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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]

Nonsyndromic cleft lip with or without cleft palate (CL/P) is a complex genetic trait and little is known about its aetiology. Recent investigations on rare clefting syndromes provided interesting clues about genes involved in face development. The PVRL1 gene encodes nectin1, a cell-to-cell adhesion molecule. Mutations in its sequence have been shown to cause the rare autosomal recessive syndrome CL/P-ectodermal dysplasia syndrome (CLPED1), while heterozygosity for the mutation W185X seemed to increase the risk of non syndromic CL/P in a population from northern Venezuela. In the present study, we screened 143 Italian CL/P patients for mutations in PVRL1. Three rare sequence variants in exon 3 that create amino-acid changes were detected in a total of 7 patients. Two of these mutations were not found in a panel of 292 unaffected controls, while the third was found in two controls. This study describes new mutations that may represent genetic risk factors for CL/P. Even though a study to look at the effects of the mutations on nectin1 function was not feasible, supporting evidence was reported, thus confirming the involvement of PVRL1 in the aetiology of non-syndromic CL/P malformation. [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]

Nonsyndromic cleft lip with or without cleft palate (CL/P) is the most common orofacial malformation, having a non-Mendelian and multifactorial aetiology. It has been shown that polymorphic variants of genes encoding key proteins of folate and methionine metabolism might be important maternal risk factors for having a child with these craniofacial anomalies. The aim of this study was to evaluate the role of two polymorphisms of the methylenetetrahydrofolate dehydrogenase 1 ( MTHFD1) gene, the A1958G and the G401A variants, on the risk of CL/P in the Italian population. A1958G and G401A polymorphism genotyping of MTHFD1 was performed on 216 CL/P triads, (patient and parents), for this study by restriction endonuclease digestion of PCR products. Linkage disequilibrium between markers and disease was tested using both pairwise and haplotype analyses. In our case-parents triad design no significant association between MTHFD1 and the disease is evident. Our data do not support MTHFD1 involvement in CL/P onset among the Italian population. [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]