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81.
C. Roth W. Parson C. Strobl R. Lagacé M. Short 《The Australian journal of forensic sciences》2019,51(4):S52-S55
ABSTRACTMitochondrial DNA (mtDNA) sequencing is a valuable forensics tool in determining the source of DNA obtained from degraded, damaged or small biological samples. However, despite the recent advances in Massively Parallel Sequencing (MPS), the analysis of mtDNA has remained challenging: alignments can be misleading and may result in incorrect variant calls, and contamination from nuclear DNA from small samples may obscure true variants. In this article, we discuss an integrated approach to solving these issues in a new mito variant caller that integrates various sources of knowledge about mtDNA, including phylotree, EMPOP and NUMTs statistics, and that avoids many of the pitfalls of standard algorithms. The knowledge is integrated into the alignment algorithm itself to distinguish true variant calls from NUMT contamination and sequencing artefacts. 相似文献
82.
83.
目的 :分析退行性脊柱侧凸(adult degenerative scoliosis,ADS)患者椎旁肌(多裂肌、竖脊肌)MRI影像退变程度与脊柱-骨盆参数之间的关系,为ADS患者矢状位失平衡评估提供新的线索。方法:回顾性分析在我院就诊的女性ADS患者52例,年龄55～65岁,收集患者人口统计学资料,分别测量患者腰椎MRI上L1～S1椎间盘层面椎旁肌(多裂肌、竖脊肌)横截面积(cross-sectional area,CSA)、脂肪化比例(fat saturation fraction,FSF),并在患者脊柱全长X线片上测量冠状位和矢状位的影像学参数,包括冠状位Cobb角、矢状位垂直偏距(sagittal vertical axis,SVA)、胸椎后凸角(thoracic kyphosis,TK)、腰椎前凸角(lumbar lordosis,LL)、骨盆倾斜角(pelvic tilt,PT)、骨盆入射角(pelvic incidence,PI)、骶骨倾斜角(sacral slope,SS)、PI-LL,对椎旁肌L1～S1各层面FSF行单因素方差分析并进行LSD事后多重比较,利用Pearson相关分析比较椎旁肌退变程度和脊柱-骨盆参数之间的关系。结果:L1～S1各层面FSF有显著性差异(P0.01),L5/S1层面椎旁肌FSF明显大于其他层面(P0.05)。冠状位Cobb角与L1/2、L2/3、L3/4、L4/5椎间盘层面CSA呈负相关(r=-0.358、-0.367、-0.329、-0.283,P0.05)。椎旁肌FSF与PT在L1～S1各层面呈正相关(r=0.487、0.394、0.354、0.356、0.355,P0.05),而与SS呈负相关(r=-0.494、-0.440、-0.373、-0.301、-0.300,P0.05)。椎旁肌FSF与LL在L1/2、L2/3层面呈负相关(r=-0.398、-0.328,P0.05)。椎旁肌总体FSF(TFSF)与PT呈正相关(r=0.395,P0.01),与LL呈负相关(r=-0.345,P0.05)。L1～S1各层面椎旁肌CSA、FSF与SVA、PI、TK的Pearson相关分析结果无统计学意义(P0.05)。BMI与L1～S1各层面椎旁肌CSA呈正相关(P0.05),而与椎旁肌各层面FSF的Pearson相关分析结果无统计学意义(P0.05)。结论:在ADS患者中,椎旁肌FSF与PT有明显的正相关性,提示椎旁肌的退变可能参与了脊柱退变和代偿机制的过程,椎旁肌FSF可能反映了ADS患者矢状位失平衡的严重程度。 相似文献
84.
