Cartilage Sections Research Articles

Double Triangular Cartilage Excision in Otoplasty Revisited.

Prominent ears negatively impact the psychological and social health of individuals. Despite the availability of different surgical correction methods for this congenital condition, many of these techniques might result in significant risks of complications and the condition often reappears. Herein, we present log-term outcomes of our suture-free method that employs various strategies to reduce these risks and prevent recurrences. We analyzed the results of patients who had a bilateral double triangular cartilage excision otoplasty as an outpatient procedure. This previously described technique is designed to correct prominent ears by precisely removing sections of cartilage to reshape the ear mechanically without the need for sutures through the cartilage. We documented any complications after surgery and gathered feedback from patients over an extended follow-up period. A total of 146 patients (292 ears) met the inclusion criteria. The mean age was 23.2 ± 5.3 years. The mean follow-up period was 22 months. Complications were as follows: 3 ears (1.02%) showed superficial skin tissue necrosis at the front of the ear and 17 ears (5.8%) needed further surgery due to unsatisfactory ear rotation. Additionally, 2.73% experienced wound dehiscence, 0.68% had hematomas, 1.02% had external ear infections that were treated with local and systemic antibiotics, 4.1% developed hypertrophic scars, and 8.2% experienced temporary paresthesias. Patients reported being satisfied with the final outcomes at follow-up. Double triangular cartilage excision otoplasty is a safe procedure with few complications, low recurrence rates, and good patients' satisfaction at long-term follow-up. This sutureless technique should be included as an alternative to the existing surgical techniques and added to the skill set of surgeons. IV.

How malocclusion interferes with tissue inhibitor of metalloproteinase-1 expression and morphology of the articular cartilage of the mandible in female rats

ObjectiveThe purpose of this study was to investigate morphological alterations and tissue inhibitor of metalloproteinase-1 expression in the articular cartilage of the mandible under conditions of experimentally induced malocclusion. DesignTwenty-four 8-week-old female Wistar rats were used and divided into control and experimental groups with two different treatment periods (2 and 4 weeks). Sagittal malocclusions were orthodontically created, causing mesial movement of the first molars and distalization of the third molars unilaterally and on opposite sides of the arches. Sagittal sections of the articular cartilage of the mandible were subjected to hematoxylin and eosin and immunohistochemistry for tissue inhibitor of metalloproteinase-1. Chi-square and MannWhitney U tests were applied. ResultsAnimals treated for 2 and 4 weeks showed morphological alterations in articular cartilage of the mandible. The main findings were thickening of the posterior third, layer derangement, osteoclast activity and osteophyte formation. Among the cellular aspects, the presence of chondrocytes with condensed nuclei and cytoplasm reduction were observed. The enzyme in control animals was observed only in the mature layer. Treated animals showed immunopositive cells in the proliferative and mature layers, and in the 2-week treated group, the posterior third of the cartilage had more immunolabeled cells than control (P=0.0291). ConclusionsThe occlusal disorder caused morphological changes in articular cartilage of the mandible, probably due to the attempt to adapt to the new condition. Tissue inhibitor of metalloproteinase-1 expression may play a role as an initial modulator in the biological events observed in articular cartilage of the mandible.

Evaluation of non-penetrative captive bolt stunning as a method of slaughter for white sturgeon (Acipenser transmontanus)

