1.Preparation of Triptolide-Chuanxiong Rhizoma Extract Ethanol Transfersomes and Analysis on Its in Vitro Anti-inflammatory Mechanism
Ling TAO ; Zhiyan WAN ; Yidan LIU ; Zhe LI ; Zhenzhong ZANG ; Weifeng ZHU ; Yongmei GUAN
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(10):210-218
ObjectiveTo prepare triptolide-Chuanxiong Rhizoma extract ethanol transfersomes(TP-CX@TESs), conduct its quality evaluation, and investigate its in vitro anti-inflammatory efficacy and the underlying mechanisms. MethodsTP-CX@TESs was prepared via the ultrasonic injection method. With encapsulation efficiency and particle size as evaluation indicators, Box-Behnken design-response surface methodology(BBD-RSM) was employed to optimize the formulation process. The TP-CX@TESs prepared under the optimal process was characterized and evaluated for in vitro transdermal performance. A lipopolysaccharide(LPS)-induced RAW264.7 cell inflammation model was established. After 24 h of drug intervention, the levels of inflammatory factors such as nitric oxide(NO), interleukin-6(IL-6), and tumor necrosis factor-α(TNF-α) in the cell supernatant were detected. Western blot was used to determine the protein expression levels of Janus kinase 2(JAK2), signal transducer and activator of transcription 3(STAT3), and α7 nicotinic acetylcholine receptor(α7nAChR), and real-time fluorescence quantitative polymerase chain reaction(Real-time PCR) was applied to measure the mRNA expression levels of JAK2, STAT3, the encoding gene of α7nAChR(CHRNA7), and nuclear transcription factor-κB(NF-κB). ResultsResults of BBD-RSM showed that the optimal formulation for preparing TP-CX@TESs was as follows:egg yolk lecithin content of 2.3%, ethanol volume fraction of 30%, and ratio of polysorbate-80 to egg yolk lecithin of 2∶5. Microscopic characterization revealed that TP-CX@TESs exhibited a spherical-like structure with a particle size of (105.60±3.85) nm, a polydispersity index of 0.19±0.03, and a Zeta potential of (-15.89±0.98) mV. The encapsulation efficiencies of triptolide, ferulic acid, and ligustilide were (76.88±4.40)%, (78.84±4.40)%, and (65.88±0.06)%, respectively. Both in vitro release and transdermal penetration of triptolide, ferulic acid, and ligustilide in TP-CX@TESs all followed the first-order kinetic model, showing a certain sustained-release property. Experimental results in RAW264.7 cells indicated that TP-CX@TESs significantly inhibited the release of NO, TNF-α, and IL-6(P<0.01), remarkably upregulated the protein expression levels of STAT3 and α7nAChR(P<0.01), increased the mRNA expression level of CHRNA7, and significantly downregulated the mRNA expression level of NF-κB(P<0.05, P<0.01). ConclusionThe optimized formulation process of TP-CX@TESs is simple and feasible, along with favorable in vitro release property, good transdermal permeability, and excellent in vitro anti-inflammatory activity, the mechanism is related to the inhibition of NF-κB.
