A Mouthwash with Cetylpyridinium Chlorideis reducing salivary SARS-CoV-2 viral load in +COVID-19 / Un enjuague con Cloruro de Cetilpiridinio redujo la carga salival del virus SARSCoV-2 en pacientes con Covid-19

Aim: The aim of this randomised, double-blind, placebo-controlled pilot clinical trial is to evaluate the capacity of a mouthwash to reduce SARS-CoV-2 viral load in the saliva of patients with COVID-19. Methods: Twenty-three symptomatic SARS-CoV-2-positive outpatients were selected andrandomised into two groups and registered at NTC 04563689. Both groups rinsed and gargled for one minute with either distilled water (Placebo) or with 0.05% Cetylpyridinium chloride (CPC) plus 0.12% Chlorhexidine (CHX) mouthwash (PERIOAID Intensive Care). Saliva samples were collected before the use of placebo or mouthwash and after 15 minutes and 1 and 2 hours of either of the above treatment. A saliva sample was also taken five days after regular use of placebo or mouthwash twice daily. The virus was detected by qRT-PCR. Results: A great heterogeneity in the viral load values was observed at baseline in both groups for nasopharyngeal and saliva samples. Most of the patients who used the mouthwash (8/12) had a significant decrease in baseline viral load after 15 min (greater than 99% reduction). This inhibitory effect was maintained for up to two hours in 10 of the 12 patients. At five days, SARS-CoV-2 RNA was detectedin only 1 patient from the mouthwash group and in 5 from the placebo group. Conclusions: This study points out that a CPC mouthwash can reduce the viral load in saliva of COVID-positive patients. This finding may be important in transmission control of SARS-CoV-2. Nevertheless, the clinical relevance of CPC mouthwash-reduction on SARS-CoV-2 shedding in saliva requires further study.

Objetivo: El objetivo de este ensayo clínico piloto aleatorizado, doble ciego y controlado con placebo es evaluar la capacidad de un enjuague bucal para reducir la carga viral del SARS-CoV-2 en la saliva de pacientes con COVID-19. Materiales y métodos:Veintitrés pacientes ambulatorios positivos para SARS-CoV-2 sintomáticos fueron seleccionados y aleatorizados en dos grupos y registrados en el NTC 04563689. Ambos grupos se enjuagaron y hicieron gárgaras durante un minuto con agua destilada (placebo) o con cloruro decetilpiridinio al 0 ,05 % (CPC). ) más enjuague bucal con Clorhexidina (CHX) al 0,12% (PERIOAID Intensive Care). Se recolectaron muestras de saliva antes del uso de placebo o enjuague bucal y después de 15 minutos y 1 y 2 horas de cualquiera de los tratamientos anteriores. También se tomó una muestra de saliva cinco días después del uso regular de placebo o enjuague bucal dos veces al día. El virus fue detectado por qRT-PCR. Resultados:Se demostró una gran heterogeneidad en los valores de carga viral al inicio del estudio en grupos ambos para muestras de nasofaringe y saliva. La mayoría de los pacientes que usaron el enjuague bucal (8/12) tuvieron una disminución significativa en la carga viral inicial después de 15 minutos (reducción superior al 99 %). Este efecto inhibidor se mantuvo hasta dos horas en 10 de los 12 pacientes. A los cinco días, se detectó ARN del SARS-CoV-2 en solo 1 paciente del grupo de enjuague bucal y en 5 del grupo de placebo. Conclusiones:Este señala que un enjuague bucal CPC puedereducir la carga viral en saliva de pacientes COVID positivos. Este hallazgo puede ser importante en el control de la transmisión del SARS-CoV-2. Sin embargo, la relevancia clínica de la reducción del enjuague bucal con CPC en la excreción de SARS-CoV-2 en la saliva requiere más estudios.

Periodontal pathogens and tetracycline resistance genes in subgingival biofilm of periodontally healthy and diseased Dominican adults.

