Vascular anastomosis is one of the most basic techniques of microsurgery, and the quality of anastomosis largely determines the success of the surgery. With the continuous development of microsurgical techniques, more and more new technologies have been used in vascular anastomosis, but hand suturing is still the "gold standard" method for microvascular anastomosis. This article summarized the advantages and disadvantages as well as application of traditional microvascular suturing techniques and improved techniques and their methods at home and abroad, aiming to provide reference for clinical application of microvascular suturing techniques.

Objective:To study the influence of different feeding patterns on mother-to-child transmission (MTCT) of hepatitis B virus (HBV) in pregnant women with high viral loads who received antiviral medication during pregnancy to the day of delivery.Methods:This prospective cohort study was conducted in Beijing You'an Hospital. From January 1, 2019, to March 31, 2020, and 574 pregnant women with positive hepatitis B surface antigen (HBsAg) and HBV DNA>2×10 5 IU/ml were enrolled. All participants received tenofovir, telbivudine, lamivudine, or propofol tenofovir from 24-28 weeks of gestation and discontinued on the day of delivery, and their neonates were postnatally given routine passive-active immunoprophylaxis. Based on the feeding patterns, the subjects were divided into three groups: breastfeeding ( n=257), bottle-feeding ( n=241) and mixed feeding groups ( n=76). The follow-up data were obtained from liver functions and HBV DNA level of the mothers at 6-8 weeks postpartum and HBV serological markers of infants at 7-12 months. One-way ANOVA, Student-Newman-Keuls, Chi-square test or Fisher exact test, and repeated measures ANOVA were used to analyze the data. Results:The average maternal HBV DNA levels before antiviral treatment did not differ significantly between the three groups [(7.90±0.67), (7.82±0.70), (7.83±0.70) log 10 IU/ml, F=0.912, P>0.05]. HBV DNA level before delivery in the mixed feeding group was slightly lower than that in the breastfeeding and bottle-feeding group [(3.87 ±1.08) vs (4.21±1.17) and (4.30±1.28) log 10 IU/ml, q= 3.052 and 3.831, both P<0.05], while the comparison between the latter two groups showed no significant differences ( P>0.05). After delivery, HBV DNA level in the bottle-feeding group was slightly lower than that in the breastfeeding group [(7.42±0.93) vs (7.69±0.90) log 10 IU/ml, q=4.583, P<0.05]. Among 580 infants (including six pairs of twins), only one bottle-fed infant (0.4%, 1/243) was infected with HBV through MTCT, and none in the breastfeeding or mixed feeding group ( P=0.553). Conclusions:For pregnant women with high viral loads of HBV who have received antiviral medication during pregnancy, although HBV DNA level will rebound after discontinuation upon delivery, breastfeeding is recommended considering it does not increase the risk of MTCT.

Objective To establish a neural network model based on enhanced CT for distinguishing ISUP grade of clear cell renal cell carcinoma (ccRCC). Methods We collected 131 cases of ccRCC, with 92 cases of low ISUP grade and 39 cases of high ISUP grade. Patients were divided into training set and validation set according to 5:5 stratified sampling. The enhanced CT images of each ccRCC patient were evaluated by the radiologist. Recursive feature elimination (RFE) was used to reduce the dimension of patients' general features and enhanced CT features, which was used for neural network modeling and validation. Results Patients' general features and enhanced CT features were verified by RFE method and then reduced to 14 features. The top 5 features were growth pattern, necrosis, enlargement of lymph nodes, tumor size and capsule. The AUC of the neural network model based on these 5 features in training set was 0.8844 (95%CI: 0.8062-0.9626), sensitivity was 89.47% and specificity was 82.61%; and those in validation set were 0.7924 (95%CI: 0.6567-0.9280), 75.00% and 86.96%, respectively. Conclusion The neural network model of ccRCC ISUP grade based on enhanced CT has relatively high diagnostic efficiency.

