1.Effect and mechanism of ertugliflozin on pharmacokinetic of sorafenib and donafenib in rats
Yanru DENG ; Zhi WANG ; Gexi CAO ; Bin YAN ; Ying LI ; Zhanjun DONG
China Pharmacy 2025;36(7):826-831
OBJECTIVE To investigate the effects of ertugliflozin on pharmacokinetic of sorafenib and donafenib in rats and explore the mechanism. METHODS Twenty-four male SD rats were randomly divided into four groups, with 6 rats in each group. Groups A and B were respectively gavaged with 0.5% sodium carboxymethyl cellulose solution and ertugliflozin (1.5 mg/kg) for 7 consecutive days, and both were given sorafenib (100 mg/kg) on the 7th day. Groups C and D were administered intragastrically in the same way as those in Groups A and B, respectively, for the first 7 days; after the drug administration on the 7th day, all rats in Groups C and D were further gavaged with donafenib (40 mg/kg). Blood samples were collected at different time points before and after administration of sorafenib or donafenib, the concentrations of sorafenib in plasma of rats in groups A and B and donafenib in groups C and D were determined by UPLC-MS/MS method. The pharmacokinetic parameters were calculated by DAS 2.1.1 software. Six additional rats were randomly divided into blank control group and ertugliflozin group, with three rats in each group. Blank control group was given 0.5% sodium carboxymethyl cellulose intragastrically, while rats in ertugliflozin group were given ertugliflozin (1.5 mg/kg) once a day for 7 consecutive days. After the last administration, the mRNA expression levels of uridine diphosphate glucuronosyl transferase 1A7 (UGT1A7), breast cancer resistance protein (BCRP), and P-glycoprotein (P-gp) in the liver and small intestine tissues of the rats were detected. RESULTS Compared with group A, the AUC0-t, AUC0-∞, cmax, tmax, MRT0-t and MRT0-∞ of sorafenib in group B were decreased significantly, while CL and V were increased significantly. Compared with group C, the AUC0-t, AUC0-∞ , tmax, cmax and MRT0-t of Δ donafenib in group D were decreased significantly, while V and CL were increased significantly (P<0.05). mRNA expression of UGT1A7, P-gp and BCRP in the liver tissue and small intestine of rats were not significantly affected after intragastric administration of ertugliflozin for 7 consecutive days. CONCLUSIONS Ertugliflozin can affect the pharmacokinetics of sorafenib and donafenib in rats and decrease the plasma exposure of them significantly. However, its mechanism of action may not be through the regulation of related metabolic enzymes and transporters. When using drugs in combination clinically, one should be vigilant about the potential for disease progression due to poor therapeutic effects.
2.Impact of anticentromere antibody on the clinical features and prognosis of patients with primary biliary cholangitis
Shengzhu HE ; Guiqin ZHOU ; Kexin QIAO ; Yaxing LIU ; Bin LI ; Ying FENG ; Xianbo WANG
Journal of Clinical Hepatology 2025;41(5):872-877
ObjectiveTo investigate the impact of anticentromere antibody (ACA) on the clinical features and prognosis of patients with primary biliary cholangitis (PBC) by comparing clinical classification, ursodeoxycholic acid (UDCA) response, GLOBE score, and UK-PBC score between ACA-positive PBC patients and ACA-negative PBC patients. MethodsA total of 749 patients who were admitted to Beijing Ditan Hospital, Capital Medical University, from August 2013 to December 2022 and were diagnosed with PBC were enrolled and divided into ACA-positive group with 147 patients and ACA-negative group with 602 patients. According to their conditions on admission, the two groups were compared in terms of the distribution of clinical types, i.e., chronic progression-type PBC, portal hypertension-type PBC, and standard jaundice/liver failure-type PBC. There were 261 patients with complete data after 1-year follow-up, among whom there were 53 patients with positive ACA and 208 with negative ACA. A statistical analysis was performed, and propensity score matching was performed based on sex and