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1.
Braz J Microbiol ; 53(4): 1969-1977, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36224461

ABSTRACT

The present study aimed to compare the oral Candida rate between infected and uninfected children with the human immunodeficiency virus (HIV), as well as analyze the association between Candida spp. and predisposing factors of colonization, like oral biofilm index, caries experience, and laboratory markers of AIDS progression. A cross-sectional study was employed. Candida species were identified and quantified from saliva samples of 50 HIV-infected and 50 uninfected children. Biofilm index and decayed, missing, and filled teeth (dmft/DMFT) indices were assessed by oral clinical examinations. Additionally, CD4+ T lymphocyte count and viral load were obtained from medical records of the HIV-infected children. Candida species were cultured from 74% of the HIV-infected children and 46% of uninfected ones (p = 0.0076). Candida albicans and Candida parapsilosis were the most frequently isolated species in both studied groups. The isolation of Candida species was significantly higher in HIV-infected children with CD4 ≤ 15% (p = 0.0146); it had influence of mature oral biofilm and the caries index (dmft + DMFT ≥ 8) (p < 0.05) and was associated with the plasma viral load. The present data show that the HIV infection, oral biofilm index, caries experience, and laboratory markers of AIDS progression exert an influence on the prevalence of oral Candida in children.


Subject(s)
Acquired Immunodeficiency Syndrome , Dental Caries , HIV Infections , Child , Humans , HIV Infections/complications , Candida , Cross-Sectional Studies , Acquired Immunodeficiency Syndrome/complications , Dental Caries Susceptibility , Biofilms , Biomarkers , Disease Progression , Dental Caries/complications
2.
An Acad Bras Cienc ; 94(3): e20211090, 2022.
Article in English | MEDLINE | ID: mdl-36259824

ABSTRACT

The search for new therapeutic strategies for leishmaniasis treatment is essential due to the side effects of available drugs and the increasing incidence of resistance to them. Marine sponges use chemical compounds as a defense mechanism, and several of them present interesting pharmacological properties. The aim of this study was to evaluate the in vitro activity of the aqueous extract of the marine sponge Dercitus (Stoeba) latex against Leishmania amazonensis. MIC and toxicity against mammal cells were evaluated through broth microdilution assays. Transmission electron microscopy analysis was performed to assess possible effects on L. amazonensis ultrastructure. Arginase and proteolytic activities were measured by spectrometric methodologies. The extract of Dercitus (Stoeba) latex displayed antileishmanial activity and moderate toxicity against peritonial macrophages. Ultrastructural changes were observed after the growth of L. amazonensis promastigotes in the presence of the extract at 150 µg.ml-1 (IC50), mainly on acidocalcysomes. The extract was able to inhibit the activity of arginase and serine proteases. This study shows that Dercitus (Stoeba) latex aqueous extract may be a novel potential source of protozoa protease inhibitors and drugs that are less toxic to be used in the treatment of L. amazonensis infections.


Subject(s)
Antiprotozoal Agents , Leishmania mexicana , Porifera , Animals , Latex/pharmacology , Arginase/pharmacology , Brazil , Leishmania mexicana/ultrastructure , Antiprotozoal Agents/pharmacology , Protease Inhibitors/pharmacology , Serine Proteases/pharmacology , Mammals
3.
Rev Iberoam Micol ; 37(3-4): 104-106, 2020.
Article in English | MEDLINE | ID: mdl-33229297

ABSTRACT

BACKGROUND: Mortality rate of invasive Candida infections is raising mainly amongst immunocompromised patients. These infections are hard-to-treat mainly due to the increasing incidence of resistance. The overexpression of ATP-binding cassette and major facilitator superfamily transporters is the main responsible for the failure of antifungal therapies. In a Saccharomyces cerevisiae model, ß-lapachone inhibited Pdr5p, a transporter homologous to those found in Candida albicans. AIMS: To determine whether ß-lapachone reverses the resistance phenotype mediated by efflux transporters in C. albicans clinical isolates. METHODS: The antifungal activity of ß-lapachone combined with fluconazole was measured by agarose chemosensitization and microdilution assays. CaCdr2p and CaMdr1p activities were evaluated through fluorescent dyes accumulation. ATPase activity was assessed using transporter-enriched plasma membranes. RESULTS: ß-lapachone reverted antifungal resistance of S. cerevisiae and C. albicans strains overexpressing CaCdr2p and CaMdr1p transporters by inhibiting these proteins activities. CaCdr2p ATPase activity was not impaired by the compound. CONCLUSIONS: ß-lapachone is a promising drug candidate to be used as an adjuvant in the treatment of candidiasis caused by fluconazole-resistant C. albicans strains.


