1.Expert consensus on implementation strategy of awake prone positioning for non-intubated patients in China (2023).
Yuanyuan MI ; Zheyi CAI ; Jing LIU ; Fei TIAN ; Liping YANG ; Lei BAO ; Shanbing HOU ; Su GU ; Li LI ; Xueli ZHOU ; Yun XU ; Shumei ZHANG ; Xiaoxia FU ; Xiaodi LI ; Chuansheng LI ; Liang SUN ; Xiaohong ZHANG ; Hong QI ; Shiying YUAN ; Liqun ZHU ; Haiyan HUANG ; You SHANG
Chinese Critical Care Medicine 2023;35(4):337-351
		                        		
		                        			
		                        			The awake prone position plays an important role in the treatment of hypoxemia and the improvement of respiratory distress symptoms in non-intubated patients. It is widely used in clinical practice because of its simple operation, safety, and economy. To enable clinical medical staff to scientifically and normatively implement prone position for awake patients without intubation, the committees of consensus formulation, guided by evidence-based methodology and Delphi method, conducted literature search, literature quality evaluation and evidence synthesis around seven topics, including indications and contraindications, evaluation, implementation, monitoring and safety management, termination time, complication prevention and health education of awake prone position. After two rounds of expert letter consultation, Expert consensus on implementation strategy of awake prone positioning for non-intubated patients in China (2023) was formulated, and provide guidance for clinical medical staff.
		                        		
		                        		
		                        		
		                        			Humans
		                        			;
		                        		
		                        			Consensus
		                        			;
		                        		
		                        			Prone Position
		                        			;
		                        		
		                        			Wakefulness
		                        			;
		                        		
		                        			China
		                        			;
		                        		
		                        			Dyspnea
		                        			
		                        		
		                        	
2.Current status of diagnosis and treatment of chronic lymphocytic leukemia in China: A national multicenter survey research.
Wei XU ; Shu Hua YI ; Ru FENG ; Xin WANG ; Jie JIN ; Jian Qing MI ; Kai Yang DING ; Wei YANG ; Ting NIU ; Shao Yuan WANG ; Ke Shu ZHOU ; Hong Ling PENG ; Liang HUANG ; Li Hong LIU ; Jun MA ; Jun LUO ; Li Ping SU ; Ou BAI ; Lin LIU ; Fei LI ; Peng Cheng HE ; Yun ZENG ; Da GAO ; Ming JIANG ; Ji Shi WANG ; Hong Xia YAO ; Lu Gui QIU ; Jian Yong LI
Chinese Journal of Hematology 2023;44(5):380-387
		                        		
