hTGF-β1基因增强组织工程化髓核修复退变腰椎间盘的实验研究

目的：探讨人转化生长因子-β1（hTGF-β1）基因修饰山羊骨髓基质干细胞（BMSCs）为种子细胞构建的组织工程化髓核对山羊退变腰椎间盘的修复作用。方法：用粗针穿刺山羊L1/2～L5/6纤维环抽取髓核制作椎间盘退变模型,同时体外培养山羊自体BMSCs并分为3组：实验组以携hTGF-β1基因重组腺病毒（Ad/hTGF-β1）转染;阴性对照组以携lacZ基因腺病毒（Ad/LacZ）转染,空白对照组为未转染细胞。抽取髓核后15d,收集3组细胞与透明质酸（HA）复合为组织工程化髓核,以细针从椎间盘原穿刺孔回植入髓核中央。L1/2至L3/4依次植入实验组、阴性对照组及空白对照组细胞;L4/5注入不含细胞的HA;L5/6不注入任何物质。术后观察24周,定期行放射学、组织学和生化检测。结果：X线片椎间隙测量显示,24周时L1/2～L4/5的椎间隙狭窄均较L5/6明显延迟（P〈0.05）;4周以内L2/3间隙的X-gal染色保持阳性;组织学评估示L1/2～L4/5退变均较L5/6为轻;免疫组化示L1/2在4周内高表达hTGF-β1、CollagenⅡ和Aggrecan,但8周后L1/2至L4/5未见显著性差异;GAG定量显示整个观察期内L1/2～L4/5均高于L5/6,其含量依次为L1/2〉L2/3=L3/4〉L4/5;对4周时L1/2至L3/4髓核组织的RT-PCR显示,L1/2的hTGF-β1、CollagenⅡ及Aggrecan的mRNA表达显著增强（P〈0.05）。结论：体外构建的组织工程化髓核回植可延缓椎间盘早期退变的进程,经hTGF-β1基因增强的组织工程化髓核对退变延缓作用尤为显著,但均无法完全逆转整个椎间盘退变进程。     

大块脱出腰椎间盘的组织学研究

目的通过对大块脱出腰椎间盘的组织学观察,探讨大块脱出椎间盘的组织学特征。方法对15例脱入椎管内的大块椎间盘组织常规石蜡切片制片,HE染色,普通光镜观察。结果初次手术的脱出椎间盘组织为单纯退变的髓核,术后复发的脱出椎间盘共有两种组织结构,分别是退变的纤维环和继发纤维化的髓核。结论采取措施防止残余髓核继发纤维化有可能可以作为防止椎间盘突出症术后复发的方法之一。     

实验性椎间盘退变的放射影像学与病理学观察

目的 研究椎间盘退变过程中，椎间盘退变的放射影像学与病理学改变。方法 选用40只新西兰大白兔随机分为2组，实验组切除兔腰椎间棘间、棘上韧带及棘突、关节突，造成力学失稳状态诱导形成椎间盘退变模型。术后一周、3个月、8个月时摄腰椎正、侧位X线片，观察腰椎影像学变化。第3个月、8个月时取腰椎间盘，进行组织检查，评定椎间盘退变的病理改变情况。结果 模型建立后，3个月、8个月的X线片显现对照组无明显改变，实验组腰椎后突畸形，椎间隙狭窄，随着时间延长椎体软骨终板钙化更加明显。组织学观察发现，实验组随术后时间延长，髓核由椎间盘内脱出，并伴有椎间盘两侧软骨终板的纤维化即软骨终板发生退变。结论 椎体软骨终板的退变是椎间退变早期的主要表现方式。     

髓核部分切除与全切除术后组织学与生物力学变化的比较研究

目的：比较髓核部分切除（ＰＮ）与髓核全切除（ＴＮ）对椎间盘组织学及腰椎间盘行：对犬腰椎间盘行ＰＮ与ＴＮ两种手术,在术后不同时间行光镜、电镜检查;术后３个月行生物力学测试。结果：术后椎间盘退变在ＴＮ组比ＰＮ组更明显,腰椎节段活动在ＴＮ组明显增加（Ｐ〈０．０１）,而ＰＮ组无明显增加（Ｐ〉０．０５）。结论：ＰＮ较之ＴＮ相对好地保存了椎间盘的生理功能,延缓了术后椎间盘退变的进程。     

