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Rotavirus infections in nursing or post-weaning piglets are known to cause diarrhea, which can lead to commercial losses. Probiotic supplementation is used as a prophylactic or therapeutic approach to dealing with microbial infections in humans and animals. To evaluate the effect of probiotic bacteria on porcine rotavirus infections, non-transformed porcine intestinal epithelial IPEC-J2 cells were used as an in vitro model, and three different procedures were tested. When cells were exposed to seven probiotics at concentrations of 105, 106, or 107 CFU/mL for 16 h and removed before rotavirus challenge, infection reduction rates determined by flow cytometry were as follows: 15% (106) and 18% (105) for Bifidobacterium longum R0175, 15% (107) and 16% (106) for B. animalis lactis A026, and 15% (105) for Lactobacillus plantarum 299V. When cells were exposed to three selected probiotic strains for 1 h at higher concentrations, that is, 108 and 5 × 108 CFU/mL, before infection with rotavirus, no significant reduction was observed. When the probiotic bacteria were incubated with the virus before cell infection, a significant 14% decrease in the infection rate was observed for B. longum R0175. The results obtained using a cell-probiotics-virus platform combined with flow cytometry analysis suggest that probiotic bacteria can have a protective effect on IPEC-J2 cells before infection and can also prevent rotavirus infection of the cells.

BACKGROUND: Characterizing the multiorgan manifestations and outcomes of patients hospitalized with COVID-19 will inform resource requirements to address the long-term burden of this disease. We conducted a descriptive analysis using prospectively collected data to describe the clinical characteristics and spectrum of organ dysfunction, and in-hospital and longer-term clinical outcomes of patients hospitalized with COVID-19 during the first wave of the pandemic at a Canadian centre. METHODS: We conducted a prospective case series involving adult patients (aged ≥ 18 yr) with COVID-19 admitted to 1 of 2 hospitals in London, Ontario, from Mar. 17 to June 18, 2020, during the first wave of the pandemic. We recorded patients' baseline characteristics, physiologic parameters, measures of organ function and therapies administered during hospitalization among patients in the intensive care unit (ICU) and in non-ICU settings, and compared the characteristics of hospital survivors and nonsurvivors. Finally, we recorded follow-up thoracic computed tomography (CT) and echocardiographic findings after hospital discharge. RESULTS: We enrolled 100 consecutive patients (47 women) hospitalized with COVID-19, including 32 patients who received ICU care and 68 who received treatment in non-ICU settings. Respiratory sequelae were common: 23.0% received high-flow oxygen by nasal cannula, 9.0% received noninvasive ventilation, 24.0% received invasive mechanical ventilation and 2.0% received venovenous extracorporeal membrane oxygenation. Overall, 9.0% of patients had cerebrovascular events (3.0% ischemic stroke, 6.0% intracranial hemorrhage), and 6.0% had pulmonary embolism. After discharge, 11 of 19 patients had persistent abnormalities on CT thorax, and 6 of 15 had persistent cardiac dysfunction on echocardiography. INTERPRETATION: This study provides further evidence that COVID-19 is a multisystem disease involving neurologic, cardiac and thrombotic dysfunction, without evidence of hepatic dysfunction. Patients have persistent organ dysfunction after hospital discharge, underscoring the need for research on long-term outcomes of COVID-19 survivors.

To evaluate the impact of the COVID-19 pandemic on Canadian intensive care unit (ICU) workers.Between June and August 2020, we distributed a cross-sectional online survey of ICU workers evaluating the impact of the pandemic, coping strategies, symptoms of post-traumatic stress disorder (PTSD; Impact of Events Scale-Revised), and psychological distress, anxiety, and depression (Kessler Psychological Distress Scale). We performed regression analyses to determine the predictors of psychological symptoms.We analyzed responses from 455 ICU workers (80% women; 67% from Ontario; 279 nurses, 69 physicians, and 107 other healthcare professionals). Respondents felt that their job put them at great risk of exposure (60%), were concerned about transmitting COVID-19 to family members (76%), felt more stressed at work (67%), and considered leaving their job (37%). Overall, 25% had probable PTSD and 18% had minimal or greater psychological distress. Nurses were more likely to report PTSD symptoms (33%) and psychological distress (23%) than physicians (5% for both) and other health disciplines professionals (19% and 14%). Variables associated with PTSD and psychological distress included female sex (beta-coefficient [B], 1.59; 95% confidence interval [CI], 1.20 to 2.10 and B, 3.79; 95% CI, 1.79 to 5.78, respectively; P0.001 for differences in scores across groups) and perceived increased risk due to PPE shortage or inadequate PPE training (B, 1.87; 95% CI, 1.51 to 2.31 and B, 4.88; 95% CI, 3.34 to 6.43, respectively). Coping strategies included talking to friends/family/colleagues (80%), learning about COVID-19 (78%), and physical exercise (68%). Over half endorsed the following workplace strategies as valuable: hospital-provided scrubs, clear communication and protocols by hospitals, knowing their voice is heard, subsidized parking, and gestures of appreciation from leadership.This survey study shows that ICU workers have been impacted by the COVID-19 pandemic with high levels of stress and psychological burden. Respondents endorsed communication, protocols, and appreciation from leadership as helpful mitigating strategies.RéSUMé: OBJECTIF: Évaluer l’impact de la pandémie de COVID-19 sur les travailleurs canadiens des unités de soins intensifs (USI). MéTHODE: Entre juin et août 2020, nous avons fait parvenir un sondage transversal en ligne aux travailleurs des soins intensifs pour évaluer l’impact de la pandémie, les stratégies d’adaptation et les symptômes de stress post-traumatique (SPT; Échelle révisée de l’impact de l’événement - IES-R), ainsi que la détresse psychologique, l’anxiété et la dépression (Échelle de détresse psychologique de Kessler). Nous avons réalisé des analyses de régression pour déterminer les prédicteurs de symptômes psychologiques. RéSULTATS: Nous avons analysé les réponses de 455 travailleurs des soins intensifs (80 % de femmes; 67 % de l’Ontario; 279 infirmières/infirmiers, 69 médecins et 107 autres professionnels de la santé). Les répondants ont estimé que leur emploi les plaçait face à un risque élevé d’exposition (60 %), craignaient de transmettre la COVID-19 aux membres de leur famille (76 %), se sentaient plus stressés au travail (67 %) et avaient envisagé de quitter leur emploi (37 %). Dans l’ensemble, 25 % souffraient probablement d’un SPT et 18 % présentaient une détresse psychologique minimale ou supérieure. Les infirmières et infirmiers étaient plus susceptibles de rapporter des symptômes de SPT (33 %) et de détresse psychologique (23 %) que les médecins (5 % pour les deux) et les professionnels de la santé des autres disciplines (19 % et 14 %). Les variables associées à un SPT et à la détresse psychologique comprenaient le sexe féminin (coefficient bêta [B], 1,59; intervalle de confiance [IC] à 95 %, 1,20 à 2,10 et B, 3,79; IC 95 %, 1,79 à 5,78, respectivement; P0,001 pour les différences de scores entre les groupes) et la perception d’un risque accru en raison des pénuries d’EPI ou d’une formation inadéquate en EPI (B, 1,87; IC 95 %, 1,51 à 2,31 et B, 4,88; IC 95 %, 3,34 à 6,43, respectivement). Les stratégies d’adaptation comprenaient le fait de parler aux amis, à la famille ou aux collègues (80 %), l’acquisition de connaissances concernant la COVID-19 (78 %) et l’exercice physique (68 %). Plus de la moitié ont estimé que les stratégies de travail suivantes étaient utiles : des uniformes fournis par les hôpitaux, une communication et des protocoles clairs de la part des hôpitaux, le fait de savoir que leur voix est entendue, un stationnement subventionné et des gestes d’appréciation de la part des dirigeants. CONCLUSION: Cette étude montre que les travailleurs des soins intensifs ont été touchés par la pandémie de COVID-19 avec des niveaux élevés de stress et de fardeau psychologique. Les répondants ont déclaré que la communication, les protocoles et les gestes d’appréciation de la direction constituaient des stratégies d’atténuation utiles.

