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1.

Purpose

This study aimed to prospectively characterize toxicity and cosmesis after accelerated partial breast irradiation (APBI) with 3-dimensional conformal radiation therapy (CRT) or single-entry, multilumen, intracavitary brachytherapy.

Methods and materials

A total of 281 patients with pTis, pT1N0, or pT2N0 (≤3.0 cm) breast cancer treated with segmental mastectomy were prospectively enrolled from December 2008 through August 2014. APBI was delivered using 3-dimensional CRT (n = 29) or with SAVI (n = 176), Contura (n = 56), or MammoSite (n = 20) brachytherapy catheters. Patients were evaluated at protocol-specified intervals, at which time the radiation oncologist scored cosmetic outcome, toxicities, and recurrence status using a standardized template.

Results

The median follow-up time is 41 months. Grade 1 seroma and fibrosis were more common with brachytherapy than with 3-dimensional CRT (50.4% vs 3.4% for seroma; P < .0001 and 66.3% vs 44.8% for fibrosis; P = .02), but grade 1 edema was more common with 3-dimensional CRT than with brachytherapy (17.2% vs 5.6%; P = .04). Grade 2 to 3 pain was more common with 3-dimensional CRT (17.2% vs 5.2%; P = .03). Actuarial 5-year rates of fair or poor radiation oncologist-reported cosmetic outcome were 9% for 3-dimensional CRT and 24% for brachytherapy (P = .13). Brachytherapy was significantly associated with inferior cosmesis on mixed model analysis (P = .003). Significant predictors of reduced risk of adverse cosmetic outcome after brachytherapy were D0.1cc (skin) ≤102%, minimum skin distance >5.1 mm, dose homogeneity index >0.54, and volume of nonconformance ≤0.89 cc. The 5-year ipsilateral breast recurrence was 4.3% for brachytherapy and 4.2% for 3-dimensional CRT APBI patients (P = .95).

