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Julian Lombardi - One of the best experts on this subject based on the ideXlab platform.
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nmr studies of glucose and alanine utilization and maternal embryonic nutrient transfer in the smooth dogfish Mustelus canis
Comparative Biochemistry and Physiology Part A: Physiology, 1995Co-Authors: Charles R Graham, Calhoun Bond, V P Chacko, Julian LombardiAbstract:Abstract Captive dogfish, Mustelus canis, were injected with saline containing 13C-enriched alanine or glucose and permitted to metabolize labeled substrates. Blood plasma and other body fluids were analyzed using high field 13C nuclear magnetic resonance (NMR) spectroscopy. Both injected glucose and alanine are converted to lactate with alanine conversion more rapid than that of glucose. 13C-enriched alanine and lactate appear in intracapsular fluids after injection of 13C-enriched alanine into the maternal blood vascular system. Studies involving the injection of 13C-enriched nutrients into the maternal circulation can yield information on metabolite utilization and embryonic nutrition in viviparous matrotrophs.
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microdetermination of dry mass content in the uterine fluid of four species of viviparous sharks squalus acanthias carcharhinus plumbeus Mustelus canis and rhizoprionodon terraenovae
Comparative Biochemistry and Physiology Part A: Physiology, 1994Co-Authors: Brian D Strahl, Julian LombardiAbstract:We describe a micromethod for the determination of dry mass content and wet weight in small (⩾ 20 μl) samples of shark uterine (periembryonic) fluid using a volumetric micropipette and electrobalance. Periembryonic fluid and maternal blood plasma from pregnant specimens of the viviparous sharks Squalus acanthias, Carcharhinus plumbeus, Mustelus canis and Rhizoprionodon terraenovae were analyzed for dry mass content. Values for dry mass (mg/ml), fluid density (g/ml) and percent dry mass are calculated for the periembryonic fluids and maternal blood plasmas of each species. These results are discussed in relation to the dry mass content of periembryonic fluids in other viviparous sharks.
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Egg capsule structure and permeability in the viviparous shark, Mustelus canis
Journal of Experimental Zoology, 1993Co-Authors: Julian Lombardi, Tamarah FilesAbstract:The structure and permeability characteristics of egg capsules of the viviparous matrotrophic elasmobranch Mustelus canis were investigated by scanning electron microscopy (SEM), X-ray microprobe elemental analysis, and through the use of modified Ussing chambers. The egg capsule surrounds the developing embryo during gestation and consists of a four or more orthogonally arranged laminae of fibrous material. SEM and energy dispersive spectroscopy (EDS) of inner and outer capsular surfaces reveal that the capsule is 4.7 μm in thickness and possesses scattered calcium deposits along its inner and outer surfaces. Transcapsular permeability studies qualitatively demonstrate that capsules are readily permeable to fast green fcf (808 Da) and rose bengal (1,000 Da). Capsules are impermeable to insulin (5, 750 Da), lysozyme (14,300 Da) and bovine albumin (66,000Da). Glucose (P= 3.3 × 10−4 ± 1.2 × 10−4cm/sec[n = 120])and urea(P= 4.5 × 10−4 ± 2.3 × 10−4cm/sec [n = 139]) readily pass across the egg capsules. It is suggested that maternal-embryonic nutrient transfer primarily involves the transcapsualr passage of low (
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egg capsule structure and permeability in the viviparous shark Mustelus canis
Journal of Experimental Zoology, 1993Co-Authors: Julian Lombardi, Tamarah FilesAbstract:The structure and permeability characteristics of egg capsules of the viviparous matrotrophic elasmobranch Mustelus canis were investigated by scanning electron microscopy (SEM), X-ray microprobe elemental analysis, and through the use of modified Ussing chambers. The egg capsule surrounds the developing embryo during gestation and consists of a four or more orthogonally arranged laminae of fibrous material. SEM and energy dispersive spectroscopy (EDS) of inner and outer capsular surfaces reveal that the capsule is 4.7 μm in thickness and possesses scattered calcium deposits along its inner and outer surfaces. Transcapsular permeability studies qualitatively demonstrate that capsules are readily permeable to fast green fcf (808 Da) and rose bengal (1,000 Da). Capsules are impermeable to insulin (5, 750 Da), lysozyme (14,300 Da) and bovine albumin (66,000Da). Glucose (P= 3.3 × 10−4 ± 1.2 × 10−4cm/sec[n = 120])and urea(P= 4.5 × 10−4 ± 2.3 × 10−4cm/sec [n = 139]) readily pass across the egg capsules. It is suggested that maternal-embryonic nutrient transfer primarily involves the transcapsualr passage of low (<5 kDa) molecualr weight components. These data are discussed in relation to the mechanisms of placental attachment in matrotrophic sharks. © 1993 Wiley-Liss, Inc.
