Systematic characterization and identification of the chemical constituents of the Schisandra chinensis decoction based on a hybrid scanning technique of UHPLC/IM-QTOF-MS / 药学学报

italic>Schisandra chinensis is a traditional Chinese medicine with the functions of reinforcing deficiency, strengthening, and inducing astringency, appliable to treat the chronic cough and deficiency in breath, palpitation, and insomnia, etc. A hybrid mass spectrometry scanning strategy (high-definition data-independent/data-dependent acquisition, HDDIDDA), enabling the ion mobility separation and alternating data-independent acquisition/data-dependent acquisition, was established, which, in combination with in-house library-driven automatic peak annotation workflows facilitated by the UNIFI software, was utilized to systematically characterize the multi-classes of chemical components from S. chinensis. The use of an HSS T3 column (100 mm × 2.1 mm, 1.8 μm), 0.1% formic acid in H2O-acetonitrile as the mobile phase running at the flow rate of 0.3 mL·min-1, and column temperature at 35 ℃, could enable good separation of the S. chinensis components within 42 min. HDDIDDA scan in both the positive and negative ion modes was employed for data acquisition. Based on the automatic peak annotation, reference standards comparison, MS2 data interpretation, and literature analysis, we were able to identify or tentatively characterize 105 compounds in the S. chinensis decoction, involving 56 terpenoids, 42 lignans, five glycosides, one organic acid, and one flavonoid. HDDIDDA scanning can improve the coverage of data acquisition and improve the accuracy of identification, while CCS prediction analysis provides the possibility to distinguish isomers by the ion mobility technology. The results provide reference for the intelligent material basis research of TCM.

Application of Pentacam TNP in calculating the intraocular lens power after corneal refractive surgery / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To assess the accuracy of predicting intraocular lens(IOL)power after myopic refractive surgery using the Pentacam system's true net power(TNP)in the 3 mm zone combined with the SRK/T formula [i.e. TNP 3 mm(SRK/T)].METHODS: Retrospective study. This study enrolled 35 cases(50 eyes)of patients undergoing cataract surgery after laser assisted in situ keratomileusis(LASIK)or photorefractive keratectomy(PRK)from July 2019 to December 2021. Preoperatively, IOL power of 50 eyes, 34 eyes and 41 eyes was calculated by TNP 3 mm(SRK/T), Barrett True-K and Olsen 2 formulas, respectively, with at least 2 formulas used to calculate IOL power for each patient. The actual diopter was recorded 3 mo postoperatively. Prediction errors(PE)of IOL power were compared among the three calculation methods, and the proportion of eyes with PE within ±0.5 D and ±1.0 D was analyzed.RESULTS: The PE at 3 mo postoperatively for TNP 3 mm(SRK/T), Barrett True-K, and Olsen 2 was -0.02±0.63, -0.54±0.80, and 0.25±0.80 D, respectively(P<0.001). The proportions of PE within ±0.5 D were 66%(33/50), 44%(15/34)and 37%(15/41), respectively(P<0.05); the proportions of PE within ±1.0 D were 88%(44/50), 71%(24/34)and 80%(33/41), respectively(P>0.05).CONCLUSION: The Pentacam TNP 3 mm(SRK/T)method is simple to operate and provides accurate calculation of IOL power after corneal refractive surgery.

Systematic analysis of MYB transcription factors related to the geniposide biosynthesis in Gardenia jasminoides Ellis based on whole genome / 药学学报

MYB transcription factors are involved in the regulation of various secondary metabolites biosynthesis. Gardenia jasminoides Ellis is the commonly used Chinese herbal medicine, and its main active ingredient is geniposide. Here, leaves and flower buds at different developmental stages of G. jasminoides were used to explore MYB transcription factors related to geniposide biosynthesis based on genome and transcriptome analysis. Transcriptome data analysis showed that, different from the expression of the common pathway genes for terpenoid biosynthesis, the expression level of genes in the specific pathway of geniposide biosynthesis was significantly higher in flower buds than in leaves, which was the same as the organ accumulation pattern of this component. And the promoter regions of geraniol synthase, iridoid synthase and geniposidic acid methyltransferase involved in the specific pathway all contained multiple MYB-binding sites. A total of 105 MYB transcription factors were obtained by annotating the coding genes of G. jasminoides, which were divided into 68 1R-MYB, 33 R2R3-MYB, 3 3R-MYB and 1 atypical MYB transcription factor according to the number of conserved domain. Based on the analysis of phylogenetic tree and quantitative real-time PCR, three candidate MYB transcription factors related to geniposide biosynthesis were selected, including potential positive regulation factor GjMYB23 and negative regulation factors GjMYB31 and GjMYB73. The results of this study will lay a foundation for searching the regulation of geniposide biosynthesis and further analysis of the quality formation mechanism of G. jasminoides, so as to promote the breeding of excellent varieties of G. jasminoides.

