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21.
Neurodevelopmental delay and intellectual disability (ID) can arise from numerous genetic defects. To date, variants in the EXOSC gene family have been associated with such disorders. Using next-generation sequencing (NGS), known and novel variants in this gene family causing autosomal recessive ID (ARID) have been identified in five Iranian families. By collecting clinical information on these families and comparing their phenotypes with previously reported patients, we further describe the clinical variability of ARID resulting from alterations in the EXOSC gene family, and emphasize the role of RNA processing dysregulation in ARID.  相似文献   
22.
The union of two different dental sprouts which can happen in any phase of dental development is commonly called fusion. This developmental anomaly may cause clinical problems including esthetic impairment, which are mainly treated by endodontic and surgical treatments. There are a few reports of conservative not invasive treatment of fused incisors teeth through restorative or prosthetic techniques. They are rarely reported in mandibular posterior teeth. This paper presents an unusual case of fusion of 7 and 8, and also 9 and 10 teeth which was treated with a nonendodontic and nonsurgical conservative approach. Patient was a healthy18-year-old female with chief complaint of bad-looking teeth that in intraoral examination revealed the fusion of 7 and 8, and also 9 and 10 teeth. The space between the mesial of the 6 and 11 teeth was reconstructed. Diastema between the fused teeth was closed. A new lateral tooth was replaced between the fused teeth (7 and 8) and 6 tooth with direct fiber-reinforced composite. The space between the fused teeth (9 and 10) and also tooth 11 was partially closed. Gingival papillas were reconstructed using pink composite. The mandibular anterior missing teeth were replaced with rochett bridge. At the end of treatment the esthetic of the patient was improved. As the treatment was not invasive, major complications are not expected; however, there is potential for eventual long-term periodontal problems due to poor oral hygiene. Debonding of the rochett bridge may happen as well.  相似文献   
23.
In this paper, a microwave microscope is presented for characterization of skin abnormalities. A coplanar waveguide probe is designed and fabricated for high-resolution near-field imaging of the biological samples. Several simulations and measurement studies are described to present the capability of the proposed probe in identification of different tissues and the detection of fat masses at different depths. In addition, two methods are used to eliminate the measurement noise which is caused by non-targeted tissues. Then, the contours around the masses are obtained applying an edge detection method. The measurement results show that the proposed probe can detect the fat masses with amplitude contrast about 15 dB at a λ/10 (at 14.36 GHz) standoff distance. The proposed microscope is easy to fabricate, and provides a low-cost solution for fast and accurate skin cancer detection of abnormalities in human body such as early detection of small tumors in breast or skin cancers.  相似文献   
24.

Objective

A systematic characterization of hybrid scaffolds, fabricated based on combinatorial additive manufacturing technique and freeze-drying method, is presented as a new platform for osteoblastic differentiation of dental pulp cells (DPCs).

Methods

The scaffolds were consisted of a collagenous matrix embedded in a 3D-printed beta-tricalcium phosphate (β-TCP) as the mineral phase. The developed construct design was intended to achieve mechanical robustness owing to 3D-printed β-TCP scaffold, and biologically active 3D cell culture matrix pertaining to the Collagen extracellular matrix. The β-TCP precursor formulations were investigated for their flow-ability at various temperatures, which optimized for fabrication of 3D printed scaffolds with interconnected porosity. The hybrid constructs were characterized by 3D laser scanning microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and compressive strength testing.

Results

The in vitro characterization of scaffolds revealed that the hybrid β-TCP/Collagen constructs offer superior DPCs proliferation and alkaline phosphatase (ALP) activity compared to the 3D-printed β-TCP scaffold over three weeks. Moreover, it was found that the incorporation of TCP into the Collagen matrix improves the ALP activity.

