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Background The heterogeneity of myelodysplastic syndromes (MDS) is strong, with poor efficacy of existing therapeutic regimens and large individual differences in patient prognosis. B-cell lymphomato-2 (Bcl-2) protein is highly expressed in patients with myeloid tumors, which has been proved by previous to be associated with disease progression, chemotherapy resistance, and shortened overall survival. The Bcl-2 inhibitor Veneckla (VEN) is approved for elderly patients with newly diagnosed acute myeloid leukemia (AML) who are not eligible for intensive therapy, and there is less data on its use in MDS patients. The difference in Bcl-2 expression in MDS patients and its correlation with the efficacy and prognosis of VEN therapy haven't been reported. Objective To analyse the expression of Bcl-2 protein in MDS patients and assess its correlation with the efficacy and prognosis of VEN treatment. Methods The clinical data of 71 patients with MDS admitted to Sichuan Academy of Medical Sciences·Sichuan Provincial People's Hospital from July 2018 to December 2022 were retrospectively analyzed. Baseline data of patients including gender, age, blood routine, blood biochemistry, bone marrow hemocytology, flow cytometry, chromosome karyotype, myeloid gene mutation, fusion gene mutation and MDS-EB typing were collected. The expression of Bcl-2 protein was detected by immunohistochemical staining. According to the modified International Prognostic Score System (IPSS-R), the patients were divided into 5 risk levels of very low risk (0 case), low risk (1 case), medium risk (7 cases), high risk (40 cases) and very high risk (23 cases). Patients with bone marrow Bcl-2 positivity≥10% were defined as Bcl-2 positive and0.05) . Conclusion Bcl-2 protein contributes to MDS fusion gene mutation and myeloid gene mutation; Bcl-2 positive expression was not associated with the survival of MDS patients. There was no difference in survival rate between Bcl-2 positive and Bcl-2 negative patients who received the VA combination regimen.

With the increase in ambient temperature around the world in summer, the working environment of cable joints is deteriorating. Based on the finite element method, a simulation model for temperature analysis in a 10 kV three-core cable and the joints is established. The temperature distribution is analyzed under different ambient temperatures and different currents. Firstly, the temperature rise experiments are carried out to obtain a steady temperature on the surface of the cable joint, which verifies the accuracy of the simulation model. Then, the relationships between the surface temperature and the current of the high voltage current carrying conductor of the joint under different ambient temperatures are fitted. The ultimate safe current carrying capacity of the joint under the different ambient temperatures can be calculated by using these related functions. The results show that the increase of ambient temperature has little effect on the temperature distribution trend of the high voltage conductor surface of the joint, which also meets this rule on the outer surface of the outer sheath. The relation of the surface temperature on the high voltage conductor of the joint to the current is approximately a quadratic function. When the current amplitude is 480 A and the ambient temperature is 75 ℃, the highest temperatures on the surface of the high-voltage current-carrying conductor and the outer surface of the outer sheath are 1.57 and 1.69 times higher respectively than at an ambient temperature of 30 ℃. When the ambient temperature exceeds 55 ℃, the continuous allowable current carrying capacity specified in the national standard can make the high voltage copper conductor of the joint exceed the maximum permitted operating temperature of 90 ℃. Considering the continuous increase in summer ambient temperature since 2020, the continuous allowable current carrying capacity of the intermediate joint of 10 kV copper conductor three-core cross-linked polyethylene insulated cables in the GB needs to be improved and perfected.

Background Multiple myeloma (MM) is a common hematologic malignancy. With the emergence of a variety of new drugs, the survival rates of patients have increased, however, further discussion on how to achieve deeper and faster remission and reduce recurrence of patients is still needed. Objective To investigate the efficacy and safety of daratumumab in the chemotherapy of MM. Methods 73 MM patients treated with daletumab in Sichuan Provincial People's Hospital from January 2020 to July 2022 were included as study subjects. Baseline information of the included patients were collected through the electronic medical record system. All patients were treated with daletumab based regimen and followed up through outpatient and inpatient review and telephone once a month when it is not time for review, with the time of first use of darettuzumab since 2020-01-01 as the starting point, death, disease recurrence or end of follow-up as the ending point. Follow-up was up to 2022-07-31 with a median follow-up time of 6.5 (0.5, 26.5) months. Overall response rate (ORR) and complete response rate were used to evaluate the efficacy of the patients. Kaplan-Meier curves were plotted for different drug use, initial renal function, drug administration, cytogenetic risk stratification and M protein types, and compared by Log-rank test. Results The median age of the patients was 64 (30, 86) years, including 38 males and 35 females. 28 MM patients were treated with first-line darettuzumab, 13 were switched from other regiments to darettuzumab due to adverse reactions, and 32 patients had relapsed and refractory multiple myeloma (RRMM). 18 patients were lost during follow-up, and a total of 55 patients were available for efficacy assessment. After one course of treatment with the darettuzumab-based chemotherapy regimen, ORR was 72.7% with the complete response rate of 30.9%, including 3.6% (2/55) achieved strin-gent complete response (sCR) and 27.3% (15/55) achieved complete response (CR), 10.9% (6/55) achieved very good partial response (VGPR), 30.9% (17/55) achieved partial response (PR), 9.1% (5/55) achieved minimal response (MR), 12.7% (7/55) achieved stable disease (SD), and 5.5% (3/55) achieved disease progression (PD). The median progress free survival (PFS) of the patients was 6.0 (0.5, 26.5) months, and the median overall survival was 16 (3, 103) months. There was no statistically significant difference in the PFS survival curve between patients treated first-line with darettuzumab and RRMM patients (χ2=3.676, P=0.055). The difference of PFS survival curve between patients with normal and impaired renal function was statistically significant (χ2=12.51, P=0.004). There was a statistically significant difference in the survival curve of patients treated with daletumab + bortezomib + dexamethasone and those treated with daletumab + dexamethasone (χ2=6.691, P=0.009). There was no statistically significant difference in PFS survival curves between patients with non-high risk and high-risk cytogenetic classification (χ2=0.328, P=0.567). There was no statistically significant difference in PFS survival curves among patients with M protein types of IgA, IgG, IgD, light chain, double clone and non-secretory (P>0.05). The main adverse reactions of the patients were infusion reaction and myelosuppression, of which 21 patients had adverse infusion reactions at the first infusion, 21 patients had leukopenia, 40 patients had anemia and 16 patients had thrombocytopenia. Conclusion Darettuzumab has good curative effect in MM patients, which can be used as the first-line treatment for newly diagnosed patients, improve the clinical prognosis of RRMM patients, and prolong the survival time of patients.