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1.
Gynecol Obstet Fertil Senol ; 45(10): 535-544, 2017 Oct.
Artículo en Francés | MEDLINE | ID: mdl-28939364

RESUMEN

OBJECTIVES: The aim of this study was to evaluate the impact of pathological complete response (pCR) on overall survival (OS) and recurrence-free survival (RFS) according to molecular subtypes in women treated for an invasive breast cancer after neoadjuvant chemotherapy (NAC). METHODS: All women (n=225) managed with a neoadjuvant chemotherapy for an invasive breast cancer in our institution between January 2007 and December 2013 were included. The characteristics of patients with pCR (pCR-1), breast pCR and axillary pCR were compared to those without pCR (pCR-0) according to the molecular subtypes: luminal A (n=62), luminal B (n=77), Her-2 (n=31) and triple negative (n=55). RESULTS: NAC concerned 225 patients of whom 36 (16%) had pCR. Achievement of pCR led to significantly better overall survival in women with Her-2 tumors (35% versus 100%, P=0.035) and also to significantly better locoregional survival in women treated for triple negative tumors (P=0.026). Predictive factors of pCR were a high pathologic grade: OR=2.39, IC 95% (1.19-4.83), P=0.008; Her-2 molecular subtype (P=0.008); positive estrogenic hormonal receptors (P=0.006), a positive Her-2 receptor: OR=2.58, IC 95% (1.20-5.54), P=0.01. CONCLUSION: Achievement of pCR is an intermediate marker of survival in women managed with NAC for breast cancer.


Asunto(s)
Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Quimioterapia Adyuvante/estadística & datos numéricos , Terapia Neoadyuvante/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Axila , Neoplasias de la Mama/clasificación , Femenino , Humanos , Ganglios Linfáticos/patología , Mastectomía , Persona de Mediana Edad , Invasividad Neoplásica/patología , Receptor ErbB-2/análisis , Receptores de Estrógenos/análisis , Receptores de Progesterona/análisis , Resultado del Tratamiento
2.
Gynecol Obstet Fertil Senol ; 45(9): 466-471, 2017 Sep.
Artículo en Francés | MEDLINE | ID: mdl-28869182

RESUMEN

OBJECTIVES: The aim of our study was to evaluate the existence of predictive factors of conservative breast surgery after neoadjuvant chemotherapy (NAC) for breast cancer. METHODS: We included all women with invasive breast cancer who received NAC and underwent breast surgery between January 2007 and December 2013 in our institution. Univariable and multivariable analyses were performed to determine the association between clinical and histological factors and conservative breast surgery. RESULTS: During the study period, 229 women were included of whom 73 had breast conservative surgery (32%). At univariable analysis, significant predictive factors were age (OR 0.97 [CI 95% 0.95-0.99], P=0.02), radiological size (OR 0.97 [CI 95% 0.96-0.99], P<0.001), multifocality (OR 0.53 [CI 95% 0.27-1.05], P=0.06), breast inflammation (OR 0.15 [CI 95% 0.07-0.32], P<0.001) and the type of hormone receptors (P=0.12). In multivariable analysis, all these factors but age were significant factors and thus considered as independent predictive factors. CONCLUSION: This work permitted to identify independent predictive factors of breast conservative surgery after NAC for breast cancer that will be included in a risk scoring system that we aim to evaluate prospectively.


Asunto(s)
Neoplasias de la Mama/cirugía , Mastectomía Segmentaria , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/tratamiento farmacológico , Quimioterapia Adyuvante , Femenino , Predicción , Humanos , Persona de Mediana Edad , Terapia Neoadyuvante , Estudios Retrospectivos , Adulto Joven
3.
Gynecol Obstet Fertil Senol ; 45(4): 215-223, 2017 Apr.
Artículo en Francés | MEDLINE | ID: mdl-28359803

