An analysis of results of 392 times of CT quality control and room radiological protection testing in Guangdong Province, China / 中国辐射卫生

Objective To provide a theoretical basis for radiation health supervision through an analysis of the situation of computed tomography (CT) equipment quality control and CT room radiological protection in Guangdong Province, China in recent years. Methods We collected the data of 392 times of CT quality control and radiological protection testing by a third-party radiological health technical service institution in Guangdong Province from 2019 to 2021. We analyzed the levels of CT-owning hospitals, CT manufacturers, CT quality control test results, and the pass rate of radiation protection tests. Results The examined CT scanners were from different levels of hospitals in Guangdong Province, and were manufactured by nine major CT equipment manufacturers at home and abroad. The pass rate of CT room radiological protection was 99.88%, and the ambient dose equivalent rates of five monitoring points exceeded the limit, with four at the control room door and one at the shield wall of the room. The overall pass rate of CT equipment quality control was 99.49%, and the non-conforming parameters were the accuracy of positioning light and the deviation of reconstructed slice thickness. Conclusion In recent years, CT equipment quality control and room radiation protection in Guangdong Province have been at a high level.

Association between temperature and mortality: a multi-city time series study in Sichuan Basin, southwest China

BACKGROUND@#There are few multi-city studies on the association between temperature and mortality in basin climates. This study was based on the Sichuan Basin in southwest China to assess the association of basin temperature with non-accidental mortality in the population and with the temperature-related mortality burden.@*METHODS@#Daily mortality data, meteorological and air pollution data were collected for four cities in the Sichuan Basin of southwest China. We used a two-stage time-series analysis to quantify the association between temperature and non-accidental mortality in each city, and a multivariate meta-analysis was performed to obtain the overall cumulative risk. The attributable fractions (AFs) were calculated to access the mortality burden attributable to non-optimal temperature. Additionally, we performed a stratified analyses by gender, age group, education level, and marital status.@*RESULTS@#A total of 751,930 non-accidental deaths were collected in our study. Overall, 10.16% of non-accidental deaths could be attributed to non-optimal temperatures. A majority of temperature-related non-accidental deaths were caused by low temperature, accounting for 9.10% (95% eCI: 5.50%, 12.19%), and heat effects accounted for only 1.06% (95% eCI: 0.76%, 1.33%). The mortality burden attributable to non-optimal temperatures was higher among those under 65 years old, females, those with a low education level, and those with an alternative marriage status.@*CONCLUSIONS@#Our study suggested that a significant association between non-optimal temperature and non-accidental mortality. Those under 65 years old, females, and those with a low educational level or alternative marriage status had the highest attributable burden.

Spatiotemporally resolved metabolomics and isotope tracing reveal CNS drug targets

Deconvolution of potential drug targets of the central nervous system (CNS) is particularly challenging because of the complicated structure and function of the brain. Here, a spatiotemporally resolved metabolomics and isotope tracing strategy was proposed and demonstrated to be powerful for deconvoluting and localizing potential targets of CNS drugs by using ambient mass spectrometry imaging. This strategy can map various substances including exogenous drugs, isotopically labeled metabolites, and various types of endogenous metabolites in the brain tissue sections to illustrate their microregional distribution pattern in the brain and locate drug action-related metabolic nodes and pathways. The strategy revealed that the sedative-hypnotic drug candidate YZG-331 was prominently distributed in the pineal gland and entered the thalamus and hypothalamus in relatively small amounts, and can increase glutamate decarboxylase activity to elevate γ-aminobutyric acid (GABA) levels in the hypothalamus, agonize organic cation transporter 3 to release extracellular histamine into peripheral circulation. These findings emphasize the promising capability of spatiotemporally resolved metabolomics and isotope tracing to help elucidate the multiple targets and the mechanisms of action of CNS drugs.

