自体与异体移植重建膝关节前交叉韧带的关键技术

目的:探索膝关节前交叉韧带重建术的各个关键技术环节,为提高前交叉韧带修复的临床效果提供理论和实践依据。方法:通过分析与总结与前交叉韧带重建相关的文献资料,包括其手术方式、移植物的选择、骨道定位、髁间窝成形、移植物预张与张力、移植物固定等,同时结合作者的工作经验旨在进一步提高前交叉韧带重建技术。结果:①手术方式选择:膝关节镜下生物材料移植重建前交叉韧带取得比以往优良的临床效果,已得到广泛认可。多数采用单束重建,部分学者正在尝试双束重建以改善移植物生物力学性能。②移植材料的选择:包括自体和同种异体材料,其中自体骨-髌腱-骨与腘绳肌腱最为常用。骨-髌腱-骨由于两端带有骨块,固定牢靠,允许早期重返运动场,颇受年轻运动员青睐。腘绳肌腱取材切口小,术后很少出现膝前痛,但其稳定性不如骨-髌腱-骨,且术后相对容易出现骨隧道扩大。异体移植物在体内结合、重塑速度较自体移植慢,但若经过严格的供体筛选、合理的组织取材、消毒和保存,而不减弱移植物强度,仍可取得与自体移植相当的效果。③骨道位置:正确的骨道定位非常重要,骨道位置太靠前会造成髁间窝撞击和伸直受限。研究表明,术中采用骨性标志定位法要比采用软组织标志定位法准确,术中摄片有助于骨道位置的正确定位。④髁间窝成形术:髁间窝成形的目的是为了便于更清楚的观察髁间窝后侧,同时也是为了避免髁间窝撞击综合征的发生,由于髁间窝过度成形会增加关节出血、疼痛、肿胀以及骨赘生长,所以一般不主张广泛的髁间窝成形,除非术中确有必要时才进行。⑤移植物预张与张力:移植物初始张力不够会导致膝关节持续松弛,而张力过高会限制关节活动并加速关节退变。目前对于最佳的初始张力尚无确切说法。⑥固定:现在已经研制出许多不同类型的固定材料。对于骨-髌腱-骨而言,界面挤压螺钉单切口重建前交叉韧带时,股骨侧靠近关节腔侧固定,胫骨侧远离关节腔侧固定,双切口技术时胫骨侧靠近关节腔侧固定,股骨侧远离关节腔侧固定。股骨侧固定完毕后,膝关节取何角度对胫骨侧进行固定尚存争议。膝关节稍屈曲状态下固定不容易发生松弛,但正常的膝关节在前后方向上是允许有一定松弛度的。有些学者认为在膝关节完全伸直状态下固定可以避免屈曲挛缩畸形的发生并允许前后方向有轻度松弛。而有些学者认为在膝关节稍微屈曲状态下固定会更紧。结论:要真正做到解剖、生物力学、生理功能全方位重建,前交叉韧带重建技术,仍需不断完善,分子生物学、基因工程和组织工程技术的发展以及计算机辅助机器人手术的开展会使前交叉韧带重建技术日臻完善。     

Spatial and temporal distribution of Ki-67 proliferation marker, Bcl-2 and Bax proteins in the developing human tooth

Objective

To investigate the spatial and temporal expression of proliferation Ki-67 marker, pro-apoptotic Bax and anti-apoptotic Bcl-2 proteins during early development of the human tooth.

Materials and methods

Histological sections of eight human conceptuses, 5–10 postovulatory weeks old, were used for immunolocalization for Ki-67, Bax and Bcl-2 markers. Quantification was performed by calculating the fraction of Ki-67 positive cells, expressed as a mean ± SD, and analysed by Mann–Whitney test, Kruskal–Wallis and Dunn's post hoc test.

