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1.
Microorganisms ; 7(12)2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31861143

RESUMO

Micromycetes from unexplored sources represent an opportunity to discover novel natural products to control insect pests. With this aim, a strain of Acremonium masseei CICY026 isolated from a tropical sinkhole was identified, cultured on fermented rice, and its ethyl acetate extract (EAE) was evaluated against three serious phytophagous insects (Bemisia tabaci, Myzus persicae, and Rhopalosiphum padi). DNA from A. masseei CICY026 was used to confirm its identity. EAE caused settling inhibition (SI) of M. persicae and R. padi (67.5% and 75.3%, respectively). Bioassay-guided fractionation of the active EAE led to the isolation of a novel metabolite, named hexahydroacremonintriol (1), and of acremonin A glucoside (2). The structures of 1 and 2 were determined using IR, one- and two-dimensional NMR, HRMS, and confirmed by theoretical data. The aphid M. persicae was noticeably sensitive to 1 and 2 (SI: 55.6% and 67.2%, respectively), whereas R. padi was only slightly affected by 1 (SI: 59%). This new knowledge about mycobiota from these special sinkhole ecosystems will inform the development of new biorational pesticides.

2.
Rev. colomb. cienc. pecu ; 31(3): 196-203, jul.-set. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-978259

RESUMO

Abstract Background: Genetic variability of populations is essential for their genetic conservation and improvement, and genealogy analysis is a useful tool to estimate it. Objective: To determine genetic variability and inbreeding levels in Tropical Milking Criollo (LT). Methods: This study analyzed the genealogy of LT using the ENDOG software. Registration certificates of 3,427 LT animals born between 1945 and 2013, and from 608 born between 1950 and 2013 were used. Two populations were defined: the first one with all registered animals (PLT), and the second with nucleus animals (PCP). Results: Estimates for PLT and PCP were: founders 890, 114; ancestors 855, 102; effective founders 111, 43; effective ancestors 72, 26, and effective population size 68.1 and 64.6, respectively. Inbreeding coefficients were 4.32 and 3.48% for the highest genetic integrity index; and the average relatedness (AR) coefficients were 1.19 and 5.55 for PLT and PCP, respectively. Genealogy depth was shallow in both populations, with full equivalent generations of 2.00 and 3.53. Global generation intervals were about seven years. Conclusions: The LT population is not endangered and its genetic improvement program should continue.


Resumen Antecedentes: la variabilidad genética de las poblaciones es esencial para su conservación y mejora genética, y el análisis de genealogía es útil para estimarla. Objetivo: determinar la variabilidad genética y los niveles de consanguinidad en la raza criolla Lechero Tropical (LT). Métodos: el estudio analizó la genealogía de la raza criolla LT con el programa ENDOG v4.8. Se utilizaron 3.427 registros de animales LT nacidos entre 1945 y 2013, y de 608 nacidos entre 1950 y 2013. Se definieron dos poblaciones, una que incluye todos los animales registrados (PLT) y otra solamente con los animales provenientes del núcleo genético (PCP). Resultados: en la PLT y PCP se estimaron animales fundadores 890, 114; ancestros 855, 102; número efectivo de fundadores 111, 43; número efectivo de ancestros 72, 26, y tamaño efectivo de población 68,1, 64,6, respectivamente. Para la categoría más alta de índice de integridad genética, los coeficientes de consanguinidad fueron 4,32 y 3,48%; y el coeficiente medio de relación global (AR) fue 1,19 y 5,55 para PLT y PCP, respectivamente. La profundidad de la genealogía en ambas poblaciones fue superficial con generaciones completas equivalentes de 2,00 y 3,53. Los intervalos generacionales globales fueron cercanos a siete años. Conclusiones: la población LT no se encuentra en riesgo de extinción y puede continuar con su programa de mejora genética.


