OBJECTIVE To investigate the effect of bs-5-YHEDA iron chelating peptide combined with semaglutide on the cognitive ability and pathological characteristics of D-Gal-induced Alzheimer's disease(AD) model mice. METHODS Forty mice were randomly divided into 5 groups, namely the healthy control group, PBS group, bs-5-YHEDA iron chelating peptide group, combined treatment group and positive control group, with 8 mice in each group, half of each sex. Except for the healthy control group, D-galactose was injected to induce the AD mice model for 6 weeks. For 3 consecutive weeks starting from the 4th week, the bs-5-YHEDA iron chelating peptide group was injected with bs-5-YHEDA(1 mg·mL–1) once every other day at 200 µL in the tail vein; the bs-5-YHEDA iron chelating peptide(1 mg·mL–1) and semaglutide(25 nmol·kg–1·d–1) were given alternately once a day in the combination treatment group; the positive control group was given memantine(3.3 mg·kg–1·d–1) by gavage every other day. The healthy control group and PBS group were injected with the equal dose of PBS. At the end of treatment, the learning memory ability of mice was detected by the Morris water maze method, whole brain and whole blood were dissected, and pathological changes in hippocampal region were observed by HE staining, and Aβ expression and Tau protein phosphorylation levels were detected by immunohistochemistry, enzyme-linked immunosorbent assay and immunoblotting. RESULTS In the Morris water maze spatial exploration experiment, the differences in the number of times the mice traversed the platform, the ratio of swimming distance to the target quadrant, and the time ratio were statistically significant in each group(P<0.05); compared with the PBS group, the ratio of swimming distance to the target quadrant increased in the combined treatment group, and the differences were statistically significant(P<0.05). The results of HE staining showed that compared with the healthy control mice, the hippocampal area in the PBS group showed reduced levels of pyramidal cells, disorganized arrangement, cell edema, and deep staining of nuclei consolidation. Cellular disorganization, deep staining of nuclei and apoptosis in the hippocampus were significantly improved in each treatment group after drug treatment. Immunohistochemistry and Western blotting results showed that the Aβ expression levels and Tau protein phosphorylation levels were significantly higher in the PBS-administered mice compared with the healthy control mice, and the Aβ expression levels and Tau protein phosphorylation levels were reduced in each group after drug treatment, with statistically significant differences(P<0.01 or P<0.001 ). CONCLUSION The combination of bs-5-YHEDA iron chelating peptide and semaglutide can effectively improve the learning and memory ability and pathological characteristics of AD mice, but from the results of immunohistochemistry and immunoblotting experiments, the improvement of pathological characteristics of AD mice in the combination treatment group is not obvious compared with the single bs-5-YHEDA iron chelating peptide group, suggesting that there may be a threshold effect of our designed dual-target combination treatment on the cognitive improvement of AD mice, and the optimization and validation of the effect of multi-target combination treatment need further study.

