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Sample records for agar medium supplemented

  1. An improved agar medium for growth of Geobacillus thermoglucosidarius strains.

    PubMed

    Javed, M; Baghaei-Yazdi, N; Qin, W; Amartey, S

    2017-01-01

    Geobacillus species have potential applications in many biotechnological processes. They are fastidious in their vitamin and amino acid requirements. A new semi-defined agar medium (SDM) was developed which gave consistently high viable cell counts of various G. thermoglucosidasius strains (5×10(8)-6×10(8)cfu/ml) under aerobic conditions at 70°C.

  2. A supplemented soft agar chemotaxis assay demonstrates the Helicobacter pylori chemotactic response to zinc and nickel

    PubMed Central

    Sanders, Lisa; Andermann, Tessa M.

    2013-01-01

    Directed motility, or chemotaxis, is required for Helicobacter pylori to establish infection in the stomach, although the full repertoire of this bacterium’s chemotactic responses is not yet known. Here we report that H. pylori responds to zinc as an attractant and nickel as a repellent. To reach this conclusion, we employed both a temporal chemotaxis assay based on bacterial reversals and a supplemented soft agar spatial assay. We refined the temporal assay using a previously described chemorepellent, acid, and found that H. pylori requires rich media with serum to maintain optimal swimming motility. Surprisingly, we found that some strains respond to acid as an attractant, and that the TlpC chemoreceptor correlated with whether acid was sensed as an attractant or repellent. Using this same assay, we detected weak repellent responses to nickel and copper, and a varied response to zinc. We thus developed an alternative spatial chemotactic assay called the supplemented soft agar assay, which utilizes soft agar medium supplemented with the test compound. With Escherichia coli, the attractant serine slowed overall bacterial migration, while the repellent nickel increased the speed of overall migration. In H. pylori we detected slowed migration with doubled tryptone media, as well as zinc, consistent with an attractant response. In contrast, nickel increased migration, consistent with repulsion. PMID:23139399

  3. [Evaluation of a new medium, eggplant (Solanum melongena) agar as a screening medium for Cryptococcus neoformans in environmental samples].

    PubMed

    Sengul, Mustafa; Ergin, Cağrı; Kartal, Tuğba

    2014-04-01

    Cryptococcus neofomans is an encapsulated yeast-like fungus that causes life-threatening infections, especially in immunosuppresive patients. C.neoformans infection is believed to be acquired via inhalation of aerosolized particles from the environment. Avian guano, decaying tree hollows and soil are the related known environmental niches. Brown pigmented yeast growth from the precursors in growth media is an important step for the identification and isolation of C.neoformans. Seeds of plants in nature are preferred owing to easy accessibility and low costs for the preparation of such media. Guizotia abysinicca (Niger seed) as Staib agar, Helianthus annus (Sunflower) as Pal's medium, Brassica nigra (Mustard) agar, tobacco agar, Mucuna pruriens (Velvet bean) seed agar, Perilla frutescens (Beefsteak plant) seed agar, Rubus fruticosus (Blackberry) agar and ground red hot pepper agar are pigment-based selective media for the differentiation of C.neoformans. The aim of this study was to observe the pigment production of C.neoformans in a new medium based on eggplant (Solanum melongena) and also to compare its performance with the simplified Staib, Pal's and tobacco agar for isolation from the environment. Three different eggplant-based medium (S.melongena Melanzaza viserba, S.melongena Pinstripe F1 and S.ovigerum Ivory F1) were included in the study. Pigment-forming eggplant medium, simplified Staib agar, Pal's agar and tobacco agar were used for the cultivation of the environmental swabbed samples from 19 Eucalyptus camaldulensis trunk hollows in continuous colonization region. While pigment formation were observed with S.melongena Melanzaza viserba and S.melongena Pinstripe F1 containing media, S.ovigerum Ivory F1 medium was found to be non-reactive. In colonization area (Gökova-Akyaka, Turkey), 11 (57.9%) out of 19 E.camaldulensis samples were positive with simplified Staib agar, Pal's agar and eggplant agar while 10 (52.6%) of them are positive with tobacco agar. C

  4. Rapid Isolation and Susceptibility Testing of Leptospira spp. Using a New Solid Medium, LVW Agar

    PubMed Central

    Wuthiekanun, Vanaporn; Amornchai, Premjit; Paris, Daniel H.; Langla, Sayan; Thaipadunpanit, Janjira; Chierakul, Wirongrong; Smythe, Lee D.; White, Nicholas J.; Day, Nicholas P. J.; Peacock, Sharon J.

    2013-01-01

    Pathogenic Leptospira spp., the causative agents of leptospirosis, are slow-growing Gram-negative spirochetes. Isolation of Leptospira from clinical samples and testing of antimicrobial susceptibility are difficult and time-consuming. Here, we describe the development of a new solid medium that facilitates more-rapid growth of Leptospira spp. and the use of this medium to evaluate the Etest's performance in determining antimicrobial MICs to drugs in common use for leptospirosis. The medium was developed by evaluating the effects of numerous factors on the growth rate of Leptospira interrogans strain NR-20157. These included the type of base agar, the concentration of rabbit serum (RS), and the concentration and duration of CO2 incubation during the initial period of culture. The highest growth rate of NR-20157 was achieved using a Noble agar base supplemented with 10% RS (named LVW agar), with an initial incubation at 30°C in 5% CO2 for 2 days prior to continuous culture in air at 30°C. These conditions were used to develop the Etest for three species, L. interrogans (NR-20161), L. kirschnerii (NR-20327), and L. borgpetersenii (NR-20151). The MICs were read on day 7 for all samples. The Etest was then performed on 109 isolates of pathogenic Leptospira spp. The MIC90 values for penicillin G, doxycycline, cefotaxime, ceftriaxone, and chloramphenicol were 0.64 units/ml and 0.19, 0.047, 0.5, and 2 μg/ml, respectively. The use of LVW agar, which enables rapid growth, isolation of single colonies, and simple antimicrobial susceptibility testing for Leptospira spp., provides an opportunity for new areas of fundamental and applied research. PMID:23114772

  5. Comparison of inhibitory mold agar to Sabouraud dextrose agar as a primary medium for isolation of fungi.

    PubMed

    Scognamiglio, Theresa; Zinchuk, Riva; Gumpeni, Pramod; Larone, Davise H

    2010-05-01

    Clinical specimens cultured on two selective fungal media, inhibitory mold agar (IMA) and Sabouraud dextrose agar (SDA), were compared with respect to recovery of fungi. Of the 840 fungal isolates recovered, 69.3% grew on both IMA and SDA; 24.9% grew only on IMA; and 5.8% grew only on SDA, showing that IMA is superior (P=0.003).

  6. Pig and Goat Blood as Substitutes for Sheep Blood in Blood-Supplemented Agar Media

    PubMed Central

    Anand, Chandar; Gordon, Rhonda; Shaw, Helene; Fonseca, Kevin; Olsen, Merle

    2000-01-01

    In many developing countries sheep and horse blood, the recommended blood supplements in bacteriological media, are not readily available, whereas pig and goat blood are. Therefore, this study examined the use of pig and goat blood as potential substitutes for sheep blood in blood-supplemented bacteriologic media commonly used in clinical microbiology laboratories. In general, the growth characteristics and colony morphologies of a wide range of aerobic and anaerobic bacteria and Candida albicans were similar on media containing pig, goat, and sheep blood, although differences were found. Enterococcus sp. uniformly produced alpha-hemolysis when incubated in CO2, but in anaerobic conditions the hemolysis varied. In contrast, beta-hemolytic streptococci produced identical hemolytic reactions on all three media. Synergistic hemolysis was not observed on pig blood agar in the CAMP test nor on goat blood agar in the reverse CAMP test. The preparation of chocolate agar (heated) with pig blood required heating to a higher temperature than with sheep or goat blood to yield suitable growth of Haemophilus species. In general, we conclude that pig and goat blood are suitable alternatives to sheep blood for use in bacteriological media in settings where sheep and horse blood are not readily available. PMID:10655351

  7. Pig and goat blood as substitutes for sheep blood in blood-supplemented agar media.

    PubMed

    Anand, C; Gordon, R; Shaw, H; Fonseca, K; Olsen, M

    2000-02-01

    In many developing countries sheep and horse blood, the recommended blood supplements in bacteriological media, are not readily available, whereas pig and goat blood are. Therefore, this study examined the use of pig and goat blood as potential substitutes for sheep blood in blood-supplemented bacteriologic media commonly used in clinical microbiology laboratories. In general, the growth characteristics and colony morphologies of a wide range of aerobic and anaerobic bacteria and Candida albicans were similar on media containing pig, goat, and sheep blood, although differences were found. Enterococcus sp. uniformly produced alpha-hemolysis when incubated in CO(2), but in anaerobic conditions the hemolysis varied. In contrast, beta-hemolytic streptococci produced identical hemolytic reactions on all three media. Synergistic hemolysis was not observed on pig blood agar in the CAMP test nor on goat blood agar in the reverse CAMP test. The preparation of chocolate agar (heated) with pig blood required heating to a higher temperature than with sheep or goat blood to yield suitable growth of Haemophilus species. In general, we conclude that pig and goat blood are suitable alternatives to sheep blood for use in bacteriological media in settings where sheep and horse blood are not readily available.

  8. [Development of chromogenic agar medium for isolation of enterohaemorrhagic Escherichia coli O26].

    PubMed

    Ikedo, M; Komatsu, O; Hara-Kudo, Y; Yamamoto, S; Kumagai, S

    2001-04-01

    Agar media for isolation of enterohaemorrhagic Escherichia coli (EHEC) have been developed primarily for E. coli O157, because this bacterium has most frequently caused EHEC infection. However, there have been few studies for isolation of other serotypes of EHEC, and media appropriate for isolation of such organisms, especially from food samples, are not yet available. Among such serotypes, E. coli O26 has often been isolated from clinical specimens from patients and animals, but not from food samples in outbreaks, because of lack of an appropriate method for isolation. In this study, we tried to develop a new chromogenic agar medium for selective isolation of E. coli O26 using the characteristics of E. coli O26. Fifteen strains of E. coli O26, 11 strains of E. coli O157 and 36 strains of other sero-types E. coli were tested for fermentation of rhamnose, cellobiose, dulcitol, salicin, raffinose, sorbitol, sucrose, lactose, mannitol, arabinose, maltose, xylose and glucose. Rhamnose was fermented by all E. coli strains except for E. coli O26. The other substrates were not effective for differentiating E. coli O26 from the other strains of E. coli. Thus the medium containing rhamnose and 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside, which is a substrate of beta-galactosidase specific to coliforms, produced a color of E. coli O26 colonies different from colors of the other bacteria. Furthermore, cefixime and sodium tellulite were added to the composition of the medium for gaining higher selectivity.

  9. Comparative evaluation of chromogenic agar medium and conventional culture system for isolation and presumptive identification of uropathogens

    PubMed Central

    Akter, Laila; Haque, Rezwana; Salam, Md. Abdus

    2014-01-01

    Objective: Urine is the most frequent specimen received for culture/sensitivity by clinical laboratories. The microbiological performance of HiCrome UTI agar medium was compared with Blood agar and MacConkey agar for isolation and presumptive identification of bacteria from urine culture. Methods: A total of 443 consecutively collected midstream and/or catheter-catch urine samples from patients attending the Islami Bank Medical College Hospital, Rajshahi, Bangladesh during January to December, 2012 were cultured. Urine samples showing pus cells ≥ 5/HPF were inoculated on to Blood agar (BA), MacConkey agar (MAC) and HiCrome UTI agar (CA) media simultaneously and incubated overnight aerobically at 370C. Rate of isolation and presumptive identification of bacterial species were compared for different media. Results: Culture yielded a total of 199 bacterial isolates from 189 (42.67%) positive plates including 179 (40.40%) unimicrobial and 10 (2.26%) polymicrobial (mixed growth of pair of bacteria) growths. Both HiCrome UTI agar and Blood agar media supported 100% growths while 151 (75.88%) growths were observed on MacConkey agar. The rate of presumptive identification was found significantly higher on HiCrome UTI agar (97.49%) than MAC agar (67.34%) (P<0.001) as primary urine culture medium. Of 199 isolates, E. coli was found to be the leading uropathogen isolated from 118 (59.30%) samples with its presumptive identification rate of 95.76%, 93.22% and 5.93% on CA, MAC and BA respectively. All 10 (100%) polymicrobial growths were demonstrated distinctly on CA against only 01(10%) on each BA and MAC. Conclusion: HiCrome UTI agar was found to be more useful as primary urine culture medium in both higher rate of isolation and presumptive identification of uropathogens in comparison to conventional media. Its inherent characteristics in demonstrating polymicrobial growth and ease of rapid identification by distinct colony colour are unique. PMID:25225521

  10. Comparison of CHROMagar Salmonella Medium and Hektoen Enteric Agar for Isolation of Salmonellae from Stool Samples

    PubMed Central

    Gaillot, Olivier; Di Camillo, Patrick; Berche, Patrick; Courcol, René; Savage, Colette

    1999-01-01

    CHROMagar Salmonella (CAS), a new chromogenic medium, was retrospectively compared to Hektoen enteric agar (HEA) with 501 Salmonella stock isolates and was then prospectively compared to HEA for the detection and presumptive identification of Salmonella spp. with 508 stool samples before and after enrichment. All stock cultures (100%), including cultures of H2S-negative isolates, yielded typical mauve colonies on CAS, while 497 (99%) isolates produced typical lactose-negative, black-centered colonies on HEA. Following overnight incubation at 37°C, a total of 20 Salmonella strains were isolated from the 508 clinical samples. Sensitivities for primary plating and after enrichment were 95% (19 isolates) and 100% (20 isolates), respectively, for CAS and 80% (16 isolates) and 100% (20 isolates), respectively, for HEA. The specificity of CAS (88.9%) was significantly higher than that of HEA (78.5%; P < 0.0001). On the basis of its good sensitivity and specificity, CAS medium can be recommended for use for primary plating when human stool samples are screened for Salmonella spp. PMID:9986847

  11. Enhanced chlorine resistance of tap water-adapted Legionella pneumophila as compared with agar medium-passaged strains.

    PubMed

    Kuchta, J M; States, S J; McGlaughlin, J E; Overmeyer, J H; Wadowsky, R M; McNamara, A M; Wolford, R S; Yee, R B

    1985-07-01

    Previous studies have shown that bacteria maintained in a low-nutrient "natural" environment such as swimming pool water are much more resistant to disinfection by various chemical agents than strains maintained on rich media. In the present study a comparison was made of the chlorine (Cl2) susceptibility of hot-water tank isolates of Legionella pneumophila maintained in tap water and strains passaged on either nonselective buffered charcoal-yeast extract or selective differential glycine-vancomycin-polymyxin agar medium. Our earlier work has shown that environmental and clinical isolates of L. pneumophila maintained on agar medium are much more resistant to Cl2 than coliforms are. Under the present experimental conditions (21 degrees C, pH 7.6 to 8.0, and 0.25 mg of free residual Cl2 per liter, we found the tap water-maintained L. pneumophila strains to be even more resistant than the agar-passaged isolates. Under these conditions, 99% kill of tap water-maintained strains of L. pneumophila was usually achieved within 60 to 90 min compared with 10 min for agar-passaged strains. Samples from plumbing fixtures in a hospital yielded legionellae which were "super"-chlorine resistant when assayed under natural conditions. After one agar passage their resistance dropped to levels of comparable strains which had not been previously exposed to additional chlorination. These studies more closely approximate natural conditions than our previous work and show that tap water-maintained L. pneumophila is even more resistant to Cl2 than its already resistant agar medium-passaged counterpart.

  12. Interplanetary medium data book, supplement, 1975 - 1978

    NASA Technical Reports Server (NTRS)

    King, J. H.

    1979-01-01

    Since the issurance of the Interplanetary Medium Data Book (NSSDC/WDC-A-R&S 77-04, 1977) which contains plots and listings of hourly average interplanetary field and plasma parameters covering the period November 27, 1963 through December 30, 1975, additional data are available which fill some 1975 data gaps and which extend the data coverage well into 1978. This supplement contains all the presently available data for the years 1975-1978, Interplanetary magnetic field (IMF) data are from the IMP 8 triaxial fluxgate magnetometer experiment. Derived plasma parameters are form the IMP 7 and IMP 8 instruments. Some of the early 1975 IMF data are from a HEOS 1 experiment.

  13. Supplementation of CHROMagar Candida medium with Pal's medium for rapid identification of Candida dubliniensis.

    PubMed

    Sahand, Ismail H; Moragues, María D; Eraso, Elena; Villar-Vidal, María; Quindós, Guillermo; Pontón, José

    2005-11-01

    CHROMagar Candida medium is used for the isolation and identification of Candida species, but it does not differentiate Candida albicans from Candida dubliniensis. This differentiation can be achieved by using Pal's agar, which cannot be used in primary isolation. We have combined both media to obtain a new medium that can be used for the isolation and identification of C. dubliniensis in primary cultures.

  14. Evaluation of a novel chromogenic agar medium for isolation and differentiation of vancomycin-resistant Enterococcus faecium and Enterococcus faecalis isolates.

    PubMed

    Ledeboer, Nathan A; Das, Kingshuk; Eveland, Michael; Roger-Dalbert, Céline; Mailler, Sandrine; Chatellier, Sonia; Dunne, William Michael

    2007-05-01

    The development of reliable and rapid methods for the identification of patients colonized with vancomycin-resistant enterococci (VRE) is central to the containment of this agent within a hospital environment. To this end, we evaluated a prototype chromogenic agar medium (VRE-BMX; bioMérieux, Marcy l'Etoile, France) used to recover VRE from clinical specimens. This medium can also identify isolated colonies as either vancomycin-resistant Enterococcus faecium or Enterococcus faecalis, based on distinct colony colors. We compared the performance of VRE-BMX with bile esculin azide agar supplemented with vancomycin (BEAV). For this study, 147 stool samples were plated on each test medium and examined after 24 and 48 h of incubation. At 24 h, the sensitivity and specificity of each medium were as follows: BEAV, 90.9% and 89.9%, respectively; VRE-BMX, 96.4% and 96.6%, respectively. The positive predictive values (PPV) of VRE-BMX and BEAV at 24 h were 89.8% and 80.7%, respectively. VRE-BMX provided the identification of 10 isolates of vancomycin-resistant E. faecalis and 4 isolates of vancomycin-resistant E. faecium that were not recovered by BEAV. Further, VRE-BMX was capable of identifying patients colonized with both E. faecium and E. faecalis, a feature useful for infection control purposes that is not a function of BEAV. In terms of the recovery of vancomycin-resistant E. faecium and E. faecalis, the sensitivity and PPV were as follows: BEAV, 75.7% and 74.6%, respectively; VRE-BMX, 95.5% and 91.3%, respectively. In this initial evaluation, we found that VRE-BMX provided improved recovery of VRE from stool specimens, with the added advantage of being able to differentiate between vancomycin-resistant E. faecalis and E. faecium. Extending the incubation period beyond 24 h did not significantly improve the recovery of VRE and resulted in decreased specificity.

  15. A new chromogenic agar medium, chromID VRE, to screen for vancomycin-resistant Enterococcus faecium and Enterococcus faecalis.

    PubMed

    Ledeboer, Nathan A; Tibbetts, Robert J; Dunne, William M

    2007-12-01

    We compared the performance of a chromogenic agar medium chromID VRE (bioMérieux, Marcy-l'Etoile, France) designed to recover and identify vancomycin-resistant enterococci (VRE) from clinical specimens with bile esculin azide vancomycin (BEAV) agar. For this study, 120 stool specimens were plated on chromID VRE and BEAV and examined after 24 and 48 h. At 24 h, the sensitivity and specificity were as follows: BEAV, 90.2% and 73%, respectively; chromID VRE, 86.3% and 100.0%, respectively. Furthermore, we determined that the sensitivity and specificity of chromID VRE for Enterococcus faecium were 85.4% and 100%, respectively, and for Enterococcus faecalis, 90% and 100%, respectively. We conclude that chromID VRE provides an equivalent sensitivity for the recovery of VRE from stool specimens, with improved specificity, and the added advantage of providing differentiation between vancomycin-resistant E. faecium and E. faecalis.

  16. Comparison of the BBL CHROMagar Staph aureus Agar Medium to Conventional Media for Detection of Staphylococcus aureus in Respiratory Samples

    PubMed Central

    Flayhart, Diane; Lema, Clara; Borek, Anita; Carroll, Karen C.

    2004-01-01

    Screening for Staphylococcus aureus has become routine in certain patient populations. This study is the first clinical evaluation of the BBL CHROMagar Staph aureus agar (CSA) medium (BD Diagnostics, Sparks, Md.) for detection of S. aureus in nasal surveillance cultures and in respiratory samples from cystic fibrosis (CF) patients. S. aureus colonies appear mauve on CSA. Other organisms are inhibited or produce a distinctly different colony color. S. aureus was identified from all media by slide coagulase, exogenous DNase, and mannitol fermentation assays. Susceptibility testing was performed using the agar dilution method. A total of 679 samples were evaluated. All samples were inoculated onto CSA. Nasal surveillance cultures were inoculated onto sheep blood agar (SBA) (BD Diagnostics), and samples from CF patients were inoculated onto mannitol salt agar (MSA) (BD Diagnostics). Of the 679 samples cultured, 200 organisms produced a mauve color on CSA (suspicious for S. aureus) and 180 were positive for S. aureus on SBA or MSA. Of 200 CSA-positive samples 191 were identified as S. aureus. Nine mauve colonies were slide coagulase negative and were subsequently identified as Staphylococcus lugdunensis (one), Staphylococcus epidermidis (three), Staphylococcus haemolyticus (one), and Corynebacterium species (four). CSA improved the ability to detect S. aureus by recovering 12 S. aureus isolates missed by conventional media. Of the 192 S. aureus isolates recovered, 122 were methicillin susceptible and 70 were methicillin resistant. Overall, the sensitivity and specificity of CSA in this study were 99.5 and 98%, respectively. There was no difference in the performance of the slide coagulase test or in susceptibility testing performed on S. aureus recovered from CSA compared to SBA or MSA. Our data support the use of CSA in place of standard culture media for detection of S. aureus in heavily contaminated respiratory samples. PMID:15297498

  17. Supplementation of CHROMagar Candida Medium with Pal's Medium for Rapid Identification of Candida dubliniensis

    PubMed Central

    Sahand, Ismail H.; Moragues, María D.; Eraso, Elena; Villar-Vidal, María; Quindós, Guillermo; Pontón, José

    2005-01-01

    CHROMagar Candida medium is used for the isolation and identification of Candida species, but it does not differentiate Candida albicans from Candida dubliniensis. This differentiation can be achieved by using Pal's agar, which cannot be used in primary isolation. We have combined both media to obtain a new medium that can be used for the isolation and identification of C. dubliniensis in primary cultures. PMID:16272515

  18. Epidemiology of Klebsiella oxytoca-associated diarrhea detected by Simmons citrate agar supplemented with inositol, tryptophan, and bile salts.

    PubMed

    Cheng, Vincent C C; Yam, Wing-Cheong; Tsang, Lee-Lee; Yau, Miranda C Y; Siu, Gilman K H; Wong, Sally C Y; Chan, Jasper F W; To, Kelvin K W; Tse, Herman; Hung, Ivan F N; Tai, Josepha W M; Ho, Pak-Leung; Yuen, Kwok-Yung

    2012-05-01

    We studied the clinical and epidemiological characteristics of Klebsiella oxytoca-associated diarrhea in hospitalized patients in Hong Kong. Between 1 November 2009 and 30 April 2011, all inositol-fermenting colonies found on Simmons citrate agar supplemented with inositol, tryptophan, and bile salts (SCITB agar) used for the culturing of diarrheal stool samples were screened by a spot indole test for K. oxytoca. The overall sensitivity of SCITB agar plus the spot indole test (93.3%) for the detection of K. oxytoca in stool samples was superior to that of MacConkey agar (63.3%), while the specificities were 100% and 60.4%, respectively. The former achieved a 23-fold reduction in the workload and cost of subsequent standard biochemical identifications. Cytotoxin production and the clonality of K. oxytoca were determined by a cell culture cytotoxicity neutralization assay using HEp-2 cells and pulsed-field gel electrophoresis (PFGE), respectively. Of 5,581 stool samples from 3,537 patients, K. oxytoca was cultured from 117/5,581 (2.1%) stool samples from 104/3,537 (2.9%) patients. Seventy-six of 104 (73.1%) patients with K. oxytoca had no copathogens in their diarrheal stool samples. Twenty-four (31.6%) of 76 patients carried cytotoxin-producing strains, which were significantly associated with antibiotic therapy after hospital admission (50% versus 21.2%; P = 0.01). Health care-associated diarrhea was found in 44 (42%) of 104 patients with K. oxytoca, but there was no epidemiological linkage suggestive of a nosocomial outbreak, and PFGE showed a diverse pattern. None of the patients with cytotoxin-producing K. oxytoca developed antibiotic-associated hemorrhagic colitis, suggesting that K. oxytoca can cause a mild disease manifesting as uncomplicated antibiotic-associated diarrhea with winter seasonality.

  19. Methicillin-Resistant Staphylococcus aureus Grown on Vancomycin-Supplemented Screening Agar Displays Enhanced Biofilm Formation

    PubMed Central

    Chang, Wenjiao; Ding, Ding; Zhang, Shanshan; Dai, Yuanyuan; Pan, Qing; Lu, Huaiwei; Luo, Qingli; Shen, Jilong

    2015-01-01

    Brain heart infusion agar containing 3 mg/liter vancomycin (BHI-V3) was used to screen for heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA). There was markedly greater biofilm formation by isolates that grew on BHI-V3 than by strains that did not grow on BHI-V3. Increased biofilm formation by hVISA may be mediated by FnbA- and polysaccharide intercellular adhesin-dependent pathways, and upregulation of atlA and sarA may also contribute to enhanced biofilm formation by hVISA upon prolonged exposure to vancomycin. PMID:26459889

  20. Visualization of the Charcoal Agar Resazurin Assay for Semi-quantitative, Medium-throughput Enumeration of Mycobacteria

    PubMed Central

    Gold, Ben; Lopez Quezada, Landys; Glasheen, Jou; Ballinger, Elaine; Somersan-Karakaya, Selin; Warrier, Thulasi; Nathan, Carl

    2016-01-01

    There is an urgent need to discover and progress anti-infectives that shorten the duration of tuberculosis (TB) treatment. Mycobacterium tuberculosis, the etiological agent of TB, is refractory to rapid and lasting chemotherapy due to the presence of bacilli exhibiting phenotypic drug resistance. The charcoal agar resazurin assay (CARA) was developed as a tool to characterize active molecules discovered by high-throughput screening campaigns against replicating and non-replicating M. tuberculosis. Inclusion of activated charcoal in bacteriologic agar medium helps mitigate the impact of compound carry-over, and eliminates the requirement to pre-dilute cells prior to spotting on CARA microplates. After a 7-10 day incubation period at 37 °C, the reduction of resazurin by mycobacterial microcolonies growing on the surface of CARA microplate wells permits semi-quantitative assessment of bacterial numbers via fluorometry. The CARA detects approximately a 2-3 log10 difference in bacterial numbers and predicts a minimal bactericidal concentration leading to ≥99% bacterial kill (MBC≥99). The CARA helps determine whether a molecule is active on bacilli that are replicating, non-replicating, or both. Pilot experiments using the CARA facilitate the identification of which concentration of test agent and time of compound exposure require further evaluation by colony forming unit (CFU) assays. In addition, the CARA can predict if replicating actives are bactericidal or bacteriostatic. PMID:28060290

  1. Evaluation of potassium-clavulanate-supplemented modified charcoal-cefoperazone-deoxycholate agar for enumeration of Campylobacter in chicken carcass rinse.

    PubMed

    Chon, Jung-Whan; Kim, Hong-Seok; Kim, Hyunsook; Oh, Deog-Hwan; Seo, Kun-Ho

    2014-05-01

    Potassium-clavulanate-supplemented modified charcoal-cefoperazone-deoxycholate agar (C-mCCDA) that was described in our previous study was compared with original mCCDA for the enumeration of Campylobacter in pure culture and chicken carcass rinse. The quantitative detection of viable Campylobacter cells from a pure culture, plated on C-mCCDA, is statistically similar (P > 0.05) to mCCDA. In total, 120 chickens were rinsed using 400 mL buffered peptone water. The rinses were inoculated onto C-mCCDA and mCCDA followed by incubation at 42 °C for 48 h. There was no statistical difference between C-mCCDA (45 of 120 plates; mean count, 145.5 CFU/mL) and normal mCCDA (46 of 120 plates; mean count, 160.8 CFU/mL) in the isolation rate and recovery of Campylobacter (P > 0.05) from chicken carcass rinse. The Pearson correlation coefficient value for the number of Campylobacter cells recovered in the 2 media was 0.942. However, the selectivity was much better on C-mCCDA than on mCCDA plates (P < 0.05). Significantly fewer C-mCCDA plates (33 out of 120 plates; mean count, 1.9 CFU/mL) were contaminated with non-Campylobacter cells than the normal mCCDA plates (67 out of 120 plates; mean count, 27.1 CFU/mL). The C-mCCDA may provide improved results for enumeration of Campylobacter in chicken meat alternative to mCCDA with its increased selectivity the modified agar possess.

  2. Evaluation of Mueller-Hinton-agar as a simple medium for the germ tube production of Candida albicans and Candida dubliniensis.

    PubMed

    Rimek, Dagmar; Fehse, Brigitte; Göpel, Petra

    2008-05-01

    Candida albicans is the most frequently isolated yeast species from clinical specimens. A classical rapid presumptive differentiation from non-albicans species is based on its ability to produce germ tubes after incubation in human serum. The only non-albicans Candida species producing germ tubes is Candida dubliniensis. In this study, we evaluated Mueller-Hinton-agar (MH-agar) as a medium for germ tube formation of C. albicans and C. dubliniensis. A total of 859 yeast isolates from stool samples, including 632 strains of C. albicans, 10 C. dubliniensis and 217 other yeast strains from 20 different species, were grown on Sabouraud glucose (2%) agar at 37 degrees C for 24-72 h. Species were identified by standard methods. For the germ tube test (GTT), an inoculum from a single colony was streaked onto a MH-agar plate and covered by a sterile coverslip. After incubation at 37 degrees C for 2 h, the MH plates were examined using a light microscope at x200. The GTT was positive in 578 of 632 C. albicans strains (sensitivity 91.5%), in six of 10 C. dubliniensis strains (sensitivity 60.0%), and in none of the other yeast strains. MH-agar is a suitable medium for the GTT and the presumptive identification of C. albicans. It is safer to use than human serum and is widely available in microbiology laboratories.

  3. Performance of CHROMagar Selective Medium and Oxacillin Resistance Screening Agar Base for Identifying Staphylococcus aureus and Detecting Methicillin Resistance

    PubMed Central

    Kluytmans, Jan; Van Griethuysen, Arjanne; Willemse, Piet; Van Keulen, Peter

    2002-01-01

    Two new selective media, oxacillin resistance screening agar base (ORSAB) and CHROMagar Staph aureus (CSA), were evaluated for identification of Staphylococcus aureus and for screening of methicillin resistance by addition of antimicrobial agents to these media. A well-defined collection consisting of 1,140 staphylococci was used. A total of 624 were S. aureus, of which 358 were methicillin susceptible and 266 were methicillin resistant, and 516 were coagulase-negative staphylococci. The methicillin-resistant S. aureus (MRSA) strains were selected based on the results of phage typing; 247 different types were included in the analysis. For identification of S. aureus, both media performed better after 24 h than after 48 h. The sensitivities at 24 h were comparable (CSA, 98.6%; ORSAB, 97.1%), but the specificity of CSA was significantly higher (CSA, 97.1%; ORSAB, 92.1%). For screening of methicillin resistance, antibiotic supplements were added to both media. The sensitivity was lower after 24 h (CSA, 58.6%; ORSAB, 84.2%) and increased significantly after 48 h (CSA, 77.5%; ORSAB, 91.4%). At both time intervals ORSAB was significantly more sensitive than CSA. However, the specificities of both media were high after 24 h (CSA, 99.1%; ORSAB, 98.3%) and decreased significantly after 48 h of incubation (CSA, 94.7%; ORSAB, 95.5%). In conclusion, for identification of S. aureus, CSA is more accurate than ORSAB because of a significantly higher specificity. For screening of MRSA, ORSAB performs better than CSA, but the usefulness in clinical practice is limited because a significant number of strains are not detected. PMID:12089266

  4. Development of a selective agar plate for the detection of Campylobacter spp. in fresh produce.

    PubMed

    Yoo, Jin-Hee; Choi, Na-Young; Bae, Young-Min; Lee, Jung-Su; Lee, Sun-Young

    2014-10-17

    This study was conducted to develop a selective medium for the detection of Campylobacter spp. in fresh produce. Campylobacter spp. (n=4), non-Campylobacter (showing positive results on Campylobacter selective agar) strains (n=49) isolated from fresh produce, indicator bacteria (n=13), and spoilage bacteria isolated from fresh produce (n=15) were plated on four Campylobacter selective media. Bolton agar and modified charcoal cefoperazone deoxycholate agar (mCCDA) exhibited higher sensitivity for Campylobacter spp. than did Preston agar and Hunt agar, although certain non-Campylobacter strains isolated from fresh produce by using a selective agar isolation method, were still able to grow on Bolton agar and mCCDA. To inhibit the growth of non-Campylobacter strains, Bolton agar and mCCDA were supplemented with 5 antibiotics (rifampicin, polymyxin B, sodium metabisulfite, sodium pyruvate, ferrous sulfate) and the growth of Campylobacter spp. (n=7) and non-Campylobacter strains (n=44) was evaluated. Although Bolton agar supplemented with rifampicin (BR agar) exhibited a higher selectivity for Campylobacter spp. than did mCCDA supplemented with antibiotics, certain non-Campylobacter strains were still able to grow on BR agar (18.8%). When BR agar with various concentrations of sulfamethoxazole-trimethoprim were tested with Campylobacter spp. (n=8) and non-Campylobacter (n=7), sulfamethoxazole-trimethoprim was inhibitory against 3 of 7 non-Campylobacter strains. Finally, we validated the use of BR agar containing 50mg/L sulfamethoxazole (BRS agar) or 0.5mg/L ciprofloxacin (BRCS agar) and other selective agars for the detection of Campylobacter spp. in chicken and fresh produce. All chicken samples were positive for Campylobacter spp. when tested on mCCDA, BR agar, and BRS agar. In fresh produce samples, BRS agar exhibited the highest selectivity for Campylobacter spp., demonstrating its suitability for the detection of Campylobacter spp. in fresh produce.

  5. Interplanetary medium data book: Supplement 3A, 1977-1985

    NASA Technical Reports Server (NTRS)

    Couzens, David A.; King, Joseph H.

    1986-01-01

    Supplement 3 of the Interplanetary Medium Data Book contains a detailed discussion of a data set compilation of hourly averaged interplanetary plasma and magnetic field parameters. The discussion addresses data sources, systematic and random differences, time shifting of ISEE 3 data, and plasma normalizations. Supplement 3 also contains solar rotation plots of field and plasma parameters. Supplement 3A contains computer-generated listings of selected parameters from the composite data set. These parameters are bulk speed (km/sec), density (per cu cm), temperature (in units of 1000 K) and the IMF parameters: average magnitude, latitude and longitude angles of the vector made up of the average GSE components, GSM Cartesian components, and the vector standard deviation. The units of field magnitude, components, and standard deviation are gammas, while the units of field direction angles and degrees.

  6. Comparison of CHROMagar Salmonella Medium and Xylose-Lysine-Desoxycholate and Salmonella-Shigella Agars for Isolation of Salmonella Strains from Stool Samples

    PubMed Central

    Maddocks, Susan; Olma, Tom; Chen, Sharon

    2002-01-01

    The growth and appearance of 115 stock Salmonella isolates on a new formulation of CHROMagar Salmonella (CAS) medium were compared to those on xylose-lysine-desoxycholate agar (XLD), Salmonella-Shigella agar (SS), and Hektoen enteric agar (HEA) media. CAS medium was then compared prospectively to XLD and SS for the detection and presumptive identification of Salmonella strains in 500 consecutive clinical stool samples. All stock Salmonella isolates produced typical mauve colonies on CAS medium. Nine Salmonella strains were isolated from clinical specimens. The sensitivities for the detection of salmonellae after primary plating on CAS medium and the combination of XLD and SS after enrichment were 100%. The specificity for the detection of salmonellae after primary plating on CAS medium (83%) was significantly (P < 0.0001) higher than that after primary plating on the combination of SS and XLD media (55%) (a 28% difference in rates; 95% confidence interval, 23.0 to 34%). Twenty-nine non-Salmonella organisms produced mauve colonies on CAS medium, including 17 Candida spp. (59%) and 8 Pseudomonas spp. (28%). These were easily excluded as salmonellae by colony morphology, microscopic examination of a wet preparation, or oxidase testing. One biochemically inert Escherichia coli isolate required further identification to differentiate it from Salmonella spp. The use of plating on CAS medium demonstrated high levels of sensitivity and specificity and reduced the time to final identification of Salmonella spp., resulting in substantial cost savings. It can be recommended for use for the primary isolation of Salmonella spp. from stool specimens. Other media (e.g., XLD) are required to detect Shigella spp. concurrently. PMID:12149365

  7. [Detection of TDH-producing Vibrio parahaemolyticus O3:K6 from naturally contaminated shellfish using an immunomagnetic separation method and chromogenic agar medium].

    PubMed

    Hara-Kudo, Y; Sugiyama, K; Nishina, T; Saitoh, A; Nakagawa, H; Ichihara, T; Konuma, H; Hasegawa, J; Kumagai, S

    2001-11-01

    We attempted to isolate TDH-producing Vibrio parahaemolyticus O3:K6 from shellfish. Asari samples were incubated with TSB supplemented with 2% (w/v) NaCl for 6 h, and then the 6-h cultures were incubated with salt polymyxin broth for 18 h. After the two-step enrichment, a 1 ml portion of the culture was treated with magnetic beads coated with K6 antibody for immunoconcentration of V. parahaemolyticus O3:K6. The immunoconcentrated and untreated cultures were plated onto a chromogenic agar and TCBS agar media for isolation of V. parahaemolyticus. TDH-producing V. parahaemolyticus O3:K6 was isolated from 3 out of 66 lots (4.5%) of naturally contaminated Asari. Six of 4,265 colonies suspected as V. parahaemolyticus (0.14%) were TDH-producing V. parahaemolyticus O3:K6.

  8. Cultivation of Spirulina maxima in medium supplemented with sugarcane vinasse.

    PubMed

    dos Santos, Raquel Rezende; Araújo, Ofélia de Queiroz Fernandes; de Medeiros, José Luiz; Chaloub, Ricardo Moreira

    2016-03-01

    The feasibility of sugarcane vinasse as supplement in growth medium of Spirulina maxima was investigated. The cell was cultivated under autotrophic (no vinasse, 70 μmol photons m(-2) s(-1)), heterotrophic (no light, culture medium supplemented with vinasse at 0.1% v/v and 1.0% v/v) and mixotrophic conditions (70 μmol photons m(-2) s(-1), vinasse at 0.1% v/v and 1.0% v/v). These preliminary results suggested a cyclic two-stage cultivation - CTSC, with autotrophic condition during light phase of the photoperiod (12 h, 70-200 μmol photons m(-2) s(-1)) and heterotrophic condition during dark phase (12h, 3.0% v/v vinasse). The adopted CTSC strategy consisted in three cycles with 75% withdrawal of suspension and reposition of medium containing 3.0% v/v vinasse, separated by autotrophic rest periods of few days between cycles. Results show an increase of biomass concentration between 0.495 g L(-1) and 0.609 g L(-1) at the 7th day of each cycle and high protein content (between 74.3% and 77.3% w/w).

  9. Interplanetary medium data book, supplement 4, 1985-1988

    NASA Technical Reports Server (NTRS)

    King, Joseph H.

    1989-01-01

    An extension is presented of the series of Interplanetary Medium Data Books and supplements which have been issued by the National Space Science Data Center since 1977. This volume contains solar wind magnetic field (IMF) and plasma data from the IMP 8 spacecraft for 1985 to 1988, and 1985 IMF data from the Czechoslovakian Soviet Prognoz 10 spacecraft. The normalization of the MIT plasma density and temperature, which has been discussed at length in previous volumes, is implemented as before, using the same normalization constants for 1985 to 1988 data as for the earlier data.

  10. Interplanetary medium data book, supplement 5, 1988-1993

    NASA Technical Reports Server (NTRS)

    King, Joseph H.; Papitashvili, Natalia E.

    1994-01-01

    This publication represents an extension of the series of Interplanetary Medium Data Books and supplements that have been issued by the National Space Science Data Center since 1977. This volume contains solar wind magnetic field and plasma data from the IMP 8 spacecraft for 1988 through the end of 1993. The normalization of the MIT plasma density and temperature, which has been discussed at length in previous volumes, is implemented as before, using the same normalization constants for 1988-1993 data as for the earlier data. Owing to a combination of non-continuity of IMP 8 telemetry acquisition and IMP's being out of the solar wind for about 40 percent of its orbit, the annual solar wind coverage for 1988-1993 is 40 plus or minus 5 percent. The plots and listings of this supplement are in essentially the same format as in previous supplements. Days for which neither IMF nor plasma data were available for any hours are omitted from the listings.

  11. Use of the selective agar medium CREAD for monitoring the level of airborne spoilage moulds in cheese production.

    PubMed

    Kure, Cathrine Finne; Borch, Elisabeth; Karlsson, Ingela; Homleid, Jens Petter; Langsrud, Solveig

    2008-02-29

    It was investigated if a selective medium for common cheese spoiling moulds (CREAD) could give more relevant information than a general mould medium in hygienic air-sampling in cheese factories. A total of 126 air-samples were taken in six Nordic cheese factories using the general mould medium DG18 and CREAD. The level and genera of air-borne mould was determined. Identification to species-level was performed for a selection of samples. In five cheese factories the mycobiota was dominated by Penicillium spp. and in one cheese factory by Cladosporium spp. The concentration of air-borne moulds varied between the cheese factories ranging from 1 to 270 cfu/m3 on DG18 with a median value of 17. The number of mould colonies was in general lower at CREAD. Identification indicated that CREAD supported growth of common spoilage moulds for cheese, such as Penicillium palitans and P. commune. The mycobiota on DG18 also consisted of moulds not commonly associated with spoilage of cheese, such as Cladosporium spp., P. brevicompactum and P. chrysogenum. Contamination of cheese with mould is periodically a problem in production of semi-hard cheese and the level of air-borne mould is therefore routinely monitored in cheese factories. A clear correlation between the total number of moulds in air and mould growth on products is not always found. The conclusion from the investigation is that it is recommended to use a selective medium for cheese spoilage moulds, such as CREAD in hygienic monitoring.

  12. Characterization of the selective inhibition of growth of virulent Legionella pneumophila by supplemented Mueller-Hinton medium.

    PubMed Central

    Catrenich, C. E.; Johnson, W.

    1989-01-01

    The phenotypic difference between virulent and avirulent Legionella pneumophila with regard to growth on supplemented Mueller-Hinton (SMH) agar was investigated. Defined populations of virulent and avirulent L. pneumophila were inoculated onto hybrid growth media containing the combination of SMH agar components with potassium phosphate-buffered charcoal-yeast extract agar. The casein acid hydrolysate component of SMH agar was found to be inhibitory to the growth of virulent but not avirulent cells. The selectively inhibitory component of the casein acid hydrolysate was identified as NaCl. Images PMID:2722245

  13. Human amniotic fluid cells grown in a hormone-supplemented medium: suitability for prenatal diagnosis.

    PubMed Central

    Chang, H C; Jones, O W; Masui, H

    1982-01-01

    A new supplemented medium has been developed to improve human amniotic fluid cell growth and to reduce the dependence on exogenously added serum. The medium consists of a mixture of Ham's F12 medium and Dulbecco's modified Eagle's medium supplemented with Hepes, antibiotics, and 10 growth-promoting factors at 4% fetal bovine serum. Good clonal growth is achieved consistently in 8--13 days and is associated with large numbers of metaphase cells. Primary clones may be analyzed directly, thereby reducing difficulty with interpretation of chromosomal mosaicism. This medium could also be used for cultivation of fetal solid tissues and peripheral blood cultures of lymphocytes. Images PMID:6956891

  14. The fungicidal and phytotoxic properties of benomyl and PPM in supplemented agar media supporting transgenic arabidopsis plants for a Space Shuttle flight experiment

    NASA Technical Reports Server (NTRS)

    Paul, A. L.; Semer, C.; Kucharek, T.; Ferl, R. J.

    2001-01-01

    Fungal contamination is a significant problem in the use of sucrose-enriched agar-based media for plant culture, especially in closed habitats such as the Space Shuttle. While a variety of fungicides are commercially available, not all are equal in their effectiveness in inhibiting fungal contamination. In addition, fungicide effectiveness must be weighed against its phytotoxicity and in this case, its influence on transgene expression. In a series of experiments designed to optimize media composition for a recent shuttle mission, the fungicide benomyl and the biocide "Plant Preservative Mixture" (PPM) were evaluated for effectiveness in controlling three common fungal contaminants, as well as their impact on the growth and development of arabidopsis seedlings. Benomyl proved to be an effective inhibitor of all three contaminants in concentrations as low as 2 ppm (parts per million) within the agar medium, and no evidence of phytotoxicity was observed until concentrations exceeded 20 ppm. The biocide mix PPM was effective as a fungicide only at concentrations that had deleterious effects on arabidopsis seedlings. As a result of these findings, a concentration of 3 ppm benomyl was used in the media for experiment PGIM-01 which flew on shuttle Columbia mission STS-93 in July 1999.

  15. The fungicidal and phytotoxic properties of benomyl and PPM in supplemented agar media supporting transgenic arabidopsis plants for a Space Shuttle flight experiment.

    PubMed

    Paul, A L; Semer, C; Kucharek, T; Ferl, R J

    2001-05-01

    Fungal contamination is a significant problem in the use of sucrose-enriched agar-based media for plant culture, especially in closed habitats such as the Space Shuttle. While a variety of fungicides are commercially available, not all are equal in their effectiveness in inhibiting fungal contamination. In addition, fungicide effectiveness must be weighed against its phytotoxicity and in this case, its influence on transgene expression. In a series of experiments designed to optimize media composition for a recent shuttle mission, the fungicide benomyl and the biocide "Plant Preservative Mixture" (PPM) were evaluated for effectiveness in controlling three common fungal contaminants, as well as their impact on the growth and development of arabidopsis seedlings. Benomyl proved to be an effective inhibitor of all three contaminants in concentrations as low as 2 ppm (parts per million) within the agar medium, and no evidence of phytotoxicity was observed until concentrations exceeded 20 ppm. The biocide mix PPM was effective as a fungicide only at concentrations that had deleterious effects on arabidopsis seedlings. As a result of these findings, a concentration of 3 ppm benomyl was used in the media for experiment PGIM-01 which flew on shuttle Columbia mission STS-93 in July 1999.

  16. Survival of Tribolium confusum (Coleoptera: Tenebrionidae) in basal-casein medium supplemented with sodium selenite

    SciTech Connect

    Hogan, G.R.; Cole, B.S. )

    1988-01-01

    The trace substance selenium is known to influence several systems exhibiting a high rate of cellular proliferation. Data are reported on survival patterns and times in various developmental stages of Tribolium confusum Duval reared in a defined medium supplemented with sodium selenite. Insects reared from eggs hatching in a selenium medium (Se medium) show a prolonged time in the larval period and marked larval mortality compared with those reared on unsupplemented medium. Adults emerging in an Se medium show reduced survival compared with adults transferred to such medium 1 wk after emergence. Larval survival patterns mimic those of the adult, whereby younger larvae that are transferred to Se medium appear to be more sensitive than those exposed to Se medium later in the larval stage. Transfer of Se medium-reared adults to unsupplemented medium as pupae has a beneficial effect on survival compared with adults that emerged in Se medium 1 wk before transfer.

  17. Morphological development of Morchella conica mycelium on different agar media.

    PubMed

    Guler, P; Ozkaya, E G

    2009-07-01

    The present study presents the development of mycelium of Morchella conica where different concentration of sucrose added at different agar media. For this sucrose have been added as 0.25, 0.50, 0.75, 1.00 and 1.25% concentration to wheat agar potato dextrose agar malt extract agar and complete medium yeast agar The radial growth speed, morphologic specifications, radial growth radius and pigmentation of mycelium were taken as criteria, the development period of mycelium in wheat agar was completed in 4 days and mycelium were very thin. The colonization period of the mycelium was determined; 7 days in potato dextrose agar 5 days in malt extract agar and 5 days at complete medium yeast agar. The development of the mycelium; at potato dextrose agar was dense and circular; at malt extract agar and at completed medium yeast agar was rhizomorphic. Mycelium has developed very well at sucrose medium and formed creamy and light yellow pigmentation.

  18. In vitro culture medium (IVC) supplementation with sericin improves developmental competence of ovine zygotes.

    PubMed

    Aghaz, Faranak; Hajarian, Hadi; KaramiShabankareh, Hamed

    2016-03-01

    This study was carried out to investigate the effects of supplementation of potassium simplex optimized medium (KSOM-aa) with various sericin concentrations (0, 0.1, 0.5, 1 and 2.5%) on ovine zygotes. The results indicate that the supplementation of oocyte in vitro culture medium with optimal concentration of sericin (0.1 and 0.5%) may have beneficial effects on developmental competence of in vitro-derived ovine embryos.

  19. Chlorella vulgaris production enhancement with supplementation of synthetic medium in dairy manure wastewater.

    PubMed

    Shi, Jun; Pandey, Pramod K; Franz, Annaliese K; Deng, Huiping; Jeannotte, Richard

    2016-03-01

    To identify innovative ways for better utilizing flushed dairy manure wastewater, we have assessed the effect of dairy manure and supplementation with synthetic medium on the growth of Chlorella vulgaris. A series of experiments were carried out to study the impacts of pretreatment of dairy wastewater and the benefits of supplementing dairy manure wastewater with synthetic medium on C. vulgaris growth increment and the ultrastructure (chloroplast, starch, lipid, and cell wall) of C. vulgaris cells. Results showed that the biomass production of C. vulgaris in dairy wastewater can be enhanced by pretreatment and using supplementation with synthetic media. A recipe combining pretreated dairy wastewater (40 %) and synthetic medium (60 %) exhibited an improved growth of C. vulgaris. The effects of dairy wastewater on the ultrastructure of C. vulgaris cells were distinct compared to that of cells grown in synthetic medium. The C. vulgaris growth in both synthetic medium and manure wastewater without supplementing synthetic medium was lower than the growth in dairy manure supplemented with synthetic medium. We anticipate that the results of this study will help in deriving an enhanced method of coupling nutrient-rich dairy manure wastewater for biofuel production.

  20. Genes required for and effects of alginate overproduction induced by growth of Pseudomonas aeruginosa on Pseudomonas isolation agar supplemented with ammonium metavanadate.

    PubMed

    Damron, F Heath; Barbier, Mariette; McKenney, Elizabeth S; Schurr, Michael J; Goldberg, Joanna B

    2013-09-01

    Pseudomonas aeruginosa is an opportunistic pathogen that can adapt to changing environments and can secrete an exopolysaccharide known as alginate as a protection response, resulting in a colony morphology and phenotype referred to as mucoid. However, how P. aeruginosa senses its environment and activates alginate overproduction is not fully understood. Previously, we showed that Pseudomonas isolation agar supplemented with ammonium metavanadate (PIAAMV) induces P. aeruginosa to overproduce alginate. Vanadate is a phosphate mimic and causes protein misfolding by disruption of disulfide bonds. Here we used PIAAMV to characterize the pathways involved in inducible alginate production and tested the global effects of P. aeruginosa growth on PIAAMV by a mutant library screen, by transcriptomics, and in a murine acute virulence model. The PA14 nonredundant mutant library was screened on PIAAMV to identify new genes that are required for the inducible alginate stress response. A functionally diverse set of genes encoding products involved in cell envelope biogenesis, peptidoglycan remodeling, uptake of phosphate and iron, phenazine biosynthesis, and other processes were identified as positive regulators of the mucoid phenotype on PIAAMV. Transcriptome analysis of P. aeruginosa cultures growing in the presence of vanadate showed differential expression of genes involved in virulence, envelope biogenesis, and cell stress pathways. In this study, it was observed that growth on PIAAMV attenuates P. aeruginosa in a mouse pneumonia model. Induction of alginate overproduction occurs as a stress response to protect P. aeruginosa, but it may be possible to modulate and inhibit these pathways based on the new genes identified in this study.

  1. Distribution of Streptococcus mutans and Streptococcus sobrinus in Dental Plaque of Indian Pre-School Children Using PCR and SB-20M Agar Medium

    PubMed Central

    Sharma, Arun; Sachdev, Vinod; Chopra, Radhika

    2016-01-01

    Introduction Dental caries is one of the most common infectious diseases affecting the oral cavity. Among the oral bacteria, mutans streptococci have been implicated as major cariogenic bacteria as they can produce high levels of dental caries causing substances such as lactic acid and extracellular polysaccharides. Aim The aim of the study was to detect the presence of Streptococcus mutans and Streptococcus sobrinus in dental plaque by using Polymerase Chain Reaction (PCR) method, quantification of these micro-organisms using Modified Sucrose-Bacitracin (SB-20M) agar medium and to correlate their presence in Caries Active (CA) and Caries Free (CF) pre-school children. Materials and Methods Sixty-eight pre-school children, in the age group of 3-5 years were divided equally into 34 CA and 34 CF children. Dental plaque samples were obtained for detection of these microorganisms by PCR method and quantification was done using SB-20M culture medium. The data was analyzed using statistical software SPSS version 16. For statistical analysis, the frequencies and means of Colony Forming Units (CFU) were used with CI = 95%. For bivariate analysis, Fisher exact test was used at 5% level of significance. The comparison of mean of number of CFU of S. mutans and S. sobrinus was made by Mann Whitney U test and Spearman’s Rho test at 1% level of significance was used for correlation between dmft and CFU in CA group. Results The results showed that S. sobrinus was significantly higher in CA group as compared to CF group whereas S. mutans showed no significant difference. On quantification of these micro-organisms, S. sobrinus was present in significantly higher numbers in CA group as compared to CF group. On correlating the CFU/ml of the micro-organisms with the dmft index, both the micro-organisms showed a positive correlation. Conclusion We conclude that S. mutans and S. sobrinus were detected in higher numbers in CA children as compared to CF children. PCR is a sensitive

  2. Some Experiments With Agar-Grown Seedlings

    ERIC Educational Resources Information Center

    Freeland, P. W.

    1973-01-01

    Two percent agar gel is reported as a better medium for germination and growth studies. Students can be encouraged to undertake many simple experiments and make precise observations by using this medium. (PS)

  3. Modified Hodge test using Mueller-Hinton agar supplemented with cloxacillin improves screening for carbapenemase-producing clinical isolates of Enterobacteriaceae.

    PubMed

    Takayama, Yoko; Adachi, Yuzuru; Nihonyanagi, Shin; Okamoto, Ryoichi

    2015-07-01

    Increasing numbers of clinical isolates of Enterobacteriaceae that produce carbapenemase are now being detected, with the most common carbapenemase found among Enterobacteriaceae in Japan being IMP-1-type metallo-β-lactamase. Clinical isolates of Enterobacteriaceae harbouring carbapenemases may be resistant to carbapenem antimicrobial agents, despite apparent in vitro susceptibility when tested according to Clinical and Laboratory Standards Institute criteria. We evaluated the prevalence of carbapenemase producers among isolates of Enterobacteriaceae at our hospital and assessed the performance of the modified Hodge test (MHT) for correctly identifying the phenotype. We studied 47 clinical isolates obtained between 2006 and 2010 for which the MIC of imipenem was 2 or 4 μg imipenem ml- 1. Antibacterial susceptibility testing was done for cephalosporins and carbapenems, the MHT was performed with meropenem and detection of the genes encoding IMP-1, VIM-2, KPC-2 and NDM-1-type metallo-β-lactamases was performed by PCR. Twelve isolates showed a positive result in the MHT with meropenem and were classified as carbapenemase producers. Of these 12 isolates, seven carried the gene for IMP-1 type, but not for VIM-2, KPC-2 or NDM-1 types. None of the carbapenemase genes tested were detected in the other five isolates. All five isolates were Enterobacter cloacae showing high resistance to ceftazidime and aztreonam. False-positive results were inhibited when Mueller-Hinton agar supplemented with 200 mg cloxacillin ml- 1 was used for the MHT. Five of 12 MHT-positive isolates were shown to have no carbapenemase genes and these isolates were high AmpC producers. Adding cloxacillin when performing the MHT prevented such false-positive results. The MHT with cloxacillin can overcome most problems related to detection of carbapenemases.

  4. Does supplementation of in-vitro culture medium with melatonin improve IVF outcome in PCOS?

    PubMed

    Kim, Mi Kyoung; Park, Eun A; Kim, Hyung Joon; Choi, Won Yun; Cho, Jung Hyun; Lee, Woo Sik; Cha, Kwang Yul; Kim, You Shin; Lee, Dong Ryul; Yoon, Tae Ki

    2013-01-01

    Human pre-ovulatory follicular fluid (FF) contains a higher concentration of melatonin than serum. The aim of this study was to evaluate the effect of melatonin supplementation of culture medium on the clinical outcomes of an in-vitro maturation (IVM) IVF-embryo transfer programme for patients with polycystic ovarian syndrome (PCOS). Melatonin concentrations in the culture media of granulosa cells (GC) or cumulus-oocyte-complexes (COC) were measured and the clinical outcomes after using IVM media with or without melatonin were analysed. In the culture media of GC or COC, melatonin concentrations gradually increased. When human chorionic gonadotrophin priming protocols were used, implantation rates in the melatonin-supplemented group were higher than those of the non-supplemented control group (P<0.05). Pregnancy rates were also higher, although not significantly. The findings suggest that the addition of melatonin to IVM media may improve the cytoplasmic maturation of human immature oocytes and subsequent clinical outcomes. It is speculated that follicular melatonin may be released from luteinizing GC during late folliculogenesis and that melatonin supplementation may be used to improve the clinical outcomes of IVM IVF-embryo transfer. Melatonin is primarily produced by the pineal gland and regulates a variety of important central and peripheral actions related to circadian rhythms and reproduction. Interestingly, human pre-ovulatory follicular fluid contains a higher concentration of melatonin than serum. However, in contrast to animal studies, the direct role of melatonin on oocyte maturation in the human system has not yet been investigated. So, the aim of the study was to evaluate the effect of melatonin supplementation of culture medium on the clinical outcome of an in-vitro maturation (IVM) IVF-embryo transfer programme for PCOS patients. The melatonin concentrations in culture medium of granulosa cells (GC) or cumulus-oocyte-complexes (COC) were measured and

  5. Evaluation of fluorogenic TSC agar for recovering Clostridium perfringens in groundwater samples.

    PubMed

    Araujo, M; Sueiro, R A; Gómez, M J; Garrido, M J

    2001-01-01

    Clostridium perfringens is widely recognised as a reliable water pollution indicator. Since several media can be employed for the membrane filtration enumeration of this microorganism, the main aim of this work was to investigate the ability of fluorocult-supplemented TSC-agar (Merck) for recovering Cl. perfringens from public springs used for direct human consumption. Cl. perfringens recovery was also performed on mCP agar (Cultimed) according to Directive 98/83 as well as on TSC-Agar (Merck), TSN-Agar (Merck) and SPS-Agar (BBL) media. Variance analysis of data obtained showed no statistically significant differences in the counts obtained among all media employed in this work. However, the Cl. perfringens recovery efficiencies with TSC and fluorogenic TSC agars were significantly greater (P = < 0.05) than the corresponding values of mCP and TSN media. On the other hand, the identification of typical and atypical colonies isolated from all media demonstrated that fluorogenic TSC agar was the most specific medium for Cl. perfringens recovery in groundwater samples (85.3% of typical colonies and 82.8% of atypical colonies confirmed). In summary, the membrane filtration technique with fluorogenic TSC agar showed the best performance characteristics of all the media tested as judged by their recovery efficiency and specificity in these water samples.

  6. Dietary Medium Chain Fatty Acid Supplementation Leads to Reduced VLDL Lipolysis and Uptake Rates in Comparison to Linoleic Acid Supplementation

    PubMed Central

    van Schalkwijk, Daniël B.; Pasman, Wilrike J.; Hendriks, Henk F. J.; Verheij, Elwin R.; Rubingh, Carina M.; van Bochove, Kees; Vaes, Wouter H. J.; Adiels, Martin; Freidig, Andreas P.; de Graaf, Albert A.

    2014-01-01

    Dietary medium chain fatty acids (MCFA) and linoleic acid follow different metabolic routes, and linoleic acid activates PPAR receptors. Both these mechanisms may modify lipoprotein and fatty acid metabolism after dietary intervention. Our objective was to investigate how dietary MCFA and linoleic acid supplementation and body fat distribution affect the fasting lipoprotein subclass profile, lipoprotein kinetics, and postprandial fatty acid kinetics. In a randomized double blind cross-over trial, 12 male subjects (age 51±7 years; BMI 28.5±0.8 kg/m2), were divided into 2 groups according to waist-hip ratio. They were supplemented with 60 grams/day MCFA (mainly C8:0, C10:0) or linoleic acid for three weeks, with a wash-out period of six weeks in between. Lipoprotein subclasses were measured using HPLC. Lipoprotein and fatty acid metabolism were studied using a combination of several stable isotope tracers. Lipoprotein and tracer data were analyzed using computational modeling. Lipoprotein subclass concentrations in the VLDL and LDL range were significantly higher after MCFA than after linoleic acid intervention. In addition, LDL subclass concentrations were higher in lower body obese individuals. Differences in VLDL metabolism were found to occur in lipoprotein lipolysis and uptake, not production; MCFAs were elongated intensively, in contrast to linoleic acid. Dietary MCFA supplementation led to a less favorable lipoprotein profile than linoleic acid supplementation. These differences were not due to elevated VLDL production, but rather to lower lipolysis and uptake rates. PMID:25049048

  7. A Novel Selective Medium for Isolation of Bacteroides fragilis from Clinical Specimens.

    PubMed

    Ho, Pak-Leung; Ho, Lok-Yan; Yau, Chong-Yee; Tong, Man-Ki; Chow, Kin-Hung

    2017-02-01

    A novel Bacteroides fragilis selective (BFS) medium, consisting of a brain heart infusion agar base supplemented with yeast extract, cysteine hydrochloride, bile salts, vitamin K, hemin, glucose, esculin, ferric ammonium citrate, bromothymol blue, gentamicin, kanamycin, and novobiocin, was evaluated. When BFS agar was tested with a collection of 303 bacteria of different genera, it allowed the growth of B. fragilis as large yellow colonies, with blackening of the medium after 48 h of anaerobic incubation, while the growth of most other anaerobes, facultative anaerobes, and aerobes was inhibited. In a prospective comparison of BFS agar with a routinely used medium (neomycin blood agar) in 1,209 clinical specimens, 60 B. fragilis bacteria were detected on BFS agar while 46 were detected on the routine agar (McNemar's test, P = 0.008). In conclusion, this novel medium may be added to improve the recovery of B. fragilis in clinical specimens and to facilitate surveillance of antimicrobial-resistant strains.

  8. [Investigations of some metachrome-yellow-preparations as an basic ingredient for metachromgelb-wasserblau-laktose-agar (Gassners medium) (author's transl)].

    PubMed

    Mayer, H; Schindler, S; Weisser, W

    1975-01-01

    Experiments with 5 commercial- and 4 testpreparations of Metachrome Yellow have been conducted. Results of this investigations show that the value of Gassners Medium is depending on the quality of the inhibitory substance. The microbiologically active substance (inhibition of grampositive bacteria and prevention of swarming of Proteus) was chemically identified as "Beizengelb GT Color Index 14025" correlating with CI Mordant Yellow I. Test sample II of CHROMA-GESELL-SCHAFT, STUTTGART is recommended as the best "Metachrom-Yellow for preparation of Gassners-Medium Now. Presumable this medium was modified repeatedly after its introduction in bacteriology in 1918 by Gassner. This can be an explanation for the different evaluations of Gassners medium and also for the numerous experiments which have been conducted to modify the medium. Indentity control of chemicals used in microbiology is done by thin layer and paper chromatography. This control should be done in cooperation with chemists more frequently than before.

  9. Accelerated and safe proliferation of human adipose-derived stem cells in medium supplemented with human serum.

    PubMed

    Josh, Fonny; Kobe, Kyoko; Tobita, Morikuni; Tanaka, Rica; Suzuki, Koji; Ono, Kasumi; Hyakusoku, Hiko; Mizuno, Hiroshi

    2012-01-01

    Adipose-derived stem cells (ASCs) are a promising cell source and are being investigated for a variety of therapeutic applications. However, standard expansion protocols use fetal bovine serum (FBS) as a growth factor supplement, which is a potential source of undesirable xenogeneic pathogens. For clinical safety, autologous human serum (HS) would be more appropriate. This study compared FBS-supplemented and HS-supplemented media for their enhancement of the proliferation and differentiation potential of human ASCs (hASCs). HS was obtained from the blood of 8 healthy volunteers using collection devices specially designed to derive growth factors from platelets. Growth factors in HS or FBS were measured with enzyme-linked immunosorbent assays. The hASCs were isolated with an established protocol from discarded human fat tissues obtained during a medical procedure and cultured in a medium supplemented with either 10% HS or 10% FBS. The hASCs were collected at several time points for the proliferation assays. The capacity for differentiation into the osteogenic, chondrogenic and adipogenic lineages was assessed qualitatively with the histochemical stains von Kossa, Alcian blue, and Oil red O, respectively, and quantitatively with the qualitative reverse transcriptase polymerase chain reaction. Differences in cell surface marker expression between the HS-supplemented and FBS-supplemented cultures were examined with flow cytometric analysis. Proliferation assays showed that the growth of hASCs was more rapid in HS-supplemented medium than in FBS-supplemented medium. All cells grown in each medium expressed similar patterns of cell surface markers. The ASCs cultured in the HS-supplemented medium proliferated more rapidly than those cultured in the FBS-supplemented medium and retained their differentiation capacity and immunophenotype. These results support the establishment of a safe and rapid expansion protocol with autologous serum for cell-based therapies, such as

  10. Enhancing Aerobic Growth of Campylobacter in Media Supplemented with Organic Acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of agar and sodium bicarbonate (NaHCO3) concentration on aerobic growth of Campylobacter in was determined. A fumarate-pyruvate medium was supplemented with 0.0 to 0.2% agar and inoculated with Campylobacter coli, Campylobacter fetus, or Campylobacter jejuni. Portions of the inoculated me...

  11. Supplementation of strontium to a chondrogenic medium promotes chondrogenic differentiation of human dedifferentiated fat cells.

    PubMed

    Okita, Naoya; Honda, Yoshitomo; Kishimoto, Naotaka; Liao, Wen; Azumi, Eiko; Hashimoto, Yoshiya; Matsumoto, Naoyuki

    2015-05-01

    Dedifferentiated fat cells (DFAT cells) isolated from adipose tissue have been demonstrated to differentiate into chondrogenic cells in vitro. Nevertheless, an efficient method to facilitate its chondrogenic differentiation is still unexplored, hampering the extensive application of these cells in cartilage regeneration therapies. Here we provide the evidence that supplementation of strontium ions (Sr) in a chondrogenic medium (CM) significantly promotes early chondrogenic differentiation of DFAT cells. Human DFAT cells and the mesenchymal stem cell line (RCB2153) were subjected to the CM supplemented with/without Sr. After 14 days, alcian blue staining intensity significantly increased in DFAT cells, but not in RCB2153, subjected to CM with Sr. mRNA expression analysis revealed that the CM with 1.5 mM Sr increased the expression of chondrogenic marker, collagen type 2 alpha 1, whereas there was no significant change in osteogenic markers, collagen type 1 alpha 1, runt-related transcription factor 2, and osteocalcin, and hypertrophic chondrogenic marker, collagen type 10 alpha 1. Inhibitors for extracellular signal-regulated kinase 1/2 (ERK1/2), Akt, and calcium-sensing receptor (CaSR) pathways significantly diminished the alcian blue staining intensity, providing the first evidence that these signal pathways are associated with chondrogenic differentiation of DFAT cells. CaSR and ERK1/2 pathways independently induced Sr-mediated early chondrogenic differentiation. These results suggest that Sr supplementation into the CM may provide a powerful platform for preparing chondrogenically differentiated DFAT cells for cartilage regeneration.

  12. Prospective Comparison of a New Chromogenic Medium, MRSASelect, to CHROMagar MRSA and Mannitol-Salt Medium Supplemented with Oxacillin or Cefoxitin for Detection of Methicillin-Resistant Staphylococcus aureus

    PubMed Central

    Stoakes, Luba; Reyes, Romina; Daniel, Janis; Lennox, Gwen; John, Michael A.; Lannigan, Robert; Hussain, Zafar

    2006-01-01

    MRSASelect agar was compared to CHROMagar, mannitol-salt agar with oxacillin, and mannitol-salt agar with cefoxitin (MSA-CFOX) for the isolation of methicillin-resistant Staphylococcus aureus (MRSA). The sensitivities and specificities were 97.3% and 99.8%, 82.9% and 99.1%, 80.2% and 79%, and 99.1% and 84.8%, respectively. MSA-CFOX and MRSASelect had a high sensitivity. MRSASelect, however, was more specific and proved to be a more reliable and rapid medium for the detection of MRSA. PMID:16455933

  13. Agar disk diffusion (Bauer-Kirby) tests with various fastidious and nonfastidious reference (ATCC) strains: comparison of several agar media.

    PubMed

    Traub, W H; Leonhard, B

    1994-01-01

    Several agar media (Mueller-Hinton agar, MHA; diagnostic sensitivity test agar, DSTA; Schaedler agar, SchA; Todd-Hewitt agar with added yeast extract, THYA; Wilkins-Chalgren agar, WCA) were compared using the Bauer-Kirby agar disk diffusion test against six nonfastidious quality control strains: Staphylococcus aureus ATCC 25923 and ATCC 29213, Escherichia coli ATCC 25922 and ATCC 35218, Pseudomonas aeruginosa ATCC 27853, and Enterococcus faecalis ATCC 29212. MHA, DSTA, and THYA yielded essentially comparable inhibition zones. However, WCA and SchA antagonized cotrimoxazole and aminoglycoside antibiotics; furthermore, SchA antagonized polymyxin B, and both WCA and SchA antagonized imipenem against the P. aeruginosa strain, but not against the E. coli strains. Sheep blood-MHA (Bl-MHA), WCA, THYA, and DSTA were examined with Streptococcus pyogenes ATCC 19615, Streptococcus agalactiae ATCC 13813, and Streptococcus pneumoniae ATCC 6306. In comparison with Bl-MHA, both WCA and THYA yielded comparable inhibition zones against S. pyogenes; DSTA afforded suboptimal growth. DSTA yielded larger inhibition zones with the majority of antimicrobial drugs against S. agalactiae, whereas WCA and THYA enhanced the activity of oxacillin and penicillin G against this strain. S. pneumoniae strain ATCC 6306 grew well on Bl-MHA, yielded suboptimal growth on WCA and faint growth on THYA, and failed to grow on DSTA. Chocolate-supplemented sheep blood-MHA (CHOC-MHA) was compared with Haemophilus test medium (HTM), WCA with added NAD, and THYA with added hematin and NAD against Haemophilus influenzae strains ATCC 35056 and ATCC 49247. The activities of doxycycline and rifampin were enhanced against both strains by HTM, WCA+NAD, and THYA+hematin+NAD. Only WCA+NAD antagonized cotrimoxazole against both H. influenzae strains, an effect due to thymidine; however, HTM antagonized cotrimoxazole against S. aureus ATCC 25923 and E. coli ATCC 25922. It was concluded that Bl-MHA performed best for

  14. Conifer somatic embryogenesis: improvements by supplementation of medium with oxidation-reduction agents.

    PubMed

    Pullman, Gerald S; Zeng, Xiaoyan; Copeland-Kamp, Brandi; Crockett, Jonathan; Lucrezi, Jacob; May, Sheldon W; Bucalo, Kylie

    2015-02-01

    A major barrier to the commercialization of somatic embryogenesis technology in loblolly pine (Pinus taeda L.) is recalcitrance of some high-value crosses to initiate embryogenic tissue (ET) and continue early-stage somatic embryo growth. Developing initiation and multiplication media that resemble the seed environment has been shown to decrease this recalcitrance. Glutathione (GSH), glutathione disulfide (GSSG), ascorbic acid and dehydroascorbate analyses were performed weekly throughout the sequence of seed development for female gametophyte and zygotic embryo tissues to determine physiological concentrations. Major differences in stage-specific oxidation-reduction (redox) agents were observed. A simple bioassay was used to evaluate potential growth-promotion of natural and inorganic redox agents added to early-stage somatic embryo growth medium. Compounds showing statistically significant increases in early-stage embryo growth were then tested for the ability to increase initiation of loblolly pine. Low-cost reducing agents sodium dithionite and sodium thiosulfate increased ET initiation for loblolly pine and Douglas fir (Mirb) Franco. Germination medium supplementation with GSSG increased somatic embryo germination. Early-stage somatic embryos grown on medium with or without sodium thiosulfate did not differ in GSH or GSSG content, suggesting that sodium thiosulfate-mediated growth stimulation does not involve GSH or GSSG. We have developed information demonstrating that alteration of the redox environment in vitro can improve ET initiation, early-stage embryo development and somatic embryo germination in loblolly pine.

  15. Mupirocin-mucin agar for selective enumeration of Bifidobacterium bifidum.

    PubMed

    Pechar, Radko; Rada, Vojtech; Parafati, Lucia; Musilova, Sarka; Bunesova, Vera; Vlkova, Eva; Killer, Jiri; Mrazek, Jakub; Kmet, Vladimir; Svejstil, Roman

    2014-11-17

    Bifidobacterium bifidum is a bacterial species exclusively found in the human intestinal tract. This species is becoming increasingly popular as a probiotic organism added to lyophilized products. In this study, porcine mucin was used as the sole carbon source for the selective enumeration of B. bifidum in probiotic food additives. Thirty-six bifidobacterial strains were cultivated in broth with mucin. Only 13 strains of B. bifidum utilized the mucin to produce acids. B. bifidum was selectively enumerated in eight probiotic food supplements using agar (MM agar) containing mupirocin (100 mg/L) and mucin (20 g/L) as the sole carbon source. MM agar was fully selective if the B. bifidum species was presented together with Bifidobacterium animalis subsp. lactis, Bifidobacterium breve, and Bifidobacterium longum subsp. longum species and with lactic acid bacteria (lactobacilli, streptococci). Isolated strains of B. bifidum were identified using biochemical, PCR, MALDI-TOF procedures and 16S rRNA gene sequencing. The novel selective medium was also suitable for the isolation of B. bifidum strains from human fecal samples.