腰椎间盘退变动物模型的建立

目的　建立腰椎间盘退变的动物模型并行组织学和MRI观察。　方法　健康成年恒河猴 8只 ,手术组 6只 ,在其腰4 ,5、腰5,6、腰6,7椎间盘分别作一 5mm× 3mm切口 ,分别于术前及术后 1、4、8、13、2 0周对手术椎间盘行MRI观察 ;8只恒河猴分别于术前 (对照组 )及术后 4、8、2 0周随机取 2只处死后行椎间盘组织学观察。　结果　正常成年恒河猴腰椎间盘组织学结构特点与人类相似 ;手术椎间盘高信号区域面积的百分比于术后 8、13、2 0周显著减少 (P <0 0 5 ) ;术后 4周椎间盘切口外被纤维组织覆盖 ,术后 8周 ,切口外层纤维样愈合 ,其内无愈合迹象 ,术后 2 0周 ,切口向椎间盘内延伸 ,部分髓核出现纤维化。　结论　恒河猴是一种生理特性与人类相接近的动物 ,以其为对象应用纤维环切开法可以获得可靠的腰椎间盘退变动物模型 ;通过测量MRI轴位T2加权像椎间盘高信号区域面积百分比的方法可于早期无损伤地发现椎间盘退变。     

CT引导下经皮纤维环穿刺建立兔腰椎间盘退变模型

【摘要】 目的：在CT引导下经皮纤维环穿刺建立兔腰椎间盘退变模型,并通过影像学和病理学验证其退变过程及效果。方法：3月龄新西兰大白兔18只,体重2.7~3.3kg,雌雄不限,术前均行X线及MRI检查。每只兔在螺旋CT引导下,用18G穿刺针经侧方皮下穿刺兔L5/6椎间盘（穿刺组）,确认刺入椎间盘纤维环深度约为5mm,并对L4/5椎间盘进行假性穿刺（穿刺达椎间盘边缘,但不刺入纤维环内;假穿刺组）,L3/4椎间盘作为对照椎间盘（对照组）。术后4周、8周、12周随机选取6只兔行X线片及MRI检查,观察各组椎间隙高度、邻近骨质改变及椎间盘信号改变,以“术后椎间隙高度/术前椎间隙高度×100”计算椎间盘高度相对值(DHRV),并进行椎间盘改良Thompson分级法分级;X线片及MRI检查结束24h内处死动物,选取对照、假穿刺和穿刺组椎间盘进行组织形态学及免疫组织化学分析。结果：对照组及假穿刺组术后4、8、12周,X线片示椎间隙高度无降低,无终板骨质硬化与骨赘形成;MRI T2加权成像图像示各椎间盘均呈高信号;组织学检查见髓核细胞数量较多,分布均匀,纤维环排列呈同心圆层状;免疫组化分析髓核呈Ⅰ型胶原染色强阳性,Ⅱ型胶原染色阴性,在各时间点表现无明显差别。穿刺组椎间盘在术后4周X线片即可见椎间隙高度轻度降低（DHRV=70.78±4.55）,MRI示椎间盘信号强度轻度下降,组织学上见纤维环结构紊乱、髓核细胞轻度减少;术后8周椎间隙高度明显降低（DHRV=50.63±4.04）,开始出现终板骨质硬化,MRI示椎间盘信号强度明显下降,组织学上髓核被胶原组织分裂为含较多椭圆形细胞的细胞岛,出现纤维软骨细胞,纤维环层状结构变形、部分断裂;术后12周椎间隙高度继续下降（DHRV=44.78±2.61）,骨赘形成、终板骨质硬化明显,MRI示椎间盘信号强度继续减弱,组织学上见髓核被纤维软骨组织所代替,纤维环层状组织碎裂、解体;免疫组织化学分析示术后4、8、12周髓核Ⅰ型胶原染色逐渐增强,Ⅱ型胶原染色逐渐减弱。各时间点对照组椎间盘的DHRV及改良Thompson分级与假穿刺组比较均无统计学差异（P＞0.05）;穿刺组在术后不同时间点的DHRV降低、改良Thompson分级增高与对照组及假穿刺组比较均有统计学差异（P<0.05）;随着穿刺时间的延长,穿刺组DHRV呈进行性降低趋势,改良Thompson分级进行性升高,两者在术后4、8、12周间均有统计学差异（P<0.05）。结论：CT引导下经皮纤维环穿刺法诱导兔椎间盘退变模型构建成功,操作方法简单、创伤小,经影像学及病理学证实其退变过程为渐进性。     

