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Biomedical subjects

C A Anderson

Publications and source records attributed to C A Anderson.

At least 73 records · Page 4Linked to original sources
PubMed1990

External genitalia of the rat: normal development and the histogenesis of 5 alpha-reductase inhibitor-induced abnormalities.

The normal histogenesis of the rat genital tubercle and the effect of exposure in utero to the 5 alpha-reductase inhibitor finasteride (L-652,931; MK-0906; Proscar) on that process were studied. In normal males and females, the genital tubercle was first seen on Day 14.25 of gestation. It contained a urethral plate which extended from the cloaca (and after Day 15.25, from the urogenital sinus) to the tip of the tubercle. On Day 18.25 the glans lamellae, which would separate the glans penis or the clitoris from the prepuce, began to develop in both sexes. Also on Day 18.25 a dense, midline plate of mesenchymal cells was first evident between the urogenital sinus and the rectum in normal males. This plate acted as a wedge, first increasing the separation between the rectum and the urogenital sinus, and subsequently separating the urethral plate from the surface epithelium in the genital tubercle. As a result, by Day 21.25 the urethra in males followed an "S"-shaped course, extending from the pelvis through the center of the glans penis to an orifice near the tip of the genital tubercle. In females, in which a mesenchymal plate did not develop, the urethral orifice remained at the base of the tubercle, and the clitoris contained the remnants of the urethral plate, extending as an open groove from the urethral orifice to the tip of the tubercle. Finasteride did not affect development of the genital tubercle in females. However, in males exposed to finasteride in utero, there was variable failure of the mesenchymal wedge to develop. As a result, the urethral plate remained in contact with the surface epithelium and eventually opened to form a groove on the ventral surface of the glans penis (hypospadias). Also, the persistence of the urethral plate along the ventral midline in finasteride-treated male fetuses and its subsequent opening as a groove interfered with development of the glans lamellae, causing displacement of the frenulum distally on the glans penis and the development of a cleft in the prepuce.

Androstenes↗
PubMed1990

Army trauma research: tapping the potential.

Trauma management is the primary mission of military surgeons. Since the Vietnam War, however, military surgeons have relinquished leadership in clinical trauma care to the civilian sector, particularly to urban university surgeons. In this paper we explore whether the Army's contribution to trauma research has also diminished. Using standard bibliometric analysis of publication counts, we have shown that few recent publications related to trauma have originated from U.S. Army Medical Centers, compared with adjacent civilian universities. In 1988, 16 papers originating from the eight Army Medical Centers had key words related to trauma. In contrast, eight universities adjacent to the Army's medical centers published 139 articles on trauma. Problems including lack of clinical exposure to trauma patients, lack of funding, and inadequate emphasis on staff research training have contributed to this decline. We review these factors and describe solutions that could reverse this trend.

Humans↗
PubMed1989

Protective effect of a synthetic peptide comprising the complete preS2 region of the hepatitis B virus surface protein.

A peptide was synthesized containing the entire 55 amino acid residue sequence of the hepatitis B virus (HBV) surface antigen preS2 region (ad subtype). The unconjugated peptide was inoculated into four chimpanzees. Following multiple injections, all of the animals developed specific antipeptide antibodies that reacted with intact surface antigen particles bearing the preS2 moiety. All four peptide-inoculated animals were found to be protected from infection after intravenous challenge with live HBV of either the ad or ay subtypes.

Animals↗
PubMed1989

Temperature and aggression: ubiquitous effects of heat on occurrence of human violence.

Outlines 5 models of the temperature-aggression hypothesis: negative affect escape, simple negative affect, excitation transfer/misattribution, cognitive neoassociation, and physiological-thermoregulatory. Reviews relevant studies. Aggression measures include violent crime, spouse abuse, horn-honking, and delivery of electric shock. Analysis levels include geographic regional, seasonal, monthly, and daily variations in aggression, and concomitant temperature-aggression effects in field and laboratory settings. Field studies clearly show that heat increases aggression. Laboratory studies show inconsistencies, possibly because of several artifacts. Specific models have not been adequately tested, but the excitation transfer/misattribution and cognitive neoassociation approaches appear most promising, whereas the negative affect escape appears the least viable. Suggestions for future work are made.

Aggression↗
PubMed1987

Temperature and aggression: effects on quarterly, yearly, and city rates of violent and nonviolent crime.

The hypothesized relation between uncomfortably hot temperatures and aggressive behavior was examined in two studies of violent and nonviolent crime. Data on rates of murder, rape, assault, robbery, burglary, larceny-theft, and motor vehicle theft were gathered from archival sources. The first three crimes listed are violent; the latter four are less violent (labeled nonviolent). On the basis of previous research and theory (Anderson & Anderson, 1984), it was predicted that violent crimes would be more prevalent in the hotter quarters of the year and in hotter years. Furthermore, it was predicted that this temperature-crime relation would be stronger for violent than for nonviolent crime. Study 1 confirmed both predictions. Also, differences among cities in violent crime were predicted to be related to the hotness of cities; this effect was expected to be stronger for violent than for nonviolent crimes. Study 2 confirmed both predictions, even when effects of a variety of social, demographic, and economic variables were statistically removed. Theoretical and practical implications are discussed.

