BACKGROUND:In recent years,numerous studies have shown that autophagy and mitophagy play an important role in the regulation of bone metabolism.Under non-physiological conditions,mitophagy breaks the balance of bone metabolism and triggers metabolism disorders,which affect osteoblasts,osteoclasts,osteocytes,chondrocytes,bone marrow mesenchymal stem cells,etc. OBJECTIVE:To summarize the mechanism of mitophagy in regulating bone metabolic diseases and its application in clinical treatment. METHODS:PubMed,Web of Science,CNKI,WanFang and VIP databases were searched by computer using the keywords of"mitophagy,bone metabolism,osteoblasts,osteoclasts,osteocytes,chondrocytes,bone marrow mesenchymal stem cells"in English and Chinese.The search time was from 2008 to 2023.According to the inclusion criteria,90 articles were finally included for review and analysis. RESULTS AND CONCLUSION:Mitophagy promotes the generation of osteoblasts through SIRT1,PINK1/Parkin,FOXO3 and PI3K signaling pathways,while inhibiting osteoclast function through PINK1/Parkin and SIRT1 signaling pathways.Mitophagy leads to bone loss by increasing calcium phosphate particles and tissue protein kinase K in bone tissue.Mitophagy improves the function of chondrocytes through PINK1/Parkin,PI3K/AKT/mTOR and AMPK signaling pathways.Modulation of mitophagy shows great potential in the treatment of bone diseases,but there are still some issues to be further explored,such as different stages of drug-activated mitophagy,and the regulatory mechanisms of different signaling pathways.

Background As one of the key populations in the prevention and treatment of iodine deficiency disorders, it is important to continuously monitor the iodine nutritional level of school-age children. The current reference interval for thyroid volume in China is based on age only, without taking into account differences in individual developmental levels, and the distribution of thyroid volume may vary regionally due to economic, demographic, and environmental factors. The current reference cut-off points for thyroid volume proposed by the World Health Organization are not based on the Chinese population. Objective To understand the iodine nutritional status and distribution of thyroid volume (Tvol) among children aged 8-10 years in Huangpu District, Shanghai, China, to identify impact factors of Tvol, and to propose a reference range upper limit for local thyroid health surveillance, so as to provide a basis for goiter control and prevention. Methods Six hundred children aged 8-10 years in Huangpu District were recruited in 2017, 2020, and 2023, and body height, weight, thyroid volume, urinary iodine, and iodine content of household edible salt were determined. A multilevel model was constructed using population density and area as regional variables, and age, body surface area (BSA), and body mass index (BMI) as potential impact factors for at the individual level, to assess their effects on thyroid volume. Quantile regression of thyroid volume was performed, and the 98th percentile (P₉₈) of thyroid volume was predicted based on age and BSA. Results The iodized salt coverage in the households of surveyed children in 2017, 2020, and 2023 was 72.0%, 57.0%, and 48.0%, respectively, and the iodized salt coverage decreased by year (χ²=24.31, P<0.001). The urinary iodine level of children in 2017 was higher than that in 2020 and 2023 (χ²=18.77, P<0.001). The Tvol medians of children in 2017, 2020, and 2023 were 2.29, 2.49, and 2.97 mL, respectively, and the Tvol increased by year (χ²=60.04, P<0.001). The proportion of goiter was higher in children in 2023 than in 2017 and 2020 (χ²=6.57, P<0.05). Sex differences were not statistically significant for urinary iodine levels, thyroid volume, and goiter. The median Tvol was 2.26, 2.58, and 2.76 mL in children of 8, 9, and 10 years old respectively, and the Tvol increased with age (χ²=49.02, P <0.001). Tvol was positively correlated with age, BSA, and BMI with correlation coefficients of 0.2846, 0.3723, and 0.2950, respectively. The final quantile regression model showed that the strongest effect of BSA was associated with the 98th percentile of Tvol. Multilevel models considering population density or area as regional variables failed to achieve convergence. Conclusion To establish the upper limit of the reference interval for thyroid volume of healthy children in Huangpu District, the effects of age and BSA should be considered at the individual level, and the upper limit of the normal interval for goiter screening is suggested to be the 98th percentile value of BSA at the same age. In addition, the adaptability of population density and regional area as indicators of regional aggregation of thyroid volume distribution still needs to be further explored.

