Objective To analyze the current situation of depressive symptoms among medical staff in Beijing City and its correlation with symptoms of anxiety, occupational stress and insomnia. Methods A total of 2 687 medical staff from 28 medical institutions in eight municipal districts of Beijing City were selected as study subjects using multi-stage sampling method. The basic situation, depression symptoms, anxiety symptoms, occupational stress and insomnia symptoms were investigated using the National Occupational Health Literacy Monitoring Questionnaire for Key Groups, Patient Health Questionaire-9, 7-item Generalized Anxiety Disorder Scale, Core Occupational Stress Scale, and Self-Sleep Management Questionnaire. Results The detection rate of depressive symptoms was 28.3%, and the detection rates of moderate, moderate-severe and severe depressive symptoms were 18.9%, 6.9% and 2.5%, respectively. The detection rate of anxiety symptoms was 41.3%, and the detection rates of mild, moderate and severe anxiety symptoms were 29.7%, 7.7% and 3.9%, respectively. The detection rate of occupational stress was 26.7%. The detection rate of insomnia symptoms was 36.6%. The results of multivariate logistic regression analysis showed that the risk of depressive symptoms in male medical staff was higher than that in female (P<0.05). The risk of depressive symptoms in night shift staff was higher than that in staff without night shift (P<0.05). The more severe the anxiety symptoms, the higher the risk of depressive symptoms (all P<0.01). The risk of depressive symptoms in medical staff with occupational stress was higher than those without occupational stress (P<0.01). The risk of depressive symptoms in medical staff with insomnia symptoms was higher than those without insomnia symptoms (P<0.01). Conclusion The detection rate of depressive symptoms among medical staff in Beijing City is relatively high. Gender, night shift, anxiety symptoms, occupational stress, and insomnia symptoms were independent risk factors of depressive symptoms.

Plastics have brought invaluable convenience to human life since it was firstly synthesized in the last century. However, the stable polymer structure of plastics led to the continuous accumulation of plastic wastes, which poses serious threats to the ecological environment and human health. Poly(ethylene terephthalate) (PET) is the most widely produced polyester plastics. Recent researches on PET hydrolases have shown great potential of enzymatic degradation and recycling of plastics. Meanwhile, the biodegradation pathway of PET has become a reference model for the biodegradation of other plastics. This review summarizes the sources of PET hydrolases and their degradation capacity, degradation mechanism of PET by the most representative PET hydrolase-IsPETase, and recently reported highly efficient degrading enzymes through enzyme engineering. The advances of PET hydrolases may facilitate the research on the degradation mechanism of PET and further exploration and engineering of efficient PET degradation enzymes.
Humans ; Hydrolases/metabolism* ; Polyethylene Terephthalates/metabolism* ; Plastics/metabolism* ; Ethylenes

Objective:To investigate the ethics and existing problems of experimental animals in medical experiments and experimental teaching, and to formulate countermeasures so that animal ethics and animal welfare can be truly reflected in medical experiments.Methods:In this study, a "Basic Function Experiment Center Animal Experiment Questionnaire" with 25 questions was formulated from three aspects: the ethical cognition of experimental animals, whether animal experiments are ethical or not, how to view the problems of animal ethics and experimental teaching and the cognition of virtual simulation experiment teaching. Questionnaire was sent to Hubei University of Medicine to investigate the international students of Batch 2017 (5-year program), undergraduates of Batch 2017 (5-year program) and nursing students of Batch 2018 (4-year program) as well as teachers, researchers and employees of laboratory animal center (all with bachelor degree or above). The survey results were expressed as percentage.Results:The recovery rate of the questionnaire in this study was 98.04%(2 451/2 500), among which the practitioners, teachers and researchers in the laboratory animal center clearly understood the ethics of experimental animals, but there was a widespread phenomenon of lagging ethics among the students. For example, 16.24% (398/2 451) students had not received animal experiment ethics education and training, 29.46% (722/2 451) were not clear about animal protection laws and regulations, 7.14% (175/2 451) thought animal experiments were immoral; 29.54% (724/2 451) had vague cognition of animal welfare and ethical knowledge; 25.91% (635/2 451) were not familiar with the operation steps; 9.38% (230/2 451) were indifferent to the extra treatment of animals due to operation errors, 7.83% (192/2 451) chose to give up the experiment in the treatment of animals after massive bleeding, only 5.43% (133/2 451) chose to continue the experiment after timely hemostasis and infusion, and 9.26% (227/2 451) chose to do operations unrelated to the experiment. After the experiment, 2.28% (56/2 451) chose to kill the animals by bloodletting, only 5.51% (135/2 451) chose excessive anesthesia euthanasia, and 1.96% (48/2 451) chose to kill the animals by cervical dislocation and violence. Only 15.79% (387/2 451) chose to remember the dead animal for 2 minutes. Only 32.56%(798/2 451) of the respondents understood virtual simulation experiment, 34.92% (856/2 451) of the respondents thought that virtual simulation experiment or experimental teaching video could be used to replace the existing live animal experiment, 77.56% (1 901/2 451) believed that the construction of virtual simulation laboratory should be strengthened.Conclusion:It is imperative to strengthen the education of students' ethics of experimental animals, which is conducive to the establishment of correct ethics of experimental animals for medical students, so that the "3R" principle and animal welfare can be truly implemented in experimental teaching and scientific research experiments.

