Medial meniscus tears are most prevalent in type I ACL tears, while type I ACL tears only account for 8% of all ACL tears.

PURPOSE: This study aimed to assess the distribution of different anterior cruciate ligament (ACL) tear locations in different magnetic resonance imaging (MRI) planes, and to explore the relationships of ACL tear types with both meniscus injuries and bone bruising. METHODS: A retrospective study was performed in patients under 60 years old who underwent MRI scans in the sagittal and coronal oblique planes of the knee for ACL tears between 2014 and 2020. Patients with reports of chronic tears, partial tears, or prior surgeries were excluded. Tear locations were classified into five types, and the meniscus tear measurement variables included the presence of ramp, root, bucket-handle, and other types of tears. All injuries were confirmed by arthroscopy. Meanwhile, the presence and location of bone bruising were analysed and scored with the Whole-Organ Magnetic Resonance Imaging Score (WORMS) bone bruising subscale. RESULTS: A total of 291 patients were included. The prevalence rates of type I and type III injuries were 23/291 (7.9%) and 145/291 (49.8%) in the sagittal plane and 22/291 (7.6%) and 179/291 (61.5%) in the oblique coronal plane, respectively. The prevalence of medial meniscus tears with ACL tears was 126/291 (43.3%), while that of lateral meniscus tears with ACL tears was 77/291 (26.5%). The highest prevalence of medial meniscus injury with ACL tears was 15/22 (68.2%) for type I injuries. Bone bruises were located on the lateral femoral center in 125 patients (46%) and on the lateral tibia posterior in 132 patients (48%); the common areas of bone bruising were slightly correlated with type III ACL tears but not correlated with type I ACL tears. CONCLUSION: The plane in which an MRI scan is performed affects the classification of ACL tears. The tear type is associated with the prevalence of medial meniscus injuries, and medial meniscus tears are most prevalent in type I ACL tears. LEVEL OF EVIDENCE: IV.

Alteration in topological organization characteristics of gray matter covariance networks in patients with prediabetes. / ç³–å°¿ç— å‰æœŸæ‚£è€ ç°è´¨åå˜ç½‘ç»œæ‹“æ‰‘ç»„ç»‡ç‰¹æ€§çš„æ”¹å˜.

OBJECTIVES: Prediabetes is associated with an increased risk of cognitive impairment and neurodegenerative diseases. However, the exact mechanism of prediabetes-related brain diseases has not been fully elucidated. The brain structure of patients with prediabetes has been damaged to varying degrees, and these changes may affect the topological characteristics of large-scale brain networks. The structural covariance of connected gray matter has been demonstrated valuable in inferring large-scale structural brain networks. The alterations of gray matter structural covariance networks in prediabetes remain unclear. This study aims to examine the topological features and robustness of gray matter structural covariance networks in prediabetes. METHODS: A total of 48 subjects were enrolled in this study, including 23 patients with prediabetes (the PD group) and 25 age-and sex-matched healthy controls (the Ctr group). All subjects' high-resolution 3D T1 images of the brain were collected by a 3.0 Tesla MR machine. Mini-mental state examination was used to evaluate the cognitive status of each subject. We calculated the gray matter volume of 116 brain regions with automated anatomical labeling (AAL) template, and constructed gray matter structural covariance networks by thresholding interregional structural correlation matrices as well as graph theoretical analysis. The area under the curve (AUC) in conjunction with permutation testing was employed for testing the differences in network measures, which included small world parameter (Sigma), normalized clustering coefficient (Gamma), normalized path length (Lambda), global efficiency, characteristic path length, local efficiency, mean clustering coefficient, and network robustness parameters. RESULTS: The network in both groups followed small-world characteristics, showing that Sigma was greater than 1, the Lambda was much higher than 1, and Gamma was close to 1. Compared with the Ctr group, the network of the PD group showed increased Sigma, Lambda, and Gamma across a range of network sparsity. The Gamma of the PD group was significantly higher than that in the Ctr group in the network sparsity range of 0.12-0.16, but there was no difference between the 2 groups (all P>0.05). The grey matter network showed an increased characteristic path length and a decreased global efficiency in the PD group, but AUC analysis showed that there was no significant difference between groups (all P>0.05). For the network separation measures, the local efficiency and mean clustering coefficient of the gray matter network in the PD group were significantly increased and AUC analysis also confirmed it (P=0.001 and P=0.004, respectively). In addition, network robustness analysis showed that the grey matter network of the PD group was more vulnerable to random damage (P=0.001). CONCLUSIONS: The prediabetic gray matter network shows an increased average clustering coefficient and local efficiency, and is more vulnerable to random damage than the healthy control, suggesting that the topological characteristics of the prediabetes grey matter covariant network have changed (network separation enhanced and network robustness reduced), which may provide new insights into the brain damage relevant to the disease.

