Kick effect of enzymes causes filament compression.

We investigate the influence of enzymes on the structure and dynamics of a filament by dissipative particle dynamics simulations. Enzyme exerts a kick force on the filament monomer. We pay particular attention to two factors: the magnitude of kick force and enzyme concentration. Large kick force as well as high enzyme concentration prefers a remarkable compression of the filament reminiscent of the effective depletion interaction owing to an effective increase in enzyme size and the reduction of solvent quality. Additionally, the kick effect gives rise to an increase of enzyme density from the center-of-mass of the filament to its periphery. Moreover, the increase of enzyme concentration and kick force also causes a decrease in relaxation time. Our finding is helpful to understand the role of catalytic force in chemo-mechano-biological function and the filament behavior under chemical reaction via kick-induced change of solvent quality.

Role of mitochondrial dynamic-related protein 1 on inflammation after intracerebral hemorrhage in mice / 中国免疫学杂志

Objective:To investigate the effect and mechanisms of mitochondrial dynamic-related protein 1(Drp1)on the in-flammatory response after intracerebral hemorrhage(ICH)in mice.Methods:Western blot was used to detect the expressions of Drp1 and phosphorylated Drp1(p-Drp1)in brain tissues after ICH,and the optimal concentration of selective Drp1 inhibitor(Mdivi-1)were screened.The mice were randomly divided into sham group,ICH group,ICH+solvent control group(ICH+Vehicle group)and ICH+Mdivi-1 group.The neurological function was evaluated by mNSS,the content of brain water was measured by wet-dry weight method,HE and Nissl staining were used to observe the morphological changes of brain tissues,neutrophil infiltration were observed by MPO staining,and the expression of inflammatory cytokines(IL-6,TNF-α)and mitochondrial membrane marker proteins TOM20,COX4Ⅰ1 were detected by Western blot.Results:Compared with sham group,the expression of p-Drp1 was significantly increased at 12 h after ICH(P<0.01).Compared with ICH+Vehicle group,the neurological function score(P<0.01)and brain water content(P<0.05)of ICH+Mdivi-1 group were increased,the protein expressions of IL-6 and TNF-α and the number of MPO positive cells around hematoma in ICH+Mdivi-1 group were significantly increased(P<0.05),and the expressions of mitochondrial membrane proteins TOM20 and COX4Ⅰ1 in ICH+Mdivi-1 group were significantly elevated(P<0.01).Conclusion:Inhibition of Drp1 can inhibit mito-chondrial division and aggravate inflammatory injury after ICH in mice.Therefore,Drp1 may reduce the inflammation after ICH.

Study on extraction technology for Sihuang Shaoshang ointment based on HPLC fingerprint and principal component analysis / 中国药师

Objective To optimize extraction technology for Sihuang Shaoshang ointment by orthogonal test,and establish the HPLC fingerprint of Sihuang Shaoshang ointment to provide references for the quality evaluation of the preparation.Methods Taking Sihuang Shaoshang ointment as the model drug,the fingerprints were established by HPLC method,the common peak areas were analyzed by principal component analysis,and the total factor scores were used as the evaluation index.The technological parameters such as extraction times,extraction time and liquid-solid ratio were optimized by orthogonal test,and the optimal extraction process parameters were screened out.Results The common mode of fingerprint was set up with 12 common peaks and the two principle components with the accumulative contribution rate of 84.751% extracted by principal component analysis were screened out to calculate the comprehensive scores of 9 samples.The optimal extraction process was as follows:10-fold amount of water,extracting 3 times,and extracting 2 h for each time.Conclusion The established method is simple and effective,which can provide a reference for the extraction process optimization of Sihuang Shaoshang ointment.

PRAS40 Connects Microenvironmental Stress Signaling to Exosome-Mediated Secretion.

