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1.
Opt Express ; 32(9): 15955-15966, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859234

RESUMO

A new interactive quantum zero-knowledge protocol for identity authentication implementable in currently available quantum cryptographic devices is proposed and demonstrated. The protocol design involves a verifier and a prover knowing a pre-shared secret, and the acceptance or rejection of the proof is determined by the quantum bit error rate. It has been implemented in modified Quantum Key Distribution devices executing two fundamental cases. In the first case, all players are honest, while in the second case, one of the users is a malicious player. We demonstrate an increase of the quantum bit error rate around 25% in the latter case compared to the case of honesty. The protocol has also been validated for distances from a back-to-back setup to more than 60 km between verifier and prover. The security and robustness of the protocol has been analysed, demonstrating its completeness, soundness and zero-knowledge properties.

2.
Proc Natl Acad Sci U S A ; 118(23)2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34088836

RESUMO

We disclose a peculiar rotational propulsion mechanism of Ray sperms enabled by its unusual heterogeneous dual helixes with a rigid spiral head and a soft tail, named Heterogeneous Dual Helixes (HDH) model for short. Different from the conventional beating propulsion of sperm, the propulsion of Ray sperms is from both the rotational motion of the soft helical tail and the rigid spiral head. Such heterogeneous dual helical propulsion style provides the Ray sperm with high adaptability in viscous solutions along with advantages in linearity, straightness, and bidirectional motion. This HDH model is further corroborated by a miniature swimming robot actuated via a rigid spiral head and a soft tail, which demonstrates similar superiorities over conventional ones in terms of adaptability and efficiency under the same power input. Such findings expand our knowledge on microorganisms' motion, motivate further studies on natural fertilization, and inspire engineering designs.


Assuntos
Espermatozoides/fisiologia , Viscosidade , Humanos , Masculino , Modelos Biológicos , Motilidade dos Espermatozoides/fisiologia , Cauda do Espermatozoide/fisiologia , Espermatozoides/química , Espermatozoides/citologia
3.
Zoo Biol ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965870

RESUMO

Habitat use monitoring is necessary for a comprehensive understanding of the biological and psychological requirements of animals under human care, facilitating improved exhibit designs and promoting animal welfare. Current studies focused on the space use of the exhibit while limited studies examined the pathway use of the zoo-housed animals. This study aimed to investigate the habitat use of An An, the world-oldest male giant panda (Ailuropoda melanoleuca) at Ocean Park Hong Kong using a pathway utilization monitoring method. The result showed uneven utilization of pathways favoring the upper area near his den over the lower area which required longer walking in the hilly exhibit. Moreover, the comparisons of walking directions showed a preference for gentle slopes during uphill movement and a favor for steep slopes during downhill movement. Our study also compared the walking distance between uphill and downhill movements and the results showed that An An walked longer distances heading upward than moving downward due to his choice of pathways. Our results are in line with the findings in the wild population, showing a preference for gentle slopes, especially in uphill movement. Our study demonstrated the value of the pathway monitoring technique. Due to its easy and time-effective use, this technique can be incorporated into the care teams' operation, providing valuable information on daily activity (e.g. accessing the walking ability of the aged animals by investigating the pathway use and walking distance) and habitat use. Consequently, the pathway monitoring technique can help improve exhibit designs promoting welfare.

