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Sample records for bacterial recovery viability

  1. Antimicrobial Photodynamic Therapy: Study of Bacterial Recovery Viability and Potential Development of Resistance after Treatment

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    Eliana Alves

    2010-01-01

    Full Text Available Antimicrobial photodynamic therapy (aPDT has emerged in the clinical field as a potential alternative to antibiotics to treat microbial infections. No cases of microbial viability recovery or any resistance mechanisms against it are yet known. 5,10,15-tris(1-Methylpyridinium-4-yl-20-(pentafluorophenyl-porphyrin triiodide (Tri-Py+-Me-PF was used as photosensitizer. Vibrio fischeri and recombinant Escherichia coli were the studied bacteria. To determine the bacterial recovery after treatment, Tri-Py+-Me-PF (5.0 µM was added to bacterial suspensions and the samples were irradiated with white light (40 W m-2 for 270 minutes. Then, the samples were protected from light, aliquots collected at different intervals and the bioluminescence measured. To assess the development of resistance after treatment, bacterial suspensions were exposed to white light (25 minutes, in presence of 5.0 μM of Tri-Py+-Me-PF (99.99% of inactivation and plated. After the first irradiation period, surviving colonies were collected from the plate and resuspended in PBS. Then, an identical protocol was used and repeated ten times for each bacterium. The results suggest that aPDT using Tri-Py+-Me-PF represents a promising approach to efficiently destroy bacteria since after a single treatment these microorganisms do not recover their viability and after ten generations of partially photosensitized cells neither of the bacteria develop resistance to the photodynamic process.

  2. Optimal optical trap for bacterial viability

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    Mirsaidov, Utkur; Timp, Winston; Timp, Kaethe; Mir, Mustafa; Matsudaira, Paul; Timp, Gregory

    2008-08-01

    Optical trapping is a powerful tool for the micromanipulation of living cells—especially bacteria—but photodamage induced by the laser beam can adversely affect viability. We have explored optical trapping conditions in the near infrared (840-930nm) that preserve the viability of E. coli, as measured by gene expression of green fluorescent protein. We have found that time-sharing the optical traps, i.e., dwelling only 10μs-1ms on the cell, improves viability relative to continuous wave (CW) exposure for the same exposure time. We have also observed that similar to CW traps the photodamage in a time-shared trap depends weakly on wavelength, but linearly on peak power, implying an effect induced by single photon absorption. Taken altogether, integrating the exposure time and peak power, the data indicate that there is a lethal energy dose of about 5J for E. coli. Thus a single parameter—the energy—can be used to describe the limitation on viability.

  3. Viability of Biopolymers for Enhanced Oil Recovery

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    Sveistrup, Marte; van Mastrigt, Frank; Norrman, Jens; Picchioni, Francesco; Paso, Kristofer

    2016-01-01

    Xanthan gum and scleroglucan are assessed as environmentally friendly enhanced oil recovery (EOR) agents. Viscometric and interfacial tension measurements show that the polysaccharides exhibit favorable viscosifying performance, robust shear tolerance, electrolyte tolerance, and moderate

  4. Modelling the viability of heat recovery from combined sewers.

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    Abdel-Aal, M; Smits, R; Mohamed, M; De Gussem, K; Schellart, A; Tait, S

    2014-01-01

    Modelling of wastewater temperatures along a sewer pipe using energy balance equations and assuming steady-state conditions was achieved. Modelling error was calculated, by comparing the predicted temperature drop to measured ones in three combined sewers, and was found to have an overall root mean squared error of 0.37 K. Downstream measured wastewater temperature was plotted against modelled values; their line gradients were found to be within the range of 0.9995-1.0012. The ultimate aim of the modelling is to assess the viability of recovering heat from sewer pipes. This is done by evaluating an appropriate location for a heat exchanger within a sewer network that can recover heat without impacting negatively on the downstream wastewater treatment plant (WWTP). Long sewers may prove to be more viable for heat recovery, as heat lost can be reclaimed before wastewater reaching the WWTP.

  5. Effect of air drying on bacterial viability: A multiparameter viability assessment

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    Nocker, A.; Fernández, P.S.; Montijn, R.; Schuren, F.

    2012-01-01

    The effect of desiccation on the viability of microorganisms is a question of great interest for a variety of public health questions and industrial applications. Although viability is traditionally assessed by plate counts, cultivation-independent methods are increasingly applied with the aim to

  6. Bacterial melanin promotes recovery after sciatic nerve injury in rats

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    Olga V Gevorkyan; Irina B Meliksetyan; Tigran R Petrosyan; Anichka S Hovsepyan

    2015-01-01

    Bacterial melanin, obtained from the mutant strain of Bacillus Thuringiensis, has been shown to promote recovery after central nervous system injury. It is hypothesized, in this study, that bacterial melanin can promote structural and functional recovery after peripheral nerve injury. Rats subjected to sciatic nerve transection were intramuscularly administered bacterial melanin. The sciatic nerve transected rats that did not receive intramuscular administration of bacterial melanin served as...

  7. Effects of low-molecular weight alcohols on bacterial viability

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    Man Adrian

    2017-10-01

    Full Text Available Alcohol based solutions are among the most convenient and wide spread aid in the prevention of nosocomial infections. The current study followed the efficacy of several types and isomers of alcohols on different bacterial species. Seven alcohols (ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert-butyl alcohol, and ethylene glycol were used to evaluate their minimal inhibitory and bactericidal effects by microdilution method on bacteria that express many phenotypical characteristics: different cell-wall structure (Gram positive/negative bacteria, capsule production (Klebsiella pneumoniae, antibiotic resistance (MRSA vs MSSA or high environmental adaptability (Pseudomonas aeruginosa. Results: The best inhibitory effect was noticed for n-propyl, followed by iso-propyl, n-butyl, and iso-butyl alcohols with equal values. Ethylene glycol was the most inefficient alcohol on all bacteria. In K. pneumoniae and P. aeruginosa, the bactericidal concentrations were higher than the inhibitory one, and to a level similar to that encountered for most of the Gram-positive bacteria. Among Gram-positive cocci, E. faecalis presented the lowest susceptibility to alcohols. Conclusions: All alcohols presented good effect on bacteria, even in low concentrations. Compared to ethanol as standard, there are better alternatives that can be used as antimicrobials, namely longer-chain alcohols such as propyl or butyric alcohols and their iso- isomers. Ethylene glycol should be avoided, due to its toxicity hazard and low antimicrobial efficacy. Bacterial phenotype (highly adaptable bacteria, biofilm formation and structure (cell wall structure, presence of capsule may drastically affect the responsiveness to the antimicrobial activity of alcohols, leading to higher bactericidal than inhibitory concentrations.

  8. Maintenance and assessment of cell viability in formulation of non-sporulating bacterial inoculants.

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    Berninger, Teresa; González López, Óscar; Bejarano, Ana; Preininger, Claudia; Sessitsch, Angela

    2018-03-01

    The application of beneficial, plant-associated microorganisms is a sustainable approach to improving crop performance in agriculture. However, microbial inoculants are often susceptible to prolonged periods of storage and deleterious environmental factors, which negatively impact their viability and ultimately limit efficacy in the field. This particularly concerns non-sporulating bacteria. To overcome this challenge, the availability of protective formulations is crucial. Numerous parameters influence the viability of microbial cells, with drying procedures generally being among the most critical ones. Thus, technological advances to attenuate the desiccation stress imposed on living cells are key to successful formulation development. In this review, we discuss the core aspects important to consider when aiming at high cell viability of non-sporulating bacteria to be applied as microbial inoculants in agriculture. We elaborate the suitability of commonly applied drying methods (freeze-drying, vacuum-drying, spray-drying, fluidized bed-drying, air-drying) and potential measures to prevent cell damage from desiccation (externally applied protectants, stress pre-conditioning, triggering of exopolysaccharide secretion, 'helper' strains). Furthermore, we point out methods for assessing bacterial viability, such as colony counting, spectrophotometry, microcalorimetry, flow cytometry and viability qPCR. Choosing appropriate technologies for maintenance of cell viability and evaluation thereof will render formulation development more efficient. This in turn will aid in utilizing the vast potential of promising, plant beneficial bacteria as sustainable alternatives to standard agrochemicals. © 2018 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  9. Temperature fluctuations during deep temperature cryopreservation reduce PBMC recovery, viability and T-cell function.

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    Germann, Anja; Oh, Young-Joo; Schmidt, Tomm; Schön, Uwe; Zimmermann, Heiko; von Briesen, Hagen

    2013-10-01

    The ability to analyze cryopreserved peripheral blood mononuclear cell (PBMC) from biobanks for antigen-specific immunity is necessary to evaluate response to immune-based therapies. To ensure comparable assay results, collaborative research in multicenter trials needs reliable and reproducible cryopreservation that maintains cell viability and functionality. A standardized cryopreservation procedure is comprised of not only sample collection, preparation and freezing but also low temperature storage in liquid nitrogen without any temperature fluctuations, to avoid cell damage. Therefore, we have developed a storage approach to minimize suboptimal storage conditions in order to maximize cell viability, recovery and T-cell functionality. We compared the influence of repeated temperature fluctuations on cell health from sample storage, sample sorting and removal in comparison to sample storage without temperature rises. We found that cyclical temperature shifts during low temperature storage reduce cell viability, recovery and immune response against specific-antigens. We showed that samples handled under a protective hood system, to avoid or minimize such repeated temperature rises, have comparable cell viability and cell recovery rates to samples stored without any temperature fluctuations. Also T-cell functionality could be considerably increased with the use of the protective hood system compared to sample handling without such a protection system. This data suggests that the impact of temperature fluctuation on cell integrity should be carefully considered in future clinical vaccine trials and consideration should be given to optimal sample storage conditions. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

  10. Influence of biological fluids in bacterial viability on different hospital surfaces and fomites.

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    Esteves, Deigilam C; Pereira, Valeria C; Souza, Joyce M; Keller, Rogéria; Simões, Rebeca D; Winkelstroter Eller, Lizziane K; Rodrigues, Marcus Vinicius P

    2016-03-01

    The hospital environment is susceptible to bacterial contamination along with survival in fomites and surfaces, allowing dissemination of potential pathogenic strains. The present research aimed to evaluate the influence of biological fluids in bacterial viability on fomites and surfaces commonly present in nosocomial environment. Four different fomites and surfaces (ceramic floor, cotton fabric fragments and synthetic fibers, and eggcrate foam mattress) were contaminated with potential pathogens (Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa, and Klebsiella pneumoniae), then submitted to influence of biological fluids (blood, urine, artificial saliva). The viability of strains was evaluated at 24 hours after contamination and then in intervals of 7 days, by the colony-forming unit count technique. S aureus presented viability (>70 days) in all conditions tested, E faecalis and K pneumoniae had decreased viability over time, and E coli did not exhibit a growth relationship with surfaces or fluids. Persistence and adaptability capacity of potential pathogens in fomites and surfaces exposed to the patient are important for guidance, planning, and outlining of protocols for microorganism dissemination control and prevention in the health care environment. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  11. Glycerol Monolaurate Inhibits Lipase Production by Clinical Ocular Isolates Without Affecting Bacterial Cell Viability.

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    Flanagan, Judith Louise; Khandekar, Neeta; Zhu, Hua; Watanabe, Keizo; Markoulli, Maria; Flanagan, John Terence; Papas, Eric

    2016-02-01

    We sought to determine the relative lipase production of a range of ocular bacterial isolates and to assess the efficacy of glycerol monolaurate (GML) in inhibiting this lipase production in high lipase-producing bacteria without affecting bacterial cell growth. Staphylococcus aureus,Staphylococcus epidermidis,Propionibacterium acnes, and Corynebacterium spp. were inoculated at a density of 10(6)/mL in varying concentrations of GML up to 25 μg/mL for 24 hours at 37 °C with constant shaking. Bacterial suspensions were centrifuged, bacterial cell density was determined, and production of bacterial lipase was quantified using a commercial lipase assay kit. Staphylococcus spp. produced high levels of lipase activity compared with P. acnes and Corynebacterium spp. GML inhibited lipase production by Staphylococcal spp. in a dose-dependent manner, with S. epidermidis lipase production consistently more sensitive to GML than S. aureus. Glycerol monolaurate showed significant (P lipase inhibition above concentrations of 15 μg/mL in S. aureus and was not cytotoxic up to 25 μg/mL. For S. epidermidis, GML showed significant (P lipase inhibition above 7.5 μg/mL. Lipase activity varied between species and between strains. Staphylococcal spp. produced higher lipase activity compared with P. acnes and Corynebacterium spp. Glycerol monolaurate inhibited lipase production by S. aureus and S. epidermidis at concentrations that did not adversely affect bacterial cell growth. GML can be used to inhibit ocular bacterial lipase production without proving detrimental to commensal bacteria viability.

  12. Molecular viability testing of bacterial pathogens from a complex human sample matrix.

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    Kris M Weigel

    Full Text Available Assays for bacterial ribosomal RNA precursors (pre-rRNA have been shown to distinguish viable from inactivated bacterial cells in drinking water samples. Because the synthesis of pre-rRNA is rapidly induced by nutritional stimulation, viable bacteria can be distinguished from inactivated cells and free nucleic acids by measuring the production of species-specific pre-rRNA in samples that have been briefly stimulated with nutrients. Here, pre-rRNA analysis was applied to bacteria from serum, a human sample matrix. In contrast to drinking water, serum is rich in nutrients that might be expected to mask the effects of nutritional stimulation. Reverse transcriptase quantitative polymerase chain reaction (RT-qPCR assays were used to detect pre-rRNA of four bacterial species: Acinetobacter baumannii, Pseudomonas aeruginosa, Staphylococcus aureus, and the Mycobacterium tuberculosis complex. These species were chosen for their clinical significance and phylogenetic diversity (Proteobacteria, Firmicutes, and Actinobacteria. To maximize resolving power, pre-rRNA was normalized to genomic DNA of each pathogen. When viable cells were shifted from serum to bacteriological culture medium, rapid replenishment of pre-rRNA was always observed. Cells of P. aeruginosa that were inactivated in the presence of serum exhibited no pre-rRNA response to nutritional stimulation, despite strong genomic DNA signals in these samples. When semi-automated methods were used, pre-rRNA analysis detected viable A. baumannii cells in serum at densities of ≤100 CFU/mL in <5.5 hours. Originally developed for rapid microbiological analysis of drinking water, ratiometric pre-rRNA analysis can also assess the viability of bacterial cells derived from human specimens, without requiring bacteriological culture.

  13. Viability analysis of heat recovery solution for industrial process of roasting coffee

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    Kljajić Miroslav V.

    2016-01-01

    Full Text Available Every industrial heat recovery solution is specific engineering challenge but not because predicted energy rationalization or achieved energy savings but potential unavoidable technological deviations and consequences on related processes and for sure, high investment because of delicate design and construction. Often, the energy savings in a particular segment of the industrial process is a main goal. However, in the food industry, especially roasting coffee, additional criteria has to be strictly observed and fulfilled. Such criteria may include prescribed and uniform product quality, compliance with food safety standards, stability of the processes etc., and all in the presence of key process parameters variability, inconsistency of raw material composition and quality, complexity of measurement and analytical methods etc. The paper respects all circumstances and checks viability of proposed recovery solution. The paper analyzes the possibility of using waste heat from the roasting process to ensure shortening of roasting cycle, reduction of fuel consumption and increasing capacity of roasting lines on daily basis. Analysis concludes that effects are valuable and substantial, although the complete solution is on the threshold of economic sustainability with numerous opportunities to improve of both technical and economic indicators. The analysis combines measuring and analytical methods with standard cost-benefit analysis. Conclusions are derived from measurements and calculations of key parameters in the operating conditions and checked by experimental methods. Test results deviate from 10 to 15%, in relation with parameters in main production line.

  14. Monitoring water supplies for weaponized bacteria and bacterial toxins using rapid fluorescence-based viability and affinity assays

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    Van Tassell, Roger L.; Evans, Mishell

    2004-03-01

    The rapid detection of weaponized bacteria and toxins is a major problem during a biological attack. Although sensitive detection formats exist for many biowarfare agents, they often require advanced training and complex procedures. Luna has developed simple, rapid means for determining the presence of pathogens and bacterial toxins in water supplies using fluorescence-based assays that can be adapted for field use. The batteries of rapid assays are designed for i) determining cell viability and bacterial loads by exploiting metabolic markers (e.g., acid-production, redox potentials, etc) and ii) detecting bacterial toxins using fluorescent, polymerized affinity liposomes (fluorosomes). The viability assays were characterized using E. coli, S. aureus and the anthrax simulant, B. globigii. The viability assays detected bacterial loads of ~ 104 CFU/ml and with simple filtration ~ 100CFU/ml could be detected. The affinity fluorosomes were characterized using cholera toxin (CT). Affinity liposomes displaying GM1 and anti-CT antibodies could detect CT at water susceptible to sabotage could be easily monitored and confirmed for specific agents using simple, general and specific fluorescence-based detection schemes based on metabolism and ligand-target interactions.

  15. Bacterial viability and physical properties of antibacterially modified experimental dental resin composites.

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    Stefan Rüttermann

    Full Text Available PURPOSE: To investigate the antibacterial effect and the effect on the material properties of a novel delivery system with Irgasan as active agent and methacrylated polymerizable Irgasan when added to experimental dental resin composites. MATERIALS AND METHODS: A delivery system based on novel polymeric hollow beads, loaded with Irgasan and methacrylated polymerizable Irgasan as active agents were used to manufacture three commonly formulated experimental resin composites. The non-modified resin was used as standard (ST. Material A contained the delivery system providing 4 % (m/m Irgasan, material B contained 4 % (m/m methacrylated Irgasan and material C 8 % (m/m methacrylated Irgasan. Flexural strength (FS, flexural modulus (FM, water sorption (WS, solubility (SL, surface roughness Ra, polymerization shrinkage, contact angle Θ, total surface free energy γS and its apolar γS (LW, polar γS (AB, Lewis acid γS (+and base γS (- term as well as bacterial viability were determined. Significance was p < 0.05. RESULTS: The materials A to C were not unacceptably influenced by the modifications and achieved the minimum values for FS, WS and SL as requested by EN ISO 4049 and did not differ from ST what was also found for Ra. Only A had lower FM than ST. Θ of A and C was higher and γS (AB of A and B was lower than of ST. Materials A to C had higher γS (+ than ST. The antibacterial effect of materials A to C was significantly increased when compared with ST meaning that significantly less vital cells were found. CONCLUSION: Dental resin composites with small quantities of a novel antibacterially doped delivery system or with an antibacterial monomer provided acceptable physical properties and good antibacterial effectiveness. The sorption material being part of the delivery system can be used as a vehicle for any other active agent.

  16. Resveratrol Antagonizes Antimicrobial Lethality and Stimulates Recovery of Bacterial Mutants.

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    Yuanli Liu

    Full Text Available Reactive oxygen species (ROS; superoxide, peroxide, and hydroxyl radical are thought to contribute to the rapid bactericidal activity of diverse antimicrobial agents. The possibility has been raised that consumption of antioxidants in food may interfere with the lethal action of antimicrobials. Whether nutritional supplements containing antioxidant activity are also likely to interfere with antimicrobial lethality is unknown. To examine this possibility, resveratrol, a popular antioxidant dietary supplement, was added to cultures of Escherichia coli and Staphylococcus aureus that were then treated with antimicrobial and assayed for bacterial survival and the recovery of mutants resistant to an unrelated antimicrobial, rifampicin. Resveratrol, at concentrations likely to be present during human consumption, caused a 2- to 3-fold reduction in killing during a 2-hr treatment with moxifloxacin or kanamycin. At higher, but still subinhibitory concentrations, resveratrol reduced antimicrobial lethality by more than 3 orders of magnitude. Resveratrol also reduced the increase in reactive oxygen species (ROS characteristic of treatment with quinolone (oxolinic acid. These data support the general idea that the lethal activity of some antimicrobials involves ROS. Surprisingly, subinhibitory concentrations of resveratrol promoted (2- to 6-fold the recovery of rifampicin-resistant mutants arising from the action of ciprofloxacin, kanamycin, or daptomycin. This result is consistent with resveratrol reducing ROS to sublethal levels that are still mutagenic, while the absence of resveratrol allows ROS levels to high enough to kill mutagenized cells. Suppression of antimicrobial lethality and promotion of mutant recovery by resveratrol suggests that the antioxidant may contribute to the emergence of resistance to several antimicrobials, especially if new derivatives and/or formulations of resveratrol markedly increase bioavailability.

  17. Disinfection of titanium dioxide nanotubes using super-oxidized water decrease bacterial viability without disrupting osteoblast behavior

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    Beltrán-Partida, Ernesto [Department of Biomaterials, Dental Materials and Tissue Engineering, Faculty of Dentistry Mexicali, Autonomous University of Baja California, Av. Zotoluca and Chinampas St., 21040 Mexicali, Baja California (Mexico); Department of Corrosion and Materials, Engineering Institute, Autonomous University of Baja California, Blvd. Benito Juarez and Normal St., 21280 Mexicali, Baja California (Mexico); Valdez-Salas, Benjamín, E-mail: benval@uabc.edu.mx [Department of Corrosion and Materials, Engineering Institute, Autonomous University of Baja California, Blvd. Benito Juarez and Normal St., 21280 Mexicali, Baja California (Mexico); Escamilla, Alan; Curiel, Mario [Department of Corrosion and Materials, Engineering Institute, Autonomous University of Baja California, Blvd. Benito Juarez and Normal St., 21280 Mexicali, Baja California (Mexico); Valdez-Salas, Ernesto [Ixchel Medical Centre, Av. Bravo y Obregón, 21000 Mexicali, Baja California (Mexico); Nedev, Nicola [Department of Corrosion and Materials, Engineering Institute, Autonomous University of Baja California, Blvd. Benito Juarez and Normal St., 21280 Mexicali, Baja California (Mexico); Bastidas, Jose M. [National Centre for Metallurgical Research, CSIC, Av. Gregorio del Amo 8, 28040 Madrid (Spain)

    2016-03-01

    Amorphous titanium dioxide (TiO{sub 2}) nanotubes (NTs) on Ti6Al4V alloy were synthesized by anodization using a commercially available super-oxidized water (SOW). The NT surfaces were sterilized by ultraviolet (UV) irradiation and disinfected using SOW. The adhesion and cellular morphology of pig periosteal osteoblast (PPO) cells and the behavior of Staphylococcus aureus (S. aureus) cultured on the sterilized and disinfected surfaces were investigated. A non-anodized Ti6Al4V disc sterilized by UV irradiation (without SOW) was used as control. The results of this study reveal that the adhesion, morphology and filopodia development of PPO cells in NTs are dramatically improved, suggesting that SOW cleaning may not disrupt the benefits obtained by NTs. Significantly decreased bacterial viability in NTs after cleaning with SOW and comparing with non-cleaned NTs was seen. The results suggest that UV and SOW could be a recommendable method for implant sterilization and disinfection without altering osteoblast behavior while decreasing bacterial viability. - Highlights: • The effect of super-oxidized water cleaning was studied on Ti6Al4V nanotubes. • Super oxidized-water cleaning caused a decline in S. aureus viability. • Osteoblast behavior was not disrupted after super-oxidized water disinfection. • Super-oxidized water is suggested as a cleaning protocol for TiO{sub 2} nanotubes.

  18. Evaluation of Escherichia coli viability by flow cytometry: A method for determining bacterial responses to antibiotic exposure.

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    Boi, Paola; Manti, Anita; Pianetti, Anna; Sabatini, Luigia; Sisti, Davide; Rocchi, Marco Bruno; Bruscolini, Francesca; Galluzzi, Luca; Papa, Stefano

    2015-01-01

    In this study, we check for the presence of specific resistance genes by polymerase chain reaction (PCR) and then we used flow cytometry (FCM) to evaluate antibiotic-induced effects in different strains of Escherichia coli (E. coli). The presence of resistance genes was investigated by PCR in 10 strains of E. coli isolated from Foglia River. Bacterial responses to different antibiotics were also tested with FCM techniques by evaluating both the degree of decrease in viability and the light scatter changes in all of the strains. PCR revealed that only one strain exhibits the presence of one resistance gene. Despite this, analyses of strains using FCM evidenced the presence of viable subpopulations after antibiotic treatment. Furthermore, analyses of scatter signals revealed profound changes in the Forward Scatter and Side Scatter of the bacterial populations as a consequence of antibiotic exposure, confirming the viability and membrane potential data. The riverine strains were in general less sensitive to antibiotics than the reference strain (ATCC 25922). Antibiotic resistance is a widespread phenomena. The multiparametric approach based on FCM used in this study, providing results about different aspects (cell viability, membrane potential, light scatter changes), may overcome the limitation of PCR and could represent an adequate method for the evaluation of bacteria responses to antibiotic exposure. © 2014 International Clinical Cytometry Society.

  19. Recovery and identification of bacterial DNA from illicit drugs.

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    Cho, Kaymann T; Richardson, Michelle M; Kirkbride, K Paul; McNevin, Dennis; Nelson, Michelle; Pianca, Dennis; Roffey, Paul; Gahan, Michelle E

    2014-02-01

    Bacterial infections, including Bacillus anthracis (anthrax), are a common risk associated with illicit drug use, particularly among injecting drug users. There is, therefore, an urgent need to survey illicit drugs used for injection for the presence of bacteria and provide valuable information to health and forensic authorities. The objectives of this study were to develop a method for the extraction of bacterial DNA from illicit drugs and conduct a metagenomic survey of heroin and methamphetamine seized in the Australian Capital Territory during 2002-2011 for the presence of pathogens. Trends or patterns in drug contamination and their health implications for injecting drug users were also investigated. Methods based on the ChargeSwitch(®)gDNA mini kit (Invitrogen), QIAamp DNA extraction mini kit (QIAGEN) with and without bead-beating, and an organic phenol/chloroform extraction with ethanol precipitation were assessed for the recovery efficiency of both free and cellular bacterial DNA. Bacteria were identified using polymerase chain reaction and electrospray ionization-mass spectrometry (PCR/ESI-MS). An isopropanol pre-wash to remove traces of the drug and diluents, followed by a modified ChargeSwitch(®) method, was found to efficiently lyse cells and extract free and cellular DNA from Gram-positive and Gram-negative bacteria in heroin and methamphetamine which could then be identified by PCR/ESI-MS. Analysis of 12 heroin samples revealed the presence of DNA from species of Comamonas, Weissella, Bacillus, Streptococcus and Arthrobacter. No organisms were detected in the nine methamphetamine samples analysed. This study develops a method to extract and identify Gram-positive and Gram-negative bacteria from illicit drugs and demonstrates the presence of a range of bacterial pathogens in seized drug samples. These results will prove valuable for future work investigating trends or patterns in drug contamination and their health implications for injecting drug

  20. Seeking the environmental source of Leptospirosis reveals durable bacterial viability in river soils.

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    Roman Thibeaux

    2017-02-01

    Full Text Available Leptospirosis is an important re-emerging infectious disease that affects humans worldwide. Infection occurs from indirect environment-mediated exposure to pathogenic leptospires through contaminated watered environments. The ability of pathogenic leptospires to persist in the aqueous environment is a key factor in transmission to new hosts. Hence, an effort was made to detect pathogenic leptospires in complex environmental samples, to genotype positive samples and to assess leptospiral viability over time.We focused our study on human leptospirosis cases infected with the New Caledonian Leptospira interrogans serovar Pyrogenes. Epidemiologically related to freshwater contaminations, this strain is responsible for ca. 25% of human cases in New Caledonia. We screened soil and water samples retrieved from suspected environmental infection sites for the pathogen-specific leptospiral gene lipL-32. Soil samples from all suspected infection sites tested showed detectable levels of pathogenic leptospiral DNA. More importantly, we demonstrated by viability qPCR that those pathogenic leptospires were viable and persisted in infection sites for several weeks after the index contamination event. Further, molecular phylogenetic analyses of the leptospiral lfb-1 gene successfully linked the identity of environmental Leptospira to the corresponding human-infecting strain.Altogether, this study illustrates the potential of quantitative viability-PCR assay for the rapid detection of viable leptospires in environmental samples, which might open avenues to strategies aimed at assessing environmental risk.

  1. Energetic and economic viability of olive stone recovery as a renewable energy source: a Southern Italy case study

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    Alessandro Parenti

    2014-10-01

    Full Text Available The recovery of olive stones for biofuel is becoming increasingly widespread in olive milling plants. In this study we look at the economic and energetic benefits of using a de-stoner machine in a small-to-medium sized oil milling plant. The performance of the olive stone recovery system was evaluated over a full olive oil production season. The energetic viability of the de-stoner was assessed using a Life Cycle Assessment approach, and the break-even point was achieved when about 56 tons of olives had been processed, which is less than the annual production of the mill in question. Similarly, in economic terms, the machine covered its costs after about a quarter of its technical life.

  2. Effect of KCl substitution on bacterial viability of Escherichia coli (ATCC 25922) and selected probiotics.

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    Gandhi, Akanksha; Cui, Yuxiang; Zhou, Mingyang; Shah, Nagendra P

    2014-10-01

    Excessive intake of NaCl has been associated with the increased risk of several diseases, particularly hypertension. Strategies to reduce sodium intake include substitution of NaCl with other salts, such as KCl. In this study, the effects of NaCl reduction and its substitution with KCl on cell membranes of a cheese starter bacterium (Lactococcus lactis ssp. lactis), probiotic bacteria (Bifidobacterium longum, Lactobacillus acidophilus, and Lactobacillus casei), and a pathogenic bacterium (Escherichia coli) were investigated using Fourier-transform infrared (FTIR) spectroscopy. A critical NaCl concentration that inhibited the viability of E. coli without affecting the viability of probiotic bacteria significantly was determined. To find the critical NaCl concentration, de Man, Rogosa, and Sharpe (MRS) broth was supplemented with a range of NaCl concentrations [0 (control), 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, and 5.0%], and the effect on cell viability and FTIR spectra was monitored for all bacteria. A NaCl concentration of 2.5% was found to be the critical level of NaCl to inhibit E. coli without significantly affecting the viability of most of the probiotic bacteria and the cheese starter bacterium. The FTIR spectral analysis also highlighted the changes that occurred mainly in the amide regions upon increasing the NaCl concentration from 2.5 to 3.0% in most of the bacteria. Escherichia coli and B. longum were more sensitive to substitution of NaCl with KCl, compared with Lb. acidophilus, Lb. casei, and Lc. lactis ssp. lactis. To evaluate the effect of substitution of NaCl with KCl, substitution was carried out at the critical total salt concentration (2.5%, wt/vol) at varying concentrations (0, 25, 50, 75, and 100% KCl). The findings suggest that 50% substitution of NaCl with KCl, at 2.5% total salt, could inhibit E. coli without affecting the probiotic bacteria. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights

  3. Evaluation of resistance development and viability recovery by a non-enveloped virus after repeated cycles of aPDT.

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    Costa, Liliana; Tomé, João P C; Neves, Maria G P M S; Tomé, Augusto C; Cavaleiro, José A S; Faustino, Maria A F; Cunha, Ângela; Gomes, Newton C M; Almeida, Adelaide

    2011-09-01

    Nowadays, the emergence of drug resistant microorganisms is a public health concern. The antimicrobial photodynamic therapy (aPDT) has an efficient action against a wide range of microorganisms and can be viewed as an alternative approach for treating microbial infections. The aim of this study was to determine if a model target virus (T4-like bacteriophage), in the presence of the tricationic porphyrin 5,10,15-tris(1-methylpyridinium-4-yl)-20-(pentafluorophenyl)porphyrin tri-iodide (Tri-Py(+)-Me-PF), can develop resistance to aPDT and recover its viability after photodynamic treatments. To assess the development of aPDT resistance after repeated treatments, a suspension of T4-like bacteriophage was irradiated with white light (40 Wm(-2)) for 120 min in the presence of 5.0 μM of Tri-Py(+)-Me-PF (99.99% of inactivation) and new phage suspensions were produced from the surviving phages, after each cycle of light exposure. The procedure was repeated ten times. To evaluate the recovery of viral viability after photoinactivation, a suspension of T4-like bacteriophage was irradiated with white light for 120 min in the presence of 5.0 μM of Tri-Py(+)-Me-PF on five consecutive days. In each day, an aliquot of the irradiated suspension was plated and the number of lysis plaques was counted after 24, 48, 72, 96 and 120 h of dark incubation at 37 °C. The profile of bacteriophage photoinactivation did not change after ten consecutive cycles and no recovery of viability was detected after five accumulated cycles of photodynamic treatment. The results suggest that aPDT represents a valuable and promising alternative therapy to treat viral infections, overcoming the problem of microbial resistance. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Actual and potential use of population viability analyses in recovery of plant species listed under the US endangered species act.

    Science.gov (United States)

    Zeigler, Sara L; Che-Castaldo, Judy P; Neel, Maile C

    2013-12-01

    Use of population viability analyses (PVAs) in endangered species recovery planning has been met with both support and criticism. Previous reviews promote use of PVA for setting scientifically based, measurable, and objective recovery criteria and recommend improvements to increase the framework's utility. However, others have questioned the value of PVA models for setting recovery criteria and assert that PVAs are more appropriate for understanding relative trade-offs between alternative management actions. We reviewed 258 final recovery plans for 642 plants listed under the U.S. Endangered Species Act to determine the number of plans that used or recommended PVA in recovery planning. We also reviewed 223 publications that describe plant PVAs to assess how these models were designed and whether those designs reflected previous recommendations for improvement of PVAs. Twenty-four percent of listed species had recovery plans that used or recommended PVA. In publications, the typical model was a matrix population model parameterized with ≤5 years of demographic data that did not consider stochasticity, genetics, density dependence, seed banks, vegetative reproduction, dormancy, threats, or management strategies. Population growth rates for different populations of the same species or for the same population at different points in time were often statistically different or varied by >10%. Therefore, PVAs parameterized with underlying vital rates that vary to this degree may not accurately predict recovery objectives across a species' entire distribution or over longer time scales. We assert that PVA, although an important tool as part of an adaptive-management program, can help to determine quantitative recovery criteria only if more long-term data sets that capture spatiotemporal variability in vital rates become available. Lacking this, there is a strong need for viable and comprehensive methods for determining quantitative, science-based recovery criteria for

  5. Partial drying accelerates bacterial growth recovery to rewetting

    DEFF Research Database (Denmark)

    Meisner, Annelein; Leizeaga, Ainara; Rousk, Johannes

    2017-01-01

    Fluctuations in soil moisture create drying-rewetting events affecting the activity of microorganisms. Microbial responses to drying-rewetting are mostly studied in soils that are air-dried before rewetting. Upon rewetting, two patterns of bacterial growth have been observed. In the Type 1 pattern......, bacterial growth rates increase immediately in a linear fashion. In the Type 2 pattern, bacterial growth rates increase exponentially after a lag period. However, soils are often only partially dried. Partial drying (higher remaining moisture content before rewetting) may be considered a less harsh...... treatment compared with air-drying. We hypothesized that a soil with a Type 2 response upon rewetting air-dried soil would transform into a Type 1 response if dried partially before rewetting. Two soils were dried to a gradient of different moisture content. Respiration and bacterial growth rates were...

  6. Functional recovery of biofilm bacterial communities after copper exposure

    International Nuclear Information System (INIS)

    Boivin, Marie-Elene Y.; Massieux, Boris; Breure, Anton M.; Greve, Gerdit D.; Rutgers, Michiel; Admiraal, Wim

    2006-01-01

    Potential of bacterial communities in biofilms to recover after copper exposure was investigated. Biofilms grown outdoor in shallow water on glass dishes were exposed in the laboratory to 0.6, 2.1, 6.8 μmol/l copper amended surface water and a reference and subsequently to un-amended surface water. Transitions of bacterial communities were characterised with denaturing gradient gel electrophoresis (DGGE) and community-level physiological profiles (CLPP). Exposure to 6.8 μmol/l copper provoked distinct changes in DGGE profiles of bacterial consortia, which did not reverse upon copper depuration. Exposure to 2.1 and 6.8 μmol/l copper was found to induce marked changes in CLPP of bacterial communities that proved to be reversible during copper depuration. Furthermore, copper exposure induced the development of copper-tolerance, which was partially lost during depuration. It is concluded that bacterial communities exposed to copper contaminated water for a period of 26 days are capable to restore their metabolic attributes after introduction of unpolluted water in aquaria for 28 days. - Genetically different bacterial communities can have similar functions and tolerance to copper

  7. Influence of addition of different antibiotics in semen diluent on viable bacterial count and spermatozoal viability of Awassi ram semen

    Directory of Open Access Journals (Sweden)

    O I Azawi

    2012-04-01

    significantly reduced (P<0.05 sperm individual motility and percent live sperm and a significant increase (P<0.05 acrosomal defects was observed at 96 h of preservation in comparison to control and other antibiotics. Sperm viability was highly correlated with bacterial count in the control part of diluted semen (r = 0.794; P < 0.01. It could be concluded from the results of the present study that additions of cephalosporins (cefdinir or Cefoperazone sodium at the dose of 1 mg ml-1 were most effective amongst the antibiotics used in checking the bacterial growth and improving semen quality of Awassi ram. [Vet. World 2012; 5(2.000: 75-79

  8. Applicability of LIVE/DEAD BacLight stain with glutaraldehyde fixation for the measurement of bacterial abundance and viability in rainwater.

    Science.gov (United States)

    Hu, Wei; Murata, Kotaro; Zhang, Daizhou

    2017-01-01

    Rainwater contains substantial bacteria and rain is an efficient pathway for the dissemination of bacteria from the atmosphere to land and water surfaces. However, quantitative information on rainwater bacteria is very limited due to the lack of a reliable method. In this study, the epifluorescence microscopy enumeration with the LIVE/DEAD BacLight Bacterial Viability Kit stain was verified to quantify the abundance of viable and non-viable bacterial cells in rainwater, with the 4',6-diamidino-2-phenylindole (DAPI) stain for the reference of total cell counts. Results showed that the total counts of bacterial cells by LIVE/DEAD BacLight staining were consistent with those by DAPI staining, and the average detection efficiency was (109±29)%. The ratio of cell count with glutaraldehyde fixation to that without fixation was (106±5)% on average. The bacterial concentration in negative control was usually an order of magnitude lower than that in rainwater samples. However, in case of small precipitation, the abundance in negative control could be more than that in rainwater samples. These results indicate that the enumeration with LIVE/DEAD BacLight bacterial viability assay coupled with glutaraldehyde fixation and careful negative control investigation is an approach applicable to the measurement of the concentration and viability of bacterial cells in rainwater. Copyright © 2016. Published by Elsevier B.V.

  9. Functional recovery of biofilm bacterial communities after copper exposure.

    NARCIS (Netherlands)

    Boivin, Marie-Elène Y; Massieux, Boris; Breure, Anton M; Greve, Gerdit D; Rutgers, Michiel; Admiraal, Wim

    2006-01-01

    Potential of bacterial communities in biofilms to recover after copper exposure was investigated. Biofilms grown outdoor in shallow water on glass dishes were exposed in the laboratory to 0.6, 2.1, 6.8 micromol/l copper amended surface water and a reference and subsequently to un-amended surface

  10. Autogenic succession and deterministic recovery following disturbance in soil bacterial communities

    DEFF Research Database (Denmark)

    Jurburg, Stephanie D.; Nunes, Ines Marques; Stegen, James C.

    2017-01-01

    slowed down, and a stability phase (after 29 days), during which the community tended towards its original composition. Phylogenetic turnover patterns indicated that the community experienced stronger deterministic selection during recovery. Thus, soil bacterial communities, despite their extreme...... to understand the successional trajectory of soil bacterial communities following disturbances and the mechanisms controlling these dynamics at a scale relevant for these organisms, we subjected soil microcosms to a heat disturbance and followed the community composition of active bacteria over 50 days...

  11. Assessment of viability of the nematode eggs (Ascaris, Toxocara, Trichuris) in sewage sludge with the use of LIVE/DEAD Bacterial Viability Kit.

    Science.gov (United States)

    Dąbrowska, Joanna; Zdybel, Jolanta; Karamon, Jacek; Kochanowski, Maciej; Stojecki, Krzysztof; Cencek, Tomasz; Kłapeć, Teresa

    2014-01-01

    Sewage sludges from wastewater treatment plants may contain live parasite eggs, which can be a source of humans and animals infection. According to the current rules, parasitological examination includes detection of the Ascaris spp., Trichuris spp. and Toxocara spp. eggs and estimation of their viability. The viability assessment based only on the incubation and observation of isolated egg is long and imprecise. The aim of this study was to develop sensitive and less labour-intensive methods for assessing viability of Ascaris spp., Toxocara spp. and Trichuris spp. eggs in sewage sludge. For this purpose, LIVE/DEAD Kit was used. Firstly, the possibility of distinguishing between live and dead eggs in water was assessed. Secondly, an appropriate amount of dyeing mixture needed to distinguish the live and dead eggs in the sewage sludge was determined using experimentally enriched samples and naturally contaminated samples of sludge. Eggs were isolated from the samples by own method which was a combination of flotation and sedimentation, preceded by a long mixing. After the last stage of the procedure, sediment containing the eggs of parasites was stained by LIVE/DEAD kit according to the manufacturer instructions, but with the use of different variants of dyes mixture concentration. The investigation showed that live and dead eggs of these three parasites could be differed by this method with the use of proper concentration of dyes. Live eggs were stained in green (Ascaris and Trichuris) and green-blue (Toxocara). However, all types of dead eggs were red coloured. The study demonstrated that after some modifications (resulted from the nature of the samples) the LIVE/DEAD kit is useful for assessing the viability of Toxocara, Ascaris and Trichuris eggs occurring in the sludge.

  12. Investigation of spore forming bacterial flooding for enhanced oil recovery in a North Sea chalk Reservoir

    DEFF Research Database (Denmark)

    Halim, Amalia Yunita; Nielsen, Sidsel Marie; Eliasson Lantz, Anna

    2015-01-01

    Bacillus licheniformis 421 was used as it was shown to be a good candidate in a previous study. Bacterial spore can penetrate deeper into the chalk rock, squeezing through the pore throats. Our results showed that injection of B. licheniformis 421 as a tertiary oil recovery method, in the residual oil...

  13. Temperature effects on recovery time of bacterial growth after rewetting dry soil.

    Science.gov (United States)

    Maienza, Anita; Bååth, Erland

    2014-11-01

    The effect of temperature on the recovery of bacterial growth after rewetting dry soil was measured in a soil that responded with bacterial growth increasing immediately upon rewetting in a linear fashion (type (i) response sensu Meisner et al. (Soil Biol Biochem 66: 188-192, 2013)). The soil was air-dried for 4 days and then rewetted at different temperatures. Bacterial growth over time was then estimated using the leucine incorporation method. At 25 °C, the recovery of bacterial growth to levels of a wet control soil was rapid, within 6 h, while at 15 °C, recovery time increased to around 60 h, becoming more than a week at 5 °C. The temperature dependency of the recovery time was well modeled by a square root function. Thus, temperature will not only directly affect growth rates but also affect length of transition periods, like resuscitation after a drying event. The temperature during the rewetting event thus has to be taken into consideration when analyzing the microbial response dynamics.

  14. Impact of the freeze-drying process on product appearance, residual moisture content, viability, and batch uniformity of freeze-dried bacterial cultures safeguarded at culture collections.

    Science.gov (United States)

    Peiren, Jindrich; Hellemans, Ann; De Vos, Paul

    2016-07-01

    In this study, causes of collapsed bacterial cultures in glass ampoules observed after freeze-drying were investigated as well as the influence of collapse on residual moisture content (RMC) and viability. Also, the effect of heat radiation and post freeze-drying treatments on the RMC was studied. Cake morphologies of 21 bacterial strains obtained after freeze-drying with one standard protocol could be classified visually into four major types: no collapse, porous, partial collapse, and collapse. The more pronounced the collapse, the higher residual moisture content of the freeze-dried product, ranging from 1.53 % for non-collapsed products to 3.62 % for collapsed products. The most important cause of collapse was the mass of the inserted cotton plug in the ampoule. Default cotton plugs with a mass between 21 and 30 mg inside the ampoule did not affect the viability of freeze-dried Aliivibrio fischeri LMG 4414(T) compared to ampoules without cotton plugs. Cotton plugs with a mass higher than 65 mg inside the ampoule induced a full collapsed product with rubbery look (melt-back) and decreasing viability during storage. Heat radiation effects in the freeze-drying chamber and post freeze-drying treatments such as exposure time to air after freeze-drying and manifold drying time prior to heat sealing of ampoules influenced the RMC of freeze-dried products. To produce uniform batches of freeze-dried bacterial strains with intact cake structures and highest viabilities, inserted cotton plugs should not exceed 21 mg per ampoule. Furthermore, heat radiation effects should be calculated in the design of the primary drying phase and manifold drying time before heat sealing should be determined as a function of exposure time to air.

  15. Direct analysis of bacterial viability in endotracheal tube biofilm from a pig model of methicillin-resistant Staphylococcus aureus pneumonia following antimicrobial therapy.

    Science.gov (United States)

    Fernández-Barat, Laia; Li Bassi, Gianluigi; Ferrer, Miquel; Bosch, Anna; Calvo, Maria; Vila, Jordi; Gabarrús, Albert; Martínez-Olondris, Pilar; Rigol, Montse; Esperatti, Mariano; Luque, Néstor; Torres, Antoni

    2012-07-01

    Confocal laser scanning microscopy (CLSM) helps to observe the biofilms formed in the endotracheal tube (ETT) of ventilated subjects and to determine its structure and bacterial viability using specific dyes. We compared the effect of three different treatments (placebo, linezolid, and vancomycin) on the bacterial biofilm viability captured by CLSM. Eight pigs with pneumonia induced by methicillin-resistant Staphylococcus aureus (MRSA) were ventilated up to 96 h and treated with linezolid, vancomycin, or placebo (controls). ETT images were microscopically examined after staining with the live/dead(®) BacLight(™) Kit (Invitrogen, Barcelona, Spain) with a confocal laser scanning microscope. We analyzed 127 images obtained by CLSM. The median ratio of live/dead bacteria was 0.51, 0.74, and 1 for the linezolid, vancomycin, and control groups, respectively (P = 0.002 for the three groups); this ratio was significantly lower for the linezolid group, compared with the control group (P = 0.001). Images showed bacterial biofilm attached and non-attached to the ETT surface but growing within secretions accumulated inside ETT. Systemic treatment with linezolid is associated with a higher proportion of dead bacteria in the ETT biofilm of animals with MRSA pneumonia. Biofilm clusters not necessarily attach to the ETT surface. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  16. Isolation and Identification of an Indigenous Probiotic Lactobacillus Strain: Its Encapsulation with Natural Branched Polysaccharids to Improve Bacterial Viability

    OpenAIRE

    Nafiseh Sadat Foroutan; Fatemeh Tabandeh; Mahvash Khodabandeh; Naheed Mojgani; Amir Maghsoudi; Meisam Moradi

    2017-01-01

    Background and Objective: Probiotics have to reach their site of action in certain numbers in order to exhibit positive health effects. Encapsulation has shown remarkable enhancing effects on probiotic survival in simulated gastric conditions compared to free bacteria. The purpose of this study was identification and evaluation of a potential probiotic strain using encapsulation process by new carriers in order to improve probiotic viability during in vitro simulated conditions.Material and M...

  17. Correlation of bacterial viability with uptake of (14C) acetate into phenolic glycolipid-1 of Mycobacterium leprae within Schwannoma cells

    International Nuclear Information System (INIS)

    Mistry, Y.; Antia, N.H.; Mukherjee, R.

    1989-01-01

    The viability of Mycobacterium leprae, maintained within 33B Schwannoma cells, was estimated in terms of incorporation of ( 14 C) acetate into its specific phenolic glycolipid-1. This measure of viability was correlated with two other assays, viz., fluorescein diacetate/ethidium bromide staining and mouse footpad growth. Observation of a 2-fold increase in the number of intracellular Mycobacterium leprae over an experimental period of 12 days also corroborated this contention. Furthermore, on addition of anti-leprosy drugs to these intracellular Mycobacterium leprae there was significant decrease in phenolic glycolipid-1 synthesis indicative of loss of viability of the organisms. This study also established the importance of the host cell for active bacillary metabolism, as Mycobacterium leprae maintained in cell-free conditions showed no incorporation into phenolic glycolipid-1. Moreover, compromising the host's protein synthesis capacity with cycloheximide, also led to reduction in bacillary metabolism. As this system measures the metabolic synthesis of a unique Mycobacterium leprae component, it would be useful for development and screening of compounds acting against specific bacillary targets. (author). 19 refs., 5 tabs

  18. Autogenic succession and deterministic recovery following disturbance in soil bacterial communities

    Energy Technology Data Exchange (ETDEWEB)

    Jurburg, Stephanie D.; Nunes, Inês; Stegen, James C.; Le Roux, Xavier; Priemé, Anders; Sørensen, Søren J.; Salles, Joana Falcão

    2017-04-06

    The response of bacterial communities to environmental change may affect local to global nutrient cycles; however the dynamics of these communities following disturbance are poorly understood, and are generally attributed to abiotic factors. Here, we subjected soil microcosms to a heat disturbance and followed the community composition of active bacteria over 50 days of recovery. Phylogenetic turnover patterns indicated that biotic interactions shaped the community during recovery, and that the disturbance imposed a strong selective pressure that persisted for up to 10 days, after which the importance of stochastic processes increased. Three successional stages were detected: a primary response (1-4 days after disturbance) in which surviving taxa increased in abundance; a secondary response phase (10-29 days), during which community dynamics slowed down, and a stability phase (after 29 days), during which the community tended towards its original composition. Soil bacterial communities, despite their extreme diversity and functional redundancy, respond to disturbances like many macroecological systems and exhibit path-dependent, autogenic dynamics during secondary succession.

  19. Bacterial electroactivity and viability depends on the carbon nanotube-coated sponge anode used in a microbial fuel cell.

    Science.gov (United States)

    Ma, Hanyue; Xia, Tian; Bian, Congcong; Sun, Huihui; Liu, Zhuang; Wu, Chao; Wang, Xia; Xu, Ping

    2018-02-27

    The anode material is vital to improve the power generation of a microbial fuel cell (MFC). In this study, a carbon nanotube (CNT)-coated sponge with macro-porous structure, high surface area, and high conductivity was constructed as an anode to encapsulate Escherichia coli K12 (E. coli K12) cells. To achieve high power generation of the MFC, the optimal concentration of the CNT coating the sponge was found to be 30mgmL -1 . At this concentration, a maximum power density of 787Wm -3 and a chemical oxygen demand (COD) removal of 80.9% were obtained with a long stable electricity generation process in batch mode. This indicates that the biofilm on the CNT (30mgmL -1 )-coated sponge possessed excellent electroactivity and stability. Scanning electron microscope (SEM) images confirmed that the CNT-coated sponge provided a suitable microenvironment for E. coli K12 cells to maintain their attachment and colonization. Additionally, a CNT-dependent viability phenomenon of the E. coli K12 cells was discovered after electricity generation. This CNT-dependent viability of the E. coli K12 cells was stable and sustainable after storage at -20°C in a milk tube for one year. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Detecting the dormant: a review of recent advances in molecular techniques for assessing the viability of bacterial endospores.

    Science.gov (United States)

    Mohapatra, Bidyut R; La Duc, Myron T

    2013-09-01

    Due to their contribution to gastrointestinal and pulmonary disease, their ability to produce various deadly exotoxins, and their resistance to extreme temperature, pressure, radiation, and common chemical disinfecting agents, bacterial endospores of the Firmicutes phylum are a major concern for public and environmental health. In addition, the hardy and dormant nature of endospores renders them a particularly significant threat to the integrity of robotic extraterrestrial life-detection investigations. To prevent the contamination of critical surfaces with seemingly ubiquitous bacterial endospores, clean rooms maintained at exceedingly stringent cleanliness levels (i.e., fewer than 100,000 airborne particles per ft(3)) are used for surgical procedures, pharmaceutical processing and packaging, and fabrication and assembly of medical devices and spacecraft components. However, numerous spore-forming bacterial species have been reported to withstand typical clean room bioreduction strategies (e.g., UV lights, maintained humidity, paucity of available nutrients), which highlights the need for rapid and reliable molecular methods for detecting, enumerating, and monitoring the incidence of viable endospores. Robust means of evaluating and tracking spore burden not only provide much needed information pertaining to endospore ecophysiology in different environmental niches but also empower decontamination and bioreduction strategies aimed at sustaining the reliability and integrity of clean room environments. An overview of recent molecular advances in detecting and enumerating viable endospores, as well as the expanding phylogenetic diversity of pathogenic and clean room-associated spore-forming bacteria, ensues.

  1. Isolation and Identification of an Indigenous Probiotic Lactobacillus Strain: Its Encapsulation with Natural Branched Polysaccharids to Improve Bacterial Viability

    Directory of Open Access Journals (Sweden)

    Nafiseh Sadat Foroutan

    2017-06-01

    Full Text Available Background and Objective: Probiotics have to reach their site of action in certain numbers in order to exhibit positive health effects. Encapsulation has shown remarkable enhancing effects on probiotic survival in simulated gastric conditions compared to free bacteria. The purpose of this study was identification and evaluation of a potential probiotic strain using encapsulation process by new carriers in order to improve probiotic viability during in vitro simulated conditions.Material and Methods: A native Lactobacillus was isolated from yogurt, identified as Lactobacillus casei PM01 (NCBI registered and analyzed for probiotic properties alongside established probiotic strains of Lactobacillus acidophilus ATCC 43556, and Lactobacillus rhamnosus ATCC 7469. Acid and bile resistance, adhesion to Caco-2 cells and antibiotic resistance were evaluated. Lactobacillus casei PM01 was encapsulated with alginate, chitosan and natural branched polysaccharides (pectin, tragacanth gum and gum Arabic by using extrusion technique. Encapsulation efficiency, acidification activity and viability of entrapped Lactobacillus casei PM01 in simulated gastric pH were determined. Results and Conclusion: Based on the results, all the three strains could be considered as potential probiotics, and are good candidates for further in vitro and in vivo evaluation. The results showed that the survival of encapsulated Lactobacillus casei PM01 was significantly (p≤0.05 increased when it was incubated in simulated gastric pH. It can be concluded that indigenous Lactobacillus casei PM01 in encapsulated form is introduced as an efficient probiotic strain for using in dairy products.Conflict of interest: The authors declare no conflict of interest.

  2. Advanced Reservoir Characterization in the Antelope Shale to Establish the Viability of CO2 Enhanced Oil Recovery in California's Monterey Formation Siliceous Shales

    International Nuclear Information System (INIS)

    Morea, Michael F.

    1999-01-01

    The primary objective of this research is to conduct advanced reservoir characterization and modeling studies in the Antelope Shale reservoir. Characterization studies will be used to determine the technical feasibility of implementing a CO2 enhanced oil recovery project in the Antelope Shale in Buena Vista Hills Field. The Buena Vista Hills pilot CO2 project will demonstrate the economic viability and widespread applicability of CO2 flooding in fractured siliceous shale reservoirs of the San Joaquin Valley. The research consists of four primary work processes: (1) Reservoir Matrix and Fluid Characterization; (2) Fracture characterization; (3) reservoir Modeling and Simulation; and (4) CO2 Pilot Flood and Evaluation. Work done in these areas is subdivided into two phases or budget periods. The first phase of the project will focus on the application of a variety of advanced reservoir characterization techniques to determine the production characteristics of the Antelope Shale reservoir. Reservoir models based on the results of the characterization work will be used to evaluate how the reservoir will respond to secondary recovery and EOR processes. The second phase of the project will include the implementation and evaluation of an advanced enhanced oil recovery (EOR) pilot in the United Anticline (West Dome) of the Buena Vista Hills Field

  3. Simultaneous Gram and viability staining on activated sludge exposed to erythromycin: 3D CLSM time-lapse imaging of bacterial disintegration.

    Science.gov (United States)

    Louvet, Jean-Noël; Attik, Ghania; Dumas, Dominique; Potier, Olivier; Pons, Marie-Noëlle

    2011-11-01

    The effect of erythromycin on activated sludge bacteria according to their Gram type was investigated with 3-dimensional Confocal Laser Scanning Microscopy (CLSM) time-lapse imaging. The fluorescent stains SYTOX Green and Texas Red-X conjugate of wheat germ agglutinin stained dying bacteria and Gram(+) bacteria respectively. Time-lapse imaging allowed an understanding of the staining mechanism and the measurement of the death rate. In presence of erythromycin (10mg/L), Gram(+) bacteria had a higher mortality rate than the Gram(-) bacteria. This result suggests that antibiotic in wastewater could change the activated sludge bacteria composition, according to their Gram type by selecting the bacteria which are the least sensitive to the antibiotics. However bacterial death was followed by bacterial disintegration leading to a decrease in the fluorescence. Results suggested that the viability indicators based on membrane integrity should be used with a correct sampling method, which can give the initial quantity of living bacteria. Copyright © 2011 Elsevier GmbH. All rights reserved.

  4. Advanced Reservoir Characterization in the Antelope Shale to Establish the Viability of CO2 Enhanced Oil Recovery in California's Monterey Formation Siliceous Shales, Class III

    Energy Technology Data Exchange (ETDEWEB)

    Perri, Pasquale R.; Cooney, John; Fong, Bill; Julander, Dale; Marasigan, Aleks; Morea, Mike; Piceno, Deborah; Stone, Bill; Emanuele, Mark; Sheffield, Jon; Wells, Jeff; Westbrook, Bill; Karnes, Karl; Pearson, Matt; Heisler, Stuart

    2000-04-24

    The primary objective of this project was to conduct advanced reservoir characterization and modeling studies in the Antelope Shale of the Bureau Vista Hills Field. Work was subdivided into two phases or budget periods. The first phase of the project focused on a variety of advanced reservoir characterization techniques to determine the production characteristics of the Antelope Shale reservoir. Reservoir models based on the results of the characterization work would then be used to evaluate how the reservoir would respond to enhanced oil recovery (EOR) processes such as of CO2 flooding. The second phase of the project would be to implement and evaluate a CO2 in the Buena Vista Hills Field. A successful project would demonstrate the economic viability and widespread applicability of CO2 flooding in siliceous shale reservoirs of the San Joaquin Valley.

  5. Removal of Trace Elements by Cupric Oxide Nanoparticles from Uranium In Situ Recovery Bleed Water and Its Effect on Cell Viability

    Science.gov (United States)

    Schilz, Jodi R.; Reddy, K. J.; Nair, Sreejayan; Johnson, Thomas E.; Tjalkens, Ronald B.; Krueger, Kem P.; Clark, Suzanne

    2015-01-01

    In situ recovery (ISR) is the predominant method of uranium extraction in the United States. During ISR, uranium is leached from an ore body and extracted through ion exchange. The resultant production bleed water (PBW) contains contaminants such as arsenic and other heavy metals. Samples of PBW from an active ISR uranium facility were treated with cupric oxide nanoparticles (CuO-NPs). CuO-NP treatment of PBW reduced priority contaminants, including arsenic, selenium, uranium, and vanadium. Untreated and CuO-NP treated PBW was used as the liquid component of the cell growth media and changes in viability were determined by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay in human embryonic kidney (HEK 293) and human hepatocellular carcinoma (Hep G2) cells. CuO-NP treatment was associated with improved HEK and HEP cell viability. Limitations of this method include dilution of the PBW by growth media components and during osmolality adjustment as well as necessary pH adjustment. This method is limited in its wider context due to dilution effects and changes in the pH of the PBW which is traditionally slightly acidic however; this method could have a broader use assessing CuO-NP treatment in more neutral waters. PMID:26132311

  6. Bacterial viability differentially influences the immunomodulatory capabilities of potential host-derived probiotics in the intestinal epithelial cells of Atlantic cod Gadus morhua.

    Science.gov (United States)

    Lazado, C C; Caipang, C M A

    2014-04-01

    This study explored the effect of heat inactivation on the immunomodulatory capabilities of two potential host-derived probiotics (GP21 and GP12) on the intestinal epithelial cells (IEPC) derived from Atlantic cod. The cells were isolated from the four segments of the gut, namely anterior intestine (AI), mid-intestine (MI), posterior intestine (PI) and rectum (RC). The IEPC cultures were exposed to live or heat-inactivated form of GP21 and GP12 for 24 h. The expression profiles of bacterial defence genes and cytokine genes in the probiotics-exposed IEPCs showed differential patterns. Heat inactivation did not drastically affect the immunomodulatory properties of the probiotics, and this was explicitly typified by the stimulated expression of g-type lysozyme, hepcidin, transferrin and metallothionein in both forms of the bacteria. There was no distinct expression pattern of the interleukin genes during bacterial exposure. This was in contrast to the chemokines where the expression of these genes in IEPCs was down-regulated upon exposure to the heat-inactivated probiotics. Although heat inactivation did not drastically affect the immunomodulatory capabilities of the probiotics, the live form elicited higher immune responses in the IEPCs in most cases. This study showed that bacterial viability was a contributing influence, but not a major limiting factor on the immune-related functions of the host-derived probiotics in vitro. GP21 and GP12 are beneficial host-derived bacteria and could be utilized as candidate probiotics in cod aquaculture. © 2013 The Society for Applied Microbiology.

  7. Cell proliferation, viability, and in vitro differentiation of equine mesenchymal stem cells seeded on bacterial cellulose hydrogel scaffolds

    Energy Technology Data Exchange (ETDEWEB)

    Favi, Pelagie M.; Benson, Roberto S. [Department of Materials Science and Engineering, College of Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Neilsen, Nancy R. [Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN 37996 (United States); Hammonds, Ryan L. [Department of Materials Science and Engineering, College of Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Bates, Cassandra C. [Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN 37996 (United States); Stephens, Christopher P. [Department of Surgery, Graduate School of Medicine, University of Tennessee, Knoxville, TN 37996 (United States); Center for Materials Processing, University of Tennessee, Knoxville, TN 37996 (United States); Dhar, Madhu S., E-mail: mdhar@utk.edu [Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN 37996 (United States)

    2013-05-01

    The culture of multipotent mesenchymal stem cells on natural biopolymers holds great promise for treatments of connective tissue disorders such as osteoarthritis. The safety and performance of such therapies relies on the systematic in vitro evaluation of the developed stem cell-biomaterial constructs prior to in vivo implantation. This study evaluates bacterial cellulose (BC), a biocompatible natural polymer, as a scaffold for equine-derived bone marrow mesenchymal stem cells (EqMSCs) for application in bone and cartilage tissue engineering. An equine model was chosen due to similarities in size, load and types of joint injuries suffered by horses and humans. Lyophilized and critical point dried BC hydrogel scaffolds were characterized using scanning electron microscopy (SEM) to confirm nanostructure morphology which demonstrated that critical point drying induces fibre bundling unlike lyophilisation. EqMSCs positively expressed the undifferentiated pluripotent mesenchymal stem cell surface markers CD44 and CD90. The BC scaffolds were shown to be cytocompatible, supporting cellular adhesion and proliferation, and allowed for osteogenic and chondrogenic differentiation of EqMSCs. The cells seeded on the BC hydrogel were shown to be viable and metabolically active. These findings demonstrate that the combination of a BC hydrogel and EqMSCs are promising constructs for musculoskeletal tissue engineering applications. - Highlights: ► Critical point drying induces fibre bundling unlike lyophilisation. ► Cells positively expressed undifferentiated pluripotent stem cell markers. ► BCs were cytocompatible, supported cell adhesion, proliferation and differentiation ► Cells seeded on BC scaffolds were viable and metabolically active. ► Findings demonstrate that BC and EqMSCs are promising tissue engineered constructs.

  8. Commensal Bacteria-Induced Inflammasome Activation in Mouse and Human Macrophages Is Dependent on Potassium Efflux but Does Not Require Phagocytosis or Bacterial Viability.

    Directory of Open Access Journals (Sweden)

    Kejie Chen

    Full Text Available Gut commensal bacteria contribute to the pathogenesis of inflammatory bowel disease, in part by activating the inflammasome and inducing secretion of interleukin-1ß (IL-1ß. Although much has been learned about inflammasome activation by bacterial pathogens, little is known about how commensals carry out this process. Accordingly, we investigated the mechanism of inflammasome activation by representative commensal bacteria, the Gram-positive Bifidobacterium longum subspecies infantis and the Gram-negative Bacteroides fragilis. B. infantis and B. fragilis induced IL-1ß secretion by primary mouse bone marrow-derived macrophages after overnight incubation. IL-1ß secretion also occurred in response to heat-killed bacteria and was only partly reduced when phagocytosis was inhibited with cytochalasin D. Similar results were obtained with a wild-type immortalized mouse macrophage cell line but neither B. infantis nor B. fragilis induced IL-1ß secretion in a mouse macrophage line lacking the nucleotide-binding/leucine-rich repeat pyrin domain containing 3 (NLRP3 inflammasome. IL-1ß secretion in response to B. infantis and B. fragilis was significantly reduced when the wild-type macrophage line was treated with inhibitors of potassium efflux, either increased extracellular potassium concentrations or the channel blocker ruthenium red. Both live and heat-killed B. infantis and B. fragilis also induced IL-1ß secretion by human macrophages (differentiated THP-1 cells or primary monocyte-derived macrophages after 4 hours of infection, and the secretion was inhibited by raised extracellular potassium and ruthenium red but not by cytochalasin D. Taken together, our findings indicate that the commensal bacteria B. infantis and B. fragilis activate the NLRP3 inflammasome in both mouse and human macrophages by a mechanism that involves potassium efflux and that does not require bacterial viability or phagocytosis.

  9. Commensal Bacteria-Induced Inflammasome Activation in Mouse and Human Macrophages Is Dependent on Potassium Efflux but Does Not Require Phagocytosis or Bacterial Viability.

    Science.gov (United States)

    Chen, Kejie; Shanmugam, Nanda Kumar N; Pazos, Michael A; Hurley, Bryan P; Cherayil, Bobby J

    2016-01-01

    Gut commensal bacteria contribute to the pathogenesis of inflammatory bowel disease, in part by activating the inflammasome and inducing secretion of interleukin-1ß (IL-1ß). Although much has been learned about inflammasome activation by bacterial pathogens, little is known about how commensals carry out this process. Accordingly, we investigated the mechanism of inflammasome activation by representative commensal bacteria, the Gram-positive Bifidobacterium longum subspecies infantis and the Gram-negative Bacteroides fragilis. B. infantis and B. fragilis induced IL-1ß secretion by primary mouse bone marrow-derived macrophages after overnight incubation. IL-1ß secretion also occurred in response to heat-killed bacteria and was only partly reduced when phagocytosis was inhibited with cytochalasin D. Similar results were obtained with a wild-type immortalized mouse macrophage cell line but neither B. infantis nor B. fragilis induced IL-1ß secretion in a mouse macrophage line lacking the nucleotide-binding/leucine-rich repeat pyrin domain containing 3 (NLRP3) inflammasome. IL-1ß secretion in response to B. infantis and B. fragilis was significantly reduced when the wild-type macrophage line was treated with inhibitors of potassium efflux, either increased extracellular potassium concentrations or the channel blocker ruthenium red. Both live and heat-killed B. infantis and B. fragilis also induced IL-1ß secretion by human macrophages (differentiated THP-1 cells or primary monocyte-derived macrophages) after 4 hours of infection, and the secretion was inhibited by raised extracellular potassium and ruthenium red but not by cytochalasin D. Taken together, our findings indicate that the commensal bacteria B. infantis and B. fragilis activate the NLRP3 inflammasome in both mouse and human macrophages by a mechanism that involves potassium efflux and that does not require bacterial viability or phagocytosis.

