Vitamin losses during frozen storage of Liza aurata (Risso, 1810), Cyprinus carpio L. 1758, Clupeonella cultriventris caspia (Nordmann, 1840), Rutilus frisii kutum (Kamenskii, 1901) and Sander lucioperca (L., 1758)

The objective of this study was to determine the fat and water‐soluble vitamins contents (A, E, D, K, B₁, B₂, B₆, B₁₂, niacin, biotin, ascorbic, folic and pantethonic acids; in mg kg^?1 fresh weight) lost during frozen storage (?24°C) in time intervals of 0, 1, 2, 3 and 4 months. Studied species included: Liza aurata (golden grey mullet), Cyprinus carpio (common carp), Clupeonella cultriventris caspia (common kilka or sprat), Rutilus frisii kutum (Caspian kutum) and Sander lucioperca (pike perch). Results showed that A, D and K vitamin losses occurred in all samples during storage, but no statistically significant differences were observed. Vitamin E losses under frozen conditions were significant in common kilka, Caspian kutum and pike perch, however, not in golden grey mullet or common carp. A decrease in vitamin C was significant in all fish species, but there were no significant decreases in other water‐soluble vitamins (B₁, B₂, B₆, B₁₂, niacin, folic acid, pantothenic acid, biotin).     

Ultrastructure of spermiogenesis in Liza aurata Risso, 1810 (Teleostei,Mugilidae)

Summary Sequential cytological events in late spermatogenesis of Liza aurata were studied from the stage secondary spermatocytes to that of mature spermatozoa. Spermiogenesis involves preparatory morphological events followed by conspicuous modifications such as intracellular movements (diplosome and mitochondrion migration, spermatid lengthening, nuclear rotation) and structural changes (dense chromatin granules, increase in size of mitochondria, loss of cytoplasm). Mature spermatozoa, with a round nucleus and a pseudo-midpiece are of a primitive type, even compared with spermatozoa of other teleosts.     

The use of carp, Cyprinus carpio (Linnaeus, 1758), instead of rabbit as antibody donor in immunological research on fishes.

Antisera produced by carp were tested in the differentiation between two cyprinid fishes, bream and roach, and between the lipovitellins of two grey mullets, Mugil cephalus and Liza ramada. These antisera were more specific in the recognition of different fish species than those produced by rabbits. An antiserum against carp lipovitellin was produced with male carp as antibody donor.     

The use of carp, Cyprinus carpio (Linnaeus, 1758), instead of rabbit as antibody donor in immunological research on fishes

Antisera produced by carp were tested in the differentiation between two cyprinid fishes, bream and roach, and between the lipovitellins of two grey mullets, Mugil cephalus and Liza ramada. These antisera were more specific in the recognition o! different fish species than those produced by rabbits.
An antiserum against carp lipovitellin was produced with male carp as antibody donor.     

Maturity and fecundity of golden grey mullet (Liza aurata Risso, 1810) in Iranian waters of the Caspian Sea

The objective of the study was to determine some reproductive parameters in the golden grey mullet (Liza aurata Risso, 1810) during two periods half a decade apart while also trying from limited data to identify changes in fecundity over the past half century. Maturity and fecundity of golden grey mullet caught in Iranian waters of the Caspian Sea is not well documented and were thus studied during several seasonal cycles during 2002–2004 to establish basic data on reproduction in the area. The fork length (FL) of 462 sampled fish was between 22.1 and 51.9 cm. The fork length–weight relationship derived from all fish was W = 0.0118FL^2.964. Overall male to female ratio was 1 : 1.42. The reproductive season extended from October to December. Fifty percent of sexual maturity was at FL 26.0 cm. Mature gonads were present in 20% of fish at age 3, 63% at age 4, 88% at age 5, and 97% at age 6. Individual absolute fecundity of the golden grey mullet ranged from 113 386 to 1.47 million eggs, with a mean (±SD) of 451 963 (±274,114.2). An overlap exists between the spawning and fishing seasons. Therefore, the start of the fishing season should be delayed for 1 month in order for stocks to complete their spawning.     

