Zinc oxide is an environmentally friendly and readily synthesized semiconductor with many industrial applications. ZnO powders were prepared by alkali precipitation using different [Zn(acetate)(amine)] compounds to alter the particle size and aspect ratio. Slow precipitations from 95 °C solutions produced micron-scale particles with morphologies of hexagonal plates, rods, and needles, depending on the precursor used.
View Article and Find Full Text PDFIn this study, we have fabricated nanofuses from thin-film, arc-deposited carbon for use in permanent data storage. Thin-film carbon fuses have fewer fabrication barriers and retain the required resistivity and structural stability to act as a data-storage medium. Carbon thin films were characterized for their electrical, microstructural, and chemical bonding properties.
View Article and Find Full Text PDFA significant genetic cline has previously been identified along the Chilean coast in the barnacle Notochthamalus scabrosus. Samples from the previous study, spanning 800 km, were not able to show whether the southern lineage ultimately goes to fixation at higher latitudes. In addition to expanding the geographic sampling of this species, locations that were sampled approximately four to five generations ago were resampled for this study, enabling a temporal comparison of the location and strength of the observed cline.
View Article and Find Full Text PDFThe development of crops genetically engineered for pathogen resistance has raised concerns that crop-to-wild gene flow could release wild or weedy relatives from regulation by the pathogens targeted by the transgenes that confer resistance. Investigation of these risks has also raised questions about the impact of gene flow from conventional crops into wild plant populations. Viruses in natural plant populations can play important roles in plant fecundity and competitive interactions.
View Article and Find Full Text PDFThe Hematopoietic- and neurologic-expressed sequence 1 (Hn1) gene encodes a small protein that is highly conserved among species. Hn1 expression is upregulated in regenerating neural tissues, including the axotomized adult rodent facial motor nerve and dedifferentiating retinal pigment epithelial cells of the Japanese newt. It is also expressed in numerous tissues during embryonic development as well as in regions of the adult brain that exhibit high plasticity.
View Article and Find Full Text PDFThe hematopoietic- and neurologic-expressed sequence 1 (Hn1) gene encodes a highly conserved protein that is expressed in developing and regenerating tissues. In this study, Hn1 expression was evaluated in human and murine malignant gliomas. Hn1 mRNA and protein were detected in the murine GL261 glioma cell line and in GL261 brain tumors in vivo.
View Article and Find Full Text PDFA method is presented for quickly identifying contaminants in a material. Fourier transform infrared (FT-IR) spectra are collected for anomalous and normal material using a method that gives highly reproducible absolute intensity, such as attenuated total reflection (ATR) spectroscopy of liquids or solids that contact the crystal perfectly. The difference spectrum is calculated as the point-by-point subtraction of absorbance values without the use of a variable subtraction factor, giving a spectrum with positive and negative spectral features.
View Article and Find Full Text PDFBackground: The United States Preventive Services Task Force found that effective interventions for extending breastfeeding duration are generally begun during the prenatal period, provide ongoing support for patients and combine information with face-to-face guidance. A 2001 literature review had similar findings but also found that employing a lactation consultant in the clinical setting may increase breastfeeding duration rates. Thus, a program was developed at a family practice office that employed a lactation consultant and followed the American Academy of Pediatrics' "Ten Steps to Support Parents' Choice to Breastfeed Their Baby.
View Article and Find Full Text PDFObjective: To design and implement a simulated patient-case assessment using a mannequin for critical care pharmacotherapeutic education of doctor of pharmacy students and to evaluate student satisfaction with the simulation.
Design: During the second year of the doctor of pharmacy program, all students were required to complete Introduction to Critical Care. This course consisted of didactic education, written patient-case sessions, and an interactive patient simulation session.
Veterinarians in the United States and abroad are faced with growing public concern for the welfare of animals, particularly those in production. To prepare veterinarians to exert the leadership expected by the public and industry, steps should be taken to provide instruction in animal welfare at veterinary colleges. The ultimate goal is to offer courses in animal welfare in a consistent manner on a global scale, utilizing existing expertise in an efficient and cost-effective manner.
View Article and Find Full Text PDFAm J Health Syst Pharm
September 2003
Curr Treat Options Cardiovasc Med
October 2003
Advances in immunosuppressive therapy have contributed to the improved long-term survival of pediatric heart transplant recipients over the past two decades. The introduction of cyclosporine in the early 1980s (the first oral agent to selectively target T-lymphocyte pathways) led to a dramatic reduction in acute rejection rates and improved graft and patient survival. A combination of cyclosporine, azathioprine, and corticosteroids ("triple therapy") became the standard of care for pediatric and adult heart transplantation.
