OBJECTIVE: To investigate the impact of bone mass and volume of low-density zones beneath the tibial plateau on the maximum von Mises stresses experienced by the cartilage and meniscus in the knee joint. METHODS: The study included one healthy adult volunteer, from whom CT scans were obtained, and one patient diagnosed with knee osteoarthrisis (KOA), for whom X-ray films were acquired. A static model of the knee joint featuring a low-density zone was established based on a normal knee model. In the finite element analysis, axial loads of 1 000 N and 1 800 N were applied to the weight-bearing region of the upper surface of the femoral head for model validation and subsequent finite element studies, respectively. The maximum von Mises stresses in the femoral cartilage, as well as the medial and lateral tibial cartilage and menisci, were observed, and the stress percentage of the medial and lateral components were concurrently analyzed. Additionally, HE staining, as well as alkaline magenta staining, were performed on the pathological specimens of patients with KOA in various low-density regions. RESULTS: The results of model validation indicated that the model was consistent with normal anatomical structures and correlated with previous calculations documented in the literature. Static analysis revealed that the maximum von Mises stress in the medial component of the normal knee was the lowest and increased with the advancement of the hypointensity zone. In contrast, the lateral component exhibited an opposing trend, with the maximum von Mises stress in the lateral component being the highest and decreasing as the hypointensity zone progressed. Additionally, the medial component experienced an increasing proportion of stress within the overall knee joint. HE staining demonstrated that the chondrocyte layer progressively deteriorated and may even disappear as the hypointensity zone expanded. Furthermore, alkaline magenta staining indicated that the severity of microfractures in the trabecular bone increased concurrently with the expansion of the hypointensity zone. CONCLUSION The presence of subtalar plateau low-density zone may aggravate joint degeneration. In clinical practice, it is necessary to pay attention to the changes in the subtalar plateau low-density zone and actively take effective measures to strengthen the bone status of the subtalar plateau low-density zone and restore the complete biomechanical function of the knee joint, in order to slow down or reverse the progression of osteoarthritis.
Humans ; Finite Element Analysis ; Knee Joint/physiology* ; Tibia/anatomy & histology* ; Cartilage, Articular/physiology* ; Menisci, Tibial/physiopathology* ; Tomography, X-Ray Computed ; Osteoarthritis, Knee/diagnostic imaging* ; Weight-Bearing ; Bone Density ; Adult ; Stress, Mechanical ; Male ; Middle Aged ; Biomechanical Phenomena ; Female

Objective:To preliminarily explore the association of pregnancy factors with cow's milk protein allergy in infants.Methods:This study was based on data from a subcohort of a study called ge-netic susceptibility to cow's milk allergy in Chinese children,including infants born in Peking University People's Hospital between March 1,2020,and December 31,2020.The infants were divided into a cow's milk protein allergy(CMPA)group and a control group according to whether they had developed cow's milk protein allergy at the age of 1 year.We retrospectively collected the clinical data of infants and their mothers before and during pregnancy,and analyzed the association of multiple factors during pregnancy with cow's milk protein allergy in infants.Results:A total of 278 infants were enrolled in this study,including 52 infants with CMPA and 226 infants without CMPA.Among them,there were 143 boys and 135 girls.The proportion of male infants in the CMPA group(69.2％)was higher than that in the control group(47.3％),and the difference was statistically significant(P=0.004).There were no significant differences in the distribution of birth weight,gestational age at birth,low-birth-weight in-fants,premature,umbilical cord entangle neck,and neonatal asphyxia between the CMPA group and the control group(P＞0.05).The proportion of mothers complicated with autoimmune diseases,anemia or antibiotics exposure during pregnancy in the CMPA group was higher than that in the control group,and there were statistical differences between the two groups(P＜0.05).There was no significant difference in the distribution of other pregnancy complications between the two groups(P＞0.05),such as eclamp-sia/preeclampsia,chronic hypertension/gestational hypertension,diabetes/gestational diabetes,thyroid diseases,and so on.There was no significant difference in the overall distribution of some blood routine indexes during pregnancy between the CMPA group and the control group(P＞0.05).Multivariate Lo-gistic regression analysis showed that male infant,mothers complicated with autoimmune diseases or ane-mia,antibiotic exposure during pregnancy were independent risk factors for cow's milk protein allergy.Conclusion:Male infant,mothers complicated with autoimmune diseases or anemia,antibiotic exposure during pregnancy were independent risk factors for cow's milk protein allergy.