OBJECTIVE: The objective of this study was to compare the periodontopathogen prevalence and tetracycline resistance genes in Dominican patients with different periodontal conditions. METHODS: Seventy-seven samples were collected from healthy, gingivitis, chronic (CP) and aggressive (AgP) periodontitis patients. Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Prevotella intermedia, Parvimonas micra, Eikenella corrodens and Dialister pneumosintes and 11 resistance genes were studied by PCR. P. gingivalis fimA genotype was determined. RESULTS: In healthy patients, P. micra and P. intermedia were the most and least frequently detected, respectively. T. forsythia and E. corrodens appeared in 100% of gingivitis patients. Red complex, D. pneumosintes and E. corrodens were significantly more prevalent in CP compared to healthy patients. F. nucleatum and T. denticola were detected more frequently in AgP. A. actinomycetemcomitans was the most rarely observed in all groups. The fimA II genotype was the most prevalent in periodontitis patients. Seven tetracycline-resistant genes were detected. tet(Q), tet(32) and tet(W) showed the greatest prevalence. tet(32) was significantly more prevalent in CP than in healthy patients. CONCLUSIONS: Red complex bacteria and D. pneumosintes were significantly the most prevalent species among periodontitis patients. T. forsythia was the most frequently detected in this population. To our knowledge, this is the first study describing the tet(32) gene in subgingival biofilm from healthy and periodontally diseased subjects. CLINICAL RELEVANCE: This study contributes to the knowledge on the subgingival microbiota and its resistance genes of a scarcely studied world region. Knowing the prevalence of resistance genes could impact on their clinical prescription and could raise awareness to the appropriate use of antibiotics.

[Remote monitoring and follow up of implantable cardioverter defibrillators and cardiac resynchronization therapy devices]. / Monitoreo remoto y seguimiento del paciente con desfibrilador automático implantable y terapia de resincronización cardiaca.

INTRODUCTION: The implantable cardiac devices like regular pacemaker, cardiac resynchronization therapy (CRT) automatic implantable defibrillators (ICD) and CRT associate with ICD (CRTD) are now being used frequently. Patient visits to pacemaker and ICD clinics for review and monitoring, has increases significantly. We present the experience of monitoring via satellite of patients with implantable cardiac devices in Mexico. METHODS: Eighteen patients were selected from the arrhythmia Service Cardiac Electrophysiology and Stimulation of High Specialty Medical Unit (UMAE) of Specialties Hospital Dr. Antonio Fraga Mouret. National Medical Center (NMC) La Raza Mexican Social Security Institute (IMSS), who had a device (CRT, ICD y CRT-D) that is able to send information through the BIOTRONIK Home Monitoring system, from March 2006, to March 2009. RESULTS: We obtained 4,980 transmissions as reports and 149 alerts recorded events, of which 50 were in ventricular fibrillation, 14 in ventricular tachycardia, frequent ventricular extra systoles exceeded by the range allowed in one hour were 25, electrograms default 26; and atrial fibrillation at 11. CONCLUSIONS: The monitoring system via satellite is reliable and useful diagnostic tool, which permits early detection, opportune treatment and effective monitoring of implantable cardiac devices.

Monitoreo remoto y seguimiento del paciente con desfibrilador automático implantable y terapia de resincronización cardiaca / Remote monitoring and follow up of implantable cardioverter defibrillators and cardiac resynchronization therapy devices

Introducción: Actualmente, el monitoreo de algunos dispositivos cardiacos implantables como los marcapasos y el desfibrilador automático, así como la terapia de resincronización cardiaca asociada con desfibrilador automático implantable, son los que se utilizan con mayor frecuencia y el seguimiento de los mismos se puede llevar a cabo por vía satelital; por ello su revisión y monitoreo ha incrementado las visitas presenciales en las clínicas de marcapasos y desfibriladores. A continuación se informa la experiencia de la monitorización vía satélite de dichos dispositivos en un centro hospitalario de tercer nivel. Métodos: Se seleccionaron 18 pacientes de la Clínica de Marcapasos del Servicio de Electro-fisiología y Estimulación Cardiaca de la Unidad Médica de Alta Especialidad del Hospital de Especialidades Dr. Antonio Fraga Mouret, Centro Médico Nacional La Raza del Instituto Mexicano del Seguro Social a los cuales se les había implantado un desfibrilador o resincronizador con capacidad de vigilancia remota vía satélite (Home Monitoring BIOTRONIK, Alemania), de marzo del 2006 a marzo del 2009. Resultados: Como reportes, se obtuvieron 4980 transmisiones y 149 alertas por sucesos registrados, de los cuales 50 fueron de fibrilación ventricular, 14 de taquicardia ventricular, extrasístoles ventriculares frecuentes superadas por el rango permitido en una hora fueron 25, fibrilación auricular en 11. Conclusión: El sistema de vigilancia remota vía satélite es una herramienta de diagnóstico confiable, que permite una detección temprana de las principales arritmias que ocurren en los sujetos con dispositivos cardiacos implantables.

