RESUMEN
The expression patterns of some cytokines were compared by RT-qPCR between lambs with and without Taenia hydatigena larvae vesicular concentrate (ThLVC) administration and subsequent infection with Haemonchus contortus. Lambs that received ThLVC prior to infection with H. contortus showed lower (p < 0.03) cumulative FEC (AUC = 18450 ± 3384) than infected lambs who did not receive ThLVC (AUC = 31081 ± 3277). Lambs infected with H. contortus, in general, overexpressed Th1 and Th2 cytokines in abomasal mucosa and abomasal lymph nodes, which seems to indicate a generalized and nonpolarized activation of the immune response by H. contortus. The main immunomodulatory effects of ThLVC were observed in the abomasal fundic region. The lambs that were given ThLVC prior to infection strongly overexpressed most of the studied cytokines representing the Th1 (IFNγ and IL2) and Th2 profiles (IL4, IL5, IL6 and IL10), proinflammatory cytokines (SOD1 and PRDX6) and IgE receptor; in contrast, lambs that were infected but did not receive ThLVC only moderately overexpressed IFNγ, IL4 and IL6. The absence of the significant overexpression of cytokines in lambs that only received ThLVC suggests that this derived from T. hydatigena does not have a stimulating effect per se; however, the presence of H. contortus did produce the highest expression (p < 0.01) cytokine profile among lambs that received ThLVC prior to infection compared to those who did not receive it, so its effect seems to be immunomodulatory and not only immunostimulatory.
Asunto(s)
Hemoncosis/veterinaria , Haemonchus , Enfermedades de las Ovejas/parasitología , Taenia/metabolismo , Abomaso/inmunología , Animales , Anticuerpos Antihelmínticos , Citocinas/metabolismo , Heces/parasitología , Regulación de la Expresión Génica/inmunología , Hemoncosis/prevención & control , Larva/química , Oviposición , Recuento de Huevos de Parásitos , Ovinos , Enfermedades de las Ovejas/inmunologíaRESUMEN
RATIONALE: Aversive learning and memory are essential to cope with dangerous and stressful stimuli present in an ever-changing environment. When this process is dysfunctional, however, it is associated with posttraumatic stress disorder (PTSD). The endocannabinoid (eCB) system has been implicated in synaptic plasticity associated with physiological and pathological aversive learning and memory. OBJECTIVE AND METHODS: The objective of this study was to review and discuss evidence on how and where in the brain genetic or pharmacological interventions targeting the eCB system would attenuate aversive/traumatic memories through extinction facilitation in laboratory animals and humans. The effect size of the experimental intervention under investigation was also calculated. RESULTS: Currently available data indicate that direct or indirect activation of cannabinoid type-1 (CB1) receptor facilitates the extinction of aversive/traumatic memories. Activating CB1 receptors around the formation of aversive/traumatic memories or their reminders can potentiate their subsequent extinction. In most cases, the effect size has been large (Cohen's d ≥ 1.0). The brain areas responsible for the abovementioned effects include the medial prefrontal cortex, amygdala, and/or hippocampus. The potential role of cannabinoid type-2 (CB2) receptors in extinction learning is now under investigation. CONCLUSION: Drugs augmenting the brain eCB activity can temper the impact of aversive/traumatic experiences by diverse mechanisms depending on the moment of their administration. Considering the pivotal role the extinction process plays in PTSD, the therapeutic potential of these drugs is evident. The sparse number of clinical trials testing these compounds in stress-related disorders is a gap in the literature that needs to be addressed.
Asunto(s)
Reacción de Prevención/efectos de los fármacos , Cannabinoides/uso terapéutico , Trastornos por Estrés Postraumático/tratamiento farmacológico , Trastornos por Estrés Postraumático/psicología , Amígdala del Cerebelo/efectos de los fármacos , Amígdala del Cerebelo/metabolismo , Animales , Reacción de Prevención/fisiología , Cannabinoides/farmacología , Extinción Psicológica/efectos de los fármacos , Extinción Psicológica/fisiología , Miedo/efectos de los fármacos , Miedo/fisiología , Miedo/psicología , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Humanos , Plasticidad Neuronal/efectos de los fármacos , Plasticidad Neuronal/fisiología , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/metabolismo , Trastornos por Estrés Postraumático/metabolismoRESUMEN
We evaluated the direct effects of progesterone on the morphology, maturation and behavior of Haemonchus contortus larvae in vitro. The presence and location of possible progesterone receptors in these larvae were also determined. The addition of 8ng/mL of progesterone to larval cultures over 10days reduced larval enlargement, while the addition of 160ng/mL of the hormone increased the enlargement. Up to 62% and 65% of the H. contortus larvae molted from third-stage larvae (L3) to fourth-stage larvae (L4) when cultured in RPMI-1640 media without hormone for 5 and 10days, respectively. The addition of different progesterone concentrations (1, 8, 16, 80 and 160ng/mL) to the larval cultures significantly inhibited the molting process within the same periods. The addition of 8ng/mL or higher progesterone concentrations to the cultures significantly increased larval motility (p<0.05) compared with unstimulated larvae. Flow cytometry showed the expression of progesterone receptors (P4-R) in 15% of the cells from newly isolated H. contortus larvae. When the larvae were cultured for 5days in the presence of the hormone, the percentage of P4-R+ cells remained the same. In contrast, unstimulated larvae showed a significant reduction in the number of P4-R+ cells. Using confocal microscopy, a greater concentration of P4-Rs was immunolocated in the anterior portion of the alimentary tract of the larvae, suggesting that the cells in this region are targeted by the hormone. The results of the present study show that H. contortus larvae have possible P4-Rs and respond to this hormone by inhibiting their molting process, thereby suggesting the participation of progesterone in the larval arrest phenomenon.
