Relationship between frailty and depressive symptoms in older adults: role of activities of daily living and sleep duration.

Introduction: Previous studies have demonstrated that frailty is associated with depressive symptoms among older people and significantly increase the risk of difficulty in activities of daily living (ADL). However, uncertainties remain regarding the mechanisms behind such relationship. The aim of this study was to investigate the mediating effect of ADL in the relationship between frailty and depressive symptoms among older adults in China, and to explore to what extend sleep duration moderated the association between ADL and depressive symptoms. Methods: In this study, we carried out cross-sectional descriptive analysis and 1,429 participants were included in the analysis. A survey was conducted using questionnaires and instruments measuring frailty, depressive symptoms, ADL and sleep duration. Bootstrap analyses served to explore the impact of ADL in mediating frailty and depressed symptoms, as well as the effect of sleep duration in moderating ADL and depressive symptoms. Results: Compared to the robust group, the mediating effects of ADL between frailty and depressive symptoms were significant in the prefrail group and the frail group. The interaction term between sleep duration and ADL was significantly presented in the regression on depressive symptoms. Specifically, the Johnson-Neyman technique determined a range from 8.31 to 10.19 h for sleep duration, within which the detrimental effect of frailty on depressive symptoms was offset. Conclusion: Sleep duration moderated the indirect effect of ADL on the association between frailty and depressive symptoms. This provides support for unraveling the underlying mechanism of the association between frailty and depressive symptoms. Encouraging older adults to enhance ADL and obtain appropriate sleep duration might improve depressive symptoms for older adults with frailty and prefrailty.

Enhancing Inactivated Yellow Fever 17D Vaccine-Induced Immune Responses in Balb/C Mice Using Alum/CpG.

There are some concerns about the safety of live attenuated yellow fever vaccines (YF-live), particularly viscerotropic adverse events, which have a high mortality rate. The cellular production of the vaccine will not cause these adverse effects and has the potential to extend applicability to those who have allergic reactions, immunosuppression, and age. In this study, inactivated yellow fever (YF) was prepared and adsorbed with Alum/CpG. The cellular and humoral immunities were investigated in a mouse model. The results showed that Alum/CpG (20 µg/mL) could significantly increase the binding and neutralizing activities of the antibodies against YF. Moreover, the antibody level at day 28 after one dose was similar to that of the attenuated vaccine, but significantly higher after two doses. At the same time, Alum/CpG significantly increased the levels of IFN-γ and IL-4 cytokines.

Design of a Subretinal Injection Robot Based on the RCM Mechanism.

This study presents an investigation focusing on the advancement of a robot designed for subretinal injections in the context of macular degeneration treatment. The technique of subretinal injection surgery stands as the most efficacious approach for the successful transplantation of stem cells into the retinal pigment epithelium layer. This particular procedure holds immense significance in advancing research and implementing therapeutic strategies involving retinal stem cell transplantation. The execution of artificial subretinal surgery poses considerable challenges which can be effectively addressed through the utilization of subretinal injection surgery robots. The development process involved a comprehensive modeling phase, integrating computer-aided design (CAD) and finite element analysis (FEA) techniques. These simulations facilitated iterative enhancements of the mechanical aspects pertaining to the robotic arm. Furthermore, MATLAB was employed to simulate and visualize the robot's workspace, and independent verification was conducted to ascertain the range of motion for each degree of freedom.

Predicting adverse pregnancy outcomes of pregnant mothers with syphilis based on a logistic regression model: a retrospective study.

Objective: Maternal syphilis could cause serious consequences. The aim of this study was to identify risk factors for maternal syphilis in order to predict an individual's risk of developing adverse pregnancy outcomes (APOs). Methods: A retrospective study was conducted on 768 pregnant women with syphilis. A questionnaire was completed and data analyzed. The data was divided into a training set and a testing set. Using logistic regression to establish predictive models in the training set, and its predictive performance was evaluated in the testing set. The probability of APOs occurrence is presented through a nomogram. Results: Compared with the APOs group, pregnant women in the non-APOs group participated in a longer treatment course. Course, time of the first antenatal care, gestation week at syphilis diagnosis, and gestation age at delivery in weeks were independent predictors of APOs, and they were used to establish the nomogram. Conclusions: Our study investigated the impact of various characteristics of syphilis pregnant women on pregnancy outcomes and established a prediction model of APOs in Suzhou. The incidence of APOs can be reduced by controlling for these risk factors.

