RESUMEN
The photochemistry of Fe(III) coordinated to natural uronate-containing polysaccharides has been investigated quantitatively in aqueous solution. It is demonstrated that the photoreduction of the coordinated Fe(III) to Fe(II) and oxidative decarboxylation occurs in a variety of uronate-containing polysaccharides. The photochemistry of the Fe(III)-polyuronic acid system generated a radical species during the reaction which was studied using the spin trapping technique. The identity of the radical species from this reaction was confirmed as CO2â¢- indicating that both bond cleavage of the carboxylate and oxidative decarboxylation after ligand to metal charge transfer radical reactions may be taking place upon irradiation. Degradation of the polyuronic acid chain was investigated with dynamic light scattering, showing a decrease in the hydrodynamic radius of the polymer assemblies in solution after light irradiation that correlates with the Fe(II) generation. A decrease in viscosity of Fe(IIII)-alginate after light irradiation was also observed. Additionally, the photochemical reaction was investigated in plant root tissue (parsnip) demonstrating that Fe(III) coordination in these natural materials leads to photoreactivity that degrades the pectin component. These results highlight that this Fe(III)-polyuronic acid can occur in many natural systems and may play a role in biogeochemical cycling of iron and ferrous iron generation in plants with significant polyuronic acid content.
RESUMEN
Coordination of Fe(III) to carboxylates in polyuronic acid hydrogels was used to impart photochemical reactivity to polysaccharide-based hydrogels. This photochemical reaction was then used for light-initiated polymerization to create hydrogels with advanced mechanical and conductive properties by capturing the photogenerated radical with a monomer, either acrylamide, methyl methacrylate, or aniline. The photopolymerization of acrylamide using the Fe(III)-polyuronic acid was quantified in solution and the polymerization efficiency was determined under different conditions. Poly(methyl methacrylate) (PMMA)-modified hydrogels were analyzed by the contact angle, optical microscopy, and rheology. This confirmed formation of a stiff, hydrophobic, PMMA layer on polysaccharide hydrogels after light irradiation in methyl methacrylate. Polyaniline-modified hydrogels were characterized by current-voltage sweeps, which showed the formation of conductive polyaniline integrated into the hydrogel after light irradiation in the aniline monomer. This strategy provided a facile approach to create either layered hydrogels with different stiffness and hydrophobicity or hybrid conductive hydrogels using the simple photochemical reaction of blue light irradiation of Fe(III) coordinated to polyuronic acids.
Asunto(s)
Compuestos Férricos , Hidrogeles , Acrilamida/química , Compuestos Férricos/química , Hidrogeles/química , Metacrilatos , Fotoquímica , Polimerizacion , Polimetil Metacrilato , Polisacáridos/químicaRESUMEN
Following the implementation of the new Italian legislation on responsibility of healthcare workers, a multi-professional framework, involving representatives of the Italian public health professionals and legal professionals expert in the field, drafted a proposal of the actionable recommendations to be implemented in the management of civil and penal disputes arising from the practice of public health interventions. In order to prevent legal disputes concerning some public health fields such as vaccinations, cancer screening, environmental health surveillance, and hospital management, it should be primary taken into account to update guidelines in supporting decision-making processes, in accordance with the "best scientific evidence available." Furthermore, a multidisciplinary alliance between public health and legal area professionals should be encouraged and should be promoted both at national and European level.
Asunto(s)
Atención a la Salud , Salud Pública , Europa (Continente) , Instituciones de Salud , Humanos , ItaliaRESUMEN
The importance of healthcare providers' communication abilities is still underestimated. Informing the population on the basis of documented evidence is essential but not enough to induce a change in the beliefs of who is doubtful or does not accept preventive interventions, such as vaccination. Lining up the offer of prevention to the knowledge of the citizens, also improving Health Literacy skills, is a critical step toward their empowerment and behavior change. The 2017 Erice Declaration was drafted to propose to the Institutions and the scientific community the main goals to improve communication and counteract Vaccine Hesitancy, at a very critical time, when mandatory vaccination was introduced in Italy.
