Amalgam repair: evaluation of bond strength and microleakage

This study evaluated the tensile bond strength of "repaired" amalgams and compared the degree of microleakage. Amalgam (Cavex avalloy) was condensed into plastic tubes (3 mm in diameter, 10 mm in height) to the half-length. After storage in water at 37 degrees C for two days, the remaining parts of tubes were filled with amalgam (A), cavity varnish (CV)+A, Liner Bond 2V (LB2V)+A, 3M Opal Luting Cement (3MOLC)+A, Panavia F(PF)+A, Metabond(MB)+A, Fuji BondLC(FB)+A, HytacOSB(HOSB)+Hytac Aplitip (H), Liner Bond2V+Clearfil AP-X(CAP). The bond strengths for 15 samples of each restoration group were determined. For the microleakage study, MOD cavities of 90 extracted human premolars were used. The distal half of cavities were filled with amalgam. After storage in water at 37 degrees C for two days, the mesial half of the cavities were filled to simulate a clinical repair. The "repair" was placed using the procedures applied in the bond strength study. The teeth were stained with basic fuchsine (0.5%), sectioned and evaluated for dye penetration. In both parts of study, the data were analyzed by ANOVA and Duncan's multiple range tests. Bond strength values (MPa) were: A+PF+A 3.84+/-1.08, A+LB2V+A 3.15+/-0.97, A+LB2V+CAP 3.05+/-0.53, A+MB+A 2.86+/-0.88, A+HOSB+H 2.58+/-0.51, A+3MOLC+A 2.11+/-0.75, A+FB+A 0.68+/-0.59. The repaired A+A and A+CV+A groups were separated before testing. The A+PF+A group showed the highest bond strength (p<0.05). Microleakage in the cervical margins of repaired restorations was lower in the amalgam groups than microleakage in the resin composite and compomer groups. PF, MB, 3MOLC and FB performed better at the amalgam "repair" interface. The A+LB2V+A group showed no microleakage at both the occlusal and gingival test regions.     

A case of Castleman's disease with "downhill" varices in the absence of superior vena cava obstruction

Downhill esophageal varices", classically defined as those that develop in the upper region of the esophagus, are less common than the "uphill" type, which is usually produced by portal hypertension. Various causes of downhill varices have been reported, but mediastinal tumor is the most common responsible lesion. Castleman's disease, or angiofollicular lymph node hyperplasia, is a rare pathological process of unknown etiology that usually develops in the mediastinum. We report the case of a 60-year-old woman whose large esophageal varices were detected incidentally. The cause was a mediastinal mass which was diagnosed as Castleman's disease on histopathological examination of a surgical specimen. This patient's varices most likely formed as a result of copious blood drainage from the tumor into the esophageal veins. Evidence for this was the lack of the classic downhill pattern, the absence of superior vena cava obstruction, and the fact that the varices resolved after the tumor was removed. It is our opinion that this type of varices should be renamed, and we suggest that "overflow varices" would be an appropriate term.     

Signet-ring cell change versus signet-ring cell carcinoma: a comparative analysis

Signet-ring cell change (SCC) is a nonneoplastic condition that morphologically simulates signet-ring cell carcinoma (SRCA). The few case reports on SCC have focused on morphologic characteristics in distinguishing benign from malignant. In biopsy specimens, however, SCC can be easily confused with SRCA, which often demonstrates innocuous cytologic features. The object of this study is twofold: 1) to report 14 additional cases of SCC, comparing their morphologic and phenotypic features with that of SRCA; and 2) to evaluate the incidence of SCC in pseudomembranous colitis. Paraffin sections of biopsy or resection specimens containing focal or extensive SCC and 5 cases of colonic SRCA were stained with hematoxylin and eosin, periodic-acid Schiff stain with and without diastase digestion, and by standard ABC immunoperoxidase procedure using antibodies to E-cadherin, p53, and Ki-67. Both cells in SCC and SRCA were strongly positive for neutral mucins. Cells in SCC were strongly positive for E-cadherin and negative for p53 and Ki-67. In contrast, cells in SRCA were strongly positive for p53, exhibited high proliferation, and demonstrated absent or weak positivity for E-cadherin. Although SCC is not well recognized in pseudomembranous colitis, the incidence is fairly high: 14 of 50 (28%) cases showed variable numbers of signet-ring cells. Extensive SCC, although rare, can occur in different clinical conditions and can be easily mistaken for SRCA. When in doubt, routine immunohistochemical stains such as p53, Ki-67, and E-cadherin can help to differentiate SCC from SRCA.     