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chemical composition of uterine fluid in four species of viviparous sharks squalus acanthias carcharhinus plumbeus Mustelus canis and rhizoprionodon terraenovae
Comparative Biochemistry and Physiology Part A: Physiology, 1993Co-Authors: Julian Lombardi, Kelly B Jones, Catharine A Garrity, Tamarah FilesAbstract:Abstract 1. 1. Uterine fluid and blood plasma samples from pregnant specimens of the viviparous sharks Squalus acanthias, Carcharhinus plumbeus, Mustelus canis and Rhizoprionodon lerraenovae were analysed for total protein, total lipid, total glucose and osmolarity. 2. 2. Intracapsular uterine fluids of the matrotroph, Rhizoprionodon terraenovae , whose embryos bear appendiculae, exhibit higher concentrations of protein, lipid and glucose than those of placenta! matrotrophs lacking appendiculae. 3. 3. In near-term specimens R. terraenovae , intracapsular protein and lipid levels in excess of those within the maternal blood plasma suggest active concentration of these molecules within intracapsular fluids. 4. 4. There exists a significant osmotic differential between maternal blood plasma and intracapsular uterine fluid in both R. terraenovae and M. canis . 5. 5. These results are discussed in relation to the evolution of maternal-embryonic transfer mechanisms in viviparous sharks.
William C Hamlett - One of the best experts on this subject based on the ideXlab platform.
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the interleukin 1 il 1 system in the uteroplacental complex of a cartilaginous fish the smoothhound shark Mustelus canis
Reproductive Biology and Endocrinology, 2003Co-Authors: Chiara Cateni, L Paulesu, Elisa Bigliardi, William C HamlettAbstract:Cartilaginous fish are the oldest extant jawed vertebrates and the oldest line to have placentae. Their pivotal evolutionary position makes them attractive models to investigate the mechanisms involved in the maternal-fetal interaction. This study describes the tissue expression of the cytokine interlukin-1 (IL-1) α, IL-1 β and its specific membrane receptor, IL-1 receptor type I (IL-1R tI) in a placental cartilaginous fish, the smoothhound shark, Mustelus canis. The presence of this cytokine has been reported in many mammalian placentae, as well as in the placenta of a squamate reptile and this study extends these observations to the cartilaginous fishes. The uteroplacental complex in M. canis consists of a yolk sac modified into a functional yolk sac placenta and complimentary uterine attachment sites. Immunohistochemistry for IL-1 α, IL-1 β and the receptor reveals leucocytes of both the mother and fetus to be positive, as well as the apical aspect of paraplacental cells and the apical vesicles in the umbilical cord epithelium. Yolk sac endoderm is also positive with all the stains while the ectoderm is positive only for IL-1 α. Immunoreactivity in the uterine epithelium was obtained for IL-1 α and the receptor. The egg envelope is always negative. In light of the recent finding of IL-1 β gene in a cartilaginous fish and of the high level of conservation of proteins implicated in IL-1 action, our data suggest that IL-1 system is a key mediator of the materno-fetal interaction since the oldest extant placental vertebrates.