Algae are a large group of photosynthetic organisms responsible for approximately half of the earth's total photosynthesis. In addition to their fundamental ecological roles as oxygen producers and as the food base for almost all aquatic life, algae are also a rich source of bioactive natural products, including several clinical drugs. Cytochrome P450 enzymes (P450s) are a superfamily of biocatalysts that are extensively involved in natural product biosynthesis by mediating various types of reactions. In the post-genome era, a growing number of P450 genes have been discovered from algae, indicating their important roles in algal life-cycle. However, the functional studies of algal P450s remain limited. Benefitting from the recent technical advances in algae cultivation and genetic manipulation, the researches on P450s in algal natural product biosynthesis have been approaching to a new stage. Moreover, some photoautotrophic algae have been developed into "photo-bioreactors" for heterologous P450s to produce high-value added pharmaceuticals and chemicals in a carbon-neutral or carbon-negative manner. Here, we comprehensively review these advances of P450 studies in algae from 2000 to 2021.

Struma ovarii is a highly specialized form of monoderal ovarian teratoma, in which thyroid tissue has exceeded all other tissues or only thyroid tissue malignant struma ovarii is a very rare disease. Studies have confirmed that the pathogenesis is basically consistent with primary thyroid cancer. Preoperative diagnosis is difficult and the diagnosis should be based on postoperative paraffin pathology. It’s important to emphasize that the histologic malignance does not represent malignant ovarian behavior. Transabdominal hysterectomy+bilateral salpingo-oophorectomy has a better prognosis, and there are different opinions on the management of the mainstream thyroid. Most patients take active thyroid excision followed by chemotherapy and radiotherapy and 131I for postoperative follow-up in accordance with the principle of primary thyroid cancer.

Objective:To study the epidemic status of drinking tea type endemic fluorosis in Qinghai Province.Methods:In 2019, in counties (cities, districts, referred to as counties) that had the habit of drinking brick tea in 8 cities (prefectures) of Qinghai Province, epidemiological investigation of drinking tea type endemic fluorosis was carried out in villages. Ten households were randomly selected from each village, to investigate the demographic data of each household and the drinking situation of brick tea, residents' drinking water and brick tea samples were collected to determine the fluorine content, and calculate the daily per capita tea fluorine intake. At the same time, skeletal fluorosis was examined in all adults over 25 years old, and dental fluorosis was examined in all children aged 8 to 12 years old in survey sites. The content of fluorine in tea and water was detected by ion selective electrode method; the diagnosis of skeletal fluorosis was based on "Diagnostic Criteria for Endemic Skeletal Fluorosis" (WS 192-2008), the diagnosis of dental fluorosis was based on "Diagnosis of Dental Fluorosis" (WS/T 208-2011).Results:The mean (range) of fluorine of the 3 602 water samples was 0.31 (0.20 - 1.00) mg/L. The geometric mean (range) of fluorine of the 31 067 brick tea samples was 646 (40 - 2 295) mg/kg, the fluorine content of the brick tea ≤300 mg/kg accounted for 7.80% (2 422/31 067) of the total samples. The proportion of drinking Fu brick-tea was 89.97% (27 952/31 067); and the daily per capita tea fluorine intake was 1.93 mg, the daily per capita tea fluorine intake in Guoluo, Yushu and Hainan prefectures were higher than the health standard (3.50 mg). The detection rate of skeletal fluorosis in adults was 0.16% (2 357/1 484 907), Yushu Prefecture was the highest [29.23% (592/2 025)], followed by Guoluo Prefecture, which was 8.21% (771/9 393). The detection rate of dental fluorosis in children was 4.79% (8 076/168 623), Yushu Prefecture was the highest [32.61% (1 562/4 790)].Conclusion:Drinking tea type endemic fluorosis is prevalent in Qinghai Province, with obvious regional characteristics, covering a large population. The disease is relatively popular in Yushu Prefecture and Guoluo Prefecture.

Coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has spread around the world. However, approaches to distinguish COVID-19 from pneumonia caused by other pathogens have not yet been reported. We retrospectively analyzed the clinical data of 97 children with probable COVID-19. A total of 13 (13.4%) patients were confirmed positive for SARS-CoV-2 infection by nucleic acid RT-PCR testing, and 41 (42.3%) patients were found to be infected with other pathogens. Notably, no pathogen was detected in 43 (44.3%) patients. Among all patients, 25 (25.8%) had familial cluster exposure history, and 52 (53.6%) had one or more coexisting conditions. Fifteen (15.5%) patients were admitted or transferred to the PICU. In the 11 confirmed COVID-19 cases, 5 (45.5%) and 7 (63.6%) were positive for IgM and IgG against SARS-CoV-2, respectively. In 22 patients with suspected COVID-19, 1 (4.5%) was positive for IgG but negative for IgM. The most frequently detected pathogen was Mycoplasma pneumonia (29, 29.9%). One patient with confirmed COVID-19 died. Our results strongly indicated that the detection of asymptomatic COVID-19 or coexisting conditions must be strengthened in pediatric patients. These cases may be difficult to diagnose as COVID-19 unless etiologic analysis is conducted. A serologic test can be a useful adjunctive diagnostic tool in cases where SARS-CoV-2 infection is highly suspected but the nucleic acid test is negative.
Age Factors ; COVID-19/diagnosis* ; COVID-19 Testing ; Child ; Child, Preschool ; China ; Female ; Hospitalization ; Humans ; Infant ; Male ; Retrospective Studies ; SARS-CoV-2/isolation & purification* ; Symptom Assessment

Objective: To analyze the epidemiological characteristics of acute paraquat(PQ)poisoning in children in southwest Shandong, and the risk factors for pulmonary interstitial fibrosis. Methods: This retrospective study was performed on the clinical data of children with acute PQ poisoning admitted from January 2013 to December 2017 in 12 hospitals in southwest Shandong.All participants were divided into pulmonary interstitial fibrosis group and no pulmonary interstitial fibrosis group on the basis of the chest CT 14 days after poisoning.The epidemiological characteristics and risk factors of pulmonary interstitial fibrosis were analyzed. Results: During the study period, a total of 307 children with acute PQ poisoning were admitted to 12 hospitals, of which 61 (19.87%) were suffering from acute PQ poisoning.Forty-nine cases with complete clinical data were analyzed, including 26 male and 23 female patients poisoned by oral.The age distribution ranged from 8 months to 14 years.Poisoning mainly occured from July to September of each year.The mortality of acute PQ poisoning was 8.2%(4/49), and the incidence of pulmonary interstitial fibrosis in survival patients was 44.4%(20/45). Statistical differences (P<0.05) were found between the pulmonary interstitial fibrosis and no pulmonary interstitial fibrosis, with regard to the times of blood purification, the time from poison exposure to blood purification, the application rate of glucocorticoids, the concentration of PQ in urine, the pediatric critical illness score, the time from poison exposure to gastric lavage, the white blood count at admission, serum creatinine, arterial blood lactate, PaO₂, PaCO₂, and PaO₂/FiO₂; however, there was no significant difference in the proportion of blood purification treatment, the mode of blood purification treatment, alanine aminotransferase, aspartate aminotransferase, urea nitrogen, creatine kinase and troponin.Stepwise logistic regression analysis showed that the time from exposure to poison to gastric lavage(OR=0.683, 95%CI 0.210-2.222)and to blood purification(OR=0.0133, 95%CI 0.004-0.042), the times of blood purification(OR=2.862, 95%CI 1.450-5.648), concentration of PQ in urine(OR=1.435, 95%CI 1.085-1.898), and the use of glucocorticoids(OR=0.190, 95%CI 0.048-0.757) were the risk factors for pulmonary interstitial fibrosis(P<0.05). Conclusion Early gastric lavage and blood purification, increasing the frequence of adminitrating purification appropriately, using low-dose glucocorticoids can reduce the incidence of pulmonary interstitial fibrosis of children with acute PQ poisoning.

