Objective To observe the host response and the expression of interleukin-4 (IL-4) in different cross-linked hyaluronic acid composite gels at different time points after the implantation in vivo, and to explore the significance of biocompatibility and macrophage polarization in post-implantation inflammatory response and tissue remodeling. Methods New Zealand white rabbits were respectively injected with crosslinked hyaluronic acid-crosslinked hydroxypropyl methylcellulose gel (sample 1), crosslinked hyaluronic acid-hydroxypropyl methylcellulose gel (sample 2) and commercially available modified sodium hyaluronate gel (control) in subcutaneous tissue at both sides of the spine. Then the rabbits were dissected at 1, 4 and 12 weeks after the implantation. The tissues were fixed with 10％formaldehyde solution, embedded in paraffin and sliced. Hematoxylin-eosin (HE) staining was performed to observe the degree of inflammation and fibrosis. Masson staining was performed to observe the formation of collagen fibers. Immunohistochemical staining was performed to observe the expression of IL-4. Results The results of HE staining showed that the inflammatory reaction in the sample 1 and sample 2 groups was significantly higher than that in the control group 1 and 4 weeks after the implantation. The inflammatory cells aggregated, and the wall of capsule and microcapsule was thick. The sample 1 group was more obvious, and the result was mild stimulation. For all the groups, the results were all non-irritating at 12 weeks after the implantation. The results of Masson staining showed that the collagen fibers in the sample 1 and sample 2 groups were increased compared with the control group, mainly distributed around the implantation site, and a small amount among the gels after 1 and 4 weeks. After 12 weeks, the collagen fibers were further increased, especially among the gels, which were consistent with the control group. The results of immunohistochemical staining showed that, at the same time point, the expression of IL-4 in sample 1 and sample 2 groups was higher than that in the control group, and the expression of IL-4 increased gradually with time. The expression of IL-4 in the control and sample 1 group at 12 weeks after the implantation was higher than that at 1 and 4 weeks respectively, and the differences were statistically significant (all P<0.05). In the sample 1 group, the expression of IL-4 at 12 weeks after the implantation was higher than that at 1 week, and the difference was statistically significant (P<0.05). The expression of IL-4 in the sample 1 group was significantly higher than that in the control group at 4 weeks after the implantation, and the difference was statistically significant (P<0.05). Conclusions The two different cross-linked sodium hyaluronate composite gels have good biocompatibility. The formation of collagen fiber and the expression of IL-4 can gradually increased within 12 weeks after the subcutaneous implantation, which is beneficial to the tissue remodeling.

In order to figure out the status and distribution of the wild and cultivated resources of traditional Chinese medicine Daphnes Cortex, its suitable habitat and endangering factors were analyzed to provide the basis for its rational use, protection and cultivation.Our research group tooka resources survey in Shanxi, Gansu, Sichuan and Qinghai provinces, which include 23 counties. Investigation and sampling investigation combined with interview were carried out. The total reserve of resources was estimated through route-quadrat method in combination with the vegetation and soil-type map area method. The results indicated that there was no obvious change between the present distribution ranges of the wild Daphnes Cortex and its historical records, but the density of the population has undergone major changes. The wild reserves resources has declined seriously, even on the verge of exhaustion in some regions. According to the survey results, the current total reserve of the wild Daphnes Cortex in the four provinces was no more than 600 tons. Simultaneously, we only found the cultivated resource in a mountain at an altitude of about 2 800 m in Kang county of Gansu province, which cropping scope was about 33 000 m². The cultivated resource can't provide medicinal products at present, because their growing period is too short to have curative effect. Destructive excavation and the longer growth cycle result in a sharp decline of the wild resources reserves, even to the point of extinction. Artificial cultivation of product will become the main source of medicinal resources in the future. Therefore, we must protect its suitable habitat, formulate rational harvesting policy, strengthen the supervision of government departments, collect and establish the germplasm nursery and seed bank. On the basis, we must carry out studies into seed-selecting and breeding as well as rapid propagation and growth technology at once.

