An approach to an esthesioneuroblastoma of the anterior cranial fossa via the anterior wall of the hypertrophied frontal sinus]

Coenzyme Q10 was administered under placebo controlled blinded crossover conditions to six subjects suffering from type 3 3-methylglutaconic aciduria ('optic atrophy plus'), following a report of benefit. Despite attainment of high plasma levels of coenzyme Q10, no clinical benefit was observed and there was no diminution of urinary excretion of 3-methylglutaconic acid.     

Long-term survival after retransplantation of the liver

OBJECTIVE: The authors determined the long-term outcome of patients undergoing hepatic retransplantation at their institution. Donor, operative, and recipient factors impacting on outcome as well as parameters of patient resource utilization were examined. SUMMARY BACKGROUND DATA: Hepatic retransplantation provides the only available option for liver transplant recipients in whom an existing graft has failed. However, such patients are known to exhibit patient and graft survival after retransplantation that is inferior to that expected using the same organs in naiive recipients. The critical shortage of donor organs and resultant prolonged patient waiting periods before transplantation prompted the authors to evaluate the results of a liberal policy of retransplantation and to examine the factors contributing to the inferior outcome observed in retransplanted patients. METHODS: A total of 2053 liver transplants were performed at the UCLA Medical Center during a 13-year period from February 1, 1984, to October 1, 1996. A total of 356 retransplants were performed in 299 patients (retransplant rate = 17%). Multivariate regression analysis was performed to identify variables associated with survival. Additionally, a case-control comparison was performed between the last 150 retransplanted patients and 150 primarily transplanted patients who were matched for age and United Network of Organ Sharing (UNOS) status. Differences between these groups in donor, operative, and recipient variables were studied for their correlation with patient survival. Days of hospital and intensive care unit stay, and hospital charges incurred during the transplant admissions were compared for retransplanted patients and control patients. RESULTS: Survival of retransplanted patients at 1, 5, and 10 years was 62%, 47%, and 45%, respectively. This survival is significantly less than that seen in patients undergoing primary hepatic transplantation at the authors' center during the same period (83%, 74%, and 68%). A number of variables proved to have a significant impact on outcome including recipient age group, interval to retransplantation, total number of grafts, and recipient UNOS status. Recipient primary diagnosis, cause for retransplantation, and whether the patient was retransplanted before or after June 1, 1992, did not reach statistical significance as factors influencing survival. In the case-control comparison, the authors found that of the more than 25 variables studied, only preoperative ventilator status showed both a significant difference between control patients and retransplanted patients and also was a factor predictive of survival in retransplanted patients. Retransplant patients had significantly longer hospital and intensive care unit stays and accumulated total hospitalization charges more than 170% of those by control patients. CONCLUSIONS: Hepatic retransplantation, although life-saving in almost 50% of patients with a failing liver allograft, is costly and uses scarce donor organs inefficiently. The data presented define patient characteristics and preoperative variables that impact patient outcome and should assist in the rational application of retransplantation.     

An estimate by two methods of thyroid absorbed doses due to BRAVO fallout in several Northern Marshall Islands

Estimates of the thyroid absorbed doses due to fallout originating from the 1 March 1954 BRAVO thermonuclear test on Bikini Atoll have been made for several inhabited locations in the Northern Marshall Islands. Rongelap, Utirik, Rongerik and Ailinginae Atolls were also inhabited on 1 March 1954, where retrospective thyroid absorbed doses have previously been reconstructed. The current estimates are based primarily on external exposure data, which were recorded shortly after each nuclear test in the Castle Series, and secondarily on soil concentrations of 137Cs in samples collected in 1978 and 1988, along with aerial monitoring done in 1978. The external exposures and 137Cs soil concentrations were representative of the atmospheric transport and deposition patterns of the entire Castle Series tests and show that the BRAVO test was the major contributor to fallout exposure during the Castle series and other test series which were carried out in the Marshall Islands. These data have been used as surrogates for fission product radioiodines and telluriums in order to estimate the range of thyroid absorbed doses that may have occurred throughout the Marshall Islands. Dosimetry based on these two sets of estimates agreed within a factor of 4 at the locations where BRAVO was the dominant contributor to the total exposure and deposition. Both methods indicate that thyroid absorbed doses in the range of 1 Gy (100 rad) may have been incurred in some of the northern locations, whereas the doses at southern locations did not significantly exceed levels comparable to those from worldwide fallout. The results of these estimates indicate that a systematic medical survey for thyroid disease should be conducted, and that a more definitive dose reconstruction should be made for all the populated atolls and islands in the Northern Marshall Islands beyond Rongelap, Utirik, Rongerik and Ailinginae, which were significantly contaminated by BRAVO fallout.     

