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1.
Phys Rev Lett ; 116(11): 112501, 2016 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-27035296

RESUMEN

Two pairs of positive-and negative-parity doublet bands together with eight strong electric dipole transitions linking their yrast positive- and negative-parity bands have been identified in ^{78}Br. They are interpreted as multiple chiral doublet bands with octupole correlations, which is supported by the microscopic multidimensionally-constrained covariant density functional theory and triaxial particle rotor model calculations. This observation reports the first example of chiral geometry in octupole soft nuclei.

2.
J Wound Care ; 25(7): 384-92, 2016 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-27410392

RESUMEN

OBJECTIVE: To investigate the feasibility of recruitment, retention, intervention delivery and outcome measurement in a nutritional intervention to promote pressure ulcer healing in an acute setting. METHOD: Some 50 tertiary hospital patients with stage II or greater pressure ulcer were randomised to receive either individualised nutritional care by a dietitian, including prescription of wound healing supplements; or standard nutritional care. Relevant nutritional and pressure ulcer (PU) parameters were collected at day 5, 10, 15, 22 and then weekly or until discharge. RESULTS: The median length of hospital stay was 14 days (1-70) with 29 patients discharged by day 15. There were 24 patients discharged before their PU fully healed. Per cent change in valid PU area and score measures from baseline to day 15 were chosen for outcome data analysis to account for varying initial size and severity of the wound and length of stay. There was a larger percentage reduction in PU measures in the intervention group, but this was not statistically significant. Little difference was found in nutritional intake between the control and intervention groups indicating a requirement to focus on effective delivery of the intervention in future studies. Future studies in the acute setting need to account for length of stay and ideally follow patients until full healing. CONCLUSION: Results indicate a positive association with nutrition intervention and PU healing and that a rigorously designed and adequately powered study is feasible. DECLARATION OF INTEREST: This research was supported by a grant from the Queensland Health, Health Practitioner Research Scheme. The authors have no conflicts of interest to declare.


Asunto(s)
Cuidados Críticos/métodos , Suplementos Dietéticos , Tiempo de Internación/estadística & datos numéricos , Terapia Nutricional/métodos , Úlcera por Presión/dietoterapia , Úlcera por Presión/enfermería , Cicatrización de Heridas/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud
3.
Pol J Vet Sci ; 15(1): 3-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22708351

RESUMEN

Toxoplasma gondii is a parasite that has been extensively studied due to its medical and veterinary importance in terminating pregnancies. Consequently, a satisfactory vaccine is required to control its adverse effects on pregnant animals. The microneme protein, MIC3, is a major adhesion protein that binds to the surface of host cells and parasites, and is therefore a potential vaccine against T. gondii. The viability of MIC3 as a vaccine is investigated in this study. Sheep were injected twice, intramuscularly, with plasmids containing DNA encoding for the mature form of MIC3 protein formulated into liposomes. Control sheep were injected with an empty vector or received no injections. The injection of sheep with DNA plasmids encoding for MIC3 elicited an immune response after the first and second injections as indicated by antibody responses and the production of IFN-gamma. The immune response, as measured by the IgG2 and IgG1 serum levels, was boosted after the injection of the MIC3 DNA vaccine together with high anti-MIC3 antibodies. The results demonstrate that the intramuscular injection of sheep with a plasmid containing DNA coding for MIC3 protein induces a significant and effective immune response against T. gondii.


Asunto(s)
ADN Protozoario/inmunología , Proteínas Protozoarias/inmunología , Vacunas Antiprotozoos/inmunología , Enfermedades de las Ovejas/prevención & control , Toxoplasma/inmunología , Toxoplasmosis Animal/prevención & control , Animales , Anticuerpos Antiprotozoarios/sangre , Células CHO , Cricetinae , Regulación de la Expresión Génica , Inmunoglobulina G/sangre , Interferón gamma , Liposomas , Ovinos , Toxoplasma/metabolismo , Vacunación
4.
J Exp Med ; 172(3): 937-45, 1990 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-2117637

