Spinal cord sarcoidosis

We present a case of spinal cord sarcoidosis which resembled a disseminated intramedullary tumour. The case is unusual because the spinal cord is only rarely affected by sarcoidosis and the patient developed a neurological deficit as the first manifestation of the disease. This condition thus has to be considered in the differential diagnosis of primary intramedullary tumours, or metastatic disease with involvement of the spinal cord.     

Bilateral facial palsy: Epstein–Barr virus, not Lyme disease

Bilateral facial palsy is frequently linked with lyme disease. We report a patient with bilateral facial palsy due to Epstein-Barr virus infection but with Borrelia burgdorferi IgM in serum caused by polyclonal B-lymphocyte stimulation.     

Abnormal astrocyte differentiation and defective cellular interactions in wobbler mouse spinal cord

Summary The wobbler mutation is inherited as an autosomal recessive trait and displays a muscular atrophy associated with motoneuron degeneration in early postnatal development. It has been shown that the level of glial fibrillary acidic protein (GFAP) is greatly increased in the spinal cord of wobbler mice. We performed immunocytochemical analyses combined with confocal microscopy to study the developmental distribution of GFAP-positive astrocytes in the spinal cord of wobbler mice during the course of the disease, and in primary cultures of adult wobbler spinal cord astrocytes. Many changes in the number and distribution of astrocytes were observed in the wobbler mice from 1–10 months post-partum. Strongly GFAP-positive astrocytes are present in small number in the anterior horn by 1 month. They increase in number and are observed in the entire spinal cord grey and white matters by 2–10 months. These reactive astrocytes have thick, short, extensively branched processes which contrast with the long, unbranched processes observed in control mice. The wobbler astrocyte processes are oriented perpendicular to the surface of the spinal cord, which contrasts with the normal parallel, concentric orientation. No expansion of astrocyte processes exit from the white matter towards the grey matter. Moreover, the surface of the wobbler spinal cord beneath the meninges displays a dramatic decrease of interdigitating processes, end feet and flattened cell bodies of astrocytes that form a disorganized layer.In vitro, mutant astrocytes have morphological characteristics similar to thosein vivo and, in particular, develop short, thick, branched processes. These mutant astrocytes in cultures do not contact one another, whereas normal mature cultures show an increased incidence of cell-cell contacts between long processes. The increase of astrocyte reactivity associated with these modifications in astrocytic process arrangement may reflect an important primary event in the course of the wobbler disease rather than a non-specific response to motoneuronal death.     

Tissue inhibitor of metalloproteinase 1 activates normal human granulocytes, protects them from apoptosis, and blocks their transmigration during inflammation

Urinary levels of tissue inhibitor of metalloproteinase 1 (TIMP-1) higher than those of matrix metalloproteinase 9 (MMP-9) during acute pyelonephritis have previously been associated with a higher degree of acute inflammation and of postinfective renal scarring. The aim of the present study was to evaluate possible mechanisms by which TIMP-1 could affect the scarring process already during the acute phase of inflammation. The growth of Escherichia coli, bactericidal activity of fresh human blood, and respiratory burst, spontaneous apoptosis, and trans-basement membrane migration of normal human granulocytes were studied in vitro in the presence of different concentrations of recombinant human TIMP-1. To imitate the "normal" environment during inflammation in the kidney, granulocytes were also incubated with a conditioned medium from E. coli-stimulated renal epithelial cells. In order to compare our data with the in vivo situation, blood and urinary leukocyte levels were analyzed for 40 children with acute pyelonephritis, together with urinary MMP-9 and TIMP-1 levels. TIMP-1 at a concentration of 500 ng/ml increased the bactericidal activity of blood, increased the respiratory burst of granulocytes, decreased phosphatidylserine exposure and caspase 3 activity, which are features of spontaneous apoptosis, and inhibited granulocyte transmigration. Moreover, in the patients with pyelonephritis, MMP-9/TIMP-1 ratios in urine correlated with the degree of leukocyte transmigration. Thus, our data suggest that TIMP-1 specifically blocks the transmigration of granulocytes into urine. Entrapped and activated granulocytes, protected from apoptosis, might excessively destroy renal parenchyma and thus contribute to the pathogenesis of renal scarring following acute pyelonephritis.     

