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JUNE 1998 617 THE JOURNAL OF PROSTHETIC DENTISTRY Osteoradionecrosis is a relatively infrequent complication found in patients who have received radiation therapy for treatment of head and neck cancer. The effects of cancerocidal irradiation on bone are well described and include osteocyte and osteoblast necrosis, marrow space fibrosis, periosteal fibrosis, and vascular endothelial death with hyalinization and thrombosis.1,2 The pathogenesis of osteoradionecrosis has been described by Marx3 to arise in irradiated bone as a result of the formation of a relatively hypoxic, hypovascular, and hypocellular tissue remnant that has a poor tolerance for metabolic, mechanical, or infectious insult. Bony and soft tissue degeneration, through collagen lysis and cellular death, exceeds the compromised capacity of tissue regeneration through collagen synthesis and cellular replication. Chronic nonhealing wounds may subsequently result from the inadequate supply of energy, oxygen, and structural precursors to the compromised irradiated tissue.3 Factors that may cause or exacerbate osteoradionecrosis in the jaws include higher-dose radiation, bacterial or fungal infection, poor postsurgical wound healing, preradiation and postradiation dental extractions, noncompliant dental hygiene, and prosthetic trauma.4-7 Despite maxillary bone inclusion in the radiation ports of many patients undergoing radiotherapy for oral cavity, sinonasal, and major and minor salivary gland malignancies, the incidence of osteoradionecrosis of the maxilla is reported to be less than 2% in contrast to the 3.6% to 37% range reported for the mandible.7,8 In the past decade, neutron beam radiotherapy has been advocated for both the primary and adjuvant treatment of inoperable or recurrent malignant tumors of the salivary glands, and adenoid cystic carcinomas of the paranasal sinuses, based on the reported higher local control rates, and acceptable reported cutaneous and soft tissue complication rates, in comparison to results of conventional photon radiotherapy.9,10 Adverse hard

The nuclear matrix has been linked to several important cellular functions within cells, such as DNA organization and replication, as well as regulation of gene expression. It has been reported that the nuclear matrix protein composition is altered in cells grown on different extracellular matrices in vitro. This study examined the nuclear matrix protein composition of tumors produced by MAT-LyLu (MLL) rat prostate tumor cells implanted at different organ sites within the rat. When high resolution two-dimensional gels were utilized to compare nuclear matrix protein composition to the prostate orthotopic tumor, it was found that there were distinct protein differences depending upon where the tumor grew. In particular, there were 14 proteins found in the lung, six proteins found in intramuscular, 17 proteins is the heart, and five proteins in the tail vein tumor tissue that were not present in the prostate orthotopic tumor tissue. Therefore, this study adds evidence to support that the nuclear matrix composition of a cell is dependent, at least in part, by the extracellular matrix and/or different cellular environments and may have a role in site-specific differences in tumor properties.

The progression of normal squamous epithelium to a malignant metastatic phenotype may depend on cellular genetic events and the failure of host mechanisms. Intermediate biomarkers are needed to more effectively identify and quantify malignant progression and develop the potential for specific treatments and prevention strategies. The nuclear matrix is the RNA-protein scaffold of the nucleus, which controls in part nuclear shape, DNA organization, and DNA function. Nuclear matrix proteins in all previously studied cell types show a common set of nuclear matrix proteins and a subset of tissue- and cell type-specific proteins. In every system studied to date, the nuclear matrix has been demonstrated to undergo quantifiable alterations in its protein composition with transformation to the malignant phenotype. The loss and gain of nuclear matrix proteins are being investigated as biomarkers for malignant transformation in breast, colon, and prostate carcinoma. We have investigated nuclear matrix protein composition in laryngeal and oral cavity primary squamous cell tumors and metastatic cervical lymph nodes. Laryngeal carcinoma demonstrated the gain of two specific nuclear matrix proteins in comparison with noncancerous squamous epithelium. Squamous cell carcinoma matrixes demonstrate greater heterogeneity than do previously studied adenocarcinoma matrixes, and yet they display specific matrix proteins that may represent important potential biomarkers.

Quantitative nuclear morphometry (QNM) provides a reliable, reproducible method for measuring the degree of nuclear pleomorphism, a qualitative parameter widely incorporated into histopathological grading schemes. Nuclear shape has successfully been shown to predict primary prostate adenocarcinoma metastatic potential. This investigation utilized QNM to measure the nuclear pleomorphism of 50 patients with primary laryngeal squamous cell carcinoma to determine whether this computer-assisted method could discriminate between those patients with and without cervical metastases. Nuclear cross-sectional area and nuclear roundness as determined by QNM could not discriminate between patients with and without cervical metastases, though significant alterations in nuclear morphology exist between normal laryngeal squamous epithelium and laryngeal squamous cell carcinoma.

