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Papers by patricia cruz

Research paper thumbnail of In vitro and clinical evaluation of specific dentifrices for complete denture hygiene

Gerodontology, 2009

Objectives: To study the physical properties of two experimental dentifrices for complete dentur... more Objectives: To study the physical properties of two experimental dentifrices for complete denture hygiene, their effect on denture biofilm removal and antimicrobial properties by means of a clinical trial.Materials and methods: The experimental dentifrices comprised two compositions. One was based on the addition of 1% chloramine T (D1) and the other on the presence of 0.01% fluorosurfactant (D2). Measurements of density, pH, consistency, rheological features and abrasiveness were conducted. Sixty complete denture wearers were randomly assigned to three groups and were instructed to brush their dentures with a specific toothbrush: (1) Water (control); (2) D1; or (3) D2. Each method was used for 21 days. Denture biofilm was disclosed by a 1% neutral red solution and quantified by means of digital photos taken from the internal surface. Microbiological assessment was conducted to quantify Candida sp. and mutans streptococci. Data were evaluated by one-way anova and Tukey HSD, or Kruskal–Wallis (α = 0.05).Results: Both dentifrices decreased biofilm coverage when compared with the control group. D1 was the most efficacious treatment to reduce mutans streptococci, whereas D2 showed an intermediate outcome (anova, p < 0.040). No treatment influenced Candida albicans or non-albicans species (Kruskal–Wallis, p = 0.163 and 0.746, respectively).Conclusion: It can be concluded that brushing complete dentures with the experimental dentifrices tested could be effective for the removal of denture biofilm.

Research paper thumbnail of Effects of mechanical and chemical methods on denture biofilm accumulation

Journal of Oral Rehabilitation, 2007

summary The aim of this study was to quantify biofilm on the internal surface of upper complete ... more summary The aim of this study was to quantify biofilm on the internal surface of upper complete dentures following six possible cleansing methods. Thirty-six edentulous subjects were submitted to a time-series trial and dentures were cleansed according to six methods: (i) rinsing with water; (ii) soaking in an alkaline peroxide solution (Bonyplus); (iii) brushing with dentifrice (Dentu-Creme) and soft Johnson and Johnson’s toothbrush; (iv) combination between soaking and brushing according to methods 2 and 3; (v) brushing with dentifrice (Dentu-Creme) and soft Oral B toothbrush; (vi) combination between soaking and brushing according to methods 2 and 5. Each method was randomly used throughout 21 days. Denture biofilm was disclosed by 1% neutral red solution and quantified by means of digital photos taken from the internal surface. The six methods presented significant differences in percentage of biofilm coverage (repeated measures anova, P < 0·0001). Method 1 showed the highest values, 2 was intermediate and other results were the lowest. The most efficacious approach was 6. Biofilm tended to accumulate predominantly over specific zones of the denture base, but this pattern did not change regardless of the method employed. It can be concluded that brushing alone was more effective than the chemical method employed. The best results were obtained by a combination of methods.

Research paper thumbnail of Effect of Three Methods for Cleaning Dentures on Biofilms Formed In Vitro on Acrylic Resin

Journal of Prosthodontics, 2009

Purpose: The aim of this study was to evaluate the effect of three denture hygiene methods agains... more Purpose: The aim of this study was to evaluate the effect of three denture hygiene methods against different microbial biofilms formed on acrylic resin specimens.Materials and methods: The set (sterile stainless steel basket and specimens) was contaminated (37°C for 48 hours) by a microbial inoculum with 106 colony-forming units (CFU)/ml (standard strains: Staphylococcus aureus, Streptococcus mutans, Escherichia coli, Candida albicans, Pseudomonas aeruginosa, and Enterococcus faecalis; field strains: S. mutans, C. albicans, C. glabrata, and C. tropicalis). After inoculation, specimens were cleansed by the following methods: (1) chemical: immersion in an alkaline peroxide solution (Bonyplus tablets) for 5 minutes; (2) mechanical: brushing with a dentifrice for removable prostheses (Dentu Creme) for 20 seconds; and (3) a combination of chemical and mechanical methods. Specimens were applied onto a Petri plate with appropriate culture medium for 10 minutes. Afterward, the specimens were removed and the plates incubated at 37°C for 48 hours.Results: Chemical, mechanical, and combination methods showed no significant difference in the reduction of CFU for S. aureus, S. mutans (ATCC and field strain), and P. aeruginosa. Mechanical and combination methods were similar and more effective than the chemical method for E. faecalis, C. albicans (ATCC and field strain), and C. glabrata. The combination method was better than the chemical method for E. coli and C. tropicalis, and the mechanical method showed intermediate results.Conclusion: The three denture hygiene methods showed different effects depending on the type of microbial biofilms formed on acrylic base resin specimens.

