In a fraction of families fulfilling the Amsterdam criteria for hereditary non-polyposis colorectal cancer, colorectal cancers are microsatellite stable and DNA mismatch repair gene (MMR) mutations are not found. These families were designated as familial colorectal cancer type X (FCCTX). We aimed to characterise a group of FCCTX families defined by the Amsterdam criteria and MSS tumours at clinical and molecular level. Twenty-four tumours from 15 FCCTX families were analysed for loss of known tumour suppressor gene (TSG) loci (APC, TP53, SMAD4 and DCC), MGMT and MMR genes promoter methylation, and also APC and KRAS somatic mutations. FCCTX families presented specific clinical features: absence of endometrial tumours, high adenoma/carcinoma ratio (1.91) and prevalence of rectal cancers (13/27, 48%). New molecular features were found: the majority of FCCTX tumours (13/18; 72%) presented TSG loss. TSG loss positive tumours presented frequent APC and KRAS somatic mutations and MGMT methylation [10/13 (77%), 7/13 (54%) and 6/11 (54%), respectively]. In TSG loss negative tumours (5/18; 28%), the same molecular events were found in 2/5 (40%), 2/5 (40%) and 1/3 (33%) tumours, respectively. Transition mutations in KRAS were more frequent among MGMT methylated tumours than in unmethylated [5/8 (63%) vs. 1/10 (10%), P = 0.03]. Although sharing similar clinical features, at least two different molecular entities should exist among FCCTX families, one whose tumours present frequent TSG loss, APC and KRAS somatic mutations, and MGMT promoter methylation, and a second, lesser predominant, with no evidence of TSG loss and rarely presenting promoter methylation.

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Preservation of the alveolar bone is a determinant in the outcome of orthodontic treatment. Alveolar bone defects or a decrease of their height and width may occur due to common reasons such as inflammation, tooth extraction, or cleft lip and palate. The aim of this systematic review was to investigate and appraise the quality of the most up to date available evidence regarding the applications and effects of platelet-rich fibrin (PRF) in orthodontics. This study was carried out according to preferred reporting items for systematic reviews and meta-analyses guidelines using the following databases: Medline via PubMed, Cochrane Library, Web of Science Core Collection and EMBASE. The qualitative assessment of the included studies was performed using Cochrane Risk of Bias tool and ROBINS-I guidelines. Results: From a total of 489 studies, nine studies were selected. The majority of the included studies demonstrate that autogenous anterior iliac graft with PRF had a higher amount of newly formed bone. Furthermore, this review also suggests that the application of platelet derivatives in the extraction socket can accelerate orthodontic tooth movement. Despite the limitations in the included studies, this systematic review suggested that PRF can improve alveolar cleft reconstruction and orthodontic tooth movement.

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Adenomas diagnosed before aged 40 years presented microsatellite instability only in patients from families with clinical criteria for Lynch syndrome. According to our results, to detect new cases of Lynch syndrome, family history is more important than microsatellite instability testing in adenomas from young patients.

In 1997 Bethesda Guidelines (BG) were established and in 2004 those criteria were revised (RBG), with the main goal of selecting colorectal cancers (CRC) that should be subjected to microsatellite instability (MSI) testing. High microsatellite instability (MSI-H) is an intermediate marker for mutational analysis of the mismatch repair (MMR) genes involved in the genesis of Lynch Syndrome (LS). We aimed to evaluate and compare BG/RBG in the detection of MSI-H and subsequent identification of pathogenic MMR genes mutations. We included 174 patients with CRC and indication for MSI analysis according to BG or RBG. MSI testing was performed with the Bethesda markers and mutational analysis of MLH1, MSH2 and MSH6 genes undertaken with DGGE, MLPA and direct sequencing. One hundred fourteen of 174 patients (65.5 %) fulfilled BG and all of them RBG. With the BG, MSI-H was detected in 37/114 (32.5 %) CRCs and mutational analysis was positive in 14/37 (37.8 %) patients. The RBG led to detection of MSI-H in 49/174 (28.2 %) of the CRCs, having the mutational analysis been positive in 16/49 (32.7 %) patients. We could identify 14/114 (12.3 %) new cases of LS, through BG and 16/174 (9.2 %) via RBG. BG presented a similar overall percentage for the detection of MSI-H and mutations when compared with RBG. RBG implicated the analysis of more patients, though they gave rise to detection of two additional LS cases. This difference has a significant impact on the establishment of preventive measures, mainly for CRC, in all the mutation-carriers belonging to these families.

Background: Cleft lip and palate (CLP) can affect the development of the maxilla; which may create a midfacial deficiency as well as an interference of the facial growth pattern and dentofacial esthetics. Objective: This study aimed to estimate the chronological age of complete fusion of the spheno-occipital synchondrosis (SOS) in cleft lip and palate patients and a control group; using cone beam computed tomography (CBCT) images. Methods: In this retrospective study; 125 patients were enrolled (cleft lip and palate group (n = 91); control group (n = 34)). Age comparison was made with a chi-square test; and a Kaplan–Meier analysis determined the median time to reach complete fusion of the spheno-occipital synchondrosis (p < 0.05). Results: The experimental group showed statistically significant differences in the median time for complete ossification between males and females (p = 0.019). The median time for complete ossification of the spheno-occipital synchondrosis was; for males; 15.0 years in both groups; for females; it was 14.0 years and 13.0 years in the experimental group and in the control group; respectively. Both for males and females; there were no statistically significant differences between experimental and control groups (p = 0.104). Conclusions: The present study showed no differences in the ossification of the spheno-occipital synchondrosis between individuals with and without cleft lip and/or palate.

BACKGROUND Hereditary nonpolyposis colorectal carcinoma (HNPCC) significantly raises the risk of developing colorectal carcinoma (CRC) and other extracolonic tumors. It is defined by the Amsterdam Criteria and is associated with germline mutations in mismatch repair genes, primarily MLH1 and MSH2. The objectives of the current study were to evaluate the presence of CRC (Type I) and other extracolonic tumors (Type II) in families with HNPCC and to analyze the findings for correlations with germline mutations in the MLH1 and MSH2 genes. METHODS Seventy families with an HNPCC diagnosis were analyzed. Denaturing gradient gel electrophoresis and direct sequencing were used for germline mutation analysis in the MLH1 and MSH2 genes. RESULTS Forty‐three of 70 families (61%) presented with HNPCC Type II. In 21 of 30 families that had a complete genetic diagnosis, 16 pathogenic germline mutations (7 MLH1 mutations and 9 MSH2 mutations) and 5 mutations of unknown pathogenecity (all MLH1 mutations) were found. In the remaining nine families, no mutations were detected. Unequivocally pathogenic mutations were far more common in families with HNPCC Type II compared with families that had CRC only (P = 0.01). Families with endometrial carcinoma presented with the greatest probability of mutational detection (P = 0.005). MLH1 was only gene affected in families with HNPCC Type I, whereas mutations in both MLH1 and MSH2 were found in families with HNPCC Type II (P = 0.04). However, the MSH2 gene was more frequently involved in families with HNPCC in which endometrial carcinoma was present (P = 0.005). CONCLUSIONS CRC and endometrial carcinoma were associated with a greater probability of detecting pathogenic mutations in mismatch repair genes, with MSH2 involvement predominating. The results support specific mutational screening strategies, based on observed phenotypes, for families with HNPCC. Cancer 2004. © 2004 American Cancer Society.