Low Environmental Temperature Exacerbates Severe Acute Respiratory Syndrome Coronavirus 2 Infection in Golden Syrian Hamsters

Background The effect of low environmental temperature on viral shedding and disease severity of COVID-19 is uncertain. Methods We investigated the virological, clinical, pathological, and immunological changes in hamsters housed at room (21 oC), low (12-15 oC), and high (30-33 oC) temperature after challenge by 10 5 plaque-forming units of SARS-CoV-2. Results The nasal turbinate, trachea, and lung viral load and live virus titre were significantly higher (~0.5-log10 gene copies/β-actin, p<0.05) in the low temperature group at 7 days post-infection (dpi). The low temperature group also demonstrated significantly higher level of TNF-α, IFN-γ, IL-1β, and CCL3, and lower level of the antiviral IFN-α in lung tissues at 4dpi than the other two groups. Their lungs were grossly and diffusely haemorrhagic, with more severe and diffuse alveolar and peribronchiolar inflammatory infiltration, bronchial epithelial cell death, and significantly higher mean total lung histology scores. By 7dpi, the low temperature group still showed persistent and severe alveolar inflammation and haemorrhage, and little alveolar cell proliferative changes of recovery. The viral loads in the oral swabs of the low temperature group were significantly higher from 10-17dpi by about 0.5-1.0-log10 gene copies/β-actin. The mean neutralizing antibody titre of the low temperature group was significantly (p<0.05) lower than that of the room temperature group at 7dpi and 30dpi. Conclusions This study provided in-vivo evidence that low environmental temperature exacerbated the degree of virus shedding, disease severity, and tissue proinflammatory cytokines/chemokines expression, and suppressed the neutralizing antibody response of SARS-CoV-2-infected hamsters. Keeping warm in winter may reduce the severity of COVID-19.

Technical and operative factors affecting magnetic resonance imaging–guided focused ultrasound thalamotomy for essential tremor: experience from 250 treatments

OBJECTIVE Magnetic resonance imaging–guided focused ultrasound (MRgFUS) provides real-time monitoring of patients to assess tremor control and document any adverse effects. MRgFUS of the ventral intermediate nucleus (VIM) of the thalamus has become an effective treatment option for medically intractable essential tremor (ET). The aim of this study was to analyze the correlations of clinical and technical parameters with 12-month outcomes after unilateral MRgFUS thalamotomy for ET to help guide future clinical treatments. METHODS From October 2013 to January 2019, data on unilateral MRgFUS thalamotomy from the original pivotal study and continued-access studies from three different geographic regions were collected. Authors of the present study retrospectively reviewed those data and evaluated the efficacy of the procedure on the basis of improvement in the Clinical Rating Scale for Tremor (CRST) subscore at 1 year posttreatment. Safety was based on the rates of moderate and severe thalamotomy-related adverse events. Treatment outcomes in relation to various patient- and sonication-related parameters were analyzed in a large cohort of patients with ET. RESULTS In total, 250 patients were included in the present analysis. Improvement was sustained throughout the 12-month follow-up period, and 184 (73.6%) of 250 patients had minimal or no disability due to tremor (CRST subscore < 10) at the 12-month follow-up. Younger age and higher focal temperature (Tmax) correlated with tremor improvement in the multivariate analysis (OR 0.948, p = 0.013; OR 1.188, p = 0.025; respectively). However, no single statistically significant factor correlated with Tmax in the multivariate analysis. The cutoff value of Tmax in predicting a CRST subscore < 10 was 55.8°C. Skull density ratio (SDR) was positively correlated with heating efficiency (β = 0.005, p < 0.001), but no significant relationship with tremor improvement was observed. In the low-temperature group, 1–3 repetitions to the right target with 52°C ≤ Tmax ≤ 54°C was sufficient to generate sustained tremor suppression within the investigated follow-up period. The high-temperature group had a higher rate of balance disturbances than the low-temperature group (p = 0.04). CONCLUSIONS The authors analyzed the data of 250 patients with the aim of improving practices for patient screening and determining treatment endpoints. These results may improve the safety, efficacy, and efficiency of MRgFUS thalamotomy for ET.

