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Biomedical subjects

A W Smith

Publications and source records attributed to A W Smith.

At least 127 records · Page 7Linked to original sources
PubMed1985

Alterations in head dynamics with the addition of a hockey helmet and face shield under inertial loading.

The effect of a hockey helmet and face shield on the head and neck during inertial loading was studied. A Hybrid III Anthropometric Test Dummy (ATD) was struck from both the front and rear by a spring-loaded, instrumented striker moving at 2.9 ms-1. Data were collected from a triaxial force transducer mounted at the atlanto-occipital (a-o) junction of the ATD, a load cell in the striker, and by cinematography (250 fps). Angular kinematics of the head and moments of force about the a-o junction were determined along with impact force levels. When compared to a bare-head condition, the addition of a helmet and face shield caused an increase in head angular displacement (20-40%) but did not affect head angular acceleration. Axial and shear forces at the a-o junction did not change appreciably with the addition of a helmet and face shield. A triphasic pattern was evident for the neck moments including a small phase which represented a seating of the headform on the nodding blocks of the uppermost ATD neck segment, and two larger phases of opposite polarity which represented the motion of the head relative to the trunk during the first 350 ms after impact. No substantial differences were apparent between the helmeted and non-helmeted trials. The magnitudes of forces and moments found in the present study were well within tolerance levels reported by others (Melvin, 1979; Cheng et al., 1982). It was concluded that the increase in angular displacement of the head, with the addition of a helmet and face shield, does not place the wearer in a position of increased risk of cervical spine trauma.

Athletic Injuries↗
PubMed1983

Regression of cetacean tattoo lesions concurrent with conversion of precipitin antibody against a poxvirus.

Tattoo lesions linked to the cetacean poxvirus of bottlenose dolphins regressed without treatment. Two types of regression were observed: (1) The tattoo lesions became raised and blanched, then disappeared along with sloughing skin. (2) When an incision was made through a tattoo lesion, the tattoo disappeared in a zone around the incision. Poxviruses removed from the raised, blanched skin lesions and from typical tattoo lesions were reacted with dolphin serums and examined by immunoelectron microscopy. Antibody was not detected against either of these poxvirus preparations when the dolphins had only typical tattoo lesions. However, after the raised, blanched lesions appeared, serums obtained during the acute or convalescent stages were positive for the poxvirus separated from the lesions. Regression of the typical tattoo lesions was concurrent with antibody conversion.

Animals↗
PubMed1983

Calicivirus-induced vesicular disease in cetaceans and probable interspecies transmission.

A calicivirus isolated from cetaceans is a new serotype designated cetacean calicivirus Tursiops-1 (CCV-Tur-1). It appears to have spread from an initially infected Atlantic bottlenose dolphin to a California sea lion, and was then carried by the sea lion to a second facility several miles away, where a second dolphin became infected and developed vesicular skin lesions that eroded, leaving shallow ulcers. Cetaceans and pinnipeds belong to separate orders, so this finding of interspecies transmission demonstrates the potentially broad host spectrum for yet another calicivirus.

Animals↗
PubMed1983

Calicivirus isolation and persistence in a pygmy chimpanzee (Pan paniscus).

What may be the first calicivirus isolate from any primate species, including man, was recovered from a herpesvirus-like lip lesion on a pygmy chimpanzee and then, 6 months later, from the throat of the same animal. The infected individual and its cage mates had circulating antibodies that were type-specific for this calicivirus. The agent was antigenically different from 30 other calicivirus serotypes and is tentatively designated primate calicivirus Pan paniscus type 1 (PCV-Pan 1).

Animals↗
PubMed1983

Ultrastructure of newly recognized caliciviruses of the dog and mink.

Two recently recognized viruses obtained from a dog with glossitis and from mink with hemorrhagic pneumonia were characterized by electron microscopy. The results of the negative-stained preparations indicated that the viruses were structurally compatible with the calicivirus group.

Animals↗
PubMed1983

Isolation and partial characterization of a calicivirus from calves.

A calicivirus was isolated from 3 dairy calves in a herd with persistent calf respiratory tract problems. This virus, named Tillamook calicivirus, was not neutralized by 18 different calicivirus-typing serums available. The agent caused only minimal lesions in 2 experimentally exposed calves, but did establish a persistent infection with virus shedding for 45 days, after which time the experiment was terminated. Experimentally exposed swine developed clinical vesicular lesions. The possible origins, disease potential, and relationships to the exotic animal disease agent, vesicular exanthema of swine are discussed for this first calicivirus isolate of bovine origin.