RESUMEN

The importance of CD4+ cells in resistance to Pneumocystis carinii (PC) in PC-susceptible severe combined immunodeficient (SCID) mice that were made resistant to PC by immunocompetent spleen cell transfer, and in conventional PC-resistant mice, was investigated. SCID mice with naturally acquired PC pneumonia (PCP) were given infusions of spleen cells from immunocompetent donors. This reconstitution caused the recipients to resolve their PCP. Treatment of reconstituted SCID mice with anti-CD4 monoclonal antibodies (mAbs) to deplete them of CD4+ cells eliminated their ability to resolve PCP, whereas treating them with anti-CD8 mAb to deplete CD8+ cells had no effect. The findings indicate, therefore, that resistance to PCP in immunologically reconstituted SCID mice is dependent on CD4+ cells. To determine whether CD4+ cells enable conventional mice to resist PCP, B6D2 mice were treated with anti-CD4 mAb to deplete them of CD4+ cells in an attempt to induce PCP. After 10-11 wk of treatment, these mice developed progressive PCP. Taken together, these results indicate that loss of CD4+ cells predisposes mice to PC infection.


Asunto(s)
Antígenos CD4/inmunología , Inmunidad Innata , Neumonía por Pneumocystis/inmunología , Animales , Antígenos de Diferenciación de Linfocitos T/análisis , Enfermedades Autoinmunes/genética , Enfermedades Autoinmunes/inmunología , Antígenos CD4/análisis , Antígenos CD8 , Femenino , Pulmón/inmunología , Pulmón/patología , Ratones , Ratones Endogámicos BALB C , Ratones Mutantes , Neumonía por Pneumocystis/patología , Bazo/inmunología , Linfocitos T/inmunología , Linfocitos T/patología , Timectomía
5.
Phys Rev Lett ; 104(14): 142301, 2010 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-20481933

RESUMEN

This Letter presents the first measurement of event-by-event fluctuations of the elliptic flow parameter v(2) in Au+Au collisions at square root(s(NN))=200 GeV as a function of collision centrality. The relative nonstatistical fluctuations of the v(2) parameter are found to be approximately 40%. The results, including contributions from event-by-event elliptic flow fluctuations and from azimuthal correlations that are unrelated to the reaction plane (nonflow correlations), establish an upper limit on the magnitude of underlying elliptic flow fluctuations. This limit is consistent with predictions based on spatial fluctuations of the participating nucleons in the initial nuclear overlap region. These results provide important constraints on models of the initial state and hydrodynamic evolution of relativistic heavy ion collisions.

6.
Phys Rev Lett ; 104(6): 062301, 2010 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-20366815

RESUMEN

A measurement of two-particle correlations with a high transverse momentum trigger particle (p(T)(trig) > 2.5 GeV/c) is presented for Au+Au collisions at square root(s(NN)) = 200 GeV over the uniquely broad longitudinal acceptance of the PHOBOS detector (-4 < Delta eta < 2). A broadening of the away-side azimuthal correlation compared to elementary collisions is observed at all Delta eta. As in p+p collisions, the near side is characterized by a peak of correlated partners at small angle relative to the trigger particle. However, in central Au+Au collisions an additional correlation extended in Delta eta and known as the "ridge" is found to reach at least |Delta eta| approximately = 4. The ridge yield is largely independent of Delta eta over the measured range, and it decreases towards more peripheral collisions. For the chosen (p(T)(trig) cut, the ridge yield is consistent with zero for events with less than roughly 100 participating nucleons.

7.
Parasite Immunol ; 32(9-10): 671-83, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20691019

RESUMEN

Infection with the intracellular protozoan parasite Toxoplasma gondii (T. gondii) causes health problems to both humans and livestock and has a large economic impact worldwide. The immune response in sheep following infection with T. gondii was evaluated using six different combinations of plasmid DNA, recombinant antigen and adjuvant. Sheep were generally vaccinated twice by intramuscular injection with plasmid DNA containing gene sequences for either the surface antigen (SAG1) or the rhoptry protein (ROP1) of T. gondii. Two of the groups injected with plasmid DNA SAG1 were boosted with recombinant protein (SAG1). We investigated the efficacy of including oligodeoxynucleotides (ODN) that contain CG motifs (CpG) and the gene coding for ovine granulocyte-macrophage colony stimulating factor (GM-CSF) as potential adjuvants. Administration of the plasmid encoding the ROP1 gene significantly enhanced both IFN-gamma production from peripheral blood cells when cultured in vitro with Toxoplasma antigen, and ROP1-specific IgG1 and IgG2 antibody levels present in serum. However, injection with SAG1 did not stimulate IFN-gamma production. These results indicate the potential of ROP1, given as plasmid DNA, as a potential vaccine candidate to protect sheep against T. gondii infection.


