Kv1.3,a voltage-gated potassium channel,is highly expressed in T lymphocytes,the nervous system,and vascular smooth muscle cells.It plays a critical role in membrane excitability and electrical signal transduction,serving as an important target for studying T-cell function and providing a promising direction for developing therapeutics against autoimmune and inflammatory diseases.Therefore,the de-velopment of specific inhibitors of Kv1.3 channel has emerged as a novel therapeutic strategy for these disorders.In this study,we isolated and purified a novel Kv1.3-inhibitory peptide toxin,LmKTx13,from the venom of the scorpion Lychas mucronatus using reversed-phase high-performance liquid chroma-tography(RP-HPLC).LmKTx13 consists of 38 amino acid residues,including six cysteines that form three disulfide bonds.Whole-cell patch-clamp recordings revealed that LmKTx13 potently inhibited Kv1.3 with an IC50 of 7.92±3.0 nmol/L.Selectivity analysis showed that 2 μmol/L LmKTx13 also in-hibited Kv1.2 and Kv1.7,but exhibited no significant effects on other potassium channel subtypes or voltage-gated sodium channels.Further investigation into the mechanism demonstrated that LmKTx13 acts as a pore-blocking inhibitor of Kv1.3.By analyzing the effects of LmKTx13 on Kv1.3 channel gating ki-netics and performing sequence alignment of the pore regions of Kv1.3 and Kv1.5,we constructed site-directed mutants and identified the pore region of Kv1.3 as the critical binding site for LmKTx13.Key residues involved in the interaction included T425,G427,and H451.In summary,we discovered a no-vel pore-blocking Kv1.3 inhibitor,LmKTx13,from L.mucronatus venom,which exhibits high affinity and selectivity for Kv1.3.These findings highlight its potential as a potential lead molecule for developing Kv1.3-targeted therapeutics.

Kv1.3,a voltage-gated potassium channel,is highly expressed in T lymphocytes,the nervous system,and vascular smooth muscle cells.It plays a critical role in membrane excitability and electrical signal transduction,serving as an important target for studying T-cell function and providing a promising direction for developing therapeutics against autoimmune and inflammatory diseases.Therefore,the de-velopment of specific inhibitors of Kv1.3 channel has emerged as a novel therapeutic strategy for these disorders.In this study,we isolated and purified a novel Kv1.3-inhibitory peptide toxin,LmKTx13,from the venom of the scorpion Lychas mucronatus using reversed-phase high-performance liquid chroma-tography(RP-HPLC).LmKTx13 consists of 38 amino acid residues,including six cysteines that form three disulfide bonds.Whole-cell patch-clamp recordings revealed that LmKTx13 potently inhibited Kv1.3 with an IC50 of 7.92±3.0 nmol/L.Selectivity analysis showed that 2 μmol/L LmKTx13 also in-hibited Kv1.2 and Kv1.7,but exhibited no significant effects on other potassium channel subtypes or voltage-gated sodium channels.Further investigation into the mechanism demonstrated that LmKTx13 acts as a pore-blocking inhibitor of Kv1.3.By analyzing the effects of LmKTx13 on Kv1.3 channel gating ki-netics and performing sequence alignment of the pore regions of Kv1.3 and Kv1.5,we constructed site-directed mutants and identified the pore region of Kv1.3 as the critical binding site for LmKTx13.Key residues involved in the interaction included T425,G427,and H451.In summary,we discovered a no-vel pore-blocking Kv1.3 inhibitor,LmKTx13,from L.mucronatus venom,which exhibits high affinity and selectivity for Kv1.3.These findings highlight its potential as a potential lead molecule for developing Kv1.3-targeted therapeutics.

