Lentes de contacto y disbiosis ocular, de lo transitorio a lo patológico / Contact lenses and ocular dysbiosis, from the transitory to the pathological

La microbiota ocular normal está compuesta por diferentes comunidades bacterianas Gram negativas y positivas que actúan en la superficie ocular como comensales. Un desequilibrio en la homeostasis de las especies nativas o disbiosis desencadena alteraciones funcionales que eventualmente pueden conllevar afecciones oculares, señalándose al uso de lentes de contacto como el factor predisponente más relevante. Mediante una revisión bibliográfica que incluyó artículos científicos publicados entre el año 2018 y 2022, se analizó la relación entre la microbiota ocular sana, la disbiosis asociada al uso de lentes de contacto que desencadena afecciones oculares. La microbiota ocular en individuos sanos, se compone principalmente por bacterias de los filos: proteobacterias, actinobacteria y firmicutes. Estas comunidades bacterianas al verse asociadas al uso de lentes de contacto desarrollaron disbiosis, observándose un aumento de ciertos géneros como Staphylococcus spp. y Pseudomonas spp., que en condiciones normales son comensales de la superficie ocular, pero al estar aumentada su abundancia condicionan la aparición de diversas afecciones oculares como eventos infiltrativos corneales, queratitis y úlcera corneal bacterianas. Dichas patologías tienden a evolucionar de manera rápida, lo que, sumado a una detección y tratamiento tardíos, puede determinar un pronóstico visual deficiente. Se sugiere que, frente a diversas afecciones de la superficie ocular, los profesionales en el área de oftalmología conozcan la composición de las comunidades de microorganismos que conforman esta microbiota ocular, de manera de distinguir e identificar correctamente el agente causal y, con ello, brindar un tratamiento adecuado y efectivo al usuario (AU)

Normal ocular microbiota is composed of different Gram-negative and positive bacterial communities that act as commensals on the ocular surface. An imbalance in the homeostasis of the native species or dysbiosis triggers functional alterations that can eventually lead to ocular conditions, indicating the use of contact lenses as the most relevant predisposing factor. Through a bibliographic review that added scientific articles published between 2018 and 2022, the relationship between healthy ocular microbiota and dysbiosis associated with the use of contact lenses that trigger ocular conditions was analyzed. The ocular microbiota in healthy individuals is mainly composed of bacteria from the phyla: proteobacteria, actinobacteria and firmicutes. These bacterial communities associated with the use of contact lenses develop dysbiosis, observing an increase in certain genera such as Staphylococcus spp. and Pseudomonas spp., which under normal conditions are commensals of the ocular surface, but as their abundance is increased, they condition the appearance of various ocular conditions such as corneal infiltrative events, bacterial keratitis and corneal ulcer. These pathologies tend to evolve rapidly, which, added to late detection and treatment, can lead to a poor visual prognosis. It is suggested that professionals in the ophthalmology area learn about the composition of the communities of microorganisms that make up this ocular microbiota, in order to correctly distinguish and identify the causative agent, thereby providing a adequate and effective treatment to the user (AU)

Contact lenses and ocular dysbiosis, from the transitory to the pathological.

Normal ocular microbiota is composed of different Gram-negative and positive bacterial communities that act as commensals on the ocular surface. An imbalance in the homeostasis of the native species or dysbiosis triggers functional alterations that can eventually lead to ocular conditions, indicating the use of contact lenses as the most relevant predisposing factor. Through a bibliographic review that added scientific articles published between 2018 and 2022, the relationship between healthy ocular microbiota and dysbiosis associated with the use of contact lenses that trigger ocular conditions was analyzed. The ocular microbiota in healthy individuals is mainly composed of bacteria from the phyla: Proteobacteria, Actinobacteria and Firmicutes. These bacterial communities associated with the use of contact lenses develop dysbiosis, observing an increase in certain genera such as Staphylococcus spp. and Pseudomonas spp., which under normal conditions are commensals of the ocular surface, but as their abundance is increased, they condition the appearance of various ocular conditions such as corneal infiltrative events, bacterial keratitis and corneal ulcer. These pathologies tend to evolve rapidly, which, added to late detection and treatment, can lead to a poor visual prognosis. It is suggested that professionals in the ophthalmology area learn about the composition of the communities of microorganisms that make up this ocular microbiota, in order to correctly distinguish and identify the causative agent, thereby providing a adequate and effective treatment to the user.