Secreted exosomes carrying lipids, proteins, and nucleic acids conduct cell-cell communications within the microenvironment of both physiological and pathological conditions. Exosome secretion is triggered by extracellular or intracellular stress signals. Little is known, however, about the signal transduction between stress cues and exosome secretion. To identify the linker protein, we took advantage of a unique finding in human keratinocytes. In these cells, although transforming growth factor alpha (TGF-α) and epidermal growth factor (EGF) share the same EGF receptor and previously indistinguishable intracellular signaling networks, only TGF-α stimulation causes exosome-mediated secretion. However, deduction of EGF-activated pathways from TGFα-activated pathways in the same cells allowed us to identify the proline-rich Akt substrate of 40 kDa (PRAS40) as the unique downstream effector of TGF-α but not EGF signaling via threonine 308-phosphorylated Akt. PRAS40 knockdown (KD) or PRAS40 dominant-negative (DN) mutant overexpression blocks not only TGF-α- but also hypoxia- and H2O2-induced exosome secretion in a variety of normal and tumor cells. Site-directed mutagenesis and gene rescue studies show that Akt-mediated activation of PRAS40 via threonine 246 phosphorylation is both necessary and sufficient to cause exosome secretion without affecting the endoplasmic reticulum/Golgi pathway. Identification of PRAS40 as a linker protein paves the way for understanding how stress regulates exosome secretion under pathophysiological conditions.

Analysis of clinical features of rosacea and rediscussion of a Chinese diagnostic criterion for rosacea / 中华皮肤科杂志

Objective:To propose a Chinese diagnostic criterion for rosacea on the basis of clinical feature analysis of rosacea, and to assess its sensitivity and specificity.Methods:A total of 3 350 Chinese patients with newly diagnosed rosacea were collected from Department of Dermatology, Xiangya Hospital, Central South University between December 2017 and July 2018, their phenotypes and clinical features were retrospectively analyzed, and a Chinese modified diagnostic criterion for rosacea was put forward. A national multi-center clinical observational trial, which included 2 269 patients with rosacea and 2 408 patients with other facial skin diseases from 28 centers, was conducted to verify this diagnostic criterion. Then, the sensitivity and specificity of the modified diagnostic criterion were evaluated by comparing with the 2017 standard classification of rosacea developed by the National Rosacea Society Expert Committee (NRSEC) .Results:Fixed centrofacial erythema occurred in 3 350 (100%) patients with rosacea. Flushing occurred before or simultaneously with fixed erythema in 1 850 (99.4%) of the 1 861 patients with erythema on the cheeks; among the 1 489 patients with erythema on the nose or perioral area, only 52 (3.5%) had flushing; all the 342 patients presenting with phymatous changes had fixed erythema before phymatous changes. Based on the above clinical findings, it was proposed that patients with periodically aggravated fixed erythema on the cheeks accompanied with flushing could be diagnosed with rosacea; patients with fixed erythema on the nose and perioral area accompanied with at least one of selective phenotypes (flushing, telangiectasia, papules and pustules, phymatous changes, or ocular manifestations) could be diagnosed with rosacea. The national multi-center clinical observational trial revealed that the sensitivity of the Chinese modified diagnostic criterion for rosacea was 99.6%, which was close to the sensitivity (100%) of the NRSEC standard, and its specificity was 91.9%, higher than the specificity (73.3%) of the NRSEC standard.Conclusion:The Chinese modified diagnostic criterion for rosacea has good sensitivity and specificity, and can facilitate the early diagnosis of phymatous rosacea.