Research paper thumbnail of In vitro and clinical evaluation of specific dentifrices for complete denture hygiene

Gerodontology, 2009

Objectives: To study the physical properties of two experimental dentifrices for complete dentur... more Objectives: To study the physical properties of two experimental dentifrices for complete denture hygiene, their effect on denture biofilm removal and antimicrobial properties by means of a clinical trial.Materials and methods: The experimental dentifrices comprised two compositions. One was based on the addition of 1% chloramine T (D1) and the other on the presence of 0.01% fluorosurfactant (D2). Measurements of density, pH, consistency, rheological features and abrasiveness were conducted. Sixty complete denture wearers were randomly assigned to three groups and were instructed to brush their dentures with a specific toothbrush: (1) Water (control); (2) D1; or (3) D2. Each method was used for 21 days. Denture biofilm was disclosed by a 1% neutral red solution and quantified by means of digital photos taken from the internal surface. Microbiological assessment was conducted to quantify Candida sp. and mutans streptococci. Data were evaluated by one-way anova and Tukey HSD, or Kruskal–Wallis (α = 0.05).Results: Both dentifrices decreased biofilm coverage when compared with the control group. D1 was the most efficacious treatment to reduce mutans streptococci, whereas D2 showed an intermediate outcome (anova, p < 0.040). No treatment influenced Candida albicans or non-albicans species (Kruskal–Wallis, p = 0.163 and 0.746, respectively).Conclusion: It can be concluded that brushing complete dentures with the experimental dentifrices tested could be effective for the removal of denture biofilm.

Research paper thumbnail of Effects of mechanical and chemical methods on denture biofilm accumulation

Journal of Oral Rehabilitation, 2007

summary The aim of this study was to quantify biofilm on the internal surface of upper complete ... more summary The aim of this study was to quantify biofilm on the internal surface of upper complete dentures following six possible cleansing methods. Thirty-six edentulous subjects were submitted to a time-series trial and dentures were cleansed according to six methods: (i) rinsing with water; (ii) soaking in an alkaline peroxide solution (Bonyplus); (iii) brushing with dentifrice (Dentu-Creme) and soft Johnson and Johnson’s toothbrush; (iv) combination between soaking and brushing according to methods 2 and 3; (v) brushing with dentifrice (Dentu-Creme) and soft Oral B toothbrush; (vi) combination between soaking and brushing according to methods 2 and 5. Each method was randomly used throughout 21 days. Denture biofilm was disclosed by 1% neutral red solution and quantified by means of digital photos taken from the internal surface. The six methods presented significant differences in percentage of biofilm coverage (repeated measures anova, P < 0·0001). Method 1 showed the highest values, 2 was intermediate and other results were the lowest. The most efficacious approach was 6. Biofilm tended to accumulate predominantly over specific zones of the denture base, but this pattern did not change regardless of the method employed. It can be concluded that brushing alone was more effective than the chemical method employed. The best results were obtained by a combination of methods.

Research paper thumbnail of Effect of Three Methods for Cleaning Dentures on Biofilms Formed In Vitro on Acrylic Resin