  10. Abundance, viability and culturability of Antarctic bacteria

    Digital Repository Service at National Institute of Oceanography (India)

    LokaBharathi, P.A.; DeSouza, M.J.B.D.; Nair, S.; Chandramohan, D.

    The viability of total number of bacteria decide the mineralisation rate in any ecosystem and ultimately the fertility of the region. This study aims at establishing the extent of viability in the standing stock of the Antarctic bacterial population...

  11. Viability Theory

    CERN Document Server

    Aubin, Jean-Pierre; Saint-Pierre, Patrick

    2011-01-01

    Viability theory designs and develops mathematical and algorithmic methods for investigating the adaptation to viability constraints of evolutions governed by complex systems under uncertainty that are found in many domains involving living beings, from biological evolution to economics, from environmental sciences to financial markets, from control theory and robotics to cognitive sciences. It involves interdisciplinary investigations spanning fields that have traditionally developed in isolation. The purpose of this book is to present an initiation to applications of viability theory, explai

  12. Validation of a Nylon-Flocked-Swab Protocol for Efficient Recovery of Bacterial Spores from Smooth and Rough Surfaces▿

    Science.gov (United States)

    Probst, Alexander; Facius, Rainer; Wirth, Reinhard; Moissl-Eichinger, Christine

    2010-01-01

    In order to meet planetary-protection requirements, culturable bacterial spore loads are measured representatively for the total microbial contamination of spacecraft. However, the National Aeronautics and Space Administration's (NASA's) cotton swab protocols for spore load determination have not changed for decades. To determine whether a more efficient alternative was available, a novel swab was evaluated for recovery of different Bacillus atrophaeus spore concentrations on stainless steel and other surfaces. Two protocols for the nylon-flocked swab (NFS) were validated and compared to the present NASA standard protocol. The results indicate that the novel swab protocols recover 3- to 4-fold more (45.4% and 49.0% recovery efficiency) B. atrophaeus spores than the NASA standard method (13.2%). Moreover, the nylon-flocked-swab protocols were superior in recovery efficiency for spores of seven different Bacillus species, including Bacillus anthracis Sterne (recovery efficiency, 20%). The recovery efficiencies for B. atrophaeus spores from different surfaces showed a variation from 5.9 to 62.0%, depending on the roughness of the surface analyzed. Direct inoculation of the swab resulted in a recovery rate of about 80%, consistent with the results of scanning electron micrographs that allowed detailed comparisons of the two swab types. The results of this investigation will significantly contribute to the cleanliness control of future life detection missions and will provide significant improvement in detection of B. anthracis contamination for law enforcement and security efforts. PMID:20543054

  13. Bacterial recovery using sonication versus swabbing of titanium and stainless steel implants inoculated with Staphylococcus pseudintermedius or Pseudomonas aeruginosa.

    Science.gov (United States)

    Keeshen, Thomas; Case, J Brad; Wellehan, James F; Dujowich, Mauricio

    2017-09-12

    To evaluate the use of sonication to improve recovery of bacteria from metal discs infected with bacteria commonly associated with implant infections in veterinary medicine. In vitro study in which sterile titanium (Ti6Al4V) and stainless steel (AIS1316-L) discs were incubated with either Staphylococcus pseudintermedius or Pseudomonas aeruginosa for 24 hours. The following three groups were compared: 1) the sonication group involved immersing the discs in sterile saline and sonicating for five minutes; 2) the sham group was considered a negative control in which the discs were immersed in saline for five minutes without sonication; and 3) the swab group involved systematically swabbing the implant with a sterile culturette. All samples were plated on blood agar and incubated for 24 hours. Colonies were then counted and compared. For both species of bacteria, there was a significant increase in bacterial colonies isolated using sonication compared to the other two study groups (p = 0.0001). No differences in bacterial growth were found between the two types of metal implants. There was a significant increase in bacterial colony counts for S. pseudintermedius when comparing the swab group versus the sham group, but this was not significant for P. aeruginosa. Sonication significantly improves recovery of bacteria commonly associated with veterinary implant-associated surgical site infections compared to swabbing of implants in vitro. A prospective clinical evaluation is indicated to determine the in vivo efficacy of sonication in veterinary patients.

  14. Assessment of viability of the nematode eggs ([i]Ascaris[/i], [i]Toxocara[/i], [i]Trichuris[/i] in sewage sludge with the use of LIVE/DEAD Bacterial Viability Kit

    Directory of Open Access Journals (Sweden)

    Joanna Dąbrowska

    2014-03-01

    Full Text Available Sewage sludges from wastewater treatment plants may contain live parasite eggs, which can be a source of humans and animals infection. According to the current rules, parasitological examination includes detection of the [i]Ascaris [/i]spp., [i]Trichuris [/i]spp. [i]and Toxocara [/i]spp. eggs and estimation of their viability. The viability assessment based only on the incubation and observation of isolated egg is long and imprecise. The aim of this study was to develop sensitive and less labourintensive methods for assessing viability of [i]Ascaris [/i]spp[i]., Toxocara [/i]spp[i]. and Trichuris [/i]spp[i].[/i] eggs in sewage sludge. For this purpose, LIVE/DEAD Kit was used. Firstly, the possibility of distinguishing between live and dead eggs in water was assessed. Secondly, an appropriate amount of dyeing mixture needed to distinguish the live and dead eggs in the sewage sludge was determined using experimentally enriched samples and naturally contaminated samples of sludge. Eggs were isolated from the samples by own method which was a combination of flotation and sedimentation, preceded by a long mixing. After the last stage of the procedure, sediment containing the eggs of parasites was stained by LIVE/DEAD kit according to the manufacturer instructions, but with the use of different variants of dyes mixture concentration. The investigation showed that live and dead eggs of these three parasites could be differed by this method with the use of proper concentration of dyes. Live eggs were stained in green ([i]Ascaris and Trichuris[/i] and green-blue ([i]Toxocara[/i]. However, all types of dead eggs were red coloured. The study demonstrated that after some modifications (resulted from the nature of the samples the LIVE/DEAD kit is useful for assessing the viability of [i]Toxocara[/i], [i]Ascaris[/i] and [i]Trichuris[/i] eggs occurring in the sludge.

  15. Culture Media and Individual Hosts Affect the Recovery of Culturable Bacterial Diversity from Amphibian Skin.

    Science.gov (United States)

    Medina, Daniel; Walke, Jenifer B; Gajewski, Zachary; Becker, Matthew H; Swartwout, Meredith C; Belden, Lisa K

    2017-01-01

    One current challenge in microbial ecology is elucidating the functional roles of the large diversity of free-living and host-associated bacteria identified by culture-independent molecular methods. Importantly, the characterization of this immense bacterial diversity will likely require merging data from culture-independent approaches with work on bacterial isolates in culture. Amphibian skin bacterial communities have become a recent focus of work in host-associated microbial systems due to the potential role of these skin bacteria in host defense against the pathogenic fungus Batrachochytrium dendrobatidis (Bd), which is associated with global amphibian population declines and extinctions. As there is evidence that some skin bacteria may inhibit growth of Bd and prevent infection in some cases, there is interest in using these bacteria as probiotic therapy for conservation of at-risk amphibians. In this study, we used skin swabs from American toads ( Anaxyrus americanus ) to: (1) assess the diversity and community structure of culturable amphibian skin bacteria grown on high and low nutrient culture media, (2) determine which culture media recover the highest proportion of the total skin bacterial community of individual toads relative to culture-independent data, and (3) assess whether the plated communities from the distinct media types vary in their ability to inhibit Bd growth in in-vitro assays. Overall, we found that culture media with low nutrient concentrations facilitated the growth of more diverse bacterial taxa and grew distinct communities relative to media with higher nutrient concentrations. Use of low nutrient media also resulted in culturing proportionally more of the bacterial diversity on individual toads relative to the overall community defined using culture-independent methods. However, while there were differences in diversity among media types, the variation among individual hosts was greater than variation among media types, suggesting

  16. The Effect of Specific Conditions on Cu, Ni, Zn and Al Recovery from PCBS Waste Using Acidophilic Bacterial Strains

    Directory of Open Access Journals (Sweden)

    Mrážiková A.

    2016-03-01

    Full Text Available The objective of this work was to evaluate the influence of static, stirring and shaking conditions on copper, zinc, nickel and aluminium dissolution from printed circuit boards (PCBs using the mixed acidophilic bacterial culture of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans. The results revealed that static conditions were the most effective in zinc and aluminium dissolution. Zinc was removed almost completely under static conditions, whereas maximum of nickel dissolution was reached under the stirring conditions. The highest copper recovery (36% was reached under stirring conditions. The shaking conditions appeared to be the least suitable. The relative importance of these systems for the bioleaching of copper and nickel decreased in the order: stirring, static conditions, shaking.

  17. Functioned silver nanoparticle loaded activated carbon for the recovery of bioactive molecule from bacterial fermenter for its bactericidal activity

    Science.gov (United States)

    Arivizhivendhan, Villalan; Mahesh, Mannacharaju; Boopathy, Ramasamy; Karthikeyan, Sekar; Mary, Rathanasamy Regina; Sekaran, Ganesan

    2018-01-01

    A novel continuous production and extraction of bacterial bioactive prodigiosin (PG) from fermented using silver nanoparticle impregnated functioned activated carbon composite is proposed for cost-effective and ecofriendly microbial technique. Hence, in this investigation silver nanoparticle was impregnated onto functioned activated carbon ([AC]F) as a support matrix and to enable the separation of PG conjugated silver nanoparticle from the fermented medium. A laboratory scale experiment was carried out to evaluate the continuous production and recovery of PG using [AC@Ag]F. Ag nanoparticle impregnated [AC]F ([AC@Ag]F) characterized by FT-IR, XRD, TGA, DSC and SEM. Instrumental analyses confirmed that Ag nanoparticles significantly impregnated on AC through the functionalization of AC with diethanolamine and it enhances the binding capacity between AC and Ag. The various process parameters, such as contact time, pH, and mass of [AC@Ag]F, were statistically optimized for the recovery of PG using Response Surface Methodology (RSM). The maximum extraction of PG in [AC@Ag]F was found to be 16.2 ± 0.2 mg g-1, its twofold higher than [AC]F. Further, PG conjugated [AC@Ag]F and ([AC@Ag]F-PG) were checked for the growth inhibition of gram negative and gram positive bacteria without formation of biofilm upto 96 h. Hence, the developed matrix could be eco-friendly, viable and lower energy consumption step for separation of the bacterial bioactive PG from fermented broth. In additionally, [AC@Ag]F-PG was used as an antifouling matrix without formation of biofilm.

  18. The effect of non-standard heat treatment of sheep's milk on physico-chemical properties, sensory characteristics, and the bacterial viability of classical and probiotic yogurt.

    Science.gov (United States)

    Zamberlin, Šimun; Samaržija, Dubravka

    2017-06-15

    Classical and probiotic set yogurt were made using non-standard heat treatment of sheep's milk at 60°C/5min. Physico-chemical properties, sensory characteristics, and the viability of bacteria that originated from cultures in classical and probiotic yogurt were analysed during 21days of storage at 4°C. For the production of yogurt, a standard yogurt culture and a probiotic strain Lactobacillus rhamnosus GG were used. At the end of storage time of the classical and probiotic yogurt the totals of non-denatured whey proteins were 92.31 and 91.03%. The viability of yogurt culture bacteria and Lactobacillus rhamnosus GG were higher than 10 6 cfu/g. The total sensory score (maximum - 20) was 18.49 for the classical and 18.53 for the probiotic. In nutritional and functional terms it is possible to produce classical and probiotic sheep's milk yogurt by using a non-standard temperature of heat treatment with a shelf life of 21days. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Viability of bacteria in peatlands

    Science.gov (United States)

    Bogdanova, O. Yu.; Golovchenko, A. V.; Lysak, L. V.; Glukhova, T. V.; Zvyagintsev, D. G.

    2014-04-01

    The viability of bacteria in oligotrofic bogs and fens was determined by the luminescent microscopy method with the help of a two-component fluorescent dye (L7012 LIVE/DEAD). Living bacterial cells were found in the entire peat profiles. Their portion was maximal (up to 60%) in the upper layers and did not exceed 25% in the lower layers. The portion of dead bacterial cells varied from 3 to 19%, and dormant cells constituted 25 to 95% of the total number of bacterial cells. The numbers of dormant cells increased down the profiles irrespectively of the peat type. The portion of nanoforms did not exceed 5% of the total. The cells of the nanoforms, unlike the bacteria of typical sizes, were characterized by their high viability (93-98%).

  20. Strategies for the recovery of active proteins through refolding of bacterial inclusion body proteins

    Directory of Open Access Journals (Sweden)

    Rinas Ursula

    2004-09-01

    Full Text Available Abstract Recent advances in generating active proteins through refolding of bacterial inclusion body proteins are summarized in conjunction with a short overview on inclusion body isolation and solubilization procedures. In particular, the pros and cons of well-established robust refolding techniques such as direct dilution as well as less common ones such as diafiltration or chromatographic processes including size exclusion chromatography, matrix- or affinity-based techniques and hydrophobic interaction chromatography are discussed. Moreover, the effect of physical variables (temperature and pressure as well as the presence of buffer additives on the refolding process is elucidated. In particular, the impact of protein stabilizing or destabilizing low- and high-molecular weight additives as well as micellar and liposomal systems on protein refolding is illustrated. Also, techniques mimicking the principles encountered during in vivo folding such as processes based on natural and artificial chaperones and propeptide-assisted protein refolding are presented. Moreover, the special requirements for the generation of disulfide bonded proteins and the specific problems and solutions, which arise during process integration are discussed. Finally, the different strategies are examined regarding their applicability for large-scale production processes or high-throughput screening procedures.

  1. The effect of uranium on bacterial viability and cell surface morphology using atomic force microscopy in the presence of bicarbonate ions

    Energy Technology Data Exchange (ETDEWEB)

    Sepulveda-Medina, Paola; Katsenovich, Yelena; Musaramthota, Vishal; Lee, Michelle; Lee, Brady; Dua, Rupak; Lagos, Leonel

    2015-06-01

    Nuclear production facilities during the Cold War have caused liquid waste to leak and soak into the ground creating multiple radionuclide plumes. The Arthrobacter bacteria are one of the most common groups in soils and are found in large numbers in subsurface environments contaminated with radionuclides. This study experimentally analyzed changes on the bacteria surface after uranium exposure and evaluated the effect of bicarbonate ions on U(VI) toxicity of a less uranium tolerant Arthrobacter strain, G968, by investigating changes in adhesion forces and cells dimensions via atomic force microscopy (AFM). AFM and viability studies showed that samples containing bicarbonate are able to acclimate and withstand uranium toxicity. Samples containing no bicarbonate exhibited deformed surfaces and a low height profile, which might be an indication that the cells are not alive.

  2. In-vitro experimental evaluation of skin-to-surface recovery of four bacterial species by antibacterial and non-antibacterial medical examination gloves.

    Science.gov (United States)

    Leitgeb, Johannes; Schuster, Rupert; Eng, Aik-Hwee; Yee, Bit-New; Teh, Yee-Peng; Dosch, Verena; Assadian, Ojan

    2013-10-11

    The number of bacteria recovered from a stainless steel coupon after touching a pigskin substrate with an examination glove coated on its outside with polyhexanide (PHMB), as compared to the number of bacteria recovered in the same manner with non-coated control gloves was evaluated. Suspensions containing 1 × 109 colony-forming units of 4 clinically relevant bacterial species (Enterococcus faecium ATCC #51559; Escherichia coli ATCC #25922; Klebsiella pneumoniae ATCC #4352; and Staphylococcus aureus ATCC #33591) were used to contaminate Gamma-irradiated pigskin substrates. Bacterial recoveries from the pigskin substrate, stainless steel coupons, and each glove swatch were performed. A difference in the bacterial recovery from the stainless steel coupons after touching with coated and uncoated control gloves was measured. For E. faecium, the coated glove showed a reduction of 4.63 log10 cfu recovery, when compared to control gloves. For E. coli, the coated glove showed 5.48 log10 cfu, for K. pneumoniae 5.03 log10 cfu, and for S. aureus 5.72 log10 cfu recovery, when compared to the non-coated control glove. An in-vitro experiment designed to mimic cross-contamination of clinically relevant bacteria in a simulated healthcare setting following glove contact with a contaminated biological surface and cross-transfer to a stainless steel surface has demonstrated that an examination glove coated on its outside surface with PHMB was able to reduce bacterial recovery from a contaminated surface by > 4 log10 cfu, compared to a control non-coated examination glove. These elaborated results may encourage further clinical investigation on the clinical impact of an antibacterial examination glove.

  3. Biogas production from coumarin-rich plants--inhibition by coumarin and recovery by adaptation of the bacterial community.

    Science.gov (United States)

    Popp, Denny; Schrader, Steffi; Kleinsteuber, Sabine; Harms, Hauke; Sträuber, Heike

    2015-09-01

    Plants like sweet clover (Melilotus spp.) are not suitable as fodder for cattle because of harmful effects of the plant secondary metabolite coumarin. As an alternative usage, the applicability of coumarin-rich plants as substrates for biogas production was investigated. When coumarin was added to continuous fermentation processes codigesting grass silage and cow manure, it caused a strong inhibition noticeable as decrease of biogas production by 19% and increase of metabolite concentrations to an organic acids/alkalinity ratio higher than 0.3(gorganic acids) gCaCO3 (-1). Microbial communities of methanogenic archaea were dominated by the genera Methanosarcina (77%) and Methanoculleus (11%). This community composition was not influenced by coumarin addition. The bacterial community analysis unraveled a divergence caused by coumarin addition correlating with the anaerobic degradation of coumarin and the recovery of the biogas process. As a consequence, biogas production resumed similar to the coumarin-free control with a biogas yield of 0.34 LN g(volatile solids) (-1) and at initial metabolite concentrations (∼ 0.2 g(organic acids) gCaCO3 (-1)). Coumarin acts as inhibitor and as substrate during anaerobic digestion. Hence, coumarin-rich plants might be suitable for biogas production, but should only be used after adaptation of the microbial community to coumarin. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Bacterial flora of combat wounds from eastern Ukraine and time-specified changes of bacterial recovery during treatment in Ukrainian military hospital.

    Science.gov (United States)

    Valentine, Kovalchuk P; Viacheslav, Kondratiuk M

    2017-04-07

    Microbiology of modern war wounds is unique for each military conflict. Climatic and geographical features of the theater of war, contemporary warfare as well as wound management affect the microbial flora of wounds. This study was designed to determine time-specific microbial flora of combat wounds of upper and lower extremities obtained during the war in eastern Ukraine. The patients enrolled in study had combat wounds of upper or lower extremities which were treated in the Military Medical Clinical Center of Central Region. The wounds were swab-cultured and measured at each surgical debridement. The recovered microorganisms were identified and their antimicrobial resistance profiles were evaluated by disc diffusion method. Forty-nine patients with battle-field wounds were enrolled in the study from July to November 2014; all patients were male with a mean Injury Severity Score and arrival APACHE II scores of 16.2 ± 10.7 and 7.4 ± 4.2 respectively. Among 128 swab cultures, 100 swab cultures were positive. Swab cultures were obtained from 57 wounds of 49 patients. The results of the test showed that 87.7% of all positive swab cultures contained a single-organism while the rest of the swab-culture results showed polymicrobial growth. Among the isolated microorganisms 65% (76 strains) were Gram-negative rods, 22.2% (26 strains) of Gram-positive cocci, followed by Gram-positive rods (12.8%, 15 strains). We found that epidemiology of wound infection changes with the time after injury. The most common bacterial isolates cultured during the first week were Gram-positive microbes with low pathogenicity. The number of Gram-negative rods increased during the wound healing process. The incidence of Gram-positive microorganisms' growth fell after the first week and increased after third week. During wound healing, bacterial microflora of wounds changes with increasing number of Gram-negative rods with predominance of Acinetobacter species. Predominant microorganisms in

  5. Divergent extremes but convergent recovery of bacterial and archaeal soil communities to an ongoing subterranean coal mine fire.

    Science.gov (United States)

    Lee, Sang-Hoon; Sorensen, Jackson W; Grady, Keara L; Tobin, Tammy C; Shade, Ashley

    2017-06-01

    Press disturbances are stressors that are extended or ongoing relative to the generation times of community members, and, due to their longevity, have the potential to alter communities beyond the possibility of recovery. They also provide key opportunities to investigate ecological resilience and to probe biological limits in the face of prolonged stressors. The underground coal mine fire in Centralia, Pennsylvania has been burning since 1962 and severely alters the overlying surface soils by elevating temperatures and depositing coal combustion pollutants. As the fire burns along the coal seams to disturb new soils, previously disturbed soils return to ambient temperatures, resulting in a chronosequence of fire impact. We used 16S rRNA gene sequencing to examine bacterial and archaeal soil community responses along two active fire fronts in Centralia, and investigated the influences of assembly processes (selection, dispersal and drift) on community outcomes. The hottest soils harbored the most variable and divergent communities, despite their reduced diversity. Recovered soils converged toward similar community structures, demonstrating resilience within 10-20 years and exhibiting near-complete return to reference communities. Measured soil properties (selection), local dispersal, and neutral community assembly models could not explain the divergences of communities observed at temperature extremes, yet beta-null modeling suggested that communities at temperature extremes follow niche-based processes rather than null. We hypothesize that priority effects from responsive seed bank transitions may be key in explaining the multiple equilibria observed among communities at extreme temperatures. These results suggest that soils generally have an intrinsic capacity for robustness to varied disturbances, even to press disturbances considered to be 'extreme', compounded, or incongruent with natural conditions.

  6. Assessment of myocardial viability using PET

    International Nuclear Information System (INIS)

    Yoon, Seok Nam

    2005-01-01

    The potential for recovery of left ventricular dysfunction after myocardial revascularization represents a practical clinical definition for myocardial viability. The evaluation of viable myocardium in patients with severe global left ventricular dysfunction due to coronary artery disease and with regional dysfunction after acute myocardial infarction is an important issue whether left ventricular dysfunction may be reversible or irreversible after therapy. If the dysfunction is due to stunning or hibernation, functional improvement is observed. But stunned myocardium may recover of dysfunction with no revascularization. Hibernation is chronic process due to chronic reduction in the resting myocardial blood flow. There are two types of myocardial hibernation; 'functional hibernation' with preserved contractile reserve and 'structural hibernation' without contractile reserve in segments with preserved glucose metabolism. This review focus on the application of F-18 FDG and other radionuclides to evaluate myocardial viability. In addition the factors influencing predictive value of FDG imaging for evaluating viability and the different criteria for viability are also reviewed

  7. Establishing Guidelines to Retain Viability of Probiotics during Spray Drying

    NARCIS (Netherlands)

    Perdana, J.A.; Fox, M.B.; Boom, R.M.; Schutyser, M.A.I.

    2015-01-01

    We present the application of a model-based approach to map processing conditions suitable to spray dry probiotics with minimal viability loss. The approach combines the drying history and bacterial inactivation kinetics to predict the retention of viability after drying. The approach was used to

  8. Establishing guidelines to retain viability of probiotics during spray drying

    NARCIS (Netherlands)

    Perdana, J.A.; Fox, M.B.; Boom, R.M.; Schutyser, M.A.I.

    2014-01-01

    We present a model-based approach to map processing conditions suitable to spray dry probiotics with minimal viability loss. The approach combines the drying history and bacterial inactivation kinetics to predict the retention of viability after drying. The approach was used to systematically assess

  9. Isolation, identification and characterization of Bacillus amyloliquefaciens BZ-6, a bacterial isolate for enhancing oil recovery from oily sludge.

    Science.gov (United States)

    Liu, Wuxing; Wang, Xiaobing; Wu, Longhua; Chen, Mengfang; Tu, Chen; Luo, Yongming; Christie, Peter

    2012-06-01

    Over 100 biosurfactant-producing microorganisms were isolated from oily sludge and petroleum-contaminated soil from Shengli oil field in north China. Sixteen of the bacterial isolates produced biosurfactants and reduced the surface tension of the growth medium from 71 to identification, isolate BZ-6 was identified as Bacillus amyloliquefaciens. The biosurfactant produced by isolate BZ-6 was purified and analyzed by high performance liquid chromatography-electrospray ionization tandem mass spectrometry. There were four ion peaks representing four different fengycin A homologues. Copyright © 2012. Published by Elsevier Ltd.

  10. Puget Sound steelhead life cycle model analyses - Population Viability Analysis

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This research was initiated by the Puget Sound Steelhead Technical Recovery Team to develop viability criteria for threatened Puget Sound steelhead and to support...

  11. The Survival and Recovery of Irradiated Bacterial Spores as Affected by Population Density and Some External Factors

    International Nuclear Information System (INIS)

    Farkas, J.; Kiss, I.; Andrássy, E.

    1967-01-01

    The radiation resistance of Bacillus cereus spores as affected by the pH-value and cell density of the irradiated spore suspensions was investigated. The portions of the survival curves of suspensions of 10 8 , 4 x 10 3 and 5 x 10 1 per millilitre viable cell counts, respectively, were compared for a three-orders-of-magnitude decrease in viable cell count. It was established that the initial cell density did not affect radiation resistance of spores. Radiation resistance as affected by pH-value in the range of 3 to 8 was investigated. In the range of pH 5 to 8, the radiation resistance of B. cereus spores was not affected. By lowering the pH-value to below 5, the radiation resistance decreased below that observed in the neutral region. The colony-forming capacity of B. cereus, B. coagulans and B. pumilus as a function of the pH-value in the nutrient medium, and the pH-sensitivity of bacterial spores as affected by radiation, were also investigated. It was established that irradiation increased the pH-sensitivity of surviving bacterial spores in all three strains. The initial phase of spore germination (the phase accompanied by decrease of refractivity of the spores) and the division stage of vegetative cells proved to be the most sensitive to the value of the hydrogen ion concentration. (author)

  12. Normoxic Recovery Mimicking Treatment of Sleep Apnea Does Not Reverse Intermittent Hypoxia-Induced Bacterial Dysbiosis and Low-Grade Endotoxemia in Mice.

    Science.gov (United States)

    Moreno-Indias, Isabel; Torres, Marta; Sanchez-Alcoholado, Lidia; Cardona, Fernando; Almendros, Isaac; Gozal, David; Montserrat, Josep M; Queipo-Ortuño, Maria I; Farré, Ramon

    2016-10-01

    Intermittent hypoxia (IH) mimicking obstructive sleep apnea (OSA) significantly modifies gut microbiota in mice. However, whether these IH-induced gut microbiome changes are reversible after restoring normal oxygenation (the equivalent of effective OSA therapy) is unknown. The aim of this study was to investigate gut microbiota composition and circulating endotoxemia after a post-IH normoxic period in a mouse model of OSA. Ten mice were subjected to IH (40 sec 21% O2-20 sec 5% O2) for 6 h/day for 6 w and 10 mice breathing normoxic air (NM) were used as controls. After exposures, both groups were subjected to 6 w in normoxia. Microbiome composition of fecal samples was determined by 16S ribosomal RNA (rRNA) pyrosequencing. Bioinformatic analysis was performed by Quantitative Insights into Microbial Ecology. Plasma lipopolysaccharide (LPS) levels were measured by endotoxin assay. After normoxic recovery, the Chao and Shannon indices of each group suggested similar bacterial richness and diversity. 16S rRNA pyrosequencing analysis showed that IH-exposed mice had a significant decrease in the abundance of Bacteroidetes and a significant increase of Firmicutes and Deferribacteres compared to the NM group. After normoxic recovery, circulating LPS concentrations were higher in the IH group (P < 0.009). Moreover, the IH group showed a negative and significant correlation between the abundance of Lactobacillus and Ruminococcus and significant positive correlations between the abundance of Mucispirillum and Desulfovibrio and plasma LPS levels, respectively. Even after prolonged normoxic recovery after IH exposures, gut microbiota and circulating endotoxemia remain negatively altered, suggesting that potential benefits of OSA treatment for reversing OSA-induced changes in gut microbiota may either require a longer period or alternative interventions. © 2016 Associated Professional Sleep Societies, LLC.

  13. Multifractal resilience and viability

    Science.gov (United States)

    Tchiguirinskaia, I.; Schertzer, D. J. M.

    2017-12-01

    The term resilience has become extremely fashionable and there had been many attempts to provide operational definition and in fact metrics going beyond a set of more or less ad-hoc indicators. The viability theory (Aubin and Saint-Pierre, 2011) have been used to give a rather precise mathematical definition of resilience (Deffuant and Gilbert, 2011). However, it does not grasp the multiscale nature of resilience that is rather fundamental as particularly stressed by Folke et al (2010). In this communication, we first recall a preliminary attempt (Tchiguirinskaia et al., 2014) to define multifractal resilience with the help of the maximal probable singularity. Then we extend this multifractal approach to the capture basin of the viability, therefore the resilient basin. Aubin, J P, A. Bayen, and P Saint-Pierre (2011). Viability Theory. New Directions. Springer, Berlin,. Deffuant, G. and Gilbert, N. (eds) (2011) Viability and Resilience of Complex Systems. Springer Berlin.Folke, C., S R Carpenter, B Walker, M Sheffer, T Chapin, and J Rockstroem (2010). Resilience thinking: integrating re- silience, adaptability and transformability. Ecology and So- ciety, 14(4):20, Tchiguirinskaia,I., D. Schertzer, , A. Giangola-Murzyn and T. C. Hoang (2014). Multiscale resilience metrics to assess flood. Proceedings of ICCSA 2014, Normandie University, Le Havre, France -.

  14. Viability, invariance and applications

    CERN Document Server

    Carja, Ovidiu; Vrabie, Ioan I

    2007-01-01

    The book is an almost self-contained presentation of the most important concepts and results in viability and invariance. The viability of a set K with respect to a given function (or multi-function) F, defined on it, describes the property that, for each initial data in K, the differential equation (or inclusion) driven by that function or multi-function) to have at least one solution. The invariance of a set K with respect to a function (or multi-function) F, defined on a larger set D, is that property which says that each solution of the differential equation (or inclusion) driven by F and issuing in K remains in K, at least for a short time.The book includes the most important necessary and sufficient conditions for viability starting with Nagumo's Viability Theorem for ordinary differential equations with continuous right-hand sides and continuing with the corresponding extensions either to differential inclusions or to semilinear or even fully nonlinear evolution equations, systems and inclusions. In th...

  15. Viability and resilience of complex systems concepts, methods and case studies from ecology and society

    CERN Document Server

    Deffuant, Guillaume

    2011-01-01

    One common characteristic of a complex system is its ability to withstand major disturbances and the capacity to rebuild itself. Understanding how such systems demonstrate resilience by absorbing or recovering from major external perturbations requires both quantitative foundations and a multidisciplinary view of the topic. This book demonstrates how new methods can be used to identify the actions favouring the recovery from perturbations on a variety of examples including the dynamics of bacterial biofilms, grassland savannahs, language competition and Internet social networking sites. The reader is taken through an introduction to the idea of resilience and viability and shown the mathematical basis of the techniques used to analyse systems. The idea of individual or agent-based modelling of complex systems is introduced and related to analytically tractable approximations of such models. A set of case studies illustrates the use of the techniques in real applications, and the final section describes how on...

  16. Evaluation of different cryoprotective agents in maintenance of viability of Helicobacter pylori in stock culture media

    Directory of Open Access Journals (Sweden)

    Daryoush Davoudi Oskouei

    2010-12-01

    Full Text Available Four different cryoprotective supplemented stock media were evaluated for maintaining better survival and recovery of H. pylori type strain NCTC 11637 at two different maintenance temperatures of -20°C and -80°C after one month preservation as frozen stocks. The spread plate colony count method was used to investigate the recovery rate of H. pylori from equally inoculated bacterial suspensions in differently prepared stock cultures. After the preservation of H. pylori for one month in different cryoprotectant-supplemented stock media, the recovery rates for -20°C obtained for stock cultures supplemented with dimethyl sulfoxide (DMSO, polyethylene glycol (PEG, glycerol and glycerol+sucrose, as well as controls with and without human serum alone were 7.13, 6.97, 7.93, 7.99, 6.95 and 0.0 log CFU/ml, respectively. Maintenance of bacteria at -80°C gave statistically higher recovery rates compared to preservation at -20°C with the values of 8.55, 8.24, 8.59, 8.66, 8.01 and 0.0 log CFU/ml for these above mentioned stock cultures. The stock cultures supplemented with glycerol+sucrose and glycerol showed the highest recovery rates, 7.99 and 7.93 for -20°C vs. 8.66 and 8.59 for -80°C respectively, which were statistically different from the others. Our study revealed that H. pylori type strain NCTC 11637 could be better preserved at -80°C than -20°C. The best stock media which supported viability or culturability of bacteria were brain heart infusion broth (BHI+glycerol+human serum and BHI+glycerol+sucrose+human serum, where the latter yielded the higher recovery rate.

  17. Assessment of myocardial viability.

    Science.gov (United States)

    Travin, Mark I; Bergmann, Steven R

    2005-01-01

    The prevalence of left ventricular (LV) dysfunction and resultant congestive heart failure is increasing. Patients with this condition are at high risk for cardiac death and usually have significant limitations in their lifestyles. Although there have been advances in medical therapy resulting in improved survival and well being, the best and most definitive therapy, when appropriate, is revascularization. In the setting of coronary artery disease, accounting for approximately two thirds of cases of congestive heart failure, LV dysfunction often is not the result of irreversible scar but rather caused by impairment in function and energy use of still viable-myocytes, with the opportunity for improved function if coronary blood flow is restored. Patients with LV dysfunction who have viable myocardium are the patients at highest risk because of the potential for ischemia but at the same time benefit most from revascularization. It is important to identify viable myocardium in these patients, and radionuclide myocardial scintigraphy is an excellent tool for this. Single-photon emission computed tomography perfusion scintigraphy, whether using thallium-201, Tc-99m sestamibi, or Tc-99m tetrofosmin, in stress and/or rest protocols, has consistently been shown to be an effective modality for identifying myocardial viability and guiding appropriate management. Metabolic imaging with positron emission tomography radiotracers frequently adds additional information and is a powerful tool for predicting which patients will have an improved outcome from revascularization, including some patients referred instead for cardiac transplantation. Other noninvasive modalities, such as stress echocardiography, also facilitate the assessment of myocardial viability, but there are advantages and disadvantages compared with the nuclear techniques. Nuclear imaging appears to require fewer viable cells for detection, resulting in a higher sensitivity but a lower specificity than stress

  18. Advanced reservoir characterization in the Antelope Shale to establish the viability of CO{sub 2} enhanced oil recovery in California`s Monterey Formation siliceous shales. Annual report, February 12, 1996--February 11, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Toronyi, R.M.

    1997-12-01

    The Buena Vista Hills field is located about 25 miles southwest of Bakersfield, in Kern County, California, about two miles north of the city of Taft, and five miles south of the Elk Hills field. The Antelope Shale zone was discovered at the Buena Vista Hills field in 1952, and has since been under primary production. Little research was done to improve the completion techniques during the development phase in the 1950s, so most of the wells are completed with about 1000 ft of slotted liner. The proposed pilot consists of four existing producers on 20 acre spacing with a new 10 acre infill well drilled as the pilot CO{sub 2} injector. Most of the reservoir characterization of the first phase of the project will be performed using data collected in the pilot pattern wells. This is the first annual report of the project. It covers the period February 12, 1996 to February 11, 1997. During this period the Chevron Murvale 653Z-26B well was drilled in Section 26-T31S/R23E in the Buena Vista Hills field, Kern County, California. The Monterey Formation equivalent Brown and Antelope Shales were continuously cored, the zone was logged with several different kinds of wireline logs, and the well was cased to a total depth of 4907 ft. Core recovery was 99.5%. Core analyses that have been performed include Dean Stark porosity, permeability and fluid saturations, field wettability, anelastic strain recovery, spectral core gamma, profile permeametry, and photographic imaging. Wireline log analysis includes mineral-based error minimization (ELAN), NMR T2 processing, and dipole shear wave anisotropy. A shear wave vertical seismic profile was acquired after casing was set and processing is nearly complete.

  19. Advanced reservoir characterization in the Antelope Shale to establish the viability of CO2 enhanced oil recovery in California`s Monterey Formation siliceous shales. Annual report, February 7, 1997--February 6, 1998

    Energy Technology Data Exchange (ETDEWEB)

    Morea, M.F.

    1998-06-01

    The primary objective of this research is to conduct advanced reservoir characterization and modeling studies in the Antelope Shale reservoir. Characterization studies will be used to determine the technical feasibility of implementing a CO{sub 2} enhanced oil recovery project in the antelope Shale in Buena Vista Hills Field. The proposed pilot consists of four existing producers on 20 acre spacing with a new 10 acre infill well drilled as the pilot CO{sub 2} injector. Most of the reservoir characterization during Phase 1 of the project will be performed using data collected in the pilot pattern wells. During this period the following tasks have been completed: laboratory wettability; specific permeability; mercury porosimetry; acoustic anisotropy; rock mechanics analysis; core description; fracture analysis; digital image analysis; mineralogical analysis; hydraulic flow unit analysis; petrographic and confocal thin section analysis; oil geochemical fingerprinting; production logging; carbon/oxygen logging; complex lithologic log analysis; NMR T2 processing; dipole shear wave anisotropy logging; shear wave vertical seismic profile processing; structural mapping; and regional tectonic synthesis. Noteworthy technological successes for this reporting period include: (1) first (ever) high resolution, crosswell reflection images of SJV sediments; (2) first successful application of the TomoSeis acquisition system in siliceous shales; (3) first detailed reservoir characterization of SJV siliceous shales; (4) first mineral based saturation algorithm for SJV siliceous shales, and (5) first CO{sub 2} coreflood experiments for siliceous shale. Preliminary results from the CO{sub 2} coreflood experiments (2,500 psi) suggest that significant oil is being produced from the siliceous shale.

  20. The effects of lactobacillus suppositories in the recovery and recur-rence of bacterial vaginosis: a double-blind randomized clinical trial

    Directory of Open Access Journals (Sweden)

    Soror Roozafzay

    2014-08-01

    Conclusion: The protective effects of lactobacillus in dealing with anaerobic patho-gens as well as the negative impact of metronidazole on lactobacillus of vaginal flora, use of lactobacillus along with metronidazole especially in patients with recurrent infec-tions is recommended. In other words, using lactobacillus with metronidazole for treatment of bacterial vaginosis is more effective than metronidazole alone.

  1. Drying process strongly affects probiotics viability and functionalities.

    Science.gov (United States)

    Iaconelli, Cyril; Lemetais, Guillaume; Kechaou, Noura; Chain, Florian; Bermúdez-Humarán, Luis G; Langella, Philippe; Gervais, Patrick; Beney, Laurent

    2015-11-20

    Probiotic formulations are widely used and are proposed to have a variety of beneficial effects, depending on the probiotic strains present in the product. The impact of drying processes on the viability of probiotics is well documented. However, the impact of these processes on probiotics functionality remains unclear. In this work, we investigated variations in seven different bacterial markers after various desiccation processes. Markers were composed of four different viability evaluation (combining two growth abilities and two cytometric measurements) and in three in vitro functionalities: stimulation of IL-10 and IL-12 production by PBMCs (immunomodulation) and bacterial adhesion to hexadecane. We measured the impact of three drying processes (air-drying, freeze-drying and spray-drying), without the use of protective agents, on three types of probiotic bacteria: Bifidobacterium bifidum, Lactobacillus plantarum and Lactobacillus zeae. Our results show that the bacteria respond differently to the three different drying processes, in terms of viability and functionality. Drying methods produce important variations in bacterial immunomodulation and hydrophobicity, which are correlated. We also show that adherence can be stimulated (air-drying) or inhibited (spray-drying) by drying processes. Results of a multivariate analysis show no direct correlation between bacterial survival and functionality, but do show a correlation between probiotic responses to desiccation-rewetting and the process used to dry the bacteria. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Viability of human adenovirus from hospital fomites.

    Science.gov (United States)

    Ganime, Ana Carolina; Carvalho-Costa, Filipe A; Santos, Marisa; Costa Filho, Rubens; Leite, José Paulo G; Miagostovich, Marize P

    2014-12-01

    The monitoring of environmental microbial contamination in healthcare facilities may be a valuable tool to determine pathogens transmission in those settings; however, such procedure is limited to bacterial indicators. Viruses are found commonly in those environments and are rarely used for these procedures. The aim of this study was to assess distribution and viability of a human DNA virus on fomites in an Adult Intensive Care Unit of a private hospital in Rio de Janeiro, Brazil. Human adenoviruses (HAdV) were investigated in 141 fomites by scraping the surface area and screening by quantitative PCR (qPCR) using TaqMan® System (Carlsbad, CA). Ten positive samples were selected for virus isolation in A549 and/or HEp2c cell lines. A total of 63 samples (44.7%) were positive and presented viral load ranging from 2.48 × 10(1) to 2.1 × 10(3) genomic copies per millilitre (gc/ml). The viability was demonstrated by integrated cell culture/nested-PCR in 5 out of 10 samples. Nucleotide sequencing confirmed all samples as HAdV and characterized one of them as specie B, serotype 3 (HAdV-3). The results indicate the risk of nosocomial transmission via contaminated fomites and point out the use of HAdV as biomarkers of environmental contamination. © 2014 Wiley Periodicals, Inc.

  3. Molecular Viability Testing of UV-Inactivated Bacteria.

    Science.gov (United States)

    Weigel, Kris M; Nguyen, Felicia K; Kearney, Moira R; Meschke, John S; Cangelosi, Gerard A

    2017-05-15

    PCR is effective in detecting bacterial DNA in samples, but it is unable to differentiate viable bacteria from inactivated cells or free DNA fragments. New PCR-based analytical strategies have been developed to address this limitation. Molecular viability testing (MVT) correlates bacterial viability with the ability to rapidly synthesize species-specific rRNA precursors (pre-rRNA) in response to brief nutritional stimulation. Previous studies demonstrated that MVT can assess bacterial inactivation by chlorine, serum, and low-temperature pasteurization. Here, we demonstrate that MVT can detect inactivation of Escherichia coli , Aeromonas hydrophila , and Enterococcus faecalis cells by UV irradiation. Some UV-inactivated E. coli cells transiently retained the ability to synthesize pre-rRNA postirradiation (generating false-positive MVT results), but this activity ceased within 1 h following UV exposure. Viable but transiently undetectable (by culture) E. coli cells were consistently detected by MVT. An alternative viability testing method, viability PCR (vPCR), correlates viability with cell envelope integrity. This method did not distinguish viable bacteria from UV-inactivated bacteria under some conditions, indicating that the inactivated cells retained intact cell envelopes. MVT holds promise as a means to rapidly assess microbial inactivation by UV treatment. IMPORTANCE UV irradiation is increasingly being used to disinfect water, food, and other materials for human use. Confirming the effectiveness of UV disinfection remains a challenging task. In particular, microbiological methods that rely on rapid detection of microbial DNA can yield misleading results, due to the detection of remnant DNA associated with dead microbial cells. This report describes a novel method that rapidly distinguishes living microbial cells from dead microbial cells after UV disinfection. Copyright © 2017 American Society for Microbiology.

  4. Viability of lactobacillus acidophilus in various vaginal tablet formulations

    Directory of Open Access Journals (Sweden)

    Fazeli M.R.

    2006-07-01

    Full Text Available The lactobacilli which are present in vaginal fluids play an important role in prevention of vaginosis and there are considerable interests in formulation of these friendly bacteria into suitable pharmaceutical dosage forms. Formulating these microorganisms for vaginal application is a critical issue as the products should retain viability of lactobacilli during formulation and also storage. The aim of this study was to examine the viability and release of Lactobacillus acidophilus from slow-release vaginal tablets prepared by using six different retarding polymers and from two effervescent tablets prepared by using citric or adipic acid. The Carbomer–based formulations showed high initial viablility compared to those based on HPMC-LV, HPMC-HV, Polycarbophil and SCMC polymers which showed one log decrease in viable cells. All retarding polymers in slow release formulations presented a strong bacterial release at about 2 h except Carbomer polymers which showed to be poor bacterial releasers. Although effervescent formulations produced a quick bacterial release in comparison with polymer based slow-release tablets, they were less stable in cold storage. Due to the strong chelating characteristic of citric acid, the viability was quickly lost for aqueous medium of citric acid in comparison with adipic acid based effervescent tablets.

  5. Probiotic viability - does it matter?

    Science.gov (United States)

    Lahtinen, Sampo J

    2012-01-01

    Probiotics are viable by definition, and viability of probiotics is often considered to be a prerequisite for the health benefits. Indeed, the overwhelming majority of clinical studies in the field have been performed with viable probiotics. However, it has also been speculated that some of the mechanisms behind the probiotic health effects may not be dependent on the viability of the cells and, therefore, is also possible that also non-viable probiotics could have some health benefits. The efficacy of non-viable probiotics has been assessed in a limited number of studies, with varying success. While it is clear that viable probiotics are more effective than non-viable probiotics and that, in many cases, viability is indeed a prerequisite for the health benefit, there are also some cases where it appears that non-viable probiotics could also have beneficial effects on human health.

  6. Bacterial Keratitis

    Science.gov (United States)

    ... Español Eye Health / Eye Health A-Z Bacterial Keratitis Sections What Is Bacterial Keratitis? Bacterial Keratitis Symptoms ... Lens Care Bacterial Keratitis Treatment What Is Bacterial Keratitis? Leer en Español: ¿Qué Es la Queratitis Bacteriana? ...

  7. Comparison of reintroduction and enhancement effects on metapopulation viability

    Science.gov (United States)

    Halsey, Samniqueka J; Bell, Timothy J.; McEachern, A. Kathryn; Pavlovic, Noel B.

    2015-01-01

    Metapopulation viability depends upon a balance of extinction and colonization of local habitats by a species. Mechanisms that can affect this balance include physical characteristics related to natural processes (e.g. succession) as well as anthropogenic actions. Plant restorations can help to produce favorable metapopulation dynamics and consequently increase viability; however, to date no studies confirm this is true. Population viability analysis (PVA) allows for the use of empirical data to generate theoretical future projections in the form of median time to extinction and probability of extinction. In turn, PVAs can inform and aid the development of conservation, recovery, and management plans. Pitcher's thistle (Cirsium pitcheri) is a dune endemic that exhibited metapopulation dynamics. We projected viability of three natural and two restored populations with demographic data spanning 15–23 years to determine the degree the addition of reintroduced population affects metapopulation viability. The models were validated by comparing observed and projected abundances and adjusting parameters associated with demographic and environmental stochasticity to improve model performance. Our chosen model correctly predicted yearly population abundance for 60% of the population-years. Using that model, 50-year projections showed that the addition of reintroductions increases metapopulation viability. The reintroduction that simulated population performance in early-successional habitats had the maximum benefit. In situ enhancements of existing populations proved to be equally effective. This study shows that restorations can facilitate and improve metapopulation viability of species dependent on metapopulation dynamics for survival with long-term persistence of C. pitcheri in Indiana likely to depend on continued active management.

  8. Recovery and screening for antibiotic susceptibility of potential bacterial pathogens from the oral cavity of shark species involved in attacks on humans in Recife, Brazil.

    Science.gov (United States)

    Interaminense, J A; Nascimento, D C O; Ventura, R F; Batista, J E C; Souza, M M C; Hazin, F H V; Pontes-Filho, N T; Lima-Filho, J V

    2010-08-01

    The number of incidents involving sharks and humans at beaches in Recife, on the north-eastern Brazilian coast, is among the highest worldwide. In addition, wound infections in survivors are common; but the nature and risk of the aetiological agents is unknown. In the present study, 81 potential bacterial pathogens were identified in the oral cavity of sharks involved in attacks in Recife, and were subjected to antibiotic susceptibility tests using the standardized disc-diffusion method. The majority were enterobacteria such as Enterobacter spp., Citrobacter spp., Proteus spp., Providencia alcalifaciens, Escherichia coli, Moellerella wisconcensis and Leclercia adecarboxylata. Other Gram-negative bacteria included Vibrio spp., Burkholderia cepacia, Acinetobacter spp. and Pseudomonas spp. In addition, coagulase-positive and coagulase-negative Staphylococcus spp., Enterococcus spp. and Micrococcus spp. were identified, besides Streptococcus spp. from the viridans group. Resistance was especially found in the Proteus mirabilis and Citrobacter freundii, and ranged from 4 to 6 antibiotics out of the 13 tested. Gentamicin and vancomycin were the most effective against Gram-positive cocci strains, whereas levofloxacin was fully inhibitory against Gram-positive and Gram-negative bacteria. These data are discussed in light of a retrospective evaluation of the medical records of three shark victims treated at Restauração Hospital in Recife.

  9. Assessment of Probiotic Viability during Cheddar Cheese Manufacture and Ripening Using Propidium Monoazide-PCR Quantification

    OpenAIRE

    Desfossés-Foucault, Émilie; Dussault-Lepage, Véronique; Le Boucher, Clémentine; Savard, Patricia; LaPointe, Gisèle; Roy, Denis

    2012-01-01

    The use of a suitable food carrier such as cheese could significantly enhance probiotic viability during storage. The main goal of this study was to assess viability of commercial probiotic strains during Cheddar cheesemaking and ripening (four to six months) by comparing the efficiency of microbiological and molecular approaches. Molecular methods such as quantitative PCR (qPCR) allow bacterial quantification, and DNA-blocking molecules such as propidium monoazide (PMA) select only the livin...

  10. Infrared Signatures to Discriminate Viability of Autoclaved Bacillus Spores

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Matthew D.; Valentine, Nancy B.; Johnson, Timothy J.

    2011-10-06

    Optical methods can offer good sensitivity for detecting small amounts of chemicals and biologicals, and as these methods mature, are some of the few techniques that can offer true standoff detection. For detection of biological species, determining the viability is clearly important: Certain species of gram-positive bacteria are capable of forming endospores, specialized structures that arise when living conditions become unfavorable or little growth medium is available, being resistant to many chemicals as well as changes in heat or pH. Such spores can remain dormant from months to years until more favorable conditions arise, resulting in germination back to the vegetative state. This persistence characteristic of bacterial spores allows for contamination of a surface (e.g. food or medical equipment) even after the surface has been nominally cleaned. Bacterial spores have also been used as biological weapons, as in the case with B. anthracis. Thus, rapid analysis to determine a spore's viability in a given environment or after attempts to sterilize a given environment is crucial. The increasing availability of portable spectrometers may provide a key to such rapid onsite analysis. The present study was designed to determine whether infrared spectroscopy may be used to differentiate between viable vs. dead B. subtilis and B. atrophaeus spores. Preliminary results show that the reproducible differences in the IR signatures can be used to identify viable vs. autoclaved (dead) B. subtilis and B. atrophaeus bacterial spores.

  11. Tychastic measure of viability risk

    CERN Document Server

    Aubin, Jean-Pierre; Dordan, Olivier

    2014-01-01

    This book presents a forecasting mechanism of the price intervals for deriving the SCR (solvency capital requirement) eradicating the risk during the exercise period on one hand, and measuring the risk by computing the hedging exit time function associating with smaller investments the date until which the value of the portfolio hedges the liabilities on the other. This information, summarized under the term “tychastic viability measure of risk” is an evolutionary alternative to statistical measures, when dealing with evolutions under uncertainty. The book is written by experts in the field and the target audience primarily comprises research experts and practitioners.

  12. Direct in situ viability assessment of bacteria in probiotic dairy products using viability staining in conjunction with confocal scanning laser microscopy.

    Science.gov (United States)

    Auty, M A; Gardiner, G E; McBrearty, S J; O'Sullivan, E O; Mulvihill, D M; Collins, J K; Fitzgerald, G F; Stanton, C; Ross, R P

    2001-01-01

    The viability of the human probiotic strains Lactobacillus paracasei NFBC 338 and Bifidobacterium sp. strain UCC 35612 in reconstituted skim milk was assessed by confocal scanning laser microscopy using the LIVE/DEAD BacLight viability stain. The technique was rapid (milk and fermented milk. These results indicate the value of the microscopic approach for rapid viability testing of such probiotic products. In contrast, the numbers obtained by direct microscopic counting for Cheddar cheese and spray-dried probiotic milk powder were lower than those obtained by plate counting. These results highlight the limitations of LIVE/DEAD BacLight staining and the need to optimize the technique for different strain-product combinations. The minimum detection limit for in situ viability staining in conjunction with confocal scanning laser microscopy enumeration was approximately 10(8) bacteria/ml (equivalent to approximately 10(7) CFU/ml), based on Bifidobacterium sp. strain UCC 35612 counts in maximum-recovery diluent.

  13. Bacterial meningitis

    NARCIS (Netherlands)

    Roos, Karen L.; van de Beek, Diederik

    2010-01-01

    Bacterial meningitis is a neurological emergency. Empiric antimicrobial and adjunctive therapy should be initiated as soon as a single set of blood cultures has been obtained. Clinical signs suggestive of bacterial meningitis include fever, headache, meningismus, vomiting, photophobia, and an

  14. Blue light (470 nm) effectively inhibits bacterial and fungal growth

    Science.gov (United States)

    The activity of blue light (470nm) alone on (1) bacterial viability, and (2) with a food grade photosensitizer on filamentous fungal viability, was studied. Suspensions of the bacteria Leuconostoc mesenteroides (LM), Bacillus atrophaeus (BA), and Pseudomonas aeruginosa (PA) were prepared and aliquo...

  15. Pyrochemical recovery of actinides

    International Nuclear Information System (INIS)

    Laidler, J.J.

    1993-01-01

    This report discusses an important advantage of the Integral Fast Reactor (IFR) which is its ability to recycle fuel in the process of power generation, extending fuel resources by a considerable amount and assuring the continued viability of nuclear power stations by reducing dependence on external fuel supplies. Pyroprocessing is the means whereby the recycle process is accomplished. It can also be applied to the recovery of fuel constituents from spent fuel generated in the process of operation of conventional light water reactor power plants, offering the means to recover the valuable fuel resources remaining in that material

  16. Negative Effect of Proton-pump Inhibitors (PPIs) on Helicobacter pylori Growth, Morphology, and Urease Test and Recovery after PPI Removal--An In vitro Study.

    Science.gov (United States)

    Saniee, Parastoo; Shahreza, Somayeh; Siavoshi, Farideh

    2016-04-01

    Proton-pump inhibitor (PPI) consumption does lead to false-negative results of Helicobacter pylori diagnostic tests such as biopsy culture and rapid urease test (RUT). Helicobacter pylori isolates from 112 dyspeptic patients with (56.5%) or without (43.5%) PPI consumption were recruited for examining the negative effects of omeprazole (OMP), lansoprazole (LPZ), and pantoprazole (PAN) on H. pylori viability, morphology, and urease, in vitro. The effect of a sublethal concentration of OMP on bacterial features and their recovery after removal of OMP was also assessed. Of 112 culture-positive gastric biopsies, 87.5% were RUT positive and 12.5% RUT negative. There was a significant correlation between negative RUT results and PPI consumption (p pylori isolates. OMP and LPZ inhibited urease of 90.3% of isolates between 0 and 40 minutes and 54.4% between 20 and 40 minutes, respectively. PAN did not inhibit H. pylori growth and urease. Three 3-day (9 days) consecutive subcultures of H. pylori on brucella blood agar (BBA) supplemented with OMP resulted in reduced bacterial viability (1+), compared with control (4+), change of spiral morphology to coccoid, and reduction in pink color intensity in urea agar. Bacterial growth (1+), morphology, and urease test did not improve after the first 3-day and second 3-day (6 days) subcultures on BBA. However, relative recovery occurred after the third 3-day (9 days) subculture and complete recovery was observed after the fourth 3-day (12 days) subculture, as confluent growth (4+), 100% spiral cells, and strong urease test. Proton-pump Inhibitors exert transient negative effects on H. pylori viability, morphology, and urease test. Accordingly, cessation of PPI consumption at least 12 days before endoscopy could help avoiding false-negative results of H. pylori diagnostic tests. © 2015 John Wiley & Sons Ltd.

  17. Fluorescence techniques to detect and to assess viability of plant pathogenic bacteria

    NARCIS (Netherlands)

    Chitarra, L.G.

    2001-01-01

    Plant pathogenic bacteria cause major economic losses in commercial crop production worldwide every year. The current methods used to detect and to assess the viability of bacterial pathogens and to test seed lots or plants for contamination are usually based on plate assays or on

  18. Effect of three concentration techniques on viability of Cryptosporidium parvum oocysts recovered from bovine feces.

    OpenAIRE

    Bukhari, Z; Smith, H V

    1995-01-01

    Bovine fecal samples (1 g) negative for Cryptosporidium sp. oocysts were seeded with 7 x 10(4) Cryptosporidium parvum oocysts and purified by either water-ether concentration, sucrose density flotation, or zinc sulfate flotation to evaluate oocyst recovery. The effect of these purification techniques on the viability of recovered oocysts was also evaluated. Significantly higher numbers of seeded oocysts were recovered by water-ether concentration (recovery rate, 46 to 75%) than by sucrose den...

  19. Microencapsulation in alginate and chitosan microgels to enhance viability of Bifidobacterium longum for oral delivery

    Directory of Open Access Journals (Sweden)

    Timothy W. Yeung

    2016-04-01

    Full Text Available Probiotic microorganisms are incorporated into a wide variety of foods, supplements, and pharmaceuticals to promote human health and wellness. However, maintaining bacterial cell viability during storage and gastrointestinal transit remains a challenge. Encapsulation of bifidobacteria within food-grade hydrogel particles potentially mitigates their sensitivity to environmental stresses. In this study, Bifidobacterium longum subspecies and strains were encapsulated in core-shell microgels consisting of an alginate core and a microgel shell. Encapsulated obligate anaerobes Bifidobacterium longum subsp. infantis and Bifidobacterium longum subsp. longum exhibited differences in viability in a strain-dependent manner, without a discernable relationship to subspecies lineage. This includes viability under aerobic storage conditions and modeled gastrointestinal tract conditions. Coating alginate microgels with chitosan did not improve viability compared to cells encapsulated in alginate microgels alone, suggesting that modifying the surface charge alone does not enhance delivery. Thus hydrogel beads have great potential for improving the stability and efficacy of bifidobacterial probiotics in various nutritional interventions.

  20. Infrared signatures to discriminate viability of autoclaved Bacillus spores

    Science.gov (United States)

    Schneider, Matthew D. W.; Valentine, Nancy B.; Johnson, Timothy J.

    2011-11-01

    Optical methods can offer good sensitivity for detecting small amounts of chemicals and biologicals, and as these methods mature, are some of the few techniques that can offer true standoff detection. For detection of biological species, determining the viability is clearly important: Certain species of gram-positive bacteria are capable of forming endospores, specialized structures that arise when living conditions become unfavorable or little growth medium is available. Spores are also resistant to many chemicals as well as changes in heat or pH; such spores can remain dormant from months to years until more favorable conditions arise, resulting in germination back to the vegetative state. This persistence characteristic of bacterial spores allows for contamination of a surface (e.g. food or medical equipment) even after the surface has been nominally cleaned. Bacterial spores have also been used as biological weapons, as in the case of B. anthracis. Thus, having rapid analytical methods to determine a spore's viability after attempts to clean a given environment is crucial. The increasing availability of portable spectrometers may provide a key to such rapid onsite analysis. The present study was designed to determine whether infrared spectroscopy may be used to differentiate between viable vs. dead B. subtilis and B. atrophaeus spores. Preliminary results show that the reproducible differences in the IR signatures can be used to identify the viable vs. the autoclaved (dead) spores.

  1. Bacterial Proteasomes.

    Science.gov (United States)

    Jastrab, Jordan B; Darwin, K Heran

    2015-01-01

    Interest in bacterial proteasomes was sparked by the discovery that proteasomal degradation is required for the pathogenesis of Mycobacterium tuberculosis, one of the world's deadliest pathogens. Although bacterial proteasomes are structurally similar to their eukaryotic and archaeal homologs, there are key differences in their mechanisms of assembly, activation, and substrate targeting for degradation. In this article, we compare and contrast bacterial proteasomes with their archaeal and eukaryotic counterparts, and we discuss recent advances in our understanding of how bacterial proteasomes function to influence microbial physiology.

  2. Genetic factors in Threatened Species Recovery Plans on three continents

    Science.gov (United States)

    Threatened species' recovery planning is applied globally to stem the current species extinction crisis. Evidence supports a key role of genetic processes, such as inbreeding depression, in determining species viability. We examined whether genetic factors are considered in threa...

  3. Effect of three concentration techniques on viability of Cryptosporidium parvum oocysts recovered from bovine feces.

    Science.gov (United States)

    Bukhari, Z; Smith, H V

    1995-01-01

    Bovine fecal samples (1 g) negative for Cryptosporidium sp. oocysts were seeded with 7 x 10(4) Cryptosporidium parvum oocysts and purified by either water-ether concentration, sucrose density flotation, or zinc sulfate flotation to evaluate oocyst recovery. The effect of these purification techniques on the viability of recovered oocysts was also evaluated. Significantly higher numbers of seeded oocysts were recovered by water-ether concentration (recovery rate, 46 to 75%) than by sucrose density (24 to 65%) or zinc sulfate (22 to 41%) flotation methods. In addition, water-ether concentration did not exert a significant effect on the viability of the population of oocysts recovered, whereas sucrose density flotation and zinc sulfate flotation selectively concentrated viable oocysts. The water-ether concentration procedure is recommended for use in epidemiological studies in which both oocyst enumeration and viability assessment are required. PMID:8567888

  4. Economic viability of anaerobic digestion

    Energy Technology Data Exchange (ETDEWEB)

    Wellinger, A. [INFOENERGIE, Ettenhausen (Switzerland)

    1996-01-01

    The industrial application of anaerobic digestion is a relatively new, yet proven waste treatment technology. Anaerobic digestion reduces and upgrades organic waste, and is a good way to control air pollution as it reduces methane and nitrous gas emissions. For environmental and energy considerations, anaerobic digestion is a nearly perfect waste treatment process. However, its economic viability is still in question. A number of parameters - type of waste (solid or liquid), digester system, facility size, product quality and end use, environmental requirements, cost of alternative treatments (including labor), and interest rates - define the investment and operating costs of an anaerobic digestion facility. Therefore, identical facilities that treat the same amount and type of waste may, depending on location, legislation, and end product characteristics, reveal radically different costs. A good approach for evaluating the economics of anaerobic digestion is to compare it to treatment techniques such as aeration or conventional sewage treatment (for industrial wastewater), or composting and incineration (for solid organic waste). For example, the cost (per ton of waste) of in-vessel composting with biofilters is somewhat higher than that of anaerobic digestion, but the investment costs 1 1/2 to 2 times more than either composting or anaerobic digestion. Two distinct advantages of anaerobic digestion are: (1) it requires less land than either composting or incinerating, which translates into lower costs and milder environmental and community impacts (especially in densely populated areas); and (2) it produces net energy, which can be used to operate the facility or sold to nearby industries.

  5. Leading a Recovery-oriented Social Enterprise.

    Science.gov (United States)

    Raeburn, Toby; Hungerford, Catherine; Sayers, Jan; Escott, Phil; Lopez, Violeta; Cleary, Michelle

    2015-05-01

    Recovery-oriented mental health services promote the principles of recovery, such as hope and optimism, and are characterized by a personalized approach to developing consumer self-determination. Nurse leaders are increasingly developing such services as social enterprises, but there is limited research on the leadership of these programs. Leading a recovery-oriented mental health nurse social enterprise requires visionary leadership, collaboration with consumers and local health providers, financial viability, and commitment to recovery-focused practice. This article describes the framework of an Australian mental health nursing social enterprise, including the service attributes and leadership lessons that have been learned from developing program sustainability.

  6. Bacterial adhesion

    NARCIS (Netherlands)

    Loosdrecht, van M.C.M.

    1988-01-01

    As mentioned in the introduction of this thesis bacterial adhesion has been studied from a variety of (mostly practice oriented) starting points. This has resulted in a range of widely divergent approaches. In order to elucidate general principles in bacterial adhesion phenomena, we felt it

  7. Pollen viability and membrane lipid composition

    NARCIS (Netherlands)

    Bilsen, van D.G.J.L.

    1993-01-01

    In this thesis membrane lipid composition is studied in relation to pollen viability during storage. Chapter 1 reviews pollen viability, membranes in the dry state and membrane changes associated with cellular aging. This chapter is followed by a study of age-related changes in phospholipid

  8. Terminology for pregnancy loss prior to viability

    DEFF Research Database (Denmark)

    Kolte, A M; Bernardi, L A; Christiansen, O B

    2015-01-01

    Pregnancy loss prior to viability is common and research in the field is extensive. Unfortunately, terminology in the literature is inconsistent. The lack of consensus regarding nomenclature and classification of pregnancy loss prior to viability makes it difficult to compare study results from d...

  9. Does the balanced scorecard support organizational viability?

    NARCIS (Netherlands)

    Achterbergh, J.M.I.M.; Beeres, R.J.M.; Vriens, D.J.

    2003-01-01

    In this paper we assess whether the balanced scorecard (BSC) supports the necessary functions for organizational viability. To this purpose, we use the viable system model (VSM) as a means to describe the functions required for organizational viability. Then we use the VSM as a template to assess

  10. Disaster Debris Recovery Database - Recovery

    Data.gov (United States)

    U.S. Environmental Protection Agency — The US EPA Disaster Debris Recovery Database (DDRD) promotes the proper recovery, recycling, and disposal of disaster debris for emergency responders at the federal,...

  11. Nitrate augmented myocardial viability assessment

    International Nuclear Information System (INIS)

    Wadhwa, S.; Mansberb, R.; Fernandes, V.B.