4.
BMC Vet Res ; 18(1): 417, 2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36435769

RESUMO

BACKGROUND: Vessel collision induces blunt and sharp force traumas to aquatic animals and is a leading anthropogenic impact affecting cetaceans worldwide. Vessel collision is an important threat affecting vulnerable coastal cetaceans such as the Indo-Pacific humpback dolphins (Sousa chinensis) which reside in coastal waters of Hong Kong amongst heavy marine traffic. CASE PRESENTATION: A severely injured subadult S. chinensis was sighted in the waters off southwestern Hong Kong with four gaping incision wounds on its dorsum. It was in poor body condition and seemed unable to use the fluke effectively. The deepest wound located at the caudal peduncle near the base of the fluke and exposed the underlying fractured caudal vertebrae. The dolphin was monitored in the field over three weeks and eventually captured for medical intervention as veterinary assessment indicated progressive and life-threatening deterioration. During rehabilitation, the dolphin demonstrated initial signs of improvement over the first 36 hours as supported by diagnostic tests but then deteriorated rapidly. It was humanely euthanised after three days of rehabilitation. Postmortem investigation was carried out using virtopsy (postmortem computed tomography and magnetic resonance imaging) and conventional necropsy, with special attention to the traumatic musculoskeletal injuries caused by vessel collision and also revealed acute gastrointestinal compromise and respiratory disease that further hampered the rehabilitation. CONCLUSION: In cetaceans, the prognosis for recovery from injuries caused by vessel collision depends on the extent, location, and gravity of the injuries (i.e., superficial, deep, penetrating, blunt vs. sharp, fresh vs. septic), as well as the health status of the individual and its ability to respond to the insult. Injuries extending deep into the vertebral column may lead to delayed death and associated welfare issues. The prognosis of this case was likely poor given the severity and location of the injuries, but the attempted rehabilitation and postmortem investigation provided valuable insights for clinical management if similar cases are encountered in the future. Being able to non-invasively assess and document traumatic injuries and other pathologies, diagnostic imaging is particularly useful in the clinical assessment and postmortem investigation (virtopsy) of cases with vessel-induced injuries.


Assuntos
Golfinhos , Animais , Autopsia/veterinária , Hong Kong
5.
Parasitology ; 147(6): 673-680, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32046802

RESUMO

Here we report on the infection of captive crested geckos Correlophus ciliatus Guichenot (Reptilia: Diplodactylidae), with adults of the ascaridoid nematode, Hexametra angusticaecoides Chabaud & Brygoo, 1960 (Ascarididae). A population of captive crested geckoes became ill and died within a short period of time. Nematodes were recovered from the crested geckoes examined from within the coelomic cavity, penetrating various organs and migrating through subcutaneous tissues, as well as emerging through the geckos' skin. One gecko was treated with levamisole following surgical excision of nematodes from under the skin; this gecko survived. The potential source of the nematode infection in the captive geckoes is discussed. It is most likely that wild-caught Madagascan mossy geckoes, Uroplatus sikorae Boettger (Reptilia: Gekkonidae), introduced the infection to the colony. Molecular sequences of the nematodes are the first produced for the members of this genus. A redescription of the species and its genetic characterization based on the internal transcribed spacer sequence data is provided, suggesting some of the morphological criteria that have been used in the past to distinguish between Hexametra spp. may have been intraspecific morphological variations.


Assuntos
Infecções por Ascaridida/veterinária , Ascaridoidea/fisiologia , Lagartos , Animais , Animais de Zoológico , Infecções por Ascaridida/mortalidade , Infecções por Ascaridida/parasitologia , Feminino , Hong Kong , Masculino
6.
Emerg Infect Dis ; 25(12): 2303-2306, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31742520

RESUMO

We report influenza A(H1N1)pdm09 virus infection in a captive giant panda in Hong Kong. The viral load peaked on day 1 and became undetectable on day 5, and an antibody response developed. Genome analysis showed 99.3%-99.9% nucleotide identity between the virus and influenza A(H1N1)pdm09 virus circulating in Hong Kong.


Assuntos
Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/genética , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/virologia , Ursidae/virologia , Animais , Linhagem Celular , Genoma Viral , Genômica , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Hong Kong/epidemiologia , Masculino , Filogenia , Carga Viral
7.
BMC Vet Res ; 15(1): 4, 2019 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-30606196

RESUMO

BACKGROUND: Nocardiosis is often a multi-systemic disease in humans and other mammals. Nocardiosis in birds is uncommon. Laboratory identification of Nocardia to the species level is difficult by traditional phenotypic methods based on biochemical reactions and hydrolysis tests, and is most accurately performed by sequencing multiple gene targets. CASE PRESENTATION: We report the first case of fatal Nocardia nova infection in a yellow-bibbed lory nestling in an oceanarium diagnosed by multilocus sequencing. Necropsy examination showed effacement of normal sternal musculature with yellowish, firm aberrant material, and diffuse infiltration of the lungs with nodular, tan to yellow foci. Histologically, severe granulomatous inflammation with marked necrosis was observed in the lung, spleen and sternal musculature. Fine, sometimes Gram-positive, 0.5-1 µm wide, branching and beaded filamentous organisms were visible within the lesions. They were acid-fast on Fite-Faraco stain. Tissue samples obtained from the sternum, liver, right lung and right kidney recovered Nocardia species. Sequencing of four gene loci and phylogenetic analysis of concatenated (gyrB-16S-secA1-hsp65) sequences revealed that the isolate was N. nova. CONCLUSIONS: We report the first case of N. nova infection in yellow-bibbed lorry (Lorius chlorocercus). The present case is the first one of which the species identity of the isolate was determined by multilocus sequencing. Molecular diagnosis is important for identifying the Nocardia to species level and understanding the epidemiology of nocardiosis in birds.


