Vertebral compression fracture as a presenting feature of acute lymphoblastic leukemia in children

Twenty-four (1.6%) of 1466 children with acute lymphoblastic leukemia (ALL) treated at St. Jude Children's Research Hospital had vertebral compression fractures at diagnosis. When compared with patients without this complication, they were more likely to have good prognostic features, including a leukocyte count of greater than 25 X 10(9)/l, a leukemic cell DNA index of greater than 1.15, and hyperdiploidy (greater than 50 chromosomes). Complete remission of ALL was induced in all patients, and symptoms of vertebral compression fractures abated following antileukemia therapy. Although the diagnosis of ALL was delayed for some patients because this unusual presenting complication was not recognized as such, their treatment outcome was as good as that for other children with "standard-risk" ALL.     

Caffeine reverses age-related deficits in olfactory discrimination and social recognition memory in rats. Involvement of adenosine A1 and A2A receptors

Caffeine, a non-selective adenosine receptor antagonist, has been suggested as a potential drug to counteract age-related cognitive decline since critical changes in adenosinergic neurotransmission occur with aging. In the present study, olfactory discrimination and short-term social memory of 3, 6, 12 and 18 month-old rats were assessed with the olfactory discrimination and social recognition tasks, respectively. The actions of caffeine (3.0, 10.0 and 30.0 mg/kg, i.p.), the A1 receptor antagonist DPCPX (1.0 and 3.0 mg/kg, i.p.) and the A2A receptor antagonist ZM241385 (0.5 and 1.0 mg/kg, i.p.) in relation to age-related effects on olfactory functions were also studied. The 12 and 18 month-old rats exhibited significantly impaired performance in both models, demonstrating deficits in their odor discrimination and in their ability to recognize a juvenile rat after a short period of time. Acute treatment with caffeine or ZM241385, but not with DPCPX, reversed these age-related olfactory deficits. The present results suggest the participation of adenosine receptors in the control of olfactory functions and confirm the potential of caffeine for the treatment of aged-related cognitive decline.     

Sputum Cytokine Levels in Patients with Pulmonary Tuberculosis as Early Markers of Mycobacterial Clearance

Sputum and serum from patients with active pulmonary tuberculosis (TB), healthy purified protein derivative-positive adults, and patients with bacterial pneumonia were collected to simultaneously assess local immunity in the lungs and peripheral blood. To determine whether cytokine profiles in sputum from TB patients and control subjects were a reflection of its cellular composition, cytospin slides were prepared in parallel and assessed for the presence of relative proportions of epithelial cells, neutrophils, macrophages, and T cells. Gamma interferon (IFN-γ) in sputum from TB patients was markedly elevated over levels for both control groups. With anti-TB therapy, IFN-γ levels in sputum from TB patients decreased rapidly and by week 4 of treatment were comparable to those in sputum from controls. Further, IFN-γ levels in sputum closely followed mycobacterial clearance. Although detected at fourfold-lower levels, IFN-γ immunoreactivities in serum followed kinetics in sputum. TNF-α, interleukin 8 (IL-8) and IL-6 also were readily detected in sputum from TB patients at baseline and responded to anti-TB therapy. In contrast to IFN-γ, however, TNF-α and IL-8 levels also were elevated in sputum from pneumonia controls. These data indicate that sputum cytokines correlate with disease activity during active TB of the lung and may serve as potential early markers for sputum conversion and response to anti-TB therapy.     

Decreased availability of intestinal dopamine in transmural colitis may relate to inhibitory effects of interferon-gamma upon L-DOPA uptake

