Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Genes Immun ; 13(1): 21-8, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21716315

RESUMEN

Cytokine and cytokine receptor genes, including IL2RA, IL7R and IL12A, are known risk factors for multiple sclerosis (MS). Excitotoxic oligodendroglial death mediated by glutamate receptors contributes to demyelinating reactions. In the present study, we screened 368 single-nucleotide polymorphisms (SNPs) in 55 genes or gene clusters coding for cytokines, cytokine receptors, suppressors of cytokine signaling (SOCS), complement factors and glutamate receptors for association with MS in a Spanish-Basque resident population. Top-scoring SNPs were found within or nearby the genes coding for SOCS-1 (P=0.0005), interleukin-28 receptor, alpha chain (P=0.0008), oncostatin M receptor (P=0.002) and interleukin-22 receptor, alpha 2 (IL22RA2; P=0.003). The SOCS1 rs243324 variant was validated as risk factor for MS in a separate cohort of 3919 MS patients and 4003 controls (combined Cochran-Mantel-Haenszel P=0.00006; odds ratio (OR)=1.13; 95% confidence interval (CI)=1.07-1.20). In addition, the T allele of rs243324 was consistently increased in relapsing-remitting/secondary progressive versus primary-progressive MS patients, in each of the six data sets used in this study (P(CMH)=0.0096; OR=1.24; 95% CI 1.05-1.46). The association with SOCS1 appears independent from the chr16MS risk locus CLEC16A.


Asunto(s)
Predisposición Genética a la Enfermedad , Esclerosis Múltiple/genética , Proteínas Supresoras de la Señalización de Citocinas/genética , Adulto , Cromosomas Humanos Par 16 , Femenino , Frecuencia de los Genes , Haplotipos , Humanos , Lectinas Tipo C/genética , Masculino , Esclerosis Múltiple/inmunología , Polimorfismo de Nucleótido Simple , Reproducibilidad de los Resultados , Factores de Riesgo , Proteína 1 Supresora de la Señalización de Citocinas , Adulto Joven
2.
Stem Cell Res ; 49: 102082, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33221676

RESUMEN

APDS2 is caused by mutations in PIK3R1 gene resulting in constitutive PI3Kδ activation. PI3Kδ is predominantly expressed in leukocytes and plays critical roles in regulating immune responses. Here we first derived fibroblast primary cells from a skin biopsy of a patient carrying a heterozygous single T deletion in intron 11 of the PIK3R1 gene. We next present the derivation of an induced pluripotent stem cell (iPS) line using a non-integrative reprogramming technology. Pluripotent-related hallmarks are further shown, including: iPSCs self-renewal and expression of pluripotent and differentiation markers after in vitro differentiation towards embryonic germ layers, assessed by RT-PCR and immunofluorescence.


Asunto(s)
Línea Celular , Células Madre Pluripotentes Inducidas , Enfermedades de Inmunodeficiencia Primaria/genética , Diferenciación Celular , Fosfatidilinositol 3-Quinasa Clase I/genética , Fibroblastos , Humanos , Mutación
3.
Genes Immun ; 10(6): 596-600, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19458622

RESUMEN

The objective of this study was to identify additional diabetes susceptibility markers in the MHC that could be responsible for the differential diabetogenicity of different HLA-DR3 CEHs. High-resolution SNP genotyping of the MHC was carried out in 15 type 1 diabetes (T1D) patients and 39 non-diabetic controls, homozygous for DR3-DQ2 and with one copy of the A(*)30-B(*)18-MICA(*)4-F1C30-DRB1(*)0301-DQB1(*)0201-DPB1(*)0202 HLA haplotype. Significantly associated SNPs were replicated in an independent sample of 554 T1D patients and 841 controls without HLA matching. Electrophoretic mobility shift assay was used to show a functional effect of an associated SNP. Seven SNPs showed evidence of association in the initial discovery experiment. Upon replication, only rs419434 (upstream HLA-DOA gene) remained significant. A functional variant (rs432375) in complete LD with rs419434 was shown to affect USF-1 binding and could be responsible for the association signal in the region. We have identified a new susceptibility locus within the MHC with a modest contribution to T1D (OR=1.93; CI: 1.52-2.44; P=10(-8)) that is independent of HLA-DRB1 locus.