age at a ratio of 1∶2. The two groups were compared in terms of 1-year UDCA response rate, GLOBE score, and UK-PBC score before and after matching. The independent-samples t test or the Mann-Whitney U test was used for comparison of continuous data between two groups, and the chi-square test was used for comparison of categorical data between two groups. ResultsCompared with the ACA-negative group, the ACA-positive group had a significantly higher age (61.28±10.35 years vs 56.74±12.17 years, t=4.164, P<0.001), a significantly higher proportion of female patients (93.9% vs 77.6%, χ2=20.221, P<0.001), a significantly higher proportion of patients with portal hypertension (48.3% vs 27.6%, χ2=23.289, P<0.001), and a significantly lower proportion of patients with jaundice/liver failure (24.5% vs 38.5%, χ2=10.205, P<0.001). After 1-year follow-up, for the 261 PBC patients with complete data, there was no significant difference in UDCA response rate before propensity score matching between the ACA-positive group and the ACA-negative group (41.5% vs 41.8%, P>0.05), and there was a significant difference in the proportion of patients with a GLOBE score of >0.3 between the ACA-positive group and the ACA-negative group (92.5% vs 80.3%, χ2=3.935, P=0.047). There were 53 patients in the ACA-positive group and 106 patients in the ACA-negative group after propensity score matching, and there were no significant differences between the two groups in UDCA response rate, GLOBE score, and UK-PBC score (all P>0.05). ConclusionACA-positive patients tend to have an older age, with a higher proportion of female patients or patients with portal hypertension, while there is a relatively low proportion of patients with jaundice/liver failure. Positive ACA has no significant impact on UDCA response rate, GLOBE score, and UK-PBC score.
3.Clinical efficacy comparison of different acupuncture frequencies for pain of temporomandibular disorders: a randomized controlled trial.
Shuting LI ; Yuanbo FU ; Lu LIU ; Woyu WANG ; Ying LIN ; Bin LI
Chinese Acupuncture & Moxibustion 2025;45(4):453-459
OBJECTIVE:
To explore the efficacy differences among different acupuncture frequencies for pain of temporomandibular disorders (TMD).
METHODS:
A total of 42 patients with TMD pain were randomly divided into a low-frequency group, a medium-frequency group, and a high-frequency group, with 14 patients in each group. All groups received acupuncture treatment at bilateral Hegu (LI4) and Yanglingquan (GB34), as well as ipsilateral Tinggong (SI19), Jiache (ST6), and Xiaguan (ST7), with each session lasting 30 minutes. The low-frequency group received acupuncture once per week, the medium-frequency group received acupuncture twice per week, and the high-frequency group received acupuncture three times per week, for a total duration of four weeks. The graded chronic pain scale (GCPS) score, visual analogue scale (VAS) score, jaw functional limitation scale-20 (JFLS-20) score, and pressure pain threshold (PPT) were assessed in the three groups before and after treatment, as well as at the four-week follow-up after treatment completion.
RESULTS:
Compared before treatment, GCPS and JFLS-20 scores were significantly decreased in all the groups after treatment (P<0.05), and VAS scores were significantly decreased in the high-frequency and medium-frequency groups (P<0.05), PPT values at different measurement sites were increased significantly in the high-frequency group (P<0.05). After treatment, GCPS, JFLS-20, and VAS scores in the high-frequency group were lower than those in the medium-frequency and low-frequency groups (P<0.05), while some PPT values were higher than the other two groups (P<0.05). At follow-up, GCPS, JFLS-20, and VAS scores remained significantly lower in all the groups compared to baseline (P<0.05), PPT values were increased significantly in the high-frequency and medium-frequency groups (P<0.05), with the high-frequency group showing lower GCPS, JFLS-20, and VAS scores and higher PPT values compared to the other two groups (P<0.05).