    1997-01-01

    Full text: 24 hour 201 TI reinjection imaging improves myocardial viability detection when compared to standard 3-4 hour redistribution imaging, however, it is a time-consuming approach and some images do not provide adequate quality due to high background activity on the delayed scan. We tested whether sensitivity of redistribution and same day reinjection imaging could be improved by giving short-acting nitrates immediately prior to redistribution and reinjection imaging. Eighteen patients underwent a stress test (exercise or pharmacological) and 4 hour redistribution 201 TI SPECT study. Immediately after redistribution imaging, each patient was given 600 μg of sublingual glyceryl trinitrate and reimaged 15-20 minutes later (nitrate augmented image). Immediately following nitrate augmentation imaging, each patient was reinjected with 30 MBq of 201 TI and reimaged 20 minutes later (nitrate augmented reinjection images). Each patient returned 24 hours later and was reinjected with 40 MBq of 201 TI and imaged 20 minutes later (24 hour reinjection images). In all, each patient had five SPECT images as follows: stress/redistribution/ nitrate augmented redistribution/nitrate augmented same day reinjection/ 24 hour reinjection. The myocardium was divided into 11 segments and perfusion to each segment was scored by consensus method (2 blinded assessors) on a 4 point graded scale (0 = no perfusion, 1 = minimal perfusion, 2 = moderate perfusion, 3 = normal perfusion). Perfusion scores were analysed on a segment by segment basis; as well, each patient was given an overall perfusion score equal to the sum of the perfusion score for each segment. 150 segments with reduced perfusion were identified, of these 23 (15.3%) showed improvement in the redistribution images, 60 (40%) segments improved in the nitrate augmented images, 49 (32.7%) improved in the nitrate augmented reinjection images and 52 (34.7%) improved in the 24 hour reinjection images. To assess overall cardiac

  12. The viability and intestinal epithelial cell adhesion of probiotic strain combination--in vitro study.

    Science.gov (United States)

    Piątek, Jacek; Gibas-Dorna, Magdalena; Olejnik, Anna; Krauss, Hanna; Wierzbicki, Krzysztof; Żukiewicz-Sobczak, Wioletta; Głowacki, Maciej

    2012-01-01

    To be effective, probiotic bacteria must exhibit a number of functional characteristics, including the resistance to gastric acidity and the ability to adhere to the intestinal epithelium. In this study, we examined in vitro the viability of lactic acid bacteria (LAB) combination after exposure to low pH, and the adhesion of LAB to Caco-2 cells during coincubation of 9 bacterial strains. To test bacterial viability, 6 commercially available products were incubated in 0.1 N HCl at pH 1.2 for 60 min. The greatest growth inhibition was noted for the non-capsulated product containing the Lactobacillus rhamnosus strain (log reduction of CFU = 6.4), and the best survival observed for the product containing 9 bacterial strains, equipped with a modern capsule made according to the Multi-Resistant Encapsulation technology (log reduction of CFU = 0.1). In the adhesion experiment, the combination of 9 bacterial strains was added to 17-day-old Caco-2 cell culture for 90 min. The greatest efficiency of adhesion was observed for the inoculum containing 5.5x10(8) CFU/mL/9.6 cm(2) of Caco-2 and the dose of probiotic bacteria of 190 cells per one Caco-2 cell. As a result, approximately 157 bacterial cells adhered to one Caco-2 cell. The results indicate that the combination of 9 bacterial strains in the examined product is characterized as highly adhesive.

  13. Bacterial Vaginosis

    Science.gov (United States)

    ... Archive STDs Home Page Bacterial Vaginosis (BV) Chlamydia Gonorrhea Genital Herpes Hepatitis HIV/AIDS & STDs Human Papillomavirus ( ... of getting other STDs, such as chlamydia and gonorrhea . These bacteria can sometimes cause pelvic inflammatory disease ( ...

  14. Intraspecific variation in pollen viability, germination and ...

    African Journals Online (AJOL)

    Oleaceae) cultivars 'Koroneiki', 'Mastoidis' and 'Kalamata' was studied with scanning electron microscopy to identify genotype- distinguishing characters that could be employed for morphological cultivar discrimination. Pollen viability and germination ...

  15. Generalized Recovery

    DEFF Research Database (Denmark)

    Skov Jensen, Christian; Lando, David; Heje Pedersen, Lasse

    of Ross (2015). Our characterization is simple and intuitive, linking recovery to the relation between the number of time periods on the number of states. When recovery is feasible, our model is easy to implement, allowing a closed-form linearized solution. We implement our model empirically, testing...... the predictive power of the recovered expected return, crash risk, and other recovered statistics....

  16. Backup & Recovery

    CERN Document Server

    Preston, W

    2009-01-01

    Packed with practical, freely available backup and recovery solutions for Unix, Linux, Windows, and Mac OS X systems -- as well as various databases -- this new guide is a complete overhaul of Unix Backup & Recovery by the same author, now revised and expanded with over 75% new material.

  17. BACTERIAL CONSORTIUM

    Directory of Open Access Journals (Sweden)

    Payel Sarkar

    2013-01-01

    Full Text Available Petroleum aromatic hydrocarbons like benzen e, toluene, ethyl benzene and xylene, together known as BTEX, has almost the same chemical structure. These aromatic hydrocarbons are released as pollutants in th e environment. This work was taken up to develop a solvent tolerant bacterial cons ortium that could degrade BTEX compounds as they all share a common chemical structure. We have isolated almost 60 different types of bacterial strains from different petroleum contaminated sites. Of these 60 bacterial strains almost 20 microorganisms were screene d on the basis of capability to tolerate high concentration of BTEX. Ten differe nt consortia were prepared and the compatibility of the bacterial strains within the consortia was checked by gram staining and BTEX tolerance level. Four successful mi crobial consortia were selected in which all the bacterial strains concomitantly grew in presence of high concentration of BTEX (10% of toluene, 10% of benzene 5% ethyl benzene and 1% xylene. Consortium #2 showed the highest growth rate in pr esence of BTEX. Degradation of BTEX by consortium #2 was monitored for 5 days by gradual decrease in the volume of the solvents. The maximum reduction observed wa s 85% in 5 days. Gas chromatography results also reveal that could completely degrade benzene and ethyl benzene within 48 hours. Almost 90% degradation of toluene and xylene in 48 hours was exhibited by consortium #2. It could also tolerate and degrade many industrial solvents such as chloroform, DMSO, acetonitrile having a wide range of log P values (0.03–3.1. Degradation of aromatic hydrocarbon like BTEX by a solvent tolerant bacterial consortium is greatly significant as it could degrade high concentration of pollutants compared to a bacterium and also reduces the time span of degradation.

  18. The effect of single-walled carbon nanotubes on Escherichia coli: multiple indicators of viability

    Energy Technology Data Exchange (ETDEWEB)

    Le, Tu Thi Anh; McEvoy, John, E-mail: john.mcevoy@ndsu.edu; Khan, Eakalak [North Dakota State University, Environmental and Conservation Sciences Program (United States)

    2015-01-15

    The impact of single-walled carbon nanotubes (SWCNTs) on Escherichia coli ATCC 8739 was investigated using four indicators of viability: enzyme activity, membrane integrity, plate count, and total RNA. The study examined the effects of SWCNT concentration (5, 10, 20, 50, 100, 200, 500, and 1,000 μg/ml), SWCNT length (0.5–2 and 5–30 μm), and bacterial density (6.5 log{sub 10} CFU and 9 log{sub 10} CFU per treatment) on E. coli ATCC 8739 viability. Results show that anti-bacterial activity is dependent on both the length and concentration of SWCNTs. Long SWCNTs (5–30 µm) were more toxic for E. coli than short SWCNTs (0.5–2 µm). The susceptibility of E. coli to SWCNTs was dependent on the initial density of cells in the treatment, with cells at the higher density being more resistant. Estimates of viability reductions were generally similar for the four assays examined; however, the beta galactosidase and LIVE/DEAD assays were more conservative than the plate count as indicators of viability reductions.

  19. Bacterial Ecology

    DEFF Research Database (Denmark)

    Fenchel, Tom

    2011-01-01

    Bacterial ecology is concerned with the interactions between bacteria and their biological and nonbiological environments and with the role of bacteria in biogeochemical element cycling. Many fundamental properties of bacteria are consequences of their small size. Thus, they can efficiently exploit...

  20. Bacterial meningitis

    NARCIS (Netherlands)

    Heckenberg, Sebastiaan G. B.; Brouwer, Matthijs C.; van de Beek, Diederik

    2014-01-01

    Bacterial meningitis is a neurologic emergency. Vaccination against common pathogens has decreased the burden of disease. Early diagnosis and rapid initiation of empiric antimicrobial and adjunctive therapy are vital. Therapy should be initiated as soon as blood cultures have been obtained,

  1. Bacterial lipases

    NARCIS (Netherlands)

    Jaeger, Karl-Erich; Ransac, Stéphane; Dijkstra, Bauke W.; Colson, Charles; Heuvel, Margreet van; Misset, Onno

    Many different bacterial species produce lipases which hydrolyze esters of glycerol with preferably long-chain fatty acids. They act at the interface generated by a hydrophobic lipid substrate in a hydrophilic aqueous medium. A characteristic property of lipases is called interfacial activation,

  2. Bacterial Ecology

    DEFF Research Database (Denmark)

    Fenchel, Tom

    2011-01-01

    , the production and oxidation of methane, nitrate reduction and fixation of atmospheric nitrogen are exclusively carried out by different groups of bacteria. Some bacterial species – ‘extremophiles’ – thrive in extreme environments in which no eukaryotic organisms can survive with respect to temperature, salinity...

  3. Bacterial Vaginosis

    Science.gov (United States)

    ... that coats the walls of the vagina Vaginal discharge with an unpleasant or fishlike odor Vaginal pain or itching Burning during urination Doctors are unsure of the incubation period for bacterial vaginosis. How Is the Diagnosis Made? Your child’s pediatrician can make the diagnosis ...

  4. Bacterial stress

    Indian Academy of Sciences (India)

    First page Back Continue Last page Graphics. Bacterial stress. Physicochemical and chemical parameters: temperature, pressure, pH, salt concentration, oxygen, irradiation. Nutritional depravation: nutrient starvation, water shortage. Toxic compounds: Antibiotics, heavy metals, toxins, mutagens. Interactions with other cells: ...

  5. Bacterial Adhesion & Blocking Bacterial Adhesion

    DEFF Research Database (Denmark)

    Vejborg, Rebecca Munk

    2008-01-01

    reduce or delay bacterial biofilm formation of a range of urinary tract infectious E.coli and Klebsiella isolates. Several other proteinaceous coatings were also found to display anti-adhesive properties, possibly providing a measure for controlling the colonization of implant materials. Several other...... components. These substances may both mediate and stabilize the bacterial biofilm. Finally, several adhesive structures were examined, and a novel physiological biofilm phenotype in E.coli biofilms was characterized, namely cell chain formation. The autotransporter protein, antigen 43, was implicated...

  6. Viability analysis in biological evaluations: Concepts of population viability analysis, biological population, and ecological scale

    Science.gov (United States)

    Gregory D. Hayward; John R. Squires

    1994-01-01

    Environmental protection strategies often rely on environmental impact assessments. As part of the assessment process biologists are routinely asked to evaluate the effects of management actions on plants and animals. This evaluation often requires that biologists make judgments about the viability of affected populations. However, population viability...

  7. Immobilization of plant protoplasts: Viability studies.

    Science.gov (United States)

    Linsefors, L; Brodelius, P

    1985-02-01

    Protoplasts of Daucus carota Ca68 and Catharanthus roseus have been immobilized by entrapment in gelforming polysaccharides (kappa-carrageenan, agarose and alginate). Uniform spherical beads of carrageenan and agarose containing the protoplasts have been prepared by utilizing an inert hydrophobic phase (vegetable oil). The entrapped protoplasts are viable and stabilized towards osmotic shock by the polymeric backbone. Standard methods have been used to study the viability and integrity of the entrapped protoplasts. Upon incubation in a relatively simple medium the immobilized protoplasts show a much higher viability after 14 days as compared to free protoplasts under the same conditions. The viability of D. carota protoplasts has also been monitored by an enzyme activity present in the cells (digitoxigenin 58-hydroxylase).

  8. Probiotic viability – does it matter?

    Directory of Open Access Journals (Sweden)

    Sampo J. Lahtinen

    2012-06-01

    Full Text Available Probiotics are viable by definition, and viability of probiotics is often considered to be a prerequisite for the health benefits. Indeed, the overwhelming majority of clinical studies in the field have been performed with viable probiotics. However, it has also been speculated that some of the mechanisms behind the probiotic health effects may not be dependent on the viability of the cells and, therefore, is also possible that also non-viable probiotics could have some health benefits. The efficacy of non-viable probiotics has been assessed in a limited number of studies, with varying success. While it is clear that viable probiotics are more effective than non-viable probiotics and that, in many cases, viability is indeed a prerequisite for the health benefit, there are also some cases where it appears that non-viable probiotics could also have beneficial effects on human health.

  9. Bacterial lipases

    OpenAIRE

    Jaeger, Karl-Erich; Ransac, Stéphane; Dijkstra, Bauke W.; Colson, Charles; Heuvel, Margreet van; Misset, Onno

    1994-01-01

    Many different bacterial species produce lipases which hydrolyze esters of glycerol with preferably long-chain fatty acids. They act at the interface generated by a hydrophobic lipid substrate in a hydrophilic aqueous medium. A characteristic property of lipases is called interfacial activation, meaning a sharp increase in lipase activity observed when the substrate starts to form an emulsion, thereby presenting to the enzyme an interfacial area. As a consequence, the kinetics of a lipase rea...

  10. Detection of viability by percent thallium uptake with conventional thallium scintigraphy

    International Nuclear Information System (INIS)

    Imai, Kamon; Araki, Yasushi; Horiuchi, Kou-ichi; Yumikura, Sei; Saito, Satoshi; Ozawa, Yukio; Kan-matsuse, Katsuo; Hagiwara, Kazuo.

    1994-01-01

    Thallium myocardial scintigraphy (TMS) is used for diagnosis of viability in infarcted myocardium before coronary revascularization. Underestimation of viability by TMS has been reported by many investigators. To evaluate viability precisely, thallium re-injection method or 24 hour delayed imaging is performed. However, these techniques are not convenient and are difficult to perform in clinical practice. Percent T1-uptake method was developed for predicting myocardial viability. To evaluate usefulness of this method, TMS was performed before and after PTCA in 23 patients with myocardial infarction. Left ventricle was divided into 3 layers, then each layer was divided into 4 segments (12 segments in total). Forth three segments showed recovery of perfusion on TMS after PTCA. Viability in infarcted myocardium is predicted by 1) redistribution (RD), 2) %T1-uptake≥45% on the image immediately after exercise (TE), and 3) %T1-uptake≥45% on delayed image (TD). Sensitivity was RD: 60%, TE: 90% and TD: 95% (p<0.001 vs. RD). Specificity was RD: 74%, TE: 68%, and TD: 60% (NS). Predictive accuracy (PA) was RD: 69%, TE: 77%, TD: 73% (NS). Compared with RD, %T1-uptake, either TE or TD, increased sensitivity with slightly improved PA, but decreased specificity slightly. Therefore %T1-uptake would be a sensitive and useful predictor to find patients who are most likely to benefit from re-vascularization. (author)

  11. CONSERVATION OF THE VIABILITY AND VIGOR OF Araucaria angustifolia (Bert. O. Kuntze SEEDS DURING THE STORAGE

    Directory of Open Access Journals (Sweden)

    Cristhyane Garcia

    2014-12-01

    Full Text Available The conservation of Araucaria seeds is widely compromised in function of their recalcitrant feature, which hampers the planning of recovery actions of the degraded populations. Therefore, the objective of this study was to monitor the physiological changes in Araucaria seeds under controlled storage conditions, in order to get insights as to the viability and vigor conservation. The physiological quality of freshly harvested seeds was evaluated and every 60 days throughout the 180 days-storage period in laboratory ambient without thermal control, refrigerator (5 ° C, and freezer (-18 ° C until the final period of 180 days. After each sampling period, the seed viability (germination and tetrazolium tests and vigor (artificial aging, germination speed index – IVG and electrical conductivity were assessed. A reduction in the normal seedlings percentage was noticed over the period of storage of Araucaria seeds. The conservation in freezer and the lack of thermal control caused a complete loss of the seed viability at 60 and 180 days of storage, respectively. However, the refrigerator storage promoted the conservation of seed viability, with 64% germination after 180 days of storage, an event associated with the reduction of the metabolic activity of seeds. Based on the viability and vigor tests, it was concluded that storage in refrigerator provided longer storage periods to Araucaria seeds in comparison to the other storage conditions herein studied.

  12. The Viability of "Roe v. Wade."

    Science.gov (United States)

    Belson, Nicole

    1989-01-01

    Examines four issues involved in "Webster v. Reproductive Health Services:" (1) the preamble to the 1986 Missouri statute on abortion, (2) prohibiting public employees from performing abortions, (3) public funds for encouraging abortion, and (4) gestational age and viability provision. Focuses on the effects on the continuing vitality of…

  13. Economic Viability and Marketing Strategies of Periwinkle ...

    African Journals Online (AJOL)

    The economic viability and marketing strategies of periwinkle species in twelve major markets across Rivers State Nigeria were investigated using structured questionnaires. The results indicated that marketing strategies are enroute, through harvesters (collectors), to wholesalers (those who purchase in small quantities ...

  14. Pollen morphology and viability in Bromeliaceae

    Directory of Open Access Journals (Sweden)

    EVERTON H. SOUZA

    2017-12-01

    Full Text Available ABSTRACT Pollen morphology characterization is important in taxonomy, conservation and plant breeding, and pollen viability studies can support breeding programs. This study investigated pollen morphology and male fertility in 18 species of Bromeliaceae with ornamental potential. For morphological characterization, pollen grains were acetolyzed and characterization of exine was done using scanning and transmission electron microscopy. Pollen viability was investigated by in vitro germination and histochemical tests. Species belonging to Aechmea and Ananas genera presented medium size pollen, except for Ae. fasciata, with large pollen. Al. nahoumii, P. sagenarius and the Vriesea species analyzed showed large pollen, except for V. carinata, with very large pollen. Pollen of Aechmea, Ananas and P. sagenarius presented bilateral symmetry, diporate, exine varying from tectate to semitectate. Al. nahoumii and Vriesea species presented pollen with bilateral symmetry, monocolpate; exine was semitectate, reticulate and heterobrochate. Germination percentage and tube growth were greater in SM and BKM media. Histochemical tests showed pollen viability above 70% for all species, except for Ananas sp. (40%. Pollen morphology is important for the identification of species, especially in this family, which contains a large number of species. High rates of viability favor fertilization and seed production, essential for efficient hybrid production and conservation.

  15. Pollen morphology and viability in Bromeliaceae.

    Science.gov (United States)

    Souza, Everton H; Souza, Fernanda V D; Rossi, Mônica L; Packer, Renan M; Cruz-Barros, Maria Amelia V; Martinelli, Adriana P

    2017-01-01

    Pollen morphology characterization is important in taxonomy, conservation and plant breeding, and pollen viability studies can support breeding programs. This study investigated pollen morphology and male fertility in 18 species of Bromeliaceae with ornamental potential. For morphological characterization, pollen grains were acetolyzed and characterization of exine was done using scanning and transmission electron microscopy. Pollen viability was investigated by in vitro germination and histochemical tests. Species belonging to Aechmea and Ananas genera presented medium size pollen, except for Ae. fasciata, with large pollen. Al. nahoumii, P. sagenarius and the Vriesea species analyzed showed large pollen, except for V. carinata, with very large pollen. Pollen of Aechmea, Ananas and P. sagenarius presented bilateral symmetry, diporate, exine varying from tectate to semitectate. Al. nahoumii and Vriesea species presented pollen with bilateral symmetry, monocolpate; exine was semitectate, reticulate and heterobrochate. Germination percentage and tube growth were greater in SM and BKM media. Histochemical tests showed pollen viability above 70% for all species, except for Ananas sp. (40%). Pollen morphology is important for the identification of species, especially in this family, which contains a large number of species. High rates of viability favor fertilization and seed production, essential for efficient hybrid production and conservation.

  16. Viability of mesenchymal stem cells during electrospinning

    Directory of Open Access Journals (Sweden)

    G. Zanatta

    2012-02-01

    Full Text Available Tissue engineering is a technique by which a live tissue can be re-constructed and one of its main goals is to associate cells with biomaterials. Electrospinning is a technique that facilitates the production of nanofibers and is commonly used to develop fibrous scaffolds to be used in tissue engineering. In the present study, a different approach for cell incorporation into fibrous scaffolds was tested. Mesenchymal stem cells were extracted from the wall of the umbilical cord and mononuclear cells from umbilical cord blood. Cells were re-suspended in a 10% polyvinyl alcohol solution and subjected to electrospinning for 30 min under a voltage of 21 kV. Cell viability was assessed before and after the procedure by exclusion of dead cells using trypan blue staining. Fiber diameter was observed by scanning electron microscopy and the presence of cells within the scaffolds was analyzed by confocal laser scanning microscopy. After electrospinning, the viability of mesenchymal stem cells was reduced from 88 to 19.6% and the viability of mononuclear cells from 99 to 8.38%. The loss of viability was possibly due to the high viscosity of the polymer solution, which reduced the access to nutrients associated with electric and mechanical stress during electrospinning. These results suggest that the incorporation of cells during fiber formation by electrospinning is a viable process that needs more investigation in order to find ways to protect cells from damage.

  17. Recovery Spirituality

    Directory of Open Access Journals (Sweden)

    Ernest Kurtz

    2015-01-01

    Full Text Available There is growing interest in Alcoholics Anonymous (A.A. and other secular, spiritual, and religious frameworks of long-term addiction recovery. The present paper explores the varieties of spiritual experience within A.A., with particular reference to the growth of a wing of recovery spirituality promoted within A.A. It is suggested that the essence of secular spirituality is reflected in the experience of beyond (horizontal and vertical transcendence and between (connection and mutuality and in six facets of spirituality (Release, Gratitude, Humility, Tolerance, Forgiveness, and a Sense of Being-at-home shared across religious, spiritual, and secular pathways of addiction recovery. The growing varieties of A.A. spirituality (spanning the “Christianizers” and “Seculizers” reflect A.A.’s adaptation to the larger diversification of religious experience and the growing secularization of spirituality across the cultural contexts within which A.A. is nested.

  18. Molecular Basis of Bacterial Longevity

    Directory of Open Access Journals (Sweden)

    Kieran B. Pechter

    2017-11-01

    Full Text Available It is well known that many bacteria can survive in a growth-arrested state for long periods of time, on the order of months or even years, without forming dormant structures like spores or cysts. How is such longevity possible? What is the molecular basis of such longevity? Here we used the Gram-negative phototrophic alphaproteobacterium Rhodopseudomonas palustris to identify molecular determinants of bacterial longevity. R. palustris maintained viability for over a month after growth arrest due to nutrient depletion when it was provided with light as a source of energy. In transposon sequencing (Tn-seq experiments, we identified 117 genes that were required for long-term viability of nongrowing R. palustris cells. Genes in this longevity gene set are annotated to play roles in a number of cellular processes, including DNA repair, tRNA modification, and the fidelity of protein synthesis. These genes are critically important only when cells are not growing. Three genes annotated to affect translation or posttranslational modifications were validated as bona fide longevity genes by mutagenesis and complementation experiments. These genes and others in the longevity gene set are broadly conserved in bacteria. This raises the possibility that it will be possible to define a core set of longevity genes common to many bacterial species.

  19. Biochemical Characteristics and Viability of Probiotic and Yogurt Bacteria in Yogurt during the Fermentation and Refrigerated Storage

    Directory of Open Access Journals (Sweden)

    F Sarvari

    2014-09-01

    Full Text Available This research aimed to investigate the viability of probiotic bacteria (Lactobacillus acidophilus LA-5 and Bifidobacterium lactis BB-12 and yogurt bacteria (Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus in yogurt during the fermentation, immediately after fermentation and during refrigerated storage (21 d, 4˚C. Also the biochemical characteristics of milk as affected by the commercial 4-strain mixed starter culture were investigated. Storage time affected the viability of all bacterial species. The concentration of lactic acid during the fermentation increased in parallel with the titrable acidity, and the concentration of acetic acid was proportional to the viability of Bifidobacterium lactis. The acetaldehyde level was decreased in the yogurt from day 0 up to the end of the storage. Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus were multiplied considerably during the fermentation. Streptococcus thermophilus could maintain its viability to the highest level, but Lactobacillus delbrueckii ssp. bulgaricus lost its viability rapidly during the cold storage compared to Streptococcus thermophilus. The multiplication and viability of probiotic bacteria were also influenced by the associative strains and species of yogurt organisms. Bifidobacteria counts were satisfactory. The loss of viability for bifidobacteria was gradual and steady during the storage, and they showed good stability during the storage as compared to Lactobacillus acidophilus.

  20. Generalized Recovery

    DEFF Research Database (Denmark)

    Skov Jensen, Christian; Lando, David; Heje Pedersen, Lasse

    We characterize when physical probabilities, marginal utilities, and the discount rate can be recovered from observed state prices for several future time periods. Our characterization makes no assumptions of the probability distribution, thus generalizing the time-homogeneous stationary model...... of Ross (2015). Our characterization is simple and intuitive, linking recovery to the relation between the number of time periods and the number of states. When recovery is feasible, our model is easy to implement, allowing a closed-form linearized solution. We implement our model empirically, testing...

  1. Generalized Recovery

    DEFF Research Database (Denmark)

    Jensen, Christian Skov; Lando, David; Pedersen, Lasse Heje

    We characterize when physical probabilities, marginal utilities, and the discount rate can be recovered from observed state prices for several future time periods. Our characterization makes no assumptions of the probability distribution, thus generalizing the time-homogeneous stationary model...... of Ross (2015). Our characterization is simple and intuitive, linking recovery to the relation between the number of time periods on the number of states. When recovery is feasible, our model is easy to implement, allowing a closed-form linearized solution. We implement our model empirically, testing...

  2. Generalized Recovery

    DEFF Research Database (Denmark)

    Jensen, Christian Skov; Lando, David; Pedersen, Lasse Heje

    We characterize when physical probabilities, marginal utilities, and the discount rate can be recovered from observed state prices for several future time periods. We make no assumptions of the probability distribution, thus generalizing the time-homogeneous stationary model of Ross (2015......). Recovery is feasible when the number of maturities with observable prices is higher than the number of states of the economy (or the number of parameters characterizing the pricing kernel). When recovery is feasible, our model is easy to implement, allowing a closed-form linearized solution. We implement...... our model empirically, testing the predictive power of the recovered expected return and other recovered statistics....

  3. Assessment of probiotic viability during Cheddar cheese manufacture and ripening using propidium monoazide-PCR quantification

    Directory of Open Access Journals (Sweden)

    Emilie eDesfossés-Foucault

    2012-10-01

    Full Text Available The use of a suitable food carrier such as cheese could significantly enhance probiotic viability during storage. The main goal of this study was to assess viability of commercial probiotic strains during Cheddar cheesemaking and ripening (four to six months by comparing the efficiency of microbiological and molecular approaches. Molecular methods such as quantitative PCR (qPCR allow bacterial quantification, and DNA-blocking molecules such as propidium monoazide (PMA select only the living cells’ DNA. Cheese samples were manufactured with a lactococci starter and with one of three probiotic strains (Bifidobacterium animalis subsp. lactis BB-12, Lactobacillus rhamnosus RO011 or Lactobacillus helveticus RO052 or a mixed culture containing B. animalis subsp. lactis BB-12 and L. helveticus RO052 (MC1, both lactobacilli strains (MC2 or all three strains (MC3. DNA extractions were then carried out on PMA-treated and non-treated cell pellets in order to assess PMA treatment efficiency, followed by quantification using the 16S rRNA gene, the elongation factor Tu gene (tuf or the transaldolase gene (tal. Results with intact/dead ratios of bacteria showed that PMA-treated cheese samples had a significantly lower bacterial count than non-treated DNA samples (P<0.005, confirming that PMA did eliminate dead bacteria from PCR quantification. For both quantification methods, the addition of probiotic strains seemed to accelerate the loss of lactococci viability in comparison to control cheese samples, especially when L. helveticus RO052 was added. Viability of all three probiotic strains was also significantly reduced in mixed culture cheese samples (P<0.0001, B. animalis subsp. lactis BB-12 being the most sensitive to the presence of other strains. However, all probiotic strains did retain their viability (log nine cfu/g of cheese throughout ripening. This study was successful in monitoring living probiotic species in Cheddar cheese samples through PMA-qPCR.

  4. Recognition of microbial viability via TLR8 drives TFH cell differentiation and vaccine responses

    DEFF Research Database (Denmark)

    Ugolini, Matteo; Gerhard, Jenny; Burkert, Sanne

    2018-01-01

    Live attenuated vaccines are generally highly efficacious and often superior to inactivated vaccines, yet the underlying mechanisms of this remain largely unclear. Here we identify recognition of microbial viability as a potent stimulus for follicular helper T cell (TFH cell) differentiation...... and vaccine responses. Antigen-presenting cells (APCs) distinguished viable bacteria from dead bacteria through Toll-like receptor 8 (TLR8)-dependent detection of bacterial RNA. In contrast to dead bacteria and other TLR ligands, live bacteria, bacterial RNA and synthetic TLR8 agonists induced a specific...... cytokine profile in human and porcine APCs, thereby promoting TFH cell differentiation. In domestic pigs, immunization with a live bacterial vaccine induced robust TFH cell and antibody responses, but immunization with its heat-killed counterpart did not. Finally, a hypermorphic TLR8 polymorphism...

  5. Effect of Lactobacillus reuteri on Cell Viability and PGE2 Production in Human Gingival Fibroblasts

    DEFF Research Database (Denmark)

    Castiblanco, Gina A.; Yucel-Lindberg, Tulay; Roos, Stefan

    2017-01-01

    (HGF) and its production of prostaglandin E2 (PGE2), when exposed to supernatants of two mixed Lactobacillus reuteri strains (ATCC PTA 5289 and DSM 17938). The experiments were conducted in the presence and absence of the pro-inflammatory cytokine IL-1β. L. reuteri strains were grown and the bacterial...... immune assay kits. Our findings showed that none of the L. reuteri supernatants were cytotoxic or affected the viability of HGF. The most concentrated bacterial supernatant stimulated the production of PGE2 by the gingival cells in a significant way in the presence of IL-1β (p ... that bacterial products secreted from L. reuteri might play a role in the resolution of inflammation in HGF. Thus, our findings justify further investigations on the influence of probiotic bacteria on gingival inflammatory reactions....

  6. Bacterial mitosis

    DEFF Research Database (Denmark)

    Møller-Jensen, Jakob; Borch, Jonas; Dam, Mette

    2003-01-01

    Bacterial DNA segregation takes place in an active and ordered fashion. In the case of Escherichia coli plasmid R1, the partitioning system (par) separates paired plasmid copies and moves them to opposite cell poles. Here we address the mechanism by which the three components of the R1 par system...... movement is powered by insertional polymerization of ParM. Consistently, we find that segregating plasmids are positioned at the ends of extending ParM filaments. Thus, the process of R1 plasmid segregation in E. coli appears to be mechanistically analogous to the actin-based motility operating...

  7. No. 347-Obstetric Management at Borderline Viability.

    Science.gov (United States)

    Ladhani, Noor Niyar N; Chari, Radha S; Dunn, Michael S; Jones, Griffith; Shah, Prakesh; Barrett, Jon F R

    2017-09-01

    The primary objective of this guideline was to develop consensus statements to guide clinical practice and recommendations for obstetric management of a pregnancy at borderline viability, currently defined as prior to 25+6 weeks. Clinicians involved in the obstetric management of women whose fetus is at the borderline of viability. Women presenting for possible birth at borderline viability. This document presents a summary of the literature and a general consensus on the management of pregnancies at borderline viability, including maternal transfer and consultation, administration of antenatal corticosteroids and magnesium sulfate, fetal heart rate monitoring, and considerations in mode of delivery. Medline, EMBASE, and Cochrane databases were searched using the following keywords: extreme prematurity, borderline viability, preterm, pregnancy, antenatal corticosteroids, mode of delivery. The results were then studied, and relevant articles were reviewed. The references of the reviewed studies were also searched, as were documents citing pertinent studies. The evidence was then presented at a consensus meeting, and statements were developed. The content and recommendations were developed by the consensus group from the fields of Maternal-Fetal Medicine, Neonatology, Perinatal Nursing, Patient Advocacy, and Ethics. The quality of evidence was rated using criteria described in the Grading of Recommendations Assessment, Development and Evaluation methodology framework (reference 1). The Board of the Society of Obstetricians and Gynaecologists of Canada approved the final draft for publication. The quality of evidence was rated using the criteria described in the Grading of Recommendations, Assessment, Development, and Evaluation methodology framework. The interpretation of strong and weak recommendations is described later. The Summary of Findings is available upon request. A multidisciplinary approach should be used in counselling women and families at borderline

  8. Novel chemically modified bacterial cellulose nanocomposite as potential biomaterial for stem cell therapy applications.

    Science.gov (United States)

    Xavier Acasigua, Gerson Arisoly; de Olyveira, Gabriel Molina; Manzine Costa, Ligia Maria; Braghirolli, Daikelly Iglesias; Medeiros Fossati, Anna Christina; Guastaldi, Antonio Carlos; Pranke, Patricia; Daltro, Gildásio de Cerqueira; Basmaji, Pierre

    2014-03-01

    Bacterial cellulose (BC) has become established as a remarkably versatile biomaterial and can be used in a wide variety of applied scientific applications, especially for medical devices. In this work, the bacterial cellulose fermentation process is modified by the addition of hyaluronic acid and gelatin (1% w/w) to the culture medium before the bacteria is inoculated. Hyaluronic acid and gelatin influence in bacterial cellulose was analyzed using Transmission Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). Adhesion and viability studies with human dental pulp stem cells using natural bacterial cellulose/hyaluronic acid as scaffolds for regenerative medicine are presented for the first time in this work. MTT viability assays show higher cell adhesion in bacterial cellulose/gelatin and bacterial cellulose/ hyaluronic acid scaffolds over time with differences due to fiber agglomeration in bacterial cellulose/gelatin. Confocal microscopy images showed that the cell were adhered and well distributed within the fibers in both types of scaffolds.

  9. Advances and Challenges in Viability Detection of Foodborne Pathogens

    Directory of Open Access Journals (Sweden)

    Dexin Zeng

    2016-11-01

    Full Text Available Foodborne outbreaks are a serious public health and food safety concern worldwide. There is a great demand for rapid, sensitive, specific, and accurate methods to detect microbial pathogens in foods. Conventional methods based on cultivation of pathogens have been the gold standard protocols; however, they take up to a week to complete. Molecular assays such as polymerase chain reaction (PCR, sequencing, microarray technologies have been widely used in detection of foodborne pathogens. Among molecular assays, PCR technology conventional and real-time PCR (qPCR is most commonly used in the foodborne pathogen detection because of its high sensitivity and specificity. However, a major drawback of PCR is its inability to differentiate the DNA from dead and viable cells, and this is a critical factor for the food industry, regulatory agencies and the consumer. To remedy this shortcoming, researchers have used biological dyes such as ethidium monoazide (EMA and propidium monoazide (PMA to pretreat samples before DNA extraction to intercalate the DNA of dead cells in food samples, and then proceed with regular DNA preparation and qPCR. By combining PMA treatment with qPCR (PMA-qPCR, scientists have applied this technology to detect viable cells of various bacterial pathogens in foods. The incorporation of PMA into PCR-based assays for viability detection of pathogens in foods has increased significantly in the last decade. On the other hand, some downsides with this approach have been noted, particularly to achieve complete suppression of signal of DNA from the dead cells present in some particular food matrix. Nowadays, there is a tendency of more and more researchers adapting this approach for viability detection; and a few commercial kits based on PMA are available in the market. As time goes on, more scientists apply this approach to a broader range of pathogen detections, this viability approach (PMA or other chemicals such as platinum compound

  10. Advances and Challenges in Viability Detection of Foodborne Pathogens.

    Science.gov (United States)

    Zeng, Dexin; Chen, Zi; Jiang, Yuan; Xue, Feng; Li, Baoguang

    2016-01-01

    Foodborne outbreaks are a serious public health and food safety concern worldwide. There is a great demand for rapid, sensitive, specific, and accurate methods to detect microbial pathogens in foods. Conventional methods based on cultivation of pathogens have been the gold standard protocols; however, they take up to a week to complete. Molecular assays such as polymerase chain reaction (PCR), sequencing, microarray technologies have been widely used in detection of foodborne pathogens. Among molecular assays, PCR technology [conventional and real-time PCR (qPCR)] is most commonly used in the foodborne pathogen detection because of its high sensitivity and specificity. However, a major drawback of PCR is its inability to differentiate the DNA from dead and viable cells, and this is a critical factor for the food industry, regulatory agencies and the consumer. To remedy this shortcoming, researchers have used biological dyes such as ethidium monoazide and propidium monoazide (PMA) to pretreat samples before DNA extraction to intercalate the DNA of dead cells in food samples, and then proceed with regular DNA preparation and qPCR. By combining PMA treatment with qPCR (PMA-qPCR), scientists have applied this technology to detect viable cells of various bacterial pathogens in foods. The incorporation of PMA into PCR-based assays for viability detection of pathogens in foods has increased significantly in the last decade. On the other hand, some downsides with this approach have been noted, particularly to achieve complete suppression of signal of DNA from the dead cells present in some particular food matrix. Nowadays, there is a tendency of more and more researchers adapting this approach for viability detection; and a few commercial kits based on PMA are available in the market. As time goes on, more scientists apply this approach to a broader range of pathogen detections, this viability approach (PMA or other chemicals such as platinum compound) may eventually

  11. Effect of cryopreservation and lyophilization on viability and growth of strict anaerobic human gut microbes.

    Science.gov (United States)

    Bircher, Lea; Geirnaert, Annelies; Hammes, Frederik; Lacroix, Christophe; Schwab, Clarissa

    2018-04-17

    Strict anaerobic gut microbes have been suggested as 'next-generation probiotics' for treating several intestinal disorders. The development of preservation techniques is of major importance for therapeutic application. This study investigated cryopreservation (-80°C) and lyophilization survival and storage stability (4°C for 3 months) of the strict anaerobic gut microbes Bacteroides thetaiotaomicron, Faecalibacterium prausnitzii, Roseburia intestinalis, Anaerostipes caccae, Eubacterium hallii and Blautia obeum. To improve preservation survival, protectants sucrose and inulin (both 5% w/v) were added for lyophilization and were also combined with glycerol (15% v/v) for cryopreservation. Bacterial fitness, evaluated by maximum growth rate and lag phase, viability and membrane integrity were determined using a standardized growth assay and by flow cytometry as markers for preservation resistance. Lyophilization was more detrimental to viability and fitness than cryopreservation, but led to better storage stability. Adding sucrose and inulin enhanced viability and the proportion of intact cells during lyophilization of all strains. Viability of protectant-free B. thetaiotaomicron, A. caccae and F. prausnitzii was above 50% after cryopreservation and storage and increased to above 80% if protectants were present. The addition of glycerol, sucrose and inulin strongly enhanced the viability of B. obeum, E. hallii and R. intestinalis from 0.03-2% in protectant-free cultures to 11-37%. This is the first study that quantitatively compared the effect of cryopreservation and lyophilization and the addition of selected protectants on viability and fitness of six strict anaerobic gut microbes. Our results suggest that efficiency of protectants is process- and species-specific. © 2018 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  12. Myocardial viability assessment using nuclear imaging

    International Nuclear Information System (INIS)

    Matsunari, Ichiro; Hisada, Kinichi; Taki, Junichi; Nakajima, Kenichi; Tonami, Norihisa

    2003-01-01

    Myocardial assessment continues to be an issue in patients with coronary artery disease and left ventricular dysfunction. Nuclear imaging has long played an important role in this field. In particular, PET imaging using 18 F-fluorodeoxyglucose is regarded as the metabolic gold standard of tissue viability, which has been supported by a wide clinical experience. Viability assessment using SPECT techniques has gained more wide-spread clinical acceptance than PET, because it is more widely available at lower cost. Moreover, technical advances in SPECT technology such as gated-SPECT further improve the diagnostic accuracy of the test. However, other imaging techniques such as dobutamine echocardiography have recently emerged as competitors to nuclear imaging. It is also important to note that they sometimes may work in a complementary fashion to nuclear imaging, indicating that an appropriate use of these techniques may significantly improve their overall accuracy. In keeping these circumstances in mind, further efforts are necessary to further improve the diagnostic performance of nuclear imaging as a reliable viability test. (author) 107 refs

  13. Effect of Lactobacillus reuteri on Cell Viability and PGE2 Production in Human Gingival Fibroblasts.

    Science.gov (United States)

    A Castiblanco, Gina; Yucel-Lindberg, Tulay; Roos, Stefan; Twetman, Svante

    2017-09-01

    Emerging evidence suggests that probiotic therapy can play a role in the prevention and management of oral inflammatory diseases through immunomodulation and down-regulation of the inflammatory cascade. The aim of this in vitro study was to investigate the viability of human gingival fibroblasts (HGF) and its production of prostaglandin E 2 (PGE 2 ), when exposed to supernatants of two mixed Lactobacillus reuteri strains (ATCC PTA 5289 and DSM 17938). The experiments were conducted in the presence and absence of the pro-inflammatory cytokine IL-1β. L. reuteri strains were grown and the bacterial supernatant was collected. The cell-free supernatant was diluted to concentrations equivalent to the ones produced by 0.5 to 5.0 × 10 7  CFU/mL bacteria. Cell viability was assessed with the MTT colorimetric assay and the amount of PGE 2 in the cell culture medium was determined using the monoclonal enzyme immune assay kits. Our findings showed that none of the L. reuteri supernatants were cytotoxic or affected the viability of HGF. The most concentrated bacterial supernatant stimulated the production of PGE 2 by the gingival cells in a significant way in the presence of IL-1β (p reuteri might play a role in the resolution of inflammation in HGF. Thus, our findings justify further investigations on the influence of probiotic bacteria on gingival inflammatory reactions.

  14. EVALUATION OF THE VIABILITY OF PLEUROTUS SPP. STRAINS AFTER LIQUID NITROGEN CRYOPRESERVATION

    Directory of Open Access Journals (Sweden)

    Lara-Herrera Isabel

    1998-01-01

    Full Text Available Viability of 6 mushroom strains of the Pleurotus genus (2 from P. djamor var. djamor, 1 from P. ostreatus var. ostreatus, 2 from P. ostreatus var. columbinus and 1 from P. pulmonarius after liquid nitrogen cryopreservation (-196º was evaluated. The contact time for the mycelia of these strains with the cryoprotectant (glycerol was studied 1, 2 and 3 hours before freezing. We also tested the effect of different times (5, 10 and 15 minutes and temperatures (30, 45 and 60ºC of the thawing system for mycelial recovery. The results showed a marked tendency toward faster mycelial recovery when samples were thawed at 30ºC, while at 60ºC no recovery was observed. A change in thawing and contact times with the cryoprotectant did not affect the results significantly, as the thawing temperature and strain employed affected.

  15. Altered arterial stiffness and subendocardial viability ratio in young healthy light smokers after acute exercise.

    Directory of Open Access Journals (Sweden)

    Robert J Doonan

    Full Text Available Studies showed that long-standing smokers have stiffer arteries at rest. However, the effect of smoking on the ability of the vascular system to respond to increased demands (physical stress has not been studied. The purpose of this study was to estimate the effect of smoking on arterial stiffness and subendocardial viability ratio, at rest and after acute exercise in young healthy individuals.Healthy light smokers (n = 24, pack-years = 2.9 and non-smokers (n = 53 underwent pulse wave analysis and carotid-femoral pulse wave velocity measurements at rest, and 2, 5, 10, and 15 minutes following an exercise test to exhaustion. Smokers were tested, 1 after 12h abstinence from smoking (chronic condition and 2 immediately after smoking one cigarette (acute condition. At rest, chronic smokers had higher augmentation index and lower aortic pulse pressure than non-smokers, while subendocardial viability ratio was not significantly different. Acute smoking increased resting augmentation index and decreased subendocardial viability ratio compared with non-smokers, and decreased subendocardial viability ratio compared with the chronic condition. After exercise, subendocardial viability ratio was lower, and augmentation index and aortic pulse pressure were higher in non-smokers than smokers in the chronic and acute conditions. cfPWV rate of recovery of was greater in non-smokers than chronic smokers after exercise. Non-smokers were also able to achieve higher workloads than smokers in both conditions.Chronic and acute smoking appears to diminish the vascular response to physical stress. This can be seen as an impaired 'vascular reserve' or a blunted ability of the blood vessels to accommodate the changes required to achieve higher workloads. These changes were noted before changes in arterial stiffness or subendocardial viability ratio occurred at rest. Even light smoking in young healthy individuals appears to have harmful effects on vascular

  16. Bacterial Acclimation Inside an Aqueous Battery.

    Science.gov (United States)

    Dong, Dexian; Chen, Baoling; Chen, P

    2015-01-01

    Specific environmental stresses may lead to induced genomic instability in bacteria, generating beneficial mutants and potentially accelerating the breeding of industrial microorganisms. The environmental stresses inside the aqueous battery may be derived from such conditions as ion shuttle, pH gradient, free radical reaction and electric field. In most industrial and medical applications, electric fields and direct currents are used to kill bacteria and yeast. However, the present study focused on increasing bacterial survival inside an operating battery. Using a bacterial acclimation strategy, both Escherichia coli and Bacillus subtilis were acclimated for 10 battery operation cycles and survived in the battery for over 3 days. The acclimated bacteria changed in cell shape, growth rate and colony color. Further analysis indicated that electrolyte concentration could be one of the major factors determining bacterial survival inside an aqueous battery. The acclimation process significantly improved the viability of both bacteria E. coli and B. subtilis. The viability of acclimated strains was not affected under battery cycle conditions of 0.18-0.80 mA cm(-2) and 1.4-2.1 V. Bacterial addition within 1.0×10(10) cells mL(-1) did not significantly affect battery performance. Because the environmental stress inside the aqueous battery is specific, the use of this battery acclimation strategy may be of great potential for the breeding of industrial microorganisms.

  17. Effect of kynurenic acid on the viability of probiotics in vitro.

    Science.gov (United States)

    Dolecka, Jadwiga; Urbanik-Sypniewska, Teresa; Skrzydło-Radomańska, Barbara; Parada-Turska, Jolanta

    2011-01-01

    Probiotics are bacteria that are commercially available as dietary supplements. One of the important properties of probiotics is their ability to survive in the intestine. Recent evidence has identified kynurenic acid (KYNA) as a bactericidal constituent of intestinal fluid. These data led us to study the influence of KYNA on the viability of selected probiotics. We found that KYNA supported the growth of bacteria in the probiotics Acidolac (Lactobacillus acidophilus, Bifidobacterium) and Lakcid Forte (Lactobacillus rhamnosus) or retarded the growth of bacteria from the Acidolac, BioGaia (Lactobacillus reuteri Protectis), Dicoflor (Lactobacillus rhamnosus GG), Lacium (Lactobacillus plantarum) and Trilac (Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, Bifidobacterium animalis subsp. lactis) probiotics depending on its concentration. KYNA did not affect the viability of bacteria from the probiotic Linex (Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12). Our results suggest a potential role of KYNA in the regulation of bacterial growth in the digestive system.

  18. Sustainable model for financial viability of decentralized biomass gasifier based power projects

    International Nuclear Information System (INIS)

    Palit, Debajit; Malhotra, Ramit; Kumar, Atul

    2011-01-01

    This paper made a modest attempt for designing a sustainable model for financial viability of biomass gasifier power projects for enhancing electricity access in India and other developing countries. For long term sustainability of distributed generation projects in remote rural areas, viability from both project implementing agency (PIA) and the end-users need to be ensured. The minimum required prices of electricity from both PIA and end-user perspective have been estimated. While for PIA the cost recovery is the key for viability, the affordability to pay the electricity cost is crucial for the end users. Analysis carried out in this paper on the basis of data obtained from operational projects implemented in India reveal that it is essential to operate the system at a higher capacity utilization factor. While this can be achieved though creating convergence with locally relevant economic activity, it is also observed that micro-enterprises cannot pay beyond a certain price of electricity to keep it sustainable. This paper sets forth a case for developing a regulatory mechanism to extend the tariff fixation for the projects and providing cross-subsidies to ensure long term sustainability of off-grid project. - Highlights: → We design sustainable financial model for viability of biomass gasifier projects. → Analysis based on field data obtained from operational projects in India. Estimated electricity pricing from both implementing agency and end-users perspective. → A regulatory mechanism for tariff fixation and cross subsidization is recommended.

  19. Echinococcus metacestode: in search of viability markers.

    Science.gov (United States)

    Gottstein, Bruno; Wang, Junhua; Blagosklonov, Oleg; Grenouillet, Frédéric; Millon, Laurence; Vuitton, Dominique A; Müller, Norbert

    2014-01-01

    Epidemiological studies have demonstrated that most humans infected with Echinococcus spp. exhibit resistance to disease. When infection leads to disease, the parasite is partially controlled by host immunity: in case of immunocompetence, the normal alveolar echinococcosis (AE) or cystic echinococcosis (CE) situation, the metacestode grows slowly, and first clinical signs appear years after infection; in case of impaired immunity (AIDS; other immunodeficiencies), uncontrolled proliferation of the metacestode leads to rapidly progressing disease. Assessing Echinococcus multilocularis viability in vivo following therapeutic interventions in AE patients may be of tremendous benefit when compared with the invasive procedures used to perform biopsies. Current options are F18-fluorodeoxyglucose-positron emission tomography (FDG-PET), which visualizes periparasitic inflammation due to the metabolic activity of the metacestode, and measurement of antibodies against recEm18, a viability-associated protein, that rapidly regresses upon metacestode inactivation. For Echinococcus granulosus, similar prognosis-associated follow-up parameters are still lacking but a few candidates may be listed. Other possible markers include functional and diffusion-weighted Magnetic Resonance Imaging (MRI), and measurement of products from the parasite (circulating antigens or DNA), and from the host (inflammation markers, cytokines, or chemokines). Even though some of them have been promising in pilot studies, none has been properly validated in an appropriate number of patients until now to be recommended for further use in clinical settings. There is therefore still a need to develop reliable tools for improved viability assessment to provide the sufficient information needed to reliably withdraw anti-parasite benzimidazole chemotherapy, and a basis for the development of new alternative therapeutic tools. © B. Gottstein et al., published by EDP Sciences, 2014.

  20. Rapid onsite assessment of spore viability.

    Energy Technology Data Exchange (ETDEWEB)

    Branda, Steven; Lane, Todd W.; VanderNoot, Victoria A.; Gaucher, Sara P.; Jokerst, Amanda S.

    2005-12-01

    This one year LDRD addresses problems of threat assessment and restoration of facilities following a bioterror incident like the incident that closed down mail facilities in late 2001. Facilities that are contaminated with pathogenic spores such as B. anthracis spores must be shut down while they are treated with a sporicidal agent and the effectiveness of the treatment is ascertained. This process involves measuring the viability of spore test strips, laid out in a grid throughout the facility; the CDC accepted methodologies require transporting the samples to a laboratory and carrying out a 48 hr outgrowth experiment. We proposed developing a technique that will ultimately lead to a fieldable microfluidic device that can rapidly assess (ideally less than 30 min) spore viability and effectiveness of sporicidal treatment, returning facilities to use in hours not days. The proposed method will determine viability of spores by detecting early protein synthesis after chemical germination. During this year, we established the feasibility of this approach and gathered preliminary results that should fuel a future more comprehensive effort. Such a proposal is currently under review with the NIH. Proteomic signatures of Bacillus spores and vegetative cells were assessed by both slab gel electrophoresis as well as microchip based gel electrophoresis employing sensitive laser-induced fluorescence detection. The conditions for germination using a number of chemical germinants were evaluated and optimized and the time course of protein synthesis was ascertained. Microseparations were carried out using both viable spores and spores inactivated by two different methods. A select number of the early synthesis proteins were digested into peptides for analysis by mass spectrometry.

  1. BACTERIAL PLASMIDS

    Directory of Open Access Journals (Sweden)

    Marina Dinic

    2007-12-01

    Full Text Available Plasmids, extrachromosomal DNA, were identified in bacteria pertaining to family of Enterobacteriacae for the very first time. After that, they were discovered in almost every single observed strain. The structure of plasmids is made of circular double chain DNA molecules which are replicated autonomously in a host cell. Their length may vary from few up to several hundred kilobase (kb. Among the bacteria, plasmids are mostly transferred horizontally by conjugation process. Plasmid replication process can be divided into three stages: initiation, elongation, and termination. The process involves DNA helicase I, DNA gyrase, DNA polymerase III, endonuclease, and ligase.Plasmids contain genes essential for plasmid function and their preservation in a host cell (the beginning and the control of replication. Some of them possess genes whichcontrol plasmid stability. There is a common opinion that plasmids are unnecessary fora growth of bacterial population and their vital functions; thus, in many cases they can be taken up or kicked out with no lethal effects to a plasmid host cell. However,there are numerous biological functions of bacteria related to plasmids. Plasmids identification and classification are based upon their genetic features which are presented permanently in all of them, and these are: abilities to preserve themselves in a host cell and to control a replication process. In this way, plasmids classification among incompatibility groups is performed. The method of replicon typing, which is based on genotype and not on phenotype characteristics, has the same results as in compatibility grouping.

  2. MODERN TECHNIQUES OF CERVICAL INSTRUMENTATION IN IMMATURE SKELETON: VIABILITY ASSESSMENT

    Directory of Open Access Journals (Sweden)

    Ayrana Soares Aires

    Full Text Available ABSTRACT Objective: This study describes the use of materials for modern cervical instrumentation, evaluating its viability in children and adolescents, and the techniques used in different cases. The efficacy of the techniques was analyzed through improvement of pain, maintenance of cervical range of motion, recovery of craniocervical stability, bone consolidation, and spinal stenosis in the postoperative follow-up. Method: Retrospective study of the clinical and radiological parameters of 27 patients aged two to 16 years with cervical spine diseases. Results: Two patients had chronic dislocation in C1-C2, one had congenital axis spondylolisthesis, two had congenital dislocation in C1-C2, three had tumors, one had kyphosis after laminectomy, one had post-infection kyphosis, one had fracture, 11 were syndromic with instabilities, and five had congenital cervical scoliosis. As to surgical approaches, two patients were transorally operated, three by anterior approach, 15 by posterior approach, two by anterior and posterior approaches, and five were treated in three stages (anterior, posterior and anterior approaches. Regarding the technique of cervical stabilization, seven patients were treated by Goel-Harms technique, two received Goel’s facet distraction, and three, Wright translaminar screws. There were complications in four cases. Two patients in the instrumentation of C1 lateral mass due to poor positioning, one with cerebrospinal fluid fistula and one with surgical wound infection. Conclusion: Modern cervical instrumentation in pediatric patients is a safe and effective technique for the treatment of cervical instability.

  3. Artificial evolution by viability rather than competition.

    Science.gov (United States)

    Maesani, Andrea; Fernando, Pradeep Ruben; Floreano, Dario

    2014-01-01

    Evolutionary algorithms are widespread heuristic methods inspired by natural evolution to solve difficult problems for which analytical approaches are not suitable. In many domains experimenters are not only interested in discovering optimal solutions, but also in finding the largest number of different solutions satisfying minimal requirements. However, the formulation of an effective performance measure describing these requirements, also known as fitness function, represents a major challenge. The difficulty of combining and weighting multiple problem objectives and constraints of possibly varying nature and scale into a single fitness function often leads to unsatisfactory solutions. Furthermore, selective reproduction of the fittest solutions, which is inspired by competition-based selection in nature, leads to loss of diversity within the evolving population and premature convergence of the algorithm, hindering the discovery of many different solutions. Here we present an alternative abstraction of artificial evolution, which does not require the formulation of a composite fitness function. Inspired from viability theory in dynamical systems, natural evolution and ethology, the proposed method puts emphasis on the elimination of individuals that do not meet a set of changing criteria, which are defined on the problem objectives and constraints. Experimental results show that the proposed method maintains higher diversity in the evolving population and generates more unique solutions when compared to classical competition-based evolutionary algorithms. Our findings suggest that incorporating viability principles into evolutionary algorithms can significantly improve the applicability and effectiveness of evolutionary methods to numerous complex problems of science and engineering, ranging from protein structure prediction to aircraft wing design.

  4. Concentration and Viability of Airborne Bacteria Over the Kuroshio Extension Region in the Northwestern Pacific Ocean: Data From Three Cruises

    Science.gov (United States)

    Hu, Wei; Murata, Kotaro; Fukuyama, Shinichiro; Kawai, Yoshimi; Oka, Eitarou; Uematsu, Mitsuo; Zhang, Daizhou

    2017-12-01

    Airborne bacteria have been shown to act as condensation and ice nuclei in mixed-phase clouds and are consequently hypothesized to have significant effects on atmospheric processes and even the global climate. However, few data are available regarding their concentration and variation in the air over the open ocean. Aerosol samples were collected during three cruises in the early summers of 2013, 2014, and 2016 over the Kuroshio Extension region of the northwest Pacific Ocean. The concentrations of viable and nonviable bacterial cells in the marine surface air were quantified using epifluorescence enumeration with the LIVE/DEAD BacLight stain. The concentrations of total bacteria varied between 1.0 × 104 and 2.5 × 105 cells m-3 and averaged 5.2 × 104, 1.0 × 105, and 7.5 × 104 cells m-3 in the three respective cruises. The viabilities, i.e., the ratios of the concentration of viable bacterial cells to that of total bacterial cells, ranged from 80% to 100% (average 93%), and the respective means were 93%, 89%, and 96% in the cruises. The total bacterial concentration had a close correlation with the wind speed near the sea surface, and the bacterial viability correlated negatively with the air temperature, sea surface temperature, and concentration of coarse particles (size > 1 μm). The deposition and sea spray fluxes of bacteria were roughly estimated as hundreds of cells m-2 s-1 on average. The limited data on bacterial concentration and viability from the three cruises indicate the rapid air-sea exchange of bacteria over the Kuroshio Extension region of the northwest Pacific Ocean.

  5. Usefulness of myocardial parametric imaging to evaluate myocardial viability in experimental and in clinical studies

    Science.gov (United States)

    Korosoglou, G; Hansen, A; Bekeredjian, R; Filusch, A; Hardt, S; Wolf, D; Schellberg, D; Katus, H A; Kuecherer, H

    2006-01-01

    Objective To evaluate whether myocardial parametric imaging (MPI) is superior to visual assessment for the evaluation of myocardial viability. Methods and results Myocardial contrast echocardiography (MCE) was assessed in 11 pigs before, during, and after left anterior descending coronary artery occlusion and in 32 patients with ischaemic heart disease by using intravenous SonoVue administration. In experimental studies perfusion defect area assessment by MPI was compared with visually guided perfusion defect planimetry. Histological assessment of necrotic tissue was the standard reference. In clinical studies viability was assessed on a segmental level by (1) visual analysis of myocardial opacification; (2) quantitative estimation of myocardial blood flow in regions of interest; and (3) MPI. Functional recovery between three and six months after revascularisation was the standard reference. In experimental studies, compared with visually guided perfusion defect planimetry, planimetric assessment of infarct size by MPI correlated more significantly with histology (r2  =  0.92 versus r2  =  0.56) and had a lower intraobserver variability (4% v 15%, p < 0.05). In clinical studies, MPI had higher specificity (66% v 43%, p < 0.05) than visual MCE and good accuracy (81%) for viability detection. It was less time consuming (3.4 (1.6) v 9.2 (2.4) minutes per image, p < 0.05) than quantitative blood flow estimation by regions of interest and increased the agreement between observers interpreting myocardial perfusion (κ  =  0.87 v κ  =  0.75, p < 0.05). Conclusion MPI is useful for the evaluation of myocardial viability both in animals and in patients. It is less time consuming than quantification analysis by regions of interest and less observer dependent than visual analysis. Thus, strategies incorporating this technique may be valuable for the evaluation of myocardial viability in clinical routine. PMID:15939722

  6. Demographic rates and population viability of black bears in Louisiana

    Science.gov (United States)

    Laufenberg, Jared S.; Clark, Joseph D.; Hooker, Michael J.; Lowe, Carrie L.; O'Connell-Goode, Kaitlin C.; Troxler, Jesse C.; Davidson, Maria M.; Chamberlain, Michael J.; Chandler, Richard B.

    2015-01-01

    The Louisiana black bear (Ursus americanus luteolus) was reduced to a few small, fragmented, and isolated subpopulations in the Lower Mississippi Alluvial Valley by the mid-twentieth century resulting from loss and fragmentation of habitat. In 1992, the United States Fish and Wildlife Service (USFWS) granted the Louisiana black bear threatened status under the United States Endangered Species Act of 1973. Since that time, a recovery plan was developed, a reintroduced population was established, and habitat recovery has occurred. The Recovery Plan states that a minimum of 2 populations must be viable (i.e., persistence probabilities over 100 years >0.95), 1 in the Tensas River Basin and 1 in the Atchafalaya River Basin. Consequently, our objectives were to 1) estimate demographic rates of Louisiana black bear subpopulations, 2) develop data-driven stochastic population projection models, and 3) determine how different projection model assumptions affect population trajectories and predictions about long-term persistence. Our overall goal was to assess long-term persistence of the bear subpopulations in Louisiana, individually and as a whole. We collected data using varying combinations of non-invasive DNA sampling, live capture, winter den visits, and radio monitoring from 2002 to 2012 in the 4 areas currently supporting breeding subpopulations in Louisiana: Tensas River Basin (TRB), Upper Atchafalaya River Basin (UARB), Lower Atchafalaya River Basin (LARB), and a recently reintroduced population at the Three Rivers Complex (TRC). From 2002 to 2012, we radio monitored fates of 86 adult females within the TRB and 43 in the TRC. Mean estimates of annual adult survival for the TRB and TRC were 0.997 and 0.990, respectively, when unknown fates were assumed alive and 0.970 and 0.926 when unknown fates were assumed dead. From 2003 to 2013, we observed 130 cub litters from 74 females in the TRB, and 74 cub litters from 45 females in the TRC. During the same period, we

  7. Exercise regulates breast cancer cell viability

    DEFF Research Database (Denmark)

    Dethlefsen, Christine; Lillelund, Christian; Midtgaard, Julie

    2016-01-01

    Purpose: Exercise decreases breast cancer risk and disease recurrence, but the underlying mechanisms are unknown. Training adaptations in systemic factors have been suggested as mediating causes. We aimed to examine if systemic adaptations to training over time, or acute exercise responses......, in breast cancer survivors could regulate breast cancer cell viability in vitro. Methods: Blood samples were collected from breast cancer survivors, partaking in either a 6-month training intervention or across a 2 h acute exercise session. Changes in training parameters and systemic factors were evaluated...... and pre/post exercise-conditioned sera from both studies were used to stimulate breast cancer cell lines (MCF-7, MDA-MB-231) in vitro. Results: Six months of training increased VO2peak (16.4 %, p

  8. Viability in holder of irradiated cells: distinguish between repair and cell multiplication

    International Nuclear Information System (INIS)

    Araujo, A.C. de.

    1980-01-01

    In experiments in which liquid holding recovery (LHR) was measured, the majority of cellular population is formed by non-viable cells and cell multiplication may be important for LHR expression. In order to distinguish between recuperation of viability (true LHR) and cell multiplication, it was necessary to employ improved plating techniques and a fluctuation test based on Poisson distribution. Our results are an indication that this fluctuation test, used together with the traditional method, is a good tool to distinguish repair from cell multiplication. (author)

  9. Immunologic reaction and viability of cryopreserved homografts.

    Science.gov (United States)

    Fischlein, T; Schütz, A; Haushofer, M; Frey, R; Uhlig, A; Detter, C; Reichart, B

    1995-08-01

    Homograft cell viability after cryopreservation was investigated and cytoimmunologic monitoring was performed during the early postoperative course to research possible immunologic reactions after allograft aortic valve replacement. After cryopreservation, morphologic observations were made, a nonradioactive cell proliferation assay was used, and prostaglandin I2 secretion of the remaining endothelial cells was determined. Cytoimmunologic monitoring was performed daily within the first 3 weeks postoperatively. An increase of the activation index greater than 1 was rated as an immunologic reaction. Maintained metabolic activity of graft endothelial cells after cryopreservation was confirmed by prostaglandin I2 release (9.24 +/- 3.48 ng/cm2 basic release and 20.1 +/- 5.76 ng/cm2 when stimulated with 25 mumol/L Na arachidonic acid). Cell proliferation was indicated after graft incubation with the nonradioactive viability kit (0.27 +/- 0.9 at 450 nm). Cytoimmunologic examinations (n = 861) after homograft implantation showed a more intense activation in patients with ABO-incompatible grafts (activation index 2.1 +/- 1.6, n = 16) than in those with ABO-compatible grafts (activation index 1.3 +/- 0.8, n = 17). In these groups, the duration of activation by cytoimmunologic monitoring was 2.8 +/- 1.5 days and 1.3 +/- 0.6 days, respectively (p < 0.041). No activation was observed in 8 patients after xenograft valve replacement (p < 0.01). Our data indicate that cryopreservation of homograft valves represents a cell- and tissue-protective preservation method. Postoperatively, all homograft valves caused immunologic reactions, which were reversible without immunosuppression treatment.

  10. Artificial evolution by viability rather than competition.

    Directory of Open Access Journals (Sweden)

    Andrea Maesani

    Full Text Available Evolutionary algorithms are widespread heuristic methods inspired by natural evolution to solve difficult problems for which analytical approaches are not suitable. In many domains experimenters are not only interested in discovering optimal solutions, but also in finding the largest number of different solutions satisfying minimal requirements. However, the formulation of an effective performance measure describing these requirements, also known as fitness function, represents a major challenge. The difficulty of combining and weighting multiple problem objectives and constraints of possibly varying nature and scale into a single fitness function often leads to unsatisfactory solutions. Furthermore, selective reproduction of the fittest solutions, which is inspired by competition-based selection in nature, leads to loss of diversity within the evolving population and premature convergence of the algorithm, hindering the discovery of many different solutions. Here we present an alternative abstraction of artificial evolution, which does not require the formulation of a composite fitness function. Inspired from viability theory in dynamical systems, natural evolution and ethology, the proposed method puts emphasis on the elimination of individuals that do not meet a set of changing criteria, which are defined on the problem objectives and constraints. Experimental results show that the proposed method maintains higher diversity in the evolving population and generates more unique solutions when compared to classical competition-based evolutionary algorithms. Our findings suggest that incorporating viability principles into evolutionary algorithms can significantly improve the applicability and effectiveness of evolutionary methods to numerous complex problems of science and engineering, ranging from protein structure prediction to aircraft wing design.

  11. Diagnosis of human preimplantation embryo viability.

    Science.gov (United States)

    Gardner, David K; Meseguer, Marcos; Rubio, Carmen; Treff, Nathan R

    2015-01-01

    Transfer of more than a single embryo in an IVF cycle comes with the finite possibility of a multiple gestation. Even a twin pregnancy confers significant risk to both mother and babies. The move to single-embryo transfer for all patients will be greatly facilitated by the ability to quantify embryo viability. Developments in time-lapse incubation systems have provided new insights into the developmental kinetics of the human preimplantation embryo. Advances in molecular methods of chromosomal analysis have created platforms for highly effective screening of biopsied embryos, while noninvasive analysis of embryo physiology reveals more about the embryo than can be determined by morphology alone. Recent developments in time-lapse microscopy, molecular karyotyping and in proteomics and metabolomics have been assessed and presented here in a descriptive review. New algorithms are being created for embryo selection based on their developmental kinetics in culture, and the impact of factors such as patient etiology and treatment are being clarified. Potential links between morphokinetic data and embryo karyotype are being elucidated. The introduction of new molecular methods of determining embryo chromosomal complement is proving to be accurate and reproducible, with the future trending toward CGH arrays or next generation sequencing as a rapid and reliable means of analysis, that should be suitable for each IVF clinic to adopt. A relationship between embryo metabolism and viability is established and is now being considered together with morphokinetic data to create more robust algorithms for embryo selection. Microfluidic devices have the capacity and potential to be used in human IVF clinics for the routine diagnosis of embryo biomarkers. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Probiotic viability and physico-chemical and sensory properties of plain and stirred fruit yogurts made from goat's milk.

