Objective To investigate the establishment and evaluation of an idiopathic pulmonary fibrosis(IPF)mouse model induced by the intratracheal infusion of bleomycin(BLM)of different concentrations.Methods Male C57BL/6J mice were randomly divided into a control group,Model-L group(1.5 mg/kg,BLM),Model-M group(2.5 mg/kg,BLM),and Model-H group(3.5 mg/kg,BLM).An IPF mouse model was constructed by one-time intratracheal infusion of BLM.The general status,body mass,survival rate,and lung coefficient of mice in different groups were compared.Pathological changes in lung tissue,the hydroxyproline content,fibrosis markers and inflammatory factor levels were observed.Results Compared with the control group,the survival rate decreased and body weight showed a downward trend in the low-,medium-,and high-dose model groups,with significant increases in lung coefficients.Inflammatory infiltration(P＜0.01)and collagen deposition(P＜0.0001)were observed in the lung tissues of all model groups.Hydroxyproline levels in lung tissue and serum were significantly elevated(P＜0.05).The mRNA levels of fibrosis markers α-Sma,Fn1,and Col1a1 were upregulated(P＜0.001),with significant increases in corresponding protein expression(P＜0.05).The mRNA expression of the inflammatory factor Tgfb1 also increased(P＜0.0001).Conclusion 1.5,2.5 and 3.5 mg/kg BLM can induce an IPF model in C57BL/6J mice.Based on the results observed for survival rate,body mass,lung coefficient changes,lung tissue gross and pathological changes,and fibrosis-related biomarkers,2.5 mg/kg BLM is the optimal concentration for inducing an IPF mouse model.

Animal experiments are crucial in evaluating the preclinical safety and efficacy of new dental materials, drugs, instruments, and equipment by identifying and eliminating potential health risks to humans. An international team of several dental experts formulated a guideline named Preferred Reporting Items for Animal Studiesin Endodontology (PRIASE) 2021. Consisting of 11 domains, 43 individual items, and a flowchart. PRIASE provides guidance for animal experiments in dentistry and improves the quality of experiment design and reporting. This work introduces the process and basic content of the guideline and interprets the key items of its checklist with specific examples to provide reference for the reporting of animal experiment in dentistry in China.
Animals ; Animal Experimentation/standards* ; Checklist ; China ; Endodontics ; Guidelines as Topic ; Research Design

Objective To investigate the establishment and evaluation of an idiopathic pulmonary fibrosis(IPF)mouse model induced by the intratracheal infusion of bleomycin(BLM)of different concentrations.Methods Male C57BL/6J mice were randomly divided into a control group,Model-L group(1.5 mg/kg,BLM),Model-M group(2.5 mg/kg,BLM),and Model-H group(3.5 mg/kg,BLM).An IPF mouse model was constructed by one-time intratracheal infusion of BLM.The general status,body mass,survival rate,and lung coefficient of mice in different groups were compared.Pathological changes in lung tissue,the hydroxyproline content,fibrosis markers and inflammatory factor levels were observed.Results Compared with the control group,the survival rate decreased and body weight showed a downward trend in the low-,medium-,and high-dose model groups,with significant increases in lung coefficients.Inflammatory infiltration(P＜0.01)and collagen deposition(P＜0.0001)were observed in the lung tissues of all model groups.Hydroxyproline levels in lung tissue and serum were significantly elevated(P＜0.05).The mRNA levels of fibrosis markers α-Sma,Fn1,and Col1a1 were upregulated(P＜0.001),with significant increases in corresponding protein expression(P＜0.05).The mRNA expression of the inflammatory factor Tgfb1 also increased(P＜0.0001).Conclusion 1.5,2.5 and 3.5 mg/kg BLM can induce an IPF model in C57BL/6J mice.Based on the results observed for survival rate,body mass,lung coefficient changes,lung tissue gross and pathological changes,and fibrosis-related biomarkers,2.5 mg/kg BLM is the optimal concentration for inducing an IPF mouse model.