An Enzymatic Strategy for the Selective Methylation of High-Value-Added Tetrahydroprotoberberine Alkaloids.

Tetrahydroprotoberberines (THPBs) are plant-specific alkaloids with significant medicinal value. They are present in trace amounts in plants and are difficult to chemically synthesize due to stereoselectivity and an unfavorable environment. In this study, a selective methylation strategy was developed for the biocatalysis of seven high-value-added THPB compounds using 4'-O-methyltransferase (Cj4'OMT), norcoclaurine 6-O-methyltransferase (Cj6OMT), and (S)-scoulerine 9-O-methyltransferase (SiSOMT and PsSOMT) in engineered E. coli. The methyltransferases Cj4'OMT, Cj6OMT, PsSOMT, and SiSOMT were expressed heterologously in E. coli. Compound 1 (10-methoxy-2,3,9-tetrahydroxyberbine) was synthesized using the recombinant E. coli strain Cj4'OMT and the substrate 2,3,9,10-tetrahydroxyberbine. Compound 2 (9-methoxy-2,3,10-tetrahydroxyberbine) was produced in the recombinant Escherichia coli (E. coli) strain PsSOMT, and compounds 2 and 3 (discretamine) were produced in the recombinant E. coli strain SiSOMT. Compounds 4 (9,10-methoxy-2,3-tetrahydroxyberbine) and 5 (corypalmine) were obtained by co-culturing the recombinant strains Cj4'OMT and SiSOMT with substrate. Compounds 6 (scoulerine) and 7 (isoscoulerine) were produced by co-culturing the substrate with the recombinant strains Cj4'OMT and Cj6OMT. To increase the yield of novel compound 2, the flask culture conditions of the engineered SiSOMT strain were optimized, resulting in the production of 165.74 mg/L of this compound. This study thus presents an enzymatic approach to the synthesis of high-value-added THPBs with minimum environmental wastage.

Optimizing sowing patterns in winter wheat can reduce N2O emissions and improve grain yield and NUE by enhancing N uptake.

Increasing nitrogen (N) input is essential to satisfy the rising global wheat demand, but this increases nitrous oxide (N2O) emissions, thereby exacerbating global climate change. Higher yields accompanied by reduced N2O emissions are essential to synergistically reduce greenhouse warming and ensure global food security. In this study, we conducted a trial using two sowing patterns (conventional drilling sowing [CD] and wide belt sowing [WB], with seedling belt widths of 2-3 and 8-10 cm, respectively) with four N rates (0, 168, 240, and 312 kg ha-1, hereafter N0, N168, N240, and N312, respectively) during the 2019-2020 and 2020-2021 growing seasons. We investigated the impacts of growing season, sowing pattern, and N rate on N2O emissions, N2O emissions factors (EFs), global warming potential (GWP), yield-scaled N2O emissions, grain yield, N use efficiency (NUE), plant N uptake and soil inorganic N concentrations at jointing, anthesis, and maturity. The results showed that sowing pattern and N rate interactions influenced the N2O emissions markedly. Compared to CD, WB significantly reduced cumulative N2O emissions, N2O EFs, GWP, and yield-scaled N2O emissions for N168, N240, and N312, with the largest reduction seen at N312. Furthermore, WB markedly improved plant N uptake and reduced soil inorganic N compared to CD at each N rate. Correlation analyses indicated that WB mitigated the N2O emissions at various N rates mainly through efficient N uptake and reduced soil inorganic N. The highest grain yield occurred under a combination of WB and N312, under which the yield-scaled N2O emissions were equal to the local management (sowing with CD at N240). In conclusion, WB sowing could synergistically decrease N2O emissions and obtain high grain yields and NUEs, especially at higher N rates.

An Ultrafast, Energy-Efficient Electrochromic and Thermochromic Device for Smart Windows.

