Infection of endothelial cells with Anaplasma marginale and A. phagocytophilum

Anaplasma marginale and A. phagocytophilum are obligate intracellular, tick-borne pathogens that target erythrocytes and neutrophil granulocytes, respectively. Because ticks do not directly tap blood vessels, an intermediate tissue may mediate infection of blood cells. We considered that vascular endothelium interacts with circulating blood cells in vivo, and could be involved in pathogenesis and dissemination of the organisms. We used light and electron microscopy and immune labeling to show that A. phagocytophilum invaded rhesus (RF/6A), human (HMEC-1, MVEC), as well as bovine (BCE C/D-1b) endothelial cell lines, whereas A. marginale infected rhesus and bovine endothelial cells. A. marginale formed large intracellular inclusions that appeared smooth and solid at first, and subsequently coalesced into discrete granules. A. phagocytophilum formed numerous smaller inclusions in each cell. Within 1-3 weeks, the monolayers were destroyed, and lysed cultures were diluted onto fresh monolayers. Electron microscopy demonstrated uneven distribution of A. marginale inside large inclusions, with reticulated forms grouped more tightly than denser cells, whereas in A. phagocytophilum individual organisms appeared more evenly spaced. Specific polyclonal and monoclonal antibodies both labeled A. marginale and A. phagocytophilum in endothelial cells, and oligonucleotide primers complimentary to either A. marginale or A. phagocytophilum amplified their expected target from these cultures. In conclusion, we demonstrate that relevant microvascular endothelium is susceptible to anaplasmas in vitro and may present a link that could explain development of the immune response and persistent infection.     

Surveillance and control of rabies in La Reunion,Mayotte, and Madagascar

Mayotte and La Reunion islands are currently free of animal rabies and surveillance is performed by the French Human and Veterinary Public Health Services. However, dog rabies is still enzootic in Madagascar with 4 to 10 confirmed human cases each year. The number of antirabies medical centres in Madagascar is still scarce to provide easy access to the local population for post-exposure rabies prophylaxis. Furthermore, stray dog populations are considerable and attempts to control rabies by mass campaigns of dog vaccination have not received sufficient attention from the national health authorities. To address these challenges, an expanded program to control rabies needs to be initiated by the Malagasy authorities.     

A practical approach to diagnosis of swine diseases

Blood samples from the vena cava or jugular vein should be chilled but not frozen, and serum chilled or frozen. Tissue specimens for bacteriologic or virologic examination should be chilled in individual plastic bags and frozen if not submitted immediately. Live pigs should be submitted for TGE studies. Tissue specimens for histologic examination should be placed in formalin and not frozen. Aborted fetuses and fetal membranes are more useful if fresh. In baby pigs, the rectal temperature and WBC counts are not reliable indicators of health; the liver may be yellow and the kidneys petechiated in normal baby pigs.     

Drosophila melanogaster treated with LSD: absence of mutation and chromosome breakage

Injection of lysergic acid diethylamide in Drosophila melanogaster males induced no mutations or chromosome breaks in premeiotic, meiotic, or postmeiotic sperm. Tests included those for sex-linked lethals, sex-linked visibles, a specific visible (dumpy), and translocations. Some implications of these experiments are discussed.     

Oesophageal carcinoma in the dog

Two cases of undiflerentiated carcinoma of the canine oesophagus are described. Both cases presented with symptoms of dysphagia and vomiting and both were initially diagnosed by oesophagoscopy. Barium swallow radiographs in both cases revealed definite filling defects. Because of its size, surgical excision was attempted in Case 1, but the dog died soon after surgery. In Case 2, the tumour was inoperable because of its extensive involvement of the entire anterior portion of the thoracic oesophagus and diffuse metastasis to the lungs. Résumé. On décrit deux cas de carcinome non-différencié de l'?sophage canin. Ces deux cas, présentant des symptómes de dysphagie et de vomissements, ont été tous deux initialement diagnostiqués au moyen d'une ?sophagoscopie. Dans les deux cas, des radiographies du baryum avalé ont révélé des images lacunaires bien définies. A cause de son volume, on a tenté une excision chirurgicale dans le premier cas mais le chien est mort peu après l'intervention chirurgicale. Dans le second cas, la tumeur était inopérable à cause de l'implication extensive de l'entière portion antérieure de l'?sophage thoracique et à cause d'une métastase diffusée aux poumons. Zusammenfassung. Zwei Fälle von nichtdifferenziertem Karzinom der Hundespeiseröhre sind beschrieben. Beide Fälle zeigten Symptome von Dysphagia und Erbrechen und beide Diagnosen waren anfangs durch Speiseröhrenbetrachtung festgestellt. Barium-Schluck Röntgenaufnahmen zeigten deutliche Füllungsdefekte. Wegen seiner Grösse versuchte man in dem einen Fall chirurgische Excision, doch der Hund starb bald nach der Operation. In dem zweiten Fall war der Tumor nicht operierbar, wegen seiner ausgedehnten Verwicklung im gesamten vorderen Teil der thorakal Oesophagus und verbreiteter Metastase in der Lunge.     

Intron existence predated the divergence of eukaryotes and prokaryotes

Nucleotide sequences for the nuclear genes encoding chloroplast (GapA and GapB) and cytosolic (GapC) glyceraldehyde-3-phosphate dehydrogenases (GAPDHs) from Arabidopsis thaliana were determined. Comparison of nucleotide sequences indicates that the divergence of chloroplast and cytosolic GAPDH genes preceded the divergence of prokaryotes and eukaryotes. In addition, some intron-exon junctions are conserved among GapB, GapC, and chicken GAPDH genes. These results provide evidence at the molecular level to support the idea that introns existed before the divergence of prokaryotes and eukaryotes.     

A phylogenetic microarray targeting 16S rRNA genes from the bacterial division Acidobacteria reveals a lineage-specific distribution in a soil clay fraction

We designed an oligonucleotide microarray using probe sequences based upon a phylogenetic analysis of 16S rRNA genes recovered from members of the bacterial division Acidobacteria. A total of 42,194 oligonucleotide probes targeting members of the Acidobacteria division at multiple phylogenetic levels were included on a high-density microarray. Positive control hybridizations revealed a linear relationship between hybridization signal and template concentration, and a substantial decrease in non-specific hybridization was achieved through the addition of 2.5 M betaine to the hybridization buffer. A mean hybridization signal value was calculated for each Acidobacteria lineage, with the resultant lineage-specific hybridization data revealing strong predictive value for the positive control hybridizations. The Acidobacteria phylochip was then used to evaluate Acidobacteria rRNA genes from a Wisconsin soil and within a soil clay fraction. The Acidobacteria hybridization profile revealed the predominance of Acidobacteria subdivisions four and six, and also suggested a decrease in the abundance of subdivision six relative to subdivision four in the soil clay fraction. The change in relative abundance of these subdivisions in a soil clay fraction was supported by data from quantitative PCR. These results support the utility of a phylogenetic microarray in revealing changes in microbial population-level distributions in a complex soil microbial assemblage.