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.

Inflammatory response,immunosuppression,and drug sensitivity have been reported to have a significant correlation with the disulfidptosis levels in cancer patients.However,the value of disulfidpto-sis in colorectal cancer therapy remains unclear.Therefore,we classified the CRC cells into different cell types using single-cell sequencing data and cell-specific markers and analyzed their relationship with the cell disulfidptosis level.We found that the high disulfidptosis regions were concentrated in epithelial-like CRC cells.Further exploration using the disulfidptosis and programmed cell death 1 inhibitor therapy treated differential expression genes indicated that CRC patients with high disulfidptosis levels exhibited a lower risk profile and increased sensitivity to immunotherapy.By using the spatial transcriptomic analy-sis,we found that ubiquinol-cytochrome c reductase core protein 1(UQCRC1),a disulfidptosis-related gene,is highly expressed in epithelial-like CRC cells and co-localized with immune-infiltrated tumor re-gions.Additional bioinformatic analyses and experimental validation further confirmed that UQCRC1 was downregulated in CRC tissues.Overexpression of UQCRC1 suppressed CRC cell proliferation and migra-tion.These findings indicate that UQCRC1 is a potential target for CRC diagnosis and treatment.

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.

Inflammatory response,immunosuppression,and drug sensitivity have been reported to have a significant correlation with the disulfidptosis levels in cancer patients.However,the value of disulfidpto-sis in colorectal cancer therapy remains unclear.Therefore,we classified the CRC cells into different cell types using single-cell sequencing data and cell-specific markers and analyzed their relationship with the cell disulfidptosis level.We found that the high disulfidptosis regions were concentrated in epithelial-like CRC cells.Further exploration using the disulfidptosis and programmed cell death 1 inhibitor therapy treated differential expression genes indicated that CRC patients with high disulfidptosis levels exhibited a lower risk profile and increased sensitivity to immunotherapy.By using the spatial transcriptomic analy-sis,we found that ubiquinol-cytochrome c reductase core protein 1(UQCRC1),a disulfidptosis-related gene,is highly expressed in epithelial-like CRC cells and co-localized with immune-infiltrated tumor re-gions.Additional bioinformatic analyses and experimental validation further confirmed that UQCRC1 was downregulated in CRC tissues.Overexpression of UQCRC1 suppressed CRC cell proliferation and migra-tion.These findings indicate that UQCRC1 is a potential target for CRC diagnosis and treatment.

Objective:To analyze the effect of high serum ferritin(SF)before transplantation on erythrocyte,granulocyte and platelet implantation in unrelated cord blood transplantation(UCBT)patients with myelodysplastic syndrome(MDS)and acute myeloid leukemia(AML).Methods:The medical records of 60 patients with MDS and AML who underwent UCBT in the First Affiliated Hospital of University of Science and Technology of China from January 2020 to December 2022 were retrospectively collected.According to the SF level before transplantation,they were divided into high SF group(SF ≥ 1 000 μg/L,n=20)and non-high SF group(SF＜1 000 μg/L,n=40).The red blood cell(RBC)infusion volume before transplantation,implantation time of RBC,granulocyte and platelet,implantation risk and prognosis were analyzed and compared between the two groups.Results:There was no correlation between the level of SF before transplantation and RBC infusion.After transplantation,the median implantation time of RBC in the high SF group was 28.5(14-149)d,which was longer than 21(10-83)d in the non-high SF group(P＜0.05).The median time of granulocyte engraftment in the high SF group was 16.5(12-63)d,while that in the non-high SF group was 16(12-49)d,with no statistical difference between the two groups(P＞0.05).The median platelet engraftment time in the high SF group was 45(12-206)d,while that in the non-high SF group was 35.5(14-149)d,with no statistical difference between the two groups(P＞0.05).Kaplan-Meier cumulative implantation probability analysis showed that the rate of erythroid implantation in the non-high SF group was higher than that in the high SF group(P＜0.05),while there was no significant difference in the rates of granulocyte and platelet implantation between the two groups(P＞0.05).The 1-year overall survival rates of the non-high SF group and high SF group were 95％and 90％,respectively,with no statistical difference between the two groups(P＞0.05).Conclusion:SF levels before cord blood transplantation in MDS and AML patients have an impact on post transplant erythroid implantation.Detecting and intervening of iron load in patients before transplant may be beneficial for improving implantation and prognosis.

Objective To explore and establish the bacterial endotoxin limit value and testing method of the active pharmaceutical ingredient （API） of pentetic acid, and conduct methodological investigation. Methods Three batches of pentetic acid were used to establish the method for the determination of bacterial endotoxin, and interference test was conducted simultaneously. The sample was dissolved with commercially available alkaline regulator to a concentration of 4 mg/ml or lower, and then diluted with water for bacterial endotoxin test. Limulus reagent with sensitivity of 0.125 EU/ml or higher was selected and redissolved with commercially available magnesium ion buffer solution. And the endotoxin test was performed by gel method. Results The endotoxin limit of API of pentetic acid was determined as: less than 0.125 EU/mg. Conclusion The method established could be used for the control of bacterial endotoxin in API of pentetic acid.

