Achieving Zero-Temperature Coefficient Point Behavior by Defect Passivation for Temperature-Immune Organic Field-Effect Transistors.

Organic field-effect transistors (OFETs) have broad prospects in biomedical, sensor, and aerospace applications. However, obtaining temperature-immune OFETs is difficult because the electrical properties of organic semiconductors (OSCs) are temperature-sensitive. The zero-temperature coefficient (ZTC) point behavior can be used to achieve a temperature-immune output current; however, it is difficult to achieve in organic devices with thermal activation characteristics, according to the existing ZTC point theory. Here, the Fermi pinning in OSCs is eliminated using the defect passivation strategy, making the Fermi level closer to the tail state at low temperatures; thus threshold voltage (VT) is negatively correlated with temperature. ZTC point behaviors in OFETs are achieved by compensation between VT and mobility at different temperatures to improve its temperature immunity. A temperature-immune output current can be realized in a variable-temperature bias voltage test over 50000 s by biasing the device at the ZTC point. This study provides an effective solution for temperature-immune OFETs and inspiration for their practical application.

The effects of tourniquet use on blood loss and perioperative complications in total knee arthroplasty.

BACKGROUND: There has been ongoing debate about the use of tourniquets in total knee arthroplasty, and their application is widely studied. A comprehensive understanding of the advantages and disadvantages of tourniquet use during the procedure is crucial for optimizing surgical outcomes. This study aimed to investigate the effectiveness of tourniquet application, with a particular focus on blood loss and perioperative complications, providing valuable insights for clinical practice. METHODS: Fifty patients who underwent total knee arthroplasty were randomized into tourniquet (n = 25) and nontourniquet (n = 25) groups. The same surgeon performed all surgical procedures. The follow-up time was 14 days after surgery. Primary outcomes were hemoglobin level changes, blood loss, operation time, and perioperative plasma D-dimer levels. Secondary outcomes were postoperative complications, including thrombotic and nonthrombotic events. RESULTS: No significant differences were found in drainage, calculated blood loss, total blood loss, postoperative hemoglobin levels, or blood transfusion between the two groups (P > 0.05). No differences in D-dimer levels were observed on postoperative Days 1, 3, and 14 between the two groups, except on postoperative Day 7, when the D-dimer level in the tourniquet group was lower than that in the nontourniquet group (P = 0.03). The incidence of local complications (thigh bruising, blisters, pain, fat liquefaction, and superficial infections) in the tourniquet group was significantly higher than that in the nontourniquet group (P = 0.03), but no significant differences were found in thromboembolic and nonthromboembolic events or overall complications (P > 0.05). CONCLUSION: We conclude that tourniquet use does not reduce the length of surgery or blood loss but does increase local complications in total knee arthroplasty.

Oxygen-Induced Barrier Lowering for High-Performance Organic Field-Effect Transistors.

Organic field-effect transistors (OFETs) have the advantages of low-cost, large-area processing and could be utilized in a variety of emerging applications. However, the generally large contact resistance (Rc) limits the integration and miniaturization of OFETs. The Rc is difficult to reduce due to an incompatibility between obtaining strong orbit coupling and the barrier height reduction. In this study, we developed an oxygen-induced barrier lowering strategy by introducing oxygen (O2) into the nanointerface between the electrodes and organic semiconductors layer and achieved an ultralow channel width-normalized Rc (Rc·W) of 89.8 Ω·cm and a high mobility of 11.32 cm2 V-1 s-1. This work demonstrates that O2 adsorbed at the nanointerface of metal-semiconductor contact can significantly reduce the Rc from both experiments and theoretical simulations and provides guidance for the construction of high-performance OFETs, which is conducive to the integration and miniaturization of OFETs.

Analysis of risk factors for advanced age in patients with frozen shoulder.