Aggression↗
PubMed1987

Neurovirulence of the UC-2 and UC-8 strains of bluetongue virus serotype 11 in newborn mice.

In vivo and in vitro experiments were done to investigate whether the difference in neurovirulence between the two strains of bluetongue virus 11, UC-2 and UC-8, is based on a different capability to gain access to the brain from the subcutaneous inoculation site or on a different tropism for neural cells. In newborn Balb/c mice subcutaneous inoculation of UC-8 at doses between 10(-0.2) plaque forming units (PFU) and 10(4.8) PFU caused a severe necrotizing encephalitis whereas UC-2 at doses of up to 10(4.4) PFU did not affect newborn Balb/c mice. However, intracranial inoculation of 10(2.4) PFU of either virus strain produced severe necrotizing encephalitis. In vitro both virus strains infected dissociated brain cell cultures similarly. Double labelling immunofluorescent staining with markers specific for neural cells did not reveal differences in the target cells for the two viruses. The difference in neurovirulence between UC-2 and UC-8, therefore, appears to be determined by the ability of UC-8 to infect the brain from a subcutaneous inoculation site.

Animals↗
PubMed1987

Border disease. Virus-induced decrease in thyroid hormone levels with associated hypomyelination.

Border disease (BD) was induced in lambs by inoculation of their dams at 50 days gestation with Border disease virus (BDV) isolate #31. At birth, the clinically affected lambs had diffuse spinal cord hypomyelination, confirmed by immunocytochemical staining for myelin-associated glycoprotein and myelin basic protein. In the BD lambs, large numbers of thyroid follicular epithelial cells and scattered pituitary cells contained BDV antigen by immunofluorescence staining. Double labeling techniques demonstrated the BDV-infected pituitary cells to contain growth hormone, adrenocorticotrophic hormone, prolactin, or luteinizing hormone. Cells containing thyroid stimulating hormone were rare and were not positive for BDV antigen. Infection of the pituitaries and thyroid glands caused no detectable morphologic changes as compared to controls. The BD lambs had statistically significantly (p less than 0.05) lower mean serum concentrations of thyroxine and L-3,3',5-triiodothyronine as compared to age-matched uninfected controls. Similar significant differences in the mean plasma levels of growth hormone and thyroid stimulating hormone were not found. In addition, the BD lambs had a statistically significant (p less than 0.05) lower mean activity of the myelin-associated, thyroid hormone dependent enzyme, 2',3'-cyclic nucleotide-3'-phosphodiesterase in spinal cord tissue. Although not conclusive, these results indicate that the hypomyelination in BD may be due to depressed levels of circulating thyroid gland hormones secondary to a noninflammatory and noncytolytic infection of the thyroid gland by BDV. This is one of the first reports indicating that a virus-induced hormonal alteration may cause a congenital lesion in animals.

Animals↗
PubMed1987

Experimentally induced ovine border disease: extensive hypomyelination with minimal viral antigen in neonatal spinal cord.

Border disease (BD) was experimentally induced in 9 lambs by inoculation of their dams with the BD-31 strain of border disease virus (BDV) at 50 days of gestation. These ewes developed serum-neutralizing antibody titers to BDV. The diagnosis of BD in their lambs was confirmed by hairy birthcoats, intrauterine growth retardation, tremors, and hypomyelination. Three clinically healthy age-matched control lambs, whose dams had been given an inoculum containing only BDV-free cell culture supernatant, were studied in parallel. There were significant differences in birth weights and in the lengths of the right tibiae and radii between the affected and the control lambs. There was a gradient in severity of clinical neurologic signs among the affected lambs, which directly correlated with the severity of hypomyelination in their spinal cords. However, the difference in severity of the neurologic deficits did not correlate with differences either in the precolostral serum-neutralizing antibody titers to BDV in these lambs or in the number of BDV antigen-containing cells in their spinal cords. Only approximately 0.01% to 0.3% of spinal cord cells, both in gray matter and white matter, were BDV antigen positive in the affected lambs. These results indicate that extensive infection of CNS cells with their subsequent destruction or functional alteration may not be a critical part of the pathogenesis of the hypomyelination in BD.

Animals↗
PubMed1987

Enzyme-linked immunosorbent assay for the detection of antibodies to bovine virus diarrhea virus in sera from border disease virus-infected sheep.

An enzyme-linked immunosorbent assay (ELISA) was established for the rapid detection of specific antibodies against the causative agent of border disease in ovine sera. Polyethylene-glycol concentrated, equilibrium density gradient purified bovine virus diarrhea virus was used as test antigen. The optimal amount of antigen was 0.5 microgram/well, and the optimal concentration of conjugate was at 1/4,000 dilution. A total of 20 ovine serum samples, which had been collected from animals with or without border disease, were compared by ELISA and serum neutralization test for the detection of border disease-specific antibodies. ELISA was shown to be equally specific but less time-consuming and easier to perform than serum neutralization test. A positive correlation (r = 0.60) between the two tests was found.

