In this study, a novel artificial intervertebral disc implant with modified “Bucklicrystal” structure was designed and 3D printed using thermoplastic polyurethane. The new implant has a unique ...auxetic structure with building blocks joined “face-to-face”. The accompanied negative Poisson’s ratio enables its excellent energy absorption and stability under compression. The deformation and load distribution behavior of the implant under various loading conditions (bending, torsion, extension and flexion) has been thoroughly evaluated through finite element method. Results show that, compared to natural intervertebral disc and conventional 3D implant, our new implant exhibits more effective stress transfer and attenuation under practical loading conditions. The implant's ability to contract laterally under compression can be potentially used to alleviate the symptoms of lumbar disc herniation. Finally, the biocompatibility of the implant was assessed in vitro and its ability to restore the physiological function of the disc segment was validated in vivo using an animal model.
An auxetic scaffold with uniquely modified “Bucklicrystal” structure prepared by 3D printing, which can effectively alleviate lumbar disc herniation (LDH) due to auxetic effect. The superior mechanical properties (stress distribution, stiffness, strength, energy absorption and dissipation), biocompatibility and potential to restore the disc physiological functions been proved by FEA, in vitro and in vivo studies. Display omitted
•Auxetic-structured IVD implant features negative Poisson's ratio (NPR) behavior.•Modified “Bucklicrystal”structure exhibits better energy absorption and stability.•The stress effectively and evenly transfers/attenuates in the auxetic implant.•Auxetic implant potentially alleviates the symptoms of lumbar disc herniation.
Objective
Recently, the MRI‐based vertebral bone quality (VBQ) score has been shown to correlate with Hounsfeld units (HU) value, dual‐energy X‐ray absorptiometry (DEXA) T‐score and predict ...osteoporotic fractures. Preoperative cervical HU value is an independent correlative factor for early titanium mesh cage (TMC) subsidence after anterior cervical corpectomy and fusion (ACCF). However, to date the direct association between cervical VBQ score and TMC subsidence has not been studied. This study aims to investigate the predictive effect of cervical VBQ score derived from sagittal non‐contrast‐enhanced T1‐weighted MRI on the early TMC subsidence after ACCF.
Methods
Patients who underwent one‐level ACCF from January 2016 to January 2020 were included. We retrospectively collected baseline data on age, sex, body mass index (BMI), disease type, level of surgery and radiology parameters. The cervical VBQ score was measured using preoperative non‐contrast‐enhanced T1‐weighted MRI. Univariate and multivariate logistic regression analysis were performed to screen the independent risk factors of TMC subsidence. The receiver operating characteristic (ROC) curve and area under curve (AUC) were performed to assess the predictive ability of TMC subsidence based on the cervical VBQ score. Spearman correlation analysis was used to determine the correlations between the cervical VBQ score and TMC subsidence.
Results
A total of 134 patients who underwent one‐level ACCF were included in this study, and 46 (34.33%) patients had TMC subsidence. Univariable analyses demonstrated that the age, TMC placement depth and VBQ score were associated with subsidence. The cervical VBQ score in the subsidence group was significantly higher than that in the no subsidence group (3.75 ± 0.45 vs. 3.20 ± 0.42, p < 0.001). The multivariate logistic regression analysis proved that the higher VBQ score (odds ratioOR = 13.563, 95% confidence interval CI 4.968 ‐ 37.031, p < 0.001) was the only variable that significantly predicted subsidence. Using a VBQ score cutoff value of 3.445, the cervical VBQ score yielded a sensitivity of 69.6% and a specificity of 85.2% with an AUC of 0.810 to differentiate patients with subsidence and with no subsidence.
Conclusion
Preoperative higher cervical VBQ score is an independent risk factor for TMC subsidence after ACCF. The cervical VBQ score may be a valuable tool for assisting in distinguishing the presence of TMC subsidence.
Preoperative higher cervical vertebral bone quality (VBQ) score is an independent risk factor for titanium mesh cage subsidence after anterior cervical corpectomy and fusion. The cervical VBQ score may be a valuable tool for assisting in distinguishing the presence of TMC subsidence.
Numerous studies have investigated the associations between herpesviruses and chronic periodontitis; however, the results remain controversial. To derive a more precise estimation, a meta-analysis on ...all available studies was performed to identify the association between herpesviruses and chronic periodontitis.
A computerized literature search was conducted in December 2014 to identify eligible case-control studies from the PUBMED and EMBASE databases according to inclusion and exclusion criteria. Data were extracted and pooled odds ratios (OR) with 95% confidence intervals (CI) were used to assess the association between herpesviruses and risk of chronic periodontitis. A fixed or random effects model was determined based on a heterogeneity test. Sensitivity analysis was conducted to investigate stability and reliability. Publication bias was investigated using the Begg rank correlation test and Egger's funnel plot.
