1.Association between obesity and osteoporosis:a two-sample Mendelian randomization analysis
Qunzhang ZHAN ; Yuling ZHANG ; Yuxin HAN ; Jiazhen LYU ; Xiaoxia ZHENG ; Chongzheng QU
Chinese Journal of Tissue Engineering Research 2024;28(27):4319-4324
BACKGROUND:Numerous clinical studies have suggested a close relationship between obesity and osteoporosis,but whether there is a genetic causal effect between obesity and osteoporosis remains unclear. OBJECTIVE:To explore the association between obesity and osteoporosis using summary data from a large-scale genome-wide association study(GWAS)through Mendelian randomization analysis. METHODS:Obesity data were derived from summary statistics of the Genetic Investigation of Anthropometric Traits(GIANT)and the UK Biobank(UKBB).Osteoporosis data were obtained from the Genetic Factors for Osteoporosis(GeFOS)consortium,including two bone density phenotypes:total body bone mineral density(BMD)and heel BMD.The inverse variance-weighted method was the primary analysis,with the Mendelian randomization method based on Egger regression(MR-Egger)and weighted median method as supplementary approaches to calculate the causal association between genetic variations related to obesity and osteoporosis.Sensitivity analyses were conducted to validate the reliability of the results.Heterogeneity was assessed using Cochran's Q test.Horizontal pleiotropy was assessed through the MR-Egger intercept test.Leave-one-out analysis was performed to evaluate the potential influence of single nucleotide polymorphisms on the combined inverse variance-weighted estimates. RESULTS AND CONCLUSION:(1)Impact of obesity on osteoporosis:In addition to body mass index and forearm BMD,body mass index,waist-to-hip ratio,body mass index-adjusted waist-to-hip ratio,and whole-body body mass index,heel BMD,forearm BMD,lumbar spine BMD,and femoral neck BMD were causally related to each other.Further Meta-analysis revealed that obesity increased the risk of BMD(odds ratio=1.07,95%confidence interval:1.03-1.12,P<0.01).(2)Impact of osteoporosis on obesity:Apart from arm BMD and lumbar spine BMD as exposure factors showing causal relationships with obesity,other datasets indicated no causal effect between total body BMD,heel BMD,femoral neck BMD,and obesity.Additional meta-analysis demonstrated that BMD did not increase the risk of obesity(odds rate=0.99,95%confidence interval:0.98-1.01,P<0.01).There is a causal relationship between obesity and osteoporosis,suggesting that obesity may be a risk factor for osteoporosis.However,no causal association is found between osteoporosis and obesity.
2.Serum hepatitis B virus pregenomic RNA profiles in patients with chronic hepatitis B on long-term antiviral therapy
Jiali PAN ; Hao LUO ; Xiaxia ZHANG ; Yifan HAN ; Hongyu CHEN ; Zhan ZENG ; Xiaoyuan XU
Chinese Journal of Hepatology 2024;32(1):16-21
Objective:To explore the clinical changes in levels of the new clinical marker serum hepatitis B virus (HBV) pregenomic RNA (pgRNA) in patients with chronic hepatitis B (CHB) with long-term antiviral therapy.Methods:100 CHB cases who were initially treated with nucleos(t)ide analogues (NAs) at Peking University First Hospital were included. The levels of alanine aminotransferase (ALT), HBV DNA, hepatitis B e-antigen (HBeAg), and hepatitis B surface antigen (HBsAg) during the follow-up period were measured. The TaqMan-based real-time quantitative PCR method was used to detect serum HBV pgRNA levels. The independent sample t-test and Mann-Whitney U test were used to compare continuous variables between groups, while Pearson's χ2 test and Fisher's exact test were used to compare categorical variables. Results:HBV pgRNA levels decreased significantly in patients who developed virological responses at 48 weeks ( n = 54) during subsequent treatment compared to those who did not ( n = 46). The HBV pgRNA level was lower in HBeAg-positive patients than in HBeAg-negative patients ( P < 0.05 or P < 0.01). Patients with higher HBV DNA and HBeAg-positivity levels at baseline had a higher HBV pgRNA level following antiviral therapy. There was no statistically significant difference in HBV pgRNA levels in patients with different HBV pgRNA levels at baseline after antiviral therapy. There was no correlation between serum HBV pgRNA and HBsAg at baseline, but there was a correlation after long-term antiviral therapy, while there was a weak correlation between HBV pgRNA and HBsAg at the fifth and ninth years of antiviral therapy ( r = 0.262, P = 0.031; r = 0.288, P = 0.008). Conclusion:HBV pgRNA levels were higher with higher HBV activity in CHB patients with long-term antiviral therapy.
