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1.
Chem Asian J ; : e202400892, 2024 Aug 27.
Article in English | MEDLINE | ID: mdl-39189789

ABSTRACT

Transition metal-catalyzed carbonylation functionalization reaction of alkenes is an attractive research area in modern organic chemistry. However, there have been very few reports on silver-catalyzed reactions in carbonylation reactions. Herein we developed a silver-catalyzed carbamoylation and carbonylative cyclization of alkenes with oxamic acids to obtain 2-acetylamino-1-tetralone derivatives. Various desired cyclized products were formed in moderate to good yields through radical intermediates.

2.
J Phys Chem Lett ; 15(34): 8613-8619, 2024 Aug 29.
Article in English | MEDLINE | ID: mdl-39146260

ABSTRACT

Scanning tunneling microscopy (STM) serves as a critical tool for high-resolution surface imaging, yet deciphering the atomic structures from STM images on multielement surfaces, such as oxides and carbides, remains a challenging task that heavily relies on the expertise and intuition of researchers. In this study, we introduce a data-driven method for rapid structural recognition from STM images. This method involves extracting structural features, filtering through a structural database, and matching with simulated STM images and surface energy analyses, thereby providing researchers with several of the most probable structures. We demonstrate the capabilities of this technique using our previously reported iron carbide grown on an Fe(110) crystal. By proposing a candidate structure set and establishing a comprehensive database linking STM images to corresponding structures and surface energies, we selected 6 out of more than 10 000 possible surfaces. On the basis of these 6 recommendations, researchers can conveniently determine the real surface structures. Our work provides an efficient tool for the structure recognition of STM images to construct surface structures, potentially serving as a universal auxiliary tool for STM structural analysis.

3.
Nat Commun ; 15(1): 5128, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38879628

ABSTRACT

Accurately controlling the product selectivity in syngas conversion, especially increasing the olefin selectivity while minimizing C1 byproducts, remains a significant challenge. Epsilon Fe2C is deemed a promising candidate catalyst due to its inherently low CO2 selectivity, but its use is hindered by its poor high-temperature stability. Herein, we report the successful synthesis of highly stable ε-Fe2C through a N-induced strategy utilizing pyrolysis of Prussian blue analogs (PBAs). This catalyst, with precisely controlled Mn promoter, not only achieved an olefin selectivity of up to 70.2% but also minimized the selectivity of C1 byproducts to 19.0%, including 11.9% CO2 and 7.1% CH4. The superior performance of our ε-Fe2C-xMn catalysts, particularly in minimizing CO2 formation, is largely attributed to the interface of dispersed MnO cluster and ε-Fe2C, which crucially limits CO to CO2 conversion. Here, we enhance the carbon efficiency and economic viability of the olefin production process while maintaining high catalytic activity.

4.
J Phys Chem Lett ; 15(16): 4384-4390, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38659407

ABSTRACT

Rational design of catalysts relies on a deep understanding of the active centers. The structure and activity distribution of active centers on a surface are two of the central issues in catalysis and important targets of theoretical and experimental investigations. Herein, we report a machine learning-driven adequate sampling (MLAS) framework for obtaining a statistical understanding of the chemical environment near catalyst sites. Combined strategies were implemented to achieve highly efficient sampling, including the decomposition of degrees of freedom, stratified sampling, Gaussian process regression, and well-designed constraint optimization. The MLAS framework was applied to the rate-determining step in NH3 synthesis, namely the N2 activation process. We calculated the produced population function, PA, which provides a comprehensive and intuitive understanding of active centers. The MLAS framework can be broadly applied to other more complicated catalyst materials and reaction networks.

5.
Opt Lett ; 49(6): 1437-1440, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38489419

ABSTRACT

A high-performance 5-junction cascade quantum dot (QD) vertical cavity surface-emitting laser (VCSEL) with 1.3 µm wavelength was designed. The characteristics of the QD as active regions and tunnel junctions are combined to effectively increase output power. The photoelectric characteristics of single-junction, 3-junction cascade, and 5-junction cascade QD VCSELs are compared at continuous-wave conditions. Results indicate that the threshold current gradually decreases, and the output power and slope efficiency exponential increase with the increase of the number of active regions. The peak power conversion efficiency of 58.4% is achieved for the 5-junction cascade individual QD VCSEL emitter with 10 µm oxide aperture. The maximum slope efficiency of the device is 6.27 W/A, which is approximately six times than that of the single-junction QD VCSEL. The output power of the 5-junction cascade QD VCSEL reaches 188.13 mW at injection current 30 mA. High-performance multi-junction cascade 1.3-µm QD VCSEL provides data and theoretical support for the preparation of epitaxial materials.

