Viscoelastic evaluation of fetal umbilical vein for reconstruction of middle cerebral artery

The transplantation of artificial blood vessels with 〈 6 mm inner diameter as substitutes for human arterioles or veins has not achieved satisfactory results. Umbilical vein has been substituted for ar- tery in vascular transplantation, but it remains unclear whether the stress relaxation and creep be- tween these vessels are consistent. In this study, we used the fetal umbilical vein and middle cere- bral artery from adult male cadavers to make specimens 15 mm in length, 0.196-0.268 mm in tu- nica media thickness, and 2.82-2.96 mm in outer diameter. The results demonstrated that the stress decrease at 7 200 seconds was similar between the middle cerebral artery and fetal umbilical vein specimens, regardless of initial stress of 18.7 kPa or 22.5 kPa. However, the strain increase at 7 200 seconds of fetal umbilical veins was larger than that of middle cerebral arteries. Moreover, the stress relaxation experiment showed that the stress decrease at 7 200 seconds of the fetal umbilical vein and middle cerebral artery specimens under 22.5 kPa initial stress was less than the decrease in these specimens under 18.7 kPa initial stress. These results indicate that the fetal umbilical vein has appropriate stress relaxation and creep properties for transplantation. These properties are advantageous for vascular reconstruction, indicating that the fetal umbilical vein can be transplanted to repair middle cerebral artery injury.     

Cavernous Transformation of the Portal Vein Causing Jaundice,Presenting in the Form of Wilson’s Disease

The following is a case review of portal vein cavernous malformation presenting with intermittent cholestasis and jaundice in a 4 year old child. Correct assessment was supported by radiology, later laparoscopy, yet hindered by histopathology representative Wilson’s disease and elevated urinary copper excretion. During surgical procedure the stenosis of the common bile duct secondary to extremely dilated portal vein reticulation was solved by Roux-en-Y choledochojejunostomy. After a one-year follow up the child remains asymptomatic.     

急性感染性门静脉血栓形成的临床分析

目的：探讨急性感染性门静脉血栓形成的临床特点及早期诊治方法。方法：回顾性分析中南大学湘雅二医院2003-2013年间收治的5例急性感染性门静脉血栓的临床资料。结果：5例患者均有腹部原发感染性疾病,超声检查发现门静脉血栓1例,增强CT检查发现5例。全部患者均予抗生素治疗,合用抗凝治疗3例。4例患者病情好转,其中2例血管部分或全部再通,1例因多器官功能衰竭放弃治疗。结论：急性门静脉血栓形成是腹部感染疾病少见但非常严重的并发症,早期表现为发热、腹胀、呕吐、腹泻,病情进展可有感染性休克、血性腹水、腹膜炎、肠梗阻或肠坏死、多器官功能衰竭;腹部超声及增强CT检查有助于早期确诊;积极抗感染、抗凝治疗并及时切除坏死肠段可有效实现血管再通及降低病死率。     

Lung transplant immunosuppression – time for a new approach?

Outcomes after lung transplantation remain worse compared to other solid organ transplants, which is in large part due to high rates of graft rejection. Despite emerging data that immune responses to lungs differ from other organs, immunosuppression for lung transplant recipients is still based on strategies established for recipients of other grafts. There exists an urgent need to develop immunosuppressive strategies for lung transplant recipients that take the unique immunological features of this organ into account.     

Retention of Stem Cell Plasticity in Avian Primitive Streak Cells and the Effects of Local Microenvironment

Primitive streak (PS) is the first structure occurring in embryonic gastrulation, in which the epiblast cells undergo the epithelial‐mesenchymal transition to become the loose mesoderm cells subsequently. Because the mesoderm cells departing from different portions of PS are blessed with disparate migration trajectory and differentiation fate, one question is when the cell fate is determinated. To understand whether the cell fate and cell migration pattern will be alternated along with the microenvironment transformation, the traditional transplantation technology was used to replace the anterior PS cells in HH4 host embryo using posterior PS tissue labeled by green fluorescent protein (GFP) in the same stage donor embryo, and then, we tracked the migration trajectory of the GFP‐positive cells with fluorescence stereomicroscope after incubation, and eventually verified the cell contribution from the transplants with in situ hybridization and immunocytochemistry. The same experimental strategy applied for posterior PS site replacement in host embryo. We found that the transplanted posterior PS cells to anterior part of streak followed the anterior PS cell migration pattern rather than kept its posterior streak cell migration trajectory, and so did vice versa. In addition, the transplants were involved in the contribution to the subsequent organogenesis as the local PS tissues affirmed by specific expression of myocardial or hematopoietic markers. Therefore, our data strongly suggest that the PS cells still keep stem cell plasticity during gastrulation and the eventual cell fate will depend on the spatial gene expression within local microenvironment along with development. Anat Rec, 296:533–543, 2012. © 2012 Wiley Periodicals, Inc.     