Combination of 3.0T magnetic resonance imaging T2 mapping with texture analysis for evaluating the degeneration of lumbar facet joints. / 3.0Tç£å ±æŒ¯æˆåƒT2 mappingè”åˆçº¹ç†åˆ†æžè¯„ä¼°è °æ¤Žå°å ³èŠ‚é€€å˜ç¨‹åº¦.

OBJECTIVES: Quantitative magnetic resonance imaging has been successfully applied to assess the status of cartilage biochemical components. This study aimed to investigate the performance of 3.0T magnetic resonance imaging T2 mapping combined with texture analysis for evaluating the early degeneration of lumbar facet joints. METHODS: A total of 38 patients (20 in the asymptomatic group and 18 in the symptomatic group) were enrolled. All patients underwent 3.0T magnetic resonance imaging conventional sequences, water excitation three-dimensional spoiled gradient echo sequence (3D-WATSc), and T2 mapping scans. The bilateral L4/5 and L5/S1 lumbar facet joints were morphological graded using the Weishaupt criteria, T2 values, and texture parameters derived from T2 mapping of cartilage. The Kruskal-Wallis H test was used to compare the differences of parameters among different groups. Multivariate logistic regression analysis was used to obtain the independent predictive factors for evaluating the early degeneration of lumbar facet joints. Receiver operating characteristic (ROC) curve was performed and the area under curve (AUC) was calculated. Spearman correlation analysis was used to evaluate the correlation of the independent predictors of cartilage T2 value and texture parameters with the subjects' Japanese Orthopedic Association (JOA) score or Visual Analogue Scale (VAS) score. RESULTS: A total of 148 facet joints were selected, including 70 in Weishaupt 0 (normal) group, 58 in Weishaupt 1 group, and 20 in Weishaupt 2-3 group. T2 value, entropy, and contrast increased significantly as the exacerbation of facet joint degeneration (all P<0.05), while the inverse difference moment, energy, and correlation decreased (all P<0.05). Entropy among different groups was significantly different (all P<0.05), and the differences of T2 value, contrast, inverse difference moment, and energy between Weishaupt 0 and Weishaupt 1 groups, or Weishaupt 0 and Weishaupt 2-3 groups were statistically significant (all P<0.05). Multivariate logistic regression analysis suggested that T2 value and inverse difference moment were the independent predictors for evaluating early degeneration of facet joints. The combination of T2 value with inverse difference moment achieved the best performance in distinguishing Weishaupt 0 from Weishaupt 1 (AUC=0.85), with sensitivity and specificity at 92.7% and 76.5%, respectively. In the symptom group, the cartilage T2 value combined inverse difference moment was positively correlated with JOA score (r=0.475, P<0.05) and VAS score (r=0.452, P<0.05). CONCLUSIONS: 3.0T magnetic resonance imaging T2 mapping combined with texture analysis is helpful to quantitatively evaluate the early degeneration of lumbar facet joints, in which the T2 value and inverse difference moment show an indicative significance．.

[Combination of prostate imaging reporting and data system with the apparent diffusion coefficient map for the diagnosis of peripheral zone prostate cancer].

OBJECTIVE: To explore the value of prostate imaging reporting and data system version 2 (PI-RADS V2) combined with quantitative parameters derived from apparent diffusion coefficient (ADC) map in the diagnosis of peripheral zone prostate cancer.
 Methods: A total of 50 patients who underwent prostate multiparametric MRI (mpMRI) with suspicious peripheral nodules were retrospectively enrolled, and all patients were biopsy-proven histologically. Two radiologists analyzed the position and category of peripheral zone lesions based on PI-RADS V2. Then 12 ADC quantitative parameters were calculated regarding each lesion on the ADC map by post-processing software. The lesions were divided into malignant group and benign group according to histopathological findings. The ADC quantitative parameters between groups were compared, and stepwise logistic regression analysis was used to build a discriminative model. Receiver operating characteristic (ROC) curve and decision curve analysis (DCA) were performed to evaluate the diagnostic power and clinical benefit.
 Results: Twenty-eight peripheral zone prostate malignant lesions and 25 benign lesions were obtained finally. The area under the ROC curve, sensitivity and specificity to differentiate peripheral zone prostate malignant from benign lesions were as follows: 0.803, 60.71%, 92.00% (PI-RADS V2 score), 0.857, 89.29%, 76.00% (ADC model), and 0.891, 71.43%, 92.00% (combined model), respectively. The discriminative power of the combined model was significantly improved compared with PI-RADS V2 score (P=0.012). The combined model had relatively optimal overall net benefit, which outperformed the PI-RADS V2 score when threshold probability varied in the range of 0.05-0.27 and 0.46-0.81.
 Conclusion: PI-RADS V2 combined with quantitative analysis of ADC map improve the power in discriminating peripheral zone prostate cancer from benign lesions, and the clinical benefit as well.