Asunto(s)
Comunicación en Salud/métodos , Personal de Salud , Aceptación de la Atención de Salud/psicología , Salud Pública/métodos , Conocimientos, Actitudes y Práctica en Salud , Alfabetización en Salud , Humanos , ItaliaRESUMEN
While polycarboxylates and hydroxyl-acid complexes have long been known to be photoactive, simple carboxylate complexes which lack a significant LMCT band are not typically strongly photoactive. Hence, it was somewhat surprising that a series of reports demonstrated that materials synthesized from iron(III) and polysaccharides such as alginate (poly[guluronan-co-mannuronan]) or pectate (poly[galacturonan]) formed photoresponsive materials that convert from hydrogels to sols under the influence of visible light. These materials have numerous potential applications in areas such as photopatternable materials, materials for controlled drug delivery, and tissue engineering. Despite the near-identity of the functional units in the polysaccharide ligands, the reactivity of iron(III) hydrogels can depend on the configuration of some chiral centers in the sugar units and in the case of alginate the guluronate to mannuronate block composition, as well as pH. Here, using temperature- and field-dependent transmission Mössbauer spectroscopy, we show that the dominant iron compound detected for both the alginate and pectate gels displays features typical of a polymeric (Fe3+O6) system. The Mössbauer spectra of such systems are strongly dependent on temperature, field, size, and crystallinity, indicative of superparamagnetic relaxation of magnetically ordered nanoparticles. Pectate and alginate hydrogels differ in the size distribution of the iron oxyhydroxy nanoparticles, suggesting that in general smaller nanoparticles are more reactive. Potential biological implications of these results are also discussed.
Asunto(s)
Alginatos/química , Complejos de Coordinación/química , Compuestos de Hierro/química , Nanopartículas/química , Pectinas/química , Hidrogeles , Luz , Fenómenos Magnéticos , Tamaño de la Partícula , Espectroscopía de MossbauerRESUMEN
Vaccine hesitancy is an important issue to be addressed, due to the risk of decrease of vaccination coverage and consequent control of preventable diseases. While it is not considered a specific determinant, poor or inadequate communication can contribute to vaccine hesitancy and negatively influence vaccination uptake. As a contribution to the ongoing discussion regarding this theme and in the perspective of the implementation of the upcoming national vaccination plan in Italy, the Erice Declaration was drafted by experts in the field of immunization following a 5-day residential, independent workshop regarding communication topics in vaccinology. The aim of the current letter is to present to the broader international audience such a contribution, proposing the identification of the main actions that should be taken into account and prioritized in order to improve communication in the domain of vaccination.
Asunto(s)
Enfermedades Transmisibles/epidemiología , Transmisión de Enfermedad Infecciosa/prevención & control , Comunicación en Salud , Educación en Salud , Aceptación de la Atención de Salud , Vacunación/estadística & datos numéricos , Educación , Política de Salud , Humanos , ItaliaRESUMEN
Photoresponsive hydrogels were obtained by coordination of alginate-acrylamide hybrid gels (AlgAam) with ferric ions. The photochemistry of Fe(III)-alginate was used to tune the chemical composition, mechanical properties, and microstructure of the materials upon visible light irradiation. The photochemical treatment also induced changes in the swelling properties and transport mechanism in the gels due to the changes in material composition and microstructure. The AlgAam gels were biocompatible and could easily be dried and rehydrated with no change in mechanical properties. These gels showed promise as scaffolds for cartilage tissue engineering, where the photochemical treatment could be used to tune the properties of the material and ultimately change the growth and extracellular matrix production of chondrogenic cells. ATDC5 cells cultured on the hydrogels showed a greater than 2-fold increase in the production of sulfated glycosaminoglycans (sGAG) in the gels irradiated for 90 min compared to the dark controls. Our method provides a simple photochemical tool to postsynthetically control and adjust the chemical and mechanical environment in these gels, as well as the pore microstructure and transport properties. By changing these properties, we could easily access different levels of performance of these materials as substrates for tissue engineering.