Subject(s)
Candida albicans , Fluconazole , Antifungal Agents/pharmacology , Drug Resistance, Fungal , Fluconazole/pharmacology , Humans , Microbial Sensitivity Tests , Naphthoquinones , Saccharomyces cerevisiae
4.
Rev. iberoam. micol ; 37(3/4): 104-106, jul.-oct. 2020. tab
Article in English | IBECS | ID: ibc-200362

ABSTRACT

BACKGROUND: Mortality rate of invasive Candida infections is raising mainly amongst immunocompromised patients. These infections are hard-to-treat mainly due to the increasing incidence of resistance. The overexpression of ATP-binding cassette and major facilitator superfamily transporters is the main responsible for the failure of antifungal therapies. In a Saccharomyces cerevisiae model, Beta-lapachone inhibited Pdr5p, a transporter homologous to those found in Candida albicans. AIMS: To determine whether Beta-lapachone reverses the resistance phenotype mediated by efflux transporters in C. albicans clinical isolates. METHODS: The antifungal activity of Beta-lapachone combined with fluconazole was measured by agarose chemosensitization and microdilution assays. CaCdr2p and CaMdr1p activities were evaluated through fluorescent dyes accumulation. ATPase activity was assessed using transporter-enriched plasma membranes. RESULTS: Beta-lapachone reverted antifungal resistance of S. cerevisiae and C. albicans strains overexpressing CaCdr2p and CaMdr1p transporters by inhibiting these proteins activities. CaCdr2p ATPase activity was not impaired by the compound. CONCLUSIONS: Beta-lapachone is a promising drug candidate to be used as an adjuvant in the treatment of candidiasis caused by fluconazole-resistant C. albicans strains


ANTECEDENTES: Las tasas de mortalidad de infecciones invasivas causadas por Candida están en aumento, principalmente entre los pacientes inmunocomprometidos. Estas infecciones son difíciles de tratar debido a la creciente incidencia de resistencia a los antifúngicos. La sobreexpresión de los transportadores dependientes de ATP y los de la superfamilia de facilitadores principales es el mayor responsable del fracaso de las terapias antimicóticas. En un modelo de Saccharomyces cerevisiae, la beta-lapachona inhibió Pdr5p, un transportador homólogo a los encontrados en Candida albicans. OBJETIVOS: Determinar si la beta-lapachona revierte el fenotipo de resistencia mediado por transportadores de eflujo en aislamientos clínicos de C. albicans. MÉTODOS: Se midió la actividad antifúngica de la beta-lapachona combinada con fluconazol mediante ensayos de quimiosensibilización con agarosa y microdilución. Las actividades CaCdr2p y CaMdr1p se evaluaron mediante la acumulación de colorantes fluorescentes, y la actividad de ATPasa se evaluó usando membranas plasmáticas enriquecidas con transportador. RESULTADOS: La beta-lapachona revirtió la resistencia antifúngica de las cepas de S. cerevisiae y C. albicans que sobreexpresaban los transportadores CaCdr2p y CaMdr1p al inhibir sus actividades. El compuesto no afectó la actividad ATPasa de CaCdr2p. CONCLUSIONES: La beta-lapachona es una candidata prometedora para ser utilizada como adyuvante en el tratamiento de la candidiasis causada por cepas de C. albicans resistentes al fluconazol


Subject(s)
Humans , Drug Synergism , Fluconazole/pharmacology , Candida albicans/drug effects , Naphthoquinones/pharmacology , Antifungal Agents/pharmacology , Microbial Sensitivity Tests , Phenotype
5.
Int J Paediatr Dent ; 2018 Jul 04.
Article in English | MEDLINE | ID: mdl-29974548

ABSTRACT

BACKGROUND: Fungal infections are a serious problem among haemodialysis patients. AIM: The aims of this study were to estimate the frequency of oral Candida species among children and adolescents undergoing haemodialysis (HD), to identify the isolated species, and to study the relationship between haemodialysis duration, amounts of colony-forming units, and salivary pH. DESIGN: A matched sample of 52 patients undergoing HD and 52 healthy individuals were selected. The samples were obtained from the dorsum of the tongue, and the colonies were identified through a substrate assimilation test. Stimulated whole saliva was collected from each patient for evaluation of salivary pH. RESULTS: The frequency of oral Candida species was 34.6% (18/52) and 46.20% (24/52) in the HD and control groups (P = 0.23), respectively. Candida parapsilosis complex was the most frequently isolated fungi species in the HD group (P = 0.03). A HD therapy duration of more than 1 year was statistically correlated with a higher number of colony-forming units (P = 0.03) but was not statistically related to salivary pH. CONCLUSIONS: Candida parapsilosis complex was the most frequently isolated fungal species in the young HD patients, and the duration therapy was associated with higher oral colonization.