OBJECTIVE: To explore the risk factors of elderly patients with frozen shoulder. METHODS: 262 cases of scapulohumeral periarthritis treated in our hospital from January 2020 to December 2020 were analyzed retrospectively. According to the age of patients, patients younger than 60 years old were divided into middle-aged group (101 cases), patients between 60 and 75 years old were divided into old-aged group (91 cases), and patients ≥ 75 years old were divided into old-aged group (70 cases). The general demographic data and clinical data of the three groups were compared. Visual analogue scale (VAS) was used to evaluate the degree of pain. Finally, the dependent variable is set as whether the onset age of scapulohumeral periarthritis patients is advanced. Univariate and multivariate Logistic regression was used to analyze the risk factors of frozen shoulder patients at an advanced age. RESULTS: There were no significant differences in general demographic data, fixed position, hypertension history, smoking history, drinking history, supraspinatus muscular atrophy and physical exercise among the three groups (all P > 0.05). The course of disease, diabetes, surgical treatment, pain degree, operation time, cholecystitis, coronary heart disease, pain degree three months after operation and cervical spondylosis in the elderly group were all higher than those in the middle-aged group and the elderly group, and the differences were statistically significant (all P < 0.05). The course of scapulohumeral periarthritis, the degree of pain and the degree of pain 3 months after operation in the elderly group were higher than those in the middle-aged group, with significant differences (all P < 0.05). Univariate Logistic regression analysis showed that the risk factors of scapulohumeral periarthritis in the elderly included diabetes mellitus (OR = 3.067, 95% CI 1.881-4.587, P < 0.001), operative treatment (OR = 3.076, 95% CI 1.365-6.765, P = 0.006), VAS score (OR = 2.267, 95% CI 1.117-3.887, P = 0.013), operation time (OR = 1.537, 95% CI 1.305-2.579, P < 0.001), cholecystitis (OR = 2.143, 95% CI 1.019-4.876, P = 0.023), coronary heart disease(OR = 3.128, 95% CI 1.428-7.019, P = 0.005), VAS at 3 months after operation (OR = 1.537, 95% CI 0.786-2.635, P = 0.002), and cervical spondylosis(OR = 1.162, 95% CI 1.029-1.321, P = 0.012). Multivariate logistic regression analysis showed that the risk factors for the onset of the disease at advanced age included fatty infiltration (OR = 4.021, 95% CI 2.981-9.682, P < 0.001), surgical treatment (OR = 4.109, 95% CI 1.419-7.832, P = 0.008), VAS score (OR = 3.081, 95% CI 1.042-7.931, P = 0.046) and operation time (OR = 1.537, 95% CI 1.305-2.579, P < 0.001). CONCLUSION: Risk factors of frozen shoulder at advanced age include fat infiltration, surgical treatment, VAS score and surgical time. In clinical practice, we should refer to the above indicators to help patients with early medical intervention and prevent their onset.

Midterm outcomes of 18 patients with primary intra-articular diffuse tenosynovial giant cell tumor (TGCT) of the knee treated with complete arthroscopic synovectomy and postoperative low-dose radiotherapy at a mean follow-up of 68 months.

OBJECTIVE: To evaluate the long-term clinical outcome of the treatment of complete arthroscopic synovectomy combined with low-dose external radiotherapy in the knee affected by primary intra-articular diffuse tenosynovial giant cell tumor (TGCT). METHODS: From May 2009 to January 2016, 18 patients with intra-articular diffuse TGCT underwent complete arthroscopic synovectomy and low-dose external-beam radiotherapy in Zhongnan Hospital were enrolled in this retrospective study. The preoperative symptoms of patients, the complications during or after the arthroscopic procedure and the recurrence were collected and recorded. Each patient was evaluated before treatment and at the follow-up visit. Efficacy evaluation criteria were based on Ogilvie-Harris score, and the evaluation of the functional ability of knee was based on the International Knee Documentation Committee (IKDC) Score. RESULTS: The mean time from symptom onset to surgery was 9.1 ± 5.8 months (range from 3 to 29 months). The most frequent preoperative symptoms were joint effusion (100%), diffuse non-specific knee pain (66.7%), and a decreased range of motion (83.3%). Mean follow-up time was 68.0 ± 18.1 months (range from 35 to 120 months). The mean evaluation score according to the Ogilvie-Harris criteria before treatment was 3.19 ± 0.74, which corresponded to a rating of "poor". The mean score after treatment was 8.79 ± 1.57, rated as "good". The Ogilvie-Harris score was significantly increased after treatment (P = 0.003). The IKDC score of all patients increased significantly from 37.1 ± 3.8 before treatment to 83.9 ± 11.3 after treatment. The IKDC score was obviously increased after treatment (P = 0.001). No recurrence was noted at final follow-up. There were no complications during or after the arthroscopic procedure. CONCLUSION: The outcome of this study proved that complete arthroscopic synovectomy combined with low-dose external radiotherapy was appropriate for treating primary intra-articular diffuse TGCT of the knee joint. It could be safely and reliably used with minimal complications, fast postoperative recovery and satisfactory control of recurrence rates.