    Science.gov (United States)

    Senaka Ranadheera, C; Evans, C A; Adams, M C; Baines, S K

    2012-12-01

    Probiotic plain and stirred fruit yogurts were made from goat's milk using bacterial cultures comprising, Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and Propionibacterium jensenii 702. The products were stored at 4°C for 4weeks, during which time the viability of the yogurt starter culture and probiotic bacteria was analysed weekly. P. jensenii 702 demonstrated the highest viability (10(8)cfu/g) in all types of yogurt throughout the storage period, while the viability of the bifidobacteria (∼10(7)cfu/g) also remained above the minimum therapeutic level. The viability of L. acidophilus LA-5 fell below 10(6)cfu/g in yogurts, however, the addition of fruit juice appeared to support the viability of lactobacilli, with higher microorganism numbers observed in fruit yogurts than in plain yogurt throughout the shelf life. Addition of fruit juice significantly increased the syneresis, and decreased viscosity and water holding capacity of yogurts (p<0.05), and also enhanced their sensory acceptability. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Sperm viability staining in ecology and evolution: potential pitfalls

    DEFF Research Database (Denmark)

    Holman, Luke

    2009-01-01

    The causes and consequences of variation in sperm quality, survival and ageing are active areas of research in ecology and evolution. In order to address these topics, many recent studies have measured sperm viability using fluorescent staining. Although sperm viability staining has produced...... a number of interesting results, it has some potential pitfalls that have rarely been discussed. In the present paper, I review the major findings of ecology and evolution studies employing sperm viability staining and outline the method's principle limitations. The key problem is that the viability assay...... may itself kill sperm, which is likely to confound many common experimental designs in addition to producing artificially low estimates of sperm viability. I further suggest that sperm number should be routinely measured in sperm viability studies, as it may be an important but overlooked source...

  14. Viability of Hybrid Systems A Controllability Operator Approach

    CERN Document Server

    Labinaz, G

    2012-01-01

    The problem of viability of hybrid systems is considered in this work. A model for a hybrid system is developed including a means of including three forms of uncertainty: transition dynamics, structural uncertainty, and parametric uncertainty. A computational basis for viability of hybrid systems is developed and applied to three control law classes. An approach is developed for robust viability based on two extensions of the controllability operator. The three-tank example is examined for both the viability problem and robust viability problem. The theory is applied through simulation to an active magnetic bearing system and to a batch polymerization process showing that viability can be satisfied in practice. The problem of viable attainability is examined based on the controllability operator approach introduced by Nerode and colleagues. Lastly, properties of the controllability operator are presented.

  15. Achado de bactérias selecionadas em crianças de Trinidad com doença amigdaliana crônica Selected bacterial recovery in Trinidadian children with chronic tonsillar disease

    Directory of Open Access Journals (Sweden)

    Lexley Maureen Pinto Pereira

    2008-12-01

    Full Text Available Faringoamigdalite na população pediátrica é largamente tratada com antibióticos. OBJETIVO: Estudar a microflora presente na superfície e no núcleo de amígdalas após adenoamigdalectomia eletiva em crianças. MÉTODO: Amígdalas de 102 crianças de Trinidad foram prospectivamente estudadas por meio de culturas e identificações bacteriológicas feitas a partir de amostras das superfícies e núcleos de suas amígdalas entre 2005-2006. RESULTADOS: A partir de 360 amígdalas, foram isolados Streptococcus spp. (51,3%, Staphylococcus spp. (42,3% e Gram-Negativos (6,4%. A identificação de estafilococos e estreptococos tanto na superfície quanto no núcleo foi semelhante (p>0,05. Encontramos mais (pPharyngotonsillitis in children is widely treated with antibiotics. AIM: To examine tonsil surface and core microflora following elective adenotonsillectomy in children. METHODS: Tonsils of 102 Trinidadian children were prospectively examined for surface and core bacteriological culture and identification between 2005-2006. RESULTS: Tonsils (360 yielded 800 isolates of Streptococcus spp. (51.3%, Staphylococcus spp. (42.3% and Gram-negative genera (6.4%. Surface and core recovery of staphylococci and streptococci were similar (p>0.05. More (p<0.001 surfaces (82.2% than cores (63.3% grew Streptococcus spp.; α-haemolytic Streptococcus prevalence was higher (p<0.001 than ß-haemolytic Streptococcus on surfaces (74.4% vs. 18.6% than cores (58.9% vs. 13.7%. Surfaces and cores were not concordant for streptococci (p<0.0004 and α-haemolytic Streptococcus (p<0.007. Surface and core ß-haemolytic Streptococcus yield was higher (p<0.05 in 6-16 than 1-5 year olds (31% and 23.8% vs 12.5% and 8%. S. pyogenes surface and core prevalence was (84.6% vs 70% and (50.0% vs 25.0% in older and younger children respectively. Klebsiella spp. (6.6 %, 2.2%, Proteus (4.4%, 4.4% and Pseudomonas (4.4 %, 1.1% grew on surfaces and cores respectively. CONCLUSION: Tonsil

  16. Effect of gamma irradiation on viability and DNA of Staphylococcus epidermidis and Escherichia coli.

    Science.gov (United States)

    Trampuz, Andrej; Piper, Kerryl E; Steckelberg, James M; Patel, Robin

    2006-09-01

    Gamma irradiation is widely used for sterilization; however, its effect on elimination of amplifiable DNA, an issue of relevance to molecular diagnostic approaches, has not been well studied. The effect of gamma irradiation on the viability of Staphylococcus epidermidis and Escherichia coli (using quantitative cultures) and on their DNA (using quantitative 16S rRNA gene PCR) was evaluated. Viability was abrogated at 2.8 and 3.6 kGy for S. epidermidis and E. coli, respectively. The radiation dose required to reduce viable bacteria by one log10 (D10 value) was 0.31 and 0.35 kGy for S. epidermidis and E. coli, respectively. D10 values for amplifiable DNA extracted from bacteria were 2.58 and 3.09 kGy for S. epidermidis and E. coli, respectively, whereas D10 values for amplifiable DNA were significantly higher for DNA extracted from irradiated viable bacterial cells (22.9 and 52.6 kGy for S. epidermidis and E. coli, respectively; Pgamma irradiation of DNA in viable bacterial cells has little effect on amplifiable DNA, was not able to eliminate amplifiable 16S rRNA genes at a dose of up to 12 kGy and cannot therefore be used for elimination of DNA contamination of PCR reaction components or laboratory equipment when this DNA is present in microbial cells. This finding has practical implications for those using molecular diagnostic techniques in microbiology.

  17. Storage Viability and Optimization Web Service

    Energy Technology Data Exchange (ETDEWEB)

    Stadler, Michael; Marnay, Christ; Lai, Judy; Siddiqui, Afzal; Limpaitoon, Tanachai; Phan, Trucy; Megel, Olivier; Chang, Jessica; DeForest, Nicholas

    2010-10-11

    Non-residential sectors offer many promising applications for electrical storage (batteries) and photovoltaics (PVs). However, choosing and operating storage under complex tariff structures poses a daunting technical and economic problem that may discourage potential customers and result in lost carbon and economic savings. Equipment vendors are unlikely to provide adequate environmental analysis or unbiased economic results to potential clients, and are even less likely to completely describe the robustness of choices in the face of changing fuel prices and tariffs. Given these considerations, researchers at Lawrence Berkeley National Laboratory (LBNL) have designed the Storage Viability and Optimization Web Service (SVOW): a tool that helps building owners, operators and managers to decide if storage technologies and PVs merit deeper analysis. SVOW is an open access, web-based energy storage and PV analysis calculator, accessible by secure remote login. Upon first login, the user sees an overview of the parameters: load profile, tariff, technologies, and solar radiation location. Each parameter has a pull-down list of possible predefined inputs and users may upload their own as necessary. Since the non-residential sectors encompass a broad range of facilities with fundamentally different characteristics, the tool starts by asking the users to select a load profile from a limited cohort group of example facilities. The example facilities are categorized according to their North American Industry Classification System (NAICS) code. After the load profile selection, users select a predefined tariff or use the widget to create their own. The technologies and solar radiation menus operate in a similar fashion. After these four parameters have been inputted, the users have to select an optimization setting as well as an optimization objective. The analytic engine of SVOW is LBNL?s Distributed Energy Resources Customer Adoption Model (DER-CAM), which is a mixed

  18. The influence of nanoscopically thin silver films on bacterial viability and attachment.

    Science.gov (United States)

    Ivanova, Elena P; Hasan, Jafar; Truong, Vi Khanh; Wang, James Y; Raveggi, Massimo; Fluke, Christopher; Crawford, Russell J

    2011-08-01

    The physicochemical and bactericidal properties of thin silver films have been analysed. Silver films of 3 and 150 nm thicknesses were fabricated using a magnetron sputtering thin-film deposition system. X-ray photoelectron and energy dispersive X-ray spectroscopy and atomic force microscopy analyses confirmed that the resulting surfaces were homogeneous, and that silver was the most abundant element present on both surfaces, being 45 and 53 at.% on the 3- and 150-nm films, respectively. Inductively coupled plasma time of flight mass spectroscopy (ICP-TOF-MS) was used to measure the concentration of silver ions released from these films. Concentrations of 0.9 and 5.2 ppb were detected for the 3- and 150-nm films, respectively. The surface wettability of the films remained nearly identical for both film thicknesses, displaying a static water contact angle of 95°, while the surface free energy of the 150-nm film was found to be slightly greater than that of the 3-nm film, being 28.8 and 23.9 mN m(-1), respectively. The two silver film thicknesses exhibited statistically significant differences in surface topographic profiles on the nanoscopic scale, with R (a), R (q) and R (max) values of 1.4, 1.8 and 15.4 nm for the 3-nm film and 0.8, 1.2 and 10.7 nm for the 150-nm film over a 5 × 5 μm scanning area. Confocal scanning laser microscopy and scanning electron microscopy revealed that the bactericidal activity of the 3-nm silver film was not significant, whereas the nanoscopically smoother 150-nm silver film exhibited appreciable bactericidal activity towards Pseudomonas aeruginosa ATCC 9027 cells and Staphylococcus aureus CIP 65.8 cells, obtaining up to 75% and 27% sterilisation effect, respectively.

  19. Assessment of viability in the bacterial standing stock of the Antarctic Sea from the Indian side

    Digital Repository Service at National Institute of Oceanography (India)

    LokaBharathi, P.A.; Nair, S.; DeSouza, M.J.B.D.; Chandramohan, D.

    at station 9, and at 100 m at station 8 may be due to either the patchy distribution of bacteria or effect of algal blooms (Bouvy and Delille, 1988). The TVC and RC are also of great assistance in understanding the influence of active fraction density...

  20. Cardiac 99mTc sestamibi SPECT and 18F FDG PET as viability markers in takotsubo cardiomyopathy

    DEFF Research Database (Denmark)

    Christensen, Thomas Emil; Bang, Lia Evi; Holmvang, Lene

    2014-01-01

    , "apical ballooning" and a perfusion-metabolism defect in the midventricular/apical region. When viability criteria were applied, they identified significant scarring/limited hibernation in the akinetic part of the left ventricle. However, full recovery was found in all TTC patients on follow-up. Using...

  1. Bacterial Biofilms in Jones Tubes.

    Science.gov (United States)

    Ahn, Eric S; Hauck, Matthew J; Kirk Harris, Jonathan; Robertson, Charles E; Dailey, Roger A

    To investigate the presence and microbiology of bacterial biofilms on Jones tubes (JTs) by direct visualization with scanning electron microscopy and polymerase chain reaction (PCR) of representative JTs, and to correlate these findings with inflammation and/or infection related to the JT. In this study, prospective case series were performed. JTs were recovered from consecutive patients presenting to clinic for routine cleaning or recurrent irritation/infection. Four tubes were processed for scanning electron microscopy alone to visualize evidence of biofilms. Two tubes underwent PCR alone for bacterial quantification. One tube was divided in half and sent for scanning electron microscopy and PCR. Symptoms related to the JTs were recorded at the time of recovery. Seven tubes were obtained. Five underwent SEM, and 3 out of 5 showed evidence of biofilms (60%). Two of the 3 biofilms demonstrated cocci and the third revealed rods. Three tubes underwent PCR. The predominant bacteria identified were Pseudomonadales (39%), Pseudomonas (16%), and Staphylococcus (14%). Three of the 7 patients (43%) reported irritation and discharge at presentation. Two symptomatic patients, whose tubes were imaged only, revealed biofilms. The third symptomatic patient's tube underwent PCR only, showing predominantly Staphylococcus (56%) and Haemophilus (36%) species. Two of the 4 asymptomatic patients also showed biofilms. All symptomatic patients improved rapidly after tube exchange and steroid antibiotic drops. Bacterial biofilms were variably present on JTs, and did not always correlate with patients' symptoms. Nevertheless, routine JT cleaning is recommended to treat and possibly prevent inflammation caused by biofilms.

  2. Developing the tissue viability seating guidelines.

    Science.gov (United States)

    Stephens, Melanie; Bartley, Carol; Betteridge, Ria; Samuriwo, Ray

    2018-02-01

    Costs for the prevention and management of pressure ulcers have increased significantly with limited published advice from health and social care organisations on seating and preventing pressure ulcers. At the request of the UK Tissue Viability Society the aim of the publication was to develop a practical guide for people, carers and health and social care professionals on how the research and evidence base on pressure ulcer prevention and management can be applied to those who remain seated for extended periods of time. The evidence base informing the guidelines was obtained by applying a triangulation of methods: a literature review, listening event and stakeholder group consultation. The purpose was to engage users and carers, academics, clinicians, inspectorate and charities, with an interest in seating, positioning and pressure management to: gather views, feedback, stories, and evidence of the current practices in the field to create a greater awareness of the issue. The new guidelines are inclusive of all people with short and long-term mobility issues to include all population groups. The document includes evidence on where pressure ulcers develop when seated, risk factors, best possible seated position and what seat adjustments are required, the ideal seating assessment, interventions, self-help suggestions and key seating outcomes. The updated TVS CPGs have been informed by the best available evidence, the insights and wisdom of experts, stakeholders and people who spend extended periods of time sitting. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Functional viability profiles of breast cancer.

    Science.gov (United States)

    Brough, Rachel; Frankum, Jessica R; Sims, David; Mackay, Alan; Mendes-Pereira, Ana M; Bajrami, Ilirjana; Costa-Cabral, Sara; Rafiq, Rumana; Ahmad, Amar S; Cerone, Maria Antonietta; Natrajan, Rachael; Sharpe, Rachel; Shiu, Kai-Keen; Wetterskog, Daniel; Dedes, Konstantine J; Lambros, Maryou B; Rawjee, Teeara; Linardopoulos, Spiros; Reis-Filho, Jorge S; Turner, Nicholas C; Lord, Christopher J; Ashworth, Alan

    2011-08-01

    The design of targeted therapeutic strategies for cancer has largely been driven by the identification of tumor-specific genetic changes. However, the large number of genetic alterations present in tumor cells means that it is difficult to discriminate between genes that are critical for maintaining the disease state and those that are merely coincidental. Even when critical genes can be identified, directly targeting these is often challenging, meaning that alternative strategies such as exploiting synthetic lethality may be beneficial. To address these issues, we have carried out a functional genetic screen in >30 commonly used models of breast cancer to identify genes critical to the growth of specific breast cancer subtypes. In particular, we describe potential new therapeutic targets for PTEN-mutated cancers and for estrogen receptor-positive breast cancers. We also show that large-scale functional profiling allows the classification of breast cancers into subgroups distinct from established subtypes. Despite the wealth of molecular profiling data that describe breast tumors and breast tumor cell models, our understanding of the fundamental genetic dependencies in this disease is relatively poor. Using high-throughput RNA interference screening of a series of pharmacologically tractable genes, we have generated comprehensive functional viability profiles for a wide panel of commonly used breast tumor cell models. Analysis of these profiles identifies a series of novel genetic dependencies, including that of PTEN-null breast tumor cells upon mitotic checkpoint kinases, and provides a framework upon which additional dependencies and candidate therapeutic targets may be identified.

  4. Algae viability over time in a ballast water sample

    Science.gov (United States)

    Gollasch, Stephan; David, Matej

    2018-03-01

    The biology of vessels' ballast water needs to be analysed for several reasons, one of these being performance tests of ballast water management systems. This analysis includes a viability assessment of phytoplankton. To overcome logistical problems to get algae sample processing gear on board of a vessel to document algae viability, samples may be transported to land-based laboratories. Concerns were raised how the storage conditions of the sample may impact algae viability over time and what the most appropriate storage conditions were. Here we answer these questions with a long-term algae viability study with daily sample analysis using Pulse-Amplitude Modulated (PAM) fluorometry. The sample was analysed over 79 days. We tested different storage conditions: fridge and room temperature with and without light. It seems that during the first two weeks of the experiment the viability remains almost unchanged with a slight downwards trend. In the continuing period, before the sample was split, a slightly stronger downwards viability trend was observed, which occurred at a similar rate towards the end of the experiment. After the sample was split, the strongest viability reduction was measured for the sample stored without light at room temperature. We concluded that the storage conditions, especially regarding temperature and light exposure, have a stronger impact on algae viability compared to the storage duration and that inappropriate storage conditions reduce algal viability. A sample storage time of up to two weeks in a dark and cool environment has little influence on the organism viability. This indicates that a two week time duration between sample taking on board a vessel and the viability measurement in a land-based laboratory may not be very critical.

  5. Intra-inflorescence pollen viability in accessions of Brachiaria ruziziensis

    Directory of Open Access Journals (Sweden)

    Cristina Maria Pinto de Paula

    2014-05-01

    Full Text Available Knowledge about the pollen viability is important to ensure success in controlled hybridizations and, consequently, support breeding programs. The aims of this study were to evaluate the pollen viability in progenies of artificially induced tetraploid accessions of Brachiaria ruziziensis, and to verify if the position of the flower buds on the raceme affects the pollen viability rate. Staining of aborted and non-aborted pollen (Alexander’s technique was used to determine the viability of the pollen grains. Tetraploid accessions of B. ruziziensis plants had high pollen viability (x = 76.8% to x = 99.6%. Some of these plants had viability rates similar to diploid B. ruziziensis, showing that the induction of chromosome duplication by colchicine did not result in abnormalities in production and morphology of pollen grains. Pollen grains from middle and apical regions of the raceme presented higher viability rates (x = 97.9% and x = 97.7% respectively. The viability of pollen grains in artificially induced tetraploid accessions of B. ruziziensis plants was high, which may favor obtaining fertile descendants in possible crosses

  6. Evaluation of pollen viability, stigma receptivity and fertilization ...

    African Journals Online (AJOL)

    To provide theoretical basis for artificial pollination in Lagerstroemia indica L., pollen viability and stigma receptivity were tested and the morphological change of stigma was observed. Pollen viability tested by in vitro culture, stigma receptivity examined by benzidine-H2O2 testing and fruit set estimated by field artificial ...

  7. Seed viability, germination and seedling growth of canola (Brassica ...

    African Journals Online (AJOL)

    Jane

    2011-10-03

    Oct 3, 2011 ... investigated. The effect of mutagen dosage on seed viability was also assessed using the tetrazolium staining test. Results revealed the significant effects of mutagen dosages and treatment periods on seed viability and seed germination as well as on seedling characteristics for all the mutagens tested.

  8. Viability, Advantages and Design Methodologies of M-Learning Delivery

    Science.gov (United States)

    Zabel, Todd W.

    2010-01-01

    The purpose of this study was to examine the viability and principle design methodologies of Mobile Learning models in developing regions. Demographic and market studies were utilized to determine the viability of M-Learning delivery as well as best uses for such technologies and methods given socioeconomic and political conditions within the…

  9. Pollen viability and germination in Jatropha ribifolia and Jatropha ...

    African Journals Online (AJOL)

    The aim of this work is to assess pollen viability using the staining technique and in vitro germination with different concentrations of sucrose in Jatropha ribifolia and Jatropha mollissima, contributing to the knowledge of the reproductive biology and subsidizing their conservation, management and utilization. Pollen viability ...

  10. The relationship of storage and viability of Lily pollen

    NARCIS (Netherlands)

    Rhee, H.K.; Lim, Jin Hee; Cho, Hae Ryong; Tuyl, van J.M.

    2003-01-01

    The study was conducted to estimate the pollen viability of eight lily genotypes and optimum storage conditions. Pollen viability was assessed by in vitro germination, FCR (Fluorochromatic raction) test and fruit set test. Pollen grains were stored in the dark chamber where the temperature was

  11. Viability of dielectrophoretically trapped neuronal cortical cells in culture

    NARCIS (Netherlands)

    Heida, Tjitske; Vulto, P; Rutten, Wim; Marani, Enrico

    2001-01-01

    Negative dielectrophoretic trapping of neural cells is an efficient way to position neural cells on the electrode sites of planar micro-electrode arrays. The preservation of viability of the neural cells is essential for this approach. This study investigates the viability of postnatal cortical rat

  12. Assessment of tissue viability by polarization spectroscopy

    Science.gov (United States)

    Nilsson, G.; Anderson, C.; Henricson, J.; Leahy, M.; O'Doherty, J.; Sjöberg, F.

    2008-09-01

    A new and versatile method for tissue viability imaging based on polarization spectroscopy of blood in superficial tissue structures such as the skin is presented in this paper. Linearly polarized light in the visible wavelength region is partly reflected directly by the skin surface and partly diffusely backscattered from the dermal tissue matrix. Most of the directly reflected light preserves its polarization state while the light returning from the deeper tissue layers is depolarized. By the use of a polarization filter positioned in front of a sensitive CCD-array, the light directly reflected from the tissue surface is blocked, while the depolarized light returning from the deeper tissue layers reaches the detector array. By separating the colour planes of the detected image, spectroscopic information about the amount of red blood cells (RBCs) in the microvascular network of the tissue under investigation can be derived. A theory that utilizes the differences in light absorption of RBCs and bloodless tissue in the red and green wavelength region forms the basis of an algorithm for displaying a colour coded map of the RBC distribution in a tissue. Using a fluid model, a linear relationship (cc. = 0.99) between RBC concentration and the output signal was demonstrated within the physiological range 0-4%. In-vivo evaluation using transepidermal application of acetylcholine by the way of iontophoresis displayed the heterogeneity pattern of the vasodilatation produced by the vasoactive agent. Applications of this novel technology are likely to be found in drug and skin care product development as well as in the assessment of skin irritation and tissue repair processes and even ultimately in a clinic case situation.

  13. Population viability analysis for endangered Roanoke logperch

    Science.gov (United States)

    Roberts, James H.; Angermeier, Paul; Anderson, Gregory B.

    2016-01-01

    A common strategy for recovering endangered species is ensuring that populations exceed the minimum viable population size (MVP), a demographic benchmark that theoretically ensures low long-term extinction risk. One method of establishing MVP is population viability analysis, a modeling technique that simulates population trajectories and forecasts extinction risk based on a series of biological, environmental, and management assumptions. Such models also help identify key uncertainties that have a large influence on extinction risk. We used stochastic count-based simulation models to explore extinction risk, MVP, and the possible benefits of alternative management strategies in populations of Roanoke logperch Percina rex, an endangered stream fish. Estimates of extinction risk were sensitive to the assumed population growth rate and model type, carrying capacity, and catastrophe regime (frequency and severity of anthropogenic fish kills), whereas demographic augmentation did little to reduce extinction risk. Under density-dependent growth, the estimated MVP for Roanoke logperch ranged from 200 to 4200 individuals, depending on the assumed severity of catastrophes. Thus, depending on the MVP threshold, anywhere from two to all five of the logperch populations we assessed were projected to be viable. Despite this uncertainty, these results help identify populations with the greatest relative extinction risk, as well as management strategies that might reduce this risk the most, such as increasing carrying capacity and reducing fish kills. Better estimates of population growth parameters and catastrophe regimes would facilitate the refinement of MVP and extinction-risk estimates, and they should be a high priority for future research on Roanoke logperch and other imperiled stream-fish species.

  14. Probing bacterial adhesion at the single-cell level

    DEFF Research Database (Denmark)

    Zeng, Guanghong; Müller, Torsten; Meyer, Rikke Louise

    Bacteria initiate attachment to surfaces with the aid of different extracellular proteins and polymeric adhesins. To quantitatively analyse the cell-cell and cell-surface interactions provided by bacterial adhesins, it is essential to go down to single cell level where cell-to-cell variation can...... be considered. We have developed a simple and versatile method to make single-cell bacterial probes for measuring single cell adhesion by force spectroscopy using atomic force microscopy (AFM). A single-cell probe was readily made by picking up a bacterial cell from a glass surface by approaching a tipless AFM...... cantilever coated with the commercial cell adhesive CellTakTM. We applied the method to study adhesion of living cells to abiotic surfaces at the single-cell level. Immobilisation of single bacterial cells to the cantilever was stable for several hours, and viability was confirmed by Live/Dead staining...

  15. Effect of smokeless tobacco products on human oral bacteria growth and viability

    Science.gov (United States)

    Liu, Min; Jin, Jinshan; Pan, Hongmiao; Feng, Jinhui; Cerniglia, Carl E.; Yang, Maocheng; Chen, Huizhong

    2017-01-01

    To evaluate the toxicity of smokeless tobacco products (STPs) on oral bacteria, seven smokeless tobacco aqueous extracts (STAEs) from major brands of STPs and three tobacco-specific N-nitrosamines (TSNAs) were used in a growth and viability test against 38 oral bacterial species or subspecies. All seven STAEs showed concentration-dependent effects on the growth and viability of tested oral bacteria under anaerobic culture conditions, although there were strain-to-strain variations. In the presence of 1 mg/ml STAEs, the growth of 4 strains decreased over 0.32–2.14 log10 fold, while 14 strains demonstrated enhanced growth of 0.3–1.76 log10 fold, and the growth of 21 strains was not significantly affected. In the presence of 10 mg/ml STAEs, the growth of 17 strains was inhibited 0.3–2.11 log10 fold, 18 strains showed enhanced growth of 0.3–0.97 log10 fold, and 4 strains were not significantly affected. In the presence of 50 mg/ml STAEs, the growth of 32 strains was inhibited 0.3–2.96 log10 fold, 8 strains showed enhanced growth of 0.3–1.0 log10 fold, and 2 strains were not significantly affected. All seven STAEs could promote the growth of 4 bacterial strains, including Eubacterium nodatum, Peptostreptococcus micros, Streptococcus anginosus, and Streptococcus constellatus. Exposure to STAEs modulated the viability of some bacterial strains, with 21.1–66.5% decrease for 4 strains at 1 mg/ml, 20.3–85.7% decrease for 10 strains at 10 mg/ml, 20.0–93.3% decrease for 27 strains at 50 mg/ml, and no significant effect for 11 strains at up to 50 mg/ml. STAEs from snuffs inhibited more tested bacterial strains than those from snus indicating that the snuffs may be more toxic to the oral bacteria than snus. For TSNAs, cell growth and viability of 34 tested strains were not significantly affected at up to 100 μg/ml; while the growth of P. micros was enhanced 0.31–0.54 log10 fold; the growth of Veillonella parvula was repressed 0.33–0.36 log10 fold; and the

  16. The effect of temperature and bacterial growth phase on protein extraction by means of electroporation.

    Science.gov (United States)

    Haberl-Meglič, Saša; Levičnik, Eva; Luengo, Elisa; Raso, Javier; Miklavčič, Damijan

    2016-12-01

    Different chemical and physical methods are used for extraction of proteins from bacteria, which are used in variety of fields. But on a large scale, many methods have severe drawbacks. Recently, extraction by means of electroporation showed a great potential to quickly obtain proteins from bacteria. Since many parameters are affecting the yield of extracted proteins, our aim was to investigate the effect of temperature and bacterial growth phase on the yield of extracted proteins. At the same time bacterial viability was tested. Our results showed that the temperature has a great effect on protein extraction, the best temperature post treatment being 4°C. No effect on bacterial viability was observed for all temperatures tested. Also bacterial growth phase did not affect the yield of extracted proteins or bacterial viability. Nevertheless, further experiments may need to be performed to confirm this observation, since only one incubation temperature (4°C) and one incubation time before and after electroporation (0.5 and 1h) were tested for bacterial growth phase. Based on our results we conclude that temperature is a key element for bacterial membrane to stay in a permeabilized state, so more proteins flow out of bacteria into surrounding media. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Prevention of bacterial adhesion

    DEFF Research Database (Denmark)

    Klemm, Per; Vejborg, Rebecca Munk; Hancock, Viktoria

    2010-01-01

    Management of bacterial infections is becoming increasingly difficult due to the emergence and increasing prevalence of bacterial pathogens that are resistant to available antibiotics. Conventional antibiotics generally kill bacteria by interfering with vital cellular functions, an approach...... that imposes selection pressure for resistant bacteria. New approaches are urgently needed. Targeting bacterial virulence functions directly is an attractive alternative. An obvious target is bacterial adhesion. Bacterial adhesion to surfaces is the first step in colonization, invasion, and biofilm formation....... As such, adhesion represents the Achilles heel of crucial pathogenic functions. It follows that interference with adhesion can reduce bacterial virulence. Here, we illustrate this important topic with examples of techniques being developed that can inhibit bacterial adhesion. Some of these will become...

  18. Preventing bacterial growth on implanted device with an interfacial metallic film and penetrating X-rays.

    Science.gov (United States)

    An, Jincui; Sun, An; Qiao, Yong; Zhang, Peipei; Su, Ming

    2015-02-01

    Device-related infections have been a big problem for a long time. This paper describes a new method to inhibit bacterial growth on implanted device with tissue-penetrating X-ray radiation, where a thin metallic film deposited on the device is used as a radio-sensitizing film for bacterial inhibition. At a given dose of X-ray, the bacterial viability decreases as the thickness of metal film (bismuth) increases. The bacterial viability decreases with X-ray dose increases. At X-ray dose of 2.5 Gy, 98% of bacteria on 10 nm thick bismuth film are killed; while it is only 25% of bacteria are killed on the bare petri dish. The same dose of X-ray kills 8% fibroblast cells that are within a short distance from bismuth film (4 mm). These results suggest that penetrating X-rays can kill bacteria on bismuth thin film deposited on surface of implant device efficiently.

  19. Lack of cations in flow cytometry buffers affect fluorescence signals by reducing membrane stability and viability of Escherichia coli strains.

    Science.gov (United States)

    Tomasek, Kathrin; Bergmiller, Tobias; Guet, Călin C

    2018-02-20

    Buffers are essential for diluting bacterial cultures for flow cytometry analysis in order to study bacterial physiology and gene expression parameters based on fluorescence signals. Using a variety of constitutively expressed fluorescent proteins in Escherichia coli K-12 strain MG1655, we found strong artifactual changes in fluorescence levels after dilution into the commonly used flow cytometry buffer phosphate-buffered saline (PBS) and two other buffer solutions, Tris-HCl and M9 salts. These changes appeared very rapidly after dilution, and were linked to increased membrane permeability and loss in cell viability. We observed buffer-related effects in several different E. coli strains, K-12, C and W, but not E. coli B, which can be partially explained by differences in lipopolysaccharide (LPS) and outer membrane composition. Supplementing the buffers with divalent cations responsible for outer membrane stability, Mg 2+ and Ca 2+ , preserved fluorescence signals, membrane integrity and viability of E. coli. Thus, stabilizing the bacterial outer membrane is essential for precise and unbiased measurements of fluorescence parameters using flow cytometry. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Evaluation of ischemic heart disease on a 1.5 Tesla scanner. Combined first-pass perfusion and viability study

    International Nuclear Information System (INIS)

    Okuda, Shigeo; Tanimoto, Akihiro; Satoh, Toru; Hashimoto, Jun; Shinmoto, Hiroshi; Higuchi, Nobuya; Kuribayashi, Sachio

    2005-01-01

    We implemented a fast gradient echo (GRE) sequence with an echo-planar imaging (EPI) read-out (FGRE-ET) to conduct myocardial perfusion studies on a conventional scanner. The accuracy of combined perfusion and viability studies is evaluated in comparison with coronary angiography (CAG). We enrolled 33 patients suspected of having coronary artery disease in this study. Short-axis perfusion images of the left ventricles were acquired following intravenous bolus injection of gadolinium-DTPA (0.05 mml/kg), both after myocardial loading by dipyridamole (0.56 mg/kg) and at rest. Viability studies were obtained using an inversion-recovery FGRE sequence. Radiologists performed blinded film readings. The findings with perfusion and the viability studies were compared with CAG on a segment-to-segment basis corresponding to the coronary arteries' territories. Stenosis equal to or greater than 75% in diameter was considered significant on CAG. The results were also compared with single photon emission computed tomography (SPECT) in 23 patients. The combination of perfusion and viability studies showed 85.7% sensitivity, 88.9% specificity, and 87.2% accuracy in comparison with CAG. SPECT revealed respective rates of 71.7%, 78.3%, and 73.9% in 23 patients of this group. Myocardial perfusion studies using EGRE-ET were feasible and accurate, even on a conventional scanner. (author)

  1. Cadmium affects the mitochondrial viability and the acid soluble ...

    African Journals Online (AJOL)

    Cadmium affects the mitochondrial viability and the acid soluble thiols concentration in liver, kidney, heart and gills of Ancistrus brevifilis (Eigenmann, 1920). P Velasquez-Vottelerd, Y Anton, R Salazar-Lugo ...

  2. STUDY ON POLLEN VIABILITY AS BIOINDICATOR OF AIR QUALITY

    Directory of Open Access Journals (Sweden)

    Florentina ŞTEFLEA

    2012-01-01

    Full Text Available The aim of this research is to estimate the relationship between pollen viability and atmospheric pollution (in polluted and non-polluted conditions. The study was carried out in the city of Timisoara. Two areas, with different intensity of road traffic (very high and absent but all characterized by the presence of the same plant species, were selected. The pollen of herbaceous spontaneous species, arboreal species and a shrub species was used (Robinia pseudacacia, Aesculus x carnea, Catalpa bignonioides, Albizzia julibrissin, Rosa canina, Sambucus nigra, Malva neglecta, Ranunculus acer, Trifolium repens, Cichorium intybus. The pollen of these species was treated with TTC (2, 3, 5 Tryphenil-Tetrazolium-Chloride staining solution and viability was then estimated by light microscopy. The results of the mean pollen viability percentage of the examined species are reported. Pollen viability of herbaceous plants is significantly different between the two environments.

  3. Equine ovarian tissue viability after cryopreservation and in vitro culture

    Science.gov (United States)

    The efficiency of several cryoprotective agents were compared using both slow-freezing and vitrification methods. Results indicate that the viability of ovarian tissue cells increases when DMSO (slow-freezing) and ethylene glycol (vitrification) are used....

  4. Probiotic fermented sausage: viability of probiotic microorganisms and sensory characteristics.

    Science.gov (United States)

    Rouhi, M; Sohrabvandi, S; Mortazavian, A M

    2013-01-01

    Probiotics are from functional foods that bring health benefits for humans. Nowadays, a major development in functional foods is related to food containing probiotic cultures, mainly lactic acid bacteria or bifidobacteria. Probiotics must be alive and ingested in sufficient amounts to exert the positive effects on the health and the well-being of the host. Therefore, viability of probiotic products (the minimum viable probiotic cells in each gram or milliliter of product till the time of consumption) is their most important characteristic. However, these organisms often show poor viability in fermented products due to their detrimental conditions. Today, the variety of fermented meat products available around the world is nearly equal to that of cheese. With meat products, raw fermented sausages could constitute an appropriate vehicle for such microorganisms into the human gastrointestinal tract. In present article, the viability of probiotic microorganisms in fermented sausage, the main factors affect their viability, and the sensorial characteristics of final product are discussed.

  5. Role of the nurse consultant in tissue viability.

    Science.gov (United States)

    Harker, J

    Nurse consultant posts were introduced in 2000 with a view to expanding the role of nurses. The author was appointed as a nurse consultant in tissue viability to develop the service already in place in her trust and improve patient care. This article describes the role of the nurse consultant working in tissue viability and identifies the qualities and skills needed to undertake this role.

  6. Water Recovery Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The AES Water Recovery Project (WRP) is advancing environmental control and life support systems water recovery technologies to support human exploration beyond low...

  7. EPA Recovery Mapper

    Data.gov (United States)

    U.S. Environmental Protection Agency — The EPA Recovery Mapper is an Internet interactive mapping application that allows users to discover information about every American Recovery and Reinvestment Act...

  8. Studying bacterial multispecies biofilms

    DEFF Research Database (Denmark)

    Røder, Henriette Lyng; Sørensen, Søren Johannes; Burmølle, Mette

    2016-01-01

    , but the identity and significance of interspecies bacterial interactions is neglected in these analyses. There is therefore an urgent need for bridging the gap between metagenomic analysis and in vitro models suitable for studies of bacterial interactions.Bacterial interactions and coadaptation are important......The high prevalence and significance of multispecies biofilms have now been demonstrated in various bacterial habitats with medical, industrial, and ecological relevance. It is highly evident that several species of bacteria coexist and interact in biofilms, which highlights the need for evaluating...

  9. Preservation of Fusobacterium nucleatum and Peptostreptococcus anaerobius DNA after loss of cell viability.

    Science.gov (United States)

    Brundin, M; Figdor, D; Sundqvist, G; Sjögren, U

    2015-01-01

    To investigate whether DNA from two obligate anaerobes, Fusobacterium nucleatum and Peptostreptococcus anaerobius, is recoverable after loss of cell viability induced by air exposure. Harvested cultures of F. nucleatum and P. anaerobius were killed by exposure to air and stored in phosphate-buffered saline. Dead cells were incubated aerobically for up to 6 months. Every month, the presence of detectable DNA in the cell pellet and supernatant was assessed by conventional and quantitative PCR. Cell staining techniques were used to characterize the cell wall permeability of air-killed cells. Scanning electron microscopy was used to examine viable, freshly killed and stored cells. With conventional PCR, amplifiable DNA was detectable over 6 months in all samples. Quantitative PCR showed a progressive fall in DNA concentration in nonviable cell pellets and a concomitant rise in DNA concentration in the supernatant. DNA staining showed that some air-killed cells retained an intact cell wall. After storage, SEM of both air-killed species revealed shrivelling of the cells, but some cells of P. anaerobius retained their initial form. Amplifiable DNA from F. nucleatum and P. anaerobius was detectable 6 months after loss of viability. Air-killed anaerobes initially retained their cell form, but cells gradually shriveled over time. The morphological changes were more pronounced with the gram-negative F. nucleatum than the gram-positive P. anaerobius. Over 6 months, there was a gradual increase in cell wall permeability with progressive leakage of DNA. Bacterial DNA was recoverable long after loss of cell viability. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  10. Spatially Dispersed Employee Recovery

    DEFF Research Database (Denmark)

    Hvass, Kristian Anders; Torfadóttir, Embla

    2014-01-01

    personnel achieve service recovery. Employee recovery within service research often focuses on front-line employees that work in a fixed location, however a contribution to the field is made by investigating the recovery of spatially dispersed personnel, such as operational personnel in the transport sector...

  11. Recovery from mental illness

    DEFF Research Database (Denmark)

    Petersen, Kirsten Schultz; Friis, Vivi Soegaard; Haxholm, Birthe Lodahl

    2015-01-01

    Mental health services strive to implement a recovery-oriented approach to rehabilitation. Little is known about service users' perception of the recovery approach. The aim is to explore the service user's perspectives on facilitators and barriers associated with recovery. Twelve residents living...

  12. Cell viability of mycorrhiza helper bacteria solid inoculant in different carrier material

    Science.gov (United States)

    Asyiah, Iis Nur; Hindersah, Reginawanti; Harni, Rita

    2018-02-01

    Roots of food crops are colonized by nonpathogenic mycorrhizal fungi which show natural ability to control plant pathogen. Mycorrhizal establishment in plant roots is affected by rhizobacteria, known as mycorrhiza helper bacteria (MHB), which has synergetic effects on mycorrhizal associations. Laboratory experiment has been conducted to assess the best carrier material to develop well-qualified MHB of Pseudomonas diminuta and Bacillus subtilis solid inoculant. Carrier materials were 100 mesh organic matter of agricultural waste. Different spore concentration of both bacterial liquid inoculants were grown on three kinds of 100-mesh organic matter and stored at room temperature up to 90 days. Cell viability of both MHB were counted by serial dilution plate method by using specific medium. The results showed that sugar cane baggase ash was the best carrier material to maintain cell viability for both MHB. However, the population of Pseudomonas diminuta and Bacillus subtilis in sugar cane baggase ash were slightly decreased after 90 days. The use of sugarcane baggase ash for solid MHB inoculant development could be suggested.

  13. Apple, grape or orange juice: Which one offers the best substrate for lactobacilli growth? — A screening study on bacteria viability, superoxide dismutase activity, folates production and hedonic characteristics

    OpenAIRE

    Carlin, Frederic; Renard, Catherine

    2015-01-01

    Fermentation can contribute to improve functional aspects of foods. The first goal of this study was to determine amongst apple, grape and orange juices, the onewith the best bacterial growth performance during fermentation by Lactobacillus strains from commercial and artisanal food origins, at 40 °C for 48 h. The juice with the highest bacterial growth was evaluated for bacteria viability during 4 weeks of cold storage, superoxide dismutase (SOD) activity and folates production a...

  14. [Viability and germination of Hechtia perotensis (Bromeliaceae) seed].

    Science.gov (United States)

    Elizalde, Violeta; García, José Rodolfo; Peña-Valdivia, Cecilia Beatriz; Ybarra, Ma Carmen; Leyva, Otto Raúl; Trejo, Carlos

    2017-03-01

    Endemic populations of Hechtia perotensis have been described in Puebla and Veracruz, Mexico. Good quality seed collections can be used in conservation, research and ecological restoration. To evaluate seed quality of wild and endemic species, some compounds are used as effective promoters of germination, such as potassium nitrate (KNO3) and gibberellic acid (AG3), because they increase seed germination capacity and reduce latency. The triphenyl tetrazolium chloride (tetrazolium) test correlates seed viability because it is based on the activity of dehydrogenases in live tissues that catalyze mitochondrial respiration. The objective of this study was to obtain information on size and weight of capsules and seeds and seed germination and viability of H. perotensis, collected in Veracruz in the year 2012 and 2015. The hypotheses were 1) that seed germination and viability are independent of the year of collection, 2) that there is a tetrazolium concentration that can identify seed viability better than others, and 3) that pretreatment with KNO3 or AG3 improves seed germination. Seed germination was assessed using a completely randomized design with three treatments (control and the germination promoters 0.2 % KNO3 and 500 mg/L AG3), four treatments for the viability test (control, 0.2, 0.5 and 1.0 % of tetrazolium) and six replicates for each treatment. A total of one hundred seeds for germination experiments, and 25 seeds for the viability test were used. The results between and within years were analyzed with ANOVA and multiple comparison with the Tukey test. The proportion of non-germinated seeds was quantified along with the number of normal and abnormal seedlings, seeds with viable embryo, seeds without embryo, and seeds with low or no viability. On average, for the 2012 collected sample, 36 % had viable embryos, 7 % had low viability, 24 % were not viable and 33 % had no embryo. This result was significantly different from the 2015 sample, for which 87 % of

  15. Bacterial proteases, untapped antimicrobial drug targets.

    Science.gov (United States)

    Culp, Elizabeth; Wright, Gerard D

    2017-04-01

    Bacterial proteases are an extensive collection of enzymes that have vital roles in cell viability, stress response and pathogenicity. Although their perturbation clearly offers the potential for antimicrobial drug development, both as traditional antibiotics and anti-virulence drugs, they are not yet the target of any clinically used therapeutics. Here we describe the potential for and recent progress in the development of compounds targeting bacterial proteases with a focus on AAA+ family proteolytic complexes and signal peptidases (SPs). Caseinolytic protease (ClpP) belongs to the AAA+ family of proteases, a group of multimeric barrel-shaped complexes whose activity is tightly regulated by associated AAA+ ATPases. The opportunity for chemical perturbation of these complexes is demonstrated by compounds targeting ClpP for inhibition, activation or perturbation of its associated ATPase. Meanwhile, SPs are also a proven antibiotic target. Responsible for the cleavage of targeting peptides during protein secretion, both type I and type II SPs have been successfully targeted by chemical inhibitors. As the threat of pan-antibiotic resistance continues to grow, these and other bacterial proteases offer an arsenal of novel antibiotic targets ripe for development.

  16. Battleground Energy Recovery Project

    Energy Technology Data Exchange (ETDEWEB)

    Bullock, Daniel [USDOE Gulf Coast Clean Energy Application Center, Woodlands, TX (United States)

    2011-12-31

    In October 2009, the project partners began a 36-month effort to develop an innovative, commercial-scale demonstration project incorporating state-of-the-art waste heat recovery technology at Clean Harbors, Inc., a large hazardous waste incinerator site located in Deer Park, Texas. With financial support provided by the U.S. Department of Energy, the Battleground Energy Recovery Project was launched to advance waste heat recovery solutions into the hazardous waste incineration market, an area that has seen little adoption of heat recovery in the United States. The goal of the project was to accelerate the use of energy-efficient, waste heat recovery technology as an alternative means to produce steam for industrial processes. The project had three main engineering and business objectives: Prove Feasibility of Waste Heat Recovery Technology at a Hazardous Waste Incinerator Complex; Provide Low-cost Steam to a Major Polypropylene Plant Using Waste Heat; and Create a Showcase Waste Heat Recovery Demonstration Project.

  17. Experimental determination of viability loss of Penicillium bilaiae conidia during convective air-drying.

    Science.gov (United States)

    Friesen, Timothy; Hill, Gordon; Pugsley, Todd; Holloway, Greg; Zimmerman, Deanna

    2005-08-01

    A study was conducted on the drying of Penicillium bilaiae, a fungal micro-organism used to promote soil-bound phosphorous uptake in several crop species, such as wheat, canola and pulse crops. A wet pellet formed from a mixture of the inoculant and a starch-based carrier was air-dried to the appropriate water activity to extend the shelf-life of the viable fungal conidia. Convective air-drying was examined as a low-energy alternative to the more expensive freeze-drying technology that is currently in use. Experiments were conducted to measure the loss of conidia viability during drying in a fixed-bed, thin-layer convective dryer. The dryer air inlet temperature and relative humidity were controlled in experiments to determine the effect of thermal and dessicative stresses on conidial viability. The measured survivor fraction was determined to be dependent on solids temperature, moisture content and drying rate. Thermal stresses became significant for process temperatures above 30 degrees C, while the survivor fraction fell sharply below a dry basis moisture ratio of 30%. Slower drying kinetics associated with high inlet air relative humidity were found to significantly improve the recovery of viable conidia. By minimising environmental stresses, survivor fractions of up to 75% could be achieved, but this result fell dramatically with the introduction of more severe conditions. A general linear statistical model is used to quantify experimental error and the significance level of each factor.

  18. Repeatability and reproducibility of Population Viability Analysis (PVA and the implications for threatened species management

    Directory of Open Access Journals (Sweden)

    Clare Morrison

    2016-08-01

    Full Text Available Conservation triage focuses on prioritizing species, populations or habitats based on urgency, biodiversity benefits, recovery potential as well as cost. Population Viability Analysis (PVA is frequently used in population focused conservation prioritizations. The critical nature of many of these management decisions requires that PVA models are repeatable and reproducible to reliably rank species and/or populations quantitatively. This paper assessed the repeatability and reproducibility of a subset of previously published PVA models. We attempted to rerun baseline models from 90 publicly available PVA studies published between 2000-2012 using the two most common PVA modelling software programs, VORTEX and RAMAS-GIS. Forty percent (n = 36 failed, 50% (45 were both repeatable and reproducible, and 10% (9 had missing baseline models. Repeatability was not linked to taxa, IUCN category, PVA program version used, year published or the quality of publication outlet, suggesting that the problem is systemic within the discipline. Complete and systematic presentation of PVA parameters and results are needed to ensure that the scientific input into conservation planning is both robust and reliable, thereby increasing the chances of making decisions that are both beneficial and defensible. The implications for conservation triage may be far reaching if population viability models cannot be reproduced with confidence, thus undermining their intended value.

  19. Evaluating the potential for weed seed dispersal based on waterfowl consumption and seed viability.

    Science.gov (United States)

    Farmer, Jaime A; Webb, Elisabeth B; Pierce, Robert A; Bradley, Kevin W

    2017-12-01

    Migratory waterfowl have often been implicated in the movement of troublesome agronomic and wetland weed species. However, minimal research has been conducted to investigate the dispersal of agronomically important weed species by waterfowl. The two objectives for this project were to determine what weed species are being consumed by ducks and snow geese, and to determine the recovery rate and viability of 13 agronomic weed species after passage through a duck's digestive system. Seed recovered from digestive tracts of 526 ducks and geese harvested during a 2-year field study had 35 020 plants emerge. A greater variety of plant species emerged from ducks each year (47 and 31 species) compared to geese (11 and 3 species). Viable seed from 11 of 13 weed species fed to ducks in a controlled feeding study were recovered. Viability rate and gut retention times indicated potential dispersal up to 2900 km from the source depending on seed characteristics and variability in waterfowl dispersal distances. Study results confirm that waterfowl are consuming seeds from a variety of agronomically important weed species, including Palmer amaranth, which can remain viable after passage through digestive tracts and have potential to be dispersed over long distances by waterfowl. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  20. Ingredient supplementation effects on viability of probiotic bacteria in yogurt.

    Science.gov (United States)

    Dave, R I; Shah, N P

    1998-11-01

    The present investigation studied the effects of cysteine, whey powder, whey protein concentrate, acid casein hydrolysates, or tryptone on the viability of Streptococcus thermophilus, Lactobacillus acidophilus, and bifidobacteria. Changes in pH, titratable acidity, redox potential, and viability of bacteria were monitored during 24 h of fermentation and refrigerated storage (4 degrees C) of yogurt for 35 d. The incubation time that was needed to reach pH 4.5 was considerably affected by the added ingredients. Also, the drop in pH or the increase in acidity and redox potential was dependent on the added ingredients. The addition of cysteine, whey protein concentrate, acid casein hydrolysates, or tryptone improved the viability of bifidobacteria to a variable extent, but whey powder failed to improve their viability. The morphology of S. thermophilus, as shown by electron microscopy, was affected by cysteine at 500 mg/L, possibly as a result of reduced redox potential. Sodium dodecyl sulfate-PAGE and amino acid analyses suggested that the nitrogen source in the form of peptides and amino acids improved the viability of bifidobacteria in yogurt made with a commercial ABT (Lactobacillus acidophilus, bifidobacteria, and Streptococcus thermophilus) starter culture, which showed a dramatic decline in the counts of this organism in previous studies.

  1. A Classification Method for Seed Viability Assessment with Infrared Thermography

    Directory of Open Access Journals (Sweden)

    Sen Men

    2017-04-01

    Full Text Available This paper presents a viability assessment method for Pisum sativum L. seeds based on the infrared thermography technique. In this work, different artificial treatments were conducted to prepare seeds samples with different viability. Thermal images and visible images were recorded every five minutes during the standard five day germination test. After the test, the root length of each sample was measured, which can be used as the viability index of that seed. Each individual seed area in the visible images was segmented with an edge detection method, and the average temperature of the corresponding area in the infrared images was calculated as the representative temperature for this seed at that time. The temperature curve of each seed during germination was plotted. Thirteen characteristic parameters extracted from the temperature curve were analyzed to show the difference of the temperature fluctuations between the seeds samples with different viability. With above parameters, support vector machine (SVM was used to classify the seed samples into three categories: viable, aged and dead according to the root length, the classification accuracy rate was 95%. On this basis, with the temperature data of only the first three hours during the germination, another SVM model was proposed to classify the seed samples, and the accuracy rate was about 91.67%. From these experimental results, it can be seen that infrared thermography can be applied for the prediction of seed viability, based on the SVM algorithm.

  2. Hydrogen Supplementation of Preservation Solution Improves Viability of Osteochondral Grafts

    Directory of Open Access Journals (Sweden)

    Takuya Yamada

    2014-01-01

    Full Text Available Allogenic osteochondral tissue (OCT is used for the treatment of large cartilage defects. Typically, OCTs collected during the disease-screening period are preserved at 4°C; however, the gradual reduction in cell viability during cold preservation adversely affects transplantation outcomes. Therefore, improved storage methods that maintain the cell viability of OCTs are needed to increase the availability of high-quality OCTs and improve treatment outcomes. Here, we evaluated whether long-term hydrogen delivery to preservation solution improved the viability of rat OCTs during cold preservation. Hydrogen-supplemented Dulbecco’s Modified Eagles Medium (DMEM and University of Wisconsin (UW solution both significantly improved the cell viability of OCTs during preservation at 4°C for 21 days compared to nonsupplemented media. However, the long-term cold preservation of OCTs in DMEM containing hydrogen was associated with the most optimal maintenance of chondrocytes with respect to viability and morphology. Our findings demonstrate that OCTs preserved in DMEM supplemented with hydrogen are a promising material for the repair of large cartilage defects in the clinical setting.

  3. [Spontaneous bacterial peritonitis].

    Science.gov (United States)

    Strauss, Edna; Caly, Wanda Regina

    2003-01-01

    Spontaneous bacterial peritonitis occurs in 30% of patients with ascites due to cirrhosis leading to high morbidity and mortality rates. The pathogenesis of spontaneous bacterial peritonitis is related to altered host defenses observed in end-stage liver disease, overgrowth of microorganisms, and bacterial translocation from the intestinal lumen to mesenteric lymph nodes. Clinical manifestations vary from severe to slight or absent, demanding analysis of the ascitic fluid. The diagnosis is confirmed by a number of neutrophils over 250/mm3 associated or not to bacterial growth in culture of an ascites sample. Enterobacteriae prevail and Escherichia coli has been the most frequent bacterium reported. Mortality rates decreased markedly in the last two decades due to early diagnosis and prompt antibiotic treatment. Third generation intravenous cephalosporins are effective in 70% to 95% of the cases. Recurrence of spontaneous bacterial peritonitis is common and can be prevented by the continuous use of oral norfloxacin. The development of bacterial resistance demands the search for new options in the prophylaxis of spontaneous bacterial peritonitis; probiotics are a promising new approach, but deserve further evaluation. Short-term antibiotic prophylaxis is recommended for patients with cirrhosis and ascites shortly after an acute episode of gastrointestinal bleeding.

  4. Recovery and money management.

    Science.gov (United States)

    Rowe, Michael; Serowik, Kristin L; Ablondi, Karen; Wilber, Charles; Rosen, Marc I

    2013-06-01

    Social recovery and external money management are important approaches in contemporary mental health care, but little research has been done on the relationship between the two or on application of recovery principles to money management for people at risk of being assigned a representative payee or conservator. Out of 49 total qualitative interviews, 25 transcripts with persons receiving Social Security insurance or Social Security disability insurance who were at risk of being assigned a money manager were analyzed to assess the presence of recognized recovery themes. The recovery principles of self-direction and responsibility were strong themes in participant comments related to money management. Money management interventions should incorporate peoples' recovery-related motivations to acquire financial management skills as a means to direct and assume responsibility for one's finances. Staff involved in money management should receive training to support client's recovery-related goals. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

  5. Interfering with bacterial gossip

    DEFF Research Database (Denmark)

    Bjarnsholt, Thomas; Tolker-Nielsen, Tim; Givskov, Michael

    2011-01-01

    defense. Antibiotics exhibit a rather limited effect on biofilms. Furthermore, antibiotics have an ‘inherent obsolescence’ because they select for development of resistance. Bacterial infections with origin in bacterial biofilms have become a serious threat in developed countries. Pseudomonas aeruginosa...... that appropriately target bacteria in their relevant habitat with the aim of mitigating their destructive impact on patients. In this review we describe molecular mechanisms involved in “bacterial gossip” (more scientifically referred to as quorum sensing (QS) and c-di-GMP signaling), virulence, biofilm formation......, resistance and QS inhibition as future antimicrobial targets, in particular those that would work to minimize selection pressures for the development of resistant bacteria....

  6. Population-specific life histories contribute to metapopulation viability

    Science.gov (United States)

    Halsey, Samniqueka J.; Bell, Timothy J.; McEachern, A. Kathryn; Pavlovic, Noel B.

    2016-01-01

    Restoration efforts can be improved by understanding how variations in life-history traits occur within populations of the same species living in different environments. This can be done by first understanding the demographic responses of natural occurring populations. Population viability analysis continues to be useful to species management and conservation with sensitivity analysis aiding in the understanding of population dynamics. In this study, using life-table response experiments and elasticity analyses, we investigated how population-specific life-history demographic responses contributed to the metapopulation viability of the Federally threatened Pitcher's thistle (Cirsium pitcheri). Specifically, we tested the following hypotheses: (1) Subpopulations occupying different environments within a metapopulation have independent demographic responses and (2) advancing succession results in a shift from a demographic response focused on growth and fecundity to one dominated by stasis. Our results showed that reintroductions had a positive contribution to the metapopulation growth rate as compared to native populations which had a negative contribution. We found no difference in succession on the contribution to metapopulation viability. In addition, we identified distinct population-specific contributions to metapopulation viability and were able to associate specific life-history demographic responses. For example, the positive impact of Miller High Dunes population on the metapopulation growth rate resulted from high growth contributions, whereas increased time of plant in stasis for the State Park Big Blowout population resulted in negative contributions. A greater understanding of how separate populations respond in their corresponding environment may ultimately lead to more effective management strategies aimed at reducing extinction risk. We propose the continued use of sensitivity analyses to evaluate population-specific demographic influences on

  7. Viability of bifidobacteria in commercial dairy products during refrigerated storage.

    Science.gov (United States)

    Shin, H S; Lee, J H; Pestka, J J; Ustunol, Z

    2000-03-01

    Commercial milk and two brands of yogurt containing bifidobacteria were obtained from retail outlets. All products were evaluated for viability of bifidobacteria and lactic acid bacteria during refrigerated storage at 4 degrees C. Milk was evaluated at 9, 6, and 3 days prior and past its expiration date. The yogurts were evaluated at 3, 2, and 1 week prior and past their expiration. Viability of bifidobacteria and lactic acid bacteria in milk and yogurt remained above 10(6) CFU/ml or g until the expiration date of the respective products. This microbial concentration is the recommended minimum dose to receive the health benefits of these organisms.

  8. Economic Viability of Brewery Spent Grain as a Biofuel

    Energy Technology Data Exchange (ETDEWEB)

    Morrow, Charles [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-01-01

    This report summarizes an investigation into the technical feasibility and economic viability of use grain wastes from the beer brewing process as fuel to generate the heat needed in subsequent brewing process. The study finds that while use of spent grain as a biofuel is technically feasible, the economics are not attractive. Economic viability is limited by the underuse of capital equipment. The investment in heating equipment requires a higher utilization that the client brewer currently anticipates. It may be possible in the future that changing factors may swing the decision to a more positive one.

  9. Radiopeptide internalisation and externalization assays: cell viability and radioligand integrity.

    Science.gov (United States)

    Naqvi, Syed Ali Raza; Sosabowski, Jane K; Nagra, Saeed Ahamad; Ishfaq, Malik M; Mather, Stephen J; Matzow, Torkjel

    2011-01-01

    Various aspects of radiopeptide receptor-mediated cell internalisation and externalization assays were assessed, including the integrity of externalized peptides and the effect of varying the pH and incubation time of the acid wash step (to remove surface receptor-bound ligand) on efficacy and cell viability. The observed intact proportion of externalized peptide was 5-10%, and acid wash buffers with pH 2.8 or below were found to be detrimental to cell viability and integrity, particularly following prolonged incubation times. Copyright © 2010 Elsevier Ltd. All rights reserved.

  10. Radiopeptide internalisation and externalisation assays: Cell viability and radioligand integrity

    International Nuclear Information System (INIS)

    Raza Naqvi, Syed Ali; Sosabowski, Jane K.; Ahamad Nagra, Saeed; Ishfaq, Malik M.; Mather, Stephen J.; Matzow, Torkjel

    2011-01-01

    Various aspects of radiopeptide receptor-mediated cell internalisation and externalisation assays were assessed, including the integrity of externalised peptides and the effect of varying the pH and incubation time of the acid wash step (to remove surface receptor-bound ligand) on efficacy and cell viability. The observed intact proportion of externalised peptide was 5-10%, and acid wash buffers with pH 2.8 or below were found to be detrimental to cell viability and integrity, particularly following prolonged incubation times.

  11. Bacterial leaching of pyritic gold ores

    Energy Technology Data Exchange (ETDEWEB)

    Gagliardi, F.M.; Cashion, J.D.; Brown, L.J. [Monash Univ., Clayton, VIC (Australia). Dept. of Physics; Jay, W.H. [Monash Univ., Clayton, VIC (Australia). Chemical Engineering Department

    1996-12-31

    The bacterial oxidation process is well known in nature but has only recently come under investigation as a viable and relatively clean method of gold recovery from ores. However there is currently little information about the process at an atomic scale. It is known that the bacterial attack progresses preferentially along grain boundaries which is precisely where the gold has been deposited from aqueous infiltration. Samples have been obtained from the Wiluna mine in Western Australia consisting of the original ore, 2 pre-treatments, and from six successive bacterial reactors. {sup 57}Fe Moessbauer spectra taken at room temperature show only two quadrupole split doublets which can be ascribed to pyrite, FeS{sub 2}, and arsenopyrite, FeAsS. However, the presence of any superparamagnetic oxide or oxyhydroxide species would be expected to give a spectrum very similar to that of pyrite and would be undetectable in small quantities. At a temperature of 5K, a broad magnetically split sextet is observable with a mean hyperfine field of approximately 50T. This field is characteristic of magnetically ordered ferric iron surrounded by an octahedron of oxygens. The intensity and characteristics of this subspectrum alters through the series and interpretations will be given on the oxidation products of the bacterial leaching

  12. Bacterial leaching of pyritic gold ores

    International Nuclear Information System (INIS)

    Gagliardi, F.M.; Cashion, J.D.; Brown, J.; Jay, W.H.

    1998-01-01

    Full text: Pyritic ores (pyrite and arsenopyrite) containing gold concentrations in excess of 50g Au/t can be processed to recover the gold by the removal of the sulphur from the ore. This may be achieved by roasting (producing sulphur dioxide emissions), pressure oxidation (expensive and suitable for large high grade deposits), pressure leaching (still currently being developed) or bacterial oxidation. The bacterial oxidation process is a well known process in nature but has only recently come under investigation as a economically viable and relatively clean method of gold recovery from deep low grade sulphidic ores. Samples were obtained from the Wiluna Gold Mine in Western Australia consisting of the original ore, six successive bacterial reactors and the final products. Moessbauer experiments have been performed at room temperature, liquid nitrogen and liquid helium temperatures, and in applied magnetic fields. The main components of the iron phases which were present during the bacterial treatment were pyrite and arsenopyrite which were readily oxidised by the bacteria. Ferric sulfates and ferric arsenates were identified as by-products of the process with a small amount of the oxyhydroxide goethite. These results are in contrast to the similar study of the Fairview Mine in South Africa where principally Fe(II) species were observed

  13. Bacterial leaching of pyritic gold ores

    International Nuclear Information System (INIS)

    Gagliardi, F.M.; Cashion, J.D.; Brown, L.J.; Jay, W.H.

    1996-01-01

    The bacterial oxidation process is well known in nature but has only recently come under investigation as a viable and relatively clean method of gold recovery from ores. However there is currently little information about the process at an atomic scale. It is known that the bacterial attack progresses preferentially along grain boundaries which is precisely where the gold has been deposited from aqueous infiltration. Samples have been obtained from the Wiluna mine in Western Australia consisting of the original ore, 2 pre-treatments, and from six successive bacterial reactors. 57 Fe Moessbauer spectra taken at room temperature show only two quadrupole split doublets which can be ascribed to pyrite, FeS 2 , and arsenopyrite, FeAsS. However, the presence of any superparamagnetic oxide or oxyhydroxide species would be expected to give a spectrum very similar to that of pyrite and would be undetectable in small quantities. At a temperature of 5K, a broad magnetically split sextet is observable with a mean hyperfine field of approximately 50T. This field is characteristic of magnetically ordered ferric iron surrounded by an octahedron of oxygens. The intensity and characteristics of this subspectrum alters through the series and interpretations will be given on the oxidation products of the bacterial leaching

  14. Efficacy of an anaerobic swab transport system to maintain aerobic and anaerobic microorganism viability after storage at -80 degrees C.

    Science.gov (United States)

    Musser, Jeffrey M B; Gonzalez, Rosa

    2011-01-01

    An Amies agar gel swab transport system was evaluated for its ability to maintain bacterial viability and relative quantity after freezing at -80°C. Nine American Type Culture Collection (ATCC) bacterial strains were used: 3 anaerobic strains (Propionibacterium acnes, Peptostreptococcus anaerobius, and Clostridium sporogenes) and 6 facultative or strict aerobic bacterial strains (Stenotrophomonas maltophilia, Escherichia coli ([ATCC 25922 and ATCC 11775], Salmonella enterica subsp. enterica serovar Typhimurium, Staphylococcus saprophyticus, and Lactobacillus casei). The bacterial species were chosen because they corresponded to bacteria identified in psittacine feces and cloacal samples. There were no significant differences between growth scores at baseline and after storage at -80°C for 40 days for any of the bacteria examined after 48 and 72 hr of incubation, with the exception of P. anaerobius. For P. anaerobius, there was a significant reduction (P < 0.001) in the growth score after storage at -80°C for 40 days from that of the baseline; however, the bacteria were still viable. The tested swab transport system may be useful when lengthy storage and transport times necessitate freezing samples prior to culture.

  15. The viability of Lactobacillus fermentum CECT5716 is not essential to exert intestinal anti-inflammatory properties.

    Science.gov (United States)

    Rodríguez-Nogales, Alba; Algieri, Francesca; Vezza, Teresa; Garrido-Mesa, Natividad; Olivares, Mónica; Comalada, Mònica; Riccardi, Carlo; Utrilla, Ma Pilar; Rodríguez-Cabezas, Ma Elena; Galvez, Julio

    2015-04-01

    Probiotics have been used as alternative therapies in intestinal inflammatory disorders. Many studies have shown that different bacterial probiotic strains possess immuno-modulatory and anti-inflammatory properties. However, there is an increasing interest in the use of non-viable bacteria to reduce the risk of microbial translocation and infection. The aim of this study was to evaluate whether the viability of L. fermentum CECT5716 is essential to exert its intestinal anti-inflammatory effect. We compared the preventative effects of viable and non-viable probiotic in the TNBS model of rat colitis. In vitro studies were also performed in Caco-2 and RAW 264.7 cells to evaluate the probiotic effects on IL-8, IL-1β and nitrite production, and p44/42 and p38 MAP kinase protein expressions. In vitro results revealed a decrease in the stimulated production of pro-inflammatory mediators regardless of the viability of the probiotic. Likewise, both forms of the probiotic administered to colitic rats produced a significant reduction of IL-1β and TNF-α levels and colonic iNOS expression. In conclusion, both live and dead L. fermentum CECT5716 have been demonstrated to attenuate the inflammatory process and diminish the production of some of the inflammatory mediators. In fact, the viability of this probiotic did not affect its immuno-modulatory and anti-inflammatory properties.