BACKGROUND:Periprosthetic joint infection is one of the most unwanted complications for surgeons and patients after arthroplasty,and its recalcitrance and intractability have always been a headache for arthroplasty surgeons. OBJECTIVE:To review the latest domestic and international clinical treatments used in the treatment of periprosthetic joint infection after hip and knee arthroplasty in recent years,including antibiotic treatment,surgical treatment,biological treatment and Chinese medicine treatment,to promote the research progress in the treatment of periprosthetic joint infection in China. METHODS:The literature from January 2000 to October 2022 on CNKI,WanFang,VIP,and PubMed was retrieved by the first author.762 articles were obtained by reading the titles for initial screening,then 194 articles were obtained by reading the abstracts and excluding studies with duplicate contents,low data reliability,and outdated views.Finally,88 articles were included through intensive reading of the original text. RESULTS AND CONCLUSION:(1)Combined antibiotic regimens may help eradicate the infection in the treatment of periprosthetic infections.(2)Two-stage revision remained the golden indicator for the treatment of periprosthetic infection.(3)One-stage revision lacked large-sample clinical studies and required more clinical observation.(4)Phage therapy and newer drug delivery systems in biological therapy had been applied in small amounts in the clinic,showing their advantages in the prevention and eradication of periprosthetic infections.(5)Chinese medicine with antibiotics and surgical treatment methods can improve the prevention and treatment of periprosthetic joint infection,but high-level evidence-based medical evidence was lacking.

Objective:To investigate the relationship between gestational weight gain (GWG) in twin pregnancies and adverse perinatal outcomes.Methods:This retrospective study included twin pregnant women with live births at≥25 weeks of gestation and their offspring, who delivered at Peking University People's Hospital from January 2012 to October 2022. Total GWG was standardized according to gestational age and categorized into three groups based on the 2009 Institute of Medicine (IOM) guidelines: insufficient GWG (GWG below IOM recommendations), appropriate GWG (GWG within IOM recommendations), and excessive GWG (GWG above IOM recommendations). Comparisons between data of the three groups used analysis of variance, Kruskal-Wallis test or Bonferroni correction or Chi-square partitions. Multivariable logistic regression models and generalized estimating equations with logistic regression models were used to analyze the independent effects of GWG on maternal and neonatal outcomes. Results:A total of 794 twin pregnant women and their 1 588 live-born neonates were included in the study. There were 360 women (45.3%) with appropriate GWG, 356 (44.8%) with insufficient GWG, and 78 (9.8%) with excessive GWG. Both insufficient and excessive GWG were associated with an increased risk of preterm birth [adjusted ORs of 1.39 (95% CI: 1.04-1.88) and 1.70 (95% CI: 1.05-2.78), respectively]. Insufficient GWG was associated with an increased risk of gestational diabetes mellitus (adjusted OR=1.42, 95% CI: 1.00-2.01) and low birth weight infants (adjusted OR=2.04, 95% CI: 1.57-2.66). Insufficient GWG was also associated with a reduced risk of eclampsia or preeclampsia (adjusted OR=0.50, 95% CI: 0.33-0.75), cesarean section (adjusted OR=0.48, 95% CI: 0.30-0.77), discordant twin growth (adjusted OR=0.56, 95% CI: 0.37-0.85), and large for gestational age infants (adjusted OR=0.46, 95% CI: 0.35-0.61). Excessive GWG was associated with an increased risk of eclampsia or preeclampsia (adjusted OR=2.85, 95% CI: 1.65-4.91), and large for gestational age infants (adjusted OR=2.49, 95% CI: 1.60-3.86), while with a decreased risk of low birth weight infants (adjusted OR=0.42, 95% CI: 0.27-0.65). Conclusions:More than half of the twin pregnancies have GWG outside the recommended range of the IOM guidelines. Both insufficient and excessive GWG are associated with adverse perinatal outcomes, particularly an increased risk of preterm birth.

