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1.
Comp Immunol Microbiol Infect Dis ; 93: 101940, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36603241

RESUMO

Genotyping of Staphylococcus aureus isolated from mastitis has become a fundamental tool to understand its complex epidemiology and to evaluate spillover events. The aim of this study was to describe the frequency of genotypes of the S. aureus strains isolated from intramammary infections by spa typing technique, and to evaluate the association between genotypes and the ability to form biofilm under in vitro conditions. Sixty-six strains of S. aureus recovered from bovines intramammary infections on 56 dairy herds located in 14 municipalities of the department of Antioquia were characterized. The majority of strains (65/66) were isolated from milk samples collected from dairy cows with subclinical intramammary infections. Nineteen different spa types were found in this study, t521 (19.70%), t267 (15.15%), and t605 (12.12%) being the most frequent. The strains from the t605 spa type showed the highest biofilm production. The high frequency of spa types with zoonotic potential found in this study, identified cattle as an important reservoir of theses clones for people in close proximity, such as milkers and consumers of unpasteurized dairy products.


Assuntos
Doenças dos Bovinos , Mastite Bovina , Infecções Estafilocócicas , Feminino , Bovinos , Animais , Staphylococcus aureus/genética , Leite , Mastite Bovina/epidemiologia , Variação Genética , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/veterinária
2.
MethodsX ; 10: 101973, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36590319

RESUMO

This work details the production of solid composite particles by the aerosol-assisted chemical vapor deposition method. With this method it is feasible to produce at low temperature (450 °C) the tetragonal phase of zirconium oxide stabilizing it with yttrium oxide (YSZ) and cubic iron oxide (Fe3O4) at the same time. The particles have a solid morphology in which both metal oxides coexist without mixing. The average size of the obtained particles is 329 ± 81 nm, moreover, each particle is formed by thousands of crystallites of size 2 ± 0.5 nm. The formation of solid structures is due to the amount of Zr and Y found in each particle. These particles can be applied as reinforcements of metallic structures. •A simple and low-cost method for producing composite particles to be applied as reinforcing agents for metal structures.•The particles are formed by two phases of tetragonal yttria-stabilized zirconia (t-YSZ) and cubic Fe3O4, which was synthesized following a one-step process via the aerosol-assisted chemical vapor deposition method (AACVD).•The tetragonal phase of ZrO2 is obtained at 450 °C stabilizing it with ∼3.8% of yttrium oxide.

3.
Neurologia (Engl Ed) ; 36(9): 681-691, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34752346

RESUMO

INTRODUCTION: Alzheimer disease risk polymorphisms have been studied in patients with dementia, but have not yet been explored in mild cognitive impairment (MCI) in our population; nor have they been addressed in relation to cognitive variables, which can be predictive biomarkers of disease. OBJECTIVE: To evaluate cognitive performance and presence of polymorphisms of the genes SORL1(rs11218304), PVRL2(rs6859), CR1(rs6656401), TOMM40(rs2075650), APOE (isoforms ε2, ε3, ε4), PICALM(rs3851179), GWAS_14q(rs11622883), BIN1(rs744373), and CLU(rs227959 and rs11136000) in patients with MCI and healthy individuals. METHODOLOGY: We performed a cross-sectional, exploratory, descriptive study of a prospective cohort of participants selected by non-probabilistic sampling, evaluated with neurological, neuropsychological, and genetic testing, and classified as cognitively healthy individuals and patients with MCI. Cognition was evaluated with the Neuronorma battery and analysed in relation to the polymorphic variants by means of measures of central tendency, confidence intervals, and nonparametric statistics. RESULTS: We found differences in performance in language and memory tasks between carriers and non-carriers of BIN1, CLU, and CR1 variants and a trend towards poor cognitive performance for PICALM, GWAS_14q, SORL1, and PVRL2 variants; the APOE and TOMM40 variants were not associated with poor cognitive performance. DISCUSSION: Differences in cognitive performance associated with these polymorphic variants may suggest that the mechanisms regulating these genes could have an effect on cognition in the absence of dementia; however, this study was exploratory and hypotheses based on these results must be explored in larger samples.


