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2.
Immunogenetics ; 72(1-2): 101-108, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31797007

RESUMO

The domestic ferret, Mustela putorius furo, is an important mammalian animal model to study human respiratory infection. However, insufficient genomic annotation hampers detailed studies of ferret T cell responses. In this study, we analyzed the published T cell receptor beta (TRB) locus and performed high-throughput sequencing (HTS) of peripheral blood of four healthy adult ferrets to identify expressed V, D, J, and C genes. The HTS data is used as a guide to manually curate the expressed V, D, J, and C genes. The ferret locus appears to be most similar to that of the dog. Like other mammalian TRB loci, the ferret TRB locus contains a library of variable genes located upstream of two D-J-C gene clusters, followed by a (in the ferret non-functional) V gene with an inverted transcriptional orientation. All TRB genes (expressed or not) reported here have been approved by the IMGT/WHO-IUIS nomenclature committee.


Assuntos
Regulação da Expressão Gênica , Rearranjo Gênico da Cadeia beta dos Receptores de Antígenos dos Linfócitos T/genética , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Animais , Furões , Sequenciamento de Nucleotídeos em Larga Escala
3.
Vet Clin North Am Exot Anim Pract ; 23(1): 169-193, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31759446

RESUMO

Diseases of the urinary tract are reviewed, covering infectious (bacterial, viral, parasitic), degenerative, congenital, metabolic, nutritional, neoplastic, obstructive, and toxic causes. Some clinical presentations and diagnostic procedures are described for ferrets, rabbits, guinea pigs, hamsters, mice, rats, chinchillas, hedgehogs, and sugar gliders, as well as therapies.


Assuntos
Mamíferos , Doenças Urológicas/veterinária , Animais , Chinchila , Cricetinae , Furões , Cobaias , Ouriços-Cacheiros , Marsupiais , Camundongos , Animais de Estimação , Coelhos , Ratos , Doenças Urológicas/diagnóstico , Doenças Urológicas/patologia , Doenças Urológicas/terapia
4.
Vet Clin North Am Exot Anim Pract ; 23(1): 195-214, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31759447

RESUMO

Radiographs can be used to easily visualize common types of urinary calculi in all parts of the urinary tract. Positive-contrast excretory urography and cystourethrography are sensitive to diseases within the ureters and urethra, most commonly obstruction. Ultrasound is widely available and noninvasive and can be used to evaluate renal architecture, ureteral dilation, urinary bladder wall disease, and urolithiasis. Computed tomography is increasing in availability and provides a large amount of cross-sectional information quickly and noninvasively. Multiple imaging modalities can be used to estimate or quantify glomerular filtration rate.


Assuntos
Mamíferos , Animais , Furões , Taxa de Filtração Glomerular/veterinária , Rim/diagnóstico por imagem , Animais de Estimação , Coelhos , Tomografia Computadorizada por Raios X/veterinária , Ultrassonografia/veterinária , Sistema Urinário/diagnóstico por imagem , Urografia/veterinária
5.
J Endod ; 46(2): 209-215, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31859008

RESUMO

INTRODUCTION: SynOss Putty (Collagen Matrix, Oakland, NJ) has shown the formation of mineralized tissues when used as a scaffold in regenerative endodontic treatment (RET) in immature human teeth. The aim of this study was to compare the outcome of RET in immature ferret teeth using 2 scaffolds: a blood clot and SynOss Putty. METHODS: Thirty-two immature canine teeth in 8 ferrets (95-105 days old) were divided into 4 groups: group 1, no treatment (positive control, n = 8); group 2, full pulpectomy with no further treatment (negative control, n = 8); group 3, revascularization using a blood clot (n = 8); and group 4, revascularization using a SynOss Putty scaffold (n = 8). After 3 months, the animals were euthanized, and the newly formed tissues were examined histologically. The data were statistically analyzed using chi-square and Fisher exact tests. RESULTS: Normal pulps were found in group 1. No pulp tissue was found in teeth in group 2. In group 3, the pulp tissue and the odontoblastic layer were absent, and the root canal spaces were filled with a hard tissue characterized as bonelike and cementumlike tissues. All teeth except 1 in group 4 showed no hard tissue formation and intracanal/periapical inflammation. SynOss Putty was significantly associated with a lack of tissue formation and intracanal/periapical inflammation (P < .05). CONCLUSIONS: Intracanal hard tissue formation was observed in immature teeth after RET using a blood clot. No tissue regeneration was found in the majority of samples using SynOss Putty as a scaffold.