Efficacy of tramadol versus meperidine for pain relief and safe recovery after adenotonsillectomy

BACKGROUND AND OBJECTIVE: Adequate relief of pain after tonsillectomy is a common problem. We compared meperidine and tramadol when given at induction of anaesthesia with respect to their effects on postoperative pain relief and emergence characteristics after adenotonsillectomy in children. METHODS: Fifty children aged 4-7 yr undergoing tonsillectomy were randomly assigned to receive either tramadol 1 mg kg(-1) (n = 25) or meperidine 1 mg kg(-1) (n = 25) before commencement of the surgical procedure. Anaesthesia was induced with propofol (with cis-atracurium for muscle relaxation) and maintained with sevoflurane in oxygen and nitrous oxide. Postoperative pain was scored by a blinded observer using a facial pain scale in the recovery room at 0 (at arrival of the patient in the postoperative care unit) and at 10, 20 and 45 min thereafter. Agitation scores were also assessed by the same observer at 0 min. Heart rate and mean arterial pressure were recorded at regular intervals. The time to recovery to spontaneous respiration and the incidence of postoperative nausea and vomiting were noted. RESULTS: Facial pain scale scores were increased in the tramadol group at 0, 10 and 20 min (P < 0.05). No difference was observed in scores at the 45th min postoperation. Agitation scores were higher in the tramadol group than in the meperidine group. No statistical difference was found between the two groups. Heart rates and mean arterial pressures were similar in both groups. The time to recovery to spontaneous respiration was delayed with meperidine compared with tramadol (P < 0.05). The incidence of nausea and vomiting was not statistically different between groups. CONCLUSIONS: Meperidine was more effective for pain relief and provides better emergence characteristics than tramadol after tonsillectomy in children.     

Morphometry of the anterior third ventricle region as a guide for the subfrontal (translaminaterminalis) approach

The anterior third ventricle region acquires clinical significance in benign and malignant tumors and cyst formations, of which craniopharyngiomas and gliomas are the most common. The subfrontal approach is one of the most preferred approaches for removing these tumors. In this study, the microsurgical anatomy of 81 Turkish, adult cadaveric hemispheres was examined to provide morphometric data of the region. These measurements from the anterior third ventricle region serve as a guide for neurosurgeons during surgical approach for removing anterior third ventricle tumors.     

The ameliorating effect of melatonin on protamine sulfate induced bladder injury and its relationship to interstitial cystitis

PURPOSE: The pineal hormone melatonin was recently shown to have free radical scavenging ability and it reduces lipid peroxidation. In this morphological study we investigated the effects of melatonin on protamine sulfate (Sigma Chemical Co., St. Louis, Missouri) induced bladder injury. MATERIALS AND METHODS: Albino Wistar female rats were catheterized and intravesically infused with phosphate buffered solution (control group) or protamine sulfate (bladder injury group) dissolved in phosphate buffered solution. In the protamine sulfate plus melatonin group after protamine sulfate instillation melatonin was injected intraperitoneally. Bladder morphology was investigated by light and electron microscopy. Tissue samples were also obtained to determine bladder malondialdehyde levels. RESULTS: In the bladder injury group ulcerated areas, an irregular glycosaminoglycan layer, increased number of mast cells, vacuole formation, dilated perinuclear cistern, formation of pleomorphic and uniform microvilli, and dilated urothelial intercellular spaces were observed. In the bladder injury plus melatonin group a relatively normal urothelial topography, glycosaminoglycan layer and decreased number of mucosal mast cells, some dilatation between intercellular areas, less uniform microvilli and in most areas regular tight junctions were observed. CONCLUSIONS: Increased malondialdehyde levels as a result of protamine sulfate induction lead us to propose that free radicals may have a critical role in this injury. The significant decrease in malondialdehyde levels in the protamine sulfate plus melatonin group was in accordance with morphological findings. Thus, melatonin appears to exert a urothelial protective activity in a bladder injury model.     

