Genetic mapping ofPim-1 putative oncogene to mouse chromosome 17

Pim-1 is a putative oncogene activated in T-cell lymphomas induced by Moloney and AKR mink cell focus forming (MCF) viruses. We have determined the chromosomal localization of the Pim-1gene in mice by Southern blot analysis of DNAs obtained from a panel of mouse-Chinese hamster somatic cell hybrids. The Pim-1gene was localized on chromosome 17, a chromosome frequently aberrant in T-cell lymphomas. Two chromosomal regions, containing sequences homologous to regions within the Pim-1locus, were localized on chromosome 6 and 16.     

Multiblock poly(ether-ester-amide)s based on polyamide-6 and poly(ethylene glycol), 2 Effect of composition and soft-segment length on the structure of poly(ether-ester-amide)s as revealed by X-ray scattering

Isotropic unannealed and annealed melt-pressed and quenched samples of segmented multiblock poly(ether-ester-amide)s based on polyamide-6 and poly(ethylene glycol)s (PEGs) of molecular weights 400 and 1000 with various hard/soft segment weight ratios were investigated. The effect of composition, segment length and annealing temperature on the crystal structure was studied by differential scanning calorimetry, wide-angle and small-angle X-ray scattering. In addition to the γ-phase, one of the unannealed samples having relatively long hard and soft segments exhibits a high amount of α-phase. This is assumed to be due to the high flexibility of the PEG segments, linking the polyamide blocks thus enhancing their mobility. The lack of hydrogen bonds between the PEG segments facilitates crystallization of the polyamide segments in the more perfect α-modification, which is the most pronounced in the above mentioned sample. Part of the α-phase transforms into the α-phase upon annealing in all copolymer samples studied, similarly to polyamide-6.     

Effect of a new synthetic serum replacement on insulin and somatostatin secretion from isolated rat pancreatic islets in long-term culture

Summary Serum contains insulin degrading components. We have evaluated the insulin and somatostatin secretion from isolated rat pancreatic islets during a 2-wk culture period using three different serum-containing media, and one serum-free medium with a synthetic serum replacement. Islets incubated in serum-free medium elicited significantly higher daily insulin and somatostatin secretions than islets incubated in the serum-containing media. After a 2-wk culture period, islets from the serum-free medium secreted significantly more insulin and somatostatin than islets cultured in other media when stimulated with 25 mmol/liter glucose together with 15 mmol/liter theophylline. We conclude that the serum-free medium is superior for long-term culture of rat pancreatic islets.     

Züchtung des Variolavirus in der infantilen Maus

Zusammenfassung Das Variolavirus konnte aus menschlichem Pustel- und Krustenmaterial intraperitoneal in infantilen Mäusen angezüchtet und in fortlaufenden Passagen weitergeführt werden. Es blieb innerhalb von 20 Passagen in bezug auf seine biologischen Eigenschaften im Hühnerembryo stabil. Eintägige Mäuse waren empfänglicher als dreitägige Tiere. Innerhalb verschiedener Mäusefamilien bestand eine unterschiedliche Resistenz gegenüber der Variolainfektion. Bei resistenteren Tieren vermehrte sich das Virus, ohne klinische Erscheinungen zu verursachen.Ein besonders bevorzugtes Organ für die Vermehrung des Variolavirus war die Lunge.Bei infizierten, klinisch aber gesunden Mäusen ließ sich aus den Lungen der Tiere in einem Zeitraum von 45 Tagen p. i. infektiöses Variolavirus züchten.     

Rapid,non-genomic actions of progesterone and estradiol on steady-state calcium and resting calcium influx in lens epithelial cells

The effects of steroids on the steady-state intracellular [Ca(2+)] ([Ca(2+)](i)) and resting Ca(2+) influx in Fura-2-loaded bovine lens epithelial cells were examined to identify potential rapid, non-genomic actions. When administered in the presence of 1-2 mM extracellular Ca(2+) ([Ca(2+)](o)), 100 micro M progesterone produced large (up to 12-fold) and transient (5 min) increases in [Ca(2+)](i). These effects were abolished in EGTA-containing solutions, and were associated with large increases in the rate at which extracellularly administered Mn(2+) quenched the intracellular Fura signal. Lower concentrations of progesterone (10-100 micro M) produced smaller increases in [Ca(2+)](i) that were concentration dependent, and 17beta-estradiol induced large, rapid and brief increases in [Ca(2+)](i) at 100 nM and smaller oscillations in [Ca(2+)](i) at 10 nM. In cells pretreated with thapsigargin, 100 micro M progesterone produced slower increases in [Ca(2+)](i) that were maintained for several minutes. These results demonstrate rapid non-genomic actions of progesterone and estradiol on resting Ca(2+) influx and [Ca(2+)](i) that may involve specific interactions with a recently discovered steroid-binding protein in the plasma membrane of lens epithelial cells.     

