1.Polysaccharide of Alocasia cucullata Exerts Antitumor Effect by Regulating Bcl-2, Caspase-3 and ERK1/2 Expressions during Long-Time Administration.
Qi-Chun ZHOU ; Shi-Lin XIAO ; Ru-Kun LIN ; Chan LI ; Zhi-Jie CHEN ; Yi-Fei CHEN ; Chao-Hua LUO ; Zhi-Xian MO ; Ying-Bo LIN
Chinese journal of integrative medicine 2024;30(1):52-61
		                        		
		                        			OBJECTIVE:
		                        			To study the in vitro and in vivo antitumor effects of the polysaccharide of Alocasia cucullata (PAC) and the underlying mechanism.
		                        		
		                        			METHODS:
		                        			B16F10 and 4T1 cells were cultured with PAC of 40 µg/mL, and PAC was withdrawn after 40 days of administration. The cell viability was detected by cell counting kit-8. The expression of Bcl-2 and Caspase-3 proteins were detected by Western blot and the expressions of ERK1/2 mRNA were detected by quantitative real-time polymerase chain reaction (qRT-PCR). A mouse melanoma model was established to study the effect of PAC during long-time administration. Mice were divided into 3 treatment groups: control group treated with saline water, positive control group (LNT group) treated with lentinan at 100 mg/(kg·d), and PAC group treated with PAC at 120 mg/(kg·d). The pathological changes of tumor tissues were observed by hematoxylin-eosin staining. The apoptosis of tumor tissues was detected by TUNEL staining. Bcl-2 and Caspase-3 protein expressions were detected by immunohistochemistry, and the expressions of ERK1/2, JNK1 and p38 mRNA were detected by qRT-PCR.
		                        		
		                        			RESULTS:
		                        			In vitro, no strong inhibitory effects of PAC were found in various tumor cells after 48 or 72 h of administration. Interestingly however, after 40 days of cultivation under PAC, an inhibitory effect on B16F10 cells was found. Correspondingly, the long-time administration of PAC led to downregulation of Bcl-2 protein (P<0.05), up-regulation of Caspase-3 protein (P<0.05) and ERK1 mRNA (P<0.05) in B16F10 cells. The above results were verified by in vivo experiments. In addition, viability of B16F10 cells under long-time administration culture in vitro decreased after drug withdrawal, and similar results were also observed in 4T1 cells.
		                        		
		                        			CONCLUSIONS
		                        			Long-time administration of PAC can significantly inhibit viability and promote apoptosis of tumor cells, and had obvious antitumor effect in tumor-bearing mice.
		                        		
		                        		
		                        		
		                        			Mice
		                        			;
		                        		
		                        			Animals
		                        			;
		                        		
		                        			Alocasia/metabolism*
		                        			;
		                        		
		                        			MAP Kinase Signaling System
		                        			;
		                        		
		                        			Caspase 3/metabolism*
		                        			;
		                        		
		                        			Apoptosis
		                        			;
		                        		
		                        			RNA, Messenger/metabolism*
		                        			
		                        		
		                        	
2.No Incidence of Liver Cancer Was Observed in A Retrospective Study of Patients with Aristolochic Acid Nephropathy.
Tao SU ; Zhi-E FANG ; Yu-Ming GUO ; Chun-Yu WANG ; Jia-Bo WANG ; Dong JI ; Zhao-Fang BAI ; Li YANG ; Xiao-He XIAO
Chinese journal of integrative medicine 2024;30(2):99-106
		                        		
		                        			OBJECTIVE:
		                        			To assess the risk of aristolochic acid (AA)-associated cancer in patients with AA nephropathy (AAN).
		                        		
		                        			METHODS:
		                        			A retrospective study was conducted on patients diagnosed with AAN at Peking University First Hospital from January 1997 to December 2014. Long-term surveillance and follow-up data were analyzed to investigate the influence of different factors on the prevalence of cancer. The primary endpoint was the incidence of liver cancer, and the secondary endpoint was the incidence of urinary cancer during 1 year after taking AA-containing medication to 2014.
		                        		
		                        			RESULTS:
		                        			A total of 337 patients diagnosed with AAN were included in this study. From the initiation of taking AA to the termination of follow-up, 39 patients were diagnosed with cancer. No cases of liver cancer were observed throughout the entire follow-up period, with urinary cancer being the predominant type (34/39, 87.17%). Logistic regression analysis showed that age, follow-up period, and diabetes were potential risk factors, however, the dosage of the drug was not significantly associated with urinary cancer.
		                        		