Principles and strategies for species identification based on analysis of whole-genome / 药学学报

The main sources of natural drugs include various biological species such as plants, animals, and microorganisms. The accurate identification of these species is the bedrock of natural drug development. We propose a novel method of species identification in this paper: analysis of whole-genome (AGE), a molecular diagnostic method used to identify species by finding species-specific sequences from the whole genome and precisely recognizing the specific target sequences. We elaborate that the principle for species identification based on AGE is that the genome sequences of diverse species must differ and divide the implementation strategy of the method into two levels of research and application. Based on our analysis of its characteristics, the method would have the potential advantages of reliable principle, high specificity, and wide applicability. Moreover, three crucial concerns related to building method systems including genome acquisition, bioinformatics analysis, and database construction, are further discussed. In summary, we offer theoretical underpinnings and methodological guidance for the development of bioinformatics software and commercial kits, indicating AGE has great application potential in objects, subjects, and industries.

Antiarrhythmic active components in traditional Chinese medicine acting on potassium channels / 中国中药杂志

Arrhythmia is an external manifestation of cardiac electrophysiological disorder. It exists in healthy people and patients with various heart diseases, which is often associated with other cardiovascular diseases. The contraction and diastole of myocardium are inseparable from the movement of ions. There are many ion channels in the membrane and organelle membrane of myocardium. The dynamic balance of myocardial ions is vital in maintaining myocardial electrical homeostasis. Potassium ion channels that have a complex variety and a wide distribution are involved in the whole process of resting potential and action potential of cardiomyocytes. Potassium ion channels play a vital role in maintaining normal electrophysiological activity of myocardium and is one of the pathogenesis of arrhythmia. Traditional Chinese medicine(TCM)has unique advantages in treating arrhythmia for its complex active components and diverse targets. A large number of TCM preparations have definite effect on treating arrhythmia-related diseases, whose antiarrhythmic mechanism may be related to the effect on potassium channel. This article mainly reviewed the relevant studies on the active components in TCM acting on different potassium channels to provide references for clinical drug use and development.

Determination of two isomers of tetrachloroethane by solvent desorption-gas chromatography in workplace air / 中国职业医学

Objective: To establish a solvent desorption-gas chromatography method for the determination of 1,1,2,2-tetrachloroethane and 1,1,1,2-tetrachloroethane in workplace air. Methods: The 1,1,2,2-tetrachloroethane and 1,1,1,2-tetrachloroethane in workplace air were collected using activated carbon tubes, desorbed with carbon disulfide, and separated and detected by gas chromatography. The quantifications were based on standard curves. Results: The linear ranges of 1,1,2,2-tetrachloroethane and 1,1,1,2-tetrachloroethane were 0.98-395.50 and 0.87-395.50 mg/L, respectively, with the correlation coefficient of 0.999 95. The detection limits were 0.29 and 0.26 mg/L, respectively. The average of desorption efficiency was 92.04%-104.67%. The within- and between-run relative standard deviations were 1.42%-2.09% and 1.63%-6.09%, respectively. The sampling efficiency was more than 98.00%. The samples could be stored at room temperature for at least 14 days. Conclusion: This method can be used in detection of 1,1,2,2-tetrachloroethane and 1,1,1,2-tetrachloroethane in workplace air.

