Sonodynamic therapy (SDT) is an emerging stimulus-responsive approach for the targeted treatment of solid tumours. However, its ability to generate stimulus-responsive cytotoxic reactive oxygen species (ROS), is compromised by tumour hypoxia. Here we describe a robust means of preparing a pH-sensitive polymethacrylate-coated CaO nanoparticle that is capable of transiently alleviating tumour hypoxia.
View Article and Find Full Text PDFPassive leg movement (PLM)-induced hyperemia is used to assess the function of the vascular endothelium. This study sought to determine the impact of movement speed and range of motion (ROM) on the hyperemic response to PLM and determine if the currently recommended protocol of moving the leg through a 90° ROM at 180°/sec provides a peak hyperemic response to PLM. 11 healthy adults underwent multiple bouts of PLM, in which either movement speed (60-240°/sec) or ROM (30-120° knee flexion) were varied.
View Article and Find Full Text PDFFour populations of the large freshwater ostracod, (Baird, 1862), were discovered on the Caribbean island of Montserrat. These are the first records of the species on Montserrat and extend its known distribution approximately 113 km northwest and 63 km southeast of the closest known populations on Îles des Saintes (Guadeloupe) and Nevis, respectively. We provide the first DNA barcode for , a 686 bp fragment of the COI gene which may be used for future comparative studies of this widely distributed species.
View Article and Find Full Text PDFThe presence of the freshwater polychaete, Namanereis hummelincki (Augener), on Montserrat is documented for the first time. Although collected in the sediment of a freshwater stream, this subterranean species most likely lives in groundwater aquifers. A mitochondrial cytochrome c oxidase subunit I (COI) sequence obtained from this material supports assignment to the genus Namanereis Chamberlin, and morphological analysis supports identification as N.
View Article and Find Full Text PDFGravit Space Biol Bull
June 2000
Some of the most extreme environments where animals survive are associated with active vents and seeps in the deep sea. In addition to the extreme pressure, low temperatures, and lack of light that characterize the deep sea in general, a variety of other factors that are hostile to most animals prevail in these environments. Hydrothermal vent regions show extremes in temperature, areas of very low oxygen, and the presence of toxic hydrogen sulfide and heavy metals.
View Article and Find Full Text PDFNaturwissenschaften
April 2000
During a research cruise in July 1997 in the Gulf of Mexico we discovered a gas hydrate approximately 1 m thick and over 2 m in diameter which had recently breached the sea floor at a depth of 540 m. The hydrate surface visible from the submarine was considerably greater than that of any other reported hydrate. Two distinct color bands of hydrate were present in the same mound, and the entire exposed surface of the hydrate was infested (2500 individuals/m2) with 2 to 4 cm-long worms, since described as a new species, Hesiocaeca methanicola, in the polychaete family Hesionidae (Desbruyères and Toulmond 1998).
View Article and Find Full Text PDFTransforming growth factor beta (TGF-beta) inhibits proliferation of keratinocytes cultured from normal anogenital epithelia; however, human papillomavirus (HPV)-immortalized cell lines often exhibit increased resistance. Present results demonstrate that TGF-beta 1 (1-10 pM) stimulates growth of multiple HPV-immortalized cell lines when cultures are maintained under conditions promoting squamous differentiation (MCDB153-LB medium with 1.0 mM calcium and without epidermal growth factor and bovine pituitary extract).
View Article and Find Full Text PDFWhen trying to assess the implications of recent deep shifts in the philosophy of science for the broader arena of medicine, the theme that most readily comes to mind is underdetermination. In scientific research one always hopes for determination: that the world should determine the observations we make of it; that evidence should determine the theories we adopt; that the practice of science should determine results independent of the sort of society in which that practice takes place. In this essay, doubts cast on each of these ideas by recent work in philosophy of science will be discussed and the consequences for philosophy of medicine will be indicated.
View Article and Find Full Text PDFInfection with multiple sexually transmitted agents has been associated with inflammation of the cervix and an increased risk of cervical cancer in women infected with human papillomaviruses (HPVs). Two proinflammatory cytokines, interleukin 1 alpha (IL-1 alpha) and tumor necrosis factor alpha (TNF-alpha), inhibited proliferation of normal epithelial cells cultured from human cervix. In contrast, both cytokines significantly stimulated proliferation of cervical cell lines (5 of 7) immortalized by transfection with HPV-16 or -18 DNAs or lines derived from cervical carcinomas (7 of 11).
View Article and Find Full Text PDFChanges in the extent of phosphorylation of the 25 kDa subunit of eIF-4F occur during several major biological events including mitosis and heat shock in mammalian cells and shortly after fertilization of sea urchin (Lytechinus pictus) eggs. In vitro phosphorylation studies using highly purified protein kinases demonstrated that the 220 kDa subunit of eIF-4F was phosphorylated by cAMP dependent protein kinase, protein kinase C and probably to a lesser extent by cGMP dependent protein kinase. In addition, eIF-4A was readily phosphorylated by cAMP and cGMP dependent protein kinases whereas p48 of eIF-4F was not.
View Article and Find Full Text PDFThe 25 kDa mRNA cap binding protein can be purified in a partially phosphorylated state and the extent of its phosphorylation appears to be regulated during heat shock and mitosis in mammalian cells. We demonstrated that a nonabundant serine protein kinase activity exists in rabbit reticulocytes that phosphorylates the 25 kDa cap binding protein in both the free (eIF-4E) and complexed (eIF-4F) state. This kinase was not inhibited by the cAMP-dependent protein kinase inhibitory peptide IAAGRTGRRNAIHDILVAA, did not phosphorylate S6 ribosomal protein, did not phosphorylate p220 of eIF-4F as protein kinase C does and no other substrates for this kinase were apparent in reticulocyte ribosomal salt wash.
View Article and Find Full Text PDFThe most ambitious simulation approach to computer-aided diagnosis is probably that of CADUCEUS. A review of its strategies may be expected to reveal some, at least, of the strengths and weaknesses of this approach, as well as to turn up problems of interest to the philosopher of science concerned with the logical structures implicit in the process of diagnostic judgment.
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