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1.
J Appl Microbiol ; 128(4): 1119-1127, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31793115

ABSTRACT

AIMS: Pseudomonas spp. have been widely studied for their plant growth-promoting effects. However, their capacity to promote lipid accumulation in oilseed crops is not well characterized. In this study, we evaluated the effect of Pseudomonas fluorescens LBUM677 on lipid accumulation in three oilseed crops: soybean (Glycine max), canola (Brassica napus) and corn gromwell (Buglossoides arvensis), a plant of high nutraceutical interest for its accumulation of the omega-3 stearidonic acid. METHODS AND RESULTS: Pot experiments were conducted under controlled conditions where seeds were inoculated or not with LBUM677 and plants were harvested at 4, 8 and 12 weeks. A qPCR assay specifically targeting LBUM677 was used in parallel to correlate LBUM677 soil rhizosphere competency to growth promotion and seed lipid accumulation. Total oil seed content and fatty acid composition were analysed at seed maturity. Results showed that LBUM677 was able to establish itself in the rhizosphere of the three plant species at similar levels, but it differentially increased plant biomass, total oil content and lipid composition in a plant-specific manner. CONCLUSIONS: Despite some species-specific differences observed in P. fluorescens LBUM677's effect on different crops, the strain appears to be a generalist plant growth-promoting rhizobacteria of oilseed crops. SIGNIFICANCE AND IMPACT OF THE STUDY: LBUM677 shows great potential to be used as an inoculum to promote oil yield and fatty acid accumulation in oilseed crops.


Subject(s)
Biomass , Crops, Agricultural/microbiology , Lipids/chemistry , Pseudomonas fluorescens/physiology , Crops, Agricultural/chemistry , Crops, Agricultural/classification , Crops, Agricultural/growth & development , Fatty Acids/analysis , Fatty Acids/chemistry , Plant Oils/chemistry , Pseudomonas fluorescens/growth & development , Rhizosphere , Seeds/chemistry , Seeds/classification , Seeds/growth & development , Seeds/microbiology , Soil Microbiology , Species Specificity
2.
J Appl Microbiol ; 127(1): 208-218, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30985950

ABSTRACT

AIMS: The aim of this study was to evaluate the persistence of Pseudomonas fluorescens LBUM677 in the rhizosphere of Buglossoides arvensis under agricultural field conditions and determine if B. arvensis intraspecific genetic variations affect the capacity of LBUM677 to colonize its rhizosphere and increase seed oil and stearidonic acid (SDA) accumulation. METHODS AND RESULTS: Two field experiments were performed to: (i) study the persistence of various concentrations of LBUM677 inoculated in the rhizosphere of B. arvensis and determine a minimum inoculation threshold required to maximize biological activity; and (ii) study the impact of B. arvensis intraspecific genetic variations on LBUM677 rhizosphere colonization and seed oil and SDA accumulation. In order to track LBUM677 populations in soil over time, a specific quantitative polymerase chain reaction assay was developed. Inoculation with a minimum of 109 LBUM677 bacterial cells per plant was determined as a threshold to promote maximum B. arvensis rhizosphere colonization and seed oil and SDA accumulation. Buglossoides arvensis intraspecific genetic variations had an impact on rhizosphere colonization, B. arvensis seed oil and SDA accumulation, where two cultivars benefited more than others from LBUM677 inoculation. CONCLUSIONS: LBUM677 can colonize the rhizosphere and increase seed oil and SDA yields in B. arvensis plants in a cultivar-dependant manner. SIGNIFICANCE AND IMPACT OF THE STUDY: LBUM677 shows potential to be used as a biofertilizer to specifically increase seed oil and SDA yields in B. arvensis. This will in turn promote the development of an economically viable agricultural-based approach as an alternative for producing high-quality polyunsaturated fatty acids.


Subject(s)
Boraginaceae/microbiology , Fatty Acids, Omega-3/metabolism , Plant Oils/metabolism , Pseudomonas fluorescens/growth & development , Rhizosphere , Soil Microbiology , Boraginaceae/genetics , Boraginaceae/metabolism , Genetic Variation , Plant Roots/microbiology , Seeds/metabolism , Seeds/microbiology
3.
J Appl Microbiol ; 125(1): 203-215, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29495107