Prenatal smoke (Nicotine) exposure and offspring's metabolic disease susceptibility in adulthood.

Exposure to smoking (nicotine) during pregnancy not only directly affects fetal development, but also increases susceptibility to metabolic diseases in adulthood, but the mechanism of action remains unclear. Here, we review epidemiological and laboratory studies linking these relationships. In addition to the direct effect of nicotine on the fetus, intrauterine neuroendocrine-metabolic programming mediated by maternal glucocorticoid overexposure also plays an important role, involving glucocorticoid-insulin-like growth factor 1 (GC-IGF1) axis, hypothalamic-pituitary-adrenal (HPA) axis, renin-angiotensin system (RAS) and other endocrine systems. Epigenetics is involved in intrauterine neuroendocrine-metabolic programming, metabolic disease susceptibility and multigenerational inheritance. There are "two programming" and "two strikes" mechanisms for the occurrence of fetal-originated metabolic diseases in adulthood. These innovative research summaries and academic viewpoints provide experimental and theoretical basis for systematically elucidating the occurrence and development of fetal-originated metabolic diseases.

Low miR-92a-3p in oocytes mediates the multigenerational and transgenerational inheritance of poor cartilage quality in rat induced by prenatal dexamethasone exposure.

An adverse environment during pregnancy leads to intrauterine programming changes in multiple generations, resulting in the multigenerational inheritance of abnormal phenotype. Here, we reported the multigenerational inheritance of poor articular cartilage quality induced by prenatal dexamethasone exposure (PDE) with 0.2 mg/kg·d dexamethasone from gestational day (GD) 9 to GD20 in Wistar rats and investigated its intrauterine epigenetic programming mechanism. For the F1 female offspring at GD20, we found that the matrix synthesis of cartilage was suppressed, the histone 3 lysine 9 acetylation (H3K9ac) level and mRNA expression of the TGFß signaling pathway were decreased, and the expression of histone deacetylase (HDAC) 2 was increased in the cartilage. Meaningfully, the similar changes were also found in the F1-F3 female adult offspring. Furthermore, PDE decreased the expression of miR-92a-3p in the oocytes of the F1-F2 offspring and in the cartilage of the F1-F3 generations. In vitro, the effect of dexamethasone on chondrocytes revealed that it inhibited the expression of miR-92a-3p through activating and binding glucocorticoid receptor, and reduced the H3K9ac level in the promoter of the TGFß signaling pathway through the increased HDAC2. In conclusion, PDE induces the multigenerational inheritance of poor articular cartilage quality in female adult offspring; the potential mechanism involves the intergenerational effect of low miR-92a-3p expression in oocytes and low functional programming of TGFß signaling pathway induced by decreased H3K9ac level via upregulating HDAC2. This study provides a new perspective to explain the multi-generation inheritance of PDE-induced organ dysplasia in adult offspring.

Autologous Dedifferentiated Osteogenic Bone Marrow Mesenchymal Stem Cells Promote Bone Formation in a Rabbit Model of Anterior Cruciate Ligament Reconstruction versus Bone Marrow Mesenchymal Stem Cells.

PURPOSE: This study aimed to verify whether transplantation of dedifferentiated osteogenic bone marrow mesenchymal stem cells (De-BMSCs) at the tendon-bone interface could result in more bone formation than BMSC transplantation in anterior cruciate ligament (ACL) reconstruction. METHODS: BMSCs from femur and tibia of New Zealand White rabbit were subjected to osteogenic induction and then cultured in osteogenic factor-free medium; the obtained cell population was termed De-BMSCs. Bilateral ACL reconstruction was performed in 48 adult rabbits. Three groups were established: control group with alginate gel injection, BMSCs group with the BMSCs injection, and De-BMSCs group with the De-BMSCs injection. At week 4 and 12 postoperatively, tendon-bone healing by histologic staining, micro-computed tomography examination, and biomechanical test were evaluated. RESULTS: The expression of α1 chain of type I collagen, osteocalcin, and osteopontin at the tendon-bone interface in the De-BMSCs group was greater than in the control or BMSCs group. The bone volume/total volume by micro-computed tomography scan was significantly greater in the De-BMSCs group than that in the control group (P = .013) or BMSCs group (P = .045) at 4 weeks, and greater than that in the control group (P = .014) or BMSCs group (P = .017) at 12 weeks. The tunnel area was significantly smaller in the De-BMSCs group than in the control group (P = .013) or BMSCs group (P = .044) at 12 weeks. The failure load and stiffness in De-BMSCs group were both significantly enhanced at 4 and 12 weeks than control group or De-BMSCs group. CONCLUSIONS: De-BMSCs transplantation can promote bone formation at the tendon-bone interface better than BMSCs transplantation in ACL reconstruction and increase the early biomechanical strength of the reconstructed ACL CLINICAL RELEVANCE: De-BMSCs transplantation is a potential choice for enhancing early bone formation in the tunnel in ACL reconstruction.