IntroductionPercussive stunning is a widely used and ethically supported method of stunning fish per welfare standards as part of a one- or two-step slaughter process. In this study, the use of a non-penetrative captive bolt (NPCB) gun was evaluated as an effective one-step method of improving welfare for juvenile and adult farmed white sturgeon (Acipenser transmontanus) at slaughter.MethodsA Jarvis HPS-1 NPCB was operated at pressures of 120, 135, and 145 PSI (827.37, 930.79, and 999.74 kPa, respectively) for juvenile sturgeon (n = 3 sturgeon per operating pressure) and 175, 200, and 225 PSI (1206.58, 1378.95, and 1551.32 kPa, respectively) for adult sturgeon (n = 3 sturgeon per operating pressure). Following a single strike, fish were assessed for jaw relaxation and a somatic response before being exsanguinated and transferred to an ice slurry. An hour after slaughter, fish heads were collected, and a section of cartilage containing the brain was removed and fixed in formalin for histological analysis of brain death. To evaluate fish recovery, juveniles (n = 100) and adult female sturgeon (n = 65) were monitored for two hoursafter a single exposure to 145 and 225 PSI, respectively.ResultsHistology results showed there was an effect between operating pressure and intracranial hemorrhage in juvenile sturgeon (p = 0.024). There was a greater meningeal-to-cerebral hemorrhage at 135 PSI compared to the 120 PSI group (p = 0.020) and a trend towards increased tissue damage from 120 PSI to 145 PSI (p = 0.056). Adults showed no significant difference in meningeal hemorrhage at any operating pressure. When investigating recovery rates, NPCB successfully stunned 100% of juvenile sturgeon at 145 PSI, and 225 PSI stunned 90% of adult sturgeon without recovery.DiscussionThese results demonstrate that the use of an NPCB gun is an improvement in animal welfare compared to repeated strikes, but a single application did not produce histological brain death; further research should be conducted to determine optimal pressures that result in immediate brain death.

Comparison of the Visual Scoring Method and Semi-Automatic Image Analysis for Evaluating Staining Intensity of Human Cartilage Sections

Comparison of the Visual Scoring Method and Semi-Automatic Image Analysis for Evaluating Staining Intensity of Human Cartilage Sections

Metabolic rewiring controlled by c-Fos governs cartilage integrity in osteoarthritis

ObjectivesThe activator protein-1 (AP-1) transcription factor component c-Fos regulates chondrocyte proliferation and differentiation, but its involvement in osteoarthritis (OA) has not been functionally assessed.Methodsc-Fos expression was evaluated by immunohistochemistry on...

Therapeutic Effect of Acupotomy at Sanheyang for Cartilage Collagen Damage in Moderate Knee Osteoarthritis: A Rabbit Model.

Acupotomy based on the meridian-sinew theory of traditional Chinese medicine has benefits in treating knee osteoarthritis (KOA). The current study aims to prove that acupotomy at the sinew points of Sanheyang protect the knee joint and alleviate the progression of moderate KOA by evaluating KOA symptoms, cartilage structure, and analyzing the changes of cytokines in rabbit cartilage. The model used was mono-iodoacetate-induced moderate KOA in the rabbit's right leg. Rabbits were divided into the model group, the acupotomy group, and the control group, with each group receiving two parts of treatment for 2 weeks and 4 weeks. We evaluated pain in the knee joint and range of motion. The articular cartilage sections were stained with Safranin O/Fast Green and Masson. We used immunohistochemistry and real-time PCR to detect the protein and mRNA expressions of collagen prototype II (COL-II), matrix metalloproteinase 13 (MMP13), and integrin-β1 (ITG-β1). Compared with the model group, the acupotomy group had higher body weight, lower pain score, higher range of motion, lower Mankin score, and significantly lower protein and mRNA expression of MMP13. After 4 weeks of treatment, Col-II expression in the acupotomy group was significantly higher than that in the model group and the expression of ITG-β1 in the model group was abnormally increased. Acupotomy at Sanheyang improved the pain symptoms and range of joint motion in rabbits with moderate KOA, and could protect Col-II by regulating MMP13, which may be related to ITG-β1-mediated mechanical force transmission, thus reducing the damage to cartilage structure and delaying the progression of moderate KOA.

Chondrotoxic effects of tranexamic acid and povidone-iodine on the articular cartilage of rabbits.

