PITUITARY AND PERIPHERAL RESISTANCE TO THYROID HORMONE

A 32-year-old Caucasian male, clinically euthyroid, with paranoid schizophrenia and granulocytopenia, had elevated total and free serum T4 and T3; serum TSH was normal (2.7 +/- 0.7 micronU/ml). There was no goitre present, no evidence of Graves' disease, and no evidence of pituitary tumour. He had a normal response to methyl-TRH, with a TSH increment of 14.6 micronU/ml, T3 increment of 212 ng/dl, and T4 increment of 4.7 microgram/dl; baseline value and decreased the TSH increment in response to methyl-TRH. T3 therapy (100 microgram/day) decreased the thyroidal radioactive iodine uptake to less than half the baseline prolactin was normal with a normal response to methyl-TRH to 4.1 micronU/ml. Iodine therapy caused an increase in his baseline TSH with an increase in the TSH response to TSH. The metabolic clearance rates (MCR) and production rates (PR) of T3 and T4 were increased. Baseline serum levels of glycoprotein hormone alpha-subunit were normal and showed a slight increase in response to methyl-TRH, similar to normal subjects. This patient has evidence of partial pituitary and peripheral resistance to thyroid hormone; his only evidence for hyperthyroidism is the elevated MCR and PR of T3 and T4.     

The Kinetics of Skin Cancer: Progression of Actinic Keratosis to Squamous Cell Carcinoma

BACKGROUND: Actinic keratoses (AKs) are intraepidermal skin tumors that have the potential to progress to squamous cell carcinomas (SCCs). SCCs are the second most common cancer with more than 200,000 cases each year in America. Approximately 10% of AKs will progress to SCCs. This progression is thought to be due to chronic sun exposure, specifically ultraviolet B sunlight. OBJECTIVE: Understanding the kinetics of this developmental process can help physicians better evaluate and subsequently treat precancerous AKs. METHODS: To determine the time scale of AK progression, we conducted a retrospective electronic medical record study of all patients diagnosed histopathologically with an SCC between July 1, 2003, and June 30, 2005. RESULTS: Of a total patient population of 6,691, 91 had a histopathologically confirmed diagnosis of an AK at the same site as the subsequent SCC. The length of time for an AK to progress to an SCC was determined to be 24.6 months (95% confidence interval, 21.04-28.16 months). CONCLUSIONS: Although a more controlled in vivo study is indicated, these data provide a good estimate of the time course from an AK to an SCC. In summary, of the estimated 10% of AKs that will develop into an SCC, the progression will take approximately 2 years.     

Triphenyl Phosphite and Diisopropylphosphorofluoridate Produce Separate and Distinct Axonal Degeneration Patterns in the Central Nervous System of the Rat

This study compared the neurotoxic effects of triphenyl phosphite(TPP) in the rat with those seen after exposure to diisopropylphosphorofluoridate(DFP), a compound known to produce organophosphorus-induceddelayed neurotoxicity (OPIDN). Animals received either threesubcutaneous injections of TPP (1184 mg/kg body wt each dose)administered at 3-day intervals or a single subcutaneous injectionof DFP (4 mg/kg body wt). TPP-induced clinical signs were initiallyobserved 2 to 18 days after the last injection and includedataxia, flaccid paresis, stereotyped alternating side-to-sidemovements, and circling behavior. Axonal and terminal degenerationwere present in the cerebellum, vestibular nuclear complex,cochlear nuclei, and superior and inferior colliculi. The subthalamicnucleus, substantia nigra, septal region, hypothalamus, thalamus,hippocampus, and cerebral cortex also contained degeneratingaxons and terminals. Degeneration was particularly evident inthe sensorimotor cerebral cortex, mediodorsal, ventromedial,and medial geniculate thalamic nuclei and in the magnocellularpreoptic and medial mammillary nuclei of the hypothalamus. Verylight degeneration was present in the gracile fasciculus andnucleus. In contrast, rats injected with DFP showed moderatedegeneration in the gracile fasciculus and nucleus but did notdisplay degeneration in any other brain region. Injections ofDFP did not produce delayed onset clinical signs. The resultsindicate that in the rat, different central nervous system cellgroups are affected by these two organophosphorus compoundsand that TPP affects nuclei and tracts at all levels of theneuraxis, including those associated with higher-order processingand cognitive functions. In addition, the distinct degenerationpatterns produced by these two compounds support the view thatTPP-induced neurotoxicity should not be considered as a typeof OPIDN, but rather as a separate category of organophosphorus-inducedneurotoxicity.     

Threadworms and IgE in allergic asthma

A high incidence of infection with the threadworm Enterobius vermicularis has been demonstrated in a group of children with allergic asthma, but also in a non-allergic group. There was no evidence of infection with any other helminth parasites. Presence or absence of threadworm infection was not clearly correlated with differences in total serum IgE level in either allergic or non-allergic children although levels of this immunoglobulin were raised in the former group. Some of the allergic children gave positive skin reactions following intradermal injection of an antigen extracted from E. vermicularis. The suggestion is therefore put forward that hypersensitivity to E. vermicularis allergen absorbed from the bowel might contribute to the allergic symptoms. The results are also discussed in relation to recently discovered experimental evidence that helminth infection may non-specifically potentiate unrelated IgE antibody responses.     

Intensity of Jogging

The relationship between intensity of jogging and various menstrual/reproductive factors in women were investigated. Data were collected by questionnaire from 319 women who participated in a running event that included both a 6.2-mile (10 K) run and a 26.2-mile marathon in northeastern Ohio. Findings reaffirmed the notion that scant menstrual flow, skipped menses, and menstrual irregularity are significantly related to the intensity of jogging; age at menarche, infertility, and uterine prolapse were not. Thirty-two percent of the women felt that jogging decreased their menstrual discomfort, and 44% reported better jogging performance right after or between menstrual periods.     

Inconsistencies in lifetime cocaine and marijuana use reports: impact on prevalence and incidence

We evaluated inconsistencies in responses to questions about lifetime cocaine and marijuana use asked of nearly 10 000 respondents from the United States in the National Longitudinal Survey of Youth in 1984 and 1988. Our analyses showed that 14% of all responses on cocaine use and 17% of all responses on marijuana use were inconsistent in some way. The types of inconsistencies varied according to the substance; cocaine reports yielded more inconsistencies with regard to timing of first use, while for marijuana most of the inconsistencies were with respect to use disclosure. For both substances, lower level users were more likely to be inconsistent in their reports of drug use. Alternative methods for handling inconsistencies affected estimates of incidence and prevalence. Inconsistencies also varied according to respondent race/ethnicity. Implications of these findings for program evaluation are discussed.     

Comparison of the Effectiveness of Videotape versus Live Group Infant Care Classes

Postpartum women on a hospital maternity unit viewed a videotape on infant care or attended a group class on infant care. Content quiz scores for the two groups were not significantly different. Although the majority of both groups thought the live class was a better way to teach new mothers about infant care, no significant differences on measures of convenience, ease of understanding, level of interest, amount learned, and how relaxed the mother felt were identified.