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71.
72.

Objectives

To evaluate the management and outcome of children with pheochromocytoma and determine the role of cortex preservation in cases of bilateral disease.

Methods

Retrospective review of children, below 12 y of age, with pheochromocytoma managed between November 2003 and December 2012 was done.

Results

Twelve patients, nine boys and three girls with median age 9 y were enroled. Eleven (92 %) had adrenal tumors and in one it was extra-adrenal. Five (42 %) had bilateral disease. Ten presented with hypertension, one with headache and one with abdominal pain and fever. All were stabilized pre-operatively with alpha and beta blockers and volume expansion. Six children with unilateral disease underwent total adrenalectomy. Out of five with bilateral disease, one child underwent bilateral total adrenalectomy and was later started on hormone replacement. Remaining four underwent total adrenalectomy on one side and partial on the other side. Post-operatively all became symptom free and normotensive and were off medications within 1 mo. Two children developed recurrence 1 mo post-operatively, one with an initial unilateral pheochromocytoma and one with paraganglionoma. At the last follow up, 10 out of 12(83 %) were disease free while two with recurrence are still awaiting surgery.

Conclusions

Surgical resection of pheochromocytoma is effective treatment to achieve cure and prolong survival. Cortex preservation should be done in bilateral disease as risk of recurrence in such cases seems to be of lesser significance as compared to the morbidity and mortality of adrenal insufficiency and consequent lifelong hormone replacement.  相似文献   
73.
Aim: To evaluate and compare the shear bond strength of resilient liners with heat cure denture base resins in the presence or absence of saliva. Materials and methods: Two commercially available heat polymerized acrylics and three commercially available denture liners were immersed in artificial saliva for 7 days and 14 days, respectively. A total of 180 (Acralyn-H, No.90 and Lucitone - 199, No.90) specimens were prepared. Total of 90 overlapping joint specimens were prepared, 45 of them using Acralyn H (AGroup) and rest 45 using Lucitone-199 (L-Group). The specimens were tested for flexural strength with a 3-point bending test on an Instron universal testing machine. The results were analyzed with a one-way analysis of variance (ANOVA). Results: The mean difference in shear bond strength (SBS) at different time intervals was found to be statistically significant (p < 0.001). Lucitone-199 recorded a significantly higher mean SBS compared to Acralyn H (p < 0.001). Further, significant differences between GC and Densply, GC and Aswin liners, and between Dentsply and Aswin were noted (p < 0.001). Difference between baseline and 7 days time interval, as well as, between baseline and 14 days time interval with respect to the mean SBS of these materials were significant (p < 0.001). Also, the mean difference in SBS between 7 days time interval and 14 days time interval was statistically significant (p < 0.001). Among the three different liners, GC yielded a higher mean SBS compared to Aswin and Dentsply at all the three time intervals. The mean SBS recorded in Dentsply and Aswin was almost same at 14 days time interval, but at baseline and 7 days, it was higher in Aswin compared to Dentsply. Conclusion: Lucitone-199 recorded a higher mean SBS compared to Acralyn H. As the time interval increases, the mean SBS recorded in both the denture base materials decrease. Among the three different liners, GC yields a higher mean SBS compared to Aswin and Dentsply at all the three time intervals. Clinical significance: The most common reason for failures of resilient linings in removable dentures is the separation of these linings from the denture base. Therefore, poor adhesive bond properties are one of the serious defects of the material in clinical practice. Keywords: Heat cure resins, Methyl methacrylacte, Polymethylmethacrylate, Percentage of cohesive, Failure, Shear bond strength. How to cite this article: Rao CS, Reddy SS, Prasad GM, Reddy KS, Rao NV, Naik MS. A Study to Evaluate and Compare the Shear Bond Strength of Resilient Liners with Heat Cure Denture Base Resins, with and without the Effect of Saliva: An in vitro Study. J Contemp Dent Pract 2012;13(3):394-400. Source of support: Nil Conflict of interest: None declared.  相似文献   
74.
Arrangement of artificial teeth in a bilaterally symmetrical fashion with proper inclinations of teeth had been a challenging task for beginners. A variety of tools and guiding equipment have been developed to help students to learn teeth arrangement. Unfortunately, those tools were either costly or unsuitable for use with mean value articulators. This article attempts to introduce a simplified clinometer which can be attached to mean value articulator and can be used as a guide to arrange teeth in a bilaterally symmetrical manner by the undergraduates in both clinical and preclinical set-up. CLINICAL SIGNIFICANCE: Training of the future dentists in sound esthetic principles in a preclinical environment, using this device, will increase the final clinical efficacy of their work. AIM: The aim of this article is to provide a simple but effective device to undergraduate students to help them learn teeth arrangement easily and systematically.  相似文献   
75.
