Bartonella melophagi in Melophagus ovinus (sheep ked) collected from sheep in northern Oromia,Ethiopia

Melophagus ovinus (sheep ked) is one of the most common ectoparasites that contributes to enormous economic losses in the productivity of sheep in many countries. The present study was conducted from January 2012 to July 2013 on M. ovinus collected from sheep at three sites in Ethiopia. Of the sheep studied, 65.7% (88/134) were infested with M. ovinus. The prevalence of M. ovinus was 76% (76/100), 47% (8/17) and 23.5% (4/17) at the Kimbibit, Chacha and Shano sites, respectively. An overall number of 229 M. ovinus specimens (138 females, 86 males and five pupae) and 554 M. ovinus specimens (272 females, 282 males) were collected from young and adult sheep, respectively. Bartonella DNA was detected in 89% (694/783) of M. ovinus using a quantitative Bartonella genus-specific PCR assay targeting the 16S/23S rRNA intergenic spacer region. The sequencing of the PCR products of fragments of the gltA and rpoB genes showed 99.6–100% and 100% homology, respectively, with B. melophagi. Statistically significant variation was not noted in the overall prevalence of Bartonella DNA between female and male M. ovinus. All of the sheep infested with M. ovinus 100% (88/88) harbored at least one M. ovinus specimen that contained Bartonella DNA. This study highlights that B. melophagi in M. ovinus from sheep in highlands in Ethiopia possibly has certain zoonotic importance.     

Identification of flea species using MALDI-TOF/MS

In the present study, a molecular proteomics (MALDI-TOF/MS) approach was used as a tool for identifying flea vectors. We measured the MS spectra from 38 flea specimens of 5 species including Ctenocephalides felis, Ctenocephalides canis, Archaeopsylla erinacei, Xenopsylla cheopis and Stenoponia tripectinata. A blind test performed with 24 specimens from species included in a library spectral database confirmed that MALDI-TOF/MS is an effective tool for discriminating flea species. Although fresh and 70% ethanol-conserved samples subjected to MALDI-TOF/MS in blind tests were correctly classified, only MS spectra of quality from fresh specimens were sufficient for accurate and significant identification. A cluster analysis highlighted that the MALDI Biotyper can be used for studying the phylogeny of fleas.     

Electronic confinement and coherence in patterned epitaxial graphene

Ultrathin epitaxial graphite was grown on single-crystal silicon carbide by vacuum graphitization. The material can be patterned using standard nanolithography methods. The transport properties, which are closely related to those of carbon nanotubes, are dominated by the single epitaxial graphene layer at the silicon carbide interface and reveal the Dirac nature of the charge carriers. Patterned structures show quantum confinement of electrons and phase coherence lengths beyond 1 micrometer at 4 kelvin, with mobilities exceeding 2.5 square meters per volt-second. All-graphene electronically coherent devices and device architectures are envisaged.     

Ocular effects of topical 0.03% bimatoprost solution in normotensive feline eyes

OBJECTIVE: The current study was undertaken to evaluate the effects of topically applied bimatoprost, an ocular hypotensive lipid, on intraocular pressure (IOP) and pupil size (PS) in healthy cats. ANIMAL STUDIED: Nine European Shorthair cats free from clinically relevant ocular abnormalities were used in the study. PROCEDURES: Pretreatment baseline measurements of IOP and PS were obtained bilaterally at 8 am, 2 pm, and 8 pm for five consecutive days (days 1 to 5). Then the cats received one drop twice daily (10 am and 6 pm) of bimatoprost ophthalmic solution 0.03% (Lumigantrade mark, Allergan Inc., Irvine, CA USA), in one randomly selected eye and one drop of artificial tears in the fellow eye (control eye) for 5 days (days 6 to 10). Values for IOP and PS were obtained under the same conditions as in the pretreatment phase. The potential for ocular irritation following bimatoprost application was also evaluated. RESULTS: During the pretreatment period, the mean IOP and mean PS were not significantly different between the eyes subsequently treated with bimatoprost and those subsequently determined as controls. During the treatment period, the mean IOP in bimatoprost-treated eyes was not significantly lower than in control eyes (14.2+/-2.3 vs. 14.5+/-2.8 mmHg). Mean IOP in control eyes was not significantly changed at any time during the study period. A marked reduction of PS was seen in all bimatoprost-treated eyes, but no other clinically relevant side effects were observed. CONCLUSION: Twice daily topical applications of bimatoprost produced miosis but had no significant effect on IOP in healthy cats.     

Stability of barley and malt lipid transfer protein 1 (LTP1) toward heating and reducing agents: relationships with the brewing process

Barley lipid transfer protein (LTP1) is a heat-stable and protease-resistant albumin that concentrates in beer, where it participates in the formation and stability of beer foam. Whereas the barley LTP1 does not display any foaming properties, the corresponding beer protein is surface-active. Such an improvement is related to glycation by Maillard reactions on malting, acylation on mashing, and structural unfolding on brewing. The structural stability of purified barley and glycated malt LTP1 toward heating has been analyzed. Whatever the modification, lipid adduction or glycation, barley LTP1s are highly stable proteins that resisted temperatures up to 100 degrees C. Unfolding of LTP1 occurred only when heating was conducted in the presence of a reducing agent. In the presence of sodium sulfite, the lipid-adducted barley and malt LTP1 displayed higher heat stability than the nonadducted protein. Glycation had no or weak effect on heat-induced unfolding. Finally, it was shown that unfolding occurred on wort boiling before fermentation and that the reducing conditions are provided by malt extract.     