Comparative immunofluorescence and ultrastructural analysis of microtubule organization in Uronema sp., Klebsormidium flaccidum, K. subtilissimum, Stichococcus bacillaris and S. chloranthus (Chlorophyta)

A detailed comparative examination of microtubule (MT) organization in interphase and dividing cells of Uronema sp., Klebsormidium flaccidum, K. subtilissimum, Stichococcus bacillaris and S. chloranthus was made using tubulin immunofluorescence and transmission electron microscopy (TEM). During interphase all the species bear a well-organized cortical MT system, consisting of parallel bundles with different orientations. In Uronema sp. the cortical MT bundles are longitudinally oriented, whereas in the other species they are in transverse orientation to the axis of the cells. Considerable differences in MT organization were also observed during stages of mitosis, mainly preprophase, as well as cytokinesis. In Uronema sp., a particular radial MT assembly is organized during preprophase-early prophase, which was not observed in the other species. In Stichococcus a fine MT ring surrounded the nucleus during preprophase and prophase. An MT ring, together with single cytoplasmic MTs, was also found associated with the developing diaphragm during cytokinesis in Stichococcus. A phycoplast participates in cytokinesis in Uronema sp., but not in the other species. In Uronema sp. the centrosome functions as a microtubule organizing center (MTOC) during mitosis, but not during interphase and cytokinesis. The phylogenetic significance of these differences is discussed in combination with SSU/ITS sequencing and other, existing molecular data.     

A study on the scales and age estimation of the grey golden mullet, Liza aurata (Risso, 1810), in the lagoon of Messolonghi (W. Greece)

A detailed study was made of the scales on the golden grey mullet Liza aurata in the lagoon of Messolonghi (W. Greece), in order to examine the suitability of scales for ageing. From a total of 1048 specimens of 9–59 cm total length (TL), the estimated ages ranged from 0+ to 8+ years, with only females at ages 7+ and 8+. The scale reading was reliable, the annuli recognizable and each annulus radius easily measured. There was a great overlapping in the annulus radius between the ages 1+ and 4+, indicative of extended spawning time and differences in growth of yearly recruits. The scale radius (R_max) was strongly related with TL by the pooled equation: TL = 1.5501R_max^0.77, with no significant differences between the sexes. From examination of the monthly variation in the distance of the outermost annulus from the scale margin, it was determined that the annulus is formed in February. No annuli were detected in fish of less than 20 cm TL.     

Spatial and temporal variations and assemblage structure of fish species in Beymelek Lagoon,Turkey

Spatial and temporal variations and assemblage structure of fish species were investigated in Beymelek Lagoon, on the south‐western Mediterranean coast of Turkey. A total of 3956 fish, mainly juveniles, from 24 species representing 11 families were sampled by gillnets and trammel nets from February 2006 to January 2007. Twelve of the species were marine straddlers, 11 were marine‐estuarine‐dependent and one was catadromous. Numerical contribution of marine‐estuarine‐dependent species to the total fish abundance was 86.2%, while marine straddlers contributed only 13.8%. Despite the higher number of species, the numerical abundance of marine straddlers was lower than the abundance of marine‐estuarine‐dependent species. The contribution of catadromous species by number was only 0.02%. The assemblage was taxonomically dominated by Sparidae (seven species, 51.3%), Mugilidae (five species, 36.0%), and Clupeidae (one species, 10.3%). Among sparids, Sparus aurata, Diplodus sargus and Lithognathus mormyrus contributed 38.0, 7.2 and 4.6% to the total catch, respectively. The most abundant mugilid species was Liza saliens with 25.2%, followed by Chelon labrosus 5.2%, and Liza aurata 4.0%. Contribution by the other mugilid species to total catch was quite low. The Clupeidae (10.3%) were represented by Sardinella maderensis with 9.1% of the total catch. While the upper reaches of Beymelek Lagoon were dominated by Sparus aurata and Liza saliens, dominant in the lower reaches were Sardinella maderensis, Sparus aurata, Diplodus sargus, Lithognathus mormyrus and Liza saliens. Sparids were generally caught from mid‐summer to mid‐winter while mugilids were caught throughout the year. Clupeids occurred mainly from autumn to spring.     