Introduction: The implantable cardiac devices like regular pacemaker, cardiac resynchronization therapy (CRT) automatic implantable defibrillators (ICD) and CRT associate with ICD (CRT-D) are now being used frequently. Patient visits to pacemaker and ICD clinics for review and monitoring, has increases significantly. We present the experience of monitoring via satellite of patients with implantable cardiac devices in Mexico. Methods: Eighteen patients were selected from the arrhythmia Service Cardiac Electrophysiology and Stimulation of High Specialty Medical Unit (UMAE) of Specialties Hospital Dr. Antonio Fraga Mouret. National Medical Center (NMC) La Raza Mexican Social Security Institute (IMSS), who had a device (CRT, ICD y CRT-D) that is able to send information through the BIOTRONIK Home Monitoring system, from March 2006, to March 2009. Results: We obtained 4,980 transmissions as reports and 149 alerts recorded events, of which 50 were in ventricular fibrillation, 14 in ventricular tachycardia, frequent ventricular extra systoles exceeded by the range allowed in one hour were 25, electrograms default 26; and atrial fibrillation at 11. Conclusions: The monitoring system via satellite is reliable and useful diagnostic tool, which permits early detection, opportune treatment and effective monitoring of implantable cardiac devices.

Differential cytokine expression by human dendritic cells in response to different Porphyromonas gingivalis capsular serotypes.

AIM: Capsular polysaccharides play an important role in the virulence of Gram-positive and Gram-negative bacteria. In Porphyromonas gingivalis, six serotypes have been described based on capsular antigenicity and its pathogenicity has been correlated both in vitro and in animal models. This study aimed to investigate the differential response of human dendritic cells (DCs) when stimulated with different P. gingivalis capsular serotypes. MATERIALS AND METHODS: Using different multiplicity of infection (MOI) of the encapsulated strains K1-K6 and the non-encapsulated K(-) strain of P. gingivalis, the mRNA expression levels for interleukin (IL)-1beta, IL-2, IL-5, IL-6, IL-10, IL-12, IL-13, interferon (IFN)-gamma, tumour necrosis factor (TNF)-alpha, and TNF-beta in stimulated DCs were quantified by real-time reverse transcription-polymerase chain reaction. RESULTS: All P. gingivalis capsular serotypes induced a T-helper type 1 (Th1) pattern of cytokine expression. K1- and K2-stimulated DCs expressed higher levels of IL-1beta, IL-6, IL-12p35, IL-12p40, and IFN-gamma and at lower MOI than DCs stimulated with the other strains. CONCLUSIONS: These results demonstrate a differential potential of P. gingivalis capsular serotypes to induce DC responses and a higher capacity of strains K1 W83 and K2 HG184 than other K serotypes to trigger cytokine expression.

[Relationship between periodontal diseases and ascending bacterial infection with preterm delivery]. / Relación entre enfermedad periodontal, infección bacteriana ascendente y patología placentaria con parto prematuro.

BACKGROUND: There is an association between periodontal diseases and preterm delivery. AIM: To assess the relationship between periodontal diseases, ascending bacterial infection and placental pathology with preterm delivery. PATIENTS AND METHODS: A periodontal examination and collection of amniotic fluid and subgingival plaque samples were performed in women with preterm labor with intact membranes, without an evident clinical cause or preterm premature rupture of membranes, without clinical chorioamnionitis or labor and a gestational age between 24 and 34 weeks. Microbial invasion of the amniotic cavity was defined as the presence of a positive amniotic fluid culture. Cervicovaginal infection was defined as a bacterial vaginosis or positive culture of cervix or vagina with a high neutrophil count. Ascending bacterial infection was diagnosed as the microbial invasion of the amniotic cavity by ascending bacteria or cervicovaginal infection. Corioamnionitis, funisitis or vellositis were diagnosed. RESULTS: Fifty-nine women were included: forty-two with preterm labor with intact membranes and seventeen with preterm premature rupture of membranes. The prevalence of periodontal diseases was 93.2%. Microbial invasion of the amniotic fluid was detected in 27.1% of patients. periodontal pathogenic bacteria were isolated in 18.6% of amniotic fluid samples and 71.2% of subgingival plaque samples. The prevalence of ascending bacterial infection was 83.1% and in 72.9% of women it was associated with periodontal disease. Preterm delivery (<37 weeks) occurred in 64.4% of patients and was significantly associated with generalized periodontal disease and with the association of ascending bacterial infection and periodontal diseases. Patients with preterm delivery and generalized periodontal disease had a higher frequency of chorioamnionitis and funisitis. CONCLUSIONS: Generalized periodontal disease and its association with ascending bacterial infection are related to preterm delivery and placental markers of bacterial ascending infection.