Caracterización y diferenciación de cafés, a partir de espectroscopía infrarroja / Characterization and differentiation of coffee from infrared spectroscopy

RESUMEN El café es la segunda bebida más consumida en el mundo después del agua, en el que Colombia contribuye con el 9% de la producción, destacándose la calidad del café del departamento del Huila (cafés de altura); sin embargo, no hay suficiente evidencia sobre la incidencia de la altura en la calidad sensorial y composición química. En ese sentido, se buscó caracterizar y diferenciar cafés, mediante el análisis del espectro infrarrojo (FTIR) y evaluación sensorial. 62 muestras de cafés especiales fueron caracterizados, cosechados en diferentes altitudes, obtenidas en dos periodos de cosecha. Los espectros obtenidos permitieron encontrar diferenciación en los picos asociados a ácidos clorogénicos (1600-1650cm-1), entre grano verde y tostado, aunque no se observaron diferencias en los picos, según el periodo de cosecha, por sí solos. La evaluación sensorial, según la metodología SCA, 2015, no generaron diferencias estadísticamente significativas entre periodos de cosecha y variedades evaluadas. Al considerar conjuntamente el análisis sensorial y el análisis del espectro infrarrojo, se presentaron diferencias estadísticamente significativas entre periodos de cosecha, atribuibles al contenido de cafeína y al puntaje total en taza. Los resultados encontrados muestran que no existe correlación entre la altura del cultivo de café y la calidad final de la bebida.

ABSTRACT Coffee is the second most consumed beverage in the world after water, the Colombian coffee production contributes with 9% of total world production and Colombian coffee is recognized by quality and mild coffee. Today, there is not enough evidence on the influence of altitude in sensory quality and coffee chemical composition. In this sense, we sought to characterize and differentiate coffees by infrared spectrum analysis (FTIR) and sensory evaluation. 62 specialty coffees samples were harvested at different altitudes, obtained in two harvest periods. The spectra obtained allowed finding differentiation in the peaks associated with chlorogenic acids (1600-1650cm-1) between green and roasted coffee beans, although no differences were observed in the peaks according to the harvest period; by itself. The sensory evaluation, according to the SCA methodology, 2015 did not generate statistically significant differences between harvest periods and evaluated varieties. When jointly considering the sensory analysis and the infrared spectrum analysis, there were statistically significant differences between harvest periods, attributable to the caffeine content and the total cup score. The results found show that there is no correlation between the height of the coffee crop and the final quality of the beverage.

Short communication: The gain-of-function Y581S polymorphism of the ABCG2 transporter increases secretion into milk of danofloxacin at the therapeutic dose for mastitis treatment.

The ATP-binding cassette transporter ABCG2 restricts the exposure of certain drugs and natural compounds in different tissues and organs. Its expression in the mammary gland is induced during lactation and is responsible for the active secretion of many compounds into milk, including antimicrobial agents. This particular function of ABCG2 may affect drug efficacy against mastitis and the potential presence of drug residues in the milk. Previous in vitro and in vivo studies showed increased transport of several compounds, including fluoroquinolones, by the bovine ABCG2 Y581S polymorphism. Our main purpose was to study the potential effect of this bovine ABCG2 polymorphism on the secretion into milk of the antimicrobial danofloxacin administered at the therapeutic dose of 6mg/kg used for mastitis treatment. In addition, the effect of this polymorphism on the relative mRNA and protein levels of ABCG2 by quantitative real-time PCR and Western blot were studied. Danofloxacin 18% (6mg/kg) was administered to 6 Y/Y homozygous and 5 Y/S heterozygous cows. Danofloxacin levels in milk and milk-to-plasma concentration ratios were almost 1.5- and 2-fold higher, respectively, in Y/S cows compared with the Y/Y cows, showing a higher capacity of this variant to transport danofloxacin into milk. Furthermore, the higher activity of this polymorphism is not linked to higher ABCG2 mRNA or protein levels. These results demonstrate the relevant effect of the Y581S polymorphism of the bovine ABCG2 transporter in the secretion into milk of danofloxacin after administration of 6mg/kg, with potentially important consequences for mastitis treatment and for milk residue handling.

