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1.
NPJ Biofilms Microbiomes ; 9(1): 55, 2023 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-37573460

RESUMEN

The prevalence of antibiotic-resistant bacteria in Southeast Asia is a significant concern, yet there is limited research on the gut resistome and its correlation with lifestyle and environmental factors in the region. This study aimed to profile the gut resistome of 200 individuals in Malaysia using shotgun metagenomic sequencing and investigate its association with questionnaire data comprising demographic and lifestyle variables. A total of 1038 antibiotic resistance genes from 26 classes were detected with a mean carriage rate of 1.74 ± 1.18 gene copies per cell per person. Correlation analysis identified 14 environmental factors, including hygiene habits, health parameters, and intestinal colonization, that were significantly associated with the resistome (adjusted multivariate PERMANOVA, p < 0.05). Notably, individuals with positive yeast cultures exhibited a reduced copy number of 15 antibiotic resistance genes. Network analysis highlighted Escherichia coli as a major resistome network hub, with a positive correlation to 36 antibiotic-resistance genes. Our findings suggest that E. coli may play a pivotal role in shaping the resistome dynamics in Segamat, Malaysia, and its abundance is strongly associated with the community's health and lifestyle habits. Furthermore, the presence of yeast appears to be associated with the suppression of antibiotic-resistance genes.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Humanos , Malasia , Escherichia coli/genética , Saccharomyces cerevisiae , Microbioma Gastrointestinal/genética , Heces/microbiología , Antibacterianos/farmacología , Demografía
2.
Lab Chip ; 14(18): 3510-8, 2014 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-25012393

RESUMEN

Microfluidic bioreactors are expected to impact cell therapy and biopharmaceutical production due to their ability to control cellular microenvironments. This work presents a novel approach for continuous cell culture in a microfluidic system. Microcarriers (i.e., microbeads) are used as growth support for anchorage-dependent mammalian cells. This approach eases the manipulation of cells within the system and enables harmless extraction of cells. Moreover, the microbioreactor uses a perfusion function based on the biocompatible integration of a porous membrane to continuously feed the cells. The perfusion rate is optimized through simulations to provide a stable biochemical environment. Thermal management is also addressed to ensure a homogeneous bioreactor temperature. Eventually, incubator-free cell cultures of Drosophila S2 and PC3 cells are achieved over the course of a week using this bioreactor. In future applications, a more efficient alternative to harvesting cells from microcarriers is also anticipated as suggested by our positive results from the microcarrier digestion experiments.


Asunto(s)
Reactores Biológicos , Técnicas de Cultivo de Célula , Técnicas Analíticas Microfluídicas , Animales , Técnicas de Cultivo de Célula/instrumentación , Técnicas de Cultivo de Célula/métodos , Línea Celular Tumoral , Drosophila melanogaster , Humanos , Técnicas Analíticas Microfluídicas/instrumentación , Técnicas Analíticas Microfluídicas/métodos
3.
J Evol Biol ; 23(6): 1195-205, 2010 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-20406349

RESUMEN

Sign and magnitude of local adaptation in host-parasite systems may vary with ecological, epidemiological or genetic parameters. To investigate the role of host genetic background, we established long-term experimental populations of different genotypes of the protozoan Paramecium caudatum, infected with the bacterial parasite Holospora undulata. We observed the evolution of an overall pattern of parasite local maladaptation for infectivity, indicating a general coevolutionary disadvantage of this parasite. Maladaptation extended to host populations with the same genetic background, similar to extending from the local to a higher regional level in natural populations. Patterns for virulence were qualitatively similar, but with less statistical support. A nonsignificant correlation with levels of (mal)adaptation for infectivity suggests independent evolution of these traits. Our results indicate similar (co)evolutionary trajectories in populations with different genetic backgrounds. Nonetheless, the correlated clines of genetic distance and parasite performance illustrate how genetic background can shape spatial gradients of local adaptation.


