Humans ; Stomach Neoplasms/pathology* ; Neoadjuvant Therapy ; Chemotherapy, Adjuvant ; Gastrectomy ; Antineoplastic Combined Chemotherapy Protocols/therapeutic use* ; Neoplasm Staging

Objective: To analyze the course of disease and epidemiological parameters of COVID-19 and provide evidence for making prevention and control strategies. Methods: To display the distribution of course of disease of the infectors who had close contacts with COVID-19 cases from January 1 to March 15, 2020 in Guangdong Provincial, the models of Lognormal, Weibull and gamma distribution were applied. A descriptive analysis was conducted on the basic characteristics and epidemiological parameters of course of disease. Results: In total, 515 of 11 580 close contacts were infected, with an attack rate about 4.4%, including 449 confirmed cases and 66 asymptomatic cases. Lognormal distribution was fitting best for latent period, incubation period, pre-symptomatic infection period of confirmed cases and infection period of asymptomatic cases; Gamma distribution was fitting best for infectious period and clinical symptom period of confirmed cases; Weibull distribution was fitting best for latent period of asymptomatic cases. The latent period, incubation period, pre-symptomatic infection period, infectious period and clinical symptoms period of confirmed cases were 4.50 (95%CI:3.86-5.13) days, 5.12 (95%CI:4.63-5.62) days, 0.87 (95%CI:0.67-1.07) days, 11.89 (95%CI:9.81-13.98) days and 22.00 (95%CI:21.24-22.77) days, respectively. The latent period and infectious period of asymptomatic cases were 8.88 (95%CI:6.89-10.86) days and 6.18 (95%CI:1.89-10.47) days, respectively. Conclusion: The estimated course of COVID-19 and related epidemiological parameters are similar to the existing data.
COVID-19 ; Cohort Studies ; Contact Tracing ; Humans ; Incidence ; Prospective Studies

Collagen is a macromolecular protein constituting the extracellular matrix of animal connective tissue, which has been widely used and developed in fields of biomedicine, tissue engineering, food, and cosmetics. Due to its advantages such as abundant sources and good biocompatibility, low immunogenicity, and degradability, collagen can be used as a dressing or tissue engineering scaffold for wound repair. According to the source of materials, collagen can be divided into natural collagen and recombinant collagen. Natural collagen is mainly extracted directly from mammals and fish; recombinant collagen is obtained based on genetic engineering technology, and its sources include recombinant expression systems of microorganisms, animals, and plants. This paper summarizes the sources of collagen, and the roles, advantages, and disadvantages of different sources of collagen in wound repair, the particularity and superiority of collagen combined with three-dimensional printing technology in wound repair, the impact of market norms of China's collagen industry on the field of wound repair, and explains the precautions for the development of collagen-related products, aiming to provide new ideas for selecting a suitable source of collagen for wound repair.
Animals ; Collagen/metabolism* ; Wound Healing ; Tissue Engineering ; Tissue Scaffolds ; Cosmetics ; Mammals/metabolism*

As a cutting-edge technology of tissue engineering, three-dimensional bioprinting can accurately fabricate biomimetic tissue, which has made great progress in the field of hard tissue printing such as bones and teeth. Meanwhile, the research on soft tissue bioprinting is also developing rapidly. This article mainly discussed the development progress in various bioprinting technologies and supporting equipment including printing software, printing hardware, supporting consumables, and bioreactors for soft tissue three-dimensional bioprinting, and made a prospect for the future research and development direction of soft tissue three-dimensional bioprinting.
Bioprinting/methods* ; Biocompatible Materials ; Printing, Three-Dimensional ; Tissue Engineering ; Research

Colectomy ; Colorectal Neoplasms/surgery* ; Humans ; Laparoscopy ; Treatment Outcome

