Comparison of Clinicopathologic Factors in 122 Patients with Resected Pancreatic and Ileal Neuroendocrine Tumors from a Single Institution

Background  

Recent population-based studies have demonstrated significant differences in outcome between patients with pancreatic and ileal neuroendocrine tumors. The objective of this study was to examine the clinicopathologic differences between ileal and pancreatic neuroendocrine tumors following resection.     

A prospective 3-year study of fixed bridges linking Astra Tech ST implants to natural teeth

BACKGROUND: Connecting teeth and osseointegrated implants in fixed reconstructions is not generally recommended because of differences in their response to loading. AIM: The aim of the present study was to assess the clinical and radiographic performance of the teeth and implants used to support three unit fixed bridges subjected to normal functional loads. SUBJECTS AND METHODS: Nineteen subjects (10 males, nine females, age range 27-65 years) with an edentulous posterior free end saddle in either maxilla or mandible (Kennedy Class 2), and opposing natural teeth or a tooth-supported fixed bridge were treated and completed the 3-year trial. An Astra Tech ST implant (length: 9 mm (n=2), 11 mm (n=9) or 13 mm (n=8); diameter: 4.5 mm) was placed immediately distal to the last tooth or leaving a single premolar sized space. The distal tooth received a gold coping and the implant was restored with a customised Prepable abutment (Astra Tech Profile BiAbutment: diameter 5.5 or 7 mm). A fixed bridge was placed linking the gold coping and implant abutment either with the pontic as a distal cantilever (n=6, length 7-8 mm) or as a fixed-fixed design (n=13, length 6-12 mm). Standardised radiographs and clinical records were taken at delivery of the prosthesis (baseline BL) and annually. RESULTS: Plaque scores at implant sites increased between BL and subsequent years (P<0.02). Statistically significant increases in probing depth were observed at both abutment teeth and implants between baseline and subsequent years (P<0.001). Marginal bone levels (mm) at the implant and tooth were stable between BL, 1-, 2- and 3-year examinations (implant: BL 0.65+/-0.42, 1 year 0.63+/-0.47, 2 years 0.88+/-0.55, 3 years 0.78+/-0.64; tooth: BL 2.29+/-0.82, 1 year 2.41+/-0.8, 2 years 2.38+/-1.02, 3 years 2.68+/-0.86). No signs of the intrusion of the abutment teeth were detected. One case of abutment screw loosening occurred. Eight bridges required re-cementation with a permanent cement in place of the temporary cement. There were eight subjects presenting with fractures/chips to the composite component of the bridges. CONCLUSION: The 3-year results demonstrate fully functional successful restorations with no evidence of tooth intrusion and with stable bone levels at both teeth and implants.     

Coxiella burnetii Infection Increases Transferrin Receptors on J774A.1 Cells

Inoculation with viable, but not inactivated, Coxiella burnetii resulted in the increased expression of transferrin receptors (TfR) in the murine macrophage-like cell line J774A.1. This upregulation was evident in immunoblots as early as 6 h postinfection, with TfR levels continuing to increase through the first 24 h of infection. Fluorescent labeling revealed that TfR upregulation occurred throughout infected monolayers, eliminating the possibility that it reflected a response by a minor subset of host cells. In addition, TfR trafficking did not appear to be affected by C. burnetii infection. Consistent with the increase in TfRs, inoculation with viable C. burnetii resulted in a 2.5-fold increase in total cellular iron by 12 h postinoculation. Our further findings that the chelation of intracellular iron arrests C. burnetii replication and that C. burnetii metabolic activities in vitro are affected by iron concentration suggest that TfR upregulation is a salient factor in C. burnetii infection, and we speculate that it may represent a significant virulence mechanism.     

Simultaneous demonstration of phenylethanolamine N-methyltransferase immunofluorescent and catecholamine fluorescent nerve cell bodies in the rat medulla oblongata

The distribution of phenylethanolamine N-methlytransferase-immunoreactive nerve cell bodies was investigated in the rat medulla using an antiserum to bovine phenylethanolamine N-methyltransferase raised in rabbits. A procedure that combines immunohistochemistry and catecholamine fluorescence histochemistry was developed with a formaldehyde/glutaraldehyde mixture as a fixative. Three groups of immunoreactive nerve cell bodies were found in the medulla: a ventrolateral group, C1, a dorsal group, C2, in the nucleus of the tractus solitarius and a smaller medial group of cells, C3, scattered in the medial longitudinal fasciculus. Most of the phenylethanolamine N-methyltransferase positive nerve cells did not show catecholamine fluorescence and did not correspond to the catecholamine cell groups A1 and A2. Both groups C1 and C2 of immunoreactive nerve cells extended further rostrally than A1 and A2. Group C3 has not previously been described as a distinct group of catecholamine fluorescent nerve cell bodies.Inhibition of phenylethanolamineN-methyltransferase and monoamine oxidase results in the appearance of catecholamine fluorescence in the immunoreactive cell bodies suggesting that they usually store adrenaline which reacts poorly with the formaldehyde/glutaraldehyde mixture or other aldehydes which induce catecholamine fluorescence and it is for this reason that they are not normally identified in maps of catecholamine fluorescent cells.     

Mu-specific properties of lambda phages containing both ends of Mu depend on the relative orientation of Mu end DNA fragments

To facilitate the study of bacteriophage Mu transposition we have constructed plaque-forming λ phages containing all the Mu genes and sites known to be required for normal levels of Mu transposition (i.e., Mu genes A and B and the two Mu DNA ends). These phages were made by in vitro recombination of EcoR1 DNA restriction fragments from two donor λ phages, each containing an EcoR1 fragment carrying one end of Mu. Theoretically the resulting phages with both ends of Mu could possess the two Mu-containing fragments in different orientations with respect to each other and to the lambda DNA, producing eight classes of hybrid phages. The results of agarose gel electrophoresis of DNA fragments produced by HindIII digestion of phage DNA allowed most phages to be assigned to one of the eight expected classes. Electron microscopic analysis of DNA heteroduplexes was used to confirm these classifications. Intact representatives were recovered for only six of the eight expected classes. Those phages containing the two Mu ends in closest proximity to one another were not recovered intact; however, deleted derivatives of this type of phage were found. The relative orientation of Mu-containing DNA fragments in phages from the six recovered classes was critical in determining the Mu-specific reactions which they carried out. All intact λ-Mu clones complemented Mu phages defective in genes A and B, but only those phages from the two classes with the Mu-containing fragments in their normal relative orientation complemented A-defective phage at a high level. Phages in the same two classes were also unique in their ability to carry out a second Mu-specific reaction which resulted in inhibition of their own growth.