Assuntos
Doenças das Aves/microbiologia , Nocardiose/veterinária , Nocardia/genética , Papagaios/microbiologia , Animais , Animais de Zoológico/microbiologia , Doenças das Aves/patologia , Evolução Fatal , Hong Kong , Pulmão/microbiologia , Pulmão/patologia , Tipagem de Sequências Multilocus/veterinária , Nocardiose/microbiologia , Nocardiose/patologia , Filogenia
8.
J Gen Virol ; 99(6): 777-782, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29722646

RESUMO

In this study, two novel noroviruses (NoVs) were discovered from faecal samples from California sea lions from an oceanarium in Hong Kong, and named California sea lion NoV 1 (Csl/NoV1) and California sea lion NoV 2 (Csl/NoV2). Whole-genome sequencing showed that the genome organization and amino acid motifs of both Csl/NoV1 and Csl/NoV2 were typical of those of other NoVs in their open reading frames (ORFs). Csl/NoV1 possessed only 52.6-52.8 % amino acid identity in VP1 to the closest matches in genogroup GII. Therefore, Csl/NoV1 should constitute a novel genogroup of NoV. Shifting of the phylogenetic position of Csl/NoV1 in the RdRp, VP1 and VP2 trees was observed, which may have been due to recombination events and/or biased mutations. Csl/NoV2 possessed 55.4-56.2 % amino acid identity in VP1 to its closest relatives in genogroup GVI, which means that it represents a new genotype in genogroup GVI. Further studies will reveal what diseases these NoVs can cause in marine mammals.


Assuntos
Infecções por Caliciviridae/veterinária , Genoma Viral , Norovirus/classificação , Leões-Marinhos/virologia , Animais , California , Fezes/virologia , Variação Genética , Genótipo , Norovirus/genética , Norovirus/isolamento & purificação , Fases de Leitura Aberta/genética , Filogenia , Análise de Sequência de DNA , Sequenciamento Completo do Genoma
10.
J Zoo Wildl Med ; 49(2): 470-474, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29900778

RESUMO

Two adult sibling red-handed tamarins ( Saguinus midas) presented with weight loss and multifocal skin masses. A skin biopsy revealed pyogranulomatous dermatitis with intrafollicular Demodex sp. mites. Subsequent skin scrapes confirmed the presence of live mites within lesions. Initial treatment with topical and oral ivermectin was unsuccessful, and lesions continued to progress. A single dose of fluralaner (Bravecto®, Merck Animal Health, Kenilworth, New Jersey, 07033, USA; 28.125 mg po) was administered to each animal approximately 5 mo after initial presentation. Lesions resolved over the next 3 mo, and all follow-up skin scrapes were negative for both animals. No adverse effects were noted. A single oral administration of fluralaner at 30-35 mg/kg appears adequate and safe for the treatment of generalized demodicosis in red-handed tamarins.


Assuntos
Acaricidas/uso terapêutico , Isoxazóis/uso terapêutico , Infestações por Ácaros/veterinária , Ácaros/efeitos dos fármacos , Doenças dos Macacos/tratamento farmacológico , Saguinus , Administração Oral , Animais , Animais de Zoológico , Feminino , Masculino , Infestações por Ácaros/tratamento farmacológico
11.
BMC Vet Res ; 12: 77, 2016 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-27170186

