Alzheimer's disease (AD) is the commonest neurodegenerative disease that causes memory decline, cognitive dysfunction and behavior disorders in the aged people. Primary pathological hallmarks of AD include amyloid-β (Aβ), neurofibrillary tangles (NFTs), gliosis, and neuronal loss. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels have important physiological functions, especially in aspects of controlling the resting membrane potential, pacemaker activity, memory formation, sleep and arousal. This article reviews the structure, distribution, regulation of HCN channels and the role of HCN channels in the pathological mechanisms of AD, aiming to provide drug therapeutic targets for the prevention and treatment of AD.
Humans ; Alzheimer Disease/physiopathology* ; Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels/physiology* ; Animals ; Amyloid beta-Peptides/metabolism*

This study aimed to explore the effects and mechanisms of total extracts from Anthriscus sylvestris on pulmonary hypertension in rats. Sixty male SD rats were divided into normal(NC) group, model(M) group, positive drug sildenafil(Y) group, low-dose A. sylvestris(ES-L) group, medium-dose A. sylvestris(ES-M) group, and high-dose A. sylvestris(ES-H) group. On day 1, rats were intraperitoneally injected with monocrotaline(60 mg·kg~(-1)) to induce pulmonary hypertension, and the rat model was established on day 28. From days 15 to 28, intragastric administration of the respective treatments was performed. After modeling and treatment, small animal echocardiography was used to detect the right heart function of the rats. Arterial blood gas was measured using a blood gas analyzer. Hematoxylin and eosin(HE) staining and Masson staining were performed to observe cardiopulmonary pathological damage. Flow cytometry was used to detect apoptosis in the lung and myocardial tissues and reactive oxygen species(ROS) levels. Western blot was applied to detect the expression levels of transforming growth factor-β1(TGF-β1), phosphorylated mothers against decapentaplegic homolog 3(p-Smad3), Smad3, tissue plasminogen activator(t-PA), and plasminogen activator inhibitor-1(PAI-1) in lung tissue. A blood routine analyzer was used to measure inflammatory immune cell levels in the blood. Enzyme-linked immunosorbent assay(ELISA) was used to detect the expression levels of P-selectin and thromboxane A2(TXA2) in plasma. The results showed that, compared with the NC group, right heart hypertrophy index, right ventricular free wall thickness, right heart internal diameter, partial carbon dioxide pressure(PaCO_2), apoptosis in cardiopulmonary tissue, and ROS levels were significantly increased in the M group. In contrast, the ratio of pulmonary blood flow acceleration time(PAT)/ejection time(PET), right cardiac output, change rate of right ventricular systolic area, systolic displacement of the tricuspid ring, oxygen partial pressure(PaO_2), and blood oxygen saturation(SaO_2) were significantly decreased in the M group. After administration of the total extract of A. sylvestris, right heart function and blood gas levels were significantly improved, while apoptosis in cardiopulmonary tissue and ROS levels significantly decreased. Further testing revealed that the total extract of A. sylvestris significantly decreased the levels of interleukin-1β(IL-1β), interleukin-6(IL-6), and PAI-1 proteins in lung tissue, while increasing the expression of t-PA. Additionally, the extract reduced the levels of inflammatory cells such as leukocytes, lymphocytes, granulocytes, and monocytes in the blood, as well as the levels of P-selectin and TXA2 in plasma. Metabolomics results showed that the total extract of A. sylvestris significantly affected metabolic pathways, including arginine biosynthesis, tyrosine metabolism, and taurine and hypotaurine metabolism. In conclusion, the total extract of A. sylvestris may exert an anti-pulmonary hypertension effect by inhibiting the TGF-β1/Smad3 signaling pathway, thereby alleviating immune-inflammatory responses and thrombosis.
Animals ; Male ; Smad3 Protein/metabolism* ; Transforming Growth Factor beta1/metabolism* ; Rats, Sprague-Dawley ; Rats ; Signal Transduction/drug effects* ; Hypertension, Pulmonary/genetics* ; Thrombosis/immunology* ; Drugs, Chinese Herbal/administration & dosage* ; Humans ; Apoptosis/drug effects*