		                        			CONCLUSIONS
		                        			No cases of liver cancer were observed at the end of follow-up. However, a high prevalence of urinary cancer was observed in AAN patients. Establishing a direct causality between AA and HCC is challenging.
		                        		
		                        		
		                        		
		                        			Humans
		                        			;
		                        		
		                        			Retrospective Studies
		                        			;
		                        		
		                        			Incidence
		                        			;
		                        		
		                        			Carcinoma, Hepatocellular
		                        			;
		                        		
		                        			Liver Neoplasms/epidemiology*
		                        			;
		                        		
		                        			Kidney Diseases/chemically induced*
		                        			;
		                        		
		                        			Aristolochic Acids/adverse effects*
		                        			
		                        		
		                        	
3.Determination of the Contents of Three Lignans in Dendrobium fimbriatum Hook
Ying-Hua HUANG ; Lin ZHANG ; Jin-Yan LI ; Zhi-Bin LI ; Zhi-Yun LIANG ; Li-E YANG ; Gang WEI ; Yue-Chun HUANG
Journal of Guangzhou University of Traditional Chinese Medicine 2024;41(1):207-212
		                        		
		                        			
		                        			Objective To establish the method for content determination of three lignans of Dendrobium Fimbriatum Hook..Methods The lignans in Dendrobium tasselii were identified by high-performance liquid chromatography/multi-stage mass spectrometry(HPLC-ESI/MSn)coupled with ultraviolet absorption spectrometry(UV)coupled with retention time localization of high-performance liquid chromatography(HPLC).The separation was carried out on a Kromasil 100-5 C18 column(4.6 mm×250 mm,5 μm)using a gradient elution of acetonitrile-0.1%formic acid solution as the mobile phase,the volume flow rate was 0.8 mL·min-1 and the column temperature was 35℃,and the mass spectrometry was performed using an ESI ion source with the data collected in the negative ion mode.The HPLC content was determined on the same column as that of MS analysis,with the mobile phase methanol + acetonitrile(V/V=1∶1)-0.01 mol/L ammonium acetate solution,gradient elution,flow rate of 0.8 mL·min-1,column temperature of 40℃,and detection wavelength of 215 nm.Results Syringaresinol di-O-glucoside and(-)-Syringaresinol 4-O-β-D-glucopyranoside and DL-Syringaresinol were identified from Dendrobium fimbriatum Hook.,and the results of content determination showed that the linear ranges of above three components were respectively 0.1701-3.4020,0.1020-2.0400,0.0403-0.8060 μg(r≥0.9995),the average recoveries were in the range of 97.71%-101.67%,and the relative standard deviations(RSDs)were all less than 3.0%.The contents of Syringaresinol di-O-glucoside and(-)-Syringaresinol 4-O-β-D-glucopyranoside and DL-Syringaresinol in the 10 batches of samples were 0.7779-1.3852,0.0734-0.1966,0.0295-0.1882 mg·g-1.Conclusion This research method can provide a reference basis for the quality evaluation method of Dendrobium fimbriatum Hook..
		                        		
		                        		
		                        		
		                        	
4.High tibial osteotomy on varus knee osteoarthritis with medial meniscus posterior root injury
Chun-Jiu WANG ; Xiang-Dong TIAN ; Ye-Tong TAN ; Zhi-Peng XUE ; Wei ZHANG ; Xiao-Min LI ; Ang LIU
China Journal of Orthopaedics and Traumatology 2024;37(9):886-892
		                        		
