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1.
Klin Oczna ; 112(10-12): 321-3, 2010.
Artículo en Polaco | MEDLINE | ID: mdl-21473084

RESUMEN

The current paper presents a case of 14 months old girl with WAGR's syndrome. This syndrome is a genetic disorder characterized by the deletion at 11p13 locus which gives clinical presentation of aniridia, Wilms' tumor, genitourinary anomalies and mental retardation. Although WAGR's syndrome is a rare disorder, knowledge of its presentation is helpful in early diagnosis of nephroblastoma and may have impact on clinical outcome of the patient. Since aniridia may be the first symptom of WAGR's syndrome, it is recommended that all neonates with aniridia need to be screened for deletion of WT1 on chromosome 11p13. These with deletions should be monitored regularly for tumor development.


Asunto(s)
Síndrome WAGR/diagnóstico , Síndrome WAGR/terapia , Femenino , Humanos , Lactante , Resultado del Tratamiento
2.
Microbiology (Reading) ; 153(Pt 8): 2733-2742, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17660437

RESUMEN

Display of heterologous proteins on the surface of micro-organisms has become an increasingly used strategy for a range of applications in microbiology, biotechnology and vaccinology. In this study, the potential of the major structural protein DraE of Escherichia coli Dr fimbriae as a display system for heterologous sequences was tested. One copy of a heterologous sequence mimicking a small P(k) epitope of simian virus 5 was inserted into the draE gene, replacing the N-terminal region of the surface-exposed domain 2 as previously done with the glycoprotein D of herpes simplex virus type 1. The exposure of chimeric proteins on the bacterial surface was detected by immunofluorescence microscopy. Insertion of the heterogenic peptides had no detectable effect on the Ig-barrel structure of the DraE fimbrial subunits, as confirmed by FTIR spectroscopy. Additionally, the affinity of the chimeric fimbriae for DAF and type IV collagen was similar to that of the wild-type Dr fimbriae.


Asunto(s)
Colágeno/metabolismo , Escherichia coli/metabolismo , Receptores Inmunológicos/metabolismo , Adhesinas Bacterianas/química , Adhesinas Bacterianas/genética , Adhesinas Bacterianas/metabolismo , Adhesinas de Escherichia coli/química , Adhesinas de Escherichia coli/genética , Adhesinas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Modelos Moleculares , Virus de la Parainfluenza 5/genética , Estructura Terciaria de Proteína , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier
3.
Acta Crystallogr D Biol Crystallogr ; 62(Pt 2): 157-64, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16421447

RESUMEN

The dra gene cluster of uropathogenic strains of Escherichia coli produces proteins involved in bacterial attachment to and invasion of the eukaryotic host tissues. The crystal structure of a construct of E. coli DraD possessing an additional C-terminal extension of 13 amino acids, including a His6 tag, has been solved at a resolution of 1.05 angstroms. The protein forms symmetric dimers through the exchange of the C-terminal beta-strands, which participate in the immunoglobulin-like beta-sandwich fold of each subunit. This structure confirms that DraD is able to act as an acceptor in the donor-strand complementation mechanism of fiber formation but, in contrast to DraE adhesin, its native sequence does not have a donor strand; therefore, DraD can only be located at the tip of the fiber.


Asunto(s)
Adhesinas de Escherichia coli/química , Proteínas de Escherichia coli/química , Escherichia coli/química , Secuencia de Aminoácidos , Cristalografía por Rayos X , Dimerización , Escherichia coli/patogenicidad , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/aislamiento & purificación , Prueba de Complementación Genética , Histidina/química , Inmunoglobulinas/química , Datos de Secuencia Molecular , Oligopéptidos/química , Conformación Proteica
4.
Acta Biochim Pol ; 52(3): 639-46, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16175239

RESUMEN

The chaperone-usher system determines the biogenesis of surface-exposed adhesive structures responsible for virulence of many Gram-negative bacteria. Investigations of the last 20 years have resolved the mechanism of this pathway on a structural level for different species of pathogenic bacteria. The purpose of this review is to present the molecular mechanisms of the biogenesis of adhesive structures assembled via the chaperone-usher pathway. The obtained mechanistic data allow one to propose potential strategies of anti-bacterial action. Additionally, the specific properties of the polymeric adhesive structures (pili and fimbriae) of the chaperone-usher system allow their use as effective and safe recombinant vaccines carrying foreign epitopes in thousands of copies on bacterial cell surface.