6.
Org Biomol Chem ; 22(13): 2630-2642, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38456330

ABSTRACT

Non-noble metal-based catalyst systems consisting of inexpensive manganese salts, picolinic acid and various heterocycles enable epoxidation of the challenging (terminal) unactivated olefins, selective C-H oxidation of unactivated alkanes, and O-H oxidation of secondary alcohols with aqueous hydrogen peroxide. In the presence of the in situ generated optimal manganese catalyst, epoxides are generated with up to 81% yield from alkenes and ketone products with up to 51% yield from unactivated alkanes. This convenient protocol allows the formation of the desired products under ambient conditions (room temperature, 1 bar) by employing only a slight excess of hydrogen peroxide with 2,3-butadione as a sub-stoichiometric additive.

7.
J Asian Nat Prod Res ; 26(3): 342-352, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37933140

ABSTRACT

Bicyclol, an innovative hepatoprotective drug, was approved by the Chinese National Medical Products Administration (NMPA) in 2001 to treat Hepatitis B and drug-induced liver injury. Two active metabolites of bicyclol have been identified as M2 and M3. To evaluate the impact on drug safety and efficacy of possible drug-drug interactions (DDIs) associated with these metabolites, a sufficient quantity of these metabolites is required. Herein, we report a concise novel route for the synthesis of M2 and M3 using the Suzuki-Miyaura coupling as the key step. Furthermore, we complete the gram-scale syntheses of M2 and M3.


Subject(s)
Biphenyl Compounds , Chemical and Drug Induced Liver Injury , Biphenyl Compounds/pharmacology , Protective Agents , Chemical and Drug Induced Liver Injury/drug therapy
8.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1005897

ABSTRACT

Objective To explore the research progress, research hotspot and development trend of tigecycline resistance based on the quantitative analysis and visualization function of CiteSpace. Methods The data were collected from 4,263 Chinese and English articles on tigecycline resistance in CNKI, Wanfang, VIP and Web of Science (WOS) databases from 2012 to 2022. CiteSpace 5.8.R3 software was used to analyze the cooperative network of authors, the cooperative network of countries and institutions, the total citation times of journals, and keywords included in the literature, to reveal the hotspots and trends of tigecycline resistance research. Results The number of articles published in English literature was higher than that in Chinese literature. China had the largest number of published documents, showing a significant international academic influence in this research field. Countries all over the world were concerned about the resistance of tigecycline, but Chinese literatures focused more on the clinical infection and prevention of tigecycline resistance, while English literatures placed special emphasis on the research about the drug resistance mechanism of tigecycline. Conclusion The research direction at home and abroad is basically the same, but the research focus has gradually shifted from the clinical treatment and monitoring of tigecycline to the molecular level of drug resistance mechanism.

9.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1016984

ABSTRACT

Objective In this study, a strain of colistin and tigecycline-resistant bacteria isolated in 2009 was analyzed, and the structure of drug-resistant plasmid and genetic environment were discussed, so as to provide basis for the prevention and control of multidrug-resistant bacteria. Methods A strain (GZ12244) with positive mcr and tet(M) was obtained by screening colistin and tigecycline resistance genes. Vitek-2 was used for strain identification, and the drug sensitivity test was carried out by broth dilution method. The molecular typing, drug resistance genes, insertion sequences, plasmid structure and genetic background were analyzed by genome-wide sequencing and bioinformatics. Results Strain GZ12244 is Klebsiella pneumoniae, which is resistant to colistin B, tigecycline, cefuroxime and tetracycline, and carries a variety of drug-resistant related genes such as mcr-1 and tet(M), and some of the drug-resistant genes with antibiotic efflux and antibiotic target change have amino acid substitution mutations. Mcr-1 and tet(M) coexist in a plasmid, and mcr-1 flanked by two insertion sequences ISApl1. There are insertion sequences such as IS15, IS1D and ISEc63 in the upstream and downstream of tet(M) gene. Conclusion Klebsiella pneumoniae GZ12244 is a multidrug-resistant strain. The drug-resistant gene exists in plasmid, and the mobile elements in upstream and downstream may spread the drug-resistant gene.