  16. Use of Dorset egg medium for maintenance and transport of Neisseria meningitidis and Haemophilus influenzae type b.

    PubMed

    Wasas, A D; Huebner, R E; Klugman, K P

    1999-06-01

    Studies of bacterial meningitis are hampered by the inability to maintain the viability of etiological agents during transport to reference laboratories. The long-term survival rate of 20 isolates of Neisseria meningitidis and Haemophilus influenzae type b (Hib) on Dorset egg medium, supplemented Columbia agar base medium, chocolate agar, and Amies medium was compared with that on 70% GC agar (chocolate) transport medium. N. meningitidis isolates were also inoculated onto 5% horse blood agar, and Hib was inoculated onto Haemophilus test medium. All of the N. meningitidis isolates remained viable on Dorset egg medium for 21 days; viability on the other media was poor after only 7 days. Recovery rates of Hib isolates were similar on Dorset egg and Haemophilus test media (100% after 21 days) and significantly better than on the other media. Dorset egg medium is inexpensive and easy to make and may be invaluable for studies of bacterial meningitis in developing countries.

  17. Development of Culture Medium for the Isolation of Flavobacterium and Chryseobacterium from Rhizosphere Soil

    PubMed Central

    Nishioka, Tomoki; Elsharkawy, Mohsen Mohamed; Suga, Haruhisa; Kageyama, Koji; Hyakumachi, Mitsuro; Shimizu, Masafumi

    2016-01-01

    An effective medium designated phosphate separately autoclaved Reasoner’s 2A supplemented with cycloheximide and tobramycin (PSR2A-C/T) has been developed for the isolation of Flavobacterium and Chryseobacterium strains from the plant rhizosphere. It consists of Reasoner’s 2A agar (R2A) prepared by autoclaving phosphate and agar separately and supplementing with 50 mg L−1 cycloheximide and 1 mg L−1 tobramycin. A comparison was made among the following nine media: PSR2A-C/T, PSR2A-C/T supplemented with NaCl, R2A agar, R2A agar supplemented with cycloheximide and tobramycin, 1/4-strength tryptic soy agar (TSA), 1/10-strength TSA, soil-extract agar, Schaedler anaerobe agar (SAA), and SAA supplemented with gramicidin, for the recovery of Flavobacterium and Chryseobacterium strains from the Welsh onion rhizosphere. Flavobacterium strains were only isolated on PSR2A-C/T, and the recovery rate of Chryseobacterium strains was higher from PSR2A-C/T than from the eight other media. In order to confirm the effectiveness of PSR2A-C/T, bacteria were isolated from onion rhizosphere soil with this medium. Flavobacterium and Chryseobacterium strains were successfully isolated from this sample at a similar rate to that from the Welsh onion rhizosphere. PMID:27098502

  18. A critical synopsis: Continuous growth of proximal tubular kidney epithelial cells in hormone-supplemented serum-free medium

    NASA Technical Reports Server (NTRS)

    Chuman, L. M.; FINE; COHEN; Saier, M. H.

    1985-01-01

    The kidney forms urine and reabsorbs electrolytes and water. Kidney cell lines and hormone supplemented serum free medium were used for growth. The hormones were insulin, transferrin, vasopressin, cholesterol, prostaglandins, hydrocortisone, and triidothyronine. Epithelial cell lines are polar and form hemicysts. The Madin-Darby canine kidney(MDCK) cell line used is distal tubulelike. LLC-PK sub 1 cells are derived from pig kidneys and have the properties of different kidney segments. The LLC-PK sub 1 cells with proximal tubule properties were maintained in hormone-supplemented serum free medium. Seven factors (the aforementioned homrones and selenium) were needed for growth. Hormone-defined medium supported LLC-PK sub 1 cell growth, allowed transport (as seen by hemicyst formation), and influenced cell morphology. Vasopressin (used for growth and morphology) could be partially replaced by isobutylmethylxanthine or dibutyryl cAMP. The defined medium was used to isolate rabbit proximal tubule kidney epithelial cells free of fibroblasts.

  19. Dietary supplementation with medium-chain TAG has long-lasting cognition-enhancing effects in aged dogs.

    PubMed

    Pan, Yuanlong; Larson, Brian; Araujo, Joseph A; Lau, Winnie; de Rivera, Christina; Santana, Ruben; Gore, Asa; Milgram, Norton W

    2010-06-01

    The present study focused on the hypothesis that dietary supplementation with medium-chain TAG (MCT) will improve cognitive function in aged dogs by providing the brain with energy in the form of ketones. Aged Beagle dogs were subjected to a baseline battery of cognitive tests, which were used to establish cognitively equivalent control or treatment groups. The dogs in the treatment group were maintained on a diet supplemented with 5.5 % MCT. After an initial wash-in period, all the dogs were tested with a battery of cognitive test protocols, which assessed sequentially landmark discrimination learning ability, egocentric visuospatial function and attention. The groups were maintained on the diets for 8 months. The MCT-supplemented group showed significantly better performance in most of the test protocols than the control group. The group differences also varied as a function of task difficulty, with the more difficult task showing greater supplementation effects than the easier tasks. The group given the MCT supplement showed significantly elevated levels of beta-hydroxybutyrate, a ketone body. These results indicate, first, that long-term supplementation with MCT can have cognition-improving effects, and second, that MCT supplementation increases circulating levels of ketones. The results support the hypothesis that brain function of aged dogs can be improved by MCT supplementation, which provides the brain with an alternative energy source.

  20. Oral supplementation of medium-chain fatty acids during the dry period supports the neutrophil viability of peripartum dairy cows.

    PubMed

    Piepers, Sofie; De Vliegher, Sarne

    2013-08-01

    A randomised clinical trial was conducted to explore the effect of orally supplemented medium-chain fatty acids (MCFA) to heifers and cows starting 6-8 weeks prior to expected calving date on blood and milk polymorphonuclear neutrophilic leucocyte (PMNL) apoptosis between 1 and 3 d in milk (DIM). The effects of MCFA-supplementation on the likelihood of intramammary infections (IMI) in early lactation, and test-day somatic cell count (SCC) and average daily milk yield (MY) during the first 4 months of lactation were evaluated as well. Twenty-two animals were included of which half were orally supplemented with MCFA starting 6-8 weeks prior to calving and half served as non-supplemented controls. The PMNL viability in both blood and milk was quantified using dual-colour flow cytometry with fluorescein-labelled annexin and propidium iodide. In non-supplemented animals, % blood PMNL apoptosis significantly increased between start of supplementation and early lactation, reflecting a potential reduction in innate immune capacity, whereas this was not true in the MCFA-supplemented animals. Similar results were seen in milk PMNL apoptosis. Overall, the % apoptotic milk PMNL between 1 and 3 DIM was significantly lower in the MCFA-supplemented group compared with the non-supplemented group. There was no substantial effect of oral MCFA-supplementation on the likelihood of quarter IMI nor on the composite test-day milk SCC or average daily MY. In conclusion, oral MCFA-supplementation starting 6-8 weeks before expected calving date supported the blood and milk neutrophil viability in early lactating dairy cows. Still, this was not reflected in an improvement of udder health nor MY in early and later lactation. The results should trigger research to further unravel the mechanisms behind the observed immunomodulating effect, and the potential relevance for the cows' performances throughout lactation.

  1. Improving agar electrospinnability with choline-based deep eutectic solvents.

    PubMed

    Sousa, Ana M M; Souza, Hiléia K S; Uknalis, Joseph; Liu, Shih-Chuan; Gonçalves, Maria P; Liu, LinShu

    2015-09-01

    Very recently our group has produced novel agar-based fibers by an electrospinning technique using water as solvent and polyvinyl alcohol (PVA) as co-blending polymer. Here, we tested the deep eutectic solvent (DES), (2-hydroxyethyl)trimethylammonium chloride/urea prepared at 1:2 molar ratio, as an alternative solvent medium for agar electrospinning. The electrospun materials were collected with an ethanol bath adapted to a previous electrospinning set-up. One weight percent agar-in-DES showed improved viscoelasticity and hence, spinnability, when compared to 1 wt% agar-in-water and pure agar nanofibers were successfully electrospun if working above the temperature of sol-gel transition (∼80 °C). By changing the solvent medium we decreased the PVA concentration (5 wt% starting solution) and successfully produced composite fibers with high agar contents (50/50 agar/PVA). Best composite fibers were formed with the 50/50 and 30/70 agar/PVA solutions. These fibers were mechanically resistant, showed tailorable surface roughness and diverse size distributions, with most of the diameters falling in the sub-micron range. Both nano and micro forms of agar fibers (used separately or combined) may have potential for the design of new and highly functional agar-based materials.

  2. Performance of the EUCAST disk diffusion method, the CLSI agar screen method, and the Vitek 2 automated antimicrobial susceptibility testing system for detection of clinical isolates of Enterococci with low- and medium-level VanB-type vancomycin resistance: a multicenter study.

    PubMed

    Hegstad, Kristin; Giske, Christian G; Haldorsen, Bjørg; Matuschek, Erika; Schønning, Kristian; Leegaard, Truls M; Kahlmeter, Gunnar; Sundsfjord, Arnfinn

    2014-05-01

    Different antimicrobial susceptibility testing methods to detect low-level vancomycin resistance in enterococci were evaluated in a Scandinavian multicenter study (n=28). A phenotypically and genotypically well-characterized diverse collection of Enterococcus faecalis (n=12) and Enterococcus faecium (n=18) strains with and without nonsusceptibility to vancomycin was examined blindly in Danish (n=5), Norwegian (n=13), and Swedish (n=10) laboratories using the EUCAST disk diffusion method (n=28) and the CLSI agar screen (n=18) or the Vitek 2 system (bioMérieux) (n=5). The EUCAST disk diffusion method (very major error [VME] rate, 7.0%; sensitivity, 0.93; major error [ME] rate, 2.4%; specificity, 0.98) and CLSI agar screen (VME rate, 6.6%; sensitivity, 0.93; ME rate, 5.6%; specificity, 0.94) performed significantly better (P=0.02) than the Vitek 2 system (VME rate, 13%; sensitivity, 0.87; ME rate, 0%; specificity, 1). The performance of the EUCAST disk diffusion method was challenged by differences in vancomycin inhibition zone sizes as well as the experience of the personnel in interpreting fuzzy zone edges as an indication of vancomycin resistance. Laboratories using Oxoid agar (P<0.0001) or Merck Mueller-Hinton (MH) agar (P=0.027) for the disk diffusion assay performed significantly better than did laboratories using BBL MH II medium. Laboratories using Difco brain heart infusion (BHI) agar for the CLSI agar screen performed significantly better (P=0.017) than did those using Oxoid BHI agar. In conclusion, both the EUCAST disk diffusion and CLSI agar screening methods performed acceptably (sensitivity, 0.93; specificity, 0.94 to 0.98) in the detection of VanB-type vancomycin-resistant enterococci with low-level resistance. Importantly, use of the CLSI agar screen requires careful monitoring of the vancomycin concentration in the plates. Moreover, disk diffusion methodology requires that personnel be trained in interpreting zone edges.

  3. Supplementation of bovine embryo culture medium with L-arginine improves embryo quality via nitric oxide production.

    PubMed

    Santana, Priscila Di Paula Bessa; Silva, Thiago Velasco Guimarães; da Costa, Nathália Nogueira; da Silva, Bruno Barauna; Carter, Timothy Frederick; Cordeiro, Marcela da Silva; da Silva, Bruno José Martins; Santos, Simone do Socorro Damasceno; Herculano, Anderson Manoel; Adona, Paulo Roberto; Ohashi, Otávio Mitio; Miranda, Moysés dos Santos

    2014-10-01

    Nitric oxide (NO) is a cell-signaling molecule that regulates a variety of molecular pathways. We investigated the role of NO during preimplantation embryonic development by blocking its production with an inhibitor or supplementing in vitro bovine embryo cultures with its natural precursor, L-arginine, over different periods. Endpoints evaluated included blastocyst rates, development kinetics, and embryo quality. Supplementation with the NO synthase inhibitor N-Nitro-L-arginine-methyl ester (L-NAME) from Days 1 to 8 of culture decreased blastocyst (P < 0.05) and hatching (P < 0.05) rates. When added from Days 1 to 8, 50 mM L-arginine decreased blastocyst rates (P < 0.001); in contrast, when added from Days 5 to 8, 1 mM L-arginine improved embryo hatching rates (P < 0.05) and quality (P < 0.05) as well as increased POU5F1 gene expression (P < 0.05) as compared to the untreated control. Moreover, NO levels in the medium during this culture period positively correlated with the increased embryo hatching rates and quality (P < 0.05). These data suggest exerts its positive effects during the transition from morula to blastocyst stage, and that supplementing the embryo culture medium with L-arginine favors preimplantation development of bovine embryos.

  4. Milk fat responses to dietary supplementation of short- and medium-chain fatty acids in lactating dairy cows.

    PubMed

    Vyas, D; Teter, B B; Erdman, R A

    2012-09-01

    Short-and medium-chain fatty acids (SMCFA), which are synthesized de novo in the mammary gland, are reduced to a much greater extent than the long-chain fatty acids during diet-induced milk fat depression. Our hypothesis was that SMCFA are limiting for milk fat synthesis even under conditions when milk fat is not depressed. Our objective was to test the potential limitation of SMCFA on milk fat synthesis via dietary supplementation. Sixteen lactating Holstein cows (107±18 d in milk) were fed a corn silage-based total mixed ration. Cows were randomly assigned to groups of 4 per pen and supplemented with 1 of 4 dietary fat supplements (600 g/d) supplied in a 4×4 Latin square design with 21-d experimental periods. Treatments consisted of fat supplements containing mixtures of calcium salts of long-chain fatty acids (Megalac; Church & Dwight Co. Inc., Princeton, NJ) and an SMCFA mixture (S; 3.3% C8, 7.6% C10, 9.85% C12, 32.12% C14, and 47.11% C16) that contained 0, 200, 400, and 600 g/d of S substituted for Megalac (S0, S200, S400, and S600, respectively). No treatment effects were observed for dry matter and fat-corrected milk. However, milk yield was decreased with S600. Milk fat increased linearly by 0.17, 0.25, and 0.33 percentage units for the respective S treatments. However, fat yield peaked at S200 and milk protein concentration and yield was significantly decreased at the higher S levels because of a linear trend toward decreased milk yield in the S600 treatment. In conclusion, SMCFA supplementation linearly increased milk fat concentration but decreased milk production at the higher levels of supplementation. The dietary inclusion of SMCFA had no effects on total milk fat yield.

  5. The effect of supplementation of amino acids and taurine to modified KSOM culture medium on rat embryo development.

    PubMed

    Nakamura, Kazuomi; Morimoto, Kayoko; Shima, Kaoru; Yoshimura, Yuki; Kazuki, Yasuhiro; Suzuki, Osamu; Matsuda, Junichiro; Ohbayashi, Tetsuya

    2016-11-01

    The rat is widely used as a laboratory animal for research. In particular, genetically engineered rats are essential for production of animal models of several diseases. Although embryo manipulation techniques are needed to produce them, such technology for rat preimplantation embryos is not as advanced as it is for mouse embryos. One reason is that in vitro culture systems for preimplantation embryos are limited in rats. Therefore, we intended to develop a new culture system for rat preimplantation embryos focusing on supplementation of amino acids as nutrition to the culture media. First, we found that taurine, glycine, glutamate, and alanine were abundant in the oviductal fluid of Wistar rats. The profile of taurine and these three amino acids was unchanged during the estrous cycle and from Days 0 to 3 of pregnancy (Day 0; vaginal plug was confirmed). Second, we assessed the effect of phosphate and phenol red on the development of rat zygotes and confirmed that they caused two-cell block. Third, we examined the effect of changing the medium on zygote development because addition of amino acids into culture medium causes ammonium accumulation, which is detrimental to embryo development. Blastocyst formation was suppressed in cultures with no medium change (P = 0.004; decreased to approximately one-fourth of that with medium change). Fourth, we examined the effect of supplementation of these three amino acids and taurine to modified potassium simplex optimized medium (KSOM). The zygote development rates were increased by the three amino acids and taurine in a concentration-dependent manner at 48, 72, and 96 hours (P = 0.001, 0.005, and 0.009, respectively) in culture. Finally, we confirmed that blastocysts cultured in modified KSOM had the capacity to develop to full term after implantation. These results showed that not only the supply of nutrients but also removal of wastes and toxicants is important for culture of rat preimplantation embryos.

  6. Electro-osmosis in gels: Application to Agar-Agar

    NASA Astrophysics Data System (ADS)

    Cherblanc, Fabien; Boscus, Jérôme; Bénet, Jean-Claude

    2008-10-01

    Widely used in food- and bio-engineering as a reference material, Agar-Agar gel is the focus of an experimental investigation concerning the electro-osmosis phenomenon. After presenting the experimental methods, one trial is discussed in detail. A fair reproducibility of results is obtained, and the averaged electro-osmotic permeability is provided. This value lies in the range generally measured on various kind of soils, even if Agar-Agar gel does not share any micro-structural characteristics with soils. To cite this article: F. Cherblanc et al., C. R. Mecanique 336 (2008).

  7. Predictors of Student Success in Supplemental Instruction Courses at a Medium Sized Women's University

    ERIC Educational Resources Information Center

    Lindsay, Keston; Carlsen-Landy, Bev; Boaz, Cammy; Marshall, David

    2017-01-01

    Supplemental Instruction (SI) is a program that seeks to improve student success by targeting classes with high failure rates, as defined with a failure percentage of 30% or more. It is organized by an administrative SI supervisor who supervises SI leaders, which are students that have successfully completed the courses that they have been…

  8. Supplementation of an Artificial Medium for the Parasitoid Exorista larvarum (Diptera: Tachnidae) With Hemolymph of Hermetia illucens (Diptera: Stratiomyidae) or Antheraea pernyi (Lepidoptera: Saturniidae).

    PubMed

    Dindo, Maria Luisa; Vandicke, Jonas; Marchetti, Elisa; Spranghers, Thomas; Bonte, Jochem; De Clercq, Patrick

    2016-04-01

    The effect of supplementing hemolymph of the black soldier fly, Hermetia illucens (L.), or the Chinese oak silkworm, Antheraea pernyi (Guérin-Méneville), to a basic insect-free artificial medium for the tachinid Exorista larvarum (L.) was investigated. The supplementation (20% w/w) was based on the assumption that insect additives may optimize the media for this parasitoid. Egg hatch, pupal and adult yields, and sex ratio did not differ among the enriched and basic media. Preimaginal development was faster on both hemolymph-enriched media than on the basic medium. Despite the shorter development on the medium supplemented with H. illucens hemolymph than on the basic medium, on the two media puparium weights were comparable. The female flies reared on the medium enriched with H. illucens hemolymph did not lay more eggs, but the latter yielded significantly more puparia compared with the control females. Conversely, the medium enriched with A. pernyi hemolymph yielded lower female puparium weights than the basic medium and produced only one ovipositing female out of the five obtained female adults. These results indicate that the in vitro development of E. larvarum improved when the basic artificial medium was enriched with H. illucens hemolymph, whereas the supplementation with A. pernyi hemolymph negatively affected the quality of the in vitro-reared females.

  9. Gravimorphogenesis in agarics.

    PubMed

    Moore, D; Hock, B; Greening, J P; Kern, V D; Novak Frazer, L; Monzer, J

    1996-03-01

    The shape changes which occur in agaric fruit bodies in response to change in the direction of gravity, usually referred to as gravitropism are morphogenetic changes. Our interest in what we prefer to call gravimorphogenesis is to use it to examine morphogenesis experimentally. We are examining two agarics, Coprinus cinereus and Flammulina velutipes, and applying the best available technologies, including video analysis, all forms of electron microscopy, computer-aided image analysis and experiments in orbit in Spacelab. Responses to gravity of the two organisms differ in ways which can be related to their ecological and structural adaptations. C. cinereus reacts extremely rapidly; its fruit body can regain the vertical within 3 h of being placed horizontal, whereas F. velutipes requires 12 h to bend through 90 degrees. The fungi also differ in the bulk of tissue involved in the response. In Coprinus, a zone extending several cm down from the apex is normally involved in bending. In Flammulina, gravisensing is limited to a region just a few mm immediately below the cap, although curvature is performed in a zone of up to 2 cm below. Flammulina cultures were flown on the Spacelab D-2 mission in 1993, and fruit body disorientation in orbit provides the first definitive proof that 'gravitropism' really is a response to the unidirectional gravity vector. Experiments with different clinostat rotation rates in Flammulina indicate that the perception threshold is about 10(-4) x g. Analysis of different times of exposure to an altered gravity vector prior to clinorotation in Coprinus reveals that the perception time is 7 minutes and that continued response requires continued exposure. Cell size determinations in Coprinus demonstrate that cells of the stem increase in length, not diameter, to produce the growth differential. In Flammulina a unique population of highly electron-transparent microvacuoles changes in distribution; decreasing in upper cells and increasing in the

  10. Ecdysteroids in Axenically Propagated Caenorhabditis elegans and Culture Medium

    PubMed Central

    Chitwood, D. J.; Feldlaufer, M. F.

    1990-01-01

    Ecdysteroids (insect molting hormones) from Caenorhabditis elegans were chromatographically purified and quantified by radioimmunoassay. Nematodes from semidefined medium contained the immunoreactive equivalent of 460 pg ecdysone per gram dry weight. Culture medium, however, contained the immunoreactive equivalent of 68 times the quantity within the nematodes. In a defined medium lacking immunoreactivity, C. elegans contained 520 pg ecdysone equivalents per gram dry weight but reproduced slowly. Reproduction of C. elegans in defined medium was enhanced by formulation in agar. Propagation of C. elegans in either agar-based or aqueous defined medium supplemented with [¹⁴C]cholesterol of high specific activity failed to result in production of radiolabeled free ecdysteroids or polar or apolar ecdysteroid conjugates. Failure to demonstrate ecdysteroid biosynthesis in C. elegans raises questions about the ecdysteroids identified previously in nematodes being products of endogenous biosynthesis, a necessary condition for these compounds to be nematode hormones. PMID:19287765

  11. 21 CFR 184.1115 - Agar-agar.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Agar-agar. 184.1115 Section 184.1115 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) DIRECT FOOD SUBSTANCES AFFIRMED AS GENERALLY RECOGNIZED AS SAFE Listing of...

  12. Supplementation of insulin-transferrin-selenium to embryo culture medium improves the in vitro development of pig embryos.

    PubMed

    Das, Ziban Chandra; Gupta, Mukesh Kumar; Uhm, Sang Jun; Lee, Hoon Taek

    2014-08-01

    Insulin, transferrin and selenium (ITS) supplementation to oocyte maturation medium improves the post-fertilization embryonic development in pigs. ITS is also commonly used as a supplement for the in vitro culture (IVC) of embryos and stem cells in several mammalian species. However, its use during IVC of pig embryos has not been explored. This study investigated the effect of ITS supplementation to IVC medium on the in vitro development ability of pig embryos produced by parthenogenetic activation (PA), in vitro fertilization (IVF) or somatic cell nuclear transfer (SCNT). We observed that ITS had no significant effect on the rate of first cleavage (P > 0.05). However, the rate of blastocyst formation in ITS-treated PA (45.3 ± 1.9 versus 27.1 ± 2.3%), IVF (31.6 ± 0.6 versus 23.5 ± 0.6%) and SCNT (17.6 ± 2.3 versus 10.7 ± 1.4%) embryos was significantly higher (P < 0.05) than those of non-treated controls. Culture of PA embryos in the presence of ITS also enhanced the expansion and hatching ability (29.1 ± 3.0 versus 18.2 ± 3.8%; P < 0.05) of blastocysts and increased the total number of cells per blastocyst (53 ± 2.5 versus 40.9 ± 2.6; P < 0.05). Furthermore, the beneficial effect of ITS on PA embryos was associated with significantly reduced level of intracellular reactive oxygen species (ROS) (20.0 ± 2.6 versus 46.9 ± 3.0). However, in contrast to PA embryos, ITS had no significant effect on the blastocyst quality of IVF and SCNT embryos (P > 0.05). Taken together, these data suggest that supplementation of ITS to the IVC medium exerts a beneficial but differential effect on pig embryos that varies with the method of embryo production in vitro.

  13. Effect of Medium Supplements on Agrobacterium rhizogenes Mediated Hairy Root Induction from the Callus Tissues of Camellia sinensis var. sinensis

    PubMed Central

    Rana, Mohammad M.; Han, Zhuo-Xiao; Song, Da-Peng; Liu, Guo-Feng; Li, Da-Xiang; Wan, Xiao-Chun; Karthikeyan, Alagarsamy; Wei, Shu

    2016-01-01

    Tea (Camellia sinensis L.) is recalcitrant to Agrobacterium-mediated genetic transformation largely due to the bactericidal effects of tea polyphenols and phenolics oxidation induced by necrosis of explant tissue over the process of transformation. In this study, different antioxidants/adsorbents were added as supplements to the co-cultivation and post co-cultivation media to overcome these problems for the transformation improvement. Tea-cotyledon-derived calli were used as explants and Agrobacterium rhizognes strain ATCC 15834 was used as a mediator. Results showed that Agrobacterium growth, virulence (vir) gene expression and browning of explant tissue were greatly influenced by different supplements. Murashige and Skoog (MS) basal salts medium supplemented with 30 g·L−1 sucrose, 0.1 g·L−1 l-glutamine and 5 g·L−1 polyvinylpolypyrrolidone (PVPP) as co-cultivation and post co-cultivation media could maintain these parameters better that ultimately led to significant improvement of hairy root generation efficiency compared to that in the control (MS + 30 g·L−1 sucrose). Additionally, the reporter genes β-glucuronidase (gusA) and cyan fluorescent protein (cfp) were also stably expressed in the transgenic hairy roots. Our study would be helpful in establishing a feasible approach for tea biological studies and genetic improvement of tea varieties. PMID:27428960

  14. Effect of genistein supplementation of thawing medium on characteristics of frozen human spermatozoa.

    PubMed

    Martinez-Soto, Juan Carlos; de DiosHourcade, Juan; Gutiérrez-Adán, Alfonso; Landeras, José Lorenzo; Gadea, Joaquín

    2010-05-01

    In this study, we evaluated the effects of genistein supplementation of the thawing extender on frozen-thawed human semen parameters. We analyzed the effect of supplementation on sperm motility, capacitation (membrane lipid disorder), reactive oxygen species (ROS) generation, chromatin condensation and DNA damage. Using this preliminary information, it maybe possible to improve the cryopreservation process and reduce the cellular damage. We have confirmed that the isoflavone genistein (10 micromol L(-1)) has antioxidant properties on the frozen-thawed spermatozoa. This results in a decreased ROS production that shows a slight improvement in the sperm motility, and decreases the membrane lipid disorder and DNA damage caused by cryopreservation. These results suggest an effect of genistein on sperm functionality that could be of interest for assisted reproduction treatments using frozen-thawed human spermatozoa, but further studies will be necessary to confirm our findings and to evaluate the possible clinical applications.

  15. Cognition and Synaptic-Plasticity Related Changes in Aged Rats Supplemented with 8- and 10-Carbon Medium Chain Triglycerides

    PubMed Central

    Wang, Dongmei; Mitchell, Ellen S.

    2016-01-01

    Brain glucose hypometabolism is a common feature of Alzheimer’s disease (AD). Previous studies have shown that cognition is improved by providing AD patients with an alternate energy source: ketones derived from either ketogenic diet or supplementation with medium chain triglycerides (MCT). Recently, data on the neuroprotective capacity of MCT-derived medium chain fatty acids (MCFA) suggest 8-carbon and 10-carbon MCFA may have cognition-enhancing properties which are not related to ketone production. We investigated the effect of 8 week treatment with MCT8, MCT10 or sunflower oil supplementation (5% by weight of chow diet) in 21 month old Wistar rats. Both MCT diets increased ketones plasma similarly compared to control diet, but MCT diets did not increase ketones in the brain. Treatment with MCT10, but not MCT8, significantly improved novel object recognition memory compared to control diet, while social recognition increased in both MCT groups. MCT8 and MCT10 diets decreased weight compared to control diet, where MCFA plasma levels were higher in MCT10 groups than in MCT8 groups. Both MCT diets increased IRS-1 (612) phosphorylation and decreased S6K phosphorylation (240/244) but only MCT10 increased Akt phosphorylation (473). MCT8 supplementation increased synaptophysin, but not PSD-95, in contrast MCT10 had no effect on either synaptic marker. Expression of Ube3a, which controls synaptic stability, was increased by both MCT diets. Cortex transcription via qPCR showed that immediate early genes related to synaptic plasticity (arc, plk3, junb, egr2, nr4a1) were downregulated by both MCT diets while MCT8 additionally down-regulated fosb and egr1 but upregulated grin1 and gba2. These results demonstrate that treatment of 8- and 10-carbon length MCTs in aged rats have slight differential effects on synaptic stability, protein synthesis and behavior that may be independent of brain ketone levels. PMID:27517611

  16. Cognition and Synaptic-Plasticity Related Changes in Aged Rats Supplemented with 8- and 10-Carbon Medium Chain Triglycerides.

    PubMed

    Wang, Dongmei; Mitchell, Ellen S

    2016-01-01

    Brain glucose hypometabolism is a common feature of Alzheimer's disease (AD). Previous studies have shown that cognition is improved by providing AD patients with an alternate energy source: ketones derived from either ketogenic diet or supplementation with medium chain triglycerides (MCT). Recently, data on the neuroprotective capacity of MCT-derived medium chain fatty acids (MCFA) suggest 8-carbon and 10-carbon MCFA may have cognition-enhancing properties which are not related to ketone production. We investigated the effect of 8 week treatment with MCT8, MCT10 or sunflower oil supplementation (5% by weight of chow diet) in 21 month old Wistar rats. Both MCT diets increased ketones plasma similarly compared to control diet, but MCT diets did not increase ketones in the brain. Treatment with MCT10, but not MCT8, significantly improved novel object recognition memory compared to control diet, while social recognition increased in both MCT groups. MCT8 and MCT10 diets decreased weight compared to control diet, where MCFA plasma levels were higher in MCT10 groups than in MCT8 groups. Both MCT diets increased IRS-1 (612) phosphorylation and decreased S6K phosphorylation (240/244) but only MCT10 increased Akt phosphorylation (473). MCT8 supplementation increased synaptophysin, but not PSD-95, in contrast MCT10 had no effect on either synaptic marker. Expression of Ube3a, which controls synaptic stability, was increased by both MCT diets. Cortex transcription via qPCR showed that immediate early genes related to synaptic plasticity (arc, plk3, junb, egr2, nr4a1) were downregulated by both MCT diets while MCT8 additionally down-regulated fosb and egr1 but upregulated grin1 and gba2. These results demonstrate that treatment of 8- and 10-carbon length MCTs in aged rats have slight differential effects on synaptic stability, protein synthesis and behavior that may be independent of brain ketone levels.

  17. Effect of antioxidant supplementation of cryopreservation medium on post-thaw integrity of human spermatozoa.

    PubMed

    Taylor, Katrina; Roberts, Peter; Sanders, Kathy; Burton, Peter

    2009-02-01

    This study examined whether the addition of an antioxidant to cryopreservation medium could improve the post-thaw integrity of cryopreserved human spermatozoa, particularly from men with abnormal semen parameters. Semen samples were collected by masturbation and assessed following WHO standards. Normal (n = 23) and abnormal (n = 20) samples were divided into three aliquots prior to cryopreservation. The first aliquot remained untreated and was mixed with cryopreservation medium (in-house 1:1). The second and third aliquots were mixed with cryopreservation medium containing either 100 micromol or 200 micromol vitamin E analogue. Samples were frozen at -10 degrees C per minute to -80 degrees C, then plunged into liquid nitrogen. Thawed samples were assessed for motility, vitality and DNA integrity. Split-plot repeated-measures ANOVA was used to assess within-subject (dose) and between-group (normal/abnormal) differences in post-thaw motility index, vitality staining and DNA fragmentation. Vitamin E dose was significantly associated with post-thaw motility (P = 0.041) and the pattern of response across doses was similar for normal and abnormal groups. Post-thaw motility was significantly improved by the addition of 200 micromol vitamin E (P = 0.006), but neither vitality nor sperm DNA fragmentation were altered. These results suggest that the addition of vitamin E to cryopreservation medium improves post-thaw motility.

  18. Motility-indole-lysine medium for presumptive identification of enteric pathogens of Enterobacteriaceae.

    PubMed

    Reller, L B; Mirrett, S

    1975-09-01

    Detection of lysine decarboxylase activity is a useful supplement to reactions on triple sugar-iron (TSI) and urea agars in the initial examination of suspected pathogenic isolates from fecal cultures. Owing to the added value of motility and indole production in the differentiation of enteric pathogens, we prepared and evaluated a motility-indole-lysine (MIL) medium. The following 890 organisms were tested: 264 Shigella, 2 Edwardsiella, 182 Salmonella enteritidis, 235 S. typhi, 3 Arizona, 32 Yersinia enterocolitica, and 172 other members of the family Enterobacteriaceae. With few exceptions the MIL medium gave the same results as the standard motility, indole, and lysine decarboxylase (Moeller) test media. All discrepancies were with the indole reaction, which was weak in 2 of 67 strains of Escherichia coli and falsely negative in 6 of 32 strains of Y. enterocolitica. When both TSI agar and lysine-iron agar (LIA) slants are used in the evaluation isolates from fecal cultures, detection of H2S is duplicated. Both LIA and MIL medium detect lysine decarboxylase and deaminase activity equally well. Because of its ability to detect motility and indole production, the MIL medium is more useful than LIA when used with TSI agar. The combination of TSI agar, MIL medium, and urea agar enables reliable initial recognition of enteric pathogens of the Enterobacteriaceae.

  19. Performance characteristics of a diesel engine using low- and medium-energy gases as a fuel supplement (fumigation)

    NASA Technical Reports Server (NTRS)

    Monford, L. G.

    1976-01-01

    The use of low- and medium-energy gases derived from solid waste is investigated. Gases that simulate those gases that could be derived from refuse were injected into the air inlet of a 298-kilowatt (400 horsepower) diesel engine as a fuel supplement. This process is called fumigation. Three different gases with thermal-energy contents of 6.11 MJ/cu m (164 Btu/cu ft), 18.1 MJ/cu m (485 Btu/cu ft), and 18.8 MJ/cu m (505 Btu/cu ft, respectively, were used at rates ranging as high as 20 percent of the normal fuel oil energy at four different engine load points. The test results indicated approximately 100 percent gas energy utilization with no observable deleterious effect on the engine.

  20. One-step seeding of neural stem cells with vitronectin-supplemented medium for high throughput screening assays

    PubMed Central

    Dai, Sheng; Li, Rong; Long, Yan; Titus, Steve; Zhao, Jinghua; Huang, Ruili; Xia, Menghang; Zheng, Wei

    2017-01-01

    Human neuronal cells differentiated from induced pluripotent cells have emerged as a new model system for the study of disease pathophysiology and evaluation of drug efficacy. Differentiated neuronal cells are more similar in genetics and biological content to the human brain cells than other animal disease models. However, culture of neuronal cells in assay plates requires a labor-intensive procedure of plate pre-coating, hampering its applications in high throughput screening (HTS). We developed a simplified method with one-step seeding of neural stem cells in assay plates by supplementing the medium with a recombinant human vitronectin (VTN), thus avoiding plate pre-coating. Robust results were obtained from cell viability, calcium response, and neurite outgrowth assays using this new method. Our data demonstrate that this approach greatly simplifies high throughput assays using neuronal cells differentiated from human stem cells for translational research. PMID:27647668

  1. Supplementation of culture medium with L-carnitine improves development and cryotolerance of bovine embryos produced in vitro.

    PubMed

    Takahashi, Toshikiyo; Inaba, Yasushi; Somfai, Tamas; Kaneda, Masahiro; Geshi, Masaya; Nagai, Takashi; Manabe, Noboru

    2013-01-01

    High lipid content in embryos is associated with low freezing tolerance. This study assessed the effects of exogenous L-carnitine, an enhancer of lipid metabolism, on the in vitro development and freezing survival of bovine embryos. Also, effects on metabolic activity, reactive oxygen species (ROS) and apoptosis were investigated. Supplementation of embryo culture medium with 1.518 mM or 3.030 mM L-carnitine significantly increased the rates of zygote development to the blastocyst stage and blastocyst cell numbers whereas 6.072 mM of this compound did not improve embryo development. Survival rates after slow freezing of blastocysts were significantly higher when embryos were cultured in the presence of 1.518 mM or 3.030 mM L-carnitine compared with the control. A lower density of lipid droplets was detected in L-carnitine-treated blastocysts compared with the control. L-carnitine significantly reduced ROS levels in 2-cell embryos but did not reduce ROS levels at later stages. The apoptotic cell rate was not different between control and L-carnitine-treated blastocysts. L-carnitine significantly increased ATP levels in 2-cell embryos but not at the 8-cell or blastocyst stages. L-carnitine increased the expression of metabolism-related ATP6 and COX1 genes in blastocysts. In conclusion, L-carnitine supplementation enhanced lipid metabolism in embryos resulting in improved development and cryotolerance of bovine blastocysts produced in vitro.

  2. Glycerol supplementation of the growth medium enhances in situ detoxification of furfural by Clostridium beijerinckii during butanol fermentation.

    PubMed

    Ujor, Victor; Agu, Chidozie Victor; Gopalan, Venkat; Ezeji, Thaddeus Chukwuemeka

    2014-01-01

    Lignocellulose-derived microbial inhibitors such as furfural and 5-hydroxymethyl furfural adversely affect fermentation of lignocellulosic biomass hydrolysates to fuels and chemicals due to their toxicity on fermenting microbes. To harness the potential of lignocellulose as a cheap source of fermentable sugars, in situ detoxification of furfural and other lignocellulose-derived microbial inhibitors is essential. To enhance in situ detoxification and tolerance of furfural by Clostridium beijerinckii NCIMB 8052 during acetone-butanol-ethanol (ABE) fermentation, the effect of glycerol on NADH/NADPH generation and ABE production by furfural (4, 5, and 6 g/L)-challenged cultures was investigated in this study. In all instances, beneficial outcomes were observed. For example, the fermentation medium supplemented with glycerol and subjected to 5 g/L furfural elicited up to 1.8- and 3-fold increases, respectively, in NADH and NADPH levels in C. beijerinckii 8052 relative to the control culture. These critical changes are the likely underpinnings for the glycerol-mediated 2.3-fold increase in the rate of detoxification of 5 g/L furfural, substrate consumption, and ABE production compared to the unsupplemented medium. Collectively, these results demonstrate that increased intracellular NADH/NADPH in C. beijerinckii 8052 due to glycerol utilization engenders favorable effects on many aspects of cellular metabolism, including enhanced furfural reduction and increased ABE production.

  3. Lysine-iron agar in the detection of Arizona cultures.

    PubMed

    EDWARDS, P R; FIFE, M A

    1961-11-01

    A lysine-iron agar is described and recommended for the detection of Arizona strains which ferment lactose rapidly. Black colonies which appear on bismuth sulfite agar should be transferred to the medium. Salmonellae and Arizona cultures produce a distinctive reaction since they are the only recognized groups of enteric bacteria which regularly produce lysine decarboxylase rapidly and form large amounts of hydrogen sulfide. Use of the medium is particularly recommended in the examination of specimens from enteric infections in which shigellae and salmonellae are not detected.

  4. Medium for presumptive identification of Yersinia enterocolitica.

    PubMed

    Weagant, S D

    1983-02-01

    A medium, lysine-arginine-iron agar, was developed for the presumptive identification of Yersinia enterocolitica isolates. This medium was a modification of lysine-iron agar and allowed for the testing of five biochemical characteristics in a single tube medium. The reactions of Y. enterocolitica on this medium were reliable and distinctive. The medium significantly simplified the identification of Y. enterocolitica isolates.

  5. Supplementation of IVF medium with melatonin: effect on sperm functionality and in vitro produced bovine embryos.

    PubMed

    Cheuquemán, C; Arias, M E; Risopatrón, J; Felmer, R; Álvarez, J; Mogas, T; Sánchez, R

    2015-08-01

    Gamete co-incubation generates high free radical levels surrounding growing zygotes which may impair subsequent embryo viability. Melatonin eliminates a wide variety of free radicals; hence, we tried to improve in vitro embryo production by adding melatonin to in vitro fertilisation (IVF) media in high (Exp. 1) and low concentrations (Exp. 2), and we evaluated its effect on bull sperm function during IVF co-incubation time (Exp. 3). In Experiment 1, we supplemented IVF media culture with 0.01, 0.1 and 1 mmol of melatonin, along with a no melatonin control group. In Experiment 2, melatonin levels were reduced to 10, 100 and 1000 nmol, with a no melatonin control group. In Experiment 3, spermatozoa were incubated in IVF media with melatonin (as Exp. 2) and functional parameters were analysed at 0, 4 and 18 h. In Experiment 1, only 1 mmol melatonin showed lesser blastocyst rates than control (C: 23.2 ± 6.7% versus 1 mmol: 2.0 ± 1.7%). In Experiment 2, no statistical differences were found in cleavage percentage, blastocyst percentage and total cell count for any melatonin treatment. In Experiment 3, sperm samples with 1000 nmol melatonin had a significantly higher wobbler (WOB) coefficient, a lower percentage of intact acrosomes, a lower percentage of viable spermatozoa with ROS, greater DNA fragmentation and higher DNA oxidation than controls. Total fluorescence intensity for ROS at 10 nmol melatonin was significantly greater than controls (P < 0.05). IVF media with 1 mmol melatonin is deleterious for embryo development, and in lower concentrations, it modulated sperm functionality, but had no effects on embryo production.

  6. In vitro culture of Babesia bovis in a bovine serum-free culture medium supplemented with insulin, transferrin, and selenite.

    PubMed

    Rojas Martínez, C; Rodríguez-Vivas, R I; Figueroa Millán, J V; Acosta Viana, K Y; Gutiérrez Ruiz, E J; Álvarez Martínez, J A

    2016-11-01

    Bovine serum is an important factor for the optimal growth of Babesia bovis in vitro. This protozoan can be cultured in M-199 with Earle's salts medium (M-199) supplemented with 40% bovine serum (BS). In the present study, four media were assessed along with the control medium M-199. The effect on the proliferation of B. bovis in vitro was tested when these media were combined with insulin (Ins), transferrin (Trans) and selenite (Sel) in the absence of bovine serum. Treatment with Advanced DMEM/F12 medium (A-DMEM/F12) achieved the highest percentage of parasitized erythrocytes (PPE), reaching a maximum value of 9.59%. A-DMEM/F12 medium supplemented with a mixture of Ins (2000 mg/L), Trans (1100 mg/L), and Sel (1.34 mg/L) allowed for the adaptation and proliferation of B. bovis without bovine serum, showed a constant increase in PPE, and reached a maximum value of 9.7% during seven cycles of in vitro culture. It was concluded that continuous proliferation of B. bovis in vitro could be achieved using A-DMEM/F12 medium supplemented with Ins-Trans-Sel, without bovine serum. After adaptation for proliferation in serum-free medium, the B. bovis strain of parasites could have future use in the study of this economically important protozoan species that affects cattle.

  7. A Hidden Pitfall in the Preparation of Agar Media Undermines Microorganism Cultivability

    PubMed Central

    Tanaka, Tomohiro; Kawasaki, Kosei; Daimon, Serina; Kitagawa, Wataru; Yamamoto, Kyosuke; Tamaki, Hideyuki; Tanaka, Michiko; Nakatsu, Cindy H.

    2014-01-01

    Microbiologists have been using agar growth medium for over 120 years. It revolutionized microbiology in the 1890s when microbiologists were seeking effective methods to isolate microorganisms, which led to the successful cultivation of microorganisms as single clones. But there has been a disparity between total cell counts and cultivable cell counts on plates, often referred to as the “great plate count anomaly,” that has long been a phenomenon that still remains unsolved. Here, we report that a common practice microbiologists have employed to prepare agar medium has a hidden pitfall: when phosphate was autoclaved together with agar to prepare solid growth media (PT medium), total colony counts were remarkably lower than those grown on agar plates in which phosphate and agar were separately autoclaved and mixed right before solidification (PS medium). We used a pure culture of Gemmatimonas aurantiaca T-27T and three representative sources of environmental samples, soil, sediment, and water, as inocula and compared colony counts between PT and PS agar plates. There were higher numbers of CFU on PS medium than on PT medium using G. aurantiaca or any of the environmental samples. Chemical analysis of PT agar plates suggested that hydrogen peroxide was contributing to growth inhibition. Comparison of 454 pyrosequences of the environmental samples to the isolates revealed that taxa grown on PS medium were more reflective of the original community structure than those grown on PT medium. Moreover, more hitherto-uncultivated microbes grew on PS than on PT medium. PMID:25281372

  8. Biological activity of a standardized freeze-dried platelet derivative to be used as cell culture medium supplement.

    PubMed

    Muraglia, Anita; Ottonello, Chiara; Spanò, Raffaele; Dozin, Beatrice; Strada, Paolo; Grandizio, Michele; Cancedda, Ranieri; Mastrogiacomo, Maddalena

    2014-01-01

    Serum of animal origin and in particular fetal bovine serum is the most commonly utilized cell culture medium additive for in vitro cell growth and differentiation. However, several major concerns have been raised by the scientific community regarding the use of animal sera for human cell-based culture applications. Among the possible alternatives to the animal serum, platelet-derived compounds have been proposed since more than 10 years. Nevertheless, the high degree of variability between the different platelet preparations, and the lack of standardized manufacturing and quality control procedures, made difficult to reach a consensus on the applicability of this novel cell culture medium supplement. In this study, we describe the preparation of a standardized platelet-rich plasma (PRP) derivative obtained starting from human-certified buffy coat samples with a defined platelet concentration and following protocols including also freeze-drying, gamma irradiation and biological activity testing prior the product release as cell culture medium additive. Biological activity testing of the different preparations was done by determining the capability of the different PRP preparations to sustain human bone marrow mesenchymal stem cell (MSC) clone formation and proliferation. Taking advantage of a developed MSC in vitro clonogenicity test, we also determined biological activity and stability of the freeze-dried gamma-sterilized PRP preparations after their storage for different times and at different temperatures. The PRP effects on cell proliferation were determined both on primary cell cultures established from different tissues and on a cell line. Results were compared with those obtained in "traditional" parallel control cultures performed in the presence of bovine serum [10% fetal calf serum (FCS)]. Compared to FCS, the PRP addition to the culture medium increased the MSC colony number and average size. In primary cell cultures and in cell line cultures, the PRP

  9. Abolition of Swarming of Proteus by p-Nitrophenyl Glycerin: Application to Blood Agar Media

    PubMed Central

    Williams, Fred D.

    1973-01-01

    Comparative plate counts were made of Staphylococcus aureus and Streptococcus pyogenes growing on blood agar supplemented with individual chemicals to abolish the swarming of Proteus. B-phenylethanol, sodium azide, and p-nitrophenyl glycerin (PNPG) were used as anti-swarm agents. Each anti-swarm agent effectively abolished swarming for 24 h, but azide failed to control swarming for longer periods of incubation. In addition, azide displayed growth inhibition towards the staphylococci and streptococci resulting in no hemolysis and reduced viable cell numbers with the streptococci. Phenylethanol showed reduced viable cell numbers with the streptococci and unreliable hemolytic reactions. At 0.1 to 0.3 mM, PNPG proved to be a superior anti-swarm agent in that it showed no growth inhibition and allowed normal hemolysis, but abolished swarming for extended periods of time. When laboratory strains of Streptococcus pneumoniae, Klebsiella pneumoniae, Pseudomonas aeruginosa. Listeria monocytogenes, and Vibrio cholerae were screened on a blood agar medium containing 0.1 mm PNPG, they displayed similar growth and hemolytic characteristics to the identical medium without PNPG. PMID:4715553

  10. Reduced supplementation frequency increased insulin-like growth factor 1 in beef steers fed medium quality hay and supplemented with a soybean hull and corn gluten feed blend.

    PubMed

    Drewnoski, M E; Huntington, G B; Poore, M H

    2014-06-01

    Reducing supplementation frequency in calf growing programs can reduce labor and equipment operation costs. However, little is understood about the metabolic response of ruminants to large fluctuations in nutrient intake. Eighteen Angus or Angus × Simmental cross steers (287 ± 20 kg and 310 ± 3.6 d of age) were individually fed 1 of 3 dietary treatments using Calan gates. Dietary treatments consisted of ad libitum hay and no supplement (NS), ad libitum hay and 1% BW (as-fed basis) of supplement daily (DS), or ad libitum hay and 2% BW (as-fed basis) of supplement every other day (SA). The supplement was 90% DM and contained (as-fed basis) 47% corn gluten feed, 47% soybean hulls, 2% feed grade limestone, and 4% molasses. Hay intake and ADG was measured over a 52-d period. Steers were then moved to individual tie stalls. Steers were fed at 0800 h and blood samples were collected every hour from 0600 to 1400 h and at 1800, 2200, and 0200 h over a 2-d period. Gains were increased (P < 0.01) by supplementation but did not differ (P = 0.68) due to supplementation frequency. Average daily gain was 0.45, 0.90, and 0.87 kg ·hd(-1)·d(-1) (SEM ± 0.05) for steers NS, DS, and SA, respectively. Across the 2-d supplementation cycle area under the concentration time curve (AUC) for plasma glucose was increased (P < 0.01) by supplementation but did not differ (P = 0.41) due to supplementation frequency. The AUC for plasma insulin was increased by supplementation (P < 0.01) but did not differ (P = 0.67) due to supplementation frequency. Plasma IGF-1 was increased (P = 0.01) by supplementation and was greater (P = 0.04) for steers supplemented SA than DS. Gains of steers supplemented with a soybean hull and corn gluten feed blend on alternate days did not differ from those supplemented daily suggesting the steers were able to efficiently utilize large boluses of nutrients fed every other day. The effect of less frequent supplementation on IGF-1 deserves further examination as

  11. Agrobacterium tumefaciens-mediated transformation of wheat using a superbinary vector and a polyamine-supplemented regeneration medium.

    PubMed

    Khanna, H K; Daggard, G E

    2003-01-01

    Immature embryo-derived calli of spring wheat (Triticum aestivum L.) cv Veery5 were transformed using Agrobacterium tumefaciens strain LBA4404 carrying either binary vector pHK22 or superbinary vector pHK21, the latter carrying an extra set of vir genes--vir B, -C and -G. In both cases, transient beta-glucuronidase ( GUS) expression ranging from 35-63% was observed 3 days after co-cultivation, but 587 calli infected with pHK22/LBA4404 failed to produce a single stably transformed plant, whereas 658 calli infected with pHK21/LBA4404 gave rise to 17 transformants carrying both the GUS and bar genes. Regeneration media supplemented with 0.1 M spermidine improved the recovery of transformants from pHK21/LBA4404-infected calli from 7% to 24.2%, resulting in an increase in the overall transformation frequency from 1.2% to 3.9%. The results suggest that two important factors that could lead to an improvement in transformation frequencies of cereals like wheat are (1) the use of superbinary vectors and (2) modification of the polyamine ratio in the regeneration medium. Stable expression and inheritance of the transgenes was confirmed by both genetic and molecular analyses. T1 progeny showed segregation of the transgenes in a typical Mendelian fashion in most of the plants. Of the transformed plants, 35% showed single-copy insertion of the transgene as shown by both Southern analysis and the segregation ratios.

  12. Comparison of MRSASelect Agar, CHROMagar Methicillin-Resistant Staphylococcus aureus (MRSA) Medium, and Xpert MRSA PCR for Detection of MRSA in Nares: Diagnostic Accuracy for Surveillance Samples with Various Bacterial Densities ▿

    PubMed Central

    Wolk, D. M.; Marx, J. L.; Dominguez, L.; Driscoll, D.; Schifman, R. B.

    2009-01-01

    Rapid laboratory methods provide optimal support for active surveillance efforts to screen for methicillin-resistant Staphylococcus aureus (MRSA). Most laboratories struggle to determine the optimal use of resources, considering options to balance cost, speed, and diagnostic accuracy. To assess the performance of common methods, the first comparison of MRSASelect agar (MS) and CHROMagar MRSA (CA), with and without broth enrichment followed by a 24-h subculture to MS, was performed. Results were compared to those of the Xpert MRSA assay. For direct culture methods, the agreement between MS and CA was 98.8%. At 18 h, direct MS identified 93% of all positive samples from direct culture and 84% of those identified by the Xpert MRSA. For Trypticase soy broth-enriched MS culture, incubated overnight and then subcultured for an additional 24 h, the agreement with Xpert MRSA was 96%. The agreement between direct MS and Xpert MRSA was 100% when semiquantitative culture revealed a bacterial density of 2+ or greater; however, discrepancies between culture and Xpert MRSA arose for MRSA bacterial densities of 1+ or less, indicating low density as a common cause of false-negative culture results. Since 1+ or less was established as the most common MRSA carrier state, broth enrichment or PCR may be critical for the identification of all MRSA carriers who may be reservoirs for transmission. In this active-surveillance convenience sample, the use of broth enrichment followed by subculture to MS offered a low-cost but sensitive method for MRSA screening, with performance similar to that of Xpert MRSA PCR. PMID:19828738

  13. Comparison of MRSASelect Agar, CHROMagar Methicillin-Resistant Staphylococcus aureus (MRSA) Medium, and Xpert MRSA PCR for detection of MRSA in Nares: diagnostic accuracy for surveillance samples with various bacterial densities.

    PubMed

    Wolk, D M; Marx, J L; Dominguez, L; Driscoll, D; Schifman, R B

    2009-12-01

    Rapid laboratory methods provide optimal support for active surveillance efforts to screen for methicillin-resistant Staphylococcus aureus (MRSA). Most laboratories struggle to determine the optimal use of resources, considering options to balance cost, speed, and diagnostic accuracy. To assess the performance of common methods, the first comparison of MRSASelect agar (MS) and CHROMagar MRSA (CA), with and without broth enrichment followed by a 24-h subculture to MS, was performed. Results were compared to those of the Xpert MRSA assay. For direct culture methods, the agreement between MS and CA was 98.8%. At 18 h, direct MS identified 93% of all positive samples from direct culture and 84% of those identified by the Xpert MRSA. For Trypticase soy broth-enriched MS culture, incubated overnight and then subcultured for an additional 24 h, the agreement with Xpert MRSA was 96%. The agreement between direct MS and Xpert MRSA was 100% when semiquantitative culture revealed a bacterial density of 2+ or greater; however, discrepancies between culture and Xpert MRSA arose for MRSA bacterial densities of 1+ or less, indicating low density as a common cause of false-negative culture results. Since 1+ or less was established as the most common MRSA carrier state, broth enrichment or PCR may be critical for the identification of all MRSA carriers who may be reservoirs for transmission. In this active-surveillance convenience sample, the use of broth enrichment followed by subculture to MS offered a low-cost but sensitive method for MRSA screening, with performance similar to that of Xpert MRSA PCR.

  14. Enhanced production of prodigiosin-like pigment from Serratia marcescens SMdeltaR by medium improvement and oil-supplementation strategies.

    PubMed

    Wei, Yu-Hong; Chen, Wei-Chuan

    2005-06-01

    Serratia marcescens SMdeltaR, an SpnR-defective isogenic mutant of S. marcescens SS-1, was used to produce a prodigiosin-like pigment (PLP). Luria-Bertani (LB) broth, frequently used for prodigiosin biosynthesis with S. marcescens strains, was modified by increasing the concentrations of tryptone and yeast extract while completely removing NaCl from the medium. The resulting modified LB (MLB) medium achieved an almost 3.0-fold increase in PLP yield (152 mg l(-1)) when compared with the original LB broth. The addition of vegetable oils (2-6% [v/v]) to the fermentation broth markedly enhanced PLP production. PLP yields of 525, 579, and 790 mg l(-1) were obtained when the MLB medium was supplemented with 4% soybean oil, 4% olive oil and 6% sunflower oil, respectively. PLP production was found to be positively correlated with extracellular surface emulsification activity, suggesting a link between the PLP production and the presence of biosurfactant. This work shows that the optimal medium for PLP yield was sunflower oil (6%)-supplemented MLB medium, which resulted in an approximately 14-fold higher PLP yield than that in LB broth. Mass spectrometry and NMR analysis indicated that the PLP product is a prodigiosin derivative, called undecylprodigiosin.

  15. A brief dataset on the model-based evaluation of the growth performance of Bacillus coagulans and l-lactic acid production in a lignin-supplemented medium.

    PubMed

    Glaser, Robert; Venus, Joachim

    2017-04-01

    The data presented in this article are related to the research article entitled "Model-based characterization of growth performance and l-lactic acid production with high optical purity by thermophilic Bacillus coagulans in a lignin-supplemented mixed substrate medium (R. Glaser and J. Venus, 2016) [1]". This data survey provides the information on characterization of three Bacillus coagulans strains. Information on cofermentation of lignocellulose-related sugars in lignin-containing media is given. Basic characterization data are supported by optical-density high-throughput screening and parameter adjustment to logistic growth models. Lab scale fermentation procedures are examined by model adjustment of a Monod kinetics-based growth model. Lignin consumption is analyzed using the data on decolorization of a lignin-supplemented minimal medium.

  16. Corneal keratocyte transition to mesenchymal stem cell phenotype and reversal using serum-free medium supplemented with FGF-2, TGF-ß3 and retinoic acid.

    PubMed

    Sidney, Laura E; Hopkinson, Andrew

    2016-09-29

    Keratocytes of the corneal limbal stroma can derive populations of mesenchymal stem cells (MSC) when expanded in vitro. However, once a corneal MSC (cMSC) phenotype is achieved, regaining the keratocyte phenotype can be challenging, and there is no standardised differentiation medium. Here, we investigated the transition of keratocytes to cMSC and compared different supplements in their ability to return cMSC to a keratocyte phenotype. Immunofluorescence and RT-qPCR demonstrated in vivo keratocyte expression of ALDH3A1, CD34 and keratocan, but not any of the typical MSC markers (CD73, CD90, CD105). As the keratocytes were expanded in vitro, the phenotypic profile reversed and the cells expressed MSC markers but not keratocyte markers. Differentiating the cMSC back to a keratocyte phenotype using non-supplemented, serum-free medium restored keratocyte markers but did not maintain cell viability or support corneal extracellular matrix (ECM) production. Supplementing the differentiation medium with combinations of fibroblast growth factor-2 (FGF-2), transforming growth factor-β3 (TGF-β3) and retinoic acid (RA) maintained viability, restored expression of CD34, ALDH3A1 and keratocan, and facilitated production of abundant ECM as shown by immunofluorescent staining for collagen-I and lumican, alongside quantitative assays for collagen and glycosaminoglycan production. However, no differentiation medium was able to downregulate the expression of MSC markers in the 21-day culture period. This study shows that the keratocyte to MSC transition can be partially reversed using serum-free media and supplementation with RA, FGF-2 and TGF-β3 can enhance this effect. This is relevant for development of corneal regenerative strategies that require the production of a keratocyte phenotype.

  17. Effect of sericin supplementation in maturation medium on cumulus cell expansion, oocyte nuclear maturation, and subsequent embryo development in Sanjabi ewes during the breeding season.

    PubMed

    Aghaz, F; Hajarian, H; Shabankareh, H Karami; Abdolmohammadi, A

    2015-12-01

    The purpose of this study was to evaluate the effect of sericin with different concentrations (0% [control], 0.1%, 0.5%, 1.0%, and 2.5%) added to the IVM medium on cumulus cell expansion, oocyte nuclear maturation, and subsequent embryo development in Sanjabi ewes during the breeding season. The resumption of meiosis was assessed by the frequency of germinal vesicle breakdown and the first polar body extrusion. After IVF with fresh ram semen, presumptive zygotes were cultured 8 days in potassium simplex optimization medium supplemented by amino acids, and the percentages developing to the two-cell and blastocyst stages were measured as the indicators of early embryonic developmental competence. More cumulus-oocyte complexes matured with 0.5% sericin underwent germinal vesicle breakdown and reached metaphase II stage compared with the control cumulus-oocyte complexes matured without sericin (P ≤ 0.05). The present findings indicated that supplementation with 0.5% sericin during the maturation culture may improve the nuclear maturation and the cumulus cell expansion. Furthermore, the percentage of blastocysts obtained from 0.5% and 0.1% sericin (37.8 ± 1.76% and 34.8 ± 1.09%, respectively) was higher (P ≤ 0.05) than that of the control medium (29.60 ± 1.67%). However, addition of 1% and 2.5% of sericin to the IVM medium oocytes had a negative effect on nuclear maturation and cumulus cell expansion. Furthermore, the percentage of cleavage and blastocyst rate was significantly lower in the 1% and 2.5% sericin groups than in the control group. These findings showed that supplementation of IVM medium with 0.5% sericin may improve the meiotic competence of oocytes and early embryonic development in Sanjabi ewes during the breeding season.

  18. A simple and effective method for the removal of trace metal cations from a mammalian culture medium supplemented with 10% fetal calf serum.

    PubMed

    Rayner, M H; Suzuki, K T

    1995-07-01

    Direct batch addition of sterile Chelex ion-exchange resin to Dubecco's modified Eagle's medium supplemented with 10% fetal calf serum with gentle stirring removed a very wide variety of trace metal ions from the medium to varying extents dependent upon Chelex content (between 0.01 and 4% w/v), exposure time (between 5 min and 10 days) and temperature (4, 25 and 37 degrees C). Prolonged treatment (10 days) with 4% w/v Chelex at 4 degrees C reduced the concentration of zinc, strontium, aluminum, copper, manganese, nickel and chromium from 100 to 2.7, 12.1, 7.7, 22.6, 13.0, 14.7 and 53.3% of their original concentrations, respectively. Re-supplementation of the metal depleted medium with a defined cocktail of metals restored the growth potential of the medium which was then capable of supporting growth over at least three subcultures without a decrease in fibroblast cell yield, demonstrating its suitability in cell culture studies on trace metal ions.

  19. Highly efficient synthesis of exopolysaccharides by Lactobacillus curvatus DPPMA10 during growth in hydrolyzed wheat flour agar.

    PubMed

    Minervini, F; De Angelis, M; Surico, R F; Di Cagno, R; Gänzle, M; Gobbetti, M

    2010-06-30

    The aim of this study was to optimize the production of exopolysaccharides (EPS) by sourdough Lactobacillus curvatus DPPMA10 for industrial application. The effects of pH, temperature, planktonic or attached cells and of some food matrices as substrates were studied. Wheat flour hydrolysate (WFH), reconstituted skimmed milk (RSM) and whey milk were supplemented with fresh yeast extract, mineral salts, and/or molasses. Non-controlled pH, starting from 5.6 to 3.5, was the optimal condition for L. curvatus DPPMA10. Temperature of 30 degrees C was also found to be optimal. Solid surfaces (agar culture media) stimulated attached bacteria to synthesize EPS (> or = of two-fold, P<0.05) with respect to planktonic cells (broth media). The highest production of EPS (ca. 46-50 g/kg of wet medium) was found during growth as attached cells in WFH agar supplemented with glucose, sucrose or molasses, mineral salts and fresh yeast extract at 30 degrees C for 48 h. As shown by high-performance liquid chromatography analysis, glucose was the only hydrolysis end-product for EPS synthesized during 48 h of incubation. The EPS synthesized by L. curvatus DPPMA10 improved the quality of bread and was utilized as carbon course by intestinal strains of lactobacilli and bifidobacteria. The synthesis of EPS by L. curvatus DPPMA10 under the conditions of this study may open new perspectives for their industrial applications.

  20. Effect of protein supplementation and presence of an antioxidant on the development of bovine zygotes in synthetic oviduct fluid medium under high or low oxygen tension.

    PubMed

    Lonergan, P; O'Kearney-Flynn, M; Boland, M P

    1999-06-01

    The aim of this study was to investigate the effect of protein supplementation of culture medium and the presence of a putative antioxidant on bovine zygote development under 5% (low) and 20% (high) O2. In Experiment 1, presumptive zygotes (n=992) were cultured in synthetic oviduct fluid (SOF) alone or supplemented with 3 mg/mL PVP, 3 mg/mL BSA (SOFB), and/or 10% FCS (SOFBF) in 5% CO2, 5% O2, 90% N2. In Experiment 2, zygotes (n=1916) were cultured in SOF, SOFB or SOFBF with or without taurine under high and low O2. In Experiment 1, presence of BSA or BSA plus FCS significantly increased the speed of development compared to SOF or SOF+PVP. Blastocyst quality was also improved, as evidenced by increased hatching rate and cell numbers. In Experiments 2, taurine had no effect on development irrespective of oxygen concentration or protein supplementation. In conclusion, the presence of protein in the culture medium and culture under reduced O2 significantly improved embryo development. Taurine had no effect on development.

  1. Identification of Salmonella spp. with Rambach agar in conjunction with the 4-methylumbelliferyl caprylate (MUCAP) fluorescence test.

    PubMed

    Abdalla, S; Vila, J; Jimenez de Anta, M T

    1994-03-01

    The utility of Rambach agar to identify Salmonella spp. was examined relative to its usefulness in clinical microbiology. Forty-four of 54 (82%) salmonella organisms isolated from faecal cultures and 66 of 82 (84%) salmonella stock cultures produced bright red colour colonies after 24 h incubation at 37 degrees C, whereas 48 of 54 (89%) salmonellae isolated from faecal cultures, and 74 of 82 (90%) salmonella stock cultures, yielded the bright red colour when the incubation time was extended to 48 h. Apart from Salmonella typhi and Salmonella paratyphi A the sensitivity of Rambach agar to detect salmonella strains belonging to five serogroups was 83% and 92% after 24 and 48 h of incubation, respectively. In contrast, other members of the family Enterobacteriaceae tested failed to give the bright red colour, except for one strain of Pseudomonas aeruginosa and another of Acinetobacter baumannii. The non-salmonella strains either gave a different colour--blue, green or orange--or were colourless. To supplement the use of Rambach agar in the detection of Salm. typhi and Salm. paratyphi A and other late or negative acid-producing salmonella species on this medium, the 4-methylumbelliferyl caprylate fluorescence (MUCAP) test was carried out, and this showed positive results with all the salmonella strains tested. These results suggest that while Rambach agar can not pre-identify Salm. typhi and Salm. paratyphi A, the use of a simple and rapid (MUCAP) test in combination would make it very useful to identify all Salmonella spp. after 24 h incubation.

  2. Tooth Tissue Engineering: The Importance of Blood Products as a Supplement in Tissue Culture Medium for Human Pulp Dental Stem Cells.

    PubMed

    Pisciolaro, Ricardo Luiz; Duailibi, Monica Talarico; Novo, Neil Ferreira; Juliano, Yara; Pallos, Debora; Yelick, Pamela Crotty; Vacanti, Joseph Phillip; Ferreira, Lydia Masako; Duailibi, Silvio Eduardo

    2015-11-01

    One of the goals in using cells for tissue engineering (TE) and cell therapy consists of optimizing the medium for cell culture. The present study compares three different blood product supplements for improved cell proliferation and protection against DNA damage in cultured human dental pulp stem cells for tooth TE applications. Human cells from dental pulp were first characterized as adult stem cells (ectomesenchymal mixed origin) by flow cytometry. Next, four different cell culture conditions were tested: I, supplement-free; II, supplemented with fetal bovine serum; III, allogeneic human serum; and IV, autologous human serum. Cultured cells were then characterized for cell proliferation, mineralized nodule formation, and colony-forming units (CFU) capability. After 28 days in culture, the comet assay was performed to assess possible damage in cellular DNA. Our results revealed that Protocol IV achieved higher cell proliferation than Protocol I (p = 0.0112). Protocols II and III resulted in higher cell proliferation than Protocol I, but no statistical differences were found relative to Protocol IV. The comet assay revealed less cell damage in cells cultured using Protocol IV as compared to Protocols II and III. The damage percentage observed on Protocol II was significantly higher than all other protocols. CFUs capability was highest using Protocol IV (p = 0.0018) and III, respectively, and the highest degree of mineralization was observed using Protocol IV as compared to Protocols II and III. Protocol IV resulted in significantly improved cell proliferation, and no cell damage was observed. These results demonstrate that human blood product supplements can be used as feasible supplements for culturing adult human dental stem cells.

  3. A novel chemical-defined medium with bFGF and N2B27 supplements supports undifferentiated growth in human embryonic stem cells

    SciTech Connect

    Liu Yanxia; Song Zhihua; Zhao Yang; Qin Han; Cai Jun; Zhang Hong; Yu Tianxin; Jiang Siming; Wang Guangwen; Ding Mingxiao; Deng Hongkui . E-mail: hongkui_deng@pku.edu.cn

    2006-07-21

    Traditionally, undifferentiated human embryonic stem cells (hESCs) are maintained on mouse embryonic fibroblast (MEF) cells or on matrigel with an MEF-conditioned medium (CM), which hampers the clinical applications of hESCs due to the contamination by animal pathogens. Here we report a novel chemical-defined medium using DMEM/F12 supplemented with N2, B27, and basic fibroblast growth factor (bFGF) [termed NBF]. This medium can support prolonged self-renewal of hESCs. hESCs cultured in NBF maintain an undifferentiated state and normal karyotype, are able to form embryoid bodies in vitro, and differentiate into three germ layers and extraembryonic cells. Furthermore, we find that hESCs cultured in NBF possess a low apoptosis rate and a high proliferation rate compared with those cultured in MEF-CM. Our findings provide a novel, simplified chemical-defined culture medium suitable for further therapeutic applications and developmental studies of hESCs.

  4. Evaluation of a new dipslide with a selective medium for the rapid detection of beta-glucuronidase-positive Escherichia coli.

    PubMed

    Larinkari, U; Rautio, M

    1995-07-01

    A selective medium was incorporated into a new three-media dipslide (Uricult Trio, Orion Diagnostica) to allow rapid identification of Escherichia coli. The medium is supplemented with a recently described chromogenic substrate, hydroxyquinoline-beta-D-glucuronide, for beta-glucuronidase enzyme. The performance of the medium was compared to that of three other beta-glucuronidase detection methods in tests of 602 routine urine samples. Of 324 Escherichia coli strains isolated, 92% grew brown colonies on dipslide, thus being beta-glucuronidase positive. The proportion of beta-glucuronidase-positive Escherichia coli detected by the three methods was 93% for BGA II agar plates (Tammer-Tutka), 91% for PGUA tablets (Rosco) and 84% for Fluorocult Brolacin agar plates (Merck). No false-positive reactions were seen in the case of 209 significant isolates of species other than Escherichia coli grown on the selective medium.

  5. Strategies for reducing supplemental medium cost in bioethanol production from waste house wood hydrolysate by ethanologenic Escherichia coli: inoculum size increase and coculture with Saccharomyces cerevisiae.

    PubMed

    Okuda, Naoyuki; Ninomiya, Kazuaki; Katakura, Yoshio; Shioya, Suteaki

    2008-02-01

    In this paper, we report a simultaneous realization of both efficient ethanol production and saving medium nutrient (corn steep liquor [CSL]) during bioethanol fermentation of overliming-treated hydrolysate of waste house wood (WHW) using ethanologenic Escherichia coli KO11. In cultivation using WHW hydrolysate supplemented with 4% (v/v) CSL and 0.2 g-dry cell weight (DCW)/l E. coli KO11 cells, the overall ethanol yield reached 84% of the theoretical value at 61 h. When we conducted the cultivation with 1% CSL to reduce the supplemental medium cost, the overall ethanol yield remained in the range of 66-72% even at 90 h. We proposed two alternative methods for increasing the overall yield even with 1% CSL. The first method involved increasing the inoculum size of E. coli KO11 up to 0.8 g-DCW/l, where 83% of the overall yield was attained at 60 h of cultivation. The second method involved the coculture of 0.2 g-DCW/l E. coli KO11 together with 0.02 g-DCW/l of Saccharomyces cerevisiae TJ1, and the overall yield reached 81% at 47 h of cultivation.

  6. Comparison of agar-based media for primary isolation of glycopeptide-resistant enterococci.

    PubMed

    Chadwick, P. R.; Brown, D. F. J.; Wilcox, M. H.; Collyns, T. A.; Walpole, E.; Dillon, J.; Smith, R.; Gopal Rao, G.; Oppenheim, B. A.

    1997-01-01

    OBJECTIVE: To compare four vancomycin-containing agar media for the isolation of glycopeptide-resistant enterococci (GRE) from clinical fecal specimens: kanamycin---aesculin---azide (KAA) agar; bile---aesculin---polymixin (BAP) agar; aztreonam---amphotericin blood (CBAA) agar; and neomycin blood (CBN) agar. METHODS: Fecal specimens from 125 patients were inoculated onto each medium. Media were examined for enterococci after incubation for up to 48 h. Enterococci were identified to species level, and glycopeptide phenotypes were determined by measuring minimum inhibitory concentrations of vancomycin and teicoplanin. RESULTS: GRE were isolated from 44/125 samples. Enterococcus faecalis and Enterococcus faecium isolates, expressing glycopeptide resistance of the VanA or VanB phenotypes, were recovered from 27/33 (82%) specimens on BAP medium, 26/33 (79%) on KAA medium, and 21/33 (64%) on CBN and CBAA media. Enterococcus gallinarum and Enterococcus casseliflavus isolates expressing low-level glycopeptide resistance (VanC phenotype) were recovered from 14/15 (93%) specimens on CBAA medium, 7/15 (47%) on KAA and CBN media, and 6/15 (40%) on BAP medium. CONCLUSIONS: The media tested in this study, with the exception of CBN medium, detected at least 75% of patients colonized by GRE. Further development of BAP, CBAA and KAA media is warranted to improve growth and selectivity.

  7. Application of a modified culture medium for the simultaneous counting of molds and yeasts and detection of aflatoxigenic strains of Aspergillus flavus and Aspergillus parasiticus.

    PubMed

    Jaimez, J; Fente, C A; Franco, C M; Cepeda, A; Vázquez, B I

    2003-02-01

    Molds and yeasts from 91 samples of feed and raw materials used in feed formulation were enumerated on a new culture medium to which a beta cyclodextrin (beta-W7M 1.8-cyclodextrin) had been added. This medium was compared with other media normally used in laboratories for the routine analysis of fungi, such as Sabouraud agar, malt agar supplemented with 2% dextrose, and potato dextrose agar. When a t test for paired data (0.05 significance level, 95% confidence interval) was applied, no statistically significant differences between the results obtained with the new culture medium and those obtained with the other media used to enumerate molds and yeasts were found. For the evaluation of contamination due to aflatoxin for all of the samples, Sabouraud agar and yeast extract agar, both supplemented with 0.3% beta-W7M 1.8-cyclodextrin, and APA (aflatoxin-producing ability) medium were used. Aflatoxin was detected in 21% of the feed samples and in 23% of the raw-material samples analyzed, with maximal amounts of 2.8 and 6.0 microg of aflatoxin B1 per kg, respectively, being detected. In any case, the aflatoxin contents found exceeded the legally stipulated limits. The t test for paired data (0.05 significance level, 95% confidence interval) did not show statistically significant differences between the results obtained with the different culture media used for the detection of aflatoxins. The advantage of the new medium developed (Sabouraud agar with 0.3% beta-W7M 1.8-cyclodextrin) is that it allows simultaneous fungal enumeration and determination (under UV light) of the presence of aflatoxin-producing strains without prior isolation and culture procedures involving expensive and/or complex specific media and thus saves work, time, and money.

  8. Effect of supplementing coconut or krabok oil, rich in medium-chain fatty acids on ruminal fermentation, protozoa and archaeal population of bulls.