A comparative split-face study of invasive microneedle radiofrequency versus plasma fractional radiofrequency in the treatment of atrophic acne scars / 中华皮肤科杂志

Objective To compare the clinical efficacy and safety of invasive microneedle radiofrequency versus plasma fractional radiofrequency in the treatment of atrophic facial acne scars.Methods A total of 30 patients with atrophic acne scars were enrolled from the Department of Dermatology of Xiangya Hospital affiliated to Central South University between January 2017 and March 2017.By a random number table,every patient randomly received the treatment with invasive microneedle radiofrequency on one half of the face and plasma fractional radiofrequency on the other facial side once every 8-12 weeks for 3 sessions.Before and after each treatment,facial photos were taken,acne scars were scored by the ECCA grading scale (échelle d'évaluation clinique des cicatrices d'acné),and improvement rates of these lesions were evaluated subjectively by doctors.Adverse reactions were recorded after treatment,and the degree of pain and satisfaction was evaluated by the patients themselves.The Germany CK physiological index detector was used to detect the skin moisture content,transepidermal water loss (TEWL) and sebum content.Results All of the 30 patients completed 3 sessions of treatment and follow-up.After the 3 sessions of treatment,the average score on invasive microneedle radiofrequency-treated sides was 3.00 ± 0.91,and 22 patients achieved more than 50％ improvement.However,the average score on plasma fractional radiofrequency-treated sides was 3.57 ± 0.57,and 29 patients achieved more than 50％ improvement.The overall therapeutic effect of plasma fractional radiofrequency was significantly superior tothat of invasive microneedle radiofrequency (t =2.894,P =0.005).For V-shaped and U-shaped scars,there was no significant difference in the overall improvement rate between the invasive microneedle radiofrequency-treated side and plasma fractional radiofrequency-treated side (both P ＞ 0.05).For Mshaped rolling scars,the overall improvement rate was significantly lower on the invasive microneedle radiofrequency-treated side (36.5％ ± 2.1％) than on the plasma fractional radiofrequency-treated side (48.7％ ± 3.4％,P ＜ 0.01).However,the pain score was significantly lower on the invasive microneedle radiofrequency-treated side (5.54 ± 0.57) than on the plasma fractional radiofrequency-treated side (8.07 ± 0.79,P ＜ 0.01).After 3 sessions of treatment,there were no significant differences in the degree of patient satisfaction (x2 =0.10,P ＞ 0.05),skin moisture content (P ＞ 0.05),TEWL (P ＞ 0.05) or sebum content (P ＞ 0.05) between the 2 sides.Adverse reactions such as erythema,exudation and hemorrhage occurred on both of the 2 sides.Conclusions For small V-shaped and U-shaped scars,the plasma fractional radiofrequency and invasive microneedle radiofrequency both can be applied in clinic.For large M-shaped rolling scars,the plasma fractional radiofrequency can be preferentially selected.

Protective role of AQP3 in UVA-induced NHSFs apoptosis via Bcl2 up-regulation.

Aquaporin-3 (AQP3), a water/glycerol-transporting protein that facilitates water, urea, and glycerol transport, can inhibit arsenite-induced apoptosis by up-regulating Bcl-2. However, whether it has a protective role in ultraviolet A (UVA)-induced apoptosis in normal human skin fibroblasts is not known. In this study, we demonstrate that mild UVA treatment fails to induce oxidative cell stress and apoptosis in normal human skin fibroblasts (NHSFs) overexpressing AQP3. After severe UVA irradiation, there was an increase in oxidative cell stress and apoptosis when AQP3 levels decreased. We also found that silencing AQP3 sensitized NHSFs to low-dose UVA. Overexpressing AQP3 was protective against high-dose UVA-induced oxidative stress and apoptosis. Besides, we observed that Bcl-2 may be involved in UVA-induced apoptosis. Our findings suggested that the water/glycerol-transporting protein AQP3 plays a role in resistance to UVA-induced apoptosis.