Objective To investigate the role and underlying mechanisms of miR-34a/SIRT1 in intensive care unit acquired weakness(ICU-AW).Methods(1)C2C12 mouse skeletal muscle cells were induced to differentiate into myotubes,and were divided into two groups:model group[ICU-AW group,treated with lipopolysaccharides(LPS)for 12 hours]and normal control group(treated with the same amount of sterile water for 12 hours).Western blotting was used to detect the protein expression level of Muscle ring finger 1(MuRF-1),atrophy gene 1(Atrogin-1)and Sirtuin-1(SIRT1).RT-qPCR was used to assess the mRNA expression level of microRNA-34a(miR-34a),MuRF-1,Atrogin-1 and SIRT1,and light microscope was used to observe the growth and differentiation of C2C12 skeletal muscle cells in each group.(2)ICU-AW cells were further subdivided into control group(treated with siRNA transfection agent intervention),Scra siRNA group(treated with transfection agent and non-specific siRNA),miR-34a siRNA group(treated with transfection agent and specific siRNA intervention),vehicle group(treated with agonist solvent dimethyl sulfoxide)and SRT1720 group(treated with SIRT1 agonist SRT1720).Western blotting was used to detect the protein expression level of SIRT1,Atrogin-1 and MuRF-1 in each group.RT-qPCR was used to detect the miR-34a and the mRNA expression level of SIRT1,Atrogin-1 and MuRF-1 in each group.(3)In addition,another group of ICU-AW cells were divided into control group(treated with siRNA transfection),miR-34a siRNA group(treated with transfection agent and specific siRNA intervention),miR-34a siRNA+vehicle group(treated with transfection agent,specific siRNA and Dimethyl sulfoxide intervention)and miR-34a siRNA+EX-527 group(treated with transfection agent,specific siRNA and SIRT1 inhibitor EX-527).Western blotting was used to detect the protein expression level of Atrogin-1 and MuRF-1.RT-qPCR was used to assess the mRNA expression level of Atrogin-1 and MuRF-1.Results Myotube differentiation was observed on the 4th day.Compared with control group,myotube atrophy was obvious in ICU-AW group.RT-qPCR and Western blotting results revealed that,compared with normal control group,in ICU-AW group,the mRNA and protein expression levels of Atrogin-1 and MuRF-1 significantly increased(P＜0.05),and the expression level of miR-34a significantly increased(P＜0.05),while the mRNA and protein expression levels of SIRT1 significantly decreased(P＜0.05).RT-qPCR results showed that,compared with control group(treated with siRNA transfection agent intervention)and Scra siRNA group,the expression of miR-34a and mRNA expression of Atrogin-1 and MuRF-1 in miR-34a siRNA group significantly decreased(P＜0.05),while the mRNA expression of SIRT1 significantly increased(P＜0.05),meanwhile the protein expression of Atrogin-1 and MuRF-1 decreased significantly(P＜0.01),and the protein expression of SIRT1 significantly increased(P＜0.05).RT-qPCR results also showed that,compared with vehicle group,the mRNA expression of Atrogin-1 and MuRF-1 in SRT1720 group decreased significantly(P＜0.05),while SIRT1 increased significantly(P＜0.05).Western blotting results demonstrated that,compared with control group and Scra siRNA group,the protein expression of Atrogin-1 and MuRF-1 in miR-34a siRNA group decreased significantly(P＜0.05),while SIRT1 increased significantly(P＜0.05).RT-qPCR and Western blotting results indicated that,compared with miR-34a siRNA+vehicle group,the mRNA and protein expression of Atrogin-1 and MuRF-1 in miR-34a siRNA+EX-527 group increased significantly(P＜0.05).Conclusion Overactivation of miR-34a in ICU-AW contributes to skeletal muscle atrophy by inhibiting the expression of SIRT1,which may play an important role in the pathogenesis of ICU-AW.