Asunto(s)
Adaptación Fisiológica , Evolución Biológica , Holosporaceae/fisiología , Interacciones Huésped-Patógeno , Paramecium caudatum/microbiología , Animales , Holosporaceae/patogenicidad , Paramecium caudatum/fisiología , Virulencia
4.
Mol Ecol ; 9(10): 1591-7, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11050554

RESUMEN

Microsatellite variation from eight loci was studied in five populations of Drosophila teissieri, a fruit-fly found only in the rain forests of sub-Saharan Africa. Five noncontiguous rain forest sites (from Tanzania, Gabon and Ivory Coast) were sampled to measure the effects of historical forest fragmentation on population structure in an obligatory forest-dwelling species. The Ivory Coast and Gabon populations showed a wider range of alleles, different modal alleles and had a higher genetic diversity than the three East African populations. As could be expected, genetic differentiation (FST) was significantly correlated with physical distance, but the westernmost population (Ivory Coast) showed values that were intermediate between the central (Gabon) and Eastern (Tanzania) populations. A migration-drift equilibrium in a stable continuum of populations did not appear adequate to describe the observed distribution. It seems probable that the species has undergone abrupt changes involving isolation, merging and migration of populations, as a consequence of repeated waves of forest fragmentation and coalescence.


Asunto(s)
Drosophila/genética , Genética de Población , África , Animales , Femenino , Variación Genética , Masculino , Repeticiones de Microsatélite , Modelos Genéticos
5.
J Biol Chem ; 275(34): 26002-10, 2000 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-10846180

RESUMEN

The red cell ICAM-4/LW blood group glycoprotein, which belongs to the family of intercellular adhesion molecules (ICAMs), has been reported to interact with CD11a/CD18 (LFA-1) and CD11b/CD18 (Mac-1) beta(2) integrins. To better define the basis of the ICAM-4/beta(2) integrin interaction, we have generated wild-type, domain-deleted and mutated recombinant chimeric ICAM-4-Fc proteins and analyzed their interaction in a cellular adhesion assay with LFA-1 and Mac-1 L-cell stable transfectants. We found that monoclonal antibodies against CD11a, CD11b, CD18, or LW(ab) block adhesion of transfectant L-cells to immobilized ICAM-4-Fc protein and that the ICAM-4/beta(2) integrin interaction was highly sensitive to the presence of the divalent cations Ca(2+) and Mg(2+). Deletion of individual Ig-domains D1 or D2 of the extracellular part of ICAM-4 showed that LFA-1 binds to the first Ig-like domain, whereas the Mac-1 binding site encompassed both the first and the second Ig-like domains. Based on the crystal structure of ICAM-2, we propose a model for the Ig-like domains D1 and D2 of ICAM-4. Accordingly, by site-directed mutagenesis of 22 amino acid positions spread out on all faces of the ICAM-4 molecule, we identified four exposed residues, Leu(80), Trp(93), and Arg(97) on the CFG face and Trp(77) on the E-F loop of domain D1 that may contact LFA-1 as part of the binding site. However, the single and double mutants R52E and T91Q on the CFG face of domain D1, which correspond to the key residues Glu(34) and Gln(73) for ICAM-1 binding to LFA-1, had no effect on LFA-1 binding. In contrast, all mutants on the CFG face of domain D1 and residues Glu(151) and Thr(154) in the C'-E loop of the domain D2 seem to play a dominant role in Mac-1 binding. These data suggest that the binding site for LFA-1 on ICAM-4 overlaps but is distinct from the Mac-1 binding site.


