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1.
Medicine (Baltimore) ; 99(3): e18425, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32011435

RESUMO

RATIONALE: Hypophosphatemic rickets (HR) is a rare hereditary disease characterized by hypophosphatemia, defects in bone mineralization, and rickets, and surgical intervention is warranted for the patient of severe skeletal deformity. PATIENT CONCERNS: Here we report a case of an 11-year-old boy who presented with severe varus deformities of the bilateral lower extremities and was associated with uncoordinated gait with multiple unintentional falls onto ground resulting in fractures of lower extremities. DIAGNOSES: He was diagnosed as HR caused by genetic mutations in the phosphate-regulating endopeptidase homologue. Based on his family history and laboratory tests, including high serum alkaline phosphatase, high urinary phosphorus, hypophosphatemia, and normal serum calcium level, the patient was diagnosed with this disorder. INTERVENTIONS: Rotational and translational osteotomy was performed to redress the severe varus deformity and readjust the malalignment of the lower extremity. OUTCOMES: Right after the surgery, the alignment in the left lower extremity was readjusted, and his appearance seemed normal. Combined with rehabilitation and pharmacological intervention, including oral intake of phosphate and alphacalcidol, the bone healed uneventfully. After the second surgery of a similar procedure on the right femur, the patient was able to walk almost like a normal teenager. LESSONS: This case proposed a novel technique to treat severe varus or valgus deformity of the lower extremity. HR is a rare disease, and it is important to stress its recognition to avoid delay of diagnosis and surgical intervention if necessary.

2.
Cell Prolif ; : e12781, 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-32035016

RESUMO

Central nervous system (CNS) maintains a high level of metabolism, which leads to the generation of large amounts of free radicals, and it is also one of the most vulnerable organs to oxidative stress. Emerging evidences have shown that, as the key homeostatic cells in CNS, astrocytes are deeply involved in multiple aspects of CNS function including oxidative stress regulation. Besides, the redox level in CNS can in turn affect astrocytes in morphology and function. The complex and multiple roles of astrocytes indicate that their correct performance is crucial for the normal functioning of the CNS, and its dysfunction may result in the occurrence and progression of various neurological disorders. To date, the influence of astrocytes in CNS oxidative stress is rarely reviewed. Therefore, in this review we sum up the roles of astrocytes in redox regulation and the corresponding mechanisms under both normal and different pathological conditions.

3.
Cell Immunol ; : 104047, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-32019673

RESUMO

The polarization of macrophages is critical to inflammation and tissue repair, with unbalanced macrophage polarization associated with critical dysfunctions of the immune system. Cytochrome P450 1A1 (CYP1A1) is a hydroxylase mainly controlled by the inflammation-limiting aryl hydrocarbon receptor (AhR), which plays a critical role in mycoplasma infection, oxidative stress injury, and cancer. Arginase-1 (Arg-1) is a surrogate for polarized alternative macrophages and is important to the production of nitric oxide (NO) by the modulation of arginine. In the present study, we found CYP1A1 to be upregulated in IL-4-stimulated mouse peritoneal macrophages (PMs) and human peripheral blood monocytes. Using CYP1A1-overexpressing RAW264.7 cells (CYP1A1/RAW) we found that CYP1A1 augmented Arg-1 expression by strengthening the activation of the JAK1/STAT6 signaling pathway in macrophages treated with IL-4. 15(S)-HETE, a metabolite of CYP1A1 hydroxylase, was elevated in IL-4-induced CYP1A1/RAW cells. Further, in macrophages, the loss-of-CYP1A1-hydroxylase activity was associated with reduced IL-4-induced Arg-1 expression due to impaired 15(S)-HETE generation. Of importance, CYP1A1 overexpressing macrophages reduced the inflammation associated with LPS-induced peritonitis. Taken together, these findings identified a novel signaling axis, CYP1A1-15(S)-HETE-JAK1-STAT6, that may be a promising target for the proper maintenance of macrophage polarization and may also be a means by which to treat immune-related disease due to macrophage dysfunction.