AIM:To investigate the effect of a disintegrin and metalloproteinase(ADAM)domain-like decy-sin 1(ADAMDEC1)knockdown on the proliferation,migration and invasion of pancreatic carcinoma cells.METHODS:Expression levels of ADAMDEC1 in pancreatic carcinoma tissues were analyzed using the GEPIA and UALCAN online da-tabases.Western blot analysis was employed to detect the protein expression levels of ADAMDEC1 in pancreatic carcino-ma cell lines(MIA PaCa-2 and PANC-1)and pancreatic ductal cell line(hTERT-HPNE).The effects of ADAMDEC1 knockdown on cell proliferation,migration and invasion were evaluated using CCK-8,colony formation,wound-healing and Transwell assays.Additionally,Western blot analysis was used to detect the effects of ADAMDEC1 knockdown on the expression levels of migration and invasion markers,as well as Wnt/β-catenin signaling pathway-related proteins in pancre-atic carcinoma cells.Furthermore,a recovery experiment was conducted to assess the role of Wnt/β-catenin signaling path-way agonist CHIR-99021 in ADAMDEC1 knockdown-induced inhibition of pancreatic carcinoma cell growth and migra-tion.RESULTS:(1)ADAMDEC1 was highly expressed in pancreatic carcinoma cells.(2)Knockdown of ADAMDEC1 led to a significant reduction in the proliferation,migration and invasion of pancreatic carcinoma cells.(3)Knockdown of ADAMDEC1 resulted in increased E-cadherin protein expression and decreased levels of matrix metalloproteinase 9,N-cadherin and vimentin proteins,alongside a reduction in the expression of Wnt/β-catenin signaling pathway-related pro-teins.(4)Co-treatment of pancreatic carcinoma cells with CHIR-99021 and ADAMDEC1 small interfering RNA reversed the inhibitory effects of ADAMDEC1 knockdown on cell proliferation,migration,and invasion.CONCLUSION:ADAMDEC1 is highly expressed in pancreatic carcinoma.Targeted silencing of ADAMDEC1 has the potential to inhibit the prolifera-tion,migration and invasion of pancreatic carcinoma cells by regulating the Wnt/β-catenin signaling pathway.

The extraordinary advantages associated with mRNA vaccines, including their high efficiency, relatively low severity of side effects, and ease of manufacture, have enabled them to be a promising immunotherapy approach against various infectious diseases and cancers. Nevertheless, most mRNA delivery carriers have many disadvantages, such as high toxicity, poor biocompatibility, and low efficiency in vivo, which have hindered the widespread use of mRNA vaccines. To further characterize and solve these problems and develop a new type of safe and efficient mRNA delivery carrier, a negatively charged SA@DOTAP-mRNA nanovaccine was prepared in this study by coating DOTAP-mRNA with the natural anionic polymer sodium alginate (SA). Intriguingly, the transfection efficiency of SA@DOTAP-mRNA was significantly higher than that of DOTAP-mRNA, which was not due to the increase in cellular uptake but was associated with changes in the endocytosis pathway and the strong lysosome escape ability of SA@DOTAP-mRNA. In addition, we found that SA significantly increased the expression of LUC-mRNA in mice and achieved certain spleen targeting. Finally, we confirmed that SA@DOTAP-mRNA had a stronger antigen-presenting ability in E. G7-OVA tumor-bearing mice, dramatically inducing the proliferation of OVA-specific CLTs and ameliorating the antitumor effect. Therefore, we firmly believe that the coating strategy applied to cationic liposome/mRNA complexes is of potential research value in the field of mRNA delivery and has promising clinical application prospects.

Objective:To analyze and evaluate the safety and efficacy of a Chinese domestically manufactured Heart Con-type implantable third-generation magnetic and hydrodynamic levitation left ventricular assist device(LVAD) for the treatment of end-stage heart failure(ESHF), by reporting the results of eleven-center clinical trial on 50 cases.Methods:This study was a multicenter clinical trial, designed by means of prospective, multicenter and single-group target value. 50 subjects with ESHF were competitively enrolled and treated with HeartCon as the LVAD in eleven centers. The primary efficacy measure was survival, defined as either the subjects experiencing the transition to heart transplantation(HT) or myocardial recovery assisted by the device within 90 days, or as successfully assisted by the LVAD for full 90 days after implantation. The target survival rate was 60%, other observations included implantation success rate, mortality, pump failure needing replacement or emergency heart transplantation.Results:All enrolled 50 patients received LVAD implantation successfully, 46 survived with the pump for 90 days, 1 patient transitioned to heart transplantation, and 3 patients experienced pump thrombosis, within which 2 patients underwent pump replacement and continued to live with the pump for 90 days, and the other one received emergency heart transplantation. There were no dropout subjects. The survival rate at full 90 days after HeartCon implantation was 100%. The survival rates with pump in the full set analysis and the protocol set analysis were 96.00% and 95.92% respectively, which were higher than the target value of 60%. The differences were both statistically significant( P<0.05). Conclusion:The results of the multicenter clinical trial with the largest sample size in China using domestically manufactured third-generation LVAD has demonstrated that, HeartCon is a safe and effective LVAD to treat ESHF patients.