Objective:To study and compare the prognosis of different pathological subtypes of renal cell carcinoma (RCC).Methods:Clinicopathological and prognostic data of 1 346 cases of postoperative renal cell carcinoma during July 2002 to June 2014 in West China Hospital were collected retrospectively.There were 839 males and 507 females, aged (55.1±13.4)years, including 1 120 cases of clear cell RCC, 62 cases of papillary RCC, 79 cases of chromophobe RCC and 85 cases of the other pathological types respectively. ECOG 0 and ≥1 were 911 and 435 cases, with; T 1, T 2, T 3 and T 4 of 1 019, 177, 102 and 48 cases respectively; WHO nuclear grade for well, intermediate, poor differentiation and unknown were 587, 530, 85 and 144 cases separately.Tumor size <5cm, 5-10cm, ≥10cm and unknown were 685, 541, 104 and 16 cases.Combined with necrosis or sacromatoid differentiation were 200/1 146 and 27/1 319 cases separately. Meanwhile, data of 80 439 cases from Surveillance, Epidemiology, and End Results Program (SEER) were also collected.There were 51 371 males and 29 068 females, aged (60.9±12.4) years; , with 66 261, 8 680, 5 022 and 476 cases of White, Black, Asian, American native, or unknown race separately. There were 62 600 of clear cell RCC, 12 170 of papillary RCC, 4 354 of chromophobe RCC and 1 315 of other pathological types, with T 1, T 2, T 3 and T 4 of 55 332, 8 687, 15 516 and 904 cases respectively; WHO nuclear grade for well, intermediate and poor differentiation were 52 323, 22 700 and 5 416 cases separately.Tumor size <5cm, 5-10cm, ≥10cm were 46 741, 25 760 and 7 938 cases respectively. Kaplan-Meier survival analysis were performed on these two group of cases, with different factors between subgroups (gender, age, pathological types, tumor stage, size and nuclear grade) evaluated by log-rank test. To evaluate accuracy of outcome prediction models of SSIGN, Leibovich and UISS score, concordance index of these models were evaluated. Results:In 1 346 cases of our cohort, those with chromophobe RCC were well prognostic, survival were relatively better in clear cell RCC than that of papillary RCC, and worst prognosis were demonstrated in those with other types of RCC (5 year overall survival rate: 97.5%, 87.9%, 79.7% and 68.4% separately). Poor prognosis were seen in those older than 50 years, with poor T stage or nuclear grade, large tumor size and tumors with necrosis or sacromatoid differentiation ( P<0.05). In 80 439 seer cases, the best prognosis was also seen in chromophobe RCC and the worst in other type of RCC separately (5 year overall survival rate: 96.3% and 85.3%). In addition, longer survival was seen in papillary RCC than clear cell RCC (5 year overall survival rate: 92.5% and 88.9%). However, similar results with our cohort were seen in Asian and American native subgroup of SEER cases (95.1%, 88.6%, 86.7%, 80.2% for chromophobe, clear cell, papillary and other types of RCC respectively). Poor prognosis were seen in those older than 50 years, males, Asian/ American Indian, poor T stage or nuclear grade and large tumor size ( P<0.05). Concordance index for SSIGN, Leibovich and UISS models in our cohort were 0.763-0.781, 0.725-0.752 and 0.641-0.660, respectively. The chromophobe RCC subgroup was relative better based on predictive value of prognosis models(c-index of UISS of 0.670-0.781, SSIGN and Leibovich of 0.733-0.903). Conclusions:In Asian RCC population, prognosis of chromophobe RCC is best, clear cell RCC is slightly better than papillary RCC, and the prognosis of other types of RCC is the worst. Concordance index of SSIGN and Leibovich in our cohort were higher than that of UISS, and the use value for predictive model was better in the chromophobe RCC subgroup.

Consensus ; Critical Illness ; Humans ; Serum Albumin ; Serum Albumin, Human

Aortic Valve/surgery* ; Aortic Valve Stenosis/surgery* ; China/epidemiology* ; Heart Valve Prosthesis Implantation ; Humans ; Severity of Illness Index ; Treatment Outcome

Since December 2019, novel coronavirus pneumonia (NCP) has been reported in Wuhan, Hubei Province, and spreads rapidly to all through Hubei Province and even to the whole country. The virus is 2019 novel coronavirus (2019-nCoV), never been seen previously in human, but all the population is generally susceptible. The virus spreads through many ways and is highly infectious, which brings great difficulties to the prevention and control of NCP. Based on the needs of orthopedic trauma patients for emergency surgery and review of the latest NCP diagnosis and treatment strategy and the latest principles and principles of evidence-based medicine in traumatic orthopedics, the authors put forward this expert consensus to systematically standardize the clinical pathway and protective measures of emergency surgery for orthopedic trauma patients during prevention and control of NCP and provide reference for the emergency surgical treatment of orthopedic trauma patients in hospitals at all levels.

TSCI have dyskinesia and sensory disturbance that can cause various life-threaten complications. The patients with traumatic spinal cord injury (TSCI), seriously affecting the quality of life of patients. Based on the epidemiology of TSCI and domestic and foreign literatures as well as expert investigations, this expert consensus reviews the definition, injury classification, rehabilitation assessment, rehabilitation strategies and rehabilitation measures of TSCI so as to provide early standardized rehabilitation treatment methods for TSCI.