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1.
Orthop Surg ; 12(1): 218-223, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32077259

RESUMO

OBJECTIVE: To investigate the temporal relationship of medial unicompartmental knee arthroplasty (UKA) and forgotten joint score (FJS), and to analysis the predictive factors associated with FJS after medial UKA. METHODS: This is a cross-sectional observational study. A total of 188 cases of medial UKA were included in this study, and all the prostheses used were Oxford mobile-bearing UKA from January 2016 to January 2019. All patients have completed the questionnaire of FJS, and the relevant data were obtained for 1 month (n = 38), 6 month (n = 40), 12 month (n = 42), 24 month (n = 34), and 36 month (n = 34) patient subgroups. The score ranged from 0-100, with a higher score indicating a more natural knee joint. In addition, the associations between the potential influencing factors (body mass index [BMI], age, gender, duration of onset before surgery, Kellgren-Lawrence grade of the medial compartment before surgery) with FJS were analyzed using Pearson correlation and multiple linear regression. RESULTS: Postoperative FJSs were 44.5 ± 13.5 at 1 month,63.8 ± 10.1 at 6 months, 77.1 ± 12.2 at 12 months, 78.4 ± 12.2 at 24 months, 78.9 ± 12.5 at 36 months. The postoperative FJSs were lowest at 1 month and highest at 36 month (P < 0.01). The mean value of FJS kept improving until 12 months post-operation, which was slightly lower than that of 24 months and 36 months, but there was no statistical difference between them. Pearson correlation and multiple linear regression analysis showed that gender and Kellgren-Lawrence grade of the medial compartment before surgery had no significant influence on FJS, while age, BMI, and duration of onset before surgery had significant associations with FJS after UKA. BMI was negatively correlated with FJS, while older patients (>60) and with longer duration of onset before surgery (>3 years) were a positive predictor of good outcome for the FJS. CONCLUSION: Patients can expect marked improvement in the natural feel of the prosthesis during the first year after UKA, slight continued improvement at 2 and 3 years. Furthermore, we identified three preoperative patient-related factors (age, BMI, and duration of onset before surgery) that may predict the FJS after medial UKA, which can be used to guide surgical decision making.

2.
Knee ; 27(1): 9-17, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31864659

RESUMO

BACKGROUND: To evaluate the clinical outcomes of combined medial and lateral patellar retinaculum plasty for skeletally immature patients with patellar dislocation and low-grade trochlear dysplasia. METHODS: From December 2014 to December 2016, we reviewed 19 skeletally immature patients who underwent medial and lateral patellar retinaculum plasty at our institution. Clinical evaluations were performed pre- and postoperatively, and included determination of the number of patellar re-dislocation patients, the Kujala and Tegner scores, the patellar tilt angle, lateral patellar shift, and congruence angle. The radiographic evaluation parameters were measured on computed tomography scans. RESULTS: No dislocation or subluxation occurred during the mean follow-up of 35.42 months (24-48 months). Postoperatively, the Kujala score improved from 57.6 ±â€¯4.2 to 86.9 ±â€¯8.1 (P < 0.05), and the Tegner activity score improved from 2.6 ±â€¯1.0 to 5.0 ±â€¯1.3 (P < 0.05). Radiographically, the patellar tilt angle decreased from 32.7 ±â€¯5.9° to 13.4 ±â€¯4.28° (P < 0.05), the lateral patellar shift decreased from 15.9 ±â€¯1.1 mm to 8.4 ±â€¯0.6 mm (P < 0.05), and the congruence angle decreased from 29.9 ±â€¯15.3° to -9.6 ±â€¯15.5° (P < 0.05). CONCLUSIONS: Medial and lateral patellar retinaculum plasty is a promising procedure that has the advantage of being a simple operation that induces little trauma. It is a good treatment option for skeletally immature patients with patellar dislocation who have low-grade trochlear dysplasia.