Aim: The aim of this study was to assess the effect of different orthodontic treatment needs on the OHQoL of adolescents. Materials and methods: 200 subjects (100 males and 100 females), 11 to 15 years of age were recruited for the study. OHQoL was assessed with the short form of the oral health impact profile (OHIP-14), and malocclusion severity was assessed with the index of orthodontic treatment need (IOTN). The Chi-square test was used to analyse the qualitative data. The level of significance was 0.05. Results: The more severe the malocclusion the worse was the impact on the OHQoL. Orthodontic treatment need had almost similar impact on the daily activities of both males and females. Pronunciation and taste was not significantly affected by the need for orthodontic treatment in either males or females. The proportions of orthodontic patients who found it uncomfortable to eat any food and had to interrupt their meals were significantly correlated with orthodontic treatment needs in both males and females. Conclusion: Orthodontic treatment need had an impact on OHQoL of adolescents with no significant difference between males and females. Clinical significance: Orthodontists should be aware of the impact caused by malocclusion and orthodontic treatment on the quality of life of the patients and should provide regular positive reinforcements to them. Keywords: Oral health-related qualtiy of life, Orthodontic treatment need, Malocclusion. How to cite this article: Manjith CM, Karnam SK, Manglam S, Praveen MN, Mathur A. Oral Health-Related Quality of Life (OHQoL) among Adolescents Seeking Orthodontic Treatment. J Contemp Dent Pract 2012;13(3):294-298. Source of support: Nil Conflict of interest: None declared.  相似文献   
76.
Transmigration of an impacted tooth through the symphyseal suture is a rare and special developmental anomaly of unknown etiology that is unique to the mandibular canine. Maxillary canine transmigration is even rarer. Transmigrated canines are particularly significant due to the aesthetic and functional importance. A maxillary lateral incisor crossing the mid-palatal suture has never been reported in the literature. The aim of this report is to present the first case of simultaneous transmigration of a lateral incisor and canine in the maxilla. The paper also reports four unusual cases of unilateral canine transmigration in the maxilla and mandible and successful eruption of one of the transmigrated mandibular canines following orthodontic traction. Etiology of transmigration and its clinical considerations are also discussed.  相似文献   
77.
78.
Circumferential stent fracture is extremely uncommon, and in rare cases, it can cause stent thrombosis. Recognizing stent fracture can be difficult on conventional fluoroscopy because of poor stent radiopacity. We found that StentBoost image acquisition yields improved visibility of stent struts, enabling the identification of stent fracture and the precise positioning of new stents over previously stented segments.We report the case of a 50-year-old man who presented with acute myocardial infarction and subacute stent thrombosis a week after percutaneous transluminal coronary angioplasty and placement of a bare-metal stent. The new lesion was crossed with a guidewire, but multiple attempts to advance a balloon catheter were unsuccessful. Live StentBoost image acquisition revealed circumferential stent fracture into 2 separate sections, with abnormal angulation between the proximal and distal portions of the stent. With StentBoost guidance, the wire and balloon catheter were both easily manipulated to cross the lesion, and angioplasty and restenting were completed with good results.StentBoost can be a useful adjunctive tool for the cardiac interventionist during complex percutaneous transluminal coronary angioplasty, and it was invaluable in this challenging situation. We discuss stent fracture and the benefits of using StentBoost in such situations.  相似文献   
79.
Lipoarabinomannan (LAM) is a critical virulence factor in the pathogenesis of Mycobacterium tuberculosis, the causative agent of tuberculosis. LAM is secreted in urine and serum from infected patients and is being studied as a potential diagnostic indicator for the disease. Herein, we present a novel ultra-sensitive and specific detection strategy for monomeric LAM based on its amphiphilic nature and consequent interaction with supported lipid bilayers. Our strategy involves the capture of LAM on waveguides functionalized with membrane mimetic architectures, followed by detection with a fluorescently labeled polyclonal antibody. This approach offers ultra-sensitive detection of lipoarabinomannan (10?fM, within 15?min) and may be extended to other amphiphilic markers. We also show that chemical deacylation of LAM completely abrogates its association with the supported lipid bilayers. The loss of signal using the waveguide assay for deacylated LAM, as well as atomic force microscopy (AFM) images that show no change in height upon addition of deacylated LAM support this hypothesis. Mass spectrometry of chemically deacylated LAM indicates the presence of LAM-specific carbohydrate chains, which maintain antigenicity in immunoassays. Further, we have developed the first three-dimensional structural model of mannose-capped LAM that provides insights into the orientation of LAM on supported lipid bilayers.  相似文献   
80.
PurposeAurora kinase B (AURKB) plays a pivotal role in the regulation of mitosis and is gaining prominence as a therapeutic target in cancers; however, the role of AURKB in retinoblastoma (RB) has not been studied. The purpose of this study was to determine if AURKB plays a role in RB, how its expression is regulated, and whether it could be specifically targeted.MethodsThe protein expression of AURKB was determined using immunohistochemistry in human RB patient specimens and immunoblotting in cell lines. Pharmacological inhibition and shRNA-mediated knockdown were used to understand the role of AURKB in cell viability, apoptosis, and cell cycle distribution. Cell viability in response to AURKB inhibition was also assessed in enucleated RB specimens. Immunoblotting was employed to determine the protein levels of phospho-histone H3, p53, p21, and MYCN. Chromatin immunoprecipitation–qPCR was performed to verify the binding of MYCN on the promoter region of AURKB.ResultsThe expression of AURKB was found to be markedly elevated in human RB tissues, and the overexpression significantly correlated with optic nerve and anterior chamber invasion. Targeting AURKB with small-molecule inhibitors and shRNAs resulted in reduced cell survival and increased apoptosis and cell cycle arrest at the G2/M phase. More importantly, primary RB specimens showed decreased cell viability in response to pharmacological AURKB inhibition. Additional studies have demonstrated that the MYCN oncogene regulates the expression of AURKB in RB.ConclusionsAURKB is overexpressed in RB, and targeting it could serve as a novel therapeutic strategy to restrict tumor cell growth.  相似文献   
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