    PubMed

    Panyakaew, P; Boon, N; Goel, G; Yuangklang, C; Schonewille, J Th; Hendriks, W H; Fievez, V

    2013-12-01

    Medium-chain fatty acids (MCFA), for example, capric acid (C10:0), myristic (C14:0) and lauric (C12:0) acid, have been suggested to decrease rumen archaeal abundance and protozoal numbers. This study aimed to compare the effect of MCFA, either supplied through krabok (KO) or coconut (CO) oil, on rumen fermentation, protozoal counts and archaeal abundance, as well as their diversity and functional organization. KO contains similar amounts of C12:0 as CO (420 and 458 g/kg FA, respectively), but has a higher proportion of C14:0 (464 v. 205 g/kg FA, respectively). Treatments contained 35 g supplemental fat per kg DM: a control diet with tallow (T); a diet with supplemental CO; and a diet with supplemental KO. A 4th treatment consisted of a diet with similar amounts of MCFA (i.e. C10:0+C12:0+C14:0) from CO and KO. To ensure isolipidic diets, extra tallow was supplied in the latter treatment (KO+T). Eight fistulated bulls (two bulls per treatment), fed a total mixed ration predominantly based on cassava chips, rice straw, tomato pomace, rice bran and soybean meal (1.5% of BW), were used. Both KO and CO increased the rumen volatile fatty acids, in particular propionate and decreased acetate proportions. Protozoal numbers were reduced through the supplementation of an MCFA source (CO, KO and KO+T), with the strongest reduction by KO. Quantitative real-time polymerase chain reaction assays based on archaeal primers showed a decrease in abundance of Archaea when supplementing with KO and KO+T compared with T and CO. The denaturing gradient gel electrophoresis profiles of the rumen archaeal population did not result in a grouping of treatments. Richness indices were calculated from the number of DGGE bands, whereas community organization was assessed from the Pareto-Lorenz evenness curves on the basis of DGGE band intensities. KO supplementation (KO and KO+T treatments) increased richness and evenness within the archaeal community. Further research including methane

  9. The physicochemical property characterization of agar acetate.

    PubMed

    Xia, Kai; Liu, Xin; Zhao, Jingkun; Zhang, Xiaodong

    2014-09-22

    A series of agar acetates with different degree of substitution (DS) were prepared, and their properties were determined and analyzed. The results showed that the gelling temperature, the gel melting temperature, the gel strength, the gel hardness, the gel fracturability, the gel springiness and the solution apparent viscosity of agar acetates all decreased except that their gel cohesiveness increased with the increase of DS. The variation process of agar molecules in solution from coil to helix could be also observed by measuring solution optical rotation in a lower concentration at which even the solution could not form a gel. The gel skeleton structures of agar acetates were of porous network structures, and the pores became smaller and denser with the increase of DS. After acetylation, the water holding capacity of the agar was improved, but its thermal stability was lowered.

  10. Phenotypic identification of Candida albicans by growth on chocolate agar.

    PubMed

    Sheth, Chirag C; Johnson, Elizabeth; Baker, Mark E; Haynes, Ken; Mühlschlegel, Fritz A

    2005-12-01

    In this study, we describe a simple method for the identification of Candida albicans in clinical samples. A total of 383 clinical isolates of Candida species were streaked onto chocolate agar and incubated for 48 h at 37 degrees C in the presence of an atmosphere of 6% CO2. All 208 of the C. albicans isolates tested, developed an easy to identify filamentous colony morphology. Of 175 other Candida species tested, 172 (98.3%) were distinguishable from C. albicans by their smooth colony morphology. Three isolates (1.7%) exhibited weak filamentation after prolonged incubation. Although not a routine medium in medical mycology a significant advantage of using chocolate agar lies in its use in clinical bacteriology laboratories for the isolation of fastidious bacteria. Implementation of the proposed method is applicable across a range of specimen types, thus allowing the direct identification of C. albicans in clinical samples. This simple method may allow a quicker entry into directed treatment.

  11. Xanthan gum: an economical partial substitute for agar in microbial culture media.

    PubMed

    Babbar, Shashi B; Jain, Ruchi

    2006-04-01

    Xanthan gum, microbial desiccation-resistant polysaccharide prepared commercially by aerobic submerged fermentation from Xanthomonas campestris, has been successfully used alone and in combination with agar for microbial culture media. As illustrative examples, eight bacteria and eight fungi were grown on media solidified with either agar (A, 1.5%), xanthan gum (X, 1%), or combinations of both (0.9% X + 0.1% A, 0.8% X + 0.2% A, 0.7% X + 0.3% A, 0.6% X + 0.4% A). All fungi and bacteria exhibited normal growth and differentiation in all these treatments. Rather, growth of most of the fungi was better on xanthan (alone) and xanthan + agar media than agar medium. As the media gelled with xanthan gum alone flow, it was not possible to incubate Petri plates in inverted position. Moreover, because of the softness, streaking of bacteria was difficult on such media. However, these problems could be overcome by partially replacing xanthan gum with 0.3% agar. Bacterial enumeration studies carried out for Serratia sp. and Pseudomonas sp. by serial dilution and pour-plate method on agar (1.5%), 0.7%/0.6% X + 0.3%/0.4% A yielded similar counts. Selective media, succinate medium for Pseudomonas sp., and MacConkey broth medium for Escherichia coli gelled with 0.7%/0.6% X + 0.3%/0.4% A did not support growth of other bacteria when inoculated along with the above-mentioned bacteria. Likewise, differential medium, CRMA (Congo red mannitol agar) gelled with xanthan-agar combination could differentiate between Agrobacterium tumefaciens and Rhizobium sp.

  12. Isolation of Asticcacaulis sp. SA7, a novel agar-degrading alphaproteobacterium.

    PubMed

    Hosoda, Akifumi; Sakai, Masao

    2006-03-01

    An agar-degrading bacterium, strain SA7, was isolated from plant roots cultivated in soil. Analysis of the 16S rDNA sequence showed that strain SA7 is affiliated with the genus Asticcacaulis. Strain SA7 produced extracellular agarase, and grew utilizing agar in the culture medium as sole carbon source. Zymogram analysis showed that strain SA7 extracellularly secreted single agarase protein (about 70 kDa).

  13. Growth and phenotypic characterization of Legionella species on semisolid media made with washed agar.

    PubMed Central

    Rogers, J E; Jones, G W; Engleberg, N C

    1993-01-01

    Legionella pneumophila (and 28 Legionella species) grew efficiently on charcoal-free, buffered yeast extract medium made with washed agar and without apparent loss of infectivity for U937 cells. Because charcoal-free, buffered yeast extract is transparent, it is a suitable base for indicator media and pigment detection. In standard media, charcoal apparently prevents agar contaminants from inhibiting Legionella growth. Images PMID:8417021

  14. Viability of rat spermatogenic cells in vitro is facilitated by their coculture with Sertoli cells in serum-free hormone-supplemented medium.

    PubMed Central

    Tres, L L; Kierszenbaum, A L

    1983-01-01

    Spermatogenic cells from 20- to 35-day-old rats were grown in vitro in the presence of Sertoli cells maintained in serum-free hormone/growth factor-supplemented medium and alternating high/low concentrations of follicle-stimulating hormone in the medium. In cell reaggregation experiments, spermatogenic cells reassociate with Sertoli cells but not with peritubular cells or cell-free substrate. Autoradiographic experiments using [3H]thymidine as a labeled precursor for DNA synthesis show that spermatogonia and preleptotene spermatocytes, connected by cytoplasmic bridges, have a synchronous S phase. [3H]Thymidine-labeled preleptotene spermatocytes progress until later stages of meiotic prophase. Time-lapse cinematographic studies of Sertoli/spermatogenic cell cocultures show three major movement patterns. While Sertoli cell cytoplasmic processes between adjacent cells display tensional forces, spermatogonia are engaged in oscillatory cell movements different from the nuclear rotation observed in meiotic prophase spermatocytes. Results of this study show that the proliferation of premeiotic cells and the differentiation of meiotic prophase cells do occur in vitro in association with Sertoli cells maintained in a medium that allows differentiated cell functions. Images PMID:6407012

  15. A novel agar formulation for isolation and direct enumeration of Vibrio vulnificus from oyster tissue.

    PubMed

    Griffitt, Kimberly J; Grimes, D Jay

    2013-08-01

    A new selective and differential medium, Vibrio vulnificus X-Gal (VVX), was developed for direct enumeration of V. vulnificus (Vv) from oyster samples. This agar utilizes cellobiose and lactose as carbon sources, and the antibiotics colistin and polymyxin B as selective agents. Hydrolysis of 5-bromo-4-chloro-3-indolyl- beta-d-galactopyranoside (x-gal), used in the agar as a lactose analog, produces an insoluble blue dye that makes lactose positive colonies easily distinguishable from any non-lactose fermenting bacteria. Various bacterial species were spot plated onto thiosulfate-citrate-bile salts-sucrose agar (TCBS), and CHROMagar Vibrio, two vibrio-specific selective agars, non-selective agar, and VVX to compare selectivity of VVX to other widely used media. A V. vulnificus pure culture was serially diluted on VVX and non-selective agar to determine the VVX percent recovery. Water and oyster samples were spread plated on VVX agar and allowed to incubate for 16-18 h at 33 °C. Blue and white colonies from VVX agar were picked and screened by end point PCR for the Vv hemolysin vvhA. VVX agar showed a significant improvement over TCBS and CHROMagar at preventing non-target growth. There was an 87.5% recovery compared to non-selective plating and a 98% positivity rate of blue colonies picked from oyster tissue plating. The findings suggest that this new agar is a fast, distinctive, and accurate method for enumeration of V. vulnificus from the environment.

  16. Chromium (VI) biosorption and removal of chemical oxygen demand by Spirulina platensis from wastewater-supplemented culture medium.

    PubMed

    Magro, Clinei D; Deon, Maitê C; De Rossi, Andreia; Reinehr, Christian O; Hemkemeier, Marcelo; Colla, Luciane M

    2012-01-01

    The inappropriate discharge of wastewater containing high concentrations of toxic metals is a serious threat to the environment. Given that the microalga Spirulina platensis has demonstrated a capacity for chromium VI (Cr (VI) biosorption, we assessed the ideal concentration of chromium-containing wastewater required for maximum removal of Cr (VI) and chemical oxygen demand (COD) from the environment by using this microalga. The Paracas and Leb-52 strains of S. platensis, with initial wastewater concentrations of 0%, 12.5%, 25%, and 50%, were cultured in Zarrouk medium diluted to 50% under controlled air, temperature, and lighting conditions. The cultures were maintained for 28 days, and pH, biomass growth, COD, and Cr (VI) were assessed. The wastewater concentration influenced microalgal growth, especially at high concentrations. Removal of 82.19% COD and 60.92% Cr (VI) was obtained, but the COD removal was greater than the Cr (VI) removal in both strains of S. platensis.

  17. High rate of N2 fixation by East Siberian cryophilic soil bacteria as determined by measuring acetylene reduction in nitrogen-poor medium solidified with gellan gum.

    PubMed

    Hara, Shintaro; Hashidoko, Yasuyuki; Desyatkin, Roman V; Hatano, Ryusuke; Tahara, Satoshi

    2009-05-01

    For evaluating N(2) fixation of diazotrophic bacteria, nitrogen-poor liquid media supplemented with at least 0.5% sugar and 0.2% agar are widely used for acetylene reduction assays. In such a soft gel medium, however, many N(2)-fixing soil bacteria generally show only trace acetylene reduction activity. Here, we report that use of a N(2) fixation medium solidified with gellan gum instead of agar promoted growth of some gellan-preferring soil bacteria. In a soft gel medium solidified with 0.3% gellan gum under appropriate culture conditions, bacterial microbiota from boreal forest bed soils and some free-living N(2)-fixing soil bacteria isolated from the microbiota exhibited 10- to 200-fold-higher acetylene reduction than those cultured in 0.2% agar medium. To determine the N(2) fixation-activating mechanism of gellan gum medium, qualitative differences in the colony-forming bacterial components from tested soil microbiota were investigated in plate cultures solidified with either agar or gellan gum for use with modified Winogradsky's medium. On 1.5% agar plates, apparently cryophilic bacterial microbiota showed strictly distinguishable microbiota according to the depth of soil in samples from an eastern Siberian Taiga forest bed. Some pure cultures of proteobacteria, such as Pseudomonas fluorescens and Burkholderia xenovorans, showed remarkable acetylene reduction. On plates solidified with 1.0% gellan gum, some soil bacteria, including Luteibacter sp., Janthinobacterium sp., Paenibacillus sp., and Arthrobacter sp., uniquely grew that had not grown in the presence of the same inoculants on agar plates. In contrast, Pseudomonas spp. and Burkholderia spp. were apparent only as minor colonies on the gellan gum plates. Moreover, only gellan gum plates allowed some bacteria, particularly those isolated from the shallow organic soil layer, to actively swarm. In consequence, gellan gum is a useful gel matrix to bring out growth potential capabilities of many soil

  18. Effect of supplementation of different growth factors in embryo culture medium with a small number of bovine embryos on in vitro embryo development and quality.

    PubMed

    Ahumada, C J; Salvador, I; Cebrian-Serrano, A; Lopera, R; Silvestre, M A

    2013-03-01

    When embryos are cultured individually or in small groups, blastocyst yield efficiency and quality are usually reduced. The aim of this work was to investigate the effect of supplementation of the embryo culture medium (CM) with several growth factors (GFs) on embryo development and apoptosis rate when a reduced number of embryos were in vitro cultured. Two experimental studies (ES) were carried out. In ES 1, five treatments were tested to study the effect of GF on embryo development: Control (∼30 to 50 embryos cultured in 500 μl of CM); Control 5 (Five embryos cultured in 50 μl microdrops of CM), without addition of GF in either of the two control groups; epidermal GF (EGF); IGF-I; and transforming GF-α (TGF-α) (Five embryos were cultured in 50 μl microdrops of CM with 10 ng/ml EGF, 10 ng/ml IGF-I or 10 ng/ml TGF-α, respectively). In ES 2, following the results obtained in ES 1, four different treatments were tested to study their effect on embryo development and quality (number of cells per blastocyst and apoptotic rate): Control; Control 5; EGF, all three similar to ES 1; EGF + IGF-I group (five embryos cultured in 50 μl microdrops of CM with 10 ng/ml EGF and 10 ng/ml IGF-I). In both ESs, it was observed that a higher proportion of embryos cultured in larger groups achieved blastocyst stage than embryos cultured in reduced groups (22.6% v. 14.0%, 12.6% and 5.3% for Control v. Control 5, IGF-I, TGF-α groups in ES 1, and 24.9% v. 17.1% and 19.0% for Control v. Control 5 and EGF in ES 2, respectively; P < 0.05), with the exception of embryos cultured in medium supplemented with EGF (18.5%) or with EGF + IGF-I (23.5%), in ES 1 and ES 2, respectively. With regard to blastocyst quality, embryos cultured in reduced groups and supplemented with EGF, alone or combined with IGF-I, presented lower apoptosis rates than embryos cultured in reduced groups without GF supplementation (11.6% and 10.5% v. 21.9% for EGF, EGF + IGF-I and Control 5 groups, respectively; P

  19. Caprine ovarian follicle requirements differ between preantral and early antral stages after IVC in medium supplemented with GH and VEGF alone or in combination.

    PubMed

    Cadenas, J; Leiva-Revilla, J; Vieira, L A; Apolloni, L B; Aguiar, F L N; Alves, B G; Lobo, C H; Rodrigues, A P R; Apgar, G A; Smitz, J; Figueiredo, J R; Maside, C

    2017-01-01

    The aim of the present study was to evaluate the effect of growth hormone (GH) and vascular endothelial growth factor (VEGF) added alone, sequentially or in combination, in the presence of insulin at physiological concentration (10 ng/mL) on the IVC of two different follicular categories: preantral (experiment 1; Exp.1) and early antral (experiment 2; Exp.2). Isolated follicles were individually cultured for 24 (Exp.1) and 18 days (Exp.2) in the following treatments: αMEM(+) (Control), or Control medium supplemented with 50 ng/mL GH (GH), 100 ng/mL VEGF (VEGF), the combination of both (GH + VEGF), GH during the first 12 days and VEGF from Day 12 until the end of the culture (GH/VEGF) and vice versa (VEGF/GH). At the end of the culture, cumulus-oocyte complexes from in vitro-grown follicles were recovered and subjected to IVM. The following end points were evaluated: Follicle morphology, growth rates and antrum formation, production of estradiol, progesterone and testosterone, oocyte viability and meiotic stage, as well as relative expression of LHR, Amh, HAS2, PTGS2, CYP17, CYP19A1, and 3βHSD. A considerable amount of viable fully grown oocytes were recovered after the IVC of early antral follicles in all treatments. Nevertheless, the GH treatment presented the highest percentage of fully grown oocytes (60%), mean oocyte diameter (117.74 ± 2.61 μm), and meiotic resumption (50%). Furthermore, GH treatment produced higher (P < 0.05) rates of metaphase II oocytes than all the other treatments, and similar LHR, Amh, and PTGS2 transcript levels to in vivo. Contrary to early antral follicles, preantral follicles were not affected by medium supplementation. In conclusion, the addition of GH to a culture medium containing physiological concentrations of insulin improves oocyte growth and maturation after the IVC of goat early antral follicles.

  20. Comparison of mupirocin-based media for selective enumeration of bifidobacteria in probiotic supplements.

    PubMed

    Bunesova, Vera; Musilova, Sarka; Geigerova, Martina; Pechar, Radko; Rada, Vojtech

    2015-02-01

    An international standard already exists for the selective enumeration of bifidobacteria in milk products. This standard uses Transgalactosylated oligosaccharides (TOS) propionate agar supplemented with mupirocin. However, no such standard method has been described for the selective enumeration of bifidobacteria in probiotic supplements, where the presence of bifidobacteria is much more variable than in milk products. Therefore, we enumerated bifidobacteria by colony count technique in 13 probiotic supplements using three media supplemented with mupirocin (Mup; 100mg/l): TOS, Bifidobacteria selective medium (BSM) and modified Wilkins-Chalgren anaerobe agar with soya peptone (WSP). Moreover, the potential growth of bifidobacterial strains often used in probiotic products was performed in these media. All 13 products contained members of the genus Bifidobacterium, and tested mupirocin media were found to be fully selective for bifidobacteria. However, the type strain Bifidobacterium bifidum DSM 20456 and collection strain B. bifidum DSM 20239 showed statistically significant lower counts on TOS Mup media, compared to BSM Mup and WSP Mup media. Therefore, the TOS Mup medium recommended by the ISO standard cannot be regarded as a fully selective and suitable medium for the genus Bifidobacterium. In contrast, the BSM Mup and WSP Mup media supported the growth of all bifidobacterial species.

  1. Supplementation of maturation medium with L-carnitine improves cryo-tolerance of bovine in vitro matured oocytes.

    PubMed

    Chankitisakul, Vibuntita; Somfai, Tamas; Inaba, Yasushi; Techakumphu, Mongkol; Nagai, Takashi

    2013-03-01

    The objective was to determine the effects of adding L-carnitine (an enhancer of lipid metabolism) during IVM, on cryotolerance and developmental competence of bovine oocytes. Oocytes matured in the absence (control) or presence (0.6 mg/mL) of L-carnitine were subjected to IVF and embryo culture after Cryotop vitrification or nonvitrification at the metaphase stage of the second meiotic cell division. Cleavage and blastocyst formation rates, and inner cell mass and trophectoderm cell numbers were determined. Also, ATP content in IVM oocytes was measured and intracellular lipid droplets were observed (Nile red staining and confocal microscopy). L-carnitine had no significant effect on the rate of matured oocytes. Vitrification reduced (P < 0.05) mean (±SEM) rates of live oocytes both in control (80.6 ± 1.9%) and L-carnitine groups (82.7 ± 5.1%) compared with nonvitrified oocytes (100%). After IVF, cleavage rates of vitrified control and L-carnitine groups (56.5 ± 3.9% and 62.8 ± 5.1%, respectively) were significantly lower than those in nonvitrified control and L-carnitine groups (83.9 ± 4.2% and 84.3 ± 1.3%). After vitrification, blastocyst formation rate in the L-carnitine group (54.4 ± 5.2%) was significantly higher compared with the control (34.9 ± 4.4%), and did not significantly differ from those in nonvitrified control and L-carnitine groups (52.1 ± 4.2% and 52.8 ± 3.0%). The numbers and ratio of inner cell mass and trophectoderm cells in blastocysts did not differ significantly among groups. The ATP content in L-carnitine-treated oocytes tended to be higher compared with the control. Vitrification did not reduce ATP content in oocytes, irrespective of L-carnitine treatment. Treatment with L-carnitine dislocated lipid droplets from the peripheral area to the inner cytoplasm. In conclusion, L-carnitine supplementation during IVM redistributed lipid droplets in oocytes; if they survived vitrification, their developmental competence was similar to

  2. Inhibition of calcineurin by FK506 stimulates germinal vesicle breakdown of mouse oocytes in hypoxanthine-supplemented medium

    PubMed Central

    Wang, Li; Zhen, Yan-Hong; Liu, Xiao-Ming; Cao, Jing; Wang, Yan-Ling

    2017-01-01

    Calcineurin (CN) is a serine/threonine phosphatase which plays important roles in meiosis maturation in invertebrate oocytes; however, the role of CN in mouse oocytes is relatively unexplored. In this study, we examined the expression, localization and functional roles of CN in mouse oocytes and granulosa cells. The RT-PCR results showed that the β isoform of calcineurin A subunit (Cn A) expressed significantly higher than α and γ isoforms, and the expression of Cn Aβ mRNA obviously decreased in oocytes in which germinal vesicle breakdown (GVBD) occurred, while only B1 of calcineurin B subunit (Cn B) was detected in oocytes and stably expressed during oocytes maturation. The following fluorescence experiment showed that Cn A was mainly located in the nucleus of germinal vesicle (GV) stage oocytes and gruanlosa cells, and subsequently dispersed into the entire cytoplasm after GVBD. The decline of Cn A in oocytes suggested that it may play an important role in GVBD. To further clarify the role of calcineurin during meiotic maturation, FK506 (a calcineurin inhibitor) was used in the culture medium contained hypoxanthine (HX) which could keep mouse oocytes staying at GV stage. As expected, FK506 could induce a significant elevation of GVBD rate and increase the MPF level of denuded oocytes (DOs). Furthermore, FK506 could also play an induction role of GVBD of oocytes in COCs and follicles, and the process could be counteracted by MAPK kinase inhibitor (U0126). Above all, the results implied that calcineurin might play a crucial role in development of mouse oocytes and MPF and MAPK pathways are involved in this process. PMID:28243539

  3. Effects of supplementation of medium with different antioxidants during in vitro maturation of bovine oocytes on subsequent embryo production.

    PubMed

    Sovernigo, T C; Adona, P R; Monzani, P S; Guemra, S; Barros, Fda; Lopes, F G; Leal, Clv

    2017-03-10

    The aim of this study was to assess the effects of different antioxidants on the levels of reactive oxygen species (ROS) and glutathione (GSH) in oocytes during in vitro maturation (IVM), as well as on the production of embryos. Oocyte of slaughterhouse-derived cattle ovaries were placed in IVM with different antioxidants: quercetin (2 μM), cysteamine (100 μM), carnitine (0.5 mg/ml), vitamin C (50 μg/ml) or resveratrol (2 μM). Oocytes matured without any antioxidant supplementation were used as control. The oocytes were assessed for maturation rates and for ROS and GSH levels by fluorescence staining in 2',7'-dichlorodihydrofluorescein diacetate and Cell Tracker Blue, respectively. Embryo production was assessed in terms of cleavage, blastocysts and hatching rates and embryo cell numbers. The results expressed in arbitrary fluorescence units showed ROS reduction (p < .05) in the groups with quercetin (27.5 ± 3.4), vitamin C (27.1 ± 3.0) or resveratrol (28.1 ± 4.7), in comparison with those with cysteamine (34.9 ± 4.5), carnitine (34.6 ± 3.8) or to the control group (36.5 ± 5.2). GSH levels increased (p < .05) in cysteamine (63.5 ± 5.5) or carnitine (60.8 ± 4.4) groups in comparison with quercetin (52.7 ± 5.1), vitamin C (53.0 ± 3.8), resveratrol (53.1 ± 4.4) or to the control (49.6 ± 4.5). Nuclear maturation cleavage and hatched blastocysts rates did not differ (p > .05) between groups. However, blastocyst rates after in vitro fertilization in quercetin (53.5 ± 3.9%), vitamin C (52.1 ± 3.1%) resveratrol (54.2 ± 4.0%), cysteamine (52.4 ± 2.7%) or carnitine (54.2 ± 3.1%) groups were higher (p < .05) than in the control (47.2 ± 2.7%). Total cell numbers in embryos from the vitamin C, resveratrol, cysteamine or carnitine groups were higher than in quercetin and control groups, which were similar to each other. The results suggest that using antioxidants during IVM may reduce oxidative stress either

  4. Use of a long-chain triglyceride-restricted/medium-chain triglyceride-supplemented diet in a case of malonyl-CoA decarboxylase deficiency with cardiomyopathy.

    PubMed

    Footitt, E J; Stafford, J; Dixon, M; Burch, M; Jakobs, C; Salomons, G S; Cleary, M A

    2010-12-01

    Malonyl coenzyme A (CoA) decarboxylase (EC 4.1.1.9, MCD) deficiency, or malonic aciduria, is a rare inborn error of metabolism characterised by a variable phenotype of developmental delay, seizures, cardiomyopathy and acidosis. There is no consensus for dietary treatment in this condition. This case describes the effect of a long-chain triglyceride (LCT)-restricted/medium-chain triglyceride (MCT)-supplemented diet upon the progress of an affected child. A full-term Asian girl of birth weight 3590 g was screened for malonic aciduria after birth due to a positive family history. She had elevated urine malonic and methylmalonic acids and was presumably homozygous for a deleterious mutation in the MLYCD gene. Her echocardiography showed mild cardiomyopathy at 0.5 months of age, but heart function was good. She was treated with carnitine 100 mg/kg per day and continued a high-energy formula feed, as her growth was slow. At 3 months of age, echocardiography showed deteriorating cardiac function with a fractional shortening of 18%. She started an angiotensin-converting enzyme (ACE) inhibitor (Captopril). Over the next few months, her diet was altered to comprise 1.9% energy from LCT, 25% from MCT and the remainder carbohydrate. Cardiac function improved and was optimal at 23 months of age, with a fractional shortening of 28% and good systolic function. During a period of low MCT intake, her cardiac function was noted to deteriorate. This reversed and stabilised following reinstatement of the diet. This case of malonic aciduria with cardiomyopathy demonstrates improvement in cardiac function attributable to LCT-restricted/MCT-supplemented diet.

  5. Combined epidermal growth factor and hyaluronic acid supplementation of in vitro maturation medium and its impact on bovine oocyte proteome and competence.

    PubMed

    Ríos, G L; Buschiazzo, J; Mucci, N C; Kaiser, G G; Cesari, A; Alberio, R H

    2015-03-15

    The conditions for in vitro oocyte maturation impact on cytoplasmic and nuclear processes in the oocyte. These events are differentially influenced by the nature of the maturation inducer and the presence of intact cumulus in cumulus-oocyte complexes. Epidermal growth factor is the main growth factor promoting oocyte maturation. Also, hyaluronic acid (HA) produced by cumulus cells is known to be responsible for the correct structural and functional organization of the cumulus during oocyte maturation. Therefore, we evaluated the developmental competence of bovine oocytes matured in vitro in a maturation medium supplemented with both EGF and HA, compared to FSH and fetal bovine serum (FBS). In addition, the impact of IVM conditions on the proteomic profile of metaphase II bovine oocytes was analyzed by two-dimensional electrophoresis. Cumulus-oocyte complexes were matured in two media: (1) 10 ng/mL EGF, 15 μg/mL HA, and 100-μM cysteamine and (2) 0.01 UI/mL rh-FSH and 10% FBS. The percentages of first polar body and embryo production and the kinetics of embryo development and oocyte proteomic profiles were analyzed. Oocytes matured in the presence of EGF-HA showed an increase (6%, P < 0.05) in the percentage of polar body extrusion. The blastocyst rate was 3% (P < 0.05) higher in the FSH-FBS group, but no differences were found in the rate of expanded blastocyst neither in total embryo production between IVM conditions. Cleavage rate of oocytes matured with FSH-FBS was 5% higher (P < 0.05) with respect to EGF-HA-matured oocytes when evaluated 30 hours after fertilization. However, at Day 7, those inseminated oocytes that underwent division at a correct timing showed that although there are still early blastocysts in the FSH-FBS condition, EGF-HA embryos have developed completely into blastocysts. Still, the production rate of those embryos that achieved expansion was similar between both maturation conditions. On the other hand, noncleaved presumptive

  6. Pigments of fly agaric (Amanita muscaria).

    PubMed

    Stintzing, Florian; Schliemann, Willibald

    2007-01-01

    The complex pigment pattern of fly agaric (Amanita muscaria) cap skins has been studied by LC-DAD and mass spectrometry. Among the betaxanthins the corresponding derivatives of serine, threonine, ethanolamine, alanine, Dopa, phenylalanine and tryptophan are reported for the first time to contribute to the pigment pattern of fly agarics. Betalamic acid, the chromophoric precursor of betaxanthins and betacyanins, muscaflavin and seco-dopas were also detected. Furthermore, the red-purple muscapurpurin and the red muscarubrin were tentatively assigned while further six betacyanin-like components could not be structurally allocated. Stability studies indicated a high susceptibility of pigment extracts to degradation which led to rapid colour loss thus rendering a complete characterization of betacyanin-like compounds impossible at present. Taking into account these difficulties the presented results may be a starting point for a comprehensive characterization of the pigment composition of fly agarics.

  7. [Presumptive identification of Candida spp. and other clinically important yeasts: usefulness of Brilliance Candida Agar].

    PubMed

    Alfonso, Claudia; López, Mónica; Arechavala, Alicia; Perrone, María Del Carmen; Guelfand, Liliana; Bianchi, Mario

    2010-06-30

    Fungal infections caused by yeasts have increased during the last decades and invasive forms represent a serious problem for human health. Candida albicans is the species most frequently isolated from clinical samples. However, other emerging yeast pathogens are increasingly responsible for mycotic infections, and some of them are resistant to some antifungal drugs. Consequently, it is necessary to have methods that can provide a rapid presumptive identification at species level. Numerous chromogenic agar media have been shown to be of value as diagnostic tools. We have compared a chromogenic medium, Brilliance Candida Agar, with CHROMagar Candida, the chromogenic medium most used in our country. A multicentre study was conducted in 16 Hospitals belonging to the Mycology Net of Buenos Aires City Government. A total of 240 yeast isolates were included in this research. The new chromogenic agar showed results very similar to those obtained with CHROMagar Candida.

  8. Standard operating procedure to prepare agar phantoms

    NASA Astrophysics Data System (ADS)

    Souza, R. M.; Santos, T. Q.; Oliveira, D. P.; Souza, R. M.; Alvarenga, A. V.; Costa-Felix, R. P. B.

    2016-07-01

    Agar phantoms are widely used as soft tissue mimics and some preparation techniques are described in the literature. There are also standards that describe the recipe of a soft tissue mimicking material (TMM). However some details of manufacture process are not clearly defined. The standardization of the phantom's preparation can produce a metrological impact on the results of the acoustic properties measured. In this direction, this paper presents a standard operating procedure (SOP) to prepare the agar TMM described on the IEC 60601-237.

  9. Stable isotope ratios as a tool in microbial forensics--part 3. Effect of culturing on agar-containing growth media.

    PubMed

    Kreuzer-Martin, Helen W; Chesson, Lesley A; Lott, Michael J; Ehleringer, James R

    2005-11-01

    Stable isotope ratios of hydrogen and oxygen in microbes have been shown to be functions of the corresponding isotope ratios of the water with which the culture medium was prepared, and thus to contain a potential geographic signal. Water can evaporate from agar (solid) media during culturing, changing its isotope ratios. Here we describe the effect of drying on the isotope ratios of water extracted from agar media and the H and O stable isotope ratios ratios of Bacillus subtilis spores cultured on agar. The delta2H vs delta18O relationship of water in Petri dish agar was surprisingly constant during evaporation regardless of the ambient relative humidity, making it possible to calculate the approximate isotope ratios of the original water, even in significantly evaporated agar. The H stable isotope ratios of spores cultured on agar remained relatively unchanged as the agar dried, but the O ratio became significantly enriched.

  10. Surface migration of Staphylococcus xylosus on low-agar media.

    PubMed

    Dordet-Frisoni, Emilie; Gaillard-Martinie, Brigitte; Talon, Régine; Leroy, Sabine

    2008-05-01

    Staphylococcus xylosus is a commensal species commonly found on the skin of mammals, but also currently used as starter culture for meat fermentation. Most strains of this species colonize by forming a biofilm on abiotic surfaces. We show here that the majority of S. xylosus strains also exhibit extensive colony spreading on the surface of soft agar media. This phenomenon seemed to be independent of biofilm-forming ability. It occurred in different culture media and was dependent on temperature. Formation of a giant S. xylosus colony did not involve a biosurfactant. Microscopic observation showed that the front of the giant colony comprised a single layer of spacing cells with more packed cells in the median area. Supplementation of the soft media with DNase I increased S. xylosus colony spreading, indicating that extracellular DNA may be involved in limiting the phenomenon. The ability of S. xylosus to spread on semi-solid surfaces may constitute an advantage for surface colonization.

  11. Use of agar agar stabilized milled zero-valent iron particles for in situ groundwater remediation

    NASA Astrophysics Data System (ADS)

    Schmid, Doris; Velimirović, Milica; Wagner, Stephan; Micić Batka, Vesna; von der Kammer, Frank; Hofmann, Thilo

    2015-04-01

    A major obstacle for use of nanoscale zero-valent iron (nZVI) particles as a nontoxic material for effective in situ degradation of chlorinated aliphatic hydrocarbons (CAHs) is the high production cost. For that reason, submicro-scale milled zero-valent iron particles were recently developed (milled ZVI, UVR-FIA, Germany) by grinding macroscopic raw materials of elementary iron as a cheaper alternative to products produced by solid-state reduction. However, milled ZVI particles tend to aggregate and due to the rather large particle size (d50= 11.9 µm) also rapidly sediment. To prevent aggregation and consequently sedimentation of milled ZVI particles and therefore improve the mobility after in situ application, the use of a stabilizer is considered in literature as a most promising option. In this study, milled ZVI particles (1 g L-1 of particle concentration) were stabilized by environmentally friendly polymer agar agar (>0.5 g L-1), which had a positive impact on the milled ZVI stability. Sedimentation rate was significantly decreased by increasing the suspension viscosity. Column transport experiments were performed for bare and agar agar stabilized milled ZVI particles in commercially available fine grained quartz sand (DORSILIT® Nr.8, Gebrüder Dorfner GmbH Co, Germany) and different porous media collected from brownfields. The experiments were carried out under field relevant injection conditions of 100 m d-1. The maximal travel distance (LT) of less than 10 cm was determined for non-stabilized suspension in fine grained quartz sand, while agar agar (1 g L-1) stabilized milled ZVI suspension revealed LT of 12 m. Similar results were observed for porous media from brownfields showing that mobility of agar agar stabilized particle suspensions was significantly improved compared to bare particles. Based on the mobility data, agar agar stabilized milled zero-valent iron particles could be used for in situ application. Finally, lab-scale batch degradation

  12. Selective medium for isolation of Actinobacillus actinomycetemcomitans.

    PubMed Central

    Slots, J

    1982-01-01

    A selective medium, TSBV (tryptic soy-serum-bacitracin-vancomycin) agar, was developed for the isolation of Actinobacillus actinomycetemcomitans, TSBV agar contained (per liter) 40 g of tryptic soy agar, 1 g of yeast extract, 100 ml of horse serum. 75 mg of bacitracin, and 5 mg of vancomycin. The TSBV medium suppressed most oral species and permitted significantly higher recovery of A. actinomycetemcomitans than nonselective blood agar medium. The distinct colonial morphology and positive catalase reaction of A. actinomycetemcomitans easily distinguished this bacterium from Haemophilus aphrophilus, Capnocytophaga species, and a few other contaminating organisms. With the TSBV medium, even modestly equipped laboratories will be able to isolate and identify A. actinomycetemcomitans from clinical specimens. Images PMID:7068837

  13. Use of bile-esculin agar for rapid differentiation of Enterobacteriaceae.

    PubMed Central

    Lindell, S S; Quinn, P

    1975-01-01

    Bile-esculin agar has been used for several years for the presumptive identification of group D streptococci. All members of the Enterobacteriaceae family will also grow on this medium, but only certain ones can hydrolyze esculin to 6,7-dihydroxycoumarin, which reacts with iron to produce a characteristic blackening of the medium. One thousand and six cultures from clinical specimens representing 20 genera were isolated and identified. Heavy inocula from fresh pure culture isolates on heart infusion agar were placed on bile-esculin agar slants and incubated at 35 C. The slants were examined at 4 h and again at 18 h for esculin hydrolysis. Shigella, Salmonella, Arizona, Proteus mirabilis, Proteus morganii, Providencia alcalifaciens, and Providencia stuartii all produced negative results. Klebsiella pneumoniae, Enterobacter aerogenes, Serratia marcescens, and Serratia rubidaea produced a positive reaction in 4 h. The other remaining eight genera exhibited varying results. The use of this medium in conjunction with triple sugar iron-lysine iron agar has been of great value in differentiating the Klebsiella-Enterobacter-Serratia group from other Enterobacteriaceae. PMID:1176613

  14. Use of bile-esculin agar for rapid differentiation of Enterobacteriaceae.

    PubMed

    Lindell, S S; Quinn, P

    1975-05-01

    Bile-esculin agar has been used for several years for the presumptive identification of group D streptococci. All members of the Enterobacteriaceae family will also grow on this medium, but only certain ones can hydrolyze esculin to 6,7-dihydroxycoumarin, which reacts with iron to produce a characteristic blackening of the medium. One thousand and six cultures from clinical specimens representing 20 genera were isolated and identified. Heavy inocula from fresh pure culture isolates on heart infusion agar were placed on bile-esculin agar slants and incubated at 35 C. The slants were examined at 4 h and again at 18 h for esculin hydrolysis. Shigella, Salmonella, Arizona, Proteus mirabilis, Proteus morganii, Providencia alcalifaciens, and Providencia stuartii all produced negative results. Klebsiella pneumoniae, Enterobacter aerogenes, Serratia marcescens, and Serratia rubidaea produced a positive reaction in 4 h. The other remaining eight genera exhibited varying results. The use of this medium in conjunction with triple sugar iron-lysine iron agar has been of great value in differentiating the Klebsiella-Enterobacter-Serratia group from other Enterobacteriaceae.

  15. Comparison of Fecal Coliform Agar and Violet Red Bile Lactose Agar for Fecal Coliform Enumeration in Foods

    PubMed Central

    Leclercq, A.; Wanegue, C.; Baylac, P.

    2002-01-01

    A 24-h direct plating method for fecal coliform enumeration with a resuscitation step (preincubation for 2 h at 37 ± 1°C and transfer to 44 ± 1°C for 22 h) using fecal coliform agar (FCA) was compared with the 24-h standardized violet red bile lactose agar (VRBL) method. FCA and VRBL have equivalent specificities and sensitivities, except for lactose-positive non-fecal coliforms such as Hafnia alvei, which could form typical colonies on FCA and VRBL. Recovery of cold-stressed Escherichia coli in mashed potatoes on FCA was about 1 log unit lower than that with VRBL. When the FCA method was compared with standard VRBL for enumeration of fecal coliforms, based on counting carried out on 170 different food samples, results were not significantly different (P > 0.05). Based on 203 typical identified colonies selected as found on VRBL and FCA, the latter medium appears to allow the enumeration of more true fecal coliforms and has higher performance in certain ways (specificity, sensitivity, and negative and positive predictive values) than VRBL. Most colonies clearly identified on both media were E. coli and H. alvei, a non-fecal coliform. Therefore, the replacement of fecal coliform enumeration by E. coli enumeration to estimate food sanitary quality should be recommended. PMID:11916678

  16. Effects of extracellular matrix proteins on macrophage differentiation, growth, and function: comparison of liquid and agar culture systems

    NASA Technical Reports Server (NTRS)

    Armstrong, J. W.; Chapes, S. K.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Both spaceflight and skeletal unloading suppress the haematopoietic differentiation of macrophages (Sonnenfeld et al., Aviat. Space Environ. Med., 61:648-653, 1990; Armstrong et al., J. Appl. Physiol., 75:2734-2739, 1993). The mechanism behind this reduction in haematopoiesis has yet to be elucidated. However, changes in bone marrow extracellular matrix (ECM) may be involved. To further understand the role of ECM products in macrophage differentiation, we have performed experiments evaluating the effects of fibronectin, laminin, collagen type I, and collagen type IV on macrophage development and function. Bone marrow-derived macrophages cultured on four different ECM substrates in liquid culture medium showed less growth than those cultured on plastic. Significant morphological differences were seen on each of the substrates used. Phenotypically and functionally, as measured by class II major histocompatibility molecule (MHCII) expression, MAC-2 expression, and the secretion of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha), these macrophages were similar. In contrast, bone marrow-derived macrophages cultured in suspension, using agar, showed no difference in growth when exposed to ECM proteins. However, IL-6 and TNF-alpha secretion was affected by fibronectin, laminin, collagen type I, and collagen type IV in a concentration-dependent manner. We conclude that the ECM products fibronectin, laminin, collagen type I, and collagen type IV have profound effects on macrophage development and function. Additionally, we suggest that an ECM-supplemented agar culture system provides an environment more analogous to in vivo bone marrow than does a traditional liquid culture system.

  17. Possible influence of surfactants and proteins on the efficiency of contact agar microbiological surface sampling.

    PubMed

    Deckers, Sylvie M; Sindic, Marianne; Anceau, Christine; Brostaux, Yves; Detry, Jean G

    2010-11-01

    Agar contact microbiological sampling techniques, based on a transfer of the microorganisms present on a surface to a culture medium, are widely used to assess and control surface cleanliness and to evaluate microbial contamination levels. The effectiveness of these techniques depends on many environmental parameters that influence the strength of attachment of the bacteria to the surface. In the present study, stainless steel and high density polyethylene surfaces were inoculated with known concentrations of Staphylococcus epidermidis. Following an experimental design, the surfaces were sampled with different types of replicate organism direct agar contact plates and Petrifilm; results indicated that recovery rates were influenced by the presence of egg white albumin or Tween 80 in the inoculum solutions or by the introduction of surfactants into the contact agar of the microbiological sampling techniques. The techniques yielded significantly different results, depending on sampling conditions, underlining the need for a standardization of laboratory experiments to allow relevant comparisons of such techniques.

  18. Eradication of bovine leukemia virus infection in commercial dairy herds using the agar gel immunodiffusion test.

    PubMed Central

    Shettigara, P T; Samagh, B S; Lobinowich, E M

    1986-01-01

    Demands for bovine leukemia virus test negative breeding cattle and for semen from bovine leukemia virus test negative bulls by several countries have encouraged the eradication of bovine leukemia virus infection from selected herds in Canada. This project was undertaken to evaluate the suitability of the agar gel immunodiffusion test, standardized to detect anti-bovine leukemia virus glycoprotein antibodies, for eradication of bovine leukemia virus from commercial dairy herds. Of nine participating herds, the prevalence rate of bovine leukemia virus infection was low (less than 10%) in three, medium (11-30%) in four and high (greater than 30%) in two. The herds were tested by the agar gel immunodiffusion test, reactors were removed and the herds were then retested at regular intervals. The results indicate that it is possible to eliminate bovine leukemia virus infection from the herds after two to three cycles of agar gel immunodiffusion tests and prompt removal of the reactors. PMID:3019498

  19. Use of Rambach Propylene Glycol Containing Agar for identification of Salmonella spp.

    PubMed

    Gruenewald, R; Henderson, R W; Yappow, S

    1991-10-01

    When grown on Rambach Propylene Glycol Containing Agar (Rambach agar), 216 of 230 (93.9%) Salmonella organisms isolated from patients and 54 of 62 (87.1%) Salmonella stock cultures produced a crimson-colored growth. Of the 14 clinical Salmonella isolates which displayed colors other than crimson, 8 were Salmonella typhi, 2 were Salmonella paratyphi A, and 4 belonged to other commonly isolated serotypes. All eight Salmonella stock cultures which failed to produce a crimson color belonged to rarely isolated serotypes. In contrast, of 83 non-Salmonella stock cultures distributed among 29 bacterial species, none produced a crimson color. These results suggest that while Rambach agar cannot preidentify S. typhi and S. paratyphi A, the medium can be used for the presumptive identification and can assist in the definitive identification of the overwhelming majority of Salmonella isolates.

  20. Enhancement by sodium chloride of the selectivity of thiosulfate citrate bile salts sucrose agar for isolating Vibrio cholerae biotype El Tor.

    PubMed Central

    Morris, G K; DeWitt, W E; Gangarosa, E J; McCormack, W M

    1976-01-01

    In this study we utilized the salt-tolerant characteristics of vibrios to develop a more selective medium by addition of NaCl to thiosulfate citrate bile salts sucrose (TCBS) agar. The effect of adding salt to TCBS agar varied greatly among brands of TCBS agar and between lots of the same brand. The addition of salt at concentrations as high as 1.5% (2.5% total NaCl) caused the inhibition of growth of three species of commonly encountered normal bowel flora and one strain of classical Vibrio cholerae but did not compromise the use of TCBS agar for isolation of V. cholerae biotype El Tor. PMID:965476

  1. Mass production of spores of lactic acid-producing Rhizopus oryzae NBRC 5384 on agar plate.

    PubMed

    Yamane, Tsuneo; Tanaka, Ryosuke

    2013-01-01

    Mass production of sporangiospores (spores) of Rhizopus oryzae NBRC 5384 (identical to NRRL 395 and ATCC 9363) on potato-dextrose-agar medium was studied aiming at starting its L(+)-lactic acid fermentation directly from spore inoculation. Various parameters including harvest time, sowed spore density, size of agar plate, height of air space, and incubation mode of plate (agar-on-bottom or agar-on-top) were studied. Ordinarily used shallow Petri dishes were found out to be unsuitable for the full growth of R. oryzae sporangiophores. In a very wide range of the sowed spore density, the smaller it was, the greater the number of the harvested spores was. It was also interesting to find out that R. oryzae grown downward vertically with a deep air space in an agar-on-top mode gave larger amount of spores than in an agar-on-bottom mode at 30°C for 7-day cultivation. Scale-up of the agar plate culture from 26.4 to 292 cm(2) was studied, resulting in the proportional relationship between the number of the harvested spores/plate and the plate area in the deep Petri dishes. The number of plates of 50 cm in diameter needed for 100 m(3) industrial submerged fermentation started directly from 2 × 10(5) spores/mL inoculum size was estimated as about 6, from which it was inferred that such a fermentation would be feasible. Designing a 50 cm plate and a method of spreading and collecting the spores were suggested. Bioprocess technological significance of the "full-scale industrial submerged fermentation started directly from spore inoculation omitting pre-culture" has been discussed.

  2. Evaluation of CP Chromo Select Agar for the enumeration of Clostridium perfringens from water.

    PubMed

    Manafi, Mammad; Waldherr, Kerstin; Kundi, Michael

    2013-10-01

    The European Directive on drinking water quality has included mCP agar as the reference method for recovering Clostridium perfringens from drinking waters. In the present study, three media (mCP, TSCF and CP Chromo Select Agar) were evaluated for recovery of C. perfringens in different surface water samples. Out of 139 water samples, using a membrane filtration technique, 131 samples (94.2%) were found to be presumptively positive for C. perfringens in at least one of the culture media. Green colored colonies on CP Chromo Select Agar (CCP agar) were counted as presumptive C. perfringens isolates. Out of 483 green colonies on CCP agar, 96.3% (465 strains, indole negative) were identified as C. perfringens, and 15 strains (3.1%) were indole positive and were identified as Clostridium sordellii, Clostridium bifermentans or Clostridium tetani. Only 3 strains (0.6%) gave false positive results and were identified as Clostridium fallax, Clostridium botulinum, and Clostridium tertium. Variance analysis of the data obtained shows statistically no significant differences in the counts obtained between media employed in this work. The mCP method is very onerous for routine screening and bacterial colonies could not be used for further biochemical testing. The colonies on CCP and TSCF were easy to count and subculture for confirmation tests. TSCF detects sulfite-reducing clostridia, including species other than C. perfringens, and in some cases excessive blackening of the agar frustrated counting of the colonies. If the contamination was too high, TSCF did not consistently produce black colonies and as a consequence, the colonies were white and gave false negative results. On the other hand, the identification of typical and atypical colonies isolated from all media demonstrated that CCP agar was the most useful medium for C. perfringens recovery in water samples.

  3. Agar media that indicate acid production from sorbitol by oral microorganisms.

    PubMed Central

    Kalfas, S; Edwardsson, S

    1985-01-01

    Two varieties of agar medium (Trypticase [BBL Microbiology Systems]-serum-sorbitol-bromcresol purple agar [TSSB] and Trypticase-blood-sorbitol-CaCO3 agar [TBSCa]) indicating microbial acid production from sorbitol were tested. The media were devised for use in studies on the prevalence of sorbitol-fermenting human oral microorganisms incubated in an anaerobic or microaerophilic atmosphere containing 5 to 6% CO2. TSSB contains bromcresol purple as the pH indicator and NaHCO3 as the main buffering salt. TBSCa contains CaCO3 as both the buffering salt and the indicator of acid production. The growth yield of pure cultures of oral microorganisms on TBSCa was shown to equal that on blood agar incubated under similar conditions. TSSB inhibited the growth of several bacteria to various extents. The recovery of sorbitol-fermenting microorganisms from oral specimens was the greatest when the specimens were assayed with TBSCa. The poorer results obtained with TSSB were mainly due to the decoloration of the pH indicator in this medium and the presence of greater numbers of sorbitol false-positive colonies. Images PMID:2933424

  4. Ultrasonic backscatter coefficients for weakly scattering, agar spheres in agar phantoms

    PubMed Central

    King, Michael R.; Anderson, Janelle J.; Herd, Maria-Teresa; Ma, Darryl; Haak, Alexander; Wirtzfeld, Lauren A.; Madsen, Ernest L.; Zagzebski, James A.; Oelze, Michael L.; Hall, Timothy J.; O’Brien, William D.

    2010-01-01

    Applicability of ultrasound phantoms to biological tissue has been limited because most phantoms have generally used strong scatterers. The objective was to develop very weakly scattering phantoms, whose acoustic scattering properties are likely closer to those of tissues and then compare theoretical simulations and experimental backscatter coefficient (BSC) results. The phantoms consisted of agar spheres of various diameters (nominally between 90 and 212 μm), containing ultrafiltered milk, suspended in an agar background. BSC estimates were performed at two institutions over the frequency range 1–13 MHz, and compared to three models. Excellent agreement was shown between the two laboratory results as well as with the three models. PMID:20707460

  5. Highly selective medium for isolation of Listeria monocytogenes from food.

    PubMed

    al-Zoreky, N; Sandine, W E

    1990-10-01

    A new selective medium (Al-Zoreky-Sandine listeria medium [ASLM]) was formulated to recover Listeria monocytogenes from food specimens; the medium completely inhibited common food microflora. Recognition of Listeria colonies is evident by black discoloration of the medium due to esculin hydrolysis without need for special illuminating equipment. The medium contains acriflavin, ceftazidime, and moxalactam as selective agents. Compared with Listeria Selective Agar, ASLM was equally effective in recovering L. monocytogenes. However, ASLM inhibited micrococci, enterococci, and gram-negative bacteria, especially a strain that mimicked L. monocytogenes on Listeria Selective Agar. The new medium was able to recover heat injured cells with only 15% less count than the nonselective medium.

  6. Agar plate freezing assay for the in situ selection of transformed ice nucleating bacteria.

    PubMed

    Anastassopoulos, Elias

    2006-10-01

    An agar plate freezing assay is described based on the incorporation of fluorescein dye in agar medium. Upon addition of fluorescein the medium becomes transparent. This facilitates the monitoring of the ice nucleation event in vivo and the subsequent in situ selection of transformed ice nucleating bacteria. In comparison with known assays for the screening of transformants, the proposed assay is very accurate and reproducible. It may be applied in environmental samples screening for ice nucleating organisms, or in cDNA or genomic libraries for identifying novel ice nucleation genes. It may also prove useful in comparative studies of the ice nucleation activity, e.g. in directed evolution experiments involving ice nucleation genes.

  7. Biological treatment of textile dyes by agar-agar immobilized consortium in a packed bed reactor.

    PubMed

    Patel, Yogesh; Gupte, Akshaya

    2015-03-01

    The decolorization of Acid Maroon V was investigated using bacterial consortium EDPA containing Enterobacter dissolvens AGYP1 and Pseudomonas aeruginosa AGYP2 immobilized in different entrapment matrices. The consortium displayed 96% removal of dye (100 mg/l) within 6 h when immobilized in agar-agar. Under optimum concentrations of agar-agar (3.0% w/v) and cell biomass (0.9 g% w/v), the consortium displayed decolorization for 18 successive batches of Acid Maroon V and also decolorized 14 other different textile dyes. A packed bed reactor under batch mode showed 89% decolorization of dye after 56 repetitive cycles. Under continuous flow mode, maximum color removal was achieved with bed length of 36 cm, hydraulic retention time of 2.66 h, and dye concentration of 100 mg/l. Additionally, the reactor decolorized relatively higher concentrations (100-2000 mg/l) of dye. The synthetic dye wastewater containing five textile dyes was decolorized 92% with 62% COD reduction using an immobilized consortium.

  8. A selective and differential medium for Vibrio harveyi.

    PubMed Central

    Harris, L; Owens, L; Smith, S

    1996-01-01

    A new medium, termed Vibrio harveyi agar, has been developed for the isolation and enumeration of V. harveyi. It is possible to differentiate V. harveyi colonies from the colonies of strains representing 15 other Vibrio species with this medium. This medium has been shown to inhibit the growth of two strains of marine Pseudomonas spp. and two strains of marine Flavobacterium spp. but to allow the growth of Photobacterium strains. Colonies displaying typical V. harveyi morphology were isolated from the larval rearing water of a commercial prawn hatchery with V. harveyi agar as a primary isolation medium and were positively identified, by conventional tests, as V. harveyi. This agar displays great potential as a primary isolation medium and offers significant advantages over thiosulfate-citrate-bile salts-sucrose agar as a medium for differentiating V. harveyi from other marine and estuarine Vibrio species. PMID:8795252

  9. Screening fungicides for use in fish culture: Evaluation of the agar plug transfer, cellophane transfer, and agar dilution methods

    USGS Publications Warehouse

    Bailey, Tom A.

    1983-01-01

    The reliability, reproducibility, and usefulness of three screening methods -- the cellophane transfer, the agar plug transfer, and the agar dilution -- to screen aquatic fungicides were evaluated. Achlya flagellata and Saprolegnia hypogyna were exposed to 1, 10, and 100 mg/L of malachite green to test each method. The cellophane transfer and agar plug transfer techniques had similar reliability and reproducibility in rating fungicidal activity, and were both superior to the agar dilution technique. The agar plug transfer and agar dilution techniques adequately projected in vivo activity of malachite green, but the cellophane transfer technique overestimated its activity. Overall, the agar plug transfer technique most accurately rated the activity of malachite green and was the easiest test to perform. It therefore appears to be the method of choice for testing aquatic fungicides.

  10. An Agar-Based Method for Plating Marine Protozoan Parasites of the Genus Perkinsus

    PubMed Central

    Cold, Emma R.; Freyria, Nastasia J.; Martínez Martínez, Joaquín; Fernández Robledo, José A.

    2016-01-01

    The genus Perkinsus includes protozoan parasites of mollusks responsible for losses in the aquaculture industry and hampering the recovery of natural shellfish beds worldwide, and they are a key taxon for understanding intracellular parasitism adaptations. The ability to propagate the parasite in liquid media, in the absence of the host, has been crucial for improving understanding of its biology; however, alternative techniques to grow the parasite are needed to explore other basic aspects of the Perkinsus spp. biology. We optimized a DME: Ham’s F12–5% FBS- containing solid agar medium for plating Perkinsus marinus. This solid medium supported trophozoite propagation both by binary fission and schizogony. Colonies were visible to the naked eye 17 days after plating. We tested the suitability of this method for several applications, including the following: 1) Subcloning P. marinus isolates: single discrete P. marinus colonies were obtained from DME: Ham’s F12–5% FBS– 0.75% agar plates, which could be further propagated in liquid medium; 2) Subcloning engineered Perkinsus mediterraneus MOE[MOE]: GFP by streaking cultures on plates; 3) Chemical susceptibility: Infusing the DME: Ham’s F12–5% FBS– 0.75% agar plates with triclosan resulted in inhibition of the parasite propagation in a dose-dependent manner. Altogether, our plating method has the potential for becoming a key tool for investigating diverse aspects of Perkinsus spp. biology, developing new molecular tools, and for biotechnological applications. PMID:27149378

  11. An Agar-Based Method for Plating Marine Protozoan Parasites of the Genus Perkinsus.

    PubMed

    Cold, Emma R; Freyria, Nastasia J; Martínez Martínez, Joaquín; Fernández Robledo, José A

    2016-01-01

    The genus Perkinsus includes protozoan parasites of mollusks responsible for losses in the aquaculture industry and hampering the recovery of natural shellfish beds worldwide, and they are a key taxon for understanding intracellular parasitism adaptations. The ability to propagate the parasite in liquid media, in the absence of the host, has been crucial for improving understanding of its biology; however, alternative techniques to grow the parasite are needed to explore other basic aspects of the Perkinsus spp. biology. We optimized a DME: Ham's F12-5% FBS- containing solid agar medium for plating Perkinsus marinus. This solid medium supported trophozoite propagation both by binary fission and schizogony. Colonies were visible to the naked eye 17 days after plating. We tested the suitability of this method for several applications, including the following: 1) Subcloning P. marinus isolates: single discrete P. marinus colonies were obtained from DME: Ham's F12-5% FBS- 0.75% agar plates, which could be further propagated in liquid medium; 2) Subcloning engineered Perkinsus mediterraneus MOE[MOE]: GFP by streaking cultures on plates; 3) Chemical susceptibility: Infusing the DME: Ham's F12-5% FBS- 0.75% agar plates with triclosan resulted in inhibition of the parasite propagation in a dose-dependent manner. Altogether, our plating method has the potential for becoming a key tool for investigating diverse aspects of Perkinsus spp. biology, developing new molecular tools, and for biotechnological applications.

  12. Automatic Surface Inoculation of Agar Trays1

    PubMed Central

    Wilkins, Judd R.; Mills, Stacey M.; Boykin, Elizabeth H.

    1972-01-01

    A machine is described which automatically inoculates a plastic tray containing agar media with a culture by use of either a conventional inoculating loop or a cotton swab. Isolated colonies were obtained with an inoculating loop when a heavy inoculum (109 cells/ml) was used or with a cotton swab when a light inoculum (ca. 104 cells/ml) was used. Trays containing combinations of differential or selective media were used to (i) separate mixtures of gram-positive and gram-negative bacteria, (ii) facilitate isolation of organisms from clinical specimens, and (iii) compare colony growth characteristics of pure cultures. The design of the machine is simple, it is easy to use, and it relieves the operator from the manual task of streaking cultures. Images PMID:16349943

  13. Poisoning with brown fly agaric, Amanita regalis.

    PubMed

    Elonen, E; Tarssanen, L; Härkönen, M

    1979-01-01

    Three patients ate different amounts of a common northern mushroom, brown fly agaric, Amanita regalis. All of them believed they had eaten delicious parasol mushrooms, Macrolepiota procera. The symptoms of poisoning began 1--2 hours after ingestion of the mushrooms. All the patients had marked gastrointestinal symptoms: nausea and heavy vomiting. Two had central nervous system manifestations and cholinergic symptoms: hallucinations, confusion, or loss of consciousness as well as copious salivation, or sweating. All patients recovered within 4--24 hours without any damage to liver, kidneys or central nervous system. It seems that cooking the mushrooms does not completely neutralize the toxic agents of Amanita regalis. The analysis of fried mushrooms shows that it may be possible to identify mushrooms reliably from the remains of a meal.

  14. Equivalency testing of TTC Tergitol 7 agar (ISO 9308-1:2000) with five culture media for the detection of E. coli in water samples in Greece.

    PubMed

    Mavridou, A; Smeti, E; Mandilara, G; Mandilara, G; Boufa, P; Vagiona-Arvanitidou, M; Vantarakis, A; Vassilandonopoulou, G; Pappa, O; Roussia, V; Tzouanopoulos, A; Livadara, M; Aisopou, I; Maraka, V; Nikolaou, E; Mandilara, G

    2010-01-01

    In this study ten laboratories in Greece compared the performance of reference method TTC Tergitol 7 Agar (with the additional test of beta-glucuronidase production) with five alternative methods, to detect E. coli in water, in line with European Water Directive recommendations. The samples were prepared by spiking drinking water with sewage effluent following a standard protocol. Chlorinated and non-chlorinated samples were used. The statistical analysis was based on the mean relative difference of confirmed counts and was performed in line with ISO 17994. The results showed that in total, three of the alternative methods (Chromocult Coliform agar, Membrane Lauryl Sulfate agar and Trypton Bilex-glucuronidase medium) were not different from TTC Tergitol 7 agar (TTC Tergitol 7 agar vs Chromocult Coliform agar, 294 samples, mean RD% 5.55; vs MLSA, 302 samples, mean RD% 1; vs TBX, 297 samples, mean RD% -2.78). The other two alternative methods (Membrane Faecal coliform medium and Colilert 18/ Quantitray) gave significantly higher counts than TTC Tergitol 7 agar (TTC Tergitol 7 agar vs MFc, 303 samples, mean RD% 8.81; vs Colilert-18/Quantitray, 76 samples, mean RD% 18.91). In other words, the alternative methods generated performance that was as reliable as, or even better than, the reference method. This study will help laboratories in Greece overcome culture and counting problems deriving from the EU reference method for E. coli counts in water samples.

  15. [An improved differential medium, CA medium, for differentiating Shigella].

    PubMed

    Tokoro, M; Nagano, I; Goto, K; Nakamura, A

    1990-07-01

    We devised a Citrate-Acetate (CA) medium for rapidly differentiating Shigella. The medium consisted of 3.0 g of sodium citrate, 2.0 g of sodium acetate, 0.2 g of glucose, 1.0 g of dipotassium phosphate, 1.0 g of mono ammonium phosphate, 0.2 g of magnesium sulfate, 5.0 g of sodium chloride, 0.08 g of brom thymol blue, 15.0 g of agar, and 1000 ml of distilled water. An evaluation was made of the CA medium, for the rapid differentiation of 23 Shigella strains, 129 Escherichia coli strains and 130 isolates, that formed colourless colonies suspected to be Shigella on SS agar plate, from feces of healthy people. The results obtained were as follows 1) On the CA medium, all Shigella strains did not grow and there was no change in colour. 2) Positive growth rates of E. coli strains after incubation for 24 hr at 37 degrees C on CA medium, sodium acetate medium (Acet) and Christensen citrate medium (C-Cit) were 96.0%, 95.2% and 28.0%, respectively. Therefore, the positive growth rate of E. coli strains after incubation for 24 hr on CA medium was significantly higher (p less than 0.01) than that on C-Cit medium. 3) Positive growth rates of isolates after incubation for 24 hr at 37 degrees C on CA medium, Acet medium and C-Cit medium were 95.4%, 83.1% and 71.5%, respectively. Therefore, the positive growth rates of isolates after incubation for 24 hr on CA medium was significantly higher (p less than 0.01) than that on Acet medium and C-Cit medium.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. CHROMagar Yersinia, a New Chromogenic Agar for Screening of Potentially Pathogenic Yersinia enterocolitica Isolates in Stools

    PubMed Central

    Renaud, Nicolas; Lecci, Laetitia; Courcol, René J.; Simonet, Michel

    2013-01-01

    CHROMagar Yersinia (CAY) is a new chromogenic medium for the presumptive detection of virulent Yersinia enterocolitica in stools. Based on a comparative analysis of 1,494 consecutive stools from hospitalized patients, CAY was found to be just as sensitive as the reference medium (cefsulodin-irgasan-novobiocin agar) but was significantly more specific and had a very low false-positive rate. CAY reduces the workload (and thus costs) for stool analysis and can therefore be recommended for routine laboratory use. PMID:23363840

  17. A new selective medium for isolating Pseudomonas spp. from water.

    PubMed Central

    Krueger, C L; Sheikh, W

    1987-01-01

    A new medium, pseudomonas selective isolation agar, was developed to isolate Pseudomonas spp. from water. It consists of 350 micrograms of nitrofurantoin per ml and 2 micrograms of crystal violet per ml in a nutrient agar base. It is more selective for Pseudomonas spp. than are available commercial media. Its ingredients are inexpensive and readily available, and it is easy to prepare. PMID:3579287

  18. Antimicrobial susceptibility of Erysipelothrix rhusiopathiae isolated from pigs in Southern Japan with a modified agar dilution method.

    PubMed

    Chuma, Takehisa; Kawamoto, Toshio; Shahada, Francis; Fujimoto, Hideki; Okamoto, Karoku

    2010-05-01

    The determination of antimicrobial minimum inhibitory concentration (MIC) in Erysipelothrix rhusiopathiae by using the agar dilution method has not been covered by the Clinical and Laboratory Institute (CLSI). Only the broth microdilution method has been outlined. This report describes a modification of the agar dilution procedure for E. rhusiopathiae using Trypto-soy agar supplemented with 0.1% Tween 80 and incubation in ambient air at 37 degrees C for 24 hr. The MICs of the assay were in agreement with those of the broth microdilution method recommended by the CLSI. Antimicrobial susceptibility test was performed using this method for 149 E. rhusiopathiae isolates from 2 meat processing plants in Kagoshima Prefecture during the period of April 2004 to March 2005. The number of strains resistant to oxytetracycline, erythromycin, lincomycin, ofloxacin and enrofloxacin were 56 (37.6%), 4 (2.7%), 18 (12.1%), 21 (14.1%) and 19 (12.8%), respectively. All strains were susceptible to ampicillin.

  19. Supplementation of medium with diammonium hydrogen phosphate enhanced the D-lactate dehydrogenase levels leading to increased D-lactic acid productivity.

    PubMed

    Singhvi, Mamata; Jadhav, Akanksha; Gokhale, Digambar

    2013-10-01

    The production of D-lactic acid by Lactobacillus lactis RM2-24 was investigated using modified media to increase the efficiency of the fermentation process. The results indicated that the addition of 5 g/l peptone and 1 g/l (NH4)2HPO4 enhanced D-lactic acid production by 32%, as compared to that obtained from non supplemented media, with a productivity of 3.0 g/l/h. Lactate dehydrogenase (LDH) expression profile in these different media was studied which resulted in appearance of additional LDH isoform produced by cells when they were grown in HSYE supplemented with (NH4)2HPO4. The additional LDH appears to be L-LDH contributing to production of L-lactic acid in the fermented broth. This is totally new information in the lactic acid fermentation and could be very useful to industries engaged in D-lactic acid production.

  20. De novo fatty acid biosynthesis and elongation in very long-chain acyl-CoA dehydrogenase-deficient mice supplemented with odd or even medium-chain fatty acids.

    PubMed

    Tucci, Sara; Behringer, Sidney; Spiekerkoetter, Ute

    2015-11-01

    An even medium-chain triglyceride (MCT)-based diet is the mainstay of treatment in very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency (VLCADD). Previous studies with magnetic resonance spectroscopy have shown an impact of MCT on the average fatty acid chain length in abdominal fat. We therefore assume that medium-chain fatty acids (MCFAs) are elongated and accumulate in tissue as long-chain fatty acids. In this study, we explored the hepatic effects of long-term supplementation with MCT or triheptanoin, an odd-chain C7-based triglyceride, in wild-type and VLCAD-deficient (VLCAD(-/-) ) mice after 1 year of supplementation as compared with a control diet. The de novo biosynthesis and elongation of fatty acids, and peroxisomal β-oxidation, were quantified by RT-PCR. This was followed by a comprehensive analysis of hepatic and cardiac fatty acid profiles by GC-MS. Long-term application of even and odd MCFAs strongly induced de novo biosynthesis and elongation of fatty acids in both wild-type and VLCAD(-/-) mice, leading to an alteration of the hepatic fatty acid profiles. We detected de novo-synthesized and elongated fatty acids, such as heptadecenoic acid (C17:1n9), eicosanoic acid (C20:1n9), erucic acid (C22:1n9), and mead acid (C20:3n9), that were otherwise completely absent in mice under control conditions. In parallel, the content of monounsaturated fatty acids was massively increased. Furthermore, we observed strong upregulation of peroxisomal β-oxidation in VLCAD(-/-) mice, especially when they were fed an MCT diet. Our data raise the question of whether long-term MCFA supplementation represents the most efficient treatment in the long term. Studies on the hepatic toxicity of triheptanoin are still ongoing.

  1. In vitro growth and organogenesis of Prosopis farcta plantlets (Fabaceae, Mimosoideae) in culture medium supplemented with various concentrations of Ca++ and Na+.

    PubMed

    Stambouli, S; Bouzid, S; Dutuit, P; Harzallah-Skhiri, Fethia

    2012-03-01

    The objective of this study was to vary the mineral composition of the culture medium of Prosopis farcta seedlings per addition of Na+ and Ca++ ions with the aim to identify the culture media which support the growth and/or the expression of the in vitro plant organogenesis. The Na+ and Ca++ ions were added in the culture medium in various concentrations by taking the Gamborg medium, in which macroelements were diluted 10 times, as the basic one. After two months of culture, parameters relating to the vegetative development of plant seedlings and to the various expressions of organogenesis were measured. Weak concentrations in sodium and calcium ions as well as a weak concentration in Ca++ (0.1 mM) with 50 mM in Na+ support the best vegetative development of the plantlets. The most important percentage of plant seedlings presenting a bud initiation was obtained on a medium containing 0.1 mM of Na+ and 50 mM of Ca++. Our study defined several media likely to support in vitro development of Prosopis farcta plantlets allowing the selection of salt tolerant plants or cellular lines. Some other media were chosen for improving micropropagation of the species without adding growth substances.

  2. Gentamicin-Based Medium for the Isolation of Group D Streptococci and Application of the Medium to Water Analysis †

    PubMed Central

    Donnelly, L. Scott; Hartman, Paul A.

    1978-01-01

    Gentamicin-thallous-carbonate (GTC) medium contained (per liter): 40.0 g of Trypticase soy agar, 5.0 g of KH2PO4, 2.0 g of NaHCO2, 1.0 g of glucose, 1.0 g of esculin, 0.5 g of thallous acetate (TA), 0.5 g of ferric citrate, 0.75 ml of Tween 80, and 2.5 mg of gentamicin sulfate. The NaHCO3 (20 ml of a 10% solution that had been heated to boiling) was added after sterilization of the basal medium. The spread plate technique was used to compare GTC agar with Pfizer selective enterococcus, TA, and KF agars by using sewage as well as bovine and swine fecal samples. Significantly greater numbers of group D streptococci were recovered on GTC agar than on Pfizer selective enterococcus or KF agars, within and over all samples. Higher counts also were obtained on GTC than on TA agar, but the differences were not statistically significant. The percentage of false positives was about the same for all four media. Samples of riverwater also were plated on GTC, TA, and KF agars, and significantly higher recoveries were obtained with GTC agar. GTC agar was superior to the other media examined primarily because of increased recoveries of Streptococcus bovis and S. equinus; other advantages of GTC agar were large colony size and short (24-h) incubation period. The percentage of false positives from riverwater was 13% for GTC agar and 0% for TA and KF agars; therefore, confirmation would be necessary when GTC agar is used with some types of environmental samples. PMID:416754

  3. Selected elements in fly agaric Amanita muscaria.

    PubMed

    Falandysz, J; Kunito, T; Kubota, R; Lipka, K; Mazur, A; Falandysz, Justyna J; Tanabe, S

    2007-09-01

    Concentrations of Ag, Al, Ba, Ca, Cd, Co, Cu, Cr, Cs, Fe, Ga, Hg, K, Mg, Mn, Mo, Na, Pb, Rb, Se, Sb, Sr, V, Tl and Zn have been determined in the whole fruiting bodies, as well as separately in caps and stalks, of fly agaric collected from three geographically distant sites in northern part of Poland. The elements were determined using ICP-MS, ICP-OES, HG-AAS and CV-AAS, respectively. For elements such as Al, Ba, Cr, Fe, Ga, Mo, Mn, Pb, Sb, Sr, Tl, and V concentrations were similar in the caps and stalks, respectively, and for K, Zn, Ag, Ca, Cd, Cu, Hg, Mg, Rb and Se were greater in the caps, while for Co, Cs and Na in the stalks. For Ag, Al, Ba, Ca, Cd, Co, Cr, Cs, Fe, Ga, Hg, Mn, Mo, Pb, Rb, Sb, Sr, Tl and V concentration in the caps showed spatial variations (P<0.05), while for Cu, K, Mg, Na, Se and Zn was independent of the site. The elements such as K with median or mean in the caps between 37,000 and 43,000 microg/g.dm and Mg with 920 and 1,100 microg/g dm were most abundant. Next, within median values range from approximately 100 to 500 microg/g dm were such as Ca, Fe and Al, and in descending order they followed by Rb (100-400 microg/g dm); V, Na, Zn (50-200 microg/g dm); Cu, Mn (10-50 microg/g dm); Cd (10-20 microg/g dm); Se (5 microg/g dm); Ba (<1-3); Cr, Ag, Pb, Sr (<1-2 microg/g dm); Cs, Co, Hg (<1-1 microg/g dm); Ga (<0.5), Sb, Mo and Tl (<0.1 microg/g dm).

  4. Isolation and characterization of agar-digesting Vibrio species from the rotten thallus of Gracilariopsis heteroclada Zhang et Xia.

    PubMed

    Martinez, Joval N; Padilla, Philip Ian P

    2016-08-01

    Gracilariopsis heteroclada Zhang et Xia (Gracilariaceae, Rhodophyta) is one of the most studied marine seaweeds due to its economic importance. This has been cultivated extensively on commercial scale in the Philippines and other Asian countries. However, sustainable production of G. heteroclada in the Philippines could not be maximized due to the occurrence of rotten thallus disease. Thus, isolation and characterization of agar-digesting bacteria from the rotten thalli of G. heteroclada was conducted. A total of seven representative bacterial isolates were randomly selected based on their ability to digest agar as evidenced by the formation of depressions around the bacterial colonies on nutrient agar plates supplemented with 1.5% NaCl and liquefaction of agar. Gram-staining and biochemical characterization revealed that isolates tested were gram-negative rods and taxonomically identified as Vibrio parahaemolyticus (86-99.5%) and Vibrio alginolyticus (94.2-97.7%), respectively. It is yet to be confirmed whether these agar-digesting vibrios are involved in the induction and development of rotten thallus disease in G. heteroclada in concomitance with other opportunistic bacterial pathogens coupled with adverse environmental conditions.

  5. Performance of chromID Clostridium difficile agar compared with BBL C. difficile selective agar for detection of C. difficile in stool specimens.

