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A Childress

Publications and source records attributed to A Childress.

5 recordsLinked to original sources

Intranuclear coccidiosis in tortoises: nine cases.

Chelonian intranuclear coccidiosis has been reported once, in two radiated tortoises (Geochelone radiata), and is apparently rare. We describe intranuclear coccidiosis diagnosed histologically in two radiated tortoises, three Travancore tortoises (Indotestudo forstenii), two leopard tortoises (Geochelone pardalis), one bowsprit tortoise (Chersina angulata), and one impressed tortoise (Manouria impressa). Infection was systemic and involved alimentary, urogenital, respiratory, lymphoid, endocrine, and integumentary systems. Trophozoites, meronts, merozoites, macrogametocytes, microgametocytes, and nonsporulated oocysts were seen histologically or by electron microscopy. Intracytoplasmic and extracellular stages of parasite development also were identified histologically. Sequencing of a coccidial 18S rRNA consensus polymerase chain reaction (PCR) product revealed a novel sequence that provided phylogenetic information and may be useful for further diagnostic test design. Intranuclear coccidiosis was associated with variable degrees of inflammation in all cases, was considered the cause of death in six tortoises, and was a substantial contributing factor to the cause of death in two tortoises.

Animals↗

Conditioned craving and arousal in cocaine addiction: a preliminary report.

Though data collection is still in progress, several significant findings are already apparent from our study of cocaine 'reminders': 1) In the laboratory, detoxified cocaine abusers show a differential responsivity to drug-related cocaine 'reminders', responding with strong signs of physiological arousal (peripheral skin temperature reductions and decreases in skin resistance) and subjective cocaine craving. 2) In extinction sessions, repeated, non-reinforced exposure to cocaine 'reminders' led to a complete reduction in craving to these stimuli by the fifteenth hour-long session. High and 'crash' responses were virtually eliminated by the sixth hour of extinction. 3) Physiological arousal to cocaine 'reminders' was often still in evidence even after fifteen hours of extinction. 4) Even after completing the current extinction protocol cocaine abusers may crave--and use--cocaine when experiencing drug 'reminders' in the natural environment. Clearly, detoxified cocaine abusers can experience conditioned craving and arousal to cocaine 'reminder' stimuli. These responses can be both intense and persistent, meaning that the abstinent cocaine abuser may be vulnerable long after detoxification is complete. Though the program of extinction described here is effective in reducing craving to cocaine-related stimuli presented in the context of the laboratory or clinic, this effect may not generalize well to the natural environment. We are currently considering two approaches to this problem: 1) One approach would attempt to increase the generalization of extinction by the use of even more realistic stimuli (e.g., the sight of real cocaine) and stimulus contexts (e.g., in vivo repeated exposures).(ABSTRACT TRUNCATED AT 250 WORDS)

Cocaine↗

Update on behavioral treatments for substance abuse.

In the past five years there has been an encouraging increase in the amount and quality of research on behavioral treatments for substance abuse. Some of the most promising approaches combine behavioral treatments with each other (e.g., relapse prevention and cue exposure) or with other forms of treatment (e.g., psychotherapy), attempting to maximize impact on the multiple determinants of drug use. We are fast approaching the time when a patient may be systematically evaluated to develop a profile of vulnerabilities (cue responsivity, psychiatric symptoms, etc.) to rationally determine the treatment or combination of treatments of greatest potential benefit.

Behavior Therapy↗