Elastin is a natural biomedical material of great potential. Being endowed with the special crosslinking and hydrophobic structure, elastin retains many good properties such as good elasticity, ductibility, biocompatibility, biodegradability and so on. Nowadays, elastin as a material, which is gradually attracting people' s attention in the biomedical materials field, has been used as tissue engineering scaffolds, derma substitutes and other biomedical materials. In this context, a systematic review on the characteristics of elastin as a biomedical material and on the actuality of its application is presented. Future developments of elastin in the field of biomedical applications are also discussed.
Biocompatible Materials ; Elastin ; chemistry ; physiology ; Humans ; Skin, Artificial ; Tissue Scaffolds

Objective: To investigate the risk factors of perineal incision complications after abdominoperineal resection (APR) for rectal cancer, and to establish a nomogram model to predict the complications of perineal incision. Methods: A case-control study was conducted to retrospectively collect the medical records of 213 patients with colorectal cancer who underwent APR at the First Affiliated Hospital of Nanjing Medical University from January 2010 to December 2016. The complications of perineal incision after APR were classified according to the modified Clavien-Dindo classification of surgical complications (Version 2019), and the complications of grade II and above were defined as "clinically significant complications" .Twenty-two factors related to complication of perineal incision, such as gender, age, surgical procedure, surgical approach, perineal repair, placement of drainage tube, skin position of drainage tube, operation time, intraoperative blood loss, preoperative radiotherapy and chemotherapy, intraoperative local perfusion chemotherapy, tumor classification, pathological grade, tumor T stage, tumor TNM stage and so on, were analyzed by chi-square test for univariate risk factor of complication in all variables, and variables with P<0.2 in univariate analysis were further included in multivariate analysis. Logistic regression analysis was used to screen out independent risk factors. R software (R 3.3.2) was introduced. The rms software package was used to construct a nomogram prediction model. The C-index was calculated (higher meaning better consistency with actual risk) to evaluate the discriminant degree of the model. The Bootstrap method was used to repeat the sampling for internal verification. A total of 42 patients with colorectal cancer who underwent APR from January 2017 to December 2017 at the First Affiliated Hospital of Nanjing Medical University were externally validated, and the corrected C-index was calculated. The model conformity was determined by comparing the C-index calibration difference between the predicted and actual risks. Results: Of the 213 patients with colorectal cancer, 131 were male and 82 were female, with mean age of (59.6±11.6) years. The incidence of postoperative perineal incision complications was 20.2% (43/213), including 27 cases of Clavien-Dindo II and above complications. Univariate analysis showed that the Eastern Cancer Cooperative Group (ECOG) score, preoperative albumin, skin position of drainage tube, intraoperative blood loss, preoperative radiotherapy and chemotherapy were associated with complications of postoperative perineal incision (All P<0.05) . Multivariate analysis showed that preoperative albumin levels ≤38 g/L (OR=105.261, 95% CI: 7.781 to 1423.998, P<0.001), perinead drainage (OR=11.493, 95% CI: 1.379 to 95.767, P=0.024), intraoperative blood loss >110 ml (OR=6.476, 95% CI: 1.505 to 27.863, P=0.012) and preoperative radiotherapy and chemotherapy (OR=7.479, 95% CI: 1.887 to 29.640, P=0.004) were postoperative clinically significant independent risk factors for perineal incision complications. The nomogram model was established. Preoperative albumin level <38 g/L was for 100 points, the preoperative chemoradiotherapy was for 52.5 points, the intraoperative blood loss >110 ml was for 28.5 points, and the perineal drainage was for 17.5 points. Adding all the points was the total score, and the complication rate corresponding to the total score was the predicted rate of the model. The model had a C-index of 0.863. After internal verification, the C-index dropped by 0.005. External verification showed a C-index of 0.841. Conclusions Preoperative nutritional status, skin position of drainage tube, intraoperative blood loss and preoperative radiotherapy and chemotherapy may affect the occurrence of perineal wound complications after APR for rectal cancer. The nomogram model constructed in this study is helpful for predicting the probability of clinically significant complications after APR.