Objective: To investigate the incidence of postoperative pancreatic fistula (POPF) and its risk factors after radical gastrectomy. Methods: The prospective study was conducted. The clinicopathological data of 2 089 patients who underwent radical gastrectomy in 22 medical centers between December 2017 and November 2018 were collected, including 380 in the Zhongshan Hospital of Fudan University, 351 in the Renji Hospital of Shanghai Jiaotong University School of Medicine, 130 in the Ruijin Hospital of Shanghai Jiaotong University School of Medicine, 139 in the Peking University Cancer Hospital, 128 in the Fujian Provincial Cancer Hospital, 114 in the First Hospital Affiliated to Army Medical University, 104 in the First Affiliated Hospital of Nanchang University, 104 in the Affiliated Hospital of Qinghai University, 103 in the Weifang People′s Hospital, 102 in the Fujian Medical University Union Hospital, 99 in the First Affiliated Hospital of Air Force Medical University, 97 in the Sir Run Run Shaw Hospital Affiliated to Zhejiang University School of Medicine, 60 in the Hangzhou First People′s Hospital Affiliated to Zhejiang University School of Medicine, 48 in the Fudan University Shanghai Cancer Center, 29 in the First Affiliated Hospital of Xi′an Jiaotong University, 26 in the Lishui Municipal Central Hospital, 26 in the Guangdong Provincial People′s Hospital, 23 in the Jiangsu Province Hospital, 13 in the First Affiliated Hospital of Sun Yat-Sen University, 7 in the Second Hospital of Jilin University, 4 in the First Affiliated Hospital of Xinjiang Medical University, 2 in the Beijing Chao-Yang Hospital of Capital Medical University. Observation indicators: (1) the incidence of POPF after radical gastrectomy; (2) treatment of grade B POPF after radical gastrectomy; (3) analysis of clinicopathological data; (4) analysis of surgical data; (5) risk factors for grade B POPF after radical gastrectomy. Measurement data with normal distribution were represented as Mean±SD, and comparison between groups was analyzed using ANOVA. Count data were described as absolute numbers or percentages, and comparison between groups was analyzed using the chi-square test. Univariate analysis was conducted using the t test or chi-square test based on data excluding missing data of clinico-pathological and surgical data. Multivariate analysis was conducted using the Logistic regression model based on factors with P<0.20 in univariate analysis. Results: There were 2 089 patients screened for eligibility, including 1 512 males, 576 females and 1 without sex information, aged (62±11)years. The body mass index (BMI) was (23±3)kg/m². (1) The incidence of POPF after radical gastrectomy: the total incidence rate of POPF in the 2 089 patients was 20.728%(433/2 089). The incidence rates of biochemical fistula, grade B pancreatic fistula, and grade C pancreatic fistula were 19.627%(410/2 089), 1.101%(23/2 089), 0, respectively. (2) Treatment of grade B POPF after radical gastrectomy: 2 of 23 patients with grade B POPF after radical gastrectomy had drainage tube placed for more than 21 days and received anti-infective therapy. Four of 23 patients with grade B POPF after radical gastrectomy had ascites detected by imaging examination, of which 2 received peritoneal drainage guided by ultrasound, 1 received failed puncture drainage, 1 received no puncture drainage, and they were given anti-infective therapy. Eleven of 23 patients with grade B POPF after radical gastrectomy had no ascites detected by imaging examinations, and they were given anti-infective therapy and inhibitors of pancreas secretion for clinical manifestation as fever or elevated white blood cells. Six patients with no typical clinical manifestations were given somatostatin to inhibite pancreas secretion and prolonged duration of abdominal drainage tube placement (with a median time of 7 days). All the 23 patients recovered well after treatment, without reoperation. (3) Analysis of clinicopathological data: for the 2 089 patients, BMI, cases with or without neoadjuvant therapy were (23±3)kg/m^2, 1 487, 160 of patients without pancreatic fistula, (23±3)kg/m^2, 386, 22 of patients with biochemical fistula, and (24±3)kg/m^2, 22, 1 of patents with grade B pancreatic fistula, showing significant differences between the three groups (F=5.787, χ²=8.269, P<0.05). (4) Analysis of surgical data: for the 2 089 patients, cases with open surgery, laparoscopic assisted surgery, totally laparoscopic surgery (surgical method), cases with D₁ lymph lode dissection, D₂ lymph lode dissection, and other lymph lode dissection (range of lymph lode dissection), cases with no omentectomy, partial omentectomy, and total omentectomy (range of omentectomy), cases with no usage of energy facility, usage of CUSA, LigaSure, LigaSure+ CUSA as energy facility, cases with or without biological glue, the number of lymph node dissection were 737, 624, 292, 24, 1 580, 51, 418, 834, 381, 63, 1 530, 23, 16, 1 431, 201, 33±14 of patients without pancreatic fistula, 146, 189, 74, 11, 389, 9, 110, 171, 128, 35, 359, 6, 9, 378, 31, 31±14 of patients with biochemical fistula, and 14, 5, 4, 0, 20, 3, 6, 13, 4, 2, 18, 1, 2, 22, 1, 37±16 of patients with grade B pancreatic fistula, showing significant differences between the three groups (χ²=15.578, 9.397, 15.023, 28.245, 8.359, F=4.945, P<0.05). (5) Risk factors for grade B POPF after radical gastrectomy: results of univariate analysis showed that usage of energy facility was a related factor for grade B POPF after radical gastrectomy (χ²=9.914, P<0.05). Results of multivariate analysis showed that laparoscopic assisted surgery, combined evisceration, application of LigaSure + CUSA, the number of lymph lode dissection were independent factors for for grade B POPF after radical gastrectomy (odds ratio=0.168, 3.922, 9.250, 1.030, 95% confidence interval: 0.036-0.789, 1.031-14.919, 1.036-82.602, 1.001-1.059, P<0.05). Conclusions The incidence of grade B POPF after radical gastrectomy is relatively low. Laparoscopic assisted surgery, combined evisceration, application of LigaSure + CUSA, and the number of lymph lode dissection are independent risk factors for grade B POPF. Trial Registration: This study was registrated at ClinicalTrial.gov in United States with the registration number of NCT03391687.