Objective To establish a renal cell co-culture system to simulate the renal barrier system,and to test its responsiveness to different glucose concentrations,and to investigate the regulatory effect of miR-29b-3p on osteopontin(OPN)/transforming growth factor β(TGF-β)pathway and the changes of this pathway under high glucose condition.Methods The three-cell co-culture system consisting of human renal podocytes,human glomerular mesangial cells and human renal tubular epithelial cells was established to test the cell viability and glucose consumption value at glucose concentrations of 5,8,12 and 16 mmol/L.The content of TGF-β and OPN in cell supernatant was measured.The recombinant plasmid and siRNA of OPN were transfected,and the expressions of TGF-β and OPN were detected by Q-PCR and Western blot.Results The mRNA expressions of OPN,TGF-β and miR-29b were significantly increased at 12 mmol/L glucose conditions.Western blot results showed that the protein expression of OPN increased in high glucose conditions,while the protein expression of TGF-β did not change significantly.After adding miR-29b-3p activator,the mRNA levels of OPN and TGF-β in the cell supernatant were significantly increased.After adding miR-29b-3p inhibitor,the mRNA levels of OPN and TGF-β in the cell supernatant were significantly decreased.Western blot results showed that compared with 5 mmol/L glucose,the protein expressions of OPN and TGF-β were increased by miR-29b-3p activator,and the protein expressions of OPN and TGF-β were decreased by miR-29b-3p inhibitor.After transfection with OPN recombinant plasmid,the content of TGF-β in the cell supernatant was significantly increased,and the mRNA expressions of OPN and TGF-β in the cells were significantly increased.After transfection with OPN siRNA,the content of TGF-β in the cell supernatant was decreased,and the expression of OPN mRNA in the cells was significantly decreased,but the expression of TGF-β mRNA was not significantly increased.Conclusion The renal cell co-culture system can mimic the complex renal environment in vivo.When induced by high glucose,cell proliferation is inhibited,glucose consumption is increased,and the content of TGF-β in the cell supernatant is increased,and miR-29b-3p has a regulatory effect on OPN/TGF-β signaling pathway in the co-culture system.

The upper and lower limb motor rehabiliation training devices were introduced in terms of classification,working principle and inspection standard.The causes for unqualification of the devices were analyzed in input power,touch current under single-fault condition,emergency stop mechanism,activation time of spastic protection,extrusion of moving parts and emergency voice-controlled switch,and the countermeasures were put forward accordingly.References were provided for decreasing the safety risks of similar devices and increasing the qualification rate of type inspection.[Chinese Medical Equipment Journal,2024,45(2):87-91]

Objective To develop a multicolor photoelectroencephalography evoked flash to identify photosensitive epilepsy patients during the selection of naval aircraft pilots.Methods The multicolor photoelectroencephalography evoked flash was composed of a main body,a control box and a bracket.There were four rows of LED lights in the main body,which emitted four colors of light including red,yellow,green and orange,respectively;there were three sockets for signal,light and power and one color changeover switch on the body of the control box,and a control circuit board was fixed at the bottom inside the control box;the bracket had a double-jointed arm folding structure.The flash developed was compared with the coventional photoelectroencephalography evoked flash to verify its effect for inducing photosensitive epilepsy.Results There were no significant differences between the two flashes in the numbers of identified cases with photosensitive epilepsy when the subjects were under awake and closed-eye conditions(P＞0.05).Condusion The flash developed can make up for the deficiency of the coventional photoelectroencephalography evoked flash when selecting naval aircraft pilots.[Chinese Medical Equipment Journal,2024,45(7):112-114]