RESUMO

BACKGROUND: This study was aimed at evaluating the clinical protection, the level of Porcine circovirus type 2 (PCV2) viremia and the immune response (antibodies and IFN-γ secreting cells (SC)) in piglets derived from PCV2 vaccinated sows and themselves vaccinated against PCV2 at different age, namely at 4, 6 and 8 weeks. The cohort study has been carried out over three subsequent production cycles (replicates). At the start/enrolment, 46 gilts were considered at first mating, bled and vaccinated. At the first, second and third farrowing, dams were bled and re-vaccinated at the subsequent mating after weaning piglets. Overall 400 piglets at each farrowing (first, second and third) were randomly allocated in three different groups (100 piglets/group) based on the timing of vaccination (4, 6 or 8 weeks of age). A fourth group was kept non-vaccinated (controls). Piglets were vaccinated intramuscularly with one dose (2 mL) of a commercial PCV2a-based subunit vaccine (Porcilis® PCV). Twenty animals per group were bled at weaning and from vaccination to slaughter every 4 weeks for the detection of PCV2 viremia, humoral and cell-mediated immune responses. Clinical signs and individual treatments (morbidity), mortality, and body weight of all piglets were recorded. RESULTS: All vaccination schemes (4, 6 and 8 weeks of age) were able to induce an antibody response and IFN-γ SC. The highest clinical and virological protection sustained by immune reactivity was observed in pigs vaccinated at 6 weeks of age. Overall, repeated PCV2 vaccination in sows at mating and the subsequent higher levels of maternally derived antibodies did not significantly interfere with the induction of both humoral and cell-mediated immunity in their piglets after vaccination. CONCLUSIONS: The combination of vaccination in sows at mating and in piglets at 6 weeks of age was more effective for controlling PCV2 natural infection, than other vaccination schemas, thus sustaining that some interference of MDA with the induction of an efficient immune response could be considered. In conclusion, optimal vaccination strategy needs to balance the levels of passive immunity, the management practices and timing of infection.


Assuntos
Infecções por Circoviridae/veterinária , Circovirus/imunologia , Imunidade Materno-Adquirida , Doenças dos Suínos/imunologia , Vacinas Virais/imunologia , Envelhecimento/imunologia , Animais , Anticorpos Antivirais/análise , Anticorpos Antivirais/imunologia , Peso Corporal , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/prevenção & controle , Método Duplo-Cego , Feminino , Imunidade Celular , Interferon gama/metabolismo , Masculino , Suínos , Doenças dos Suínos/prevenção & controle , Doenças dos Suínos/virologia
12.
J Zoo Wildl Med ; 47(1): 325-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27010295

RESUMO

In 2002 a 23-yr-old female giant panda (Ailuropoda melanoleuca) presented with left hind limb lameness presumably due to osteoarthritis. For the next five years, arthritic episodes were managed with the nonsteroidal anti-inflammatory drug (NSAID) carprofen at 2 mg/kg p.o. s.i.d., then reduced to 1 mg/kg p.o. s.i.d. and withdrawn. Radiographs revealed osteoarthritis in various joints and lumbar spondylosis. In 2007 glucosamine and chondroitin at 1.65 g p.o. b.i.d. and a polyunsaturated fatty acid at 1 capsule p.o. s.i.d. By 2008, arthritic episodes were becoming more difficult to successfully manage and higher doses and longer durations of treatment with carprofen were needed (2 mg/kg p.o. b.i.d.) and by August 2009 episodic treatment was no longer successful so the carprofen was continued indefinitely at 1 mg/kg p.o. s.i.d. In November 2009 carprofen was increased to 2 mg/kg p.o. b.i.d. An NMDA antagonist amantadine sulphate was trialed and after 10 days at 200 mg p.o. s.i.d. the clinical signs resolved. Since then it has been maintained on carprofen at 1 mg/kg p.o. b.i.d., amantadine sulphate 200 mg p.o. s.i.d. and the neutraceuticals as above with no further relapses of arthritic pain.


