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.

Hypoxemia is a common complication of pneumonia, asthma, and bronchopulmonary dysplasia in children.Rapid identification of hypoxemia is of great significance for the disposal and management of critical children.Pulse oximetry is recognized by the World Health Organization as the best way to monitor hypoxemia in children, and it can monitor pulse oxygen saturation noninvasively and continuously.Based on the related literature at home and abroad, combined with the clinical needs of pediatrics, the " Expert consensus on clinical application of pulse oximetry in children" is formulated to improve the understanding of pediatricians and nurses on the application in pediatric clinical practice, principle, operation techniques, and limitations of pulse oximetry.

Objective:To investigate the knowledge, attitudes, and practices (KAP) of pulse oximetry among pediatric healthcare providers in China and analyze the factor influencing the KAP.Methods:A self-developed questionnaire was used for an online research on the KAP of 11 849 pediatric healthcare providers from 31 provinces, autonomous regions, and municipalities of China from March 11 to 14, 2022.The factors influencing the KAP of pulse oximetry among pediatric healthcare providers were examined by Logistic regression. Results:The scores of KAP, of pulse oximetry were 5.57±0.96, 11.24±1.25 and 11.19±4.54, respectively.The corresponding scoring rates were 69.61%, 74.95%, and 55.99%, respectively. Logistic regression results showed that the gender and working years of pediatric healthcare providers, the region they were located, and whether their medical institution was equipped with pulse oximeters were the main factors affecting the knowledge score (all P<0.05). Main factors influencing the attitude score of pediatric healthcare providers included their knowledge score, gender, educational background, working years, region, medical institution level, and whether the medical institution was equipped with pulse oximeters (all P<0.05). For the practice score, the main influencing factors were the knowledge score, gender, age, and whether the medi-cal institution was equipped with pulse oximeters (all P<0.05). Conclusions:Chinese pediatric healthcare providers need to further improve their knowledge about and attitudes towards pulse oximetry.Pulse oximeters are evidently under-used.It is urgent to formulate policies or guidelines, strengthen education and training, improve knowledge and attitudes, equip more institutions with pulse oximeters, and popularize their application in medical institutions.

Objective:To explore the consistency of peripheral whole blood and venous serum procalcitonin (PCT) levels, and the value of peripheral whole blood PCT in evaluating pediatric bacterial infection.Methods:This multicenter cross-sectional parallel control study was conducted in 11 children′s hospital. All the 1 898 patients older than 28 days admitted to these hospitals from March 2018 to February 2019 had their peripheral whole blood and venous serum PCT detected simultaneously with unified equipment, reagent and method. According to the venous serum PCT level, the patients were stratified to subgroups. Analysis of variance and chi-square test were used to compare the demographic characteristics among groups. And the correlation between the peripheral blood and venous serum PCT level was investigated by quantitative Pearson correlation analysis.The PCT resultes were also converted into ranked data to further test the consistency between the two sampling methods by Spearman′s rank correlation test. Furthermore, the ranked data were converted into binary data to evaluate the consistency and investigate the best cut-off of peripheral blood PCT level in predicting bacterial infection.Results:A total of 1 898 valid samples were included (1 098 males, 800 females),age 27.4(12.2,56.7) months. There was a good correlation between PCT values of peripheral whole blood and venous serum ( r=0.97 , P<0.01). The linear regression equation was PCT?venous serum=0.135+0.929×PCT peripheral whole blood. However, when stratified to 5 levels, PCT results showed diverse and unsatisfied consistency between the two sampling methods ( r=0.51-0.92, all P<0.01). But after PCT was converted to ordinal categorical variables, the stratified analysis showed that the coincidence rate of the measured values by the two sampling methods in each boundary area was 84.9%-97.1%. The dichotomous variables also showed a good consistency (coincidence rate 96.8%-99.3%, Youden index 0.82-0.89). According to the severity of disease, the serum PCT value was classified into 4 intervals（<0.5、0.5-<2.0、2.0-<10.0、≥10.0 μg/L）, and the peripheral blood PCT value also showed a good predictive value (AUC value was 0.991 2-0.997 9). The optimal cut points of peripheral whole blood PCT value 0.5、1.0、2.0、10.0 μg/L corresponding to venous serum PCT values were 0.395, 0.595, 1.175 and 3.545 μg/L, respectively. Conclusions:There is a good correlation between peripheral whole blood PCT value and the venous serum PCT value, which means that the peripheral whole blood PCT could facilitate the identification of infection and clinical severity. Besides, the sampling of peripheral whole blood is simple and easy to repeat.