Journal of Prosthodontics, 2009

Purpose: The aim of this study was to evaluate the effect of three denture hygiene methods agains... more Purpose: The aim of this study was to evaluate the effect of three denture hygiene methods against different microbial biofilms formed on acrylic resin specimens.Materials and methods: The set (sterile stainless steel basket and specimens) was contaminated (37°C for 48 hours) by a microbial inoculum with 106 colony-forming units (CFU)/ml (standard strains: Staphylococcus aureus, Streptococcus mutans, Escherichia coli, Candida albicans, Pseudomonas aeruginosa, and Enterococcus faecalis; field strains: S. mutans, C. albicans, C. glabrata, and C. tropicalis). After inoculation, specimens were cleansed by the following methods: (1) chemical: immersion in an alkaline peroxide solution (Bonyplus tablets) for 5 minutes; (2) mechanical: brushing with a dentifrice for removable prostheses (Dentu Creme) for 20 seconds; and (3) a combination of chemical and mechanical methods. Specimens were applied onto a Petri plate with appropriate culture medium for 10 minutes. Afterward, the specimens were removed and the plates incubated at 37°C for 48 hours.Results: Chemical, mechanical, and combination methods showed no significant difference in the reduction of CFU for S. aureus, S. mutans (ATCC and field strain), and P. aeruginosa. Mechanical and combination methods were similar and more effective than the chemical method for E. faecalis, C. albicans (ATCC and field strain), and C. glabrata. The combination method was better than the chemical method for E. coli and C. tropicalis, and the mechanical method showed intermediate results.Conclusion: The three denture hygiene methods showed different effects depending on the type of microbial biofilms formed on acrylic base resin specimens.

Research paper thumbnail of In vitro and clinical evaluation of specific dentifrices for complete denture hygiene

Gerodontology, 2009

Objectives: To study the physical properties of two experimental dentifrices for complete dentur... more Objectives: To study the physical properties of two experimental dentifrices for complete denture hygiene, their effect on denture biofilm removal and antimicrobial properties by means of a clinical trial.Materials and methods: The experimental dentifrices comprised two compositions. One was based on the addition of 1% chloramine T (D1) and the other on the presence of 0.01% fluorosurfactant (D2). Measurements of density, pH, consistency, rheological features and abrasiveness were conducted. Sixty complete denture wearers were randomly assigned to three groups and were instructed to brush their dentures with a specific toothbrush: (1) Water (control); (2) D1; or (3) D2. Each method was used for 21 days. Denture biofilm was disclosed by a 1% neutral red solution and quantified by means of digital photos taken from the internal surface. Microbiological assessment was conducted to quantify Candida sp. and mutans streptococci. Data were evaluated by one-way anova and Tukey HSD, or Kruskal–Wallis (α = 0.05).Results: Both dentifrices decreased biofilm coverage when compared with the control group. D1 was the most efficacious treatment to reduce mutans streptococci, whereas D2 showed an intermediate outcome (anova, p < 0.040). No treatment influenced Candida albicans or non-albicans species (Kruskal–Wallis, p = 0.163 and 0.746, respectively).Conclusion: It can be concluded that brushing complete dentures with the experimental dentifrices tested could be effective for the removal of denture biofilm.

Research paper thumbnail of Effects of mechanical and chemical methods on denture biofilm accumulation

Journal of Oral Rehabilitation, 2007

summary The aim of this study was to quantify biofilm on the internal surface of upper complete ... more summary The aim of this study was to quantify biofilm on the internal surface of upper complete dentures following six possible cleansing methods. Thirty-six edentulous subjects were submitted to a time-series trial and dentures were cleansed according to six methods: (i) rinsing with water; (ii) soaking in an alkaline peroxide solution (Bonyplus); (iii) brushing with dentifrice (Dentu-Creme) and soft Johnson and Johnson’s toothbrush; (iv) combination between soaking and brushing according to methods 2 and 3; (v) brushing with dentifrice (Dentu-Creme) and soft Oral B toothbrush; (vi) combination between soaking and brushing according to methods 2 and 5. Each method was randomly used throughout 21 days. Denture biofilm was disclosed by 1% neutral red solution and quantified by means of digital photos taken from the internal surface. The six methods presented significant differences in percentage of biofilm coverage (repeated measures anova, P < 0·0001). Method 1 showed the highest values, 2 was intermediate and other results were the lowest. The most efficacious approach was 6. Biofilm tended to accumulate predominantly over specific zones of the denture base, but this pattern did not change regardless of the method employed. It can be concluded that brushing alone was more effective than the chemical method employed. The best results were obtained by a combination of methods.