Asunto(s)
Antibacterianos/química , Proteínas Bacterianas/metabolismo , Vacunas Bacterianas/química , Diseño de Fármacos , Chaperonas Moleculares/metabolismo , Adhesinas Bacterianas/metabolismo , Antibacterianos/farmacología , Infecciones Bacterianas/prevención & control , Proteínas Bacterianas/química , Vacunas Bacterianas/administración & dosificación , Membrana Celular/metabolismo , Epítopos/inmunología , Proteínas Fimbrias/química , Proteínas Fimbrias/metabolismo , Fimbrias Bacterianas/química , Fimbrias Bacterianas/metabolismo , Pruebas de Sensibilidad Microbiana , Chaperonas Moleculares/química
5.
Przegl Lek ; 62(3): 169-72, 2005.
Artículo en Polaco | MEDLINE | ID: mdl-16171148

RESUMEN

Epidemiological studies point out steady increase of the incidence of cancer disease in Poland and all over the world. Neoplasms are associated with blood coagulation disorders very frequently. The investigations concentrate on searching for the substance producing malignant cells and causing activation of blood coagulation in neoplasm disease patients. Gordon and co-workers were the first who published results of their investigation in searching for such a substance in 1975. It was isolated from the rabbit's neoplasm type V2 Ca and then characterized and named as cancer procoagulant (CP). Cancer procoagulant is responsible for blood coagulation disorders in neoplasm disease patients, incorrect metabolism of fibrin and its concentration around malignant tissues. This enzyme (in vitro) is a direct activator of the factor X, without contribution of factor VII or any other cofactors. CF differs in physical, chemical and enzymatic activity from others procoagulants. The main aim of the paper is a review of the literature for structure, chemical characteristic, occurrence and clinical relevance of the cancer procoagulant (CP) and its clinical use in current oncological diagnostics.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Cisteína Endopeptidasas/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/enzimología , Animales , Humanos
6.
Microbiology (Reading) ; 151(Pt 7): 2477-2486, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16000738

RESUMEN

The dra gene cluster, expressed by uropathogenic Escherichia coli strains, determines bacterial attachment and invasion. The Dr fimbrial structures formed at the bacterial cell surface are composed of DraE subunits. The Dr fimbriae-coding cluster contains six open reading frames--draA, draB, draC, draD, draP and draE--among which the draE gene encodes the structural fimbrial subunit DraE. Very little is known about E. coli surface expression of the draD gene product. The expression of DraD and its role in the biogenesis of Dr fimbriae were determined by constructing mutants in the dra operon and by immunoblot and immunofluorescence experiments. In this study, DraD was found to be a surface-exposed protein. The expression of DraD was independent of the DraC usher and DraE fimbrial subunits. Polymerization of DraE fimbrial subunits into fimbrial structures did not require expression of the DraD protein.


Asunto(s)
Adhesinas Bacterianas/fisiología , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Fimbrias Bacterianas/metabolismo , Adhesinas Bacterianas/química , Adhesinas Bacterianas/metabolismo , Adhesinas de Escherichia coli/análisis , Adhesinas de Escherichia coli/genética , Adhesinas de Escherichia coli/metabolismo , Escherichia coli/genética , Escherichia coli/patogenicidad , Proteínas de Escherichia coli/química , Datos de Secuencia Molecular
7.
Med Wieku Rozwoj ; 9(4): 727-39, 2005.
Artículo en Polaco | MEDLINE | ID: mdl-16733281

RESUMEN

UNLABELLED: The most frequent etiological factor of urinary tract infections are virulent Escherichia coli strains. Identification of uropathogenic Escherichia coli strains is possible using biomolecular techniques. THE PURPOSE OF THIS STUDY was to determine the prevalence of Escherichia coli strains encoding papG adhesins and adhesins of Dr family in children with urinary tract infections and to establish the relationship between the bacterial genotype and clinical course of a sickness. MATERIAL AND METHODS: In 163 children with urinary tract infection caused by Escherichia coli strains, after taking history and physical examination, inflammatory parameters were determined. In all patients abdominal ultrasonography and in chosen patients -- miction cystourethrography and urodynamic examinations were performed. In order to identify Escherichia coli strains possessing pap gene cluster class I, II and III (encoding P fimbriae) and genes encoding Dr family of adhesins, the Polymerase Chain Reaction was used. RESULTS AND CONCLUSIONS: From all isolated Escherichia coli strains, pap gene cluster was identified in 41.1% and dra gene cluster in 42.3%. Escherichia coli strains encoding papG gene class II frequently caused upper urinary tract injections, while strains encoding papG gene class III and genes encoding adhesins of Dr family were mostly responsible for lower urinary tract infections and their recurrences. Occurrence of virulent Escherichia coli strains was not more common in children with pyelonephritis and with disorders of urinary tract in comparison with the group of children without urinary tract anomalies. Determination of bacterial virulence factors causing urinary tract infections in children may be helpful in the prognosis of the course of the disease.


Asunto(s)
Adhesinas de Escherichia coli/genética , Infecciones por Escherichia coli/microbiología , Escherichia coli/genética , Escherichia coli/patogenicidad , Proteínas Fimbrias/genética , Infecciones Urinarias/microbiología , Adolescente , Adhesión Bacteriana , Niño , Preescolar , Escherichia coli/clasificación , Femenino , Humanos , Lactante , Masculino , Reacción en Cadena de la Polimerasa , Especificidad de la Especie , Virulencia
8.
Infect Immun ; 73(1): 135-45, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15618148

RESUMEN

The Dr hemagglutinin of uropathogenic Escherichia coli is a fimbrial homopolymer of DraE subunits encoded by the dra operon. The dra operon includes the draB and draC genes, whose products exhibit homology to chaperone-usher proteins involved in the biogenesis of surface-located polymeric structures. DraB is one of the periplasmic proteins belonging to the superfamily of PapD-like chaperones. It possesses two conserved cysteine residues characteristic of the FGL subfamily of Caf1M-like chaperones. In this study we obtained evidence that DraB cysteines form a disulfide bond in a mature chaperone and have the crucial function of forming the DraB-DraE binary complex. Expression experiments showed that the DraB protein is indispensable in the folding of the DraE subunit to a form capable of polymerization. Accumulation of DraB-DraE(n) oligomers, composed of head-to-tail subunits and the chaperone DraB, was observed in the periplasm of a recombinant E. coli strain which expressed DraB and DraE (but not DraC). To investigate the donor strand exchange mechanism during the formation of DraE oligomers, we constructed a series of DraE N-terminal deletion mutants. Deletion of the first three N-terminal residues of a potential donor strand resulted in a DraE protein lacking an oligomerization function. In vitro data showed that the DraE disulfide bond was not needed to form a binary complex with the DraB chaperone but was essential in the polymerization process. Our data suggest that assembly of Dr fimbriae requires a chaperone-usher pathway and the donor strand exchange mechanism.


Asunto(s)
Adhesinas Bacterianas/fisiología , Proteínas de Escherichia coli/fisiología , Fimbrias Bacterianas/fisiología , Chaperonas Moleculares/fisiología , Proteínas Periplasmáticas/fisiología , Adhesinas Bacterianas/química , Secuencia de Aminoácidos , Disulfuros , Proteínas de Escherichia coli/química , Chaperonas Moleculares/química , Datos de Secuencia Molecular , Proteínas Periplasmáticas/química , Subunidades de Proteína
9.
Ginekol Pol ; 75(9): 705-12, 2004 Sep.
Artículo en Polaco | MEDLINE | ID: mdl-15600294

RESUMEN

OBJECTIVES: Cancer procoagulant (CP) is a sulfhydryl proteinase thought to be synthesized mainly by neoplastic cells. Consequently, increased CP activity in blood serum was interpreted as being associated with the presence of a proliferative process in the host's body. To date, CP activity has not been systematically studied in cases of genital carcinoma. The present study is aimed at evaluation of CP activity in women with genital carcinoma. DESIGN: A case-controlled study backed up by histopathological examination. MATERIALS AND METHODS: Peripheral blood was sampled preoperatively in a sterile manner from an antecubital vein, from 16 women with cervical carcinoma and 15 women with uterine carcinoma. Blood for the reference group of 12 healthy women was obtained in an identical manner after an overnight fast. The CP activity in serum was determined using the coagulative method according to Gordon and Benson, and was expressed as coagulation time in seconds (s). The CP activity in 10% tissue homogenates (in saline) of genital cancer was determined by the chromogenic method according to Colucci et al. RESULTS: The mean CP activity in serum of women with cervical carcinoma (78.28 +/- 15.25 s) and of women with uterine carcinoma (79.63 +/- 12.02 s) was significantly different (P < 0.0001) from the respective values found in healthy women (281.33 +/- 43.19 s). The CP activity in neoplastic tissue was 28.50 +/- 6.40 nmol pNa/mL for cervical carcinoma, and 28.31 +/- 3.92 nmol pNa/mL for uterine carcinoma, both values being significantly higher (P < 0.0009) than the activity found in the normal tissues. There was no established relationship between neoplastic CP activity and FIGO staging of the disease. CONCLUSIONS: This is the first study to demonstrate the concomitant presence of CP activity in serum and neoplastic tissue of women with genital carcinoma. These patients have decreased coagulation time and thus are likely to develop coagulation disturbances in the course of their cancer. There may be a role for CP as a tumor marker of genital carcinoma.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Cisteína Endopeptidasas/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/patología , Neoplasias Uterinas/metabolismo , Neoplasias Uterinas/patología , Adulto , Anciano , Biomarcadores de Tumor/sangre , Estudios de Casos y Controles , Cisteína Endopeptidasas/sangre , Femenino , Humanos , Persona de Mediana Edad , Proteínas de Neoplasias/sangre , Estadificación de Neoplasias , Factores de Riesgo , Factores de Tiempo , Neoplasias del Cuello Uterino/sangre , Neoplasias Uterinas/sangre
11.
Infect Immun ; 71(10): 5505-13, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14500468

