Simultaneous real-time PCR detection of <Emphasis Type="Italic">Bacillus anthracis</Emphasis>, <Emphasis Type="Italic">Francisella tularensis</Emphasis> and <Emphasis Type="Italic">Yersinia pestis</Emphasis>

This report describes the development of in-house real-time PCR assays using minor groove binding probes for simultaneous detection of the Bacillus anthracis pag and cap genes, the Francisella tularensis 23 KDa gene, as well as the Yersinia pestis pla gene. The sensitivities of these assays were at least 1 fg, except for the assay targeting the Bacillus anthracis cap gene, which showed a sensitivity of 10 fg when total DNA was used as a template in a serial dilution. The clinical value of the Bacillus anthracis- and Francisella tularensis-specific assays was demonstrated by successful amplification of DNA from cases of cow anthrax and hare tularemia, respectively. No cross-reactivity between these species-specific assays or with 39 other bacterial species was noted. These assays may provide a rapid tool for the simultaneous detection and identification of the three category A bacterial species listed as biological threats by the Centers for Disease Control and Prevention.     

In vivo encystation of <Emphasis Type="Italic">Blastocystis hominis</Emphasis>

Blastocystis from infected stools of a person who showed chronic symptoms of abdominal discomfort and diarrhea were examined over a 6-month period, using transmission electron microscopy, for the ultrastructural changes from vacuolar to cystic stage. The study confirms the irregular shedding phenomenon of the organism previously reported, and for the first time, records sequential changes in encystation in stools collected over a time period. The study also confirms the existence of a precystic stage which has an immature cell wall consisting of a layer of a homogenous electron-dense mass surrounding the cell which acts as a intermediatory stage between the vacuolar and cystic stage.     

<Emphasis Type="Italic">Trichomonas vaginalis</Emphasis> harboring <Emphasis Type="Italic">Mycoplasma hominis</Emphasis> increases cytopathogenicity in vitro

The parasite Trichomonas vaginalis causes one of the most common non-viral sexually transmitted infections in humans. Mycoplasmas are frequently found with trichomonads but the consequences of this association are not yet known. In the present study, the effects of T. vaginalis harboring M. hominis on human vaginal epithelial cells and on MDCK cells are described. The results were analyzed by light, scanning and transmission electron microscopy, as well as using cell viability assays. There was an increase in the cytopathic effects on the epithelial cells infected with T. vaginalis associated with M. hominis compared to T. vaginalis alone. The epithelial cells exhibited an increase in the intercellular spaces, a lesser viability, and increased destruction provoked by the infected T. vaginalis. In addition, the trichomonads presented a higher amoeboid transformation rate and an intense phagocytic activity, characteristics of higher virulence behavior.     

SCC<Emphasis Type="Italic">mec</Emphasis> and <Emphasis Type="Italic">spa</Emphasis> types of methicillin-resistant <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> strains in Israel. Detection of SCC<Emphasis Type="Italic">mec</Emphasis> type V

Molecular characterization of methicillin-resistant Staphylococcus aureus isolates from three hospitals in Israel was the aim of the study presented here. We identified 11 distinct genetic clones by pulsed-field gel electrophoresis. Molecular typing identified four different SCCmec types—I, II, IV, and V−and nine spa types. Spa type t002 was the most common. An erratum to this article can be found at     

<Emphasis Type="Italic">In situ</Emphasis> and <Emphasis Type="Italic">ex vivo</Emphasis> evaluation of a wireless magnetoelastic biliary stent monitoring system

This paper presents the in situ and ex vivo evaluation of a system that wirelessly monitors the accumulation of intimal tissue and sludge in a biliary stent. The sensing element, located within the stent, is a magnetoelastic resonator that is queried by a wireless radio frequency signal. The in situ testing uses a commercially-available self-expanding biliary stent enhanced with a 1 mm × 25 mm magnetoelastic ribbon sensor (formed from Metglas™ 2605SA1). The stent has a conformal magnetic layer (consisting of strontium ferrite particles suspended in polydimethylsiloxane) that biases the sensor. The external interrogation module is able to acquire a signal from the sensor from a distance of at least 5 cm while the sensor is implanted in a porcine carcass and loaded with biological fluids. The ex vivo testing uses bile harvested from the porcine carcass. The response of a 1 mm × 25 mm magnetoelastic ribbon sensor is first calibrated with fluids of known density and viscosity, and the calibrated sensor is used to estimate that the viscosity of the harvested bile is 2.7–3.7 cP. The test results presented in this paper illustrate the fundamental usability of the system when the sensor is implanted, loaded by biological fluids, and interrogated in a surgical setup.     

