Morphology of collagen fibers and elastic system fibers in actinic cheilitis.

Background: Actinic cheilitis (AC) is a premalignant condition intimately related to exposure of the lips to sun rays. Aim: The objective of this study was to evaluate the elastic and collagen fibers in the lamina propria of AC. The degree of epithelial atypia was correlated with the quantity of elastic and collagen fibers. Materials and Methods: Fifty-one cases were investigated. One slide was stained with hematoxylin-eosin for the evaluation of atypia, the second was stained with Weigert's resorcin-fuchsin for the assessment of elastic fibers, and the third slide was stained with Mallory's trichrome for the analysis of collagen fibers. Results: Ordinal logistic regression analysis revealed a significant correlation between the presence of atypia and collagen fibers (P<0.05). Conclusions: It was concluded that there seems to be a reduction in the quantity of collagen fibers in cases of moderate and severe atypia. No correlation was observed between the degradation of elastic system fibers and the grade of dysplasia.

Pathosis associated with radiographically normal follicular tissues in third molar impactions: a clinicopathological study.

BACKGROUND: The follicular tissue around impacted third molars has a potential to develop pathosis. However, it is generally assumed that the absence of abnormal radiolucency indicates the presence of a normal follicle. AIMS: The aim of this study was to investigate abnormalities associated with radiographically normal follicular tissue of third molar impactions. MATERIALS AND METHODS: One hundred eighty-five impacted third molars from 170 patients with no signs of abnormal radiolucency (follicular space < 3 mm) were used for this study. Follicular tissues of the relevant teeth were collected. Specimens were fixed in 10% formalin and stained routinely with hematoxilin and eosin to be independently examined by two pathologists. A diagnosis was registered only when the results from both pathologists were in concordance. Clinical details for each patient were registered in WHO standard forms to undergo chi-square statistical analysis. RESULTS: Fifty-three per cent of the specimens had developed pathosis. The incidence of pathosis was higher in the age group of 20-30 years, in men compared to women and in the mandible compared to the maxilla. CONCLUSION: The findings of this study suggest that radiographic appearance may not be reliable in the diagnosis of pathosis in follicular tissue as a surprisingly high rate of pathosis was found in the absence of any radiographically detectable sign.

Comparison of staining of mitotic figures by haematoxylin and eosin-and crystal violet stains, in oral epithelial dysplasia and squamous cell carcinoma.

Mitosis of cells gives rise to tissue integrity. Defects during mitosis bring about abnormalities. Excessive proliferation of cells due to increased mitosis is one such outcome, which is the hallmark in precancer and cancer. The localization of proliferating cells or their precursors may not be obvious and easy. Establishing an easy way to distinguish these mitotic cells will help in grading and understanding their biological potential. Although immunohistochemistry is an advanced method in use, the cost and time factor makes it less feasible for many laboratories. Selective histochemical stains like toluidine blue, giemsa and crystal violet have been used in tissues including the developing brain, neural tissue and skin. AIM OF THE STUDY: 1) To compare the staining of mitotic cells in haematoxylin and eosin with that in crystal violet. 2) To compare the number of mitotic figures present in normal oral mucosa, epithelial dysplasia and oral squamous cell carcinoma in crystal violet-stained sections with that in H and E-stained sections. MATERIALS AND METHODS: Ten tissues of normal oral mucosa and 15 tissues each of oral epithelial dysplasia seen in tobacco-associated leukoplakia and squamous cell carcinoma were studied to evaluate the selectivity of 1% crystal violet for mitotic figures. The staining was compared with standard H and E staining. Statistical analysis was done using Mann-Whitney U test. RESULTS: A statistically significant increase in the mean mitotic count was observed in crystal violet-stained sections of epithelial dysplasia as compared to the H and E-stained sections (p=0.0327). A similar increase in the mitotic counts was noted in crystal violet-stained sections of oral squamous cell carcinoma as compared to the H and E-stained sections.(p=0.0443). No significant difference was found in the mitotic counts determined in dysplasia or carcinoma by either the crystal violet (p=0.4429) or the H and E-staining techniques (p=0.2717). CONCLUSION: One per cent crystal violet provides a definite advantage over the H and E-stained sections in selectively staining the mitotic figures.

Significantly increased recovery of intestinal parasites on routine stool specimen evaluation.

Three hundred thirty-six stool samples from October 2001 through October 2002 were analyzed for the presence of intestinal parasites. Fifty-six of these (16.7%) were positive for a total of 66 parasites; 65/66 (98.5%) were detected by iodine and dimethyl sulfoxide-modified acid-fast (DMSO-mAFB) stained smears of fresh and formalin-ethylacetate sedimentation concentrated samples. Saline, iodine, and DMSO-mAFB stained smears of fresh stool samples alone detected significantly fewer parasites, finding only 50/66 (75.8%) (p < 0.05). Stool samples analyzed by trichrome stained specimens preserved in Zinc sulfate polyvinyl alcohol (Zinc PVA) detected only 41/ 66 (62.2%) of the parasites. In our study population, it was necessary to perform the National Committee for Clinical Laboratory Standard (NCCLS) recommended to accurately detect intestinal parasites. The concentration technique is simple and significantly increased the detection of intestinal parasites.

Determination of the morphological irregularities in the middle and apical 1/3rd region of the root canal system of permanent maxillary incisors.

A thorough knowledge of the root canal anatomy and an understanding of its variations from the normal are mandatory for the successful root canal therapy. The assessment and exploration of the accessory canal and apical delta is necessary to combat the persistent infection at the periapical area. The purpose of this study is to determine the morphological irregularities in the middle and apical 1/3rd region of the root canal system of maxillary incisors. A total of 100 maxillary incisors were decalcified, processed, sectioned at the middle and apical 1/3rd region and observed under an ordinary microscope. The frequency of accessory canals, apical delta and type of canal configuration were studied. Accessory canals were found in 5% of the teeth. There was absence of apical delta in all the specimens. Total specimens showed single canal extended from the pulp chamber to the apex (Type 1 canal configuration).

Reduction of experimental myocardial infarct size by pre-treatment with magnesium sulfate in rats.

Experimental myocardial infarction was induced in albino rats by administration of isoprenaline hydrochloride, 85 mg/kg, sc, daily for two consecutive days. Such rats were pretreated with either saline or magnesium sulfate (60 mg/kg) po, daily for three weeks, to serve as control or treated groups respectively. Heart specimens were taken for gross and histological examination at 24 hr, on 5th day, 12th day and 21st day. Infarct size was significantly reduced in the magnesium-treated group (P less than 0.05). We conclude that magnesium sulfate exerted a potent prophylactic effect in limiting infarct size in rats.

Effect of temperature of thawing and diluent on the post--thaw physiological changes of buffalo frozen semen.

The effect of thawing was studied in buffalo semen diluted in three diluents (Tris egg-yolk, Egg-yolk citrate and Citric Acid whey) at three temperatures (5 degrees C, 35 degrees C and 75 degrees C) on motility, eosin staining, morphological and acrosomal changes, hyaluronidase, glutamic oxalacetic transaminase and glutamic pyruvic transaminase activities. The motility and lack of staining of sperm by eosin were maximum on thawing at 35 degrees C and in tris egg-yolk diluent followed by egg-yolk citrate and citric acid whey. Hyaluronidase, glutamic oxalacetic transaminase and glutamic pyruvic transaminase increased significantly in the extra-cellular fluid on thawing of semen diluted with all the three diluents. The buffalo semen diluted in tris egg-yolk and thawed at 35 degrees C for 30 seconds gave the best results.