Three-dimensional analysis

三维分析
  • 文章类型: Journal Article
    背景:旨在测量和比较患有HFM和孤立性小耳症的患者面部硬软组织的不对称性,研究它是如何演变的。
    方法:这项横断面研究评估了5-12岁的男性东亚患者的面部不对称性,这些患者被诊断为单侧半面微缩肌(Pruzansky-KabanI型和IIA型)或孤立的微缩肌。使用计算机断层扫描的3D成像,它测量了面部区域表面偏差的均方根(RMS)值。统计分析探讨了条件之间的差异以及年龄与面部不对称的关系。
    结果:共有120名患者按病情(HFM或孤立的小耳畸形)和年龄(5-7岁和8-12岁)分为四组。HFM患者在下脸颊表现出最大的不对称性,而那些孤立的小骨症主要表现为上表面不对称。显著差异,除了前额和鼻软组织,在不同年龄类别的组间进行了记录。HFM患者的鼻腔和中颊区域的年龄组之间在硬组织中发现了明显的差异(中位数RMS(mm)0.9与1.1,P=0.02;1.5vs.1.7,P=0.03),并且在孤立性小耳畸形患者的鼻和上唇区域(中位数RMS(mm)0.8vs.0.9,P=0.002;0.8vs.1.0,P=0.002)。除了HFM的这些领域,未检测到显著的年龄不对称相关性.
    结论:在HFM和孤立的小耳之间观察到面部不对称的显着差异,特定区域的不对称性随着时间的推移而演变。
    方法:本期刊要求作者为每篇文章分配一定程度的证据。对于这些循证医学评级的完整描述,请参阅目录或在线作者说明www。springer.com/00266.
    BACKGROUND: Aiming to measure and compare asymmetry of facial hard and soft tissues in patients with HFM and isolated microtia, examining how it evolves.
    METHODS: This cross-sectional study assessed facial asymmetry in male East Asian patients aged 5-12 diagnosed with unilateral hemifacial microsomia (Pruzansky-Kaban types I and IIA) or isolated microtia. Using 3D imaging of computed tomography scans, it measured root-mean-square (RMS) values for surface deviations across facial regions. Statistical analyses explored differences between conditions and the relationship of age with facial asymmetry.
    RESULTS: A total of 120 patients were categorized into four groups by condition (HFM or isolated microtia) and age (5-7 and 8-12 years). Patients with HFM exhibited the greatest asymmetry in the lower cheek, while those with isolated microtia showed primarily upper face asymmetry. Significant differences, except in the forehead and nasal soft tissue, were noted between the groups across age categories. Notable distinctions in hard tissue were found between age groups in the nasal and mid-cheek areas for patients with HFM (median RMS (mm) 0.9 vs. 1.1, P = 0.02; 1.5 vs. 1.7, P = 0.03) and in the nasal and upper lip areas for patients with isolated microtia (median RMS (mm) 0.8 vs. 0.9, P = 0.002; 0.8 vs. 1.0, P = 0.002). Besides these areas for HFM, no significant age-asymmetry correlation was detected.
    CONCLUSIONS: Significant differences in facial asymmetry were observed between HFM and isolated microtia, with the asymmetry in specific area evolving over time.
    METHODS: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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  • 文章类型: Journal Article
    本研究旨在探讨颞下颌关节(TMJ)积液与TMJ疼痛之间的关系,以及通过二维(2D)和三维(3D)磁共振成像(MRI)评估患者的颌骨功能限制。
    121例被诊断为颞下颌关节紊乱病(TMD)的患者被纳入。使用MRI定性评估TMJ积液,并使用3DSlicer软件定量。然后相应地分级。此外,采用视觉模拟量表(VAS)进行疼痛报告,采用8项颌骨功能限制量表(JFLS-8)评估颌骨功能限制.适当地进行统计分析以进行组比较和关联确定。P<0.05的概率被认为是统计学上显著的。
    2D定性和3D定量策略对于TMJ积液等级(κ=0.766)是高度一致的。关节积液与颞下颌关节疼痛无显著关联,也没有椎间盘位移和JLFS-8评分。此外,二元logistic回归分析显示性别与TMJ积液的存在显著相关,女性的赔率为5.168(p=0.008)。
    2D定性评估与3D定量评估对TMJ积液的诊断同样有效。在TMJ积液和TMJ疼痛之间没有发现显着关联。椎间盘位移或钳口功能限制。然而,研究表明,女性TMD患者可能存在TMJ积液的风险.需要进一步的前瞻性研究进行验证。
    UNASSIGNED: This study aimed to investigate the relationship between temporomandibular joint (TMJ) effusion and TMJ pain, as well as jaw function limitation in patients via two-dimensional (2D) and three-dimensional (3D) magnetic resonance imaging (MRI) evaluation.