4.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 34(2): 190-195, 2020 Feb 15.
Artigo em Chinês | MEDLINE | ID: mdl-32030950

RESUMO

Objective: To investigate the method and effectiveness of transosseous suture in situ technique in repairing anterior cruciate ligament (ACL) avulsion injury for the multiple ligament injuries with knee dislocation (MLIKD). Methods: The clinical data of 27 patients (27 knees) with MLIKD between September 2010 and April 2016 were analyzed retrospectively. There were 21 males and 6 females, with an average age of 42 years (range, 24-60 years). The injury was caused by traffic accident in 9 cases, heavy-weight crushing in 9 cases, sports sprain in 6 cases, falling from height in 3 cases. The interval from injury to operation was 1-19 days (mean,10.8 days). There were 20 cases of femoral avulsion injury of ACL, 7 cases of tibial avulsion injury of ACL, and there were 17 cases of posterior cruciate ligament (PCL) injuries. According to the Schenck classification, there were 15 cases of KD-Ⅲ-M type, 8 cases of KD-Ⅲ-L type, and 4 cases of KD-Ⅳ type. All patients were positive in the posterior drawer test and Lachman test; 8 cases were degree Ⅲ positive in varus stress test, and 15 cases were degree Ⅲ positive in valgus stress test. The Lysholm score of knee was 27.6±6.5, the International Knee Documentation Committee (IKDC) score was 25.5±6.2, and the range of motion (ROM) of knee was (45.1±10.2)°. The injured PCL was reconstructed with a single bundle of autologous hamstring tendon. ACL was repaired with double bundle traction by transosseous suture in situ technique. Medial cruciate ligament, lateral cruciate ligament, joint capsule, and other damaged structures were repaired at the same time. Results: All incisions healed by first intention. There were 3 cases with joint effusion and 3 cases with incomplete flexion. All patients were followed up 12-36 months (mean, 22 months). The X-ray films showed good stability in all directions. At last follow-up, the anterior and posterior drawer tests were all negative; Lachman test was degreeⅠpositive in 4 cases, valgus stress test was degreeⅠpositive in 3 cases, varus stress test was degreeⅠpositive in 1 case; and all tests were negative in the rest patients. At 1 year after operation, the ROM of knee was (119.3 ±12.6)°, Lysholm score was 87.2±6.3, and IKDC score was 87.9±6.3, showing significant differences when compared with the preoperative scores ( P<0.05). Conclusion: Transosseous suture in situ technique can be used to repair the ACL avulsion injury for MLIKD, which can significantly improve the stability, mobility and function of the knee joint, and obtain satisfied short-term effectiveness.

5.
Cytokine ; 128: 155001, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32035329

RESUMO

Neutrophilic granule protein (NGP) belongs to the cystatin superfamily. Even though this superfamily is critically involved in cancer biology and adaptive immunity, the relationship of macrophage NGP to inflammation and phagocytosis remains poorly understood. In this study, we observed a significant increase of NGP in peritoneal macrophages (PMs) isolated from mice challenged with E. coli or lipopolysaccharide (LPS), as judged by NGP mRNA microarray. We also found changes in NGP to be mainly Toll-like receptor 4 (TLR4)-dependent. By western blot and electrophoretic mobility shift assay, we demonstrated NGP overexpression to reduce TNF-α and IL-1ß production by LPS-induced RAW264.7 cells (RAW) via suppression of the NF-κB (p65 and p50) signalling pathway, rather than the JNK1/AP-1 (fos and jun) signalling pathway. NGP overexpression by LPS-induced RAW also induced IL-10, an anti-inflammatory cytokine, which was partially involved in the anti-inflammatory effect produced by NGP overexpression. Moreover, upregulated NGP enhanced the phagocytosis of E. coli by RAW. Taken together, these results demonstrated NGP to be an important host defense component that regulates inflammatory responses and phagocytosis by activated macrophages. As such, NGP may be useful for the treatment of inflammatory based disease.