Histopathologic and electron microscopic characterization of cutaneous leishmaniasis in <Emphasis Type="Italic">Tatera indica</Emphasis> and <Emphasis Type="Italic">Gerbillus</Emphasis> spp. infected with <Emphasis Type="Italic">Leishmania major</Emphasis>

Cutaneous leishmaniasis (CL) is a zoonotic disease transmitted between rodents and canines, mainly by Phlebotomus sand flies and man. In southern Iran, the incidence of this protozoan disease has doubled over the last decade. The present study deals with histopathological features of CL in Tatera indica and Gerbillus spp. that participate in the epidemiology of CL in southern Iran. Thirty-two trapped rodents were evaluated for any Leishmania infection using enzyme electrophoresis and polymerase chain reaction and were concomitantly studied for any histopathological changes. Histopathological studies showed that bone marrow was the tissue of choice for light and electron microscopic study of Leishmania, demonstrating the macrophages infected with the amastigote form of the parasite. This is the first report of the histopathological detection of L. major in naturally infected T. indica and Gerbillus spp in the Larestan region.     

<Emphasis Type="Italic">In vivo</Emphasis> study of dihydroquercetin genotoxicity

Genotoxic properties of dihydroquercetin were in vivo studied by the method of chromosome aberrations counting and DNA-comet assay. Dihydroquercetin administered repeatedly (5 times, 0.15 and 1.5 mg/kg) or once in doses of 15, 150, and 2000 mg/kg induced no DNA damages in mouse bone marrow, blood, liver, and rectal cells. Single administration of this preparation in doses of 1.5 and 150 mg/kg and 5-fold administration in a dose of 1.5 mg/kg had no effect on the level of chromosome aberrations in mouse bone marrow cells. __________ Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 145, No. 3, pp. 309–312, March, 2008     

Community-acquired <Emphasis Type="Italic">Acinetobacter</Emphasis> infections

Acinetobacter infections have been attracting increasing attention during recent years because they have become common in hospitalized patients, especially in the intensive care unit (ICU) setting. However, the available literature suggests that the pathogen has another fearful potential; it can cause community-acquired infections. We searched PubMed and the reference lists of the initially identified articles and identified six case series regarding a total of 80 patients with community-acquired Acinetobacter baumannii infections; from these, 51 had pneumonia and 29 had bacteremia. Of these 80 patients, 45 (56%) died of the infection. In addition, we identified 26 case reports regarding 43 patients with community-acquired Acinetobacter infections; from these, 38 had pneumonia, two had meningitis, one had soft-tissue infection, one had ocular infection, and one had native valve endocarditis. Comorbidity was commonly present in patients reported in the case series as well as the case reports, mainly, chronic obstructive pulmonary disease, renal disease, and diabetes mellitus; heavy smoking and excess alcohol consumption were also common. Most of the studies originated from China, Taiwan, and tropical Australia. We also identified 12 retrospective or prospective studies (seven from the Far East, two from Oceania, one from N. Guinea, one from Palestine, and one from USA/Canada) that reported the frequency of community-acquired Acinetobacter infections; the range of isolation of Acinetobacter from patients with community-acquired pneumonia in these studies was 1.3%-25.9%. In conclusion, most community-acquired Acinetobacter infections have been reported from countries with tropical or subtropical climate, and mainly affect patients with some form of comorbidity or are associated with heavy smoking and excess alcohol consumption.     

Differentiating the growing nosocomial infectious threats <Emphasis Type="Italic">Ralstonia pickettii</Emphasis> and <Emphasis Type="Italic">Ralstonia insidiosa</Emphasis>

Differentiation of the growing nosocomial infectious threats, Ralstonia pickettii and Ralstonia insidiosa, based on nitrate reduction, desferrioxamine susceptibility, arabinose, N-acetyl-glucosamine and phenylacetate assimilation is described. These tests can be used for preliminary identification of Ralstonia pickettii and Ralstonia insidiosa resulting in more accurate identification of these species.     

Structural and functional analysis of <Emphasis Type="Italic">araC</Emphasis> gene in <Emphasis Type="Italic">Yersinia pestis</Emphasis> of various origins

Structural and functional analyses of the araC gene, which is involved in regulation of expression of diagnostically important characteristics, such as arabinose fermentation in the plague microbe strain, were carried out. It was established that the reason for the lack of arabinose fermentation in the altaica and hissarica subspecies and strains of talassica groups is the presence of the insertion of a single nucleotide in the araC gene at position 773 bp. The strains of the basic, caucasia, and ulegeica subspecies do not contain this mutation in the araC gene, which correlates to their ability to ferment arabinose.     

