Acute or chronic wounds are common clinical problems. Collagen, with advantages including rich sources, impeccable biocompatibility, and inherent biodegradability, has been widely used in fundamental research and clinical treatment of wound repair with broad prospects of clinical applications. This article provided a brief overview of the role of collagen in various biological processes related to wound healing and also outlined the sources of collagen. Furthermore, the article summarized the application and recent research advancements of collagen-based wound dressings in the field of wound repair.

Objective To evaluate the molluscicidal effects and costs of spraying 20% suspension concentrate of pyricloben-zuron sulphate (SCPS) with drones against Pomacea canaliculata in paddy environments, so as to provide insights into the extensive applications of pyriclobenzuron against P. canaliculata. Methods On July 2022, a paddy field was selected from Nanchang City, Jiangxi Province as the study area, and 72 independent rectangular plots measuring 2 m × 1 m were allocated in the study area, with 1 m interval between each plot, and 20 P. canaliculata snails gently placed in each plot. The activity of 25% wettable powder of pyriclobenzuron sulphate (WPPS) by manual spraying at doses of 0.50, 1.00, 2.00 g/m² and 4.00 g/m² against P. canaliculata was tested in 54 plots, and manual spraying of 50% wettable powder of niclosamide ethanolamine salt (WPNES) at a dose of 0.10 g/m² served as a chemical control, while manual spraying of the same volume of clean water served as a blank control, with 9 plots in each group. The activity of SCPS against P. canaliculata was tested in the remaining 18 plots. Based on the molluscicidal tests of WPPS, the molluscicidal effect of SCPS by manual spraying at doses of 0.20, 0.30, 0.40 g/m² and 0.50 g/m² against P. canaliculata was evaluated, and manual spraying of WPNES at a dose of 0.10 g/m² served as a chemical control, while manual spraying of the same volume of clean water served as a blank control, with three plots in each group. On July 2023, 14 paddy fields with a mean living P. canaliculata density of > 5 snails/m² were selected from Yujiang District, Yingtan City, Jiangxi Province for molluscicidal tests. Based on the molluscicidal effect of pyriclobenzuron against P. canaliculata in plots, the molluscicidal effects of WPPS by manual spraying at doses of 0.25, 0.50 g/m² and 1.00 g/m² and manual applications of WPPS at dose of 0.25, 0.50, 1.00 g/m² and 2.00 g/m² mixed with soil were tested, and manual spraying of 0.10 g/m² WPNES served as a chemical control group, while manual spraying of the same volume of clean water served as a blank control, with one paddy field in each group. Based on the effect of pyriclobenzuron against P. canaliculata in plots, the activity of SCPS sprayed with drones at doses of 0.25 g/m² and 0.50 g/m² mixed in water at 2 kg/667 m² and 4 kg/667 m² was tested against P. canaliculata, and spraying of the same volume of clean water with drones served as a blank control. All P. canaliculata snails were captured 3 days and 7 days following chemical treatment in plots and paddy fields and identified for survival, and the mortality and corrected mortality of P. canaliculata snails were estimated. In addition, the areas of chemical treatment, amount of molluscicide use and labor costs of chemical treatment were estimated in molluscicidal tests in paddy fields, and the costs of chemical treatment for an area covering 667 m² by drones and manual applications were calculated. Results The mortality of P. canaliculata snails was all 100% in plots 3 days and 7 days following spraying WPPS at doses of 0.50, 1.00, 2.00 g/m² and 4.00 g/m², and the mortality rates of P. canaliculata snails were 66.67% to 100.00% 3 days post-treatment with SCPS at various doses (χ² = 277.897, P < 0.05) and 76.67% to 100.00% 7 days post-treatment (χ² = 274.206, P < 0.05). The mortality rates of P. canaliculata snails were 98.19% to 100.00% 3 days post-treatment with WPPS at various doses in paddy fields. There was a significant difference in the mortality of P. canaliculata snails among WPPS treatment groups and controls (χ² = 270.778, P < 0.05), and there were no significant differences between WPPS treatment groups and the chemical control group (all P values > 0.05), while there were significant differences in the mortality of P. canaliculata snails between WPPS treatment groups and the blank control group (all P values < 0.05). The mortality rates of P. canaliculata snails were 89.83% to 95.31% 3 days post-treatment with SCPS at various doses sprayed with drones, and there was a significant difference in the mortality of P. canaliculata snails among SCPS treatment groups and the blank control group (χ² = 1 132.892, P < 0.05). There were no significant differences in the mortality of P. canaliculata snails among SCPS treatment groups or water mixture groups (all P values > 0.05), and there were significant differences in the mortality of P. canaliculata snails between SCPS treatment groups and the blank control group (all P values < 0.05). The mortality rates of P. canaliculata snails were 94.62% to 100.00% 7 days post-treatment with SCPS at various doses sprayed with drones, and there was a significant difference in the mortality of P. canaliculata snails among SCPS treatment groups and the blank control group (χ² = 1 266.932, P < 0.05), with the highest mortality found following spraying 0.50 g/m² SCPS mixed in 2 kg/667 m² water with drones (P < 0.05). The costs of P. canaliculata snail control by drones and manually were 35.85 Yuan/667 m² and 43.33 Yuan/667 m²; however, the snail control efficiency was 6.67 times higher by drones than by manual applications. Conclusions SCPS sprayed with drones is highly active against P. canaliculata snails in paddy fields. SCPS sprayed with drones is highly efficient and low in cost for P. canaliculata snail control in paddy fields, beaches and river courses.

