What is the frequency of floor of the mouth lesions? A descritive study of 4,016 cases.

BACKGROUND: The aim of this study was to investigate the frequency of oral lesions in the floor of the mouth from representative oral pathology centres in Latin America. MATERIAL AND METHODS: This study was conducted on biopsies obtained from January of 1978 to December of 2018 at nine Latin America oral and maxillofacial pathology centres. Gender, age and histopathological diagnosis were evaluated. Data were analysed using descriptive methods. Chi-square test was used for pairwise comparisons. RESULTS: From 114,893 samples, 4,016 lesions (3.49%) occurred in the floor of the mouth. Brazil showed 3,777 cases (94%), Mexico 182 cases (4.5%) and Argentina 57 cases (1.4%). Benign lesions represented 65.1% (2,617 cases), followed by 34.9% (1,404 cases) of malignant disorders. Lesions of epithelial origin were more frequent (1,964 cases; 48.9%), followed by salivary glands (1,245 cases; 31%) and soft tissue lesions (475 cases; 11.7%). The most common histological subtypes were oral squamous cell carcinoma (1,347 cases; 33.5%), ranula (724 cases; 18%), oral leukoplakia (476 cases; 11.8%) and inflammatory fibrous hyperplasia (239 cases; 5.9%). The lesion affected males in 2,129 cases and females in 1,897 cases. CONCLUSIONS: In the current study, lesions in the floor of the mouth represented 3.49% of biopsies submitted to oral pathology services and oral squamous cell carcinoma, ranula and leukoplakia were the most common lesions.

The impact of sample storage on molecular-based detection of Mycoplasma genitalium.

AIMS: Mycoplasma genitalium causes a common, sexually transmitted bacterial infection. This study assessed the detection of M. genitalium in stored urine samples to understand the impact of sample storage on M. genitalium detection. METHODS: Aliquots of M. genitalium-positive urine (n = 20 patients) were stored at either room temperature (22°C) or 4°C, without a preservative. At weekly intervals, samples were tested using the commercial test ResistancePlus MG® (SpeeDx® , Australia). We report the analysis at 1 week, an acceptable collection-to-test turnaround time, with further analysis over 5 weeks to illustrate degradation trends. RESULTS: After storing at 4°C, the proportion of specimens that remained positive for M. genitalium was 100% after 1 week and 95% after 4 weeks. Storage at 22°C led to more rapid decline in detection in the first 4 weeks, with 95% detected after 1 week and 85% at 2 weeks onwards. At 5 weeks, samples stored at both temperatures had an 85% M. genitalium detection rate, with increase in crossing points (Cq) of 0·72 (95% confidence interval (CI) 0·01-1·43; P-trend = 0·027) at 4°C, and 1·75 ((95% CI 0·79-2·71), P-trend <0·001) at 22°C. CONCLUSIONS: Urine samples stored without preservative, and unfrozen, retained high M. genitalium detection levels over the short term (up to 5 weeks). To minimize degradation, storing at 4°C is recommended. SIGNIFICANCE AND IMPACT OF THE STUDY: There is little known about the stability of clinical samples for M. genitalium detection. This study found that a high proportion (85-100%) of samples are still suitable for M. genitalium detection after storage for up to 5 weeks.

[Geometrical growth models of the fetal forebrain, cerebellum, brainstem and change of the cranial base angles during fetal period]. / Modèles géométriques de croissance du cerveau, cervelet, tronc cérébral et modification des angles de la base du crâne au cours de la période fœtale.

INTRODUCTION: Brain growth plays likely an important role for the skull growth. In the fetus, there exists an heterochrony for the growth of supratentorial (forebrain) and infratentorial regions (brainstem and cerebellum). The aim of the study was thus to model geometrically the growth of these two regions and to compare it with the inflection of the base of skull. MATERIAL AND METHODS: Brain growth measurements were performed from midsagittal photographs of fetal brains obtained from an Anatomical Atlas over a period from 10 to 40 amenorrhea weeks (AW). After countouring and pointing anatomical and geometrical landmarks, we have developed a linear growth model based on principal component analysis (PCA). Besides, the variation of the sphenoidal and clivo-foraminal angles was studied from anatomical midsagittal slices of fetal heads sampled over a period from 16 to 39 AW. RESULTS: The PCA model brings to light the radial expansion of the forebrain growth (first component) associated with an inferior and posterior rotation of the occipital lobe. The growth of the infratentoriel region presents an inferior and posterior expansion associated with a second component corresponding to inferior and anterior expansions. From the 17 AW, appears an heterochrony between the supra- and infratentorial growths and an inversion of the ratio between the infra- and supratentorial dimensions after 30 AW. The sphenoidal and clivo-foraminal angles decrease slightly until 25 AW, and then increase quickly until the 39 AW. CONCLUSIONS: The growth of brain is accompanied by morphological change between the compartments supra- and infratentoriel but also on the level of the base of skull. The possible interactions will be discussed.

Defining a role for sphingosine kinase 1 in p53-dependent tumors.

p53 is a crucial tumor suppressor that is mutated or deleted in a majority of cancers. Exactly how p53 prevents tumor progression has proved elusive for many years; however, this information is crucial to define targets for chemotherapeutic development that can effectively restore p53 function. Bioactive sphingolipids have recently emerged as important regulators of proliferative, apoptotic and senescent cellular processes. In this study, we demonstrate that the enzyme sphingosine kinase 1 (SK1), a critical enzyme in the regulation of the key bioactive sphingolipids ceramide, sphingosine and sphingosine-1-phosphate (S1P), serves as a key downstream target for p53 action. Our results show that SK1 is proteolysed in response to genotoxic stress in a p53-dependent manner. p53 null mice display elevation of SK1 levels and a tumor-promoting dysregulation of bioactive sphingolipids in which the anti-growth sphingolipid ceramide is decreased and the pro-growth sphingolipid S1P is increased. Importantly, deletion of SK1 in p53 null mice completely abrogated thymic lymphomas in these mice and prolonged their life span by ~30%. Deletion of SK1 also significantly attenuated the formation of other cancers in p53 heterozygote mice. The mechanism of p53 tumor suppression by loss of SK1 is mediated by elevations of sphingosine and ceramide, which in turn were accompanied by increased expression of cell cycle inhibitors and tumor cell senescence. Thus, targeting SK1 may restore sphingolipid homeostasis in p53-dependent tumors and provide insights into novel therapeutic approaches to cancer.

Reduction of azides to amines mediated by tin bis(1,2-benzenedithiolate)

[reaction: see text] A procedure for the conversion of azides to amines, which uses NaBH4 and catalytic amounts of tin(IV) 1,2-benzenedithiolate, is disclosed. Primary, secondary, tertiary, aromatic, and heteroaromatic azides are reduced in excellent yields under very mild conditions.