Nanog/NFATc1/Osterix signaling pathway-mediated promotion of bone formation at the tendon-bone interface after ACL reconstruction with De-BMSCs transplantation.

BACKGROUND: Bone formation plays an important role in early tendon-bone healing after anterior cruciate ligament reconstruction (ACLR). Dedifferentiated osteogenic bone marrow mesenchymal stem cells (De-BMSCs) have enhanced osteogenic potential. This study aimed to investigate the effect of De-BMSCs transplantation on the promotion of bone formation at the tendon-bone interface after ACLR and to further explore the molecular mechanism of the enhanced osteogenic potential of De-BMSCs. METHODS: BMSCs from the femurs and tibias of New Zealand white rabbits were subjected to osteogenic induction and then cultured in medium without osteogenic factors; the obtained cell population was termed De-BMSCs. De-BMSCs were induced to undergo osteo-, chondro- and adipo-differentiation in vitro to examine the characteristics of primitive stem cells. An ACLR model with a semitendinosus tendon was established in rabbits, and the animals were divided into a control group, BMSCs group, and De-BMSCs group. At 12 weeks after surgery, the rabbits in each group were sacrificed to evaluate tendon-bone healing by histologic staining, micro-computed tomography (micro-CT) examination, and biomechanical testing. During osteogenic differentiation of De-BMSCs, an siRNA targeting nuclear factor of activated T-cells 1 (NFATc1) was used to verify the molecular mechanism of the enhanced osteogenic potential of De-BMSCs. RESULTS: De-BMSCs exhibited some properties similar to BMSCs, including multiple differentiation potential and cell surface markers. Bone formation at the tendon-bone interface in the De-BMSCs group was significantly increased, and biomechanical strength was significantly improved. During the osteogenic differentiation of De-BMSCs, the expression of Nanog and NFATc1 was synergistically increased, which promoted the interaction of NFATc1 and Osterix, resulting in increased expression of osteoblast marker genes such as COL1A, OCN, and OPN. CONCLUSIONS: De-BMSCs transplantation could promote bone formation at the tendon-bone interface after ACLR and improve the biomechanical strength of the reconstruction. The Nanog/NFATc1/Osterix signaling pathway mediated the enhanced osteogenic differentiation efficiency of De-BMSCs.

Safety and Effectiveness of Orthopaedic Medical Staff in Providing Support in Combating the COVID-19 Pandemic: A Retrospective Investigation from Wuhan, China.

OBJECTIVE: To evaluate whether it is safe and effective for orthopaedic medical staff to provide support to the work against COVID-19. METHODS: One hundred and twenty-two orthopaedic medical staff from the orthopaedic center of Zhongnan Hospital of Wuhan University were included in this retrospective investigation. A total of 43 surgeons and 69 nurses provided medical support in the treatment of COVID-19 patients from 1 January 2020 to 8 April 2020 in four different hospitals in Wuhan. We collected data on the age, gender, and body temperature of orthopaedic medical staff, as well as the results for their chest CT scans, SARS-CoV-2 RNA, SARS-CoV-2 IgM and SARS-CoV-2 IgG tests, and training and examinations on COVID-19 knowledge. We also collected data on the time span of work, the number of infected staff during the support period, the number of COVID-19 patients the surgeons treated and the cure rate, the performance of the surgeons as assessed by the specialists and patients, and the number of infected staff during the pandemic. RESULTS: Among the 49 surgeons and 73 nurses, 43 surgeons and 69 nurses provided support against COVID-19. A total of 12 surgeons and 11 nurses provided support in the fields of respiration, intensive care, and emergency. A total of 34 surgeons and 58 nurses worked in the designated wards restructured for COVID-19 in the orthopaedic building. The average time span of work for the surgeons and nurses was 14.78 ± 3.64 days and 24.77 ± 7.58 days, respectively. No staff were infected during the support period. Over 1000 patients were received in the fever clinic by orthopaedic surgeons. The overall number of the treated hospitalized patients was 622. Among these patients, 226 cases were mild, 318 were mild to moderate, and 58 were severe or critical. The cure rate was 96.01%, 99.37%, and 52.00% respectively. The performance of the surgeons was scored 87.02 ± 3.17 and 90.69 ± 3.58 by the specialists and the patients, respectively. During the whole pandemic, 3 surgeons and 3 nurses who did not participate in the support work were infected in the early stages. The morbidity of all the orthopaedic staff was 4.92% during the whole pandemic, while no one was infected during the support work. CONCLUSION: Our investigation indicated that although they worked outside their specialty, it was safe and effective for the orthopaedic staff to provide medical support in the work against COVID-19 with adequate precautions and proper training.

