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Comparative study of shark (Carcharinus falciformis) and mammalian (Mesocricetus auratus) cells exposed to chemical carcinogens
Title
Comparative study of shark (Carcharinus falciformis) and mammalian (Mesocricetus auratus) cells exposed to chemical carcinogens.
Creator
Ritchey, Donna Mae., Florida Atlantic University, Hartmann, James X.
Abstract/Description
It is not known by what mechanism members of the subclass Elasmobranchii derive their natural resistance to neoplasia. To determine if this resistance is at the cellular level, cultures of shark (Carcharinus falciformis) cells were exposed to varying concentrations of the chemical carcinogens methanesulfonic acid ethyl ester (EMS) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Treated cells were assayed for cytotoxicity, formation of transformed foci and growth in agarose. It was found that...
Show moreIt is not known by what mechanism members of the subclass Elasmobranchii derive their natural resistance to neoplasia. To determine if this resistance is at the cellular level, cultures of shark (Carcharinus falciformis) cells were exposed to varying concentrations of the chemical carcinogens methanesulfonic acid ethyl ester (EMS) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Treated cells were assayed for cytotoxicity, formation of transformed foci and growth in agarose. It was found that a greater chemical concentration was necessary to reach LC50 in shark cells than in mammalian cells (BHK21 Cl13). Shark cell cultures developed no transformed foci over a range of chemical concentrations of EMS whereas foci formed at all concentrations in BHK control cultures exposed to EMS. Treated shark cells did not develop transformed colonies in agarose, but the mammalian cells readily formed colonies. These results suggest that the natural resistance of elasmobranchs to neoplasia could be partially, if not entirely, regulated at the cellular level.
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Date Issued
1991
PURL
http://purl.flvc.org/fcla/dt/14708
Subject Headings
Carcharhinus, Carcinogens, Golden hamster
Format
Document (PDF)
ORIENTATION OF BLACKTIP SHARKS (CARCHARHINUS LIMBATUS) TO UNDERWATER SOUND
Title
ORIENTATION OF BLACKTIP SHARKS (CARCHARHINUS LIMBATUS) TO UNDERWATER SOUND.
Creator
Sullivan, Caroline, Kajiura, Stephen, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
Abstract/Description
Sharks respond to low frequency pulsed sounds but are documented to lack the capacity to detect these sounds beyond the acoustic near field. The purpose of my study was to quantify the distance blacktip sharks (Carcharhinus limbatus) oriented to sound stimuli, and determine if responses occurred in the far field. Using an aerial drone and underwater speaker, C. limbatus were filmed responding to sound stimuli (100 – 200 Hz; 200 – 400 Hz; and 400 – 800 Hz). Upon detection, C. limbatus elicited...
Show moreSharks respond to low frequency pulsed sounds but are documented to lack the capacity to detect these sounds beyond the acoustic near field. The purpose of my study was to quantify the distance blacktip sharks (Carcharhinus limbatus) oriented to sound stimuli, and determine if responses occurred in the far field. Using an aerial drone and underwater speaker, C. limbatus were filmed responding to sound stimuli (100 – 200 Hz; 200 – 400 Hz; and 400 – 800 Hz). Upon detection, C. limbatus elicited a 20 – 160° turn from the speaker, and rapidly swam away. Sharks responded to all frequencies from at least 62 m, and 71.6% of all responses (n = 209) occurred in the far field. This indicates that blacktip sharks can detect and orient away from a sound stimulus at distances that extend beyond the acoustic near field, which suggests that they are not detecting sound using the inner ear otoconia.
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Date Issued
2022
PURL
http://purl.flvc.org/fau/fd/FA00014104
Subject Headings
Blacktip shark, Carcharhinus limbatus, Underwater sound
Format
Document (PDF)
MIGRATORY PATTERNS AND SEXUAL SEGREGATION IN THE BLACKTIP SHARK, CARCHARHINUS LIMBATUS, OFF THE UNITED STATES EAST COAST
Title
MIGRATORY PATTERNS AND SEXUAL SEGREGATION IN THE BLACKTIP SHARK, CARCHARHINUS LIMBATUS, OFF THE UNITED STATES EAST COAST.