10.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1017271

ABSTRACT

Objective:To develop an efficient and robust method based on three dimensional facial landmarks for evaluating chin region asymmetry at the soft tissue level and to compare it with the tradi-tional mirror-overlap analysis method in order to test its availability.Methods:Standard symmetrical face was used for mental tubercle coordinate transformation so as to filter soft tissue three dimensional spatial angle and construct corresponding three dimensional spatial angle wireframe template.Ten patients aged 12-32 years with clinical chin region asymmetry diagnosis at the Department of Orthodontics of Peking University Hospital of Stomatology from November 2020 to November 2021 were randomly selected.Three dimensional soft tissue face scan data of the patients were collected by three dimensional face scanner and the landmark points were automatically determined by the Meshmonk non-rigid registration algorithm pro-gram,and in this way,the asymmetric three dimensional spatial angle wireframe template and corre-sponding spatial angle parameters were generated.Mirror-overlap analysis of face scan data was also per-formed in Geomagic Studio 2015 software and deviation color maps were generated.This study took mirror-overlap analysis as the gold standard method,the response rate of chin region asymmetry was eva-luated by the outcomes of the mirror-overlap analysis and three dimensional spatial angle wireframe tem-plate analysis.Results:Nine three dimensional spatial angle indicators were selected through coordinate transformation,and the response rate was calculated using mirror-overlap analysis as the gold standard method.Among these ten selected patients,the response rate of the total chin region asymmetry was 90%(9/10).Using the deviation value of mirror-overlap analysis as a reference,the response rate of chin region asymmetry in the X dimension was 86%,the response rate of chin region asymmetry in the Y dimension was 89%,and the response rate of chin region asymmetry in the Z dimension was 100%.Conclusion:The three dimensional soft tissue spatial angle wireframe template proposed in this study has some feasibility in evaluating chin region asymmetry at the soft tissue level,and its ability to recognize asymmetry separately in the three dimensional direction is better than the mirror-overlap analysis method,and the indicators recognition rate still needs to be further improved.

11.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1017861

ABSTRACT

Objective To analyze the correlation between serum miR-939 and miR-15b expression and mi-crovascular injury in patients with diabetic retinopathy(DR).Methods A total of 176 patients with type 2 di-abetes diagnosed and treated in the Baoding Second Hospital from January 2021 to October 2022 were selected as the study objects.The subjects were divided into 74 patients without DR(NDR group),62 patients with non-proliferative DR(NPDR group)and 40 patients with proliferative DR(PDR group)according to whether or not DR occurred and the degree of lesions.Real-time fluorescent quantitative PCR was used to detect the relative expression levels of miR-939 and miR-15b in serum of all groups,the level of vascular endothelial growth factor(VEGF)was detected by enzyme-linked immunosorbent assay,and the count percentage of en-dothelial cells(ECs),endothelial progenitor cells(EPCs)and circulating progenitor cells(CPCs)was detected by flow cytometry.Serum levels of miR-939,miR-15b,VEGF and ECs,EPCs and CPCs were compared in 3 groups.Pearson correlation was used to analyze the correlation between serum miR-939 and miR-15b and VEGF,ECs,EPCs and CPCs.Multivariate Logistic regression was used to analyze the factors affecting the oc-currence of DR in patients with type 2 diabetes.Results The relative expression levels of miR-939 and miR-15b in PDR group and NPDR group were lower than those in NDR group,while the serum VEGF levels were higher than those in NDR group,with statistical significance(P<0.05).ECs in PDR group and NPDR group were higher than those in NDR group,while EPCs and CPCs were lower than those in NDR group,the differ-ence was statistically significant(P<0.05).Serum miR-939 was negatively correlated with VEGF and ECs(r=-0.407,-0.613,P<0.05),and positively correlated with EPCs and CPCs(r=0.481,0.486,P<0.05).Serum miR-15b was negatively correlated with VEGF and ECs(r=-0.539,-0.625,P<0.05),and positively correlated with EPCs and CPCs(r=0.451,0.483,P<0.05).Multivariate Logistic regression anal-ysis showed that the duration of type 2 diabetes,hemoglobin A1c,2-hour postprandial blood glucose,VEGF,miR-939 and miR-15b were the influencing factors for the occurrence of DR in type 2 diabetes patients(P<0.05).Conclusion The expression of miR-939 and miR-15b in serum of DR patients is closely related to VEGF,ECs,EPCs and CPCs,and the expression of miR-939 and miR-15b in serum of DR patients can provide a certain reference for early judgment and evaluation of the degree of microvascular injury.