    UNASSIGNED: 121 patients diagnosed with temporomandibular disorder (TMD) were included. TMJ effusion was assessed qualitatively using MRI and quantified with 3D Slicer software, then graded accordingly. In addition, a visual analogue scale (VAS) was employed for pain reporting and an 8-item Jaw Functional Limitations Scale (JFLS-8) was utilized to evaluate jaw function limitation. Statistical analyses were performed appropriately for group comparisons and association determination. A probability of p<0.05 was considered statistically significant.
    UNASSIGNED: 2D qualitative and 3D quantitative strategies were in high agreement for TMJ effusion grades (κ = 0.766). No significant associations were found between joint effusion and TMJ pain, nor with disc displacement and JLFS-8 scores. Moreover, the binary logistic regression analysis showed significant association between sex and the presence of TMJ effusion, exhibiting an Odds Ratio of 5.168 for females (p = 0.008).
    UNASSIGNED: 2D qualitative evaluation was as effective as 3D quantitative assessment for TMJ effusion diagnosis. No significant associations were found between TMJ effusion and TMJ pain, disc displacement or jaw function limitation. However, it was suggested that female patients suffering from TMD may be at a risk for TMJ effusion. Further prospective research is needed for validation.
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  • 文章类型: Journal Article
    目的:对平均年龄为5岁的单侧唇腭裂手术(UCLP)患者的颅颌面骨骼发育差异进行三维评估。
    方法:分析了30例接受PNAM的UCLP患者和34例未接受PNAM的UCLP患者的锥形束CT照片。数据以DICOM文件格式存储,并导入到海豚成像程序中进行3D图像重建和地标识别。33个地标,通过使用Mann-WhitneyU检验,对代表颅面形态的17个线性变量和三个角度变量进行了分析和比较。
    结果:反映颅面骨骼对称性的标志点的绝大多数线性变量和3D坐标在两组之间没有显着差异。在颅面骨骼发育方面,与非PNAM组相比,PNAM组的正中矢状面前鼻棘偏移明显较小,上颌长度较大.
    结论:在儿童早期进行的评估表明,在新生儿期使用/不使用PNAM治疗不是影响UCLP患者颅颌面硬组织发育的主要因素;此外,PNAM治疗显示明显纠正了鼻子底部的骨骼偏差。
    结论:在儿童早期的随访表明,在新生儿期进行的PNAM治疗不会阻碍上颌发育,并且在纠正鼻底偏曲方面具有益处。这是改善单侧唇腭裂患儿鼻畸形的可行选择。
    OBJECTIVE: To three-dimensionally assess differences in craniomaxillofacial skeletal development in patients with operated unilateral cleft lip and palate (UCLP) treated with/without presurgical nasoalveolar molding (PNAM) with a mean age of 5 years.
    METHODS: Cone-beam CT radiographs of 30 patients with UCLP who had undergone PNAM and 34 patients with UCLP who did not receive PNAM were analyzed. The data were stored in DICOM file format and were imported into the Dolphin Imaging program for 3D image reconstruction and landmark identification. 33 landmarks, 17 linear and three angular variables representing craniofacial morphology were analyzed and compared by using the Mann-Whitney U tests.
    RESULTS: The vast majority of linear variables and 3D coordinates of landmark points reflecting craniofacial skeletal symmetry were not significantly different between the two groups. In terms of craniofacial skeletal development, the PNAM group had a significantly smaller anterior nasal spine offset in the midsagittal plane and a greater maxillary length compared to the non-PNAM group.
    CONCLUSIONS: Evaluations performed in early childhood showed that treatment with/without PNAM in the neonatal period was not a major factor influencing craniomaxillofacial hard tissue development in patients with UCLP; moreover, PNAM treatment showed significant correction of skeletal deviation at the base of the nose.
