In-depth study of the components of polymyxins is the key to controlling the quality of this class of antibiotics. Similarities and variations of components present significant analytical challenges. A two-dimensional (2D) liquid chromatography-mass spectrometr (LC-MS) method was established for screening and comprehensive profiling of compositions of the antibiotic colistimethate sodium (CMS). A high concentration of phosphate buffer mobile phase was used in the first-dimensional LC system to get the components well separated. For efficient and high-accuracy screening of CMS, a targeted method based on a self-constructed high resolution (HR) mass spectrum database of CMS components was established. The database was built based on the commercial MassHunter Personal Compound Database and Library (PCDL) software and its accuracy of the compound matching result was verified with six known components before being applied to genuine sample screening. On this basis, the unknown peaks in the CMS chromatograms were deduced and assigned. The molecular formula, group composition, and origins of a total of 99 compounds, of which the combined area percentage accounted for more than 95% of CMS components, were deduced by this 2D-LC-MS method combined with the MassHunter PCDL. This profiling method was highly efficient and could distinguish hundreds of components within 3 h, providing reliable results for quality control of this kind of complex drugs.

Objective:To analyze the clinical phenotype, sperm morphological characteristics and assisted reproductive therapy efficiency in patients with total globozoospermia.Methods:Four male patients with total globozoospermia were collected during November 2019 to May 2022 from Reproductive Medical and Genetic Center, the People's Hospital of Guangxi Zhuang Autonomous Region. Peripheral blood samples were collected for genetic detection and the whole exome sequencing to explore the pathogenic genes. Semen characteristics, sperm morphology and ultrastructure were analyzed. Four patients were treated with intracytoplasmic sperm injection (ICSI) combined with artificial oocyte activation (AOA). Conventional ICSI cycles ( n=9) were selected as control group, and the development dynamic parameters were monitored by Time-lapse. The fertilization and embryo development parameters, developmental dynamic parameters and clinical outcomes were analyzed between the two groups. Results:Four patients were complicated with low sperm motility and increased sperm DNA fragmentation. Sperm morphology analysis and acrosome fluorescence staining represented that all the spermatozoas were with a small round head lacked of acrosome. By the transmission electron microscope, it was observed that round-headed spermatozoas were lacked of acrosome completely, loose chromatin structure, vacuolation and other abnormal changes in the head, mitochondrial sheath in neck were reduced arranged in disorder, and the structure of "9+2" of the flagellar axial filament was incomplete. Of the 4 patients, 1 was homozygous deletion of DPY19L2 gene and 1 was homozygous frameshift mutation of DPY19L2 gene. There were no significance differences in fertilization rate, two pronuclei fertilization rate, day 3 high-quality embryo rate, day 6 blastocyst formation rate and day 6 high-quality blastocyst formation rate between total globozoospermia group and control group (all P>0.05). The developmental dynamic parameters as the time at which the second polar body is extruded, the time when both (or the last) PN disappear, two to six discrete cells in the total globozoospermia group were significantly earlier than those in control group, and the difference was statistically significant (all P<0.05). There was no significant difference in the embryo cleavage patterns between the two groups ( P>0.05). Among the 4 patients with total globozoospermia, 2 live births with signal healthy male baby were achieved by fresh embryo transfer, and 2 live births with one signal healthy male baby and one healthy female baby were achieved by frozen-thawed embryo transfer respectively. Conclusion:Abnormal morphology characteristics of spermatozoas from patients with total globozoospermia are obvious, patients with total globozoospermia could have favorable clinical outcomes following ICSI combined with AOA.

Objective:To analyze the clinical phenotype, sperm morphological characteristics and assisted reproductive therapy efficiency in patients with total globozoospermia.Methods:Four male patients with total globozoospermia were collected during November 2019 to May 2022 from Reproductive Medical and Genetic Center, the People's Hospital of Guangxi Zhuang Autonomous Region. Peripheral blood samples were collected for genetic detection and the whole exome sequencing to explore the pathogenic genes. Semen characteristics, sperm morphology and ultrastructure were analyzed. Four patients were treated with intracytoplasmic sperm injection (ICSI) combined with artificial oocyte activation (AOA). Conventional ICSI cycles ( n=9) were selected as control group, and the development dynamic parameters were monitored by Time-lapse. The fertilization and embryo development parameters, developmental dynamic parameters and clinical outcomes were analyzed between the two groups. Results:Four patients were complicated with low sperm motility and increased sperm DNA fragmentation. Sperm morphology analysis and acrosome fluorescence staining represented that all the spermatozoas were with a small round head lacked of acrosome. By the transmission electron microscope, it was observed that round-headed spermatozoas were lacked of acrosome completely, loose chromatin structure, vacuolation and other abnormal changes in the head, mitochondrial sheath in neck were reduced arranged in disorder, and the structure of "9+2" of the flagellar axial filament was incomplete. Of the 4 patients, 1 was homozygous deletion of DPY19L2 gene and 1 was homozygous frameshift mutation of DPY19L2 gene. There were no significance differences in fertilization rate, two pronuclei fertilization rate, day 3 high-quality embryo rate, day 6 blastocyst formation rate and day 6 high-quality blastocyst formation rate between total globozoospermia group and control group (all P>0.05). The developmental dynamic parameters as the time at which the second polar body is extruded, the time when both (or the last) PN disappear, two to six discrete cells in the total globozoospermia group were significantly earlier than those in control group, and the difference was statistically significant (all P<0.05). There was no significant difference in the embryo cleavage patterns between the two groups ( P>0.05). Among the 4 patients with total globozoospermia, 2 live births with signal healthy male baby were achieved by fresh embryo transfer, and 2 live births with one signal healthy male baby and one healthy female baby were achieved by frozen-thawed embryo transfer respectively. Conclusion:Abnormal morphology characteristics of spermatozoas from patients with total globozoospermia are obvious, patients with total globozoospermia could have favorable clinical outcomes following ICSI combined with AOA.

