ObjectiveTo explore the protective effect of polysaccharide from Inonotus obliquus （IOP） on lipopolysaccharide （LPS）-induced acute lung injury （ALI） in mice. MethodA total of 40 male C57BL/6 mice were randomly divided into normal group， model group， dexamethasone group， and high-dose and low-dose IOP groups， with eight mice in each group. The high-dose and low-dose IOP groups were administered intragastrically with IOP at 20 and 10 mg·kg^-1， respectively. The normal group and the model group were intragastrically administered with normal saline in equal volumes， and the dexamethasone group was intraperitoneally injected with dexamethasone phosphate injection of 30 mg·kg^-1 for 21 days. An ALI mouse model induced by LPS was constructed， and hematoxylin-eosin （HE） staining， immunofluorescence staining， and blood routine were used to detect pathological damage of lung tissue and blood cell content. Enzyme-linked immunosorbent assay （ELISA） and Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） were used to detect the expression levels of various inflammatory factors. Changes in gut microbiota and plasma differential metabolites in mice were detected using 16S rRNA sequencing and ultra-high performance liquid chromatography-quadrupole-time of flight tandem mass spectrometry （UPLC-Q-TOF-MS）. ResultCompared with the model group， the lung tissue lesions of ALI mice were significantly improved after IOP administration， and the spleen and thymus index were dramatically increased （P<0.05， P<0.01）. The ratio of wet-to-dry weight of lung tissue was sensibly decreased （P<0.05， P<0.01）， and the number of lymphocytes was substantially increased （P<0.05， P<0.01）. The number of neutrophils was markedly decreased （P<0.01）. The expression level of interleukin-6 （IL-6）， interleukin-8 （IL-8）， interleukin-1β （IL-1β）， nuclear factor-κB（NF-κB）， and nucleotide-binding oligomerization domain-like receptor 3 （NLRP3） decreased prominently （P<0.05， P<0.01） and the expression level of interleukin-10 （IL-10） increased memorably （P<0.01）. The 16S rRNA sequencing results show that IOP can regulate and improve intestinal microbial disorders. The UPLC-Q-TOF-MS results indicate that the treatment of ALI mice with IOP may involve pathways related to mitochondrial， sugar， and amino acid metabolism， such as nucleotide sugar metabolism， histidine metabolism， ubiquinone， and other terpenoid compound-quinone biosynthesis， as well as starch and sucrose metabolism. ConclusionThe improvement of lung tissue lesions and inflammatory response by IOP in ALI mice may be related to maintaining intestinal microbiota balance， regulating mitochondrial electron oxidation respiratory chain， as well as sugar and amino acid metabolism pathways， and affecting the production of related microbial metabolites and tricarboxylic acid cycle metabolites.

The United States is the country with the most pilot practices in value-based healthcare payment reform, and value-based purchasing (VBP) is one of its pilot projects. The authors introduced the basic situation and implementation effects of the pilot projects of VBP payment reform in the United States from the hospital and physician levels respectively, and analyzed the causes for their unsatisfactory implementation effects. Then, the authors proposed its enlightenments for China from such aspects as the construction of value-based medical payment index system, implementation of value-based medical payment reform, and management costs, to provide reference for the construction of high-quality value-based medical service system in China.

The pilot project for alternative payment models was originated from the implementation of the 2010 Affordable Care Act in the United States, which aimed to establish a new payment mode to replace the traditional payment based on service fees, thereby achieving the goals of ensuring healthcare quality, reducing healthcare costs, and improving healthcare equity. The pilot projects of alternative payment models included two types: accountable care organizations and bundled payments for care improvement. The authors introduced their profile and implementation effects, analyzed the causes of the current implementation effects, and then proposed enlightenments for the value-based medical payment reform in China, with the aim of providing reference for the construction of a high-quality value based medical service system in China.