    CONCLUSIONS: Follow-up in early childhood has shown that PNAM treatment administered during the neonatal stage does not impede maxillary development and has benefits in correcting nasal floor deviation. It is a viable option for improving nasal deformity in children with unilateral cleft lip and palate.
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  • 文章类型: Journal Article
    背景:本研究旨在根据颞下颌关节紊乱病的风险确定不同体积的髁骨形态和相应的牙骨特征之间的差异。
    方法:60例II类超发散性成年女性颅面螺旋计算机断层扫描数据分为正常,再吸收,扁平,和基于髁突骨性形式的骨赘组。比较各组髁突体积,并从三个维度评估了它们与牙齿骨骼特征的相关性。使用配对最小显著性差异检验来检查组间的个体配对差异,单向方差分析用于测量多组间的差异。Pearson相关性和Spearman秩相关分析用于确定髁突体积与牙面特征之间的相关性。在p<0.05时确立统计学显著性。
    结果:正常组髁突体积明显大于改变组,亚组之间没有显着差异。con突体积的减少与下颌骨的收缩和顺时针旋转,下颌骨较短有关。髁突体积与超喷量呈负相关,下前牙和后牙的牙槽高度,下牙的矢状倾斜,下颌第一磨牙磨牙间宽度,和相应牙槽峰之间的宽度。
    结论:II类女性成人的多个三维牙骨特征与髁突骨性改变有关,无论形式如何。这些结果可能有助于指示颞下颌关节的潜在病理变化,并为这些患者制定适当的治疗计划。
    This study aimed to determine the differences among various volumes of condylar osseous patterns and the corresponding dentoskeletal characteristics based on the risk of temporomandibular disorder.
    Craniofacial spiral computed tomography data of 60 Class II hyperdivergent female adults were divided into normal, resorptive, flattened, and osteophyte groups based on condylar osseous forms. The condylar volumes of each group were compared, and their correlations with the dentoskeletal characteristics were assessed in three dimensions. Pairwise least significant difference tests were used to examine individual pairwise differences between groups, and one-way analysis of variance was used to measure differences among multiple groups. Pearson correlation and Spearman rank correlation analyses were used to determine the correlation between condylar volume and dentofacial characteristics. Statistical significance was established at p < 0.05.
    The condylar volume in the normal group was significantly greater than that in the changed groups, with no significant differences between the subgroups. The decrease in condylar volume was associated with a retruded and clockwise-rotated mandible with shorter rami. Condylar volume was negatively correlated with overjet, the alveolar height of the lower anterior and posterior teeth, sagittal inclinations of the lower teeth, intermolar width of the mandibular first molars, and width between the corresponding alveolar crests.
    Multiple three-dimensional dentoskeletal characteristics of Class II hyperdivergent female adults are correlated with condylar bony changes, regardless of the form. These results could be helpful in indicating potential pathological changes in the temporomandibular joint and in making proper treatment plans for these patients.
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  • 文章类型: Journal Article
    目的:本研究旨在使用锥形束计算机断层扫描(CBCT)评估保留髁头的下颌骨重建后髁突的位置变化。此外,评估与术前状态相比的关节间隙变化和整体体积空间。
    方法:这项前瞻性研究包括30例患者(60个关节)进行单侧下颌骨切除和重建,并保留髁头。Helkimo指数和术前(T1),术后2周(T2),收集并处理至少六个月后的随访CBCT(T3),以使用AnatomageInvivo6评估髁突位置和TMJ关节间隙。使用学生t检验和重复测量的ANOVA统计学。小于0.05的P值被认为具有统计学意义。
    结果:30例患者(14例男性,包括16名女性),平均年龄为40.01±12.7岁(范围为18.1-62.9岁)。在肿瘤方面,三个时间点(T1,T2,T3)之间的髁突垂直位置和中外侧位置存在显著差异.手术后立即,在T2时,髁突明显向下移位,在最后一个随访期(T3)后变大(p=0.007)。前后方向的髁突位置相对稳定,三个时间点之间没有显着差异(p=0.915)。在非肿瘤方面,髁突位置在中外侧和前后位置相对稳定。在肿瘤方面,下颌骨重建后,所有TMJ空间的大小均显着增加(T2和T3)。然而,在非肿瘤方面,前部,后部,术后内侧关节间隙明显改变。
    结论:保留髁突的下颌骨重建后,与非肿瘤侧相对稳定的髁相比,髁突位置和体积测量立即发生明显变化,并且随着时间的推移持续为永久性变化。根据赫尔基摩指数,患者变得适应术后的变化,双方之间没有显着差异。
    OBJECTIVE: This study aimed to evaluate the condylar positional changes following mandibular reconstruction with preservation of the condylar head using Cone-Beam Computed Tomography (CBCT). Also, to assess joint space changes and the overall volumetric space compared to the preoperative status.