Asunto(s)
Antígenos de Protozoos/inmunología , Proteínas de la Membrana/inmunología , Proteínas Protozoarias/inmunología , Vacunas Antiprotozoos/inmunología , Toxoplasma/inmunología , Toxoplasmosis Animal/inmunología , Vacunación , Vacunas de ADN/inmunología , Adyuvantes Inmunológicos , Animales , Anticuerpos Antiprotozoarios/sangre , Anticuerpos Antiprotozoarios/inmunología , Especificidad de Anticuerpos , Antígenos de Protozoos/genética , Células Cultivadas , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Esquemas de Inmunización , Inmunoglobulina G/sangre , Inyecciones Intramusculares , Interferón gamma/biosíntesis , Proteínas de la Membrana/genética , Oligodesoxirribonucleótidos/inmunología , Plásmidos/genética , Proteínas Protozoarias/genética , Vacunas Antiprotozoos/administración & dosificación , Vacunas Antiprotozoos/genética , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/inmunología , Ovinos , Toxoplasmosis Animal/sangre , Vacunas de ADN/administración & dosificación , Vacunas de ADN/genética
8.
Vet Parasitol ; 153(3-4): 294-301, 2008 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-18329809

RESUMEN

This study tested the hypothesis that milk has a direct effect on the establishment of infection with Teladorsagia circumcincta, and provides information on the effects of suckling on resilience to infection in young lambs. Of 46 six-week-old twin-born lambs, one from each twin was allowed to continue suckling (S-) and its twin-weaned (W-) while both were concurrently infected with an average of either 0 (-0; n=7/group), 250 (-250; n=8/group) or 1000 (-1000; n=8/group) third stage infective larvae (L3) of T. circumcincta per day, providing six treatment groups. All groups grazed minimally contaminated pasture, and after 42 days were slaughtered for necropsy. Low pasture larval contamination was confirmed in W0 and S0 lambs by faecal egg counts (FEC) of less than 30 eggs per gram (EPG) and burdens of less than 140 worms. There was no difference in FEC between weaned and suckled lambs. Within infection regime, total worm burdens were 55-60% greater in the weaned compared with their suckled counterparts (P=0.05), and represented 27 and 17%, respectively, net establishment of larvae. The greater worm burdens of both groups of weaned animals, which compared with their suckled counterparts, and of those infected with 1000 compared with 250 larvae per day, were associated with shorter female adults that had fewer eggs in utero, perhaps indicating intra-worm population regulation, but highlighting the limitation of FEC in assessing nematode burdens of such young lambs. There was no effect of infection on live weight gain of either weaned or suckled groups and the possibility was raised that, in such young lambs, immune unresponsiveness may be responsible. The major benefit of continued milk consumption appears to lie more in providing nutrients for enhanced growth rather than in improving resilience of the lambs to infection.


Asunto(s)
Animales Lactantes/inmunología , Ostertagiasis/veterinaria , Recuento de Huevos de Parásitos/veterinaria , Enfermedades de las Ovejas/parasitología , Animales , Animales Recién Nacidos , Heces/parasitología , Femenino , Masculino , Ostertagia/patogenicidad , Ostertagiasis/inmunología , Ostertagiasis/parasitología , Distribución Aleatoria , Ovinos , Enfermedades de las Ovejas/inmunología , Destete , Aumento de Peso
9.
Anim Biotechnol ; 18(1): 37-44, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17364442

RESUMEN

Associations between FABP3 (alternatively named H-FABP) gene polymorphisms and fatness traits were tested in two pig breeds (Polish Large White and Polish Landrace) and one synthetic line - 990. Three known single nucleotide polymorphisms, detected by HinfI, MspI and HaeIII restriction enzymes, were analyzed. Moreover, three new polymorphisms in the 5' regulatory region were identified: C(-221)T, C(-160)G and T(-158)G, but only the third one was widely distributed and correlated with backfat thickness in line 990. The obtained results suggest that the FABP3 gene is linked with an unknown gene directly affecting backfat thickness, but the analyzed polymorphisms do not influence fatness traits.