Research paper thumbnail of Effect of Three Methods for Cleaning Dentures on Biofilms Formed In Vitro on Acrylic Resin

Journal of Prosthodontics, 2009

Purpose: The aim of this study was to evaluate the effect of three denture hygiene methods agains... more Purpose: The aim of this study was to evaluate the effect of three denture hygiene methods against different microbial biofilms formed on acrylic resin specimens.Materials and methods: The set (sterile stainless steel basket and specimens) was contaminated (37°C for 48 hours) by a microbial inoculum with 106 colony-forming units (CFU)/ml (standard strains: Staphylococcus aureus, Streptococcus mutans, Escherichia coli, Candida albicans, Pseudomonas aeruginosa, and Enterococcus faecalis; field strains: S. mutans, C. albicans, C. glabrata, and C. tropicalis). After inoculation, specimens were cleansed by the following methods: (1) chemical: immersion in an alkaline peroxide solution (Bonyplus tablets) for 5 minutes; (2) mechanical: brushing with a dentifrice for removable prostheses (Dentu Creme) for 20 seconds; and (3) a combination of chemical and mechanical methods. Specimens were applied onto a Petri plate with appropriate culture medium for 10 minutes. Afterward, the specimens were removed and the plates incubated at 37°C for 48 hours.Results: Chemical, mechanical, and combination methods showed no significant difference in the reduction of CFU for S. aureus, S. mutans (ATCC and field strain), and P. aeruginosa. Mechanical and combination methods were similar and more effective than the chemical method for E. faecalis, C. albicans (ATCC and field strain), and C. glabrata. The combination method was better than the chemical method for E. coli and C. tropicalis, and the mechanical method showed intermediate results.Conclusion: The three denture hygiene methods showed different effects depending on the type of microbial biofilms formed on acrylic base resin specimens.

Research paper thumbnail of New Targets in Diarrhetic Shellfish Poisoning Control

Journal of Natural Products, 2005

The toxic profile of dinoflagellates varies even among identical species, raising an interesting ... more The toxic profile of dinoflagellates varies even among identical species, raising an interesting question about the mechanism of toxin regulation and production. In consequence, it also poses a considerable problem in their control methods. In this paper, we report on the isolation and structural elucidation of several new ester derivatives of okadaic acid (OA) from artificial cultures of the genus Prorocentrum. These new compounds enlarge the range of target molecules that must be considered in the monitoring programs.

Research paper thumbnail of Identification and characterization of DTX-5c and 7-hydroxymethyl-2-methylene-octa-4,7-dienyl okadaate from Prorocentrum belizeanum cultures by LC–MS

Toxicon, 2007

The main toxins produced by the dinoflagellate Prorocentrum belizeanum, DTX5c and 7-hydroxymethyl... more The main toxins produced by the dinoflagellate Prorocentrum belizeanum, DTX5c and 7-hydroxymethyl-2methyleneocta-4,7 dienyl okadaate, were studied by liquid chromatography-coupled with ion trap mass spectrometry (LC-MS/MS). Their retention times (RTs) and fragmentation patterns were established, in particular those of DTX5c, as there is a lack of data about these water soluble OA sulphated derivatives. As an application of the LC-MS methodology, a sample of the toxic P. belizeanum culture was analysed for these metabolites. Both metabolites were detected in cells as majority compounds, whereas levels of these compounds in the culture media were undetectable. r (J.M. Franco), jjfercas@ull.es (J.J. Ferna´ndez).

Research paper thumbnail of DTX5c, a new OA sulphate ester derivative from cultures of Prorocentrum belizeanum

Toxicon, 2006

Prorocentrum belizeanum is a dinoflagellate known for its okadaic acid (OA) and dinophysitoxins (... more Prorocentrum belizeanum is a dinoflagellate known for its okadaic acid (OA) and dinophysitoxins (DTXs) production, both OA and DTX are polyether toxins of the Diarrhetic Shellfish Poisoning (DSP) group. We have recently published the isolation of a new diol-ester of okadaic acid from cultures of P. belizeanum. On this occasion we present a new sulphated water-soluble derivative, DTX-5c, isolated from this microalga, whose structure was established on the basis of its spectroscopical data. q

Research paper thumbnail of 19- epi -Okadaic Acid, a Novel Protein Phosphatase Inhibitor with Enhanced Selectivity

Organic Letters, 2007

A new protein phosphatase inhibitor, 19-epi-okadaic acid, was isolated from the marine dinoflagel... more A new protein phosphatase inhibitor, 19-epi-okadaic acid, was isolated from the marine dinoflagellate Prorocentrum belizeanum. Its structure and conformation in solution has been determined, and important differences were found when compared with the lead compound okadaic acid. The new metabolite showed nanomolar activities, and its selectivity for PP2A versus PP1 surpasses that shown by okadaic acid 10-fold, making it one of the most selective inhibitors of this class.

