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Role of iron and aluminum coagulant metal residuals and lead release from drinking water pipe materials 2015 a Department of Civil & Resource Engineering , Dalhousie University , Halifax , Nova Scotia , Canada.
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Journal Article
Periodical, Full
Journal of environmental science and health.Part A, Toxic/hazardous substances & environmental engineering
Periodical, Abbrev.
J.Environ.Sci.Health.A.Tox.Hazard.Subst.Environ.Eng.
Pub Date Free Form
Volume
50
Issue
4
Start Page
414
Other Pages
423
Notes
LR: 20160526; JID: 9812551; 0 (Chlorides); 0 (Drinking Water); 0 (Sulfates); 0 (Water Pollutants, Chemical); 2P299V784P (Lead); CPD4NFA903 (Aluminum); E1UOL152H7 (Iron); OTO: NOTNLM; ppublish
Place of Publication
England
ISSN/ISBN
1532-4117; 1093-4529
Accession Number
PMID: 25723068
Language
eng
SubFile
Journal Article; Research Support, Non-U.S. Gov't; IM
DOI
10.1080/10934529.2015.987550 [doi]
Output Language
Unknown(0)
PMID
25723068
Abstract
Bench-scale experiments investigated the role of iron and aluminum residuals in lead release in a low alkalinity and high (> 0.5) chloride-to-sulfate mass ratio (CSMR) in water. Lead leaching was examined for two lead-bearing plumbing materials, including harvested lead pipe and new lead: tin solder, after exposure to water with simulated aluminum sulfate, polyaluminum chloride and ferric sulfate coagulation treatments with 1-25-muM levels of iron or aluminum residuals in the water. The release of lead from systems with harvested lead pipe was highly correlated with levels of residual aluminum or iron present in samples (R(2) = 0.66-0.88), consistent with sorption of lead onto the aluminum and iron hydroxides during stagnation. The results indicate that aluminum and iron coagulant residuals, at levels complying with recommended guidelines, can sometimes play a significant role in lead mobilization from premise plumbing.
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Database
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Data Source
Authors
Knowles,A.D., Nguyen,C.K., Edwards,M.A., Stoddart,A., McIlwain,B., Gagnon,G.A.
Original/Translated Title
URL
Date of Electronic
PMCID
Editors
Role of members of university students' unions in tobacco prevention 2007
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Print(0)
Ref Type
Journal Article
Periodical, Full
J Prev Med Hyg
Periodical, Abbrev.
Pub Date Free Form
Volume
48
Issue
4
Start Page
136
Other Pages
40
Notes
ID: 18557308
Place of Publication
ISSN/ISBN
Accession Number
Language
en
SubFile
DOI
Output Language
Unknown(0)
PMID
Abstract
INTRODUCTION: In Egypt, each faculty has it own students' union, which represents the students and collaborates in organizing all educational, sporting and social activities. The objectives of the current study were to evaluate the knowledge of members of students' unions about cigarette and Shisha smoking together with assessing their attitudes towards smoking in public places in general and in the university. METHODOLOGY: A random sample of members of Ain Shams University Students' Unions was subjected to an interview questionnaire. All participants were individually interviewed face-to-face by a trained interviewer from March 1, 2005 to April 30, 2005. RESULTS: Our study showed that 34 (31.5%) students were smokers. The mean knowledge score percentage was 79.4 +/- 20.7. Regarding knowledge about Shisha smoking hazards, the majority of the students (84.3%) knew that Shisha smoking is hazardous. The mean attitude score percentage was 56.8 +/- 22.2. Smokers had less mean knowledge as regard smoking hazards compared to non-smokers (p < 0.01). Also, smokers had a lower mean attitude compared to non-smokers (p < 0.001). More than one-third (38.9%) of the interviewed students didn't know if the students' union has a policy for prevention of smoking or not. CONCLUSION: Our findings point that although our students had a moderately high mean knowledge score yet this didn't increase their attitude about the smoking problem in the university and in the community. This supports the notion that, in addition to knowledge about smoking hazards, efforts are needed to change beliefs that allow this offensive habit to continue.