Objective To investigate the impact of exosomal(Exos)-miR-21-5p(miR-21)targeting S-phase kinase associated protein 2(SKP2)derived from Type Ⅱ alveolar epithelial cells(AEC-Ⅱ)on the patho-genesis of bronchopulmonary dysplasia(BPD).Methods A total of 60 SD rats aged 6～8 weeks were utilized in this study,with 30 of them subjected to extraction and culture through differential adherent centrifugation.Density gradient centrifugation was employed for the isolation of AEC-Ⅱ derived exosomes,while vesicles from AEC-Ⅱ me-dium were extracted using density gradient centrifugation.These isolates were subsequently confirmed by transmission electron microscopy and particle size analysis,and the targeting relationship between miR-21 and SKP2 was validated through dual-fluorescein reporter gene assay.The remaining 30 mice were combined in a male-to-female ratio of 3:1 to facilitate pregnancy testing.These neonatal mice were randomly assigned into four experimental groups:air control group(Con group),hyperoxia group(BPD+PBS group),hyperoxia-treated mice receiving exosomes(BPD+Exos-miR-21 group),and hyperoxia combined with exosome miR-21 inhibitor treatment group(BPD+Exos-AV-miR-21 group).Neonatal SD rats will be exposed to 85％oxygen to establish a BPD model.Follow-ing 14 days of high oxygen treatment,the expression levels of miR-21 in lung tissues and exosomes will be assessed using RT-qPCR.HE staining will be employed to observe pathological changes in lung tissue,while mean alveolar linear intercept(MLI)and radial alveolar count(RAC)will be calculated.Superoxide dismutase(SOD),malondialdehyde(MDA),and total antioxidant capacity(T-AOC)levels will be determined spectrophoto-metrically,whereas reactive oxygen species(ROS)levels will be measured via fluorescence spectrophotometry.Additionally,Western blot analysis will assess the expression levels of SKP2,NR2F2,and VEGF-A proteins.Results The results obtained from electron microscopy and particle size analysis demonstrated that the vesicle structure isolated from AEC-Ⅱ cells corresponded to exosomes.Moreover,there was a significant upregulation of miR-21 expression in exosomes(P＜0.01).Subsequently,the dual luciferase gene reporter assay con-firmed SKP2 as the target of miR-21.Comparative analysis revealed that compared to the Con group,both BPD+PBS and BPD+Exos-AV-miR-21 groups exhibited disordered lung tissue structure with enlarged and simpli-fied alveoli,increased levels of ROS,MDA,and MLI along with elevated expression of SKP2 protein(P＜0.01).Conversely,RAC,SOD,T-AOC levels were downregulated alongside miR-21 expression while NR2F2 and VEGF-A protein expressions decreased significantly(P＜0.01).In contrast to the BPD+PBS group,the number of alveoli without alveoli increased in the BPD+Exos-miR-21 group leading to improved degree of alveolar simplification accom-panied by reduced MLI,ROS,MDA levels as well as decreased SKP2 protein expression(P＜0.01).Addition-ally ROC,SOD,T-AOC,and miR-21 expressions were upregulated while NR2F2and VEGF-A expressions were increased(P＜0.01).Conclusions The exosomal miR-21 derived from AEC-Ⅱ may potentially target SKP2,thereby inhibiting oxidative stress and promoting alveolar development.Consequently,it can improve BPD by enhancing the protein expression of NR2F2 and VEGF-A.

Objective:To explore the function of MDM2 and its relationship with p53 at the cellular level during H 2O 2 induced oxidative damage. Methods:MLE-12 HALI cell models were established using 0.5 mmol/L H 2O 2, and were divided into three groups: normal control group, H 2O 2 injury group, H 2O 2+MDM2 overexpressed group, and H 2O 2+MDM2 shRNA group. Infection of MLE-12 cells with adenovirus vector overexpressing and silencing MDM2; Using immunoprecipitation (Co-IP) to analyze the interaction between MDM2 and p53; Western blotting was used to detect the protein expression levels of MDM2, p53, Bcl-2, Bax, and cleared caspase-3 after HALI modeling; Measure the apoptosis rate of cells in each group. Results:After transcriptome sequencing,the p53 signaling pathway closely related to HALI. Compared with the normal group, the expression of MDM2 in the H 2O 2 injury group was lower ( P<0.05); Compared with the H 2O 2 injury group, overexpression of MDM2 resulted in a decrease in the apoptosis rate of MLE-12 cells ( P<0.05), a decrease in the expression levels of p53, Bax, and cleared caspase-3 proteins, and an upregulation of MDM2 and Bcl-2 protein expression ( P<0.05). Compared with the H 2O 2 injury group, when MDM2 was silenced, the cell apoptosis rate increased ( P<0.05), and the expression levels of p53, Bax, and cleared caspase-3 proteins were upregulated, while the expression levels of MDM2 and Bcl-2 proteins decreased ( P<0.05). Co-IP experiments showed that MDM2 binds to p53 protein. Conclusions:MDM2 can exert a protective effect on HALI by inhibiting MLE-12 cell apoptosis through the p53/Bcl-2/Bax axis.

