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The FILTER (Filtration and Irrigated cropping for Land Treatment and Effluent Reuse) technique was developed to provide a sustainable system for treatment of saline sewage effluent on naturally occurring saline and/or sodic soils. Potentially, it can also be used to ameliorate soils that are salinised by inappropriate application of saline effluent on soils with impeded drainage. The FILTER technique involves using the nutrient-rich effluent for irrigated cropping combined with removal of excess water from the rootzone through a subsurface drainage system, during wet weather and winter periods when evapotranspiration demand is low. This paper describes the changes in salinity and sodicity in FILTER plots used for land application of saline sewage effluent on a heavy clay soil with restricted drainage, at the Griffith City Council sewage works site. The field experiments consist of trials conducted on four 1-ha plots, over an 18-month period. The pre-FILTER soil chemical characteristics and their changes with FILTER operations were measured. In addition, the volumes and the chemical properties of the effluent applied and subsurface drainage water passing through the soil were monitored. These data are used to explain the salinity and sodicity changes within the FILTER soils, and their potential effects on soil stability. Management options to minimise salinity and sodicity to provide a sustainable system are suggested. wastewater treatment, SAR, ESP, soil hydraulic properties, controlled subsurface drainage.

Xerographic printing of textiles was explored. A number of fabrics were printed using commercially available and synthesized polymers as toner vehicles. The polymers were characterized using standard methods (DSC, DMA, tensile tests). The performance of the prints was evaluated using textiles-specific tests (crockfastness, flexural rigidity). It was found that the initial modulus is a reasonable predictor of the performance of the printed fabrics. However, the requirements on toner vehicles for good textile performance (low initial modulus, flexibility) contradict the requirements for production of toner powders by grinding (brittle behavior). © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2399–2407, 2001

Pancreatic endocrine tumors (PETs) continue to be challenging diagnostic and prognostic lesions in surgical pathology and clinical medicine. These neoplasms can be graded into 1 of 3 tiers, based on histologic characteristics in likeness to epithelial neuroendocrine tumors in other anatomic sites. However, grade 1 tumors are by far the most common and are the most difficult to prognosticate. The most helpful features by which to gauge the behavior of such lesions include size (3 cm or larger); mitotic activity (2 or more mitoses per 10 high-power [x400] microscopic fields); marked nuclear atypia, especially with atypical mitoticfigures; predominant tumor synthesis of gastrin, vasoactive intestinal polypeptide, somatostatin, glucagon, calcitonin, or adrenocorticotropic hormone; complete nonfunctionality of the tumor at an immunohistochemical level; or invasion of blood vessels, nerves, or adjacent organs by the neoplasm. Differential diagnosis of PETs includes lesions such as solid-pseudopapillary neoplasms, acinar carcinomas, metastatic neuroendocrine tumors, and plasmacytomas.

Dietary inadequacy of folate enhances and folate supplementation suppresses colorectal carcinogenesis in the dimethylhydrazine rat model. Folate is an essential factor for DNA methylation and the de novo biosynthesis of nucleotides, aberrations of which play important roles in mutagenesis. This study investigated whether the mutational hot spots of the Apc and p53 genes for human colorectal cancer are mutated in dimethylhydrazine-induced colorectal neoplasms and whether dietary folate can modulate mutations in these regions. Rats were fed diets containing 0, 2 (basal requirement), 8 or 40 mg folate/kg diet. Five weeks after diet initiation, dimethylhydrazine was injected weekly for 15 weeks. Mutations were determined by direct sequencing in 11 low and seven high grade dysplasias and 13 invasive adenocarcinomas. A total of six Apc mutations were found in four dysplastic and carcinomatous lesions: two in two low grade dysplasias, two in one high grade dysplasia and two in one adenocarcinoma. All mutations were single base substitutions, four of which were A:T→G:C transitions. Five of the six mutations were located upstream from the region corresponding to the human APC mutation cluster region. Dietary folate had no effect on the frequency and type of Apc mutations. No mutations were detected in exons 5-9 of the p53 gene in neoplastic lesions. These data suggest that in the dimethylhydrazine rat model of colorectal cancer, the Apc gene is mutated in early stages, albeit to a lesser degree than observed in human colorectal cancer, whereas the mutational hot spot of the p53 gene for human colorectal cancer is not commonly mutated. Although the low frequency of Apc mutations and the small number of neoplasms studied in this study might have precluded our ability to observe modulatory effects of folate, dietary folate appears to have no significant effect on Apc and p53 mutations.

