Porcine epidemic diarrhea virus strain CH/HLJ/18 isolated in China: characterization and phylogenetic analysis.

BACKGROUND: Porcine epidemic diarrhea (PED) is an infectious disease of the digestive tract caused by the porcine epidemic diarrhea virus (PEDV), characterized by vomiting, severe diarrhea, and high mortality rates in piglets. In recent years, the distribution of this disease in China has remarkably increased, and its pathogenicity has also increased. PEDV has been identified as the main cause of viral diarrhea in piglets. This study aimed to understand the genetic evolution and diversity of PEDV to provide a theoretical basis for the development of new vaccines and the prevention and treatment of PED. METHODS: A PEDV strain was isolated from the small intestine of a diarrheal piglet using Vero cells. The virus was identified using reverse transcription-polymerase chain reaction (RT-PCR), indirect immunofluorescence assay (IFA), and transmission electron microscopy. The whole genome sequence was sequenced, phylogenetic analysis was conducted using MEGA (version 7.0), and recombination analysis was performed using RDP4 and SimPlot. The S protein amino acid sequence was aligned using Cluster X (version 2.0), and the S protein was modeled using SWISS-MODEL to compare differences in structure and antigenicity. Finally, the piglets were inoculated with PEDV to evaluate its pathogenicity in newborn piglets. RESULT: PEDV strain CH/HLJ/18 was isolated. CH/HLJ/18 shared 89.4-99.2% homology with 52 reference strains of PEDV belonging to the GII-a subgroup. It was a recombinant strain of PEDV BJ-2011-1 and PEDV CH_hubei_2016 with a breakpoint located in ORF1b. Unique amino acid deletions and mutations were observed in the CH/HLJ/18 S protein. The piglets then developed severe watery diarrhea and died within 7 d of inoculation with CH/HLJ/18, suggesting that CH/HLJ/18 was highly pathogenic to newborn piglets. CONCLUSION: A highly pathogenic recombinant PEDV GII-a strain, CH/HLJ/18, was identified in China, with unique deletion and mutation of amino acids in the S protein that may lead to changes in protein structure and antigenicity. These results will be crucial for understanding the prevalence and variation of PEDV and for preventing and controlling PED.

Isolation and identification of hoylesella marshii causing pleural infection: a case report.

BACKGROUND: Hoylesella marshii can be isolated from human oral cavities affected by dental pulp and periodontal infections, as well as from the dental plaque of healthy individuals, making it a common bacterium within the oral microbiota. However, its role in causing pleural infections in humans is rare. CASE PRESENTATION: A case of purulent pleural effusion occurred shortly after discharge in an elderly patient who had undergone surgery for gastric cancer. The infection was identified as being caused by an obligate anaerobe through laboratory culture, and was further identified as Hoylesella marshii causing pleural infection through 16 S rRNA gene sequence analysis. Susceptibility testing guided precise treatment with cefoperazone-sulbactam and metronidazole. The patient's clinical symptoms improved rapidly, laboratory test indicators gradually returned to normal, and the patient ultimately recovered. CONCLUSION: Hoylesella marshii can cause pleural infections in humans. Clinical microbiology laboratories should pay special attention to the cultivation of obligate anaerobes when routine aerobic cultures do not show bacterial growth but bacteria are visible on smear staining, and when conventional identification methods fail to identify the bacterium, analysis based on the highly conserved 16 S rRNA gene sequence can accurately and specifically identify the bacterium, guiding clinicians in formulating precise anti-infection strategies.

Isolation and identification of active components from Grifola frondosa and its anti-EV71 virus effect.

