Damage, recovery and survival of 0-group mulloway, Argyrosomus japonicus, after simulated escape through square mesh

A laboratory experiment was carried out to quantify and compare the physical damage (measured as scale loss), recovery and survival of two size categories [small: 48–85 mm total length (TL); large: 78–148 mm TL] of 0‐group mulloway, Argyrosomus japonicus, after simulated escape through square‐shaped mesh (bar length of 21.5 mm). Regardless of their size, fish that were fatigued to exhaustion and forced through square meshes sustained significantly more (i.e. >1.8 times) scale loss than did control fish that were only fatigued. However, the total scale loss incurred was <5% and significantly improved 7 days after treatment. Survival rates over a 2‐week observation period were 100 and >97% for treatment and control fish, respectively. The results support the utility of square mesh for reducing the prawn‐trawl fishing mortality of unwanted bycatch.     

Synopsis of biological, fisheries and aquaculture-related information on mulloway Argyrosomus japonicus (Pisces: Sciaenidae), with particular reference to Australia

Argyrosomus japonicus is a member of the family Sciaenidae, which are commonly known as drums and croakers. A. japonicus occurs in estuarine and nearshore Pacific Ocean and Indian Ocean waters surrounding Australia, Africa, India, Pakistan, China, Korea and Japan. The biology of A. japonicus is relatively well studied in South Africa, and more recently studied in Australia, but no information is readily available from other areas of its distributional range. The early life history distribution of A. japonicus may differ among regions, with their distribution in estuaries linked to salinity, turbidity, freshwater flows and depth of water. Studies in South Africa and Australia found that juvenile fish grow rapidly, attaining 35 cm TL in 1 year and 87–90 cm TL in 5 years. Sexual maturity also differs among regions and is attained at 2–3 years of age and >50 cm in eastern Australia, 5–6 years of age and >80 cm TL in western Australia and southern Africa. The maximum reported length and age of A. japonicus is 175 cm and 42 years, respectively. Spawning most likely occurs in nearshore coastal waters although there is evidence to suggest that it may also occur in the lower reaches of estuaries. Time of spawning varies among geographic localities and is probably linked to water temperature and oceanography. Juvenile fish (<2 years) appear to be relatively sedentary, but sub‐adults and adults can move relatively long distances (>200 km) and such movements may be linked to pre‐spawning migrations. A. japonicus is important in many recreational and commercial fisheries, but like other sciaenids, is prone to overfishing. It is classified as recruitment overfished in South Africa and overfished in eastern Australia. Although much research has been done to minimize the capture of juveniles in Australian prawn‐trawl fisheries, greater protection of spawners and improved fishing practices to enhance survival of discarded juveniles, particularly from prawn trawling, may be required. An aquaculture industry is developing for A. japonicus in Australia and preliminary research on the impacts and success of re‐stocking wild populations has begun in an attempt to arrest the apparent decline in populations.     

Isolation and characterization of 15 polymorphic microsatellite DNA loci from Argyrosomus japonicus (mulloway), a new aquaculture species in Australia

Fifteen microsatellite loci were isolated for population genetic studies of mulloway (Argyrosomus japonicus), a commercial/recreational fish species in Southern Australia. A genomic library was screened randomly for di- tri- and tetranucleotide repeats. Fifteen microsatellite marker loci were developed that were highly polymorphic (allele number ranged from four to 18). Observed and expected heterozygosities ranged from 0.17 to 1 and from 0.27 to 0.91, respectively. These markers have proven useful for estimating genetic variation and for evaluating population structure across the species' natural distribution. They also provide powerful tools for optimizing hatchery practices to conserve genetic diversity.     

Perhexiline maleate-induced lipidosis in cultured human fibroblasts: cell kinetics, ultrastructural and biochemical studies

Perhexiline maleate reduced the growth of human skin fibroblasts in cell culture at a concentration range of 0.3-3 micrograms/ml. At the highest concentration, the cells survived only four days. Pleomorphic inclusions characteristic of drug-induced phospholipidoses appeared in cultured cells. Analysis of the major lipid classes was performed on cells exposed to 3 micrograms/ml at four days. Gangliosides, phospholipids and cholesterol levels four to six times above controls were found. No major qualitative abnormalities were detected in phospholipids. On the contrary, an abnormal pattern of gangliosides was seen by densitometry of silica gel thin-layer plates with increases of GD3 and of an unknown ganglioside. Drug induced lipidosis may involve other lipids than phospholipids, particularly gangliosides.     

