BACKGROUND:Central pancreatectomy is a surgical treatment for tumors at the neck or the middle part of the pancreas, which can reserve more normal pancreas, not cut adjacent organs, and reduce the incidence of postoperative internal and external pancreatic secretion deficiency with respect to the expanded proximal and distal pancreatectomy. OBJECTIVE: To systematicaly evaluate the clinical efficacy of the central pancreatectomy and distal pancreatectomy. METHODS: A computer-based search of Chinese and English databases was performed, and then 15 controled clinical trials were included and systematicaly evaluated using RevMa5.2 software. RESULTS AND CONCLUSION: Totaly 1 079 cases were included in this study, which consisted of 436 central pancreatectomy cases and 643 distal pancreatectomy cases. Meta-analysis showed that compared with the distal pancreatectomy group, the incidences of postoperative pancreatic fistula and complications were significantly higher, the risk of postoperative endocrine and exocrine insufficiency were significantly lower, while the surgical time (SMD: 59.23, 95%CI: 22.41-96.05, P < 0.01) and hospital stays (SMD: 7.01, 95%CI: 1.94-12.09,P< 0.01) were longer in the central pancreatectomy group. These findings indicate that although the central pancreatectomy has a high postoperative complication incidence, it can be accepted clinicaly, which may be a reasonable operation method to preserve pancreatic exocrine and endocrine function.

Objective To investigate the approaches and effect of Ilizarov external fixators combined with limited operation in treatment of posttraumatic clubfoot in children.Methods The study involved 40 cases (43 feet) of posttraumatic clubfoot treated with Ilizarov external fixators combined with limited operation including soft-tissue releases (26 cases,28 feet) or osteotomies (14 cases,15 feet)from January 2006 to June 2012.Scoring system of intemational clubfoot study group (ICFSG) including aspects of functional assessment (36 points),morphology (12 points) and radiological assessment (12points) were employed before and after surgery.Results All the cases were available to the follow-up of 0.5-6 years.ICFSG score was excellent in 28 feet,good in 10,fair in four and poor in one foot,with excellent-good rate of 88％.This suggested the good correction of posttraumatic clubfoot,satisfactory weight-bearing exercise and a low relapse rate.Conclusions Conservative open operation brings large trauma and poor results in treatment of posttraumatic clubfeet in children,while Ilizarov invasive distraction technique is probable to offset those weak points.Therefore,Ilizarov external fixators combined with limited operation is an effective treatment.

To study alkaloid constituents in Corydalis decumbens,thirteen compounds were isolated from 95％ ethanol extracts of Corydalis decumbens (Thunb) Pers.by silica gel,RP-C1s,Sephadex LH-20 column chromatographer,recry stallization,thin-layer chromatography and HPLC.Their structures were elucidated on the basis of spectral data combined with physiochemical properties as tetrahydropalmatine (1),oxyhydrastinine (2),doryanine (3),palmatine (4),bicuculline (5),canadine (6),tetrahydrocoptisine(7),corydaldine (8),epicorynoxidine (9),N-methylcorydaldine (10),(+)-corlumine (11),N-methyl-6,7-dimethoxyisoquinolone (12) and oxysanguinarine (13).Compounds 2,3,6,7,and 9-13 were isolated from this plant for the first time.In addition,compounds 2,3,and 9-13 were obtained firstly from this genus.Pharmacological experiments showed that tetrahydropalmatine (1) might have analgesic or sedative effects,and the bicuculline (5) could probably induce epilepsy.

Chemical investigation of the roots of Uvaria grandiflora by repeated column chromatography(CC)over silica gel, ODS, Sephadex LH-20, and HPLC resulted in the isolation of twelve compounds. Their structures were identified as: epicatechin-(4β→1′, 2→O→2′)-phloroglucinol(1), proanthocyanidin A-1(2), proanthocyanidin A-2(3), epicatechin(4), phlorizin(5), eriodictyol(6), erythro-guaiacylglycerol-8-O-4′-(coniferyl alcohol)ether(7), threo-guaiacylglycerol-8-O-4′-(coniferyl alcohol)ether(8), erythro-guaiacylglycerol-8-O-4′-(sinapyl alcohol)ether(9), threo-syringylglycerol-8-O-4′-(sinapyl alcohol)ether(10), burselignan(11)and icariol A2(12). Compounds 1 to 12 were all isolated from this plant for the first time, and compound 1 was a new natural product.