Aspirin attenuates podocyte injury in diabetic rats through overriding cyclooxygenase-2-mediated dysregulation of LDL receptor pathway.

AIM: This study aimed to investigate the effects of aspirin on podocyte injury and its underlying mechanisms in diabetic nephropathy (DN). METHODS: Eight-week-old male Sprague-Dawley rats were divided into three groups: non-diabetic rats (Control), streptozotocin-induced diabetic rats (DM), and diabetic rats treated with aspirin (DM + Aspirin) for 12 weeks. Intracellular lipid accumulation was evaluated by Oil Red O staining and quantitative free cholesterol assays. Podocyte injury and the levels of COX-2, inflammatory cytokines, and low-density lipoprotein receptor (LDLr) pathway-related proteins were evaluated by electron microscopy, immunohistochemical staining, and Western blotting, respectively. RESULTS: Lipid levels and urinary albumin-creatinine ratios were higher in the DM rats than in the Control rats. Periodic acid-Schiff staining showed glomerular hypertrophy and mild mesangial area widening in the DM rats. Electron microscopy showed that the podocyte foot processes were significantly flattened or absent in the DM rats. The protein expression levels of WT-1 and nephrin in the podocytes of DM rats were reduced. Interestingly, lipid accumulation in the kidneys of DM rats was significantly increased due to increased protein expression levels of LDLr, sterol regulatory element-binding protein (SREBP) cleavage-activating protein (SCAP), SREBP-2, cyclooxygenase-2 (COX-2), and inflammatory cytokines. Confocal immunofluorescent staining showed that COX-2 and WT-1 were co-expressed. Furthermore, COX-2 protein expression levels were positively correlated with LDLr protein expression levels. However, when COX-2 expression was inhibited by aspirin, these changes in the DM rats were significantly attenuated. CONCLUSION: Aspirin attenuates podocyte injury in DN, which may be through COX-2-mediated dysregulation of LDLr pathway.

Arthroscopic removal of loose bodies using the accessory portals in the difficult locations of the knee: a case series and technical note.

BACKGROUND: It is often technically demanding to find and remove loose bodies in several difficult locations like the popliteus hiatus and posterior compartment arthroscopically. We aim to present the technical aspects of establishing some special accessory portals to achieve arthroscopic removal of the loose bodies in these locations. METHODS: From September 2010 to July 2017, 76 patients underwent removal of loose bodies in the popliteus hiatus and posterior compartment arthroscopically using some special accessory portal techniques. An auxiliary extreme lateral approach was established to remove loose bodies in the popliteus hiatus; a double-posteromedial portal was applied to handle loose body removal in the posteromedial compartment, and the posterior trans-septal portal was needed for loose body removal in the posterolateral compartment. Functional outcomes were evaluated using Lysholm score, Tegner score, and International Knee Documentation Committee (IKDC) score, respectively. RESULTS: Seventy-six patients (24 males and 52 females, average age 54.9 ± 11.4) finished the follow-up visit at 3 weeks after surgery. There was no statistically significant difference among the three groups in demographics. All the patients were performed following the special technique. According to a comparison of knee joint scores before and after surgery, all the patients obtained good prognosis using some special accessory portals in loose body removal. CONCLUSIONS: With the help of the above accessory portals under endoscopic visualization, loose bodies in the popliteus hiatus and posterior compartment of the knee can be safely and effectively removed.