BACKGROUND: It is reported that anti-enterovirus 71 (EV71) drugs have some side effects on human health. Notably, fungi plays a crucial role in promoting human health and anti-virus. Grifola frondosa is a type of large medicinal and edible fungi, rich in active substances. The present study aimed to investigate the anti-EV71 effect of G. frondosa and the potential active substances. RESULTS: In the present study, the water extract of G. frondosa was subjected to ethanol precipitation to obtain the water-extracted supernatant of G. frondosa (GFWS) and water-extracted precipitation of G. frondosa. Their inhibitory effects on EV71 virus were studied based on a cell model. The results showed that GFWS had stronger security and anti-EV71 effects. In addition, the chemical constituents of GFWS were identified by ultra-high performance liquid chromatography-tandem mass spectrometry, which were selected for further separation and purification. Three compounds, N-butylaniline, succinic acid and l-tryptophan, were isolated from GFWS by NMR spectroscopy. It is noteworthy that N-butylaniline and l-tryptophan were isolated and identified from the G. frondosa fruiting bodies for the first time. Our study found that l-tryptophan has anti-EV71 virus activity, which reduced EV71-induced apoptosis and significantly inhibited the replication process after virus adsorption. Furthermore, it could also bind to capsid protein VP1 to prevent the virus from attaching to the cells. CONCLUSION: l-tryptophan was an inhibitor of the EV71 virus, which could be used in infant nutrition and possibly provide a new drug to treat hand, foot and mouth disease. © 2024 Society of Chemical Industry.

[Chemical constituents from Alangium chinense subsp. pauciflorum].

Chemical constituents of 70% ethanol extract of Alangium chinense subsp. pauciflorum were investigated. The 70% ethanol extract of A. chinense subsp. pauciflorum was isolated and purified by D-101 macroporous resins, silica gel, Sephadex LH-20 and other methods. As a result, nineteen compounds were isolated and identified as 4-cyclohexene-1α,2α,3α-triol-1-O-ß-D-glucoside(1), 1ß,4α,6α,13-tetrahydroxy-eudesm-11(12)-ene(2), sucrose(3), 1'-O-benzyl-α-L-rhamnopyranosyl-(1″→6')-ß-D-glucopyranoside(4), bis(2-ethylhexyl)benzene-1,2-dicarboxylate(5),(Z)-10-heneicosenoic acid(6), di-O-methylcrenati(7), methyl-α-D-fructofuranoside(8), ß-daucosterol(9), syringic acid(10), vanillicacid(11), octacosanol(12), isoarborinol(13), 2,7-dihydroxy-6-methyl-4-(1-methylethyl)-1-naphthalenecarboxylate(14),vanillin(15), coniferyl aldehyde(16), 9(11)-dehydroergosterolperoxide(17), 5α,8α-epidioxy-(22E,24R)-ergosta-6,22-dien-3ß-ol(18), ß-sitosterol(19), respectively. Compounds 1 and 2 were new compounds, compounds 5-11, 13, 15-18 were isolated from Alangium for the first time.The anti-inflammatory activity of compourd 1 was determinded by the LPS-induced RAW264.7 macrophage inflammation model. The results showed that the new compound 1 has a certain inhibitory effect on LPS-induced NO production of RAW264.7 cells, and the inhibitory rate was 54.57%.

[Active constituents of essential oil from Curcuma phaeocaulis for treatment of dysmenorrhea].

This study aims to identify the active constituents of essential oil from the rhizomes of Curcuma phaeocaulis for the treatment of dysmenorrhea. The compounds were separated and purified by molecular distillation, silica gel and Sephadex LH-20 column chromatography, preparative thin layer chromatography, and semi-preparative high performance liquid chromatography. Their structures were identified by mass spectrometry and nuclear magnetic resonance spectroscopy. The animal model of primary dysmenorrhea and the contraction model of isolated uterine smooth muscle of rats were established to examine the active constituents in the essential oil for treating dysmenorrhea. Six sesquiterpenes were isolated and identified as dehydrocommiterpene A(1), comosone Ⅱ(2), 5α(H)-eudesma-3(4),7(11)-dien-9ß-ol-6-one(3), guaia-6(7)-en-11-ol(4), curcumenol(5), and isocurcumenol(6), among which compound 1 was a novel compound. The animal experiments showed that the essential oil from C. phaeocaulis significantly lowered the level of PGF_(2α) in uterine tissue compared with the model group. The experiment with the contraction model of isolated uterine smooth muscle demonstrated that the components with high boiling points outperformed those with low boiling points in relaxing the uterine smooth muscle, and compounds 1, 2, 5, and 6 isolated from the fraction with a high boiling point had the effect of relaxing the uterine smooth muscle. Among them, compounds 5 and 6 inhibited the extracellular Ca~(2+) influx and intracellular Ca~(2+) release to relax the uterine smooth muscle. In conclusion, the components with high boiling points and sesquiterpenes are the active components in the essential oil of C. phaeocaulis for treating dysmenorrhea.