Descriptors
Health Knowledge, Attitudes, Practice, Health Promotion, Smoking/prevention & control, Social Marketing, Students, Universities, Adolescent, Adult, Age Factors, Egypt, Humans, Male, Organizational Policy, Spain, Questionnaires
Links
http://pesquisa.bvsalud.org/ghl/resource/en/mdl-18557308
Book Title
Database
MEDLINE; http://www.globalhealthlibrary.net/
Publisher
Data Source
Authors
Allam,M. F., Abd Elaziz,K.M.
Original/Translated Title
URL
Date of Electronic
PMCID
Editors
Role of snus in initiation and cessation of tobacco smoking in Sweden 2006 Institute for Tobacco Studies, Stockholm, Sweden. tobstud@algonet.se
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Print(0)
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Journal Article
Periodical, Full
Tobacco control
Periodical, Abbrev.
Tob.Control
Pub Date Free Form
Jun
Volume
15
Issue
3
Start Page
210
Other Pages
214
Notes
LR: 20140909; JID: 9209612; OID: NLM: PMC2564662; ppublish
Place of Publication
England
ISSN/ISBN
1468-3318; 0964-4563
Accession Number
PMID: 16728752
Language
eng
SubFile
Journal Article; Research Support, Non-U.S. Gov't; IM
DOI
15/3/210 [pii]
Output Language
Unknown(0)
PMID
16728752
Abstract
OBJECTIVE: To examine patterns of smoking and snus use and identify individual pathways of Swedish tobacco users in order to clarify whether snus use is associated with increased or decreased smoking. METHODS: Retrospective analysis of data from a cross-sectional survey completed by 6752 adult Swedes in 2001-2 focusing on identifying tobacco use history by survey items on current and prior tobacco use and smoking initiation and cessation procedures. RESULTS: 15% of the men and 19% of the women completing the survey were daily smokers. 21% of the men and 2% of the women were daily snus users. Almost all (91%) male daily smoking began before the age of 23 years, whereas initiation of daily snus use continued throughout the age range (33% of initiation after age 22). 20% of male primary snus users started daily smoking compared to 47% of non-primary snus users. Thus, the odds of initiating daily smoking were significantly lower for men who had started using snus than for those who had not (odds ratio (OR) 0.28, 95% confidence interval (CI) 0.22 to 0.36). Among male primary smokers, 28% started secondary daily snus use and 73% did not. 88% of those secondary snus users had ceased daily smoking completely by the time of the survey as compared with 56% of those primary daily smokers who never became daily snus users (OR 5.7, 95% CI 4.9 to 8.1). Among men who made attempts to quit smoking, snus was the most commonly used cessation aid, being used by 24% on their latest quit attempt. Of those men who had used one single cessation aid 58% had used snus, as compared with 38% for all nicotine replacement therapy products together. Among men who used snus as a single aid, 66% succeeded in quitting completely, as compared with 47% of those using nicotine gum (OR 2.2, 95% CI 1.3 to 3.7) or 32% for those using the nicotine patch (OR 4.2, 95% CI 2.1 to 8.6). Women using snus as an aid were also significantly more likely to quit smoking successfully than those using nicotine patches or gum. CONCLUSION: Use of snus in Sweden is associated with a reduced risk of becoming a daily smoker and an increased likelihood of stopping smoking.
Descriptors
Adolescent, Adult, Age Distribution, Aged, Female, Humans, Male, Middle Aged, Prevalence, Retrospective Studies, Sex Distribution, Smoking/epidemiology/prevention & control, Smoking Cessation/methods/statistics & numerical data, Sweden/epidemiology, Tobacco Use Disorder/epidemiology/rehabilitation, Tobacco, Smokeless
Links
Book Title
Database
Publisher
Data Source
Authors
Ramstrom,L. M., Foulds,J.