Effects of long-term exposure to ambient PM2.5 on hypertension and role of dietary regulation / 环境与职业医学

Background The contribution of long-term ambient PM2.5 exposure to hypertension should not be ignored. However, the conclusions of whether dietary factors play a role in regulating PM2.5-related hypertension are still inconsistent. Objective To explore the correlation between long-term exposure to ambient PM2.5 and blood pressure indicators (systolic blood pressure, diastolic blood pressure, mean arterial pressure, and pulse pressure) in adults in Ningxia and a potential moderating effect of dietary factors. Methods A set of cross-sectional survey data from March, 2013 to May, 2018 was retrieved from the China Northwest Cohort-Ningxia, and the average ambient PM2.5 concentration in the previous three years was also collected to estimate the long-term exposure of the participants. Binary logistic regression model was used to validate the correlation between long-term exposure to ambient PM2.5 and hypertension in Ningxia, and linear model was used to study the correlation between long-term exposure to ambient PM2.5 and blood pressure indicators (systolic blood pressure, diastolic blood pressure, mean arterial pressure and pulse pressure), and to explore the influence of dietary factors on ambient PM2.5-related hypertension. Results A total of 11470 participants were included in the study, 42.2% male and 57.8% female. The three-year average ambient PM2.5 concentration before the baseline survey was 37.0 μg·m−3. Each 1 μg·m−3 increase in ambient PM2.5 was associated with an increased risk of hypertension (OR=1.111, 95%CI: 1.097, 1.125), and increased systolic blood pressure, diastolic blood pressure, mean arterial pressure, and pulse pressure by 0.886 (95%CI: 0.783, 0.990), 0.570 (95%CI: 0.500, 0.641), 0.676 (95%CI: 0.600, 0.751), and 0.316 (95%CI: 0.243, 0.389) mmHg, respectively. The stratified analysis showed that the OR and 95%CI of hypertension were 1.171 (1.097, 1.254), 1.117 (1.064, 1.174), and 1.160 (1.116, 1.207) respectively for each 1 μg·m−3 increased in PM2.5 with low frequency of vegetable and fruit consumption and salty taste respectively. The OR and 95%CI of hypertension were decreased when the moderate and high frequency of vegetable and fruit intake and moderate and light taste applied, the values were 1.091 (1.062, 1.121) and 1.114 (1.097, 1.131), 1.105 (1.082, 1.129) and 1.111 (1.092, 1.13), 1.115 (1.090, 1.140) and 1.102 (1.083, 1.121) respectively. Compared with low frequency of vegetable and fruit intake and salty taste, the increase degree of ambient PM2.5 related systolic blood pressure, diastolic blood pressure, mean arterial pressure and pulse pressure also decreased in middle and high frequency of vegetable and fruit intake and moderate and light taste. Conclusion Long-term exposure to ambient PM2.5 is significantly associated with increased risks of hypertension and blood pressure in Ningxia area. Increasing the frequency of vegetable and fruit intake and decreasing salty taste may reduce the effect of ambient PM2.5 on hypertension and blood pressure.

Development of a portable radiation detector for nuclide identification based on CdZnTe / 中国辐射卫生

Objective To develop a portable nuclear radiation detector with low-energy γ-nuclide recognition capability for rapid measurement of the dose levels in low-energy radiation fields and identification of nuclides. Methods A digital multi-channel circuit was developed for a detector based on the room temperature semiconductor cadmium zinc telluride, nuclide recognition was achieved using an intelligent nuclide recognition algorithm, and the energy response function G(E) was used to calculate the real-time ambient dose equivalent rate H*(10). Results The portable spectrometer had a minimum detectable energy of 20 keV, and the typical energy resolution for low-energy X-rays was > 4.10% at 59.5 keV and 20℃, enabling accurate identification of 241Am nuclide. Conclusion The device has a good measurement performance for low-energy γ/X rays, effectively addressing the limitations of existing devices for monitoring low-energy radiation fields, and provide reliable technical methods for monitoring and emergency response in spent fuel reprocessing plants or nuclear material production plants.

Study on the effect of temperature on the risk of hand, foot and mouth disease in Chengdu / 公共卫生与预防医学

Objective To explore the effect of temperature on the risk of hand-foot-and-mouth disease (HFMD) and population susceptibility. Methods The data of HFMD cases in Chengdu from January 1, 2016 to October 31, 2022 were collected, and local meteorological data during the same period were also collected. Distributional lag nonlinear models were developed. The relative risk (RR) of morbidity at different temperatures and different lags was calculated. Differences in the relative risk levels of different populations were analyzed and compared. Results A total of 263 776 cases of HFDM were reported in Chengdu during the study period. The distribution of HFMD was periodic. For the overall population, the short-term average temperature and RR showed a “U”-shaped relationship. When the lag time was 0-7 days, the cumulative RR was 1.59 (95%CI: 1.18-2.14) at the average temperature of -0.5℃ and 2.16 (95%CI: 1.60-2.91) at the average temperature of 34.5℃. The RR values under high and low temperatures decreased with increasing lag period. When the lag time was extended, the average temperature and RR showed an inverted “U”-shaped relationship, with higher RR at moderate temperatures and increasing as the lag period increased. The results of the subgroups showed that the RR of onset among scattered children was higher at high and low temperatures. Conclusion The risk effect of temperature on the onset of HFMD in different populations is variable and changes with the lag period, and the prevention and control measures should be adjusted in a timely and targeted manner.