The healthcare aid to foreign countries undertaken by China is a challenging and honorable task.Healthcare aid team members often face numerous issues that can impact their physical and mental health.These factors may stem from their deployment in economically and socially marginalized regions characterized by poor healthcare infrastructure,diverse cultural and linguistic barriers,bringing challenges to both their work and mental health.Several elements such as substandard living condi-tions,cultural disparities,occupational stress,and homesickness can have a significantly detrimental effect on the physical and mental health of these medical aid personnel.By utilizing the case study of the sixth Chinese medical team deployed in Dominica,we aimed to thoughtfully consider and identify specific strategies to safeguard the physical and mental health of healthcare aid per-sonnel.By addressing these pivotal issues,we aspired to offer valuable insights and practical guidance for future healthcare aid personnel,hoping our reflections can facilitate more effective execution of their duties.

Objective To investigate the impact of exosomal(Exos)-miR-21-5p(miR-21)targeting S-phase kinase associated protein 2(SKP2)derived from Type Ⅱ alveolar epithelial cells(AEC-Ⅱ)on the patho-genesis of bronchopulmonary dysplasia(BPD).Methods A total of 60 SD rats aged 6～8 weeks were utilized in this study,with 30 of them subjected to extraction and culture through differential adherent centrifugation.Density gradient centrifugation was employed for the isolation of AEC-Ⅱ derived exosomes,while vesicles from AEC-Ⅱ me-dium were extracted using density gradient centrifugation.These isolates were subsequently confirmed by transmission electron microscopy and particle size analysis,and the targeting relationship between miR-21 and SKP2 was validated through dual-fluorescein reporter gene assay.The remaining 30 mice were combined in a male-to-female ratio of 3:1 to facilitate pregnancy testing.These neonatal mice were randomly assigned into four experimental groups:air control group(Con group),hyperoxia group(BPD+PBS group),hyperoxia-treated mice receiving exosomes(BPD+Exos-miR-21 group),and hyperoxia combined with exosome miR-21 inhibitor treatment group(BPD+Exos-AV-miR-21 group).Neonatal SD rats will be exposed to 85％oxygen to establish a BPD model.Follow-ing 14 days of high oxygen treatment,the expression levels of miR-21 in lung tissues and exosomes will be assessed using RT-qPCR.HE staining will be employed to observe pathological changes in lung tissue,while mean alveolar linear intercept(MLI)and radial alveolar count(RAC)will be calculated.Superoxide dismutase(SOD),malondialdehyde(MDA),and total antioxidant capacity(T-AOC)levels will be determined spectrophoto-metrically,whereas reactive oxygen species(ROS)levels will be measured via fluorescence spectrophotometry.Additionally,Western blot analysis will assess the expression levels of SKP2,NR2F2,and VEGF-A proteins.Results The results obtained from electron microscopy and particle size analysis demonstrated that the vesicle structure isolated from AEC-Ⅱ cells corresponded to exosomes.Moreover,there was a significant upregulation of miR-21 expression in exosomes(P＜0.01).Subsequently,the dual luciferase gene reporter assay con-firmed SKP2 as the target of miR-21.Comparative analysis revealed that compared to the Con group,both BPD+PBS and BPD+Exos-AV-miR-21 groups exhibited disordered lung tissue structure with enlarged and simpli-fied alveoli,increased levels of ROS,MDA,and MLI along with elevated expression of SKP2 protein(P＜0.01).Conversely,RAC,SOD,T-AOC levels were downregulated alongside miR-21 expression while NR2F2 and VEGF-A protein expressions decreased significantly(P＜0.01).In contrast to the BPD+PBS group,the number of alveoli without alveoli increased in the BPD+Exos-miR-21 group leading to improved degree of alveolar simplification accom-panied by reduced MLI,ROS,MDA levels as well as decreased SKP2 protein expression(P＜0.01).Addition-ally ROC,SOD,T-AOC,and miR-21 expressions were upregulated while NR2F2and VEGF-A expressions were increased(P＜0.01).Conclusions The exosomal miR-21 derived from AEC-Ⅱ may potentially target SKP2,thereby inhibiting oxidative stress and promoting alveolar development.Consequently,it can improve BPD by enhancing the protein expression of NR2F2 and VEGF-A.

