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1.
Int J Cancer ; 78(5): 600-5, 1998 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-9808529

RESUMEN

Loss of heterozygosity (LOH) studies reported thus far suggest that tumor suppressor loci on chromosome 5q are important in esophageal cancer (EC) while little is known about the involvement of chromosome 5p. To investigate the potential existence of tumor suppressor gene(s) on chromosome 5 contributing to the development of EC, we performed LOH studies using a total of 24 polymorphic markers spanning the entire chromosome 5. Seventy primary esophageal cancers were microdissected and allelic deletions were detected by polymerase chain reaction (PCR)-single strand conformation polymorphism or by microsatellite analysis. LOH was observed in at least 1 of the loci in 47 of 70 (67%) esophageal tumors. Initially, 40 tumors [24 squamous cell carcinomas (SCC) and 16 adenocarcinomas (ADC)], each with matched histologically normal esophageal mucosa, were analyzed at 15 marker loci on 5p and 5q. A novel locus, D5S667 on 5p15.2, exhibited the highest frequency of LOH (44%) in these tumors along with another previously reported region of frequent deletion, irf-1 (5q31.1). In a series of 30 additional EC tumors (11 SCC and 19 ADC), a detailed LOH analysis of chromosome 5p15.2 region was conducted using 10 additional polymorphic markers, which mapped the frequently deleted region within 1 cM. Overall, LOH at the D5S667 locus was observed more frequently in SCC than in ADC (62% vs. 23%, p = 0.01). This significant rate of LOH of a distinct region of chromosome 5p implicates the existence of a putative tumor suppressor gene locus involved in EC.


Asunto(s)
Cromosomas Humanos Par 5 , Neoplasias Esofágicas/genética , Pérdida de Heterocigocidad , Adenocarcinoma/genética , Carcinoma de Células Escamosas/genética , Mapeo Cromosómico , Humanos
2.
Vaccine ; 16(4): 388-93, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9607060

RESUMEN

The efficacy of chicken egg yolk homotypic antibodies specific for outer membrane proteins (OMP), lipopolysaccharide (LPS) or flagella (Fla) in controlling experimental salmonellosis in mice was investigated. Mice challenged orally with 2 x 10(9) c.f.u. of Salmonella enteritidis or 2 x 10(7) c.f.u. of S. typhimurium were orally treated with 0.2 ml anti-OMP, -LPS or -Fla yolk antibody three times a day for three consecutive days. In mice challenged with S. enteritidis, antibody treatment resulted in a survival rate of 80%, 47% and 60% using OMP, LPS or Fla specific antibodies respectively, in contrast to only 20% in control mice. In the S. typhimurium trial, survival rate was 40%, 30% and 20% using OMP, LPS or Fla specific antibodies respectively in contrast to 0% in control mice. In vitro adhesion of S. enteritidis and S. typhimurium to HeLa cells was significantly reduced by anti-OMP, -LPS, and -Fla homotypic antibodies. Results suggest that egg yolk antibodies specific for Salmonella OMP, LPS, and Fla may protect mice from experimental salmonellosis when passively administered orally. Of these antibodies, anti-OMP exhibited the highest level of protection in vivo and in vitro.


Asunto(s)
Anticuerpos Antibacterianos/uso terapéutico , Vacunas Bacterianas/uso terapéutico , Inmunización Pasiva , Infecciones por Salmonella/prevención & control , Salmonella enteritidis/inmunología , Salmonella typhimurium/inmunología , Animales , Anticuerpos Antibacterianos/inmunología , Femenino , Células HeLa , Humanos , Ratones , Ratones Endogámicos BALB C
3.
Am J Vet Res ; 59(4): 416-20, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9563623