Objective: We sought to test whether the use of the harmonic scalpel would cause less pain and more rapid recovery in tonsillectomy patients versus the use of electrocautery. Design and Setting: In a private practice community hospital, we conducted a prospective nonrandomized comparison of 156 pediatric tonsillectomy cases. Local anesthetic infiltrations and steroids were used at the discretion of the surgeon. Outcome variables consisted primarily of immediate- and mid-term pain, pain medications required, time to eating, morbidities and charges. Results: There were no differences between the groups on an intention-to-treat basis except for costs, which were higher in the harmonic scalpel group. When rescue use of electrocautery was required to control bleeding in the in the harmonic scalpel patients, more pain and longer times to taking food were noted. Conclusions: Used with discretion the harmonic scalpel is equivalent to electrocautery for tonsillectomy. Significance: The harmonic scalpel does not provide a major benefit over more conventional methods of tonsillectomy. (Otolaryngol Head Neck Surg 2002;127:333-8.)

To construct, propose, and evaluate the usefulness of a new clinical facial fracture classification scheme to accurately denote, communicate, and compare facial fractures.A retrospective, consecutive sample study with application of the proposed classification scheme to denote maxillary and zygomatic fractures with computed tomography.Metropolitan tertiary care trauma center.A total of 213 consecutive adult patients with facial fractures evaluated by means of 2-dimensional computed tomography.The classification scheme is defined according to fractures of vertical buttresses and horizontal beams. The scheme uses 3 primary descriptors of laterality and support sites to denote the clinical pattern of the fractures. This scheme was accurately applied and sufficient to describe 87 midfacial fracture patterns in this study. In addition, 118 (98%) of 120 mock fracture patterns were correctly transcribed and reproducibly communicated among 12 participating physicians.This newly proposed facial fracture classification scheme provides a convenient, specific, descriptive, and reproducible method of denoting fracture patterns. This scheme may be used to accurately communicate and compare, in greater detail than permitted using current independent classification schemes, the essential site and degree-of-severity characteristics of facial fractures critical to their surgical reduction and reconstruction. The usefulness of this classification scheme in determining optimal methods and subsequent outcomes in midfacial fracture reduction requires further investigation.

BACKGROUND Prostate cancer is the most common cancer diagnosed in U.S. men and remains incurable once it has metastasized. Many stages of the metastatic cascade involve cellular interactions mediated by cell surface components, such as carbohydrate-binding proteins, including galactoside-binding lectins (galectins). Modified citrus pectin (pH-modified), a soluble component of plant fiber derived from citrus fruit, has been shown to interfere with cell-cell interactions mediated by cell surface carbohydrate-binding galectin-3 molecules. PURPOSE The aim of this study was to determine whether modified citrus pectin, a complex polysaccharide rich in galactosyl residues, could inhibit spontaneous metastasis of prostate adenocarcinoma cells in the rat. METHODS The ability of modified citrus pectin to inhibit the adhesion of Dunning rat prostate cancer MAT-LyLu cells to rat endothelial cells was measured by 51Cr-labeling. Modified citrus pectin inhibition of MAT-LyLu cell anchorage-independent growth was measured by colony formation in agarose. The presence of galectin-3 in rat MAT-LyLu cells and human prostate carcinoma was demonstrated by immunoblotting and immunohistochemistry. One million MAT-LyLu cells were injected subcutaneously into the hind limb of male Copenhagen rats on day 0. Rats were given 0.0%, 0.01%, 0.1%, or 1.0% (wt/vol) modified citrus pectin continuously in their drinking water (from day 4 until necropsy on day 30). The number of MAT-LyLu tumor colonies in the lungs were counted. RESULTS Compared with 15 or 16 control rats that had lung metastases on day 30, seven of 14 rats in the 0.1% and nine of 16 rats in the 1.0% modified citrus-pectin group had statistically significant (two-sided; P < .03 and P < .001, respectively) reductions in lung metastases. The lungs of the 1.0% modified citrus pectin-treated rats had significantly (two-sided; P < .05) fewer metastatic colonies than control groups (9 colonies +/- 4 [mean +/- SE] in the control group compared with 1 colony +/- 1 in the treated group). Modified citrus pectin had no effect on the growth of the primary tumors. In vitro, modified citrus pectin inhibited MAT-LyLu cell adhesion to rat endothelial cells in a time- and dose-dependent manner as well as their colony formation in semisolid medium. CONCLUSIONS We present a novel therapy in which oral intake of modified citrus pectin acts as a potent inhibitor of spontaneous prostate carcinoma metastasis in the Copenhagen rat. IMPLICATIONS Further investigations are warranted to determine the following: 1) the role of galectin-3 in normal and cancerous prostate tissues and 2) the ability of modified citrus pectin to inhibit human prostate metastasis in nude mice.