Assuntos
Necrose da Polpa Dentária , Furões , Endodontia Regenerativa , Trombose , Tecidos Suporte , Animais , Polpa Dentária , Humanos , Endodontia Regenerativa/métodos
6.
Parasit Vectors ; 12(1): 465, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31590678

RESUMO

BACKGROUND: Anaplasma phagocytophilum is an obligate parasitic intracellular bacterium. It is the causative agent of granulocytic anaplasmosis, with effects on human and animal health. In Europe, the pathogen is mainly transmitted among a wide range of vertebrate hosts by blood-sucking arthropods. The aim of this study was to determine the presence of A. phagocytophilum in wild carnivores, viz raccoon dogs (Nyctereutes procyonoides), badgers (Meles meles), foxes (Vulpes vulpes), martens (Martes sp.) and European polecats (Mustela putorius), using molecular methods. METHODS: In the present study, 174 spleen samples were collected from adult, wild carnivores hunted in the years 2013-2016. A short fragment (383 bp) of the 16S ribosomal RNA gene partial sequence was used as a marker to identify A. phagocytophilum in spleen samples collected from carnivores using nested PCR. RESULTS: The prevalence of A. phagocytophilum in wild carnivores was 31.61% (55/174). Seven sequences of A. phagocytophilum were generated from two raccoon dogs, two badgers, one marten, one red fox and one European polecat. Six identical nucleotide sequences were obtained from one raccoon dog, two badgers, one marten, one red fox and one European polecat (A. phagocytophilum sequences 1: MH328205-MH328209, MH328211), and these were identical to many A. phagocytophilum sequences in the GenBank database (100% similarity). The second sequence (A. phagocytophilum sequence 2: MH328210) obtained from the raccoon dog shared 99.74% identity with A. phagocytophilum sequence 1. CONCLUSIONS: To our knowledge, this is the first study to use molecular methods to determine the presence of A. phagocytophilum in wild carnivores, viz raccoon dog, badger, marten and European polecat, in Poland. The detected A. phagocytophilum sequences (1 and 2) were closely related with those of A. phagocytophilum occurring in a wide range of wild and domestic animals and vectors.


Assuntos
Anaplasma phagocytophilum/isolamento & purificação , Ehrlichiose/veterinária , Furões , Raposas , Mustelidae , Anaplasma phagocytophilum/genética , Animais , Animais Selvagens , DNA Bacteriano/isolamento & purificação , Reservatórios de Doenças/classificação , Reservatórios de Doenças/microbiologia , Ehrlichiose/epidemiologia , Ehrlichiose/microbiologia , Eletroforese em Gel de Ágar/veterinária , Feminino , Masculino , Polônia/epidemiologia , Reação em Cadeia da Polimerase/veterinária , Prevalência , RNA Ribossômico 16S/genética , Baço/microbiologia
7.
PLoS Comput Biol ; 15(10): e1007430, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31626624

