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81.
Multiple primary malignant neoplasms (MPMN) are rare tumors that
have attracted attention with increasing incidence rates in recent years and where
cancer susceptibility genes may play a role in their etiology. In this study, it was
aimed to determine the genotype-phenotype correlation in patients with MPMN.
From January 2018 to January 2020, thirty patients were analyzed for 59 cancer
susceptibility genes and diagnosed with MPMN, using a large multigene panel
with Next Generation Sequencing technique (NGS) in Turkey. The mean age of
first and second cancer diagnosis of cases were calculated as 42.5 and 49.9
(respectively). These primary cancers were frequently detected in the colon and
breast, and the interval between diagnosis was 89 months. In 9 of the patients
(30%); BRCA2, MSH6, MLH1, MUTYH, and ATM were detected as causal genes.
Relatives with cancer of MPMN patients with causative gene carriers were
detected in higher numbers than non-carrier. According to the logistic regression
model applied, patients with at least 1 relatives with cancer were found to have a
0.38-fold increased risk of being a causal gene variant carrier. Hereditary cancer
susceptibility genes may play an important role in the etiology of MPMN. In
MPMN cases, detection of the causal gene by genetic analysis; It will enable not
only to ensure a complete and accurate diagnosis of the sick individual and to
plan the treatment properly, but also to include the carriers’ relatives in the
intensive cancer screening, monitoring, and prevention program. 相似文献
82.
Muhammed H. Arikan Fatih Eroglu Volkan Eskizeybek Emine Feyza Sukur Mehmet Yildiz Hatice S. Sas 《Materials》2022,15(2)
Aerospace-grade composite parts can be manufactured using Vacuum Bag Only prepregs through an accurate process design. Quality in the desired part can be realized by following process modeling, process optimization, and validation, which strongly depend on a primary and systematic material characterization methodology of the prepreg system and material constitutive behavior. The present study introduces a systematic characterization approach of a Vacuum Bag Only prepreg by covering the relevant material properties in an integrated manner with the process mechanisms of fluid flow, consolidation, and heat transfer. The characterization recipe is practiced under the categories of (i) resin system, (ii) fiber architecture, and (iii) thermal behavior. First, empirical models are successively developed for the cure-kinetics, glass transition temperature, and viscosity for the resin system. Then, the fiber architecture of the uncured prepreg system is identified with X-ray tomography to obtain the air permeability. Finally, the thermal characteristics of the prepreg and its constituents are experimentally characterized by adopting a novel specimen preparation technique for the specific heat capacity and thermal conductivity. Thus, this systematic approach is designed to provide the material data to process modeling with the motivation of a robust and integrated Vacuum Bag Only process design. 相似文献
83.
84.
Contribution of diffusion‐weighted imaging to dynamic contrast‐enhanced MRI in the characterization of papillary breast lesions 下载免费PDF全文
Seyma Yildiz MD Huseyin Toprak MD Yeliz Emine Ersoy MD Fatma Ümit Malya MD Ayşe Ahsen Bakan MD Ayşe Aralaşmak MD Zuhal Gucin MD 《The breast journal》2018,24(2):176-179
Papillary lesions have a broad spectrum of appearances on magnetic resonance imaging (MRI ). The purpose of this study was to evaluate whether apparent diffusion coefficient (ADC ) values of papillary lesions can be used to characterize lesion as benign or malignant. This retrospective study included 29 papillary lesions. Diagnostic values of dynamic contrast‐enhanced MRI (DCE‐MRI), DWI ‐ADC , and DCE ‐MRI plus DWI ‐ADC were separately calculated. The malignant papillary lesions (0.744×10?3 mm2/s) exhibited significantly lower mean ADC values than the benign lesions (1.339×10?3 mm2/s). Addition of DWI to standard DCE ‐MRI provided 100% sensitivity. We hypothesized that this combination may prevent unnecessary excisional biopsies. 相似文献
85.