Assuntos
Amantadina/uso terapêutico , Analgésicos não Narcóticos/uso terapêutico , Osteoartrite/veterinária , Ursidae , Amantadina/administração & dosagem , Analgésicos não Narcóticos/administração & dosagem , Animais , Animais de Zoológico , Anti-Inflamatórios não Esteroides/uso terapêutico , Carbazóis/uso terapêutico , Feminino , Osteoartrite/tratamento farmacológico
13.
J Virol ; 88(2): 1318-31, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24227844

RESUMO

While gammacoronaviruses mainly comprise infectious bronchitis virus (IBV) and its closely related bird coronaviruses (CoVs), the only mammalian gammacoronavirus was discovered from a white beluga whale (beluga whale CoV [BWCoV] SW1) in 2008. In this study, we discovered a novel gammacoronavirus from fecal samples from three Indo-Pacific bottlenose dolphins (Tursiops aduncus), which we named bottlenose dolphin CoV (BdCoV) HKU22. All the three BdCoV HKU22-positive samples were collected on the same date, suggesting a cluster of infection, with viral loads of 1 × 10(3) to 1 × 10(5) copies per ml. Clearance of virus was associated with a specific antibody response against the nucleocapsid of BdCoV HKU22. Complete genome sequencing and comparative genome analysis showed that BdCoV HKU22 and BWCoV SW1 have similar genome characteristics and structures. Their genome size is about 32,000 nucleotides, the largest among all CoVs, as a result of multiple unique open reading frames (NS5a, NS5b, NS5c, NS6, NS7, NS8, NS9, and NS10) between their membrane (M) and nucleocapsid (N) protein genes. Although comparative genome analysis showed that BdCoV HKU22 and BWCoV SW1 should belong to the same species, a major difference was observed in the proteins encoded by their spike (S) genes, which showed only 74.3 to 74.7% amino acid identities. The high ratios of the number of synonymous substitutions per synonymous site (Ks) to the number of nonsynonymous substitutions per nonsynonymous site (Ka) in multiple regions of the genome, especially the S gene (Ka/Ks ratio, 2.5), indicated that BdCoV HKU22 may be evolving rapidly, supporting a recent transmission event to the bottlenose dolphins. We propose a distinct species, Cetacean coronavirus, in Gammacoronavirus, to include BdCoV HKU22 and BWCoV SW1, whereas IBV and its closely related bird CoVs represent another species, Avian coronavirus, in Gammacoronavirus.


Assuntos
Golfinho Nariz-de-Garrafa/virologia , Infecções por Coronaviridae/veterinária , Coronaviridae/classificação , Coronaviridae/isolamento & purificação , Animais , Sequência de Bases , Coronaviridae/genética , Infecções por Coronaviridae/virologia , Genoma Viral , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia
14.
J Clin Microbiol ; 52(10): 3614-23, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25078906

RESUMO

Beginning in July 2011, 31 green anaconda (Eunectes murinus) juveniles from an oceanarium in Hong Kong died over a 12-month period. Necropsy revealed at least two of the following features in 23 necropsies: dermatitis, severe pan-nephritis, and/or severe systemic multiorgan necrotizing inflammation. Histopathological examination revealed severe necrotizing inflammation in various organs, most prominently the kidneys. Electron microscopic examination of primary tissues revealed intralesional accumulations of viral nucleocapsids with diameters of 10 to 14 nm, typical of paramyxoviruses. Reverse transcription (RT)-PCR results were positive for paramyxovirus (viral loads of 2.33 × 10(4) to 1.05 × 10(8) copies/mg tissue) in specimens from anaconda juveniles that died but negative in specimens from the two anaconda juveniles and anaconda mother that survived. None of the other snakes in the park was moribund, and RT-PCR results for surveillance samples collected from other snakes were negative. The virus was isolated from BHK21 cells, causing cytopathic effects with syncytial formation. The virus could also replicate in 25 of 27 cell lines of various origins, in line with its capability for infecting various organs. Electron microscopy with cell culture material revealed enveloped virus with the typical "herringbone" appearance of helical nucleocapsids in paramyxoviruses. Complete genome sequencing of five isolates confirmed that the infections originated from the same clone. Comparative genomic and phylogenetic analyses and mRNA editing experiments revealed a novel paramyxovirus in the genus Ferlavirus, named anaconda paramyxovirus, with a typical Ferlavirus genomic organization of 3'-N-U-P/V/I-M-F-HN-L-5'. Epidemiological and genomic analyses suggested that the anaconda juveniles acquired the virus perinatally from the anaconda mother rather than from other reptiles in the park, with subsequent interanaconda juvenile transmission.