    PubMed

    Han, Sang Bong; Chang, Jiyoung; Shin, Sang Hyun; Park, Kang Gyun; Lee, Gun Dong; Park, Yong Gyu; Park, Yeon-Joon

    2014-09-01

    We evaluated the performance of a new chromogenic medium for detection of Clostridium difficile, chromID C. difficile agar (CDIF; bioMérieux, France), by comparison with BBL C. difficile Selective Agar (CDSA; Becton Dickinson and Company, USA). After heat pre-treatment (80℃, 5 min), 185 diarrheal stool samples were inoculated onto the two media types and incubated anaerobically for 24 hr and 48 hr for CDIF and for 48 hr and 72 hr for CDSA. All typical colonies on each medium were examined by Gram staining, and the gram-positive rods confirmed to contain the tpi gene by PCR were identified as C. difficile. C. difficile was recovered from 36 samples by using a combination of the two media. The sensitivity with CDIF 48 hr was highest (100%) and was significantly higher than that with CDIF 24 hr (58.3%; P<0.001), because samples with a low burden of C. difficile tended to require prolonged incubation up to 48 hr (P<0.001). The specificity of CDIF 24 hr and CDIF 48 hr (99.3% and 90.6%, respectively) was significantly higher than that of CDSA 48 hr and CDSA 72 hr (72.5% and 67.1%, respectively; P<0.001). CDIF was effective for detecting C. difficile in heat-pretreated stool specimens, thus reducing unnecessary testing for toxin production in non-C. difficile isolates and turnaround time.

  6. Evaluation of thallium acetate-citrate medium for isolation of enterococci.

    PubMed

    Bulich, A A; Hartman, P A

    1969-11-01

    Thallous acetate-citrate (TAC) agar, a selective medium for isolating enterococci from frozen foods, was evaluated. Two types of bacteria, micrococci and group N streptococci, were responsible for erroneously high enterococcus counts on TAC agar. Selectivity of the medium was improved by the addition of 0.01% sodium azide.

  7. Effect of water potential on sclerotial production by Sclerotinia sclerotiorum in a culture medium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sclerotinia sclerotiorum causes Sclerotinia blight on peanut. Potato dextrose agar medium was prepared and adjusted to various water potentials (-0.4 to -3.4 MPa) using NaCl. Petri plates (9-cm dia) each containing 15 ml of medium were inoculated with a 4-mm agar plug of S. sclerotiorum. Plates w...

  8. Differentiation of Candida dubliniensis from Candida albicans on rosemary extract agar and oregano extract agar.

    PubMed

    de Loreto, Erico Silva; Pozzatti, Patrícia; Alves Scheid, Liliane; Santurio, Deise; Morais Santurio, Janio; Alves, Sydney Hartz

    2008-01-01

    Candida dubliniensis is a recently described pathogenic species which shares many phenotypic features with Candida albicans and therefore, may be misidentified in microbiological laboratories. Because molecular methods can be onerous and unfeasible in routine mycological laboratories with restricted budgets such as those in developing countries, phenotypic techniques have been encouraged in the development of differential media for the presumptive identification of these species. We examined the colony morphology and chlamydospore production of 30 C. dubliniensis isolates and 100 C. albicans isolates on two new proposed media: rosemary (Rosmarinus officinalis) extract agar (REA) and oregano (Origanum vulgare) extract agar (OEA). These substrates are traditionally used as spices and medicinal herbs. In both of these media, all C. dubliniensis isolates (100%) showed rough colonies with peripheral hyphal fringes and abundant chlamydospores after 24 to 48 hr of incubation at 25 degrees C. In contrast, under the same conditions, all isolates of C. albicans (100%) showed smooth colonies without hyphal fringes or chlamydospores. In conclusion, REA and OEA offer a simple, rapid, and inexpensive screening media for the differentiation of C. albicans and C. dubliniensis.

  9. Development and evaluation of a selective and differential medium for the primary isolation of Peptostreptococcus micros.

    PubMed

    Turng, B F; Guthmiller, J M; Minah, G E; Falkler, W A

    1996-10-01

    Peptostreptococcus micros, an anaerobic gram-positive coccus, has been associated with periodontal and endodontic lesions, including those refractory to treatment, as well as many human polymicrobial infections in other body locations. A selective and differential medium for the primary isolation of P. micros was developed and evaluated. Columbia CNA agar, a selective medium for gram-positive cocci, was supplemented with glutathione and lead acetate (P. micros medium: PMM). P. micros has a characteristic of rapidly utilizing the reduced form of glutathione to form hydrogen sulfide, which reacts with lead acetate producing a black precipitate in the medium. When grown on PMM, P. micros can be easily identified by its typical colonial morphology and the presence of a black precipitate directly under the colony. PMM was compared for the growth of P. micros with phenylethyl alcohol agar (PEA) and Columbia base medium (CBM) with 80 strains of P. micros and 30 strains of other gram-positive cocci. All P. micros isolates tested grew and showed the typical morphology of P. micros on PMM. Using colony counts on CBM as controls, there was an average 81.8% recovery in the number of P. micros colonies on PMM, in contrast to an average 6.1% recovery on PEA. Subgingival plaque and tongue samples from 12 adult periodontitis and 6 early-onset periodontitis patients were cultured onto PMM for the isolation of P. micros. P. micros was isolated on PMM and identified biochemically and enzymatically from both adult periodontitis and early-onset periodontitis patients with higher percentages isolated from the diseased periodontal pockets of adult periodontitis patients; furthermore, this is the first isolation of P. micros from tongue samples taken from periodontally diseased patients. This medium in cultural studies will further our understanding and assist future investigations of P. micros involved in disease processes.

  10. Inhibition of Aspergillus flavus on agar media and brown rice cereal bars using cold atmospheric plasma treatment.

    PubMed

    Suhem, Kitiya; Matan, Narumol; Nisoa, Mudtorlep; Matan, Nirundorn

    2013-02-01

    This study aimed to optimize the operating parameters of cold atmospheric plasma treatment to inhibit the growth of Aspergillus flavus on agar media and brown rice cereal bars. The effects of argon plasma jet treatment on the growth of A. flavus on malt extract agar (MEA) at powers of 20 W and 40 W with exposure times at 5, 15 and 25 min were studied using response surface methodology (RSM) with a central composite face-centered (CCF) design. Multiple regression analysis indicated that plasma treatment at 40 W for 25 min is most effective for inhibiting growth of A. flavus on the agar medium. On brown rice cereal bars, plasma powered at 40 W for 20 min was capable of giving protection against A. flavus growth for up to 20 days under storage conditions of 25°C and 100% RH. These results demonstrated the potential of cold atmospheric plasma jet treatment to control mold growth on various food products.

  11. Evaluation of the Granada agar plate for detection of vaginal and rectal group B streptococci in pregnant women.

    PubMed

    Gil, E G; Rodríguez, M C; Bartolomé, R; Berjano, B; Cabero, L; Andreu, A

    1999-08-01

    Granada medium was evaluated for the detection of group B streptococci (GBS) in vaginal and rectal swabs compared with selective Columbia blood agar and selective Lim broth. From May 1996 to March 1998, 702 pregnant women (35 to 37 weeks of gestation) participated in this three-phase study; 103 (14.7%) of these women carried GBS. In the first phase of the experiment (n = 273 women), vaginorectal specimens were collected on the same swab; the sensitivities of Granada tube, selective Columbia blood agar, and Lim broth were 31.4, 94.3, and 74.3%, respectively. In the second and third phases (n = 429 women), vaginal and rectal specimens were collected separately; the sensitivities of Granada plate, selective Columbia blood agar, and Lim broth (subcultured at 4 h on selective Columbia agar in the second phase and at 18 to 24 h in Granada plate in the third phase) were 91.1, 83.9, and 75%, respectively, in the second phase and 88.5, 90.4, and 63.5%, respectively, in the third phase. There were no statistically significant differences in GBS recovery between the Granada agar plate and selective Columbia blood agar, but the Granada plate provided a clear advantage; the characteristic red-orange colonies produced overnight by GBS can be identified by the naked eye and is so specific that further identification is unnecessary. The use of the Granada tube and Lim broth did not result in increased isolation of GBS. In conclusion, the Granada agar plate is highly sensitive for detecting GBS in vaginal and rectal swabs from pregnant women and can provide results in 18 to 24 h.

  12. Evaluation of the Granada Agar Plate for Detection of Vaginal and Rectal Group B Streptococci in Pregnant Women

    PubMed Central

    Gil, E. García; Rodríguez, M. C.; Bartolomé, R.; Berjano, B.; Cabero, L.; Andreu, A.

    1999-01-01

    Granada medium was evaluated for the detection of group B streptococci (GBS) in vaginal and rectal swabs compared with selective Columbia blood agar and selective Lim broth. From May 1996 to March 1998, 702 pregnant women (35 to 37 weeks of gestation) participated in this three-phase study; 103 (14.7%) of these women carried GBS. In the first phase of the experiment (n = 273 women), vaginorectal specimens were collected on the same swab; the sensitivities of Granada tube, selective Columbia blood agar, and Lim broth were 31.4, 94.3, and 74.3%, respectively. In the second and third phases (n = 429 women), vaginal and rectal specimens were collected separately; the sensitivities of Granada plate, selective Columbia blood agar, and Lim broth (subcultured at 4 h on selective Columbia agar in the second phase and at 18 to 24 h in Granada plate in the third phase) were 91.1, 83.9, and 75%, respectively, in the second phase and 88.5, 90.4, and 63.5%, respectively, in the third phase. There were no statistically significant differences in GBS recovery between the Granada agar plate and selective Columbia blood agar, but the Granada plate provided a clear advantage; the characteristic red-orange colonies produced overnight by GBS can be identified by the naked eye and is so specific that further identification is unnecessary. The use of the Granada tube and Lim broth did not result in increased isolation of GBS. In conclusion, the Granada agar plate is highly sensitive for detecting GBS in vaginal and rectal swabs from pregnant women and can provide results in 18 to 24 h. PMID:10405415

  13. Evaluation of brilliance CRE agar for the detection of carbapenem-resistant gram-negative bacteria.

    PubMed

    Bracco, Silvia; Migliavacca, Roberta; Pini, Beatrice; Corbo, Nicoletta; Nucleo, Elisabetta; Brigante, Gioconda; Piazza, Aurora; Micheletti, Piero; Luzzaro, Francesco

    2013-04-01

    The aim of this work was to evaluate the performance of the new chromogenic medium BrillianceTM CREAgar (Thermo Fisher Scientific) for determining the limit of detection of carbapenem-resistant enterobacteria (CRE). A total of 70 clinical isolates were studied. Of these, 30 were well-characterized CRE, including Klebsiella pneumoniae strains producing KPC-, VIM-, and OXA-type enzymes, VIM-positive Enterobacter cloacae and Escherichia coli, NDM-positive E. coli, and enterobacterial isolates characterized by porin loss associated with ESBL production or AmpC hyperproduction. Ten carbapenem-resistant non-fermentative isolates were also included as well as 30 carbapenem-susceptible isolates. Carbapenem-resistant strains were inoculated at three different concentrations onto Brilliance CRE Agar (from 1.5x101 CFU/ml up to 1.5x104 CFU/ml) whereas carbapenem-susceptible isolates were inoculated at a concentration of 1.5x102 CFU/ml. The medium sustained the growth of carbapenem-resistant isolates, showing detection limits from 1.5x101 CFU/ml (in 31/40 cases) to 1.5x104 CFU/ml. No growth was observed with carbapenem-sensitive control strains. Our results indicate that the Brilliance CRE Agar allows the growth of carbapenem-resistant isolates with low detection limits and could represent a useful screening medium for both enterobacteria and non-fermentative Gram-negative strains resistant to carbapenems.

  14. Effect of water structure on gelation of agar in glycerol solutions and phase diagram of agar organogels.

    PubMed

    Boral, Shilpi; Bohidar, H B

    2012-06-21

    A comprehensive study of hydration of polyanionic agar molecules in its solution and gel phase in glycerol-water binary solvent is reported. Raman spectroscopy results predict differential water structure arrangement for glycerol-water binary solvent, 0.02% (w/v) agar in glycerol solution and 0.3% (w/v) agar organogel. The 3200 cm(-1) Raman band pertaining to ice-like structure of water was found to increase in gel phase alike in glycerol-water solvent while it decreased in agar solutions with increase in glycerol concentration. In contrast, the partially structured water corresponding to the component 3310 cm(-1) of Raman spectra increased in agar solution, and decreased in gel phase similar to glycerol-water solvent case. We have explained these observations based on a simple model where the available oxygen to hydrogen atom ratio in a given solvent-polymer system uniquely defines hydration in solution and gel phases. The gelation concentration was found to increase from 0.18 (for water) to 0.22% (w/v) (50% v/v glycerol solution) as the glycerol concentration was raised. Correspondingly, the gelation temperature, T(g), showed a decline from 40 to 20 °C, and the gel melting temperature, T(m), revealed a reduction from 81 to 65 °C in the same glycerol concentration regime. Two distinctive features are evident here: (i) presence of glycerol as a cosolvent does not favor the gelation of agar as compared to water and (ii) agar organogels are softer than their hydrogels. A unique 3D phase diagram for the agar organogel is proposed. Circular dichroism data confirmed that the agar molecules retained their biological activity in these solvents. Thus, it is shown that thermo-mechanical properties of these organogels could be systematically tuned and adapted as per application requirement.

  15. Accumulation of dibenzocyclooctadiene lignans in agar cultures and in stationary and agitated liquid cultures of Schisandra chinensis (Turcz.) Baill.

    PubMed

    Szopa, Agnieszka; Kokotkiewicz, Adam; Marzec-Wróblewska, Urszula; Bucinski, Adam; Luczkiewicz, Maria; Ekiert, Halina

    2016-05-01

    Schisandra chinensis plant in vitro cultures were maintained on Murashige and Skoog (MS) medium supplemented with 3 mg/l 6-benzyladenine (BA) and 1 mg/l 1-naphthaleneacetic acid (NAA) in an agar system and also in two different liquid systems: stationary and agitated. Liquid cultures were grown in batch (30 and 60 days) and fed-batch modes. In the methanolic extracts from lyophilized biomasses and in the media, quantification of fourteen dibenzocyclooctadiene lignans identified based on co-chromatography with authentic standards using high-performance liquid chromatography with diode array detection (HPLC-DAD) and/or liquid chromatography with diode array detection and electrospray ionization mass spectrometry (LC-DAD-ESI-MS) methods. For comparison purposes, phytochemical analyses were performed of lignans in the leaves and fruits of the parent plant. The main lignans detected in the biomass extracts from all the tested systems were schisandrin (max. 65.62 mg/100 g dry weight (DW)), angeloyl-/tigloylgomisin Q (max. 49.73 mg/100 g DW), deoxyschisandrin (max. 43.65 mg/100 g DW), and gomisin A (max. 34.36 mg/100 g DW). The highest total amounts of lignans in the two tested stationary systems were found in extracts from the biomass harvested after 30 days of batch cultivation: 237.86 mg/100 g DW and 274.65 mg/100 g DW, respectively. In the agitated culture, the total content reached a maximum value of 244.80 mg/100 g DW after 60 days of the fed-batch mode of cultivation. The lignans were not detected in the media. This is the first report which documents the potential usefulness of S. chinensis shoot cultures cultivated in liquid systems for practical purposes.

  16. Development of a selective culture medium for Fusarium moniliforme.

    PubMed

    Castellá, G; Bragulat, M R; Rubiales, M V; Cabañes, F J

    1997-12-01

    Nash and Snyder medium and malachite green agar 2.5 ppm medium, a new selective culture medium designed in our laboratory, were challenged with pure cultures of Fusarium moniliforme strains and two different mixed-conidium suspensions, which included rapidly spreading fungi, for their utility in the isolation and enumeration of F. moniliforme. From the results of this comparative study, malachite green agar 2.5 ppm allowed only the selective growth of F. moniliforme whereas Nash and Snyder medium allowed both the growth of F. moniliforme and other species not belonging to Fusarium spp. The enumeration of F. moniliforme propagules was similar in both culture media.

  17. The Resazurin-Agar Method - a Quick Test to Determine Water Quality

    NASA Astrophysics Data System (ADS)

    Huckfeldt, J.; Westphal, B.; Claußen, L.

    2015-12-01

    Rezasurin has been used as a smart tracer in stream ecosystems to indicate metabolic activity, specifically aerobic respiration by heterotrophic bacteria. Resazurin is a blue compound which is irreversibly reduced to the pink resorufin in the presence of aerobic bacteria. The degree and speed of colour change from blue to pink is a measure of the degree of oxygen consumption and thus an indirect indication of the concentration of aerobic bacteria in a given medium. A high concentration of bacteria in water indicates a bad water quality. In our work a method was developed using resazurin agar plates to find a quick and easy way for testing water quality and comparing concentrations of bacteria in freshwater and seawater samples. The theory was to concentrate bacteria from a defined volume of water sample onto polycarbonate filters (0.2 μm), which are then placed onto the resazurin agar plate. The presence of aerobic bacteria on the filter will reduce the resazurin in the agar and the compound changes its colour. First tests conducted with different dilutions of a pure culture of yoghurt bacteria showed promising results and confirmed the feasibility of the method. In a further assay, we used water samples from different water layers and different temperatures and were also able to observe differences in the concentration of bacteria, depending on these different environmental conditions.The assay was also successfully used with seawater samples, collected from 2 different stations at 3 different depths in the Baltic Sea (salinity=15). The discolouration of the plates showed good correlation with the oxygen concentrations in the water. The resazurin-agar plate method is economical and fast. Several samples could be investigated at the same time without sacrificing the reliability of the results. Thus it is a good pre-screening test for a quantitative evaluation of bacteria in a water sample.

  18. Extracellular matrix (ECM) modulates the EGF-induced migration of liver epithelial cells in serum-free, hormone-supplemented medium.

    PubMed

    Bade, E G; Nitzgen, B

    1985-04-01

    The influence of the extracellular matrix (ECM) glycoproteins collagen IV, laminin (LN), and fibronectin (FN) on the in vitro migration of epithelial cells was studied using the ECM migration track method (4) with preparations immunostained for LN and FN. The locomotion of rat liver epithelial cells stimulated to migrate in serum-free medium by epidermal growth factor (EGF) in the presence of insulin is inhibited by substratum-bound FN. The inhibition is concentration-dependent up to 0.7 microgram of the protein per cm2. Neither LN nor collagen IV decreased the number of migrating cells, indicating that the inhibition is a specific effect of fibronectin. The data also indicate that the FN-mediated inhibition of migration is an additional and not alternative mechanism to the well-established contact inhibition of locomotion (1) which also occurs in liver epithelial cell cultures. The system is being used for a further analysis of the factors that influence migration of normal and neoplastic epithelial cells and the biochemical mechanisms underlying the migration reaction.

  19. Use of agar/glycerol and agar/glycerol/water as a translucent brain simulant for ballistic testing.

    PubMed

    Falland-Cheung, Lisa; Waddell, J Neil; Lazarjan, Milad Soltanipour; Jermy, Mark C; Winter, Taylor; Tong, Darryl; Brunton, Paul A

    2017-01-01

    The suitability of agar/glycerol/water and agar/glycerol mixtures as brain simulants was investigated. Test specimens (n=15) (50x27×37mm) were fabricated for these different mixtures and conditioned to 12°C, 22°C, and 26°C prior to testing. For comparison, fresh deer brain specimens (n=20) were sourced and prepared to the same dimensions as the agar/glycerol(/water) mixtures and conditioned to 12°C and 37°C. High impact tests were carried out with a 0.22-caliber air rifle pellet and a high-speed camera was used to record the projectile as it passed through the specimens, allowing for energy loss and vertical displacement velocity calculation. Although the agar/glycerol/water mixture presented with similar vertical expansion and contraction of the specimens to the warm and cold deer brains, a two-fold decrease of the vertical expansion and contraction was noticed with the agar/glycerol specimens. Also considerably less extrusion of this mixture out of the exit and entry sides after specimen penetration was observed. Of the simulants tested, agar/glycerol/water was the most suitable brain simulant for ballistic testing and impact studies.

  20. Growth of human gastric cancer cells in nude mice is delayed by a ketogenic diet supplemented with omega-3 fatty acids and medium-chain triglycerides

    PubMed Central

    Otto, Christoph; Kaemmerer, Ulrike; Illert, Bertram; Muehling, Bettina; Pfetzer, Nadja; Wittig, Rainer; Voelker, Hans Ullrich; Thiede, Arnulf; Coy, Johannes F

    2008-01-01

    Background Among the most prominent metabolic alterations in cancer cells are the increase in glucose consumption and the conversion of glucose to lactic acid via the reduction of pyruvate even in the presence of oxygen. This phenomenon, known as aerobic glycolysis or the Warburg effect, may provide a rationale for therapeutic strategies that inhibit tumour growth by administration of a ketogenic diet with average protein but low in carbohydrates and high in fat enriched with omega-3 fatty acids and medium-chain triglycerides (MCT). Methods Twenty-four female NMRI nude mice were injected subcutaneously with tumour cells of the gastric adenocarcinoma cell line 23132/87. The animals were then randomly split into two feeding groups and fed either a ketogenic diet (KD group; n = 12) or a standard diet (SD group; n = 12) ad libitum. Experiments were ended upon attainment of the target tumor volume of 600 mm3 to 700 mm3. The two diets were compared based on tumour growth and survival time (interval between tumour cell injection and attainment of target tumour volume). Results The ketogenic diet was well accepted by the KD mice. The tumour growth in the KD group was significantly delayed compared to that in the SD group. Tumours in the KD group reached the target tumour volume at 34.2 ± 8.5 days versus only 23.3 ± 3.9 days in the SD group. After day 20, tumours in the KD group grew faster although the differences in mean tumour growth continued significantly. Importantly, they revealed significantly larger necrotic areas than tumours of the SD group and the areas with vital tumour cells appear to have had fewer vessels than tumours of the SD group. Viable tumour cells in the border zone surrounding the necrotic areas of tumours of both groups exhibited a glycolytic phenotype with expression of glucose transporter-1 and transketolase-like 1 enzyme. Conclusion Application of an unrestricted ketogenic diet enriched with omega-3 fatty acids and MCT delayed tumour growth in

  1. High bovine blastocyst development in a static in vitro production system using SOFaa medium supplemented with sodium citrate and myo-inositol with or without serum-proteins.

    PubMed

    Holm, P; Booth, P J; Schmidt, M H; Greve, T; Callesen, H

    1999-09-01

    We describe a bovine embryo culture system that supports repeatable high development in the presence of serum or BSA as well as under defined conditions in the absence of those components. In the first experiment, embryo development in SOF with amino acids (SOFaa), sodium citrate (SOFaac) and myo-inositol (SOFaaci) and with BSA or polyvinyl alcohol (PVA) was compared with that in a M199 granulosa cell co-culture (M199 co-culture). Subsequently, development and cell numbers of blastocysts cultured under defined conditions in SOFaaci with PVA (SOFaaci-PVA), or under undefined conditions in SOFaaci with 5% cow serum (SOFaaci-CS) or M199 co-culture were compared. The repeatability of culture results in SOFaaci-CS was checked by weekly replicates (n = 30) spread over 11 months. The viability of embryos developed in SOFaaci-PVA was estimated by transfer of morphologically good blastocysts (n = 10) to synchronized recipients. In the second experiment, the effect of omitting CS or BSA from IVM and IVM-IVF on subsequent embryo development in SOFaaci-PVA or in SOFaaci-CS was investigated. Blastocyst development in SOFaa-PVA, SOFaac-PVA, SOFaa-BSA and M199 was 16 +/- 3b, 23 +/- 2ab, 30 +/- 8a and 36 +/- 7a%, respectively (Pab < 0.05). Additional inclusion of myoinositol resulted in 42 +/- 1a% blastocysts in SOFaaci-PVA vs 19 +/- 3b% in SOFaac-PVA, 47 +/- 7a% in SOFaac-BSA, and 36 +/- 7a% in M199 co-culture, respectively (Pab < 0.01). In 30 replicates, the average cleavage and blastocyst rates of oocytes in SOFaaci-CS were 87 +/- 4 and 49 +/- 5%, respectively. Five normal calves were produced after transfer of 10 blastocysts developed in defined culture medium (i.e., SOFaaci-PVA). Defined IVM or IVM-IVF (i.e., in absence of CS and BSA) reduced cleavage rates (83 +/- 3 and 55 +/- 3% vs 90 +/- 1% in presence of CS; P < 0.01). Subsequent embryo development in SOFaaci-CS was not affected in either of these defined conditions. However, cleavage and blastocyst rates under completely

  2. Hyperspectral imaging for detecting pathogens grown on agar plates

    NASA Astrophysics Data System (ADS)

    Yoon, Seung Chul; Lawrence, Kurt C.; Siragusa, Gregory R.; Line, John E.; Park, Bosoon; Windham, William R.

    2007-09-01

    This paper is concerned with the development of a hyperspectral imaging technique for detecting and identifying one of the most common foodborne pathogens, Campylobacter. Direct plating using agars is an effective tool for laboratory tests and analyses of microorganisms. The morphology (size, growth pattern, color, etc.) of colonies grown on agar plates has been widely used to tentatively differentiate organisms. However, it is sometimes difficult to differentiate target organisms like Campylobacters from other contaminants grown together on the same agar plates. A hyperspectral imaging system operating at the visible and near infrared (VNIR) spectral region from 400 nm to 900 nm was set up to measure spectral signatures of 17 different Campylobacter and non-Campylobacter subspecies. Protocols for culturing, imaging samples and for calibrating measured data were developed. The VNIR spectral library of all 17 organisms commonly encountered in poultry was established from calibrated hyperspectral images. A classification algorithm was developed to locate and identify Campylobacters, non-Campylobacter contaminants, and background agars with 99.29% accuracy. This research has a potential to be expanded to detect other pathogens grown on agar media.

  3. Fly agaric (Amanita muscaria) poisoning, case report and review.

    PubMed

    Satora, Leszek; Pach, Dorota; Butryn, Beata; Hydzik, Piotr; Balicka-Slusarczyk, Barbara

    2005-06-01

    Gathering and eating mushrooms and other plants containing psychoactive substances has become increasingly popular among young people experimenting with drugs. Dried fly agaric Amanita muscaria fruiting bodies were eaten by five young persons (18-21 years of age) at a party in order to evoke hallucinations. Visual and auditory hallucinations occurred in four of them, whereas a 18-year-old girl lost consciousness. The following morning, she went to the Clinic of Toxicology. Due to the fact that not all the active substances present in the fly agaric have been identified, and some of them have an effect after a period of latency, the patient was admitted for several days of observation during which check-up examinations were performed. After four days without any problems, she was discharged. The poisoning regressed with no organ complications. The remaining persons who had eaten the fly agaric were free from any complaints.

  4. Developmental competence and embryo quality of small oocytes from pre-pubertal goats cultured in IVM medium supplemented with low level of hormones, insulin-transferrin-selenium and ascorbic acid.

    PubMed

    Hammami, S; Morató, R; Romaguera, R; Roura, M; Catalá, M G; Paramio, M T; Mogas, T; Izquierdo, D

    2013-04-01

    The aim of this study was to test the effect of insulin-transferrin-selenium (ITS) and L-ascorbic acid (AA) supplementation and the hormonal level during in vitro maturation (IVM) of small oocytes from pre-pubertal goat on the blastocyst yield and quality. Concretely, we used four maturation media: conventional IVM medium (CM), growth medium (GM: CM+ITS+AA and low level of hormones), modified CM (mCM: CM with low level of hormones) and modified GM (mGM: CM+ITS+AA and normal level of hormones). Cumulus-oocyte complexes (COCs) were classified into two categories according to oocyte diameter: <125 μm and ≥ 125 μm. Large oocytes were matured 24 h in CM (Treatment A). Small oocytes were matured randomly in six experimental groups: Treatment B: 24 h in CM; Treatment C: 12 h in GM and 12 h in CM; Treatment D: 24 h in mGM; Treatment E: 12 h in mGM and 12 h in CM; Treatment F: 12 h in mCM and 12 h in CM; and Treatment G: 12 h in GM and 12 h in mGM. After IVM, oocytes were fertilized and cultured for 8 days. The blastocyst quality was assessed by the survival following vitrification/warming and the mean cell number. When different maturation media were combined, the blastocyst rate did not improve. The large oocytes produced the highest blastocysts yield. However, the culture of small oocytes in GM (53.3%) enhanced the post-warming survival of blastocysts compared to large oocytes matured in CM (35.7%). In conclusion, IVM of pre-pubertal goat small oocytes in GM would be useful to improve the quality of in vitro-produced blastocysts.

  5. Method for Measuring Changes in Surface Tension on Agar

    PubMed Central

    Weisberg, David S.; Dworkin, Martin

    1983-01-01

    The surface tension of agar surfaces was determined by measuring the contact angles formed by drops of various hydrophobic liquids on the surface and then calculating the composite surface free energy function by solving a series of simultaneous equations derived from these data. This method was used to measure the change in the surface tension of agar produced by the addition of various concentrations of albumin. The resulting curve was typical of the effect of increasing concentrations of surfactants on surface tension. The method was compared with other methods of determining surface tension of solids, and it was concluded that the technique used here provided the most reliable results. PMID:16346273

  6. STUDIES ON THE USE OF AMPICILLIN-DEXTRIN AGAR ASAS AEROMONAS RECOVERY MEDIUM

    EPA Science Inventory

    The Contaminant Candidate List (CCL) includes the unregulated chemical and microbiological contaminants the EPA has identified as possibly posing a significant public risk to consumers if present in drinking water (1). There are three bacterial species listed in the CCL (Aeromon...

  7. How do microorganisms influence trace element uptake by plants? Screening in an agar model rhizosphere.

    NASA Astrophysics Data System (ADS)

    Marchetti, M.; Robinson, B. H.; Evangelou, M. W. H.; Vachey, A.; Schwitzguebel, J. P.; Bernier-Latmani, R.; Schulin, R.

    2009-04-01

    sterile, transparent plastic boxes, whose lid was equipped with a filter allowing gas exchanges without contamination by external microorganisms. The seed surface was sterilised and the plants grew one week in agar before their rhizosphere was inoculated with LB broth containing a pure bacterial strain or agar plugs colonized by fungal hyphae. We tested 14 strains, with 5 replicates per treatment and a control where the system was inoculated with sterile LB broth. The plants grew for 2 weeks in a climate chamber and their shoots were analysed for their TEs by ICP-OES. Samples of agar and roots were collected to confirm microbial colonization of the rhizosphere, respectively sterile conditions in the control treatments. Concerning the method development, the plants grew without visible toxicity in all the boxes, and the analysis of root and agar samples indicated that the controls were sterile and the strains inoculated were growing along the roots. More than 90% of the TE and nutrients added to the system were in the liquid fraction of the agar medium, thus available for root uptake. The screening showed that the microorganisms in general decreased TE uptake by wheat and sunflower, although some of them had an opposite effect on the plants. However, with the same plant species, the microorganisms had a consistent effect on all TE tested, i.e. a given single strain caused the same effect (increase or decrease of TE uptake) on all TE tested. In sunflower, 3 microorganisms (Paenibacillus polymyxa, Pythium ultimum and Rhizoctonia solani) decreased Cu and Zn uptake by 50% compared to the control treatment. These three species are common soil microorganisms. All three are known to exude auxin, a phytohormone. This hormone can modify root morphology and physiology and thus may affect TE uptake by plants. R. solani and P. ultimum are root pathogens. Their effect was opposite to what we expected. If roots are damaged, TE should have flooded into the plant and accumulate in the

  8. 21 CFR 866.4600 - Ouchterlony agar plate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ouchterlony agar plate. 866.4600 Section 866.4600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunology Laboratory Equipment and Reagents §...

  9. 21 CFR 866.4600 - Ouchterlony agar plate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ouchterlony agar plate. 866.4600 Section 866.4600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunology Laboratory Equipment and Reagents §...

  10. 21 CFR 866.4600 - Ouchterlony agar plate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ouchterlony agar plate. 866.4600 Section 866.4600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunology Laboratory Equipment and Reagents §...

  11. 21 CFR 866.4600 - Ouchterlony agar plate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ouchterlony agar plate. 866.4600 Section 866.4600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunology Laboratory Equipment and Reagents §...

  12. 21 CFR 866.4600 - Ouchterlony agar plate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ouchterlony agar plate. 866.4600 Section 866.4600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunology Laboratory Equipment and Reagents §...

  13. Improving agar electrospinnability with choline-based deep eutectic solvents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One percent agar (% wt) was dissolved in the deep eutectic solvent (DES), (2-hydroxyethyl) trimethylammonium chloride/urea at a 1:2 molar ratio, and successfully electrospun into nanofibers. An existing electrospinning set-up, operated at 50 deg C, was adapted for use with an ethanol bath to collect...

  14. [Modification of the lysine-iron agar (author's transl)].

    PubMed

    Wauters, G

    1975-12-01

    The addition of L-phenylalanine to the lysine-iron agar described by Edwards and Fife ]1] allows a more valuable screening of the Proteus group based on its deamination properties. Some minor modifications of the indicator and thiosulfate content lead to improve and earlier recording of the results.

  15. Sports Supplements

    MedlinePlus

    ... for Parents for Kids for Teens Teens Home Body Mind Sexual Health Food & Fitness Diseases & Conditions Infections Q& ... Sports Supplements? How Some Common Supplements Affect the Body Will Supplements ... improving your sports performance is probably on your mind. Lots of people wonder if taking sports supplements ...

  16. Broth and agar hop-gradient plates used to evaluate the beer-spoilage potential of Lactobacillus and Pediococcus isolates.

    PubMed

    Haakensen, M; Schubert, A; Ziola, B

    2009-03-15

    Identification of the beer-spoilage Lactobacillus and Pediococcus bacteria has largely taken two approaches; identification of spoilage-associated genes or identification of specific species of bacteria regardless of ability to grow in beer. The problem with these two approaches is that they are either overly inclusive (i.e., detect all bacteria of a given species regardless of spoilage potential) or overly selective (i.e., rely upon individual, putative spoilage-associated genes). Our goal was to design a method to assess the ability of Lactobacillus and Pediococcus to spoil beer that is independent of speciation or genetic background. In searching for a method by which to differentiate between beer-spoilage bacteria and bacteria that cannot grow in beer, we explored the ability of lactobacilli and pediococci isolates to grow in the presence of varying concentrations of hop-compounds and ethanol in broth medium versus on agar medium. The best method for differentiating between bacteria that can grow in beer and bacteria that do not pose a threat as beer-spoilage organisms was found to be a hop-gradient agar plate containing ethanol. This hop-gradient agar plate technique provides a rapid and simple solution to the dilemma of assessing the ability of Lactobacillus and Pediococcus isolates to grow in beer, and provides new insights into the different strategies used by these bacteria to survive under the stringent conditions of beer.

  17. Thermal-induced ageing of agar solutions: impact on the structural and mechanical properties of agar gels

    NASA Astrophysics Data System (ADS)

    Mao, Bosi; Bentaleb, Ahmed; Louerat, Frédéric; Divoux, Thibaut; Snabre, Patrick

    Numerous hydrogels are prepared by cooling down to ambient temperature, aqueous polymer solutions brought to a boil. Although the incubation time of the polymer solution at such a high temperature could be used as a tuning parameter, its impact on the subsequent gelation has been poorly investigated. Here we study the effect of prolonged heating at 80°C on a 1.5% wt solution of agar, a natural polysaccharide. The incubation time is varied from a few hours up to five days. We show that the agar sol. continuously degrades as the result of both the hydrolysis and the intermolecular oxidation of the polymer chains. Furthermore, electronic microscopy and X-ray diffraction experiments reveal that gels formed from older agar sols display an increasingly coarser microstructure composed of micron-sized aggregated pieces of polysaccharides, in contrast with the fibrous-like structure of gels made from fresh sols. Along with structural changes prolonged incubation time leads to weaker gels of lower shear elastic modulus. Finally, macro-indentation experiments coupled to direct visualization show that increasing the incubation time of the agar sol. decreases the yield strain of the gel by a factor of three, while the rupture scenario turns continuously from brittle to ductile-like. Acknowledging funding from BioMérieux & CNRS.

  18. Performance of Chromogenic Candida agar and CHROMagar Candida in recovery and presumptive identification of monofungal and polyfungal vaginal isolates.

    PubMed

    Ozcan, Kadri; Ilkit, Macit; Ates, Aylin; Turac-Bicer, Aygul; Demirhindi, Hakan

    2010-02-01

    Chromogenic Candida agar (OCCA) is a novel medium facilitating isolation and identification of Candida albicans, C. tropicalis, and C. krusei, as well as indicating polyfungal population in clinical samples. We compare the performance of OCCA, to CHROMagar Candida (CAC) and Sabouraud chloramphenicol agar (SCA). Vaginal swab samples from 392 women were simultaneously inoculated onto three study media. A total of 161 (41.1%) were found to be positive for fungi of which 140 (87%) were monofungal, and 21 (13%) polyfungal. One-hundred and fifty-seven samples (97.5%) were positive on CAC, 156 (96.9%) on OCCA, 148 (91.9%) on SCA and 144 (89.4%) samples were positive on all three media. The yeasts were identified by conventional methods including germ tube test, microscopic morphology on cornmeal-Tween 80 agar, and the commercial API 20C AUX. The 182 isolates were C. albicans (n = 104), C. glabrata (n = 51), C. krusei (n = 7), C. tropicalis (n = 5), C. famata (n = 3), C. kefyr (n = 3), C. zeylanoides (n = 3), C. colliculosa (n = 2), and other species of Candida (n = 4). Among the 21 polyfungal populations, 20 (95.2%) were detected in OCCA, 14 (66.7%) in CAC, and 13 (61.9%) in CAC and OCCA (P <0.05). Most polyfungal populations (47.6%) yielded C. albicans + C. glabrata. The efficiency of both chromogenic media for C. albicans was >or=92.9% at 72 h. OCCA is more efficient and reliable for rapidly identifying C. albicans and polyfungal populations than CAC. However, CAC is more efficient for identifying C. krusei and C. tropicalis. A chromogenic agar with a higher isolation rate of yeasts and better detection of polyfungal populations than SCA, is suggested as a medium of first choice when available.

  19. Comparison of dosimetry gels prepared by agar and bovine gelatine

    NASA Astrophysics Data System (ADS)

    Sağsöz, M. E.; Korkut, Ö.; Alemdar, N.; Aktaş, S.; Çalı, E. B.; Kantarcı, M.

    2016-04-01

    Gel dosimeters are unique materials capable of showing three dimensional (3D) dose distributions of therapeutic or diagnostic exposures. Fricke gel dosimeters can be considered as chemical dosimeters that rely on a radiation-induced chemical reaction. Dose distribution of Fricke solutions containing Fe+2 ions determines the transformation of acidic, oxygen saturated Fe+2 ions to Fe+3 ions by the ionizing radiation in aqueous solutions. In this study we produced two different types of gel dosimeters using agar and bovine gelatin with similar fabrication methods. We compared the magnetic resonance (MR) T1 imaging responses of these two gel dosimeters to acquire a dose dependency of MR intensities. In conclusion agar gel dosimeters found to be produced easily and more consistent.

  20. A modified agar plate method for detection of Strongyloides stercoralis.

    PubMed

    Koga, K; Kasuya, S; Khamboonruang, C; Sukhavat, K; Ieda, M; Takatsuka, N; Kita, K; Ohtomo, H

    1991-10-01

    The agar plate method is a new technique with high detection rates for coprological diagnosis of human strongyloidiasis. This report details modifications of the technique and establishes a standardized procedure. We recommend that all plates should be carefully observed using a microscope because macroscopic observation can lead to false negative results. It is also advisable to pour formalin solution directly into microscopically positive dishes to collect worms by sedimentation. This procedure enables one to observe worms otherwise hidden. Sealing dishes with adhesive tape prevents larvae from crawling out of the dishes, eliminating any possibility in the reduction of detection rates, and greatly improves the safety conditions for the technician performing the procedure. We consider the agar plate method to be superior to the filter paper method in detecting Strongyloides, and we believe that it will eventually become the technique of choice.

  1. Agar-degrading bacteria isolated from Antarctic macroalgae.

    PubMed

    Alvarado, Roxana; Leiva, Sergio

    2017-03-10

    This study describes the taxonomic diversity of pigmented, agar-degrading bacteria isolated from the surface of macroalgae collected in King George Island, Antarctica. A total of 30 pigmented, agarolytic bacteria were isolated from the surface of the Antarctic macroalgae Adenocystis utricularis, Monostroma hariotii, Iridaea cordata, and Pantoneura plocamioides. Based on the 16S rRNA data, the agarolytic isolates were affiliated to the genera Algibacter, Arthrobacter, Brachybacterium, Cellulophaga, Citricoccus, Labedella, Microbacterium, Micrococcus, Salinibacterium, Sanguibacter, and Zobellia. Isolates phylogenetically related to Cellulophaga algicola showed the highest agarase activity in culture supernatants when tested at 4 and 37 °C. This is the first investigation of pigmented agar-degrading bacteria, members of microbial communities associated with Antarctic macroalgae, and the results suggest that they represent a potential source of cold-adapted agarases of possible biotechnological interest.

  2. Modeling development of inhibition zones in an agar diffusion bioassay.

    PubMed

    Chandrasekar, Vaishnavi; Knabel, Stephen J; Anantheswaran, Ramaswamy C

    2015-09-01

    A two-temperature agar diffusion bioassay is commonly used to quantify the concentration of nisin using Micrococcus luteus as the indicator microorganism. A finite element computational model based on Fick's second law of diffusion was used to predict the radius of the inhibition zone in this diffusion bioassay. The model developed was used to calculate nisin concentration profiles as a function of time and position within the agar. The minimum inhibitory concentration (MIC) of nisin against M. luteus was determined experimentally. The critical time (T c) for growth of M. luteus within the agar diffusion bioassay was experimentally determined using incubation studies with nisin. The radius of the inhibition zone was predicted from the computational model as the location where the predicted nisin concentration at T c was equal to MIC. The MIC was experimentally determined to be 0.156 μg mL(-1), and T c was determined to be 7 h. Good agreement (R (2) = 0.984) was obtained between model-predicted and experimentally determined inhibition zone radii.

  3. Improved medium for antimicrobial susceptibility testing of Haemophilus influenzae.

    PubMed Central

    Jorgensen, J H; Redding, J S; Maher, L A; Howell, A W

    1987-01-01

    The need for complex growth media has complicated routine susceptibility testing of Haemophilus influenzae because of antagonism of certain antimicrobial agents by the medium or because of difficulties in interpretation of growth endpoints. Haemophilus test medium (HTM) is a simple, transparent medium for broth- or agar-based tests with H. influenzae. HTM incorporates Mueller-Hinton medium with additions of 15 micrograms of hematin per ml, 15 micrograms of NAD per ml, and 5 mg of yeast extract per ml as growth-promoting additives. Agar or broth microdilution MICs of 10 antimicrobial agents for a collection of 179 H. influenzae isolates determined by using HTM compared favorably with MICs determined by the conventional agar or broth dilution methods recommended by the National Committee for Clinical Laboratory Standards. Disk diffusion tests performed with HTM allowed accurate categorization of susceptible and resistant strains and were easier to interpret than tests performed with Mueller-Hinton chocolate agar. A particular advantage of HTM was the reliability of broth- or agar-based test results with trimethoprim-sulfamethoxazole. The results of the study suggest modification of current National Committee for Clinical Laboratory Standards MIC-interpretive criteria for H. influenzae with amoxicillin-clavulanate, chloramphenicol, and trimethoprim-sulfamethoxazole. Error rate-bounded analysis of MICs and disk diffusion zone sizes also suggest modified zone-interpretive criteria for ampicillin, amoxicillin-clavulanate, chloramphenicol, and tetracycline with HTM or conventional media. Interpretive zone sizes are newly proposed for cefaclor and rifampin disk diffusion tests. PMID:3500965

  4. Development of a differential medium for bile salt hydrolase-active Lactobacillus spp.

    PubMed Central

    Dashkevicz, M P; Feighner, S D

    1989-01-01

    An agar plate assay was developed to detect bile salt hydrolase activity in lactobacilli. On Lactobacillus-selective MRS or Rogosa SL medium supplemented with taurodeoxycholic, taurocholic, or taurochenodeoxycholic acids, bile salt hydrolysis was manifested at two intensities: (i) the formation of precipitate halos around colonies or (ii) the formation of opaque granular white colonies. Sixty-six lactobacilli were tested for bile salt hydrolase activity by both the plate assay and a sensitive radiochemical assay. No false-positive or false-negative results were detected by the plate assay. Based on results of experiments with Eubacterium lentum and Bacteroides species, the plate assay was dependent on two factors: (i) the presence of bile salt hydrolytic activity and (ii) the ability of the organism to sufficiently acidify the medium to protonate free bile acids. The availability of a differential medium for determination of bile salt hydrolase activity will provide a rapid method for determining shifts in a specific functional activity of intestinal Lactobacillus species and provide a rapid screening capability for identifying bile salt hydrolase-deficient mutants. The latter application should allow bile salt hydrolase activity to be used as a marker enzyme in genetic experiments. Images PMID:2705765

  5. Electrospinning of agar/PVA aqueous solutions and its relation with rheological properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this work, we report the successful fabrication of agar-based nanofibers by an electrospinning technique using water as the solvent media. A tubeless spinneret was attached inside the electrospinning chamber, operated at 50 deg C, to avoid agar gelation. Pure agar solution 1% (w/w) showed inadequ...

  6. Development of an eco-friendly agar extraction technique from the red seaweed Gracilaria lemaneiformis.

    PubMed

    Li, Haiyan; Yu, Xingju; Jin, Yan; Zhang, Wei; Liu, Yuanling

    2008-05-01

    The red seaweed, Gracilaria lemaneiformis growing as an aquaculture bioremediator along the coasts of Liaodong Peninsula, China, was investigated for the agar production. An eco-friendly method called agar photobleaching extraction process was developed for the benefit of workers' health and safety of the environment. The native agar (NA), alkali-modified agar (AA), chemical-bleached agar (CA) and photobleached agar (PA), which were extracted using different processes, were evaluated for their physical and chemical properties. The PA showed most desirable performances in terms of gel strength, gelling temperature, sulfate content and 3,6-anhydro-l-galactose content. Among the different processed agars, PA gel strength was 1913 g/cm2, the highest among the different processed agars, which increased 8.6% on the basis of the AA. Further we applied this new technique to extract agars from Gracilaria asiatica, and similar results were obtained with that of G. lemaneiformis. This indicates that the agar photobleaching extraction process is a feasible method for Gracilaria species and has a potential application. During the whole agar photobleaching extraction process the pigment content of G. lemaneiformis declined gradually and the TOC concentration in photobleaching solution increased along with the increase in the irradiation time. The mechanism of agar photobleaching could be elucidated by the photolysis theory.

  7. Multicenter clinical evaluation of VRESelect agar for identification of vancomycin-resistant Enterococcus faecalis and Enterococcus faecium.

    PubMed

    Anderson, Neil W; Buchan, Blake W; Young, Carol L; Newton, Duane W; Brenke, Connie; Lapsley, Linda; Granato, Paul A; Ledeboer, Nathan A

    2013-08-01

    A chromogenic medium for identification of vancomycin-resistant Enterococcus faecalis and Enterococcus faecium, VRESelect, was compared to bile esculin azide agar with 6 μg/ml vancomycin (BEAV) for the isolation of vancomycin-resistant enterococci (VRE) from stool specimens. At 24 to 28 h, VRESelect demonstrated 98.7% (confidence interval [CI], 96.1 to 99.7%) sensitivity and 99.0% (CI, 98.0 to 99.6%) specificity versus 85.1% (CI, 79.8 to 89.5%) and 90.1% (CI, 79.8 to 89.5%) sensitivity and specificity, respectively, for BEAV.

  8. Development of blood-yolk-polymyxin B-trimethoprim agar for the enumeration of Bacillus cereus in various foods.

    PubMed

    Kim, Dong-Hyeon; Kim, Hyunsook; Chon, Jung-Whan; Moon, Jin-San; Song, Kwang-Young; Seo, Kun-Ho

    2013-07-15

    Blood-yolk-polymyxin B-trimethoprim agar (BYPTA) was developed by the addition of egg yolk, laked horse blood, sodium pyruvate, polymyxin B, and trimethoprim, and compared with mannitol-yolk-polymyxin B agar (MYPA) for the isolation and enumeration of Bacillus cereus (B. cereus) in pure culture and various food samples. In pure culture, there was no statistical difference (p>0.05) between the recoverability and sensitivity of MYPA and BYPTA, whereas BYPTA exhibited higher specificity (p<0.05). To evaluate BYPTA agar with food samples, B. cereus was experimentally spiked into six types of foods, triangle kimbab, sandwich, misugaru, Saengsik, red pepper powder, and soybean paste. No statistical difference was observed in recoverability (p>0.05) between MYPA and BYPTA in all tested foods, whereas BYPTA exhibited higher selectivity than MYPA, especially in foods with high background microflora, such as Saengsik, red pepper powder, and soybean paste. The newly developed selective medium BYPTA could be a useful enumeration tool to assess the level of B. cereus in foods, particularly with high background microflora.

  9. Development of a selective enterococcus medium based on manganese ion deficiency, sodium azide, and alkaline pH.

    PubMed

    Efthymiou, C J; Joseph, S W

    1974-09-01

    Rogosa broth, without its salt supplement and dissolved in deionized water, was adapted for the selective isolation and enumeration of enterococci. This medium supported good growth of enterococci, but it suppressed growth of other lactic acid bacteria. The sensitivity and specificity of the medium were tested after addition of various increasing concentrations of NaN(3) against known strains of enterococci and other bacteria. Many strains of Streptococcus faecium showed low azide tolerance; optimal growth was obtained at a concentration of 0.01% NaN(3), which totally or partially inhibited unrelated species of lactic acid bacteria. The selectivity of the medium was further increased by pH adjustment to 9.6. Carbonate and Tween 80 were added to overcome partial inhibition of enterococcal growth by the new combination of selective conditions. The final medium was evaluated in agar form in isolations from human and animal feces, polluted water, meat, and dairy products. Counts were obtained after 16 to 17 h of incubation at 37 C. The isolates satisfactorily conformed to the group characteristics of enterococci.

  10. Development of a Selective Enterococcus Medium Based on Manganese Ion Deficiency, Sodium Azide, and Alkaline pH

    PubMed Central

    Efthymiou, C. J.; Joseph, S. W.

    1974-01-01

    Rogosa broth, without its salt supplement and dissolved in deionized water, was adapted for the selective isolation and enumeration of enterococci. This medium supported good growth of enterococci, but it suppressed growth of other lactic acid bacteria. The sensitivity and specificity of the medium were tested after addition of various increasing concentrations of NaN3 against known strains of enterococci and other bacteria. Many strains of Streptococcus faecium showed low azide tolerance; optimal growth was obtained at a concentration of 0.01% NaN3, which totally or partially inhibited unrelated species of lactic acid bacteria. The selectivity of the medium was further increased by pH adjustment to 9.6. Carbonate and Tween 80 were added to overcome partial inhibition of enterococcal growth by the new combination of selective conditions. The final medium was evaluated in agar form in isolations from human and animal feces, polluted water, meat, and dairy products. Counts were obtained after 16 to 17 h of incubation at 37 C. The isolates satisfactorily conformed to the group characteristics of enterococci. Images PMID:4214072

  11. Evaluation of Urea-motility-indole medium for recognition and differentiation of Salmonella and Shigella species in stool cultures.

    PubMed

    Rosa Fraile, M; Vega Aleman, D; Fernandez Gutierrez, C

    1980-09-01

    A semisolid urea-motility-indole medium designed for detection in Enterobacteriaceae of urease activity, motility, and indole production in one tube was prepared and evaluated. The formulation of the medium was similar to that of Christensen urea agar, but the agar concentration was 0.2%, and 1% tryptone was added. Results with 687 strains of Enterobacteriaceae were the same as those obtained with standard test media (98% overall agreement). The urea-motility-indole medium was also used in combination with Kligler iron agar for the recognition and differentiation of Salmonella and Shigella species from colonies picked from plating media in fecal cultures. This combination was compared with the combination of Kligler iron agar and lysine iron agar with 507 strains of non-lactose-fermenting Enterobacteriaceae. Although both combinations enabled the presumptive recognition and differentiation of Salmonella and Shigella species, an analysis of data indicated that the combination of Kligler iron agar and urea-motility-indole medium performed better than the combination of Kligler iron agar and lysine iron agar in detecting Salmonella and Shigella species.

  12. The Polymyxin Ceftazidime Oxford Medium as an alternative selective and differential medium for isolation of Listeria monocytogenes from raw or unpasteurized food.

    PubMed

    Martínez-Gonzáles, N E; Martínez-Chávez, L; Martínez-Cárdenas, C; Cabrera-Díaz, E; Castillo, A

    2014-04-01

    The Polymyxin Ceftazidime Oxford Medium (PCOM) was developed to recover Listeria monocytogenes from raw or unpasteurized foods. It contains esculin-ferric ammonium citrate as indicator system for Listeria growth, and ceftazidime and polymyxin B as selective agents, which are available in several Latin American countries. Comparison of PCOM, Modified Oxford Medium (MOX) and Tryptic Soy agar with 0.6% yeast extract (TSAYE) indicated that both selective media were equally effective at recovering four individual strains of L. monocytogenes (Scott A, V7, California and broccoli), and a mixture of these strains (LMM) (P > 0.05). The ability of PCOM, MOX, TSAYE and TSAYE supplemented with 4% NaCl to recover heat, acid and freeze-damaged LMM was similar for all media (P > 0.05). The PCOM proved to be effective at isolating colonies of LMM from inoculated raw beef chunks, unpasteurized orange juice, cabbage, and Mexican-style cheese by direct plating and by the US Department of Agriculture's Food Safety and Inspection Service enrichment method. Differentiation of L. monocytogenes colonies was easier on PCOM than on MOX for foods with high levels of background microbiota. Based on the evaluations performed on foods naturally contaminated with L. monocytogenes, PCOM was a more economical alternative than MOX for selective and differential isolation of Listeria from raw or unpasteurized foods.

  13. Assessment of the suitability of mannitol salt agar for growing bovine-associated coagulase-negative staphylococci and its use under field conditions.

    PubMed

    De Visscher, A; Haesebrouck, F; Piepers, S; Vanderhaeghen, W; Supré, K; Leroy, F; Van Coillie, E; De Vliegher, S

    2013-10-01

    This study aimed at testing the applicability of mannitol salt agar (MSA), a medium generally used in human medicine for differentiating Staphylococcus aureus from coagulase-negative staphylococci (CNS), for culturing bovine-associated CNS species. All test isolates from a comprehensive collection of well-identified CNS species, including both reference strains and field isolates, were able to grow. Subsequently, bulk milk samples and teat apex swabs were used to examine the capability of MSA for yielding CNS under field conditions. Sixty-nine and 47 phenotypically different colonies were retrieved from bulk milk and teat apices, respectively. The majority of isolates from teat apices were staphylococci, whereas in bulk milk, staphylococci formed a minority. After 24h of growth, recovery of separate colonies of CNS was much more convenient on MSA compared to a non-selective blood agar. The results of this study indicate that MSA is a suitable medium for both growth and recovery of bovine-associated CNS.

  14. A differential medium for the isolation and rapid identification of a plant soft rot pathogen, Erwinia chrysanthemi.

    PubMed

    Lee, Yung-An; Yu, Cheng-Pin

    2006-02-01

    A medium was developed for the isolation and differentiation of Erwinia chrysanthemi from other Erwinia spp. based on the production of blue-pigmented indigoidine. The medium, named NGM, consists of nutrient agar supplemented with 1% glycerol, that induces pigment production, and 2 mM MnCl2*4H2O, that further enhances color development. More than fifty E. chrysanthemi strains from six different plant hosts were tested. All tested strains of E. chrysanthemi grew well on the NGM medium, developing dark brownish to blue colonies easily distinguishable from other Erwinia spp. The results indicate that pigment production on the NGM medium is a very stable property and can be used as a phenotypic property to differentiate E. chrysanthemi from other Erwinia spp. In addition, a specific oligonucleotide primer set was designed for the detection of indC, which is involved in indigoidine biosynthesis. All E. chrysanthemi strains tested contained indC as determined by PCR amplification. No amplification was observed with other Erwinia spp. Thus, pigment production of E. chrysanthemi on the NGM medium is consistent with the existence of indC. The NGM medium was used to isolate and identify the causal agent of soft rot lesions of diseased Phalaenopsis orchids from three orchid cultivation areas in Taiwan. The causal agents of Phalaenopsis soft rot were all identified as E. chrysanthemi. The results indicate that the NGM medium is efficient in isolation and identification of E. chrysanthemi from plants with soft rot symptoms and can also be used for epidemiological studies.

  15. Dietary Supplements

    MedlinePlus

    ... other products. They can come as pills, capsules, powders, drinks, and energy bars. Supplements do not have to go through the testing that drugs do. Some supplements can play an important role in health. For example, calcium and vitamin D are important for keeping bones ...

  16. Characterization of Leptospiral Chemoreceptors Using a Microscopic Agar Drop Assay.

    PubMed

    Affroze, Samia; Islam, Md Shafiqul; Takabe, Kyosuke; Kudo, Seishi; Nakamura, Shuichi

    2016-08-01

    Bacterial chemotaxis is induced by sensing chemical stimuli via chemoreceptors embedded in the cytoplasmic membrane, enabling the cells to migrate toward nutrients or away from toxins. The chemoreceptors of Escherichia coli and Salmonella spp. have been well studied and are functionally classified on the basis of detectable substrates. The spirochete Leptospira possesses more than ten chemoreceptors and shows attractive or repellent responses against some sugars, amino acids, and fatty acids. However, the roles of these chemoreceptors have not been investigated. In this study, we conducted a chemotaxis assay called microscopic agar drop assay in combination with competition experiments, determining whether two kinds of attractants are recognized by the same type of chemoreceptor in the saprophytic Leptospira strain, Leptospira biflexa. Analyzing the competition effect observed between several pairs of chemicals, we found that L. biflexa senses sugars via chemoreceptors different from those that sense amino acids and fatty acids.

  17. Normal force controlled rheology applied to agar gelation

    NASA Astrophysics Data System (ADS)

    Mao, Bosi; Divoux, Thibaut; Snabre, Patrick

    2016-05-01

    A wide range of thermoreversible gels are prepared by cooling down to ambient temperature hot aqueous polymer solutions. During the sol-gel transition, such materials may experience a volume contraction which is traditionally overlooked as rheological measurements are usually performed in geometries of constant volume. In this article, we revisit the formation of 1.5\\% wt. agar gels through a series of benchmark rheological experiments performed with a plate-plate geometry. We demonstrate on that particular gel of polysaccharides that the contraction associated with the sol/gel transition cannot be neglected. Indeed, imposing a constant gap width during the gelation results in the strain hardening of the sample, as evidenced by the large negative normal force that develops. Such hardening leads to the slow drift in time of the gel elastic modulus $G'$ towards ever larger values, and thus to an erroneous estimate of $G'$. As an alternative, we show that imposing a constant normal force equals to zero during the gelation, instead of a constant gap width, suppresses the hardening as the decrease of the gap compensates for the sample contraction. Using normal force controlled rheology, we then investigate the impact of thermal history on 1.5\\% wt. agar gels. We show that neither the value of the cooling rate, nor the introduction of a constant temperature stage during the cooling process influence the gel elastic properties. Instead, $G'$ only depends on the terminal temperature reached at the end of the cooling ramp, as confirmed by direct imaging of the gel microstructure by cryoelectron microscopy. The present work offers an extensive review of the technical difficulties associated with the rheology of hydrogels and paves the way for a systematic use of normal force controlled rheology to monitor non-isochoric processes.

  18. Evaluation of BBL CHROMagar orientation medium for detection and presumptive identification of urinary tract pathogens.

    PubMed Central

    Hengstler, K A; Hammann, R; Fahr, A M

    1997-01-01

    The microbiological performance of BBL CHROMagar Orientation medium and CPS ID2 agar was compared to that of Columbia agar with 5% sheep blood and MacConkey agar without crystal violet for the enumeration and presumptive identification of bacteria responsible for urinary tract infections. Of a total of 658 clinical urine specimens, 118 specimens yielded no growth, 402 specimens yielded growth with cell counts of > or = 10(5) CFU/ml, and 138 specimens yielded growth with cell counts of < 10(5) CFU/ml. Of the specimens with cell counts of > or = 10(5) CFU/ml, 163 were pure cultures and 239 were mixed cultures. A total of 266 Escherichia coli organisms were isolated on both chromogenic media, 260 were isolated on blood agar, and 248 were isolated on MacConkey agar. One strain (0.4%) failed to develop the expected pink color on CHROMagar Orientation medium, and 23 strains (8.7%) failed to develop the expected pink color on CPS ID2 agar. Enterococci (CHROMagar Orientation medium, n = 266; CPS ID2 agar, n = 265) produced small blue-green colonies on both chromogenic media. Fifty of the mixed cultures contained enterococci that were detected only on the chromogenic media. The Klebsiella-Enterobacter-Serratia (KES) and the Proteus-Morganella-Providencia (PMP) groups could be identified on both chromogenic media. Of 66 isolates of the KES group, 63 grew with the expected color on CHROMagar Orientation medium and 58 of 64 isolates grew with the expected color on CPS ID2 agar. Other microorganisms required further identification. The use of chromogenic medium formulations offers a time-saving method for the reliable detection, enumeration, and presumptive identification of urinary tract pathogens. One of the greatest advantages of these media is the easy recognition of mixed cultures. PMID:9350731

  19. Comparison of spiral gradient and conventional agar dilution for susceptibility testing of anaerobic bacteria.

    PubMed Central

    Wexler, H M; Molitoris, E; Jashnian, F; Finegold, S M

    1991-01-01

    Antimicrobial susceptibility tests were performed on brucella laked blood agar with 340 isolates and 14 antimicrobial agents by the standard agar dilution technique and the spiral gradient technique in which antibiotic concentrations were established by diffusion from the agar surface. For comparison, spiral gradient MICs were determined by calculating antimicrobial concentrations at growth endpoints and rounding up to the next twofold incremental concentration. The cumulative percentage of strains susceptible at the breakpoint determined from spiral gradient data was within 10%, generally, of the percentage of strains susceptible at the breakpoint determined from agar dilution data. The overall agreement between the two techniques (within one doubling dilution) was 90.6%. The spiral gradient agar dilution technique is a reasonable alternative to the conventional agar dilution technique for susceptibility testing of anaerobic bacteria. Images PMID:1929262

  20. In vitro fermentation and prebiotic potential of novel low molecular weight polysaccharides derived from agar and alginate seaweeds.

    PubMed

    Ramnani, Priya; Chitarrari, Roberto; Tuohy, Kieran; Grant, John; Hotchkiss, Sarah; Philp, Kevin; Campbell, Ross; Gill, Chris; Rowland, Ian

    2012-02-01

    Fermentation properties and prebiotic potential of novel low molecular weight polysaccharides (LMWPs) derived from agar and alginate bearing seaweeds was investigated. Ten LMWPs were supplemented to pH, temperature controlled anaerobic batch cultures inoculated with human feces from three donors, in triplicate. Microbiota changes were monitored using Fluorescent in-situ hybridization and short chain fatty acids, the fermentation end products were analysed using gas chromatography. Of the ten LMWPs tested, Gelidium seaweed CC2253 of molecular weight 64.64 KDa showed a significant increase in bifidobacterial populations from log(10) 8.06 at 0 h to log(10) 8.55 at 24 h (p = 0.018). For total bacterial populations, alginate powder CC2238 produced a significant increase from log(10) 9.01 at 0 h to log(10) 9.58 at 24 h (p = 0.032). No changes were observed in the other bacterial groups tested viz. Bacteroides, Lactobacilli/Enterococci, Eubacterium rectale/Clostridium coccoides and Clostridium histolyticum. The polysaccharides also showed significant increases in total SCFA production, particularly acetic and propionic acids, indicating that they were readily fermented. In conclusion, some LMWPs derived from agar and alginate bearing seaweeds were fermented by gut bacteria and exhibited potential to be used a novel source of prebiotics.

  1. Residual Agar Determination in Bacterial Spores by Electrospray Ionization Mass Spectrometry

    SciTech Connect

    Wahl, Karen L.; Colburn, Heather A.; Wunschel, David S.; Petersen, Catherine E.; Jarman, Kristin H.; Valentine, Nancy B.

    2010-02-15

    Presented here is an analytical method to detect residual agar from a bacterial spore sample as an indication of culturing on an agar plate. This method is based on the resolubilization of agar polysaccharide from a bacterial spore sample, enzymatic digestion, followed by electrospray ionization tandem mass spectrometry (ESI-MSn) analysis for detection of a specific agar fragment ion. A range of Bacillus species and strains were selected to demonstrate the effectiveness of this approach. The characteristic agar fragment ion was detected in the spores grown on agar that were washed from 1 to 5 times, irradiated or non-irradiated and not in the spores grown in broth. A sample containing approximately 108 spores is currently needed for confident detection of residual agar from culture on agar plates in the presence of bacterial spores with a limit of detection of approximately 1 ppm agar spiked into a broth-grown spore sample. The results of a proficiency test with 42 blinded samples are presented demonstrating the utility of this method with no false positives and only 3 false negatives for samples that were below the detection level of the method as documented.

  2. Biochemical differentiation of the Enterobacteriaceae with the aid of lysine-iron-agar.

    PubMed

    Johnson, J G; Kunz, L J; Barron, W; Ewing, W H

    1966-03-01

    A procedure is described for identifying members of the family Enterobacteriaceae isolated from clinical specimens. The methods are based on primary differentiation of the various groups of bacteria by the use of Kligler Iron Agar and lysine-iron-agar. For identification of Salmonella, Shigella, and Arizona group organisms from stools, Triple Sugar Iron Agar and lysine-iron-agar are employed. The usefulness of this schema for diagnostic bacteriology laboratories is discussed. It is not intended to replace methods used in reference or research laboratories.

  3. Nepali Supplements.

    ERIC Educational Resources Information Center

    Peace Corps, Washington, DC.

    This volume is intended as a supplement to Nepali language instruction. It contains songs, numerals, dialogues in Devanagari script, a Nepali-English, English-Nepali glossary, and an English-Nepali surveyor technical glossary. (AM)

  4. Calcium supplements

    MedlinePlus

    ... TYPES OF CALCIUM SUPPLEMENTS Forms of calcium include: Calcium carbonate: Over-the-counter (OTC) antacid products, such as Tums and Rolaids, contain calcium carbonate. These sources of calcium do not cost much. ...

  5. A quasi-universal medium to break the aerobic/anaerobic bacterial culture dichotomy in clinical microbiology.

    PubMed

    Dione, N; Khelaifia, S; La Scola, B; Lagier, J C; Raoult, D

    2016-01-01

    In the mid-19th century, the dichotomy between aerobic and anaerobic bacteria was introduced. Nevertheless, the aerobic growth of strictly anaerobic bacterial species such as Ruminococcus gnavus and Fusobacterium necrophorum, in a culture medium containing antioxidants, was recently demonstrated. We tested aerobically the culture of 623 bacterial strains from 276 bacterial species including 82 strictly anaerobic, 154 facultative anaerobic, 31 aerobic and nine microaerophilic bacterial species as well as ten fungi. The basic culture medium was based on Schaedler agar supplemented with 1 g/L ascorbic acid and 0.1 g/L glutathione (R-medium). We successively optimized this media, adding 0.4 g/L uric acid, using separate autoclaving of the component, or adding haemin 0.1 g/L or α-ketoglutarate 2 g/L. In the basic medium, 237 bacterial species and ten fungal species grew but with no growth of 36 bacterial species, including 22 strict anaerobes. Adding uric acid allowed the growth of 14 further species including eight strict anaerobes, while separate autoclaving allowed the growth of all tested bacterial strains. To extend its potential use for fastidious bacteria, we added haemin for Haemophilus influenzae, Haemophilus parainfluenzae and Eikenella corrodens and α-ketoglutarate for Legionella pneumophila. This medium allowed the growth of all tested strains with the exception of Mycobacterium tuberculosis and Mycobacterium bovis. Testing primoculture and more fastidious species will constitute the main work to be done, but R-medium coupled with a rapid identification method (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry) will facilitate the anaerobic culture in clinical microbiology laboratories.

  6. Comparison of isolation of Haemophilus vaginalis (Corynebacterium vaginale) from peptone-starch-dextrose agar and Columbia colistin-nalidoxic acid agar.

    PubMed Central

    Golberg, R L; Washington JA, I I

    1976-01-01

    A total of 447 cervical or vaginal specimens were inoculated in parallel onto peptone-starch-dextrose (PSD) and Columbia colistin (10 mg/ml)-nalidixic acid (15 mug/ml) (CNA) agar and were incubated for 48 h at 35 degrees C in an atmosphere with 2 to 10% CO2. One hundred (22.4%) of the cultures were positive for Haemophilus vaginalis. Forty-eight of the isolates were recovered from both PSD and Columbia CNA agar, five from PSD only, and 47 from Columbia CNA agar only (P less than 0.001). On Columbia CNA agar, 76 of the isolates were detected after 24 h of incubation, and the remainder were detected within 4 days of incubation. PMID:1085777

  7. Creatine supplementation.

    PubMed

    Hall, Matthew; Trojian, Thomas H

    2013-01-01

    Creatine monohydrate is a dietary supplement that increases muscle performance in short-duration, high-intensity resistance exercises, which rely on the phosphocreatine shuttle for adenosine triphosphate. The effective dosing for creatine supplementation includes loading with 0.3 g·kg·d for 5 to 7 days, followed by maintenance dosing at 0.03 g·kg·d most commonly for 4 to 6 wk. However loading doses are not necessary to increase the intramuscular stores of creatine. Creatine monohydrate is the most studied; other forms such as creatine ethyl ester have not shown added benefits. Creatine is a relatively safe supplement with few adverse effects reported. The most common adverse effect is transient water retention in the early stages of supplementation. When combined with other supplements or taken at higher than recommended doses for several months, there have been cases of liver and renal complications with creatine. Further studies are needed to evaluate the remote and potential future adverse effects from prolonged creatine supplementation.

  8. Effect of transport enrichment medium, transport time, and growth medium on the detection of Campylobacter fetus subsp. venerealis.

    PubMed

    Monke, Holly J; Love, Brenda C; Wittum, Thomas E; Monke, Donald R; Byrum, Beverly A

    2002-01-01

    The combination of medium and growth conditions, including transport enrichment medium (TEM), transport time, TEM incubation time, and growth medium, that best support Campylobacter fetus subsp. venerealis while inhibiting contaminants was studied. The 3 TEMs evaluated, Weybridge, Cary-Blair, and 0.85% saline solution, were inoculated with preputial smegma spiked with C. fetus subsp. venerealis and held in the laboratory for 4 or 24 hours before inoculation onto growth medium. The effect of overnight incubation at 37 C of the TEM was also evaluated. Median scores of C. fetus subsp. venerealis growth and microbial contaminant inhibition were compared within TEM, transport time, overnight incubation, and growth medium groups using the Mann-Whitney U-test and the Kruskal-Wallis test. The proportion of samples with any growth or contamination within each group was also compared using the chi-square test. Results suggest that the growth of C. fetus subsp. venerealis was influenced by 3 of the 4 criteria evaluated. Weybridge TEM more effectively maintained the organism than did either Cary-Blair or 0.85% saline solution (P < 0.001). Transport time of 4 hours rather than 24 hours (P < 0.001) and avoiding overnight incubation of TEM at 37 C (P < 0.001) were associated with improved growth. Significant differences were not identified among growth media; however, Skirrow Campylobacter agar appeared to yield slightly better growth than did either blood agar or Greenbriar Plus agar. Contaminant growth was also influenced by 3 of the 4 variables. Weybridge TEM inhibited contaminant growth more effectively than did either Cary-Blair or 0.85% saline solution (P < 0.001). Transport time was not associated with contaminant growth. Eliminating overnight incubation of TEM reduced contamination (P < 0.01). Skirrow agar was preferred to both blood agar and Greenbriar Plus agar for suppression of contaminants on solid medium (P < 0.001). These results suggest that the detection of C

  9. A selective chromogenic agar that distinguishes Bacillus anthracis from Bacillus cereus and Bacillus thuringiensis.

    PubMed

    Juergensmeyer, Margaret A; Gingras, Bruce A; Restaino, Lawrence; Frampton, Elon W

    2006-08-01

    A selective and differential plating medium, R & F anthracis chromogenic agar (ACA), has been developed for isolating and identifying presumptive colonies of Bacillus anthracis. ACA contains the chromogenic substrate 5-bromo-4-chloro-3-indoxyl-choline phosphate that upon hydrolysis yields teal (blue green) colonies indicating the presence of phosphatidylcholine-specific phospholipase C (PC-PLC) activity. Among seven Bacillus species tested on ACA, only members of the Bacillus cereus group (B. anthracis, B. cereus, and B. thuringiensis) produced teal colonies (PC-PLC positive) having cream rings. Examination of colony morphology in 18 pure culture strains of B. anthracis (15 ATCC strains plus AMES-1-RIID, ANR-1, and AMED-RIID), with one exception, required 48 h at 35 to 37 degrees C for significant color production, whereas only 24 h was required for B. cereus and B. thuringiensis. This differential rate of PC-PLC synthesis in B. anthracis (due to the truncated plcR gene and PlcR regulator in B. anthracis) allowed for the rapid differentiation on ACA of presumptive colonies of B. anthracis from B. cereus and B. thuringiensis in both pure and mixed cultures. Effective recovery of B. anthracis from a variety of matrices having both high (soil and sewage) and low microbial backgrounds (cloth, paper, and blood) spiked with B. anthracis ANR-1 spores suggests the probable utility of ACA plating for B. anthracis recovery in a diversity of applications.

  10. NAS agar is more suitable than McKay agar for primary culture of Streptococcus milleri group (SMG) fastidious bacteria, S. intermedius in particular.

    PubMed

    Raclavsky, Vladislav; Novotny, Radko; Stary, Lubomir; Navratilova, Lucie; Zatloukal, Jaromir; Jakubec, Petr; Zapalka, Martin; Kopriva, Frantisek; Kolek, Vitezslav

    2017-01-01

    Streptococcus milleri group (SMG) is a group of three streptococcal species (S. anginosus, intermedius and constellatus) that act as opportunist pathogens, among others in cystic fibrosis. Due to their fastidious character, they are both difficult to cultivate and to differentiate from less pathogenic streptococcal species, therefore being most probably underdiagnosed. Semi-selective McKay agar and NAS agar were developed to facilitate SMG recovery from clinical samples; however, direct comparison of recovery rates has not been published yet. We tested the performance of both media on 123 patient samples and demonstrated general superiority of NAS agar for SMG recovery during primary cultivation convincingly. This observation was also confirmed by quantitative drop tests during subculture. Despite the undisputed overall superiority of NAS agar over McKay agar, a smaller fraction of strains grew better on McKay agar. Inter-strain differences were the most probable explanation. Therefore, when economic conditions are not limiting and maximum recovery rate is desirable, both plates are advised to be used in parallel for primary cultivation of clinical samples.