Proton Magnetic Resonance Spectroscopy-Detected Changes of Marrow Fat Content in a Rabbit Model of Osteoporosis Treated With Epigallocatechin-3-Gallate.

OBJECTIVE: The aim of this study was to longitudinally evaluate the changes in marrow fat content of ovariectomized (OVX) rabbits treated with epigallocatechin-3-gallate (EGCG) using proton magnetic resonance spectroscopy (H-MRS). METHODS: Thirty-six female New Zealand rabbits were equally divided into sham operation, OVX controls, and OVX treated with EGCG (intraperitoneally, 1.8 mg/kg) for 5 months. Marrow fat fraction by H-MRS and bone density by peripheral quantitative computed tomography were determined at 0, 3, and 5 months. Serum biomarkers and marrow adipocytes were determined at the end of experiment. RESULTS: Estrogen deficiency increased marrow fat content in a time-dependent manner, with a variation of marrow fat fraction (FF) (+25.3%) at month 3 from baseline, and it was maintained until month 5 (+66.6%, all P < 0.001). In comparison with the sham-operated controls, adipocytes density, size, and percentage of adipocytes area in the OVX controls increased by 62.9%, 44.4%, and 178%, respectively (all P < 0.05). These OVX-induced pathological changes were partly reversed by EGCG treatment. In addition, EGCG treatment reduced bone turnover and increased bone density of OVX rabbits. CONCLUSIONS: Epigallocatechin-3-gallate exhibits an anabolic effect on osteoporotic bone by concomitantly rescuing bone mass and mitigating marrow adiposity. H-MRS appears to be a useful tool for monitoring osteoporosis-related treatments.

[A cross-sectional study on the correlation between MRI signal for IPFP and knee osteoarthritis].

OBJECTIVE: To investigate the correlation between MRI signal for infrapatellar fat pad (IPFP) and pathological changes in knee osteoarthritis (KOA), and to analyze the role of IPFP in the development of knee osteoarthritis.
 Methods: A total of 114 subjects (without special knee disease) were enrolled for this study. The intensity of MRI signal for IPFP was determined by fat-suppressed proton-density-weighted turbospin-echo magnetic resonance imaging. Based on the cartilage defects and osteophytes of knee joint, the subjects were divided into a KOA group and a control group. The difference of MRI signal for IPFP between two groups was analyzed.
 Results: After excluding the potential confounders of age, gender and BMI, the intensity of MRI signal for IPFP was positively correlated with defections in patellar, medial femur, lateral tibial or knee joint (OR 1.333 to 2.168, P 0.006 to 0.023); the intensity of MRI signal for IPFP was also positively correlated with osteophytes in patellar, medial femur, lateral tibial or knee joint (OR 1.309 to1.781, P 0.004 to 0.046); the intensity of MRI signal for IPFP in the KOA group was significantly higher than that in the control group (P=0.028).
 Conclusion: The increase in the density of MRI signal for IPFP is an imaging manifestation for knee degeneration. IPFP inflammation and endocrine abnormalities may play an important role in KOA.

An innovative method based on Gaussian cloud distribution and sample information richness for eutrophication assessment of Yangtze's lakes and reservoirs under uncertainty.

The precise assessment of a water body's eutrophication status is essential for making informed decisions in water environment management. However, conventional approaches frequently fail to consider the randomness, fuzziness, and inherent hidden information of water quality indicators. These would result in an unreliable assessment. An enhanced method was proposed for the eutrophication assessment under uncertainty in this study. The multi-dimension gaussian cloud distribution was introduced to capture the randomness and fuzziness. The Shannon entropy based on various sample size and trophic levels was proposed to maximize valuable information hidden in the datasets. Twenty-seven significant lakes and reservoirs located in the Yangtze River Basin were selected to demonstrate the proposed method. The sensitivity and consistency were used to evaluate the accuracy of the proposed method. Results indicate that the proposed method has the capability to effectively assess the eutrophication status of lakes and reservoirs under uncertainty and that it has a better sensitivity since it can identify more than 33-50% trophic levels compared to the traditional methods. Further scenario experiments analysis revealed that the sample information richness, i.e., sample size and the number of trophic levels is of great significance to the accuracy/robustness of the method. Moreover, a sample size of 60 can offer the most favorable balance between accuracy/robustness and the monitoring expenses. These findings are crucial to optimizing the eutrophication assessment.

An injectable, chitosan-based hydrogel prepared by Schiff base reaction for anti-bacterial and sustained release applications.

