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1.
Int J Womens Health ; 15: 623-633, 2023.
Article in English | MEDLINE | ID: mdl-37096173

ABSTRACT

Introduction: Intimate partner violence (IPV) is a growing hot topic in Saudi Arabia and primary health care (PHC) physicians play a significant role in preventing it. Our objective was to assess the PHC Physicians' readiness and barriers to identify, screen, and respond to IPV in Saudi Arabia. Methods: A cross-sectional study recruited physicians working in PHC centers in Saudi Arabia. Data was collected using a modified online self-administered questionnaire based on the PREMIS "The Physician Readiness to Identify and Manage IPV." The questionnaire consisted of respondent profile, perceived preparedness and knowledge, actual knowledge, practice issues, and opinion regarding barriers. Results: Among 169 PHC physicians, 60.9% had never experienced any formal IPV training. Around one-fifth of participants have a good perceived and actual knowledge, whereas one-third have a good perceived preparedness. Nearly half of the participants (46.7%) do not screen for IPV and two-thirds of them (66.3%) have never identified an IPV case during the previous 6 months. The logistic regression model showed that family physicians were 2.27 times more likely to have a good knowledge than a general practitioner, and participants with IPV training were more likely to have a good level of perceived preparedness, perceived knowledge, and more likely to perform screening of IPV. Conclusion: The low level of PHC physicians' readiness to identify and respond to IPV is worrisome. Findings emphasize the urgent need for an IPV training program, a supportive work environment, and a clear referral system in order to help the practitioner to provide comprehensive services and ensure safety plans for abused women.

2.
Hum Vaccin Immunother ; 18(6): 2132082, 2022 Nov 30.
Article in English | MEDLINE | ID: mdl-36399718

ABSTRACT

Vaccine hesitancy is one of the major global health impedances. Due to the unprecedented developing rate, the COVID-19 vaccine engendered a high level of hesitancy worldwide. The aim of this study is to assess hesitancy of COVID-19 vaccine among healthcare workers in Sudan. An online-based cross-sectional survey was conducted in Sudan between May and June 2021 using conventional sampling. An anonymous online questionnaire was distributed to healthcare workers (HCW) through different social media platforms and 930 healthcare workers agreed to participate. Data were cleaned in excel sheet and then statistically analyzed using R software version 4.0.2. Of total participants, 67.3% of them were females. Over three-fifths of the study participants agreed that COVID-19 vaccine is important and should be mandatory. A total of 570 (61.3%) agreed that COVID-19 vaccines are safe, whilst 584 (62.8%) had concerns regarding side effects of the vaccine and 533 (57.3%) believe insufficient trials were conducted. A total of 375 (40.3%) accept vaccination absolutely, while 292 (31.4%) accept with some hesitation and only 48 (5.2%) refuse absolutely. Insufficient information about side effects (42.6%) and the vaccine (39.9%) were the most common concerns regarding COVID-19 vaccination. Majority of Sudanese healthcare workers believed that COVID-19 vaccination should be mandatory. A high reliance on social media was observed among healthcare workers in Sudan for information on the COVID-19 pandemic.


Subject(s)
COVID-19 , Drug-Related Side Effects and Adverse Reactions , Female , Humans , Male , COVID-19 Vaccines , Cross-Sectional Studies , Pandemics , COVID-19/prevention & control , Vaccination , Health Personnel
3.
Gels ; 8(4)2022 Apr 05.
Article in English | MEDLINE | ID: mdl-35448123

ABSTRACT

The dosimetric characteristics of hydrogel dosimeters based on polyacrylamide (PAC) as a capping agent incorporating silver nitrate as a radiation-sensitive material are investigated using UV-Vis spectrophotometry within the dose range 0-100 Gy. Glycerol was used in the hydrogel matrix to promote the dosimetric response and increase the radiation sensitivity. Upon exposing the PAC hydrogel to γ-ray, it exhibits a Surface Plasmon Resonance (SPR) band at 453 nm, and its intensity increases linearly with absorbed doses up to 100 Gy. The results are compared with the silver nitrate gel dosimeter. Glycerol of 15% in the hydrogel matrix enhances the radiation sensitivity by about 30%. PAC hydrogel dosimeter can be considered a near water equivalent material in the 400 keV-20 MeV photon energy range. At doses less than 15 Gy, the PAC hydrogel dosimeter retains higher radiation sensitivity than the gel dosimeter. The total uncertainty (2σ) of the dose estimated using this hydrogel is about 4%. These results may support the validity of using this hydrogel as a dosimeter to verify radiotherapy techniques and dose monitoring during blood irradiation.

