Prophylactic antibiotics for head and neck surgery with flap reconstruction.

The leading cause of postoperative morbidity in patients undergoing major head and neck surgical procedures is postoperative infection. This prospective randomized multi-institutional clinical trial was designed to compare the effectiveness of clindamycin phosphate and high-dose cefazolin sodium therapy in preventing postoperative wound sepsis in patients undergoing contaminated head and neck surgical procedures in which flap reconstruction was required. Either clindamycin phosphate (900 mg) or cefazolin sodium (2 g) therapy was instituted intravenously prior to surgery and continued every 8 hours, for a total of 24 hours. The patients received postoperative follow-up, and the wounds were graded according to the worst condition observed. One hundred cases were evaluated. Fifty-one patients received clindamycin and 49 patients received high doses of cefazolin; wound infection developed in 10 patients (19.6%) and 11 patients (21.6%), respectively. This difference was not statistically significant. The average duration of surgery was approximately 8 hours for both the infected and the noninfected groups of patients. High-dose cefazolin and clindamycin have similar efficacy when administered prophylactically under these circumstances. Reconstruction with free vascularized tissue may aid in reducing postoperative wound infection.     

Benign giant cell tumor of bone with osteosarcomatous transformation (”dedifferentiated” primary malignant GCT): report of two cases

 It is not uncommon for sarcomatous transformation of giant cell tumor (GCT) of bone to occur after radiation, but rarely does malignant transformation occur spontaneously, with less than 15 cases reported up to 1995. Only four of these cases have been documented in detail. We report two additional cases of GCT of bone spontaneously transforming or ”dedifferentiating” into osteosarcoma without radiation therapy. The first case is absolutely unique and most interesting in that the dedifferentiation process occurred in one of multiple GCT lung metastases 6 years after successful eradication of a primary tibial tumor. The right lung was resected due to development of a large tumor, and at pathologic examination, demonstrated several small nodules of conventional GCT and a much larger, 14-cm mass composed of a mixture of GCT and high-grade osteosarcoma. The second case involved a physician, who had a large tumor in the sacrum with vague symptoms for 8 years. Open biopsy revealed conventional, benign GCT of bone with a secondary aneurysmal bone cyst. Complete curettage 2 weeks later revealed, in addition to areas of conventional, benign GCT a second component of very high grade osteosarcoma. Both patients died less than 1.5 years from diagnosis. This report of osteosarcomatous transformation of a conventional GCT of bone strengthens the theory that there is a mesenchymal cell line in GCT that may spontaneously tansform to sarcoma.     

Minimally invasive spinal surgery

Minimally invasive surgery offers quicker recovery and less morbidity for our patients through smaller surgical wounds and less tissue trauma. Although minimally invasive surgery has progressed in other fields of surgery for many years, spine surgeons have not previously embraced this philosophy for the various reasons discussed. However, minimally invasive spinal surgery has gained much interest in recent years. With the advent of new instrumentation, technology, and techniques, the promise of minimally invasive surgery in the spinal arena has become a reality. With the use of the microscope, navigational tools, newly developed canula for retraction, and image-guided percutenous pedicle screw systems, we can accomplish the same surgical procedures as currently used through smaller wounds and with greater precision. Nevertheless, all new technology does offer us an initial challenge of steep learning curves. Minimally invasive should not equate to minimal and inadequate treatment for our patients. Furthermore, careful analysis of this new technique is underway to assess its true advantages as compared with our current and proven techniques.     

DNA错配修复基因甲基化在肝细胞癌发生发展中的作用

目的探讨DNA错配修复基因(MMR)hMLH1,hMSH2和hMSH3甲基化在肝细胞癌(HCC)发生发展中的作用。方法采用甲基化特异性聚合酶链反应(MSP)法对38例新鲜HCC组织,相应非肿瘤肝组织,2例正常的捐肝组织及6种肝癌细胞系的hMLH1,hMSH2和hMSH3基因启动子CpG岛甲基化进行检测;培养6种肝癌细胞系,MSP法检测加入5-aza-2‘-deoxycytidine前后hMSH2基因在HCC中的甲基化状态改变;逆转录．聚合酶链反应(RT-PCR)方法检测加入5-aza-2’-deoxycytidine前后hMSH2在肝癌细胞株中的mRNA表达改变。结果HCC标本中13．2％(5／38)发生了hMLH1启动子甲基化,68．4％(26／38)发生了hMSH2启动子甲基化;相应的非肿瘤肝组织中hMLH1,hMSH2启动子甲基化阳性率分别为2．6％(1／38),55．3％(21／38);2例正常肝组织中未发现甲基化;6株肝癌细胞系中有5株发生了hMSH2启动子甲基化,而未发现有MLH1启动子甲基化。所有标本中均未发现有hMSH3启动子甲基化。5-aza-2‘-deoxycytidine处理细胞株后,可部分或完全逆转hMSH2启动子甲基化,各细胞株的mRNA均有不同程度的表达增加。结论hMSH3基因启动子CpG岛甲基化与HCC的发生发展关系不大。hMSH2基因甲基化与mRNA表达密切相关,是基因表达调节的一种重要方式。hMLH1和hMSH2基因启动子CpG岛的高甲基化在HCC中是一个常见的基因改变,DNA错配修复基因尤其是hMSH2基因启动子甲基化在HCC的发生中起了重要作用,是早期事件,其可能为临床诊断HCC提供新的检测指标。     