CONCLUSION
Acupuncture three times per week is more effective in reducing TMD pain intensity compared to once or twice per week, and can also alleviate some mandibular functional impairments. The therapeutic effects persist for at least four weeks after treatment completion.
Humans
;
Male
;
Female
;
Adult
;
Acupuncture Therapy/methods*
;
Temporomandibular Joint Disorders/physiopathology*
;
Middle Aged
;
Young Adult
;
Treatment Outcome
;
Acupuncture Points
;
Pain Management
;
Adolescent
;
Pain Measurement
4.Development status and problems of traditional Chinese medicine seed industry and suggestions for it.
Bao-Juan XUE ; Ying SUN ; Yang ZHAO ; Jun-Shu GE ; Yi WANG ; Zhe-Yuan LIU ; Jiang-Bin LI
China Journal of Chinese Materia Medica 2025;50(4):1132-1136
The inheritance, innovation, and development of traditional Chinese medicine(TCM) need to be based on Chinese medicinal materials. The TCM seed industry is the source of TCM production, which is related to the stable supply and quality safety of TCM. This paper summarizes the basic situation of the TCM seed industry and introduces relevant policies and regulations to TCM seeds in the seed industry and the TCM field. At present, the Management Measures of TCM Seeds and Seedlings has not yet promulgated, and TCM seeds are classified as non-major crops in the category of crops for management. This paper also describes the current situation of TCM seed and seedling system construction, which is in the development stage, from six aspects, including the construction of TCM seed industry technical support system; the establishment of TCM seed standard; the construction of germplasm resource preservation system; TCM seed testing, variety registration, and variety protection; production and management of TCM seeds; TCM seed supervision. According to the development status of the TCM seed industry, four problems are put forward, including imperfect systems and standards relevant to TCM seeds, insufficient supervision and law enforcement regarding TCM seeds, insufficient policy measures and capital investment to promote the development of the industry, and the industry's falling into a low-level cycle.Accordingly, four suggestions are provided, including improving laws, regulations, and policies, perfecting standards and norms,strengthening supervision and law enforcement, and promoting support system construction, in order to boost the high-quality development of the TCM seed industry.
Seeds/chemistry*
;
Medicine, Chinese Traditional
;
Drugs, Chinese Herbal/standards*
;
Plants, Medicinal/chemistry*
5."Component-effect" correlations in traditional Chinese medicine from holistic view: taking discovery of gintonin from ginseng as an example.
Xin-Ming YU ; Chen-Yu YU ; Hua-Ying WANG ; Wei-Sheng YUE ; Zhu-Bin ZHANG ; Wei WU ; Xiao-Bin JIA ; Bing YANG ; Liang FENG
China Journal of Chinese Materia Medica 2025;50(7):2001-2012
The holistic view is the key in the study of traditional Chinese medicine(TCM). The component structure theory is based on the holistic view to investigate the correlation between material basis and efficiency, which enriches the holistic "component-effect" research of TCM. Gintonin is a newly isolated non-saponin component of ginseng. Compared to ginsenosides, gintonin has many different pharmacological activities, and it provides new knowledge for the holistic research of ginseng. Thus, taking the discovery of gintonin from ginseng as an example, this paper explored the linkage between ginsenosides and gintonin from the perspective of "component-effect" correlations and systematically sorted out the similarities and differences between them in terms of structural characteristics, modes of action, and pharmacological activities. Starting from the collaborative interaction of TCM compounds, the study discussed the application and value of the holistic view in TCM "component-effect" research in the light of the component structure theory to provide new thoughts for the development of modern TCM research.
Panax/chemistry*
;
Drugs, Chinese Herbal/pharmacology*
;
Medicine, Chinese Traditional
;
Humans
;
Ginsenosides/pharmacology*
;
Animals
6.Pharmacokinetics of Jinlingzi San and its single medicines in rats by LC-MS/MS.
