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1.
Environ Microbiol ; 15(8): 2228-37, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23425574

RESUMO

Río Tinto (Huelva, southwestern Spain) is an extreme environment with a remarkably constant acidic pH and a high concentration of heavy metals, conditions generated by the metabolic activity of chemolithotrophic microorganisms thriving in the rich complex sulfides of the Iberian Pyrite Belt (IPB). Fungal strains isolated from the Tinto basin were characterized morphologically and phylogenetically. The strain identified as Purpureocillium lilacinum specifically induced the formation of a yellow-ocher precipitate, identified as hydronium-jarosite, an iron sulfate mineral which appears in abundance on the banks of Río Tinto. The biomineral was characterized by X-ray diffraction (XRD) and its formation was observed with high-resolution transmission electron microscopy (TEM) and scanning electron microscopy (SEM) coupled to energy-dispersive X-ray spectroscopy (EDX) microanalysis. Jarosite began to nucleate on the fungal cell wall, associated to the EPS, due to a local increase in the Fe(3+) /Fe(2+) ratio which generated supersaturation. Its formation has been also observed in non-viable cells, although with much less efficiency. The occurrence of P. lilacinum in an ecosystem with high concentrations of ferric iron and sulfates such as Río Tinto suggests that it could participate in the process of jarosite precipitation, helping to shape and control the geochemical properties of this environment.


Assuntos
Compostos Férricos/metabolismo , Hypocreales/metabolismo , Sulfatos/metabolismo , Microbiologia da Água , Ecossistema , Compostos Férricos/química , Concentração de Íons de Hidrogênio , Hypocreales/isolamento & purificação , Hypocreales/ultraestrutura , Ferro/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Espanha , Sulfatos/química , Sulfetos/química
2.
Bol. pediatr ; 48(204): 124-127, 2008. ilus, tab
Artigo em Es | IBECS | ID: ibc-65180

RESUMO

La metahemoglobinemia es una causa de cianosis poco frecuente en la edad pediátrica, debida a la exposición a agentes oxidantes de la hemoglobina, como los nitratos, presentes en el agua o verduras (espinacas, acelgas, zanahorias, calabacín y judías verdes).La metahemoglobinemia asociada a alimentos infantiles ricos en nitratos ha sido descrita frecuentemente. El consumo de puré de verduras conservado deficientemente es una causa potencial de metahemoglobinemia infantil adquirida. Los lactantes de menos de 6 meses de edad son particularmente susceptibles a padecer esta entidad. Presentamos el caso de un lactante de 9 meses, traído al Servicio de Urgencias con cianosis central tras la ingesta de un puré de verduras preparado de forma casera y conservado en nevera durante más de 48 horas. El porcentaje de metahemoglobina determinado por cooximetría fue del12,1%. El cuadro se resolvió completamente en 6 horas sin precisar tratamiento con azul de metileno (AU)


Methemoglobinemia is a rare cause of cyanosis in paediatricage due to the exposure to haemoglobin-oxidizingagents such as nitrates present in well water or vegetables(spinach, beets, carrots, courgette and green beans).Methemoglobinemia associated with high-nitrate infant food has been reported frequently. Consumption of vegetable puree with an incorrect storage is a potential cause of acquired infantile methemoglobinemia. Infants younger than 6 months old are particularly susceptible to this condition. We report a case of a 9-month-old male infant who was brought to the paediatric emergency department with central cyanosis after eating a homemade mixed vegetable puree prepared in advance and stored in the refrigerator longer than 48 hours. His methemoglobin level determined by cooximetry was12.1%. After 6 hours, the syndrome was completely resolved without needing methylene blue treatment (AU)


Assuntos
Humanos , Masculino , Lactente , Cianose/diagnóstico , Metemoglobinemia/complicações , Cianose/etiologia , Alimentos Infantis/efeitos adversos , Diagnóstico Diferencial
6.
An Esp Pediatr ; 56(4): 337-41, 2002 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-11927078

RESUMO

Methylmalonic aciduria and homocystinuria is a very rare inborn error of cellular cobalamin (Cbl) metabolism. We describe the biochemical evolution and clinical course of a boy with neonatal onset CblC mutant defect.Born after a normal pregnancy, the patient developed general hypotonia and severe feeding difficulties at 5 days of life. Diagnosis of methylmalonic aciduria and homocystinuria was established by amino-acid and organic acid analysis and was confirmed by enzyme and genetic studies. The patient was initially treated with parenteral hydroxocobalamin (1 mg/day), oral carnitine (100 mg/kg/day) and a restricted protein diet. This treatment returned methylmalonic acid levels to normal. Despite the parenteral hydroxocobalamin therapy, the patient showed no improvement in neurological dysfunction, hypotonia or developmental delay. Oral betaine supplementation (3 g/day) from months 3-15 reduced plasma total homocysteine and homocystinuria. The patient showed clinical improvement in neurological and growth development. We conclude that early betaine therapy was safe and effective in our patient with neonatal onset methylmalonic aciduria and homocystinuria type CblC.