		                        			
		                        			Objective: To understand the current status of diagnosis and treatment of chronic lymphocytic leukemia (CLL) /small lymphocytic lymphoma (SLL) among hematologists, oncologists, and lymphoma physicians from hospitals of different levels in China. Methods: This multicenter questionnaire survey was conducted from March 2021 to July 2021 and included 1,000 eligible physicians. A combination of face-to-face interviews and online questionnaire surveys was used. A standardized questionnaire regarding the composition of patients treated for CLL/SLL, disease diagnosis and prognosis evaluation, concomitant diseases, organ function evaluation, treatment selection, and Bruton tyrosine kinase (BTK) inhibitor was used. Results: ①The interviewed physicians stated that the proportion of male patients treated for CLL/SLL is higher than that of females, and the age is mainly concentrated in 61-70 years old. ②Most of the interviewed physicians conducted tests, such as bone marrow biopsies and immunohistochemistry, for patient diagnosis, in addition to the blood test. ③Only 13.7% of the interviewed physicians fully grasped the initial treatment indications recommended by the existing guidelines. ④In terms of cognition of high-risk prognostic factors, physicians' knowledge of unmutated immunoglobulin heavy-chain variable and 11q- is far inferior to that of TP53 mutation and complex karyotype, which are two high-risk prognostic factors, and only 17.1% of the interviewed physicians fully mastered CLL International Prognostic Index scoring system. ⑤Among the first-line treatment strategy, BTK inhibitors are used for different types of patients, and physicians have formed a certain understanding that BTK inhibitors should be preferentially used in patients with high-risk factors and elderly patients, but the actual use of BTK inhibitors in different types of patients is not high (31.6%-46.0%). ⑥BTK inhibitors at a reduced dose in actual clinical treatment were used by 69.0% of the physicians, and 66.8% of the physicians had interrupted the BTK inhibitor for >12 days in actual clinical treatment. The use of BTK inhibitors is reduced or interrupted mainly because of adverse reactions, such as atrial fibrillation, severe bone marrow suppression, hemorrhage, and pulmonary infection, as well as patients' payment capacity and effective disease progression control. ⑦Some differences were found in the perceptions and behaviors of hematologists and oncologists regarding the prognostic assessment of CLL/SLL, the choice of treatment options, the clinical use of BTK inhibitors, etc. Conclusion: At present, a gap remains between the diagnosis and treatment of CLL/SLL among Chinese physicians compared with the recommendations in the guidelines regarding the diagnostic criteria, treatment indications, prognosis assessment, accompanying disease assessment, treatment strategy selection, and rational BTK inhibitor use, especially the proportion of dose reduction or BTK inhibitor discontinuation due to high adverse events.
		                        		
		                        		
		                        		
		                        			Female
		                        			;
		                        		
		                        			Humans
		                        			;
		                        		
		                        			Male
		                        			;
		                        		
		                        			Aged
		                        			;
		                        		
		                        			Middle Aged
		                        			;
		                        		
		                        			Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy*
		                        			;
		                        		
		                        			Prognosis
		                        			;
		                        		
		                        			Lymphoma, B-Cell
		                        			;
		                        		
		                        			Immunohistochemistry
		                        			;
		                        		
		                        			Immunoglobulin Heavy Chains/therapeutic use*
		                        			
		                        		
		                        	
3.Analysis of clinicopathological and molecular abnormalities of angioimmunoblastic T-cell lymphoma.
Yun Fei SHI ; Hao Jie WANG ; Wei Ping LIU ; Lan MI ; Meng Ping LONG ; Yan Fei LIU ; Yu Mei LAI ; Li Xin ZHOU ; Xin Ting DIAO ; Xiang Hong LI
Journal of Peking University(Health Sciences) 2023;55(3):521-529
		                        		
		                        			OBJECTIVE:
		                        			To analyze the clinicopathological features, molecular changes and prognostic factors in angioimmunoblastic T-cell lymphoma (AITL).
		                        		
		                        			METHODS:
		                        			Sixty-one cases AITL diagnosed by Department of Pathology of Peking University Cancer Hospital were collected with their clinical data. Morphologically, they were classified as typeⅠ[lymphoid tissue reactive hyperplasia (LRH) like]; typeⅡ[marginal zone lymphoma(MZL)like] and type Ⅲ [peripheral T-cell lymphoma, not specified (PTCL-NOS) like]. Immunohistochemical staining was used to evaluate the presence of follicular helper T-cell (TFH) phenotype, proliferation of extra germinal center (GC) follicular dendritic cells (FDCs), presence of Hodgkin and Reed-Sternberg (HRS)-like cells and large B transformation. The density of Epstein-Barr virus (EBV) + cells was counted with slides stained by Epstein-Barr virus encoded RNA (EBER) in situ hybridization on high power field (HPF). T-cell receptor / immunoglobulin gene (TCR/IG) clonality and targeted exome sequencing (TES) test were performed when necessary. SPSS 22.0 software was used for statistical analysis.
		                        		