3.Strategy to Guide Revascularization of Non-culprit Lesions in Patients With STEMI:State of Art and Future Prospects
Yingyang GENG ; Yin ZHANG ; Chujie ZHANG ; Han ZHANG ; Jingjing XU ; Ying SONG ; Cheng CUI ; Pei ZHU ; Lijian GAO ; Zhan GAO ; Jue CHEN ; Lei SONG
Chinese Circulation Journal 2024;39(3):301-305
Acute ST-segment elevation myocardial infarction with multivessel disease is one of the high-risk types of coronary heart disease.Early opening of infarct-related artery and reperfusion of myocardium could significantly reduce the mortality in acute phase.However,the presence of non-culprit lesions in non-infarct-related arteries is still at risk and has an important impact on the long-term prognosis of patients.It remains controversial on how to precisely evaluate the clinical significance and revascularization value of non-culprit lesions.This article aims to review the research status and progress of guidance strategies of non-culprit lesion revascularization in patients with ST-segment elevation myocardial infarction and multivessel disease.
4.Bacterial community diversity in human Demodex mites
Renren HAN ; Dacun ZHANG ; Lan WANG ; Feifan TANG ; Jiacheng CAO ; Jingxuan WANG ; Xiaodong ZHAN ; Shengli GU
Chinese Journal of Schistosomiasis Control 2024;36(2):174-178
Objective To investigate the bacterial community diversity in human Demodex mites, so as to provide insights into unraveling the role of human Demodex mites in them caused infectious diseases. Methods From June to July 2023, Demodex mites were collected from the faces of college students in a university in Wuhu City using the adhesive tape method, and the V4 region of 16S ribosomal RNA (16S rRNA) gene and the internal transcribed spacer (ITS) gene of nuclear ribosomal DNA were amplified on an Illumina PE250 high-throughput sequencing platform. Sequencing data were spliced according to the overlapping relations and filtered to yield effective sequences, and operational taxonomic units (OTUs) was clustered. The diversity index of obtained OUTs was analyzed, and the structure of the bacterial community was analyzed at various taxonomic levels. Results A total of 57 483 valid sequences were obtained using 16S rRNA gene sequencing, and 159 OUTs were classified according to similarity. Then, OUTs at a 97% similarity were included for taxonomic analyses, and the bacteria in Demodex mites belonged to 14 phyla, 20 classes, 51 orders, 72 families, and 94 genera. Proteobacteria was the dominant phylum, and Vibrio, Bradyrhizobium and Variovorax were dominant genera. A total of 56 362 valid sequences were obtained using ITS gene sequencing, and 147 OTUs were obtained, which belonged to 5 phyla, 17 classes, 34 orders, 68 families, and 93 genera and were annotated to Ascomycota, Basidiomycota and Chytridiomycota, with Ascomycota as the dominant phylum, and Alternaria alternata, Epicoccum, Penicillium, and Sarocladium as dominant genera. Conclusions There is a high diversity in the composition of bacterial communities in human Demodex mites, with multiple types of microorganisms and high species abundance.