RESUMO

Perception of vocalizations and other behaviorally relevant sounds requires integrating acoustic information over hundreds of milliseconds. Sound-evoked activity in auditory cortex typically has much shorter latency, but the acoustic context, i.e., sound history, can modulate sound evoked activity over longer periods. Contextual effects are attributed to modulatory phenomena, such as stimulus-specific adaption and contrast gain control. However, an encoding model that links context to natural sound processing has yet to be established. We tested whether a model in which spectrally tuned inputs undergo adaptation mimicking short-term synaptic plasticity (STP) can account for contextual effects during natural sound processing. Single-unit activity was recorded from primary auditory cortex of awake ferrets during presentation of noise with natural temporal dynamics and fully natural sounds. Encoding properties were characterized by a standard linear-nonlinear spectro-temporal receptive field (LN) model and variants that incorporated STP-like adaptation. In the adapting models, STP was applied either globally across all input spectral channels or locally to subsets of channels. For most neurons, models incorporating local STP predicted neural activity as well or better than LN and global STP models. The strength of nonlinear adaptation varied across neurons. Within neurons, adaptation was generally stronger for spectral channels with excitatory than inhibitory gain. Neurons showing improved STP model performance also tended to undergo stimulus-specific adaptation, suggesting a common mechanism for these phenomena. When STP models were compared between passive and active behavior conditions, response gain often changed, but average STP parameters were stable. Thus, spectrally and temporally heterogeneous adaptation, subserved by a mechanism with STP-like dynamics, may support representation of the complex spectro-temporal patterns that comprise natural sounds across wide-ranging sensory contexts.


Assuntos
Córtex Auditivo/fisiologia , Percepção Auditiva/fisiologia , Estimulação Acústica , Potenciais de Ação/fisiologia , Adaptação Fisiológica/fisiologia , Animais , Feminino , Furões , Masculino , Modelos Neurológicos , Modelos de Interação Espacial , Plasticidade Neuronal , Neurônios/fisiologia , Ruído , Som
8.
J Vet Diagn Invest ; 31(6): 828-835, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31551015

RESUMO

Cryptococcosis, caused by the Cryptococcus gattii and C. neoformans species complexes, is an environmentally acquired mycosis affecting a broad range of host species. Among 9 communally housed ferrets, a 5-y-old castrated male ferret domiciled in an outdoor enclosure in Sydney, Australia was diagnosed with sinonasal cryptococcosis. Clinical signs resolved during 18 mo of itraconazole therapy, but the ferret was eventually euthanized because of splenic hemangiosarcoma. At postmortem, microscopic foci of persistent cryptococcosis were detected. The diagnosis raised concerns that the owners and other ferrets were exposed to a common environmental source of infection, thus prompting an investigation. Soil samples, swabs of a hollow eucalypt log (used for behavioral enrichment), and nasal swabs from 8 asymptomatic ferrets were collected. Nasal exudate (obtained at diagnosis) and tissues (collected at postmortem) were available from the clinical case. Bird seed agar culture resulted in a heavy growth of Cryptococcus spp. from one environmental site (the log), one nasal swab, and nasal exudate and tissues from the clinical case. All other samples were culture-negative. Sub-cultured isolates from the log were a mixture of C. gattii molecular type VGI and C. neoformans molecular type VNI. Ferret isolates were a similar mixture of C. gattii VGI (all disease isolates) and C. neoformans VNI (nasal-colonizing isolate). Multilocus sequence typing further revealed the ferret isolates as identical to environmental isolates collected from the log, confirming the log as the source of clinical disease and nasal colonization. The log was removed to prevent further exposure to a high environmental load of Cryptococcus spp.


Assuntos
Antifúngicos/uso terapêutico , Criptococose/veterinária , Furões , Itraconazol/uso terapêutico , Doenças dos Seios Paranasais/veterinária , Animais , Criptococose/diagnóstico , Criptococose/tratamento farmacológico , Cryptococcus gattii/isolamento & purificação , Cryptococcus neoformans/isolamento & purificação , Masculino , New South Wales , Doenças dos Seios Paranasais/diagnóstico , Doenças dos Seios Paranasais/tratamento farmacológico
9.
Emerg Microbes Infect ; 8(1): 1324-1336, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31503518

RESUMO

Avian influenza A viruses (AIV) of the H7 subtype continue to evolve posing a pandemic threat. However, molecular markers of H7N7 AIV pathogenicity and transmission in mammals remain poorly understood. In this study, we performed a systematic in vitro and in vivo analysis by comparing an H7N7 highly pathogenic AIV and its ferret adapted variant. Passaging an H7N7 AIV in ferrets led to six mutations in genes encoding the viral polymerase complex and the viral surface proteins. Here, we show that mutations in the H7 hemagglutinin gene cause increased pathogenicity in mice. Contact transmission between guinea pigs required additional mutations in the gene encoding the polymerase subunit PB1. Thus, particular vigilance is required with respect to HA and PB1 mutations as predictive molecular markers to assess the pandemic risk posed by emerging H7 avian influenza viruses.


