Spindle cell melanoma coexisting with chronic lymphocytic leukemia/small lymphocytic lymphoma: a rare collision tumor in multiple sites

A strong association has been reported between chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL) and malignant melanoma (MM). In rare cases of MM, lymphoid malignancies may be detected incidentally during sentinel lymph node biopsies. In this case, we found a unique collision of MM and CLL infiltration in the skin. An 88-year-old male patient presented with a mass on the nasal root. Histopathological examination of the skin biopsy specimen revealed a deeply infiltrative, atypical spindle cell proliferation in the background of a collagenous stroma. Accompanying this lesion, there were foci of monotonous lymphoid cell populations involving skin appendages. In the immunohistochemical studies, the spindle cells were diffusely positive for S100, and focally positive for Melan-A and HMB45; the lymphoid cells were positive for CD20, CD5, and Bcl-2 and negative for CD3, Bcl-6, CD10, and Cyclin D1. Histopathological and immunohistochemical findings were consistent with diagnoses of spindle cell melanoma and CLL. Interestingly, these two tumors together in their same morphological appearance were confirmed in a subsequent liver biopsy. Active skin surveillance of patients with CLL may be important to detect MM at an early stage that correlates with a better prognosis.     

Mandibular symphyseal distraction osteogenesis: review of three techniques

Mandibular symphyseal distraction osteogenesis (MSDO) is an alternative strategy to correct mandibular transverse deficiencies and dental crowding. Only a limited number of practitioners have reported their clinical experience and potential complications of this procedure to widen the mandible in a large case series. This study involved retrospective analysis of 40 patients who underwent mandibular symphyseal distraction osteogenesis. Three different types of distractor were used to widen the mandible: tooth-borne in 21 patients, bone-borne in 5 patients and hybrid (both bone and tooth-borne) in 14 patients. The distraction amount ranged from 7 to 11 mm (mean 7.31 mm). While 39 patients underwent successful mandibular symphyseal distraction, there was one failure. Most of the complications were experienced in bone-borne distractors, such as breakage of the distractor rod, gingival recession, secondary infection and ptosis of the chin. In the light of these findings, it is suggested that a lingually placed tooth-borne hyrax appliance is more suitable and reliable than the other distraction devices. Further larger studies are needed in order to better evaluate the effectiveness of bone-borne or hybrid devices.     

Time-related wettability characteristic of acrylic resin surfaces treated by glow discharge

STATEMENT OF PROBLEM: Adhesion and cohesion have important roles in denture retention, and attempts have been made to improve the wettability of the acrylic resin material by surface treatments. PURPOSE: This study examined the initial and subsequent wettability of an acrylic resin denture base material treated under air or argon plasma atmosphere before and after exposure to air or distilled water. MATERIAL AND METHODS: Acrylic resin specimens were treated with plasma under air or argon atmosphere and were either exposed to air or distilled water for up to 60 days. Wettability characteristics of the acrylic resin specimens were determined by contact-angle measurements after 2 hours and after 60 days. Surface composition of the specimens also was analyzed with x-ray photoelectron spectroscopic (XPS) measurements. RESULTS: Statistically significant difference was found between control and each of the plasma treatment groups (P <.05). Although the storage condition and storage period caused statistically significant difference on contact angle values (P <.05), atmosphere type did not have any effect on the results (P >.05). XPS spectra of the plasma-treated specimens differed from control specimens only in the O1s region with a narrower and more intense peak that could be assigned to -COH groups. During 60 days of exposure, the O/C atomic ratios decreased within the first 2 weeks but settled to 0.40 and 0. 32 up to 60 days compared with 0.26 for untreated control specimens. CONCLUSION: Glow discharge plasma altered the surfaces of the acrylic resin and increased thc wettability as shown both by XPS and contact-angle measurements, and plasma treatment seemed to offer a durable (at least up to 60 days) wettability.     