Study on the effect of personal radiological protective equipment used in diagnostic radiology / 中华放射医学与防护杂志

Objective:To study the actual effect of the use of personal protective equipment of the examined individuals, and provide reference and basis for the correct use of personal protective equipment and the radiological health administrative law enforcement.Methods:From February to June 2022, the imaging department of Qingdao Municipal Hospital selected 170 patients who underwent X-ray imaging examination (oral panoramic, dental radiography, DR photography, CT scanning), including 25 with oral panoramic and dental radiography, 60 with CT scanning and 60 with DR imaging. The thermoluminescent dosimeter was used to detect the ambient dose equivalent at the point of concern for 170 examined individuals who have used personal protective equipment to cover their sensitive parts, and to analyze the data detected at the same point as above when routinely using the same equipment.Results:There was a statistically significant difference in the dose equivalent at the same points inside and outside the lead neckband ( t=-2.23, P<0.05). There was no statistically significant difference in the dose equivalent at the same point inside and outside the lead collar during dental radiography ( P>0.05). During DR photography (chest PA, lateral and lumbar AP), the examined individuals were wearing lead aprons. Among them, there was a statistically significant difference in the dose equivalent at the same points inside and outside the lead aprons of children′s chest PA and adults′ chest PA ( U=10.00, 19.00, P<0.05). There was no statistically significant difference in the dose equivalent at the same points inside and outside the lead aprons of adult′s chest PA and lumbar AP ( P>0.05). When performing CT scan (chest or upper abdomen), there was a statistically significant difference in the dose equivalent at the same points of wrapped lead aprons( U=878.50, 11.00, P<0.05). Conclusions:The correct use of personal protective equipment is a complex technical problem. It is very important to fully and accurately understand the optimization principle of radiation protection and correctly use personal protective equipment for the examined individuals. The administrative punishment of radiation health on the use of personal protective equipment of the examined individuals should be cautious.

Association between time-weighted individual exposure to ambient pollutants and carotid intima-media thickness / 环境与职业医学

Background Evidence about the association between air pollution and carotid intima-media thickness (CIMT) is inconsistent, and limited studies have explored the relationship between gaseous pollutants and CIMT. Additionally, personal activity patterns and infiltrated ambient pollution are not comprehensively considered to estimate individual exposure to air pollutants. Objective To investigate the relationship between long-term time-weighted individual exposure to ambient pollutants [fine particulate matter (PM2.5), inhalable particulate matter (PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), and carbon monoxide (CO)] and the progression of CIMT. Methods This study was performed among 554 participants in the Beijing Health Management Cohort who were free of atherosclerotic lesions on carotid artery at baseline. Daily concentrations of pollutants were predicted at both residential and work addresses based on land-use regression model. With additional consideration of personal indoor and outdoor activity patterns at both addresses and exposure to ambient pollutants from traffic transportation, individual time-weighted concentration was calculated. Indoor exposure was estimated by infiltrated ambient pollutants (based on infiltration factors and land-use regression model). Personal activity patterns included type, time, location, and frequency. Exposure to ambient pollutants from different traffic transportations was estimated by the average outdoor pollutant concentrations at both residential and work addresses combined within filtration factors and time spent on commuting. Multiple linear regression was conducted to assess the association of time-weighted individual pollutant exposure and the central position of CIMT progression. Quantile regression was applied to explore the relationship between time-weighted individual pollutant exposure and the progression of CIMT on different percentiles. Results The median value of CIMT progression was 369.49 μm·year−1. PM2.5, PM10, SO2, and O3 were associated with CIMT progression in the multiple linear regression model. The largest effect sizes of PM2.5, PM10, and SO2 were obtained for one-year exposure (regression coefficient: 66.910, 64.077, and 191.070, respectively), and two-year exposure for O3 (regression coefficient: 62.197). The results of quantile regression demonstrated different effect sizes for pollutants among different percentiles on CIMT progression. Significant associations between CIMT progression and PM2.5 from P30 to P50, CO from P10 to P40, and PM10 from P30 to P60 were observed. Two-year and three-year exposures to NO2 (P10, P20 and P40) were also associated with CIMT progression. The association between SO2 and the progression of CIMT was proved on all percentiles, and larger effect sizes of one-year and two-year exposures to SO2 (except P90) were demonstrated with increasing percentiles. The upward trend for the coefficients was clearly presented from P50 to P80. Specifically, the coefficient of two-year exposure to SO2 ranged from 136.583 (P50) to 277.330 (P80). No statistically significant association was observed between O3 and CIMT progression on any percentile (P>0.05), and the results were inconsistent with those of the multiple linear regression. Conclusion Individual time-weighted exposures to PM2.5, PM10, SO2, NO2, and CO have the potential to promote the progression of CIMT, and the adverse effect of ambient pollution on atherosclerotic lesion is identified.