RESUMEN

OBJECTIVE: The aim of this study was to evaluate outcomes of patients with breast cancer in function of the body mass index (BMI). METHODS: The study cohort consisted of consecutive women undergoing surgery for breast cancer in our institution between January 2009, and September 2013. Individual records of all patients were reviewed and analyzed. Patient BMI was categorized as underweight, normal, overweight and obese. RESULTS: A total of 1599 patients were evaluated. Patients were followed for one to 265months with a mean of 36.4months. The number of patients in each of the BMI categories was 66, 779, 463 and 291 for underweight, normal, overweight and obese women respectively. Women with higher BMI were more frequently affected by hypertension (18, 21, 35 and 47% respectively, P<0.0001) and diabetes (3, 2, 7 and 7% respectively, P<0.0001). Obese women had more frequently an inflammatory presentation (P=0.006), larger tumour size (P=0.038) and axillary lymph node involvement (P=0.03) with much more positive lymph nodes (P=0.02). Patients had the same protocols of treatment (surgery and adjuvant treatment). There was no statistically significant difference in overall 5-years survival between groups (P=0.30). CONCLUSIONS: Our study demonstrate a more aggressive clinical and histological presentation for obese women with breast cancer.


Asunto(s)
Índice de Masa Corporal , Neoplasias de la Mama/cirugía , Resultado del Tratamiento , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/patología , Femenino , Humanos , Hipertensión/complicaciones , Inflamación/complicaciones , Metástasis Linfática/patología , Persona de Mediana Edad , Obesidad/complicaciones , Sobrepeso/complicaciones , Tasa de Supervivencia , Delgadez/complicaciones
4.
Eur J Pharm Biopharm ; 96: 396-408, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26386355

RESUMEN

A polymer based material was developed to act as an embolic agent and drug reservoir for the treatment of arteriovenous malformations (AVM) and hyper vascularized solid tumors. The aim was to combine the blocking of blood supply to the target region and the inhibition of the embolization-stimulated angiogenesis. The material is composed of an ethanolic solution of a linear acrylate based copolymer and acrylate calibrated microparticles containing nanospheres loaded with sunitinib, an anti-angiogenic agent. The precipitation of the linear copolymer in aqueous environment after injection through microcatheter results in the formation of an in-situ embolization gel whereas the microparticles serve to increase the cohesive properties of the embolization agent and to form a reservoir from which the sunitinib-loaded nanospheres are released post-embolization. The swollen state of the microparticles in contact with aqueous medium results in the release of the nanospheres out of microparticles macromolecular structure. After the synthesis, the formulation and the characterization of the different components of the material, anti-angiogenic activity was evaluated in vitro using endothelial cells and in vivo using corneal neovascularization model in rabbit. The efficiency of the arterial embolization was tested in vivo in a sheep model. Results proved the feasibility of this new system for vascular embolization in association with an in situ delivery of anti-angiogenic drug. This combination is a promising strategy for the management of arteriovenous malformations and solid tumors.


Asunto(s)
Inhibidores de la Angiogénesis/administración & dosificación , Sistemas de Liberación de Medicamentos , Embolización Terapéutica , Endotelio Vascular/efectos de los fármacos , Indoles/administración & dosificación , Nanosferas/química , Neovascularización Patológica/prevención & control , Pirroles/administración & dosificación , Acrilatos/efectos adversos , Acrilatos/química , Inhibidores de la Angiogénesis/efectos adversos , Inhibidores de la Angiogénesis/farmacología , Inhibidores de la Angiogénesis/uso terapéutico , Animales , Malformaciones Arteriovenosas/tratamiento farmacológico , Materiales Biocompatibles/efectos adversos , Materiales Biocompatibles/química , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Córnea/irrigación sanguínea , Córnea/efectos de los fármacos , Córnea/patología , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/efectos adversos , Preparaciones de Acción Retardada/farmacología , Preparaciones de Acción Retardada/uso terapéutico , Composición de Medicamentos , Sistemas de Liberación de Medicamentos/efectos adversos , Embolización Terapéutica/efectos adversos , Endotelio Vascular/citología , Endotelio Vascular/patología , Geles , Células Endoteliales de la Vena Umbilical Humana/citología , Indoles/efectos adversos , Indoles/farmacología , Indoles/uso terapéutico , Músculos Intercostales/irrigación sanguínea , Músculos Intercostales/efectos de los fármacos , Músculos Intercostales/patología , Nanosferas/efectos adversos , Neovascularización Patológica/patología , Pirroles/efectos adversos , Pirroles/farmacología , Pirroles/uso terapéutico , Conejos , Distribución Aleatoria , Oveja Doméstica , Sunitinib
5.
J Gynecol Obstet Biol Reprod (Paris) ; 44(2): 171-5, 2015 Feb.
Artículo en Francés | MEDLINE | ID: mdl-24975399