Determination of dimethyl carbonate in workplace air by solvent desorption-gas chromatography / 中国职业医学

Objective: To establish a solvent desorption-gas chromatography method for determination of dimethyl carbonate (DMC) in workplace air. Methods: The air samples were collected using activated carbon tubes, desorbed by carbon disulfide, separated by dimethylpolysiloxane capillary columns, and detected by a flame ionization detector. Results: The linear range of DMC was 2.14 to 1.07×104 mg/L, and the correlation coefficient was greater than 0.999. The detection limit was 0.14 mg/L, the lower limit of quantification was 0.47 mg/L, the minimum detection concentration was 0.10 mg/m3, and the minimum quantification concentration was 0.32 mg/m3 (based on 1.5 L workplace air). The average desorption efficiency of the method was 96.2% to 102.0%. Both the within-run and between-run relative standard deviations were 0.9% to 2.3%. The samples could be stored for at least seven days at four celsius degree. Conclusion: This method shows high desorption efficiency, high sensitivity, good precision and is simple in using. It can be used for the determination of DMC in workplace air.

Analysis of satisfaction and influencing factors of scientific research incentive mechanisms for young medical staff in a children′s hospital in Beijing / 中华医学科研管理杂志

Objective:This study aims to explore the satisfaction and influencing factors of scientific research incentive mechanisms for young medical staff in a children′s hospital in Beijing, and to provide references for the management department to develop relevant incentive strategies.Methods:A satisfaction questionnaire survey of scientific research incentive mechanisms was carried out during April and May, 2022. Collected data were analyzed by rank sum test and ordered logistic regression.Results:The level of overall satisfaction of 339 young medical staffs was 81.42%. The satisfaction rate of incentive factors was 80.50% and hygiene factors was 77.51%.According to the findings, there were significant differences in educational backgrounds, professional titles and job types, hygiene factors, and incentive factors ( P<0.05). The contributing factors of the job satisfaction were professional title, hygiene factors and incentive factors. Conclusions:The overall satisfaction with the incentive work of the young research staff surveyed was relatively at high-level. It is necessary to improve tailed hygiene factors to meet the characteristics young medical staff, such as setting up full-time scientific research working hours, exploring the establishment of diversified of scientific research sharing mechanisms to increase the utilization of the scientific research platform. It is important to enhance incentive factors to establish a long-term incentive mechanism for young personnel, such as setting up interdisciplinary research projects, exploring the establishment of a recommendation mechanism for outstanding young talents, in order to provide them with more opportunities for further intensive training.

Optimization practice of youth research project management in children′s hospital: Based on the situation and demand of National Natural Science Youth Foundation in Beijing Children′s Hospital / 中华医学科研管理杂志

Objective:The study takes the Youth Research Project of National Natural Science Foundation of China (NSFC) as an example, analyzes the development and management optimization strategy of such research project in a children′s hospital, to provide reference for the training of pediatric young talents.Methods:Personnel interview and questionnaire survey were adopted to analyze the common characteristics of project application and approval, trend of change, demand and bottleneck challenges of the NSFC Youth Research Project from 2016 to 2022.Results:The total number of approved project were increasing while the rate of the bids fluctuated, and the distribution of department, gender and age are not balanced, full-time scientific research personnel, male, young age and other factors have the advantages of being approved. Five influential factors, including scientific research accomplishment, supporting conditions, research foundation, methods & skills, and scientific research atmosphere and environment, were identified as necessary components of getting funded. The survey also founded that two thirds of the needs run through the whole application process that from the topic selection, nurtured seed-funding, team-building and proposal development.Conclusions:This study puts forward a management plan for youth scientific research projects in children′s hospital from three aspects that including hospital, department and individual. The management department should strengthen the transformation from " full application" to " effective application" , at the same time, more attention should be paid to the selection, training and resource allocation to further optimize the training strategy of youth talents.