Resumo Antecedentes: a variabilidade genética das populações é essencial para sua conservação e melhora genética e a análise da genealogia é útil para estimá-la. Objetivo: determinar a variabilidade genética e os níveis de consanguinidade na raça crioula Leiteiro Tropical (LT). Métodos: o estudo analisou a genealogia da raça crioula LT com o programa ENDOG v4.8. Foram utilizaram 3.427 registros de animais LT nascidos de 1945 a 2013, e de 608 nascidos entre 1950 e 2013. Foram definidas duas populações, uma que inclui todos os animais registrados (PLT) e outra somente com os animais provenientes do núcleo genético (PCP). Resultados: na PLT e PCP foram estimados animais fundadores 890, 114; ascendentes 855, 102; número efetivo de fundadores 111, 43; número efetivo de ascendentes 72, 26 e tamanho efetivo da população 68,1, 64.6, respectivamente. Para a categoria mais alta de índice de integridade genética os coeficientes de consanguinidade foram 4,32 e 3,48%; o coeficiente médio da relação global (AR) foi 1,19 e 5,55 para PLT e PCP, respectivamente. A profundidade da genealogia em ambas populações foi superficial com gerações completas equivalentes de 2,00 e 3,53. Os intervalos geracionais globais foram próximos a sete anos. Conclusões: a população LT não se encontra em risco de extinção e pode continuar com seu programa de melhoria genética.

3.
Rev Argent Microbiol ; 49(1): 83-92, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28258772

RESUMO

Fungal metabolites are promising alternatives for the development of biorational pesticides. In this sense, microfungi from tropical regions are valuable sources of natural compounds for pest management. With the aim of broadening the search for new eco-friendly products to manage plant pests, this study was carried out to evaluate the biological activity of 23 tropical fungal extracts on three species of phytophagous insects and a plant parasitic nematode. In addition, the active principles of the most effective extract were identified. The insect deterrent activity of fungal extracts was evaluated on the settling of aphids Myzus persicae and Rhopalosiphum padi, and on the feeding of lepidoptera larva Spodoptera littoralis; the nematostatic activity was evaluated on the mobility of Meloidogyne javanica. Active metabolites from Gliomastix masseei were identified by GC-MS techniques and by comparison with commercial standards. Results showed seven extracts with strong effect on the settling of M. persicae and R. padi (settling inhibition >80%). The calculated median of effective concentration (EC50) values ranged from 8 to 38µg/cm2 for the extracts of Clonostachys rosea and G. masseei, respectively. Bioassay-guided separation of the ethyl acetate extract of G. masseei revealed the presence of fatty acids and their derivatives, where methyl 9-octadecenoate was the most active compound with EC50 values of 16µg and 35µg/cm2 for M. persicae and R. padi, respectively. Extracts of C. rosea and G. masseei could be a promising option in the control of pest aphids in agriculture.


Assuntos
Agentes de Controle Biológico , Fungos , Insetos , Animais , Afídeos , Fungos/química , Larva , México , Plantas
4.
Rev. argent. microbiol ; 49(1): 83-92, mar. 2017. tab
Artigo em Inglês | LILACS | ID: biblio-843187

RESUMO

Fungal metabolites are promising alternatives for the development of biorational pesticides. In this sense, microfungi from tropical regions are valuable sources of natural compounds for pest management. With the aim of broadening the search for new eco-friendly products to manage plant pests, this study was carried out to evaluate the biological activity of 23 tropical fungal extracts on three species of phytophagous insects and a plant parasitic nematode. In addition, the active principles of the most effective extract were identified. The insect deterrent activity of fungal extracts was evaluated on the settling of aphids Myzus persicae and Rhopalosiphum padi, and on the feeding of lepidoptera larva Spodoptera littoralis; the nematostatic activity was evaluated on the mobility of Meloidogyne javanica. Active metabolites from Gliomastix masseei were identified by GC-MS techniques and by comparison with commercial standards. Results showed seven extracts with strong effect on the settling of M. persicae and R. padi (settling inhibition >80%). The calculated median of effective concentration (EC50) values ranged from 8 to 38 µg/cm² for the extracts of Clonostachys rosea and G. masseei, respectively. Bioassay-guided separation of the ethyl acetate extract of G. masseei revealed the presence of fatty acids and their derivatives, where methyl 9-octadecenoate was the most active compound with EC50 values of 16 µg and 35 µg/cm² for M. persicae and R. padi, respectively. Extracts of C. rosea and G. masseei could be a promising option in the control of pest aphids in agriculture.


