Optical biopsy systems for the diagnosis and monitoring of superficial cancer and precancer

Histopathology is the gold standard in the diagnosis of cancer and dysplasia. Screening for the disease in high-risk populations(6,15) and choosing the correct site for biopsy have implications for the choice of follow-up intervals and therapy. Sully & Field(12) suggest that molecular genetic analysis, such as the polymerase chain reaction, for detecting progressive loss of heterozygosity, may be a more accurate predictor of the clinical course of oral cancer. This technique is now semi-automated and compares favourably with the time taken for histopathology (commonly 1-2 weeks). Recent developments suggest that the fluorescent and spectroscopic features may distinguish diseased from healthy tissue, and below follows an introduction for the clinician to this fascinating and complex field. It is possible to obtain a diagnosis in real-time and, with the appropriate use of photochemicals and image enhancement, it may be possible to treat and monitor the effects of treatment in real-time.     

Cellular neurothekeoma of the oral mucosa

Cellular neurothekeoma is an unusual benign neoplasm which, despite its name, is of uncertain origin. This report describes a cellular neurothekeoma of the cheek mucosa, the first at this site. The tumour presented in a 29-year-old man as a discrete mucosal thickening. Histology showed a generally well circumscribed, but unencapsulated, solid tumour which replaced the entire lamina propria and permeated between minor salivary glands and bundles of striated muscle in the submucosa. There was a sub-epithelial Grenz zone. The tumour was composed of nodules of pale, epithelioid cells separated by fascicles of spindle cells, with smaller strands and nests superficially. The nuclei were vesicular and, though mainly bland, occasionally atypical. The stroma was moderately infiltrated by mixed chronic inflammatory cells. Prominent nerves and blood vessels were seen at the periphery of the lesion, and neoplastic cells were noted within intact striated muscle fascicles. With immunohistochemistry, all the neoplastic cells strongly expressed NKI/C3, synaptophysin, neurone-specific enolase and vimentin, some expressed smooth muscle actin and PGP 9.5, but all were negative for S100, factor XIIIa, CD34, CD56, CD57, CD68, chromogranin A, desmin, epithelial membrane antigen and von Willebrand factor. The origin of the lesion is thus speculative. It was, however, completely excised and in 12 months there has been no recurrence.     

Further exploration of the effect of "diagnosis threat" on cognitive performance in individuals with mild head injury.

The present study further explored the phenomenon of "diagnosis threat" (Suhr & Gunstad, 2002), by examining the potential explanatory roles of anxiety, effort, and depression. Individuals with mild head injury history were randomly assigned to receive either neutral instructions (controls, N = 25) or to have attention called to their head injury history as a reason for invitation into the study (diagnosis threat, N = 28). Depression was measured at baseline. Following the neuropsychological battery, ratings of effort, test pressure, and state anxiety were completed. The diagnosis threat group performed worse than controls on attention/working memory, psychomotor speed, and memory tasks, but not on measures of executive functioning, post-test anxiety, or effort. Effort, anxiety and depression were not related to cognitive performance, nor did depression interact with expectations in explaining group differences in performance. Results provide further support for the "diagnosis threat" effect, but offer no support for effort, anxiety, or depression explanations for diminished performance.     

Signaling events during induction of plasminogen activator inhibitor-1 expression by sphingosylphosphorylcholine in cultured human dermal fibroblasts

Sphingosylphosphorylcholine (SPC) is a bioactive sphingolipid metabolite that can enhance wound healing. In a search for effectors downstream of SPC in the wound-healing process, we found that the expression of the gene for plasminogen activator inhibitor-1 (PAI-1) was significantly affected. ELISA and western blot analyses showed that SPC markedly induced PAI-1 production in human dermal fibroblasts cultured in vitro. Inhibition by pre-treatment with pertussis toxin (PTx), but not by tyrphostin A47 (a receptor tyrosine kinase inhibitor), indicated that PTx-sensitive G proteins were involved in SPC-induced PAI-1 expression. SPC elicited a rapid and transient increase in intracellular calcium levels ([Ca2+]i), measured using laser scanning confocal microscopy, which was partly mediated through PTx-sensitive G proteins. Pre-treatment with thapsigargin, but not with EGTA, abolished SPC-induced PAI-1 expression, indicating the importance of Ca2+ release from internal stores. Phorbol-12-myristate-13-acetate (PMA) induced the expression of PAI-1, and pre-treatment with Ro 31-8220 (a PKC inhibitor) markedly suppressed SPC-induced PAI-1 expression. SPC-induced PAI-1 expression was also significantly suppressed by PD98059 (a specific MAPK kinase 1/2 inhibitor). Consistent with this result, SPC stimulated the phosphorylation of p42/44 extracellular signal-regulated kinase (ERK). Together, these results suggest that SPC induces PAI-1 production through a G protein-coupled calcium increase and downstream kinase signaling events in cultured human dermal fibroblasts.     

