods: BC cells were treated with sublethal heat treatment to simulate insufficient MWA, and the effects of heat treatment on the BC cell phenotypes were explored. CCK-8, colony formation, flow cytometry, Transwell, and wound healing assays were performed to evaluate the influence of sublethal heat treatment on the proliferation, apoptosis, invasion, and migration of BC cells. Western blotting, real-time quantitative PCR, immunofluorescence, and transmission electron microscopy were carried out to determine the changes in markers associated with autophagy and EMT following sublethal heat treatment. Results: Results showed that heat treatment promoted the proliferation of surviving BC cells, which was accompanied by autophagy induction. Heat treatment-induced autophagy up-regulated TGF-ß2/Smad2 signaling and promoted EMT phenotype, thereby enhancing BC cells' migration and invasion abilities. An increase or decrease of TGF-ß2 expression resulted in the potentiation and suppression of autophagy, as well as the enhancement and abatement of EMT. Autophagy inhibitors facilitated apoptosis and repressed proliferation of BC cells in vitro, and thwarted BC cell tumor growth and pulmonary metastasis in vivo. Conclusion: Heat treatment-induced autophagy promoted invasion and metastasis via TGF-ß2/Smad2-mediated EMTs. Suppressing autophagy may be a suitable strategy for overcoming the progression and metastasis of residual BC cells following insufficient MWA.


Asunto(s)
Neoplasias Pulmonares , Factor de Crecimiento Transformador beta2 , Humanos , Movimiento Celular , Factor de Crecimiento Transformador beta2/genética , Transición Epitelial-Mesenquimal , Calor , Neoplasias Pulmonares/patología , Invasividad Neoplásica , Autofagia/genética
17.
Artículo en Inglés | MEDLINE | ID: mdl-36673928

RESUMEN

This research proposes a collection of urban heat island (UHI) risk indicators under four UHI risk components: hazard, exposure, sensitivity, and adaptive capacity. There are 46 UHI risk indicators linked to three pillars of sustainability: social equity, economic viability, and environmental protection. In this study, the UHI risk indicators were first validated by experts to determine their relevancy and subsequently applied to randomly sampled dwellers of Thailand's capital Bangkok. The UHI indicators were further validated with confirmatory factor analysis to determine the factor loadings (0-1) and reliability. Under the hazard component, the percentage of days when the daily minimum temperature is less than the 10th percentile exhibited the highest indicator-level factor loading (0.915). Vehicular traffic was the UHI exposure indicator with the highest factor loading (0.923), and the proportion of green space to build environment was the UHI sensitivity indicator with the highest factor loading (0.910). For the UHI adaptive capacity component, the highest factor loading (0.910) belonged to government policy and action. To effectively mitigate UHI impacts, greater emphasis should be placed on the indicators with highest factor loadings. Essentially, this research is the first to use statistical structural equation modeling to validate UHI indicators.


Asunto(s)
Calor , Políticas , Ciudades , Reproducibilidad de los Resultados , Tailandia
18.
Methods Mol Biol ; 2617: 189-200, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36656525

RESUMEN

Inclusion bodies (IB) are dense insoluble aggregates of mostly misfolded polypeptides that usually result from recombinant protein overexpression. IB formation has been observed in protein expression systems such as E. coli, yeast, and higher eukaryotes. To recover soluble recombinant proteins in their native state, IB are commonly first solubilized with a high concentration of denaturant. This is followed by concurrent denaturant removal or reduction and a transition into a refolding-favorable chemical environment to facilitate the refolding of solubilized protein to its native state. Due to the high concentration of denaturant used, conventional refolding approaches can result in dilute products and are buffer inefficient. To circumvent the limitations of conventional refolding approaches, a temperature-based refolding approach which combines a low concentration of denaturant (0.5 M guanidine hydrochloride, GdnHCl) with a high temperature (95 °C) during solubilization was proposed. In this chapter, we describe a temperature-based refolding approach for the recovery of core streptavidin (cSAV) from IB. Through the temperature-based approach, intensification was achieved through the elimination of a concentration step which would be required by a dilution approach and through a reduction in buffer volumes required for dilution or denaturant removal. High-temperature treatment during solubilization may have also resulted in the denaturation and aggregation of undesired host-cell proteins, which could then be removed through a centrifugation step resulting in refolded cSAV of high purity without the need for column purification. Refolded cSAV was characterized by biotin-binding assay and SDS-PAGE, while purity was determined by RP-HPLC.