ABSTRACT

AIM: This study was performed to identify bacterial isolates capable of enhancing total lipid and stearidonic acid (SDA) yields in Buglossoides arvensis. METHODS AND RESULTS: Pot experiments were conducted to screen the effects of 40 bacterial isolates on different B. arvensis growth parameters. Five isolates increased total lipid and SDA yields by at least 20%. These isolates were tested in a second pot experiment and in field trials. The second pot experiment confirmed that all isolates significantly increased total lipid and SDA yields over controls. Plants inoculated with four bacterial strains experienced significantly higher shoot weights, however, the increase in shoot weight decreased over time. Three isolates led to higher total seed numbers. In field trials, the inoculations had no significant effect on seed or lipid yields. However, isolate Pseudomonas fluorescens LBUM677 significantly increased SDA yield by 33% as compared to control plants. This strain was also the most efficient biofilm producer. CONCLUSIONS: Pseudomonas fluorescens LBUM677 can significantly increase SDA yield in B. arvensis under controlled and field conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: Using bacterial strains to increase plant yield is of great interest under commercial settings. Pseudomonas fluorescens LBUM677 shows promise to promote SDA accumulation in B. arvensis under production conditions.


Subject(s)
Boraginaceae , Fatty Acids, Omega-3 , Pseudomonas fluorescens/physiology , Boraginaceae/metabolism , Boraginaceae/microbiology , Fatty Acids, Omega-3/analysis , Fatty Acids, Omega-3/metabolism , Lipid Metabolism/physiology , Lipids/analysis , Seeds/metabolism
4.
Climacteric ; 17(3): 294-300, 2014 Jun.
Article in English | MEDLINE | ID: mdl-23931598

ABSTRACT

OBJECTIVE: The purpose of the present study was to examine the relationship between two different levels of protein intake (0.8 vs.1.2 g/kg body weight/day) with muscle mass and muscle strength. METHOD: Seventy-two postmenopausal women were recruited. Body composition (bioelectrical impedance analysis), muscle strength (dynamometer), energy metabolism (indirect calorimetry) and dietary intake (dietary journal) were measured. We divided the women into two groups. Women with a protein intake of ≥ 1.2 g/kg body weight/day were placed in the Protein ≥ 1.2 group (n = 35), whereas women with a protein intake of 0.8-1.19 g/kg body weight/day were categorized in the Protein 0.8-1.19 group (n = 32). RESULTS: No significant difference was observed between groups for age, height, skeletal muscle mass, resting energy expenditure, total energy expenditure, carbohydrate and lipid intake. Significant differences between groups were observed for body mass index (p < 0.001), fat mass (p < 0.001) and muscle strength (hand grip and knee extensors) (p < 0.001). More specifically, the Protein ≥ 1.2 group presented a higher muscle strength as well as a lower body mass index and fat mass compared to the Protein 0.8-1.19 group. In addition, the group with a protein intake of ≥ 1.2 g/kg body weight/day presented significantly higher energy intake (p = 0.002), and essential (p < 0.001) and non-essential (p < 0.001) amino acid intake. Interestingly, when muscle strength was adjusted for essential or non-essential amino acids, differences in muscle strength persisted. CONCLUSION: The present study indicates higher levels of muscle strength in postmenopausal women with a protein intake of ≥ 1.2 g/kg body weight/day compared to 0.8-1.19 g/kg body weight/day despite no differences in muscle mass.


Subject(s)
Dietary Proteins/administration & dosage , Hand Strength/physiology , Muscle, Skeletal/anatomy & histology , Postmenopause/physiology , Adiposity , Aged , Amino Acids, Essential , Body Mass Index , Energy Intake/physiology , Energy Metabolism/physiology , Female , Humans , Middle Aged , Organ Size
5.
Implement Sci ; 8: 55, 2013 May 22.
Article in English | MEDLINE | ID: mdl-23692634

ABSTRACT

BACKGROUND: The clinical pathway is a tool that operationalizes best evidence recommendations and clinical practice guidelines in an accessible format for 'point of care' management by multidisciplinary health teams in hospital settings. While high-quality, expert-developed clinical pathways have many potential benefits, their impact has been limited by variable implementation strategies and suboptimal research designs. Best strategies for implementing pathways into hospital settings remain unknown. This study will seek to develop and comprehensively evaluate best strategies for effective local implementation of externally developed expert clinical pathways. DESIGN/METHODS: We will develop a theory-based and knowledge user-informed intervention strategy to implement two pediatric clinical pathways: asthma and gastroenteritis. Using a balanced incomplete block design, we will randomize 16 community emergency departments to receive the intervention for one clinical pathway and serve as control for the alternate clinical pathway, thus conducting two cluster randomized controlled trials to evaluate this implementation intervention. A minimization procedure will be used to randomize sites. Intervention sites will receive a tailored strategy to support full clinical pathway implementation. We will evaluate implementation strategy effectiveness through measurement of relevant process and clinical outcomes. The primary process outcome will be the presence of an appropriately completed clinical pathway on the chart for relevant patients. Primary clinical outcomes for each clinical pathway include the following: Asthma--the proportion of asthmatic patients treated appropriately with corticosteroids in the emergency department and at discharge; and Gastroenteritis--the proportion of relevant patients appropriately treated with oral rehydration therapy. Data sources include chart audits, administrative databases, environmental scans, and qualitative interviews. We will also conduct an overall process evaluation to assess the implementation strategy and an economic analysis to evaluate implementation costs and benefits. DISCUSSION: This study will contribute to the body of evidence supporting effective strategies for clinical pathway implementation, and ultimately reducing the research to practice gaps by operationalizing best evidence care recommendations through effective use of clinical pathways. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01815710.