RESUMEN

OBJECTIVE: To protect neonatal calves against fatal salmonellosis within the first 2 weeks after birth, using chicken egg yolk antibodies specific against Salmonella typhimurium or S dublin. ANIMALS: 38 neonatal Holstein calves from Salmonella-free farms. PROCEDURE: After removal of the lipid components with hydroxypropylmethylcellulose phthalate, egg yolk antibodies were spray dried. At 4 days of age, calves were challenge exposed by oral inoculation with 10(11) virulent S typhimurium (experiment 1) or S dublin (experiment 2). Starting from the challenge-exposure day, egg yolk antibody preparations were administered orally 3 times a day for 7 to 10 days. RESULTS: In passive immunization trials, the orally administered antibodies conferred dose-dependent protection against infection with each of the homologous strains of Salmonella. Within 7 to 10 days after challenge exposure, all control calves died, whereas low-titer antibody-treated calves had 60 to 100% mortality. Only fever and diarrhea, but no deaths (P < 0.01), were observed in calves given the highest titer of antibody. CONCLUSIONS AND CLINICAL RELEVANCE: Compared with that in control calves, survival was significantly higher among calves given antibodies with titers of 500 (P < 0.05) and 1,000 (P < 0.01) homotypic for S typhimurium and with titer of 5,000 (P < 0.01) for S dublin. Egg yolk antibodies specific for whole cell S typhimurium or S dublin are protective against fatal salmonellosis when given in sufficiently high concentration, and may be clinically useful during a salmonellosis outbreak.


Asunto(s)
Anticuerpos Antibacterianos/administración & dosificación , Yema de Huevo/inmunología , Inmunización Pasiva/veterinaria , Salmonelosis Animal/prevención & control , Salmonella typhimurium , Salmonella/inmunología , Administración Oral , Animales , Animales Recién Nacidos , Bovinos , Pollos , Inmunización Pasiva/métodos , Salmonelosis Animal/mortalidad , Salmonella typhimurium/inmunología
4.
J Vet Med Sci ; 58(4): 365-7, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8741272

RESUMEN

Two types of chicken egg yolk antibody samples for oral passage trials in calves were prepared: (1) hydroxypropyl methylcellulose phthalate (HPMCP) antibody powder (HAP)--a powder produced by spray-drying a supernatant obtained after precipitation of lipids from egg yolk with HPMCP and (2) control antibody power (CAP)--a powder produced from an antibody solution with HPMCP. Antibody activity and pattern of distribution of both antibody preparations in the gastrointestinal tract of calves were compared by enzyme-linked immunosorbent assay. At 2 hr post administration, anti-K99 fimbrial antibodies from both the CAP and the HAP were detected in the abomasum of calves with titers of 1:128 and 1:256, respectively. However, at 4 hr, anti-K99 fimbrial titers of the CAP and the HAP were reduced to 1:2 and 1:64, respectively, due to digestion in the abomasum. These results indicated that the egg yolk antibody powder with HPMCP was more resistant against gastric juice in the stomach, thereby, ensuring a transfer of functional antibodies to the small intestine of calves after oral administration.


Asunto(s)
Anticuerpos/metabolismo , Yema de Huevo/inmunología , Tránsito Gastrointestinal , Metilcelulosa/análogos & derivados , Abomaso , Administración Oral , Animales , Animales Recién Nacidos , Anticuerpos/administración & dosificación , Anticuerpos Antibacterianos/metabolismo , Bovinos , Ciego , Pollos , Colon , Calostro , Ensayo de Inmunoadsorción Enzimática , Escherichia coli/inmunología , Fimbrias Bacterianas/inmunología , Intestino Delgado , Recto
5.
J Med Microbiol ; 41(1): 29-35, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7911840