Smart windows nowadays undertake the esteemed obligation of reducing energy consumption as well as upgrading living experience. This project aims to devise a smart window that responds to both electricity and heat, with the intention of achieving energy efficiency, privacy preservation, and enhanced decorative attributes. Through the implementation of a novel electrochromic material design, coupled with the optimization of electrochromic devices (ECDs), a high-performance ECD is obtained, demonstrating coloring/bleaching time of 0.53/0.16 s, a transmittance modulation of 78% (from 99% to 21%), and superior performance in six dimensions. Furthermore, temperature-responsive units and an ionic liquid are incorporated into the electrolyte system to create a novel thermochromic gel electrolyte with transmittance modulation from 80% to 0%, and excellent thermal insulation (6.4 °C reduction). Ultimately, an electro- and thermochromic device is developed, featuring an ultrafast color-switching speed of 0.82/0.60 s and multiple working modes. Overall, this work showcases a prospective design pathway for the development of next-generation ultrafast-switching, and energy-efficient intelligent windows.

Wide-Humidity Range Applicable, Anti-Freezing, and Healable Zwitterionic Hydrogels for Ion-Leakage-Free Iontronic Sensors.

Hydrogels have entered the spotlight for applications in soft electronics. It is essential and challenging to obtain hydrogels that can function properly under varying environmental circumstances, that is, 30-90% relative humidity (RH) and -20 to 40 °C due to their intrinsic nature to lose and absorb water upon variations in humidity and temperature. In this work, a green solvent, solketal, is introduced into poly 3-dimethyl-2-(2-methylprop-2-enoyloxy)ethyl azaniumyl propane-1-sulfonate (poly(DMAPS)) zwitterionic hydrogels. Compared to glycerol, solketal endows hydrogels with greater possibility for further modification as well as improved water content and mechanical performance consistency over 30-90% RH. Encouragingly, the optimized hydrogel demonstrates its unique merits as a dielectric layer in iontronic sensors, featuring non-leaky ions, high sensitivity (1100 kPa-1 ), wide humidity, and temperature range applicability. A wide-humidity range healable and stretchable electrode is attained by combining the hydrogel substrate with Ag paste. A full-device healable and highly-sensitive sensor is developed. This study is a pioneering work that tackles the broad humidity range applicability issue of hydrogels, and demonstrates the ion-leakage-free ionic skins with zwitterionic dielectrics. The outcomes of the study will considerably promote advancements in the fields of hydrogel electronics and iontronic sensors.

Chain Terminators and Glutathione Weaken Wheat Dough under Excess Nitrogen Input.

An excessive nitrogen (N) supply may weaken dough due to an imbalance between N and sulfur (S) in the grains. However, the mechanism underlying the weakening effect of excessive N supply has yet to be fully elucidated. In this study, we evaluated the effect of the N rate × S rate interaction on the ratio of N to S (N/S ratio), grain protein concentration, amount and composition of protein fractions, and dough properties of a bread wheat cultivar. The concentrations of glutathione and modified gliadins with an odd number of cysteine residues (potential chain terminators for glutenins) were also examined. The results revealed that the weakening effect of excess N input is closely associated with an increased gliadin/glutenin ratio, reduced low-molecular-weight glutenin subunit concentrations, and the degree of polymerization of glutenin. More importantly, we found that the increased concentrations of glutathione and chain terminators in grains are involved in the modification of the polymerization degree in glutenins.

MAGEA6 positively regulates MSMO1 and promotes the migration and invasion of oesophageal cancer cells.

The melanoma antigen gene family A (MAGEA) family of proteins comprises of cancer-testis antigens that are highly expressed in a number of tumours but are minimally expressed in normal cells. Due to its expression characteristics, this protein family has become a popular target for anti-cancer drugs and immunotherapy research over recent years. Although, elevated expression levels of MAGEA6 has been found in different types of tumours, there remains to be insufficient information on the function of MAGEA6 and its associated gene regulation pathways. The present study used Transwell, Cell Counting Kit-8 and wound healing assays to analyse the effects of MAGEA6 on Eca109 cell invasion, migration and proliferation. The main functions and pathways involved in MAGEA6 were predicted by Illumina Hiseq screening for mutually regulated genes and core genes. Eca109 cell line with a high expression of MAGEA6 was a stable cell line obtained by transfection in the early stage, and this cell line was used in subsequent experiments. Transcriptome sequencing was performed on this cell line and the Eca109 cell line that normally expressed MAGEA6. It was revealed that a high expression of MAGEA6 conferred a significant stimulating effect on cell proliferation whilst also significantly increasing cell invasion and migration. Transcriptomic analysis identified 14 differentially expressed genes and 13 core regulatory genes closely associated with MAGEA6 expression regulation, such as methylsterol monooxygenase 1 (MSMO1). The present study suggest that MAGEA6 positively regulated MSMO1 expression, which may serve an oncogenic role in cells through this regulatory effect. Overall, this provided a novel route of investigation for an in-depth study of the regulatory function of MAGEA6.

