Comparison of the Bactec Peds Plus pediatric blood culture vial with Roche pediatric Septi-Chek for blood cultures from pediatric patients.

Equal volumes of blood from 4,112 blood cultures were inoculated into one Bactec Peds Plus bottle and one Roche Septi-Chek bottle. There were no significant differences in the recoveries of bloodstream pathogens. Initial detection occurred earlier with Bactec Peds Plus, while growth on solid media occurred earlier with Roche Septi-Chek.     

Comparison of rapid,automated ribotyping and DNA macrorestriction analysis of Burkholderia pseudomallei

An automated ribotyping device (RiboPrinter) was used to determine the ribotypes of a collection of Burkholderia pseudomallei isolates. In a preliminary evaluation with the restriction enzymes BamHI and EcoRI, the protocol with EcoRI was more discriminating. The reproducibilities of the ribotypes obtained with EcoRI (EcoRI ribotypes) were determined by testing three levels of bacterial loads. The performance of the manufacturer's software was assessed by comparing the machine-optimized ribotypes with the type determined from the original gel image analyzed with Bionumerics software. The library of B. pseudomallei EcoRI ribotypes was then compared with the ribotypes obtained by DNA macrorestriction analysis of XbaI digests by pulsed-field gel electrophoresis. The typeability of B. pseudomallei by EcoRI ribotyping was 100%, and the discrimination index was 0.94. The slightly greater discrimination provided by DNA macrorestriction analysis (0.96) was achieved at the expense of a significantly longer processing time of 6 days, although the method was only half the cost of automated ribotyping. Typeability by macrorestriction analysis was lower (97%) unless a thiourea step was added to neutralize the action of Tris-dependent endonucleases. The digital record of B. pseudomallei isolates analyzed thus far provides a useful resource for future epidemiological studies and will help shorten the response time in the event of a further melioidosis outbreak or the deliberate release of B. pseudomallei as a biohazard.     

Influence of visual experience on developmental shift from long-term depression to long-term potentiation in the rat medial vestibular nuclei

The influence of visual experience deprivation on changes in synaptic plasticity during postnatal development was studied in the ventral part of the rat medial vestibular nuclei (vMVN). We analysed the differences in the occurrence, expressed as a percentage, of long-term depression (LTD) and long-term potentiation (LTP) induced by high frequency stimulation (HFS) of the primary vestibular afferents in rats reared in the light (LR) and those in the dark (DR). In LR rats, HFS only induced LTD in the early stages of development, but the occurrence of LTD progressively decreased to zero before their eyes opened, while that of LTP enhanced from zero to about 50%. Once the rats' eyes had opened, LTD was no longer inducible while LTP occurrence gradually reached the normal adult value (70%). In DR rats, a similar shift from LTD to LTP was observed before their eyes opened, showing only a slightly slower LTD decay and LTP growth, and the LTD annulment was delayed by 1 day. By contrast, the time courses of LTD and LTP development in DR and LR rats showed remarkable differences following eye opening. In fact, LTD occurrence increased to about 50% in a short period of time and remained high until the adult stage. In addition, the occurrence of LTP slowly decreased to less than 20%. The effect of light-deprivation was reversible, since the exposure of DR rats to light, 5 days after eye opening, caused a sudden disappearance of LTD and a partial recover of LTP occurrence. In addition, we observed that a week of light deprivation in LR adult rats did not affect the normal adult LTP occurrence. These results provide evidence that in a critical period of development visual input plays a crucial role in shaping synaptic plasticity of the vMVN, and suggest that the visual guided shift from LTD to LTP during development may be necessary to refine and consolidate vestibular circuitry.     

Morphological and functional plasticity of olfactory ensheathing cells

In the primary olfactory pathway, olfactory ensheathing cells (OECs) extend processes to envelop bundles of olfactory axons as they course towards their termination in the olfactory bulb. The expression of growth-promoting adhesion and extracellular matrix molecules by OECs, and their spatially close association with olfactory axons are consistent with OECs being involved in promoting and guiding olfactory axon growth. Because of this, OECs have been employed as a possible tool for inducing axonal regeneration in the injured adult CNS, resulting in significant functional recovery in some animal models and promising outcomes from early clinical applications. However, fundamental aspects of OEC biology remain unclear. This brief review discusses some of the experimental data that have resulted in conflicting views with regard to the identity of OECs. We present here recent findings which support the notion of OECs as a single but malleable phenotype which demonstrate extensive morphological and functional plasticity depending on the environmental stimuli. The review includes a discussion of the normal functional role of OECs in the developing primary olfactory pathway as well as their interaction with regenerating axons and reactive astrocytes in the novel environment of the injured CNS. The use of OECs to induce repair in the injured nervous system reflects the functional plasticity of these cells. Finally, we will explore the possibility that recent microarray data could point to OECs assuming an innate immune function or playing a role in modulating neuroinflammation.     

