Heterogenecity of fibroblasts.

Fibroblasts are a major stromal cell type present in human connective tissue maintaining the structural integrity in health. Depending on the situation, location and various conditions, fibroblasts exhibit considerable variation in morphology, size and shape that suggest the existence of discrete cellular subsets. The purpose of this short communication is to provide information regarding the heterogenecity of fibroblasts and its variability in physiological and pathological conditions.

Occlusal plane orientation: a statistical and clinical analysis in different clinical situations.

PURPOSE: Orientation of the occlusal plane is important in a number of clinical situations. Using the reported soft and hard tissue landmarks is difficult and requires experience, as the landmarks are located on the face or by use of a cephalometric radiograph. Improper use of these landmarks may compromise the functional and esthetic result of prosthetic restorations. This study evaluated the reliability of the hamular notch/incisive papilla plane (HIP) in establishing the occlusal plane. MATERIALS AND METHODS: Ninety healthy, Indian adults (60 dentate, 30 edentulous) participated in this study. The occlusal plane of the subjects was compared with their HIPs. In dentate subjects, the maxillary stone cast was mounted on the Wills surveyor with HIP, which was made parallel to the horizontal plane using the tripoding method. The vertical distance between the occlusal plane and floor of the surveyor was measured at four points. When the measured values were equal, the two planes were confirmed to be parallel for that situation. In turn, this relation confirmed the parallelism between the occlusal plane and HIP. In the edentulous subjects, the occlusal plane, established clinically using the ala tragal line, was compared with the HIP radiographically using lateral cephalograms. Paired t-test was used to test the equality of the mean differences at a 0.05 significance level. RESULTS: The mean differences from the right canine were: 0.055 cm at the left canine, 0.05 cm at the right molar, and 0.065 cm at the left molar in dentate subjects and 0.001 cm between the incisive papilla and hamular notch in edentulous subjects. The HIP appeared parallel to the occlusal plane as the paired t-test showed no statistically significant difference (p > 0.05). CONCLUSION: In the population tested, the HIP was parallel to the occlusal plane. Therefore, this may be a viable reference in complete denture prosthodontics.

Unusual presentation of nasopharyngeal (juvenile) angiofibroma in a 45 year old female.

Juvenile nasopharyngeal angiofibroma is a rare tumour, comprising 0.05% of the head and neck tumours, histologically benign, locally invasive, and has a specific predilection for nasopharynx and adolescent males. This article presents an unusual case of nasopharyngeal angiofibroma in a 45-year-old female patient, manifesting as a destructive maxillary lesion and discusses the two most important factors regarding this tumour, the etio-pathogenesis and spread.

Canalicular adenoma of the upper lip mimicking mucocele.

Salivary gland neoplasms are relatively rare. Among the salivary gland neoplasms minor salivary gland neoplasms are often deceptive to the clinician and challenging to the pathologist because of their varied morphology and diverse histopathological pattern. This article documents a case of canalicular adenoma of the upper lip mimicking mucocele and discusses the differential diagnosis of minor salivary gland neoplasms.

Analysis of glycoconjugates in patients with oral squamous cell carcinoma.

BACKGROUND: Our aim was to examine the levels of glycoconjugates in plasma, erythrocyte membranes and buccal mucosa of healthy subjects and oral cancer patients. SUBJECTS AND METHODS: This study was conducted on 48 adult male oral cancer patients with various clinical stages (stage II to stage IV; 16 of each) and 16 disease-free healthy subjects who underwent surgical removal of impacted teeth or vestibuloplasty without inflammation. RESULTS: The plasma and tumor tissues glycoconjugates levels were significantly increased, whereas the erythrocyte membranes glycoconjugates were significantly decreased in oral cancer patients as compared to healthy subjects. The levels of glycoconjugates were gradually increased from stage II to stage IV in plasma and tumor tissues and decreased in erythrocyte membranes from stage II to stage IV of oral cancer patients. CONCLUSION: The increased plasma glycoconjugates can be due to the expense of erythrocyte membrane glycoconjugates or tumor tissue itself.