Involvement of breast cancer resistance protein (BCRP/ABCG2) in the secretion of danofloxacin into milk: interaction with ivermectin.

Danofloxacin, a veterinary fluoroquinolone antimicrobial drug, is actively secreted into milk by an as yet unknown mechanism. One of the main determinants of active drug secretion into milk is the transporter (BCRP/ABCG2). The main purpose was to determine whether danofloxacin is an in vitro substrate for Bcrp1/BCRP and to assess its involvement in danofloxacin secretion into milk. In addition, the role of potential drug-drug interactions in this process was assessed using ivermectin. Danofloxacin was transported in vitro by Bcrp1/BCRP, and ivermectin efficiently blocked this transport. Experiments with Bcrp1(-/-) mice showed no evidence of the involvement of Bcrp1 in plasma pharmacokinetics of danofloxacin. However, the milk concentration and milk-to-plasma ratio of danofloxacin were almost twofold higher in wild-type compared with Bcrp1(-/-) mice. The in vivo interaction with ivermectin was studied in sheep after co-administration of danofloxacin (1.25 mg/kg, i.m.) and ivermectin (0.2 mg/kg, s.c.). Ivermectin had no significant effect on the plasma levels of danofloxacin but significantly decreased danofloxacin concentrations in milk by almost 40%. Concomitant administration of multiple drugs, often used in veterinary therapy, may not only affect their pharmacological activity but also their secretion into milk, because of potential drug-drug interactions mediated by BCRP.

Síndrome hemolítico urémico en Chile: presentación clínica, evolución y factores pronósticos / Hemolytic-uremic syndrome in Chile: clinical features, evolution and prognostic factors

Background: Hemolytic-uremic syndrome (HUS) is characterized by acute renal failure, microangiopathic hemolytic anemia and thrombocytopenia. Aim: To describe the characteñstics ofpatients with the diagnosis ofHUS in Chile, and to identify the most reliable early predictors oímorbidity and moñality. Material and methods: The clinical records ofpatients with HUS aged less than 15 years, attended between January 1990 and December 2003 in 15 hospitals, were reviewed. Demographic, clinical, biochemical, hematological parameters, morbidity and mortality were analyzed. Results: A cohort of 587 patients aged 2 to 8 years, 48 percent males, was analyzed. Ninety two percent had diarrhea. At the moment of diagnosis, anuria was observed in 39 percent of the patients, hypertension in 45 percent and seizures in 17 percent. Forty two percent required renal replacement therapy (RRT) and perítoneal dialysis was used in the majoríty of cases (78 percent). The most frequently isolated etiological agentwas Escherichia coli. Mortality rate was 2.9 percent in the acute phase of the disease and there was a positive correlation between mortality and anuria, seizures, white blood cell count (WCC) >20.000/mm³ and requirements of renal replacement therapy (p <0.05). Twelve percent of patients evolved to chronic renal failure and the risk factors during the acute phase were the need for renal replacement therapy, anuria, WCC >20.000/mm³, seizures and hypertension. Conclusions: The present study emphasizes important clinical and epidemiological aspeets ofHUSin a Chilean pediatricpopulation.

[Hemolytic-uremic syndrome in Chile: clinical features, evolution and prognostic factors]. / Síndrome hemolítico urémico en Chile: presentación clínica, evolución y factores pronósticos.

BACKGROUND: Hemolytic-uremic syndrome (HUS) is characterized by acute renal failure, microangiopathic hemolytic anemia and thrombocytopenia. AIM: To describe the characteristics of patients with the diagnosis of HUS in Chile, and to identify the most reliable early predictors of morbidity and mortality. MATERIAL AND METHODS: The clinical records of patients with HUS aged less than 15 years, attended between January 1990 and December 2003 in 15 hospitals, were reviewed. Demographic, clinical, biochemical, hematological parameters, morbidity and mortality were analyzed. RESULTS: A cohort of 587 patients aged 2 to 8 years, 48% males, was analyzed. Ninety two percent had diarrhea. At the moment of diagnosis, anuria was observed in 39% of the patients, hypertension in 45% and seizures in 17%. Forty two percent required renal replacement therapy (RRT) and peritoneal dialysis was used in the majority of cases (78%). The most frequently isolated etiological agent was Escherichia coli. Mortality rate was 2.9% in the acute phase of the disease and there was a positive correlation between mortality and anuria, seizures, white blood cell count (WCC)>20.000/mm3 and requirements of renal replacement therapy (p<0.05). Twelve percent of patients evolved to chronic renal failure and the risk factors during the acute phase were the need for renal replacement therapy, anuria, WCC>20.000/mm3, seizures and hypertension. CONCLUSIONS: The present study emphasizes important clinical and epidemiological aspects of HUS in a Chilean pediatric population.

