Cognitive consequences of early phase of literacy.

The effect of the degree of illiteracy (complete or incomplete) on phonological skills, verbal and visual memory and visuospatial skills is examined in 97 normal Brazilian adults who considered themselves illiterate, and 41 Brazilian school children aged 7 to 8 years, either nonreaders or beginning readers. Similar literacy effects were observed in children and in adults. Tasks involving phonological awareness and visual recognition memory of nonsense figures distinguish the best nonreaders and beginning readers. Children performed better than adults at oral repetition of short items and figure recall, and adults better than children at semantic verbal fluency, digit span, and word list recall. A principal component analysis of the correlations between tasks showed that phonological awareness/reading, phonological memory/oral repetition, and semantic verbal memory/fluency tasks, generated different components. The respective role of culturally based preschool activities and literacy on the cognitive functions that are explored in this study is discussed.     

Influence of Adrenal Glands on the Modulation of Prolactin Gene Expression by the Endogenous Benzodiazepine Ligand Octadecaneuropeptide in the Male Rat Pituitary Gland

Recently, an 86-amino acid polypeptide with high affinity for diazepam binding sites, termed diazepam-binding inhibitor (DBI), has been found in the rat brain. DBI, as well as a peptide derived from DBI, the octadecaneuropeptide DBI[33–50] (ODN), interacts with the GABA_A receptor complex. To investigate the role of these endogenous ligands for GABA_A receptors on prolactin gene expression, we studied the effects of acute intracerebroventricular administration (4  h before sacrifice) of ODN on prolactin mRNA levels in the male rat. Because, in some neuropeptidergic systems, glucocorticoids play a role in the response to ODN, we also studied the influence of adrenal glands and the effect of dexamethasone administration in the response of prolactin gene expression to ODN. ODN injection produced an increase in prolactin mRNA levels. Adrenalectomy performed 5 days before sacrifice resulted in an increase in prolactin gene expression and also potentiated the stimulating effect of ODN. Because castration has been shown to decrease prolactin gene expression in the male rat, we used castrated and adrenalectomized animals to study the role of dexamethasone in the response of lactotrophs to ODN. In these steroid-deprived animals, dexamethasone treatment (for 4 days) decreased prolactin mRNA levels but did not modify the response to ODN. These data indicate that an endogenous neuropeptide interacting with the GABA_A receptor complex can stimulate prolactin gene expression and suggest that the adrenal glands may produce factor(s) capable of decreasing prolactin mRNA. On the other hand, it does not appear that glucocorticoid hormones play a role in the effect of ODN on lactotroph activity.     

Prominent intrasinusoidal infiltration of the bone marrow by mantle cell lymphoma

Intrasinusoidal infiltration of bone marrow (BM) may accompany several malignant lymphoproliferative disorders. In small B-cell lymphomas, this pattern is considered specific for splenic marginal zone lymphoma (SMZL) when exclusive or prominent, although it may occur in other subtypes of non-Hodgkin's lymphomas (NHLs) as a minor feature. Here we report 2 cases of mantle cell lymphoma (MCL) with a prominent intrasinusoidal BM infiltration pattern. Both patients presented with massive splenomegaly and peripheral blood involvement characterized by markedly atypical lymphocytes, but no lymphadenopathy. The cytological features and the phenotype of the lymphoma cells were diagnostic of MCL. The malignant B cells showed coexpression of B-cell markers (CD20+ and CD79a+), CD5 antigen, and cyclin D1 by immunohistochemistry. We discuss the specificity of an intrasinusoidal growth pattern in the bone marrow, emphasizing the importance of using a broader immunohistochemical panel in the differential diagnosis of intrasinusoidal BM infiltration by NHL.     

Dilution assessment of cervicovaginal secretions obtained by vaginal washing for immunological assays.

Local immunological defense mechanisms in the cervicovaginal mucosa currently remain incompletely defined, especially from a quantitative point of view. Addition of an inert substance, lithium chloride (LiCl), into the washing buffer used to carry out the vaginal washing for collecting cervicovaginal secretions and measurement of its concentration with a flame absorption spectrophotometer, before and after the specimen is sampled, permits the quantification of the volume of cervicovaginal secretions collected and the approximation of the dilution factor of a soluble component introduced by the washing. Lithium, at a concentration of 10 mM, gives the best precision of measurement and has no effect on the results of the immunoassays. In a population of 27 nonpregnant women (age range, 18 to 45 years), the volume of cervicovaginal secretions collected by vaginal washing with 3 ml of LiCl-phosphate-buffered saline was 12% +/- 3.2% (mean +/- standard deviation) of the total volume and showed large interindividual variations (range, 5.6 to 18.8%); the mean dilution factor of a soluble component from the vaginal secretions was 9.9% +/- 2.8% (range, 6.3 to 18.8%). According to the date of the menstrual cycle, the mean volume of collected cervicovaginal secretions was significantly increased in the luteal phase in comparison with the follicular phase; conversely, the mean dilution factor of a soluble component was more important in the follicular than in the luteal phase. These features strengthen the need to quantify accurately the dilution factor introduced by vaginal washing when studying cervicovaginal immunity.     

Requirement for tumor necrosis factor receptor 2 expression on vascular cells to induce experimental cerebral malaria

Using tumor necrosis factor receptor type 2 (TNFR2)-deficient mice and generating bone marrow chimeras which express TNFR2 on either hematopoietic or nonhematopoietic cells, we demonstrated the requirement for TNFR2 expression on tissue cells to induce lethal cerebral malaria. Thus, TNFR2 on the brain vasculature mediates tumor necrosis factor-induced neurovascular lesions in experimental cerebral malaria.     

Genotypic analysis of sequential genital herpes simplex virus type 1 (HSV-1) isolates of patients with recurrent HSV-1 associated genital herpes

Clinical recurrences of Herpes simplex virus type 1 (HSV-1)-associated genital herpes are thought to be caused by reactivation of latent endogenous HSV-1. However, the possibility of reinfection with exogenous HSV-1 cannot be excluded. This study aimed to determine the incidence of genital HSV-1 superinfection in patients by investigating the genotype of sequential HSV-1 isolates obtained from the same anatomical site of patients with clinical recurrences of genital HSV-1 recurrent genital herpes. Sequential genital HSV-1 isolates were genotyped by PCR amplification of the hypervariable regions located within the HSV-1 genes US1 and US12. Whereas the sequential HSV-1 isolates in 11 of the 13 patients studied had the same genotypes, the sequential isolates of 2 patients showed a different genotype. The data suggest that HSV-1-induced recurrent genital herpes can be associated with genital reinfection with an exogenous HSV-1 strain.     

Ultrastructure du fuseau neuro-musculaire chez l'homme

Summary The ultrastructure of the muscle spindles has been studied in human lumbrical muscles. The findings have been compared with the morphology of muscle spindles of rat and sheep examined with light and electron microscopy. The study is based on cross and longitudinal sections of the entire muscle spindle obtained by dissection. The different components of the spindle are described with special reference to the nuclear bag and nuclear chain fibres. These nuclei have been examined in human adult and newborn material and compared to the animal ones. ADN measurements revealed that although there are morphological differences between the two kinds of nuclei in human newborn spindles, the amount of ADN is the same as well in the nuclear bag as in the nuclear chain nuclei. Special attention is also given to the sensory and motor endings in the muscle spindles and to the presence of Pacinian corpuscules in these receptors. Finally two kinds of leptomeric organelles are described in human material.