Asunto(s)
Diabetes Mellitus Tipo 1/genética , Antígenos HLA-B/genética , Antígenos HLA-D/genética , Antígeno HLA-DR3/genética , Haplotipos/genética , Polimorfismo de Nucleótido Simple/genética , Estudios de Casos y Controles , Diabetes Mellitus Tipo 1/epidemiología , Diabetes Mellitus Tipo 1/inmunología , Ensayo de Cambio de Movilidad Electroforética , Genotipo , Antígeno HLA-B18 , Humanos , Repeticiones de Microsatélite/genética , Pronóstico , España/epidemiología
4.
J Crohns Colitis ; 13(3): 351-361, 2019 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-30329026

RESUMEN

BACKGROUND AND AIMS: Steroid-refractoriness is a common and unpredictable phenomenon in ulcerative colitis [UC], but there are no conclusive studies on the molecular functions involved. We aimed to assess the mechanism of action related to steroid failure by integrating transcriptomic data from UC patients, and updated molecular data on UC and glucocorticoids. METHODS: MicroRNA [miRNA] and mRNA expression were evaluated by sequencing and microarrays, respectively, from rectal biopsies of patients with moderately-to-severe active UC, obtained before and on the third day of steroid treatment. The differential results were integrated into the mathematical models generated by a systems biology approach. RESULTS: This computational approach identified 18 proteins that stand out either by being associated with the mechanism of action or by providing a means to classify the patients according to steroid response. Their biological functions have been linked to inflammation, glucocorticoid-induced transcription and angiogenesis. All the selected proteins except ANP32E [a chaperone which has been linked to the exchange of H2A.z histone and promotes glucocorticoid receptor-induced transcription] had previously been related to UC and/or glucocorticoid-induced biological actions. Western blot and immunofluorescence assays confirmed the implication of this chaperone in steroid failure in patients with active UC. CONCLUSIONS: A systems biology approach allowed us to identify a comprehensive mechanism of action of steroid-refractoriness, highlighting the key role of steroid-induced transcription and the potential implication of ANP32E in this phenomenon.


Asunto(s)
Colitis Ulcerosa/tratamiento farmacológico , Resistencia a Medicamentos/genética , Glucocorticoides/farmacología , MicroARNs/análisis , Proteínas Nucleares/genética , Fosfoproteínas/genética , ARN Mensajero/análisis , Estudios de Casos y Controles , Expresión Génica/efectos de los fármacos , Perfilación de la Expresión Génica , Glucocorticoides/uso terapéutico , Humanos , Mucosa Intestinal/metabolismo , Chaperonas Moleculares , Proteínas Nucleares/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Fosfoproteínas/metabolismo , Biología de Sistemas , Transcripción Genética/efectos de los fármacos
5.
Cir Pediatr ; 21(4): 191-4, 2008 Oct.
Artículo en Español | MEDLINE | ID: mdl-18998366

RESUMEN

The investigation of a male with impalpable testes is one of the most frequent diagnostic indications of laparoscopy and it is accepted as a therapeutic tool for the treatment of the intra-abdominal testis. We have studied thirteen patients being surgically operated by a video-assisted orchidopexy without spermatic vessels section. The technique consists of wide mobilization of the spermatic vessels and the vas deferens from the posterior peritoneum, sectioning the gubernaculum and descending of the testis to the scrotum. In all the cases, the internal groin ring was later closed by means of a laparoscopy. There were no intraoperative complications. In 100% of the cases, the testis was descended to the scrotum. The surgical time oscillated between 40 and 80 minutes (60 minutes mean). At follow-up from 6 months to 4 years, the outcome was satisfactory in 11 patients, whereas in 2 cases the operated testis ascended.