Objective     To identify the heart sounds of aortic stenosis by deep learning model based on DenseNet121 architecture, and to explore its application potential in clinical screening aortic stenosis. Methods      We prospectively collected heart sounds and clinical data of  patients with aortic stenosis in Tianjin Chest Hospital, from June 2021 to February 2022. The collected heart sound data were used to train, verify and test a deep learning model. We evaluated the performance of the model by drawing receiver operating characteristic curve and precision-recall curve.  Results     A total of 100 patients including 11 asymptomatic patients were included. There were 50 aortic stenosis patients with 30 males and 20 females at an average age of 68.18±10.63 years in an aortic stenosis group (stenosis group). And 50 patients without aortic valve disease were in a negative group, including 26 males and 24 females at an average age of 45.98±12.51 years. The model had an excellent ability to distinguish heart sound data collected from patients with aortic stenosis in clinical settings: accuracy at 91.67%, sensitivity at 90.00%, specificity at 92.50%, and area under receiver operating characteristic curve was 0.917.   Conclusion     The model of heart sound diagnosis of aortic stenosis based on deep learning has excellent application prospects in clinical screening, which can provide a new idea for the early identification of patients with aortic stenosis.

Objective:To establish a technical system for early judgment and rescue artificial oocyte activation of oocytes after fertilization failed, intracytoplasmic sperm injection (ICSI) and to explore the activation efficiency and application value.Methods:Firstly, a retrospective analysis was performed in 150 ICSI cycles cultured by Time-lapse system during January 2017 to March 2018 from Reproductive Medical and Genetic Center, the People's Hospital of Guangxi Zhuang Autonomous Region, the time distribution of the second polar body (Pb2) exclusion and its relationship with fertilization and embryo development outcomes, the feasibility of Pb2 exclusion as an early indicator of fertilization failure in ICSI was discussed. Secondly, 225 fertilization failed oocytes from 93 ICSI cycles during March 2018 to June 2019 were collected for randomized controlled trials according to different artificial activation modes. They were divided into three groups including non-activation group (NAOA group), rescue activation group (RAOA group) and late activation group (LAOA group). At the same time, the rest of injected oocytes from ICSI cycles include in this study were used as control group. Fertilization and embryo development parameters were used to explore the efficiency and application value of rescue artificial activation for after fertilization failure oocytes ICSI.Results:Time-lapse monitoring showed that the fertilization rate and 2PN fertilization rate were 99.91% and 97.76% in the Pb2-exclusion group, 0.03% and 0% in the without Pb2-exclusion group after ICSI, with significant differences between the two groups ( P<0.001); the exclusion time of Pb2 after ICSI was (3.04±1.45) h, and the distribution and proportion of Pb2 exclusion time were 0-3 h (58.00%), 3-5 h (36.29%), 5-8 h (3.92%) and >8 h (1.21%). The Pb2 exclusion rate, the fertilization rate and the 2PN fertilization rate in NAOA group were all 0%, and the 2PN fertilization rate (36.00%), day 3 (D3) high-quality embryo rate (8.00%), day 5 (D5) blastocyst formation rate (0%) and D5 high-quality blastocyst formation rate (0%) in LAOA group were significantly lower than those in RAOA group (60.00%, 44.19%, 51.16%, 25.58%) ( P=0.005, P=0.002, P<0.001, P=0.005), and also in control group (97.63%, 48.62%, 63.23%, 37.94%) ( P<0.001); the Pb2 exclusion rate (84.00%), the fertilization rate (81.33%), the 2PN fertilization rate (60.00%) and the 2PN cleavage rate (95.56%) in RAOA group were significantly lower than those in control group (100.00%, 99.68%, 97.63%, 99.51%) ( P<0.001, P<0.001, P<0.001, P=0.04). However, there was no significant difference in D3 high-quality embryo rate, D5 blastocyst formation rate and D5 high-quality blastocyst formation rate between the two groups ( P>0.05). Conclusion:Time-lapse monitoring of the Pb2 exclusion can be used as an early judgment indicator of fertilization failure in ICSI cycles. Rescue artificial activation of fertilization failed oocytes in 5 h after ICSI can achieve normal fertilization and acceptable embryo development outcomes.

