E-CADERIN, N-CADERIN, SLUG, SNAIL, and TWIST contribute to epithelial-mesenchymal transition in salivary gland tumors

BACKGROUND

Transcription factors are important in the epithelial-mesenchymal transition process and are possibly related to the development of a more invasive tumor phenotype. Thus, the objective of this study was to analyze the expression and identify the localization of cellular markers related to the epithelial-mesenchymal transition process in salivary gland tumors.

STUDY DESIGN

The expression and localization of E-CADERIN, N-CADERIN, SLUG, SNAIL, and TWIST were evaluated, using immunohistochemistry, in 48 salivary gland tumors, being 17 pleomorphic adenomas (PA), 14 adenoid cystic carcinomas (ACC), and 17 mucoepidermoid carcinomas (MEC). these proteins were compared to clinical and histopathologic parameters. normal gland tissues were included for immunohistochemical comparisons.

RESULTS

ACC and MEC cases showed higher expression of SNAIL compared to PA. MEC showed high expression of SLUG and TWIST. Low expression of N-CADHERIN, SNAIL, and TWIST in ACC was frequent in T3 and T4. High expression of TWIST in MEC was more frequent at age ≥ 40 years A positive correlation was only observed between N-cadherin/SNAIL in ACC, between SNAIL/TWIST in MEC, and between SLUG/TWIST in PA.

CONCLUSION

This study provided insight into EMT-related proteins (E-cadherin, N-cadherin, SNAIL, SLUG, and TWIST) and their contribution to the maintenance of morphogenesis and the development of the salivary gland tumors and showed a positive correlation among N-CADHERIN/SNAIL in ACC and SNAIL/TWIST in MEC.

Florid cemento-osseous dysplasia-related osteonecrosis: A series of cases

OBJECTIVE

The aim of this study was to assess the clinicopathological features of florid cemento-osseous dysplasia (FCOD)-related osteonecrosis highlighting their histopathological aspects and bone structure.

METHODS

Twenty-two FCOD-related osteonecrosis cases were evaluated retrospectively. Osteonecrosis, osteomyelitis, bacterial colonization, bone resorption, reactive bone, osteon-like structure, lamellar bone, and basophilic lines were analyzed. Specific staining and fluorescence and polarized light microscopy analyses were also performed.

RESULTS

The mandible was more affected by FCOD-related osteonecrosis. There was a predominance of African-Brazilian women in the fifth and seventh decades of life. Osteomyelitis was present in 82 % of cases whereas bone resorption and bacterial colonization were present in 100 % of FCOD-related osteonecrosis cases. Thick basophilic lines were seen in all cases (100 %). Actinomycosis and osteoclasts were not often.

CONCLUSIONS

This study showed female adult preference, mandibular location, and some findings such as osteomyelitis, bone resorption, and bacterial colonization were histopathological features more frequent in FCOD-related osteonecrosis. In the absence of a close clinical and radiographic correlation, the morphology of the necrotized bone similar to cementum could help to recognize FCOD.

Association between occupational exposure to domestic solid waste and dental caries: a cross-sectional study

Studies have shown that domestic waste collectors are exposed to toxicants including infectious pathogens, which may be linked to their oral health conditions. This cross-sectional study evaluated the dental caries and its associated factors among domestic waste collectors. A total of 301 adult men who worked for a waste collection corporation were included; 171 men worked in direct contact with domestic solid waste and 130 did not. Sociodemographic data, working, and medical history were assessed. The decayed, missing, and filled permanent teeth (DMFT) index was examined. Logistic regression analysis was used to identify factors associated with dental status with a significance level of 5%. The overall mean DMFT score was 8.36±5.64. The mean DMFT, missing teeth (MT), and filled teeth (FT) were significantly higher in workers who did not have any direct contact with waste (p≤0.04). In the logistic analysis, DMFT ≥8 was only associated with older age (OR=8.41 [95% confidence interval (95%CI), 5.01-14.12], p<0.001). Decayed teeth (DT) ≥2 was associated with no previous oral hygiene instruction (OR=2.70 [1.50-4.81], p=0.001) and no daily dental flossing (OR=4.26 [1.92-9.43], p<0.001). MT ≥9 was associated with lower education level (OR=3.33 [1.57-7.10], p= 0.002). FT≥3 had a negative association with low income (OR= 0.42 [0.25-0.70], p<0.001) and no daily flossing (OR=0.42 [0.23-0.76], p=0.004). In conclusion, occupational exposure to domestic solid waste was not associated with poor dental status. Instead, age, education, income level, and oral hygiene were associated with dental health status. Missing teeth constituted the major component of the DMFT index. Therefore, prevention and oral rehabilitation programs are necessary to improve dental health.