Biochemical changes in tumor tissues of oral cancer patients.

OBJECTIVES: Our aim was to assess the oxidative stress in tumor tissues of oral cancer patients by measuring the levels of lipids, thiobarbituric acid reactive substances (TBARS) and antioxidants. DESIGN AND METHODS: This study has been conducted on oral tumor tissues of 48 adult male oral cancer patients with various clinical stages (stage II to stage IV; 16 of each) and normal tissues of an equal number of age and sex matched disease free healthy subjects. The levels of lipids, lipid peroxidation and antioxidants in buccal mucosa of healthy subjects and oral cancer patients were assayed using colorimetric methods, except for vitamin E (fluorometriy). RESULTS: Total cholesterol and esterified cholesterol were markedly increased whereas phospholipids and free fatty acids were significantly decreased in tumor tissues as compared to normal tissues. The decrease in TBARS levels and functional compromise of antioxidant defense mechanisms were observed in the tumor tissues as compared to normal subjects. CONCLUSIONS: The low availability of peroxidizable substrates and the enhanced antioxidant capacity in tumor tissues make them less susceptible to oxidative stress, conferring a selective growth advantage on tumor cells.

Sequential Changes in the Cellular Redox State During 7,12-Dimethylbenz[a]anthracene-Induced Carcinogenesis in the Hamster Buccal Pouch.

Our objective was to elucidate sequential changes in the oxidant-antioxidant status during 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis. In designing the study, we divided hamsters into experimental and control groups. The right buccal pouches of the experimental animals were painted three times a week with a 0.5% solution of DMBA in liquid paraffin. The control animals received paraffin alone. The hamsters were killed after 1, 4, 8, 12, and 16 weeks of DMBA treatment, and the buccal pouches were examined for histopathological changes. The extent of lipid peroxidation and the status of glutathione-dependent antioxidants were evaluated in the buccal pouch, liver, and erythrocytes. Our results showed that the experimental animals developed severe hyperplasia and hyperkeratosis after 4 weeks, dysplasia after 8 weeks, and well-developed squamous cell carcinomas after 16 weeks of DMBA application. Topical application of DMBA increased lipid peroxidation in the buccal pouch up to the 8th week; there was a substantial fall after 12 weeks and significantly low levels after 16 weeks. This was accompanied by a sustained increase in reduced glutathione (GSH) and the activities of glutathione peroxidase (GPx), glutathione-S-transferase (GST), and gamma-glutamyltranspeptidase (GGT) throughout the carcinogenic progression. However, in the liver and erythrocytes, the concentrations of lipid peroxides were higher, and GSH- and GSH-dependent enzyme activities were lower than in the controls throughout the experiment. This study has revealed intrinsic differences in the cellular redox state in the target organ and host tissues of tumor-bearing animals. We suggest that measurement of lipid peroxidation and GSH-dependent antioxidants could be valuable in evaluating carcinogenic progression and the effects of putative chemopreventive agents in the hamster buccal pouch model.

Oxidant-antioxidant status in patients with oral squamous cell carcinomas at different intraoral sites.

OBJECTIVES: To compare the extent of lipid peroxidation and the status of antioxidants in tumor and venous blood of patients with oral squamous cell carcinoma (OSCC) at different intraoral sites. DESIGN AND METHODS: Twenty four patients with OSCC at different intraoral sites and an equal number of age- and sex-matched reference subjects were chosen for the study. The concentrations of lipid peroxides and reduced glutathione (GSH) and the activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) were estimated in tissues and blood. RESULTS: Diminished lipid peroxidation in tumor tissue was accompanied by decreased activities of SOD and CAT with increase in GSH and GSH-dependent enzymes. In contrast, enhanced lipid peroxidation with decrease in antioxidants was observed in the venous blood of OSCC patients. CONCLUSION: No significant differences in lipid peroxidation and antioxidant levels were observed between patients with OSCC at different intraoral sites. However, our results revealed differences between the tumor and blood with respect to their susceptibility to lipid peroxidation and antioxidant status.