Assuntos
Betaína/uso terapêutico , Fármacos Gastrointestinais/uso terapêutico , Homocistinúria/tratamento farmacológico , Ácido Metilmalônico/urina , Administração Oral , Fatores Etários , Betaína/administração & dosagem , Fármacos Gastrointestinais/administração & dosagem , Homocistinúria/diagnóstico , Homocistinúria/genética , Humanos , Lactente , Recém-Nascido , Masculino , Fatores de Tempo
7.
An. esp. pediatr. (Ed. impr) ; 56(4): 337-341, abr. 2002.
Artigo em Es | IBECS | ID: ibc-6706

RESUMO

La aciduria metilmalónica con homocistinuria es un infrecuente error del metabolismo celular de la cobalamina (cbl). Se describe la evolución bioquímica y el curso clínico de un paciente con la mutación cblC de comienzo neonatal. Nacido tras una gestación normal, desarrolló una hipotonía general y graves dificultades de alimentación a los 5 días. El diagnóstico de aciduria metilmalónica con homocistinuria fue establecido basándose en los análisis de los aminoácidos y de los ácidos orgánicos, y confirmado mediante estudios enzimáticos y genéticos. El paciente fue tratado inicialmente con hidroxicobalamina parenteral (1 mg diario), carnitina oral (100 mg/kg/ día) y dieta hipoproteica. Este tratamiento normalizó los niveles de ácido metilmalónico. A pesar del tratamiento con hidroxicobalamina parenteral, la disfunción neurológica, la hipotonía y el retraso del desarrollo no experimentaron ninguna mejoría. La suplementación con betaína oral (3 g diarios) desde el 3.º al 15.º mes produjo una disminución de la homocisteína total y de la homocistinuria. El paciente presentó mejoría clínicamente de su desarrollo neurológico y somatométrico. Se concluye que el tratamiento precoz con betaína fue seguro y efectivo en nuestro paciente con aciduria metilmalónica con homocistinuria tipo cblC de inicio neonatal (AU)


Assuntos
Masculino , Recém-Nascido , Lactente , Humanos , Fatores de Tempo , Betaína , Administração Oral , Fatores Etários , Homocistinúria , Fármacos Gastrointestinais , Ácido Metilmalônico
9.
Appl Microbiol Biotechnol ; 49(4): 393-8, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9615480

RESUMO

A recombinant form of the sweet-tasting protein thaumatin has been produced in the filamentous fungus Aspergillus niger var. awamori. Expression cassettes containing a synthetic gene encoding thaumatin II were prepared and used to transform Aspergillus niger var. awamori strain NRRL312. Several fungal strains capable of synthesizing and secreting thaumatin into the culture medium were generated, and their production capabilities were determined, first in shake flasks and later in a laboratory fermentor. We report the expression and secretion of thaumatin in concentrations of 5-7 mg/l. This recombinant thaumatin is sweet.


Assuntos
Aspergillus niger/metabolismo , Proteínas de Plantas/metabolismo , Proteínas Recombinantes/metabolismo , Edulcorantes , Aspergillus niger/genética , Western Blotting , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Vetores Genéticos/genética , Proteínas de Plantas/genética , Reação em Cadeia da Polimerase , Proteínas Recombinantes/análise , Fatores de Tempo , Transformação Genética
10.
Biochem Biophys Res Commun ; 229(1): 121-7, 1996 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-8954093

RESUMO

A synthetic gene encoding the aminoacid sequence of the sweet-tasting protein thaumatin II has been assembled and expressed in Escherichia coli. Immunoblotting analysis shows that the expressed recombinant thaumatin has the same molecular weight as the protein from its natural source, the plant Thaumatoccocus daniellii Benth.


Assuntos
Genes Sintéticos , Proteínas de Plantas/biossíntese , Edulcorantes/metabolismo , Especificidade de Anticorpos , Clonagem Molecular , Escherichia coli/genética , Vetores Genéticos , Proteínas de Plantas/genética , Proteínas de Plantas/imunologia , Proteínas Recombinantes/biossíntese
12.
Curr Genet ; 29(2): 174-81, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8821665

RESUMO

The relatedness of nine isolates of Rhizoctonia solani, belonging to anastomosis group (AG) 4, and one isolate of AG1 was determined by comparative sequence analysis based on direct sequencing of PCR-amplified ribosomal DNA [the internal transcribed spacer (ITS) region and the 5.8 s ribosomal DNA]. The 5.8 s rDNA is completely conserved, but both ITS regions show variation among strains. AG1 was an outgroup based on anastomosis ability and RFLP analyses. Phylogenetic analyses based on the ITS sequences suggest that the analyzed AG4 strains can be divided into three groups that correlate with habitat and virulence.