Central giant cell granuloma: A clinicopathological and immunohistochemical study of macrophages, blood vessels, lymphatic vessels and regulatory proteins

OBJECTIVE

This study seeks to investigate immunohistochemical parameters that could distinguish non-aggressive Central giant cell granuloma (CGCG) from aggressive CGCG, two groups of lesions which differ in their clinical and radiographic features and prognosis.

MATERIAL AND METHODS

12 cases of non-aggressive CGCG and 11 cases of aggressive CGCG were investigated and associated the immunohistochemical expression of macrophages (CD68 and CD163), blood vessels (CD34 and CD105), lymphatic vessels (D2-40) and regulator proteins (p63 and Ki-67). Clinical and radiographic features were also studied.

RESULTS

Associations between all proteins in non-aggressive and aggressive CGCG were not significant (p > 0.05). With respect to non-aggressive CGCG, there were no significant correlations, while in aggressive CGCG there was a significant positive correlation between CD68 and CD163 (p = 0.031), between CD34 and D2-40 proteins (p = 0.04), whereas a significant negative correlation was observed between CD105 and CD68 (p = 0.040). However, regardless of aggressiveness of CGCG, there was a significant positive correlation between CD68 and CD163 (p = 0,04). Among the clinical and immunohistochemical aspects, only the symptomatology was a significant risk factor for the occurrence of aggressive CGCG (OR = 12.00/p = 0.016).

CONCLUSION

Macrophages and angiogenesis contribute to their maintenance and development of CGCG. In addition, immunohistochemistry used here was not able to differentiate their aggressiveness. However, symptomatology was proved to be a risk factor for the occurrence of aggressive CGCG. It is possible that clinical features, particularly symptomatology, represent the most appropriate parameter to attempt to distinguish GCCG.

Ameloblastoma with adenoid features: A series of eight cases

BACKGROUND

Ameloblastoma with adenoid features are characterized by the presence of duct-like structures formed from the parenchyma of the tumor. This study was conducted to report a series of eight ameloblastomas with adenoid features, highlighting their clinicopathological and immunohistochemical aspects.

MATERIAL AND METHODS

Out of 71 cases of ameloblastomas, this study classified 8 cases as ameloblastomas with adenoid features. Clinicopathological data and immunohistochemistry for CK7, CK14, CK19, IMP3, p53 and Ki-67 were evaluated.

RESULTS

From those cases of ameloblastoma exhibiting adenoid features, there were 4 women and 4 men, with mean age of 39 years. Most cases affected the mandible and all presented radiographically as a radiolucency. The predominant histopathological features were pseudoducts, squamous metaplasia, nuclear hyperchromatism, clear cells, whorled aspect of epithelial structures, cribriform growth pattern, proliferation of spindle cells and extracellular eosinophilic material. Immunohistochemical analysis showed high expression for CK14 (n = 6) and CK19 (n = 3) and all cases (n = 8) were negative for p53, IMP3 and CK7. In addition, all samples (n = 8) showed low expression for Ki-67.