Injectable hydrogels, providing sustained release as implanted materials, have received tremendous attention. In this study, chitosan-based hydrogels were prepared via Schiff base reaction of the aldehyde groups on Poly(NIPAM-co-FBEMA) and the amine groups on chitosan. Owing to the dynamic covalent linkage, the SC/PNF hydrogels exhibit pH-responsive, reversible sol-gel transition, injectable, and self-healing capacity. The mechanical strength of SC/PNF hydrogels can be operated simply by switching the composition or solid content of Poly(NIPAM-co-FBEMA) copolymers. Rheological analyses, including frequency sweeps, strain sweep scanning, and dynamic time sweeps, were employed to demonstrate the relationship between storage modulus (G'), loss modulus (G″), and composition of the SC/PNF hydrogels. In vitro release behaviors reveal that vancomycin-loaded SC/PNF hydrogel could contribute to both the initial burst release (over 1000 ppm within 4 h) and the sustained release (3000 ppm for at least 30 days). Pristine SC/PNF hydrogel holds good biocompatibility toward L929 cells and S. aureus that it degrades as incubated with S. aureus. However, vancomycin-wrapped SC/PNF hydrogel possesses a rapid bacterial-killing effect with a clear inhibition zone. In short, the SC/PNF hydrogels deliver not only sustainable release ability but also tunable physical properties, which are expected to be an outstanding candidate for non-invasive, anti-infection applications.

High-resolution oblique coronal MRI at optimal flexed-knee angle: a novel imaging method for enhanced anterior cruciate ligament tear diagnosis.

BACKGROUND: The accuracy of traditional knee MR imaging in diagnosing anterior cruciate ligament tears, especially partial tears, is relatively low, which may lead to misdiagnosis and missed diagnosis. This study aimed to assess the diagnostic performance of a novel imaging method, high-resolution oblique coronal MRI at an optimal flexed-knee Angle, for ACL tears. METHODS: 50 healthy volunteers were scanned with a scan-assisted device for the optimal flexion angle of ACL. For 92 knee trauma patients selected strictly according to inclusion and exclusion criteria, conventional extended-knee scans (control group) and high-resolution oblique coronal scans based on the optimal flexed-knee angle (experimental group) were conducted. Two observers rated ACL visibility blindly on a 5-point scale. Arthroscopy-defined outcomes determined diagnostic metrics for each method and sensitivity, specificity, positive predictive value, negative predictive value and accuracy were calculated. RESULTS: The average optimal flexion angle for healthy volunteers was approximately 30° (30.3° ± 5.0°). Imaging demonstrated complete visualization of the ACL in 96.7% of images in the experimental group versus 12.0% in the control group. The diagnostic indicators of the experimental group surpassed those of the control group: sensitivity (94.9% vs. 76.3%), specificity (97.0% vs. 81.8%), positive predictive value (98.2% vs. 88.2%), negative predictive value(91.4% vs. 65.9%), and accuracy (95.7% vs. 78.3%). ROC analysis indicated superior diagnostic performance in the experimental group, with an AUC of 0.945 compared with 0.776 for the control group (p < 0.0001). CONCLUSIONS: High-resolution oblique coronal imaging at the optimal 30° flexed-knee angle improved ACL visualization and diagnostic performance compared with conventional techniques.

Topological abnormality of structural covariance network in MRI-negative frontal lobe epilepsy.

Background: Frontal lobe epilepsy (FLE) is the second most common type of focal epilepsy, however, imaging studies of FLE have been far less than Temporal lobe epilepsy (TLE) and the structural findings were not consistent in previous literature. Object: Investigate the changes in cortical thickness in patients with FLE and the alteration of the structural covariance networks (SCNs) of cortical thickness with graph-theory. Method: Thirty patients with FLE (18 males/12 females; 28.33 ± 11.81 years) and 27 demographically matched controls (15 males/12 females; 29.22 ± 9.73 years) were included in this study with high-resolution structural brain MRI scans. The cortical thickness was calculated, and structural covariance network (SCN) of cortical thickness were reconstructed using 68 × 68 matrix and analyzed with graph-theory approach. Result: Cortical thickness was not significantly different between two groups, but path length and node betweenness were significantly increased in patients with FLE, and the regional network alterations were significantly changed in right precentral gyrus and right temporal pole (FDR corrected, p < 0.05). Comparing to HC group, network hubs were decreased and shifted away from frontal lobe. Conclusion: The topological properties of cortical thickness covariance network were significantly altered in patients with FLE, even without obvious surface-based morphological damage. Graph-theory based SCN analysis may provide sensitive neuroanatomical biomarkers for FLE.

Effect of laparoscopic sleeve gastrectomy on mobilization of site-specific body adipose depots: a prospective cohort study.