Nan HU ; Yan-Bin MENG ; Si-Yu SHAN ; Shuang-Shuang ZHENG ; Ying-Han WANG ; Lan WANG ; Yu-Ling LIU
China Journal of Chinese Materia Medica 2025;50(5):1385-1391
This study aims to investigate the scientificity and efficacy of the compatibility of Jinlingzi San from pharmacokinetics. Liquid chromatography-tandem mass spectrometry(LC-MS/MS) was utilized to determine the plasma concentrations of the active components: toosendanin, tetrahydropalmatine A, and tetrahydropalmatine B at various time points following the gavage of Jinlingzi San and its single medicines in rats. Subsequently, WinNonlin was employed to calculate pertinent pharmacokinetic parameters. The pharmacokinetic parameters in rat plasma were compared between the single medicines and the compound formula of Jinlingzi San. It was discovered that the area under the curve(AUC_(all)) and peak concentrations(C_(max)) of tetrahydropalmatine A, and tetrahydropalmatine B were significantly elevated in the compound formula group compared with the single medicine groups. Conversely, the AUC_(all )and C_(max) of toosendanin notably decreased. Furthermore, the compound formula group had longer mean residence time(MRT) and lower apparent clearance(CL/F) of all three active ingredients than the single medicine groups(P<0.05). These findings indicated that Jinlingzi San enhanced the absorption of tetrahydropalmatine A and tetrahydropalmatine B in vivo, facilitating their pharmacological actions. Concurrently, it inhibited the absorption of toosendanin, thereby preventing potential toxic reactions. Moreover, the compatibility prolonged the residence time of the active ingredients in the body. This study provides a reference for exploring the compatibility rationality of Jinlingzi San.
Animals
;
Rats
;
Tandem Mass Spectrometry/methods*
;
Drugs, Chinese Herbal/administration & dosage*
;
Male
;
Rats, Sprague-Dawley
;
Chromatography, Liquid/methods*
;
Berberine Alkaloids/blood*
;
Liquid Chromatography-Mass Spectrometry
7.Mechanism of Jianpi Bushen Yiqi Decoction in promoting AChR clustering and improving neuromuscular junction function in EAMG mice based on Agrin/LRP4/MuSK signaling pathway.
Jia-Hui WANG ; Ru-Ge LIU ; Han-Bin LIU ; Jia-Hao WEI ; Jie ZHANG ; Xue-Ying LIU ; Feng GAO ; Jun-Hong YANG
China Journal of Chinese Materia Medica 2025;50(15):4325-4332
This study investigated the mechanism by which Jianpi Bushen Yiqi Decoction promotes acetylcholine receptor(AChR) clustering in myasthenia gravis through the Agrin/low-density lipoprotein receptor-related protein 4(LRP4)/muscle-specific receptor tyrosine kinases(MuSK) signaling pathway. A total of 114 female C57BL/6J mice were divided into the normal group, modeling group, and solvent control group. The normal group and the solvent control group were immunized with phosphate-buffered saline(PBS), while the modeling group was established as an experimental autoimmune myasthenia gravis(EAMG) model using the murine-derived AChR-α subunit R97-116 peptide fragment. After successful modeling, the mice were randomly assigned to the model group, the low-, medium-, and high-dose Jianpi Bushen Yiqi Decoction groups, and the prednisone group. After four weeks of continuous treatment, muscle strength was assessed using Lennon scores and grip strength tests. Immunofluorescence staining was conducted on differentiated C2C12 myotubes incubated with a drug-containing serum to observe the number of AChR clusters. The integrity of AChR on myofilaments in mouse gastrocnemius muscles was further assessed by immunofluorescence staining. Hematoxylin-Eosin(HE)staining was applied to examine pathological changes in the gastrocnemius muscles of EAMG mice treated with Jianpi Bushen Yiqi Decoction. Western blot was utilized to detect the expression of key proteins in the Agrin/LRP4/MuSK signaling pathway in both C2C12 myotubes and mouse gastrocnemius muscles. The results demonstrated that compared to the model group, the prednisone group exhibited a significant decrease in the body weights of mice, whereas no significant differences in the body weights of mice were observed among the low-, medium-, and high-dose Jianpi Bushen Yiqi Decoction groups. All treatment groups showed significantly improved grip strength and Lennon scores. Additionally, the formula promoted AChR clustering on myotubes and enhanced AChR integrity in gastrocnemius myofilaments and reduced inflammatory infiltration between muscle tissue and fibrous hyperplasia. Furthermore, Jianpi Bushen Yiqi Decoction upregulated the protein expression of AChRα1, Agrin, and p-MuSK in C2C12 myotubes and increased the protein expression of AChRα1, Agrin, MuSK, p-MuSK, LRP4, and docking protein 7(Dok-7)in gastrocnemius tissue. In conclusion, Jianpi Bushen Yiqi Decoction may promote AChR clustering by targeting key proteins in the Agrin/LRP4/MuSK signaling pathway, thereby improving neuromuscular junction function and enhancing muscle strength.