Selective elimination of CML stem/progenitor cells by picropodophyllin in vitro and in vivo is associated with p53 activation.

Chronic myeloid leukemia (CML) is a hematologic malignancy originating from BCR-ABL oncogene-transformed hematopoietic stem cells (HSCs) known as leukemia stem cells (LSCs). Therefore, targeting LSCs is of primary importance to eradicate CML. The present study demonstrates that picropodophyllin (PPP) effectively induces apoptosis and inhibits colony formation in CML stem/progenitor cells as well as quiescent CML progenitors resistant to imatinib therapy, while sparing normal hematopoietic cells in vitro. Administration of PPP in vivo markedly diminishes CML stem/progenitor cells in a transgenic mouse model of CML by inhibition of cell proliferation and enhancement of apoptosis in LSK cells, and significantly improves survival of CML mice. Furthermore, PPP treatment preferentially leads to transcriptional activation of p53 in CML but not normal CD34+ cells, upregulation of p53 protein in LSCs-enriched Sca-1+ cells from CML mice, and increased phosphorylation of p53 and upregulation of Bax protein in Ku812 cells. These results suggest that the inhibitory effects of PPP on CML stem/progenitor cells are associated with selective activation of p53 pathway and propose that PPP is a potent agent that selectively targets CML LSCs, and may be of value in the CML therapy.

[Effect of Etoposide on Elimination of Chronic Myeloid Leukemia Stem Cells by Imatinib in Vivo].

OBJECTIVE: To investigate the effect of etoposide (ETO) on elimination of chronic myeloid leukemia (CML) stem cells by imatinib mesylate(IM) in vivo. METHODS: SCL-tTA/BCR-ABL mice were used as CML animal model. Flow cytometry was used to assess the effect of ETO alone or in combination with IM on the number of leukemia stem cell （LSC） in bone marrow and spleen, and peripheral blood neutrophils in CML mice and normal control FVB mice. RESULTS: The results showed that in CML mice, the number and proportion of LSC in bone marrow and the proportion of neutrophils in peripheral blood decreased significantly after ETO and IM combined treatment, and the degree of decrease was more significant than that of both alone. While in wild type FVB mice, the combination of ETO and IM showed no significant effect on the number and proportion of LSK cells in bone marrow and the proportion of neutrophils in spleen. CONCLUSION: ETO can selectively enhance elimination of CML LSC by IM in vivo.

Identification and characterization of methyltransferases involved in benzylisoquinoline alkaloids biosynthesis from Stephania intermedia.

OBJECTIVES: To characterize methyltransferases involved in the biosynthesis of benzylisoquinoline alkaloids in Stephania intermedia. RESULTS: Three N-methyltransferases, SiCNMT1, SiCNMT2, SiCNMT3, and O-methyltransferase SiSOMT were identified in Stephania intermedia. Then, four methyltransferase genes were cloned into the pGEX-6P-1 vector. The recombinant vectors were transformed into Escherichia coli BL21(DE3) for expression and were functionally tested. SiCNMT1, SiCNMT2, and SiCNMT3 could methylate (R)-coclaurine to produce (R)-N-methylcoclaurine. SiCNMT2 further methylated the product of (R)-N-methylcoclaurine to produce (R)-magnocurarine. Similarly, (R)-norcoclaurine was continuously catalyzed to yield (R)-N-methylnorcoclaurine and (R)-N, N-dimethylnorcoclaurine by SiCNMT2. Furthermore, SiSOMT was shown to catalyze the conversion of (S)-scoulerine to (S)-tetrahydropalmatine. CONCLUSIONS: The key methyltransferases, which were in the last step biosynthesis of (R)-magnocurarine, (R)-N, N-dimethylnorcoclaurine and (S)-tetrahydropalmatine were revealed and their activities were verified in vitro. Four novel methyltransferases will be promising candidates for methylation of benzylisoquinoline alkaloids.

Differentiation, chemical profiles and quality evaluation of five medicinal Stephania species (Menispermaceae) through integrated DNA barcoding, HPLC-QTOF-MS/MS and UHPLC-DAD.