Objective:To investigate the value of systemic inflammatory response syndrome (SIRS), pediatric sequential organ failure assessment (pSOFA) and pediatric critical illness score (PCIS) in predicting mortality of pediatric sepsis in pediatric intensive care units (PICU) from Southwest China.Methods:This was a prospective multicenter observational study. A total of 447 children with sepsis admitted to 12 PICU in Southwest China from April 2022 to March 2023 were enrolled. Based on the prognosis, the patients were divided into survival group and non-survival group. The physiological parameters of SIRS, pSOFA and PCIS were recorded and scored within 24 h after PICU admission. The general clinical data and some laboratory results were recorded. The area under the curve (AUC) of the receiver operating characteristic curve was used to compare the predictive value of SIRS, pSOFA and PCIS in mortality of pediatric sepsis.Results:Amongst 447 children with sepsis, 260 patients were male and 187 patients were female, aged 2.5 (0.8, 7.0) years, 405 patients were in the survival group and 42 patients were in the non-survival group. 418 patients (93.5%) met the criteria of SIRS, and 440 patients (98.4%) met the criteria of pSOFA≥2. There was no significant difference in the number of items meeting the SIRS criteria between the survival group and the non-survival group (3(2, 4) vs. 3(3, 4) points, Z=1.30, P=0.192). The pSOFA score of the non-survival group was significantly higher than that of the survival group (9(6, 12) vs. 4(3, 7) points, Z=6.56, P<0.001), and the PCIS score was significantly lower than that of the survival group (72(68, 81) vs. 82(76, 88) points, Z=5.90, P<0.001). The predictive value of pSOFA (AUC=0.82) and PCIS (AUC=0.78) for sepsis mortality was significantly higher than that of SIRS (AUC=0.56) ( Z=6.59, 4.23, both P<0.001). There was no significant difference between pSOFA and PCIS ( Z=1.35, P=0.176). Platelet count, procalcitonin, lactic acid, albumin, creatinine, total bilirubin, activated partial thromboplastin time, prothrombin time and international normalized ratio were all able to predict mortality of sepsis to a certain degree (AUC=0.64, 0.68, 0.80, 0.64, 0.68, 0.60, 0.77, 0.75, 0.76, all P<0.05). Conclusion:Compared with SIRS, both pSOFA and PCIS had better predictive value in the mortality of pediatric sepsis in PICU.

Complicated crown root fracture is a serious combined fracture of the enamel,dentin,and cementum in dental trauma.The treatment method is complicated.During the procedure,the condition of pulp,periodontal,and tooth body should be thoroughly evaluated,and a multidisciplinary approach combined with sequential treatment is recom-mended.This case reported the different treatment and repair processes of one case of two affected teeth after complicat-ed crown root fracture of upper anterior teeth,including regrafting of broken crown after flap surgery at the first visit,di-rect resin repair to remove broken fragments,and pulp treatment and post-crown repair at the second visit.After 18 months of follow-up,the preservation treatment of the affected teeth with complicated crown root fracture was achieved.Therefore,fragment reattachment and post-crown restoration are feasible treatment options for children with complicated crown root fracture.

