Determination of the epitope of an inhibitory antibody to proliferating cell nuclear antigen

We identified an expansion of the CAG trinucleotide repeat in the coding region of the Machado-Joseph disease gene in 7 of 24 American families diagnosed with autosomal dominant ataxia. All affected individuals were heterozygous for an expanded allele that ranged from 67 to more than 200 CAG repeats, whereas the normal allele had 14 to 33 repeats. In contrast to the Azorean-Portuguese origins of Machado-Joseph disease, the two largest American families were of German and Dutch-African descent. Clinical, pathologic, and genetic evaluations suggest that American families with spinocerebellar ataxia type 3 differ from those with Machado-Joseph disease by their ethnic origins, predominant spinopontine atrophy, lack of dystonic features, and larger CAG repeat expansion.     

Application of polymerase chain reaction for the correlation of Salmonella serovars recovered from greyhound feces with their diet

The polymerase chain reaction was employed to correlate Salmonella serovars isolated from fecal material of greyhounds suffering from gastroenteritis with those isolated from the diet fed to the greyhounds prior to onset of diarrhea. Kennels around the Abilene, Kansas, area were contacted and supplied with materials needed to collect a portion of the diet each day. With the onset of diarrhea, the kennels were instructed to ship the fecal material and diet from the previous 10 days to the laboratory for testing. Forty-one fecal samples and corresponding diets were screened for Salmonella, Clostridium perfringens, Campylobacter jejuni, Staphylococcus aureus, Staphylococcus intermedius, and pathogenic (piliated) Escherichia coli by direct culture using standard procedures. The fecal material was also screened for coronavirus and parvovirus using electron microscopy. Thirty-five "normal" fecal samples were screened for all of the above mentioned microorganisms as a control. In addition, the fecal material was screened for E. coli verotoxins I and II and clostridial enterotoxins. A total of 61 Salmonella isolates were recovered from the 41 samples of feces and diet submitted for testing; 31 were recovered from the feces and 30 from the diet. Four Salmonella isolates were recovered from the normal fecal samples. Results obtained by PCR, plasmid profiles, antigenic analysis, and antibiogram profiles indicated that 16 of the 31 isolates recovered from the fecal material were the same strain as that recovered from the diet.     

Response of Poplar and Associated Fungal Endophytic Communities to a PAH Contamination Gradient

Microbial populations associated to poplar are well described in non-contaminated and metal-contaminated environments but more poorly in the context of polycyclic aromatic hydrocarbon (PAH) contamination. This study aimed to understand how a gradient of phenanthrene (PHE) contamination affects poplar growth and the fungal microbiome in both soil and plant endosphere (roots, stems and leaves). Plant growth and fitness parameters indicated that the growth of Populus canadensis was impaired when PHE concentration increased above 400 mg kg⁻¹. Values of alpha-diversity indicators of fungal diversity and richness were not affected by the PHE gradient. The PHE contamination had a stronger impact on the fungal community composition in the soil and root compartments compared to that of the aboveground organs. Most of the indicator species whose relative abundance was correlated with PHE contamination decreased along the gradient indicating a toxic effect of PHE on these fungal OTUs (Operational Taxonomic Units). However, the relative abundance of some OTUs such as Cadophora, Alternaria and Aspergillus, potentially linked to PHE degradation or being plant-beneficial taxa, increased along the gradient. Finally, this study allowed a deeper understanding of the dual response of plant and fungal communities in the case of a soil PAH contamination gradient leading to new perspectives on fungal assisted phytoremediation.     

Phase‐shifting differential interference contrast microscope with Savart shear prism and rotatable analyser

A novel differential interference contrast microscope (DICM) is proposed in this research. It is constituted by inserting a Savart shear prism between the objective and sample of a polarising microscope having a rotatable analyser as the phase‐shifter, and it is with the ability to enhance image contrast using the principle of shearing interferometry. This letter is to introduce the configuration, interpret the interference patterns and present the experimental setup of the DICM. In addition, this letter is to display the experimental results from the uses of the setup; the results demonstrate the validity and ability of the DICM.     

Oestradiol up-regulates oestrogen receptor, cyclophilin, and glyceraldehyde phosphate dehydrogenase mRNA concentrations in endometrium, but down-regulates them in liver

Oestradiol regulates reproductive physiology and cardiovascular health in women. In the endometrium of ovariectomized ewes, previous work demonstrated that a single dose of oestradiol (50 microg) up-regulates oestrogen receptor-alpha (ER) and progesterone receptor (PR) gene expression within 24 h. Here we compared responses to different doses of oestradiol and different dosing regimens in two diverse tissues: endometrium and liver. ER, c-fos, cyclophilin and glyceraldehyde phosphate dehydrogenase (GAPDH) mRNA concentrations were analyzed on replicate RNA slot blots in both tissues, while PR and apolipoprotein AI (apo AI) mRNA concentrations were only analyzed in endometrium or liver, respectively. Along with ER mRNA, oestradiol strongly up-regulated GAPDH and cyclophilin mRNA concentrations in endometrium. In liver, however, oestradiol down-regulated them, along with apo AI mRNA. Responses to different doses and dose regimens, including repeated 50 microg doses, were similar to those evoked by a single 50 microg dose of oestradiol. Thus, oestradiol appears to have all-or-none effects which include up-regulation of ER, cyclophilin and GAPDH gene expression in endometrium and down-regulation of ER, apo AI, cyclophilin and GAPDH gene expression in liver. These results illustrate the sharp contrast between two mammalian tissues in their responses to physiological levels of oestradiol.     

Cholinergic blockade and the mesenteric artery response to head-up tilt-induced central hypovolaemia

The methylation of phosphatidylethanolamine is an auxiliary pathway for phosphatidylcholine biosynthesis in liver. Two forms of the enzyme, phosphatidylethanolamine N-methyltransferase, which catalyses this reaction, are located on the endoplasmic reticulum and mitochondria-associated membranes. Both forms are encoded by a single murine gene, Pempt, located on chromosome 11. The expression of the gene begins at birth. An inverse relationship exists between the rate of liver growth and the expression of phosphatidylethanolamine N-methyltransferase. However, disruption of the Pempt gene does not alter liver growth in mice or cause any other obvious phenotype.     

Glycobiology and proteomics: is mass spectrometry the Holy Grail?

One characteristic of glycoproteins is that they are separated by two-dimensional electrophoresis (2-D PAGE) into typical 'trains' of protein spots which separate on the basis of different isoelectric point (pI) and/or molecular mass. The pattern of these trains often varies in development and disease. While the isoforms differ both in the number of sites of glycosylation and the types of carbohydrate attached to the protein, classical methods of glycan analysis are insensitive at the levels typically separated by 2-D PAGE. Developments in mass spectrometry technologies have enabled the characterization of most of the oligosaccharide attributes to be determined on picomole amounts of protein. These techniques are beginning to allow the glycoform heterogeneity on 2-D separated glycoproteins to be analyzed.