Asunto(s)
Cartílago/fisiología , Hidrogeles/efectos de la radiación , Luz , Ingeniería de Tejidos/métodos , Fenómenos Biomecánicos , Células Cultivadas , Condrocitos/citología , Compuestos Férricos/química , Hidrogeles/química , Polisacáridos/química , Ingeniería de Tejidos/instrumentación , Andamios del Tejido/químicaRESUMEN
The Erice Charter was unanimously approved at the conclusion of the 47th Residential Course "Adapted Physical Activity in Sport, Wellness and Fitness: New Challenges for Prevention and Health Promotion", held on 20-24 April 2015 in Erice, Italy, at the "Ettore Majorana" Foundation and Centre for Scientific Culture, and promoted by the International School of Epidemiology and Preventive Medicine "G. D'Alessandro" and the Study Group on Movement Sciences for Health of the Italian Society of Hygiene, Preventive Medicine and Public Health. After an intense discussion the participants identified the main points associated with the relevance of physical activity for Public Health, claiming the pivotal role of the Department of Prevention in coordinating and managing preventive actions. The participants underlined the importance of the physicians specialized in Hygiene, Preventive Medicine and Public Health. The contribution of other operators such as physicians specialized in Sport Medicine was stressed. Further, the holders of the new degree in Human Movement and Sport Sciences were considered fundamental contributors for the performance of physical activity and their presence was seen as a promising opportunity for the Departments of Prevention. Primary prevention based on recreational physical activities should become easily accessible for the population, avoiding obstacles such as certification steps or complex bureaucracy. The Sport Doctor is recognized as the principal referent for preliminary physical evaluation and clinical monitoring in secondary and tertiary prevention actions based on adapted physical activities. Developing research in the field is essential as well as implementing higher education on physical activity management in Schools of Public Health.
Asunto(s)
Promoción de la Salud/métodos , Actividad Motora/fisiología , Salud Pública , Investigación Biomédica , Enfermedad Crónica , Humanos , Italia , Médicos/organización & administración , Prevención Primaria/métodos , EspecializaciónRESUMEN
Visible-light responsive gels were prepared from two plant-origin polyuronic acids (PUAs), alginate and pectate, coordinated to Fe(III) ions. Comparative quantitative studies of the photochemistry of these systems revealed unexpected differences in the photoreactivity of the materials, depending on the polysaccharide and its composition. The roles that different functional groups play on the photochemistry of these biomolecules were also examined. Mannuronic-rich alginates were more photoreactive than guluronic acid-rich alginate and than pectate. The microstructure of alginates with different mannuronate-to-guluronate ratios changed with polysaccharide composition. This influenced the gel morphology and the photoreactivity. Coordination hydrogel beads were prepared from both Fe-alginate and Fe-pectate. The beads were stable carriers of molecules as diverse as the dye Congo Red, the vitamin folic acid, and the antibiotic chloramphenicol. The photoreactivity of the hydrogel beads mirrored the photoreactivity of the polysaccharides in solution, where beads prepared with alginate released their cargo faster than beads prepared with pectate. These results indicate important structure-function relationships in these systems and create guidelines for the design of biocompatible polysaccharide-based materials where photoreactivity and controlled release can be tuned on the basis of the type of polysaccharide used and the metal coordination environment.
