Search results for "actin"
showing 10 items of 1375 documents
Thiobencarb-Induced Changes in Acetylcholinesterase Activity of the Fish Anguilla anguilla
2002
Abstract European eels (Anguilla anguilla) were exposed to sublethal thiobencarb concentrations in a continuous flow-through system for 4 days. Brain, muscle, and gill acetylcholinesterase (AChE) activities were evaluated after 2, 12, 24, 48, 72, and 96 h herbicide exposure. Thiobencarb induced significant inhibitory effects on the total and specific AChE activity of A. anguilla, ranging from >30–40% inhibition in eel brain and gills to >50% inhibition in muscle tissue 2 h after the initial exposure. In a second experiment, eels were exposed to thiobencarb for 96 h and then allowed a period of recovery in pesticide-free water. Following 1 week of recovery, the AChE activity of affected eels…
Paradiplozoon iraqensis n. sp. (Monogenea: Diplozoinae) from Cyprinion macrostomum (Cyprinidae) in the Tigris River, Iraq
2015
A new species of monogenean diplozoid, Paradiplozoon iraqensis n. sp., from the gills of Cyprinion macrostomum Heckel from the Tigris River in Tikrit, Iraq is described. P. iraqensis n. sp. is distinguished from other species of the genus by the size of plicae on the fore- and hind body, the number of the branches of the intestinal caecum in fore body, intestinal caecum not extending to haptor, the size of the clamps and the morphology of the clamp sclerites, and by the length of the central hooks. Details of the shape and size of eggs, and of the reproductive system and prohaptoral region are provided. The present study raises the number of species of Paradiplozoon recorded in Iraq to 15.
The effects of treated effluents on the intensity of papillomatosis and HSP70 expression in roach.
2008
Epidermal papillomatosis in fish has been proposed as an indicator of environmental stress but experimental evidence of connection between contaminants and papillomatosis in fish is scarce. We studied changes in the intensity of epidermal papillomatosis and the expression of heat shock protein 70 (HSP70) in roach, Rutilus rutilus, exposed to treated pulp mill and municipal effluents. In male roach, the increase in papillomatosis intensity was higher in fish exposed to 15% than in fish exposed to 1.5% concentration of municipal effluent. No differences were observed in papillomatosis development in females, or in HSP70 expression. In all the experiments conducted, the increasing effect of ef…
The effect of time on physiological changes in eel Anguilla anguilla, induced by lindane.
1991
Abstract 1. 1. Eel were exposed to a sublethal concentration of lindane (0.335 ppm) for 6, 12, 24, 48, 72 and 96 hr. 2. 2. Concentrations of glycogen, glucose, lactate, pyruvate and lipids were determined in gill tissue after lindane exposure. 3. 3. Gill glycogen descreased and glucose levels increased at 6 hr of treatment, lactate and pyruvate concentration increased between 6 and 48 hr. Total lipid values decreased between 6 and 24 hr; thereafter, the levels increased up to 72 hr of exposure. 4. 4. Clear changes were found in all parameters tested in gill tissues. The observed effects of lindane on metabolism in fish are discussed in relation to acute stress syndrome.
Physiology and genetics of antibiotic production and resistance.
1993
Actinomycetes have the genetic capability to synthesize many different biologically active secondary metabolites and of these compounds, antibiotics predominate in therapeutic and commercial importance. Intensive research often centres on the use of molecular techniques to investigate the physiology and genetics of antibiotic biosynthesis with a view to improving production. The isolation of clones of Streptomyces hygroscopicus, the producer of geldanamycin, which synthesizes geldanamycin in S. lividans, is reported. Molecular approaches using genes for elongation factors (tuf) were used in attempts to increase the fermentation yield of kirromycin, whilst probes for aphD and sph, genes for …
Involvement of actin-containing microfilaments in HSV-induced cytopathology and the influence of inhibitors of glycosylation.
1986
Two and a half hours after infection with a high dose of different strains of HSV-1 which induce rounding of cells, breakdown of actin containing microfilaments can be observed. At the periphery of the cell, actin containing knob-like protuberances were visible. Later on, actin seems to be located exclusively on the surface of cells. Observations were done by immunofluorescence microscopy, scanning electron-microscopy and immunoperoxidase staining of ultrathin sections. The envelope of HSV appears to be stained by anti-actin. Strain IES produces rounding of cells at a high dose of infection before fusion proceeds at 37 degrees C. Similar alterations were not observed with the fusing strains…
Membrane-insertion fragments of Bcl-xL, Bax, and Bid.
2004
Apoptosis regulators of the Bcl-2 family associate with intracellular membranes from mitochondria and the endoplasmic reticulum, where they perform their function. The activity of these proteins is related to the release of apoptogenic factors, sequestered in the mitochondria, to the cytoplasm, probably through the formation of ion and/or protein transport channels. Most of these proteins contain a C-terminal putative transmembrane (TM) fragment and a pair of hydrophobic alpha helices (alpha5-alpha6) similar to the membrane insertion fragments of the ion-channel domain of diphtheria toxin and colicins. Here, we report on the membrane-insertion properties of different segments from antiapopt…
Purification and evaluation of large clostridial cytotoxins that inhibit small GTPases of Rho and ras subfamilies
2000
Publisher Summary This chapter discusses the purification and evaluation of large clostridia cytotoxins (LCTs) that inhibit small guanosine 5'-triphosphates (GTPases) of Rho and Ras subfamilies. LCTs are glycosyltransferases that inactivate GTPases of the Rho and Ras subfamilies by covalently coupling a sugar moiety (mostly glucose) to the conserved threonine residue in region switch 1 of the GTPases (T35 in Ras). This glycosylation functionally inactivates the GTPases leading to the collapse of the actin cytoskeleton and ultimately induces apoptosis of the cells. Small GTP-binding proteins are key players in the regulation of signal transducing networks of eukaryotic cells. Their regulator…
�ber den Saccus vasculosus einiger Teleosteer
1954
I. Der Saccus vasculosus der Makrele, zeigt, abgesehen von seiner Lage, keine Besonderheiten gegenuber dem anderer Teleosteer. Unerklart mussen vorlaufig die dunkelgefarbten Granula im Epithel bleiben. Sie nur als Farbniederschlage zu deuten, erscheint nicht befriedigend, da sie nur im Saccus vorkommen. II. Der verschiedene Fullungszustand von Capillaren einerseits und Blutsinus andererseits im Saccus von Sebastes norvegicus lenkt unsere Aufmerksamkeit auf die noch nicht ganz geklarten Blutgefasversorgungsverhaltnisse des Saccus. Es ist an die Moglichkeit verschiedener Blutversorgung von Sinus und Capillaren zu denken, wie auch Scharrer (1948) vermutete. III. Die phasenkontrastoptischen Beo…
Multicentre study of gestrinone in cyclical breast pain FRIEDOLF PETERS
1992
Although the aetiology of cyclical mastalgia is poorly understood, the consistent finding of an increased prolactin stimulation response probably due to oestrogen dominance has led to the use of treatment with prolactin-lowering drugs and antioestrogens. The efficacy and safety in cyclical mastalgia of gestrinone, which has androgenic, anti-oestrogenic, and antiprogestagenic properties, were investigated in a multicentre study. In a double-blind randomisation procedure, 72 patients were allocated placebo and 73 treatment with gestrinone (2.5 mg twice a week) for 3 months. The patients recorded the severity of breast pain on a visual analogue scale before and during treatment and scored othe…