Tonstruction of AHI based on the integrating health risks of exposure to air pollution and ambient temperature in Tianjin / 公共卫生与预防医学

Objective To construct an air health index (AHI) based on the exposure-response relationships of air pollution and ambient temperature with the years of life lost (YLL) in Tianjin. Methods The time series database of air pollution, meteorological factors, and non-accidental YLL from 2014-2019 in six urban areas of Tianjin were established. The data from 2014 to 2017 were used as the construction set to establish the exposure-response relationships of air pollution and ambient temperature with non-accidental YLL and establish the AHI model. The data from 2018 to 2019 were used as the validation set for verifying AHI. The generalized additive model (GAM) and weighted quantile sum (WQS) model were used to establish the exposure-response relationship between air pollution mixtures and non-accidental YLL. The distributed lag nonlinear model (DLNM) was fitted to assess the exposure-response relationship between ambient temperature and non-accidental YLL. Based on these obtained coefficients, the AHI and air quality health index (AQHI) were built. By comparing the associations between AHI, air quality health index (AQHI), and air quality index (AQI) with daily mortality and YLL and model goodness of fit to evaluate the validity of AHI. Results The formula for AHIt=EYLLt,air pollution+ambient temperature/475.11*10. The validation results showed that each IQR increase in AHI was associated with a higher increase in non-accidental mortality and YLL (10.61% and 353.37 person-year) compared with the corresponding values of AQHI and AQI. In addition, the model goodness of AHI was better than AQHI and AQI model. Conclusion Compared with AQHI and AQI, the AHI based on the integrating health effects of air pollution and ambient temperature has a better health risk prediction ability.

Geographic information system-based mapping of air pollution & emergency room visits of patients for acute respiratory symptoms in Delhi, India (March 2018-February 2019)

Background & objectives: Studies assessing the spatial and temporal association of ambient air pollution with emergency room visits of patients having acute respiratory symptoms in Delhi are lacking. Therefore, the present study explored the relationship between spatio-temporal variation of particulate matter (PM)2.5 concentrations and air quality index (AQI) with emergency room (ER) visits of patients having acute respiratory symptoms in Delhi using the geographic information system (GIS) approach. Methods: The daily number of ER visits of patients having acute respiratory symptoms (less than or equal to two weeks) was recorded from the ER of four hospitals of Delhi from March 2018 to February 2019. Daily outdoor PM2.5 concentrations and air quality index (AQI) were obtained from the Delhi Pollution Control Committee. Spatial distribution of patients with acute respiratory symptoms visiting ER, PM2.5 concentrations and AQI were mapped for three seasons of Delhi using ArcGIS software. Results: Of the 70,594 patients screened from ER, 18,063 eligible patients were enrolled in the study. Winter days had poor AQI compared to moderate and satisfactory AQI during summer and monsoon days, respectively. None of the days reported good AQI (<50). During winters, an increase in acute respiratory ER visits of patients was associated with higher PM2.5 concentrations in the highly polluted northwest region of Delhi. In contrast, a lower number of acute respiratory ER visits of patients were seen from the ‘moderately polluted’ south-west region of Delhi with relatively lower PM2.5 concentrations. Interpretation & conclusions: Acute respiratory ER visits of patients were related to regional PM2.5 concentrations and AQI that differed during the three seasons of Delhi. The present study providessupport for identifying the hotspots and implementation of focused, intensive decentralized strategies to control ambient air pollution in worst-affected areas, in addition to the general city-wise strategies.