  11. Optimization of modified Middlebrook 7H11 agar for isolation of Mycobacterium bovis from raw milk cheese.

    PubMed

    Forgrave, R; Donaghy, J A; Fisher, A; Rowe, M T

    2014-10-01

    Reports have highlighted the absence of contemporary peer reviewed publications pertaining to Mycobacterium bovis culture from raw milk and cheese. By replicating traditional methods, cheese-making methodology and equipment were devised to produce Cheddar (n = 6) and Caerphilly (n = 3) artificially contaminated with M. bovis (three genotypes) under stringent laboratory-containment guidelines for handling hazardous microbiological material. Middlebrook 7H11, modified for M. bovis isolation, was assessed for capacity to enumerate M. bovis despite changing cheese microflora and prolonged M. bovis exposure to the cheese matrix using maturing cheese test portions (n = 63; up to 16 weeks). Malachite green (MG) containing media isolated M. bovis at significantly (P < 0·05) lower levels than unmodified Middlebrook 7H11 agar despite MG being a common adjunct of Middlebrook 7H11 agar modified for M. bovis growth. Subsequently, a selective MG-free Middlebrook 7H11 agar modified using haemolysed red cells and calf serum was demonstrated as the best performing (P < 0·05) medium for recovery of M. bovis from typical UK cheese types, Cheddar and Caerphilly. Significance and impact of the study: Following increased M. bovis infection of UK cattle, the risk posed to consumers from consumption of unpasteurized milk and dairy products has changed. Furthermore, published methods for the culture and molecular detection of M. bovis in raw milk products are limited. Cheese-making protocols and M. bovis culture media reported here provide tools for further investigation of M. bovis survival during all stages of cheese manufacture and could inform future assessment of the risk to consumers from M. bovis contamination of unpasteurized dairy products.

  12. NEW MEDIUM FOR THE SIMULTANEOUS DETECTION OF TOTAL COLIFORMS AND ESCHERICHIA COLI IN WATER (PUBLISHED ERRATUM APPEARS IN APP ENVIRON MICROBIOL 1993 DEC;59(12):4378)

    EPA Science Inventory

    A new membrane filter agar medium (MI agar) containing a chromogen, indoxyl-beta-D-glucuronide, and a fluorogen, 4-methylumbelliferyl-beta-D-galactopyranoside, was developed to simultaneously detect and enumerate Escherichia coli and total coliforms (TC) in water samples on the b...

  13. Electrospinning of agar/PVA aqueous solutions and its relation with rheological properties.

    PubMed

    Sousa, Ana M M; Souza, Hiléia K S; Uknalis, Joseph; Liu, Shih-Chuan; Gonçalves, Maria P; Liu, LinShu

    2015-01-22

    In this work, we report the successful fabrication of agar-based nanofibers by electrospinning technique, using water as solvent media. A tubeless spinneret was attached inside the electrospinning chamber, operating at 50°C, to avoid agar gelation. Agar pure solution (1 wt%) showed inadequate spinnability regardless of the used electrospinning conditions. The addition of a co-blending polymer such as PVA (10 wt% starting solution) improved the solutions viscoelasticity and hence, the solutions spinnability. Agar/PVA solutions were prepared with different mass ratios (100/0, 50/50, 40/60, 30/70, 20/80 and 0/100) and electrospun at various sets of electrospinning conditions. Best nanofibers were obtained with 30/70 and 20/80 agar/PVA blends while samples with higher agar contents (50/50 and 40/60 agar/PVA) were harder to process and led to discontinuous fibrous mats. This first set of encouraging results can open a new window of opportunities for agar-based biomaterials in the form of nanofibers.

  14. Characteristics of thermoplastic sugar palm Starch/Agar blend: Thermal, tensile, and physical properties.

    PubMed

    Jumaidin, R; Sapuan, S M; Jawaid, M; Ishak, M R; Sahari, J

    2016-08-01

    The aim of this work is to study the behavior of biodegradable sugar palm starch (SPS) based thermoplastic containing agar in the range of 10-40wt%. The thermoplastics were melt-mixed and then hot pressed at 140°C for 10min. SEM investigation showed good miscibility between SPS and agar. FT-IR analysis confirmed that SPS and agar were compatible and inter-molecular hydrogen bonds existed between them. Incorporation of agar increased the thermoplastic starch tensile properties (Young's modulus and tensile strength). The thermal stability and moisture uptake increased with increasing agar content. The present work shows that starch-based thermoplastics with 30wt% agar content have the highest tensile strength. Higher content of agar (40wt%) resulted to more rough cleavage fracture and slight decrease in the tensile strength. In conclusion, the addition of agar improved the thermal and tensile properties of thermoplastic SPS which widened the potential application of this eco-friendly material. The most promising applications for this eco-friendly material are short-life products such as packaging, container, tray, etc.

  15. Adsorptive removal of methylene blue by agar: effects of NaCl and ethanol

    PubMed Central

    2012-01-01

    Adsorption of methylene blue (MB) on agar was investigated as a function of temperature (308-328 K), different concentrations of NaCl and HCl and various weight percentages of binary mixtures of ethanol with water. It was observed that the maximum experimental adsorption capacity, qm, exp, in water is up to 50 mg g-1 and decreases with increase in weight percentage of ethanol and NaCl and HCl concentration compared to that of water. Analysis of data using ARIAN model showed that MB adsorbs as monomer and dimer on the surface of agar. Binding constants of MB to agar were calculated using the Temkin isotherm. The process is exothermic in water and other solutions. The mean adsorption energy (E) value indicated binding of MB to agar is chemical adsorption. Kinetics of this interaction obeys from the pseudo-second-order model and diffusion of the MB molecules into the agar is the main rate-controlling step. PMID:22339759

  16. Growth of purified astrocytes in a chemically defined medium

    SciTech Connect

    Morrison, R.S.; De Vellis, J.

    1981-11-01

    Astrocytes purified from primary cultures of neonatal rat cerebrum can not be grown in a synthetic medium supplemented with putrescine, prostaglandin F/sub 2//sub ..cap alpha../, insulin, fibroblast growth factor, and hydrocortisone. These five supplements have a marked synergistic effect on growth when used in combination but have little effect when used individually. Astrocytes grown in the defined medium exhibit dramatic changes in morphological characteristics in comparison to cells grown in serum-free or serum-supplemented medium. In addition, these cells express the astrocyte-specific marker glial fibrillary acidic protein and are estimated by several criteria to be greater than 95% astrocytes.

  17. Continuous degradation of maltose: improvement in stability and catalytic properties of maltase (α-glucosidase) through immobilization using agar-agar gel as a support.

    PubMed

    Nawaz, Muhammad Asif; Karim, Asad; Aman, Afsheen; Marchetti, Roberta; Qader, Shah Ali Ul; Molinaro, Antonio

    2015-04-01

    Maltose degrading enzyme was immobilized within agar-agar support via entrapment method due to its industrial utilization. The maximum immobilization efficiency (82.77%) was achieved using 4.0% agar-agar keeping the diameter of bead up to 3.0 mm. The matrix entrapment showed maximum catalytic activity at pH 7.0 and temperature 65 °C. Substrate saturation kinetics showed that the K m of immobilized enzyme increased from 1.717 to 2.117 mM ml(-1) where as Vmax decreased from 8,411 to 7,450 U ml(-1 )min(-1) as compared to free enzyme. The immobilization significantly increased the stability of maltase against various temperatures and immobilized maltase retain 100% of its original activity after 2 h at 50 °C, whereas the free maltase only showed 60% residual activity under same condition. The reusability of entrapped maltase showed activity up to 12 cycles and retained 50% of activity even after 5th cycle. Storage stability of agar entrapped maltase retain 73% of its initial activity even after 2 months when stored at 30 °C while free enzyme showed only 37% activity at same storage conditions.

  18. Universal growth of microdomains and gelation transition in agar hydrogels.

    PubMed

    Boral, Shilpi; Saxena, Anita; Bohidar, H B

    2008-03-27

    Investigations were carried out on aqueous sols and gels of agar (extracted from red seaweed Gelidiella acerosa) to explore the growth of microdomains en route to gelation. Isothermal frequency sweep studies on gel samples revealed master plots showing power-law dependence of gel elastic modulus, |G*|, on oscillation frequency, omega as |G*| approximately omegan, independent of temperature, with 0.5Tg). The S(q,t) behavior close to the gel transition point (Tg approximately (38+/-3 degrees C determined from rheology) followed a stretched exponential function: S(t)=A exp(-t/ts)beta. The beta factor increased from 0.25 to 1 as the gel temperature approached 25 degrees C from Tg, and relaxation time, ts, showed a peak at T approximately 30 degrees C. The SLS data (in the sol state) suggested the scaling of scattered intensity, Is(q) approximately epsilon(-gamma) (epsilon=(T/Tg-1), T>Tg) with gamma=0.13+/-0.03, and the presence of two distinct domains characterized by a Guinier regime (low q) and a power-law regime (high q). Close to and above Tg (+2 degrees C), IS(q) scaled with q as Is(q) approximately q(-alpha) with alpha=2.2+/-0.2, which decreased to 1.4+/-1 just below Tg (-2 degrees C), implying a coil-helix transition for 0.2% (w/v) and 0.3% (w/v) samples. For a 0.01% sample, alpha=3.5+/-0.5 which

  19. [The two-phase growth medium for sub-culturing of Helicobacter pylori].

    PubMed

    Isaeva, G Sh; Aleshkin, V A; Sel'kova, E P; Gerasimova, M S; Moroz, P I

    2013-06-01

    A. Pylori is a very undemanding microorganism needing the in support of complex of conditions including particular atmosphere, temperature of culturing and composition of growth medium. The two-phase growth medium is recommended to sub-culturing in Petri dishes with diameter of 90 mm. The growth medium consists of chocolate agar with addition of Schedler broth and enriched with 10% serum of cattle.

  20. Detection of Agar, by Analysis of Sugar Markers, Associated with Bacillus Anthracis Spores, After Culture

    SciTech Connect

    Wunschel, David S.; Colburn, Heather A.; Fox, Alvin; Fox, Karen F.; Harley, William M.; Wahl, Jon H.; Wahl, Karen L.

    2008-08-01

    Detection of small quantities of agar associated with spores of Bacillus anthracis could provide key information regarding its source or growth characteristics. Agar, widely used in growth of bacteria on solid surfaces, consists primarily of repeating polysaccharide units of 3,6-anhydro-L-galactose (AGal) and galactose (Gal) with sulfated and O-methylated galactoses present as minor constituents. Two variants of the alditol acetate procedure were evaluated for detection of potential agar markers associated with spores. The first method employed a reductive hydrolysis step, to stabilize labile anhydrogalactose, by converting to anhydrogalactitol. The second eliminated the reductive hydrolysis step simplifying the procedure. Anhydrogalactitol, derived from agar, was detected using both derivatization methods followed by gas chromatography-mass spectrometry (GC-MS) analysis. However, challenges with artefactual background (reductive hydrolysis) or marker destruction (hydrolysis) lead to the search for alternative sugar markers. A minor agar component, 6-O-methyl galactose (6-O-M gal), was readily detected in agar-grown but not broth-grown bacteria. Detection was optimized by the use of gas chromatography-tandem mass spectrometry (GC-MS-MS). With appropriate choice of sugar marker and analytical procedure, detection of sugar markers for agar has considerable potential in microbial forensics.

  1. Membrane-assisted culture of fungal mycelium on agar plates for RNA extraction and pharmacological analyses.

    PubMed

    Lange, Mario; Müller, Carolin; Peiter, Edgar

    2014-05-15

    Fungal mycelium grown in liquid culture is easy to harvest for RNA extraction and gene expression analyses, but liquid cultures often develop rather heterogeneously. In contrast, growth of fungal mycelium on agar plates is highly reproducible. However, this biological material cannot be harvested easily for downstream analyses. This article describes a PVDF (polyvinylidene difluoride) membrane-assisted agar plate culture method that enables the harvest of mycelium grown on agar plates. This culture method leads to a strongly reduced variation in gene expression between biological replicates and requires less growth space as compared with liquid cultures.

  2. Comparative evaluation of Strepto B ID chromogenic medium and Granada media for the detection of Group B streptococcus from vaginal samples of pregnant women.

    PubMed

    Tazi, Asmaa; Réglier-Poupet, Hélène; Dautezac, François; Raymond, Josette; Poyart, Claire

    2008-06-01

    Two types of selective media, the chromogenic medium Strepto B ID and two non-chromogenic media Strepto B agar and the Granada medium, were tested and compared to blood agar plates (BAP) for screening of Group B streptococcus vaginal colonization in pregnant women. All tested media were comparable in terms of sensitivity however, their use in routine laboratories may markedly facilitate the rapid detection of GBS in vaginal samples.

  3. Growth characteristics of Bacillus anthracis compared to other Bacillus spp. on the selective nutrient media Anthrax Blood Agar and Cereus Ident Agar.

    PubMed

    Tomaso, Herbert; Bartling, Carsten; Al Dahouk, Sascha; Hagen, Ralf M; Scholz, Holger C; Beyer, Wolfgang; Neubauer, Heinrich

    2006-01-01

    Anthrax Blood Agar (ABA) and Cereus Ident Agar (CEI) were evaluated as selective growth media for the isolation of Bacillus anthracis using 92 B. anthracis and 132 other Bacillus strains from 30 species. The positive predictive values for the identification of B. anthracis on ABA, CEI, and the combination of both were 72%, 71%, and 90%, respectively. Thus, less than 10% of all species were misidentified using both nutrient media. Species which might be misidentified as B. anthracis were B. cereus, B. mycoides, and B. thuringiensis. Particularly, 30% of B. weihenstephanensis strains were misidentified as B. anthracis.

  4. Selective medium for culture of Mycoplasma hyopneumoniae.

    PubMed

    Cook, Beth S; Beddow, Jessica G; Manso-Silván, Lucía; Maglennon, Gareth A; Rycroft, Andrew N

    2016-11-15

    The fastidious porcine respiratory pathogen Mycoplasma hyopneumoniae has proven difficult to culture since it was first isolated in 1965. A reliable solid medium has been particularly challenging. Moreover, clinical and pathological samples often contain the fast-growing M. hyorhinis which contaminates and overgrows M. hyopneumoniae in primary culture. The aim of this study was to optimise the culture medium for recovery of M. hyopneumoniae and to devise a medium for selection of M. hyopneumoniae from clinical samples also containing M. hyorhinis. The solid medium devised by Niels Friis was improved by use of Purified agar and incorporation of DEAE-dextran. Addition of glucose or neutralization of acidity in liquid medium with NaOH did not improve the final yield of viable organisms or alter the timing of peak viability. Analysis of the relative susceptibility of M. hyopneumoniae and M. hyorhinis strains to four antimicrobials showed that M. hyopneumoniae is less susceptible than M. hyorhinis to kanamycin. This was consistent in all UK and Danish strains tested. A concentration of 2μg/ml of kanamycin selectively inhibited the growth of all M. hyorhinis tested, while M. hyopneumoniae was able to grow. This forms the basis of an effective selective culture medium for M. hyopneumoniae.

  5. Novel single-tube agar-based test system for motility enhancement and immunocapture of Escherichia coli O157:H7 by H7 flagellar antigen-specific antibodies.

    PubMed

    Murinda, Shelton E; Nguyen, Lien T; Ivey, Susan J; Almeida, Raul A; Oliver, Stephen P

    2002-12-01

    This paper describes a novel single-tube agar-based technique for motility enhancement and immunoimmobilization of Escherichia coli O157:H7. Motility indole ornithine medium and agar (0.4%, wt/vol) media containing either nutrient broth, tryptone broth, or tryptic soy broth (TSBA) were evaluated for their abilities to enhance bacterial motility. Twenty-six E. coli strains, including 19 O157:H7 strains, 1 O157:H(-) strain, and 6 generic E. coli strains, were evaluated. Test bacteria were stab inoculated in the center of the agar column, and tubes were incubated at 37 degrees C for 18 to 96 h. Nineteen to 24 of the 26 test strains (73.1 to 92.3%) were motile in the different media. TSBA medium performed best and was employed in subsequent studies of motility enhancement and H7 flagellar immunocapture. H7 flagellar antiserum (30 and 60 micro l) mixed with TSBA was placed as a band (1 ml) in the middle of an agar column separating the top (3-ml) and bottom (3-ml) agar layers. The top agar layer was inoculated with the test bacterial strains. The tubes were incubated at 37 degrees C for 12 to 18 h and for 18 to 96 h. The specificity and sensitivity of the H7 flagellar immunocapture tests were 75 and 100%, respectively. The procedure described is simple and sensitive and could be adapted easily for routine use in laboratories that do not have sophisticated equipment and resources for confirming the presence of H7 flagellar antigens. Accurate and rapid identification of H7 flagellar antigen is critical for the complete characterization of E. coli O157:H7, owing to the immense clinical, public health, and economic significance of this food-borne pathogen.

  6. Chiral response of Oryzeae and Paniceae plants in alpha-methylbenzyl-3-p-tolyl urea agar medium.

    PubMed

    Omokawa, Hiroyoshi; Murata, Hiroshi; Kobayashi, Shoko

    2004-01-01

    The results presented here support the hypothesis that plants of the tribe Oryzeae respond enantioselectively and homogeneously to optically active 1-alpha-methylbenzyl-3-p-tolylurea (MBTU) in root growth inhibition, in contrast to Echinochloa species. The Oryzeae plants tested in this study belong to different genera (Oryza, Leersia, Chikusichloa and Zizania), to different species (O sativa, O glaberrima, O alta, O coarctata, O latifolia, O minuta, O rufipogon), to various ecospecies of Oryza (japonica, indica, japonica x indica, javanica) and to different levels of evolution [cultivated rice (O sativa and O glaberrima) and ancestral wild rice species]. In spite of their different phylogenic status and diverse sensitivity, the root growth of all members of the genus Oryza was inhibited more by R-MBTU than by S-MBTU. Zizania palustris, Z latifolia, Leersia oryzoides and Chikusichloa aquatica belonging to the tribe Oryzeae exhibited similar chiral recognition to the Oryza plants, suggesting that Oryzeae have a common chiral recognition mechanism in their response to optically active MBTUs. In contrast, Echinochloa plants (E crus-galli (L) Beauv var crus-galli and E colonum (L) Link), belonging into subfamily Panicoideae tribe Paniceae, responded in a different way, where their root growth was more sensitive to S-MBTU than to the antipodal R-MBTU. A reverse chiral response between the tribe Oryzeae and the genus Echinochloa was clearly indicated in this study. This diverse response may be relevant to Gramineae classification.

  7. A fresh liver agar substrate for rearing small numbers of forensically important blow flies (Diptera: Calliphoridae)

    USGS Publications Warehouse

    Gruner, Susan V.; Slone, Daniel H.

    2014-01-01

    Forensically important calliphorids can be reared on a mixture of beef liver and agar. Small pieces of meat, especially fresh or frozen beef liver, will desiccate in 2–6 h, but this simple-to-make feeding substrate remains moist for at least 12 h at 25 and 30°C without desiccation, even in small (5 g) amounts. We determined the survivorship of small numbers of Chrysomya megacephala (F.) (first-instar larvae to adult eclosion) raised on 5 g of liver agar and fresh beef liver. We found that all larvae raised on 5 g of liver died due to desiccation, but survivorship on 5 g of liver agar was equivalent to that on larger (50 g) pieces of either liver agar or beef liver.

  8. A fresh liver agar substrate for rearing small numbers of forensically important blow flies (Diptera: Calliphoridae).

    PubMed

    Gruner, Susan V; Slone, Daniel H

    2014-05-01

    Forensically important calliphorids can be reared on a mixture of beef liver and agar. Small pieces of meat, especially fresh or frozen beef liver, will desiccate in 2-6 h, but this simple-to-make feeding substrate remains moist for at least 12 h at 25 and 30 degrees C without desiccation, even in small (5 g) amounts. We determined the survivorship of small numbers of Chrysomya megacephala (F.) (first-instar larvae to adult eclosion) raised on 5 g of liver agar and fresh beef liver. We found that all larvae raised on 5 g of liver died due to desiccation, but survivorship on 5 g of liver agar was equivalent to that on larger (50 g) pieces of either liver agar or beef liver.

  9. Proton beam writing of microstructures in Agar gel for patterned cell growth

    NASA Astrophysics Data System (ADS)

    Larisch, Wolfgang; Koal, Torsten; Werner, Ronald; Hohlweg, Marcus; Reinert, Tilo; Butz, Tilman

    2011-10-01

    A rather useful prerequisite for many biological and biophysical studies, e.g., for cell-cell communication or neuronal networks, is confined cell growth on micro-structured surfaces. Solidified Agar layers have smooth surfaces which are electrically neutral and thus inhibit receptor binding and cell adhesion. For the first time, Agar microstructures have been manufactured using proton beam writing (PBW). In the irradiated Agar material the polysaccharides are split into oligosaccharides which can easily be washed off leaving Agar-free areas for cell adhesion. The beam diameter of 1 μm allows the fabrication of compartments accommodating single cells which are connected by micrometer-sized channels. Using the external beam the production process is very fast. Up to 50 Petri dishes can be produced per day which makes this technique very suitable for biological investigations which require large throughputs.

  10. The growth of Paracoccus halodenitrificans in a defined medium

    NASA Technical Reports Server (NTRS)

    Hochstein, L. I.; Tomlinson, G. A.

    1984-01-01

    A synthetic medium, consisting of inorganic salts and any of a number of carbon sources, supported the aerobic growth of Paracoccus halodenitrificans when supplemented with thiamine. The same medium plus a nitrogenous oxide supported anaerobic growth when additionally supplemented with methionine. The observation that vitamin B12 or betaine replaced methionine suggested that P. halodenitrificans had a defect in the cobalamin dependent pathway for methionine biosynthesis, as well as the inability to synthesize betanine when growing anaerobically.

  11. The growth of paracoccus halodenitrificans in a defined medium

    NASA Technical Reports Server (NTRS)

    Hochstein, L. I.; Tomlinson, G. A.

    1983-01-01

    A synthetic medium, consisting of inorganic salts and any of a number of carbon sources, supported the aerobic growth of Paracoccus halodenitrificans when supplemented with thiamine. The same medium plus a nitrogenous oxide supported anaerobic growth when additionally supplemented with methionine. The observation that vitamin B12 or betaine replaced methionine suggested that P. halodenitrificans had a defect in the cobalamin dependent pathway for methionine biosynthesis, as well as the inability to synthesize betaine when growing anaerobically.

  12. Selective Medium for Hydrogen Sulfide Production by Salmonellae

    PubMed Central

    Padron, A. P.; Dockstader, W. B.

    1972-01-01

    Triple Sugar Iron Agar does not reveal hydrogen sulfide production by all Salmonella organisms nor does it permit clear-cut separation of those nonsalmonellae which produce H2S. Numerous media with varied combinations of nutrients, inhibitors, selective agents, pH levels, and metal salts were tested for H2S production of cultures of Salmonella, Citrobacter, Edwardsiella, Arizona, Proteus, Providencia, Klebsiella, and Enterobacter. An agar medium has been devised which promotes growth and H2S production (generally within 6 hr) by Salmonella, Arizona, and Edwardsiella but which inhibits hydrogen sulfide production or growth of all other gram-negative organisms tested (including Citrobacter) or inhibits both. The use of this medium should facilitate the selection and identification of Salmonella. PMID:4557561

  13. Effects of medium concentration on antibody production

    NASA Technical Reports Server (NTRS)

    Williams, J.

    1984-01-01

    Antibody production by two different cell lines was measured as the media were supplemented with varied amounts of glucose and fetal bovine serum. Both cell lines elaborated antidinitrophenyl hapten antibodies. Two basic media were used: RPMI 1640 and Dulbecco's modified Eagle's medium. The production of antibodies was followed from 0 to 180 h and was assayed by radioimmunoassay.

  14. Genome Sequence of the Agar-Degrading Marine Bacterium Alteromonadaceae sp. Strain G7

    PubMed Central

    Kwak, Min-Jung; Song, Ju Yeon; Kim, Byung Kwon; Chi, Won-Jae; Kwon, Soon-Kyeong; Choi, Soobeom; Chang, Yong-Keun

    2012-01-01

    Here, we present the high-quality draft genome sequence of the agar-degrading marine gammaproteobacterium Alteromonadaceae sp. strain G7, which was isolated from coastal seawater to be utilized as a bioresource for production of agar-derived biofuels. The 3.91-Mb genome contains a number of genes encoding algal polysaccharide-degrading enzymes such as agarases and sulfatases. PMID:23209220

  15. Low density, microcellular, dopable, agar/gelatin foams for pulsed power experiments

    SciTech Connect

    McNamara, W.F.; Aubert, J.H.

    1997-04-01

    Low-density, microcellular foams prepared from the natural polymers agar and gelatin have been developed for pulsed-power physics experiments. Numerous experiments were supported with foams having densities at or below 10 mg/cm{sup 3}. For some of the experiments, the agar/gelatin foam was uniformly doped with metallic elements using soluble salts. Depending on the method of preparation, cell sizes were typically below 10 microns and for one process were below 1.0 micron.

  16. Normal calves produced after transfer of embryos cultured in a chemically defined medium supplemented with epidermal growth factor and insulin-like growth factor I following ovum pick up and in vitro fertilization in Japanese black cows.

    PubMed

    Sakagami, Nobutada; Umeki, Hidenobu; Nishino, Osamu; Uchiyama, Hiroko; Ichikawa, Kyoko; Takeshita, Kazuhisa; Kaneko, Etsushi; Akiyama, Kiyoshi; Kobayashi, Shuji; Tamada, Hiromichi

    2012-01-01

    The objective of this study was to examine whether high concentrations of epidermal growth factor (EGF) and/or insulin-like growth factor I (IGF-I) would have a beneficial effect on bovine embryo development in vitro and to obtain normal calves by using an ovum pick up method and embryo culture in a chemically defined medium. When compared with controls, EGF (100 or 200 ng/ml) or IGF-I (50 or 100 ng/ml) significantly increased the rate of embryos that developed into blastocysts during an 8-day culture after the in vitro fertilization of oocytes obtained from ovaries from a slaughterhouse. IGF-I induced a dose-dependent increase in cell number in both the inner cell mass and the trophectoderm, whereas EGF stimulated proliferation only in the inner cell mass. A combination of EGF (100 ng/ml) and IGF-I (50 ng/ml) produced an additive effect, and embryos developed into blastocysts at a comparatively high rate (27.9%) compared with controls (12.0%). A similar rate of development was achieved using a combination of EGF and IGF-I in the culture of embryos following ovum pick up by ultrasound-guided transvaginal follicular aspiration and in vitro fertilization, and 5 blastocysts that developed after the culture were transferred into uteri; two embryos implanted, and normal calves were born. These results suggest that the combined use of EGF and IGF-I makes bovine embryo culture in a chemically defined medium a practical and useful procedure for producing blastocysts, and its application to embryo culture following ovum pick up and in vitro fertilization could be useful for producing normal calves.

  17. Effects of temperature and medium composition on inhibitory activities of gossypol-related compounds against aflatoxigenic fungi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Effects of temperature and medium composition on growth/aflatoxin inhibitory activities of gossypol, gossypolone and apogossypolone against Aspergillus flavus and A. parasiticus were investigated. The compounds were tested in a Czapek agar medium at 25 C, 31 C and 37 C at a concentration of 100 µg ...

  18. [Utilization of LIN (lysine-indole-motility) medium for the preliminary identification of enteropathogenic bacteria].

    PubMed

    Bockemühl, J; Bednarek, I

    1975-07-01

    A multiple-test medium for the routine laboratory identification of enteropathogenic bacteria is described. The medium has the following formula: Bacto-peptone (Difco) 5 g; yeast extract (Difco) 3 g; casein tryptic digest peptone (Merek) 15 g; glucose 1 g; L-lysine-monohydrochloride (Merck, No. 5700) 5 g; NaCl 5 g; bromcresol purple 0.016 g; agar 2 g; distilled water 1000 ml; final pH 6.6. The medium is dispensed in amounts of 5 ml into tubes of 14 X 85 mm and autoclaved at 120 degrees C for 10 min. The tubes are tightly closed with rubber stoppers. - The medium is inoculated by stabbing to the bottom of the tube. Readings are made after over-night incubation at 37 degrees C. A scheme for the preliminary identification of enteropathogenic bacteria is given, based on LIM medium in conjunction with Kligler's iron agar, and the oxidase reaction.

  19. Comparison of the recoveries of Escherichia coli and total coliforms from drinking water by the MI agar method and the U.S. Environmental Protection Agency-approved membrane filter method.

    PubMed Central

    Brenner, K P; Rankin, C C; Sivaganesan, M; Scarpino, P V

    1996-01-01

    Drinking water regulations under the Final Coliform Rule require that total coliform-positive drinking water samples be examined for the presence of Escherichia coli or fecal coliforms. The current U.S. Environmental Protection Agency-approved membrane filter (MF) method for E. coli requires two media, an MF transfer, and a total incubation time of 28 h. A newly developed MF method, the MI agar method, containing indoxyl-beta-D-glucuronide and 4-methylumbelliferyl-beta-D-galactopyranoside for the simultaneous detection of E. coli and total coliforms, respectively, by means of their specific enzyme reactions, was compared with the approved method by the use of wastewater-spiked tap water samples. Overall, weighted analysis of variance (significance level, 0.05) showed that the new medium recoveries of total coliforms and E. coli were significantly higher than those of mEndo agar and nutrient agar plus MUG (4-methylumbelliferyl-beta-D-glucuronide), respectively, and the background counts were significantly lower than those of mEndo agar (< 5%). Generally, the tap water source, overall chlorine level, wastewater source, granular activated carbon treatment of the tap water, and method of grouping data by E. coli count for statistical analysis did not affect the performance of the new medium. PMID:8572697

  20. [GROWTH OF MICROMYCETES FROM DIFFERENT ECOLOGICAL NICHES ON AGAR NUTRIENT MEDIA].

    PubMed

    Kurchenko, I M; Yurieva, E M; Voychuk, S I

    2015-01-01

    Radial growth rate of (K(r)) 153 strains 6 species of micromycetes from different ecological niches was studied on 7 agar media: three standard (malt extract agar, potato-dextrose agar, Czapek's agar), and on agar media with plant polymers (carboxymethylcellulose, xylan, soluble starch and apple pectin). Endophytic and plant pathogenic strains (biotrophs) of all studied species did not differ significantly in their ability to grow on nutrient media of different composition--average values of K(r) for these two groups were the same (0,200 and 0,199 mm/h, respectively). Soil micromycetes (saprophytes) characterized by the lowest average growth rate (0,169 mm/h) and significantly differed from the endophytic and plant pathogenic ones. Average of the radial growth rates of studied microscopic fungi were higher on standard nutrient media than with plant polymers ones. Growth parameters of endophytes and plant pathogens of all studied species on various agar media differed from the soil strains. High growth rate of endophytic and plant pathogenic strains of Fusarium poae, Alternaria alternata and Ceratocystis sp. provides them the rapid colonization of plants. Penicillium funiculosum strains equally can exist as saprophytes in soil and as endophytic plant symbionts. A wide range of K(r) variation of endophytic dark pigmented Mycelia sterilia indicates the presence in this group of different species of micromycetes, which have no sporulation.

  1. Complex impedance and conductivity of agar-based ion-conducting polymer electrolytes

    NASA Astrophysics Data System (ADS)

    Nwanya, A. C.; Amaechi, C. I.; Udounwa, A. E.; Osuji, R. U.; Maaza, M.; Ezema, F. I.

    2015-04-01

    Agar-based electrolyte standing films with different salts and weak acids as ion and proton conductors were prepared and characterized by X-ray diffraction, UV-visible spectrophotometry, photoluminescence emission spectroscopy and electrochemical impedance spectroscopy. The salts used are lithium perchlorate (LiClO4) and potassium perchlorate (KClO4), while the weak acids used are acetic acid (CH3COOH) and lactic acid (C3H6O3). The values of the ion conductivity obtained for the agar-based polymer films are 6.54 × 10-8, 9.12 × 10-8, 3.53 × 10-8, 2.24 × 10-8 S/cm for the agar/acetic acid, agar/lactic acid, agar/LiClO4 and agar/KClO4 polymer films, respectively. As a function of temperature, the ion conductivity exhibits an Arrhenius behavior and the estimated activation energy is ≈0.1 eV for all the samples. The samples depicted high values of dielectric permittivity toward low frequencies which is due mostly to electrode polarization effect. The samples showed very high transparency (85-98 %) in the visible region, and this high transparency is one of the major requirements for application in electrochromic devices (ECD). The values of conductivity and activation energy obtained indicate that the electrolytes are good materials for application in ECD.

  2. Modification of kanamycin-esculin-azide agar to improve selectivity in the enumeration of fecal streptococci from water samples.

    PubMed Central

    Audicana, A; Perales, I; Borrego, J J

    1995-01-01

    Kanamycin-esculin-azide agar was modified by increasing the concentration of sodium azide to 0.4 g liter-1 and replacing kanamycin sulfate with 5 mg of oxolinic acid liter-1. The modification, named oxolinic acid-esculin-azide (OAA) agar, was compared with Slanetz-Bartley and KF agars by using drinking water and seawater samples. The OAA agar showed higher specificity, selectivity, and recovery efficiencies than those obtained by using the other media. In addition, no confirmation of typical colonies was needed when OAA agar was used, which significantly shortens the time of sample processing and increases the accuracy of the method. PMID:8534085

  3. Evaluation of CHROMagar STEC and STEC O104 Chromogenic Agar Media for Detection of Shiga Toxin-Producing Escherichia coli in Stool Specimens

    PubMed Central

    Ruckly, Corinne; Carle, Isabelle; Lejay-Collin, Monique

    2013-01-01

    The performance of CHROMagar STEC and CHROMagar STEC O104 (CHROMagar Microbiology, Paris, France) media for the detection of Shiga toxin-producing Escherichia coli (STEC) was assessed with 329 stool specimens collected over 14 months from patients with suspected STEC infections (June 2011 to August 2012). The CHROMagar STEC medium, after an enrichment broth step, allowed the recovery of the STEC strain from 32 of the 39 (82.1%) Shiga toxin-positive stool specimens, whereas the standard procedure involving Drigalski agar allowed the recovery of only three additional STEC strains. The isolates that grew on CHROMagar STEC medium belonged to 15 serotypes, including the prevalent non-sorbitol-fermenting (NSF) O157:H7, O26:H11, and O104:H4 serotypes. The sensitivity, specificity, and positive and negative predictive values for the CHROMagar STEC medium were between 89.1% and 91.4%, 83.7% and 86.7%, 40% and 51.3%, and 98% and 98.8%, respectively, depending on whether or not stx-negative eae-positive E. coli was considered atypical enteropathogenic E. coli (EPEC) or STEC that had lost Shiga toxin genes during infection. In conclusion, the good performance of CHROMagar STEC agar medium, in particular, the high negative predictive value, and its capacity to identify NSF O157:H7 as well as common non-O157 STEC may be useful for clinical bacteriology, public health, and reference laboratories; it could be used in addition to a method targeting Shiga toxins (detection of stx genes by PCR, immunodetection of Shiga toxins in stool specimens, or Vero cell cytotoxicity assay) as an alternative to O157 culture medium. This combined approach should allow rapid visualization of both putative O157 and non-O157 STEC colonies for subsequent characterization, essential for real-time surveillance of STEC infections and investigations of outbreaks. PMID:23284030

  4. CHROMagar Orientation Medium Reduces Urine Culture Workload

    PubMed Central

    Manickam, Kanchana; Karlowsky, James A.; Adam, Heather; Lagacé-Wiens, Philippe R. S.; Rendina, Assunta; Pang, Paulette; Murray, Brenda-Lee

    2013-01-01

    Microbiology laboratories continually strive to streamline and improve their urine culture algorithms because of the high volumes of urine specimens they receive and the modest numbers of those specimens that are ultimately considered clinically significant. In the current study, we quantitatively measured the impact of the introduction of CHROMagar Orientation (CO) medium into routine use in two hospital laboratories and compared it to conventional culture on blood and MacConkey agars. Based on data extracted from our Laboratory Information System from 2006 to 2011, the use of CO medium resulted in a 28% reduction in workload for additional procedures such as Gram stains, subcultures, identification panels, agglutination tests, and biochemical tests. The average number of workload units (one workload unit equals 1 min of hands-on labor) per urine specimen was significantly reduced (P < 0.0001; 95% confidence interval [CI], 0.5326 to 1.047) from 2.67 in 2006 (preimplementation of CO medium) to 1.88 in 2011 (postimplementation of CO medium). We conclude that the use of CO medium streamlined the urine culture process and increased bench throughput by reducing both workload and turnaround time in our laboratories. PMID:23363839

  5. [Analysis of bactericidal material generated by electrical devices advertising bactericidal ability against bacteria on the agar gel plates].

    PubMed

    Nishimura, Hidekazu

    2012-11-01

    Several Japanese companies sell electrical devices advertised as effective in inactivating viruses and killing bacteria by releasing special materials, e.g., Plasmacluster ions, Nanoe particle and minus ions, into the air. These companies claim that their devices killed bacteria on plates in their own experiments. We tested device effectiveness using the same experiments from the Plasmacluster ioniser SHARP Co., Japan, the Nanoe generator Panasonic Co., Japan, and the Vion KING JIM Co., Japan, to test their advertising claims. Bactericidal ability on agar plate was tested, using Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus cereus, and Enterococcus faecalis as follows: the medium containing a certain amount of each bacterium was put onto an agar plate and smeared. Plates were kept in a closed chamber (inner volume 14.4 m3) or a glove box (inner volume 0.2 m), with one of the devices run for 2 hours. Plates not exposed to any device were used as controls. Each plate was retrieved and put in an incubator to count the number of bacterial colonies formed on the plate. There was no significant difference in the number of colonies on plates exposed to devices compared to control, in the number for all devices, or in all bacteria tested in experiments in the 14.4 m3 chamber. These results strongly suggest that these devices have almost no bactericidal effect, at least in space exceeding this volume. Colony formation was suppressed in the glove box in all devices and in all bacteria tested except P. aeruginosa, although the degree of suppression differed among experiments. The colony formation suppression mechanism was analyzed, and indicated that:colony formation did not change even after the removal of Plasmacluster ions, Nanoe particles, or negative ions from the air, while colony formation was decreased drastically by the removal of ozone from space, which was revealed to be generated inevitably during device operation. These results strongly suggest that the

  6. Evaluation of the thin agar layer method for the recovery of pressure-injured and heat-injured Listeria monocytogenes.

    PubMed

    Lavieri, Nicolas A; Sebranek, Joseph G; Cordray, Joseph C; Dickson, James S; Jung, Stephanie; Manu, David K; Mendonça, Aubrey F; Brehm-Stecher, Byron F; Stock, Joseph; Stalder, Kenneth J

    2014-05-01

    A sublethally injured bacterial cell has been defined as a cell that survives a stress such as heating, freezing, acid treatment, or other antimicrobial intervention but can repair the cellular damage exerted by the stressor and later regain its original ability to grow. Consequently, sublethally injured cells are not likely to be included in conventional enumeration procedures, which could result in unrealistically low counts unless efforts are made to encourage recovery of the injured cells before enumeration. The objective of this study was to evaluate the use of the thin agar layer (TAL) method for the recovery of pressure-injured and heat-injured Listeria monocytogenes in a tryptic soy broth with 0.6% yeast extract system. Pressure injury consisted of treatment of a culture of mixed L. monocytogenes strains with high hydrostatic pressure at 400 or 600 MPa for 1 s, 2 min, 4 min, or 6 min at a process temperature of 12±2 °C. Heat injury consisted of treatment of a culture of mixed L. monocytogenes strains at 60±1 °C for 3, 6, or 9 min. Growth media were tryptic soy agar (TSA) with 0.6% yeast extract, modified Oxford medium (MOX), and TAL, which consisted of a 7-ml layer of TSA overlaid onto solidified MOX. Counts of viable L. monocytogenes on TAL were higher than those on MOX in the heat-injury experiment but not in the pressure-injury experiment. Therefore, the effectiveness of the TAL method may be specific to the type of injury applied to the microorganism and should be investigated in a variety of cellular injury scenarios.

  7. Performance of CHROMAGAR candida and BIGGY agar for identification of yeast species

    PubMed Central

    Yücesoy, Mine; Marol, Serhat

    2003-01-01

    Background The importance of identifying the pathogenic fungi rapidly has encouraged the development of differential media for the presumptive identification of yeasts. In this study two differential media, CHROMagar Candida and bismuth sulphite glucose glycine yeast agar, were evaluated for the presumptive identification of yeast species. Methods A total number of 270 yeast strains including 169 Candida albicans, 33 C. tropicalis, 24 C. glabrata, 18 C. parapsilosis, 12 C. krusei, 5 Trichosporon spp., 4 C. kefyr, 2 C. lusitaniae, 1 Saccharomyces cerevisiae and 1 Geotrichum candidum were included. The strains were first identified by germ tube test, morphological characteristics on cornmeal tween 80 agar and Vitek 32 and API 20 C AUX systems. In parallel, they were also streaked onto CHROMagar Candida and bismuth sulphite glucose glycine yeast agar plates. The results were read according to the color, morphology of the colonies and the existance of halo around them after 48 hours of incubation at 37°C. Results The sensitivity and specificity values for C. albicans strains were found to be 99.4, 100% for CHROMagar Candida and 87.0, 75.2% for BiGGY agar, respectively. The sensitivity of CHROMagar Candida to identify C. tropicalis, C. glabrata and C. krusei ranged between 90.9 and 100% while the specificity was 100%. The sensitivity rates for BiGGY agar were 66.6 and 100% while the specificity values were found to be 95.4 and 100% for C. tropicalis and C. krusei, respectively. Conclusions It can be concluded that the use of CHROMagar Candida is an easy and reliable method for the presumptive identification of most commonly isolated Candida species especially C. albicans, C. tropicalis and C. krusei. The lower sensitivity and specificity of BiGGY agar to identify commonly isolated Candida species potentially limits the clinical usefulness of this agar. PMID:14613587

  8. Preparation and characterization of bio-nanocomposite films of agar and silver nanoparticles: laser ablation method.

    PubMed

    Rhim, Jong-Whan; Wang, Long-Feng; Lee, Yonghoon; Hong, Seok-In

    2014-03-15

    Silver nanoparticles (AgNPs) were prepared by a laser ablation method and composite films with the AgNPs and agar were prepared by solvent casting method. UV-vis absorbance test and transmission electron microscopy (TEM) analysis results revealed that non-agglomerated spherical AgNPs were formed by the laser ablation method. The surface color of the resulting agar/AgNPs films exhibited the characteristic plasmonic effect of the AgNPs with the maximum absorption peaks of 400-407 nm. X-ray diffraction (XRD) test results also exhibited characteristic AgNPs crystals with diffraction peaks observed at 2θ values of 38.39°, 44.49°, and 64.45°, which were corresponding to (111), (200), and (220) crystallographic planes of face-centered cubic (fcc) silver crystals, respectively. Thermogravimetric analysis (TGA) results showed that thermal stability of the agar/AgNPs composite films was increased by the inclusion of metallic silver. Water vapor barrier properties and surface hydrophobicity of the agar/AgNPs films increased slightly with the increase in AgNPs content but they were not statistically significant (p>0.05), while mechanical strength and stiffness of the composite films decreased slightly (p<0.05). The agar/AgNPs films exhibited distinctive antimicrobial activity against both Gram-positive (Listeria monocytogenes) and Gram-negative (Escherichia coli O157:H7) bacterial pathogens.

  9. Strongyloidiasis detected by the agar plate culture method among patients infected by HIV.

    PubMed

    Urdez-Hernández, E; Jiménez-Galán, S; Antonio-Manríquez, M; DE León-Juárez, E A; Terrazas-Estrada, J J; Hernández-García, M C; García-Zaldívar, P; Estrada-Aguilera, A

    1999-10-01

    To evaluate the rate of strongyloidiasis among HIV/AIDS patients, stools and duodenal juice were examined using the agar plate culture method. From January to June 1993, a total of 60 HIV/AIDS patients were required for duodenal aspirate and three serial samples of freshly passed stools. Stools and duodenal aspirate were dispensed on an agar plate culture; after incubation at 28 degrees C during 48 h, screening of plates was made at 10 x. The presence of furrows and worms of short buccal chamber and prominent genital primordium were positive for Strongyloides stercoralis. Most patients were men (91.7%); their mean age, of 33.9 years (SD +/- 10.6); their median CD4(+) T-cells count, of 105/microL (range of 12 to 646). S. stercoralis was detected in three patients (5%). In duodenal juice, the three patients showed the parasite, but in feces, only two (3.3%). In these two individuals, the worms were found in feces by agar culture and Faust's concentration method. The rate of S. stercoralis in feces of HIV/AIDS individuals (3.3%) by agar culture method was similar to that formerly reported from the general Mexican population (2.9%) using standard concentration procedures. Hence, in this immunocompromised population of a low prevalence city, there was no advantage to using an agar plate culture for strongyloidiasis.

  10. Characterization of bionanocomposite films prepared with agar and paper-mulberry pulp nanocellulose.

    PubMed

    Reddy, Jeevan Prasad; Rhim, Jong-Whan

    2014-09-22

    Crystallized nanocellulose (CNC) was separated from paper-mulberry (Broussonetia kazinoki Siebold) bast pulp by sulfuric acid hydrolysis method and they were blended with agar to prepare bionanocomposite films. The effect of CNC content (1, 3, 5 and 10 wt% based on agar) on the mechanical, water vapor permeability (WVP), and thermal properties of the nanocomposites were studied. Changes of the cellulose fibers in structure, morphology, crystallinity, and thermal properties of the films were evaluated using FT-IR, TEM, SEM, XRD, and TGA analysis methods. The CNC was composed of fibrous and spherical or elliptic granules of nano-cellulose with sizes of 50-60 nm. Properties of agar film such as mechanical and water vapor barrier properties were improved significantly (p<0.05) by blending with the CNC. The tensile modulus and tensile strength of agar film increased by 40% and 25%, respectively, in the composite film with 5 wt% of CNC, and the WVP of agar film decreased by 25% after formation of nanocomposite with 3 wt% of CNC. The CNC obtained from the paper-mulberry bast pulp can be used as a reinforcing agent for the preparation of bio-nanocomposites, and they have a high potential for the development of completely biodegradable food packaging materials.

  11. Strategies to improve the mechanical strength and water resistance of agar films for food packaging applications.

    PubMed

    Sousa, Ana M M; Gonçalves, Maria P

    2015-11-05

    Agar films possess several properties adequate for food packaging applications. However, their high cost-production and quality variations caused by physiological and environmental factors affecting wild seaweeds make them less attractive for industries. In this work, native (NA) and alkali-modified (AA) agars obtained from sustainably grown seaweeds (integrated multi-trophic aquaculture) were mixed with locust bean gum (LBG) to make 'knife-coated' films with fixed final concentration (1 wt%) and variable agar/LBG ratios. Agar films were easier to process upon LBG addition (viscosity increase and gelling character decrease of the film-forming solutions observed by dynamic oscillatory and steady shear measurements). The mechanical properties and water resistance were optimal for films with 50 and/or 75% LBG contents and best in the case of NA (cheaper to extract). These findings can help reduce the cost-production of agar packaging films. Moreover, the controlled cultivation of seaweeds can provide continuous and reliable feedstock for transformation industries.

  12. Immobilization of urease from pigeonpea (Cajanus cajan) on agar tablets and its application in urea assay.

    PubMed

    Mulagalapalli, Swati; Kumar, Sandeep; Kalathur, Ravi Charan Reddy; Kayastha, Arvind M

    2007-09-01

    The pigeonpea urease was immobilized on agar, a common gelling substance. The tablet strips were used as moulds to cast agar tablets of uniform shape and size. The time and temperature of solidification of agar was 6 min and 44 degrees C, respectively. The 5 % agar (w/v) and 0.019 mg protein/agar tablet yielded an optimum immobilization of 51.7%. The optimum pH was shifted through 0.2 U (from 7.3 to 7.5) towards basic side upon immobilization. The optimum temperature of soluble and immobilized urease was 30 degrees C and 60 degrees C, respectively, showing the improvement in thermal stability of urease. There was an increase in K m from 3.23 to 5.07 mM after immobilization. The half-lives of soluble and immobilized urease were 21 and 53 days, respectively, at pH 7.3 and 4 degrees C. The urea was estimated in different blood samples with the help of immobilized urease and the results were consistent with those from clinical pathology laboratory through an autoanalyzer (Zydus Co., Rome, Italy).

  13. Antimicrobial and physical-mechanical properties of agar-based films incorporated with grapefruit seed extract.

    PubMed

    Kanmani, Paulraj; Rhim, Jong-Whan

    2014-02-15

    The use of synthetic petroleum based packaging films caused serious environmental problems due to their difficulty in recycling and poor biodegradability. Therefore, present study was aimed to develop natural biopolymer-based antimicrobial packaging films as an alternative for the synthetic packaging films. As a natural antimicrobial agent, grapefruit seed extract (GSE) has been incorporated into agar to prepare antimicrobial packaging film. The films with different concentrations of GSE were prepared by a solvent casting method and the resulting composite films were examined physically and mechanically. In addition, the films were characterized by FE-SEM, XRD, FT-IR and TGA. The incorporation of GSE caused increase in color, UV barrier, moisture content, water solubility and water vapor permeability, while decrease in surface hydrophobicity, tensile strength and elastic modulus of the films. As the concentration of GSE increased from 0.6 to 13.3 μg/mL, the physical and mechanical properties of the films were affected significantly. The addition of GSE changed film microstructure of the film, but did not influence the crystallinity of agar and thermal stability of the agar-based films. The agar/GSE films exhibited distinctive antimicrobial activity against three test food pathogens, such as Listeria monocytogenes, Bacillus cereus and Escherichia coli. These results suggest that agar/GSE films have potential to be used in an active food packaging systems for maintaining food safety and extending the shelf-life of the packaged food.

  14. Effects of shape and size of agar gels on heating uniformity during pulsed microwave treatment.

    PubMed

    Soto-Reyes, Nohemí; Temis-Pérez, Ana L; López-Malo, Aurelio; Rojas-Laguna, Roberto; Sosa-Morales, María Elena

    2015-05-01

    Model gel systems with different shape (sphere, cylinder, and slab) and size (180 and 290 g) were prepared with agar (5%) and sucrose (5%). Dielectric constant (ε'), loss factor (ε"), thermophysical properties, and temperature distribution of the model system were measured. Each agar model system was immersed and suspended in water, and then, heated in a microwave oven with intermittent heating until the core temperature reached 50 °C. The ε' and ε" of agar gels decreased when frequency increased. The density and thermal conductivity values of the agar gels were 1033 kg/m(3) and 0.55 W/m °C, respectively. The temperature distribution of sphere, cylinder, and slab was different when similar power doses were applied. The slab reached 50 °C in less time (10 min) and showed a more uniform heating than spheres and cylinders in both sizes. Agar model systems of 180 g heated faster than those of 290 g. The coldest point was the center of the model systems in all studied cases. Shape and size are critical food factors that affect the heating uniformity during microwave heating processes.

  15. Herbal Products and Supplements

    MedlinePlus

    ... of dietary supplement that contains one or more herbs.Herbal health products and supplements are available in ... wort.Are herbal health products and supplements safe?Herbs aren't necessarily safer than the ingredients in ...

  16. Mutations in Arabidopsis thaliana genes involved in the tryptophan biosynthesis pathway affect root waving on tilted agar surfaces

    NASA Technical Reports Server (NTRS)

    Rutherford, R.; Gallois, P.; Masson, P. H.

    1998-01-01

    Arabidopsis thaliana roots grow in a wavy pattern upon a slanted surface. A novel mutation in the anthranilate synthase alpha 1 (ASA1) gene, named trp5-2wvc1, and mutations in the tryptophan synthase alpha and beta 1 genes (trp3-1 and trp2-1, respectively) confer a compressed root wave phenotype on tilted agar surfaces. When trp5-2wvc1 seedlings are grown on media supplemented with anthranilate metabolites, their roots wave like wild type. Genetic and pharmacological experiments argue that the compressed root wave phenotypes of trp5-2wvc1, trp2-1 and trp3-1 seedlings are not due to reduced IAA biosynthetic potential, but rather to a deficiency in L-tryptophan (L-Trp), or in a L-Trp derivative. Although the roots of 7-day-old seedlings possess higher concentrations of free L-Trp than the shoot as a whole, trp5-2wvc1 mutants show no detectable alteration in L-Trp levels in either tissue type, suggesting that a very localized shortage of L-Trp, or of a L-Trp-derived compound, is responsible for the observed phenotype.

  17. Homogeneous Matrix Deposition on Dried Agar for MALDI Imaging Mass Spectrometry of Microbial Cultures

    NASA Astrophysics Data System (ADS)

    Hoffmann, Thomas; Dorrestein, Pieter C.

    2015-11-01

    Matrix deposition on agar-based microbial colonies for MALDI imaging mass spectrometry is often complicated by the complex media on which microbes are grown. This Application Note demonstrates how consecutive short spray pulses of a matrix solution can form an evenly closed matrix layer on dried agar. Compared with sieving dry matrix onto wet agar, this method supports analyte cocrystallization, which results in significantly more signals, higher signal-to-noise ratios, and improved ionization efficiency. The even matrix layer improves spot-to-spot precision of measured m/z values when using TOF mass spectrometers. With this technique, we established reproducible imaging mass spectrometry of myxobacterial cultures on nutrient-rich cultivation media, which was not possible with the sieving technique.

  18. Improved soft-agar colony assay in a fluid processing apparatus.

    PubMed

    Forsman, A D; Herpich, A R; Chapes, S K

    1999-01-01

    The standard method for quantitating bone marrow precursor cells has been to count the number of colony-forming units that form in semisolid (0.3%) agar. Recently we adapted this assay for use in hardware, the Fluid Processing Apparatus, that is flown in standard payload lockers of the space shuttle. When mouse or rat macrophage colony-forming units were measured with this hardware in ground-based assays, we found significantly more colony growth than that seen in standard plate assays. The improved growth correlates with increased agar thickness but also appears to be due to properties inherent to the Fluid Processing Apparatus. This paper describes an improved method for determining bone marrow macrophage precursor numbers in semisolid agar.

  19. [DNA and chemical analyses of commercial fly agaric-related products].

    PubMed

    Maruyama, Takuro; Kawahara, Nobuo; Fukiharu, Toshimitsu; Yokoyama, Kazumasa; Makino, Yukiko; Goda, Yukihiro

    2005-04-01

    Since June 6, 2002, psilocin and psilocybin-containing fungi (commonly called "magic mushrooms") have been regulated by the Narcotics and Psychotropics Control Law in Japan. However, various fly agaric-related products are now entering the Japanese market via the internet. In this study, fly agaric-related products available in this way were investigated for raw materials by DNA analysis and for additives by chemical analysis. Nucleotide sequence analysis of the mitochondrial 12S rDNA region suggested that these fly agaric-related products originate from A. muscaria or A. muscaria var. persicina. Furthermore, they were classified into three strains based on the ITS2-LSU nucleotide sequence. Harmine derivatives and/or tryptamine derivatives were detected in some of these products by LC/MS analysis. In accordance with this, the matK gene of Peganum harmala was found in all of the harmine derivative-containing samples.

  20. Expression of an accessory cell phenotype by hairy cells during lymphocyte colony formation in agar culture.

    PubMed

    Farcet, J P; Gourdin, M F; Testa, U; Andre, C; Jouault, H; Reyes, F

    1983-01-01

    Human T lymphocytes require the cooperation of accessory cells to generate lymphocyte colonies in agar culture under PHA stimulation. Various hairy cell enriched fractions, as well as normal monocytes, have been found to be able to initiate colony formation by normal lymphocytes. Leukemic monocytes from CMML patients were also effective, but not the leukemic lymphocytes from CLL patients. The phenotype expressed by HC in agar colonies was further studied using cell surface and enzymatic markers. We have concluded that HC in agar culture in the presence of both normal T lymphocytes and PHA lose the B phenotype that they express in vivo and function like an accessory cell in contrast to normal or leukemic B lymphocytes.

  1. Agar blue localization of small pulmonary nodules and ground glass opacifications for thoracoscopic resection

    PubMed Central

    2016-01-01

    Background Screening for lung cancer using high resolution computed tomography (CT) has produced encouraging early results. Extremely small nodules and non-palpable areas of opacifications are able to be detected, but pose a challenge to the thoracic surgeon trying to resect these areas. Methods Forty five patients with ground glass opacifications (GGOs) or small pulmonary nodules underwent pre-operative CT-guided placement of methylene blue dyed agar and/or hook wire needle localization prior to thoracoscopic resection. Progel was applied to any intraoperative air leaks observed after successful resection. Results All lesions were successfully excised thoracoscopically. The blue agar aided in localization of these areas and did not affect the histological architecture during pathologic evaluation. Conclusions Careful pre-operative evaluation and planning, including use of selective CT-guided blue agar localization and hook wire placement, may greatly assist in thoracoscopically locating and resecting these often difficult-to-visualize lesions. PMID:28066669

  2. Agar-block microcosms for controlled plant tissue decomposition by aerobic fungi.

    PubMed

    Schilling, Jonathan S; Jacobson, K Brook

    2011-02-03

    The two principal methods for studying fungal biodegradation of lignocellulosic plant tissues were developed for wood preservative testing (soil-block; agar-block). It is well-accepted that soil-block microcosms yield higher decay rates, fewer moisture issues, lower variability among studies, and higher thresholds of preservative toxicity. Soil-block testing is thus the more utilized technique and has been standardized by American Society for Testing and Materials (ASTM) (method D 1413-07). The soil-block design has drawbacks, however, using locally-variable soil sources and in limiting the control of nutrients external (exogenous) to the decaying tissues. These drawbacks have emerged as a problem in applying this method to other, increasingly popular research aims. These modern aims include degrading lignocellulosics for bioenergy research, testing bioremediation of co-metabolized toxics, evaluating oxidative mechanisms, and tracking translocated elements along hyphal networks. Soil-blocks do not lend enough control in these applications. A refined agar-block approach is necessary. Here, we use the brown rot wood-degrading fungus Serpula lacrymans to degrade wood in agar-block microcosms, using deep Petri dishes with low-calcium agar. We test the role of exogenous gypsum on decay in a time-series, to demonstrate the utility and expected variability. Blocks from a single board rip (longitudinal cut) are conditioned, weighed, autoclaved, and introduced aseptically atop plastic mesh. Fungal inoculations are at each block face, with exogenous gypsum added at interfaces. Harvests are aseptic until the final destructive harvest. These microcosms are designed to avoid block contact with agar or Petri dish walls. Condensation is minimized during plate pours and during incubation. Finally, inoculum/gypsum/wood spacing is minimized but without allowing contact. These less technical aspects of agar-block design are also the most common causes of failure and the key source of

  3. Improvement of Polymyxin-Egg Yolk-Mannitol-Bromothymol Blue Agar for the Enumeration and Isolation of Bacillus cereus in Various Foods.

    PubMed

    Kang, Il-Byeong; Chon, Jung-Whan; Kim, Dong-Hyeon; Jeong, Dana; Kim, Hong-Seok; Kim, Hyunsook; Seo, Kun-Ho

    2017-03-01

    A modified polymyxin-egg yolk-mannitol-bromothymol blue agar (mPEMBA) was developed by supplementing polymyxin-egg yolk-mannitol-bromothymol blue agar (PEMBA) with trimethoprim to improve the selectivity for and recoverability of Bacillus cereus from naturally and artificially contaminated food samples. The number of B. cereus in mPEMBA was significantly higher than in PEMBA, indicating better recoverability (P < 0.05) in red pepper powder (PEMBA 0.80 ± 0.22 log CFU/g versus mPEMBA 1.95 ± 0.17 log CFU/g) and soybean paste (PEMBA 2.19 ± 0.18 log CFU/g versus mPEMBA 3.09 ± 0.13 log CFU/g). In addition, mPEMBA provided better visual differentiation of B. cereus colonies than PEMBA, which is attributable to the reduced number of competing microflora. We conclude that the addition of trimethoprim to PEMBA could generate a synergistic effect to improve selectivity for B. cereus .

  4. New Agar Technique Compared with Sand Flotation for Obtaining Salt Marsh Culicoides mississippiensis Hoffman (Diptera: Ceratopogonidae) Larvae,

    DTIC Science & Technology

    1979-12-26

    compared with 1% and 2% (wt/v) agar formulations for extracting Culicoides ndisaiooippiensis Hoffman larvae from marsh soil samples. The 1% agar formula...been used to recover larvae of biting midges (CuZ.,o;1aa spp .) from salt marsh substrate (soil) samples. They are: (1) sieve-flotation (Kettle and Lawson...Kettle et al., (1975) in which tabanid and culicoid larvae were successfully reared in agar media, we decided that one possibility was to replace the

  5. Comparison and Recovery of Escherichia coli and Thermotolerant Coliforms in Water with a Chromogenic Medium Incubated at 41 and 44.5°C

    PubMed Central

    Alonso, Jose L.; Soriano, Adela; Carbajo, Oscar; Amoros, Inmaculada; Garelick, Hemda

    1999-01-01

    This study compared the performance of a commercial chromogenic medium, CHROMagarECC (CECC), and CECC supplemented with sodium pyruvate (CECCP) with the membrane filtration lauryl sulfate-based medium (mLSA) for enumeration of Escherichia coli and non-E. coli thermotolerant coliforms (KEC). To establish that we could recover the maximum KEC and E. coli population, we compared two incubation temperature regimens, 41 and 44.5°C. Statistical analysis by the Fisher test of data did not demonstrate any statistically significant differences (P = 0.05) in the enumeration of E. coli for the different media (CECC and CECCP) and incubation temperatures. Variance analysis of data performed on KEC counts showed significant differences (P = 0.01) between KEC counts at 41 and 44.5°C on both CECC and CECCP. Analysis of variance demonstrated statistically significant differences (P = 0.05) in the enumeration of total thermotolerant coliforms (TTCs) on CECC and CECCP compared with mLSA. Target colonies were confirmed to be E. coli at a rate of 91.5% and KEC of likely fecal origin at a rate of 77.4% when using CECCP incubated at 41°C. The results of this study showed that CECCP agar incubated at 41°C is efficient for the simultaneous enumeration of E. coli and KEC from river and marine waters. PMID:10427079

  6. Use of the Soft-agar Overlay Technique to Screen for Bacterially Produced Inhibitory Compounds

    PubMed Central

    Hockett, Kevin L.; Baltrus, David A.

    2017-01-01

    The soft-agar overlay technique was originally developed over 70 years ago and has been widely used in several areas of microbiological research, including work with bacteriophages and bacteriocins, proteinaceous antibacterial agents. This approach is relatively inexpensive, with minimal resource requirements. This technique consists of spotting supernatant from a donor strain (potentially harboring a toxic compound(s)) onto a solidified soft agar overlay that is seeded with a bacterial test strain (potentially sensitive to the toxic compound(s)). We utilized this technique to screen a library of Pseudomonas syringae strains for intraspecific killing. By combining this approach with a precipitation step and targeted gene deletions, multiple toxic compounds produced by the same strain can be differentiated. The two antagonistic agents commonly recovered using this technique are bacteriophages and bacteriocins. These two agents can be differentiated using two simple additional tests. Performing a serial dilution on a supernatant containing bacteriophage will result in individual plaques becoming less in number with greater dilution, whereas serial dilution of a supernatant containing bacteriocin will result a clearing zone that becomes uniformly more turbid with greater dilution. Additionally, a bacteriophage will produce a clearing zone when spotted onto a fresh soft agar overlay seeded with the same strain, whereas a bacteriocin will not produce a clearing zone when transferred to a fresh soft agar lawn, owing to the dilution of the bacteriocin. PMID:28117830

  7. Investigation of dental alginate and agar impression materials as a brain simulant for ballistic testing.

    PubMed

    Falland-Cheung, Lisa; Piccione, Neil; Zhao, Tianqi; Lazarjan, Milad Soltanipour; Hanlin, Suzanne; Jermy, Mark; Waddell, J Neil

    2016-06-01

    Routine forensic research into in vitro skin/skull/brain ballistic blood backspatter behavior has traditionally used gelatin at a 1:10 Water:Powder (W:P) ratio by volume as a brain simulant. A limitation of gelatin is its high elasticity compared to brain tissue. Therefore this study investigated the use of dental alginate and agar impression materials as a brain simulant for ballistic testing. Fresh deer brain, alginate (W:P ratio 91.5:8.5) and agar (W:P ratio 81:19) specimens (n=10) (11×22×33mm) were placed in transparent Perspex boxes of the same internal dimensions prior to shooting with a 0.22inch caliber high velocity air gun. Quantitative analysis to establish kinetic energy loss, vertical displacement elastic behavior and qualitative analysis to establish elasticity behavior was done via high-speed camera footage (SA5, Photron, Japan) using Photron Fastcam Viewer software (Version 3.5.1, Photron, Japan) and visual observation. Damage mechanisms and behavior were qualitatively established by observation of the materials during and after shooting. The qualitative analysis found that of the two simulant materials tested, agar behaved more like brain in terms of damage and showed similar mechanical response to brain during the passage of the projectile, in terms of energy absorption and vertical velocity displacement. In conclusion agar showed a mechanical and subsequent damage response that was similar to brain compared to alginate.

  8. Use of Mueller-Hinton broth and agar in the germ tube test.

    PubMed

    Mattei, Antonella Souza; Alves, Sydney Hartz; Severo, Cecília Bittencourt; Guazzelli, Luciana da Silva; Oliveira, Flávio de Mattos; Severo, Luiz Carlos

    2014-01-01

    Candida albicans is often isolated from clinical samples, thus its presumptive differentiation from other species of the same genus can be based on its ability to form the germ tube in human serum. Nevertheless, there are two other species that share this characteristic: C. dubliniensis and C. africana. The aim of this study was to compare four different substrates to perform the germ tube (GT) test. The Candida spp. isolates were identified using a manual system (135 C. albicans, 24 C. tropicalis and one C. dubliniensis). The germ tube test was performed with fresh, previously frozen serum and Mueller-Hinton (MH) broth and agar. GT was observed in 96% (130/136) of the isolates through the fresh serum technique, 94% (128/136) through previously frozen serum, 92% (125/136) in MH agar, and 90% (122/136) in MH broth. The sensitivity of each test was higher than 90%, with 100% specificity. Both the MH agar and broth were able to identify the true positives, and false positives were not found. However, some C. albicans isolates were not identified. MH agar and broth may be used in laboratory for the rapid presumptive identification of C. albicans, as an alternative method for germ tube test.

  9. Alternative plasticizers for the production of thermo-compressed agar films

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One percent agar (% wt) was dissolved in the deep eutectic solvent (DES), (2-hydroxyethyl) trimethylammonium chloride/urea at a 1:2 molar ratio, and successfully Electrospun into nanofibers. An existing electrospinning set-up, operated at 50 deg C, was adapted for use with an ethanol bath to collect...

  10. Evaluation of an Automated Instrument for Inoculating and Spreading Samples onto Agar Plates.

    PubMed

    Glasson, J H; Guthrie, L H; Nielsen, D J; Bethell, F A

    2008-04-01

    The findings from a preliminary assessment of a new instrument designed for the inoculation and spreading of specimens for microbiological analysis onto agar plates are described. The study found that the instrument was able to select full or biplates from a number of input cassettes, each containing different agar types. Samples were then inoculated by the instrument onto the agar surfaces and spread by a novel plastic applicator. Following this, the instrument labeled the plates and sorted them into a number of specified output stations. It was found that the instrument was able to inoculate and spread samples over a greater proportion of the agar plate surface than the manual loop-to-plate method. As a consequence, up to 44% more usable colonies were produced per plate from clinical specimens and standard cultures. Viable counts showed that the instrument was able to detect as few as 10(2) CFU/ml in fluids and also facilitated the enumeration of organisms, particularly in specimens such as urine.

  11. Development of hyperspectral imaging technique for salmonella enteritidis and typhimurium on agar plates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salmonella is a common cause of foodborne disease resulting from the consumption of contaminated food products. Although a direct plating method is widely used for presumptive positive screening of pathogenic Salmonella colonies on agar plates, it is labor-intensive, time-consuming and also prone to...

  12. Analysis of beta-hemolysis in human blood agars by Streptococcus pyogenes.

    PubMed

    Zomorodian, Kamiar; Rahimi, Mohammad Javad; Safaei, Akbar; Bazargani, Abdollah; Motamadi, Marjan; Kharazi, Mahboobeh; Mostaghni, Setareh; Pakshir, Keyvan; Ghaedi, Hamid; Afsarian, Mohammad Hossein

    2011-06-01

    The aim of the study was to assess the reliability of human blood agar media (HuBA) in identifying Streptococcus pyogenes by hemolysis analysis. We analyze several factors that might affect the accuracy of HuBA media for microbial analysis, including incubation time, blood group, Rh factor and presence of antistreptolysin-o.

  13. Rapid diagnosis of acanthamoeba keratitis using non-nutrient agar with a lawn of E. coli

    PubMed Central

    2013-01-01

    Background A patient presented with a corneal foreign body in his only eye. He was treated with prophylactic antibiotics and sent home, but deteriorated. Findings He returned to the hospital 5 days later, and on slit-lamp examination, there was ciliary injection, corneal oedema and a 1 mm × 1 mm corneal abscess with mild anterior uveitis. Corneal scrapings were taken for culture on a non-nutrient agar with a lawn of Escherichia coli, on chocolate agar and on blood agar. He was treated with fortified gentamicin and cefazolin drops. He improved and was discharged 4 days after admission. On day 5, the culture results showed acanthamoeba. He was brought back to the hospital and treated with hourly chlorhexidine drops, ofloxacin six times daily and neomycin/dexamethasone drops once daily. On day 7, he was discharged to continue treatment at home, at which time his visual acuity in that eye was 6/9, and slit-lamp examination showed punctate keratitis and a stromal opacity with mild peripheral infiltration. Conclusions Culture on non-nutrient agar with a lawn of E. coli is a rapid, reliable and less invasive alternative to corneal biopsy for the diagnosis of acanthamoeba infection. We suggest using this method where acanthamoeba is suspected. Owing to the risk of corneal abscess, orthokeratology should be avoided in an amblyopic patient or an only eye. Acanthamoeba infection may be masked by other eye diseases. PMID:23514313

  14. Radiation survival of murine and human melanoma cells utilizing two assay systems: monolayer and soft agar.

    PubMed Central

    Yohem, K. H.; Slymen, D. J.; Bregman, M. D.; Meyskens, F. L.

    1988-01-01

    The radiation response of murine and human melanoma cells assayed in bilayer soft agar and monolayer was examined. Cells from the murine melanoma Cloudman S91 CCL 53.1 cell line and three human melanoma cell strains (C8146C, C8161, and R83-4) developed in our laboratory were irradiated by single dose X-rays and plated either in agar or on plastic. D0 values were the same within 95% confidence intervals for cells from the human melanoma cell strains C8146C, C8161, and R83-4 but were dissimilar for the murine cell line CCL 53.1 Dq values were different for all cells studied. The shape of the survival curve for all four melanomas was not identical for cells assayed in soft agar versus cells grown on plastic. This would indicate that apparent radiosensitivity was influenced by the method of assay although there were no apparent consistent differences between the curves generated by monolayer or bilayer soft agar assays. PMID:3348949

  15. In vitro growth of bioactive nanostructured apatites via agar-gelatin hybrid hydrogel.

    PubMed

    Deng, Yi; Zhao, Xianghui; Zhou, Yongsheng; Zhu, Peizhi; Zhang, Li; Wei, Shicheng

    2013-12-01

    Biomimetic synthesis of bone-like carbonated apatite with good biocompatibility is a promising strategy for the development of novel biomaterials for bone engineering applications. Most research efforts have been focused on only protein-based or only polysaccharide-based template for synthesis of apatite minerals. To understand the cooperative roles of gelatin and polysaccharide playing in the biomineralization, agar hydrogel, gelatin and agar-gelatin hybrid hydrogel were respectively introduced as mineralization matrix for the in vitro growth of apatite in the study. It was shown that bundle-like carbonated apatite was successfully prepared in agar-gelatin hybrid hydrogel for the first time, through the interaction between apatite and matrix macromolecule under physiological temperature. Moreover, the in vitro biocompatibility of the prepared nanostructured apatite crystals was investigated using CCK-8 assay and alkaline phosphatase activity of osteoblast-like MC3T3-E1. Compared with HA synthesized by traditional method, the obtained apatite in agar-gelatin hybrid hydrogel could provide significantly higher cell viability and alkaline phosphatase activity. Through the study, we could better understand the role of gelatin and polysaccharide in bone formation process, and the product is a promising candidate to be used in bone tissue engineering.

  16. Applying Agar's Concept of "Languaculture" to Explain Asian Students' Experiences in the Australian Tertiary Context

    ERIC Educational Resources Information Center

    Norris, Lindy; Tsedendamba, Nara

    2015-01-01

    This paper reports part of a broader qualitative case study of Asian students "translation" (Agar, 2006) to study in an Australian university. The paper is concerned with the experiences of eight participants and their involvement in a training programme in the use of language learning strategies (LLS) to support their engagement with…

  17. The relationship between growth in agar, karyotype and prognosis in acute leukaemia.

    PubMed

    Gustavsson, A; Mitelman, F; Olofsson, T; Olsson, I

    1984-04-01

    The growth pattern in agar culture and the karyotype of bone marrow cells were studied in 79 patients with untreated acute non-lymphocytic leukaemia (ANLL). Results were divided into the following groups: (A) colony and cluster formation; (B) growth of less than 600 small clusters per 10(5) cells; (C) growth of more than 600 small clusters; (D) no growth in agar. Cytogenetically, the patients were divided into 3 categories: NN, normal metaphases only; AN, both abnormal and normal metaphases and AA, abnormal metaphases only. An association was seen between growth pattern and karyotype: the majority of NN patients (33/37) belonged to group (A + B) while in group (C + D) 20/24 patients were AN or AA. 37 patients were prognostically evaluable. The growth pattern in agar but not the cytogenetic pattern had prognostic implications. 25 patients with acute lymphocytic leukaemia (ALL) were also studied at diagnosis. Different growth patterns in agar had no impact on prognosis. No relationship was detected between growth pattern and karyotype in ALL.

  18. Increased sensitivity of routine laboratory detection of Strongyloides stercoralis and hookworm by agar-plate culture.

    PubMed

    Jongwutiwes, S; Charoenkorn, M; Sitthichareonchai, P; Akaraborvorn, P; Putaporntip, C

    1999-01-01

    The efficacy of agar-plate culture has been evaluated for the detection of Strongyloides stercoralis and hookworm, compared with direct smear, the formalin-ether sedimentation technique and the filter-paper method. Of 1085 stool samples from the routine laboratory service at King Chulalongkorn Memorial Hospital in Bangkok, 241 samples harboured S. stercoralis, 153 hookworm and 2 Rhabditis hominis. The recovery rate of S. stercoralis by agar-plate culture is significantly superior to the other methods (P < 0.005). The ratios of positive results from the methods used to the total number of S. stercoralis-positive cases were as follows: 1:1.03 by agar-plate culture, 1:1.85 by the filter-paper method, 1:1.98 by the sedimentation technique and 1:10.48 by direct stool smear. A similar trend of the efficacy ratio of each method was obtained for hookworm detection. The characteristic furrows left by hookworm larvae, and larvae and adults of S. stercoralis could be used for preliminary species identification. Daily search for furrows on agar plates for up to 6 consecutive days resulted in an increased sensitivity for diagnosis of both S. stercoralis and hookworm infections.