The inhibition of both jack bean urease and soil urease by several heterocyclic mercaptans was investigated. The following compounds not previously tested as urease inhibitors were found to be effective inhibitors of jack bean urease: 1,3,4‐thiadiazole‐2,5‐dithiol; 5‐mercapto‐3‐phenyl‐1,3,4‐thiadiazole‐2‐thione; and 5‐amino‐1,3,4‐thiadiazole‐2‐thiol. The disulfides of the latter two compounds were found to be very potent inhibitors of jack bean urease. The results are consistent with an inhibition mechanism involving a thiol‐disulfide exchange reaction between a disulfide and one or more of the sulfhydryl groups of urease. The results also imply that inhibition of urease by the heterocyclic mercaptans was due to trace amounts of the corresponding disulfides or polysulfides in the mercaptan preparations. A number of heterocyclic mercaptans, two disulfides, and a number of known urease inhibitors were evaluated as soil urease inhibitors, and the following compounds were the most effective: 1,4‐benzoquinone ∼ hydroquinone > 2,5‐dimethyl‐1,4‐benzoquinone ∼ catechol ∼ 1,3,4‐thiadiazole‐2,5‐dithiol ∼ 2,6‐dimethyl‐1,4‐benzoquinone.

Objective: To describe the clinical, laboratory, and histopathologic features of idiopathic steatohepatitis in children. Study design: Retrospective review of all liver biopsies performed at Boston Children's Hospital, Massachusetts General Hospital, and the University of Massachusetts Medical Center from 1991 to 1994. Chart review was performed when biopsies demonstrated steatosis. Results: Eighty-two patients had biopsy-proven hepatic steatosis. Fourteen patients had fatty liver without evidence of inherited, infectious, autoimmune, endocrinologic, toxicologic, or iatrogenic causes. All 14 patients were obese, averaging 159% of ideal body weight (range, 121% to 222%). Nine patients initially had transient abdominal pain, two had hepatomegaly, and one was identified by incidental laboratory evaluation. These 12 patients had biopsies because of persistent elevations of aminotransferase levels. Two other patients without risk factors for steatosis were identified at staging laparotomy for Hodgkin lymphoma. The 10 boys and 4 girls had an average age of 13.5 years (range, 10 to 18 years). Aminotransferase elevations were modest, with aspartate aminotransferase and alanine aminotransferase values averaging 77 +/- 38 IU and 129 +/- 73 IU, respectively. All had imaging studies demonstrating diffuse fatty change. Histologic examination of biopsy specimens revealed varying degrees of steatosis with inflammation and fibrosis. Conclusion: Idiopathic steatohepatitis occurs predominantly or exclusively in obese peripubertal children. This entity represents a frequent reason for liver biopsy in this age group. The degree of steatosis, fibrosis, and inflammation does not correlate with symptoms or signs, and significant liver injury with bridging fibrosis may be present. (J PEDIATR 1995;127:700-4)

OBJECTIVES
The molecular pathogenesis of human pancreatic endocrine tumours (PETs) is largely unknown. One attractive candidate gene for involvement in pancreatic endocrine neoplasia is the retinoblastoma (Rb) tumour suppressor gene. A deletion of the Rb gene was recently described in a human insulinoma. In addition, mice harbouring a null mutation in the Rb gene bred with p53 mutant mice develop pancreatic endocrine tumours. Therefore, we sought to determine the role that allelic loss of Rb may play in a large series of human pancreatic endocrine tumours. PATIENTS AND MEASUREMENTS
46 pancreatic endocrine tumours were obtained from 41 patients. Utilizing genomic DNA isolated from the tumour samples and control normal cells, 2 highly polymorphic microsatellite loci (D13S153 and Rb 1.20) located within the Rb gene were PCR amplified and examined for loss of heterozygosity. RESULTS
2 patients were homozygous at both loci and thus uninformative. The remaining 39 had informative markers at one or both of these loci, and none of the tumours from these patients demonstrated allelic loss of Rb. CONCLUSIONS
In tumours in which Rb inactivation is pathogenetically important, somatic loss of one Rb allele commonly accompanies a point mutation or microdeletion within the other allele. Thus, the absence of demonstrable allelic loss in this large series strongly suggests that Rb gene inactivation is not frequently involved in the pathogenesis of human pancreatic endocrine tumours.