Subject(s)
Asthma/therapy , Critical Pathways/organization & administration , Emergency Service, Hospital/organization & administration , Gastroenteritis/therapy , Asthma/economics , Child , Cluster Analysis , Costs and Cost Analysis , Critical Pathways/economics , Diffusion of Innovation , Emergency Service, Hospital/economics , Gastroenteritis/economics , Hospitalization/economics , Hospitalization/statistics & numerical data , Hospitals, Community , Humans , Medical Audit , Ontario , Outcome and Process Assessment, Health Care , Program Evaluation , Sample Size , Treatment Outcome , Triage
6.
J Nutr Health Aging ; 16(7): 616-9, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22836702

ABSTRACT

OBJECTIVE: The purpose of this study was to investigate the relationship between protein intake and dynapenia. DESIGN: A cross-sectional/observational study. SETTING: Department of Kinanthropology at the University of Quebec at Montreal. PARTICIPANTS: Seventy-two non-frail postmenopausal women aged between 50 to 75 years were recruited. MEASUREMENTS: Body weight (BW), lean body mass (LBM; %) and skeletal muscle mass (bio-electrical impedancemetry analysis), maximum voluntary handgrip strength (using hand dynamometer), aerobic capacity (VO2peak) and dietary intake were measured. Women were divided according to dynapenia criteria. RESULTS: The strongest correlation between muscle strength and protein intake was observed when we express the amount of protein in g/d/BW. No differences for age, BMI, status of menopause, fat mass and VO2peak were observed between non-dynapenic, type I dynapenic and type II dynapenic women, independently of the criteria used. We observed significant differences in protein intake (g/d/BW) between non-dynapenic and type II dynapenic (p<0.01) as well as between type I dynapenic and type II dynapenic (p<0.01) when dynapenia was expressed in kg/BW and in kg/LBM, respectively. It should be noted that no differences in LBM between the three groups were observed when dynapenia was expressed in kg/BW and kg/LBM. Protein intake for all groups respected the RDA of 0.8 to 1.2 g/d/BW (non-dynapenic: 1.44/1.38; type I dynapenic: 1.30/1.33; type II dynapenic: 1.05/1.08 g/d/BW). CONCLUSIONS: Protein intake seems to play a role in the development of dynapenia particularly at the level of type II dynapenia. Therefore, an increase in the recommended daily allowance for protein intake may be warranted.


Subject(s)
Dietary Proteins/administration & dosage , Muscle Strength/physiology , Postmenopause/physiology , Aged , Body Composition/physiology , Body Mass Index , Body Weight , Cross-Sectional Studies , Female , Hand Strength , Humans , Middle Aged , Muscle, Skeletal/physiology , Nutrition Policy , Quebec
7.
Appl Environ Microbiol ; 77(17): 6249-52, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21724880

ABSTRACT

In this study, we evaluated the effect of soil clay content on RNA isolation and on quantitative reverse transcription-PCR (qRT-PCR) quantification of microbial gene transcripts. The amount of clay significantly altered RNA isolation yields and qRT-PCR analyses. Recommendations are made for quantifying microbial gene transcripts in soil samples varying in clay content.


Subject(s)
Aluminum Silicates/analysis , RNA, Messenger/analysis , RNA, Messenger/isolation & purification , Real-Time Polymerase Chain Reaction/methods , Soil Microbiology , Soil/chemistry , Clay
8.
J Appl Microbiol ; 108(2): 571-81, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19645764

ABSTRACT

AIM: The ability of Clostridium perfringens to survive for a long time in the environment makes it a suitable indicator of faecal pollution, but its use as a routine indicator organism in biosolids and composted biosolids has not yet been adopted. This study was performed to improve our understanding of C. perfringens persistence in composted biosolids by monitoring its presence and studying its genetic diversity. METHODS AND RESULTS: A culture-independent TaqMan qPCR assay targeting the cpn60 gene was adapted to enumerate C. perfringens in composted biosolid samples varying in age from 1 to 24 months. The pathogen was detected in all compost samples under study, but no correlation between composting time and number of cpn60 copies was observed. Rep-PCR detected 14 different C. perfringens genotypes, all belonging to toxinotype A, which is the most common biotype found in human and animal gastrointestinal tracts. CONCLUSIONS: Composting did not significantly decrease the number of C. perfringens cells. High genetic diversity of C. perfringens isolates present in composted biosolids is reported for the first time. SIGNIFICANCE AND IMPACT OF STUDY: This study evaluated tools for surveillance of composting processes, source tracking and risk assessment of composted biosolids.