Fishery, seasonal abundance and mortality of grey mullets (Pisces: Mugilidae) in Negombo Lagoon, Sri Lanka

The seasonal abundance and instantaneous natural and fishing mortalities of six species of grey mullets, namely Liza subviridis, L. macrolepis, L. tade, Mugil cephalus, Valamugil buchanani and V. cunnesius were studied as a prelude for the management of their fishery in Negombo lagoon (7°10′N and 79°50′E). L. subviridis was the most abundant of the grey mullet species in the commercial catches and accounted for 37% of the total grey mullet catch. M. cephalus was the least abundant and constituted 6%. The annual catch of grey mullets was estimated to be around 23 000 kg (5.67 kg/ha); about 40 % of the total fish landings of the lagoon. The seasonal variation in the catch of different species of grey mullets appear to be related to their breeding seasons and spawning migrations. The highest value for instantaneous natural and fishing mortalities, which were 1.04 and 0.94 respectively were obtained for V. cunnesius. The lowest values for instantaneous natural and fishing mortalities which were 0.51 and 0.19 respectively were obtained for M. cephalus. The exploitation ratios calculated were less than 0.5 for all species other than L. tade which suggest that the grey mullet populations excluding L. tade in this lagoon may presently be underexploited.     

小鼠正常肝、再生肝和腹水型肝癌H22a细胞酪氨酸蛋白磷酸酶的比较研究

小鼠肝在再生过程中,胞浆酪氨酸蛋白磷酸酶(PTPP)活力比正常肝有明显升高,并且伴有时相变化,,手术后24—48h活力达到最高,而H22a细胞各组分的活力都比正常肝低。PTPP在正常肝细胞的溶酶体中分布最高;再生肝中则在细胞核、胞浆和微粒体中更集中;在H22a细胞中,PTPP的活力分布趋于平均化。再生肝和H22a细胞胞浆中都缺少正常肝的a、b两个PTPP活力峰,其它五个主要PTPP峰与正常肝无根本的差别。     

Biogeography and phylogeny of Dermoergasilus Ho & Do, 1982 (Copepoda: Ergasilidae), with descriptions of three new species

Three new species of Dermoergasilus are described from six species of grey mullet hosts. Dermoergasilus longiabdominalis n. sp. was found on Valamugil engeli (Bleeker) from the Philippines and Madagascar and on V. cunnesius (Valenciennes) from the Philippines and Mangalore, India. D. semiamplectens n. sp. occurred on Sicamugil hamiltoni (Day) from the Sittang River, Burma, on Liza subviridis (Valenciennes) and L. parsia (Hamilton Buchanan) from Calcutta, India, and on V. cunnesius (Valenciennes) from China. D. curtus n. sp. parasitised Rhinomugil squamipinnis (Swainson) from Alahabad, India. A key to the ten currently accepted species of Dermoergasilus is given. The biogeographical distribution of Dermoergasilus species is analysed and levels of host-specificity are surveyed within the genus. The phylogenetic relationships between the species of Dermoergasilus are also analysed.     

Stock assessment and management implications of golden grey mullet (Liza aurata Risso, 1810) in Iranian waters of the Caspian Sea

Recent changes in the Caspian ecosystem have caused changes in the absolute and relative abundance of the commercially important golden grey mullet (Liza aurata) in Iranian waters. In order to adjust for these changes a more rigorous management of this fishery resource is required. The present study examines the biomass of golden grey mullet during 1991–2010. Estimates of f_MSY, yield‐per‐recruit and spawning biomass‐per‐recruit are presented for various harvesting strategies of F_max, F_0.1, F_35%, and a method is proposed for estimating acceptable biological catch (ABC) that accounts for large differences in the quality and quantity of information and available data. Biomass estimates of golden grey mullet, derived from a biomass‐based cohort analysis, increased from 13 527 tonnes in 1991–1992 to 20 100 t in 2000–2001, and declined to the lowest level (11 000 t) in 2007–2008. In 2009–2010, the total biomass was estimated to be 14 400 t. The ABC was estimated at 2200 t in 2010. Golden grey mullet is vulnerable to environmental factors, which should be considered in the stock assessment and management of the fish.     