Objective To investigate the role of cytochrome P450 2E1 (CYP2E1) in trichloroethylene (TCE)-induced skin sensitization and liver damage in guinea pigs, using diallyl sulfide (DAS), a CYP2E1 inhibitor, as an intervention. Methods Specific pathogen-free female guinea pigs were randomly divided into blank control group, solvent control group, positive control (2,4-dinitrochlorobenzene) group, TCE-exposure group, and DAS-intervention group. Skin sensitization experiments were conducted using the guinea pig TCE maximal dose-skin sensitization test. Urinary trichloroacetic acid levels were determined following TCE induction and challenge. At 48 hours after the final challenge, serum liver function markers and inflammatory cytokines levels were detected. Histopathological examination on skin and liver tissues was performed, and hepatic CYP2E1 protein expression and oxidative stress indicators were assessed. Results The sensitization rates of guinea pigs were 100.0%, 75.0%, and 33.3% in the positive control, TCE-exposure, and DAS-intervention groups, respectively, while the blank control and solvent control groups were both 0.0%. Compared with the guinea pigs in TCE-exposure group, those in the DAS-intervention group had lower urinary trichloroacetic acid levels at intradermal induction, local induction, first challenge, and 24 hours after the final challenge time point (all P<0.05). Histopathology of guinea pigs showed dermal inflammatory infiltration and basal keratinocyte necrosis in the TCE-exposure group, whereas only mild dermal inflammation was observed in the DAS-intervention group. The guinea pigs in TCE-exposure group exhibited diffuse hepatocellular necrosis, while hepatic damage in the DAS-intervention group was alleviated, characterized by only mild hepatocellular steatosis and hepatocyte swelling around the central vein. The skin sensitization rate of guinea pigs in the TCE-exposure group increased (all P<0.01), the serum alanine aminotransferase (ALT )activity, the levels of interleukin (IL)-2, IL-17, and tumor necrosis factor-α (TNF- α) increased (all P<0.05), the relative expression of CYP2E1 protein, the activity of superoxide dismutase (SOD), and the level of malondialdehyde in liver tissue increased (all P<0.05), while the activity of catalase decreased (P<0.05), compared with the blank control and solvent control groups. The serum ALT activity and the levels of IL-2, IL-17, and TNF-α of guinea pigs in DAS-intervention group reduced (all P<0.05), as well as CYP2E1 protein expression, SOD activity, and malondialdehyde level in liver tissue reduced (all P<0.05), compared with the TCE-exposure group. Conclusion TCE can induce hepatic CYP2E1 expression, thereby promoting oxidative stress and inflammatory responses, which contributes to skin sensitization and liver damage. DAS alleviates TCE-induced toxic effects on skin and liver by inhibiting CYP2E1 expression.

Mytilus is one of bivalves with great economic and ecological values.The innate immune de-fense of Mytilus shows great significance in the study of marine biological immunology.Hemolymph is the main immune tissue for Mytilus.The Nanopore full-length transcriptome of Mytilus coruscus hemocytes,and the serum differential proteomics based on SDS-PAGE analysis were performed to identify key pro-teins involving in the immune response of Mytilus hemolymph in response of different bacteria and fungi stresses.A total of 44 proteins were identified in the serum induced by different microorganisms.Among them,26 proteins showed significant differential expression level in response to different microbial stres-ses,and their functions were involved in protein folding protection,cell autophagy and apoptosis regula-tion,reactive oxygen species production,energy metabolism regulation,cell detoxification,and immune regulation.The changes in expression levels of these proteins varied in response to different bacterial and fungal stresses,suggesting that Mytilus has different immune response strategies to different bacterial and fungal stresses.The results provide a new scientific basis for understanding the differential immune mech-anism of Mytilus innate immune system in response to different types of microbial invasion,as well as the screening of specific biomarker proteins for microbial infection,and provide ideas for the healthy develop-ment and disease prevention of shellfish aquaculture.