Effect of Packaging Materials and Storage Temperatures on the Microbiological Quality of Hibiscus sabdarifa Drinks during Ambient and Refrigeration Storage

Aims: To evaluate the effect of packaging materials and storage temperatures on the microbiological quality of Hibiscus sabdarifa drinks produced with: 1) commercial pineapple flavour (HCPF) and; 2) Phoenix dactylifera (38%) and pineapple extract (2%) (HPPE). Methodology: Pasteurized drinks packaged in polyethylene sachets, plastic and glass bottles were stored at refrigeration (4.4±2oC) and ambient (25±2oC) temperatures for 27 and 9 days respectively. Results: There was significant (P≤0.05) decrease in total bacterial count in HCPF (≤4.51-≥2.14 Log10CFU/ml) with higher death rate (0.06) in plastic bottles at 4.4±2oC while at 25±2oC it increased significantly (P≤0.05) in HPPE samples (4.00-≤4.95 Log10CFU/ml) with least growth rate in plastic bottles (0.02). Yeast count at 25±2oC (1.28 – 2.15 Log10CFU/ml) was significantly (P≤0.05) higher than at 4.4±2oC (1.00 – 1.60 Log10CFU/ml) and drinks in plastic bottles had the least growth rates (≤0.03). Coliform (2.04 – 2.59 Log10CFU/ml), Escherichia coli (2.00 – 2.93 Log10CFU/ml) and Staphylococcus (2.00 – 2.50 Log10CFU/ml) sparingly detected, were unable to grow in the drinks with greater inhibition at 25±2oC in all packaging materials. No growth of Salmonella was observed in the drinks. Glass bottles favoured more microbial growth but the levels were satisfactory for all packaging which is indicative of microbiological safety. Conclusion: Any of the packaging material can be used for packaging of Hibiscus sabdarifa drinks with storage at refrigeration temperature for ≤ 21 days. It is informative to both consumers and producers that the then wasted pineapple peels can serve as an ingredient in Hibiscus sabdarifa drink production.

Environment type and storage period on eggshell quality of laying hens at different ages / Tipos de ambiente e período de armazenamento sobre a qualidade de casca de ovos de poedeiras comerciais em diferentes idades

ABSTRACT: Eggshell quality is directly linked to the good acceptability of the product by consumers, whereas the industry is concerned with economic losses. Prolonged periods of laying, diseases, nutrition, bird age and genetics can influence egg quality. This study aimed to examine the influence of the environment, bird age and storage period on the physical characteristics of the shell of eggs from commercial laying hens. The experiment involved 288 eggs from Hy-line hens, which were distributed in a completely randomized design with a triple 3×2×4 factorial arrangement represented by three ages (31, 62 or 88 weeks), two storage temperatures (ambient or refrigerated), and four storage periods (one, 10, 20 or 30 days), totaling 24 treatments. Four replications were used with three eggs each. Eggshell strength, percentage and thickness were measured. Differences were observed, with the eggs stored at room temperature exhibiting lower shell strength. Laying eggs at an advanced age (88 weeks) resulted in decreased eggshell strength as compared with the other ages, whereas the eggs from young layers (31 weeks) had a thicker shell. The advancing age of the laying hens reduced eggshell quality, regardless of the storage environment. Nonetheless, the eggs stored in the refrigerator showed better eggshell quality and integrity than those stored at ambient temperature.

RESUMO: A qualidade da casca está diretamente ligada à boa aceitabilidade do produto pelos consumidores, enquanto a indústria se preocupa com as perdas econômicas. Períodos prolongados de postura, doenças, nutrição, idade da ave e genética podem influenciar a qualidade dos ovos. Objetivou-se avaliar a influência do ambiente, idade da ave e período de armazenamento nas características físicas da casca de ovos de poedeiras comerciais. Foram utilizados 288 ovos de poedeiras Hy-line, distribuídos em um delineamento inteiramente casualizado em fatorial triplo 3x2x4, sendo os fatores: três idades (31, 62 e 88 semanas), temperatura de armazenamento (ambiente e refrigerado), e quatro períodos de armazenamento (um, 10, 20 e 30 dias), totalizando 24 tratamentos, com quatro repetições de três ovos. Avaliou-se a resistência, percentual e espessura da casca. Foram observadas diferenças, uma vez que os ovos armazenados em temperatura ambiente apresentaram diminuição na resistência de casca. Ovos de poedeiras em idade avançada (88 semanas) apresentaram pior resistência de casca em relação às demais idades, enquanto ovos provenientes de poedeiras jovens (31 semanas) apresentaram maior espessura de casca. A idade avançada da poedeira reduziu a qualidade de casca dos ovos, independentemente do ambiente de armazenamento. Ainda, os ovos armazenados em geladeira apresentaram melhor qualidade e integridade da casca em comparação com os armazenados ao ambiente.