兔退变椎间盘中髓核细胞凋亡与BNIP3基因表达的意义

目的髓核细胞凋亡可能与髓核组织代谢障碍产生缺氧,导致BNIP3基因表达有关。通过观察兔退变椎间盘中髓核组织的细胞密度、细胞凋亡率及BNIP3的表达,为进一步了解髓核细胞凋亡机制提供实验依据。方法健康3月龄雄性新西兰大白兔30只,体重(2.3±0.2)kg,随机分为实验组(n=20)及对照组(n=10)。实验组大白兔采用针刺L3、4、L4、5及L5、6椎间盘制备椎间盘退变模型;对照组仅暴露椎间盘后缝合。术后4、8周通过MRI检查评价椎间盘退变情况,采用组织学观察和TUNEL法检查椎间盘髓核组织中凋亡细胞,用免疫组织化学染色法检测兔椎间盘髓核细胞BNIP3的表达。结果 MRI检查示实验组术后4、8周椎间盘髓核信号强度呈逐渐降低趋势。根据Pfirrmann分级标准,实验组术后4、8周椎间盘退变分级比较,差异均有统计学意义(P0.05)。组织学观察及TUNEL检查示:对照组椎间盘髓核中细胞密度高,可见少量散在的凋亡细胞;实验组术后4、8周时椎间盘髓核组织内细胞密度逐渐降低,可见较多凋亡细胞。各时间点实验组细胞密度、TUNEL染色阳性细胞率与对照组比较,以及实验组各指标两时间点间比较,差异均有统计学意义(P0.05)。对照组椎间盘髓核组织细胞中无BNIP3表达;实验组术后4、8周椎间盘髓核组织细胞中BNIP3表达逐渐增多,BNIP3染色阳性细胞率分别为13.45%±1.16%、32.00%±1.82%,BNIP3灰度值分别为194.32±4.65、117.54±2.11,各时间点间比较差异均有统计学意义(P0.05)。结论椎间盘退变与髓核组织中细胞密度下降有关,细胞凋亡是椎间盘髓核细胞减少的原因之一,BNIP3参与了椎间盘髓核细胞凋亡。     

微创针刺旋切制备兔椎间盘退变模型

目的探讨微创针刺旋切制备兔椎间盘退变(intervertebral disc degeneration,IDD)模型的可行性。方法取40只新西兰大白兔,雌雄不限,体质量(2.9±0.3)kg;随机分为对照组和实验组(n=20)。对照组不予处理;实验组采用18G穿刺针在C臂X线机引导下经皮侧后方穿刺进入L4、5、L5、6椎间盘内,旋切髓核组织以促进椎间盘的退变。术后4、8、12、16周行大体观察、MRI观察并根据Pfirrmann分级法评价椎间盘退变情况,然后处死动物取材行Masson染色和番红O染色观察。结果实验组髓核组织颜色较对照组暗,弹性降低。对照组MRI T2加权像椎间盘信号强度早期未见明显改变,后期略减弱;实验组椎间盘信号强度随时间延长呈减弱趋势。根据Pfirrmann分级法评价椎间盘退变程度,两组随时间延长椎间盘退变程度均逐渐加重(P0.05);两组间比较除术后4周差异无统计学意义(P0.05)外,其余术后各时间点实验组椎间盘退变程度较对照组严重(P0.05)。Masson染色示随时间延长,对照组纤维环出现排列不规整,但结构仍完整;实验组纤维环排列紊乱,甚至出现断裂现象。番红O染色示对照组髓核细胞未见明显减少,实验组髓核细胞明显减少。结论微创针刺旋切法可成功制备兔IDD模型。     

两种骨水泥渗漏对椎间盘影响的实验研究

目的 探讨椎体成形术时骨水泥渗漏是否会引起椎间盘退变，以及椎间盘退变程度与骨水泥类型是否相关。方法 选用8只成年家犬，以每只犬L2-3、L3-4、L4-5椎间盘为实验对象，随机分为对照组、聚甲基丙烯酸甲酯（polymethylmethacrylate，PMMA）与磷酸钙骨水泥（calcium phosphate cement，CPC）3组。对照组仅行椎间盘穿刺，不注入任何物质，PMMA组及CPC组均各向椎间盘注入0．1ml骨水泥。术前及术后24周摄正、侧位X线片，计算椎间盘高度指数百分数（disc height index percentage，DHIP）。术后24周行MR检查，计算MRI指数。组织学检查参照Masuda标准对椎间盘退变程度评分并分析。结果 术后24周X线片显示对照组椎间隙无狭窄，病理学检查未见椎间盘退变。PMMA、CPC组椎间盘MRI显示：椎间隙有狭窄，R加权像髓核信号不同程度降低且不均一，其相对高信号区面积减小，髓核形态不规则，纤维环与髓核界限不清。组织学检查显示髓核细胞数量不同程度减少，空泡变小。髓核的细胞外基质不同程度压缩，纤维环断裂或扭转。3组DHIP、MRI指数、组织学评分的差异均有统计学意义（P〈0.01）。结论 PMMA、CPC注入椎间盘会导致椎间盘退变，PMMA所致椎间盘退变较CPC更为严重.     