OBJECTIVE: To analyze the RHD genotyping and sequencing results of RhD serology negative samples in the clinic, and to further explore the laboratory methods for RhD detection, in order to provide a basis for clinical precision blood transfusion. METHODS: A total of 27 200 whole blood samples were screened for RhD blood group antigen using microcolumn gel card method.Serologic RhD-negative confirmation tests were performed on blood samples that were negative for RhD on initial screening using three different clonal strains of IgG anti-D reagents. The 10 exons of the RHD gene on chromosome 1 were also analyzed by PCR-SSP to determine RHD genotyping.When the PCR-SSP method did not yield definitive results, the RHD gene of the sample was analyzed by the third-generation sequencing. RESULTS: The results of the initial screening test by the microcolumn gel card method showed that 136 of the 27 200 samples were RhD-negative, of which 86 underwent RhD-negative confirmation testing and RHD genotyping, 88.37% (76/86 cases) of the RhD-negative confirmation test results were negative for the three anti-D reagents, and the results of RHD genotyping showed that 67.44% (58/86 cases) of the cases had a complete deletion of 10 exons, and the remaining 28 cases were RHD*711delC (1 case), RHD*D-CE(1-9)-D (1 case), RHD*D-CE(2-9-)D (2 cases), RHD*D-CE(3-9)-D (4 cases), RHD*DEL1 (c.1227G >A) mutation (16 cases), RHD*weak partial 15(845G >A) mutation (3 cases), and a mutation of c.165C >T base was found in 1 sample by three-generation sequencing. CONCLUSION RHD genotype testing of samples that are serologically negative for RhD antigen shows that some of the samples have RHD gene variants, not all of which are total deletions of RHD, suggesting that there are some limitations of the serologic method for RhD detection. Due to the polymorphism of the RHD gene structure, different RhD variants present different serologic features, which need to be further detected in combination with molecular biology testing, especially for the identification of Asian-type DELs, which is important for clinical precision blood transfusion.
Humans ; Rh-Hr Blood-Group System/genetics* ; Genotype ; Polymerase Chain Reaction ; Exons ; Blood Grouping and Crossmatching

Objective:To analyze the effect of high serum ferritin(SF)before transplantation on erythrocyte,granulocyte and platelet implantation in unrelated cord blood transplantation(UCBT)patients with myelodysplastic syndrome(MDS)and acute myeloid leukemia(AML).Methods:The medical records of 60 patients with MDS and AML who underwent UCBT in the First Affiliated Hospital of University of Science and Technology of China from January 2020 to December 2022 were retrospectively collected.According to the SF level before transplantation,they were divided into high SF group(SF ≥ 1 000 μg/L,n=20)and non-high SF group(SF＜1 000 μg/L,n=40).The red blood cell(RBC)infusion volume before transplantation,implantation time of RBC,granulocyte and platelet,implantation risk and prognosis were analyzed and compared between the two groups.Results:There was no correlation between the level of SF before transplantation and RBC infusion.After transplantation,the median implantation time of RBC in the high SF group was 28.5(14-149)d,which was longer than 21(10-83)d in the non-high SF group(P＜0.05).The median time of granulocyte engraftment in the high SF group was 16.5(12-63)d,while that in the non-high SF group was 16(12-49)d,with no statistical difference between the two groups(P＞0.05).The median platelet engraftment time in the high SF group was 45(12-206)d,while that in the non-high SF group was 35.5(14-149)d,with no statistical difference between the two groups(P＞0.05).Kaplan-Meier cumulative implantation probability analysis showed that the rate of erythroid implantation in the non-high SF group was higher than that in the high SF group(P＜0.05),while there was no significant difference in the rates of granulocyte and platelet implantation between the two groups(P＞0.05).The 1-year overall survival rates of the non-high SF group and high SF group were 95％and 90％,respectively,with no statistical difference between the two groups(P＞0.05).Conclusion:SF levels before cord blood transplantation in MDS and AML patients have an impact on post transplant erythroid implantation.Detecting and intervening of iron load in patients before transplant may be beneficial for improving implantation and prognosis.

Objective:To evaluate the effect of individualized positive end-expiratory pressure (PEEP) titration based on open-lung strategy on the intraoperative thoracic fluid content (TFC) in elderly patients undergoing transurethral ultrasound-guided laser-induced prostatectomy (TULIP).Methods:Eighty-six American Society of Anesthesiologists Physical Status classification Ⅱ or Ⅲ, patients, aged 65-80 yr, with body mass index of 18-28 kg/m 2, scheduled for elective TULIP, were divided into 2 groups ( n=43 each) by the random number table method: fixed PEEP group (group C) and individualized PEEP titration group (group P). PEEP was set at 4 cmH 2O after routine mechanical ventilation in group C. Patients underwent pulmonary recruitment maneuvers combined with individualized PEEP titration during surgery in group P. TFC was measured using a non-invasive cardiac output monitor at 5 min after tracheal intubation (T 0), 30 min after PEEP titration and ventilation (T 1), 5 min before surgery (T 2), and 5 min before leaving the recovery room (T 3). Cardiac output, oxygenation index and stroke volume index were recorded from T 0-T 2, arterial blood gas analysis was simultaneously performed to record peak airway pressure and dynamic lung compliance, and oxygenation index was calculated. The duration of postanesthesia care unit stay, pulmonary complications within 7 days after surgery, and length of hospital stay were also recorded. Results:Eighty-three patients were finally included, with 42 in group C and 41 in group P. Compared with group C, TFC was significantly decreased at T 1-T 3, cardiac index, cardiac output and stroke volume index were decreased at T 1, dynamic lung compliance, PaO 2 and oxygenation index were increased at T 1 and T 2, PaCO 2 was decreased, the incidence of postoperative pulmonary complications was reduced, and the duration of postanesthesia care unit stay and postoperative length of hospital stay were shortened in group P ( P<0.05). Conclusions:Individualized PEEP titration based on open-lung strategy can effectively decrease TFC and improve intraoperative oxygenation and prognosis in elderly patients undergoing TULIP.