		                        			RESULTS:
		                        			Morphological subtype (%): 11.4% (7/61) cases were classified as type Ⅰ; 50.8% (31/61) as type Ⅱ; 37.8% (23/61) as type Ⅲ. 83.6% (51/61) cases showed classical TFH immunophenotype. With variable extra-GC FDC meshwork proliferation (median 20.0%); 23.0% (14/61) had HRS-like cells; 11.5% (7/61) with large B transformation. 42.6% (26/61) of cases with high counts of EBV. 57.9% (11/19) TCR+/IG-, 26.3% (5/19) TCR+/IG+, 10.5% (2/19) were TCR-/IG-, and 5.3% (1/19) TCR-/IG+. Mutation frequencies by TES were 66.7% (20/30) for RHOA, 23.3% (7/30) for IDH2 mutation, 80.0% (24/30) for TET2 mutation, and 33.3% (10/30) DNMT3A mutation. Integrated analysis divided into four groups: (1) IDH2 and RHOA co-mutation group (7 cases): 6 cases were type Ⅱ, 1 case was type Ⅲ; all with typical TFH phenotype; HRS-like cells and large B transformation were not found; (2) RHOA single mutation group (13 cases): 1 case was type Ⅰ, 6 cases were type Ⅱ, 6 cases were type Ⅲ; 5 cases without typical TFH phenotype; 6 cases had HRS-like cells, and 2 cases with large B transformation. Atypically, 1 case showed TCR-/IG-, 1 case with TCR-/IG+, and 1 case with TCR+/IG+; (3) TET2 and/or DNMT3A mutation alone group (7 cases): 3 cases were type Ⅱ, 4 cases were type Ⅲ, all cases were found with typical TFH phenotype; 2 cases had HRS-like cells, 2 cases with large B transformation, and atypically; (4) non-mutation group (3 cases), all were type Ⅱ, with typical TFH phenotype, with significant extra-GC FDC proliferation, without HRS-like cells and large B transformation. Atypically, 1 case was TCR-/IG-. Univariate analysis confirmed that higher density of EBV positive cell was independent adverse prognostic factors for both overall survival (OS) and progression free survival(PFS), (P=0.017 and P=0.046).
		                        		
		                        			CONCLUSION
		                        			Pathological diagnoses of ALTL cases with HRS-like cells, large B transformation or type Ⅰ are difficult. Although TCR/IG gene rearrangement test is helpful but still with limitation. TES involving RHOA, IDH2, TET2, DNMT3A can robustly assist in the differential diagnosis of those difficult cases. Higher density of EBV positive cells counts in tumor tissue might be an indicator for poor survival.
		                        		
		                        		
		                        		
		                        			Humans
		                        			;
		                        		
		                        			Epstein-Barr Virus Infections/genetics*
		                        			;
		                        		
		                        			Herpesvirus 4, Human/genetics*
		                        			;
		                        		
		                        			T-Lymphocytes, Helper-Inducer/pathology*
		                        			;
		                        		
		                        			Immunoblastic Lymphadenopathy/pathology*
		                        			;
		                        		
		                        			Lymphoma, T-Cell, Peripheral/pathology*
		                        			;
		                        		
		                        			Receptors, Antigen, T-Cell
		                        			
		                        		
		                        	
4.Impact of regional positive lymph node ratio of gallbladder carcinoma on prognosis.
Ye Ming ZHOU ; Hong Chao MI ; Wei JIANG ; Yin JIANG ; Yong Fei HUA ; Chang Jiang LU ; Chun Nian WANG ; Cai De LU
Chinese Journal of Oncology 2022;44(11):1202-1207
		                        		
