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Louping ill virus (LIV) is a tick-borne flavivirus that predominantly causes disease in livestock, especially sheep in the British Isles. A preventive vaccine, previously approved for veterinary use but now discontinued, was based on an inactivated whole virion that likely provided protection by induction of neutralizing antibodies recognizing the viral envelope (E) protein. A major disadvantage of the inactivated vaccine was the need for high containment facilities for the propagation of infectious virus, as mandated by the hazard group 3 status of the virus. This study aimed to develop high-efficacy non-infectious protein-based vaccine candidates. Specifically, soluble envelope protein (sE), and virus-like particles (VLPs), comprised of the precursor of membrane and envelope proteins, were generated, characterized, and studied for their immunogenicity in mice. Results showed that the VLPs induced more potent virus neutralizing response compared to sE, even though the total anti-envelope IgG content induced by the two antigens was similar. Depletion of anti-monomeric E protein antibodies from mouse immune sera suggested that the neutralizing antibodies elicited by the VLPs targeted epitopes spanning the highly organized structure of multimer of the E protein, whereas the antibody response induced by sE focused on E monomers. Thus, our results indicate that VLPs represent a promising LIV vaccine candidate.
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Vírus da Encefalite Transmitidos por Carrapatos , Vacinas de Partículas Semelhantes a Vírus , Vacinas , Animais , Camundongos , Ovinos , Anticorpos Neutralizantes , Anticorpos Antivirais , Proteínas do Envelope ViralRESUMO
Poxviridae is a family of enveloped, brick-shaped or ovoid viruses. The genome is a linear molecule of dsDNA (128-375 kbp) with covalently closed ends. The family includes the sub-families Entomopoxvirinae, whose members have been found in four orders of insects, and Chordopoxvirinae, whose members are found in mammals, birds, reptiles and fish. Poxviruses are important pathogens in various animals, including humans, and typically result in the formation of lesions, skin nodules, or disseminated rash. Infections can be fatal. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Poxviridae, which is available at ictv.global/report/poxviridae.
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Poxviridae , Animais , Humanos , Poxviridae/genética , Peixes , Aves , Mamíferos , Répteis , Genoma Viral , Replicação Viral , VírionRESUMO
Traumatic thumb injuries often result in significant functional disability. With segmental bone loss, reconstructive options include antibiotic cement with delayed bone graft, revision amputation with webspace deepening, metacarpal distraction osteogenesis, index pollicization, bone flap, and free toe transfer. We present a case of a subtotal thumb amputation just distal to the metacarpal phalangeal joint resulting in loss of both soft tissue and a segmental bone defect of the proximal and distal phalanx. Reconstruction was initially performed with a chimeric bone free flap from the medial femoral condyle with a vastus medialis muscle cuff to provide soft tissue coverage. A revision soft tissue coverage procedure was required and a radial forearm free flap was utilized. His reconstruction restored his missing bone and soft tissue, and provided stability with sufficient grip strength and metacarpophalangeal function resulting in a satisfactory functional outcome.
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Amputação Traumática , Retalhos de Tecido Biológico , Ossos Metacarpais , Humanos , Polegar , Amputação Traumática/cirurgia , Ossos Metacarpais/cirurgia , MúsculosRESUMO
OBJECTIVE: Partial femoral nerve injuries cause significant disability with ambulation. Due to their more proximal and superficial location, sartorius branches are often spared in femoral nerve injuries. In this article, the authors report the benefits of femoral nerve decompression, demonstrate the feasibility of sartorius-to-quadriceps nerve transfers in a cadaveric study, describe the surgical technique, and report clinical results. METHODS: Four fresh-frozen cadaveric lower limbs were dissected for anatomical analysis of the sartorius nerve. In addition, a retrospective review of patients with partial femoral nerve injuries treated with femoral nerve decompression and sartorius-to-quadriceps nerve transfers was conducted. Pre- and postoperative knee extension Medical Research Council (MRC) grades and pain scores (visual analog scale) were collected. RESULTS: Up to 6 superficial femoral branches innervate the sartorius muscle just distal to the inguinal ligament. Each branch yielded an average of 672 nerve fibers (range 99-1850). Six patients underwent femoral nerve decompression and sartorius-to-quadriceps nerve transfers. Four patients also had concomitant obturator-to-quadriceps nerve transfers. At final follow-up (average 13.4 months), all patients achieved MRC grade 4-/5 or greater knee extension. The average preoperative pain score was 5.2, which decreased to 2.2 postoperatively (p = 0.03). CONCLUSIONS: Femoral nerve decompression and nerve transfer using sartorius branches are a viable tool for restoring function in partial femoral nerve injuries. Sartorius branches serve as ideal donors in quadriceps nerve transfers because they are expendable, are close to their recipients, and have an adequate supply of nerve fibers.
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The emergence and spread of tick-borne arboviruses pose an increased challenge to human and animal health. In Europe this is demonstrated by the increasingly wide distribution of tick-borne encephalitis virus (TBEV, Flavivirus, Flaviviridae), which has recently been found in the United Kingdom (UK). However, much less is known about other tick-borne flaviviruses (TBFV), such as the closely related louping ill virus (LIV), an animal pathogen which is endemic to the UK and Ireland, but which has been detected in other parts of Europe including Scandinavia and Russia. The emergence and potential spatial overlap of these viruses necessitates improved understanding of LIV genomic diversity, geographic spread and evolutionary history. We sequenced a virus archive composed of 22 LIV isolates which had been sampled throughout the UK over a period of over 80 years. Combining this dataset with published virus sequences, we detected no sign of recombination and found low diversity and limited evidence for positive selection in the LIV genome. Phylogenetic analysis provided evidence of geographic clustering as well as long-distance movement, including movement events that appear recent. However, despite genomic data and an 80-year time span, we found that the data contained insufficient temporal signal to reliably estimate a molecular clock rate for LIV. Additional analyses revealed that this also applied to TBEV, albeit to a lesser extent, pointing to a general problem with phylogenetic dating for TBFV. The 22 LIV genomes generated during this study provide a more reliable LIV phylogeny, improving our knowledge of the evolution of tick-borne flaviviruses. Our inability to estimate a molecular clock rate for both LIV and TBEV suggests that temporal calibration of tick-borne flavivirus evolution should be interpreted with caution and highlight a unique aspect of these viruses which may be explained by their reliance on tick vectors.
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Vírus da Encefalite Transmitidos por Carrapatos/genética , Evolução Molecular , Genoma Viral , Animais , Linhagem Celular , Cricetinae , Vírus da Encefalite Transmitidos por Carrapatos/classificação , Encefalite Transmitida por Carrapatos/virologia , Genética Populacional , Metagenômica , Filogenia , Análise de Sequência de RNA , Ovinos , Reino UnidoRESUMO
BACKGROUND: Overprescribing following surgery is a known contributor to the opioid epidemic, increasing the risk of opioid abuse and diversion. Trainees are the primary prescribers of these medications at academic institutions, and little is known about the factors that influence their prescribing. The authors hypothesized that differences in health care funding and delivery would lead to disparities in opioid prescribing. Therefore, the authors sought to compare the prescribing practices of plastic surgery trainees in the United States and Canada. METHODS: A survey was administered to trainees at a sample of U.S. and Canadian institutions. The survey queried opioid-prescriber education, factors contributing to prescribing practices, and analgesic prescriptions written after eight procedures. Oral morphine equivalents were calculated for each procedure and compared between groups. RESULTS: One hundred sixty-two trainees completed the survey, yielding a response rate of 32 percent. Opioid-prescriber education was received by 25 percent of U.S. and 53 percent of Canadian trainees (p < 0.0001). Preoperative counseling was performed routinely by only 11 percent of U.S. and 14 percent of Canadian trainees. U.S. trainees prescribed significantly more oral morphine equivalents than Canadians for seven of eight procedures (p < 0.05). Residency training in the United States and junior training level independently predicted higher oral morphine equivalents prescribed (p < 0.05). CONCLUSIONS: U.S. trainees prescribed significantly more opioids than their Canadian counterparts for seven of eight procedures surveyed. Many trainees are missing a valuable opportunity to provide opioid counseling to patients. Standardizing trainee education may represent an opportunity to reduce overprescribing.
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Analgésicos Opioides/uso terapêutico , Prescrições de Medicamentos/estatística & dados numéricos , Dor Pós-Operatória/tratamento farmacológico , Padrões de Prática Médica/estatística & dados numéricos , Cirurgia Plástica/estatística & dados numéricos , Adulto , Canadá , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Manejo da Dor/métodos , Estados UnidosRESUMO
BACKGROUND: Lower extremity soft tissue sarcoma treatment has evolved from primarily amputation procedures toward limb salvage. This series assesses whether soft tissue sarcoma tissue defects, extensive enough to require microsurgical reconstruction, can reliably result in preservation of ambulation, as well as objectively evaluate functional outcomes utilizing a patient-reported validated scale. It will also look at whether immediate functional muscle reconstructions and tendon transfers can be successful at restoring ambulation, potentially expanding the indications for limb salvage procedures. METHODS: A retrospective review of all microsurgical reconstructions for limb salvage in lower extremity sarcoma patients was completed at our institution (2009-2013). Patients were additionally asked to complete the Toronto Extremity Salvage Score(TESS) quality of life survey. RESULTS: Over a 5-year period, 23 patients (mean age: 53 years) underwent free flap reconstructions for 23 sarcomas (mean follow-up: 14 months). Seventy-eight percent of patients received neoadjuvant radiation. The thigh was the most common tumor site (61%) and three muscles were resected on average. Perforator flaps were most frequently used (61%), and functional muscle transfers or immediate tendon transfers were used in four patients. There were no flap take-backs or failures, and 22 patients achieved independent ambulation. Three patients in the series died, two from metastatic disease found postoperatively and one from local recurrence. A 74% response rate was achieved for the TESS survey, with a mean score of 83. CONCLUSION: Microsurgical reconstruction of lower extremity sarcoma defects enables preservation of independent ambulation. Restoration of function utilizing immediate functional microsurgical reconstructions and tendon transfers should be considered.
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Retalhos de Tecido Biológico/irrigação sanguínea , Salvamento de Membro/métodos , Extremidade Inferior/patologia , Procedimentos de Cirurgia Plástica/métodos , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Amputação Cirúrgica/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Estudos Retrospectivos , Sarcoma/patologia , Neoplasias de Tecidos Moles/patologia , CaminhadaRESUMO
BACKGROUND: The impact of resident work hour restrictions on training and patient care remains a highly controversial topic, and to date, there lacks a formal assessment as it pertains to Canadian plastic surgery residents. OBJECTIVE: To characterize the work hour profile of Canadian plastic surgery residents and assess the perspectives of residents and program directors regarding work hour restrictions related to surgical competency, resident wellness, and patient safety. METHODS: An anonymous online survey developed by the authors was sent to all Canadian plastic surgery residents and program directors. Basic summary statistics were calculated. RESULTS: Eighty (53%) residents and 10 (77%) program directors responded. Residents reported working an average of 73 hours in hospital per week with 8 call shifts per month and sleep 4.7 hours/night while on call. Most residents (88%) reported averaging 0 post-call days off per month and 61% will work post-call without any sleep. The majority want the option of working post-call (63%) and oppose an 80-hour weekly maximum (77%). Surgical and medical errors attributed to post-call fatigue were self-reported by 26% and 49% of residents, respectively. Residents and program directors expressed concern about the ability to master surgical skills without working post-call. CONCLUSIONS: The majority of respondents oppose duty hour restrictions. The reason is likely multifactorial, including the desire of residents to meet perceived expectations and to master their surgical skills while supervised. If duty hour restrictions are aggressively implemented, many respondents feel that an increased duration of training may be necessary.
HISTORIQUE: L'effet des restrictions des heures de travail des résidents sur la formation et les soins aux patients est un sujet très controversé. Jusqu'à présent, il n'y a pas d'évaluations officielles de cette réalité chez les résidents canadiens en chirurgie plastique. OBJECTIF: Caractériser le profil des heures de travail des résidents canadiens en chirurgie plastique et évaluer les points de vue des résidents et des directeurs de programme à l'égard de l'effet des restrictions des heures de travail sur la compétence chirurgicale, le bien-être des résidents et la sécurité des patients. MÉTHODOLOGIE: Les auteurs ont préparé un sondage anonyme en ligne qu'ils ont transmis à tous les résidents et les directeurs de programme en chirurgie plastique au Canada. Ils ont synthétisé les statistiques de base. RÉSULTATS: Au total, 80 résidents (53 %) et dix directeurs de programme (77 %) ont répondu au sondage. Les résidents ont déclaré faire une moyenne de 73 heures de travail hospitalier par semaine, faire huit quarts de garde par mois et dormir 4,7 heures par nuit lorsqu'ils sont sur appel. La plupart d'entre eux (88 %) déclarent une moyenne de 0 journée de congé après une garde, et 61 % travaillent ensuite sans avoir dormi. La majorité désire pouvoir travailler après une garde (63 %) et s'oppose à un maximum hebdomadaire de 80 heures (77 %). Par ailleurs, 26 % des résidents précisent avoir fait des erreurs chirurgicales et 49 %, des erreurs médicales qu'ils attribuent à la fatigue accumulée après une garde. Les résidents et les directeurs de programme s'inquiètent de la capacité des résidents à maîtriser les habiletés chirurgicales s'ils ne travaillent pas après les gardes. CONCLUSIONS: La majorité des répondants s'opposent aux restrictions des heures de garde. La raison est probablement multifactorielle, y compris le fait que les résidents souhaitent répondre aux attentes perçues et maîtriser leurs habiletés chirurgicales pendant qu'ils sont sous supervision. Si les restrictions des heures de garde étaient vigoureusement adoptées, de nombreux répondants croient qu'il faudrait allonger la formation.
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Anticorpos Antivirais/isolamento & purificação , Infecções por Poxviridae/veterinária , Poxviridae/imunologia , Doenças dos Roedores/imunologia , Sciuridae/virologia , Animais , Infecções por Poxviridae/imunologia , Infecções por Poxviridae/virologia , Doenças dos Roedores/virologia , Reino UnidoRESUMO
Successful mammalian pregnancies are a result of complex physiological, endocrinological, and immunological processes that combine to create an environment where the mother is tolerant to the semi-allogeneic fetus. Our knowledge of the mechanisms that contribute to maternal tolerance is derived mainly from human and murine studies of haemochorial placentation. However, as this is the most invasive type of placentation it cannot be assumed that identical mechanisms apply to the less invasive epitheliochorial placentation found in other species such as ruminants. Here, we examine three features associated with reproductive immune regulation in a transformed ovine trophoblast cell line and ex-vivo ovine reproductive tissues collected at term, namely: major histocompatibility complex (MHC) expression, Indoleamine 2,3 dioxygenase-1 (IDO-1) expression, and Natural Killer (NK) cell infiltration. High levels of MHC class I protein expression were detected at the surface of the trophoblast cell line using a pan-MHC class I specific monoclonal antibody. The majority of MHC class I transcripts isolated from the cell line clustered with classical MHC alleles. Transcriptional analysis of placental tissues identified only classical MHC class I transcripts. We found no evidence of constitutive transcription of IDO-1 in either the trophoblast cell line or placental tissues. Ex-vivo tissues collected from the materno-fetal interface were negative for cells expressing NKp46/NCR1. Collectively, these observations suggest that the relatively non-invasive synepitheliochorial placentation found in sheep has a more limited requirement for local immunoregulation compared to the more invasive haemochorial placentation of primates and rodents.
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Homeostase/imunologia , Troca Materno-Fetal/imunologia , Placenta/fisiologia , Ovinos/fisiologia , Animais , Biomarcadores , Linhagem Celular , Feminino , Expressão Gênica , Imunofenotipagem , Complexo Principal de Histocompatibilidade/genética , Complexo Principal de Histocompatibilidade/imunologia , Receptor 1 Desencadeador da Citotoxicidade Natural/genética , Receptor 1 Desencadeador da Citotoxicidade Natural/metabolismo , Filogenia , Gravidez , Análise de Sequência de DNA , Trofoblastos/metabolismoRESUMO
A chain of tether-connected payload masses assembled from the surface material of a spherical rotating asteroid is envisaged as a means of delivering a fraction of the asteroid mass into orbit, without the need of external work to be done. Under conditions to be discussed, a net radial force is established on the chain which can be exploited to initialize an orbital siphon effect: new payloads are connected to the chain while top payloads are removed and released into orbit. Adopting simplifying assumptions, the underlying dynamics of the problem is entirely analytical and is investigated in detail. The amount of mass extractable from the asteroid is then discussed, according to a range of strategies. It is proposed that the scheme could in future provide an efficient means of extracting material resources from rotating Near Earth Asteroids.
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Virus infection of humans and livestock can be devastating for individuals and populations, sometimes resulting in large economic and societal impact. Prevention of virus disease by vaccination or antiviral agents is difficult to achieve. A notable exception was the eradication of human smallpox by vaccination over 30 years ago. Today, humans and animals remain susceptible to poxvirus infections, including zoonotic poxvirus transmission. Here we identified a small molecule, bisbenzimide (bisbenzimidazole), and its derivatives as potent agents against prototypic poxvirus infection in cell culture. We show that bisbenzimide derivatives, which preferentially bind the minor groove of double-stranded DNA, inhibit vaccinia virus infection by blocking viral DNA replication and abrogating postreplicative intermediate and late gene transcription. The bisbenzimide derivatives are potent against vaccinia virus and other poxviruses but ineffective against a range of other DNA and RNA viruses. The bisbenzimide derivatives are the first inhibitors of their class, which appear to directly target the viral genome without affecting cell viability.IMPORTANCE Smallpox was one of the most devastating diseases in human history until it was eradicated by a worldwide vaccination campaign. Due to discontinuation of routine vaccination more than 30 years ago, the majority of today's human population remains susceptible to infection with poxviruses. Here we present a family of bisbenzimide (bisbenzimidazole) derivatives, known as Hoechst nuclear stains, with high potency against poxvirus infection. Results from a variety of assays used to dissect the poxvirus life cycle demonstrate that bisbenzimides inhibit viral gene expression and genome replication. These findings can lead to the development of novel antiviral drugs that target viral genomes and block viral replication.
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Antivirais/farmacologia , Bisbenzimidazol/farmacologia , Replicação do DNA/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos , Vaccinia virus/efeitos dos fármacos , Vaccinia virus/fisiologia , Replicação Viral/efeitos dos fármacos , Animais , Linhagem Celular , Corantes Fluorescentes , HumanosRESUMO
The development of methods to detect cytokine expression by T cell subsets in ruminants is fundamental to strategic development of new livestock vaccines for prevention of infectious diseases. It has been possible to detect T cell expression of IFN-γ, IL-4 and IL-10 in ruminants for many years but methods to detect expression of IL-17A are relatively limited. To address this gap in capability we have cloned bovine and ovine IL-17A cDNAs and expressed biologically-active recombinant proteins in Chinese Hamster Ovary (CHO) cells. We used the transfected CHO cells to screen commercially-available antibodies for their ability to detect IL-17A expression intracellularly and in culture supernates. We demonstrate that an ELISA for bovine IL-17A detects native ovine IL-17A. Moreover, the constituent polyclonal antibodies (pabs) in the ELISA were used to enumerate peripheral blood mononuclear cells (PBMC) expressing IL-17A from cattle and sheep by ELISpot. We identified two monoclonal antibodies (mabs) that detect recombinant intracellular IL-17A in CHO cells by flow cytometry. One of these mabs was used to detect native intracellular IL-17A expression in PBMC in conjunction with cell surface phenotyping mabs [CD4+ve, CD8+ve and Workshop Cluster 1 (WC-1)+ve gamma-delta (γδ)] we show that distinct T cell subsets in cattle (defined as CD4+ve, CD8+ve or WC-1+ve) and sheep (defined as CD4+ve or WC-1+ve) can express IL-17A following activation. These novel techniques provide a solid basis to investigate IL-17A expression and define specific CD4+ve T cell subset activation in ruminants.
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Bovinos/fisiologia , Interleucina-17/fisiologia , Ovinos/fisiologia , Animais , Anticorpos/imunologia , Células CHO , Bovinos/imunologia , Clonagem Molecular , Cricetulus , Ensaio de Imunoadsorção Enzimática/veterinária , Interleucina-17/análise , Interleucina-17/genética , Interleucina-17/imunologia , Leucócitos Mononucleares/química , Análise de Sequência de DNA/veterinária , Ovinos/imunologia , Linfócitos T/químicaRESUMO
A reconfigurable smart surface with multiple equilibria is presented, modelled using discrete point masses and linear springs with geometric nonlinearity. An energy-efficient reconfiguration scheme is then investigated to connect equal-energy unstable (but actively controlled) equilibria. In principle, zero net energy input is required to transition the surface between these unstable states, compared to transitions between stable equilibria across a potential barrier. These transitions between equal-energy unstable states, therefore, form heteroclinic connections in the phase space of the problem. Moreover, the smart surface model developed can be considered as a unit module for a range of applications, including modules which can aggregate together to form larger distributed smart surface systems.
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BACKGROUND: The upper thigh has provided multiple new soft tissue free flaps in recent decades, including the anterolateral thigh, anteromedial thigh, transverse upper gracilis, the profunda artery perforator, and superficial circumflex iliac perforator flaps. The purpose of this study is to describe a new, reliable free flap option in the upper thigh: the proximal superficial femoral artery perforator (p-SFAP) flap. METHODS: A cadaveric dissection study was performed to confirm clinical landmarks and evaluate pedicle characteristics. A retrospective review of patients who have received a p-SFAP free flap and surgical technique are described in detail. Eight patients (aged 27-85 years) underwent reconstruction with the p-SFAP flap involving six upper and two lower extremity defects. RESULTS: A consistent pedicle 6 to 8 cm in length was identified in all cadaveric and clinical limbs, emerging from under the lateral aspect of the sartorius muscle and entering the flap approximately 10 cm inferior and 4 cm medial to the anterior superior iliac spine. The perforator took origin off of the superficial femoral artery and femoral vein in all clinical cases. Arterial and venous diameters were 1.2-1.5 mm and 2.0-2.5 mm, respectively. There was one occurrence of partial flap necrosis and one case of complete flap loss. CONCLUSIONS: The p-SFAP flap represents a new, clinically relevant addition to the armamentarium of the reconstructive microsurgeon for use in small to medium sized defects. It can be harvested as a free flap and may have utility as a pedicled flap for groin and perineal reconstruction.
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Artéria Femoral/cirurgia , Retalho Perfurante/irrigação sanguínea , Procedimentos de Cirurgia Plástica/métodos , Coxa da Perna/cirurgia , Cicatrização/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Traumatismos do Braço/cirurgia , Cadáver , Estudos de Coortes , Dissecação , Feminino , Artéria Femoral/transplante , Sobrevivência de Enxerto , Humanos , Traumatismos da Perna/cirurgia , Masculino , Microcirurgia/métodos , Pessoa de Meia-Idade , Retalho Miocutâneo/irrigação sanguínea , Retalho Miocutâneo/transplante , Retalho Perfurante/transplante , Qualidade de Vida , Medição de Risco , Coxa da Perna/anatomia & histologia , Resultado do TratamentoRESUMO
A horse in Finland exhibited generalized granulomatous inflammation and severe proliferative dermatitis. After euthanization, we detected poxvirus DNA from a skin lesion sample. The virus sequence grouped with parapoxviruses, closely resembling a novel poxvirus detected in humans in the United States after horse contact. Our findings indicate horses may be a reservoir for zoonotic parapoxvirus.