To evaluate the chondrotoxic effects of intra-articular use of TXA 20 mg/kg and/or 0.35% PVPI on knee joint cartilage in an experimental model of rabbits. Forty-four male New Zealand adult rabbits were randomly assigned to four groups (control, tranexamic acid (TXA), povidone-iodine (PVPI), and PVPI + TXA). The knee joint cartilage was accessed through an arthrotomy and exposed to physiological saline SF 0.9% (control group), TXA, PVPI, and PVPI followed by TXA. Sixty days after surgical procedure, the animals were sacrificed and osteochondral specimens of the distal femur were obtained. Histological sections of cartilage from this area were stained with hematoxylin/eosin and toluidine blue. The following cartilage parameters were evaluated by the Mankin histological/histochemical grading system: structure, cellularity, glycosaminoglycan content in the extracellular matrix, and integrity of the tidemark. The isolated use of PVPI causes statistically significant changes in cartilage cellularity (p-value = 0.005) and decrease glycosaminoglycan content (p = 0.001), whereas the isolated use of TXA decreased significantly the glycosaminoglycan content (p = 0.031). The sequential use of PVPI + TXA causes more pronounced alterations in the structure (p = 0.039) and cellularity (p = 0.002) and decreased content of glycosaminoglycans (p < 0.001) all with statistical significance. Data suggest that intra-articular use of tranexamic acid 20 mg/kg and intraoperative lavage with 0.35% povidone-iodine solution for three min are toxic to the articular cartilage of the knee in an experimental in vivo study in rabbits.

Association of Dipeptidylpeptidase 4 (CD26) With Chondrocyte Senescence and Radiographic Progression in Knee Osteoarthritis.

To evaluate the association of dipeptidylpeptidase 4 (DPP-4; also known as CD26) with cellular senescence of human cartilage and progression of knee osteoarthritis (OA). Articular cartilage sections and chondrocytes were acquired from 35 individuals undergoing total knee replacement for OA to evaluate the following: 1) the association between OA severity and established senescence markers (senescence-associated β-galactosidase activity and p16), which was quantified using immunohistochemistry and flow cytometry (n=19 samples); 2) the coexpression of DPP-4 with established senescence markers, which was assessed using flow cytometry; and 3) expression levels of anabolic and catabolic genes, senescence-related genes, and senescence-associated secretory phenotypes in DPP-4+ and DPP-4- cells, which were isolated using fluorescence-activated cell sorting or magnetic-activated cell sorting (n=16 samples). The concentration of soluble DPP-4 was measured in samples of synovial fluid and samples of plasma from the Prediction of Osteoarthritis Progression cohort and then evaluated for association with the severity of radiographic knee OA at baseline (n=65 samples) and the progression of structural radiographic OA (n=57 samples) over a 3-year period. DPP-4 expression was associated with higher senescence-associated β-galactosidase activity, p16 expression, senescence-related gene and catabolic gene (ADAMTS5, MMP13, IL6, and IL8) expression, higher senescence-associated secretory phenotype secretion, and lower anabolic gene (COL2A1 and ACAN) expression in primary chondrocytes. Synovial fluid DPP-4 concentration was associated with radiographic OA progression (odds ratio 105.32; P=0.015), proteases (synovial fluid matrix metalloproteinase 1 and matrix metalloproteinase 3), aggrecan degradation (synovial fluid sulfated glycosaminoglycan), indicators of activated macrophages (synovial fluid CD14 and CD163), and inflammation (synovial fluid interleukin-6). Our study identifies DPP-4 as a key surface marker in senescent chondrocytes and a predictor of radiographic OA progression.