6.
Ren Fail ; 42(1): 77-88, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31893969

RESUMO

Purpose: The results from randomized controlled trials (RCTs) concerning the timing of initiation of renal replacement therapy (RRT) for patients with acute kidney injury (AKI) are still inconsistent.Materials and methods: We searched for RCTs, as well as relevant references, focusing on the timing of RRT for AKI patients in the Medline, Embase, Cochrane Library, Google Scholar and Chinese databases from their inception to December 2018.Results: We included 18 RCTs from 1997 to 2018 involving 2856 patients. Pooled analyses of all RCTs showed no significant difference in mortality between early initiation and delayed initiation of RRT (RR 0.98, 95% CI: 0.89 to 1.08, p = .7) (I2 = 2%), and similar results were found in critically ill and community-acquired AKI patients, as well as in a subgroup of patients with sepsis and in cardiac surgery recipients. There was also no difference in the incidence of dialysis independence (RR 0.75, 95% CI: 0.47 to 1.2, p = .2) (I2 = 0). However, an early RRT strategy was associated with a significantly higher incidence of the need for RRT for AKI patients (RR 1.24, 95% CI: 1.13 to 1.36, p < .01) (I2 = 34%).Conclusions: As no life-threatening complications occurred, there was no evidence to show any benefit of an early RRT strategy for critically ill or community-acquired AKI patients; in contrast, a delayed strategy might avert the need for RRT.

7.
Adv Mater ; : e1906590, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31957096

RESUMO

Three-dimensional (3D) subwavelength nanostructures have emerged and triggered tremendous excitement because of their advantages over the two-dimensional (2D) counterparts in fields of plasmonics, photonic crystals, and metamaterials. However, the fabrication and integration of 3D nanophotonic structures with colloidal quantum dots (CQDs) faces several technological obstacles, as conventional lithographic and etching techniques may affect the surface chemistry of colloidal nanomaterials. Here, the direct fabrication of functional quasi-3D nanophotonic structures into CQD films is demonstrated by one-step imprinting with well-controlled precision in both vertical and lateral directions. To showcase the potential of this technique, diffraction gratings, bilayer wire-grid polarizers, and resonant metal mesh long-pass filters are imprinted on CQD films without degrading the optical and electrical properties of CQD. Furthermore, a dual-diode CQD detector into an unprecedented mid-wave infrared two-channel polarization detector is functionalized by embedding an imprinted bilayer wire-grid polarizer within the CQDs. The results show that this approach offers a feasible pathway to combine quasi-3D nanostructures with colloidal materials-based optoelectronics and access a new level of light manipulation.

8.
Mater Sci Eng C Mater Biol Appl ; 108: 110487, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31923968

RESUMO

It remains challenging to build up a multifunctional coating onto biodegradable magnesium (Mg) for biomedical use. In this study, a small amount of titanium dioxide (TiO2) has been incorporated in situ into phytic acid (PA) coating when it was chemically deposited on Mg substrate targeted to biodegradable implant applications. Ultraviolet (UV) irradiation was utilized in the liquid phase deposition of TiO2 to improve the quality of coating (PA&TiO2-UV). This PA&TiO2-UV coating was compact, thicker and more hydrophilic compared with sole PA or TiO2 coating. The PA&TiO2-UV coated Mg presented a seven times lower electrochemical corrosion current density as well as significantly slower in vitro degradation rate up to 500 h in phosphate buffer saline as compared to the direct PA coated Mg. In addition, the UV irradiation showed remarkably to promote the MC3T3-E1 pre-osteoblast cells adhesion and proliferation especially after 7 days of culture. Further, the PA&TiO2-UV coating adhered more firmly on Mg substrate after 90° bending than the other coatings, indicating a better mechanical compliance on Mg substrate. These results make this PA&TiO2-UV complex coating bodes well for biodegradation slowing-down, osteo-compatible as well as mechanical compliant modification of Mg for orthopedic implants applications.

