Chronic ACLD Knees with Early Developmental Cartilage Lesions Exhibited Increased Posterior Tibial Translation during Level Walking

OBJECTIVE

Early articular cartilage lesion (CL) is a vital sign in the onset of posttraumatic knee osteoarthritis (PTOA) in patients with anterior cruciate ligament deficiency (ACLD). Researchers have suggested that altered kinematics could accelerate CLs and, therefore, lead to the onset of PTOA. However, little is known about whether specific knee kinematics exist that lead to early CL in chronic ACLD knees. Level walking is the most frequent and relevant in vivo activity, which greatly impacts knee health. We hypothesized that the knee kinematics during level walking in chronic ACLD knees with early tibiofemoral CL would significantly differ from those of chronic ACLD knees without early tibiofemoral CL.

METHODS

Thirty patients with a chronic ACLD history, including 18 subjects with CLs and 12 subjects without CLs, and 35 healthy control subjects were recruited for the study from July 2020 to August 2022. The knee kinematic data during level walking were collected using a three-dimensional motion analysis system. The kinematic differences between groups were compared using statistical parametric mapping with one dimension for One-Way ANOVA. The cartilage statuses of the ACLD knees were assessed via MRI examination. The CLs distribution of subjects was evaluated using a modified Noyes scale and analyzed by chi-square tests.

RESULTS

ACLD knees with CLs had significantly greater posterior tibial translation (7.7-8.0mm, 12%-18% gait cycle GC, p = 0.014) compared to ACLD knees without CLs during level walking. ACLD knees with CLs had greater posterior tibial translation (4.6-5.5mm, 0%-23% GC, p < 0.001; 5.8-8.0mm, 86%-100% GC, p < 0.001) than healthy controls during level walking. In the group of ACLD knees with CLs, CL is mainly located in the back of the tibia plateau and front of load bearing area of the medial femoral condyle (p < 0.05).

CONCLUSION

Chronic anterior cruciate ligament deficient knees with cartilage lesions have increased posterior tibial translation compared to anterior cruciate ligament deficient knees without cartilage lesions and healthy subjects. The posterior tibial translation may play an important role in knee cartilage degeneration in ACLD knees. The increased posterior tibial translation and cartilage lesion characteristics may improve our understanding of the role of knee kinematics in cartilage degeneration and could be a helpful potential reference for anterior cruciate ligament deficient therapy, such as physical training to improve abnormal kinematic behavior.

Transcriptomic analyses and machine-learning methods reveal dysregulated key genes and potential pathogenesis in human osteoarthritic cartilage

Aims

This study aimed to explore the biological and clinical importance of dysregulated key genes in osteoarthritis (OA) patients at the cartilage level to find potential biomarkers and targets for diagnosing and treating OA.

Methods

Six sets of gene expression profiles were obtained from the Gene Expression Omnibus database. Differential expression analysis, weighted gene coexpression network analysis (WGCNA), and multiple machine-learning algorithms were used to screen crucial genes in osteoarthritic cartilage, and genome enrichment and functional annotation analyses were used to decipher the related categories of gene function. Single-sample gene set enrichment analysis was performed to analyze immune cell infiltration. Correlation analysis was used to explore the relationship among the hub genes and immune cells, as well as markers related to articular cartilage degradation and bone mineralization.

Results

A total of 46 genes were obtained from the intersection of significantly upregulated genes in osteoarthritic cartilage and the key module genes screened by WGCNA. Functional annotation analysis revealed that these genes were closely related to pathological responses associated with OA, such as inflammation and immunity. Four key dysregulated genes (cartilage acidic protein 1 (CRTAC1), iodothyronine deiodinase 2 (DIO2), angiopoietin-related protein 2 (ANGPTL2), and MAGE family member D1 (MAGED1)) were identified after using machine-learning algorithms. These genes had high diagnostic value in both the training cohort and external validation cohort (receiver operating characteristic > 0.8). The upregulated expression of these hub genes in osteoarthritic cartilage signified higher levels of immune infiltration as well as the expression of metalloproteinases and mineralization markers, suggesting harmful biological alterations and indicating that these hub genes play an important role in the pathogenesis of OA. A competing endogenous RNA network was constructed to reveal the underlying post-transcriptional regulatory mechanisms.

