Search

Background: Lilium (Lilium longiflorum Thunb.) belongs to the family Liliaceae and is a native of Northern Hemisphere (up to South Canada and Siberia). Conventionally Lilium can easily be propagated by sexual and asexual methods of propagation but these prevalent methods are not capable of meeting the increasing demand in domestic and global market. Generally, Lilium is propagated through bulbs but, limited number of bulbs per plant, long dormancy period of bulbs which again results into non-availability of planting material throughout the year. Keeping in view the above facts, the present study was undertaken with the following objective: "To standardize the cost effective protocol for micro propagation of lilium to produce disease free and true to type plants at a faster rate". Methods: The present investigation was carried out in the Tissue Culture Laboratory of the Centre for Research and Application in Plant Tissue Culture. The experiment was laid out in a C.R.D. (Factorial) with three replications. In vitro raised bulblets were separated out and were transferred on to the root regeneration media. Different levels of NAA were used in MS media for the rooting of in vitro raised bulblets and percent rooting of plantlet is recorded. Result: It was interesting to note that the media LR-3 (MS + NAA 1.0 mg/l) is most efficient for rooting in all type of cultivars. All the three cultivars used responded very poor on media LR-1 (MS basal). [ABSTRACT FROM AUTHOR]

Background: Salmonella enterica serovars are a major cause of foodborne illness and have a substantial impact on global human health. In Canada, Salmonella is commonly found on swine farms and the increasing concern about drug use and antimicrobial resistance associated with Salmonella has promoted research into alternative control methods, including selecting for pig genotypes associated with resistance to Salmonella. The objective of this study was to identify single-nucleotide variants in the pig genome associated with Salmonella susceptibility using a genome-wide association approach. Repeated blood and fecal samples were collected from 809 pigs in 14 groups on farms and tonsils and lymph nodes were collected at slaughter. Sera were analyzed for Salmonella IgG antibodies by ELISA and feces and tissues were cultured for Salmonella. Pig DNA was genotyped using a custom 54 K single-nucleotide variant oligo array and logistic mixed-models used to identify SNVs associated with IgG seropositivity, shedding, and tissue colonization. Results: Variants in/near PTPRJ (p = 0.0000066), ST6GALNAC3 (p = 0.0000099), and DCDC2C (n = 3, p < 0.0000086) were associated with susceptibility to Salmonella, while variants near AKAP12 (n = 3, p < 0.0000358) and in RALGAPA2 (p = 0.0000760) may be associated with susceptibility. Conclusions: Further study of the variants and genes identified may improve our understanding of neutrophil recruitment, intracellular killing of bacteria, and/or susceptibility to Salmonella and may help future efforts to reduce Salmonella on-farm through genetic approaches. [ABSTRACT FROM AUTHOR]

Background: Aquatic bird bornavirus 1 (ABBV-1) has been associated with neurological diseases in wild waterfowls. In Canada, presence of ABBV-1 was demonstrated by RT-qPCR and immunohistochemistry in tissues of waterfowls with history of neurological disease and inflammation of the central and peripheral nervous tissue, although causation has not been proven by pathogenesis experiments, yet. To date, in vitro characterization of ABBV-1 is limited to isolation in primary duck embryo fibroblasts. The objectives of this study were to describe isolation of ABBV-1 in primary duck embryonic fibroblasts (DEF), and characterize replication in DEF and three immortalized avian fibroblast cell lines (duck CCL-141, quail QT-35, chicken DF-1) in order to evaluate cellular permissivity and identify suitable cell lines for routine virus propagation. Methods: The virus was sequenced, and phylogenetic analysis performed on a segment of the N gene coding region. Virus spread in cell cultures, viral RNA and protein production, and titres were evaluated at different passages using immunofluorescence, RT-qPCR, western blotting, and tissue culture dose 50% (TCID50) assay, respectively. Results: The isolated ABBV-1 showed 97 and 99% identity to European ABBV-1 isolate AF-168 and North American ABBV-1 isolates 062-CQ and CG-N1489, and could infect and replicate in DEF, CCL-141, QT-35 and DF-1 cultures. Viral RNA was detected in all four cultures with highest levels observed in DEF and CCL-141, moderate in QT-35, and lowest in DF-1. N protein was detected in western blots from infected DEF, CCL-141 and QT-35 at moderate to high levels, but minimally in infected DF-1. Infectious titre was highest in DEF (between approximately 105 to 106 FFU / 106 cells). Regarding immortalized cell lines, CCL-141 showed the highest titre between approximately 104 to 105 FFU / 106 cells. DF-1 produced minimal infectious titre. Conclusions: This study confirms the presence of ABBV-1 among waterfowl in Canada and reported additional in vitro characterization of this virus in different avian cell lines. ABBV-1 replicated to highest titre in DEF, followed by CCL-141 and QT-35, and poorly in DF-1. Our results showed that CCL-141 can be used instead of DEF for routine ABBV-1 production, if a lower titre is an acceptable trade-off for the simplicity of using immortalized cell line over primary culture. [ABSTRACT FROM AUTHOR]