BACKGROUND: Effect of bariatric surgery on mobilization of site-specific body adipose depots is not well investigated. Herein, the authors conducted a prospective cohort study to assess whether bariatric surgery can differentially affect specific fat storage pools and to further investigate correlations between site-specific fat mobilization and clinical outcomes. MATERIALS AND METHODS: In this single-centre prospective cohort study, 49 participants underwent laparoscopic sleeve gastrectomy (LSG) from 24 May 2022 to 20 October 2022 and underwent MRI to estimate subcutaneous fat area, visceral fat area (VFA), hepatic and pancreatic proton density fat fraction (PDFF) at baseline and 3 months after surgery. The protocol for this study was registered on clinicaltrials.gov. RESULTS: Among 49 patients who met all inclusion criteria, the median [interquartile range (IQR)] age was 31.0 (23.0-37.0) years, the median (IQR) BMI was 38.1 (33.7-42.2) kg/m 2 and 36.7% were male. Median (IQR) percentage hepatic PDFF loss was the greatest after bariatric surgery at 68.8% (47.3-79.7%), followed by percentage pancreatic PDFF loss at 51.2% (37.0-62.1%), percentage VFA loss at 36.0% (30.0-42.4%), and percentage subcutaneous fat area loss at 22.7% (17.2-32.4%) ( P <0.001). By calculating Pearson correlation coefficient and partial correlation coefficient, the positive correlations were confirmed between change in VFA and change in glycated haemoglobin ( r =0.394, P =0.028; partial r =0.428, P =0.042) and between change in hepatic PDFF and change in homoeostatic model assessment of insulin resistance ( r =0.385, P =0.025; partial r =0.403, P =0.046). CONCLUSIONS: LSG preferentially mobilized hepatic fat, followed by pancreatic fat and visceral adipose tissue, while subcutaneous adipose tissue was mobilized to the least extent. Reduction in visceral adipose tissue and hepatic fat is independently associated with the improvement of glucose metabolism after LSG.

Evaluation of the efficacy of transcatheter arterial embolization combined with apatinib on rabbit VX2 liver tumors by intravoxel incoherent motion diffusion-weighted MR imaging.

Background and purpose: It is crucial to evaluate the efficacy, recurrence, and metastasis of liver tumors after clinical treatment. This study aimed to investigate the value of Introvoxel Incoherent Motion (IVIM) imaging in the evaluation of rabbit VX2 liver tumors treated with Transcatheter Arterial Embolization (TAE) combined with apatinib. Methods: Twenty rabbit VX2 liver tumor models were established and randomly divided into either the experimental group (n=15) or the control group (n=5). The experimental group was treated with TAE combined with oral apatinib after successful tumor inoculation, while no treatment was administered following inoculation in the control group. IVIM sequence scan was performed in the experimental group before treatment, at 7 and 14 days after treatment. All rabbits were sacrificed after the last scan of the experimental group. Marginal tissues from the tumors of both groups were excised for immunohistochemical analysis to observe and compare the expression of microvessel density (MVD). The alterations of IVIM-related parameters of tumor tissues in the experimental group, including Apparent Diffusion Coefficient (ADC), True Diffusion Coefficient (D), Pseudodiffusion Coefficient (D*), and Perfusion Fraction (f) were compared at different periods, and the correlation between these parameters and MVD was analyzed. Results: After treatment, ADC and D values significantly increased, whereas D* and f values both decreased, with statistically significant differences.(P<0.05). The average tumor MVD of the experimental group after TAE combined with apatinib ((33.750 ± 6.743) bars/high power field (HPF)) was significantly lower than that in the control group ((64.200 ± 10.164) bars/HPF)). Moreover, D and f were positively correlated with tumor MVD in the experimental group (r=0.741 for D and r=0.668 for f, P<0.05). However, there was no significant correlation between ADC and D* values of the experimental group and tumor MVD (r=0.252 for ADC and r=0.198 for D*, P>0.05). Conclusion: IVIM imaging can be employed to evaluate the efficacy of TAE combined with apatinib in rabbit VX2 liver tumors. Alterations in D and f values were closely related to the MVD of liver tumor tissues.

Increased signal intensity, not volume variation of infrapatellar fat pad in knee osteoarthritis: A cross-sectional study based on high-resolution magnetic resonance imaging.

BACKGROUND: Infrapatellar fat pad (IPFP) is regarded as an essential knee tissue involved in osteoarthritis (OA) for its potential structural-related or metabolism-related function. This cross-sectional study aims to identify which part is more related to OA. METHODS: Patients with knee OA (n = 53) and healthy controls (n = 54) were prospectively recruited. Based on high-resolution magnetic resonance imaging with a slice thickness of only 0.35 mm, IPFP structural-related parameters (volume and maximal area), metabolism-related parameter (signal), degeneration indicators, and patellar maltracking indicators (patellar translation, patellofemoral angle, and Insall-Salvati ratio) were measured. IPFP volume (maximal area, and signal) was compared between healthy controls and OA patients. The level of significance for all comparisons was set as .05. RESULTS: OA patients had higher IPFP signal (672.9 ± 136.9 vs 567.3 ± 63.6, p = .009), but no significant difference in IPFP volume or maximal area compared with healthy controls. In healthy controls, IPFP signal was positively associated with age (ß = 1.481; 95% CI: 0.286-2.676; p = .018); IPFP maximal area was positively related to Insall-Salvati ratio (ß = 0.001; 95% CI: 0.0003-0.0017; p = .039), but not associated with patellar translation and patellofemoral angle. In OA patients, IPFP signal was positively associated with cartilage loss (ß = 0.005; 95% CI: 0.003-0.007; p = .013); no correlation between knee pain and IPFP volume or maximal area was observed. CONCLUSIONS: The metabolism-related function of IPFP, which can be reflected by the IPFP signal, might play a more critical role in OA progression than its structural function.