Clinical analysis of 1 090 cases of rosacea and exploration of new diagnostic criteria for rosacea / 中华皮肤科杂志

Objective To propose a new diagnostic criterion for rosacea based on the analysis of clinical features of rosacea in a large sample.Methods A total of 1 090 Chinese outpatients with rosacea were enrolled from Department of Dermatology of Xiangya Hospital,and their demographic data,clinical manifestations and subjective symptoms were collected.According to results of descriptive analysis,clinical features of rosacea were summarized,and a new diagnostic criterion for rosacea was set up.Then,the sensitivity and specificity of the new diagnostic criterion were verified among 1 200 outpatients clinically characterized by facial erythema.Results Of 1 090 patients with rosacea,131 (12.0％) were male and 959(88.0％) were female,and the average age was 33.5 ± 11.1 years (range,10-66).Among the 1 090 patients,715 (65.6％) had initial lesions on the cheek,of whom,712 (99.6％) had intermittent flushing as the initial symptom,and 689 (96％) had sensitive skin symptoms such as dryness,burning and itching sensations;208 (19.1％) had initial lesions on the perioral region,of whom,204 (98.1％) had persistent erythema as the initial symptom;167 (15.3％) had initial lesions on the nose,of whom,163 (97.6％) had persistent erythema as the initial symptom;in addition,311 (28.5％) had lesions on the ocular region,and only 24 (2.2％) had lesions outside the face on the neck and retroauricular region.Based on these clinical features,a new diagnostic criterion for rosacea was proposed,including 1 major condition (intermittent flushing or persistent erythema on the cheek,perioral region or nose) and 5 minor conditions (1.sensitive skin symptoms such as burning,tingling,drying or itching sensations;2.telangiectasia;3.papules or pustules;4.hypertrophy;5.ocular symptoms).If with the major condition and at least one minor condition were met,patients could be diagnosed with rosacea.After verification among 1 200 patients with facial dermatitis clinically characterized by facial erythema,the new criterion was proved to have a sensitivity of 99.3％ and a specificity of 95.8％.Conclusion A new diagnostic criterion for rosacea with high sensitivity and specificity is proposed,which is worthy of clinical application.

Expression of cyclophilin A and CD147 during skin aging / 中南大学学报(医学版)

Objective To investigate the role of cyclophilin A (CypA) and CD147 in the process of skin aging. Methods Twenty cases of tissue samples from junior group(＜15 years old), middle age group(30-40 years old)or old age group (＞65 years old) were collected from photophobic and exposal parts of skin, respectively. Immunohistochemistry (IHC) and in situ hybridization (ISH) were carried out to semi-quantitatively detect the expression level of CyPA and CD147. Results IHC demonstrated that both CyPA and CD147 were expressed in both photophobic and exposal parts of normal human skin in all 3 groups. The expression levels of both CyPA and CD147 were increased with increase in age. There were significant differences in both CyPA and CD147 expression among 3 groups (P<0.05). CyPA and CD147 were also positively correlated in all 3 groups. Similar results were achieved by ISH. Conclusion The interaction between CD147 and CyPA might play an important role in the process of skin aging.

A survey on AIDS knowledge rate and sexual behavior among men who have sex with men population at sexually transmitted disease clinic / 中南大学学报(医学版)

OBJECTIVE@#To survey on men who have sex with men (MSM) population's sexual behaviors, condom-service condition, HIV related knowledge and other issues among MSM population at sexually transmitted disease (STD) clinics to understand the characteristics of behaviors and offer suggestions for effective health education and behavior intervention.@*METHODS@#From January to December, 2009, we used anonymous questionnaires which involved in their mastery of demographic characteristics, sexual behavior, condom-service condition, HIV related knowledge, and so one, to investigate 200 MSM at 3 STD clinics of comprehensive hospital.@*RESULTS@#The average age of informant was (26.7+/- 8.9) years and 121 individuals (62.6%) had confirmed with STD in recent one year. In the recent 6 months, the average number of homosexual partners was 9.2+/- 4.8 and 102 (52.8%) had heterosexual partners. In the sexual intercourse with homosexual, 123 individuals had anal intercourse (63.7 %) and 117 had oral intercourse (60.6%). In the sexual intercourse with heterosexual, 92 (90.2%) individuals had vaginal intercourse, 37 (36.2%) had anal intercourse, and 59 (57.8%) had oral sex behavior.There were a statistical difference between heterosexual and homosexual sex behaviors (P<0.01). The condom-using frequency had statistic difference in different sexual behaviors(χ²=188.396, P<0.001). There was no linear correlation between HIV related knowledge and condom-using condition in sexual behaviors except the heterosexual anal intercourse.@*CONCLUSION@#High AIDS knowledge mastery rate is found in our survey. The respondents get HIV/AIDS knowledge through various ways actively. There is no obvious relation between the mastery of HIV related knowledge and condom-using frequency. The ratio of non-protected sexual behaviors is high in heterosexuals. How to adopt effective methods for behavior intervention to MSM at STD clinic needs to be further studied.