2.Preparation of Triptolide-Chuanxiong Rhizoma Extract Ethanol Transfersomes and Analysis on Its in Vitro Anti-inflammatory Mechanism
Ling TAO ; Zhiyan WAN ; Yidan LIU ; Zhe LI ; Zhenzhong ZANG ; Weifeng ZHU ; Yongmei GUAN
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(10):210-218
ObjectiveTo prepare triptolide-Chuanxiong Rhizoma extract ethanol transfersomes(TP-CX@TESs), conduct its quality evaluation, and investigate its in vitro anti-inflammatory efficacy and the underlying mechanisms. MethodsTP-CX@TESs was prepared via the ultrasonic injection method. With encapsulation efficiency and particle size as evaluation indicators, Box-Behnken design-response surface methodology(BBD-RSM) was employed to optimize the formulation process. The TP-CX@TESs prepared under the optimal process was characterized and evaluated for in vitro transdermal performance. A lipopolysaccharide(LPS)-induced RAW264.7 cell inflammation model was established. After 24 h of drug intervention, the levels of inflammatory factors such as nitric oxide(NO), interleukin-6(IL-6), and tumor necrosis factor-α(TNF-α) in the cell supernatant were detected. Western blot was used to determine the protein expression levels of Janus kinase 2(JAK2), signal transducer and activator of transcription 3(STAT3), and α7 nicotinic acetylcholine receptor(α7nAChR), and real-time fluorescence quantitative polymerase chain reaction(Real-time PCR) was applied to measure the mRNA expression levels of JAK2, STAT3, the encoding gene of α7nAChR(CHRNA7), and nuclear transcription factor-κB(NF-κB). ResultsResults of BBD-RSM showed that the optimal formulation for preparing TP-CX@TESs was as follows:egg yolk lecithin content of 2.3%, ethanol volume fraction of 30%, and ratio of polysorbate-80 to egg yolk lecithin of 2∶5. Microscopic characterization revealed that TP-CX@TESs exhibited a spherical-like structure with a particle size of (105.60±3.85) nm, a polydispersity index of 0.19±0.03, and a Zeta potential of (-15.89±0.98) mV. The encapsulation efficiencies of triptolide, ferulic acid, and ligustilide were (76.88±4.40)%, (78.84±4.40)%, and (65.88±0.06)%, respectively. Both in vitro release and transdermal penetration of triptolide, ferulic acid, and ligustilide in TP-CX@TESs all followed the first-order kinetic model, showing a certain sustained-release property. Experimental results in RAW264.7 cells indicated that TP-CX@TESs significantly inhibited the release of NO, TNF-α, and IL-6(P<0.01), remarkably upregulated the protein expression levels of STAT3 and α7nAChR(P<0.01), increased the mRNA expression level of CHRNA7, and significantly downregulated the mRNA expression level of NF-κB(P<0.05, P<0.01). ConclusionThe optimized formulation process of TP-CX@TESs is simple and feasible, along with favorable in vitro release property, good transdermal permeability, and excellent in vitro anti-inflammatory activity, the mechanism is related to the inhibition of NF-κB.
3.The mechanism of nicotinamide combined with amphotericin B against Candida albicans based on metabolomics technology
Lizhi WAN ; Jinghan WANG ; Chunrong WU ; Ling LI
Journal of Pharmaceutical Practice and Service 2026;44(1):20-25
Objective To investigate the potential mechanism of nicotinamide combined with amphotericin B against Candida albicans based on metabolomics. Methods The intracellular metabolites of C. albicans intervened by different drugs including NAM, AmB, and their combination with a proper concentration were analyzed by gas chromatography-mass spectrometry. The differential metabolites were screened by multivariate statistical analysis and identified by searching the NIST database. Results Compared with the control group, the NAM intervention group was hardly separated from it, while the AmB group and NAM+AmB group showed a clear trend of separation. Under the intervention of AmB, 23 metabolites significantly changed compared with the control group, and 28 metabolites remarkably changed after NAM+AmB intervention, including amino acids, organic acids, sugars and other components. Conclusion NAM, as an endogenous metabolite of C. albicans, combined with AmB could enhance the effects of AmB in the original metabolic pathway and changed it to a certain extent. It was speculated that AmB combined with NAM may pose more antifungal effect on Candida albicans by regulating the tricarboxylic acid cycle,interfering with amino acid metabolism and influencing polyamine synthesis.
4.Real-world efficacy and safety of azvudine in hospitalized older patients with COVID-19 during the omicron wave in China: A retrospective cohort study.
