Genome analysis of dengue type-1 virus isolated between 1990 and 2001 in Brazil reveals a remarkable conservation of the structural proteins but amino acid differences in the non-structural proteins

We have investigated the genetic diversity of dengue type-1 (DEN-1) virus in Brazil. The full nucleotide sequences of three DEN-1 virus isolated from DEN fever (DF) and DEN hemorrhagic fever patients in northeastern Brazil in 1997 (BR/97) and one from a DF patient in the south of Brazil in 2001 (BR/01) were compared to that of the reference strain BR/90 obtained in the city of Rio de Janeiro in 1990. Sequence analysis showed that the structural proteins were remarkably conserved between all isolates. A total of 27 amino acid changes occurred throughout the non-structural proteins. Among them, nine amino acid substitutions were specific of BR/97 and BR/01 isolates, indicating that in situ evolution of these strains had occurred. Within the BR/97 and BR/01 samples, some amino acid substitutions have been previously identified in DEN-1 virus strains sequenced so far, suggesting that recombination events might have occurred.     

Effects of selective NMDA and non-NMDA blockade in the nucleus accumbens on the plus-maze test

Effect of blocking N-methyl-D-aspartic acid (NMDA) and non-NMDA-glutamatergic receptors on performance in the plus-maze was studied in male rats bilaterally cannulated into the nucleus accumbens (Acc). Rats were divided into seven groups that received either 1 microl injections of saline, (+/-)2-amino-7-phosphonoheptanoic acid (AP-7, 0.2, 0.5, or 1 microg) or 2,3 dioxo-6-nitro-1,2,3,4,tetrahydrobenzo-(f)quinoxaline-7-sulphonamide disodium (NBQX, 0.2, 0.5, or 1 microg) 15 min before testing. Time spent in open arm, time per entry, end arrivals, open, closed, and total arm entries, relationship between open-, closed-, and total arm entries, rearing, face-, head-, and body grooming, and number of fecal boli were recorded. Time spent in the open arm increased under AP-7 (0.5 and 1 microg; P<.01) and NBQX (1 microg; P<.05) treatment, whereas time per entry was increased only with AP-7 (1 microg; P<.05). Open arm entries were increased by the intermediate doses of AP-7 (0.5 microg; P<.01) and NBQX (0.5 microg; P<.05); end arrivals were increased by the intermediate dose of AP-7 (0.5 microg/1 microl, P<.05). The frequency of rearing, grooming, and closed arm entries was not affected by the treatment. We conclude that NMDA and non-NMDA-glutamatergic blockade in the Acc lead to a behavioral disinhibition of cortical influences with the median doses, but that at higher doses the blockers have an anxiolytic-like effect.     

Expression of CD4 on peripheral blood granulocytes. a novel finding in a case of myelodysplastic syndrome in association with t(5;12)

Myelodysplastic syndromes (MDS) are associated with cell maturation defects that can manifest as abnormal surface antigen expression. We describe a patient with refractory anemia with excess blasts, who presented with infection and extensive dysplastic features in peripheral blood granulocytes. The granulocytes expressed CD11b, CD13, CD15, CD33, and CD43. The granulocytes also expressed CD4 antigen. Cytogenetic analysis showed a clonal t(5;12)(q33;p13). The patient improved on antibiotics with partial improvement in the dysplastic features. However, shortly after, the patient experienced paravertebral extramedullary blast transformation followed by a leukemia phase of acute monoblastic leukemia. The patient died a few days later. This is the first report describing anomalous expression of CD4 on granulocytes in MDS. Since the breakpoint on chromosome 12 is near the CD4 gene, which is mapped to 12p12, we hypothesize that dysregulation of the CD4 gene may have occurred resulting in its persistent expression on mature and maturing granulocytes.     

Cartilage-free areas in the elbow joint of young golden retrievers

The present study describes cartilage-free areas on the ulnar trochlear notch and the humeral condyle of eight very young golden retrievers with otherwise healthy elbow joints. Remarkably, the youngest dog with full-thickness cartilage-free areas was only 8 weeks old. The younger dogs showed no macroscopic abnormalities on the locations that were affected in the older dogs. Two kinds of cartilage modifications were found. Cartilage-free areas at the edges of the articular cartilage layer were present on the humeral capitulum and on two locations of the ulna, (the medial and lateral at the base of the anconeal process, and the trochlear notch near the lateral coronoid process, which was fractured in two cases). Histological examination showed that these cartilage-free areas were filled with dense supportive tissue. Synovial cells covered this tissue as well as the surrounding hyaline cartilage. The synovial membrane covering the areas was macroscopically enlarged, but histological examination revealed no signs of inflammation. The second type of modification consisted of discoloration of the articular surface at the humeral trochlea. Histological examination revealed that in this area the articular surface was composed of fibrocartilage instead of hyaline cartilage. Apparently, there are locations within the elbow joint in which articular cartilage is not necessary for normal joint functioning. The presence of fibrocartilage on the articular surface of the humeral condyle is a surprising finding, for which no explanation has yet been found.     