Los metabolitos fúngicos son agentes prometedores para el desarrollo de plaguicidas biorracionales. En este sentido, los hongos microscópicos de zonas tropicales representan una valiosa fuente de compuestos naturales para el manejo de plagas. Con la finalidad de ampliar la investigación en productos amigables con el medio ambiente, en este estudio se evaluó la actividad biológica de 23 extractos de hongos sobre 3 especies de insectos fitófagos y un nematodo fitoparásito; además se identificaron los componentes del extracto más activo. El efecto disuasivo de los extractos fúngicos se evaluó en el asentamiento de Myzus persicae y Rhopalosiphum padi, así como en la alimentación de Spodoptera littoralis; la actividad nematostática se evaluó sobre la movilidad de Meloidogyne javanica. Los metabolitos activos de Gliomastix masseei se identificaron por cromatografía de gases-espectrometría de masas y por comparación con muestras comerciales. Los resultados mostraron 7 extractos con fuerte efecto en la inhibición del asentamiento (> 80%) de M. persicae y R. padi. Los valores de la concentración efectiva media (CE50) estuvieron en el rango de 8 a 38 µg/cm² para los extractos de Clonostachys rosea y G. masseei, respectivamente. El extracto de acetato de etilo de G. masseei se fraccionó por un proceso biodirigido y reveló la presencia de ácidos grasos y sus derivados, donde el 9-octadecenoato de metilo fue el más activo, con una CE50 de 16 µg/cm² para M. persicae y 35 µg/cm² para R. padi. Los extractos fúngicos de C. rosea y G. masseei pueden ser una alternativa promisoria en el control de áfidos que son plaga en la agricultura.


Assuntos
Animais , Agentes de Controle Biológico , Fungos , Insetos , Afídeos , Plantas , Fungos/química , Larva , México
5.
BMC Gastroenterol ; 13: 95, 2013 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-23710610

RESUMO

BACKGROUND: Intussusception (IS) is a form of acute intestinal obstruction that occurs mainly in infants and is usually of unknown cause. An association between IS and the first licensed rotavirus vaccine, a reassortant-tetravalent, rhesus-based rotavirus vaccine (RRV-TV), led to the withdrawal of the vaccine. New rotavirus vaccines have now been developed and extensively studied for their potential association with IS. This study aimed to describe the epidemiology and to estimate the incidence of IS in Latin American infants prior to new vaccine introduction. METHODS: Children under 2 years of age representing potential IS cases were enrolled in 16 centers in 11 Latin American countries from January 2003 to May 2005. IS cases were classified as definite, probable, possible or suspected as stated on the Brighton Collaboration Working Group guidelines. RESULTS: From 517 potential cases identified, 476 (92%) cases were classified as definite, 21 probable, 10 possible and 10 suspected for intussusception. Among the 476 definite IS cases, the median age at presentation was 6.4 months with 89% of cases aged <1 year. The male to female ratio was 1.5:1. The incidence of definite IS per 100,000 subject-years ranged from 1.9 in Brazil to 62.4 in Argentina for children <2 years of age, and from 3.8 in Brazil to 105.3 in Argentina for children aged <1 year. Median hospital stay was 4 days with a high prevalence of surgery as the primary treatment (65%). Most cases (88%) made a complete recovery, but 13 (3%) died. No clear seasonal pattern of IS cases emerged. CONCLUSIONS: This study describes the epidemiology and estimates the incidence of IS in Latin American infants prior to the introduction of new rotavirus vaccines. The incidence of IS was found to vary between different countries, as observed in previous studies. TRIAL REGISTRATION: Clinical study identifier 999910/204 (SERO-EPI-IS-204).


