ObjectiveTo quantify the global burden of chronic obstructive pulmonary disease (COPD) attributable to high temperature, low temperature, and non-optimal temperature from 1990 to 2021 using the Global Burden of Disease (GBD) 2021 data. MethodsBased on the GBD 2021 data, we analyzed global, regional, and national COPD mortality and disability-adjusted life years (DALYs) from COPD attributable to high, low, and non-optimal temperatures. Joinpoint regression, age-period-cohort modeling, and Bayesian prediction models were employed. ResultsGlobally, age-standardized mortality rates (ASMR) and age-standardized DALYs rates (ASDR) for COPD attributable to low temperature and non-optimal temperature declined. However, the burden from high temperature increased. Low temperature consistently exerted a greater burden than high temperature across all metrics. Significant geographical disparities emerged: high-temperature mortality was highest in South Asia; low-temperature burden was most severe in East Asia; and high-income North America exhibited accelerated high-temperature mortality growth. The highest low-temperature burden occurred in middle-SDI region, while high-temperature impacts predominated in low-middle-SDI region. Age patterns showed rising high-temperature burden in the 15-39 age group and increasing low-temperature burden among adults ≥80 years old. Bayesian projections revealed divergent gender trajectories: a continuing decline in low-temperature burden for males versus a decelerated decline for females (2020-2030). ConclusionLow temperature exposure remains the primary risk factor for COPD within non-optimal temperatures globally, although high-temperature impacts are increasing. Significant regional variations necessitate targeted interventions for three key populations: older adults vulnerable to cold, working-age adults with occupational heat exposure, and older women requiring rehabilitative support.
Objective To explore impact of climate change on aortic dissection and to put forward a new way about prediction and prevention of aortic dissection. Methods We retrospectively analyzed the characteristics of acute aortic dissection patients came from Hebei province in Fuwai Hospital between 2010 and 2016 year. Meanwhile, we collected monthly maximum temperature, minimum temperature, average temperature, average pressure, amount of rainfall, sunshine, humidity and other meteorological data. Generalized model was implied to explore climate change and the incidence of aortic dissection. Results A total of 1 121 acute aortic dissection patients from Hebei province were admitted in Fuwai Hospital during the period of 6 years. There were 774 patients were type A aortic dissection, and 347 patients were type B aortic dissection. The average age was 51.4±12.0 years. There were 873 males and 248 females. There were 889 (79.3%) patients with hypertension, 99 (8.83%) with Marfan syndrome. It was found that temperature, humidity and air pressure were all statistically significant for indication aortic dissection through single variable analysis (P<0.01). The temperature was only variable by one-way analysis of variance (P<0.01). The lowest temperature has the best predictive effect on the occurrence of aortic dissection. The relative risk was 1.02 with 95% confidence interval 1.02 to 1.03. Conclusion The change of climatic conditions can affect the occurrence of aortic dissection, and the lowest temperature is an important trigger factor for aortic dissection onset.
In recent years, target temperature management (TTM) has been increasingly applied to cardiac arrest patients, and programs and strategies for TTM are in a constant state of update and refinement. This paper analyzes and proposes relevant strategies from the concept of TTM, its clinical application status for cardiac arrest patients in domestic and international medical institutions, its deficiencies in the clinical practice, and factors affecting the development of TTM, with a view to providing a realistic basis for the development of high-quality TTM in medical institutions.
By studying the relationship between fingertip temperature changes and arterial function during vascular reactivity test, we established a new non-invasive method for detecting vascular function, in order to provide an assistance for early diagnosis and prevention of cardiovascular diseases. We customized three modules respectively for blood occlusion, measurement of finger temperature and blood oxygen acquisition, and then we established the hardware of data acquisition system. And the software was programmed with Labview. Healthy subjects [group A, n=24, (44.6±9.0) years] and subjects with cardiovascular diseases [group B, n=33, (57.2±9.9) years)] were chosen for the study. Subject's finger temperature, blood oxygen and occlusion pressure of block side during and after unilateral arm brachial artery occlusion were recorded, as well as some other regular physiological indexes. By time-domain analysis, we extracted 12 parameters from fingertip temperature signal, including the initial temperature (Ti), temperature rebound (TR), the time of the temperature recovering to initial status (RIt) and other parameters from the finger temperature signal. We in the experiment also measured other regular physiological body mass index (BMI), systolic blood pressure (SBP), diastiolic blood pressure (DBP) and so on. Results showed that 8 parameters difference between the two group of data were significant. based on the statistical results. A discriminant function of vascular function status was established afterwards. We found in the study that the changes of finger temperature during unilateral arms brachial artery occlusion and open were closely related to vascular function. We hope that the method presented in this article could lay a foundation of early detection of vascular function.