5.Clinical trial of Morinda officinalis oligosaccharides in the continuation treatment of adults with mild and moderate depression
Shu-Zhe ZHOU ; Zu-Cheng HAN ; Xiu-Zhen WANG ; Yan-Qing CHEN ; Ya-Ling HU ; Xue-Qin YU ; Bin-Hong WANG ; Guo-Zhen FAN ; Hong SANG ; Ying HAI ; Zhi-Jie JIA ; Zhan-Min WANG ; Yan WEI ; Jian-Guo ZHU ; Xue-Qin SONG ; Zhi-Dong LIU ; Li KUANG ; Hong-Ming WANG ; Feng TIAN ; Yu-Xin LI ; Ling ZHANG ; Hai LIN ; Bin WU ; Chao-Ying WANG ; Chang LIU ; Jia-Fan SUN ; Shao-Xiao YAN ; Jun LIU ; Shou-Fu XIE ; Mao-Sheng FANG ; Wei-Feng MI ; Hong-Yan ZHANG
The Chinese Journal of Clinical Pharmacology 2024;40(6):815-819
Objective To observe the efficacy and safety of Morinda officinalis oligosaccharides in the continuation treatment of mild and moderate depression.Methods An open,single-arm,multi-center design was adopted in our study.Adult patients with mild and moderate depression who had received acute treatment of Morinda officinalis oligosaccharides were enrolled and continue to receive Morinda officinalis oligosaccharides capsules for 24 weeks,the dose remained unchanged during continuation treatment.The remission rate,recurrence rate,recurrence time,and the change from baseline to endpoint of Hamilton Depression Scale(HAMD),Hamilton Anxiety Scale(HAMA),Clinical Global Impression-Severity(CGI-S)and Arizona Sexual Experience Scale(ASEX)were evaluated.The incidence of treatment-related adverse events was reported.Results The scores of HAMD-17 at baseline and after treatment were 6.60±1.87 and 5.85±4.18,scores of HAMA were 6.36±3.02 and 4.93±3.09,scores of CGI-S were 1.49±0.56 and 1.29±0.81,scores of ASEX were 15.92±4.72 and 15.57±5.26,with significant difference(P<0.05).After continuation treatment,the remission rate was 54.59%(202 cases/370 cases),and the recurrence rate was 6.49%(24 cases/370 cases),the recurrence time was(64.67±42.47)days.The incidence of treatment-related adverse events was 15.35%(64 cases/417 cases).Conclusion Morinda officinalis oligosaccharides capsules can be effectively used for the continuation treatment of mild and moderate depression,and are well tolerated and safe.
6.A real-world study of clinicopathological characteristics and prognostic factors of gastrointes-tinal stromal tumor with initial surgical resection
Xiaona WANG ; Jingxin CAO ; Baogui WANG ; Hongjie ZHAN ; Yong LIU ; Xuewei DING ; Ning LIU ; Rupeng ZHANG ; Han LIANG
Chinese Journal of Digestive Surgery 2024;23(8):1080-1086
Objective:To investigate the clinicopathological characteristics and prognostic factors of gastrointestinal stromal tumor (GIST) with initial surgical resection.Methods:The retro-spective cohort study was conducted. The clinicopathological data of 847 GIST patients who under-went initial surgical resection in Tianjin Medical University Cancer Institute & Hospital from January 2011 to December 2020 were collected. There were 405 males and 442 females, aged (60±10)years. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was conducted using the t test. Measurement data with skewed distribution were represented as M(range). Count data were described as absolute numbers or percentages, and comparison between groups was conducted using the chi-square test. Comparison of ordinal data was conducted using the nonparameter rank sum test. The Kaplan-Meier method was used to calculate survival rates. Univariate analysis was conducted using the Log-rank test. Multivariate analysis was conducted using the COX regression model. Results:(1) Clinicopatholo-gical characteristics. Of 847 patients, the tumor primary location was stomach in 585 cases, jejunum and ileum in 142 cases, duodenum in 76 cases, colorectum in 10 cases, esophagus in 3 cases, and extra-gastrointestinal in 31 cases. There were 13 cases with liver metastasis and 22 cases with abdominal metastasis. The tumor maximum diameter was (7±5)cm, and the number of nuclear divisions was 4(range, 0-60) cells/50 high-power field or 5 mm 2. According to risk classification of National Institutes of Health (NIH), 31 cases were of extremely low risk, 238 cases were of low risk, 213 cases were of moderate risk, 365 cases were of high risk. There were 839 of 847 patients positive for CD117, 788 cases positive for Dog-1, 710 cases positive for CD34, respectively. There were 272 cases with Ki-67 <5%, 214 cases with Ki-67 of 5%- 9%, 198 cases with Ki-67 ≥10%, 