Creator
Bowers, Mary Elizabeth, Kajiura, Stephen M., Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
Abstract/Description
Many marine species distributions have shifted poleward in response to global climate change. Many environmental characteristics will be affected by climate change including temperature and phytoplankton concentration; yet, photoperiod will remain the same. It is imperative to gather baseline distribution data on migratory species so that these shifts can be measured and mitigated. Sex-specific differences in reproductive strategies cause sexual segregation, sex-specific differences in...
Show moreMany marine species distributions have shifted poleward in response to global climate change. Many environmental characteristics will be affected by climate change including temperature and phytoplankton concentration; yet, photoperiod will remain the same. It is imperative to gather baseline distribution data on migratory species so that these shifts can be measured and mitigated. Sex-specific differences in reproductive strategies cause sexual segregation, sex-specific differences in spatial distribution. Female blacktip sharks exhibit a synchronous, biennial reproductive cycle in which one year of reproduction is followed by a resting year. Acoustic telemetry can be used in conjunction with collaborative networks to track migratory species over great distances. However, the irregular spacing of acoustic receivers often results in sporadic detection data, which can lead to skewed distribution information. This project developed and tested an analysis process to regularize sporadic acoustic detection data. Those regularized data were then applied to cluster analyses to determine the seasonal spatial distributions of blacktip sharks, Carcharhinus limbatus, off the United States East Coast and corresponding environmental correlates of latitudinal movement. Sexes of this population were investigated separately and in combination. Differences in distribution were evaluated between sexes, and within females, between reproductive states. These data showed that the U.S. East Coast blacktip shark population distributes from Palm Beach County, FL to Long Island, NY and exhibits sexual segregation, in which females display a more truncated migratory pattern than males.
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Date Issued
2023
PURL
http://purl.flvc.org/fau/fd/FA00014172
Subject Headings
Blacktip shark, Carcharhinus limbatus, Fishes--Migration
Format
Document (PDF)
THE BULL SHARK (CARCHARHINUS LEUCAS) AS A SENTINEL SPECIES FOR HARMFUL ALGAL BLOOM TOXINS IN THE INDIAN RIVER LAGOON, FLORIDA
Title
THE BULL SHARK (CARCHARHINUS LEUCAS) AS A SENTINEL SPECIES FOR HARMFUL ALGAL BLOOM TOXINS IN THE INDIAN RIVER LAGOON, FLORIDA.
Creator
Edwards, Michelle L., Ajemian, Matt, Florida Atlantic University, Department of Marine Science and Oceanography, Charles E. Schmidt College of Science
Abstract/Description
This study explored spatiotemporal patterns in movement, diet, and baseline phycotoxin concentrations in immature bull sharks (Carcharhinus leucas) of the Indian River Lagoon (IRL), an estuary of national significance that has been considerably impacted by multiple toxic harmful algal blooms (HABs). Long-term spatial use of the system was assessed for 29 acoustically tagged sharks over a 4 year period (2017–2020). Tissue samples for diet and toxin analysis were collected from a separate...
Show moreThis study explored spatiotemporal patterns in movement, diet, and baseline phycotoxin concentrations in immature bull sharks (Carcharhinus leucas) of the Indian River Lagoon (IRL), an estuary of national significance that has been considerably impacted by multiple toxic harmful algal blooms (HABs). Long-term spatial use of the system was assessed for 29 acoustically tagged sharks over a 4 year period (2017–2020). Tissue samples for diet and toxin analysis were collected from a separate cohort of 50 individuals between 2018 and 2020. UPLC-MS/MS was used to screen tissues for 14 algal toxins. Young bull sharks were found to be mainly piscivorous and displayed high residency to the IRL as well as to specific regions of the IRL, with small activity spaces. Multiple phycotoxins were detected in screened tissues, indicating that young bull sharks in the IRL may be compromised by trophic transfer of HABs while they reside in this important nursery.
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Date Issued
2021
PURL
http://purl.flvc.org/fau/fd/FA00013807
Subject Headings
Harmful Algal Bloom, Indian River (Fla. : Lagoon), Bull shark, Carcharhinus leucas, Sentinel Species
Format
Document (PDF)