4.
ACS Omega ; 6(39): 25574-25584, 2021 Oct 05.
Article in English | MEDLINE | ID: mdl-34632214

ABSTRACT

A rapid, efficient, and one-pot protocol has been developed for the synthesis of cyclized 2,6-dimethyl-5-substituted-thiazolo[3,2-b]-s-triazoles (3a-c) through the interaction of 5-methyl-1H-s-triazole-3-thiol (1) with aliphatic ketones (2a-d) in refluxing acetic acid in the presence of a catalytic amount of sulfuric acid (AcOH/H+) while with aromatic ketones (5a-d), a mixture of uncyclized 3-methyl-s-triazolylthioacetophenone derivatives (6a-d) and cyclized 6-aryl-2-methyl-thiazolo[3,2-b]-s-triazoles (7a-d) has been produced. With this catalytic system, inexpensive sulfuric acid was utilized as a catalyst, which prevented the production of poisonous and irritating halo carbonyl compounds. On the other hand, the interaction of s-triazole 1 with cyano compounds (9a,b) afforded the corresponding 6-amino-2-methyl-5-substituted-thiazolo[3,2-b]-s-triazoles (10a,b). Similarly, treatment of 4-amino-3-methyl-s-triazole-5-thiol (12) with aliphatic and aromatic ketones (2c and 5a-e) afforded directly 3-methyl-7H-s-triazolo[3,4-b]-1,3,4-thiadiazines (13a and 14a-e). Further, reaction of 12 with cyano compounds (9a,b) under the same reaction conditions yielded the corresponding 3-methyl-s-triazolo[3,4-b]-1,3,4-thiadiazole derivatives (15a,b). The reaction mechanism was studied, and the structures of all novel compounds were verified using spectroscopy and elemental analysis. Moreover, the potential application of the synthesized compounds toward heavy metal ions and inorganic anion removal from aqueous solution has been investigated. The removal effectiveness for metal ions reached up to 76.29%, while for inorganic anions it reached up to 100%, indicating that such synthesized compounds are promising adsorbents for water remediation.

5.
J Ethnopharmacol ; 265: 113188, 2021 Jan 30.
Article in English | MEDLINE | ID: mdl-32783985

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Stevia rebaudiana Bertoni is a perennial herb that belongs to the Asteraceae family. It is a natural sweetener plant known as "Sweet Leaf", "Sweet Herbs" and "Honey Leaf", which is estimated to be 300 times more sweetening than sugar cane. Stevia has been used as a traditional treatment for diabetes in many countries for hundreds of years. Several animal studies referred to the antihyperglycemic activity of stevia. However, the combined use of stevia with saxagliptin has not been studied so far, so this study has been done. The aim of the present study was to evaluate the antihyperglycemic effect of stevia alone and in combination with saxagliptin. MATERIALS AND METHODS: Diabetes was induced in rats by i.p. injection of streptozotocin and nicotinamide. Animals were divided into five groups, each contains eight rats. Group I: included negative controland group II: included diabetic control that received saline. Group III: included diabetic rats that received 400 mg/kg/day stevia aqueous extract. Group IV: included diabetic rats that received saxagliptin 10 mg/kg/day. Group V: included diabetic rats that received stevia 400 mg/kg + saxagliptin 10 mg/kg. Food and water intake were measured daily while body weight was measured weekly. After 3 weeks animals were sacrificed and blood and tissue samples were collected. Fasting blood glucose (FBG), serum insulin, serum dipeptidylepeptidase-4 (DPP-4), TC, TGs, LDL, HDL, GSH and MDA were measured in treated and control rats by colorimetric and ELISA methods. RESULTS: Both stevia and saxagliptin significantly reduced food, water intake, body weight and FBG. Stevia with saxagliptin produced more significant decrease in FBG. While serum insulin increased significantly in stevia, saxagliptin treated groups and their combination. Serum DPP-4 decreased significantly in all treated groups, concerning lipid profile, stevia and saxagliptin notably lowered TC, TGs, and LDL and increased HDL. Both stevia and saxagliptin remarkably decreased MDA and increased GSH compared to diabetic rats. In addition, stevia significantly improved the antidiabetic effects of saxagliptin. CONCLUSION: Stevia has an antihyperglycemic effect and could enhance the antidiabetic activity of saxagliptin. DPP-4 attenuation, antihyperlipidemic and antioxidant activity as well as improvement of insulin sensitivity may be involved in the antidiabetic action of stevia.