The presence of enteric viruses on fresh berries poses a health risk to consumers. After berries are picked, a washing step can reduce microbial counts on fruit surfaces to increase their safety. This study compared the effectiveness of tap water, commercial solutions of fruit and vegetable sanitizer composed of peroxyacetic acid and hydrogen peroxide (PAA) and neutral electrolyzed oxidizing water (NEW) for washing fresh blueberries that had been inoculated with either murine norovirus (MNV-1), bacteriophage MS2, bovine rotavirus (boRV) or hepatitis A virus (HAV). Initially, inactivation levels were measured after blueberries were washed for 1, 3, 5, 10 and 20 min. Subsequently, the effect of combining up to three sequential 1-min washes was evaluated. Washes with water lasting up to 20 min reduced MNV-1, MS2 and HAV populations by 1–2 log10 (PFU) and boRV by less than 4 log10. Increasing washing time did not have a significant effect, except where NEW washes were increased by up to 3 min for MS2 and by 10 min for boRV, with viral titers decreasing by > 4 log10 and >5 log10, respectively. Viral counts were further reduced through additional washes as follows: reduction of MS2 with water, of MNV-1 with NEW and HAV with PAA. PAA achieved significant and rapid inactivation of boRV (>6 log10 PFU after 1 min), MNV-1 (>4 log10 after 10 min) and MS2 (>3 log10 after 3 min). HAV was moderately affected ( 4 log10 after 1 min), MS2 (>4 log10 after 3 min) and HAV (>4 log10 after 1 min). For boRV, washing time needed to be increased to 10 min or three sequential washes were needed to reach >5 log10 reduction. These results highlight the efficiency of PAA at reducing infectivity of MNV-1, MS2 bacteriophage and boRV, and NEW to inactivate the four viruses.

Southwestern Alberta is a region of Canada that has high rates of enteritis as well as high densities of livestock. The presence of enteric RNA viruses, specifically norovirus (NoV) GI, GII, GIII, GIV; sapovirus (SaV); rotavirus (RV); and astrovirus (AstV), was evaluated in stools from diarrheic (n = 2281) and non-diarrheic (n = 173) people over a 1-year period in 2008 and 2009. Diarrheic individuals lived in rural (46.6 %) and urban (53.4 %) settings and ranged in age from less than 1 month to 102 years, and the highest prevalence of infection in these individuals was in November. In all, viruses were detected in diarrheic stools from 388 individuals (17.0 %). NoV GII was the most frequently detected virus (8.0 %; n = 182) followed by SaV (4.3 %; n = 97), RV (2.0 %; n = 46), AstV (1.8 %; n = 42), NoV GI (0.9 %; n = 20), and NoV GIV (0.1 %; n = 1). Animal NoV GIII was never detected. The prevalence of mixed viral infections in diarrheic individuals was 2.8 % (n = 11). Children from 1 to 5 years of age accounted for the highest prevalence of positive stools, followed by the elderly individuals (≥70 years). Only NoV GII (1.2 %; n = 2) and SaV (1.2 %; n = 2) were detected in stools from non-diarrheic people. Sequence analysis of a subset of stools revealed homology to NoV, SaV and RV sequences from humans but not to strains from non-human animals. The results of this study do not support the hypothesis that viruses of animal origin have a significant impact on the occurrence of acute gastroenteritis caused by RNA enteric viruses in people living in southwestern Alberta.

The viability of murine norovirus (MNV-1), bovine rotavirus (boRV), and hepatitis A virus (HAV) was evaluated at 21 °C, 4 °C, and −20 °C on stainless steel surfaces, in bottled water, and on blueberries for up to 21 days. After 14 days of incubation at 21 °C on stainless steel, a viability loss >4 log for MNV-1, >8 log for boRV, and >1 log for HAV was observed. Losses were observed for MNV-1 (>1 log) and HAV (>2 log) incubated in water at 21 °C for 21 days. No significant loss was detected for MNV-1 and HAV at 4 °C and −20 °C and for boRV at 21 °C, 4 °C, and −20 °C. On blueberries incubated at 4 °C and −20 °C, they all maintained their infectivity. After 7 days at 21 °C, a loss >2 log, a loss of 3 log, and no loss were observed for boRV, MNV-1, and HAV, respectively. After RNase pretreatment, the detection of extracted RNA from infectious and noninfectious samples suggested the protection of RNA inside the capsid. Even though they all are enteric viruses, their persistence varied with temperature and the nature of the commodity. It is therefore important to use more than one viral surrogate, during inactivation treatments or implementation of control measures.