Frequency of rpoB mutations inside and outside the cluster I region in rifampin-resistant clinical Mycobacterium tuberculosis isolates

The prevalence of recently described mutation V176F, located in the beginning of the rpoB gene and associated with rifampin resistance and the wild-type cluster I sequence, was determined by analyzing the distribution of rpoB mutations among 80 rifampin (RIF)-resistant Mycobacterium tuberculosis strains isolated in Germany during 1997. The most frequent rpoB mutations were changes in codon 456 (52 isolates, 65%), followed by changes in codon 441 (13 isolates, 16%) and codon 451 (11 isolates, 14%). The V176F mutation was detected in one isolate of the study population and in 5 of 18 RIF-resistant strains with no cluster I mutation from six previously published studies. In three isolates, a mixture of resistant and susceptible subpopulations (heteroresistance) prohibited the detection of rpoB mutations in the initial analysis; however, in these isolates, cluster I mutations could be verified after a passage on RIF-containing medium. IS6110 DNA fingerprinting of 76 strains revealed eight clusters comprising 27 strains with identical restriction fragment length polymorphism patterns that mainly also show identical rpoB mutations and identical or similar drug resistance patterns. In conclusion, our results indicate that the V176F mutation should be included in molecular tests for prediction of RIF resistance in M. tuberculosis. We further demonstrated that heteroresistance caused by a mixture of mycobacterial subpopulations with different susceptibilities to RIF may influence the sensitivity of molecular tests for detection of resistance.     

A 1463 gene cattle-human comparative map with anchor points defined by human genome sequence coordinates

A second-generation 5000 rad radiation hybrid (RH) map of the cattle genome was constructed primarily using cattle ESTs that were targeted to gaps in the existing cattle-human comparative map, as well as to sparsely populated map intervals. A total of 870 targeted markers were added, bringing the number of markers mapped on the RH(5000) panel to 1913. Of these, 1463 have significant BLASTN hits (E < e(-5)) against the human genome sequence. A cattle-human comparative map was created using human genome sequence coordinates of the paired orthologs. One-hundred and ninety-five conserved segments (defined by two or more genes) were identified between the cattle and human genomes, of which 31 are newly discovered and 34 were extended singletons on the first-generation map. The new map represents an improvement of 20% genome-wide comparative coverage compared with the first-generation map. Analysis of gene content within human genome regions where there are gaps in the comparative map revealed gaps with both significantly greater and significantly lower gene content. The new, more detailed cattle-human comparative map provides an improved resource for the analysis of mammalian chromosome evolution, the identification of candidate genes for economically important traits, and for proper alignment of sequence contigs on cattle chromosomes.     

Granulocyte Stimulating Factor in Patients on Peritoneal Dialysis and LPS Stimulated Peripheral Blood Mononuclear Cells

Dialysate and serum levels of granulocyte-colony stimulating factor (G-CSF), granulocyte macrophage colony stimulating factor (GM-CSF) and leukemia inhibitory factor (LIF) were analyzed in patients with continuous ambulatory peritoneal dialysis (CAPD). Samples from the peritoneal effluent and from serum were obtained during the first months of dialysis and during peritonitis from the first three dialysate bags drained on the day of admittance and from nightbags on days three and ten. Serum samples were drawn on days one and ten. On the first day of infection G-CSF was detected in twelve out of fifteen samples in the dialysate and reached its peak median level, 443 pg/ml, in the first drained bag and thereafter decreased significantly. Also in serum a peak, 190 pg/ml, was observed on the first day. LIF was found in six of ten analyzed dialysate samples, with a peak median level of 77 pg/ml on day one, while only four of ten patients had detectable GM-CSF. Peripheral blood mononuclear cells from non-infected CAPD patients were stimulated with lipopolysacharide and G-CSF levels in the supernatants increased significantly (P < 0.05) after 6 h stimulation. We conclude that G-CSF is produced locally in the dialysate during the acute stage of peritonitis and to a lesser extent also systemically. These findings are in line with G-CSF production after LPS stimulation of peripheral blood mononuclear cells.