Objective:To investigate the effectiveness of new cryoprotective agents in preserving and transplanting human adipose tissue.Methods:The adipose tissue samples were obtained from healthy adult females who underwent liposuction at the Department of Plastic Surgery of Peking University Third Hospital from January to March 2022. The adipose tissue samples were centrifuged and then randomly divided into 9 groups. These groups were cryopreserved in liquid nitrogen using different cryoprotective agents [group A, group B, and dimethyl sulfoxide (DMSO) group] and cryopreservation times (1-month, 2-month, and 3-month groups), respectively. The cryoprotective agent formulation in group A was dextrose glycoside 40 (DEX), amino acids, vitamins, and inorganic salts. In group B, the formulation included DMSO and DEX. The ratio of cryoprotective agent in the DMSO group was 10% DMSO, 20% fetal bovine serum (FBS), and 70% DMEM-12. For cryopreservation, 5 ml cryogenic tubes were used with a fat to cryoprotective agent ratio of 3∶2, and each group contains 6 tubes for cryopreservation. After thawing the adipose tissue, HE staining was used to observe the histological morphology. Immunohistochemical staining was employed for the quantitative analysis of lipid droplet-encapsulated protein (Perilipin), and the Perilipin positivity rate was calculated by the ratio of the number of positive cells to the total number of cells. Adipocyte viability was assessed using the CCK-8 method. Thirty-eight healthy, clean nude mice were selected and divided into 3 groups of 12 mice each according to the use of different cryoprotective agents (groups A, B, and DMSO), while the other 2 mice were used as the day 0 control group. The mean fat freezing duration for all groups was 3 months. After nude mice were anesthetized intraperitoneally, 0.9 ml of thawed cryopreserved fat was injected into the dorsum bilaterally. The rate of adipose tissue retention was calculated by MRI scanning and three-dimensional software at 1, 2, and 3 months after transplantation, and compared between the groups. The fat grafts were explanted from the mice after they were sacrificed, and then subjected to histological morphology and quantitative analysis of Perilipin by using HE staining and immunohistochemical staining. GraphPad Prism 8.0 software was used for statistical analysis of the data. The data that conformed to a normal distribution were expressed as Mean ± SD. The overall comparison between multiple groups used analysis of variance for repeated measures. The comparison of data between groups at the same time point used Tukey’s multiple comparison test.Results:The morphology of adipose tissue in different cryoprotective agent groups closely resembled that of normal fresh adipose tissue after being cryopreserved in liquid nitrogen for 1-3 months. The difference in the proportion of Perilipin-stained positive cells in each group was not statistically significant ( P>0.05). The CCK-8 method indicated that the effect of the DMSO group was superior to groups A and B at 1 and 3 months of cryopreservation ( P<0.01), and that the DMSO group and group B were superior to group A at 2 months of cryopreservation ( P<0.01). In the animal experiments, there was no statistically significant difference between the groups in the volume retention rate 1-3 months after cryopreserved fat transplantation ( P>0.05). Additionally, the adipose tissues in each group exhibited varying degrees of localized necrosis accompanied by an inflammatory reaction 1-3 months after transplantation. There was no statistically significant difference in the Perilipin staining positivity between the groups ( P>0.05). Conclusion:The use of new cryoprotective agents for cryopreserving adipose tissue does not show a significant difference compared to the traditional cryoprotective agent. However, it is theoretically safer as it avoids the potential toxic effects of using DMSO or FBS on the human body.