Relación entre enfermedad periodontal, infección bacteriana ascendente y patología placentaria con parto prematuro / Relationship between periodontal diseases and ascending bacterial infection with preterm delivery

Background: There is an association between periodontal diseases and preterm delivery. Aim: To assess the relationship between periodontal diseases, ascending bacterial infection and placental pathology with preterm delivery. Patients and methods: A periodontal examination and collection of amniotic fluid and subgingival plaque samples were performed in women with preterm labor with intact membranes, without an evident clinical cause or preterm premature rupture of membranes, without clinical chorioamnionitis or labor and a gestational age between 24 and 34 weeks. Microbial invasion of the amniotic cavity was defined as the presence of a positive amniotic fluid culture. Cervicovaginal infection was defined as a bacterial vaginosis or positive culture of cervix or vagina with a high neutrophil count. Ascending bacterial infection was diagnosed as the microbial invasion of the amniotic cavity by ascending bacteria or cervicovaginal infection. Corioamnionitis, funisitis or vellositis were diagnosed. Results: Fifty-nine women were included: fortytwowith preterm labor with intact membranes and seventeen with preterm premature rupture of membranes. The prevalence of periodontal diseases was 93.2%. Microbial invasion of the amniotic fluid was detected in 27.1% of patients. Periodontal pathogenic bacteria were isolated in 18.6% of amniotic fluid samples and 71.2% of subgingival plaque samples. The prevalence of ascending bacterial infection was 83.1% and in 72.9% of women it was associated with periodontal disease. Preterm delivery (<37 weeks) occurred in 64.4% of patients and was significantly associated with generalized periodontal disease and with the association of ascending bacterial infection and periodontal diseases. Patients with preterm delivery and generalized periodontal disease had a higher frequency of chorioamnionitis and funisitis...

Subgingival microbial profiles in chronic periodontitis patients from Chile, Colombia and Spain.

AIM: To investigate the subgingival microbiota of distinct periodontitis patient populations, in Chile, Colombia and Spain, using identical clinical and bacteriological methods. MATERIAL AND METHODS: In this multicentre study, 114 chronic periodontitis patients were selected. Patients were examined using an identical clinical protocol and pooled subgingival samples were obtained from each patient. Samples were processed in the three laboratories by means of culturing under identical clinical and microbiological protocols. Total anaerobic counts and frequency of detection and proportions of nine periodontal pathogens were calculated. Variables were analysed by means of anova, chi(2), Kruskal-Wallis and Dunn's multiple comparison tests. RESULTS: The Colombian population demonstrated greater severity of periodontitis, with significantly deeper mean probing pocket depth, and had a significantly lower percentage of current smokers. When comparing samples from the three patient populations, the total counts were significantly higher in the Colombian patients. The numbers of putative pathogens differed among groups. Tannerella forsythia was found less frequently in Chilean samples, while Parvimonas micra and enteric rods differed significantly among the three population groups. CONCLUSION: Significant differences among Chile, Colombia and Spain existed regarding the frequency and proportions of specific periodontal pathogens in the subgingival microbiota of periodontitis patients.

Inusual cuerpo extraño intratorácico / Unusual thoracic foreign body

Aunque se reportan con alguna frecuencia cuerpos extraños intratorácicos y casos de empalamiento, resulta habitual dejarlos in situ, sobre todo cuando se deben a proyectiles de arma de fuego y los fragmentos son pequeños. Presentamos el caso de un paciente que recibió en el pecho el disparo de un bolígrafo plástico. Como las radiografías solo mostraban dos pequeños fragmentos de material, se decidió tratar conservadoramente. Sin embargo, el paciente continuó durante seis meses con dolor, infecciones respiratorias y en dos ocasiones hemoptisis, por lo que se decidió la extracción de los fragmentos. En la toracotomía se encontró un pedazo de bolígrafo de 7 cm de longitud, cuyo extremo distal estaba enclavado en el cartílago costal y el proximal adyacente al hilio pulmonar derecho. Se realizó la extracción y resección pulmonar atípica del segmento pulmonar afectado. El paciente se recuperó sin complicaciones ni limitaciones funcionales(AU)