[Chemical constituents of Helleborus thibetanus].

The chemical constituents of Helleborus thibetanus were isolated and purified by silica gel column chromatography, Sephadex LH-20 gel column chromatography, and semi-preparative RP-HPLC, and the structures of all compounds were identified by modern spectrographic technology(MS, NMR). The MTT method was used to measure the cytotoxicity of compounds 1-8. Twelve compounds were isolated from the roots and rhizomes of H. thibetanus and were identified as(25R)-22ß,25-expoxy-26-[(O-ß-D-glucopyranosyl)oxy]-1ß,3ß-dihydroxyfurosta-5-en(1), ß-sitosterol myristate(2), ß-sitosterol lactate(3), ß-sitosterol 3-O-ß-D-glucopyrannoside(4), 4,6,8-trihydroxy-3,4-dihydronaphthalen-1(2H)-one(5), 1,3,5-trimethoxybenzene(6), 7,8-dimethylbenzo pteridine-2,4(1H,3H)-dione(7), 1H-indole-3-carboxylic acid(8), p-hydroxy cinnamic acid(9), lauric acid(10), n-butyl α-L-arabinofuranoside(11) and methyl-α-D-fructofuranoside(12), respectively. Among them, compound 1 is a new compound and named thibetanoside L; compounds 2, 5-8, 11 are first isolated from the family Ranunculaceae; compound 12 is isolated from the genus Helleborus for the first time. The results of MTT assay showed that the IC_(50) values of compounds 1-8 against HepG2 and HCT116 cells were greater than 100 µmol·L~(-1).

Three rare anti-inflammatory sesquiterpene lactones from Magnolia grandiflora.

Four new sesquiterpene lactones (SLs) (1-4), along with a biosynthetically related SL (5), have been isolated from the leaves of Magnolia grandiflora. Magrandate A (1) is notable as the first C18 homogemarane type SL, featuring a unique 1,7-dioxaspiro[4.4]nonan-6-one core. Compounds 2 and 3, representing the first instances of chlorine-substituted gemarane-type SL analogs in natural products, were also identified. The structures of these isolates were elucidated through a combination of spectroscopic data analysis, electronic circular dichroism calculations, and X-ray single-crystal diffraction analysis. All isolates demonstrated anti-inflammatory activity in lipopolysaccharide-stimulated RAW264.7 cells. Notably, 3-5 showed a significant inhibitory effect on nitric oxide production, with IC50 values ranging from 0.79 to 4.73 µmol·L-1. Additionally, 4 and 5 exhibited moderate cytotoxic activities against three cancer cell lines, with IC50 values between 3.09 and 11.23 µmol·L-1.

Prevalence, Molecular Characteristics and Virulence Identification of Bovine Parainfluenza Virus Type 3 in China.

Bovine parainfluenza virus type 3 (BPIV-3) is one of the major pathogens of the bovine respiratory disease complex (BRDC). BPIV-3 surveillance in China has been quite limited. In this study, we used PCR to test 302 cattle in China, and found that the positive rate was 4.64% and the herd-level positive rate was 13.16%. Six BPIV-3C strains were isolated and confirmed by electron microscopy, and their titers were determined. Three were sequenced by next-generation sequencing (NGS). Phylogenetic analyses showed that all isolates were most closely related to strain NX49 from Ningxia; the genetic diversity of genotype C strains was lower than strains of genotypes A and B; the HN, P, and N genes were more suitable for genotyping and evolutionary analyses of BPIV-3. Protein variation analyses showed that all isolates had mutations at amino acid sites in the proteins HN, M, F, and L. Genetic recombination analyses provided evidence for homologous recombination of BPIV-3 of bovine origin. The virulence experiment indicated that strain Hubei-03 had the highest pathogenicity and could be used as a vaccine candidate. These findings apply an important basis for the precise control of BPIV-3 in China.