Subject(s)
Adamantane/analogs & derivatives , Diabetes Mellitus, Experimental/drug therapy , Dipeptides/pharmacology , Hypoglycemic Agents/pharmacology , Plant Extracts/pharmacology , Stevia/chemistry , Adamantane/administration & dosage , Adamantane/pharmacology , Animals , Antioxidants/isolation & purification , Antioxidants/pharmacology , Blood Glucose/drug effects , Diabetes Mellitus, Experimental/physiopathology , Dipeptides/administration & dosage , Herb-Drug Interactions , Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/isolation & purification , Hypolipidemic Agents/isolation & purification , Hypolipidemic Agents/pharmacology , Insulin Resistance , Male , Niacinamide , Plant Extracts/administration & dosage , Rats , Rats, Wistar , Streptozocin
6.
RSC Adv ; 10(34): 20184-20194, 2020 May 26.
Article in English | MEDLINE | ID: mdl-35520399

ABSTRACT

An efficient, simple, and one-pot double Mannich reaction was performed for the synthesis of cyclized 2-methyl-6-substituted-6,7-dihydro-5H-s-triazolo[5,1-b]-1,3,5-thiadiazines via a reaction of 5-methyl-1H-s-triazole-3-thiol (1) with formaldehyde and primary aliphatic amines in ethanol at room temperature, while with primary aromatic amines, uncyclized 3-methyl-1-((substituted-amino)methyl)-1H-s-triazole-5-thiols were produced. Under Mannich reaction conditions, 4-amino-3-methyl-s-triazole-5-thiol (8) reacted with formaldehyde only in boiling ethanol or at room temperature to afford 3-methyl-5,6-dihydro-s-triazolo[3,4-b]-1,3,4-thiadiazole without incorporation of secondary amine. Furthermore, after reaction of compound 8 with aromatic aldehydes under different reaction conditions, uncyclized Schiff's bases were produced. Therefore, reaction of these Schiff's bases with primary or secondary amines with formaldehyde in ethanol at room temperature afforded the corresponding Mannich bases 13-14. The structures of all new compounds were confirmed using spectral analysis. Furthermore, most of the synthesized derivatives showed high efficiency for removal of Pb2+, Cd2+, Ca2+, and Mg2+ from aqueous solutions, as well as antimicrobial activity.

7.
J Food Prot ; 80(6): 982-989, 2017 06.
Article in English | MEDLINE | ID: mdl-28467188

ABSTRACT

The purpose of the study was to evaluate three real-time PCR platforms for rapid detection of Salmonella from cloves and to compare three different DNA extraction methods. Six trials were conducted with two clove cultivars, Ceylon and Madagascar, and three Salmonella serotypes, Montevideo, Typhimurium, and Weltevreden. Each trial consisted of 20 test portions. The preenrichment cultures were used to perform PCR for comparison of the effectiveness of U.S. Food and Drug Administration, Pacific Regional Laboratory Southwest (FDA-PRLSW), Applied Biosystems Inc. (ABI) MicroSEQ, and GeneDisc platforms for detection of Salmonella. Three DNA extraction methods were used: standard extraction method for each PCR platform, boil preparation, and LyseNow food pathogen DNA extraction cards. The results from real-time PCR correlated well with FDA Bacteriological Analytical Manual culture assay results, with a wide range of cycle threshold (CT) values among the three PCR platforms for intended positive samples. The mean CT values for MicroSEQ (16.36 ± 2.78) were significantly lower than for PRLSW (20.37 ± 3.45) and GeneDisc (23.88 ± 2.90) (P < 0.0001). Pairwise comparisons between PCR platforms using different DNA extraction methods indicate that the CT values are inversely proportional to the relative DNA quantity (RDQ) yields by different platform-extraction combinations. The pairing of MicroSEQ and boil preparation generated the highest RDQ of 120 and the lowest average CT value of 14.48, whereas the pairing of GeneDisc and LyseNow generated the lowest RDQ of 0.18 and the highest average CT of 25.97. Boil preparation yielded higher RDQ than the other extraction methods for all three PCR platforms. Although the MicroSEQ platform generated the lowest CT values, its sensitivity was compromised by narrow separations between the positive and negative samples. The PRLSW platform generated the best segregation between positive and negative groups and is less likely to produce false results. In conclusion, FDA-PRLSW was the most efficient PCR assay for Salmonella detection, and boil preparation was the best method for DNA extraction.