  16. Classic Peripheral Signs of Subacute Bacterial Endocarditis

    Directory of Open Access Journals (Sweden)

    Yooyoung Chong

    2016-10-01

    Full Text Available A 50-year-old female patient with visual disturbances was referred for further evaluation of a heart murmur. Fundoscopy revealed a Roth spot in both eyes. A physical examination showed peripheral signs of infective endocarditis, including Osler nodes, Janeway lesions, and splinter hemorrhages. Our preoperative diagnosis was subacute bacterial endocarditis with severe aortic regurgitation. The patient underwent aortic valve replacement and was treated with intravenous antibiotics for 6 weeks postoperatively. The patient made a remarkable recovery and was discharged without complications. We report this case of subacute endocarditis with all 4 classic peripheral signs in a patient who presented with visual disturbance.

  17. Bacterial surface adaptation

    Science.gov (United States)

    Utada, Andrew

    2014-03-01

    Biofilms are structured multi-cellular communities that are fundamental to the biology and ecology of bacteria. Parasitic bacterial biofilms can cause lethal infections and biofouling, but commensal bacterial biofilms, such as those found in the gut, can break down otherwise indigestible plant polysaccharides and allow us to enjoy vegetables. The first step in biofilm formation, adaptation to life on a surface, requires a working knowledge of low Reynolds number fluid physics, and the coordination of biochemical signaling, polysaccharide production, and molecular motility motors. These crucial early stages of biofilm formation are at present poorly understood. By adapting methods from soft matter physics, we dissect bacterial social behavior at the single cell level for several prototypical bacterial species, including Pseudomonas aeruginosa and Vibrio cholerae.

  18. Bacterial Meningitis in Infants

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2004-04-01

    Full Text Available A retrospective study of 80 infantile patients (ages 30-365 days; 47 male, 33 female with culture-proven bacterial meningitis seen over a 16 year period (1986-2001 is reported from Taiwan.

  19. Factitious Bacterial Meningitis Revisited

    Science.gov (United States)

    Peterson, E.; Thrupp, L.; Uchiyama, N.; Hawkins, B.; Wolvin, B.; Greene, G.

    1982-01-01

    Nonviable gram-negative bacilli were seen in smears of cerebrospinal fluid from eight infants in whom bacterial meningitis was ruled out. Tubes from commercial kits were the source of the factitious organisms. PMID:7153328

  20. Vimentin in Bacterial Infections

    DEFF Research Database (Denmark)

    Mak, Tim N; Brüggemann, Holger

    2016-01-01

    filaments (IFs). IFs have not only roles in maintaining the structural integrity of the cell, but they are also involved in many cellular processes including cell adhesion, immune signaling, and autophagy, processes that are important in the context of bacterial infections. Here, we summarize the knowledge...... about the role of IFs in bacterial infections, focusing on the type III IF protein vimentin. Recent studies have revealed the involvement of vimentin in host cell defenses, acting as ligand for several pattern recognition receptors of the innate immune system. Two main aspects of bacteria......-vimentin interactions are presented in this review: the role of vimentin in pathogen-binding on the cell surface and subsequent bacterial invasion and the interaction of cytosolic vimentin and intracellular pathogens with regards to innate immune signaling. Mechanistic insight is presented involving distinct bacterial...

  1. Post-cryopreservation viability of the benthic freshwater diatom Planothidium frequentissimum depends on light levels.

    Science.gov (United States)

    Buhmann, Matthias T; Day, John G; Kroth, Peter G

    2013-08-01

    Over recent years, several planktonic and benthic freshwater diatom taxa have been established as laboratory model strains. In common with most freshwater diatoms the pennate diatom Planothidium frequentissimum suffers irreversible cell shrinkage on prolonged maintenance by serial transfers, without induction of the sexual cycle. Therefore, alternative strategies are required for the long-term maintenance of this strain. Conventional colligative cryopreservation approaches have previously proven unsuccessful with no regrowth. However, in this study using 5% dimethyl sulfoxide (Me2SO), controlled cooling at 1 °C min(-1), automated ice seeding and cooling to -40 °C with a final plunge into liquid nitrogen, viability levels were enhanced from 0.3 ± 0.4% to 80 ± 3%, by incorporating a 48 h dark-recovery phase after rewarming. Omission, or reduction, of this recovery step resulted in obvious cell damage with photo-bleaching of pigments, indicative of oxidative-stress induced cell damage, with subsequent deterioration of cellular architecture. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Anaerobic bacterial meningitis in adults.

    Science.gov (United States)

    Lee, Jun-Jun; Lien, Chia-Yi; Chien, Chun-Chih; Huang, Chi-Ren; Tsai, Nai-Wen; Chang, Chiung-Chih; Lu, Cheng-Hsien; Chang, Wen-Neng

    2018-01-22

    Anaerobic infection is a very uncommon condition in adult bacterial meningitis (ABM), and its clinical characteristics have yet to be clarified. We enrolled 540 patients with culture-proven bacterial meningitis during a study period of 30 years (1986-2015), of whom 13 (2.4%) had anaerobic infections. These 13 patients were eight men and five women, aged 22-77 years. Among them, 53.8% (7/13) had a postneurosurgical state as the preceding event, and 79.6% (10/13) had underlying medical conditions including diabetes mellitus, malignancy, liver cirrhosis, cerebral infarct and alcoholism. Nosocomial and mixed infections were found in 15.5% (2/13) and 46.1% (6/13) of the patients, respectively. A total of 14 anaerobic strains were isolated from cerebrospinal fluid specimens, including nine Gram-negative (G(-)) strains: Fusobacterium nucleatum (3), Prevotella species (3) and Bacteroides fragilis (3), and five Gram-positive (G(+)) strains: Propionibacterium acnes (3) and Peptostreptococcus micros (also known as Parvimonas micra) (2). All of the implicated G(+) anaerobic bacteria were susceptible to penicillin, and no multiple drug-resistant strains were found among the implicated G(-) anaerobic bacteria. Despite treatment, 30.8% (4/13) of the patients died. Of the nine survivors, 22.2% (2/9) had a full recovery, while the other 77.8% (7/9) had varying degrees of neurological deficits. Compared with the good outcome group (n = 6, modified Rankin scale (mRS) scores: 0-2), the poor outcome group (n = 7, mRS scores ≧3) had higher incidence of seizure. These results may offer a preliminary view of the clinical characteristics of anaerobic ABM. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. [Diagnosis of bacterial vaginosis].

    Science.gov (United States)

    Djukić, Slobodanka; Ćirković, Ivana; Arsić, Biljana; Garalejić, Eliana

    2013-01-01

    Bacterial vaginosis is a common, complex clinical syndrome characterized by alterations in the normal vaginal flora. When symptomatic, it is associated with a malodorous vaginal discharge and on occasion vaginal burning or itching. Under normal conditions, lactobacilli constitute 95% of the bacteria in the vagina. Bacterial vaginosis is associated with severe reduction or absence of the normal H2O2-producing lactobacilli and overgrowth of anaerobic bacteria and Gardnerella vaginalis, Atopobium vaginae, Mycoplasma hominis and Mobiluncus species. Most types of infectious disease are diagnosed by culture, by isolating an antigen or RNA/DNA from the microbe, or by serodiagnosis to determine the presence of antibodies to the microbe. Therefore, demonstration of the presence of an infectious agent is often a necessary criterion for the diagnosis of the disease. This is not the case for bacterial vaginosis, since the ultimate cause of the disease is not yet known. There are a variety of methods for the diagnosis of bacterial vaginosis but no method can at present be regarded as the best. Diagnosing bacterial vaginosis has long been based on the clinical criteria of Amsel, whereby three of four defined criteria must be satisfied. Nugent's scoring system has been further developed and includes validation of the categories of observable bacteria structures. Up-to-date molecular tests are introduced, and better understanding of vaginal microbiome, a clear definition for bacterial vaginosis, and short-term and long-term fluctuations in vaginal microflora will help to better define molecular tests within the broader clinical context.

  4. Port viability for choice making among shipping companies in West ...

    African Journals Online (AJOL)

    In this paper, the study of port viability for choice making among shipping companies in West Africa sub-region trade route was conducted. Discriminant analysis was used to ascertain the consistency of the attributes of ports that establish their overall attractiveness to the carriers. The critical valued port attributes deduced ...

  5. J_'-9_7__ Degloving injuries and flap viability assesstnent

    African Journals Online (AJOL)

    necessitated euthanasia and reassessment of the trial protocol. Flap viability assessment in both groups was made clinically, histologically and by planirnerry. RG.3. Flap raised and partially de-epithelialised using wire bristle dermabrader. series.IO Approximately 50% of the avulsed flap was dis- carded and a maximum of ...

  6. Studies On Fermentation, Alcohol Production And Viability In ...

    African Journals Online (AJOL)

    Eighteen mutant yeasts (SCM 01 – SCM 18) selected (after visual examination) were tested for fermentation, alcohol production and viability by acid and gas production, reduction in specific gravity and turbidity respectively, with sugars and delignified sugarcane bagasse. The yeasts had varied fermentation profiles in ...

  7. Low-level waste vitrification contact maintenance viability study

    Energy Technology Data Exchange (ETDEWEB)

    Leach, C.E., Westinghouse Hanford

    1996-07-12

    This study investigates the economic viability of contact maintenance in the Low-Level Waste Vitrification Facility, which is part of the Hanford Site Tank Waste Remediation System. This document was prepared by Flour Daniel, Inc., and transmitted to Westinghouse Hanford Company in September 1995.

  8. Potential carbon credit and community expectations towards viability ...

    African Journals Online (AJOL)

    The paper presents results of the potential carbon credit and community expectations towards viability of REDD+ projects in Ugalla- Masito ecosystem using a case of Ilagala and Karago villages whereby REDD+ is being piloted. Various data collection methods were employed and these included focused group discussion, ...

  9. Banana nectar as a medium for testing pollen viability and ...

    African Journals Online (AJOL)

    A quick and reliable method for evaluating pollen quality is essential in a breeding program, especially in a crop such as banana that is characterized by high male and female sterility. In this study the germination and viability of banana pollen was evaluated in a sucrose solution and diluted banana nectar. Twenty banana ...

  10. Proof of Economic Viability of Blended Learning Business Models

    Science.gov (United States)

    Druhmann, Carsten; Hohenberg, Gregor

    2014-01-01

    The discussion on economically sustainable business models with respect to information technology is lacking in many aspects of proven approaches. In the following contribution the economic viability is valued based on a procedural model for design and evaluation of e-learning business models in the form of a case study. As a case study object a…

  11. The effects of storage conditions on the viability of ...

    African Journals Online (AJOL)

    Long-terms recoverability of enteropathogens is necessary for future epidemiological studies to screen stool samples when conditions do not permit immediate processing. The aim of this study was to determine the viability and the recoverability of three enteropathogens bacteria (Yersinia enterocolitica, Vibrio cholerae O: 1 ...

  12. The Economy and Democracy: Viability and Challenges for ...

    African Journals Online (AJOL)

    This paper, critically, examines the viability for developing sustainable democracy in Nigeria against the background of the country's enormous economic potentials and the economic reforms introduced following the return of democracy in 1999. On this context, the paper argues that the greatest challenge for developing a ...

  13. Effect of Pretreatments on Seed Viability During Fruit Development ...

    African Journals Online (AJOL)

    Fiifi Baidoo

    foil and incubated for 4 h after which the embryos were then washed and observed for red colouration. The coloured embryos were counted as viable. Percentage viability from five replicates were recorded (Demir & Ellis, 1992). Seed pretreatments and germination tests. Five seeds from each seed lots of the two harvests ...

  14. The practice of investment viability appraisal in Akure, Nigeria ...

    African Journals Online (AJOL)

    This paper examines the role played by valuers in choosing the right viability appraisal technique for an investment appraisal. Structured questionnaire was administered on Twenty one (21) registered and practicing Estate Surveying and Valuation firms in Akure out of which fourteen (14) were retrieved and found good for ...

  15. Effect of pretreatments on seed viability during fruit development of ...

    African Journals Online (AJOL)

    Studies to identify the stage at which developing fruits of Irvingia gabonensis (var. excelsa and var. gabonensis), picked from standing trees and/or forest floors, attain maximum viability and germinability were conducted in two harvesting seasons in 2000 and 2001. Some pretreatment methods were used as a means of ...

  16. Economic viability of new launched school lunch programmes

    DEFF Research Database (Denmark)

    Jensen, Jørgen Dejgård; Smed, Sinne; Mørkbak, Morten Raun

    2013-01-01

    activities related to the schools’ support and the users’ feeling of ownership, as well as internal professionalism and leadership in the implementation of the school lunch programme are important for the viability of the programme. Strong performance on the latter factors might to some extent compensate...

  17. Assessment of viability of microorganisms employing fluorescence techniques

    NARCIS (Netherlands)

    Breeuwer, P.

    1996-01-01


    Viability assessment of microorganisms is relevant for a wide variety of applications in industry, including evaluation of inactivation treatments and quality assessment of starter cultures for beer, wine, and yoghurt production.

    Usually, the ability of microbial cells to

  18. The economic and social viability of Tanzanian Wildlife Management Areas

    DEFF Research Database (Denmark)

    Homewood, Katherine; Bluwstein, Jevgeniy; Lund, Jens Friis

    This policy brief contributes to assessing the economic and social viability of Tanzania’s Wildlife Management Areas (WMAs) through preliminary findings by the ‘Poverty and ecosystem Impacts of Tanzania’s Wildlife Management Areas’ (PIMA) project, focusing on benefits, costs, and their distribution...

  19. Sewage sludge pasteurization by gamma radiation: Financial viability case studies

    Science.gov (United States)

    Swinwood, Jean F.; Kotler, Jiri

    This paper examines the financial viability of sewage sludge pasteurization by gamma radiation, by examining the following three North American scenarios: 1) Small volume sewage treatment plant experiencing high sludge disposal costs. 2) Large volume sewage treatment plant experiencing low sludge disposal costs. 3) Large volume sewage treatment plant experiencing high sludge disposal costs.

  20. Optimizing cell viability in droplet-based cell deposition

    NARCIS (Netherlands)

    Hendriks, Jan; Visser, C.W.; Henke, S.J.; Leijten, Jeroen Christianus Hermanus; Saris, Daniël B.F.; Sun, Chao; Lohse, Detlef; Karperien, Hermanus Bernardus Johannes

    2015-01-01

    Biofabrication commonly involves the use of liquid droplets to transport cells to the printed structure. However, the viability of the cells after impact is poorly controlled and understood, hampering applications including cell spraying, inkjet bioprinting, and laser-assisted cell transfer. Here,

  1. Financial viability of district mutual health insurance schemes of ...

    African Journals Online (AJOL)

    Since its implementation, unsubstantiated reports indicate increasing health care and administra-tive costs of the various DMHIS across the country without any corresponding increase in the premium level. We sought to assess the financial viability of the DMHIS in Lawra (LDMHIS) and Sissala East (SEDMHIS) districts, ...

  2. Pollen diversity, viability and floral structure of some Musa genotypes

    African Journals Online (AJOL)

    This experiment was designed to study the floral structure, pollen morphology and the potential pollen viability of five Musa genotypes obtained from the Musa field germplasm bank at the Faculty of Agriculture & Natural Resources Management farm, Ebonyi State University, Abakaliki. Palynological investigation was carried ...

  3. Determination of pollen viability, germination ratios and morphology ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-12-03

    Dec 3, 2008 ... regions (Asma, 2000). Flowering and fertilization are critical for fruit set in stone fruits. There are several barriers for fertilization. Poor or malfunctioning pollen production is among these barriers in apricot genotypes. It is known that internal and external factors limit pollen production, viability and germination ...

  4. PET/SPECT imaging : From carotid vulnerability to brain viability

    NARCIS (Netherlands)

    Meerwaldt, Robbert; Slart, Riemer H. J. A.; van Dam, Gooitzen M.; Luijckx, Gert-Jan; Tio, Rene A.; Zeebregts, Clark J.

    Background: Current key issues in ischemic stroke are related to carotid plaque vulnerability, brain viability, and timing of intervention. The treatment of ischemic stroke has evolved into urgent active interventions, as 'time is brain'. Functional imaging such as positron emission tomography

  5. The viability of business data mining in the sports environment ...

    African Journals Online (AJOL)

    Data mining can be viewed as the process of extracting previously unknown information from large databases and utilising this information to make crucial business decisions (Simoudis, 1996: 26). This paper considers the viability of using data mining tools and techniques in sports, particularly with regard to mining the ...

  6. Degloving injuries and flap viability assessment | Widgerow | South ...

    African Journals Online (AJOL)

    Degloving injuries are associated with major morbidity. The management of these injuries is still not resolved. The method of management used by the authors involves the harvesting of split skin from the surface of the flap and assessment of flap viability based on surface dennal capillary bleeding. The skin grafts are then ...

  7. Viability of bull semen extended with commercial semen extender ...

    African Journals Online (AJOL)

    After macroscopic evaluation, semen was pooled and aliquoted randomly into Triladyl, modified Ham's F10, and TCM-199 culture media, and then stored at 24 °C. Sperm motility parameters, morphology, and viability were analysed with computer aided sperm analysis (CASA) after 0, 24, 48 and 72 hours. The study was ...

  8. Seed viability, germination and seedling growth of canola ( Brassica ...

    African Journals Online (AJOL)

    Mutation induction is considered as an effective way to enrich plant genetic variation, particularly for traits with a very low level of genetic variation. The objectives of this study were to evaluate the effect of different dosages of chemical mutagens on seed germination, seed viability and seedling growth characteristics and to ...

  9. Interactions between Plant Extracts and Cell Viability Indicators ...

    African Journals Online (AJOL)

    Interactions between Plant Extracts and Cell Viability. Indicators during Cytotoxicity Testing: Implications for. Ethnopharmacological Studies. Sze Mun Chan1, Kong Soo Khoo2 and Nam Weng Sit1*. 1Department of Biomedical Science, 2Department of Chemical Science, Faculty of Science, Universiti Tunku Abdul Rahman,.

  10. Morphology and viability of castor bean genotypes pollen grains

    Directory of Open Access Journals (Sweden)

    Maria Selma Alves Silva Diamantino

    2016-01-01

    Full Text Available The objective of this work was to characterize the morphology and viability of the pollen of 15 genotypes of castor bean (Ricinus communis L. and to generate information that can assist in the selection of highly promising male parents for future use in genetic improvement programs aimed at producing seeds for oil extraction. Acetolysis and scanning electron microscopy was used to characterize the morphology of the pollen. The viability of the pollen grains was estimated by in vitro germination and colorimetric analysis (acetocarmine 2% and 2, 3, 5-triphenyltetrazolium chloride 1%. For the in vitro germination, pollen grains were grown in 10 types of solidified culture medium consisting of different concentrations of sucrose, boric acid, calcium nitrate, magnesium sulfate and potassium nitrate. The pollen grains had the following characteristics: medium size, isopolar and subspheroidal shape, radial symmetry, circular ambit, 3-colporate, elongated endoapertures, tectate exine and granulated sexine. The acetocarmine dye overestimated pollen viability. The media M5 and M8 were the most efficient at promoting the germination of pollen grains. The studied genotypes had high levels of viability and can therefore be used as male parents in genetic improvement programs.

  11. PBMC and MDAMB-231 cellular viability after telecobalt irradiation

    International Nuclear Information System (INIS)

    Andrade, Lidia M.; Campos, Tarcisio P.R.

    2002-01-01

    Radiotherapy by gamma rays are used for cancer treatment. Ionizing radiation effects on cells has been investigated. Studies in vitro were developed using tumor cell lines and ionizing radiation. The aim of this research was to test the cellular viability response of two cell types through MTT assay: human peripheral blood mononuclear cell (PBMC) and human breast carcinoma cell line MDAMB-231. These cells were irradiated with 60 Co source Theratron 80 radiotherapy machine from Atomic Energy Canada Limited with 20 x 20 cm field at 136.4 cGy/min, surface source distance 70 cm. Culture flasks contained 10 4 , 10 5 and 10 6 cells were irradiated with 100 Gy, 25 Gy, and 50 Gy using non fractionated doses. Cellular viability were evaluated 1h, 24h, 48h and 72h after irradiation and samples were measured by optical density at 595nm. Our results show that PBMC cells present lower cellular viability post irradiation. On the other hand, MDAMB-231 cells maintain viability after 50 Gy irradiation at 72h indicating cellular radioresistance. (author)

  12. Effect of salt hyperosmotic stress on yeast cell viability

    Directory of Open Access Journals (Sweden)

    Logothetis Stelios

    2007-01-01

    Full Text Available During fermentation for ethanol production, yeasts are subjected to different kinds of physico-chemical stresses such as: initially high sugar concentration and low temperature; and later, increased ethanol concentrations. Such conditions trigger a series of biological responses in an effort to maintain cell cycle progress and yeast cell viability. Regarding osmostress, many studies have been focused on transcriptional activation and gene expression in laboratory strains of Saccharomyces cerevisiae. The overall aim of this present work was to further our understanding of wine yeast performance during fermentations under osmotic stress conditions. Specifically, the research work focused on the evaluation of NaCl-induced stress responses of an industrial wine yeast strain S. cerevisiae (VIN 13, particularly with regard to yeast cell growth and viability. The hypothesis was that osmostress conditions energized specific genes to enable yeast cells to survive under stressful conditions. Experiments were designed by pretreating cells with different sodium chloride concentrations (NaCl: 4%, 6% and 10% w/v growing in defined media containing D-glucose and evaluating the impact of this on yeast growth and viability. Subsequent fermentation cycles took place with increasing concentrations of D-glucose (20%, 30%, 40% w/v using salt-adapted cells as inocula. We present evidence that osmostress induced by mild salt pre-treatments resulted in beneficial influences on both cell viability and fermentation performance of an industrial wine yeast strain.

  13. Measuring the effect of field viability on wheat yield

    DEFF Research Database (Denmark)

    Olsen, Jakob Vesterlund; Schou, Jesper Sølver

    showing a significant effect on yields. Further research may involve estimating the effect of field characteristics on the aggregated economic farm performance. The field viability index has multiple applications in e.g. benchmarking, leasing or buying arrangements, and for identifying potential land...

  14. Dormancy, activation and viability of Rhizopus oligosporus sporangiospores

    NARCIS (Netherlands)

    Thanh, N.V.; Nout, M.J.R.

    2004-01-01

    Interruption of dormancy to improve viability of Rhizopus oligosporus sporangiospores is crucial for the application of stored starter cultures for fungal (tempe) production. We aimed to assess the extent of dormancy and factors that could result in activation. Whereas heat treatments were

  15. Influence of gamma irradiation on pollen viability, germination ability ...

    African Journals Online (AJOL)

    July 9th, 11th, 15th, 21st and 28th) and pollen age (0th and 1st days) on the pollen viability, germination ability and fruit and seed-set were investigated in pumpkin (Cucurbita moschata Duchesne ex Poir.) and winter squash (Cucurbita maxima ...

  16. Research Note on viability of herbicide and Hormone - treated ...

    African Journals Online (AJOL)

    The responses and viability of acid scarified seeds of four tropical weeds to gibberellic acid and seven herbicides including Galex, Gramoxone, 2 - 4 D, Atrazine, Simazine, Roundup and Primextra in the Laboratory were investigated. The weeds used are Cassia occidentalis, Cassia obtusifolia Cassia hirtusa and ...

  17. Effect of Storage Materials on Viability and Proximate Composition ...

    African Journals Online (AJOL)

    ADOWIE PERE

    /ja. Effect of Storage Materials on Viability and Proximate Composition of Garcinia kola. Heckel. *1OLAYINKA ... amount of crude fat (4.18%), crude fibre (2.88%) and crude protein (2.09%) as well as negligible amount of ash content. (0.78%).

  18. Comparative Efficacy and Economic Viability of Trichoderma Strains ...

    African Journals Online (AJOL)

    FIRST LADY

    used fungicides in the control of Phytophthora pod -rot of cocoa in Nigeria as well as their economic viability due to their ability to improve cocoa production. African Research Review Vol. 4(3a) July ... two-step liquid/solid state fermentation according to Hebbar et al (2000) using cassava flakes as the solid matrix. Incubation ...

  19. Sewage sludge pasteurization by gamma radiation: financial viability case studies

    International Nuclear Information System (INIS)

    Swinwood, J.F.; Kotler, J.

    1990-01-01

    This paper examines the financial viability of sewage sludge pasteurization by gamma radiation, by examining the following three North American scenarios: 1. Small volume sewage treatment plant experiencing high sludge disposal costs; 2. Large volume sewage treatment plant experiencing low sludge disposal costs; 3. Large volume sewage treatment plant experiencing high sludge disposal costs. (author)

  20. Comparison of methodologies for enumerating and detecting the viability of Ascaris eggs in sewage sludge by standard incubation-microscopy, the BacLight Live/Dead viability assay and other vital dyes.

    Science.gov (United States)

    Karkashan, Alaa; Khallaf, Basma; Morris, Jacqueline; Thurbon, Nerida; Rouch, Duncan; Smith, Stephen R; Deighton, Margaret

    2015-01-01

    The aim of this study was to evaluate the Live/Dead BacLight viability kit as a method for enumerating viable eggs of Ascaris suum in sewage sludge as a surrogate for the human roundworm. The number and viability status of eggs of A. suum were accurately measured directly in sewage sludge samples by the BacLight method, compared to the conventional incubation-microscopy procedure. BacLight stains were not toxic to A. suum eggs, in contrast to some conventional vital dyes which disrupted viable eggs. The method was effective for the direct examination of eggs in heavily contaminated samples or seeded sludge containing ∼200 eggs/g DS in sludge with 5% DS content. However, a recovery method would be necessary to examine samples with small numbers of eggs, for instance in sludge from regions where the prevalence of infection with Ascaris lumbricoides is low. The BacLight technique may therefore be an effective alternative to conventional incubation-microscopy for enumerating Ascaris eggs in contaminated field samples or to validate sludge treatment processes by examining decay rates of inoculated A. suum eggs in laboratory simulations. Most field samples would require recovery from an appropriate number of composite samples prior to vital staining.

  1. 75 FR 41886 - Recovery Plan for the Ivory-billed Woodpecker (Campephilus principalis)

    Science.gov (United States)

    2010-07-19

    ... ecosystems is a primary goal of our threatened and endangered species program. To help guide the recovery... focuses on learning more about the species' status and ecology, including documenting known locations and.... Analyze viability of any existing populations (numbers, breeding success, population genetics, and ecology...

  2. Recovery of phage lambda from ultraviolet damage

    International Nuclear Information System (INIS)

    Devoret, R.; Blanco, M.; George, J.; Radman, M.

    1975-01-01

    Recovery of phage lambda from ultraviolet damage can occur, in the dark, through three types of repair processes as defined by microbiological tests: host-cell reactivation, prophage reactivation, and uv reactivation. This paper reviews the properties of the three repair processes, analyzes their dependence on the functioning of bacterial and phage genes, and discusses their relationship. Progress in the understanding of the molecular mechanisms underlying the three repair processes has been relatively slow, particularly for uv reactivation. It has been shown that host-cell reactivation is due to pyrimidine dimer excision and that prophage reactivation is due to genetic recombination (prereplicative). We provide evidence showing that neither of these mechanisms accounts for uv reactivation of phage lambda. Furthermore, uv reactivation differs from the other repair processes in that it is inducible and error-prone. Whether uv-damaged bacterial DNA is subject to a similar repair process is still an open question

  3. Viability of L. casei during fermentation in soymilk and freeze-dried soymilk; effect of cryoprotectant, rehydration and storage temperature

    Directory of Open Access Journals (Sweden)

    Kristina Mladenovska

    2005-12-01

    Full Text Available The aim of the work was to investigate the behaviour of L. casei and the effect of sorbitol on its viability during fermentation in soymilk drink. Values for pH, ranging from 6.82 to 3.42 in the soymilk drink without sorbitol and from 6.74 to 3.41 in the drink with sorbitol were noted during 72 h of fermentation at 25oC. The corresponding values for titratable acidity ranged from 0.071% to 0.758% and from 0.073% to 0.761%, respectively. Soymilk was found to support the growth of L. casei with improvement in viability for 0.24 log at the end of fermentation when sorbitol was added. Survival of L. casei and the effectiveness of sorbitol in improving viability during freeze-drying, subsequent rehydration and during a 5-week period of storage under different temperatures were also investigated. After freeze-drying, L. casei exhibited a survival percent of approximately 46%. Sorbitol improved the viability of L. casei by 0.51 log immediately after freeze-drying and by 1.30 log and 0.47 log during five weeks of storage at 25oC and 4oC, respectively. Further study revealed that the freeze-dried fermented soymilk rehydrated at 45oC was optimum for the recovery of L. casei with improvement in recovery for 0.68 log when sorbitol was added. A higher percent of survival was noted when the dried soymilk was stored at 4oC than at 25oC with improved viability at the end of 5 weeks storage for approximately 6 log for drinks with and without sorbitol. Fermented dried soymilk with sorbitol afforded significant tolerance of L. casei to acid stress. Generally, a stable probiotic diary product was prepared in which the concentration of L. casei remained above therapeutic level of 107 cfu/ml.

  4. Viability and resistance of lactobacilli isolated from cocoa fermentation to simulated gastrointestinal digestive steps in soy yogurt.

    Science.gov (United States)

    Saito, V S T; Dos Santos, T F; Vinderola, C G; Romano, C; Nicoli, J R; Araújo, L S; Costa, M M; Andrioli, J L; Uetanabaro, A P T

    2014-02-01

    To study the potential probiotic characteristics such as decrease of pH, microbial viability, and tolerance to simulated digestive steps of fermented soy beverage ("soy yogurt") produced with lactobacilli isolated from cocoa fermentation (Lactobacillus fermentum TcUESC01 and Lactobacillus plantarum TcUESC02) during fermentation and refrigerated storage. The sensory acceptance of the yogurts was also tested. Samples of soy yogurt produced with L. fermentum TcUESC01 or L. plantarum TcUESC02 were collected during fermentation (0, 4, 8, and 12 h) and refrigerated storage (1, 9, 18, and 27 d), and submitted to pH and bacterial viability determinations. Tolerance to simulated digestion steps was done with refrigerated storage samples at 9 °C. Simulated digestion was performed in 3 successive steps: exposure to pepsin-HCl solution, bile shock, and simulated small intestinal juice. During storage, a decrease in pH and lactobacillus viability was observed. L. fermentum TcUESC01 showed to be more resistant than L. plantarum TcUESC02 to simulated gastrointestinal digestion. All soy yogurts showed acceptable hedonic scores (greater than 5 in a 9-point hedonic scale ranging from "like extremely" to "dislike extremely") in sensory evaluation for flavor, aroma, color, consistency, and overall impression. L. plantarum TcUESC02 and, especially, L. fermentum TcUESC01 showed potential probiotic characteristics when considering pH, cell viability, and tolerance to simulated digestive steps and did not affect the sensory characteristics when supplemented to soy yogurt during storage. © 2014 Institute of Food Technologists®

  5. Platelet storage at 22 degrees C: effect of type of agitation on morphology, viability, and function in vitro.

    Science.gov (United States)

    Holme, S; Vaidja, K; Murphy, S

    1978-08-01

    Recovery in vivo after 51Cr labeling, platelet morphology, and platelet aggregation were studied with platelet concentrates (PC) stored for transfusion under carefully controlled conditions. PC were prepared to a final volume of 50 ml from whole blood anticoagulated with citrate-phosphate-dextrose (CPD). The platelet count was kept between 0.8 and 1.6 X 10(12) platelets/liter. The PC were stored in bags constructed of polyvinylchloride (PVC) or polyethylene (PE) at 22 degrees C for 72 hr. The bags were placed on a horizontal shaker or a ferris wheel for agitation during storage. No significant changes in pH or platelet count were observed during storage. PC stored on the wheel showed moderate loss of viability and a marked deterioration of platelet morphology and aggregation compared to the shaker. PC stored on the shaker in bags made of PE showed better aggregation with ADP and thrombin but had the same viability and morphology as PC in bags constructed of PVC. Maintenance of normal platelet morphology as determined by phase-contrast microscopy, extent of shape change response, and the size distribution according to the Coulter Counter correlated with recovery in vivo.

  6. Effect of acclimation medium on cell viability, membrane integrity and ability to consume malic acid in synthetic wine by oenological Lactobacillus plantarum strains.

    Science.gov (United States)

    Bravo-Ferrada, B M; Tymczyszyn, E E; Gómez-Zavaglia, A; Semorile, L

    2014-02-01

    The aim of this work was to evaluate the effect of acclimation on the viability, membrane integrity and the ability to consume malic acid of three oenological strains of Lactobacillus plantarum. Cultures in the stationary phase were inoculated in an acclimation medium (Accl.) containing 0, 6 or 10% v/v ethanol and incubated 48 h at 28°C. After incubation, cells were harvested by centrifugation and inoculated in a synthetic wine, containing 14% v/v ethanol and pH 3.5 at 28°C. Viability and membrane integrity were determined by flow cytometry (FC) using carboxyfluorescein diacetate (cFDA) and propidium iodide. Bacterial growth and malic acid consumption were monitored in a synthetic wine during 15 days. In nonacclimated strains, the damage of bacterial membranes produced a dramatic decrease in microbial viability in synthetic wine. In contrast, survival of strains previously acclimated in Accl. with 6 and 10% v/v ethanol was noticeable higher. Therefore, acclimation with ethanol increased the cultivability in synthetic wine and consequently, the consumption of l-malic acid after 15 days of growth. Acclimation of oenological strains in media containing ethanol prior to wine inoculation significantly decreases the membrane damage and improves viability in the harsh wine conditions. The role of membrane integrity is crucial to warrant the degradation of l-malic acid. The efficiency of multiparametric FC in monitoring viability and membrane damage along with the malic acid consumption has a strong impact on winemaking because it represents a useful tool for a quick and highly reliable evaluation of oenological parameters. © 2013 The Society for Applied Microbiology.

  7. Bacterial Cell Mechanics.

    Science.gov (United States)

    Auer, George K; Weibel, Douglas B

    2017-07-25

    Cellular mechanical properties play an integral role in bacterial survival and adaptation. Historically, the bacterial cell wall and, in particular, the layer of polymeric material called the peptidoglycan were the elements to which cell mechanics could be primarily attributed. Disrupting the biochemical machinery that assembles the peptidoglycan (e.g., using the β-lactam family of antibiotics) alters the structure of this material, leads to mechanical defects, and results in cell lysis. Decades after the discovery of peptidoglycan-synthesizing enzymes, the mechanisms that underlie their positioning and regulation are still not entirely understood. In addition, recent evidence suggests a diverse group of other biochemical elements influence bacterial cell mechanics, may be regulated by new cellular mechanisms, and may be triggered in different environmental contexts to enable cell adaptation and survival. This review summarizes the contributions that different biomolecular components of the cell wall (e.g., lipopolysaccharides, wall and lipoteichoic acids, lipid bilayers, peptidoglycan, and proteins) make to Gram-negative and Gram-positive bacterial cell mechanics. We discuss the contribution of individual proteins and macromolecular complexes in cell mechanics and the tools that make it possible to quantitatively decipher the biochemical machinery that contributes to bacterial cell mechanics. Advances in this area may provide insight into new biology and influence the development of antibacterial chemotherapies.

  8. The role of coastal fog in increased viability of marine microbial aerosols

    Science.gov (United States)

    Dueker, M.; O'Mullan, G. D.; Weathers, K. C.; Juhl, A. R.; Uriarte, M.

    2011-12-01

    Microbes in the atmosphere (microbial aerosols) play an important role in climate and provide an ecological and biogeochemical connection between oceanic, atmospheric, and terrestrial environments. Despite the ubiquity of these bacteria (concentration estimates range from 1 x 10^4 to 6 x 10^5 cells m-3), much is still being learned about their source, viability, and interactions with climatic controls. They can be attached to ambient aerosol particles or exist singly in the air. They affect climate by serving as ice, cloud, and fog nucleators, and have the metabolic potential to alter atmospheric chemistry. Fog presence in particular has been shown to greatly increase the deposition of viable microbial aerosols in both urban and coastal environments, but the mechanisms behind this are not fully understood. To address this gap, we examined the diversity of culturable microbial aerosols from a relatively pristine coastal environment in Maine (USA) and determined the effect of fog presence on viability and community composition of microbial aerosols. 16S rRNA sequencing of culturable ocean surface bacteria and depositing microbial aerosols (under clear and foggy conditions) resulted in the detection of 31 bacterial genera, with 5 dominant genera (Vibrio, Bacillus, Pseudoalteromonas, Psychrobacter, Salinibacterium) making up 66% of all sequences. Seventy-five percent of the viable microbial aerosols falling out under foggy conditions were most similar to GenBank-published sequences detected in marine environments. The fog and ocean surface sequence libraries were significantly more similar in microbial community composition than clear (non-foggy) and ocean surface libraries. These findings support a dual role for fog in enhancing the fallout of viable marine microbial aerosols via increased gravitational settling rates and decreased aerosolization stress on the organisms. The dominant presence of marine bacteria in coastal microbial aerosols provides a strong case for

  9. Solvent recycle/recovery

    Energy Technology Data Exchange (ETDEWEB)

    Paffhausen, M.W.; Smith, D.L.; Ugaki, S.N.

    1990-09-01

    This report describes Phase I of the Solvent Recycle/Recovery Task of the DOE Chlorinated Solvent Substitution Program for the US Air Force by the Idaho National Engineering Laboratory, EG G Idaho, Inc., through the US Department of Energy, Idaho Operations Office. The purpose of the task is to identify and test recovery and recycling technologies for proposed substitution solvents identified by the Biodegradable Solvent Substitution Program and the Alternative Solvents/Technologies for Paint Stripping Program with the overall objective of minimizing hazardous wastes. A literature search to identify recycle/recovery technologies and initial distillation studies has been conducted. 4 refs.

  10. Bacterial meningitis in children

    International Nuclear Information System (INIS)

    Marji, S.

    2007-01-01

    To demonstrate the epidemiology, clinical manifestations and bacteriological profile of bacterial meningitis in children beyond the neonatal period in our hospital. This was a retrospective descriptive study conducted at Prince Rashid Hospital in Irbid, Jordan. The medical records of 50 children with the diagnosis of bacterial meningitis during 4 years period, were reviewed. The main cause of infection was streptococcus pneumoniae, followed by Haemophilus influenza and Niesseria meningitides. Mortality was higher in infants and meningococcal infection, while complications were more encountered in cases of streptococcus pneumoniae. Cerebrospinal fluid culture was positive in 11 cases and Latex agglutination test in 39. There is a significant reduction of the numbers of bacterial meningitis caused by Haemophilus influenza type B species. (author)

  11. Interfering with bacterial gossip

    DEFF Research Database (Denmark)

    Bjarnsholt, Thomas; Tolker-Nielsen, Tim; Givskov, Michael

    2011-01-01

    Biofilm resilience poses major challenges to the development of novel antimicrobial agents. Biofilm bacteria can be considered small groups of “Special Forces” capable of infiltrating the host and destroying important components of the cellular defense system with the aim of crippling the host...... defense. Antibiotics exhibit a rather limited effect on biofilms. Furthermore, antibiotics have an ‘inherent obsolescence’ because they select for development of resistance. Bacterial infections with origin in bacterial biofilms have become a serious threat in developed countries. Pseudomonas aeruginosa...... that appropriately target bacteria in their relevant habitat with the aim of mitigating their destructive impact on patients. In this review we describe molecular mechanisms involved in “bacterial gossip” (more scientifically referred to as quorum sensing (QS) and c-di-GMP signaling), virulence, biofilm formation...

  12. Diagnosis of bacterial vaginosis

    Directory of Open Access Journals (Sweden)

    Đukić Slobodanka

    2013-01-01

    Full Text Available Bacterial vaginosis is a common, complex clinical syndrome characterized by alterations in the normal vaginal flora. When symptomatic, it is associated with a malodorous vaginal discharge and on occasion vaginal burning or itching. Under normal conditions, lactobacilli constitute 95% of the bacteria in the vagina. Bacterial vaginosis is associated with severe reduction or absence of the normal H2O2­producing lactobacilli and overgrowth of anaerobic bacteria and Gardnerella vaginalis, Atopobium vaginae, Mycoplasma hominis and Mobiluncus species. Most types of infectious disease are diagnosed by culture, by isolating an antigen or RNA/DNA from the microbe, or by serodiagnosis to determine the presence of antibodies to the microbe. Therefore, demonstration of the presence of an infectious agent is often a necessary criterion for the diagnosis of the disease. This is not the case for bacterial vaginosis, since the ultimate cause of the disease is not yet known. There are a variety of methods for the diagnosis of bacterial vaginosis but no method can at present be regarded as the best. Diagnosing bacterial vaginosis has long been based on the clinical criteria of Amsel, whereby three of four defined criteria must be satisfied. Nugent’s scoring system has been further developed and includes validation of the categories of observable bacteria structures. Up­to­date molecular tests are introduced, and better understanding of vaginal microbiome, a clear definition for bacterial vaginosis, and short­term and long­term fluctuations in vaginal microflora will help to better define molecular tests within the broader clinical context.

  13. Adult bacterial meningitis

    DEFF Research Database (Denmark)

    Meyer, C N; Samuelsson, I S; Galle, M

    2004-01-01

    Episodes of adult bacterial meningitis (ABM) at a Danish hospital in 1991-2000 were identified from the databases of the Department of Clinical Microbiology, and compared with data from the Danish National Patient Register and the Danish National Notification System. Reduced penicillin susceptibi......Episodes of adult bacterial meningitis (ABM) at a Danish hospital in 1991-2000 were identified from the databases of the Department of Clinical Microbiology, and compared with data from the Danish National Patient Register and the Danish National Notification System. Reduced penicillin...

  14. Bacterial blight of cotton

    Directory of Open Access Journals (Sweden)

    Aïda JALLOUL

    2015-04-01

    Full Text Available Bacterial blight of cotton (Gossypium ssp., caused by Xanthomonas citri pathovar malvacearum, is a severe disease occurring in all cotton-growing areas. The interactions between host plants and the bacteria are based on the gene-for-gene concept, representing a complex resistance gene/avr gene system. In light of the recent data, this review focuses on the understanding of these interactions with emphasis on (1 the genetic basis for plant resistance and bacterial virulence, (2 physiological mechanisms involved in the hypersensitive response to the pathogen, including hormonal signaling, the oxylipin pathway, synthesis of antimicrobial molecules and alteration of host cell structures, and (3 control of the disease.

  15. Bacterial meningitis in infants.

    Science.gov (United States)

    Ku, Lawrence C; Boggess, Kim A; Cohen-Wolkowiez, Michael

    2015-03-01

    Neonatal bacterial meningitis is uncommon but devastating. Morbidity among survivors remains high. The types and distribution of pathogens are related to gestational age, postnatal age, and geographic region. Confirming the diagnosis is difficult. Clinical signs are often subtle, lumbar punctures are frequently deferred, and cerebrospinal fluid (CSF) cultures can be compromised by prior antibiotic exposure. Infants with bacterial meningitis can have negative blood cultures and normal CSF parameters. Promising tests such as the polymerase chain reaction require further study. Prompt treatment with antibiotics is essential. Clinical trials investigating a vaccine for preventing neonatal Group B Streptococcus infections are ongoing. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Cosmological viability conditions for f(T) dark energy models

    Energy Technology Data Exchange (ETDEWEB)

    Setare, M.R.; Mohammadipour, N., E-mail: rezakord@ipm.ir, E-mail: N.Mohammadipour@uok.ac.ir [Department of Science, University of Kurdistan, Sanandaj (Iran, Islamic Republic of)

    2012-11-01

    Recently f(T) modified teleparallel gravity where T is the torsion scalar has been proposed as the natural gravitational alternative for dark energy. We perform a detailed dynamical analysis of these models and find conditions for the cosmological viability of f(T) dark energy models as geometrical constraints on the derivatives of these models. We show that in the phase space exists two cosmologically viable trajectory which (i) The universe would start from an unstable radiation point, then pass a saddle standard matter point which is followed by accelerated expansion de sitter point. (ii) The universe starts from a saddle radiation epoch, then falls onto the stable matter era and the system can not evolve to the dark energy dominated epoch. Finally, for a number of f(T) dark energy models were proposed in the more literature, the viability conditions are investigated.

  17. Traffic networks as information systems a viability approach

    CERN Document Server

    Aubin, Jean-Pierre

    2017-01-01

    This authored monograph covers a viability to approach to traffic management by advising to vehicles circulated on the network the velocity they should follow for satisfying global traffic conditions;. It presents an investigation of three structural innovations: The objective is to broadcast at each instant and at each position the advised celerity to vehicles, which could be read by auxiliary speedometers or used by cruise control devices. Namely, 1. Construct regulation feedback providing at each time and position advised velocities (celerities) for minimizing congestion or other requirements. 2. Taking into account traffic constraints of different type, the first one being to remain on the roads, to stop at junctions, etc. 3. Use information provided by the probe vehicles equipped with GPS to the traffic regulator; 4. Use other global traffic measures of vehicles provided by different types of sensors; These results are based on convex analysis, intertemporal optimization and viability theory as mathemati...

  18. Nuclear Power Options Viability Study. Volume 4. Bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Trauger, D B; White, J D; Sims, J W [eds.

    1986-09-01

    Documents in the Nuclear Power Options Viability Study (NPOVS) bibliography are classified under one of four headings or categories as follows: nuclear options; light water reactors; liquid metal reactors; and high temperature reactors. The collection and selection of these documents, beginning early in 1984 and continuing through March of 1986, was carried out in support of the study's objective: to explore the viabilities of several nuclear electric power generation options for commercial deployment in the United States between 2000 and 2010. There are approximately 550 articles, papers, reports, and books in the bibliography that have been selected from some 2000 surveyed. The citations have been made computer accessible to facilitate rapid on-line retrieval by keyword, author, corporate author, title, journal name, or document number.

  19. Usefulness of radionuclide scintiphotography to evaluate preserved kidney viability

    International Nuclear Information System (INIS)

    Sato, Koshi; Yokota, Kazuhiko; Uchida, Hisanori

    1987-01-01

    GAMMA imaging of the renal cortical microcirculation is a safe and non-invasive method for assessment of kidney viability before transplantation. We used trifluoperazine (TFP), urokinase and verapamil from 24 to 120 hour kidney preservation in dogs. For these preserved kidneys, we used radionuuclide scintiphotography to evaluate kidney viability. After preservation, these kidneys were perfused with technitium -99m labeled microspheres, and imaging of the renal vasculature was obtained by scintigraphy. The distribution of the microspheres was assessed visually and by computer analysis. Modified Collins' solution perfused kidneys show very poor cortical uptake with marked increase in uptake in the hilar region after preservation. In contrast, cortical flow remained relatively well preserved in kidneys perfused and preserved by use of modified Collins' solotion with TFP, urokinase and urokinase + verapamil. There was a direct correlation between these results and the capacity of kidneys treated in the same fashion to sustain life after retransplantation into the original host. (author)

  20. Cost viability of 3D printed house in UK

    Science.gov (United States)

    Tobi, A. L. Mohd; Omar, S. A.; Yehia, Z.; Al-Ojaili, S.; Hashim, A.; Orhan, O.

    2018-03-01

    UK has been facing housing crisis due to the rising price of the property on sale. This paper will look into the viability of 3D printing technology as an alternative way for house construction on UK. The analysis will be carried out based on the data until the year of 2014 due to limited resources availability. Details cost breakdown on average size house construction cost in UK were analysed and relate to the cost viability of 3D printing technology in reducing the house price in UK. It is found that the 3D printing generates saving of up to around 35% out of total house price in UK. This cost saving comes from the 3D printed construction of walls and foundations for material and labour cost.

  1. Nuclear Power Options Viability Study. Volume 4. Bibliography

    International Nuclear Information System (INIS)

    Trauger, D.B.; White, J.D.; Sims, J.W.

    1986-09-01

    Documents in the Nuclear Power Options Viability Study (NPOVS) bibliography are classified under one of four headings or categories as follows: nuclear options; light water reactors; liquid metal reactors; and high temperature reactors. The collection and selection of these documents, beginning early in 1984 and continuing through March of 1986, was carried out in support of the study's objective: to explore the viabilities of several nuclear electric power generation options for commercial deployment in the United States between 2000 and 2010. There are approximately 550 articles, papers, reports, and books in the bibliography that have been selected from some 2000 surveyed. The citations have been made computer accessible to facilitate rapid on-line retrieval by keyword, author, corporate author, title, journal name, or document number

  2. VIABILITY OF THE PROBIOTIC BACTERIA L. ACIDOPHILUS IN DAIRY PRODUCTS

    Directory of Open Access Journals (Sweden)

    Janka Koreňová

    2011-12-01

    Full Text Available A number of health benefits have been claimed for probiotic bacteria such as Lactobacillus acidophilus. Because of the potential health benefits, these organisms are increasingly incorporated into dairy foods. Viability of probiotic bacteria is important in order to provide health benefits. However, many studies have shown low viability of probiotics in market preparations. This study cover selective enumeration and survival of probiotic bacteria L. acidophilus in some dairy drinks. L. acidophilus was found in the range from 106 to 107 CFU.g-1 in five types of fermented milk products containing probiotic cultures. Two investigated products were up to standard according to Regulation of Ministry of Agriculture and Ministry of Health of Slovak Republic.doi: 10.5219/147

  3. Viability of human corneal keratocytes during organ culture

    DEFF Research Database (Denmark)

    Møller-Pedersen, T; Møller, H J

    1996-01-01

    The viability of human corneal keratocytes was assessed during four weeks of 'closed system' organ culture at 31 degrees C. After 28 days of culturing, the entire keratocyte population was still alive and viable because all cells incorporated uridine; a parameter for RNA-synthesis. During the fir...... of keratan sulphate proteoglycan suggested that approximately 1% of the total content was lost during the period. In conclusion, our current organ culture technique can maintain a viable keratocyte population for four weeks; a viable stroma can be grafted within this period.......The viability of human corneal keratocytes was assessed during four weeks of 'closed system' organ culture at 31 degrees C. After 28 days of culturing, the entire keratocyte population was still alive and viable because all cells incorporated uridine; a parameter for RNA-synthesis. During the first...

  4. Determination of intestinal viability by Doppler ultrasonography in venous infarction.

    Science.gov (United States)

    Cooperman, M; Martin, E W; Carey, L C

    1980-01-01

    The accuracy of Doppler ultrasound in predicting the viability of ischemic intestine secondary to venous obstruction was assessed. Twenty loops of ischemic intestine were created in dogs by temporarily obstructing venous return from the bowel. Doppler arterial flow signals within the intestine quickly disappeared following venous occlusion. In ten segments, arterial signals promptly returned following release of venous occlusion. Nine of these ten segments were viable at reoperation 24 hours later. In ten segments, no arterial signals could be detected following release of venous occlusion, and only one segment proved to be viable. Doppler ultrasound findings were far more accurate in distinguishing between viable and nonviable intestine thatn were clinical guides to intestinal viability. PMID:7352777

  5. Structural Aspects of Bacterial Outer Membrane Protein Assembly.

    Science.gov (United States)

    Calmettes, Charles; Judd, Andrew; Moraes, Trevor F

    2015-01-01

    The outer membrane of Gram-negative bacteria is predominantly populated by β-Barrel proteins and lipid anchored proteins that serve a variety of biological functions. The proper folding and assembly of these proteins is essential for bacterial viability and often plays a critical role in virulence and pathogenesis. The β-barrel assembly machinery (Bam) complex is responsible for the proper assembly of β-barrels into the outer membrane of Gram-negative bacteria, whereas the localization of lipoproteins (Lol) system is required for proper targeting of lipoproteins to the outer membrane.

  6. Economic viability of biogas technology in a Bangladesh village

    International Nuclear Information System (INIS)

    Biswas, W.K.; Lucas, N.J.D.

    1997-01-01

    We estimate energy consumption for domestic cooking and biogas energy resources for 21 clusters of households in a village. Data were analyzed on a cluster basis, with investments shared. Under the present conditions, biogas technology would not be economically viable. Economic analysis involving viability tools including additional benefits of biogas technology indicate that creating a market for local biogas would make such a project feasible. (Author)

  7. Effect of Isolation Techniques on Viability of Bovine Blood Neutrophils

    Directory of Open Access Journals (Sweden)

    P. Sláma

    2006-01-01

    Full Text Available The effect of selected isolation methods on the viability of neutrophil granulocytes (neutrophils from the blood of healthy Holstein x Bohemian Red Pied crossbred heifers was evaluated. Two methods of neutrophil isolation were used: a neutrophil isolation on the basis of hypotonic erythrocyte lysis (in two variants: after the erythrocyte lysis proper, the cells were centrifuged at either 200 g or 1000 g, and b neutrophil isolation with FACS Lysing Solution as the lysing agent. The viability of the isolated neutrophils was evaluated on the basis of apoptosis and necrosis. The results obtained with flow cytometry (FCM suggest that, from the isolation techniques used, the method based on FACS Lysing Solution impaired the neutrophil viability least. After the application of this method, 5.36 ± 2.15% of neutrophils were apoptotic and 0.51 ± 0.12% were necrotic. In contrast, when the hypotonic erythrocyte lysis was used, the proportion of apoptotic neutrophils amounted to 42.14 ± 7.12% and 49.00 ± 14.70%, respectively, and 41.12 ± 5.55% and 36.91 ± 24.38% respectively of necrotic neutrophils (P < 0.01. This was also confirmed by the light microscopy. After the isolation with FASC Lysing Solution, 1.92 ± 1.74% of neutrophils were apoptotic and 1.05 ± 0.76% were necrotic, as distinct from after the hypotonic erythrocyte lysis where 9.43 ± 3.69% of neutrophils were apoptotic and 12.67 ± 4.74% of necrotic after centrifugation at 200 g, while 12.60 ± 4.35 were apoptotic and 14.96 ± 12.64% were necrotic after centrifugation at 1000 g. It follows from the above-mentioned data that hypotonic lysis is not a suitable method for the isolation of neutrophils, as the method itself markedly affects cell viability.

  8. Assessing population viability while accounting for demographic and environmental uncertainty.

    Science.gov (United States)

    Oppel, Steffen; Hilton, Geoff; Ratcliffe, Norman; Fenton, Calvin; Daley, James; Gray, Gerard; Vickery, Juliet; Gibbons, David

    2014-07-01

    Predicting the future trend and viability of populations is an essential task in ecology. Because many populations respond to changing environments, uncertainty surrounding environmental responses must be incorporated into population assessments. However, understanding the effects of environmental variation on population dynamics requires information on several important demographic parameters that are often difficult to estimate. Integrated population models facilitate the integration of time series data on population size and all existing demographic information from a species, allowing the estimation of demographic parameters for which limited or no empirical data exist. Although these models are ideal for assessments of population viability, they have so far not included environmental uncertainty. We incorporated environmental variation in an integrated population model to account for both demographic and environmental uncertainty in an assessment of population viability. In addition, we used this model to estimate true juvenile survival, an important demographic parameter for population dynamics that is difficult to estimate empirically. We applied this model to assess the past and future population trend of a rare island endemic songbird, the Montserrat Oriole Icterus oberi, which is threatened by volcanic activity. Montserrat Orioles experienced lower survival in years with volcanic ashfall, causing periodic population declines that were compensated by higher seasonal fecundity in years with high pre-breeding season rainfall. Due to the inclusion of both demographic and environmental uncertainty in the model, the estimated population growth rate in the immediate future was highly imprecise (95% credible interval 0.844-1.105), and the probability of extinction after three generations (in the year 2028) was low (2.1%). This projection demonstrates that accounting for both demographic and environmental sources of uncertainty provides a more realistic assessment

  9. Viability of Trichomonas vaginalis in vitro at four temperatures.

    OpenAIRE

    Smith, R F

    1983-01-01

    The effect of temperature as a possible factor on the survival of Trichomonas vaginalis for shipment or routine laboratory maintenance was studied. Ten strains of T. vaginalis, ATCC 30001, ATCC 30238, and eight clinical isolates, were examined for viability when kept incubated at 37 degrees C or removed from this temperature and held at 42, 22, or 5 degrees C for increasing lengths of time without subculture or reincubation at 37 degrees C. The order in which the strains remained viable witho...

  10. Edible flowers - antioxidant activity and impact on cell viability

    OpenAIRE

    Kuceková, Zdenka; Mlček, Jiří; Humpolíček, Petr; Rop, Otakar

    2013-01-01

    The phenolic compound composition, antioxidant activity and impact on cell viability of edible flower extracts of Allium schoenoprasum; Bellis perennis; Cichorium intybus; Rumex acetosa; Salvia pratensis; Sambucus nigra; Taraxacum officinale; Tragopogon pratensis; Trifolium repens and Viola arvensis was examined for the first time. Total phenolic content of the flowers of these plants fell between 11.72 and 42.74 mg of tannin equivalents/kg of dry matter. Antioxidant activity ranged from 35.5...

  11. In vitro pollen quantity, viability and germination tests in quince

    African Journals Online (AJOL)

    use

    2011-11-21

    Nov 21, 2011 ... The germination rates in different sucrose and boric acid concentrations in 1% agar changed from 0 ('Limon' in 0% sucrose) to 91.7% ('Ege 2' in 20% sucrose) and from 32.7 (Quince A in 0 mg/L boric acid) to 94.9% ('Ege 22' in 100 mg/L boric acid), respectively. Key words: Cydonia oblonga, pollen, viability ...

  12. FEMA Disaster Recovery Centers

    Data.gov (United States)

    Department of Homeland Security — This is a search site for FEMA's Disaster Recovery Centers (DRC). A DRC is a readily accessible facility or mobile office set up by FEMA where applicants may go for...

  13. Recovery Audit Program

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Recovery Audit Programs mission is to identify and correct Medicare improper payments through the efficient detection and collection of overpayments made on...

  14. Recovery Action Mapping Tool

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Recovery Action Mapping Tool is a web map that allows users to visually interact with and query actions that were developed to recover species listed under the...

  15. Inhibiting ice recrystallization and optimization of cell viability after cryopreservation.

    Science.gov (United States)

    Chaytor, Jennifer L; Tokarew, Jacqueline M; Wu, Luke K; Leclère, Mathieu; Tam, Roger Y; Capicciotti, Chantelle J; Guolla, Louise; von Moos, Elisabeth; Findlay, C Scott; Allan, David S; Ben, Robert N

    2012-01-01

    The ice recrystallization inhibition activity of various mono- and disaccharides has been correlated with their ability to cryopreserve human cell lines at various concentrations. Cell viabilities after cryopreservation were compared with control experiments where cells were cryopreserved with dimethylsulfoxide (DMSO). The most potent inhibitors of ice recrystallization were 220 mM solutions of disaccharides; however, the best cell viability was obtained when a 200 mM d-galactose solution was utilized. This solution was minimally cytotoxic at physiological temperature and effectively preserved cells during freeze-thaw. In fact, this carbohydrate was just as effective as a 5% DMSO solution. Further studies indicated that the cryoprotective benefit of d-galactose was a result of its internalization and its ability to mitigate osmotic stress, prevent intracellular ice formation and/or inhibit ice recrystallization. This study supports the hypothesis that the ability of a cryoprotectant to inhibit ice recrystallization is an important property to enhance cell viability post-freeze-thaw. This cryoprotective benefit is observed in three different human cell lines. Furthermore, we demonstrated that the ability of a potential cryoprotectant to inhibit ice recrystallation may be used as a predictor of its ability to preserve cells at subzero temperatures.

  16. Dormancy, activation and viability of Rhizopus oligosporus sporangiospores.

    Science.gov (United States)

    Thanh, N V; Nout, M J R

    2004-04-15

    Interruption of dormancy to improve viability of Rhizopus oligosporus sporangiospores is crucial for the application of stored starter cultures for fungal (tempe) production. We aimed to assess the extent of dormancy and factors that could result in activation. Whereas heat treatments were unsuccessful, Malt Extract Broth (MEB) showed to be a good activation medium, with 80% of dormant spores being activated as measured by fluorescence microscopy using a fluorescent marker, compared with 11% with the control. Peptone and yeast extract but not glucose played an important role in activating dormant spores. Metabolically active (fluorescent) and swollen spores, followed by germ tubes were obtained after activation in MEB for 25 min., 2 and 4 h, respectively, at 37 degrees C. Simultaneously, some interesting transitions took place. Dormant spores represent 85-90% of the total spores at harvest and after drying. Their number decreased to 21-32% after activation with MEB with a concomitant increase of metabolically active spores. As a result of storage, some dormancy was lost, yielding an increase of active spores from 11.2% at harvest to 28.8% after 3 months storage. Levels of active spores were well correlated with their viability. By activation of dormant spores, their viability increased; levels of viable and active spores were maximum in 1 month old starter (61.7% and 75.9% of total spores, respectively) but gradually decreased with concomitant increase of the number of dead spores.

  17. Ca-Lignosulphonate and sclerotial viability of Sclerotinia sclerotiorum

    Directory of Open Access Journals (Sweden)

    MATTEO MONTANARI

    2012-01-01

    Full Text Available Lignosulphonates, low cost by-products of the pulping process, have shown suppressive effects against some diseases caused by soil-borne pathogens. In this study, the effect of 1.5% v/v calcium lignosulphonate (Ca-Ls amendment to two commercial potting mixes (peat + coconut fibres; PC; and municipal compost + peat + pumice; MCPP on the viability of Sclerotinia sclerotiorum sclerotia was investigated. Sclerotia were buried in the Ca-Ls amended substrates for 30 days. Non-amended PC and MCPP, sterile sand and sterile PC with and without Ca-Ls were used as controls. The viability of sclerotia recovered from PC and MCPP amended with Ca-Ls was reduced by 50 and 42% respectively compared to control treatments. Ca-Ls amendment decreased sclerotial viability by enhancing the activity of the indigenous mycoparasitic fungi, Fusarium oxysporum, Mucor spp. and Trichoderma spp. The biocontrol ability of Ca-Ls against sclerotia was due to the stimulation of microbial activity and is, therefore, strictly dependent on the microbial composition of the substrate.

  18. Efficacy of Zingiber officinale ethanol extract on the viability, embryogenesis and infectivity of Toxocara canis eggs.

    Science.gov (United States)

    El-Sayed, Nagwa Mostafa

    2017-12-01

    This study evaluated the effect of Zingiber officinal e ( Z. officinal e) ethanol extract on the viability, embryogenesis and infectivity Toxocara canis ( T. canis ) eggs. It was carried out both in vitro and in vivo. In the in vitro experiment, unembryonated T. canis eggs were incubated with 25, 50 and 100 mg/mL Z. officinal e extract at 25 °C for 6, 12, and 24 h to assess the effect of Z. officinal e on their viability and for two weeks to assess the effect of Z. officinal e on their embryogenesis. In vivo experiment was performed to assess the effect of Z. officinal e on infectivity of T. canis eggs. Treated embryonated eggs by Z. officinale extract at concentrations of 25, 50 and 100 mg/mL for 24 h were inoculated into mice and their livers were examined for the presence of T. canis larvae on the 7th day after infection and for histopathological evaluation at 14th day post-infection. Z. officinal e showed a significant ovicidal activity on T. canis eggs. The best effect was observed with 100 mg/mL concentration after 24 h with an efficacy of 98.2%. However, the treated eggs by 25, 50 mg/mL of Z. officinale extract after 24 h showed ovicidal activity by 59.22 and 82.5% respectively. Moreover, this extract effectively inhibited T. canis eggs embryogenesis by 99.64% and caused their degeneration at the concentration of 100 mg/mL after 2 weeks of treatment. However, the lower concentrations, 25 and 50 mg/mL inhibited embryogenesis by 51.19 and 78.57% respectively. The effect of Z. officinal e on the infectivity T. canis eggs was proven by the reduction of larvae recovery in the livers by 35.9, 62.8 and 89.5% in mice groups inoculated by Z. officinale treated eggs at concentrations of 25, 50 and 100 mg/mL respectively. Histopathologically, the liver tissues of mice infected with Z. officinale treated eggs at the concentration of 100 mg/mL appeared healthy with slight degenerative changes of hepatocytes, opposite to that recorded in the infected mice

  19. [Mondini dysplasia: recurrent bacterial meningitis in adolescence].

    Science.gov (United States)

    Vargas-Dĭaz, J; Garófalo-Gómez, N; Rodríguez, U; Parra, M; Barroso-García, E; Novoa-López, L; Rojas-Massipe, E; Sardiñas-Hernández, N L

    Episodes of recurrent bacterial meningitis can occur in patients due to either congenital or acquired disorders. Congenital deformity of the bony labyrinth can be linked to a fistulous tract communicating it with the intracranial subarachnoid space. Mondini deformity is a frequent malformation in congenitally deaf patients. We report the case of an adolescent with a history of being unable to hear in one ear who, from the age of 10 years, began to suffer repeated bacterial meningoencephalitis with microbiological recovery of Streptococcus pneumoniae on three occasions. The type of germ recovered in the cerebrospinal fluid (CSF) and the history of congenital deafness that was detected when the patient was 3 years old were the diagnostic clues to the possible anomaly of the inner ear with a CSF fistula. The clinically proven CSF rhinorrhea contributed to the diagnosis of an ear anomaly with a fistula. Computerised axial tomography and magnetic resonance studies of the petrous portion of the temporal bone revealed the malformation that was later found and closed during the surgical intervention on the affected ear. The clinical absence of rhinorrhea, a year's progression without new infections after operating on the patient and post-surgery imaging studies were all proof that the fistula had closed. Mondini dysplasia with CSF fistula must be included as a possible diagnosis when faced with a patient with recurrent bacterial meningoencephalitis. Imaging studies, especially magnetic resonance, enable the clinician to check the diagnosis and the CSF fistula can be closed with ear surgery.

  20. The Bacterial Growth Curve.

    Science.gov (United States)

    Paulton, Richard J. L.

    1991-01-01

    A procedure that allows students to view an entire bacterial growth curve during a two- to three-hour student laboratory period is described. Observations of the lag phase, logarithmic phase, maximum stationary phase, and phase of decline are possible. A nonpathogenic, marine bacterium is used in the investigation. (KR)

  1. Bacterial fingerprints across Europe

    NARCIS (Netherlands)

    Glasner, Corinna

    2014-01-01

    Bacterial pathogens, such as Staphylococcus aureus and carbapenemase-producing Enterobacteriaceae (CPE), impose major threats to human health worldwide. Both have a ‘Jekyll & Hyde’ character, since they can be present as human commensals, but can also become harmful invasive pathogens especially

  2. [Bacterial biofilms and infection].