Síndrome hemolítico urémico en Santiago de Chile: evolución de la función renal y factores pronósticos / Hemolytic uremic syndrome (HUS), prognostic factors and follow up of renal function, in Santiago, Chile

Introducción: El Síndrome Hemolítico Urémico (SHU) se caracteriza por falla renal aguda, anemia hemolítica microangiopática y trombocitopenia; es la causa más frecuente de insuficiencia renal aguda en la infancia. Objetivo: a) Describir las características actuales del cuadro inicial de SHU en nuestro medio y comparar con lo descrito anteriormente; b) Describir la evolución a 1 año plazo y evaluar posibles factores pronósticos de función renal. Sujetos y Métodos: Se estudiaron variables demográficas, presentación clínica, exámenes bioquímicos y hematológicos, en 374 pacientes con SHU diagnosticados entre Enero 1990 a Diciempe 2002 en 9 hospitales de la Región Metropolitana; se evaluó además función renal al año de seguimiento en una muestra de 213 pacientes y se identificaron factores pronósticos de insuficiencia renal crónica y mortalidad utilizando el análisis de regresión logística. Resultados: Se analizaron 374 pacientes, 50,5 por ciento mujeres, 65,5 por ciento de la Región Metropolitana, edad promedio 1,5 ± 1,4 años (0,2 a 8); 91 por ciento presentó diarrea, 31 por ciento ocurrió en verano, al ingreso 57 por ciento presentó anuria, 43,3 por ciento hipertensión arterial y convulsiones 23 por ciento. Al alta 28 por ciento persistía hipertenso. Las terapias de sustitución renal utilizadas fueron: diálisis peritoneal (50 por ciento), hemodiafiltración (6 por ciento) y hemodiálisis (3 por ciento); recibió plasmaféresis 1 por ciento. Se aisló agente etiológico en 17 por ciento, siendo en 69 por ciento E. coli enterohemorrágica. La mortalidad fue de 2,7 por ciento, siendo la causa principal la falla orgánica múltiple. En el seguimiento al año: 80 por ciento mantuvo función renal normal, 14 por ciento presento deterioro de la función renal, 6 por ciento proteinuria y 4 por ciento hipertensión. Se encontró significativo como factor pronóstico de daño renal: hipertensión arterial (p < 0,0001), necesidad de peritoneodiálisis y hemodiálisis (p: 0,001, p: 0,0015 respectivamente), anuria (p: 0,005) y convulsiones (p: 0,01). Se correlacionó con mortalidad en la etapa aguda: convulsiones, requerimiento de hemodiafiltración y plasmaféresis, (p < 0,0001, p: 0,0001 y p < 0,0001 respectivamente).

Acute and chronic otitis media and Turicella otitidis: a controversial association.

Turicella otitidis is a non-fermenting Gram-positive bacillus isolated almost exclusively from ear exudates. Its significance in acute or chronic otitis media is controversial. Over a 12-month period, T. otitidis was isolated from nine ear exudates from seven patients. Most of these were cases of spontaneous drainage following recurrence of otitis media after antimicrobial therapy that was ineffective against T. otitidis. The MICs of penicillin, levofloxacin, linezolid and vancomycin were very low for all the isolates studied, but most isolates displayed high resistance to macrolides and lincosamides.