Patch clamp is a technique that can measure weak current in the level of picoampere (pA). It has been widely used for cellular electrophysiological recording in fundamental medical researches, such as membrane potential and ion channel currents recording, etc. In order to obtain accurate measurement results, both the resistance and capacitance of the pipette are required to be compensated. Capacitance compensations are composed of slow and fast capacitance compensation. The slow compensation is determined by the lipid bilayer of cell membrane, and its magnitude usually ranges from a few picofarads (pF) to a few microfarads (μF), depending on the cell size. The fast capacitance is formed by the distributed capacitance of the glass pipette, wires and solution, mostly ranging in a few picofarads. After the pipette sucks the cells in the solution, the positions of the glass pipette and wire have been determined, and only taking once compensation for slow and fast capacitance will meet the recording requirements. However, when the study needs to deal with the temperature characteristics, it is still necessary to make a recognition on the temperature characteristic of the capacitance. We found that the time constant of fast capacitance discharge changed with increasing temperature of bath solution when we studied the photothermal effect on cell membrane by patch clamp. Based on this phenomenon, we proposed an equivalent circuit to calculate the temperature-dependent parameters. Experimental results showed that the fast capacitance increased in a positive rate of 0.04 pF/℃, while the pipette resistance decreased. The fine data analysis demonstrated that the temperature rises of bath solution determined the kinetics of the fast capacitance mainly by changing the inner solution resistance of the glass pipette. This result will provide a good reference for the fine temperature characteristic study related to cellular electrophysiology based on patch clamp technique.
ObjectiveTo systematically review the efficacy and safety of intravascular cooling versus surface cooling for induced mild hypothermia on the prognosis of patients with cardiac arrest (CA) after resuscitation.MethodsPubMed, EMbase, The Cochrane Library, CNKI and WanFang Data databases were electronically searched to collect cohort studies and randomized controlled trials (RCTs) about the efficacy and safety of intravascular cooling versus surface cooling for CA patients after resuscitation from inception to July 2019. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies, then, meta-analysis was performed by using Stata 13.0 software.ResultsA total of 9 cohort studies and 3 RCTs involving 2 104 patients were included. The results of meta-analysis showed that: the rate of good neurological function was significantly higher (OR=1.45, 95%CI 1.18 to 1.78, P<0.001) and the induction time was significantly shorter (SMD=?1.35, 95%CI ?2.34 to ?0.36, P=0.008) in the intravascular cooling group, but there was no statistical difference in mortality between two groups (OR=0.84, 95%CI 0.70 to 1.00, P=0.053). In terms of complications related to mild hypothermia, the rate of excessive hypothermia (OR=0.27, 95%CI 0.18 to 0.41, P<0.001) and arrhythmia (OR=0.60, 95%CI 0.40 to 0.89, P=0.012) was significantly lower in the patients treated with intravascular cooling, but the incidence of coagulopathy was higher (OR=1.61, 95%CI 1.05 to 2.49, P=0.03). There was no statistical difference in the incidence of pneumonia between two groups (OR=1.20, 95%CI 0.94 to 1.53, P=0.147).ConclusionCurrent evidence shows that intravascular cooling has significant neurological protection for patients with CA compared with surface cooling since it can decrease the induction time and the rate of excessive hypothermia and arrhythmia, but it may have a negative effect on the coagulation function. Due to the limited quality and quantity of the included studies, more high-quality studies are needed to verify the above conclusion.
Objective To evaluate which is better method zymogen or low temperature frozen in removing vascular endothelial cell so as to lay a foundation for creating a kind of brace which is not to be rejected and the same as own blood vessel. Methods Fresh and not damaged umbilical blood vessel was collected from natural labour women, human umbilical blood vessel was remove carefully from normal foetus, then was put into disinfectant at 37℃ for 24 hours. They were divided into 3 groups:normal group(NG),zymogen group(ZG) and low temperature frozen group(LG). ZG: 0.1% collagenⅡ enzyme was addedin umbilical blood vessel and closed the both sides and the vascular endothelialcell was removed in 37℃ water. LG:Umbilical blood vessel was put into liquidnitrogen for 24 hours after frozened step by step, and then it was put into 37℃ water for 30-60 s and the vascular endothelial cells were washed away by normal saline. NG:Umbilical blood vessel was kept into 4℃ Kerb’s liquid. The bacteria were culturedin each group. The samples were stained by HE,elastic fiber and collagen fiberwere observed by light and scanning electron microscope. The difference of compliance was compared. Human leukocyte antigen ABC(HLA-ABC) and HLA-DR were observed by immunohistochemical method and the expression of antigen of umbilical blood vessel was analysed. Results In LG, umbilical vascular endothelial cells were removed completely; artery showed vertical smooth muscle and vein showed elastic membrane. InZG, umbilical vascular endothelial cells were removed completely after 20 minutes;artery showed vertical smooth muscle cells and vein showed lower endothelial layer. The vascular compliance in LG was higher than that in NG, and the latter was also higher than that in ZG,but showing no significant differences (Pgt;0.05). The compliance of umbilical vein was 2-3 times as much asthat of umbilical artery.The expression of HLA-ABC and HLA-DR in LG andZG were lower than that in NG, showing significant differences (Plt;0.01). Conclusion Low temperature frozen methodand zymogen method(0.1% collagen Ⅱ enzyme for 20 min) can remove vascular endothelial cells of human umbilical blood vessel completely.Low temperature frozenmethod was better than zymogen method.
