Inhibition of proliferation and induction of apoptosis in SNU-1 human gastric cancer cells by the plant sulfolipid, sulfoquinovosyldiacylglycerol.

The sulfoglycolipid sulfoquinovosyldiacylglycerol is present in the membranes of photosynthetic organisms. This sulfolipid reportedly has pharmaceutical potential as an antiviral and antitumor agent, although no studies have examined these properties of the sulfolipids that are consumed in plant foods. This study examined the biological effects of sulfoquinovosyldiacylglycerol on the human gastric cancer cell line SNU-1. SNU-1 cells were grown in the absence and of presence of 1 &mgr;M, 100 &mgr;M or 1 mM sulfoquinovosyldiacylglycerol for up to 72 hours. Cell proliferation and viability were determined. The cells were analyzed for nuclear morphological changes by fluorescence microscopy and for DNAase-mediated DNA cleavage by flow cytometry and TUNEL detection. As indicated by cell number, the proliferation of SNU-1 cells by 72 hours of culture in the presence of 100 &mgr;M and 1 mM SQDG was inhibited 24 and 100%, respectively, as compared with the number of SNU-1 cells cultured in the absence of SQDG. Inhibition of cell proliferation by 100 &mgr;M sulfoquinovosyldiacylglycerol was in part associated with apoptotic cell death, as shown by changes in nuclear morphology and DNA fragmentation, whereas incubation of cells with 1 mM sulfoquinovosyldiacylglycerol caused necrotic cell death. Treatment of SNU-1 cells with sulfoquinovosyldiacylglycerol did not result in cell cycle arrest. The antiproliferative and apoptotic effects of sulfoquinovosyldiacylglycerol on SNU-1 gastric cancer cells revealed in this study suggest that this common dietary sulfolipid has intriguing potential as a chemopreventive or chemotherapeutic agent.

The role of the dentist in detection of carotid atherosclerosis.

Cerebrovascular accidents (CVA), or stroke, afflict 731,000 Americans each year, with 165,000 of these individuals dying. Stroke is a major cause of death and disability throughout the world, including southern Africa. Atherosclerosis-related formation of thrombi and emboli at the bifurcation of the common carotid artery and proximal internal carotid artery represents a common cause of stroke. The detection of carotid atherosclerosis by dentists using panoramic radiographs recently has been presented to the public through television news stories and the press, but many dentists still do not know how to interpret panoramic radiographs for detection of this condition. This communication illustrates examples in which carotid atherosclerosis was detected using panoramic radiography. Differential diagnoses are presented. Since not every carotid plaque calcifies, panoramic radiography should never be used alone to exclude the possibility of carotid atherosclerosis. It should also be remembered that the mere presence of calcified carotid plaque is not necessarily a reflection on the degree of carotid stenosis. Definitive diagnosis and treatment requires referral of patients deemed to be at risk to an appropriate physician. A variety of advanced diagnostic methods, including gadolinium-enhanced MRI, Duplex Doppler sonography and angiography are used to confirm carotid stenosis.

Discrimination between calcified triticeous cartilage and calcified carotid atheroma on panoramic radiography.

The differential diagnosis of calcified atherosclerotic plaque in the extracranial carotid vasculature includes a number of anatomic and pathologic radiopacities. Most of these are readily distinguishable on the basis of location and morphologic features. The calcified triticeous cartilage, however, can be a confounding alternative that is frequently misdiagnosed as a calcified atheroma. This paper describes the radiographic differences between these 2 entities, enabling clinicians to improve their diagnostic acumen when evaluating cervical soft tissue calcifications.

Evaluation of a training program for detection of carotid artery calcifications on panoramic radiographs.

OBJECTIVE: To evaluate the effectiveness of the American Academy of Oral and Maxillofacial Radiology-sponsored training packet for identification of carotid artery calcifications on panoramic radiographs. STUDY DESIGN: Two examiners, who completed the training (trainees), examined 778 panoramic radiographs. The sample included 298 men, with a mean age of 66, and 480 women, with a mean age of 68. Findings were compared with those obtained by an oral and maxillofacial radiologist. A kappa statistic was used to determine agreement between the 2 trainees. The positive predictive value (PPV) of the program was estimated by comparing the trainees rating of disease status with an expert in case identification. RESULTS: Examiners 1 and 2 identified 99 and 78 positive cases, respectively. A kappa statistic of 0.87 (95% CI, 0.81-0.92) was obtained, indicating good interexaminer agreement. The expert identified 27 positive cases, resulting in a PPV of 34.6% (95% CI, 24.4-46.3). CONCLUSION: Although the training packet offers valuable training, it does not provide a high PPV, suggesting the need to modify it or to seek an expert opinion before classification of a patient as having calcification on a panoramic radiograph.