    METHODS: This prospective study included 30 patients (60 joints) subjected to unilateral mandibular resection and reconstruction with preservation of the condylar head. The Helkimo index and preoperative (T1), two weeks postoperative (T2), and follow-up CBCTs (T3) after at least six months were gathered and processed to evaluate the condylar position and TMJ joint space using Anatomage Invivo 6. A student\'s t-test and repeated-measures ANOVA statistics were used. A P value of less than 0.05 was considered statistically significant.
    RESULTS: Thirty patients (14 males, 16 females) with a mean age of 40.01 ± 12.7 years (a range of 18.1-62.9 years) were included. On the tumor side, there were significant variances in the vertical and mediolateral condylar positions between the three-time points (T1, T2, T3). Immediately after the operation, the condyles were significantly displaced in a downward direction at T2, which became larger after the last follow-up period (T3) (p = 0.007). The condylar positions at the anteroposterior direction were relatively stable without significant differences between the three times points (p = 0.915). On the non-tumor side, the condylar positions were relatively stable in the mediolateral and anteroposterior positions. In the tumor side, all of the TMJ spaces were significantly increased in size following the mandibular reconstructions (T2 and T3). However, on the non-tumor side, the anterior, posterior, and medial joint spaces were significantly changed postoperatively.
    CONCLUSIONS: After mandibular reconstruction with condylar preservation, the condylar position and volumetric measurement immediately changed noticeably and continued to be a permanent change over time compared to relatively stable condyles on the non-tumor side. According to Helkimo index, patients become adapted to the postoperative changes without significant differences between the two sides.
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  • 文章类型: Journal Article
    背景:这项研究通过三维测量调查了中国北方人群的肱骨几何和形态参数的特征,并比较了不同地理区域人群的肱骨形态是否存在差异。
    方法:获得了80例肱骨的计算机断层扫描,重建和测量。比较了性别和两侧之间肱骨形态参数的差异。使用相关性分析来探索参数之间可能的相关性。根据当前和先前研究的汇总结果,比较了西亚和东亚人群之间肱骨几何形态参数的差异。
    结果:肱骨头半径曲率的平均值(和标准偏差),弧角,直径,厚度为151.79±6.69°,23.36±2.08mm,肱骨头冠状面为44.83±3.92mm,17.55±1.84mm,和152.05±8.82°,21.81±1.88mm,肱骨头横向平面41.77±3.44mm和16.52±1.92mm。肱骨头内侧偏移和后偏移的平均值为7.34±2.47mm和0.08±1.72mm。肱骨头倾角,肱骨颈轴的弧角和曲率半径平均为137.69±4.92°,34.7±5.29°,55.76±13.43mm。Superior,劣等,前,肱骨解剖颈后凹角平均为150.41±10.91°,146.55±10.12°,146.43±13.53°和149.33±14.07°。大结节的平均高度,小结节的高度,深度,结节间沟的凹角和体积为14.19±1.7mm,8.9±1.54mm,0.92±0.31mm3,31.28±9.61mm,4.98±1.19mm,89.35±17.62°。大结节的上角度平均为161.04±7.84°,大结节的上角度为165.94±3.6°。发现性别和两侧肱骨近端参数存在差异。肱骨近端参数与年龄无相关性。肱骨形态学参数之间存在相关性。东亚人群的肱骨近端形态与西方人群不同。
    结论:本研究将为肩关节疾病的诊断和分类提供参考。设计假体和器械,提高手术精度和指导患者康复。
    BACKGROUND: This study investigated the characteristics of humeral geometric and morphological parameters in northern Chinese population by three-dimensional measurements, and compared whether there were differences in humeral morphology among populations from different geographical regions.