RESUMEN

The potential of the major structural protein DraE of Escherichia coli Dr fimbriae has been used to display an 11-amino-acid peptide of glycoprotein D derived from herpes simplex virus (HSV) type 1. The heterologous sequence mimicking an epitope from glycoprotein D was inserted in one copy into the draE gene in place of a predicted 11-amino-acid sequence in the N-terminal region of surface-exposed domain 2 within the conserved disulfide loop (from Cys21 to Cys53). The inserted epitope was displayed on the surface of the chimeric DraE protein as evidenced by immunofluorescence and was recognized by monoclonal antibodies to the target HSV glycoprotein D antigen. Conversely, immunization of rabbits with purified chimeric Dr-HSV fimbriae resulted in a serum that specifically recognized the 11-amino-acid epitope of HSV glycoprotein D, indicating the utility of the strategy employed.


Asunto(s)
Herpesvirus Humano 1/genética , Herpesvirus Humano 1/inmunología , Vacunas Sintéticas/genética , Vacunas Sintéticas/inmunología , Proteínas del Envoltorio Viral/genética , Proteínas del Envoltorio Viral/inmunología , Adhesinas Bacterianas/genética , Adhesinas Bacterianas/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales , Antígenos Virales/genética , Secuencia de Bases , ADN Recombinante/genética , Epítopos/genética , Escherichia coli/genética , Escherichia coli/inmunología , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/inmunología , Fimbrias Bacterianas/genética , Fimbrias Bacterianas/inmunología , Vacunas contra Herpesvirus/genética , Vacunas contra Herpesvirus/inmunología , Humanos , Técnicas In Vitro , Modelos Inmunológicos , Biblioteca de Péptidos , Conejos , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología
12.
Med Wieku Rozwoj ; 7(3): 359-67, 2003.
Artículo en Polaco | MEDLINE | ID: mdl-14963343

RESUMEN

The aim of our study was to measure renal function and growth in survivors of unilateral Wilms' tumour in 21 children and young adults (7 female). The mean age was 12.6 +/- 4.8 years, mean follow-up time was 7.01 +/- 4.25 years: seven of the group received irradiation (35 Gy). Blood pressure was normal in all patients. Three of them had elevated cystatin C and clearance of cystatin C below referenced normal value. The others had normal renal function tests (cystatin C, creatinine and cystatin clearance, B2 microglobulin, microalbuminuria, osmolality). Compared to the control we found higher cystatin C values in children treated before the age 3 years old (p=0.03) and in children treated more than 5 years before (p=0.03), and lower cystatin clearance in group treated before the age 3 years old (p=0,03). No difference between the irradiated and non-irradiated group was found. We observed a greater increase in volume (155.9% +/- 33.4) than in length (127.9% +/- 6.3). The highest rise of renal volume was in children treated more than 5 years before (174.6% +/- 22.3). In conclusion, our data suggest that after combined treatment for Wilms' tumour compensatory renal hypertrophy and a tendency progressive renal dysfunction takes place.


Asunto(s)
Pruebas de Función Renal , Neoplasias Renales/fisiopatología , Riñón/fisiopatología , Tumor de Wilms/fisiopatología , Adolescente , Adulto , Albuminuria/etiología , Estudios de Casos y Controles , Niño , Preescolar , Creatinina/sangre , Cistatina C , Cistatinas/sangre , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Renales/complicaciones , Neoplasias Renales/terapia , Masculino , Concentración Osmolar , Tumor de Wilms/complicaciones , Tumor de Wilms/terapia , Microglobulina beta-2/sangre
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