Original/Translated Title
URL
Date of Electronic
PMCID
PMC2564662
Editors
Role of some environmental factors on the breeding activity of Anopheles arabiensis in New Halfa town, eastern Sudan 2008 Entomology Unit, Faculty of Agriculture and Natural Resources, University of Kassala, New Halfa, Sudan. yosifhimeidan@hotmail.com
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Print(0)
Ref Type
Journal Article
Periodical, Full
Eastern Mediterranean health journal = La revue de sante de la Mediterranee orientale = al-Majallah al-sihhiyah li-sharq al-mutawassit
Periodical, Abbrev.
East.Mediterr.Health J.
Pub Date Free Form
Mar-Apr
Volume
14
Issue
2
Start Page
252
Other Pages
259
Notes
LR: 20131121; JID: 9608387; 059QF0KO0R (Water); EIN: East Mediterr Health J. 2008 Sep-Oct;14(5):1224. Rayah, E El-A [corrected to El Rayah, A E]; ppublish
Place of Publication
Egypt
ISSN/ISBN
1020-3397; 1020-3397
Accession Number
PMID: 18561715
Language
eng
SubFile
Journal Article; IM
DOI
Output Language
Unknown(0)
PMID
18561715
Abstract
Anopheles arabiensis breeding was studied during March 1999-June 2000 in New Halfa town. Of 3642 anopheline larvae collected, 3633 (99.75%) were A. arabiensis: 82.49%, 11.56%, 3.08% and 2.88% of the larvae were collected from shallow sunlit pools resulting from pipes leakages, rain pools, irrigation canals and man-made pools respectively. The overall mean density was 24.34 larvae/10 dips: 40.73 during the rainy season, 30.45 during irrigation and 13.10 in the dry season. Water for crop cultivation increased the relative humidity (P = 0.013) and both factors enhanced A. arabiensis breeding (P < 0.005). There was no significant difference between the rainy and irrigation seasons. A. arabiensis breeding in this area has become perennial as a result of crop irrigation.
Descriptors
Agriculture, Analysis of Variance, Animals, Anopheles/parasitology/physiology, Climate, Ecology, Ecosystem, Humans, Humidity, Insect Vectors/parasitology/physiology, Larva/physiology, Malaria, Falciparum/epidemiology/prevention & control/transmission, Mosquito Control, Population Density, Rain, Reproduction/physiology, Seasons, Sudan/epidemiology, Urban Health/statistics & numerical data, Water/parasitology, Water Supply
Links
Book Title
Database
Publisher
Data Source
Authors
Himeidan,Y. E., El Rayah,A. E.
Original/Translated Title
URL
Date of Electronic
PMCID
Editors
Role of World Health Organization Framework Convention on Tobacco Control Global Knowledge Hub on Smokeless Tobacco 2018 WHO FCTC Global Knowledge Hub on Smokeless Tobacco, ICMR-National Institute of Cancer Prevention & Research, Noida, India.; WHO FCTC Global Knowledge Hub on Smokeless Tobacco, ICMR-National Institute of Cancer Prevention & Research, Noida, India(TRUNCATED
Source Type
Print(0)
Ref Type
Journal Article
Periodical, Full
The Indian journal of medical research
Periodical, Abbrev.
Indian J.Med.Res.