Objective:To explore the genetic basis for a patient with factor XIII (FXIII) deficiency.Methods:All exons of the F13A1 and F13B genes were amplified by PCR and sequenced directly. The sequencing was performed with a reverse primer if a variant was found. Conservation of variant site was analyzed by the ClustalX software. Four online bioinformatic software including MutationTaster, PolyPhen-2, PROVEAN and SIFT were used to predict the function of the mutation site. The Swiss-PdbViewer software was applied to analyze the changes in the protein model and intermolecular force. Results:The proband was found to harbor a novel c. 515G>C (p.Arg171Pro) variant of the F13A1 gene. The corresponding amino acid Arg171 is conserved among homologous species. Bioinformatic analysis indicated that Arg171Pro variant may affect the protein function. Protein model analysis showed that in the wild-type, there is one hydrogen bond between Arg171 and Pro27; one hydrogen bond between Arg171 and Thr28; two hydrogen bonds between Arg171 and Glu102. When Arg171 was mutated to Pro171, the three hydrogen bonds between Arg171 and Pro27, Glu102 are all disappeared and formed a new benzene ring which might affect the stability of the protein structure. No variant was found in the F13B gene. Conclusion:The Arg171Pro variant may account for the decreased FXIII level. Above finding has enriched the spectrum of F13A1 gene variants.

Objective:To explore the value of using metagenomic next-generation sequencing (mNGS) technology to detect pathogens in patients with burns and patients with acute or chronic wounds.Methods:A retrospective observational study was conducted. From March 2019 to June 2020, 11 patients with burns and patients with acute or chronic wounds (including 10 males and 1 female, aged 23 to 85 years) in the Fourth Medical Center of PLA General Hospital met the inclusion criteria and were recruited. A total of 23 specimens were collected, including 6 whole blood specimens, 1 skin tissue specimen, 1 drained pus specimen, and 15 wound secretion swab specimens. Each specimen was divided into two parts, which were subjected for pathogen detection using microbial culture method and mNGS method, respectively. The number and types of pathogens detected by the 2 methods and the relative abundance detected by the mNGS method were recorded, and the consistency of the two methods were compared. Data were statistically analyzed with paired Wilcoxon rank sum test.Results:With the microbial culture method, no pathogen was detected in 5 of the 23 specimens, while 35 pathogens were detected in the remaining 18 specimens, belonging to 9 species of bacteria and 2 species of fungi. Five specimens had one pathogen while 9 specimens had 2 pathogens and 4 specimens had 3 pathogens detected in each specimen. With the mNGS method, no pathogen was detected in one of the 23 specimens, while 75 pathogens were detected in the remaining 22 specimens, belonging to 28 species of bacteria, 3 species of fungi, and 3 species of viruses. Eight specimens had one pathogen, 5 specimens had 2 pathogens, 2 specimens had 3 pathogens, 3 specimens had 4 pathogens, 2 specimens had 6 pathogens, and 1 specimen had 7 pathogens, and 1 specimen had 20 pathogens detected in each specimen. The number of pathogens detected in each specimen by microbial culture method was 2 (1, 2) types, which was significantly less than 2 (1, 4) types by mNGS method ( Z=3.359, P<0.01). In 5 specimens, no bacteria were detected by microbial culture method but mNGS method detected bacteria in 2 specimens and virus in 2 different specimens. The mNGS method detected two or more types of bacteria in 13 specimens, the relative abundance of bacteria with the 1st relative abundance ranking ranged from 28.8% to 95.9% in each specimen. Of the 23 specimens detected by two detection methods, 7 specimens (30.4%) showed identical detection results, 5 specimens (21.7%) showed totally different detection results, and 11 specimens (47.8%) had partially consistent detection results. Conclusions:Compared with the traditional microbial culture method, the mNGS method has higher detection sensitivity and stronger capacity to detect pathogens, and can determine the relative abundance of pathogens in mixed infections. As a supplement to the culture method, the mNGS method is expected to play an important role in the diagnosis of infectious pathogens in burns and acute or chronic wounds.

From July 2018 to April 2019, 10 patients (8 males and 2 females, aged 5 to 53 years) who need skin grafting with 17 hands were admitted to the Fourth Medical Center of PLA General Hospital. The method of glove bandaging was used for wound hemostasis in skin grafting. After the initial hemostasis, sterile latex gloves were used as the inner cover of hand, and then pressure-wrapped with gauze. After 20 minutes, the gauze and gloves were removed in order from the near to the far, then thorough hemostasis was conducted again, and finally skin grafting was performed. The use of gloves as inner cover can avoid the adhesion of gauze fibers to the wound surface, so that it will not cause small blood vessels to re-bleed when the gauze is removed, therefore reducing the excessive use of electrocoagulation and secondary damage to the wound. As a result, blood loss can be reduced and hemostatic time can be shortened.