Construction of quality evaluation strategy for Chinese medicine based on ambient mass spectrometry / 中国中药杂志

Quality is the guarantee for the clinical safety and effectiveness of Chinese medicine. Accurate quality evaluation is the key to the standardization and modernization of Chinese medicine. Efforts have been made in improving Chinese medicine quality and strengthening the quality and safety supervision in China, but rapid and accurate quality evaluation of complex Chinese medicine samples is still a challenge. On the basis of the development of ambient mass spectrometry and the application in quality evaluation of complex Chinese medicine systems in recent years, the authors developed the multi-scenario Chinese medicine quality evaluation strategies. A systematic methodology was proposed in specific areas such as real-time monitoring of the quality of complex Chinese medicine decoction system, rapid toxicity grading of compound Chinese patent medicine, and evaluation of bulk medicinals of Chinese patent medicine. Allowing multi-scenario analysis of Chinese medicine, it is expected to provide universal research ideas and technical methods for rapid and accurate quality evaluation of Chinese medicine and boost the high-quality development of Chinese medicine industry.

A review of progress in research of relationship between air pollution and perinatal depression / 环境与职业医学

In recent years, the increasing incidence of perinatal depression has become an important public health problem. In addition to the traditional social demographic factors, biological factors, obstetric factors, etc., the association between air pollution and perinatal depression (PND) has also attracted more and more attention. In this paper, studies on the association between air pollution and PND were reviewed, especially the associations of PND with ambient air pollutants such as PM2.5, PM10, NO2, and O3 as well as indoor air pollutants such as tobacco smoke, and the characteristics and possible biological mechanisms of the influence of different pollutants on PND were summarized. Based on the available studies, various outdoor air pollutants are associated with PND, and some pollutants may exhibit a dose-response relationship with it. As for indoor air pollution, studies only have focused on the impact of tobacco exposure on PND, and as yet, no study has explored the association between other indoor pollutants (e.g. cooking oil smoke and solid fuel) and PND. Current studies indicate that air pollution may act on PND through oxidative stress and neuroendocrine mechanisms, but the exact biological mechanism remains to be further studied. In the future, further studies should be encouraged on the epidemiological associations of other indoor air pollutants with PND and the interactions between other factors and air pollution on PND, and the underlying biological mechanisms, to provide new insights for the prevention of PND from the perspective of environmental health.

Association between daily average temperature and premature birth in Ningbo City: A time-series analysis / 环境与职业医学

Background Research on the relationship between ambient temperature and preterm birth has received increasing attention, but the conclusions of the previous literature are inconsistent. Objective To explore the impact of environmental temperature exposure in Ningbo on premature delivery of pregnant women. Methods The birth information, preterm birth data, and age of pregnant women from January 2016 to September 2020 were collected by the electronic medical record system of Ningbo Women’s and Children’s Hospital. Meteorological data for the same period were obtained through Ningbo Meteorological Bureau, including daily average temperature, daily average relative humidity, and daily average air pressure. Daily concentrations of SO2, NO2, and PM10 were derived through the air quality real-time release system on the website of Ningbo Environmental Protection Bureau. A distributed lag nonlinear model was used to analyze the impact of environmental temperature on preterm birth by stratifying pregnant women’s age and birth delivery mode. Results The incidence rate of preterm birth in Ningbo from 2016 to 2020 was 5.91%. The exposure-response curve between environmental temperature and preterm birth presented a “U” shape. Taking 22.5 ℃ as a reference, the cumulative effect of 31 ℃ (the 95th percentile) and 32 ℃ (the 99th percentile) over a 21-day lag on preterm delivery was statistically significant, and the related RR (95%CI) values were 1.67 (1.05-2.65) and 1.85 (1.09-3.14) respectively. The results of stratified analysis showed that among pregnant women ≥30 years old, the 21-day cumulative effects of 31 ℃ and 32 ℃ on preterm delivery were statistically significant, and the related RR (95%CI) values were 2.09 (1.08-4.05) and 2.36 (1.11-5.03) respectively; among pregnant women with natural delivery, the 21-day cumulative effect of 32 ℃ on preterm delivery was statistically significant, and the RR (95%CI) was 1.95 (1.02-3.74). Conclusion Exposure of pregnant women to high temperature during pregnancy could increase the risk of preterm birth, and there is a delayed cumulative effect.