		                        			
		                        			Objective To explore clinical effect of distal tibial tubercle-high tibial osteotomy(DTT-HTO)in treating knee osteoarthritis(KO A)with medial meniscus posterior root tear(MMPRT).Methods A retrospective analysis was performed on 21 patients with varus KOA with MMPRT from May 2020 to December 2021,including 3 males and 18 females,aged from 49 to 75 years old with an average of(63.81±6.56)years old,the courses of disease ranged from 0.5 to 18.0 years with an average of(5.9±4.2)years,and 4 patients with grade Ⅱ,14 patients with grade Ⅲ,and 3 patients with grade Ⅳ according to Kellgren-Lawrence;14 patients with type 1 and 7 patients with type 2 according to MMPRT damage classification.The distance of medi-al meniscusextrusion(MME)and weight-bearing line ratio(WBLR)of lower extremity were compared before and 12 months after operation.Visual analogue scale(V AS),Western Ontarioand and McMaster Universities(WOMAC)osteoarthritis index,and Lysholm knee score were used to evaluate knee pain and functional improvement before operation,1,6 and 12 months after operation,respectively.Results Twenty-one patients were followed up for 12 to 18 months with an average of(13.52±1.72)months.MME distance was improved from(4.99±1.05)mm before operation to(1.87±0.76)mm at 12 months after operation(P<0.05).WBLR was increased from(15.49±7.04)%before operation to(62.71±2.27)%at 12 months after operation(P<0.05).VAS was decreased from(7.00±1.14)before operation to(2.04±0.80),(0.90±0.62)and(0.61±0.50)at 1,6 and 12 months after operation.WOMAC were decreased from preoperative(147.90±9.88)to postoperative(103.43±8.52),(74.00±9.54)and(47.62±9.53)at 1,6 and 12 months,and the difference were statistically significant(P<0.05).Lysholm scores were increased from(46.04±7.34)before oepration to(63.19±8.93),(81.10±6.41)and(89.29±3.04)at 1,6 and 12 months after operation(P<0.05).Conclusion For the treatment of varus KOA with MMPRT,DTT-HTO could reduce medial meniscus pro-trusion distance,improve the ratio of lower limb force line,and effectively reduce knee pain and improve knee joint function.
		                        		
		                        		
		                        		
		                        	
5.Migraineur patent foramen ovale risk prediction model for female migraine patient streaming and clinical decision-making
Xiao-Chun ZHANG ; Jia-Ning FAN ; Li ZHU ; Feng ZHANG ; Da-Wei LIN ; Wan-Ling WANG ; Wen-Zhi PAN ; Da-Xin ZHOU ; Jun-Bo GE
Fudan University Journal of Medical Sciences 2024;51(4):505-514
		                        		
		                        			
		                        			Objective To investigate the clinical characteristics of female migraine patients with patent foramen ovale(PFO)and design a risk prediction model for PFO in female migraine patients(migraineur patients PFO risk prediction model,MPRPM).Methods Female migraine patients who visited Zhongshan Hospital,Fudan University from Jun 1,2019 to Dec 31,2022 were included.Preoperative information and follow-up results after discontinuation of medication were collected.Patients were divided into PFO-positive and PFO-negative groups based on transesophageal echocardiography results.A multivariate Logistic regression model and a random forest model were constructed,and the random forest model was validated multidimensionally.Key features were selected based on the mean decrease accuracy(MDA)to construct MPRPM.Results A total of 305 female patients were included in the study,with 204 patients in the PFO-positive group and 101 patients in the PFO-negative group.Multivariate Logistic regression analysis showed that age at migraine onset,attack frequency,severe impact on life during attacks,exercise-related headaches,menstruation-induced headaches,aura migraines,and a history of cryptogenic stroke were predictive factors for PFO positivity.The random forest model effectively predicted the incidence of PFO in female migraine patients,with an AUC of 0.895(95%CI:0.847-0.943).MPRPM demonstrated a sensitivity of 71.6%and specificity of 91.1%(AUC:0.862,95%CI:0.818-0.906,P<0.001).The optimal cut-off value was 2.5 points.Patients correctly classified by the model showed a higher rate of symptom improvement compared to incorrectly classified patients(94.3%vs.82.0%,P=0.023).Conclusion We identified predictive factors for PFO in migraine patients.MPRPM can provide guidance in the diagnostic process and therapeutic decision-making for female migraine patients,assist in patient triage,and reduce the healthcare burden.
		                        		