Subject(s)
Real-Time Polymerase Chain Reaction , Syzygium , DNA, Bacterial , Food Microbiology , Polymerase Chain Reaction , Salmonella/genetics , Sensitivity and Specificity , Sri Lanka
8.
J Food Prot ; 80(3): 376-382, 2017 03.
Article in English | MEDLINE | ID: mdl-28199150

ABSTRACT

Detection of Salmonella in some spices, such as cloves, remains a challenge due to their inherent antimicrobial properties. The purpose of this study was to develop an effective detection method for Salmonella from spices using cloves as a model. Two clove varieties, Ceylon and Madagascar, were used in the study. Cloves were inoculated with Salmonella enterica subsp. enterica serotypes Montevideo, Typhimurium, or Weltevreden at about 1, 3, or 6 log CFU/25 g. Two test portion sizes, 10 and 25 g, were compared. After adding Trypticase soy broth (TSB) to the weighed cloves for preenrichment, three preenrichment methods were compared: cloves were left in the TSB for 24 h during preenrichment (PreE1), or the cloves-TSB mixture was shaken vigorously for 30 s (PreE2) or 60 s (PreE3), and the decanted material was transferred to a new bag for 24 h of preenrichment. The rest of the procedures were carried out according to the U.S. Food and Drug Administration Bacteriological Analytical Manual (BAM). At the low inoculation level (<1 log CFU/25 g), the detection rate was low across the three preenrichment methods, with the highest for PreE3 and lowest for PreE1. At the medium and high inoculation levels (3 and 6 log CFU/25 g), all samples from PreE2 and PreE3 were positive for Salmonella , whereas PreE1 produced only 12 positive samples from the 48 samples at the medium inoculation level and 38 positive samples from the 48 samples at the high inoculation level. Therefore, PreE3 with 25 g of cloves per sample was more effective than the other two tested methods. This newly designed method was then validated by comparing with the BAM method in six trials, with each trial consisting of 40 test samples. The results showed that PreE3 detected Salmonella from 88 of 120 inoculated test samples compared with only 31 positive from 120 test samples with the BAM method. Thus, our newly designed method PreE3 was more sensitive and easier to operate than the current BAM method for detection of Salmonella in cloves.


Subject(s)
Food Microbiology , Syzygium , Humans , Salmonella/isolation & purification , Salmonella enterica/isolation & purification , Sri Lanka
9.
Int J Food Microbiol ; 241: 15-22, 2017 Jan 16.
Article in English | MEDLINE | ID: mdl-27741432

ABSTRACT

A precise and accurate method for enumeration of low level of Listeria monocytogenes in foods is critical to a variety of studies. In this study, paired comparison of most probable number (MPN) and direct plating enumeration of L. monocytogenes was conducted on a total of 1730 outbreak-associated ice cream samples that were naturally contaminated with low level of L. monocytogenes. MPN was performed on all 1730 samples. Direct plating was performed on all samples using the RAPID'L.mono (RLM) agar (1600 samples) and agar Listeria Ottaviani and Agosti (ALOA; 130 samples). Probabilistic analysis with Bayesian inference model was used to compare paired direct plating and MPN estimates of L. monocytogenes in ice cream samples because assumptions implicit in ordinary least squares (OLS) linear regression analyses were not met for such a comparison. The probabilistic analysis revealed good agreement between the MPN and direct plating estimates, and this agreement showed that the MPN schemes and direct plating schemes using ALOA or RLM evaluated in the present study were suitable for enumerating low levels of L. monocytogenes in these ice cream samples. The statistical analysis further revealed that OLS linear regression analyses of direct plating and MPN data did introduce bias that incorrectly characterized systematic differences between estimates from the two methods.


Subject(s)
Colony Count, Microbial/methods , Food Contamination/analysis , Food Microbiology , Ice Cream/microbiology , Listeria monocytogenes/isolation & purification , Agar , Algorithms , Bayes Theorem , Culture Media , Least-Squares Analysis , Limit of Detection , Polymerase Chain Reaction , Probability , Reproducibility of Results
10.
J Food Prot ; 79(11): 1828-1832, 2016 11.
Article in English | MEDLINE | ID: mdl-28221903

ABSTRACT

A most-probable-number (MPN) method was used to enumerate Listeria monocytogenes in 2,320 commercial ice cream scoops manufactured on a production line that was implicated in a 2015 listeriosis outbreak in the United States. The analyzed samples were collected from seven lots produced in November 2014, December 2014, January 2015, and March 2015. L. monocytogenes was detected in 99% (2,307 of 2,320) of the tested samples (lower limit of detection, 0.03 MPN/g), 92% of which were contaminated at <20 MPN/g. The levels of L. monocytogenes in these samples had a geometric mean per lot of 0.15 to 7.1 MPN/g. The prevalence and enumeration data from an unprecedented large number of naturally contaminated ice cream products linked to a listeriosis outbreak provided a unique data set for further understanding the risk associated with L. monocytogenes contamination for highly susceptible populations.