Effect of triptolide on the proliferation and apoptosis of human epidermal squamous cell carcinoma cell line A431 in vitro / 中南大学学报(医学版)

Objective To investigate the effect of triptolide on the proliferation and apoptosis of human epidermal squamous cell carcinoma cell line A431 in vitro. Methods Human epidermal squamous cell carcinoma cell line A431 was cultured. After the treatment with triptolide, the inhibi-tion of cellular growth was determined by measuring MTT dye absorption of the living cells. Light mi-croscope showed morphological changes. The cell cycle and apoptosis rate were assessed by flow cy-tometry. Results Triptolide could significantly inhibit the proliferation of A431 cells in a dose- and time-dependent manner. Triptolide could also cause cell morphological changes ( the number of float-ing cells and nuclear pyknosis increase), induce cell apoptosis, and change the distribution of cell cycle phase in A431 cells. Compared with the control group, the G0/G1 phase A431 cell rate in-creased and the rate of S phase cell decreased in TP-treated group. Cell cycles were obviously inhibi-ted by triptolide in G0/G1 phase (both P<0.05). Conclusion TP could play an anti-tumor role by effectively inducing cell apoptosis and inhibiting the proliferation of A431 cells.

Protective effect of resveratrol on UVA-irradiated human keratinocyte cell line and its mechanism / 中华皮肤科杂志

Objective To observe the protection of human keratinocyte cell line, HaCaT cell, from UVA damage by resveratrol and its possible mechanism. Methods HaCaT cells were incubated with or without 0.01 mmol/L or 0.1 mmol/L resveratrol after exposure to 5 J/cm2 UVA irradiation. Unirradiated HaCaT cells-without the treatment with resveratrol served as the control. After another 24-hour culture, MTT assay was used to detect the proliferation of cells, RT-PCR and Western-blot to measure the iNOS mRNA and protein expression respectively, electron microscopic technique to observe the changes in cell ultrastructure. Results After irradiation with UVA of 5 J/cm2, the proliferation of HaCaT cells decreased with the absorbance at 490 nm descending from 0.889±0.083 to 0.542±0.004, while a significant increase was observed in the relative expression level of iNOS mRNA and protein in HaCaT cells (1.532±0.041 vs 0.009±0.003, 1.331 ±0.046 vs 0.003±0.001, both P < 0.05) with the presence of typical apoptotic cells. The treatment with 0.01 and 0.1 mmol/L resveratrol significantly promoted the proliferation of irradiated cells with the absorbance at 490 nm being 0.753±0.435 and 0.892±0.173 respectively, but inhibited the mRNA (0.853±0.038 vs 1.532±0.041, 0.392±0.033 vs 1.532±0.041, both P< 0.05) and protein expression level (0.809±0.018 vs 1.331±0.046, 0.412±0.026 vs 1.331±0.046, both P< 0.05) of iNOS in irradiated cells, and the resveratrol of 0.1 mmol/L was more effective than that ofO.01 mmol/L in all tested parameters (P< 0.05). Furthermore, no apoptofic cells or necrotic cells were observed in irradiated ceils incubated with resveratrol. Conclusion Resveratrol effectively protects HaCaT cells from UVA damage, which may be related to the inhibition of UVA-induced iNOS expression by resveratrol.