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1.
An Acad Bras Cienc ; 94(3): e20211032, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36228304

RESUMEN

Tuberculosis remains a major health problem worldwide. Drug-resistant and hypervirulent Mycobacterium tuberculosis (Mtb) strains can lead to a hyperinflammatory response and necrotic pathology in hyper-reactive individuals that require adjunctive treatment. Plant-derived substances have been investigated for TB treatment, among which flavonoids stand out. We evaluate the anti-Mtb, anti-inflammatory and cytotoxicity activities of fractions and substances 1, 2 and 3 isolated from Erythrina verna through a bioassay guided fractionation. Seven fractions (1, 3-5 and 7-9) obtained from dichloromethane E. verna extract inhibited NO production (IC50 ≤ 15 µg/mL) with none or poor cytotoxic effect, while the fractions 4 and 5 notably reduced TNF-a production. Fractions 4, 6 and 9 suppressed Mycobacterium growth with MIC50 ≤ 20 µg/mL. Fraction 4 was the most potent due to dual biological activities. Erythratidinone and alpinumisoflavone inhibited the growth of Mtb H37Rv and hypervirulent strain in bacterial cultures (MIC50 ≤ 20 µg/mL), with erythratidinone standing out in reducing intracellular growth of Mtb H37Rv (5.8 ± 1.1 µg/mL). Alpinumisoflavone and erythratidinone were capable of inhibiting NO and TNF-α production besides showing significant inhibitory effects against Mycobacterium tuberculosis strains with low toxicity in macrophages. Both substances are promising for further studies focusing on an anti-TB dual treatment approach.


Asunto(s)
Erythrina , Mycobacterium tuberculosis , Antiinflamatorios/farmacología , Antituberculosos/farmacología , Flavonoides/farmacología , Humanos , Cloruro de Metileno , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/farmacología , Factor de Necrosis Tumoral alfa
2.
Br J Dermatol ; 180(3): 484-495, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-29897631

RESUMEN

These guidelines for the management of congenital ichthyoses have been developed by a multidisciplinary group of European experts following a systematic review of the current literature, an expert conference held in Toulouse in 2016, and a consensus on the discussions. These guidelines summarize evidence and expert-based recommendations and intend to help clinicians with the management of these rare and often complex diseases. These guidelines comprise two sections. This is part two, covering the management of complications and the particularities of some forms of congenital ichthyosis.


Asunto(s)
Consenso , Dermatología/normas , Eritrodermia Ictiosiforme Congénita/terapia , Ictiosis/terapia , Enfermedades del Prematuro/terapia , Dermatología/métodos , Europa (Continente) , Humanos , Eritrodermia Ictiosiforme Congénita/complicaciones , Ictiosis/complicaciones
3.
Br J Dermatol ; 180(2): 272-281, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30216406

RESUMEN

These guidelines for the management of congenital ichthyoses have been developed by a multidisciplinary group of European experts following a systematic review of the current literature, an expert conference held in Toulouse in 2016 and a consensus on the discussions. They summarize evidence and expert-based recommendations and are intended to help clinicians with the management of these rare and often complex diseases. These guidelines comprise two sections. This is part one, covering topical therapies, systemic therapies, psychosocial management, communicating the diagnosis and genetic counselling.


Asunto(s)
Terapia Conductista/normas , Consenso , Fármacos Dermatológicos/uso terapéutico , Dermatología/normas , Eritrodermia Ictiosiforme Congénita/terapia , Administración Oral , Administración Tópica , Terapia Conductista/métodos , Dermatología/métodos , Europa (Continente) , Asesoramiento Genético/normas , Humanos , Eritrodermia Ictiosiforme Congénita/diagnóstico , Eritrodermia Ictiosiforme Congénita/psicología , Calidad de Vida , Apoyo Social , Revisiones Sistemáticas como Asunto
4.
Eur Ann Allergy Clin Immunol ; 48(1): 22-6, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26808448