Assuntos
Disfunção Cognitiva , Proteínas Monoméricas de Montagem de Clatrina , Proteínas Adaptadoras de Transdução de Sinal , Apolipoproteínas E/genética , Clusterina/genética , Cognição , Disfunção Cognitiva/genética , Estudos Transversais , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Proteínas Relacionadas a Receptor de LDL , Proteínas de Membrana Transportadoras/genética , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial , Proteínas Monoméricas de Montagem de Clatrina/genética , Proteínas Nucleares , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Receptores de Complemento 3b/genética , Proteínas Supressoras de Tumor
4.
Heliyon ; 5(10): e02535, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31667388

RESUMO

The ability of Staphylococcus aureus to form biofilms is an important virulence factor because this has been associated with persistent bovine intramammary infections. Different mechanisms of biofilm formation have been described in S. aureus; however, the process has been found to be mainly driven by the ica and bap genes. The presence of the ica and bap genes, as well as the biofilm formation in vitro were evaluated in 229 S. aureus strains isolated from bovine milk collected from different regions of Department of Antioquia, Colombia. Three different genotypes grouped into three separate clusters were identified from in vitro assays. Genotype 1 (ica positive and bap negative) was the most prevalent (78.17%), followed by genotype 2 (ica and bap positive) (12.66%) and genotype 0 (ica and bap negative) (9.17%). Biofilm formation was observed in 81.26% of the strains from which 100% of genotype 2 isolates showed biofilm formation. The biofilms formed by genotype 2 isolates were also found to have the highest optical density (>2.4). These results showed that most of the S. aureus strains were capable of biofilm formation, suggesting the virulence potential particularly in bap-positive strains.

5.
Neurologia (Engl Ed) ; 2018 Nov 30.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30503753

RESUMO

INTRODUCTION: Alzheimer disease risk polymorphisms have been studied in patients with dementia, but have not yet been explored in mild cognitive impairment (MCI) in our population; nor have they been addressed in relation to cognitive variables, which can be predictive biomarkers of disease. OBJECTIVE: To evaluate cognitive performance and presence of polymorphisms of the genes SORL1(rs11218304), PVRL2(rs6859), CR1(rs6656401), TOMM40(rs2075650), APOE (isoforms ɛ2, ɛ3, ɛ4), PICALM(rs3851179), GWAS_14q(rs11622883), BIN1(rs744373), and CLU (rs227959 and rs11136000) in patients with MCI and healthy individuals. METHODOLOGY: We performed a cross-sectional, exploratory, descriptive study of a prospective cohort of participants selected by non-probabilistic sampling, evaluated with neurological, neuropsychological, and genetic testing, and classified as cognitively healthy individuals and patients with MCI. Cognition was evaluated with the Neuronorma battery and analysed in relation to the polymorphic variants by means of measures of central tendency, confidence intervals, and nonparametric statistics. RESULTS: We found differences in performance in language and memory tasks between carriers and non-carriers of BIN1, CLU, and CR1 variants and a trend toward poor cognitive performance for PICALM, GWAS_14q, SORL1, and PVRL2 variants; the APOE and TOMM40 variants were not associated with poor cognitive performance. DISCUSSION: Differences in cognitive performance associated with these polymorphic variants may suggest that the mechanisms regulating these genes could have an effect on cognition in the absence of dementia; however, this study was exploratory and hypotheses based on these results must be explored in larger samples.

6.
Hematology ; 22(5): 286-291, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27960630

RESUMO

OBJECTIVES: Acute lymphoblastic leukemia (ALL) is a clonal disease that accounts for 20% of acute leukemias in adults. A high percentage of adult patients (ranging from 70 to 80%) reach complete remission; however, the 5-year survival rate is only 20-40%. One of the main obstacles to treatment success is the drug resistance of leukemic cells. Therefore, our research group analyzed the ABCB1 and ABCG2 gene expression levels in 61 patients diagnosed with ALL and assessed whether the levels affected the clinical parameters and 40-month survival rate. METHODS: The ABCB1 and ABCG2 gene expression levels were analyzed using real-time polymerase chain reaction in 61 patients diagnosed with ALL and 99 healthy donors as controls. The association between ABCB1 and ABCG2 gene expression levels and clinical variables was determined using the Chi-square test and Fisher's exact test. Overall survival (OS) was determined using the Kaplan-Meier method. RESULTS: The results showed high ABCB1 and ABCG2 gene levels, which were 4.5 and 2.3 times the levels of healthy donors, respectively. A total of 52% of the study patients expressed high ABCB1 levels and were significantly associated with the high-risk patient group and a decreased 40-month survival rate of 78%. Only 49% of the patients expressed high ABCG2 gene levels. No association was found between the clinical parameters and the ABCG2 gene expression levels. CONCLUSIONS: Early detection of ABCB1 gene expression levels could be important for the diagnosis and monitoring of ALL patients.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/biossíntese , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/biossíntese , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Subfamília B de Transportador de Cassetes de Ligação de ATP/biossíntese , Adolescente , Adulto , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida
8.
Br J Nutr ; 113(2): 350-65, 2015 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25572038