RESUMEN

AIM: To evaluate efficiency of Bakri balloon tamponade (BB) to stop severe post-partum haemorrhage (PPH) and fertility outcomes. METHODS: Retrospective study including all patients who underwent Bakri balloon tamponade for severe PPH between January 2009 and December 2013. The objectives were to stop PPH by BB and to evaluate the fertility after Bakri balloon tamponade. RESULTS: Sixty-one women had a Bakri balloon inserted in utero for severe PPH. The PPH was stopped in 55 patients out of 61 (88%). The reasons of severe PPH were uterine atony in 44 cases (72%), placental retention in 10 cases, placenta praevia in 3 cases, and cervical or vaginal tears in 4 cases. In one third of cases, the pregnancy was complicated by diabetes, placenta praevia, hypertensive troubles. A cesarean section or an instrumental delivery was performed for one third of patients. The mean duration of the Bakri balloon insertion was of 7 hours [5-9] and the mean filling of the balloon was of 350 ml [205-450]. The mean blood loss was of 1600 [1200-2250]. Sixty-three percent of patients (n=38) received red blood cells transfusion. The BB was efficient after a vaginal delivery or after a caesarean section and in all cases of placenta praevia. In 6 cases, the BB was inefficient and uterine embolisation or a surgical procedure was performed to stop PPH. Nine women underwent a new pregnancy after the insertion of Bakri balloon for severe PPH and 3 delivered healthy newborns. CONCLUSION: Bakri balloon tamponade is a minimally invasive intrauterine device efficient to stop severe post-partum haemorrhage. New pregnancies and deliveries are possible after tamponade by Bakri balloon.


Asunto(s)
Fertilidad/fisiología , Hemorragia Posparto/terapia , Taponamiento Uterino con Balón/instrumentación , Transfusión Sanguínea/estadística & datos numéricos , Parto Obstétrico/efectos adversos , Parto Obstétrico/métodos , Parto Obstétrico/estadística & datos numéricos , Femenino , Humanos , Recién Nacido , Paridad , Hemorragia Posparto/epidemiología , Hemorragia Posparto/etiología , Embarazo , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Taponamiento Uterino con Balón/métodos
6.
Geobiology ; 12(4): 289-307, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24690273

RESUMEN

Most foraminifera that produce a shell are efficient biomineralizers. We analyzed the calcitic shell of the large tropical benthic foraminifer Schlumbergerella floresiana. We found a suite of macromolecules containing many charged and polar amino acids and glycine that are also abundant in biomineralization proteins of other phyla. As neither genomic nor transcriptomic data are available for foraminiferal biomineralization yet, de novo-generated sequences, obtained from organic matrices submitted to ms blast database search, led to the characterization of 156 peptides. Very few homologous proteins were matched in the proteomic database, implying that the peptides are derived from unknown proteins present in the foraminiferal organic matrices. The amino acid distribution of these peptides was queried against the uniprot database and the mollusk uniprot database for comparison. The mollusks compose a well-studied phylum that yield a large variety of biomineralization proteins. These results showed that proteins extracted from S. floresiana shells contained sequences enriched with glycine, alanine, and proline, making a set of residues that provided a signature unique to foraminifera. Three of the de novo peptides exhibited sequence similarities to peptides found in proteins such as pre-collagen-P and a group of P-type ATPases including a calcium-transporting ATPase. Surprisingly, the peptide that was most similar to the collagen-like protein was a glycine-rich peptide reported from the test and spine proteome of sea urchin. The molecules, identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry analyses, included acid-soluble N-glycoproteins with its sugar moieties represented by high-mannose-type glycans and carbohydrates. Describing the nature of the proteins, and associated molecules in the skeletal structure of living foraminifera, can elucidate the biomineralization mechanisms of these major carbonate producers in marine ecosystems. As fossil foraminifera provide important paleoenvironmental and paleoclimatic information, a better understanding of biomineralization in these organisms will have far-reaching impacts.