Asunto(s)
Alginatos/química , Preparaciones de Acción Retardada/química , Hidrogeles/química , Hierro/química , Pectinas/química , Alginatos/efectos de la radiación , Preparaciones de Acción Retardada/efectos de la radiación , Ácido Glucurónico/química , Ácido Glucurónico/efectos de la radiación , Ácidos Hexurónicos/química , Ácidos Hexurónicos/efectos de la radiación , Hidrogeles/efectos de la radiación , Hierro/efectos de la radiación , Luz , Ensayo de Materiales , Pectinas/efectos de la radiación , Polisacáridos/química , Polisacáridos/efectos de la radiaciónRESUMEN
The present work describes the characterization and thermal properties of hydrophobic starch obtained by the esterification of cassava starch with acyl imidazoles, acid chlorides and methyl ester derivatives of fatty acids with n-alkyl chains with 12-22 carbon atoms, in order to compare the dependence of their properties as a function of the length of the side chain and the methodology used for their synthesis. The n-acyl starches presented degrees of substitution (DS) between 0.06 and 1.2. Most of the derivatives obtained with acyl imidazoles were found to be stable at temperatures up to 300°C, whereas those synthesized with acid chlorides or methyl ester decomposed below. Finally, when the n-acyl starches were substituted with n-alkyl side chains of 16 or more carbon atoms, they were capable to crystallize in separate paraffinic phases independent of the starch backbone.
Asunto(s)
Cloruros/química , Ácidos Grasos/química , Imidazoles/química , Manihot/química , Almidón/química , Calorimetría , Esterificación , Estructura Molecular , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , TermodinámicaRESUMEN
The antigenic structure of Treponema pallidum was described in the 1940s and 1950s. The main contributions of Giuseppe D'Alessandro and his collaborators included the description of the external membrane and of the polysaccharide antigen found in the cell wall of the microorganism. Based on new knowledge it has been possible to develop diagnostic tests that are more sensitive and specific than nontreponemal tests, which nevertheless retain their validity in the current re-emergence of syphilis as a public health problem.
Asunto(s)
Anticuerpos Antibacterianos/historia , Polisacáridos Bacterianos/historia , Salud Pública/historia , Sífilis/historia , Treponema pallidum , Anticuerpos Antibacterianos/inmunología , Cápsulas Bacterianas/inmunología , Historia del Siglo XX , Humanos , Italia , Polisacáridos Bacterianos/inmunología , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Sicilia , Sífilis/diagnóstico , Treponema pallidum/inmunologíaRESUMEN
BACKGROUND: Since a long time, Italy has maintained a dual system to administer childhood immunisations, that is a certain number of mandatory vaccinations and a number of recommended vaccinations. The study aimed to explore the issues surrounding parental acceptance or non-acceptance of the recommended vaccinations for children. METHODS: Parents of children aged 3-5 years of day-care centres in Sicily were asked to fill out an anonymous questionnaire. Determinants of the attitude towards recommended vaccinations and social influence on the decision-making process were assessed using logistic regression analysis. RESULTS: Of the 1,500 selected parents, 81.0% participated in the study. Prior to the survey, the majority of children (97.6%) received recommended vaccines. Most parents (74.4%) received information about vaccinations from Family Paediatricians, showed a good knowledge about the side effects of the vaccines (73.1%), did not worry about their potential dangerousness (53.0%) and would have accepted their children to be vaccinated even if it was not required for day care (84.1%). The majority (79.9%) were not disposed to follow the advises of the anti-vaccination movements. Parents' background characteristics, sources of information and social influence were not significantly associated with parental acceptance of recommended vaccines for childhood. CONCLUSIONS: This study suggests that health information by Family Paediatricians is significantly associated with parental acceptance of recommended vaccinations.
Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Programas de Inmunización/estadística & datos numéricos , Padres/psicología , Vacunas/administración & dosificación , Adulto , Preescolar , Femenino , Guías como Asunto , Humanos , Italia , MasculinoRESUMEN
Phylogenetic analysis of partial rpoB gene sequences of type and clinical strains belonging to different 16S rRNA gene-fingerprinting ribogroups within 11 species of enterobacteria of the genera Proteus, Morganella and Providencia was performed and allowed the definition of rpoB clades, supported by high bootstrap values and confirmed by ≥2.5â% nucleotide divergence. None of the resulting clades included strains belonging to different species and the majority of the species were confirmed as discrete and homogeneous. However, more than one distinct rpoB clade could be defined among strains belonging to the species Proteus vulgaris (two clades), Providencia alcalifaciens (two clades) and Providencia rettgeri (three clades), suggesting that some strains represent novel species according to the genotypes outlined by rpoB gene sequence analysis. Percentage differences between the rpoB gene sequence of the type strain of Proteus myxofaciens and other members of the same genus (17.3-18.9â%) were similar to those calculated amongst strains of the genus Providencia (16.4-18.7â%), suggesting a genetic distance at the genus-level between Proteus myxofaciens and the rest of the Proteus-Providencia group. Proteus myxofaciens therefore represents a member of a new genus, for which the name Cosenzaea gen. nov., is proposed.