Objective:To retrospectively analyze the causes of missed diagnosis of clinically significant PCa(csPCa)by targe-ted biopsy(TB).Methods:This retrospective study included 652 males aged(71.32±16.53)years with elevated PSA and ab-normal MRI signals detected in our hospital from June 2018 to December 2020.We further examined the patients by transperineal pros-tatic TB and systematic biopsy(SB),analyzed the detection rates of PCa and csPCa by TB and SB,and investigated the causes of missed diagnosis of csPCa in TB using the fishbone diagram.Results:The total detection rate of PCa and csPCa by TB combined with SB was 45.7%(298/652),and that of csPCa was 37.4%(244/652),with 38 cases of csPCa missed in TB,including 23 cases of negative TB and 15 cases of low ISUP grade.The causes of missed diagnosis of csPCa by TB included low MRI image quality,PSA density≤0.15 ng/ml/cm3,target area<10 mm,and PI-RADS 2 score≤3.The detection rate of csPCa by TB alone was 31.6%,which was increased by 5.8%(P=0.027)when TB combined with SB.Conclusion:TB combined with SB yields a higher de-tection rate of csPCa than either used alone.Missed diagnosis of csPCa by TB is closely related to the characteristics of tumor and MR image of the target area.

Objective:To explore the short-term efficacy on 3D printing assisted reconstruction of traumatic digit joint defects using rib and costo-osteochondral autograft.Methods:From August 2022 to July 2023, 7 patients with open digit joint defects had undergone emergency primary debridement and fracture fixation in the Department of Orthopaedics, 988th Hospital of the Joint Logistics Support Force of PLA. Patients with more phalangeal defects that could not be aligned were treated with antibiotic bone cement filling in the emergency surgery. In the second stage surgery, bone cement was removed and transfer of rib cartilage graft was performed to reconstruct the digit joint defect. According to a 1∶1 3D printed hand templates, rib cartilage grafts were crafted to the shape of digit joints, and then spliced together the digit joints and bone defects for fixation. Follow-up X-ray examinations were taken and assessment of the healing status of rib and fractures of phalangeal and metacarpophalangeal bones were carried out according to the Paley fracture healing score. At the outpatient follow-up, assessment of transferred joint movement and evaluation of upper limb function were conducted according to the Evaluation Trial Standards of Upper Limb Partial Functional of Hand Surgery of Chinese Medical Association. Visual Analogue Scale (VAS) pain scores were evaluated from the affected digits and donor sites.Results:After reconstructive surgery, all 7 patients had primary healing of the wounds of hand. One patient had fat liquefaction at the donor site, and the rest had primary donor site healing. One patient received further surgery for extensor tendon repair after rib cartilage grafting due to the digital extensor tendon injury. All 7 patients were included in postoperative follow-up for 6-11 months, with an average of 9 months. All patients had excellent fracture healing according to the Paley fracture healing score. At the final follow-up, the extension and flexion of the digit joints were found at 40°-80° (average 56.2°) for proximal interphalangeal joints (4 patients), and 10° in extension and 85° in flexion for metacarpophalangeal joint (1 patient). The range of motion of the thumb interphalangeal joint (2 patients) was 20°-35° (average 27.5°). Hand function was assessed according to Evaluation Trial Standards of Upper Limb Partial Functional of Hand Surgery of Chinese Medical Association and it was found that 3 patients were in excellent, 3 in good and 1 in fair.Conclusion:This study focused on the treatment of traumatic digit joint defects by transfer of individually crafted rib cartilages in reconstruction of the defected digit joint. It significantly improves the appearance and function of the defected digit joints, especially suitable for the irregular defects of phalangeal bones.