Objective:To investigate the effectiveness of new cryoprotective agents in preserving and transplanting human adipose tissue.Methods:The adipose tissue samples were obtained from healthy adult females who underwent liposuction at the Department of Plastic Surgery of Peking University Third Hospital from January to March 2022. The adipose tissue samples were centrifuged and then randomly divided into 9 groups. These groups were cryopreserved in liquid nitrogen using different cryoprotective agents [group A, group B, and dimethyl sulfoxide (DMSO) group] and cryopreservation times (1-month, 2-month, and 3-month groups), respectively. The cryoprotective agent formulation in group A was dextrose glycoside 40 (DEX), amino acids, vitamins, and inorganic salts. In group B, the formulation included DMSO and DEX. The ratio of cryoprotective agent in the DMSO group was 10% DMSO, 20% fetal bovine serum (FBS), and 70% DMEM-12. For cryopreservation, 5 ml cryogenic tubes were used with a fat to cryoprotective agent ratio of 3∶2, and each group contains 6 tubes for cryopreservation. After thawing the adipose tissue, HE staining was used to observe the histological morphology. Immunohistochemical staining was employed for the quantitative analysis of lipid droplet-encapsulated protein (Perilipin), and the Perilipin positivity rate was calculated by the ratio of the number of positive cells to the total number of cells. Adipocyte viability was assessed using the CCK-8 method. Thirty-eight healthy, clean nude mice were selected and divided into 3 groups of 12 mice each according to the use of different cryoprotective agents (groups A, B, and DMSO), while the other 2 mice were used as the day 0 control group. The mean fat freezing duration for all groups was 3 months. After nude mice were anesthetized intraperitoneally, 0.9 ml of thawed cryopreserved fat was injected into the dorsum bilaterally. The rate of adipose tissue retention was calculated by MRI scanning and three-dimensional software at 1, 2, and 3 months after transplantation, and compared between the groups. The fat grafts were explanted from the mice after they were sacrificed, and then subjected to histological morphology and quantitative analysis of Perilipin by using HE staining and immunohistochemical staining. GraphPad Prism 8.0 software was used for statistical analysis of the data. The data that conformed to a normal distribution were expressed as Mean ± SD. The overall comparison between multiple groups used analysis of variance for repeated measures. The comparison of data between groups at the same time point used Tukey’s multiple comparison test.Results:The morphology of adipose tissue in different cryoprotective agent groups closely resembled that of normal fresh adipose tissue after being cryopreserved in liquid nitrogen for 1-3 months. The difference in the proportion of Perilipin-stained positive cells in each group was not statistically significant ( P>0.05). The CCK-8 method indicated that the effect of the DMSO group was superior to groups A and B at 1 and 3 months of cryopreservation ( P<0.01), and that the DMSO group and group B were superior to group A at 2 months of cryopreservation ( P<0.01). In the animal experiments, there was no statistically significant difference between the groups in the volume retention rate 1-3 months after cryopreserved fat transplantation ( P>0.05). Additionally, the adipose tissues in each group exhibited varying degrees of localized necrosis accompanied by an inflammatory reaction 1-3 months after transplantation. There was no statistically significant difference in the Perilipin staining positivity between the groups ( P>0.05). Conclusion:The use of new cryoprotective agents for cryopreserving adipose tissue does not show a significant difference compared to the traditional cryoprotective agent. However, it is theoretically safer as it avoids the potential toxic effects of using DMSO or FBS on the human body.

The interventional therapy of vascular stent implantation is a popular treatment method for cardiovascular stenosis and blockage. However, traditional stent manufacturing methods such as laser cutting are complex and cannot easily manufacture complex structures such as bifurcated stents, while three-dimensional (3D) printing technology provides a new method for manufacturing stents with complex structure and personalized designs. In this paper, a cardiovascular stent was designed, and printed using selective laser melting technology and 316L stainless steel powder of 0-10 µm size. Electrolytic polishing was performed to improve the surface quality of the printed vascular stent, and the expansion behavior of the polished stent was assessed by balloon inflation. The results showed that the newly designed cardiovascular stent could be manufactured by 3D printing technology. Electrolytic polishing removed the attached powder and reduced the surface roughness Ra from 1.36 µm to 0.82 µm. The axial shortening rate of the polished bracket was 4.23% when the outside diameter was expanded from 2.42 mm to 3.63 mm under the pressure of the balloon, and the radial rebound rate was 2.48% after unloading. The radial force of polished stent was 8.32 N. The 3D printed vascular stent can remove the surface powder through electrolytic polishing to improve the surface quality, and show good dilatation performance and radial support performance, which provides a reference for the practical application of 3D printed vascular stent.
Humans ; Stainless Steel ; Powders ; Cardiovascular System ; Constriction, Pathologic