Asunto(s)
Calcificación Fisiológica , Carbonatos/metabolismo , Foraminíferos/metabolismo , Secuencia de Aminoácidos , Aminoácidos/análisis , Electroforesis en Gel de Poliacrilamida , Foraminíferos/química , Datos de Secuencia Molecular , Monosacáridos/análisis
7.
Biomaterials ; 28(12): 2155-62, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17258312

RESUMEN

Osteoclast activity was studied on nacre, the mother of pearl (MOP) in order to assess the plasticity of bone resorbing cells and their capacity to adapt to a biomineralized material with a different organic and mineral composition from that of its natural substrate, bone. Pure MOP, a natural biomineralized CaCO(3) material, was obtained from Pinctada oyster shell. When implanted in the living system, nacre has proven to be a sustainable bone grafting material although a limited surface degradation process. Osteoclast stem cells and mature osteoclasts were cultured on MOP substrate and osteoclast precursor cells were shown to differentiate into osteoclasts capable of resorbing nacre substrate. However, analysis of the organization of the cytoskeleton showed that both a sealing zone and a podosome structure were observed on the nacre substrate. Moreover, MOP resorption efficiency was consistently found to be lower than that of bone and appeared to be a limited process.


Asunto(s)
Carbonato de Calcio/química , Osteoclastos/citología , Animales , Adhesión Celular , Células Cultivadas , Citoesqueleto/ultraestructura , Humanos , Microscopía Electrónica de Rastreo , Conejos
8.
FEBS Lett ; 580(10): 2435-41, 2006 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-16638568

RESUMEN

Nacre or mother-of-pearl in the shell of Pinctada margaritifera is composed of 95-99% calcium carbonate and 1-5% organic matrix. In this study, we developed an original technique to characterize the genes differentially expressed in nacre-forming cells (NFC) by combining suppression subtractive hybridization (SSH), to establish a cDNA subtractive library, with rapid amplification of cDNA ends (RACE)-PCR. Seventy-two specific cDNA sequences have been obtained so far. These include a protein containing two EF-hand Ca2+-binding domains which was completely sequenced after amplification by RACE-PCR. Its specific expression as well as the specificity of the SSH method was confirmed by semi-quantitative RT-PCR on NFC and mantle cells.


Asunto(s)
Proteínas de Unión al Calcio/química , Pinctada/química , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Proteínas de Unión al Calcio/genética , ADN Complementario , Expresión Génica , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Aminoácido
9.
Biotechnol Lett ; 27(1): 33-40, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15685417

RESUMEN

Esterified acid soluble pectins from flax (Linun usitatissimum L.) were degraded either with HCl or pectin lyase. Centrifugation and 2-propanol precipitation led to the isolation of two low molecular weight polygalacturonates after acid hydrolysis of pectins. However, after pectin lyase digestion and purification by size-exclusion HPLC, (1)H NMR analyses indicated that acetylated hairy regions, large methylated and acetylated oligogalacturonides together with small unsubstituted oligogalacturonides were produced. Thus, in a few steps, a panel of substituted neutral and acidic oligosaccharides was produced from a raw plant material. Such oligosaccharides could be useful for further fractionations such as chemical saponification and enzymatic removal of neutral sugar chains from the hairy regions. The procedures used for pectin extraction, for degradation, and for the purification of fragments seem appropriate for large-scale production of biologically active oligosaccharides from flax.


