Capillary Barrier Effect from Underlying Coarser Soil Layer

Infiltration tests were conducted on soil columns of silty sand over pea gravel, concrete sand over pea gravel, and silty sand over concrete sand to investigate the capillary barrier effect of an underlying coarser soil layer. Water movement across the interface occurred when the suction head at the interface reached the breakthrough head of the coarser lower soil layer, defined as the suction head at which the coarser layer first became conductive, regardless of infiltration rate or the properties of the overlying finer soil layer. Thus, the coarser lower soil layer controlled breakthrough in this study. After infiltration was terminated, the suction head near the interface increased above the breakthrough head and the barrier was restored. The breakthrough head did not change substantially after eight test cycles of breakthrough and restoration for a capillary barrier with a pea gravel as the coarser lower soil layer. The barrier formed with the concrete sand as the coarser layer permitted breakthrough at a greater suction head than did the barrier with the pea gravel, indicating that the more uniform and coarse the lower soil layer is, the more effective the capillary barrier.     

Deletion of cell division cycle 2-like 1 gene locus on 1p36 in non-Hodgkin lymphoma

Our laboratories have documented a significantly high occurrence of chromosome 1p36 rearrangements in non-Hodgkin lymphoma (NHL). The cell division cycle 2-like 1(CDC2L1) (also known as TP58 or PITSLRE) gene, a protein kinase implicated in apoptotic signaling, is located at the very distal region of chromosome 1p36 and is likely to be disrupted by structural rearrangements involving 1p36. To determine the molecular consequences of the recurrent involvement of the 1p36 region, we examined metaphases containing 1p36 abnormalities from 31 specimens derived from 26 patients for the possible deletion of CDC2L1 by fluorescence in situ hybridization (FISH) using the TP58clk-1 DNA probe. Twenty-three cases exhibited the loss of CDC2L1 from the abnormal chromosome 1. In 2 of 26 cases, the gene locus was translocated to the partner chromosome, and in four specimens, all derived from one case, CDC2L1 was not deleted. This pilot investigation suggests that 1p36 rearrangements, and consequently the loss of the CDC2L1 gene locus, is important in NHL. This work also opens avenues for further molecular studies and prognostic correlations.     

Recognition and management of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an inflammatory systemic disease that causes organ damage by the deposition of autoantibodies and complement activating immune complexes or by vascular occlusion due to procoagulant states associated with antiphospholipid antibodies. The vast majority of cases occur in women of childbearing age. SLE is diagnosed on the basis of its clinical manifestations and the demonstration of characteristic immunological phenomena, especially anti-nuclear antibodies. The prognosis in SLE has shown a distinct improvement over recent decades, the 5-year survival rate now approaching or exceeding 90%. The 15-year survival rate of 63 to 79%, on the other hand, underscores the need for further advances in diagnosis and treatment of the disease. Management of the disease includes regular monitoring of disease activity, avoidance of predisposing factors and close supervision of therapy. Drug therapy is guided by the activity and severity of the leading organ manifestations and ranges from nonsteroidal antirheumatic drugs to intensive treatment with cytotoxic agents. Corticosteroids remain irreplaceable for the control of acute flares. Antimalarials and azathioprine are important long term drugs for treating mild or moderate disease activity. Intravenous pulse cyclophosphamide is safer than other regimens and at least as effective as oral cyclophosphamide for severe lupus nephritis. It is also effective in the treatment of central nervous disease and of other organ-threatening manifestations. Recently, an intensified protocol which included cyclophosphamide induced long term treatment-free remission in 60% of patients. The toxicity of cyclophosphamide is considerable, but can be ameliorated by various measures. The value of several new immunosuppressants and other compounds remains to be determined.     

Saturation of ecosystems with toxic metals in Sudbury basin, Ontario, Canada

Mining and resource recovery activities have not been kind to ecosystems in the Sudbury basin, Ontario. The combination of logging, smelting, fires and erosion resulted in an unusual anthropogenic ecosystem of denuded barren land with lifeless lakes, or a micro-desert. Since the 1970s, however, the concerted efforts made to reduce the emissions and rehabilitate parts of the degraded ecosystem have resulted in improvements in water quality, and recoveries in phytoplankton, zooplankton, zoobenthos and fish communities but have had little impact on toxic metal concentrations in many lakes. We show that most of the catchments in the Sudbury basin have become saturated with Cu and Ni, and some with Zn and Pb. It is estimated that mobilization of metals stored in soils and glacial overburden by surface runoff, groundwater drainage and wind re-working of tailings can sustain the high concentrations of Cu and Ni in many lakes for well over 1000 years. Strategies to immobilize the pollutant metals in the watershed rather than further emission controls may be required for dealing with high levels of toxic metals in surface waters of the saturated ecosystems.     