Subject(s)
Clostridium perfringens/genetics , Clostridium perfringens/isolation & purification , Sewage/microbiology , Soil Microbiology , Cluster Analysis , DNA, Bacterial/isolation & purification , Genes, Bacterial , Genetic Variation , Genotype , Phylogeny , Polymerase Chain Reaction/methods , Refuse Disposal , Sequence Analysis, DNA , Soil/analysis , Time Factors
9.
Water Sci Technol ; 57(4): 471-7, 2008.
Article in English | MEDLINE | ID: mdl-18359983

ABSTRACT

Disposal of human biosolids is a source of concern for public health and the environment. Composting appears to be an interesting alternative to traditional disposal methods as it can decrease the load of human pathogenic microorganisms often present in biosolids and yield an end-product rich in nutrients for use as a soil supplement. Assessing the exact microbial content of biosolids, both for biosafety and operational reasons, has traditionally relied on the use of standard microbiological methods. Recent developments in molecular-based technologies now offer more rapid and specific monitoring of microorganisms in biosolids than culture-based methods. In this study, denaturing gradient gel electrophoresis (DGGE) was adapted to monitor the succession of bacteria in composted biosolids through different steps of compost production. Secondly, a TaqMan quantitative real time PCR (qPCR) approach was developed to detect and quantify the presence of Salmonella species, a model human pathogenic bacterium, susceptible to be found in biosolids. DGGE results indicated that the bacterial content of composted biosolids of different ages belongs to various taxa and significantly changes with age. qPCR results indicated that the quantity of Salmonella species found in composted biosolids ranging from 1 to 24 months significantly decreases with composting time.


Subject(s)
Environmental Microbiology , Salmonella/isolation & purification , Sewage/microbiology , Soil , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Electrophoresis, Polyacrylamide Gel/methods , Humans , Polymerase Chain Reaction/methods , Salmonella/genetics , Waste Disposal, Fluid/methods
10.
J Microbiol Methods ; 60(2): 143-54, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15590089

ABSTRACT

In North America, asparagus (Asparagus officinalis) production suffers from a crown and root rot disease mainly caused by Fusarium oxysporum f. sp. asparagi and F. proliferatum. Many other Fusarium species are also found in asparagus fields, whereas accurate detection and identification of these organisms, especially when processing numerous samples, is usually difficult and time consuming. In this study, a PCR-denaturing gradient gel electrophoresis (DGGE) method was developed to assess Fusarium species diversity in asparagus plant samples. Fusarium-specific PCR primers targeting a partial region of the translation elongation factor-1 alpha (EF-1 alpha) gene were designed, and their specificity was tested against genomic DNA extracted from a large collection of closely and distantly related organisms isolated from multiple environments. Amplicons of 450 bp were obtained from all Fusarium isolates, while no PCR product was obtained from non-Fusarium organisms. The ability of DGGE to discriminate between Fusarium taxa was tested over 19 different Fusarium species represented by 39 isolates, including most species previously reported from asparagus fields worldwide. The technique was effective to visually discriminate between the majority of Fusarium species and/or isolates tested in pure culture, while a further sequencing step permitted to distinguish between the few species showing similar migration patterns. Total genomic DNA was extracted from field-grown asparagus plants naturally infested with different Fusarium species, submitted to PCR amplification, DGGE analysis and sequencing. The two to four bands observed for each plant sample were all affiliated with F. oxysporum, F. proliferatum or F. solani, clearly supporting the reliability, sensitivity and specificity of this approach for the study of Fusarium diversity from asparagus plants samples.


Subject(s)
Asparagus Plant/microbiology , Fusarium/genetics , Plant Diseases/microbiology , Base Sequence , DNA, Fungal/chemistry , DNA, Fungal/genetics , Electrophoresis, Polyacrylamide Gel , Genetic Variation , Molecular Sequence Data , Peptide Elongation Factor 1/chemistry , Peptide Elongation Factor 1/genetics , Phylogeny , Polymerase Chain Reaction , Sequence Analysis, DNA
11.
Appl Environ Microbiol ; 70(6): 3541-51, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15184155