Asunto(s)
Lino/química , Oligosacáridos/síntesis química , Pectinas/química , Acetilación , Cromatografía Líquida de Alta Presión , Ácido Clorhídrico/química , Espectroscopía de Resonancia Magnética , Metilación , Pectinas/metabolismo , Polisacárido Liasas/metabolismo
10.
Comp Biochem Physiol B Biochem Mol Biol ; 128(3): 389-400, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11250534

RESUMEN

Several proteins from nacre of the oyster Pinctada maxima and the abalone Haliotis tuberculata were extracted and partly characterized. Proteins dispersed in aragonite were solubilized during demineralization with acetic acid whereas proteins adsorbed on conchiolin were extracted with sodium dodecyl sulfate and beta-mercaptoethanol. The matrix of Pinctada maxima nacre is composed of one main protein with an apparent molecular weight of 20 kDa (p20). This protein was found in the acetic acid soluble fraction of nacre, as well as in the Laemmli-solubilized extract of conchiolin. In addition, the p20 solubilized with acetic acid can form oligomers made of 6 monomers linked together by disulfide bridges. The first N-terminal 21 amino acids of p20 were determined and no homology with known proteins was found. In Haliotis tuberculata nacre, 5 main proteins were solubilized during demineralization and 3 glycoproteins were detected. Stains-all and Alcian blue staining revealed polyanionic proteins in the extracts isolated from Pinctada maxima and Haliotis tuberculata nacre.


Asunto(s)
Glicoproteínas/aislamiento & purificación , Músculos/química , Ostreidae/química , Secuencia de Aminoácidos , Animales , Cromatografía Líquida de Alta Presión , Electroforesis en Gel de Poliacrilamida , Glicoproteínas/análisis , Datos de Secuencia Molecular , Peso Molecular , Solubilidad , Sulfatasas/farmacología , Tripsina/farmacología
11.
Biosci Rep ; 21(6): 839-55, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12166831

RESUMEN

Knowing that human blood monocyte-derived dendritic cells express cell-surface mannose-specific lectins, we prepared various mannoses containing glycoconjugates with the aim of developing highly specific synthetic carriers of oligonucleotides and genes. Conjugates were prepared from oligosaccharides obtained by hydrazinolysis of Saccharomyces cerevisiae invertase glycopeptides. The reducing saccharides were converted into glycosynthons, i.e., into glyco-amino acids. Fluorescein derivatives were obtained by coupling the free carboxyl group of oligosaccharyl-pyroglutamate to the alpha-amino group of epsilon-fluoresceinyl-thiocarbamyl lysine methyl ester. It has been shown by others that glycosylated linear oligolysines containing up to six alpha-D-mannopyranosylphenylthiocarbamyl units have a high affinity for the human mannose receptor. In order to obtain fully biodegradable clusters and to improve both the specificity and the selectivity, disaccharides transformed into glycosynthons were coupled to pentalysine carriers (Lys5-Ala-Cys-NH2). Glycosylated pentalysyl cysteine conjugates were made fluorescent upon substitution of the cysteine thiol group with fluorescein iodoacetamide. As shown by flow cytofluorimetry, both the dimannoside clusters and yeast oligomannosides were very efficiently taken up by DC, conversely lactoside clusters were not.