6.
J Appl Oral Sci ; 25(1): 53-60, 2017.
Article in English | MEDLINE | ID: mdl-28198976

ABSTRACT

OBJECTIVES: This study analyzed the capacity of Candida spp. from dental biofilm of HIV infected (HIV+) children to demineralize primary molar enamel in vitro by Transversal Microhardness (TMH), Polarized Light Microscopy (PLM) and the quantity of calcium ions (Ca2+) released from the enamel. MATERIAL AND METHODS: Candida spp. samples were isolated from the supragingival biofilm of HIV+ children. A hundred and forty (140) enamel blocks were randomly assigned to six groups: biofilm formed by C. albicans (Group 1); mixed biofilm formed by C. albicans and C. tropicalis (Group 2); mixed biofilm formed by C. albicans and C. parapsilosis (Group 3); mixed biofilm formed by C. albicans, C. parapsilosis and C. glabrata (Group 4); biofilm formed by C. albicans ATCC (Group 5) and medium without Candida (Group 6). Enamel blocks from each group were removed on days 3, 5, 8 and 15 after biofilm formation to evaluate the TMH and images of enamel were analyzed by PLM. The quantity of Ca2+ released, from Groups 1 and 6, was determined using an Atomic Absorption Spectrophotometer. The SPSS program was used for statistical analysis and the significance level was 5%. RESULTS: TMH showed a gradual reduction in enamel hardness (p<0.05) from the 1st to 15th day, but mainly five days after biofilm formation in all groups. The PLM showed superficial lesions indicating an increase in porosity. C. albicans caused the release of Ca2+ into suspension during biofilm formation. CONCLUSION: Candida species from dental biofilm of HIV+ children can cause demineralization of primary enamel in vitro.


Subject(s)
Candida/isolation & purification , Candida/pathogenicity , Dental Caries/microbiology , Dental Enamel/microbiology , HIV Infections/microbiology , Analysis of Variance , Biofilms/growth & development , Calcium/metabolism , Candida/growth & development , Candida/virology , Child , Child, Preschool , Dental Caries/virology , Dental Enamel/virology , Dental Plaque/microbiology , Dental Plaque/virology , Female , HIV Infections/complications , Hardness Tests , Humans , In Vitro Techniques , Male , Microscopy, Polarization , Reference Values , Spectrophotometry, Atomic , Time Factors , Tooth, Deciduous/microbiology , Tooth, Deciduous/virology , Virulence
7.
J. appl. oral sci ; 25(1): 53-60, Jan.-Feb. 2017. tab, graf
Article in English | LILACS, BBO - Dentistry | ID: biblio-841164

ABSTRACT

Abstract Objectives This study analyzed the capacity of Candida spp. from dental biofilm of HIV infected (HIV+) children to demineralize primary molar enamel in vitro by Transversal Microhardness (TMH), Polarized Light Microscopy (PLM) and the quantity of calcium ions (Ca2+) released from the enamel. Material and Methods Candida spp. samples were isolated from the supragingival biofilm of HIV+ children. A hundred and forty (140) enamel blocks were randomly assigned to six groups: biofilm formed by C. albicans (Group 1); mixed biofilm formed by C. albicans and C. tropicalis (Group 2); mixed biofilm formed by C. albicans and C. parapsilosis (Group 3); mixed biofilm formed by C. albicans, C. parapsilosis and C. glabrata (Group 4); biofilm formed by C. albicans ATCC (Group 5) and medium without Candida (Group 6). Enamel blocks from each group were removed on days 3, 5, 8 and 15 after biofilm formation to evaluate the TMH and images of enamel were analyzed by PLM. The quantity of Ca2+ released, from Groups 1 and 6, was determined using an Atomic Absorption Spectrophotometer. The SPSS program was used for statistical analysis and the significance level was 5%. Results TMH showed a gradual reduction in enamel hardness (p<0.05) from the 1st to 15th day, but mainly five days after biofilm formation in all groups. The PLM showed superficial lesions indicating an increase in porosity. C. albicans caused the release of Ca2+ into suspension during biofilm formation. Conclusion Candida species from dental biofilm of HIV+ children can cause demineralization of primary enamel in vitro.


