BACKGROUND:Currently,treatment method for knee osteoarthritis includes oral medicine,joint cavity drug injection,and physiotherapy,but the curative effect is limited.Existing studies have confirmed that silicon-based bioceramics can promote cartilage and subchondral bone repair and vascular regeneration.OBJECTIVE:To explore the effect of different concentrations of silicon-based bioceramics injected into the knee joint cavity in the treatment of knee osteoarthritis in rats.METHODS:Silicon-based bioceramics-calcium silicate was prepared.Twenty-five SD rats were randomly divided into five groups,with five rats in each group.The healthy group did not receive any intervention,and the modeling group,low-dose calcium silicate group,high-dose calcium silicate group,and saline group used anterior cruciate ligament transection to establish bilateral knee osteoarthritis models.Four weeks after modeling,0.05 mL of 50 and 100 mg/mL calcium silicate solution were injected into the knee joint cavity in the low-dose calcium silicate group and high-dose calcium silicate group,respectively,and 0.05 mL of saline was injected into the knee joint cavity in the saline group,once a week for 4 consecutive weeks.In the fifth week of administration,bilateral knee joint Micro-CT detection,knee joint cartilage hematoxylin-eosin staining,and modified Mankin score were performed.RESULTS AND CONCLUSION:(1)Micro-CT quantitative analysis showed that compared with the healthy group,the volume fraction and number of trabeculae of the medial tibial plateau in the modeling group decreased(P＜0.05),and the separation of trabeculae increased(P＜0.05).Compared with the modeling group,the volume fraction and number of trabeculae of the medial tibial plateau in the low-dose calcium silicate group and the saline group increased(P＜0.05),and the separation of trabeculae decreased(P＜0.05).(2)Hematoxylin-eosin staining showed that the cartilage surface of the healthy group and the low-dose calcium silicate group was relatively smooth and flat,the chondrocytes were evenly distributed,without clustered chondrocytes,the tide line was complete,and the staining was uniform;the cartilage surface of the high-dose calcium silicate group was slightly uneven,the middle and deep cells were disordered,with a small number of clustered chondrocytes,the tide line was discontinuous,and the staining was uneven;the cartilage surface of the saline group and the modeling group was obviously rough,the cells were disordered,with a large number of clustered chondrocytes,the tide line disappeared,and the staining was uneven.The modified Mankin score of the healthy group was lower than that of the high-dose calcium silicate group,the saline group,and the modeling group(P＜0.05).The modified Mankin score of the high-dose calcium silicate group and the low-dose calcium silicate group was lower than that of the saline group and the modeling group(P＜0.05).(3)The results show that calcium silicate knee joint injection has a certain effect in the treatment of knee osteoarthritis.Compared with 100 mg/mL calcium silicate solution,50 mg/mL calcium silicate solution can promote the recovery of subchondral bone and cartilage.