RESUMO

Common pharmacological treatments of mood disorders aim to modulate serotonergic neurotransmission and enhance serotonin levels in the brain. Brain serotonin levels are dependent on the availability of its food-derived precursor essential amino acid tryptophan (Trp). We tested the hypothesis that delivery of Trp via food may serve as an alternative treatment, and examined the effects of a Trp-rich, bioavailable dietary supplement from egg protein hydrolysate on cognitive and emotional functions, mood state, and sleep quality. In a randomised, placebo-controlled, parallel trial, fifty-nine mentally and physically healthy women aged 45-65 years received placebo (n 30) or the supplement (n 29) (both as 0.5 g twice per d) for 19 d. Emotional processing was significantly changed by supplementation, exhibiting a shift in bias away from negative stimuli. The results for the Affective Go/No-Go Task exhibited a slowing of responses to negative words, suggesting reduced attention to negative emotional stimuli. The results for the Facial Emotional Expression Rating Task also supported a shift away from attention to negative emotions and a bias towards happiness. An increase in arousal-like symptoms, labelled 'high energy', shorter reaction times and a slight benefit to sustained attention were observed in the treated subjects. Finally, when the supplement was taken 60-90 min before bedtime, a feeling of happiness before going to bed was consistently reported. In summary, daily consumption of a low-dose supplement containing bioavailable Trp may have beneficial effects on emotional and cognitive functions.


Assuntos
Disfunção Cognitiva/prevenção & controle , Suplementos Nutricionais , Proteínas Dietéticas do Ovo/uso terapêutico , Fadiga Mental/prevenção & controle , Hidrolisados de Proteína/uso terapêutico , Estresse Psicológico/prevenção & controle , Triptofano/uso terapêutico , Idoso , Antidepressivos/efeitos adversos , Antidepressivos/sangue , Antidepressivos/metabolismo , Antidepressivos/uso terapêutico , Bebidas , Disfunção Cognitiva/sangue , Disfunção Cognitiva/metabolismo , Estudos de Coortes , Depressão/sangue , Depressão/metabolismo , Depressão/prevenção & controle , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Proteínas Dietéticas do Ovo/efeitos adversos , Proteínas Dietéticas do Ovo/metabolismo , Metabolismo Energético , Feminino , Humanos , Fadiga Mental/sangue , Fadiga Mental/metabolismo , Pessoa de Meia-Idade , Nootrópicos/efeitos adversos , Nootrópicos/sangue , Nootrópicos/metabolismo , Nootrópicos/uso terapêutico , Hidrolisados de Proteína/efeitos adversos , Hidrolisados de Proteína/metabolismo , Escalas de Graduação Psiquiátrica , Tempo de Reação , Serotoninérgicos/efeitos adversos , Serotoninérgicos/sangue , Serotoninérgicos/metabolismo , Serotoninérgicos/uso terapêutico , Transtornos do Sono-Vigília/sangue , Transtornos do Sono-Vigília/metabolismo , Transtornos do Sono-Vigília/prevenção & controle , Estresse Psicológico/sangue , Estresse Psicológico/metabolismo , Triptofano/efeitos adversos , Triptofano/sangue , Triptofano/metabolismo
9.
Psychopharmacology (Berl) ; 231(24): 4595-610, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24858376