Acid protease, an important aspartic protease, has been widely used in food, pharmaceutical and tanning industries. To promote the research and application of acid protease, an acid protease gene (pepA) from Aspergillus oryzae was obtained from fermented soy based on metagenome sequencing, and then cloned and transformed into Pichia pastoris GS115 for heterologous expression. The characteristic of recombinant PepA was also investigated. The activity of acid protease in the culture supernatant of P. pastoris was 50.62 U/mL. The molecular mass of PepA was about 50 kDa, and almost no other proteins in the supernatant were observed, as shown by SDS-PAGE. The optimum pH and temperature of PepA were determined as pH 4.5 and 50 ℃. Mn²⁺ and Cu²⁺ enhanced the activity of PepA, whereas Fe³⁺, Fe²⁺ and Ca² had inhibitory effects on its activity. The above findings can provide guidance for heterologous expression and industrial application of acid protease from Aspergillus oryzae.
Aspergillus oryzae ; Cloning, Molecular ; Endopeptidases ; Hydrogen-Ion Concentration ; Pichia ; Recombinant Proteins ; Temperature

This is a commentary on a recent meta-analysis regarding to the associations between calcium and vitamin D supplementation on fracture incidence.Calcium and vitamin D supplementation is the simplest and the least expensive way among the available preventive strategies for osteoporosis management.The regional feature and rule of individualized medication should be considered.

Objective To investigate the lead and cadmium contents in different sampling sites from full term neonatal placenta and to explore the role of placental sample in the evaluation of intrauterine heavy metals exposure.Methods The placentas from 30 healthy full term neonates were collected from the West China Second Hospital of Sichuan University during May and June 2016.Each placenta fetal side was divided into the left and right parts with the umbilical vein in the umbilical cord cross-section as the 12 o'clock direction.The villus lobular tissue samples were taken from the 1/4 radius in left part (site A) and 3/4 radius in the right part (site B).The graphite furnace atomic absorption spectrometry was used to detect the lead and cadmium contents in the samples.The elements contents in the site A and B were performed the paired t-test and correlation analysis.Results The mean contents of lead and cadmium in dry weight sample at placental site A were 91.8 and 66.7μg/kg which at the site B were 88.9 and 64.8 μg/kg respectively.The lead and cadmium contents at these two sites presented the positive correlation,the coefficients were 0.98 and 0.97 respectively,whereas the difference in contents between the tissues from different placental sites had no statistical significance.Conclusion The lead and cadmium contents of villus lobular tissue in the central part of placenta fetal side (1/4-3/4 radius area) are basically consistent,which is a reliable indicator for evaluating the intrauterine heavy metals exposure.

Circular RNA (circRNA) is a widely present endogenous noncoding RNA that is covalently bonded at the 3' and 5' ends via trans-splicing to form a closed-loop structure with high stability, biological evolutionary conservatism,and tissue expression specificity. CircRNA has important biological functions, such as playing the role of microRNA (miRNA) sponge, regulating the expression of a par-ent gene, and improving transcription and translation levels. In gastrointestinal tumor, circRNA mainly plays the role of miRNA sponge, which affects the proliferation, differentiation, apoptosis, and invasion of cancer cells. In addition, circRNA was specifically expressed in the tumor, and the expression level significantly differs from that of paracancer. Therefore, a highly conserved and stable circRNA se-quence is expected to be an early diagnosis and prognostic marker for gastrointestinal tumor. In this study, we review research advanc-es on circRNA and its relationship with gastrointestinal cancers (esophageal, gastric, colorectal, and liver cancers).