Although thoracic foreign bodies and cases of impalement are frequently reported, they are generally left in situ, mainly when caused by gunshots, and the fragments are small. Here is the case of a patient who suffered a plastic pen shot in his chest. Since X-rays only showed two small fragments, it was decided to treat the patient in the traditional way. However, he continued being affected by pain, respiratory infections and hemoptysis; consequently, the extraction of fragments was decided upon. Thoracotomy disclosed a 7cm long pen fragment whose distal end was embedded into the costal cartilage and proximal end adjacent to right pulmonary hilius. Extraction and atypical pulmonary resection of the injured pulmonary segment were performed. The patient recovered without any complications or functional limitations(AU)

Inusual cuerpo extraño intratorácico / Unusual thoracic foreign body

Aunque se reportan con alguna frecuencia cuerpos extraños intratorácicos y casos de empalamiento, resulta habitual dejarlos in situ, sobre todo cuando se deben a proyectiles de arma de fuego y los fragmentos son pequeños. Presentamos el caso de un paciente que recibió en el pecho el disparo de un bolígrafo plástico. Como las radiografías solo mostraban dos pequeños fragmentos de material, se decidió tratar conservadoramente. Sin embargo, el paciente continuó durante seis meses con dolor, infecciones respiratorias y en dos ocasiones hemoptisis, por lo que se decidió la extracción de los fragmentos. En la toracotomía se encontró un pedazo de bolígrafo de 7 cm de longitud, cuyo extremo distal estaba enclavado en el cartílago costal y el proximal adyacente al hilio pulmonar derecho. Se realizó la extracción y resección pulmonar atípica del segmento pulmonar afectado. El paciente se recuperó sin complicaciones ni limitaciones funcionales(AU)

Although thoracic foreign bodies and cases of impalement are frequently reported, they are generally left in situ, mainly when caused by gunshots, and the fragments are small. Here is the case of a patient who suffered a plastic pen shot in his chest. Since X-rays only showed two small fragments, it was decided to treat the patient in the traditional way. However, he continued being affected by pain, respiratory infections and hemoptysis; consequently, the extraction of fragments was decided upon. Thoracotomy disclosed a 7cm long pen fragment whose distal end was embedded into the costal cartilage and proximal end adjacent to right pulmonary hilius. Extraction and atypical pulmonary resection of the injured pulmonary segment were performed. The patient recovered without any complications or functional limitations(AU)

Detection of Porphyromonas gingivalis in the amniotic fluid in pregnant women with a diagnosis of threatened premature labor.

BACKGROUND: Epidemiologic and randomized controlled studies have shown that periodontal diseases may be associated with preterm labor and delivery of infants with low birth weights. The purpose of the present study was to determine the presence of microbial invasion of the amniotic cavity by periodontopathic bacteria in pregnant women with a diagnosis of threatened premature labor. METHODS: A periodontal examination and collection of amniotic fluid and subgingival plaque samples were performed on women identified as having threatened premature labor (preterm premature rupture of membranes without clinical infection or labor and preterm labor with intact membranes) and a gestational age ranging between 24 and 34 weeks. Samples collected from amniotic fluid and from the four deepest periodontal pockets in each patient were pooled in prereduced transport fluid and cultured. Porphyromonas gingivalis was identified primarily by colony morphology under stereoscopic microscope and rapid biochemical tests. Amniotic fluid or plaque samples were homogenized, DNA was extracted, and polymerase chain reaction (PCR) amplification of 16S rRNA with specific and universal primers was carried out. RESULTS: Twenty-six women with threatened premature labor were included: eight with preterm premature rupture of membranes and 18 with preterm labor with intact membranes. Eight women presented with gingivitis, 12 with chronic periodontitis, and six without periodontal disease. Microbial invasion of the amniotic cavity as detected by P. gingivalis PCR was 30.8% (eight of 26 patients). In these eight patients, P. gingivalis was present in both the subgingival samples and the respective amniotic fluid sample. CONCLUSION: The presence of microbial invasion of the amniotic cavity by P. gingivalis could indicate a role for periodontal pathogenic bacteria in pregnant women with a diagnosis of threatened premature labor.