Biomechanical influence of T1 tilt alteration on adjacent segments after anterior cervical fusion.

Background: Anterior cervical fusion (ACF) has become a standard treatment approach to effectively alleviate symptoms in patients with cervical spondylotic myelopathy and radiculopathy. However, alteration of cervical sagittal alignment may accelerate degeneration at segments adjacent to the fusion and thereby compromise the surgical outcome. It remains unknown whether changes in T1 tilt, an important parameter of cervical sagittal alignment, may cause redistribution of biomechanical loading on adjacent segments after ACF surgery. Objective: The objective was to examine the effects of T1 tilt angles on biomechanical responses (i.e.range of motion (ROM) and intradiscal VonMises stress) of the cervical spine before and after ACF. Methods: C2-T1 FE models for pre- and postoperative C4-C6 fusion were constructed on the basis of our previous work. Varying T1 tilts of -10°, -5°, 0°, 5°, and 10° were modeled with an imposed flexion-extension rotation at the T1 inferior endplate for the C2-T1 models. The flexion-extension ROM and intradiscal VonMises stress of functional spinal units were compared between the pre- and postoperative C2-T1 FE models of different T1 tilts. Results: The spinal segments adjacent to ACF demonstrated higher ROM ratios after the operation regardless of T1 tilt. The segmental ROM ratio distribution was influenced as T1 tilt varied and loading conditions, which were more obvious during displacement-control loading of extension. Regardless of T1 tilt, intradiscal VonMises stress was greatly increased at the adjacent segments after the operation. As T1 tilt increased, intradiscal stress at C3-C4 decreased under 30° flexion and increased under 15° extension. The contrary trend was observed at the C6-C7 segment, where the intradiscal stress increased with the increasing T1 tilt under 30° flexion and decreased under 15° extension. Conclusion: T1 tilt change may change biomechanical loadings of cervical spine segments, especially of the adjacent segments after ACF. Extension may be more susceptible to T1 tilt change.

Engineering an enthesis-like graft for rotator cuff repair: An approach to fabricate highly biomimetic scaffold capable of zone-specifically releasing stem cell differentiation inducers.

Rotator cuff (RC) attaches to humerus across a triphasic yet continuous tissue zones (bone-fibrocartilage-tendon), termed "enthesis". Regrettably, rapid and functional enthesis regeneration is challenging after RC tear. The existing grafts bioengineered for RC repair are insufficient, as they were engineered by a scaffold that did not mimic normal enthesis in morphology, composition, and tensile property, meanwhile cannot simultaneously stimulate the formation of bone-fibrocartilage-tendon tissues. Herein, an optimized decellularization approach based on a vacuum aspiration device (VAD) was developed to fabricate a book-shaped decellularized enthesis matrix (O-BDEM). Then, three recombinant growth factors (CBP-GFs) capable of binding collagen were synthesized by fusing a collagen-binding peptide (CBP) into the N-terminal of BMP-2, TGF-ß3, or GDF-7, and zone-specifically tethered to the collagen of O-BDEM to fabricate a novel scaffold (CBP-GFs/O-BDEM) satisfying the above-mentioned requirements. After ensuring the low immunogenicity of CBP-GFs/O-BDEM by a novel single-cell mass cytometry in a mouse model, we interleaved urine-derived stem cell-sheets into this CBP-GFs/O-BDEM to bioengineer an enthesis-like graft. Its high-performance on regenerating enthesis was determined in a canine model. These findings indicate this CBP-GFs/O-BDEM may be an excellent scaffold for constructing enthesis-like graft to patch large/massive RC tears, and provide breakthroughs in fabricating graded interfacial tissue.

Magnetic resonance spectroscopy of the cerebellum in patients with spinocerebellar ataxia type 3/Machado-Joseph disease.