Asunto(s)
Criptorquidismo/cirugía , Laparoscopía , Niño , Humanos , Masculino , Resultado del Tratamiento
6.
Artículo en Inglés, Español | MEDLINE | ID: mdl-30197166

RESUMEN

OBJECTIVE: The aim of this study is to determine the risk factors involved in the development of these fractures and analyze the treatments used as well as their influence on the clinical and functional prognosis of patients. MATERIALS AND METHODS: We made an observational, retrospective case-control study, with a sample of 38 patients (40 femoral bones) operated in our hospital, who had two femoral ipsilateral implants, proximal and distal. We found 10 cases of interimplant fracture and 28 patients who had not suffered a fracture (2 of them had bilateral implants). We analyzed the influence of different variables, such as age, gender, comorbidities, radiological variables, type of treatments employed, clinical evolution, etc. RESULTS: the female sex was predominant in both groups, 80.7 was the average age. Osteoporosis was statistically significant (P=.007) for the development of these fractures. We did not find statistical significance in the radiological variables. Surgical treatment was the most frequent, and the plate of osteosynthesis the most employed option. We found a death rate of 40% at 4 years. Although all fractures healed, the survivors' ambulation ability was reduced. CONCLUSIONS: interimplant fractures are predominant in elderly women. Osteoporosis is a statistically significant risk factor. Despite optimal treatment and fracture healing, functional outcomes were decreased. Specific classification systems and therapeutic algorithms are necessary to improve the management and prognosis of these patients.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Fracturas de Cadera , Traumatismos de la Rodilla , Fracturas Periprotésicas , Complicaciones Posoperatorias , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Fijación Interna de Fracturas/métodos , Fracturas de Cadera/diagnóstico , Fracturas de Cadera/etiología , Fracturas de Cadera/cirugía , Humanos , Traumatismos de la Rodilla/diagnóstico , Traumatismos de la Rodilla/etiología , Traumatismos de la Rodilla/cirugía , Masculino , Fracturas Periprotésicas/diagnóstico , Fracturas Periprotésicas/etiología , Fracturas Periprotésicas/cirugía , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
7.
Acta Trop ; 93(1): 75-83, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15589800

RESUMEN

Two PCR methods were compared for their sensitivity in detecting cultured Leishmania major, before being used to estimate infection rates in female sandflies (Phlebotomus papatasi) collected from peridomestic animal shelters and the nearby burrows of the gerbil reservoir hosts, Rhombomys opimus, in Isfahan province, central Iran. A semi-nested PCR was used to amplify a fragment of minicircle kinetoplast (k) DNA with a length and sequence diagnostic for L. major, and a nested PCR was developed to amplify a fragment containing the internal transcribed spacers of the ribosomal RNA genes (ITS-rDNA) with a sequence diagnostic for L. major. The semi-nested PCR was less sensitive than the nested PCR when using DNA extracted from cultured promastigotes of L. major, but it was more sensitive for detecting L. major in wild-caught sandflies. At the edges of two Isfahan villages, infection rates were significantly higher in P.papatasi collected outside gerbil burrows (14/28) compared with those from peridomestic animal shelters (2/21). This is the first record of L. major detected in P.papatasi from peridomestic sites in Isfahan province.


Asunto(s)
Leishmania major/genética , Leishmaniasis Cutánea/parasitología , Phlebotomus/parasitología , Reacción en Cadena de la Polimerasa/métodos , Animales , ADN de Cinetoplasto/química , ADN de Cinetoplasto/genética , ADN Protozoario/química , ADN Protozoario/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Femenino , Gerbillinae , Irán , Leishmania major/aislamiento & purificación , Población Rural , Sensibilidad y Especificidad , Análisis de Secuencia de ADN
8.
Cell Death Differ ; 22(1): 131-44, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25168244