Asunto(s)
Haemonchus/efectos de los fármacos , Progesterona/administración & dosificación , Progestinas/administración & dosificación , Animales , Relación Dosis-Respuesta a Droga , Haemonchus/genética , Haemonchus/crecimiento & desarrollo , Haemonchus/metabolismo , Larva/efectos de los fármacos , Larva/genética , Larva/crecimiento & desarrollo , Larva/metabolismo , Muda/efectos de los fármacos , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismoRESUMEN
The abomasal expression of IL-2, IL-4, IL-6, IL-10 and IFNγ in lambs experimentally infected with Haemonchus contortus and its relationship to protection induced by a Taenia hydatigena larvae vesicular concentrate (ThLVC) were evaluated. The lambs that were only infected with H. contortus larvae showed a worm burden greater (p<0.05) than the lambs that received ThLVC prior to infection. Moreover, the lambs that received ThLVC showed a greater (p<0.05) number of blood eosinophils than the lambs that did not receive the ThLVC. In general, the lambs that received ThLVC prior to infection had a greater amount of eosinophils and mast cells and higher in situ expression of IFNγ, IL-2, IL-4, IL-6 and IL-10 in the abomasal wall than the lambs that were infected with H. contortus only or that received ThLVC (p<0.05) only. A higher expression of IL-2 and IFNγ in the submucosa compared to the abomasal mucosa and a higher expression of IL-4 in the abomasal mucosa compared to the submucosa was observed (p<0.05). These results suggest that there is a Th1 type response in the abomasal submucosa and a Th2 type response in in the abomasal mucosa. The amount of eosinophils and mast cells and the in situ expression of IFNγ, IL-2, IL-4 and IL-6 in the abomasal walls were negatively correlated with the worm burden (p<0.05). These results suggest that ThLVC is a non-specific immune stimulator for the abomasal immune response, and it is likely that the protection observed is the result of this effect.
Asunto(s)
Citocinas/inmunología , Hemoncosis/veterinaria , Haemonchus/inmunología , Enfermedades de las Ovejas/inmunología , Taenia/inmunología , Abomaso/inmunología , Animales , Eosinófilos/inmunología , Femenino , Hemoncosis/inmunología , Recuento de Leucocitos/veterinaria , Masculino , Mastocitos/inmunología , Recuento de Huevos de Parásitos/veterinaria , OvinosRESUMEN
The effects of six new synthetic carbamates on fully engorged females of four Rhipicephalus microplus strains (one reference strain susceptible to conventional ixodicides, two strains multiresistant to ixodicides and one tick field isolate) were compared. In addition, the effect of two other new synthetic carbamates was tested on larvae from the same strains. The first six tested carbamates reduced egg laying and inhibited egg hatching in the four studied strains (P<0.05). Compared with untreated females, the eggs produced by the treated engorged female ticks of all strains had a dark, dry, opaque appearance and were less adherent. The remaining two tested carbamates induced larval mortality in all of the evaluated strains. The three studied R. microplus strains displayed 50% resistance ratios (RR50) of less than 2 when compared to the susceptible reference strain. These results demonstrate that both carbamates with a larvicidal effect and carbamates that inhibit egg laying and embryo development are efficacious against tick strains that are resistant to commercial ixodicides, no cross resistance was observed.