    METHODS: Computed tomography scans of 80 humerus were obtained, reconstructed and measured. Differences in humeral morphological parameters between genders and sides were compared. Correlation analysis was used to explore possible correlations among the parameters. The differences in humeral geometric morphometric parameters between Western and East Asian populations were compared according to pool results of present and previous studies.
    RESULTS: The average (and standard deviation) of humeral head radius curvature, arc angle, diameter, and thickness was 151.79 ± 6.69°, 23.36 ± 2.08 mm, 44.83 ± 3.92 mm and 17.55 ± 1.84 mm in coronal humeral head plane, and 152.05 ± 8.82°, 21.81 ± 1.88 mm, 41.77 ± 3.44 mm and 16.52 ± 1.92 mm in transversal humeral head plane. The average of the humeral head medial offset and posterior offset was 7.34 ± 2.47 mm and 0.08 ± 1.72 mm. Humeral head inclination angle, arc angle and radius curvature of humeral neck-shaft averaged 137.69 ± 4.92°, 34.7 ± 5.29° and 55.76 ± 13.43 mm. Superior, inferior, anterior, posterior concave angle of humeral anatomical neck averaged 150.41 ± 10.91°, 146.55 ± 10.12°, 146.43 ± 13.53° and 149.33 ± 14.07°. The average of height of the greater tuberosity, height of the lesser tuberosity, depth, concave angle and volume of the intertubercular groove was 14.19 ± 1.7 mm, 8.9 ± 1.54 mm, 0.92 ± 0.31 mm3, 31.28 ± 9.61 mm, 4.98 ± 1.19 mm and 89.35 ± 17.62°. The upper angle of the greater tuberosity averaged 161.04 ± 7.84°, the upper angle of the greater tuberosity was 165.94 ± 3.6°. Differences in parameters of proximal humerus between genders and sides were found. There was no correlation between parameters of proximal humerus and age. Correlations were found among humeral morphological parameters. East Asian populations differed in proximal humeral morphology from Western populations.
    CONCLUSIONS: This study will provide references for diagnosing and classifying shoulder disease, designing prosthesis and instrument, enhancing surgical precision and guiding patient recovery.
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  • 文章类型: Journal Article
    背景:下颌中外侧位置的三维(3D)详细评估,下颌髁突位置,在现有文献中尚未报道颞下颌关节疾病(TMD)和下颌偏斜(MD)患者的稳定夹板(SS)治疗后的颞下颌关节(TMJ)空间。因此,这项研究的目的是三维分析的骨骼和骨颞下颌关节的变化,在稳定夹板治疗后的成年患者颞下颌关节疾病和下颌偏曲。
    方法:本研究是一项回顾性临床研究,纳入26名成人TMD和MD患者,平均年龄24.86岁。使用颞下颌关节紊乱病诊断标准(DC/TMD)来诊断TMD。每周调整SS,直至发生咬合接触稳定,然后按月调整,患者被指示在夜间佩戴至少10小时。消除TMD症状后去除SS(TMJ/触诊时肌肉疼痛,肌肉痉挛,并发出咔嗒声),并使两个髁完全坐在肌肉骨骼稳定的位置。分析了治疗前后的锥形束计算机断层扫描(CBCT)。下颌中外侧位置,TMJ空间,使用Mimics21.0软件对下颌髁突位置进行三维分析。进行配对t检验或Wilcoxon秩和检验,显著性水平为P<0.05。
    结果:SS治疗的治疗期为10.07±3.1个月。偏离下巴改善了69.23%的样本;改善范围>0mm≤3.9mm。下颌旋转从3.58±2.02°明显降低至3.17±1.60。斜侧关节颞下颌关节上、后间隙由2.49±0.88mm和1.25±0.79mm明显增加为2.98±1.02mm和1.86±0.72mm,分别。双侧髁头位置与X轴和Z轴的差值从2.50±1.56mm和2.30±1.57mm明显下降到1.64±1.58mm和1.82±1.11mm,分别。
    结论:稳定夹板治疗TMD患者的主要位置效应包括相当大的下颌偏斜矫正,改善面部不对称,并将髁移入稳定的髁位置;这些是通过促进下颌骨绕Z(滚动)和Y(偏航)轴旋转以及向前旋转来完成的,向下,和向外的髁运动在偏离的一侧,分别。
    Three-dimensional (3D) detailed evaluations of the mandibular mediolateral position, mandibular condylar position, and temporomandibular joint (TMJ) spaces following stabilization splints (SS) therapy in patients with temporomandibular joint disorders (TMD) and mandibular deviation (MD) have not been reported in the available literature. Accordingly, this study aimed to three-dimensionally analyze the skeletal and bony temporomandibular joint changes following stabilization splint therapy in adult patients with temporomandibular joint disorders and mandibular deviation.