Objective To observe the clinical efficacy of adjuvant PD-1 inhibitor in the treatment of patients with hepatocellular carcinoma after microwave ablation and the changes of lymphocyte subsets before and after treatment.Methods A total of 56 patients with hepatocellular carcinoma who underwent microwave ablation in our hospital were randomly divided into two groups according to different treatments,with 28 cases in each group.Patients in the group A received adjuvant treatment with PD-1 inhibitors after microwave ablation,while patients in the group B received microwave ablation alone.The local efficacy of microwave ablation,the survival of patients after adjuvant treatment of PD-1 inhibitor and the occurrence of related adverse reactions were observed.Peripheral venous blood was collected to detect the number of T lymphocyte subsets before microwave ablation in the two groups,after microwave ablation in the group B,and after six cycles of immunotherapy in the group A.Results There was no significant difference in the complete ablation rate of cases between group A and group B(89.3% vs.85.7%,P=0.69),and there was no significant difference in the complete ablation rate of lesions between group A and group B(91.7% vs.85.3%,P=0.40).The median progression-free survival(mPFS)of the group A was not yet reached,the mPFS of group B was 12.6 months,and there was a statistically significant difference in the mPFS between the two groups(P=0.03).The median overall survival(mOS)of the two group were not yet reached.The proportion of CD4+T lymphocytes after treatment in the group A significantly increased compared with that in the group B[(37.05±2.22)% vs.(29.23±2.88)%,P=0.03],while the proportion of CD8+T lymphocytes[(21.08±2.23)% vs.(27.18±1.75)%,P=0.04)]and the proportion of Treg cells[(4.26±0.31)% vs.(5.22±0.34)%,P=0.04]significantly decreased.There was no serious adverse reactions in all patients after microwave ablation,and 28 patients in the group A had no adverse reactions above grade 3 after PD-1 inhibitor treatment.Conclusion Adjuvant PD-1 inhibitor therapy after microwave ablation can prolong the progression-free survival of patients,enhance the function of T lymphocytes,and weaken the role of immunosuppressive cells,which may be an effective strategy to delay the recurrence of liver cancer after microwave ablation.

Objective: To investigate the protective effect and mechanism of Nicotinamide Riboside (NR) on lung injury caused by Paraquat intoxicated mice. Methods: Eighty clean male BALB/C mice were selected and averagely divided forty mice into 4 groups with 10 mice in each group, PQ group was given 25% PQ solution (60 mg/kg) by one-time gavage. PQ+NR group were intraperitoneally injected with NR solution (300 mg/kg) 1 hour before given the same amount of PQ solution (60 mg/kg) by one-time gavage, The Control group were given the same amount of saline by one-time gavage, The same amount of NR was intraperitoneally injected before NR group were given saline by one-time gavage. Observed and recorded general condition of PQ intoxicated mice. Observed and recorded the death of mice every half an hour and counted the mortality and drew survival curve of each group after 72 hours exposure. another forty mice were averagely divided and treated by the same way. After 24 hours of modelling, mice were anaesthetized and killed. Then blood was extracted after eyeball was removed. The changes of TNF-a、IL-6 and MPO in serum of mice were detected by ELISA.Two lung tissues were removed from the chest and used to measure the D/W ratio of the lung. The pathological changes of lung were observed and scored under light microscope.The levels of SOD, MDA and Caspase-3 in lung tissues were determined by chemical colorimetry. The expression of Sirt1 and Nrf2 in lung tissues was detected by Western-blot. Results: Compared with the Control group and the NR group, the mice in the PQ group had a poor general condition, such as depression, crouching, skin disorder and reduced activity, food, urine and feces. The symptoms in the PQ+NR group were reduced compared with the PQ group. The survival rate at 72 hours after exposure: 80% in the PQ+NR group and 40% higher than that in the PQ group (P=0.029) . Compared with Control group and NR group, the D/W ratio (0.09±0.07) , lung pathology score under light microscope (11.80±0.37) , TNF-a (39.89±1.48) pg/ml、IL-6 (77.29±2.38) pg/ml、MPO (0.31±0.01) μg/ml、SOD (6.62±0.30) U/mgprot、MDA level (1.21±0.14) mmol/mgprot, Caspase-3 activity (356.00± 27.16) %, Sirt1 and Nrf2 protein expression (1.02±0.14、0.82±0.06) were significantly decreased in PQ group (P=0.004、0.023) ; Compared with PQ group, PQ+NR group significantly increased the D/W ratio (0.10±0.10) , decreased the pulmonary pathology score under light microscope (7.400.51) , decreased TNF-a (33.00± 0.65) pg/ml、IL-6 (52.23±4.23) pg/ml、MPO leve (0.23±0.01) μg/mll, increased SOD leve (9.28±0.45) U/mgprotl, decreased MDA level (0.78±0.02) mmol/mgprot, decreased Caspase-3 activity (222.80±7.59) %, and increased the protein expressions of Sirt1 and Nrf2 (1.62±0.16、1.06±0.04) (P=0.048、0.035) . Conclusion: NR can prolong the survival time of PQ poisoned mice; NR intervention can effectively inhibit the inflammatory response, peroxidation injury and apoptosis of PQ poisoned mice; NR intervention can upregulate the expression of Sirt1 and Nrf2 protein and effectively reduce the lung injury of PQ poisoning.
Animals ; Caspase 3/metabolism* ; Interleukin-6/metabolism* ; Lung ; Lung Injury/metabolism* ; Male ; Mice ; Mice, Inbred BALB C ; NF-E2-Related Factor 2/metabolism* ; Niacinamide/pharmacology* ; Paraquat/toxicity* ; Pyridinium Compounds/pharmacology* ; Sirtuin 1/metabolism* ; Superoxide Dismutase/metabolism*