Pub Date Free Form
Jul
Volume
148
Issue
1
Start Page
7
Other Pages
13
Notes
LR: 20181211; JID: 0374701; OTO: NOTNLM; 2018/09/29 06:00 [entrez]; 2018/09/29 06:00 [pubmed]; 2018/12/12 06:00 [medline]; ppublish
Place of Publication
India
ISSN/ISBN
0971-5916; 0971-5916
Accession Number
PMID: 30264749
Language
eng
SubFile
Journal Article; Review; IM
DOI
10.4103/ijmr.IJMR_2036_17 [doi]
Output Language
Unknown(0)
PMID
30264749
Abstract
Smokeless tobacco (SLT) is a recognized public health challenge, having over 350 million users globally, concentrated particularly in South-East Asia. A need for research on curbing major challenges in regulating SLT use has been long felt and subsequently highlighted in several sessions of the Conference of Parties (COP) of the Framework Convention on Tobacco Control (FCTC). The sixth session of COP established a knowledge hub on SLT at the Indian Council of Medical Research- National Institute of Cancer Prevention and Research India, with a mandate to (i) generate and share expertise, information and knowledge; (ii) promote and facilitate communication among Parties, organizations and stakeholders; and (iii) support the Convention Secretariat in contributing to technical aspects of SLT control. The hub disseminates scientific evidence through an interactive website and publications and supports national and international partners in SLT research. The hub is a contributor to many events/conferences and has conducted several workshops on SLT control, including an inter-country meeting on SLT policy implementation status, which brought together representatives from across the globe, and framed recommendations for policy reform. The hub is dedicated to interaction and collaboration with relevant tobacco control organizations to generate evidence, support and policy orientation in line with its mandates and recommendations under the World Health Organization FCTC.
Descriptors
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Book Title
Database
Publisher
Data Source
Authors
Mehrotra,R., Grover,S., Chandra,A.
Original/Translated Title
URL
Date of Electronic
PMCID
PMC6172919
Editors
Roll-your-own tobacco use among Canadian youth: is it a bigger problem than we think? 2012 School of Public Health and Health Systems, University of Waterloo, Waterloo, ON, Canada, N2L 3G1. sleather@uwaterloo.ca
Source Type
Print(0)
Ref Type
Journal Article
Periodical, Full
BMC public health
Periodical, Abbrev.
BMC Public Health
Pub Date Free Form
27-Jul
Volume
12
Issue
Start Page
557
Other Pages
2458-12-557
Notes
LR: 20150224; JID: 100968562; OID: NLM: PMC3434020; 2012/03/26 [received]; 2012/07/03 [accepted]; 2012/07/27 [aheadofprint]; epublish
Place of Publication
England
ISSN/ISBN
1471-2458; 1471-2458
Accession Number
PMID: 22834563
Language
eng
SubFile
Journal Article; Research Support, Non-U.S. Gov't; IM
DOI
10.1186/1471-2458-12-557 [doi]
Output Language
Unknown(0)
PMID
22834563
Abstract
BACKGROUND: Despite the apparent decline in the popularity of roll-your-own (RYO) cigarettes over the past few decades, RYO tobacco products are widely available and used by a substantial number of adult smokers. Considering research has yet to examine the prevalence of RYO tobacco use among youth populations, this manuscript examines the prevalence of RYO tobacco use and factors associated with RYO use in a nationally representative sample of youth smokers from Canada. METHODS: This study used data collected from 3,630 current smokers in grades 9 to 12 as part of the 2008-09 Canadian Youth Smoking Survey (YSS). Descriptive analyses of the sample demographic characteristics, smoking status, cigarettes per day, weekly spending money, and frequency of marijuana use were examined by RYO tobacco ever use and RYO tobacco current use. Two logistic regression models were used to examine factors associated with RYO tobacco ever use and RYO tobacco current use. RESULTS: We identified that 51.2% of current smokers were RYO ever users and 24.2% were RYO current users. The prevalence of RYO current users was highest in Atlantic Canada (40.1%) and lowest in Quebec (12.3%). RYO current users were more likely to be male (OR 1.27), to be daily smokers (OR 1.75), to use marijuana once a month or more (OR 2.74), and to smoke 11 or more cigarettes per day (OR 6.52). RYO current users were less likely to be in grade 11 (OR 0.65) or grade 12 (OR 0.40) and less likely to have between $20 to $100 (OR 0.44) or more than $100 (OR 0.45) of disposable income. CONCLUSIONS: Developing a better understanding of RYO tobacco use among youth is important for advancing population-level tobacco control prevention strategies and cessation programs. We identified that RYO tobacco use is not a negligible problem among Canadian youth. Ongoing research is needed to continue monitoring the prevalence of RYO use among youth and the factors associated with its use, but to also monitor if this more affordable tobacco product is being targeted to price sensitive youth smokers.