Lipoprotein(a) accelerated the progression of atherosclerosis in patients with end-stage renal disease.

BACKGROUND: Increased plasma level of lipoprotein(a) (Lpa) is a risk factor of cardiovascular diseases. This study aimed to explore the role of Lpa in the progression of atherosclerosis in patients with end-stage renal disease (ESRD) and to investigate whether its potential mechanism is mediated by CXC chemokine ligand 16 (CXCL16) and low-density lipoprotein receptor (LDLr). METHODS: This is a retrospective clinical study. From January 2015 to April 2016, forty-six ESRD patients from Danyang First People's Hospital were investigated. The patients were grouped according to their plasma Lpa levels: control group (Lpa < 300 mg/l, n = 23) and high Lpa group (Lpa ≥ 300 mg/l, n = 23). ESRD Patients with acute infective diseases, cancer, and/or chronic active hepatitis were excluded. Biochemical indexes and lipid profiles of the patients were measured. Surgically removed tissues from the radial arteries of ESRD patients receiving arteriovenostomy were used for the preliminary evaluation of atherosclerosis. Haematoxylin-eosin (HE) and filipin staining were used to observe foam cell formation. Protein expression levels of Lpa, CXCL16, and LDLr were detected by immunohistochemistry staining and immunofluorescent staining. RESULTS: There was more foam cell formation and cholesterol accumulation in the radial arteries of the high Lpa group than in those of the control group. Furthermore, the expression levels of Lpa, CXCL16, and LDLr were significantly increased in the radial arteries of the high Lpa group. Correlation analyses showed that the protein expression levels of Lpa (r = 0.72, P < 0.01), LDLr (r = 0.54, P < 0.01), and CXCL16 (r = 0.6, P < 0.01) in the radial arteries of ESRD patients were positively correlated with the plasma Lpa levels. Further analyses showed that the co-expression of Lpa with LDLr or CXCL16 was increased in the high Lpa group. CONCLUSIONS: High plasma Lpa levels accelerated the progression of atherosclerosis in ESRD through inducing Lpa accumulation in the arteries, which was associated with LDLr and CXCL16. These two lipoproteins could both be major lipoprotein components that regulate the entry of Lpa into arterial cells.

Clinical manifestation and arthroscopic treatment of symptomatic posterior cruciate ligament cyst.

BACKGROUND: Ganglion cyst of cruciate ligaments is a rare lesion; the prevalence is 0.3-0.8%. The purpose of this study was to present clinical features of symptomatic posterior cruciate ligament (PCL) cyst, introduce the arthroscopic excision technique, and evaluate the clinical outcome. METHODS: A series of 11 patients with symptomatic PCL cyst from November 2012 to December 2014 were involved in this retrospective study. Detailed medical history collecting and physical examination were conducted. Magnetic resonance imaging (MRI) scan was used to confirm the diagnosis. Arthroscopic resection was performed, and the sample of the cyst was taken for pathologic examination. The follow-up averaged 30.7 months. International Knee Documentation Committee (IKDC) score, the range of motion (ROM), and MRI evaluations were obtained pre- and postoperatively to assess the surgical outcome. SPSS software was used for statistics analysis. RESULTS: Eight males and 3 females with 6 left knees and 5 right knees were enrolled, the mean age was 34.4 years, and the duration of symptom was 19.0 months. All cases had a definite history of knee trauma or injury. The most common symptom was knee pain at flexion or in flexion-associated activities. MRI revealed the location and size of the cyst in each case. Pathologic examination showed the cyst wall was composed of dense fibroconnective tissue and widespread thick bundles of collagen, which is similar to the structure of ganglion cyst. At the final follow-up, MRI evaluation showed no cyst recurrence. The preoperative ROM and IKDC score were 2.3° to 108.6° and 40.5 ± 11.3, respectively, compared with the postoperative ROM and IKDC score which were 0° to 134.1° and 85.5 ± 4.8 (p < 0.05) separately. CONCLUSIONS: We conclude that the etiology of symptomatic PCL cyst is most likely associated with trauma, pain on flexion is a typical manifestation of symptomatic PCL cyst, MRI evaluation is an ideal examination for the diagnosis, and arthroscopic resection of symptomatic PCL cysts has a good outcome with no recurrence.