    Science.gov (United States)

    Lasa, I; Del Pozo, J L; Penadés, J R; Leiva, J

    2005-01-01

    In developed countries we tend to think of heart disease and the numerous forms of cancer as the main causes of mortality, but on a global scale infectious diseases come close, or may even be ahead: 14.9 million deaths in 2002 compared to cardiovascular diseases (16.9 million deaths) and cancer (7.1 million deaths) (WHO report 2004). The infectious agents responsible for human mortality have evolved as medical techniques and hygienic measures have changed. Modern-day acute infectious diseases caused by specialized bacterial pathogens such as diphtheria, tetanus, cholera, plague, which represented the main causes of death at the beginning of XX century, have been effectively controlled with antibiotics and vaccines. In their place, more than half of the infectious diseases that affect mildly immunocompromised patients involve bacterial species that are commensal with the human body; these can produce chronic infections, are resistant to antimicrobial agents and there is no effective vaccine against them. Examples of these infections are the otitis media, native valve endocarditis, chronic urinary infections, bacterial prostatitis, osteomyelitis and all the infections related to medical devices. Direct analysis of the surface of medical devices or of tissues that have been foci of chronic infections shows the presence of large numbers of bacteria surrounded by an exopolysaccharide matrix, which has been named the "biofilm". Inside the biofilm, bacteria grow protected from the action of the antibodies, phagocytic cells and antimicrobial treatments. In this article, we describe the role of bacterial biofilms in human persistent infections.

  3. EDITORIAL SPONTANEOUS BACTERIAL PERITONITIS ...

    African Journals Online (AJOL)

    hi-tech

    Spontaneous bacterial peritonitis (SBP) frequent]y occurs in patients with liver cirrhosis and ascites. It is defined as an infection of previously sterile ascitic fluid without any demonstrable intrabdominal source of infection. It is now internationally agreed that a polymorphonuclear (PMN) cell count in the ascitic fluid of over 250 ...

  4. Bacterial membrane proteomics.

    Science.gov (United States)

    Poetsch, Ansgar; Wolters, Dirk

    2008-10-01

    About one quarter to one third of all bacterial genes encode proteins of the inner or outer bacterial membrane. These proteins perform essential physiological functions, such as the import or export of metabolites, the homeostasis of metal ions, the extrusion of toxic substances or antibiotics, and the generation or conversion of energy. The last years have witnessed completion of a plethora of whole-genome sequences of bacteria important for biotechnology or medicine, which is the foundation for proteome and other functional genome analyses. In this review, we discuss the challenges in membrane proteome analysis, starting from sample preparation and leading to MS-data analysis and quantification. The current state of available proteomics technologies as well as their advantages and disadvantages will be described with a focus on shotgun proteomics. Then, we will briefly introduce the most abundant proteins and protein families present in bacterial membranes before bacterial membrane proteomics studies of the last years will be presented. It will be shown how these works enlarged our knowledge about the physiological adaptations that take place in bacteria during fine chemical production, bioremediation, protein overexpression, and during infections. Furthermore, several examples from literature demonstrate the suitability of membrane proteomics for the identification of antigens and different pathogenic strains, as well as the elucidation of membrane protein structure and function.

  5. Seizures Complicating Bacterial Meningitis

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2004-09-01

    Full Text Available The clinical data of 116 patients, 1 month to <5 years of age, admitted for bacterial meningitis, and grouped according to those with and without seizures during hospitalization, were compared in a study at Buddhist Dalin Tzu Chi General Hospital, Chang Gung Memorial Hospital and other centers in Taiwan.

  6. Diagnosis of bacterial infection

    African Journals Online (AJOL)

    rapid and easy-to-use test for bacterial infections. Clearly, this is a very ... detect antigens or specific antibodies, e.g. group A streptococcal antigen testing can be employed to reduce antibiotic use. Culture-based tests are often ... White blood cell count 12 000 cells/mm³; or the presence of >10% ...

  7. Bacterial Meningitis Outcome

    OpenAIRE

    J Gordon Millichap

    1995-01-01

    The neurologic, psychological, and educational outcomes of bacterial meningitis in 130 children evaluated at a mean age of 8 years, and 6 years after their meningitis, are reported from the Department of Paediatrics and Clinical Epidemiology and Biostatistics Unit, University of Melbourne, and the Royal Children’s Hospital, Victoria, Australia.

  8. A framework for developing objective and measurable recovery criteria for threatened and endangered species.

    Science.gov (United States)

    Himes Boor, Gina K

    2014-02-01

    For species listed under the U.S. Endangered Species Act (ESA), the U.S. Fish and Wildlife Service and National Marine Fisheries Service are tasked with writing recovery plans that include "objective, measurable criteria" that define when a species is no longer at risk of extinction, but neither the act itself nor agency guidelines provide an explicit definition of objective, measurable criteria. Past reviews of recovery plans, including one published in 2012, show that many criteria lack quantitative metrics with clear biological rationale and are not meeting the measureable and objective mandate. I reviewed how objective, measureable criteria have been defined implicitly and explicitly in peer-reviewed literature, the ESA, other U.S. statutes, and legal decisions. Based on a synthesis of these sources, I propose the following 6 standards be used as minimum requirements for objective, measurable criteria: contain a quantitative threshold with calculable units, stipulate a timeframe over which they must be met, explicitly define the spatial extent or population to which they apply, specify a sampling procedure that includes sample size, specify a statistical significance level, and include justification by providing scientific evidence that the criteria define a species whose extinction risk has been reduced to the desired level. To meet these 6 standards, I suggest that recovery plans be explicitly guided by and organized around a population viability modeling framework even if data or agency resources are too limited to complete a viability model. When data and resources are available, recovery criteria can be developed from the population viability model results, but when data and resources are insufficient for model implementation, extinction risk thresholds can be used as criteria. A recovery-planning approach centered on viability modeling will also yield appropriately focused data-acquisition and monitoring plans and will facilitate a seamless transition

  9. Corticosteroids for Bacterial Keratitis

    Science.gov (United States)

    Srinivasan, Muthiah; Mascarenhas, Jeena; Rajaraman, Revathi; Ravindran, Meenakshi; Lalitha, Prajna; Glidden, David V.; Ray, Kathryn J.; Hong, Kevin C.; Oldenburg, Catherine E.; Lee, Salena M.; Zegans, Michael E.; McLeod, Stephen D.; Lietman, Thomas M.; Acharya, Nisha R.

    2013-01-01

    Objective To determine whether there is a benefit in clinical outcomes with the use of topical corticosteroids as adjunctive therapy in the treatment of bacterial corneal ulcers. Methods Randomized, placebo-controlled, double-masked, multicenter clinical trial comparing prednisolone sodium phosphate, 1.0%, to placebo as adjunctive therapy for the treatment of bacterial corneal ulcers. Eligible patients had a culture-positive bacterial corneal ulcer and received topical moxifloxacin for at least 48 hours before randomization. Main Outcome Measures The primary outcome was best spectacle-corrected visual acuity (BSCVA) at 3 months from enrollment. Secondary outcomes included infiltrate/scar size, reepithelialization, and corneal perforation. Results Between September 1, 2006, and February 22, 2010, 1769 patients were screened for the trial and 500 patients were enrolled. No significant difference was observed in the 3-month BSCVA (−0.009 logarithm of the minimum angle of resolution [logMAR]; 95% CI, −0.085 to 0.068; P = .82), infiltrate/scar size (P = .40), time to reepithelialization (P = .44), or corneal perforation (P > .99). A significant effect of corticosteroids was observed in subgroups of baseline BSCVA (P = .03) and ulcer location (P = .04). At 3 months, patients with vision of counting fingers or worse at baseline had 0.17 logMAR better visual acuity with corticosteroids (95% CI, −0.31 to −0.02; P = .03) compared with placebo, and patients with ulcers that were completely central at baseline had 0.20 logMAR better visual acuity with corticosteroids (−0.37 to −0.04; P = .02). Conclusions We found no overall difference in 3-month BSCVA and no safety concerns with adjunctive corticosteroid therapy for bacterial corneal ulcers. Application to Clinical Practice Adjunctive topical corticosteroid use does not improve 3-month vision in patients with bacterial corneal ulcers. PMID:21987582

  10. Uranium recovery from slags of metallic uranium

    International Nuclear Information System (INIS)

    Fornarolo, F.; Frajndlich, E.U.C.; Durazzo, M.

    2006-01-01

    The Center of the Nuclear Fuel of the Institute of Nuclear Energy Research - IPEN finished the program of attainment of fuel development for research reactors the base of Uranium Scilicet (U 3 Si 2 ) from Hexafluoride of Uranium (UF 6 ) with enrichment 20% in weight of 235 U. In the process of attainment of the league of U 3 Si 2 we have as Uranium intermediate product the metallic one whose attainment generates a slag contend Uranium. The present work shows the results gotten in the process of recovery of Uranium in slags of calcined slags of Uranium metallic. Uranium the metallic one is unstable, pyrophoricity and extremely reactive, whereas the U 3 O 8 is a steady oxide of low chemical reactivity, what it justifies the process of calcination of slags of Uranium metallic. The calcination of the Uranium slag of the metallic one in oxygen presence reduces Uranium metallic the U 3 O 8 . Experiments had been developed varying it of acid for Uranium control and excess, nitric molar concentration gram with regard to the stoichiometric leaching reaction of temperature of the leaching process. The 96,0% income proves the viability of the recovery process of slags of Uranium metallic, adopting it previous calcination of these slags in nitric way with low acid concentration and low temperature of leaching. (author)

  11. Influence of microencapsulation and spray drying on the viability of Lactobacillus and Bifidobacterium strains.

    Science.gov (United States)

    Goderska, Kamila; Czarnecki, Zbigniew

    2008-01-01

    Improved production methods of starter cultures, which constitute the most important element of probiotic preparations, were investigated. The aim of the presented research was to analyse changes in the viability of Lactobacillus. acidophilus and Bifidobacterium bifidum after stabilization (spray drying, liophilization, fluidization drying) and storage in refrigerated conditions for 4 months. The highest numbers of live cells, up to the fourth month of storage in refrigerated conditions, of the order of 10(7) cfu/g preparation were recorded for the B. bifidum DSM 20239 bacteria in which the N-Tack starch for spray drying was applied. Fluidization drying of encapsulated bacteria allowed obtaining a preparation of the comparable number of live bacterial cells up to the fourth month of storage with those encapsulated bacteria, which were subjected to freeze-drying but the former process was much shorter. The highest survivability of the encapsulated L. acidophilus DSM 20079 and B. bifidum DSM 20239 cells subjected to freeze-drying was obtained using skimmed milk as the cryoprotective substance. Stabilization of bacteria by microencapsulation can give a product easy to store and apply to produce dried food composition.

  12. Continuous Excretion of Leptospira borgpetersenii Ballum in Mice Assessed by Viability Quantitative Polymerase Chain Reaction.

    Science.gov (United States)

    Soupé-Gilbert, Marie-Estelle; Bierque, Emilie; Geroult, Sophie; Teurlai, Magali; Goarant, Cyrille

    2017-10-01

    Rodents are the main reservoir animals of leptospirosis. In this study, we characterized and quantified the urinary excretion dynamics of Leptospira by Mus musculus infected with 2 × 10 8 virulent Leptospira borgpetersenii serogroup Ballum. Each micturition was collected separately in metabolic cages, at 12 time points from 7 to 117 days post-infection (dpi). We detected Leptospira in all urine samples collected (up to 8 per time point per mouse) proving that Leptospira excretion is continuous with ca. 90% live L. borgpetersenii Ballum, revealed by viability quantitative polymerase chain reaction. Microscopic visualization by Live/Dead fluorescence confirmed this high proportion of live bacteria and demonstrated that L. borgpetersenii Ballum are excreted, at least partly, as bacterial aggregates. We observed two distinct phases in the excretion dynamics, first an increase in Leptospira concentration shed in the urine between 7 and 63 dpi followed by a plateau phase from 63 dpi onward, with up to 3 × 10 7 Leptospira per mL of urine. These two phases seem to correspond to progressive colonization of renal tubules first, then to stable cell survival and maintenance in kidneys. Therefore, chronically infected adult mice are able to contaminate the environment via urine at each micturition event throughout their lifetime. Because Leptospira excretion reached its maximum 2 months after infection, older rodents have a greater risk of contaminating their surrounding environment.

  13. Comparative study of dobutamine stress echocardiography and dual single-photon emission computed tomography (Thallium-201 and I-123 BMIPP) for assessing myocardial viability after acute myocardial infarction

    International Nuclear Information System (INIS)

    Yasugi, Naoko; Hiroki, Tadayuki

    2002-01-01

    Discordance between the 123 I-labelled 15-iodophenyl-3-R, S-methyl pentadecanoic acid (BMIPP) and 201 Tl findings may indicate myocardial viability (MV). This study compared dobutamine stress echocardiography (DSE) and single-photon emission computed tomography (SPECT) using the dual tracers for assessment of MV and prediction of functional recovery after acute myocardial infarction (AMI). DSE and dual SPECT were studied in 35 patients after AMI, of whom 28 underwent percutaneous coronary intervention in the acute stage. Dual SPECT was performed to compare the defect score of BMIPP and 201 Tl. The left ventricular wall motion score (WMS) was estimated during DSE and 6 months later to assess functional recovery of the infarct area. The rate of agreement of MV between dual SPECT and DSE was 89% (p 201 Tl were significantly smaller in patients with functional recovery than in those without. Assessment of MV using DSE concords with the results of dual SPECT in the early stage of AMI. DSE may have a higher predictive value for long-term functional recovery at the infarct area. However, a finding of positive MV by dual SPECT, without functional recovery, may indicate residual stenosis of the infarct-related artery, although the number of cases was small. Combined assessment by dual SPECT and DSE may be useful for detecting MV and jeopardized myocardium. Furthermore, the results suggest that functional recovery of dysfunctional myocardium may depend on the size of the infarct and risk area. (author)

  14. Bacterial morphologies in carbonaceous meteorites and comet dust

    OpenAIRE

    Wickramasinghe, N. Chandra; Wallis, Max K.; Gibson, Carl H.; Wallis, Jamie; Al-Mufti, Shirwan; Miyake, Nori

    2010-01-01

    Three decades ago the first convincing evidence of microbial fossils in carbonaceous chondrites was discovered and reported by Hans Dieter Pflug and his collaborators. In addition to morphology, other data, notably laser mass spectroscopy, confirmed the identification of such structures as putative bacterial fossils. Balloon-borne cryosampling of the stratosphere enables recovery of fragile cometary dust aggregates with their structure and carbonaceous matter largely intact. Scanning electron...

  15. Radiometric detection of bacterial metabolism

    International Nuclear Information System (INIS)

    Camargo, E.E.; Wagner Junior, H.N.

    1979-01-01

    The measurement of 14 CO 2 produced by the bacterial oxidation of labelled compounds is discussed as a means of evaluating the bacterial metabolism. The following items are discussed:automated radiometric detection, types of graphs, clinical applications of the radiometric system and influential factors. Complementary studies on bacterial assimilation of substances are presented. (M.A.) [pt

  16. Viability of microencapsulated bifidobacteria in set yogurt during refrigerated storage.

    Science.gov (United States)

    Adhikari, K; Mustapha, A; Grün, I U; Fernando, L

    2000-09-01

    Bifidobacteria are probiotic organisms that improve the microbial balance in the human gut. They can be incorporated as live cultures in fermented dairy foods, including yogurt, for transmission to humans. Because bifidobacteria are sensitive to high acidity, their viability in yogurt is limited. The objective of the present study was to investigate the effect of microencapsulation on the viability of bifidobacteria in yogurt during refrigerated storage for 30 d. Live bifidobacterial cells were encapsulated in kappa-carrageenan. Cell enumeration, determination of titratable acidity and pH, quantitation of lactic and acetic acids, and sensory evaluation (consumer test) were carried out on the yogurt samples. Microbiological results showed a decline of 78 and 70.5% in the population of Bifidobacterium longum B6 and B. longum ATCC 15708, respectively, for the treatments containing nonencapsulated cells. No difference in bifidobacterial population was observed in the encapsulated treatments. The acetic acid content in the yogurt with nonencapsulated bifidobacteria was higher than that in the plain yogurt (control) and encapsulated treatments. The increase in lactic acid content during storage was not different among the various treatments for B. longum B6, but was greater for nonencapsulated than encapsulated B. longum 15708 and the control. Consumers judged the nonencapsulated treatment as the most sour, which was likely due to the higher acetic acid content. Consumers preferred the control and nonencapsulated treatments over the encapsulated treatment. Microencapsulation appears to increase the viability of bifidobacteria in yogurt. This technique can be used to transmit bifidobacteria via fermented products provided that sensory characteristics of the product are improved or maintained.

  17. Cost Assessment Methodology and Economic Viability of Tidal Energy Projects

    Directory of Open Access Journals (Sweden)

    Eva Segura

    2017-11-01

    Full Text Available The exploitation of technologies with which to harness the energy from ocean currents will have considerable possibilities in the future thanks to their enormous potential for electricity production and their high predictability. In this respect, the development of methodologies for the economic viability of these technologies is fundamental to the attainment of a consistent quantification of their costs and the discovery of their economic viability, while simultaneously attracting investment in these technologies. This paper presents a methodology with which to determine the economic viability of tidal energy projects, which includes a technical study of the life-cycle costs into which the development of a tidal farm can be decomposed: concept and definition, design and development, manufacturing, installation, operation and maintenance and dismantling. These cost structures are additionally subdivided by considering their sub-costs and bearing in mind the main components of the tidal farm: the nacelle, the supporting tidal energy converter structure and the export power system. Furthermore, a technical study is developed in order to obtain an estimation of the annual energy produced (and, consequently, the incomes generated if the electric tariff is known by considering its principal attributes: the characteristics of the current, the ability of the device to capture energy and its ability to convert and export the energy. The methodology has been applied (together with a sensibility analysis to the particular case of a farm composed of first generation tidal energy converters in one of the Channel Island Races, the Alderney Race, in the U.K., and the results have been attained by means of the computation of engineering indexes, such as the net present value, the internal rate of return, the discounted payback period and the levelized cost of energy, which indicate that the proposed project is economically viable for all the case studies.

  18. Bacterial Cell Wall Components

    Science.gov (United States)

    Ginsberg, Cynthia; Brown, Stephanie; Walker, Suzanne

    Bacterial cell-surface polysaccharides cells are surrounded by a variety of cell-surface structures that allow them to thrive in extreme environments. Components of the cell envelope and extracellular matrix are responsible for providing the cells with structural support, mediating intercellular communication, allowing the cells to move or to adhere to surfaces, protecting the cells from attack by antibiotics or the immune system, and facilitating the uptake of nutrients. Some of the most important cell wall components are polysaccharide structures. This review discusses the occurrence, structure, function, and biosynthesis of the most prevalent bacterial cell surface polysaccharides: peptidoglycan, lipopolysaccharide, arabinogalactan, and lipoarabinomannan, and capsular and extracellular polysaccharides. The roles of these polysaccharides in medicine, both as drug targets and as therapeutic agents, are also described.

  19. Probing living bacterial adhesion by single cell force spectroscopy using atomic force microscopy

    DEFF Research Database (Denmark)

    Zeng, Guanghong; Ogaki, Ryosuke; Regina, Viduthalai R.

    be considered. We have therefore developed a simple and versatile method to make single-cell bacterial probes for measuring single cell adhesion with atomic force microscopy (AFM).[1] A single-cell probe was readily made by picking up a bacterial cell from a glass surface using a tipless AFM cantilever coated...... with a commercial cell adhesive CellTakTM. The method was applied to four different bacterial strains, and single-cell adhesion was measured on three surfaces (fresh glass, hydrophilic glass, mica). Attachment to the cantilever was stable during the 2 h of AFM force measurements, and viability was confirmed by Live....../Dead fluorescence staining at the end of each experiment. The adhesion force and final rupture length were dependent on bacterial strains, surfaces properties, and time of contact. The single-cell probe offers control of the cell immobilization, thus holds advantages over the commonly used multi-cell probes where...

  20. Obstacle recovery device

    International Nuclear Information System (INIS)

    Terai, Fujio; Furuya, Masaaki; Ugai, Masaru.

    1992-01-01

    The device of the present invention comprises a fiber scope for taking a recovery operation portion and an obstacle into a field of vision and photographing the state of the operation in the recovery operation portion and a display section for displaying the photographed image at a remote place. Concretely, the monitor of a remote operation section displays an image photographed by the fiber scope. A operation unit attached with a forceps and a fiber scope are brought closer, for example, to a fuel assembly in a reactor in the recovery operation portion. Then, the obstacle intruded into a minute space between fuels is recovered by the forceps while displaying state of the operation on the monitor of the remote operation section. Such a device certainly recover and remove a minute obstacle present in such a circumstance that a man's hand can not access, by the operation conducted under visual confirmation. (I.S.)

  1. Viability of Eggshells Ash Affecting the Setting Time of Cement

    OpenAIRE

    Fazeera Ujin; Kamran Shavarebi Ali; Zarina Yasmin Hanur Harith

    2016-01-01

    This research paper reports on the feasibility and viability of eggshells ash and its effects on the water content and setting time of cement. An experiment was carried out to determine the quantity of water required in order to follow standard cement paste of normal consistency in accordance with MS EN 196-3:2007. The eggshells ash passing the 90µm sieve was used in the investigation. Eggshells ash with percentage of 0%, 0.1%, 0.5%, 1.0%, 1.5% and 2.0% were constituted to replace the cement....

  2. Review of Vaccinia Virus and Baculovirus Viability Versus Virucides

    Science.gov (United States)

    2008-03-01

    pp 850- 853. Ignoffo, C.M.; Dutky, S.R. The Effect of Sodium Hypochlorite on the Viability and Infectivity of Bacillus and Beauveria Spores and...1977, 6, pp 411-415. Ignoffo, C.M.; Hostetter, D.L.; Pinnell, R.E. Stability of Baciluus thuringiensis and Baculovirus heliothis on Soybean Foliage...of Fecal or Respiratory Origin. http://www.iapmo.org/common/ pdf /lSS-Rome/Sobsey Environ Report.pdf. (Accessed 2003). 44 Stara, J.; Kocourek, F

  3. Bacterial meningitis in Nottingham.

    OpenAIRE

    Ispahani, P.

    1983-01-01

    Records of 171 cases of bacterial meningitis admitted to Nottingham hospitals from January 1974 to June 1980 were reviewed. The distribution of organisms producing meningitis and the factors influencing mortality in different age groups were assessed. Neisseria meningitidis, Haemophilus influenzae and Streptococcus pneumoniae accounted for 69% of all proven cases. The overall mortality was 26% being lowest in patients with meningococcal meningitis (0%) and highest in those with pneumococcal m...

  4. Analysis of bacterial communities and bacterial pathogens in a biogas plant by the combination of ethidium monoazide, PCR and Ion Torrent sequencing.

    Science.gov (United States)

    Luo, Gang; Angelidaki, Irini

    2014-09-01

    The present study investigated the changes of bacterial community composition including bacterial pathogens along a biogas plant, i.e. from the influent, to the biogas reactor and to the post-digester. The effects of post-digestion temperature and time on the changes of bacterial community composition and bacterial pathogens were also studied. Microbial analysis was made by Ion Torrent sequencing of the PCR amplicons from ethidium monoazide treated samples, and ethidium monoazide was used to cleave DNA from dead cells and exclude it from PCR amplification. Both similarity and taxonomic analysis showed that the bacterial community composition in the influent was changed after anaerobic digestion. Firmicutes were dominant in all the samples, while Proteobacteria decreased in the biogas reactor compared with the influent. Variations of bacterial community composition in the biogas reactor with time were also observed. This could be attributed to varying composition of the influent. Batch experiments showed that the methane recovery from the digested residues (obtained from biogas reactor) was mainly related with post-digestion temperature. However, post-digestion time rather than temperature had a significant effect on the changes of bacterial community composition. The changes of bacterial community composition were also reflected in the changes of relative abundance of bacterial pathogens. The richness and relative abundance of bacterial pathogens were reduced after anaerobic digestion in the biogas reactor. It was found in batch experiments that bacterial pathogens showed the highest relative abundance and richness after 30 days' post-digestion. Streptococcus bovis was found in all the samples. Our results showed that special attention should be paid to the post-digestion since the increase in relative abundance of bacterial pathogens after post-digestion might reflect regrowth of bacterial pathogens and limit biosolids disposal vectors. Copyright © 2014 Elsevier

  5. Recovery of personal neglect.

    Science.gov (United States)

    Iosa, Marco; Guariglia, Cecilia; Matano, Alessandro; Paolucci, Stefano; Pizzamiglio, Luigi

    2016-12-01

    Extrapersonal unilateral spatial neglect after stroke is associated to a poor rehabilitation outcome. Minor attention has been paid to the recovery of personal neglect, to its relationship with the recovery of extrapersonal neglect and of independency in activities of daily living. The present study aims at evaluating whether there is an association between recovery of extrapersonal and personal neglect. The secondary aim was to investigate if personal neglect may affect the effectiveness of neurorehabilitation in patients with subacute stroke. Observational study. Neurorehabilitation Hospital in Rome, Italy, inpatients. A sample of 49 patients with unilateral spatial neglect resulting from right ischemic cerebral infarction was enrolled in this study, divided into three subgroups according to the presence and the degree of personal neglect, and evaluated pre and postneurorehabilitation. Personal neglect was evaluated using Zoccolotti and Judica's Scale, extrapersonal neglect using Letter Cancellation Test, Barrage Test, Sentence Reading Test and Wundt-Jastrow Area Illusion Test. Barthel Index (BI), Rivermead Mobility Index, and Canadian Neurological Scale were also administered. Results showed the following: 1) recovery of personal neglect was not significantly correlated with that of extrapersonal neglect, despite both the disorders were ameliorated after a "non-specific" rehabilitation treatment; 2) personal neglect per se was not an additional negative prognostic factor in the rehabilitation findings. Our results suggested that the recoveries of the two types of neglect are independent from each other, and that the presence of personal neglect does not imply significant additional problems to the functional outcomes. Our study highlighted the need of novel tools to assess the presence and to improve the recovery of personal neglect.

  6. Neglected bacterial zoonoses.

    Science.gov (United States)

    Chikeka, I; Dumler, J S

    2015-05-01

    Bacterial zoonoses comprise a group of diseases in humans or animals acquired by direct contact with or by oral consumption of contaminated animal materials, or via arthropod vectors. Among neglected infections, bacterial zoonoses are among the most neglected given emerging data on incidence and prevalence as causes of acute febrile illness, even in areas where recognized neglected tropical diseases occur frequently. Although many other bacterial infections could also be considered in this neglected category, five distinct infections stand out because they are globally distributed, are acute febrile diseases, have high rates of morbidity and case fatality, and are reported as commonly as malaria, typhoid or dengue virus infections in carefully designed studies in which broad-spectrum diagnoses are actively sought. This review will focus attention on leptospirosis, relapsing fever borreliosis and rickettsioses, including scrub typhus, murine typhus and spotted fever group rickettsiosis. Of greatest interest is the lack of distinguishing clinical features among these infections when in humans, which confounds diagnosis where laboratory confirmation is lacking, and in regions where clinical diagnosis is often attributed to one of several perceived more common threats. As diseases such as malaria come under improved control, the real impact of these common and under-recognized infections will become evident, as will the requirement for the strategies and allocation of resources for their control. Copyright © 2015 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  7. Bacterial growth kinetics

    International Nuclear Information System (INIS)

    Boonkitticharoen, V.; Ehrhardt, J.C.; Kirchner, P.T.

    1989-01-01

    Quantitative measurement of bacterial growth may be made using a radioassay technique. This method measures, by scintillation counting, the 14 CO 2 derived from the bacterial metabolism of a 14 C-labeled substrate. Mathematical growth models may serve as reliable tools for estimation of the generation rate constant (or slope of the growth curve) and provide a basis for evaluating assay performance. Two models, i.e., exponential and logistic, are proposed. Both models yielded an accurate fit to the data from radioactive measurement of bacterial growth. The exponential model yielded high precision values of the generation rate constant, with an average relative standard deviation of 1.2%. Under most conditions the assay demonstrated no changes in the slopes of growth curves when the number of bacteria per inoculation was changed. However, the radiometric assay by scintillation method had a growth-inhibiting effect on a few strains of bacteria. The source of this problem was thought to be hypersensitivity to trace amounts of toluene remaining on the detector

  8. JLAB Hurricane recovery

    International Nuclear Information System (INIS)

    A. Hutton; D. Arenius; J. Benesch; S. Chattopadhyay; E. F. Daly; O. Garza; R. Kazimi; R. Lauzi; L. Merminga; W. Merz; R. Nelson; W. Oren; M. Poelker; P. Powers; J. Preble; V. Ganni; C. R. Reece; R. Rimmer; M. Spata; S. Suhring

    2004-01-01

    Hurricane Isabel, originally a Category 5 storm, arrived at Jefferson Lab on September 18, 2003 with winds of only 75 mph, creating little direct damage to the infrastructure. However, electric power was lost for four days allowing the superconducting cryomodules to warm up and causing a total loss of the liquid helium. The subsequent recovery of the cryomodules and the impact of the considerable amount of opportunistic preventive maintenance provides important lessons for all accelerator complexes, not only those with superconducting elements. The details of how the recovery process was structured and the resulting improvement in accelerator availability will be discussed in detail

  9. Ventilation with heat recovery

    DEFF Research Database (Denmark)

    Tommerup, Henrik M.; Svendsen, Svend

    2005-01-01

    This paper presents the experiences from the use of ventilation with heat recovery in several experimental single-family houses developed and built within the last four years to meet the new Danish energy requirements of 2005. Included are descriptions of the ventilation system components...... and the main functional demands as well as measurements of the thermal efficiency, electricity consumptions and building air tightness. The paper addresses the aspects of minimizing the heat loss from the duct system and the heat recovery unit (when placed in an unheated attic space) in order to obtain...

  10. Isolation of cell-free bacterial inclusion bodies.

    Science.gov (United States)

    Rodríguez-Carmona, Escarlata; Cano-Garrido, Olivia; Seras-Franzoso, Joaquin; Villaverde, Antonio; García-Fruitós, Elena

    2010-09-17

    Bacterial inclusion bodies are submicron protein clusters usually found in recombinant bacteria that have been traditionally considered as undesirable products from protein production processes. However, being fully biocompatible, they have been recently characterized as nanoparticulate inert materials useful as scaffolds for tissue engineering, with potentially wider applicability in biomedicine and material sciences. Current protocols for inclusion body isolation from Escherichia coli usually offer between 95 to 99% of protein recovery, what in practical terms, might imply extensive bacterial cell contamination, not compatible with the use of inclusion bodies in biological interfaces. Using an appropriate combination of chemical and mechanical cell disruption methods we have established a convenient procedure for the recovery of bacterial inclusion bodies with undetectable levels of viable cell contamination, below 10⁻¹ cfu/ml, keeping the particulate organization of these aggregates regarding size and protein folding features. The application of the developed protocol allows obtaining bacterial free inclusion bodies suitable for use in mammalian cell cultures and other biological interfaces.

  11. Bacterial Nanocellulose Magnetically Functionalized for Neuro-Endovascular Treatment.

    Science.gov (United States)

    Echeverry-Rendon, Mónica; Reece, Lisa M; Pastrana, Fernando; Arias, Sandra L; Shetty, Akshath R; Pavón, Juan Jose; Allain, Jean Paul

    2017-06-01

    Current treatments for brain aneurysms are invasive, traumatic, and not suitable in most patients with increased risks. A new alternative method is using scaffold stents to create a local and focal attraction force of cells for an in situ reconstruction of the tunica media. For this purpose, a nanostructured bioactive coating is designed to render an asymmetric region of the stent scaffold magnetic and biomimetic, which utilizes bacterial nanocellulose (BNC) as a platform for both magnetic and cell attraction as well as proliferation. The magnetization of the BNC is realized through the reaction of Fe III and II, precipitating superparamagnetic iron oxide nanoparticles (SPION). Subsequently, magnetic bacterial nanocellulose (MBNC) is coated with polyethylene glycol to improve its biocompatibility. Cytotoxicity and biocompatibility are evaluated using porcine aortic smooth muscle cells. Preliminary cellular migration assays demonstrate the behavior between MBNC and cells labeled with SPION. In this work, (1) synthesis of BNC impregnated with magnetic nanoparticles is successfully demonstrated; (2) a viable, resilient, and biocompatible hydrogel membrane is tested for neuroendovascular application using a stent scaffold; (3) cell viability and minimal cytotoxicity is achieved; (4) cell migration tests and examination of cellular magnetic attraction confirm the viability of MBNC as a multifunctional coating. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Probing living bacterial adhesion by single cell force spectroscopy using atomic force microscopy

    DEFF Research Database (Denmark)

    Zeng, Guanghong; Ogaki, Ryosuke; Regina, Viduthalai R.

    Bacteria initiate attachment to the surfaces with the aid of different extracellular polymers. To quantitatively study how these polymers mediate bacterial adhesion and possibly their interactions, it is essential to go down to single cell level, with in mind that cell-to-cell variation should...... with a commercial cell adhesive CellTakTM. The method was applied to four different bacterial strains, and single-cell adhesion was measured on three surfaces (fresh glass, hydrophilic glass, mica). Attachment to the cantilever was stable during the 2 h of AFM force measurements, and viability was confirmed by Live...

  13. Effects of copper supplement on growth and viability of strains used as starters and adjunct cultures for Emmental cheese manufacture.

    Science.gov (United States)

    Rodríguez, L Mato; Alatossava, T

    2008-10-01

    To determine the effects of supplemented copper (Cu2+) on growth and viability of strains used as starters and adjunct cultures for Emmental cheese manufacture. Thirteen strains belonging to Lactobacillus delbrueckii, Lactobacillus helveticus, Lactobacillus rhamnosus, Streptococcus thermophilus or Propionibacterium freudenreichii species were exposed to various copper concentrations in the proper growth medium at relevant growth temperatures, and the effects of supplemented copper on bacterial growth and cell viability were determined by optical density and pH measurements, also by platings. Among the species considered, L. delbrueckii was the most copper resistant and S. thermophilus the most sensitive to copper. Anaerobic conditions increased this sensitivity significantly. There was also a considerable amount of variation in copper resistance at strain level. Copper resistance is both a species- and strain-dependent property and may reflect variability in copper-binding capacities by cell wall components among species and strains. In addition, the chemical state of copper may be involved. This study revealed that copper resistance is a highly variable property among starter and adjunct strains, and this variability should be considered when strains are selected for Emmental cheese manufacture.

  14. A Spectrophotometric Assay for Robust Viability Testing of Seed Batches Using 2,3,5-Triphenyl Tetrazolium Chloride: Using Hordeum vulgare L. as a Model

    Directory of Open Access Journals (Sweden)

    Laura Lopez Del Egido

    2017-05-01

    Full Text Available A comparative analysis was carried out of published methods to assess seed viability using 2,3,5-triphenyltetrazolium chloride (TTC based assays of seed batches. The tests were carried out on seeds of barley (Hordeum vulgare cv. Optic as a model. We established that 10% [w/v] trichloroacetic acid (TCA/methanol is superior to the acetone and methanol-only based methods: allowing the highest recovery of formazan and the lowest background optical density (OD readings, across seed lots comprising different ratios of viable and dead seeds. The method allowed a linear-model to accurately capture the statistically significant relationship between the quantity of formazan that could be extracted using the method we developed and the seed temperature-response, and seed viability as a function of artificially aged seed lots. Other quality control steps are defined to help ensure the assay is robust and these are reported in a Standard Operating Procedure.

  15. Production and economic viability of feedlot beef cattle categories

    Directory of Open Access Journals (Sweden)

    Petrônio Batista dos Santos

    2017-04-01

    Full Text Available This study was realized to evaluate the production and economic viability of finished beef cattle in feedlot in the Cerrado biome of Piauí State, Brazil. One hundred and fifty cattle -50 bulls (B with an body weight of 283.0 ± 20.82 kg, at 30 months of age; and 100 cull cows (CC with an body weight of 296.1 ± 17.80 kg, at 100 months of age- were used in a completely randomized design. The animal performance indicators for the evaluation of economic viability were initial age (months, slaughter age (months, was initial body weight (kg, final body weight (kg, daily feed intake (kg animal-1; kg kg-1 BW, diet cost (R$ kg-1 of diet, cost of kg produced (R$ kg-1 produced, and average price of the kg of meat for finishing (R$. The CC consumed more sorghum silage and concentrate than B (p < 0.05.There was a difference between the categories (p < 0.05 for gross revenue, balance, opportunity cost, and net revenue per animal, with higher values found for the steer category. The animal category did not affect the profitability of the system, although the bulls provided lower revenues than cull cows.

  16. Resuscitation at the limits of viability--an Irish perspective.

    LENUS (Irish Health Repository)

    Khan, R A

    2012-02-01

    BACKGROUND: Advances in neonatal care continue to lower the limit of viability. Decision making in this grey zone remains a challenging process. OBJECTIVE: To explore the opinions of healthcare providers on resuscitation and outcome in the less than 28-week preterm newborn. DESIGN\\/METHODS: An anonymous postal questionnaire was sent to health care providers working in maternity units in the Republic of Ireland. Questions related to neonatal management of the extreme preterm infant, and estimated survival and long-term outcome. RESULTS: The response rate was 55% (74% obstetricians and 70% neonatologists). Less than 1% would advocate resuscitation at 22 weeks, 10% of health care providers advocate resuscitation at 23 weeks gestation, 80% of all health care providers would resuscitate at 24 weeks gestation. 20% of all health care providers would advocate cessation of resuscitation efforts on 22-25 weeks gestation at 5 min of age. 65% of Neonatologists and 54% trainees in Paediatrics would cease resuscitation at 10 min of age. Obstetricians were more pessimistic about survival and long term outcome in newborns delivered between 23 and 27 weeks when compared with neonatologists. This difference was also observed in trainees in paediatrics and obstetrics. CONCLUSION: Neonatologists, trainees in paediatrics and neonatal nurses are generally more optimistic about outcome than their counterparts in obstetrical care and this is reflected in a greater willingness to provide resuscitation efforts at the limits of viability.

  17. Improvement on The Ellis and Roberts Viability Model

    Directory of Open Access Journals (Sweden)

    Guoyan Zhou

    2016-05-01

    Full Text Available With data sets of germination percent and storage time of seed lot of wheat and sorghum stored at three different storage temperature(t, °C with three different water content (m, % of seeds, together with data set of buckwheat and lettuce reported in literatures, the possibility that seed survival curve were transformed into line by survival proportion and the relationship that logarithm of average viability period (logp50 and standard deviation of seed death distribution in time (δwith t, m and interaction between t and m were analysed. Result indicated that survival proportion transformed seed survival curve to line were much easier than the probability adopted by Ellis and Roberts, and the most important factor affecting logp50 and δ of seed lot was interaction between t and m. Thus, Ellis and Roberts viability model were suggested to be improved as Ki=Vi-p/10K-CWT (t×m to predict longevity of seed lot with initial germination percent unknown, a new model of Gi/G0=A-P/10K-CWT(t×m was constructed to predict longevity of seed lot with initial germination percent already known.

  18. Noninvasive diagnosis of seed viability using infrared thermography

    Science.gov (United States)

    Kranner, Ilse; Kastberger, Gerald; Hartbauer, Manfred; Pritchard, Hugh W.

    2010-01-01

    Recent advances in the noninvasive analyses of plant metabolism include stress imaging techniques, mainly developed for vegetative tissues. We explored if infrared thermography can be used to predict whether a quiescent seed will germinate or die upon water uptake. Thermal profiles of viable, aged, and dead Pisum sativum seeds were recorded, and image analysis of 22,000 images per individual seed showed that infrared thermography can detect imbibition- and germination-associated biophysical and biochemical changes. These “thermal fingerprints” vary with viability in this species and in Triticum aestivum and Brassica napus seeds. Thermogenesis of the small individual B. napus seeds was at the limit of the technology. We developed a computer model of “virtual pea seeds,” that uses Monte Carlo simulation, based on the heat production of major seed storage compounds to unravel physico-chemical processes of thermogenesis. The simulation suggests that the cooling that dominates the early thermal profiles results from the dissolution of low molecular-weight carbohydrates. Moreover, the kinetics of the production of such “cooling” compounds over the following 100 h is dependent on seed viability. We also developed a deterministic tool that predicts in the first 3 hours of water uptake, when seeds can be redried and stored again, whether or not a pea seed will germinate. We believe that the early separation of individual, ungerminated seeds (live, aged, or dead) before destructive germination assessment creates unique opportunities for integrative studies on cell death, differentiation, and development. PMID:20133712

  19. Cell viability and functionality of probiotic bacteria in dairy products

    Directory of Open Access Journals (Sweden)

    Gabriel eVinderola

    2011-05-01

    Full Text Available Probiotic bacteria, according to the definition adopted by the World Health Organization in 2002, are live microorganisms, which when administered in adequate amounts confer a health benefit to the host. Recent studies show that the same probiotic strain produced and/or preserved under different storage conditions, may present different responses regarding their susceptibility to the adverse conditions of the gastrointestinal tract, its capacity to adhere to the intestinal epithelium, or its immunomodulating capacity, being the functionality affected without changes in cell viability. This could imply that the control of cell viability is not always enough to guarantee the functionality (probiotic capacity of a strain. Therefore, a new challenge arises for food technologists and microbiologists when it comes to designing and monitoring probiotic food: to be able to monitor the cell functionality a probiotic microorganism along all the stages the strain goes through from the moment it is produced and included into the food vehicle until to the moment of consumption. Conventional methodological tools or others still to be developed must be used. The application of cell membrane functionality markers, the use of tests of resistence to intestinal barriers, the study of surface properties and the application of in vivo models comes together as complementary tools to assess the actual capacity of a probiotic into a specific food to exert functional effects regardless the number of viable cells present at the moment of consumption.

  20. A Review: The Probiotic Bacteria Viability under Different Conditions

    Directory of Open Access Journals (Sweden)

    Lavinia Florina CALINOIU

    2016-11-01

    Full Text Available This review summarized the current knowledge on probiotics and on the effects that different conditions have under this type of bacteria. The purpose of this review was to evaluate the survival rate/resistance or viability of different probiotic bacteria under several conditions, such as: processing, food composition, storage, freezing, thawing, refrigeration, temperature, oxygen, pH, gastrointestinal environment and package. Nowadays, the demand on probiotic functional foods is increasing rapidly, as the consumers became more aware about the potential health benefits, due to the fact that probiotics help in maintaining the balance and composition of intestinal flora and protect it from pathogens. A daily ingestion of 108–109 CFU ml−1 probiotic microorganisms is crucial in order to be able to demonstrate an effect in our organism, considering the dose and the effect of storage/gastrointestinal environments on the probiotic viability. Microencapsulation of probiotics in different polysaccharides was proven to be an ideal way to preserve and protect the cells from detrimental factors during processing, storage or resistance in the gastrointestinal transit, as many studies demonstrate it. There is a general interest in the improvement of the physical and mechanical stability of the polymers used in probiotics encapsulation, to ensure high population of probiotics not only in food during storage, but also after gastrointestinal digestion. Also, the carrier plays a very important role and should be carefully examined.

  1. Liquid-liquid extraction and liquid chromatography-mass spectrometry detection of curcuminoids from bacterial culture medium.

    Science.gov (United States)

    Tan, Suryani; Rupasinghe, Thusitha W T; Tull, Dedreia L; Augustin, Mary Ann; Gras, Sally L

    2015-04-15

    Liquid chromatography-mass spectrometry (LC-MS) has been used to detect polyphenolic curcuminoids found in turmeric but studies of metabolism by bacterial and mammalian cells in vitro are compromised by poor recovery from the culture medium. We report a liquid-liquid extraction procedure with ethyl acetate and use LC-MS to quantify extracted curcuminoids. Ethyl acetate allows recoveries of ∼ 80-86% of curcuminoids from the bacterial growth medium, bacterial cell lysate and combined bacterial cell and growth medium matrices; a clear improvement over acetonitrile where recoveries were ∼ 25-66%. This optimised method will enable studies of curcuminoid metabolism and may be applicable to other hydrophobic polyphenolic compounds. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Spectroscopy and viability of Bacillus subtilis spores after ultraviolet irradiation: implications for the detection of potential bacterial life on Europa.

    Science.gov (United States)

    Noell, Aaron C; Ely, Tucker; Bolser, Diana K; Darrach, Halley; Hodyss, Robert; Johnson, Paul V; Hein, Jeffrey D; Ponce, Adrian

    2015-01-01

    One of the most habitable environments in the Solar System outside of Earth may exist underneath the ice on Europa. In the near future, our best chance to look for chemical signatures of a habitable environment (or life itself) will likely be at the inhospitable icy surface. Therefore, it is important to understand the ability of organic signatures of life and life itself to persist under simulated europan surface conditions. Toward that end, this work examined the UV photolysis of Bacillus subtilis spores and their chemical marker dipicolinic acid (DPA) at temperatures and pressures relevant to Europa. In addition, inactivation curves for the spores at 100 K, 100 K covered in one micron of ice, and 298 K were measured to determine the probability for spore survival at the surface. Fourier transform infrared spectra of irradiated DPA showed a loss of carboxyl groups to CO2 as expected but unexpectedly showed significant opening of the heterocyclic ring, even for wavelengths>200 nm. Both DPA and B. subtilis spores showed identical unknown spectral bands of photoproducts after irradiation, further highlighting the importance of DPA in the photochemistry of spores. Spore survival was enhanced at 100 K by ∼5× relative to 298 K, but 99.9% of spores were still inactivated after the equivalent of ∼25 h of exposure on the europan surface.

  3. Effect of Ultraviolet Light Irradiation Combined with Riboflavin on Different Bacterial Pathogens from Ocular Surface Infection

    OpenAIRE

    Shen, Jing; Liang, Qingfeng; Su, Guanyu; Zhang, Yang; Wang, Zhiqun; Liang, Hong; Baudouin, Christophe; Labbé, Antoine

    2017-01-01

    In order to study Staphylococcus epidermis and Staphylococcus aureus in vitro viability after the exposure to ultraviolet (UV) light and riboflavin, twelve strains of Staphylococcus epidermis and twelve strains of Staphylococcus aureus were isolated from patients with bacterial keratitis. The growth situation of Staphylococcus epidermidis and Staphylococcus aureus under different experimental conditions was qualitatively observed. The number of colonies surviving bacteria was counted under di...

  4. Cost Recovery Through Depreciation.

    Science.gov (United States)

    Forrester, Robert T.; Wesolowski, Leonard V.

    1983-01-01

    The approach of adopting depreciation rather than use allowance in order to recover more accurately the cost of college buildings and equipment used on federal projects is considered. It is suggested that depreciation will offer most colleges and universities a higher annual recovery rate, and an opportunity for better facilities planning. For…

  5. Collegiate Recovery Programs

    Science.gov (United States)

    Harris, Kitty S.; Kimball, Thomas G.; Casiraghi, Ann M.; Maison, Sara J.

    2014-01-01

    More than ever, people are seeking substance use disorder treatment during the adolescent and young adult stages of development. Developmentally, many of these young adults new to recovery are in the process of making career decisions that may require attendance at a college or university. However, the collegiate environment is not conducive to a…

  6. Beyond enhanced recovery?

    DEFF Research Database (Denmark)

    Jørgensen, Christoffer C; Kehlet, Henrik

    2014-01-01

    We read with great interest the special article by Smart and Daniels discussing several important topics of perioperative care, especially regarding lack of consensus on the definition of "postoperative recovery", and need for further understanding of the pathogenic mechanisms. However, we disagree...

  7. The effects of storage conditions on the viability of ...

    African Journals Online (AJOL)

    SARAKA DANIEL

    2015-01-07

    Jan 7, 2015 ... and stirring for 3 min using vortex mixer (Sterilin ® STUART LTD). Thereafter, the fecal samples were centrifuged at 3000 rpm for ... Recovery of enteropathogenics bacteria stored in continuous cyclic frozen without thawing in the preservation media at -20°C. A1,Yersinia enterocolitica IP383. B1, Salmonella ...

  8. Atomic Layer Deposition of a Silver Nanolayer on Advanced Titanium Orthopedic Implants Inhibits Bacterial Colonization and Supports Vascularized de Novo Bone Ingrowth.

    Science.gov (United States)

    Devlin-Mullin, Aine; Todd, Naomi M; Golrokhi, Zahra; Geng, Hua; Konerding, Moritz A; Ternan, Nigel G; Hunt, John A; Potter, Richard J; Sutcliffe, Chris; Jones, Eric; Lee, Peter D; Mitchell, Christopher A

    2017-06-01

    Joint replacement surgery is associated with significant morbidity and mortality following infection with either methicillin-resistant Staphylococcus aureus (MRSA) or Staphylococcus epidermidis. These organisms have strong biofilm-forming capability in deep wounds and on prosthetic surfaces, with 10 3 -10 4 microbes resulting in clinically significant infections. To inhibit biofilm formation, we developed 3D titanium structures using selective laser melting and then coated them with a silver nanolayer using atomic layer deposition. On bare titanium scaffolds, S. epidermidis growth was slow but on silver-coated implants there were significant further reductions in both bacterial recovery (p titanium scaffolds and not further affected by silver coating. Ultrastructural examination and viability assays using either human bone or endothelial cells, demonstrated strong adherence and growth on titanium-only or silver-coated implants. Histological, X-ray computed microtomographic, and ultrastructural analyses revealed that silver-coated titanium scaffolds implanted into 2.5 mm defects in rat tibia promoted robust vascularization and conspicuous bone ingrowth. We conclude that nanolayer silver of titanium implants significantly reduces pathogenic biofilm formation in vitro, facilitates vascularization and osseointegration in vivo making this a promising technique for clinical orthopedic applications. © 2017 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. The feasibility of the initial postsystolic to systolic strain rate ratio as a predictor of the viability of ischemic myocardium with acute myocardial infarction.

    Science.gov (United States)

    Park, Soon Chang; Kang, Ki-Woon; Yoon, Hyeon Soo; Myung, Jin Cheol; Choi, Yu Jeong; Park, Sang Hyun; Jung, Kyung Tae; Chin, Jung Yeon

    2014-08-01

    Investigations of a strain index for the viability of ischemic myocardium with acute myocardial infarction (AMI) have been challenging. Therefore, the aim of this study was to evaluate patients with AMI to determine an optimal strain index for predicting the viability of ischemic myocardium. A total of 57 patients with AMI were assessed according to two-dimensional (2D) speckle tracking imaging strain and strain rate (SR), measured during the acute phase before urgent revascularization and at a 1-year follow-up postrevascularization. During the acute phase, all the myocardial segments were classified according to the acute end-systolic strain (Ses) values as normal (Ses ≤ -13%), hypocontractile (-13% -7%). At the 1-year follow-up, we reassessed the recovery of the segments with a severe contractile abnormality. The viability of these segments was defined as an improved Ses (≤ -7%) at follow-up postrevascularization. The Ses values, postsystolic strain index (PSI), and SR values were significantly better in the viable segments than in the nonviable segments at both the acute phase and at follow-up (P < 0.001). The initial postsystolic to systolic SR ratio (SRps/SRs) had the best area under the curve (AUC = 0.897). In addition, a cutoff value of 0.6 predicted recovery from a severe contractile abnormality with a sensitivity of 75% and a specificity of 88%. The initial SRps/SRs ratio identified the viability of ischemic myocardium with AMI; therefore, this novel index may be clinically useful in the treatment of patients with AMI. © 2013, Wiley Periodicals, Inc.

  10. Evaluation of bone viability in patients after girdlestone arthroplasty: comparison of bone SPECT/CT and MRI

    International Nuclear Information System (INIS)

    Diederichs, G.; Collettini, F.; Hamm, B.; Makowski, M.R.; Hoppe, P.; Brenner, W.; Wassilew, G.

    2017-01-01

    To test the diagnostic performance of bone SPECT/CT and MRI for the evaluation of bone viability in patients after girdlestone-arthroplasty with histopathology used as gold standard. In this cross-sectional study, patients after girdlestone-arthroplasty were imaged with single-photon-emission-computed-tomography/computed-tomography (SPECT/CT) bone-scans using 99mTc-DPD. Additionally, 1.5 T MRI was performed with turbo-inversion-recovery-magnitude (TIRM), contrast-enhanced T1-fat sat (FS) and T1-mapping. All imaging was performed within 24 h prior to revision total-hip-arthroplasty in patients with a girdlestone-arthroplasty. In each patient, four standardized bone-tissue-biopsies (14 patients) were taken intraoperatively at the remaining acetabulum superior/inferior and trochanter major/minor. Histopathological evaluation of bone samples regarding bone viability was used as gold standard. A total of 56 bone-segments were analysed and classified as vital (n = 39) or nonvital (n = 17) by histopathology. Mineral/late-phase SPECT/CT showed a high sensitivity (90%) and specificity (94%) to distinguish viable and nonviable bone tissue. TIRM (sensitivity 87%, specificity 88%) and contrast-enhanced T1-FS (sensitivity 90%, specificity 88%) also achieved a high sensitivity and specificity. T1-mapping achieved the lowest values (sensitivity 82%, specificity 82%). False positive results in SPECT/CT and MRI resulted from small bone fragments close to metal artefacts. Both bone SPECT/CT and MRI allow a reliable differentiation between viable and nonviable bone tissue in patients after girdlestone arthroplasty. The findings of this study could also be relevant for the evaluation of bone viability in the context of avascular bone necrosis. (orig.)

  11. Evaluation of bone viability in patients after girdlestone arthroplasty: comparison of bone SPECT/CT and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Diederichs, G.; Collettini, F.; Hamm, B.; Makowski, M.R. [Department of Radiology, Berlin (Germany); Hoppe, P.; Brenner, W. [Department of Nuclear Medicine, Berlin (Germany); Wassilew, G. [Department of Orthopedic Surgery, Berlin (Germany)

    2017-09-15

    To test the diagnostic performance of bone SPECT/CT and MRI for the evaluation of bone viability in patients after girdlestone-arthroplasty with histopathology used as gold standard. In this cross-sectional study, patients after girdlestone-arthroplasty were imaged with single-photon-emission-computed-tomography/computed-tomography (SPECT/CT) bone-scans using 99mTc-DPD. Additionally, 1.5 T MRI was performed with turbo-inversion-recovery-magnitude (TIRM), contrast-enhanced T1-fat sat (FS) and T1-mapping. All imaging was performed within 24 h prior to revision total-hip-arthroplasty in patients with a girdlestone-arthroplasty. In each patient, four standardized bone-tissue-biopsies (14 patients) were taken intraoperatively at the remaining acetabulum superior/inferior and trochanter major/minor. Histopathological evaluation of bone samples regarding bone viability was used as gold standard. A total of 56 bone-segments were analysed and classified as vital (n = 39) or nonvital (n = 17) by histopathology. Mineral/late-phase SPECT/CT showed a high sensitivity (90%) and specificity (94%) to distinguish viable and nonviable bone tissue. TIRM (sensitivity 87%, specificity 88%) and contrast-enhanced T1-FS (sensitivity 90%, specificity 88%) also achieved a high sensitivity and specificity. T1-mapping achieved the lowest values (sensitivity 82%, specificity 82%). False positive results in SPECT/CT and MRI resulted from small bone fragments close to metal artefacts. Both bone SPECT/CT and MRI allow a reliable differentiation between viable and nonviable bone tissue in patients after girdlestone arthroplasty. The findings of this study could also be relevant for the evaluation of bone viability in the context of avascular bone necrosis. (orig.)

  12. The Comparison of One and Two Steps Equilibration in Vitrification Process on The Morphology and Viability of Mouse Blastocysts

    Directory of Open Access Journals (Sweden)

    Ita Djuwita

    2010-09-01

    Full Text Available A study was conducted to compare the effect of one and two steps equilibration method of vitrificationon the morphology and viability of mouse blastocysts. Blastocysts were firstly exposed to modified PhosphateBuffered saline (mPBS containing 1% Bovine Serum Albumin (BSA proceeded by exposure in mPBSrespectively containing 0.25M sucrose (S for 2 minutes . Blastocysts were then exposed for 2 minutesrespectively to mPS+0.5M S (one step method or in mPBS+0.5M S+10% ethylene glycol (EG (two stepmethod.. Blastocysts were then exposed in mPBS+0.5M S+30% EG for 60 second, loaded into 0.25 mlplastic straw, and exposed immediately in vapor of liquid nitrogen for 10 second before they were and thenplunged into liquid nitrogen. The blastocysts were reconstituted by diluting with mPBS+0.5M S followedby mPBS+0.25M S for each 3 min and washed in mPBS without sucrose. The viability of cells was assessedby fluorescent vital staining, by re-expansion for 24 hours in vitro culture, and by implantation into therecipient oviduct. The percentages of morphologically normal blastocysts following recovery fromvitrification were higher (p<0.05 in one step equilibration than in those of two steps methods (89.6%. vs82.6%. The viability of blastocysts examined under light microscope after staining with biz-benzimidizepropidiumiodine and 24 hours in vitro culture in one step methods (64.0%; 57.8% were higher (p<0.05compared with two steps methods (40.0%; 35.6%, respectively. The implantation rate of vitrifiedblastocysts (23.1% was not significantly different to that of fresh blastocysts (33.4%. These resultsshowed that the one and two step equilibration methods are effective for vitrification and maintaining theviability of the mouse blastocysts.

  13. Most Probable Number Rapid Viability PCR Method to Detect Viable Spores of Bacillus anthracis in Swab Samples

    Energy Technology Data Exchange (ETDEWEB)

    Letant, S E; Kane, S R; Murphy, G A; Alfaro, T M; Hodges, L; Rose, L; Raber, E

    2008-05-30

    This note presents a comparison of Most-Probable-Number Rapid Viability (MPN-RV) PCR and traditional culture methods for the quantification of Bacillus anthracis Sterne spores in macrofoam swabs generated by the Centers for Disease Control and Prevention (CDC) for a multi-center validation study aimed at testing environmental swab processing methods for recovery, detection, and quantification of viable B. anthracis spores from surfaces. Results show that spore numbers provided by the MPN RV-PCR method were in statistical agreement with the CDC conventional culture method for all three levels of spores tested (10{sup 4}, 10{sup 2}, and 10 spores) even in the presence of dirt. In addition to detecting low levels of spores in environmental conditions, the MPN RV-PCR method is specific, and compatible with automated high-throughput sample processing and analysis protocols.

  14. Population Viability Analysis of the Endangered Roan Antelope in Ruma National Park, Kenya, and Implications for Management.

    Science.gov (United States)

    Kimanzi, Johnstone K

    2018-01-01

    Population viability analysis (PVA) was used to (1) establish causes of roan population decline for the past 30 years in Ruma National Park (RNP), the only park where wild roans remain in Kenya, and (2) predict the probability of roan persistence under existing and alternative management options. PVA was done using long-term data based on population dynamics, life history, climatic conditions, and expert knowledge. Poaching was identified as the main cause of roan decline in RNP. Several antipoaching and prioritized habitat management interventions to promote population recovery and sustainable conservation of roans are described. PVA predictions indicated that, without these interventions, the roan population cannot persist more than 3 decades. Furthermore, ensuring sustainable conservation of roans in RNP will boost tourism in Western Kenyan and thus alleviate poverty in this part of the country. Improved income from tourism will reduce the possible pressures from hunting and give greater incentives for local people to be actively engaged in roan conservation.

  15. Optically induced dielectropheresis sorting with automated medium exchange in an integrated optofluidic device resulting in higher cell viability.

    Science.gov (United States)

    Lee, Gwo-Bin; Wu, Huan-Chun; Yang, Po-Fu; Mai, John D

    2014-08-07

    We demonstrated the integration of a microfluidic device with an optically induced dielectrophoresis (ODEP) device such that the critical medium replacement process was performed automatically and the cells could be subsequently manipulated by using digitally projected optical images. ODEP has been demonstrated to generate sufficient forces for manipulating particles/cells by projecting a light pattern onto photoconductive materials which creates virtual electrodes. The production of the ODEP force usually requires a medium that has a suitable electrical conductivity and an appropriate dielectric constant. Therefore, a 0.2 M sucrose solution is commonly used. However, this requires a complicated medium replacement process before one is able to manipulate cells. Furthermore, the 0.2 M sucrose solution is not suitable for the long-term viability of cells. In comparison to conventional manual processes, our automated medium replacement process only took 25 minutes. Experimental data showed that there was up to a 96.2% recovery rate for the manipulated cells. More importantly, the survival rate of the cells was greatly enhanced due to this faster automated process. This newly developed microfluidic chip provided a promising platform for the rapid replacement of the cell medium and this was also the first time that an ODEP device was integrated with other active flow control components in a microfluidic device. By improving cell viability after cell manipulation, this design may contribute to the practical integration of ODEP modules into other lab-on-a-chip devices and biomedical applications in the future.

  16. Radiology of bacterial pneumonia

    Energy Technology Data Exchange (ETDEWEB)

    Vilar, Jose E-mail: vilar_jlu@gva.es; Domingo, Maria Luisa; Soto, Cristina; Cogollos, Jonathan

    2004-08-01

    Bacterial pneumonia is commonly encountered in clinical practice. Radiology plays a prominent role in the evaluation of pneumonia. Chest radiography is the most commonly used imaging tool in pneumonias due to its availability and excellent cost benefit ratio. CT should be used in unresolved cases or when complications of pneumonia are suspected. The main applications of radiology in pneumonia are oriented to detection, characterisation and follow-up, especially regarding complications. The classical classification of pneumonias into lobar and bronchial pneumonia has been abandoned for a more clinical classification. Thus, bacterial pneumonias are typified into three main groups: Community acquired pneumonia (CAD), Aspiration pneumonia and Nosocomial pneumonia (NP).The usual pattern of CAD is that of the previously called lobar pneumonia; an air-space consolidation limited to one lobe or segment. Nevertheless, the radiographic patterns of CAD may be variable and are often related to the causative agent. Aspiration pneumonia generally involves the lower lobes with bilateral multicentric opacities. Nosocomial Pneumonia (NP) occurs in hospitalised patients. The importance of NP is related to its high mortality and, thus, the need to obtain a prompt diagnosis. The role of imaging in NP is limited but decisive. The most valuable information is when the chest radiographs are negative and rule out pneumonia. The radiographic patterns of NP are very variable, most commonly showing diffuse multifocal involvement and pleural effusion. Imaging plays also an important role in the detection and evaluation of complications of bacterial pneumonias. In many of these cases, especially in hospitalised patients, chest CT must be obtained in order to better depict these associate findings.

  17. Radiology of bacterial pneumonia

    International Nuclear Information System (INIS)

    Vilar, Jose; Domingo, Maria Luisa; Soto, Cristina; Cogollos, Jonathan

    2004-01-01

    Bacterial pneumonia is commonly encountered in clinical practice. Radiology plays a prominent role in the evaluation of pneumonia. Chest radiography is the most commonly used imaging tool in pneumonias due to its availability and excellent cost benefit ratio. CT should be used in unresolved cases or when complications of pneumonia are suspected. The main applications of radiology in pneumonia are oriented to detection, characterisation and follow-up, especially regarding complications. The classical classification of pneumonias into lobar and bronchial pneumonia has been abandoned for a more clinical classification. Thus, bacterial pneumonias are typified into three main groups: Community acquired pneumonia (CAD), Aspiration pneumonia and Nosocomial pneumonia (NP).The usual pattern of CAD is that of the previously called lobar pneumonia; an air-space consolidation limited to one lobe or segment. Nevertheless, the radiographic patterns of CAD may be variable and are often related to the causative agent. Aspiration pneumonia generally involves the lower lobes with bilateral multicentric opacities. Nosocomial Pneumonia (NP) occurs in hospitalised patients. The importance of NP is related to its high mortality and, thus, the need to obtain a prompt diagnosis. The role of imaging in NP is limited but decisive. The most valuable information is when the chest radiographs are negative and rule out pneumonia. The radiographic patterns of NP are very variable, most commonly showing diffuse multifocal involvement and pleural effusion. Imaging plays also an important role in the detection and evaluation of complications of bacterial pneumonias. In many of these cases, especially in hospitalised patients, chest CT must be obtained in order to better depict these associate findings

  18. Backup and recovery of Oracle Database using Recovery Manager

    OpenAIRE

    Hubáček, Filip

    2009-01-01

    The bachelor's thesis discusses the implementation of backup and recovery of Oracle database using Recovery Manager. There are described individual backup types available in Oracle database environment and recovery types. Author introduces the benefits of using Recovery Manager, as the main backup tool in comparison to other methods of performing backup / restore.The reader is acquaint with the results of tests of the possible backup types. The tested features are speed of backup operation, t...

  19. Bacterial Degradation of Pesticides

    DEFF Research Database (Denmark)

    Knudsen, Berith Elkær

    This PhD project was carried out as part of the Microbial Remediation of Contaminated Soil and Water Resources (MIRESOWA) project, funded by the Danish Council for Strategic Research (grant number 2104-08-0012). The environment is contaminated with various xenobiotic compounds e.g. pesticides......D student, to construct fungal-bacterial consortia in order to potentially stimulate pesticide degradation thereby increasing the chance of successful bioaugmentation. The results of the project are reported in three article manuscripts, included in this thesis. In manuscript I, the mineralization of 2...

  20. Bacterial mitotic machineries

    DEFF Research Database (Denmark)

    Gerdes, Kenn; Møller-Jensen, Jakob; Ebersbach, Gitte

    2004-01-01

    Here, we review recent progress that yields fundamental new insight into the molecular mechanisms behind plasmid and chromosome segregation in prokaryotic cells. In particular, we describe how prokaryotic actin homologs form mitotic machineries that segregate DNA before cell division. Thus, the Par......M protein of plasmid R1 forms F actin-like filaments that separate and move plasmid DNA from mid-cell to the cell poles. Evidence from three different laboratories indicate that the morphogenetic MreB protein may be involved in segregation of the bacterial chromosome....

  1. Changes in bacterial meningitis.

    OpenAIRE

    Carter, P E; Barclay, S M; Galloway, W H; Cole, G F

    1990-01-01

    In 1964, one of us (WHG) undertook a retrospective study of bacterial meningitis in childhood in the north east of Scotland during the period 1946-61. We have recently carried out a similar review of cases occurring during 1971-86, to compare the incidence, mortality, and bacteriological patterns. During the earlier period 285 cases occurred, a total incidence of 16.9/100,000 children per year. In the later period 274 children were affected, an annual incidence of 17.8/100,000. The overall mo...

  2. Cytotoxicity and Effects on Cell Viability of Nickel Nanowires

    KAUST Repository

    Rodriguez, Jose E.