Objective To explore the prevalence state of drinking brick-tea type fluorosis in children in Guoluo Prefecture,Qinghai Province.Methods According to the historical prevalence of drinking tea-type fluorosis in Guoluo Prefecture,in 2017,in 5 counties of Guoluo Prefecture,according to the pastoral area,agricultural area,semi-agricultural and semi-pastoral areas,each township (town) was selected,in each township (town) drawed a natural village in a ward as a survey point.At each survey site,drinking water samples of local residents were collected,and 10 households were selected,tea samples were collected,and dental fluorosis was investigated for children aged 8-12 years old.The mean of fluoride was determined by fluoride ion selective electrode method (GB/T 5750.5-2006,GB 19965-2005),and the dental fluorosis was diagnosed based on "Diagnosis of Dental Fluorosis" (WS/T 208-2011).Results The mean of fluoride in 85 water samples was 0.34 mg/L (0.20-0.77 mg/L),the mean of fluoride in 161 brick-tea samples was 579 mg/kg (110-1 278 mg/kg).The mean of daily fluoride intake of each person was 6.78 mg,among them,73.29％ (118/161) drank brick-tea,the detection rate of dental fluorosis of 2 083 children was 22.85％ (476/2 083),and the index of dental fluorosis was 0.42,the prevalence was weak.Conclusion The prevalence of drinking brick-tea type fluorosis of children in Guoluo Prefecture is less serious.

Objective To analyze the operation of water improvement projects in drinking water-borne fluorosis areas of Qinghai Province and the trend of dental fluorosis in children aged 8 to 12 years, and to evaluate the effects of prevention and control measures comprehensively, so as to provide basis for improving prevention and control strategies. Methods In 2009 - 2017, according to the "Qinghai Drinking Water Endemic Fluorosis Surveillance Program", four project counties of Huangyuan, Minhe, Hualong and Guide were selected in Qinghai Province. Three villages in each project county were selected according to their mild, moderate and severe conditions, and monitored the operation of water improvement projects, water fluoride content and dental fluorosis among children aged 8 to 12-year-old in each diseased village. Results In 2009-2017, the normal operation rate of water improvement projects increased from 2/8 to 7/8; the batch operation rate of the projects decreased from 5/8 to 1/8; the number of abandoned projects decreased from 1 to 0; the number of people covered by qualified water fluoride increased from 9962 to 80760 people; there was no significant difference in water fluoride content between different years (F = 0.758, P > 0.05). The total detection rate of children's dental fluorosis was 33.01％(1812/5489) from 2009 to 2017, the index of dental fluorosis was 0.65, and the epidemic intensity was slightly prevalent;the detection rate of children's dental fluorosis was 30.02％(951/3168) in villages with normal operation of water improvement projects and qualified water fluoride content, the index of dental fluorosis was 0.58, and the epidemic intensity was marginal;the detection rate of children's dental fluorosis was 32.72％(583/1782) in villages with abnormal operation of water improvement projects or excessive fluoride, the index of dental fluorosis was 0.66, and the epidemic intensity was slight; the detection rate of children's dental fluorosis in villages without changing the water was 51.58％ (278/539), and the index of dental fluorosis was 1.04, belonging to the moderate epidemic intensity; the detection rate of children's dental fluorosis in villages without changing the water was significantly higher than that in villages with normal operation of water improvement projects and qualified water fluoride content (χ2 = 102.30, P < 0.01). Conclusions The water improvement project in drinking water-borne fluorosis areas is running well and the operation rate is increasing year by year. The detection rate of dental fluorosis in children aged 8-12 years old in villages with normal operation of water improvement projects and qualified water fluoride content was significantly lower than that in villages without changing the water. The monitoring of fluorosis and the maintenance of water-renovation projects should be strengthened, and the problem of drinking water for residents in villages without changing the water should be resolved as soon as possible.