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Background: Endovascular aneurysm repair is a minimally-invasive method for the treatment of abdominal aortic aneurysms. For aneurysms that involve the visceral arteries, a custom-made stent graft with fenestrations for the branch arteries is required. The purpose of the current study is to evaluate the structural impact of misaligned fenestrations with respect to luminal patency and proximal aortic neck apposition in an in vitro model., Methods: A custom apparatus was used to evaluate seven Anaconda and three Zenith fenestrated stent grafts. All stent grafts were evaluated at 10° increments of stent/fenestration misalignment up to 80°. Images were captured at each interval and the luminal cross-sectional area and wall apposition were measured., Results: The Anaconda stent graft, which has an unsupported main body, demonstrated a linear reduction in luminal patency at increasing angles of misalignment (P < 0.0001). Stent/fenestration misalignments of 20° and 80° resulted in decreases in mean luminal patency of 14% and 54% respectively. The Zenith stent graft demonstrated a similar decrease in luminal patency, starting at misalignments of ≥40° (P < 0.0001). However, with stent/fenestration misalignments of ≥30°, apposition between the Zenith stent graft and the simulated aortic neck was compromised suggesting the creation of a type Ia endoleak., Conclusions: Both the Anaconda and Zenith devices behave adversely at extreme angles of misalignment with luminal narrowing in the Anaconda device and loss of wall apposition in the Zenith device; however, both stent grafts appear to be equivalent at low angles of misalignment., (Copyright © 2016 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.)

Purpose: This study compared the quantity of preweighed, packaged die stone use to bulk die stone use by dental students., Materials and Methods: Starting in September 1994, all the bulk die stone was removed from the dental clinic, and only preweighed packages of die stone (Silky-Rock, Whip Mix) were available to students. At the end of August 1995 and August 1997, the amount of preweighed die stone used by the students was determined and compared with the amount of bulk die stone (DieKeen, Modern Materials) used during the period of September 1993 to August 1994., Results: Between September 1994 and August 1997, the students used 42% less per annum of the preweighed, packaged die stone than the previous annual use of bulk die stone. The laboratories were much cleaner when the preweighed packages were used, and fewer cleaning staff were required. The environment was also cleaner for the laboratory staff, who used to fill the bulk containers with gypsum products., Conclusions: Students used 42% less die stone per annum when using the preweighed packages.

We determined the prevalence of other sexually transmitted diseases (STDs) in 56 women infected with the human immunodeficiency virus (HIV) and compared the usefulness of this prevalence to that of standard risk assessment alone in identifying HIV-infected women. Of the 56 women studied, 54 were infected with HIV. These women received instruction as to the modes of transmission and were then placed in standard risk groups based on their own assessments. A history of previous or current STD was obtained and followed by appropriate testing. We found that combining standard risk assessment with a current or previous STD enabled us to identify a greater percentage of women who are infected with HIV.

Epstein-Barr virus (EBV) infection of the EBV-negative Burkitt lymphoma (BL) cell line BL2 has been studied in vitro, to assess the efficiency of stable infection and the state of the viral genome in these cells. Expression of the EBV nuclear antigen complex (EBNA 1-6) was detected by 24 h post-infection, but expression of the latent membrane protein (LMP) and of the B cell activation antigen CD23 were delayed until 8 days post-infection, and were then only detectable in a subpopulation of EBNA-positive cells. Separation of cells into CD23-positive and -negative fractions 8 days after infection showed that the CD23-positive cells expressed EBNA 1-6 and LMP and contained viral episomes, whereas the CD23-negative cells were EBNA 1-6 positive, LMP negative and had very low levels of episomal viral genome. Cloning of the CD23-positive and -negative populations showed that EBV infection in the majority of clones was lost, with only 29 out of the 164 investigated still EBNA positive after 6 months of culture. Stable infection correlated with expression of EBNA 1-6, LMP, CD23 and the presence of viral episomes. One clone stably expressed EBNA 1-6 and LMP in the absence of detectable linear or episomal viral genome; this clone was assumed to have a viral genome integrated into the cellular chromosomes. Thus integration of the viral genome following in vitro infection of BL2 cells is a rare event.

