Objective:To evaluate the synergistic antibacterial effects of lysozyme with ethylenediami-netetraacetic acid disodium salt (EDTA-2Na) on Enterococcus faecalis (E.faecalis) and Porphyromonas endodontalis ( P.endodontalis) .Methods:E.faecalis and P.endodontalis were cultured and adjusted to 108 CFU/mL.Then 0.3, 0.5, 1, 2, 5, 10, 50, 100, 150 and 300 g/L of lysozyme were prepared with deionized water;and the lysozyme solutions were mixed with 0.5, 1.0, 2.0 g/L of EDTA-2Na, re-spectively.The bacteria and lysosome with/without EDTA-2Na interacted for 15 min, then water-soluble tetrazolium (WST) working solution was added and the activity of the bacteria was calculated by mea-suring optical densities at 450 nm and 630 nm with microplate spectrophotometer .Results:Regarding the pure lysozyme from 0.5 g/L to 150 g/L, more E.faecalis and P.endodontalis were inhibited when the concentration of lysozyme was higher , especially for E.faecalis.There was synergistic effect of lysozyme with EDTA-2Na on antibacterial activity , which was related to the concentration of lysozyme .On E.fae-calis, the antibacterial activity of lysozyme with EDTA-2Na was 1.2-3.7 folds than the pure lysozyme when the concentration of lysozyme was 0.5-50 g/L (P<0.05), and on P.endodontalis, the antibac-terial activity of lysozyme with EDTA-2Na was 1.3 -3.5 folds than the pure lysozyme when the concentration of lysozyme was 0.5-10 g/L (P<0.05).When the concentration of lysozyme was higher than 100 g/L, EDTA-2Na did not show synergistic effect on the antibacterial activity (P>0.05). Conclusion: For E.faecalis and P.endodontalis, a low concentration of lysozyme with EDTA-2Na showed significant synergistic antibacterial activity , while a high concentration of lysozyme with EDTA-2 Na did not .

Teaching model plays an important role in clinical education. Problem based learning (PBL) model, with an outstanding feature of stimulating the learning enthusiasm of students, was applied by many American colleges. American College of Acupuncture&Oriental Medicine (ACAOM) combined PBL teaching model with traditional lecture based learning (LBL) model, which had achieved good results. In this article, PBL model and its characters were explored via qualitative case analysis, to provide reference for universities and colleges of traditional Chinese medicine on clinical education.

Objective To analyze the prevalence and characteristics of skin diseases in elderly patients with type 2 diabetes mellitus (T2DM).Methods Clinical out patient records for both elderly and non-elderly individuals with T2DM were collected from the dermatology department of Beijing Hospital.Statistical comparisons were performed between the elderly group and the non-elderly group on the prevalence of common skin complications and disease characteristics.Analysis was performed in the elderly group to identify any association of common skin disorders with gender,age,duration of T2DM,or level of glycosylated hemoglobin (HbA1c).Results Among 679 elderly T2DM cases,pruritus was the most common complication (26.1％),followed by eczema (21.t ％) and tinea pedis/onychomycosis (18.3％).Pruritus was more prevalent in the elderly group (177 cases,26.1％) compared to the non-elderly group (34 cases,9.8％) (x2 =6.006,P＜0.01).On the other hand,tinea pedis/onychomycosis was less prevalent in the senior group (124 cases,18.3 ％) than in the non-senior group (112 cases,32.2 ％) (x2 =37.437,P＜0.01).In the senior group,pruritus was more prevalent among male patients (105 out of 358 cases,29.3％) than among female patients(72 out of 321 cases,22.4％) (x2 =4.181,P =0.041).On average,patients with eczema were older[(72.3 ± 2.2)years] and had a longer history of T2DM [(8.3 ± 0.3)years] compared with patients without eczema[age:(65.2±1.9)years,history of T2DM:(5.2±0.1)years] (t=1.250,P=0.023 for age;t=1.680,P=0.033 for disease duration).Patients with tinea pedis/onychomycosis had higher HbA1c levels (6.7 ± 0.4) ％ than patients without tinea pedis/onychomycosis (6.1 ± 0.3) ％ (t =0.790,P＜0.01).Conclusions Pruritus is the most common skin complication in elderly patients with type 2 diabetes and is more common in elderly patients and male patients.Risk factors for developing eczema in elderly patients with type 2 diabetes may include older age and long disease duration.High levels of glycosylated hemoglobin in elderly patients with type 2 diabetes indicates increased risk for foot fungi infections.