    This study is a retrospective clinical study that enrolled 26 adult patients with TMD and MD with a mean age of 24.86 years. The Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) was used to diagnose TMD. SS was adjusted weekly until occlusal contact stabilization occurred, and then adjusted monthly, patients were instructed to wear it at night for at least 10 h. The SS was removed after the elimination of TMD symptoms (TMJ/muscle pain on palpation, muscle spasm, and clicking) and having both condyles completely seated in a musculoskeletally stable position. Pre- and post-therapeutic Cone Beam Computed Tomography (CBCT) was analyzed. Mandibular mediolateral position, TMJ spaces, and mandibular condyle position were analyzed three-dimensionally using Mimics 21.0 software. Paired t-test or Wilcoxon rank-sum test was performed, and the significance level was considered at P < 0.05.
    The treatment period with SS therapy was 10.07 ± 3.1 months. The deviated chin was improved in 69.23% of the sample; the range of improvement was > 0 mm ≤ 3.9 mm. The mandibular rotation was significantly decreased from 3.58 ± 2.02° to 3.17 ± 1.60. The deviated side\'s superior and posterior joint TMJ spaces were significantly increased from 2.49 ± 0.88 mm and 1.25 ± 0.79 mm to 2.98 ± 1.02 mm and 1.86 ± 0.72 mm, respectively. The value of the difference from the bilateral condyle head position to the X and Z axes significantly decreased from 2.50 ± 1.56 mm and 2.30 ± 1.57 mm to 1.64 ± 1.58 mm and 1.82 ± 1.11 mm, respectively.
    The main positional effect of the stabilization splint treatment in TMD patients with MD includes considerable correction of mandibular deviation, improving facial asymmetry, and moving the condyle into a stable condylar position; these were done by promoting the mandible to rotate around the Z (roll) and Y (yaw) axes and by forward, downward, and outward condylar movement on the deviated side, respectively.
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  • 文章类型: Journal Article
    聚糖是自然界中最丰富的有机聚合物。它们对活生物体至关重要,并调节广泛的生物学功能。然而,基于质谱的聚糖异构体的鉴定仍然具有挑战性,由于其结构的复杂性,包括其复杂的组成,联系,和异头构型。在这项研究中,两个新的复杂离子,单核铜结合的二聚体离子[(Cu2)(A)(L-His)-H]和单核铜结合的季铵离子[(Cu2)(A)(L-Ser)3-H](其中A表示二糖,和L-Ser/His表示1-丝氨酸/组氨酸),设计用于14种二糖异构体的基于碰撞诱导解离的鉴定和相对定量。当将上述两种复杂离子的独特碎片模式映射到三维矢量中时,所有的异构体都是完全区分的。值得注意的是,所建立的方法只能使用基于组氨酸络合物离子的键特异性片段离子的串联质谱法来鉴定键异构体的混合物。最后,该方法已成功应用于乳饮料中两种二糖异构体(乳糖和蔗糖)的鉴定和相对定量。总之,该方法对二糖异构体的细微结构差异敏感,有可能用于各种聚糖的分化。
    Glycans are the most abundant organic polymers in nature. They are essential to living organisms and regulate a wide range of biological functions. However, mass spectrometry-based identification of glycan isomers remains challenging due to the complexity of their structures including their complex compositions, linkages, and anomeric configurations. In this study, two novel complex ions, the mononuclear copper-bound dimeric ions [(Cu2+)(A)(L-His)-H]+ and the mononuclear copper-bound quaternary ions [(Cu2+)(A)(L-Ser)3-H]+ (where A denotes a disaccharide, and L-Ser/His denotes l-serine/histidine), were designed for the collision-induced dissociation-based identification and relative quantification of 14 disaccharide isomers. When the unique fragmentation patterns of the above two types of complex ions were mapped into a three-dimensional vector, all the isomers were completely distinguished. Of note, the established method is able to identify mixtures of linkage isomers only using tandem mass spectrometry based on linkage-specific fragment ions of histidine-based complex ions. Finally, the method was successfully applied to the identification and relative quantification of two disaccharide isomers (lactose and sucrose) in dairy beverages. In conclusion, the established method is sensitive to subtle structural differences in disaccharide isomers and has the potential to be used for the differentiation of various glycans.