RESUMEN

Acute Hemorrhagic Edema of Infancy is a small vessel leucocytoclastic vasculitis affecting young infants. It is characterized by large, target-like, macular to purpuric plaques predominantly affecting the face, ear lobes and extremities. Non-pitting edema of the distal extremities and low-grade fever may also be present. Extra-cutaneous involvement is very rare. Although the lesions have a dramatic onset in a twenty-four to forty-eight hour period, usually the child has a non-toxic appearance. In most cases there are no changes in laboratory parameters. The cutaneous biopsy reveals an inflammatory perivascular infiltrate. It is a benign and auto-limited disease, with complete resolution within two to three weeks leaving no sequelae in the majority of cases. No recurrences are described. We report a case of a 42-day old girl admitted at our hospital with Acute Hemorrhagic Edema of Infancy.


Asunto(s)
Edema/complicaciones , Edema/diagnóstico , Vasculitis Leucocitoclástica Cutánea/complicaciones , Vasculitis Leucocitoclástica Cutánea/diagnóstico , Enfermedad Aguda , Diagnóstico Diferencial , Edema/inmunología , Femenino , Humanos , Lactante , Vasculitis Leucocitoclástica Cutánea/inmunología
5.
Fish Shellfish Immunol ; 35(4): 1216-23, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23911651

RESUMEN

The eel (Anguilla anguilla) has been identified as a vulnerable species with stocks dramatically declining over the past decade. In an effort to support the species from overfishing of wild stocks increased interest in eel aquaculture has been notable. In order to expand the scarce knowledge concerning the biology of this species significant research efforts are required in several fields of biology. The development of cell culture systems to study the immune response is a key step towards an increased understanding of the immune response and to develop resources to support further study in this threatened species. Macrophages are one of the most important effector cells of the innate immune system. The capacity to engulf pathogens and orchestrate the immune response relies on the existence of different surface receptors, such as scavenger receptors and toll-like receptors. We have developed and described an eel macrophage-like in vitro model and studied its functional and transcriptomic responses. Macrophage-like cells from both head kidney and purified peripheral blood leukocytes were obtained and phagocytic activity measured for different whole bacteria and yeast. Moreover, based on PAMP-PRR association the innate immune response of both head kidney and PBL derived macrophage-like cells was evaluated against different pathogen-associated molecular patterns (PAMPs). Results highlight that peptidoglycan stimulation strongly induces inflammatory mRNA expression reflected in the up-regulation of pro-inflammatory genes IL1ß and IL18 in PBL derived cells whereas IL8 is upregulated in head kidney derived cells. Furthermore TLR2 mRNA abundance is regulated by all stimuli supporting a multifunctional role for this pathogen recognition receptor (PRR) in eel macrophage-like cells.


Asunto(s)
Anguilla/genética , Anguilla/inmunología , Proteínas de Peces/genética , Regulación de la Expresión Génica , Inmunidad Innata , Macrófagos/metabolismo , Secuencia de Aminoácidos , Anguilla/metabolismo , Animales , Secuencia de Bases , Células Cultivadas , Clonación Molecular , ADN Complementario/genética , ADN Complementario/metabolismo , Escherichia coli/fisiología , Proteínas de Peces/química , Proteínas de Peces/metabolismo , Lipopolisacáridos/farmacología , Macrófagos/citología , Datos de Secuencia Molecular , Peptidoglicano/farmacología , Filogenia , Reacción en Cadena de la Polimerasa/veterinaria , ARN Mensajero/genética , ARN Mensajero/metabolismo , Saccharomyces cerevisiae/fisiología , Alineación de Secuencia/veterinaria , Staphylococcus aureus/fisiología , Zimosan/farmacología
6.
Water Sci Technol ; 66(4): 704-11, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22766856