Asunto(s)
Moléculas de Adhesión Celular/metabolismo , Antígeno-1 Asociado a Función de Linfocito/metabolismo , Antígeno de Macrófago-1/metabolismo , Secuencia de Aminoácidos , Animales , Sitios de Unión , Antígenos CD18/metabolismo , Células COS , Calcio/metabolismo , Moléculas de Adhesión Celular/genética , Cristalografía por Rayos X , Humanos , Magnesio/metabolismo , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Conformación Proteica , Relación Estructura-Actividad
6.
Blood ; 95(5): 1819-26, 2000 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-10688843

RESUMEN

CD99, the product of the MIC2 gene, exhibits an erythroid-specific quantitative polymorphism coregulated with the polymorphism of the XG blood group gene. As a preliminary study of this phenomenon, human XG and CD99 recombinant proteins were expressed in murine RAG cells and analyzed by flow cytometry. Both proteins were expressed independently and at a similar level in single and double transfectants. Immunoprecipitation and Western blot analysis, using the murine monoclonal antibodies NBL-1 and 12E7, revealed species of 26 kd (XG) and 32 kd (CD99), respectively. A putative 28-kd intracellular precursor of CD99 was also detected, as was a 26-kd species after neuraminidase treatment of CD99-expressing cells. No evidence of association or complex formation between XG and CD99 proteins could be proven, either on transfected RAG cells or on human erythrocytes. These results were confirmed using somatic hybrids between single transfectants. These findings suggest that the phenotypic relationship between XG and CD99 is mostly regulated at the transcriptional level, but they do not formally exclude some posttranscriptional effect. Studies on the tissue specificity of XG expression showed that surface expression of the XG protein could not be restored in somatic hybrids between B-lymphoblastoid cell lines from Xg(a+) persons and fibroblasts (RAG) or erythroid (MEL) cells. RT-PCR analysis of the transcripts revealed the existence of an XG mRNA in each cell line, suggesting that the tissue-specific regulation of cell surface XG expression occurs either at a quantitative transcriptional level or is a posttranscriptional event. By Northern blot analysis, XG transcripts were detected in erythroid tissues and several nonerythroid tissues. (Blood. 2000;95:1819-1826)


Asunto(s)
Antígenos CD/biosíntesis , Moléculas de Adhesión Celular/biosíntesis , Células Eucariotas/metabolismo , Regulación de la Expresión Génica , Antígeno 12E7 , Adenocarcinoma/patología , Animales , Antígenos CD/genética , Antígenos de Grupos Sanguíneos , Moléculas de Adhesión Celular/genética , Eritrocitos/metabolismo , Fibroblastos/metabolismo , Humanos , Células Híbridas/metabolismo , Ratones , Peso Molecular , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Especificidad de Órganos , Precursores de Proteínas/biosíntesis , ARN Mensajero/biosíntesis , Proteínas Recombinantes de Fusión/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas
7.
Hist Sci Med ; 34(3): 289-94, 2000.
Artículo en Francés | MEDLINE | ID: mdl-11640523

RESUMEN

The Constantinople Imperial Bacteriology Institute (CIBI) allowed the development of a common medical effort between France and Turkey at a time when the main European powers were competing to have an influence on the Ottoman Empire. In 1887, Turkey sent Zoreos Pacha, a medical doctor, to Paris to learn anti-rabies immunization techniques, and he started a rabies control institute after his coming back. In 1893, a cholera epidemic in Constantinople was vanquished by A. Chantemesse, sent by Pasteur, and France was allowed to start another microbiologic Institute. The first director of this Constantinople Imperial Bacteriology Institute was Maurice Nicolle. A brillant man, but suffering from a lack of diplomacy; he encountered numerous difficulties and regularly threatened to turn in his resignation. His successor, Paul Remlinger, arrived in 1900. His main research topic was rabies, and he became later a world-class expert on the subject. His position was taken over in 1911 by Paul-Louis Simond, unjustly forgotten nowadays despite his major discovery in 1898 showing that the plague was transmitted by ratfleas. The next director was a veterinary doctor, P. Forgeot, but his tenure was cut short by World War I, and he was the last French director of the CIBI. Since that time, Turkey has felt some gratitude towards France for its medical efforts. It organized in 1957 in Istambul a very congenial celebration for the 70th anniversary of the Rabies Control Institute, which numerous Pasteur Institute alumni attended. There is a clear contrast between the CIBI, the target of many intrigues and hostile maneuvers, and the North African Pasteur Institutes, which were making crucial discoveries during the same period. This contrast was mostly due to the absolute power of the Sultan, who would arbitrarily oppose some directors decisions, whereas the French government allowed the balanced growth of the Pasteur Institutes in territories under his control.