Asunto(s)
Tejido Adiposo/fisiología , Proteínas de Unión a Ácidos Grasos/genética , Porcinos/genética , Animales , Secuencia de Bases , ADN/química , ADN/genética , Femenino , Genotipo , Masculino , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa/veterinaria , Polimorfismo de Nucleótido Simple , Mapeo Restrictivo
10.
J Mol Biol ; 285(4): 1749-63, 1999 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-9917409

RESUMEN

NMR structures of a new toxin from the scorpion Leiurus quinquestriatus hebraeus (Lqh III) have been investigated in conjunction with its pharmacological properties. This toxin is proposed to belong to a new group of scorpion toxins, the alpha-like toxins that target voltage-gated sodium channels with specific properties compared with the classical alpha-scorpion toxins. Electrophysiological analysis showed that Lqh III inhibits a sodium current inactivation in the cockroach axon, but induces in addition a resting depolarization due to a slowly decaying tail current atypical to other alpha-toxin action. Binding studies indicated that radiolabeled Lqh III binds with a high degree of affinity (Ki=2.2 nM) on cockroach sodium channels and that the alpha-toxin from L quinquestriatus hebraeus highly active on insects (LqhalphaIT) and alpha-like toxins compete at low concentration for its receptor binding site, suggesting that the alpha-like toxin receptor site is partially overlapping with the receptor site 3. Conversely, in rat brain, Lqh III competes for binding of the most potent anti-mammal alpha-toxin from Androctonus australis Hector venom (AaH II) only at very high concentration. The NMR structures were used for the scrutiny of the similarities and differences with representative scorpion alpha-toxins targeting the voltage-gated sodium channels of either mammals or insects. Three turn regions involved in the functional binding site of the anti-insect LqhalphaIT toxin reveal significant differences in the Lqh III structure. The electrostatic charge distribution in the Lqh III toxin is also surprisingly different when compared with the anti-mammal alpha-toxin AaH II. Similarities in the electrostatic charge distribution are, however, recognized between alpha-toxins highly active on insects and the alpha-like toxin Lqh III. This affords additional important elements to the definition of the new alpha-like group of scorpion toxins and the mammal versus insect scorpion toxin selectivities.


Asunto(s)
Neurotoxinas/química , Péptidos/química , Venenos de Escorpión/química , Escorpiones/química , Secuencia de Aminoácidos , Animales , Axones/efectos de los fármacos , Axones/metabolismo , Sitios de Unión , Cucarachas , Péptidos y Proteínas de Señalización Intercelular , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Datos de Secuencia Molecular , Neurotoxinas/genética , Neurotoxinas/toxicidad , Péptidos/genética , Péptidos/toxicidad , Conformación Proteica , Estructura Secundaria de Proteína , Ratas , Venenos de Escorpión/genética , Venenos de Escorpión/toxicidad , Escorpiones/genética , Homología de Secuencia de Aminoácido , Canales de Sodio/efectos de los fármacos , Canales de Sodio/metabolismo , Electricidad Estática
11.
FEBS Lett ; 483(2-3): 175-80, 2000 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-11042276

RESUMEN

The two insecticidal peptides Bm32-VI and Bm33-I, isolated from the venom of the Chinese scorpion Buthus martensi induce paralytical symptoms typical of insect contractive toxins. They show, respectively, 74% and 77% homology with AaIT from Androctonus australis, comparable insecticidal activity and no vertebrate toxicity. Under voltage-clamp conditions, both toxins induced (1) an increased fast Na(+) current, (2) a shift in voltage dependence of Na(+) current activation, (3) the occurrence of a delayed current, and (4) a slow development of a holding current. Increased Na(+) conductance at negative potential values is responsible for axonal hyperexcitability and the contractive paralysis of insect prey.


Asunto(s)
Insecticidas/química , Venenos de Escorpión/química , Escorpiones/química , Secuencia de Aminoácidos , Animales , Axones/efectos de los fármacos , Axones/fisiología , Fraccionamiento Químico , Cromatografía Líquida de Alta Presión , Cucarachas , Electrofisiología , Inyecciones Intraventriculares , Insecticidas/farmacología , Masculino , Potenciales de la Membrana/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Venenos de Escorpión/farmacología , Alineación de Secuencia , Análisis de Secuencia de Proteína , Homología de Secuencia de Aminoácido , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Pruebas de Toxicidad
12.
Immunol Lett ; 5(2): 71-4, 1982 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6818137

