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- A decomposição do colagénio na carnePublication . Correia, J.H.R.D.O autor realiza ma breve síntese da informação de Bioquímica básica com repercussões imediatas na compreensão do fenómeno da decomposição da proteína colagénio na carne. É realçada a importância do estabelecimento de ligações cruzadas de hidroxipiridinium para a formação de fibras de colagénio e, concomitantemente, para a maior força de corte da carne.
- Management of personal bibliographic reference using a simple database programPublication . Correia, J.H.R.D.Although it has been hard to introduce new ideas for the design and use of bibliographic databases, improvements on the common designs have been required for particular applications.
- A gestão dum arquivo de referências bibliográficas científicas num microcomputador pessoalPublication . Correia, J.H.R.D.O estabelecimento dum sistema de gestão de bases de dados bibliográficos utilizando a linguagem ISIS é descrita. As vantagens comparativas da estrutura actual da base de dados são discutidas, e descritos os algoritmos para a gestão mais apropriada de bases de dados de bibliografia pessoal
- Dynamics of notch pathway expression during mouse testis post-natal development and along the spermatogenic cyclePublication . Murta, Daniel; Batista, Marta; Silva, Elisabete; Trindade, Alexandre; Henrique, Domingos; Duarte, António; Lopes da Costa, LuísThe transcription and expression patterns of Notch pathway components (Notch 1–3, Delta1 and 4, Jagged1) and effectors (Hes1, Hes2, Hes5 and Nrarp) were evaluated (through RT-PCR and IHC) in the mouse testis at key moments of post-natal development, and along the adult spermatogenic cycle. Notch pathway components and effectors are transcribed in the testis and expressed in germ, Sertoli and Leydig cells, and each Notch component shows a specific cell-type and timewindow expression pattern. This expression at key testis developmental events prompt for a role of Notch signaling in prepubertal spermatogonia quiescence, onset of spermatogenesis, and regulation of the spermatogenic cycle.
- Oral Recombinant Feline Interferon-Omega as an alternative immune modulation therapy in FIV positive cats : clinical and laboratory evaluationPublication . Gil, S.; Leal, R.O.; McGahie, D.; Sepúlveda, N.; Duarte, A.; Niza, M.M.R.E.; Tavares, L.Recombinant-Feline Interferon-Omega (rFeIFN-ω) is an immune-modulator licensed for use subcutaneously in Feline Immunodeficiency virus (FIV) therapy. Despite oral protocols have been suggested, little is known about such use in FIV-infected cats. This study aimed to evaluate the clinical improvement, laboratory findings, concurrent viral excretion and acute phase proteins (APPs) in naturally FIV-infected cats under oral rFeIFN-ω therapy (0.1 MU/cat rFeIFN-ω PO, SID, 90 days). 11 FIV-positive cats were treated with oral rFeIFN-ω (PO Group). Results were compared to previous data from 7 FIV-positive cats treated with the subcutaneous licensed protocol (SC Group). Initial clinical scores were similar in both groups. Independently of the protocol, rFeIFN-ω induced a significant clinical improvement of treated cats. Concurrent viral excretion and APP’s variation were not significant in the PO Group. Oral rFeIFN-ω can be an effective alternative therapy for FIV-infected cats, being also an option for treatment follow-up in cats submitted to the licensed protocol.
- Myogenic oscillations in rabbit ocular vasculature are very low frequencyPublication . Delgado, E.; Marques-Neves, C.; Rocha, I.; Sales-Luís, J.; Silva-Carvalho, L.Background/Aims: In a previously described model of isolated rabbit eye, we detected myogenic intrinsic vascular tone of unknown origin in the ophthalmic artery. In order to better understand the origin of these low frequency oscillations, we analyzed their spectral characteristics using fast Fourier. Methods: Hybrid New Zealand rabbits of either sex (n = 24) were used; they were divided into 2 groups according to age. The spectral characteristics of the myogenic behaviour of the rabbit external ophthalmic artery were analyzed using the fast Fourier algorithm. Results: The frequency of the oscillations of the myogenic activity seen in the rabbit external ophthalmic artery varied between 0.033 and 0.066 Hz (mean 0.045 ± 0.012 Hz), all in the region of very low frequency (VLF) oscillations (VLF <0.07 Hz for the rabbit). The frequency of spontaneous oscillations was higher in younger animals. Conclusion: Fast Fourier analysis proved to be an adequate mathematical tool to analyze the myogenic tone oscillations, which were all in the range of VLF in the model we used. These results indicate that myogenic vascular function of ocular blood flow is composed of VLF oscillations, and they provide a new explanation for the origin of VLF in arterial spectra. They also suggest that the ocular local myogenic vascular function observed is more efficient in younger animals
- Dacryops of the lacrimal gland in a dogPublication . Delgado, EsmeraldaA case of congenital lacrimal cyst or dacryops of the lacrimal gland in an 8-month-old Neapolitan Mastiff dog is reported. The dog presented with a swelling dorsolateral to the left globe, which had been present since birth. In addition, hyperplasia and prolapse of the superficial gland of the left nictitating membrane, and bilateral macropalpebral fissure and ‘diamond eye’ conformation were apparent. On manual eversion of the upper eyelid, a subconjunctival mass was visible that was translucent and pink and affected the upper conjunctival fornix. B-mode ultrasonography revealed the presence of an echolucent thin-walled cystic structure measuring 15 by 12 mm and containing an echodense border and a distended tubular fluid-filled structure that extended posteriorly. A viscous and transparent fluid was aspirated from the lesion. Surgery was performed to excise the lesion, reposition the nictitans gland, and correct the morphology of the palpebral fissure. Histopathology confirmed the mass to be a cyst and distended duct of the lacrimal gland. Although tear secretion was compromised, resection of the cyst was curative.