Stephania species is one of the alkaloid-rich genus of the family Menispermaceae. Most plants of the genus Stephania possess medicinal value, whose main components are alkaloids. However, the non-medical species are often mistakenly used as herbs because of the difficulty in identification of the species. A systematic method which involved the combination of DNA barcoding, HPLC-QTOF-MS/MS and UHPLC was established for differentiation, chemical profiles and quality evaluation of medicinal Stephania species. Firstly, twenty batches of Stephania species samples were classified into five Stephania species by DNA barcoding. Secondly, 114 alkaloids including 22 tetrahydroprotoberberines, 13 protoberberines, 27 aporphines, 13 benzylisoquinolines, 12 hasubanans, 3 morphines and 24 other alkaloids were clearly or tentatively identified. Thirdly, thirteen representative components were simultaneously detected by UHPLC-DAD to characterize the differences of chemical compositions among five Stephania species. In conclusion, this method was comprehensive and effective for identification, chemical profiles and quality evaluation of medicinal Stephania species. It will provide a basis for holistic quality evaluation of medicinal Stephania species.

Selective and effective targeting of chronic myeloid leukemia stem cells by topoisomerase II inhibitor etoposide in combination with imatinib mesylate in vitro.

Imatinib mesylate (IM) and other BCR-ABL tyrosine kinase inhibitors (TKIs) have improved chronic myeloid leukemia (CML) patient survival markedly but fail to eradicate quiescent CML leukemia stem cells (LSCs). Thus, strategies targeting LSCs are required to induce long-term remission and achieve cure. Here, we investigated the ability of topoisomerase II (Top II) inhibitor etoposide (Eto) to target CML LSCs. Treatment with Eto combined with IM markedly induced apoptosis in primitive CML CD34+ CD38- stem cells resistant to eradication by IM alone, but not in normal hematopoietic stem cells, CML and normal mature CD34- cells, and other leukemia and lymphoma cell lines. The interaction of IM and Eto significantly inhibited phosphorylation of PDK1, AKT, GSK3, S6, and ERK proteins; increased the expression of pro-apoptotic gene Bax; and decreased the expression of anti-apoptotic gene c-Myc in CML CD34+ cells. Top II inhibitors treatment represents an attractive approach for targeting LSCs in CML patients undergoing TKIs monotherapy.

Silencing of miR-21 sensitizes CML CD34+ stem/progenitor cells to imatinib-induced apoptosis by blocking PI3K/AKT pathway.

BCR-ABL tyrosine kinase inhibitor imatinib fails to eradicate leukemia stem cells (LSCs), the underlying mechanisms maintaining CML LSCs remain poorly understood. Here, we showed that transient inhibition of miR-21 by antagomiR-21 markedly increased imatinib-induced apoptosis in CML, but not normal CD34+ stem/progenitor cells. Furthermore, PI3K inhibitors also significantly sensitized CML CD34+ cells to imatinib-induced apoptosis. MiR-21 or PI3K inhibitor in combination with imatinib treatment significantly decreased AKT phosphorylation and c-Myc expression than either agent did alone, but did not affect Bim and Bcl-6 expresssion. These findings indicate that miR-21 is required for maintaining the imatinib-resistant phenotype of CML CD34+ cells through PI3K/AKT signaling pathway, thus providing the basis for a promising therapeutic approach to eliminate CML LSCs.

Targeting miR-21 sensitizes Ph+ ALL Sup-b15 cells to imatinib-induced apoptosis through upregulation of PTEN.

Philadelphia chromosome positive (Ph+) acute lymphoblastic leukemia (ALL) cells are insensitive to BCR-ABL tyrosine kinase inhibitor imatinib, the underlying mechanisms remain largely unknown. Here, we showed that imatinib treatment induced significant upregulation of miR-21 and downregulation of PTEN in Ph+ ALL cell line Sup-b15. Transient inhibition of miR-21 resulted in increased apoptosis, PTEN upregulation and AKT dephosphorylation, whereas ectopic overexpression of miR-21 further conferred imatinib resistance. Furthermore, knockdown of PTEN protected the cells from imatinib-induced apoptosis achieved by inhibition of miR-21. Additionally, PI3K inhibitors also notably enhanced the effects of imatinib on Sup-b15 cells and primary Ph+ ALL cells similar to miR-21 inhibitor. Therefore, miR-21 contributes to imatinib resistance in Ph+ ALL cells and antagonizing miR-21 demonstrates therapeutic potential by sensitizing the malignancy to imatinib therapy.