Yuanchao ZHU ; Fei ZHAO ; Yubing ZHU ; Xingang LI ; Deshi DONG ; Bolin ZHU ; Jianchun LI ; Xin HU ; Zinan ZHAO ; Wenfeng XU ; Yang JV ; Dandan WANG ; Yingming ZHENG ; Yiwen DONG ; Lu LI ; Shilei YANG ; Zhiyuan TENG ; Ling LU ; Jingwei ZHU ; Linzhe DU ; Yunxin LIU ; Lechuan JIA ; Qiujv ZHANG ; Hui MA ; Ana ZHAO ; Hongliu JIANG ; Xin XU ; Jinli WANG ; Xuping QIAN ; Wei ZHANG ; Tingting ZHENG ; Chunxia YANG ; Xuguang CHEN ; Kun LIU ; Huanhuan JIANG ; Dongxiang QU ; Jia SONG ; Hua CHENG ; Wenfang SUN ; Hanqiu ZHAN ; Xiao LI ; Yafeng WANG ; Aixia WANG ; Li LIU ; Lihua YANG ; Nan ZHANG ; Shumin CHEN ; Jingjing MA ; Wei LIU ; Xiaoxiang DU ; Meiqin ZHENG ; Liyan WAN ; Guangqing DU ; Hangmei LIU ; Pengfei JIN
Acta Pharmaceutica Sinica B 2025;15(1):123-132
Debates persist regarding the efficacy and safety of azvudine, particularly its real-world outcomes. This study involved patients aged ≥60 years who were admitted to 25 hospitals in mainland China with confirmed SARS-CoV-2 infection between December 1, 2022, and February 28, 2023. Efficacy outcomes were all-cause mortality during hospitalization, the proportion of patients discharged with recovery, time to nucleic acid-negative conversion (T NANC), time to symptom improvement (T SI), and time of hospital stay (T HS). Safety was also assessed. Among the 5884 participants identified, 1999 received azvudine, and 1999 matched controls were included after exclusion and propensity score matching. Azvudine recipients exhibited lower all-cause mortality compared with controls in the overall population (13.3% vs. 17.1%, RR, 0.78; 95% CI, 0.67-0.90; P = 0.001) and in the severe subgroup (25.7% vs. 33.7%; RR, 0.76; 95% CI, 0.66-0.88; P < 0.001). A higher proportion of patients discharged with recovery, and a shorter T NANC were associated with azvudine recipients, especially in the severe subgroup. The incidence of adverse events in azvudine recipients was comparable to that in the control group (2.3% vs. 1.7%, P = 0.170). In conclusion, azvudine showed efficacy and safety in older patients hospitalized with COVID-19 during the SARS-CoV-2 omicron wave in China.
5.Prediction of testicular histology in azoospermia patients through deep learning-enabled two-dimensional grayscale ultrasound.
Jia-Ying HU ; Zhen-Zhe LIN ; Li DING ; Zhi-Xing ZHANG ; Wan-Ling HUANG ; Sha-Sha HUANG ; Bin LI ; Xiao-Yan XIE ; Ming-De LU ; Chun-Hua DENG ; Hao-Tian LIN ; Yong GAO ; Zhu WANG
Asian Journal of Andrology 2025;27(2):254-260
Testicular histology based on testicular biopsy is an important factor for determining appropriate testicular sperm extraction surgery and predicting sperm retrieval outcomes in patients with azoospermia. Therefore, we developed a deep learning (DL) model to establish the associations between testicular grayscale ultrasound images and testicular histology. We retrospectively included two-dimensional testicular grayscale ultrasound from patients with azoospermia (353 men with 4357 images between July 2017 and December 2021 in The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China) to develop a DL model. We obtained testicular histology during conventional testicular sperm extraction. Our DL model was trained based on ultrasound images or fusion data (ultrasound images fused with the corresponding testicular volume) to distinguish spermatozoa presence in pathology (SPP) and spermatozoa absence in pathology (SAP) and to classify maturation arrest (MA) and Sertoli cell-only syndrome (SCOS) in patients with SAP. Areas under the receiver operating characteristic curve (AUCs), accuracy, sensitivity, and specificity were used to analyze model performance. DL based on images achieved an AUC of 0.922 (95% confidence interval [CI]: 0.908-0.935), a sensitivity of 80.9%, a specificity of 84.6%, and an accuracy of 83.5% in predicting SPP (including normal spermatogenesis and hypospermatogenesis) and SAP (including MA and SCOS). In the identification of SCOS and MA, DL on fusion data yielded better diagnostic performance with an AUC of 0.979 (95% CI: 0.969-0.989), a sensitivity of 89.7%, a specificity of 97.1%, and an accuracy of 92.1%. Our study provides a noninvasive method to predict testicular histology for patients with azoospermia, which would avoid unnecessary testicular biopsy.
Humans
;
Male
;
Azoospermia/diagnostic imaging*
;
Deep Learning
;
Testis/pathology*
;
Retrospective Studies
;
Adult
;
Ultrasonography/methods*
;
Sperm Retrieval
;
Sertoli Cell-Only Syndrome/diagnostic imaging*
6.Molecular targeted therapy for progressive low-grade gliomas in children.