		                        		
		                        		
		                        	
6.Analysis of the Current Situation of Basic Research on Acupuncture and Moxibustion and Strategy for Its Development
Xiao-Rong TANG ; Si-Yun CHEN ; Wei-Hua YUAN ; Jian SUN ; Ai-Jun LIU ; Li-Ming LU ; Chun-Zhi TANG ; Neng-Gui XU
Journal of Guangzhou University of Traditional Chinese Medicine 2024;41(10):2727-2733
		                        		
		                        			
		                        			In recent years,the development of acupuncture and moxibustion(shortened as acup-moxibustion)has flourished.With the verification of clinical efficacy of acup-moxibustion,its basic research has gradually drawn the attention of the practitioners accordingly.But how to scientifically perform the basic research of acup-moxibustion and to serve the clinic effectively has become a major problem for the contemporary Chinese medicine practitioners.By analyzing the characteristics of acup-moxibustion-related research projects funded by the National Natural Science Foundation of China,this paper outlined the current status of domestic research of acup-moxibustion,and proposed four suggestions after analyzing the problems and weaknesses of acup-moxibustion basic research in China:①the clinical evidence-based system in the current acup-moxibustion should be further constructed and the basic research should be focused on the area of advantages;② the key problems of acup-moxibustion basic research should be clarified,and the proportion of original researches should be increased;③ the integration of production,teaching and research of acup-moxibustion should be enhanced to adapt to the era of big science;④ the funding system and its polity and structure needed to be reformed.This study will help to increase the discipline ranking of acup-moxibustion,enhance its high-quality development,and promote its internationalization.
		                        		
		                        		
		                        		
		                        	
7.Characteristics and clinical significance of changes in peripheral blood B lymphocyte subsets in patients with chronic hepatitis B
Hai-Yan WANG ; Chun-Mei BAO ; Zhi-Qian FENG ; Jing WANG ; Ya-Qun LI ; Jing LI ; Hong-Min WANG ; Li-Li TANG ; Tao YANG ; Ruo-Nan XU ; Fu-Sheng WANG
Medical Journal of Chinese People's Liberation Army 2024;49(5):511-518
		                        		
		                        			
		                        			Objective To analyze the changes of B lymphocyte(B cells)subsets in peripheral blood of patients with chronic hepatitis B(CHB)and to explore its clinical significance.Methods Peripheral blood samples were collected from 37 treatment-na?ve CHB patients who were admitted to the Fifth Medical Center of PLA General Hospital from July 2022 to October 2022,and peripheral blood samples collected from 18 healthy individuals who have received the hepatitis B vaccine as healthy controls(HC).The study subjects'clinical indexes such as age,HBV DNA viral load,HBsAg quantification,HBeAg semi quantification,ALT,AST,and AST/ALT ratio were collected.The change characteristics of the frequency,phenotypic and functional markers of peripheral blood B lymphocytes and their subsets were compared between CHB and HC.Using multi-color flow cytometry,and the correlation between them and clinical indexes was analyzed.Results Frequency analysis of each subset of B cells showed that compared with HC,the frequency of total B cells,transitional B cells and naive B cells was decreased(P<0.05),while the frequency of mature B cells,memory B cells,atypical memory B cells and activated memory B cells was increased in CHB patients(P<0.01).And there was no significant difference in the frequency of resting memory B cells between the two groups(P>0.05).The results of functional analysis showed that compared with HC,the expression levels of CD79b on total B cells,mature B cells,memory B cells,naive B cells,activated memory B cells,atypical memory B cells and resting memory B cells in CHB patients were increased(P<0.05).The expression level of programmed cell death protein-1(PD-1)on atypical memory B cells in CHB patients was also higher than that in HC group(P<0.05).The results of correlation analysis showed that the frequency of total B cells in CHB patients was slightly negatively correlated with age(r=-0.39,P<0.05),while the expression of programmed death-1(PD-1)on total B cells,mature B cells,transitional B cells,memory B cells and naive B cells were slightly positively correlated with age(r>0.36,P<0.05).Conclusions Chronic HBV infection leads to depletion of the frequency and function of a portion of B cells in the peripheral blood of CHB patients,and age is a potential risk factor for the decline in humoral immune function in CHB patients.
		                        		