RESUMEN

Tribbles pseudokinase-3 (TRIB3) has been proposed to act as an inhibitor of AKT although the precise molecular basis of this activity and whether the loss of TRIB3 contributes to cancer initiation and progression remain to be clarified. In this study, by using a wide array of in vitro and in vivo approaches, including a Trib3 knockout mouse, we demonstrate that TRIB3 has a tumor-suppressing role. We also find that the mechanism by which TRIB3 loss enhances tumorigenesis relies on the dysregulation of the phosphorylation of AKT by the mTORC2 complex, which leads to an enhanced phosphorylation of AKT on Ser473 and the subsequent hyperphosphorylation and inactivation of the transcription factor FOXO3. These observations support the notion that loss of TRIB3 is associated with a more aggressive phenotype in various types of tumors by enhancing the activity of the mTORC2/AKT/FOXO axis.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Factores de Transcripción Forkhead/metabolismo , Neoplasias/metabolismo , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Represoras/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Animales , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Proteína Forkhead Box O3 , Factores de Transcripción Forkhead/genética , Humanos , Diana Mecanicista del Complejo 2 de la Rapamicina , Ratones , Ratones Noqueados , Ratones Desnudos , Complejos Multiproteicos/genética , Complejos Multiproteicos/metabolismo , Neoplasias/genética , Neoplasias/patología , Fosforilación/genética , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Represoras/genética , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Proteínas Supresoras de Tumor/genética
9.
J Pediatr Surg ; 28(7): 948-9, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8229575

RESUMEN

Intraluminal masses within the upper urinary tracts are rare, are almost always benign, and most commonly take the form of fibroepithelial polyps within the ureters. Only exceptionally are these lesions found within the renal pelvis and for that reason may cause diagnostic difficulty. We present a new case of fibroepithelial polyp of the renal pelvis treated successfully in our hospital.


Asunto(s)
Neoplasias Renales/diagnóstico , Pelvis Renal , Pólipos/diagnóstico , Niño , Humanos , Neoplasias Renales/cirugía , Masculino , Pólipos/cirugía
10.
Cir Pediatr ; 2(2): 69-71, 1989 Apr.
Artículo en Español | MEDLINE | ID: mdl-2485672

RESUMEN

Distal hypospadias are the most frequent form of all. Many surgical procedures have been described. We present a series of 84 patients treated using a modification of the technique described in 1967 by Saint Aubert, known as preputioplasty. We described the technique employed. Our esthetics and functional results are excellent. There was a very low complication rate: 1.1 percent of fistulas and 2.3 percent of preputial dehiscence. In 4.7 percent of the patients there was a redundant prepuce. The final result is a non-circumcised appearance which is quite important in our sociocultural ambience.


Asunto(s)
Hipospadias/cirugía , Pene/cirugía , Niño , Preescolar , Estudios de Evaluación como Asunto , Humanos , Masculino , Métodos
11.
Genome Announc ; 2(6)2014 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-25395646

RESUMEN

We report the complete genome sequence of Acinetobacter baumannii strain AbH12O-A2, isolated during a large outbreak in Spain. The genome has 3,875,775 bp and 3,526 coding sequences, with 39.4% G+C content. The availability of this genome will facilitate the study of the pathogenicity of the Acinetobacter species.

12.
Clin Microbiol Infect ; 18(8): E273-82, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22524533

RESUMEN

Although the connection of microRNAs (miRNAs) to some diseases is well established, their involvement in chronic infections such as Helicobacter pylori has received less attention. The aim was to compare miRNA expression profiling in patients with duodenal ulcer (DU) due to H. pylori infection with that in infected patients without DU and in uninfected patients. The miRNA expression profile was determined by microarrays in antral mucosal samples from well-characterized dyspeptic patients (n = 46). The most significant set of miRNAs was subsequently analysed in an independent validation group of patients (n = 42). Transcripts for IL8, IL12p40, IL12p35 and IL23p19, the signalling molecules MYD88, GATA6, SOCS2 and STAT6 and H. pylori virulence factors cagA and VacA were analysed. Microarray experiments showed that 17 miRNAs were deregulated in the mucosa of H. pylori-infected patients. No significant differences were observed between normal and DU patients. PCR confirmed the up-regulation of miR-9, miR-146a, miR-155 and miR-650 and the down-regulation of miR-96 and miR-204 in the independent validation set of patients. Importantly, miR-9, miR-96, miR-146a and miR-650 expression was specific to chronic-active gastritis. H. pylori-infected patients showed higher levels of IL8 and IL12p40 mRNAs and lower levels of GATA6 and SOCS2 mRNAs. The antral mucosa of patients with non-active or chronic-active gastritis showed significantly lower levels of GATA6, MYD88, SOCS2 and STAT6 mRNAs compared with patients without gastritis. The down-regulation of these factors was not correlated with the expression of any of the validated miRNAs. The exact role of the miRNA changes observed will require further study.