Torque teno virus (TTV) is a small virus belongs to Anelloviridea family. TTV is a disease orphan virus but it has often been associated with a variety of pathologies and co-infections. TTV was recently identified as an infectious agent that could potentially be involved in cases of acute enteritis.To ascertain the presence of TTV in stools from diarrheic and not diarrheic people, and to investigate an association between infection, and patient age and gender.Stool samples from people exhibiting signs of enteritis (954) and from non-diarrheic individuals (76) were collected in the former Chinook Health Region (CHR) in Southwestern Alberta, Canada from May 2008 to April 2009. Viral genetic material was extracted, and detection and quantification of TTV were carried out by real-time PCR. The presence of other viral and bacterial enteric pathogens was also investigated.More (P0.001) diarrheic people (38.8%) tested positive for TTV DNA than non-diarrheic individuals (18.4%). Furthermore, viral load was greater (P0.001) in stools from diarrheic (2.0×10(7)copies/g) than non-diarrheic (2.0×10(3)copies/g) people. TTV DNA was detected most often in diarrheic individuals that were 0-5 (57.3%) and greater than 81 (59.0%) years of age. Combined across age, the prevalence of TTV was higher among men than women (P=0.003). Co-infections with other enteric pathogens were observed.This study revealed a significant association between TTV prevalence and viral load, and enteritis. Also, TTV prevalence was significantly higher in the very young and elderly suggesting that immunological status is important.

We collected 599 Canadian retail pork chops and 283 pork livers routinely (usually weekly) from April 2011 to March 2012 using the Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS) retail sampling platform. Samples were assayed using validated real-time (q) reverse transcriptase polymerase chain reaction (RT-PCR) and nested classical RT-PCR for the detection of hepatitis E virus (HEV), porcine enteric calicivirus (PEC) and rotavirus (RV). The presence of Escherichia coli, Salmonella spp. and Campylobacter spp. was measured on a subset of our samples. Exact logistic regression models were fitted for predictors for HEV detection, for each assay. For both assays, sample type (pork chop versus liver) was a significant predictor for HEV RNA detection. For nested classical RT-PCR but not qRT-PCR, region of sample collection was a significant predictor (P = 0.008) of HEV detection. Odds of HEV detection were greatest in spring relative to other seasons. E. coli was a significant predictor for HEV RNA detection using the qRT-PCR (P = 0.03). Overall, the prevalence of E. coli, Salmonella spp. and Campylobacter spp. was significantly greater than HEV, PEC or RV on our retail pork samples. Our sparse data set for the detection of PEC and RV precluded modelling of risk factors for the detection of these viruses.

Among Canadian swine HEV strains, only one complete genome sequence has been published so far, and there are no data on the virulence of these strains. A collection of 28 Canadian swine HEV strains was used in this study. After RNA extraction, a portion of ORF2, the 3’ end of the helicase domain, and two complete genomes were amplified and sequenced. These two new Canadian complete genomes belonged to two different subtypes and showed 87.5 and 87.7 % sequence identity to the Canadian swine HEV strain Arkell. The V239A substitution within the helicase domain, which is associated with increased virulence of genotype 3 HEV, was detected in one Canadian swine HEV strain. However, no human hepatitis E infections have been associated with this strain.

Over the past 15 years, hepatitis E virus (HEV), norovirus (NoV), and rotavirus (RV) have been hypothesized to be potentially zoonotic; swine and pork have been suggested as possible human infection sources for all 3 viruses. Our objective was to estimate HEV, NoV, and RV prevalence and load on Canadian retail pork chops and livers. Using the Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS) sampling platform, pork livers (n = 283) and chops (n = 599) were collected, processed, and assayed for the 3 viruses by four collaborating federal laboratories using validated real time reverse transcriptase polymerase chain reactions (qRT-PCR). Follow-up qRT-PCR estimating viral load in genomic copies/g was followed by nested classical RT-PCR and isolate sequencing of a partial segment of the ORF2 gene. Local alignments were performed using MUSCLE (Multiple Sequence Comparison by Log-Expectation); a phylogenetic tree was created. Twenty-five livers and 6 chops were classified ‘positive’ (thresholds for viral RNA detected in both replicates of the assay) or ‘suspect’ (thresholds detected in one of two replicates) for HEV. Follow-up qRT-PCR detected HEV on 16 livers, 0 chops, and nested classical RT-PCR, on 14 livers and 0 chops. Initial qRT-PCR classified 12 chops ‘suspect’ for NoV. Follow-up qRT-PCR detected viral RNA on only one sample with thresholds greater than 40 in both replicates. No amplicon was yielded, and therefore no isolate was sequenced from this sample. Partial ORF2 genes from 14 HEV isolates were sequenced, and compared via sequence identity and phylogenetic analysis with selected human case isolates listed in NCBI-GenBank. Overall, HEV prevalence on retail pork was comparable with other published reports.

Chilled meat exportation comprises chilling within 48 h post-mortem to temperatures

Aims: To demonstrate that produce rinsates used for RT-qPCR detection of foodborne viruses may cause significant PCR inhibition and propose a means to reduce its impact on sensitivity. Methods and Results: Here, it is shown that rinsing and concentration from spinach and precut lettuce have the potential to generate RNA extracts that are inhibitory to RT-qPCRs assembled from commercial kits for the detection of norovirus GII (NoV GII), hepatitis A virus (HAV), hepatitis E virus (HEV), rotavirus (RV) and feline calicivirus (FCV) as sample process control. It is further shown that the addition of bovine serum albumin (BSA) to those reactions restored a positive signal in all cases. The effect of BSA was dependent upon the primer/probe combination. Moreover, two of the detection systems (FCV and HAV) strongly benefited from the addition of BSA even in the absence of PCR inhibitors. Conclusions: BSA was shown to restore positive signals in five different RT-qPCR systems that were otherwise completely inhibited by produce rinsate extracts. It is therefore suggested to consider the addition of BSA to RT-qPCRs for the detection of foodborne viruses when inhibition is observed. Significance and Impact of the Study: This study clearly demonstrates the potency of PCR inhibitors generated during routine virus concentration from produce and that it can be alleviated by the addition of BSA to the RT-qPCRs. Although used elsewhere, the addition of BSA to PCRs is not a common practice in this growing field of research.

