DCV - Comunicação em Conferência

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    Antimicrobial resistance and resistance genes in Aeromonas isolated from “alheira”: a traditional portuguese fermented sausage
    2008 - Fontes, M. C.; Saavedra, M. J.; Martins, C.; Martínez-Murcia, A. J.
    Aeromonas are autochthonous species in aquatic environment and have also been isolated from different kinds of foods, including those of animal origin, seafood and vegetables. Some species are considered important pathogens and water and foods are important sources of transmission of Aeromonas spp.. In the present work we studied the antimicrobial resistance in strains of Aeromonas isolated from “alheira”, a traditional Portuguese meat sausage naturally-fermented and smoked, and the occurrence of β-Lactamases genes among these strains. A total of 84 presumptive Aeromonas spp. isolates were obtained from 10 samples purchased in different local markets and subjected to genotyping ERIC-PCR analysis. The 20 strains showing differences in the ERIC-pattern were identified by gyrB gene sequencing and tested against 27 antimicrobial agents. β-Lactamases-encoding genes were detected by PCR using primers for detection of TEM, SHV, OXA, CTX-M, FOX and MOX variants and for the metallo-β-lactamases CphA and VIM. Tested antibiotic susceptibilities in these strains indicated a noticeable level of resistance to several groups of antibiotics. One strain of Aeromonas media harboured blaCTX-M, blaTEM and blaFOX genes. blaOXA-aer and blaFOX were detected in 12 of the 20 strains tested, and blaCphA gene in 8 strains. blaOXA-C gene was detected in 2 strains, one of Aeromonas caviae and other of Aeromonas hydrophila. blaOXA-B was presented in one strain of Aeromonas caviae. There was no evidence for the presence of blaSHV and blaVIM genes in any isolate.
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    Cognitive and Neurodegenerative Effects of the Medetomidine/Ketamine Anesthesia Combination in Mice
    2010 - Ribeiro, Patrícia; Valentim, Ana; Rodrigues, Paula; Antunes, Luís
    Background: Medetomidine (MED)/Ketamine (KET) is a commonly used combination in laboratory animals. Several studies have shown that KET can enhance neuronal death in neonates (1). Nerveless, little is known about its effect in combination with Med and in adult. The aim of this work was to study the effect of different concentrations of MED/KET in cognition and its potential neurodegenerative effect in adult mice. Methods: Fifty-two mice males, inbred C57BL/6, with 28 weeks old, were divided into 4 different groups (I- saline, II-1mg/kg MED, III-1mg/kg MED + 25mg/kg KET, IV-1mg/kg MED + 75mg/kg KET). Drugs were administered intraperitoneally (i.p.). After one hour, anesthesia was reversed with atipamazole 1mg/kg (i.p.). Thirty-two animals (n=8 per group) were behavioral tested with the T-maze task (28 h, 1 and 2 weeks after anesthesia) and open field (24 h after anesthesia). The remaining 20 animals (n=5 per group) were sacrificed 3 hours after anesthesia by cervical dislocation followed by decapitation and their brains analyzed by hemotoxylin-eosin staining and caspase-3 activation to access neurodegeneration in the retrosplenial cortex, visual cortex, pyramidal cell layer from CA1 and CA3 areas of the hippocampus, and in the granular layer of the dentate gyrus. Death cells (H&E) and cells showing clear positive immunoreactions (caspase-3) were counted. Statistical analysis was performed using univariate ANOVA. Results: No significant differences were detected between groups on the behavior performance of the T-maze and open field. These observations were supported by similar results with histopatological studies (H&E and caspase 3 activation, Figure 1).[figure1]Figure 1- Caspase-3 activation (C3A) positive profile per mm2 (number of apoptotic cells) in retrosplenial cortex, visual cortex, pyramidal cell layer of the CA1 (CA1) and CA3(CA3) fields from the hippocampus and granular layer of the dentate gyrus (gyrus). Data showed as average + standard deviation per mm2; n= 5. Group I- saline; Group II - 1mg/kg medetomidine; group III- 1 mg/kg medetomidine + 25mg/kg ketamine; group IV- 1mg/kg medetomidine + 75 mg/kg ketamine. Conclusion: This study showed no cognitive impairment or neurodegenerative differences induced by different concentrations of MED/KET anesthesia in the brain of adult mice.