ABSTRACT

Bacterial and fungal populations associated with the rhizosphere of healthy black spruce (Picea mariana) seedlings and seedlings with symptoms of root rot were characterized by cloned rRNA gene sequence analysis. Triplicate bacterial and fungal rRNA gene libraries were constructed, and 600 clones were analyzed by amplified ribosomal DNA restriction analysis and grouped into operational taxonomical units (OTUs). A total of 84 different bacterial and 31 different fungal OTUs were obtained and sequenced. Phylogenetic analyses indicated that the different OTUs belonged to a wide range of bacterial and fungal taxa. For both groups, pairwise comparisons revealed that there was greater similarity between replicate libraries from each treatment than between libraries from different treatments. Significant differences between pooled triplicate samples from libraries of genes from healthy seedlings and pooled triplicate samples from libraries of genes from diseased seedlings were also obtained for both bacteria and fungi, clearly indicating that the rhizosphere-associated bacterial and fungal communities of healthy and diseased P. mariana seedlings were different. The communities associated with healthy and diseased seedlings also showed distinct ecological parameters as indicated by the calculated diversity, dominance, and evenness indices. Among the main differences observed at the community level, there was a higher proportion of Acidobacteria, Gammaproteobacteria, and Homobasidiomycetes clones associated with healthy seedlings, while the diseased-seedling rhizosphere harbored a higher proportion of Actinobacteria, Sordariomycetes, and environmental clones. The methodological approach described in this study appears promising for targeting potential rhizosphere-competent biological control agents against root rot diseases occurring in conifer nurseries.


Subject(s)
Bacteria/classification , Fungi/classification , Picea/microbiology , Plant Diseases/microbiology , Plant Roots/microbiology , Soil Microbiology , Bacteria/genetics , Bacteria/isolation & purification , Ecosystem , Fungi/genetics , Fungi/isolation & purification , Genes, rRNA , Molecular Sequence Data , Phylogeny , Restriction Mapping , Seedlings/growth & development , Sequence Analysis, DNA
12.
Phytopathology ; 93(2): 229-35, 2003 Feb.
Article in English | MEDLINE | ID: mdl-18943138

ABSTRACT

ABSTRACT The capacity of the arbuscular mycorrhizal fungus Glomus intraradices in reducing the presence of Fusarium solani f. sp. phaseoli in bean plants and the surrounding mycorrhizosphere soil was evaluated in a compartmentalized experimental system. Quantification of the pathogen and the symbiont in plant tissues, the soil regions of the mycorrhizosphere (rhizosphere and mycosphere), and the bulk soil was accomplished using specific polymerase chain reaction (PCR) primers in real-time PCR assays, culture-dependant methods, and microscopic determination techniques. Nonmycorrhizal bean plants infected with the pathogen had distinctive Fusarium root rot symptoms, while infected plants previously colonized by G. intraradices remained healthy. The amount of F. solani f. sp. phaseoli genomic DNA was significantly reduced in mycorrhizal bean plants and in each mycorrhizosphere soil compartment. The presence of G. intraradices in the mycorrhizosphere was not significantly modified, although the mycorrhizal colonization of roots was slightly increased in the presence of the pathogen. The results suggest that the reduced presence of Fusarium as well as root rot symptoms are caused by biotic and/or abiotic modifications of the mycorrhizosphere as a result of colonization with G. intraradices.

13.
Prostate ; 49(3): 155-65, 2001 Nov 01.
Article in English | MEDLINE | ID: mdl-11746260

ABSTRACT

BACKGROUND: We have isolated a mycobacterial cell wall-DNA complex (MCC) possessing anti-cancer activity against bladder cancer cells. The anti-cancer activity of MCC appears to be due to two effects: a direct interaction with bladder cancer cells resulting in the induction of apoptosis and an indirect effect via the stimulation of monocytes and macrophages cytokine synthesis. In this study, the direct effect of MCC towards LNCaP cancer cells was evaluated. METHODS: Inhibition of proliferation, cell cycle arrest and induction of apoptosis were evaluated in vitro using LNCaP cells treated with MCC. The synthesis of IL-12, GM-CSF, and TNF-alpha by LNCaP cells in response to MCC was also determined. Experiments were performed to gain insight into the mechanism of action of MCC towards LNCaP cells. RESULTS: MCC caused a dose-dependent inhibition of the proliferation of LNCaP cells that was associated with cell cycle arrest at the G0/G1 phase. MCC-induced apoptosis of LNCaP cells was consistent with a mitochondrial pathway involving mitochondrial disruption, release of cytochrome c, and an increase in Bax protein levels leading to caspase-3 and -7 activation and cleavage of poly (ADP-ribose) polymerase and nuclear mitotic apparatus protein. Surprisingly, MCC also directly induced the synthesis of IL-12 and GM-CSF, but not TNF-alpha, by LNCaP cells. CONCLUSIONS: MCC possesses the ability to directly induce apoptosis of LNCaP cells and to trigger the synthesis of IL-12 and GM-CSF by these cells, suggesting a potential role of MCC for the treatment of prostate cancer.