12.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1017887

ABSTRACT

Objective To investigate the value of peripheral blood soluble interleukin-2 receptor(sIL-2R),CD4+lymphocyte percentage/CD8+lymphocyte percentage ratio(hereinafter referred to as CD4+/CD8+)and tumor necrosis factor-α(TNF-α)in evaluating the efficacy of chemotherapy in elderly patients with newly treated active pulmonary tuberculosis.Methods A total of 102 elderly patients with newly treated active tu-berculosis admitted to the hospital from December 2019 to December 2022 were enrolled in the study as the observation group,and 102 healthy people aged 60 and older who underwent physical examination in the hos-pital during the same period were enrolled as the control group.The levels of sIL-2R,TNF-α and CD4+/CD8+in peripheral blood were compared between the two groups,and the correlations between sIL-2R,TNF-α and CD4+/CD8+were analyzed.The observation group was treated with 2HRZE/4HR anti-tuberculosis treatment regimen.The levels of sIL-2R,TNF-α and CD4+/CD8+in peripheral blood of patients with different efficacy before treatment,1 month and 6 months after treatment in the observation group were compared.The correla-tion between sIL-2R,CD4+/CD8+,TNF-α levels and therapeutic effect was analyzed.The receiver operating characteristic(ROC)curve was used to analyze the efficacy of indicators in evaluating the efficacy of chemo-therapy in elderly patients.Results The levels of sIL-2R and TNF-α in the observation group were higher than those in the control group,while CD4+/CD8+was lower than that in the control group,and the differ-ences were statistically significant(P<0.05).In the observation group,sIL-2R and TNF-α were negatively correlated with CD4+/CD8+(P<0.05),sIL-2R was positively correlated with TNF-α(P<0.05).After 1 month and 6 months of treatment,the levels of sIL-2R and TNF-α in patients with apparent efficacy were low-er than those in patients with efficacy,and the latter were lower than those in patients with no effect,while the CD4+/CD8+in patients with apparent efficacy was higher than that in patients with efficacy,and the latter was higher than that in patients with no efficacy,and the differences were statistically significant(P<0.05).The levels of sIL-2R and TNF-α were negatively correlated with the efficacy(P<0.05),and CD4+/CD8+was positively correlated with the efficacy(P<0.05).ROC curve analysis showed that the area under the curve(AUC)of sIL-2R,CD4+/CD8+,and TNF-α used in combination to assess efficacy was significantly greater than the AUCs of the single indicators used in the assessment at each time point of treatment(P<0.05),and the AUC of the combination of the indicators was greater after 6 months of treatment than after 1 month of treatment(P<0.05).Conclusion The levels of sIL-2R,CD4+/CD8+and TNF-α are closely related to the ef-ficacy of chemotherapy in elderly patients with newly treated active pulmonary tuberculosis,and the combina-tion of the above indicators has certain reference value in evaluating the efficacy of chemotherapy in patients.

13.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1019604

ABSTRACT

Objective To study the effect of drinking carbohydrate drinks before cesarean section on mothers and neonates,and to explore the application value of drinking carbohydrate drinks before cesarean section.Methods The clinical data of 206 singleton women who underwent selective cesarean section in Obstetrics and Gynecology Hospital,Fudan University from Jun 2020 to Jun 2021 were retrospectively studied.Patients were divided into enhanced recovery after delivery(ERAD)group and control group according to whether drinking carbohydrate drinks before cesarean section.A retrospective cohort study was conducted to analyze the effect of preoperative carb drinks on preoperative fluid supplementation,postoperative rehabilitation and neonatal prognosis.Results Among patients who fasted for less than 12 hours,the ERAD group had a lower fluid supplementation rate and a smaller average fluid supplementation volume compared to the control group(P<0.05).The ERAD group had a lower rate of prokinetic agent using after surgery(P<0.05).Among women without a history of abdominal surgery,the ERAD group had less blood loss 24 hours after surgery(P<0.05).There were no significant differences in postoperative fever rate,incidence of nausea and vomiting,time of first flatus,neonatal apgar score,exit observation room neonatal blood,and neonatal neonatal intensive care unit(NICU)admission rate between the two groups.Among newborns with high-risk factors for hypoglycemia,the ERAD group had lower enter observation room neonatal blood compared to the control group,and a higher incidence of hypoglycemia(P<0.05).Conclusion Oral intake of carbohydrate drinks before cesarean section may be beneficial in reducing fluid supplementation before elective cesarean section,promoting postoperative gastrointestinal function recovery,and reducing postoperative bleeding.However,it may be related to the occurrence of neonatal hypoglycemia.