View Article and Find Full Text PDFOverexpression of the epidermal growth factor receptor (EGFR) and its association with the tyrosine kinase, c-Src, is correlated with increased cellular proliferation and tumorigenesis. Previous studies have shown that EGFR and c-Src co-overexpression and association leads to the c-Src-mediated phosphorylation of tyrosine 845 of the EGFR and that mutation of Tyr(845) ablates epidermal growth factor (EGF)-induced DNA synthesis. Here, we investigate the contribution of the signal transducers and activators of transcription (STAT5b) in the signaling pathways regulated by EGFR and c-Src overexpression in human breast tumor cell lines as well as in a mouse fibroblast model (C3H10T1/2).
View Article and Find Full Text PDFWe have investigated and compared GH and epidermal growth factor (EGF) signaling in primary human skin fibroblasts from normal subjects and subjects with GH-binding protein-positive Laron syndrome (LS). In normal human fibroblasts, GH and EGF activate the tyrosine phosphorylation of signal transducer and activator of transcription (STAT)1 and STAT5b; in LS fibroblasts, EGF does, but GH does not. GH also activates the tyrosine phosphorylation of Janus kinase (JAK)2 in normal, but not LS, fibroblasts.
View Article and Find Full Text PDFExposure of LLC-PK1 epithelial cell cultures to phorbol ester tumor promoters causes immediate translocation of protein kinase C-alpha (PKC-alpha) from cytosolic to membrane-associated compartments. With a very similar time course, a dramatic and sustained increase in tight junctional (paracellular) permeability occurs. This increased permeability extends not only to salts and sugars but macromolecules as well.
View Article and Find Full Text PDFThe role of PKC-alpha in altered epithelial barrier permeability following the activation of PKC by TPA (12-O-tetradecanoyl phorbol 13-acetate) and bryostatin 1 in LLC-PK1 cells was investigated in this study. Like TPA, bryostatin 1 binds to and activates PKC but unlike TPA, it is not a tumor promoter. TPA at 10(-7) M induced a sustained 95% decrease in transepithelial electrical resistance (R(t)) across LLC-PK1 epithelial cell sheets, while 10(-7) M bryostatin 1 caused only a 30% decrease in R(t), which spontaneously reversed after 5 h.
View Article and Find Full Text PDFBackground: Tumor necrosis factor-alpha (TNF) has been implicated in the development of postoperative morbidity after cardiopulmonary bypass for myocardial revascularization. Despite their postulated roles as modulators of TNF bioavailability, soluble TNF receptors have not been characterized in patients undergoing this procedure and is the focus of this study.
Methods: Soluble tumor necrosis factor receptor I (sTNFRI) and TNF were measured by immunoassay in plasma samples collected from 36 patients at events before, during, and after cardiopulmonary bypass.
Anim Behav
September 2000
In a previous experiment, we showed that domestic pigs, Sus scrofa, unlike many other species, performed accurately in a spatial memory task, where visits to a previously baited food trough were rewarded (win-stay). We investigated whether pigs have a predisposition for this strategy, by comparing their performance in a radial arm maze under either win-stay (N=10) or win-shift (N=10) reward contingencies. Contrary to our earlier results, only one of the animals in the win-stay condition was able to reach the imposed criterion level of accuracy.
View Article and Find Full Text PDFEpithelial tissues act as barriers between two fluid compartments, and the epithelial barrier function is provided by the epithelial cells and the tight junctions (TJs) that connect them. We have shown previously that chronic treatment of a cultured epithelial monolayer with phorbol ester tumor promoters induces an increase in transepithelial paracellular permeability and produces tumor-like polyps, suggesting an association between TJ permeability and tumor formation. In this study, we analyzed the association between TJ permeability and formation of tumors in vivo.
View Article and Find Full Text PDFHCT116 human colon carcinoma xenografts were grown in nude mice. Frozen sections of control and irradiated tumors were stained and analysed for the distribution and extent of hypoxia and apoptosis. Tissue oxygen partial pressure was measured by immunohistochemical staining of hypoxia-dependent metabolites of the 2-nitroimidazole EF5.
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