Length–weight and length–length relationships for three Sillago species (Sillaginidae) from the Persian Gulf

This study investigates length–length and length–weight relationships of three Sillago species [Sillago arabica McKay & McCarthy (Memoirs of the Queensland Museum, 27, 1989, 551), Sillago attenuata McKay, 1985 and Sillago sihama (Forsskål, 1775)] captured in the Persian Gulf, Iran. A collection of 220 specimens was captured from August 2015 to January 2016 by cast net (mesh size: 10 mm) and beach seine (mesh size: 15 mm). The relationships of total length (TL) and standard length (SL) and the relationships between total length and body weight are given. This study presents the first reference on LWRs for two of the species (S. arabica and S. attenuata) in their range of distribution.     

Length–weight relationships of five commercial fish species from the Strait of Hormuz in the Persian Gulf

Length‐weight relationships are described for five fish species from the coast of the Hormuz Strait in the Persian Gulf, Iran. Specimens were collected between August 2010 and July 2011 using shrimp beam trawls, gill nets and intertidal fishing weirs. Relationships for three of the species had no previous data in the international science global databank on fishes: www.FishBase.org . A new maximum length was recorded for Acanthopagrus latus.     

Adverse effects of tempol on hidrosaline balance in rats with acute sodium overload

We studied the effects of tempol, an oxygen radical scavenger, on hydrosaline balance in rats with acute sodium overload. Male rats with free access to water were injected with isotonic (control group) or hypertonic saline solution (0.80 mol/l NaCl) either alone (Na group) or with tempol (Na-T group). Hydrosaline balance was determined during a 90 min experimental period. Protein expressions of aquaporin 1 (AQP1), aquaporin 2 (AQP2), angiotensin II (Ang II) and endothelial nitric oxide synthase (eNOS) were measured in renal tissue. Water intake, creatinine clearance, diuresis and natriuresis increased in the Na group. Under conditions of sodium overload, tempol increased plasma sodium and protein levels and increased diuresis, natriuresis and sodium excretion. Tempol also decreased water intake without affecting creatinine clearance. AQP1 and eNOS were increased and Ang II decreased in the renal cortex of the Na group, whereas AQP2 was increased in the renal medulla. Nonglycosylated AQP1 and eNOS were increased further in the renal cortex of the Na-T group, whereas AQP2 was decreased in the renal medulla and was localized mainly in the cell membrane. Moreover, p47-phox immunostaining was increased in the hypothalamus of Na group, and this increase was prevented by tempol. Our findings suggest that tempol causes hypernatremia after acute sodium overload by inhibiting the thirst mechanism and facilitating diuresis, despite increasing renal eNOS expression and natriuresis.     

Electrophysiologic study of rabbit proximal tubular cell monolayers in primary culture

Primary cultures of renal cortical cells prepared by selective sieves have been found to display some characteristics of renal proximal tubular epithelium but their site of origin has not been confirmed by electrophysiologic studies. Cells were cultured in a defined medium on collagen gels. Confluency was approached after 7-10 days but gels were found to have zero transepithelial resistance unless they were allowed to contract spontaneously. With the appearance of a nonzero resistance, there was a change in morphology to a more columnar cell with better developed microvilli. These structural features were particularly prominent in clusters of proliferating cells observed on and around remnants of original tubules embedded in the gel. In noncontracted cultures there was no focal cell clustering and cells were squamous-like with rudimentary microvilli, similar in appearance to cells grown on plastic culture dishes. Measurements made in contracted monolayers yielded an average transepithelial resistance of 6.5 omega cm2, a spontaneous transepithelial potential difference of +0.9 mV, measured with respect to the serosa, and an apical membrane potential of -75 mV when cells were bathed in 0.4 mM K and -49 mV when cells were bathed in 4 mM K media. Mucosal protamine (50 micrograms/ml) increased transepithelial resistance by 22%, suggesting that the epithelial cell tight junctions were responsive to external stimuli. Monolayers were anion selective, giving a dilution potential (lumen-directed NaCl gradient) of -2.6 mV with respect to the serosa. These experiments show that primary culture of rabbit renal cortical cells separated by differential sieves displays electrophysiologic and morphologic characteristics of a proximal renal tubular epithelium. Confluency and attainment of differentiated morphology and function are promoted when monolayer cells are not bound to an unyielding substrate.     

Sulfated proteoglycans of rabbit aorta: selective extraction and alternative method for glycosaminoglycan moiety analysis.