Heterogeneity of the <Emphasis Type="Italic">ospA</Emphasis> gene structure from isolates of <Emphasis Type="Italic">Borrelia garinii</Emphasis> and <Emphasis Type="Italic">Borrelia afzelii</Emphasis> from Western Siberia and Mongolia

In this work, identification and analyses of 48 full-length sequences of the ospA gene isolates of Borrelia garinii and Borrelia afzelii from Western Siberia and Mongolia has been made. It was shown that B. garinii isolates was of its high genetic heterogeneity of the ospA gene. Four genetic groups of the ospA gene from the Ixodes persulcatus tick collected in of Western Siberia and Mongolia were defined. The basic differences in the genetic variants of the ospA gene considered are seen in regions which code for antibody determinants of thhe OspA protein.     

Characterization of the siderophore transport protein AsbJ in <Emphasis Type="Italic">Aeromonas salmonicida</Emphasis> subsp. <Emphasis Type="Italic">salmonicida</Emphasis>

Iron is an important nutrient for all living systems. Bacteria have developed multiple mechanisms to obtain iron from the host. Aeromonas salmonicida subsp. salmonicida produces catechol-type siderophore under iron starvation conditions. This study attempted to characterize and ascertain the role of a siderophore ABC transporter protein AsbJ in siderophore transporter system in this bacterial pathogen. Prediction of protein domains was carried out, and deleted asbJ gene mutant strain was constructed. Results showed that this protein contains special domain related to permease and ATP-binding protein, and it is essential for the siderophore transport process in this bacterial fish pathogen.     

Chromosome pairing in allotetraploid hybrids of <Emphasis Type="Italic">Festuca pratensis</Emphasis> × <Emphasis Type="Italic">Lolium perenne</Emphasis> revealed by genomic <Emphasis Type="Italic">in situ</Emphasis> hybridization (GISH)

Genomic in situ hybridization (GISH) was used to make a detailed study of chromosome pairing at metaphase I (MI) of meiosis in six F(1) hybrid plants of the allotetraploid Festuca pratensis x Lolium perenne (2n = 4x = 28; genomic constitution FpFpLpLp). The mean chromosome configurations for all hybrids analysed were 1.13 univalents + 11.51 bivalents + 0.32 trivalents + 0.72 quadrivalents, and the mean chiasma frequency was 21.96 per cell. GISH showed that pairing was predominantly intragenomic, with mean numbers of L. perenne (Lp/Lp) and F. pratensis (Fp/Fp) bivalents being virtually equal at 5.41 and 5.48 per cell, respectively. Intergenomic pairing between Lolium and Festuca chromosomes was observed in 33.3% of Lp/Fp bivalents (0.62 per cell), in 79.7% of trivalents - Lp/Lp/Fp and Lp/Fp/Fp (0.25 per cell), and in 98.4% of quadrivalents - Lp/Lp/Fp/Fp and Lp/Lp/Lp/Fp (0.71 per cell). About 4.0% of the total chromosome complement analysed remained as univalents, an average 0.68 Lp and 0.45 Fp univalents per cell. It is evident that in these hybrids there is opportunity for recombination to take place between the two component genomes, albeit at a low level, and this is discussed in the context of compromising the stability of Festulolium hybrid cultivars and accounting for the drift in the balance of the genomes over generations. We speculate that genotypic differences between hybrids could permit selection for pairing control, and that preferences for homologous versus homoeologous centromeres in their spindle attachments and movement to the poles at anaphase I could form the basis of a mechanism underlying genome drift.     

Genetic diversity of porcine <Emphasis Type="Italic">Norovirus</Emphasis> and <Emphasis Type="Italic">Sapovirus</Emphasis>: Canada, 2005–2007

Noroviruses and sapoviruses are members of the family Caliciviridae and emerging enteric pathogens of humans and animals. Since their discovery and characterization in swine, relatively few strains have been described in detail. In order to investigate their genetic diversity, a total of 266 fecal samples collected in the province of Quebec, Canada, between 2005 and 2007 were screened for the presence of caliciviruses by RT-PCR using broadly reactive primers. Genetically heterogeneous caliciviruses were detected on the majority of farms. Typical noroviruses related to known swine genotypes were present on 20% of the farms. Sapoviruses were detected on 75% of the farms and were the most heterogeneous group. Further characterization of selected strains in their 3′ end parts was carried out for their classification and unveiled possibly new clusters of sapoviruses. No human-like noroviruses or sapoviruses were detected in the present study. GenBank accession numbers of all sequences described in this study are indicated in the figure legends.