RESUMEN

One of the most important causes for poor water quality in urban rivers in Brazil is the low collection efficiency of the sewer system due to unforeseen interconnections with the stormwater drainage system. Since the beginning of the 20th century, Brazilian cities have adopted separate systems for sanitary sewers and stormwater runoff. Gradually these two systems became interconnected. A major challenge faced today by water managers in Brazil is to find efficient and low cost solutions to deal with this mixed system. The current situation poses an important threat to the improvement of the water quality in urban rivers and lakes. This article presents an evaluation of the water quality parameters and the diffuse pollution loads during rain events in the Pinheiros River, a tributary of the Tietê River in São Paulo. It also presents different types of integrated solutions for reducing the pollution impact of combined systems, based on the European experience in urban water management. An evaluation of their performance and a comparison with the separate system used in most Brazilian cities is also presented. The study is based on an extensive water quality monitoring program that was developed for a special investigation in the Pinheiros River and lasted 2.5 years. Samples were collected on a daily basis and water quality variables were analyzed on a daily, weekly or monthly basis. Two hundred water quality variables were monitored at 53 sampling points. During rain events, additional monitoring was carried out using an automated sampler. Pinheiros River is one of the most important rivers in the São Paulo Metropolitan Region and it is also a heavily polluted one.


Asunto(s)
Ríos/química , Contaminantes del Agua/análisis , Contaminación del Agua/prevención & control , Amoníaco/análisis , Análisis de la Demanda Biológica de Oxígeno , Brasil , Ciudades , Drenaje de Agua , Monitoreo del Ambiente , Escherichia coli/aislamiento & purificación , Nitratos/análisis , Nitritos/análisis , Fósforo/análisis , Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Movimientos del Agua
7.
J Dermatolog Treat ; 33(5): 2554-2559, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35083945

RESUMEN

INTRODUCTION: Atopic dermatitis (AD) is a difficult-to-treat inflammatory skin disease with a high impact on patients' quality of life. Dupilumab, an IL-4 and IL-13 inhibitor, was the first monoclonal antibody approved for the treatment of moderate-to-severe AD and is currently approved in patients aged 6 or older. METHODS: This is a nationwide, multicenter, retrospective, 48-week study designed by the Portuguese Group of AD to assess real-world efficacy and safety of dupilumab for the treatment of AD. RESULTS: A total of 169 patients were enrolled, with a mean disease duration of 22.75 (±11.98) years. The percentage of patients achieving an improvement of at least 75% in Eczema Area and Severity Index (EASI) compared to baseline (EASI75 response) at weeks 12 and 48 was 67.6% and 74.1%, respectively. In the same timepoints, 25.0% and 44.1% achieved an EASI90 response. Patient-reported outcome measures also improved throughout the study period. Regarding safety, 32.0% of the patients developed adverse events, with conjunctivitis (26.6%), persistent facial erythema (4.7%), and arthritis/arthralgia (3.6%) as the more frequently reported. CONCLUSION: Data from real-world populations are crucial to guide clinicians in their daily decisions. This study provides data demonstrating that dupilumab is an effective and safe therapeutic option for AD.


Asunto(s)
Dermatitis Atópica , Anticuerpos Monoclonales Humanizados , Dermatitis Atópica/tratamiento farmacológico , Humanos , Portugal , Calidad de Vida , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
8.
Epidemiol Infect ; 139(3): 472-81, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20492749