Descriptors
Links
Book Title
Database
Publisher
Data Source
Authors
Leatherdale,S.T., Burkhalter,R.
Original/Translated Title
URL
Date of Electronic
20120727
PMCID
PMC3434020
Editors
Root and shoot growth, assimilate partitioning and cell proliferation in roots of sitka spruce (Picea sitchensis) grown in filtered and unfiltered chambers 1996 Bambridge, L., Biochemistry Physiology Department, Rothamsted Experimental Station, Harpenden, Herts. AL5 2JQ, United Kingdom
Source Type
Print(0)
Ref Type
Journal Article
Periodical, Full
Environmental Pollution
Periodical, Abbrev.
Environ.Pollut.
Pub Date Free Form
1996/
Volume
92
Issue
3
Start Page
343
Other Pages
347
Notes
Place of Publication
ISSN/ISBN
0269-7491
Accession Number
Language
SubFile
DOI
Output Language
Unknown(0)
PMID
Abstract
Rooted cuttings of clonal Sitka spruce (Picea sitchensis (Bong.) Carr.) were grown from April to October in 1 m long tubes sunk into the ground inside open top chambers. The same experiment was repeated in each of two consecutive years using a different clone of Sitka spruce each year. Air was either passed directly into the chambers (ambient ail) or passed over charcoal filters which removed the majority of gaseous pollutants before entering the chambers (filtered air). Ambient pollution did not appear to influence the growth of Sitka spruce at least over the experimental period used. No significant differences were found between plants exposed to ambient or filtered air in terms of shoot and root dry mass, needle dry mass, root length, carbohydrate content of roots and needles, and in the percentage of meristematic cells close to the apex in each phase or interphase or undergoing mitosis.
Descriptors
carbohydrate, charcoal, air pollutant, article, carbohydrate analysis, cell count, cell proliferation, clone, experiment, forestry, mass, mitosis, plant growth, plant root, pollution control, tree
Links
Book Title
Database
Embase
Publisher
Data Source
Embase
Authors
Bambridge,L., Harmer,R., Macleod,R.
Original/Translated Title
URL
Date of Electronic
PMCID
Editors
Root proliferation of Norway spruce and Scots pine in response to local magnesium supply in soil 2009 College of Resources and Environmental Sciences, China Agricultural University, Beijing 100094, P.R. China. junlingz@cau.edu.cn
Source Type
Print(0)
Ref Type
Journal Article
Periodical, Full
Tree physiology
Periodical, Abbrev.
Tree Physiol.