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uterine epithelial sperm interaction endometrial cycle and sperm storage in the terminal zone of the oviducal gland in the placental smoothhound Mustelus canis
Journal of Experimental Zoology, 2002Co-Authors: William C Hamlett, John A Musick, Christopher K Hysell, David M SeverAbstract:The fate of spermatozoa deposited within the female reproductive tract has been described in the smoothhound, Mustelus canis. Evidence of uterine epithelial-sperm interaction is presented, as well as documentation of sperm storage specifically in the terminal zone of the oviducal gland. Sperm fate is correlated with morphology of the endometrial cycle and specificity of storage in the oviducal gland. The endometrium of M. canis undergoes dramatic tissue remodeling associated with gestation. In females harboring fertilized ova or preimplantation yolk-reliant embryos, the uterine epithelium is simple cuboidal with mucous droplets for lubrication. The presence of the embryo elicits a response from the uterus, which becomes modified for nutrient and respiratory exchange into vascular uterine attachment sites that abut the distal aspect of the yolk sac. Areas of the uterus adjacent to the uterine attachment sites are termed paraplacental sites. Uterine attachment sites are simple squamous while the paraplacental epithelium is simple columnar. Paraplacental cells have basal metachromatic vesicles and a dense array of apical cytoplasmic filaments. Immediately postpartum the uterine attachment sites, now termed uterine or placental scars, begin to remodel to a mucous epithelium for the next gestational cycle. Paraplacental cells slough off the apical filamentous portion, and sperm become embedded in the epithelium. Bundled sperm occur throughout gestation in the terminal zone of the oviducal gland. Sperm are not embedded in the terminal zone epithelium as in the uterus. Following sperm release from the uterus, the paraplacental epithelium reverts to a mucous epithelium for the next reproductive cycle. Fertilization is presumed to occur in the anterior oviduct above the oviducal gland. The physiological mechanisms that mediate sperm-uterus attachment, release, and storage in the terminal zone of the oviducal gland are currently under investigation.
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Uterine epithelial‐sperm interaction, endometrial cycle and sperm storage in the terminal zone of the oviducal gland in the placental smoothhound, Mustelus canis
Journal of Experimental Zoology, 2001Co-Authors: William C Hamlett, John A Musick, Christopher K Hysell, David M SeverAbstract:The fate of spermatozoa deposited within the female reproductive tract has been described in the smoothhound, Mustelus canis. Evidence of uterine epithelial-sperm interaction is presented, as well as documentation of sperm storage specifically in the terminal zone of the oviducal gland. Sperm fate is correlated with morphology of the endometrial cycle and specificity of storage in the oviducal gland. The endometrium of M. canis undergoes dramatic tissue remodeling associated with gestation. In females harboring fertilized ova or preimplantation yolk-reliant embryos, the uterine epithelium is simple cuboidal with mucous droplets for lubrication. The presence of the embryo elicits a response from the uterus, which becomes modified for nutrient and respiratory exchange into vascular uterine attachment sites that abut the distal aspect of the yolk sac. Areas of the uterus adjacent to the uterine attachment sites are termed paraplacental sites. Uterine attachment sites are simple squamous while the paraplacental epithelium is simple columnar. Paraplacental cells have basal metachromatic vesicles and a dense array of apical cytoplasmic filaments. Immediately postpartum the uterine attachment sites, now termed uterine or placental scars, begin to remodel to a mucous epithelium for the next gestational cycle. Paraplacental cells slough off the apical filamentous portion, and sperm become embedded in the epithelium. Bundled sperm occur throughout gestation in the terminal zone of the oviducal gland. Sperm are not embedded in the terminal zone epithelium as in the uterus. Following sperm release from the uterus, the paraplacental epithelium reverts to a mucous epithelium for the next reproductive cycle. Fertilization is presumed to occur in the anterior oviduct above the oviducal gland. The physiological mechanisms that mediate sperm-uterus attachment, release, and storage in the terminal zone of the oviducal gland are currently under investigation.
Tamarah Files - One of the best experts on this subject based on the ideXlab platform.
