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Many shark populations are in danger of extinction as a direct result of man's activities. A change in attitude and a greater understanding of species' requirements are needed to prevent further destruction and replenish numbers, thus sustaining trade, fisheries and sport activity.
One month keeping of rats on a diet with 23% fat extracted from a polar shark liver, causes not sharply pronounced fatty infiltration of liver, a moderate hyperplasia of spleen lymphoid tissue as well as its plasmatization and an increase of megakaryocytes, the predecessors of thrombocyte cells, in it.
A rapid microwave-assisted digestion and derivatization method for the determination of fatty acids in shark cartilage by GC-MS was developed. The optimum conditions for digestion and derivatization were studied in detail using orthogonal design. The digestion and derivatization were accomplished in 4 minutes at 600 W microwave power using HCl-methanol (1:4, V/V) as digestion and derivatization solvent, and the extraction of the target analytes could be carried out simultaneously. This method is rapid, solvent-saving, and particularly suitable for the rapid determination of fatty acids in solid samples.
See fish oils affect different systemic reactions innate immunity including. Innate immunity is responsible for immediate pathogen recognition and inactivation. Innate immunity decides also on the type of required immunity development. In the presented paper we have proved that supportive treatment with shark oil components normalize complement level, natural killer cells activity and reactive oxygen intermediates production by peripheral blood leukocytes of peoples suffering from active form rheumatoid arthritis.
The 18S rRNA sequence was determined for two teleostean fish species, Fundulus heteroclitus and Sebastolobus altivelis, and two sharks, Squalus acanthias and Echinorhinus cookei. To study the molecular phylogeny of these taxa, the sequences were compared with 18S rRNA sequences of the Coelacanth Latimeria chalumnae, the frog Xenopus laevis, and humans. Maximum parsimony analysis of the sequences resulted in a single most parsimonious tree that is in agreement with the expected phylogeny. The correct phylogenetic tree was also found when using S. altivelis alone as the teleost representative. In contrast, the most parsimonious tree found by using F. heteroclitus as the teleost representative presented anomalous groupings (the teleost branch being grouped with humans), matching results previously obtained. However, a bootstrap analysis showed that some branches containing anomalous relationships were not significantly supported. An explanation for this peculiarity, the differences between our tree and previously identified ones, and their phylogenetic implications are discussed.
AIM: To investigate the protective effects of shark hepatic stimulator substance (sHSS) against acute hepatic injury induced by acetaminophen (AAP) in mice. METHODS: Acute hepatic injury model of Balb/c mice was induced by a single intraperitoneal injection of AAP (200 mg.kg-1, i.p.). Serum ALT and AST activities were analyzed. The changes of microstructure and ultrastructure of hepatocyte were observed under optical and electronic microscope. The hepatocyte apoptosis was analyzed by flow cytometer and the expression level of Fas mRNA was determined by RT-PCR. RESULTS: The activities of serum ALT and AST were significantly decreased and both necrosis and inflammatory infiltration were improved in the mice treated with sHSS 3.0 and 1.5 mg.kg-1. sHSS (3.0 mg.kg-1) prevented the ultrastructural changes of hepatocytes caused by AAP, decreased the percentage of apoptotic cells, and downregulated the expression level of Fas mRNA. CONCLUSION: sHSS protected hepatocytes from AAP-induced injury, which might be associated with its protection of the mitochondria and inhibition of apoptosis and expression of Fas mRNA in hepatocytes.
Shark cartilage proteoglycans bear predominantly chondroitin 6-sulfate. After exhaustive protease digestion, reductive beta-elimination, and subsequent chondroitinase ABC digestion, 13 hexasaccharide alditols, which are nonsulfated, sulfated, and/or phosphorylated, were obtained from the carbohydrate-protein linkage region. Six compounds, containing 0 or 1 sulfate and/or phosphate residue, represent approximately 40% of the isolated linkage hexasaccharide alditols. They were analyzed by chondroitinase ACII or alkaline phosphatase digestion in conjunction with high performance liquid chromatography, and by 500 MHz one- and two-dimensional 1H NMR spectroscopy. All six compounds have the conventional structure in common. Delta 4,5-GlcA beta 1-3GalNAc beta 1-4GlcA beta 1-3Gal beta 1-3Gal beta 1-4Xyl-ol One compound has no sulfate nor phosphate. Two of the monosulfated compounds have a O-sulfate on C-6 or on C-4 of the GalNAc residue. The third monosulfated compound has a novel O-sulfate on C-6 of the Gal residue attached to xylitol. The two phosphorylated compounds have O-phosphate on C-2 of Xyl-ol, and one of them has in addition sulfate on C-6 of GalNAc.