RESUMEN

Unsensitized human erythrocytes (E) were haemolyzed by bovine serum to a titre of 1:16-1:32. In the single dilution beyond the haemolytic endpoint, the cells were conglutinated. In dilutions in which haemolysis occurred, cells were conglutinated before being lyzed. With no or minimal haemolysis, conglutination to 1:32-1:64 occurred in tests using insulin-absorbed serum, serum heated at 50 degrees C for 30 min and in tests incubated at 4 degrees C for 30 min. In two-stage tests, EDTA and Mg2+-EGTA prevented bovine C sensitization of human E for conglutination by bovine serum heated at 56 degrees C for 30 min. EDTA prevented haemolysis, but haemolysis to 1:16-1:32 occurred with serum dilutions containing Mg2+-EGTA. Haemolytic activity was restored to serum heated at 50 degrees C by a factor B-containing fraction. Conglutination and haemolysis were blocked by heating serum at 56 degrees C for 30 min and were reduced to low titres by absorbing serum with zymosan. These results strongly suggest that the conglutination reaction involved the classical activation pathway whereas the haemolytic reaction involved the alternative activation pathway. Thus, with dilutions of untreated or treated bovine serum, two C-dependent reactions and the pathways involved can be demonstrated by using unsensitized human E as an indicator system.


Asunto(s)
Proteínas del Sistema Complemento/fisiología , Eritrocitos/fisiología , Aglutinación , Animales , Bovinos , Vía Alternativa del Complemento , Vía Clásica del Complemento , Ácido Edético/farmacología , Ácido Egtácico/farmacología , Hemólisis , Humanos , Magnesio/farmacología , Temperatura
13.
Int J Parasitol ; 19(1): 85-9, 1989 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2707966

RESUMEN

Mice were evaluated for immunological responses and resistance to challenge infections after single infections. When given infections simultaneously with thiabendazole, larval migration to the liver and lungs was blocked but not when mice were given infections only. Enlargement of Peyer's patches was observed after infection followed by increased numbers of IgA-containing cells in the lamina propria of the intestines and increased levels of hepatobiliary IgA. Ig-containing cells were variable in the spleens during the early phase of infection. The observed changes quickly returned to normal control levels and did not change throughout the rest of the experiment. Serum Ig levels did not change dramatically. Challenge with high doses of eggs indicated that mice given single very low-dose infections became highly resistant.


Asunto(s)
Ascariasis/inmunología , Ascaris/inmunología , Inmunoglobulinas/biosíntesis , Animales , Femenino , Intestino Delgado/inmunología , Hígado/parasitología , Pulmón/parasitología , Masculino , Ratones , Ratones Endogámicos , Bazo/inmunología
14.
Int J Parasitol ; 20(1): 77-81, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2312230

RESUMEN

Crossbred young pigs were used to test whether abbreviated infections with eggs of Ascaris suum can stimulate the acquisition of resistance to challenge. Weanling pigs from an Ascaris-free colony were kept free of A. suum until they were divided into groups at the age of 7-8 weeks. The experimental animals received pyrantel tartrate during the period when they were being exposed to increasing numbers of infective A. suum eggs and challenged 10 days after the last infective dose. Liver milk-spot counts and larval recoveries from the lungs indicated that the strongest resistance was acquired by the animals that received the drug continuously for 6 weeks while being exposed to six weekly infective egg doses. The data do not suggest any drug-related suppression of the resistance response to A. suum infection.


Asunto(s)
Ascariasis/veterinaria , Ascaris/inmunología , Tartrato de Pirantel/uso terapéutico , Pirantel/análogos & derivados , Enfermedades de los Porcinos/inmunología , Animales , Ascariasis/tratamiento farmacológico , Ascariasis/inmunología , Larva/inmunología , Porcinos , Enfermedades de los Porcinos/tratamiento farmacológico
15.
Int J Parasitol ; 22(5): 597-601, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1399243

RESUMEN

Fifty-four crossbred, 4-week-old pigs divided into nine equal groups were used to test whether multiple inoculations with high numbers of A. suum eggs with or without anthelmintic would result in patent infections. All pigs exposed to multiple prechallenge inoculations of 500, 1000, 2000, 5000, 10,000 and 20,000 and challenged orally 2 weeks later with 10,000 eggs harboured adult worms. When prechallenge infections were removed by pyrantel tartrate treatment the animals were more susceptible to challenge than controls not previously exposed to infections. The same drug used from 2 days before until 10 days after the last prechallenge infection eliminated that effect. Pigs subjected to the same multiple egg dosing regimen but given feed containing fenbendazole immediately before, during and for 10 days after multiple dosing developed significantly more adult intestinal worms after challenge than any other group. These worms were, however, significantly shorter than those that developed in any group of pigs. Adult worms from all these groups produced eggs that after embryonation were infective to mice.