Purpose: The risk stratification of pediatric anaplastic large cell lymphoma (ALCL) has not been standardized. In this study, new risk factors were included to establish a new risk stratification system for ALCL, and its feasibility in clinical practice was explored. Materials and Methods: On the basis of the non-Hodgkin’s lymphoma Berlin–Frankfurt–Munster 95 (NHL-BFM-95) protocol, patients with minimal disseminated disease (MDD), high-risk tumor site (multiple bone, skin, liver, and lung involvement), and small cell/lymphohistiocytic (SC/LH) pathological subtype were enrolled in risk stratification. Patients were treated with a modified NHL-BFM-95 protocol combined with an anaplastic lymphoma kinase inhibitor or vinblastine (VBL). Results: A total of 136 patients were enrolled in this study. The median age was 8.8 years. The 3-year event-free survival (EFS) and overall survival of the entire cohort were 77.7% (95% confidence interval [CI], 69.0% to 83.9%) and 92.3% (95% CI, 86.1% to 95.8%), respectively. The 3-year EFS rates of low-risk group (R1), intermediate-risk group (R2), and high-risk group (R3) patients were 100%, 89.5% (95% CI, 76.5% to 95.5%), and 67.9% (95% CI, 55.4% to 77.6%), respectively. The prognosis of patients with MDD (+), stage IV cancer, SC/LH lymphoma, and high-risk sites was poor, and the 3-year EFS rates were 45.3% (95% CI, 68.6% to 19.0%), 65.7% (95% CI, 47.6% to 78.9%), 55.7% (95% CI, 26.2% to 77.5%), and 70.7% (95% CI, 48.6% to 84.6%), respectively. At the end of follow-up, one of the five patients who received maintenance therapy with VBL relapsed, and seven patients receiving anaplastic lymphoma kinase inhibitor maintenance therapy did not experience relapse. Conclusion This study has confirmed the poor prognostic of MDD (+), high-risk site and SC/LH, but patients with SC/LH lymphoma and MDD (+) at diagnosis still need to receive better treatment (ClinicalTrials.gov number, NCT03971305).

Objective:To explore the clinical features of patients with syndrome of intracranial hypotension (SIH) complicated by bilateral chronic subdural hematoma (CSDH).Methods:A case-control study was conducted; 16 patients with SIH complicated with bilateral CSDH (SIH group) and 32 patients with bilateral CSDH (non-SIH group) admitted to Department of Neurology and Neurosurgery, Shanghai Tenth People's Hospital Affiliated to Tongji University from January 2016 to October 2020 were selected. The differences of demographic characteristics, initial symptoms, medical history and CT image features between the two groups were compared.Results:(1) In 16 patients from the SIH group, 13 (81.3%) complained of typical postural headache symptoms, 3 (18.6%) showed fake subarachnoid hemorrhage on CT, 80.0% (12/15) showed dural diffuse enhancement on MRI, and 33.3% (5/15) showed signs of brain droop. Spinal MRI showed 27.3% patients (3/11) had signs of intracranial cerebrospinal fluid leakage. Of the 10 patients underwent bilateral trepanation and drainage, 6 experienced postoperative deterioration (4 received multiple additional surgeries including decompressive craniectomy, and 1 severe patient died in hospital after giving up treatment due to malignant tumor). (2) SIH group had significantly younger age, and significantly lower percentages of patients with limb weakness symptoms, hypertension, head trauma histories and increased hematoma pressure during trepanation and drainage, significantly lower age-adjusted comorbidities index, significantly decreased total and differential thickness of bilateral hematoma on CT, significantly shorter disease course, and statistically higher proportion of patients with postural headache and hematoma uniform density than non-SIH group ( P<0.05). Conclusion:According to age, initial symptoms and CT features, bilateral CSDH patients caused by SIH can be identified to a certain extent, and cranial and spinal MRI is recommended for definitive diagnosis of SIH.

OBJECTIVETo study the radiobiological characteristics of a HepG2 cell line with mitochondrial DNA (mtDNA) deletion.