RESUMO

RATIONALE: Effective functioning of the neurotransmitter serotonin is important for optimal cognitive and emotional function. Dietary supplements able to increase availability to the brain of the precursor amino acid, tryptophan (TRP), and thereby enhance serotonin synthesis, can have measurable impact on these psychological processes. OBJECTIVES: This study involves a randomised controlled trial of a TRP-rich egg-white protein hydrolysate (DSM Nutritional Products Ltd., Switzerland) on plasma amino acids, cognition, mood and emotional processing in older women. METHODS: Following a baseline test day without treatment, 60 healthy women aged 45-65 years received drinks containing either 2 or 4 g of TRP-rich protein hydrolysate product or 3.11 g casein hydrolysate as a control. One hour later, they undertook a 2-h battery of cognitive and emotional tests. RESULTS: The TRP-rich protein hydrolysate produced the expected dose-dependent increase in the ratio of plasma TRP to competing large neutral amino acids. TRP-rich protein hydrolysate (2 g only) prevented both the decline in wellbeing and increase in fatigue seen over the test session in the control group. This treatment dose resulted in a significant shift in emotional processing towards positive words and reduced negative bias in assessing negative facial expressions. Effects on cognition were small and not statistically reliable and are not reported here. However, there was no evidence for any adverse effects. CONCLUSIONS: Consumption of a low dose of TRP-rich protein hydrolysate may have beneficial effects on emotional function that could promote feelings of wellbeing, possibly conferring resistance to deterioration in mood in healthy subjects or depressive episodes.


Assuntos
Afeto/efeitos dos fármacos , Aminoácidos/sangue , Suplementos Nutricionais , Emoções/efeitos dos fármacos , Hidrolisados de Proteína/farmacologia , Idoso , Caseínas , Cognição/efeitos dos fármacos , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Testes Neuropsicológicos , Serotonina/metabolismo , Triptofano/sangue
10.
Int J Oral Maxillofac Surg ; 41(10): 1296-303, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22571863

RESUMO

Adverse effects on the oral mucosa after the use of dermal fillers have been increasingly reported due to their increased use for facial aesthetics. The objective of this study was to evaluate the clinical and histologic effects of two types of product, 10% polymethylmethacrylate and 20mg/ml hyaluronic acid, locally and at long distance, examining initial and late reactions. Each substance was randomly and separately injected in rats' tongues (polymethylmethacrylate, n = 16; hyaluronic acid, n = 18). They were compared with the control group (n = 16) at 3 observation times (7, 60 and 90 days) for clinical analysis, intensity of local inflammatory response (haematoxylin and eosin staining), amount of newly formed blood vessels and macrophages (immunohistochemical assays), density of collagen fibres (picrosirius staining) and systemic migration of the product to the liver and kidney (haematoxylin and eosin staining). The results showed inflammation triggered by the injection of the material, suggesting that both substances cause responses in local tissue, although there was biocompatibility with hyaluronic acid. This research highlights the importance of experimental studies on this subject, since adverse reactions have been observed routinely in dental practice.


Assuntos
Reação a Corpo Estranho/induzido quimicamente , Ácido Hialurônico/toxicidade , Inflamação/induzido quimicamente , Polimetil Metacrilato/toxicidade , Língua/efeitos dos fármacos , Animais , Técnicas Cosméticas/efeitos adversos , Feminino , Mucosa Bucal/efeitos dos fármacos , Neovascularização Patológica/induzido quimicamente , Distribuição Aleatória , Ratos , Ratos Wistar
13.
Antimicrob Agents Chemother ; 45(11): 3216-9, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11600383

RESUMO

The effects of cathelicidins against oral bacteria and clinically important oral yeasts are not known. We tested the susceptibilities of Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis, Streptococcus sanguis, Candida krusei, Candida tropicalis and Candida albicans to the following cathelicidins: FALL39, SMAP29, and CAP18. SMAP29 and CAP18 were antimicrobial, whereas FALL39 did not exhibit antimicrobial activity. Future studies are needed to determine the potential use of these antimicrobial peptides in prevention and treatment of oral infections.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Mamíferos/metabolismo , Boca/microbiologia , Leveduras/efeitos dos fármacos , Animais , Peptídeos Catiônicos Antimicrobianos/farmacologia , Catelicidinas , Contagem de Colônia Microbiana , Testes de Sensibilidade Microbiana
14.
J Clin Microbiol ; 38(10): 3595-607, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11015370