Diálisis peritoneal crónica pediátrica en Chile: estudio multicéntrico / Chronic peritoneal dialysis in paedriatrics: the chilean experience

Introducción: La iniciación de la diálisis peritoneal continua ambulatoria en Chile desde 1995, ha mejorado el manejo del paciente pediátrico en insuficiencia renal crónica terminal, llegando a constituirse en la terapia de reemplazo renal de elección en espera de un trasplante, especialmente en el niño menor. El objetivo de este estudio fue evaluar en forma retrospectiva el programa de DPCA pediátrica en cuatro centros de la salud pública del país los que reúnen al 90 por ciento de los niños sometidos a este método de sustitución renal, entre 1995 a 2000. Pacientes y método: se recolectaron 129 pacientes < igual 18 años, 97 de los cuales cumplían un seguimiento > igual 6 meses. Se registró características epidemiológicas y demográficos, crecimiento, parámetros metabólicos, adecuación dialítica y complicaciones. El análisis estadístico se realizó utilizando los programas Excel 5.0 Stata para Windows 6.0 y Epi info 6.0. El coeficiente de correlación de Pearson fue usado para estudiar la correlación entre las variables cuantitativas y el test de chi-cuadrado para variables cualitativas. Análisis de regresión múltiple para la relación entre la respuesta cuantitativa y las variables predictoras y la curva de Kaplan-Meier para las probabilidades de egreso del programa. Se consideró significativo p<0,05. Resultados: edad promedio: 8,6 ñ 4,7 años (rango: 0,16-16,9), 51 por ciento mujeres. Etiologías: hipo/displasia 26 por ciento, glomerulopatías 17 por ciento, nefropatía del reflujo 15 por ciento, uropatía obstructiva 14 por ciento. La incidencia nacional de la DPCA incrementó en 5 años de 0,37 a 7,9 pac/ por millón/< 18 años y la edad promedio de ingreso disminuyó de 12,5 a 7,9 años. 65 por ciento presentó anemia moderada a severa, la hemoglobina incremento de 8,8 mg/dl a 9,9 mg/dl en 24 meses (p<0,001), y la calcemia de 8,9 mg/dl a 9,3 mg/dl (p>0,05). Se obtuvo una correlación positiva entre paratohormona y F. alcalinas (p<0,004). El índice promedio Z T/E fue -2,2 ñ 1,6 observándose deterioro no significativo de la talla a los 24 meses de seguimiento. La prueba de Equilibrio Peritoneal (PET) demostró un predominio de transportador alto que se mantiene hasta los 36 meses de seguimiento. El Kt/V promedio semanal fue de 2,9 ñ 1,9 y fue significativamente más alto en los pacientes menores de 5 años (p<0,005). La tasa promedio de peritonitis fue de 0,67 epi/pac/año, Staphylococcus (St) aureus fue aislado en la mayoría de los episodios

Occurrence and antimicrobial susceptibility of Ureaplasma parvum (Ureaplasma urealyticum biovar 1) and Ureaplasma urealyticum (Ureaplasma urealyticum biovar 2) from patients with adverse pregnancy outcomes and normal pregnant women.

A recent phylogenetic analysis of Ureaplasma urealyticum resulted in the proposal to divide their 2 biovars into species. We used PCR to compare the distribution of species and the presence of the tet(M) and int-Tn resistance determinants in 63 strains of Ureaplasma spp. isolated from the amniotic fluid of patients with an adverse pregnancy outcome and in 22 strains obtained from the lower genital tract of healthy pregnant women. We also determined the antimicrobial susceptibility of the organisms to erythromycin and tetracycline. U. parvum was the most frequent Ureaplasma species detected in our study. Thus, 50/63 (79.4%) invasive isolates and 17/22 (77.3%) lower genital tract isolates corresponded to U. parvum, whereas 12/63 (19%) invasive isolates and 4/22 (18.2%) non-invasive strains corresponded to U. urealyticum. A mixture of species was found in 2 women. We found no significant differences in the antimicrobial susceptibility of isolates according to species or origin of isolation. Sixty-two strains of Ureaplasma spp. (74.7%) were susceptible to erythromycin, and 21 strains (25.3%) were intermediately susceptible. Sixty-eight isolates (81.9%) were susceptible to tetracycline, 2 strains (2.4%) were intermediate and 13 strains (15.7%) were resistant. DNA sequences related to the tet(M) determinant and the int-Tn gene were found in all tetracycline-resistant isolates.