Objective:To preliminarily estimate and study the effect of nucleic acid testing in blood screening on the residual risk (RR) of transfusion transmitted HBV infection (TTI HBV).Methods:Using the NAT yield/WP ratio model and adopting the relevant data of information management system of practice comparison working party in the Mainland of China, this paper analyzed the trend of the RR of TTI HBV among 18 blood centers from 2015 to 2019 in China, and compared the impact of two kinds of blood screening strategies which were ELISA+ ID-NAT/MP-NAT (individual-donation nucleic acid testing or mini-pool nucleic acid testing) and ELISA + MP-NAT on RR in 2019.Results:The overall trends of the 5-year RR of HBV among 18 blood centers showed by trend chi square test were NAT single positive rate trend χ2= 39.42( P<0.01) and residual risk trend χ2= 279.792( P<0.01); The influence on RR from the differences of ELISA+ ID-NAT/MP-NAT and ELISA+ MP-NAT was statistically significant, and chi square test showed that χ2= 7.4( P<0.01). Conclusions:Since the implementation of nucleic acid testing in the blood screening in China from 2015, the residual risk of transfusion transmitted HBV infection has decreased year by year. The observed two blood screening strategies which dominated in China may lead to discrepancy in the residual risk of TTI.

To investigate the effects of exogenous NaHS on myelin basic protein (MBP) and learning and memory of hippocampal neurons in mice with spinocerebellar ataxia type 3 (SCA3) and its therapeutic significance. Twelve male normal mice were randomly selected as normal control group (NC Group), and 48 SCA3 mice were randomly selected as SCA3 model group (M Group), low dose group (NL Group, 10 μmol/kg), medium dose group (NM Group, 50μmol/kg) and high dose group (NH Group, 100 μmol/kg), 12 rats in each group. The drug treated groups were injected with NaHS intraperitoneally once a day for 4 weeks. The changes of learning and memory ability of SCA3 mice before and after the intervention of different doses of NaHS were determined by Morris water maze, the content of hydrogen sulfide (HS) in hippocampus was measured by spectrophotometry, the expression of MBP was detected by immunohistochemistry, and the morphological changes of neuron myelin sheath were observed by electron microscope. Compared with the control group, the learning and memory ability of SCA3 mice was decreased significantly (P＜0.05), and the content of HS in hippocampus was decreased (P＜0.05). After different doses of exogenous NaHS treatment, the learning and memory ability was improved in different degrees (P＜0.05), and the contents of HS and MBP in hippocampus of SCA3 mice were also improved in different degrees (P＜0.05). Exogenous NaHS may increase the contents of HS and MBP in the hippocampus of SCA3 mice, which may have a protective effect on the neurons, and then improve the learning and memory ability of SCA3 mice, and provide a new idea for the treatment of SCA3.

Since December 2019, increasing attention has been paid to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epidemic in Wuhan, China. SARS-CoV-2 primarily invades the respiratory tract and lungs, leading to pneumonia and other systemic disorders. The effect of SARS-CoV-2 in transplant recipients has raised significant concerns, especially because there is a large population of transplant recipients in China. Based on the current epidemic situation, this study reviewed publications on this virus and coronavirus disease 2019 (COVID-19), analyzed common features of respiratory viral pneumonias, and presented the currently reported clinical characteristics of COVID-19 in transplant recipients to improve strategies regarding the diagnosis and treatment of COVID-19 in this special population.