RESUMO

Strains of Candida albicans obtained from human immunodeficiency virus (HIV)-positive individuals prior to their first episode of oral thrush were already in a high-frequency mode of switching and were far more resistant to a number of antifungal drugs than commensal isolates from healthy individuals. Switching in these isolates also had profound effects both on susceptibility to antifungal drugs and on the levels of secreted proteinase activity. These results suggest that commensal strains colonizing HIV-positive individuals either undergo phenotypic alterations or are replaced prior to the first episode of oral thrush. They also support the suggestion that high-frequency phenotypic switching functions as a higher-order virulence trait, spontaneously generating in colonizing populations variants with alterations in a variety of specific virulence traits.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Antifúngicos/farmacologia , Candida albicans/genética , Candidíase Bucal/microbiologia , Candida albicans/efeitos dos fármacos , Candida albicans/isolamento & purificação , Candidíase Bucal/etiologia , Feminino , Variação Genética , Soropositividade para HIV , Humanos , Masculino , Testes de Sensibilidade Microbiana , Fenótipo
15.
Rev. chil. radiol ; 6(4): 133-6, 2000. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-295367

RESUMO

Objetivo. Demostrar que la visualización directa de la cuerda espermática y sus alteraciones en pacientes con un cuadro escrotal agudo permite diagnosticar con alta certeza una torsión testicular, evitando los resultados falsos negativos de los signos indirectos, en especial del estudio Doppler cuando este demuestra flujo intratesticular. Material y métodos. En 6 pacientes con cuadro clínico de torsión y en quienes se detectó flujo intratesticular al examen Doppler (falso negativo para torsión) se efectuó además del examen convencional, el estudio dirigido a la cuerda espermática con traductores lineales de alta resolución para objetivar sus alteraciones en el lado sistomático y su normalidad en el lado asistomático. Resultados. En todos los pacientes se logró demostrar una rotación anómala en la cuerda espermática del lado afectado, cuyas características morfológicas se describen. Se observó además en este lado alteraciones en el flujo venoso determinado por la dificultad en su entorno. Conclusión. La torsión de la cuerda espermática es comúnmente denominada torsión testicular aun cuando la torsión primaria ocurre en el cordón. La exploración ha sido generalmente orientada al estudio del testículo con particular importancia de Doppler, con resultados equívocos en algunas ocaciones. Los cambios estructurales del testículo son poco confiables y de tardía manifestación en el curso de la enfermedad. La demostración de la rotación de la cuerda espermática es un signo directo para torsión altamente confiable para el diagnóstico, especialmente en presencia de flujo intratesticular a la exploración Doppler


Assuntos
Humanos , Masculino , Criança , Adolescente , Cordão Espermático , Torção do Cordão Espermático , Cordão Espermático/anatomia & histologia , Epididimo , Testículo , Transdutores , Ultrassonografia Doppler/estatística & dados numéricos
16.
Rev. chil. radiol ; 6(4): 137-9, 2000. ilus
Artigo em Espanhol | LILACS | ID: lil-295368

RESUMO

El rol de la radiología en el diagnóstico de la pancreatitis aguda (PA) y de sus complicaciones ya ha sido establecido. Las distintas clasificaciones que se han creado para determinar la gravedad de esta enfermedad (dentro de ellas la más conocida es la de Balhtazar) no se correlacionan adecuadamente con el manejo ni con el pronóstico del paciente. Por otra parte, muchos de los términos clínico-radiológicos para caracterizar las PA, no son ampliamente aceptados y más aún, son definidos en forma distintas por los diversos autores. El año 1992 el simposio sobre PA en Atlanta estableció una nueva clasificación con el fin de unificar criterios. Esta clasificación es usada en forma sistemática desde el año 1998 en el Hospital Clínico de la Universidad de Chile, existiendo una buena correlación con la evolución clínica de los pacientes. Se presenta la clasificación de Atlanta 1992, para su difusión y discusión en el resto de los servicio de imágenes del país


Assuntos
Humanos , Pancreatite/classificação , Evolução Clínica , Pancreatite Necrosante Aguda , Pancreatite , Pancreatite/complicações
17.
J Dent Res ; 78(4): 857-68, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10326730

RESUMO

Candida colonization of the oral cavity increases in the elderly. A major predisposing condition is denture use, which also increases in the elderly. To test whether the increase in colonization is age-related in a fashion independent of denture use, we analyzed the frequency (incidence) of carriage, the intensity of carriage, the multiplicity of species, and the genetic relatedness of strains in the oral cavities of 93 test subjects separated into the three age groups: 60 to 69 yr, 70 to 79 yr, and > or = 80 yr. Each age group was further subdivided into subjects with and without dentures, and into males and females. The results demonstrate that the frequency of carriage, the intensity of carriage, and multispecies carriage all increase as a function of age and differ according to gender, in both cases independent of denture use, suggesting that the natural suppression of yeast carriage in the oral cavity breaks down in the elderly. In addition, it is demonstrated that Candida glabrata colonizes the oral cavities of elderly individuals without dentures only after 80 yr of age, suggesting that there are age-related compromising conditions other than denture use in this most elderly age group.