RESUMEN

In 1996 an outbreak of severe soft tissue infections caused by Vibrio vulnificus unexpectedly erupted in fish consumers in Israel with relatively little morbidity in fish farmers. To test the hypothesis that recurrent exposure of fishermen to the virulent strain may have provided protection against severe or symptomatic disease, we investigated the association between the immune response to V. vulnificus biotype 3 lipopolysaccharide (BT3 LPS) and disease susceptibility in fish farmers and fish consumers. Serum samples were tested for IgA and IgG of anti-BT3 LPS in fishermen and fish consumers who suffered from V. vulnificus BT3 infections and their matched controls. Pre-existing levels of IgG (IgG0) of anti-BT3 LPS were significantly lower in diseased fishermen who developed disease associated with the homologous biotype, compared to controls. In multivariate analysis, levels of IgG0 anti-BT3 LPS remained the only variable significantly associated with disease occurrence in fishermen. Higher levels of pre-existing IgG anti-BT 3 LPS antibodies may be associated with protection against severe or symptomatic disease with the homologous biotype in fishermen but not in subjects from the general public.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Susceptibilidad a Enfermedades , Lipopolisacáridos/inmunología , Vibriosis/inmunología , Vibrio vulnificus/inmunología , Estudios de Casos y Controles , Femenino , Humanos , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Israel , Masculino , Persona de Mediana Edad , Suero/inmunología , Vibriosis/prevención & control
9.
J Eur Acad Dermatol Venereol ; 24(7): 844-6, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19929939

RESUMEN

BACKGROUND: Trichoepitheliomas are benign neoplasms with follicular differentiation. They may present as a solitary lesion or as multiple lesions. Multiple trichoepitheliomas are inherited in an autosomal dominant pattern within families, with both variable penetrance and expressivity. Recent investigations support that mutations in CYLD, the gene affected in familial cylindromatosis as well as in Brooke-Spiegler syndrome, are also responsible for multiple trichoepitheliomas. OBJECTIVE: The authors report the case of a 9-year-old African girl with multiple facial trichoepitheliomas in whom a mutation in the CYLD gene was hypothesised. MATERIALS AND METHODS: After genomic DNA extraction from the peripheral blood, a molecular analysis of the CYLD gene was performed by PCR, DHPLC and automated sequencing. RESULTS: A novel heterozygous mutation in exon 18 of the CYLD gene (c.2449delT) was identified, with a deletion of one nucleotide resulting in a premature translational termination codon at amino acid position 831 on the affected allele (p.Cys817Valfs X15). CONCLUSIONS: The predominating tumours define the classification of these three entities. Nevertheless, studies suggest that they can simply represent phenotypic variations of the same disease spectrum, sharing common genetic mutations.


Asunto(s)
Mutación , Neoplasias Cutáneas/genética , Proteínas Supresoras de Tumor/genética , Secuencia de Aminoácidos , Secuencia de Bases , Niño , Cromatografía Líquida de Alta Presión , ADN , Enzima Desubiquitinante CYLD , Femenino , Humanos , Reacción en Cadena de la Polimerasa
10.
J Fish Dis ; 33(5): 383-90, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20158583

RESUMEN

Vibrio vulnificus biotype 2 is subdivided into two main serovars, serovar E, able to infect fish and humans, and serovar A, only virulent for fish. Serovar E emerged in 1976 as the causative agent of a haemorrhagic septicaemia (warm-water vibriosis) affecting eels cultured in brackish water. Serovar A emerged in 2000 in freshwater-cultured eels vaccinated against serovar E, causing warm-water vibriosis with fish showing a haemorrhagic intestine as the main differential sign. The aim of the present work was to compare the disease caused by both serovars in terms of transmission routes, portals of entry and host range. Results of bath, patch-contact and oral-anal challenges demonstrated that both serovars spread through water and infect healthy eels, serovar A entering mainly by the anus and serovar E by the gills. The course of the disease under laboratory conditions was similar for both serovars in terms of transmission and dependence of degree of virulence on water parameters (temperature and salinity). However, the decrease in degree of virulence in fresh water was significantly greater in serovar E than in serovar A. Finally, both serovars proved pathogenic for tilapia, sea bass and rainbow trout, but not for sea bream, with significant differences in degree of virulence only in rainbow trout. In conclusion, serovar A seems to represent a new antigenic form of V. vulnificus biotype 2 with an unusual portal of entry and is better adapted to fresh water than serovar E.