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Egg capsule structure and permeability in the viviparous shark, Mustelus canis
Journal of Experimental Zoology, 1993Co-Authors: Julian Lombardi, Tamarah FilesAbstract:The structure and permeability characteristics of egg capsules of the viviparous matrotrophic elasmobranch Mustelus canis were investigated by scanning electron microscopy (SEM), X-ray microprobe elemental analysis, and through the use of modified Ussing chambers. The egg capsule surrounds the developing embryo during gestation and consists of a four or more orthogonally arranged laminae of fibrous material. SEM and energy dispersive spectroscopy (EDS) of inner and outer capsular surfaces reveal that the capsule is 4.7 μm in thickness and possesses scattered calcium deposits along its inner and outer surfaces. Transcapsular permeability studies qualitatively demonstrate that capsules are readily permeable to fast green fcf (808 Da) and rose bengal (1,000 Da). Capsules are impermeable to insulin (5, 750 Da), lysozyme (14,300 Da) and bovine albumin (66,000Da). Glucose (P= 3.3 × 10−4 ± 1.2 × 10−4cm/sec[n = 120])and urea(P= 4.5 × 10−4 ± 2.3 × 10−4cm/sec [n = 139]) readily pass across the egg capsules. It is suggested that maternal-embryonic nutrient transfer primarily involves the transcapsualr passage of low (
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egg capsule structure and permeability in the viviparous shark Mustelus canis
Journal of Experimental Zoology, 1993Co-Authors: Julian Lombardi, Tamarah FilesAbstract:The structure and permeability characteristics of egg capsules of the viviparous matrotrophic elasmobranch Mustelus canis were investigated by scanning electron microscopy (SEM), X-ray microprobe elemental analysis, and through the use of modified Ussing chambers. The egg capsule surrounds the developing embryo during gestation and consists of a four or more orthogonally arranged laminae of fibrous material. SEM and energy dispersive spectroscopy (EDS) of inner and outer capsular surfaces reveal that the capsule is 4.7 μm in thickness and possesses scattered calcium deposits along its inner and outer surfaces. Transcapsular permeability studies qualitatively demonstrate that capsules are readily permeable to fast green fcf (808 Da) and rose bengal (1,000 Da). Capsules are impermeable to insulin (5, 750 Da), lysozyme (14,300 Da) and bovine albumin (66,000Da). Glucose (P= 3.3 × 10−4 ± 1.2 × 10−4cm/sec[n = 120])and urea(P= 4.5 × 10−4 ± 2.3 × 10−4cm/sec [n = 139]) readily pass across the egg capsules. It is suggested that maternal-embryonic nutrient transfer primarily involves the transcapsualr passage of low (<5 kDa) molecualr weight components. These data are discussed in relation to the mechanisms of placental attachment in matrotrophic sharks. © 1993 Wiley-Liss, Inc.
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chemical composition of uterine fluid in four species of viviparous sharks squalus acanthias carcharhinus plumbeus Mustelus canis and rhizoprionodon terraenovae
Comparative Biochemistry and Physiology Part A: Physiology, 1993Co-Authors: Julian Lombardi, Kelly B Jones, Catharine A Garrity, Tamarah FilesAbstract:Abstract 1. 1. Uterine fluid and blood plasma samples from pregnant specimens of the viviparous sharks Squalus acanthias, Carcharhinus plumbeus, Mustelus canis and Rhizoprionodon lerraenovae were analysed for total protein, total lipid, total glucose and osmolarity. 2. 2. Intracapsular uterine fluids of the matrotroph, Rhizoprionodon terraenovae , whose embryos bear appendiculae, exhibit higher concentrations of protein, lipid and glucose than those of placenta! matrotrophs lacking appendiculae. 3. 3. In near-term specimens R. terraenovae , intracapsular protein and lipid levels in excess of those within the maternal blood plasma suggest active concentration of these molecules within intracapsular fluids. 4. 4. There exists a significant osmotic differential between maternal blood plasma and intracapsular uterine fluid in both R. terraenovae and M. canis . 5. 5. These results are discussed in relation to the evolution of maternal-embryonic transfer mechanisms in viviparous sharks.