Objective: To explore the surgical methods for children with contracture deformity on hands after burn. Methods: From January 2014 to January 2018, 33 pediatric patients, a total of 42 hands with scar contracture deformities were reviewed. There were 24 males and 9 females, aged from 11 months to 6 years and 7 months. Among them, 20 hands were volar metacarpophalangeal joint contractures, 9 were volar interphalangeal joint contractures, 7 were dorsal metacarpophalangeal joint contractures (3 claw-shaped hands), 3 were hand back contractures, and 3 were palm contractures. Of the 42 hands, 36 hands were repaired with full-thickness skin grafts or split-thickness skin grafts, after the removal of contracted scar, and 6 hands were repaired with abdominal skin flaps, due to the tendon or bone exposure after the scar removal. Results: Skin grafts on 31 hands were all survived after 2 weeks. However, the survival area of 3 skin grafts was about 90%, and 2 skin grafts survived about 80%. All of them healed well after dressing changing. The 6 hands repaired with abdominal skin flap healed well too. After 1-2.5 years of follow-up, finger scar contracture occurred in 4 hands with skin grafting, and they were performed scar excision and sheet skin grafting. Three hands were treated with Z-plasty, due to web space contracture. The function of other hands were normal, without contracture or deformity. The skin color and texture were similar to the surrounding skin, with limited pigmented. Scars on the edge of skin grafts was not obvious. Patients and their families were satisfied. Conclusions The sheet skin graft is the main method for postburn scar contracture in children′s hands. The abdominal skin flap should be considered, if tendon or bone is exposed, especially for large wound or multiple sites.

Objective: To observe the clinical effects of stage-Ⅱ Meek skin grafting on adipose tissue after tangential excision in patients with extensive deep burns, and to explore the functional mechanism. Methods: The medical records of 26 extensively burned patients who met the inclusion criteria and were admitted to the Department of Burns and Plastic Surgery of the Fourth Medical Center of PLA General Hospital from May 2015 to December 2017 were retrospectively analyzed. According to the treatment methods, 14 patients were enrolled in stage-Ⅰ skin grafting group (10 males and 4 females, aged 27 to 75 years), and 12 patients were enrolled in stage-Ⅱ skin grafting group (10 males and 2 females, aged 31 to 76 years). Patients in the 2 groups all underwent debridement of tangential excision, and their healthy adipose tissue was preserved. Meek skin grafting was performed just after tangential excision in patients in stage-Ⅰ skin grafting group. In patients in stage-Ⅱ skin grafting group, porcine acellular dermal matrix (ADM) was applied to cover the wound after tangential excision, and 3 days later, it was removed and Meek skin grafting was performed. The times of complement skin grafting and the wound basic healing time of patients in the 2 groups were observed and recorded. In the stage-Ⅱ skin grafting group, the adipose tissue of patients were taken from the wound center immediately after tangential excision and immediately after the removal of porcine ADM, for the observation of structure of the fault surface of adipose tissue through hematoxylin and eosin staining and microvessel density (MVD) through immunohistochemical staining. Data were processed with independent sample t test and Fisher′s exact probability test. Results: (1) The times of complement skin grafting of patients in stage-Ⅱ skin grafting group was (1.83±0.17) times, which was obviously less than (3.36±0.63) times in stage-Ⅰ skin grafting group (t=2.19, P<0.05). The wound basic healing time of patients in stage-Ⅱ skin grafting group was (35.1±2.3) d, which was obviously shorter than (48.8±4.9) d in stage-Ⅰ skin grafting group (t=2.27, P<0.05). (2) Immediately after tangential excision, the intercellular substance was few between the adipose cells in adipose tissue of patients in stage-Ⅱ skin grafting group. Immediately after the removal of porcine ADM, there was regenerated granulation tissue in the intercellular space of adipose cells of adipose tissue of patients in stage-Ⅱ skin grafting group. Immediately after tangential excision, the MVD of adipose tissue of patients in stage-Ⅱ skin grafting group was 20.2±1.3 under per 400-time field, which was obviously less than 32.2±1.9 under per 400-time field immediately after the removal of porcine ADM (t=-5.38, P<0.01). Conclusions Meek skin grafting on the adipose tissue in stage-Ⅱ surgery after tangential excision could reduce the times of complement skin grafting and shorten wound healing time of patients with extensive deep burns. The mechanism may be related to the improvement of the recipient condition of adipose tissue.