Asunto(s)
Acaricidas/farmacología , Carbamatos/farmacología , Rhipicephalus/efectos de los fármacos , Uretano/farmacología , Animales , Resistencia a Medicamentos/efectos de los fármacos , Femenino , Larva/efectos de los fármacos , Oviposición/efectos de los fármacos , Cigoto/efectos de los fármacosRESUMEN
The effect of carbamates on engorged female Rhipicephalus microplus ticks and larvae was evaluated using the adult immersion test (AIT) and the larval packet test (LPT), respectively. Seventeen synthetic carbamates different from current commercial acaricides were synthesised at the National Autonomous University of Mexico. None of the carbamates had an effect on the percentage of females laying eggs. Six of the compounds inhibited egg laying up to 65.4% and inhibited egg hatching by up to 100% (p<0.05). Compared to untreated females, eggs produced by treated females had a dark, dry, opaque appearance and were less adherent. Carbamates LQM 934 and LQM 938 had an effect on larval mortality (p<0.05). Carbamate LQM 934 showed lethal concentrations (LC) of LC90=0.76% and LC99=0.87%, while LQM 938 showed concentrations of LC90=0.267% and LC99=0.305%. The compounds were distributed into three classes of acaricidal activity using the AIT or the LPT. These three classes were as follows: (1) compounds having no apparent effect; (2) compounds that inhibit egg laying and embryo development or (3) compounds that exhibit acaricidal activity to larval ticks.
Asunto(s)
Acaricidas/farmacología , Carbamatos/farmacología , Oviposición/efectos de los fármacos , Rhipicephalus/efectos de los fármacos , Animales , Femenino , Larva/efectos de los fármacos , Larva/fisiología , México , Óvulo/efectos de los fármacos , Óvulo/fisiología , Rhipicephalus/crecimiento & desarrollo , Rhipicephalus/fisiologíaRESUMEN
The aim of this study was to fractionate and partially characterize the antigenic extract of filariform larvae of Strongyloides venezuelensis in ion-exchange resin diethylaminoethyl sepharose (DEAE), to obtain antigenic fractions potentially applicable in immunoassays. Somatic antigen (SA) and its fractions DEAE S1 and DEAE S2 - which interacted with the resin - were evaluated by 1-dimensional electrophoresis to obtain protein profiles. SA and its fractions were tested in serum samples for IgG detection by ELISA. Serum samples (n = 155) were analysed: 50 from strongyloidiasis patients (G1), 55 from patients with other parasitic infections (G2) and 50 from healthy volunteers. Sensitivity (Se), specificity (Sp), area under curve (AUC) and likelihood ratios (LR) were calculated. The DEAE S2 fraction provided a high diagnostic value for IgG detection (Se 92·0%, Sp 91·4%, AUC 0·981, LR+ 10·75, LR - 0·09). In conclusion, the DEAE S2 fraction would probably be a source of immunodominant polypeptides for IgG detection in human strongyloidiasis serodiagnosis.
Asunto(s)
Antígenos Helmínticos , Cromatografía por Intercambio Iónico , Strongyloides/química , Estrongiloidiasis/diagnóstico , Animales , Ensayo de Inmunoadsorción Enzimática/normas , Humanos , Inmunoglobulina G/sangre , Larva/química , Sensibilidad y Especificidad , Pruebas Serológicas , Suero/parasitologíaRESUMEN
The effect of experimental haemonchosis on the number of tissue eosinophils, plasma cells and lymphocyte subpopulations was evaluated in the fundic abomasal region, the pyloric abomasal region and the abomasal lymph node of Blackbelly lambs, which are resistant to infection, and Columbia lambs, which are susceptible to infection. An increase in the number of tissue eosinophils and CD4+ and WC1(+)γδ T-cells was observed in the pyloric abomasal region of Blackbelly lambs and correlated with lower worm burden and greater resistance to infection. Increases in IgA+ plasma cells from the pyloric abomasal region were observed in both infected groups, but there was no difference between the groups. Therefore, increases in IgA+ plasma cells did not explain the resistance observed. Infection caused a significant increase in tissue eosinophils in the abomasal lymph node of Blackbelly lambs and a decrease in the number of CD4+ T-cells in lambs of both breeds. CD8+ T-cells and IgG+ and IgM+ plasma cells were not associated with either infection or resistance. In this work, clear differences were observed in the numbers of CD4+ and WC1(+)γδ T-cells, tissue eosinophils and IgA+ plasma cells between the abomasal regions studied. These differences indicate that the immunological response is not homogenous in all abomasal mucosa and that evaluating the response from a single abomasal region may not be representative of the cellular response across the abomasum.