Asunto(s)
Academias e Institutos/historia , Bacteriología/historia , Cooperación Internacional/historia , Francia , Historia del Siglo XIX , Historia del Siglo XX , Política , Turquía
9.
Exp Toxicol Pathol ; 49(1-2): 91-5, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9085082

RESUMEN

Oxygen free radicals (OFR) are highly cytotoxic when produced in the myocardium under certain pathological conditions. In isolated rat hearts perfused retrogradely, OFR were generated by electrolysis of the Krebs-Henseleit buffer (two platinum electrodes, DC current, 10 mA, 1 min). In order to find evidence that OFR are produced, we used nitro blue tetrazolium (NBT) a soluble compound which yields a dark blue formazan pigment in the presence of reducing agents. Hearts were subdivided into: control, electrolysed, NBT (3.3 mg/ml) perfusion during electrolysis in the presence or absence of scavengers. The xanthine-xanthine oxidase (XXO) system known to produce superoxide radical was used as a reference. Specimens were fixed with formaldehyde and stained with eosine or Kernechtrot in preparation for light microscopical examination. Several areas of acute necrosis expressed by hyalinisation and loss of striation were observed in electrolysed hearts which present a pattern of wavy disrupted myofibers and an increase in interstitial spaces. A very faint deposition of formazan was observed in some rare areas of NBT perfused heart. Only the electrolysed group perfused with NBT and the one perfused with XXO plus NBT presented an extensive formazan deposition, mostly in the areas of fibre necrosis. Formazan was barely detectable when superoxide dismutase plus catalase were perfused in the XXO system, while it was still apparent when perfused in electrolysed hearts. These results support the hypothesis that electrolysis can be used to generate different species of OFR and to evaluate the protective action of scavenger and antioxidants against OFR-induced myocardial damage.


Asunto(s)
Electrólisis , Indicadores y Reactivos/metabolismo , Miocardio/metabolismo , Nitroazul de Tetrazolio/metabolismo , Superóxidos/metabolismo , Animales , Catalasa/administración & dosificación , Corazón/efectos de los fármacos , Corazón/fisiología , Técnicas In Vitro , Masculino , Miocardio/patología , Perfusión , Ratas , Ratas Wistar , Superóxido Dismutasa/administración & dosificación , Xantina Oxidasa/farmacología
10.
Dev Biol Stand ; 86: 225-41, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8785953

RESUMEN

Passive haemagglutination tests have been developed by covalent coupling purified antigens to turkey red blood cells. Circulating antibodies can be assessed in 20 minutes using one drop of blood. False positive reactions are avoided by using highly purified antigens; sensitized erythrocytes are stable in the absence of freeze-drying and blood samples can be preserved on paper discs. This method, applied to the determination of circulating tetanus (T) and diphtheria (D) antibodies and titres compared to other in vivo or in vitro methods, gave good correlation. The titration of circulating antibodies can be applied in emergency care units and field trials to establish whether the individuals are adequately protected. Results of surveys by several health care centres have shown that tetanus immune coverage was insufficient in France. The decrease of both T and D immune coverage with age has been established. The antibody response of pregnant women, vaccinated with two different adsorbed T toxoids exhibiting a low and a high titre as expressed in international immunizing units (I.I.U.), was studied. No significant difference in circulating antibody titres was obtained after the first injection of either vaccine, but titres after second injection were much higher for the vaccine having a low value expressed in I.I.U. The activity of commercial and reference T vaccines can be evaluated in mice after immunization and titration of the antitoxin levels. This simple method is much easier than the official evolution of immunodeficiency in certain diseases. The passive haemagglutination test has also been used to measure anti-HBs and anti-gp 160 antibodies.