Research paper thumbnail of In vitro and clinical evaluation of specific dentifrices for complete denture hygiene

Gerodontology, 2009

Objectives: To study the physical properties of two experimental dentifrices for complete dentur... more Objectives: To study the physical properties of two experimental dentifrices for complete denture hygiene, their effect on denture biofilm removal and antimicrobial properties by means of a clinical trial.Materials and methods: The experimental dentifrices comprised two compositions. One was based on the addition of 1% chloramine T (D1) and the other on the presence of 0.01% fluorosurfactant (D2). Measurements of density, pH, consistency, rheological features and abrasiveness were conducted. Sixty complete denture wearers were randomly assigned to three groups and were instructed to brush their dentures with a specific toothbrush: (1) Water (control); (2) D1; or (3) D2. Each method was used for 21 days. Denture biofilm was disclosed by a 1% neutral red solution and quantified by means of digital photos taken from the internal surface. Microbiological assessment was conducted to quantify Candida sp. and mutans streptococci. Data were evaluated by one-way anova and Tukey HSD, or Kruskal–Wallis (α = 0.05).Results: Both dentifrices decreased biofilm coverage when compared with the control group. D1 was the most efficacious treatment to reduce mutans streptococci, whereas D2 showed an intermediate outcome (anova, p < 0.040). No treatment influenced Candida albicans or non-albicans species (Kruskal–Wallis, p = 0.163 and 0.746, respectively).Conclusion: It can be concluded that brushing complete dentures with the experimental dentifrices tested could be effective for the removal of denture biofilm.

Research paper thumbnail of Effects of mechanical and chemical methods on denture biofilm accumulation

Journal of Oral Rehabilitation, 2007

summary The aim of this study was to quantify biofilm on the internal surface of upper complete ... more summary The aim of this study was to quantify biofilm on the internal surface of upper complete dentures following six possible cleansing methods. Thirty-six edentulous subjects were submitted to a time-series trial and dentures were cleansed according to six methods: (i) rinsing with water; (ii) soaking in an alkaline peroxide solution (Bonyplus); (iii) brushing with dentifrice (Dentu-Creme) and soft Johnson and Johnson’s toothbrush; (iv) combination between soaking and brushing according to methods 2 and 3; (v) brushing with dentifrice (Dentu-Creme) and soft Oral B toothbrush; (vi) combination between soaking and brushing according to methods 2 and 5. Each method was randomly used throughout 21 days. Denture biofilm was disclosed by 1% neutral red solution and quantified by means of digital photos taken from the internal surface. The six methods presented significant differences in percentage of biofilm coverage (repeated measures anova, P < 0·0001). Method 1 showed the highest values, 2 was intermediate and other results were the lowest. The most efficacious approach was 6. Biofilm tended to accumulate predominantly over specific zones of the denture base, but this pattern did not change regardless of the method employed. It can be concluded that brushing alone was more effective than the chemical method employed. The best results were obtained by a combination of methods.

Research paper thumbnail of Effect of Three Methods for Cleaning Dentures on Biofilms Formed In Vitro on Acrylic Resin

Journal of Prosthodontics, 2009

Purpose: The aim of this study was to evaluate the effect of three denture hygiene methods agains... more Purpose: The aim of this study was to evaluate the effect of three denture hygiene methods against different microbial biofilms formed on acrylic resin specimens.Materials and methods: The set (sterile stainless steel basket and specimens) was contaminated (37°C for 48 hours) by a microbial inoculum with 106 colony-forming units (CFU)/ml (standard strains: Staphylococcus aureus, Streptococcus mutans, Escherichia coli, Candida albicans, Pseudomonas aeruginosa, and Enterococcus faecalis; field strains: S. mutans, C. albicans, C. glabrata, and C. tropicalis). After inoculation, specimens were cleansed by the following methods: (1) chemical: immersion in an alkaline peroxide solution (Bonyplus tablets) for 5 minutes; (2) mechanical: brushing with a dentifrice for removable prostheses (Dentu Creme) for 20 seconds; and (3) a combination of chemical and mechanical methods. Specimens were applied onto a Petri plate with appropriate culture medium for 10 minutes. Afterward, the specimens were removed and the plates incubated at 37°C for 48 hours.Results: Chemical, mechanical, and combination methods showed no significant difference in the reduction of CFU for S. aureus, S. mutans (ATCC and field strain), and P. aeruginosa. Mechanical and combination methods were similar and more effective than the chemical method for E. faecalis, C. albicans (ATCC and field strain), and C. glabrata. The combination method was better than the chemical method for E. coli and C. tropicalis, and the mechanical method showed intermediate results.Conclusion: The three denture hygiene methods showed different effects depending on the type of microbial biofilms formed on acrylic base resin specimens.