AIMS: The present study aimed to evaluate the relationship between intestinal inflammation, interferon-gamma (IFN-gamma) levels and intestinal levels of dopamine, its precursor l-3,4-dihydroxyphenylalanine (L-DOPA), and the activity of aromatic L-amino acid decarboxylase (AADC) activity along the digestive tract in a rat experimental model of colitis. METHODS: Colitis was induced by rectal administration of 2,4,6-trinitrobenzene sulphonic acid (TNBS). Catechol derivatives were assayed by means of HPLC-EC. RESULTS: It is shown that dopamine and noradrenaline levels in the distal colon (inflamed mucosa), but not in the ileum (non-inflamed mucosa), of TNBS-treated rats were markedly lower than in control animals. A slight decrease in L-DOPA tissue levels, no changes in AADC activity and an increase in plasma IFN-gamma levels accompanied this decrease in dopamine levels. Exposure of Caco-2 cells, a human intestinal epithelial cell line, to human IFN-gamma resulted in a concentration-dependent and long-lasting inhibition of L-DOPA uptake, which most likely explains the decrease in dopamine levels in the inflamed mucosa. CONCLUSION: Changes in tissue levels of noradrenaline and dopamine in experimental colitis in the rat follow a similar pattern to that observed in patients with Crohn's disease and ulcerative colitis. In this model of experimental colitis, the decrease in dopamine levels is most likely explained by the inhibitory effect of IFN-gamma on L-DOPA uptake by intestinal epithelial cells.     

Group‐specific component (GC) in curiaú and pacoval,two african‐derived brazilian populations

The group‐specific component (GC) system is of interest in anthropological genetic studies because the distribution of its subtypes distinguishes among major ethnic groups. The GC system was analyzed in Curiaú and Pacoval, two remnant Quilombo populations (African‐derived populations) from the Brazilian Amazon. There was no significant statistical difference in allelic frequencies between the two populations or between them and three other African‐derived Brazilian populations (Mimbó, Sítio Velho, and Gaucinha in Northeastern Brazil). These populations share similarities among themselves and with African populations (high frequencies of GC*1F and lower frequencies of GC*1S), which may reflect the influence of a high level of African contribution to their formation, but there is a clear difference between them and Europeans and South American Indians. It is suggested that the GC system is a useful marker for studying relationships between single populations and major ethnic groups, but does not discriminate between populations which share the same parental stock. Am. J. Hum. Biol. 13:718–720, 2001. © 2001 Wiley‐Liss, Inc.     

Multiclonal Leishmania braziliensis population structure and its clinical implication in a region of endemicity for American tegumentary leishmaniasis

In Corte de Pedra (CP), northeastern Brazil, Leishmania braziliensis causes three distinct forms of American tegumentary leishmaniasis (ATL). To test the hypothesis that strain polymorphism may be involved in this disease spectrum and accurately characterize the parasite population structure in CP, we compared one L. major, two non-CP L. braziliensis, one CP L. amazonensis, and 45 CP L. braziliensis isolates, obtained over a 10-year period from localized cutaneous, mucosal, and disseminated leishmaniasis patients, with randomly amplified polymorphic DNA (RAPD). Electrophoretic profiles were mostly unique across species. All typing protocols revealed polymorphism among the 45 CP L. braziliensis isolates, which displayed eight different RAPD patterns and greater than 80% overall fingerprint identity, attesting to the adequacy of the tools to assess strain variability in CP's geographically limited population of parasites. The dendrogram based on the sum of RAPD profiles of each isolate unveiled nine discrete typing units clustered into five clades. Global positioning showed extensive overlap of these clades in CP, precluding geographic sequestration as the mechanism of the observed structuralization. Finally, all forms of ATL presented a statistically significant difference in their frequencies among the clades, suggesting that L. braziliensis genotypes may be accompanied by specific disease manifestation after infection.     

Sporogony and experimental transmission of Babesia equi by Boophilus microplus

The development of Babesia equi in salivary glands of adult female Boophilus microplus was observed under a light microscope using semithin sections stained with toluidine blue. Engorged nymphs were obtained from splenectomized foals experimentally infected with B. equi. As adults, they were then fed on rabbits for 5 days and the salivary glands of manually collected individuals were removed at intervals of 24 h. Sporozoites were found in type III granular acini cells between the 2nd and 5th days following feeding on the rabbits. Sporoblasts and sporozoites were observed in the same or adjacent acini cells in all the glands examined. The formation of the sporozoites occurred following the multiple division of the sporoblasts through a process of radial budding from the periphery of bodies resulting from multiple fission. Sporozoites were detected in smears of adult males stained with Giemsa, between the 2nd and 5th days following feeding by the ticks. Adults of B. microplus, fed during the nymphal phase on foals with patent parasitemia, transmitted sporozoites of B. equi to a splenectomized foal. The role of B. microplus in the transmission and epidemiology of B. equi is discussed. Received: 16 June 1997 / Accepted: 2 September 1997