Objective:To establish a technical system for early judgment and rescue artificial oocyte activation of oocytes after fertilization failed, intracytoplasmic sperm injection (ICSI) and to explore the activation efficiency and application value.Methods:Firstly, a retrospective analysis was performed in 150 ICSI cycles cultured by Time-lapse system during January 2017 to March 2018 from Reproductive Medical and Genetic Center, the People's Hospital of Guangxi Zhuang Autonomous Region, the time distribution of the second polar body (Pb2) exclusion and its relationship with fertilization and embryo development outcomes, the feasibility of Pb2 exclusion as an early indicator of fertilization failure in ICSI was discussed. Secondly, 225 fertilization failed oocytes from 93 ICSI cycles during March 2018 to June 2019 were collected for randomized controlled trials according to different artificial activation modes. They were divided into three groups including non-activation group (NAOA group), rescue activation group (RAOA group) and late activation group (LAOA group). At the same time, the rest of injected oocytes from ICSI cycles include in this study were used as control group. Fertilization and embryo development parameters were used to explore the efficiency and application value of rescue artificial activation for after fertilization failure oocytes ICSI.Results:Time-lapse monitoring showed that the fertilization rate and 2PN fertilization rate were 99.91% and 97.76% in the Pb2-exclusion group, 0.03% and 0% in the without Pb2-exclusion group after ICSI, with significant differences between the two groups ( P<0.001); the exclusion time of Pb2 after ICSI was (3.04±1.45) h, and the distribution and proportion of Pb2 exclusion time were 0-3 h (58.00%), 3-5 h (36.29%), 5-8 h (3.92%) and >8 h (1.21%). The Pb2 exclusion rate, the fertilization rate and the 2PN fertilization rate in NAOA group were all 0%, and the 2PN fertilization rate (36.00%), day 3 (D3) high-quality embryo rate (8.00%), day 5 (D5) blastocyst formation rate (0%) and D5 high-quality blastocyst formation rate (0%) in LAOA group were significantly lower than those in RAOA group (60.00%, 44.19%, 51.16%, 25.58%) ( P=0.005, P=0.002, P<0.001, P=0.005), and also in control group (97.63%, 48.62%, 63.23%, 37.94%) ( P<0.001); the Pb2 exclusion rate (84.00%), the fertilization rate (81.33%), the 2PN fertilization rate (60.00%) and the 2PN cleavage rate (95.56%) in RAOA group were significantly lower than those in control group (100.00%, 99.68%, 97.63%, 99.51%) ( P<0.001, P<0.001, P<0.001, P=0.04). However, there was no significant difference in D3 high-quality embryo rate, D5 blastocyst formation rate and D5 high-quality blastocyst formation rate between the two groups ( P>0.05). Conclusion:Time-lapse monitoring of the Pb2 exclusion can be used as an early judgment indicator of fertilization failure in ICSI cycles. Rescue artificial activation of fertilization failed oocytes in 5 h after ICSI can achieve normal fertilization and acceptable embryo development outcomes.

Objective: To evaluate the composite external fixation in the treatment of children with fracture of lower extremity metaphysis. Methods: A retrospective analysis was conducted of the 42 children with fracture of lower extremity metaphysis who had been admitted to Zhengda Shaoyang Orthopaedic Hospital between September 2016 and September 2018. They were 24 boys and 18 girls, aged from 3 to 14 years (mean, 8.3 years). Open injury occurred in 10 cases, with type Ⅰ in 2, type Ⅱ in 7 and type Ⅲ in one according to the Gustilo-Anderson classification, and closed injury in the other 32 ones. The fracture happened at distal femur in 12, at proximal tibia in 9 and at distal tibia in 21 cases. All the patients were fixated with composite external brackets. Fracture healing, functional recovery of the knee and ankle joints, and complications were recorded. Results: All the 42 patients were followed up for 12 to 18 months (mean, 15.8 months). All fractures healed well by the first intention with no malunion or no alignment change on the full length X-ray films of both lower limbs. Irritant growth within 1.5 cm was observed in 2 cases. No loosening occurred in the external fixation which was removed 3 to 5 months after surgery (mean, 3.8 months). Functional recovery of the knee and ankle joints was good at the last follow-up. For the patients with distal femoral metaphysis fracture, the knee function by the Merchan scoring was excellent in 3 cases, good in 7 cases, fair in one and poor in one; for the patients with proximal tibial metaphysis fracture, the knee function by the Merchan scoring was excellent in 3, good in 4 and fair in 2 cases; for the patients with distal tibial metaphysis fracture, the ankle function by the Kofoed scoring was excellent in 11, good in 7 and fair in 3 cases, giving an excellent and good rate of 83.3%. Of a total of 228 needle channels in the 42 patients, 58 were infected mildly or moderately, giving an infection rate of 25.4%. All the infections responded to active dressing change. Conclusion The composite external fixation brackets are a good choice for the treatment of children with fracture of lower extremity metaphysis, because they are easy in manipulation and stable in configuration, and can reduce the iatrogenic injury to the epiphyseal plate, spare cross-articular fixation and allow early functional exercise.