Assuntos
Transmissão de Doença Infecciosa , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H7N7/patogenicidade , Proteínas Mutantes/genética , Infecções por Orthomyxoviridae/transmissão , Infecções por Orthomyxoviridae/virologia , Proteínas Virais/genética , Animais , Modelos Animais de Doenças , Furões , Cobaias , Vírus da Influenza A Subtipo H7N7/genética , Infecções por Orthomyxoviridae/patologia , Inoculações Seriadas , Fatores de Virulência/genética
10.
Emerg Microbes Infect ; 8(1): 1280-1290, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31495283

RESUMO

The H3N2 influenza viruses became widespread in humans during the 1968 H3N2 pandemic and have been a major cause of influenza epidemics ever since. Different lineages of H3N2 influenza viruses are also commonly found in animals. If a different lineage of H3N2 virus jumps to humans, a human influenza pandemic could occur with devastating consequences. Here, we studied the genetics, receptor-binding properties, and replication and transmission in mammals of 15 H3N2 avian influenza viruses detected in live poultry markets in China. We found that the H3N2 avian influenza viruses are complicated reassortants with distinct replication phenotypes in mice. Five viruses replicated efficiently in mice and bound to both human-type and avian-type receptors. These viruses transmitted efficiently to direct-contact guinea pigs, and three of them also transmitted among guinea pigs and ferrets via respiratory droplets. Moreover, ferret antiserum induced by human H3N2 viruses did not react with any of the H3N2 avian influenza viruses. Our study demonstrates that the H3N2 avian influenza viruses pose a clear threat to human health and emphasizes the need for continued surveillance and evaluation of the H3N2 influenza viruses circulating in nature.


Assuntos
Transmissão de Doença Infecciosa , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/fisiologia , Influenza Aviária/virologia , Aves Domésticas/virologia , Ligação Viral , Animais , China , Modelos Animais de Doenças , Furões , Cobaias , Humanos , Vírus da Influenza A Subtipo H3N2/genética , Camundongos Endogâmicos BALB C , Vírus Reordenados/genética , Vírus Reordenados/isolamento & purificação , Vírus Reordenados/fisiologia , Receptores Virais/metabolismo , Doenças dos Roedores/virologia , Replicação Viral
11.
Vet Clin North Am Exot Anim Pract ; 22(3): 521-538, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31395329

RESUMO

Medical devices are defined as implantable if they are intended to remain in the body after the procedure. In veterinary medicine, use of such devices is marginal but may find some indications. Use in exotic pet medicine is even more challenging due to size restriction and the limited data available. This review focuses on the esophageal and tracheal stent in the case of stricture, ureteral stent and subcutaneous ureteral bypass in the case of ureteral obstruction, permanent urinary diversion in the case of bladder atony, and pacemaker in the case of severe arrythmias. Comparative aspects are developed.


Assuntos
Obstrução das Vias Respiratórias/veterinária , Animais Exóticos , Materiais Biocompatíveis/classificação , Estenose Esofágica/veterinária , Marca-Passo Artificial/veterinária , Obstrução Ureteral/veterinária , Obstrução das Vias Respiratórias/terapia , Animais , Gatos , Cistotomia/instrumentação , Cistotomia/veterinária , Cães , Estenose Esofágica/terapia , Feminino , Furões , Humanos , Masculino , Coelhos , Stents , Obstrução Ureteral/terapia , Derivação Urinária
12.
Nat Commun ; 10(1): 3836, 2019 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-31444366

RESUMO

Although the incidence of severe fever with thrombocytopenia syndrome virus (SFTSV) infection has increased from its discovery with a mortality rate of 10-20%, no effective vaccines are currently available. Here we describe the development of a SFTSV DNA vaccine, its immunogenicity, and its protective efficacy. Vaccine candidates induce both a neutralizing antibody response and multifunctional SFTSV-specific T cell response in mice and ferrets. When the vaccine efficacy is investigated in aged-ferrets that recapitulate fatal clinical symptoms, vaccinated ferrets are completely protected from lethal SFTSV challenge without developing any clinical signs. A serum transfer study reveals that anti-envelope antibodies play an important role in protective immunity. Our results suggest that Gn/Gc may be the most effective antigens for inducing protective immunity and non-envelope-specific T cell responses also can contribute to protection against SFTSV infection. This study provides important insights into the development of an effective vaccine, as well as corresponding immune parameters, to control SFTSV infection.