OBJECTIVE: To evaluate the metabolite pattern and the severity in patients with spinocerebellar ataxia type 3/ Machado-Joseph disease (SCA3/MJD) by (1)H magnetic resonance spectroscopy ((1)H-MRS) on different cerebellar regions, including cerebellar vermis, cerebellar peduncles, cerebellar cortex, and dentatum. METHODS: Thirty-six SCA3/MJD patients, and 27 sex, age-matched healthy controls were scanned with (1)H-MRS for N-acetylaspartate (NAA), choline (Cho) and creatine (Cr). We made cerebellar vermis, cerebellar peduncles, cerebellar cortex, and dentatum as the region of interests (ROI), and finally got access to NAA/Cr, Cho/Cr, and NAA/Cho ratios. We also examined the CAG repeat numbers of MJD1 gene, scored the 36 patients by the scale for the assessment and rating of ataxia (SARA), analyzed the differences in ratios between SCA3/MJD patients and the control group, and explored whether relevance existed between these ratios and duration of the disease, age of onset, CAG repeat times, and SARA scores respectively. RESULTS: The ratio of NAA/Cr in SCA3/MJD patients showed a significant reduction in the cerebellar cortex, dentatum, cerebellar vermis and medipeduncle (P<0.01) compared with the controls. The ratio of NAA/Cho also showed significant reduction in the dentatum and cerebellar vermis (P<0.01). A number of correlations were found between the metabolite ratios of (1)H-MRS and duration of the disease, age of onset, expanded CAG and SARA score in SCA3/MJD patients. CONCLUSION: (1)H-MRS, which shows the neural metabolic changes in the cerebella of SCA3/MJD patients, provides useful information about the severity of SCA3/MJD.

Homotopy of resting-state functional connectivity correlates with psychological distress in adolescent and young adult cancer patients.

BACKGROUND: Adolescent and young adult cancer patients (AYACPs) experience a high incidence of psychological distress. However, the effect of psychological distress on the functional connectivity between the hemispheres in AYACPs remains unknown. Voxel-mirrored homotopy connectivity detection is an effective way to explore the effects of psychological distress on functional connectivity throughout the brain in AYACPs. METHODS: Twenty-four AYACPs underwent structural magnetic resonance imaging. RESULTS: Voxel-mirrored homotopy connectivity in the psychological distress group was significantly lower in the superior parietal gyrus, middle frontal gyrus (orbital part), superior frontal gyrus (dorsolateral), superior occipital gyrus, precuneus, lingual gyrus, calcarine fissure and surrounding cortex than in the non-psychological distress group, while in the inferior temporal gyrus and middle frontal gyrus (orbital part), voxel-mirrored homotopy connectivity was significantly higher (p < 0.05). ROC curve analysis showed that the decrease in voxel-mirrored homotopy connectivity in the following brain regions was helpful in distinguishing the psychological distress group from the non-psychological distress group: left superior frontal gyrus (dorsolateral), left calcarine fissure and surrounding cortex, right postcentral gyrus, and left precuneus. CONCLUSIONS: Activity imbalances in multiple brain regions exist in AYACPs with psychological distress. Voxel-mirrored homotopy connectivity detection is an effective way to explore the potential neural mechanisms of mental disorders in AYACPs and optimize the treatment of mental disorders.

[Influence of Impervious Surface Roughness on Accumulation and Erosion of Urban Non-Point Source Particles].

At present, there are few reports about how impervious surface microstructure characteristics affect the runoff output process of street dust. Based on field observations of 12 rainfall events, this study quantified the microstructure characteristics of impervious surfaces by structural depth (roughness) and analyzed the correlation between roughness and accumulation characteristics of street dust on sunny days as well as scouring characteristics in rainy days. The results show that the roughness of the underlying surface notably affects dust accumulation on sunny days and scouring in rainy days. The correlation between roughness and street dust accumulation (r=0.664, P<0.01) was enhanced on sunny days, and the correlation between roughness and street dust erosion (r=0.527, P<0.01) was enhanced by rainfall. The correlation of street dust accumulation and roughness of each particle size segment increased as particle size increased (0.529 ≤ r<0.757), and the correlation between street dust scouring amount and roughness decreased as particle size increased (0.603 > R > 0.209). By establishing the linear regression model of roughness and rainfall, the cumulative pollution load of TSS in rainfall runoff can be well predicted. The effects of roughness and rainfall on the cumulative load of grain sizes<20 µm and >250 µm are significant. These results elucidate the role of roughness and rainfall analysis in predicting surface runoff pollution load characteristics, which can provide new information for predicting and evaluating urban non-point source pollution.

[Comparison between pig lumbar zypapophyseal joint cartilage acquired from multiple magnetic resonance image sequences and gross specimens].