Subject(s)
Humans , Male , Female , Child, Preschool , Child , Candida/isolation & purification , Candida/pathogenicity , HIV Infections/microbiology , Dental Caries/microbiology , Dental Enamel/microbiology , Reference Values , Spectrophotometry, Atomic , Time Factors , Tooth, Deciduous/microbiology , Tooth, Deciduous/virology , Virulence , In Vitro Techniques , Candida/growth & development , Candida/virology , HIV Infections/complications , Calcium/metabolism , Analysis of Variance , Biofilms/growth & development , Dental Caries/virology , Dental Enamel/virology , Dental Plaque/microbiology , Dental Plaque/virology , Hardness Tests , Microscopy, Polarization
8.
Parasitol Int ; 66(2): 47-55, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27888011

ABSTRACT

Leishmania (Leishmania) infantum chagasi is one of the agents that cause visceral leishmaniasis. This disease occurs more frequently in third world countries, such as Brazil. The treatment is arduous, and is dependent on just a few drugs like the antimonial derivatives and amphotericin B. Moreover, these drugs are not only expensive, but they can also cause severe side effects and require long-term treatment. Therefore, it is very important to find new compounds that are effective against leishmaniasis. In the present work we evaluated a new group of synthetic amides against the promastigote and amastigote forms of L. infantum chagasi. The results showed that one of these amides in particular, presented very effective activity against the promastigotes and amastigotes of L. infantum chagasi at low concentrations and it also presented low toxicity for mammal cells, which makes this synthetic amide a promising drug for combating leishmaniasis.


Subject(s)
Antiprotozoal Agents/pharmacology , Leishmania infantum/drug effects , Phenethylamines/pharmacology , Animals , Antiprotozoal Agents/chemical synthesis , Antiprotozoal Agents/chemistry , Brazil , Cell Line , Drug Discovery , Leishmania/drug effects , Leishmania/ultrastructure , Leishmania infantum/growth & development , Leishmania infantum/physiology , Leishmania infantum/ultrastructure , Life Cycle Stages/drug effects , Macrophages, Peritoneal/drug effects , Mice , Phenethylamines/chemical synthesis , Phenethylamines/chemistry
9.
J Dent Child (Chic) ; 83(3): 139-145, 2016 Sep 15.
Article in English | MEDLINE | ID: mdl-28327264

ABSTRACT

PURPOSE: The purposes of this study were to: (1) quantify and identify Candida species (spp.) in the dental plaque of children infected with the human immunodeficiency virus (HIV) and compare with noninfected children; and (2) determine the association of Candida spp. with the presence of caries. METHODS: Seventy HIV-infected and 55 non-HIV-infected three- to 12-year-old children were examined to determine caries prevalence. After a visual inspection, supragingival plaque was collected from the cervical region using standard dental curettes. The material was transferred to microtubes and submitted for analysis to identify and quantify the presence of Candida spp. RESULTS: Candida spp. were more prevalent in the HIV-infected group (72.9 percent) than in the control group (20 percent), and the most prevalent specie was Candida albicans. Caries was found in 72.9 percent of the HIV-infected group and in 58.2 percent of the control group, but a significant difference was only found in the presence of active white spot lesions between the groups. CONCLUSIONS: The dental plaque of HIV-infected children was colonized by Candida species to a much greater extent than that of non-HIV-infected children, and this colonization was significantly associated with the prevalence of early carious lesions in enamel.


Subject(s)
Candida/isolation & purification , Dental Caries/epidemiology , Dental Caries/microbiology , Dental Plaque/microbiology , HIV Infections/complications , Biofilms/growth & development , Brazil , Candida/classification , Candida/growth & development , Candida albicans/isolation & purification , Child , Child, Preschool , Dental Caries/complications , Dental Enamel/microbiology , Disease Susceptibility , Female , Humans , Male , Prevalence , Statistics, Nonparametric
10.
Clin Oral Investig ; 19(8): 1973-80, 2015 Nov.
Article in English | MEDLINE | ID: mdl-25786587

ABSTRACT

OBJECTIVES: The aims of this study were to investigate the caries experience, periodontal status, oral hygiene habits, and salivary parameters of children and adolescents undergoing hemodialysis (HD) and to compare them with their healthy counterparts. METHODS: Fifty-two HD patients were matched for age, sex, ethnicity, and social class with 52 healthy subjects for analysis of the number of decayed, missing and filled teeth, plaque and gingival index, dental calculus accumulation, measurements of pocket depth, clinical attachment level, gingival recession, and bleeding on probing. Stimulated saliva samples were collected to assess salivary flow rate, pH and buffer capacity, and salivary concentrations of calcium, phosphate, and urea by colorimetric method. RESULTS: HD patients had lower dental caries (p = 0.004), greater plaque and calculus accumulation (p = 0.001), and reported flossing less often than the controls (p = 0.013). Regarding salivary analysis, HD patients showed significantly higher values of pH, buffer capacity, and salivary urea concentration when compared to the controls (p = 0.001). CONCLUSION: HD patients had lower caries experience, higher accumulation of dental plaque, and calculus deposition than their healthy counterparts, probably due to the differences found in their salivary biochemical parameters. CLINICAL SIGNIFICANCE: A significant number of children and adolescents undergoing hemodialysis are candidates for kidney transplantation and should receive complete pre-transplant dental exams and dental treatment. Our results open the way for the development of an individualized dental protocol for these patients with preventive measures and treatment of the poor oral health in HD patients.