Mycoflora and multimycotoxin detection in corn silage: experimental study

Agricultural activities involve the use of crop preservation such as "trench-type" silo, which can sometimes be contaminated by fungi. To investigate the exposure of livestock and farm workers to fungal spores and mycotoxins, a multimycotoxin analysis method has been developed. Six mycotoxins (aflatoxin B1, citrinin, deoxynivalenol, gliotoxin, ochratoxin A, and zearalenone) were quantified by high-performance liquid chromatography coupled to mass spectrometry after solid-phase extraction. An experimental study of fungal species and mycotoxins was conducted in corn silage (Normandy, France) during 9 months of monitoring. The results indicated the recurrence of around 20 different species, with some of them being potentially toxigenic fungi such as Aspergillus fumigatus, Aspergillus parasiticus, Fusarium verticillioides, and Monascus ruber, and the detection of aflatoxin B1 (4-34 ppb), citrinin (4-25 ppb), zearalenone (23-41 ppb), and deoxynivalenol (100-213 ppb). This suggested a possible chronic exposure to low levels of mycotoxins.     

Comparison of volatile constituents of Persicaria odorata(Lour.) Soják (Polygonum odoratum Lour.) and Persicaria hydropiper L. Spach (Polygonum hydropiper L.)

Polygonum odoratum Lour. has been reclassified as Persicaria odorata (Lour.) Soják [Wilson, K. L. Polygonum sensu lato (Polygonaceae) in Australia. Telopea 1988, 3, 177-182]; other synonyms currently used are Vietnamese mint or Vietnamese coriander and, in Malaysia, Daun Laksa or Laksa plant. The aerial parts of Laksa plant are highly aromatic, and they contain many organic compounds such as (Z)-3-hexenal, (Z)-3-hexenol, decanal, undecanal, and dodecanal that are typical for green, citrus, orange peel, and coriander odors. In addition to these aldehydes, 3-sulfanyl-hexanal and 3-sulfanyl-hexan-1-ol were discovered for the first time in this herb. The fresh leaves are pungent when they are chewed, although the active compound has never been identified. The pungency of Persicaria hydropiper (L.) Spach (formerly Polygonum hydropiper L., synonym water pepper) is produced by polygodial, a 1,4-dialdehyde derived from drimane terpenoids. We also identified polygodial as the active pungent compound in P. odorata (Lour.) Soják.     

Fast and local assessment of stilbene content in grapevine leaf by in vivo fluorometry

Stilbenes are grapevine phytoalexins. These highly fluorescent molecules are generally analyzed by HPLC. This technique allows accurate assay of different stilbenes, but it is destructive, time-consuming, and neglects their spatial distribution. This is why we have tested a new method based on in vivo fluorescence using commercial spectrofluorometers that allowed fast and local assessment of stilbene content in grapevine leaves. Stilbene synthesis in grapevine Vitis vinifera var. Muscat Ottonel leaves was induced by Plasmopara viticola inoculation or UV-C irradiation. Fluorescence was measured both from the abaxial and adaxial sides of leaves, then stilbene content was analyzed by HPLC. It varied from 0 in control leaves to 15 mg g-1 dry weight in UV-treated leaves. Highly significant regressions were found between HPLC stilbene content and the corresponding leaf UV-induced blue fluorescence. Thus, in vivo fluorescence is a good tool for a rapid study of stilbenes synthesis in grapevine leaves that can potentially be extended to other fluorescent molecules.     

Reference values: a review

Abstract: Reference values are used to describe the dispersion of variables in healthy individuals. They are usually reported as population‐based reference intervals (RIs) comprising 95% of the healthy population. International recommendations state the preferred method as a priori nonparametric determination from at least 120 reference individuals, but acceptable alternative methods include transference or validation from previously established RIs. The most critical steps in the determination of reference values are the selection of reference individuals based on extensively documented inclusion and exclusion criteria and the use of quality‐controlled analytical procedures. When only small numbers of values are available, RIs can be estimated by new methods, but reference limits thus obtained may be highly imprecise. These recommendations are a challenge in veterinary clinical pathology, especially when only small numbers of reference individuals are available.     

Atypical myopathy in grazing horses: a first exploratory data analysis

Over the last decade, atypical myopathy (AM) in grazing horses has emerged in several European countries. An exploratory analysis was conducted to determine horse- and pasture-level indicators or factors associated with AM in Belgium. Belgian cases of AM confirmed by histology (n=57) were compared to their healthy co-grazing horses (n=77) and to pastured horses not involved with AM as controls (n=386). The pastures where confirmed cases were grazing (42 pastures; 38 sites; 44 incidences of AM) were compared with those of the controls (216 pastures; 96 sites; no incidence of AM). Statistically significant (P< or =0.05) exploratory variables, identified by means of adjusted odds ratios, suggested that indicators or factors associated with individual horses (young age, inactivity, body condition poor to normal), management practices (permanent pasturing, spreading of manure) and pasture characteristics (humid, sloping pastures, accumulated dead leaves, presence of waterway) may increase the risk of AM. Specific interventions based on these factors might help to reduce the incidence of AM.