CONCLUSIONS

The similarities between the histopathological and immunohistochemical features of eight cases described in the present study and those described in previous studies support the possibility that these lesions are adenoid ameloblastomas. In addition, the immunohistochemical results of CK14, CK19, p53 and Ki-67 did not differ from those of conventional ameloblastomas.

Glypican-3 distinguishes aggressive from non-aggressive odontogenic tumors: a preliminary study

BACKGROUND

Glypican-3 is a cell surface proteoglycan that is found in embrionary tissues, and there are no studies investigating this protein in odontogenic tumor. Thus, the aim of this study was to investigate glypican-3 in a series of aggressive and non-aggressive odontogenic tumors.

METHODS

Fifty-nine cases of tumors were divided into aggressive odontogenic tumors (20 solid ameloblastomas, four unicystic ameloblastoma, 28 KOTs including five associated with Gorlin-Goltz syndrome) and non-aggressive odontogenic tumors (five adenomatoid odontogenic tumors and two calcifying cystic odontogenic tumors) and analyzed for glypican-3 using immunohistochemistry.

RESULTS

Glypican-3 was observed in seven solid ameloblastoma and eighteen keratocystic odontogenic tumors including three of the five syndromic cases, but there was no significant difference between syndromic and sporadic cases (P > 0.05; Fisher's exact Test). All cases of unicystic ameloblastoma (n = 4), adenomatoid odontogenic tumor (n = 5), and calcifying cystic odontogenic tumor (n = 2) were negative.

CONCLUSIONS

This provided insights into the presence of glypican-3 in odontogenic tumors. This protein distinguished aggressive from non-aggressive odontogenic tumors.

Interaction of stromal and microvascular components in keratocystic odontogenic tumors

OBJECTIVE

Little is known about the interaction of stromal components in odontogenic tumors. Thus, the aim of this study was to investigate mast cells (MCs), myofibroblasts, macrophages, and their possible association with angiogenesis and lymphangiogenesis in keratocystic odontogenic tumors (KCOTs).

MATERIAL AND METHODS

Thirty cases of KCOTs were included and analyzed by immunohistochemistry for mast cell tryptase, α-SMA, CD34, CD163, and D240. For comparative purpose, 15 radicular cysts (CRs) and 7 pericoronal follicles (PFs) were included.

RESULTS

There was an increase in MCs for RCs and this difference was significant when they were compared to KCOTS and PFs. A significant increase in the density of MFs was observed for KCOTs when compared to RCs and PFs (P = 0.00). No significant difference in CD163-positive macrophages (P = 0.084) and CD34-positive vessels (P = 0.244) densities was observed between KCOTs, RCs, and PFs, although KCOTs showed a higher density of all proteins. Significant difference in lymphatic vessel density was observed for KCOTs when compared to RCs and PFs (P = 0.00). Positive correlation was observed between mast cell tryptase and CD34 in KCOTs (P = 0.025).

CONCLUSIONS

A significant interaction between the MC population and CD34-positive vessels in KCOTs supported the hypothesis that MCs and blood vessels contribute to the stromal scaffold of KCOT.

Cytogenetic biomonitoring of oral mucosa cells of crack cocaine users

The aim of the present study was to comparatively evaluate genomic damage (micronucleus) and cellular death (pyknosis, karyolysis, and karyorrhexis) in exfoliated oral mucosa cells from crack cocaine users by micronucleus test. A total of 30 crack cocaine users and 30 health controls (non-exposed individuals) were included in this setting. Individuals had epithelial cells from cheek mechanically exfoliated, placed in fixative, and dropped in clean slides, which were checked for the above nuclear phenotypes. The results pointed out significant statistical differences (p < 0.05) of micronucleated oral mucosa cells from crack cocaine users. Exposure to crack cocaine caused an increase of other nuclear alterations closely related to cytotoxicity such as karyolysis in oral cells as well. In summary, these data indicate that crack cocaine is able to induce chromosomal breakage and cellular death in oral mucosa cells of users.