Expression of the provirus in a clonally related series of Kirsten murine sarcoma virus-transformed NIH/3T3 nonproducer cell lines was examined at both the transcriptional and translational levels. All cells expressed high levels of genome-sized viral RNA with little variation between cell lines despite differences in provirus integration site and copy number. Expression of K-ras RNA was estimated to be at least 10- to 20-fold higher than that of the mouse cellular homolog of the viral transforming gene. Levels of the virus-coded transforming protein, p21, were similarly elevated, with little variation between nonproducer cells. In two revertant cell lines containing a normal provirus and a rescuable transforming gene, no impairment in expression at either the transcriptional or translational level was found. After superinfection with Kirsten murine sarcoma virus, one revertant became more tumorigenic, whereas the other remained nontumorigenic. These results show that cell transformation by Kirsten murine sarcoma virus is invariably associated with elevated expression of the virus-coded oncogene and that one of the revertants is resistant to the action of the viral transforming gene.

Replicate field plots comprising a control, plus oil, plus oil and bacteria, plus oil and fertilizer (urea-phosphate; 27:27:0), and plus oil, bacteria, and fertilizer were monitored over a 308-day period for changes in bacterial and mold numbers. Changes in the chemical composition of the oil applied to the plots was followed by using chromatographic techniques. Application of fertilizer resulted in a stimulation of bacterial numbers and in the rate of utilization of n-alkane components of the saturate fraction. The application of oil-utilizing bacteria, however, resulted in only a slightly accelerated rate of utilization of n-alkane components of chain lengths C20 to C25. The isoprenoids, phytane and pristane, were still present in gas-liquid chromatography profiles after digestion of the n-alkane components of the saturate fraction. Those plots which received fertilizer showed an accelerated rate of recovery of native vegetation.

The effect of urbanization on the microbial content of the North Saskatchewan River was determined by following the changes in the numbers of total bacteria, total eosin methylene blue (EMB) plate count, and Escherichia colias the river flowed from its glacial source, through parklands, and out into the prairies. Changes in physical parameters such as pH, temperature, salt concentration, and the amount and nature of the suspended material were also determined to evaluate their on the microbial parameters being measured. The level of all three microbial parameters studied slowly increased as the river flowed from its glacial source out into the prairies. The major effect of small hamlets, with or without sewage treatment facilities, appears to be to supply nutrients which supports the growth of the indigenous river flora but not E. coli. In contrast, the effect of a large urban center, with a population of approximately 500,000, which utilizes primary and secondary sewage processes in disposing of sewage, is to provide the nutrients and an inoculum of E. coliwhich results in a marked increase in the numbers of all three microbial groups studied. The effect of this urban center was still discernible 300 miles downstream. The river was also monitored for the presence of Salmonellasp. Only one positive isolation was achieved during this study, and this isolate was characterized as being Salmonella alachua.

A simple technique for assaying the glutamic–aspartic transaminase activity in plant tissues making use of titrimetric measurements of the carbon dioxide yield in the ninhydrin reaction with alpha-amino acids is described. The necessary apparatus is simple and inexpensive. The success of this method is verified by comparing results with those obtained on the same or similar reaction mixtures by quantitative paper chromatography, and by the chloramine-T method. Kinetic data on enzyme preparations of corn radicle homogenates and radicle segments frozen intact have been successfully obtained. The glutamic–aspartic transaminase is very active in corn radicles, giving high initial velocities. Per cent transamination per 10 min. period varies linearly with enzyme concentration. The optimum pH for the homogenates is at 8.5.

The kinetics of transamination are complicated by the presence of two substrates whose concentrations change appreciably during the course of the reaction. The only previously published account of the kinetics of this system deviates considerably from classical theory. Equations based on premises of Michaelis and Menten have been shown, however, to accommodate the data on reaction rate in relation to substrate concentration obtained with a corn radicle enzyme preparation by a spectrophotometric method.