Asunto(s)
Alternativas a las Pruebas en Animales/métodos , Antígenos , Eritrocitos/inmunología , Pruebas de Hemaglutinación/métodos , Animales , Anticuerpos Antibacterianos/sangre , Antígenos/aislamiento & purificación , Clostridium tetani/inmunología , Corynebacterium diphtheriae/inmunología , Difteria/inmunología , Difteria/prevención & control , Toxoide Diftérico/análisis , Toxoide Diftérico/inmunología , Toxoide Diftérico/farmacología , Ensayo de Inmunoadsorción Enzimática , Estudios de Evaluación como Asunto , Femenino , Francia , Tolerancia Inmunológica , Ratones , Pruebas de Neutralización , Embarazo , Tétanos/inmunología , Tétanos/prevención & control , Toxoide Tetánico/análisis , Toxoide Tetánico/inmunología , Toxoide Tetánico/farmacología , Pavos
11.
Artículo en Inglés | MEDLINE | ID: mdl-8803511

RESUMEN

The relationship between exhaustion time (tlim) and distance Dlim for running exercises at constant velocity until exhaustion can be described by a linear relationship (Dlim = a + b tlim) whose slope corresponds to a critical velocity. Seven runners participated to the study which compared the critical velocity of continuous versus intermittent running exercises. The critical velocity for continuous running (Vcritc) was calculated from the results (tlimc and Dlimc) of running exercises performed at 95 and 105% of the final velocity of the Montreal Track Test (vMTT). The intermittent running consisted of repetitions of running exercises performed at 95 and 105% vMTT during a time equal to half the value of the corresponding tlimc. The subjects recovered during a time equal to running time while jogging at a slow pace. The critical velocity for intermittent running (Vcriti) was calculated from the cumulated running distance (Dlimi) and cumulated running time (tlimi) corresponding to 95 and 105% vMTT. Vcriti was equal to Vcritc (4.56 +/- 0.444 m.s-1 vs 4.60 +/- 0.416 m.s-1). Nevertheless, in some subjects, the repetition numbers were very different for the intermittent running exercises at 95 and 105% vMTT. This paradoxical result could be explained by the fact that the value of Vcrit should be theoretically little sensitive to a large error in the value of tlim corresponding to a velocity slightly higher than critical velocity, for intermittent exercises as well as continuous exercises.


Asunto(s)
Ejercicio Físico/fisiología , Aptitud Física/fisiología , Carrera , Adulto , Umbral Anaerobio/fisiología , Humanos , Masculino , Resistencia Física/fisiología
12.
Arch Physiol Biochem ; 104(3): 330-6, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8793025

RESUMEN

The velocity of the last stage of the Montreal Track Test (MTT) has been measured in fifteen well trained runners. This velocity (vMTT) was assumed to be close to maximal aerobic running speed. In three different sessions, the subjects ran up to exhaustion at velocities corresponding to 95, 100 and 105% vMTT. The exhaustion time at 100 % vMTT (tlim100) was assumed to be an estimation of the exhaustion time corresponding to maximal aerobic speed. The relationship between exhaustion time (tlim) and distance (Dlim) in the case of running exercises at constant velocity until exhaustion can be described by a linear relationship (Dlim = D + b*tlim). The slope of the relation corresponds to a velocity (vcrit) which can be sustained for a long time. The values of vcrit were calculated from the results of running exercises performed at 95, 100 and 105% of vMTT. The present study showed that tlim at 100% vMTT (tlim100) was negatively correlated with vMTT and vcrit but that D and ratio vcrit/vMTT were independent of vMTT. A theoretical study based on models previously proposed for oxygen kinetics during supramaximal exercises (exponential model and Margaria's model) demonstrates that this negative relationship between vMTT and tlim100 can be explained by the kinetics of the accumulation of oxygen deficit (O2 def). tlim100 should also depend on VO2max, maximal oxygen deficit (Max O2 def) and the relative importance of anaerobic energy when a VO2 plateau is reached. Moreover, the value of tlim100 largely depends on the accuracy of the assessment of vMTT. Consequently, the exhaustion times corresponding to the different estimations of maximal aerobic speed on a track or a treadmill cannot be considered as valid indices of aerobic endurance.