Assuntos
Boidae/virologia , Infecções por Paramyxoviridae/veterinária , Paramyxovirinae/classificação , Paramyxovirinae/isolamento & purificação , Estruturas Animais/patologia , Estruturas Animais/virologia , Animais , Animais de Zoológico , Linhagem Celular , Análise por Conglomerados , Hong Kong , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Infecções por Paramyxoviridae/patologia , Infecções por Paramyxoviridae/virologia , Paramyxovirinae/genética , Filogenia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Homologia de Sequência , Carga Viral , Vírion/ultraestrutura , Cultura de Vírus
15.
Mol Ecol ; 23(8): 2072-92, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24629132

RESUMO

The dynamic geological and climatological history of Southeast Asia has spawned a complex array of ecosystems and 12 of the 37 known cat species, making it the most felid-rich region in the world. To examine the evolutionary histories of these poorly studied fauna, we compared phylogeography of six species (leopard cat Prionailurus bengalensis, fishing cat P. viverrinus, Asiatic golden cat Pardofelis temminckii, marbled cat P. marmorata, tiger Panthera tigris and leopard P. pardus) by sequencing over 5 kb of DNA each from 445 specimens at multiple loci of mtDNA, Y and X chromosomes. All species except the leopard displayed significant phylogenetic partitions between Indochina and Sundaland, with the central Thai-Malay Peninsula serving as the biogeographic boundary. Concordant mtDNA and nuclear DNA genealogies revealed deep Indochinese-Sundaic divergences around 2 MYA in both P. bengalensis and P. marmorata comparable to previously described interspecific distances within Felidae. The divergence coincided with serial sea level rises during the late Pliocene and early Pleistocene, and was probably reinforced by repeated isolation events associated with environmental changes throughout the Pleistocene. Indochinese-Sundaic differentiations within P. tigris and P. temminckii were more recent at 72-108 and 250-1570 kya, respectively. Overall, these results illuminate unexpected, deep vicariance events in Southeast Asian felids and provide compelling evidence of species-level distinction between the Indochinese and Sundaic populations in the leopard cat and marbled cat. Broader sampling and further molecular and morphometric analyses of these species will be instrumental in defining conservation units and effectively preserving Southeast Asian biodiversity.


Assuntos
Evolução Biológica , Felidae/classificação , Filogenia , Animais , Sudeste Asiático , DNA Mitocondrial/genética , Felidae/genética , Marcadores Genéticos , Haplótipos , Dados de Sequência Molecular , Filogeografia , Análise de Sequência de DNA , Cromossomo X/genética , Cromossomo Y/genética
16.
Vet Res ; 45: 44, 2014 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-24735253

RESUMO

Porcine circovirus type 2 (PCV2) vaccination represents an important measure to cope with PCV2 infection; however, data regarding the modulation of the immune cell compartment are still limited, especially under field conditions. This study is aimed at investigating the features of the cellular immune response in conventional piglets induced by vaccination using a capsid (Cap) protein-based PCV2 vaccine compared to unvaccinated animals when exposed to PCV2 natural infection. Immune reactivity was evaluated by quantifying peripheral cell subsets involved in the anti-viral response and characterizing the interferon-gamma (IFN-γ) secreting cell (SC) responsiveness both in vivo and upon in vitro whole PCV2 recall. The vaccination triggered an early and intense IFN-γ secreting cell response and induced the activation of peripheral lymphocytes. The early increase of IFN-γ SC frequencies resulted in a remarkable and transient tendency to increased IFN-γ productivity in vaccinated pigs. In vaccinated animals, soon before the onset of infection occurred 15-16 weeks post-vaccination, the recalled PCV2-specific immune response was characterized by moderate PCV2-specific IFN-γ secreting cell frequencies and augmented productivity together with reactive CD4+CD8+ memory T cells. Conversely, upon infection, unvaccinated animals showed very high frequencies of IFN-γ secreting cells and a tendency to lower productivity, which paralleled with effector CD4-CD8+ cytotoxic cell responsiveness. The study shows that PCV2 vaccination induces a long-lasting immunity sustained by memory T cells and IFN-γ secreting cells that potentially played a role in preventing the onset of infection; the extent and duration of this reactivity can be an important feature for evaluating the protective immunity induced by vaccination.