Oral mucoceles: a clinical, histopathological and immunohistochemical study

The aim of study was to evaluate the clinicopathological features of oral mucoceles and the immunohistochemical expression of cellular and extracellular matrix components in these lesions. One hundred cases of oral mucoceles were examined for clinicopathological features. The expression of mast cell tryptase, CD68, MMP-1 (matrix metalloproteinase-1), MMP-9 (matrix metalloproteinase-9) and CD34 was investigated immunohistochemically in 32 cases. The lesions arose as nodules or blisters of variable color. The mean age was 23.2 years and a higher male frequency was observed. The most common locations were the lower lip (92%), followed by the floor of the mouth (7%), and palate (1%). The lesion size ranged from 0.4 to 3.0cm. Unusual histopathological findings as superficial mucoceles (n=16, 16%), pseudopapillary projections (n=3, 3%), epithelioid histiocytes (n=4, 4%), multinucleated giant cells (n=1, 1%) and myxoglobulosis (n=9, 9%) were also seen. Mast cells and CD68-positive macrophages, MMP-1, MMP-9 and CD34-positive blood vessels were seen in all cases. A significant association was seen between mast cells and MMP-1 (p=0.03) and between macrophages and MMP-1 (p=0.01). This study provided important insight into the demographic and histopathological occurrence of oral mucoceles. The tissue remodeling seen in these lesions mainly involved the migration and interaction of mast cells, macrophages and MMP-1.

Keratocystic odontogenic tumour arising as a periapical lesion

AIM

To document a case of a keratocystic odontogenic tumour (KOT) involving the apical region in the maxilla mimicking a periapical lesion of endodontic origin.

SUMMARY

Benign and malignant tumours, including odontogenic lesions, can be erroneously diagnosed as periapical radiolucencies. KOTs mimicking periapical lesions of endodontic origin are uncommon, especially when the lesions involve the maxilla. This article describes a 55-year-old man with a well-delimited, oval-shaped, radiolucent lesion, occupying the middle and apical third of teeth 22 and 23. After 30 days, the clinical and radiographic findings remained unchanged and the patient was referred for surgical removal of the lesion. Clinical, radiographic and histopathological features are also discussed and compared with current literature.

Altered phenotype and function of dendritic cells in individuals with chronic periodontitis

OBJECTIVE

To investigate the effects of periodontal bacterial lysates on maturation and function of mature monocyte-derived dendritic cells (m-MDDCs) derived from individuals with chronic periodontitis (CP) or healthy periodontal tissue (HP).

DESIGN

m-MDDCs derived from peripheral blood monocytes, cultured for 7 days in presence of interleukin (IL)-4 and granulocyte-macrophage colony stimulating factor (GM-CSF), were stimulated with lysates of Streptococcus sanguinis, Prevotella intermedia, Porphyromonas gingivalis, or Treponema denticola on day 4, and were then phenotyped. IL-10, IL-12 and IFN-gamma concentration in the supernatant of cultures were measured.

RESULTS

Expression of HLA-DR was lower in bacterial-unstimulated mature m-MDDC from CP compared to HP (p=0.04), while expression of CD1a and CD123 were higher in CP. The expression pattern of HLA-DR, CD11c, CD123, and CD1a did not change on bacterial stimulation, regardless of the bacteria. Stimulation with P. intermedia upregulated CD80 and CD86 in CP cells (p≤0.05). Production of IL-12p70 by bacterial-unstimulated m-MDDCs was 5.8-fold greater in CP compared to HP. Bacterial stimulation further increased IL-12p70 production while decreasing IL-10. Significantly more IFN-gamma was produced in co-cultures of CP m-MDDCs than with HP m-MDDCs when cells were stimulated with P. intermedia (p=0.009).