Prenatal nicotine exposure intergenerationally programs imperfect articular cartilage via histone deacetylation through maternal lineage.

Accumulating evidence has shown that the impact of prenatal environmental factors on the organs of the offspring could last until the adulthood. Here, we aimed to investigate these effects and the potential mechanism of prenatal nicotine exposure (PNE) on the female adult cartilage of the first generation (PNE-F1) and the second generation (PNE-F2). Pregnant Wistar rats were injected with 2.0 mg/kg.d nicotine from gestational day (GD) 9 to 20. Then their F1 generation at GD20 and postnatal week (PW) 12, and F2 generation at PW12 were harvested. The expression of extracellular matrix (ECM) and transforming growth factor ß (TGFß) signaling genes were analyzed by real-time quantitative PCR, and the histone acetylation was examined by chromatin immunoprecipitation assay. The results showed that PNE reduced the ECM and TGFß signaling gene expressions in both PNE-F1 and PNE-F2 female adult articular cartilage. In the F1 generation, PNE inhibited the acetylation at H3K9 of TGFß, TGFß receptor 1 (TGFßR1), SRY-type high mobility group box 9 (SOX9), a1 chain of type II collagen (COL2A1) and aggrecan (ACAN) gene promoters at both GD20 and PW12. In PNE-F2 at PW12, the obvious deacetylation at H3K9 of the TGFßR1 and COL2A1 promoters still existed. Moreover, in rat fetal chondrocytes, corticosterone rather than nicotine directly induced the hypoacetylation of H3K9 of TGFßR1 and COL2A1 genes, which might be the main cause of imperfect cartilage for PNE-F2. This study may be helpful to elucidate the developmental variability of articular cartilage quality and useful for the early prevention of articular damage.

Histone hypo-acetylation of Sox9 mediates nicotine-induced weak cartilage repair by suppressing BMSC chondrogenic differentiation.

BACKGROUND: Nicotine has negative effects on tissue repair, little research concerns its effect on the cartilage repair of tissue engineering stem cells. The present study aimed to investigate the effects of nicotine on the bone marrow-derived mesenchymal stem cells' (BMSCs) chondrogenic repair function of cartilage defects and explored the molecular mechanism. METHODS: A cartilage defect model of rat was repaired by BMSC transplantation, and treated with nicotine or saline at 2.0 mg/kg/d in 12 weeks. Nicotine's effect on chondrogenic differentiation was studied by exposing BMSCs to nicotine at 0.1, 1, 10, and 100 µM, and methyllycaconitine (MLA), which is a selective α7-nicotinic acetylcholine receptor (nAChR) inhibitor and si-RNA of nuclear factor of activated T cells 2 (NFATc2), were used to verify the molecular mechanism of nicotine's effect. RESULTS: Data showed that nicotine inhibited cartilage repair function by suppressing SRY-type high-mobility group box 9 (Sox9) in regenerated tissues. Further in vitro study demonstrated that nicotine enhanced intracellular Ca2+ and activity of calcineurin (CaN) through α7-nAChR, increased the nucleic expressions of NFATc2 and the bindings to SOX9 promoter, and thus reduced the acetylation of H3K9 and H3K14 in SOX9 promoter. CONCLUSIONS: Findings from this study demonstrated that nicotine suppressed the chondrogenic differentiation of BMSCs in vivo and in vitro, which offers insight into the risk assessment of cartilage defect repair in a nicotine exposure population and its therapeutic target.

Single-bundle versus double-bundle autologous anterior cruciate ligament reconstruction: a meta-analysis of randomized controlled trials at 5-year minimum follow-up.

BACKGROUND: Both single-bundle (SB) and double-bundle (DB) techniques were widely used in anterior cruciate ligament (ACL) reconstruction recently. Nevertheless, up to now, no consensus has been reached on whether the DB technique was superior to the SB technique. Moreover, follow-up of the included studies in the published meta-analyses is mostly short term. Our study aims to compare the mid- to long-term outcome of SB and DB ACL reconstruction concerning knee stability, clinical function, graft failure rate, and osteoarthritis (OA) changes. METHODS: This study followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The PubMed, Embase, and the Cochrane Library were searched from inception to October 2017. The study included only a randomized controlled trial (RCT) that compared SB and DB ACL reconstruction and that had a minimum of 5-year follow-up. The Cochrane Collaboration's risk of bias tool was used to assess the risk of bias for all included studies. Stata/SE 12.0 was used to perform a meta-analysis of the clinical outcome. RESULTS: Five RCTs were included, with a total of 294 patients: 150 patients and 144 patients in the DB group and the SB group, respectively. Assessing knee stability, there was no statistical difference in side-to-side difference and negative rate of the pivot-shift test. Considering functional outcome, no significant difference was found in proportion with International Knee Documentation Committee (IKDC) grade A, IKDC score, Lysholm scores, and Tegner scores. As for graft failure rate and OA changes, no significant difference was found between the DB group and the SB group. CONCLUSION: The DB technique was not superior to the SB technique in autologous ACL reconstruction regarding knee stability, clinical function, graft failure rate, and OA changes with a mid- to long-term follow-up.