Animals↗
PubMed1987

Tropism of border disease virus for oligodendrocytes in ovine fetal brain cell cultures.

Primary dissociated ovine brain cell cultures prepared from 50- or 140-day-old fetuses were inoculated with border disease virus (BDV). The cells present in the cultures were identified, using immunofluorescence procedures and sera against various CNS cell-specific markers. These markers were glial fibrillary acidic protein, myelin basic protein, myelin-associated glycoprotein, neuron-specific enolase, neurofilament protein, and fibronectin. Double-labeling immunofluorescence techniques for visualization of BDV antigen and of the CNS cell markers were used to evaluate the pattern of individual cell susceptibility 48 hours after infection. In cultures from fetuses of both ages, about half of the infected cells were glial fibrillary acidic protein-positive astrocytes. Scattered myelin-associated glycoprotein-positive oligodendrocytes were positive for BDV antigen, but only in the infected cultures from the older fetuses. Fibronectin-positive cells were not infected with BDV. In infected and noninfected cultures, cells positive for neuron-specific enolase, myelin basic protein, or neurofilament protein were not seen. Therefore, the remaining infected cells in all the cultures were not identified by the cell-specific markers used. Results of these in vitro experiments indicate that BDV does not selectively infect oligodendrocytes, and that such a selective pattern of infection may not be the basis for the in vivo congenital hypomyelination in sheep with border disease.

Animals↗
PubMed1986

Detection of cumulative trauma disorders of upper extremities in the workplace.

Surveillance for musculoskeletal disorders of the upper extremity in industry is in its infancy. Research efforts to elucidate the causal factors of these disorders often rely on either the analysis of existing medical records, worker compensation records (passive surveillance), or the surveying of workers with questionnaire and physical examination (active surveillance). The use of either type of data for routine surveillance presents several difficulties illustrated with the results presented in this paper. The analysis of existing records is generally less costly but the reliability of the data is difficult to assess. Standardized questionnaire and physical examinations can be as sensitive as the use of unusually thorough existing occupational medical records; however, it is unclear whether the additional cost of an active surveillance system will deter the routine use of such systems.

Arm↗
PubMed1986

Surveillance of mice for antibodies to murine cytomegalovirus.

The sera of 256 mice from nine commercial sources were screened for antibodies to murine cytomegalovirus (MCMV) because a surveillance of this virus has not been reported in the literature for over a decade. Although no evidence of antibodies to MCMV were detected by complement fixation or nuclear anticomplement immunofluorescence, 54.7% of these sera did have antibodies that were detected by enzyme-linked immunosorbent assay. These data emphasize the need for proper containment of laboratory mice to prevent the potential outbreak of acute MCMV infection. Including MCMV antibody surveillance by enzyme-linked immunosorbent assay in routine health monitoring of mice and imparting these findings in an analysis of the role of MCMV on interpretation of experimental results is advised.

Animals↗
PubMed1985

Ocular infection with herpes simplex virus (HSV-1) in vitamin A-deficient and control rats.

An experimental model was developed for studying ocular infections with herpes simplex virus (HSV) type 1 in vitamin A-deficient (-A) and pair-fed control (+A) rats. The severity and course of the disease was evaluated by clinical examination, slit lamp biomicroscopy and histopathologic observations. Experimental animals were in good health and were infected in the early stages of vitamin deficiency (either prior to or at the beginning of the weight plateau). In all trials the onset of herpetic keratitis was more rapid and the clinical disease more severe in -A rats compared to +A controls. Mean slit lamp scores (which assessed the severity of the corneal disease) increased from 3 to 10 d after infection and were higher (P less than 0.002) in -A rats at all time points and doses of virus tested. The inflammatory response in the cornea and uveal tract of -A rats was significantly higher than that of +A animals. Since ocular HSV disease is a common cause of blindness, the availability of a rat model should be valuable in studies of the role of nutritional factors in host susceptibility and response to viral challenge. Mild vitamin A deficiency increased the severity of experimental corneal HSV infections and resulted in a high incidence of epithelial ulceration and necrosis.

Animals↗
PubMed1984

Ambient temperature and violent crime: tests of the linear and curvilinear hypotheses.

Laboratory research on the effects of temperature has led theorists to propose a curvilinear model relating negative affect and aggression. Two alternative explanations of these lab findings are proposed--one artifactual, one based on attributions for arousal. Both alternatives predict a linear relationship between temperature and aggression in real-world settings, whereas the negative affect curvilinear model predicts a specific curvilinear effect. Two studies are reported that investigated the relationship between temperature and violent crime. Both studies yielded significant linear relationships and failed to demonstrate the specified curvilinear relationship. Also, both studies yielded significant day-of-the-week effects. Implications of these findings for the study of aggression are discussed.

Aggression↗
PubMed1984

Competition.

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Costs and Cost Analysis↗