		                        			
		                        			Objective: To study the impact of regional positive lymph node ratio (LNR) on prognosis of patients with gallbladder carcinoma. Methods: The clinicopathological and survival data of 53 patients with gallbladder carcinoma who underwent radical resection with regional lymph node metastasis in Ningbo University Affiliated Lihuili Hospital from May 2012 to December 2020 were collected, and receiver operating characteristic curve (ROC) was used to determine the optimal cut-off value of LNR for predicting postoperative survival status in patients with gallbladder carcinoma. According to the critical value, the patients were divided into low LNR group and high LNR group. The clinicopathological features and prognosis of the two groups were compared. Log rank test was used for univariate analysis of prognostic factors in patients with gallbladder carcinoma, and Cox proportional hazards model was used for multivariate analysis. Results: A total of 417 regional lymph nodes were dissected in 53 patients, of which 144 lymph nodes were positive, with a positive rate of 34.5%. The optimal cut-off value of LNR for predicting postoperative survival status of patients with gallbladder carcinoma was 0.33. According to this cut-off value, patients were divided into low LNR group (LNR≤0.33, 28 cases) and high LNR group (LNR>0.33, 25 cases). The recurrence rates were 64.3% (18/28) and 88.0 % (22/25) in low LNR group and high LNR group, respectively. The median recurrence-free survival (RFS) was 8 and 7 months, respectively (P=0.032). In the low LNR group, the 1-, 3-, and 5-year survival rates were 56.2%, 38.4%, and 32.0%, respectively, and the median overall survival (OS) was 16 months. In the high LNR group, the 1-, 3-, and 5-year survival rates were 37.9%, 5.4%, and 0, respectively, and the median OS was 9 months. The postoperative survival rate of patients in the low LNR group was better than that in the high LNR group (P=0.008). Univariate analysis showed that LNR was even associated with RFS and OS in patients with gallbladder carcinoma (P<0.05). Multivariate analysis showed that LNR>0.33 was an independent risk factor for postoperative RFS (HR=1.977, 95% CI: 1.045-3.740), but not for OS (HR=1.561, 95% CI: 0.685-3.553). Conclusion: On the basis of clearing a sufficient number of regional lymph nodes, patients with gallbladder carcinoma with regional LNR>0.33 are more likely to relapse after operation, but the predictive value of LNR>0.33 OS is insufficient.
		                        		
		                        		
		                        		
		                        			Humans
		                        			;
		                        		
		                        			Lymph Node Ratio
		                        			;
		                        		
		                        			Gallbladder Neoplasms/pathology*
		                        			;
		                        		
		                        			Lymph Node Excision
		                        			;
		                        		
		                        			Lymphatic Metastasis/pathology*
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		                        			Neoplasm Staging
		                        			;
		                        		
		                        			Retrospective Studies
		                        			;
		                        		
		                        			Lymph Nodes/pathology*
		                        			;
		                        		
		                        			Prognosis
		                        			
		                        		
		                        	
5.Application of limiting antigen avidity enzyme immunoassay for estimating HIV-1 incidence in men who have sex with men.
Xi Jia TANG ; Lei Jing DUAN ; Wen Li LIANG ; Si CHENG ; Ting Li DONG ; Zhen XIE ; Kang Mai LIU ; Fei YU ; Zi Huang CHEN ; Guo Dong MI ; Liang LIANG ; Hong Jing YAN ; Lin CHEN ; Li LIN ; Dian Min KANG ; Xiao Bing FU ; Mao Feng QIU ; Zhen JIANG ; Jie XU ; Zun You WU
Chinese Journal of Epidemiology 2022;43(1):72-77
		                        		