Objective To investigate clinical features and therapeutic protocols of vulvovaginal-gingival syndrome(VVGS). Methods Clinical data were collected from 11 female patients with VVGS and analyzed. Results Among the 11 patients, the mean and median ages at a definite diagnosis of VVGS were both 46 years, and the average disease duration was 4 years. Painful erosive erythema was found on the vaginal vestibule in 7 patients, on the gingiva in 10, as well as on the bilateral buccal mucosa in 5. Additionally, 8 and 4 patients reported dyspareunia and vaginal hemorrhage, respectively. Seven patients were treated with low-dose oral methylprednisolone combined with hydroxychloroquine or colchicine, and the other 4 were treated with oral hydroxychloroquine alone. Furthermore, all of the 11 patients applied topical tacrolimus 0.1%ointment. Finally, 8 patients were cured or markedly improved. No obvious adverse reactions were observed in any of the patients. Conclusions VVGS mostly occurs in middle-aged women, with the vaginal vestibule and gingiva as predilection sites of painful erythema and dyspareunia as common symptoms. Patients have good responses to methylprednisolone combined with hydroxychloroquine, and hydroxychloroquine alone also shows good efficacy in patients with mild VVGS. Tacrolimus 0.1%ointment can be one of drugs for topical maintenance treatment of VVGS.

Objective To study the discrepancy influence of the sulbactam content on susceptibility testing results of cefoperazone/sulbactam combination disks.Methods Agar dilution method was used to determine MICs of cefoperazone,cefoperazone/sulbactam(2:1 and 1:1),and disk diffusion was used to detect the zone diameters of cefoperazone,cefoperazone/sulbactam(75/30 and 75/75μg/disk)disks against 534 clinical gram-negative isolates.The discrepancy within the results of MICs,zore diameters,the method of agar dilution and disk diffusion was analyzed.Results By standard agar dilution method,MIC_(50) of cefoperazone,cefoperazone/sulbactam(2:1 and 1:1)were 32,16,16μg/ml,and MIC_(90) of those were ≥256.128,64 μg/ml respectively.No statistic discrepancy was found for MICs between the ratios of 2:1 and 1:1 combination by Wilcoxon ranks test(Z=-0.248,P=0.804).Susceptibility rate,resistance rate,and intermediate rate with 75/30μg disk were 55.3%,24.5%and 20.2%respectively,which were similar to those determined by agar dilution method.Susceptibility rate,resistance rate,and intermediate rate(I%)with 75/75μg disk were 72.5%,12.4% and 15.1% respectively,compared with the susceptibility rate from 75/30μg disk was 17.2% higher.Statistic discrepancy were tested by paired t-test (t=21.613,P＜0.01)with two groups of whole strains' zone diameters from 75/30μg and 75/75μg disks,and resulting in the difference of susceptibility or resistance rates for ESBL-producing strains,Acinetobacter bauamnnii and Enterobacteriaceae without ESBL tested isolates.On the contrary,for Pseudomonas aeruginosa,Stenotrophomonas maltophilia and ESBL negative isolates,the zone diameters discrepancy was not statistically significant between the results from 75/30μg and 75/75μg disks.Conclusions There is no statistic discrepancy between the susceptibility results from cefoperazone/sulbactam(2:1 or 1:1 ratios)in dilution method and in diffusion method with 75/30μg disk.When the 75/75μg disk is used to be tested for ESBL-producing strains,Acinetobacter bauamnnii and other Enterobacteriaceae,the results should be shown with sulbactam content.