  19. Automated agar plate streaker: a linear plater on Society for Biomolecular Sciences standard plates.

    PubMed

    King, Gregory W; Kath, Gary S; Siciliano, Sal; Simpson, Neal; Masurekar, Prakash; Sigmund, Jan; Polishook, Jon; Skwish, Stephen; Bills, Gerald; Genilloud, Olga; Peláez, Fernando; Martín, Jesus; Dufresne, Claude

    2006-09-01

    Several protocols for bacterial isolation and techniques for aerobic plate counting rely on the use of a spiral plater to deposit concentration gradients of microbial suspensions onto a circular agar plate to isolate colony growth. The advantage of applying a gradient of concentrations across the agar surface is that the original microbiological sample can be applied at a single concentration rather than as multiple serial dilutions. The spiral plater gradually dilutes the sample across a compact area and therefore saves time preparing dilutions and multiple agar plates. Commercial spiral platers are not automated and require manual sample loading. Dispensing of the sample volume and rate of gradients are often very limited in range. Furthermore, the spiral sample application cannot be used with rectangular microplates. Another limitation of commercial spiral platers is that they are useful only for dilute, filtered suspensions and cannot plate suspensions of coarse organic particles therefore precluding the use of many kinds of microorganism-containing substrata. An automated agar plate spreader capable of processing 99 rectangular microplates in unattended mode is described. This novel instrument is capable of dispensing discrete volumes of sample in a linear pattern. It can be programmed to dispense a sample suspense at a uniform application rate or across a decreasing concentration gradient.

  20. Comparison of the antibacterial activity of chelating agents using the agar diffusion method

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The agar diffusion assay was used to examine antibacterial activity of 2 metal chelators. Concentrations of 0 to 40 mM of ethylenediaminetetraacetic acid (EDTA) and ethylenediamine-N,N’-disuccinic acid (EDDS) were prepared in 1.0 M potassium hydroxide (KOH). The pH of the solutions was adjusted to 1...

  1. Hyperspectral image reconstruction using RGB color for foodborne pathogen detection on agar plates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper reports the latest development of a color vision technique for detecting colonies of foodborne pathogens grown on agar plates with a hyperspectral image classification model that was developed using full hyperspectral data. The hyperspectral classification model depended on reflectance sp...

  2. Hyperspectral image reconstruction using RGB color for foodborne pathogen detection on agar plates

    NASA Astrophysics Data System (ADS)

    Yoon, Seung-Chul; Shin, Tae-Sung; Park, Bosoon; Lawrence, Kurt C.; Heitschmidt, Gerald W.

    2014-03-01

    This paper reports the latest development of a color vision technique for detecting colonies of foodborne pathogens grown on agar plates with a hyperspectral image classification model that was developed using full hyperspectral data. The hyperspectral classification model depended on reflectance spectra measured in the visible and near-infrared spectral range from 400 and 1,000 nm (473 narrow spectral bands). Multivariate regression methods were used to estimate and predict hyperspectral data from RGB color values. The six representative non-O157 Shiga-toxin producing Eschetichia coli (STEC) serogroups (O26, O45, O103, O111, O121, and O145) were grown on Rainbow agar plates. A line-scan pushbroom hyperspectral image sensor was used to scan 36 agar plates grown with pure STEC colonies at each plate. The 36 hyperspectral images of the agar plates were divided in half to create training and test sets. The mean Rsquared value for hyperspectral image estimation was about 0.98 in the spectral range between 400 and 700 nm for linear, quadratic and cubic polynomial regression models and the detection accuracy of the hyperspectral image classification model with the principal component analysis and k-nearest neighbors for the test set was up to 92% (99% with the original hyperspectral images). Thus, the results of the study suggested that color-based detection may be viable as a multispectral imaging solution without much loss of prediction accuracy compared to hyperspectral imaging.

  3. Mercury in fruiting bodies of Fly Agaric Amanita muscaria (L.: Fr.) Pers. collected from Poland

    NASA Astrophysics Data System (ADS)

    Falandysz, J.; Lipka, K.

    2003-05-01

    Total mercury concentrations were determined in the fruiting bodies of Fly Agaric Amanita muscaria (L.: FL) Pers. and underlying soil substrate collected from several sites in Poland in 1993-2000 to evaluate mercury status as contaminant and bioindicating features of this species. The samples were collected from the spatially distant sites such as: Zaborski Landscape Park, Mierzeja Wiślana Landscape Park, Wdzydzki Landscape Park, Borecka Forest, Tucholskie Forest, Wieluńska Upland, the communities of Gubin, Manowo, Lubiana and Morag. Total mercury content of caps and stalks of Fly agaric varied widely depending on the sites examined. The range of the mean mercury concentrations for all 17 sites was between 96±10 and 1900±1400 ng/g dry wt for the caps and between 6l±32 and 920±760 ng/g dry wt for the stalks, while between 4.4±3.1 and 150±20 ng/g were noted for soil substrate samples from 9 sites examined. Fly agaric independently of the site examined showed relatively good capacity to accumulate total mercury and BCF values varied between 16±10 and 74±15 for the caps and between 11±8 and 42±10 for the stalks. Nevertheless, relatively high bioconcentration potential of mercury by Fly agaric seems to be specific for that species and under soil mercury concentrations noted no bioindication properties of this mushroom could be observed.

  4. Use of the Soft-agar Overlay Technique to Screen for Bacterially Produced Inhibitory Compounds.

    PubMed

    Hockett, Kevin L; Baltrus, David A

    2017-01-14

    The soft-agar overlay technique was originally developed over 70 years ago and has been widely used in several areas of microbiological research, including work with bacteriophages and bacteriocins, proteinaceous antibacterial agents. This approach is relatively inexpensive, with minimal resource requirements. This technique consists of spotting supernatant from a donor strain (potentially harboring a toxic compound(s)) onto a solidified soft agar overlay that is seeded with a bacterial test strain (potentially sensitive to the toxic compound(s)). We utilized this technique to screen a library of Pseudomonas syringae strains for intraspecific killing. By combining this approach with a precipitation step and targeted gene deletions, multiple toxic compounds produced by the same strain can be differentiated. The two antagonistic agents commonly recovered using this technique are bacteriophages and bacteriocins. These two agents can be differentiated using two simple additional tests. Performing a serial dilution on a supernatant containing bacteriophage will result in individual plaques becoming less in number with greater dilution, whereas serial dilution of a supernatant containing bacteriocin will result a clearing zone that becomes uniformly more turbid with greater dilution. Additionally, a bacteriophage will produce a clearing zone when spotted onto a fresh soft agar overlay seeded with the same strain, whereas a bacteriocin will not produce a clearing zone when transferred to a fresh soft agar lawn, owing to the dilution of the bacteriocin.

  5. Influence of different Mueller-Hinton agars and media age on Etest susceptibility testing of tigecycline.

    PubMed

    Tan, Thean Yen; Ng, Lily Siew Yong; Chen, Dorene Mei Mei

    2010-09-01

    This study investigated the effect of different Mueller-Hinton agars and media age on tigecycline MICs, obtained by Etest. Variations in MIC values on different Mueller-Hinton were noted, which may result in changes in categoric susceptibility. The use of stored Mueller-Hinton media had minimal effect on MIC values.

  6. Improvement of mannitol lysine crystal violet brilliant green agar for the selective isolation of H2S-positive Salmonella.

    PubMed

    Kodaka, H; Mizuochi, S; Honda, T; Yamaguchi, K

    2000-12-01

    Mannitol lysine crystal violet brilliant green agar (MLCB) is widely used in Japan for Salmonella isolation because the medium has been commercially available. Colonies of Salmonella on MLCB appear colorless with black centers due to H2S gas production; however, most Citrobacter freundii also produce H2S gas. In order to distinguish H2S-positive Salmonella from C. freundii we have improved MLCB. To MLCB was added 1% lactose (L-MLCB). The relation for pH and black center colony formation was examined. The pH of MLCB and L-MLCB inoculated with Salmonella species was slightly acid after 7 h, but the pH of L-MLCB inoculated with C. freundii did not become acid for 24 h. The colony of C. freundii did not have a black center because the production of acid from lactose lowers the pH below 10 where it is needed for H2S to react with iron to produce black pigments. Of 99 Salmonella strains including 13 serotypes tested, all strains had the same colony morphologies on MLCB and L-MLCB. When MLCB and L-MLCB were evaluated with 36 C. freundii strains isolated from foods, only colonies on MLCB had black centers. We conclude that L-MLCB is useful for detection of nonlactose-fermenting, H2S-positive Salmonella in food samples.

  7. Combined Use of Pastorex Staph-Plus and Either of Two New Chromogenic Agars, MRSA ID and CHROMagar MRSA, for Detection of Methicillin-Resistant Staphylococcus aureus▿

    PubMed Central

    Compernolle, Veerle; Verschraegen, Gerda; Claeys, Geert

    2007-01-01

    We describe the search toward a fast and reliable strategy to detect and confirm the presence of methicillin-resistant Staphylococcus aureus (MRSA) in screening samples. First, we evaluated the sensitivities and specificities of oxacillin resistance screening agar (ORSA) with enrichment (tryptic soy broth [TSB] and ORSA [TSB-ORSA]) and without enrichment (ORSA), MRSA ID (MRSA_ID) plates, and CHROMagar MRSA (C_MRSA) plates, all of which were inoculated with equal volumes of a suspension made by emulsifying screening swabs. Whereas the sensitivities after 48 h were similar for all media tested (77% for MRSA_ID and ORSA; 73% for C_MRSA and ORSA after enrichment [TSB-ORSA]), the specificities of MRSA_ID (98% after 24 h and 94% after 48 h) and C_MRSA (98% after 24 h and 90% after 48 h) were superior to the specificities of ORSAs (92% after 24 h and 83% after 48 h) and TSB-ORSA (86% after 24 h and 81% after 48 h). Subsequently, the performance of the Pastorex Staph-Plus agglutination test with presumptive MRSA isolates taken directly from chromogenic agars (direct_Pastorex agglutination) was compared to that of the Pastorex Staph-Plus agglutination test with isolates from blood agar subcultures (conventional_Pastorex agglutination). When the direct_Pastorex agglutination test on MRSA_ID plates was combined with Gram staining, the direct_Pastorex agglutination test with samples from MRSA_ID plates was as reliable as the conventional_Pastorex agglutination test with samples from blood agar subcultures from MRSA_ID plates. In contrast, the direct_Pastorex agglutination test with samples from C_MRSA plates gave false-negative results. Finally, we calculated the processing times of the four different strategies, namely, (i) enrichment in TSB supplemented with NaCl, subsequent culture on ORSA, and the conventional_Pastorex agglutination test; (ii) direct inoculation of ORSA combined with conventional_Pastorex agglutination test; (iii) direct inoculation of MRSA_ID plates

  8. Micro-agar salt bridge in patch-clamp electrode holder stabilizes electrode potentials

    PubMed Central

    Shao, Xuesi M.; Feldman, Jack L.

    2015-01-01

    Maintaining a stable electrode potential is critical for patch-clamp measurements. The electrode potential of conventional patch electrode-holder assembly, where an Ag/AgCl wire is in direct contact with the patch pipette filling solution, is subject to drift if the pipette solution contains a low concentration of chloride ions (Cl−). We developed an agar bridge of 3 M KCl filled in a polyimide microtubing which forms an electrical connection between an Ag/AgCl wire and the pipette solution. We examined the offset potentials of the micro-agar salt bridge electrode assembly in parallel with a conventional electrode assembly in generic recording conditions (the pipette solution contained 5 mM NaCl). The junction potential between the Ag/AgCl wire and the pipette filling solution in the conventional electrode contributed to most of the offset potential drift observed during the course of 30 min recordings. The drift was up to 27.3 mV after several changes of the glass pipette. In contrast, the micro-agar salt bridge stabilized the electrode potential within typically 2 mV without affecting the patch electrode resistance, capacitance or noise level. Numerical simulations showed that Cl− diffusion from the agar bridge to the tip caused a negligible 0.4 μM Cl− concentration change at the pipette tip within 30 min. This method is easy to implement and provides long-term recording stability. The micro-agar salt bridge can fit in most commercial patch electrode holders and can be conveniently maintained. PMID:16916545

  9. Interplanetary medium data book. Supplement 3: 1977-1985

    NASA Technical Reports Server (NTRS)

    Couzens, David A.; King, Joseph H.

    1986-01-01

    The updating of the hourly resolution, near-Earth solar wind data compilation is discussed. Data plots and listings are then presented. In the text, the time shifting of ISEE 3 fine-scale magnetic field and and plasma data, using corotation delay, and the normalization of IMP-MIT and ISEE densities and temperatures to equivalent IMP-LANL values, are discussed in detail. The levels of arbitrariness in combining data sets, and of random differences between data sets, are elucidated.

  10. Differentiating non-0157:H7 STEC serogroups from ground beef plated on agar media by hyperspetral imaging

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: The development of an assay to detect and confirm a positive non-O157:H7 isolate is challenging when mixed morphologically results are obtained from the serogroups growing on Rainbow agar. Rainbow agar is only claimed by the manufacturer to be very specific for E.coli O157:H7 strain...

  11. Effect of lignin on water vapor barrier, mechanical, and structural properties of agar/lignin composite films.

    PubMed

    Shankar, Shiv; Reddy, Jeevan Prasad; Rhim, Jong-Whan

    2015-11-01

    Biodegradable composite films were prepared using two renewable resources based biopolymers, agar and lignin alkali. The lignin was used as a reinforcing material and agar as a biopolymer matrix. The effect of lignin concentration (1, 3, 5, and 10wt%) on the performance of the composite films was studied. In addition, the mechanical, water vapor barrier, UV light barrier properties, FE-SEM, and TGA of the films were analyzed. The agar/lignin films exhibited higher mechanical and UV barrier properties along with lower water vapor permeability compared to the neat agar film. The FTIR and SEM results showed the compatibility of lignin with agar polymer. The swelling ratio and moisture content of agar/lignin composite films were decreased with increase in lignin content. The thermostability and char content of agar/lignin composite films increased with increased lignin content. The results suggested that agar/lignin films have a potential to be used as a UV barrier food packaging material for maintaining food safety and extending the shelf-life of the packaged food.

  12. Monensin-based medium for determination of total gram-negative bacteria and Escherichia coli.

    PubMed Central

    Petzel, J P; Hartman, P A

    1985-01-01

    Plate count-monensin-KCl (PMK) agar, for enumeration of both gram-negative bacteria and Escherichia coli, is composed of (per liter) 23.5 g of plate count agar, 35 mg of monensin, 7.5 g of KCl, and 75 mg of 4-methylumbelliferyl-beta-D-glucuronide (MUG). Monensin was added after the medium was sterilized. The diluent of choice for use with PMK agar was 0.1% peptone (pH 6.8); other diluents were unsatisfactory. Gram-negative bacteria (selected for by the ionophore monensin) can be used to judge the general quality or sanitary history of a commodity. E. coli (differentiated by its ability to hydrolyze the fluorogenic compound MUG) can be used to assess the safety of a commodity in regard to the possible presence of enteric pathogens. Pure-culture studies demonstrated that monensin completely inhibited gram-positive bacteria and had little or no effect on gram-negative bacteria. When gram-negative bacteria were injured by one of several methods, a few species (including E. coli) became sensitive to monensin; this sensitivity was completely reversed in most instances by the inclusion of KCl in the medium. When PMK agar was tested with food and environmental samples, 96% of 535 isolates were gram negative; approximately 68% of colonies from nonselective medium were gram negative. PMK agar was more selective than two other media against gram-positive bacteria and was less inhibitory for gram-negative bacteria. However, with water samples, KCl had an inhibitory effect on gram-negative bacteria, and it should therefore be deleted from monensin-containing medium for water analysis.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3890742

  13. [Evaluation of the Yersinia enterocolitica pathogenicity through some phenotypic and genotypic characters: CRMOX agar positivity and presence of the ail gene].

    PubMed

    Sacco, C; Ciapini, A; Santomauro, F; Dei, R; Donato, R

    2005-01-01

    Sixty-nine strains of Y. enterocolitica isolated from environmental and human matrices (waste water, food and faeces) were studied in order to evidence the presence of ail gene, calcium-dependency and Congo Red absorption for pathogenic strains identification. Out of 24 clinical strains, the ail gene was present in 21 (87%), among which 79% were CRMOX-positive as well. On the contrary, none of the 45 environmental strains showed the ail gene although only one (isolated from cooked vegetables) was CRMOX agar positive. Our results confirmed the importance of molecular methods to evidence the Y. enterocolitica pathogenic strains. However, our study pointed also the utility to consider the approach of classic bacteriology, like the subcoltivation on CRMOX agar to show calcium-dependency and Congo Red absorption. In particular, when dealing with environmental isolates, that medium will be useful as a preliminary screening to identify those isolates which need further research to indicate their pathogenic potential by the use of more complex but also more expensive molecular methods.

  14. Agar Sediment Test for Assessing the Suitability of Organic Waste Streams for Recovering Nutrients by the Aquatic Worm Lumbriculus variegatus

    PubMed Central

    Laarhoven, Bob; Elissen, H. J. H.; Temmink, H.; Buisman, C. J. N.

    2016-01-01

    An agar sediment test was developed to evaluate the suitability of organic waste streams from the food industry for recovering nutrients by the aquatic worm Lumbriculus variegatus (Lv). The effects of agar gel, sand, and food quantities in the sediment test on worm growth, reproduction, and water quality were studied. Agar gel addition ameliorated growth conditions by reducing food hydrolysis and altering sediment structure. Best results for combined reproduction and growth were obtained with 0.6% agar-gel (20 ml), 10 g. fine sand, 40 g. coarse sand, and 105 mg fish food (Tetramin). With agar gel, ingestion and growth is more the result of addition of food in its original quality. Final tests with secondary potato starch sludge and wheat bran demonstrated that this test is appropriate for the comparison of solid feedstuffs and suspended organic waste streams. This test method is expected to be suitable for organic waste studies using other sediment dwelling invertebrates. PMID:26937632

  15. Agar Sediment Test for Assessing the Suitability of Organic Waste Streams for Recovering Nutrients by the Aquatic Worm Lumbriculus variegatus.

    PubMed

    Laarhoven, Bob; Elissen, H J H; Temmink, H; Buisman, C J N

    2016-01-01

    An agar sediment test was developed to evaluate the suitability of organic waste streams from the food industry for recovering nutrients by the aquatic worm Lumbriculus variegatus (Lv). The effects of agar gel, sand, and food quantities in the sediment test on worm growth, reproduction, and water quality were studied. Agar gel addition ameliorated growth conditions by reducing food hydrolysis and altering sediment structure. Best results for combined reproduction and growth were obtained with 0.6% agar-gel (20 ml), 10 g. fine sand, 40 g. coarse sand, and 105 mg fish food (Tetramin). With agar gel, ingestion and growth is more the result of addition of food in its original quality. Final tests with secondary potato starch sludge and wheat bran demonstrated that this test is appropriate for the comparison of solid feedstuffs and suspended organic waste streams. This test method is expected to be suitable for organic waste studies using other sediment dwelling invertebrates.

  16. Crystallization of brushite from EDTA-chelated calcium in agar gels

    NASA Astrophysics Data System (ADS)

    Plovnick, Ross H.

    1991-10-01

    Brushite (dicalcium phosphate dihydrate, CaHPO 4·2H 2O, DCPD) has been crystallized from ethylenediaminetetraacetic acid (EDTA)-chelated calcium in agar gels at initial pH 4.5-6.4 and Ca/P molar ratio above about 0.8. White, spherular crystalline DCPD aggregates up to 1 mm in diameter grew in 8-10 weeks. Liesegang ring were occassionally observed at initial gel pH 5 and Ca/P molar ratio near 1. Crystals were characterized by X-ray diffraction analysis, scanning electron microscopy, and infrared absorption spectroscopy. Brushite crystals were also grown in agar gels with either unchelated Ca initially present in the gels and EDTA in overlying solutions, or EDTA initially present in the gels and unchelated Ca in overlying solutions. These crystals grew as 2-3 mm aggregates mainly within 1-3 cm of the gel-solution interface.

  17. [Physical properties of the agar of Gracilariopsis tenuifrons (Gracilariacea) from Sucre, Venezuela].

    PubMed

    Zecchinel, E; Brito, L; Lárez, G

    2000-12-01

    The yield, gel strength, gelling and melting temperatures of Gracilariopsis tenuifrons agar from Guayacán, Araya Peninsula, Sucre State, Venezuela were determined. Yield values with and without alkali treatment ranged from 23.22 to 39.57% and from 16.29 to 22.42% respectively, while gel strength with alkali treatment fluctuated betwen 699.31 and 1231.69 g/cm2 and without treatment varied from 278.0 to 691.06 g/cm2. Gelling and melting temperatures were in the range reported for other agarophytes. Considering gel strength, the agar quality of G. tenuifrons was higher than in other species and its exploitation in economically feasible.

  18. Modification of the Congo red agar method to detect biofilm production by Staphylococcus epidermidis.

    PubMed

    Kaiser, Thaís Dias Lemos; Pereira, Eliezer Menezes; Dos Santos, Kátia Regina Netto; Maciel, Ethel Leonor Noia; Schuenck, Ricardo Pinto; Nunes, Ana Paula Ferreira

    2013-03-01

    Staphylococcus epidermidis in immunocompromised patients can cause bacteremia related to the use of catheter due to biofilm production. There are different phenotypic methods to detect biofilm formation. One method is based on culture in brain heart infusion agar (BHIA) containing sucrose and red Congo dye (original Congo red agar). Our group created a new CRA formula and we have confirmed its capacity to detect biofilm production in 210 S. epidermidis strains, including 76 (36.2%) icaAB gene-positive strains. Other parameters were also evaluated. The new CRA formula that gave the best results was BHIA with sucrose (5%), Congo red (0.08%), NaCl (1.5%), glucose (2%), and vancomycin (0.5 mg/mL) (vancomycin-modified CRA-CRAmod). The CRAmod plus vancomycin may be a promising tool and can help to determine the real participation of S. epidermidis in the infectious process.

  19. Tentative inhibition zone criteria (Bauer-Kirby agar disk diffusion method) for rifampin against staphylococci.

    PubMed

    Traub, W H; Spohr, M; Bauer, D

    1987-01-01

    Two of 359 (0.6%) clinical isolates of Staphylococcus aureus and 12 of 218 (5.5%) clinical isolates of coagulase-negative staphylococci were resistant or of intermediate susceptibility against rifampin as based on minimal inhibitory concentration (MIC) breakpoints obtained with the agar dilution method: MIC greater than or equal to 2 micrograms/ml = resistant; MIC 0.25-1 microgram/ml = intermediate susceptible; MIC less than 0.125 microgram/ml = susceptible. The following inhibition zone criteria with 2 micrograms rifampin disks were proposed for staphylococcal isolates utilizing the Bauer-Kirby agar disk diffusion test: diameter of inhibition zones less than or equal to 13 mm = resistant; diameter 14-21 mm = intermediate susceptible; diameter greater than or equal to 22 mm = susceptible.

  20. Emerging Supplements in Sports

    PubMed Central

    Mason, Bryan C.; Lavallee, Mark E.

    2012-01-01

    Context: Nutritional supplements advertised as ergogenic are commonly used by athletes at all levels. Health care professionals have an opportunity and responsibility to counsel athletes concerning the safety and efficacy of supplements on the market. Evidence Acquisition: An Internet search of common fitness and bodybuilding sites was performed to identify supplement promotions. A search of MEDLINE (2000–August, 2011) was performed using the most commonly identified supplements, including glutamine, choline, methoxyisoflavone, quercetin, zinc/magnesium aspartate, and nitric oxide. The search terms supplement, ergogenic aid, and performance were also used. Results: Six common and newer supplements were identified, including glutamine, choline, methoxyisoflavone, quercetin, zinc/magnesium aspartate, and nitric oxide. Conclusions: Controlled studies have not determined the effects of these supplements on performance in athletes. Scientific evidence is not available to support the use of these supplements for performance enhancement. PMID:23016081

  1. Enhancing Bioaerosol Sampling by Andersen Impactors Using Mineral-Oil-Spread Agar Plate

    PubMed Central

    Xu, Zhenqiang; Wei, Kai; Wu, Yan; Shen, Fangxia; Chen, Qi; Li, Mingzhen; Yao, Maosheng

    2013-01-01

    As a bioaerosol sampling standard, Andersen type impactor is widely used since its invention in 1950s, including the investigation of the anthrax attacks in the United States in 2001. However, its related problems such as impaction and desiccation stress as well as particle bounce have not been solved. Here, we improved its biological collection efficiencies by plating a mineral oil layer (100 µL) onto the agar plate. An Andersen six-stage sampler and a BioStage impactor were tested with mineral-oil-spread agar plates in collecting indoor and outdoor bacterial and fungal aerosols. The effects of sampling times (5, 10 and 20 min) were also studied using the BioStage impactor when sampling environmental bioaerosols as well as aerosolized Bacillus subtilis (G+) and Escherichia coli (G-). In addition, particle bounce reduction by mineral-oil-plate was also investigated using an optical particle counter (OPC). Experimental results revealed that use of mineral-oil-spread agar plate can substantially enhance culturable bioaerosol recoveries by Andersen type impactors (p-values<0.05). The recovery enhancement was shown to depend on bioaerosol size, type, sampling time and environment. In general, more enhancements (extra 20%) were observed for last stage of the Andersen six-stage samplers compared to the BioStage impactor for 10 min sampling. When sampling aerosolized B. subtilis, E. coli and environmental aerosols, the enhancement was shown to increase with increasing sampling time, ranging from 50% increase at 5 min to ∼100% at 20 min. OPC results indicated that use of mineral oil can effectively reduce the particle bounce with an average of 66% for 10 min sampling. Our work suggests that enhancements for fungal aerosols were primarily attributed to the reduced impaction stress, while for bacterial aerosols reduced impaction, desiccation and particle bounce played major roles. The developed technology can readily enhance the agar-based techniques including those high

  2. Draft genome of agar-degrading marine bacterium Gilvimarinus agarilyticus JEA5.

    PubMed

    Lee, Youngdeuk; Lee, Su-Jin; Park, Gun-Hoo; Heo, Soo-Jin; Umasuthan, Navaneethaiyer; Kang, Do-Hyung; Oh, Chulhong

    2015-06-01

    Gilvimarinus agarilyticus JEA5, which effectively degrades agar, was isolated from the seawater of Jeju Island, Republic of Korea. Here, we report the draft genome sequence of G. agarilyticus JEA5 with a total genome size of 4,179,438bp from 2 scaffolds (21 contigs) with 53.15% G+C content. Various polysaccharidases including 11 predicted agarases were observed from the draft genome of G. agarilyticus JEA5.

  3. Enhancing bioaerosol sampling by Andersen impactors using mineral-oil-spread agar plate.

    PubMed

    Xu, Zhenqiang; Wei, Kai; Wu, Yan; Shen, Fangxia; Chen, Qi; Li, Mingzhen; Yao, Maosheng

    2013-01-01

    As a bioaerosol sampling standard, Andersen type impactor is widely used since its invention in 1950s, including the investigation of the anthrax attacks in the United States in 2001. However, its related problems such as impaction and desiccation stress as well as particle bounce have not been solved. Here, we improved its biological collection efficiencies by plating a mineral oil layer (100 µL) onto the agar plate. An Andersen six-stage sampler and a BioStage impactor were tested with mineral-oil-spread agar plates in collecting indoor and outdoor bacterial and fungal aerosols. The effects of sampling times (5, 10 and 20 min) were also studied using the BioStage impactor when sampling environmental bioaerosols as well as aerosolized Bacillus subtilis (G+) and Escherichia coli (G-). In addition, particle bounce reduction by mineral-oil-plate was also investigated using an optical particle counter (OPC). Experimental results revealed that use of mineral-oil-spread agar plate can substantially enhance culturable bioaerosol recoveries by Andersen type impactors (p-values<0.05). The recovery enhancement was shown to depend on bioaerosol size, type, sampling time and environment. In general, more enhancements (extra 20%) were observed for last stage of the Andersen six-stage samplers compared to the BioStage impactor for 10 min sampling. When sampling aerosolized B. subtilis, E. coli and environmental aerosols, the enhancement was shown to increase with increasing sampling time, ranging from 50% increase at 5 min to ∼100% at 20 min. OPC results indicated that use of mineral oil can effectively reduce the particle bounce with an average of 66% for 10 min sampling. Our work suggests that enhancements for fungal aerosols were primarily attributed to the reduced impaction stress, while for bacterial aerosols reduced impaction, desiccation and particle bounce played major roles. The developed technology can readily enhance the agar-based techniques including those high

  4. [Evaluation of chromogenic medium Uriselect4 in urine culture].

    PubMed

    Ferjani, Asma; Marzouk, Manel; Idriss, Nadia; Sammoud, Sammoud; Hannachi, Naila; Boukadida, Janel

    2011-01-01

    We evaluated the performance and the cost of chromogenic medium Uriselect4 agar with regard to the standard medium for the detection and identification of urinary tract pathogens. A total of 503 clinical urine specimens containing leucocytes greater or equal to 104/mL were analysed prospectively, in parallel by two different persons on blood agar (GS) and Uriselect4 according to the manufacturers' instructions. Of the 503 urine specimens tested, 210 gave a positive culture on Uriselect4 versus 181 on GS. The majority of bacterial species grew on both media; enterobacteria grew on Uriselect4 better than GS. The identification of Escherichia coli (E. coli), Proteus mirabilis (P. mirabilis), KES group and Enterococcus faecalis (E. faecalis) did not require the use of galleries Api and has a gain of 24  h. Positive pure cultures on Uriselect4 corresponding to negative cultures of GS were noted in 17 ases. Conversely, in seven cases a positive pure culture on GS was noted while the corresponding Uriselect4 cultures were negative. The cost of identification on GS (including the cost of galleries Api), was about two times higher than Uriselect4. Uriselect4 medium isolates the most frequent urinary tract pathogens and identify them so almost immediately, with a lower cost.

  5. Selection of brain metastasis-initiating breast cancer cells determined by growth on hard agar.

    PubMed

    Guo, Lixia; Fan, Dominic; Zhang, Fahao; Price, Janet E; Lee, Ju-Seog; Marchetti, Dario; Fidler, Isaiah J; Langley, Robert R

    2011-05-01

    An approach that facilitates rapid isolation and characterization of tumor cells with enhanced metastatic potential is highly desirable. Here, we demonstrate that plating GI-101A human breast cancer cells on hard (0.9%) agar selects for the subpopulation of metastasis-initiating cells. The agar-selected cells, designated GI-AGR, were homogeneous for CD44(+) and CD133(+) and five times more invasive than the parental GI-101A cells. Moreover, mice injected with GI-AGR cells had significantly more experimental brain metastases and shorter overall survival than did mice injected with GI-101A cells. Comparative gene expression analysis revealed that GI-AGR cells were markedly distinct from the parental cells but shared an overlapping pattern of gene expression with the GI-101A subline GI-BRN, which was generated by repeated in vivo recycling of GI-101A cells in an experimental brain metastasis model. Data mining on 216 genes shared between GI-AGR and GI-BRN breast cancer cells suggested that the molecular phenotype of these cells is consistent with that of cancer stem cells and the aggressive basal subtype of breast cancer. Collectively, these results demonstrate that analysis of cell growth in a hard agar assay is a powerful tool for selecting metastasis-initiating cells in a heterogeneous population of breast cancer cells, and that such selected cells have properties similar to those of tumor cells that are selected based on their potential to form metastases in mice.

  6. Ultrasound induced bubble clusters and tunnels in tissue-mimicking agar phantoms

    NASA Astrophysics Data System (ADS)

    Movahed, Pooya; Kreider, Wayne; Maxwell, Adam D.; Bailey, Michael R.; Freund, Jonathan B.

    2016-11-01

    Soft tissue fractionation induced by acoustic cavitation is desired for non-invasive tissue removal in histotripsy, while being a potential injury mechanism in other therapeutic ultrasound treatments such as lithotripsy. In this work, we investigate the formation of bubble clusters and tunnels in tissue-mimicking agar phantoms by focused ultrasound bursts to inform a class of damage models. Agar phantoms of different stiffness were subjected to a series of multi-cycle ultrasound bursts, using a burst wave lithotripsy (BWL) protocol, and simultaneously imaged at 200 frames per second (1 image per ultrasound burst). Some bubbles become visible in images ( 200 microns) due to the negative pressure ( 7.5 MPa) in the initial bursts, and the number of visible bubbles increases continuously during the subsequent bursts. A Rayleigh-Plesset-type bubble dynamics model, which accounts for viscoelastic confinement of agar gels, is developed. Material fatigue leading to eventual irreversible fracture-like failure in this model is proposed to explain the key observations. In addition to isolated, approximately spherical bubbles, long tunnel-like features are observed, which are seemingly lines of joined bubbles along a possible fracture or defect. The geometry of these tunnel-like features is quantified, and a physical explanation for tunnel formation is proposed in terms of bubble expansion and unstable collapse. This work was supported by NIH NIDDK Grant P01-DK043881.

  7. Predicting the growth situation of Pseudomonas aeruginosa on agar plates and meat stuffs using gas sensors

    NASA Astrophysics Data System (ADS)

    Gu, Xinzhe; Sun, Ye; Tu, Kang; Dong, Qingli; Pan, Leiqing

    2016-12-01

    A rapid method of predicting the growing situation of Pseudomonas aeruginosa is presented. Gas sensors were used to acquire volatile compounds generated by P. aeruginosa on agar plates and meat stuffs. Then, optimal sensors were selected to simulate P. aeruginosa growth using modified Logistic and Gompertz equations by odor changes. The results showed that the responses of S8 or S10 yielded high coefficients of determination (R2) of 0.89–0.99 and low root mean square errors (RMSE) of 0.06–0.17 for P. aeruginosa growth, fitting the models on the agar plate. The responses of S9, S4 and the first principal component of 10 sensors fit well with the growth of P. aeruginosa inoculated in meat stored at 4 °C and 20 °C, with R2 of 0.73–0.96 and RMSE of 0.25–1.38. The correlation coefficients between the fitting models, as measured by electronic nose responses, and the colony counts of P. aeruginosa were high, ranging from 0.882 to 0.996 for both plate and meat samples. Also, gas chromatography–mass spectrometry results indicated the presence of specific volatiles of P. aeruginosa on agar plates. This work demonstrated an acceptable feasibility of using gas sensors—a rapid, easy and nondestructive method for predicting P. aeruginosa growth.

  8. The use of agar as a novel filler for monolithic matrices produced using hot melt extrusion.

    PubMed

    Lyons, John G; Devine, Declan M; Kennedy, James E; Geever, Luke M; O'Sullivan, Patrick; Higginbotham, Clement L

    2006-08-01

    The use of filler materials in an extended release monolithic polymer matrix can lead to a vastly altered release profile for the active pharmaceutical ingredient. A range of excipients for use in monolithic matrices have been discussed in the literature. The body of work described in this research paper outlines the use of agar as a novel filler material in a hot melt extruded polymer matrix. Several batches of matrix material were prepared with Diclofenac sodium used as the active pharmaceutical ingredient (API). Agar and microcrystalline cellulose were used as the filler materials in varying ratios, to examine the effect of % filler content as well as filler type on the properties of the hot melt extruded matrix. The resultant extrudates were characterised using steady state parallel plate rheometry, differential scanning calorimetry (DSC) and dissolution testing. The rheometry analysis concluded that the fillers used resulted in an increase in the matrix viscosity. The DSC scans obtained showed negligible effects on the melting behavior of the matrix as a result of the filler inclusion. Dissolution analysis showed that the presence of the fillers resulted in a slower release rate of API than for the matrix alone. The results detailed within this paper indicate that agar is a viable filler for extended release hot melt produced dosage forms.

  9. Isolation and characterization of agar-degrading endophytic bacteria from plants.

    PubMed

    Song, Tao; Zhang, Weijia; Wei, Congchong; Jiang, Tengfei; Xu, Hui; Cao, Yi; Cao, Yu; Qiao, Dairong

    2015-02-01

    Agar is a polysaccharide extracted from the cell walls of some macro-algaes. Among the reported agarases, most of them come from marine environment. In order to better understand different sources of agarases, it is important to search new non-marine native ones. In this study, seven agar-degrading bacteria were first isolated from the tissues of plants, belonging to three genera, i.e., Paenibacillus sp., Pseudomonas sp., and Klebsiella sp. Among them, the genus Klebsiella was first reported to have agarolytic ability and the genus Pseudomonas was first isolated from non-marine environment with agarase activity. Besides, seven strains were characterized by investigating the growth and agarase production in the presence of various polysaccharides. The results showed that they could grow on several polysaccharides such as araban, carrageenan, chitin, starch, and xylan. Besides, they could also produce agarase in the presence of different polysaccharides other than agar. Extracellular agarases from seven strains were further analyzed by SDS-PAGE combined with activity staining and estimated to be 75 kDa which has great difference from most reported agarases.

  10. Simulation of Bacillus subtilis biofilm growth on agar plate by diffusion-reaction based continuum model

    NASA Astrophysics Data System (ADS)

    Zhang, Xianlong; Wang, Xiaoling; Nie, Kai; Li, Mingpeng; Sun, Qingping

    2016-08-01

    Various species of bacteria form highly organized spatially-structured aggregates known as biofilms. To understand how microenvironments impact biofilm growth dynamics, we propose a diffusion-reaction continuum model to simulate the formation of Bacillus subtilis biofilm on an agar plate. The extended finite element method combined with level set method are employed to perform the simulation, numerical results show the quantitative relationship between colony morphologies and nutrient depletion over time. Considering that the production of polysaccharide in wild-type cells may enhance biofilm spreading on the agar plate, we inoculate mutant colony incapable of producing polysaccharide to verify our results. Predictions of the glutamate source biofilm’s shape parameters agree with the experimental mutant colony better than that of glycerol source biofilm, suggesting that glutamate is rate limiting nutrient for Bacillus subtilis biofilm growth on agar plate, and the diffusion-limited is a better description to the experiment. In addition, we find that the diffusion time scale is of the same magnitude as growth process, and the common-employed quasi-steady approximation is not applicable here.

  11. Predicting the growth situation of Pseudomonas aeruginosa on agar plates and meat stuffs using gas sensors

    PubMed Central

    Gu, Xinzhe; Sun, Ye; Tu, Kang; Dong, Qingli; Pan, Leiqing

    2016-01-01

    A rapid method of predicting the growing situation of Pseudomonas aeruginosa is presented. Gas sensors were used to acquire volatile compounds generated by P. aeruginosa on agar plates and meat stuffs. Then, optimal sensors were selected to simulate P. aeruginosa growth using modified Logistic and Gompertz equations by odor changes. The results showed that the responses of S8 or S10 yielded high coefficients of determination (R2) of 0.89–0.99 and low root mean square errors (RMSE) of 0.06–0.17 for P. aeruginosa growth, fitting the models on the agar plate. The responses of S9, S4 and the first principal component of 10 sensors fit well with the growth of P. aeruginosa inoculated in meat stored at 4 °C and 20 °C, with R2 of 0.73–0.96 and RMSE of 0.25–1.38. The correlation coefficients between the fitting models, as measured by electronic nose responses, and the colony counts of P. aeruginosa were high, ranging from 0.882 to 0.996 for both plate and meat samples. Also, gas chromatography–mass spectrometry results indicated the presence of specific volatiles of P. aeruginosa on agar plates. This work demonstrated an acceptable feasibility of using gas sensors—a rapid, easy and nondestructive method for predicting P. aeruginosa growth. PMID:27941841

  12. Performance of Candida ID, a New Chromogenic Medium for Presumptive Identification of Candida Species, in Comparison to CHROMagar Candida

    PubMed Central

    Willinger, Birgit; Hillowoth, Cornelia; Selitsch, Brigitte; Manafi, Mammad

    2001-01-01

    Candida ID agar allows identification of Candida albicans and differentiation of other Candida species. In comparison with CHROMagar Candida, we evaluated the performance of this medium directly from 596 clinical specimens. In particular, detection of C. albicans after 24 h of incubation was easier on Candida ID (sensitivity, 96.8%) than on CHROMagar (sensitivity, 49.6%). PMID:11574621

  13. Comparison of performance of the novel chromogenic spectra VRE agar to that of bile esculin azide and Campylobacter agars for detection of vancomycin-resistant enterococci in fecal samples.

    PubMed

    Jenkins, S G; Raskoshina, L; Schuetz, A N

    2011-11-01

    A total of 142 stool specimens were evaluated for vancomycin-resistant enterococcus (VRE). Twenty-four-hour sensitivities and specificities, respectively, were 98% and 95% for Spectra VRE chromogenic agar (Remel, Lenexa, KS), 86% and 92% for bile esculin azide with vancomycin (BEAV; Remel), and 96.5% and 92% for Campylobacter agar (CAMPY; Remel). Spectra VRE and CAMPY are significantly more sensitive at 24 h than BEAV.

  14. Synthetic laser medium

    DOEpatents

    Stokowski, S.E.

    1987-10-20

    A laser medium is particularly useful in high average power solid state lasers. The laser medium includes a chromium dopant and preferably neodymium ions as codopant, and is primarily a gadolinium scandium gallium garnet, or an analog thereof. Divalent cations inhibit spiral morphology as large boules from which the laser medium is derived are grown, and a source of ions convertible between a trivalent state and a tetravalent state at a low ionization energy are in the laser medium to reduce an absorption coefficient at about one micron wavelength otherwise caused by the divalent cations. These divalent cations and convertible ions are dispersed in the laser medium. Preferred convertible ions are provided from titanium or cerium sources.

  15. Synthetic laser medium

    DOEpatents

    Stokowski, Stanley E.

    1989-01-01

    A laser medium is particularly useful in high average power solid state lasers. The laser medium includes a chormium dopant and preferably neodymium ions as codopant, and is primarily a gadolinium scandium gallium garnet, or an analog thereof. Divalent cations inhibit spiral morphology as large boules from which the laser medium is derived are grown, and a source of ions convertible between a trivalent state and a tetravalent state at a low ionization energy are in the laser medium to reduce an absorption coefficient at about one micron wavelength otherwise caused by the divalent cations. These divalent cations and convertible ions are dispersed in the laser medium. Preferred convertible ions are provided from titanium or cerium sources.

  16. Evaluation of a new agar in Uricult-Trio for rapid detection of Escherichia coli in urine.

    PubMed Central

    Dalet, F; Segovia, T

    1995-01-01

    A new commercial agar (Uricult-Trio) with 8-hydroxyquinoline-beta-glucuronide was used to assess 2,536 uropathogens for beta-glucuronidase activity typical of Escherichia coli. Included in the study were 1,807 strains of the family Enterobacteriaceae, 284 strains of nonfermentative bacilli, 345 strains of gram-positive cocci, and 100 yeast strains. In identifying E. coli, the test agar gave a sensitivity of 95.5% and a specificity of 97.2%. Fifty E. coli isolates gave negative reactions; 31 non-E. coli strains produced black colonies characteristic of E. coli. No growth of gram-positive cocci and no false-positive reactions from yeasts were observed. The recovery rate for E. coli on this agar was at least 10% higher than that on blood agar. PMID:7615766

  17. Antiserum-agar plate method for simultaneous detection and direct isolation of Legionella species in clinical and environmental specimens.

    PubMed Central

    Janssen, W A; Hedlund, K W

    1982-01-01

    Colonies of Legionella pneumophila serotypes 1 through 6, L. micdadei, L. bozemanii, L. dumoffii, and L. gormanii, which were developed on filtered yeast extract agar containing polyvalent antiserum, were surrounded by distinct, specific precipitin rings. Images PMID:7050153

  18. Prospective Two-Center Comparison of Three Chromogenic Agars for Methicillin-Resistant Staphylococcus aureus Screening in Hospitalized Patients

    PubMed Central

    Verhulst, Carlo; Nonhoff, Claire; Nagant, Carole; Denis, Olivier; Kluytmans, Jan

    2015-01-01

    Three chromogenic media, chromID MRSA SMART (SMART), chromID MRSA first generation (chromID), and Brilliance MRSA (OX2), were evaluated for methicillin-resistant Staphylococcus aureus (MRSA) screening using 1,220 samples. The sensitivity at 24 h was significantly better with the SMART agar (66.4%) than that with chromID agar (50.5%). Enrichment and incubation until 48 h are still needed for an optimal yield. PMID:26109446

  19. Trace Amounts of Furan-2-Carboxylic Acids Determine the Quality of Solid Agar Plates for Bacterial Culture

    PubMed Central

    Hara, Shintaro; Isoda, Reika; Tahvanainen, Teemu; Hashidoko, Yasuyuki

    2012-01-01

    Background Many investigators have recognised that a significant proportion of environmental bacteria exist in a viable but non-culturable state on agar plates, and some researchers have also noticed that some of such bacteria clearly recover their growth on matrices other than agar. However, the reason why agar is unsuitable for the growth of some bacteria has not been addressed. Methodology/Principal Findings According to the guide of a bioassay for swarming inhibition, we identified 5-hydroxymethylfuran-2-carboxylic acid (5-HMFA) and furan-2-carboxylic acid (FA) as factors that inhibit bacterial swarming and likely inhibit extracellular polysaccharide production on agar. The furan-2-carboxylic acids 5-HMFA and FA effectively inhibited the swarming and swimming of several environmental bacteria at concentrations of 1.8 and 2.3 µg L−1 (13 and 21 nmol L−1), respectively, which are equivalent to the concentrations of these compounds in 0.3% agar. On Luria-Bertani (LB) plates containing 1.0% agar that had been previously washed with MeOH, a mixture of 5-HMFA and FA in amounts equivalent to their original concentrations in the unwashed agar repressed the swarming of Escherichia coli K12 strain W3110, a representative swarming bacterium. Conclusions/Significance Agar that contains trace amounts of 5-HMFA and FA inhibits the proliferation of some slow-growing or difficult-to-culture bacteria on the plates, but it is useful for single colony isolation due to the ease of identification of swarmable bacteria as the non-swarmed colonies. PMID:22848437

  20. Cavitation-enhanced delivery of insulin in agar and porcine models of human skin

    NASA Astrophysics Data System (ADS)

    Feiszthuber, Helga; Bhatnagar, Sunali; Gyöngy, Miklós; Coussios, Constantin-C.

    2015-03-01

    Ultrasound-assisted transdermal insulin delivery offers a less painful and less invasive alternative to subcutaneous insulin injections. However, ultrasound-based drug delivery, otherwise known as sonophoresis, is a highly variable phenomenon, in part dependent on cavitation. The aim of the current work is to investigate the role of cavitation in transdermal insulin delivery. Fluorescently stained, soluble Actrapid insulin was placed on the surface of human skin-mimicking materials subjected to 265 kHz, 10% duty cycle focused ultrasound. A confocally and coaxially aligned 5 MHz broadband ultrasound transducer was used to detect cavitation. Two different skin models were used. The first model, 3% agar hydrogel, was insonated with a range of pressures (0.25-1.40 MPa peak rarefactional focal pressure—PRFP), with and without cavitation nuclei embedded within the agar at a concentration of 0.05% w/v. The second, porcine skin was insonated at 1.00 and 1.40 MPa PRFP. In both models, fluorescence measurements were used to determine penetration depth and concentration of delivered insulin. Results show that in agar gel, both insulin penetration depth and concentration only increased significantly in the presence of inertial cavitation, with up to a 40% enhancement. In porcine skin the amount of fluorescent insulin was higher in the epidermis of those samples that were exposed to ultrasound compared to the control samples, but there was no significant increase in penetration distance. The results underline the importance of instigating and monitoring inertial cavitation during transdermal insulin delivery.

  1. Cavitation-enhanced delivery of insulin in agar and porcine models of human skin.

    PubMed

    Feiszthuber, Helga; Bhatnagar, Sunali; Gyöngy, Miklós; Coussios, Constantin-C

    2015-03-21

    Ultrasound-assisted transdermal insulin delivery offers a less painful and less invasive alternative to subcutaneous insulin injections. However, ultrasound-based drug delivery, otherwise known as sonophoresis, is a highly variable phenomenon, in part dependent on cavitation. The aim of the current work is to investigate the role of cavitation in transdermal insulin delivery. Fluorescently stained, soluble Actrapid insulin was placed on the surface of human skin-mimicking materials subjected to 265 kHz, 10% duty cycle focused ultrasound. A confocally and coaxially aligned 5 MHz broadband ultrasound transducer was used to detect cavitation. Two different skin models were used. The first model, 3% agar hydrogel, was insonated with a range of pressures (0.25-1.40 MPa peak rarefactional focal pressure-PRFP), with and without cavitation nuclei embedded within the agar at a concentration of 0.05% w/v. The second, porcine skin was insonated at 1.00 and 1.40 MPa PRFP. In both models, fluorescence measurements were used to determine penetration depth and concentration of delivered insulin. Results show that in agar gel, both insulin penetration depth and concentration only increased significantly in the presence of inertial cavitation, with up to a 40% enhancement. In porcine skin the amount of fluorescent insulin was higher in the epidermis of those samples that were exposed to ultrasound compared to the control samples, but there was no significant increase in penetration distance. The results underline the importance of instigating and monitoring inertial cavitation during transdermal insulin delivery.

  2. Coma in the course of severe poisoning after consumption of red fly agaric (Amanita muscaria).

    PubMed

    Mikaszewska-Sokolewicz, Małgorzata A; Pankowska, Sylwestra; Janiak, Marek; Pruszczyk, Piotr; Łazowski, Tomasz; Jankowski, Krzysztof

    2016-01-01

    Red fly agaric poisoning is rare. It can be consumed for suicidal purposes or its psychedelic effect. The paper describes the case of a young men, who fell into a coma after ingestion of the red toadstools. Quick identification of the poison, early use of gastric lavage and symptomatic treatment resulted in regression of symptoms and lead to the patient's discharge from the hospital on the third day after intoxication. Authors discussing the poisonous alkaloids contained in the red toadtools: ibotenic acid, muscimol, muscasone and muscarine and theirs properties, responsible for the symptoms of intoxication.

  3. Comparative study of 6-APA production by free and agar immobilized bacteria in nutrient broth culture.

    PubMed

    Dolui, A K; Das, S

    2011-04-01

    In the present study different bacterial samples were isolated from soil of different places of Dibrugarh and screened for biotransformation ability to produce 6-Aminopenicillanic acid. Among ten isolated bacterial samples, three gram positive bacterial samples designated as AKDD-2, AKDD-4 and AKDD-6 showed the production of 6-APA from penicillin G. Assessment of production of 6-APA after incubation in penicillin G (2 mg/ml) by three different samples separately in free and agar immobilization state was done by HPLC analysis. Reusability of immobilized cells was found successful up to 14 days.

  4. Rapid identification of Candida albicans by using Albicans ID and fluoroplate agar plates.

    PubMed Central

    Rousselle, P; Freydiere, A M; Couillerot, P J; de Montclos, H; Gille, Y

    1994-01-01

    Two commercially available agar media, Albicans ID and Fluoroplate, that use a chromogenic or a fluorogenic substrate for the detection and identification of Candida albicans were evaluated. From 1,006 clinical samples containing 723 yeast strains, 352 C. albicans strains were detected with either of the two media. The sensitivity of each of the two media was 93.8% and the specificity was 98.6%, with five false-positive reactions for Candida tropicalis and no false-negative reactions. PMID:7883894

  5. The Efficiency of UVC Radiation in the Inactivation of
Listeria monocytogenes on Beef-Agar Food Models

    PubMed Central

    James, Christian; James, Stephen

    2015-01-01

    Summary The aim of this study is to evaluate the effect of meat content and surface smoothness on the deactivation of Listeria monocytogenes in beef-agar food models achieved by shortwave ultraviolet (UVC) light. Food models with various meat contents were made using chopped beef slices and agar solution. Prepared models together with a Listeria selective agar (LSA) plate and a slice of cooked beef were inoculated with L. monocytogenes and then exposed to UVC light. Population of Listeria reduced to below the level of detection on the LSA plates. As the content of beef in the beef-agar models increased, more L. monocytogenes cells survived. Survival was greatest on the treated cooked slice of beef. To better understand the effect of surface irregularities, a white light interferometer was used to analyse the surface smoothness of beef-agar media and LSA plates. No correlation was observed between the surface roughness of seven out of nine types of produced beef-agar media and the degree of inactivation resulting from UVC radiation at the given dose, whereas, less bacterial cells were killed as beef content of the food models increased. The findings of the current study show that the chemical composition of the treated sample also plays an important role in pathogen resistance and survival, meaning that two samples with similar surface irregularities but different chemical composition might produce very different inactivation results when exposed to UVC light. PMID:27904353

  6. Supplements and athletes.

    PubMed

    Lombardo, John A

    2004-09-01

    Supplements have become a staple with athletes. Athletes take supplements to enhance their performance through replenishment of real and perceived deficiencies, anabolic action of stimulants, increased energy and alertness, and for weight control. Physicians who deal with athletes should be aware of the supplements being utilized by athletes, the athletes' desired effects and the efficacy of the supplement, the adverse effects, and whether the supplement is banned by leagues or organizations in which the athletes are competing. For those athletes who are regularly drug tested for performance enhancers, it is important to remember that one cannot be 100% sure that any supplement will not result in a positive drug test, because there is no independent agency certifying purity.

  7. Antibiotic susceptibility of Stenotrophomonas (Xanthomonas) maltophilia: comparative (NCCLS criteria) evaluation of antimicrobial drugs with the agar dilution and the agar disk diffusion (Bauer-Kirby) tests.

    PubMed

    Traub, W H; Leonhard, B; Bauer, D

    1998-01-01

    Ninety-six clinical isolates of Stenotrophomonas maltophilia were examined with the agar dilution method for susceptibility to 19 antimicrobial drugs. Doxycycline, cotrimoxazole, timentin, ofloxacin, fosfomycin, and piperacillin + tazobactam, in that order, inhibited the majority of strains. All isolates were resistant to nitrofurantoin. Concurrent disk susceptibility (Bauer-Kirby method) testing, using currently valid NCCLS interpretative criteria for Pseudomonas aeruginosa, uncovered a significant incidence of very major (category I), major (category II), and minor (categories III and IV) discrepancies for aminoglycosides, cephalosporins, chloramphenicol, and piperacillin + tazobactam and ticarcillin + clavulanic acid. Therefore, new interpretative criteria indicative of intermediate (I) susceptibility of S. maltophilia to these various antibiotics were proposed. In addition, new intermediate susceptibility criteria were proposed for the two beta-lactam-beta-lactamase inhibitor combinations. It was recommended to exclude ciprofloxacin from test batteries against this microorganism due to the wide scatter of minimal inhibitory concentration values and diameters of inhibition zones; the same was true for polymyxin B. It is hoped that the proposed modified, species-specific criteria will improve the clinical utility of laboratory-generated disk antibiograms with respect to the inherently multiple antibiotic-resistant, opportunistic pathogen S. maltophilia.

  8. Evaluation of commercial selective agars in screening for methicillin-resistant Staphylococcus aureus.

    PubMed

    Yang, Hee-Young; Suh, Jin-Tae; Lee, Hee-Joo

    2010-01-01

    To evaluate methicillin-resistant S. aureus (MRSA) detection methods, we compared (a) mannitol salt agar with cefoxitin (MSA-FX), (b) MRSASelect agar (Bio-Rad), (c) MRSA ID (bioMerieuex), and (d) CHROMagar MRSA (BD Diagnostics) as selective media for culturing nasal swab specimens collected from intensive care unit (ICU) patients and healthcare personnel. A total of 99 (17.1%) cases of MRSA were recovered from 578 specimens. Four (5.5%) cases were identified from healthcare personnel and 95 (18.8%) were from ICU patients. The sensitivity of MSA-FX, MRSASelect, MRSA ID, and CHROMagar MRSA was 83.8, 87.9, 80.8, and 84.8% after 18 hr; 92.9, 94.9, 90.9, and 91.9% after 24 hr; and 96.0, 100, 99.0, and 99.0% after 48 hr, respectively. The specificity of MSA-FX, MRSASelect, MRSA ID, and CHROMagar MRSA was 97.7, 99.0, 98.7. and 99.8% after 18 hr; 97.1, 98.5, 98.1, and 99.5% after 24 hr; and 95.2, 97.7, 97.9, and 99.0% after 48 hr, respectively. In conclusion, all four media showed good results after the 24 hr readings, but MRSA ID and CHROMagar MRSA media required readings at 48 hr due to increased sensitivity at this time point.

  9. Measuring Survival of Hematopoietic Cancer Cells with the Colony-Forming Assay in Soft Agar.

    PubMed

    Crowley, Lisa C; Waterhouse, Nigel J

    2016-08-01

    Colony-forming assays measure the ability of cells in culture to grow and divide into groups. Any cell that has the potential to form a colony may also have the potential to cause cancer or relapse in vivo. Colony-forming assays also provide an indirect measurement of cell death because any cell that is dead or dying will not continue to proliferate. The proliferative capacity of adherent cells such as fibroblasts can be determined by growing cells at low density on culture dishes and counting the number of distinct groups that form over time. Cells that grow in suspension, such as hematopoietic cells, cannot be assayed this way because the cells move freely in the media. Assays to determine the colony-forming ability of hematopoietic cells must therefore be performed in solid matrices that restrict large-scale movement of the cells. One such matrix is soft agar. This protocol describes the use of soft agar to compare the colony-forming ability of untreated hematopoietic cells to the colony-forming ability of hematopoietic cells that have been treated with a cytotoxic agent.

  10. Visualization of Biosurfactant Film Flow in a Bacillus subtilis Swarm Colony on an Agar Plate

    PubMed Central

    Kim, Kyunghoon; Kim, Jung Kyung

    2015-01-01

    Collective bacterial dynamics plays a crucial role in colony development. Although many research groups have studied the behavior of fluidic swarm colonies, the detailed mechanics of its motion remains elusive. Here, we developed a visualization method using submicron fluorescent beads for investigating the flow field in a thin layer of fluid that covers a Bacillus subtilis swarm colony growing on an agar plate. The beads were initially embedded in the agar plate and subsequently distributed spontaneously at the upper surface of the expanding colony. We conducted long-term live cell imaging of the B. subtilis colony using the fluorescent tracers, and obtained high-resolution velocity maps of microscale vortices in the swarm colony using particle image velocimetry. A distinct periodic fluctuation in the average speed and vorticity of flow in swarm colony was observed at the inner region of the colony, and correlated with the switch between bacterial swarming and growth phases. At the advancing edge of the colony, both the magnitudes of velocity and vorticity of flow in swarm colony were inversely correlated with the spreading speed of the swarm edge. The advanced imaging tool developed in this study would facilitate further understanding of the effect of micro vortices in swarm colony on the collective dynamics of bacteria. PMID:26343634

  11. An electrochemical approach to monitor pH change in agar media during plant tissue culture.

    PubMed

    Wang, Min; Ha, Yang

    2007-05-15

    In this work, metal oxide microelectrodes were developed to monitor pH change in agar media during plant tissue culture. An antimony wire was produced by a new approach "capillary melt method". The surface of the obtained antimony wire was oxidized in a potassium nitrate melt to fabricate an antimony oxide film for pH sensing. Characterization results show that the oxide layer grown on the wire surface consists of Sb(2)O(3) crystal phase. The sensing response, open-circuit potential, of the electrode has a good linear relationship (R(2)=1.00) with pH value of the test solution. Adding organic compounds into the test media would not affect the linear relationship, although the slope of the lines varied with different ingredients added. The antimony oxide electrodes were employed to continuously monitor pH change of agar culture media during a 2-week plant tissue culture of Dendrobium candidum. The antimony oxide electrode fabricated this way has the advantages of low cost, easy fabrication, fast response, and almost no contamination introduced into the system. It would be suitable for in situ and continuous pH measurement in many bio applications.

  12. Mechanical response of agar gel irradiated with Nd:YAG nanosecond laser pulses

    NASA Astrophysics Data System (ADS)

    Pérez-Gutiérrez, Francisco G.; Evans, Rodger; Camacho-López, Santiago; Aguilar, Guillermo

    2010-02-01

    Nanosecond long laser pulses are used in medical applications where precise tissue ablation with minimal thermal and mechanical collateral damage is required. When a laser pulse is incident on a material, optical energy will be absorbed by a combination of linear and nonlinear absorption according to both: laser light intensity and material properties. In the case of water or gels, the first results in heat generation and thermoelastic expansion; while the second results in an expanding plasma formation that launches a shock wave and a cavitation/boiling bubble. Plasma formation due to nonlinear absorption of nanosecond laser pulses is originated by a combination of multiphoton ionization and thermionic emission of free electrons, which is enhanced when the material has high linear absorption coefficient. In this work, we present measurements of pressure transients originated when 6 ns laser pulses are incident on agar gels with varying linear absorption coefficient, mechanical properties and irradiation geometry using laser radiant exposures above threshold for bubble formation. The underlying hypothesis is that pressure transients are composed of the superposition of both: shock wave originated by hot expanding plasma resulting from nonlinear absorption of optical energy and, thermoelastic expansion originated by heat generation due to linear absorption of optical energy. The objective of this work is to evaluate the relative contribution of each absorption mechanism to mechanical effects in agar gel. Real time pressure transients are recorded with PVDF piezoelectric sensors and time-resilved imaging from 50 μm to 10 mm away from focal point.

  13. Bromothymol blue broth: improved medium for detection of Ureaplasma urealyticum (T-strain mycoplasma).

    PubMed

    Robertson, J A

    1978-02-01

    Bromothymol blue (B) broth for the cultivation, detection, and identification of Ureaplasma urealyticum is described. In this medium, strains Cook and 960 had shorter generation times (60 min or less) and reached higher populations (over 10(8)) than have yet been reported for this species. Furthermore, the indicator changes color before the end of logarithmic growth, and the cultures retain viability for at least 1 day thereafter, greatly simplifying the handling of the organism. When the populations in cultures of these two strains and seven new isolates were determined, growth was detected earlier and proceeded to higher final titers in B broth than in urease test color medium (U-9 broth). The inclusion of antibiotics in B broth for use in clinical laboratories (B/NL broth) made the medium selective, specific, and more sensitive for the isolation of U. urealyticum. Comparison of B/NL broth with genital mycoplasma (GM) agar and U-9 broth for the primary isolation of U. urealyticum was made with 183 urethral swabs. All 70 isolates were detected on B/NL broth, but only 66 and 63 isolates were detected on GM agar and in U-9 broth, respectively. Moreover, the cultures in B/NL broth were pure and at titers that generally showed good correlation with colony counts on GM agar.

  14. Multilaboratory Comparison of Proficiencies in Susceptibility Testing of Helicobacter pylori and Correlation between Agar Dilution and E Test Methods

    PubMed Central

    Best, L. M.; Haldane, D. J. M.; Keelan, M.; Taylor, D. E.; Thomson, A. B. R.; Loo, V.; Fallone, C. A.; Lyn, P.; Smaill, F. M.; Hunt, R.; Gaudreau, C.; Kennedy, J.; Alfa, M.; Pelletier, R.; Veldhuyzen van Zanten, S. J. O.

    2003-01-01

    Susceptibility testing was performed at seven Canadian microbiology laboratories and the Helicobacter Reference Laboratory, Halifax, Nova Scotia, Canada, to assess susceptibility testing proficiency and the reproducibility of the results for clarithromycin and metronidazole and to compare the Epsilometer test (E test) method to the agar dilution reference method. Control strain Helicobacter pylori ATCC 43504 (American Type Culture Collection) and 13 clinical isolates (plus duplicates of four of these strains including ATCC 43504) were tested blindly. The National Committee for Clinical Laboratory Standards (NCCLS) guidelines for agar dilution testing were followed, and the same suspension of organisms was used for agar dilution and E test. Antimicrobials and E test strips were provided to the investigators. Methods were provided on a website (www.Helicobactercanada.org). Each center reported MICs within the stated range for strain ATCC 43504. Compared to the average MICs, interlaboratory agreements within 2 log2 dilutions were 90% (range, 69 to 100%) for clarithromycin by agar dilution, with seven very major errors [VMEs], and 85% (range, 65 to 100%) by E test, with three VMEs. Interlaboratory agreements within 2 log2 dilutions were 83% (range, 50 to 100%) for metronidazole by agar dilution, with six VMEs and eight major errors (MEs), and 75% (range, 50 to 94%) by E test, with four VMEs and four MEs. At lower and higher concentrations of antibiotic, E test MICs were slightly different from agar dilution MICs, but these differences did not result in errors. When a standardized protocol based on NCCLS guidelines was used, most participants in this study correctly identified clarithromycin- and metronidazole-susceptible and -resistant strains of H. pylori 93% of the time by either the agar dilution or E test method, and the numbers of errors were relatively equivalent by both methods. PMID:14506021

  15. Multilaboratory comparison of proficiencies in susceptibility testing of Helicobacter pylori and correlation between agar dilution and E test methods.

    PubMed

    Best, L M; Haldane, D J M; Keelan, M; Taylor, D E; Thomson, A B R; Loo, V; Fallone, C A; Lyn, P; Smaill, F M; Hunt, R; Gaudreau, C; Kennedy, J; Alfa, M; Pelletier, R; Veldhuyzen Van Zanten, S J O

    2003-10-01

    Susceptibility testing was performed at seven Canadian microbiology laboratories and the Helicobacter Reference Laboratory, Halifax, Nova Scotia, Canada, to assess susceptibility testing proficiency and the reproducibility of the results for clarithromycin and metronidazole and to compare the Epsilometer test (E test) method to the agar dilution reference method. Control strain Helicobacter pylori ATCC 43504 (American Type Culture Collection) and 13 clinical isolates (plus duplicates of four of these strains including ATCC 43504) were tested blindly. The National Committee for Clinical Laboratory Standards (NCCLS) guidelines for agar dilution testing were followed, and the same suspension of organisms was used for agar dilution and E test. Antimicrobials and E test strips were provided to the investigators. Methods were provided on a website (www.Helicobactercanada.org). Each center reported MICs within the stated range for strain ATCC 43504. Compared to the average MICs, interlaboratory agreements within 2 log(2) dilutions were 90% (range, 69 to 100%) for clarithromycin by agar dilution, with seven very major errors [VMEs], and 85% (range, 65 to 100%) by E test, with three VMEs. Interlaboratory agreements within 2 log(2) dilutions were 83% (range, 50 to 100%) for metronidazole by agar dilution, with six VMEs and eight major errors (MEs), and 75% (range, 50 to 94%) by E test, with four VMEs and four MEs. At lower and higher concentrations of antibiotic, E test MICs were slightly different from agar dilution MICs, but these differences did not result in errors. When a standardized protocol based on NCCLS guidelines was used, most participants in this study correctly identified clarithromycin- and metronidazole-susceptible and -resistant strains of H. pylori 93% of the time by either the agar dilution or E test method, and the numbers of errors were relatively equivalent by both methods.

  16. Family Living Supplement.

    ERIC Educational Resources Information Center

    Truitt, Debbie

    This family living supplement contains 125 supplemental ideas and strategies designed to help vocational home economics teachers increase student motivation and enrich the teaching process. Ideas and strategies are organized into seven sections. These are career planning, securing a job, and career success; managing financial resources, buying…

  17. Supplemental instruction in chemistry

    NASA Astrophysics Data System (ADS)

    Lundeberg, Mary A.

    This study was designed to measure some effects of supplemental instruction in chemistry. Supplemental instruction is a peer-led cooperative learning program that encourages students to develop conceptual understanding by articulating both understandings and misconceptions in a think-aloud fashion. Supplemental instruction was offered three hours weekly outside of class and lab time for students in four classes of General Organic and Biological Chemistry. Over a two-year period 108 students volunteered to participate in this program; 45 students did not participate. As measured by final grades in chemistry and responses to a questionnaire, supplemental instruction was effective in increasing students' achievement in chemistry. Further research is needed to determine the in-depth effects of supplemental instruction on students' learning, problem solving, and self-esteem.

  18. Beware of Fraudulent 'Dietary Supplements'

    MedlinePlus

    ... Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products For Consumers Home For Consumers ... Supplements Dietary Supplements More in Consumer Updates Animal & Veterinary Children's Health Cosmetics Dietary Supplements Drugs Food Medical ...

  19. Herbs, Supplements and Alternative Medicines

    MedlinePlus

    ... Living With Diabetes > Treatment and Care > Medication > Other Treatments > Herbs, Supplements, and Alternative Medicines Share: Print Page Text ... magazine: meds-other, In this section Medication Other Treatments Herbs, Supplements, and Alternative Medicines Types of Dietary Supplements ...

  20. Effect of bicarbonate concentration on aerobic growth of campylobacter in a fumarate-pyruvate medium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of the present study was to examine the effect of sodium bicarbonate (NaHCO3) concentration on aerobic growth of Campylobacter in a fumarate-pyruvate medium. Fumarate-pyruvate broth medium was supplemented with 0.00 to 0.10% NaHCO3 and inoculated with Campylobacter coli 33559, Campyloba...

  1. Preparation and characterization of agar-based nanocomposite films reinforced with bimetallic (Ag-Cu) alloy nanoparticles.

    PubMed

    Arfat, Yasir Ali; Ahmed, Jasim; Jacob, Harsha

    2017-01-02

    Agar-based active nanocomposite films were prepared by incorporating silver-copper (Ag-Cu) alloy nanoparticles (NPs) (0.5-4wt%) into glycerol plasticized agar solution. Thermo-mechanical, morphological, structural, and optical properties of the nanocomposite films were characterized by texture analyzer, differential scanning calorimetry (DSC), scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transforms infrared (FTIR) spectroscopy, and surface color measurement. Tensile strength and the melting temperature of the film increased linearly with NPs loading concentration. Color, transparency and UV barrier properties of agar films were influenced by the reinforcement of Ag-Cu NPs. XRD analysis confirmed the crystalline structure of the Agar/Ag-Cu nanocomposite films, whereas the smoothness and the homogeneity of film surface strongly reduced as observed through the SEM. The nanocomposite films exhibited a profound antibacterial activity against both Gram-positive (Listeria monocytogenes) and Gram-negative (Salmonella enterica sv typhimurium) bacteria. Overall, the agar nanocomposite films could be used as packaging material for food preservation by controlling foodborne pathogens and spoilage bacteria.

  2. Infrared thermography analysis of thermal diffusion induced by RF magnetic field on agar phantoms loaded with magnetic nanoparticles

    NASA Astrophysics Data System (ADS)

    Bante-Guerra, Jose; Macías, J. D.; Caballero-Aguilar, L.; Vales-Pinzón, C.; Alvarado-Gil, J. J.

    2013-02-01

    Recently, several treatments for fighting malignant tumors have been designed. However these procedures have well known inconveniences, depending on their applicability, tumor size and side effects, among others. Magnetic hyperthermia is a safe, non-invasive method for cancer therapy. This treatment is applied via elevation of target tissue temperature by dissipation of heat from Magnetic Nanoparticles (MNPs), previously located within the tumor. The induction of heat causes cell death and therefore the removal of the tumor. In this work the thermal diffusion in phantoms of agar loaded with magnetic nanoparticles (MNPs) is studied using the infrared thermography technique, which is widely used in biology/medicine (e.g. skin temperature mapping). Agar is one of the materials used to simulate different types of body tissues, these samples are known as "phantoms". Agar is of natural origin, low cost and high degree of biocompatibility. In this work the agar gel was embedded with MNPs by coprecipitation and placed in an alternating magnetic field radiation. As a consequence, the energy from the radiation source is dissipated as heat and then transferred from the MNP to the gel, increasing its temperature. For the temperature analysis, the samples of agar gel were stimulated by RF magnetic field generated by coils. Heating was measured with infrared thermography using a Thermovision A20M infrared camera. Thermographic images allowed obtaining the dependence of thermal diffusion in the phantom as a function of the magnitude of the applied RF magnetic field and the load of magnetic particles.

  3. Agar extraction from integrated multitrophic aquacultured Gracilaria vermiculophylla: evaluation of a microwave-assisted process using response surface methodology.

    PubMed

    Sousa, A M M; Alves, V D; Morais, S; Delerue-Matos, C; Gonçalves, M P

    2010-05-01

    Microwave-assisted extraction (MAE) of agar from Gracilaria vermiculophylla, produced in an integrated multitrophic aquaculture (IMTA) system, from Ria de Aveiro (northwestern Portugal), was tested and optimized using response surface methodology. The influence of the MAE operational parameters (extraction time, temperature, solvent volume and stirring speed) on the physical and chemical properties of agar (yield, gel strength, gelling and melting temperatures, as well as, sulphate and 3,6-anhydro-L-galactose contents) was evaluated in a 2(4) orthogonal composite design. The quality of the extracted agar compared favorably with the attained using traditional extraction (2 h at 85 degrees Celsius) while reducing drastically extraction time, solvent consumption and waste disposal requirements. Agar MAE optimum results were: an yield of 14.4 + or - 0.4%, a gel strength of 1331 + or - 51 g/cm(2), 40.7 + or - 0.2 degrees Celsius gelling temperature, 93.1 + or - 0.5 degrees Celsius melting temperature, 1.73 + or - 0.13% sulfate content and 39.4 + or - 0.3% 3,6-anhydro-L-galactose content. Furthermore, this study suggests the feasibility of the exploitation of G. vermiculophylla grew in IMTA systems for agar production.

  4. Evaluation of Albicans ID2 and Biggy agar for the isolation and direct identification of vaginal yeast isolates.

    PubMed

    Ilkit, Macit; Hilmioglu, Suleyha; Tasbakan, Meltem; Aydemir, Sohret

    2007-06-01

    In this study, 250 vaginal samples from patients with vulvovaginal candidosis were inoculated onto two chromogenic media, Albicans ID(2) and Biggy agar, as well as onto Sabouraud chloramphenicol agar, yielding a total of 63 yeast (25.2 %) on all three media. These strains were identified as Candida glabrata in 20 (31.8 %) samples, Candida albicans in 15 samples (23.8 %), Candida tropicalis in 10 samples (15.9 %), Candida krusei in five samples (7.9 %), Candida kefyr in five samples (7.9 %), Candida dubliniensis in four samples (6.3 %), Candida parapsilosis in two samples (3.2 %) and Candida guilliermondii in two samples (3.2 %). Mixed fungal cultures and bacterial growth or filamentous fungi were not detected on any of the selected media. The sensitivity and specificity of the Albicans ID(2) and Biggy agar with regard to the identification of C. albicans were 80.0 and 64.6 %, and 86.7 and 56.3 %, respectively. This study showed these two chromogenic media to be as effective as Sabouraud chloramphenicol agar with respect to fungal detection. However, neither Albicans ID(2) nor Biggy agar was sufficient for reliable differentiation of yeasts to the species level.

  5. Comparison of Mast Burkholderia Cepacia, Ashdown + Gentamicin, and Burkholderia Pseudomallei Selective Agar for the Selective Growth of Burkholderia Spp.