3.
Connect Tissue Res ; : 1-14, 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31829044

RESUMO

Purpose: Trochlear dysplasia is one of the most frequent lower extremities deformities. Aim of this research was to investigate the changes in cartilage and subchondral bone of trochlea after patellar dislocation in growing rabbits. Materials and Methods: Ninety-six knees from 48 one-month-old rabbits were divided into two groups (experimental, control). Lateral patellar dislocation was established in the experimental group and distal femurs were collected at 4, 8, 12 and 24-week time points, respectively. General examination and histological observations were conducted to research the anatomical structure of the trochlear cartilage and subchondral bone. Structural parameters of trochlear subchondral bone were measured by MicroCT. Subsequently, the expression of TRPV4, collagen II and MMP-13 in cartilage were detected by western blot and RT-PCR analysis, respectively.Results: Subchondral bone loss was found in experimental group from 4 weeks after patellar dislocation, accompanied by increased TRAP-positive osteoclasts in subchondral bone. The trochlear dysplasia model was well established from 8 weeks after patellar dislocation. In addition, degeneration of cartilage was found from 8 weeks, accompanied by decreased expression of mechanically sensitive TRPV4 and collagen II, and increased expression of MMP-13.Conclusions: This study proved that trochlear dysplasia can be caused by patellar dislocation in growing rabbits, accompanied by significant subchondral bone loss. What is more, this study also shows that degenerative cartilage changes occur in the patellar dislocation model and become aggravated with time, accompanied by decreased TRPV4 and collagen II, but increased MMP-13.

4.
BMC Musculoskelet Disord ; 20(1): 411, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488123

RESUMO

BACKGROUND: Developmental factors were assumed to be the key factors that influenced the morphology of femoral trochlea. This study investigated the effects of insufficient patellar stress after birth on the morphological development of the femoral trochlea. Effects of insufficient patellar stress on femoral trochlea were investigated using surgical induced patellectomy and patellar dislocation in growing rat model. METHODS: In this study, two experimental groups and one sham group (SG) were established. Thirty-six Wistar rats (female, 28 days of age) were randomly assigned to three groups. The patellectomy group (PG), rats underwent the patellectomy in this group. The dislocation group (DG), rats underwent the surgery-induced patellar dislocation. Histological staining (Safranin-O and fast green), Micro-computed tomographic (Micro-CT) analysis in two experimental endpoints (3, 12 weeks postoperatively) were selected to evaluate morphological changes of the femoral trochlea. RESULTS: Articular cartilage on the trochlear sulcus was remodeled at 3 weeks after the surgery, and degenerated at 12 weeks through the histological staining. The femoral trochlear angle (FTA) did not show a significant difference at 3 week between the experimental groups and the sham group (PG vs SG P = 0.38, DG vs SG p = 0.05), but the FTA was significantly increased in experimental groups at 12 weeks(PG vs SG P = 0.001, DG vs SG p = 0.005). The Bone volume density (BV/TV), Trabecular number (Tb.N) under the trochlea groove were significantly reduced at 3 weeks postoperatively in the experimental groups (PG vs SG p = 0.001, DG vs SG p = 0.002). No significant difference was found in BV/TV and Tb. N among the three groups at 12 weeks postoperatively. CONCLUSION: Surgical induced patellectomy and patellar dislocation leads to the dysplastic trochlear sulcus in growing rats. Besides the bone morphology of trochlear sulcus, the articular cartilage and subchondral trabecula under the trochlear sulcus were remodeled early stage after the surgery.