Assuntos
Imunogenicidade da Vacina , Febre por Flebótomos/prevenção & controle , Phlebovirus/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Modelos Animais de Doenças , Feminino , Furões , Humanos , Camundongos , Febre por Flebótomos/imunologia , Febre por Flebótomos/virologia , Phlebovirus/genética , Resultado do Tratamento , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologia , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/imunologia , Vacinas Virais/administração & dosagem
13.
Elife ; 82019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-31452511

RESUMO

A longstanding question is how influenza virus evolves to escape human immunity, which is polyclonal and can target many distinct epitopes. Here, we map how all amino-acid mutations to influenza's major surface protein affect viral neutralization by polyclonal human sera. The serum of some individuals is so focused that it selects single mutations that reduce viral neutralization by over an order of magnitude. However, different viral mutations escape the sera of different individuals. This individual-to-individual variation in viral escape mutations is not present among ferrets that have been infected just once with a defined viral strain. Our results show how different single mutations help influenza virus escape the immunity of different members of the human population, a phenomenon that could shape viral evolution and disease susceptibility.


Assuntos
Anticorpos Antivirais/sangue , Variação Genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Evasão da Resposta Imune , Influenza Humana/virologia , Mutação , Orthomyxoviridae/imunologia , Animais , Furões , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Influenza Humana/imunologia , Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Soro/imunologia
14.
PLoS Comput Biol ; 15(8): e1007294, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31425503

RESUMO

The strength and breadth of an individual's antibody repertoire is an important predictor of their response to influenza infection or vaccination. Although progress has been made in understanding qualitatively how repeated exposures shape the antibody mediated immune response, quantitative understanding remains limited. We developed a set of mathematical models describing short-term antibody kinetics following influenza infection or vaccination and fit them to haemagglutination inhibition (HI) titres from 5 groups of ferrets which were exposed to different combinations of trivalent inactivated influenza vaccine (TIV with or without adjuvant), A/H3N2 priming inoculation and post-vaccination A/H1N1 inoculation. We fit models with various immunological mechanisms that have been empirically observed but have not previously been included in mathematical models of antibody landscapes, including: titre ceiling effects, antigenic seniority and exposure-type specific cross reactivity. Based on the parameter estimates of the best supported models, we describe a number of key immunological features. We found quantifiable differences in the degree of homologous and cross-reactive antibody boosting elicited by different exposure types. Infection and adjuvanted vaccination generally resulted in strong, broadly reactive responses whereas unadjuvanted vaccination resulted in a weak, narrow response. We found that the order of exposure mattered: priming with A/H3N2 improved subsequent vaccine response, and the second dose of adjuvanted vaccination resulted in substantially greater antibody boosting than the first. Either antigenic seniority or a titre ceiling effect were included in the two best fitting models, suggesting a role for a mechanism describing diminishing antibody boosting with repeated exposures. Although there was considerable uncertainty in our estimates of antibody waning parameters, our results suggest that both short and long term waning were present and would be identifiable with a larger set of experiments. These results highlight the potential use of repeat exposure animal models in revealing short-term, strain-specific immune dynamics of influenza.