Assuntos
DNA Ribossômico/química , Reação em Cadeia da Polimerase/métodos , Rhizoctonia/classificação , Rhizoctonia/fisiologia , Sequência de Bases , Bioensaio , Impressões Digitais de DNA/métodos , DNA Fúngico/química , Dados de Sequência Molecular , Filogenia , Rhizoctonia/patogenicidade , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie
13.
Appl Environ Microbiol ; 61(8): 2970-5, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16535098

RESUMO

Phototrophic growth of the moderate halotolerant Rhodobacter capsulatus strain E1F1 in media containing up to 0.3 M NaCl was dependent on the nitrogen source used. In these media, increased growth rates and growth levels were observed in the presence of reduced nitrogen sources such as ammonium and amino acids. When the medium contained an oxidized nitrogen source (dinitrogen or nitrate), increases in salinity severely inhibited phototrophic growth. However, the addition of glycine betaine promoted halotolerance and allowed the cells to grow in 0.2 M NaCl. Inhibition of diazotrophic growth by salinity was due to a decrease in nitrogenase activity which was no longer synthesized and reversibly inactivated, both effects being alleviated by the addition of glycine betaine. In R. capsulatus E1F1, inhibition of cell growth in nitrate by salt was due to a rapid inhibition of nitrate uptake, which led to a long-term decrease in nitrate reductase activity, probably caused by repression of the enzyme. Addition of glycine betaine immediately restored nitrate uptake, but the recovery of nitrate reductase activity required several hours. Neither ammonium uptake nor ammonium assimilation through the glutamine synthetase-glutamate synthase pathway was affected by NaCl.

15.
An Esp Pediatr ; 33(5): 435-41, 1990 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-2096757

RESUMO

The relapses and complications happened on the 17 cases of children with acute lymphoblastic leukemia in the Hospital General de Segovia have been reviewed from November 1974 to September 1989. Those which have a higher interest because of their relevance or infrequency have been under discussion. Among the relapses the pulmonary and the testicular are singled out. We differentiate between the complications produced during the treatment and the long-term ones, pointing up varicella as an infectious complication.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Varicela/etiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Fibrose Pulmonar/etiologia , Fibrose Pulmonar/patologia , Recidiva , Doenças Testiculares/etiologia , Doenças Testiculares/patologia
17.
An Esp Pediatr ; 26(4): 281-4, 1987 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-3605880

RESUMO

Authors report two cases of Crohn's disease in a brother and a sister. Female showed first manifestation at 8 years of age. Male started at 12 years. Onset was acute in the girl with ileo-cecal and colonic involvement and extraintestinal manifestations. The boy had an insidious onset with ileal involvement and striking rectal and perianal symptoms. In both cases, clinical course was chronic and relapsing. HLA A and B phenotypes were studied in both patients and their parents. Different factors concerning origin of disease, as well as relationship to other diseases among relatives are discussed.


Assuntos
Doença de Crohn/genética , Adolescente , Criança , Doença de Crohn/complicações , Feminino , Antígenos HLA , Humanos , Masculino , Linhagem , Fístula Retal/etiologia
18.
An Esp Pediatr ; 25(4): 251-6, 1986 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-3800171

RESUMO

Authors report case histories of four siblings with Munchausen syndrome by proxy. The diagnosis was made in the third daughter after six years. Two siblings had died as result of sudden unexplained death at two years old and twelve month old respectively. The mother had typical features outlined in some report. She denied the provocation of any episode and refused further psychiatric help but she accepted medical supervision. A review of the literature: warning signals, plan of action in order to assess the diagnosis and management of this problem are outlined, establishing a discussion about the repercussion of this syndrome.


Assuntos
Síndrome da Criança Espancada , Maus-Tratos Infantis , Síndrome de Munchausen/genética , Feminino , Hospitalização , Humanos , Lactente , Masculino , Síndrome de Munchausen/diagnóstico , Fatores de Tempo
19.
An Esp Pediatr ; 23(1): 26-30, 1985 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-4062071

RESUMO

To asses the value of preoperative tests in pediatric patients, a retrospective study of 722 surgical patients was undertaken. No unsuspected abnormalities or underlying diseases leading to the cancellation or postposition of surgery were found. Neither anaesthesia nor postoperatory complications were prevented by means of this procedure. We conclude that detailed anamnesis and physical examination are the most effective screening procedures and that radiologic and laboratory tests should be restricted to help in diagnosis and evaluation of the patient in emergency surgery and when the anamnesis, physical examination or a specific kind of surgery recommend it.


Assuntos
Pediatria , Cuidados Pré-Operatórios , Criança , Pré-Escolar , Estudos de Avaliação como Assunto , Humanos , Lactente , Recém-Nascido , Complicações Pós-Operatórias , Estudos Retrospectivos , Procedimentos Cirúrgicos Operatórios
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