【摘要】 目的：评价椎体矢状切除技术在胸腰椎肿瘤中的安全性、有效性,探讨椎体分区、分型对手术的指导意义。方法：以椎体椎弓根的内侧缘、外侧缘和椎体中线为界,将椎体的解剖部位对称地分为Ⅰ/Ⅱ/Ⅲ区,并根据此分区进行分型,Ⅰ型,肿瘤累及Ⅰ区,矢状切除范围为同侧Ⅰ～Ⅱ区;Ⅱ型,肿瘤累及Ⅱ区,矢状切除同侧Ⅰ～Ⅲ区;Ⅲ型,肿瘤累及Ⅲ区,矢状切除同侧Ⅰ～Ⅲ区及对侧Ⅲ区。根据纳入排除标准,收集于2018年6月～2021年12月在我科进行胸腰椎肿瘤矢状切除的患者共8例,男性6例（75%）,女性2例（25%）,平均年龄37.8±4.8岁。骨肉瘤2例,软组织肉瘤2例,转移癌2例,良性局部侵袭性肿瘤2例。Ⅰ型1例,Ⅱ型2例,Ⅲ型5例。分别收集患者一般资料、手术相关临床数据,包括肿瘤累及分区、手术时间、术中失血量、重建方式、手术并发症、复发率、远期并发症、Frankel分级,随访观察该术式的治疗效果。结果：随访时间22.3±3.9个月（12～40个月）,术中失血量为1812.5±333.0ml,手术时间为369.6±27.7min。有1例软组织切缘阳性,因患者在外院首次手术造成硬膜粘连,我院进行第二次手术;所有患者骨切缘均为阴性。肿瘤学结果包括1例肿瘤局部复发合并远处转移,局部复发率12.5%（1/8）,1例远处转移,无感染及死亡病例,未见内固定失败病例。Frankel分级手术后未见恶化情况。结论：基于我们提出的分区、分型系统,可以有效指导胸腰椎肿瘤的椎体矢状切除,保留部分椎体,有助于减少手术并发症。 相似文献
85.
在30具成年男尸躯体连续矢状断面标本上，观测了左，右侧胸膜顶与锁骨的关系，结果如下：左侧胸膜顶最贞点高出锁骨上面平均为1．20cm，右侧平均为1．70cm，左侧胸膜顶最凸点距正中矢状面平均为3．20cm，右侧平均为3．66cm，经回归分析发现胸廓指数与左侧胸膜顶的高度存在着回归关系，右侧则无这一关系。 相似文献
86.
Sequence Determination and Molecular Analysis of Two Strains of Bovine Parainfluenza Virus Type 3 that are Attenuated for Primates 总被引：1，自引：0，他引：1
The Kansas/15626/84 (Ka) and Shipping Fever (SF) strains of bovine parainfluenza virus type 3 (BPIV3) replicate less efficiently than human PIV3 (HPIV3) in the upper and lower respiratory tract of rhesus monkeys, and BPIV3 Ka is also highly attenuated in humans and is in clinical trials as a candidate vaccine against HPIV3. To initiate an investigation of the genetic basis of the observed attenuation phenotype of BPIV3 in primates, the complete genomic sequences of Ka and SF genomes were determined and compared to those of BPIV3 strain 910N and two HPIV3 strains, JS and Wash/47885/57. There is a high degree of identity between the five PIV3 viruses in their 55 nucleotide (nt) leader (83.6%) and 44 nt trailer (93.2%) sequences. The five viruses display amino acid sequence identity ranging from 58.6% for the phosphoprotein to 89.7% for the matrix protein. Interestingly, the majority of amino acid residues found to be variable at a given position in a five-way protein alignment are nonetheless identical within the viruses of either host species (BPIV3 or HPIV3). These host-specific residues might be products of distinct selective pressures on BPIV3 and HPIV3 during evolution in their respective hosts. These host-specific sequences likely include ones which are responsible for the host range differences, such as the efficient growth of BPIV3 in bovines compared to its restricted growth in primates. It should now be possible using the techniques of reverse genetics to import sequences from BPIV3 into HPIV3 and identify those nt or protein sequences which attenuate HPIV3 for primates. This information should be useful in understanding virus-host interactions and in the development of vaccines to protect against HPIV3-induced disease. 相似文献
87.