    PubMed

    Edler, Carola; Derschum, Henri; Köhler, Mirko; Neubauer, Heinrich; Frickmann, Hagen; Hagen, Ralf Matthias

    2017-03-01

    Reliable identification of pathogenic Burkholderia spp. like Burkholderia mallei and Burkholderia pseudomallei in clinical samples is desirable. Three different selective media were assessed for reliability and selectivity with various Burkholderia spp. and nontarget organisms. Mast Burkholderia cepacia agar, Ashdown + gentamicin agar, and B. pseudomallei selective agar were compared. A panel of 116 reference strains and well-characterized clinical isolates, comprising 30 B. pseudomallei, 20 B. mallei, 18 other Burkholderia spp., and 48 nontarget organisms, was used for this assessment. While all B. pseudomallei strains grew on all three tested selective agars, the other Burkholderia spp. showed a diverse growth pattern. Nontarget organisms, i.e., nonfermentative rod-shaped bacteria, other species, and yeasts, grew on all selective agars. Colony morphology did not allow unambiguous discrimination. While the assessed selective media reliably allowed the growth of a wide range of B. pseudomallei strains, growth of other Burkholderia spp. is only partially ensured. Growth of various nontarget organisms has to be considered. Therefore, the assessed media can only be used in combination with other confirmative tests in the diagnostic procedure for the screening for melioidosis or glanders.

  6. Comparison of Mast Burkholderia Cepacia, Ashdown + Gentamicin, and Burkholderia Pseudomallei Selective Agar for the Selective Growth of Burkholderia Spp.

    PubMed Central

    Edler, Carola; Derschum, Henri; Köhler, Mirko; Neubauer, Heinrich; Frickmann, Hagen; Hagen, Ralf Matthias

    2017-01-01

    Reliable identification of pathogenic Burkholderia spp. like Burkholderia mallei and Burkholderia pseudomallei in clinical samples is desirable. Three different selective media were assessed for reliability and selectivity with various Burkholderia spp. and nontarget organisms. Mast Burkholderia cepacia agar, Ashdown + gentamicin agar, and B. pseudomallei selective agar were compared. A panel of 116 reference strains and well-characterized clinical isolates, comprising 30 B. pseudomallei, 20 B. mallei, 18 other Burkholderia spp., and 48 nontarget organisms, was used for this assessment. While all B. pseudomallei strains grew on all three tested selective agars, the other Burkholderia spp. showed a diverse growth pattern. Nontarget organisms, i.e., nonfermentative rod-shaped bacteria, other species, and yeasts, grew on all selective agars. Colony morphology did not allow unambiguous discrimination. While the assessed selective media reliably allowed the growth of a wide range of B. pseudomallei strains, growth of other Burkholderia spp. is only partially ensured. Growth of various nontarget organisms has to be considered. Therefore, the assessed media can only be used in combination with other confirmative tests in the diagnostic procedure for the screening for melioidosis or glanders. PMID:28386468

  7. Identification of non-Listeria spp. bacterial isolates yielding a β-D-glucosidase-positive phenotype on Agar Listeria according to Ottaviani and Agosti (ALOA).

    PubMed

    Angelidis, Apostolos S; Kalamaki, Mary S; Georgiadou, Sofia S

    2015-01-16

    Agar Listeria according to Ottaviani and Agosti (ALOA) is the mandatory medium used for the detection and enumeration of Listeria monocytogenes in foods according to the official International Organization for Standardization (ISO) methods. On ALOA, Listeria spp. appear as bluish-green colonies due to the production of β-D-glucosidase, an enzyme that cleaves 5-bromo-4-chloro-3-indolyl-β-D-glucopyranoside, a chromogenic substrate included in the formulation of the medium. The present work reports on bacterial isolates (n=64) from ready-to-eat soft cheeses, which are able to grow on ALOA, forming bluish-green colonies and therefore phenotypically resemble Listeria spp. All isolates were also capable of growing on the selective media PALCAM and RAPID L'mono. The isolates were characterised with biochemical tests including those specified in the ISO standards for the confirmation of Listeria spp. and identified via partial sequencing of their 16S rRNA gene. According to sequencing results the isolates represented 12 different bacterial species or species-groups belonging to seven different genera: Bacillus spp. (B. circulans, B. clausii, B. licheniformis and B. oleronius), Cellulosimicrobium spp. (C. funkei), Enterococcus spp. (E. faecalis, E. faecium/durans), Kocuria spp. (K. kristinae), Marinilactibacillus spp. (M. psychrotolerans), Rothia spp. (R. terrae) and Staphylococcus spp. (S. sciuri and S. saprophyticus subsp. saprophyticus/xylosus). Cellulosimicrobium spp. have never been previously isolated from foods. These results significantly extend the list of bacteria previously known as capable of growing on ALOA as bluish-green colonies and suggest that there may be room for further improvement in the medium's inhibitory properties towards non-Listeria spp., Gram-positive bacteria present in foods.

  8. Visualization of Thermal Distribution Caused by Focused Ultrasound Field in an Agar Phantom

    NASA Astrophysics Data System (ADS)

    Kim, Jungsoon; Kim, Moojoon; Ha, Kanglyeol

    2011-07-01

    Ultrasound waves have been widely used not only in medical diagnostic systems but also in medical treatment. There has been increasing interest in the thermal distribution caused by ultrasound waves. In this study, using thermochromic particles, a visualization method was suggested in a mimic phantom for organic materials. By blending various thermochromic particles with different critical temperatures, the thermal field distribution in the phantom could be observed. The effect of a concave-type ultrasound transducer on the temperature distribution in an agar phantom mixed with thermochromic particles was observed. The temperature distribution corresponded to changes in the brightness distribution of gray. It was confirmed that the thermal distribution pattern in the vicinity of the focal area varies with the time exposure to ultrasound waves.

  9. Copper removal by algae Gelidium, agar extraction algal waste and granulated algal waste: kinetics and equilibrium.

    PubMed

    Vilar, Vítor J P; Botelho, Cidália M S; Boaventura, Rui A R

    2008-03-01

    Biosorption of copper ions by an industrial algal waste, from agar extraction industry has been studied in a batch system. This biosorbent was compared with the algae Gelidium itself, which is the raw material for agar extraction, and the industrial waste immobilized with polyacrylonitrile (composite material). The effects of contact time, pH, ionic strength (IS) and temperature on the biosorption process have been studied. Equilibrium data follow both Langmuir and Langmuir-Freundlich models. The parameters of Langmuir equilibrium model were: q(max)=33.0mgg(-1), K(L)=0.015mgl(-1); q(max)=16.7mgg(-1), K(L)=0.028mgl(-1) and q(max)=10.3mgg(-1), K(L)=0.160mgl(-1) respectively for Gelidium, algal waste and composite material at pH=5.3, T=20 degrees C and IS=0.001M. Increasing the pH, the number of deprotonated active sites increases and so the uptake capacity of copper ions. In the case of high ionic strengths, the contribution of the electrostatic component to the overall binding decreases, and so the uptake capacity. The temperature has little influence on the uptake capacity principally for low equilibrium copper concentrations. Changes in standard enthalpy, Gibbs energy and entropy during biosorption were determined. Kinetic data at different solution pH (3, 4 and 5.3) were fitted to pseudo-first-order and pseudo-second-order models. The adsorptive behaviour of biosorbent particles was modelled using a batch reactor mass transfer kinetic model, which successfully predicts Cu(II) concentration profiles.

  10. Evaluation of agar dilution and broth microdilution methods to determine the disinfectant susceptibility.

    PubMed

    Wu, Guoyan; Yang, Qianru; Long, Mei; Guo, Lijuan; Li, Bei; Meng, Yue; Zhang, Anyun; Wang, Hongning; Liu, Shuliang; Zou, Likou

    2015-11-01

    A variety of disinfectants have been widely used in veterinary hygiene, food industries and environments, which could induce the development of bacterial resistance to disinfectants. The methods used to investigate antimicrobial effects of disinfectant vary considerably among studies, making comparisons difficult. In this study, agar dilution and broth microdilution methods were used to compare the antimicrobial activities of four quaternary ammonium compounds (QACs) against foodborne and zoonotic pathogens. The potential relationship between the presence of QACs resistance genes and phenotypic resistance to QACs was also investigated. Our results indicated that the minimum inhibitory concentrations (MICs) determined by two methods might be different depended upon different QACs and bacteria applied. Regardless of the testing methods, Klebsiella pneumoniae was more tolerant among Gram-negative strains to four QACs, followed by Salmonella and Escherichia coli. The agreement between MICs obtained by the two methods was good, for benzalkonium chloride (78.15%), didecyldimethylammonium chloride (DDAC) (82.35%), cetylpyridinium chloride (CTPC) (97.48%) and cetyltrimethylammonium bromide (CTAB) (99.16%), respectively. Among all Gram-negative bacteria, 94.55% (n=52) of qacEΔ1-positive strains showed higher MICs (512 mg l(-1)) to CTAB. The qacEΔ1 gene was highly associated (P<0.05) with the high MICs of QACs (⩾512 mg l(-1)). In addition, DDAC remained as the most effective disinfectant against both Gram-positive and Gram-negative bacteria. This is the first study that compared the agar dilution and broth microdilution methods to assess the antimicrobial activity of QACs. The study demonstrated the need to standardize method that would be used in evaluating QACs antimicrobial properties in the future.

  11. Mycobacterium and Aerobic Actinomycete Culture: Are Two Medium Types and Extended Incubation Times Necessary?

    PubMed

    Simner, Patricia J; Doerr, Kelly A; Steinmetz, Lory K; Wengenack, Nancy L

    2016-04-01

    Mycobacterial cultures are historically performed using a liquid medium and a solid agar medium with an incubation period of up to 60 days. We performed a retrospective analysis of 21,494 mycobacterial and aerobic actinomycetes cultures performed over 10 months to determine whether two medium types remain necessary and to investigate whether culture incubation length can be shortened. Specimens were cultured using Bactec MGIT liquid medium and Middlebrook 7H11/S7H11 solid medium with incubation periods of 42 and 60 days, respectively. Time-to-positivity and the identity of isolates recovered from each medium were evaluated. A total of 1,205/21,494 cultures (6%) were positive on at least one medium. Of the 1,353 isolates recovered, 1,110 (82%) were nontuberculous mycobacteria, 145 (11%) were aerobic actinomycetes, and 98 (7%) wereMycobacterium tuberculosiscomplex. Assessing medium types, 1,121 isolates were recovered from solid medium cultures, 922 isolates were recovered from liquid medium cultures, and 690 isolates were recovered on both media. Liquid cultures were positive an average of 10 days before solid cultures when the two medium types were positive (P< 0.0001). Isolates detected on solid medium after 6 weeks of incubation included 65 (5%) nontuberculous mycobacteria, 4 (0.3%) aerobic actinomycetes, and 2 (0.2%) isolates from theM. tuberculosiscomplex. Medical chart review suggested that most of these later-growing isolates were insignificant, as the diagnosis was already known, or they were considered colonizers/contaminants. This study reaffirms the need for both liquid medium and solid medium for mycobacterial and aerobic actinomycetes culture and demonstrates that solid medium incubation times may be reduced to 6 weeks without significantly impacting sensitivity.

  12. Supplements for exotic pets.

    PubMed

    Mejia-Fava, Johanna; Colitz, Carmen M H

    2014-09-01

    The use of supplements has become commonplace in an effort to complement traditional therapy and as part of long-term preventive health plans. This article discusses historical and present uses of antioxidants, vitamins, and herbs. By complementing traditional medicine with holistic and alternative nutrition and supplements, the overall health and wellness of exotic pets can be enhanced and balanced. Further research is needed for understanding the strengths and uses of supplements in exotic species. Going back to the animals' origin and roots bring clinicians closer to nature and its healing powers.

  13. Hypermedia as medium

    NASA Technical Reports Server (NTRS)

    Dede, Christopher J.

    1990-01-01

    Claims and rebuttals that hypermedia (the associative, nonlinear interconnection of multimedia materials) is a fundamentally innovative means of thinking and communicating are described. This representational architecture has many advantages that make it a major advance over other media; however, it also has several intrinsic problems that severly limits its effectiveness as a medium. These advantages and limits in applications are discussed.

  14. Holographic recording medium

    NASA Technical Reports Server (NTRS)

    Gange, Robert Allen (Inventor)

    1977-01-01

    A holographic recording medium comprising a conductive substrate, a photoconductive layer and an electrically alterable layer of a linear, low molecular weight hydrocarbon polymer has improved fatigue resistance. An acrylic barrier layer can be interposed between the photoconductive and electrically alterable layers.

  15. Isolation and in vitro culture of trypanosomes from Leptodactylus ocellatus from the Atlantic Forest in a new experimental culture medium.

    PubMed

    Lemos, M; Souza, C S F; da Costa, S C Gonçalves; Souto-Padrón, T; D'Agosto, M

    2013-02-01

    The purpose of this study was to verify the in vitro development of Trypanosoma sp. isolated from Leptodactylus ocellatus frogs under a new protocol using a biphasic medium composed of Novy, McNeal, and Nicolle (NNN) blood agar medium as a solid phase and liver infusion, brain heart infusion, and tryptose (LIBHIT) medium as a liquid phase. Blood forms, collected by cardiac puncture or after the maceration of different organs, were inoculated in culture tubes containing the biphasic medium composed by NNN and LIBHIT. Trypanosomes were observed 4 days postinoculation; most bloodstream trypomastigotes had differentiated into epimastigotes and amastigotes by this time. Trypomastigotes were again observed in older cultures (7 days). Parasites were successfully subcultured for 8 mo in this medium and successfully cryopreserved. The present study provides a new protocol medium for the isolation and culture of anuran trypanosomes.

  16. Criteria for the interpretation of the pipemidic acid agar diffusion test by the Kirby-Bauer method.

    PubMed

    Grimm, H

    1983-01-01

    The antibiotic sensitivity of 296 strains of Pseudomonas aeruginosa and 294 isolates of other species was measured by the agar diffusion test with 20 micrograms pipemidic acid (Deblaston) discs on Mueller-Hinton agar by the Kirby-Bauer method. The correlation between inhibition zone diameter and minimal inhibitory concentration was worked out by regression analysis. In all bacterial species investigated, an inhibition zone of 14 mm or more indicates sensitivity to pipemidic acid. For Pseudomonas aeruginosa an intermediate zone of 11 to 13 mm is recommended.

  17. Cashew apple juice as microbial cultivation medium for non-immunogenic hyaluronic acid production

    PubMed Central

    Oliveira, Adriano H.; Ogrodowski, Cristiane C.; de Macedo, André C.; Santana, Maria Helena A.; Gonçalves, Luciana R.B.

    2013-01-01

    In this work, natural cashew apple juice was used as cultivation medium as an alternative to substitute brain heart infusion medium. The effect of aeration and juice supplementation with yeast extract on the production of hyaluronic acid in batch fermentation was also investigated. Similar levels of cell mass were obtained in inoculum using cashew apple juice supplemented with yeast extract or the conventional brain heart infusion medium. Fermentation in Erlenmeyer flasks produced low biomass and hyaluronic acid concentrations. The hyaluronic acid concentration and viscosity increased from 0.15 g/L and 3.87 cP (no aeration or medium supplementation) to 1.76 g/L and 107 cP, when aeration (2 vvm) and 60 g/L of yeast extract were used. The results suggest the production of low-molecular weight hyaluronic acid oligomers instead of the high molecular weight polymer. PMID:24688498

  18. [The comparative evaluation of differential diagnostic characteristics of Endo growth medium of different manufacturers].

    PubMed

    Shepelin, A P; Martchikhina, I I; Polosenko, O V; Skladan, G Ye

    2013-05-01

    The article deals with the results of comparative study of differential diagnostic characteristics of Endo growth medium of different foreign manufacturers permitted to be applied in the Russian Federation and the national Endo agar. The enhanced kit of museum test-strains and clinical material from patients were used. It is established that morphology, size and number of clumps of most enterobacteria growing in Tndo medium manufactured by Merck, Pronadisa, HiMedia and the state research center of applied microbiology and biotechnology have minor morphological differences and match the characteristics declared by manufacturers. The indicator of degree of detection (degree of inoculation) of pathogenic enterobacteria from clinical material onto Endo medium manufactured by the state research center of applied microbiology and biotechnology matched the indicators of media from foreign manufacturers. It is demonstrated that Endo growth medium manufactured by the state research center of applied microbiology and biotechnology not only is equal to import analogues but in particular cases even excels them.

  19. FDA 101: Dietary Supplements

    MedlinePlus

    ... Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products For Consumers Home For Consumers ... Knowledge About Vitamins More in Consumer Updates Animal & Veterinary Children's Health Cosmetics Dietary Supplements Drugs Food Medical ...

  20. Breastfeeding: Vitamin D Supplementation

    MedlinePlus

    ... able to synthesize additional vitamin D through routine sunlight exposure. However, published reports of cases of vitamin ... a vitamin supplement or from adequate exposure to sunlight. A number of factors decrease the amount of ...

  1. Supplements to Textbook Materials.

    ERIC Educational Resources Information Center

    Holmes, Ken

    1994-01-01

    Describes the many kinds of materials that English teachers can draw upon to enrich and expand students' experiences with literature. Outlines ancillary materials used to supplement the study of William Shakespeare's "Julius Caesar." (HB)

  2. Parenteral iron supplementation.

    PubMed

    Kumpf, V J

    1996-08-01

    Indications for the use of parenteral iron are limited to conditions in which the oral supplementation of iron is not possible or fails. An overview of iron balance and iron requirements is presented to describe situations in which iron supplementation may be required. When parenteral iron supplementation is required, careful attention to proper dosing and administration is necessary to optimize efficacy and safety. The purpose of this article is to review the literature regarding the clinical use of parenteral iron therapy and provide guidelines on dosing and administration. Methods of iron dextran administration, including the IV and intramuscular injection of undiluted drug and total dose infusion, are compared. Complications associated with the use of parenteral iron are also be reviewed. Finally, the use of iron supplementation in patients receiving parenteral nutrition care explored.

  3. Dietary Supplements for Toddlers

    MedlinePlus

    ... about which supplements are needed and the amounts. Iron Deficiency Iron deficiency does occur among some young children and ... need to receive at least 15 milligrams of iron a day in their food, but many fail ...

  4. Iron supplements (image)

    MedlinePlus

    The mineral iron is an essential nutrient for humans because it is part of blood cells, which carry oxygen to all body cells. There is no conclusive evidence that iron supplements contribute to heart attacks.

  5. Osteogenic differentiation of immature osteoblasts: Interplay of cell culture media and supplements.

    PubMed

    Brauer, A; Pohlemann, T; Metzger, W

    2016-01-01

    Differentiation of immature osteoblasts to mature osteoblasts in vitro initially was induced by supplementing the medium with β-gylcerophosphate and dexamethasone. Later, ascorbic acid, vitamin D3, vitamin K3 and TGFβ1 were used in varying concentrations as supplements to generate a mature osteoblast phenotype. We tested the effects of several combinations of cell culture media, seeding protocols and osteogenic supplements on osteogenic differentiation of human primary osteoblasts. Osteogenic differentiation was analyzed by staining alkaline phosphatase (ALP) with 5-bromo-4-chloro-3-indolyl-phosphate/nitro blue tetrazolium (BCIP/NBT) and by von Kossa staining of deposited calcium phosphate. The combinations of culture media and supplements significantly influenced osteogenic differentiation, but the seeding protocol did not. Staining of ALP and calcium phosphate could be achieved only if our own mix of osteogenic supplements was used in combination with Dulbecco's modified Eagle medium or if a commercial mix of osteogenic supplements was used in combination with osteoblast growth medium. Especially for von Kossa, we observed great variations in the staining intensity. Because osteogenic differentiation is a complex process, the origin of the osteoblasts, cell culture media and osteogenic supplements should be established by preliminary experiments to achieve optimal differentiation. Staining of ALP or deposited calcium phosphate should be supplemented with qRT-PCR studies to learn more about the influence of specific supplements on osteogenic markers.

  6. Liquid chromatographic extraction medium

    DOEpatents

    Horwitz, E.P.; Dietz, M.L.

    1994-09-13

    A method and apparatus are disclosed for extracting strontium and technetium values from biological, industrial and environmental sample solutions using a chromatographic column. An extractant medium for the column is prepared by generating a solution of a diluent containing a Crown ether and dispersing the solution on a resin substrate material. The sample solution is highly acidic and is introduced directed to the chromatographic column and strontium or technetium is eluted using deionized water. 1 fig.

  7. Liquid chromatographic extraction medium

    DOEpatents

    Horwitz, E. Philip; Dietz, Mark L.

    1994-01-01

    A method and apparatus for extracting strontium and technetium values from biological, industrial and environmental sample solutions using a chromatographic column is described. An extractant medium for the column is prepared by generating a solution of a diluent containing a Crown ether and dispersing the solution on a resin substrate material. The sample solution is highly acidic and is introduced directed to the chromatographic column and strontium or technetium is eluted using deionized water.

  8. Caffeine supplementation during IVM improves frequencies of nuclear maturation and preimplantation development of dromedary camel oocytes following IVF.

    PubMed

    Fathi, Mohamed; Seida, Adel A; Sobhy, Refaat R; Darwish, Gamal M; Badr, Magdy R; Moawad, Adel R

    2014-06-01

    Caffeine supplementation during oocyte IVM has been reported to improve preimplantation embryo development and the quality of in vitro-produced blastocysts in a range of species; but no studies have been done in camels. The present study investigated the effect of caffeine supplementation during dromedary camel oocyte IVM on nuclear maturation rates, IVF events, and subsequent preimplantation development. Cumulus-oocyte complexes obtained at slaughter were matured in vitro in caffeine supplemented medium either for 30 hours (caffeine 30 hours) or in the medium without caffeine supplement for 24 hours and then transferred to freshly prepared IVM medium supplemented with 10 mM caffeine for another 6 hours (caffeine 6 hours). Cumulus-oocyte complexes matured for 30 hours in the medium without caffeine supplement were used as a control. Matured oocytes were fertilized in vitro by epididymal spermatozoa of mature male camels collected from a local slaughterhouse. Eighteen hours after insemination, presumptive zygotes were cultured in modified KSOMaa medium for 7 days. Maturation and fertilization rates were significantly higher in the caffeine 6-hour group compared with the control group (P < 0.05), whereas IVM of oocytes in caffeine-supplemented medium for 30 hours did not affect these parameters (P > 0.05). Interestingly, IVM of oocytes in caffeine supplemented medium for 6 hours significantly (P < 0.05) increased the frequencies of blastocyst development by more than two-fold when compared with control (27.78% vs. 11.76%). In conclusion, culturing dromedary camel oocytes in maturation medium without caffeine for 24 hours and then in the medium supplemented with 10 mM caffeine for 6 hours during 30-hour IVM can significantly improve frequencies of nuclear maturation, fertilization rate, and subsequent preimplantation development.

  9. Improved selective medium for the isolation of Treponema hyodysenteriae.

    PubMed Central

    Kunkle, R A; Kinyon, J M

    1988-01-01

    An agar medium with improved selection for Treponema hyodysenteriae was developed. Cultures of T. hyodysenteriae and T. innocens, feces from 11 clinically normal pigs, and colonic contents from 6 pigs with gross lesions consistent with swine dysentery were diluted in phosphate-buffered saline and plated on Trypticase soy agar (BBL Microbiology Systems, Cockeysville, Md.) with 5% citrated bovine blood (TSA), TSA with 400 micrograms of spectinomycin per ml (TSA-S400), TSA-S400 with 25 micrograms each of colistin and vancomycin per ml, and TSA with 5% pig feces extract and five antimicrobial agents (spiramycin, rifampin, vancomycin, colistin, and spectinomycin) (BJ). Viable numbers of T. hydodysenteriae grown on BJ were virtually identical to those for TSA, TSA-S400, and TSA-S400 with colistin and vancomycin. Pure cultures of four isolates of T. hyodysenteriae and three isolates of T. innocens were sustained through six subcultures on BJ. Fecal floras were completely inhibited on BJ for 14 of 17 fecal samples from both groups of pigs. A total of 461 colonic specimens from naturally occurring cases of porcine intestinal disease were plated on TSA-S400 and BJ. T. hyodysenteriae was isolated on both TSA-S400 and BJ for 69 specimens and on BJ alone for an additional 19 specimens. PMID:3235663

  10. Quantitative observations of cavitation activity in a viscoelastic medium.

    PubMed

    Collin, Jamie R T; Coussios, Constantin C

    2011-11-01

    Quantitative experimental observations of single-bubble cavitation in viscoelastic media that would enable validation of existing models are presently lacking. In the present work, single bubble cavitation is induced in an agar gel using a 1.15 MHz high intensity focused ultrasound transducer, and observed using a focused single-element passive cavitation detection (PCD) transducer. To enable quantitative observations, a full receive calibration is carried out of a spherically focused PCD system by a bistatic scattering substitution technique that uses an embedded spherical scatterer and a hydrophone. Adjusting the simulated pressure received by the PCD by the transfer function on receive and the frequency-dependent attenuation of agar gel enables direct comparison of the measured acoustic emissions with those predicted by numerical modeling of single-bubble cavitation using a modified Keller-Miksis approach that accounts for viscoelasticity of the surrounding medium. At an incident peak rarefactional pressure near the cavitation threshold, period multiplying is observed in both experiment and numerical model. By comparing the two sets of results, an estimate of the equilibrium bubble radius in the experimental observations can be made, with potential for extension to material parameter estimation. Use of these estimates yields good agreement between model and experiment.

  11. Evaluation of the Biomic V3 Microbiology System for Identification of Selected Species on BBL CHROMagar Orientation Agar and CHROMagar MRSA Medium

    PubMed Central

    Baron, Ellen Jo; D'Souza, Holly; Qi Wang, Andrew; Gibbs, David L.

    2008-01-01

    The Biomic V3 microbiology system identifies bacteria by reading the color of colonies selected by the user. For CHROMagar orientation, Biomic results agreed with conventional methods for 94% of the strains assayed. For CHROMagar MRSA, Biomic correctly identified 100% of the strains tested and did not misidentify two methicillin-susceptible Staphylococcus aureus strains growing on the plates. PMID:18701661

  12. Effects of immersion disinfection of agar-alginate combined impressions on the surface properties of stone casts.

    PubMed

    Iwasaki, Yukiko; Hiraguchi, Hisako; Iwasaki, Eriko; Yoneyama, Takayuki

    2016-01-01

    This study investigated the effects of disinfection of agar-alginate combined impressions on the surface properties of the resulting stone casts. Two brands of cartridge-form agar impression material and one alginate impression material were used. Agar-alginate combined impressions of smooth glass plates were prepared. The impressions were immersed in 0.55% ortho-phthalaldehyde solution or 0.5% sodium hypochlorite solution for 1, 3, 5 and 10 min. A stone cast made with an impression that had not been immersed was prepared as a control. The surface roughness (Ra) of the stone casts was measured, and the cast surfaces were observed by SEM. Immersion of agar-alginate combined impressions in 0.5% sodium hypochlorite solution for up to 10 min had no serious adverse effects on the surface properties of the stone casts. In contrast, even 1 min of immersion in 0.55% ortho-phthalaldehyde solution caused deterioration of the cast surface properties.

  13. Choline chloride based ionic liquid analogues as tool for the fabrication of agar films with improved mechanical properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the present paper, we test the suitability of Choline-Cl/urea (DES-U) and Choline-Cl/glycerol (DES-G) eutectic mixtures at 1:2 molar ratios for the production of agar biodegradable films. A three-step process is proposed: pre-solubilization of polymer in DES followed by compression-molding and s...

  14. Campylobacter in broiler slaughter samples assessed by direct count on mCCDA and Campy-Cefex agar.

    PubMed

    Gonsalves, Camila Cristina; Borsoi, Anderlise; Perdoncini, Gustavo; Rodrigues, Laura Beatriz; do Nascimento, Vladimir Pinheiro

    2016-01-01

    Campylobacter spp. cause foodborne illnesses in humans primarily through the consumption of contaminated chicken. The aim of this study was to evaluate the United States Department of Agriculture's (USDA) recommended methodology, protocol MLG 41.02, for the isolation, identification and direct plate counting of Campylobacter jejuni and C. coli samples from the broiler slaughtering process. A plating method using both mCCDA and Campy-Cefex agars is recommended to recover Campylobacter cells. It is also possible to use this method in different matrices (cloacal swabs and water samples). Cloacal swabs, samples from pre-chiller and post-chiller carcasses and samples of pre-chiller, chiller and direct supply water were collected each week for four weeks from the same flock at a slaughterhouse located in an abattoir in southern Brazil. Samples were analyzed to directly count Campylobacter spp., and the results showed a high frequency of Campylobacter spp. on Campy-Cefex agar. For the isolated species, 72% were identified as Campylobacter jejuni and 38% as Campylobacter coli. It was possible to count Campylobacter jejuni and Campylobacter coli from different samples, including the water supply samples, using the two-agar method. These results suggest that slaughterhouses can use direct counting methods with both agars and different matrices as a monitoring tool to assess the presence of Campylobacter bacteria in their products.

  15. Intelligent pH indicator film composed of agar/potato starch and anthocyanin extracts from purple sweet potato.

    PubMed

    Choi, Inyoung; Lee, Jun Young; Lacroix, Monique; Han, Jaejoon

    2017-03-01

    A new colorimetric pH indicator film was developed using agar, potato starch, and natural dyes extracted from purple sweet potato, Ipomoea batatas. Both agar and potato starch are solid matrices used to immobilize natural dyes, anthocyanins. The ultraviolet-visible (UV-vis) spectrum of anthocyanin extract solutions and agar/potato starch films with anthocyanins showed color variations to different pH values (pH 2.0-10.0). Fourier transform infrared (FT-IR) and UV-vis region spectra showed compatibility between agar, starch, and anthocyanin extracts. Color variations of pH indicator films were measured by a colorimeter after immersion in different pH buffers. An application test was conducted for potential use as a meat spoilage sensor. The pH indicator films showed pH changes and spoilage point of pork samples, changing from red to green. Therefore, the developed pH indicator films could be used as a diagnostic tool for the detection of food spoilage.

  16. [An observation on the histological structure of Oncomelania hupensis soft tissue by agar-paraffin double-embedding method].

    PubMed

    Tan, Ping; Zhang, Jie; Li, Qing; Yu, Zhi-jun

    2014-12-01

    In order to study the histological structure of Oncomelania hupensis soft tissue, the fixed soft tissues of O. hupensis were pre-embedded in the agar and made blocks, then dehydrated, transparentized, immersed in paraffin, sectioned, and stained with haematoxylin-eosin (HE). Permanent slides of O. hupensis soft tissue were obtained. The histological structure of soft tissues was clear under the microscope.

  17. Recovery and differentiation of long ripened cheese microflora through a new cheese-based cultural medium.

    PubMed

    Neviani, Erasmo; De Dea Lindner, Juliano; Bernini, Valentina; Gatti, Monica

    2009-05-01

    A partial picture of the typical microflora of PDO Parmigiano Reggiano cheese was achieved by studying the cultivability of lactic acid bacteria associated with its manufacturing and ripening. A comprehensive sampling design allowed for the analysis of the cheese microflora during its production over 20 months of ripening. An innovative cheese agar medium (CAM) was prepared after testing 18 formulations all based on grated Parmigiano Reggiano ripened cheese. During cheese manufacturing and ripening, different samples were sampled and their microflora was recovered using CAM in comparison with other traditional media. Colonies which formed units from the different agar media tested were picked and isolated; the phylogenetic positions of 154 isolated strains were studied at level of species by 16S-rRNA gene sequencing. CAM seems to be able to recover the minority population coming from milk and whey starter, hardly estimable, during the first hours of production, on traditional media.

  18. Thermal inactivation and sublethal injury kinetics of Salmonella enterica and Listeria monocytogenes in broth versus agar surface.

    PubMed

    Wang, Xiang; Devlieghere, Frank; Geeraerd, Annemie; Uyttendaele, Mieke

    2017-02-21

    The objective of the present study was to compare the thermal inactivation and sublethal injury kinetics of Salmonella enterica and Listeria monocytogenes in broth (suspended cells) and on solid surface (agar-seeded cells). A 3-strain cocktail of S. enterica or L. monocytogenes inoculated in broth or on agar was subjected to heating in a water bath at various set temperatures (55.0, 57.5 and 60.0°C for S. enterica and 60.0, 62.5 and 65°C for L. monocytogenes). The occurrence of sublethally injured cells was determined by comparing enumerations on nonselective (TSAYE) and selective (XLD or ALOA) media. Results showed that the inactivation curves obtained from selective media were log-linear, and significant shoulders (p<0.05) were observed on some of the inactivation curves from TSAYE media. The D-values derived from the total population were higher than those from the uninjured cells. Generally, cells on agar surface exhibited higher heat resistance than those in broth. For S. enterica, cell injury increased with the exposure time, no difference was observed when treated at temperatures from 55.0 to 60.0°C, while for L. monocytogenes, cell injury increased significantly with heating time and treatment temperature (from 60.0 to 65°C). Moreover, the degree of sublethal injury affected by thermal treatment in broth or on agar surface depended upon the target microorganism. Higher proportions of injured S. enterica cells were observed for treatment in broth than on agar surface, while the opposite was found for L. monocytogenes. The provided information may be used to assess the efficacy of thermal treatment processes on surfaces for inactivation of S. enterica and L. monocytogenes, and it provides insight into the sublethally injured survival state of S. enterica and L. monocytogenes treated in liquid or on solid food.

  19. Control of Drug Diffusion Behavior of Xanthan and Locust Bean Gum Gel by Agar Gel.

    PubMed

    Hishikawa, Yoshihiro; Kakino, Yukari; Tsukamoto, Hoshi; Tahara, Kohei; Onodera, Risako; Takeuchi, Hirofumi

    2016-01-01

    Oral gel formulations are known as easy to administer drug products for patients who have problems taking drugs including those with conditions such as dysphagia. In addition, there are numerous commercially available oral gel products, most of which are immediate-release formulation that release their pharmaceutical ingredient content by diffusion. This study is focused on developing oral gel formulations that reduce the dosing frequency and dosage compared to the conventional types. This is with the aim of facilitating the use of gel formulations for producing pharmaceutical agents with different dose regimens, thereby enhancing patient convenience. Here, we used naturally derived high-molecular-weight agar (Ag), xanthan gum (Xa), and locust bean gum (Lo) as gel bases to prepare a variety of gel membranes, and evaluated the diffusion coefficient of the model substances. The result revealed that the Ag content in the Xa-Lo combination gel concentration-dependently increased the diffusion coefficient. Moreover, these findings were applied in an attempt to mask the taste of intensely bitter levofloxacin. The results indicated that the Xa-Lo combination gel exhibited a significantly superior masking effect to that of the Ag gel. This study demonstrates the feasibility of using oral gel formulations to modulate the controlled-release functionality of pharmaceutical agents.

  20. Characterisation of Elastic and Acoustic Properties of an Agar-Based Tissue Mimicking Material.

    PubMed

    Brewin, M P; Birch, M J; Mehta, D J; Reeves, J W; Shaw, S; Kruse, C; Whiteman, J R; Hu, S; Kenz, Z R; Banks, H T; Greenwald, S E

    2015-10-01

    As a first step towards an acoustic localisation device for coronary stenosis to provide a non-invasive means of diagnosing arterial disease, measurements are reported for an agar-based tissue mimicking material (TMM) of the shear wave propagation velocity, attenuation and viscoelastic constants, together with one dimensional quasi-static elastic moduli and Poisson's ratio. Phase velocity and attenuation coefficients, determined by generating and detecting shear waves piezo-electrically in the range 300 Hz-2 kHz, were 3.2-7.5 ms(-1) and 320 dBm(-1). Quasi-static Young's modulus, shear modulus and Poisson's ratio, obtained by compressive or shear loading of cylindrical specimens were 150-160 kPa; 54-56 kPa and 0.37-0.44. The dynamic Young's and shear moduli, derived from fitting viscoelastic internal variables by an iterative statistical inverse solver to freely oscillating specimens were 230 and 33 kPa and the corresponding relaxation times, 0.046 and 0.036 s. The results were self-consistent, repeatable and provide baseline data required for the computational modelling of wave propagation in a phantom.

  1. Theoretical and experimental NMR studies on muscimol from fly agaric mushroom (Amanita muscaria)

    NASA Astrophysics Data System (ADS)

    Kupka, Teobald; Wieczorek, Piotr P.

    2016-01-01

    In this article we report results of combined theoretical and experimental NMR studies on muscimol, the bioactive alkaloid from fly agaric mushroom (Amanita muscaria). The assignment of 1H and 13C NMR spectra of muscimol in DMSO-d6 was supported by additional two-dimensional heteronuclear correlated spectra (2D NMR) and gauge independent atomic orbital (GIAO) NMR calculations using density functional theory (DFT). The effect of solvent in theoretical calculations was included via polarized continuum model (PCM) and the hybrid three-parameter B3LYP density functional in combination with 6-311++G(3df,2pd) basis set enabled calculation of reliable structures of non-ionized (neutral) molecule and its NH and zwitterionic forms in the gas phase, chloroform, DMSO and water. GIAO NMR calculations, using equilibrium and rovibrationally averaged geometry, at B3LYP/6-31G* and B3LYP/aug-cc-pVTZ-J levels of theory provided muscimol nuclear magnetic shieldings. The theoretical proton and carbon chemical shifts were critically compared with experimental NMR spectra measured in DMSO. Our results provide useful information on its structure in solution. We believe that such data could improve the understanding of basic features of muscimol at atomistic level and provide another tool in studies related to GABA analogs.

  2. Theoretical and experimental NMR studies on muscimol from fly agaric mushroom (Amanita muscaria).

    PubMed

    Kupka, Teobald; Wieczorek, Piotr P

    2016-01-15

    In this article we report results of combined theoretical and experimental NMR studies on muscimol, the bioactive alkaloid from fly agaric mushroom (Amanita muscaria). The assignment of (1)H and (13)C NMR spectra of muscimol in DMSO-d6 was supported by additional two-dimensional heteronuclear correlated spectra (2D NMR) and gauge independent atomic orbital (GIAO) NMR calculations using density functional theory (DFT). The effect of solvent in theoretical calculations was included via polarized continuum model (PCM) and the hybrid three-parameter B3LYP density functional in combination with 6-311++G(3df,2pd) basis set enabled calculation of reliable structures of non-ionized (neutral) molecule and its NH and zwitterionic forms in the gas phase, chloroform, DMSO and water. GIAO NMR calculations, using equilibrium and rovibrationally averaged geometry, at B3LYP/6-31G* and B3LYP/aug-cc-pVTZ-J levels of theory provided muscimol nuclear magnetic shieldings. The theoretical proton and carbon chemical shifts were critically compared with experimental NMR spectra measured in DMSO. Our results provide useful information on its structure in solution. We believe that such data could improve the understanding of basic features of muscimol at atomistic level and provide another tool in studies related to GABA analogs.

  3. Mercury and its bioconcentration factors in fly agaric (Amanita muscaria) from spatially distant sites in Poland.

    PubMed

    Falandysz, J; Lipka, K; Mazur, A

    2007-09-01

    Total mercury content has been determined in the fruiting bodies of fly agaric (Amanita muscaria) and topsoil layer (0-10 cm) collected from 14 spatially distant sites across Poland. Mercury was measured by cold-vapor atomic absorption spectroscopy (CV-AAS) after nitric acid (mushrooms) or nitric acid and sulfuric acid (soil) digestion of the samples. The caps, depending on the site, contained total mercury at mean concentrations from 0.24+/-0.13 to 1.4+/-0.6 microg/g dm (median 0.19-1.4 microg/g dm), and stalks from 0.18+/-0.06 to 0.71+/-0.26 microg/g dm (median 0.18-0.67 microg/g dm). An overall-mean the total mercury content for 204 caps and stalks was, respectively, 0.73+/-0.55 (0.05-3.3 microg/g dm) and 0.43+/-0.33 (0.09-2.3 microg/g dm).

  4. Usefulness of Candida ID2 agar for the presumptive identification of Candida dubliniensis.

    PubMed

    Eraso, Elena; Sahand, Ismail H; Villar-Vidal, María; Marcos, Cristina; Dolores Moragues, María; Madariaga, Lucila; Pontón, José; Quindós, Guillermo

    2006-11-01

    CHROMagar Candida and Candida ID2 are widely used for the isolation and presumptive identification of Candida spp. based on the color of the colonies on these two media. We have studied the usefulness of these chromogenic media for differentiating Candida dubliniensis from Candida albicans isolates. One hundred isolates of C. dubliniensis and 100 C. albicans isolates were tested on Candida ID2, CHROMagar Candida (CHROMagar), and CHROMagar Candida reformulated by BBL. CHROMagar Candida and CHROMagar Candida BBL did not allow a clear differentiation of the two species based upon the shade of the green color of C. dubliniensis colonies. However, on Candida ID2, all C. dubliniensis isolates produced turquoise blue colonies whereas 91% of C. albicans colonies were cobalt blue. The sensitivity and the specificity for differentiating between C. dubliniensis fromC. albicans on Candida ID2 were 100% and 91%, respectively; whereas on CHROMagar Candida these values were 63% and 89% and on CHROMagar Candida BBL they were 18% and 98%. Candida ID2 agar provides a simple and accurate laboratory approach for the identification and differentiation of C. dubliniensis on the basis of the colony color.

  5. Antimicrobial susceptibility of Brazilian Clostridium difficile strains determined by agar dilution and disk diffusion.

    PubMed

    Fraga, Edmir Geraldo; Nicodemo, Antonio Carlos; Sampaio, Jorge Luiz Mello

    2016-01-01

    Clostridium difficile is a leading cause of diarrhea in hospitalized patients worldwide. While metronidazole and vancomycin are the most prescribed antibiotics for the treatment of this infection, teicoplanin, tigecycline and nitazoxanide are alternatives drugs. Knowledge on the antibiotic susceptibility profiles is a basic step to differentiate recurrence from treatment failure due to antimicrobial resistance. Because C. difficile antimicrobial susceptibility is largely unknown in Brazil, we aimed to determine the profile of C. difficile strains cultivated from stool samples of inpatients with diarrhea and a positive toxin A/B test using both agar dilution and disk diffusion methods. All 50 strains tested were sensitive to metronidazole according to CLSI and EUCAST breakpoints with an MIC90 value of 2μg/mL. Nitazoxanide and tigecycline were highly active in vitro against these strains with an MIC90 value of 0.125μg/mL for both antimicrobials. The MIC90 were 4μg/mL and 2μg/mL for vancomycin and teicoplanin, respectively. A resistance rate of 8% was observed for moxifloxacin. Disk diffusion can be used as an alternative to screen for moxifloxacin resistance, nitazoxanide, tigecycline and metronidazole susceptibility, but it cannot be used for testing glycopeptides. Our results suggest that C. difficile strains from São Paulo city, Brazil, are susceptible to metronidazole and have low MIC90 values for most of the current therapeutic options available in Brazil.

  6. Development and validation of a microbiological agar assay for determination of cefuroxime sodium in pharmaceutical preparations.

    PubMed

    Schmidt, Cleber A; Agarrayua, Danielle A; Laporta, Luciane V; Machado, Jaison C; Manfio, Maria L; Bittencourt, Celso F

    2009-06-01

    Cefuroxime (CFU) is a semi-synthetic cephalosporin with a relatively broad-spectrum antimicrobial activity, and belongs to the second generation of cephalosporins. Regarding the quality control of medicines, a validated microbiological assay for determination of cefuroxime sodium in pharmaceutical formulations has not been reported yet. With this purpose, this paper reports the development and validation of a simple, sensitive, accurate and reproducible agar diffusion method to quantify CFU sodium in injectable formulations. The assay is based on the inhibitory effect of CFU upon the strain of Staphylococcus aureus ATCC 6538P used as test microorganism. The results were treated statistically by analysis of variance and were found to be linear (r=0.9998) in the selected range of 8.0-32.0 microg/ml; precise [repeatability: relative standard deviation (RSD)=1.56%; intermediate precision: between-day RSD=1.27%; between analyst RSD=1.13%] and accurate (101.58%). The bioassay specificity was studied by evaluation of degraded sample at 50 degrees C with analysis at 0, 24 and 48 h in parallel with the pharmacopeial liquid chromatography method for CFU. The results demonstrated the validity of the proposed bioassay, which allows reliable quantitation of CFU sodium in pharmaceutical samples and therefore can be used as a useful alternative methodology for the routine quality control of this medicine.

  7. Dichromated agar: a promising doped biocopolymer for real time holographic recording

    NASA Astrophysics Data System (ADS)

    Bolte, Michèle; Israëli, Yaël; Rivaton, Agnès; Lessard, Roger A.

    2006-09-01

    Agar is a natural polysaccharide which, when doped with dichromate ammonium, can be considered as a promising light sensitive material used for real time hologram recording. The volume transmission gratings were recorded with a Kypton laser at 413 nm and they were read in real-time with a He/Ne laser at 632.8 nm contrary to dichromated gelatin. The so obtained holograms formed were phase holograms due to a refraction index modulation. The optimisation of chemical and physical parameters was investigated in order to form high quality holograms. It was demonstrated the crucial role played by the remaining water in the final film on the value of the diffraction efficiency. In the optimal conditions, a maximum diffraction efficiency of 37 % was attained. Both on-off experiments and the storage of the exposed materials at room temperature and in the dark reveal that the holograms were stable. An attempt to rationalize the set of results in terms of chemical structure of the polymeric matrix and of its ability to stabilize chromium (V) is presented.

  8. Physico-chemical and microstructural properties of fish gelatin/agar bio-based blend films.

    PubMed

    Mohajer, Setareh; Rezaei, Masoud; Hosseini, Seyed Fakhreddin

    2017-02-10

    This study was conducted with the aim of improving the physico-chemical properties of fish gelatin (FG) based films. For this purpose, FG was blended with agar (AG) in different compositions to acquire biodegradable films (100:0, 80:20, 60:40, 50:50 & 0:100, FG:AG). The obtained results showed that the AG addition strongly increased the film rigidity and resistance to fracture, while reducing the film stretchability, mainly at 50FG: 50AG ratio. AG incorporation greatly reduced the water vapor permeability (WVP) and solubility of gelatin films, as this decline for the blend film with a 50:50 ratio of biopolymers has been about 41% and 66%, respectively (p<0.05). Additional advantages of AG inclusion to FG films are the reduction of the UV-transmittance. Both polymers showed good compatibility, as demonstrated by scanning electron microscopy (SEM) and atomic force microscopy (AFM) images. Therefore, the blend composition influenced the properties of FG/AG bio-based films.

  9. Development and Validation of a Microbiological Agar Assay for Determination of Orbifloxacin in Pharmaceutical Preparation

    PubMed Central

    Cazedey, Edith C. L.; Salgado, Hérida R. N.

    2011-01-01

    Orbifloxacin is a fluoroquinolone with broad-spectrum antimicrobial activity, and belongs to the third generation of quinolones. Regarding the quality control of medicines, a validated microbiological assay for determination of orbifloxacin in pharmaceutical formulations has not as yet been reported. For this purpose, this paper reports the development and validation of a simple, sensitive, accurate and reproducible agar diffusion method to quantify orbifloxacin in tablet formulations. The assay is based on the inhibitory effect of orbifloxacin upon the strain of Staphylococcus aureus ATCC 25923 used as test microorganism. The results were treated statistically by analysis of variance and were found to be linear (r = 0.9992) in the selected range of 16.0–64.0 μg/mL, precise with relative standard deviation (RSD) of repeatability intraday = 2.88%, intermediate precision RSD = 3.33%, and accurate (100.31%). The results demonstrated the validity of the proposed bioassay, which allows reliable orbifloxacin quantitation in pharmaceutical samples and therefore can be used as a useful alternative methodology for the routine quality control of this medicine. PMID:24310597

  10. Comparison of sorbitol MacConkey and hemorrhagic coli agars for recovery of Escherichia coli O157:H7 from brie, ice cream, and whole milk.

    PubMed

    Hammack, T S; Feng, P; Amaguaña, R M; June, G A; Sherrod, P S; Andrews, W H

    1997-01-01

    The relative efficacies of hemorrhagic coli (HC) agar and several formulations of sorbitol MacConkey (SorMac) agar, with and without 0.1% (w/v) 4-methyllumbelliferyl-beta-D-glucuronide (MUG), in recovering unstressed and heat-stressed Escherichia coli O157:H7 from Brie cheese, ice cream, and whole milk were determined. Recovery of unstressed E. coli O157:H7 was determined quantitatively by spread-plating diluted samples onto different agars and performing plate counts. Recovery of stressed E. coli O157:H7 was determined qualitatively by enriching samples in modified trypticase soy broth, streaking the incubated enrichments, and isolating E. coli O157:H7 colonies from the agars. HC agar and the SorMac agar formulations did not differ significantly in their ability to recover unstressed E. coli O157:H7 from ice cream and whole milk; however, HC agar recovered significantly more unstressed E. coli O157:H7 from Brie cheese than did the SorMac agar formulations. Bacteriological Analytical Manual and Oxoid SorMac agar formulations made from individual ingredients, did not differ significantly in recovering unstressed E. coli O157:H7 from Brie cheese. The efficiency of the commercially available Oxoid SorMac agar could not be determined because of overgrowth by indigenous microflora. HC and SorMac agars did not differ significantly in recovering stressed E. coli O157:H7 from Brie cheese, ice cream, and whole milk. MUG had no apparent effect on recovery of either stressed or unstressed E. coli O157:H7 from the dairy foods examined.

  11. Relative diffusion of paramagnetic metal complexes of MRI contrast agents in an isotropic hydrogel medium.

    PubMed

    Weerakoon, Bimali Sanjeevani; Osuga, Toshiaki

    2017-03-01

    The observation of molecular diffusion by means of magnetic resonance imaging (MRI) is significant in the evaluation of the metabolic activity of living tissues. Series of MRI examinations were conducted on a diffusion model to study the behaviour of the diffusion process of different-molecular-weight (MW) paramagnetic MRI contrast agents in an isotropic agar hydrogel medium. The model consisted of a solidified 1 % agar gel with an initial concentration of 0.5 mmol/L contrast solution layered on top of the gel. The diffusion process was monitored at pre-determined time intervals of immediately, 1, 6, 9, 23, and 48 h after introduction of the contrast agents onto the agar gel with a T1-weighted spin-echo (SE) pulse sequence. Three types of paramagnetic contrast agents, Gd-DTPA with a MW of 547.57 g/mol, Prohance with a MW of 558.69 g/mol and MnCl2 with a MW of 125.84 g/mol, resulted in an approximate average diffusional displacement ratio of 1:1:2 per hour, respectively, within 48 h of the experiment. Therefore, the results of this study supported the hypothesis that the rate of the diffusion process of MRI contrast agents in the agar hydrogel medium is inversely related to their MWs. However, more repetitions are necessary under various types of experimental conditions and also with various types of contrast media of different MWs for further confirmation and validation of these results.

  12. DENSE MEDIUM CYCLONE OPTIMIZATON

    SciTech Connect

    Gerald H. Luttrell; Chris J. Barbee; Peter J. Bethell; Chris J. Wood

    2005-06-30

    Dense medium cyclones (DMCs) are known to be efficient, high-tonnage devices suitable for upgrading particles in the 50 to 0.5 mm size range. This versatile separator, which uses centrifugal forces to enhance the separation of fine particles that cannot be upgraded in static dense medium separators, can be found in most modern coal plants and in a variety of mineral plants treating iron ore, dolomite, diamonds, potash and lead-zinc ores. Due to the high tonnage, a small increase in DMC efficiency can have a large impact on plant profitability. Unfortunately, the knowledge base required to properly design and operate DMCs has been seriously eroded during the past several decades. In an attempt to correct this problem, a set of engineering tools have been developed to allow producers to improve the efficiency of their DMC circuits. These tools include (1) low-cost density tracers that can be used by plant operators to rapidly assess DMC performance, (2) mathematical process models that can be used to predict the influence of changes in operating and design variables on DMC performance, and (3) an expert advisor system that provides plant operators with a user-friendly interface for evaluating, optimizing and trouble-shooting DMC circuits. The field data required to develop these tools was collected by conducting detailed sampling and evaluation programs at several industrial plant sites. These data were used to demonstrate the technical, economic and environmental benefits that can be realized through the application of these engineering tools.

  13. Use of agar diffusion assay to evaluate bactericidal activity of formulations of alkaline salts of fatty acids against bacteria associated with poultry processing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The agar diffusion assay was used to examine antibacterial activity of alkaline salts of fatty acids (FA). Wells in agar media seeded with bacteria were filled with FA-potassium hydroxide (KOH) solutions, plates were incubated, and zones of inhibition were measured. The relationship between bacteric...

  14. The survival of human skin stored by refrigeration at 4 degrees C in McCoy's 5A medium: does oxygenation of the medium improve storage time?

    PubMed

    DeBono, R; Rao, G S; Berry, R B

    1998-07-01

    To establish the viable storage time of human skin stored by refrigeration at 4 degrees C in McCoy's 5A medium and to establish whether oxygenating the medium improves the viable storage time, the following experiment was conducted. Eighty discs of human split-thickness skin graft, each 3 mm in diameter, were stored in 40 sterile sealable containers under four different conditions: in 0.9% saline, in McCoy's 5A medium, in oxygenated McCoy's 5A medium, and in carbon dioxide supplemented McCoy's 5A medium. Skin graft viability was assessed using tissue culture. Skin stored in saline was viable for only 1 week, whereas skin stored in McCoy's 5A medium and in oxygenated McCoy's 5A medium was viable for 4 weeks. Skin stored in carbon dioxide supplemented McCoy's 5A solution did not even survive the first week. These findings show that McCoy's 5A medium allows at least 4 weeks of viable human skin storage by refrigeration at 4 degrees C. Furthermore, oxygenating the medium does not seem to improve the viable storage time, and carbon dioxide supplementation is detrimental. The advantages of skin storage by refrigeration and the implications of the above findings are discussed. A clinical case in which split-thickness skin was stored for approximately 5 weeks and still resulted in good graft take is quoted as an example of our experience with the use of McCoy's 5A medium.

  15. Development of an Improved Selective and Differential Medium for Isolation of Salmonella spp.

    PubMed Central

    Park, Sang-Hyun; Ryu, Sangryeol

    2012-01-01

    We describe an improved selective, differential, and cost-effective medium, XA medium, which contains d-arabinose, to facilitate the selective isolation of Salmonella spp. The sensitivity and the specificity of XA medium were compared to those of xylose lysine desoxycholate agar (XLD) using stock cultures and naturally contaminated food samples. XA medium and XLD were evaluated with a total of 82 Salmonella and 69 non-Salmonella stock cultures. Of 82 strains of Salmonella spp. tested, 76 produced a characteristic black colony on XA medium and XLD. The remaining 6 strains belonged to Salmonella enterica serovars Berta (n = 1), Paratyphi A (n = 1), Gallinarum (n = 2), and Pullorum (n = 2). The sensitivities of XA medium and XLD were identical (92.7%). Citrobacter freundii (n = 21) and Proteus mirabilis (n = 21) stock cultures produced black colonies on XLD, whereas only 4 strains of P. mirabilis appeared as black colonies on XA medium. In the second phase of the study, a total of 180 food samples were cultured onto XA medium and XLD after selective enrichment. The sensitivities of XA medium and XLD were equal (100%), and a total of 6 Salmonella strains were isolated from the 180 food samples. The specificity of XA medium (92.0%) was superior to that of XLD (73.0%), with a total of 14 and 47 false-positive results found on XA medium and XLD, respectively. On the basis of its good specificity, XA medium is useful for the isolation of Salmonella spp. from food samples. PMID:22814469

  16. Chromium and zinc uptake by algae Gelidium and agar extraction algal waste: kinetics and equilibrium.

    PubMed

    Vilar, Vítor J P; Botelho, Cidália M S; Boaventura, Rui A R

    2007-11-19

    Biosorption of chromium and zinc ions by an industrial algal waste, from agar extraction industry has been studied in a batch system. This biosorbent was compared with the algae Gelidium itself, which is the raw material for agar extraction, and the industrial waste immobilized with polyacrylonitrile (composite material). Langmuir and Langmuir-Freundlich equilibrium models describe well the equilibrium data. The parameters of Langmuir equilibrium model at pH 5.3 and 20 degrees C were for the algae, q(L)=18 mg Cr(III)g(-1) and 13 mgZn(II)g(-1), K(L) = 0.021l mg(-1)Cr(III) and 0.026l mg(-1) Zn(II); for the algal waste, q(L)=12 mgCr(III)g(-1) and 7mgZn(II)g(-1), K(L)=0.033lmg(-1) Cr(III) and 0.042l mg(-1) Zn(II); for the composite material, q(L) = 9 mgCr(III)g(-1) and 6 mgZn(II)g(-1), K(L)=0.032l mg(-1)Cr(III) and 0.034l mg(-1)Zn(II). The biosorbents exhibited a higher preference for Cr(III) ions and algae Gelidium is the best one. The pseudo-first-order Lagergren and pseudo-second-order models fitted well the kinetic data for the two metal ions. Kinetic constants and equilibrium uptake concentrations given by the pseudo-second-order model for an initial Cr(III) and Zn(II) concentration of approximately 100 mgl(-1), at pH 5.3 and 20 degrees C were k(2,ads)=0.04 g mg(-1)Cr(III)min(-1) and 0.07 g mg(-1)Zn(II)min(-1), q(eq)=11.9 mgCr(III)g(-1) and 9.5 mgZn(II)g(-1) for algae; k(2,ads)=0.17 g mg(-1)Cr(III)min(-1) and 0.19 g mg(-1)Zn(II)min(-1), q(eq)=8.3 mgCr(III)g(-1) and 5.6 mgZn(II)g(-1) for algal waste; k(2,ads)=0.01 g mg(-1)Cr(III)min(-1) and 0.18 g mg(-1)Zn(II)min(-1), q(eq)=8.0 mgCr(III)g(-1) and 4.4 mgZn(II)g(-1) for composite material. Biosorption was modelled using a batch adsorber mass transfer kinetic model, which successfully predicts Cr(III) and Zn(II) concentration profiles. The calculated average homogeneous diffusivities, D(h), were 4.2 x 10(-8), 8.3 x 10(-8) and 1.4 x 10(-8)cm(2)s(-1) for Cr(III) and 4.8 x 10(-8), 9.7 x 10(-8) and 6.2 x 10(-8)cm(2)s(-1

  17. Brown-red pigment formation by the mycelial phase of a clinical isolate of Histoplasma capsulatum on Staib agar. A preliminary report.

    PubMed

    Staib, F; Grosse, G

    1996-04-01

    In an HIV-positive patient, the suspected diagnosis of histoplasmosis capsulatum (being the first opportunistic infection indicating AIDS) on the basis of histopathological findings in biopsy material could be proved by culture on Staib agar (syn. Guizotia abyssinica creatinine agar, bird seed agar, etc.). On Staib agar, after 4 weeks at 26 degrees C, there was a cockade-like colony growth, consisting of a white centre, followed by a brown-red pigmented zone surrounded by a border of submerged mycelial growth of tan to brownish colour. Morphologically, there was a moderate formation of tuberculate macroconidia and a heavy formation of microconidia. On neutral Sabouraud's dextrose agar, there was a colony formation without pigment (albino type) free of tuberculate macroconidia and microconidia. Proposals for further investigation of these preliminary observations are made.

  18. Evaluation of the antibacterial effects of vancomycin hydrochloride released from agar-gelatin-bioactive glass composites.

    PubMed

    Rivadeneira, Josefina; Di Virgilio, Ana Laura; Audisio, M Carina; Boccaccini, Aldo R; Gorustovich, Alejandro A

    2015-01-13

    The aim of this work was to evaluate the perfomance of agar-gelatin (AG) composites and AG-containing 45S5 bioactive glass (BG) microparticles (AGBG) in relation to their water uptake capacity, sustained release of a drug over time, and antibacterial effects. The composites were fabricated by the gel-casting method. To impart the local drug release capacity, vancomycin hydrochloride (VC) was loaded in the composites in concentrations of 0.5 and 1 mg ml(-1). VC release was assessed in distilled water at 37 °C up to 72 h and quantified spectrophotometrically. The antibacterial activity of composites was evaluated by the inhibition zone test and the plate count method. The experiments were performed in vitro up to 48 h on three staphylococcus strains: Staphylococcus aureus ATCC29213, S. aureus ATCC6538 and Staphylococcus epidermidis ATCC12228. The results showed that the addition of BG to AG composites did not affect the degree of water uptake. The release of VC was significantly affected by the presence of BG. VC release was higher from AGBGVC films than from AGVC ones over prolonged incubation times. Bacterial inhibition zones were found around the composites. The halos were larger when the cells were put in contact with AGVC composites than when they were put in contact with AGBGVC ones. Nevertheless, the viable count method demonstrated that the composites inhibited Staphylococcus cell growth with no statistical differences. In conclusion, the addition of BG did not reflect an improvement in the parameters studied. On the other hand, composites loaded with VC would have a role in prophylaxis against bacterial infection.

  19. Preparation and application of agar/alginate/collagen ternary blend functional food packaging films.

    PubMed

    Wang, Long-Feng; Rhim, Jong-Whan

    2015-09-01

    Ternary blend agar/alginate/collagen (A/A/C) hydrogel films with silver nanoparticles (AgNPs) and grapefruit seed extract (GSE) were prepared. Their performance properties, transparency, tensile strength (TS), water vapor permeability (WVP), water contact angle (CA), water swelling ratio (SR), water solubility (WS), and antimicrobial activity were determined. The A/A/C film was highly transparent, and both AgNPs and GSE incorporated blend films (A/A/C(AgNPs) and A/A/C(GSE)) exhibited UV-screening effect, especially, the A/A/C(GSE) film had high UV-screening effect without sacrificing the transmittance. In addition, the A/A/C blend films formed efficient hydrogel film with the water holding capacity of 23.6 times of their weight. Both A/A/C(AgNPs) and A/A/C(GSE) composite films exhibited strong antimicrobial activity against both Gram-positive (Listeria monocytogenes) and Gram-negative (Escherichia coli) food-borne pathogenic bacteria. The test results of fresh potatoes packaging revealed that all the A/A/C ternary blend films prevented forming of condensed water on the packaged film surface, both A/A/C(AgNPs) and A/A/C(GSE) composite films prevented greening of potatoes during storage. The results indicate that the ternary blend hydrogel films incorporated with AgNPs or GSE can be used not only as antifogging packaging films for highly respiring fresh agriculture produce, but also as an active food packaging system utilizing their strong antimicrobial activity.

  20. In vitro antifungal susceptibility testing of Scopulariopsis brevicaulis strains using agar diffusion method.

    PubMed

    Skóra, Magdalena; Macura, Anna B

    2011-01-01

    The genus Scopulariopsis is a common soil saprotroph and has been isolated from air, organic waste and also from plant, animal and human tissues. Scopulariopsis has mainly been associated in humans with superficial mycoses, but it has also been described as the cause of subcutaneous and invasive infections. The most common aetiological agent of infections in humans is Scopulariopsis brevicaulis. This species has been reported to be resistant in vitro to broad-spectrum antifungal agents available today. The aim of the study was to establish in vitro antifungal susceptibility of 35 S. brevicaulis strains against amphotericin B (AMB), flucytosine (FC), caspofungin (CAS), terbinafine (TER), ciclopirox (CIC), voriconazole (VOR), clotrimazole (CTR), miconazole (MCZ), econazole (ECO), ketoconazole (KET), itraconazole (ITR), and fluconazole (FLU). Antifungal susceptibility tests were evaluated by an agar diffusion method (Neo-Sensitabs, Rosco, Denmark). AMB, FC, CAS, ITR and FLU showed no antifungal activity against S. brevicaulis. TER, CIC, CTR, KET, VOR, ECO, and MCZ revealed inhibitory activity for S. brevicaulis, but it varied for each of the drugs. The best antifungal effect was observed for TER and CIC. All isolates had large inhibition zones for TER and CIC. CTR was also inhibitory for all tested S. brevicaulis isolates, but the diameters of inhibition zones were smaller than for TER and CIC. Nearly 89% isolates showed inhibition zones for KET and the mean diameter of the inhibition zone was comparable to CTR. The least antifungal activity exhibited VQR, ECO and MCZ. Because of the multiresistance of S. brevicaulis, infections due to this species may not respond to particular antifungal treatment and other therapeutic approaches should be considered, e.g., combined therapy and/or surgery.

  1. Psychology: Teacher Supplement.

    ERIC Educational Resources Information Center

    Stark, Rebecca

    This supplement provides teachers with tests, quizzes, answers to questions in the text, and general teaching information for using the student text, "Psychology," by Rebecca Stark. Quizzes included are on the topics of human development; the nervous system; the brain; cognitive development; sensation and perception; conditioning; learning;…

  2. Use of CHROMagar Candida medium for isolation of yeasts from dental samples.

    PubMed Central

    Beighton, D; Ludford, R; Clark, D T; Brailsford, S R; Pankhurst, C L; Tinsley, G F; Fiske, J; Lewis, D; Daly, B; Khalifa, N

    1995-01-01

    A new differential medium, CHROMagar Candida, for the isolation of clinically important yeasts was investigated to determine its usefulness in facilitating the study of oral yeasts. The recovery of yeasts on the medium was not significantly different from the recovery on Sabouraud dextrose agar. The identities of 450 green colonies on CHROMagar Candida, presumptively identified as Candida albicans on the basis of the manufacturer's instructions, were confirmed by testing for beta-N-acetylgalactosaminidase. Candida tropicalis also formed distinctive colonies, and other yeasts including Candida (Torulopsis) glabrata, Candida Parapsilosis, Candida Magnoliae, Candida lusitaniae, Candida Famata, Candida kefir, and Saccharomyces cerevisiae were readily distinguished from C. albicans and C. tropicalis isolates. CHROMagar Candida is a very useful medium, and its use will facilitate the study of yeasts associated with dental diseases. PMID:8576366

  3. Weight Loss Nutritional Supplements

    NASA Astrophysics Data System (ADS)

    Eckerson, Joan M.

    Obesity has reached what may be considered epidemic proportions in the United States, not only for adults but for children. Because of the medical implications and health care costs associated with obesity, as well as the negative social and psychological impacts, many individuals turn to nonprescription nutritional weight loss supplements hoping for a quick fix, and the weight loss industry has responded by offering a variety of products that generates billions of dollars each year in sales. Most nutritional weight loss supplements are purported to work by increasing energy expenditure, modulating carbohydrate or fat metabolism, increasing satiety, inducing diuresis, or blocking fat absorption. To review the literally hundreds of nutritional weight loss supplements available on the market today is well beyond the scope of this chapter. Therefore, several of the most commonly used supplements were selected for critical review, and practical recommendations are provided based on the findings of well controlled, randomized clinical trials that examined their efficacy. In most cases, the nutritional supplements reviewed either elicited no meaningful effect or resulted in changes in body weight and composition that are similar to what occurs through a restricted diet and exercise program. Although there is some evidence to suggest that herbal forms of ephedrine, such as ma huang, combined with caffeine or caffeine and aspirin (i.e., ECA stack) is effective for inducing moderate weight loss in overweight adults, because of the recent ban on ephedra manufacturers must now use ephedra-free ingredients, such as bitter orange, which do not appear to be as effective. The dietary fiber, glucomannan, also appears to hold some promise as a possible treatment for weight loss, but other related forms of dietary fiber, including guar gum and psyllium, are ineffective.

  4. Examples of Dietary Supplement Interactions

    MedlinePlus

    ... is absorbed by the body.Supplement: Saw PalmettoPossible drug-supplement interaction with:Birth control pills. Can decrease effects of estrogen in the body, which can reduce the effectiveness of birth control ...

  5. Dietary Supplements: What Is Safe?

    MedlinePlus

    ... and side effects of dietary supplements Dietary supplement advertising and promotion Talking with your doctor about dietary ... Statistics Center Volunteer Learning Center Follow Us Twitter Facebook Instagram Cancer Information, Answers, and Hope. Available Every ...

  6. Vitamin Supplements: Healthy or Hoax?

    MedlinePlus

    ... Recognition & Awards Healthy Workplace Food and Beverage Toolkit Vitamin Supplements: Healthy or Hoax? Updated:Jun 12,2015 Can vitamin and mineral supplements really make you healthier? Overwhelmed ...

  7. Opacification of Middlebrook agar as an aid in distinguishing Nocardia farcinica within the Nocardia asteroides complex.

    PubMed Central

    Carson, M; Hellyar, A

    1994-01-01

    Among 58 aerobic actinomycetes isolated from different sources and geographical locations, none of 23 Nocardia asteroides isolates, at 18 N. farcinica isolates, 1 of 5 N. otitidiscaviarum isolates, and 1 of 4 Rhodococcus species isolates opacified Middlebrook 7H10 medium. Within the N. asteroides complex, this characteristic, together with growth at 45 degrees C and resistance to each of erythromycin, cefotaxime, and tobramycin, provides a simple means of distinguishing N. farcinica from N. asteroides. PMID:7814557

  8. Effect of EDTA on Pb(II) Uptake and Translocation by Tumbleweed (Salsola Kali): Agar and Hydroponics Studies

    SciTech Connect

    de la Rosa, Guadalupe; Gardea-Torresdey, Jorge L.; Peralta-Videa, Jose R.; Aldrich, Mary

    2004-03-31

    Environmental accumulation of Pb represents a worldwide health hazard. While conventional cleanup techniques are generally expensive and soil disturbing, phytoremediation represents an inexpensive friendly option for the removal of contaminants from soil and water. In this research, tumbleweed (Salsola kali) plants exposed for 15 days to Pb(NO3)2 at 80 and 125 ppm in hydroponics and agar media, demonstrated a high capacity to uptake lead. The results showed that the plants cultivated in agar accumulated 25563, 5534 and 2185 mg Pb kg-1 DW in roots, stems and leaves, respectively. Moreover, Pb concentrations found in hydroponically grown tumbleweed plants tissues were 30744, 1511 and 1421 mg kg-1 DW in roots, stems and leaves, respectively. It was observed that EDTA enhanced Pb translocation. No Pb phytotoxic effects were observed during the experimental time period. Cellular structural features were also observed using TEM.

  9. [Clinical symptoms and circumastances of acute poisonings with fly agaric (Amanita muscaria) and panther cap (Amanita pantherina)].

    PubMed

    Łukasik-Głebocka, Magdalena; Druzdz, Artur; Naskret, Maciej

    2011-01-01

    Mushroom poisonings in Poland are quite common, especially in summer and autumn, but fly agaric (Amanita muscaria) and panther cap (Amanita pantherina) are rather rare cause of these intoxications. Fly agaric is a cause of deliberate poisoning, whereas panther cap poisoning also happens accidentally. The main toxins of these two mushrooms are ibotenic acid (pantherine, agarine), muscimol, muscazone and muscaridine. The other bioactive substances are stizolobic and stizolobinic acids and aminodicarboxyethylthiopropanoic acids. All these compounds are responsible for diverse picture of intoxication. An analysis of patients with Amanita muscaria and Amanita pantherina poisoning hospitalized in the Poznan Departament of Toxicology revealed that symptoms occurred after 30 minutes to 2 hours with vomiting, hallucinations, restlessness, increased psychomotor drive and central nervous system depression. Other antycholinergic symptoms like tachycardia and increased blood pressure, mydriasis, dry and red skin were seen only in a few cases. Acute respiratory failure was the most dangerous symptom observed in the course of poisoning.

  10. Natural occurrence and growth reaction on canavanine-glycine-bromothymol blue agar of non-neoformans Cryptococcus spp. in Malaysia.

    PubMed

    Tay, S T; Na, S L; Tajuddin, T H

    2008-11-01

    Cryptococcus albidus and C. laurentii were the predominant non-neoformans cryptococci isolated during an environmental sampling study for C. gattii at Klang Valley, Malaysia. Cryptococcus gattii was not isolated from any of the environmental samples. Cryptococcus albidus and C. laurentii were isolated mainly from vegetative samples of Eucalyptus trees and bird droppings. Upon testing on canavanine-glycine-bromothymol blue (CGB) agar, all the C. albidus isolates remained unchanged. Interestingly, a total of 29 (76.3%) C. laurentii isolates formed blue colours on the CGB agar. Sequence analysis of ITS1-5.8rDNA-ITS2 gene sequences (468 bp) of four CGB-blue C. laurentii isolates demonstrated the closest match (99%) with that of C. laurentii CBS 7140. This study demonstrated the diverse environmental niche of C. albidus and C. laurentii in Malaysia.

  11. Preparation of agar nanospheres: comparison of response surface and artificial neural network modeling by a genetic algorithm approach.

    PubMed

    Zaki, Mohammad Reza; Varshosaz, Jaleh; Fathi, Milad

    2015-05-20

    Multivariate nature of drug loaded nanospheres manufacturing in term of multiplicity of involved factors makes it a time consuming and expensive process. In this study genetic algorithm (GA) and artificial neural network (ANN), two tools inspired by natural process, were employed to optimize and simulate the manufacturing process of agar nanospheres. The efficiency of GA was evaluated against the response surface methodology (RSM). The studied responses included particle size, poly dispersity index, zeta potential, drug loading and release efficiency. GA predicted greater extremum values for response factors compared to RSM. However, real values showed some deviations from predicted data. Appropriate agreement was found between ANN model predicted and real values for all five response factors with high correlation coefficients. GA was more successful than RSM in optimization and along with ANN were efficient tools in optimizing and modeling the fabrication process of drug loaded in agar nanospheres.

  12. Solvent-tolerance of fungi located on an interface between an agar plate and an organic solvent.

    PubMed

    Oda, Shinobu; Sugitani, Ayaka; Ohashi, Shinichi

    2014-01-01

    While 6 by 20 of type culture fungi could grow on an interface between organic solvent (log P, 4.12) and agar plate, 13 by 20 of strains could form a large colony after the removal of more toxic solvent, such as styrene (log P, 2.95) and tert-butyl acetate (log P, 1.76) because of viability of spores on the interface.

  13. Morphometric and colorimetric analyses of human tumor cell line growth and drug sensitivity in soft agar culture.

    PubMed

    Alley, M C; Pacula-Cox, C M; Hursey, M L; Rubinstein, L R; Boyd, M R

    1991-02-15

    Previous studies have demonstrated the suitability of image analysis of tetrazolium-stained colonies to assess growth and drug sensitivity of human tumor cells cultivated in soft agar culture. In the present study, the potential utility of colorimetric analysis to expedite experimental drug evaluations using human tumor cell lines was investigated. The same culture dishes were assessed by image analysis and by formazan colorimetry for purposes of comparing multiple methods of measuring growth as well as growth inhibition. Replicate cultures treated with 2-(p-iodonitrophenyl)-3-p-nitrophenyl-5-phenyltetrazolium chloride or 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide exhibited nearly identical colony count and volume indices as well as excellent correlation in colorimetric end points. Colony-forming unit volume analysis versus colorimetric assessment of the same cultures following dimethyl sulfoxide extraction of protamine sulfate-rinsed, dried soft agar cultures exhibited excellent linear correlation for both growth (Pearson r ranging from 0.95 to 1.00) and drug sensitivity (Pearson r ranging from 0.90 to 0.99, and Spearman r ranging from 0.82 to 0.97) and similar drug sensitivity profiles. Results of the current investigation indicate that end points of soft agar culture remain stable for a period of at least 2 weeks following assay termination. In addition, a colorimetric detection range of 1.3-2.2 log units permits determinations of survival levels ranging from 100 to 5% of respective control levels. Colorimetric analysis is anticipated to expedite soft agar colony formation assay evaluations (a) by reducing the need to use the more rigorous and time-consuming image analysis procedures to measure activity in preliminary drug sensitivity assays and (b) by permitting the determination of effective concentration ranges of new experimental agents for subsequent, more detailed investigations.

  14. Isolation of Shiga Toxin-Producing Escherichia coli from Ground Beef Using Multiple Combinations of Enrichment Broths and Selective Agars.