Objective:To investigate the impact of daily step count on glycemic outcomes in community residents with impaired glucose tolerance (IGT).Methods:This was a prospective cohort study, in October 2018, 204 residents who met the criteria of IGT were recruited in the Shijingshan District in Beijing. The subjects were tested for fasting blood glucose, oral glucose tolerance test 2-hour blood glucose (2hBG), glycated hemoglobin A 1c (HbA 1c), lipid profile, liver and kidney function, as well as measurements of height, weight and waist circumference. A dedicated mobile application was used to deliver prediabetes health knowledge monthly. Online guidance was provided to answer questions and daily step count was collected using the application. Three years later, a follow-up was conducted to assess the participants′ glycemic outcomes and other indexes, and a total of 142 participants completed the follow-up review. According to daily step count, the subjects were categorized into high step count group (42 cases,>7 000 steps daily), moderate step count group (54 cases, 5 000-7 000 steps daily), and low step count group (46 cases,<5 000 steps daily). Subjects were categorized into diabetes group (30 cases), prediabetes group (77 cases) and normal glucose tolerance group (35 cases) with glycemic outcomes. Independent sample t test was used to compare the differences in blood glucose, blood lipids, and step counts between the two groups. Kruskal-Wallis H test or one-way ANOVA was used to compare the differences in blood glucose, blood lipids, and step counts between multiple groups. The χ2 test was used to compare the differences in glycemic outcomes between multiple groups. Multivariate logistic regression analysis was used to assess the impact of daily step counts and body mass index on glycemic outcomes. Linear regression analysis was used to evaluate the relationship between daily step counts and 2 h BG. Results:A total of 142 participants completed the 3-year follow-up, including 43 males and 99 females, with a mean age of (60.15±5.67) years. At baseline, males had significantly higher body mass index, waist circumference, and fasting blood glucose when compared to those in females [(26.97±2.43) vs (24.89±2.93) kg/m 2, (92.68±7.75) vs (83.83±8.60) cm, (5.83±0.61) vs (5.62±0.52) mmol/L], the total cholesterol and HDL-C were also significantly lower in males than those in females [(5.10±1.16) vs (5.55±0.95) mmol/L, (1.35±0.34) vs (1.56±0.35) mmol/L] (all P<0.05). After 3-year follow-up, 21.1% (30/142) of IGT participants progressed to diabetes, with an annual conversion rate of approximately 7%. The normal glucose tolerance group showed significantly higher daily step counts when compared with the prediabetes and diabetes groups [(7 886±2 867) vs (5 981±2 655) vs (4 117±2 674) steps] ( H=31.778, P<0.001). Individuals with higher daily step counts exhibited lower body mass index, 2 h BG, and HbA 1c level when compared with those in the ones with moderate and low step counts [(24.26±3.09) vs (25.44±3.38) vs (26.26±3.59) kg/m 2, (7.50±1.71) vs (9.15±3.30) vs (11.19±3.84) mmol/L, 5.97%±0.46% vs 6.14%±0.99% vs 6.40%±0.96%] (all P<0.05). Higher step count was positively correlated with the reversal of prediabetes to normal blood glucose levels (moderate step count, OR=0.297, 95% CI: 0.109-0.804; low step count, OR=0.055, 95% CI: 0.010-0.287), lower daily step count correlated positively with prediabetes progressing to diabetes ( OR=4.857, 95% CI: 1.140-20.689) (all P<0.05). For every additional 1 000 steps per day, the 2 h BG decreased by 0.5 mmol/L. Conclusion:As daily step count increases, the glucose metabolism improves in IGT community residents. Higher daily step count is associated with reversal of IGT to normal glucose tolerance, while lower daily step count may be associated with the progression of IGT to diabetes.

Objective:To analyze changes in melanocyte density and epidermal thickness in vulvar lichen sclerosus (VLS) lesions.Methods:Vulvar skin tissues were collected from 15 adult female patients with VLS in Department of Dermatology, Beijing Hospital from June to December in 2018. According to pathological manifestations, 15 skin lesions were divided into early-stage VLS group ( n = 7) and late-stage VLS group ( n = 8) , and subjected to immunofluorescent staining. Then, density of melanocytes, and thickness of the whole epidermis and cell layers (from the bottom of the stratum corneum to the bottom of the basal layer) were calculated by using an image analysis software. Normal vulvar skin tissues were obtained from 15 healthy adult females after vulvar plastic surgery in Plastic Surgery Hospital, Chinese Academy of Medical Sciences, and served as control group. Results:The density of melanocytes in the epidermis was significantly lower in the early-stage VLS group (0.170 ± 0.071) and late-stage VLS group (0.110 ± 0.035) than in the control group (0.275 ± 0.036; F = 36.426, P < 0.001) . There was no significant difference in the thickness of the whole epidermis among the early-stage VLS group (203.682 ± 137.997 μm) , late-stage VLS group (150.020 ± 70.914 μm) and control group (194.030 ± 82.996 μm; F = 0.738, P = 0.487) . The thickness of cell layers did not differ between the early-stage VLS group (154.603 ± 121.984 μm) and control group (176.974 ± 80.296 μm; P = 0.899) , but was significantly thinner in the late-stage VLS group (83.455 ± 37.129 μm) than in the control group ( P = 0.003) . Conclusions:The density of epidermal melanocytes decreased in the early-stage and late-stage VLS skin lesions. Compared with the normal skin tissues, the early-stage VLS lesions showed no significant changes in the thickness of the whole epidermis and cell layers, but the late-stage VLS lesions showed decreased thickness of cell layers.

By inserting microRNAs into the intron of EF1α promoter, we constructed a novel lentiviral vector knocking down PD-1 gene via microRNA and applied it to CAR-T cells. Lentiviral transduction efficiency and PD-1-silencing efficiency were detected by flow cytometry. PD-1 expression was detected by Western blotting. Relative expression of microRNA was measured by Q-PCR. Cytotoxicity of CAR-T cells based on this vector was tested by luciferase bioluminescence and flow cytometry. Compared with lentiviral vector with microRNA transcribed by U6 promotor, the transduction efficiency of lentiviral vector with microRNA which was inserted into the intron of EF1α promoter was more significant, and the knockdown rate of PD-1 was more than 90%, which was validated by flow cytometry and Western blotting. And the relative expression level of microRNA in Jurkat cells transduced with this novel lentiviral vector was shown by Q-PCR. Compared with normal CAR-T cells, CAR-T cells based on this vector showed stronger cytotoxicity against PD-L1 positive Raji cells. We successfully constructed a novel lentiviral vector that knocked down PD-1 via microRNA and verified the superiority of its transduction efficiency and knockdown efficiency of PD-1. CAR-T cells based on this vector can exert a more powerful cytotoxicity, thus providing theoretical support for the subsequent treatment of PD-L1 positive tumors.
Cell Line, Tumor ; Gene Knockdown Techniques ; Genetic Vectors ; genetics ; Humans ; Lentivirus ; genetics ; MicroRNAs ; metabolism ; Programmed Cell Death 1 Receptor ; Promoter Regions, Genetic ; genetics