Asunto(s)
Ascariasis/veterinaria , Ascaris suum/inmunología , Enfermedades de los Porcinos/inmunología , Animales , Ascariasis/tratamiento farmacológico , Ascariasis/inmunología , Susceptibilidad a Enfermedades , Femenino , Fenbendazol/uso terapéutico , Tartrato de Pirantel/uso terapéutico , Distribución Aleatoria , Porcinos , Enfermedades de los Porcinos/tratamiento farmacológico
16.
Int J Parasitol ; 24(3): 429-31, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8070963

RESUMEN

The number of mucosal mast cells/globule leukocytes (MMC/GLs) increase in the intestinal mucosa in response to nematode parasite infections but it is not known if this accumulation is due to in situ cell division, derivation from elsewhere or some combination of both. To determine if MMC/GLs can divide, cells were obtained from immunized Romney sheep and cultured in vitro in RPMI 1640. For cultures supplemented with 10, 20 or 30% foetal lamb serum (FLS) or foetal calf serum (FCS) and without concanavalin A (Con A), cell division had ceased by day 2, but with Con A (3 micrograms ml-1) cell division continued to day 9. Better growth of cells was obtained with the higher concentrations of serum. However the use of 30% or 50% autologous serum with Con A lead to cell death but 10% serum permitted limited growth. The detrimental effect of autologous serum could be overcome by increasing the Con A concentration. It was established that an alpha-macroglobulin present in autologous serum can bind Con A. This macroglobulin appears to have a higher avidity for Con A than does the receptor(s) on the surface of MMC/GLs. Our data seem to indicate that a direct interaction of Con A with the cell surface or a receptor(s) is responsible for MMC/GLs division.


Asunto(s)
Mucosa Intestinal/citología , Leucocitos/citología , Mastocitos/citología , Ovinos/fisiología , Animales , División Celular/efectos de los fármacos , Células Cultivadas , Concanavalina A/farmacología , Medios de Cultivo , Sueros Inmunes/fisiología
17.
Int J Parasitol ; 26(4): 445-6, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8773533

RESUMEN

Live eosinophils when mixed with Acridine Orange solution and viewed microscopically using u.v. light show very intense colours of their granules (yellow, orange and red) and green nuclear staining. Their active movement, translocation of granules and degranulation can be observed in vitro. Using this method, live eosinophils can be easily differentiated and enumerated.


Asunto(s)
Gránulos Citoplasmáticos/ultraestructura , Eosinófilos/citología , Naranja de Acridina , Animales , Núcleo Celular/ultraestructura , Gránulos Citoplasmáticos/fisiología , Eosinófilos/química , Mucosa Intestinal/citología , Intestino Delgado , Recuento de Leucocitos , Ovinos , Coloración y Etiquetado/métodos
18.
Int J Parasitol ; 26(1): 97-103, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9198604

RESUMEN

A protective immune response without liveweight loss can be induced in sheep against T. colubriformis but results depend on the anthelmintic used and duration of immunizing infections. More than 90% protection was achieved in sheep immunized by three 15- or 7-day oxfendazole abbreviated infections or three 21-day nonabbreviated infections. Only 41% protection was induced by 3-day oxfendazole abbreviated infections. Significantly higher worm burden and faecal egg counts were present after challenge in sheep immunized by 7-day levamizole abbreviated infections compared to 7-day oxfendazole abbreviated infection. Liveweight gains of sheep immunized by 15- and 7-day abbreviated infections were not significantly different than non infected controls. Liveweight loss seemed to be associated with high activity of mucus peroxidase and high numbers of eosinophils in the intestinal lumen. High parasite numbers seemed to be associated with low activity of alkaline phosphatase in mucus. Mucus peroxidase, arylsulphatase, larval migration inhibition of mucus, mucus or serum antibody against L3 excretory/secretory antigen or somatic L3, L4 and adult antigen were not associated with protection.