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  • 文章类型: Journal Article
    To find out which structure is crucial for the formation of shoulder impingement syndrome with the purpose of directing surgical procedures of subacromial decompression and discussing whether it is necessary to manage acromioclavicular joint during operation and how to do it properly.
    METHODS: This was a retrospective study. Clinical data and preoperative computed tomography (CT) images were collected from patients who were diagnosed with rotator cuff tears between January 2017 and August 2019 (sample size: 46) and those who were diagnosed without rotator cuff tears between March 2018 and August 2019 (sample size: 44) in our institution, respectively. Three-dimensional models of shoulders were established by multiplanar reconstruction of CT scans and measurements were performed on these models. The parameters such as the acromial length and width, the axial tilt, and the distance from acromial margin to glenoid plane were measured in an adjusted axial plane, and the critical shoulder angle and the spatial volume under acromioclavicular joint were measured in an adjusted coronal plane. The demographic characteristics, the acromial morphology and the spatial volume under acromioclavicular joint were compared to find significant differences between the two groups. The association between the axial tilt and the distance from acromial margin to glenoid plane was evaluated by an ordinary least squares linear regression.
    RESULTS: The patients with rotator cuff tears consisted of 16 males and 30 females, among which 30 right shoulders and 16 left shoulders were included. The patients without rotator cuff tears consisted of 28 males and 16 females, among which 15 right shoulders and 29 left shoulders were involved. Significant differences between the groups were found in the acromial width (3.332 cm vs 3.111 cm), the axial tilt (33.765° vs 23.829°), the critical shoulder angle (32.630° vs 30.363°), the distance from anterior 3 cm of lateral acromial margin (range, 2.476 cm-3.302 cm vs 1.993 cm-3.089 cm), and anterior 0.9 cm of medial acromial margin (range, 0.967 cm-2.369 cm vs 0.668 cm-1.993 cm) to glenoid plane, and the spatial volume under acromioclavicular joint (1.089 cm vs 1.446 cm) in the two groups. No significant differences were found in the age (60.0 years vs 58.3 years) or the acromial length (4.187 cm vs 4.184 cm). Significant association was revealed by linear regression analysis between the axial tilt and the distance from anterior two-thirds of lateral acromial margin to glenoid plane, and similar association was also found in the anterior half of medial margin.
    CONCLUSIONS: Anterior two-thirds of lateral acromial margin, anterior half of medial acromial margin, and inferior aspect of acromioclavicular joint are crucial structures and need to be fully decompressed when treating patients with rotator cuff tears.
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  • 文章类型: Journal Article
    Cake layer formation is the dominant ultrafiltration membrane fouling mechanism after long-term operation. However, precisely analyzing the cake-layer structure still remains a challenge due to its thinness (micro/nano scale). Herein, based on the excellent depth-resolution and foulant-discrimination of time-of-flight secondary ion mass spectrometry, a three-dimensional analysis of the cake-layer structure caused by natural organic matter was achieved at lower nanoscale for the first time. When humic substances or polysaccharides coexisted with proteins separately, a homogeneous cake layer was formed due to their interactions. Consequently, membrane fouling resistances induced by proteins were reduced by humic substances or polysaccharides, leading to a high flux. However, when humic substances and polysaccharides coexisted, a sandwich-like cake layer was formed owing to the asynchronous deposition based on molecular dynamics simulations. As a result, membrane fouling resistances were superimposed, and the flux was low. Furthermore, it is interesting that cake-layer structures were relatively stable under common UF operating conditions (i.e., concentration and stirring). These findings better elucidate membrane fouling mechanisms of different natural-organic-matter mixtures. Moreover, it is demonstrated that membrane fouling seems lower with a more homogeneous cake layer, and humic substances or polysaccharides play a critical role. Therefore, regulating the cake-layer structure by feed pretreatment scientifically based on proven mechanisms should be an efficient membrane-fouling-control strategy.
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