5.
Orthop Surg ; 11(4): 578-585, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31419069

RESUMO

OBJECTIVES: To report the clinical outcomes of combined femoral derotation osteotomy and medial retinaculum plasty for recurrent patellar dislocation in patients with excessive femoral anteversion. METHODS: From January 2015 to March 2018, 20 knees in 20 patients (18 female, 2 male) with a mean age of 21 ± 4.2 years (range, 16 to 28 years) were retrospectively reviewed. All patients had undergone femoral derotation osteotomy and medial retinaculum plasty for recurrent patellar dislocation and excessive femoral anteversion angle (FAA > 25°). CT and X-rays were used to assess the correction of the femoral anteversion angle, the tibia tuberosity-trochlear groove (TT-TG) distance, patellar tilt, and the congruence angle following the combinatory operations. Subjective scores, such as Kujala, International Knee Documentation Committee (IKDC), Tegner, and visual analogue scale (VAS) scores, were used to evaluate knee function preoperatively and postoperatively. RESULTS: No recurrence of patellar dislocation occurred in these patients during an average of 18 months (range, 12 to 23 months) of follow-up. The mean of the FAA was corrected to 15.80° ± 3.58° postoperatively compared with 31.42° ± 4.95° preoperatively (P < 0.001). The TT-TG distance was decreased from 22.17 ± 5.28 mm before surgery to 19.42 ± 4.57 mm after surgery (P = 0.03). The patellar tilt and congruence angle were improved from 30.43° ± 5.30°, 43.30° ± 11.04° to 15.80° ± 3.94°, 16.64° ± 9.98°, respectively (P < 0.001). The Kujala score was improved from 72.4 ± 19.90 before the surgery to 88.2 ± 12.25 after the surgery (P < 0.001). The IKDC score was improved from 70.56 ± 21.44 to 90.78 ± 14.32, and the VAS score was decreased from 4.23 ± 2.11 preoperatively to 1.27 ± 1.08 postoperatively (P < 0.001). No significant difference in Tegner score (5.46 ± 2.49 vs 5.79 ± 1.44) was found before and after the surgery (P = 0.2). Patients younger than 20 years old had lower Kujala (83.46 ± 14.56 vs. 90.84 ± 7.74, P = 0.02) and IKDC (83.49 ± 17.35 vs 92.46 ± 9.28, P = 0.04) scores than those older than 20 years. CONCLUSION: Good knee function, pain relief, and improved patellofemoral congruence were achieved with the combined femoral derotation osteotomy and medial retinaculum plasty. The combined operations serve as an ideal treatment for recurrent patellar dislocation and address the primary risk factors.

6.
ACS Omega ; 4(8): 13209-13217, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31460448

RESUMO

We explore the stability, electronic properties, and quantum capacitance of doped/co-doped graphene with B, N, P, and S atoms based on first-principles methods. B, N, P, and S atoms are strongly bonded with graphene, and all of the relaxed systems exhibit metallic behavior. While graphene with high surface area can enhance the double-layer capacitance, its low quantum capacitance limits its application in supercapacitors. This is a direct result of the limited density of states near the Dirac point in pristine graphene. We find that the triple N and S doping with single vacancy exhibits a relatively stable structure and high quantum capacitance. It is proposed that they could be used as ideal electrode materials for symmetry supercapacitors. The advantages of some co-doped graphene systems have been demonstrated by calculating quantum capacitance. We find that the N/S and N/P co-doped graphene with single vacancy is suitable for asymmetric supercapacitors. The enhanced quantum capacitance contributes to the formation of localized states near the Dirac point and/or Fermi-level shifts by introducing the dopant and vacancy complex.

7.
J Biomater Sci Polym Ed ; 30(7): 547-560, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30897033

RESUMO

Bioresorbable vascular scaffolds are expected to replace the traditional metal stent, avoiding the long-term complications of metal stents. However, it is hard for the traditional scaffold manufacturing process to meet the requirements of individualized treatment for vascular lesions, which requires different morphologies. Here, we used a new method of scaffold manufacturing, three-dimensional printing technology, to prepare bioresorbable vascular scaffolds. The fabricated scaffold was loaded with sirolimus mixed with scaffold preparation material for slow drug release. The engineered, drug- loaded, bioresorbable vascular scaffold (BVS) was analyzed and tested in vivo. The scaffolds produced by three-dimensional printing technology exhibited good mechanical properties and in vitro degradation performance. The results also suggested that these scaffolds could maintain effective radial strength after long-term degradation and sustained release of the drug. As a new scaffold preparation method, it may provide a promising idea for developing bioresorbable vascular scaffold technology.