Three different solutions containing urea, guanidine hydrochloride, or a detergent mixture were used to extract proteoglycan molecules (PG) metabolically labeled with 35S from normal rabbit aortic tissue. The size distribution of whole sulfated PG and the glycosaminoglycan (GAG) compositions in the three extracts were compared and found to be characteristically determined by the type of solution used for extraction. The spectrum of sulfated PG isolated by each solution was maintained at consecutive extractions of the tissue, even if this was used after another type of solution. The extracts obtained by using the urea- or guanidine-containing solutions contained similar, rather balanced populations of large and small PG, while the detergent-containing buffer was found to preferentially extract smaller, heparan sulfate-rich aortic PG. The selectivity of various extracting solutions could be exploited to obtain preparations enriched in certain types of sulfated PG. On the other hand, one could obtain a larger variety of 35S-labeled PG from the tissue by consecutively using two solutions with different capacities of extraction. The distribution of GAG moieties among PG populations, separated by size chromatography, was investigated by one of the commonly used methods and by a new method. The standard method is based on comparison of the chromatographic profiles of the extract before and after enzymatic digestions, requiring several chromatographic runs for a sample. In the alternative method proposed, the fractions obtained after a single chromatographic separation are adsorbed onto a support membrane. Processing of the whole membrane by GAG-specific, enzymatic treatments allows simultaneous assessment of GAG types in each fraction.(ABSTRACT TRUNCATED AT 250 WORDS)     

Motility of Mugil cephalus L. spermatozoa in coelomic fluid, seminal fluid and saline media

The aim of this study was to assess the motility duration of Mugil cephalus when exposed to seminal fluid, coelomic fluid and saline media. Hypo-osmotic activation medium (distilled water containing bovine serum albumin 10 or 30 mg ml⁻¹) did not trigger sperm motility. Saline solution containing 500 m m NaCl, 3.1 m m KCl, 0.2 m m Tris, 3.4 m m CaCl₂, pH 7.5 initiated the sperm activation and the motility lasted for more than 2 min. Coelomic fluid showed an inhibitory effect for triggering the motility of spermatozoa. Higher salinity increases the motility duration of sperm. The optimum motility duration was shown in salinity 32 psu.     

The dynamics of interactions between Plasmodium and the mosquito: a study of the infectivity of Plasmodium berghei and Plasmodium gallinaceum,and their transmission by Anopheles stephensi,Anopheles gambiae and Aedes aegypti

Knowledge of parasite-mosquito interactions is essential to develop strategies that will reduce malaria transmission through the mosquito vector. In this study we investigated the development of two model malaria parasites, Plasmodium berghei and Plasmodium gallinaceum, in three mosquito species Anopheles stephensi, Anopheles gambiae and Aedes aegypti. New methods to study gamete production in vivo in combination with GFP-expressing ookinetes were employed to measure the large losses incurred by the parasites during infection of mosquitoes. All three mosquito species transmitted P. gallinaceum; P. berghei was only transmitted by Anopheles spp. Plasmodium gallinaceum initiates gamete production with high efficiency equally in the three mosquito species. By contrast P. berghei is less efficiently activated to produce gametes, and in Ae. aegypti microgamete formation is almost totally suppressed. In all parasite/vector combinations ookinete development is inefficient, 500-100,000-fold losses were encountered. Losses during ookinete-to-oocyst transformation range from fivefold in compatible vector parasite combinations (P. berghei/An. stephensi), through >100-fold in poor vector/parasite combinations (P. gallinaceum/An. stephensi), to complete blockade (>1,500 fold) in others (P. berghei/Ae. aegypti). Plasmodium berghei ookinetes survive poorly in the bloodmeal of Ae. aegypti and are unable to invade the midgut epithelium. Cultured mature ookinetes of P. berghei injected directly into the mosquito haemocoele produced salivary gland sporozoites in An. stephensi, but not in Ae. aegypti, suggesting that further species-specific incompatibilities occur downstream of the midgut epithelium in Ae. aegypti. These results show that in these parasite-mosquito combinations the susceptibility to malarial infection is regulated at multiple steps during the development of the parasites. Understanding these at the molecular level may contribute to the development of rational strategies to reduce the vector competence of malarial vectors.     

Acceptor specificity of the human leukocyte alpha3 fucosyltransferase: role of FucT-VII in the generation of selectin ligands

The alpha3 fucosyltransferase, FucT-VII, is one of the key glycosyltransferases involved in the biosynthesis of the sialyl Lewis X (sLex) antigen on human leukocytes. The sialyl Lewis X antigen (NeuAcalpha(2-3)Galbeta(1-4)[Fucalpha(1-3)]GlcNAc-R) is an essential component of the recruitment of leukocytes to sites of inflammation, mediating the primary interaction between circulating leukocytes and activated endothelium. In order to characterize the enzymatic properties of the leukocyte alpha3 fucosyltransferase FucT-VII, the enzyme has been expressed in Trichoplusia ni insect cells. The enzyme is capable of synthesizing both sLexand sialyl-dimeric-Lexstructures in vitro , from 3'-sialyl-lacNAc and VIM-2 structures, respectively, with only low levels of fucose transfer observed to neutral or 3'-sulfated acceptors. Studies using fucosylated NeuAcalpha(2-3)-(Galbeta(1- 4)GlcNAc)3-Me acceptors demonstrate that FucT-VII is able to synthesize both di-fucosylated and tri-fucosylated structures from mono- fucosylated precursors, but preferentially fucosylates the distal GlcNAc within a polylactosamine chain. Furthermore, the rate of fucosylation of the internal GlcNAc residues is reduced once fucose has been added to the distal GlcNAc. These results indicate that FucT-VII is capable of generating complex selectin ligands, in vitro , however the order of fucose addition to the lactosamine chain affects the rate of selectin ligand synthesis.