    2013-05-01

    Recently, magnetic nanoparticles are finding an increased use in biomedical applications and research. Nanobeads are widely used for cell separation, biosensing and cancer therapy, among others. Due to their properties, nanowires (NWs) are gaining ground for similar applications and, as with all biomaterials, their cytotoxicity is an important factor to be considered before conducting biological studies with them. In this work, the cytotoxic effects of nickel NWs (Ni NWs) were investigated in terms of cell viability and damage to the cellular membrane. Ni NWs with an average diameter of 30-34 nm were prepared by electrodeposition in nanoporous alumina templates. The templates were obtained by a two-step anodization process with oxalic acid on an aluminum substrate. Characterization of NWs was done using X-Ray diffraction (XRD) and energy dispersive X-Ray analysis (EDAX), whereas their morphology was observed with scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Cell viability studies were carried out on human colorectal carcinoma cells HCT 116 by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) cell proliferation colorimetric assay, whereas the lactate dehydrogenase (LDH) homogenous membrane fluorimetric assay was used to measure the degree of cell membrane rupture. The density of cell seeding was calculated to obtain a specific cell number and confluency before treatment with NWs. Optical readings of the cell-reduced MTT products were measured at 570 nm, whereas fluorescent LDH membrane leakage was recorded with an excitation wavelength of 525 nm and an emission wavelength of 580 - 640 nm. The effects of NW length, cell exposure time, as well as NW:cell ratio, were evaluated through both cytotoxic assays. The results show that cell viability due to Ni NWs is affected depending on both exposure time and NW number. On the other hand, membrane rupture and leakage was only significant at later exposure times. Both

  3. Recovery capital pathways: Modelling the components of recovery wellbeing.

    Science.gov (United States)

    Cano, Ivan; Best, David; Edwards, Michael; Lehman, John

    2017-12-01

    In recent years, there has been recognition that recovery is a journey that involves the growth of recovery capital. Thus, recovery capital has become a commonly used term in addiction treatment and research yet its operationalization and measurement has been limited. Due to these limitations, there is little understanding of long-term recovery pathways and their clinical application. We used the data of 546 participants from eight different recovery residences spread across Florida, USA. We calculated internal consistency for recovery capital and wellbeing, then assessed their factor structure via confirmatory factor analysis. The relationships between time, recovery barriers and strengths, wellbeing and recovery capital, as well as the moderating effect of gender, were estimated using structural equations modelling. The proposed model obtained an acceptable fit (χ 2 (141, N=546)=533.642, pwellbeing. Gender differences were observed. We tested the pathways to recovery for residents in the recovery housing population. Our results have implications not only for retention as a predictor of sustained recovery and wellbeing but also for the importance of meaningful activities in promoting recovery capital and wellbeing. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Introducing Recovery Style for Modeling and Analyzing System Recovery

    NARCIS (Netherlands)

    Sözer, Hasan; Tekinerdogan, B.; Kruchten, P.; Garlan, D.; Woods, E.

    An analysis of the existing approaches for representing architectural views reveals that they focus mainly on functional concerns and are limited when considering quality concerns. We introduce the recovery style for modeling the structure of the system related to the recovery concern. The recovery

  5. The effects of Brazilian propolis on etiological agents of mastitis and the viability of bovine mammary gland explants.

    Science.gov (United States)

    Fiordalisi, Samira A L; Honorato, Luciana A; Loiko, Márcia R; Avancini, César A M; Veleirinho, Maria B R; Filho, Luiz C P Machado; Kuhnen, Shirley

    2016-03-01

    The objective of this study was to evaluate in vitro the antimicrobial activity of Brazilian propolis from Urupema, São Joaquim, and Agua Doce (Santa Catarina State) and green propolis from Minas Gerais State, and the effects of propolis on bovine mammary gland explant viability. The propolis samples differed in flavonoid content and antioxidant activity. Green propolis showed the highest content of flavonoids, followed by the sample from São Joaquim. The propolis from Urupema showed the lowest flavonoid content along with the lowest antioxidant activity. The total phenolics were similar across all studied samples. Despite phytochemical differences, the propolis samples from Minas Gerais, São Joaquim, and Urupema presented the same level of antimicrobial activity against Staphylococcus aureus strains. The reduction in S. aureus growth was, on average, 1.5 and 4 log10 times at 200 and 500 μg/mL, respectively. At concentrations of 1,000 μg/mL, all propolis reduced bacterial growth to zero. On the other hand, when the propolis were tested against strains of Escherichia coli, the samples presented weak antimicrobial activity. Mammary explants were maintained in culture for 96h without a loss in viability, demonstrating the applicability of the model in evaluating the toxicity of propolis. The origin and chemical composition of the propolis had an effect on mammary explant viability. We encountered inhibitory concentrations of 272.4, 171.8, 63.85, and 13.26 μg/mL for the propolis from Água Doce, Urupema, São Joaquim, and Mina Gerais, respectively. A clear association between greater antimicrobial activity and toxicity for mammary explants was observed. Of all propolis tested, the Urupema sample was noteworthy, as it showed antimicrobial activity at less toxic concentrations than the other samples, reducing bacterial growth to an average of 9.3 × 10(2) cfu/mL after 6h of contact using 200 μg/mL of extract. The results demonstrate the potential for Brazilian

  6. Simulations of Microbial-Enhanced Oil Recovery: Adsorption and Filtration

    DEFF Research Database (Denmark)

    Nielsen, Sidsel Marie; Nesterov, Igor; Shapiro, Alexander

    2014-01-01

    is introduced to study the process efficiency: the dimensionless time at which average recovery between pure water injection and maximum surfactant effect is reached. This characteristic recovery period (CRP) was studied as a function of the different MEOR parameters such as bacterial activity, filtration......In the context of microbial-enhanced oil recovery (MEOR) with injection of surfactant-producing bacteria into the reservoir, different types of bacteria attachment and growth scenarios are studied using a 1D simulator. The irreversible bacteria attachment due to filtration similar to the deep bed...... filtration (DBF) is examined along with the commonly used reversible equilibrium adsorption (REA). The characteristics of the two models are highlighted. The options for bacteria growth are the uniform growth in both phases and growth of attached bacteria only. It is found that uniform growth scenario...

  7. Disaster Debris Recovery Database - Landfills

    Data.gov (United States)

    U.S. Environmental Protection Agency — The US EPA Disaster Debris Recovery Database (DDRD) promotes the proper recovery, recycling, and disposal of disaster debris for emergency responders at the federal,...

  8. Brine Recovery in Containment (BRIC)

    Data.gov (United States)

    National Aeronautics and Space Administration — The Brine Residual in Containment (BRIC) system is a technology that enables recovery of water from concentrated brine wastewater. Recovery of water from...

  9. Bacterial adhesion and growth on a polymer brush-coating.

    Science.gov (United States)

    Nejadnik, M Reza; van der Mei, Henny C; Norde, Willem; Busscher, Henk J

    2008-10-01

    Biomaterials-related infections pose serious problems in implant surgery, despite the development of non-adhesive coatings. Non-adhesive coatings, like polymer brush-coatings, have so far only been investigated with respect to preventing initial bacterial adhesion, but never with respect to effects on kinetics of bacterial growth. Here, we compare adhesion and 20 h growth of three bacterial strains (Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa) on pristine and brush-coated silicone rubber in a parallel plate flow chamber. Brush-coatings were made using a tri-block copolymer of polyethylene oxide (PEO) and polypropylene oxide (PPO). Brush-coatings prevented adhesion of staphylococci to below 5 x 10(5)cm(-2) after 30 min, which is a 10-fold reduction compared to pristine silicone rubber. Biofilms grew on both brush-coated and pristine silicone rubber, while the viability of biofilms on brush-coatings was higher than on pristine silicone rubber. However, biofilms on brush-coatings developed more slowly and detached almost fully by high fluid shear. Brush-coating remained non-adhesive after S. epidermidis biofilm formation and subsequent removal whereas a part of its functionality was lost after removal of S. aureus biofilms. Adhesion, growth and detachment of P. aeruginosa were not significantly different on brush-coatings as compared with pristine silicone rubber, although here too the viability of biofilms on brush-coatings was higher. We conclude that polymer brush-coatings strongly reduce initial adhesion of staphylococci and delay their biofilm growth. In addition, biofilms on brush-coatings are more viable and easily removed by the application of fluid shear.

  10. Primary Motor Neuron Culture to Promote Cellular Viability and Myelination.

    Science.gov (United States)

    Suh, Jun-Kyo Francis; Hyung, Sujin

    2018-01-01

    A culture system that can recapitulate myelination in vitro will not only help us to better understand the mechanism of myelination and demyelination but also identify possible therapeutic interventions for treating demyelinating diseases. Here, we introduce a simple and reproducible myelination culture system using mouse motor neurons (MNs) and Schwann cells (SCs). Dissociated motor neurons are plated on a feeder layer of SCs, which interact with and wrap around the axons of MNs as they differentiate in culture. In our MN-SC co-culture system, MNs survive over 3 weeks and extend long axons. Both viability and axon growth of MNs in the co-culture are markedly enhanced as compared to those of MN monocultures. Co-labeling of myelin basic proteins and neuronal cell microtubules reveals that SCs form myelin sheaths by wrapping around the axons of MNs.

  11. Reconstruction of boundary conditions from internal conditions using viability theory

    KAUST Repository

    Hofleitner, Aude

    2012-06-01

    This article presents a method for reconstructing downstream boundary conditions to a HamiltonJacobi partial differential equation for which initial and upstream boundary conditions are prescribed as piecewise affine functions and an internal condition is prescribed as an affine function. Based on viability theory, we reconstruct the downstream boundary condition such that the solution of the Hamilton-Jacobi equation with the prescribed initial and upstream conditions and reconstructed downstream boundary condition satisfies the internal value condition. This work has important applications for estimation in flow networks with unknown capacity reductions. It is applied to urban traffic, to reconstruct signal timings and temporary capacity reductions at intersections, using Lagrangian sensing such as GPS devices onboard vehicles.

  12. Viability report for the ByWater Lakes project

    Energy Technology Data Exchange (ETDEWEB)

    Lowry, Thomas Stephen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Klise, Geoffrey Taylor [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Passell, Howard David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Peplinski, William J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2013-10-01

    This report presents the results from the hydrological, ecological, and renewable energy assessments conducted by Sandia National Laboratories at the ByWater Lakes site in Espanola, New Mexico for ByWater Recreation LLC and Avanyu Energy Services through the New Mexico small business assistance (NMSBA) program. Sandia's role was to assess the viability and provide perspective for enhancing the site to take advantage of renewable energy resources, improve and sustain the natural systems, develop a profitable operation, and provide an asset for the local community. Integral to this work was the identification the pertinent data and data gaps as well as making general observations about the potential issues and concerns that may arise from further developing the site. This report is informational only with no consideration with regards to the business feasibility of the various options that ByWater and Avanyu may be pursuing.

  13. Omics as a window to view embryo viability.

    Science.gov (United States)

    Krisher, Rebecca L; Schoolcraft, William B; Katz-Jaffe, Mandy G

    2015-02-01

    The advent of advanced omics technologies and the application of these techniques to the analysis of extremely limited material have opened the door to the investigation of embryo physiology in a focused, in-depth approach never before possible. The application of noninvasive metabolomic and proteomic platforms to understanding embryo viability permits the characterization of individual embryos in culture. Initial clinical data have highlighted the promise of these technologies for the development of noninvasive embryo selection criteria. In this way, a complex view of embryo function can be compiled and related to embryo development, quality, and outcome. Application of knowledge gained from omics will transform both our understanding of embryo physiology as well as our ability to select viable embryos for transfer in assisted reproductive technology. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  14. Cosmological viability of theories with massive spin-2 fields

    Energy Technology Data Exchange (ETDEWEB)

    Koennig, Frank

    2017-03-30

    Theories of spin-2 fields take on a particular role in modern physics. They do not only describe the mediation of gravity, the only theory of fundamental interactions of which no quantum field theoretical description exists, it furthermore was thought that they necessarily predict massless gauge bosons. Just recently, a consistent theory of a massive graviton was constructed and, subsequently, generalized to a bimetric theory of two interacting spin-2 fields. This thesis studies both the viability and consequences at cosmological scales in massive gravity as well as bimetric theories. We show that all consistent models that are free of gradient and ghost instabilities behave like the cosmological standard model, LCDM. In addition, we construct a new theory of massive gravity which is stable at both classical background and quantum level, even though it suffers from the Boulware-Deser ghost.

  15. Using field data to quantify chemical impacts on wildlife population viability.

    Science.gov (United States)

    Hilbers, Jelle P; Hoondert, Renske P J; Schipper, Aafke M; Huijbregts, Mark A J

    2018-01-16

    Environmental pollution is an important driver of biodiversity loss. Yet, to date, the effects of chemical exposure on wildlife populations have been quantified for only a few species, mainly due to a lack of appropriate laboratory data to quantify chemical impacts on vital rates. In this study we developed a method to quantify the effects of toxicant exposure on wildlife population persistence based on field monitoring data. We established field-based vital rate-response functions for toxicants, using quantile regression to correct for the influences of confounding factors on the vital rates observed, and combined the response curves with population viability modelling. We then applied the method to quantify the impact of DDE on three bird species: the white-tailed eagle, bald eagle and osprey. Population viability was expressed via five population extinction vulnerability metrics: population growth rate (r 1 ), critical patch size (CPS), minimum viable population size (MVP), probability of population extirpation (PE) and median time to population extirpation (MTE). We found that past DDE exposure concentrations increased population extirpation vulnerabilities of all three bird species. For example, at DDE concentrations of 25 mg/kg ww egg (the maximum historic exposure concentration reported in literature for the osprey), r 1 became small (white-tailed eagle and osprey) or close to zero (bald eagle), the CPS increased up to almost the size of Connecticut (white-tailed eagle and osprey) or West Virginia (bald eagle), the MVP increased up to approximately 90 (white-tailed eagle and osprey) or 180 breeding pairs (bald eagle), the PE increased up to almost certain extirpation (bald eagle) or only slightly elevated levels (white-tailed eagle and osprey) and the MTE became within decades (bald eagle) or remained longer than a millennium (white-tailed eagle and osprey). Our study provides a method to derive species-specific field-based response curves of toxicant

  16. Dependency of cerebral blood flow upon mean arterial pressure in patients with acute bacterial meningitis

    DEFF Research Database (Denmark)

    Møller, Kirsten; Larsen, Fin Stolze; Qvist, Jesper

    2000-01-01

    OBJECTIVE: Patients with acute bacterial meningitis are often treated with sympathomimetics to maintain an adequate mean arterial pressure (MAP). We studied the influence of such therapy on cerebral blood flow (CBF). DESIGN: Prospective physiologic trial. SETTING: The Department of Infectious...... Diseases, Copenhagen University Hospital, Denmark. PATIENTS: Sixteen adult patients with acute bacterial meningitis. INTERVENTION: Infusion of norepinephrine to increase MAP. MEASUREMENTS: During a rise in MAP induced by norepinephrine infusion, we measured relative changes in CBF by transcranial Doppler...... bacterial meningitis, CBF autoregulation is impaired. With recovery from meningitis, the cerebral vasculature regains the ability to maintain cerebral perfusion at a constant level despite variations in MAP....

  17. Energy Recovery Linacs

    CERN Document Server

    Merminga, L

    2005-01-01

    Successfully operating, pioneering Energy Recovery Linac (ERL) – based Free Electron Lasers (FELs) have paved the way towards powerful and highly efficient accelerators based on the principle of energy recovery. Pursued and envisioned ERL applications worldwide include high brilliance light sources for the production of both spontaneous and FEL radiation, high-energy electron cooling devices, and electron-ion colliders. The required electron source parameters, average beam current and beam energy of the proposed applications are a significant extrapolation from demonstrated performance. We present an overview of the accelerator physics and technology challenges encountered in the design of the various ERL projects around the world, as well as progress and development plans to achieving the required performance.

  18. Recovery in aluminium

    DEFF Research Database (Denmark)

    Gundlach, Carsten

    2006-01-01

    In the present thesis the development of a unique experimental method for volume characterisation of individual embedded crystallites down to a radius of 150 nm is presented. This method is applied to in-situ studies of recovery in aluminium. The method is an extension of 3DXRD microscopy, an X...... by the combined use of X-ray micro focusing optics, new scanning algorithms and the use of foils. The ratio of foil thickness to crystallite size should be at least 10 such that the central ones are situated in a bulk environment. To avoid thermal drifts, gold reference markers are deposited onto the sample...... are represented as strings. To identify the strings a combination of a 5D connected component type algorithm and multi-peak fitting was found to be superior. The first use of the method was a study of recovery of a deformed aluminium alloy (AA1050). The aluminium alloy was deformed by cold rolling to a thickness...

  19. Illness management and recovery

    DEFF Research Database (Denmark)

    Dalum, Helle Stentoft; Waldemar, Anna Kristine; Korsbek, Lisa

    2018-01-01

    OBJECTIVE: Illness Management and Recovery (IMR) is a psychosocial intervention with a recovery-oriented approach. The program has been evaluated in different settings; however evidence for the effects of IMR is still deficient. The aim of this trial was to investigate the benefits and harms...... of the IMR program compared with treatment as usual in Danish patients with schizophrenia or bipolar disorder. METHOD: The trial was designed as a randomized, assessor-blinded, multi-center, clinical trial investigating the IMR program compared with usual treatment. 198 people diagnosed with schizophrenia...... or service utilization. CONCLUSION: This randomized trial contributes to the evidence base of IMR by providing a methodological solid base for its conclusions; however the trial has some important limitations. More research is needed to get a firm answer on the effectiveness of the IMR....

  20. Exchange of rotor components in functioning bacterial flagellar motor

    International Nuclear Information System (INIS)

    Fukuoka, Hajime; Inoue, Yuichi; Terasawa, Shun; Takahashi, Hiroto; Ishijima, Akihiko

    2010-01-01

    The bacterial flagellar motor is a rotary motor driven by the electrochemical potential of a coupling ion. The interaction between a rotor and stator units is thought to generate torque. The overall structure of flagellar motor has been thought to be static, however, it was recently proved that stators are exchanged in a rotating motor. Understanding the dynamics of rotor components in functioning motor is important for the clarifying of working mechanism of bacterial flagellar motor. In this study, we focused on the dynamics and the turnover of rotor components in a functioning flagellar motor. Expression systems for GFP-FliN, FliM-GFP, and GFP-FliG were constructed, and each GFP-fusion was functionally incorporated into the flagellar motor. To investigate whether the rotor components are exchanged in a rotating motor, we performed fluorescence recovery after photobleaching experiments using total internal reflection fluorescence microscopy. After photobleaching, in a tethered cell producing GFP-FliN or FliM-GFP, the recovery of fluorescence at the rotational center was observed. However, in a cell producing GFP-FliG, no recovery of fluorescence was observed. The transition phase of fluorescence intensity after full or partially photobleaching allowed the turnover of FliN subunits to be calculated as 0.0007 s -1 , meaning that FliN would be exchanged in tens of minutes. These novel findings indicate that a bacterial flagellar motor is not a static structure even in functioning state. This is the first report for the exchange of rotor components in a functioning bacterial flagellar motor.

  1. Comparison of the cytotoxic effect of polystyrene latex nanoparticles on planktonic cells and bacterial biofilms

    International Nuclear Information System (INIS)

    Nomura, Toshiyuki; Fujisawa, Eri; Itoh, Shikibu; Konishi, Yasuhiro

    2016-01-01

    The cytotoxic effect of positively charged polystyrene latex nanoparticles (PSL NPs) was compared between planktonic bacterial cells and bacterial biofilms using confocal laser scanning microscopy, atomic force microscopy, and a colony counting method. Pseudomonas fluorescens, which is commonly used in biofilm studies, was employed as the model bacteria. We found that the negatively charged bacterial surface of the planktonic cells was almost completely covered with positively charged PSL NPs, leading to cell death, as indicated by the NP concentration being greater than that required to achieve single layer coverage. In addition, the relationship between surface coverage and cell viability of P. fluorescens cells correlated well with the findings in other bacterial cells (Escherichia coli and Lactococcuslactis). However, most of the bacterial cells that formed the biofilm were viable despite the positively charged PSL NPs being highly toxic to planktonic bacterial cells. This indicated that bacterial cells embedded in the biofilm were protected by self-produced extracellular polymeric substances (EPS) that provide resistance to antibacterial agents. In conclusion, mature biofilms covered with EPS exhibit resistance to NP toxicity as well as antibacterial agents.

  2. Comparison of the cytotoxic effect of polystyrene latex nanoparticles on planktonic cells and bacterial biofilms

    Energy Technology Data Exchange (ETDEWEB)

    Nomura, Toshiyuki, E-mail: nomura@chemeng.osakafu-u.ac.jp; Fujisawa, Eri; Itoh, Shikibu; Konishi, Yasuhiro [Osaka Prefecture University, Department of Chemical Engineering (Japan)

    2016-06-15

    The cytotoxic effect of positively charged polystyrene latex nanoparticles (PSL NPs) was compared between planktonic bacterial cells and bacterial biofilms using confocal laser scanning microscopy, atomic force microscopy, and a colony counting method. Pseudomonas fluorescens, which is commonly used in biofilm studies, was employed as the model bacteria. We found that the negatively charged bacterial surface of the planktonic cells was almost completely covered with positively charged PSL NPs, leading to cell death, as indicated by the NP concentration being greater than that required to achieve single layer coverage. In addition, the relationship between surface coverage and cell viability of P. fluorescens cells correlated well with the findings in other bacterial cells (Escherichia coli and Lactococcuslactis). However, most of the bacterial cells that formed the biofilm were viable despite the positively charged PSL NPs being highly toxic to planktonic bacterial cells. This indicated that bacterial cells embedded in the biofilm were protected by self-produced extracellular polymeric substances (EPS) that provide resistance to antibacterial agents. In conclusion, mature biofilms covered with EPS exhibit resistance to NP toxicity as well as antibacterial agents.

  3. Comparison of the cytotoxic effect of polystyrene latex nanoparticles on planktonic cells and bacterial biofilms

    Science.gov (United States)

    Nomura, Toshiyuki; Fujisawa, Eri; Itoh, Shikibu; Konishi, Yasuhiro

    2016-06-01

    The cytotoxic effect of positively charged polystyrene latex nanoparticles (PSL NPs) was compared between planktonic bacterial cells and bacterial biofilms using confocal laser scanning microscopy, atomic force microscopy, and a colony counting method. Pseudomonas fluorescens, which is commonly used in biofilm studies, was employed as the model bacteria. We found that the negatively charged bacterial surface of the planktonic cells was almost completely covered with positively charged PSL NPs, leading to cell death, as indicated by the NP concentration being greater than that required to achieve single layer coverage. In addition, the relationship between surface coverage and cell viability of P. fluorescens cells correlated well with the findings in other bacterial cells ( Escherichia coli and Lactococcus lactis). However, most of the bacterial cells that formed the biofilm were viable despite the positively charged PSL NPs being highly toxic to planktonic bacterial cells. This indicated that bacterial cells embedded in the biofilm were protected by self-produced extracellular polymeric substances (EPS) that provide resistance to antibacterial agents. In conclusion, mature biofilms covered with EPS exhibit resistance to NP toxicity as well as antibacterial agents.

  4. Animal Models of Bacterial Keratitis

    Science.gov (United States)

    Marquart, Mary E.

    2011-01-01

    Bacterial keratitis is a disease of the cornea characterized by pain, redness, inflammation, and opacity. Common causes of this disease are Pseudomonas aeruginosa and Staphylococcus aureus. Animal models of keratitis have been used to elucidate both the bacterial factors and the host inflammatory response involved in the disease. Reviewed herein are animal models of bacterial keratitis and some of the key findings in the last several decades. PMID:21274270

  5. Changes in viability of two Antarctic marine bacteria exposed to solar radiation in the water column: influence of vertical mixing

    International Nuclear Information System (INIS)

    Hernandez, E.A.

    2007-01-01

    The effect of UV radiation on two Antarctic marine bacterial strains (UVps and UVvi) was studied in the water column of Potter Cove (South Shetland, Antarctica). Quartz flasks were filled with the bacterial suspensions and exposed to solar radiation at 0 m, 1 m and 3 m depth. Assays using flasks exposed to direct solar radiation and others using flasks covered with/by interferential filters which discriminate between UVA and UVB, were performed. In other assays, a vertical mixing of 4 m/h was simulated. Both strains showed a significant decrease in viability (expressed as colony - forming units) when exposed to a surface UVB dose of 8.4 kJ m -2 . Studies with interferential filters showed a significant decrease at 0 and 1 m depth under both UV treatments. The UVps strain appeared to be more sensitive to UVB than to UVA. Damage produced by UVB was attenuated by the vertical mixing when the surface UVB dose was 4.8 kJ m -2 . This effect was not observed when surface UVB dose was 7.7 kJ m -2 . These results show that the negative effect caused by UVB radiation on the bacterio plankton would be significant only in the first meter of water column of the Antarctic coastal waters with high levels of suspended particulate material. (author) [es

  6. Optimization of synbiotic yogurts with yacon pulp (Smallanthus sonchifolius and assessment of the viability of lactic acid bacteria

    Directory of Open Access Journals (Sweden)

    Vivianne Montarroyos PADILHA

    Full Text Available Abstract The aim of this study was check the effects of sugar, yacon pulp and skimmed milk powder in the aroma, flavour, texture, appearance, overall impression and intent to purchase on synbiotic yogurts to optimize the formulation using Response Surface Methodology. The most accepted formulations were subjected to viability tests during 21 days by counting traditional and probiotic bacteria. Were constructed a complete 23 factorial design, totalling 17 experiments, and considered independent variables (percentage of ingredients and dependent variables (sensory attributes. All attributes were graded using an acceptability assessment, for this balanced incomplete block was applied. The number of viable cells was determined using specific culture medium for each species. The percentage of yacon pulp had a pronounced negative influence on flavour, texture, appearance, overall impression and intent to purchase. Model predictions adjusted to the variables aroma, flavour, texture, appearance, overall impression and intent to purchase exhibited good predictive ability and hence could be used as tools for process control. Traditional bacterial strains and probiotic remained viable throughout the storage period. The counts of probiotic bacterial in the formulations were above 6 log CFU/g. The addition of Lactobacillus paracasei ssp. paracasei LBC 81 and yacon pulp to yogurt increased product acceptability.

  7. Role of viability of probiotic strains in their persistence in the gut and in mucosal immune stimulation.

    Science.gov (United States)

    Galdeano, C Maldonado; Perdigón, G

    2004-01-01

    To determine how probiotic bacteria contact with intestinal epithelial and immune cells and the conditions to induce a good mucosal immune stimulation. Lactobacillus casei was studied by transmission electron microscopy (TEM) to determine its interaction with the gut. We compared the influence of viable and nonviable lactic acid bacteria on the intestinal mucosal immune system (IMIS) and their persistence in the gut of mice. TEM showed whole Lact. casei adhered to the villi; the bacterial antigen was found in the cytoplasm of the enterocytes. Viable bacteria stimulated the IMIS to a greater extent than nonviable bacteria with the exception of Lact. delbrueckii subsp. bulgaricus. For all the strains assayed at 72 h no antigenic particles were found in the intestine. Antigenic particles but not the whole bacteria can enter to epithelial cells and contact with the immune cells. Bacterial viability is a condition for a better stimulation of the IMIS. We demonstrated that only antigenic particle interact with the immune cells and their fast clearance from the gut agrees with those described for the particulate antigens. The regular consumption of probiotics should not adversely affect the host.

  8. Recovery of uranium values

    International Nuclear Information System (INIS)

    Rowden, G.A.

    1982-01-01

    A process is provided for the recovery of uranium from an organic extractant phase containing an amine. The extractant phase is contacted in a number of mixing stages with an acidic aqueous stripping phase containing sulphate ions, and the phases are passed together through a series of mixing stages while maintaining a dispersion of droplets of one phase in the other. Uranium is precipitated from the final stage by raising the pH. An apparatus having several mixing chambers is described

  9. Sludge recovery apparatus

    International Nuclear Information System (INIS)

    Marmo, A.R.

    1979-01-01

    An improved design of a sludge recovery apparatus used in the fabrication of nuclear fuel is described. This apparatus provides for automatic separation of sludge from the grinder coolant, drying of the sludge into a flowable powder and transfer of the dry powder to a salvage container. It can be constructed to comply with criticality-safe-geometry requirements and to obviate need for operating personnel in its immediate vicinity. (UK)

  10. Recovery From Comorbidity

    Directory of Open Access Journals (Sweden)

    Mathew Carter

    2013-11-01

    Full Text Available Comorbidity among mood, anxiety, and alcohol disorders is common and burdensome, affecting individuals, families, and public health. A systematic and integrative review of the literature across disciplines and research methodologies was performed. Supradisciplinary approaches were applied to the review and the ensuing critical appraisal. Definitions, measurement, and estimation are controversial and inconstant. Recovery from comorbidity cannot be easily extricated from a sociocultural milieu. Methodological challenges in quantitative and qualitative research and across disciplines are many and are discussed. The evidence supporting current treatments is sparse and short-term, and modalities operating in isolation typically fail. People easily fall into the cracks between mental health and addiction services. Clinicians feel untrained and consumers bear the brunt of this: Judgmental and moralistic interactions persist and comorbidity is unrecognized in high-risk populations. Competing historical paradigms of mental illness and addiction present a barrier to progress and reductionism is an impediment to care and an obstacle to the integration and interpretation of research. What matters to consumers is challenging to quantify but worth considering: Finding employment, safe housing, and meaning are crucial to recovery. Complex social networks and peer support in recovery are important but poorly understood. The focus on modalities of limited evidence or generalizability persists in literature and practice. We need to consider different combinations of comorbidity, transitions as opposed to dichotomies of use or illness, and explore the long-term view and emic perspectives.

  11. Evaluating miscible flood projects for acquisition or viability

    International Nuclear Information System (INIS)

    Cassinat, J.C.

    1991-01-01

    Very little information exists regarding evaluating enhanced oil recovery (EOR) projects, in particular miscible floods. Due to the size and scope of most tertiary recovery projects, standard evaluation rules and techniques are too general and vague to adequately model these schemes. A procedure for identifying the risks associated with miscible EOR projects is presented. It is essential to set up a cash flow model that accurately represents the future performance of a miscible flood. Included in the model are the timing of crucial events such as expected solvent breakthrough and the injection of trace gas. The cash flow analysis allows a quick audit procedure and converts production into a monetary or economic evaluation criteria that can easily be compared to other investment alternatives. When evaluating a miscible flood project, forecasting production, solvent and chase gas recovery costs can become quite complex. An organized procedure for an evaluation will ensure that a comprehensive and thorough examination of all the data is completed, and will increase confidence levels associated with decision making. 32 refs., 4 figs., 4 tabs

  12. Platinum Recovery from Synthetic Extreme Environments by Halophilic Bacteria.

    Science.gov (United States)

    Maes, Synthia; Props, Ruben; Fitts, Jeffrey P; Smet, Rebecca De; Vilchez-Vargas, Ramiro; Vital, Marius; Pieper, Dietmar H; Vanhaecke, Frank; Boon, Nico; Hennebel, Tom

    2016-03-01

    Metal recycling based on urban mining needs to be established to tackle the increasing supply risk of critical metals such as platinum. Presently, efficient strategies are missing for the recovery of platinum from diluted industrial process streams, often characterized by extremely low pHs and high salt concentrations. In this research, halophilic mixed cultures were employed for the biological recovery of platinum (Pt). Halophilic bacteria were enriched from Artemia cysts, living in salt lakes, in different salt matrices (sea salt mixture and NH4Cl; 20-210 g L(-1) salts) and at low to neutral pH (pH 3-7). The main taxonomic families present in the halophilic cultures were Halomonadaceae, Bacillaceae, and Idiomarinaceae. The halophilic cultures were able to recover >98% Pt(II) and >97% Pt(IV) at pH 2 within 3-21 h (4-453 mg Ptrecovered h(-1) g(-1) biomass). X-ray absorption spectroscopy confirmed the reduction to Pt(0) and transmission electron microscopy revealed both intra- and extracellular Pt precipitates, with median diameters of 9-30 nm and 11-13 nm, for Pt(II) and Pt(IV), respectively. Flow cytometric membrane integrity staining demonstrated the preservation of cell viability during platinum recovery. This study demonstrates the Pt recovery potential of halophilic mixed cultures in acidic saline conditions.

  13. Role of (p)ppGpp in Viability and Biofilm Formation of Actinobacillus pleuropneumoniae S8.

    Science.gov (United States)

    Li, Gang; Xie, Fang; Zhang, Yanhe; Bossé, Janine T; Langford, Paul R; Wang, Chunlai

    2015-01-01

    Actinobacillus pleuropneumoniae is a Gram-negative bacterium and the cause of porcine pleuropneumonia. When the bacterium encounters nutritional starvation, the relA-dependent (p)ppGpp-mediated stringent response is activated. The modified nucleotides guanosine 5'-diphosphate 3'-diphosphate (ppGpp) and guanosine 5'-triphosphate 3'-diphosphate (pppGpp) are known to be signaling molecules in other prokaryotes. Here, to investigate the role of (p)ppGpp in A. pleuropneumoniae, we created a mutant A. pleuropneumoniae strain, S8ΔrelA, which lacks the (p)ppGpp-synthesizing enzyme RelA, and investigated its phenotype in vitro. S8ΔrelA did not survive after stationary phase (starvation condition) and grew exclusively as non-extended cells. Compared to the wild-type (WT) strain, the S8ΔrelA mutant had an increased ability to form a biofilm. Transcriptional profiles of early stationary phase cultures revealed that a total of 405 bacterial genes were differentially expressed (including 380 up-regulated and 25 down-regulated genes) in S8ΔrelA as compared with the WT strain. Most of the up-regulated genes are involved in ribosomal structure and biogenesis, amino acid transport and metabolism, translation cell wall/membrane/envelope biogenesis. The data indicate that (p)ppGpp coordinates the growth, viability, morphology, biofilm formation and metabolic ability of A. pleuropneumoniae in starvation conditions. Furthermore, S8ΔrelA could not use certain sugars nor produce urease which has been associated with the virulence of A. pleuropneumoniae, suggesting that (p)ppGpp may directly or indirectly affect the pathogenesis of A. pleuropneumoniae during the infection process. In summary, (p)ppGpp signaling represents an essential component of the regulatory network governing stress adaptation and virulence in A. pleuropneumoniae.

  14. Role of (pppGpp in Viability and Biofilm Formation of Actinobacillus pleuropneumoniae S8.

    Directory of Open Access Journals (Sweden)

    Gang Li

    Full Text Available Actinobacillus pleuropneumoniae is a Gram-negative bacterium and the cause of porcine pleuropneumonia. When the bacterium encounters nutritional starvation, the relA-dependent (pppGpp-mediated stringent response is activated. The modified nucleotides guanosine 5'-diphosphate 3'-diphosphate (ppGpp and guanosine 5'-triphosphate 3'-diphosphate (pppGpp are known to be signaling molecules in other prokaryotes. Here, to investigate the role of (pppGpp in A. pleuropneumoniae, we created a mutant A. pleuropneumoniae strain, S8ΔrelA, which lacks the (pppGpp-synthesizing enzyme RelA, and investigated its phenotype in vitro. S8ΔrelA did not survive after stationary phase (starvation condition and grew exclusively as non-extended cells. Compared to the wild-type (WT strain, the S8ΔrelA mutant had an increased ability to form a biofilm. Transcriptional profiles of early stationary phase cultures revealed that a total of 405 bacterial genes were differentially expressed (including 380 up-regulated and 25 down-regulated genes in S8ΔrelA as compared with the WT strain. Most of the up-regulated genes are involved in ribosomal structure and biogenesis, amino acid transport and metabolism, translation cell wall/membrane/envelope biogenesis. The data indicate that (pppGpp coordinates the growth, viability, morphology, biofilm formation and metabolic ability of A. pleuropneumoniae in starvation conditions. Furthermore, S8ΔrelA could not use certain sugars nor produce urease which has been associated with the virulence of A. pleuropneumoniae, suggesting that (pppGpp may directly or indirectly affect the pathogenesis of A. pleuropneumoniae during the infection process. In summary, (pppGpp signaling represents an essential component of the regulatory network governing stress adaptation and virulence in A. pleuropneumoniae.

  15. Determination of the spatiotemporal dependence of Pseudomonas aeruginosa biofilm viability after treatment with NLC-colistin

    Directory of Open Access Journals (Sweden)

    Sans-Serramitjana E

    2017-06-01

    Full Text Available Eulalia Sans-Serramitjana,1 Marta Jorba,1 José Luis Pedraz,2 Teresa Vinuesa,1 Miguel Viñas1 1Laboratory of Molecular Microbiology and Antimicrobials, Department of Pathology and Experimental Therapeutics, University of Barcelona, Barcelona, 2Laboratory of Pharmaceutics, University of the Basque Country (UPV/EHU, Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina, Vitoria, Spain Abstract: The emergence of colistin-resistant Pseudomonas aeruginosa in cystic fibrosis (CF patients, particularly after long-term inhalation treatments, has been recently reported. Nanoencapsulation may enable preparations to overcome the limitations of conventional pharmaceutical forms. We have determined the time-dependent viability of P. aeruginosa biofilms treated with both free and nanoencapsulated colistin. We also examined the relationship between the optimal anti-biofilm activity of nanostructured lipid carrier (NLC-colistin and the structural organization of the biofilm itself. The results showed the more rapid killing of P. aeruginosa bacterial biofilms by NLC-colistin than by free colistin. However, the two formulations did not differ in terms of the final percentages of living and dead cells, which were higher in the inner than in the outer layers of the treated biofilms. The effective anti-biofilm activity of NLC-colistin and its faster killing effect recommend further studies of its use over free colistin in the treatment of P. aeruginosa infections in CF patients. Keywords: cystic fibrosis, colistin sulfate, lipid nanoparticles, P. aeruginosa, confocal laser scanning microscopy, anti-biofilm activity

  16. Aerotaxis in Bacterial Turbulence

    Science.gov (United States)

    Fernandez, Vicente; Bisson, Antoine; Bitton, Cindy; Waisbord, Nicolas; Smriga, Steven; Rusconi, Roberto; Stocker, Roman

    2012-11-01

    Concentrated suspensions of motile bacteria exhibit correlated dynamics on spatial scales much larger than an individual bacterium. The resulting flows, visually similar to turbulence, can increase mixing and decrease viscosity. However, it remains unclear to what degree the collective dynamics depend on the motile behavior of bacteria at the individual level. Using a new microfluidic device to create controlled horizontal oxygen gradients, we studied the two dimensional behavior of dense suspensions of Bacillus subtilis. This system makes it possible to assess the interplay between the coherent large-scale motions of the suspension, oxygen transport, and the directional response of cells to oxygen gradients (aerotaxis). At the same time, this device has enabled us to examine the onset of bacterial turbulence and its influence on the propagation of the diffusing oxygen front, as the bacteria begin in a dormant state and transition to swimming when exposed to oxygen.

  17. Bacterial intermediate filaments

    DEFF Research Database (Denmark)

    Charbon, Godefroid; Cabeen, M.; Jacobs-Wagner, C.

    2009-01-01

    Crescentin, which is the founding member of a rapidly growing family of bacterial cytoskeletal proteins, was previously proposed to resemble eukaryotic intermediate filament (IF) proteins based on structural prediction and in vitro polymerization properties. Here, we demonstrate that crescentin...... also shares in vivo properties of assembly and dynamics with IF proteins by forming stable filamentous structures that continuously incorporate subunits along their length and that grow in a nonpolar fashion. De novo assembly of crescentin is biphasic and involves a cell size-dependent mechanism...... a new function for MreB and providing a parallel to the role of actin in IF assembly and organization in metazoan cells. Additionally, analysis of an MreB localization mutant suggests that cell wall insertion during cell elongation normally occurs along two helices of opposite handedness, each...

  18. Bacterial polyhydroxyalkanoates: Still fabulous?

    Science.gov (United States)

    Możejko-Ciesielska, Justyna; Kiewisz, Robert

    2016-11-01

    Bacterial polyhydroxyalkanoates (PHA) are polyesters accumulated as carbon and energy storage materials under limited growth conditions in the presence of excess carbon sources. They have been developed as biomaterials with unique properties for the past many years being considered as a potential substitute for conventional non-degradable plastics. Due to the increasing concern towards global climate change, depleting petroleum resource and problems with an utilization of a growing number of synthetic plastics, PHAs have gained much more attention from industry and research. These environmentally friendly microbial polymers have great potential in biomedical, agricultural, and industrial applications. However, their production on a large scale is still limited. This paper describes the backgrounds of PHAs and discussed the current state of knowledge on the polyhydroxyalkanoates. Ability of bacteria to convert different carbon sources to PHAs, the opportunities and challenges of their introduction to global market as valuable renewable products have been also discussed. Copyright © 2016 Elsevier GmbH. All rights reserved.

  19. Biosensors of bacterial cells.

    Science.gov (United States)

    Burlage, Robert S; Tillmann, Joshua

    2017-07-01

    Biosensors are devices which utilize both an electrical component (transducer) and a biological component to study an environment. They are typically used to examine biological structures, organisms and processes. The field of biosensors has now become so large and varied that the technology can often seem impenetrable. Yet the principles which underlie the technology are uncomplicated, even if the details of the mechanisms are elusive. In this review we confine our analysis to relatively current advancements in biosensors for the detection of whole bacterial cells. This includes biosensors which rely on an added labeled component and biosensors which do not have a labeled component and instead detect the binding event or bound structure on the transducer. Methods to concentrate the bacteria prior to biosensor analysis are also described. The variety of biosensor types and their actual and potential uses are described. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Bacterial proteases and virulence

    DEFF Research Database (Denmark)

    Frees, Dorte; Brøndsted, Lone; Ingmer, Hanne

    2013-01-01

    with the proteases either encoded within the same polypeptide or on separate subunits. In contrast, substrate recognition by extracellular proteases is less selective and therefore these enzymes are generally expressed as zymogens to prevent premature proteolytic activity that would be detrimental to the cell......Bacterial pathogens rely on proteolysis for variety of purposes during the infection process. In the cytosol, the main proteolytic players are the conserved Clp and Lon proteases that directly contribute to virulence through the timely degradation of virulence regulators and indirectly by providing...... signalling to short-circuit host cell processes. Common to both intra- and extracellular proteases is the tight control of their proteolytic activities. In general, substrate recognition by the intracellular proteases is highly selective which is, in part, attributed to the chaperone activity associated...

  1. The Genetic Structure of Natural Populations of DROSOPHILA MELANOGASTER. Xix. Genotype-Environment Interaction in Viability

    OpenAIRE

    Tachida, Hidenori; Mukai, Terumi

    1985-01-01

    To investigate whether or not an excess of additive genetic variance for viability detected in southern natural populations of Drosophila melanogaster was created by diversifying selection, genotype-environment interaction was tested as follows. (1) Two karyotype chromosomes were used: 61 second chromosomes with the standard karyotype and 63 second chromosomes carrying In(2L)t. Their homozygote viabilities were larger than 50% of the average viability of random heterozygotes. (2) The effect...

  2. Interrelation between viability of silkworm larvae Bombyx mori and natural electromagnetic fields

    Directory of Open Access Journals (Sweden)

    V. M. Litvin

    2006-12-01

    Full Text Available The interrelation of viability of silkworm larvae with natural electromagnetic fields is investigated. On the large statistical material found by the UAAS Institute of Sericulture for 50 years, it is shown, that the geomagnetic activity is characterized by weak influence on viability of larvae populations (4,7 %. The greatest caterpillars’ viability is observed in years of a high level of geomagnetic activity.

  3. Antimicrobial and cell viability measurement of bovine serum albumin capped silver nanoparticles (Ag/BSA) loaded collagen immobilized poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) film.

    Science.gov (United States)

    Bakare, Rotimi; Hawthrone, Samantha; Vails, Carmen; Gugssa, Ayele; Karim, Alamgir; Stubbs, John; Raghavan, Dharmaraj

    2016-03-01

    Bacterial infection of orthopedic devices has been a major concern in joint replacement procedures. Therefore, this study is aimed at formulating collagen immobilized poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) film loaded with bovine serum albumin capped silver nanoparticles (Ag/BSA NPs) to inhibit bacterial growth while retaining/promoting osteoblast cells viability. The nanoparticles loaded collagen immobilized PHBV film was characterized for its composition by X-ray Photoelectron Spectroscopy and Anodic Stripping Voltammetry. The extent of loading of Ag/BSA NPs on collagen immobilized PHBV film was found to depend on the chemistry of the functionalized PHBV film and the concentration of Ag/BSA NPs solution used for loading nanoparticles. Our results showed that more Ag/BSA NPs were loaded on higher molecular weight collagen immobilized PHEMA-g-PHBV film. Maximum loading of Ag/BSA NPs on collagen immobilized PHBV film was observed when 16ppm solution was used for adsorption studies. Colony forming unit and optical density measurements showed broad antimicrobial activity towards Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa at significantly lower concentration i.e., 0.19 and 0.31μg/disc, compared to gentamicin and sulfamethoxazole trimethoprim while MTT assay showed that released nanoparticles from Ag/BSA NPs loaded collagen immobilized PHBV film has no impact on MCTC3-E1 cells viability. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Bacteriële meningitis

    NARCIS (Netherlands)

    Brouwer, M. C.; van de Beek, D.

    2012-01-01

    Bacterial meningitis is a severe disease which affects 35.000 Europeans each year and has a mortality rate of about 20%. During the past 25 years the epidemiology of bacterial meningitis has changed significantly due to the implementation of vaccination against Haemophilus influenzae, Neisseria

  5. Bacterial meningitis in immunocompromised patients

    NARCIS (Netherlands)

    van Veen, K.E.B.

    2018-01-01

    Bacterial meningitis is an acute infection of the meninges, in The Netherlands most commonly caused by Streptococcus pneumoniae and Neisseria meningitides. Risk factors for acquiring bacterial meningitis include a decreased function of the immune system. The aim of this thesis was to study

  6. Monitoring the viability of citrus rootstocks seeds stored under refrigeration

    Directory of Open Access Journals (Sweden)

    Sérgio Alves de Carvalho

    2013-03-01

    Full Text Available The citrus nursery tree is produced through the bud grafting process, in which rootstock is usually grown from seed germination. The objective of this research was to evaluate, in two dissimilar environmental conditions, the viability and polyembryony expression of five citrus rootstocks seeds stored in different periods under refrigeration. The rootstock varieties evaluated were: Rangpur lime (Citrus limonia Osb. cv. Limeira, Trifoliate orange (Poncirus trifoliata Raf. cv. Limeira, Citrumelo (P. trifoliata x C. paradisi Macf. cv. Swingle, Sunki mandarin (C. sunki Hort. ex Tanaka and Volkamer lemon (C. volkameriana Ten. & Pasq. cv. Catania 2. The experimental design was the randomized blocks in a 11 x 5 x 2 factorial scheme, evaluating from time zero to the tenth month of storage, the five varieties of rootstock in two environments: germination and growth B.O.D type chamber (Biological Oxygen Demand - Eletrolab Brand Model FC 122 at 25 °C; and greenhouse seedbed with partial temperature control (22 °C to 36 °C and humidity control (75-85%. The plot had 24 seeds in four replicates, using trays with substrate in greenhouse and Petri dishes with filter paper in B.O.D. chamber. The seed germination rate and polyembryony expression were evaluated monthly. It was concluded that Trifoliate and Citrumelo Swingle seeds can be stored for up to seven months, while Volkamer lemon, Rangpur lime and Sunki seeds can be stored for up to ten months. The polyembryony expression rate was slightly higher when measured in greenhouse than in B.O.D. chamber and remained stable in both environments until the seventh month, from which dropped sharply. Citrumelo Swingle seeds expressed the highest polyembryony rate (18.8%, followed by Rangpur lime and Volkamer lemon (average value of 13.7%, Sunki (9.4% and Trifoliate (3.2%. Despite some differences among varieties, the viability of rootstock stored seeds can be monitored either in the greenhouse or in B

  7. Identifying genetic variants that affect viability in large cohorts.

    Directory of Open Access Journals (Sweden)

    Hakhamanesh Mostafavi

    2017-09-01

    Full Text Available A number of open questions in human evolutionary genetics would become tractable if we were able to directly measure evolutionary fitness. As a step towards this goal, we developed a method to examine whether individual genetic variants, or sets of genetic variants, currently influence viability. The approach consists in testing whether the frequency of an allele varies across ages, accounting for variation in ancestry. We applied it to the Genetic Epidemiology Research on Adult Health and Aging (GERA cohort and to the parents of participants in the UK Biobank. Across the genome, we found only a few common variants with large effects on age-specific mortality: tagging the APOE ε4 allele and near CHRNA3. These results suggest that when large, even late-onset effects are kept at low frequency by purifying selection. Testing viability effects of sets of genetic variants that jointly influence 1 of 42 traits, we detected a number of strong signals. In participants of the UK Biobank of British ancestry, we found that variants that delay puberty timing are associated with a longer parental life span (P~6.2 × 10-6 for fathers and P~2.0 × 10-3 for mothers, consistent with epidemiological studies. Similarly, variants associated with later age at first birth are associated with a longer maternal life span (P~1.4 × 10-3. Signals are also observed for variants influencing cholesterol levels, risk of coronary artery disease (CAD, body mass index, as well as risk of asthma. These signals exhibit consistent effects in the GERA cohort and among participants of the UK Biobank of non-British ancestry. We also found marked differences between males and females, most notably at the CHRNA3 locus, and variants associated with risk of CAD and cholesterol levels. Beyond our findings, the analysis serves as a proof of principle for how upcoming biomedical data sets can be used to learn about selection effects in contemporary humans.

  8. Determination of viability of preserved skin in low temperature

    International Nuclear Information System (INIS)

    Yang Hong Chang; Hao Zheng Ming; Zao Xiao Chun

    1999-01-01

    The skin from fresh human cadavers was stored in 4-18 degree C refrigerator. Before it was grafted for treatment of burn patients, it was quickly put into 40 degree C water and bring back to a former condition. The survival rate of skin was related with time and temperature of store. We used oxygen consumption to observe the change of viability of preserved skin. Oxygen consumption of skin was observed with apparatus made in the 304th Hospital of Peoples Liberation Army. The operating temperature was 5 - 45 degree C. Determination range was 0 - 199 mm Hg, resolving power of digital display was I mm Hg, instrumental error < 0.5 s'. Fresh human cadavers skin was made into 0.3 - 0.4 mm thick piece. Cleaned with NaCl 0.9% for three time. Then it was kept in neomycin solution for fifteen minutes. Then cut into 0.5 x 0.5 cm slices and stored in neomycin (2mg/ml). The skin was stored in 4 degree C refrigerator for five different periods (1, 2, 3, 5 and 7 days). Then the Oxygen consumption was determined immediately. The oxygen consumption was also determined before and after it was stored for 24 hours. After the skin was stored in 4 and -18 degree C for 24 hours the oxygen consumption was determined immediately. The prepared skin, which was stored in ordinary refrigerator, was useful and simple. The preserved skin was grafted onto the bum patient and survival rate was high and in short time. But the result showed the viability of preserved skin reduced with time. The result showed that the oxygen consumption of skin, which was stored at 4 degree C, on the fifth day was 62.23% and on day 7 was 30.5%. The study showed that the preserved skin which was stored at 4 degree C for five days was better while the vitality of skin evidently reduced after seven days and the survival rate was low. The oxygen consumption of preserved skin that was stored in -18 degree C refrigerator for 24 hours was 100%. But in 4 degree C refrigerator it was 89.1%. The result showed that the

  9. Viability criteria for steelhead of the south-central and southern California coast

    Science.gov (United States)

    Boughton, David A.; Adams, Peter B.; Anderson, Eric; Fusaro, Craig; Keller, Edward A.; Kelley, Elsie; Lentsch, Leo; Nielsen, Jennifer L.; Perry, Katie; Regan, Helen; Smith, Jerry; Swift, Camm C.; Thompson, Lisa; Watson, Fred

    2007-01-01

    Recovery planning for threatened and endangered steelhead requires measurable, objective criteria for determining an acceptably low risk of extinction. Here we propose viability criteria for two levels of biological organization: individual populations, and groups of populations within the SouthCentral/Southern California Coast Steelhead Recovery Planning Domain. For populations, we adapt criteria commonly used by the IUCN (The World Conservation Union) for identifying at-risk species. For groups of populations we implement a diversity-based “representation and redundancy rule,” in which diversity includes both life-history diversity and biogeographic groupings of populations. The resulting criteria have the potential for straightforward assessment of the risks posed by evolutionary, demographic, environmental, and catastrophic factors; and are designed to use data that are readily collected. However, our prescriptive approach led to one criterion whose threshold could not yet be specified due to inadequate data, and others in which the simplicity of the criteria may render them inefficient for populations with stable run sizes or stable life-history polymorphisms. Both of these problems could likely be solved by directed programs of research and monitoring aimed at developing more efficient (but equally risk-averse) “performance-based criteria.” Of particular utility would be data on the natural fluctuations of populations, research into the stabilizing influence of life-history polymorphisms, and research on the implications of drought, wildfires, and fluvial sediment regimes. Research on estuarine habitat could also yield useful information on the generality and reliability of its role as nursery habitat. Currently, risk assessment at the population level is not possible due to data deficiency, highlighting the need to implement a comprehensive effort to monitor run sizes, anadromous fractions, spawner densities and perhaps marine survival. Assessment at

  10. Molecular approaches for bacterial azoreductases

    Directory of Open Access Journals (Sweden)

    Montira Leelakriangsak

    2013-12-01

    Full Text Available Azo dyes are the dominant types of synthetic dyes, widely used in textiles, foods, leather, printing, tattooing, cosmetics, and pharmaceutical industries. Many microorganisms are able to decolorize azo dyes, and there is increasing interest in biological waste treatment methods. Bacterial azoreductases can cleave azo linkages (-N=N- in azo dyes, forming aromatic amines. This review mainly focuses on employing molecular approaches, including gene manipulation and recombinant strains, to study bacterial azoreductases. The construction of the recombinant protein by cloning and the overexpression of azoreductase is described. The mechanisms and function of bacterial azoreductases can be studied by other molecular techniques discussed in this review, such as RT-PCR, southern blot analysis, western blot analysis, zymography, and muta-genesis in order to understand bacterial azoreductase properties, function and application. In addition, understanding the regulation of azoreductase gene expression will lead to the systematic use of gene manipulation in bacterial strains for new strategies in future waste remediation technologies.

  11. Fish and fire: Post-wildfire sediment dynamics and implications for the viability of trout populations

    Science.gov (United States)

    Murphy, B. P.; Czuba, J. A.; Belmont, P.; Budy, P.; Finch, C.

    2017-12-01

    Episodic events in steep landscapes, such as wildfire and mass wasting, contribute large pulses of sediment to rivers and can significantly alter the quality and connectivity of fish habitat. Understanding where these sediment inputs occur, how they are transported and processed through the watershed, and their geomorphic effect on the river network is critical to predicting the impact on ecological aquatic communities. The Tushar Mountains of southern Utah experienced a severe wildfire in 2010, resulting in numerous debris flows and the extirpation of trout populations. Following many years of habitat and ecological monitoring in the field, we have developed a modeling framework that links post-wildfire debris flows, fluvial sediment routing, and population ecology in order to evaluate the impact and response of trout to wildfire. First, using the Tushar topographic and wildfire parameters, as well as stochastic precipitation generation, we predict the post-wildfire debris flow probabilities and volumes of mainstem tributaries using the Cannon et al. [2010] model. This produces episodic hillslope sediment inputs, which are delivered to a fluvial sediment, river-network routing model (modified from Czuba et al. [2017]). In this updated model, sediment transport dynamics are driven by time-varying discharge associated with the stochastic precipitation generation, include multiple grain sizes (including gravel), use mixed-size transport equations (Wilcock & Crowe [2003]), and incorporate channel slope adjustments with aggradation and degradation. Finally, with the spatially explicit adjustments in channel bed elevation and grain size, we utilize a new population viability analysis (PVA) model to predict the impact and recovery of fish populations in response to these changes in habitat. Our model provides a generalizable framework for linking physical and ecological models and for evaluating the extirpation risk of isolated fish populations throughout the

  12. Energy Recovery Linacs

    Energy Technology Data Exchange (ETDEWEB)

    Nikolitsa Merminga

    2007-06-01

    The success and continuing progress of the three operating FELs based on Energy Recovery Linacs (ERLs), the Jefferson Lab IR FEL Upgrade, the Japan Atomic Energy Agency (JAEA) FEL, and the Novosibirsk High Power THz FEL, have inspired multiple future applications of ERLs, which include higher power FELs, synchrotron radiation sources, electron cooling devices, and high luminosity electron-ion colliders. The benefits of using ERLs for these applications are presented. The key accelerator physics and technology challenges of realizing future ERL designs, and recent developments towards resolving these challenges are reviewed.

  13. Recovery of organic acids

    Science.gov (United States)

    Verser, Dan W.; Eggeman, Timothy J.

    2009-10-13

    A method is disclosed for the recovery of an organic acid from a dilute salt solution in which the cation of the salt forms an insoluble carbonate salt. A tertiary amine and CO.sub.2 are introduced to the solution to form the insoluble carbonate salt and a complex between the acid and an amine. A water immiscible solvent, such as an alcohol, is added to extract the acid/amine complex from the dilute salt solution to a reaction phase. The reaction phase is continuously dried and a product between the acid and the solvent, such as an ester, is formed.

  14. Recovery of organic acids

    Science.gov (United States)

    Verser, Dan W [Menlo Park, CA; Eggeman, Timothy J [Lakewood, CO

    2011-11-01

    A method is disclosed for the recovery of an organic acid from a dilute salt solution in which the cation of the salt forms an insoluble carbonate salt. A tertiary amine and CO.sub.2 are introduced to the solution to form the insoluble carbonate salt and a complex between the acid and an amine. A water immiscible solvent, such as an alcohol, is added to extract the acid/amine complex from the dilute salt solution to a reaction phase. The reaction phase is continuously dried and a product between the acid and the solvent, such as an ester, is formed.

  15. Waste heat recovery system

    International Nuclear Information System (INIS)

    Phi Wah Tooi

    2010-01-01

    Full text: The Konzen in-house designed anaerobic digester system for the POME (Palm Oil Mill Effluent) treatment process is one of the registered Clean Development Mechanism (CDM) projects in Malaysia. It is an organic wastewater treatment process which achieves excellent co-benefits objectives through the prevention of water pollution and reduction of greenhouse gas emissions, which is estimated to be 40,000 to 50,000 t-CO 2 per year. The anaerobic digester was designed in mesophile mode with temperature ranging from 37 degree Celsius to 45 degree Celsius. A microorganisms growth is optimum under moderately warm temperature conditions. The operating temperature of the anaerobic digester needs to be maintained constantly. There are two waste heat recovery systems designed to make the treatment process self-sustaining. The heat recovered will be utilised as a clean energy source to heat up the anaerobic digester indirectly. The first design for the waste heat recovery system utilises heat generated from the flue gas of the biogas flaring system. A stainless steel water tank with an internal water layer is installed at the top level of the flare stack. The circulating water is heated by the methane enriched biogas combustion process. The second design utilizes heat generated during the compression process for the biogas compressor operation. The compressed biogas needs to be cooled before being recycled back into the digester tank for mixing purposes. Both the waste heat recovery systems use a design which applies a common water circulation loop and hot water tank to effectively become a closed loop. The hot water tank will perform both storage and temperature buffer functions. The hot water is then used to heat up recycled sludge from 30 degree Celsius to 45 degree Celsius with the maximum temperature setting at 50 degree Celsius. The recycled sludge line temperature will be measured and monitored by a temperature sensor and transmitter, which will activate the

  16. Pyrolysis with staged recovery

    Science.gov (United States)

    Green, Norman W.; Duraiswamy, Kandaswamy; Lumpkin, Robert E.; Winter, Bruce L.

    1979-03-20

    In a continuous process for recovery of values contained in a solid carbonaceous material, the carbonaceous material is comminuted and then subjected to flash pyrolysis in the presence of a particulate heat source fed over an overflow weir to form a pyrolysis product stream containing a carbon containing solid residue and volatilized hydrocarbons. After the carbon containing solid residue is separated from the pyrolysis product stream, values are obtained by condensing volatilized hydrocarbons. The particulate source of heat is formed by oxidizing carbon in the solid residue.

  17. Mixed response in bacterial and biochemical variables to simulated sand mining in placer-rich beach sediments, Ratnagiri, West coast of India.

    Science.gov (United States)

    Fernandes, Christabelle E G; Das, Anindita; Nath, B N; Faria, Daphne G; Loka Bharathi, P A

    2012-05-01

    We investigated the influence on bacterial community and biochemical variables through mechanical disturbance of sediment-akin to small-scale mining in Kalbadevi beach, Ratnagiri, a placer-rich beach ecosystem which is a potential mining site. Changes were investigated by comparing three periods, namely phase I before disturbance, phase II just after disturbance, and phase III 24 h after disturbance as the bacterial generation time is ≤7 h. Cores from dune, berm, high-, mid-, and low-tide were examined for changes in distribution of total bacterial abundance, total direct viability (counts under aerobic and anaerobic conditions), culturability and biochemical parameters up to 40 cm depth. Results showed that bacterial abundance decreased by an order from 10(6) cells g(-1) sediment, while, viability reduced marginally. Culturability on different-strength nutrient broth increased by 155% during phase II. Changes in sedimentary proteins, carbohydrates, and lipids were marked at berm and dune and masked at other levels by tidal influence. Sedimentary ATP reduced drastically. During phase III, Pearson's correlation between these variables evolved from non-significant to significant level. Thus, simulated disturbance had a mixed effect on bacterial and biochemical variables of the sediments. It had a negative impact on bacterial abundance, viability and ATP but positive impact on culturability. Viability, culturability, and ATP could act as important indicators reflecting the disturbance in the system at short time intervals. Culturability, which improved by an order, could perhaps be a fraction that contributes to restoration of the system at bacterial level. This baseline information about the potential mining site could help in developing rational approach towards sustainable harnessing of resources with minimum damage to the ecosystem.

  18. DNA recovery from soils of diverse composition.

    Science.gov (United States)

    Zhou, J; Bruns, M A; Tiedje, J M

    1996-02-01

    A simple, rapid method for bacterial lysis and direct extraction of DNA from soils with minimal shearing was developed to address the risk of chimera formation from small template DNA during subsequent PCR. The method was based on lysis with a high-salt extraction buffer (1.5 M NaCl) and extended heating (2 to 3 h) of the soil suspension in the presence of sodium dodecyl sulfate (SDS), hexadecyltrimethylammonium bromide, and proteinase K. The extraction method required 6 h and was tested on eight soils differing in organic carbon, clay content, and pH, including ones from which DNA extraction is difficult. The DNA fragment size in crude extracts from all soils was > 23 kb. Preliminary trials indicated that DNA recovery from two soils seeded with gram-negative bacteria was 92 to 99%. When the method was tested on all eight unseeded soils, microscopic examination of indigenous bacteria in soil pellets before and after extraction showed variable cell lysis efficiency (26 to 92%). Crude DNA yields from the eight soils ranged from 2.5 to 26.9 micrograms of DNA g-1, and these were positively correlated with the organic carbon content in the soil (r = 0.73). DNA yields from gram-positive bacteria from pure cultures were two to six times higher when the high-salt-SDS-heat method was combined with mortar-and-pestle grinding and freeze-thawing, and most DNA recovered was of high molecular weight. Four methods for purifying crude DNA were also evaluated for percent recovery, fragment size, speed, enzyme restriction, PCR amplification, and DNA-DNA hybridization. In general, all methods produced DNA pure enough for PCR amplification. Since soil type and microbial community characteristics will influence DNA recovery, this study provides guidance for choosing appropriate extraction and purification methods on the basis of experimental goals.

  19. Viability and heat resistance of murine norovirus on bread.

    Science.gov (United States)

    Takahashi, Michiko; Takahashi, Hajime; Kuda, Takashi; Kimura, Bon

    2016-01-04

    Contaminated bread was the cause of a large-scale outbreak of norovirus disease in Japan in 2014. Contamination of seafood and uncooked food products by norovirus has been reported several times in the past; however the outbreak resulting from the contamination of bread products was unusual. A few reports on the presence of norovirus on bread products are available; however there have been no studies on the viability and heat resistance of norovirus on breads, which were investigated in this study. ce:italic>/ce:italic> strain 1 (MNV-1), a surrogate for human norovirus, was inoculated directly on 3 types of bread, but the infectivity of MNV-1 on bread samples was almost unchanged after 5days at 20°C. MNV-1 was inoculated on white bread that was subsequently heated in a toaster for a maximum of 2min. The results showed that MNV-1 remained viable if the heating period was insufficient to inactivate. In addition, bread dough contaminated with MNV-1 was baked in the oven. Our results indicated that MNV-1 may remain viable on breads if the heating duration or temperature is insufficient. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Viability of microencapsulated Lactobacillus casei in synbiotic mayonnaise

    Directory of Open Access Journals (Sweden)

    Lieu, M.D.

    2017-07-01

    Full Text Available In this study, whey protein, maltodextrin and GOS (Galacto-oligosaccharides used as microencapsulating agents to protect Lactobacillus casei during spray-drying and mayonnaise storage. The morphology of microcapsules, pH charges, the survival rate during mayonnaise storage as well as survival in simulated gastric fluid (SGF and intestinal fluid (SIF was tested in this study. The results indicated that whey protein showed a protective effect better than maltodextrin during spray-drying. The particles showed spherical shape and typical concavity of all samples and encapsulating agents were not affected by the size and surface structure of particles. The pH charges were not significantly different in all mayonnaise samples in this test. The viability of free cell L. casei after 6 weeks storage was significant decrease about 4 log CFU/g compared to 1.55 to 3.27 log CFU/g in the mayonnaise samples containing microcapsules in which maltodextrin showed the lowest of L. casei survival rate. In SGF and SIF conditions, maltodextrin act as prebiotic sufficiently which do not need adding GOS. The combination of whey protein and maltodextrin in which maltodextrin plays a role as supporting agents for the spray-drying process as well as prebiotic potential, while whey protein with high buffer property which enhancing the survival rate of L. casie in low pH.

  1. Incorporating parametric uncertainty into population viability analysis models

    Science.gov (United States)

    McGowan, Conor P.; Runge, Michael C.; Larson, Michael A.

    2011-01-01

    Uncertainty in parameter estimates from sampling variation or expert judgment can introduce substantial uncertainty into ecological predictions based on those estimates. However, in standard population viability analyses, one of the most widely used tools for managing plant, fish and wildlife populations, parametric uncertainty is often ignored in or discarded from model projections. We present a method for explicitly incorporating this source of uncertainty into population models to fully account for risk in management and decision contexts. Our method involves a two-step simulation process where parametric uncertainty is incorporated into the replication loop of the model and temporal variance is incorporated into the loop for time steps in the model. Using the piping plover, a federally threatened shorebird in the USA and Canada, as an example, we compare abundance projections and extinction probabilities from simulations that exclude and include parametric uncertainty. Although final abundance was very low for all sets of simulations, estimated extinction risk was much greater for the simulation that incorporated parametric uncertainty in the replication loop. Decisions about species conservation (e.g., listing, delisting, and jeopardy) might differ greatly depending on the treatment of parametric uncertainty in population models.

  2. Nuclear hydrogen: An assessment of product flexibility and market viability

    International Nuclear Information System (INIS)

    Botterud, Audun; Yildiz, Bilge; Conzelmann, Guenter; Petri, Mark C.