Time to awakening tendency and withdrawal of life supporting treatment (WLST) in patients treated with therapeutic hypothermia after cardiac arrest

Funding Acknowledgements Type of funding sources: None. Introduction and objectives Treatment with therapeutic hypothermia after cardiac arrest remains controversial. It is still unclear how long it takes these patients to recover neurological responsiveness, and the time until awakening varies widely. The aim of our study was to identify the patients who had a later awakening and the factors related to late post-arrest awakening. Methods We performed a retrospective analysis of patients admitted in the Coronary Care Unit between 2006 and 2020 after a cardiac arrest. Patients were eligible if they remained comatose after return of spontaneous circulation (ROSC), with a Glasgow Coma Scale less than 10. We measured the time until awakening, defined as obedience to verbal commands. Results Amongst 271 cardiac arrest survivors, 182 remained comatose. Mean age was 65,8 ± 0,98 and there were 29% of females. 70 patients (38,5%) were treated with therapeutic hypothermia with a target temperature of 33ºC using an endovascular device. 60 patients (33%) awakened and median time of awakening was 4 days. The tendency of the awakening was similar if the patient was or not cooled before (Figure1: median: 4, p25: 3, p75: 6). 18 patients (30%) regained neurological responsiveness 5 days after cardiac arrest without differences between groups (p &gt;0,001) (Figure 2: 28,2% cooling group versus 33,3% no control temperature group). We did not find variables associated with a later awakening in the multiple logistic regression analysis adjusted for age, sex, hospital admission year, initial rhythm and Glasgow Scale, and therapeutic hypothermia use. Conclusions The main cause of mortality after a cardiac arrest is the withdrawal of life support treatment. In our cohort, one third of the patients were late awakaners. Therefore, and in consistency with previous reports, we consider that the observation period to assess the neurological outcome should be extended to more than five days before WLST. Abstract Figure 1 and 2

High Ambient Temperature Aggravates Experimental Autoimmune Uveitis Symptoms

Whether ambient temperature influences immune responses leading to uveitis is unknown. We thus tested whether ambient temperature affects the symptoms of experimental autoimmune uveitis (EAU) in mice and investigated possible mechanisms. C57BL/6 mice were kept at a normal (22°C) or high temperature (30°C) housing conditions for 2 weeks and were then immunized with human interphotoreceptor retinoid-binding protein (IRBP651–670) peptide to induce EAU. Histological changes were monitored to evaluate the severity of uveitis. Frequency of Th1 cells and Th17 cells was measured by flow cytometry (FCM). The expression of IFN-γ and IL-17A mRNA was measured by real-time qPCR. The generation of neutrophil extracellular traps (NETs) was quantified by enzyme-linked immunosorbent assay (ELISA). Differential metabolites in the plasma of the mice kept in the aforementioned two ambient temperatures were measured via ultra-high-performance liquid chromatography triple quadrupole mass spectrometry quadrupole time of flight mass spectrometry (UHPLC-QQQ/MS). The differential metabolites identified were used to evaluate their effects on differentiation of Th1 and Th17 cells and generation of NETs in vitro. The results showed that EAU mice kept at high temperature experienced a more severe histopathological manifestation of uveitis than mice kept at a normal temperature. A significantly increased frequency of Th1 and Th17 cells in association with an upregulated expression of IFN-γ and IL-17A mRNA was observed in the splenic lymphocytes and retinas of EAU mice in high temperature. The expression of NETs as evidenced by myeloperoxidase (MPO) and neutrophil elastase (NE), was significantly elevated in serum and supernatants of neutrophils from EAU mice kept at high temperature compared to the normal temperature group. The metabolites in the plasma from EAU mice, fumaric acid and succinic acid, were markedly increased in the high temperature group and could induce the generation of NETs via the NADPH oxidase-dependent pathway, but did not influence the frequency of Th1 and Th17 cells. Our findings suggest that an increased ambient temperature is a risk factor for the development of uveitis. This is associated with the induction of Th1 and Th17 cells as well as the generation of NETs which could be mediated by the NADPH oxidase-dependent pathway.