Long non-coding RNA C2dat1 involved in diabetic renal interstitial fibrosis by influencing CaMK2D/NF-κB signaling pathway / 中华微生物学和免疫学杂志

Objective:To study the changes in long non-coding RNA C2dat1 expression in kidney tissues of rats at different stages of diabetic kidney disease (DKD) and its relationship with renal interstitial fibrosis.Methods:Forty-eight male SD rats were randomly divided into two groups with 24 rats in each group: control group and DKD group. The rats in the control group were fed with ordinary diet, while those in the DKD group were fed with high-fat diet and drank water freely. After eight weeks of feeding, the rats were fasted for 12 h with free access to water. Then, the DKD group was given a one-time intrabitoneal injection of streptozotocin and the control group was given an equal dose of sodium citrate buffer. After 72 h, the random peripheral blood glucose concentration (≥ 16.7 mmol/L for three consecutive days) and urine sugar (positive) were tested to assess the establishment of the diabetes model. Urine, blood and kidney samples were collected at 3, 6, 9 and 12 weeks. The urinary protein excretion rate within 24 h, urinary creatinine and serum total cholesterol were measured by automatic biochemical apparatus. Pathological changes in kidney tissues were observed by HE staining. The expression of calcium/calmodulin-dependent protein kinase Ⅱ delta (CaMK2D), p65, p50, α-SMA and E-cardherin was detected by immunohistochemistry. Quantitative real-time PCR (qPCR) was used to detect the expression of lncRNA C2dat1 and CaMK2D. The relationship of lncRNA C2dat1 with α-SMA, E-cardherin and CaMK2D was analyzed by correlation analysis. In in vitro experiment, renal tubular epithelial cells HK-2 were induced by high glucose. The expression of lncRNA C2dat1 and CaMK2D in HK-2 cells was detected by qPCR after 24, 48 and 72 h of intervention. Results:The rats in the DKD group showed typical symptoms such as polydipsia, polyphagia, significant weight loss and increased blood glucose as compared with the rats in the control group. Results of the biochemical tests revealed that compared with the control group, the DKD group had increased 24 h excretion rate of urinary protein, decreased urinary creatinine and up-regulated total cholesterol. HE staining showed that the rats in the control group had intact glomeruli, normal basement membrane and no mesangial hyperplasia or inflammatory cell infiltration. However, enlarged glomeruli and evenly thickened basement membrane were observed in the DKD group. Immunohistochemistry indicated that the expression of CaMK2D, p50 and α-SMA was higher in the DKD group than in the control group, while the expression of E-cardherin was lower in the DKD group. qPCR results showed that the expression of lncRNA C2dat1 and CaMK2D at mRNA level was higher in the DKD group than in the control group. In in vitro experiment, the expression of lncRNA C2dat1 and CaMK2D at mRNA level was also higher in HK-2 cells induced by high glucose than in the control group. Correlation analysis indicated that lncRNA C2dat1 was positively correlated with α-SMA and CaMK2D, but negatively correlated with E-cardherin. Conclusions:During the progression of DKD, the high expression of lncRNA C2dat1 might promote diabetic renal interstitial fibrosis by regulating the expression of CaMK2D to activate the NF-κB signaling pathway.

Observational study on improvement of hypotension in hemodialysis with blood volume feedback control system / 中华肾脏病杂志

Objective:To study the effect of blood volume feedback control system on improving intradialytic-hypotension (IDH) in maintenance hemodialysis (MHD) patients.Methods:It was a prospective cohort study. Thirty MHD patients with recurrent IDH in the Dialysis Center of the First Affiliated Hospital of Zhejiang University School of Medicine from March 2021 to March 2022 were selected. A self-control study was conducted in MHD patients. The patients were treated with routine hemodialysis in both baseline phase (A1) and reversal phase (A2), while with hemodialysis under the blood volume feedback control system in intervention phase (B). Each phase lasted for 4 weeks (12 hemodialysis sessions). The average occurrences of IDH and IDH-related adverse events (IDH-RAE, stopping dehydration for more than 10 minutes or getting off the hemodialysis machine 10 minutes earlier due to IDH) of each patient between phase A1, B, and A2 were calculated and compared. In a total of 1 080 dialysis records, a logistic regression analysis model was established with age, sex and intervention as independent variables and with the occurrence of IDH-RAE as the outcome.Results:A total of 30 eligible patients were included in the study, including 14 males (46.7%) and 16 females (53.3%), aged 63.0 (56.5, 72.5) years old, with a median dialysis age of 84.0 (37.2, 120.0) months. The average times of IDH in 30 MHD patients decreased from 1.17 (0.83, 1.67) in stage A1 (before intervention) to 0.33 (0.25, 0.58) in stage B (after intervention) ( P<0.05). The frequency of IDH-RAE decreased significantly from 0.29 (0.19, 0.47) in stage A1 to 0.17 (0,0.25) in stage B ( P<0.05). Logistic regression analysis results indicated that the use of blood volume feedback control system reduced the risk of IDH-RAE by 53% ( OR=0.47, 95% CI 0.34-0.64, P<0.001). Conclusions:The application of blood volume feedback control system can effectively reduce the occurrences of IDH and the risk of IDH-RAE in MHD patients.