Asunto(s)
Abomaso/inmunología , Hemoncosis/veterinaria , Haemonchus/clasificación , Enfermedades de las Ovejas/parasitología , Abomaso/citología , Animales , Anticuerpos Antihelmínticos/metabolismo , Heces/parasitología , Predisposición Genética a la Enfermedad , Hemoncosis/inmunología , Haemonchus/inmunología , Inmunoglobulina A/metabolismo , Masculino , Recuento de Huevos de Parásitos , Ovinos , Enfermedades de las Ovejas/genética , Enfermedades de las Ovejas/inmunología , Linfocitos T/clasificación , Linfocitos T/fisiología , Factores de TiempoRESUMEN
The effect of Taenia hydatigena larvae vesicular concentrate (ThLVC) on the establishment of an experimental infection by Haemonchus contortus was evaluated. The lambs that received ThLVC showed a greater (P<0.05) average of blood eosinophils (BE) than the lambs that did not receive ThLVC. Lambs that were only infected with H. contortus larvae showed a fecal egg count (FEC) and an adult phase (AP) number greater (P<0.05) than lambs that received ThLVC prior to infection. No effect was observed in size and prolificacy of AP after the administration of ThLVC. The infection with H. contortus caused an increase (P<0.05) in CD4+ lymphocytes in abomasal lymph node (ALN) and the combination of ThLVC plus the infection with H. contortus caused an increase (P<0.05) in CD4+ lymphocytes in the abomasal wall (AW). In addition, a positive correlation between gamma-delta lymphocytes of ALN (r=0.73, P<0.05) with the presence of AP in the abomasum was observed. The quantity of plasma cells in ALN and AW was not affected by the administration of ThLVC nor related to the resistance observed. The results shown in this work leave no doubt that ThLVC administration prior to inoculation produces eosinophilia and partially protects against the establishment of H. contortus. However, this protection is not only attributable to the role of eosinophils, since ThLVC can function stimulating other immune response cells, such as T lymphocytes, both contributing to prevent the presence of worms.
Asunto(s)
Enfermedades Gastrointestinales/veterinaria , Hemoncosis/veterinaria , Haemonchus/inmunología , Enfermedades de las Ovejas/parasitología , Taenia/inmunología , Abomaso/parasitología , Animales , Anticuerpos Antihelmínticos/sangre , Eosinófilos/inmunología , Heces/parasitología , Enfermedades Gastrointestinales/inmunología , Enfermedades Gastrointestinales/parasitología , Hemoncosis/inmunología , Hemoncosis/parasitología , Masculino , Recuento de Huevos de Parásitos/veterinaria , Ovinos , Enfermedades de las Ovejas/inmunología , Estadísticas no ParamétricasRESUMEN
Twelve healthy horses were subject to the monoioidoacetate (MIA) carpitis model, which was allowed to develop for 7 days. The horses were then randomly divided into two groups. Group A (control) received an intramuscular injection of normal saline every 4 days for a total of seven injections while group B received 500 mg of a PSGAG (SYNTEX CSY36) intramuscularly every 4 days for seven treatments. Efficacy of the PSGAG was evaluated by three clinical outcomes: lameness score, carpal circumference and maximum carpal flexion. Clinical outcomes were measured on days -8 (previous to carpitis induction), 0 (previous to drug treatment), 7, 14, 21, 28 and 35. Areas under the curve clinical outcome as function of time were built and used as variables for the statistical analysis. There was less joint circumference enlargement and lameness and greater carpal flexion in PSGAG-treated horses compared with that in controls. The studied compound has demonstrated to be efficacious on the treatment of a chemically induced carpitis in horses.
Asunto(s)
Artritis/veterinaria , Articulaciones del Carpo/efectos de los fármacos , Glicosaminoglicanos/uso terapéutico , Enfermedades de los Caballos/tratamiento farmacológico , Cojera Animal/tratamiento farmacológico , Animales , Artritis/tratamiento farmacológico , Articulaciones del Carpo/patología , Modelos Animales de Enfermedad , Glicosaminoglicanos/administración & dosificación , Glicosaminoglicanos/normas , Enfermedades de los Caballos/patología , Caballos , Inyecciones Intramusculares/veterinaria , Resultado del TratamientoRESUMEN
Pharmacokinetic parameters were established for enantiomers of the nonsteroidal anti-inflammatory drug (NSAID) ketoprofen (KTP) administered as the racemic mixture at a dose of 2.2 mg/kg and as separate enantiomers, each at a dose of 1.1 mg/kg to a group of six horses (five mares and one gelding). A four-period cross-over study in a LPS-induced model of acute synovitis was used. After administration of the racemic mixture S(+)KTP was the predominant enantiomer in plasma as well as in synovial fluid. Unidirectional inversion of R(-) to S(+)KTP was demonstrated but the inversion was less marked than previously reported. It is suggested that this reduction could be because of the influence of the inflammatory reaction on hepatic metabolism. The disposition of KTP enantiomers after administration of the racemic mixture was similar to those observed after administration of S(+) and R(-)KTP. The S(+) and R(-)KTP concentrations in synovial fluid were low and short lasting. After administration of R(-)KTP significant concentrations of the optical antipode were detected in synovial fluid.