Substantial numbers of aerobic bacteria but few coliforms or Listeria spp. and no Escherichia coli were recovered from both swab samples and brines circulated in cleaned equipment used for injecting pork loins. After meat was processed for 30 or 60 min, the numbers of aerobic bacteria in brines had increased by >1 log unit, to about 4.5 log cfu ml −1 , but coliforms were E. coli and Listeria spp. were −1 . The numbers of bacteria on the surfaces of pork loins before and after injection of the meat were similar. No bacteria were recovered from the deep tissues of the uninjected meat, but aerobic bacteria were recovered at log-mean numbers of 2.1 log cfu g −1 and coliforms at log-total numbers of 1.2 log cfu 25 g −1 from 25 samples of deep tissues of injected meat. Aerobic bacteria were recovered at log total numbers of 1.0 log cfu 25 g −1 from 25 samples of injected pork cooked to a central temperature of 61 °C, but no bacteria were recovered from the deep tissues of meat cooked to 70 °C. The findings suggest that moisture-enhanced pork cooked to a medium rare condition can be microbiologically safe.

Lipases (triacylglycerol acylhydrolase, EC 3.1.1.3) are part of the family of hydrolases that act on carboxylic ester bonds. The physiologic role of lipases is to hydrolyze triglycerides into diglycerides, monoglycerides, fatty acids, and glycerol. These enzymes are widely found throughout the animal and plant kingdoms, as well as in molds and bacteria. Of all known enzymes, lipases have attracted the most scientific attention. In addition to their natural function of hydrolyzing carboxylic ester bonds, lipases can catalyze esterification, interesterification, and transesterification reactions in nonaqueous media. This versatility makes lipases the enzymes of choice for potential applications in the food, detergent, pharmaceutical, leather, textile, cosmetic, and paper industries. The most significant industrial applications of lipases have been mainly found in the food, detergent, and pharmaceutical sectors. Limitations of the industrial use of these enzymes have mainly been owing to their high production costs, which may be overcome by molecular technologies, enabling the production of these enzymes at high levels and in a virtually purified form.

The temperatures and ages of 5389 packs of beef in 10 multiple shelf display cabinets were determined. The median temperature of the packs in each cabinet was 7 °C. All packs in three cabinets were ⩽2 days old. The percentages of packs older than 2 days were

The halonium metathesis reaction of ketones and aldehydes, C=O + XF + → C=F + + X=O is difficult to harness for three reasons: (1) the interchange of F + for O is so exothermic that the C=F + product ion often decomposes further; (2) the adduct of XF + to the carbonyl oxygen frequently undergoes side reactions to the virtual exclusion of metathesis; and (3) the metathesis ion is liable to rearrange to a mixture of isomers. Several approaches have been explored to make this reaction a useful source of gaseous fluoroalkyl cations. DFT calculations reinforce the intuition that cyclopentenone should give a good yield of metathesis ions in its ion–molecule reaction with CF3 + , an expectation that is borne out by experiment. Other approaches have met with less dramatic success. Variation of XF + gives a number of interesting results, but little improvement over CF3 + . Deuterium substitution at the carbon adjacent to the carbonyl (-position) does not restrain further decomposition, but deuteration of the next carbon (-position) does appear to do so. The isotopic labeling experiments indicate that the prevalent mode of decomposition requires hydrogen shift followed by a 1,3-elimination of HF. Observed side reactions of adduct ions include alkene expulsion to yield CF3-containing products (such as m/z 125 from the reaction of cycloalkanones with CF3 + ) and direct elimination of HF (as conjectured for the reaction of CFO + with diethyl ketone, with concurrent loss of CO2). Structures of ion–molecule reaction products can be reliably inferred only when the expected mechanism yields the minimum energy structure for that molecular formula. (Int J Mass Spectrom 222 (2003) 451–463) © 2002 Published by Elsevier Science B.V.

In the cell of an FT-ICR spectrometer, (CH3)(X)C(OCR)( + OHR ′ ) and (CH3)(X)Si(OCR) + OHR ′ (R and R′=H, CH3 or C2H5; X=H or CH3) covalent ions were generated by reaction of the (CH3)(X)+SiOCR′ cations with water or alcohols. In the so-formed covalent ions, experiment shows that 1,3-H+ transfers from oxygen to oxygen are often easy in silicon containing ions while they are not observed in the corresponding ions containing only carbon. Calculations indicate that the energy required for a 1,3-H+ transfer from oxygen to oxygen is almost identical whether the transition state contains a silicon atom or not. The greater strength of the SiO bond in cations, compared to that of the CO bond or, in other words, the great electrophilic character of cations possessing a Si+, is the main factor explaining the difference in the behavior of the studied silicon containing ions and ions containing exclusively carbon.