    PubMed

    Brusa, Victoria; Piñeyro, Pablo E; Galli, Lucía; Linares, Luciano H; Ortega, Emanuel E; Padola, Nora L; Leotta, Gerardo A

    2016-03-01

    Shiga toxin-producing Escherichia coli (STEC) are foodborne pathogens, and beef cattle are recognized as the principal reservoir. The aims of this study were (1) to identify the most sensitive combination of selective enrichment broths and agars for STEC isolation in artificially inoculated ground beef samples, and (2) to evaluate the most efficient combination(s) of methods for naturally contaminated ground beef samples. A total of 192 ground beef samples were artificially inoculated with STEC and non-stx bacterial strains. A combination of four enrichment broths and three agars were evaluated for sensitivity, specificity, and positive predictive value for STEC isolation from experimentally inoculated samples. Enrichments with either modified tryptic soy broth (mTSB) containing 8 mg/L novobiocin (mTSB-8) or modified Escherichia coli (mEC) broth followed by isolation in MacConkey agar were the most sensitive combinations for STEC isolation of artificially inoculated samples. Independently, both enrichments media followed by isolation in MacConkey were used to evaluate ground beef samples from 43 retail stores, yielding 65.1% and 58.1% stx-positive samples by RT-PCR, respectively. No difference was observed in the isolate proportions between these two methods (8/25 [32%] and 8/28 [28.6%]). Identical serotypes and stx genotypes were observed in STEC strains isolated from the same samples by either method. In this study, no single enrichment protocol was sufficient to detect all STEC in artificially inoculated samples and had considerable variation in detection ability with naturally contaminated samples. Moreover, none of the single or combinations of multiple isolation agars used were capable of identifying all STEC serogroups in either artificially inoculated or naturally occurring STEC-contaminated ground beef. Therefore, it may be prudent to conclude that there is no single method or combination of isolation methods capable of identifying all STEC serogroups.

  15. Arthromyces and Blastosporella, two new genera of conidia-producing lyophylloid agarics (Agaricales, Basidiomycota) from the neotropics.

    PubMed

    Baroni, Timothy J; Franco-Molano, Ana Esperanza; Lodge, D Jean; Lindner, Daniel L; Horak, Egon; Hofstetter, Valerie

    2007-05-01

    Two new genera encompassing three new species of lyophylloid agarics that produce conidia on the basidiomata are described. Arthromyces is a genus comprised of two very different arthrospore-producing mushroom species found in the Greater Antilles and Central America. Blastosporella is a monotypic genus with spherical balls of blastospores covering the pileus surface with age and is known from Hispaniola and Colombia. A key to the species of Arthromyces is included.

  16. Inoculation Efficacy of the Medium Used for Suspension of Puccinia hemerocallidis Urediniospores

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A susceptible daylily (Hemerocallis spp.) ‘Pardon Me’ was inoculated with Puccinia hemerocallidis. Urediniospores were suspended in liquid media (deionized water, mineral oil, 0.1% agar, 0.1% agar plus 0.125% Tween 20, 0.1% agar plus Nu-Film® 17, 0.1% agar plus Bio-90™, and 0.1% agar made with buff...

  17. Irradiation of silver and agar/silver nanoparticles with argon, oxygen glow discharge plasma, and mercury lamp.

    PubMed

    Ahmad, Mahmoud M; Abdel-Wahab, Essam A; El-Maaref, A A; Rawway, Mohammed; Shaaban, Essam R

    2014-01-01

    The irradiation effect of argon, oxygen glow discharge plasma, and mercury lamp on silver and agar/silver nanoparticle samples is studied. The irradiation time dependence of the synthesized silver and agar/silver nanoparticle absorption spectra and their antibacterial effect are studied and compared. In the agar/silver nanoparticle sample, as the irradiation time of argon glow discharge plasma or mercury lamp increases, the peak intensity and the full width at half maximum, FWHM, of the surface plasmon resonance absorption band is increased, however a decrease of the peak intensity with oxygen glow plasma has been observed. In the silver nanoparticle sample, as the irradiation time of argon, oxygen glow discharge plasma or mercury lamp increases, the peak intensity of the surface plasmon resonance absorption band is increased, however, there is no significant change in the FWHM of the surface plasmon resonance absorption band. The SEM results for both samples showed nanoparticle formation with mean size about 50 nm and 40 nm respectively. Throughout the irradiation time with the argon, oxygen glow discharge plasma or mercury lamp, the antibacterial activity of several kinds of Gram-positive and Gram-negative bacteria has been examined.

  18. Reliability of the agar based method to assess the production of degradative enzymes in clinical isolates of Candida albicans.

    PubMed

    Arantes, Paula Tamião; Sanitá, Paula Volpato; Santezi, Carolina; Barbeiro, Camila de Oliveira; Reina, Bárbara Donadon; Vergani, Carlos Eduardo; Dovigo, Lívia Nordi

    2016-03-01

    The aim of this study was to establish a reproducible protocol using the methodology of hyaline zones around the colonies on specific agar plates for phospholipase and proteinase production. This was an in vitro double-blind experiment, in which the dependent variables were the enzymatic activity measurements (Pz) for the production of phospholipase (Pz-ph) and the production of secreted aspartyl proteinases (Pz-sap). Three independent variables give rise to different measurement protocols. All measurements were carried out at two different moments by four examiners (E1, E2, E3, and E4). The minimum sample size was 30 Candida albicans clinical isolates. Specific agar plates for phospholipase and SAPs production were prepared according the literature. The intra-and inter-examiner reproducibility for each protocol was estimated using the Intraclass Correlation Coefficient (ICC) and its confidence interval (95% CI). Based on the results obtained for both phospholipase and SAPs, there appears to be no consensus on the protocol chosen for each particular examiner. Measuring the colonies in triplicate may be the main factor associated with the increase in measurement accuracy and should therefore take precedence over measuring only one colony. When only one examiner is responsible for taking measurements, a standard protocol should be put in place and the statistical calibration of this researcher should be done prior to data collection. However, if two or more researchers are involved in the assessment of agar plates, our results suggest that the protocols using software to undertake plate reading is preferred.

  19. Metronidazole susceptibility testing for Helicobacter pylori: comparison of disk, broth, and agar dilution methods and their clinical relevance.

    PubMed Central

    DeCross, A J; Marshall, B J; McCallum, R W; Hoffman, S R; Barrett, L J; Guerrant, R L

    1993-01-01

    Since the methods for metronidazole susceptibility testing of Helicobacter pylori have not been standardized or validated, we compared three methods that are used to test the metronidazole susceptibilities of 25 isolates of H. pylori. Specifically, we examined the methods of Steer's replicator agar dilution, tube broth microdilution, and modified Kirby-Bauer disk diffusion. The metronidazole disk zone sizes obtained by the disk diffusion method correlated well (r = 0.74) with the MICs obtained by the agar dilution method. Afterward, the disk diffusion method was used to characterize the metronidazole susceptibilities of 44 isolates of H. pylori. Dual therapy (bismuth and metronidazole) proved to be highly effective against metronidazole-susceptible strains (81.6% eradication rate) but fared poorly against resistant strains (16.7% eradication rate; P < 0.01). Using agar dilution testing, we validated the modified Kirby-Bauer disk diffusion method for metronidazole susceptibility testing of H. pylori and conclude that it is practical, accurate, and clinically applicable. PMID:8370723

  20. Measurement of human tumour cell growth in soft-agar cultures using computer-assisted volume analysis.

    PubMed Central

    Alley, M. C.; Lieber, M. M.

    1985-01-01

    Growth in soft-agar bilayer cultures of human tumour cells derived from 4 in vitro continuous cell lines, from 21 xenografts carried in athymic mice, and from 197 samples of fresh human solid tumours of various histologic types was analyzed by computer-assisted image analysis. Replicate cultures for each specimen were assessed on successive days of incubation for the number and volume of growth units within multiple size categories. Our results confirm the recent finding of others that there is an upper limit of approximately 10(9) microns 3 to the cumulative growth unit volume obtainable in a 2 ml bilayer soft agar culture system. Since this upper limit to the carrying capacity of the closed culture system exists, the extent of growth within the cultures is determined in a fundamental way by the cumulative volume of growth units initially inoculated into cultures. A growth index of greater than or equal to 16-fold was only seen when initial cumulative growth unit volume was less than 10(7) microns 3 per culture dish. Computer-assisted volume analysis (CAVA) appears to be a useful quantitative method to study the growth of human tumour cells in soft agar cultures. PMID:4027164

  1. Mechanical touch responses of Arabidopsis TCH1-3 mutant roots on inclined hard-agar surface

    NASA Astrophysics Data System (ADS)

    Zha, Guodong; Wang, Bochu; Liu, Junyu; Yan, Jie; Zhu, Liqing; Yang, Xingyan

    2016-01-01

    The gravity-induced mechanical touch stimulus can affect plant root architecture. Mechanical touch responses of plant roots are an important aspect of plant root growth and development. Previous studies have reported that Arabidopsis TCH1-3 genes are involved in mechano-related events, how-ever, the physiological functions of TCH1-3 genes in Arabidopsis root mechanoresponses remain unclear. In the present study, we applied an inclined hard agar plate method to produce mechanical touch stimulus, and provided evidence that altered mechanical environment could influence root growth. Furthermore, tch1-3 Arabidopsis mutants were investigated on inclined agar surfaces to explore the functions of TCH1-3 genes on Arabidopsis root mechanoresponses. The results showed that two tch2 mutants, cml24-2 and cml24-4, exhibited significantly reduced root length, biased skewing, and decreased density of lateral root. In addition, primary root length and density of lateral root of tch3 (cml12-2) was significantly decreased on inclined agar surfaces. This study indicates that the tch2 and tch3 mutants are hypersensitive to mechanical touch stimulus, and TCH2 (CML24-2 and CML24-4) and TCH3 (CML12-2) genes may participate in the mechanical touch response of Arabidopsis roots.

  2. Nutrient limitation leads to penetrative growth into agar and affects aroma formation in Pichia fabianii, P. kudriavzevii and Saccharomyces cerevisiae.

    PubMed

    van Rijswijck, Irma M H; Dijksterhuis, Jan; Wolkers-Rooijackers, Judith C M; Abee, Tjakko; Smid, Eddy J

    2015-01-01

    Among fermentative yeast species, Saccharomyces cerevisiae is most frequently used as a model organism, although other yeast species may have special features that make them interesting candidates to apply in food-fermentation processes. In this study, we used three yeast species isolated from fermented masau (Ziziphus mauritiana) fruit, S. cerevisiae 131, Pichia fabianii 65 and Pichia kudriavzevii 129, and determined the impact of nitrogen and/or glucose limitation on surface growth mode and the production of volatile organic compounds (VOCs). All three species displayed significant changes in growth mode in all nutrient-limited conditions, signified by the formation of metafilaments or pseudohyphae. The timing of the transition was found to be species-specific. Transition in growth mode is suggested to be linked to the production of certain fusel alcohols, such as phenylethyl alcohol, which serve as quorum-sensing molecules. Interestingly, we did not observe concomitant increased production of phenylethyl alcohol and filamentous growth. Notably, a broader range of esters was found only for the Pichia spp. grown on nitrogen-limited agar for 21 days compared to nutrient-rich agar, and when grown on glucose- and glucose- plus nitrogen-limited agar. Our data suggest that for the Pichia spp., the formation of esters may play an important role in the switch in growth mode upon nitrogen limitation. Further biological or ecological implications of ester formation are discussed.

  3. Beyond Agar: Gel Substrates with Improved Optical Clarity and Drug Efficiency and Reduced Autofluorescence for Microbial Growth Experiments

    PubMed Central

    McElfresh, Cameron; Wong, Lily R.

    2015-01-01

    Agar, a seaweed extract, has been the standard support matrix for microbial experiments for over a century. Recent developments in high-throughput genetic screens have created a need to reevaluate the suitability of agar for use as colony support, as modern robotic printing systems now routinely spot thousands of colonies within the area of a single microtiter plate. Identifying optimal biophysical, biochemical, and biological properties of the gel support matrix in these extreme experimental conditions is instrumental to achieving the best possible reproducibility and sensitivity. Here we systematically evaluate a range of gelling agents by using the yeast Saccharomyces cerevisiae as a model microbe. We find that carrageenan and Phytagel have superior optical clarity and reduced autofluorescence, crucial for high-resolution imaging and fluorescent reporter screens. Nutrient choice and use of refined Noble agar or pure agarose reduce the effective dose of numerous selective drugs by >50%, potentially enabling large cost savings in genetic screens. Using thousands of mutant yeast strains to compare colony growth between substrates, we found no evidence of significant growth or nutrient biases between gel substrates, indicating that researchers could freely pick and choose the optimal gel for their respective application and experimental condition. PMID:26070672

  4. Choline chloride based ionic liquid analogues as tool for the fabrication of agar films with improved mechanical properties.

    PubMed

    Sousa, Ana M M; Souza, Hiléia K S; Latona, Nicholas; Liu, Cheng-Kung; Gonçalves, Maria P; Liu, LinShu

    2014-10-13

    In the present paper, we test the suitability of ChCl/urea (DES-U) and ChCl/glycerol (DES-G) eutectic mixtures, each one prepared at 1:2 molar ratio, for the production of agar films. A three-step process is proposed: pre-solubilization of polymer in DES followed by compression-molding and subsequent drying. The mechanical properties, water resistance and microstructure of the films were evaluated at different polymer concentrations (i.e. 2-6%, w/w). DES-U showed by far, the best film forming ability. Agreeing with the diffusion and SEM data, films with the best mechanical properties were found at the lowest and highest agar concentrations (tensile strengths of 24.2-42 MPa and elongations of 15.4-38.9%). The water sorption and contact angle studies suggested increased hydrophilicity for the film containing the lowest concentration of agar. The use of choline chloride based ionic liquid analogues as solvent and plasticizer might be a promising tool for the development of new non-aqueous materials based on seaweed polysaccharides.

  5. Evaluation of Trans-Vag Broth, Colistin-Nalidixic Agar, and CHROMagar StrepB for Detection of Group B Streptococcus in Vaginal and Rectal Swabs from Pregnant Women in South Africa

    PubMed Central

    Kwatra, Gaurav; Madhi, Shabir A.; Cutland, Clare L.; Buchmann, Eckhart J.

    2013-01-01

    Maternal vaginal colonization with group B streptococcus (GBS) is a major risk factor for invasive GBS infection in newborns. The CDC-recommended method for detecting GBS colonization is to culture vaginal and rectal swabs in a selective broth followed by subculture on blood agar or a selective medium. A high incidence of antimicrobial resistance in the fecal microflora can compromise the recovery of GBS from the selective broth. Here, we compared CHROMagar StrepB (CA), Columbia colistin-nalidixic agar (CNA), and Trans-Vag selective broth enrichment for the isolation of GBS from 130 vaginal and 130 rectal swabs from pregnant women. The swabs were randomized for plating first on either CA or CNA, and they then were inoculated in Trans-Vag broth. GBS was cultured from 37.7% of the vaginal swabs and 33.1% of the rectal swabs. There were no differences in the detection rates for the vaginal swabs between CA (31.5%), CNA (26.2%), and the selective broth (30.0%). The sensitivities in relation to a composite score were 83.7%, 69.4%, and 79.6%, respectively. However, recovery of GBS from the rectal swabs was significantly higher from CA (29.2%; P < 0.0001) and CNA (23.8%; P = 0.002) than from the selective broth (9.2%). The sensitivities were 88.4%, 72.1%, and 27.9%, respectively. The order of plating on the solid medium was significant (P = 0.003), with GBS detection rates of 30.8% and 24.6% when swabs were plated first and second, respectively. These findings show that a selective broth is not suitable for the recovery of GBS from rectal swabs in settings such as ours, due to masking of the GBS colonies by persistent microflora. PMID:23698527

  6. GlutaMAX prolongs the shelf life of the culture medium for porcine parthenotes.

    PubMed

    Zhao, Ming-Hui; Kim, Nam-Hyung; Cui, Xiang-Shun

    2016-02-01

    In vitro porcine embryo production systems have been established and well characterized. However, the efficiency of embryo development during IVC is still very low. In the present study, we have investigated the development of parthenogenetic porcine embryos in the well-known PZM-5 medium for porcine embryos, which was modified by replacing glutamine with the GlutaMAX supplement. We revealed that blastocyst apoptosis was significantly lower in the presence of GlutaMAX, which reduced the release of mitochondrial cytochrome c. Furthermore, the expression of apoptosis genes was significantly lower during GlutaMAX treatment (P < 0.05). The modified medium was also examined for the eventual loss of its efficacy in the presence of GlutaMAX. Three, 6, and 12 months after medium preparation, blastocyst formation in the GlutaMAX-supplemented medium was significantly higher than the number of blastocysts in the medium containing glutamine. After a long period of storage, ammonia concentration was significantly increased in the glutamine medium, whereas it was not statistically different in the GlutaMAX medium. Elevated ammonia concentrations reduced the mitochondrial membrane potential and ATP content of blastocysts in the glutamine medium. These results demonstrate that GlutaMAX can reduce blastocyst apoptosis via inhibition of the cytochrome c pathway and significantly extend the shelf life of the culture medium to at least 1 year.

  7. Addition of Carbon to the Culture Medium Improves the Detection Efficiency of Aflatoxin Synthetic Fungi

    PubMed Central

    Suzuki, Tadahiro; Iwahashi, Yumiko

    2016-01-01

    Aflatoxin (AF) is a harmful secondary metabolite that is synthesized by the Aspergillus species. Although AF detection techniques have been developed, techniques for detection of AF synthetic fungi are still required. Techniques such as plate culture methods are continually being modified for this purpose. However, plate culture methods require refinement because they suffer from several issues. In this study, activated charcoal powder (carbon) was added to a culture medium containing cyclodextrin (CD) to enhance the contrast of fluorescence and improve the detection efficiency for AF synthetic fungi. Two culture media, potato dextrose agar and yeast extract sucrose agar, were investigated using both plate and liquid cultures. The final concentrations of CD and carbon in the media were 3 mg/mL and 0.3 mg/mL, respectively. Addition of carbon improved the visibility of fluorescence by attenuating approximately 30% of light scattering. Several fungi that could not be detected with only CD in the medium were detected with carbon addition. The carbon also facilitated fungal growth in the potato dextrose liquid medium. The results suggest that addition of carbon to media can enhance the observation of AF-derived fluorescence. PMID:27854283

  8. [ERGOGENIC SPORT SUPPLEMENTS FOR ATHLETES].

    PubMed

    Arieli, Rakefet; Lahav, Yair

    2016-06-01

    Use of performance-enhancing supplements occurs at all levels of sports, from recreational athletes to professional athletes. Although some supplements do enhance athletic performance, many have no proven benefits and have adverse effects. Nutritional supplements are categorized into the following categories: I. Apparently Effective. II. Possibly Effective. III. Too Early To Tell. IV. Apparently Ineffective. This article will review 4 ergogenic supplements which are categorized in the first category--"Apparently Effective"--1) Buffer agents 2) Creatine 3) Caffeine and 4 Nitric Oxide. Given the widespread use of performance enhancing supplements, physicians, and dietitians should be prepared to counsel athletes about their effectiveness, safety and legality.

  9. Effective Nutritional Supplement Combinations

    NASA Astrophysics Data System (ADS)

    Cooke, Matt; Cribb, Paul J.

    Few supplement combinations that are marketed to athletes are supported by scientific evidence of their effectiveness. Quite often, under the rigor of scientific investigation, the patented combination fails to provide any greater benefit than a group given the active (generic) ingredient. The focus of this chapter is supplement combinations and dosing strategies that are effective at promoting an acute physiological response that may improve/enhance exercise performance or influence chronic adaptations desired from training. In recent years, there has been a particular focus on two nutritional ergogenic aids—creatine monohydrate and protein/amino acids—in combination with specific nutrients in an effort to augment or add to their already established independent ergogenic effects. These combinations and others are discussed in this chapter.

  10. Isolation on Chocolate Agar Culture of Legionella pneumophila Isolates from Subcutaneous Abscesses in an Immunocompromised Patient

    PubMed Central

    Cavalie, Laurent; Daviller, Benjamin; Dubois, Damien; Mantion, Benoît; Delobel, Pierre; Debard, Alexa; Prere, Marie-Françoise; Marchou, Bruno; Martin-Blondel, Guillaume

    2015-01-01

    Cutaneous infections due to Legionella species have rarely been reported (L. J. Padrnos, J. E. Blair, S. Kusne, D. J. DiCaudo, and J. R. Mikhael, Transpl Infect Dis 16:307–314, 2014; P. W. Lowry, R. J. Blankenship, W. Gridley, N. J. Troup, and L. S. Tompkins, N Engl J Med 324:109–113, 1991; M. K. Waldor, B. Wilson, and M. Swartz, Clin Infect Dis 16:51–53, 1993). Here we report the identification of Legionella pneumophila isolates, from subcutaneous abscesses in an immunocompromised patient, that grew in an unusual medium for Legionella bacteria. PMID:26292305

  11. Isolation on Chocolate Agar Culture of Legionella pneumophila Isolates from Subcutaneous Abscesses in an Immunocompromised Patient.

    PubMed

    Barigou, Mohammed; Cavalie, Laurent; Daviller, Benjamin; Dubois, Damien; Mantion, Benoît; Delobel, Pierre; Debard, Alexa; Prere, Marie-Françoise; Marchou, Bruno; Martin-Blondel, Guillaume

    2015-11-01

    Cutaneous infections due to Legionella species have rarely been reported (L. J. Padrnos, J. E. Blair, S. Kusne, D. J. DiCaudo, and J. R. Mikhael, Transpl Infect Dis 16:307-314, 2014; P. W. Lowry, R. J. Blankenship, W. Gridley, N. J. Troup, and L. S. Tompkins, N Engl J Med 324:109-113, 1991; M. K. Waldor, B. Wilson, and M. Swartz, Clin Infect Dis 16:51-53, 1993). Here we report the identification of Legionella pneumophila isolates, from subcutaneous abscesses in an immunocompromised patient, that grew in an unusual medium for Legionella bacteria.

  12. Supplementation patterns in marathon runners.

    PubMed

    Nieman, D C; Gates, J R; Butler, J V; Pollett, L M; Dietrich, S J; Lutz, R D

    1989-11-01

    The purpose of the present investigation was to study the use of supplements in a large group of endurance runners (no. = 347) who had participated in the 1987 Los Angeles Marathon. Three-day dietary records were analyzed for nutrient content and supplement usage. The runners' supplementation patterns with respect to demographics, dietary quality, training habits, and race performance were investigated. In general, no significant associations were found between supplement use and the aforementioned variables. Use of supplements, especially vitamins C and E, calcium, and zinc, increased with age (p less than .05). Daily use of at least one type of supplement was reported by 29% of the runners; 48% reported use of at least one type of supplement within the 3-day period.

  13. Oxidative burst induced pseudosclerotium formation of Morchella steppicola Zerova on different malt agar media.

    PubMed

    Király, I; Czövek, P

    2007-08-01

    Morchella steppicola Zerova mycelia was grown on modified MS (MSK) medium and on MSK medium containing different malt content. Starvation induced an enhanced pseudosclerotium formation in a given zone of the culture. The malondialdehyde content of the mycelium at the site of pseudosclerotium formation was related to the acceleration of lipid peroxidation and oxidative stress. Superoxide dismutase activity was monitored in control and stressed vegetative hyphae subjected to malt withdrawal. In the formation zone of resting bodies, an enhanced oxidative burst was observed. The glucose and trehalose contents of M. steppicola mycelium during pseudosclerotium formation were also investigated. The glucose concentration of the mycelia approached a minimum during pseudosclerotium formation. At the same time, trehalose concentration reached a maximum in the zone of pseudosclerotium formation. The dry mass of mycelia in these zones was higher than average. The dry matter content of the pseudosclerotium-forming zones significantly exceeded the average of the whole culture. The correlation among trehalose accumulation, oxidative burst, and pseudosclerotium formation was clearly demonstrated.

  14. Conditions for growing Mycoplasma canadense and Mycoplasma verecundum in a serum-free medium.

    PubMed

    Muñoz, G; Sotomayor, P

    1990-07-01

    Mycoplasma canadense and Mycoplasma verecundum were cultured in a serum-free medium containing bovine serum albumin, cholesterol, oleic acid, and palmitic acid in order to avoid the addition of horse serum. Growth was detected by measurement of A640 and by colony formation. The level of growth attained in this medium was less than that obtained in the horse serum-supplemented media, but colonies retained their distinctive morphology.

  15. Conditions for growing Mycoplasma canadense and Mycoplasma verecundum in a serum-free medium.

    PubMed Central

    Muñoz, G; Sotomayor, P

    1990-01-01

    Mycoplasma canadense and Mycoplasma verecundum were cultured in a serum-free medium containing bovine serum albumin, cholesterol, oleic acid, and palmitic acid in order to avoid the addition of horse serum. Growth was detected by measurement of A640 and by colony formation. The level of growth attained in this medium was less than that obtained in the horse serum-supplemented media, but colonies retained their distinctive morphology. Images PMID:2202260

  16. Iron supplementation for the control of iron deficiency in populations at risk.

    PubMed

    Viteri, F E

    1997-06-01

    Iron supplementation, mostly with a therapeutic orientation, has been a key strategy for the short-term control of iron deficiency and ferropenic anemia. It has been used almost exclusively in antenatal clinics, but in spite of its confirmed efficacy in supervised trials, it has proven ineffective in practice in most developing countries. Poor effectiveness has been attributed to various factors including insufficient dose and time of supplementation and poor adherence. These problems have led to the administration of high iron doses, which have proven equally ineffective in practice. This paper introduces four concepts: (1) that iron supplementation targeted to pregnant women should cover the full reproductive cycle, from prepregnancy to at least the end of lactation instead of only the pregnant women; (2) that entering pregnancy with iron deficiency contributes to the failure of antenatal iron supplementation and that prepregnancy iron reserves increase the effectiveness of antenatal supplementation; (3) that medium- to long-term weekly ingestion of proper iron-folate supplements, with a preventive aim and directed to all risk groups, should be community based rather than health service based but supervised by the latter (in this sense, preventive supplementation is equal to targeted iron fortification); and (4) that preventive supplementation, based on weekly dosing, has proven efficacious. Problem-oriented research to evaluate the sustainability and medium- to long-term efficacy of these concepts is called for. The bases for the concepts and suggestions are summarized in this paper.

  17. CHROMagar Candida, a new differential isolation medium for presumptive identification of clinically important Candida species.

    PubMed Central

    Odds, F C; Bernaerts, R

    1994-01-01

    CHROMagar Candida is a novel, differential culture medium that is claimed to facilitate the isolation and presumptive identification of some clinically important yeast species. We evaluated the use of this medium with 726 yeast isolates, including 82 isolated directly on the medium from clinical material. After 2 days of incubation at 37 degrees C, 285 C. albicans isolates gave distinctive green colonies that were not seen with any of 441 other yeast isolates representing 21 different species. A total of 54 C. tropicalis isolates also developed distinctive dark blue-gray colonies with a halo of dark brownish purple in the surrounding agar. C. krusei isolates (n = 43) also formed highly characteristic rough, spreading colonies with pale pink centers and a white edge that was otherwise encountered only rarely with isolates of C. norvegensis. Trichosporon spp. (n = 34) formed small, pale colonies that became larger and characteristically rough with prolonged incubation. Most of the other 310 yeasts studied formed colonies with a color that ranged from white to pink to purple with a brownish tint. The only exceptions were found among isolates identified as Geotrichum sp. or Pichia sp., some of which formed colonies with a gray to blue color and which in two instances formed a green pigment or a dark halo in the agar. The specificity and sensitivity of the new medium for the presumptive identification of C. albicans, C. krusei, and C. tropicalis exceeded 99% for all three species. A blinded reading test involving four personnel and 57 yeast isolates representing nine clinically important species confirmed that colonial appearance after 48 h of incubation on CHROMagar Candida afforded the correct presumptive recognition of C. albicans, C. tropicalis, C, krusei, and Trichosporon spp. None of nine bacterial isolates grew on CHROMagar Candida within 72 h, and bacteria (Escherichia coli) grew from only 4 of 104 vaginal, 100 oral, and 99 anorectal swabs. The new medium

  18. Fluorogenic selective and differential medium for isolation of fecal streptococci.

    PubMed Central

    Littel, K J; Hartman, P A

    1983-01-01

    Of 44 fluorogenic substrates tested for their ability to differentiate species of fecal streptococci, four yielded species-differentiating reactions. The remaining substrates either yielded uniformly positive, negative, or variable strain-dependent reactions. One substrate, 4-methylumbelliferone-alpha-D-galactoside, was hydrolyzed by Streptococcus bovis and S. faecium and its biotypes. 4-Methylumbelliferone-alpha-D-galactoside and a colorimetric starch substrate were incorporated into the fecal streptococcal selective medium of Donnelly and Hartman (Appl. Environ. Microbiol. 35:576-581, 1978). Three phenotypic groups were identifiable on the new fluorescent gentamicin-thallous-carbonate agar: (i) starch hydrolysis and fluorescence (S. bovis), (ii) no starch hydrolysis but fluorescence (S. faecium and its biotypes), and (iii) no starch hydrolysis or fluorescence (S. faecalis, S. avium, S. equinus, S. mitis, and S. salivarius). Of the presumptive identifications from sewage, swine, and bovine samples, 86% were confirmed as being correct. The new medium has potential application in water, food, environmental, and possibly clinical microbiology. Images PMID:6830220

  19. New medium licensed for campylobacter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A medium, “Campy-Cefex”, has been licensed by the ARS Office of Technology Transfer with Becton Dickinson (No. 1412-002) and Neogen (No. 1412-001) based on patent No. 5,891,709, “Campy-Cefex Selective and Differential Medium for Campylobacter” by Dr. Norman Stern of the Poultry Microbiological Safet...

  20. Long-term in vitro culture of bovine preantral follicles: Effect of base medium and medium replacement methods.

    PubMed

    Araújo, V R; Gastal, M O; Wischral, A; Figueiredo, J R; Gastal, E L

    2015-10-01

    Two culture media and replacement methods were compared during long-term in vitro culture of secondary follicles of cattle using α-MEM(+) or TCM-199(+) as base media. The medium replacement methods were: Conventional - removal and subsequent addition of the same amount (60μl) in a 100μl aliquot (MEM-C and TCM-C), and Small Supplementation - addition of 5μl of fresh medium to an initial small aliquot (50μl), resulting in a final volume of 125μl on the last day of culture (MEM-S and TCM-S). A total of 207 secondary follicles were cultured individually for 32 days at 38.5°C in 5% CO2 and medium replacement was performed every other day. The MEM-S treatment resulted in a larger (P<0.01) follicular diameter, greater (P<0.02) growth rate, greater (P<0.02) antrum formation, as well as greater (P<0.0001) estradiol concentrations when compared with the MEM-C treatment. The medium change methods did not affect (P>0.05) the follicular and estradiol end points for TCM-199(+). The expression of the FSHR gene was greater (P<0.03) with the TCM-C than TCM-S treatment, while the relative amounts of mRNA for IGF1 was greater (P<0.02) with MEM-S than TCM-S treatments and for VEGF was greater (P<0.02) with MEM-C than TCM-C treatment. In conclusion, the type of base medium and the effect of periodic addition of medium differentially affected follicle development, estradiol production, and gene expression. Furthermore, α-MEM(+) can be used to replace TCM-199(+) for culture of preantral follicles of cattle if progressive addition of medium is used for medium change.

  1. Supplementing national menu labeling.

    PubMed

    Hodge, James G; White, Lexi C

    2012-12-01

    The US Food and Drug Administration's forthcoming national menu labeling regulations are designed to help curb the national obesity epidemic by requiring calorie counts on restaurants' menus. However, posted calories can be easily ignored or misunderstood by consumers and fail to accurately describe the healthiness of foods. We propose supplemental models that include nutritional information (e.g., fat, salt, sugar) or specific guidance (e.g., "heart-healthy" graphics). The goal is to empower restaurant patrons with better data to make healthier choices, and ultimately to reduce obesity prevalence.

  2. Hyperkalemia from Dietary Supplements

    PubMed Central

    Villgran, Vipin

    2016-01-01

    Hyperkalemia is a common electrolyte problem in patients with chronic kidney disease. It is typically caused by medications in patients with poor kidney function. Patients with comorbodities such as heart failure and diabetes are predisposed to electrolyte problems. Salt substitutes and dietary supplements are uncommon causes of hyperkalemia, but we propose that they are under-recognized and underdiagnosed causes in patients with chronic kidney disease. Our case report and literature review illustrates that a careful dietary history is essential in patients presenting with electrolyte disorders, especially hyperkalemia. PMID:27924248

  3. Supplementing managed competition.

    PubMed

    Higgins, W

    President Clinton's proposal for health care reform calls for managed competition within global expenditure targets. However, it is unlikely that health plans will have sufficient leverage with providers to negotiate arrangements consistent with expenditure targets in nonurban areas. This paper describes a reimbursement system based on competitive prospective payment and capitation (CPPC) which can supplement managed competition in less populous areas or replace managed competition should that strategy prove unsuccessful. The CPPC system is capable of enforcing an expenditure target while encouraging the formation of capitated networks and creating strong incentives for efficiency. It is generally compatible with the Clinton administration's version of managed competition.

  4. Special Supplement Introduction: Hallucinations

    PubMed Central

    Fernyhough, Charles; Waters, Flavie

    2014-01-01

    This Special Supplement presents reports from 11 working groups of the interdisciplinary International Consortium on Hallucination Research meeting in Durham, UK, September 2013. Topics include psychological therapies for auditory hallucinations, culture and hallucinations, hallucinations in children and adolescents, visual hallucinations, interdisciplinary approaches to the phenomenology of auditory verbal hallucinations (AVHs), AVHs in persons without need for care, a multisite study of the PSYRATS instrument, subtypes of AVHs, the Hearing Voices Movement, Research Domain Criteria for hallucinations, and cortical specialization as a route to understanding hallucinations. PMID:24936079

  5. Enhanced catalytic efficiency of endo-β-agarase I by fusion of carbohydrate-binding modules for agar prehydrolysis.

    PubMed

    Alkotaini, Bassam; Han, Nam Soo; Kim, Beom Soo

    2016-11-01

    Recently, Microbulbifer thermotolerans JAMB-A94 endo-β-agarase I was expressed as catalytic domain (GH16) without a carbohydrate-binding module (CBM). In this study, we successfully constructed different fusions of GH16 with its original CBM6 and CBM13 derived from Catenovulum agarivorans. The optimum temperature and pH for fusions GH16-CBM6, GH16-CBM13, GH16-CBM6-CBM13 and GH16-CBM13-CBM6 were similar to GH16, at 55°C and pH 7. All the constructed fusions significantly enhanced the GH16 affinity (Km) and the catalytic efficiency (Kcat/Km) toward agar. Among them, GH16-CBM6-CBM13 exhibited the highest agarolytic activity, for which Km decreased from 3.67 to 2.11mg/mL and Kcat/Km increased from 98.6 (mg/mL)(-1)sec(-1) to 400.6 (mg/mL)(-1)sec(-1). Moreover, all fusions selectively increased GH16 binding ability to agar, in which the highest binding ability of 95% was obtained with fusion GH16-CBM6-CBM13. Melted agar was prehydrolyzed with GH16-CBM6-CBM13, resulting in a degree of liquefaction of 45.3% and reducing sugar yield of 14.2%. Further addition of Saccharophagus degradans agarolytic enzymes resulted in mono-sugar yields of 35.4% for galactose and 31.5% for 3,6-anhydro-l-galactose. There was no pH neutralization step required and no 5-hydroxymethylfurfural detected, suggesting the potential of a new enzymatic prehydrolysis process for efficient production of bio-products such as biofuels.

  6. Use of urease-bromothymol blue-agar method for large-scale testing of urine on grain and seeds.

    PubMed

    Valdes, P A; Ziobro, G C; Ferrera, R S

    1996-01-01

    The current AOAC method (963.28) for large-scale (50 g) testing of urine on grain is based on the reaction of sodium in urine with magnesium uranyl acetate. Detection of sodium suggests that urine is present and that a test for urea is appropriate. Urea is detected with urease-bromothymol blue-paper and is confirmed through its reaction with xanthydrol to form dixanthylurea crystals, which are detected microscopically. The initial nonspecific test for sodium can be influenced by the presence of salt or other sodium compounds. Furthermore, the magnesium uranyl acetate spray used in Method 963.28 potentially exposes the analyst to the aerosol of a volatile, toxic uranium compound. Excess reagents and analyzed test portions must be disposed of as radioactive waste. In addition, Method 963.28 requires several steps to determine the presence of urea. The alternative AOAC method (972.41) tests for the presence of urea from urine on individual seeds. Urea is enzymatically decomposed to ammonia and carbon dioxide by urease. Liberated ammonia shifts the pH, changing the color of the indicator in the agar from yellow to blue. This study adapts Method 972.41 to larger test samples. Up to 25 g grains and seeds are sprayed with urease test agar instead of being individually immersed in the urease test agar. The modified method was used to analyze urea on seeds and grains of 24 plants from 4 families. The method has a limit of detection of one seed contaminated with 1 microgram urea.

  7. Antimicrobial Activity of Endodontic Medicaments and Vehicles using Agar Well Diffusion Method on Facultative and Obligate Anaerobes

    PubMed Central

    Bhat, Kishore G; Sogi, Suma

    2016-01-01

    Aims The aim of this study was to determine the relative antimicrobial effectiveness of these endodontic medicaments and various vehicles using an agar well diffusion assay. Materials and methods Double Antibiotic Paste(DAP), modified DAP, 2% Chlorhexidine gluconate and their combination with four vehicles namely Polyethylene glycol 400 (PEG), Propylene glycol (PG), combinations of PG with PEG and lastly Glycerine were tested using agar well diffusion assay. The minimum bactericidal concentration was noted against four standard strains of organisms ie Streptococcus mutans ATCC( American Type Culture Collection) 25175, Staphylococcus aureus ATCC 12598, Enterococcus faecalis ATCC 35550 and Eschericia coli ATCC 25922. Successful endodontic therapy depends upon thorough disinfection of root canals. In some refractory cases, routine endodontic therapy is not sufficient, so intracanal medicaments are used for proper disinfection of canals. Issues of resistance, limited spectrum of activity and lack of antifungal properties, the hunt for the ideal intracanal medicament continues. In this regard, the vehicles used to form the pastes play a supportive role by forming the appropriate consistency for placement and may dramatically influence their chemical characteristics like their solubility and diffusion. Thus, inorder to use safer and equally effective intracanal medicaments, Chlorhexidine gluconate is being unveiled in this study. Results The difference between the four vehicles when combined with the same endodontic medicament studied above is nonsignificant (NS) except against Porphyromonas gingivalis. Propylene glycol is significantly effective than Glycerine when used with DAP ie C+M medicament combination. (p = 0.029) Conclusion 2% chlorhexidine gluconate and modified DAP can definitely replace DAP and triple antibiotic paste as end-odontic medicaments with chlorhexidine having an added advantage of bactericidal action, substantivity, biocompatibility, low toxicity

  8. Inaccuracy of the disk diffusion method compared with the agar dilution method for susceptibility testing of Campylobacter spp.

    PubMed

    Lehtopolku, Mirva; Kotilainen, Pirkko; Puukka, Pauli; Nakari, Ulla-Maija; Siitonen, Anja; Eerola, Erkki; Huovinen, Pentti; Hakanen, Antti J

    2012-01-01

    The agar dilution method has been standardized by the CLSI for the susceptibility testing of Campylobacter species, and according to these standards, the disk diffusion method should be used only in screening for macrolide and ciprofloxacin resistance. Nevertheless, the disk diffusion test is currently widely used, since it is easy to perform in clinical microbiology laboratories. In this study, the disk diffusion method was compared to the agar dilution method by analyzing the in vitro activities of seven antimicrobial agents against 174 Campylobacter strains collected in Finland between 2003 and 2008. Recommendations of the CLSI were followed using Mueller-Hinton agar plates with 5% of sheep blood. For each strain, the disk diffusion tests were performed two to four times. Of the 33 erythromycin-resistant strains (MIC, ≥16 μg/ml), 24 (73%) constantly showed a 6-mm erythromycin inhibition zone (i.e., no inhibition), while for seven strains the inhibition zone varied from 6 to 44 mm in repeated measurements. Among the 141 erythromycin-susceptible strains (MIC, <16 μg/ml), erythromycin inhibition zones varied between 6 and 61 mm. Of the 87 ciprofloxacin-resistant strains, 47 (54%) showed 6-mm inhibition zones, while 40 strains showed inhibition zones between 6 and 60 mm. Significant differences between the repetitions were observed in the disk diffusion for all antimicrobial agents and all strains except for the macrolide-resistant strains regarding the macrolides. For 17 (10%) strains, the variation in repeated measurements was substantial. These results show that the disk diffusion method may not be a reliable tool for the susceptibility testing of Campylobacter spp. Further studies are needed to assess whether the disk diffusion test could be improved or whether all susceptibilities of campylobacters should be tested using an MIC-based method.

  9. Zinc supplementation in burn patients.

    PubMed

    Caldis-Coutris, Nancy; Gawaziuk, Justin P; Logsetty, Sarvesh

    2012-01-01

    Micronutrient supplementation is a common practice throughout many burn centers across North America; however, uncertainty pertaining to dose, duration, and side effects of such supplements persists. The authors prospectively collected data from 23 hospitalized patients with burn sizes ranging from 10 to 93% TBSA. Each patient received a daily multivitamin and mineral supplement, 50 mg zinc (Zn) daily, and 500 mg vitamin C twice daily. Supplements were administered orally or enterally. Albumin, prealbumin, C-reactive protein, serum Zn, and serum copper were measured weekly during hospital admission until levels were within normal reference range. Our study concluded that 50 mg daily dose of Zn resulted in normal serum levels in 19 of 23 patients at discharge; 50 mg Zn supplementation did not interfere with serum copper levels; and Zn supplements, regardless of administration route, did not result in gastrointestinal side effects.

  10. High internal phase agar hydrogel dispersions in cocoa butter and chocolate as a route towards reducing fat content.

    PubMed

    Skelhon, Thomas S; Olsson, Patrik K A; Morgan, Adam R; Bon, Stefan A F

    2013-09-01

    Reducing the fat content of chocolate formulations is a major challenge for the confectionery industry. We report the suspension of aqueous microgel agar particles of up to 80% v/v within sunflower oil, cocoa butter, and ultimately chocolate. The optimised emulsification process involves a shear-cooling step. We demonstrate the versatility of our method when applied to white, milk, and dark chocolate formulations, whilst preserving the desired polymorph V of the cocoa butter matrix. In addition, we show that this technology can be used as a strategy to disperse alcoholic beverages into chocolate confectionery.

  11. Oxacillin susceptibility testing of Staphylococcus saprophyticus using disk diffusion, agar dilution, broth microdilution, and the Vitek GPS-105 card.

    PubMed

    Ramotar, K; Woods, W; Toye, B

    2001-08-01

    Eighty-three mecA negative isolates of S. saprophyticus had oxacillin zone diameters agar dilution, broth microdilution, or the Vitek GPS-105 card. Greater than 90% of these isolates would be considered resistant using NCCLS M7-A5, M100-S10 criteria. These results suggest that the current NCCLS MIC and zone diameter breakpoints for oxacillin resistance in coagulase-negative Staphylococci are not appropriate for S. saprophyticus as they do not correlate with the presence of the mecA gene.

  12. MICROBIOLOGICAL QUALITY OF FOOD SUPPLEMENTS.

    PubMed

    Ratajczak, Magdalena; Kubicka, Marcelina M; Kamińska, Dorota; Długaszewska, Jolanta

    2015-01-01

    Many specialists note that the food offered today - as a result of very complex technological processing - is devoid of many components that are important for the organism and the shortages have to be supplemented. The simplest for it is to consume diet supplements that provide the missing element in a concentrated form. In accordance with the applicable law, medicinal products include all substances or mixtures of substances that are attributed with properties of preventing or treating diseases with humans or animals. Permits to admit supplements to the market are issued by the Chief Sanitary Inspector and the related authorities; permits for medicines are issued by the Chief Pharmaceutical Inspector and the Office for Registration of Medicinal Products, Medical Devices and Biocidal Products. Therefore, admittance of a supplement to the market is less costly and time consuming_than admittance of a medicine. Supplements and medicines may contain the same component but medicines will have a larger concentration than supplements. Sale of supplements at drug stores and in the form of tablets, capsules, liquids or powders makes consumer often confusing supplements with medicines. Now there are no normative documents specifying limits of microbiological impurities in diet supplements. In Polish legislation, diet supplements are subject to legal acts concerning food. Medicines have to comply with microbiological purity requirements specified in the Polish Pharmacopeia. As evidenced with the completed tests, the proportion of diet supplement samples with microbiological impurities is 6.5%. Sales of diet supplements have been growing each year, they are consumed by healthy people but also people with immunology deficiencies and by children and therefore consumers must be certain that they buy safe products.

  13. Bodybuilding supplementation and tooth decay.

    PubMed

    Ali, M S; Batley, H; Ahmed, F

    2015-07-10

    Supplementation is a key component in bodybuilding and is increasingly being used by amateur weight lifters and enthusiasts to build their ideal bodies. Bodybuilding supplements are advertised to provide nutrients needed to help optimise muscle building but they can contain high amounts of sugar. Supplement users are consuming these products, while not being aware of their high sugar content, putting them at a higher risk of developing dental caries. It is important for dental professionals to recognise the increased risk for supplement users and to raise awareness, provide appropriate preventative advice and be knowledgeable of alternative products to help bodybuilders reach their goals, without increasing the risk of dental caries.

  14. Nutritional Supplementation and Meal Timing

    NASA Astrophysics Data System (ADS)

    Farris, Jim

    For the competitive athlete and the serious recreational athlete, nutritional supplementation can have a positive effect on training and on performance. There are many fad supplements on the market, and many that have come and gone. However, two nutrients have withstood the test of time and many tests in research laboratories around the world, and they continue to have positive training- and performance-enhancing effects. Carbohydrates are commonly supplemented to improve energy availability and to replace valuable muscle and liver glycogen stores. Protein supplementation usually is associated with building muscle tissue.

  15. Dietary supplements for aquatic sports.

    PubMed

    Derave, Wim; Tipton, Kevin D

    2014-08-01

    Many athletes use dietary supplements, with use more prevalent among those competing at the highest level. Supplements are often self-prescribed, and their use is likely to be based on an inadequate understanding of the issues at stake. Supplementation with essential micronutrients may be useful when a diagnosed deficiency cannot be promptly and effectively corrected with food-based dietary solutions. When used in high doses, some supplements may do more harm than good: Iron supplementation, for example, is potentially harmful. There is good evidence from laboratory studies and some evidence from field studies to support health or performance benefits from appropriate use of a few supplements. The available evidence from studies of aquatic sports is small and is often contradictory. Evidence from elite performers is almost entirely absent, but some athletes may benefit from informed use of creatine, caffeine, and buffering agents. Poor quality assurance in some parts of the dietary supplements industry raises concerns about the safety of some products. Some do not contain the active ingredients listed on the label, and some contain toxic substances, including prescription drugs, that can cause health problems. Some supplements contain compounds that will cause an athlete to fail a doping test. Supplement quality assurance programs can reduce, but not entirely eliminate, this risk.

  16. Growth and maintenance of an embryogenic cell culture of daylily (Hemerocallis) on hormone-free medium

    NASA Technical Reports Server (NTRS)

    Smith, D. L.; Krikorian, A. D.

    1991-01-01

    Callus cultures of the diploid daylily (Hemerocallis) clone Autumn Blaze' were initiated and maintained in hormone-containing nutrient medium. At various times (from 6 weeks to 1 year) after being initiated, hormone-derived cultures were evaluated for their ability to be maintained and to multiply on hormone-free medium at low pH (between pH 4 and 4.5). Cultures had to be exposed to hormone-containing medium for at least 12 weeks before they could be maintained on hormone-free medium at low pH. The transition to maintainability on low pH hormone-free medium included the production of many aberrant embryonal forms ( neomorphs'). However, all hormone-derived cultures tested consisted entirely of preglobular stage proembryos (PGSPs) after 12-24 weeks on low pH hormone-free medium. PGSP cultures have been maintained and multiplied as such for over 1 year on low pH hormone-free medium. PGSPs continue their development into various somatic embryo stages when cultured on hormone-free medium buffered at pH 5.8. The production of well-formed somatic embryos was greatly enhanced when PGSPs were plated on activated charcoal impregnated filter papers that were placed on top of the agar surface. The gross morphology and histology of the PGSPs and stages of somatic embryo development are presented. The work shows that the ability of hormone-free medium at low pH to permit PGSP multiplication without development into later stages of embryo development is not restricted to carrot.

  17. Production of Agaricus bisporus on substrates pre-colonized by Scytalidium thermophilum and supplemented at casing with protein-rich supplements.

    PubMed

    Coello-Castillo, M M; Sánchez, J E; Royse, D J

    2009-10-01

    The objective of this study was to evaluate performance of Agaricus bisporus (Ab) on substrates pre-colonized by Scytalidiumthermophilum (St), a thermophilic fungus known to enhance yields of Ab and increase selectivity of the substrate. The radial extension rate (RER) of the mycelium of three strains of St and their influence on the growth of a brown strain of Ab were evaluated. We also determined the time required for colonization of pangola grass by St in a compost pile and the influence of three protein-rich supplements on yield of Ab on pangola grass (Digitaria decumbens) colonized by St. RER of St ranged from 10.1mm/d on grass to 18.9 mm/d on potato dextrose yeast extract agar, with significant differences among substrates and among strains. Ab grew faster on substrate colonized for 1, 2, or 3 days by St (RER of 3.31, 3.29, 3.23 mm/d, respectively) compared to non-colonized substrate (1.85 mm/d). Ab was cultivated on substrate samples selected daily from the St-inoculated pile, with biological efficiencies (BE) ranging from 4% (day 0) to 73.9% (day 2). Protein-rich supplements (soybean, black beans and cowpeas) added at casing significantly stimulated mushroom yield on St-colonized substrate compared to the non-supplemented control. BE varied from 26.1% on substrate non-supplemented to 73.1% on compost supplemented with ground soybean. There were no significant differences in mushroom yield observed among supplements evaluated.

  18. 32 CFR 651.24 - Supplemental EAs and supplemental EISs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 4 2012-07-01 2011-07-01 true Supplemental EAs and supplemental EISs. 651.24 Section 651.24 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) ENVIRONMENTAL QUALITY ENVIRONMENTAL ANALYSIS OF ARMY ACTIONS (AR 200-2) Records and Documents §...

  19. 32 CFR 651.24 - Supplemental EAs and supplemental EISs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 4 2014-07-01 2013-07-01 true Supplemental EAs and supplemental EISs. 651.24 Section 651.24 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) ENVIRONMENTAL QUALITY ENVIRONMENTAL ANALYSIS OF ARMY ACTIONS (AR 200-2) Records and Documents §...

  20. 32 CFR 651.24 - Supplemental EAs and supplemental EISs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Supplemental EAs and supplemental EISs. 651.24 Section 651.24 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) ENVIRONMENTAL QUALITY ENVIRONMENTAL ANALYSIS OF ARMY ACTIONS (AR 200-2) Records and Documents §...

  1. 32 CFR 651.24 - Supplemental EAs and supplemental EISs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 4 2011-07-01 2011-07-01 false Supplemental EAs and supplemental EISs. 651.24 Section 651.24 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) ENVIRONMENTAL QUALITY ENVIRONMENTAL ANALYSIS OF ARMY ACTIONS (AR 200-2) Records and Documents §...

  2. 32 CFR 651.24 - Supplemental EAs and supplemental EISs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 4 2013-07-01 2013-07-01 false Supplemental EAs and supplemental EISs. 651.24 Section 651.24 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) ENVIRONMENTAL QUALITY ENVIRONMENTAL ANALYSIS OF ARMY ACTIONS (AR 200-2) Records and Documents §...

  3. Effects of medium and inoculum variations on screening for high-level aminoglycoside resistance in Enterococcus faecalis.

    PubMed Central

    Sahm, D F; Torres, C

    1988-01-01

    Enterococcus faecalis isolates that are refractory to aminoglycoside-penicillin synergy can be detected by their ability to grow in the presence of high concentrations of aminoglycoside (2,000 micrograms/ml). In past studies investigators have used a variety of media and inoculum sizes to perform high-level aminoglycoside resistance screens, but little is known about how these variations affect test accuracy. We screened 63 E. faecalis strains on different media by using various inoculum sizes and correlated the results with synergy test results obtained by time-kill studies. Screens were done with dextrose-phosphate agar, brain heart infusion agar, Trypticase soy agar with 5% sheep blood, Mueller-Hinton agar with 5% sheep blood, dextrose-phosphate broth, and Mueller-Hinton broth. Agar screens were inoculated with 10(2), 10(4), and 10(6) CFU; and broth screens contained a final inoculum of 10(5) CFU/ml. The E. faecalis isolates were tested for high-level resistance to streptomycin, kanamycin, amikacin, gentamicin, and tobramycin. Of the 63 isolates tested, 21 did not show high-level resistance to any of the aminoglycosides tested, and 42 demonstrated high-level resistance to one or more drugs. The sensitivity of most screens was greater than or equal to 90%. Regardless of the inoculum size or medium used, false-resistance results were seldom encountered. Screen specificity, which was used as the indicator of false susceptibility, was markedly influenced by both the inoculum size and the drug being tested. Specificity was low whenever a 10(2)-CFU inoculum was used, when amikacin was tested with any inoculum, and when tobramycin was tested in broth media. Data for kanamycin could be used to predict amikacin-penicillin synergy, and the highly accurate gentamicin screen obviated the need for the testing of tobramycin. We recommend a 10(6) -CFU inoculum for agar screens and a 10(5) -CFU/ml inoculum for broth screens. The type of medium used did not substantially

  4. Algivirga pacifica gen. nov., sp. nov., a novel agar-degrading marine bacterium of the family Flammeovirgaceae isolated from Micronesia.

    PubMed

    Kim, Jennifer Jooyoun; Kim, Ji Hyung; Kwon, Young-Kyung; Kwon, Kae Kyoung; Yang, Sung-Hyun; Jang, Jiyi; Heo, Soo-Jin; Park, Heung-Sik; Jung, Won-Kyo; Lee, Youngdeuk; Kang, Do-Hyung; Oh, Chulhong

    2013-12-01

    An aerobic, Gram-negative, coccoid to short rod-shaped and non-flagellated marine bacterial strain S354(T) was isolated from seawater of Micronesia. The strain was capable to degrade agar-forming slight depression into agar plate. Growth occurred at a temperature range of 12-44 °C, a pH range of 5-9, and a salinity range of 1-7 % (w/v) NaCl. Phylogenetic analyses based on 16S rRNA gene sequences suggested that S354(T) belongs to the family Flammeovirgaceae. The novel strain was most closely related to Limibacter armeniacum YM 11-185(T) with similarity of 92.5 %. The DNA G+C content was 43.8 mol%. The major fatty acids (>10 %) were iso-C15:0 and C16:1 ω5c. The predominant isoprenoid quinone was determined to be MK-7. Polar lipid profile of S354(T) consisted of phosphatidylethanolamine, unknown polar lipid, and unknown glycolipids. Based on the phenotypic, phylogenetic, biochemical, and physiological tests conducted in this study, S354(T) is proposed to represent a type strain of a novel genus and species. The 16S rRNA gene sequence of S354(T) is registered in GenBank under the accession number JQ639084. The type of strain Algivirga pacifica gen. nov., sp. nov. is S354(T) (=KCCM 90107(T)=JCM 18326(T)).

  5. Acrylamide synthesis using agar entrapped cells of Rhodococcus rhodochrous PA-34 in a partitioned fed batch reactor.

    PubMed

    Raj, Jog; Sharma, Nitya Nand; Prasad, Shreenath; Bhalla, Tek Chand

    2008-01-01

    The nitrile hydratase (Nhase) induced cells of Rhodococcus rhodochrous PA-34 catalyzed the conversion of acrylonitrile to acrylamide. The cells of R. rhodochrous PA-34 immobilized in 2% (w/v) agar (1.76 mg dcw/ml agar matrix) exhibited maximum Nhase activity (8.25 U/mg dcw) for conversion of acrylonitrile to acrylamide at 10 degrees C in the reaction mixture containing 0.1 M potassium phosphate buffer (pH 7.5), 8% (w/v) acrylonitrile and immobilized cells equivalent to 1.12 mg dcw (dry cell weight) per ml. In a partitioned fed batch reaction at 10 degrees C, using 1.12 g dcw immobilized cells in a final volume of 1 l, a total of 372 g of acrylonitrile was completely hydrated to acrylamide (498 g) in 24 h. From the above reaction mixture 87% acrylamide (432 g) was recovered through crystallization at 4 degrees C. By recycling the immobilized biocatalyst (six times), a total of 2,115 g acrylamide was produced.

  6. Internal structures of agar-gelatin co-hydrogels by light scattering, small-angle neutron scattering and rheology.

    PubMed

    Santinath Singh, S; Aswal, V K; Bohidar, H B

    2011-06-01

    Internal structures of agar-gelatin co-hydrogels were investigated as a function of their volumetric mixing ratio, [Formula: see text] , 1.0 and 2.0 using dynamic light scattering (DLS), small-angle neutron scattering (SANS) and rheology. The degree of non-ergodicity ( X = 0.2 ± 0.02) , which was extracted as a heterodyne contribution from the measured dynamic structure factor data remained less than that of homogeneous solutions where ergodicity is expected (X = 10. The static structure factor, I(q) , results obtained from SANS were interpreted in the Guinier regime (low-q , which implied the existence of ≈ 250 nm long rod-like structures (double-helix bundles), and the power law (intermediate-q regions) yielded I (q) ~ q(−α) with α = 2.3 , 1.8 and 1.6 for r = 0.5 , 1.0 and 2.0. This is indicative of the presence of Gaussian chains at low r , while at r = 2 there was a propensity of rod-shaped structures. The gel strength and transition temperatures measured from frequency sweep and temperature ramp studies were suggestive of the presence of a stronger association between the two biopolymer networks at higher r . The results indicate that the internal structures of agar-gelatin co-hydrogels were highly dependent on the volumetric mixing ratio.

  7. Josamycin: interpretation of inhibition zones with the Bauer-Kirby agar disk diffusion test as compared with erythromycin.

    PubMed

    Karthein, J; Spohr, M; Traub, W H

    1986-01-01

    A total of 432 clinical isolates of Staphylococcus aureus (128), coagulase-negative staphylococci (123), group A and B beta-hemolytic streptococci (61), group D streptococci (30), Streptococcus penumoniae (29), Haemophilus influenzae (19), Haemophilus parainfluenzae (12), and Legionella pneumophila (30) were examined with the agar dilution and Bauer-Kirby agar disk diffusion tests for susceptibility to josamycin as compared with erythromycin. On a weight-for-weight basis, erythromycin was more active than josamycin against all bacterial species, including L. pneumophila. Josamycin inhibited 18 of 23 S. aureus and 11 of 16 coagulase-negative staphylococcal strains resistant to erythromycin. Utilizing minimal inhibitory concentrations (MIC) breakpoints of less than or equal to 2 micrograms/ml (sensitive), 4 microgram/ml (intermediate) and of greater than or equal to 8 micrograms/ml (resistant), and inhibition zone criteria of greater than or equal to 18 mm diameter (sensitive), 14-17 mm (intermediate), and less than or equal to 13 mm (resistant), and excluding L. pneumophila, there was good correlation between erythromycin MIC and corresponding disk diffusion data for staphylococci and streptococci, but not for Haemophilus species. In comparison, josamycin yielded a significant number of minor discrepant data for group D streptococci and Haemophilus species. It is suggested that erythromycin and josamycin should not be tested against Haemophilus species, and that josamycin should be excluded from test batteries against enterococci. Erythromycin-resistant staphylococci require separate testing with josamycin.

  8. Agar-Silica-Gel Heating Phantom May Be Suitable for Long-Term Quality Assurance of MRgHIFU

    NASA Astrophysics Data System (ADS)

    Partanen, Ari

    2009-04-01

    In MRgHIFU, the purpose of frequent quality assurance is to detect changes in system performance to prevent adverse effects during treatments. Due to high ultrasound intensities in MRgHIFU, it is essential to assure that the procedure is safe and efficacious and that image-based guidance of the treatment is reliable. We aimed to develop a guideline for MRgHIFU QA by acquiring MR temperature maps during ultrasonic heating of an agar-silica-gel phantom over a four month-period using three separate MRgHIFU uterine leiomyoma treatment systems. From this data, the stability of the maximum temperature elevation, the targeting accuracy, and the dimensions of the heated volume were analyzed. Additionally, we studied the sensitivity of these parameters to reveal hypothetical decrease in HIFU performance. After calibration, the mean targeting offsets of the heated volume were observed to be less than 2 mm in the three orthogonal directions. The measured maximum temperature elevation and the length and the width of the heated volume remained consistent throughout the four-month period. Furthermore, it was found that the parameters under investigation were sensitive to reveal the decreased HIFU performance. We conclude that an agar-silica -based phantom is suitable for targeting accuracy and heating properties QA of MRgHIFU system even in long-term use. Moreover, this simple QA method may be used to reveal small changes in HIFU performance assuring consistent functionality and safety of the MRgHIFU system.

  9. CHROMagar Candida as the Sole Primary Medium for Isolation of Yeasts and as a Source Medium for the Rapid-Assimilation-of-Trehalose Test

    PubMed Central

    Murray, Melissa P.; Zinchuk, Riva; Larone, Davise H.

    2005-01-01

    The chromogenic medium BBL CHROMagar Candida (CAC) was evaluated as a sole primary medium for the isolation of yeasts from clinical specimens in which yeasts are the primary concern. Additionally, the reliability of the rapid-assimilation-of-trehalose (RAT) test in yielding correct results with isolates taken from CAC was assessed. A total of 270 throat, urine, and genital (TUG) specimens were streaked onto CAC, Sabouraud dextrose agar (SDA), inhibitory mold agar (IMA), and Mycosel (MYC). A total of 69 blood culture broths that were smear positive for yeast were streaked onto CAC and SDA. A 1-h RAT test (NCCLS M35-A) was performed simultaneously on isolates from CAC and SDA. A total of 112 TUG specimens yielded yeast colonies (CAC, 111 colonies; IMA, 105; SDA, 103; MYC, 91). The 69 blood culture yeasts grew on both CAC and SDA. Mixed cultures of yeasts were detected on 11 CAC plates but were unrecognized on other media. Colonies suspected of being C. glabrata on 32 CAC plates were all RAT test positive and confirmed to be C. glabrata; of 59 colonies with various characteristics of color and morphology on CAC, none were RAT positive, and all were conventionally identified as yeasts other than C. glabrata (sensitivity and specificity, 100%). The same isolates from SDA tested for RAT produced six false negatives and no false positives (sensitivity, 81%; specificity, 100%). The results show that CAC can be used as the sole primary medium for recovery of yeasts from clinical specimens. Additionally, isolates grown on CAC yield excellent results with the RAT test utilized in this study. PMID:15750085

  10. CHROMagar Candida as the sole primary medium for isolation of yeasts and as a source medium for the rapid-assimilation-of-trehalose test.

    PubMed

    Murray, Melissa P; Zinchuk, Riva; Larone, Davise H

    2005-03-01

    The chromogenic medium BBL CHROMagar Candida (CAC) was evaluated as a sole primary medium for the isolation of yeasts from clinical specimens in which yeasts are the primary concern. Additionally, the reliability of the rapid-assimilation-of-trehalose (RAT) test in yielding correct results with isolates taken from CAC was assessed. A total of 270 throat, urine, and genital (TUG) specimens were streaked onto CAC, Sabouraud dextrose agar (SDA), inhibitory mold agar (IMA), and Mycosel (MYC). A total of 69 blood culture broths that were smear positive for yeast were streaked onto CAC and SDA. A 1-h RAT test (NCCLS M35-A) was performed simultaneously on isolates from CAC and SDA. A total of 112 TUG specimens yielded yeast colonies (CAC, 111 colonies; IMA, 105; SDA, 103; MYC, 91). The 69 blood culture yeasts grew on both CAC and SDA. Mixed cultures of yeasts were detected on 11 CAC plates but were unrecognized on other media. Colonies suspected of being C. glabrata on 32 CAC plates were all RAT test positive and confirmed to be C. glabrata; of 59 colonies with various characteristics of color and morphology on CAC, none were RAT positive, and all were conventionally identified as yeasts other than C. glabrata (sensitivity and specificity, 100%). The same isolates from SDA tested for RAT produced six false negatives and no false positives (sensitivity, 81%; specificity, 100%). The results show that CAC can be used as the sole primary medium for recovery of yeasts from clinical specimens. Additionally, isolates grown on CAC yield excellent results with the RAT test utilized in this study.

  11. Performance of Hitchens-Pike-Todd-Hewitt Medium for Group B Streptococcus Screening in Pregnant Women

    PubMed Central

    de Melo, Simone Cristina Castanho Sabaini; Gavena, Angela Andréia França; Silva, Flávia Teixeira Ribeiro; Moreira, Ricardo Castanho; de Lima Scodro, Regiane Bertin; Cardoso, Rosilene Fressatti; Siqueira, Vera Lúcia Dias; de Pádua, Rúbia Andreia Faleiros; Carvalho, Maria Dalva de Barros; Pelloso, Sandra Marisa

    2015-01-01

    Group B streptococcus (GBS), which commonly colonizes the female genital tract and rectum, can cause infections in newborns with varying severity, possibly leading to death. The aim of the present study was to evaluate Hitchens-Pike-Todd-Hewitt (HPTH) medium performance for GBS screening in pregnant women. A descriptive analytical cross-sectional study was performed with 556 pregnant women, of which 496 were at 35-37 weeks of gestation and 60 were at ≥ 38 weeks of gestation. The study was conducted from September 2011 to March 2014 in northern Paraná, Brazil. Vaginal and anorectal clinical specimens from each pregnant woman were plated on sheep blood agar (SBA) and seeded on HPTH medium and Todd-Hewitt enrichment broth. Of the 496 pregnant women at 35-37 weeks of gestation, 141 (28.4%) were positive for GBS, based on the combination of the three culture media and clinical specimens. The GBS colonization rates that were detected by each medium were 22.2% for HPTH medium, 21.2% for SBA, and 13.1% for Todd-Hewitt enrichment broth. Of the 60 pregnant women at ≥ 38 weeks of gestation, seven (11.7%) were positive for GBS. These results demonstrate that HPTH medium and SBA were more sensitive than Todd-Hewitt enrichment broth for GBS screening in pregnant women and good GBS recovery in culture, indicating that the two media should be used together for vaginal and anorectal specimens. PMID:25881083

  12. Double sugar-tyrosine medium improves O-1 phage Salmonella screening.

    PubMed Central

    Thaller, M C; Dainelli, B; Berlutti, F; Schippa, S; Fontana, C; Pezzi, R

    1992-01-01

    A modification of the procedure for O-1 phage Salmonella screening is presented. The novel method is based on the use of two media, i.e., a new medium (double sugar-tyrosine [DST]), which permits the combination of adonitol and sucrose fermentation and tyrosine clearing tests, and the previously described o-nitrophenyl-beta-D-galactopyranoside urease indole medium. In comparative trials, the new procedure and the conventional one were used to screen for Salmonella isolates from 553 lactose-negative strains of members of the family Enterobacteriaceae. The O-1 phage test, performed on DST medium, recognized the same number of phage-susceptible Salmonella strains as did the standardized method; however, it permitted the correct identification of a greater number of phage-resistant strains for discard (95.6 versus 85.3%). In particular, DST medium presented a higher efficacy than triple sugar iron agar (which is the corresponding medium in the reference procedure) in correctly identifying phage-negative cultures for discard (69.1 versus 28.5%). PMID:1537932

  13. Nutritional Supplements for Endurance Athletes

    NASA Astrophysics Data System (ADS)

    Rasmussen, Christopher J.

    Athletes engaged in heavy endurance training often seek additional nutritional strategies to help maximize performance. Specific nutritional supplements exist to combat certain factors that limit performance beginning with a sound everyday diet. Research has further demonstrated that safe, effective, legal supplements are in fact available for today's endurance athletes. Several of these supplements are marketed not only to aid performance but also to combat the immunosuppressive effects of intense endurance training. It is imperative for each athlete to research the legality of certain supplements for their specific sport or event. Once the legality has been established, it is often up to each individual athlete to decipher the ethics involved with ingesting nutritional supplements with the sole intent of improving performance.

  14. Drugs, Herbs and Supplements: MedlinePlus

    MedlinePlus

    ... this page: https://medlineplus.gov/druginformation.html Drugs, Herbs and Supplements To use the sharing features on ... approved labels included in drug packages, see DailyMed . Herbs and Supplements Browse dietary supplements and herbal remedies ...

  15. Improved detection of vanB2-containing enterococcus faecium with vancomycin susceptibility by Etest using oxgall supplementation.

    PubMed

    Grabsch, E A; Chua, K; Xie, S; Byrne, J; Ballard, S A; Ward, P B; Grayson, M L

    2008-06-01

    We have isolated a number of vanB-containing Enterococcus faecium isolates on bile esculin screening agar containing 6 mg/liter vancomycin, which on subsequent susceptibility testing using Etest have repeatedly demonstrated vancomycin MICs of supplemented media to improve phenotypic detection of these isolates. Etest detection of LM-VRE improved when Mueller-Hinton agar (MHA) and brain heart infusion agar (BHIA) were supplemented with 10 g/liter oxgall (MHA-Oxg and BHIA-Oxg, respectively). We assessed the sensitivity and specificity of these media to detect vancomycin resistance using vancomycin-resistant vanB-containing E. faecium (n = 11), vancomycin-susceptible (van negative) E. faecium (n = 11), vancomycin-susceptible (van negative) E. faecalis (n = 11), and our LM-VRE (n = 23) isolates. After 48 h of incubation, both MHA-Oxg and BHIA-Oxg were 100% (34/34) sensitive and 100% (22/22) specific in the identification of vancomycin resistance. These findings suggest that supplementation of MHA or BHIA with 10 g/liter oxgall should be considered in laboratories where VRE detection protocols rely primarily on strain phenotype rather than early vanB gene detection by PCR.

  16. Comparison of dry medium culture plates for mesophilic aerobic bacteria in milk, ice cream, ham, and codfish fillet products.

    PubMed

    Park, Junghyun; Kim, Myunghee

    2013-12-01

    This study was performed to compare the performance of Sanita-Kun dry medium culture plate with those of traditional culture medium and Petrifilm dry medium culture plate for the enumeration of the mesophilic aerobic bacteria in milk, ice cream, ham, and codfish fillet. Mesophilic aerobic bacteria were comparatively evaluated in milk, ice cream, ham, and codfish fillet using Sanita-Kun aerobic count (SAC), Petrifilm aerobic count (PAC), and traditional plate count agar (PCA) media. According to the results, all methods showed high correlations of 0.989~1.000 and no significant differences were observed for enumerating the mesophilic aerobic bacteria in the tested food products. SAC method was easier to perform and count colonies efficiently as compared to the PCA and PAC methods. Therefore, we concluded that the SAC method offers an acceptable alternative to the PCA and PAC methods for counting the mesophilic aerobic bacteria in milk, ice cream, ham, and codfish fillet products.

  17. Media for the aerobic growth of campylobacter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of agar and sodium bicarbonate (NaHCO3) concentration on aerobic growth of Campylobacter in a fumarate-pyruvate medium was examined. The broth medium was supplemented with 0.0 to 0.2% agar and inoculated with 106 CFU/ml of Campylobacter coli 33559, Campylobacter fetus 27349, Campylobacter...

  18. Hemolytic Activities of the Candida Species in Liquid Medium

    PubMed Central

    Malcok, Hilal Kuzucu; Aktas, Esin; Ayyildiz, Ahmet; Yigit, Nimet; Yazgi, Halil

    2009-01-01

    Objective The aim of this study was to evaluate the in vitro hemolytic activities of 107 Candida strains isolated from different clinical samples in liquid medium, and to examine the impact of glucose on this activity. Materials and Methods A total of 107 Candida isolates representing seven species (C. albicans, n=28; C. glabrata, n=23; C. tropicalis, n=17; C. parapsilosis, n=16; C. kefyr, n=14; C. krusei, n=5; C. guilliermondii, n=4) were included in the study. The hemolytic activities of the strains were tested on two different Sabouraud dextrose liquid media (SDB) containing 7% defibrinated human blood, one of which is supplemented with 3% glucose and the other without glucose. Cultures were evaluated at the end of a 48-hour incubation. The hemolysis in the media was detected spectrophotometrically by measuring the amount of released hemoglobin and compared with a standard hemolysate which was prepared prior to testing. The degree of hemolysis (percentage value) by an individual strain was calculated according to the following formula below: (Absorbance of supernatant media at 540 nm / Absorbance of standard hemolysate at 540 nm X 100). Results In the liquid medium without glucose, strains generally produced hemolysis at low levels. The degree of hemolysis produced by all species increased noticeably in the liquid medium with glucose. Strains of C. albicans and C.kefyr had demonstrated significant hemolytic activity, whereas others had lower activity. C. parapsilosis exerted very little hemolytic activity in the medium with glucose and showed no activity in the medium without glucose. Conclusion The hemolytic activities of most Candida species was found to be higher in the human blood-enriched SDB medium containing 3% additive glucose than in the one free from additives. This result indicates that increased blood glucose concentration may contribute to increased hemolytic activity in Candida species, and it suggests a parallel with possible pathogenesis of

  19. Application of in vitro soft agar techniques for growth of tumor cells to the study of colon cancer.

    PubMed

    Buick, R N; Fry, S E; Salmon, S E

    1980-03-15

    An in vitro assay to measure the clonogenic or colony-forming capability of cancer cells present in biopsy samples has recently been applied to study the biology and drug-sensitivity of a variety of human neoplasms. This approach appears to be suitable for study of the tumor stem or progenitor cells present in malignant effusions from patients with colonic carcinoma. In our preliminary studies, morphology of the tumor colonies by inverted microscopy and with Papanicolaou staining of dried agar plating layers as well as immunofluorescent localization with a specific antiserum to human carcinoembrionic antigen have been used as markers of the neoplastic origin of colon tumor colony-forming cells. Successful application of this assay to colonic solid tumors will require improvement in techniques for disaggregation of viable clonogenic cells. We anticipate that short term clonal assays will have increasing use for clinical and biological studies of human colon cancer.

  20. The agar diffusion scratch assay - A novel method to assess the bioactive and cytotoxic potential of new materials and compounds

    PubMed Central

    Pusnik, Mascha; Imeri, Minire; Deppierraz, Grégoire; Bruinink, Arie; Zinn, Manfred

    2016-01-01

    A profound in vitro evaluation not only of the cytotoxic but also of bioactive potential of a given compound or material is crucial for predicting potential effects in the in vivo situation. However, most of the current methods have weaknesses in either the quantitative or qualitative assessment of cytotoxicity and/or bioactivity of the test compound. Here we describe a novel assay combining the ISO 10993-5 agar diffusion test and the scratch also termed wound healing assay. In contrast to these original tests this assay is able to detect and distinguish between cytotoxic, cell migration modifying and cytotoxic plus cell migration modifying compounds, and this at higher sensitivity and in a quantitative way. PMID:26861591