BACKGROUND:Currently,treatment method for knee osteoarthritis includes oral medicine,joint cavity drug injection,and physiotherapy,but the curative effect is limited.Existing studies have confirmed that silicon-based bioceramics can promote cartilage and subchondral bone repair and vascular regeneration.OBJECTIVE:To explore the effect of different concentrations of silicon-based bioceramics injected into the knee joint cavity in the treatment of knee osteoarthritis in rats.METHODS:Silicon-based bioceramics-calcium silicate was prepared.Twenty-five SD rats were randomly divided into five groups,with five rats in each group.The healthy group did not receive any intervention,and the modeling group,low-dose calcium silicate group,high-dose calcium silicate group,and saline group used anterior cruciate ligament transection to establish bilateral knee osteoarthritis models.Four weeks after modeling,0.05 mL of 50 and 100 mg/mL calcium silicate solution were injected into the knee joint cavity in the low-dose calcium silicate group and high-dose calcium silicate group,respectively,and 0.05 mL of saline was injected into the knee joint cavity in the saline group,once a week for 4 consecutive weeks.In the fifth week of administration,bilateral knee joint Micro-CT detection,knee joint cartilage hematoxylin-eosin staining,and modified Mankin score were performed.RESULTS AND CONCLUSION:(1)Micro-CT quantitative analysis showed that compared with the healthy group,the volume fraction and number of trabeculae of the medial tibial plateau in the modeling group decreased(P＜0.05),and the separation of trabeculae increased(P＜0.05).Compared with the modeling group,the volume fraction and number of trabeculae of the medial tibial plateau in the low-dose calcium silicate group and the saline group increased(P＜0.05),and the separation of trabeculae decreased(P＜0.05).(2)Hematoxylin-eosin staining showed that the cartilage surface of the healthy group and the low-dose calcium silicate group was relatively smooth and flat,the chondrocytes were evenly distributed,without clustered chondrocytes,the tide line was complete,and the staining was uniform;the cartilage surface of the high-dose calcium silicate group was slightly uneven,the middle and deep cells were disordered,with a small number of clustered chondrocytes,the tide line was discontinuous,and the staining was uneven;the cartilage surface of the saline group and the modeling group was obviously rough,the cells were disordered,with a large number of clustered chondrocytes,the tide line disappeared,and the staining was uneven.The modified Mankin score of the healthy group was lower than that of the high-dose calcium silicate group,the saline group,and the modeling group(P＜0.05).The modified Mankin score of the high-dose calcium silicate group and the low-dose calcium silicate group was lower than that of the saline group and the modeling group(P＜0.05).(3)The results show that calcium silicate knee joint injection has a certain effect in the treatment of knee osteoarthritis.Compared with 100 mg/mL calcium silicate solution,50 mg/mL calcium silicate solution can promote the recovery of subchondral bone and cartilage.

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 accurately measure human energy metabolism with high temporal resolution, a respiratory gas analysis system was designed using a breath-by-breath approach. METHODS: Firstly, indirect calorimetry was employed in respiratory gas analysis to measure the respiratory flow and concentration signals in real-time. Secondly, oxygen consumption QO2 and carbon dioxide production QCO2 were calculated through respiratory characteristic alignment and respiratory signal segmentation. Finally, metabolic indexes were calculated according to the Weir formula. Furthermore, a controlled trial was formulated for validation comparisons with the MGC ULTIMA SYSTEM PFX CARDIO2. RESULTS: The results indicate that the data points of metabolic indexes measured by this system all fall within the confidence interval when compared with those of the MGC. CONCLUSION The system has high consistency with the MGC measurement results. Thus, the system can accurately measure metabolism in real-time and provide data support for clinical nutrition assessment and therapy.
Humans ; Energy Metabolism ; Breath Tests/instrumentation* ; Calorimetry, Indirect/instrumentation* ; Equipment Design

To introduce and analyze guideline terminology related to clinical question formulation, evidence retrieval and appraisal, and recommendation development.

Objective:To investigate the correlation between the density and volume of left atrial-epicardial adipose tissue(LA-EAT)and the occurrence and severity of atrial fibrillation(AF)in elderly patients.Methods:This was a retrospective case-control study.A total of 197 elderly patients with AF and 82 patients with sinus rhythm who were hospitalized in the Department of Cardiology and Geriatric Cardiology of the First Affiliated Hospital of Nanjing Medical University from June 2023 to July 2024.were selected.The AF group was further divided into paroxysmal AF(PAF)subgroup(111 cases)and persistent AF(PeAF)subgroup(86 cases). The density and volume of LA-EAT in all patients were meansured by coronary artery enhanced CT or left atrial enhanced CT.The differences in LA-EAT density, volume and related data among the 3 groups were compared, and their relationship with different severity of senile AF was analyzed.Logistic regression was used to analyze whether LA-EAT density and volume were risk factors for senile AF.The predictive value of LA-EAT density and volume for AF in the elderly was compared throuh restricted cubic spline analysis.Results:The average LA-EAT density in the sinus rhythm group, PAF group and PeAF group was -82.75(-87.15, -79.63), -81.70(-85.55, -75.85)and -80.45(-83.40, -76.10)HU, respectively; the standard deviation of density was 34.70(31.93, 36.28), 36.20(34.30, 37.65)and 35.45(33.63, 37.28)HU, respectively; the LA-EAT volume was 23 483.40(13 964.10, 31 645.53), 25 112.20(18 479.10, 36 917.50)and 37 836.50(25 933.80, 45 537.90)mm 3, respectively.The LA-EAT density and volume in the PAF group and PeAF group were higher than those in the sinus rhythm group(all P<0.05). The LA-EAT volume in the PeAF group was greater than that in the PAF group( P<0.001), but there was no significant difference in LA-EAT density between the two groups( P>0.05). Multivariate logistic regression analysis showed that LA-EAT density and volume, left atrial diameter(LAD)and body mass index(BMI)were the independent risk factors for AF in the elderly( P<0.05). Conclusions:LA-EAT density and volume are significantly correlated with occurrence of senile AF, and show a positive dose-response relationship.LA-EAT volume is significantly related to the severity of AF( P<0.05), while the density is not significantly related to it( P>0.05).