Association of lean tissue index with arteriovenous fistula dysfunction in maintenance hemodialysis patients / 中华肾脏病杂志

The clinical data of maintenance hemodialysis (MHD) patients from twenty hemodialysis centers in Guizhou province from June to September 2020 were collected by cross-sectional study. The patients were divided into AFD group and non-AFD group according to whether AFD had occurred. LTI was measured by body composition monitor. The results showed that the incidence of AFD in 2 781 MHD patients was 30.0% (835/2 781). Median LTI level was 15.2 (13.2, 17.5) kg/m 2. The LTI level in the AFD group was higher than that in the non-AFD group ( P < 0.05). According to the tertiles of LTI, low LTI group (LTI ≤ 13.9 kg/m 2) had the highest incidence of AFD (35.5%, 334/940), and the high LTI group had the lowest incidence of AFD (26.3%, 241/916), and the difference among the three groups was statistically significant ( χ2=20.182, P < 0.001). Multivariate logistic regression analysis showed that low LTI group as the reference, the risk of AFD in moderate LTI group (13.9 kg/m 2 < LTI ≤ 16.6 kg/m 2) and high LTI group were associated with the 20.0% ( OR=0.800, 95% CI 0.650-0.986, P=0.036) and 22.8% ( OR=0.772, 95% CI 0.616-0.966, P=0.024) decrease, respectively. These results suggest that low LTI level is independently associated with an increased risk of AFD in MHD patients.

Cost-effectiveness analysis of long-acting versus short-acting recombinant human granulocyte stimulating factor in the treatment of III° and IV° bone marrow suppression after chemotherapy / 中国基层医药

Objective:To investigate the cost-effectiveness of long-acting versus short-acting recombinant human granulocyte stimulating factor in the treatment of III° and IV° bone marrow suppression after chemotherapy. Methods:The data of patients who presented with III and IV° bone marrow suppression after chemotherapy and received treatment with recombinant human granulocyte stimulating factor from January 2018 to December 2019 were collected. These patients were divided into the short-acting recombinant human granulocyte stimulating factor group (rhG-CSF group) and the long-acting recombinant human granulocyte stimulating factor group (PEG-rhG-CSF group) group. Clinical efficacy, the incidence of adverse reactions, and cost-effectiveness were compared between the two groups.Results:There were 88 patients, aged (63.97 ± 11.64) years, in the rhG-CSF group. There were 80 patients, aged (63.26 ± 9.09) years in the PEG-rhG-CSF group. There was no significant difference in baseline data between the two groups ( P > 0.05). Total response rate was 72.72% (64/88) in the rhG-CSF group and 78.75% (63/80) in the PEG-rhG-CSF group ( χ2 = 0.82, P = 0.360). The incidence of related adverse reactions was 7.95% (7/88) and 7.5% (6/80) in the rhG-CSF and PEG-rhG-CSF groups respectively ( χ2 = 0.01, P = 0.910). The average cost was (124.88 ± 113.07) yuan and (3 159.04 ± 505.05) yuan in the rhG-CSF and PEG-rhG-CSF groups respectively ( t = 51.68, P < 0.01). The cost-effectiveness ratio was 1.55 and 40.11 in the rhG-CSF and PEG-rhG-CSF groups respectively. Taking the rhG-CSF group as a reference, the incremental cost-effectiveness ratio in the PEG-rhG-CSF group was 505.13. Conclusion:Long-acting and short-acting recombinant human granulocyte stimulating factors have similar curative effects and related adverse reactions in the treatment of III° and IV°bone marrow suppression after chemotherapy. The cost-effectiveness ratio of the rhG-CSF group is lower than that of the PEG-rhG-CSF group. Appropriate treatment schemes for increasing white blood cell levels should be selected based on the individual situation of the patient.