Chewing gum affects smoking topography.

In a previous study, Wrigley's chewing gum was shown to reduce cravings to smoke and nicotine withdrawal when smokers were not allowed access to cigarettes. The present study expanded these findings by examining smoking behavior of 20 dependent cigarette smokers who were allowed free access to cigarettes throughout the study session but were encouraged and rewarded not to smoke. Each experimental session consisted of the participant watching a movie, then waiting an additional 30 min. Half of the participants were assigned to a gum condition in which they were asked to chew at least one piece of gum and had free access to chewing gum throughout the experimental session; half were assigned to a no-gum control. Results from this study indicate that when gum was present, participants took significantly fewer puffs and abstained for a longer period of time until their first cigarette. These results suggest that chewing gum may facilitate quit attempts.

Butyric acid and tributyrin induce apoptosis in human hepatic tumour cells.

The anti-colon cancer effect of dietary fibre results in part from its fermentation into the short-chain fatty acid butyric acid (BA) by intestinal microflora. BA has potent anti-colon cancer properties owing to its ability to induce apoptosis in colon cancer cells. The colon is not the only location where BA may reach high concentrations, because dietary BA is rapidly absorbed and transported to the liver. We have investigated whether BA could induce apoptosis in transformed human liver (Hep G2) cells. Hep G2 cells treated with BA displayed acetylated histones, increased DNA fragmentation and morphological features consistent with apoptosis. These biochemical features of BA-treated liver cells are identical to those of BA-treated colon cells. In addition, we investigated whether BA present in tributyrin, a triacylglycerol more compatible for inclusion into colloidal lipid structures than BA, could also induce apoptosis in Hep G2 cells. Tributyrin induced DNA fragmentation and morphological features characteristic of apoptotic cells in Hep G2 cells. These results are a significant advance towards delivering BA via colloidal lipid particles to cancerous sites in vivo. This study showed that BA and tributyrin are potent apoptotic agents, and we suggest that sources of dietary BA, such as milk fat, may provide anti-liver cancer properties.

Zygomatic air cell defect (ZACD). Prevalence and characteristics in a dental clinic outpatient population.

OBJECTIVES: To determine the prevalence and characteristics of zygomatic air cell defect (ZACD) among a general dental clinic population. METHODS: The panoramic radiographs of 2734 dental clinic outpatients were examined for the presence of ZACD. ZACD was defined as a nonexpansile, nondestructive cyst-like radiolucency in the zygomatic process of the temporal bone which appears similar to the mastoid air cells and which does not extend further anteriorly than the zygomaticotemporal suture. RESULTS: ZACD was found in 40 patients (1.5%) with a mean age of 49.6 (s.d. 18.0) years. Twenty cases (50%) each occurred in males and females. Meta-analysis of three large case series comprising 4579 patients revealed a total of 76 cases of ZACD (1.7% prevalence) occurring over an age range of 15-83 years. Thirty-four (44.7%) occurred in males while 42 (55.3%) occurred in females. Bilateral ZACD were found in 17 patients (22.4%). CONCLUSIONS: ZACD is not a rare anatomical variant, and clinicians planning eminectomy or other surgical procedures involving the zygomatic arch are advised to obtain appropriate presurgical imaging studies to avoid the need for creative intra-operative reconstruction.

Hyperaeration of the sphenoid sinus: cause for concern?

A case of exuberant pneumatization of the left sphenoid sinus into the pterygoid process and floor of the middle cranial fossa is presented. The fact that pneumatization of the sphenoid sinus is frequently atypical is of clinical import because there is an intimate relationship between the contents of a hyperaerated sinus and adjacent vital facial and cranial structures. It is imperative that clinicians determine the location and extent of the walls of the sphenoid sinus and its relationship to adjacent vital structures whenever endoscopic sinus surgery is contemplated to avoid morbid consequences during surgery.

Primary leiomyosarcoma of the mandible in a 7-year-old girl: report of a case and review of the literature.