养殖乌鳢类立克次体感染的超微病理学研究

应用电子显微镜技术,观察了养殖乌鳢RLO感染主要内脏器官超微结构病理变化,并初步探讨了发病机制。观察发现：RLO寄生细胞明显肿大,胞质电子密度低,细胞器肿大、溶解,RLO可随肿胀、破裂的细胞进人组织间隙;在一些寄生细胞内尚发现变性的RLO。内脏组织细胞普遍肿大,细胞器分散、稀少,线粒体除明显肿胀、嵴断裂消失外,尚发现坏死性变化即出现致密核心或无定形的电子密度物质;粗面内质网扩张、破裂和脱颗粒;部分细胞内溶酶体增多,胞质内发现明显的髓鞘样结构;核肿大或核固缩、溶解,并可见核内出现髓鞘样结构和核包含物。     

Scrotal angiokeratoma (Fordyce): histopathological and ultrastructural findings.

Bioptic findings related to four cases of scrotal angiokeratoma-Fordyce, were studied under light and electron microscopy. A particular heterogeneity of the structural and ultrastructural patterns typical of this lesion was thus observed. Light microscopy study pointed out, in particular, different degrees of dilation of papillary vessels, whereas ultrastructural study highlighted marked alterations of endothelial cells with structural and quantitative modifications of cytoplasmic organelles.     

Development and ossification of the feeding apparatus in the larvae of two co‐occurring species of kob (Sciaenidae), Argyrosomus japonicus and Argyrosomus inodorus,in South Africa

The teeth of the oral jaws of two sympatric species of Argyrosomus, Argyrosomus japonicus and Argyrosomus inodorus, found along the South African coast developed first on the premaxilla and then on the dentary of the lower jaw. Teeth were observed on the premaxilla of A. inodorus [head length (L_H) = 1·0 mm; notochord length (L_N) = 2·7 mm] at a smaller size than in A. japonicus (L_H = 1·2 mm; L_N = 4·7 mm). The ventral elements of the gill arches (hypo‐ and basibranchials) were not ossified by the end of preflexion. The fifth ceratobranchial began ossifying and possessed pharyngeal teeth by 1·2 mm L_H (L_N = 4·7 mm) in A. japonicus and 1·1 mm L_H (L_N = 3·2 mm) in A. inodorus. To complement the osteological data, stomach contents were also analysed as a proxy for feeding apparatus functionality. Prey were first present in the stomach of A. japonicus at 1·2 mm L_H (L_N = 4·7 mm) and only 22% of the stomachs contained no prey suggesting that A. japonicus is already actively foraging by preflexion. In comparison, 83% of the stomachs of A. inodorus contained no prey and a single prey item was present in the largest examined specimen (L_H = 1·6 mm; L_N = 5·4 mm). Elements of the feeding apparatus begin to ossify early during ontogeny. While the overall pattern of ossification is similar between the two species, A. japonicus may be able to begin feeding at smaller head lengths relative to A. inodorus in their nursery habitats.     

Release method and anatomical hook location: effects on short-term mortality of angler-caught Acanthopagrus australis and Argyrosomus japonicus

One field and 3 aquaria experiments were done to quantify the short-term mortality of yellowfin bream Acanthopagrus australis and mulloway Argyrosomus japonicus after being angled and subjected to 3 general handling treatments. Anglers were supplied with identical J-type hooks and asked to handle hooked fish by either (1) physically removing the hook or (2) cutting the line (5 cm from the mouth of the fish) and leaving the hook in. Some hooked A. japonicus were subjected to a third handling treatment where the line was cut underwater without exposing the fish to air. Technical and biological data were collected before all fish were released into sea cages and monitored for 5 d. Control fish were seined and similarly caged and monitored. Concentrations of plasma glucose and cortisol were collected from a sample of fish on the first and last day of the experiments. Significant predictors of mortality for both species involved the presence of blood at the mouth and an interaction between anatomical hook location and hook removal. A. australis and A. japonicus that had their ingested hooks removed experienced the greatest mortalities (87.5 and 72.7%, respectively). Typically, these fish suffered damage to their oesophagus, stomach wall and vital organs. Mortality rates of A. australis and A. japonicus were significantly decreased to 1.7 and 16%, respectively, when they were released with their lines cut, with some of these fish free of hooks after 5 d. In contrast, few mortalities occurred in either species when the hooks were removed or the lines cut on mouth-hooked fish or in A. japonicus when it was released with no air exposure. For A. australis, the field- and aquaria-based experiments provided comparable results in terms of identifying treatment-specific effects, but there were potential biases in rates of hook ingestion. Irrespective of the treatment of fish, all experiments caused physiological changes measured as elevations in either plasma cortisol or glucose. We concluded that anglers should cut the line from hook-ingested A. australis and A. japonicus, but remove the hook from mouth-hooked individuals to prevent subsequent ingestion. Further research is required to examine the longer-term consequences of these handling practices on fish health.     