High expression levels of receptor activator of nuclear factor-kappa B ligand associated with human chronic periodontitis are mainly secreted by CD4+ T lymphocytes.

BACKGROUND: Chronic periodontitis is an infectious disease characterized by alveolar bone destruction and teeth loss. Receptor activator of nuclear factor-kappa B ligand (RANKL) is an osteoclastogenic cytokine, a central regulatory factor in the osteoclast's lifespan, and a participant in physiological and pathological bone resorption. Gingival T cells synthesize RANKL, contributing to molecular local imbalance that entails the alveolar bone resorption seen in periodontitis. Our study was aimed at associating the levels of RANKL with the CD4(+) T-cell activity present in gingival tissues of chronic periodontitis patients. METHODS: Gingival biopsies were obtained from 33 chronic periodontitis patients and 20 healthy controls. Specimens were either formalin fixed and paraffin embedded for real-time reverse transcription-polymerase chain reaction (RT-PCR) and histologic analysis or tissue digestion processed for cell culture and flow-cytometry analysis. RANKL mRNA and protein levels were determined by quantitative RT-PCR and enzyme-linked immunosorbent assay (ELISA) in gingival-cell culture supernatants. Gingival leukocytes were quantified by flow cytometry. RANKL and CD4 immunoreactivity were analyzed by flow cytometry and confocal microscopy. RESULTS: RANKL mRNA levels were higher in patients with periodontitis than in healthy subjects, and spontaneous and lipopolysaccharide (LPS)- and phytohemagglutinin (PHA)-stimulated RANKL synthesis were higher also in patients than controls. CD4(+) T lymphocytes were the predominant infiltrate cell subset present in gingival tissues of periodontitis patients. Furthermore, an association between RANKL and CD4(+) T cells was determined by double-staining flow cytometry and confocal microscopy. CONCLUSION: Taken together, these data demonstrate that gingival CD4(+) T cells are the main cells responsible for higher levels of RANKL observed in human chronic periodontitis patients.

Prevalence of periodontopathic bacteria in aggressive periodontitis patients in a Chilean population.

BACKGROUND: Actinobacillus actinomycetemcomitans is considered a major etiologic agent of aggressive periodontitis (AgP). Other periodontopathic bacteria such as Porphyromonas gingivalis are also suspected of participating in aggressive periodontitis although the evidence to support this is controversial. The aim of the present study was to determine the prevalence of eight periodontopathic bacteria in Chilean patients with AgP. METHODS: Subgingival plaque samples were collected from 36 aggressive, 30 localized, and six generalized periodontitis patients. Samples from 17 advanced chronic periodontitis (CP) patients were taken as controls. Samples collected from the four deepest periodontal pockets in each patient were pooled in prereduced transport fluid (RTF) and cultured. Periodontal bacteria were primarily identified by colony morphology under stereoscopic microscope and rapid biochemical tests. The identity of some bacterial isolates was confirmed by colony polymerase chain reaction (PCR). RESULTS: AgP showed a significatively higher prevalence of C. rectus than CP (P = 0.036). The only statistical difference found was for C. rectus. Patients with AgP showed a higher, but not statistically significant, prevalence of P. gingivalis, E. corrodens, P. micros, and Capnocytophaga sp. A similar prevalence in both groups of patients was observed for F. nucleatum and P. intermedia/nigrescens, and A. actinomycetemcomitans was less prevalent in AgP than CP patients. In localized AgP, P. intermedia/nigrescens, E. corrodens, F. nucleatum, and P. micros were the more prevalent pathogens in contrast to generalized AgP patients who harbored A. actinomycetemcomitans, P. gingivalis, and Capnocytophaga sp. as the most prevalent bacteria. CONCLUSIONS: C. rectus, P. gingivalis, E. corrodens, P. micros, and Capnocytophaga sp. were the most predominant periodontopathic bacteria of AgP in this Chilean population, but the only statistical difference found here between AgP and CP was for C. rectus, suggesting that the differences in clinical appearance may be caused by factors other than the microbiological composition of the subgingival plaque of these patients. In this study, the prevalence of A. actinomycetemcomitans was much lower than that of P. gingivalis.

Genetic determination of ploidy level in Xanthophyllomyces dendrorhous.