Leiomyosarcoma is a malignant neoplasm of smooth muscle origin that manifests itself uncommonly in the oral cavity because of the paucity of smooth muscle in that location. To the best of our knowledge, only 10 cases of leiomyosarcoma primary to the jawbones have been reported in the English language literature. We report the first pediatric case of leiomyosarcoma arising from the mandible. Facial asymmetry and swelling were accompanied by a rapidly growing exophytic soft tissue mass that caused buccal displacement of the mandibular left permanent first molar. The lesion, observed radiographically as an extensive ill-defined area of osteolytic alveolar destruction, perforated the lingual cortex, displaced the inferior alveolar nerve canal inferiorly, and produced a "floating-in-air" appearance of the first molar. Diagnosis of leiomyosarcoma was made after initial incisional biopsy of the lesion. A 5-cm segmental mandibulectomy and supraomohyoid neck dissection were followed by reconstruction with a dynamic mandibular reconstruction plate and placement of a multidimensional mandibular distraction device in a transport rectangle of bone to promote bifocal distraction osteogenesis. Forty millimeters of distraction (the technical limit of the device) were performed; this was followed by terminal iliac crest bone grafting. Seventeen months after the definitive surgical procedure, the patient remains free of disease.

Docosahexaenoic acid accumulates in cardiolipin and enhances HT-29 cell oxidant production.

The objective of this study was to investigate membrane fatty acids for their effects on mitochondrial function in live cells. Mitochondrial potential and oxidant production were measured in human colonic adenocarcinoma (HT-29) cells with membranes enhanced in either oleic acid, linoleic acid, arachidonic acid, eicosapentaenoic acid, or docosahexaenoic acid. Docosahexaenoic acid-enriched cells had increased mitochondrial potential and produced 5-fold more cellular oxidants than did cells enriched with any other fatty acid. Oxidant production in fatty acid-enriched HT-29 cells did not correlate with the degree of unsaturation for total membrane fatty acids. However, there was a strong correlation between the degree of fatty acid unsaturation of cardiolipin, a critical inner-mitochondrial membrane phospholipid, and oxidant production. Cardiolipin acyl composition is known to influence the activity of electron transport complexes, an effect that can increase mitochondrial oxidant production. Docosahexaenoic acid was enriched to 48 mol% of the fatty acids present in HT-29 cell cardiolipin. These results demonstrate the importance of membrane acyl composition to mitochondrial potential and oxidant production in live cells. Additionally, results suggest that docosahexaenoic acid increases cell oxidant production by accumulating in cardiolipin, where its presence alters electron transport efficiency.

Seasonal variation in maxillary antral pseudocysts in a general clinic population.

OBJECTIVES: To determine overall prevalence of maxillary antral pseudocysts and the effect of seasonal variation, allergies, asthma and current smoking status. METHODS: Panoramic radiographs of 1175 dental clinic outpatients were examined. Data on the prevalence of allergies, asthma and smoking status was obtained from the medical records and age- and gender-matched controls. chi-square tests were used to determine the relationship between these factors and seasonal variation in prevalence. RESULTS: Pseudocysts were found in 114 (9.7%) patients. Eleven patients (9.7%) reported a history of environmental allergies, nine (7.9%) were asthmatic and 21 (19.6%) current cigarette smokers. Compared with controls, the association between each of these findings and the presence of pseudocysts was not significant. 44.3% of the pseudocysts were detected in November, December and January compared with only 8.6% in April, May and June: this variation was significant (alpha = 0.01). CONCLUSIONS: The marked increase in the prevalence of pseudocysts during cold winter months supports the concept that seasonal variation may be related to an increased incidence in viremias or irritation from dry forced air heating during this period.

The nature and extent of jaw involvement in Gaucher disease: observations in a series of 28 patients.

A wide variety of osteoarticular pathoses plague the clinical course of many patients with Gaucher disease. Osseous lesions involving the jaws have been described, usually as isolated case reports. The purpose of this study was to ascertain the nature and extent of mandibulo-maxillofacial pathosis in 28 patients with documented Gaucher disease by means of panoramic radiography. Twenty-five of the 28 patients displayed radiographic evidence of jaw involvement. The most prevalent finding was gross widening of marrow spaces; frank radiolucencies, endosteal scalloping, cortical thinning, root resorption, and inferior displacement of the mandibular canal or effacement of its cortices were also seen. A previously unreported finding was delayed eruption of permanent teeth, which was seen in more than one half of the patients who were under 20 years of age. Osseous changes throughout the jaws may be more common than previously suspected and may alert the dentist to the presence of the disease.

Carotid calcifications on panoramic radiography identify an asymptomatic male patient at risk for stroke. A case report.