		                        		
		                        		
		                        	
8.Promotion mechanism of astragaloside on axon repair and regeneration in experimental autoimmune encephalomyelitis mice
Jian-Chun LIU ; Hong-Zhen ZHANG ; Qing WANG ; Hui-Jie FAN ; Li-Juan SONG ; Zhi CHAI ; Cun-Gen MA
Medical Journal of Chinese People's Liberation Army 2024;49(8):914-921
		                        		
		                        			
		                        			Objective To investigate the effects of astragaloside Ⅳ(AS-Ⅳ)on axon growth inhibitory factor A(Nogo-A)and its downstream pathway protein RHO-associated coiled spiral kinase 2(ROCK2)in experimental autoimmune encephalomyelitis(EAE)mice,and to explore the mechanism by which it promotes axon repair and regeneration.Methods EAE model was induced in C57BL/6 female mice by subcutaneous injection of myelin oligodendrocyte glycoprotein 35-55(MOG35-55).Mice were randomly divided into EAE group and AS-Ⅳ group(n=8 per group).EAE group received intraperitoneal injection of PBS on the 3rd day post-immunization,while AS-Ⅳ group was administered AS-Ⅳ at a dosage of 30mg/(kg.d)once daily,0.2 ml per injection,for 25 consecutive days.On the 28th day post-immunization,the expression levels of growth-associated protein 43(GAP-43),neuronal core antigen(NeuN),microtubule associated protein 2(MAP-2),glial fibroacidic protein(GFAP),and Iba1 in the spinal cord were detected using immunofluorescence assay.Real-time fluorescence quantitative PCR(qRT-PCR)was conducted to detect mRNA expression levels of GAP-43,Nogo-A,and Nogo receptor(NgR)genes.Western blotting was utilized to determine the expression levels of GAP-43,Nogo-A,ROCK2,phosphorylated myosin phosphatase(p-MYPT1),B-lymphoblastoma-2(Bcl-2),and Bcl-2 associated X protein(Bax).Results Compared with EAE group,AS-Ⅳ treatment significantly reduced the positive cell expression rates of Iba1 microglia and GFAP astrocyte in spinal cord(P<0.01 and P<0.001,respectively),while it also increased the positive expression rates of NeuN and MAP-2(P<0.001 and P<0.05,respectively).The treatment also upregulated the expression level of anti-apoptotic factor Bcl-2(P<0.001)and downregulated the expression level of pro-apoptotic factor Bax(P<0.05),leading to an increase in Bcl-2/Bax ratio(P<0.05).Furthermore,AS-Ⅳ enhanced the expression of GAP-43 protein(P<0.05)and decreased the mRNA expression levels of neuroregeneration inhibitor Nogo receptor(NgR)and ROCK2 gene(P<0.001,P<0.05,respectively);as well as decreased the expression levels of Nogo-A,ROCK2 and p-MYPT1 proteins(P<0.05,P<0.001).Conclusion AS-Ⅳ may inhibit the activation of microglia and astrocytes and neuronal apoptosis in EAE mice by inhibiting Nogo-A and downstream pathway ROCK 2,thereby promoting the expression of GAP-43,NeuN and MAP-2,alleviating neuronal damage,and facilitating axon repair and regeneration.
		                        		
		                        		
		                        		
		                        	
9.Effects of hypobaric hypoxia intervention on behavioral and hematological indicators in PTSD rats
Bao-Ying SHEN ; Zhi-Xing WANG ; Bo-Wei LI ; Chun-Qi YANG ; Xin SHEN ; Cheng-Cai LAI ; Yue GAO
Chinese Pharmacological Bulletin 2024;40(7):1231-1239
		                        		
		                        			
		                        			Aim To preliminarily evaluate the effects of hypobaric hypoxia on organism damage in rats with post-traumatic stress disorder(PTSD),with a view to laying a foundation for drug research in plateau PTSD.Methods The rats were randomly divided into four groups,namely,the control(Control)group,the sin-gle-prolonged stress(SPS)group,the hypobaric hy-poxia(HH)group and the single-prolonged stress combined with hypobaric hypoxia(SPS+HH)group.The PTSD model was firstly constructed using the SPS method for rats in the SPS and SPS+HH groups.On the second day,rats in the HH group and SPS+HH group were placed in a low-pressure hypoxia chamber at a simulated altitude of 6000 m for 14 days.General condition,behavior,blood tests,and histomorphology were examined in order to evaluate the damage caused by low pressure hypoxia in PTSD rats.Results The body mass of rats in the SPS+HH group was signifi-cantly reduced;the feces were partly hard and lumpy,and some of them were seen to have high viscosity.Anxiety-like and depression-like behaviors were ob-served in all groups except in the control group,in which hypobaric hypoxia aggravated the behavioral ab-normalities in SPS rats.Rats in both the SPS and SPS+HH groups had coagulation dysfunction and abnor-mally increased blood viscosity,which was significantly abnormal in the SPS+HH group;erythrocytes,hemo-globin,and erythrocyte specific volume in whole blood of rats in the SPS+HH group were significantly in-creased compared with those of rats in the SPS group;and serum TP,LDH and GLU levels were abnormal in rats in the SPS+HH group.Dilated and congested blood vessels were seen in hippocampal tissue,conges-ted central veins were seen in hepatic tissue,and dilat-ed and congested liver sinusoids with mild granuloma-tous degeneration of hepatocytes were seen in rats of the SPS+HH group.Conclusion Hypobaric hypoxia exacerbates depression-like and anxiety-like behaviors in PTSD rats,as well as hematological indices and his-tomorphometric abnormalities in PTSD rats.
		                        		