Characterizing site-specific mechanical properties of knee cartilage with indentation-relaxation maps and machine learning

Knee cartilage experiences site-specific focal lesion and degeneration, which is likely associated with tissue inhomogeneity and nonuniform mechanical stimuli in the joint, for which a complete picture remains to be depicted. The present study aimed to develop a methodology to quantify knee cartilage inhomogeneity using porcine knee specimens. Automated indentation-relaxation and needle probing were performed on fully intact cartilage to obtain data that essentially represent continuous distributions of cartilage properties in the knee. Machine learning was then introduced to approximate the tissue inhomogeneity with several regions via clusters of indentation locations, and finite element modeling was used to obtain poromechanical properties for each region using indentation-relaxation and thickness data. Significant region dependence was established from the full time-dependent mechanical response. Seventeen regions, or clusters, were found to best approximate the site-specific poromechanical properties of articular cartilage for femoral groove, lateral and medial condyles and tibial plateaus, after up to eight clusters were tested for each of the five cartilage sections. The region partitions recommended, and tissue properties acquired would facilitate implementation of tissue inhomogeneity in future applications, e.g., contact modeling of the knee joint. The results obtained from 14 porcine knees revealed interesting region differences, for example, the two condyles have the same effective stiffness when responding to slowly applied mechanical loadings but substantially lower stiffness in the medial condyle when responding to fast loadings. This mechanical behavior may be associated with the fact that medial femoral cartilage is more prone to focal lesions than the lateral one.

OPTIMIZATION OF OSTEOCHONDRAL ALLOGRAFT PREPARATION FOR TRANSPLANTATION USING FINITE ELEMENT MODELLING

Many factors have been reported to affect the functional survival of OCA transplants, including chondrocyte viability at time of transplantation, rate and extent of allograft bone integration, transplantation techniques, and postoperative rehabilitation protocols and adherence. The objective of this study was to determine the optimal subchondral bone drilling technique by evaluating the effects of hole diameter on the material properties of OCAs while also considering total surface area for potential biologic benefits for cell and vascular ingrowth.Using allograft tissues that would be otherwise discarded in combination with deidentified diagnostic imaging (MRI and CT), a model of a large shell osteochondral allograft was recreated using LS-PrePost and FEBio based on clinically relevant elastic material properties for cortical bone, trabecular bone, cartilage, and hole ingrowth tissue. The 0.8 mesh size model consisted of 4 mm trabecular bone, 4 mm cortical bone, and 3 mm cartilage sections that summed to a cross-sectional area of 1600 mm2 (40 mm x 40 mm). Holes were modeled to be 4mm deep in relation to clinical practice where holes are drilled from the deep margin of subchondral trabecular bone to the cortical subchondral bone plate. To test the biomechanic variations between drill hole sizes, models with hole sizes pertinent to standard-of-care commercially available orthopaedic drill sizes of 1.1mm, 2.4 mm, or 4.0 mm holes were loaded across the top surface over a one second duration and evaluated for effective stress, effective strain, 1st principal strain, and 3rd principal strain in compressive conditions.Results measured effective stress and strain and 1st and 3rd principal strain increased with hole depth.The results of the present FEA modeling study indicate that the larger 4.0 mm diameter holes were associated with greater stresses and strains within OCA shell graft, which may render the allograft at higher risk for mechanical failure. Based on these initial results, the smaller diameter 2.4 mm and 1.1 mm holes will be further investigated to determine optimal number, configuration, and depth of subchondral drilling for OCA preparation for transplantation

A bioscaffold of decellularized whole osteochondral sheet improves proliferation and differentiation of loaded mesenchymal stem cells in a rabbit model.

As a Natural decellularized extracellular matrix, osteochondral tissue is the best scaffold for the restoration of osteoarthritis defects. Bioscaffolds have the most similarly innate properties like biomechanical properties and the preserved connection of the bone-to-cartilage border. Although, their compacity and low porosity particularly, are proven to be difficulties of decellularization and cell penetration. This study aims to develop a new bioscaffold of decellularized osteochondral tissue (DOT) that is recellularized by bone marrow-derived mesenchymal stem cells (BM-MSCs), as a biphasic allograft, which preserved the interface between the cartilage section and subchondral bone of the joint. Whole osteochondral tissues of rabbit knee joints were sheeted in cartilaginous parts in 200-250µm sections while connected to the subchondral bone and then fully decellularized. The BM-MSCs were seeded on the scaffolds in vitro; some constructs were subcutaneously implanted into the back of the rabbit. The cell penetration, differentiation to bone and cartilage, viability, and cell proliferation in vitro and in vivo were evaluated by qPCR, histological staining, MTT assay, and immunohistochemistry. DNA content analysis and SEM assessments confirmed the decellularization of the bioscaffold. Then, histological and SEM evaluations indicated that the cells could successfully penetrate the bone and cartilage lacunas in implanted grafts. MTT assay confirmed cell proliferation. Prominently, gene expression analysis showed that seeded cells differentiated into osteoblasts and chondrocytes in both bone and cartilage sections. More importantly, seeded cells on the bioscaffold started ECM secretion. Our results indicate that cartilage-to-bone border integrity was largely preserved. Additionally, ECM-sheeted DOT could be employed as a useful scaffold for promoting the regeneration of osteochondral defects.