Although stroke may be preventable, a major challenge is to find effective methods of detection of stroke-prone patients. Most noncardiogenic strokes occur as a result of atherosclerosis involving the proximal internal carotid artery, calcifications of which can be detected on dental panoramic radiography. This report describes the case of an asymptomatic patient whose dental radiographic findings led to carotid endarterectomy. Calcifications were viewed bilaterally in the soft tissues of the neck in the area of the carotid bifurcation on a screening panoramic radiograph of an asymptomatic 75-year-old man. Subsequent duplex Doppler ultrasound revealed extensive atherosclerotic changes bilaterally with critical stenosis (90%+) in the right internal carotid artery. Carotid digital subtraction angiography revealed a 95%+ stenosis at the origin of the right internal carotid artery. The patient underwent right carotid endarterectomy involving the internal, external, and common carotid arteries. Twelve months later the patient was alive and well. Dental panoramic radiography represents a useful imaging modality for detection of some asymptomatic stroke-prone patients. Identification of calcifications in the area of a patient's carotid vasculature should prompt expeditious referral to a physician for a cerebrovascular and cardiovascular work-up as part of an active stroke prevention strategy.

Use of panoramic radiography among an ambulatory dental population to detect patients at risk of stroke.

Panoramic radiographs of 3.6 percent of 1,175 newly accepted dental school patients displayed calcifications in the area of the carotid vasculature. The authors interviewed the patients with calcifications to determine whether they exhibited any recognized atherosclerosis, risk factors. One patient had symptoms of atherosclerosis, and a statistically significant correlation was found for obesity among the patients interviewed. The authors concluded that panoramic radiography is useful for identifying some asymptomatic patients with carotid calcifications. These patients should be referred to their physicians promptly for a cerebrovascular work-up as part of an active stroke-prevention strategy.

Diagnostic dilemma involving calcification in the parapharyngeal space: metastatic thyroid carcinoma masquerading as a deep lobe parotid mass.

As the parapharyngeal space is difficult to examine clinically, the radiographic distinction between deep lobe parotid masses and extraparotid tumors is essential in determining the surgical approach. We describe the case of a 53-year-old woman who presented with facial pain consequent to metastatic papillary thyroid carcinoma of the parapharyngeal space. A highly unusual pattern of calcification was present in the mass as observed by panoramic radiography and computed tomography. Parapharyngeal metastasis as the presenting feature of occult thyroid carcinoma has only been described four times previously in the medical literature.

Lateral periodontal cyst. Multifactorial analysis of a previously unreported series.

The objective of the present study was to review a series of 23 lateral periodontal cysts and 2 botryoid odontogenic cysts retrieved from the files of the State University of New York at Buffalo (SUNY) Oral Pathology Biopsy Service for epidemiologic characteristics as well as radiographic findings, clinical presentation, histopathologic features, and management. This study corroborated some previously established characteristics of the lesion but also revealed some surprising aberrations. A significant difference in the age range and mean age by gender was detected with the Student's t test within this population at the 0.05 level. The classic presentation of a lateral periodontal cyst seems to be that of an asymptomatic, small, ovoid, well-corticated radiolucency that occurs in an interradicular locus in the mandibular premolar segment of a middle-aged man. However, lateral periodontal cysts may manifest with pain and cause cortical perforation, may present as large expansile radiolucencies, may arise in the maxillary molar segment, and may develop in young females. Because of the tendency for aggressiveness of other lesions that may present with a similar picture, it is important to establish the final diagnosis of lateral periodontal cyst on a histologic basis in conjunction with the clinical and radiographic findings.

Relationship between wheelchair propulsion and independent walking in hemiplegic stroke.

BACKGROUND AND PURPOSE: We studied the relationship between wheelchair propulsion and final walking ability in hemiplegic stroke patients who were unable to walk independently 3 or more weeks after stroke. METHODS: Sixty hemiplegic stroke patients unable to walk independently 3 weeks or more after stroke were entered in a study comparing independent walking and wheelchair propulsion. Eight patients were lost to follow-up. Of the remaining 52 patients, 29 were entered 3 weeks and 23 were entered 4 to 10 weeks after stroke. Assessments were performed on admission and 4 and 14 weeks later. RESULTS: Fifteen of the 17 patients able to propel a wheelchair through a simple course at 3 weeks after stroke learned to walk independently (chi 2 = 9.94, P = .01), but none of the 12 who failed learned to walk (chi 2 = 12, P = .001). At the final assessment, the positive association between wheelchair propulsion and walking had been lost: 21 of 21 walkers and 18 of 31 nonwalkers could propel a wheelchair (chi 2 = 0.23, P = NS). The negative association remained: 13 of 31 nonwalkers failed the wheelchair test, but 0 of 21 walkers failed (chi 2 = 13.0, P = .001). Visual field deficits were significantly more common in patients unable to walk or propel a wheelchair than in walkers (chi 2 = 6.66, P = .01). Laterality had no effect on outcome. CONCLUSIONS: Ability to propel a wheelchair 3 weeks after stroke in hemiplegic patients unable to walk is the most accurate guide to walking potential that has been reported to date.