{L-End}Objective To explore the feasibility of using positron emission tomography (PET) -computed tomography (CT) to detect brain metabolic abnormalities caused by trimethyltin chloride (TMT) poisoning. {L-End}Methods Specific pathogen free healthy SD rats were randomly divided into model group and control group with six rats in each group. Rats in the model group were intraperitoneally injected with a single dose of 10 mg/kg body mass of TMT solution, and rats in the control group were intraperitoneally injected with a single dose of an equal volume of 0.9% sodium chloride solution. Rats were anaesthetized after three days of modeling and underwent PET-CT brain scanning to detect the standardized uptake value (SUV) of ¹⁸F-2-fluro-D-deoxy-glucose (¹⁸F-FDG). After scanning, rats were sacrificed and brain tissues were collected for brain organ coefficients calculation and brain histopathological analysis. {L-End}Results The rats in the model group showed symptoms of head tremor, limb twitching, irritability and others after TMT modeling. There was no significant difference in the body mass between the two groups of rats on the third day of modeling (P>0.05). The ¹⁸F-FDG uptake in the cerebral cortex, cerebellum and brainstem of the rats in the model group was significantly weakened compared with the control group, with deceased SUV values (all P<0.05). No obvious abnormalities were found in CT images and freshly collected brain tissues of rats of the control and model groups. The brain organ coefficients of rats in the two groups showed no significant difference (P>0.05). The results of hematoxylin-eosin staining of brain tissue showed that the cerebral cortex of rats in the model group had more tiny cavities than that of the control group, and some neuronal cells and a small number of hippocampal vertebral cells were tightly and deeply stained, with the cytoplasm and nucleus poorly demarcated, and pericellular space enlarged. The results of Nissen staining showed that the arrangement of neuronal cells in the model group was slightly disordered, and the interstitial space was slightly enlarged, but no other significant abnormal changes were observed. {L-End}Conclusion PET-CT can be used in detecting the metabolic abnormalities of brain in TMT poisoning rat model, making it a sensitive detection method for TMT poisoning.

Objective To analyze result of the external quality assessment for laboratories of toxicological pathology diagnosis in organizations in China. Methods A total of 86 organizations that participated in the 2020-2021 external quality assessment in laboratory of toxicological pathology diagnosis (hereinafter referred to as "reference units") were selected as research subjects using convenient sampling method, and the assessment results were analyzed. Results The median of total score was 92, and the 0-100 percentiles were 64-100 in these 86 reference units. Among these reference units, 76 were rated as excellent, 10 as qualified, with the excellent and the qualified rate of 88.4% and 11.6%, respectively. No reference unit was rated as unqualified. The rates of excellence of the reference units in public health institutions, pharmaceutical research institutions, drug safety evaluation centers and testing companies were 95.7%, 84.2%, 85.7% and 86.7%, and the qualified rates were 4.3%, 15.8%, 14.3% and 13.3%, respectively. The distribution of excellence and qualification among the four types of reference units showed no statistical difference (P>0.05). The distribution of sample scores according to the three grades of poor, good, and excellent were 4.9%, 20.7%, and 74.5% in public health institutions, 8.6%, 23.7%, and 67.8% in pharmaceutical research institutions, 12.5%, 25.0%, and 62.5% in drug safety evaluation centers, and 5.4%, 17.5%, and 77.1% in testing companies. The proportion of excellence unit in public health institutions was higher than that in pharmaceutical research institutions (P<0.05). Conclusion The overall toxicological pathology diagnostic capabilities in China are good, and various types of reference units demonstrate comparable technical capabilities. However, there is a need for standardization of diagnostic terminology.