		                        			
		                        			Objective: To estimate the incidence of HIV-1 infection in men who have sex with men (MSM) in key areas of China through HIV-1 limiting antigen avidity enzyme immunoassay (LAg-Avidity EIA), analyze the deviation from the actual results and identify influencing factors, and provided reference for improving the accuracy of estimation results. Methods: Based on the principle of the cohort randomized study design, 20 cities were selected in China based on population size and the number of HIV-positive MSM. The sample size was estimated to be 700 according to the HIV-1 infection rate in MSM. MSM mobile phone app. was used to establish a detection appointment and questionnaire system, and the baseline cross-sectional survey was conducted from April to November 2019. LAg-Avidity EIA was used to identify the recent infected samples. The incidence of HIV-1 infection was calculated and then adjusted based on the estimation formula designed by WHO. The influencing factors were identified by analyzing the sample collection and detection processes. Results: Among the 10 650 blood samples from the participants, 799 were HIV-positive in initial screening, in which 198 samples (24.78%) missed during confirmation test. Only 621 samples were received by the laboratory. After excluding misreported samples, 520 samples were qualified for testing. A total of 155 samples were eventually determined as recent infection through LAg-Avidity EIA; Based on the estimation formula , the incidence of HIV-1 infection in MSM in 20 cities was 4.06% (95%CI:3.27%-4.85%), it increased to 5.53% (95%CI: 4.45%-6.60%)after the adjusting for sample missing rate. When the sample missing rate and misreporting rate were both adjusted, the incidence of HIV-1 infection in the MSM increased to 5.66% (95%CI:4.67%-6.65%). The actual incidence of HIV-1 infection in MSM in the 20 cities might be between 4.06% and 5.66%. Conclusions: Sample missing and misreporting might cause the deviation of the estimation of HIV-1 infection incidence. It is important to ensure the sample source and the quality of sample collection and detection to reduce the deviation in the estimation of HIV-1 infection incidence.
		                        		
		                        		
		                        		
		                        			Cross-Sectional Studies
		                        			;
		                        		
		                        			HIV Infections/epidemiology*
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		                        			HIV-1
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		                        			Homosexuality, Male
		                        			;
		                        		
		                        			Humans
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		                        			Immunoenzyme Techniques
		                        			;
		                        		
		                        			Incidence
		                        			;
		                        		
		                        			Male
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		                        			Sexual and Gender Minorities
		                        			
		                        		
		                        	
6.Human Serum-derived Extracellular Vesicles Protect A549 from PM
Qiu Lian ZHOU ; Yu Zheng BAI ; Juan GAO ; Yi DUAN ; Yi Cheng LYU ; Long Fei GUAN ; Kenneth ELKIN ; Yu Ling XIE ; Zheng JIAO ; Hong Yun WANG
Biomedical and Environmental Sciences 2021;34(1):40-49
		                        		
		                        			Objective:
		                        			Epidemiological studies reveal that exposure to fine particulate matter (aerodynamic diameter ≤ 2.5 μm, PM 
		                        		
		                        			Methods:
		                        			EVs were isolated from the serum of healthy subjects, quantified 
		                        		
		                        			Results:
		                        			PM 
		                        		
		                        			Conclusions
		                        			EVs treatment promotes cell survival and attenuates PM
		                        		
		                        		
		                        		
		                        			A549 Cells
		                        			;
		                        		
		                        			Air Pollutants/toxicity*
		                        			;
		                        		
		                        			Apoptosis/drug effects*
		                        			;
		                        		
		                        			Cell Survival/drug effects*
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		                        			Extracellular Vesicles
		                        			;
		                        		
		                        			Humans
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		                        			Male
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		                        			Middle Aged
		                        			;
		                        		
		                        			Particulate Matter/toxicity*
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		                        			Protective Agents/pharmacology*
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		                        			Proto-Oncogene Proteins c-akt/metabolism*
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		                        			Serum
		                        			
		                        		
		                        	
7.Status of microbiological reports at partial provincial level annual academic conference of healthcare-associated infection from 2015 to 2017
Xiang CHEN ; Bi-Jie HU ; Xiao-Dong GAO ; Qing-Feng SHI ; Yan SHEN ; Wei SUN ; Yang-Wen CUI ; Hong-Fei MI
Chinese Journal of Infection Control 2019;18(3):267-270
		                        		