George M. Ghobrial Nathan H. Lebwohl Barth A. Green Joseph P. Gjolaj 《The spine journal》2017,17(11):1594-1600
Background Context
Prior reports have compared posterior column osteotomies with pedicle subtraction osteotomies in terms of utility for correcting fixed sagittal imbalance in adolescent patients with deformity. No prior reports have described the use of multilevel Smith-Petersen Osteotomies (SPOs) alone for surgical correction in the adult spinal deformity (ASD) population.Purpose
The study aimed to determine the utility of multilevel SPOs in the management of global sagittal imbalance in ASD patients.Study Design/Setting
This is a retrospective observational study at a single academic center.Patient Sample
The sample included 85 ASD patients.Outcome Measures
This is a radiographic outcomes cohort study.Methods
The radiographs of 85 ASD patients were retrospectively evaluated before and after long-segment (>5 spinal levels) fusion and multilevel SPO (≥3 levels) for sagittal imbalance correction. The number of osteotomies, correction in regional lumbar lordosis (LL), and correction per osteotomy was evaluated. Independent predictors of correction per SPO were evaluated with a hierarchical linear regression analysis.Results
Eighty-five patients (mean age: 67.5±11 years) were identified with ASD (372 SPOs). The mean preoperative sagittal vertical axis (SVA) and T1 pelvic angle (TPA) were 8.16±6.75?cm and 25°±13.23°, respectively. The mean postoperative central sacral vertical line (CSVL) and SVA were 0.67±0.70?cm and 1.29±5.41?cm, respectively. The mean improvement in SVA was 6.29?cm achieved with a correction of approximately 5.05° per SPO. The mean LL restoration was 20.3°±13.9°, and 33(39%) patients achieved a final pelvic incidence minus lumbar lordosis (PI-LL) ≤10°. Fifty-four (64%) achieved a postoperative PI-LL ≤15°, 75 (88%) with a PI-LL ≤20°, and 85 (100%) achieved a PI-LL ≤25°. Correction per SPO was similar regardless of prior fusion (4.87° vs. 5.72° for revisions, p=.192). In a subgroup analysis of SVA greater than 10?cm, there was no significant difference in the final LL, thoracic kyphosis, PI-LL, SVA, CSVL, and TPA, as compared with SVA <10?cm. The LL was the only independent predictor of osteotomy correction per level (LL: β coefficient=?0.108, confidence interval: ?0.141 to 0.071, p<.0001).Conclusions
Multilevel SPOs are feasible for restoration of LL as well as sagittal and coronal alignment in the ASD population with or without prior instrumented fusion. 相似文献88.
Aaron J. Buckland Subaraman Ramchandran Louis Day Shay Bess Themistocles Protopsaltis Peter G. Passias Bassel G. Diebo Renaud Lafage Virginie Lafage Akhila Sure Thomas J. Errico 《The spine journal》2017,17(11):1601-1610
Background Context
Patients with degenerative lumbar stenosis (DLS) adopt a forward flexed posture in an attempt to decompress neural elements. The relationship between sagittal alignment and severity of lumbar stenosis has not previously been studied.Purpose
We hypothesized that patients with increasing radiological severity of lumbar stenosis will exhibit worsening sagittal alignment.Study Design
This is a cross-sectional study.Patient Sample
Our sample consists of patients who have DLS.Outcome Measures
Standing pelvic, regional, lower extremity and global sagittal alignment, and health-related quality of life (HRQoL) were the outcome measures.Methods
Patients with DLS were identified from a retrospective clinical database with corresponding full-body stereoradiographs. Exclusion criteria included coronal malalignment, prior spine surgery, spondylolisthesis>Grade 1, non-degenerative spinal pathology, or skeletal immaturity. Central stenosis severity was graded on axial T2-weighted magnetic resonance imaging (MRI) from L1–S1. Foraminal stenosis and supine lordosis was graded on sagittal T1-weighted images. Standing pelvic, regional, lower extremity, and global sagittal alignment were measured using validated software. The HRQoL measures were also analyzed in relation to severity of stenosis.Results
A total of 125 patients were identified with DLS on appropriate imaging. As central stenosis grade increased, patients displayed significantly increasing standing T1 pelvic angle, pelvic tilt, sagittal vertical axis, and pelvic incidence-lumbar lordosis (p<.05). No significant difference wasfound in pelvic incidence, supine lordosis, thoracic kyphosis, or T1 spinopelvic inclination between central stenosis groups. Despite similar supine lordosis between stenosis groups, patients with Grades 2 and 3 stenosis had less standing lordosis, suggesting antalgic posturing. Upper lumbar (L1–L3) stenosis predicted worse alignment than lower lumbar (L4–S1) stenosis.Increasing severity of foraminal stenosis was associated with reduced lumbar lordosis; however, no significant postural difference in lordosis, thoracolumbar, or lower extremity compensatory mechanisms were noted between foraminal stenosis groups. Stenosis grading did not predict worsening HRQoLs in central or foraminal stenosis.Conclusions
Severity of central lumbar stenosis as graded on MRI correlates with severity of sagittal malalignment. These findings support theories of sagittal malalignment as a compensatory mechanism for central lumbar stenosis. 相似文献89.
