MutSα expression predicts a lower disease-free survival in malignant salivary gland tumors: an immunohistochemical study.

BACKGROUND: Appropriate DNA replication is vital to maintain cell integrity at the genomic level. Malfunction on DNA repair mechanisms can have implications related to tumor behavior. Our aim was to evaluate the expression of key complexes of the DNA mismatch-repair system MutSα (hMSH2-hMSH6) and MutSß (hMSH2-hMSH3) in a panel comprising the most common benign and malignant salivary gland tumors (SGT), and to determine their association with disease-free survival. MATERIAL AND METHODS: Ten cases of normal salivary gland (NSG) and 92 of SGT (54 benign and 38 malignant) were retrieved. Immunohistochemistry was performed for hMSH2, hMSH3, hMSH6. Scanned slides were digitally analyzed based on the percentage of positive cells with nuclear staining. Cases were further classified in MutSαhigh and MutSßhigh based on hMSH2-hMSH6 and hMSH3-hMSH6 expression, respectively. RESULTS: hMSH3 expression was lower in malignant SGT compared to NSG and benign cases. Adenoid cystic carcinoma (ACC) cases with perineural invasion presented a lower percentage of hMSH3 positive cells. hMSH6 was downregulated in both benign and malignant SGT compared to NSG. Malignant SGT cases with MutSαhigh expression had lower disease-free survival compared to MutSαlow cases. A 10.26-fold increased risk of presenting local recurrence was observed. CONCLUSIONS: Our findings suggest that a lack of hMSH3 protein function is associated with a more aggressive phenotype (malignancy and perineural invasion) and that MutSα overexpression predicts a poor clinical outcome in malignant SGT.

Comparison of the whole slide imaging and conventional light microscopy in the grading of oral epithelial dysplasia: a multi-institutional study.

BACKGROUND: Whole Slide Imaging (WSI) is an alternative method to light microscopy (LM). However, few studies have compared the diagnostic agreement between WSI and LM, especially to grade oral epithelial dysplasia (OED). The purpose of this study was to evaluate the variability in grading OED by the World Health Organization grading system, using WSI and conventional LM, and to investigate whether the access to clinical information, and psychologic or physical states of the pathologists could interfere with the diagnosis. MATERIAL AND METHODS: eleven experienced pathologists from seven Brazilian universities independently evaluated twenty-five OED cases. The analyses were performed in duplicate for each method, with an interval of at least 30 days, and the time consumed in each analysis was measured. Physical and psychologic states were evaluated by blood pressure levels, heart rate and two questionnaires: State-Trait Anxiety Inventory and Perceived Stress Scale. Clinical information was provided after the second evaluation using WSI and the pathologist could change their diagnostic decision or not. RESULTS: LM showed a higher inter-examiner agreement (k=0.53) than WSI (k=0.45) and a smaller time consumed by the pathologists (mean of 65.53 seconds compared to 91.02 seconds in WSI). In the first analysis using conventional microscopy, there was a positive correlation between kappa values and anxiety (r=0.47, p=0.02), and stress (r=0.64, p<0.01), and an inverse correlation with heart rate (r=-0.48, p=0.02). In the digital analysis, there was also a positive correlation between kappa values and anxiety (r=0.75, p<0.001). After clinical information was given, there was a slight change in 11.3% of the cases, and a great discrepancy in 1.1% of the cases, mainly increasing the OED grade. CONCLUSIONS: both microscopy systems had similar results, although LM had slightly higher kappa values, and WSI was more time consuming.

CD1a+ and CD207+ cells are reduced in oral submucous fibrosis and oral squamous cell carcinoma.

BACKGROUND: The objective of this study investigated the distribution of immature dendritic cells (DCs), Langerhans cells and plasmacytoid DCs in oral submucous fibrosis (OSMF), OSMF associated with oral squamous cell carcinoma (OSMF-OSCC), oral leukoplakia (OL), and oral squamous cell carcinoma (OSCC). MATERIAL AND METHODS: Fourteen cases of OSMF, 9 of OSMF-OSCC, 8 of OL¸ 45 of OSCC and 8 of normal epithelium were retrospectively retrieved and their diagnoses confirmed. Immunoreactions against CD1a, CD207 e CD303 were performed and the number of positive cells quantified. RESULTS: A significant decrease of CD1a+ was found in OSMF (p≤0.05), OSMF-OSCC (p ≤ 0.01), and OSCC (p ≤ 0.001) when compared to normal epithelium. For CD207+ the significance decrease was observed in OSMF-OSCC (p ≤ 0.05), and OSCC (p ≤ 0.01) when compared with normal epithelium, and in OSMF when compared with OL (p ≤ 0.05). There was no significant difference for CD303, but increased in CD303+ was observed in OSCC when compared with normal epithelium. CONCLUSION: The decrease in the number of CD1a+ and CD207+ cells may be associate to the development of oral OSCC, and in OPMDs they might be indicators of malignant transformation.

Radiographic estimation of the growth rate of initially underdiagnosed ameloblastomas.