Epstein-Barr virus (EBV) infection of B lymphocytes in vitro gives rise to immortalized lymphoblastoid cell lines. Previous reports have shown that chronic lymphocytic leukaemia (CLL) cells, although infectable by EBV, are resistant to immortalization (1-4), although a small number of CLL cell lines have been reported (5-7). In the present study we have analysed early events occurring after EBV infection in 16 CLL samples. Out of 16 samples, 15 could be infected by the virus and expressed the full EB viral nuclear antigen (EBNA) complex but only one out of 16 expressed the latent membrane protein (LMP). The five CLLs in which we could investigate the presence of viral episomes showed circularized EBV by 16 hours after infection. The sequence of EBNA expression and genome circularization mirrored that seen in normal B cells, although genome amplification was not detected. The only CLL sample which expressed LMP after EBV infection was induced to proliferate for 2-3 weeks, but no cell line was established. Immortalized cell lines were obtained from three out of 16 samples tested, but all were polyclonal for light chain expression and had arisen from the CD5-negative, normal B-cell population. Thus the inability of EBV to induce proliferation of most CLL cells correlated with the absence of LMP expression which is invariably expressed during immortalization of normal B cells. This novel type of restricted gene expression could be compatible with evasion of host immune responses and consequent long-term survival of the cell in vivo.

This study was performed to determine the prevalence, serotypes and antibiotic susceptibility patterns of penicillin-resistant Streptococcus pneumoniae in children younger than 3 years of age in day-care centers in Houston, TX. Nasopharyngeal cultures were obtained on two occasions, in March and May, 1989, from 140 children in 4 day-care centers. All penicillin-resistant S. pneumoniae organisms isolated in this study had minimum inhibitory concentrations to penicillin of between 0.1 and 0.5 microgram/ml and were thus intermediately resistant. No highly resistant S. pneumoniae (minimum inhibitory concentration > or = 1.0 microgram/ml) was isolated in this study. Nasal carriage of S. pneumoniae occurred in 39% of children; carriage of intermediately resistant S. pneumoniae occurred in 4% of children. Of the 39% of children who carried S. pneumoniae, 11% carried intermediately resistant strains. In one day-care center with a prior history of intermediately resistant S. pneumoniae (Center 1), the prevalence of intermediate penicillin resistance was significantly (P = 0.047) higher than in the other three centers. Among children surveyed twice 15% of Center 1 children carried an intermediately penicillin-resistant strain at least once, whereas in the other centers 3% of children carried an intermediately resistant strain at least once. Sixty-two percent of intermediately penicillin-resistant strains were resistant to multiple antibiotics and all were serotype 14. Intermediately penicillin-resistant S. pneumoniae isolates were prevalent among young children in day-care centers in Houston and may persist in some day-care centers and become endemic.

The dimensions of 120 maxillary first premolar all-ceramic tooth preparation designs were measured and analyzed to determine relationships between design features and recorded differences in the strengths of restorations fabricated for each preparation design. To assess clinical feasibility, the remaining dentin thickness of each preparation design was measured. A total occlusal convergence angle of 10 degrees provided the best combination of restoration strength and remaining dentin thickness. Five degrees produced the weakest restorations, and 15 degrees and 20 degrees required greater tooth reduction and pulp proximity. Stronger restorations were noted when the shoulder finish line had a sharp axiogingival line angle, possessed minimal cervical inclination, and was located as close as possible to the same occlusocervical level on all four axial surfaces.

Six maxillary first premolar tooth preparation designs for all-ceramic restorations were tested for their effect on the strength of Dicor crowns. Ten crowns were fabricated for each preparation design, and the breaking strengths were measured. Three finish line designs (1.2-mm shoulder with sharp axiogingival line angle, 1.2-mm chamfer, and 0.8-mm chamfer) and two total occlusal convergence angles (5 degrees and 15 degrees) were tested. All preparations possessed 2.0 mm of occlusal reduction. The average breaking strengths of the 10 Dicor crowns were compared to those of 10 metal ceramic control restorations. The three groups of restorations fabricated for preparations with 5 degrees of occlusal convergence were significantly weaker than those made for preparations with 15 degrees of convergence. The metal ceramic restorations were significantly stronger (247.45 kg) than the strongest Dicor crowns (56.2 kg).

Six maxillary first premolar all-ceramic tooth preparation designs were tested for their effect on the strength of Dicor crowns. Ten crowns were fabricated for each preparation design, and their breaking strengths were measured. Three finish line designs (1.2-mm shoulder with sharp axiogingival line angle, 1.2-mm shoulder with rounded axiogingival line angle, and 0.8-mm chamfer) and two total occlusal convergence angles (10 degrees and 20 degrees) were tested. All preparations possessed 2.0 mm of occlusal reduction. The average breaking strengths of the 10 Dicor crowns were compared to that of 10 metal ceramic control restorations. The tooth preparation with a 1.2-mm shoulder finish line, sharp axiogingival line angle, and 10 degrees of total occlusal convergence produced the strongest Dicor crowns (88.6 kg). The weakest restorations were observed when a 0.8-mm chamfer finish line (66.8 kg) was used. The metal ceramic restorations were significantly stronger (247.45 kg) than the strongest Dicor crowns (88.6 kg).