		                        			
		                        			Objective To understand the present status of special reports relating to microbiology at China provincial-level annual academic conference of healthcare-associated infection (HAI), and provide basis for the training and capacity-building of HAI management staff.Methods The conference arrangements for annual academic conference of provincial HAI quality control centers and HAI management societies from January 2015 to May 2017 were collected, and the special reports on microbiology were summarized and analyzed.Results A total of 35 annual academic conferences held by 17 provinces/municipalities directly under the central government/autonomous regions were included in the study, most conferences (42.31%) were concentrated on the fourth quarter. 15 annual academic conferences were related to microbiology report, accounting for 5.91% of the total reports, reporting time accounted for 4.81% of total time. There were various forms of microbiological thematic reports, subject reports, literature exchange, and interactive exchange accounted for 68.96%, 24.14%, and 6.90% respectively. The proportion of topics related to microbiology reports increased to a certain extent, but the proportion of reporting time decreased.Conclusion At present, the proportion and reporting time of microbiology reports in China provincial-level annual academic conference of HAI is relatively low, it is necessary to increase the number of microbiology reports in the future annual conference of HAI.
		                        		
		                        		
		                        		
		                        	
8.Brucine inhibits bone metastasis of breast cancer cells by suppressing Jagged1/Notch1 signaling pathways.
Ke-Fei HU ; Xiang-Ying KONG ; Mi-Cun ZHONG ; Hong-Ye WAN ; Na LIN ; Xiao-Hua PEI
Chinese journal of integrative medicine 2017;23(2):110-116
OBJECTIVETo examine the effects of brucine on the invasion, migration and bone resorption of receptor activator of nuclear factor-kappa B ligand (RANKL)-induced osteoclastogenesis.
METHODSThe osteoclastogenesis model was builded by co-culturing human breast tumor MDA-MB-231 and mouse RAW264.7 macrophages cells. RANKL (50 ng/mL) and macrophage-colony stimulating factor (50 ng/mL) were added to this system, followed by treatment with brucine (0.02, 0.04 and 0.08 mmol/L), or 10 μmol/L zoledronic acid as positive control. The migration and bone resorption were measured by transwell assay and in vitro bone resorption assay. The protein expressions of Jagged1 and Notch1 were investigated by Western blot. The expressions of transforming growth factor-β1 (TGF-β1), nuclear factor-kappa B (NF-κB) and Hes1 were determined by enzyme-linked immunosorbent assay.
RESULTSCompared with the model group, brucine led to a dose-dependent decrease on migration of MDA-MB-231 cells, inhibited RANKL-induced osteoclastogenesis and bone resorption of RAW264.7 cells (P<0.01). Furthermore, brucine decreased the protein levels of Jagged1 and Notch1 in MDA-MB-231 cells and RAW264.7 cells co-cultured system as well as the expressions of TGF-β1, NF-κB and Hes1 (P<0.05 or P<0.01).
CONCLUSIONBrucine may inhibit osteoclastogenesis by suppressing Jagged1/Notch1 signaling pathways.
Animals ; Bone Neoplasms ; metabolism ; prevention & control ; secondary ; Breast Neoplasms ; drug therapy ; metabolism ; pathology ; Cell Differentiation ; drug effects ; Cells, Cultured ; Female ; Humans ; Jagged-1 Protein ; metabolism ; Macrophages ; drug effects ; physiology ; Mice ; Osteoclasts ; drug effects ; physiology ; Receptor, Notch1 ; metabolism ; Signal Transduction ; drug effects ; Strychnine ; analogs & derivatives ; pharmacology ; therapeutic use
9.Oral health status in Sichuan Province:findings from the oral health survey of Sichuan, 2015–2016
Yin WEI ; Yang YING-MING ; Chen HONG ; Li XUE ; Wang ZHUO ; Cheng LI ; Yin QIU-DAN ; Fang HONG-ZHI ; Fei WEI ; Mi FANG-LIN ; Nie MIN-HAI ; Hu TAO ; Zhou XUE-DONG
International Journal of Oral Science 2017;9(1):10-15
		                        		