DIAGNÓSTICO E TREINAMENTO POR TECNOLOGIA DE IMAGEM EM TRAUMATISMOS DO JOELHO NO BASQUETEBOL

ABSTRACT Introduction: The research and development of new methods of injury diagnosis and rehabilitation training in benefits to the health and training of athletes is a contemporary priority. Among modern techniques, diagnostic imaging technology stands out. Objective: Study the auxiliary effect of imaging technology in the diagnosis and rehabilitation training of functional knee joint injuries in basketball practice. Methods: 50 basketball players diagnosed and treated in the past four years for knee joint function injuries in a special hospital were selected, including 28 male and 22 female athletes, aged 17 to 25 years. PerkinElmer Spotlight-300 FTIR spectral imaging system was used to scan the articular cartilage sections, visible light and total absorption images of the samples were obtained by reflection mode imaging. Results: The peak infrared feature of the articular cartilage measured by the infrared spectrum imaging technology is very consistent with the FTIR spectrum. After rehabilitation training, the Y test score of female patients increased from 96.72 ± 6.05 to 105.40 ± 4.23, and the Y test score of male patients increased from 98.34 ± 5.33 to 105.51 ± 4.89, showing significant differences. Conclusion: Infrared spectrum imaging technology is an effective technique for identifying functional knee joint injury, and is of great use for diagnosis and training update in basketball players with knee trauma. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

Study on transport of small molecule rhodamine B within different layers of cartilage

The small molecule nutrients and cell growth factors required for the normal metabolism of chondrocyte mainly transport into the cartilage through free diffusion. However, the specific mass transfer law in the cartilage remains to be studied. In this study, using small molecule rhodamine B as tracer, the mass transfer models of cartilage were built under different pathways including surface pathway, lateral pathway and composite pathway. Sections of cartilage at different mass transfer times were observed by using laser confocal microscopy and the transport law of small molecules within different layers of cartilage was studied. The results showed that rhodamine B diffused into the whole cartilage layer through surface pathway within 2 h. The fluorescence intensity in the whole cartilage layer increased with the increase of mass transfer time. Compared to mass transfer of 2 h, the mean fluorescence intensity in the superficial, middle, and deep layers of cartilage increased by 1.83, 1.95, and 3.64 times, respectively, after 24 h of mass transfer. Under lateral path condition, rhodamine B was transported along the cartilage width, and the molecular transport distance increased with increasing mass transfer time. It is noted that rhodamine B could be transported to 2 mm away from cartilage side after 24 h of mass transfer. The effect of mass transfer under the composite path was better than those under the surface path and the lateral path, and especially the mass transfer in the deep layer of cartilage was improved. This study may provide a reference for the treatment and repair of cartilage injury.