Shark cartilage proteoglycans bear predominantly chondroitin 6-sulfate. After exhaustive protease digestion, reductive beta-elimination and subsequent chondroitinase ABC digestion, 13 hexasaccharide alditols were obtained from the carbohydrate-protein linkage region and six of them contain 0 or 1 sulfate and/or 1 phosphate residue (Sugahara, K., Ohi, Y., Harada, T., de Waard, P., and Vliegenthart, J. F. G. (1992) J. Biol. Chem. 267, 6027-6035). The other seven compounds, which represent approximately 60% of the isolated linkage hexasaccharides, were analyzed by chondroitinase ACII digestion in conjunction with high performance liquid chromatography and by 500-MHz one- and two dimensional 1H NMR spectroscopy. All seven compounds have the following conventional structure in common. [formula: see text] Two disulfated compounds have an O-sulfate on C-6 of the Gal-2 residue attached to xylitol in combination with an O-sulfate on C-4 or on C-6 of the GalNAc residue. The third disulfated compound has O-sulfate on C-6 of Gal-2, and also on C-6 of Gal-3. Two of the trisulfated compounds also have O-sulfate on C-6 of both Gal-2 and Gal-3 with in addition sulfate on C-6 or C-4 of GalNAc. The other two trisulfated compounds have O-sulfate on C-6 of Gal-2 and on C-4 of Gal-3 in conjunction with sulfate on C-6 or C-4 of GalNAc.
The ability of activity modulators of ornithine transcarbamoylase (OCT) from the liver of the thresher shark Alopias vulpinus to stabilize the enzyme against thermal denaturation was investigated in the tri-buffer at pH 7.8, at temperatures ranging from 60 to 70 (o)C, in the presence of polyhydroxylic molecules such as glycerol and sugars. The study indicated that in the presence of 0.5 M sugars and 1.6 M glycerol in the preincubation medium the OCT activity increases. When trehalose is introduced directly in the reaction mixture in a range of concentration of 0.25-0.5 M, the activity is lower than that with maltose, glycerol and buffer alone. Kinetic data for carbamoyl phosphate and ornithine with and without maltose and glycerol are similar, whereas trehalose increases the kinetic values. Arrhenius plots show an increase of activation energy due to trehalose, whereas values obtained with maltose and glycerol are similar to the control.
The blacknose shark, Carcharhinus acronotus, is a viviparous anamniote that develops an epitheliochorial yolk sac placenta. The fetal portion of the uteroplacental complex consists of a proximal portion that forms saccular evaginations. The cells are bilayered stratified squamous with surface microvilli and a high concentration of cytoplasmic filaments. The tertiary egg envelope intervenes between the distal portion of the placenta and uterus. It has delaminations on the uterine surface and is compacted on the placental surface. The uterine epithelium is cuboidal to columnar and is characterized by prominent RER, Golgi, and secretion vesicles. The capillary endothelium is continuous. Nutrient and respiratory exchange is effected between the uterus and distal portion of the yolk sac. The distal portion of the placenta is a bilayer. An elaborate array, of microvilli forms an interface with the egg envelope. Dense non-membrane bound granules occur in the interspace between the egg envelope and the distal placenta. This material, presumably of uterine origin, is endocytosed in smooth-walled vesicles of the placental cells. The endothelium of the capillaries is fenestrated.
Investigation of a number of shark attacks in South Australian waters has lead to recognition of pattern similarities on equipment recovered from the scene of such attacks. Six cases are presented in which a common pattern of striations has been noted.