Subject(s)
Dental Caries , Oral Hygiene , Renal Dialysis , Saliva/metabolism , Salivary Calculi , Adolescent , Child , Dental Caries/epidemiology , Dental Caries/metabolism , Female , Humans , Male , Salivary Calculi/epidemiology , Salivary Calculi/metabolism
11.
Arch Oral Biol ; 59(9): 928-37, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24907522

ABSTRACT

OBJECTIVES: The aim of this study was to evaluate the effect of SLPI on the growth and biological processes of Candida albicans. METHODS: Two C. albicans strains were used in this study, a clinical isolate resistant to fluconazole (PRI) and a reference strain ATCC 24433. The minimal inhibitory concentration (MIC) was determined according to the CLSI methodology. The influence of SLPI on secreted serine proteinase activities (SSP) was measured by the cleavage of specific substrate, and surface hydrophobicity was determined by the aqueous-hydrocarbon biphasic separation method. Flow cytometry was performed to investigate receptors for SLPI and variations in the cell wall mannoprotein expression. Interaction between yeast and epithelium was assessed using the MA-104 cells lineage. Ultrastructure was analyzed by transmission electron microscopy (TEM). RESULTS: MIC values were calculated as 18 and 18.9µM for the PRI and ATCC 24433, respectively. SSP activity was reduced by 48.8% by 18µM of SLPI and cell surface hydrophobicity increased by 11.1%. Flow cytometry suggest the existence of SLPI binding sites on the surface of the yeast. Results showed a reduction in the expression of mannoproteins in 20.8% by the cells treated with 80µM of SLPI, and 18µM reduced the adhesion of yeasts to mammalian cells in 60.1%. TEM revealed ultrastructural changes in cells treated with 80µM of SLPI, such as the presence of membrane-like structures within the cytoplasm. CONCLUSIONS: SLPI exerts a significant influence on C. albicans viability and biological processes. Considering its constitutive and physiologic features, SLPI may become a promising tool for the development of new methodologies for the treatment and control of candidiasis.


Subject(s)
Antifungal Agents/pharmacology , Candida albicans/drug effects , Secretory Leukocyte Peptidase Inhibitor/pharmacology , Biological Phenomena/drug effects , Candida albicans/ultrastructure , Cell Adhesion/drug effects , Drug Resistance, Fungal , Flow Cytometry , Fluconazole/pharmacology , Humans , In Vitro Techniques , Membrane Glycoproteins/metabolism , Microbial Sensitivity Tests , Microscopy, Electron , Nystatin/pharmacology
12.
Arch Oral Biol ; 59(8): 775-82, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24837476

ABSTRACT

OBJECTIVES: This study aimed to evaluate the concentration of lactoferrin in the saliva of HIV infected and healthy children and analyze the associations between lactoferrin levels, Candida sp. colonization, oral manifestations and medical data. Also, the antifungal ability of lactoferrin to inhibit the growth of Candida albicans isolated from saliva of these children was investigated in vitro. SUBJECTS AND METHODS: Saliva was collected from 70 HIV-infected and 50 healthy children, followed by oral manifestation assessments. The salivary lactoferrin was quantified using an ELISA Kit. The salivary samples were cultured and the Candida spp. colonies counted and then identified by sugar assimilation and fermentation. The antifungal activity of lactoferrin was analyzed in vitro with 10 isolates of C. albicans from each group. RESULTS: The HIV infected children (mean age 9.8 ± 2.8) had higher lactoferrin levels (median 6.13 µg/ml (3.58-7.89)) and were colonized three times more by Candida sp. than the control group (mean age 9.4 ± 2.4) (median 5.74 µg/ml (3.12-6.86)) (p=0.003). Statistical associations were found considering the salivary lactoferrin levels and Candida sp. and oral manifestations between the groups. No associations between lactoferrin concentrations and oral manifestations, immunosuppression, presence of AIDS and use of HAART were observed in the HIV group. The percentage of dead C. albicans due to lactoferrin was inversely proportional to C. albicans cell density for both groups (p<0.001). CONCLUSIONS: HIV-infected children have higher concentrations of lactoferrin and it was associated with Candida sp. colonization but no association with medical data was found. Also, both groups showed similar lactoferrin antifungal activity.


