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Bio-Oss (Geistlich) is composed of anorganic bovine bone and has been widely used in several bone regeneration procedures during oral surgery. However, how this biomaterial enhances osteoblast activity to promote bone formation is not completely understood. MicroRNAs (miRNAs) represent a class of small, functional, noncoding RNAs of 19 to 23 nucleotides that regulate the transcription of messenger RNAs (mRNAs) in proteins. In this study, the miRNA microarray technique was used to investigate translation regulation in an osteoblast-like cell line (MG63) exposed to Bio-Oss. Nine up-regulated miRNAs (mir-423, mir-492, mir-191, mir-23a, mir-377, mir-494, mir-214, mir-193b, mir-320) and 4 down-regulated miRNAs (mir-27a, mir-24, mir-188, let-7c) were identified. Because each miRNA regulates 100 mRNAs, only mRNAs related to bone formation were analyzed. The vast majority of detected mRNAs are down-regulated, including some homeobox genes (genes that regulate the morphogenesis of an entire segment of the body), such as noggin and EN1. An indirect positive effect was demonstrated on bone morphogenetic protein-4. To the authors' knowledge, the data reported here are the first on translation regulation in osteoblasts exposed to Bio-Oss. This study may be relevant in better understanding the molecular mechanism of bone regeneration and used as a potential tool for analyzing the combined use of cytokines. [ABSTRACT FROM AUTHOR]

Diagnosis of focal disease, the theory that the human oral microbial (HOM) could affect the onset and development of systemic diseases, was very popular in the past, but the lack of scientific evidence has led to the abandonment of this idea. Interestingly, increasing evidence over the past 3 or so decades suggests that HOM can indeed serve as a reservoir for systemic dissemination of pathogenic bacteria and their toxins in distant body sites, favouring the developments of malignant tumours. Malignant tumours are complex communities of oncogenically transformed cells with aberrant genomes, associated nonneoplastic cells including immune and stromal cells, and sometimes HOM, including bacteria and viruses. Recent data suggest that HOM and periodontal disease play an active role in the pathogenesis of colorectal cancer, in fact HOM has been found within the colorectal cancer microenvironment, and the composition of the HOM was different from that of adjacent non- neoplastic tissue. An association of fusobacterium nucleatum with the colonic mucosa of colorectal cancer has been proven. Several questions thus arise. Is periodontal disease a risk factor for colorectal carcinoma? Given the connectivity of the digestive tract, could fusubacterium nucleatum or other HOM be involved in additional gastrointestinal disorders? Furthermore, based on the ''mobility'' of Fusubacterium nucleatum and the omnipresence of cadherins, could this organism be involved in cancers beyond the gastrointestinal tract? Answers to these questions will shed new lights on the role of the HOM in onset of diseases. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to classify the phenotypes found in a series of patients with non-syndromic cleft lip (CL) with or without cleft palate (CP) and isolated cleft palate. Additionally, the frequency distribution of cases belonging to families linked to markers on chromosomes 6 and 2 within these phenotypic patterns were estimated.Design: A retrospective examination of all the available affected cases collected in Italy.Setting and Sample Population: Ninety-seven affected subjects aged 5-18 years belonging to 38 families were considered. Patterns were identified by variance of the cleft (lip, primary palate, secondary palate) and stratified according to the side of occurrence (right, left, or bilateral). Latent class analysis was used as main statistical tool for carrying out the results.Results: Three homogenous classes were identified (P < 0.0001) by means of latent class analysis. Individuals were assigned to the most suited class. All three variables (lip, primary and secondary cleft palate) generated a specific class. Optimal findings were reported in cases having 'any isolated cleft lip' (class 1); 'secondary CP with or without bilateral/right primary cleft palate + bilateral/right cleft lip' (class 2); and 'left primary cleft palate + left/bilateral cleft lip with or without secondary CP' (class 3). Correspondence to the evidence of linkage to chromosome 6 showed that 9 of 10 cases presenting with 'right primary CP + right CL with secondary cleft palate' (class 2) belonged to a linked family. The same combination, but occurring on the left side (class 3), revealed that only three of nine cases belong to families linked to chromosome 6 (P-value = 0.02). The two patterns (right and left) never occurred in the same family. Three reliable groups were identified based on laterality and the presence of a cleft. A single right sided pattern displayed a statistically different distribution of linkage to chromosome 6 when compared with the homologous left side.Conclusion: Non-syndromic CL with/without CP can be classified according to laterality that can be under genetic control. [ABSTRACT FROM AUTHOR]

The pathogenesis of cleft lip with or without cleft palate (CL/P) is complex; its onset could be due to the interaction of various genetic and environmental factors. Recently MTHFR functional polymorphisms were found to increase the risk of this common malformation; however, this finding is still debated. We investigated 110 sporadic CL/P patients, their parents and 289 unrelated controls for c.665C>T (commonly known as 677C>T; p.Ala222Val) and c.1286A>C (known as 1298A>C; p.Glu429Ala) polymorphism in the MTHFR gene. Transmission disequilibrium test (TDT) showed no distortion in allele transmission. Nevertheless, association studies revealed significant differences in allele frequencies between mothers of CL/P patients and controls. This work supports the hypothesis that a lower MTHFR enzyme activity in pregnant women, mostly related to the c.665C>T variant form, is responsible for a higher risk of having CL/P affected offspring. © 2004 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]