The World Health Organization has declared that the outbreak of coronavirus disease 2019(COVID-19) is a global pandemic. As mutations occurred in the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the global epidemic still needs further concern. Worryingly, the effectiveness and neutralizing activity of existing antibodies and vaccines against SARS-CoV-2 variants is declining. There is an urgent need to find an effective antiviral medication with broad-spectrum inhibitory effects on novel coronavirus mutant strains against the SARS-CoV-2 infection. Neutralizing antibodies play an important role in the prevention and treatment of COVID-19. The interaction of spike-receptor-binding domain (Spike-RBD) of SARS-CoV-2 and human angiotensin-converting enzyme 2 (ACE2) is the first and critical step of SARS-CoV-2 infection. Hence, the SARS-CoV-2 Spike-RBD is a hot target for neutralizing antibodies development. Evusheld, the combination of Tixagevimab and Cilgavimab monoclonal antibodies (mAbs) targeting Spike-RBD exhibits neutralizing activity against BA.2.12.1, BA.4 and BA.5, which could be used as pre-exposure prophylaxis against SARS-CoV-2 infection. The nucleocapsid (N) protein is a conservative and high-abundance structural protein of SARS-CoV-2. The nCoV396 monoclonal antibody, isolated from the blood of convalescent COVID-19 patients against the N protein of SARS-CoV-2. This mAb not only showed neutralizing activity but also inhibits hyperactivation of complement and lung injury induced by N protein. The mAb 3E8 targeting ACE2 showed broadly neutralizing activity against SARS-CoV-2 and D614G, B.1.1.7, B.1.351, B.1.617.1 and P.1 variants in vitro and in vivo, but did not impact the biological activity of ACE2. Compared with neutralizing antibodies, small molecule inhibitors have several advantages, such as broad-spectrum inhibitory effect, low cost, and simple administration methods. Several small-molecule inhibitors disrupt viral binding by targeting the ACE2 and N-terminal domain (NTD) of SARS-CoV-2 spike protein. Known drugs such as chloroquine and hydroxychloroquine could also block the infection of SARS-CoV-2 by interacting with residue Lys353 in the peptidase domain of ACE2. The transmembrane protease serine 2 (TMPRSS2) inhibitors Camostat mesylate and Proxalutamide inhibit infection by blocking TMPRSS2 mediates viral membrane fusion. The main protease inhibitor Paxlovid and RNA-dependent RNA polymerase inhibitor Azvudine have been approved for treatment of COVID-19 patients. This review summarizes the current research status of neutralizing antibodies and small molecule inhibitors and prospects for their application. We expect to provide more valuable information for further studies in this field.

Objective To clarify the expression and distribution of brain⁃derived neurotrophic factor (BDNF) in the cerebrum of plateau yaks and cattle, and to explore the relationship between BDNF function and the adaptability of altitude hypoxia. Methods Five yaks and five cattles were selected.The content and distribution of BDNF in frontal lobe, temporal lobe, parietal lobe, occipital lobe, cerebrum white matter and hippocampus of yak and cattle were analyzed by Real⁃time PCR, Western blotting and Immunohistochemistry. Results Real⁃time PCR result showed that BDNF mRNA expression in the cerebrum of yaks and cattles was highest in temporal cortex, followed by hippocampus, parietal cortex, occipital cortex and frontal cortex, and lowest in white matter. Western blotting results showed that the content of BDNF protein in the cerebrum of yaks was the highest in temporal cortex,followed by hippocampus. The content of BDNF protein in other tissues was parietal cortex, frontal cortex and cerebrum white matter, and the content of BDNF protein was the lowest in occipital cortex. The content of BDNF protein intlecerebrum of cattles was the highest in the temporal cortex, followed by the hippocampus. The content of BDNF protein in other tissues was parietal cortex, occipital cortex and frontal cortex in descending order, and the protein content in cerebrum white matter was the lowest. Immunohistochemical results showed that the positive expression of BDNF protein in the cerebrum of yaks and cattles was basically similar, mainly distributed in the granulosa cells and glial cells in the frontal cortex, temporal cortex, parietal cortex and occipital cortex, glial cells in cerebrum white matter, pyramidal cell layer and polyform cell layer in the hippocampus. There was the small amount of distribution in Martinotti cells and the molecular layer of hippocampus in the cerebral cortex. Conclusion BDNF mRNA and protein are distributed and expressed in different brain regions of yaks and cattles, but the expression level different, which is speculated to be closely related to the specific functions of different cerebrum regions. The expression level of the cerebrum of yak is higher than that of cattle except occipital cortex, suggesting that it is related to the altitude hypoxic environment. BDNF may play an important role in enhancing hypoxic tolerance and protecting internal environmental homeostasis in the process of animal adaptation to hypoxic environment.