Isolation and Identification of Postharvest Rot Pathogens in Citrus × tangelo and Their Potential Inhibition with Acidic Electrolyzed Water.

This study focused on the identification of rot-causing fungi in Citrus × tangelo (tangelo) with a particular emphasis on investigating the inhibitory effects of acidic electrolyzed water on the identified pathogens. The dominant strains responsible for postharvest decay were isolated from infected tangelo fruits and characterized through morphological observation, molecular identification, and pathogenicity detection. Two strains were isolated from postharvest diseased tangelo fruits, cultured and morphologically characterized, and had their gene fragments amplified using primers ITS1 and ITS4. The results revealed the rDNA-ITS sequence of two dominant pathogens were 100% homologous with those of Penicillium citrinum and Aspergillus sydowii. These isolated fungi were confirmed to induce tangelo disease, and subsequent re-isolation validated their consistency with the inoculum. Antifungal tests demonstrated that acidic electrolyzed water (AEW) exhibited a potent inhibitory effect on P. citrinum and A. sydowii, with EC50 values of 85.4 µg/mL and 60.12 µg/mL, respectively. The inhibition zones of 150 µg/mL AEW to 2 kinds of pathogenic fungi were over 75 mm in diameter. Furthermore, treatment with AEW resulted in morphological changes such as bending and shrinking of the fungal hyphae surface. In addition, extracellular pH, conductivity, and absorbance at 260 nm of the fungi hypha significantly increased post-treatment with AEW. Pathogenic morphology and IST sequencing analysis confirmed P. citrinum and A. sydowii as the primary pathogenic fungi, with their growth effectively inhibited by AEW.

High-throughput sequencing and characterization of potentially pathogenic fungi from the vaginal mycobiome of giant panda (Ailuropoda melanoleuca) in estrus and non-estrus.

Introduction: The giant panda (Ailuropoda melanoleuca) reproduction is of worldwide attention, and the vaginal microbiome is one of the most important factors affecting the reproductive rate of giant pandas. The aim of this study is to investigate the diversity of vaginal mycobiota structure, and potential pathogenic fungi in female giant pandas during estrus and non-estrus. Methods: This study combined with high-throughput sequencing and laboratory testing to compare the diversity of the vaginal mycobiota in giant pandas during estrus and non-estrus, and to investigate the presence of potentially pathogenic fungi. Potentially pathogenic fungi were studied in mice to explore their pathogenicity. Results and discussion: The results revealed that during estrus, the vaginal secretions of giant pandas play a crucial role in fungal colonization. Moreover, the diversity of the vaginal mycobiota is reduced and specificity is enhanced. The abundance of Trichosporon and Cutaneotrichosporon in the vaginal mycobiota of giant pandas during estrus was significantly higher than that during non-estrus periods. Apiotrichum and Cutaneotrichosporon were considered the most important genera, and they primarily originate from the environment owing to marking behavior exhibited during the estrous period of giant pandas. Trichosporon is considered a resident mycobiota of the vagina and is an important pathogen that causes infection when immune system is suppressed. Potentially pathogenic fungi were further isolated and identified from the vaginal secretions of giant pandas during estrus, and seven strains of Apiotrichum (A. brassicae), one strain of Cutaneotrichosporon (C. moniliiforme), and nine strains of Trichosporon (two strains of T. asteroides, one strain of T. inkin, one strain of T. insectorum, and five strains of T. japonicum) were identified. Pathogenicity results showed that T. asteroides was the most pathogenic strain, as it is associated with extensive connective tissue replacement and inflammatory cell infiltration in both liver and kidney tissues. The results of this study improve our understanding of the diversity of the vaginal fungi present in giant pandas and will significantly contribute to improving the reproductive health of giant pandas in the future.

Isolation of Epizootic Hemorrhagic Disease Virus Serotype 10 from Culicoides tainanus and Associated Infections in Livestock in Yunnan, China.

