Evaluation of four elastomeric interocclusal recording materials

Background: The fabrication of dental prosthesis requires the transfer of interocclusal records from patient's mouth to semiadjustable articulators using different kinds of recording media. Any inaccuracy in these interocclusal records leads to occlusal errors in the final prosthesis. This study was conducted to evaluate the dimensional changes occurring in the interocclusal recording material over a given period of time and the material's resistance to compression during the cast mounting on the articulator.     

Bilateral Hematogenous Pseudomonas aeruginosa Endophthalmitis After Lung Transplantation

Pseudomonas aeruginosa commonly colonizes the airways of patients with cystic fibrosis (CF). However, the occurrence of bacteremia with metastatic infection to the eye causing endogenous endophthalmitis is very rare. In the setting of lung transplantation, the significance of P. aeruginosa bacteremia in patients with CF whose airways are colonized before transplantation is unknown. We report a case of bilateral P. aeruginosa endogenous endophthalmitis in a patient with CF after lung transplant without documented bacteremia. The patient presented with acute eye symptoms in the presence of a left atrial thrombus and the disease followed a rapidly progressive course requiring aggressive medical-surgical treatment. Typically P. aeruginosa endophthalmitis has been associated with a poor visual prognosis. However, with combined medical-surgical management this patient retained useful vision in one eye without having retinal detachment or requiring enucleation. Endogenous endophthalmitis should be considered in the differential diagnosis of ocular complaints in patients with CF after lung transplant.     

Fetal liver infusion in aplastic anaemia

Forty patients with severe aplastic anaemia received an intravenous infusion of 0.004 to 11.1 x 10(8) (median: 8 x 10(8) hematopoietic cells prepared from the fetal livers of 8-32 week old abortuses. Five patients, who died within 15 days of fetal liver infusion, are excluded from analysis. Twenty-two of the 35 evaluable patients (62%) responded favourably. Six of the 7 patients with good response were alive after 9 to 44 months (median: m = 20); one died 106 months after fetal liver infusion due to renal lithiasis. Four of the 7 with moderate response were alive after 9 to 31 months; 3 died within 16 months. Of 8 patients with minimal response, one was lost to follow-up and the others died in 3.4 to 10 months (m = 6). Median survival of responders was 15.7 months. Bone marrow cellularity became normal in 12 patients following fetal liver infusion. In seven patients, there was a relapse; 6 regained a normal bone marrow cellularity after a second or third fetal liver infusion. These data strongly suggest a role of fetal liver infusion in inducing bone marrow recovery. Of 13 non-responders, 4 were lost to follow-up and 9 died within 20 days-4.3 months (m = 1.6). Fetal liver infusion appears to be an effective therapy in patients with severe aplastic anaemia.     

Expression and characterization of recombinant soluble human CD3 molecules: presentation of antigenic epitopes defined on the native TCR-CD3 complex

The TCR-CD3 complex consists of the clonotypic disulfide-linked TCRalphabeta or TCRdeltagamma heterodimers, and the invariant CD3delta, epsilon, gamma and zeta chains. We generated plasmid constructs expressing the extracellular domains of the CD3delta, epsilon or gamma subunits fused to human IgG1 Fc. Recombinant fusion proteins consisting of individual CD3delta, epsilon or gamma subunits reacted poorly with anti-CD3 mAb including G19-4, BC3, OKT3 and 64.1. Co-expression of the CD3epsilon-Ig with either the CD3delta-Ig (CD3epsilondelta-Ig) or the CD3gamma-Ig (CD3epsilongamma-Ig) resulted in fusion proteins with much increased binding to G19-4. A brief acid treatment of the purified CD3epsilondelta-Ig fusion protein substantially improved its binding to BC3, OKT3 and 64.1. Surface plasmon resonance analysis revealed that the dissociation constants for CD3epsilondelta-Ig and anti-CD3 mAb ranged from 10(-8) to 10(-9) M. Based on these results, a single-chain (sc) construct encoding the CD3delta chain linked to the CD3epsilon chain with a flexible linker followed by human IgG1 Fc was expressed. The sc CD3deltaepsilon-scIg reacted with anti-CD3 mAb without requiring acid treatment. Moreover, anti-CD3 mAb bound CD3epsilondelta-Ig at a higher affinity than CD3epsilongamma-Ig, suggesting potential structural differences between the CD3epsilondelta and CD3epsilongamma subunits. In summary, we report the expression of soluble recombinant CD3 proteins that demonstrate structural characteristics of the native CD3 complex expressed on the T cell surface. These CD3 fusion proteins can be used to further analyze the structure of the TCR-CD3 complex, and to identify molecules that can interfere with TCR-CD3-mediated signal transduction by disrupting the interaction between CD3 and TCR subunits.     