14.
Chinese Journal of Endemiology ; (12): 212-218, 2024.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1024012

ABSTRACT

Objective:To investigate the current situation and related factors of children's growth and development in drinking-water-borne endemic fluorosis areas after water improvement, and provide a basis for improving the control strategies.Methods:The stratified random sampling method was used to select children aged 7 to 13 in villages with different years of water improvement in Xi'an from November 2019 to June 2020. The height and weight of children were measured, and body mass index (BMI) was calculated. The height development level of children was graded according to the "Standard for Height Level Classification among Children and Adolescents Aged 7 - 18 Years" (WS/T 612-2018), and the physical development (BMI) level of children was determined according to the "Comprehensive Evaluation of Development Level for Children and Adolescents" (GB/T 31178-2014). At the same time, according to the standard of "Diagnosis of Dental Fluorosis" (WS/T 208-2011), the diagnosis of dental fluorosis in children was performed. The serum fluoride level was determined by ion selective electrode method, and the levels of other chemical elements (calcium, iron, magnesium, copper, zinc, iodine, selenium, lead, arsenic, cadmium, chromium, mercury, nickel) in blood were determined by inductively coupled plasma mass spectrometry.Results:A total of 469 children were included in the investigation. After water improvement, 67.38% (316/469) of the children in the disease area were at the moderate level of height development, 7.89% (37/469) were at the medium to upper and upper levels, and 24.73% (116/469) were at the medium to lower and lower levels. The BMI of the children in the emaciation group was 8.53% (40/469), while it was 10.87% (51/469) in the overweight group and 8.74% (41/469) in the obesity group. There was statistically significant difference in the distribution of height development level of children in areas with different water improvement years ( P = 0.005), but no statistically significant difference in BMI distribution ( P = 0.154). There was no significant difference in height development level and BMI distribution of children with or without dental fluorosis ( P > 0.05). There were significant differences in serum levels of iron and zinc among children with different height development levels ( P < 0.05). There were significant differences in serum levels of magnesium, copper, iodine and chromium among children with different BMI ( P < 0.05). Conclusion:The growth and development of children in drinking-water-borne endemic fluorosis area after water improvement are not correlated with the prevalence of dental fluorosis, but may be related to the levels of chemical elements such as iron, magnesium, copper, and iodine in the body.

15.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1027994

ABSTRACT

Objective:To analyze the association between visceral fat area (VFA) and fatty liver based on quantitative CT (QCT) in people receiving health examination with normal body mass index (BMI).Methods:A cross-sectional study. A total of 1 305 physical examiners who underwent chest CT and QCT examination in the Department of Health Management of Henan Provincial People′s Hospital from January to December 2021 were retrospectively selected as subjects. The physical components at the central level of the lumbar two cone were measured with QCT, including subcutaneous fat area (SFA), VFA and liver fat content (LFC). And the metabolic indexes, such as blood lipids and blood glucose, were collected. The t-test and χ2 test were used to analyze the correlation between the detection rate of fatty live and LFCr and age and gender. According to level of VFA (<100 cm 2, 100-150 cm 2 and≥150 cm 2), the subjects were divided into three groups, and one-way ANOVA and χ2 test were used in comparison between groups. Multiple linear regression was used to analyze the correlation between VFA and metabolic indexes and LFC. Results:Of the 1 305 subjects, there were 634 males and 671 females. The detection rate of fatty liver in normal BMI population was 65.67%, and it was 72.71% and 59.02% respectively in men and women ( χ2=27.12, P<0.001), and the detection rate of fatty liver and LFC increased with age (both P<0.05). With the increase of VFA, the age, BMI, SFA, LFC, total cholesterol (TC), triacylglycerol (TG), low-density lipoprotein cholesterol (LDL-C), fasting blood glucose (FBG), alanine aminotransferase (ALT), blood uric acid and prevalence of fatty liver increased (all P<0.05), and the low-density lipoprotein cholesterol (HDL-C) decreased ( P<0.001). Multiple linear regression analysis showed that after adjustment for age factors, regardless of male or female, LFC was independently positively related with VFA, BMI, and ALT (male β=0.206, 0.145, 0.174, female β=0.194, 0.150, 0.184; all P<0.05). FBG was positively correlated with male independently ( β=0.134; P<0.001). The indicators related to female independently were TC, TG, and blood uric acid ( β=-0.121, 0.145, 0.141, all P<0.05) Conclusion:In the population receiving health examination with normal BMI, the VFA measured by QCT technique is closely related to fatty liver.