Hepatocyte growth factor-stimulated renal tubular mitogenesis: effects on expression of c-myc, c-fos, c-met, VEGF and the VHL tumour-suppressor and related genes

Hepatocyte growth factor (HGF/SF) is a potent renal proximal tubular cell (PTEC) mitogen involved in renal development. HGF/SF is the functional ligand for the c-met proto-oncogene, and germline c-met mutations are associated with familial papillary renal cell carcinoma. Somatic von Hippel-Lindau disease tumour-suppressor gene (VHL) mutations are frequently detected in sporadic clear cell renal cell carcinomas (RCC), and germline VHL mutations are the commonest cause of familial clear cell RCC. pVHL binds to the positive regulatory components of the trimeric elongin (SIII) complex (elongins B and C) and has been observed to deregulate expression of the vascular endothelial growth factor (VEGF) gene. HGF/SF has similarly been reported to up-regulate expression of the VEGF gene in non-renal experimental systems. To investigate the mechanism of HGF/SF action in PTECs and, specifically, to examine potential interactions between the HGF/c-met and the VHL-mediated pathways for renal tubular growth control, we have isolated untransformed PTECs from normal kidneys, developed conditions for their culture in vitro and used these cells to investigate changes in mRNA levels of the VHL, elongin A, B and C, VEGF, c-myc, c-fos and c-met genes after HGF/SF exposure. Significant elevations in the mRNA levels of VEGF, c-myc, c-fos, c-met and elongins A, B and C, but not VHL, were detected after HGF/SF stimulation of human PTECs (P < 0.02), with a consistent order of peak levels observed over successive replicates (c-fos at 1 h, VEGF at 2-4 h, c-myc, at 4 h, followed by c-met and all three elongin subunits at 8 h). This study highlights the spectrum of changes in gene expression observed in PTECs after HGF/SF stimulation and has identified possible candidate mediators of the HGF/SF-induced mitogenic response. Our evidence would suggest that the changes in PTEC VEGF expression induced by HGF/SF are mediated by a VHL-independent pathway.     

Cytochrome P4502C9: an enzyme of major importance in human drug metabolism

Accumulating evidence indicates that CYP2C9 ranks amongst the most important drug metabolizing enzymes in humans. Substrates for CYP2C9 include fluoxetine, losartan, phenytoin, tolbutamide, torsemide, S-warfarin, and numerous NSAIDs. CYP2C9 activity in vivo is inducible by rifampicin. Evidence suggests that CYP2C9 substrates may also be induced variably by carbamazepine, ethanol and phenobarbitone. Apart from the mutual competitive inhibition which may occur between alternate substrates, numerous other drugs have been shown to inhibit CYP2C9 activity in vivo and/or in vitro. Clinically significant inhibition may occur with coadministration of amiodarone, fluconazole, phenylbutazone, sulphinpyrazone, sulphaphenazole and certain other sulphonamides. Polymorphisms in the coding region of the CYP2C9 gene produce variants at amino acid residues 144 (Arg144Cys) and 359 (Ile359Leu) of the CYP2C9 protein. Individuals homozygous for Leu359 have markedly diminished metabolic capacities for most CYP2C9 substrates, although the frequency of this allele is relatively low. Consistent with the modulation of enzyme activity by genetic and other factors, wide interindividual variability occurs in the elimination and/or dosage requirements of prototypic CYP2C9 substrates. Individualisation of dose is essential for those CYP2C9 substrates with a narrow therapeutic index.     

Quality assurance of psychiatric consultations in somatic hospitals

Research has shown great variety in the clinical practice of consultation-liaison psychiatry in and between different countries. This paper presents the Norwegian experiences from a European collaborative study of quality management in consultation-liaison psychiatry. We describe a dynamic model for total quality management based on regular registration of some clinical data and the subsequent feed-back on changes of these. We discuss our experiences with this model and obstacles met in everyday work. Finally we point to different ways of implementing this method on a broader base in consultation-liaison psychiatry.     

TCP fairness in. 802.11e WLANs

We investigate the use of the 8.02.11e MAC EDCF to address transport layer unfairness in WLANs. A simple solution is developed that uses the 802.11e AIFS, TXOP and CW/sub min/ parameters to ensure fairness between competing TCP uploads and downloads.     

Firearm deaths among children and youth.

Nationally, homicide and suicide are the 2nd and 3rd leading causes of death among children and youth under the age of 21. Sixteen to 19-year-olds now have the highest rate of handgun victimization among all age groups. The firearm suicide rate for White males is over 4 times higher than the rate for African American males, whereas the firearm homicide rate is over 9 times higher for African American males. Almost half of all deaths among African American male teenagers now involve firearms. Multiple steps, both short- and long-term, need to be taken to reduce firearm death rates among children and youth. Some of the possible methods to do so are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)