Significance

The presented results converge to suggest the developed 3D-printed β-TCP/Collagen hybrid constructs as a new platform for osteoblastic differentiation of DPCs for craniomaxillofacial bone regeneration.  相似文献   
25.
Insulin resistance in chronic hepatitis B and C.   总被引:6,自引:0,他引:6  
AIM: To determine whether insulin resistance occurs in patients with chronic hepatitis B (CHB) and chronic hepatitis C (CHC) and its relationship with the presence of liver fibrosis and steatosis. METHODS: Untreated patients with CHC (n=60) or CHB (n=40), similar in age, gender, body mass index and waist-hip ratio, were studied. Relationship between anthropometric, biochemical (fasting serum insulin, C-peptide, ferritin, iron, TNF-alpha, cholesterol, triglyceride, bilirubin, hemoglobin and platelet concentrations) and liver biopsy (43 CHC and 20 CHB patients) findings was investigated by insulin resistance determined via the homeostasis model assessment (HOMA-IR). RESULTS: The mean fasting serum insulin was 14.9 (11.9) mU/mL in CHC and 21.4 (17.4) in the CHB group (normal range 0.7-9; p=0.049) and mean HOMA-IR was 3.1 (2.6) in CHC versus 4.7 (4.1) in the CHB group (normal range 0.12-4.61; p=0.036). HOMA-IR was significantly associated with fibrosis stage in the CHC group (p=0.015), but not in the CHB group. CONCLUSION: Hyperinsulinemia occurs in chronic viral hepatitis B and hepatitis C; insulin resistance is associated with stage of fibrosis in hepatitis C.  相似文献   
26.
The main intention of this article was to evaluate the reliability of root dentine translucency (RDT) and the width of cementum (CW) in indicating the age over 55 years in forensic and criminal investigations. 600 non-restored, single rooted teeth (300 males and 300 females) which were extracted for periodontal or orthodontic reasons were collected. Each tooth was sectioned longitudinally until the desired thickness (250 µm) was obtained. Both the length of the RDT and CW were measured from these unstained ground sections of teeth using ImageJ computer software. Pearson’s correlation coefficient indicated a very strong and positive correlation for RDW and CW with age in both sexes. Cut-off values of RDT= 7.07 and CW= 52.06 were obtained using the maximum Youden’s index. The value for the area under the curve (AUC) was 0.987 for RDT and 0.910 for CW was seen as indicating a very high discrimination. The performance of these cut-off values was tested in a separate sample of sectioned teeth (n= 300) and was analyzed using contingency tables in both sexes. The sensitivity was 88.2% and 92.3%, while specificity was 98.9% for RDT in males and females. For CW, the sensitivity was 96.1% and 90.3%, and specificity was 76.7% and 74.4% in males and females, respectively. Bayes post-test probability was 98.9% for RDT in both sexes, while 80.5% in males and 78% in females, for CW. Based on our study findings, it can be concluded that both variables have performed well in predicting the age over 55 years. Further research concerning the radiographic study of secondary dentine deposition to predict legal age thresholds would be a great benefit for living adults who require age estimation in civil proceedings.  相似文献   
27.
BACKGROUND AND OBJECTIVE: An observational case series to assess the value of positron emission tomography (PET) in staging ocular adnexal lymphomas and evaluating their response to therapy. PATIENTS AND METHODS: The clinical records of 16 consecutive patients with ocular adnexal lymphoma for whom pretreatment and posttreatment PET scans and corresponding computed tomography (CT) and magnetic resonance imaging (MRI) scans were available were compared. RESULTS: Pretreatment PET scans demonstrated fluorine 18-fluorodeoxyglucose (FDG) positive lesions in 15 orbits of 12 patients. In 1 patient with low-grade follicular lymphoma of the orbit, PET revealed an additional focus of lymphoma in the deltoid muscle that was missed on clinical examination and conventional radiography. All of the posttreatment PET scans showed complete resolution of FDG uptake, suggesting good response to therapy. However, posttreatment CT and MRI scans demonstrated residual masses in 3 patients. CONCLUSIONS: PET is valuable for initial staging of ocular adnexal lymphomas and may be a good adjunct to conventional imaging in evaluation of response to therapy.  相似文献   
28.
Relapsing polychondritis is rare in rheumatoid arthritis (RA). We report a case of classical RA with relapsing polychondritis. Nasal septal chondritis resulted in cartilage collapse and a characteristic saddle nose deformity. HLA typing of the patient showed the presence of HLA-DR4 antigen.  相似文献   
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