Epstein-Barr virus BZLF1 gene polymorphisms: malignancy related or geographically distributed variants?

The ubiquitous Epstein-Barr virus (EBV) is related to the development of several lymphoid and epithelial malignancies and is also the aetiological agent for infectious mononucleosis (IM). BZLF1, an immediate early gene, plays a key role in modulating the switch from latency to lytic replication, hence enabling viral propagation. Polymorphic variations in the coded protein have been studied in other geographical regions in a search for viral factors that are inherent to malignancies and differ from those present in benign infections. In the present study, in samples of paediatric patients with benign IM and paediatric patients with malignant lymphomas, we detected previously described sequence variations as well as distinctive sequence polymorphisms from our region. By means of phylogenetic reconstruction, we characterized new phylogenetically distinct variants. Moreover, we described an association between specific variants and the studied pathologies in our region, particularly variant BZLF1-A2 with lymphomas and BZLF1-C with IM. Additionally, length polymorphisms within intron 1 were also assessed and compared between pathologies resulting in an association between 29-bp repeated units and lymphomas. In conclusion, this is the first report to characterize BZLF1 gene polymorphisms in paediatric patients from our geographical region and to suggest the association of these polymorphisms with malignant lymphomas.

Epstein Barr virus in relation to apoptosis markers and patients' outcome in pediatric B-cell non-Hodgkin lymphoma.

In this study, we investigated Epstein Barr virus (EBV) presence, associated to proliferation and apoptosis proteins in pediatric B-cell Non-Hodgkin lymphoma (B-NHL). EBERs, Ki67, active caspase 3, Bax and Bcl2 were analyzed on B-NHL tissue from 40 patients. Forty percent showed EBV expression, significantly higher among patients ⩽10years (P=0.027), and associated with immunosuppression (P=0.020), but not associated apotosis markers. However, EBV was associated with a worse event-free survival (P=0.016), particularly under immunosuppression. Even though EBV did not seem to alter apoptotic pathways, it exhibited survival disadvantage and could be an important cofactor in B-cell lymphomagenesis in younger children.

Vulvar plasmablastic lymphoma in a HIV-positive child: a novel extraoral localisation.

Plasmablastic lymphoma (PBL) has been characterised by the World Health Organization as a new entity. This report describes an unusual case of PBL in a 3-year-old HIV-infected patient showing a cutaneous vulvar lesion with 9 months of evolution and prolapsed vulvovaginal mucosa. Histopathological examination of a biopsy sample showed diffuse submucosal infiltration by large cells with a cohesive growth pattern, and round and vesicular nuclei with fine chromatin centrally or eccentrically placed with one or more prominent nucleoli. Immunohistochemical staining in neoplastic cells was positive for multiple melanoma oncogene (MUM1), CD138, CD45 and epithelial membrane antigen (EMA). The diagnosis was PBL, stage III. Epstein-Barr virus (EBV) expression was positive by EBV encoded RNAs in situ hybridisation. This is believed to be the third case of paediatric HIV-associated PBL reported in the literature, and the first with vulvar localisation, which is a new anatomical location for this entity.

Effect of one year residence in Antarctica on bone mineral metabolism and body composition.