Asunto(s)
ARN Polimerasas Dirigidas por ADN/genética , Morganella/clasificación , Filogenia , Proteus/clasificación , Providencia/clasificación , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Genes Bacterianos , Datos de Secuencia Molecular , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
Molecular epidemiology at local scale in Sicily (Italy) of ampicillin resistance in Salmonella spp. isolates from municipal wastewater (n = 64) and clinical specimens (n = 274) is described in comparison with previously examined Escherichia coli isolates (n = 273) from wastewater. High prevalence of antibiotic resistance (28.9%) with highest resistance rates against ampicillin (22.7%) was observed in E. coli isolates. Different resistance rates were observed in Salmonella according to the serovars, with prevalences of the same order in both wastewater and clinical isolates belonging to the same serovar (e.g., 91.7% ampicillin resistance in wastewater isolates vs. 70.8% in clinical isolates of the Salmonella serovar Typhimurium and 0% ampicillin resistance in both wastewater and clinical isolates of the Salmonella serovar Enteritidis). The beta-lactam resistance gene bla(TEM) was present in both wastewater and clinical Salmonella spp. isolates, with the exception of Salmonella enterica serovar Typhimurium isolates with a typical six-drug resistance pattern AmpChlSulTeStrSp that had the bla(PSE-1) gene. The bla(TEM) gene was present in all the E. coli isolates but one had the bla(SHV) gene. Several E. coli and some Salmonella isolates were positive for class 1 integrons with variable regions of 1.0 or 1.5 kb containing aadA1, dfrA17-aadA5, or dfrA1-aadA1 gene cassettes, whereas Salmonella serovar Typhimurium isolates with the six-drug resistance pattern were positive for both 1.0 and 1.2 kb integrons. Polymerase chain reaction replicon typing demonstrated the presence of multireplicon resistance plasmids in several isolates of E. coli, containing two to four of the replicons IncF, IncI1, IncFIA, and IncFIB, whereas other isolates showed resistance plasmids with only IncF, IncP, or IncK replicons. Replicon IncI1 was detected in one Salmonella isolate, whereas other isolates belonging to different serovars had IncN replicons. Analysis of isolates from wastewater can be a useful epidemiologic tool to monitor the prevalence of antibiotic resistance and genetic elements related to antibiotic resistance in Salmonella clones circulating in the human population.