OBJECTIVECongenital heart defect is one of the most common birth defects. The isolated ventricular septal defect (VSD) has higher morbidity, and spontaneous closure may occur. Previously many studies about the prognosis of ventricular septal defect in childhood were conducted; in contrast, few studies on evolution and prognosis of ventricular septal defect from fetus to postnatal life have been available. This research aimed to determine the evolution of isolated ventricular septal defect during the period of fetus and postnatal life, and analyze the association between the diameter or location of VSD and the spontaneous closure of VSD.

METHODAll pregnant women seen at the prenatal diagnosis center of the West China Second Hospital were recruited. From June 2011 to June 2014, these participants underwent the fetal 2-dimensional and color Doppler echocardiographic examinations, and the fetuses with isolated VSD were included in the study, and those with other malformations or abnormal chromosome were excluded. This study was a prospective and longitudinal research. These fetuses were followed-up until the VSD closed spontaneously, or were surgically repaired or percutaneously closed. Outcomes of all the cases were recorded.

RESULTThere were 234 fetuses with isolated VSD who were recruited in our research cohort. Twelve of 234 lost to follow-up, 5 of 234 were still in uterus. Totally 217 fetuses were followed up. One hundred eighty-nine of 217 (87.1%) cases were delivered. The pregnancies were terminated in 28 of 217 (12.9%) cases. Ten cases died after birth. Of the 179 delivered cases, the rate of VSD spontaneous closure was 45.2% (81/179), the VSD of 49 cases (27.4%, 49/179) spontaneously closed in uterus. The VSD of 17.9% (32/179) cases spontaneously closed after birth and those of 75% (24/32) cases closed in the first year of life. Furthermore, these participants were divided into 3 groups according to the diameter of VSD in fetus. There were 87 cases in ≤ 2.0 mm group, 51 spontaneously closed (59%, 51/87) and 30 of 84 spontaneously closed (36%, 30/84) in 2.1-5.0 mm group. There were no spontaneous closure in > 5.0 mm group. There was a significant difference in spontaneous closure rate between the 3 groups (χ(2) = 15.200, P = 0.001). Nevertheless, these participants were divided into 2 groups according to the location of VSD in fetus (perimembrane VSD (P-VSD) group and muscular VSD (M-VSD) group). There were 152 cases in P-VSD group, 69 spontaneously closed (45.4%, 69/152) and 12 of 27 spontaneously closed (44%, 12/27) in M-VSD group. There was no significant difference in spontaneous closure between P-VSD and M-VSD (χ(2) = 0.008, P = 0.950).

CONCLUSIONThere was a high spontaneous closure rate of VSD in the period of late pregnancy. The most of postnatal VSD were spontaneously closed within one year of age. The spontaneous closure rates of fetal VSD with different diameter were different. The spontaneous closure rate of VSD with smaller diameter was higher.

China ; Chromosome Aberrations ; Echocardiography, Doppler, Color ; Female ; Fetal Diseases ; diagnostic imaging ; pathology ; Fetus ; Heart Septal Defects, Ventricular ; diagnostic imaging ; pathology ; Humans ; Lost to Follow-Up ; Pregnancy ; Prenatal Diagnosis ; Prognosis ; Prospective Studies

correlation with cross-sectional area and negative correlation with bucking ratio. The effect of fat mass on hip geometric parameters at the three regions was inconsistent. (3) Fat mass and percentage of body fat ( Fat%) showed negative correlation with cross-sectional area and average cortical thickness and positive correlation with bucking ratio in young group. However, the negative contribution produced by fat mass and Fat% to hip geometric structure became weaker gradually in middle-aged and older groups. ( 4 ) Limb lean mass yielded the largest positive contribution to cross-sectional area and average cortical thickness at all three regions in young group. However, the contribution produced by trunk lean mass became the largest positive contribution to cross-sectional area and average cortical thickness in older group. Conclusions Among all the body composition parameters, hip BMD has showed the most marked correlation with hip geometric structure. Lean mass is ranked the second in the correlation. The impacts of fat mass and lean mass on hip geometry are changing with aging and their different tissue distributions.