Assuntos
Intussuscepção/epidemiologia , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Incidência , Lactente , Intussuscepção/cirurgia , América Latina/epidemiologia , Masculino , Estudos Prospectivos , Vacinas contra Rotavirus
6.
Bioorg Med Chem ; 16(9): 5232-46, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18356059

RESUMO

Total syntheses of (+/-)-ovalicin, its C4(S( *))-isomer 44, and C5-side chain intermediate 46 were accomplished via an intramolecular Heck reaction of (Z)-3-(tert-butyldimethylsilyloxy)-1-iodo-1,6-heptadiene and a catalytic amount of palladium acetate. Subsequent epoxidation, dihydroxylation, methylation, and oxidation led to (3S( *),5R( *),6R( *))-5-methoxy-6-(tert-butyldimethylsilyloxy)-1-oxaspiro[2.5]octan-4-one (2), a reported intermediate. The addition of a side chain with cis-1-lithio-1,5-dimethyl-1,4-hexadiene (27) followed by oxidation afforded (+/-)-ovalicin. The functional group manipulation afforded a number of regio- and stereoisomers, which allow the synthesis of analogs for bioevaluation. The structure of 44 was firmly established via a single-crystal X-ray analysis. The stereochemistry at C4 generated from the addition reactions of alkenyllithium with ketones 2, 40, and 45 is dictated by C6-alkoxy functionality. Anti-trypanosomal activities of various ovalicin analogs and synthetic intermediates were evaluated, and C5-side chain analog, 46, shows the strongest activity. Compound 44 shows antiproliferative effect against HL-60 tumor cells in vitro. Compounds 46 and a precursor, (3S( *),4R( *),5R( *),6R( *))-5-methoxy-4-[(E)-(1',5'-dimethylhexa-1',4'-dienyl)]-6-(tert-butyldimethylsilyloxy)-1-oxaspiro[2.5]octan-4-ol (28), may be explored for the development of anti-parasitic drugs.


Assuntos
Antiprotozoários/síntese química , Antiprotozoários/farmacologia , Sesquiterpenos/síntese química , Sesquiterpenos/farmacologia , Trypanosoma brucei brucei/efeitos dos fármacos , Animais , Antiprotozoários/química , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Compostos de Epóxi/síntese química , Compostos de Epóxi/química , Compostos de Epóxi/farmacologia , Células HL-60 , Humanos , Hidroxilação , Metilação , Modelos Moleculares , Estrutura Molecular , Oxirredução , Testes de Sensibilidade Parasitária , Sesquiterpenos/química , Estereoisomerismo , Relação Estrutura-Atividade
7.
Hum Genet ; 111(3): 278-83, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12215841

RESUMO

True hermaphroditism (TH) is an unusual form of sex reversal, characterized by the development of testicular and ovarian tissue in the same subject. Approximately 60% of the patients have a 46,XX karyotype, 33% are mosaics with a second cell line containing a Y chromosome, while the remaining 7% are 46,XY. Molecular analyses have demonstrated that SRY is present in only 10% of TH with a 46,XX karyotype; therefore, in the remaining 90%, mutations at unknown X-linked or autosomal sex determining loci have been proposed as factors responsible for testicular development. True hermaphroditism presents considerable genetic heterogeneity with several molecular anomalies leading to the dual gonadal development as SRY point mutations or SRY hidden gonadal mosaicism. In order to identify genetic defects associated with subjects with the disease, we performed molecular analyses of the SRY gene in DNA from blood leukocytes and gonadal tissue in 12 true hermaphrodites with different karyotypes. Our results using PCR and FISH analyses reveal the presence of hidden mosaicism for SRY or other Y sequences in some patients with XX true hermaphroditism and confirms that mosaicism for SRY limited to the gonads is an alternative mechanism for testicular development in 46,XX true hermaphrodites.