Pub Date Free Form
Feb
Volume
29
Issue
2
Start Page
199
Other Pages
206
Notes
LR: 20131121; JID: 100955338; 0 (Soil); 27YLU75U4W (Phosphorus); I38ZP9992A (Magnesium); N762921K75 (Nitrogen); RWP5GA015D (Potassium); 2008/12/05 [aheadofprint]; ppublish
Place of Publication
Canada
ISSN/ISBN
0829-318X; 0829-318X
Accession Number
PMID: 19203945
Language
eng
SubFile
Journal Article; Research Support, Non-U.S. Gov't; IM
DOI
10.1093/treephys/tpn016 [doi]
Output Language
Unknown(0)
PMID
19203945
Abstract
Nutrient sources in soils are often heterogeneously distributed. Although many studies have examined the root responses to local N and P enrichments in the soil, less research was conducted on root responses to Mg patches. New roots of pre-grown Mg-insufficient and Mg-sufficient plants of Norway spruce (Picea abies [L.] Karst.) and Scots pine (Pinus sylvestris L.) seedlings were allowed to grow into four other pots of equal size, which were placed under the tree-bearing pot. Soils in the lower pots were either unfertilised, or supplied with Mg, or NPK or a mixture of NPKMg sources. Plants were harvested after 9 months of growth. Compared to the corresponding controls (Mg versus unfertilised and NPKMg versus NPK), Mg additions did not have a significant effect on either root dry matter, total root length (TRL) or specific root length (SRL), irrespective of tree species and plant Mg nutritional status. In contrast, NPK and NPKMg additions significantly increased the root dry matter and TRL in the nutrient-rich soil patch, and decreased SRL in Norway spruce. However, the observed root morphological changes did not occur in Scots pine. Root Mg concentrations were increased in Mg-rich soil patches, but those accumulations varied with tree species. Mg accumulation in a marked patch was measured only in newly grown roots of Mg-sufficient Norway spruce, whereas a more homogenous distribution of Mg concentration was observed for all newly grown roots in Mg-insufficient trees in the four soil treatments. In Scots pine, Mg accumulations occurred in both Mg-insufficient and Mg-sufficient plants. These results suggest that Mg patches in the soil may not lead to a local increase in root growth, but to Mg uptake and root Mg accumulation. Tree roots react differently to Mg patches in comparison to their response to N or P patches in the soil.
Descriptors
Biological Transport, Magnesium/metabolism, Nitrogen/metabolism, Phosphorus/metabolism, Picea/growth & development/metabolism, Pinus sylvestris/growth & development/metabolism, Plant Leaves/physiology, Plant Roots/growth & development/metabolism, Plant Shoots/physiology, Potassium/metabolism, Soil, Trees/growth & development
Links
Book Title
Database
Publisher
Data Source
Authors
Zhang,J., George,E.
Original/Translated Title
URL
Date of Electronic
20081205
PMCID
Editors
Routine prophylaxes every 3 months improves chronic periodontitis status in type 2 diabetes 2014 Currently, Department of Research and Postgraduate Studies, Faculty of Dentistry, University Andres Bello, Santiago, Chile; previously, Department of Conservative Dentistry, Faculty of Dentistry, University of Chile, Santiago, Chile.
Source Type
Print(0)
Ref Type
Journal Article
Periodical, Full
Journal of periodontology
Periodical, Abbrev.
J.Periodontol.
Pub Date Free Form
Jul
Volume
85
Issue
7
Start Page
e232
Other Pages
40
Notes
JID: 8000345; 0 (Hemoglobin A, Glycosylated); 0 (Hypoglycemic Agents); OTO: NOTNLM; 2013/12/19 [aheadofprint]; ppublish
Place of Publication
United States
ISSN/ISBN
1943-3670; 0022-3492
Accession Number
PMID: 24354651
Language
eng
SubFile
Comparative Study; Controlled Clinical Trial; Journal Article; Research Support, Non-U.S. Gov't; D; IM
DOI
10.1902/jop.2013.130400 [doi]
Output Language
Unknown(0)
PMID
24354651
Abstract
BACKGROUND: Periodontitis and type 2 diabetes mellitus (T2DM) are major health problems, especially in low-income populations with little access to dental care. Low-cost models for treatment of periodontal disease have not been tested in controlled studies in low-income populations. Dental prophylaxis, which includes removal of supragingival calculus and plaque, has been shown to arrest the progression of periodontitis. A controlled clinical trial was conducted to determine the effect of dental prophylaxis on periodontitis in T2DM. METHODS: Twenty-six patients with T2DM and chronic periodontitis (CP) and 26 without T2DM with CP were selected. Periodontal probing depth (PD), gingival bleeding on probing (BOP), clinical attachment level (CAL), and surfaces with plaque were recorded at baseline and 3, 6, and 9 months after initial treatment. All the participants received instructions on oral hygiene and one session of dental prophylaxis at baseline and every 3 months. Glycated hemoglobin (HbA1c) levels were measured at baseline and every 3 months in patients with T2DM. RESULTS: A significant improvement of PD, BOP, and sites with plaque was observed 3 months after treatment in patients with T2DM (P = 0.001). In controls, mean PD significantly improved after 6 months compared with baseline (P = 0.001). No significant improvement of CAL occurred in either group. No significant differences in periodontal parameters between the groups were detected, and no participant showed progression of CP during the 9-month study period. Dental prophylaxis did not influence HbA1c levels, and no association among HbA1c concentration, pretreatment metabolic status, and severity of CP was found. CONCLUSION: Routine prophylaxes every 3 months significantly improve periodontal health and prevent progression of CP in both poorly controlled and well-controlled patients with T2DM.