Asunto(s)
Enfermedades de los Peces/microbiología , Vibriosis/veterinaria , Vibrio vulnificus/patogenicidad , Animales , Enfermedades de los Peces/epidemiología , Enfermedades de los Peces/mortalidad , Enfermedades de los Peces/transmisión , Peces , Interacciones Huésped-Patógeno , Dosificación Letal Mediana , Salinidad , Serotipificación , Temperatura , Vibriosis/epidemiología , Vibriosis/microbiología , Vibriosis/mortalidad , Vibriosis/transmisión
12.
Curr Oncol ; 27(Suppl 3): S173-S180, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33343211

RESUMEN

Hepatocellular carcinoma (hcc) is one of the most common cancers in the world. It has a high mortality rate, especially when localized treatments fail. For about a decade, the only systemic treatment shown to improve survival was sorafenib. Recently, lenvatinib was found to be noninferior to sorafenib for overall survival, and combination atezolizumab-bevacizumab improved survival compared with sorafenib. Similarly, in the post-sorafenib setting, a number of recent positive clinical trials have been reported, and they indicate that regorafenib, cabozantinib, and ramucirumab are effective and safe in the second-line setting. With so many new options available, including immunotherapy, it is challenging to define the best sequence of systemic treatment for patients with hcc. In the present review, we introduce the current data for second-line systemic treatment and beyond in hcc. A treatment algorithm is also suggested, based on the best available evidence and expert opinion.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/tratamiento farmacológico , Humanos , Inmunoterapia , Neoplasias Hepáticas/tratamiento farmacológico , Inhibidores de Proteínas Quinasas , Sorafenib
13.
Appl Environ Microbiol ; 75(8): 2577-80, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19218407

RESUMEN

This work demonstrates that Vibrio vulnificus biotype 2, serovar E, an eel pathogen able to infect humans, can become resistant to quinolone by specific mutations in gyrA (substitution of isoleucine for serine at position 83) and to some fluoroquinolones by additional mutations in parC (substitution of lysine for serine at position 85). Thus, to avoid the selection of resistant strains that are potentially pathogenic for humans, antibiotics other than quinolones must be used to treat vibriosis on farms.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Quinolonas/farmacología , Vibrio vulnificus/efectos de los fármacos , Animales , Proteínas Bacterianas/genética , Girasa de ADN/genética , Topoisomerasa de ADN IV/genética , ADN Bacteriano/química , ADN Bacteriano/genética , Anguilas/microbiología , Datos de Secuencia Molecular , Mutación Missense , Análisis de Secuencia de ADN , Vibrio vulnificus/aislamiento & purificación
14.
Virulence ; 9(1): 981-993, 2018 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-29697309

RESUMEN

Vibrio vulnificus can be a highly invasive pathogen capable of spreading from an infection site to the bloodstream, causing sepsis and death. To survive and proliferate in blood, the pathogen requires mechanisms to overcome the innate immune defenses and metabolic limitations of this host niche. We created a high-density transposon mutant library in YJ016, a strain representative of the most virulent V. vulnificus lineage (or phylogroup) and used transposon insertion sequencing (TIS) screens to identify loci that enable the pathogen to survive and proliferate in human serum. Initially, genes underrepresented for insertions were used to estimate the V. vulnificus essential gene set; comparisons of these genes with similar TIS-based classification of underrepresented genes in other vibrios enabled the compilation of a common Vibrio essential gene set. Analysis of the relative abundance of insertion mutants in the library after exposure to serum suggested that genes involved in capsule biogenesis are critical for YJ016 complement resistance. Notably, homologues of two genes required for YJ016 serum-resistance and capsule biogenesis were not previously linked to capsule biogenesis and are largely absent from other V. vulnificus strains. The relative abundance of mutants after exposure to heat inactivated serum was compared with the findings from the serum screen. These comparisons suggest that in both conditions the pathogen relies on its Na+ transporting NADH-ubiquinone reductase (NQR) complex and type II secretion system to survive/proliferate within the metabolic constraints of serum. Collectively, our findings reveal the potency of comparative TIS screens to provide knowledge of how a pathogen overcomes the diverse limitations to growth imposed by serum.