Fábio A. Araújo Ana Martins Nuno Alegrete Laura D. Howe Raquel Lucas 《The spine journal》2017,17(10):1426-1434
Background Context
In each specific habitual standing posture, gravitational forces determine the mechanical setting provided to skeletal structures. Bone quality and resistance to physical stress is highly determined by habitual mechanical stimulation. However, the relationship between bone properties and sagittal posture has never been studied in children.Purpose
This study aimed to investigate the association between bone physical properties and sagittal standing postural patterns in 7-year-old children. We also analyzed the relationship between fat or fat-free mass and postural patterns.Study Design
Cross-sectional evaluation.Patient Sample
This study was performed in a sample of 1,138 girls and 1,260 boys at 7 years of age participating in the Generation XXI study, a population-based cohort of children followed since birth (2005–2006) and recruited in Porto, Portugal.Outcome Measures
Sagittal standing posture was measured through photographs of the sagittal right view of children in the standing position. Three angles were considered to quantify the magnitude of major curves of the spine and an overall balance measure (trunk, lumbar, and sway angles). Postural patterns were identified using latent profile analysis in Mplus.Methods
Weight and height were measured. Total body less head fat or fat-free mass and bone properties were estimated from whole-body dual-energy X-ray absorptiometry scans. The associations of fat or fat-free mass and bone physical properties with postural patterns were jointly estimated in latent profile analysis using multinomial logistic regressions.Results
The identified patterns were labeled as Sway, Flat, and “Neutral to Hyperlordotic” (in girls), and “Sway to Neutral,” Flat, and Hyperlordotic (in boys). In both genders, children in the Flat pattern showed the lowest body mass index, and children with a rounded posture presented the highest: mean differences varying from ?0.86?kg/m2 to 0.60?kg/m2 in girls and from ?0.70?kg/m2 to 0.62?kg/m2 in boys (vs. Sway or “Sway to Neutral”). Fat and fat-free mass were inversely associated with a Flat pattern and positively associated with a rounded posture: odds ratio (OR) of 0.23 per standard deviation (SD) fat and 0.70 per SD fat-free mass for the Flat pattern, and 1.85 (fat) and 1.43 (fat-free) for the Hyperlordotic pattern in boys, with similar findings in girls. The same direction of relationships was observed between bone physical properties and postural patterns. A positive association between bone (especially bone mineral density) and a rounded posture was robust to adjustment for age, height, and body composition (girls: OR=1.79, p=.006 fat-adjusted, OR=2.00, p=.014 fat-free mass adjusted; boys: OR=2.02, p=.002 fat-adjusted, OR=2.42, p<.001 fat-free mass adjusted).Conclusions
In this population-based pediatric setting, there was an inverse association between bone physical properties and a Flat posture. Bone and posture were more strongly positively linked in a rounded posture. Our results support that both bone properties and posture mature in a shared and interrelated mechanical environment, probably modulated by pattern-specific anthropometrics and body composition. 相似文献90.
Mitsuru Yagi Hideaki Ohne Tsunehiko Konomi Kanehiro Fujiyoshi Shinjiro Kaneko Masakazu Takemitsu Masafumi Machida Yoshiyuki Yato Takashi Asazuma 《The spine journal》2017,17(3):409-417