Descriptors
Links
Book Title
Database
Publisher
Data Source
Authors
Lopez,N.J., Quintero,A., Casanova,P.A., Martinez,B.
Original/Translated Title
URL
Date of Electronic
20131219
PMCID
Editors
Saccharomyces cerevisiae biofilm tolerance towards systemic antifungals depends on growth phase 2014 Department of Systems Biology, Technical University of Denmark, Kgs, Lyngby, Denmark. rakb@vet.dtu.dk.
Source Type
Print(0)
Ref Type
Journal Article
Periodical, Full
BMC microbiology
Periodical, Abbrev.
BMC Microbiol.
Pub Date Free Form
4-Dec
Volume
14
Issue
Start Page
305
Other Pages
014-0305-4
Notes
LR: 20151028; JID: 100966981; 0 (Antifungal Agents); OID: NLM: PMC4258017; 2014/07/25 [received]; 2014/11/20 [accepted]; 2014/12/04 [aheadofprint]; epublish
Place of Publication
England
ISSN/ISBN
1471-2180; 1471-2180
Accession Number
PMID: 25472667
Language
eng
SubFile
Journal Article; Research Support, Non-U.S. Gov't; IM
DOI
10.1186/s12866-014-0305-4 [doi]
Output Language
Unknown(0)
PMID
25472667
Abstract
BACKGROUND: Biofilm-forming Candida species cause infections that can be difficult to eradicate, possibly because of antifungal drug tolerance mechanisms specific to biofilms. In spite of decades of research, the connection between biofilm and drug tolerance is not fully understood. RESULTS: We used Saccharomyces cerevisiae as a model for drug susceptibility of yeast biofilms. Confocal laser scanning microscopy showed that S. cerevisiae and C. glabrata form similarly structured biofilms and that the viable cell numbers were significantly reduced by treatment of mature biofilms with amphotericin B but not voriconazole, flucytosine, or caspofungin. We showed that metabolic activity in yeast biofilm cells decreased with time, as visualized by FUN-1 staining, and mature, 48-hour biofilms contained cells with slow metabolism and limited growth. Time-kill studies showed that in exponentially growing planktonic cells, voriconazole had limited antifungal activity, flucytosine was fungistatic, caspofungin and amphotericin B were fungicidal. In growth-arrested cells, only amphotericin B had antifungal activity. Confocal microscopy and colony count viability assays revealed that the response of growing biofilms to antifungal drugs was similar to the response of exponentially growing planktonic cells. The response in mature biofilm was similar to that of non-growing planktonic cells. These results confirmed the importance of growth phase on drug efficacy. CONCLUSIONS: We showed that in vitro susceptibility to antifungal drugs was independent of biofilm or planktonic growth mode. Instead, drug tolerance was a consequence of growth arrest achievable by both planktonic and biofilm populations. Our results suggest that efficient strategies for treatment of yeast biofilm might be developed by targeting of non-dividing cells.
Descriptors
Links
Book Title
Database
Publisher
Data Source
Authors
Bojsen,R., Regenberg,B., Folkesson,A.
Original/Translated Title
URL
Date of Electronic
20141204
PMCID
PMC4258017
Editors