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Solvent extraction of organic wood preservative, creosote, yielded three classes of creosote contituents namely polycyclic aromatic hydrocarbons (PAHs), phenolics and heterocyclics, that inhibit the fluoranthene-degrading activity of Sphingomonas paucimobilis strain EPA505. The integration of a pretreatment step prior to inoculation of strain EPA505 could help increase the effectiveness of strain EPA505 to degrade fluoranthene.

This proceeding presents experiments demonstrating that BioLPTM, Biological Laser Printing, can be used to rapidly and accurately print individual cells as well as patterns of cells in three dimensions. Human osteosarcoma cells were deposited into a biopolymer matrix, and after twenty-four hours of incubation, the printed cells remained viable and had multiplied. Multiple layers of human osteosarcoma cells were transferred into a MatrigelTM substrate, producing a three-dimensional cellular construct. Live/dead assays were performed, demonstrating that greater than 95% of the cells were viable after the being printed into the biopolymer. The ability to selectively print individual cells has potential benefits for cell selection studies and genomics and proteomics research. In addition, this technique could enable layers of tissue scaffolding to be seeded with cells at exceedingly high precision and resolution. [ABSTRACT FROM AUTHOR]

Presents a study on adult patients with nephrotic syndrome and diffuse epithelial cell disease. Clinical assessment of the patients; Groups in which the patients were histologically separated after the assessment; Features of patients with focal glomerulosclerosis.

Presents a study of Wilson's disease with reversible renal tubular dysfunction. Method of the study; results and discussion; Conclusion.

One of the primary requirements of cell- or tissue-based sensors is the placement of cells and cellular material at or near the sensing elements of the device. The ability to achieve precise, reproducible and rapid placement of cells is the focus of this study. We have developed a technique, biological laser printing or BioLP, which satisfies these requirements and has advantages over current technologies. BioLP is capable of rapidly depositing patterns of active biomolecules and living cells onto a variety of material surfaces. Unlike ink jet or manual spotting techniques, this process delivers small volume (nl to fl) aliquots of biomaterials without the use of an orifice, thus eliminating potential clogging issues and enabling diverse classes of biomaterials to be deposited. This report describes the use of this laser-based printing method to transfer genetically-modified bacteria capable of responding to various chemical stressors onto agar-coated slides and into microtiter plates. The BioLP technology enables smaller spot sizes, increased resolution, and improved reproducibility compared to related technologies.

We have generated mesoscopic patterns of viable Escherichia coli on Si(1 1 1), glass, and nutrient agar plates by using a novel laser-based transfer process termed matrix assisted pulsed laser evaporation direct write (MAPLE DW). We observe no alterations to the E. coli induced by the laser-material interaction or the shear forces during the transfer. Transferred E. coli patterns were observed by optical and electron microscopes, and cell viability was shown through green fluorescent protein (GFP) expression and cell culturing experiments. The transfer mechanism for our approach appears remarkably gentle and suggests that active biomaterials such as proteins, DNA and antibodies could be serially deposited adjacent to viable cells. Furthermore, this technique is a direct write technology and therefore does not involve the use of masks, etching, or other lithographic tools.

We explored the use of the reversible cross-linking reagent dimethyl 3,3-dithiobispropionimidate (DTBP) in combination with CO treatment as an approach to stabilizing erythrocyte structure and function. Erythrocytes were cross-linked with different concentrations of DTBP for different times. DTBP increased erythrocyte osmotic stability, blocked lysolecithin-induced echinocytosis, and decreased erythrocyte deformability in a concentration- and time-dependent manner. Reversal of the cross-linking with the reducing agent dithioerythritol (DTE) restored osmotic fragility and response to lysolecithin as well as deformability. Complete reversal, however, is a function of the DTBP concentration and the time of cross-linking. The effects of cross-linking with 5 mM DTBP for 1 h were completely reversible after treatment with 10 mM DTE for 20 min. Longer incubation times or higher concentrations of DTBP resulted in partial reversal by DTE of the effects produced by DTBP. Cross-linking and reversal only slightly reduced the ATP content. The hemoglobin contained in the cross-linked and reversed cells could still undergo reversible oxygenation and deoxygenation. Erythrocytes were pretreated with CO, cross-linked with 5 mM DTBP for 1 or 3 h, loaded with a solution containing 500 mM glucose for 24 h, and freeze-dried in a medium containing 15% (w/v) albumin. Rehydration followed in distilled water. Complete recovery, measured as the percentage of free hemoglobin, was achieved for cells cross-linked with 5 mM DTBP for 3 h and freeze-dried to a final water content of 10-15%. Non-cross-linked cells lysed 100% on rehydration in distilled water. No methemoglobin (MetHb) formation as a result of freeze-drying was detected in CO-treated cells. In non-CO-treated cells 20% of the Hb was converted to MetHb., (Copyright 2000 Academic Press.)