Histotypic angiogenesis in vitro: light microscopic, ultrastructural, and radioautographic studies

A model for the study of angiogenesis in vitro is described. Rat aortas, cultured in a tridimensional matrix of clotted chick plasma, gave rise to luxuriant outgrowth of vascular channels. We studied this process with light microscopic, radioautographic, and ultrastructural techniques. On the 2nd d of culture, endothelial cells sprouted from the intima of the aorta and its collateral branches into the surrounding clot, forming solid cellular cords. A complex vascular network was established within the 1st wk by spindly, poorly differentiated endothelial cells. At this stage cells were migrating, branching, and proliferating in a longitudinal fashion (labeling index: 67.4% +/- 7.7). Lumens, when present, appeared as slitlike spaces enclosed with junctional complexes. By the end of the 2nd wk the migratory activity decreased and proliferation occurred mostly in a cross-sectional plane, with formation of large patent lumens (labeling index: 48% +/- 3.1). Vascular channels were lined by prominent endothelial cells rich in rough endoplasmic reticulum, polysomes, mitochondria. Golgi apparatuses, and coated vesicles. Cells were enveloped with a ruthenium red positive layer, particularly abundant on the luminal surface and in the interendothelial space. A discontinuous basal lamina was present along the abluminal side. At 28 d the labeling index was reduced to 2.25% +/- 0.9. The still viable endothelium exhibited numerous microfilaments and microtubules, decreased cytoplasmic organelles, and increased pinocytotic activity. This experimental model, histophysiologic gradient culture, provides us with a new tool for the study of vascular morphogenesis, angiogenesis dependent growth of tumors, and neoplastic intravasation.     

Histotypic angiogenesis in vitro: Light microscopic,ultrastructural, and radioautographic studies

Summary A model for the study of angiogenesis in vitro is described. Rat aortas, cultured in a tridimensional matrix of clotted chick plasma, gave rise to luxuriant outgrowth of vascular channels. We studied this process with light microscopic, radioautographic, and ultrastructural techniques. On the 2nd d of culture, endothelial cells sprouted from the intima of the aorta and its collateral branches into the surrounding clot, forming solid cellular cords. A complex vascular network was established within the 1st wk by spindly, poorly differentiated endothelial cells. At this stage cells were migrating, branching, and proliferating in a longitudinal fashion (labeling index: 67.4% ± 7.7). Lumens, when present, appeared as slitlike spaces enclosed with junctional complexes. By the end of the 2nd wk the migratory activity decreased and proliferation occurred mostly in a cross-sectional plane, with formation of large patent lumens (labeling index: 48% ± 3.1). Vascular channels were lined by prominent endothelial cells rich in rough endoplasmic reticulum, polysomes, mitochondria, Golgi apparatuses, and coated vesicles. Cells were enveloped with a ruthenium red positive layer, particularly abundant on the luminal surface and in the interendothelial space. A discontinuous basal lamina was present along the abluminal side. At 28 d the labeling index was reduced to 2.25% ± 0.9. The still viable endothelium exhibited numerous microfilaments and microtubules, decreased cytoplasmic organelles, and increased pinocytotic activity. This experimental model, histophysiologic gradient culture, provides us with a new tool for the study of vascular morphogenesis, angiogenesis dependent growth of tumors, and neoplastic intravasation. This research was supported by grants from The National Institutes of Health, N.C.I., National Bladder Cancer Project (CA 14137), the Ruth Estrin Goldberg Memorial Fund for Cancer Research, and an American Cancer Society Institutional Research Grant (IN-125A).     