CONCLUSIONS

Bacterial-unstimulated m-MDDC from CP exhibited a more immature phenotype but a cytokine profile biased towards proinflammatory response; this pattern was maintained/exacerbated after bacterial stimulation. P. intermedia upregulated co-stimulatory molecules and IFN-gamma expression in CP m-MDDC. These events might contribute to periodontitis pathogenesis.

CD1a-positive Langerhans cells and their relationship with E-cadherin in ameloblastomas and keratocystic odontogenic tumors

BACKGROUND

Ameloblastomas and keratocystic odontogenic tumors (KOTs) are lesions that are characterized by locally invasive growth and cause extensive bone destruction. In addition, it is known that E-cadherin influences the adhesion of Langerhans cells (LCs) to keratinocytes.

OBJECTIVE AND METHODS

The aim of this study was to investigate, using immunohistochemistry, the distribution of CD1a-positive cells in ameloblastomas and KOTs and their relationship with E-cadherin, in comparison to calcifying cystic odontogenic tumor (CCOT).

RESULTS

The CD1a-positive LCs were observed in 11 ameloblastomas and KOTs. All of the cases of CCOT showed CD1a-positive LCs and a significant difference was found when this tumor was compared with ameloblastomas (P < 0.05, Mann-Whitney test). A statistically significant difference was also noted when comparing CD1a-positive LCs between CCOTs and KOTs (P < 0.05, Mann-Whitney test). Lower expression of E-cadherin in ameloblastomas (AMs) in relation to KOTs and CCOTs (P < 0.05, Fisher test) was observed. There was no correlation between E-cadherin and CD1a-positive LCs between all odontogenic tumors that were studied (P > 0.05, Spearman test).

CONCLUSION

A quantitative difference of CD1a-positive cells between AMs and KOTs in comparison to CCOTs was observed. This permits to speculate that a depletion of CD1a-positive LCs might influence the local invasiveness of ameloblastomas and KOTs. Furthermore, it is suggested that E-cadherin mediates cell adhesion in these tumors.

[Characteristics of the access and utilization of public dental services in medium-sized cities]

This cross-sectional study sought to describe the main characteristics of access and utilization of primary and specialized public dental services in two medium-sized cities in Bahia with 100% coverage of the Family Health Program. A survey of 952 households and 2.539 individuals aged over 15 years was conducted. The main variables analyzed were: perceived oral health needs, demand for the service, barriers of organizational access and the type of service and procedure utilized. The use of specialized public dental services was of 11.7% and primary care was 26%. In the city where there was greater use of public dental services, there was less use of private services. The main barrier to access remained in primary care (from 5.0% to 15.2%). There was little interface between secondary care a primary care, as only 16.6% of users returned to this level of care. In conclusion, the main barrier to access in cities with specific organizational and geographic realities appears to be in primary dental care. Individual preventive actions were little reported. It is recommended that barriers to access in primary care be eliminated, and also that a protocol (clinical guides) be established to foster the continuity and longitudinality of primary dental care.

Laser GaAlAs (λ860 nm) photobiomodulation for the treatment of bisphosphonate-induced osteonecrosis of the jaw

OBJECTIVE

The aim of this article is to report a case of bisphosphonate-induced osteonecrosis (ONJ-BP) of the jaw treated by curettage of the necrotic bone, low-level laser therapy (LLLT), and antibiotic therapy.

BACKGROUND DATA

ONJ-BP is characterized by painful ulcerations of the oral mucosa, is prone to bone necrosis that does not heal within 8 weeks after diagnosis, and is often difficult to treat. No definitive standard of care has been established for ONJ-BP. LLLT improves wound healing, relieves pain, and appears to be a promising treatment modality for patients with ONJ-BP.

MATERIALS AND METHODS

An 82-year-old man taking intravenous bisphosphonate presented with ONJ-BP after tooth extraction. The patient was treated by LLLT using a GaAlAs diode laser with the following settings: wavelength, 860 nm; 70 mW; continuous wave; and spot size 4 mm(2). An energy density of 4.2 J/cm(2) per point was applied in a punctual contact manner every 48 h for 10 days, in association with antibiotic therapy and curettage of the necrotic bone. Reduction in painful symptoms was reported after the second irradiation session, and tissue healing was complete at the end of the third week following oral curettage. The patient was followed up for 12 months and exhibited good oral healt and quality of life.