Construction and characterization of a thermostable whole-cell chitinolytic enzyme using yeast surface display.

To develop a novel yeast whole-cell biocatalyst by yeast surface display technology that can hydrolyze chitin, the chitinaseC gene from Serratia marcescens AS1.1652 strain was cloned and subcloned into the yeast surface display plasmid pYD1, and the recombinant plasmid pYD1/SmchiC was electroporated into Saccharomyces cerevisiae EBY100 cell. Aga2p-SmChiC fusion protein was expressed and anchored on the yeast cell surface by induction with galactose, which was verified by indirect immunofluorescence and Western blotting. The chitinolytic activity of the yeast whole-cell biocatalyst or partially purified enzyme was detected by agar plate clear zone test, SDS-PAGE zymography and dinitrosalicylic acid method. The results showed that the chitinaseC gene from S. marcescens AS1.1652 strain was successfully cloned and expressed on the yeast cell surface, Aga2p-SmChiC fusion protein with molecular weight (67 kDa) was determined. Tests on the effect of temperature and pH on enzyme activity and stability revealed that the yeast whole-cell biocatalyst and partially purified enzyme possessed both thermal stability and activity, and even maintained some activity under acidic and weakly alkaline conditions. The optimum reaction temperature and pH value were set at 52 °C and 5.0, respectively. Yeast surface display technology succeeded in preparing a yeast whole-cell biocatalyst with chitinolytic activity, and the utilization of chitin could benefit from this process of enzyme preparation.

Wedelia chinensis inhibits nasopharyngeal carcinoma CNE-1 cell growth by inducing G2/M arrest in a Chk1-dependent pathway.

Although Wedelia chinensis, an herb in traditional Chinese medicine, has been widely used for the treatment of inflammation, the effects of W. chinensis on cancer cell growth and the related molecular mechanisms behind these effects have largely remained unexplored to date. In the present study, W. chinensis plant extracts were obtained using either ethanol (E), petroleum ether (PE), ethyl acetate (EA) or butyl alcohol (BA). Then, extracts were examined for bioactivity in vitro via MTT assay in five human cancer cell lines. Our results showed that one subfraction of the EA extract (EA6) was cytotoxic to nasopharyngeal carcinoma (NPC) CNE-1 cells, among all cell lines evaluated. Treatment of CNE-1 cells with EA6 resulted in significant G2/M cell cycle arrest and modest apoptosis. EA6 induced Chk1 activation and inhibition of Chk1 in CNE-1 cells by RNA interference (RNAi) markedly abrogated EA6-mediated G2/M arrest and abolished EA6-induced cytotoxicity. EA6 treatment resulted in notable reduction of c-myc expression in CNE-1 cells, whereas silencing Chk1 inhibited such effects of EA6. Our results indicate that Chk1 is a novel molecular target of EA6 in NPC cells and also suggest an intervention strategy for NPC by EA6 exploring its molecular mechanisms of action.

Scientific evaluation of the subchronic toxicity of Musca domestica larvae extracts in Sprague Dawley rats.

Musca domestica larvae extracts (MDLE) is a potential drug used to treat lipopolysaccharide-induced atherosclerosis pro-inflammatory responses. The purpose of the study was to evaluate the safety of MDLE via a 13-week repeated dose subchronic toxicity test in rats. Both male and female Sprague Dawley rats were divided into four groups, eight animals each from the control and high-dose group (33.0 g/kg) were allocated into recovery groups. The four groups of rats were administrated with MDLE (0, 13.2, 22.0, 33.0 g/kg) in the diet for 13weeks respectively. During the experimental period, the rats were observed for symptoms and signs of gross toxicity daily, food consumption and body weight were measured weekly. Urinalysis, thrombotest, blood biochemical and hematological analyses were performed regularly; Expression of peroxide dismutase gene in liver was quantified and a histopathological examination was also performed. There were no MDLE-induced abnormalities in any of the groups during or after the 13 weeks except the relative weight of liver of high-dose group and middle-dose group was significantly higher than that of control group in male rats (P<0.05). The results indicate a no observed adverse effect level for MDLE is 13.2 and 33.0 g/kg bw/day in male and female rats, respectively.