Legionellosis was diagnosed in an immunocompromised 3-year-old girl in Canada. We traced the source of the bacterium through co-culture with an ameba collected from a hot tub in her home. We identified Legionella pneumophila serogroup 6, sequence type 185, and used whole-genome sequencing to confirm the environmental and clinical isolates were of common origin. [ABSTRACT FROM AUTHOR]

Background Our community-driven projects address concerns of Canadian Arctic Indigenous communities about Helicobacter pylori (Hp) infection, responsible for elevated gastric cancer mortality in the region. A key concern is poor effectiveness of anti- Hp treatment. We aimed to describe antibiotic resistance patterns in Hp isolated from project participants. Methods Participants in 7 communities underwent upper gastrointestinal endoscopy with 2 gastric biopsies taken for tissue culture during 2008-2017. We tested Hp isolates for resistance to 7 antibiotics by Etest and assessed 4 outcomes: resistance to metronidazole, clarithromycin, 1+ antibiotics, and 2+ antibiotics. We tabulated proportion positive among isolates tested with 95% confidence intervals (CI) and used logistic regression to assess the relation of age and sex to resistance outcomes. Results Of 259 Hp isolates tested, resistance to metronidazole, clarithromycin, 1+ antibiotics, and 2+ antibiotics were (% [CI]): respectively, 35 [29-41], 19 [15-25], 44 [38-50], and 12 [8-17] overall; 38 [30-47], 24 [17-32], 49 [41-58], and 16 [11-23] in 146 isolates from women; and 30 [22-39], 13 [8-21], 36 [27-46], and 6 [3-12] in 113 isolates from men. Odds of resistance to clarithromycin, 1+ antibiotics, 2+ antibiotics, and, to a lesser degree metronidazole, were elevated in women relative to men after age adjustment and increased with age in women but not men. Conclusion In Arctic Indigenous communities in Canada, women were more likely than men to harbor antibiotic-resistant Hp, and their frequency of resistant Hp infection increased with age. Key messages Community-driven research answers questions posed by those who bear the disease burden. [ABSTRACT FROM AUTHOR]

We determined the capacity of putative antidiabetic plants used by the Eastern James Bay Cree (Canada) to modulate key enzymes of gluconeogenesis and glycogen synthesis and key regulating kinases. Glucose-6-phosphatase (G6Pase) and glycogen synthase (GS) activities were assessed in cultured hepatocytes treated with crude extracts of seventeen plant species. Phosphorylation of AMP-dependent protein kinase (AMPK), Akt, and Glycogen synthase kinase-3 (GSK-3) were probed by Western blot. Seven of the seventeen plant extracts significantly decreased G6Pase activity, Abies balsamea and Picea glauca, exerting an effect similar to insulin. This action involved both Akt and AMPK phosphorylation. On the other hand, several plant extracts activated GS, Larix laricina and A. balsamea, far exceeding the action of insulin. We also found a significant correlation between GS stimulation and GSK-3 phosphorylation induced by plant extract treatments. In summary, three Cree plants stand out for marked effects on hepatic glucose homeostasis. P. glauca affects glucose production whereas L. laricina rather acts on glucose storage. However, A. balsamea has the most promising profile, simultaneously and powerfully reducing G6Pase and stimulating GS. Our studies thus confirm that the reduction of hepatic glucose production likely contributes to the therapeutic potential of several antidiabetic Cree traditional medicines. [ABSTRACT FROM AUTHOR]

Naphthenic acids, which have a variety of commercial applications, occur naturally in conventional crude oil and in highly biodegraded petroleum such as that found in the Athabasca oil sands in Alberta, Canada. Oil sands extraction is done using a caustic aqueous extraction process. The alkaline pH releases the naphthenic acids from the oil sands and dissolves them into water as their soluble naphthenate forms, which are anionic surfactants. These aqueous extracts contain concentrations of naphthenates that are acutely lethal to fishes and other aquatic organisms. Previous research has shown that naphthenic acids can be taken up by fish, but the distribution of these acids in various tissues of the fish has not been determined. In this study, rainbow trout (Oncorhynchus mykiss) were exposed to commercial (Merichem) naphthenic acids in the laboratory. After a 10-d exposure to approximately 3mg naphthenic acids/L, the fish were dissected and samples of gills, heart, liver, kidney, muscle, and eggs were extracted and analyzed for free (unconjugated) naphthenic acids by a gas chromatography–mass spectrometry method. Each of the tissues contained naphthenic acids and non-parametric statistical analyses showed that gills and livers contained higher concentrations than the muscles and that the livers had higher concentrations than the hearts. Four different species of fish (two fish of each species) were collected from the Athabasca River near two oil sands mining and extraction operations. No free naphthenic acids were detected in the muscle or liver of these fish. [Copyright &y& Elsevier]