163 cases with missing data. R 0 resection was in 814 cases and non-R 0 resection was in 33 cases. (2) Gene testing and postoperative adjuvant therapy of GIST patients. ① Gene testing. Of 847 patients, 424 underwent genetic testing. The proportion of genetic testing was 1.89%(1/53) in 2011, 9.76%(8/82) in 2012, 8.45%(6/71) in 2013, 15.66%(13/83) in 2014, 50.00%(40/80) in 2015, 55.26%(42/76) in 2016, 73.86%(65/88) in 2017, 68.27%(71/104) in 2018, 80.65%(75/93) in 2019, 88.03%(103/117) in 2020, respectively. Of 424 with genetic testing, 338 cases had KIT mutation, 31 cases had PDGFRA mutation, 55 cases were wild type. ② Adjuvant therapy. Of 847 patients, 253 patients underwent postoperative adjuvant therapy. The proportions of postoperative adjuvant therapy were 8.82%(21/238), 41.78%(89/213), 39.18%(143/365) in patients of low risk, moderate risk, high risk. Of 578 patients with moderate to high risk, the proportion of postoperative adjuvant therapy was 15.15%(5/33) in 2011, 14.71%(10/68)in 2012, 22.45%(11/49) in 2013, 29.09%(16/55) in 2014, 41.38%(24/58) in 2015, 46.15%(24/52) in 2016, 32.81%(21/64)in 2017, 60.00%(45/75) in 2018, 60.42%(29/48) in 2019, 61.84%(47/76) in 2020, respectively. Of 253 patients underwent postoperative adjuvant therapy, 247 cases received imatinib had 6 cases received sunitinib. (3) Comparison of clinicopathological characteristics of GIST with non-gastric origin and gastric origin. Of 847 patients, 262 cases had non-gastric origin and 585 cases had gastric origin. There were significant differences in gender, the number of tumor, tumor maximum diameter, Ki-67 index, risk classification of NIH, and R 0 resection between the two groups ( χ2=8.62, 8.40, 12.97, 6.57, Z=-6.15, χ2=17.19, P<0.05). (4) Analysis of influencing factors for recurrence-free survival rate in GIST patients. Results of multivariate analysis showed that the year of initial diagnosis, primary site, tumor maximum diameter, mitotic image, risk classification of NIH, R 0 resection, genetic testing and postoperative adjuvant therapy were independent factors influencing recurrence-free survival rate in GIST patients with initial surgical resection ( hazard ratio=0.58, 0.61, 2.00, 1.71, 5.81, 2.56, 0.65, 0.38, 95% confidence interval as 0.39-0.85, 0.45-0.83, 1.46-2.74, 1.24-2.35, 3.16-10.69, 1.63-4.02, 0.46-0.94, 0.25-0.56, P<0.05). Conclusions:GIST with initial surgical resection is common located in stomach, with high positive rate in CD117 and Dog-1. The number of people undergoing genetic testing and targeted therapy for GIST is increasing year by year. There are significant differ-ences in clinicopathological characteristics between GIST with non-gastric origin and gastric origin. The year of initial diagnosis, primary site, tumor maximum diameter, mitotic image, risk classifica-tion of NIH, R 0 resection, genetic testing and postoperative adjuvant therapy are independent factors influencing recurrence-free survival rate in GIST patients with initial surgical resection.
7.A multicenter study of neonatal stroke in Shenzhen,China
Li-Xiu SHI ; Jin-Xing FENG ; Yan-Fang WEI ; Xin-Ru LU ; Yu-Xi ZHANG ; Lin-Ying YANG ; Sheng-Nan HE ; Pei-Juan CHEN ; Jing HAN ; Cheng CHEN ; Hui-Ying TU ; Zhang-Bin YU ; Jin-Jie HUANG ; Shu-Juan ZENG ; Wan-Ling CHEN ; Ying LIU ; Yan-Ping GUO ; Jiao-Yu MAO ; Xiao-Dong LI ; Qian-Shen ZHANG ; Zhi-Li XIE ; Mei-Ying HUANG ; Kun-Shan YAN ; Er-Ya YING ; Jun CHEN ; Yan-Rong WANG ; Ya-Ping LIU ; Bo SONG ; Hua-Yan LIU ; Xiao-Dong XIAO ; Hong TANG ; Yu-Na WANG ; Yin-Sha CAI ; Qi LONG ; Han-Qiang XU ; Hui-Zhan WANG ; Qian SUN ; Fang HAN ; Rui-Biao ZHANG ; Chuan-Zhong YANG ; Lei DOU ; Hui-Ju SHI ; Rui WANG ; Ping JIANG ; Shenzhen Neonatal Data Network
Chinese Journal of Contemporary Pediatrics 2024;26(5):450-455
Objective To investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75%(27/36);boys accounted for 64%(23/36).Among the 36 neonates,31(86%)had disease onset within 3 days after birth,and 19(53%)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61%)had left cerebral infarction and 13(36%)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75%)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72%)and seizures in 10 neonates(34%).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33%,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44%(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.