		                        		
		                        		
		                        	
10.Radix Angelica Sinensis and Radix Astragalus ultrafiltration extract improves radiation-induced pulmonary fibrosis in rats by regulating NLRP3/caspase-1/GSDMD pyroptosis pathway
Chun-Zhen REN ; Jian-Fang YUAN ; Chun-Ling WANG ; Xiao-Dong ZHI ; Qi-Li ZHANG ; Qi-Lin CHEN ; Xin-Fang LYU ; Xiang GAO ; Xue WU ; Xin-Ke ZHAO ; Ying-Dong LI
Chinese Pharmacological Bulletin 2024;40(11):2124-2131
		                        		
		                        			
		                        			Aim To investigate the mechanism of py-roptosis mediated by the NLRP3/caspase-1/GSDMD signaling pathway and the intervention effect of Radix Angelica Sinensis and Radix Astragalus ultrafiltration extract(RAS-RA)in radiation-induced pulmonary fi-brosis.Methods Fifty Wistar rats were randomly di-vided into five groups,with ten rats in each group.Ex-cept for the blank control group,all other groups of rats were anesthetized and received a single dose of 40 Gy X-ray local chest radiation to establish a radiation-in-duced pulmonary fibrosis rat model.After radiation,the rats in the RAS-RA intervention groups were orally administered doses of 0.12,0.24 and 0.48 g·kg-1 once a day for 30 days.The average weight and lung index of the rats were observed after 30 days of contin-uous administration.Hydroxyproline(HYP)content in lung tissue was determined by hydrolysis method.The levels of IL-18 and IL-1 β in serum were detected by ELISA.Lung tissue pathological changes were ob-served by HE and Masson staining.Ultrastructural changes in lung tissue were observed by transmission e-lectron microscopy.The expression levels of NLRP3/caspase-1/GSDMD pyroptosis pathway-related proteins and fibrosis-related proteins in lung tissue were detec-ted by Western blot.Results Compared with the blank group,the HYP content in lung tissue and the levels of IL-18 and IL-1 β in serum significantly in-creased in the model group(P<0.01).HE and Mas-son staining showed inflammatory cell infiltration and collagen fiber deposition.Transmission electron mi-croscopy revealed increased damaged mitochondria,disordered arrangement,irregular morphology,shallow matrix,outer membrane rupture,mostly fractured and shortened cristae,mild expansion,increased electron density of individual mitochondrial matrix,mild sparse structure of lamellar bodies,partial disorder,unclear organelles,and characteristic changes of pyroptosis.Western blot analysis showed increased expression of caspase-1,GSDMD,NLRP3,CoL-Ⅰ,α-SMA,and CoL-Ⅲ proteins(P<0.01).Compared with the model group,the RAS-RA intervention group showed signifi-cant improvement in body mass index and lung index of rats,decreased levels of IL-18 and IL-1 β inflammatory factors(P<0.01),improved mitochondrial structure,reduced degree of fibrosis,and decreased expression of caspase-1,GSDMD,NLRP3,COL-Ⅰ,COL-Ⅲ,and α-SMA proteins in lung tissue(P<0.01).Conclusion RAS-RA has an inhibitory effect on radiation-in-duced pulmonary fibrosis,and its mechanism may be related to the inhibition of pyroptosis through the regu-lation of the NLRP3/caspase-1/GSDMD signaling pathway.
		                        		
		                        		
		                        		
		                        	
            
Result Analysis
Print
Save
E-mail