Primary lymph node plasmocytoma of IgD-class

An extramedullary plasmocytoma in a right inguinal lymph node was observed in a 62-year-old woman. The tumor showed monoclonal proliferation of plasma cells which revealed highly positive stainings of both IgD and lambda light chain using the PAP-technique. Monoclonal IgD-lambda was also secreted in serum and urine. Clinical data, lymphography and bone biopsy showed a tumor spreading in the right inguinal, left iliacal and lumbar regions without systemic involvement of bone. In contrast to extramedullary plasmocytomas of other immunoglobulin classes the disease progressed rapidly and the patient died 8 months after the onset. The present case is the first reported IgD-plasmocytoma in lymph nodes.     

Ultrastructural analysis of the male genital system ofCephalobaena tetrapoda Heymons, 1922 (Pentastomida)

The male genital system ofCephalobaena tetrapoda comprises the unpaired testis and seminal vesicle and the paired connecting tubes, ejaculatory bulbs, vasa deferentia, and dilators. These lead into the genital atrium, which can be everted to form the copulatory organ. An ultrastructural analysis of each of these compounds is presented, including spermiogenesis, which was traced in some important stages. The diverging nomenclature of the complicated male genital system was unified and partly changed: where the vas deferens and dilator merge, the former loses its epithelial lining; the cuticular tube is called the cirrus. Anteriorly, the dilator also gives rise to a cuticular, semilunar tube. The cirrus and semilunar tube run parallel and reach the genital atrium, which can be evaginated to form the copulatory organ. Apparently, the male genital system represents an original type from which the complicated porocephalic systems may be derived.     

BK virus antibody titers and intensity of infections after renal transplantation

BACKGROUND: The mean urine BK viral load in kidney transplant recipients increases with the intensity of infection as the infection progresses from transient viruria to sustained viremia. OBJECTIVES: This study investigated whether the intensity of infection is associated with the humoral immune response. STUDY DESIGN: We measured BKV-specific IgG antibody titers in stored samples obtained serially over a 1-year period from 70 kidney transplant recipients with BKV infection and 17 control recipients without active BKV infection. RESULTS: The mean pre-transplant BKV antibody level was lower in recipients who developed viremia than the mean level in those who never developed viremia (p=0.004). Mean antibody titers in recipients who never showed evidence of active BKV infection rose slightly after transplant despite immunosuppression. The magnitude of the rise in the mean antibody titers in recipients who developed active BKV infection correlated with the intensity of infection (p<0.001). CONCLUSIONS: The mean antibody level increased in accordance with the intensity of the infection post-transplant. Pre-transplant seropositivity did not protect against sustained viremia and the antibody response was not associated with clearance of the virus.     

A novel locus for autosomal dominant, non-syndromic hearing impairment (DFNA18) maps to chromosome 3q22 immediately adjacent to the DM2 locus

Investigating a large German pedigree with non-syndromic hearing impairment of early onset and autosomal dominant mode of inheritance, linkage to known DFNA loci was excluded and in a subsequent genomic scan the phenotype was mapped to a 10-cM interval on chromosome 3q22; a maximum two-point lod score of 3.77 was obtained for the marker D3S1292. The new locus, DFNA18, is excluded from neighbouring deafness loci, DFNB15 and USH3, and it overlaps with the recently described DM2/PROMM locus. As hearing loss has been described as one feature of the PROMM phenotype, the DFNA18 gene might also be responsible for hearing loss in DM2/PROMM.     

Induction of interferon in murine bone marrow-derived macrophage cultures by 10-carboxymethyl-9-acridanone

10-Carboxymethyl-9-acridanone (CMA) induced high titers of interferon (IFN) in murine leukocyte cultures. Thymocytes, lymph node, spleen and peritoneal exudate cells responded to CMA with IFN production. Pure macrophages derived from the bone marrow were the most efficient producers of CMA-induced IFN. The yields of IFN-α β in the macrophage supernatants depended on the concentration of the inducer and titers up to 3000 IU/ml were measured after exposure to the optimal dose (500 μg/ml). CMA was found to be the first low molecular weight compound that induced in vitro titers of IFN nearly as high as obtained after exposure to Newcastle disease virus, which is one of the most potent interferon inducers.