Objective: To observe the effects of minimally invasive tangential excision in treating deep partial-thickness burn wounds on trunk and limbs in pediatric patients in the early stage post burn. Methods: Clinical data of 40 children with deep partial-thickness burn wounds on trunk and limbs, admitted to our burn ward from January 2016 to June 2017, conforming to the study criteria, were retrospectively analyzed. They were divided into conventional treatment group (CT, n=19) and minimally invasive tangential excision group (MITE, n=21) according to the different treatments. The patients in group CT were treated with eschar-reserving therapy firstly. When tangential excision was performed, the roller knife was used, and no necrotic tissue left on the wound bed was considered the proper depth of excision. Razor-thickness skin grafting was performed to cover the wound when adipose tissue exposed markedly after tangential excision. Dressing change was performed within 48 h after the operation and repeated every 2 days. Unhealed wounds were covered by razor-thickness skin grafting. The patients in group MITE were treated with tangential excision in the early stage post burn. The tangential excision was operated with electric dermatome, and the thickness was set at 0.1 mm to excise the surface of eschar until the sporadic punctate hemorrhage on wound surface was observed and some necrotic tissue was left on the wound bed. Porcine acellular dermal matrix was applied after tangential excision. The first dressing change was often performed about 1 week after the operation. Razor-thickness skin grafting was performed to cover the unhealed wounds. The length of wound healing, high fever, antibiotic usage, and hospital stay, times of later operation, and hospitalization expenses of patients in the 2 groups were recorded. The excisional eschar and wound bed tissue of patients in group MITE were harvested for pathological observation. Data were processed with t test and Fisher′s exact probability test. Results: (1) There were no statistically significant differences in length of high fever and length of hospital stay and hospitalization expenses between patients in the 2 groups (t=-1.67, -1.93, 0.31, P>0.05). The lengths of wound healing [(24.8±2.5) d] and antibiotic usage [(4.4±0.7) d] of patients in group MITE were significantly shorter than those in group CT [(33.3±2.5) and (7.0±0.7) d, t=-2.44, -2.44, P<0.05], and times of later operation of patients in group MITE [(0.29±0.14) times] were significantly less than those in group CT [(0.79±0.21) times, t=-2.03, P<0.05]. (2) The thickness of the excisional eschar of patients in group MITE was about 150 μm. The eschar has epidermis and upper dermis. Some necrotic tissue was left on the wound bed. Conclusions The treatment for pediatric deep partial-thickness burn wounds on trunk and limbs with minimally invasive tangential excision using electric dermatome in the early stage post burn can accelerate wound healing, shorten length of antibiotic usage, and reduce times of later operations.

Through the discussion of the basic components and development of experimental animal ethical education and the effect of strengthening animal ethical education on comprehensive experimental teaching of preclinical medicine,this paper analyzed the status of animal ethical education in the comprehensive experimental teaching of preclinical medicine,and pointed out the medical students' existing problems of animal ethical education in the comprehensive experimental teaching of preclinical medicine,including that they didn't understand the real meaning of animal experiments and the experimental attitude was not correct;they ignored the feelings of experimental animals and increased the pain of experimental animals;school did not provide specialized animal ethics education and related animal ethics research was inadequate.And this paper put forward the countermeasures aiming at the as follows,teachers need to expound animal ethics knowledge before the experiment,strengthen experimental operation management and standardize the operation of animal experiments;the teachers should teach by personal example and verbal instruction and pay attention to animal ethical education in the experimental teaching process.