Ten eligible studies were included to investigate the association between Epstein-Barr virus (EBV) and chronic periodontitis. The results showed that EBV has a significant association with chronic periodontitis compared with periodontally healthy group (OR = 5.74, 95% CI = 2.53-13.00, P<0.001). The association between human cytomegalovirus (HCMV) and chronic periodontitis was analyzed in 10 studies. The pooled result showed that HCMV also has a significant association with chronic periodontitis (OR = 3.59, 95% CI = 1.41-9.16, P = 0.007). Similar results were found in the sensitivity analyses. No significant publication bias was observed. Two eligible studies were included to investigate the association between herpes simplex virus (HSV) and chronic periodontitis risk. The association between HSV and chronic periodontitis was inconclusive (OR = 2.81 95% CI = 0.95-8.27, P = 0.06). Only one included study investigated the association between human herpesvirus 7 (HHV-7) and chronic periodontitis risk (OR = 1.00, 95% CI = 0.21-4.86).
The findings of this meta-analysis suggest that two members of the herpesvirus family, EBV and HCMV, are significantly associated with chronic periodontitis. There is insufficient evidence to support associations between HSV, HHV-7 and chronic periodontitis.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Primary Trigeminal Neuralgia (PTN) is a common and refractory neurological disease. Conventional vascular compression theory could not completely explain the etiology and pathogenesis of PTN. This ...study used diffusion tensor imaging (DTI) to demonstrate the microstructural changes of root entry zone (REZ) region in PTN patients.
DTI sequences was performed on PTN patients and healthy controls (HCs). Clinical data included affected side, disease course and visual analogue scale (VAS) were collected. Quantitative DTI variables such as FA, MD, AD and RD of the root entry/Exit zone (REZ) were measured and compared in PTN/HCs, affected/unaffected side, and pre/post operation groups. The PCoA was established to conduct overall differences between PTN group and the HCs.
A total of 17 patients with PTN (mean age 59.29 ± 8.53; 5 men) and 34 HCs (mean age 57.70 ± 6.37; 10 men) were included. Lower FA value of the affected side of PTN group was observed compared to the unaffected side and the HCs (
= 0.001), whereas the values of MD, AD and RD were significantly increased (
< 0.001). Moreover, the decrease of FA value was recovered post operation. PCoA results of the comprehensive indexes can significantly distinguish PTN group from HCs (
= 0.500,
< 0.001).
Quantitative variables derived from DTI in REZ had significantly different profiles between PTN patients and HCs, which were associated with VAS situation and the disease course of PTN. The comprehensive index established on DTI variables were of great potential to reveal the microstructure changes in PTN patients and predict the therapeutic effect.
This letter presents a pixel-based motion estimation scheme assisted with the coded texture video for depth inter-prediction, in view of motion similarity between depth and texture video. The ...proposed scheme can achieve higher inter-prediction gain without transmitting any motion vector in the pixel-based motion estimation. Coupled with depth-texture structure similarity, the inter prediction method is further extended to an integrated prediction approach by making use of both intra and inter information. Experimental results show that our proposed method achieves superior rate-distortion performance.
Patient compliance is essential to the effectiveness of brace treatment for adolescent idiopathic scoliosis (AIS) patients. Subjective measurements like questionnaires and inquiries proved to be ...arguably inaccurate. Although some scholars have applied temperature/force monitors to measuring patient compliance objectively, few studies to date could monitor patient compliance in real time. The objective of this study is to describe and evaluate a compliance real-time monitoring system of the brace usage in AIS patients.
A compliance real-time monitoring system (specifically consisting of a compliance monitor, a WeChat Mini Program, a cloud-based storage system and a website backstage management system) was designed to manage the brace treatment. Thirty patients receiving brace treatment were enrolled. They were told to upload the data at least once a day. Clinicians downloaded the compliance data and communicated with the patients online based on their analysis of data at least once every 3 months. The measured force, quality compliance (measured force / baseline force), measured time, and quantity compliance (measured time/ prescribed time) were used to evaluate patient compliance. Patients were also asked to rate their satisfaction at the final follow-up.
Twenty-eight patients were included in the final analysis. The mean baseline force was 1.23 ± 0.28 N. The mean measured force was 0.79 ± 0.29 N. The mean quality compliance was 64.8 ± 22.2%. The prescribed time of all patients was 23 h. The mean measured time was 14.1 ± 2.9 h. The mean quantity compliance was 61.3 ± 12.6%. Both the quality and quantity compliance during the first 3 months of treatment was significantly lower than the latter 3 months. In this study, 96.4% (27/28) patients were satisfied with the use of the monitoring system, among whom 21.4% (6/28) are very satisfied and 75.0% (21/28) are somewhat satisfied.
The compliance real-time monitoring system, without evaluating the clinical and radiographic outcomes for now, has already shown some feasibility and effectiveness for the management of the brace usage in AIS patients. This system, as a useful tool for online patient management and patient-clinician communication, would be potentially employed on a large scale in future for clinicians to improve the compliance and satisfaction of AIS patients who have received brace treatment.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Metabolic syndrome (MetS) is associated with poor prognosis in many cancers. However, the relationship between metabolic syndrome and overall survival (OS) in patients with colorectal cancer (CRC) ...remains unclear. We aimed to comprehensively analyze whether MetS could affect postoperative complications and long-term survival in patients with CRC.