The phylogeny of rotifers: molecular,ultrastructural and behavioural data

This work discusses the nature and significance of molecular, ultrastructural, and behavioural characters that can be used in phylogenetic analyses of rotifers.Recent molecular research has demonstrated the presence of very small amounts of 4-hydroxyproline in rotifers, probably arising from acetyl-cholinesterase or glycoproteins. Thus, rotifers appear to be the first known Metazoa without collagen.Ultrastructural work also has made some interesting discoveries. (1) The myelinic cuticle of the integument and pharynx of gastrotrichs is present in the pharynx of at least two rotifers (Philodina and Brachionus) and some Annelida. (2) The intracytoplasmic lamina (IL) of the syncytial ingestive integument of Acanthocephala is similar to the IL of the syncytial stomach of Bdelloidea. (3) The fibrous terminal web of primitive epidermal ciliated cells may have evolved in the skeletal IL of the syncytial, aciliated integument of rotifers. (4) Using the ultrastructural features of the skeletal, IL of the integument, I derived two possible dendograms of rotifer evolution. (5) These models and other ultrastructural data predict that Bdelloidea should be separated from Monogononta, while Seison has several characters which suggest that it should be more closely aligned to the Monogononta than previously proposed.Molecular and ultrastructural data suggest that rotifers are primitive Metazoa, probably derived by neoteny from ancestral, ciliated larvae. Finally, I argue that information on sensory organs and the behaviour of rotifers may offer unique insights into the evolution of the phylum.     

Phylogenetic relationships of Auriculoscypha based on ultrastructural and molecular studies

The phylogeny of Auriculoscypha anacardiicola, an associate of scale insects in India, is investigated using subcellular characters and MP and Bayesian analyses of combined nuLSU-rDNA, nuSSU-rDNA and 5.8S rDNA sequence data. It has simple septa with a pulley-wheel-shaped pore plug, which is diagnostic of phytoparasitic members of the Pucciniomycetes, and hyphal wall break on branching, a phenomenon unique to some simple septate heterobasidiomycetes. The septal ultrastructure of A. anacardiicola is similar to that of the genus Septobasidium. The close relationship to Septobasidium is also confirmed by rDNA sequence analyses. The polyphyletic nature of the order Platygloeales, noted in earlier studies, is evident from the present molecular analysis as well. The placement of Auriculoscypha in the Platygloeales can no longer be justified and both ultrastructural and molecular evidence strongly support the placement of Auriculoscypha in the Septobasidiales.     

Megaoesophagus in the mouse: histochemical and ultrastructural studies

Histochemical and ultrastructural studies of the muscle coat of the oesophagus from ICRC/HiCri mice (with megaoesophagus) and DBA/2fNCri mice (normal oesophagus) were carried out. The striking observation from histochemical studies was the presence of smooth muscle in the abdominal segment of the oesophagus from ICRC mouse in contrast to the control strain where smooth muscle was present only in the lowermost portion adjoining the stomach. Ultrastructural studies of the oesophageal wall from 5- and 10-day-old ICRC mice revealed an apparently normal muscle coat. In 3-month-old ICRC mice the upper abdominal segment of the oesophagus showed several abnormalities of smooth muscle fibres and paucity of plexus tissue accompanied by interstitial collagen deposition. The abnormalities were more severe in 1-year-old animals and were seen throughout the abdominal segment. From this study it is suggested that the primary cause of megaoesophagus in ICRC mice is neurogenic and not myogenic.     

Pterostilbene induces apoptosis in hepatocellular carcinoma cells: Biochemical,pathological, and molecular markers

Worldwide, hepatocellular carcinoma (HCC) is considered the sixth most prevalent cancer and ranked third in causes leading to death. Pterostilbene (PTE), a dimethylated analog of resveratrol, is a phytochemical found in fruits such as blueberries and grapes, and is known for its anticancer effect. The current study intended to investigate the effect of PTE on HepG2 cells. Cell viability, colony-forming potential, lipid peroxidation, catalase enzyme (CAT), superoxide dismutase (SOD), and caspase 3 activities, histone release, and expression levels of mTOR, S6K1, p53, and STAT3 proteins were assessed in PTE-treated HepG2 cells. In addition, the cellular and ultrastructural alterations were evaluated by light and transmission electron microscopy. PTE induced a significant reduction in HepG2 viability in a dose-dependent manner (IC₅₀ of PTE = 74 ± 6 μM), accompanied by a decrease in colony formation potential. PTE-treated cancer cells exhibited a decrease in lipid peroxidation and CAT activity, and an increase in histone release, caspase-3, and SOD activities. Ultrastructurally, PTE-treated cells exhibited notable cell shrinkage, reduced number of filopodia, increased vacuolization, apoptotic bodies, accumulation of lipid droplets, enlarged mitochondria, dilated endoplasmic reticulum, pyknotic nuclei, and cellular fragmentation. mTOR, S6K1, and STAT3 levels were downregulated, however p53 level was modulated in PTE-treated cells. The anticancer potential of PTE might be related to its ability to alter the ultrastructure morphology, reduce mitotic activity, and modulate some key protein required for cell proliferation, suggesting its potential to trigger cancer cells towards apoptosis.     

