Contributions of the measurement of TSH, T4 and thyroglobulin, of 99m Tc scintigraphy and of cervical ultrasonography to the early diagnosis of congenital hypothyroidism

Over 10 years, extending from 1978, 200,000 newborns of the Champagne-Ardennes Region have been tested within the screening program for congenital hypothyroidism. Congenital hypothyroidism was diagnosed in 96 infants (28 boys, 68 girls): 73 thyroid dysgenesis (50 ectopic glands and 23 undetectable thyroid tissue) and 23 thyroid dyshormonogenesis (14 permanent and 9 transient defects). Our local frequency was 1/2,600, significantly higher than the French and European frequencies. There was a marked shortening of the age at diagnosis during the 10 year period (mean age: 45 days between 1978 and 1980, 18 days in 1987). The TSH measurement was found to be the most sensitive tool for the diagnosis. Scintigraphy and more recently ultrasonography were performed in order to characterize the anatomical variety. For the last year, the following protocol was used: high frequency ultrasonography at first, then 123I or 99 m Tc scintigraphy (using parallel colimator and digital acquisition) depending on whether the thyroid gland was seen on ultrasound or not. Treatment of thyroid dyshormonogenesis was withdrawn after 5 years for reassessment.     

Corpus callosotomy for control of intractable epilepsy in children

Cerebral commissurotomy has often been reported to control seizures in patients suffering from intractable epilepsy. However, in adults, division of the corpus callosum alone has been shown to be equally effective while considerably reducing the surgical morbidity. The present study of nine epileptic callosotomized patients suggests that callosal section can also be performed successfully and safely in children. Neurologic and concomitant psychological improvements are described.     

Brief observations concerning the visual pigments of some selected fishes from Lake Heney, Quebec, a relict of glacial Lake Gatineau

The visual pigments and liver vitamins A of several races of Osmerus eperlanus mordax (rainbow smelt). Coregonus artedii (cisco), Myoxocephalus quadricornis thompsonii (deepwater sculpin). Cottus ricei (spoonhead sculpin) and Salrelinus namaycush (lake charr) have been examined. With the exception of Salvelinus and certain specimens of Osmerus, all were taken from Lake Heney. originally part of glacial Lake Gatineau at the time of the Champlain Sea episode, a marine inundation of the St Lawrence Lowlands that occurred some 9,000–12,000 yr ago. Osmerus has a rhodopsin with λ_max at 512 nm and a porphyropsin at 541 nm, the latter practically absent in the sympatric dwarf (including young-of-the-year) and giant races of Lake Heney. Coregonus has a rhodopsin with λ_max at 510–511 nm, perhaps with a trace of porphyropsin : Salvelinus has a rhodopsin and porphyropsin in variable amounts with respective maxima at 511 and 540 ± 2 nm. Of the two cottids. Cottus has a rhodopsin with λ_max at 503 nm but Myoxocephalus is unusual in having a mixture of two rhodopsins with maxima separated by only 7 nm. located at 508 and 515 nm respectively. All species have the precursor of porphyropsin. 3-dehydroretinol. in their livers in proportions ranging from 17 to 50 per cent of the total liver retinols. These findings are related to observations on kindred species in other habitats or other regions, and the visual pigments of the two cottids are discussed in relation to the recent evolution of these fish.     

Measurement of endometrial thickness with transvaginal ultrasonography: is it reproducible?

To assess the intraobserver and interobserver variability of transvaginal ultrasonographic measurement of endometrial thickness, two investigators (M.V., M.-F. D.) independently evaluated two successive measurements in 55 patients with a 5.0 MHz transvaginal transducer. Each observer was blinded to his or her own and to the other's results. Measurements were taken at the maximal thickness in the longitudinal uterine axis. The intraclass coefficients evaluating the agreement between two measures of a same observer were 94% and 97%; the coefficient was 94% between the two investigators. Intraobserver kappa values (agreement on endometrium < or = 5 mm and > 5 mm) were 0.70 and 0.81, respectively; the interobserver kappa value was 0.74. Transvaginal sonographic measurement of endometrial thickness has excellent intraobserver and good interobserver agreement. However, in clinical practice, an endometrial thickness measuring +/- 1 mm of a cut-off value should be interpreted with caution, especially when this may modify the clinical management.     

Use of bacteriophage-resistant mutants to study Actinomyces viscosus cell surface receptors

Spontaneously occurring bacteriophage-resistant mutants of Actinomyces viscosus were isolated. The mutants exhibited altered coaggregation patterns with streptococci. From analysis of the data, it appears that a cell surface structure on A. viscosus may function both as a phage receptor and as a binding site for co-aggregation with certain oral streptococci. These mutants will be valuable in the study of surface structures that mediate one type of the cell-to-cell interactions that occur between these two important groups of oral bacteria.     