Connexin 26 mutations in cases of sensorineural deafness in eastern Austria

Mutations in the connexin 26 (Cx26) gene (GJB2) are associated with autosomal nonsyndromic sensorineural hearing loss. This study describes mutations in the Cx26 gene in cases of familial and sporadic hearing loss (HL) by gene sequencing and identifies the allelic frequency of the most common mutation leading to HL (35delG) in the population of eastern Austria. For this purpose we have developed and applied a molecular beacon based real-time mutation detection assay. Mutation frequencies in the Cx26 gene of individuals from affected families (14 out of 46) and sporadic cases (11 out of 40) were 30.4% and 27.5%, respectively. In addition to known disease related alterations, a novel mutation 262 G-->T (A88S) was also identified. 35delG accounted for almost 77% of all Cx26 mutations detected and displayed an allelic frequency in the normal hearing population of 1.7% (2 out of 120). The high prevalence of the 35delG mutation in eastern Austria would therefore allow screening of individuals and family members with Cx26 dependent deafness by a highly specific and semi-automated method.     

What evidence is there for the existence of individual genes with antagonistic pleiotropic effects?

Classical evolutionary theory predicts the existence of genes with antagonistic effects on longevity and various components of early-life fitness. Quantitative genetic studies have provided convincing evidence that such genes exist. However, antagonistic pleiotropic effects have rarely been attributed to individual loci. We examine several classes of longevity-assurance genes: those involved in regulation of the gonad; the insulin-like growth factor pathway; free-radical scavenging; heat shock proteins and apoptosis. We find initial evidence that antagonistic pleiotropic effects are pervasive in each of these classes of genes and in various model systems--although most studies lack explicit studies of fitness components. This is particularly true of human studies. Very little is known about the early-life fitness effects of longevity loci. Given the possible medical importance of such effects we urge their future study.     

Characterization of nutritionally variant streptococci by biochemical tests and penicillin-binding proteins.

A comparative study of 60 strains of nutritionally variant streptococci (NVS) with 34 strains of Streptococcus mitis and 37 strains of Streptococcus sanguis II showed the presence of a red chromophore which was absent in the other streptococcal species. By using the conventional microbiological tests, only small differences were found between the NVS and the two other related species. In contrast a clear-cut delineation was found by the API 20 Strep system of identification. All NVS contained pyrrolidonylarylamidase, an enzyme which was absent in S. mitis and S. sanguis II strains, and lacked the alkaline phosphatase enzyme which was present in 56% of S. mitis strains and 62% of S. sanguis II strains. According to the additional enzymatic and biochemical tests of the API 20 Strep system, there were three biotypes among NVS. The major biotype included 33 of 60 strains which were characterized by the presence of both alpha- and beta-galactosidases and the capacity to hydrolyze trehalose. This biotype also showed a specific pattern of penicillin-binding proteins. These results show that NVS are recognized as a separate variety distinct from S. mitis and S. sanguis II species, despite some common biochemical properties. Moreover, the delineation of 33 strains with a specific biotype and a specific penicillin-binding protein pattern strongly suggests that a large part of NVS strains belong to an individual species.     

Mental and physical effort affect vigilance differently.

Both physical and mental effort are thought to affect vigilance. Mental effort is known for its vigilance declining effects, but the effects of physical effort are less clear. This study investigated whether these two forms of effort affect the EEG and subjective alertness differently. Participants performed a physical task and were subsequently presented with a mental task, or vice versa. Mental effort decreased subjective alertness and increased theta power in the EEG. Both results suggest a vigilance decline. Physical effort, however, increased subjective alertness and alpha and beta1 power in the EEG. These findings point towards an increase in vigilance. Beta2 power was reduced after physical effort, which may reflect a decrease in active cognitive processing. No transfer effects were found between the effort conditions, suggesting that the effects of mental and physical effort are distinct. It is concluded that mental effort decreases vigilance, whereas physical effort increases vigilance without improving subsequent task performance.     

Detection of Leishmania infantum kinetoplast DNA in laryngeal tissue from an immunocompetent patient

Mucosal leishmaniasis of the upper respiratory tract is usually associated with the visceral form or is found in immunosuppressed individuals. This report presents a case of isolated mucosal leishmaniasis in an immunocompetent patient, whose diagnosis mainly rested on histology and positive polymerase chain reaction result for Leishmania donovani in the laryngeal tissue. A 59-year-old man, who never lived outside Italy, showed a subglottic mucosal polypoid-like lesion. The typical morphological picture and positive polymerase chain reaction result for L donovani by DNA extracted from laryngeal biopsy specimens allowed the diagnosis of mucosal leishmaniasis. Specific amphotericin B therapy was started, resulting in clinical and endoscopic improvement. Increased knowledge about the histological and molecular tissue analysis of Leishmania enhances the diagnostic testing for mucosal leishmaniasis, as primary mucosal leishmaniasis may occur in both immunosuppresed and immunocompetent patients who travel to or reside in areas endemic for Leishmania.