Plasma cell counts on human jejunal biopsy specimens examined by immunofluorescence and immunoperoxidase techniques: a comparative study.

Ten human jejunal biopsy specimens were examined by both immunofluorescence (IF) and immunoperoxidase (IP) methods to compare both plasma cell counts and the distribution of extracellular immunoglobulins. Each specimen was cut into at least two portions, one fixed in 5% formaldehyde in phosphate-buffered saline before being snap-frozen and sectioned on a cryostat for IF, the other being fixed in half-strength Zenker and embedded in paraffin wax by standard methods for IP. Plasma cell counts were comparable in the eight biopsy specimens for which they could be estimated, geometric mean values being IgA 22.9 (IF), 19.3 (IP) and IgM 9.5 (IF), 10.6 (IP). Two specimens showing subtotal villous atrophy had too much extracellular IgA for plasma cell counts to be feasible. For these the IF methods had the advantage that the extracellular immunoglobulin was more readily distinguishable from background staining.     

The association of socioeconomic status and use of crack/cocaine with unprotected anal sex in a cohort of men who have sex with men in Rio de Janeiro, Brazil.

To evaluate the relation between illicit drug use, sexual practices, and socioeconomic status, we analyzed data from the baseline interview of a cohort of 675 men who have sex with men conducted from 1994 to 1999 in Rio de Janeiro, Brazil. Bivariate analyses of factors associated with crack/cocaine use with sex revealed that men who reported crack/cocaine use were significantly ( p <.05) more likely than men who did not report drug use to be unemployed (42.7% vs. 29.1%), to have an income of <$250 per month (70.7% vs. 60.9%), to have <8 years of education (69.5% vs. 50.9%), to report bisexual activity (81.7% vs. 41.7%), and to engage in commercial sex (72.0% vs. 37.9%). Multivariate analysis of factors associated with unprotected anal sex with casual male partners in the last 6 months demonstrated that the following variables were associated with this outcome: an income <$250 per month (adjusted odds ratio [AOR] = 1.73, 95% confidence interval [CI]: 1.04-2.87), less than 8 years of education (AOR = 2.21, CI: 1.38-3.53), a greater sense of vulnerability (AOR = 2.58, CI: 1.54-4.33), a willingness to participate in vaccine trials (AOR = 1.91, CI: 1.20-3.05), and use of crack/cocaine (AOR = 1.91, CI: 1.05-3.46). Our findings suggest that HIV prevention programs for these men need to address drug use and how drug use may influence sexual behaviors.     

Characterization of FcepsilonRI-bearing CD123 blood dendritic cell antigen-2 plasmacytoid dendritic cells in atopic dermatitis

BACKGROUND: The high-affinity receptor for IgE (FcepsilonRI) on myeloid dendritic cells has been shown to play a major role in atopic dermatitis (AD). Plasmacytoid dendritic cells (pDCs), which are instrumental in the defense of viral infections, are present in reduced amounts in the skin of patients with AD, which is characterized by a high susceptibility to viral infections. OBJECTIVE: We explored phenotypical and functional characteristics of pDC in the peripheral blood of patients with AD and healthy individuals. METHODS: Blood dendritic cell antigen-2+CD123+ pDCs were enriched from the peripheral blood of patients with AD and studied in functional assays. RESULTS: Skin-homing molecules such as cutaneous lymphocyte antigen and L-selectin CD62L were expressed in lower levels on pDCs of patients with AD. pDCs expressed high amounts of IgE-occupied FcepsilonRI. Further, FcepsilonRI aggregation on pDCs impaired the surface expression of MHC I and II, induced the production of IL-10, and enhanced the apoptosis of pDCs. Importantly, FcepsilonRI preactivated pDC produced less IFN-alpha and IFN-beta after stimulation with CpG motifs and enhanced the outcome of immune responses of the TH2 type. CONCLUSION: From these data, we conclude that FcepsilonRI-bearing pDCs from patients with AD (1) are different from pDCs of healthy individuals, (2) might be important in the pathophysiology of AD, and (3) contribute to the enhanced susceptibility of patients with AD to viral infections.