Asunto(s)
Úlcera Duodenal/inmunología , Perfilación de la Expresión Génica , Infecciones por Helicobacter/inmunología , Helicobacter pylori/patogenicidad , Interacciones Huésped-Patógeno , MicroARNs/genética , Adulto , Úlcera Duodenal/microbiología , Femenino , Mucosa Gástrica/inmunología , Mucosa Gástrica/patología , Infecciones por Helicobacter/microbiología , Humanos , Masculino , Persona de Mediana Edad , Transducción de Señal/genética
13.
Tissue Antigens ; 71(3): 247-9, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18194365

RESUMEN

The functional (R620W) variant of human PTPN22 (protein tyrosine phosphatase non-receptor 22) gene has been implicated in the risk to several autoimmune disorders, including type 1 diabetes, Graves' disease, rheumatoid arthritis and systemic lupus erythematosus. In an association study of this single nucleotide polymorphism with celiac disease (CD), comparison of 262 young diagnosis patients and 214 adult controls from Spain showed a higher frequency of the minor allele in the CD group (9.7% vs 5.6% in controls; P = 0.018), suggestive of an increased genetic risk to the disease (odds ratio = 1.82; 95% confidence interval 1.1-3.0). These results support the role of PTPN22 as a general autoimmunity locus involved in tolerance induction in the thymus.


Asunto(s)
Enfermedad Celíaca/genética , Polimorfismo de Nucleótido Simple , Proteína Tirosina Fosfatasa no Receptora Tipo 22/genética , Adolescente , Adulto , Sustitución de Aminoácidos , Estudios de Casos y Controles , Enfermedad Celíaca/enzimología , Enfermedad Celíaca/inmunología , Niño , Preescolar , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Variación Genética , Genotipo , Humanos , Tolerancia Inmunológica/genética , Lactante , Masculino , Proteína Tirosina Fosfatasa no Receptora Tipo 22/inmunología , Factores de Riesgo , España
14.
Genes Immun ; 7(7): 550-4, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16929349

RESUMEN

The major susceptibility locus for type 1 diabetes mellitus (T1D) maps to the human lymphocyte antigen (HLA) class II region in the major histocompatibility complex on chromosome 6p21. In southern European populations, like the Basques, the greatest risk to T1D is associated with DR3 homo- and heterozygosity and is comparable to that of DR3/DR4, the highest risk genotype in northern European populations. Celiac disease (CD) is another DR3-associated autoimmune disorder showing certain overlap with T1D that has been explained by the involvement of common genetic determinants, a situation more frequent in DR3-rich populations, like the Basques. As both T1D- and CD-associated HLA alleles are part of conserved extended haplotypes (CEH), we compared DR3-homozygous T1D and CD patients to determine whether CEHs were equally distributed between both disorders or there was a differential contribution of different haplotypes. We observed a very pronounced distribution bias (P<10(-5)) of the two major DR3 CEHs, with DR3-B18 predominating in T1D and DR3-B8 in CD. Additionally, high-density single nucleotide polymorphism (SNP) analysis of the complete CEH [A*30-B*18-MICA*4-F1C30-DRB1*0301-DQB1*0201-DPB1*0202] revealed extraordinary conservation throughout the 4.9 Mbp analyzed supporting the existence of additional diabetogenic variants (other than HLA-DRB1*0301-DQB1*0201), conserved within the DR3-B18 CEH (but not in other DR3 haplotypes) that could explain its enhanced diabetogenicity.