Conclusions

Brachytherapy APBI is associated with higher rates of grade 1 fibrosis and seroma than 3-dimensional CRT but lower rates of grade 1 edema and grade 2 to 3 pain than 3-dimensional CRT. Rates of radiation oncologist-reported fair or poor cosmetic outcomes are higher with brachytherapy. We identified dosimetric parameters that predict reduced risk of adverse cosmetic outcome after brachytherapy-based APBI. Ipsilateral breast recurrence was equivalent for brachytherapy and 3-dimensional CRT.  相似文献   
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Systemic AA amyloidosis is a serious complication of many chronic inflammatory disorders and chronic infections. Renal involvement is seen in the majority of the patients and can lead to end‐stage renal disease. Renal transplantation can be performed in these patients; however, amyloidosis can recur in the transplanted kidneys. On the other hand, de novo AA amyloidosis in renal transplant patients has been rarely reported. We report a 17‐yr‐old patient with end‐stage renal disease due to genitourinary anomalies who developed recurrent pyelonephritis after transplantation. Three yr after transplantation, renal biopsy was performed for proteinuria and AA amyloidosis was identified in the renal allograft. Although rare, chronic infections might cause de novo amyloidosis in renal transplant patients. Therefore, amyloidosis should be kept in mind in those types of patients who present with proteinuria.  相似文献   
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BACKGROUND: Papillon-Lefèvre Syndrome (PLS) is an autosomal recessive disease characterized by palmoplantar hyperkeratosis and severe periodontitis affecting both primary and secondary dentitions. Cathepsin C (CTSC) gene mutations are etiologic for PLS. The resultant loss of CTSC function is responsible for the severe periodontal destruction seen clinically. METHODS: A 4-year-old female (case 1) and her 10-year-old sister (case 2) presented with palmoplantar skin lesions, tooth mobility, and advanced periodontitis. Based on clinical findings, the cases were diagnosed with PLS. Mutational screening of the CTSC gene was conducted for the cases, and their clinically unaffected parents and brother. Biochemical analysis was performed for CTSC, cathepsin G (CTSG), and elastase activity in neutrophils for all members of the nuclear family. The initial treatment included oral hygiene instruction, scaling and root planing, and systemic amoxicillin-metronidazole therapy. RESULTS: CTSC mutational screening identified a c.415G>A transition mutation. In the homozygous state, this mutation was associated with an almost complete loss of activity of CTSC, CTSG, and elastase. Although monthly visits, including scaling, polishing, and 0.2% chlorhexidine digluconate irrigation were performed to stabilize the periodontal condition, case 1 lost all her primary teeth. In case 2, some of the permanent teeth could be maintained. CONCLUSIONS: This report describes two siblings with a cathepsin C gene mutation that is associated with the inactivity of cathepsin C and several neutrophil serine proteases. The failure of patients to respond to periodontal treatment is discussed in the context of these biological findings.  相似文献   
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Radicular cysts (RCs) are the most common inflammatory jaw cystic lesions that occur infected and necrotic in teeth pulps. They account for more than 50% of all odontogenic cysts. Radicular cysts cause slowly progressive painless swelling. There are no symptoms until they become large. Enucleating the cyst is recommended with primary treatment. Here we describe a patient with a large RC with maxillary sinus involvement who underwent an endonasal endoscopic approach for complete resection. In conclusion, the endonasal endoscopic approach should be kept in mind for the resection of RC with maxillary sinus involvement because of its minimally invasive characteristics.  相似文献   
8.
This study investigated the polymerization shrinkage of restorative materials and microleakage in the proximal box of Class II restorations. Twenty caries free extracted human molars were prepared on the mesial and distal, making 40 slot cavities. Groups (n=10) were classified as: Group 1: Single bond/Filtek Z-250; Group 2: Single Bond/Filtek Flow/Filtek Z-250; Group 3: Admira Bond/Admira; Group 4: Ariston Liner/Ariston. Dentin bonding systems and resin composites were applied according to the manufacturer's instructions. The specimens were stored in distilled water for one week at 37 degrees C, thermocycled (5 degrees-55 degrees C x 2000), stained with 50% aqueous silver nitrate, immersed in a diluted developer solution (24 hours), rinsed and sectioned in two pieces with a low speed saw (Isomet). Dye penetration (Score 0-4) was determined separately at the occlusal enamel margin and cementoenamel junction. The volumetric polymerization shrinkage of materials was determined with the apparatus of Watts and Cash (Watts Cash, 1991) for 300 seconds. Polymerization shrinkage results were as follows: Filtek Flow (3.5% +/- 0.1) > Admira (2.1% +/- 0.1) = Ariston AT (2.3% +/- 0.1) > Filtek Z-250 (1.8% +/- 0.1) (One-way Anova, post hoc Bonferroni test at p = 0.05 level). No statistical difference was found at the enamel margins for any of the materials (Score 0-1). At the cemento-enamel junction, all test groups showed significantly higher microleakage when compared to the enamel margins (Kruskal-Wallis test, Mann-Whitney U). Dye penetration results at dentin were as follows: Filtek Flow + Filtek Z-250 = Admira < Ariston AT = Filtek Z-250. microleakage than the ion-releasing and hybrid composites lined only with bonding agent at the cementoenamel junction in Class II cavities.  相似文献   
9.
A facial defect results in cosmetic, functional, and psychologic problems and acts as a difficult and challenging procedure for the maxillofacial surgeon and the prosthodontist. Retention of a facial prosthesis is an important key in the patient's satisfaction and acceptance. The introduction of extraoral implant applications have been accepted as an advanced retention method. The purpose of this article is to report the results from our clinical experience with patients wearing facial prostheses anchored to extraoral ITI implants (Straumann, AG, Basel, Switzerland).  相似文献   
10.

Objective

This study evaluated the ability of benzalkonium chloride (BAC) to bind to dentine and to inhibit soluble recombinant MMPs and bound dentine matrix metalloproteinases (MMPs).

Methods

Dentine powder was prepared from extracted human molars. Half was left mineralized; the other half was completely demineralized. The binding of BAC to dentine powder was followed by measuring changes in the supernatant concentration using UV spectrometry. The inhibitory effects of BAC on rhMMP-2, -8 and -9 were followed using a commercially available in vitro proteolytic assay. Matrix-bound endogenous MMP-activity was evaluated in completely demineralized beams. Each beam was either dipped into BAC and then dropped into 1 mL of a complete medium (CM) or they were placed in 1 mL of CM containing BAC for 30 days. After 30 days, changes in the dry mass of the beams or in the hydroxyproline (HYP) content of hydrolysates of the media were quantitated as indirect measures of matrix collagen hydrolysis by MMPs.

Results

Demineralized dentine powder took up 10-times more BAC than did mineralized powder. Water rinsing removed about 50% of the bound BAC, whilst rinsing with 0.5 M NaCl removed more than 90% of the bound BAC. BAC concentrations 0.5 wt% produced 100% inhibition of soluble recombinant MMP-2, -8 or -9, and inhibited matrix-bound MMPs between 55 and 66% when measured as mass loss or 76-81% when measured as solubilization of collagen peptide fragments.

Conclusions

BAC is effective at inhibiting both soluble recombinant MMPs and matrix-bound dentine MMPs in the absence of resins.  相似文献   
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