Suna Kose Ozkan Karaman Huray Islekel Nevin Uzuner Arzu Babayigit Duygu Olmez Zekiye Altun Sule Turgut Dilek Tezcan 《Allergy and asthma proceedings》2007,28(2):199-203
The aim of this study was to evaluate respiratory function tests, total eosinophil counts, serum immune globulin E (IgE), and serum concentrations of soluble intercellular adhesion molecule (sICAM)1, soluble vascular cell adhesion molecule (sVCAM) 1, and soluble P-selectin (sP-selectin) levels in the children with mild and/or moderate asthma before and 3 months after inhaled steroids and to determine whether adhesion molecule levels showed any difference between asthmatic and healthy children and whether these levels changed with disease activity. A total of 28 children with bronchial asthma and 24 children as a control group were included in the study. All of the patients in the study group were administered inhaled budesonide treatment. The patients were reevaluated 3 months later. Respiratory functions tests were performed and total eosinophil count and serum total IgE level were determined. Serum levels of sICAM-1, sVCAM-1, and sP-selectin were determined and skin-prick tests were performed. Significant difference paralleled to clinical improvement was found in the study group for respiratory function tests, total eosinophil count, serum IgE level, and sICAM-1 levels determined before and after the treatment. However, no significant difference was found for sP-selectin and sVCAM-1 levels before and after the treatment. The higher level of sICAM-1 before the treatment suggests that leukocyte-endothelial adhesion have a role in bronchial asthma, which is an inflammatory airway disease. Reduction in the level of sICAM-1 after the treatment may be related to the decreased inflammation in response to therapy. However, no strong relationships were found between the determinants representing the inflammation and respiratory function tests. 相似文献
86.
87.
Leman Kaya Emine amtosun Ayehan Aknc Rfat Bircan 《Journal of clinical research in pediatric endocrinology》2022,14(1):114
An activating variant of the thyroid stimulating hormone receptor (TSHR) gene is one of the rare causes of neonatal hyperthyroidism. This disorder may occur as a result of an autosomal dominant inheritance or sporadically through de novo variation. Here we present a case of neonatal onset congenital non-autoimmune hyperthyroidism (NAH) with a sporadic germline activating TSHRV656F variant. A female infant with tachycardia, who was transferred due to hyperthyroidism in the first week of life, displayed no other symptoms or signs. The patient’s mother did not have Graves’ disease, and TSHR stimulating antibodies were not present in the mother or baby. Imaging showed thyroid gland hyperplasia and left ventricular hypertrophy, the patient was subsequently put on methimazole treatment. After six months undergoing treatment, a heterozygous p.Val656Phe (V656F) (c.1966G>T) variant was detected on exon 10 of the TSHR gene. The variant was not identified in the mother and father, so the case was assumed to be sporadic. In conclusion, although the literature describes V656F variant as a somatic variant in children and adults with toxic thyroid nodule(s) that results in the structural activation of the TSH receptor, no previous cases of neonatal hyperthyroidism due to TSHRV656F variant have been reported. This study is the first case review that highlights the relationship between TSHRV656F variant and neonatal onset NAH. 相似文献
88.
Objective:To evaluate the effect of different bracket types on the levels of Streptococcus mutans (SM) and Lactobacillus (LB) in saliva, in plaque, and on the periodontal condition.Materials and Methods:Forty patients aged 14 to 16 years, who had Angle Class I malocclusion with minimal crowding, were nonsmokers, were without systematic disease, and did not use antibiotics or oral mouth rinses during the 3-month period before the study were randomly selected. The patients were subdivided into two groups with random allocation of bracket type: conventional brackets (CB; Avex Mx, OPAL orth.) with steel wire ligature or self-ligating brackets (SLB; F1000, Leone S.p.A.). Microbial and periodontal records were obtained before bonding (T1) and 1 month after bonding (T2). Microbial samples were collected from the stimulated saliva and the plaque from the labial surfaces of the upper and lower lateral incisors. To estimate the number of colony-forming units of SM and LB, Dentocult SM and LB kits were used. The plaque index (PI), gingival index (GI), and pocket depth (PD) values were recorded to evaluate the periodontal condition. Paired t-test and Mann-Whitney U-test were used to compare the groups statistically.Results:No significant differences occurred in SM or LB colonization between the groups. In the SLB group, PI, GI, and PD values increased significantly (P < .05). A greater increase was found in PD value in the SLB group (0.98 mm) compared with the CB group (0.04 mm; P < .05).Conclusions:The F1000 SLB do not have an advantage over Avex Mx CB with respect to periodontal status and colonization of SM and LB. 相似文献
89.