Asunto(s)
Enfermedad Celíaca/genética , Enfermedad Celíaca/inmunología , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/inmunología , Antígeno HLA-DR3/genética , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Haplotipos , Homocigoto , Humanos , Masculino , Polimorfismo de Nucleótido Simple , España
15.
Antimicrob Agents Chemother ; 39(6): 1379-82, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7574536

RESUMEN

The OXA-7 gene, which encodes an oxacillinase, was cloned from plasmid pMG202 of Escherichia coli isolate 7181 (A. A. Medeiros, M. Cohenford, and G. A. Jacoby, Antimicrob. Agents Chemother. 27:715-719, 1985) and sequenced. The nucleotide sequence of the OXA-7 gene was closely related to that of the OXA-10 (PSE-2) gene, with a derived amino acid sequence of the OXA-7 enzyme showing greater than 95% homology with those of OXA-10 and OXA-11.


Asunto(s)
Genes Bacterianos , Plásmidos/análisis , beta-Lactamasas/genética , Secuencia de Aminoácidos , Secuencia de Bases , Mapeo Cromosómico , Elementos Transponibles de ADN , Datos de Secuencia Molecular , Alineación de Secuencia , Homología de Secuencia de Aminoácido
16.
Heredity (Edinb) ; 90(4): 316-25, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12692585

RESUMEN

Comparative sequencing of mitochondrial cytochrome b (Cyt b) and isoenzyme analyses have not resolved the population structure of the Iberian lineage of the sandfly Phlebotomus perniciosus, the most widespread vector of Leishmania infantum (Protozoa, Trypanosomatidae) to humans and dogs in the western Mediterranean subregion. Allelic variation at trinucleotide microsatellite loci was investigated in 13 Spanish populations of P. perniciosus. Four out of five loci showed significant differentiation between (pairwise F(ST)>0.23), but not within (pairwise F(ST)&<0.05), two regional groups of populations (southern and northeastern). All Cyt b sequences belonged to the Iberian lineage, which differs by six fixed nucleotide differences from the typical lineage found in northwest Africa, Malta and Italy. The northeastern group of Spanish populations had a reduced number of microsatellite alleles (16 out of the 29 present in the southern populations), indicating its derivation as a peripheral isolate following the species' dispersal from a southern Ice Age refuge 8000-12 000 years ago. Pairwise F(ST) values did not increase with geographical distance between populations, over distances of 246-850 km (between regions) and 16-491 km (within regions). This suggests that the two regional groups of populations remain isolated, but that within each region there are no significant permanent barriers to gene flow between contiguous populations. These findings will help to predict the capacity of this sandfly to disperse, and originate new foci of leishmaniasis, in response to climate warming.


Asunto(s)
Grupo Citocromo b/genética , Repeticiones de Microsatélite/genética , Phlebotomus/genética , Phlebotomus/fisiología , Animales , Cartilla de ADN , Frecuencia de los Genes , Genética de Población , Geografía , España
17.
Appl Environ Microbiol ; 66(5): 1933-8, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10788363

RESUMEN

A seminested PCR assay was developed in order to amplify the kinetoplast minicircle of Leishmania species from individual sand flies. The kinetoplast minicircle is an ideal target because it is present in 10,000 copies per cell and its sequence is known for most Leishmania species. The two-step PCR is carried out in a single tube using three primers, which were designed within the conserved area of the minicircle and contain conserved sequence blocks. The assay was able to detect as few as 3 parasites per individual sand fly and to amplify minicircle DNA from at least eight Leishmania species. This technique permits the processing of a large number of samples synchronously, as required for epidemiological studies, in order to study infection rates in sand fly populations and to identify potential insect vectors. Comparison of the sequences obtained from sand flies and mammal hosts will be crucial for developing hypotheses about the transmission cycles of Leishmania spp. in areas of endemicity.