Yan-Ling SUN ; Miao LI ; Jing-Jing LIU ; Wen-Chao GAO ; Yue-Fang WU ; Lu-Lu WAN ; Si-Qi REN ; Shu-Xu DU ; Wan-Shui WU ; Li-Ming SUN
Chinese Journal of Contemporary Pediatrics 2025;27(6):682-689
OBJECTIVES:
To evaluate the efficacy of molecular targeted agents in children with progressive pediatric low-grade gliomas (pLGG).
METHODS:
A retrospective analysis was conducted on pLGG patients treated with oral targeted therapies at the Department of Pediatrics, Beijing Shijitan Hospital, Capital Medical University, from July 2021. Treatment responses and safety profiles were assessed.
RESULTS:
Among the 20 enrolled patients, the trametinib group (n=12, including 11 cases with BRAF fusions and 1 case with BRAF V600E mutation) demonstrated 4 partial responses (33%) and 2 minor responses (17%), with a median time to response of 3.0 months. In the vemurafenib group (n=6, all with BRAF V600E mutation), 5 patients achieved partial responses (83%), showing a median time to response of 1.0 month. Comparative analysis revealed no statistically significant difference in progression-free survival rates between the two treatment groups (P>0.05). The median duration of clinical benefit (defined as partial response + minor response + stable disease) was 11.0 months for vemurafenib and 18.0 months for trametinib. Two additional cases, one with ATM mutation treated with olaparib for 24 months and one with NF1 mutation receiving everolimus for 21 months, discontinued treatment due to sustained disease stability. No severe adverse events were observed in any treatment group.
CONCLUSIONS
Molecular targeted therapy demonstrates clinical efficacy with favorable tolerability in pLGG. Vemurafenib achieves high response rates and induces early tumor shrinkage in patients with BRAF V600E mutations, supporting its utility as a first-line therapy.
Humans
;
Glioma/genetics*
;
Male
;
Female
;
Child
;
Child, Preschool
;
Retrospective Studies
;
Brain Neoplasms/genetics*
;
Molecular Targeted Therapy/adverse effects*
;
Adolescent
;
Infant
;
Proto-Oncogene Proteins B-raf/genetics*
;
Pyrimidinones/therapeutic use*
;
Mutation
7.A Study of Flow Sorting Lymphocyte Subsets to Detect Epstein-Barr Virus Reactivation in Patients with Hematological Malignancies.
Hui-Ying LI ; Shen-Hao LIU ; Fang-Tong LIU ; Kai-Wen TAN ; Zi-Hao WANG ; Han-Yu CAO ; Si-Man HUANG ; Chao-Ling WAN ; Hai-Ping DAI ; Sheng-Li XUE ; Lian BAI
Journal of Experimental Hematology 2025;33(5):1468-1475
OBJECTIVE:
To analyze the Epstein-Barr virus (EBV) load in different lymphocyte subsets, as well as clinical characteristics and outcomes in patients with hematologic malignancies experiencing EBV reactivation.
METHODS:
Peripheral blood samples from patients were collected. B, T, and NK cells were isolated sorting with magnetic beads by flow cytometry. The EBV load in each subset was quantitated by real-time quantitative polymerase chain reaction (RT-qPCR). Clinical data were colleted from electronic medical records. Survival status was followed up through outpatient visits and telephone calls. Statistical analyses were performed using SPSS 25.0.
RESULTS:
A total of 39 patients with hematologic malignancies were included, among whom 35 patients had undergone allogeneic hematopoietic stem cell transplantation (allo-HSCT). The median time to EBV reactivation was 4.8 months (range: 1.7-57.1 months) after allo-HSCT. EBV was detected in B, T, and NK cells in 20 patients, in B and T cells in 11 patients, and only in B cells in 4 patients. In the 35 patients, the median EBV load in B cells was 2.19×104 copies/ml, significantly higher than that in T cells (4.00×103 copies/ml, P <0.01) and NK cells (2.85×102 copies/ml, P <0.01). Rituximab (RTX) was administered for 32 patients, resulting in EBV negativity in 32 patients with a median time of 8 days (range: 2-39 days). Post-treatment analysis of 13 patients showed EBV were all negative in B, T, and NK cells. In the four non-transplant patients, the median time to EBV reactivation was 35 days (range: 1-328 days) after diagnosis of the primary disease. EBV was detected in one or two subsets of B, T, or NK cells, but not simultaneously in all three subsets. These patients received a combination chemotherapy targeting at the primary disease, with 3 patients achieving EBV negativity, and the median time to be negative was 40 days (range: 13-75 days).