Assuntos
Anticorpos Antivirais/sangue , Furões/imunologia , Vacinas contra Influenza/administração & dosagem , Modelos Imunológicos , Infecções por Orthomyxoviridae/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Biologia Computacional , Reações Cruzadas , Modelos Animais de Doenças , Humanos , Imunização Secundária , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Cinética , Infecções por Orthomyxoviridae/virologia , Vacinas de Produtos Inativados/administração & dosagem
15.
Nat Commun ; 10(1): 3737, 2019 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-31427581

RESUMO

Hepatitis E virus (HEV) is one of the leading causes of acute viral hepatitis worldwide. In this work, a pulse-triggered ultrasensitive electrochemical sensor was fabricated using graphene quantum dots and gold-embedded polyaniline nanowires, prepared via an interfacial polymerization and then self-assembly approach. Introducing an external electrical pulse during the virus accumulation step increases the sensitivity towards HEV due to the expanded surface of the virus particle as well as the antibody-conjugated polyaniline chain length, compared to other conventional electrochemical sensors. The sensor was applied to various HEV genotypes, including G1, G3, G7 and ferret HEV obtained from cell culture supernatant and in a series of fecal specimen samples collected from G7 HEV-infected monkey. The sensitivity is similar to that detected by real-time quantitative reverse transcription-polymerase chain (RT-qPCR). These results suggests that the proposed sensor can pave the way for the development of robust, high-performance sensing methodologies for HEV detection.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Vírus da Hepatite E/isolamento & purificação , Hepatite E/diagnóstico , Compostos de Anilina/química , Animais , Linhagem Celular Tumoral , Fezes/virologia , Furões/virologia , Ouro/química , Grafite/química , Hepatite E/virologia , Humanos , Macaca fascicularis/virologia , Mariposas/virologia , Nanofios/química , Pontos Quânticos/química , Sensibilidade e Especificidade
16.
Nat Commun ; 10(1): 3019, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31289272

RESUMO

Auditory cortex is required for sound localisation, but how neural firing in auditory cortex underlies our perception of sound sources in space remains unclear. Specifically, whether neurons in auditory cortex represent spatial cues or an integrated representation of auditory space across cues is not known. Here, we measured the spatial receptive fields of neurons in primary auditory cortex (A1) while ferrets performed a relative localisation task. Manipulating the availability of binaural and spectral localisation cues had little impact on ferrets' performance, or on neural spatial tuning. A subpopulation of neurons encoded spatial position consistently across localisation cue type. Furthermore, neural firing pattern decoders outperformed two-channel model decoders using population activity. Together, these observations suggest that A1 encodes the location of sound sources, as opposed to spatial cue values.


Assuntos
Córtex Auditivo/fisiologia , Vias Auditivas/fisiologia , Neurônios/fisiologia , Localização de Som/fisiologia , Estimulação Acústica/instrumentação , Estimulação Acústica/métodos , Potenciais de Ação/fisiologia , Animais , Córtex Auditivo/citologia , Comportamento Animal/fisiologia , Sinais (Psicologia) , Feminino , Furões , Microeletrodos , Modelos Animais
17.
AAPS PharmSciTech ; 20(6): 242, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31264190

RESUMO

The utilization of ferrets as a non-clinical model for disease is rapidly increasing within drug development. Many of these models include respiratory diseases that involve targeted drug delivery via nose-only inhalation. While the deposition patterns within other non-clinical models (mice, rats, canines, and non-human primates) have been well studied, the local and regional deposition of aerosols in ferrets has not been well characterized. Therefore, inhalation aerosols were developed, radiolabeled and the radiolabeling methods validated to support SPECT-CT imaging and quantification of regional deposition within ferrets. The studies were conducted with one liquid formulation and one dry powder formulation (two concentrations of dry powder). Additionally, both aerosols were polydisperse and therefore reflect the majority of pharmaceutical aerosols. Overall, the studies showed lung deposition fractions between 5 and 10% with median aerodynamic particle sizes of 2.5 and 2.8 µm. The lung deposition fraction of the liquid aerosol was ~ 9%, nearly double observed in rats with a similarly sized aerosol. Analysis of respiratory tract (oropharynx, laryngopharynx, trachea, bifurcation area, and lung) deposition indicates increased deposition of the liquid aerosol compared to the dry powder aerosol, however, when this analysis was refined to the pulmonary region (trachea, bifurcation, and lung) the deposition was similar between formulations. These data provide the first description of the regional deposition of inhalation aerosols in ferrets with standard nose-only inhalation procedures. These data can be used for calculations of both total and regional doses within ferret inhalation drug delivery.