微型接骨板内固定结合自体松质骨移植治疗距骨颈粉碎性骨折

目的探讨切开复位微型接骨板内固定结合自体松质骨移植治疗距骨颈粉碎性骨折的手术方法及疗效。方法2010年1月~2012年1月,对我院收治的15例闭合性距骨颈粉碎性骨折患者,根据Hawkins分型：Ⅱ型11例,Ⅲ型4例。术前常规行CT三维重建明确骨折类型和粉碎程度,择期行切开复位微型接骨板内固定加自体松质骨移植术。术后定期复查X片及CT观察骨折愈合情况,并记录相关并发症,采用Hawkins评分标准评估疗效。结果本组14例获得随访,随访时间12~24m,,平均16.4m。术后外侧切口边缘部分坏死1例,经局部清创换药后治愈,无并发感染,骨折均在8~12w内获得愈合,平均愈合时间11.3w,无畸形愈合发生,距骨体部分坏死1例（Ⅲ型）,轻度创伤性关节炎3例（Ⅱ型1例,Ⅲ型2例）,末次随访时未发现内固定松动断裂。Hawkins评分：优7例（Ⅱ型）,良5例（Ⅱ型4例,Ⅲ型1例）,可2例（Ⅲ型）。结论采用切开复位微型接骨板内固定结合自体松质骨移植治疗距骨颈粉碎性骨折,术中可获得满意复位,牢靠的内固定可有效维持骨折复位,自体松质骨移植可促进骨折愈合,是治疗距骨颈粉碎性骨折的有效方法。     

肝静脉与门静脉的解剖及其在经颈静脉肝内门体分流术中的应用

目的：探讨肝静脉与门静脉的解剖及在经颈静脉肝内门体分流术（TIPS）中的应用。方法：在PUBMED、CNKI及维普等数据库中,查阅近年来国内外有关肝静脉、门静脉的正常解剖与变异及其在TIPS中应用的文献,进行分析总结。结果：肝静脉系统主要由肝右静脉、肝中静脉、肝左静脉3支组成,肝左静脉发生变异最多,肝中、右静脉变异相对少见。门静脉在肝门处进入肝脏,以分为左支和右支两主干这一类型居多,其解剖形态因地区、种族等因素而有差异。肝静脉和门静脉呈向后向上与向前向下的空间关系,经典TIPS是从肝右静脉距下腔静脉入口约2cm处向门静脉分叉部或右支内穿刺建立分流道。结论：肝静脉、门静脉的正常解剖与变异及其空间关系对顺利完成TIPS的操作至关重要。熟悉肝静脉、门静脉正常解剖和变异可提高TIPS的成功率,减少和避免并发症的发生。     

Anatomy of sodium hypochlorite accidents involving facial ecchymosis—A review

Objectives

Root canal treatment forms an essential part of general dental practice. Sodium hypochlorite (NaOCl) is the most commonly used irrigant in endodontics due to its ability to dissolve organic soft tissues in the root canal system and its action as a potent antimicrobial agent. Although NaOCl accidents created by extrusion of the irrigant through root apices are relatively rare and are seldom life-threatening, they do create substantial morbidity when they occur.

Methods

To date, NaOCl accidents have only been published as isolated case reports. Although previous studies have attempted to summarise the symptoms involved in these case reports, there was no endeavour to analyse the distribution of soft tissue distribution in those reports. In this review, the anatomy of a classical NaOCl accident that involves facial swelling and ecchymosis is discussed.

Results

By summarising the facial manifestations presented in previous case reports, a novel hypothesis that involves intravenous infusion of extruded NaOCl into the facial vein via non-collapsible venous sinusoids within the cancellous bone is presented.

Conclusions

Understanding the mechanism involved in precipitating a classic NaOCl accident will enable the profession to make the best decision regarding the choice of irrigant delivery techniques in root canal débridement, and for manufacturers to design and improve their irrigation systems to achieve maximum safety and efficient cleanliness of the root canal system.     

Slow Resorption of Anorganic Bovine Bone by Osteoclasts in Maxillary Sinus Augmentation

Purpose: Different biomaterials have been suggested for guided bone regeneration (GBR). These might show the ideal properties to let a new bone formation in the grafted area. Among these ideal features, it is essential their controlled resorption in order to be replaced for new vital bone. Bovine bone has been used widely as a good biomaterial for GBR, however there is still an interesting controversy about its resorbable capacity. In this sense, the objective of this study was to examine the behavior of anorganic bovine bone (ABB) in long‐term maxillary sinus graft healing and study its relationship with morphological and morphometrical variables. Materials and Methods: Seventeen maxillary sinus augmentation procedures were performed in patients. Bone cores were obtained from implant receptor sites at 6 months, 3 years, and 7 years of implant placement for histological, morphometric, and immunohistochemical (tartrate resistant acid phosphatase [TRAP]/cathepsin K/CD68) studies. Results: The percentages of bone, ABB particles, connective tissue, osteocytes, and osteoblasts in maxillary sinus grafts were similar at 6 months, 3 years, and 7 years. A progressive and significant decrease was detected in osteoclasts (p = .05, Kruskal‐Wallis test), TRAP and cathepsin K expression (p = .014 and p = .021, respectively), and osteoid lines (p = .038). Conclusion: According to these data, a decrease in osteoclasts over time may, partially, explain the ABB persistence observed in core biopsies. Further studies with more cases and different graft maturation times are required to elucidate the resorption rates and cell events underlying these phenomena.