Chemopreventive efficacy of lycopene on 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis.

The chemopreventive efficacy of lycopene on 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis was examined using lipid peroxidation, reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione S-transferase (GST) and glutathione reductase (GR) as biomarkers of chemoprevention. Twenty four male Syrian hamsters were divided into four groups of six animals each. The right buccal pouches of the animals in group 1 were painted with a 0.5% solution of DMBA in liquid paraffin three times a week. The animals in group 2 were painted with DMBA as in group 1 and in addition received 2.5 mg/kg body weight lycopene orally three times a week on days alternate to DMBA application. Group 3 animals received lycopene as in group 2. Animals in group 4 received neither DMBA nor lycopene and served as control. The hamsters were killed after an experimental period of 14 weeks. Biochemical measurements were carried out in tumour and normal tissues. All hamsters painted with DMBA alone for 14 weeks developed well-differentiated squamous cell carcinomas. Diminished lipid peroxidation in the oral tumour tissue was accompanied by a significant increase in the levels of GSH, GPx, GST and GR. Administration of lycopene significantly suppressed DMBA-induced oral carcinogenesis as revealed by the absence of carcinomas. The results of the present study suggest that lycopene may exert its chemopreventive effects by modulating lipid peroxidation and enhancing the activities of the enzymes in the glutathione redox cycle.

Prevention of 4-nitroquinoline 1-oxide-induced rat tongue carcinogenesis by garlic.

The present study was undertaken to examine the inhibitory effect of garlic (Allium sativum) on 4-nitroquinoline 1-oxide (4NQO)-induced tongue carcinogenesis in male rats, both in the initiation and post-initiation phases. Lipid peroxidation, reduced glutathione (GSH), glutathione peroxidase (GPx), and glutathione S-transferase (GST) were used to monitor the chemopreventive potential of garlic. Biochemical estimations were carried out on tumour and normal tongue tissues. Diminished lipid peroxidation in the tumour tissue was accompanied by a significant increase in the levels of GSH, GPx and GST. Administration of garlic (250 mg/kg, p.o., three times a week) effectively suppressed 4NQO-induced tongue carcinogenesis as revealed by the absence of carcinomas in the initiation phase and their reduced incidence in the post-initiation phase. The results of the present study suggest that garlic may exert its chemopreventive effects by modulating lipid peroxidation and enhancing the levels of GSH, GPx and GST.

Coffee enhances the development of 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch carcinomas.

UNLABELLED: In this study, we examined the effect of roasted coffee extract on 7,12-dimethylbenz[a]anthracene (DMBA)-induced buccal pouch carcinogenesis in male Syrian hamsters using lipid peroxidation, reduced glutathione (GSH) and glutathione peroxidase (GPx) activity as biomarkers of chemoprevention. Forty male hamsters were divided into four groups of 10 animals. The right buccal pouches of the animals in Group 1 was painted with a 0.5% solution of DMBA in liquid paraffin three times a week. The animals in Group 2 painted with DMBA as in Group 1, received in addition 2 ml of 8% black coffee extract intragastrically three times a week on days alternate to DMBA application. Group 3 animals received coffee extract as in Group 2. Animals in Group 4 received neither DMBA nor coffee extract and served as control. The hamsters were sacrificed after an experimental period of 14 weeks. Biochemical measurements were carried out on tumour and normal pouch tissues. Administration of roasted coffee extract had no preventive effect on DMBA-induced oral cancer as revealed by the higher mean tumour volume and tumour burden compared to animals painted with DMBA alone. Diminished lipid peroxidation in the oral tumour tissue was accompanied by a significant increase in the levels of GSH and GPx. CONCLUSIONS: The results of the present study suggest that coffee exerts a tumour enhancing effect when administered during DMBA-induced hamster buccal pouch carcinogenesis.

S-allylcysteine, a garlic constituent, inhibits 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis.