Numerical simulation is one of the most significant methods to predict the temperature distribution in high-intensity focused ultrasound (HIFU) therapy. In this study, the adopted numerical simulation was used based on a transcranial ultrasound therapy model taking a human skull as a reference. The approximation of the Westervelt formula and the Pennes bio-heat conduction equation were applied to the simulation of the transcranial temperature distribution. According to the temperature distribution and the Time Reversal theory, the position of the treatable focal region was corrected and the hot spot existing in the skull was eliminated. Furthermore, the influence of the exposure time, input power and the distance between transducer and skull on the temperature distribution was analyzed. The results showed that the position of the focal region could be corrected and the hot spot was eliminated using the Time Reversal theory without affecting the focus. The focal region above 60℃ could be formed at the superficial tissue located from the skull of 20 mm using the hot spot elimination method and the volume of the focal region increases with the exposure time and the input power in a nonlinear form. When the same volume of the focal region was obtained, the more power was inputted, the less the exposure time was needed. Moreover, the volume of the focal region was influenced by the distance between the transducer and the skull.
ObjectiveTo study the method of rapid and accurate measurement of body temperature in dense population during the coronavirus disease 2019 pandemic.MethodsFrom January 27th to February 8th, 2020, subjects were respectively measured with two kinds of non-contact infrared thermometers (blue thermometer and red one) to measure the temperature of forehead, neck, and inner side of forearm under the conditions of 4–6℃ (n=152), 7–10℃ (n=103), and 11–25℃ (n=209), while the temperature of axillary was measured with mercury thermometer under the same conditions. Taking the mercury thermometer temperature as the gold standard, the measurement results with non-contact infrared thermometers were compared.ResultsAt 7–10℃, there was no statistical difference among the forehead temperatures measured by the two non-contact infrared thermometers and the axillary temperature (P>0.05); there was no difference among the temperature measured by blue thermometer on forehead, neck, and inner side of forearm (P>0.05); no difference was found between the temperature measured by the red thermometer on forehead and inner side of forearm (P>0.05), while there was statistical difference between the temperatures measured by the red thermometer on forehead and neck (P<0.05). Under the environment of 11?25℃, there was no statistical difference among the forehead temperatures measured by the two infrared thermometers and the axillary temperature (P>0.05); the difference between the temperatures of forehead and inner side of forearm measured by the blue thermometer was statistically significant (P<0.05), while no difference appeared between the forehead and neck temperatures measured by the blue thermometer (P>0.05); there was no statistical difference among the temperatures of three body regions mentioned above measured by the red thermometer (P>0.05). According to the manual, the allowable fluctuation range of the blue thermometer was 0.3℃, and that of the red one was 0.2℃. The mean differences in measured values between different measured sites of the two products were within the allowable fluctuation range. Therefore, the differences had no clinical significance in the environment of 7–25℃. Under the environment of 4–6℃, the detection rate of blue thermometer was 2.2% and that of the red one was 19.1%.ConclusionsThere is no clinical difference between the temperature measured by mercury thermometer and the temperature measured by temperature guns at 7–10 or 11–25℃, so temperature guns can be widely used. In order to maintain the maximum distance between the measuring and the measured persons and reduce the infection risk, it is recommended to choose the inner forearm for temperature measurement. Under the environment of ambient temperature 4–6℃, the detection rate of non-contact electronic temperature gun is low, requiring taking thermal measures for the instrument.
【Abstract】Objective To investigate the effects of preservative temperature on pancreatic function and determine the optimal preservative temperature for pancreatic transplantation. MethodsCold pancreatic preservation was performed and a homologous male Wistar rat model of heterotopic total pancreaticoduodenal transplantation was established. The pancreas was preserved for 6 h in UW solution at specific temperatures(0 ℃, 4 ℃, 8 ℃ and 12 ℃). After preservation, pancreatic tissue was taken for histologic examination in every group. ATP and total adenine nucleotides (TAN) were determined by using high performance liquid chromatography (HPLC). Blood glucose(BG), serum amylase and lipase were measured 24 h after transplantation. And the activity of myeloperoxidase (MPO) in the pancreatic grafts was also measured at the same time. Besides, histological observation was performed. Results Microscopic studies showed that the histomorphological changes of pancreas in 4 ℃ group were less obvious than those in other groups. Tissual concentrations of ATP and TAN decreased gradually in 4 ℃ group, 0 ℃ group, 8 ℃ group, and 12 ℃ group after 6 h of preservation(PH＜0.05). The levels of BG, serum lipase and MPO increased gradually in 4 ℃ group, 0 ℃ group, 8 ℃ group, and 12 ℃ group(PH＜0.05). The activity of MPO in 4 ℃ group （1.19±0.16 U/g ）was significantly lower than that of the control group（0.26±0.09 U/g，PH＜0.05). Conclusion The temperature of 4 ℃ is most appropriate for hypothermic pancreatic preservation and can considerably alleviate cold ischemic injury of rat pancreas.