Multiple copies of Shope virus DNA are present in cells of benign and malignant non-virus-producing neoplasms.

In an initial efforts to characterize the virological basis of neoplasia in the Shope papilloma-carcinoma system, the extent to which the viral genome is present in non-virus-producing benign and malignant tumors in domestic rabbits was established. Employing nick-translated radioactive viral DNA purified from productively infected papillomas on cotton tail rabbits as a probe, it was found that (i) papillomas, primary carcinomas, and metastatic carcinomas contain 10 to about 100 copies of the viral genome per diploid cell equivalent of DNA and (ii) viral DNA is present in detectable amounts in essentially all neoplastic cells. These results are consistent with the suggestion that continued presence of the viral genome is necessary for induction and maintenance of malignant as well as benign neoplasms.     

Development of synaptic responses and plasticity at the SC-CA1 and MF-CA3 synapses in rat hippocampus

1. The development of synaptic transmission and indicators of short- and long-term plasticity was studied by recording from areas CA1 and CA3 upon activation of monosy- naptic excitatory inputs in rat hippocampal brain slices obtained from Wistar rats of different ages.2. Although population field excitatory postsynaptic potentials (fEPSPS) are small in animals at postnatal day 10 (P10), both areas already exhibited short-term [posttetanic potentiation (PTP) and paired pulse potentiation (PPF)] and long-term [long-term potentiation (LTP)] plastic responses.3. The amplitudes of the fEPSP and LTP increased with age in both regions, but peaked at P30 in CA3 while they were still increasing at the oldest age studied (P60) in CA1. In CA3, but not CA1, LTP at P60 was less than at P30.4. PTP did not show clear alterations with age in either region. PPF decreased with age in CA1 but not CA3.     

The functional domains of coagulation factor VIII:C

A lack of factor VIII:C, manifested as a bleeding disorder due to the absence of clot formation, is known as hemophilia A, an X chromosome-linked inherited disease afflicting 1-2 males/10,000. To determine the minimum functional domain(s) essential for factor VIII:C activity, we have expressed the amino-terminal (92-kDa) and carboxyl-terminal (80-kDa) proteolytic cleavage products as individual, secreted polypeptides in monkey cells without the 909-residue central region. We have found that neither terminal domain alone is able to promote coagulation in factor VIII:C-deficient plasma. However, when the 92- and 80-kDa peptides are co-expressed, clotting activity is readily detected. Thus, these two chains alone constitute an active or activatable complex. The central domain is required neither for activity nor for the assembly of an active complex from two chains expressed in trans. These results suggest that a truncated derivative of factor VIII:C may be useful in coagulation therapy.     

Validation of a brief telephone battery for neurocognitive assessment of patients with pulmonary arterial hypertension

Background

The effects of pulmonary arterial hypertension on brain function are not understood, despite patients'' frequent complaints of cognitive difficulties. Using clinical instruments normally administered during standard in-person assessment of neurocognitive function in adults, we assembled a battery of tests designed for administration over the telephone. The purpose was to improve patient participation, facilitate repeated test administration, and reduce the cost of research on the neuropsychological consequences of acute and chronic cardiorespiratory diseases. We undertook this study to validate telephone administration of the tests.

Methods

23 adults with pulmonary arterial hypertension underwent neurocognitive assessment using both standard in-person and telephone test administration, and the results of the two methods compared using interclass correlations.

Results

For most of the tests in the battery, scores from the telephone assessment correlated strongly with those obtained by in-person administration of the same tests. Interclass correlations between 0.5 and 0.8 were observed for tests that assessed attention, memory, concentration/working memory, reasoning, and language/crystallized intelligence (p ≤ 0.05 for each). Interclass correlations for the Hayling Sentence Completion test of executive function approached significance (p = 0.09). All telephone tests were completed within one hour.

Conclusion

Administration of this neurocognitive test battery by telephone should facilitate assessment of neuropsychological deficits among patients with pulmonary arterial hypertension living across broad geographical areas, and may be useful for monitoring changes in neurocognitive function in response to PAH-specific therapy or disease progression.     

Characterization of a Paenibacillus cell-associated xylanase with high activity on aryl-xylosides: a new subclass of family 10 xylanases

The sequence of gene xynB encoding xylanase B from Paenibacillus sp. BP-23 was determined. It revealed an open reading frame of 999 nucleotides encoding a protein of 38,561 Da. The deduced amino acid sequence of xylanase B shows that the N-terminal region of the enzyme lacks the features of a signal peptide. When the xylan-degrading system of Paenibacillus sp. BP-23 was analysed in zymograms, it revealed that xylanase B was not secreted to the extracellular medium but instead remained cell-associated, even in late stationary-phase cultures. When xynB was expressed in a Bacillus subtilis secreting host, it also remained associated with the cells. Sequence homology analysis showed that xylanase B from Paenibacillus sp. BP-23 belongs to family 10 glycosyl hydrolases, exhibiting a distinctive high homology to six xylanases of this family. The homologous enzymes were also found to be devoid of a signal peptide and seem to constitute, together with xylanase B, a separate group of enzymes. They all have two conserved amino acid regions not found in the other family 10 xylanases, and cluster in a separate group after dendrogram analysis. We propose that these enzymes constitute a new subclass of family 10 xylanases, that are cell-associated, and that hydrolyse the xylooligosaccharides resulting from extracellular xylan hydrolysis. Xylanase B shows similar specific activity on aryl-xylosides and xylans. This can be correlated to some, not yet identified, trait of catalytic activity of the enzyme on plant xylan.     

<Emphasis Type="Italic">Saturnispora serradocipensis</Emphasis> sp. nov. and <Emphasis Type="Italic">Saturnispora gosingensis</Emphasis> sp. nov., two ascomycetous yeasts from ephemeral habitats

Two novel ascomycetous yeast species, Saturnispora serradocipensis and Saturnispora gosingensis, were isolated from leaf detritus in a tropical stream of Southeastern Brazil and a mushroom collected in Taiwan, respectively. Analysis of the D1/D2 domains of the large-subunit of the rRNA gene of these strains showed that these species are related to Saturnispora hagleri, their closest relative. Saturnispora serradocipensis and S. gosingensis differed from S. hagleri, respectively, by seven nucleotide substitutions and two indels and three nucleotide substitutions and three indels in D1/D2 rRNA sequences. The two new species differ from each another by four nucleotide substitutions and one indel in D1/D2 rRNA sequences. However, the ITS sequences of S. serradocipensis, S. gosingensis and S. hagleri were quite divergent, showing that they are genetically separate species. The type strain of S. serradocipensis is UFMG-DC-198^T (=CBS 11756^T = NRRL Y-48717^T), and of S. gosingensis GA4M05^T is (CBS 11755^T = NRRL Y-48718^T).     

Germline and Somatic Mutations of Genes Involved in Tumor Formation in Sporadic Renal Angiomyolipoma

Russian Journal of Genetics - Angiomyolipoma (AML) is one of the most frequent and, at the same time, AML molecular genetics is one of the least studied among benign tumors. We performed deep...