Objective: To explore the relationship between driver gene mutation (JAK2, MPL and CALR) and disease type in BCR-ABL negative myeloproliferative neoplasms (MPNs) including primary myeloid fibrosis (PMF), essential thrombocytosis (ET) and polycythemia vera (PV). Methods: A total of 32 MPN related genes were detected by high-throughput sequencing in 156 MPN patients. The relationships between disease type and patients′ general performance, the characteristics of driver gene mutations, concomitant gene mutations were analyzed. Results: In the population with JAK2 V617F positive mutation, the proportion of patients over 60 years old in PMF was higher than that with ET or PV. By high-throughput sequencing, 22 concomitant gene mutations were detected in 46 patients with JAK2, MPL or CALR mutations, including 4 (8.3%) in PV, 20 (29.4%) in ET, and 22 (55.0%) in PMF. DNMT3A mutation was detected only in patients with PV, while splicing factor related genes including SF3B1, SRSF2 and U2AF1 were only accompanied by PMF. According to the variation allele frequency (VAF) value of JAK2 V617F mutation, the VAF value associated with PV was the highest (68.15%), followed by PMF (37.7%) and ET (23%). However, there were significant differences in the incidence of JAK2 V617F homozygous among 3 different diseases. In patients with JAK2 mutation, the proportion of other gene mutations in PV and ET was significantly lower than that in PMF. Conclusions Under the condition of common driver gene mutations (JAK2, MPL and CALR), patients′ age, VAF value and homozygous state, concomitant gene mutations are closely related to different disease type. These correlations help to improve clinical understanding of disease characteristics and risk assessment.

Objective:To explore the characteristics and clinical significance of clonal heterogeneity in patients with acute lymphoblastic leukemia(ALL).Methods:From January 2016 to June 2019, 170 newly diagnosed ALL patients were enrolled in the Department of Hematology, Henan Cancer Hospital, including 93 males and 77 females, with a median age of 17 (2-80) years. Fifty-two ALL-related genes were detected by high-throughput sequencing technique. The clonal heterogeneity of mutations was analyzed according to the variant allele frequency (VAF) and the results of flow cytometry. The prognostic value of mutations was also evaluated.Results:Gene mutations were detected in 121 (71.2%, 121/170) patients, of which 2 or more clones were detected in 18 (52.9%, 18/34) T-cell acute lymphoblastic leukemia patients, while only 23 (16.9%, 23/136) B-cell acute lymphoblastic leukemia patients were positive of multiple mutations ( P<0.01).Gene mutation-related clonal heterogeneity analysis showed that 2 or more clones were frequent in patients with NOTCH1 mutations (13/19 patients) ( P<0.01). Event free survival (EFS) in patients with 3 or more clones was significantly lower than other patients (χ 2=10.330, P=0.016). Child ALL patients had similar result, that multiple clones predicted lower overall survival (OS) and EFS (OS: χ 2=7.974, P=0.047; EFS: χ 2=10.860, P=0.013). Conclusion:Clonal heterogeneity in ALL patients is closely related to the different origin of lymphocyte lineages and the age of onset, which may reveal the nature of the disease and predict the clinical outcome.

Objective:This study aimed to explore the characteristics and clinical value of clonal heterogeneity in acute myeloid leukemia (AML) .Method:A high-throughput sequencing was carried out to detect 68 related genes in 465 AML patients. Clonal heterogeneity was analyzed based on variant allele frequency (VAF) and flow cytometry results combined with clinical data.Results:Gene mutations were discovered in 338 (81.4%) newly diagnosed patients, and 2 or more clones were significantly increased in patients with DNMT3A, NRAS, and RUNX1 mutations (DNMT3A, χ2=15.23; P<0.001; NRAS, χ2=19.866; P<0.001; RUNX1, χ2=23.647; P<0.001) . The number of clones significantly differed between groups at different ages ( χ2=17.505, P=0.022) . The proportion of carrying 2 and ≥3 clones increased in patients aged more than 60 years old. There was a significant difference in the clonal heterogeneity between newly diagnosed patients and relapsed or secondary patients ( χ2=11.302, P=0.010) . Moreover, the proportion of patients with clonal heterogeneity gradually increased according to their prognostic risk ( χ2=17.505, P=0.022) . Based on the clone analysis, the proportion of primary clones of patients with RUNX1 mutation was higher ( χ2=4.527, P=0.033) . The analysis of clonal heterogeneity and efficacy demonstrated that patients with three or more clones had significantly lower overall survival (OS) and progression-free survival (PFS) compared to other patients (OS, χ2=13.533; P=0.004; PFS, χ2=9.817; P=0.020) , while in the intermediate-risk group, patients with a significant clonal heterogeneity also exhibited a significant decrease in PFS ( χ2=10.883, P=0.012) . Cox regression multivariate analysis revealed that carrying three or more clones was an independent factor affecting prognosis, and OS and PFS were significantly lower than those of patients without clones (OS, HR=3.296; 95% CI, 1.568-6.932; P=0.002; PFS, HR=3.241; 95% CI, 1.411-7.440; P=0.006) . Conclusion:Clonal heterogeneity may reflect the biological characteristics of a tumor, suggesting its drug resistance, refractory, and invasiveness, and further evaluate the treatment effect and prognosis of patients.