Assuntos
Cromossomos Humanos Y/genética , Transtornos do Desenvolvimento Sexual/genética , Genes sry , Mosaicismo , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Reação em Cadeia da Polimerase , Diferenciação Sexual/genética
8.
Int J Infect Dis ; 6(1): 74-7, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12044307

RESUMO

OBJECTIVE: This study in a tertiary care teaching center with 361 beds was conducted to assess use, misuse, and abuse of antibiotics. MATERIALS AND METHODS: Every day of the study, a computer program was used to compile a list of patients' bedside records. On a specific day, the bedside charts of selected patients were reviewed to determine whether: (1) a justification for antibiotic prescription was recorded; (2) duration of antibiotic therapy had been defined; (3) suitable cultures had been obtained; and (4) treatment was appropriate for the infection to be treated. For 6 months, charts were evaluated 3 days per week. RESULTS: Of 750 bedside charts 500 (67%) were selected for review. Of the 500 patients, 175 (35%) did not receive antibiotics. The abuses or misuses of antibiotics most frequently observed among the 325 treated patients were no record of justification for the antibiotic prescribed (130/325, 40%); no appropriate blood or fluid samples obtained for culture (45/325, 14%); no subsequent control cultures or cultures obtained before modifying therapy (80/175, 46%); no indication of a planned duration of therapy (180/325, 55%); and improper dosage prescribed in relation to weight (25/325, 8%). Abuse or misuse of antibiotics was more frequently observed among surgical patients than among nonsurgical patients (P<0.05). CONCLUSION: Rational use of antibiotics should be emphasized in every training program as a main strategy to control the increase in drug resistance and to prolong the usefulness of antibiotics.


Assuntos
Antibacterianos/uso terapêutico , Revisão de Uso de Medicamentos , Hospitais Pediátricos , Hospitais de Ensino , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Infecções/tratamento farmacológico , Infecções/epidemiologia , Estudos Prospectivos , Inquéritos e Questionários
9.
Acta pediátr. costarric ; 16(2): 48-60, 2002. ilus
Artigo em Espanhol | LILACS | ID: lil-403848

RESUMO

Objetivo: Analizar y dar seguimiento en forma prospectiva hasta los 6 meses de edad a todos los niños que continuaban con oxígeno a los 15 días de edad, identificando la casuística, factores de riesgo, manejo y evolución. Materiales y métodos: del 1 de enero de 1997 al 30 de junio de 1998, se incluyeron todos los pacientes internados que requirieron oxígeno por más de 14 días continuos a quienes se les dio seguimiento hasta suspender el oxígeno o egresar, continuándose en la Clínica de oxígenodependencia el seguimieto hasta los 6 meses de edad, cerrándose el estudio el 30 de junio de 1997. Sitio: Servicio de Neonatología del Hospital Nacional de Niños "Dr. Carlos Saénz Herrera", San José Costa Rica, de Enero a Diciembre de 1997. Resultados: Se incluyeron 749 recién nacidos. De ellos, 526 (71 por ciento) ameritaron ventilación mécanica. 88 pacientes (12 por ciento) requierieron oxígeno suplementario por más de 14 días. El promedio de edad en que se suspende el oxígeno fue de 95.7 días (rango 16 y 395 días). De los niños que ameritaron O2 por más de 27 días, resolvieron su dependencia antes de los 6 meses el 77 por ciento (57/74), del resto solo 1 continuo con O2 al año de edad. La patología de ingreso más frecuente fue el S.I.R.I. (Síndrome de Insuficiencia Respiratoria por Inmadurez) o Membrana Hialina en el 66 por ciento. El 100 por ciento de los pacientes con peso menor de 1000 g vivos a los 28 días, eran oxígenodependientes. La ventilación mecánica fue necesaria en 86 (97.7 por ciento) pacientes, la duranción media fue de 16.4 días (1-82 días). Ameritaron oxígeno a los 28 días, 48 de 58 niños que se complicaron con septicemia, 37/43 con bronconeumonía, 23/29 con PCA, 13/15 con neumotorax y un paciente que hizo enfisema. Conclusión: Con los resultados de las nuevas técnicas ventilatorias que han demostrado disminución en la incidencia de DBP, como la ventilación de alta frecuencia y el uso de nuevas drogas que estan en investigación para utilizar en forma temprana y reducir el proceso inflamatorio que desencadena el desarrollo de esta enfermedad, se espera mejorar la evolución y prónostico de estos niños.


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Oxigênio/administração & dosagem , Consumo de Oxigênio , Respiração Artificial , Costa Rica
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