BACKGROUND: To evaluate the specific growth rate (SGR) of ameloblastoma. MATERIAL AND METHODS: cases of ameloblastoma initially underdiagnosed (e.g. cases overlooked or diagnosed as reactive lesions) which had adequate radiographic documentation to evaluate their progression were retrospectively selected. Two panoramic radiographs were analyzed to determine the specific growth rate (SGR) of each tumor, defined as the logarithm of the ratio of final tumor area (when the diagnosis of ameloblastoma was made) to the initial tumor area (when the lesion was underdiagnosed), divided by the time interval between the radiographic images. The tumor area was measured using the software ImageJ. RESULTS: Twelve patients with mandibular ameloblastomas were selected, including 5 males and 7 females, with a mean age of 24.9 years (range: 14-61 years). In four cases, the lesion was associated with the crown of an impacted third molar. In three cases, it was initially diagnosed as a periapical lesion. Three cases were extrafollicular and were not noticed in the initial radiographs. Two cases were initially diagnosed as ameloblastoma, but the surgery was delayed for personal reasons. The mean interval of time between the two radiographic images was 4.3 years (range: 0.4-9 years). Based on our analysis, ameloblastoma grows in average 40.4% per year (range: 14.9-88.7%). CONCLUSIONS: Ameloblastoma is a progressively growing tumor, but its growth rate seems to be smaller than initially reported in the literature. Better understanding the radiographic progression of ameloblastoma might improve its early diagnosis, management, and prognosis.

Atividade antibacteriana de Óleos Essenciais sobre Streptococcus mutans e Staphylococcus aureus / Antibacterial Activity of Essential Oils against Strains of Streptococcus and Staphylococcus

Este trabalho objetivou avaliar a ação antimicrobiana in vitro dos óleos essenciais de Ocimum basilicum (Manjericão Exótico), Thymus vulgaris (Tomilho Branco), e de Cinnamomum cassia (Canela da China) sobre cepas bacterianas de Streptococcus mutans (ATCC 25175) e Staphylococcus aureus (ATCC 25923). A atividade antibacteriana dos óleos essenciais foi determinada pela Concentração Inibitória Mínima (CIM) e a Concentração Bactericida Mínima (CBM) através da técnica de microdiluição e do esgotamento. Para a CIM, foram utilizadas placas de 96 poços e inseriu-se 100µL de caldo BHI, 100µL da diluição dos óleos essenciais no primeiro poço e 10µL da suspensão bacteriana (1,5x10(6) microrganismos/mL). Realizou-se a diluição seriada partindo-se da concentração inicial de 8% até 0,0625%. A CIM correspondeu à última diluição na qual não foi verificada a presença de bactérias. Para obter a CBM, realizou-se a semeadura em Ágar Miller-Hinton das diluições correspondentes a CIM, 2CIM e 4CIM. As placas foram incubadas a 37º C em estufa bacteriológica por 24 horas. Os testes foram realizados em triplicata tendo a clorexidina como controle positivo. Para S. aureus (ATCC 25923) a CIM e CBM dos óleos essenciais de C. cassia, O. basilicum e T. vulgaris foram 0,0625%, 4% e 0,0625%, respectivamente. Para S. mutans a CIM e a CBM dos óleos essenciais de C. cassia e T. vulgaris foram 0,125% e 0,25%, respectivamente. Já a CIM do O. basilicum foi 4% e não apresentou ação bactericida. Conclui-se que os óleos essenciais avaliados apresentaram ação antibacteriana frente a cepas de S. mutans e S. aureus, sendo que os menores valores de CIM e de CBM foram provenientes dos óleos de C. cassia e T. vulgaris.

The aim of this study is to evaluate the in vitro antimicrobial activity of essential oils of Ocimum basilicum (basil), Thymus vulgaris (thyme) and Cinnamomum cassia (Chinese cinnamon) against strains of Streptococcus mutans (ATCC 25175) and Staphylococcus aureus (ATCC 25923). The antibacterial activity of the essential oils was determined by Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC). The MIC was obtained by the microdilution technique using 96-well microplates, in which we inserted: 100µL of Brain Heart Infusion broth at double concentration, 100µL of the dilution of the essential oils and 10µL of bacterial suspension (1.5 x 10(6) organisms / mL). The products were diluted from the initial concentration of 8% up to 0.0625%. The MIC corresponded to the last dilution in which there was no presence of bacteria or turbidity in the culture medium. The MBC was obtained by seeding, in Mueller-Hinton agar, 10µL aliquots of dilutions corresponding to the MIC and the two immediately preceding ones (2MIC and 4MIC). The plates were incubated at 37°C in a bacteriological incubator for 24 hours. The tests were performed in triplicate, and 2% Chlorhexidine Digluconate was the control product. For S. aureus, the MIC and MBC of the essential oils of C. cassia, O. basilicum and T. vulgaris were 0.0625%, 0.0625% and 4%, respectively. For S. mutans, the MIC and MBC of the essential oils of C. cassia and T. vulgaris were 0.125% and 0.25%, respectively. The MIC of O. basilicum against S. mutans was 4% and the essential oil showed no bactericidal action. Chlorhexidine Digluconate presented antibacterial activity against all organisms. The evaluated essential oils presented antibacterial activity against the strains of S. mutans and S. aureus, and we highlight the essential oils from C. cassia and T. vulgaris with the lowest MIC and MBC.