Effects of ambient temperature on metabolic syndrome and pathway analysis / 环境与职业医学

Background In recent years, the incidence of metabolic syndrome (MS) is increasing significantly in China. Some studies have found that temperature is related to single metabolic index, but there is a lack of research on associated mechanism and identifying path of the influence of temperature on MS. Objective Based on the data of Guangdong Province, to investigate the effect of temperature on MS and its pathway. Methods A total of 8524 residents were enrolled by multi-stage random sampling from October 2015 to January 2016 in Guangdong. Basic characteristics, behavioral characteristics, health status, and physical activity level were obtained through questionnaires and physical examinations, and meteorological data were obtained from meteorological monitoring sites. We matched individual data both with the temperature data of the physical examination day and of a lag of 14 d. A generalized additive model was used to explore the exposure-effect relationship between temperature and MS and its indexes, calculate effect values, and explore the effects of single-day lag temperature. Based on the literature and the results of generalized additive model analysis, a path analysis was conducted to explore the pathways of temperature influencing MS. Results The association between daily average temperature on the current day or lag 14 day and MS risk was not statistically significant. When daily average temperature increased by 1 ℃, the change values of fasting blood-glucose (FBG), systolic blood pressure (SBP), diastolic blood pressure (DBP), and high density lipoprotein cholesterol (HDL-C) were −0.033 (95%CI: −0.040-−0.026) mmol·L−1, −0.662 (95%CI: −0.741-−0.583) mmHg, −0.277 (95%CI: −0.323-−0.230) mmHg, and −0.005 (95%CI: −0.007-−0.004) mmol·L−1 respectively. The effects of average daily temperature on FBG, blood pressure, HDL-C, and waist circumference lasted until lag 14 day. The effects of daily average temperature on SBP and DBP were the largest on the current day. Daily average temperature of current day had direct and indirect effects on FBG and SBP. Temperature had an indirect effect on TG, and the intermediate variables were waist circumference and FBG, with an indirect effect value of −0.011 (95%CI: −0.020-−0.002). The indirect effects of daily average temperature on SBP, FBG, and TG were weak. Conclusion There is no significant correlation between temperature and risk of MS, and daily average temperature of current day could significantly affected blood pressure and FBG with a lag effect. Daily average temperature of current day has indirect effects on FBG and TG.

Ambient radiation of patients undergoing 18F-FDG PET/CT myocardial metabolism imaging / 中国辐射卫生

Objective To study the ambient radiation of patients undergoing 18F-FDG PET/CT myocardial metabolism imaging, and to provide data for protection of surrounding people against radiation. Methods A total of 33 patients were selected for 18F-FDG PET/CT myocardial metabolism imaging. Dose equivalent rate was measured at the height of patient chest, in different directions, at different time points and at different distances, to investigate the distribution of ambient radiation of the patient. Results At the same time point and distance, the dose equivalent rates at the left and right sides of the patient were lower than the front and back sides. The dose equivalent rate at 1 m in front of the patient was 13-21 μSv/h after 18F-FDG injection, and decreased to 5-14 μSv/h after PET/CT imaging, with a mean decrease of 46%. The ambient dose equivalent rate decreased exponentially with distance (10~300 cm), and the mean power was −1.2. Conclusion The ambient radiation of patients undergoing 18F-FDG PET/CT myocardial metabolism imaging was high after 18F-FDG injection, and the ambient dose equivalent rate decreased rapidly with time and distance. Our results suggest that patients undergoing myocardial metabolism imaging should avoid prolonged and close contact with other people on the day of examination.