The therapeutic effect of a Polar shark cartilage preparation which is an enzymatic hydrolysate was studied in a rabbit model of infective allergic pseudotuberculous arthritis. Characterization of the chemical composition of the preparation designed by an original method is presented. Improvement of the general state of the affected joints and development of tissue immunomorphological responses were shown.
Fish oils are the source of nutrients important for health maintenance. The most significant are essential fatty acids (EFA) of n-3 family, alkylglycerols and squalene. N-3 EFA are of great importance in atherosclerosis prevention. Alkylglycerols and squalene are modulators of immunity to infections and cancer. Shark liver oil contains great amounts of alkylglycerols and squalene, and moderate of n-3 EFA. Therefore, it is used as an adjunctive agent in cancer therapy, especially in radiotherapy, and in the treatment of infectious diseases.
We present a case of multiple lacerations occurring from an encounter with a bull shark in which violent contact was made with the animal's rough skin. Conservative treatment of the injury resulted in good clinical outcome without any complications. Such events are only rarely reported in the medical literature.
Lockenloia sanguinis n. gen., n. sp. (Nematoda: Dracunculoidea) is described from fragments collected in the atrium of the heart of a male nurse shark, Ginglymostoma cirratum (Bonnaterre). The new genus is distinguished by its reduced buccal capsule; body that expands abruptly just behind the cephalic extremity; long and undivided esophagus; and subconical, pointed tail. Until the systematics of the superfamily are revised, the familial placement of the taxon is unclear.
The influence of buffer, pH, Mg2+, ATP, Na+, K+ and temperature on the extent and rate of aminoacyl-tRNA synthesis was studied with the shark Mustelus mento liver tRNAs and aminoacyl-tRNA synthetases. The optimum pH for the aminoacylation of tRNAMet was 8.3 and for tRNAVal 7.0. For these two tRNAs the Mg2+ optimum was related to the levels of ATP required and to the pH of the reactions. It is suggested that the Mg2+ concentration required for each aminoacylation system reflects the true conditions under which the substrate for the enzyme, the MgATP2- complex, is formed. The effect of monovalent cations was also examined. Val-tRNA synthesis was slightly stimulated up to a concentration of 50 mM NaCl (KCl). Over 100 mM salt, a rapid inhibition was observed. Met-tRNA synthesis behaves differently by being stimulated over a wide range of salt concentrations.
Calliobothrium pritchardae n. sp. is described from the whiskery shark, Furgaleus macki (Whitley, 1943), collected from Young Rocks in South Australia. This species differs from the 7 other known species of Calliobothrium in its possession of 2 rather than 3 posthook loculi. It is a further distinguished from all other Calliobothrium species except Calliobothrium evani in its possession of asymmetrical hooks. The lack of an accessory piece between the bases of the axial hooks and medial axial hook bases that are longer than the lateral axial hook bases further distinguish the new species from C. evani in which an accessory piece is present and the relative lengths of the medial and lateral axial hook bases are reversed. Scanning electron microscopy reveals spiniform microtriches on the neck and proximal bothridial surfaces, filiform microtriches on the apical bothridial surfaces, and a combination of the 2 microthrix types on the distal bothridial surfaces. The extended bases of the axial hooks are densely covered with spiniform microtriches. In addition, the number of testes within worms decreases substantially in progressively posterior (older) segments. The generic diagnosis of Calliobothrium is emended to include this species with 2 rather than 3 posthook loculi.
The existence of the surface-connected canalicular system has been demonstrated ultrastructurally in shark [Triakis scyllia) thrombocytes using the ruthenium red method to fix and stain the glycocalyx. In ultrathin sections fixed routinely in glutaraldehyde followed by osmium tetroxide, numbers of electron-lucent vesicles are distributed throughout the cytoplasm. Since ruthenium red-positive reaction product is deposited on the inner surface of these vesicles, they are defined as the surface-connected canalicular system. Moreover, the semithin sectioned thrombocytes fixed by the ruthenium red method provide evidence that the surface-connected system is not composed of vesicles but also of numerous canaliculi. These results suggest that the surface-connected canalicular system is one of the most basic organelles of the thrombocyte system, common to submammalian species and to mammals.