Value of Doppler ultrasound for the diagnosis of renal artery stenosis in children

To evaluate the reliability of Doppler ultrasonography (US) in identifying children with renal artery stenosis (RAS) among those with hypertension, we compared Doppler US results in 22 hypertensive children (mean age 8.9±4.3 years), with (13 cases) and without RAS at angiography, and in 33 normotensive children (mean age 8.8±4.7 years). We observed 2 false-negatives and 2 false-positives with Doppler US. Of the 2 false-negative diagnoses, 1 had RAS on an accessory renal artery located behind a normal upper polar artery and the other was observed in a patient with bilateral multiple stenosis of the very distal segments of renal arteries. The 2 false-positive diagnoses were due to sinuous left renal artery and to technical reasons, respectively. In another patient, Doppler US showed a tight RAS, while arteriography was normal. RAS was subsequently confirmed by a second arteriography. Peak systolic velocity values of Doppler US were significantly higher in patients with proven angiographic RAS (3.44±0.66 m/s) than in hypertensive patients with normal renal arteries at angiography (0.99±0.35 m/s, P <0.0001) and normotensive healthy children (1.04±0.23 m/s, P <0.0001). With the use of multiple views, and the experience acquired with practice, false-negatives or false-positives due to the geometry of the renal artery can be avoided. Nevertheless, very distal stenosis can be missed by Doppler US. Received October 30, 1995; received in revised form April 16, 1996; accepted May 14, 1996     

The effects of extraction method on the measured tocopherol level and antioxidant activity of L. nobilis vegetative organs

Tocopherol contents of Tunisian Laurus nobilis vegetative organs were screened for antioxidant activity. Tocopherol isomers extracted by probe sonication and micro-scale saponification were analysed by reversed-phase high performance liquid chromatography (RP-HPLC) with UV detection to determine the optimum extraction method. Total phenolic, flavonoid and proanthocyanidin contents were determined spectrophotometrically. Significant variations in the amounts of α-, γ- and δ-tocopherols were observed with the two different extraction methods as well as with different plant parts. Leaf extract contained the highest amount of α-tocopherol (139 mg/100 g fresh weight), but root extract contained the highest content of flavonoids (11.12 mg catechin equivalents (CE)/g dry weight or DW), total phenolics (55.45 ± 2.9 mg GAE/g DW) and condensed tannins (9.76 ± 0.1 mg CE/g DW). Acetonic extract of laurel leaf exhibited the highest antioxidant activity response to lipid peroxidation in the β-carotene-linoleic acid system, which may have been due to the high content of α-tocopherol. These findings suggest that laurel leaf may be a source of natural α-tocopherol and that it may be increasingly important for human consumption, as well as for the agro-food, cosmetic and pharmaceutical industries.     

Multicenter prospective study of children with sickle cell disease: radiographic and psychometric correlation

After obtaining familial informed consent, between January 1996 and July 1997, 173 children (5 to 15 years old) with sickle cell disease were enrolled in a prospective multicenter study using blood screening, transcranial Doppler ultrasonography (n = 143), cerebral magnetic resonance imaging (n = 144), and neuropsychologic performance evaluation (n = 156) (Wechsler Intelligence tests WISC-III, WIPPSI-R), which were also performed in 76 sibling controls (5 to 15 years old). Among the 173 patients with sickle cell disease (155 homozygous for hemoglobin SS, 8 sickle cell beta0 thalassemia, 3 sickle cell beta+ thalassemia, 7 sickle cell hemoglobin C disease SC), 12 (6.9%) had a history of overt stroke, and the incidence of abnormal transcranial Doppler ultrasonography (defined as mean middle cerebral artery velocity > 200 cm/sec or absent) was 8.4% in the overall study population and 9.6% in patients with homozygous sickle cell anemia The silent stroke rate was 15%. Significantly impaired cognitive functioning was observed in sickle cell disease patients with a history of stroke (Performance IQ and Full Scale IQ), but also in patients with silent strokes (Similarities, Vocabulary, and Verbal Comprehension). However, infarcts on magnetic resonance imaging were not the only factors of cognitive deficit: Verbal IQ, Performance IQ, and Full Scale IQ were strongly impaired in patients with severe chronic anemia (hematocrit < or = 20%) and in those with thrombocytosis (platelets > 500 x 10(9)/L). Multivariate logistic regression analysis showed that abnormal magnetic resonance imaging (odds ratio [OR] = 2.76) (P = .047), hematocrit < or =20% (OR = 5.85) (P = .005), and platelets > 500 x 10(9)/L (OR = 3.99) (P = .004) were independent factors of cognitive deficiency (Full Scale IQ < 75) in sickle cell disease patients. The unfavorable effect of low hematocrit has already been suggested, but this is the first report concerning an effect of thrombocytosis and showing that silent stroke alone is not a factor of cognitive deficit when not associated with low hematocrit or thrombocytosis. The effect of hydroxyurea, which is known to increase hematocrit and decrease platelet count, on cognitive functioning of sickle cell patients should be evaluated prospectively.     

Chordoma of the base of skull. Apropos of 3 cases]

The authors report 3 cases of skull base chordomas. In 2 cases, skull radiographies and computed tomography found lytic lesions of sphenoid and clivus, with calcifications into the tumors. In the third case, radiological findings suggest a naso pharynx tumor.     

Hair growth regulation by the extract of aromatic plant <Emphasis Type="Italic">Erica multiflora</Emphasis>

Hair growth problems can affect human physical and mental health and are of particular relevance during the aging process. In an effort to resolve such problems, we attempted to find plants having hair growth regulation activity and thus collected plant extracts from Tunisia for bioprospecting purposes. Among them, we investigated the Erica multiflora extract to evaluate the hair growth promotion activity by using the MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide) assay and cell cycle assay on human dermal papilla cells in vitro and an administration assay on mouse dorsal skin in vivo. The results showed that the Erica multiflora extract promotes dermal papilla cell growth and cell cycle with high activity, and induced hair growth in vivo by induction of anagen phase from telogen phase.