8.Disease spectrum analysis of 1 520 cases with lysosomal storage disorders
Siyu CHANG ; Xiaolan GAO ; Yu WANG ; Ting CHEN ; Xia ZHAN ; Lianshu HAN ; Wenjuan QIU ; Xuefan GU ; Huiwen ZHANG
Chinese Journal of Applied Clinical Pediatrics 2023;38(1):60-63
Objective:To analyze the disease spectrum of lysosomal storage disorders(LSDs) and explore the prevalent distributions of different LSD types in one center in Shanghai.Methods:A retrospective analysis was made.A total of 5 476 suspected LSD patients, including 3 415 males and 2 061 females, with a median age of 4 years(1 day to 72 years), were collected from Xinhua Hospital, Shanghai Jiaotong University School of Medicine from August 2008 to May 2022.The activity of different lysosomal enzymes was detected by fluorescent and biochemical methods.Results:A total of 1 520 patients were diagnosed with LSDs, including 972 males and 548 females, with a median age of 4 years(1 day to 59 years), involving 19 different subtypes.Mucopolysaccharidosis(MPS) was the most common type among LSDs, with a frequency of 45.46%(691/1 520), followed by sphingolipidoses [33.88%(515/1 520)] and glycogen storage disease type Ⅱ [16.05%(244/1 520)] successively.MPS Ⅱ was the most common type in MPS, with a frequency of 45.73%(316/691), followed by MPS ⅣA [22.87%(158/691)]. Niemann-Pick A/B, Gaucher, and Krabbe diseases were common in Sphingolipidoses patients, with frequencies of 37.09%(191/515), 34.37%(177/515), and 10.29%(53/515), respectively.Conclusions:LSDs are common genetic metabolic diseases, especially MPS and sphingolipidoses.Newborn screening for LSDs should be carried out timely so that the patients can be treated early and their prognosis can be improved.
9.Nature-effect transformation mechanism of mulberry leaves and silkworm droppings based on chemical composition analysis.
Ai-Ping DENG ; Yue ZHANG ; Yi-Han WANG ; Jia-Chen ZHAO ; Jin-Xiu QIAN ; Li-Ping KANG ; Tie-Gui NAN ; Zhi-Lai ZHAN
China Journal of Chinese Materia Medica 2023;48(8):2160-2185
Starting with the relationship between mulberry leaves and silkworm droppings as food and metabolites, this study systematically compared the chemical components, screened out differential components, and quantitatively analyzed the main differential components based on ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS) and UPLC-Q-TRAP-MS combined with principal component analysis(PCA) and orthogonal partial least squares-discriminant analysis(OPLS-DA). Moreover, the in vitro enzymatic transformation of the representative differential components was studied. The results showed that(1) 95 components were identified from mulberry leaves and silkworm droppings, among which 27 components only exist in mulberry leaves and 8 components in silkworm droppings. The main differential components were flavonoid glycosides and chlorogenic acids.(2) Nineteen components with significant difference were quantitatively analyzed, and the components with significant differences and high content were neochlorogenic acid, chlorogenic acid, and rutin.(3) The crude protease in the mid-gut of silkworm significantly metabolized neochlorogenic acid and chlorogenic acid, which may be an important reason for the efficacy change in mulberry leaves and silkworm droppings. This study lays a scientific foundation for the development, utilization, and quality control of mulberry leaves and silkworm droppings. It provides references for clarifying the possible material basis and mechanism of the pungent-cool and dispersing nature of mulberry leaves transforming into the pungent-warm and dampness-resolving nature of silkworm droppings, and offers a new idea for the study of nature-effect transformation mechanism of traditional Chinese medicine.