Effect of metabolic alterations on the density and the contents of cathepsins B, H and L of lysosomes in rat macrophages

Crude lysosomal preparations from non-cultured peritoneal rat macrophages were shown to separate into high-density fractions rich in cathepsin B and H and low-density fractions rich in cathepsin L when layered on Percoll density gradients. Morphologically, the heavy lysosome fractions were found to consist mainly of lysosomes labeled with gold particles for anti-(cathepsin B, H and L). The light lysosome fractions contained lysosomes labeled with anti-(cathepsin B, H and L) and many other contaminants. In addition, small vesicles labeled by anti-(cathepsin L) were detected in these fractions. Addition of calf serum to the cultured macrophages induced an increase in the density of lysosomes in both dose-dependent and time-dependent fashions. Cathepsins B, H and L all shifted to the heavy lysosome fractions following the addition of serum. Progressive increase in fluorescence-labeled calf IgG in the heavy lysosome fractions after its addition suggests that the continuous entrance of excess proteins to lysosomes causes an increase in their density. This idea is supported by the fact that the density of lysosomes increased in parallel with the accumulation of horseradish peroxidase taken up in the heavy lysosome fractions. Increase in the density of lysosomes after treatment with ethyl(2S,3S)-3[(S)-3-methyl-1-(3-methyl-butylcarbamoyl)]oxirane-2- carboxylate (E-64-d) was marked in the cells cultured with serum-containing medium but slight in serum-deprived cells. However, the level of pyruvate kinase, an autophagic sequestration marker in heavy autolysosomes from E-64-d-treated cells, was much higher in serum-deprived cells, indicating that the contribution of heterophagic sequestration towards an increase in the density of lysosomes is much greater than that of autophagy.     

The biogeochemical role of Actinobacteria in Altamira Cave, Spain

The walls and ceiling of Altamira Cave, northern Spain, are coated with different coloured spots (yellow, white and grey). Electron microscopy revealed that the grey spots are composed of bacteria and bioinduced CaCO(3) crystals. The morphology of the spots revealed a dense network of microorganisms organized in well-defined radial and dendritic divergent branches from the central area towards the exterior of the spot, which is coated with overlying spheroidal elements of CaCO(3) and CaCO(3) nest-like aggregates. Molecular analysis indicated that the grey spots were mainly formed by an unrecognized species of the genus Actinobacteria. CO(2) efflux measurements in rocks heavily covered by grey spots confirmed that bacteria-forming spots promoted uptake of the gas, which is abundant in the cave. The bacteria can use the captured CO(2) to dissolve the rock and subsequently generate crystals of CaCO(3) in periods of lower humidity and/or CO(2). A tentative model for the formation of these grey spots, supported by scanning electron microscopy and transmission electron microscopy data, is proposed.     

Phenetic relationships of six species of mullets (<Emphasis Type="Italic">Mugilidae</Emphasis>) from the south Adriatic,as inferred from the study of the visceral and dermal skeleton

This study examines the interspecific variability and phenetic relationships in six southern Adriatic mullet species: Mugil cephalus (Linnaeus, 1758), Chelon labrosus (Risso, 1826), Liza aurata (Risso, 1810), Liza ramada (Risso, 1826), Liza saliens (Risso, 1810), and Oedalechilus labeo (Cuvier, 1829). Twenty-three morphometric characteristics of the visceral skeleton and the dermatocranium of mullets were analyzed. The major distinguishing characters were those of the jaws. M. cephalus was clearly separated from the other species; O. labeo differed to a somewhat smaller extent; and C. labrosus was the least distinguished species. The species of the genus Liza were phenetically most similar, while the other species of mullet differed significantly from them. The greatest distances were between M. cephalus and C. labrosus, as well as between M. cephalus and O. labeo. This text was submitted by the authors in English.     