RESUMEN

Chickens were immunised with a preparation of purified 14-kDa fimbriae of Salmonella serotype Enteritidis (SEF 14) to raise egg-yolk antibodies for protection trials in mice against subsequent challenge-exposure with the homologous strain of Enteritidis. A pronounced specificity of egg-yolk antibodies against the 14-kDa fimbrial antigen was demonstrated by Western blotting analysis. Passive antibody protection was evaluated in a mouse model of experimental salmonellosis: 79 mice (CD 1 strain) were challenged orally with 2 x 10(10) cfu of Enteritidis. Test mice treated with SEF-14 antibodies (titre = 128) had a survival rate of 77.8% compared to 32% survival in control mice fed normal egg-yolk antibodies (titre < 10) (p < 0.01). In-vitro adhesion of Enteritidis to mouse intestinal epithelial cells was reduced by anti-fimbrial antibodies. An indirect immunofluorescence method demonstrated the localisation of Enteritidis along the villous margins of the small intestine of control mice, whereas in test mice adherent bacteria were not detected. Results suggest that 14-kDa fimbriae may influence, enhance or contribute to the overall adhesive properties of Enteritidis and that egg-yolk antibodies directed against these fimbriae may have played a substantial role in protection, possibly by minimising bacterial colonisation and invasion during the early stages of infection.


Asunto(s)
Anticuerpos Antibacterianos/uso terapéutico , Fimbrias Bacterianas/inmunología , Inmunización Pasiva , Salmonelosis Animal/prevención & control , Salmonella enteritidis/inmunología , Administración Oral , Animales , Anticuerpos Antibacterianos/administración & dosificación , Especificidad de Anticuerpos , Adhesión Bacteriana , Western Blotting , Pollos , Modelos Animales de Enfermedad , Yema de Huevo/inmunología , Técnica del Anticuerpo Fluorescente , Intestino Delgado/microbiología , Ratones , Microvellosidades/microbiología , Salmonella enteritidis/patogenicidad , Salmonella enteritidis/ultraestructura , Virulencia
6.
Arch Virol ; 138(1-2): 143-8, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7980004

RESUMEN

The efficacy of chicken egg yolk immunoglobulins (yIg) from hens immunized with bovine rotavirus (BRV) serotype G6 (strain Shimane) or serotype G10 (strain KK-3) for protection against homologous BRV in calves was investigated. A significant protection by anti-BRV yIg having 6400 neutralizing antibody titer per dose could be achieved in calves (P < 0.01).


Asunto(s)
Anticuerpos Antivirales/uso terapéutico , Enfermedades de los Bovinos/prevención & control , Infecciones por Rotavirus/veterinaria , Rotavirus/inmunología , Administración Oral , Animales , Bovinos , Línea Celular , Pollos , Diarrea/prevención & control , Diarrea/veterinaria , Diarrea/virología , Yema de Huevo/inmunología , Inmunización Pasiva/veterinaria , Infecciones por Rotavirus/inmunología , Infecciones por Rotavirus/prevención & control
7.
Poult Sci ; 72(12): 2361-5, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7906035

RESUMEN

The yolk antibodies from chickens and the serum and colostrum antibodies from cows were obtained after immunization of these animals with inactivated bacterin or purified K99 fimbriae from enterotoxigenic Escherichia coli (ETEC). The avidity of anti-K99 fimbriae antibodies produced from either chickens or cows was measured by competitive binding assay of ELISA. The yolk antibodies competed strongly with the serum and colostrum antibodies from immunized cows and inhibited 40 to 80% of the binding of these antibodies. Results demonstrate that the avidity of antibodies obtained from immunized chickens compares with that obtained from immunized cows. Thus, the yolk antibody from immunized chickens, aside from its use for prophylaxis against some infectious diseases, may also serve as effective ligand for purification of biologically active substances such as fimbrial antigens by affinity chromatographic procedures.