Asunto(s)
Proteínas Bacterianas/genética , Sangre/microbiología , Vibriosis/microbiología , Vibrio vulnificus/crecimiento & desarrollo , Vibrio vulnificus/genética , Animales , Proteínas Bacterianas/metabolismo , Elementos Transponibles de ADN , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Vibriosis/sangre , Vibrio vulnificus/metabolismo , Vibrio vulnificus/patogenicidad , Virulencia
15.
J Laryngol Otol ; 129(2): 183-6, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25619547

RESUMEN

BACKGROUND: Lyme disease is an uncommon tick-borne multisystemic infection caused by Borrelia burgdorferi. The most common clinical manifestation is erythema migrans. In this report, a very unusual presentation of this condition is described, in which sudden onset sensorineural hearing loss was the sole presenting symptom. METHODS: Case report and review of English-language literature. RESULTS: A patient presented with sensorineural hearing loss, with no other symptoms or signs. Acute Lyme infection was detected by laboratory tests. Magnetic resonance imaging showed signs of labyrinthitis of the same inner ear. After hyperbaric oxygen and systemic antibiotic treatment, the patient showed total hearing recovery, and magnetic resonance imaging showed complete resolution of the labyrinthitis. CONCLUSION: To our knowledge, this is the first reported case of Lyme disease presenting only with sensorineural hearing loss. Borreliosis should be considered as an aetiological factor in sensorineural hearing loss. Adequate treatment may provide total recovery and prevent more severe forms of Lyme disease.


Asunto(s)
Pérdida Auditiva Súbita/microbiología , Enfermedad de Lyme/diagnóstico , Corticoesteroides/administración & dosificación , Adulto , Borrelia burgdorferi/aislamiento & purificación , Femenino , Pérdida Auditiva Súbita/sangre , Humanos , Oxigenoterapia Hiperbárica , Laberintitis/microbiología , Laberintitis/patología , Laberintitis/terapia , Enfermedad de Lyme/sangre , Enfermedad de Lyme/fisiopatología , Imagen por Resonancia Magnética/métodos , Acúfeno/microbiología , Acúfeno/patología , Vértigo/microbiología , Vértigo/patología
17.
FEMS Microbiol Lett ; 117(1): 85-90, 1994 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-7514147

RESUMEN

The relationship between virulence, O-serogroup, and some cell-surface features (self-pelleting [SP] and precipitation after boiling [PAB], profile of lipopolysaccharides [LPSs] and outer membrane proteins [OMPs]) was investigated in strains of the pathogenic species Aeromonas hydrophila and A. jandaei isolated from eels. Virulent strains of A. hydrophila reacted mostly with O:19 antiserum, and those of A. jandaei reacted with O:4, O:11, O:15 and O:29 antisera (Guinée and Jansen system). Regarding the PAB and LPS profiles two groups could be distinguished; (i) five PAB+ strains of serotype O:19 that possessed a homogeneous O polysaccharide side chain and (ii) thirteen PAB- strains antigenically diverse that either exhibited a heterogeneous side chain or were side chain deficient. A major 50 kDa protein was only found in the PAB+ strains, whereas major OMPs detected in PAB- strains ranged from 33 to 45 kDa irrespective of the species. Epizootic eel isolates of A. hydrophila belong to serotype O:19 and share cell-surface features with the Aeromonas highly virulent for other hosts. In contrast, epizootic A. jandaei isolates were antigenically diverse. These findings reinforce the importance of an O-serotype as an epidemiological marker in motile Aeromonas strains pathogenic for eels.