The effect of S-allylcysteine (SAC), a water-soluble garlic constituent, on 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis was investigated in male Syrian hamstes. Forty hamsters were divided into 4 groups of 10 animals. The right buccal pouches of the animals in Group I were painted with a 0.5% solution of DMBA in liquid paraffin three times a week. The animals in Group II were painted with DMBA as in Group I and, in addition, received 200 mg/kg body wt p.o. SAC three times a week on days alternate to DMBA application. Group III animals received SAC as in Group II. Group IV animals received neither DMBA nor SAC and served as the control. The hamsters were killed after an experimental period of 14 wk. Measurement of lipid peroxidation, the antioxidant enzymes superoxide dismutase (SOD) and catalase, in the buccal pouch mucosa, liver, and circulation was used to monitor the chemopreventive potential of SAC. All hamsters painted with DMBA alone developed tumors identified histologically as well-differentiated squamous cell carcinomas. In hamsters bearing DMBA-induced buccal pouch tumors, diminished lipid peroxidation in the tumor tissue was accompanied by decreased activities of SOD and catalase, whereas in the liver and circulation, enhanced lipid peroxidation was associated with compromised antioxidant defenses. Administration of SAC suppressed the incidence of DMBA-induced HBP tumors as revealed by the absence of carcinomas. Histologically, only keratosis was observed. SAC modulated DMBA-induced decreased susceptibility of the HBP to lipid peroxidation while simultaneously enhancing SOD and catalase activities, whereas in the liver and circulation, SAC decreased the extent of lipid peroxidation and significantly enhanced antioxidant activities. We suggest that SAC exerts its chemopreventive effects by modulating lipid peroxidation and enhancing antioxidant activities in the target organ as well as in the liver and circulation.

Of humans and hamsters: comparative analysis of lipid peroxidation, glutathione, and glutathione-dependent enzymes during oral carcinogenesis.

We examined the extent of lipid peroxidation and the amount of reduced glutathione (GSH), and activities of the GSH-dependent enzymes, glutathione peroxidase (GPx) and glutathione S-transferase (GST), in human oral tumour tissue and 7, 12-dimethylbenz[a]anthracene-(DMBA)-induced hamster buccal pouch tumour tissues. Diminished lipid peroxidation in the oral and hamster tumours was accompanied by a significant reduction in the concentration of phospholipids and an increase in the cholesterol:phospholipid ratio. The concentration of glutathione and the activities of GPx and GST were raised in both human oral and hamster tumour tissues. Our results show that the patterns of changes in human oral squamous cell carcinomas and chemically-induced carcinomas of the hamster buccal pouch are similar.

Effects of garlic on 7,12-Dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis.

The inhibitory effect of garlic (Allium sativum Linn) on 7, 12-dimethylbenz[a]anthracene (DMBA)-induced buccal pouch carcinogenesis was investigated in male Syrian hamsters. Measurement of lipid peroxidation, reduced glutathione (GSH), glutathione peroxidase (GPx), and glutathione S-transferase (GST) was used to monitor the chemopreventive potential of garlic. All hamsters painted on their buccal pouches with DMBA alone for 14 weeks developed well-differentiated squamous cell carcinomas. Diminished lipid peroxidation in the oral tumor tissue was accompanied by a significant increase in the levels of GSH, GPx, and GST. Administration of 250 mg/kg body weight aqueous garlic extract three times a week for 14 weeks effectively suppressed DMBA-induced oral carcinogenesis as revealed by the reduced incidence of neoplasms. The results of the present study suggest that garlic may exert its chemopreventive effects by modulating lipid peroxidation and enhancing the levels of GSH, GPx, and GST.

Chemopreventive potential of neem (Azadirachta indica) on 7,12-dimethylbenz[a]anthracene (DMBA) induced hamster buccal pouch carcinogenesis.