Cyclosporine A toxicity in association with reduced renal mass

The long-term effect of cyclosporine A (CsA) in male Wistar rats with reduced renal mass was studied. The aim of the study was to highlight the relationship of CsA effect on rats, simulating patients with two functioning kidneys (eg, heart, liver transplant recipients) and one kidney (renal transplant recipients). The Wistar rats were subjected to unilateral nephrectomy (Unx, n = 14) and to 5/6 nephrectomy (STnx, n = 14). Half of these rats and half of the sham operated ones (control, n = 13) were administered CsA (10 mg/kg/d) for 28 days IP. The serum creatinine (S(CR)), total protein (S(P)), and urine protein (U(P)) values as well as the whole blood CsA levels were determined on the 28th day of the study. The remnant kidneys were evaluated by image analyses and semiquantitative methods after sacrifice on the 28th day.In the three non-CsA-treated groups (Unx, STnx, and control) S(CR) was significantly higher in STnx rats than in Unx rats (P =.011). Percent of renal scarring (PRS) was significantly higher in Unx (P =.02) and in STnx rats (P =.017), compared with the control group. Among CsA-treated three groups S(CR) was significantly higher in STnx rats compared with Unx (P =.017). In addition, segmental sclerosis rate (SSR) was higher in STnx rats, compared with the control group (P =.008), whereas S(P) was higher in the control group (P =.005). When CsA-treated groups were compared with non-CsA-treated ones, U(P) of the Unx rats not receiving CsA were significantly higher than the Unx rats receiving CsA (P =.026). Also, U(P) was higher in non-CsA-treated groups (P =.014), whereas S(CR) (P =.001), S(P) (P =.001), and PRS (P =.001) were higher in CsA-treated rats.In conclusion, we suggest that preserved renal mass is not enough to prevent CsA toxicity and that CsA should be administered to patients with both kidneys (eg, heart, pancreas recipients) as carefully as to patients with one functioning kidney (renal transplant recipients).     

GJB2 gene mutations causing familial hereditary deafness in Turkey

Mutations in Connexin 26 (Cx26) play an important role in autosomal non-syndromic hereditary hearing loss. In this study, our objective was to find out the significance of Cx26 mutations in Turkish families who had hereditary deafness. Fourteen families who had at least two prelingually deaf children per family were included in the study. One affected child from each of the 14 families was selected for single-stranded conformational polymorphism SSCP analysis. Three PCR reactions were used for each subject to amplify the entire Cx26 coding region with overlap. PCR products were sequenced on an Applied Biosystems (ABI) model 3700 automated sequencer. Six of the 14 representative family members (42.9%) demonstrated shifts on SSCP and were subsequently sequenced for Exons 1 and 2 of GJB2 and were tested for the 432 kb upstream deletion. No mutations were found in Exon 1 and no 432 kb deletions were noted. Three different GJB2 mutations were found in Exon 2 of the probands, which were 35delG, 299-300delAT, and 487G > A (M163V). GJB2 mutations were detected in 21.4% of the families. Two patients were homozygous for 35delG and 299-300delAT mutations, and were given a diagnosis of DFNB1 deafness (14.3%). Two different polymorphisms, 457G > A (V153I) and 380G > AG (R127H) were also found. In conclusion, although GJB2 mutations were detected in 21.4% of the families tested, only 14.3% of subject representatives were homozygous and therefore deafness caused by Cx26 mutation segregated with DFNB1. Thus, contribution of GJB2 mutations appears less significant in familial deafness. This necessitates further assessment for the other known gene regions as well as a search for new genetic factors in familial type of genetic deafness.