Subject(s)
Ice Cream , Listeria monocytogenes , Disease Outbreaks , Food Contamination , Food Microbiology , Listeriosis , Prevalence , United States
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 117: 587-97, 2014 Jan 03.
Article in English | MEDLINE | ID: mdl-24103229

ABSTRACT

The electronic absorption spectra of 6-ethyl-4-hydroxy-2,5-dioxo-pyrano[3,2-c] quinoline 1, 6-ethyl-4-hydroxy-3-nitro-2,5-dioxo-pyrano[3,2-c] quinoline 2, 6-ethyl-4-chloro-2,5-dioxo-pyrano[3,2-c] quinoline 3, 6-ethyl-3-nitro-4-chloro-2,5-dioxo-pyrano[3,2-c] quinoline 4, 6-ethyl-4,5-dioxopyrano[3,2-c] quinoline 5, and 6-ethyl-3-nitro-6H-pyrano [3,2-c]quinoline-4,5-dione 6, were measured in polar (methanol) as well as nonpolar (dioxane) solvents. The geometries were optimized using B3LYB/6-311G (p,d) method. The most stable geometry of the studied compounds, 1-6, is the planar structure as indicates by the values of the dihedral angles. The insertion of a nitro group in position 3 in both α- and γ-pyrone ring decreases the energy gap and hence increases the reactivity of 3 and 6 compounds. Assignment of the observed bands as localized, delocalized and/or of charge transfer (CT) has been facilitated by TD-DFT calculations. The correspondences between the calculated and experimental transition energies are satisfactory. The solvent and substituent effects have been investigated. Chloro-substituent has a higher band position and intensity effects on the spectra more than hydroxyl or nitro groups.


Subject(s)
Electrons , Pyrones/chemistry , Quantum Theory , Solvents/chemistry , Spectrophotometry, Ultraviolet , Absorption , Models, Molecular
12.
J Med Entomol ; 49(3): 547-54, 2012 May.
Article in English | MEDLINE | ID: mdl-22679861

ABSTRACT

Ticks are efficient ectoparasites that are able to steal blood, a rich source of nutrients, from their vertebrate hosts. The nymphal developmental stage of ticks plays an important role for pathogen transmission to human and other animal hosts. In this article, we describe a bloodmeal-based sex differentiation tool to generate adult female ticks infected with Ehrlichia chaffeensis to investigate vector-pathogen interactions (functional genomics and gene expression studies). We demonstrate that there is a correlation between the uptake of blood during nymph attachment and the molting into male or female adult ticks. The data obtained from the bloodmeal experiments suggest that nymphs that molt into females presumably imbibe more blood than those that become male during the nymphal stage. The natural low E. chaffeensis infection rate in female adult Amblyomma americanum (L.) is a major limiting factor to investigate Ehrlichia-Amblyomma interactions. To generate Ehrlichia-infected female adult ticks, we inoculated obligate E. chaffeensis (Arkansas strain) infected DH82 cells into heavier engorged nymphs (> 12 mg) and allowed them to molt. Freshly molted adults were used to test the E. chaffeensis infection rate. E. chaffeensis genomic DNA was extracted from individual unfed and partially blood fed tick midgut and salivary gland tissues. The tissue samples were tested for the presence of E. chaffeensis using the nested polymerase chain reaction process. Polymerase chain reaction-amplified fragments were detected in unfed and partially fed tissues, demonstrating successful E. chaffeensis infection of tick tissues. This method was used to successfully show differential expression of selected tick genes in E. chaffeensis-infected midguts and salivary glands.