Impact of hypothermia on the biomechanical effect of epithelium-off corneal cross-linking

Background The corneal cross-linking (CXL) photochemical reaction is essentially dependent on oxygen and hypothermia, which usually leads to higher dissolved oxygen levels in tissues, with potentially greater oxygen availability for treatment. Here, we evaluate whether a reduction of corneal temperature during CXL may increase oxygen availability and therefore enhance the CXL biomechanical stiffening effect in ex vivo porcine corneas. Methods One hundred and twelve porcine corneas had their epithelium manually debrided before being soaked with 0.1% hypo-osmolaric riboflavin. These corneas were equally assigned to one of four groups. Groups 2 and 4 underwent accelerated epithelium-off CXL using 9 mW/cm2 irradiance for 10 min, performed either in a cold room temperature (group 2, 4 °C) or at standard room temperature (group 4, 24 °C). Groups 1 and 3 served as non-cross-linked, temperature-matched controls. Using a stress-strain extensometer, the elastic moduli of 5-mm wide corneal strips were analyzed as an indicator of corneal stiffness. Results Accelerated epithelium-off CXL led to significant increases in the elastic modulus between 1 and 5% of strain when compared to non-cross-linked controls (P < 0.05), both at 4 °C (1.40 ± 0.22 vs 1.23 ± 0.18 N/mm) and 24 °C (1.42 ± 0.15 vs 1.19 ± 0.11 N/mm). However, no significant difference was found between control groups (P = 0.846) or between groups in which CXL was performed at low or standard room temperature (P = 0.969). Conclusions Although initial oxygen availability should be increased under hypothermic conditions, it does not appear to play a significant role in the biomechanical strengthening effect of epithelium-off CXL accelerated protocols in ex vivo porcine corneas.

Effects of Temperature on Colour of Selected Pig Organs in Silicone (S10) Plastination

Background: Temperature is one of the most important factors that are responsible for plastination procedure.Objective: The present study was designed to determine a suitable method of plastination of skeletal muscle in a low-resource setting in Bangladesh.Methods: This observational study was carried out in the Department of Anatomy, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh, between March 2015 and February 2016. Six whole pig kidneys (as firmer organ) and six whole pig lungs (as softer organs) were collected from a government authorized slaughterhouse in Dhaka city. Same numbers of organs were designated as ‘Cold Temperature Group’ and ‘Room Temperature Group’. We observed the change in colour at cold and room temperatures after different stages of plastination with a colour chart.Results: After fixation, both the brownish kidneys and reddish pink lungs turned brownish and darker. After dehydration, both the kidneys and lungs got paler. After forced impregnation, the colour turned much darker in both groups. The colour change continued towards a darker tone with time. The specific colour changes quantified into frequencies were very variable in both temperature groups.Conclusion: In observed colour changes, the difference was indeterminate.International Journal of Human and Health Sciences Vol. 05 No. 03 July’21 Page: 324-329

Effect of Exercise Training on Body Temperature in the Elderly: A Retrospective Cohort Study

Background: This study evaluated the effect of exercise training on body temperature and clarified the relationship between body temperature and body composition in the elderly. Methods: In this retrospective cohort study, a total of 91 elderly participants performed aerobic and anaerobic exercise training twice a week for 2 years. Non-contact infrared thermometer and bioelectrical impedance analysis were performed at baseline and at 2 years. Results: Mean age of study participants was 81.0 years. The participants were divided into two groups by baseline body temperature of 36.3 °C; lower body temperature group (n = 67) and normal body temperature group (n = 24). Body temperature rose significantly after exercise training in the lower body temperature group (36.04 ± 0.11 °C to 36.30 ± 0.13 °C, p < 0.0001), whereas there was no significant difference in the normal body temperature group (36.35 ± 0.07 °C to 36.36 ± 0.13 °C, p = 0.39). A positive correlation was observed between the amount of change in body temperature and baseline body temperature (r = −0.68, p < 0.0001). Increase in skeletal muscle mass was an independent variable related to the rise in body temperature by the multivariate logistic regression analysis (odds ratio: 4.77, 95% confidence interval: 1.29–17.70, p = 0.02). Conclusions: Exercise training raised body temperature in the elderly, especially those with lower baseline body temperature.