9.
Circulation ; 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31902237

RESUMO

Background: S-nitrosylation (SNO), a prototypic redox-based posttranslational modification, is involved in the pathogenesis of cardiovascular disease. The aim of this study was to determine the role of S-nitrosylation of muscle LIM protein (MLP) in myocardial hypertrophy, as well as the mechanism by which SNO-MLP modulates hypertrophic growth in response to pressure overload. Methods: Myocardial samples from patients and animal models exhibiting myocardial hypertrophy were examined for SNO-MLP level using biotin-switch methods. S-nitrosylation sites were further identified through liquid chromatography-tandem mass spectrometry (LCMS/MS). Denitrosylation of MLP by the mutation of nitrosylation sites or overexpression of S-nitrosoglutathione reductase (GSNOR) was used to analyze the contribution of SNO-MLP in myocardial hypertrophy. Downstream effectors of SNO-MLP were screened through mass spectrometry (MS) and confirmed by co-immunoprecipitation. Recruitment of toll-like receptor 3 (TLR3) by SNO-MLP in myocardial hypertrophy was examined in TLR3 small interfering RNA (siRNA)-transfected neonatal rat cardiomyocytes (NRCMs) and in TLR3 knockout mouse model. Results: SNO-MLP level was significantly higher in hypertrophic myocardium from patients and in spontaneously hypertensive rats and mice subjected to transverse aortic constriction (TAC). The level of SNO-MLP also increased in angiotensin II (Ang II) or phenylephrine (PE)-treated NRCMs. S-nitrosylated site of MLP at cysteine (Cys) 79 was identified by LCMS/MS and further confirmed in NRCMs. Mutation of Cys79 significantly reduced hypertrophic growth in Ang II or PE-treated NRCMs and TAC mice. Reducing MLP Snitrosylation level by overexpression of S-nitrosoglutathione reductase greatly attenuated myocardial hypertrophy. Mechanistically, MLP S-nitrosylation stimulated TLR3 binding to MLP in response to hypertrophic stimuli, and disrupting this interaction by downregulating TLR3 attenuated myocardial hypertrophy. SNO-MLP also increased the complex formation between TLR3 and receptor-interacting protein kinase 3 (RIP3). This interaction in turn induced NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome activation, thereby promoting the development of myocardial hypertrophy. Conclusions: Our findings revealed a key role of SNO-MLP in myocardial hypertrophy and demonstrated TLR3-mediated RIP3 and NLRP3 inflammasome activation as the downstream signaling pathway, which may represent a novel therapeutic target for myocardial hypertrophy and heart failure.

10.
Arterioscler Thromb Vasc Biol ; 40(1): 175-188, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31694393

RESUMO

OBJECTIVE: Thoracic aortic dissection (TAD) is a fatal disease that leads to aortic rupture and sudden death. However, little is known about the effect and molecular mechanism of S-nitrosylation (SNO) modifications in TAD formation. Approach and Results: SNO levels were higher in aortic tissues from TAD patients than in those from healthy controls, and PLS3 (plastin-3) SNO was identified by liquid chromatography-tandem mass spectrometry analysis. Furthermore, tail vein administration of endothelial-specific adeno-associated viruses of mutant PLS3-C566A (denitrosylated form) suppressed the development of TAD in mice, but the wild-type PLS3 (S-nitrosylated form) virus did not. Mechanistically, Ang II (angiotensin II)-induced PLS3 SNO enhanced the association of PLS3 with both plectin and cofilin via an iNOS (inducible nitric oxide synthase)-dependent pathway in endothelial cells. The formation of PLS3/plectin/cofilin complex promoted cell migration and tube formation but weakened adherens junction formation in Ang II-treated endothelial cells. Interestingly, denitrosylated form of PLS3 partially mitigated Ang II-induced PLS3/plectin/cofilin complex formation and cell junction disruption. Additionally, the inhibition of iNOS attenuated PLS3 SNO and the association of PLS3 with plectin and cofilin, thereby modulating endothelial barrier function. CONCLUSIONS: Our data indicate that protein SNO modification in endothelial cells modulates the progression of aortic aneurysm and dissection. The iNOS-mediated SNO of PLS3 at the Cys566 site promoted its interaction with cofilin and plectin, thus contributing to endothelial barrier disruption and pathological angiogenesis in TAD.

11.
Dig Liver Dis ; 52(2): 143-148, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31401021

RESUMO

BACKGROUND AND AIMS: The SPINK1 c.194 + 2T > C variant has been increasingly recognized as an important risk factor for chronic pancreatitis (CP). However, there is no clear agreement on its contribution to different ethnicities and CP etiologies. To address this issue, a meta-analysis of literature was performed. METHODS: Studies addressing the presence of the SPINK1 c.194 + 2T > C variant in CP patients and controls were retrieved from the PubMed, EMBASE and Cochrane databases. Initial analysis included all CP patients, followed by subgroup analyses for East Asian and non-East Asian patients, and for idiopathic CP (ICP) and non-ICP. RESULTS: A total of 13 studies were retrieved for analysis, comprising 2097 cases and 4019 controls. There were 126 cases (10.01%) carrying the SPINK1 c.194 + 2T > C variant in cases, while only two controls were carriers (0.05%). Overall, the variant was significantly associated with an increased risk of CP (OR = 25.73). In the subgroup, the variant was significantly associated with increased risk of CP in East Asians (OR = 73.16), and in non-East Asians (OR = 10.21). Further, the contribution of the variant in ICP (OR = 35.31) was found to be higher than in non-ICP (25.75). CONCLUSIONS: The SPINK1 c.194 + 2T > C variant is a strong risk factor for CP, especially in East Asian patients with ICP.