Animals
;
Agrin/genetics*
;
Mice
;
Drugs, Chinese Herbal/administration & dosage*
;
Signal Transduction/drug effects*
;
Receptors, Cholinergic/genetics*
;
Female
;
Mice, Inbred C57BL
;
Receptor Protein-Tyrosine Kinases/genetics*
;
Neuromuscular Junction/metabolism*
;
Myasthenia Gravis, Autoimmune, Experimental/physiopathology*
;
Humans
;
LDL-Receptor Related Proteins
8.Comparison of two transforaminal endoscopic techniques for recurrent L5S1 lumbar disc herniation with high iliac crest.
Yue-Hong GUAN ; Jian WU ; Li-Jun WANG ; Bin XU ; Jian TANG ; Ying ZHANG ; Ying-Qi HE
China Journal of Orthopaedics and Traumatology 2025;38(11):1100-1105
OBJECTIVE:
To explore the clinical efficacy of conventional transforaminal endoscopic technique and I See transforaminal endoscopic technique in the treatment of recurrent L5S1 lumbar disc herniation with high iliac crest.
METHODS:
A total of 36 patients with recurrent L5S1 lumbar disc herniation with high iliac crest after posterior small-incision discectomy, admitted from May 2016 to May 2023, were selected. They were divided into the conventional transforaminal endoscopy group and the I See transforaminal endoscopy group according to the different transforaminal endoscopic techniques adopted, and all patients in both groups underwent lateral transforaminal spinal canal decompression and discectomy. There were 18 patients in the conventional transforaminal endoscopy group, including 11 males and 7 females, with an age of (52.24±6.68) years;the I See transforaminal endoscopy group also had 18 patients, including 12 males and 6 females, with an age of (50.75±7.79) years. The perioperative indicators (operation time, number of intraoperative radiographs, and length of hospital stay) were compared between two groups. The clinical efficacy was evaluated using the visual analogue scale(VAS) for pain, the Japanese Orthopaedic Association(JOA) low back pain score, and the modified MacNab criteria before and after surgery.
RESULTS:
All patients achieved gradeⅠincision healing, with no infection cases. The operation time of the I See group was (64.25±16.67) minutes, which was significantly shorter than that of the conventional transforaminal endoscopy group (89.11±17.24) minutes, and the difference was statistically significant(P<0.05). The number of intraoperative radiographs in the I See group was (5.20±2.29) times, which was significantly less than that in the conventional transforaminal endoscopy group(19.16±3.68) times, and the difference was statistically significant(P<0.05). The VAS and total JOA scores of both groups at the 3rd day, the 3rd month after surgery, and the last follow-up were significantly lower than those before surgery, with statistically significant differences(P<0.05);however, there were no statistically significant differences in VAS and total JOA scores between two groups at the 3rd day, the 3rd month after surgery, and the last follow-up (P>0.05). According to the modified MacNab criteria for efficacy evaluation:in the conventional transforaminal endoscopy group, 14 cases were excellent and 4 cases were good;in the I See transforaminal endoscopy group, 15 cases were excellent and 3 cases were good;there was no statistically significant difference in efficacy between two groups(Z=0.177, P=0.674).