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    Different Concentrations of Ketamine did not Affect Cognition or Neurodegeneration in Adult Mice
    2011 - Ribeiro, Patrícia; Valentim, Ana; Rodrigues, Paula; Antunes, Luís
    Background: Ketamine is used in clinic how anesthetic and analgesic agent (1). However, little is known about the effects of the acute administration of this drug in brain of adult mice. The aim of this work was to study the effect of different concentrations of ketamine on cognition and its neurodegenerative effects. Methods: Forty-eight mice males, inbred C57BL/6, with 28 weeks old, were divided into 4 different groups (I- saline, II-25 mg/kg ketamine (KET), III-75mg/kg KET, IV-150mg/kg KET). Drugs were administered intraperitoneally (i.p.). Twenty-eight animals (n=7 per group) were behavioral tested with the Radial-maze task (during 12 consecutive days after anesthesia). Number of reference memory and working memory errors and time to finish the test were checked. The remaining 20 animals (n=5 per group) were sacrificed 3 hours after anesthesia by cervical dislocation followed by decapitation and their brains analyzed by hemotoxylin-eosin staining and caspase-3 activation to access neurodegeneration in the retrosplenial cortex, visual cortex, pyramidal cell layer from CA1 and CA3 areas of the hippocampus, and in the granular layer of the dentate gyrus. Death cells (H&E) and cells showing clear positive immunoreactions (caspase-3) were counted. Statistical analysis was performed using univariate ANOVA. Results: No significant differences were detected between groups on the behavior performance of the Radial-maze (fig.1). These observations were supported by similar results with histopatological studies (H&E and caspase 3 activation). Conclusion: This study showed no cognitive impairment or neurodegenerative differences induced by different concentrations of ketamine in the brain of adult mice.
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    Preovulatory LH peak and time of ovulation in nulliparous and primiparous goats after male effect
    2008 - Simões, João; Baril, Gérard; Cunha, Teresa; Azevedo, Jorge Manuel Teixeira de; Mascarenhas, Ramiro
    The aim of the present study was to determine the time of preovulatory LH peak and ovulation in anoestrous goats, after stimulation by male effect. Seven nulliparous and eight primiparous Serrana goats were isolated from bucks during nonbreeding season. Anoestrus was confirmed by circulating progesterone levels. A 6-day progestagen treatment (Chronogest® 45 mg FGA, Intervet, Holland) was performed to synchronize oestrus on early May. Vaginal sponges were removed at the time of buck introduction (BI). Plasma LH levels were determined (ELISA), every 4 h, through 24 h after onset of oestrus and total number of ovulations were detected by transrectal ultrasonography, every 8 h, until 44 h. No significant differences (P > 0.05) were observed between nulliparous and primiparous goats for the interval between BI and onset of oestrus (50.6 ± 3.6 h vs 45.6 ± 2.9 h), preovulatory LH peak (54.9 ± 3.2 h vs 55.5 ± 3.8 h) or ovulation (77.7 ± 3.0 h vs 78.3 ± 3.6 h). However, the interval between the onset of oestrus and preovulatory LH peak was lower in nulliparous (4.3 ± 0.8 h) than in primiparous (10.5 ± 2.4 h; P < 0.05) goats. The interval between the onset of oestrus and ovulation was also lower in nulliparous (27.1 ± 1.4 h) than primiparous (33.3 ± 2.3 h; P < 0.05) goats. The interval between preovulatory LH peak and ovulation was constant between nulliparous (22.9 ± 1.5 h) and primiparous goats (22.8 ± 1.7 h; P > 0.05). In conclusion, these results showed that nulliparous ovulate, in average, early than primiparous goats regarding the onset of oestrus.
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    Seroprelavence of bovine viral diarrhea of beef cows in the portuguese Baixo Alentejo region
    2010 - Canário, Rodrigo; Simões, João; Matos, Miguel; Mira, José
    The Bovine Viral Diarrhea is a cause of important production and reproduction losses in dairy and beef cows exploitations. The aim of the present study was to determine the seroprelavence of beef cows in farms of the Baixo Alentejo, a south region of Portugal. A total of 3622 cows originated in 20 extensive beef farms were used. From this pool, a sample 111 animals greater than one old year were randomized using the n=[1-(α)1/D]x[N-D/2]+ 1 formula in each exploitation. The ELISA INGEZIM BVD Compac® Kit (INGENASA, Imunologia e Genética Aplicada, S.A., Madrid, Spain) was used to determine the anti-BVDV antibody. The result of each animal was considered positive, negative or indeterminate if the optical density was lower than positive cut off, higher than negative cut off or between these values, respectively. The Pearson Chi-square, contingency coefficient and Cramer´s V tests were used. A tendency (P=0.06) for a higher number of farms (65%) with positive animals than farms (35%) with negative animals was observed. However, a significant effect (P< 0.01) between the exploitation and the seroprevalence was observed. A variation from 20% to 100% of positive animal affected from the sample was observed in the 12 affected farms. A correspondence of 75% of positive animal was observed in the percentile 50. This suggests the presence of, at least, an animal persistently infected in each of these exploitations. Due to these results, we conclude that these affected farms need an improvement of their zootechnic and veterinary management in other to detect and eliminate the potential persistently infected animals and prevent new infections. However, new studies were necessary for estimate the realistic impact of this disease in the beef farms of this region of Portugal.