Animals
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Bombyx
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Morus/chemistry*
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Chlorogenic Acid/analysis*
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Gas Chromatography-Mass Spectrometry
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Chromatography, High Pressure Liquid/methods*
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Plant Leaves/chemistry*
10.Effects of three-dimensional bioprinting antibacterial hydrogel on full-thickness skin defect wounds in rats.
Rong Hua JIN ; Zhen Zhen ZHANG ; Peng Qin XU ; Si Zhan XIA ; Ting Ting WENG ; Zhi Kang ZHU ; Xin Gang WANG ; Chuan Gang YOU ; Chun Mao HAN
Chinese Journal of Burns 2023;39(2):165-174
Objective: To explore the effects of three-dimensional (3D) bioprinting gelatin methacrylamide (GelMA) hydrogel loaded with nano silver on full-thickness skin defect wounds in rats. Methods: The experimental research method was adopted. The morphology, particle diameter, and distribution of silver nanoparticles in nano silver solution with different mass concentrations and the pore structure of silver-containing GelMA hydrogel with different final mass fractions of GelMA were observed by scanning electron microscope and the pore size was calculated. On treatment day 1, 3, 7, and 14, the concentration of nano silver released from the hydrogel containing GelMA with final mass fraction of 15% and nano silver with final mass concentration of 10 mg/L was detected by mass spectrometer. At 24 h of culture, the diameters of inhibition zone of GelMA hydrogel containing final mass concentration of 0 (no nano silver), 25, 50, and 100 mg/L nano silver against Staphylococcus aureus and Escherichia coli were detected. Fibroblasts (Fbs) and adipose stem cells (ASCs) were isolated respectively by enzymatic digestion using the discarded prepuce after circumcision from a 5-year-old healthy boy who was treated in the Department of Urology of the Second Affiliated Hospital of Zhejiang University School of Medicine in July 2020, and the discarded fat tissue after liposuction from a 23-year-old healthy woman who was treated in the Department of Plastic Surgery of the Hospital in July 2020. The Fbs were divided into blank control group (culture medium only), 2 mg/L nano sliver group, 5 mg/L nano sliver group, 10 mg/L nano sliver group, 25 mg/L nano sliver group, and 50 mg/L nano sliver group, which were added with the corresponding final mass concentrations of nano sliver solution, respectively. At 48 h of culture, the Fb proliferation viability was detected by cell counting kit 8 method. The Fbs were divided into 0 mg/L silver-containing GelMA hydrogel group, 10 mg/L silver-containing GelMA hydrogel group, 50 mg/L silver-containing GelMA hydrogel group, and 100 mg/L silver-containing GelMA hydrogel group and then were correspondingly treated. On culture day 1, 3, and 7, the Fb proliferation viability was detected as before. The ASCs were mixed into GelMA hydrogel and divided into 3D bioprinting group and non-printing group. On culture day 1, 3, and 7, the ASC proliferation viability was detected as before and cell growth was observed by live/dead cell fluorescence staining. The sample numbers in the above experiments were all 3. Four full-thickness skin defect wounds were produced on the back of 18 male Sprague-Dawley rats aged 4 to 6 weeks. The wounds were divided into hydrogel alone group, hydrogel/nano sliver group, hydrogel scaffold/nano sliver group, and hydrogel scaffold/nano sliver/ASC group, and transplanted with the corresponding scaffolds, respectively. On post injury day (PID) 4, 7, 14, and 21, the wound healing was observed and the wound healing rate was calculated (n=6). On PID 7 and 14, histopathological changes of wounds were observed by hematoxylin eosin staining (n=6). On PID 21, collagen deposition of wounds was observed by Masson staining (n=3). Data were statistically analyzed with one-way analysis of variance, analysis of variance for repeated measurement, Bonferroni correction, and independent sample t test. Results: The sliver nano particles in nano silver solution with different mass concentrations were all round, in scattered distribution and uniform in size. The silver-containing GelMA hydrogels with different final mass fractions of GelMA all showed pore structures of different sizes and interconnections. The pore size of silver-containing GelMA hydrogel with 10% final mass fraction was significantly larger than that of silver-containing GelMA hydrogels with 15% and 20% final mass fractions (with P values both below 0.05). On treatment day 1, 3, and 7, the concentration of nano silver released from