CONCLUSION
In hematologic malignancy patients after allo-HSCT, EBV reactivation commonly involves B, T, and NK cells, with a significantly higher viral load in B cells compared to T and NK cells. Rituximab is effective for EBV clearance. In non-transplant patients, EBV reactivation is restricted to one or two lymphocyte subsets, and clearance is slower, highlighting the need for prompt anti-tumor therapy.
Humans
;
Hematologic Neoplasms/virology*
;
Herpesvirus 4, Human/physiology*
;
Epstein-Barr Virus Infections
;
Hematopoietic Stem Cell Transplantation
;
Virus Activation
;
Lymphocyte Subsets/virology*
;
Flow Cytometry
;
Killer Cells, Natural/virology*
;
Male
;
Female
;
B-Lymphocytes/virology*
;
Viral Load
;
Adult
;
T-Lymphocytes/virology*
;
Middle Aged
8.Antithrombotic effect in zebrafish of a fibrinolytic protein EPF3 from Dilong (Pheretima vulgaris Chen) and its transport mechanism in Caco-2 monolayer through cell bypass pathway.
Wan-Ling ZHONG ; Jian-Qiong YANG ; Hai LIU ; Ya-Li WU ; Hui-Juan SHEN ; Peng-Yue LI ; Shou-Ying DU
Journal of Integrative Medicine 2025;23(4):415-428
OBJECTIVE:
EPF3 is a fibrinolysin monomer isolated and purified from Pheretima vulgaris Chen, an earthworm used in traditional Chinese medicine as Dilong for treating blood stasis syndrome. Its composition, anticoagulant and fibrinolytic activities, and relevant mechanisms have been confirmed through in vitro experiments. However, whether it has antithrombotic effects in vivo and can be absorbed by the gastrointestinal tract is unknown. This study evaluates the antithrombotic effect in zebrafish and investigates the gastrointestinal stability and intestinal absorption mechanism of this protein in vitro.
METHODS:
The antithrombotic effect of EPF3 in vivo was verified using the zebrafish thrombus model induced by arachidonic acid and FeCl3. Then, the protein bands of EPF3 incubated with simulated gastric fluid (SGF), simulated intestinal fluid (SIF), and homogenate of Caco-2 cells (HC2C) were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis to evaluate its gastrointestinal stability. Finally, the transport behavior and absorption mechanism of EPF3 were studied using Caco-2 cell monolayer.
RESULTS:
EPF3 could significantly enhance the returned blood volume and blood flow velocity in zebrafish with platelet aggregation thrombus induced by arachidonic acid. It could also prolong the formation time of tail artery thrombus and increase the blood flow velocity in zebrafish with vessel injury thrombus induced by FeCl3. EPF3 was stable in SIF and HC2C and unstable in SGF. The permeability of EPF3 in Caco-2 monolayer was time-dependent and concentration-dependent. The efflux ratio was less than 1.2 during transport, and the transport behavior was not affected by inhibitors. EPF3 could reversibly reduce the expression of tight junction-related proteins, including zonula occludens-1, occludin, and claudin-1 in Caco-2 cells.
CONCLUSION
EPF3 could play a thrombolytic and antithrombotic role in zebrafish. It could be transported and absorbed into the intestine through cellular bypass pathway by opening the intestinal epithelium tight junction. This study provides a scientific explanation for the antithrombotic effect of earthworm and provides a basis for the feasibility of subsequent development of EPF3 as an antithrombotic enteric-soluble preparation. Please cite this article as: Zhong WL, Yang JQ, Liu H, Wu YL, Shen HJ, Li PY, Du SY. Antithrombotic effect in zebrafish of a fibrinolytic protein EPF3 from Dilong (Pheretima vulgaris Chen) and its transport mechanism in Caco-2 monolayer through cell bypass pathway. J Integr Med. 2025; 23(4): 415-428.