Asunto(s)
Células Dendríticas/metabolismo , Endocitosis/fisiología , Manósidos/metabolismo , Transporte Biológico , Células Dendríticas/citología , Citometría de Flujo , Colorantes Fluorescentes/metabolismo , Glicósido Hidrolasas/metabolismo , Humanos , Manósidos/química , Estructura Molecular , Oligopéptidos/metabolismo , Polisacáridos/química , Polisacáridos/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , beta-Fructofuranosidasa
12.
Mar Biotechnol (NY) ; 3(1): 36-44, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14961388

RESUMEN

This study was performed to characterize and quantify chitosan by simple physicochemical methods (infrared spectroscopy and potentiometric measurements). These procedures were validated with well-characterized chitosan before being used to investigate chitosan in nacre of the abalone Haliotis tuberculata and of the giant oyster Pinctada maxima. Potentiometric study revealed a chitosan extract from the nacre of H. tuberculata with a degree of deacetylation of around 88% and an intrinsic pK of 6.5. According to infrared and potentiometric data, a low yield (eta) of extraction was calculated (eta = 0.064%). For experiments performed on the nacre of P. maxima, and in spite of more stringent deacetylation conditions, results suggested that a chitin-protein complex (eta = 0.053%) was isolated rather than chitosan.

13.
Microbiol Immunol ; 43(1): 1-8, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10100740

RESUMEN

The purpose of this study was to sequence the central part of the coding region of the Clostridium tyrobutyricum fiagellin gene to improve the immunoenzymatic counting of cells after milk filtration. The coding region was amplified by PCR, and the amplified products were cloned. A DNA sequence analysis of positive clones gave us 1,131 nucleotides with a partial calculated flagellin molecular mass of 40,143 Da. The flagellar filament protein sequence exhibited high levels of homology to sequences of flagellin protein from other bacteria in both N- and C-terminal parts, but little homology in the central domain. A PCR-restriction fragment length polymorphism analysis of amplified C. tyrobutyricum flagellin gene products confirmed the variability of the central domain. The flagellin mRNA was determined to be 1.1 kb in size, which suggests a monocistronic mRNA. Furthermore, the deduced protein flagellin contains eleven potential N-glycosylation sites and one sequence rich in serine, which could be modified by O-glycosylation.


Asunto(s)
Clostridium/genética , Flagelina/genética , Genes Bacterianos , Secuencia de Aminoácidos , Secuencia de Bases , Northern Blotting , Clonación Molecular , Clostridium/clasificación , Cartilla de ADN , Flagelina/metabolismo , Glicosilación , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo de Longitud del Fragmento de Restricción , Análisis de Secuencia de ADN
14.
Microbios ; 94(379): 183-92, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9853380

RESUMEN

Glycosylation analysis of the flagellin from the Gram-positive species Clostridium tyrobutyricum has been supplemented. Amino acid analysis of the glycopeptides obtained after pronase digestion of flagellin indicated that O-glycosylation which was previously demonstrated after nonreductive beta-elimination, probably occurred via the hydroxyl group of serine. Otherwise, beta-elimination partly deglycosylated flagellin. After this treatment carbohydrates were still linked to protein as shown by a digoxigenin-hydrazide labelling. Therefore, in addition to linkages via serine, alkaline resistant linkages exist on the flagellin and some glycans may be linked to the protein core via the amide nitrogen of asparagine or via the hydroxyl group of tyrosine. Furthermore, according to an immunological analysis, glycans attached to flagellin via alkaline sensitive linkages may be different from those attached via alkaline resistant linkages.


Asunto(s)
Clostridium/metabolismo , Flagelina/metabolismo , Aminoácidos/química , Anticuerpos Monoclonales/inmunología , Conformación de Carbohidratos , Cromatografía Líquida de Alta Presión , Clostridium/crecimiento & desarrollo , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Flagelina/química , Glicopéptidos/química , Glicopéptidos/inmunología , Glicosilación , Pronasa/metabolismo
15.
Microbiol Immunol ; 42(2): 87-95, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9572040