12.
Genome ; 63(1): 1-12, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31533014

RESUMO

The larvae of Holotrichia parallela, a destructive belowground herbivore, causes tremendous damages to maize plants. However, little is known if there are any defense mechanisms in maize roots to defend themselves against this herbivore. In the current research, we carried out RNA-sequencing to investigate the changes in gene transcription level in maize roots after H. parallela larvae infestation. A total of 644 up-regulated genes and 474 down-regulated genes was found. In addition, Gene ontology (GO) annotation analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed. Weighted gene co-expression network analysis (WGCNA) indicated that peroxidase genes may be the hub genes that regulate maize defenses to H. parallela larvae attack. We also found 105 transcription factors, 44 hormone-related genes, and 62 secondary metabolism-related genes within differentially expressed genes (DEGs). Furthermore, the expression profiles of 12 DEGs from the transcriptome analysis were confirmed by quantitative real-time PCR experiments. This transcriptome analysis provides insights into the molecular mechanisms of the underground defense in maize roots to H. parallela larvae attack and will help to select target genes of maize for defense against belowground herbivory.

14.
Dev Comp Immunol ; 105: 103584, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31863792

RESUMO

Clip-domain serine proteases (CLIPs), characterized by regulatory module clip domains, constitute an important serine protease family identified in insects and other arthropods. They participate in host immune response and embryonic development in a cascade-activated manner. Here, we present a genome-wide identification and expression analysis of CLIP genes in the silkworm, Bombyx mori. A total of 26 CLIP genes were identified in the silkworm genome. Bioinformatics analysis indicated that these CLIPs clustered into four subfamilies (CLIPA-D), and exhibit a close evolutionary relationship with CLIPs of Manduca sexta. Tissue expression profiling revealed that silkworm CLIP genes are mainly expressed in the integument, head, fat body, and hemocytes. Temporal expression profiles showed that 15 CLIP genes were predominantly expressed during the fifth-instar larval stage, early and later period of the pupal stage, and adult stage, whereas 10 CLIP genes were mainly expressed in the wandering stage and middle to later period of the pupal stage in the integument. Pathogens and 20-hydroxyecdysone (20E) induction analysis indicated that 14 CLIP genes were positively regulated by 20E, 9 were negatively regulated by 20E but positively regulated by pathogens, and 5 were positively regulated by both factors in the integument. Together, these results suggested that silkworm CLIP genes may play multiple functions in integument development, including melanization of new cuticle, molting and immune defense. Our data provide a comprehensive understanding of CLIP genes in the silkworm integument and lays a foundation for further functional studies of CLIP genes in the silkworm.

15.
Orthop Surg ; 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31788965

RESUMO

OBJECTIVE: To assess the safety and effectiveness of one-stage total joint arthroplasty (TJA) or revision for seronegative infections after total hip arthroplasty (THA) and total knee arthroplasty (TKA). METHODS: This retrospective study included a total of 495 patients who had undergone one-stage total joint (hip or knee) arthroplasty or revision with a diagnosis of osteoarthritis secondary to sepsis, osteoarthritis or osteonecrosis of the femoral head (ONFH) secondary to internal fixation surgery of the hip joint, and one-stage revision for prosthesis loosening after THA or TKA from January 2012 to December 2016. Bacterial cultures were taken from all patients (from joint fluid or articular cavity fluid and four to six different parts of soft tissues) during the operation. If the cultures were positive, patients received antibiotic treatment. Microbiology results from surgical samples, clinical evaluations, SF-12 score (physical component summary [PCS] and mental component summary [MCS]), Harris hip score (HHS) or Hospital for Special Surgery (HSS) score, and patients' satisfaction was recorded at every follow-up session. RESULTS: A total of 24 patients had a positive result for bacterial culture (4.85%). The bacterial culture results showed that there were 19 cases (79.16%) of gram-positive cocci (Staphylococcus aureus), 4 cases (16.67%) of gram-negative bacilli, and 1 case (4.17%) of fungi. For at least 24 months (mean 35 months) follow-up, no reinfection was discovered. The mean HHS or HSS score improved significantly from 36.29 points preoperatively to 84.21 points postoperatively (P < 0.001). The mean PCS score improved from 10.15 preoperatively to 20.34 postoperatively, and the mean MCS from 13.22 preoperatively to 21.76 postoperatively, with significant differences. Most of the patients were satisfied. CONCLUSION: One-stage arthroplasty or revision with exhaustive debridement, adequate dosage, and duration of sensitive antibiotics is safe and effective for patients who have seronegative infection of hip or knee joints.