16.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1028729

ABSTRACT

AIM To optimize the processing technology of red Notoginseng Radix et Rhizoma and evaluate its blood tonifying activity.METHODS On the basis of a single factor experiment,with steaming temperature,steaming time,drying temperature,and drying time as influencing factors,the total contents of notoginsenoside R1,ginsenoside Rg1,Rb1,Rk3,Rh4,and 20(R)-ginsenoside Rg3 as evaluation indicators,Box-Behnken response surface method ology was used to optimize the processing technology.Upon the anemic mouse models jointly induced by 1-acetyl-2-phenylhydrazine(APH)and cyclophosphamide(CTX),the investigation of the blood tonifying activity of red Notoginseng Radix et Rhizoma was carried out in contrast to that of the steamed Notoginseng Radix et Rhizoma.RESULTS The optimal conditions,contributing saponin content of 8.326%and RSD of 0.087%,were determined as follows:steaming temperature of 130℃,steaming time of 4 hours,drying temperature of 60℃,and drying time of 48 h.The pharmacological activity revealed that the different processing techniques were responsible for the different blood enriching activity of notoginseng,with red Notoginseng Radix et Rhizoma displaying a better efficacy than that of steamed Notoginseng Radix et Rhizoma.CONCLUSION This stable and feasible method can be used to control the production of red Notoginseng Radix et Rhizoma.

17.
Journal of Modern Urology ; (12): 1-4, 2024.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1031560

ABSTRACT

Retzius-sparing robot assisted radical prostatectomy (RS-RARP) can significantly improve the immediate urinary continence without increasing the positive rate of surgical margin.However, the learning curve is long, and fewer than 10% of the surgeons can master it.Therefore,we have optimized the procedures of RS-RARP, applying radical prostatectomy with retrograde release of neurovascular bundle to preserve it to the maximum extent.Urethral anastomosis can be performed with only one suture, which eliminates the need for Hem-o-lok and reduces subsequent complications.Our team routinely carries out this operation, and conlcudes that this surgical method can achieve good tumor control, good urinary continence, fast recovery of sexual function, few complications, and strong operability.This article details the key steps and operation experience of this technique.

18.
Acta Anatomica Sinica ; (6): 105-112, 2024.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1015145

ABSTRACT

Objective To study the microscopic structure and morphological characteristics of Zebrafish eyeball and retina at different developmental stages, and to lay a foundation for visual research model. Methods Select eight groups of zebrafish at different ages, with six fish in each group, 48 fish in total. Optical microscopy and transmission electron microscopy were used to observe the eyeball structure of Zebrafish at different developmental stages, and the thickness of retinal each layer was measured to analyze the temporal and spatial development pattern. The morphological characteristics of various cells in the retina and the way of nerve connection were observed from the microscopic and ultrastructural aspects, especially the structural differences between rod cells and cone cells. Results The retina of Zebrafish can be divided into ten layers including retinal pigment epithelial layer, rod cells and cone cells layer, outer limiting membrane, outer nuclear layer, outer plexiform layer, inner nuclear layer, inner plexiform layer, ganglion cell layer, nerve fiber layer, inner limiting membrane. Rod cells had a smaller nucleus and a higher electron density than cone cells. Photoreceptor terminals were neatly arranged in the outer plexiform layer, forming neural connections with horizontal cells and bipolar cells, and several synaptic ribbons are clearly visible within them. In Zebrafish retina, ganglion cell layer and inner plexiform layer are the earliest developed. With the growth and development of Zebrafish, the thickness of rod cells and cone cells layer and retinal pigment epithelial layer gradually increases, and the retinal structure was basically developed in about 10 weeks. Conclusion The retinal structure of Zebrafish is typical, with obvious stratification and highly differentiated nerve cells. There are abundant neural connections in the outer plexiform layer. The ocular development characteristics of Zebrafish are similar to those of most mammals.