Objective:To provide references for the clinical popularization of stainless steel crowns by analyzing the clinical application and affecting factors of stainless steel crowns used in primary molars based on a questionnaire survey.Methods:Pediatric dentists from all over the country in June to December 2013 and June to December 2022 were selected to answer the survey questionnaire through the online or offline methods for analyzing the clinical application and influencing factors of stainless steel crowns used in primary molars.Results:A total of 712 and 580 questionnaires were distributed, and 608 and 512 valid questionnaires were recovered respectively in 2013 and 2022. The effective rates of the questionnaires were 85.4% and 88.3%. Among them, the usage rates of stainless steel crowns in 2013 and 2022 were 52.6% (320/608) and 78.1% (400/512) respectively, with a statistically significant difference (χ 2=78.68, P<0.001). The main reasons for not selecting stainless steel crowns in 2013 were high technical sensitivity [52.8% (152/288)], followed by the impact of crown edge on gingiva [50.0% (144/288)] and poor aesthetics [27.8% (80/288)], while in 2022 were the inadequate equipage in hospitals [53.6% (60/112)] and poor aesthetics [21.4% (24/112)]. The main reasons for choosing stainless steel crowns restoration were good protection effect, less tooth fracture [78.1% (250/320) in 2013 and 82.5% (330/400) in 2022], followed by low dropout rate [62.5% (200/320) in 2013 and 68.0% (272/400) in 2022]. The proportions of stainless steel crowns restoration for primary molars after root canal therapy were 51.3% (312/608) and 76.6% (392/512) respectively with statistically significant (χ 2=75.88, P<0.001). The proportions after pulp capping treatment for deep caries were 13.2% (80/608) and 53.1% (272/512) respectively, and the difference was statistically significant (χ 2=206.01, P<0.001). Conclusions:During the 10 years from 2013 to 2022, the technical sensitivity of stainless steel crowns had gradually decreased, and the application in China had gradually increased. However, some hospitals have not yet equipped, which limits the application of stainless steel crowns. Therefore, training efforts should be derived to promote the clinical popularization of stainless steel crowns.

Objective:To explore the related mechanisms of biological root resorption in decidual teeth by studying the biological effect of simulated occlusal force on the periodontal ligament stem cells (PDLSC) at different stages of root absorption.Methods:According to the tooth type and root absorption degree, healthy retained deciduous incisors and healthy first premolars that needed to be removed for orthodontic treatment were collected and divided into three groups with six teeth in each group: the deciduous unabsorbed group (UN group), the absorbed group (R group) and the permanent teeth group (P group). PDLSC was isolated from periodontal ligament and cultured. PDLSC of three groups were loaded with dynamic pressure of 0-45, 0-90, 0-135, 0-180, 0-225 and 0-270 kPa, respectively. The proliferation ability was detected by cell counting kit-8 (CCK-8) technique on day 1 to day 7, respectively. The apoptosis levels of PDLSC after loading with dynamic pressure of 0-45, 0-90, 0-135, 0-180 and 0-225 kPa were observed by the flow cytometry. The changes of microfilaments were observed by fibrous actin (F-actin) staining after the cytokeleton was subjected to dynamic pressure of 0-90 kPa.Results:PDLSC of three groups exhibited various proliferation abilities to dynamic pressure. The A values in the UN group and R group were significantly higher than those in the P group and the difference was statistically significant ( P<0.05). However, there was no significant difference between the UN group and the R group ( P>0.05). The A values of PDLSC in UN group and R group under dynamic pressures of 0-45, 0-90, 0-135 and 0-180 kPa had no statistical significance compared with the control group unloading dynamic pressure ( P>0.05). However, under 0-225 and 0-270 kPa dynamic pressures, the A values at the day 3 to day 7 were statistically significant ( P<0.05). The A values of PDLSC in P group under 0-45, 0-90, 0-135, 0-180 and 0-225 kPa dynamic pressures for 1 to 7 days were no statistically significant difference compared with the control group ( P>0.05). The A value in P group under the 0-270 kPa was statistically significant only on day 3 (1.386±0.131) and day 5 to day 7 (1.728±0.226, 2.029±0.168 and 2.263±0.210, respectively)( P<0.05). The result of apoptosis showed that the A values of PDLSC in UN group, R group and P group were significantly increased under 0-90, 0-135, 0-180 kPa and above dynamic pressures, respectively ( P<0.05) compared with the control group unloading dynamic pressure. Under 0-90 kPa dynamic pressure, F-actin fluorescence staining samples in three groups all showed green filaments which were arranged along the long axis of the cells in the R group and the P group, while some fibers in the UN group were closely arranged and promoted stress fiber assembly. Conclusions:The biological characteristics of PDLSC at different root absorption stages were changed when they were stimulated by mechanical stress, and PDLSC of the deciduous teeth at the root unabsorption stage were more sensitive to mechanical stress stimulation.