- Biocide and antimicrobial susceptibility of methicillin-resistant staphylococcal isolates from horsesPublication . Couto, Natacha; Belas, Adriana; Tilley, Paula; Couto, Isabel; Gama, Luís T.; Kadlec, Kristina; Schwarz, Stefan; Pomba, ConstançaThe aim of this study was to evaluate the biocide and antimicrobial susceptibility of methicillin-resistant staphylococcal isolates from horses. Fourteen methicillin-resistant staphylococci (MRS) were subjected to an extensive genotype characterization, including SCCmec, dru, spa, PFGE and MLST typing. Antimicrobial susceptibility testing was performed and resistance genes were detected by PCR. Minimum bactericidal concentrations (MBCs) of four biocides [chlorhexidine acetate (CHA), benzalkonium chloride (BAC), triclosan (TCL) and glutaraldehyde (GLA)] were determined following the recommendations of document NF EN 1040. The presence of qac and sh-fabI genes was investigated by PCR. Several antimicrobial resistance patterns and genes were detected. When MRS strains were exposed for a longer period of time, a lower concentration of the biocide was needed to achieve lethality. TCL had the lowest MBC values. All MBC values were lower than the recommended in-use concentrations for veterinary medicine. S. haemolyticus and S. cohnii subsp. cohnii carried plasmid-borne qacA and sh-fabI or qacB and a qacH-like genes, respectively. Biocides appear to be a reliable antiseptic option against MRS, since even in the presence of bacterial efflux mechanisms, the recommended concentration is much higher than the in vitro MBC.
- Intrinsic vasomotricity and adrenergic effects in a model of isolated rabbit eyePublication . Delgado, Esmeralda; Marques-Neves, Carlos; Rocha, Isabel; Sales-Luis, José; Silva-Carvalho, LuísPurpose: We aimed to investigate the responsiveness of the ocular arteries to adrenergic drugs in a model of perfused isolated rabbit eye. Methods: Rabbit external ophthalmic arteries (n = 15) in a head-mounted preparation were cannulated and the retinal and uveal vasculature perfused at a constant flow with warmed tyrode. The three-way polypropylene catheter was further connected to a pressure transducer and intraluminal pressure was taken as a measure of vascular resistance. Effects of intra-arterial injections of phenylephrine (group A, n = 5), prazosin (group B, n = 5) and phentolamine (group C, n = 5) on the recorded pressure were obtained. Student’s paired-t test and one-way analysis of variance were used for statistical analysis (p < 0.05). Results: Intrinsic vasomotricity was observed in all preparations prior to any drug administration. Phenylephrine produced an increase in total vascular resistance. Intrinsic vasomotricity became more evident, showing a lower frequency but higher amplitude of oscillations. Evoked vasomotor responses with phenylephrine (250 lg ⁄ ml) were inhibited by intra-arterial administration of the selective a1-adrenergic antagonist, prazosin (0.5 mg⁄ ml), as well as the non-selective a-adrenergic antagonist phentolamine (6 mg⁄ ml). Conclusions: Rabbit external ophthalmic arteries showed spontaneous contractions under constant perfusion. Phenylephrine elicited a vasoconstrictor response that was inhibited by adrenergic antagonists. In addition, the intrinsic vasomotricity was enhanced by phenylephrine and blocked by adrenergic antagonists. These results show that under in vitro perfusion the territory presents similar responses to adrenergic drugs to those observed in in vivo models and also provides evidence of myogenic autoregulatory properties in the rabbit ophthalmic artery and ⁄ or choroid