CONCLUSIONS

The therapeutic protocol used in this study had a positive effect on tissue healing and remission of painful symptoms, resulting in better oral health and quality of life for the patient.

Distribution of mast cells in benign odontogenic tumors

The aim of this study was to investigate the presence of mast cells in a series of odontogenic tumors. Forty-five cases of odontogenic tumors were investigated using immunohistochemistry for mast cell triptase, and differences between groups were statistically evaluated. Mast cells were present in 96% of odontogenic tumors. Mast cells present in solid ameloblastoma were observed in the tumor stroma surrounding more solid and follicular epithelial islands, with or without squamous metaplasia. The odontogenic mixoma showed few mast cells. In odontogenic tumors with a cystic structure, the mast cells were distributed throughout all areas of the lesions, mainly in keratocystic odontogenic tumor. In addition, the total density of mast cells between all odontogenic tumors showed no significant difference (p > 0.05). A greater mast cells distribution was found in keratocystic odontogenic tumor in relation to adenomatoid odontogenic tumor (p < 0.01), and when the unicystic ameloblastoma and keratocistic odontogenic tumor were compared to the odontogenic myxoma (p < 0.05). Syndrome keratocystic odontogenic tumor showed a higher mean of mast cells when compared with the other tumors of the sample. Mast cells values presented by syndrome keratocystic odontogenic tumor were significantly greater than those of the sporadic keratocystic odontogenic tumor that were not associated with the syndrome (p = 0.03). Mast cells are probably one of the major components of the stromal scaffold in odontogenic tumors. We found significant differences of mast cells between syndrome nonsyndrome keratocystic odontogenic tumors, although their distribution did not seem to have any influence on the biologic behavior of benign odontogenic tumors.

Actinic cheilitis among agricultural workers in Campinas, Brazil

OBJECTIVE

To assess the prevalence of Actinic Cheilitis (AC) among agricultural workers and analyze its risk factors.

DESIGN

A cross sectional epidemiological study. A lip lesion was defined as an abnormal change on the lip mucosa surface, such as erythematous pigmented, ulcerative or swelling (Cataldo and Doku, 1981). Data were gathered according to age group, gender, ethnicity-time and frequency of occupational sunlight exposure, smoking habits, drinking habits and socio-economic status.

SETTING

Sugar-cane plantation farms in Brazil.

PARTICIPANTS

Full-time workers of both genders employed at sugar-cane plantation farms for at least six months.

OUTCOME MEASURES

Correlations between AC prevalence, demographic and socioeconomic risk factors.

RESULTS

202 people were examined and the prevalence of AC was 39.6%. Results revealed that being black (0.15-0.88- 95% CI; OR = 0.36; p = 0.025) or mulatto (0.21-0.82- 95% CI; OR = 0.42; p =0.011) decreased the risk for AC, while age and gender sex had no effect. In relation to socioeconomic variables, formal education and more than four years of education (0.07-0.68- 95% CI; OR = 0.22; p = 0.009) decreased the risk for AC. Moreover, drinking alcohol was a risk for AC (1.05-3.37- 95% CI; OR = 1.88; p = 0.034), while tobacco smoking was not (0.60-2.02- 95% CI; OR = 1.10; p = 0.763).

CONCLUSIONS

The prevalence of AC is high in agricultural workers who were fairskinned, had low education and high alcohol intake. Prevention and early diagnosis are required for workers exposed to sunlight.