Asunto(s)
Anticuerpos/metabolismo , Afinidad de Anticuerpos/inmunología , Bovinos/inmunología , Pollos/inmunología , Yema de Huevo/inmunología , Escherichia coli/inmunología , Fimbrias Bacterianas/metabolismo , Animales , Anticuerpos/análisis , Anticuerpos/sangre , Calostro/inmunología , Femenino , Embarazo
8.
Vet Microbiol ; 37(1-2): 135-46, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8296443

RESUMEN

Chicken egg yolk immunoglobulins (yIg) specific against bovine rotavirus (BRV) serotypes 6 (strain Shimane) and 10 (strain KK-3) were used for oral passive immunization of suckling mice against experimental BRV challenge. The protective capacity of the antibody preparation was tested using different concentrations of yIg against a challenge dose of 10(7.5) TCID50 for Shimane and 10(7.0) TCID50 for KK-3 strain. There was a significant homotypic (P < 0.05) and heterotypic (P < 0.01) protection using 160 anti-Shimane or 160 anti-KK-3 neutralizing antibody titer (NAT) compared to control mice given yIg derived from eggs of mock-immunized (control) hens. The titer of infectious BRV recovered from intestinal tissue or luminal chyme decreased with increasing homotypic yIg NAT. A decrease in degree and duration of BRV antigen localization in the villus epithelial lining was observed in mice treated with homotypic yIg at optimum dose for prevention of diarrhea. The NAT in sera of challenged mice increased with decreasing NAT in the yIg given before challenge suggesting that protection was dose-dependent. The present findings indicate that a passive protection could be achieved by the use of yIg against BRV-induced diarrhea in this murine model.


Asunto(s)
Enfermedades de los Bovinos/prevención & control , Diarrea/veterinaria , Inmunización Pasiva/veterinaria , Inmunoglobulinas/inmunología , Infecciones por Rotavirus/veterinaria , Animales , Anticuerpos Antivirales/biosíntesis , Antígenos Virales/análisis , Bovinos , Enfermedades de los Bovinos/microbiología , Pollos , Reacciones Cruzadas , Diarrea/microbiología , Diarrea/prevención & control , Modelos Animales de Enfermedad , Yema de Huevo/inmunología , Femenino , Intestinos/microbiología , Ratones , Infecciones por Rotavirus/inmunología , Infecciones por Rotavirus/prevención & control
9.
Am J Vet Res ; 54(6): 867-72, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8323054

RESUMEN

Chicken egg yolk IgG can be absorbed and transferred as efficiently as colostral antibodies in the blood of neonatal pigs. Egg yolk IgG has a half-life of 1.85 days in newborn pig serum. This is shorter than the reported half-life (12 to 14 days) of homologous IgG in serum of pigs. Similar to colostral antibodies, egg yolk IgG absorption from intestine ceased at about 34 hours of age, after a logarithmic decrease in absorption rate from birth. Egg yolk IgG absorption inhibition time in the gastrointestinal tract took 1.73 hours to decrease by half. Egg yolk IgG was protective against experimentally induced diarrhea in pigs when it was administered at high dose, and multiple dosing was instituted. Adverse effects were not observed when chicken egg yolk IgG was administered orally to pigs.


Asunto(s)
Sistema Digestivo/metabolismo , Inmunoglobulinas/metabolismo , Porcinos/metabolismo , Administración Oral , Animales , Anticuerpos Antibacterianos/metabolismo , Pollos , Yema de Huevo , Ensayo de Inmunoadsorción Enzimática/veterinaria , Escherichia coli/inmunología , Infecciones por Escherichia coli/prevención & control , Infecciones por Escherichia coli/veterinaria , Femenino , Técnica del Anticuerpo Fluorescente/veterinaria , Inmunización Pasiva/métodos , Inmunización Pasiva/veterinaria , Inmunoglobulina G/metabolismo , Absorción Intestinal/fisiología , Enfermedades de los Porcinos/prevención & control
10.
Am J Vet Res ; 53(11): 2005-8, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1466492