Subject(s)
DNA, Bacterial/pharmacology , Mycobacterium phlei/chemistry , Prostatic Neoplasms/pathology , Apoptosis/drug effects , Blotting, Western , Caspase 3 , Caspases/analysis , Caspases/biosynthesis , Caspases/metabolism , Cell Cycle/drug effects , Cell Division/drug effects , Cell Wall/chemistry , Cytokines/analysis , Cytokines/biosynthesis , DNA Fragmentation/drug effects , Enzyme-Linked Immunosorbent Assay , Flow Cytometry , Humans , Male , Membrane Potentials/drug effects , Microscopy, Fluorescence , Mitochondria/drug effects , Mitochondria/physiology , Poly(ADP-ribose) Polymerases/analysis , Poly(ADP-ribose) Polymerases/biosynthesis , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/immunology , Tumor Cells, Cultured
14.
J Pharm Pharmacol ; 53(4): 555-61, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11341374

ABSTRACT

Hyaluronic acid (HA), an abundant non-sulfated glycosaminoglycan component of the extracellular matrix, has applications in drug delivery, tissue engineering and as an ingredient in cosmetics. HA preparations containing high-molecular-weight polymers are also used in the treatment of inflammatory disorders such as arthritis and interstitial cystitis. Low-molecular-weight fragments derived from HA have been reported to induce pro-inflammatory cytokines such as IL-12 and TNF-alpha, and could therefore potentially exacerbate existing inflammation. We therefore examined the pro-inflammatory activity of HA preparations, since inflammatory reactions are known to occur following administration of HA. We tested low-molecular-weight fragments obtained from seven different HA preparations, either by sonication (approximately equals 3 x 10(5) Da) or by hyaluronidase digestion (approximately equals 1 x 10(4) Da), for the ability to induce the synthesis of IL-12 and TNF-alpha by human monocytic cells. We found that two of the seven HA preparations tested stimulated the synthesis of IL-12 and TNF-alpha by human monocytic cells. We unexpectedly found that the induction of IL-12 and TNF-alpha by these HA preparations was not due to their degradation to low-molecular-weight fragments, since their native high-molecular-weight forms possessed the same ability to stimulate IL-12 and TNF-alpha synthesis, but was due to the presence of contaminating DNA. Treatment of these two HA preparations with deoxyribonuclease I abrogated or reduced the induction of IL-12 and TNF-alpha. It is clear from this study that HA preparations can induce the synthesis of pro-inflammatory cytokines by monocytes. The ability of HA to act as a pro-inflammatory mediator may not, however, be related to the presence of low-molecular-weight HA fragments, but to the presence of DNA. The presence of pro-inflammatory DNA in HA preparations should be evaluated before its use, not only for the treatment of patients with inflammatory disorders, but also before many other applications.


Subject(s)
Adjuvants, Immunologic/adverse effects , DNA , Drug Contamination , Hyaluronic Acid/adverse effects , Inflammation/chemically induced , Arthritis/drug therapy , Cell Culture Techniques , Cystitis, Interstitial/drug therapy , Electrophoresis, Agar Gel , Humans , Hyaluronic Acid/immunology , Interleukin-12/biosynthesis , Molecular Weight , Monocytes/immunology , Tumor Necrosis Factor-alpha/biosynthesis
15.
Expert Opin Investig Drugs ; 10(12): 2157-65, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11772311

ABSTRACT

Cell wall skeletons isolated from many bacteria have been shown to possess anticancer activity. The anticancer activities of such preparations have been attributed to the activation of immune effector cells and not to a direct effect on cancer cell division. A cell wall extract from Mycobacterium phlei, wherein mycobacterial DNA in the form of short oligonulceotides is preserved to the cell wall, has anticancer activity against a wide range of cancer cells. Mycobacterial cell wall-DNA complexes (MCC) exert their anticancer activity by a dual mechanism of action: an indirect effect via the induction of anticancer cytokines and a direct effect on cancer cell division mediated by the induction of apoptosis. In this review, the immunomodulatory and the pro-apoptotic mechanisms of action of MCC will be explored. The identification of the active component in MCC will be discussed, as well as the composition differences with cell wall skeletons and live mycobacteria. Finally, the use of MCC against bladder and prostate cancers will be discussed and compared to standard therapies, particularly therapy using mycobacteria and mycobacteria-derived products.