Subject(s)
AIDS-Related Opportunistic Infections/drug therapy , AIDS-Related Opportunistic Infections/microbiology , Antifungal Agents/pharmacology , Candida albicans/drug effects , Lactoferrin/metabolism , Lactoferrin/pharmacology , Saliva/metabolism , Saliva/microbiology , Adolescent , Antiretroviral Therapy, Highly Active , Brazil , Candidiasis, Oral/drug therapy , Candidiasis, Oral/microbiology , Case-Control Studies , Child , Child, Preschool , Cross-Sectional Studies , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male
13.
Pediatr Nephrol ; 29(5): 771-8, 2014 May.
Article in English | MEDLINE | ID: mdl-23595424

ABSTRACT

BACKGROUND: The aim of this systematic review was to determine whether there is any evidence in the literature referring to a lower prevalence of dental caries in children and adolescents with chronic kidney disease (CKD) compared to healthy individuals. METHODS: A search of the PubMed Medline, Ovid Medline and Cochrane Library databases was performed using the MeSH terms "dental caries" and "chronic renal failure". To be eligible for entry in our study, controlled observational studies had to present a decayed, missing and filled index for primary teeth (dmft) and/or for permanent teeth (DMFT) in children and adolescents with CKD. RESULTS: After evaluation of title, keywords and abstracts of the articles selected, six articles met the inclusion criteria. Three of these six articles included studies which showed susceptibility to bias and possible confounding factors. A subsequent assessment of the six studies revealed that the mean caries indices in both primary (dmf) and permanent (DMF) teeth were lower in the children and adolescents with CKD compared with healthy individuals. CONCLUSION: Data in the literature weakly support a lower prevalence of caries in children and adolescents with CKD than in their healthy counterparts. There is still a lack of well-designed studies that provide better scientific evidence in support of this conclusion.


Subject(s)
Dental Caries/epidemiology , Renal Insufficiency, Chronic/complications , Renal Insufficiency, Chronic/epidemiology , Adolescent , Child , Humans
14.
Article in English | MEDLINE | ID: mdl-23380483

ABSTRACT

OBJECTIVE: The aim of this study was to analyze the effect of C. albicans on enamel microhardness in vitro. STUDY DESIGN: Candida albicans was isolated from the oral mucosa (M) and dentin carious lesion (D) of an HIV+ child. Three groups of 12 enamel blocks each were placed in Petri plates (yeast carbon base agar/1% bovine serum albumin): G1, exposed to biofilm formed by C. albicans from M; G2, exposed to biofilm formed by C. albicans from D; G3, no biofilm. Three enamel blocks from each group were removed on days 3, 5, 8, and 10 after biofilm formation to measure the cross-sectional Knoop microhardness (CSMH) of the enamel areas, exposed and not exposed to biofilm. RESULTS: CSMH decreased in G1 and G2: in G1 on day 5, and in G2 on day 3 (analysis of variance: P < .05; Mann-Whitney test: P < .05), with a similar mean percentage reduction for both groups. CONCLUSIONS: Candida albicans can reduce enamel microhardness in vitro.


Subject(s)
Biofilms , Candida albicans/physiology , Dental Enamel/microbiology , HIV Seropositivity/microbiology , Mouth/microbiology , Child , Dental Caries/microbiology , Dental Enamel/ultrastructure , Dentin/microbiology , Hardness , Humans , Microbial Viability , Mouth Mucosa/microbiology , Mycology/methods , Time Factors , Tooth Demineralization/microbiology
15.
Front Microbiol ; 3: 283, 2012.
Article in English | MEDLINE | ID: mdl-22888328

