Vascular complications in lumbar disk surgery: report of four cases

Vascular injuries in lumbar disk surgery, although rare, are serious complications which may be overlooked due to a broad range of clinical manifestations. It is important that surgeons and radiologists be aware of these potentially fatal complications and develop an appropriate symptom-based diagnostic paradigm. We reviewed 8099 consecutive cases of lumbar disk surgery, performed over a 14-year period at a single institution, for postoperative vascular complications. We identified four patients (0.05%) with lumbar disk surgery-related vascular complications: intraoperative lacerations of the abdominal aorta and median sacral artery, an arteriovenous fistula between the left common iliac artery and vein detected 19 days postdiskectomy, and a partially thrombosed aortic aneurysm with an arteriovenous fistula between the aneurysm and the inferior vena cava, diagnosed 11 months after surgery. The majority of cases in the literature of vascular injury in lumbar disk surgery were reported prior to 1965. Diagnostic approaches described in that period do not reflect the great range of diagnostic techniques available today. Angiography remains the gold standard for diagnosis and guidance as to surgical repair. However, a high index of suspicion based on clinical signs and/or the use of sonography or CT is important in the detection of these complications.     

Pseudoaneurysm: a complication of faulty technique in femoral arterial puncture

Pseudoaneurysm is a well-documented but rare complication of retrograde femoral arterial puncture. We present six patients in whom pseudoaneurysm complicated this procedure. The pseudoaneurysm arose from the superficial femoral artery in five patients and from the profunda femoris artery in one. An arteriovenous fistula also arose from the superficial femoral artery in one patient. In no patient did the pseudoaneurysm arise from the common femoral artery. Two mechanisms are postulated as to why pseudoaneurysms rarely complicate puncture of the common femoral artery.     

Cloning of glycoprotein IIIa cDNA from human erythroleukemia cells and localization of the gene to chromosome 17

Platelet aggregation requires the binding of adhesive proteins such as fibrinogen to the heterodimer of membrane glycoproteins IIb (GPIIb) and IIIa (GPIIIa). Human erythroleukemia (HEL) cells synthesize both GPIIb and GPIIIa. Using poly(A+) RNA purified from HEL cells, we constructed a cDNA library in the lambda gt10 phage vector. This library was screened with a 38mer oligonucleotide derived from a platelet GPIIIa peptide, and three overlapping cDNAs were isolated. The three inserts encompassed 3.5 kilobases (kb), including the entire coding region of mature GPIIIa (2,286 basepairs, bp) and 1.3 kb of 3' untranslated sequence. All 222 residues determined directly from platelet GPIIIa tryptic peptides exactly matched the HEL cell-deduced amino acid sequence. The HEL cell sequence matched a previously reported endothelial cell cDNA sequence except for eight nucleotides. Five of these nucleotide differences were silent changes consistent with genetic polymorphisms. The other three differences resulted in changes in the deduced amino acid sequence of GPIIIa; reexamination of the endothelial cell cDNA sequence in these three areas revealed that it is actually identical to the HEL cell sequence. The virtual identity of the endothelial and HEL cell cDNA sequences provides direct evidence that GPIIIa is a subunit common to cell-adhesion receptors present in more than one cell type. We localized the gene for GPIIIa to chromosome 17, the same chromosome to which we had previously mapped the gene for GPIIb.     

Acid phosphatase activity in mononuclear phagocytes and the U937 cell line: monocyte-derived macrophages express tartrate-resistant acid phosphatase

Tartrate-resistant acid phosphatase (TRAcP) is used as a marker for osteoclasts, which are believed to be derived from phagocytic cells or phagocyte stem cell precursors. To further investigate the relationship between monocytic phagocytes and osteoclasts, acid phosphatase (AcP) activity was measured by three different techniques in human peripheral blood monocytes, monocyte-derived macrophages, and the U937 cell line. We found that cytochemistry and gel electrophoresis led to similar results, but that the colorimetric assay was inconsistent. Normal human peripheral monocytes expressed both tartrate-sensitive and -resistant AcP. In culture these cells formed polykaryons and expressed TRAcP activity that was further identified as an isoenzyme associated with bone tissue. In contrast, the U937 cells did not express TRAcP activity as measured by gel electrophoresis. Both U937 cells and monocytes possess material that interferes with interpretation of the colorimetric assay of AcP. The presence of TRAcP in monocyte-derived macrophages further supports the relationship between phagocytic cells and bone osteoclasts.     

Severe congenital absence of skin in a preterm infant

A severe case of aplasia cutis congenita in a preterm infant is described. Although major problems with thermoregulation and fluid balance were anticipated, these parameters were relatively easy to control once the patient was stabilized. Meticulous skin care and rapid formation of a membranous-like fibrous tissue layer covering the denuded areas probably played an important role in minimizing excessive fluid and heat loss. The prognosis in aplasia cutis congenita is determined by the underlying associated anomalies, the severity of skin lesions and, in our case, the maturity of the infant who died from complications of prematurity.     