Assuntos
Aerossóis/farmacocinética , Sistemas de Liberação de Medicamentos , Pulmão/metabolismo , Pós , Administração por Inalação , Animais , Furões , Humanos , Camundongos , Nebulizadores e Vaporizadores , Tamanho da Partícula , Ratos
18.
J Zoo Wildl Med ; 50(2): 487-491, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31260221

RESUMO

A 47-day-old black-footed ferret (Mustela nigripes) kit was found dead in June 2016. Histologic examination revealed pyogranulomatous tubulointerstitial nephritis, pneumonia, and encephalitis, with intralesional microsporidia. Transmission electron microscopic examination showed microsporidia with ultrastructural characteristics consistent with Encephalitozoon spp. Polymerase chain reaction (PCR) and direct sequencing confirmed the presence of Encephalitozoon cuniculi genotype II. This organism has been reported in other Carnivora (i.e., canids, felids, mustelids, procyonids, otariids). In humans, it is generally described as an opportunistic pathogen in immunocompromised individuals. The source of infection in the quarantine facility remains unknown, although two groups of frozen feeder rat kidneys tested positive for E. cuniculi genotype II via PCR. Feeding whole prey to various zoo taxa carries some potential disease transmission risk.


Assuntos
Encephalitozoon cuniculi , Encefalitozoonose/veterinária , Furões/parasitologia , Animais , Encefalitozoonose/patologia , Evolução Fatal
19.
Nat Commun ; 10(1): 3075, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300665

RESUMO

The brain has a remarkable capacity to adapt to changes in sensory inputs and to learn from experience. However, the neural circuits responsible for this flexible processing remain poorly understood. Using optogenetic silencing of ArchT-expressing neurons in adult ferrets, we show that within-trial activity in primary auditory cortex (A1) is required for training-dependent recovery in sound-localization accuracy following monaural deprivation. Because localization accuracy under normal-hearing conditions was unaffected, this highlights a specific role for cortical activity in learning. A1-dependent plasticity appears to leave a memory trace that can be retrieved, facilitating adaptation during a second period of monaural deprivation. However, in ferrets in which learning was initially disrupted by perturbing A1 activity, subsequent optogenetic suppression during training no longer affected localization accuracy when one ear was occluded. After the initial learning phase, the reweighting of spatial cues that primarily underpins this plasticity may therefore occur in A1 target neurons.


Assuntos
Córtex Auditivo/fisiologia , Aprendizagem/fisiologia , Localização de Som/fisiologia , Estimulação Acústica , Animais , Córtex Auditivo/citologia , Feminino , Furões , Modelos Animais , Rede Nervosa/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/fisiologia , Optogenética
20.
In Vivo ; 33(4): 1143-1150, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31280203

RESUMO

BACKGROUND: This study evaluated the effectiveness of a regenerative endodontic approach to regenerate the pulp tissue in mature teeth of ferret. The presence of odontoblast-like cells in the newly-formed tissue of teeth treated with or without preameloblast-conditioned medium was evaluated based on morphological criteria. MATERIALS AND METHODS: Twenty-four canines from six ferrets were treated. The pulp was removed, and the apical foramen was enlarged. After inducing the formation of a blood clot, a collagen sponge with or without preameloblast-conditioned medium was placed underneath the cementoenamel junction. The samples were analyzed at the eighth week of follow-up. RESULTS: Vascularized connective tissue was observed in 50% of teeth, without differences between groups. The tissue occupied the apical third of the root canals. Odontoblast-like cells were not observed in any group. CONCLUSION: Revitalization of mature teeth is possible, at least in the apical third of the root canal. Further experimental research is needed to produce more reliable outcomes.


Assuntos
Ameloblastos/metabolismo , Meios de Cultivo Condicionados/farmacologia , Órgão do Esmalte/citologia , Odontogênese , Endodontia Regenerativa , Ameloblastos/citologia , Animais , Furões , Odontogênese/efeitos dos fármacos , Ratos , Regeneração , Endodontia Regenerativa/métodos , Roedores , Dente/citologia , Dente/metabolismo
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