OBJECTIVE: To evaluate the diagnostic ability of toxicity pathology in patho-toxicological testing institutions in China. METHODS: The institutions participated in the 2018 Interlaboratory Comparison Activity of Toxicity Pathology Testing(hereinafter referred to as reference unit) were selected as the research subjects. The heart, spleen, skin, soft tissue, liver and mammary gland of SD rats of different groups in the 2-year carcinogenesis test were selected. The femur, knee joint and nose of Beagle dogs in the 4-week toxicity test and a total of 10 pathological tissues were selected as the comparison samples. The pathological diagnosis was carried out by the pathological diagnostic personnel of the reference unit, and the diagnostic results were reported. The expert appointed by the Toxicology and Pathology Committee of Chinese Toxicology Association compared the diagnostic results with the appointed value. RESULTS: A total of 167 pathological diagnostic personnel from 75 reference units in 24 provinces and municipalities participated in the comparison activity. The reference units were mainly distributed in East China, South China and North China, accounting for 77.3%(58/75). Totally 75 reference units fed back 750 effective diagnostic results. The qualified rates of diagnosis on heart, spleen, skin, soft tissue and breast samples were higher than 60.0%. The qualified rates of diagnosis on femur and knee joint, and nose samples were low(30.7% and 6.7%, respectively). There were 1(1.3%), 46(61.4%) and 28(37.3%) reference units rated as unqualified, qualified and excellent, respectively. CONCLUSION: Most of the testing institutions in China have a high level of patho-toxicological diagnostic ability, that can provide reliable diagnostic results for toxicology safety evaluation tests.

OBJECTIVE: To investigate the chronic toxicity and carcinogenicity of kresoxim-methyl in rats. METHODS: Specific pathogen free SD rats were randomly divided into control group and low-, medium-and high-dose groups according to the body weight of rats, 120 rats in each group with half male and half female rats. The chronic toxicity and carcinogenesis was induced in rats for 104 weeks by oral feeding. The dose of kresoxim-methyl in feed of male and female rats was 0, 75, 300 and 1 200 mg/kg. During the process of experiment, the body weight of rats was weighed. The blood biochemistry, organ coefficient and histopathology were examined at the end of the exposure, and the tumor incidence was calculated. RESULTS: There was no significant difference in mortality of the female or male rats in the four groups(P>0.05). At the 32 nd, 48 th and 56 th week after exposure, the body mass of female rats in the high dose group was lower than that in control group(P<0.05); at the 8 th, 16 th, 24 th and 32 nd week, the body mass of male rats in the high dose group was lower than that in the control group(P<0.05). The organ coefficients of heart and adrenal gland of female rats in the high dose group were higher than those in the control group and the low dose group(P<0.05). The organ coefficient of liver of male rats in the high dose group was lower than that in the control group(P<0.05). The alkaline phosphatase of male rats in the three dose groups was lower than that in the control group(P<0.05). The blood glucose of male rats in the high dose group was higher than that in the control group(P<0.05). The aspartate aminotransferase of male rats in the high dose group was lower than that in the control group(P<0.05). There was no significant difference among the three indexes in female rats(P>0.05). The tumor incidence of the control group and the low, medium and high dose groups were 68.3%, 75.0%, 75.0% and 78.8%, respectively, with no significant difference(P>0.05). The tumor incidence of the female rats was higher than that of the male rats(87.0% vs 61.5%,P<0.01).The tumor multiplicity of the above four groups were 38.3%, 35.8%, 35.0%, 39.8%, respectively, with no significant difference(P>0.05). The tumor multiplicity in female rats was higher than that in male rats(56.9% vs 17.6%,P<0.01). CONCLUSION: The no observed adverse effect level of kresoxim-methyl to female and male SD rats was 24.726 and 20.002 mg/(kg·d), respectively. No carcinogenicity of kresoxim-methyl to SD rats was observed.