OBJECTIVE: To evaluate the capability and limitation of magnetic resonance image(MRI)for Lumbar zygapophyseal joint cartilage through comparing pig lumbar zygapophyseal joint cartilage acquired from multiple MRI sequences of a 1.5 Tesla MR and gross specimens. METHODS: Six fresh lumbar spines from adult pigs were sagittaly scanned by Siemens 1.5 Tesla MR. The scan sequences included fast spin echo T1-weighted imaging (FSE T1WI), fast spin echo T2-weighted imaging (FSE T2 weighted T2WI), fat saturation proton density-weighted imaging (FS PDWI), 3-dimensional fast low angle shot imaging (3D-FLASH), and water excitation 3-dimensional fast low angle shot imaging (WE 3D-FLASH). Each scan sequence acquired images from the same layer. The signal-noise ratio (SNR) for articular cartilage, contrast-noise ratio (CNR) for cartilage versus bone cortex, cartilage versus bone marrow, and cartilage versus saline were calculated. Right after the scanning, the lumbar spines were snap-frozen, incised sagittally along the midline lumbar zypapophyseal joints, and photographed to compare the gross specimens with corresponding MRIs. The thickness of sagittal midline center of 6 pairs of lumbar(L3/L4) zypapophyseal joint cartilage was measured by vernier caliper. The thickness of the back ventral articular cartilage was added and then compared with corresponding MR images. RESULTS: 3D-FLASH (FA 20°) and WE 3D-FLASH (FA 20°) sequences had significant advantages compared with other sequences in imaging lumbar zypapophyseal joint cartilage, and were mostly close to the real thickness.(1) Comparison of the 4 flip angle (FA 10°, FA 20°, FA 30°, and FA 40°) 3D-FLASH sequences:The highest cartilage SNR and best CNR of cartilage versus bone cortex were both found in the 3D-FLASH(FA 20°) sequence, which was significantly different from the other three 3D-FLASH sequences.The satisfactory CNR of cartilage versus bone marrow, cartilage versus saline were found more in the 3D-FLASH(FA 20°) sequence. (2) Comparison of the 4 flip angle(FA 10°, FA 20°, FA 30°, and FA 40°) WE 3D-FLASH sequences: the highest cartilage SNR,best CNR of cartilage versus bone cortex,and best CNR of cartilage versus bone marrow were found in the WE 3D-FLASH (FA 20°) sequence, which was significantly different from the other three 3D-FLASH sequences. The CNR of cartilage versus saline was found more satisfactory in the WE 3D-FLASH (FA 20°) sequence. (3) The highest cartilage SNR and best CNR of cartilage versus bone cortex were both found in the 3D-FLASH (FA 20°) sequence, which was significantly different from those in the PDWI, FSE T1WI,and FSE T2WI sequences (P<0.05), but with no significance (P>0.05) in the WE 3D-FLASH (FA 20°) sequence. The highest CNR of cartilage versus bone marrow was seen in WE 3D-FLASH (FA 20°) sequence. It was statistically significant compared with that in FS PDWI,FSE T1WI, and T2WI sequences respectively, but the difference was not significant compared with 3D-FLASH (FA 20°) sequence (P>0.05). Both the FS PDWI and T2WI sequences displayed ideal CNR of cartilage versus saline, with no significant difference (P>0.05). The lower SNR of cartilage versus saline was shown in 3D-FLASH (FA 20°) and WE 3D-FLASH (FA 20°) sequence, and the difference was not significant (P>0.05). However, they were significantly different compared with FS PDWI and T2WI sequences (P<0.05). (4) WE 3D-FLASH (FA 20°) and 3D-FLASH (FA 20°) sequences were relatively better than the FS PDWI when comparing the thickness of articular cartilage, which was significantly different from the FS PDWI sequence (P<0.05). CONCLUSION: The 3D-FLASH sequence and derived WE 3D-FLASH sequence have better definition of cartilage images and are mostly close to the real thickness, which possibly are the optimal scanning sequences for lumbar zypapophyseal joint articular cartilage MR imaging.

Computational Modeling of Fructose Metabolism and Development in NAFLD.

Non-alcohol fatty liver disease (NAFLD) is a common disorder that has increased in prevalence 20-fold over the last three decades. It covers a spectrum of conditions resulting from excess lipid accumulation in the liver without alcohol abuse. Among all the risk factors, over-consumption of fructose has been repeatedly reported in both clinical and experimental studies to be highly associated with the development of NAFLD. However, studying in vivo systems is complicated, time consuming and expensive. A detailed kinetic model of fructose metabolism was constructed to investigate the metabolic mechanisms whereby fructose consumption can induce dyslipidaemia associated with NAFLD and to explore whether the pathological conditions can be reversed during the early stages of disease. The model contains biochemical components and reactions identified from the literature, including ~120 parameters, 25 variables, and 25 first order differential equations. Three scenarios were presented to demonstrate the behavior of the model. Scenario one predicts the acute effects of a change in carbohydrate input in lipid profiles. The results present progressive triglyceride accumulations in the liver and plasma for three diets. The rate of accumulation was greater in the fructose diet than that of the mixed or glucose only models. Scenario two explores the variability of metabolic reaction rate within the general population. Sensitivity analysis reveals that hepatic triglyceride concentration is most sensitive to the rate constant of pyruvate kinase and fructokinase. Scenario three tests the effect of one specific inhibitor that might be potentially administered. The simulations of fructokinase suppression provide a good model for potentially reversing simple steatosis induced by high fructose consumption, which can be corroborated by experimental studies. The predictions in these three scenarios suggest that the model is robust and it has sufficient detail to present the kinetic relationship between fructose and lipid in the liver.