Effect of Non‐Surgical Periodontal Treatment on Gingival Crevicular Fluid and Serum Endocan,Vascular Endothelial Growth Factor‐A,and Tumor Necrosis Factor‐Alpha Levels 下载免费PDF全文
Background: Periodontitis is a chronic inflammatory disease that occurs due to the interaction between pathogenic microorganisms and host defenses. Endocan is a proteoglycan secreted by endothelial cells under the control of inflammatory cytokines. Aims of the study are to determine serum and gingival crevicular fluid (GCF) endocan levels in the pathogenesis of periodontal diseases, supported with vascular endothelial growth factor (VEGF‐A) and tumor necrosis factor (TNF)‐alpha levels. This study additionally aims to evaluate correlation between GCF endocan levels, VEGF‐A, and TNF‐α levels with periodontal probing depth (PD). Methods: The study consists of two groups: group 1 (n = 20), healthy individuals; group 2 (n = 20), individuals with generalized chronic periodontitis (CP). Clinical measurements were recorded; GCF and serum samples were obtained from each participant before and 6 weeks after therapy. Levels of biomarkers were measured by enzyme‐linked immunosorbent assay. Intergroup comparisons of biochemical and clinical parameters were analyzed by Kruskal–Wallis/Bonferroni‐adjusted Mann–Whitney U test using statistical software. Results: Serum and GCF endocan, VEGF‐A, and TNF‐α levels were significantly higher in patients with CP than in healthy individuals (P <0.001) and decreased after treatment (P <0.03). A significant correlation was observed between GCF TNF‐α and PD (4 mm ≤ PD ≤5 mm and PD ≥6 mm). A significant relationship was found among GCF endocan and TNF‐α, VEGF‐A, CAL, and GI for all groups (P <0.05). Conclusions: Endocan and TNF‐α levels, both in GCF and serum, increased from health to periodontitis and decreased with non‐surgical periodontal treatment. Within the limits of the study, endocan may be considered as a potential inflammatory marker for periodontal disease. 相似文献
90.
Yazici AR Tuncer D Dayangaç B Ozgünaltay G Onen A 《The journal of adhesive dentistry》2007,9(3):305-309
PURPOSE: To evaluate the effect of saliva contamination on the microleakage of an etch-and-rinse adhesive and a self-etching adhesive. MATERIALS AND METHODS: Class V cavity preparations at the cementoenamel junction were made on the buccal and lingual surfaces of 40 freshly extracted human molars. The teeth were randomly assigned into two groups for different adhesives: Group I, Single Bond (two-step etch-and-rinse adhesive) and Group II, Futura Bond NR (one-step self-etching adhesive). The adhesive materials were applied according to their manufacturers' recommendations. The specimens were then further subdivided into five subgroups (A-E; n = 8): group A, contamination before adhesive curing; group B, contamination before adhesive curing and re-application of adhesive; group C, contamination after adhesive curing; group D, contamination after adhesive curing and re-application of adhesive; and group E, no contamination (control). Contamination of adhesive surfaces was performed with fresh natural saliva and the saliva was removed by a gentle air blast. The specimens were restored with Z250 hybrid composite. After thermocycling (500x, 5 degrees C to 55 degrees C) and immersion in 0.5% basic fuchsin, the dye penetration was evaluated under a stereomicroscope. Statistical analysis was performed with the Kruskal-Wallis test at p < 0.05. RESULTS: No statistically significant differences were found among the contamination subgroups on the enamel or on the dentin for either group (p > 0.05). There was no significant difference in leakage between Group I and Group II for any subgroup (p > 0.05). CONCLUSION: Contamination of adhesives with saliva before and after adhesive curing did not worsen the microleakage of the two-step etch-and-rinse adhesive Single Bond or the one-step self-etching adhesive Futura Bond NR. 相似文献