MODIFIED MASSON'S METHOD OF STAINING TISSUES- AN EXPERIMENTAL MICROANATOMY STUDY

Staining of the the tissues is an art which gives fruitful results over a period of time. Many researchers have used various stains, some are costly and some are economical. Special stains like Mallory's trichrome and Massson's trichrome are routinely used for staining various tissues. As few ingredients of Masson's Trichrome were not available, we replaced certain ingredients which were not available by readily available ingredients on an experimental basis and a study was carried out. We used Ponceau S instead of Ponceau 2R and Ehrlich's Haematoxylin instead of Weigert's Iron Haematoxylin for staining parafn sections of tongue, pituitary gland, colon, adrenal gland and hyaline cartilage. Tissues were collected from the cadavers allotted for rst year MBBS students for dissection at Dr B R Ambedkar medical college, Bangalore. After processing the tissues, parafn embedded blocks were prepared and the sections were taken and later washed in tap water followed by staining with special stains with certain ingredients replaced due to non availability. After that, sections were washed by water, dehydrated in graded alcohol, cleared in xylene and mounted in DPX and the Photographs of the slides were taken through the microscope by focusing both under low power and high power. In routine Masson's Trichrome stain, Ponceau S was used instead of Ponceau 2R because of it's non-availability. Further the cost of Ponceau S is very much lesser than Ponceau 2R. Also Ehrlich's Haematoxylin was used instead of Weigert's Iron Haematoxylin. We obsereved that various components like nuclei, cytoplasm, muscle, acidophil and basophil granules, collagen, cartilage, mucin were all well differentiated. On an experimental basis, we replaced the components Ponceau 2R by Ponceau S and Weigert's Iron Haematoxylin by Erhlich's Haematoxylin in Masson's Trichrome method of staining and various tissues were stained with good results.

T2 mapping of cartilage in the equine distal interphalangeal joint with corresponding histology using 0.27 T and 3.0 T magnetic resonance imaging.

Low-field magnetic resonance imaging (MRI) is widely available to equine veterinarians yet is insensitive at detecting cartilage damage in the distal interphalangeal joint (DIPJ). T2 mapping is a quantitative imaging technique that can detect cartilage damage before morphological change is apparent. Validation of a T2 mapping sequence on a low-field MR system. Correlation of the mean T2 relaxation time in sections of cartilage with varying levels of pathology using low- and high-field MRI. Cross-sectional study. Eight phantoms with known (nominal) T2 values underwent low-field (0.27 T) MRI and 38 ex vivo DIPJs were imaged. A further 9 ex vivo DIPJs were imaged on both the low- and high-field MR systems. Immediately after imaging, the DIPJs were disarticulated and samples collected for histology. Histological sections were graded using the Osteoarthritis Research Society International (OARSI) scoring system. Fiji ImageJ software with the MRIAnalysisPak plugin was used to calculate T2 maps and draw the regions of interest (ROIs). There was close agreement between the nominal and the measured T2 values in the phantom study. Spearman's rank correlation demonstrated significant positive correlation between low- and high-field T2 measurements, rho 0.644 (p < 0.001). The intrarater agreement for T2 measurements was excellent, intraclass correlation coefficient (ICC)=0.99 (95% confidence interval [CI]=0.99-1.00), the inter-rater agreement was excellent, ICC=0.88 (95% CI=0.82-0.92) and there was good intrarater agreement for OARSI scores (к=0.76). Only a small number of histological samples were analysed. Both articular cartilage surfaces were measured within the ROI. There were no OARSI grade 0 control samples. A T2 mapping sequence on a low-field 0.27 T MR system was validated. There was a positive correlation between low- and high-field T2 measurements. The findings suggest a higher mean T2 relaxation time in pathological cartilage tissue examined in this study compared to normal equine cartilage tissue.

High-dose Tiger-Gian formula protects the knee joint from surgically induced osteoarthritis in rats.