Subject(s)
Biological Products/chemistry , Cell Wall/chemistry , DNA, Bacterial/therapeutic use , Mycobacterium/chemistry , Adjuvants, Immunologic/pharmacology , Animals , Apoptosis/drug effects , DNA, Bacterial/chemistry , DNA, Bacterial/pharmacology , Humans , Male , Prostatic Neoplasms/drug therapy , Urinary Bladder Neoplasms/drug therapy
16.
Cancer Immunol Immunother ; 49(6): 325-34, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10946815

ABSTRACT

A mycobacterial cell wall complex prepared from the non-pathogenic microorganism Mycobacterium phlei, where mycobacterial DNA is preserved and complexed to cell wall fragments, possesses anticancer and immunomodulatory activity. DNA from a number of prokaryotes has been found to modulate the immune system and to induce cytokine synthesis. We have therefore determined whether the DNA associated with this complex has the ability to induce the synthesis of interleukin-12 (IL-12), a potent anticancer cytokine. Mycobacterial DNA complexed with cell wall fragments or DNA purified from M. phlei induced IL-12 synthesis by murine and human monocytes and macrophages in vitro, and was capable of inducing IL-12 synthesis in vivo in mice following i.p. administration. Neutralization of DNA with cationic liposomes or digestion with DNase I significantly decreased the ability of the cell wall complex to induce IL-12. CpG methylation of DNA extracted from these cell walls or from M. phlei did not affect the induction of IL-12 synthesis by monocytes and macrophages. In contrast, CpG methylation of DNA from Escherichia coli abolished its ability to induce IL-12 synthesis. These results demonstrate that unmethylated CpG motifs present in M. phlei DNA are not a prerequisite for the induction of IL-12 synthesis. The size of the mycobacterial DNA, in the range of 5 bp to genomic DNA, did not influence its capacity to induce IL-12. Our results emphasize that M. phlei DNA associated with the cell wall complex makes a significant contribution to the overall immunomodulatory and anticancer activity of this mycobacterial cell wall preparation and that these activities are not correlated with the presence of CpG motifs.


Subject(s)
Cell Wall/chemistry , DNA, Bacterial/pharmacology , Dinucleoside Phosphates/physiology , Interleukin-12/biosynthesis , Mycobacterium phlei/physiology , Animals , DNA Methylation , Female , HL-60 Cells , Humans , Lipopolysaccharides/analysis , Liposomes/pharmacology , Macrophages/drug effects , Macrophages/metabolism , Mice , Monocytes/drug effects , Monocytes/metabolism , Mycolic Acids/pharmacology
17.
Ann Neurol ; 47(4 Suppl 1): S35-40; discussion S40-1, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10762130

ABSTRACT

The current functional model of the basal ganglia suggests that dyskinesia results from abnormally low activity at the output of the system. This view appears incomplete. The recent literature suggests other factors. Thus, dyskinesia may result from disturbance of surround inhibition: a physiologic mechanism to select neuronal responses. A major criterion for selection in the basal ganglia is prediction of reward, materialized by release of dopamine. However, much of this release is independent of impulse flow, and controlled presynaptically, at a myriad of terminals, whose presence is then essential. Thus, levodopa in parkinsonism is likely to exaggerate imbalance between regions of the basal ganglia more or less deprived of dopaminergic terminals. The cortex and thalamus may be viewed as equally important afferents to the basal ganglia. Each of them appears to influence preponderantly its own half of striatal projection neurons. Those of the indirect pathway would be part of a mainly transcortical loop, specialized for the precise weighing, and selection of cortical information. Those of the direct pathway would be part of a predominantly subcortical loop, more likely concerned by changes in alertness and attention. Dyskinesia could thus result from imbalance between cortical and thalamic functions, between selection and attention.


Subject(s)
Basal Ganglia/physiopathology , Dopamine Agents/adverse effects , Dyskinesia, Drug-Induced/physiopathology , Levodopa/adverse effects , Parkinson Disease/drug therapy , Basal Ganglia/drug effects , Humans
18.
Can J Occup Ther ; 67(1): 31-41, 2000 Feb.
Article in French | MEDLINE | ID: mdl-10695167

ABSTRACT

The occupational therapist is frequently involved in the allocation process of lifting devices for clients with severe physical disabilities who are living in the community. The aim of this paper is to introduce a conceptual framework to help therapists prescribe lifting devices, including the slings. First, factors influencing the decision to prescribe such an aid are analysed based on the concepts of the Canadian Model of Occupational Performance (Canadian Association of Occupational Therapists, 1997). When working with clients toward maximizing their transfer skills, occupational therapists will take into account different aspects such as the characteristics of the client, the environment and the equipment, as well as the time allocated to complete the activity. Secondly, the notion of the work situation outlined by an organization specializing in work safety measures is used as a guide for transfer evaluation. From this viewpoint, the introduction of the lifting device occurs along a continuum of progressive loss of independence and is determined by degrees of personal independence, human assistance as well as technical assistance required to perform transfers. Finally, advantages and disadvantages of using lifting devices in a home setting are presented as a conclusion to the study.