Biochemical Characterization and Distribution of Glutathione S-Transferases in Leaping Mullet (Liza saliens)

In this study, feral leaping mullet (Liza saliens) liver cytosolic glutathione S-transferases (GSTs) were investigated and characterized using 1-chloro-2,4-dinitrobenzene (CDNB) and ethacrynic acid (EA) as substrates. The average GST activities towards CDNB and EA were found to be 1365 +/- 41 and 140 +/- 20 nmol/min per mg protein, respectively. The effects of cytosolic protein amount and temperature ranging from 4 to 70 degrees C on enzyme activities were examined. While both activities towards CDNB and EA showed similar dependence on protein amount, temperature optima were found as 37 and 42 degrees C, respectively. In addition, the effects of pH on GST-CDNB and -EA activities were studied and different pH activity profiles were observed. For both substrates, GST activities were found to obey Michaelis-Menten kinetics with apparent V(max) and K(m) values of 1661 nmol/min per mg protein and 0.24 mM and 157 nmol/min per mg protein and 0.056 mM for CDNB and EA, respectively. Distribution of GST in Liza saliens tissues was investigated and compared with other fish species. Very high GST activities were measured in tissues from Liza saliens such as liver, kidney, testis, proximal intestine, and gills. Moreover, our results suggested that GST activities from Liza saliens would be a valuable biomarker for aquatic pollution.     

Sperm cells in pollen tubes ofNicotians tabacum L.: three-dimensional reconstruction,cytoplasmic diminution,and quantitative cytology

Summary The organization of the sperm cells and vegetative nucleus (male germ unit) ofNicotiana tabacum was examined 18 h after semivivo pollination using transmission electron microscopy, computerassisted serial section reconstruction and quantitative cytology. Based on a measurement of 11 cellular parameters in nine reconstructed sperm cell pairs, there are no statistically significant differences between the two cells. The S_vn is characterized by a strapshaped cytoplasmic extension that is physically associated with the surface of the vegetative nucleus. The nucleus is located adjacent to the sperm crosswall, with sperm organelles being distributed between the nucleus and the extension. The S_ua is a tapered cell with cytoplasmic areas at both poles and deep axial invaginations near the crosswall. This cell has a centrally-located nucleus and a largely polar distribution of organelles. Three mechanisms for cytoplasmic diminution were observed that appear to contribute actively to the loss of cytoplasmic volume and organelles: (1) enucleated cytoplasmic body production in the S_ua; (2) vesiculation at the tip of the cytoplasmic projection of the S_vn; and (3) vesicle-containing body accumulation in the periplasm of both the S_vn and S_ua.Abbreviations 3-D three-dimensional - ECB enucleated cytoplasmic body - MGU male germ unit - S_vn leading sperm cell - S_ua trailing sperm cell - TEM transmission electron microscopy - VCB vesicle-containing body     

Metabolic interactions between animal cells through permeable intercellular junctions.

The isolated perfused rat liver was used to study the degradation of ¹²⁵I-labelled protein supplied in the perfusion medium. Formaldehyde-denatured proteins (human serum albumin, bovine serum albumin and especially rat liver phosphoenolpyruvate carboxykinase (GTP)) were taken up by the liver and degraded at high rates. Native human serum albumin was not degraded at significant rates by the perfused liver, while native phosphoenolpyruvate carboxykinase (GTP) was catabolised at about one-fourth the rate of the denatured enzyme. The degradation rate of denatured human serum albumin increased markedly as protein was added up to 0.7 mg, and more gradually with further increases in added protein. The biphasic nature of concentration dependence probably reflects the contribution of different cell types in the liver. Autoradiographic examination of serial biopsies taken during perfusion of the liver with formaldehyde-denatured, ¹²⁵I-labelled bovine serum albumin showed that at the cellular level the radioactivity was located predominantly in Kupffer and other non-parenchymal cells; and at the subcellular level the radioactivity was largely in endocytic vesicles, lysosomes and occasionally in the sinusoidal spaces. No significant radioactivity was found associated with other cytoplasmic organelles or the nucleus. It is concluded that lysosomes of the non-parenchymal cells are primarily responsible for the degradation of denatured extracellular protein that enters the liver.