Differential Antifungal Activity of Human and Cryptococcal Melanins with Structural Discrepancies.

Melanin is a pigment found in all biological kingdoms, and plays a key role in protection against ultraviolet radiation, oxidizing agents, and ionizing radiation damage. Melanin exerts an antimicrobial activity against bacteria, fungi, and parasites. We demonstrated an antifungal activity of synthetic and human melanin against Candida sp. The members of the Cryptococcus neoformans and C. gattii species complexes are capsulated yeasts, which cause cryptococcosis. For both species melanin is an important virulence factor. To evaluate if cryptococcal and human melanins have antifungal activity against Cryptococcus species they both were assayed for their antifungal properties and physico-chemical characters. Melanin extracts from human hair and different strains of C. neoformans (n = 4) and C. gattii (n = 4) were investigated. The following minimum inhibitory concentrations were found for different melanins against C. neoformans and C. gattii were (average/range): 13.7/(7.8-15.6) and 19.5/(15.6-31.2) µg/mL, respectively, for human melanin; 273.4/(125->500) and 367.2/(125.5->500) µg/mL for C. neoformans melanin and 125/(62.5-250) and 156.2/(62-250) µg/mL for C. gattii melanin. Using Scanning Electron Microscopy we observed that human melanin showed a compact conformation and cryptococcal melanins exposed an amorphous conformation. Infrared spectroscopy (FTIR) showed some differences in the signals related to C-C bonds of the aromatic ring of the melanin monomers. High Performance Liquid Chromatography established differences in the chromatograms of fungal melanins extracts in comparison with human and synthetic melanin, particularly in the retention time of the main compound of fungal melanin extracts and also in the presence of minor unknown compounds. On the other hand, MALDI-TOF-MS analysis showed slight differences in the spectra, specifically the presence of a minor intensity ion in synthetic and human melanin, as well as in some fungal melanin extracts. We conclude that human melanin is more active than the two fungal melanins against Cryptococcus. Although some physico-chemical differences were found, they do not explain the differences in the antifungal activity against Cryptococcus of human and cryptococcal melanins. More detailed studies on the structure should be considered to associate structure and antifungal activity.

Fast detection of Piscirickettsia salmonis in Salmo salar serum through MALDI-TOF-MS profiling.

Piscirickettsia salmonis is a pathogenic bacteria known as the aetiological agent of the salmonid rickettsial syndrome and causes a high mortality in farmed salmonid fishes. Detection of P. salmonis in farmed fishes is based mainly on molecular biology and immunohistochemistry techniques. These techniques are in most of the cases expensive and time consuming. In the search of new alternatives to detect the presence of P. salmonis in salmonid fishes, this work proposed the use of MALDI-TOF-MS to compare serum protein profiles from Salmo salar fish, including experimentally infected and non-infected fishes using principal component analysis (PCA). Samples were obtained from a controlled bioassay where S. salar was challenged with P. salmonis in a cohabitation model and classified according to the presence or absence of the bacteria by real time PCR analysis. MALDI spectra of the fish serum samples showed differences in its serum protein composition. These differences were corroborated with PCA analysis. The results demonstrated that the use of both MALDI-TOF-MS and PCA represents a useful tool to discriminate the fish status through the analysis of salmonid serum samples.

Phytophthora austrocedri Elicitates Changes in Diterpene Profile of Austrocedrus chilensis.

The populations of the Andean Cupressaceae Austrocedrus chilensis have been severely affected by a disease caused by the phytopathogenic fungus Phytophthora austrocedri. A study was undertaken to disclose changes in the resin composition of P. austrocedri-infected individuals, including naturally infected and artificially inoculated trees, compared with healthy A. chilensis trees. GC-MS and (1)H-NMR studies showed a clear differentiation among healthy and infected resins, with the diterpene isopimara-8(9),15-dien-19-ol as a relevant constituent in resins from infected trees. The effect of resin fractions from P. austrocedri infected trees on the pathogen was assessed by measuring the mycelial growth in agar plates. The most active fractions from resin obtained from infected trees inhibited fungal growth by nearly 50% at 1 mg/dish (35.37 µg/cm(2)). The main constituent in the active fractions were 18-hydroxymanool and the aldehyde torulosal. Both compounds are oxidation products of manool and can be a chemical response of the tree to the pathogen or be formed from the pathogen as a biotransformation product of manool by microbial oxidation. While the diterpene profiles from A. chilensis tree resins can easily differentiate healthy and P. austrocedri infected individuals, the possible conversion of manool to the antifungal derivatives 4 and 6 by the microorganism remains to be established.