Assuntos
Infecções por Circoviridae/veterinária , Circovirus/imunologia , Imunidade Celular , Doenças dos Suínos/imunologia , Animais , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/virologia , ELISPOT/veterinária , Citometria de Fluxo/veterinária , Interferon gama/biossíntese , Mitógenos/imunologia , Reação em Cadeia da Polimerase/veterinária , Suínos , Doenças dos Suínos/virologia , Linfócitos T/imunologia , Vacinas Virais/administração & dosagem
17.
Res Vet Sci ; 171: 105231, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38513460

RESUMO

Intestinal disorders can affect pigs of any age, especially when animals are young and more susceptible to infections and environmental stressors. For instance, pathogenic E. coli can alter intestinal functions, thus leading to altered nutrient adsorption by interacting with local cells through lipopolysaccharide (LPS). Among several compounds studied to counteract the negative effects on the intestine, short-chain fatty acids (SCFA) were demonstrated to exert beneficial effects on gut epithelial cells and resident immune cells. In this study, acetate and propionate were tested for their beneficial effects in a co-culture model of IPEC-J2 and porcine PBMC pre-stimulated with LPS from E. coli 0111:B4 aimed at mimicking the interaction between intestinal cells and immune cells in an inflammatory/activated status. IPEC-J2 viability was partially reduced when co-cultured with activated PBMC and nitric oxide concentration increased. IPEC-J2 up-regulated innate and inflammatory markers, namely BD-1, TLR-4, IL-8, TNF-α, NF-κB, and TGF-ß. Acetate and propionate positively modulated the inflammatory condition by sustaining cell viability, reducing the oxidative stress, and down-regulating the expression of inflammatory mediators. TNF-α expression and secretion showed an opposite effect in IPEC-J2 depending on the extent of LPS stimulation of PBMC and TGF-ß modulation. Therefore, SCFA proved to mediate a differential effect depending on the degree and duration of inflammation. The expression of the tight junction proteins (TJp) claudin-4 and zonula occludens-1 was up-regulated by LPS while SCFA influenced TJp with a different kinetics depending on PBMC stimulation. The co-culture model of IPEC-J2 and LPS-activated PBMC proved to be feasible to address the modulation of markers related to anti-bacterial immunity and inflammation, and intestinal epithelial barrier integrity, which are involved in the in vivo responsiveness and plasticity to infections.


Assuntos
Escherichia coli , Doenças dos Suínos , Animais , Suínos , Escherichia coli/metabolismo , Lipopolissacarídeos/toxicidade , Fator de Necrose Tumoral alfa/metabolismo , Propionatos , Leucócitos Mononucleares/metabolismo , Linhagem Celular , Células Epiteliais/metabolismo , Ácidos Graxos Voláteis , Acetatos , Fator de Crescimento Transformador beta , Inflamação/veterinária , Mucosa Intestinal/metabolismo
19.
J Virol ; 86(11): 6377-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22570247

RESUMO

We discovered a novel otarine picobirnavirus in fecal samples of California sea lions. Its genome contains a large segment with two open reading frames (ORFs), ORF1 encoding a putative protein of 163 amino acids with unknown function and ORF2 encoding capsid protein, and a small segment with one ORF encoding RNA-dependent RNA polymerase.


Assuntos
Genoma Viral , Picobirnavirus/genética , Infecções por Vírus de RNA/veterinária , RNA Viral/genética , Leões-Marinhos/virologia , Análise de Sequência de DNA , Animais , Fezes/virologia , Dados de Sequência Molecular , Fases de Leitura Aberta , Picobirnavirus/isolamento & purificação , Infecções por Vírus de RNA/virologia , Proteínas Virais/genética
20.
Opt Express ; 21(21): 25174-83, 2013 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-24150359

RESUMO

The complexity and the power consumption of digital signal processing are crucial issues in optical transmission systems based on mode division multiplexing and coherent multiple-input multiple-output (MIMO) processing at the receiver. In this paper the inherent characteristic of spatial separation between fiber modes is exploited, getting a MIMO system where joint demultiplexing and detection is based on spatially separated photodetectors. After photodetection, one has a MIMO system with nonlinear crosstalk between modes. The paper shows that the nonlinear crosstalk can be dealt with by a low-complexity and non-adaptive detection scheme, at least in the cases presented in the paper.

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