ObjectiveTriple-negative breast cancer (TNBC) is the breast cancer subtype with the worst prognosis, and lacks effective therapeutic targets. Colony stimulating factors (CSFs) are cytokines that can regulate the production of blood cells and stimulate the growth and development of immune cells, playing an important role in the malignant progression of TNBC. This article aims to construct a novel prognostic model based on the expression of colony stimulating factors-related genes (CRGs), and analyze the sensitivity of TNBC patients to immunotherapy and drug therapy. MethodsWe downloaded CRGs from public databases and screened for differentially expressed CRGs between normal and TNBC tissues in the TCGA-BRCA database. Through LASSO Cox regression analysis, we constructed a prognostic model and stratified TNBC patients into high-risk and low-risk groups based on the colony stimulating factors-related genes risk score (CRRS). We further analyzed the correlation between CRRS and patient prognosis, clinical features, tumor microenvironment (TME) in both high-risk and low-risk groups, and evaluated the relationship between CRRS and sensitivity to immunotherapy and drug therapy. ResultsWe identified 842 differentially expressed CRGs in breast cancer tissues of TNBC patients and selected 13 CRGs for constructing the prognostic model. Kaplan-Meier survival curves, time-dependent receiver operating characteristic curves, and other analyses confirmed that TNBC patients with high CRRS had shorter overall survival, and the predictive ability of CRRS prognostic model was further validated using the GEO dataset. Nomogram combining clinical features confirmed that CRRS was an independent factor for the prognosis of TNBC patients. Moreover, patients in the high-risk group had lower levels of immune infiltration in the TME and were sensitive to chemotherapeutic drugs such as 5-fluorouracil, ipatasertib, and paclitaxel. ConclusionWe have developed a CRRS-based prognostic model composed of 13 differentially expressed CRGs, which may serve as a useful tool for predicting the prognosis of TNBC patients and guiding clinical treatment. Moreover, the key genes within this model may represent potential molecular targets for future therapies of TNBC.

Objective Hypertriglyceridemic waist(HW),hypertriglyceridemic waist-to-height ratio(HWHtR),and waist-to-hip ratio(WHR)have been shown to be indicators of cardiometabolic risk factors.However,it is not clear which indicator is more suitable for children and adolescents.We aimed to investigate the relationship between HW,HWHtR,WHR,and cardiovascular risk factors clustering to determine the best screening tools for cardiometabolic risk in children and adolescents. Methods This was a national cross-sectional study.Anthropometric and biochemical variables were assessed in approximately 70,000 participants aged 6-18 years from seven provinces in China.Demographics,physical activity,dietary intake,and family history of chronic diseases were obtained through questionnaires.ANOVA,x2 and logistic regression analysis was conducted. Results A significant sex difference was observed for HWHtR and WHR,but not for HW phenotype.The risk of cardiometabolic health risk factor clustering with HW phenotype or the HWHtR phenotype was significantly higher than that with the non-HW or non-HWHtR phenotypes among children and adolescents(HW:OR = 12.22,95%CI:9.54-15.67;HWHtR:OR = 9.70,95%CI:6.93-13.58).Compared with the HW and HWHtR phenotypes,the association between risk of cardiometabolic health risk factors(CHRF)clustering and high WHR was much weaker and not significant(WHR:OR = 1.14,95%CI:0.97-1.34). Conclusion Compared with HWHtR and WHR,the HW phenotype is a more convenient indicator with higher applicability to screen children and adolescents for cardiovascular risk factors.