Two strains of viruses, JC13C644 and JC13C673, were isolated from Culicoides tainanus collected in Jiangcheng County, Yunnan Province, situated along the border area shared by China, Laos, and Vietnam. JC13C644 and JC13C673 viruses can cause cytopathic effect (CPE) in mammalian cells BHK21 and Vero cells, and cause morbidity and mortality in suckling mice 48 h after intracerebral inoculation. Whole-genome sequencing was performed, yielding complete sequences for all 10 segments from Seg-1 (3942nt) to Seg-10 (810nt). Phylogenetic analysis of the sub-core-shell (T2) showed that the JC13C644 and JC13C673 viruses clustered with the Epizootic Hemorrhagic Disease Virus (EHDV) isolated from Japan and Australia, with nucleotide and amino acid homology of 93.1% to 98.3% and 99.2% to 99.6%, respectively, suggesting that they were Eastern group EHDV. The phylogenetic analysis of outer capsid protein (OC1) and outer capsid protein (OC2) showed that the JC13C644 and JC13C673 viruses were clustered with the EHDV-10 isolated from Japan in 1998, with the nucleotide homology of 98.3% and 98.5%, and the amino acid homology of 99.6% and 99.6-99.8%, respectively, indicating that they belong to the EHDV-10. Seroepidemiological survey results demonstrated that JC13C644 virus-neutralizing antibodies were present in 29.02% (177/610) of locally collected cattle serum and 11.32% (89/786) of goat serum, implying the virus's presence in Jiangcheng, Yunnan Province. This finding suggests that EHDV-10 circulates not only among blood-sucking insects in nature but also infects local domestic animals in China. Notably, this marks the first-ever isolation of the virus in China and its discovery outside of Japan since its initial isolation from Japanese cattle. In light of these results, it is evident that EHDV Serotype 10 exists beyond Japan, notably in the natural vectors of southern Eurasia, with the capacity to infect local cattle and goats. Therefore, it is imperative to intensify the surveillance of EHDV infection in domestic animals, particularly focusing on the detection and monitoring of new virus serotypes that may emerge in the region and pose risks to animal health.

Carvacrol Treatment Reduces Decay and Maintains the Postharvest Quality of Red Grape Fruits (Vitis vinifera L.) Inoculated with Alternaria alternata.

In this study, we isolated and identified pathogenic fungi from the naturally occurring fruits of red grapes, studied their biological characteristics, screened fifteen essential oil components to find the best natural antibacterial agent with the strongest inhibitory effect, and then compared the incidence of postharvest diseases and storage potential of red grapes treated with two concentrations (0.5 EC50/EC50) of essential oil components (inoculated with pathogenic fungi) during storage for 12 d at room temperature. In our research, Alternaria alternata was the primary pathogenic fungus of red grapes. Specifically, red grapes became infected which caused diseases, regardless of whether they were inoculated with Alternaria alternata in an injured or uninjured state. Our findings demonstrated that the following conditions were ideal for Alternaria alternata mycelial development and spore germination: BSA medium, D-maltose, ammonium nitrate, 28 °C, pH 6, and exposure to light. For the best Alternaria alternata spore production, OA medium, mannitol, urea, 34 °C, pH 9, and dark conditions were advised. Furthermore, with an EC50 value of 36.71 µg/mL, carvacrol demonstrated the highest inhibitory impact on Alternaria alternata among the 15 components of essential oils. In the meantime, treatment with EC50 concentration of carvacrol was found to be more effective than 0.5 EC50 concentration for controlling Alternaria alternata-induced decay disease of red grapes. The fruits exhibited remarkable improvements in the activity of defense-related enzymes, preservation of the greatest hardness and total soluble solids content, reduction in membrane lipid peroxidation in the peel, and preservation of the structural integrity of peel cells. Consequently, carvacrol was able to prevent the Alternaria alternata infestation disease that affects red grapes, and its EC50 concentration produced the greatest outcomes.