The inhibitory effect of the aqueous extract of neem (Azadirachta indica A. Juss.) on 7,12-dimethylbenz[a]anthracene (DMBA) induced buccal pouch carcinogenesis was investigated in Syrian male hamsters. All hamsters painted on their buccal pouch with DMBA for 14 weeks developed squamous cell carcinoma. Administration of neem leaf extract effectively suppressed oral carcinogenesis initiated with DMBA as revealed by the reduced incidence of neoplasms. Lipid peroxidation, glutathione (GSH) content and the activities of glutathione peroxidase (GPx), glutathione S-transferase (GST) and gammaglutamyl transpeptidase (GGT) were used to biomonitor the chemopreventive potential of neem. Lipid peroxidation was found to be significantly decreased, whereas GSH, GPx, GST and GGT were elevated in the oral mucosa of tumour bearing animals. Our data suggest that neem may exert its chemopreventive effects in the oral mucosa by modulation of lipid peroxidation, antioxidants and detoxification systems.

Fine needle aspiration cytology as a diagnostic test for oral squamous cell carcinoma.

OBJECTIVE: The purpose of this study was to determine the possibility of using fine needle aspiration cytology (FNAC) as a primary diagnostic test in oral leukoplakia and squamous cell carcinoma. MATERIALS AND METHODS: The sample consisted of 12 cases of oral leukoplakia and 60 cases of oral squamous cell carcinoma. FNAC and biopsy was done on all cases. A cytological and histopathological correlation was undertaken to determine the proportion of cancers that can be accurately diagnosed by FNAC and its ability to identify differentiation gradings of squamous cell carcinomas. A blind examination was undertaken. RESULTS: In oral leukoplakias equal rates of true positive and false negative results were obtained. The overall positive correlation accounted for 33.33% with 33.33% inadequate FNACs. In oral squamous cell carcinomas 92.85% of true positive and 7.14% of false negative results were obtained. The differentiation gradings correlated in only 41.07%. The overall positive correlation was 86.66% with 6.66% inadequate FNACs. CONCLUSIONS: The present study indicates that FNAC can be used as a reliable diagnostic test for oral squamous cell carcinoma but its use in oral leukoplakia is of limited value.

Health consequences of vasectomy in India.

Vasectomy acceptance has been declining in India during the past 20 years. Even if the risk of prostate cancer is marginally higher in vasectomized men, this risk in India has to be assessed against the immediate safety and other possible long-term benefits of this procedure. The Indian Council of Medical Research has launched a case-control study, which is unlikely to be time-consuming or beyond the available means and resources, in order to obtain definitive data on this problem. Meanwhile, vasectomy remains an excellent procedure for the couple seeking permanent methods of contraception, and specific efforts to promote its acceptance must continue in India.

PIP: The prevalence and acceptance of vasectomy in India has fallen from 74.2% (proportion of all sterilizations) in 1970 to 4.2% in 1992. Barriers in the organizational structure and poor access to services may contribute to the decrease in vasectomies. A review by the Indian Council of Medical Research (ICMR) has concluded that there is no consensus about an increased risk of prostate cancer among vasectomized men. The overall morbidity and mortality rates due to cancer in vasectomized men are equal to or lower than those of community-matched controls. Conflicting time-trends in the same study and differences between studies in the same country make it difficult to determine whether or not vasectomy decreases the risk of cardiovascular and cerebrovascular diseases. No studies have looked at an association between vasectomy and these diseases in India. WHO has asked the ICMR to participate in a multicountry study on prostate cancer. ICMR's Scientific Advisory Groups suggested that ICMR should also conduct a comprehensive case control study among men who are at least 50 years old who underwent vasectomy at least 10 years earlier. This ICMR-funded 2-year study, which has already begun, measures the risk of cardiovascular disease, cerebrovascular disease, and cancers other than prostate cancer. It will allow ICMR to weigh all the long-term risks and benefits of vasectomy in India against its short-term safety. The findings will provide potential clients information on the relative risk of prostate cancer and other diseases in vasectomized men in India, so they can make an informed choice. In the meantime, based on its immediate safety, low cost, and feasibility in a primary health care system, efforts to promote vasectomy acceptance in India must proceed, especially targeting couples wanting permanent contraception.