Research paper thumbnail of In vitro and clinical evaluation of specific dentifrices for complete denture hygiene

Gerodontology, 2009

Objectives: To study the physical properties of two experimental dentifrices for complete dentur... more Objectives: To study the physical properties of two experimental dentifrices for complete denture hygiene, their effect on denture biofilm removal and antimicrobial properties by means of a clinical trial.Materials and methods: The experimental dentifrices comprised two compositions. One was based on the addition of 1% chloramine T (D1) and the other on the presence of 0.01% fluorosurfactant (D2). Measurements of density, pH, consistency, rheological features and abrasiveness were conducted. Sixty complete denture wearers were randomly assigned to three groups and were instructed to brush their dentures with a specific toothbrush: (1) Water (control); (2) D1; or (3) D2. Each method was used for 21 days. Denture biofilm was disclosed by a 1% neutral red solution and quantified by means of digital photos taken from the internal surface. Microbiological assessment was conducted to quantify Candida sp. and mutans streptococci. Data were evaluated by one-way anova and Tukey HSD, or Kruskal–Wallis (α = 0.05).Results: Both dentifrices decreased biofilm coverage when compared with the control group. D1 was the most efficacious treatment to reduce mutans streptococci, whereas D2 showed an intermediate outcome (anova, p < 0.040). No treatment influenced Candida albicans or non-albicans species (Kruskal–Wallis, p = 0.163 and 0.746, respectively).Conclusion: It can be concluded that brushing complete dentures with the experimental dentifrices tested could be effective for the removal of denture biofilm.

Research paper thumbnail of Effects of mechanical and chemical methods on denture biofilm accumulation

Journal of Oral Rehabilitation, 2007

summary The aim of this study was to quantify biofilm on the internal surface of upper complete ... more summary The aim of this study was to quantify biofilm on the internal surface of upper complete dentures following six possible cleansing methods. Thirty-six edentulous subjects were submitted to a time-series trial and dentures were cleansed according to six methods: (i) rinsing with water; (ii) soaking in an alkaline peroxide solution (Bonyplus); (iii) brushing with dentifrice (Dentu-Creme) and soft Johnson and Johnson’s toothbrush; (iv) combination between soaking and brushing according to methods 2 and 3; (v) brushing with dentifrice (Dentu-Creme) and soft Oral B toothbrush; (vi) combination between soaking and brushing according to methods 2 and 5. Each method was randomly used throughout 21 days. Denture biofilm was disclosed by 1% neutral red solution and quantified by means of digital photos taken from the internal surface. The six methods presented significant differences in percentage of biofilm coverage (repeated measures anova, P < 0·0001). Method 1 showed the highest values, 2 was intermediate and other results were the lowest. The most efficacious approach was 6. Biofilm tended to accumulate predominantly over specific zones of the denture base, but this pattern did not change regardless of the method employed. It can be concluded that brushing alone was more effective than the chemical method employed. The best results were obtained by a combination of methods.

Research paper thumbnail of Effect of Three Methods for Cleaning Dentures on Biofilms Formed In Vitro on Acrylic Resin