Results

In 6th–7th developmental weeks, the tooth germ and dental crest contained 37% of proliferating cells, which increased to 40% in the 8th week, and then decreased to 15% in the 10th week, whilst the proliferation in the ectomesenchyme subsequently dropped from 37% to 23%. Epithelial parts of the enamel organ displayed similar proliferation activity (31–36%), dental crest 10%, whilst enamel knot showed no proliferating activity. The tooth ectomesenchyme contained more proliferating cells (50%) than the jaw ectomesenchyme (35%), and both dropped to 28% in the 10th week. Ectomesenchyme between the tooth germs contained 23%, whilst the jaw ectomesenchyme contained 15% of proliferating cells. Bcl-2 expression had following pattern: strong in proliferating cells, moderate in tooth germs and dental crest, and weak in the ectomesenchyme. Bax co-expressed with Bcl-2 in the tooth germ and dental crest. In the reticulum and inner enamel epithelium Bcl-2 had prevalent expression, whilst Bax prevailed in the outer enamel epithelium and tooth ectomesenchyme.

Conclusions

Proliferating cells most likely influence growth of the tooth germ, Bcl-2 affects proliferation and differentiation of specific cell lineages, whilst Bax influences process of cell death.     

基于椎弓根三维形态测量实施个体化置钉技术

目的:观察胸腰段椎弓根CT测量在椎弓根螺钉内固定中的作用,寻找一种个体化椎弓根螺钉置入的方法。方法:选择1999-02/2006-03河北工程大学附属医院收治的T12和/或L1段骨折患者59例,行螺旋CT检查及图像三维重建,重建结束后,得到胸腰段标本的三维图像,通过旋转和切割进行图像处理并测量,模拟出T11～L2的椎弓根形态,根据CT测量椎弓根的实际投照点进行调整,即横断面上椎弓根轴线与矢状位上椎弓根轴线的交点,在确定进钉点时选择下关节突为参照物,选用合适直径的螺钉进行植钉,植入螺钉后,连接棒或板系统。结果:262个椎弓根行植钉术,242个完全在椎弓根内,仅有20个螺钉穿透椎弓根皮质。术后平均随访16.1个月,均无临床并发症的发生,Frankel平均增加1.4级。术后有2例患者出现断钉(3枚),1例患者出现断棒,所植入的螺钉与机体生物相容性好,无不良反应的发生。结论:利用三维CT测量的数据辅助,严格按照个体化的椎弓根的轴线方向植钉,在置钉时应考虑到螺钉本身直径的因素,可以提高植钉的成功率。     

颈动脉损伤大鼠新生内膜增生与局部平滑肌细胞的增殖

目的:观察大鼠颈动脉损伤后高同型半胱氨酸血症对新生内膜形成和局部炎症因子单核细胞趋化因子1、细胞间黏附分子1表达及局部平滑肌细胞增殖的影响。方法:实验于2004-10/2005-02在北京大学第一临床医院心血管研究所完成。①Wistar雄性大鼠50只,采用随机数字法分为蛋氨酸组:1g/(kg·d)L-蛋氨酸灌胃;对照组:饮用水灌胃,每组25只。4周后检测两组血浆同型半胱氨酸浓度,并行左颈动脉球囊拉伤,分别于3,7,14,28d取材,检测血管损伤后新生内膜增生和局部单核细胞趋化因子1、细胞间黏附分子1表达情况。结果:①两组大鼠血浆同型半胱氨酸浓度:蛋氨酸组血浆同型半胱氨酸浓度明显高于对照组[(106.19±19.75),(4.90±0.10)μmol/L]。②两组大鼠血管组织形态学观察结果:苏木精-伊红染色血管损伤后7d可见内膜增生,14,28d蛋氨酸组新生内膜增生厚度比对照组增加36%,33%;新生内膜面积增加41%,30%;内膜面积/中膜面积增加36%,21%;管腔面积减少47%,61%;两组间比较差异均有显著性,但中膜面积无显著性差别。蛋氨酸组14d血管内膜和中膜平滑肌细胞中增殖细胞核抗原阳性颗粒百分比是对照组的1.7倍和2.3倍[(84.40±9.05)%比(49.00±4.51)%,P<0.01;(53.30±5.25)%比(23.70±6.17)%,P<0.01]。未损伤的右颈总动脉两组血管内膜及中膜增殖细胞核抗原阳性颗粒数小于0.1%。蛋氨酸组血管损伤局部单核细胞趋化因子1、细胞间黏附分子1表达增强,单核细胞趋化因子1主要分布在新生内膜和中膜,细胞间黏附分子1主要分布在内皮下和新生内膜,3d,7d明显,持续28d。结论:高同型半胱氨酸血症上调血管损伤局部炎症因子单核细胞趋化因子1、细胞间黏附分子1表达,促使局部平滑肌细胞增殖,使新生内膜增生。     