RESUMEN

The protective effects of egg yolk powder prepared from hens vaccinated with heat-extracted antigens from K99-piliated enterotoxigenic Escherichia coli (ETEC) strain 431 were evaluated in a colostrum-fed calf model of ETEC-induced diarrhea caused by a heterologous strain (B44). The antibody powder was obtained by spray-drying the water-soluble protein fraction of egg yolks after removing the lipid and fatty components by precipitation with hydroxypropylmethylcellulose phthalate. A total of 16 colostrum-fed calves were studied to determine whether the orally administered antibody powder would prevent fatal bovine colibacillosis caused by a virulent ETEC strain. Clinical response of individual calves was monitored and evaluated in the context of these variables: fecal consistency score, intestinal colonization, weight loss, and mortality. Control calves that were treated with vehicle (milk with egg yolk powder from nonimmunized hens) had severe diarrhea and dehydration and died within 72 hours after infection was manifested. In contrast, calves fed milk containing egg yolk powder with antipili agglutinin titers of 1:800 and 1:1,600 had transient diarrhea, 100% survival, and good body weight gain during the course of the study. Results indicate that the orally administered egg yolk powder protected against ETEC-induced diarrhea in neonatal calves and that the protective components may have been the antibodies raised by vaccination of chickens against ETEC.


Asunto(s)
Animales Recién Nacidos/inmunología , Enfermedades de los Bovinos/prevención & control , Diarrea/veterinaria , Yema de Huevo/inmunología , Infecciones por Escherichia coli/veterinaria , Inmunización Pasiva/veterinaria , Animales , Animales Recién Nacidos/microbiología , Anticuerpos Antibacterianos/inmunología , Antígenos Bacterianos/inmunología , Bovinos , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/microbiología , Pollos , Diarrea/microbiología , Diarrea/prevención & control , Enterotoxinas/inmunología , Escherichia coli/inmunología , Infecciones por Escherichia coli/inmunología , Infecciones por Escherichia coli/prevención & control , Femenino
11.
Infect Immun ; 60(3): 998-1007, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1347289

RESUMEN

Passive protection of neonatal piglets against fatal enteric colibacillosis was achieved with powder preparations of specific antibodies against K88, K99, and 987P fimbrial adhesins of enterotoxigenic Escherichia coli. The antibody powders were obtained by spray drying the water-soluble protein fraction of egg yolks from immunized hens after the lipid components were precipitated with an aqueous dispersion of acrylic resins (Eudragit L30D-55; Rohm pharma). The anti-K88, -K99, and -987P antibody preparations reacted specifically against the corresponding fimbrial antigens in an enzyme-linked immunosorbent assay. The orally administered antibodies protected in a dose-dependent fashion against infection with each of the three homologous strains of E. coli in passive immunization trials with a colostrum-deprived piglet model of enterotoxigenic E. coli diarrhea. Scanning electron microscopy revealed adherence of enterotoxigenic E. coli in intestinal epithelial surfaces of control piglets, whereas in treated piglets treated with high-titer antibodies, a resistance to bacterial adhesion was observed. An enzyme immunoassay with avidin-biotin complex demonstrated specific local antibody activity in target areas of the small intestines. In vitro, E. coli K88+, K99+, and 987P+ strains adhered equally to porcine duodenal and ileal epithelial cells but failed to do so in the presence of homologous anti-fimbrial antibodies. Absorption of egg yolk antibodies with fimbrial immunosorbent removed the anti-fimbrial antibody fraction and reduced significantly the protective nature of the antibody preparation in a passive immunization experiment, suggesting that anti-fimbrial antibodies were the active components.


Asunto(s)
Anticuerpos/inmunología , Yema de Huevo/inmunología , Infecciones por Escherichia coli/prevención & control , Inmunización Pasiva , Animales , Animales Recién Nacidos , Adhesión Bacteriana , Bovinos , Escherichia coli/aislamiento & purificación , Heces/microbiología , Fimbrias Bacterianas/inmunología , Intestino Delgado/microbiología , Conejos , Porcinos
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