Role of Thermodynamics and Kinetics in the Composition of Ternary III-V Nanowires

We explain the composition of ternary nanowires nucleating from a quaternary liquid melt. The model we derive describes the evolution of the solid composition from the nucleated-limited composition to the kinetic one. The effect of the growth temperature, group V concentration and Au/III concentration ratio on the solid-liquid dependence is studied. It has been shown that the solid composition increases with increasing temperature and Au concentration in the droplet at the fixed In/Ga concentration ratio. The model does not depend on the site of nucleation and the geometry of monolayer growth and is applicable for nucleation and growth on a facet with finite radius. The case of a steady-state (or final) solid composition is considered and discussed separately. While the nucleation-limited liquid-solid composition dependence contains the miscibility gap at relevant temperatures for growth of InxGa1−xAs NWs, the miscibility gap may be suppressed completely in the steady-state growth regime at high supersaturation. The theoretical results are compared with available experimental data via the combination of the here described solid-liquid and a simple kinetic liquid-vapor model.

Effects of ambient temperature on body size and organ development in broilers

The current study investigated the effect of poultry house temperature change on the growth and development of both broiler chickens themselves and the development of their individual organs. Following 42 days of rearing, results showed that the body oblique length, chest width, chest depth, chest angle, keel length, pelvic width, and tibial length of broilers in the low temperature group were significantly lower than those of the control group (P<0.05), while the breast depth of broiler chickens in the high-temperature group was significantly lower than those in the control group (P<0.05). Furthermore, low temperatures significantly increased the function of the heart, liver, spleen and pancreas of broiler chickens (P<0.05). After 7 days of rearing, the bursal index of broilers in the high temperature group was significantly higher than in the control group as well as in the low temperature group (P<0.05). Previous research has established that high and low temperatures significantly affect the growth and development as well as the immunity of broiler chickens, namely that low environmental temperatures have a more adverse effect on broiler chickens than high temperatures. Consequently, using and maintaining high temperatures early in rearing helps to improve the immunity of broilers and improve their performance. The results of our study provides an opportunity to provide both a theoretical and a practical basis for accurate temperature setting in poultry houses for effective breeding of broiler chickens, which will make it possible to increase the productivity of broiler chickens and increase the economic efficiency of the poultry house. Key words: temperature, breeding, body weight, organ development, broilers chickens.

EFFECTS OF LONG-TERM RELATIVELY HIGH AND LOW TEMPERATURE USE ON GROWTH PERFORMANCE AND MEAT QUALITY OF BROILERS

The experiment aims to study the effects of long-term relatively high and low temperatures on growth performance and meat quality of broiler chickens. The experiment was carried out in Yunnan Academy of Animal Science, for determine the quality of meat used the laboratories of Henan Institute of Science and Technology. A total of experiment use 240 healthy 1-day-old Avian broiler chickens were randomly divided into three groups: relatively high temperature group, low temperature group and control group. The results of the experiment confirm that at low temperatures, when the energy consumption of the animal decreases, it leads to weight loss, which we can see in the low-temperature group, the average daily weight gain in this experiment was significantly lower than in the control group (P <0.05). It was found that low-temperature stress significantly increased the mortality of broilers, at the age of 42 days in the low-temperature group, the mortality of chickens was higher than in the control group, by 71.4%. Among all evaluated groups on the content of unsaturated fatty acids SFA, PUFA, MUFA and EFA in the muscles of the breasts of broilers, the lowest content was in the lower temperature group than in the control group, by 48.3%, 46.9%, 51.5% and 43.9%. Studies have shown that influence of high-temperature above 30°C causes disturbances in poultry behavior and physiology, leading to reduced production performance. Broilers aged 35-40 days experienced 31°C high-temperature stress and found that their performance and immunity decreased. Broilers feed intake and growth rate at 35°C high temperature were reduced by 13% and 32% than at 20°C. The results showed that: ① Relatively high temperature and low temperature for a long time reduced the growth performance and mortality of broilers, and long-term relatively low temperature decreased the slaughter performance of broilers.② Relatively high and low temperatures for a long period of time reduced the levels of serine, glycine, SFA, PUFA, USFA, EFA and MUFA in broiler breast muscles negative effect on meat quality. ③ The long-term relatively low temperature has a greater adverse effect on broilers than the long-term relatively high temperature. The results provided some theoretical basis for accurately setting the broiler breeding environment temperature, improving broiler quality, maximizing broiler production performance, and increasing the economic benefits of the farm.