Products of the F+-for-O metathesis between a variety of fluorinated cations and α,β-unsaturated ketones have been examined using FT-ICR and sector mass spectrometry. The reactant ions CF3+, C3F7+, and CFO+ all undergo ion–molecule reactions with carbonyl compounds to replace oxygen with F+. In principle, the simple transposition of atoms corresponds to the transformation  C  O → C  F + and ought to produce monofluorinated allylic cations, which DFT calculations predict to be highly stable. The metathesis, however, is so exothermic that cationic rearrangements take place, as attested by several experimental data, including: (1) unimolecular loss of HF from the ion created by methacrolein; (2) the Bronsted acidity of the ion created by methacrolein in its subsequent ion–molecule reactions; and (3) unimolecular loss of ethylene from the ion created by senecialdehyde. DFT calculations suggest that cyclization of unsaturated cations takes place, even though that mechanism removes the positive charge from conjugation with double bonds. Evidence for cyclization is to be found in CF3+-adduct ions as well as the metathesis ions (for instance, the reaction of sorbital with CF3+, which forms CH2OCF3+, as well as the metathesis ion). Electrocyclic ring closure of fluoroallylic ions creates cyclopropyl cations, which represent transition states rather than stable structures on the DFT potential energy surface. Calculated energy barriers to forming monofluorinated cyclopropyl cations range from ΔH=160 to 266 kJ mol−1. The exothermicities of metatheses with CF3+ are calculated to be >50 kJ mol−1 higher than the respective barrier heights.

Waters Silica Sep-Pak cartridges were evaluated for their performance in trapping short chain fatty acid ethyl esters. Liquid solutions of ethyl butyrate, ethyl valerate and ethyl caproate were injected onto cartridges. All the esters bound to the matrix and were eluted with four bed volumes of ethanol for ethyl butyrate and two bed volumes of ethanol for ethyl valerate and ethyl caproate. Samples of esters stripped with an air stream for 1 min and trapped on cartridges were found to vary by less than 8% for ethyl propionate, ethyl butyrate, ethyl valerate and ethyl caproate. Production of ethyl butyrate by Pseudomonas fragi CRDA 037 resting cells during biotransformation was efficiently evaluated using these cartridges. Variations between samples were found to be less than 10%. © 2000 Society of Chemical Industry

After selection from eight yeast commercial or type strains based on their aromatic potential to valorize bread by-products, Geotrichum candidum ATCC 62217 formed fruity aroma compounds (pineapple-like) on fermented waste bread (35% white bread crumb and 65% water). Fatty acids esters were identified, including ethyl esters of acetic acid, propionic acid, butyric acid and isobutyric acid. Their production corresponded to the stationary growth phase of the strain and, after 48 h, it was improved by agitation and, to a lesser extent, at 30°C compared to 25 or 20°C. Aromatic properties of the strain were linked to its ability to metabolize organic acids.

In the gas phase, (CH(3))(3)SiOSi(+)(CH(3))(2) and (CH(3))CH(2)SiOSi(+)(CH(3))(2) ions 1 and 2 were formed in the external source of a Fourier transform ion cyclofrom resonance (FT-ICR) spectrometer by electron impact ionization of (CH(3))(3)SiOSi(CH(3))(3). In the FT-ICR cell, the electrophilic center of these ions reacts with acetone to give product ions whose structures are probed by comparison with those of the products formed by reaction with water. The mechanisms of formation of these products, studied by labeling, involve facile 1,3-methyl transfer from silicon to silicon and cyclic intermediates. Copyright 1999 John Wiley & Sons, Ltd.

Molecules containing a benzene ring and an oxygen atom typically have two types of protonation sites: on the ring (where facile intramolecular hydrogen transposition from carbon to carbon probably takes place) or on an oxygen lone pair. Four aryl ethers are compared: the isomers phthalan (1, a cyclic benzylic ether) and coumaran (2, a cyclic phenyl ether), as well as isochroman (3) and isopropyl phenyl ether (iPrOPh). The proton affinities of 1–3 have been measured using FT-ICR techniques as 830, 855 and 838 kJ/mol, respectively. Comparison with model compounds and Hartree-Fock-based SCF calculations indicate that protonated phthalan (1H) and protonated isochroman (3H) have O-protonated structures. By contrast, the conjugate acids of coumaran and iPrOPh prefer ring-protonated structures. Acidification/neutralization experiments in the ICR, as well as MIKE spectra, demonstrate that chemical ionization of iPrOPh produces noninterconverting O- and ring-protonated forms. Metastable ion decompositions of protonated phthalan and protonated isochroman give evidence of separate decomposition pathways for both types of tautomers. Protonated coumaran exhibits complete randomization of hydrogen between oxygen and the ring, which is attributed to high barriers for expulsion of neutral fragments.

In the gas phase, the (CH 3 )) 3 SSiOSi(CH 3 )) 2 + and (CH 3 )) 2 SSi + OOSi(CH 3 ))CH 2 ions were formed in the external source of a FT-ICR mass spectrometer by fragmentation of (CH 3 )) 3 SSiOSi(CH 3 )) 3 + . In the c. In the cell, the electrophilic center of these ions reacts with water to give product-ions which undergo, spontaneously or upon collision, sequential losses of methane and water. The reactions of D 2 OO and H 2 8 OO indicate that a permutation of the oxygen atom of the reactant and that of water takes place prior to the dissociation of the productions. This means that both oxygens play a symmetric role in an intermediate step of the reaction pathway.

The proton affinities of 2(5H)-furanone, 1 (836 kJ/mol), 5,6-dihydro-2H-pyran-2-one, 2 (862 kJ/mol), cyclopentenone, 3 (857 kJ/mol), and cyclohexenone, 4 (863 kJ/mol), have been measured by Fourier transform ion cyclotron resonance techniques. A comparison is made with (reexamined) data concerning saturated cyclic and unsaturated aliphatic analogs. Three general observations are made. First, the basicity is found to increase with the size of the ring. Second, unsaturated lactones are more basic than their corresponding aliphatic unsaturated esters. Third, unsaturated and saturated lactones have almost identical gas-phase basicities, while unsaturated and saturated lactones have almost identical gas-phase basicities, while unsaturated cyclic ketones are more basic than their saturated analogs. All these experimental findings have been rationalized by means of ab initio calculations up to the G2(MP2,SVP) level. The basicity trends along the series are the result of two main factors: the different hybridization pattern of the carbonyl carbon as the size of the ring changes and, in the case of lactones, the nonbonding interaction between the proton attached to the carbonyl group and the ether-like oxygen which contributes to the enhanced stability of the protonated form. For unsaturated ketones the C=C double bond participates fully in the change in charge distribution induced by the protonation, while for unsaturated lactones the existence of an oxygen atom within the ring impedes this shift of the electron density.