Investigation on the radiation of 131I in treatment site of a grade A tertiary hospital / 中国辐射卫生

Objective To detect the radiation of 131I in treatment site of a grade A tertiary hospital. Methods A total of 25 patients with thyroid cancer were administrated 131I at a total dose of 82880 MBq. After administration, the ambient dose equivalent rate of the ward was detected with X- and γ-ray detectors. After patient discharge, surface contamination of the ward was detected with α/β surface contamination meter. During patient hospitalization and on the day of discharge, air samples were collected from 131I treatment site and office area. The air samples were measured using a HPGe γ-ray spectrometer and the concentration of 131I in air was calculated. Results The ambient dose equivalent rate in the ward ranged from 0.15 to 0.46 μSv/h. Before ward cleaning, surface contamination ranged from 0.53 to 40.1 Bq/cm2 and the highest value was recorded on the toilet. Within 4 h after administration, the concentrations of 131I in air in treatment site and the corridor of the office area were 1.74 Bq/m3 and 0.66 Bq/m3, respectively. The ventilation air flow rate in the treatment site was 0.50 m/s. Ventilation decreased the concentration of 131I in air by 29.7%, 79.7%, and 53.3% compared with the previous day during hospitalization and on the day of discharge. Conclusion The radiation of external exposure of 131I in the treatment site is low and the shielding is effective. Before ward cleaning, the surface contamination is lower than the required limits except for the toilet. Ventilation is the primary way to reduce the concentration of 131I in air.

Cooling Kinetic Characteristics of Temperature Difference between Cadaver Temperature and Ambient Temperature / 法医学杂志

OBJECTIVES@#To study the cooling reaction kinetic characteristics of the temperature difference between cadaver temperature and ambient temperature (hereinafter referred to as "cadaver temperature difference") according to the reaction kinetics method.@*METHODS@#Thirty rabbits were randomly divided into 5 groups with 6 rabbits in each group. The rabbits were injected with 10% potassium chloride solution intravenously. After death, the rabbits were placed at 5 ℃, 10 ℃, 15 ℃, 20 ℃ and 25 ℃ environment condition, respectively, and the rectal temperature was measured every minute for 20 hours. The measured cadaver temperature was subtracted from ambient temperature, and the cadaver temperature difference data was calculated using the reaction kinetics formula. The linear regression equation was fitted for analysis, and the experimental results were applied to the temperature difference data of human body after death for verification.@*RESULTS@#Under different environmental conditions, the linear coefficient determination of temperature difference -ln(C/C0) in rabbits was 0.99, showing a good linear relationship with time t. The application of human body temperature data after death was consistent with the results of animal experiments.@*CONCLUSIONS@#Under stable conditions, the temperature difference cooling process after death in rabbits is a first-order kinetic response. The method can also be used to study the temperature difference in human body after death.

Application of micro-pen electrospray ionization tandem mass spectrometry in rapid detection of metabolic stability of testosterone and dextromethorphan / 药学学报

Probe electrospray ionization (PESI) is one of the typical types of ambient ionization technology, but its application in quantitative analysis is limited due to its poor sampling stability. Previously, we developed a new micro-pen electrospray ionization tandem mass spectrometry (μPen-ESI-MS/MS) method based on PESI. In this study, a μPen-ESI-MS/MS method to measure testosterone and dextromethorphan in liver microsome samples was developed and validated to further applicate in evaluating drug metabolism stability and CYP450 enzyme activity. A μPen-ESI-MS/MS method for detecting the CYP3A4 substrate testosterone and CYP2D6 substrate dextromethorphan in the liver microsome incubation system were developed, and the linearity, precision and accuracy of the method was validated. The validated method was further used to detect the metabolic stability of testosterone in the liver microsome incubation system. The results showed that the μPen-ESI-MS/MS had high efficiency with 0.3 min spraying time of each sample. The standard curve of the testosterone and dextromethorphan has good linearity (R2 > 0.99), the intra- and inter-batch accuracy of testosterone and dextromethorphan was 95.9%-109.3% and 90.5%-107.3%, respectively; the intra- and inter-batch precision was acceptable with RSD values of 2.4%-13.5% and 3.4%-12.1%. The half-lives of testosterone and dextromethorphan in the liver microsome incubation system were 12 min and 14 min, respectively. This study provided a rapid and sensitive μPen-ESI-MS/MS method for the assay of testosterone and dextromethorphan in liver microsome samples, and provided a new strategy for the evaluation of drug metabolism stability and CYP3A4/CYP2D6 activity.