Objective:To explore the influence of the second stage of labor>2 hours of new birth process standards on preventing mother-to-child transmission and delivery outcome among chronic hepatitis B puerperas.Methods:Clinical data of 100 puerperas with hepatitis B virus (HBV) were retrospectively analyzed in Beijing YouAn Hospital from January 1 2014 to December 1 2018. Puerpera with the second stage of labor >2 hours were in observation group, and puerperas with the second stage of labor<2 hours were in control group, 50 cases in each group. The follow-up of two groups was carried out until neonate aged 7 months. This study compared the main outcome measures (the rate of mother-to-child transmission of HBV) and the secondary outcome measures (surgical delivery, rate of lateral perineal incision, blood loss during delivery and 2 hours after delivery, incidence of neonatal asphyxia) between two groups.Results:There was no statistical difference in the number of neonate with positive HBsAg during delivery between two groups ( P>0.05) ; there was no neonate aged 7 months with positive HBsAg between two groups. Numbers of lateral perineal incision, surgical delivery and blood loss during delivery in observation group increased compared with those in control group with statistical differences ( P<0.05) . There were no statistical differences in the incidence of neonatal asphyxia and blood loss 2 hours after delivery between two groups ( P>0.05) . Conclusions:The second stage of labor >2 hours of new birth process standards is carried out without increasing the rate of mother-to-child transmission of hepatitis B, but it increases rates of surgical delivery, lateral perineal incision and blood loss during delivery. We should comprehensively consider and discuss when implementing the new birth process management in hepatitis B puerperas so as to assure the safety of months and infants.

Objective: To establish a new method for chimerism analysis after allogeneic hematopoietic stem cell transplantation by using multiple nucleotide polymorphism sequencing (MNPseq) , and to explore its feasibility and superiority. Methods: One hundred MNP fragments were screened and chimeric analysis was performed by high-throughput sequencing technology. The accuracy and sensitivity of the method were verified by simulating chimeric samples and post-transplant samples and comparing them with short tandem repeat (STR) analysis, fusion gene quantitative detection and flow cytometry for minimal residual disease. Results: The accuracy and sensitivity of MNPseq were better than those of STR, in which the sensitivity could reach 0.01%, about 100 times more sensitive than STR. MNPseq could further distinguish 42 STR fully chimeric samples, and after corrected by cutoff value, it was correlated with the quantitative detection of fusion gene. MNPseq could correct false positive of STR caused by the shadow peak, and could be used to detect chimeric samples lacking pre-transplant information from donors and recipients. Conclusion MNPseq analysis based on high-throughput sequencing is a more accurate and sensitive chimerism detection method, and it solves the problem that chimerism cannot be detected due to the lack of pre-transplant information, which has extremely high clinical application value.

Objective: To report the operation methods and clinical effects of repairing finger tip defect with the free tibial dorsal nerve flap of the second toe. Methods: 13 patients with finger tip defects were repaired by the tibial dorsal nerve flap of the second toe. The area of finger tip defect was 2.5 cm×1.5 cm-1.3 cm×1.0 cm, and the area of cutting flap was 2.7 cm×1.7 cm-1.5 cm×1.1 cm. All donor site defects on the second toe were covered with full-thickness skin graft. Results: There were 13 cases in this group, and all the flaps and skin grafts were survived. Postoperative follow-up ranged from 6 to 18 months, with an average of 13 months. The appearance of the fingers was satisfied and the sensory recovery was good. Two-point discrimination of the flaps returned to 7-13 mm, with an average of 9 mm. According to the total active move(TAM)scale, results were excellent in 11 fingers, good in 1 finger, and fair in 1 finger. The donor site skin graft was well healed, the second toe pulp was full, and the two-point discrimination of the toe pulps were 6-10 mm, with an average of 8 mm. Conclusions Compared to the traditional method of repairing finger tip defect with the tibial inherent nerve flap of the second toe, our new method can reduce the damage to the donor site, and we can repair finger tip defect as well as the traditional one at the same time. So it was a better operative method to repair finger tip defect with the tibial dorsal nerve flap of the second toe.

Objective: To explore the application and effect of using the lateral second toe flap transfer for reconstruction of great toe defect. Methods: The flap on tibial of second toe was designed according to the size of defect. The pedicle of the flap is the tibial proper plantar digital artery of the toe, and the rotation point is located between the toe web.13 cases of the great toe′s defects were repaired by this method, with the donor sites covered by full thickness skin from the leg. Results: 13 flaps survived postoperatively. All cases were subject to postoperative follow-up, follow-up time was 6-48 months, an average of 18 months. Skin color and texture was close to that of the surrounding tissues, appearance is not bloated. Conclusions The second toe lateral skin flap is easy to operate, is flexible for rotating. As local material, it is an ideal skin flap to repair the great toe defect.