Objective:To identify the potential intracranial inflammation in neuromyelitis optica spectrum disorders(NMOSD) patients without supratentorial MRI lesions using quantitative susceptibility mapping (QSM).Methods:Seventy NMOSD patients and 35 age- and gender-matched healthy controls (NC) underwent QSM, 3D-T 1, diffusion MRI from Beijing Tiantan Hospital during June 2019 to June 2021. Susceptibility was compared among NMOSD patients with acute attack (ANMOSD), NMOSD patients in chronic phase (CNMOSD) and NC. The correlation between susceptibility in several brain regions and the cerebrospinal fluid levels of inflammatory makers were analyzed. Results:NMOSD patients showed different susceptibility in several brain regions including bilateral hippocampus, precuneus, right cuneus, putamen, superior parietal and inferior temporal ( P<0.001) and the posr-hoc showed it is higher than normal. Compared to CNMOSD patients, the ANMOSD patients showed increased susceptibility in the cuneus (0.009 ± 0.004 vs. 0.005 ± 0.004, P<0.05). There was significant positive correlations between susceptibility and CSF levels of sTREM2 which reflect the active of microglial cells ( r = 0.494, P<0.05). Conclusions:Despite the absence of supratentorial lesions on MRI, increased susceptibility suggests underlying inflammation in the cerebral cortex in both patients with ANMOSD and CNMOSD, and some of them are obviously related to inflammatory markers in CSF. QSM sequence can be used to explore the potential inflammation in NMOSD patients without obvious supratentorial lesions.

OBJECTIVETo investigate the risk factors of postoperative perineal wound complications after abdominoperineal resection for rectal cancer.

METHODSThe databases of Medline, Embase, Web of Science, Ovid, Cochrane Library, CBM, CNKI, VIP and WANFANG were searched for the studies of abdominoperineal resection up to October 2016. The quality of the included studies was assessed by using "Cochrane collaboration's tool for assessing risk of bias" and "the Newcastle-Ottawa Scale". The meta-analyses were performed with Review Manager 4.3 software.

RESULTSEight randomized controlled trials and 33 non-randomized controlled trials with 15 287 patients were enrolled. Meta-analyses showed that neoadjuvant radiotherapy (OR=2.55, 95%CI: 1.66 to 3.93, P<0.01) and obesity (OR=2.12, 95%CI: 1.05 to 4.26, P=0.04) significantly increased the morbidity of perineal wound complication after abdominoperineal resection for rectal cancer; omentoplasty(OR=0.30, 95%CI: 0.14 to 0.67, P=0.003), presacral space clysis (OR=0.11, 95%CI: 0.01 to 0.94, P=0.04), abdominal drainage (OR=0.36, 95%CI: 0.21 to 0.63, P<0.01), perineal skin drainage(OR=41.72, 95%CI: 2.39 to 727.90, P=0.01) and local application of antibiotics (OR=0.17,95%CI: 0.07 to 0.40, P<0.01) significantly decreased the morbidity of perineal wound complication; however, extralevator abdominoperineal excision (OR=0.88, 95%CI: 0.57 to 1.35, P=0.56), laparoscopic procedure (OR=1.02, 95%CI: 0.47 to 2.21, P=0.96), biologic mesh reconstruction (OR=1.81, 95%CI: 0.95 to 3.46, P=0.07), myocutaneous flap reconstruction (OR=1.32, 95%CI: 0.18 to 9.91, P=0.79) and negative pressure drainage(OR=0.69, 95%CI: 0.35 to 1.34, P=0.27) had no influence on the healing of perineal wound.

CONCLUSIONSNumerous factors can affect the occurrence of perineal wound complication after abdominoperineal resection for rectal cancer. Due to the limitations of enrolled studies, multicenter large scale and high-quality randomized controlled trials are required to validate the current results.