		                        			
		                        			To investigate oral health status in the residents of Sichuan Province, southwest China, a cross-sectional study was performed using the latest Oral Health Survey Basic Methods recommended by the World Health Organization. A multistage stratified random cluster-sampling method was used to enroll participants from the following three groups: children aged 3–5 years, adolescents aged 12 years, and people aged 65–74 years. In these three groups, the mean numbers of teeth that were affected by caries were 3.28, 0.86 and 5.13, respectively, resulting in a prevalence of 63.47%, 37.20%and 83.20%, respectively. Relative to the high rate of decayed teeth, the prevalence of fillings was very low in all age groups (0.97%, 7.24% and 5.43%, respectively). In the 12-year-old adolescent group, only 3.61%had good pit and fissure sealing. In addition, the rate of dental fluorosis was 24.80%, and the Community Fluorosis Index value was 0.39. In the elder group, the community periodontal index was 2.92. The prevalence in the elderly of having lost at least one tooth was 75.54%. Additionally, 4.44%of these participants were edentulous. The incidence of dental prosthesis was 51.75%, the proportion with a removable partial denture, a fixed denture, full dentures, dental implants and an informal fixed bridge was 21.59%, 11.45%, 4.64%, 0 and 16.67%, respectively. In this study, 8.2%of the elderly participants were affected by different types of oral mucosal lesions. Among such lesions, recurrent aphthous ulcers were most prevalent (2.69%) and oral lichen planuses were second (1.6%). The conclusion presented in this survey is that oral diseases, especially dental caries and periodontal disease, are frequent and common in Sichuan province, China. Moreover, the treatment rate is very low, and primary prevention and treatment options are therefore urgently needed in this population.
		                        		
		                        		
		                        		
		                        	
10.High intracellular Mg²⁺ affects the activities of L-type calcium channel in guinea- pig ventricular myocytes.
Mei-Mi ZHAO ; Wen-Wen LIAN ; Rui SUN ; Hong-Mei WANG ; Rui FENG ; Hui-Yuan HU ; Xue-Fei SUN ; Li-Ying HAO
Acta Physiologica Sinica 2014;66(6):718-722
		                        		
		                        			
		                        			This study is aimed to investigate the effects of high intracellular Mg²⁺ on L-type calcium channel in guinea-pig ventricular myocytes. The cardiomyocytes were acutely isolated with enzyme digestion method. By adopting inside-out configuration of patch clamp technique, single channel currents of the L-type calcium channel were recorded under different intracellular Mg²⁺ concentrations ([Mg²⁺]i). In control group, which was treated with 0.9 mmol/L Mg²⁺, the relative activity of calcium channel was (176.5 ± 34.1)% (n = 7). When [Mg²⁺]i was increased from 0.9 to 8.1 mmol/L (high Mg²⁺ group), the relative activities of calcium channel decreased to (64.8 ± 18.1)% (n = 6, P < 0.05). Moreover, under 8.1 mmol/L Mg²⁺, the mean open time of calcium channel was shortened to about 25% of that under control condition (P < 0.05), but the mean close time of calcium channel was not altered. These results suggest that high intracellular Mg²⁺ may inhibit the activities of L-type calcium channel, which is mainly due to the shortening of the mean open time of single L-type calcium channel.
		                        		
		                        		
		                        		
		                        			Animals
		                        			;
		                        		
		                        			Calcium Channels, L-Type
		                        			;
		                        		
		                        			physiology
		                        			;
		                        		
		                        			Guinea Pigs
		                        			;
		                        		
		                        			Magnesium
		                        			;
		                        		
		                        			physiology
		                        			;
		                        		
		                        			Myocytes, Cardiac
		                        			;
		                        		
		                        			physiology
		                        			;
		                        		
		                        			Patch-Clamp Techniques
		                        			
		                        		
		                        	
            
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