Drug-induced long QT syndrome: hERG K+ channel block and disruption of protein trafficking by fluoxetine and norfluoxetine

BACKGROUND AND PURPOSE: Fluoxetine (Prozac) is a widely prescribed drug in adults and children, and it has an active metabolite, norfluoxetine, with a prolonged elimination time. Although uncommon, Prozac causes QT interval prolongation and arrhythmias; a patient who took an overdose of Prozac exhibited a prolonged QT interval (QTc 625 msec). We looked for possible mechanisms underlying this clinical finding by analysing the effects of fluoxetine and norfluoxetine on ion channels in vitro. EXPERIMENTAL APPROACH: We studied the effects of fluoxetine and norfluoxetine on the electrophysiology and cellular trafficking of hERG K+ and SCN5A Na+ channels heterologously expressed in HEK293 cells. KEY RESULTS: Voltage clamp analyses employing square pulse or ventricular action potential waveform protocols showed that fluoxetine and norfluoxetine caused direct, concentration-dependent, block of hERG current (IhERG). Biochemical studies showed that both compounds also caused concentration-dependent reductions in the trafficking of hERG channel protein into the cell surface membrane. Fluoxetine had no effect on SCN5A channel or HEK293 cell endogenous current. Mutations in the hERG channel drug binding domain reduced fluoxetine block of IhERG but did not alter fluoxetine's effect on hERG channel protein trafficking. CONCLUSIONS AND IMPLICATIONS: Our findings show that both fluoxetine and norfluoxetine at similar concentrations selectively reduce IhERG by two mechanisms, (1) direct channel block, and (2) indirectly by disrupting channel protein trafficking. These two effects are not mediated by a single drug binding site. Our findings add complexity to understanding the mechanisms that cause drug-induced long QT syndrome.     

A more diversified diet among Mexican men may also be more atherogenic

The objective of this study was to assess the nutritional quality of Mexican men's diet and its relation to socio-economic status (SES) and BMI. A random sample of 325 Mexican men, aged 35-65 y and stratified by SES and urban or rural residence, took part in the study. Two nonconsecutive 24-h dietary recalls were conducted in person. Dietary diversity was based on the consumption of 24 food groups. The micronutrient adequacy score that was used as a cut off was 75% of the U.S. RDA (Institute of Medicine) for 13 vitamins and minerals. A prevention score assessed subjects' adherence to 8 WHO dietary recommendations for the prevention of chronic diseases. Dietary diversity and micronutrient adequacy increased with SES status of urban subjects; these indices were also significantly higher among urban poor than among rural poor. In contrast, the prevention score tended to be higher among the poorer urban and rural respondents. Dietary diversity was significantly higher but the preventive score was significantly lower in obese subjects than in normal BMI subjects. There was a positive correlation between diet diversity and micronutrient adequacy (r = 0.34, P < 0.01), whereas dietary diversity and the prevention score were inversely correlated (r = -0.21, P < 0.01). The inverse association of dietary diversity and the prevention score was stronger in rural than in urban subjects. Dietary diversity was positively and significantly correlated with fruit and vegetable intake (r = 0.295, P < 0.001). It was, however, also positively correlated with the percent of energy from total and saturated fat, and cholesterol intake. Therefore, in some settings, higher food diversity may not predict a healthier diet from the standpoint of the prevention of chronic diseases.     

Malignant lymphomas (primary and secondary) of the thyroid. Description of 9 case reports and review of the literature

Malignant lymphomas of the thyroid are rare and represent approximately 0.3 to 8.9% of thyroid malignant neoplasms. We report 9 new cases; their clinical and histopathological features are discussed and compared with those of previously published series. Malignant lymphomas of the thyroid raise a number of issues: primary or secondary origin, histological typing (50% of cases are high grade lymphomas), differential diagnosis with either Hashimoto's chronic thyroiditis (often associated with thyroid lymphomas) or genuine anaplastic carcinoma of the thyroid. Routine histological study can be complemented by immunohistochemistry.     

Sudden loading perturbation to determine the reflex response of different back muscles: a reliability study

In this study we estimate the reliability of reflex response variables to identify the main sources of variability and to estimate appropriate measurement strategies to obtain more reliable measures. Back muscle surface electromyography (EMG) was recorded in healthy males during anteriorly-directed sudden loading perturbations applied to the trunk. Measures of EMG reflex latency and amplitude were obtained. The generalizability theory was used as a framework to estimate the magnitude of the different variance components and the reliability of the measures corresponding to various simulations of different measurement strategies. Reliability of the different variables was poor to moderate (intraclass correlation coefficient range 0-0.62). Averaging scores across homologous muscles and several trials were strategies to achieve more acceptable reliability. The reflex response of back muscles is inherently variable, and a large measurement effort is necessary to obtain reliable and, consequently, valid and responsive estimations of this neuromuscular function.