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Polymorphous adenocarcinoma (PAC) is a malignant neoplasm of the salivary gland with a low incidence worldwide, characterized by diverse morphological features. This study aimed to present a large and well-documented case series from a single Brazilian center. We analyzed demographic data, clinical presentations, histopathological features, and immunohistochemical characteristics of 26 cases of PAC. Most patients were women (n = 21), with a mean age of 58 years (range = 36 to 84 years). The typical clinical presentation was a fibrous/fibroelastic and firm nodular lesion, with an average diameter of 2 cm, most found on the palate (n = 15). The alveolar ridge, buccal mucous, and superior lip were also affected. Histologically, various patterns were observed, including tubular, solid, cribriform, papillary, and cystic. Glomeruloid slit-like structures (n = 11), clear cells (n = 13), and mucous cells (n = 8) were also identified. Surface papillary epithelial hyperplasia was observed in four cases, and the presence of myxoid and collagenous areas in the stroma in nine. Fusiform areas were noted in 2 cases and areas of squamous differentiation in one. A clear cell predominance was observed in 2 cases. Neural invasion was present in eight cases. All cases were positive for S-100 and Cytokeratin 7 (CK7), and negative for p-40. The Ki-67 index was low, with a mean of 2.5%. In this case series, PAC primarily affected minor salivary glands and exhibited some uncommon microscopic features. Oral pathologists should be aware of these findings to prevent misdiagnosis. [ABSTRACT FROM AUTHOR]

Leishmaniasis is a parasitic infection transmitted by the bite of infected female sandflies. It principally affects the skin, and the frequency of mucosal involvement is about 5% to 20%. Considering the rarity of leishmaniasis affecting the upper aerodigestive tract mucosa, we evaluated the characteristics of mucocutaneous leishmaniasis and mucosal leishmaniasis and the diagnostic difficulty when the parasites are scarce in tissue samples. The clinical, histopathological, histochemical, immunohistochemical, and molecular features of 17 cases of mucocutaneous leishmaniasis and mucosal leishmaniasis were assessed. Mucosal disease was principally found in the soft palate, oropharynx, and nose, manifesting mainly as a solitary ulcer. In hematoxylin and eosin-stained sections, 10 cases revealed abundant amastigotes within the macrophages. Giemsa staining was not shown to be helpful to confirm the diagnosis in 6 cases with scarce or nondetectable amastigotes. Immunohistochemistry (IHC) showed high sensitivity by positive staining in 14 out of 17 cases (82.3%). Polymerase chain reaction was shown to be more sensitive than IHC with 13 out of 14 (92.8%) positive cases, including the 3 IHC negative cases; however, this technique is not available in many endemic regions. In summary, we suggest that the IHC is a simple technique with rapid results and relatively low cost, when compared with other laboratorial procedures; thus, IHC is a helpful tool that should be implemented in the routine diagnosis of leishmania.

Oral squamous cell carcinoma (OSCC) invasion is followed by several stromal events such as inflammatory and immune cell infiltration, neo-vascularization, fibroblast activation and occasionally myofibroblast emergence. Our previous studies demonstrated that myofibroblasts in the stroma of OSCC are associated with a more aggressive behavior, leading to shorter patient overall survival. Therefore, we evaluated whether OSCC-associated myofibroblasts have different characteristics compared to OSCC-associated fibroblasts. OSCC myofibroblast cell lines were isolated, cultured and characterized on the basis of the expression of specific isoform α of smooth muscle actin (α-SMA) and of the excessive production of type I collagen. To assess the proliferative potential of the cell lines, growth curves were constructed, whereas the production and activity of matrix metalloproteinases (MMP) were analyzed by ELISA and enzymography, respectively. Myofibroblast clones were positive for α-SMA and vimentin, and negative for pan-cytokeratin and CD34. In long time cultures, western blotting, flow cytometry and ELISA analysis revealed constant α-SMA expression and elevated production of type I collagen. There were no differences on proliferative potential between fibroblast and myofibroblast clones, but myofibroblast cells secreted significantly higher levels of MMP-1, -2, -9 and -13. Furthermore, MMP-2 gelatinolytic activity was significantly higher in myofibroblast clones. The results of this study suggest that myofibroblasts may contribute to OSCC invasion through elevation of MMP synthesis.

Background: Polymorphisms in genes that are involved in folic acid metabolism may be important maternal risk factors for the birth of a child with nonsyndromic cleft lip and/or palate (NSCL/P). The aim of this study was to determine the involvement of polymorphic variants in four genes (MTHFR, MTHFD1, MTR, and SLC19A1) that encode proteins related to folic acid metabolism in the women with susceptibility for having a child with NSCL/P., Methods: DNA samples from 106 mothers of children with NSCL/P (case group) and from 184 mothers of healthy children (control group) were genotyped by polymerase chain reaction associated with restriction fragment length polymorphism (PCR-RFLP)., Results: One of 29 polymorphisms was associated with significantly increased maternal risk for NSCL/P. Mothers exhibiting the A variant allele (GA genotype) of the MTHFR rs2274976 polymorphism demonstrated a ~6 times increased risk for having a child with NSCL/P compared to G allele carriers (OR, 5.76; 95% CI, 3.32-9.99, p = 0.000001). Among mothers who did not use vitamins, the OR of NSCL/P was increased to 8.34 (95% CI, 3.75-18.55, p = 0.000001) in the presence of the GA genotype of the MTHFR rs2274976 polymorphism compared to those with the GG genotype. Gene-gene interaction analysis showed that the combination of MTHFR rs2274976, MTHFD1 rs2236225, and SLC19A1 rs1051266 was the best model for prediction of maternal risk for NSCL/P., Conclusion: The findings of the present study suggested that genetic variants of folic acid metabolic genes may modulate maternal susceptibility for having an offspring with NSCL/P., (Copyright © 2010 Wiley-Liss, Inc.)