Cyclic amide amidohydrolases are important biocatalysts for the in vitro synthesis of chiral amino acids. This paper is the first description of the occurrence of three cyclic amide amidohydrolase activities in hulls, by-products of pea crop. Partial purification of these cyclic amide amidohydrolases extracted from hulls of Pisum sativum revealed the presence of dihydropyrimidinase, d -hydantoinase and l -hydantoinase activities. Our study shows that diversity of cyclic amide amidohydrolases also exists in plants such as legume seeds, since cyclic amide amidohydrolases from pea hulls were shown to hydrolyse dihydrouracil, hydantoin, l -MMEH and dl -MMEH.

Torque teno viruses (TTV) are widespread in humans, swine as well as in several other animal species. In market ready swine, the reported prevalence ranges between 11% and 100%. Through a national retail sampling plan from the Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS) program, 283 and 599 liver and pork chop samples, respectively, were collected over a 12-month period from commercial establishments in 5 selected geographical regions of Canada to assess the presence of Torque teno sus viruses (TTSuVs) in these products. TTSuVs were detected in 97.9% of pork chops with viral loads ranging between 1×10(4) and 9.9×10(5) genomic copies (gc)/g and 98.6% of liver samples with viral loads ranging from 1×10(5) to 9.9×10(6) gc/g. A selection of 20 positive samples (10 pork chop and 10 liver) from the 5 geographical regions were further tested for the production, of a 305bp fragment for TTSuV1 and a 253bp fragment for TTSuV2 in the non-coding region. TTSuV1 was present in all 10 liver and 10 pork chops samples while TTSuV2 was detected in 10 liver and 9 pork chop samples. Two different TTSuV1 sequences were simultaneously detected from 5 of 20 samples and 2 different TTSuV2 sequences were detected from 6 of 19 samples. The omnipresence of TTSuVs in commercial pork samples may allow its use as a viral indicator to monitor the effectiveness of cleaning and disinfecting process in slaughtering, cutting, slicing and packaging facilities.

The proton affinity at the heteroatom PAX of four α-radicals (CH2OH, CH3CHOH, CH2OCH3 and CH2NH2) was measured by studying the deprotonation of the corresponding α-distonic ions in the cell of a FTICR spectrometer. This method can only be used for α-distonic ions which are more stable than their molecular ion counterpart. It was found that the PAX of the CH2OH, CH3CHOH, CH2OCH3 and CH2NH2 α-radicals lies respectively 15.7, 14.5, 10.1 and 17.2 kcal mol−1 under that of CH3OH, CH3CH2OH, CH3OCH3 and CH3NH2. These results are in good agreement with the PA obtained by high level ab initio calculations.

For the proton transfer reaction [MH]+ + B → M + [BH]+ (I) a correlation is observed between the experimental reaction rate kexp and the standard free energy variation ΔG°. This correlation may be described by a relationship of the type k exp /k coll = 1 [1 + exp (ΔG° + G a °)/RT] where kcoll is the collision rate constant and ΔGa° an apparent energy barrier for reaction (I). It is found that ΔGa° is of the same order as RT and thus the preceding relationship allows the determination of unknown gas-phase basicities. Implications for the use of the “bracketing” and the “kinetic” methods are discussed.

The reaction of the ˙CH2CH2OHCH3+ distonic ion with CH2O was studied by Fourier transform ion cyclotron resonance spectrometry. The process is induced by an initial regiospecific attack of the carbon CH2O at the radical site of the distonic ion, leading to an intermediate adduct ion which loses water. The mechanism was demonstrated by labelling, by studying the structure of the product ion and by examining independently the behaviour of the putative intermediate radical cation.

Enterobacter agglomerans isolated from a soil sample collected in the vicinity of a sugar house was grown on low-grade maple sap. When cultivated in shake flask, Ent. agglomerans produced exopolysaccharide and α-ketoglutarate. No polysaccharide and no α-ketoglutarate were produced during growth at dissolved oxygen concentrations lower than 1% saturation in a 3.51 bioreactor, but succinate, lactate and formate were accumulated. In order to increase polysaccharide production, various agitation systems were adapted to 7 1 bioreactors with working volumes of 4 1. Highest polysaccharide yield (Y p/s = 0.70) and biomass yield ( Y x/s = 0.17) were obtained with bioreactors agitated with four- and six-bladed Rushton turbines. Accumulation of mixed organic acids during polysaccharide production indicated that both aerobic and anaerobic conditions prevailed inside the bioreactors. Maple sap concentration higher than 60 g l -1 (as sucrose equivalent) decreased both growth and exopolysaccharide production.

Pseudomonas putida strain DSM 84 produces N-carbamyl-D-amino acids from the corresponding D-5-monosubstituted hydantoins. The sequence of the D-hydantoinase gene from this strain (GenBank accession number L24157) was used to develop a DNA probe of 122 base pairs (bp) that could detect D-hydantoinase genes in other bacterial genera by DNA and by colony hybridization. Under conditions tolerating 32% mismatch, the probe was specific for all strains that expressed D-hydantoinase activity. These include Pseudomonadaceae of all rRNA groups, and bacteria belonging to the genera Agrobacterium, Serratia, Corynebacterium, and Arthrobacter. Environmental sampling was simulated by screening a mixture of unknown microorganisms from commercial inocula for the biodegradation of industrial, municipal and domestic wastes. The 122-bp probe was specific for microorganisms that subsequently demonstrated D-hydantoinase activity. Bacterial species from four different genera were detected, which were Pseudomonas, Klebsiella, Enterobacter, and Enterococcus.