Lipid bodies in coral-dinoflagellate endosymbiosis: proteomic and ultrastructural studies

Gastrodermal lipid bodies (LBs) are organelles involved in the regulation of the mutualistic endosymbiosis between reef‐building corals and their dinoflagellate endosymbionts (genus Symbiodinium). As their molecular composition remains poorly defined, we herein describe the first gastrodermal LB proteome and examine in situ morphology of LBs in order to provide insight into their structure and function. After tissue separation of the tentacles of the stony coral Euphyllia glabrescens, buoyant LBs of the gastroderm encompassing a variety of sizes (0.5–4 μm in diameter) were isolated after two cycles of subcellular fractionation via stepwise sucrose gradient ultracentrifugation and detergent washing. The purity of the isolated LBs was demonstrated by their high degree of lipid enrichment and as well as the absence of contaminating proteins of the host cell and Symbiodinium. LB‐associated proteins were then purified, subjected to SDS‐PAGE, and identified by MS using an LC‐nano‐ESI‐MS/MS. A total of 42 proteins were identified within eight functional groups, including metabolism, intracellular trafficking, the stress response/molecular modification and development. Ultrastructural analyses of LBs in situ showed that they exhibit defined morphological characteristics, including a high‐electron density resulting from a distinct lipid composition from that of the lipid droplets of mammalian cells. Coral LBs were also characterized by the presence of numerous electron‐transparent inclusions of unknown origin and composition. Both proteomic and ultrastructural observations seem to suggest that both Symbiodinium and host organelles, such as the ER, are involved in LB biogenesis.     

Testing and validating a modified CTAB DNA extraction method to enable molecular parentage analysis of fertilized eggs and larvae of an emerging South African aquaculture species,the dusky kob Argyrosomus japonicus

This study describes the successful implementation of a modified cetyltrimethyl ammonium bromide (CTAB) protocol to isolate genomic DNA and amplify 14 microsatellite markers from fertilized eggs and larvae of an emerging South African farmed marine fish species, the dusky kob Argyrosomus japonicus. To test and validate the efficiency of this method, genetic data were utilized to resolve parentage and kinship of first‐generation (F1) offspring produced in mass‐spawning events of wild broodstock fish in a commercial hatchery.     

Experimental candidal mastitis in goats: Clinical,haematological, biochemical and sequential pathological studies

The present study, first of its kind, was conducted with the objectives to understand hitherto little known aspects of candidal mastitis, like its sequential pathology, pathogenesis and clinico-biochemical changes. For this purpose, unilateral intramammary inoculation of 10 goats with Candida albicans (1.2 × 10⁷ yeast cells) resulted in the development of mastitis, with gross and microscopic lesions being restricted to the infected udder halves only and without dissemination of infection to the opposite uninfected udder halves as well as other organs of the body. The experiment was continued for 40 days and after infection, there was sharp fall in milk yield and Candida albicans was directly demonstrated in the milk and re-isolated from the milk and udder tissues up to 30th day after inoculation. An increase in total immunoglobulins in the milk and plasma along with increase in total plasma proteins were also observed. Haematology revealed leukocytosis and neutrophilia. Microscopically, there was acute purulent mastitis, which later became chronic, nonpurulent and interstitial with formation of granulomas. It was concluded that Candida albicans was highly pathogenic to the lactating goat mammary gland even without immunosuppression or antibiotic treatment, resulting in severe irreversible tissue damage and nearly complete agalactia. This revised version was published online in August 2006 with corrections to the Cover Date.     

Trypanosoma cruzi: ultrastructural, cytochemical and freeze-fracture studies of protein uptake.

Epimastigotes and trypomastigotes of Trypanosoma cruzi, obtained from liquid cultures, have vesicles and multivesicular structures in their cytoplasm. Horseradish peroxidase (HRP) was used as a tracer to study the uptake of protein by these two forms. In epimastogotes HRP is ingested by a process of pinocytosis which occurs through the cytostome. Trypomastigotes do not have a cytostome, and pinocytosis occurs through the flagellar pocket region. The pinocytotic vesicles can fuse with each other to form large multivesicular structures that are more abundant in epimastigotes than in trypomastigotes. The cell membrane as well as the membranes of the pinocytotic vesicles and the large multivesicular structure have carbohydrates, as detected by the periodic acid-thiosemicarbazide-silver proteinate technique. Intramembranous particles were observed by using the freeze-fracture technique. The cell membrane has many particles, whereas the membranes of the vesicles and multivesicular structure have few or no particles.