Asunto(s)
Resistencia a la Ampicilina/genética , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Gastroenteritis/epidemiología , Salmonella/efectos de los fármacos , Salmonella/genética , Microbiología del Agua , Antibacterianos/farmacología , Técnicas de Tipificación Bacteriana , Farmacorresistencia Bacteriana/genética , Escherichia coli/clasificación , Escherichia coli/aislamiento & purificación , Heces/microbiología , Gastroenteritis/microbiología , Genes MDR , Humanos , Integrones/genética , Pruebas de Sensibilidad Microbiana , Plásmidos/clasificación , Plásmidos/genética , Vigilancia de la Población/métodos , Salmonella/clasificación , Salmonella/aislamiento & purificación , Salmonella enteritidis/clasificación , Salmonella enteritidis/efectos de los fármacos , Salmonella enteritidis/genética , Salmonella enteritidis/aislamiento & purificación , Salmonella typhimurium/clasificación , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética , Salmonella typhimurium/aislamiento & purificación , Sicilia/epidemiología , Eliminación de Residuos Líquidos , Resistencia betalactámica/genéticaRESUMEN
We have evaluated health and economic benefits of a universal infant vaccination with two rotavirus vaccines registered in Italy, on the bases of the burden of rotavirus gastroenteritis (RVGE) in a birth cohort of 520,000 Italian infants followed until 5 years of age. Estimates from published and unpublished sources of disease burden, costs, vaccine coverage, efficacy trials of both vaccines, and price were used to estimate cost-effectiveness from the perspectives of the Italian National Health Service (NHS) and society. According to our estimates, a universal rotavirus vaccination program would avoid 10,679 hospitalizations, 39,202 emergency visits, and 44,223 at home visits. At 65.6 euro per vaccination courses, the program would cost 30,700,800 euro and realize a net loss of 9,057,928 euro from the Italian NHS perspective. On the contrary, the program would provide a net savings of 24,324,198 euro from the societal perspective. From the Italian NHS perspective, the break-even price per vaccination course should be reduced at least to 46.25 euro to achieve a zero cost-effectiveness ratio.
Asunto(s)
Gastroenteritis/epidemiología , Gastroenteritis/prevención & control , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/prevención & control , Vacunas contra Rotavirus/economía , Vacunas contra Rotavirus/inmunología , Animales , Preescolar , Costo de Enfermedad , Análisis Costo-Beneficio , Gastroenteritis/economía , Humanos , Incidencia , Lactante , Italia/epidemiología , Infecciones por Rotavirus/economía , Vacunación/economía , Vacunación/estadística & datos numéricosRESUMEN
During 2006, 82 samples of human mature milk were collected at Italian hospitals and checked for aflatoxin M1 (AFM1) and ochratoxin A (OTA) by immunoaffinity column extraction and HPLC. AFM1 was detected in four (5%) of milk samples (ranging from < 7 ng/L to 140 ng/L; mean level: 55.35 ng/L); OTA was detected in 61 (74%) of milk samples (ranging from < 5 ng/L to 405 ng/L; mean level: 30.43 ng/L. OTA levels were significantly higher (p less, not double equals 0.05) in milk of habitual consumers of bread, bakery products and cured pork meat. No other statistically significant differences were observed although habitual consumers of pasta (p = 0.059), cookies (p = 0.061) and juices (p = 0.063) had mean contamination values of OTA higher than the moderate consumer. The very few AFB1 positive samples did not allow statistical comparisons. The present study confirms that the occurrence of OTA in human milk is related to maternal dietary habits. The findings support the possibility of dietary recommendations to woman, during pregnancy and lactation, aimed to tentatively reduce the OTA contamination of human milk.
Asunto(s)
Conducta Alimentaria , Leche Humana/química , Madres , Micotoxinas/análisis , Adulto , Aflatoxina M1/análisis , Peso al Nacer , Cromatografía Líquida de Alta Presión , Femenino , Edad Gestacional , Humanos , Recién Nacido , Edad Materna , Ocratoxinas/análisis , EmbarazoRESUMEN
A survey was performed among students of various faculties at the University of Catania (Italy) to examine the health effects of excessive Internet use and behaviour patterns of Internet dependency. Three hundred students were recruited through a non probabilistic quota sampling method and were asked to complete a questionnaire aimed at identifying attitudes and behaviours regarding Internet use, and the psychological and physical consequences of excessive use of the Internet. The most relevant findings that emerged from student responses regard: emotional dependency on the Internet (5% of students believe that Internet facilitates social relationships, 4% experiences euphoric feelings or excitement while on-line, 1% consider the Internet as a way of escaping from real life), the excessive amount of time spent on-line (8%) and the inability to end an on-line session(8%), lying to family members to conceal the nature of involvement with the Internet (3%), giving up sports (2%) or meals (1%), the negative impact on school grades (3%), lack of sleep (4%), and physical health problems such as backache (2%), arm or wrist pain (2%), vision disturbances (6%).