Aims The aim of this study was to compare the performance of four RT-qPCR assays for the detection of human and bovine group A rotaviruses and to characterize the positive samples by sequence analysis of VP4 and VP7 genes. Methods and Results RNA extracted from eight human rotavirus strains, and a panel of 33 human and 25 bovine faecal samples was subjected to different RT-qPCR detection systems. Among these assays, only RT-qPCR primers and probe systems B and C were able to detect all human rotavirus strains from cell culture solutions and faecal samples. However, the results showed that the system C was generally more sensitive by one or two logs than the other RT-qPCR assays tested. With the bovine faecal samples, the most efficient RT-qPCR systems were B and A with the detection in 100 and 92% of samples tested, respectively. Human group A rotavirus G1P[8] and bovine G6P[11] were the most frequently used strains identified in this study. A G3P[9] strain, closely related to a feline rotavirus isolated in the USA, was also discovered in a human rotavirus infection. Conclusion The RT-qPCR system B was the only TaqMan assay evaluated in this study able to detect rotavirus RNA in all positive human and bovine faecal samples. Significance and Impact of the Study Utilization of only one RT-qPCR for the detection of human and bovine group A rotaviruses and the possibility of human infection by a feline rotavirus strain.

Background Haemozoin crystals, produced by Plasmodium during its intra-erythrocytic asexual reproduction cycle, can generate UV light via the laser-induced, non-linear optical process of third harmonic generation (THG). In the current study the feasibility of using haemozoin, constitutively stored in the parasite’s food vacuole, to kill the parasite by irradiation with a near IR laser was evaluated. Methods Cultured Plasmodium parasites at different stages of development were irradiated with a pulsed NIR laser and the viability of parasites at each stage was evaluated from their corresponding growth curves using the continuous culture method. Additional testing for germicidal effects of haemozoin and NIR laser was performed by adding synthetic haemozoin crystals to Escherichia coli in suspension. Cell suspensions were then irradiated with the laser and small aliquots taken and spread on agar plates containing selective agents to determine cell viability (CFU). Results Parasites in the late-trophozoites form as well as trophozoites in early-stage of DNA synthesis were found to be the most sensitive to the treatment with ~4-log reduction in viability after six passes through the laser beam; followed by parasites in ring phase (~2-log reduction). A ~1-log reduction in E. coli viability was obtained following a 60 min irradiation regimen of the bacteria in the presence of 1 μM synthetic haemozoin and a ~2-log reduction in the presence of 10 μM haemozoin. Minimal (≤15%) cell kill was observed in the presence of 10 μM haemin. Conclusions Laser-induced third-harmonic generation by haemozoin can be used to inactivate Plasmodium. This result may have clinical implications for treating severe malaria symptoms by irradiating the patient’s blood through the skin or through dialysis tubing with a NIR laser.

Little is known about the role of herpes simplex virus (HSV) type 1 (HSV1) in the epidemiology of genital herpes in Canada. Data on herpes viral cultures for two consecutive years obtained from L'Hôpital Dr GL Dumont, which performs all the viral culture testing in New Brunswick, were reviewed. It was hypothesized that HSV1 was the main cause of genital herpes in New Brunswick.Samples of genital origin sent to the laboratory for HSV culture testing between July 2006 and June 2008 were analyzed. Samples from an unspecified or a nongenital source were excluded from analysis. Multiple positive samples collected from the same patient were pooled into a single sample.HSV was isolated from 764 different patients. HSV1 was isolated in 62.6% of patients (male, 55%; female, 63.8%). HSV1 was isolated in 73.2% of patients 10 to 39 years of age and in 32% of patients ≥40 years of age. The difference in rates of HSV1 infection between the 10 to 39 years of age group and the ≥40 years of age group was statistically significant (P0.001 [χ(2)]). In a similar Canadian study performed in Nova Scotia, HSV1 was recovered in 53.7% of positive cultures (male, 36.7%; female, 58.1%). The rates of HSV1 infection reported by this study and the present study were significantly different (P0.001 [χ(2)] for male, P=0.012 for female).In New Brunswick, HSV1 is the dominant type of HSV isolated in samples collected from a genital site. Significant rate differences were demonstrated between the groups 10 to 39 years of age and ≥40 years of age.Little is known about the role of herpes simplex virus (HSV) type 1 (HSV1) in the epidemiology of genital herpes in Canada. Data on herpes viral cultures for two consecutive years obtained from L’Hôpital Dr GL Dumont, which performs all the viral culture testing in New Brunswick, were reviewed. It was hypothesized that HSV1 was the main cause of genital herpes in New Brunswick.Samples of genital origin sent to the laboratory for HSV culture testing between July 2006 and June 2008 were analyzed. Samples from an unspecified or a nongenital source were excluded from analysis. Multiple positive samples collected from the same patient were pooled into a single sample.HSV was isolated from 764 different patients. HSV1 was isolated in 62.6% of patients (male, 55%; female, 63.8%). HSV1 was isolated in 73.2% of patients 10 to 39 years of age and in 32% of patients ≥40 years of age. The difference in rates of HSV1 infection between the 10 to 39 years of age group and the ≥40 years of age group was statistically significant (P0.001 [χIn New Brunswick, HSV1 is the dominant type of HSV isolated in samples collected from a genital site. Significant rate differences were demonstrated between the groups 10 to 39 years of age and ≥40 years of age.On ne sait pas grand-chose du rôle du virus de l’herpès simplex de type 1 (VHS1) dans l’épidémiologie de l’herpès génital au Canada. Les chercheurs ont analysé les données des cultures d’herpès viral obtenues pendant deux années consécutives à L’Hôpital Dr-Georges-L.-Dumont, où toutes les cultures virales sont effectuées au Nouveau-Brunswick. Ils ont postulé que le VHS1 était la principale cause d’herpès génital dans la province.Les chercheurs ont analysé les prélèvements génitaux envoyés en laboratoire entre juillet 2006 et juin 2008, en vue de cultures du virus d’herpès simplex (VHS). Ils ont exclu de l’analyse les prélèvements tirés d’une source non précisée ou d’origine non génitale. Ils ont regroupé dans un seul échantillon les multiples échantillons positifs prélevés chez le même patient.Le VHS a été isolé chez 764 patients, et le VHS1, chez 62,6 % des patients (55 % chez les hommes, et 63,8 % chez les femmes), soit 73,2 % des patients de dix à 39 ans et 32 % des patients de 40 ans et plus. La différence de taux d’infection par le VHS1 entre le groupe des dix à 39 ans et celui des 40 ans et plus était statistiquement significative (χAu Nouveau-Brunswick, le VHS1 est le principal type de VHS isolé dans des échantillons d’origine génitale. On a établi des différences de taux significatives entre le groupe des dix à 39 ans et celui des 40 ans et plus.