Conclusion

The current study explores and validates a dysregulated key gene set in osteoarthritic cartilage that is capable of accurately diagnosing OA and characterizing the biological alterations in osteoarthritic cartilage; this may become a promising indicator in clinical decision-making. This study indicates that dysregulated key genes play an important role in the development and progression of OA, and may be potential therapeutic targets.

Do we have to pursue complete reduction after PVA in osteoporotic vertebral compression fractures: a finite element analysis

BACKGROUND

Consensus regarding the optimal amount of bone cement and vertebral height in the treatment of osteoporotic vertebral compression fractures (OVCFs) is lacking. Our purpose was to explore the optimal amount of bone cement and vertebral height in OVCF after percutaneous vertebral augmentation (PVA).

METHODS

A three-dimensional finite element model of the L1-L3 segments was constructed from CT scans of aging osteoporosis patients. Four different postoperative vertebral height models were simulated according to Genant semiquantitative grades 0, 1, 2, and 3. The volume of bone cement filling ranged from 3 ml to 6 ml. These models evaluated the von Mises stress of injured vertebral bodies, adjacent vertebral bodies and intervertebral discs under flexion, extension, left flexion, and right flexion after PVA.

RESULTS

When the bone cement content was held constant, as the height of the vertebral body decreased, the stress of the L2 vertebral body decreased during left flexion and right flexion, but the stress of the L2 vertebral body increased and decreased during flexion and extension. As the height of the vertebral body decreased, the stress of the L1-L2 intervertebral disc increased. There was no significant change in the stress of other adjacent vertebrae or intervertebral discs. When the Genant grade was 0, 1, or 2 (3 ml and 4 ml), the stress of the overall vertebral body was closest to normal.

CONCLUSIONS

When the height of the vertebral body is restored to the same height, a bone cement filling volume of 3 ml to 6 ml is suitable and will not produce a significant change in the stress of the vertebral body or adjacent vertebral body. As vertebral body height was lost, it may promote the degeneration of the intervertebral disc above the injury vertebrae after PVA. It is appropriate for the height of the vertebral body to return to Genant grade 0 or Genant grade 1 after surgery. When the height of the vertebral body has Genant grade 2 status, it was best to use 3 ml to 4 ml of bone cement filling. Therefore, when treating OVCFs, clinicians do not need to pursue complete reduction of the vertebral body. It is also important to verify the biomechanics results in clinical studies.

Exploration of the Molecular Mechanism of Polygonati Rhizoma in the Treatment of Osteoporosis Based on Network Pharmacology and Molecular Docking

OBJECTIVE

To explore the effective components and mechanism of Polygonati Rhizoma (PR) in the treatment of osteoporosis (OP) based on network pharmacology and molecular docking methods.

METHODS

The effective components and predicted targets of PR were obtained through the Traditional Chinese Medicine Systems Pharmacology and Analysis Platform (TCMSP) database. The disease database was used to screen the disease targets of OP. The obtained key targets were uploaded to the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database for protein-protein interaction (PPI) network analysis. The Database for Annotation, Visualization, and Integrated Discovery (DAVID) was used for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of key targets. Analysis and docking verification of chemical effective drug components and key targets were performed with IGEMDOCK software.

RESULTS

A total of 12 chemically active components, 84 drug target proteins and 84 common targets related to drugs and OP were obtained. Key targets such as JUN, TP53, AKT1, ESR1, MAPK14, AR and CASP3 were identified through PPI network analysis. The results of enrichment analysis showed that the potential core drug components regulate the HIF-1 signaling pathway, PI3K-Akt signaling pathway, estrogen signaling pathway and other pathways by intervening in biological processes such as cell proliferation and apoptosis and estrogen response regulation, with an anti-OP pharmacological role. The results of molecular docking showed that the key targets in the regulatory network have high binding activity to related active components.

CONCLUSIONS

PR may regulate OP by regulating core target genes, such as JUN, TP53, AKT1, ESR1, AR and CASP3, and acting on multiple key pathways, such as the HIF-1 signaling pathway, PI3K-Akt signaling pathway, and estrogen signaling pathway.