Subject(s)
Ehrlichia chaffeensis/physiology , Ixodidae/microbiology , Salivary Glands/microbiology , Animals , Arthropod Vectors/microbiology , Arthropod Vectors/physiology , Cricetinae , Female , Gene Expression , Ixodidae/physiology , Male , Nymph/microbiology , Rabbits
13.
J AOAC Int ; 91(2): 383-6, 2008.
Article in English | MEDLINE | ID: mdl-18476352

ABSTRACT

A method is described for determining coumarin, vanillin, and ethyl vanillin in vanilla extract products. A product is diluted one-thousand-fold and then analyzed by reversed-phase liquid chromatography using a C18 column and a mobile phase consisting of 55% acetonitrile-45% aqueous acetic acid (1%) solution at a flow rate of 1.0 mL/min. Peaks are detected with a UV detector set at 275 nm. Vanilla extracts were spiked with 250, 500, and 1000 microg/g each of coumarin, vanillin, and ethyl vanillin. Recoveries averaged 97.4, 97.8, and 99.8% for coumarin, vanillin, and ethyl vanillin, respectively, with coefficient of variation values of 1.8, 1.3, and 1.3%, respectively. No significant difference was observed among the 3 spiking levels. A survey of 23 domestic and imported vanilla extract products was conducted using the method. None of the samples contained coumarin. The surveyed samples contained between 0.4 to 13.1 and 0.4 to 2.2 mg/g vanillin and ethyl vanillin, respectively.


Subject(s)
Benzaldehydes/analysis , Chromatography, Liquid/methods , Coumarins/analysis , Plant Extracts/analysis , Vanilla/chemistry , Spectrophotometry, Ultraviolet
14.
Bioresour Technol ; 97(15): 1887-93, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16256346

ABSTRACT

This study investigated the suitability of the Calgary Biofilm Device (CBD), originally designed as a test surrogate for indwelling medical devices, for assessing the efficacy of antimicrobials developed for food and food contact surface disinfection applications. The conditions for the development of uniform biofilms from pure and mixed bacterial cultures of wild type Escherichia coli and Listeria innocua were optimized. We were able to recover approximately 2 x 10(6) colony forming units (CFU) from the biofilms formed on the individual pegs of the device in 24 h. Further, the parameters for the consistent release of the cells from the biofilms were optimized; test showed that the number of cells released was uniform and reproducible. The consistency and reproducibility of the biofilms formed on the pegs was evaluated using scanning electron microscopy and by plate count method. The efficacies of disinfectants on cells residing in biofilms versus planktonic cells were compared. For both species, higher concentrations of disinfectants were needed to eliminate attached cells as compared with planktonic cells. This study establishes the value of the CBD for generating consistent biofilms from either pure or mixed cultures. These biofilms can be used to assess efficacies of disinfectants against cells that have colonized the surfaces of foods and food-processing equipment. Such a system could serve as a standard surrogate for evaluating new disinfectants designed to reduce or eliminate biofilms from food-contact surfaces.


Subject(s)
Anti-Infective Agents/pharmacology , Biofilms/drug effects , Drug Evaluation, Preclinical/methods , Bacterial Adhesion/drug effects , Biofilms/growth & development , Disinfectants/pharmacology , Drug Evaluation, Preclinical/instrumentation , Escherichia coli/drug effects , Escherichia coli/physiology , Listeria/drug effects , Listeria/physiology , Microbial Sensitivity Tests/methods , Reproducibility of Results , Time Factors
15.
Bioresour Technol ; 94(3): 275-83, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15182834

ABSTRACT

Biofilms of a wild type Escherichia coli were grown on 316 stainless steel slides in a nutrient starved medium. The stainless steel surfaces were either polished to a smooth finish or scribed. The scribes consisted of lines and crosses. Biofilm samples were taken after 3, 6, 12, 24 and 48 h of growth. After sampling, the slides were soaked in deionized water or 50 or 200 ppm free chlorine prior to vital staining. Images were captured and the areas of viable and total biofilm were estimated. The individual biofilm patches, circularities, total percentage coverage, and viability percentage coverage were analyzed. The biofilms tended to increase in size between 6 and 24 h. A 3-6 h old biofilm on a polished stainless steel surface detached when 200 ppm sodium hypochlorite was applied. When grown in scribes, the circularity decreased up to 24 h, but thereafter increased. As the film grew older, it detached with or without a sodium hypochlorite treatment from the part of the surface that was polished, but remained in the neighborhood of the scribe. Based on the results, we recommend sanitizing at intervals of less than 12 h for this and similar strains of bacteria and protection of stainless steel surfaces to minimize scratching.


Subject(s)
Biofilms/drug effects , Disinfection/methods , Escherichia coli/drug effects , Polysaccharides, Bacterial/drug effects , Sodium Hypochlorite/toxicity , Stainless Steel , Analysis of Variance , Image Processing, Computer-Assisted , Time Factors
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