Animals↗
PubMed1981

Isolation and identification of five new serotypes of calicivirus from marine mammals.

Five new serotypes of calicivirus have been isolated from marine mammals. San Miguel sea lion virus (SMSV)-8 and SMSV-10 were recovered from vesicular lesions on the flippers of northern fur seals in the Pribilof Islands of Alaska. Serotype SMSV-9 was isolated from a sea lion in southern California, and SMSV-11 was isolated from 2 northern fur seal pups in southern California. Serotype SMSV-12 was also isolated in southern California from sea lion and fur seal pups.

Animals↗
PubMed1980

Caliciviridae.

The caliciviruses, as a proposed family Caliciviridae, have a distinct virion morphology with cup-shaped depressions on a spherical capsid surface. The viruses have single-stranded RNA, which has a molecular weight about 2.6 x 10(6) and is infectious. The RNA is covalently linked to a small protein. A single major polypeptide is found in the capsid. A subgenomic RNA, molecular weight about 1 x 10(6), coding for the capsid polypeptide is found in infected cells. Caliciviruses infecting swine, pinnipeds and cats have been characterized. Viruses which are morphologically identical to the known caliciviruses have been identified in human feces; these viruses have been shown to be associated with gastroenteritis, but they have not yet been propagated in the laboratory.

Animals↗
PubMed1980

Preliminary investigation of a possible lung worm (Parafilaroides decorus), fish (Girella nigricans), and marine mammal (Callorhinus ursinus) cycle for San Miguel sea lion virus type 5.

Colostrum-deprived neonatal Northern fur seal pups (Callorhinus ursinus) were exposed to San Miguel sea lion virus type 5 (SMSV-5) by feeding them fish (Girella nigricans) infected with virus or fish infected with both the sea lion lung worm larvae (Parafilaroides decorus) and virus. Virus infection was demonstrated in 8 of 9 pups, and 1 of these developed a vesicular lesion on the flipper. In this sequence, P decorus larvae exposed to SMSV-5 were fed to G nigricans held at 15 C in a salt water aquarium; 32 days later, these fish were killed, then fed to the fur seal pups. The vesicle developed 22 days subsequent to this and SMSV-5 was reisolated from the lesion. The SMSV-5 was shown to persist for at least 23 days in infected neonatal fur seals. Attempts to establish P decorus infection in Northern fur seal pups were apparently unsuccessful.

Animals↗
PubMed1979

Viruses and virus diseases of marine mammals.

Poxvirus and several serotypes of calicivirus cause recognizable disease in marine mammals. Pox lesions in pinnipeds are raised and proliferative and are seen most frequently after confinement in captivity. In cetaceans, a poxvirus is associated with a much more benign and chronic lesion called a "tattoo." Numerous caliciviruses of differing antigenic types have been isolated from vesicular lesions and aborted fetuses of northern fur seals and California sea lions as well as from clinically normal and orphaned northern elephant seal pups. An adenovirus has been isolated from a sei whale and an enterovirus has been isolated from a gray whale.

Adenoviridae↗
PubMed1979

A new calicivirus isolated from a marine mammal.

A new serotype of calicivirus, designated as San Miguel sea lion virus type 6 (SMSV-6), was isolated from vesicular lesions on the flipper of a California sea lion pup. Serologic studies show that SMSV-6 neutralizing antibodies (SN) occur frequently among California sea lions and occasionally among northern fur seals. Feral swine, 1- to 6-week elephant seal pups and grey whales tested negative for SMSV-6 antibody.

Animals↗
PubMed1978

Hazards of disease transfer from marine mammals to land mammals: review and recent findings.

In a 5-year study (1972-1977) of microbial agents isolated from both clinically normal and diseased marine mammals, it was shown that certain disease agents are widespread in a diversity of ocean populations and that some are also transmissible to a number of terrestrial mammal species. Leptospira interrogans serovar pomona has been isolated repeatedly from 2 species of pinnipeds (Zalophus californianus califonianus and Callorhinus ursinus). Some of the more important bacterial pathogens for land mammals that were isolated from wild marine mammals are Pseudomonas mallei, Clostridium chauvoei, C novyi, Neisseria mucosa var heidelbergensis, Klebsiella pneumoniae, Salmonella spp, and Pasteurella multocida. Numerous serotypes of viruses classified as caliciviruses were isolated from a variety of marine mammals. Some of these are known to infect several land mammal species including swine horses, and primates. For this reason., precautions should be taken to ensure that disease agents shed by captive marine mammals are not transmitted to susceptible terrestrial mammals, including animal handlers and other human beings.

Animals↗