Xanthophyllomyces dendrorhous (formely Phaffia rhodozyma) is a basidiomycetous yeast-like fungus that produces carotenoids useful for the food industry. Recently, its sexual cycle was reported but little is known about its genetic constitution. To inquire into the ploidy state of X. dendrorhous, biased mutant spectrum, genetic complementation and mitotic recombination analysis were used. A wild-type strain was subjected to N-methyl-N'-nitro-N-nitrosoguanidine mutagenic treatment. Auxotrophic and carotene mutants were forced to revert to the wild-type phenotype. Pigment producing and prototroph revertants behaved as diploid except for adenine less mutants. These results are in agreement with the limited spectrum of auxotrophs obtained in this strain for the ADE1 locus. To analyze the genetic characteristic of the adenine genetic marker of X. dendrorhous, protoplast fusion experiments with several adenine less mutants were performed. The experiments presented in this work suggest that the ATCC 2430 (UDC 67-385) strain of X. dendrorhous is diploid and a heterozygous constitution is proposed for the ADE1 locus.

Estudio genético molecular de levaduras de diversos ambientes / Molecular genetic study of yeasts from different environments

Se describe la presencia de polimorfísmo genético en levaduras nativas aisladas de diferentes ambientes, tales como: agua de mar, suelos forestales con poca intervención antrópica, suelos de viñedos, otros ambientes naturales y desde pacientes con fungemia severa. Se detectó la presencia de elementos genéticos extracromosómicos en cuatro cepas diferentes de levaduras. El análisis de amplificación de una región ITS utilizando partidores específicos para el ITS2 (partidores ITS3 e ITS4), permite determinar una banda de amplificación de rDNA que varia de tamaño entre 450 y 560 pb. dependiendo del género de levadura analizada. En una cepa de Cryptococcus terreus se observó la presencia de tres bandas de amplificación ITS que sugieren una organización compleja de los genes de rDNA en esa cepa. Finalmente el análisis del cariotipo electroforético de cepas ambientales y clínicas de Pichia anomala mostró un marcado polimorfísmo cromosómico en esta levadura emergente.

Anestesia en cirugía plástica ambulatoria / Anesthesia in the plastic surgery outpatient

En los últimos años, la anesteisología, ha evoluciionado en sus técnicas además de contar en la actualidad con drogas de acción corta y rápida metabilización. La cirugía plástica con tendencia ambulatoria, ha recurrido al anestesiólogo para brindar seguridad y calidad al paciente en la intervención. Teniendo en cuenta el tipo de cirugía y características propias del paciente, la permanencia del mismo en la institución, una vez finalizada la intervención, puede variar entre 60 y 180 minutos. Todo esto es factible por tratarse de pacientes generalmente sanos que recurren a la cirugía por decisión propia, asociado a la anestesia local realizada por el cirujano. Existen por lo tanto, para este tipo de cirugías, métodos anestésicos que abarcan desde la sedación hasta la anestesia general; la Neuroleptoanalgesia, técnica que se desarrolla en el presente trabajo, tiene un papel muy importante

Anestesia en cirugía plástica ambulatoria / Anesthesia in the plastic surgery outpatient

En los últimos años, la anesteisología, ha evoluciionado en sus técnicas además de contar en la actualidad con drogas de acción corta y rápida metabilización. La cirugía plástica con tendencia ambulatoria, ha recurrido al anestesiólogo para brindar seguridad y calidad al paciente en la intervención. Teniendo en cuenta el tipo de cirugía y características propias del paciente, la permanencia del mismo en la institución, una vez finalizada la intervención, puede variar entre 60 y 180 minutos. Todo esto es factible por tratarse de pacientes generalmente sanos que recurren a la cirugía por decisión propia, asociado a la anestesia local realizada por el cirujano. Existen por lo tanto, para este tipo de cirugías, métodos anestésicos que abarcan desde la sedación hasta la anestesia general; la Neuroleptoanalgesia, técnica que se desarrolla en el presente trabajo, tiene un papel muy importante

Formación y regeneración de protoplastos de phaffia rhodozyma / Formation and regeneration of phaffia rhodozyma protoplasts