RESUMEN

In order to count Clostridium tyrobutyricum spores in milk after membrane filtration, murine 21E7-B12 monoclonal antibody was produced. Elution of the monoclonal antibody from this antigen, the flagellar filament protein, by carbohydrate ligands was used to study the epitope structure. A competitive elution of an anti-dextran monoclonal antibody by carbohydrate ligands served as a control in order to validate the immunological tool applied to flagellin epitope study. The carbohydrate moiety of flagellin contained D-glucose and N-acetyl-glucosamine in a molar ration of 11:1 as determined by gas-liquid chromatography and 2 low-abundancy unidentified compounds. In ELISA, D-glucose and N-acetyl-glucosamine did not dissociate the antibody-flagellin complex contrary to maltose, maltotriose, maltotetraose and maltopentaose. The efficiency of elution increased from the dimer to the pentamer and became nil for maltohexaose and maltoheptaose. The fact that the hexamer and heptamer could not react with the 21E7-B12 monoclonal antibody could be explained by a drastic conformational change. The over-all stretched maltopentaose switch to a helical-shaped maltoheptaose which could not fit the 21E7-B12 monoclonal antibody antigen-combining site. Thus, flagellin epitope may contain alpha (1-->4) linked glucose residues plus either N-actyl-glucosamine or an unidentified compound that maintain it in an extended shape.


Asunto(s)
Anticuerpos Monoclonales , Clostridium/inmunología , Epítopos/química , Flagelina/química , Monosacáridos/química , Conformación de Carbohidratos , Clostridium/química , Clostridium/crecimiento & desarrollo , Epítopos/inmunología
16.
Microbiol Immunol ; 42(1): 23-31, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9525776

RESUMEN

The monoclonal antibody 21E7-B12 (IgG3) can be used in a direct method of Clostridium tyrobutyricum detection based on an immunoenzymatic assay. Immunoelectron microscopy demonstrated that the 21E7-B12 antibody recognized the surface-exposed epitopes on the flagellar filaments of C. tyrobutyricum. After flagellar extraction, the purified flagellin showed an apparent molecular mass of 46 kDa with an isoelectric point of 3.6. Sugar staining, mild periodate oxidation and beta-elimination experiments showed that the flagellin was glycosylated and that the 21E7-B12 epitope was located in the sugar moiety. Amino acid composition showed that the flagellar filament protein contained a high percentage of serine and threonine, while proline was absent. The first 23 residues of the N-terminal were determined and sequence homology with other flagellins was found.


Asunto(s)
Clostridium/química , Flagelina/química , Flagelina/inmunología , Secuencia de Aminoácidos , Anticuerpos Monoclonales/inmunología , Antígenos Bacterianos/química , Antígenos Bacterianos/inmunología , Clostridium/inmunología , Electroforesis en Gel de Poliacrilamida , Flagelos/ultraestructura , Glicosilación , Immunoblotting , Punto Isoeléctrico , Microscopía Inmunoelectrónica , Datos de Secuencia Molecular , Oxidación-Reducción , Ácido Peryódico , Homología de Secuencia de Aminoácido
18.
J Appl Microbiol ; 82(5): 619-24, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9172404

RESUMEN

The normal procedure for bacterial colony detection requires a nitrocellulose transfer step after membrane filtration and culture to prevent the development of a high background during the immunodetection. In this paper, we describe a modification of the basic protocol that omits the transfer step and reduces the risk of background. Previous observations indicated that interactions between milk components (principally cream) and membrane are responsible for the high non-specific staining observed. Experiments were performed to remove lipid components or to block the membrane binding sites before milk filtration. Samples of milks of different origin (collected at different times of the year) and different membranes were tested. The results obtained showed that removing lipids did not significantly improve the test but, on the contrary, led to an antigen diffusion. Incubation of the membrane in 0.1% (w/v) of Tween 20 in phosphate-buffered saline before milk filtration prevented non-specific binding, and allowed performance of the detection without any noticeable background.


Asunto(s)
Anticuerpos Antibacterianos/análisis , Anticuerpos Monoclonales/análisis , Clostridium/aislamiento & purificación , Membranas Artificiales , Leche/microbiología , Animales , Anticuerpos Antibacterianos/inmunología , Anticuerpos Monoclonales/inmunología , Antígenos Bacterianos/inmunología , Técnicas Bacteriológicas , Clostridium/inmunología , Colodión , Filtración , Técnicas para Inmunoenzimas , Esporas Bacterianas
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