Technical considerations in distraction osteogenesis

Five cases are presented to exemplify technical difficulties and complications which may be encountered when performing distraction osteogenesis in the facial skeleton. The procedure should be performed under close supervision by the surgical and orthodontic colleagues. Errors in the choice of vector may be managed by earlier removal of the distractor and subsequent traction on the previously osteotomized segments using orthodontic appliances and principles. Multiple distractors may be inserted in the same jaw and bimaxillary procedures are possible, increasing the likelihood of encountering technical difficulties. Detailed planning and close follow-up, with early recognition and active management of the complications, may be useful in ensuring a successful outcome of this versatile procedure.     

Effect of adult strabismus on ratings of official U.S. Army photographs.

PURPOSE: To determine if strabismus affects the ratings of official U.S. Army photographs. METHODS: Photographs of seven women and seven men officers (subjects) were digitally altered to give the impression of strabismus. Four photographs of each subject were obtained: two in an orthotropic state; one in a left exotropic state; and one in a left esotropic state. The photographs were presented randomly to a panel of 38 raters. Masked to the study design, the raters rated every photograph on a 1 to 10 Likert scale. The results were grouped according to eye alignment: two orthotropic groups, one exotropic group, and one esotropic group. Comparisons of the mean ratings were made between each eye alignment group and based on the subject's gender. RESULTS: The mean rating for each orthotropic group was 5.4 and 5.5 Likert scale units with a SD of 0.8 and 0.9, respectively (group 1 and group 2). The mean rating for the exotropic group was 5.4 Likert scale units with a SD of 0.7. The mean rating for the esotropic group was 5.1 Likert scale units with a SD of 0.8. Significantly lower ratings were obtained for the esotropic group compared with the orthotropic group (p=0.028). Women received significantly lower ratings regardless of eye alignment (p=0.044). CONCLUSIONS: This study indicates that the presence of esotropia negatively affects the rating of an official U.S. Army photograph; furthermore, female gender negatively affects ratings.     

Adaptive adjustment of the adolescent porcine mandibular condyle

The effect of occlusal support during primary dentition on the mandibular condyle remains controversial. We sought to determine whether unilateral loss of occlusal support leads to quantifiable adaptive changes of the condyle. Quantitative analysis of condylar growth and spongy bone volume after unilateral removal of teeth on the left side in adolescent minipigs was examined over a period of 4 months. Serial sagittal sections of the temporomandibular joint were examined using microradiography, fluorescence microscopy, and light microscopy. The condyles on the nonextracted side showed a higher growth rate than those on the extracted side, with a 1.56-fold thicker (p = 0.003) additional vertical bone layer. This factor was greater ventrally than dorsally (p = 0.0311), increasing from dorsomedial (1.33) to ventrolateral (2.38). There was therefore a reciprocal change of the condylar surface curve between the left and right condyles. Increased condylar growth correlated with a lower subchondral spongy bone volume (7.38% difference, p = 0.002). The amount of mineralized bone matrix generated was estimated to be about 1.33-fold higher in the nonextraction side condyles compared with those on the extraction side. Thus, unilateral loss of occlusal support was shown to lead to quantifiable alterations of condylar vertical growth and spongy bone volume in minipigs.     

Respiratory health among quartz-exposed slate workers--a problem even today

BACKGROUND: Quartz and dust are known to cause respiratory problems. Slate workers in Alta, Norway are exposed to these compounds even today, and the need for improvement of their work environment was evaluated. METHODS: Respiratory health was examined using chest X-ray, lung function tests and a self-administered questionnaire in a cross-sectional study. RESULTS: The prevalence of silicosis among the slate workers varied between 1.9 and 6.5%. The slate workers had significantly more respiratory symptoms than the controls when adjusted for smoking. Peak expiratory flow was significantly lower among slate workers than among controls. CONCLUSION: The work environment of the slate workers may cause adverse effects in their airways. Improvements to their work environment are indicated.