Asunto(s)
Anticuerpos Antihelmínticos/sangre , Enfermedades de las Ovejas/prevención & control , Tricostrongiliasis/veterinaria , Vacunación , Fosfatasa Alcalina/análisis , Animales , Antihelmínticos/farmacología , Antígenos Helmínticos/inmunología , Arilsulfatasas/análisis , Bencimidazoles/farmacología , Intestinos/inmunología , Larva , Moco/enzimología , Ovinos , Enfermedades de las Ovejas/tratamiento farmacológico , Enfermedades de las Ovejas/inmunología , Tricostrongiliasis/tratamiento farmacológico , Tricostrongiliasis/inmunología , Tricostrongiliasis/prevención & control , Aumento de Peso
19.
Int J Parasitol ; 24(2): 307-9, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8026913

RESUMEN

Romney sheep, 1-2 years old, immunized by at least three anthelmintic abbreviated infections of 80-100,000 Trichostrongylus colubriformis larvae usually produced high numbers of intestinal mucosal mast cells/globule leukocytes (MMC/GLs). In isolating these cells, the importance of maintaining the intestine at 37 degrees C, removal of mucus with dithiothreitol, enzymatic dispersion and careful in vitro handling procedures for maximising cell viability are emphasised. The MMC/GLs were separated from most contaminant cells by using a Percoll discontinuous gradient. MMC/GLs collected at the 60/100% Percoll interface were passed through a complement coated nylon wood column to remove the contaminating eosinophils. Viable MMC/GLs were able to grow in vitro in the presence of Concanavalin A and survive in culture for up to 30 days. The MMC/GLs were readily identified by ultraviolet light microscopy after staining with auramine O.


Asunto(s)
Intestino Delgado/patología , Leucocitos , Mastocitos , Enfermedades de las Ovejas/inmunología , Tricostrongiliasis/veterinaria , Animales , Separación Celular , Centrifugación por Gradiente de Densidad , Mucosa Intestinal/patología , Ovinos , Tricostrongiliasis/inmunología
20.
Int J Parasitol ; 25(4): 523-9, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7635628

RESUMEN

Blastogenic activity, eosinophil and total white blood cell counts (TWBC) were examined over a period of 14 weeks in Romney lambs, genetically resistant or susceptible to gastrointestinal nematodes. The lambs were infected with 5000 infective Trichostrongylus colubriformis larvae twice weekly. Compared to preinfection levels, the blastogenic activity of unstimulated lymphocytes in lambs of both lines peaked at week 3, and was significantly higher in resistant than in susceptible lambs. These changes may have been due to in vivo polyclonal activation. Lymphocytes from susceptible sheep responded more strongly to Con A, PHA and PWM than cells from resistant sheep. Counts per minute (c.p.m) for Con A- and PHA-stimulated lymphocytes increased in both lines of sheep from week 2 to week 7 and then returned to initial levels. An increase in c.p.m. in PWM-stimulated cell cultures was observed from weeks 3 to 5 in both groups. The blastogenic activity for LPS-stimulated cultures was significantly higher for resistant than susceptible sheep at weeks 3 and 4. No significant correlations between the decline in faecal egg counts (FEC) and the blastogenic activity was observed. Eosinophil counts in peripheral blood began to increase one week earlier in resistant than in susceptible sheep. No significant correlation between FEC and eosinophil counts was observed in resistant lambs, whereas in susceptible lambs a significant correlation was found between FEC and eosinophil counts at some sampling times. TWBC in resistant lambs steadily increased with infections whereas susceptible lambs showed a decrease until week 5 and then steadily increased. There was no significant correlation between the decline in FEC and TWBC.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Parasitosis Intestinales/veterinaria , Enfermedades de las Ovejas/inmunología , Tricostrongiliasis/veterinaria , Trichostrongylus/inmunología , Animales , Eosinofilia/inmunología , Eosinofilia/parasitología , Inmunidad , Inmunidad Innata , Parasitosis Intestinales/inmunología , Parasitosis Intestinales/parasitología , Recuento de Leucocitos , Activación de Linfocitos/inmunología , Masculino , Recuento de Huevos de Parásitos , Ovinos , Enfermedades de las Ovejas/parasitología , Tricostrongiliasis/inmunología , Tricostrongiliasis/parasitología , Trichostrongylus/aislamiento & purificación
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