Anteromedial versus transtibial technique in single-bundle autologous hamstring ACL reconstruction: a meta-analysis of prospective randomized controlled trials.

BACKGROUND: The aim of this study was to compare the clinical outcome and postoperative complication between single-bundle anterior cruciate ligament (ACL) reconstruction with an anteromedial (AM) technique and a transtibial (TT) technique. METHODS: The study includes clinical randomized controlled trials comparing the clinical outcomes of ACL reconstruction using the autologous hamstring tendon with an AM method and a TT method published up to September 2017 were retrieved from PubMed, Cochrane Library, and Embase databases. Relevant data were extracted and the Physiotherapy Evidence Database (PEDro) scale was used to assess the methodological quality. Stata/SE 12.0 was used to perform a meta-analysis of the clinical outcome. RESULTS: Five RCTs were included, with a total of 479 patients: 239 patients and 240 patients in the AM group and the TT group, respectively. Assessing postoperative stability, better results were found in the AM group for the negative rate of the Lachman test (P < 0.05), the negative rate of the pivot-shift test (P < 0.05) and the side-to-side difference (P < 0.05). Assessing postoperative functional outcome, the AM group yielded superior results in proportion with International Knee Documentation Committee (IKDC) grade A (P < 0.05) and the Lysholm scores (P < 0.05) but had a comparable IKDC score (P > 0.05). In terms of postoperative complication, no significant difference was found between the AM group and the TT group (P > 0.05). CONCLUSIONS: The outcome of single-bundle ACL reconstruction with the AM technique is better than that with the TT technique in terms of postoperative stability and functional recovery of the knee.

Glucocorticoid mediates prenatal caffeine exposure-induced endochondral ossification retardation and its molecular mechanism in female fetal rats.

Our previous studies discovered that prenatal caffeine exposure (PCE) could induce intrauterine growth retardation (IUGR) and long-bone dysplasia in offspring rats, accompanied by maternal glucocorticoid over-exposure. This study is to explore whether intrauterine high glucocorticoid level can cause endochondral ossification retardation and clarify its molecular mechanism in PCE fetal rats. Pregnant Wistar rats were intragastrically administered 30 and 120 mg/kg day of caffeine during gestational days (GDs) 9-20, then collected fetal serum and femurs at GD20. In vitro, primary chondrocytes were treated with corticosterone (0-1250 nM), caffeine (0-100 µM), mitogen-inducible gene 6 (Mig-6) siRNA and epidermal growth factor receptor (EGFR) siRNA, respectively, or together. Results showed that the hypertrophic chondrocytes zone (HZ) of PCE fetal femur was widened. Meanwhile, the expression levels of chondrocytes terminal differentiation genes in the HZ were decreased, and the chondrocytes apoptosis rate in the HZ was decreased too. Furthermore, PCE upregulated Mig-6 and suppressed EGFR expression in the HZ. In vitro, a high-concentration corticosterone (1250 nM) upregulated Mig-6 expression, inhibit EGFR/c-Jun N-terminal kinase (JNK) signaling pathway and terminal differentiation genes expression in chondrocytes and reduced cell apoptosis, and these above alterations could be partly reversed step-by-step after Mig-6 and EGFR knockdown. However, caffeine concentration dependently increased chondrocyte apoptosis without significant changes in the expression of terminal differentiation genes. Collectively, PCE caused endochondral ossification retardation in the female fetal rats, and its main mechanism was associated with glucocorticoid (rather than caffeine)-mediated chondrocyte terminal differentiation suppression by the upregulation of Mig-6 and then inhibition of EGFR/JNK pathway-mediated chondrocyte apoptosis.