Asunto(s)
Resistencia Física/fisiología , Adulto , Análisis de Varianza , Humanos , Ácido Láctico/sangre , Consumo de Oxígeno , Carrera/fisiología , Factores de Tiempo
13.
J Biol Chem ; 270(26): 15607-10, 1995 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-7797558

RESUMEN

The gene encoding the urea transporter of human erythrocytes (HUT11 clone) has been cloned recently (Olives, B., Neau, P., Bailly, P., Hediger, M. A., Rousselet, G., Cartron, J. P., and Ripoche, P. (1994) J. Biol. Chem. 269, 31649-31652). Now, this gene has been assigned to chromosome 18q12-q21 by in situ hybridization, as also found for the Kidd (Jk) blood group locus. In coupled transcription-translation assays, the HUT11 cDNA directed the synthesis of a 36-kDa protein which was immunoprecipitated by a human anti-Jk3 antibody produced by immunized Jk(a-b-) donors whose red cells lack Kidd antigens. The anti-Jk3 antibody also immunoprecipitated a protein material of 46-60 kDa from all red cell membranes, except those from Jk(a-b-) cells. After N-glycanase digestion the 46-60-kDa component was reduced to 36 kDa. A rabbit antibody raised against the predicted NH2-terminal amino-acids of the HUT11 protein reacted on immunoblots with a 46-60-kDa component present in all human erythrocytes except those from Jk(a-b-) individuals. Jk(a-b-) red cells lack the Kidd/urea transport protein and have a selective defect of the urea transport capacity, but a normal water permeability and aquaporin-associated Colton blood group antigens. These findings indicate that the erythrocyte urea transporter is encoded by the Kidd locus and may have implications for the biology of urea transporters and their tissue-specific regulation.


Asunto(s)
Proteínas Portadoras/fisiología , Eritrocitos/metabolismo , Sistema del Grupo Sanguíneo de Kidd/fisiología , Urea/metabolismo , Animales , Transporte Biológico , Proteínas Portadoras/genética , Mapeo Cromosómico , Humanos , Sistema del Grupo Sanguíneo de Kidd/genética , Peso Molecular , Permeabilidad , Conejos
14.
Psyche (Stuttg) ; 48(12): 1123-53, 1994 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-7846291

RESUMEN

This article reports on a project in which mothers living in conditions describable as suproletarian are given psychotherapeutic treatment alongside practical care. The special feature of this system of comprehensive care for mothers from so-called "hard-to-reach-families" is that it begins during pregnancy, is instituted via the agency of midwives and that the therapeutic sessions are designed on a long-term basis and take place in the mothers' own homes. In two detailed case reports the authors describe their methods and define the objectives pursued by this project - the stabilization of the mothers in their family life situation and the prevention, from birth, of disturbances and disabilities otherwise to be anticipated in the children themselves.


Asunto(s)
Maltrato a los Niños/prevención & control , Trastornos de la Conducta Infantil/prevención & control , Grupos Minoritarios/psicología , Relaciones Madre-Hijo , Pobreza/psicología , Terapia Psicoanalítica/métodos , Carencia Psicosocial , Adulto , Niño , Maltrato a los Niños/psicología , Trastornos de la Conducta Infantil/psicología , Hijo de Padres Discapacitados/psicología , Preescolar , Terapia Combinada , Terapia Familiar/métodos , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Grupo de Atención al Paciente , Determinación de la Personalidad , Embarazo
16.
Blood ; 82(2): 669-76, 1993 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-8329720