8.
Andrologia ; 51(5): e13248, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30740770

RESUMO

Elevated platelet levels have been postulated to be associated with cardiovascular diseases, conditions closely linked to erectile dysfunction (ED). The current systematic review and meta-analysis was performed to assess the platelet indices, which including platelet count (PLT), mean platelet volume (MPV) and platelet distribution width (PDW) in subjects with ED compared to controls in an attempt to clarify the possible role of platelet indices in the pathogenesis of ED. We initially screened the candidate studies observing the possible association between platelet indices and ED following literature search of database Cochrane Library, PubMed, EMBASE and MEDLINE and therefore included the studies based on the pre-defined inclusion and exclusion criteria. Two independent investigators extracted the related information on article data and outcome measures from the qualified studies, and a meta-analysis was therefore performed using Stata 12.0 software. Subgroup analyses were conducted by the different ED aetiology obtained from the eligible studies. The standard mean difference (SMD) and the corresponding 95% confidence intervals (95% CIs) were applied to estimate the outcome measures. A total of 14 articles were qualified in our meta-analysis with a total of 1595 cases and 987 controls included. Pooled estimate was in favour of increased MPV levels in subjects with ED with a SMD of 0.651 fl, 95% CI 0.567-0.735, p = 0.000. Subgroup analysis showed that vasculogenic ED had a higher MPV levels than controls as well (SMD [95% CI] = 1.026 [0.823-1.228], p = 0.000). However, pooled analysis based on PLT and PDW levels has produced inconsistent results and not strong evidence on platelet level and ED correlation. In conclusion, vasculogenic ED patients had a higher MPV level in our study. However, the results need further interpretation with caution and more high-quality studies are warranted.


Assuntos
Plaquetas , Impotência Vasculogênica/sangue , Volume Plaquetário Médio , Humanos , Masculino , Contagem de Plaquetas
9.
Environ Sci Pollut Res Int ; 25(23): 22368-22377, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28799041

RESUMO

The proper handling of low-level radioactive waste is crucial to promote the sustainable development of nuclear power. Research into the mechanism for interactions between bacterium and radionuclides is the starting point for achieving successful remediation of radionuclides with microorganisms. Using Sr(II) as a simulation radionuclide and the mixed microorganisms of Saccharomyces cerevisiae and Bacillus subtilis as the biological adsorbent, this study investigates behavior at the interface between Sr(II) and the microorganisms as well as the mechanisms governing that behavior. The results show that the optimal ratio of mixed microorganisms is S. cerevisiae 2.0 g L-1 to B. subtilis 0.05 g L-1, and the optimal pH is about 6.3. Sr(II) biosorption onto the mixed microorganisms is spontaneous and endothermic in nature. The kinetics and the equilibrium isotherm data of the biosorption process can be described with pseudo-second-order equation and the Langmuir isotherm equation, respectively. The key interaction between the biological adsorbent and Sr(II) involves shared electronic pairs arising from chemical reactions via bond complexation or electronic exchange, and spectral and energy spectrum analysis show that functional groups (e.g., hydroxyl, carboxyl, amino, amide) at the interface between the radionuclide and the mixed microorganisms are the main active sites of the interface reactions.


Assuntos
Bacillus subtilis/metabolismo , Saccharomyces cerevisiae/metabolismo , Estrôncio/farmacocinética , Adsorção , Bacillus subtilis/efeitos dos fármacos , Biodegradação Ambiental , Técnicas de Cocultura , Concentração de Íons de Hidrogênio , Cinética , Saccharomyces cerevisiae/efeitos dos fármacos , Radioisótopos de Estrôncio/farmacocinética , Temperatura Ambiente , Fatores de Tempo
10.
Chem Commun (Camb) ; 50(5): 557-9, 2014 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-24270453

RESUMO

An amorphous metal-free N-doped carbon film prepared by sputtering and annealing exhibits comparable electrocatalytic activity and superior stability and methanol tolerance to the commercial Pt/C catalyst via a four-electron pathway for oxygen reduction reaction (ORR). Pyridinic nitrogen in films plays a key role in electrocatalytic activity for ORR.

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