ABSTRACT

Leishmaniasis and trypanosomiasis are two neglected and potentially lethal diseases that affect mostly the poor and marginal populations of developing countries around the world and consequently have an important impact on public health. Clinical manifestations such as cutaneous, mucocutaneous, and visceral disorders are the most frequent forms of leishmaniasis, a group of diseases caused by several Leishmania spp. American trypanosomiasis, or Chagas disease, is caused by Trypanosoma cruzi, a parasite that causes progressive damage to different organs, particularly the heart, esophagus, and lower intestine. African trypanosomiasis, or sleeping sickness, is caused by Trypanosoma brucei and is characterized by first presenting as an acute form that affects blood clotting and then becoming a chronic meningoencephalitis. The limited number, low efficacy, and side effects of conventional anti-leishmania and anti-trypanosomal drugs and the resistance developed by parasites are the major factors responsible for the growth in mortality rates. Recent research focused on plants has shown an ingenious way to obtain a solid and potentially rich source of drug candidates against various infectious diseases. Bioactive phytocompounds present in the crude extracts and essential oils of medicinal plants are components of an important strategy linked to the discovery of new medicines. These compounds have proven to be a good source of therapeutic agents for the treatment of leishmaniasis and trypanosomiasis. This work highlights some chemotherapeutic agents while emphasizing the importance of plants as a source of new and powerful drugs against these widespread diseases.

16.
Article in English | MEDLINE | ID: mdl-22669144

ABSTRACT

OBJECTIVE: The aim of this study was to compare type I collagen degradation by Candida albicans isolated from oral mucosa (M) and cavitated active dentinal caries (CAD) of HIV-infected children. STUDY DESIGN: To verify the proteolytic activity, the specimens were cultivated in brain-heart infusion medium and the supernatants were incubated in the presence or absence of type I collagen at 37°C for 12 hours and analyzed using 10% sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Intensity of the bands on the gels was assessed by densitometric analysis using a scanner and images analyzed with software from Kodak Digital Science EDAS 120. RESULTS: Supernatants of all the C. albicans degraded type I collagen: that from M, on average, by 38.3% (SD 21.67) and that from CAD by 54% (SD 25.94; Wilcoxon test: P < .05). Predisposing factors had no association with the percentage of type I collagen degradation (Mann-Whitney test: P > .05). CONCLUSIONS: Candida albicans from different sites of the oral cavity of HIV-infected children has proteolytic activity for type I collagen.


Subject(s)
Candida albicans/enzymology , Collagen Type I/metabolism , Dental Caries/microbiology , HIV Infections/complications , Mouth Mucosa/microbiology , Child , Child, Preschool , Dental Caries/complications , Dentin/microbiology , Female , Humans , Male , Proteolysis , Statistics, Nonparametric
17.
Bioelectromagnetics ; 33(4): 334-45, 2012 May.
Article in English | MEDLINE | ID: mdl-22012884

ABSTRACT

The literature shows that the effects of direct electric currents on biological material are numerous, including bactericidal, fungicidal, parasiticidal, and anti-tumoral, among others. Non-pathogenic trypanosomatids, such as Herpetomonas samuelpessoai, have emerged as important models for the study of basic biological processes performed by a eukaryotic cell. The present study reports a dose-dependent anti-protozoan effect of direct electric treatment with both cathodic and anodic current flows on H. samuelpessoai cells. The damaging effects can be attributable to the electrolysis products generated during electric stimulation. The pH of the cell suspension was progressively augmented from 7.4 to 10.5 after the cathodic treatment. In contrast, the anodic treatment caused a pH decrease varying from 7.4 to 6.5. Transmission electron microscopy analyses revealed profound alterations in vital cellular structures (e.g., mitochondrion, kinetoplast, flagellum, flagellar pocket, nucleus, and plasma membrane) after exposure to both cathodic and anodic current flows. Specifically, cathodic current flow treatment induced the appearance of autophagic-like structures on parasite cells, while those submitted to an anodic current flow presented marked disorganization of plasma membrane and necrotic appearance. However, parasites treated in the intermediary chamber (without contact with the electrodes) did not present significant changes in viability or morphology, and no pH variation was detected in this system. The use of H. samuelpessoai as a biological model and the direct electric current experimental approach used in our study provide important information for understanding the mechanisms involved in the cytotoxic effects of this physical agent.


Subject(s)
Electric Conductivity/adverse effects , Trypanosomatina/ultrastructure , Cell Survival , Trypanosomatina/cytology
18.
Int. j. high dilution res ; 10(36): 152-154, september 30, 2011.
Article in English | LILACS-Express | HomeoIndex Homeopathy | ID: hom-10715

ABSTRACT

Oral candidiasis is an opportunist fungal infection in humans, mainly caused by Candida albicans. It occurs when the host presents an imbalance in the immune system and Candida spp., normally found in human flora, become able to develop the infection [1]. This disease is very common in HIV patients, and in all individuals that present immunossupression, such as patients treated with chemotherapy. Considering this scenario, the development of new medicines to treat oral candidiasis is mandatory.These results showed that the biotherapic did not present any citotoxicity, but was able to modify the morphological aspects of Ma-104 cells. Additionally, the interaction between host cells and ethilogic agent is directly influenced by biotherapic treatment, suggesting a promising antifungal potential of this medicine.(AU)


