Lymph node infarction – a rare complication associated with disseminated intra vascular coagulation in a case of dengue fever

Background  

Lymph node infarction is known to occur in association with many non-neoplastic and neoplastic conditions however its occurrence in association with DIC is not reported hitherto in the literature.     

Bone marrow as a home of heterogenous populations of nonhematopoietic stem cells.

Evidence is presented that bone marrow (BM) in addition to CD45(positive) hematopoietic stem cells contains a rare population of heterogenous CD45(negative) nonhematopoietic tissue committed stem cells (TCSC). These nonhematopoietic TCSC (i) are enriched in population of CXCR4(+) CD34(+) AC133(+) lin(-) CD45(-) and CXCR4(+) Sca-1(+) lin(-) CD45(-) in humans and mice, respectively, (ii) display several markers of pluripotent stem cells (PSC) and (iii) as we envision are deposited in BM early in development. Thus, since BM contains versatile nonhematopoietic stem cells, previous studies on plasticity trans-dedifferentiation of BM-derived hematopoietic stem cells (HSC) that did not include proper controls to exclude this possibility could lead to wrong interpretations. Therefore, in this spotlight review we present this alternative explanation of 'plasticity' of BM-derived stem cells based on the assumption that BM stem cells are heterogenous. We also discuss a potential relationship of TCSC/PSC identified by us with other BM-derived CD45(negative) nonhematopoietic stem cells that were recently identified by other investigators (eg MSC, MAPC, USSC and MIAMI cells). Finally, we discuss perspectives and pitfalls in potential application of these cells in regenerative medicine.     

Eleven novel mutations in the factor VIII gene from Brazilian hemophilia A patients

The molecular characterization of the mutations in hemophilia A patients is hampered by the large size of the factor VIII gene and the great heterogeneity of mutations. In this study, we have performed a protocol involving multiplex polymerase chain reaction in which 19 exons were amplified in four different combinations followed by nonradioactive single-strand conformational polymorphism (SSCP) to screen for mutations. Southern blotting was used to detect inversion of the factor VIII gene resulting from recombination between copies of the gene A (F8A) located in intron 22 of the factor VIII gene and two copies close telomeric region of X chromosome. Forty-two hemophilia A patients (21 with severe and 21 with mild-to-moderate disease) were studied. The inversion of factor VIII occurred in 13 of 21 patients affected by severe hemophilia A. One patient showed a large extra band in addition to the three bands observed after Southern blotting with the F8A probe. An abnormal electrophoretic pattern of SSCP was detected in 85% and 50% of the patients affected by mild-to-moderate and severe disease, respectively. Sixteen different mutations were identified. Eleven mutations were novel and comprised 9 point mutations and 2 small deletions. This study shows that the methodology used is safe and rapid and has potential for detecting almost all of the genetic defects of the studied hemophilia A patients.     

Changing relations among cognitive abilities across development: implications for measurement and research

Objective: The constructs of intelligence and executive function (EF) are commonly used in neuropsychological, cognitive, and developmental research, and in the context of clinical assessment. Yet, we have a limited understanding of the changing age-related associations among these cognitive constructs and the implications for measurement and research. The objectives of this study were to compare hypothetical models using intellectual abilities (non-age corrected scores of intelligence or IQ) and experimental measures of EF and to better understand the role of age in determining the associations between these cognitive abilities at two different periods of development. We also incorporated prediction of ADHD-related difficulties. Method: We examined intellectual abilities and EF in a typically developing child sample (N = 250) and young-adult sample (N = 329). We used confirmatory factor analysis to estimate models for each developmental period: a one-factor model of general cognitive ability and a two-factor model of intelligence and EF. ADHD-related difficulties were regressed on the factors from each model. Results: Age was more strongly related to all cognitive abilities in the child sample than in the young-adult sample. In the factor analytic models, higher amounts of cognitive test score variance were explained by both models in the child sample than in the young-adult sample. Further, in the child sample, the general cognitive ability factor (combining intellectual abilities and EF) was a significant predictor of ADHD-related difficulties, but the separate intellectual ability and EF factors were not. Conclusions: Variables highly associated with age (such as intellectual ability and EF) should not be statistically controlled when assessing cognitive constructs especially in child samples when there is rapid change in cognitive abilities.     

Switching outpatients with bipolar or schizoaffective disorders and substance abuse from their current antipsychotic to aripiprazole

OBJECTIVE: Substance abuse is extremely common in patients with bipolar disorders, although minimal data are available on the treatment of this important clinical population. Aripiprazole is an atypical antipsychotic that is approved for the treatment of mania and that has a novel mechanism of action, acting as a dopamine-2 receptor partial agonist, thereby increasing dopamine release in some parts of the brain and decreasing dopa-mine release in other brain regions. Dopamine release is implicated in substance use, and both dopaminergic agonists and antagonists have been examined for the treatment of substance abuse. To our knowledge, dopa-mine receptor partial agonists have not been investigated for treatment of substance abuse in humans. METHOD: Twenty antipsychotic-treated patients with bipolar or schizoaffective disorder and current substance abuse were switched to open-label aripipra-zole using an overlap and taper method. At baseline, diagnoses were confirmed using the Mini-International Neuropsychiatric Interview based on DSM-IV criteria. Psychiatric symptoms, side effects, and substance use and craving were assessed over 12 weeks. Psychiatric symptoms were assessed with the Hamilton Rating Scale for Depression (HAM-D), Young Mania Rating Scale (YMRS), and Brief Psychiatric Rating Scale (BPRS). Substance craving was assessed with visual analogue scales, and side effects were monitored using the Abnormal Involuntary Movement Scale, Simpson-Angus Scale, Barnes Akathisia Scale, and patient report. Study enrollment was from April 2003 to February 2004. RESULTS: Significant baseline-to-exit improvement in HAM-D (p = .002), YMRS (p = .021), and BPRS (p = .000) scores were observed without a significant change in antipsychotic-induced side effect scales. In 17 participants with current alcohol dependence, significant reductions in dollars spent on alcohol (p = .042) and alcohol craving (p = .003) were found. In 9 participants with cocaine-related disorders, significant reductions in cocaine craving (p = .014), but not use, were found. CONCLUSION: A change to aripiprazole was associated with symptomatic improvement. Limitations of the study include a small sample size, high attrition, and an open-label design. Controlled trials in dual-diagnosis patients are needed to confirm these findings.     

Leukotrienes and atherosclerosis: new roles for old mediators

Lipid mediators generated from arachidonic acid through the action of 5-lipoxygenase have been known for over two decades and are implicated in a wide variety of inflammatory disorders. G-protein-coupled receptors mediate the effects of different leukotrienes in distinct cell types. Novel cellular and molecular targets were recently discovered for these mediators, with important consequences for the function of both adaptive and innate immune systems. These studies have outlined crucial new roles for leukotrienes in the recruitment of T lymphocytes and in the development of atherosclerotic lesions, suggesting novel mechanisms for their actions. Through the development of appropriate animal models, leukotrienes are becoming renewed targets for treatment of many inflammatory diseases including atherosclerosis.