Since December 2019, increasing attention has been paid to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epidemic in Wuhan, China. SARS-CoV-2 primarily invades the respiratory tract and lungs, leading to pneumonia and other systemic disorders. The effect of SARS-CoV-2 in transplant recipients has raised significant concerns, especially because there is a large population of transplant recipients in China. Based on the current epidemic situation, this study reviewed publications on this virus and coronavirus disease 2019 (COVID-19), analyzed common features of respiratory viral pneumonias, and presented the currently reported clinical characteristics of COVID-19 in transplant recipients to improve strategies regarding the diagnosis and treatment of COVID-19 in this special population.

OBJECTIVETo assess the performance of a minimally invasive thoracic drainage tube (14 F) made of polyurethane (PU) in a rabbit model of hemothorax in comparison with the conventional 28 F chest tube (CCT).

METHODSThirty New Zealand rabbits were divided into experimental chest tube (ECT) group (n=9), CCT group (n=6), and blood provider group (n=15). Blood samples (20 mL) collected from the blood providing rabbits were injected into the chest cavity of the rabbits in the other two groups, and the time taken for closed drainage of the thoracic cavity was recorded. The rabbits in ECT and CCT groups were subjected to blood injections (20 mL for each injection) into the chest cavity every 20 min for 5 times, and the volumes of blood drained by ECT and CCT were measured. Two hours later, the rabbits were sacrificed and the residual blood and blood clots in the chest cavities were observed.

RESULTSCompared with CCT, the use of ECT significantly shortened the operation time (P<0.05) and produced more effective blood drainage at 20 min and 40 min after the placement of the drainage tube (P<0.05). No significant difference was found in the total blood volume drained between ECT and CCT groups, but the volume of residual blood in the thoracic cavity was significantly smaller in ECT group than in CCT group. No post-operative complications were found in the rabbits in ECT group while all the rabbits in CCT group had abutment pressure to the lung.

CONCLUSIONCompared to CCT, ECT is less invasive and allows more effective thoracic drainage with more convenient operation and reduced postoperative complications, suggesting its potential for use in closed thoracic drainage in single-port video-assisted thoracoscopic surgery (VATS) or in pediatric patients.

BACKGROUND:Studies have shown that bioactive molecules or polypeptides grafted onto the surface of polyethylene glycol (PEG) hydrogels can improve PEG bioactivities.OBJECTIVE:To manufacture PEG hydrogels capable of auto-recruiting growth factor beta1 (TGF-β1) and to study its biocompatibility. METHODS:Pure PEG hydrogels (group A), PEG hydrogels grafted on a cell adhesion peptide RGD peptides (group B), PEG hydrogels grafted with auto-recruited TGF-β1 peptide sensitive polypeptide HSNGLPL (group C), PEG hydrogels grafted with both RGD and HSNGLPL polypeptides (group D) were prepared. Contract angle of the hydrogel was detected in each group. Human bone mesenchymal stem cells were seeded onto four kinds of hydrogels. After cells attached, scanning electron microscope and LIVE/DEAD staining were done to observe cell-hydrogel compounds. Human bone marrow mesenchymal stem cells were co-cultured with ordinary culture medium (control) or four kinds of hydrogels for 1, 3, 5, 7 days, and the cell proliferation was detected by cell counting kit-8 assay. The four kinds of hydrogels were put into 24-well culture plates with addition of PBS containing TGF-β1, and 1 hour later, immunofluorescence staining was done. RESULTS AND CONCLUSION:(1) The contact angles of groups A and C were larger than those of groups B and D. (2) Under the scanning electron microscope, groups A and C had little cells attached on the hydrogel surface, but there were many cells on the hydrogel surface in groups B and D. (3) LIVE/DEAD staining showed groups A and C had little living cells, and conversely groups B and D had many living cells. (4) The results of cell counting kit-8 demonstrated that as the incubation time went on, cell proliferation activity of five different groups increased with no difference at the same time point. (5) Findings from the immunofluorescence staining showed that groups A and B had very weak fluorescence, while groups C and D had stronger green fluorescence. In conclusion, PEG hydrogels grafted with RGD and HSNGLPL polypeptides can auto-recruit TGF-β1, and have good biocompatibility.