Subject(s)
Candida albicans , Biotherapics
19.
Pediatr Dent ; 33(2): 153-7, 2011.
Article in English | MEDLINE | ID: mdl-21703065

ABSTRACT

PURPOSE: The purpose of this study was to evaluate chlorhexidine to control gingivitis and Candida species (spp.) in children infected with the human immunodeficiency virus (HIV) and their acceptance of the therapy. METHODS: Twenty-six HIV+ children were selected, and oral exam-established biofilm, gingival indexes, and stimulated saliva were collected for Candida ssp. identification. The children brushed their teeth for 21 days with chlorhexidine gel (0.2%). Salivary samples, biofilm, and gingival indexes were collected after 21-days and again 35 days after ceasing gel use. The children answered a questionnaire about the therapy. RESULTS: All children tested positive for Candida and gingivitis. After 21 days, Candida counts and gingivitis decreased in 25 and 26 children, respectively. Mean reduction was approximately 68% for Candida spp. and 74% for gingivitis. Thirty-five days after discontinuing gel use, gingivitis and Candida spp. increased in 13 and 16 patients, respectively. Considering the Candida spp., the heavy growth was lower in the first re-evaluation. Candida albicans was the most frequent species. Approximately 85% did not experience inconvenience with the gel, and approximately 48% thought it was good for tooth-brushing. CONCLUSION: Chlorhexidine therapy may be an option to treat and pre- vent gingivitis and reduce yeast counts in children infected with HIV.


Subject(s)
Anti-Infective Agents, Local/therapeutic use , Candida/drug effects , Chlorhexidine/therapeutic use , Gingivitis/prevention & control , HIV Infections/complications , Saliva/microbiology , Adolescent , Anti-Infective Agents, Local/administration & dosage , Antiretroviral Therapy, Highly Active , Biofilms , Candida/classification , Candida albicans/drug effects , Candida tropicalis/drug effects , Child , Chlorhexidine/administration & dosage , Cohort Studies , Colony Count, Microbial , Female , Follow-Up Studies , Gels , HIV Infections/drug therapy , HIV Seropositivity/complications , HIV Seropositivity/drug therapy , Humans , Male , Patient Satisfaction , Periodontal Index , Pilot Projects , Toothbrushing , Toothpastes/therapeutic use , Treatment Outcome
20.
Braz Oral Res ; 24(4): 406-12, 2010.
Article in English | MEDLINE | ID: mdl-21180960

ABSTRACT

The present study evaluated the antimicrobial activity of three root canal irrigants against Enterococcus faecalis, Candida albicans, and Staphylococcus aureus. These microorganisms were incubated in the presence of citric acid (6 and 10%), EDTA (17%), and NaOCl (0.5, 1.0, 2.5, and 5.25%). Agar diffusion tests were performed and redox indicator resazurin was used to evaluate the inhibitory effect of the irrigants on the metabolic activity of these microorganisms. The mean diameters of the inhibition zones for the C. albicans cultures were 11.6 mm (17% EDTA), 5.5 mm (0.5% NaOCl), 12.9 mm (1% NaOCl), 22.1 mm (2.5% NaOCl), and 28.5 mm (5.25% NaOCl). The mean diameters of the inhibition zones for E. faecalis were 2.8 mm (1% NaOCl), 5.4 mm (2.5% NaOCl), and 8.3 mm (5.25% NaOCl). For S. aureus, the mean values were 8.0 mm (17% EDTA), 3.0 mm (1% NaOCl), 8.8 mm (2.5% NaOCl), and 10.0 mm (5.25% NaOCl). Most of the irrigant solutions presented effective antimicrobial activity against C. albicans. A high inhibitory effect on the metabolic activity of E. faecalis was detected when the microorganisms were incubated with 17% EDTA. The same result was reached when S. aureus was incubated in the presence of > 2.5% NaOCl. Altogether, these results indicate that 2.5% and 5.25% NaOCl are microbicides against S. aureus while 0.5% and 1% NaOCl are only microbiostatic against the tested bacteria. The 6% and 10% citric acid as well as 17% EDTA did not affect the viability of any of the assayed microorganisms.


Subject(s)
Candida albicans/drug effects , Enterococcus faecalis/drug effects , Root Canal Irrigants/pharmacology , Staphylococcus aureus/drug effects , Analysis of Variance , Anti-Infective Agents, Local/pharmacology , Citric Acid/pharmacology , Edetic Acid/pharmacology , Microbial Sensitivity Tests , Sodium Hypochlorite/pharmacology , Time Factors
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