RESUMEN

Rabbit polyclonal antibodies were raised against synthetic peptides corresponding to hydrophilic regions of the human Rhesus (Rh) IX cDNA-encoded polypeptide predicted to be extracellularly or intracellularly exposed in the topologic model of the Rh blood group protein. Four antibodies encompassing residues 33-45 (MPC1), 224-233 (MPC4), 390-404 (MPC6), and 408-416 (MPC8) were characterized and compared with a polyclonal anti-Rh protein obtained by immunization with purified Rh proteins. All antibodies had specificity for authentic Rh polypeptides and reacted on Western blot with Rh proteins immunoprecipitated with human monoclonal anti-RhD, -c, and -E. MPC1, but not the other antibodies, agglutinated all human erythrocytes except Rhnull and Rhmod cells, which either lack totally or are severely deficient in Rh proteins, respectively. Immunoblotting analysis with membrane proteins from common and rare variants showed that MPC1 and MPC8 reacted in Western blot with 32-Kd Rh polypeptides from all common red blood cells except those from Rhnull and Rhmod, indicating that peptide regions 33-45 and 408-416 may be common to several if not all Rh proteins, whatever the Rh blood group specificity. MPC4 reacted only with membrane preparations from cells carrying the E antigen, whereas MPC6 recognized preferentially the Rh proteins from E and Ee preparations, suggesting that the protein encoded by the RhIXb cDNA carries the E and/or e antigen(s). Immunoadsorption experiments using inside-out or right-side-out sealed vesicules from DccEE red blood cells as competing antigen showed that the MPC6 and MPC8 antibodies bound only to the cytoplasmic side of the erythrocyte membrane, thus providing evidence for the intracellular orientation of the C-terminal 27 residues of the Rh polypeptides. Attempts to transiently or stably express the Rh polypeptides. Attempts to transiently or stably express the Rh cDNA in eukaryotic cells were largely unsuccessful, suggesting that Rh antigen expression at the cell surface requires correct transport and/or folding of the Rh proteins, possibly as a complex with one-membrane proteins of the Rh cluster that are lacking in Rhnull cells.


Asunto(s)
Fragmentos de Péptidos/inmunología , Sistema del Grupo Sanguíneo Rh-Hr/inmunología , Animales , Anticuerpos/inmunología , Especificidad de Anticuerpos , Western Blotting , Ensayo de Inmunoadsorción Enzimática , Membrana Eritrocítica/química , Variación Genética , Humanos , Immunoblotting , Proteínas de la Membrana/sangre , Proteínas de la Membrana/química , Proteínas de la Membrana/inmunología , Ratones , Sistema del Grupo Sanguíneo Rh-Hr/genética
17.
Am J Hematol ; 40(4): 306-12, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1503086

RESUMEN

Another example of rare red cells that failed to react with all anti-Rh and anti-LW antibodies was discovered in a Spanish woman suffering from a severe hemolytic anemia typical of the Rhnull syndrome. Family study and Rh blood typings demonstrated clearly that the proposita was homozygous for a silent Rh gene complex (Rhnull of the amorph type) that she inherited from her parents who are first cousins. Western blot analysis carried out with glycosylation-independent antibodies directed against the Rh polypeptide and the LW glycoprotein, respectively, confirmed that these protein components were absent from the red cells of the proposita. In addition, the patient was typed U-positive, again in agreement with the presence on her red cells of 45-75 kDa glycoproteins detected with the murine monoclonal antibody 2D10.


Asunto(s)
Genes/genética , Sistema del Grupo Sanguíneo Rh-Hr/genética , Adulto , Anemia Hemolítica/sangre , Anemia Hemolítica/epidemiología , Anemia Hemolítica/inmunología , Anticuerpos Monoclonales/análisis , Anticuerpos Monoclonales/inmunología , Western Blotting , Femenino , Genes/inmunología , Homocigoto , Humanos , Masculino , Linaje , Fenotipo , Sistema del Grupo Sanguíneo Rh-Hr/inmunología , España
18.
Biologicals ; 20(1): 35-43, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1610557

RESUMEN

The activity of several Tetanus Toxoids, Adsorbed, (commercial vaccines and references) were tested in mice in comparison with a standard, by a simple method, easier than the official challenge test (WHO and European Pharmacopoeia): the Tetanus Antitoxin level was titrated by agglutination of sensitized turkey red blood cells after immunization by the toxoids. Immuno-stimulation by the Pertussis component in associated vaccines was studied and the results with the conventional and the acellular Pertussis preparations were prepared. The method was also found to be suitable for Tetanus Toxoids, Non-Adsorbed, when a booster effect was used, except for the adjuvant-free polymerized antigen (POLAN) which did not require a booster, since it gave almost as good results as conventional adsorbed tetanus vaccines.