Comparison of ultrasonography with magnetic resonance imaging in the diagnosis of temporomandibular joint internal derangements: a preliminary investigation

OBJECTIVE: This study aimed to compare ultrasonography (US) with magnetic resonance imaging (MRI) with respect to the diagnosis of temporomandibular joint (TMJ) internal derangements. STUDY DESIGN: The study group consisted of 23 patients with a chief complaint of TMJ discomfort who were tentatively diagnosed by means of head-neck examination as having TMJ internal derangements and a control group of 9 volunteers who had no sign of TMJ internal derangements. All the patients were then examined by means of MRI and US. RESULTS: The results showed perfect agreement between MRI and US in the diagnosis of TMJ internal derangements (kappa = 1.000; P =.0001). CONCLUSION: MRI and US can be used to define the disk and its position, as well as the presence of TMJ internal derangements.     

Mid-term result of ceramic bearings in total hip arthroplasty

Purpose

The purpose of this study was to evaluate our clinical experience with ceramic-on-ceramic cementless total hip arthroplasty (THA) and complications after an average follow-up of more than eight years.

Methods

From January 2001 to December 2008, 540 THA with ceramic-on-ceramic bearings were performed in 448 patients (92 bilateral, 54 of which were operated simultaneously) with a mean age 49.9 years (range 18–84) by a senior surgeon. Pre-operative aetiological reasons were developmental dysplasia of the hip (DDH) in 205 hips, degenerative arthritis in 157 hips, avascular necrosis in 51 hips, rheumatoid diseases in 40 hips, posttraumatic arthritis in 40 hips, other reasons in 25 hips and revision surgery in 22 hips. Patients were evaluated with Harris hip score (HSS), and radiological findings of acetabular and femoral component loosening or osteolysis with ceramic bearing related complications like squeaking, liner and head fractures were recorded.

Result

The average duration of follow-up time was 8.2 years (range, five to 13.2). The main Harris hip score increased from 42.4 points preoperatively to 94.9 points at the time of last follow-up. We had one fracture of the ceramic head, 11 clicking and four squeaking; one of them was revised because of terrible squeaking due to acetabular liner fracture, the other three were seldom audible from the outside and followed conservatively. We did not observed loosening or osteolysis due to ceramic bearings at the time of the final follow-up.

Conclusion

Our study has demonstrated that ceramic-on-ceramic bearings can be used safely in different etiological problems. Incidences of noisy hips are becoming less frequent.     

Profiling of β-Lactam Selectivity for Penicillin-Binding Proteins in Streptococcus pneumoniae D39

Selective fluorescent β-lactam chemical probes enable the visualization of the transpeptidase activity of penicillin-binding proteins (PBPs) at different stages of bacterial cell division. To facilitate the development of new fluorescent probes for PBP imaging, we evaluated 20 commercially available β-lactams for selective PBP inhibition in an unencapsulated derivative of the D39 strain of Streptococcus pneumoniae. Live cells were treated with β-lactam antibiotics at different concentrations and subsequently incubated with Bocillin FL (Boc-FL; fluorescent penicillin) to saturate uninhibited PBPs. Fluorophore-labeled PBPs were visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and fluorescence scanning. Among 20 compounds tested, carbapenems (doripenem and meropenem) were coselective for PBP1a, PBP2x, and PBP3, while six of the nine penicillin compounds were coselective for PBP2x and PBP3. In contrast, the seven cephalosporin compounds tested display variability in their PBP-binding profiles. Three cephalosporin compounds (cefoxitin, cephalexin, and cefsulodin) and the monobactam aztreonam exhibited selectivity for PBP3, while only cefuroxime (a cephalosporin) was selective for PBP2x. Treatment of S. pneumoniae cultures with a sublethal concentration of cefuroxime that inhibited 60% of PBP2x activity and less than 20% of the activity of other PBPs resulted in formation of elongated cells. In contrast, treatment of S. pneumoniae cultures with concentrations of aztreonam and cefoxitin that inhibited up to 70% of PBP3 activity and less than 30% of other PBPs resulted in no discernible morphological changes. Additionally, correlation of the MIC and IC₅₀s for each PBP, with the exception of faropenem, amdinocillin (mecillinam), and 6-APA, suggests that pneumococcal growth inhibition is primarily due to the inhibition of PBP2x.