Asunto(s)
Aeromonas hydrophila/clasificación , Aeromonas/clasificación , Anguilas/microbiología , Aeromonas/inmunología , Aeromonas/patogenicidad , Aeromonas hydrophila/inmunología , Aeromonas hydrophila/patogenicidad , Animales , Anticuerpos Antibacterianos , Proteínas de la Membrana Bacteriana Externa/química , Proteínas de la Membrana Bacteriana Externa/inmunología , Membrana Celular/inmunología , Lipopolisacáridos/química , Lipopolisacáridos/inmunología , Antígenos O , Fenotipo , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/inmunología , Serotipificación , Virulencia
18.
FEMS Microbiol Lett ; 107(2-3): 217-22, 1993 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-8472904

RESUMEN

The outer membrane proteins of 17 Vibrio vulnificus biotype 2 strains from Japanese and European eels, and 12 biotype 1 strains from clinical and environmental sources have been compared. The overall profile in both biotypes was similar, and a major protein band of molecular mass 36 kDa was detected in the majority of the strains. Differences in the minor bands allowed differentiation of strains from different origins, suggesting that outer membrane protein profiles could be useful as epidemiological markers in the species V. vulnificus. Immunoblotting with antisera to whole cells of selected strains of biotypes 1 and 2 showed a strong antigenic response to outer membrane proteins 66, 60, 48, 46 and 44 kDa; these were common to all strains examined, independent of their biotypes and origins. These results demonstrate the presence of antigenically related outer membrane proteins in both biotypes of V. vulnificus.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/química , Vibrio/química , Animales , Antígenos Bacterianos/química , Proteínas de la Membrana Bacteriana Externa/clasificación , Técnicas de Tipificación Bacteriana , Western Blotting , Anguilas/microbiología , Electroforesis en Gel de Poliacrilamida , Peso Molecular , Especificidad de la Especie , Vibrio/clasificación , Vibrio/inmunología
19.
FEMS Microbiol Lett ; 48(1): 7-12, 1989 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-2523837

RESUMEN

Iron uptake mechanisms were investigated in different species of Salmonella isolated from environmental waters. All strains examined were able to grow in the presence of high concentrations (10 mM) of the iron chelator EDDA. All strains excreted phenolate and hydroxamate siderophores, as assessed by bioassays and chemical tests. Bioassays with different indicator strains showed that all Salmonella strains can cross-feed other Enterobacteria, as well as mutants of Salmonella typhimurium deficient in the Enterobactin system, suggesting that this siderophore may be produced by the environmental Salmonella strains. The siderophore aerobactin may also be produced by one of the strains, according to the bioassays results. The same pattern of outer membrane proteins are synthesized under iron-limiting conditions in all species tested, which suggests a similarity of iron uptake systems in many species of Salmonella. This system could be also of great importance in the survival of these bacteria in natural waters, as well as in possible pathogenic mechanisms.


Asunto(s)
Quelantes del Hierro/metabolismo , Salmonella/metabolismo , Proteínas de la Membrana Bacteriana Externa/metabolismo , Ionóforos/metabolismo , Hierro/metabolismo , Sideróforos , Especificidad de la Especie
20.
FEMS Microbiol Lett ; 168(2): 181-6, 1998 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-9835027

RESUMEN

The survival of fish-virulent strains of Photobacterium damselae subsp. damselae in seawater microcosms, with and without sediment, was investigated. The strains survived as culturable bacteria at 14 and 22 degrees C for at least 1 year, and infectivity for fish was maintained. At 5 degrees C, cells lost culturability on solid media, but this was recovered when the temperature was increased to 22 degrees C. Finally, morphological changes in the bacterium (rod to coccus), and production of vesicles and extracellular material were observed during the time of starvation. The overall results suggest that seawater and sediment can act as reservoirs for these virulent strains.


Asunto(s)
Photobacterium/fisiología , Photobacterium/patogenicidad , Agua de Mar/microbiología , Animales , Frío , Recuento de Colonia Microbiana , Medios de Cultivo , Peces/microbiología , Sedimentos Geológicos , Ratones , Microscopía Electrónica de Rastreo , Photobacterium/aislamiento & purificación , Photobacterium/ultraestructura , Virulencia
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