Journal of Prosthodontics, 2009

Purpose: The aim of this study was to evaluate the effect of three denture hygiene methods agains... more Purpose: The aim of this study was to evaluate the effect of three denture hygiene methods against different microbial biofilms formed on acrylic resin specimens.Materials and methods: The set (sterile stainless steel basket and specimens) was contaminated (37°C for 48 hours) by a microbial inoculum with 106 colony-forming units (CFU)/ml (standard strains: Staphylococcus aureus, Streptococcus mutans, Escherichia coli, Candida albicans, Pseudomonas aeruginosa, and Enterococcus faecalis; field strains: S. mutans, C. albicans, C. glabrata, and C. tropicalis). After inoculation, specimens were cleansed by the following methods: (1) chemical: immersion in an alkaline peroxide solution (Bonyplus tablets) for 5 minutes; (2) mechanical: brushing with a dentifrice for removable prostheses (Dentu Creme) for 20 seconds; and (3) a combination of chemical and mechanical methods. Specimens were applied onto a Petri plate with appropriate culture medium for 10 minutes. Afterward, the specimens were removed and the plates incubated at 37°C for 48 hours.Results: Chemical, mechanical, and combination methods showed no significant difference in the reduction of CFU for S. aureus, S. mutans (ATCC and field strain), and P. aeruginosa. Mechanical and combination methods were similar and more effective than the chemical method for E. faecalis, C. albicans (ATCC and field strain), and C. glabrata. The combination method was better than the chemical method for E. coli and C. tropicalis, and the mechanical method showed intermediate results.Conclusion: The three denture hygiene methods showed different effects depending on the type of microbial biofilms formed on acrylic base resin specimens.

Research paper thumbnail of In vitro and clinical evaluation of specific dentifrices for complete denture hygiene

Gerodontology, 2009

Objectives: To study the physical properties of two experimental dentifrices for complete dentur... more Objectives: To study the physical properties of two experimental dentifrices for complete denture hygiene, their effect on denture biofilm removal and antimicrobial properties by means of a clinical trial.Materials and methods: The experimental dentifrices comprised two compositions. One was based on the addition of 1% chloramine T (D1) and the other on the presence of 0.01% fluorosurfactant (D2). Measurements of density, pH, consistency, rheological features and abrasiveness were conducted. Sixty complete denture wearers were randomly assigned to three groups and were instructed to brush their dentures with a specific toothbrush: (1) Water (control); (2) D1; or (3) D2. Each method was used for 21 days. Denture biofilm was disclosed by a 1% neutral red solution and quantified by means of digital photos taken from the internal surface. Microbiological assessment was conducted to quantify Candida sp. and mutans streptococci. Data were evaluated by one-way anova and Tukey HSD, or Kruskal–Wallis (α = 0.05).Results: Both dentifrices decreased biofilm coverage when compared with the control group. D1 was the most efficacious treatment to reduce mutans streptococci, whereas D2 showed an intermediate outcome (anova, p < 0.040). No treatment influenced Candida albicans or non-albicans species (Kruskal–Wallis, p = 0.163 and 0.746, respectively).Conclusion: It can be concluded that brushing complete dentures with the experimental dentifrices tested could be effective for the removal of denture biofilm.

Research paper thumbnail of Effects of mechanical and chemical methods on denture biofilm accumulation

Journal of Oral Rehabilitation, 2007

summary The aim of this study was to quantify biofilm on the internal surface of upper complete ... more summary The aim of this study was to quantify biofilm on the internal surface of upper complete dentures following six possible cleansing methods. Thirty-six edentulous subjects were submitted to a time-series trial and dentures were cleansed according to six methods: (i) rinsing with water; (ii) soaking in an alkaline peroxide solution (Bonyplus); (iii) brushing with dentifrice (Dentu-Creme) and soft Johnson and Johnson’s toothbrush; (iv) combination between soaking and brushing according to methods 2 and 3; (v) brushing with dentifrice (Dentu-Creme) and soft Oral B toothbrush; (vi) combination between soaking and brushing according to methods 2 and 5. Each method was randomly used throughout 21 days. Denture biofilm was disclosed by 1% neutral red solution and quantified by means of digital photos taken from the internal surface. The six methods presented significant differences in percentage of biofilm coverage (repeated measures anova, P < 0·0001). Method 1 showed the highest values, 2 was intermediate and other results were the lowest. The most efficacious approach was 6. Biofilm tended to accumulate predominantly over specific zones of the denture base, but this pattern did not change regardless of the method employed. It can be concluded that brushing alone was more effective than the chemical method employed. The best results were obtained by a combination of methods.