Urgencias Odontológicas en la Provincia de Cautín - Chile, entre los Años 2009 a 2013 / Dental Emergencies in the Cautín - Chile Province between 2009 to 2013

Las urgencias odontológicas ambulatorias comprenden un conjunto de patologías bucomaxilofaciales, de aparición súbita, de etiología múltiple, que se manifiestan principalmente por dolor agudo y que provocan una demanda espontánea de atención. El objetivo de esta investigación fue reconocer la evolución de la urgencia odontológica en los sistemas de Atención Primaria de Salud (APS) entre los años 2009 y 2013. Se realizó un estudio retrospectivo para analizar la demanda entre los años mencionados; la información se obtuvo desde los registros estadísticos mensuales de las comunas pertenecientes al Servicio de Salud Araucanía Sur (SSAS) y fueron analizados con estadística descriptiva en el programa computacional Microsoft Excel. Los resultados mostraron una tendencia a la disminución de las consultas por urgencia tanto en las garantías explicitas en salud (GES) como en las no incluidas (No GES) en los últimos años; grupos prioritarios aun son consultantes en la urgencia donde el grupo de embarazadas sufrió un aumento en las atenciones de urgencia odontológica durante los años analizados; del total de urgencias se observó una disminución de 25.000 consultas aproximadamente desde el año 2009 hasta el año 2013 con variaciones menores entre los años 2010 y 2011. Se concluye que existe una tendencia a disminuir las consultas por urgencia GES y No GES en la población analizada aunque se deben analizar las condicionantes de grupos prioritarios en la urgencia odontológica.

Dental emergencies in ambulatory system included multiple oral and maxillofacial diseases with sudden onset and different etiologies; acute pain and related conditions are associated to spontaneous admission. The aim of this research was to know the evolution of the dental emergency in the public health system related to "Primary Health Attention" (HPA) between 2009 to 2013. A retrospective research was carried out on admissions between 2009 and 2013; the information was obtained from the statistical register of "Servicio de Salud Araucanía Sur"; the data was studied by descriptive statistic with Microsoft Excel software. The results showed a tendency to decrease the consultation by dental emergency in the GES group and the No-GES group; priority groups continue to use dental emergency services and the pregnant group showed an increase in dental emergency consult during the last few years; from the total amount of consults a reduction of approximately 25,000 was observed from 2009 to 2013 with lesser variations in the 2010 and 2011 period. It is concluded that there is a tendency of fewer GES and No-GES consultations in the analyzed population and it is necessary to understand the condition of priority groups in the dental emergency.

Seasonal variation and resin composition in the Andean tree Austrocedrus chilensis.

Little is known about the changes in resin composition in South American gymnosperms associated with the different seasons of the year. The diterpene composition of 44 resin samples from seven Austrocedrus chilensis (Cupressaceae) trees, including male and female individuals, was investigated in three different seasons of the year (February, June and November). Twelve main diterpenes were isolated by chromatographic means and identified by gas chromatography-mass spectrometry and nuclear magnetic resonance (NMR). The diterpene composition was submitted to multivariate analysis to find possible associations between chemical composition and season of the year. The principal component analysis showed a clear relation between diterpene composition and season. The most characteristic compounds in resins collected in summer were Z-communic acid (9) and 12-oxo-labda-8(17),13E-dien-19 oic acid methyl ester (10) for male trees and 8(17),12,14-labdatriene (7) for female trees. For the winter samples, a clear correlation of female trees with torulosic acid (6) was observed. In spring, E-communic acid (8) and Z-communic acid (9) were correlated with female trees and 18-hydroxy isopimar-15-ene (1) with male tree resin. A comparison between percent diterpene composition and collection time showed p < 0.05 for isopimara-8(9),15-diene (2), sandaracopimaric acid (4), compound (7) and ferruginol (11).

New gastroprotective labdeneamides from (4S,9R,10R) methyl 18-carboxy-labda-8,13(E)-diene-15-oate.

Starting from the diterpene (4S,9R,10R) methyl 18-carboxy-labda-8,13(E)-dien-15-oate (PMD) and its 8(9)-en isomer [PMD 8(9)-en], 11 amides were prepared and assessed for a gastroprotective effect in the ethanol/HCl-induced gastric lesions model in mice. Basal cytotoxicity of the compounds was determined on the following human cell lines: normal lung fibroblasts (MRC-5), gastric epithelial adenocarcinoma (AGS), and hepatocellular carcinoma (Hep G2). All compounds are described for the first time. At the single oral dose of 0.1 mg/kg, compounds 1, 10, and 11 presented a strong gastroprotective effect, at least comparable with that of the reference compound lansoprazole at 1 mg/kg, reducing gastric lesions by 76.7, 67.7, and 77.2 %, respectively. The leucyl amide methyl ester 3, tryptophanyl amide methyl ester 5, and benzyl amide 6 of PMD presented a selective basal cytotoxicity on Hep G2 cells with IC50 values of 136.8, 105.3, and 94.2 µM, respectively, while the IC50 values towards AGS cells were 439.5, 928.0, and 937.3 µM, respectively. The three compounds did not affect fibroblast viability with IC50 values > 1000 µM. Compounds 7, 8, 10, and 11 showed no toxic effect against the three selected cell lines.

Resin diterpenes from Austrocedrus chilensis.

Seventeen diterpenes belonging to the labdane, abietane and isopimarane skeleton classes were isolated from the resin of the Chilean gymnosperm Austrocedrus chilensis and identified by spectroscopic and spectrometric methods. The diterpene 12-oxo-labda-8(17),13E-dien-19 oic acid is reported for the first time as a natural product and 14 diterpenes are reported for the first time for the species.