Prevalence of hepatitis A viral RNA and antibodies among Chinese blood donors

Like other developing countries, China was reported to have a relatively high seroprevalence of anti-hepatitis A antibodies (anti-HAV). However, no studies have evaluated the prevalence of anti-HAV and HAV RNA among voluntary blood donors with or without elevated serum alanine transaminase (ALT) levels. Anti-HAV antibodies were detected using an enzyme-linked immunosorbent assay, and reverse transcription quantitative polymerase chain reaction was carried out for detection of HAV RNA. In the current study, we analyzed a total of 450 serum samples with elevated ALT levels (≥40 U/L) and 278 serum samples with non-elevated ALT levels. Seroprevalence rates of anti-HAV were 51.6% in donors with elevated ALT and 41.4% in donors with non-elevated ALT; however, none of the samples was positive for HAV RNA. The results of our study showed lower seroprevalence rates of anti-HAV in blood donors (irrespective of ALT levels) than those in published data on Chinese populations. Although donors with elevated ALT had statistically higher prevalence rates of anti- HAV than did those with non-elevated ALT, none of the serum samples had detectable levels of the active virus. In conclusion, our results demonstrate that the transmission of hepatitis A by blood transfusion will occur rarely.

Application of indirect linkage analysis and direct genotyping to hemophilia A carrier detection in Sichuan, China

Hemophilia A (HA) is an inherited X-linked bleeding disorder caused by mutations in the factor VIII gene. Prenatal detection in female carriers from families with HA is important to reduce the number of HA patients. The purpose of this study was to detect carriers in families with HA from Sichuan, China, using linkage analysis and a direct genotyping method. A total of 18 HA families were studied. Using a combination of intron 22 inversion, intron 1 inversion, the BclI polymorphic site in intron 18, the HindIII polymorphic site in intron 19, and dinucleotide CA-repeat markers in introns 1, 13, 22, and 24, we were able to detect HA in 88.9% (16/18) of the families studied. HA was detected in the remaining two families by direct genotyping. This study gave the participants a good understanding of their genetic condition and gave us a preliminary understanding of the prevalence of each mutation in Sichuan HA patients.

Cohn process influences the functional anticoagulant activity of human protein C

Cohn fraction IV (CFIV) is a byproduct of a plasma fractionation process known as the Cohn process. It is an inexpensive source of protein C, retaining about 90% of protein C (PC) in human plasma. We investigated whether PC is affected during the Cohn process and evaluated correlations among coagulant activity, amidolytic activity and PC antigen during the Cohn process. CFIV was redissolved with citrate-buffered saline for 5 h at 4°C, and then centrifuged at 3500 g for 40 min at 4°C. Functional anticoagulant activity was measured with a one-stage coagulation method based on activated partial thromboplastin time. The functional amidolytic activity of PC was determined using chromogenic substrate assay, and measurement of PC antigen was performed by ELISA. In CFIV, anticoagulant activity declined significantly, with a loss of >80%, while amidolytic activity was not significantly altered, compared to PC antigen. Prior to the Cohn process, high-rank correlations were observed in cryosupernatant, with rs = 0.921 for anticoagulant and amidolytic activities (P = 0.009), 0.896 for anticoagulant activity and antigen (P = 0.014) and 0.832 for amidolytic activity and antigen (P = 0.031). After the Cohn process in CFIV, there was also a high correlation between amidolytic activity and antigen (rs = 0.782, P = 0.038). There were no significant correlations between anticoagulant activity and antigen (rs = 0.223, P = 0.653), or anticoagulant and amidolytic activity (rs = 0.236, P = 0.675). We conclude that the Cohn process significantly influences the anticoagulant activity of PC. Compared to the antigen, PC lost greater than 80% of its anticoagulant activity, but retained its amidolytic activity, during the Cohn process.