Objective:To design an inspection system for quality of metabolism tester based on alcohol combustion mode for human body,so as to realize assessment for accuracy degree of human metabolism tester.Methods:According to the specific indicators that were measured by the metabolism tester for human body,a simulation of bidirectional controllable flow and a simulation of component concentration of exhaled breath were designed and realized.Then,the ratio of alcohol consumption to oxygen consumption and carbon dioxide production were calculated by the formula of alcohol combustion.Finally,the metabolic indexes(volume of gas flow,oxygen consumption,dioxide carbon production,rate of energy metabolism,respiratory quotient)that were outputted by the inspection system for quality were calculated according to Weir formula.Furthermore,the verification for precision of simulation modules of exhale and inhalation,and weighing device module was carried out,and an application test of inspection system for quality was also carried out.Results:The errors of the volume of gas flow and alcohol consumption that were outputted by simulation modules of exhale and inhalation,and weighing device module were all within±1%,and the errors between the reference value of the metabolic index of the inspection system for quality and the actually measured value of the metabolic index of the hood calorimeter were all within 10%.Conclusion:There was higher consistency between inspection system for quality of metabolism tester for human body and the actual measurement data of calorimeter,which can better simulate the process of respiratory metabolism of human body,and provide standardized testing means for the performance verification of metabolic tester.

Telepsychiatry,as an innovative healthcare model that utilizes remote communication technology for the diagnosis,treatment,counseling,and management of mental illnesses,not only has seen rapid development during the coronavirus disease 2019 pandemic,but also has played a crucial role in alleviating the global shortage of mental health resources.In recent years,with the rapid advancement of digital technology,emerging technologies such as artificial intelligence,virtual reality,and wearable digital health devices have demonstrated broad application prospects in the field of telepsychiatry.This article systematically reviews the relevant literatures on telepsychiatry,delving into its concepts,major tools,and clinical applications,providing insights for researchers and decision-makers in the field,and ultimately promoting the widespread adoption of telepsychiatry.

Sarcopenia is an age-related syndrome characterized by progressive and widespread loss of skeletal muscle mass and/or decline in muscle function.Its incidence increases year by year with aging and is influenced by multiple factors,including genetic background,lifestyle,nutritional status,and chronic diseases.Recent studies have revealed a significant correlation between sarcopenia and chronic coronary syndromes(CCS),not only in terms of the frequency of occurrence but also the se-verity of the conditions.Moreover,sarcopenia and CCS share common pathogenic mechanisms,en-compassing various pathophysiological processes such as chronic inflammation,oxidative stress,apop-tosis,and insulin resistance.This article aimed to review the current research progress on comorbidity relationship between sarcopenia and CCS,explore their shared pathophysiological basis,and discuss their impacts on clinical prognosis.

Objective To sort,summarize,and introduce key terms related to guideline reporting,evaluation,dissemination,implementation,and updating.Methods We systematically searched guideline de-velopment manuals and methodological literature from database inception to October 25,2024.Terms related to guideline reporting,updating,evaluation,and implementation were extracted,standardized,and finalized through a structured consensus process.Results A total of 13 guideline manuals and 32 methodological articles were included,yielding 14 core terms with standardized definitions.Conclusions This article introduces key terms such as reporting standards,external review,and research gaps across guideline development phases to promote concept application and deepen readers'understanding of guideline development.