Objective To explore the application value of T2*mapping sequence combined with texture feature indicatoror in the diagnosis of postmenopausal osteoporosis(PMOP)in women.Methods The clinical data of 50 PMOP patients admitted to some hospital from March 2019 to April 2021(enrolled into an osteoporosis group)were analyzed retrospectively,and another two groups were established including a normal bone mineral density(BMD)group composed of 50 postmenopausal physical examiners with normal BMD(BMD＞120 mg/cm3)and a reduced BMD group consisting of 50 postmenopausal women with decreased BMD(80 mg/cm3＜BMD＜120 mg/cm3).All the 3 groups underwent magnetic resonance lumbar spine conventional sequence and T2(mapping scanning and image texture feature extraction,which were compared in terms of lumbar T2*value and texture feature indicators including energy,contrast,correlation,deficit distance and entropy.Spearman correlation analysis was used to analyze the correlation between lumbar spine T2*values,texture feature indicators and the occurrence of POMP in women,independent predictors of the occurrence of PMOP in women were determined by multifactorial logistic regression analysis,the diagnostic efficacy of T2*mapping sequence combined with texture feature indicatoror for PMOP was analyzed using ROC curves,and a column-line diagram prediction model for POMP occurrence was constructed and validated.Results There were significant differences in T2*value,energy,contrast,correlation,deficit distance and entropy among the groups(P＜0.05).Spearman correlation analysis showed that with the occurrence of POMP lumbar spine T2*value,contrast and entropy were significantly positively correlated,while energy,correlation and deficit distance were significantly negatively correlated(P＜0.05).T2*value,energy,contrast,correlation,deficit distance and entropy were all independent predictors of the occurrence of POMP(P＜0.05).T2*mapping sequence combined with texture feature indicatoror behaved better than any single indicator in AUC,sensitivity and specificity.The column-line diagram prediction model predicted a 75.00％probability of POMP in women,which was validated with advantages ind1iscrimination,calibration and net benefit rate.Conclusion Magnetic resonance T2*mapping sequence combined with texture feature indicator behaves well in diagnosing POMP of women,and T2*value,energy,contrast,correlation,deficit distance and entropy can be used as sensitive indicators for clinical screening of people at high risk for POMP.[Chinese Medical Equipment Journal,2024,45(8):68-72]

Further evidence is needed to explore the impact of high-altitude environments on the neurologic function of neonates.Non-invasive techniques such as cerebral near-infrared spectroscopy and amplitude-integrated electroencephalography can provide data on cerebral oxygenation and brain electrical activity.This study will conduct multiple cerebral near-infrared spectroscopy and amplitude-integrated electroencephalography monitoring sessions at various time points within the first 3 days postpartum for healthy full-term neonates at different altitudes.The obtained data on cerebral oxygenation and brain electrical activity will be compared between different altitudes,and corresponding reference ranges will be established.The study involves 6 participating centers in the Chinese High Altitude Neonatal Medicine Alliance,with altitude gradients divided into 4 categories:800 m,1 900 m,2 400 m,and 3 500 m,with an anticipated sample size of 170 neonates per altitude gradient.This multicenter prospective cohort study aims to provide evidence supporting the impact of high-altitude environments on early brain function and metabolism in neonates.[Chinese Journal of Contemporary Pediatrics,2024,26(4):403-409]

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.

Objective:To explore the clinical characteristics of children with septic shock and analyze the drug resistance of blood culture positive bacteria.Methods:The clinical data,positive blood culture strains and drug sensitivity results of 127 children with septic shock admitted to the Department of Intensive Care Medicine of Hunan Children's Hospital from September 2015 to August 2021 were retrospectively analyzed.Results:A total of 134 strains of bacteria or fungi were isolated from the blood culture samples of 127 children with septic shock,and gram-negative strains were the main ones,accounting for 67.16% (90/134).Haemophilus influenzae and Escherichia coli were the main gram-negative bacteria,accounting for 38.81% (52/134) and 20.15% (27/134)，respectively,while Streptococcus pneumoniae was the main gram-positive bacteria,accounting for 8.21% (11/134),and Candida albicans was the main fungus,accounting for 10.45% (14/134).The number of white blood cells,the levels of serum C-reactive protein,procalcitonin,venous blood sugar and arterial blood lactic acid in patients were all significantly higher than normal values,and the white blood cells count and neutrophil percentage in gram-positive bacterial infections were significantly higher than those with gram-negative bacterial infections and fungal infections( P<0.05).Procalcitonin increased most obviously when infected by gram-negative bacteria,and the difference was statistically significant ( P<0.05).Gram-positive strains were sensitive to vancomycin,teicoplanin,and linezolid,but only 50% of Streptococcus pneumoniae were sensitive to penicillin.Gram-negative strains had relatively high drug resistance,among which Klebsiella pneumoniae were only highly resistant to imipenem,cilastatin and levofloxacin,reaching 50%.Haemophilus influenzae was resistant to cephalosporins and β-amides enzyme antibiotic,and the drug sensitivity rate of lactamase antibiotics was high,with a resistance rate of 50% only to ampicillin,cefuroxime,amikacin,and compound sulfamethoxazole.There were not many fungal strains,and most antifungal drugs were effective against blood culture-positive fungi. Conclusion:The main pathogens of infection in children with septic shock are gram-negative bacteria,and have high resistance to general antibiotics.We should pay attention to their drug resistance when using antibiotics empirically.