实验性椎间盘退变的放射影像学与病理学观察

目的　研究椎间盘退变过程中 ,椎间盘退变的放射影像学与病理学改变。方法　选用 4 0只新西兰大白兔随机分为 2组 ,实验组切除兔腰椎间棘间、棘上韧带及棘突、关节突 ,造成力学失稳状态诱导形成椎间盘退变模型。术后一周、 3个月、 8个月时摄腰椎正、侧位X线片 ,观察腰椎影像学变化。第 3个月、 8个月时取腰椎间盘 ,进行组织检查 ,评定椎间盘退变的病理改变情况。结果　模型建立后 ,3个月、 8个月的X线片显现对照组无明显改变 ,实验组腰椎后突畸形 ,椎间隙狭窄 ,随着时间延长椎体软骨终板钙化更加明显。组织学观察发现 ,实验组随术后时间延长 ,髓核由椎间盘内脱出 ,并伴有椎间盘两侧软骨终板的纤维化即软骨终板发生退变。结论　椎体软骨终板的退变是椎间退变早期的主要表现方式。     

Management of an infected pseudoaneurysm following an aortoventriculoplasty

An 11-year-old child developed prosthetic valve endocarditis with associated infection of the prosthetic and pericardial patches 6 months following an aortoventriculoplasty. Angiography revealed an associated false aneurysm which communicated with both the ascending aorta and the right ventricular outflow tract. This report discusses the surgical management of this patient.     

Graftskin Heals an Ulcer on an Amputation Stump

BACKGROUND: A 51-year-old man presented with a chronic ulcer of 28 years' duration on the amputation stump of his right foot. The prosthesis was aggravating the ulcer, despite multiple therapies. OBJECTIVE: To heal the ulcer and avoid a below-the-knee amputation. Graftskin, a bilayered living skin construct, was applied. METHODS: Graftskin was sutured in place following gentle debridement. Pentoxifylline was given to improve circulation. The dressing was changed 5 days after Graftskin application, then weekly for 7 weeks. RESULTS: Crusting was evident at 3 weeks, with an underlying white coating at 4 weeks. By 7 weeks, full reepithelialization was present under the crust and no ulceration remained. Over succeeding weeks the ulcer bed became flush with the surrounding skin. The patient's pain ceased, and some sensation and warmth returned to the stump. CONCLUSION: Graftskin treatment successfully healed a chronic ulcer, possibly preventing a more extensive amputation.     

Laparoscopic reduction of an ileoileal intussusception and resection of an inverted Meckel's diverticulum in an adult

Intussusception occurs commonly in children, but rarely is observed in adults. Whereas the hydrostatic pressure of a contrast enema often proves diagnostic as well as therapeutic in infants and children, resection usually is required for an underlying bowel pathology in older children and adults. Conventionally, the resection is accomplished at laparotomy. We report the case of a 20-year-old woman who presented with diarrhea and vomiting of 1 week duration. She was found unexpectedly to have intussusception on abdominal ultrasonography. The intussusception was laparoscopically reduced, and a segment of the middle small bowel that harbored an inverted Meckels diverticulum was resected laparoscopically, after which an intracorporeal anastomosis was fashioned. The ileus resolved on postoperative day 4, and the patient was discharged from hospital on postoperative day 5. The role of the laparoscopic approach in the management of intussusception is discussed.     

Infarction of an accessory spleen causing an acute abdomen

A case is presented of a five year old girl in whom an acute surgical abdomen developed due to torsion and infarction of an accessory spleen. Other similar cases in the literature are reviewed. The incidence, location, and embryologic aspects of accessory spleens are discussed. Infarction of an accessory spleen, although rarely the cause of an acute surgical abdomen, should be considered in the differential diagnosis.     

Development of an ankle-foot orthosis with an oil damper

The purpose of the present study was to develop an ankle-foot orthosis (AFO) that satisfies the requirements for an AFO for patients with hemiplegia as determined in a previous study. An oil damper has been introduced as an assistive device. The oil damper provides a resistive moment to plantar flexion of the ankle joint during initial stance on the paretic side. This function improves the insufficient eccentric contraction of the dorsiflexors. The magnitude of the resistive moment generated by this newly developed AFO can be changed easily to adjust its properties in accordance with the requirements of each patient. The mechanical properties of the AFO were measured, and the results showed that the AFO generated a sufficient resistive moment. Hemiplegic gaits with various types of AFOs were assessed, and it was found that the properties of the AFO affected the movements of the ankle, the knee, and the hip joints. The effects of the resistive moment on the alignment of the shank to the floor during initial stance are also discussed. Based on the results of this study, it is concluded that adjustability will be an essential feature for future AFOs.