Objective To analyze special histopathological characteristics of melanocytic nevi and their associations with age,gender,anatomical locations and pathological subtypes.Methods Clinical and histopathological data were collected from 1 011 patients with melanocytic nevi,who visited Beijing Hospital from January 2005 to January 2019,and analyzed retrospectively.Statistical analysis was carried out by using chi-square test for comparing enumeration data,and t test for comparing measurement data.Results Among the 1 011 patients with melanocytic nevi,the age at the clinic visit was 40.90 + 19.19years,and there were 289 males and 722 females.Lesional (biopsy) sites included the trunk (402 cases,39.8％),face and neck (268 cases,26.5％),extremities (138 cases,13.6％),hands and feet (133 cases,13.2％),scalp (53 cases,5.2％) and vulva (17 cases,1.7％).Pathological subtypes included intradermal nevus (580 cases,57.4％),compound nevus (333 cases,32.9％) and junctional nevus (98 cases,9.7％).Among special histopathological characteristics,neuralization and adipose cell hyperplasia were observed in 172 (17.0％) and 155 (15.3％) cases respectively,and the prevalence of neuralization and adipose cell hyperplasia was significantly higher in female patients than in male patients,higher in elderly patients than in young patients,and higher on the scalp than on the other sites (all P ＜ 0.05);vascular proliferation was observed in 313 (31.0％) cases,and more commonly occurred on the scalp than on the other sites (P＜0.05);nevus cells distributed along the hair follicles/sebaceous glands were observed in 502 (49.7％)cases,and more commonly seen on the face and neck than on the other sites (P ＜ 0.05);nevus cell lysis occurred in 203 (20.1％) cases,and fissures were observed in 384 (38.0％).All the above histopathological characteristics were more frequently observed in the intradermal nevus subtype than in the compound nevus subtype (all P＜0.05).Nevus cells distributed along the blood vessels were observed in 20 (2.0％) cases,and more commonly seen on the extremities than on the trunk,hands and feet (P ＜ 0.05),as well as in the compound nevus subtype than in the intradermal nevus subtype (P ＜ 0.05).Conclusions There are many special histopathological characteristics in melanocytic nevi,such as neuralization,adipose cell hyperplasia,vascular proliferation,and nevus cells distributed along the hair follicles/sebaceous glands,which are associated with patients' age,gender,lesional locations and histopathological subtypes.

Objective To investigate clinical features of vulvar lichen simplex chronicus (VLSC).Methods Clinical data were collected from 137 VLSC patients who visited a Vulvar Clinic in the Department of Dermatology,Beijing Hospital from 2017 to 2018,and analyzed retrospectively.Non-normally distributed measurement data (age and disease duration) were described as median (P25,P75),and analyzed by using rank sum test,and enumeration data were compared by using chi-square test.Results Among the 137 patients with VLSC,the age at onset was 32.0 (25.5,40.0) years,and the disease duration was 36.0 (15.0,72.0) months.Thirty-two (23.4％) patients had a history of atopic diseases,and the age at onset of VLSC was significantly lower in these patients with a history of atopic diseases (29.5 [25.0,35.8]years) than in those without a history of atopic diseases (33.0 [27.0,41.0] years,Z =2.03,P =0.042).The most frequently involved site was the labia majora (130/137,94.9％),and the labia minora was rarely involved (13/137,9.5％).Bilateral lesions were observed in 103 (75.2％) patients,and hypopigmentation occurred in 8 (5.8％) patients.All the patients experienced itching to different extents,including moderate itching in 44 (32.1％) cases and severe itching in 80 (58.4％).The ratio of patients with severe itching to those with disease duration ＞ 2 years (68.1％) was significantly higher than that of patients with severe itching to those with disease duration ＜ 2 years (47.7％,x2 =5.830,P =0.016).Patients reported that local wetness and sweating (55 cases,40.1％),spicy diet (41 cases,29.9％) and mental stress (36 cases,26.3％) could aggravate itching,Conclusions VLSC commonly occurs in patients aged 20-39 years,and atopic predisposition may be an important factor for VLSC.VLSC mostly involves bilateral labia majora,and the longer the disease duration,the more severe the itching.