Efficacy of nimesulide versus meloxicam in the control of pain, swelling and trismus following extraction of impacted lower third molar

This study compared the efficacy of nimesulide and meloxicam in the control of pain, swelling and trismus, following the extraction of impacted inferior third molars. Twenty patients with two impacted inferior third molars, in similar positions, were selected. The patients were designated randomly to the meloxicam group (MEL: 7.5mg twice a day for 5 days) or the nimesulide group (NIM: 100mg for 5 days). Following the extractions, swelling was more pronounced in the MEL group than in the NIM group (P<or=0.001). There were no significant differences in pain intensity between the treatment groups (P>0.05). At the 72-h evaluation, reduction was significantly larger in mouth opening in the MEL group compared with the NIM group (P<0.05). In conclusion, pain control was similar in both treatment groups. NIM was more effective than MEL in the control of swelling and trismus following the extraction of impacted lower third molars.

The impact of a 17-day training period for an international championship on mucosal immune parameters in top-level basketball players and staff members

This investigation examined the impact of a 17-d training period (that included basketball-specific training, sprints, intermittent running exercises, and weight training, prior to an international championship competition) on salivary immunoglobulin A (SIgA) levels in 10 subjects (athletes and staff members) from a national basketball team, as a biomarker for mucosal immune defence. Unstimulated saliva samples were collected at rest at the beginning of the preparation for the Pan American Games and 1 d before the first game. The recovery interval from the last bout of exercise was 4 h. The SIgA level was measured using enzyme-linked immunosorbent assay and expressed as absolute concentrations, secretion rate, and SIgA level relative to total protein. The decrease in SIgA levels following training was greater in athletes than in support staff; however, no significant differences between the two groups were detected. A decrease in SIgA level, regardless of the method used to express IgA results, was verified for athletes. Only one episode of upper respiratory tract illness symptoms was reported, and it was not associated with changes in SIgA levels. In summary, a situation of combined stress for an important championship was found to decrease the level of SIgA-mediated immune protection at the mucosal surface in team members, with greater changes observed in the athletes.

Application of Two Different Clones of Vimentin to the Diagnosis of Salivary Gland Tumors

With the evolution of IHC techniques, a broad range of antibodies have become available to diagnostic immunohistology. The authors observed different expressions of vimentin in salivary gland tumors using two clones of this antibody. This study was undertaken to show these differences comparing the immunoexpression of two clones of vimentin (V9 and Vim 3B4, DAKO, Carpenteria, CA) using 10 pleomorphic adenomas, 10 adenoid cystic carcinomas, and 4 epithelial/myoepithelial carcinomas of the salivary glands. The V9 clone of vimentin was much more efficient in demonstrating the myoepithelial cells in the different tumors studied. The Vim 3B4 clone was capable of detecting some myoepithelial cells, the plasmacytoid or modified myoepithelial cells in the pleomorphic adenoma, but was very weak in epithelial/-myoepithelial carcinomas. The difference between the two clones studied is a warning that pathologists need to know the specificity and sensitivity of the reagent they are using.

Immunoexpression of extracellular matrix proteins in human salivary gland development

Immunoexpression of the extracellular matrix (ECM) proteins laminin, fibronectin, tenascin and types I, III and IV collagen was analyzed in the major and minor salivary glands of seven human fetuses at different gestational ages. The results showed the presence and localization of laminin, collagen IV and fibronectin around glandular structures at all stages of development. Tenascin was only detectable around excretory ducts. In the earliest stages of development, type I and type III collagen were presented as fine fibers delineating the glandular structures and delimiting the extension of the future lobule. As glandular development proceeded, the lobule was gradually filled with collagens and glandular tissue.

Long-term results of guided tissue regeneration therapy in the treatment of class II furcation defects: a randomized clinical trial

BACKGROUND

The purpose of this study was to evaluate the results after guided tissue regeneration (GTR) using a bioabsorbable membrane in Class II furcation defects in mandibular molars over a 24-month period.