Research paper thumbnail of Effect of Three Methods for Cleaning Dentures on Biofilms Formed In Vitro on Acrylic Resin

Journal of Prosthodontics, 2009

Purpose: The aim of this study was to evaluate the effect of three denture hygiene methods agains... more Purpose: The aim of this study was to evaluate the effect of three denture hygiene methods against different microbial biofilms formed on acrylic resin specimens.Materials and methods: The set (sterile stainless steel basket and specimens) was contaminated (37°C for 48 hours) by a microbial inoculum with 106 colony-forming units (CFU)/ml (standard strains: Staphylococcus aureus, Streptococcus mutans, Escherichia coli, Candida albicans, Pseudomonas aeruginosa, and Enterococcus faecalis; field strains: S. mutans, C. albicans, C. glabrata, and C. tropicalis). After inoculation, specimens were cleansed by the following methods: (1) chemical: immersion in an alkaline peroxide solution (Bonyplus tablets) for 5 minutes; (2) mechanical: brushing with a dentifrice for removable prostheses (Dentu Creme) for 20 seconds; and (3) a combination of chemical and mechanical methods. Specimens were applied onto a Petri plate with appropriate culture medium for 10 minutes. Afterward, the specimens were removed and the plates incubated at 37°C for 48 hours.Results: Chemical, mechanical, and combination methods showed no significant difference in the reduction of CFU for S. aureus, S. mutans (ATCC and field strain), and P. aeruginosa. Mechanical and combination methods were similar and more effective than the chemical method for E. faecalis, C. albicans (ATCC and field strain), and C. glabrata. The combination method was better than the chemical method for E. coli and C. tropicalis, and the mechanical method showed intermediate results.Conclusion: The three denture hygiene methods showed different effects depending on the type of microbial biofilms formed on acrylic base resin specimens.

Research paper thumbnail of New Targets in Diarrhetic Shellfish Poisoning Control

Journal of Natural Products, 2005

The toxic profile of dinoflagellates varies even among identical species, raising an interesting ... more The toxic profile of dinoflagellates varies even among identical species, raising an interesting question about the mechanism of toxin regulation and production. In consequence, it also poses a considerable problem in their control methods. In this paper, we report on the isolation and structural elucidation of several new ester derivatives of okadaic acid (OA) from artificial cultures of the genus Prorocentrum. These new compounds enlarge the range of target molecules that must be considered in the monitoring programs.

Research paper thumbnail of Identification and characterization of DTX-5c and 7-hydroxymethyl-2-methylene-octa-4,7-dienyl okadaate from Prorocentrum belizeanum cultures by LC–MS

Toxicon, 2007

The main toxins produced by the dinoflagellate Prorocentrum belizeanum, DTX5c and 7-hydroxymethyl... more The main toxins produced by the dinoflagellate Prorocentrum belizeanum, DTX5c and 7-hydroxymethyl-2methyleneocta-4,7 dienyl okadaate, were studied by liquid chromatography-coupled with ion trap mass spectrometry (LC-MS/MS). Their retention times (RTs) and fragmentation patterns were established, in particular those of DTX5c, as there is a lack of data about these water soluble OA sulphated derivatives. As an application of the LC-MS methodology, a sample of the toxic P. belizeanum culture was analysed for these metabolites. Both metabolites were detected in cells as majority compounds, whereas levels of these compounds in the culture media were undetectable. r (J.M. Franco), jjfercas@ull.es (J.J. Ferna´ndez).

Research paper thumbnail of DTX5c, a new OA sulphate ester derivative from cultures of Prorocentrum belizeanum

Toxicon, 2006

Prorocentrum belizeanum is a dinoflagellate known for its okadaic acid (OA) and dinophysitoxins (... more Prorocentrum belizeanum is a dinoflagellate known for its okadaic acid (OA) and dinophysitoxins (DTXs) production, both OA and DTX are polyether toxins of the Diarrhetic Shellfish Poisoning (DSP) group. We have recently published the isolation of a new diol-ester of okadaic acid from cultures of P. belizeanum. On this occasion we present a new sulphated water-soluble derivative, DTX-5c, isolated from this microalga, whose structure was established on the basis of its spectroscopical data. q

Research paper thumbnail of 19- epi -Okadaic Acid, a Novel Protein Phosphatase Inhibitor with Enhanced Selectivity

Organic Letters, 2007

A new protein phosphatase inhibitor, 19-epi-okadaic acid, was isolated from the marine dinoflagel... more A new protein phosphatase inhibitor, 19-epi-okadaic acid, was isolated from the marine dinoflagellate Prorocentrum belizeanum. Its structure and conformation in solution has been determined, and important differences were found when compared with the lead compound okadaic acid. The new metabolite showed nanomolar activities, and its selectivity for PP2A versus PP1 surpasses that shown by okadaic acid 10-fold, making it one of the most selective inhibitors of this class.