Although the Tiger-Gian formula (TGF) has proven clinically effective at improving the symptoms of knee osteoarthritis (KOA), the pharmacological effects and underlying mechanisms of TGF have not been examined in any animal model. This study assessed the effects of TGF in male Sprague-Dawley rats with anterior cruciate ligament transection (ACLT) -induced KOA. Thirty rats underwent ACLT surgery and were assigned to either the control group, ACLT alone, ACLT + low-dose TGF (1000 mg/kg), ACLT + high-dose TGF (3000 mg/kg), or ACLT + celecoxib (30 mg/kg). All rats were subjected to micro-computed tomography (micro-CT), weight-bearing behavioral testing, and histological inspections of the knee joint for evidence of structural changes in articular bone, cartilage and synovium. After 6 weeks, force discrepancies in weight-bearing distribution between the normal hind and postoperative limbs revealed superiority with high-dose TGF (18.00 ± 5.93 g) and celecoxib (18.68 ± 5.29 g) versus both ACLT alone (41.29 ± 7.06 g) and low-dose TGF (37.00 ± 7.40 g). Micro-CT images revealed that high-dose TGF and celecoxib similarly improved subchondral bone architecture, protected articular cartilage after ACLT, and downregulated proinflammatory cytokines interleukin-1β and tumor necrosis factor-α in the cartilage and synovial sections. High-dose TGF induced the smallest amount of KOA-associated bone loss. Anti-inflammatory, anti-oxidative, and immunomodulatory effects of TGF were accompanied by reductions in proinflammatory cytokines and improvements in pain and function. TGF-induced anti-osteoporotic activity and inhibition of cartilage degradation were reflected by micro-CT and histological analysis. The findings help to explain how TGF alleviates symptoms of KOA.

The visualization of the mineral and protein distribution in the same histological sections of rat calcified growth plate cartilage

ObjectiveTo determine whether the combination of scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDX) and immunostaining would visualize the mineral and protein distribution in the same histological sections. MethodsParaffin sections of fixed rat hindlimbs were processed for SEM-EDX and subsequently for immunofluorescence staining. ResultsThe localization of calcium, phosphorus, and carbon with type II collagen could be visualized in the same region of calcified growth plate cartilage on the same section. ConclusionsThe combination of SEM-EDX and immunostaining is effective for visualizing mineral and protein distribution in the same histological sections.

Comparison of the effects of autologous and allogeneic purified platelet-rich plasma on cartilage damage in a rabbit model of knee osteoarthritis.

BackgroundPurified platelet-rich plasma (P-PRP) is gradually being used in the treatment of osteoarthritis (OA), and its sources are mainly divided into autologous and allogeneic blood. However, it is unclear whether autologous PRP is more effective or allogeneic PRP is superior.ObjectiveIn this study, autologous and allogeneic P-PRP was injected at early stage of KOA in rabbits, and then the differences in the efficacy of the two P-PRPs against KOA were compared from several perspectives, including pathological histology and immunohistochemistry.MethodExperimental rabbits were divided into normal group (n = 8), model group (n = 8), autologous P-PRP group (n = 8), and allogeneic P-PRP group (n = 8) using a random number table method. The normal and model groups did not receive any treatment, and the autologous P-PRP and allogeneic P-PRP groups received intra-articular injections of autologous and allogeneic P-PRP, respectively, to observe the changes in the gross specimens of the knee joints of the experimental rabbits in each group. The histopathological changes of chondrocytes were also observed by HE-stained sections of articular cartilage, and the expression of chondrocytes Bone morphogenetic protein-2 (BMP-2) and Sox9 were detected by immunohistochemistry.ResultsCompared with the allogeneic P-PRP group, the differences were statistically significant (P < 0.05) in the gross specimens and pathological histological findings in the autologous PRP group. Immunohistochemical results showed that the expression of BMP-2 and Sox9 was elevated in both the autologous P-PRP group and the allogeneic P-PRP group compared with the model group, and the expression of BMP-2 was higher in the autologous P-PRP group than in the allogeneic P-PRP group, with a statistically significant difference (P < 0.05), while there was no difference in the expression of Sox9 between the two groups (P > 0.05).ConclusionIntra-articular injection of autologous P-PRP activated the expression of BMP-2 and Sox9 in chondrocytes and effectively improved KOA cartilage repair and reduced bone redundancy and joint fluid formation, and its efficacy was superior to that of intra-articular injection of allogeneic P-PRP.