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free amino acids in the uterine fluids of four species of viviparous sharks squalus acanthias carcharhinus plumbeus Mustelus canis and rhizoprionodon terraenovae
Comparative Biochemistry and Physiology B, 1993Co-Authors: Tamarah Files, Julian LombardiAbstract:Abstract 1. 1. Uterine fluid and blood plasma samples from pregnant specimens of the viviparous sharks Squalus acanthias, Carcharhinus plumbeus, Mustelus canis and Rhizoprionodon terraenovae were subjected to analysis of free amino acids by high-pressure liquid chromatography. 2. 2. Intracapsular uterine fluid of the matrotroph, Rhizoprionodon terraenovae , whose embryos bear appendiculae, is rich in taurine, glutamate, valine, nor-leucine and phenylalanine and exhibits higher concentrations of all amino acids than the uterine fluids of placental matrotrophs lacking appendiculae. 3. 3. Results are discussed in relation to the evolution of maternal-embryonic transfer mechanisms in viviparous sharks.
K S Chung - One of the best experts on this subject based on the ideXlab platform.
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evaluacion del crecimiento instantaneo de juveniles del tiburon viuda virma Mustelus canis en su habitat natural a traves del indice arn adn
Ciencias Marinas, 2006Co-Authors: Raquel Tavares, Mairin Lemus, K S ChungAbstract:The RNA/DNA and protein/DNA ratios were evaluated to determine the physiological condition of the smooth dogfish shark (Mustelus canis) in its natural habit...
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evaluacion del crecimiento instantaneo de juveniles del tiburon viuda virma Mustelus canis en su habitat natural a traves del indice arn adn evaluation of the instantaneous growth of juvenile smooth dogfish sharks Mustelus canis in their natural habi
2006Co-Authors: Raquel Tavares, Mairin Lemus, K S ChungAbstract:The RNA/DNA and protein/DNA ratios were evaluated to determine the physiological condition of the smooth dogfish shark (Mustelus canis) in its natural habitat. The samples were collected from animals captured by the Venezuelan trawling fleet operating between the north coast of Sucre State and Margarita Island. Proteins (Bradford method) and nucleic acids (fluorometric method) were quantified from muscle tissue samples. Instantaneous growth was estimated from the RNA/DNA and protein/DNA relationships. A decrease in the RNA/DNA ratio was observed in relation to body length in both sexes. In the case of the protein/DNA ratio, the distribution values do not show any tendency relative to body length or sex. The results show that the RNA/DNA ratio can be used to analyze the instantaneous growth and population health of sharks.
S Frasca - One of the best experts on this subject based on the ideXlab platform.
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naturally occurring lesions and micro organisms in two species of free living sharks the spiny dogfish squalus acanthias l and the smooth dogfish Mustelus canis mitchill from the north western atlantic
Journal of Fish Diseases, 2002Co-Authors: J D Borucinska, S FrascaAbstract:Twenty-three smooth dogfish, Mustelus canis L., and 20 spiny dogfish, Squalus acanthias (Mitchill), were examined for the presence of diseases. Sharks were collected from the north-western Atlantic between April and September 2000. Major organs were sampled for histopathology and bacterial cultures were taken from kidneys. Macroscopic lesions were infrequent and included intestinal cestodiasis and gastric and dermal erosions. Microscopic lesions were common in both shark species. Mustelus canis had numerous degenerative lesions involving the pancreatic ducts, seminiferous tubules and coronary vessels. The most frequent lesions in S. acanthias were parasitic and included pancreatic nematodiasis and biliary myxosporeosis. Additionally, both species had focal meningitis, encephalitis, dermatitis, gastritis, enteritis and glomerulomesangial thickening. Microscopic parasites included intestinal coccidiosis, unclassified gastric and testicular protozoa, skeletal muscle and renal tubular myxosporeans, a branchial trichodinid ciliate, olfactory and branchial trematodes, gastrointestinal cestodes and larval nematodes. Shewanella putrefaciens, Photobacterium sp., Vibrio sp., Pseudomonas sp. and Alteromonas sp. were isolated from kidneys of nine sharks. The role of the above lesions in the natural mortality and morbidity of the two shark species is unknown. The finding that apparently healthy sharks can harbour potentially debilitating lesions warrants the inclusion of histopathological studies in the management and conservation of sharks.