We included patients who underwent CRC resection at our center between January 2016 and December 2018. Bias was reduced through propensity score matching analysis. Patients with CRC were divided into the MetS and non-MetS groups based on whether they had MetS. Univariate and multivariate analyses were used to identify risk factors affecting OS.
We included 268 patients; among them, 120 were included for further analysis after propensity score matching. There were no significant between-group differences in the clinicopathological features after matching. Compared with the non-MetS group, the MetS group had a shorter OS (P = 0.027); however, there was no significant between-group difference in postoperative complications. Multivariate analysis revealed that MetS (hazard ratio HR = 1.997, P = 0.042), tumor-node-metastasis stage (HR = 2.422, P = 0.003), and intestinal obstruction (HR = 2.761, P = 0.010) were independent risk factors for OS.
MetS affects the long-term survival of patients with CRC without affecting postoperative complications.
Little is known about herpesvirus and putative periodontopathic bacteria in maternal chronic periodontitis. The present case-control study aimed to explore the potential relationship between putative ...periodontopathic bacteria and herpesviruses in maternal chronic periodontitis.Saliva samples were collected from 36 pregnant women with chronic periodontitis (cases) and 36 pregnant women with healthy periodontal status (controls). Six putative periodontopathic bacteria (Porphyromonas gingivalis Pg, Aggregatibacer actinomycetemcomitans Aa, Fusobacterium nucleatum Fn, Prevotella intermedia Pi, Tannerella forsythia Tf, and Treponema denticola Td) and three herpesviruses (Epstein-Barr virus EBV, human cytomegalovirus HCMV, and herpes simplex virus HSV) were detected. Socio-demographic data and oral health related behaviors, and salivary estradiol and progesterone levels were also collected. The results showed no significant differences in socio-demographic background, oral health related behaviors, and salivary estradiol and progesterone levels between the two groups (all P > 0.05). The detection rates of included periodontopathic microorganisms were not significantly different between the two groups (all P > 0.05), but the coinfection rate of EBV and Pg was significantly higher in the case group than in the control group (P = 0.028). EBV and Pg coinfection may promote the development of chronic periodontitis among pregnant women.
This study aimed to evaluate the safety and feasibility of subaxial cervical pedicle screw (CPS) insertion by comparing the morphological parameters between developmental canal stenosis (DCS) and ...non-developmental canal stenosis (NDCS) patients.
A total of 120 Chinese patients who had undergone cervical spinal multiplanar CT imaging from September 2010 to December 2014 were included in this study. According to the Pavlov ratio (PR), participants were classified into a DCS group (PR < 0.82) and an NDCS group (PR ≥0.82). CT reconstruction images of the cervical pedicles from C3 to C7 were selected for further analysis, and detailed morphological parameters for subaxial CPS insertion including pedicle outer width (POW), tiny cervical pedicle (TCP), pedicle transverse angle (PTA), and range of safe angle (RSA) were measured and compared in these two groups.
A total of 600 images (1200 pedicles) from these 120 patients were measured. The POW in the DCS group was wider than that in the NDCS group at each level, while the number of TCPs in the DCS group was significantly less than that in the NDCS group at the C3, C4, and C5 vertebrae. There was no significant difference in PTA at any level between the two groups, however the RSA in the DCS group was greater than that in the NDCS group from C4 to C7.
Subaxial CPS for DCS patients may be safer and more feasible than that for NDCS patients. However, as the subaxial cervical pedicle is relatively small, CPS insertion is difficult and preoperative CT evaluation is recommended for both DCS and NDCS patients.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this study, we aimed at characterizing the structure and the anticoagulant activity of a polysaccharide fraction (AGP33) isolated from the gonads of Haliotis discus hannai Ino. AGP33 was extracted ...by enzymatic hydrolysis and purified by ion-exchange and gel-filtration chromatography. The backbone fraction of AGP33 (BAGP33), which appeared to contain of mannose, glucose and galactose, was prepared by partial acid hydrolysis. According to methylation and nuclear magnetic resonance (NMR) spectroscopy, the backbone of AGP33 was identified as mainly consisting of 1→3-linked, 1→4-linked, and 1→6-linked monosaccharides. AGP33 is a sulfated polysaccharide with sulfates occur at 3-O- and 4-O-positions. It prolonged thromboplastin time (APTT), thrombin time (TT) and prothrombin time (PT) compared to a saline control solution in a dosage-dependent manner. AGP33 exhibited an extension (p < 0.01) of APTT compared to the saline group at concentrations higher than 5 μg/mL. AGP33 exhibited higher anticoagulant activity than its desulfated product (AGP33-des) and BAGP33. The results showed that polysaccharide with higher molecular weight and sulfate content demonstrated greater anticoagulant activity.
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