Immunochemical evaluation of S-antigen of rabbit pineal gland

Purified S-antigen of photoreceptor cells induces experimental autoimmune uveoretinitis (EAU) and experimental autoimmune pinealitis (EAP) in laboratory animals. However, in rabbits, S-antigen induces only EAU without EAP. To evaluate this difference, the authors studied immunochemical reactivity of rabbit pineal gland with a panel of anti-S-antigen monoclonal antibodies (MAb). Rabbit pineal gland reacted with the MAbs by ELISA and immunoblot but not by immunohistochemistry. In contrast, rabbit retina like guinea pig retina, guinea pig pineal gland and bovine retina reacted with these MAbs by immunohistochemistry as well as by ELISA and immunoblot. Also, S-antigen purified from rabbit retina reacted as did bovine and guinea pig S-antigen. Therefore, S-antigen in situ in rabbit pineal gland is different from S-antigen of rabbit retina and different from S-antigen of pineal gland and retina of other species. Just as the MAbs did not react with S-antigen in rabbit pineal gland, it is possible that S-antigen activated lymphocytes may not recognize S-antigen in rabbit pineal gland and thereby not induce EAP.     

Measurement of surface alpha contamination using electret ion chambers.

Electret ion chambers are inexpensive, light-weight, commercially available, passive charge-integrating devices for accurate measurement of different radiations. Performance of electret ion chambers for surface alpha contamination measurement was evaluated. Ion chambers of two types and electrets of three thicknesses were used for the study. Calibration of the electret ion chambers was performed using reference alpha standards of different energies and radioactivities. Effects of various parameters such as chamber dimensions, electret thickness, alpha particle energy, position of alpha source from the chamber centerline, source localized or uniformly distributed, level of alpha contamination, Mylar window covering the chamber, and ambient radon and gamma radiation on the response of the electret ion chambers were determined. Suitable combinations of chambers and electrets to measure surface alpha contamination were determined.     

Epitope discovery using bacteriophage display: the minimum epitope of an anti-IRBP antibody.

The purpose of this study was to determine, using random peptide library (RPL) technologies, the minimal epitope requirements of the mouse monoclonal anti-interphotoreceptor-retinoid-binding protein antibody, H3B5. This previously characterized antibody is used as an example to examine whether RPL's offer a relatively easy and rapid route to obtaining detailed epitope mapping data.A pentadecamer random peptide library (RPL) displayed on the major coat protein (gene 8) of filamentous bacteriophage (F88-4-15) was used as a target for selection by the anti-IRBP monoclonal antibody, H3B5. Three rounds of library selection were performed, and 90 of the resultant RPL clones were examined for affinity to H3B5 by enzyme-linked immunosorbent assay (ELISA). DNA sequencing of ELISA positive clones provided sequence of the region encoding the random peptide.After three rounds of selection of the RPL, 76.7% of clones examined interacted with H3B5, 17.7% did not show significant binding and 6.6% bound to control antibody also. The essential elements of the peptide epitope were determined by sequence comparison of 24 clones to be the four amino-acid sequence (Aspartic or glutamic acid)-Proline-Arginine-(Leucine, Isoleucine or Valine). This motif [(D/E) PR (L/I/V)] is in agreement, but at greater resolution, than previous synthetic peptide studies where the motif AASEDPRL was identified. Other motifs were found which bound to H3B5 but did not share primary structure similarities (peptidomimetics). Selection from a RPL has rapidly defined the minimal requirements for the H3B5 epitope in fine detail. Such a process offers great potential for investigating antibody-antigen interactions and core sequences of an epitope, and enables the identification of motifs in other proteins which may be recognized by the antibody, providing information on possible cross-reactivity.     

Localized conjunctival extra-nodal marginal zone B cell lymphoma with presumed paraproteinic crystalline keratopathy

Crystalline corneal deposits have been well reported in individual cases of lymphoproliferative disorders associated with hyper-gammaglobulinemia, hence called ‘Crystalline Paraproteinemic Keratopathy’. This is the first report of corneal deposits in a case of localised conjunctival B-cell Lymphoma without paraproteinaemia/hyper-gammaglobulinemia, hence called ‘Presumed Paraproteinic Crystalline Keratopathy’.