19.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1016401

ABSTRACT

Objective To analyze the research status and trend of scarlet fever literature in China, and to provide reference for subsequent research. Methods Three major Chinese databases, CNKI, Wanfang, and VIP, as well as Web of Science English database, were used to search for literature related to scarlet fever from 2000 to 2023. Citespace6.2.R2 software was used to statistically analyze the number of publications, authors, institutions and journals, co-cited literature, keyword clustering, and other literature characteristics of the literature. Results From 2000 to 2023, a total of 1 011 Chinese literature were included in the three major Chinese databases. Since 2011, the number of publications had gradually increased, but in recent years, the number of publications had decreased. The organization with the most publications was the Shenyang Center for Disease Control and Prevention. The cluster analysis of key words mainly formed 9 cluster tags, and the high-frequency keywords mainly included epidemic characteristics, epidemiology, incidence rate, etc. A total of 84 English literature were included in the WOS database, with an overall upward trend in publication volume. The institution with the most publications was the China Center for Disease Control and Prevention, and the most frequently cited journal was “LANCET INFECT DIS”.《Resurgence of scarlet fever in China: a 13-year population-based surveillance study》 was the most cited journal. After keyword cluster analysis, 9 cluster labels were mainly formed, and the keywords were mainly outbreak,Hong Kong, and Group A streptococcus. Conclusion Compared with the English literature, which mainly focuses on spatiotemporal aggregation, etiology and strain resistance, Chinese literature focuses more on epidemic surveillance, clinical features and quality nursing.

20.
Article in English | WPRIM (Western Pacific) | ID: wpr-1011012

ABSTRACT

Pathological vascular remodeling is a hallmark of various vascular diseases. Previous research has established the significance of andrographolide in maintaining gastric vascular homeostasis and its pivotal role in modulating endothelial barrier dysfunction, which leads to pathological vascular remodeling. Potassium dehydroandrographolide succinate (PDA), a derivative of andrographolide, has been clinically utilized in the treatment of inflammatory diseases precipitated by viral infections. This study investigates the potential of PDA in regulating pathological vascular remodeling. The effect of PDA on vascular remodeling was assessed through the complete ligation of the carotid artery in C57BL/6 mice. Experimental approaches, including rat aortic primary smooth muscle cell culture, flow cytometry, bromodeoxyuridine (BrdU) incorporation assay, Boyden chamber cell migration assay, spheroid sprouting assay, and Matrigel-based tube formation assay, were employed to evaluate the influence of PDA on the proliferation and motility of smooth muscle cells (SMCs). Molecular docking simulations and co-immunoprecipitation assays were conducted to examine protein interactions. The results revealed that PDA exacerbates vascular injury-induced pathological remodeling, as evidenced by enhanced neointima formation. PDA treatment significantly increased the proliferation and migration of SMCs. Further mechanistic studies disclosed that PDA upregulated myeloid differentiation factor 88 (MyD88) expression in SMCs and interacted with T-cadherin (CDH13). This interaction augmented proliferation, migration, and extracellular matrix deposition, culminating in pathological vascular remodeling. Our findings underscore the critical role of PDA in the regulation of pathological vascular remodeling, mediated through the MyD88/CDH13 signaling pathway.


Subject(s)
Mice , Rats , Animals , Myeloid Differentiation Factor 88/metabolism , Vascular Remodeling , Cell Proliferation , Vascular System Injuries/pathology , Carotid Artery Injuries/pathology , Molecular Docking Simulation , Muscle, Smooth, Vascular , Cell Movement , Mice, Inbred C57BL , Signal Transduction , Succinates/pharmacology , Potassium/pharmacology , Cells, Cultured , Diterpenes , Cadherins
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