METHODSHepG2 cells were cultured in a medium containing ethidium bromide, acetylformic acid and uracil. The HepG2 cell line with mtDNA deletion (ρ(0)HepG2 cells) were acquired after 30 subcultures by limited dilution cloning. The cell survival was then observed in the absence of acetylformic acid and uracil, and the total mtDNA deletion in the cells was confirmed by PCR. The radiosensitivity of HepG2 and ρ(0)HepG2 cells was evaluated by exposure to gradient doses of 6 MV X ray irradiation. The cell apoptosis was assessed following a 2 Gy X-ray exposure with Hochest33342 staining, and the invasiveness of ρ(0)HepG2 cells was measured by Transwell assay.

RESULTSHepG2 cells could survive 30 subcultures in the presence of ethidium bromide, and massive cell death occurred after removal of acetylformic acid and uracil from the medium. PCR confirmed total mtDNA deletion from ρ(0)HepG2 cells, whose α/β value was significantly lower than that of HepG2 cells. ρ(0)Hep-G2 cells showed an obviously lowered cell apoptosis rate following X-ray exposure with enhanced cell invasiveness.

CONCLUSIONHepG2 cells can be induced by ethidium bromide into ρ(0)HepG2 cells with an increased radiation resistance, anti-apoptosis ability and cell invasiveness.

Apoptosis ; Culture Media ; chemistry ; DNA, Mitochondrial ; genetics ; Ethidium ; chemistry ; Hep G2 Cells ; radiation effects ; Humans ; Radiation Tolerance ; genetics ; Sequence Deletion ; X-Rays

Objective To study the radiobiological characteristics of a HepG2 cell line with mitochondrial DNA (mtDNA) deletion. Methods HepG2 cells were cultured in a medium containing ethidium bromide, acetylformic acid and uracil. The HepG2 cell line with mtDNA deletion (ρ0HepG2 cells) were acquired after 30 subcultures by limited dilution cloning. The cell survival was then observed in the absence of acetylformic acid and uracil, and the total mtDNA deletion in the cells was confirmed by PCR. The radiosensitivity of HepG2 andρ0HepG2 cells was evaluated by exposure to gradient doses of 6 MV X ray irradiation. The cell apoptosis was assessed following a 2 Gy X-ray exposure with Hochest33342 staining, and the invasiveness of ρ0HepG2 cells was measured by Transwell assay. Results HepG2 cells could survive 30 subcultures in the presence of ethidium bromide, and massive cell death occurred after removal of acetylformic acid and uracil from the medium. PCR confirmed total mtDNA deletion fromρ0HepG2 cells, whoseα/βvalue was significantly lower than that of HepG2 cells.ρ0Hep-G2 cells showed an obviously lowered cell apoptosis rate following X-ray exposure with enhanced cell invasiveness. Conclusion HepG2 cells can be induced by ethidium bromide intoρ0HepG2 cells with an increased radiation resistance, anti-apoptosis ability and cell invasiveness.

Objective To study the radiobiological characteristics of a HepG2 cell line with mitochondrial DNA (mtDNA) deletion. Methods HepG2 cells were cultured in a medium containing ethidium bromide, acetylformic acid and uracil. The HepG2 cell line with mtDNA deletion (ρ0HepG2 cells) were acquired after 30 subcultures by limited dilution cloning. The cell survival was then observed in the absence of acetylformic acid and uracil, and the total mtDNA deletion in the cells was confirmed by PCR. The radiosensitivity of HepG2 andρ0HepG2 cells was evaluated by exposure to gradient doses of 6 MV X ray irradiation. The cell apoptosis was assessed following a 2 Gy X-ray exposure with Hochest33342 staining, and the invasiveness of ρ0HepG2 cells was measured by Transwell assay. Results HepG2 cells could survive 30 subcultures in the presence of ethidium bromide, and massive cell death occurred after removal of acetylformic acid and uracil from the medium. PCR confirmed total mtDNA deletion fromρ0HepG2 cells, whoseα/βvalue was significantly lower than that of HepG2 cells.ρ0Hep-G2 cells showed an obviously lowered cell apoptosis rate following X-ray exposure with enhanced cell invasiveness. Conclusion HepG2 cells can be induced by ethidium bromide intoρ0HepG2 cells with an increased radiation resistance, anti-apoptosis ability and cell invasiveness.