Progress of Research on Programmed Death-1/Programmed Death Ligand-1 Inhibitors for HIV/AIDS with Cancer / 肿瘤防治研究

Immunotherapy has become a common means of cancer treatment. In immunotherapy, PD-1/PD-L1 inhibitors have significant efficacy. Cancer and various opportunistic infections are common complications in patients with AIDS. Owing to the special immune situation of these patients, AIDS is regarded as an exclusion standard in most clinical trials for cancer immunotherapy, conferring immunotherapy difficulty in treating patients with AIDS. The popularity of effective antiretroviral drugs has prolonged the lifetime of people with AIDS. Therefore, exploiting the opportunity of using immunotherapy in AIDS with cancer is urgent.

Effect of total flavonoids of Rosa rugosa on PI3K/AKT pathway and endoplasmic reticulum stress apoptosis in rats with cerebral ischemia-reperfusion injury / 中国药理学通报

Aim To investigate the effects of total flavonoids from Rosa rugosa (TFR) on cerebral ischemia reperfusion injury (CIRI) in rats, and to investigate whether TFR inhibited neuronal apoptosis by regulating phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) signaling pathway and endoplasmic reticulum stress (ERS) pathways. Methods SD rats were randomly divided into sham operation group, model group, low-dose group (50 mg · kg

Regulation of platelet function by cantharidin via PI3K/Akt/PKC pathway / 中国药理学通报

To investigate the effect of cantharidin ( CTD) on platelet function and the mechanism of anti-platelet aggregation. Methods Washed platelets were collected from the venous blood of healthy volunteers. The effect of CTD on platelet aggregation and release was determined by aggregometer. The CTD concentration was 2.5 ,5 ,10 μmol • L

Whole-brain Optical Imaging: A Powerful Tool for Precise Brain Mapping at the Mesoscopic Level / 神经科学通报·英文版

The mammalian brain is a highly complex network that consists of millions to billions of densely-interconnected neurons. Precise dissection of neural circuits at the mesoscopic level can provide important structural information for understanding the brain. Optical approaches can achieve submicron lateral resolution and achieve "optical sectioning" by a variety of means, which has the natural advantage of allowing the observation of neural circuits at the mesoscopic level. Automated whole-brain optical imaging methods based on tissue clearing or histological sectioning surpass the limitation of optical imaging depth in biological tissues and can provide delicate structural information in a large volume of tissues. Combined with various fluorescent labeling techniques, whole-brain optical imaging methods have shown great potential in the brain-wide quantitative profiling of cells, circuits, and blood vessels. In this review, we summarize the principles and implementations of various whole-brain optical imaging methods and provide some concepts regarding their future development.

Status Quo and Research Progress in Diagnosis and Treatment of Patients With Diabetes Mellitus and Chronic Kidney Disease / 中国医学科学院学报

As the incidence of diabetes mellitus is rapidly increasing worldwide,that of related complications,such as diabetic kidney disease(DKD),also increases,conferring a heavy economic burden on the patients,families,society,and government.Diabetes mellitus complicated with chronic kidney disease(CKD)includes DKD and the CKD caused by other reasons.Because of the insufficient knowledge about CKD,the assessment of diabetes mellitus complicated with CKD remains to be improved.The therapies for diabetes mellitus complicated with CKD focus on reducing the risk factors.In clinical practice,DKD may not be the CKD caused by diabetes.According to clinical criteria,some non-diabetic kidney disease may be misdiagnosed as DKD and not be treated accurately.This review summarizes the status quo and research progress in the assessment,diagnosis,and treatment of diabetes mellitus complicated with CKD and predicts the directions of future research in this field.

