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Biomedical subjects

M Katchen

Publications and source records attributed to M Katchen.

7 recordsLinked to original sources
PubMed1989

Evaluation of the sleepy crewmember: USAFSAM experience and a suggested clinical approach.

From 1958 to 1986, 27 crewmembers with suspected sleep disorders were referred to the USAF School of Aerospace Medicine. The presenting complaint in most cases was excessive daytime sleepiness (EDS). Prior to 1984, evaluations included neurologic and psychiatric testing, screening laboratory studies, and awake and asleep electroencephalography. Polysomnography and sleep latency studies were included after 1984. In the majority of cases, the etiology of the complaint could not be determined. The prevalence of EDS is estimated to be between 0.3% and 4.0% of the adult population. Major causes cited in the world literature include the sleep apnea syndromes, narcolepsy, parasomnias interrupting sleep, hypersomnia secondary to systemic or affective disorders, and essential hypersomnia. Current sleep lab techniques and human leukocyte antigen (HLA) typing are reported to make the diagnosis in up to 90% of sleep disorders. Evaluation of EDS should begin with a history emphasizing sleep habits, work schedules, daytime naps, and presence of vegetative signs. A sleep diary will allow a more accurate estimate of the quantity of nocturnal sleep. This diary may reveal poor sleep hygiene or insomnia. Polysomnography and/or multiple sleep latency determination can then be used to diagnose sleep apnea, parasomnias, and narcolepsy.

Adult↗
PubMed1988

Comparative dermal carcinogenesis of shale and petroleum-derived distillates.

Ten test materials derived from petroleum or hydrotreated shale oils were applied 3 times/week for up to 105 weeks to the shaved skin of 25 male and 25 female C3H/HeN mice per group. Mineral oil and benzo(a) pyrene (0.15%) were control materials. Clinical observations were recorded during the study. At death, histopathologic examination was conducted on skin, internal organs and any gross lesions. Exposures to some materials were ended midway in the study due to severe irritation. Chronic toxicity of all materials was limited to inflammatory and degenerative skin changes. Significant increases over control incidence of skin tumors (squamous cell carcinoma and fibrosarcoma) occurred with both petroleum and shale-derived naphtha (21%, 50%), Jet A (26%, 28%), JP-4 (26%, 50%), and crude oils (84%, 54%). Severely hydrotreated shale oil and petroleum and shale-derived diesel distillates were not considered tumorigenic. Results indicate that toxicity of comparable petroleum and shale-derived fractions was qualitatively similar and confirm earlier findings that hydrotreating reduces or eliminates carcinogenicity of raw shale oil.

Animals↗
PubMed1986

Parkinsonism following dystonia in three patients.

Three patients who presented initially with dystonia and subsequently developed typical idiopathic parkinsonism were evaluated. One patient presented with a writer's cramp, one with axial dystonia, and one with Meige syndrome. All three displayed amelioration of their dystonia with progression of their parkinsonism over a period of 2 to 15 years. Treatment with levodopa gave some relief of the parkinsonism symptoms in two patients but exacerbated or reactivated the dystonia. It is suggested that both the dystonia and the parkinsonism represent the changing clinical expression of the same disorder at different times in its evolution.

Adult↗