Asunto(s)
Escherichia coli , Calor , Temperatura , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes/química , Cuerpos de Inclusión/metabolismo , Pliegue de Proteína , Replegamiento Proteico
19.
Carbohydr Polym ; 303: 120477, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36657850

RESUMEN

The effects of starch granule-associated surface lipids removal on hull-less barley starch structure formed by heat-moisture treatment were investigated. Removing surface lipids made the peak at 2θ of 13° disappear and resulted in higher lamellar peak intensity after harsh treatment and a lower reduction in mass fractal dimension (from 2.49 to 2.43) and radius of gyration (from 24.3 to 24.0) when temperature increased from 100 to 120 °C at 20 % moisture. Treatment at 25 % moisture and 120 °C decreased relative crystallinity (from 15.73 % to 7.43 %) and Gaussian peak area (from 646.7 to 137.7) of native starch, and decreased relative crystallinity (from 14.24 % to 12.56 %) and Gaussian peak area (from 604.1 to 539.6) for starch without surface lipids. Different trends of change in lamellar thickness, linear crystallinity, peak temperatures, and enthalpy of gelatinization were observed among modified starches with increasing temperature and/or moisture content. These results demonstrate that removing surface lipids changes structure of heat-moisture treated starch.


Asunto(s)
Hordeum , Almidón , Almidón/química , Calor , Temperatura , Lípidos
20.
Genet Sel Evol ; 55(1): 4, 2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36658500

RESUMEN

BACKGROUND: Heat stress negatively influences cattle welfare, health and productivity. To cope with the forecasted increases in temperature and heat waves frequency, identifying high-producing animals that are tolerant to heat is of capital importance to maintain milk production. This study, based on the joint analysis of on-farm performance and weather data, had two objectives: (1) to determine the response in production performances (milk, fat and protein yields, fat and protein contents) and udder health (somatic cell score) to temperature-humidity index (THI) variations in Montbeliarde cows, and (2) to estimate the interactions between genotype and THI, to enable the identification of the most adapted animals for facing the expected increases in temperature. RESULTS: Test-day records from first and second lactations from 2016 to 2020 were associated with the average THI during the three days before the test-day record. In total, 446,717 test-day records from 55,650 cows in first lactation and 457,516 test-day records from 58,229 cows in second lactation were analysed. The optimal THI was below 55 (i.e. ~ 12-13 °C) for all traits. Individual responses to THI were estimated by random regression models, which also included individual responses to days in milk. Regardless of the stage of lactation, genetic correlations along the THI gradient were above 0.80, which suggests that genotype-by-THI interactions were weak for production and udder health traits. Nevertheless, a variability in the individual slope of decay could be highlighted at high THI. The genetic correlation between production level at moderate THI and the slope at high THI was negative, while for somatic cell score, it was positive, indicating that heat stress amplifies the susceptibility to mastitis. CONCLUSIONS: The optimal THI for French Montbeliarde cows is below 55 for production and udder health traits. Genetic-by-THI interactions are weak in French Montbeliarde cows for production and udder health traits, but not all animals react in the same way to high temperatures. Even if there is little room for improvement, using a heat tolerance index in cattle selection would be relevant to anticipate the expected increases in temperature. Further investigations are needed to interpret this variability on production traits. However, the current selection for mastitis resistance seems appropriate to adapt cattle to rising temperatures.


Asunto(s)
Trastornos de Estrés por Calor , Leche , Femenino , Bovinos/genética , Animales , Humedad , Leche/metabolismo , Temperatura , Glándulas Mamarias Animales , Lactancia/genética , Genotipo , Calor , Trastornos de Estrés por Calor/veterinaria
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