Humans ; COVID-19/genetics* ; SARS-CoV-2/genetics* ; Clustered Regularly Interspaced Short Palindromic Repeats/genetics* ; CRISPR-Cas Systems/genetics* ; RNA, Viral/genetics*

Objective:To develop the Sexual Health Education Needs Assessment Scale for Breast Cancer Patients and test its reliability and validity.Methods:Guided by Maslow's hierarchy of needs theory and knowledge, belief, and practice theory, an initial scale was formed through literature review, semi-structured interviews and Delphi expert consultation. Through cognitive interviews with 9 patients, the scale was further revised and improved to form a clinical trial version. From December 2021 to September 2022, 397 breast cancer patients from 9 ClassⅢ hospitals in 6 provinces, municipalities and autonomous regions were selected by convenience sampling to conduct a questionnaire survey, test the reliability and validity of the scale and grade it.Results:The Sexual Health Education Needs Assessment Scale for Breast Cancer Patients included four dimensions and 32 items in total. Exploratory factor analysis extracted a total of four common factors, with a cumulative variance contribution rate of 72.258%. The content validity index of the scale was 0.865, and the content validity index of each item was 0.929 to 1.000. The correlation coefficients between each dimension of the scale and the total scale were 0.789 to 0.956, and the correlation coefficients between dimensions were 0.635 to 0.863. The Cronbach's α coefficient of the total scale was 0.979, and the Cronbach's α coefficients of each dimension were 0.897 to 0.969. The half reliability of the total scale was 0.941, and the half reliability of each dimension was 0.851 to 0.946. The total score of the scale was 32 to 160, with 32 to 77 being at a low level, 78 to 117 being at a medium level, and 118 to 160 being at a high level.Conclusions:The developed Sexual Health Education Needs Assessment Scale for Breast Cancer Patients has good reliability and validity, and is suitable for breast cancer patients' sexual health education needs assessment.

Objective:To analyze the potential risk factors of periventricular-intraventricular hemorrhage(PIVH)in premature infants.Methods:A retrospective study was conducted on clinical data of 279 premature infants admitted to the Affiliated Hospital of Guizhou Medical University From January 1, 2019 to December 31, 2019, who completed cranial ultrasound during hospitalization.According to the cranial ultrasound with or without PIVH, the cases were divided into PIVH group and non-PIVH group.The premature infants with PIVH were divided into severe PIVH(grade Ⅲ and Ⅳ)group and mild PIVH(grade Ⅰand Ⅱ)group according to the PIVH grades.A total of 25 factors, which may influnce PIVH, were analyzed by univariate analysis, and then multivariate Logistic stepwise regression analysis(stepwise backwards method)was performed to determine the major risk factors.Results:(1)A total of 279 premature infants were included in the study, 133 of them in PIVH group, and 146 of them in non-PIVH group.Univariate analysis showed that there were statistically significant differences in 14 factors between two groups, including full treatment of antenatal steroid, gestation age, birth weight, neonatal asphyxia, hypothermia, early onset sepsis, metabolic acidosis, hypernatremia, anemia, respiratory distress syndrome, noninvasive ventilation, invasive ventilation, invasive ventilation within 72 hours after birth, and lumbar puncture within 72 hours after birth( P<0.05). Multivariate analysis showed that gestational age( OR=0.709, 95% CI 0.602-0.835), and full treatment of antenatal steroid( OR=0.354, 95% CI 0.189-0.664) were protective factors for PIVH in premature infants, while neonatal asphyxia( OR=2.425, 95% CI 1.171-5.023), hypothermia( OR=2.097, 95% CI 1.088~4.041), early onset sepsis( OR=12.898, 95% CI 1.433-115.264), metabolic acidosis( OR=2.493, 95% CI 1.398-4.442), invasive ventilation within 72 hours after birth( OR=5.408, 95% CI 1.156-25.297), lumbar puncture within 72 hours after birth ( OR=5.035, 95% CI 1.269-19.993) were independent risk factors for PIVH in premature infants( P<0.05). (2) Among 133 cases of premature PIVH, 20 cases were severe PIVH and 13 cases were mild PIVH.Univariate analysis showed that there were statistically significant differences in 5 factors between two groups, including antenatal magnesium sulfate, gestation age, early onset sepsis, abnormal coagulation, and lumbar puncture within 72 hours after birth.Multivariate analysis showed that early onset sepsis( OR=4.392, 95% CI 1.343-14.367) and abnormal coagulation( OR=3.502, 95% CI 1.234-9.867) were independent risk factors for severe PIVH in premature infants( P<0.05). Conclusion:Gestational age is negatively correlated with the occurrence of PIVH in premature infants, and completion of more than a course of treatment for antenatal dexamethasone is an independent protective factor of PIVH in premature infants.Neonatal asphyxia, metabolic acidosis, hypothermia(<35 ℃), early onset sepsis, invasive ventilation within 72 hours after birth, and lumbar puncture within 72 hours after birth are independent risk factors for PIVH in premature infants.Abnormal coagulation and early onset sepsis are independent risk factors for severe PIVH in premature infants.