Two unusual benign lesions of the neck masquerading as malignancy on fine-needle aspiration cytology

Two cases of unusual benign tumors of the neck are described, both of which were initially misdiagnosed on cytology as carcinomas. Fine-needle aspiration findings in each case demonstrated a pleomorphic population of cells including bizarre multi-nucleated giant cells, the latter raising the false impression of malignancy. However, on review the cytological appearances of the tumors, a pleomorphic lipoma and a carotid body tumor, were characteristic. the correct diagnosis in each case would have been made or suggested if the pathologist had been familiar with the cytologic features characteristic of the lesion and the differential diagnosis of the head and neck tumors. in addition, the point is made that adequate clinical information is essential for the pathologist if all relevant conditions are not to be missed in the differential diagnosis.     

A controlled randomized response technique

The randomized response survey technique appears to be suitable for studies of sensitive sexual behaviors, particularly in AIDS-related research. However, existing methods provide only estimates of group statistics, not of individual information. Additionally, the popular "unrelated question" approach requires the knowledge of the parameters of the unrelated question. In this article, a variation of the unrelated-question method is suggested for use. Specifically, it is suggested that the unrelated question be one to which the response is known to be "yes." Through this "controlled" approach, the raw data become a direct linear transformation of the response to the sensitive question, and thus can be used directly in regression and other analyses at the individual score level. The estimation of the parameters for the unrelated question is not necessary and the hesitation to provide a "yes" response found in the "forced choice" method is minimized.     

Intracranial extension of inverted papilloma: An unusual and potentially fatal complication

BACKGROUND: The purpose of this article is to define the outcome of intracranial extension of inverted papilloma and outline a rationale for management of this rare clinical presentation. METHODS: A review of patients with intracranial extension of inverted papilloma reported in the literature (18 patients), or treated in our institution (3 patients ) was performed. The data of these 21 patients were consolidated with regard to clinical presentation, treatment, and outcome. Nine patients, including 1 of our cases, had coexisting squamous cell carcinoma and therefore were excluded from the analysis. Twelve patients with "pure" inverted papilloma formed the basis of this study. RESULTS: The majority of patients (83%) with intracranial inverted papilloma had recurrent disease. Patients with extradural disease had a survival rate of 86% with an average follow-up of 4.4 years. Eighty-six percent of these survivors were treated with craniofacial resection. In contrast, 75% of patients with intradural inverted papilloma were dead of disease with an average follow-up of 9.3 months regardless of the treatment modality. CONCLUSIONS: Intracranial extension of inverted papilloma is mostly associated with recurrent disease. Intracranial extradural inverted papilloma can be effectively controlled with craniofacial resection. Intracranial intradural involvement of inverted papilloma has a poor prognosis regardless of treatment. Aggressive treatment of intranasal inverted papilloma may be the most important factor in preventing intracranial presentation.     

Evidence of zinc deficiency in competitive swimmers

ObjectiveThe aim of this study was to assess the nutritional zinc (Zn) status of elite swimmers during different training periods.MethodsA longitudinal paired study was performed at the University of Sao Paulo in eight male swimmers 18 to 25 y old who had been swimming competitively at the state and national levels for at least 5 y. The swimmers were evaluated over a total period of 14 wk: before the basic and specific preparatory period (BSPP-baseline), at the end of the basic and specific preparatory period (post-BSPP), and at the end of the polishing period (PP). Levels of Zn were determined in the plasma, erythrocyte, urine, and saliva by atomic absorption spectrophotometry. Anthropometric measurements and a 3-d food record were also evaluated.ResultsThe median plasma Zn concentration was below the reference value in all training periods (BSPP-baseline 59 μg/dL, post-BSPP 55.9 μg/dL, after PP 58.8 μg/dL, P > 0.05), as were threshold values for erythrocytes (BSPP-baseline 36.5 μg of Zn/g of hemoglobin, post-BSPP 42 μg of Zn/g of hemoglobin, after PP 40.7 μg of Zn/g of hemoglobin, P > 0.05), urinary Zn (BSPP-baseline 280 μg/24 h, post-BSPP 337 μg/24 h, after PP 284 μg/24 h, P > 0.05), and salivary Zn (BSPP-baseline 66.1 μg/L, post-BSPP 54.1 μg/L, after PP 79.7 μg/L, P > 0.05). Salivary Zn did not correlate with plasma and erythrocyte Zn levels.ConclusionThe results suggest that the elite swimmers studied presented a possible Zn deficiency and that salivary Zn was not adequate to evaluate the Zn nutritional status.