En este trabajo se describe la preparación y regeneración de protoplastos a partir de cultivos frescos de la levadura carotenogénica phaffia rhodozyma, en forma eficiente y con un alto grado de rendimiento en la sobrevida de las células tratadas. Para ello se han realizado una serie de experimentos para formar protoplastos de p.rhodozyma, utilizando tres cepas silvestres y cinco cepas afectadas en carotenogénesis. Se probó las enzimas bioglucanasa, biocelulasa, bioxilanasa, glucoronidasa, zimoliasa 100T, lisozima y novozima 234, encontrándose que novozima 234, es la que tiene mayor eficiencia. En las cepas silvestres UCD 67-210 y UCD 67-385 y las cinco cepas de color, se logra un 100 porciento de protoplastos entre 60 a 90 minutos de tratamiento con novozima a 37ºC. Sin embargo, no fue posible formar protoplastos en ninguna de las condiciones estudiadas con las cepas silvestres UCD 67-383. Tales resultados pueden ser devidos a diferencias en la pared celular entre dichas cepas. Además, se ha observado que la incubación a 37ºC reduce notablemente la sobrevida de las células tratadas. Para la formación y regeneración de protoplastos se utilizó una serie de condiciones, encontrando que un sorbitol 0.2 M la destrucción de las células es menor que a concentraciones de sorbitol 0.8 y 1 M. Sin embargo, el medio más adecuado para la formación y regeneración de los protoplastos debe contener KC1 0.8 M como agente osmolar, manteniendo la isotonía del medio y logrando que la destrucción celular sea menor

Presencia de plasmidos de DNA de doble hebra en phaffia rhodozyma / Presence of double stranded plasmid DNA in phaffia rhodozyma

El análisis mediante electroforesis en gel de agarosa, de los ácidos nucleicos de tres cepas silvestres de phaffia rhodozyma, permitió determinar la presencia de elementos genéticos extracromosómicos de DNA de doble hebra en una de ellas, la cepa UCD 67-210. Esta cepa es portadora de al menos 6 bandas de DNA cromosómico y cuyos tamaños moleculares corresponden a 6.5, 5.9, 5.0, 4.4, 3,2 y 2.5 kb. Con el objetivo de determinar el tipo de ácido nucleico que constituye estos elementos, se estudió su comportamiento frente a diferentes nucleasas. El tratamiento con ribonucleasa A, ya sea en alta o baja fuerza iónica, no tiene efecto sobre las bandas electroforéticas, así como el tratamiento con nucleasa SI. Por el contrario, el tratamiento con desoxiribonucleasa pancreática conduce a una degradación completa de las bandas y del DNA cromosómico. Estos resultados sugieren que la naturaleza química de los plásmidos corresponde a DNA de doble hebra. Por otra parte, la visualización de los plásmidos en gel de agarosa, depende de la utilización de proteinasa K y SDS en el procedimiento de purificación de los plásmidos y en las condiciones de corrida electroférica, sugiriendo la presencia de un complejo DNA plásmidial-proteína en cada uno de estos elementos. Finalmente, el análisis mediante enzimas de restricción de dos de estos plásmidos, sugiere que estos elementos no están relacionados

Efectos de ketoconazol, clotrimazol, nistatina y cicloheximida sobre el crecimiento de phaffia rhodozyma / Effects of ketoconazole, clotrymazole, nystatin and cycloheximide on the growth of phaffia rhodozyma

Debido a la importancia biotecnológica en la producción de pigmentos, se determinaron los niveles de sensibilidad a antifúngicos de 3 cepas de Phaffia rhodozyma, con la finalidad de obtener mutantes resistentes, característica usada como marcador en el análisis genético de diferentes microorganismos. El desarrollo de las tres cepas, fue inhibido por ketoconazol, clotrimazol, nistatina y cicloheximida respectivamente. La cepa UCD 67-210 resultó ser la más sensible al ketoconazol, siendo inhibida por concentraciones de 5 ug/ml de dicho compuesto. Para las cepas UCD 67-383 y UCD 67-385 se requieren concentraciones de 20 ug/ml. El cotrimazol, inhibió el crecimiento de las cepas UCD 67-210 y UCD 76-385, a una concentración de 10 ug/ml y a la cepa UCD 67-383 a 20 ug/ml. La nistatina inhibe el crecimiento de las cepas UCD 67-383 y UCD 67-385 a una concentración de 3 ug/ml y a la cepa UCD 67-210 a 5 ug/ml. La cicloheximida impide el desarrollo de las cepas UCD 67-210 y UCD 67-385 a una concentración de 2 ug/ml. La cepa UCD 67-383 resultó ser la más resistente, requiriéndose concentraciones sobre 6 ug/ml para inhibir su crecimiento