OBJECTIVE: To observe the pathological changes of rat silicosis model at different time points. METHODS: The specific pathogen free SD rats were randomly divided into control group and 7, 15, 21, 30, 45, 60, 75 and 90 day model groups based on their body weight, with 5 rats in each group. Non-exposed endotracheal intubation was performed. Silicosis rat model was established by intratracheal instillation of 250 g/L silica suspension in each rat, and 0.9% sodium chloride solution was perfused into the trachea of rats in the control group. The rats in the control group were sacrificed on the 90 th day after exposure, and the model rats in the other 8 groups were sacrificed on the 7 th, 15 th, 21 st, 30 th, 45 th, 60 th, 75 th and 90 th days after the end of exposure. The gross appearance of the lung tissue of rats was observed. The rat lung tissues were stained with hematoxylin-eosin and Masson staining to observe the pathological changes, and Ashcroft score was evaluated. RESULTS: The gross observation showed that the lungs of rats in the model groups had varying degree of gray changes, hardened texture, and spots and nodules on the surface of the lobes. These changes were aggravated with the increase of time after dust exposure. The results of histopathological examination of the lungs showed that the rats developed acute alveolar inflammation, and a large number of macrophages and neutrophils were seen in the lung tissues in the 7 th and 15 th day model groups. Cellular nodules appeared in the lung tissue, and fibrosis appeared in the center of the nodule in the rats of 21 st, 30 th, and the 45 th day model groups; the silicosis nodules appeared in the lung tissues of rats in the 60 th, 75 th, and 90 th day model groups, and the small nodules gradually merged into larger ones. Simultaneously, with the increase of time after dust exposure, the lung tissue of rats gradually showed severe pulmonary fibrosis. The lung organ coefficient and Aschcroft score of rats increased with the increase of time after dust exposure(P<0.01). CONCLUSION: The rat lung changes after dust exposure. Acute alveolar inflammation occurs on the 7 th to 15 th day after dust exposure; cellular nodules develop on the 21 st to 45 th day after dust exposure; silicosis nodules develop on the 60 th to 90 th day after dust exposure. The severity of lung fibrosis after dust exposure showed a time-effect relationship in rats.

Objective: To assess clinical effect and safety of botulinum toxin A injection in external urethral sphincter for male patient with neurogenic detrusor underactivity(DU). Methods: A prospective and self-controlled trail was conducted from August 2012 to October 2017. Male patients with nerve injury, dysuria more than 6 months, DU(bladder contractility index less than 100) were enrolled in this study. Exclusion criteria included patients with acute urinary tract infection, bladder stone, benign prostate hyperplasia, urethral stricture and urethral diverticulum.100 IU BTX-A was dissolved in 4ml normal saline, and the solution of BTX- A was injected into 4 different points(3-o’clock, 6-o’clock, 9-o’clock, and 12-o’clock) in external urinary sphincter with each point of 1ml solution. Patients were evaluated at baseline and 12 weeks after injection. The outcomes included post void residual (PVR), maximum flow rate (Q_max), maximum detrusor pressure during voiding phases (P_det.max), maximum urethral closure pressure (MUCP), the case number of intermittent catheterization (IC)and the score of quality of life (QOL score). Adverse events were also recorded. Results: A total of 58 male patients (all from Guangdong provincial work injury rehabilitation hospital)with mean age 28.6 years suffered from cerebral palsy (n=2), cerebrovascular accident(n=19)and spinal cord injury(n=37) were included into the study. Compared to baseline data, significant difference were observed at week 12 in PVR (56.68 ml vs. 280.11 ml, P<0.001), P_det.max(23.95 cmH₂O vs. 30.01 cmH₂O, P=0.019), Q_max(6.74 ml/s vs. 3.28 ml/s, P=0.042), MUCP(48.25 cmH₂O vs. 79.34 cmH₂O, P<0.001), the case number of IC(40 vs. 58, P<0.001) and QOL score(3.63 vs.5.22, P<0.001) respectively. 5 cases developed perineal pain and 16 cases developed mild transient haematuria. These adverse events were disappeared by medical symptomatic treatment during 3-5 days. Conclusions BTX-A externalurethral sphincter injections help reduce urethra resistance and also improve the quality of life for patients with neurogenic detrusor underactivity.