Objective: To study the influence of personality on the occurrence of dental trauma of school-aged children. Methods:The school-aged children with dental trauma who came to visit our department were randomly recruited. The Eysenck Personality Scale was used to test the subjects who met the inclusion criteria. Results: 306 children were included in the study. There was a statistically significant association between personality type and the number of traumatic teeth (P ＜ 0. 05) and the number of traumatic teeth in children with extroversion was higher than that of children with neutrality or introversion (P ＜ 0. 05) . Conclusion: Extroverted personality is a significant correlation factor affecting the severity of dental trauma in children, and it is of great significance to provide scientific guidance and warning for them to prevent tooth trauma.

Objective: To study the clinical reference pulpal blood flow(PBF) values detected by laser doppler flowmetry(LDF) in healthy young population and to analyze their possible affected factors. Methods: Undergraduate students at the age of 17-23 years were enrolled. PBF of 12-22 were detected by LDF based on the standard procedure. Difference of the test results between different sex was analyzed by T test and variance homogeneity test, and the correlation with age was analyzed by the chi-square test, and the difference between the different teeth was analyzed by the random group analysis. Results: 400 students(250 males and 150 females with the average age of 19. 83 years) met the inclusion criteria. The clinical reference values of PBF of different anterior teeth were obtained by the detection of LDF. For the same tooth, PBF values of females were higher than that of males (P＜ 0. 05). PBF values of different ages shared no statistical significance(P＞ 0. 05). For the same gender, PBF values of middle incisor were higher than that of lateral incisors(P＜ 0. 05). Conclusion: The determination of the clinical reference values of PBF detected by LDF may promote the clinical use of this technology.

Objective To construct two DNA vaccines based on two glycoprotein antigen segments of Xinjiang hemorrhagic fever virus (XHFV) and to evaluate the immune responses in BALB/c mice following vaccination.Methods Two recombinant expression plasmids pVAX1-GcⅠand pVAX1-Gc Ⅱ were constructed by inserting XHFV YL04057 strain Gc Ⅰ (1 229-1 349 aa) and Gc Ⅱ (1 443-1 566 aa) fragments into the eukaryotic expression vector pVAX1 and then were identify by restriction enzyme digestion and sequencing analysis.The recombinant expression plasmids were transfected into mice by hydrodynamics-based transfection.Immune responses induced in mice were evaluated by testing the proliferation of T cells with MTT,measuring serum antibody level with ELISA and detecting cytokines in the supernatant of spleen cell culture with ELISA kit.Results The recombinant expression plasmids were successfully constructed as indicated by the results of restriction enzyme digestion and sequencing analysis.Expression of Gc Ⅰ and Gc Ⅱ genes in mice liver tissues was detected.Antibody titers in mice immunized with pVAX1-GcⅠor pVAX1-Gc Ⅱ were higher than those in mice immunized with pVAX1.Compared with pVAX1,pVAX1-Gc Ⅱ significantly enhanced the proliferation of splenic T lymphocytes and the expression of IFN-γ (P<0.01).Conclusion The constructed two DNA vaccines for XHFV can induce specific humoral and cellular immune responses in mice.pVAX1-Gc Ⅱ is better than pVAX1-GcⅠin immunogenicity and protective efficacy,suggesting that it can be used as a promising candidate for the development of DNA vaccine for XHFV.

Objective To establish a small amount of acid ,microwave digestion‐atomic fluorescence spectrometer method was developed for the determination of arsenic and mercury in eggs at the same time .Methods The sample was digested with 1 ml HNO3 ,After digestion ,the sample was deoxidized with sulfocarbamide and vitamin C and then determined by AFs without dispel‐ling the acid .Results The sample was digested with 1 mL HNO3 ,After digestion ,the sample was deoxidized with sulfocarbamide and vitamin C and then determined by AFs without dispelling the acid .Conclusion The method is simple ,rapid and with little pol‐lution .The determination of arsenic and mercury in eggs by Atomic Fluorescence Spectrometry using microwave digestion were de‐veloped with satisfactory sensitivity ,accurate and precision .