Assuntos
Candida/isolamento & purificação , Boca/microbiologia , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Southern Blotting/métodos , Southern Blotting/estatística & dados numéricos , Candida/genética , Candidíase Bucal/epidemiologia , Candidíase Bucal/microbiologia , Portador Sadio/epidemiologia , Portador Sadio/microbiologia , Impressões Digitais de DNA/métodos , Impressões Digitais de DNA/estatística & dados numéricos , Dentaduras/estatística & dados numéricos , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Distribuição por Sexo , Especificidade da Espécie
18.
J Clin Microbiol ; 37(4): 1035-44, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10074523

RESUMO

Using a strategy to clone large genomic sequences containing repetitive elements from the infectious yeast Candida dubliniensis, the three unrelated sequences Cd1, Cd24, and Cd25, with respective molecular sizes of 15,500, 10,000, and 16,000 bp, were cloned and analyzed for their efficacy as DNA fingerprinting probes. Each generated a complex Southern blot hybridization pattern with endonuclease-digested genomic DNA. Cd1 generated an extremely variable pattern that contained all of the bands of the pattern generated by the repeat element RPS of Candida albicans. We demonstrated that Cd1 does not contain RPS but does contain a repeat element associated with RPS throughout the C. dubliniensis genome. The Cd1 pattern was the least stable over time both in vitro and in vivo and for that reason proved most effective in assessing microevolution. Cd24, which did not exhibit microevolution in vitro, was highly variable in vivo, suggesting in vivo-dependent microevolution. Cd25 was deemed the best probe for broad epidemiological studies, since it was the most stable over time, was the only truly C. dubliniensis-specific probe of the three, generated the most complex pattern, was distributed throughout all C. dubliniensis chromosomes, and separated a worldwide collection of 57 C. dubliniensis isolates into two distinct groups. The presence of a species-specific repetitive element in Cd25 adds weight to the already substantial evidence that C. dubliniensis represents a bona fide species.


Assuntos
Candida/genética , Impressões Digitais de DNA/métodos , Sondas de DNA/genética , Southern Blotting , Candida/classificação , Candida/patogenicidade , Candida albicans/genética , Candidíase/microbiologia , Clonagem Molecular , DNA Fúngico/genética , Variação Genética , Genoma Fúngico , Humanos , Sequências Repetitivas de Ácido Nucleico , Especificidade da Espécie
20.
J Clin Microbiol ; 34(9): 2246-54, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8862593

RESUMO

While the age of the host has been suggested as a determining factor in yeast carriage, no studies in which the genetic relatedness of isolates has been assessed in combination with the frequency and intensity of carriage as a function of host age have been performed in a single geographical locale and over a short time window. Therefore, by using a simple plating protocol to determine the frequency and intensity of carriage, sugar assimilation patterns to determine species, and Southern blot hybridization with the DNA fingerprinting probe Ca3 combined with computer-assisted analysis to determine the genetic relatedness of strains of Candida albicans, yeast carriage was analyzed as a function of age. All test individuals lived in the Iowa City, Iowa, locale and, except for some of the 0.5- to 1.5-year-olds, were dentate. The results demonstrate that for this test population, the frequency, average intensity, predominant species, and genetic relatedness of C. albicans strains varied as a function of host age. In addition, comparison with oral commensal organisms from the Ann Arbor, Mich., locale confirms the geographical specificity of C. albicans strains and the existence of an Iowa City-enriched strain which is most prevalent in elderly individuals.


Assuntos
Candida/isolamento & purificação , Boca/microbiologia , Adolescente , Adulto , Fatores Etários , Candida/classificação , Criança , Pré-Escolar , Humanos , Lactente , Iowa , Pessoa de Meia-Idade
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