METHODS

Nine patients with 2 comparable Class II furcation defects were included. The defects in each patient were randomly assigned to either test (GTR) or control (open flap debridement) group. Clinical measurements and standardized radiographs were taken at baseline, and at 6, 12, 18, and 24 months. The radiographs were analyzed by subtraction radiography.

RESULTS

There were significant probing depth reductions for both test and control groups (P < 0.007, P < 0.0005, respectively); however the differences between groups were not significant at any examination. The intra-group and inter-group differences in the vertical clinical attachment level gain were not significant (P > 0.05). Over 24 months, a significant horizontal clinical attachment level gain was observed in the test group compared to control (P<0.03). In the test group, 2 sites showed complete closure, one was converted to Class I, and one tooth was lost due to root resorption. In the control group, 2 defects progressed to Class III over 24 months. At 6 months, the test group showed 0.14 mm of bone loss while the control group showed 0.86 mm of bone gain (P = 0.035). The inter-group differences were not significant at 12, 18, and 24 months. A significant bone height gain was observed in the test group at 24 months when compared to the values obtained after 6 months (P = 0.015).

CONCLUSION

GTR may provide a greater horizontal clinical attachment level gain with the possibility of complete closure of some defects and stability over time.

Clinical, cytogenetic and toxicological studies in rural workers exposed to pesticides in Botucatu, São Paulo, Brazil

Pesticides can cause gene mutations and chromosomal aberrations in exposed individuals. We have investigated 24 workers exposed to pesticides. Clinical examinations and cytogenetic and toxicological tests were performed. Ten non-exposed individuals were used as controls. Toxicological dosages of copper, zinc and manganese (metals found in some pesticides), hepatic enzyme dosage (GOT, GPT, AR) and acetylcholinesterase activity were performed in 16 workers and 8 controls. In the exposed workers, the most relevant clinical symptoms were poor digestion with fullness sensation after meals, irritated eyes, headache and fasciculations. The exposed group showed significantly lower manganese dosage and acetylcholinesterase activity, and significantly higher levels of alkaline phosphatase. Cytogenetic studies showed significantly higher chromosomal aberrations in the exposed group compared to the control group. Although the workers used protection against the pesticide's fog, the results revealed that the workers were contaminated with the pesticides. Therefore, the cytogenetic, toxicological studies with clinical examination are necessary for monitoring workers who are exposed to pesticides in any situation.

Techniques in electromanometry of the upper esophageal sphincter

The various pull-through techniques used to measure pressure and length of the upper esophageal sphincter have not been studied in depth. Because of the importance of obtaining further information about these techniques, a group of 25 dogs was submitted to upper esophageal sphincter pressure and length measurements by three different pull-through techniques (two of the continuous type and one of the station type), each with three replications per animal, to determine possible differences among techniques. A single introduction provided reliable results, with no sequential effect of the measurements or of any one technique on resting pressure. However, each technique yielded different sphincter lengths, higher values being obtained when the continuous techniques were used.

Paracoccidioidomycosis in the region of Botucatu (state of São Paulo, Brazil). Evaluation of serum thyroxine (T4) and triiodothyronine (T3) levels and of the response to thyrotropin releasing hormone (TRH)

T4, T3 and TSH serum levels were measured in 25 patients with paracoccidioidomycosis. Thyroid T3 reserves were measured on the basis of the increase in T3 (delta T3) 2 h after intravenous injection of 200 micrograms TRH, and pituitary TSH reserves were measured on the basis of TSH increase (delta TSH) 20 min after the same injection. Twenty healthy volunteers with no history of thyroid disease were used as controls. When the two groups were compared, the following results were obtained: (a) there was no significant difference in mean T4, T3, delta TSH between groups; (b) reduced T3 levels were detected more frequently in patients with paracoccidioidomycosis, especially among those with the acute form of the disease or with the severely disseminated chronic form. The results suggest the occurrence of a reduction in peripheral conversion of T4 to T3, but do not indicate the occurrence of hypothyroidism in any of its forms (thyroid, pituitary or hypothalamic).