Asunto(s)
Toxoide Tetánico/análisis , Animales , Bioensayo/métodos , Estudios de Evaluación como Asunto , Femenino , Inmunización , Ratones , Vacuna contra la Tos Ferina/administración & dosificación , Estándares de Referencia , Antitoxina Tetánica/sangre , Toxoide Tetánico/administración & dosificación , Toxoide Tetánico/normas
19.
Biologicals ; 20(1): 67-71, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1610560

RESUMEN

Working reference preparations of anti-pertussis sera from various National Control Laboratories were assayed for anti-PT antibodies by standardized ELISA and toxin neutralization (Nt) test. Both the ELISA and Nt tests gave highly reproducible results for various preparations when these preparations were assayed repeatedly on different days. Various working reference preparations were assigned units against the proposed International standard for anti-pertussis serum (JNIH-10) assuming its unitage of 250. Assigning unitage to various preparations would help in comparing results of ELISA and Nt tests for anti-PT antibodies reported in various studies.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Bordetella pertussis/inmunología , Toxina del Pertussis , Factores de Virulencia de Bordetella/inmunología , Ensayo de Inmunoadsorción Enzimática , Estudios de Evaluación como Asunto , Humanos , Sistema Internacional de Unidades/normas , Pruebas de Neutralización , Estándares de Referencia
20.
Vaccine ; 9(11): 843-50, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1759508

RESUMEN

The antibody response to pertussis toxin (PT) and agglutinogens of children vaccinated in Japan, France and Senegal with either whole cell or component pertussis vaccine was determined at various times after immunization. Agglutinin titres were almost similar in sera of Japanese children vaccinated with either whole cell or component pertussis vaccine whereas anti-PT antibody levels were found to be higher after vaccination with whole cell vaccine than with component vaccine. The geometric mean (GM) agglutinin titres in sera of Japanese children amounted to 45.0 and 45.7, respectively, and neutralization GM titres to 71.6 and 22.6, respectively, following vaccination with the whole cell and component pertussis vaccines. Sera of French children receiving three doses of whole cell vaccine exhibited a GM agglutinin titre of 17.8, whereas only 16% of sera contained neutralizing antibodies against PT. Following the booster dose the GM agglutinin titre rose to 213.5 and 68% of the sera contained neutralizing antibodies to PT (GM titre 48.0). Sera of Senegalese children receiving three doses of whole cell vaccine exhibited a GM agglutinin titre of 18.7, whereas anti-PT neutralizing antibodies were hardly detected. Agglutinins and anti-PT antibody in sera of French and Senegalese children turned out to be lower than were found 25 years ago in sera of children immunized with the French whole cell pertussis vaccine.


Asunto(s)
Aglutininas/sangre , Anticuerpos Antibacterianos/sangre , Bordetella pertussis/inmunología , Toxoide Diftérico/inmunología , Vacuna contra Difteria, Tétanos y Tos Ferina/inmunología , Toxina del Pertussis , Vacuna contra la Tos Ferina/inmunología , Vacuna Antipolio de Virus Inactivados/inmunología , Toxoide Tetánico/inmunología , Factores de Virulencia de Bordetella/inmunología , Tos Ferina/prevención & control , Adolescente , Niño , Preescolar , Combinación de Medicamentos , Francia/epidemiología , Humanos , Incidencia , Lactante , Japón/epidemiología , Senegal/epidemiología , Vacunas Combinadas , Tos Ferina/epidemiología
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