Secondary Metabolites from Streptomyces sp CSDX076 for the First Time / Metabolitos secundarios de Streptomyces SP CSDX076 por primera vez

ABSTRACT Objective: To investigate the secondary metabolites from the cultures of Streptomyces sp CSDX076. Methods: The compounds were isolated using column chromatography and RP-18 medium-pressure liquid chromatography. Their structures were elucidated by one-dimensional and two-dimensional nuclear magnetic resonance spectroscopic methods in combination with mass spectrometry experiments. Results: Four compounds were isolated from the cultures of Streptomyces sp CSDX076 and identified as aurantiamide benzoate, deoxytryptoquivaline, 2-acetyl-3,5-dihydroxyl-benzene acetic acid, and 2-acetyl-3,5-dihydroxyl-benzene ester. Conclusion: It was the first time that the four isolated compounds were obtained from the Streptomyces genus.

RESUMEN Objetivo: Investigar los metabolitos secundarios de los cultivos de Streptomyces sp CSDX076. Métodos: Los compuestos fueron aislados usando la cromatografía de columna y cromatografía líquida RP-18 de presión media. Sus estructuras fueron dilucidadas mediante métodos espectroscópicos de resonancia magnética nuclear unidimensional y bidimensional, combinados con experimentos de espectrometría de masa. Resultados: Cuatro compuestos de culturas de Streptomyces sp CSDX076 fueron aislados e identificados como benzoato de aurantiamida, deoxitriptoquivalina, ácido acético 2-acetil-3,5-dihidroxil-benzeno, y éster 2-acetil-3,5-dihidroxil-benzeno. Conclusión: Fue la primera vez que los cuatro compuestos aislados se obtuvieron del género Streptomyces.

Phenol degradation and genotypic analysis of dioxygenase genes in bacteria isolated from sediments

Abstract The aerobic degradation of aromatic compounds by bacteria is performed by dioxygenases. To show some characteristic patterns of the dioxygenase genotype and its degradation specificities, twenty-nine gram-negative bacterial cultures were obtained from sediment contaminated with phenolic compounds in Wuhan, China. The isolates were phylogenetically diverse and belonged to 10 genera. All 29 gram-negative bacteria were able to utilize phenol, m-dihydroxybenzene and 2-hydroxybenzoic acid as the sole carbon sources, and members of the three primary genera Pseudomonas, Acinetobacter and Alcaligenes were able to grow in the presence of multiple monoaromatic compounds. PCR and DNA sequence analysis were used to detect dioxygenase genes coding for catechol 1,2-dioxygenase, catechol 2,3-dioxygenase and protocatechuate 3,4-dioxygenase. The results showed that there are 4 genotypes; most strains are either PNP (catechol 1,2-dioxygenase gene is positive, catechol 2,3-dioxygenase gene is negative, protocatechuate 3,4-dioxygenase gene is positive) or PNN (catechol 1,2-dioxygenase gene is positive, catechol 2,3-dioxygenase gene is negative, protocatechuate 3,4-dioxygenase gene is negative). The strains with two dioxygenase genes can usually grow on many more aromatic compounds than strains with one dioxygenase gene. Degradation experiments using a mixed culture representing four bacterial genotypes resulted in the rapid degradation of phenol. Determinations of substrate utilization and phenol degradation revealed their affiliations through dioxygenase genotype data.

Caracterización de especies de Malassezia en piel sana de estudiantes de secundaria / Characterization of Malassezia Species on the Healthy Skin of High School Students

El género Malassezia comprende un grupo de levaduras lipofílicas que forman parte de la microbiota de la piel del hombre y otros vertebrados. Sin embargo se han relacionado con varias entidades dermatológicas. En esta investigación se planteó como objetivo caracterizar las especies de Malassezia aisladas en piel sana de estudiantes del Liceo Baralt de la Ciudad de Maracaibo- Edo. Zulia. Las muestras fueron tomadas, mediante el método de la impronta con cinta adhesiva transparente, de cuero cabelludo, pabellón auricular, pecho y espalda e inoculadas en el medio Dixon Agar modificado e incubadas a 32°C por 14 días. La identificación de las especies se realizó siguiendo las claves descritas por Gueho y Cols. y el test de difusión en tween propuesto por Guillot y Cols, la prueba de la catalasa y la utilización de triptófano como única fuente de carbono. De un total de 100 estudiantes evaluados 81(81%) fueron positivos a Malassezia, se obtuvo 184 aislamientos, 100 (54,30%) para el sexo masculino y 84 (45,6%) para el femenino. Los resultados muestran una alta prevalencia de Malassezia furfur (54,3%) seguida de Malassezia sympodialis (45,1%) y Malassezia globosa (0,50%). Las localizaciones anatómicas con mayor número de aislamientos fueron espalda (33%) y pecho (30,2%).