Pseudomonas putida DSM 84 produces N-carbamyl-D-amino acids from the corresponding D-5-monosubstituted hydantoins. The gene encoding this D-hydantoinase enzyme was cloned and expressed in Escherichia coli. The nucleotide sequence of the 1.8-kb insert of subclone pGES19 was determined. One open reading frame of 1,104 bp was found and was predicted to encode a polypeptide with a molecular size of 40.5 kDa. Local regions of identity between the predicted amino acid sequence and that of other known amidohydrolases (two other D-hydantoinases, allantionase and dihydroorotase) were found. The D-hydantoinase gene was used as a probe to screen DNA isolated from diverse organisms. Within Pseudomonas strains of rRNA group I, the probe was specific. The probe did not detect D-hydantoinase genes in pseudomonads not in rRNA group I, other bacteria, or plants known to express D-hydantoinase activity.

A 180 ml grinding vessel, made of Nylatron® GS Nylon adapted to a commercial mixer mill, is described for the laboratory-scale disruption of microorganisms. The new design is inert and is 1.6 times lighter than the previously aluminum 180 ml mortar, which did not permit enzyme and protein releases similar to that observed when commercial 12.5 ml stainless steel mortars were used. With this improvement, maximum enzyme and protein releases observed within 10 and 20 min, respectively, were similar to what was achieved with a commercial 12.5 ml stainless steel mortar.

The ions corresponding to metastable formyl loss from ionized ethylene glycol and 2-methoxyethanol are the conjugate acids of methanol and dimethyl ether, respectively. The structures of the fragments of deuterated analogues reveal that a hydroxylic hydrogen transfers to carbon to create the new methyl group, while a hydrogen originally attached to carbon migrates to oxygen in the course of this double hydrogen transfer. This is the only metastable decomposition of ethylene glycol radical cation, while 2-methoxyethanol radical cation also loses water to form oxetane radical cation

The tert -butyl cation ( t Bu + ) is widely used as a chemical ionization reagent ion, for which it is often assumed that simple proton transfer to neutral substrates is the dominant reaction. Mass-analyzed ion kinetic energy (MIKE) spectrometry and the collisionally activated decomposition (CAD) of ions corresponding to the adducts R′O(H)R + formed from mixtures of ROH and R′OH (R = t Bu, R′ = t Bu or 1-methylcyclopentyl, and their deuterated analogues) show a much more complicated pattern of reactivity, which is mirrored in the bimolecular reactions of t Bu + with R′OH in the Fourier transform ion cyclotron resonance (FT-ICR) technique. Production of R′ + in the CAD and FT-ICR experiments is accompanied by isotopic exchange between the alkyl groups, which implicates ion-neutral complexes as accessible intermediates in addition to the covalent adduct ions. A unified pathway for MIKE spectrometry, CAD, and FT-ICR regimes is presented, involving terbody complexes of the form [cation water alkene] as well as two-body complexes of the form [cation alcohol].

A 180-ml grinding vessel was adapted to a commercially available mixer mill used for small-scale cell disruption by grinding with glass beads and was compared to the currenly used 12.5 ml mortar. The disruption of the following microorganismswas monitored by estimating the protein content of the cell extract and the release of intracellular enzymes: β-galactosidase from Bifidobacterium infantis strain ATCC 27920, hydantoinase from Pseudomonas putida strain DSM 84 and maltase from commercial baker's yeast Saccharomyces cerevisiae strain Bud. Maximun enzyme release occurred within 2.5–10 min and maximum protein release by 10–30 min depending on the organism used. The 180-ml jar is proposed as an alternative to other expensive equipments used for continuous large-scale disruption.

The ions corresponding to metastable formyl loss from ionized ethylene glycol and 2-methoxyethanol are the conjugate acids of methanol and dimethyl ether, respectively. The structures of the fragments of deuterated analogues reveal that a hydroxylic hydrogen transfers to carbon to create the new methyl group, while a hydrogen originally attached to carbon migrates to oxygen in the course of this double hydrogen transfer. This is the only metastable decomposition of ethylene glycol radical cation, while 2-methoxyethanol radical cation also loses water to form oxetane radical cation

Propene radical cations undergo proton transfer reactions with water and methanol at low pressure (Fourier transform ion cyclotron resonance), whereas cyclopropane radical cations react with methanol by addition—fragmentation and with water by collision-induced isomerization to form propene. The isomerization of cyclopropane into propene is slower than the hydrogen exchange between propene and water, making the reaction between C 3 H + 6 and H 2 O a sensitive probe for the structure of the hydrocarbon ion. The structural distinction between the two C 3 H + 6 isomers can also be based on the reactions with methanol.

Although uncommon in North America, Hepatitis E virus (HEV) has been identified in some industrialized countries in patients without a history of travel to HEV-endemic countries. Its presence is ubiquitous worldwide in swine populations. Zoonotic transmission of swine HEV to non human primates has been achieved experimentally and transmission of HEV after ingestion of contaminated raw or undercooked meat is well documented. In Canada, so far, no HEV outbreak has been documented but HEV genotype 3 strains have been identified in sera and faecal samples of swine origin. The objective of the present study was to determine the viral load of HEV in liver, loin, bladder, hepatic lymph node, bile, tonsil, plasma and faeces samples of 43 pigs at slaughter. Feline calicivirus (FCV) was used as sample process control to validate the RNA extraction process, as a confirmation of the absence of sample inhibitors and as an amplification control. Using FCV/HEV multiplex TaqMan RT-qPCR system, HEV RNA was detected in 14 out of the 43 animals tested. HEV was detected in lymph nodes (11/43), bladder (10/43), liver (9/43), bile (8/43), faeces (6/43), tonsils (3/43), plasma (1/43) samples from infected animals. No HEV-positive loin samples were observed. Viral loads of 10(3) to 10(7) copies/g were estimated in positive liver and bile samples.