Animals
;
Zebrafish
;
Humans
;
Caco-2 Cells
;
Fibrinolytic Agents/pharmacology*
;
Thrombosis/drug therapy*
;
Intestinal Absorption
9.Validation and Reproducibility of an Iodine-specific Food Frequency Questionnaire for Evaluating Dietary Iodine Intake in the Elderly Population of Gansu Province, China.
Qi JIN ; Tao WANG ; Mei Na JI ; Ji Zun WANG ; Xing MA ; Xin Yi WANG ; Jia Qi WANG ; He Xi ZHANG ; Yan Ling WANG ; Wen Xing GUO ; Wan Qi ZHANG
Biomedical and Environmental Sciences 2025;38(9):1168-1172
10.Mechanistic of Yueju Wan volatile oil in inhibiting inflammation for antidepressant effects by regulating AGE/PI3K/Akt pathway.
Tan-Lu CHU ; Ze-Jun GUO ; Wei ZHANG ; Ling-Feng WANG ; Shu-Rui LYU ; Wan-Yu GUO ; Xiao-Ming ZHONG ; Feng-Mei QIU ; Zhen HUANG
China Journal of Chinese Materia Medica 2025;50(11):3147-3158
The antidepressant activity and molecular mechanisms of Yueju Wan volatile oil were investigated. The Yueju Wan volatile oil was extracted by using supercritical CO_2. Gas chromatography-mass spectrometry(GC-MS) combined with network pharmacology identified 28 chemical constituents in Yueju Wan volatile oil, primarily terpenes and lactones. A total of 123 overlapping targets were associated with depression, including core targets of interleukin-1β(IL-1β), signal transducer and activator of transcription 3(STAT3), and caspase-3(CASP3). These targets were mainly involved in the prolactin, advanced glycation end products/receptor(AGE/RAGE), and phosphoinositide 3-kinase/protein kinase B(PI3K/Akt) signaling pathways. A reserpine-induced depression mouse model was established to evaluate the therapeutic effects and mechanisms of Yueju Wan volatile oil. The effects of Yueju Wan volatile oil on depression-like behavior in mice were evaluated by analyzing body mass, body temperature index, tail suspension immobility time, forced swimming immobility time, and sucrose preference. Hematoxylin-eosin(HE) staining revealed neuronal protection of Yueju Wan volatile oil in the brain of mice. Enzyme-linked immunosorbent assay(ELISA) and Western blot were employed to detect the protein expression of AGEs, IL-1β, phosphorylated PI3K(p-PI3K), Akt, phosphorylated Akt(p-Akt), nuclear factor κB(NF-κB), and brain-derived neurotrophic factor(BDNF). Behavioral evaluation showed that Yueju Wan volatile oil could effectively control the decline of body mass and body temperature of depressed mice, reduce tail suspension and swimming immobility time, and enhance their preference for sucrose. Histopathological examination showed that Yueju Wan volatile oil could alleviate the neuronal damage in CA1 and dentate gyrus(DG) of the hippocampus of mice. ELISA and Western blot results showed that Yueju Wan volatile oil could significantly increase the protein expression levels of PI3K, Akt, and BDNF and significantly decrease the protein expression levels of AGEs, IL-1β, p-PI3K, p-Akt, and NF-κB in the hippocampus of mice. Furthermore, the p-PI3K/PI3K and p-Akt/Akt ratios were significantly decreased at medium and high doses. These findings suggest that the aromatherapy of Yueju Wan volatile oil can significantly improve reserpine-induced depression-like behavior in mice, which may be related to reducing the expression of neuronal membrane protein AGEs, reducing the phosphorylation levels of PI3K and Akt, inhibiting NF-κB entry into the nucleus, and alleviating the release of pro-inflammatory factors and nerve injury.
Animals
;
Antidepressive Agents/chemistry*
;
Mice
;
Proto-Oncogene Proteins c-akt/immunology*
;
Phosphatidylinositol 3-Kinases/immunology*
;
Oils, Volatile/chemistry*
;
Male
;
Drugs, Chinese Herbal/chemistry*
;
Signal Transduction/drug effects*
;
Depression/metabolism*
;
Glycation End Products, Advanced/immunology*
;
Humans

Result Analysis
Print
Save
E-mail