The genus Malassezia includes a group of lipophilic yeasts that form part of the microbiota of the skin of humans and other vertebrates. Nevertheless, they have been related to several dermatological entities. This research proposed to characterize the morfo-physiological Malassezia species isolated on the healthy skin of students at the Baralt High School in the city of Maracaibo, State of Zulia. Samples were taken using the imprint method with adhesive transparent tape on the scalp, pinna, chest and back, inoculated into a modified Dixon Agar medium and incubated at 32°C for 14 days. Identification of the species was carried out following the keys described by Gueho and Cols, the diffusion in tween test proposed by Guillot and collaborators, the catalase test and the utilization of triptophan as the only source of carbon. Out of a total of 100 evaluated students, 81 (81%) were positive for Malassezia and 184 isolations were obtained; 100 (54.30%) were of the masculine sex and 81 (45.6%) were females. The results show a high prevalence of Malassezia furfur (54.3%) followed by Malassezia sympodialis (45.1%) and finally, Malassezia globosa (0.50%). Anatomical locations with the greatest number of isolations were the back (33%) and chest (30.2%).

Aislamiento e identificación de especies del género Malassezia en piel sana de niños desnutridos y eutróficos de multihogares de cuidado diario / Isolation and identification of Malassezia species isolated of healthy skin of malnourished and eutrophic children attended in day care centers in Venezuela

El género Malassezia comprende un grupo de levaduras lipofílicas, integrantes de la microbiota normal de la piel del hombre y de animales. Se estudió la presencia de especies de Malassezia en piel sana de niños, que asistían a multihogares de cuidado diario de la ciudad de Maracaibo, estado Zulia, Venezuela. La evaluación antropométrica permitió el diagnóstico de niños desnutridos (n = 48) y eutróficos (n = 40). Estos niños, entre 1 y 6 años de edad, que no presentaban lesiones en la piel, se seleccionaron para el estudio. Las muestras de la piel se tomaron de distintas regiones anatómicas. Se empleó el método de la impronta con cinta plástica transparente. Se realizó un examen directo con azul de metileno (0,25%) y se cultivó en el medio Dixon con antibiótico. La identificación de los aislados se hizo según la metodología clásica. Los resultados indican que los niños desnutridos y eutróficos presentaron una colonización por Malassezia en un elevado porcentaje (66,6% y 65,0%, respectivamente). Se observó en los desnutridos un predominio significativo de M. furfur (77,0%). Esta especie se aisló en todas las localizaciones, tanto en los desnutridos como en los eutróficos, mientras que M. slooffiae predominó en la espalda en los eutróficos. Por otra parte, se observó en los desnutridos un predominio significativo de M. furfur en el sexo masculino y en los eutróficos en el femenino. Esta investigación demostró el predominio de M. furfur en piel sana de niños desnutridos y eutróficos.

The Malassezia genus contains a group of lipophilic yeasts that form part of the normal microbiota of human and animals skins. The presence of Malassezia species was studied on healthy skin in children, who attended day care centers, located in Maracaibo, Zulia state, Venezuela. Children without skin lesions that were anthropometrically classified as malnourished (48) and eutrophics (40), were studied. Samples were taken from different anatomic regions with a transparent plastic tape. The direct examination was done using blue methylene (0.25%) and then, samples were cultivated in Dixon medium with antibiotic. The identification of the isolated yeasts was done by classical methodology. The results obtained indicate that malnourished and eutrophics children were positive to Malassezia in relatively high prevalences (66.6% and 65.0% respectively). It is worthy of notice that M. furfur was predominantly present in malnourished children (77%). It was isolated from all the anatomic locations in both groups of children. M. slooffiae was mainly located in the back of the eutrophic children. M. furfur was isolated preferently in malnourished male children, while in the eutrophic children, it was observed in females. It was demonstrated that M. furfur was predominantly present in the healthy skin of malnourished and eutrophic children.