16.
Inflammation ; 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31802382

RESUMO

Ellipticine, a natural product from Ochrosia elliptica, has been broadly investigated for its anticancer effects. Although inflammation has been clearly identified as a key factor in the onset and progression of cancer, the relationship between ellipticine and inflammation remains unknown. Hence, the aims of the present study were to assess the effects of ellipticine on the inflammatory responses to lipopolysaccharide (LPS)-induced macrophages and to potentially identify the underlying mechanisms involved. Viability testing showed that ellipticine was not significantly toxic to Raw264.7 cells and actually conveyed protective effects to LPS-stimulated Raw264.7 cells and human peripheral blood monocytes by decreasing the secretion of inflammatory factors (TNF-α and IL-6). The results of western blot analysis and electrophoretic mobility shift assays showed that ellipticine markedly suppressed LPS-induced activation of the JNK/AP-1 (c-Fos and c-Jun) signaling pathway, but not ERK/p38/NF-κB pathway (p65 and p50) activation. Furthermore, ellipticine reduced the inflammatory response and mortality in a mouse model of LPS-induced endotoxic shock. Collectively, these data indicate that ellipticine may be a potential therapeutic agent for the treatment of inflammation-associated diseases.

17.
Medicine (Baltimore) ; 98(52): e18439, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31876724

RESUMO

BACKGROUND: Our previous three-dimensional finite element analysis found that posterior cruciate ligament (PCL) reconstruction in the modified tibial tunneling placement (MTT, 10 mm inferior and 5 mm lateral to the PCL anatomical insertion) could reduce the peak stress of the graft and may reduce the killer turn. The purpose of the current study was to compare the biomechanical results between MTT and traditional tibial tunneling technique (TTT, PCL anatomical insertion) during transtibial PCL reconstruction. METHODS: Fifty-six 3D-printed tibia models and fresh mature porcine flexor digitorum tendons were studied. The PCL reconstruction specimens were randomly divided into TTT group and MTT group based on tibial tunnel placement. A 50 to 300 N cyclic loading was applied using a material testing system. Each specimen completed 2000 cycles at a rate of 200 mm/min and a loading frequency of 80 cycles/min. Load-displacement curves, failure mode, and graft displacement were recorded. Mean maximum contact pressure was measured using a pressure-sensitive film. After cyclic loading test, the surviving grafts were randomly assigned to load-to-failure group or Scanning Electron Microscopy (SEM) group. Ultimate failure load and the appearance of graft abrasion were recorded and analyzed. RESULT: During the cyclic loading test, 3 samples in the TTT group, and 2 in the MTT group were excluded because of the graft pullout during the test. Mean maximum contact pressure of killer turn was 9.30 ±â€Š0.29 MPa in the TTT group and 7.27 ±â€Š0.25 MPa in MTT group (P < .05). Mean graft displacement was 4.54 ±â€Š0.23 mm in the TTT group and 3.37 ±â€Š3.56 mm in the MTT group (P < .05). Maximum failure load was 1886.0 ±â€Š41.83 N in the TTT group and 2019.30 ±â€Š20.10 N in the MTT group (P < .05). The SEM analysis showed heavy abrasion and fiber discontinuity in graft in the TTT group, while it showed slight abrasion and fiber arrangement disorders in the MTT group. CONCLUSIONS: The MTT PCL reconstruction significantly reduced stress concentration and graft abrasion as compared with the TTT PCL reconstruction, and it may be a better choice for the reduction of "killer Turn" effect during transtibial PCL construction.