Characterization of cogon grass (Imperata cylindrica) pollen extract and preliminary analysis of grass group 1, 4 and 5 homologues using monoclonal antibodies to Phleum pratense

In this study, we investigated whether fluorescein isothiocyanate (FITC)-labeling of test DNA and Texas-red (TR) labeling of reference DNA in comparative genomic hybridization (CGH) experiments cause the results to differ from those obtained using the opposite combination (reverse labeling). Analysis was performed on a total of 20 DNA specimens consisting of 13 frozen bone marrow aspirates from patients with acute myeloid leukemia, and fresh peripheral blood samples from seven healthy donors. For CGH, one aliquot from each test DNA sample was labeled using nick-translation with FITC-dUTP and another with TR-dUTP. Afterwards, the FITC-dUTP and TR-dUTP-labeled test DNAs were hybridized to TR-dUTP- and FITC-dUTP-labeled normal reference DNAs, respectively. The results using the two combinations were compared with each other and with the results of G-banding karyotype analysis. Karyotype data was used to detect artifacts known to occur in some chromosome regions in CGH analysis. The control DNAs labeled with FITC or TR showed no DNA copy number changes. Regardless of the fluorochrome employed for labeling, no DNA copy number changes were detected using CGH in patients with normal karyotypes, nor in patients whose karyotype aberrations were present in less than 40% of cells. In the remaining patients, CGH revealed DNA copy number changes that coincided with the results of the G-banding analysis. Hybridization artifacts known to occur in CGH experiments affecting chromosome regions 1p33-pter, 16p, 17p, 19, and 22 were observed in 15-23% of the tumor samples labeled with FITC, but not in samples labeled with TR. In addition, other previously unreported overrepresentations affecting 7q21, 9q34, 16q, 17q, and chromosome 20 were observed at very low frequencies in up to 10% of the samples when FITC was used to label test DNA. However, when TR was used, overrepresentations were observed at 4q13-q21, 11q21-q23, 13q21-qter, and Xq21-q22, whereas 19p was underrepresented. The results demonstrate that TR-labeling confirms abnormalities detected using FITC-labeling and reduces hybridization artifacts in the known problematic regions of the human genome.     

REMOVAL OF HEAVY METALS IN ACTIVATED SLUDGE TREATMENT SYSTEMS

Studies were conducted to determine the removal of heavy metals in three normally operating activated sludge wastewater treatment plants having only moderate industrial inputs. The removals of the soluble and particulate fractions varied with primary and secondary treatment, and in one instance a tertiary sand filter.     

Structural, electrical, and optical studies on rapid thermally processed ferroelectric BaTiO3 thin films prepared by metallo-organic solution deposition technique

Polycrystalline BaTiO₃ thin films having the perovskite structure were successfully produced on platinum coated silicon, bare silicon, and fused quartz substrate by the combination of the metallo-organic solution deposition technique and post-deposition rapid thermal annealing treatment. The films exhibited good structural, electrical, and optical properties. The electrical measurements were conducted on metal-ferroelectric-metal (MFM) and metal-ferroelectric-semiconductor (MFS) capacitors. The typical measured small signal dielectric constant and dissipation factor at a frequency of 100 kHz were 255 and 0.025, respectively, and the remanent polarization and coercive field were 2.2 μC cm⁻² and 25 kV cm⁻¹, respectively. The resistivity was found to be in the range 10¹⁰–10¹² Ω·cm, up to an applied electric field of 100 kV cm⁻¹, for films annealed in the temperature range 550–700 °C. The films deposited on bare silicon substrates exhibited good film/substrate interface characteristics. The films deposited on fused quartz were highly transparent. An optical band gap of 3.5 eV and a refractive index of 2.05 (measured at 550 nm) was obtained for polycrystalline BaTiO₃ thin film on fused quartz substrate. The optical dispersion behavior of BaTiO₃ thin films was found to fit the Sellmeir dispersion formula well.     

The nature of macrophage functional heterogeneity exemplified by Fc receptors

It is known that functional activity of macrophages (Mph), adhesion and phagocytosis, depends on the local concentration of Fc receptors (Fc gamma R) on the cell surface. Fc gamma R may have a random distribution on cell membrane or form clusters of different sizes. This process depends on the local activity of microfilaments that, in its turn, reflects peculiarities of macrophage microenvironments. One may conceive that the number of opsonized erythrocytes (OE) subject to adhesion (engulfing) to separate Mph depends on the amount of active centres on the cell surface and their activity. The structures, such as Fc gamma R clusters, phagosomes and others, in whose formation numerous components of Mph (cell skeleton, microvesicles, signal receptive system and others) are involved, are arbitrarily called the structural functional units (SFU). Thus, we used two parameters: the average number of SFU per Mph in population, and the average activity of SFU instead of a generally accepted number of OE per Mph. The number of SFU per Mph can be 0, 1, 2 etc., and one SFU may bind (engulf) 0, 1, 2 etc. EA. For the assessment of the parameters, the approximation of experimental histograms by type-A Neyman's distribution was used. To verify the adequacy of the model, observations of OE adhesion and phagocytosis in different conditions were made. The results show that the parameters of the model fit well the biological processes in this system.