    2008-01-01

    Nuclear energy has the potential to play an important role in the future energy system as a large-scale source of hydrogen without greenhouse gas emissions. Thus far, economic studies of nuclear hydrogen tend to focus on the levelized cost of hydrogen without accounting for the risks and uncertainties that potential investors would face. We present a financial model based on real options theory to assess the profitability of different nuclear hydrogen production technologies in evolving electricity and hydrogen markets. The model uses Monte Carlo simulations to represent uncertainty in future hydrogen and electricity prices. It computes the expected value and the distribution of discounted profits from nuclear hydrogen production plants. Moreover, the model quantifies the value of the option to switch between hydrogen and electricity production, depending on what is more profitable to sell. We use the model to analyze the market viability of four potential nuclear hydrogen technologies and conclude that flexibility in output product is likely to add significant economic value for an investor in nuclear hydrogen. This should be taken into account in the development phase of nuclear hydrogen technologies

  3. Adverse respiratory outcome after premature rupture of membranes before viability.

    Science.gov (United States)

    Verspyck, Eric; Bisson, Violene; Roman, Horace; Marret, Stéphane

    2014-03-01

    To determine whether preterm premature rupture of membranes (PPROM) before 24 weeks is an independent risk factor for poor outcome in preterm neonates. A retrospective comparative cohort study was conducted, including viable premature infants born between 25 and 34-weeks gestation. Each preterm case with early PPROM was matched with two preterm controls of the same gestational age at birth, sex and birth date and who were born spontaneously with intact membranes. Logistic regression was performed to identify independent risk factors associated with composite respiratory and perinatal adverse outcomes for the overall population of preterm infants. Thirty-five PPROM cases were matched with 70 controls. Extreme prematurity (26-28 weeks) was an independent risk factor for composite perinatal adverse outcomes [odds ratio (OR) 43.9; p = 0.001]. Extreme prematurity (OR 42.9; p = 0.001), PPROM (OR 7.1; p = 0.01), male infant (OR 5.2; p = 0.02) and intrauterine growth restriction (IUGR, OR 4.8; p = 0.04) were factors for composite respiratory adverse outcomes. Preterm premature rupture of membranes before viability represents an independent risk factor for composite respiratory adverse outcomes in preterm neonates. Extreme prematurity may represent the main risk factor for both composite respiratory and perinatal adverse outcomes. ©2013 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  4. Viability of osteocytes in bone autografts harvested for dental implantology

    International Nuclear Information System (INIS)

    Guillaume, Bernard; Gaudin, Christine; Georgeault, Sonia; Mallet, Romain; Basle, Michel F; Chappard, Daniel

    2009-01-01

    Bone autograft remains a very useful and popular way for filling bone defects. In maxillofacial surgery or implantology, it is used to increase the volume of the maxilla or mandible before placing dental implants. Because there is a noticeable delay between harvesting the graft and its insertion in the receiver site, we evaluated the morphologic changes at the light and transmission electron microscopy levels. Five patients having an autograft (bone harvested from the chin) were enrolled in the study. A small fragment of the graft was immediately fixed after harvesting and a second one was similarly processed at the end of the grafting period when bone has been stored at room temperature for a 20 min ± 33 s period in saline. A net increase in the number of osteocyte lacunae filled with cellular debris was observed (+41.5%). However no cytologic alteration could be observed in the remaining osteocytes. The viability of these cells is known to contribute to the success of autograft in association with other less well-identified factors.

  5. A note on the viability of Gauss-Bonnet cosmology

    International Nuclear Information System (INIS)

    Chingangbam, R.; Sami, M.; Tretyakov, P.V.; Toporensky, A.V.

    2008-01-01

    In this Letter, we analyze the viability of a vacuum Gauss-Bonnet cosmology by examining the dynamics of the homogeneous and anisotropic background in 4+1 dimensions. The trajectories of the system either originate from the standard singularity or from non-standard type, the later is characterized by the divergence of time derivative of the Hubble parameters for its finite value. At the onset, the system should relax to Einstein phase at late times as the effect of Gauss-Bonnet term becomes negligible in the low energy regime. However, we find that most of the trajectories emerging from the standard big-bang singularity lead to future re-collapse whereas the system beginning its evolution from the non-standard singularity enters the Kasner regime at late times. This leads to the conclusion that the measure of trajectories giving rise to a smooth evolution from a standard singularity to the Einstein phase is negligibly small for generic initial conditions

  6. Chemicals and lemon essential oil effect on Alicyclobacillus acidoterrestris viability

    Directory of Open Access Journals (Sweden)

    Maria Cristina Maldonado

    2013-12-01

    Full Text Available Alicyclobacillus acidoterrestris is considered to be one of the important target microorganisms in the quality control of acidic canned foods. There is an urgent need to develop a suitable method for inhibiting or controlling the germination and outgrowth of A.acidoterrestris in acidic drinks. The aim of this work was to evaluate the chemicals used in the lemon industry (sodium benzoate, potassium sorbate, and lemon essential oil as a natural compound, against a strain of A.acidoterrestris in MEB medium and in lemon juice concentrate. The results pointed out that sodium benzoate (500-1000-2000 ppm and lemon essential oil (0.08- 0.12- 0.16% completely inhibited the germination of A. acidoterrestris spores in MEB medium and LJC for 11 days. Potassium sorbate (600-1200 ppm was more effective to inhibit the growth of the microbial target in lemon juice than in MEB medium. The effect of sodium benzoate, potassium sorbate and essential oil was sporostatic in MEB and LJC as they did not affect spore viability.

  7. Evaluating the Viability of Mobile Learning to Enhance Management Training

    Directory of Open Access Journals (Sweden)

    Iain Macdonald

    2011-04-01

    Full Text Available A qualitative research project was conducted to test the viability of augmenting an e-learning program for workplace learners using mobile content delivered through smart phones. Ten learners taking a six week web-based e-learning course were given smart phones which enabled them to access approximately 70% of the course content, in addition to having access to the full course via a standard e-learning website. Mobile content was provided in a variety of forms, including text, audio and video files, a mobile multiple-choice quiz website, and links to streaming videos. Study participants who were regular users of mobile phones found the mobile learning materials to be user-friendly, offering increased convenience and flexibility. Use of the mobile content tended to increase as learners spent more time in their day away from locations where Internet-linked computers could be found. Video was found to be the most effective means of presenting content, followed by audio and text. The most promising role of mobile learning appears to be to augment rather than replace e-learning or blended learning.

  8. Viability of the health protection account in Hong Kong.

    Science.gov (United States)

    Law, C K; Yip, P S F

    2002-08-01

    To evaluate the viability of the Health Protection Account proposed by the Hong Kong Special Administrative Region Government. Retrospective study. The Hospital Authority of Hong Kong. Data were obtained from hospital and specialist out-patient clinic admissions. The expected health cost for each patient from the age of 65 years to the average age of life expectancy (83 years) was estimated, as was the contribution to these health costs from the Health Protection Account. If individuals contribute 1% of their salary to the Health Protection Account from age 40 to 65 years, the Account can only cover 4% of the actual health costs. The Health Protection Account, as proposed, does not ease the financial burden of increasing health care costs in the elderly. Increasing the contribution rate or reducing the age at which contributions to the scheme are started are possible viable options for making the scheme sustainable. However, the current economic situation is such that the public would not favour either of these alternatives. It is envisaged that the Government will need to continue to finance the health care of its citizens by taxation. A gradual increase in user charges might be the only future option for controlling government health expenditure.

  9. Viability of biocompatible and biodegradable seeds production with incorporated radionuclides

    International Nuclear Information System (INIS)

    Roberto, W.S.; Pereira, M.M.; Vasconcelos, W.L.; Campos, T.P.R.

    2000-01-01

    The present work aims the development of radioactive seeds, biocompatible and biodegradable, with the objective of adding options in the cancer treatment. The work focus on the production of seeds biodegradable that incorporate radioisotopes with half life inferior than the degradation time of the material. The idea of producing devices with biodegradable materials impregnated with radioisotopes of short half life will offer new possibilities in the cancer treatment, since they can be used following the same procedures of the permanent interstitial brachytherapy, but using degradable materials compatible with the physiological environment. It will be discussed in particular the possible application of these seeds in the treatment of prostate cancer. A review of the subject and a preliminary evaluation of the viability of production of the seeds will be presented. The method of production of the seeds is based on the incorporation of Iodine and Samarium in glass matrixes obtained by sol-gel processing. X-ray fluorescence was done in the samples produced and the incorporation of Iodine and Samarium atoms was confirmed. (author)

  10. Bone graft viability evaluated by three phase bone scan

    International Nuclear Information System (INIS)

    Ljiljana Jaukovic Rajko Spaic; Marijan Novakovic; Srbislav Stosic

    2004-01-01

    Bone defects resulting war injury can be replaced by microvascular bone grafts from fibula. Aim: The aim of this study was to assess the value of three phase (3P) bone scintigraphy in the early detection of the bone graft complications. Method: 3P bone scans were performed in four patients (two after mandible reconstruction with micro vascular fibular bone grafts, one after fibular transplantation for ulnar and one with humeral reconstruction). First dynamic phase scan was performed immediately after iv injection of 740 MBq Tc- 99m DPD, acquiring 15 two seconds duration frames. Second, early static scan was performed during next 300 seconds, and third, delayed scan three hours later. All scans were obtained under the bone graft region. The scans were evaluated using ROI under graft region and the corresponding contra lateral area. Blood flow in graft region was determined using first phase scan, and tracer uptake in the same region was determined using second and third phase scans. Results: in all patients blood flow in graft region was particularly normal. Tracer uptake in one of two patients with mandible reconstruction was diffusely increased in graft, strongly suggesting infection; In the other patient delayed scan showed no tracer uptake in graft center .Both patients with ulnar and humeral reconstruction showed only slightly decreased tracer uptake in bone grafts. 3 phase bone scintigraphy may play a role in the evaluation of bone graft viability by predicting the infection and necrosis. (authors)

  11. A Method for Quantitative Determination of Biofilm Viability

    Directory of Open Access Journals (Sweden)

    Maria Strømme

    2012-06-01

    Full Text Available In this study we present a scheme for quantitative determination of biofilm viability offering significant improvement over existing methods with metabolic assays. Existing metabolic assays for quantifying viable bacteria in biofilms usually utilize calibration curves derived from planktonic bacteria, which can introduce large errors due to significant differences in the metabolic and/or growth rates of biofilm bacteria in the assay media compared to their planktonic counterparts. In the presented method we derive the specific growth rate of Streptococcus mutans bacteria biofilm from a series of metabolic assays using the pH indicator phenol red, and show that this information could be used to more accurately quantify the relative number of viable bacteria in a biofilm. We found that the specific growth rate of S. mutans in biofilm mode of growth was 0.70 h−1, compared to 1.09 h−1 in planktonic growth. This method should be applicable to other bacteria types, as well as other metabolic assays, and, for example, to quantify the effect of antibacterial treatments or the performance of bactericidal implant surfaces.

  12. Open pit coal exploitation viability. Margarita mine. Case of study

    International Nuclear Information System (INIS)

    Veloza, Julia; Molina, Jorge; Mejia, Humberto

    2006-01-01

    This paper provides an analysis of financial viability, planning and design for the new coal open pit exploitation for La Margarita mine, with coal-resources estimated on 440.139,7 ton. Dimension, design and economic evaluation were possible by three exploitation methods: (multiple bench, open cast contour, and terraces). Net present values (NVP) were calculated: $c 817,5; $c 518,5 and $c 645,2 respectively for each method (given in million current Colombian pesos $. $c 2380 are equivalent to $us 1) and rate of return (ROR) 78,33%; 34,0% and 38,62% respectively for each method. These indicators served as a parameter to choose the multiple bench method, which should be recalculated because it was necessary to work jointly with two pits and making feasible the project. in addition a general environmental evaluation was done, which is vital for the exploitation. Important impacts on the flower, animals, air, water were found, and measures of control, prevention and mitigation were stated. it is expected that this paper can be useful as a technical-economical support for the development of the open pit exploitation in the margarita mine

  13. Effect of storage temperature on survival and recovery of thermal and extrusion injured Escherichia coli populations in whey protein concentrate and corn meal

    Science.gov (United States)

    In a previous study, we reported viability loss of Escherichia coli populations in corn (CP) and whey protein products (WPP) extruded at different temperatures. However, information on the effect of storage temperatures on injured bacterial populations was not addressed. The objective of this study ...

  14. Zoonotic bacterial meningitis in human adults

    NARCIS (Netherlands)

    van Samkar, Anusha; Brouwer, Matthijs C.; van der Ende, Arie; van de Beek, Diederik

    2016-01-01

    To describe the epidemiology, etiology, clinical characteristics, treatment, outcome, and prevention of zoonotic bacterial meningitis in human adults. We identified 16 zoonotic bacteria causing meningitis in adults. Zoonotic bacterial meningitis is uncommon compared to bacterial meningitis caused by

  15. Effect of freeze-drying on viability and in vitro probiotic properties of a mixture of lactic acid bacteria and yeasts isolated from kefir.

    Science.gov (United States)

    Bolla, Patricia A; Serradell, María de los Angeles; de Urraza, Patricio J; De Antoni, Graciela L

    2011-02-01

    The effect of freeze-drying on viability and probiotic properties of a microbial mixture containing selected bacterial and yeast strains isolated from kefir grains (Lactobacillus kefir, Lactobacillus plantarum, Lactococcus lactis, Saccharomyces cerevisiae and Kluyveromyces marxianus) was studied. The microorganisms were selected according to their potentially probiotic properties in vitro already reported. Two types of formulations were performed, a microbial mixture (MM) suspended in milk and a milk product fermented with MM (FMM). To test the effect of storage on viability of microorganisms, MM and FMM were freeze-dried and maintained at 4°C for six months. After 180 days of storage at 4°C, freeze-dried MM showed better survival rates for each strain than freeze-dried FMM. The addition of sugars (trehalose or sucrose) did not improve the survival rates of any of the microorganisms after freeze-drying. Freeze-drying did not affect the capacity of MM to inhibit growth of Shigella sonnei in vitro, since the co-incubation of this pathogen with freeze-dried MM produced a decrease of 2 log in Shigella viability. The safety of freeze-dried MM was tested in mice and non-translocation of microorganisms to liver or spleen was observed in BALB/c mice feed ad libitum during 7 or 20 days. To our knowledge, this is the first report about the effect of freeze-drying on viability, in vitro probiotic properties and microbial translocation of a mixture containing different strains of both bacteria and yeasts isolated from kefir.

  16. A selective medium for recovery and enumeration of endolithic bacteria.

    Science.gov (United States)

    Bhattacharjee, Kaushik; Joshi, S R

    2016-10-01

    The study of lithic microbial communities, inhabiting rock substrates has been gathering momentum due to a growing attention of their wide importance as model systems in ecological studies and for their community structure. It is generally accepted that the success of cultivation-based technique is primarily based on suitable culture medium for isolation. The media available for enumeration and recovery of endolithic bacteria are mainly specific to particular type of rock which may not be suitable to isolate endolithic bacterial community from diverse lithobiontic niches. In this study, a new unoptimized medium was formulated, designated LM10 (unoptimized) for enumeration and recovery of endolithic bacteria by addition and/or omission of media components to the basal medium R2G, which was selected after experimental evaluation of five different existing media. The endolithic bacterial count in LM10 medium (unoptimized) was significantly higher than the R2G medium (t=-12.57, pmedium were optimized using statistical approach to maximize the recovery and enumeration of endolithic bacteria. The first phase of the study comprised of a Plackett-Burman (PB) design experiment conducted to screen thirteen medium components and two culture parameters as variables with effect on bacterial enumeration and recovery. Out of these, Yeast extract, Casein hydrolysate, Glucose, Starch and Sodium thiosulphate were found to be significantly affecting the bacterial count (p0.05 and coefficients), further optimization was carried out for significant factors using Box-Behnken design (BBD) of response surface methodology (RSM). Optimized media components obtained by BBD were Yeast extract, Casein hydrolysate, Glucose and Starch in 0.05g/l each and Sodium thiosulphate in 0.047g/l concentrations. The composition of optimized LM10 medium formulated (per litre) is 0.05g Yeast extract, 0.05g Casein hydrolysate, 0.05g Glucose, 0.05g Starch, 0.01g K2HPO4, 0.02g Sodium pyruvate, 0.2g MgSO4, 0

  17. Micro-Organisms In Enhanced Oil Recovery | Osunde | Ife Journal of ...

    African Journals Online (AJOL)

    The extent of bacterial involvement in petroleum genesis has been a subject of debate even while evidence indicates that million years of heat and pressure changed the remains of microscopic plants and animals into oil and natural gas. Microbial-enhanced oil recovery (MEOR) involves processes where microorganisms ...

  18. In vivo assessment of myocardial viability after acute myocardial infarction: A head-to-head comparison of the perfusable tissue index by PET and delayed contrast-enhanced CMR.

    Science.gov (United States)

    Timmer, Stefan A J; Teunissen, Paul F A; Danad, Ibrahim; Robbers, Lourens F H J; Raijmakers, Pieter G H M; Nijveldt, Robin; van Rossum, Albert C; Lammertsma, Adriaan A; van Royen, Niels; Knaapen, Paul

    2017-04-01

    Early recognition of viable myocardium after acute myocardial infarction (AMI) is of clinical relevance, since affected segments have the potential of functional recovery. Delayed contrast-enhanced magnetic resonance imaging (DCE-CMR) has been validated extensively for the detection of viable myocardium. An alternative parameter for detecting viability is the perfusable tissue index (PTI), derived using [ 15 O]H 2 O positron emission tomography (PET), which is inversely related to the extent of myocardial scar (non-perfusable tissue). The aim of the present study was to investigate the predictive value of PTI on recovery of LV function as compared to DCE-CMR in patients with AMI, after successful percutaneous coronary intervention (PCI). Thirty-eight patients with ST elevation myocardial infarction (STEMI) successfully treated by PCI were prospectively recruited. Subjects were examined 1 week and 3 months (mean follow-up time: 97 ± 10 days) after AMI using [ 15 O]H 2 O PET and DCE-CMR to assess PTI, regional function and scar. Viability was defined as recovery of systolic wall thickening ≥3.0 mm at follow-up by use of CMR. A total of 588 segments were available for serial analysis. At baseline, 180 segments were dysfunctional and exhibited DCE. Seventy-three (41%) of these dysfunctional segments showed full recovery during follow-up (viable), whereas 107 (59%) segments remained dysfunctional (nonviable). Baseline PTI of viable segments was 0.94 ± 0.09 and was significantly higher compared to nonviable segments (0.80 ± 0.13, P myocardial viability shortly after reperfused AMI is feasible using PET. PET-derived PTI yields a good predictive value for the recovery of LV function in PCI-treated STEMI patients, in excellent agreement with DCE-CMR.

  19. Evolution of Bacterial Suicide

    Science.gov (United States)

    Tchernookov, Martin; Nemenman, Ilya

    2013-03-01

    While active, controlled cellular suicide (autolysis) in bacteria is commonly observed, it has been hard to argue that autolysis can be beneficial to an individual who commits it. We propose a theoretical model that predicts that bacterial autolysis is evolutionarily advantageous to an individualand would fixate in physically structured environments for stationary phase colonies. We perform spatially resolved agent-based simulations of the model, which predict that lower mixing in the environment results in fixation of a higher autolysis rate from a single mutated cell, regardless of the colony's genetic diversity. We argue that quorum sensing will fixate as well, even if initially rare, if it is coupled to controlling the autolysis rate. The model does not predict a strong additional competitive advantage for cells where autolysis is controlled by quorum sensing systems that distinguish self from nonself. These predictions are broadly supported by recent experimental results in B. subtilisand S. pneumoniae. Research partially supported by the James S McDonnell Foundation grant No. 220020321 and by HFSP grant No. RGY0084/2011.

  20. Electromagnetism of Bacterial Growth

    Science.gov (United States)

    Ainiwaer, Ailiyasi

    2011-10-01

    There has been increasing concern from the public about personal health due to the significant rise in the daily use of electrical devices such as cell phones, radios, computers, GPS, video games and television. All of these devices create electromagnetic (EM) fields, which are simply magnetic and electric fields surrounding the appliances that simultaneously affect the human bio-system. Although these can affect the human system, obstacles can easily shield or weaken the electrical fields; however, magnetic fields cannot be weakened and can pass through walls, human bodies and most other objects. The present study was conducted to examine the possible effects of bacteria when exposed to magnetic fields. The results indicate that a strong causal relationship is not clear, since different magnetic fields affect the bacteria differently, with some causing an increase in bacterial cells, and others causing a decrease in the same cells. This phenomenon has yet to be explained, but the current study attempts to offer a mathematical explanation for this occurrence. The researchers added cultures to the magnetic fields to examine any effects to ion transportation. Researchers discovered ions such as potassium and sodium are affected by the magnetic field. A formula is presented in the analysis section to explain this effect.

  1. Effect of UV-photofunctionalization on oral bacterial attachment and biofilm formation to titanium implant material.

    Science.gov (United States)

    de Avila, Erica Dorigatti; Lima, Bruno P; Sekiya, Takeo; Torii, Yasuyoshi; Ogawa, Takahiro; Shi, Wenyuan; Lux, Renate

    2015-10-01

    Bacterial biofilm infections remain prevalent reasons for implant failure. Dental implant placement occurs in the oral environment, which harbors a plethora of biofilm-forming bacteria. Due to its trans-mucosal placement, part of the implant structure is exposed to oral cavity and there is no effective measure to prevent bacterial attachment to implant materials. Here, we demonstrated that UV treatment of titanium immediately prior to use (photofunctionalization) affects the ability of human polymicrobial oral biofilm communities to colonize in the presence of salivary and blood components. UV-treatment of machined titanium transformed the surface from hydrophobic to superhydrophilic. UV-treated surfaces exhibited a significant reduction in bacterial attachment as well as subsequent biofilm formation compared to untreated ones, even though overall bacterial viability was not affected. The function of reducing bacterial colonization was maintained on UV-treated titanium that had been stored in a liquid environment before use. Denaturing gradient gel-electrophoresis (DGGE) and DNA sequencing analyses revealed that while bacterial community profiles appeared different between UV-treated and untreated titanium in the initial attachment phase, this difference vanished as biofilm formation progressed. Our findings confirm that UV-photofunctionalization of titanium has a strong potential to improve outcome of implant placement by creating and maintaining antimicrobial surfaces. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Effect of UV-photofunctionalization on Oral Bacterial Attachment and Biofilm Formation to Titanium Implant Material

    Science.gov (United States)

    de Avila, Erica Dorigatti; Lima, Bruno P.; Sekiya, Takeo; Torii, Yasuyoshi; Ogawa, Takahiro; Shi, Wenyuan; Lux, Renate

    2015-01-01

    Bacterial biofilm infections remain prevalent reasons for implant failure. Dental implant placement occurs in the oral environment, which harbors a plethora of biofilm-forming bacteria. Due to its trans-mucosal placement, part of the implant structure is exposed to oral cavity and there is no effective measure to prevent bacterial attachment to implant materials. Here, we demonstrated that UV treatment of titanium immediately prior to use (photofunctionalization) affects the ability of human polymicrobial oral biofilm communities to colonize in the presence of salivary and blood components. UV-treatment of machined titanium transformed the surface from hydrophobic to superhydrophilic. UV-treated surfaces exhibited a significant reduction in bacterial attachment as well as subsequent biofilm formation compared to untreated ones, even though overall bacterial viability was not affected. The function of reducing bacterial colonization was maintained on UV-treated titanium that had been stored in a liquid environment before use. Denaturing gradient gel-electrophoresis (DGGE) and DNA sequencing analyses revealed that while bacterial community profiles appeared different between UV-treated and untreated titanium in the initial attachment phase, this difference vanished as biofilm formation progressed. Our findings confirm that UV-photofunctionalization of titanium has a strong potential to improve outcome of implant placement by creating and maintaining antimicrobial surfaces. PMID:26210175

  3. Surface physical chemistry properties in coated bacterial cellulose membranes with calcium phosphate.

    Science.gov (United States)

    de Olyveira, Gabriel Molina; Basmaji, Pierre; Costa, Ligia Maria Manzine; Dos Santos, Márcio Luiz; Dos Santos Riccardi, Carla; Guastaldi, Fernando Pozzi Semeghini; Scarel-Caminaga, Raquel Mantuaneli; de Oliveira Capote, Ticiana Sidorenko; Pizoni, Elisabeth; Guastaldi, Antônio Carlos

    2017-06-01

    Bacterial cellulose has become established as a new biomaterial, and it can be used for medical applications. In addition, it has called attention due to the increasing interest in tissue engineering materials for wound care. In this work, the bacterial cellulose fermentation process was modified by the addition of chondroitin sulfate to the culture medium before the inoculation of the bacteria. The biomimetic process with heterogeneous calcium phosphate precipitation of biological interest was studied for the guided regeneration purposes on bacterial cellulose. FTIR results showed the incorporation of the chondroitin sulfate in the bacterial cellulose, SEM images confirmed the deposition of the calcium phosphate on the bacterial cellulose surface, XPS analysis showed a selective chemical group influences which change calcium phosphate deposition, besides, the calcium phosphate phase with different Ca/P ratios on bacterial cellulose surface influences wettability. XTT results concluded that these materials did not affect significantly in the cell viability, being non-cytotoxic. Thus, it was produced one biomaterial with the surface charge changes for calcium phosphate deposition, besides different wettability which builds new membranes for Guided Tissue Regeneration. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Abutment Coating With Diamond-Like Carbon Films to Reduce Implant-Abutment Bacterial Leakage.

    Science.gov (United States)

    Cardoso, Mayra; Sangalli, Jorgiana; Koga-Ito, Cristiane Yumi; Ferreira, Leandro Lameirão; da Silva Sobrinho, Argemiro Soares; Nogueira, Lafayette

    2016-02-01

    The influence of diamond-like carbon (DLC) films on bacterial leakage through the interface between abutments and dental implants of external hexagon (EH) and internal hexagon (IH) designs was evaluated. Film deposition was performed by plasma-enhanced chemical vapor deposition. Sets of implants and abutments (n = 30 per group, sets of 180 implants) were divided according to connection design and treatment of the abutment base: 1) no treatment (control); 2) DLC film deposition; and 3) Ag-DLC film deposition. Under sterile conditions, 1 μL Enterococcus faecalis was inoculated inside the implants, and abutments were tightened. The sets were tested for immediate external contamination, suspended in test tubes containing sterile culture broth, and followed for 5 days. Turbidity of the broth indicated bacterial leakage. At the end of the period, the abutments were removed and the internal content of the implants was collected with paper points and plated in Petri dishes. After 24-hour incubation, they were assessed for bacterial viability and colony-forming unit counting. Bacterial leakage was analyzed by χ(2) and Fisher exact tests (α = 5%). The percentage of bacterial leakage was 16.09% for EH implants and 80.71% for IH implants (P DLC and Ag-DLC films do not significantly reduce the frequency of bacterial leakage and bacteria load inside the implants.

  5. Bacterial growth on macrophyte leachate and fate of bacterial production

    International Nuclear Information System (INIS)

    Findlay, S.; Carlough, L.; Crocker, M.T.; Gill, H.K.; Meyer, J.L.; Smith, P.J.

    1986-01-01

    The role bacteria play in transferring organic carbon to other trophic levels in aquatic ecosystems depends on the efficiency with which they convert dissolved organic [ 14 C]-labelled carbon into bacterial biomass and on the ability of consumers to graze bacteria. The authors have measured the conversion efficiency for bacteria growing on macrophyte-derived dissolved organic carbon and estimated the amount of bacterial production removed by grazing. Bacteria converted this DOC into new tissue with an efficiency of 53%, substantially higher than the apparent conversion efficiency of macrophyte-derived particulate organic carbon or other types of DOC. Two estimates of grazing indicate that the decline in bacterial numbers after the bloom was probably due to grazing by flagellates. These results show the significance of the bacterial link between DOC and other trophic levels

  6. Bacterial cellulose and bacterial cellulose-vaccarin membranes for wound healing

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Yuyu [Key Laboratory of Eco-textiles, Jiangnan University, Wuxi (China); Laboratory of Natural Medicine, Wuxi Medical School, Jiangnan University (China); Qiu, Liying [Laboratory of Natural Medicine, Wuxi Medical School, Jiangnan University (China); Cui, Jing [Key Laboratory of Eco-textiles, Jiangnan University, Wuxi (China); Wei, Qufu, E-mail: qfwei@jiangnan.edu.cn [Key Laboratory of Eco-textiles, Jiangnan University, Wuxi (China)

    2016-02-01

    Bacterial cellulose (BC) and bacterial cellulose-vaccarin (BC-Vac) membranes were successfully produced in large scale. BC was synthesized by Gluconacetobacter xylinum. BC-Vac membranes were prepared by immersing BC in vaccarin solution. The surface morphologies of BC and BC-Vac membranes were examined by a scanning electron microscope (SEM) and an atomic force microscopy (AFM). The images showed that BC-Vac exhibited the characteristic 3D nanofibrillar network of BC matrix but there was adhesion between fibers. The mechanical properties of BC and BC-Vac membranes were evaluated and the results indicated that the adding of drug vaccarin into the BC membranes increased the malleability indicated by the increment in elongation at break compared with BC. Fourier transform infrared spectroscopy (FTIR) analysis was conducted to confirm the incorporation of vaccarin in BC-Vac and investigate the hydroxyl interactions between BC and drug vaccarin. Cell viability and cell attachment studies demonstrated that BC and BC-Vac membranes had no cytotoxicity and could be a good carrier for cell growth. The wound healing performance was examined in vivo by rat skin models. Histological observations revealed that wounds treated with BC-Vac epithelialized and regenerated faster than treated with BC. Therefore, BC-Vac was considered as a potential candidate for wound dressing materials. - Highlights: • BC and BC-Vac membranes were produced to achieve desirable properties. • BC and BC-Vac membranes could be a good carrier for cell growth. • BC-Vac membranes have potential application for wound healing.

  7. Sustainable model for financial viability of decentralized biomass gasifier based power projects

    NARCIS (Netherlands)

    Palit, D.; Malhotra, R.; Kumar, Atul

    2011-01-01

    This paper made a modest attempt for designing a sustainable model for financial viability of biomass gasifier power projects for enhancing electricity access in India and other developing countries. For long term sustainability of distributed generation projects in remote rural areas, viability

  8. Effect of storage time on the viability of cryopreserved bovine spermatozoa

    Science.gov (United States)

    Long term cryopreserved semen viability can impact the National Animal Germplasm Program’s (NAGP) sampling strategy and ability to reconstitute livestock populations. Therefore, the purpose of this project was to determine if prolonged storage of cryopreserved sperm impacts cell viability. Cryoprese...

  9. Linking population viability, habitat suitability, and landscape simulation models for conservation planning

    Science.gov (United States)

    Michael A. Larson; Frank R., III Thompson; Joshua J. Millspaugh; William D. Dijak; Stephen R. Shifley

    2004-01-01

    Methods for habitat modeling based on landscape simulations and population viability modeling based on habitat quality are well developed, but no published study of which we are aware has effectively joined them in a single, comprehensive analysis. We demonstrate the application of a population viability model for ovenbirds (Seiurus aurocapillus)...

  10. Studies on the viability of perspex as a window material in high radiation field

    International Nuclear Information System (INIS)

    Tripathi, S.C.; Ramanujam, A.

    1998-01-01

    Hot cells meant for handling high radioactivity essentially require proper transparent material in front of lead viewing windows. Inherent demerits of glass like frigility and radiation induced darkening has prompted us to evaluate the viability of commercially available perspex sheets glass. The study of optical absorbance, impact and tensile strengths as a function of absorbed dose indicates its viability. (author)

  11. Teaching recovery to medical students.

    LENUS (Irish Health Repository)

    Feeney, Larkin

    2013-03-01

    Community mental health services are evolving toward more holistic, patient-centered, recovery-based practices. This change necessitates an attitudinal shift from mental health workers, and training in recovery principles is helpful in achieving this change. Medical students often have narrow, doctor-centered concepts of mental health care. Traditional clinical placements in psychiatry do little to address this. We evaluated a recovery-focused teaching program for medical students in psychiatry.

  12. Gut dysbiosis impairs recovery after spinal cord injury.

    Science.gov (United States)

    Kigerl, Kristina A; Hall, Jodie C E; Wang, Lingling; Mo, Xiaokui; Yu, Zhongtang; Popovich, Phillip G

    2016-11-14

    The trillions of microbes that exist in the gastrointestinal tract have emerged as pivotal regulators of mammalian development and physiology. Disruption of this gut microbiome, a process known as dysbiosis, causes or exacerbates various diseases, but whether gut dysbiosis affects recovery of neurological function or lesion pathology after traumatic spinal cord injury (SCI) is unknown. Data in this study show that SCI increases intestinal permeability and bacterial translocation from the gut. These changes are associated with immune cell activation in gut-associated lymphoid tissues (GALTs) and significant changes in the composition of both major and minor gut bacterial taxa. Postinjury changes in gut microbiota persist for at least one month and predict the magnitude of locomotor impairment. Experimental induction of gut dysbiosis in naive mice before SCI (e.g., via oral delivery of broad-spectrum antibiotics) exacerbates neurological impairment and spinal cord pathology after SCI. Conversely, feeding SCI mice commercial probiotics (VSL#3) enriched with lactic acid-producing bacteria triggers a protective immune response in GALTs and confers neuroprotection with improved locomotor recovery. Our data reveal a previously unknown role for the gut microbiota in influencing recovery of neurological function and neuropathology after SCI. © 2016 Kigerl et al.

  13. Adjunctive Therapies for Bacterial Keratitis.

    Science.gov (United States)

    Dakhil, Turki Abdulaziz Bin; Stone, Donald U; Gritz, David C

    2017-01-01

    Bacterial keratitis is the most common type among all types of infectious keratitis. Currently, antibiotics are the main-stay of treatment. The objective of this systematic review is to review published clinical studies which discuss the adjunctive treatment of bacterial keratitis to guide clinical decision-making. We reviewed the role of a variety of medications and surgeries which can help in managing bacterial keratitis complications, which include as thinning, perforation, and impaired wound healing. We have included appropriate animal and laboratory studies, case reports and case series, and randomized clinical trials regarding each therapy.

  14. Blue light (470 nm) effectively inhibits bacterial and fungal growth.

    Science.gov (United States)

    De Lucca, A J; Carter-Wientjes, C; Williams, K A; Bhatnagar, D

    2012-12-01

    Blue light (470 nm) LED antimicrobial properties were studied alone against bacteria and with or without the food grade photosensitizer, erythrosine (ERY) against filamentous fungi. Leuconostoc mesenteroides (LM), Bacillus atrophaeus (BA) or Pseudomonas aeruginosa (PA) aliquots were exposed on nutrient agar plates to Array 1 (AR1, 0·2 mW cm(-2)) or Array 2 (AR2, 80 mW cm(-2)), which emitted impure or pure blue light (0-300 J cm(-2)), respectively. Inoculated control (room light only) plates were incubated (48 h) and colonies enumerated. The antifungal properties of blue light combined with ERY (11·4 and 22·8 μmol l(-1)) on Penicillium digitatum (PD) and Fusarium graminearum (FG) conidia were determined. Conidial controls consisted of: no light, room light-treated conidia and ERY plus room light. Light-treated (ERY + blue light) conidial samples were exposed only to AR2 (0-100 J cm(-2)), aliquots spread on potato dextrose agar plates, incubated (48 h, 30°C) and colonies counted. Blue light alone significantly reduced bacterial and FG viability. Combined with ERY, it significantly reduced PD viability. Blue light is lethal to bacteria and filamentous fungi although effectiveness is dependent on light purity, energy levels and microbial genus. Light from two arrays of different blue LEDs significantly reduced bacterial (Leuconostoc mesenteroides, Bacillus atrophaeus and Pseudomonas aeruginosa) viabilities. Significant in vitro viability loss was observed for the filamentous fungi, Penicillium digitatum and Fusarium graminearum when exposed to pure blue light only plus a photosensitizer. F. graminearum viability was significantly reduced by blue light alone. Results suggest that (i) the amount of significant loss in bacterial viability observed for blue light that is pure or with traces of other wavelengths is genus dependent and (ii) depending on fungal genera, pure blue light is fungicidal with or without a photosensitizer. © 2012 The Society for

  15. The effect of bacterial cellulose on the shape memory behavior of polyvinyl alcohol nanocomposite hydrogel

    Science.gov (United States)

    Pirahmadi, Pegah; Kokabi, Mehrdad

    2018-01-01

    Most research on shape memory polymers has been confined to neat polymers in their dry state, while, some hydrogel networks are known for their shape memory properties. Hydrogels have low glass transition temperatures which are below 100°C depend on the content of water. But they are usually weak and brittle, and not suitable for structural applications due to their low mechanical strengths because of these materials have large amount of water (>50%), so they could not remember original shape perfectly. Bacterial cellulose nanofibers with perfect properties such as high water holding capacity, high crystallinity, high tensile strength and good biocompatibility can dismiss all the drawbacks. In the present study, polyvinyl alcohol/bacterial cellulose nanocomposite hydrogel prepared by repetitive freezing-thawing method. The bacterial cellulose was used as reinforcement to improve the mechanical properties and stimuli response. Differential scanning calorimetry was employed to obtain the glass transition temperature. Nanocomposite morphology was characterized by field-emission scanning electron microscopy and mechanical properties were investigated by standard tensile test. Finally, the effect of bacterial cellulose nanofiber on shape memory behavior of polyvinyl alcohol/bacterial cellulose nanocomposite hydrogel was investigated. It is found that switching temperature of this system is the glass transition temperature of the nano domains formed within the system. The results also show increase of shape recovery, and shape recovery speed due to presence of bacterial cellulose.

  16. Molecular detection of human bacterial pathogens

    National Research Council Canada - National Science Library

    Liu, Dongyou

    2011-01-01

    .... Molecular Detection of Human Bacterial Pathogens addresses this issue, with international scientists in respective bacterial pathogen research and diagnosis providing expert summaries on current...

  17. Viability, Acid and Bile Tolerance of Spray Dried Probiotic Bacteria and Some Commercial Probiotic Supplement Products Kept at Room Temperature.

    Science.gov (United States)

    Dianawati, Dianawati; Mishra, Vijay; Shah, Nagendra P

    2016-06-01

    Production of probiotic food supplements that are shelf-stable at room temperature has been developed for consumer's convenience, but information on the stability in acid and bile environment is still scarce. Viability and acid and bile tolerance of microencapsulated Bifidobacterium spp. and Lactobacillus acidophilus and 4 commercial probiotic supplements were evaluated. Bifidobacterium and L. acidophilus were encapsulated with casein-based emulsion using spray drying. Water activity (aw ) of the microspheres containing Bifidobacterium or L. acidophilus (SD GM product) was adjusted to 0.07 followed by storage at 25 °C for 10 wk. Encapsulated Bifidobacterium spp. and Lactobacillus acidophilus and 4 commercial probiotic supplement products (AL, GH, RE, and BM) were tested. Since commercial probiotic products contained mixed bacteria, selective media MRS-LP (containing L-cysteine and Na-propionate) and MRS-clindamycin agar were used to grow Bifidobacterium spp. or L. acidophilus, respectively, and to inhibit the growth of other strains. The results showed that aw had a strong negative correlation with the viability of dehydrated probiotics of the 6 products. Viable counts of Bifidobacterium spp. and L. acidophilus of SD GM, AL, and GH were between 8.3 and 9.2 log CFU/g, whereas that of BM and RE were between 6.7 and 7.3 log CFU/g. Bifidobacterium in SD GM, in AL, and in GH products and L. acidophilus in SD GM, in AL, and in BM products demonstrated high tolerance to acid. Most of dehydrated probiotic bacteria were able to survive in bile environment except L. acidophilus in RE product. Exposure to gastric juice influenced bacterial survivability in subsequent bile environment. © 2016 Institute of Food Technologists®

  18. Business recovery: an assessment framework.

    Science.gov (United States)

    Stevenson, Joanne R; Brown, Charlotte; Seville, Erica; Vargo, John

    2017-11-06

    This paper presents a Business Recovery Assessment Framework (BRAF) to help researchers and practitioners design robust, repeatable, and comparable studies of business recovery in various post-disruption contexts. Studies assessing business recovery without adequately considering the research aims, recovery definitions, and indicators can produce misleading findings. The BRAF is composed of a series of steps that guide the decisions that researchers need to make to ensure: (i) that recovery is indeed being measured; (ii) that the indicators of recovery that are selected align with the objectives of the study and the definition of recovery; and, where necessary, (iii) that appropriate comparative control variables are in place. The paper draws on a large dataset of business surveys collected following the earthquakes in Canterbury, New Zealand, on 4 September 2010 and 22 February 2011 to demonstrate the varied conclusions that different recovery indicators can produce and to justify the need for a systematic approach to business recovery assessments. © 2017 The Author(s). Disasters © Overseas Development Institute, 2017.

  19. BACTERIAL LEACHING OF ELECTRONIC SCRAP: INFLUENCE OF PROCESS PARAMETERS

    Directory of Open Access Journals (Sweden)

    Luciana Harue Yamane

    2013-03-01

    Full Text Available The application of bacterial leaching in the ore treatment is already known and also can be applied such as treatment of electronic waste to copper recovery. This paper investigates the influence of process parameters (pulp density, inoculums volume, rotation speed and initial concentration of ferrous iron on bacterial leaching of copper from printed circuit board of computers using the bacterium Acidithiobacillus ferrooxidans–LR. Printed circuit boards from computers were comminuted using a hammer mill. The powder obtained was magnetically separated and the non-magnetic material used in this study. A shake flask study was carried out on the non-magnetic material using a shaker. The results show that Acidithiobacillus ferrooxidans–LR can leach 99% of copper from printed circuit boards (non–magnetic material under the determined conditions through of the studies.

  20. Interlaced CNT Electrodes for Bacterial Fouling Reduction of Microfiltration Membranes.

    Science.gov (United States)

    Zhang, Qiaoying; Arribas, Paula; Remillard, E Marielle; García-Payo, M Carmen; Khayet, Mohamed; Vecitis, Chad D

    2017-08-15

    Interlaced carbon nanotube electrodes (ICE) were prepared by vacuum filtering a well-dispersed carbon nanotube-Nafion solution through a laser-cut acrylic stencil onto a commercial polyvinylidene fluoride (PVDF) microfiltration (MF) membrane. Dead-end filtration was carried out using 10 7 and 10 8 CFU mL -1 Pseudomonas fluorescens to study the effects of the electrochemically active ICE on bacterial density and morphology, as well as to evaluate the bacterial fouling trend and backwash (BW) efficacy, respectively. Finally, a simplified COMSOL model of the ICE electric field was used to help elucidate the antifouling mechanism in solution. At 2 V DC and AC (total cell potential), the average bacterial log removal of the ICE-PVDF increased by ∼1 log compared to the control PVDF (3.5-4 log). Bacterial surface density was affected by the presence and polarity of DC electric potential, being 87-90% lower on the ICE cathode and 59-93% lower on the ICE anode than that on the PVDF after filtration, and BW further reduced the density on the cathode significantly. The optimal operating conditions (2 V AC) reduced the fouling rate by 75% versus the control and achieved up to 96% fouling resistance recovery (FRR) during BW at 8 V AC using 155 mM NaCl. The antifouling performance should mainly be due to electrokinetic effects, and the electric field simulation by COMSOL model suggested electrophoresis and dielectrophoresis as likely mechanisms.

  1. COST IMPACT OF ROD CONSOLIDATION ON THE VIABILITY ASSESSMENT DESIGN

    Energy Technology Data Exchange (ETDEWEB)

    D. Lancaster

    1999-03-29

    The cost impact to the Civilian Radioactive Waste Management System of using rod consolidation is evaluated. Previous work has demonstrated that the fuel rods of two assemblies can be packed into a canister that can fit into the same size space as that used to store a single assembly. The remaining fuel assembly hardware can be compacted into the same size canisters with a ratio of 1 hardware canister per each 6 to 12 assemblies. Transportation casks of the same size as currently available can load twice the number of assemblies by placing the compacted assemblies in the slots currently designed for a single assembly. Waste packages similarly could contain twice the number of assemblies; however, thermal constraints would require considering either a low burnup or cooling. The analysis evaluates the impact of rod consolidation on CRWMS costs for consolidation at prior to transportation and for consolidation at the Monitored Geological Repository surface facility. For this study, no design changes were made to either the transport casks or waste packages. Waste package designs used for the Viability Assessment design were employed but derated to make the thermal limits. A logistics analysis of the waste was performed to determine the number of each waste package with each loading. A review of past rod consolidation experience found cost estimates which range from $10/kgU to $32/kgU. $30/kgU was assumed for rod consolidation costs prior to transportation. Transportation cost savings are about $17/kgU and waste package cost savings are about $21/kgU. The net saving to the system is approximately $500 million if the consolidation is performed prior to transportation. If consolidation were performed at the repository surface facilities, it would cost approximately $15/kgU. No transportation savings would be realized. The net savings for consolidation at the repository site would be about $400 million dollars.

  2. Detection and viability of Lactococcus lactis throughout cheese ripening.

    Directory of Open Access Journals (Sweden)

    Marianna Ruggirello

    Full Text Available Recent evidences highlighted the presence of Lactococcus lactis during late cheese ripening. For this reason, the role of this microorganism, well known as dairy starter, should be reconsidered throughout cheese manufacturing and ripening. Thus, the main objective of this study was to develop a RT-qPCR protocol for the detection, quantification and determination of the viability of L. lactis in ripened cheese samples by direct analysis of microbial nucleic acids. Standard curves were constructed for the specific quantification of L. lactis in cheese matrices and good results in terms of selectivity, correlation coefficient and efficiency were obtained. Thirty-three ripened cheeses were analyzed and, on the basis of RNA analysis, twelve samples showed 106 to 108 CFU of L. lactis per gram of product, thirteen from 103 to 105 CFU/g, and in eight cheeses, L. lactis was not detected. Traditional plating on M17 medium led to loads ranging from 105 to 109 CFU/g, including the cheese samples where no L. lactis was found by RT-qPCR. From these cheeses, none of the colonies isolated on M17 medium was identified as L. lactis species. These data could be interpreted as a lack of selectivity of M17 medium where colony growth is not always related to lactococcal species. At the same time, the absence or low abundance of L. lactis isolates on M17 medium from cheese where L. lactis was detected by RT-qPCR support the hypothesis that L. lactis starter populations are mainly present in viable but not culturable state during ripening and, for this reason, culture-dependent methods have to be supplemented with direct analysis of cheese.

  3. Detection and Viability of Lactococcus lactis throughout Cheese Ripening

    Science.gov (United States)

    Cocolin, Luca

    2014-01-01

    Recent evidences highlighted the presence of Lactococcus lactis during late cheese ripening. For this reason, the role of this microorganism, well known as dairy starter, should be reconsidered throughout cheese manufacturing and ripening. Thus, the main objective of this study was to develop a RT-qPCR protocol for the detection, quantification and determination of the viability of L. lactis in ripened cheese samples by direct analysis of microbial nucleic acids. Standard curves were constructed for the specific quantification of L. lactis in cheese matrices and good results in terms of selectivity, correlation coefficient and efficiency were obtained. Thirty-three ripened cheeses were analyzed and, on the basis of RNA analysis, twelve samples showed 106 to 108 CFU of L. lactis per gram of product, thirteen from 103 to 105 CFU/g, and in eight cheeses, L. lactis was not detected. Traditional plating on M17 medium led to loads ranging from 105 to 109 CFU/g, including the cheese samples where no L. lactis was found by RT-qPCR. From these cheeses, none of the colonies isolated on M17 medium was identified as L. lactis species. These data could be interpreted as a lack of selectivity of M17 medium where colony growth is not always related to lactococcal species. At the same time, the absence or low abundance of L. lactis isolates on M17 medium from cheese where L. lactis was detected by RT-qPCR support the hypothesis that L. lactis starter populations are mainly present in viable but not culturable state during ripening and, for this reason, culture-dependent methods have to be supplemented with direct analysis of cheese. PMID:25503474

  4. Assessment of donor heart viability during ex vivo heart perfusion.

    Science.gov (United States)

    White, Christopher W; Ambrose, Emma; Müller, Alison; Li, Yun; Le, Hoa; Hiebert, Brett; Arora, Rakesh; Lee, Trevor W; Dixon, Ian; Tian, Ganghong; Nagendran, Jayan; Hryshko, Larry; Freed, Darren

    2015-10-01

    Ex vivo heart perfusion (EVHP) may facilitate resuscitation of discarded donor hearts and expand the donor pool; however, a reliable means of demonstrating organ viability prior to transplantation is required. Therefore, we sought to identify metabolic and functional parameters that predict myocardial performance during EVHP. To evaluate the parameters over a broad spectrum of organ function, we obtained hearts from 9 normal pigs and 37 donation after circulatory death pigs and perfused them ex vivo. Functional parameters obtained from a left ventricular conductance catheter, oxygen consumption, coronary vascular resistance, and lactate concentration were measured, and linear regression analyses were performed to identify which parameters best correlated with myocardial performance (cardiac index: mL·min(-1)·g(-1)). Functional parameters exhibited excellent correlation with myocardial performance and demonstrated high sensitivity and specificity for identifying hearts at risk of poor post-transplant function (ejection fraction: R(2) = 0.80, sensitivity = 1.00, specificity = 0.85; stroke work: R(2) = 0.76, sensitivity = 1.00, specificity = 0.77; minimum dP/dt: R(2) = 0.74, sensitivity = 1.00, specificity = 0.54; tau: R(2) = 0.51, sensitivity = 1.00, specificity = 0.92), whereas metabolic parameters were limited in their ability to predict myocardial performance (oxygen consumption: R(2) = 0.28; coronary vascular resistance: R(2) = 0.20; lactate concentration: R(2) = 0.02). We concluded that evaluation of functional parameters provides the best assessment of myocardial performance during EVHP, which highlights the need for an EVHP device capable of assessing the donor heart in a physiologic working mode.

  5. Analysis of the competitive viability of independent middle distillate marketers

    Energy Technology Data Exchange (ETDEWEB)

    1979-11-01

    The viability of the home heating oil dealer is being threatened by changes in the basic conditions of the middle distillate industry. These changes, which were examined over the study period from 1972 through 1978, are summarized below. (1) The overall number of households using home heating oil for space conditioning has declined from 1970 to 1976. This pattern has occurred in an expanding market. The Northeast Census Region is the only area of the country in which the number of households using heating oil shows a net increase. (2) The quantity of home heating oil consumed by the residential sector has declined by 8.3 percent between 1972 and 1977. (3) The average level of consumption per household has declined 5.9 percent from 1970 to 1976. (4) Demand for distillate fuel oil as diesel fuel for on- and off-highway use; for industrial and oil company consumption; for vessels, railroads, and all other uses, has increased 14.5 percent. (5) Total refining capacity that is capable of producing middle distillates has increased 17 percent. (6) Total annual distillate output has increased 18 percent from 1974 through 1978. (7) Prices for home heating oil increased by more than 150 percent from 1972 to 1977, compared with 93 percent for the less expensive natural gas. Home heating oil dealers face a declining market, both in terms of number of households using the product and in terms of sales per household. Although total middle distillate supplies were adequate during the time period studied, the demand for distillate fuel oil for uses other than home heating oil may eventually put pressure on supplies. That is, downward pressure on prices, expected when supplies outstrip demand, may not occur because of the many alternative uses for home heating oil.

  6. Multispectral imaging of organ viability during uterine transplantation surgery

    Science.gov (United States)

    Clancy, Neil T.; Saso, Srdjan; Stoyanov, Danail; Sauvage, Vincent; Corless, David J.; Boyd, Michael; Noakes, David E.; Thum, Meen-Yau; Ghaem-Maghami, Sadaf; Smith, J. R.; Elson, Daniel S.

    2014-02-01

    Uterine transplantation surgery has been proposed as a treatment for permanent absolute uterine factor infertility (AUFI) in the case of loss of the uterus. Due to the complexity of the vasculature correct reanastomosis of the blood supply during transplantation surgery is a crucial step to ensure reperfusion and viability of the organ. While techniques such as fluorescent dye imaging have been proposed to visualise perfusion there is no gold standard for intraoperative visualisation of tissue oxygenation. In this paper results from a liquid crystal tuneable filter (LCTF)-based multispectral imaging (MSI) laparoscope are described. The system was used to monitor uterine oxygen saturation (SaO2) before and after transplantation. Results from surgeries on two animal models (rabbits and sheep) are presented. A feature-based registration algorithm was used to correct for misalignment induced by breathing or peristalsis in the tissues of interest prior to analysis. An absorption spectrum was calculated at each spatial pixel location using reflectance data from a reference standard, and the relative contributions from oxy- and deoxyhaemoglobin were calculated using a least squares regression algorithm with non-negativity constraints. Results acquired during animal surgeries show that cornual oxygenation changes are consistent with those observed in point measurements taken using a pulse oximeter, showing reduced SaO2 following reanastomosis. Values obtained using the MSI laparoscope were lower than those taken with the pulse oximeter, which may be due to the latter's use of the pulsatile arterial blood signal. Future work incorporating immunological test results will help to correlate SaO2 levels with surgical outcomes.

  7. Important population viability analysis parameters for giant pandas (Aliuropoda melanoleuca).

    Science.gov (United States)

    Gong, Minghao; Song, Yanling; Yang, Zhisong; Lin, Chen

    2012-06-01

    Population viability analysis (PVA) is a tool to evaluate the risk of extinction for endangered species and aid conservation decision-making. The quality of PVA output is dependent on parameters related to population dynamics and life-history; however, it has been difficult to collect this information for the giant panda (Aliuropoda melanoleuca), a rare and endangered mammal native to China, confined to some 30 fragmented habitat patches. Since giant pandas are long-lived, mature late, have lower reproductive rates, and show little sexual dimorphism, obtaining data to perform adequate PVA has been difficult. Here, we develop a parameter sensitivity index by modeling the dynamics of six giant panda populations in the Minshan Mountains, in order to determine the parameters most influential to giant panda populations. Our data shows that the giant panda populations are most sensitive to changes in four female parameters: initial breeding age, reproductive rate, mortality rate between age 0 and 1, and mortality rate of adults. The parameter sensitivity index strongly correlated with initial population size, as smaller populations were more sensitive to changes in these four variables. This model suggests that demographic parameters of females have more influence on the results of PVA, indicating that females may play a more important role in giant panda population dynamics than males. Consequently, reintroduction of female individuals to a small giant panda population should be a high priority for conservation efforts. Our findings form a technical basis for the coming program of giant panda reintroduction, and inform which parameters are crucial to successfully and feasibly monitoring wild giant panda populations.

  8. Radiation injuries and recovery

    International Nuclear Information System (INIS)

    Pauly, H.

    1974-01-01

    In memory of Prof. Dr. Langendorff, a survey and a cross-section are given of the development of radiobiology during the last 40 years. The importance of radiobiology is shown using several examples. The mechanisms and effects of radiation on man, animals and plants are discussed. Effects of radiation and radiolesious are explained down ot the molecular field, and their importance is discussed quantitatively with stochastic considerations. Stress is laid upon recovering from radiolesious. It is tried to explain recovery quantitatively in all its several sorts. Using all these deliberations, the author also tries to give a wide spectrum for radiation protection. These fundamental deliberations and works of Prof. Dr. Langendorff are guidelines of great importance also for radiation protection in connection with the protection of the civil population. (GSE) [de

  9. Waste heat recovery system

    Science.gov (United States)

    Ernst, Timothy C.; Zigan, James A.

    2017-12-19

    A waste heat recovery system includes a Rankine cycle (RC) circuit having a pump, a boiler, an energy converter, and a condenser fluidly coupled via conduits in that order, to provide additional work. The additional work is fed to an input of a gearbox assembly including a capacity for oil by mechanically coupling to the energy converter to a gear assembly. An interface is positioned between the RC circuit and the gearbox assembly to partially restrict movement of oil present in the gear assembly into the RC circuit and partially restrict movement of working fluid present in the RC circuit into the gear assembly. An oil return line is fluidly connected to at least one of the conduits fluidly coupling the RC components to one another and is operable to return to the gear assembly oil that has moved across the interface from the gear assembly to the RC circuit.

  10. Speech recovery device

    Energy Technology Data Exchange (ETDEWEB)

    Frankle, Christen M.

    2000-10-19

    There is provided an apparatus and method for assisting speech recovery in people with inability to speak due to aphasia, apraxia or another condition with similar effect. A hollow, rigid, thin-walled tube with semi-circular or semi-elliptical cut out shapes at each open end is positioned such that one end mates with the throat/voice box area of the neck of the assistor and the other end mates with the throat/voice box area of the assisted. The speaking person (assistor) makes sounds that produce standing wave vibrations at the same frequency in the vocal cords of the assisted person. Driving the assisted person's vocal cords with the assisted person being able to hear the correct tone enables the assisted person to speak by simply amplifying the vibration of membranes in their throat.

  11. Speech recovery device

    Energy Technology Data Exchange (ETDEWEB)

    Frankle, Christen M.

    2004-04-20

    There is provided an apparatus and method for assisting speech recovery in people with inability to speak due to aphasia, apraxia or another condition with similar effect. A hollow, rigid, thin-walled tube with semi-circular or semi-elliptical cut out shapes at each open end is positioned such that one end mates with the throat/voice box area of the neck of the assistor and the other end mates with the throat/voice box area of the assisted. The speaking person (assistor) makes sounds that produce standing wave vibrations at the same frequency in the vocal cords of the assisted person. Driving the assisted person's vocal cords with the assisted person being able to hear the correct tone enables the assisted person to speak by simply amplifying the vibration of membranes in their throat.

  12. Plant hydrocarbon recovery process

    Energy Technology Data Exchange (ETDEWEB)

    Dzadzic, P.M.; Price, M.C.; Shih, C.J.; Weil, T.A.

    1982-01-26

    A process for production and recovery of hydrocarbons from hydrocarbon-containing whole plants in a form suitable for use as chemical feedstocks or as hydrocarbon energy sources which process comprises: (A) pulverizing by grinding or chopping hydrocarbon-containing whole plants selected from the group consisting of euphorbiaceae, apocynaceae, asclepiadaceae, compositae, cactaceae and pinaceae families to a suitable particle size, (B) drying and preheating said particles in a reducing atmosphere under positive pressure (C) passing said particles through a thermal conversion zone containing a reducing atmosphere and with a residence time of 1 second to about 30 minutes at a temperature within the range of from about 200* C. To about 1000* C., (D) separately recovering the condensable vapors as liquids and the noncondensable gases in a condition suitable for use as chemical feedstocks or as hydrocarbon fuels.

  13. Ecological recovery in ERA

    DEFF Research Database (Denmark)

    EFSA Scientific Committee (Scientific Committee); Topping, Christopher John

    2016-01-01

    knowledge and data retrieved from the literature. Finally, the information presented in this opinion was reviewed by experts from the relevant EFSA Panels, European risk assessment bodies and through an open consultation requesting input from stakeholders. A conceptual framework was developed to address......EFSA performs environmental risk assessments (ERAs) for single potential stressors such as plant protection products, genetically modified organisms and feed additives and for invasive alien species that are harmful for plant health. In this risk assessment domain, the EFSA Scientific Committee...... recognises the importance of more integrated ERAs considering both the local and landscape scales, as well as the possible co-occurrence of multiple potential stressors that fall under the remit of EFSA, which are important when addressing ecological recovery. In this scientific opinion, the Scientific...

  14. Planning tiger recovery

    DEFF Research Database (Denmark)

    Wilting, Andreas; Courtiol, Alexandre; Christiansen, Per

    2015-01-01

    two subspecies: the Sunda tiger, Panthera tigris sondaica, and the continental tiger, Panthera tigris tigris, which consists of two (northern and southern) management units. Conservation management programs, such as captive breeding, reintroduction initiatives, or trans-boundary projects, rely......Although significantly more money is spent on the conservation of tigers than on any other threatened species, today only 3200 to 3600 tigers roam the forests of Asia, occupying only 7% of their historical range. Despite the global significance of and interest in tiger conservation, global...... approaches to plan tiger recovery are partly impeded by the lack of a consensus on the number of tiger subspecies or management units, because a comprehensive analysis of tiger variation is lacking. We analyzed variation among all nine putative tiger subspecies, using extensive data sets of several traits...

  15. Evaluation of ischemic heart disease and viability by cardiac MRI

    Directory of Open Access Journals (Sweden)

    Mona Bhatia

    2014-01-01

    Full Text Available In ischemic heart disease, cardiac MRI, besides being the gold standard for evaluation of quantitative ventricular function, enables evaluation of myocardial wall thickness, T2-weighted imaging for myocardial edema and infarct quantification and transmurality. Delayed hyperenhancement sequences are highly predictive of scar formation, being associated with myocyte necrosis. The extent and transmurality of delayed hyperenhancement has prognostic implications and is inversely proportional to the degree of functional recovery after acute myocardial infarction. A greater transmural extent of infarction (eg, hyperenhancement involving >50% of the wall thickness can predict regions that are less likely to improve in function after therapy. The ultimate focus of MRI in ischemic heart disease is in diagnosis, quantification of myocardium at risk, salvageable myocardium, perfusion defects and differentiation of viable myocardium from non viable myocardium to enable prognostication.

  16. Bacterial sepsis and chemokines.

    Science.gov (United States)

    Kobayashi, Makiko; Tsuda, Yasuhiro; Yoshida, Tsuyoshi; Takeuchi, Dan; Utsunomiya, Tokuichiro; Takahashi, Hitoshi; Suzuki, Fujio

    2006-01-01

    Bacterial sepsis causes a high mortality rate when it occurs in patients with compromised host defenses. Severely burned patients, typical immunocompromised hosts, are extremely susceptible to infections from various pathogens, and a local wound infection frequently escalates into sepsis. In these patients, Staphylococcus aureus, Enterococcus faecalis and Pseudomonas aeruginosa are familiar pathogens that cause opportunistic infections. Also, polymicrobial sepsis frequently occurs in these patients. In this review, therefore, the roles of chemokines in thermally injured patients infected with these 3 pathogens and polymicrobial sepsis will be discussed. These infections in thermally injured patients may be controlled immunologically, because immunocompetent hosts are resistant to infections with these pathogens. Classically activated macrophages (M1Mphi) are major effector cells for host innate immune responses against these infections. However, M1Mphi are not generated in thermally injured patients whose alternatively activated macrophages (M2Mphi) predominate. M2Mphi appear in patients early after severe burn injuries. M2Mphi inhibit M1Mphi generation through the secretion of CCL17 and IL-10. As a modulator of Mphi, two different subsets of neutrophils (PMN-I, PMN-II) are described. PMN-I direct the polarization of resident Mphi into M1Mphi through the production of CCL3. M2Mphi are induced from resident Mphi by CCL2 released from PMN-II. Therefore, as an inhibitor of CCL2, glycyrrhizin protects individuals infected with S. aureus. Sepsis stemming from P. aeruginosa wound infection is also influenced by CCL2 released from immature myeloid cells. A large number of immature myeloid cells appear in association with burn injuries. Host resistance to S. aureus, E. faecalis, P. aeruginosa or polymicrobial infections may be improved in thermally injured patients through the induction of M1Mphi, elimination of CCL2 and/or depletion of M2Mphi induced by CCL2.

  17. Bacterial Communities: Interactions to Scale

    Directory of Open Access Journals (Sweden)

    Reed M. Stubbendieck

    2016-08-01

    Full Text Available In the environment, bacteria live in complex multispecies communities. These communities span in scale from small, multicellular aggregates to billions or trillions of cells within the gastrointestinal tract of animals. The dynamics of bacterial communities are determined by pairwise interactions that occur between different species in the community. Though interactions occur between a few cells at a time, the outcomes of these interchanges have ramifications that ripple through many orders of magnitude, and ultimately affect the macroscopic world including the health of host organisms. In this review we cover how bacterial competition influences the structures of bacterial communities. We also emphasize methods and insights garnered from culture-dependent pairwise interaction studies, metagenomic analyses, and modeling experiments. Finally, we argue that the integration of multiple approaches will be instrumental to future understanding of the underlying dynamics of bacterial communities.

  18. Bacterial flora of sturgeon fingerling

    International Nuclear Information System (INIS)

    Arani, A.S.; Mosahab, R.

    2008-01-01

    The study on microbial populations is a suitable tool to understand and apply control methods to improve the sanitary level of production in fish breeding and rearing centers, ensure health of sturgeon fingerlings at the time of their release into the rivers and also in the conversation and restoration of these valuable stocks in the Caspian Sea, Iran. A laboratory research based on Austin methods (Austin, B., Austin, D.A. 1993) was conducted for bacterial study on 3 sturgeon species naming A. persicus, A. stellatus and A. nudiventris during different growth stages. Bacterial flora of Acinetobacter, Moraxella, Aeromonas, Vibrio, Edwardsiella, Staphylococcus, Proteus, Yersinia, Pseudomonas and Plesiomonas were determined. The factors which may induce changes in bacterial populations during different stages of fife are the followings: quality of water in rearing ponds, different conditions for growth stages, suitable time for colonization of bacterial flora in rearing pond, water temperature increase in fingerlings size and feeding condition. (author)

  19. Subdural Empyema in Bacterial Meningitis

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2013-01-01

    Full Text Available Researchers at the University of Amsterdam, the Netherlands, evaluated the occurrence, treatment, and outcome of subdural empyema as a complication of community-acquired bacterial meningitis in 28 (2.7% adults.

  20. Influence of prior growth conditions, pressure treatment parameters, and recovery conditions on the inactivation and recovery of Listeria monocytogenes, Escherichia coli, and Salmonella Typhimurium in turkey meat.

    Science.gov (United States)

    Juck, Greg; Neetoo, Hudaa; Beswick, Ethan; Chen, Haiqiang

    2012-02-01

    The relatively high prevalence of Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella enterica serovar Typhimurium in various food products is of great concern to the food industry. The objective of this study was to determine the pressure-inactivation of the pathogens in a representative food model as affected by prior growth temperature, physiological age of the culture, pressure level and treatment temperature. The effect of post-treatment conditions (incubation temperature and gas atmosphere) on the bacterial recovery was also determined. The pathogens being studied were inoculated into sterile turkey breast meat to a final level of ca. 3 logCFU/g and then grown to two stages, the early stage (representative of exponential phase) and late stage (representative of stationary phase), at 15, 25, 35, and 40 °C. Turkey meat samples were pressure-treated at 400 and 600 MPa for 2 min at initial sample temperatures of 4, 20 and 40 °C. Following treatment, bacterial counts in the samples were determined aerobically or anaerobically at incubation temperatures of 15, 25, 35, and 40 °C. Pressure inactivation of the bacterial pathogens increased as a function of the pressure levels and treatment temperatures. Generally speaking, early stage cells were more resistant than late stage cells (P<0.05). The incubation gas atmosphere did not affect bacterial recovery. Bacteria grown at 15-35 °C underwent higher population reductions than those grown at 40 °C. With regard to recovery temperatures, low temperatures promoted greater recovery of injured early and late stage cells than higher temperatures (P<0.05). This study indicates the importance of environmental conditions to which bacteria are exposed prior to pressure treatment and recovery conditions of the bacteria after pressure treatment when considering the adequacy of pressure treatments to enhance the microbiological safety of foods. Copyright © 2011 Elsevier B.V. All rights reserved.