Assuntos
Ligamento Cruzado Posterior/transplante , Procedimentos Cirúrgicos Reconstrutivos/métodos , Fenômenos Biomecânicos , Humanos , Microscopia Eletrônica de Varredura , Modelos Anatômicos , Ligamento Cruzado Posterior/cirurgia , Suporte de Carga
18.
BMC Musculoskelet Disord ; 20(1): 614, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31870350

RESUMO

BACKGROUND: At present, most repair techniques for meniscal tears fix the meniscus directly over the capsule. This changes the normal anatomy and biomechanics and limits the activity of the meniscus during motion. We introduce an arthroscopic repair technique by suturing the true meniscus tissue without the capsule and subcutaneous tissue. METHODS: After confirmation of a tear, a custom-designed meniscal repair needle first penetrates percutaneously, crossing the capsular portion and the torn meniscus, and exits from the femoral surface of one side of the torn meniscus. Then a No. 2 PDS suture is passed through the needle and retrieved through the arthroscopy portal. Next, the needle is withdrawn to the synovial margin of the meniscus and is reinserted, exiting the femoral surface of the other side of the torn meniscus. The suture is pulled out through the same portal with a grasper. Finally, arthroscopic knotting is performed. RESULTS: We had 149 cases of meniscal tears repaired with this outside-in transfer all-inside technique since July 2016. CONCLUSIONS: It is a simple, minimally invasive, and economical procedure that is appropriate for most parts of the meniscus except the posterior horn of the lateral meniscus, and it can be used to fix torn meniscus tissue firmly while also preserving the inherent activity of the meniscus.

19.
BMC Musculoskelet Disord ; 20(1): 521, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699065

RESUMO

BACKGROUND: The killer turn has been documented as the primary drawback of posterior cruciate ligament (PCL) reconstruction. Fanelli advocated placing the tibial tunnel outlet in the inferior lateral part of the PCL fovea to reduce the killer turn. This study aimed to confirm the validity of Fanelli's viewpoint regarding PCL reconstruction technique and to assess the specific Fanelli tunnel area on the inferior lateral part of the PCL fovea. METHODS: The geometrical data of the model were obtained by nuclear magnetic resonance (MRI) and computerized tomography (CT), with images taken from a healthy Chinese volunteer. The three-dimensional finite element model of the knee joint was established using Mimics, Geomagic Studio, 3-matic, and Ansys software. The finite analysis was performed after the material behavior, contact and boundary conditions, and loading were defined. The drawer tests were simulated with a posterior tibial load of 134 N at 0°, 30°, 60°, and 90° knee flexion. The PCL peak stress and tibial translation were recorded and compared among the 30 distinct tibial tunnel loci over a range of angles from 0° to 90°. RESULTS: In the area (Fanelli area, 5-20 mm inferior and 5-10 mm lateral to the PCL anatomical insertion), the lowest PCL peak stress in all sites with different flexion angles was lower than that of the PCL anatomical insertion site. The lowest PCL peak stress with different knee flexion angles was observed in the following location: 10 mm inferior and 5 mm lateral to the PCL anatomical insertion. In the Fanelli area, the tibial translations of three sites were lower and those of other sites were higher than that of the PCL anatomical insertion site. CONCLUSIONS: PCL reconstruction in the Fanelli area, especially 10 mm inferior and 5 mm lateral to the PCL anatomical insertion, could reduce the peak stress of the graft and may reduce the killer turn. However, whether the posterior stability of the knee is affected needs to be further studied.

20.
J Biomed Res ; 0(0): 1-9, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31741464

RESUMO

Cardiac fibrosis is a common pathological change of many cardiovascular diseases. ß-catenin has been shown to promote fibrosis. However, the precise role of its homolog γ-catenin in the process of fibrosis remains largely unclear. In this study, we found that the expression of γ-catenin was significantly decreased in angiotensin Ⅱ (Ang Ⅱ)-induced cardiac fibrosis model, contrary to most reports of ß-catenin. Overexpression of γ-catenin in cardiac fibroblasts (CFs) significantly inhibited the expression of α-smooth muscle actin (α-SMA), whereas knocking down the expression of γ-catenin with siRNA promoted the occurrence of cardiac fibrosis. Mechanistically, γ-catenin could bind to GSK-3ß to inhibit the phosphorylation of GSK-3ß, therefore preventing cardiac fibrosis. Our study shows that γ-catenin is an important protective factor in cardiac fibrosis, which provides a new potential target for the treatment of cardiac fibrosis.

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