Conchal Excision Techniques in Otoplasty: A Literature Review

Background:Prominent ears are a common congenital deformity of the head and neck. Correcting concha hypertrophy is an important step in otoplasty. Despite the risk of postoperative deformity due to the sharp edges created by excision, removing a section of cartilage is sometimes the only method to obtain a satisfying and long-lasting result. Multiple conchal excision techniques have been reported in the literature, with significant differences in approach, outcome evaluation, and complication classification. The objective was to review cartilage excision-based otoplasty procedures to offer plastic surgeons’ insights into current data on outcomes and complications of conchal excision techniques.Methods:We conducted a literature search through the MEDLINE, EMBASE, Scopus, and Cochrane databases. Prospective and retrospective studies on otoplasty, including revision surgeries and conchal excision techniques involving concha cartilage resection, were included. Articles with no outcomes data, review articles, case reports, expert opinion or comment, and nonclinical studies were excluded.Results:There were a total of four manuscripts that fulfilled our criteria. Three out of four authors preferred posterior access that separates the skin excision from the cartilage excision. Following resection, cartilage edges can be approximated by placing cartilage sutures, or they can be allowed to collapse spontaneously. Although only two authors employed a systematic classification for complications, all the articles reviewed indicated a low complication rate and excellent postoperative cosmetic outcomes.Conclusion:Although the techniques and principles stated in the literature varied to some extent, the outcomes of all studies reviewed were comparable.

Mitochonic Acid-5 Inhibits Reactive Oxygen Species Production and Improves Human Chondrocyte Survival by Upregulating SIRT3-Mediated, Parkin-dependent Mitophagy.

Mitochondrial dysfunction is related to the pathogenesis of osteoarthritis (OA); however, there are no effective drugs to treat OA for maintaining mitochondrial homeostasis. Studies have shown that mitochonic acid-5 (MA-5) has a protective effect against mitochondrial damage and plays a role in mitophagy. However, it is not clear whether MA-5 has a beneficial effect on inflammatory articular cartilage. Here, human OA cartilage was obtained from patients undergoing total joint replacement. Interleukin-1β (IL-1β) was used to stimulate chondrocytes and induce inflammatory injury. Cell Counting Kit-8, TUNEL, and flow cytometry assays were used to assess apoptosis. Gene expression was examined using quantitative reverse transcription-polymerase chain reaction. Mitochondrial function was evaluated using immunoblotting, mitochondrial membrane potential assay, JC-1 staining, and immunofluorescence analysis. Mitophagy was detected using immunoblotting and immunofluorescence. 3-(1H-1,2,3-triazol-4-yl) pyridine (3-TYP), a specific inhibitor of Sirtuin 3 (SIRT3), was used to block the SIRT3/Parkin pathway. Mitophagy in the cartilage sections was evaluated via immunohistochemistry. IL-1β was found to induce chondrocyte apoptosis by inhibiting SIRT3 expression and mitophagy. In addition, inflammatory damage reduced the mitochondrial membrane potential and promoted the production of intracellular reactive oxygen species (ROS), leading to increased mitochondrial division, mitochondrial fusion inhibition, and the consequent mitochondrial damage. In contrast, the MA-5 treatment inhibited excessive ROS production by upregulating mitophagy, maintaining the mitochondrial membrane potential, and reducing mitochondrial apoptosis. After chemically blocking SIRT3 with 3-TYP, Parkin-related mitophagy was also inhibited, an effect that was prevented by pretreatment of the chondrocytes with MA-5, thereby suggesting that SIRT3 is upstream of Parkin. Overall, MA-5 was found to enhance the activity of SIRT3, promote Parkin-dependent mitophagy, eliminate depolarized/damaged mitochondria in chondrocytes, and protect cartilage cells. In conclusion, MA-5 inhibits IL-1β-induced oxidative stress and protects chondrocytes by upregulating the SIRT3/Parkin-related autophagy signaling pathway.