Subject(s)
Disabled Persons , Occupational Therapy , Self-Help Devices , Equipment Design , Humans , Lifting , Transportation of Patients
19.
Am J Med Genet ; 85(1): 20-30, 1999 Jul 02.
Article in English | MEDLINE | ID: mdl-10377009

ABSTRACT

The activity of cytochrome oxidase (CO), the terminal enzyme of the mitochondrial electron transport chain, has been reported to be lower in the brains of Alzheimer disease (AD) patients. This suggests that a modification of mitochondrial DNA (mtDNA) may be responsible for this decrease of CO activity. Many mtDNA variants were found by different studies at a higher frequency in AD patients, suggesting that mtDNA variants could confer a genetic susceptibility to AD. In this study, we sequenced the entire mitochondrial genome region that encompasses the three CO genes and the 22 mitochondrial tRNA in 69 AD patients and 83 age-matched controls. We detected a total of 95 mtDNA variants. The allele frequencies of the majority of these variants were similar in patients and controls. However, a haplotype composed of three different modifications (positions: 5633, 7476, and 15812) was present in three of the 69 late-onset AD patients (4.3%) and also in 1 of 16 early-onset AD patients (6.2%) but not in control individuals. Given that one of these variants (15812) has already been shown to be associated with another neurodegenerative disease and that all three modifications are relatively conserved and their frequencies in the general population is only 0.1%, our data suggest that the presence of this haplotype may represent a risk factor for AD. We also found a significant association (P < 0.05) of two other variants at positions 709 (rRNA 12S) and 15928 (tRNA(Thr)). These two mtDNA variants are three times more frequent in control individuals compared with AD patients, suggesting that they may be protective against AD.


Subject(s)
Alzheimer Disease/genetics , DNA, Mitochondrial/genetics , Founder Effect , Genome , Phylogeny , Aged , Aged, 80 and over , Alzheimer Disease/ethnology , Base Sequence , Canada , Case-Control Studies , DNA Primers , Female , France/ethnology , Humans , Male , Mutation , Nucleic Acid Conformation , Polymerase Chain Reaction , RNA, Transfer, Ala/chemistry , RNA, Transfer, Ser/chemistry
20.
Br J Cancer ; 79(2): 229-35, 1999 Jan.
Article in English | MEDLINE | ID: mdl-9888462

ABSTRACT

Intact mycobacteria and mycobacterial cell wall extracts have been shown to inhibit the growth of human and murine bladder cancer. Their mechanism of action is, however, poorly understood. Mycobacterium phlei mycobacterial cell complex (MCC) is a cell wall preparation that has mycobacterial DNA in the form of short oligonucleotides complexed on the cell wall surface. In this study, we have investigated the possibility that MCC has anti-cancer activity that is mediated by two different mechanisms--a direct effect on cancer cell proliferation and viability and an indirect effect mediated by the production of interleukin 12 (IL-12), a cytokine known to possess anti-cancer activity. We have found that, although MCC is a potent inducer of IL-12 and IL-6 synthesis in monocytes and macrophages either in vitro or in vivo, it is unable to induce the synthesis of either IL-12, IL-6 or granulocyte-macrophage colony-stimulating factor (GM-CSF) by the human transitional bladder cancer cell lines HT-1197 and HT-1376. MCC is not directly cytotoxic towards these cancer cells, but induces apoptosis as determined by nuclear DNA fragmentation and by the release of nuclear mitotic apparatus protein. Mycobacterium phlei DNA associated with MCC is responsible for the induction of apoptosis. Our results indicate that MCC directly effects bladder cancer cells by inhibiting cellular proliferation through the induction of apoptosis, and has the potential for an indirect anti-cancer activity by stimulating cancer-infiltrating monocytes/macrophages to synthesize IL-12.


Subject(s)
Apoptosis , Bacterial Outer Membrane Proteins/pharmacology , Biological Products/pharmacology , Granulocyte-Macrophage Colony-Stimulating Factor/biosynthesis , Interleukins/biosynthesis , Mycobacterium phlei , Neoplasm Proteins/biosynthesis , Urinary Bladder Neoplasms , Apoptosis/genetics , Cell Division/drug effects , DNA Fragmentation , DNA, Bacterial/pharmacology , DNA, Neoplasm/drug effects , Drug Screening Assays, Antitumor , Humans , Mycobacterium phlei/chemistry , Mycobacterium phlei/genetics , Tumor Cells, Cultured/drug effects , Urinary Bladder Neoplasms/metabolism , Urinary Bladder Neoplasms/pathology , Urinary Bladder Neoplasms/physiopathology
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