Acute renal insufficiency is a common problem, yet one that is frequently reversible with proper diagnosis and treatment. Although it has been argued that a renal biopsy is not needed for diagnosis in most cases of acute renal failure in the elderly, other studies have shown frequent disagreements between clinical and renal biopsy diagnoses in such cases. To investigate the causes of acute renal insufficiency in patients aged at least 60 years who underwent a renal biopsy and possible correlations between biopsy findings and renal survival, we first identified all native renal biopsy specimens from patients aged 60 years or older processed at The University of Chicago Medical Center (Chicago, IL) from 1991 through 1998 and reviewed the clinical records to determine the indication for the biopsy. We then reviewed again the records of those patients who underwent biopsy because of acute renal insufficiency, recorded the primary renal biopsy diagnosis in each of these cases, and obtained follow-up information for patients who underwent biopsy before July 1996. During the study period, 1,065 of 4,264 biopsy specimens (25.0%) received were obtained from patients aged 60 years or older, and acute renal insufficiency was the indication for biopsy in 259 of these patients (24.3%). The most frequent primary diagnoses on these latter biopsy specimens were pauci-immune crescentic glomerulonephritis (GN) with or without arteritis, 31.2% of biopsy specimens; acute interstitial nephritis, 18.6%; acute tubular necrosis (ATN) with nephrotic syndrome, 7.5%; atheroemboli, 7.1%; ATN alone, 6.7%; light chain cast nephropathy (LCCN), 5.9%; postinfectious GN, 5.5%; anti-glomerular basement membrane antibody nephritis, 4.0%; and immunoglobulin A (IgA) nephropathy and/or Henoch-Schönlein nephritis, 3.6%. Eight biopsy specimens (3.2%) showed only benign nephrosclerosis without an apparent cause of acute renal insufficiency, and another six specimens were inadequate. The renal biopsy diagnosis was in agreement with the prebiopsy clinical diagnosis (or differential diagnosis) in 107 of the 161 cases (67%) in which such information was provided. The distribution of diagnoses was similar in patients in the age groups of 60 to 69, 70 to 79, and 80 years or older, although younger age correlated significantly with improved renal and patient survival. The relative risk for progression to end-stage renal disease (ESRD) also increased according to diagnostic categories: LCCN (greatest risk) > GN other than pauci-immune > atheroemboli congruent with pauci-immune crescentic GN > tubulointerstitial diseases other than LCCN (the latter category including ATN with nephrotic syndrome). Development of ESRD correlated significantly with decreased patient survival. In summary, renal biopsy in patients aged 60 years or older with acute renal insufficiency uncovered the cause in greater than 90% of the cases and provided clinically useful information with respect to expectation for renal survival and potential treatment options.

Data compiled during the 1970s and early 1980s indicated that during these periods, membranous nephropathy was the most common cause of unexplained nephrotic syndrome in adults, followed in order of frequency by minimal-change nephropathy and focal segmental glomerulosclerosis (FSGS). However, we and others recently reported an increase in the incidence of FSGS over the past two decades, and the number of cases of FSGS diagnosed by renal biopsies in these centers now exceeds the number of cases of membranous nephropathy. Nonetheless, as a substantial fraction of patients with FSGS do not have the nephrotic syndrome, it remained unclear as to what extent the relative frequencies of FSGS and other glomerulopathies as causes of the nephrotic syndrome have changed over this time. To address this concern, we reviewed data from 1,000 adult native kidney biopsies performed between January 1976 and April 1979 and from 1,000 biopsies performed between January 1995 and January 1997, identified all cases with a full-blown nephrotic syndrome of unknown etiology at the time of biopsy, and compared the relative frequencies with which specific diseases were diagnosed in these latter cases between the two time intervals. The main findings of this study were that, first, during the 1976 to 1979 period, the relative frequencies of membranous (36%) and minimal-change (23%) nephropathies and of FSGS (15%) as causes of unexplained nephrotic syndrome were similar to those observed in previous studies during the 1970s and early 1980s. In contrast, from 1995 to 1997, FSGS was the most common cause of this syndrome, accounting for 35% of cases compared with 33% for membranous nephropathy. Second, during the 1995 to 1997 period, FSGS accounted for more than 50% of cases of unexplained nephrotic syndrome in black adults and for 67% of such cases in black adults younger than 45 years. Third, although the relative frequency of nephrotic syndrome due to FSGS was two to three times higher in black than in white patients during both study periods, the frequency of FSGS increased similarly among both racial groups from the earlier to the later period. Fourth, the frequency of minimal-change nephrotic syndrome decreased from the earlier to the later study period in both black and white adults. Fifth, the relative frequency of membranoproliferative glomerulonephritis as a cause of the nephrotic syndrome declined from the 1976 to 1979 period to the 1995 to 1997 period, whereas that of immunoglobulin A nephropathy appeared to increase; the latter accounted for 14% of cases of unexplained nephrotic syndrome in white adults during the latter study period. Finally, 10% of nephrotic adults older than 44 years had AL amyloid nephropathy; none of these patients had multiple myeloma or a known paraprotein at the time of renal biopsy.