Long-term population viability of Fraser River sockeye salmon (Oncorhynchus nerka) is threatened by unusually high levels of mortality as they swim to their spawning areas before they spawn. Functional genomic studies on biopsied gill tissue from tagged wild adults that were tracked through ocean and river environments revealed physiological profiles predictive of successful migration and spawning. We identified a common genomic profile that was correlated with survival in each study. In ocean-tagged fish, a mortality-related genomic signature was associated with a 13.5-fold greater chance of dying en route. In river-tagged fish, the same genomic signature was associated with a 50% increase in mortality before reaching the spawning grounds in one of three stocks tested. At the spawning grounds, the same signature was associated with 3.7-fold greater odds of dying without spawning. Functional analysis raises the possibility that the mortality-related signature reflects a viral infection. [ABSTRACT FROM AUTHOR]

Variations in fish condition, pyloric caeca (PC) mass and tissue metal concentrations were examined in two consecutive summers in yellow perch collected along two polymetallic gradients in Canada, Sudbury (ON) and Rouyn-Noranda (QC). The potential of PC mass variations to help interpret food web-mediated changes in condition was also evaluated. The lack of relationships between PC weight and condition, even in reference lakes, indicated that factors other than feeding rate influenced fish condition. Inter-annual variations in fish condition (12–58%), PC weight (14–20%) and tissue metal concentrations (30–550%) were often of greater magnitude than differences between reference and contaminated fish sampled in the same year. The apparent lack of correspondence between feeding rate and condition and the large inter-annual variation in examined metrics highlight the need to better understand the ecological underpinnings that influence metal toxicity in field situations. [Copyright &y& Elsevier]

Tissue engineering encompasses a multidisciplinary approach geared toward the development of biological substitutes designed to restore and maintain normal function in diseased or injured tissues. This article reviews the basic technology that is used to generate implantable tissue-engineered grafts in vitro that will exhibit characteristics in vivo consistent with the physiology and function of the equivalent healthy tissue. We also examine the current trends in tissue engineering designed to tailor scaffold construction, promote angiogenesis and identify an optimal seeded cell source. Finally, we describe several currently applied therapeutic modalities that use a tissue-engineered construct. While notable progress has clearly been demonstrated in this emerging field, these efforts have not yet translated into widespread clinical applicability. With continued development and innovation, there is optimism that the tremendous potential of this field will be realized. [ABSTRACT FROM AUTHOR]

The author discusses the habitat and cultivation of Cypripedium Arietinum, commonly known as the ram's head lady slipper. The plant is native to the northeastern United States and Canada. The plant is listed as endangered in all the areas in which it is native. The author discusses laboratory propagation of the plant's seeds.

Extensive research has been conducted investigating the effects of ionizing radiation on biological systems, including specific focus at low doses. However, at the surface of the planet, there is the ubiquitous presence of ionizing natural background radiation (NBR) from sources both terrestrial and cosmic. We are currently conducting radiobiological experiments examining the impacts of sub-NBR exposure within SNOLAB. SNOLAB is a deep underground research laboratory in Sudbury, Ontario, Canada located 2 km beneath the surface of the planet. At this depth, significant shielding of NBR components is provided by the rock overburden. Here, we describe a Specialized Tissue Culture Incubator (STCI) that was engineered to significantly reduce background ionizing radiation levels. The STCI was installed 2 km deep underground within SNOLAB. It was designed to allow precise control of experimental variables such as temperature, atmospheric gas composition and humidity. More importantly, the STCI was designed to reduce radiological contaminants present within the underground laboratory. Quantitative measurements validated the STCI is capable of maintaining an appropriate experimental environment for sub-NBR experiments. This included reduction of sub-surface radiological contaminants, most notably radon gas. The STCI presents a truly novel piece of infrastructure enabling future research into the effects of sub-NBR exposure in a highly unique laboratory setting. • Living systems are exposed to natural background radiation at the planet's surface. • The biological significance of ionizing background radiation is not well understood. • A sub-natural background radiation research study is only possible deep underground. • A novel Specialized Tissue Culture Incubator has been designed and engineered. • Instrument commissioning reveals a sub-natural background radiation environment. [ABSTRACT FROM AUTHOR]