silver-containing GelMA hydrogel in vitro showed a relatively flat trend. On treatment day 14, the concentration of released nano silver in vitro increased rapidly. At 24 h of culture, the diameters of inhibition zone of GelMA hydrogel containing 0, 25, 50, and 100 mg/L nano silver against Staphylococcus aureus and Escherichia coli were 0, 0, 0.7, and 2.1 mm and 0, 1.4, 3.2, and 3.3 mm, respectively. At 48 h of culture, the proliferation activity of Fbs in 2 mg/L nano silver group and 5 mg/L nano silver group was both significantly higher than that in blank control group (P<0.05), and the proliferation activity of Fbs in 10 mg/L nano silver group, 25 mg/L nano silver group, and 50 mg/L nano silver group was all significantly lower than that in blank control group (P<0.05). Compared with the that of Fbs in 0 mg/L silver-containing GelMA hydrogel group, the proliferation activity of Fbs in 50 mg/L silver-containing GelMA hydrogel group and 100 mg/L silver-containing GelMA hydrogel group was all significantly decreased on culture day 1 (P<0.05); the proliferation activity of Fbs in 50 mg/L silver-containing GelMA hydrogel group was significantly increased (P<0.05), while the proliferation activity of Fbs in 100 mg/L silver-containing GelMA hydrogel group was significantly decreased on culture day 3 (P<0.05); the proliferation activity of Fbs in 100 mg/L silver-containing GelMA hydrogel group was significantly decreased on culture day 7 (P<0.05). The proliferation activity of ASCs in 3D bioprinting group show no statistically significant differences to that in non-printing group on culture day 1 (P>0.05). The proliferation activity of ASCs in 3D bioprinting group was significantly higher than that in non-printing group on culture day 3 and 7 (with t values of 21.50 and 12.95, respectively, P<0.05). On culture day 1, the number of dead ASCs in 3D bioprinting group was slightly more than that in non-printing group. On culture day 3 and 5, the majority of ASCs in 3D bioprinting group and non-printing group were living cells. On PID 4, the wounds of rats in hydrogel alone group and hydrogel/nano sliver group had more exudation, and the wounds of rats in hydrogel scaffold/nano sliver group and hydrogel scaffold/nano sliver/ASC group were dry without obvious signs of infection. On PID 7, there was still a small amount of exudation on the wounds of rats in hydrogel alone group and hydrogel/nano sliver group, while the wounds of rats in hydrogel scaffold/nano sliver group and hydrogel scaffold/nano sliver/ASC group were dry and scabbed. On PID 14, the hydrogels on the wound surface of rats in the four groups all fell off. On PID 21, a small area of wounds remained unhealed in hydrogel alone group. On PID 4 and 7, the wound healing rates of rats in hydrogel scaffold/nano sliver/ASC group were significantly higher than those of the other three groups (P<0.05). On PID 14, the wound healing rate of rats in hydrogel scaffold/nano sliver/ASC group was significantly higher than the wound healing rates in hydrogel alone group and hydrogel/nano sliver group (all P<0.05). On PID 21, the wound healing rate of rats in hydrogel alone group was significantly lower than that in hydrogel scaffold/nano sliver/ASC group (P<0.05). On PID 7, the hydrogels on the wound surface of rats in the four groups remained in place; on PID 14, the hydrogel in hydrogel alone group was separated from the wounds of rats, while some hydrogels still existed in the new tissue of the wounds of rats in the other three groups. On PID 21, the collagen arrangement in the wounds of rats in hydrogel alone group was out of order, while the collagen arrangement in the wounds of rats in hydrogel/nano sliver group, and hydrogel scaffold/nano sliver/ASC group was relatively orderly. Conclusions: Silver-containing GelMA hydrogel has good biocompatibility and antibacterial properties. Its three-dimensional bioprinted double-layer structure can better integrate with new formed tissue in the full-thickness skin defect wounds in rats and promote wound healing.
Male
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Rats
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Animals
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Humans
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Hydrogels/pharmacology*
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Bioprinting
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Metal Nanoparticles
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Rats, Sprague-Dawley
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Silver/pharmacology*
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Soft Tissue Injuries
;
Anti-Bacterial Agents

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