CONCLUSION
Both transforaminal endoscopic techniques have good clinical effects in the treatment of recurrent L5S1 lumbar disc herniation with high iliac crest, resulting in significant improvement of postoperative symptoms, and they are safe, reliable, and minimally invasive surgical methods. Compared with the conventional transforaminal endoscopy, the I See transforaminal endoscopic technique has shorter operation time and fewer intraoperative radiographs, so it is generally the first choice.
Humans
;
Male
;
Female
;
Intervertebral Disc Displacement/surgery*
;
Endoscopy/methods*
;
Middle Aged
;
Lumbar Vertebrae/surgery*
;
Ilium/surgery*
;
Adult
;
Diskectomy/methods*
9.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*
10.Effects of human umbilical cord-derived mesenchymal stem cell therapy for cavernous nerve injury-induced erectile dysfunction in the rat model.
Wei WANG ; Ying LIU ; Zi-Hao ZHOU ; Kun PANG ; Jing-Kai WANG ; Peng-Fei HUAN ; Jing-Ru LU ; Tao ZHU ; Zuo-Bin ZHU ; Cong-Hui HAN
Asian Journal of Andrology 2025;27(4):508-515
Stem cell treatment may enhance erectile dysfunction (ED) in individuals with cavernous nerve injury (CNI). Nevertheless, no investigations have directly ascertained the implications of varying amounts of human umbilical cord-derived mesenchymal stem cells (HUC-MSCs) on ED. We compare the efficacy of three various doses of HUC-MSCs as a therapeutic strategy for ED. Sprague-Dawley rats (total = 175) were randomly allocated into five groups. A total of 35 rats underwent sham surgery and 140 rats endured bilateral CNI and were treated with vehicles or doses of HUC-MSCs (1 × 10 6 cells, 5 × 10 6 cells, and 1 × 10 7 cells in 0.1 ml, respectively). Penile tissues were harvested for histological analysis on 1 day, 3 days, 7 days, 14 days, 28 days, 60 days, and 90 days postsurgery. It was found that varying dosages of HUC-MSCs enhanced the erectile function of rats with bilateral CNI and ED. Moreover, there was no significant disparity in the effectiveness of various dosages of HUC-MSCs. However, the expression of endothelial markers (rat endothelial cell antigen-1 [RECA-1] and endothelial nitric oxide synthase [eNOS]), smooth muscle markers (alpha smooth muscle actin [α-SMA] and desmin), and neural markers (neurofilament [RECA-1] and neurogenic nitric oxide synthase [nNOS]) increased significantly with prolonged treatment time. Masson's staining demonstrated an increased in the smooth muscle cell (SMC)/collagen ratio. Significant changes were detected in the microstructures of various types of cells. In vivo imaging system (IVIS) analysis showed that at the 1 st day, the HUC-MSCs implanted moved to the site of damage. Additionally, the oxidative stress levels were dramatically reduced in the penises of rats administered with HUC-MSCs.
Male
;
Animals
;
Erectile Dysfunction/metabolism*
;
Rats, Sprague-Dawley
;
Mesenchymal Stem Cell Transplantation/methods*
;
Rats
;
Penis/pathology*
;
Humans
;
Disease Models, Animal
;
Umbilical Cord/cytology*
;
Peripheral Nerve Injuries/complications*
;
Mesenchymal Stem Cells
;
Nitric Oxide Synthase Type III/metabolism*
;
Actins/metabolism*
;
Nitric Oxide Synthase Type I/metabolism*

Result Analysis
Print
Save
E-mail