Lymphoma associated bone marrow necrosis with raised anticardiolipin antibody.

A case of high grade B cell lymphoma presented with bone marrow necrosis, followed by development of extensive marrow fibrosis, the evolution of which was documented by serial magnetic resonance imaging and bone marrow trephine histology. A markedly raised anticardiolipin antibody titre at diagnosis suggests that lymphoma associated antiphospholipid syndrome may have contributed to the aetiology of the bone marrow necrosis.     

Patterns of CD16 and CD56 expression in persistent expansions of CD3+NKa+ lymphocytes are predictive for clonal T-cell receptor gene rearrangements

Phenotypic characteristics, and correlations between the expression of membrane NK-associated (NKa) determinants (CD11b, CD16, CD56 and CD57) and T cell receptor (TCR) genotypic patterns, were examined in 25 patients with persistent (greater than 6 months) expansions of CD3+WT31+NKa+ (CD8+ and CD8dim+) lymphocytes. These studies showed that distinct NKa phenotypic profiles were restricted to cases with rearranged TCR configurations and that clonal CD3+NKa+ components could be predicted in most cases by assessing relationships between membrane CD16 and CD56 expression. For all normal NKa subpopulations, there was a high correlation (P less than 0.0001; n = 31) between the expression of these two membrane determinants. Markedly increased CD16 expression by CD3+NKa+ cells, in relation to CD56 (i.e. a high CD16:CD56 ratio), was found exclusively in cases with rearranged TCR (13/16 cases); 2/3 of the remaining cases showing significantly reduced CD16:CD56 ratios and high (greater than 2.0) CD3+CD56+ absolute numbers. In contrast, 7/9 of the germline TCR cases had a normal CD16:CD56 ratio and 2/9 a decreased ratio with low (less than 1.0) CD3+CD56+ absolute numbers. A high ratio of CD16:CD56 expression by CD3+NKa+ lymphocytes was therefore informative for 82% of TCR rearrangements in this series; and analysis of CD16 and CD56 expression was predictive for germline and rearranged TCR configurations in 24/25 persistent CD3+NKa+ expansions.     

Parapharyngeal space melioidosis in a diabetic

Pseudomonas pseudomallei, a gram negative organism causing melioidosis, is found in tropical and subtropical regions. It may manifest as a pulmonary lesion, osteomyelitis, soft tissue abscesses, abscesses in various organs or in septicaemic form. Melioidosis of the parapharyngeal space has not been reported so far. A case of melioidosis of the parapharyngeal space which was successfully treated by drainage and prolonged antibiotic therapy is reported here. Melioidosis should be suspected in severe forms of deep neck space infection, especially if the patient comes from an endemic area.     

Parental age in Indian patients with sporadic hereditary retinoblastoma

There is a consistent correlation between sporadic hereditary retinoblastoma and parental age. It has been proven beyond doubt that the birth rank is correlated with parental age. In the present study, a test for the effect of birth rank was performed in order to assess the risk of developing retinoblastoma with increased parental age. The study of the effect of birth rank showed a significant association between sporadic retinoblastoma (bilateral and unilateral) and late para, indicating that fresh germline mutations must have taken place in some of the sporadic cases. An investigation of the effect of birth rank on familial cases, obtained from published papers and our own series, showed that familial retinoblastoma is significantly associated with early para, suggesting early parental age. Further analysis of the mean paternal and maternal ages of sporadic cases (bilateral and unilateral) showed that the mean paternal age of sporadic bilateral (sporadic hereditary) cases was higher than that of sporadic unilateral cases (p<0.05). No such correlation was seen with mean maternal age. Thus, the present study shows that a high paternal age may be associated with sporadic bilateral (sporadic hereditary) retinoblastoma.     

Conservation of the RB1 gene in human and primates

Mutations in the RB1 gene are associated with retinoblastoma, which has served as an important model for understanding hereditary predisposition to cancer. Despite the great scrutiny that RB1 has enjoyed as the prototypical tumor suppressor gene, it has never been the object of a comprehensive survey of sequence variation in diverse human populations and primates. Therefore, we analyzed the coding (2,787 bp) and adjacent intronic and untranslated (7,313 bp) sequences of RB1 in 137 individuals from a wide range of ethnicities, including 19 Asian Indian hereditary retinoblastoma cases, and five primate species. Aside from nine apparently disease-associated mutations, 52 variants were identified. They included six singleton, coding variants that comprised five amino acid replacements and one silent site. Nucleotide diversity of the coding region (pi=0.0763+/-1.35 x 10(-4)) was 52 times lower than that of the noncoding regions (pi=3.93+/-5.26 x 10(-4)), indicative of significant sequence conservation. The occurrence of purifying selection was corroborated by phylogeny-based maximum likelihood analysis of the RB1 sequences of human and five primates, which yielded an estimated ratio of replacement to silent substitutions (omega) of 0.095 across all lineages. RB1 displayed extensive linkage disequilibrium over 174 kb, and only four unique recombination events, two in Africa and one each in Europe and Southwest Asia, were observed. Using a parsimony approach, 15 haplotypes could be inferred. Ten were found in Africa, though only 12.4% of the 274 chromosomes screened were of African origin. In non-Africans, a single haplotype accounted for from 63 to 84% of all chromosomes, most likely the consequence of natural selection and a significant bottleneck in effective population size during the colonization of the non-African continents.     

Defining remission by cut off score on the MADRS: selecting the optimal value

BACKGROUND: Remission from major depression may be conceptualised in terms of a cut-off score on an appropriate rating scale. Candidate values proposed hitherto have not been directly validated. METHOD: The relationship between The Clinical Global Impression Scale for Severity (CGI-S) and the Montgomery-Asberg Depression Rating Scale (MADRS) was explored in 684 major depressed patients (1114 observations). The value on the MADRS which had greatest concordance with remission, as defined by the CGI-S, was computed using two models. Concordance between clinician and patient judgements of global illness were also compared. RESULTS AND CONCLUSION: The two models yielded optimal definitions of remission of <9 and <10 on the MADRS. Either value offers a workable operationalisation of remission and there is little to choose between them. CLINICAL RELEVANCE: The data confirm that MADRS <10 should provide the clinician with a valid, and reasonably objectifiable, target for remission