I Brent Heath

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In rapidly growing hyphae of Saprolegnia ferax, all nuclei contain arrays of kinetochore microtubules, which suggests that the nuclei are all in various phases of mitosis, with no apparent interphase. In prophase nuclei, kinetochore microtubules form a single, hemispherical array adjacent to the centrioles. This array separates into two similar arrays after(More)
The plasma membrane of tip-growing hyphae of the oomycete Saprolegnia ferax contains stretch-activated (SA) Ca(2+)-permeable and Ca(2+)-activated K+ ion channels. Patch clamp measurements on protoplasts derived from specific regions of hyphae demonstrated that SA channels were most abundant in the tip. Gadolinium (Gd3+) inhibited SA channel activity and(More)
The comparative behavioral and neurochemical activities of the muscarinic cholinergic antagonists scopolamine, trihexyphenidyl and pirenzepine, and the nicotinic cholinergic antagonist mecamylamine were evaluated in rats. The three muscarinic antagonists, but not the nicotinic antagonist, impaired memory performance in a spatial alternation task. The(More)
172 Light and Electron Microscope Studies on Jirovecia involuta sp. A Complementary Experimental Study of Cell Division in the Dinoflagellate Prorocentrum micans Hrabyeia xerkophora n. gen. n. sp., a New Microsporidian with Tailed Spores from the Oligochaete Nais christinae Kasparzak, 1973 Location of rDNA in the Heteromeric Macronucleus of Chilodo-nella(More)
Growing hyphae of the ascomycete fungus Neurospora crassa contained a tip-high gradient of cytoplasmic Ca2+, which was absent in non-growing hyphae and was insensitive to Gd3+ in the medium. Patch clamp recordings in the cell-attached mode, from the plasma membrane of these hyphae, showed two types of channel activities; spontaneous and stretch activated.(More)
Aspects of the ultrastructure of mitotic nuclei of the fungus Uromyces phaseoli var. vignae are described from both intercellular hyphae in the cowpea host and infection structures induced to differentiate in vitro. The interphase nucleus-associated organelle (NAO) consists of two trilamellar acircular disks connceted by an osmiophilic bar. The intranuclear(More)
Serial sections of mitotic spindles of the marine cryptophycean alga, Cryptomonas, were analysed to determine what types of microtubules they contained and which of these microtubules came close enough to each other (50 nm or less) for the commonly described crossbridging to be possible. Interpolar microtubules were rare (less than or equal to 1%) but from(More)
Staphylococcus aureus bacteraemia (SAB) is commonly complicated by metastatic infection or relapse after treatment. Objectives. The study aim was to determine the role of bacterial, host, and management factors in development of complicated SAB. Methods. A prospectively-conducted observational study gathered data on predisposition, management and outcome of(More)
Direct visual observation and time lapse films of in vitro differentiating infection structures of the cowpea rust fungus Uromyces phaseoli var. vignae revealed three categories of movement: a) general movement of cytoplasm, plus organelles, into the developing portions of the fungus during which the nuclei, in particular, maintained their characteristic(More)
Creating and maintaining cell polarity are complex processes that are not fully understood. Fungal hyphal tip growth is a highly polarized and dynamic process involving both F-actin and microtubules (MTs), but the behaviour and roles of the latter are unclear. To address this issue, MT dynamics and subunit distribution were analysed in a strain of(More)