Expression and fast preparation of biologically active recombinant human coagulation factor VII in CHO-K1 cells

Human coagulation factor VII (FVII) plays an important role in the blood coagulation process and exists in micro amounts in human plasma; therefore, any attempt at the large-scale production of FVII in significant quantities is challenging. The purpose of this study was to express and obtain biologically active recombinant FVII (rFVII) from Chinese hamster ovary K1 (CHO-K1) cells. The full-length FVII cDNA was isolated from a HepG2 cell line and then subcloned in pcDNA3.1 to construct an expression vector, pcDNA-FVII. CHO-K1 cells were transfected with 1 µg pcDNA-FVII. The cell line that stably expressed secretory FVII was screened using 900 µg/mL G418. The FVII copy number in CHO-K1 cells was detected by quantitative polymerase chain reaction (qPCR). The rFVII was purified in ligand affinity chromatography medium. The purified protein was detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot analysis. The biological activity of the purified FVII protein was determined by a prothrombin time assay. Three cell lines that permanently expressed rFVII were screened. The qPCR results demonstrated that each CHO-K1 cell harbored two FVII DNA copies. The SDS-PAGE and Western blot analysis showed that the purified protein was about 50 kDa. The purity of the target protein was 95%. The prothrombin time assay indicated that the FVII-specific activity of rFVII was 2573 ± 75 IU/mg. This method enabled the fast preparation of high-purity rFVII from CHO-K1 cells, and the purified protein had good biological activity.

[A study of ITS sequence as a molecular marker in the phylogeny of Drosophila nasuta subgroup]

A total of 1.1 kb including whole ITS (intertranscribed spacer), part of 5.8S rDNA and 2S rDNA were sequenced. The results reveal that D. pallidifrons, Taxon I and Taxon J share the same sequence, and D. albomicans and D. s. neonasuta have the other same one. Among the sequences, there were a handful of insertions, deletions and substitutions. Insertions and deletions occur mainly between outgroup and ingroups; yet only 1 insertion and 12 deletions were detected in D. niveifrons, and 1 deletion was found in D. s. sulfurigaster. Among all the substitutions in outgroup and ingroups, totally 55 transitions and 65 transvertions were detected. The value of transition transvertion is quite different to that of mitochondrial genome. We applied parsimony and NJ methods to reconstruct the phylogenetic relationships of the 7 taxa. They show that D. niveifrons is on the basis of the trees, which suggests that it be less related to the rest; D. albomicans, D. s. neonasuta, D. pallidifrons, Taxon I and Taxon J are more related. We suggested that more related topology of D. s. sulfurigaster and D. s. neonasuta due to the specific evolution of ITS, yet not meaning their real relationships. Sequence variations and phylogeny analysis reveal that the ITS may be not an informative marker to nasuta subgroup. However, secondary structure analysis by using PCFOLD 4.0 reveals that the structure of the ITS is quite conservative; the stem-loop of ITS 3'-end may be an important structure of rDNA splicing.

Ocular pneumoplethysmography in head-injured patients

Severe head injury is frequently associated with multiple trauma. In the comatose patient, endotracheal intubation and ventilator support are often required, if there is associated dyssynchronous spontaneous effort. The latter is managed with therapeutic (drug) paralysis. An elaborate life-support and monitoring system coupled with controlled paralysis limits the mobility of the patient for diagnostic procedures, and a continuing reevaluation of neurological status is difficult. Under these circumstances the ocular pneumoplethysmograph provides a simple rapid noninvasive assessment of ocular blood flow, and this reflects cerebral blood flow and alterations in brain compliance. Alterations in the therapeutic regimen can be based on these observations.

Ocular pneumoplethysmography in carotid-cavernous sinus fistulas

Pulsatile exophthalmos in association with carotid-cavernous sinus fistulas has been well defined anatomically, by angiography. This paper presents the physiological assessment of this entity, as measured with ocular pneumoplethysmography (OPG-Gee). The abnormal arteriovenous communication lowers resistance to arterial flow. This is characterized by a lowered ophthalmic systolic pressure and an increased ocular blood flow. The OPG readily documents the physiological result of therapeutic intervention.

Spontaneous dissection of internal carotid arteries. Spontaneous resolution documented by serial ocular pneumoplethysmography and angiography

Spontaneous dissection of the internal carotid artery can appear on an angiogram as a total occlusion of this vessel. This appearance differs from that typical of atherothrombotic occlusion. In four patients with spontaneous dissections of internal carotid arteries, serial ocular pneumoplethysmography demonstrated spontaneous restoration to functional patency. Repeated angiography confirmed the noninvasive testing in all four patients.