Increased plasma N-glycome complexity is associated with higher risk of type 2 diabetes

Aims/hypothesis

Better understanding of type 2 diabetes and its prevention is a pressing need. Changes in human plasma N-glycome are associated with many diseases and represent promising diagnostic and prognostic biomarkers. Variations in glucose metabolism directly affect glycosylation through the hexosamine pathway but studies of plasma glycome in type 2 diabetes are scarce. The aim of this study was to determine whether plasma protein N-glycome is changed in individuals who are at greater risk of developing type 2 diabetes.

Methods

Using a chromatographic approach, we analysed N-linked glycans from plasma proteins in two populations comprising individuals with registered hyperglycaemia during critical illness (increased risk for development of type 2 diabetes) and individuals who stayed normoglycaemic during the same condition: AcuteInflammation (59 cases vs 49 controls) and AcuteInflammation Replication (52 cases vs 14 controls) populations. N-glycome was also studied in individuals from FinRisk (37 incident cases of type 2 diabetes collected at baseline vs 37 controls), Orkney Complex Disease Study (ORCADES; 94 individuals with HbA_1c > 6.5% [47.5 mmol/mol] vs 658 controls) and Southall and Brent Revisited (SABRE) cohort studies (307 individuals with HbA_1c > 6.5% [47.5 mmol/mol] vs 307 controls).

Results

Individuals with increased risk for diabetes type 2 development (AcuteInflammation and AcuteInflammation Replication populations), incident cases of type 2 diabetes collected at baseline (FinRisk population) and individuals with elevated HbA_1c (ORCADES and SABRE populations) all presented with increased branching, galactosylation and sialylation of plasma protein N-glycans and these changes were of similar magnitude.

Conclusions/interpretation

Increased complexity of plasma N-glycan structures is associated with higher risk of developing type 2 diabetes and poorer regulation of blood glucose levels. Although further research is needed, this finding could offer a potential new approach for improvement in prevention of diabetes and its complications.

     

Management of blunt pancreatic trauma in children

Purpose  Blunt abdominal trauma is the major cause of abdominal injury in children. Because of the retroperitoneal location, insidious signs and symptoms and the lack of sensitivity with common imaging modalities often lead to difficulties in making an accurate diagnosis. The most common complication is the formation of a pancreatic fistula, pancreatitis and a pancreatic pseudocyst, which usually manifests within 3 or 4 weeks after injury. Methods  The case records of seven children (4 male, 3 female) treated for blunt pancreatic injury in the department of pediatric surgery, University Hospital, Split were reviewed. Results  The treatment modalities were selected according to the grade of the pancreatic injury, hemodynamic status and associated injuries. Because all of the patients were classified as grade I or II according to the American Association for the Surgery of Trauma (AAST) classification, a conservative treatment was selected for all seven patients. In four patients the conservative treatment resulted in the total regression of the clinical, biochemical and radiological signs within four weeks (AAST grade I). In the other three patients, pancreatic pseudocysts arose within 3 or 4 weeks after the injury (AAST grade II). Conclusions  The status of the main pancreatic duct and the location of the pancreatic injury constitute the basis of the AAST scoring system. This scale should be used as a guide to selecting a surgical or conservative strategy. Based on these data, two factors appear to be the most important determinants of the treatment strategy for children with pancreatic injury: the grade of the pancreatic injury, which is determined according to the status of the main pancreatic duct and the clinical status of the patient.