Establishment of a Rat Model of Hypotension Induced by Reserpine / 中国医学科学院学报

Objective To determine the optimal dosage and intervention duration of reserpine to establish a rat model of hypotension.Methods According to the body weight and systolic blood pressure (SBP),60 male Wistar rats were assigned to six groups (n=10),including a control group and five observation groups with different doses.The control group was administrated with 10 ml/kg 0.5% sodium carboxymethyl cellulose solution,and the observation groups with 0.016,0.032,0.064,0.128,and 0.160 mg/kg reserpine suspensions,respectively.All the groups were administrated by gavage twice a day,and the body weights of rats were monitored daily.SBP and heart rate (HR) were measured before modeling and 1-6 weeks after administration.After 6 weeks of administration,the blood samples of inner canthus were collected.The levels of lactate dehydrogenase (LDH),creatine kinase MB isoenzyme (CK-MB),alanine aminotransferase,aspartate aminotransferase (AST),serum creatinine,and blood urea nitrogen (BUN) were measured by an autoanalyzer.Three rats in each group were randomly selected for observation of the changes in SBP after drug withdrawal and the rest rats were sacrificed for measurement of the levels of norepinephrine and dopamine in the brain.Results Compared with the control group,different doses of reserpine lowered the SBP of rats (F=28.492,P<0.001).The decline in SBP increased in a concentration-dependent manner.SBP reached the lowest value after 1 week,rose slightly later,and was stable after 3 weeks of administration.There was no significant difference in SBP between 0.016 mg/kg reserpine group and the control group after the 5th week (P>0.05).The SBP levels of rats in 0.032,0.064,0.128,and 0.160 mg/kg reserpine groups showed no significant difference between each other (P=0.204) and were lower than that in the control group (all P<0.001).One week after drug withdrawal,the SBP of rats in the observation groups rose to the baseline level and remained stable.HR showed similar changes among groups,first increasing and then decreasing.There was no significant difference in HR among different groups at the same time point (F=0.922,P=0.475).Compared with the control group,reserpine of different doses reduced the norepinephrine content in the hippocampus (all P<0.001),and 0.128 mg/kg (P=0.045) and 0.160 mg/kg (P=0.042) reserpine lowered the dopamine level in the striatum,which showed no significant differences between different reserpine groups(P=0.343,P=0.301).The levels of LDH,CK-MB,and BUN in the serum increased with the increase in reserpine concentration,and the levels of LDH (P=0.001),CK-MB (P=0.020),AST (P=0.007),and BUN (P=0.001) in the 0.160 mg/kg reserpine group were significantly different from those in the control group.Conclusions The rat model of hypotension can be induced by gavage with reserpine.The gavage with reserpine at a dose of 0.032 mg/kg,twice a day for three consecutive weeks is the optimal scheme for the modeling.After the model establishment,continuous administration is essential to maintain the hypotension.

Analysis of the regular monitoring of occupational hazards in Guangdong Province in 2022 / 中国职业医学

Objective To analyze the overall situation of regular monitoring of occupational hazards in enterprises in Guangdong Province in 2022. Methods Analysis and quality sampling from enterprises were conducted on the occupational hazard regular monitoring reports submitted by various occupational health institutions through the Guangdong Province Occupational Health Quality Control Platform for the year 2022. Results In 2022, a total of 40 129 enterprises in Guangdong Province conducted regular monitoring of occupational hazards, accounting for 5.9%. More than 4.85 million workers were enrolled, of which more than 1.99 million workers were exposed to occupational hazards, with an incidence of 41.1%. The incidence of exposure to chemicals, dust, and noise were 18.2%, 11.9%, and 23.5%, respectively. The incidence of exceeding national standard for chemical substances, dust and noise in enterprises were 2.7%, 3.3%, and 42.7%, respectively. The incidence of exceeding national standard for all occupational hazards increased with the scale of enterprises from micro, small, medium to large enterprises (29.1% vs 46.7% vs 61.3% vs 65.4%, all P<0.05). The top three key industries, with more enterprises exceeding national standard, were metal furniture manufacturing, wooden furniture manufacturing, and other metal daily necessities manufacturing. The concentration of 97 chemical hazardous agents such as silica dust and benzene in work site exceeded the national standard, but less than 1.0% chemical hazardous agents exceeded national standard in most of the chemical-exposed work site. The incidence of noise exceeding national standard was 45.4%, while the incidence of silica dust exceeding national standard was 17.3%. Conclusion The percentage of regular monitoring of occupational hazards in enterprises in Guangdong Province is relatively low. The main occupational hazard that exceeds the national standard was noise, indicating the need for special attention on noise protection in workplace.