Neonatal Marfan syndrome: A case report

A case of neonatal Marfan syndrome is presented. The patient was noted to have cardiomegaly and tricuspid regurgitation on antenatal ultrasound scan. She was born with long, slender fingers and toes, an aged appearance and non-paralytic hypotonia. Echocardiogram revealed a dilated right atrium, right ventricle, dysplastic tricuspid valve and severe tricuspid regurgitation. She subsequently died of severe heart failure. Post-mortem examination showed the pathological features of lobar emphysema and cystic medial necrosis of the aorta. These features supported the diagnosis of neonatal Marfan syndrome. Nucleotide sequencing showed substitution of G by A at codon 1032 in exon 25 located in the long arm of chromosome 15. This resulted in the substitution of a cysteine by a tyrosine. A de novo mutation is suggested by the absence of affected family members.     

骺板软骨细胞的体外培养及鉴定

目的:建立体外培养及鉴定骺板软骨细胞的方法。方法:实验于2005-03/2006-05在苏州大学附属儿童医院骨科实验室完成。选用3只生后14～28d的新西兰幼兔,空气栓塞处死,暴露股骨下端和胫骨上端,分别取2处的骺板组织,将其剪切成1～3mm3的小块,经胰蛋白酶消化,接种于含150g/L牛血清的1640培养基中,饱和湿度培养,传代。①细胞接种后3h在倒置显微镜下观察细胞生长情况,见细胞贴壁后每天观察2次。②第2代细胞达到80%～90%左右汇合时采用常规苏木精-伊红染色,光镜观察细胞爬片情况。③第3代细胞爬片至细胞达到80～90%左右汇合时,采用苏木素染色3min,3%亮绿染色5min,蕃红花“O”染色5min,光镜观察细胞产生蛋白聚糖情况。④采用PCR检测细胞Ⅱ型胶原的表达。⑤采用四唑盐MTT比色法检测细胞活性。结果:①骺软骨细胞刚接种后呈大小不等之圆形悬浮于培养液中,3h后见大部分细胞贴壁,24h后贴壁细胞呈短梭形、圆形、三角形和不规则形,见细胞分裂相。48h后见细胞伸展明显,细胞分裂相每高倍镜视野可见多个。经隔日换液细胞生长至第5天,细胞呈聚集生长,达到汇合状态,将细胞传代。接种后第1代细胞2d后呈梭形,培养4d传至第2代,第2代细胞长满瓶底后,90%呈胞膜较厚的圆形,10%为梭形,第3代、第4代亦如此。传至第5代见肥大细胞增多,细胞松散,折光性减弱,呈凋亡状态。②细胞爬片后观察骺软骨细胞形态以梭形居多,同时也有圆形、三角形和不规则形。可见细胞分裂及细胞中的分泌小泡。③见细胞呈红色,无绿色,证明蕃红花“O”-亮绿染色阳性,显示所培养的细胞可以分泌蛋白聚糖。④PCR检测术所养细胞含有Ⅱ型胶原,电泳带在440bp上。⑤四唑盐MTT比色法检测显示,第3代骺软骨细胞的生长曲线近似倒“S”形,在第4,5,6天细胞呈对数生长,约在7,8,9,10d达平台期,至第12天细胞出现生长抑制。结论:建立了骺板软骨细胞的体外培养方法,并证实所培养出的细胞分泌蛋白聚糖和Ⅱ型胶原,具有软骨细胞的共同特点。     

Use of topical misoprostol to reduce radiation‐induced mucositis: Results of a randomized,double‐blind,placebo‐controlled trial

Radiation‐induced mucositis is an acute reaction of the mucosa of patients undergoing head and neck radiotherapy. It can have debilitating and dose‐limiting consequences. There is no consensus on an accepted intervention that significantly reduces its severity. Misoprostol is a synthetic prostaglandin E₁ analogue, with properties of a mucosal cytoprotectant. We designed a randomized, double‐blind, placebo‐controlled trial of misoprostol in patients with head and neck cancer. The aim of this study was to determine if topical misoprostol was effective in reducing the severity of radiation‐induced mucositis in patients receiving radical dose radiotherapy. The effect of this intervention on a patient’s general well‐being was also investigated. The primary end‐point of the study was the incidence of Radiation Therapy Oncology Group grade 3 mucositis. Between 1999 and 2002, 83 patients were recruited into the study at Westmead and Nepean Hospitals, Sydney. Forty‐two patients were randomized to receive misoprostol and 41 to receive a placebo. Most patients received radiotherapy in the adjuvant setting (52 of the 83) and had either an oral cavity (42 of the 83) or an oropharyngeal (16 of the 83) cancer. We could not identify any significant difference in the incidence of severe mucositis based on whether patients were allocated to receive misoprostol or placebo. There was no significant difference in the mean area under the mucositis curve (13.2 vs 16.6; P = 0.1). Patients allocated to misoprostol did report slightly increased soreness (7.6 vs 6.9; P = 0.04) and a greater use of analgesics. However, this difference did not translate into a worse feeling of general well‐being as measured by a simple visual analogue scale (5.8 vs 5.2; P = 0.3). In conclusion, we were unable to identify a reduction in radiation‐induced mucositis in patients receiving misoprostol. There is a paucity of high‐level evidence on potentially useful interventions and a continued need for new and innovative research, incorporating quality‐of‐life measurements, in patients experiencing radiation‐induced mucositis.