Asunto(s)
Conducta Adictiva , Salud Pública , Humanos , Internet , Estudiantes , Encuestas y CuestionariosRESUMEN
A coryneform bacterium was isolated from the bronchoalveolar aspirate of a patient with interstitial pulmonary inflammation. Commercial systems identified the isolate as Corynebacterium sp. or Aureobacterium sp./Corynebacterium aquaticum, but 16S rRNA gene analysis unequivocally attributed it to the genus Microbacterium. This represents the first documented case of Microbacterium pulmonary infection.
Asunto(s)
Infecciones por Actinomycetales/microbiología , Actinomycetales/clasificación , Actinomycetales/aislamiento & purificación , Trasplante de Corazón/efectos adversos , Neumonía/microbiología , Actinomycetales/genética , Adulto , ADN Bacteriano/análisis , Humanos , Masculino , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genéticaRESUMEN
Until recently, morphotyping, a method evaluating fringe and surface characteristics of streak colonies grown on malt agar, has been recommended as a simple and unexpensive typing method for Candida albicans isolates. The discriminatory power and reproducibility of Hunter's modified scheme of Phongpaichit's morphotyping has been evaluated on 28 C. albicans isolates recovered from the oral cavity of asymptomatic human immunodeficiency virus-positive subjects, and compared to two molecular typing methods: randomly amplified polymorphic DNA (RAPD) fingerprinting, and contour clamped homogeneous electric field (CHEF) electrophoretic karyotyping. Morphological features of streak colonies allowed to distinguish 11 different morphotypes while RAPD fingerprinting yielded 25 different patterns and CHEF electrophoresis recognized 9 karyotypes. The discriminatory power calculated with the formula of Hunter and Gaston was 0.780 for morphotyping, 0.984 for RAPD fingerprinting, and 0.630 for karyotyping. Reproducibility was tested using 43 serial isolates from 15 subjects (2 to 6 isolates per subject) and by repeating the test after one year storage of the isolates. While genetic methods generally recognized a single type for all serial isolates from each of the subjects studied, morphotyping detected strain variations in five subjects in the absence of genetic confirmation. Poor reproducibility was demonstrated repeating morphotyping after one year storage of the isolates since differences in at least one character were detected in 92.9% of the strains.
Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/microbiología , Candida albicans/clasificación , Candidiasis Bucal/microbiología , Técnicas de Tipificación Micológica/métodos , Candida albicans/genética , Candida albicans/aislamiento & purificación , Dermatoglifia del ADN/métodos , Humanos , Reproducibilidad de los ResultadosRESUMEN
Until recently, morphotyping, a method evaluating fringe and surface characteristics of streak colonies grown on malt agar, has been recommended as a simple and unexpensive typing method for Candida albicans isolates. The discriminatory power and reproducibility of Hunter's modified scheme of Phongpaichit's morphotyping has been evaluated on 28 C. albicans isolates recovered from the oral cavity of asymptomatic human immunodeficiency virus-positive subjects, and compared to two molecular typing methods: randomly amplified polymorphic DNA (RAPD) fingerprinting, and contour clamped homogeneous electric field (CHEF) electrophoretic karyotyping. Morphological features of streak colonies allowed to distinguish 11 different morphotypes while RAPD fingerprinting yielded 25 different patterns and CHEF electrophoresis recognized 9 karyotypes. The discriminatory power calculated with the formula of Hunter and Gaston was 0.780 for morphotyping, 0.984 for RAPD fingerprinting, and 0.630 for karyotyping. Reproducibility was tested using 43 serial isolates from 15 subjects (2 to 6 isolates per subject) and by repeating the test after one year storage of the isolates. While genetic methods generally recognized a single type for all serial isolates from each of the subjects studied, morphotyping detected strain variations in five subjects in the absence of genetic confirmation. Poor reproducibility was demonstrated repeating morphotyping after one year storage of the isolates since differences in at least one character were detected in 92.9 percent of the strains.