OBJECTIVE: To evaluate the changes of the biochemical parameters of mineral metabolism and to assess the effect of these changes on the bone mass of young healthy men who voluntarily lived in the Antarctic Continent for one year. DESIGN: Lumbar spine and whole body bone mineral density (BMD) were measured pre- and post-campaign (14 months later). Serum and urinary biochemical parameters were measured every two months. Serum levels of calcium, phosphate, total alkaline phosphatase, parathormone (PTH) and 25-hydroxyvitamin D (250HD) were determined in blood fasting samples; and hydroxyproline, calcium and creatinine in 2 h fasting urine. The subjects received a dose of 100 i.u./d of vitamin D during May after obtaining the samples and then an average of 125 i.u./d from July to January. SUBJECTS: Seventeen healthy volunteers, who left Buenos Aires during the 1992 summer: ten arrived in the Belgrano II Base at the end of January and the other seven arrived in San Martín in March and stayed there up to summer 1993. RESULTS: BMD increased in lumbar spine (L2-L4), total body and the subarea of the legs but there were no differences between the pre- and post-campaign values in arms and pelvis. The percentage of fat mass decreased significantly after 1 y of residence in Antarctica, in comparison to the basal values. Most biochemical parameters remained unaltered and within the normal range during the whole study. PTH showed a nadir in March (end of the summer) when compared to initial levels (73.0 +/- 28.2 vs 39.9 +/- 32.7 pg/ml, P < 0.05), and recovered its initial value in spring. Calcium levels showed a significant decrease in March (9.5 +/- 0.4 vs 8.5 +/- 1.0 mg%, P < 0.01). 25OHD levels began to decrease in March (24.7 +/- 6.4 vs 18.7 +/- 5.3 ng/ml), reaching a minimum value whose difference approached statistical significance during the winter period (July: 16.4 +/- 8.2 ml, 0.05 < P < 0.06). No significant changes in serum phosphate, total alkaline phosphatase, urinary hydroxyproline/creatinine and calcium/creatinine ratios were found through the year. CONCLUSIONS: 25OHD levels decreased in autumn and winter (nadir in July) and recovered the initial levels by the end of the campaign. An unexplained marked diminution in PTH and serum calcium was found at the beginning of the campaign. In spite of the low vitamin D levels, bone mass in this group of young healthy men increased, probably because of their intense physical activity.

Effect of treatment on bone mass, mineral metabolism, and body composition in untreated celiac disease patients.

BACKGROUND/AIMS: Osteopenia is a common complication of celiac disease. The aims of this study were to evaluate whether treatment produces bone remineralization and whether calcium and vitamin D supplementation are necessary to reduce osteopenia. METHODS: Bone mineral density and biochemical parameters of bone and mineral metabolism were measured in 14 newly diagnosed adult celiac disease patients. All patients were treated with a gluten-free diet and were randomized to receive diet only (n = 7) or diet plus calcium (1.0 g/day) and vitamin D (32,000 IU/wk) supplementation (n = 7). Bone density was measured at baseline and at 6 and 12 months of follow-up. Tests for biochemical determinations were repeated every 3 months. RESULTS: At diagnosis, 11 patients had evidence of osteopenia (> 1 SD below normality) in the spine and total skeleton. After 12 months of gluten restriction, overall bone mass had increased 5.0% (p < 0.01) in the lumbar spine and 5.0% (p < 0.002) in the total skeleton. When one only considers those 11 patients who strictly followed gluten restriction, bone density increased 8.4% in the lumbar spine and 7.7% in the total skeleton. Remineralization occurred throughout the skeleton but was more pronounced in the axial than in the peripheral skeleton. The increase in bone mass was independent of age or menopause. Remineralization in patients treated with diet only was similar to that of patients treated with diet and supplements. Basal biochemical parameters showed a high bone turnover with secondary hyperparathyroidism. Treatment induced a decrease in bone turnover activity. However, a complete restoration of biochemical parameters was not achieved. CONCLUSIONS: Strict gluten avoidance promoted a significant increase in bone mineral density. However, values still remain markedly low after 1 yr in several patients. Although calcium and vitamin D supplementation did not provide additional benefit to that obtained by diet alone in the doses administered, our results do not preclude a possible effect of vitamin D at higher dose.

Comparative efficiency of trypticase soy agar vancomycin and Levine's media for the isolation and identification of Neisseria on tongue and saliva.

Analise comparativa da eficiencia entre dois meios de cultura para o isolamento e quantificacao de especies do genero Neisseria, isoladas da lingua e da saliva.Utilizando-se do meio T.S.A. adicionado de vancomicina (TSAV) e do meio de Levine, sao propostos padroes de coleta e manipulacao das amostras colhidas da saliva e da lingua, para o isolamento e quantificacao de especies do genero Neisseria. O meio TSAV e o mais indicado, tendo N. sicca sido isolada em 10 dos estudados.De uma forma geral, a lingua apresentou maior populacao de Neisseria do que a saliva