Asunto(s)
ADN de Cinetoplasto/análisis , ADN Protozoario/análisis , Leishmania/aislamiento & purificación , Psychodidae/parasitología , Animales , ADN de Cinetoplasto/genética , ADN Protozoario/genética , Grecia , Humanos , Insectos Vectores , Leishmania/clasificación , Leishmania/genética , Leishmaniasis/transmisión , Mamíferos , Reacción en Cadena de la Polimerasa/métodos , Salud Urbana
18.
Insect Mol Biol ; 8(2): 179-84, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10380101

RESUMEN

A simple and reliable technique was developed to distinguish Phlebotomine sandflies by restriction fragment length polymorphism of PCR-amplified (PCR-RFLP) 18S rDNAs. Seven morphologically identified sandflies species from several localities of Greece and Cyprus were studied, and specific patterns were developed by double digesting amplified 18S rDNAs with HpaII and RsaI. Three additional species of the subgenus Larroussius were distinguished by a second double digestion with AccI and BanI. We have successfully applied the method on samples in which morphological characters were badly distinguished due to poor storage conditions and in larval stages.


Asunto(s)
ADN Ribosómico , Genes de Insecto , Polimorfismo Genético , Psychodidae/genética , ARN Ribosómico 18S , Animales , Chipre , Grecia , Polimorfismo de Longitud del Fragmento de Restricción , Psychodidae/clasificación
19.
Insect Mol Biol ; 9(2): 157-68, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10762423

RESUMEN

Relationships among seventy specimens, fifteen species and three genera of phlebotomines were inferred from the phylogenetic analysis of small subunit nuclear rDNA, obtained by the PCR amplification and cloning of almost full-length genes. Outgroups included fifteen dipterans, and single representatives of four other insect orders. The more distant the taxa compared, the larger were the regions of ambiguous sequence alignment that needed to be deleted in order to avoid circularity in performing parsimony analyses. Phlebotomine sequences formed a monophyletic clade within the suborder Nematocera, with the progressively more basal sister groups of Diptera being Culicomorpha, Tipulomorpha and the suborder Brachycera. Within Phlebotominae, subgeneric relationships were resolved and the genus Phlebotomus was shown to be monophyletic, but markers for intraspecific geographical populations were not found and intergeneric relationships were not resolved.


Asunto(s)
ADN Ribosómico/genética , Phlebotomus/clasificación , Psychodidae/clasificación , ARN Ribosómico 18S/genética , Animales , Secuencia de Consenso , Dípteros/clasificación , Dípteros/genética , Insectos/clasificación , Insectos/genética , Datos de Secuencia Molecular , Phlebotomus/genética , Reacción en Cadena de la Polimerasa , Psychodidae/genética , Análisis de Secuencia de ADN
20.
J Clin Lab Anal ; 14(2): 59-63, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10683615

RESUMEN

A total of 12 strains of Coxiella burnetii (8 Greek isolates from acute Q-fever patients, two reference strains-Nine Mile and Q212-and two pefloxacin-resistant laboratory strains) were examined for the presence of point mutations in the quinolone resistance determining region (QRDR) of gyrA gene by direct DNA sequencing of the polymerase chain reaction (PCR)-amplified fragments. The gene sequences of all eight Greek isolates and the two reference strains Nine Mile and Q212 [minimal inhibitory concentration (MIC)A) at the corresponding codon 87 of E. coli. This mutation lead to the substitution of Glu (codon GAG) by Lys (codon AAG ). Restriction maps of amplified gyrA gene sequences were determined by GCG Wisconsin PACKAGE, and the MnlI restriction enzyme was found to cut only the sensitive strains sequences and not the resistant ones. The present PCR-RFLP analysis has proved to be a simple, rapid, and useful method for the detection of Coxiella burnetii and, at the same time, for the diagnosis of quinolone-resistant Coxiella burnetii strains.


Asunto(s)
Coxiella burnetii/genética , Farmacorresistencia Microbiana , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Fiebre Q/microbiología , Quinolonas/farmacología , Secuencia de Aminoácidos , Secuencia de Bases , Coxiella burnetii/clasificación , Girasa de ADN , ADN-Topoisomerasas de Tipo II/química , ADN-Topoisomerasas de Tipo II/genética , ADN Bacteriano/química , Desoxirribonucleasas de Localización Especificada Tipo II , Farmacorresistencia Microbiana/genética , Grecia , Humanos , Datos de Secuencia Molecular , Pefloxacina/farmacología , Mutación Puntual , Análisis de Secuencia de ADN
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA