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1.
Int J Mol Sci ; 22(21)2021 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-34769480

RESUMO

A natural recombinant myxoma virus (referred to as ha-MYXV or MYXV-Tol08/18) emerged in the Iberian hare (Lepus granatensis) and the European rabbit (Oryctolagus cuniculus) in late 2018 and mid-2020, respectively. This new virus is genetically distinct from classic myxoma virus (MYXV) strains that caused myxomatosis in rabbits until then, by acquiring an additional 2.8 Kbp insert within the m009L gene that disrupted it into ORFs m009L-a and m009L-b. To distinguish ha-MYXV from classic MYXV strains, we developed a robust qPCR multiplex technique that combines the amplification of the m000.5L/R duplicated gene, conserved in all myxoma virus strains including ha-MYXV, with the amplification of two other genes targeted by the real-time PCR systems designed during this study, specific either for classic MYXV or ha-MYXV strains. The first system targets the boundaries between ORFs m009L-a and m009L-b, only contiguous in classic strains, while the second amplifies a fragment within gene m060L, only present in recombinant MYXV strains. All amplification reactions were validated and normalized by a fourth PCR system directed to a housekeeping gene (18S rRNA) conserved in eukaryotic organisms, including hares and rabbits. The multiplex PCR (mPCR) technique described here was optimized for Taqman® and Evagreen® systems allowing the detection of as few as nine copies of viral DNA in the sample with an efficiency > 93%. This real-time multiplex is the first fast method available for the differential diagnosis between classic and recombinant MYXV strains, also allowing the detection of co-infections. The system proves to be an essential and effective tool for monitoring the geographical spread of ha-MYXV in the hare and wild rabbit populations, supporting the management of both species in the field.


Assuntos
Lagomorpha/virologia , Myxoma virus , Mixomatose Infecciosa/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Animais Selvagens , Diagnóstico Diferencial , Transferência Genética Horizontal/genética , Tipagem Molecular/métodos , Tipagem Molecular/veterinária , Myxoma virus/classificação , Myxoma virus/genética , Mixomatose Infecciosa/virologia , Coelhos , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espanha
2.
An Acad Bras Cienc ; 87(1): 437-45, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25651154

RESUMO

The aim of this study was to analyze the correlation between triglyceride (TG) serum levels in obese and non-obese patients in a simulated postprandial state. Both groups showed TG levels < 150 mg/dL when fasting. After 12 h fasting, the subjects ingested a lipid overload diet and blood samples were collected. The variation between fasting and the postprandial TG peak levels were analyzed. The peak of postprandial TG levels occurred 4 h after the lipid overload in both groups. When the subjects were not fasting, the majority of non-obese subjects remained within the range of normal TG values, but the values for the obese group remained elevated. There was a significant correlation between Body Mass Index (BMI) and TG at each time point until 2 h after the meal, but the data did not show a correlation after 3 h. According to the receiver-operating characteristics (ROC) curve, postprandial TG values were not a good predictor of obesity (based on BMI), but they were a predictor of non-obesity. This study reinforces the importance of measuring non-fasting TG levels in obese and non-obese subjects, because some non-obese patients probably had altered fat metabolism, indicating that this examination could be an indicator of metabolic risk.


Assuntos
Hipertrigliceridemia/etiologia , Metabolismo dos Lipídeos/fisiologia , Obesidade/sangue , Período Pós-Prandial , Triglicerídeos/sangue , Adulto , Índice de Massa Corporal , Feminino , Humanos , Hipertrigliceridemia/sangue , Hipertrigliceridemia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/fisiopatologia , Valor Preditivo dos Testes , Curva ROC , Fatores de Tempo
3.
ScientificWorldJournal ; 2015: 617401, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25767824

RESUMO

Leishmaniasis is considered by the World Health Organization as one of the infectious parasitic diseases endemic of great relevance and a global public health problem. Pentavalent antimonials used for treatment of this disease are limited and new phytochemicals emerge as an alternative to existing treatments, due to the low toxicity and cost reduction. Usnic acid is uniquely found in lichens and is especially abundant in genera such as Alectoria, Cladonia, Evernia, Lecanora, Ramalina, and Usnea. Usnic acid has been shown to exhibit antiviral, antiprotozoal, antiproliferative, anti-inflammatory, and analgesic activity. The aim of this study was to evaluate the antileishmanial activity of usnic acid on Leishmania infantum chagasi promastigotes and the occurrence of drug-induced ultrastructural damage in the parasite. Usnic acid was effective against the promastigote forms (IC50=18.30±2.00 µg/mL). Structural and ultrastructural aspects of parasite were analyzed. Morphological alterations were observed as blebs in cell membrane and shapes given off, increasing the number of cytoplasmic vacuoles, and cellular and mitochondrial swelling, with loss of cell polarity. We concluded that the usnic acid presented antileishmanial activity against promastigote forms of Leishmania infantum chagasi and structural and ultrastructural analysis reinforces its cytotoxicity. Further, in vitro studies are warranted to further evaluate this potential.


Assuntos
Benzofuranos/farmacologia , Leishmania infantum/ultraestrutura , Animais , Técnicas In Vitro , Leishmania infantum/efeitos dos fármacos
4.
J Prosthodont ; 24(7): 594-597, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25675972

RESUMO

The objective of this study is to report the clinical use of 2% Uncaria tomentosa gel against denture stomatitis (DS) as an alternative treatment. The patient was a 65-year-old, denture-wearing woman. At the clinical examination, her palate showed hyperplasic and erythematous mucosa indicating DS type II. DS is a chronic oral disease that affects denture wearers. It occurs as an inflammatory reaction in denture-wearing patients under maxillary prostheses. Candida albicans has been reported as the principal etiological agent. An alternative treatment, the topical application of a gel of 2% U. tomentosa three times a day for 1 week was given to the patient. After 1 week of this treatment, she had significantly reduced signs of the disease. Despite the existence of a great number of antifungal agents, treatment failure is observed frequently. Phytotherapy is becoming more popular worldwide. Currently, the most promising medicinal Amazonian herb is U. tomentosa (Willd.) DC., known as Cat's Claw. Studies of the chemical and pharmacological properties of this medicinal plant have allowed researchers to develop indications for its use. This report demonstrates the effectiveness of U. tomentosa against DS.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38430209

RESUMO

BACKGROUND: Various surgical approaches have been employed to manage gingival recession, including subepithelial connective tissue grafting, which has yielded favorable outcomes. METHODS AND RESULTS: We present the case of a 17-year-old patient who developed gingival recession on tooth #6 following an esthetic crown lengthening procedure. The recession was treated with a subepithelial connective tissue graft; however, this case details the occurrence of two epithelial cysts adjacent to the region subjected to the surgical procedure, 6 months after surgery. The treatment involved periodontal surgical intervention, during which the lesions were completely excised and the associated osseous defect was filled using an inorganic bovine bone matrix along with a collagen membrane. The healing progressed without any complications. Histopathological analysis revealed the presence of cystic lesions, which were characterized by a cystic cavity lined with stratified orthokeratinized epithelium with cuboidal cells in some areas surrounded by fibrous connective tissue. The patient's progress was monitored through tomography performed 6 months, 1 year, and 5 years post-procedure, all of which demonstrated the absence of any signs of lesion recurrence. CONCLUSION: This case study emphasizes the effectiveness and predictability of subepithelial connective tissue grafting in the treatment of gingival recession. However, dental professionals should be cautious about the potential risk of gingival recession following esthetic crown lengthening procedures and recognize the potential complications associated with subepithelial connective tissue grafting, such as the observed development of epithelial cysts in this specific case. KEY POINTS: Why is this case new information? We present a case of an epithelial cyst following a subepithelial connective tissue graft, which resulted in buccal cortical bone resorption. The treatment involved excisional biopsy and the use of an inorganic bovine bone matrix with a collagen membrane. What are the keys to the successful management of this case? Successful treatment included periodontal surgery, bone defect filling using an inorganic bovine bone matrix and a collagen membrane, and regular monitoring with CT scans at 6 months, 1 year, and 5 years post-surgery; all showed no recurrence. Success factors included careful surgery, appropriate biomaterial usage, and ongoing follow-up. What are the primary limitations to success in this case? The limitations involve potential complications from subepithelial connective tissue grafting such as cyst development. This report stresses the importance of meticulous patient selection and periodontal phenotype evaluation to minimize risks. Continuous follow-up is critical to detect recurrence and other issues.

6.
Viruses ; 16(6)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38932159

RESUMO

In virology, the term reverse genetics refers to a set of methodologies in which changes are introduced into the viral genome and their effects on the generation of infectious viral progeny and their phenotypic features are assessed. Reverse genetics emerged thanks to advances in recombinant DNA technology, which made the isolation, cloning, and modification of genes through mutagenesis possible. Most virus reverse genetics studies depend on our capacity to rescue an infectious wild-type virus progeny from cell cultures transfected with an "infectious clone". This infectious clone generally consists of a circular DNA plasmid containing a functional copy of the full-length viral genome, under the control of an appropriate polymerase promoter. For most DNA viruses, reverse genetics systems are very straightforward since DNA virus genomes are relatively easy to handle and modify and are also (with few notable exceptions) infectious per se. This is not true for RNA viruses, whose genomes need to be reverse-transcribed into cDNA before any modification can be performed. Establishing reverse genetics systems for members of the Caliciviridae has proven exceptionally challenging due to the low number of members of this family that propagate in cell culture. Despite the early successful rescue of calicivirus from a genome-length cDNA more than two decades ago, reverse genetics methods are not routine procedures that can be easily extrapolated to other members of the family. Reports of calicivirus reverse genetics systems have been few and far between. In this review, we discuss the main pitfalls, failures, and delays behind the generation of several successful calicivirus infectious clones.


Assuntos
Caliciviridae , Genética Reversa , Genética Reversa/métodos , Caliciviridae/genética , Genoma Viral , Animais , Humanos , Replicação Viral
7.
Sci Rep ; 14(1): 19452, 2024 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-39169115

RESUMO

Bagaza virus (BAGV) is a mosquito-borne flavivirus of the family Flaviviridae, genus Orthoflavivirus, Ntaya serocomplex. Like other viruses of the Ntaya and Japanese encephalitis serocomplexes, it is maintained in nature in transmission cycles involving viremic wild bird reservoirs and Culex spp. mosquitoes. The susceptibility of red-legged partridge, ring-necked pheasant, Himalayan monal and common wood pigeon is well known. Determining whether other species are susceptible to BAGV infection is fundamental to understanding the dynamics of disease transmission and maintenance. In September 2023, seven Eurasian magpies were found dead in a rural area in the Mértola district (southern Portugal) where a BAGV-positive cachectic red-legged partridge had been found two weeks earlier. BAGV had also been detected in several red-legged partridges in the same area in September 2021. Three of the magpies were tested for Bagaza virus, Usutu virus, West Nile virus, Avian influenza virus and Avian paramyxovirus serotype 1, and were positive for BAGV only. Sequencing data confirmed the specificity of the molecular detection. Our results indicate that BAGV is circulating in southern Portugal and confirm that Eurasian magpie is potential susceptible to BAGV infection. The inclusion of the abundant Eurasian magpie in the list of BAGV hosts raises awareness of the potential role of this species as as an amplifying host.


Assuntos
Flavivirus , Animais , Portugal , Flavivirus/genética , Flavivirus/isolamento & purificação , Filogenia , Doenças das Aves/virologia , Doenças das Aves/epidemiologia , Infecções por Flavivirus/virologia , Infecções por Flavivirus/veterinária , Infecções por Flavivirus/transmissão , Infecções por Flavivirus/epidemiologia
8.
Transbound Emerg Dis ; 69(4): 1684-1690, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35366052

RESUMO

Myxomatosis is an emergent disease in the Iberian hare (Lepus granatensis). In this species, the disease is caused by a natural recombinant virus (ha-myxoma virus [MYXV]) identified for the first time in 2018 and has since been responsible for a large number of outbreaks in Spain and Portugal. The ha-MYXV, which harbours a 2.8 Kb insert-disrupting gene M009L, can also infect and cause disease in wild and domestic rabbits, despite being less frequently identified in rabbits. During the laboratory investigations of wild leporids found dead in Portugal carried out within the scope of a Nacional Surveillance Plan (Dispatch 4757/17, MAFDR), co-infection events by classic (MYXV) and naturally recombinant (ha-MYXV) strains were detected in both one Iberian hare and one European wild rabbit (Oryctolagus cuniculus algirus). These two cases were initially detected by a multiplex qPCR detection of MYXV and ha-MYXV and subsequently confirmed by conventional PCR and sequencing of the M009L gene, which contains an ha-MYXV-specific insertion. To our knowledge, this is the first documented report of co-infection by classic MYXV and ha-MYXV strains either in Iberian hare or in European wild rabbit. It is also the first report of infection of an Iberian hare by a classic MYXV strain. These findings highlight the continuous evolution of the MYXV and the frequent host range changes that justify the nonstop monitoring of the sanitary condition of wild Leporidae populations in the Iberian Peninsula.


Assuntos
Coinfecção , Lebres , Myxoma virus , Animais , Coinfecção/epidemiologia , Coinfecção/veterinária , Especificidade de Hospedeiro , Myxoma virus/genética , Filogenia , Coelhos
9.
Microbiol Spectr ; 10(3): e0026922, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35506680

RESUMO

The antimicrobial properties of photocatalysts have long been studied. However, most of the available literature describes their antibacterial properties, while knowledge of their antiviral activity is rather scarce. Since the outset of the coronavirus disease 2019 (COVID-19) pandemic, an increasing body of research has suggested their antiviral potential and highlighted the need for further research in this area. In this study, we investigated the virucidal properties of a commercial TiO2-coated photocatalytic glass against a model human coronavirus. Our findings demonstrate that the TiO2-coated glass consistently inactivates coronaviruses upon contact under daylight illumination, in a time-dependent manner. A 99% drop in virus titer was achieved after 3.9 h. The electron micrographs of virus-covered TiO2-glass showed a reduced number of virions compared to control glass. Morphological alterations of TiO2-exposed viruses included deformation, disruption of the viral envelope, and virion ghosts, endorsing the application of this material in the construction of protective elements to mitigate the transmission of viruses. To the best of our knowledge, this is the first report showing direct visual evidence of human coronaviruses being damaged and morphologically altered following exposure to this photocatalyst. IMPORTANCE Surface contamination is an important contributor to SARS-CoV-2 spread. The use of personal protective elements and physical barriers (i.e., masks, gloves, and indoor glass separators) increases safety and has proven invaluable in preventing contagion. Redesigning these barriers so that the virus cannot remain infectious on them could make a difference in COVID-19 epidemiology. The introduction of additives with virucidal activity could potentiate the protective effects of these barriers to serve not only as physical containment but also as virus killers, reducing surface contamination after hand touch or aerosol deposition. We performed in-depth analysis of the kinetics of photocatalysis-triggered coronavirus inactivation on building glass coated with TiO2. This is the first report showing direct visual evidence (electron microscopy) of coronaviruses being morphologically damaged following exposure to this photocatalyst, demonstrating the high potential of this material to be incorporated into daily-life high-touch surfaces, giving them an added value in decelerating the virus spread.


Assuntos
COVID-19 , Vírus , Antivirais/farmacologia , COVID-19/prevenção & controle , Humanos , Pandemias , SARS-CoV-2
10.
Vaccines (Basel) ; 10(3)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35334987

RESUMO

The recent emergence of a new myxoma virus capable of causing disease in the Iberian hare (Lepus granatensis) has resulted in numerous outbreaks with high mortality leading to the reduction, or even the disappearance, of many local populations of this wild species in the Iberian Peninsula. Currently, the available vaccines that prevent myxomatosis in domestic rabbits caused by classic strains of myxoma virus have not been assessed for use in Iberian hares. The main objective of this study was to evaluate the efficacy of commercial rabbit vaccines in Iberian hares and wild rabbits against the natural recombinant myxoma virus (ha-MYXV), bearing in mind its application in specific scenarios where capture is possible, such as genetic reserves. The study used a limited number of animals (pilot study), 15 Iberian hares and 10 wild rabbits. Hares were vaccinated with Mixohipra-FSA vaccine (Hipra) and Mixohipra-H vaccine (Hipra) using two different doses, and rabbits were vaccinated with the Mixohipra-H vaccine or the Nobivac Myxo-RHD PLUS (MSD Animal Health) using the recommended doses for domestic rabbits. After the vaccination trials, the animals were challenged with a wild type strain of ha-MYXV. The results showed that no protection to ha-MYXV challenge was afforded when a commercial dose of Mixohipra-FSA or Mixohipra-H vaccine was used in hares. However, the application of a higher dose of Mixohipra-FSA vaccine may induce protection and could possibly be used to counteract the accelerated decrease of wild hare populations due to ha-MYXV emergence. The two commercial vaccines (Mixohipra-H and Nobivac Myxo-RHD PLUS) tested in wild rabbits were fully protective against ha-MYXV infection. This knowledge gives more insights into ha-MYXV management in hares and rabbits and emphasises the importance of developing a vaccine capable of protecting wild populations of Iberian hare and wild rabbit towards MYXV and ha-MYXV strains.

11.
Transbound Emerg Dis ; 69(6): 3637-3650, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36219552

RESUMO

The 2018 outbreak of myxomatosis in the Iberian hare (Lepus granatensis) has been hypothesized to originate from a species jump of the rabbit-associated myxoma virus (MYXV), after natural recombination with an unknown poxvirus. Iberian hares were long considered resistant to myxomatosis as no prior outbreaks were reported. To provide insights into the emergence of this recombinant virus (ha-MYXV), we investigated serum samples from 451 Iberian hares collected over two time periods almost two decades apart, 1994-1999 and 2017-2019 for the presence of antibodies and MYXV-DNA. First, we screened all serum samples using a rabbit commercial indirect ELISA (iELISA) and then tested a subset of these samples in parallel using indirect immunofluorescence test (IFT), competitive ELISA (cELISA) and qPCR targeting M000.5L/R gene conserved in MYXV and ha-MYXV. The cut-off of iELISA relative index 10 = 6.1 was selected from a semiparametric finite mixture analysis aiming to minimize the probability of false positive results. Overall, MYXV related-antibodies were detected in 57 hares (12.6%) including 38 apparently healthy hares (n = 10, sampled in 1994-1999, none MYXV-DNA positive, and n = 28 sampled in 2017-2019 of which four were also ha-MYXV-DNA positive) and 19 found-dead and ha-MYXV-DNA-positive sampled in 2018-2019. Interestingly, four seronegative hares sampled in 1997 were MYXV-DNA positive by qPCR, the result being confirmed by sequencing of three of them. For the Iberian hares hunted or live trapped (both apparently health), seroprevalence was significantly higher in 2017-2019 (13.0%, CI95% 9.2-18.2%) than in 1994-1999 (5.4%, CI95% 3.0-9.6%) (p = .009). Within the second period, seroprevalence was significantly higher in 2019 compared to 2017 (24.7 vs 1.7% considering all the sample, p = .007), and lower during the winter than the autumn (p < .001). While our molecular and serological results show that Iberian hares have been in contact with MYXV or an antigenically similar virus at least since 1996, they also show an increase in seroprevalence in 2018-2019. The remote contact with MYXV may have occurred with strains that circulated in rabbits, or with unnoticed strains already circulating in Iberian hare populations. This work strongly suggests the infection of Iberian hares with MYXV or an antigenically related virus, at least 20 years before the severe virus outbreaks were registered in 2018.


Assuntos
Lebres , Myxoma virus , Animais , Coelhos , Estudos Retrospectivos , Estudos Soroepidemiológicos , DNA Viral , Estações do Ano , Myxoma virus/genética
12.
Transbound Emerg Dis ; 69(3): 1030-1045, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33683820

RESUMO

Rabbit haemorrhagic disease (RHD) is a major threat to domestic and wild European rabbits. Presently, in Europe, the disease is caused mainly by Rabbit haemorrhagic disease virus 2 (RHDV2/b or Lagovirus europaeus GI.2), the origin of which is still unclear, as no RHDV2 reservoir hosts were identified. After the RHDV2 emergence in 2010, viral RNA was detected in a few rodent species. Furthermore, RHDV2 was found to cause disease in some hare species resembling the disease in rabbits, evidencing the ability of the virus to cross the species barrier. In this study, through molecular, histopathologic, antigenic and morphological evidences, we demonstrate the presence and replication of RHDV2 in Eurasian badgers (Meles meles) found dead in the district of Santarém, Portugal, between March 2017 and January 2020. In these animals, we further classify the RHDV2 as a Lagovirus europaeus recombinant GI.4P-GI.2. Our results indicate that Meles meles is susceptible to RHDV2, developing systemic infection, and excreting the virus in the faeces. Given the high viral loads seen in several organs and matrices, we believe that transmission to the wild rabbit is likely. Furthermore, transmission electron microscopy data show the presence of calicivirus compatible virions in the nucleus of hepatocytes, which constitutes a paradigm shift for caliciviruses' replication cycle.


Assuntos
Infecções por Caliciviridae , Vírus da Doença Hemorrágica de Coelhos , Lagomorpha , Lagovirus , Mustelidae , Animais , Infecções por Caliciviridae/veterinária , Vírus da Doença Hemorrágica de Coelhos/genética , Filogenia , Coelhos
13.
Transbound Emerg Dis ; 68(4): 2616-2621, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33119958

RESUMO

Myxomatosis is an emergent disease in the Iberian hare, having been considered a rabbit disease for decades. Genome sequencing of the strains obtained from Iberian hares with myxomatosis showed these to be distinct from the classical ones that circulated in rabbits since the virus introduction in Europe, in 1952. The main genomic difference in this natural recombinant hare myxoma virus (ha-MYXV) is the presence of an additional 2.8 kb region disrupting the M009L gene and adding a set of genes homologous to the myxoma virus (MYXV) genes M060R, M061R, M064R, M065R and M066R originated in Poxviruses. After the emergence of this recombinant virus (ha-MYXV) in hares, in the summer of 2019, the ha-MYXV was not detected in rabbit surveys, suggesting an apparent species segregation with the MYXV classic strains persistently circulating in rabbits. Recently, a group of six unvaccinated European rabbits (Oryctolagus cuniculus cuniculus) from a backyard rabbitry in South Portugal developed signs of myxomatosis (anorexia, dyspnoea, oedema of eyelids, head, ears, external genitals and anus, and skin myxomas in the base of the ears). Five of them died within 24-48 hr of symptom onset. Molecular analysis revealed that only the recombinant MYXV was present. This is the first documented report of a recombinant hare myxoma virus in farm rabbits associated with high mortality, which increases the concern for the future of both the Iberian hare and wild rabbits and questions the safety of the rabbit industry. This highlights the urgent need to evaluate the efficacy of available vaccines against this new MYXV.


Assuntos
Myxoma virus , Mixoma , Viroses , Agricultura , Animais , Fazendas , Mixoma/veterinária , Myxoma virus/genética , Coelhos , Viroses/veterinária
14.
Viruses ; 13(4)2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33924254

RESUMO

In late 2019, the first herpesvirus in the genus Lepus, named leporid gammaherpesvirus 5 (LeHV-5) was described. At the time, herpetic typical lesions were observed in hares infected by the myxoma virus, which is known to induce immunosuppression. Though the real impact of LeHV-5 is still poorly understood, since it affects reproduction, it poses an additional threat to the already fragile populations of Iberian hare, demanding prevalence investigations. In this article, we describe the first quantitative molecular method for LeHV-5 detection, using either Taqman or the EvaGreen systems. This method has excellent sensitivity and specificity, it is able to detect 2.1 copies of LeHV-5 DNA and was validated with an internal control targeting the 18S rRNA gene, allowing monitoring extraction and PCR amplification efficiencies.


Assuntos
Gammaherpesvirinae/isolamento & purificação , Lebres/virologia , Infecções por Herpesviridae , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Infecções por Herpesviridae/diagnóstico , Infecções por Herpesviridae/veterinária
15.
Front Microbiol ; 12: 647730, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093464

RESUMO

Molecular methods, established in the 1980s, expanded and delivered tools for the detection of vestigial quantities of nucleic acids in biological samples. Nucleotide sequencing of these molecules reveals the identity of the organism it belongs to. However, the implications of such detection are often misinterpreted as pathogenic, even in the absence of corroborating clinical evidence. This is particularly significant in the field of virology where the concepts of commensalism, and other benign or neutral relationships, are still very new. In this manuscript, we review some fundamental microbiological concepts including commensalism, mutualism, pathogenicity, and infection, giving special emphasis to their application in virology, in order to clarify the difference between detection and infection. We also propose a system for the correct attribution of terminology in this context.

16.
Cells ; 10(8)2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34440869

RESUMO

Commercial hare and rabbit immortalized cell lines are extremely limited regarding the many species within the lagomorpha order. To overcome this limitation, researchers and technicians must establish primary cell cultures derived from biopsies or embryos. Among all cell types, fibroblasts are plastic and resilient cells, highly convenient for clinical and fundamental research but also for diagnosis, particularly for viral isolation. Here, we describe a fast and cheap method to produce primary fibroblast cell cultures from leporid species, using dispase II, a protease that allows dermal-epidermal separation, followed by a simple enzymatic digestion with trypsin. This method allows for the establishment of an in vitro cell culture system with an excellent viability yield and purity level higher than 85% and enables the maintenance and even immortalization of leporid fibroblastic cells derived from tissues already differentiated.


Assuntos
Fibroblastos/citologia , Cultura Primária de Células/métodos , Pele/citologia , Animais , Biomarcadores/metabolismo , Separação Celular , Sobrevivência Celular , Endopeptidases/metabolismo , Fibroblastos/metabolismo , Lagomorpha , Tripsina/metabolismo
17.
Animals (Basel) ; 11(1)2020 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-33379183

RESUMO

Rabbit haemorrhagic disease (RHD) is a highly contagious infectious disease of European wild and domestic rabbits. Rabbit haemorrhagic disease virus (RHDV, GI.1) emerged in 1986 in Europe, rapidly spreading all over the world. Several genotypes of RHDV have been recognised over time, but in 2010, a new virus (RHDV2/RHDVb, GI.2) emerged and progressively replaced the previous RHDV strains, due to the lack of cross-immunity conferred between RHDV and RHDV2. RHDV2 has a high mutation rate, similarly to the other calivirus and recombines with strains of RHDV and non-pathogenic calicivirus (GI.4), ensuring the continuous emergence of new field strains. Although this poses a threat to the already endangered European rabbit species, the available vaccines against RHDV2 and the compliance of biosafety measures seem to be controlling the infection in the rabbit industry Pet rabbits, especially when kept indoor, are considered at lower risk of infections, although RHDV2 and myxoma virus (MYXV) constitute a permanent threat due to transmission via insects. Vaccination against these viruses is therefore recommended every 6 months (myxomatosis) or annually (rabbit haemorrhagic disease). The combined immunization for myxomatosis and RHDV through a commercially available bivalent vaccine with RHDV antigen has been extensively used (Nobivac® Myxo-RHD, MSD, Kenilworth, NJ, USA). This vaccine however does not confer proper protection against the RHDV2, thus the need for a rabbit clinical vaccination protocol update. Here we report a clinical case of hepatitis and alteration of coagulation in a pet rabbit that had been vaccinated with the commercially available bivalent vaccine against RHDV and tested positive to RHDV2 after death. The animal developed a prolonged and atypical disease, compatible with RHD. The virus was identified to be an RHDV2 recombinant strain, with the structural backbone of RHDV2 (GI.2) and the non-structural genes of non-pathogenic-A1 strains (RCV-A1, GI.4). Although confirmation of the etiological agent was only made after death, the clinical signs and analytic data were very suggestive of RHD.

18.
Viruses ; 12(10)2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33028004

RESUMO

In late 2018, an epidemic myxomatosis outbreak emerged on the Iberian Peninsula leading to high mortality in Iberian hare populations. A recombinant Myxoma virus (strains MYXV-Tol and ha-MYXV) was rapidly identified, harbouring a 2.8 kbp insertion containing evolved duplicates of M060L, M061L, M064L, and M065L genes from myxoma virus (MYXV) or other Poxviruses. Since 2017, 1616 rabbits and 125 hares were tested by a qPCR directed to M000.5L/R gene, conserved in MYXV and MYXV-Tol/ha-MYXV strains. A subset of the positive samples (20%) from both species was tested for the insert with MYXV being detected in rabbits and the recombinant MYXV in hares. Recently, three wild rabbits were found dead South of mainland Portugal, showing skin oedema and pulmonary lesions that tested positive for the 2.8 kbp insert. Sequencing analysis showed 100% similarity with the insert sequences described in Iberian hares from Spain. Viral particles were observed in the lungs and eyelids of rabbits by electron microscopy, and isolation in RK13 cells attested virus infectivity. Despite that the analysis of complete genomes may predict the recombinant MYXV strains' ability to infect rabbit, routine analyses showed species segregation for the circulation of MYXV and recombinant MYXV in wild rabbit and in Iberian hares, respectively. This study demonstrates, however, that recombinant MYXV can effectively infect and cause myxomatosis in wild rabbits and domestic rabbits, raising serious concerns for the future of the Iberian wild leporids while emphasises the need for the continuous monitoring of MYXV and recombinant MYXV in both species.


Assuntos
Genoma Viral , Lebres/virologia , Myxoma virus/genética , Myxoma virus/isolamento & purificação , Coelhos/virologia , Animais , Feminino , Masculino , Mixomatose Infecciosa/patologia , Mixomatose Infecciosa/virologia , Portugal , Espanha
19.
Pest Manag Sci ; 73(7): 1438-1445, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27860205

RESUMO

BACKGROUND: The thrips Frankliniella schultzei is an important watermelon pest. Nevertheless, economic injury levels and sampling plans for this pest have not yet been determined for this crop. Thus, the objective of the present study was to determine the economic injury levels and develop sequential sampling plans for F. schultzei in conditions of low, medium and high fruit prices. RESULTS: The attack of F. schultzei on watermelon plants at the vegetative stage reduced the crop's productivity, which did not happen at the flowering and fruiting stage. The economic injury levels were 0.09, 0.04 and 0.02 thrips leaf-1 when the watermelon price was low ($US 62.5 t-1 ), medium ($US 140.63 t-1 ) and high ($US 218.75 t-1 ) respectively. The three sequential sampling plans for F. schultzei generated for the economic injury levels resulted in similar and more rapid decisions compared with the conventional plan, especially when the pest density was high. CONCLUSIONS: The three economic injury levels and the sequential sampling plans generated in the present study can be incorporated into integrated pest management programmes for watermelon crops because these plans provide a rapid and adequate control decision for F. schultzei. © 2016 Society of Chemical Industry.


Assuntos
Citrullus , Frutas/economia , Controle de Insetos/economia , Tisanópteros , Animais , Produtos Agrícolas , Controle de Insetos/métodos , Folhas de Planta
20.
Toxicon ; 42(2): 155-61, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12906886

RESUMO

The purpose of this work was to find out the cellular changes occurring in bone marrow and peripheral blood after acute exposure to the venom of Loxosceles intermedia. Doses of 40 microg of venom were injected intradermally into five rabbits, and five rabbits receiving only phosphate-buffered saline (PBS) were used as controls. Bone marrow and peripheral blood samples were obtained before the envenomation and 4, 8, 12, 24 and 48 h, and 5, 10, 15, 20 and 30 days after envenomation. In bone marrow samples we assessed cellularity, nucleated red cells, megakaryocytes and neutrophils, and in peripheral blood we assessed red cells (red cell concentration, hemoglobin and hematocrit), leukocytes, neutrophils and platelets. Our objective was to find out if the venom has a direct effect on bone marrow and peripheral blood or if changes in both of them are secondary to the needs of tissues, and if there is a good correlation between histopathological and hematological findings. We found that the red cell parameters were not affected by the venom, except for nucleated red cells which decreased after venom exposure. The depression of megakaryocyte numbers and thrombocytopenia showed a strong correlation with the histopathologic changes observed in skin biopsies obtained from the rabbits. The changes in cellularity and neutrophils of bone marrow were strongly correlated with those in peripheral blood and skin. The thrombocytopenia and neutropenia in peripheral blood are due to marrow depression, which may be a consequence of an extensive migration of platelets and neutrophils to the necrotic lesion or the marrow depression may be a transitory effect of evenoming by L. intermedia.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Diester Fosfórico Hidrolases/toxicidade , Coelhos/sangue , Venenos de Aranha/toxicidade , Aranhas/química , Animais , Plaquetas/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Leucócitos/efeitos dos fármacos , Megacariócitos/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Diester Fosfórico Hidrolases/farmacologia , Venenos de Aranha/farmacologia
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