Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 72
Filtrar
1.
Dent Mater ; 38(8): 1283-1300, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35717229

RESUMO

OBJECTIVES: To compare new bone formation in mandibular critical-sized bone defects (CSBDs) in healthy, diabetic, osteoporotic, and diabetic-osteoporotic rats filled with bioceramics (BCs) with or without bone marrow mesenchymal stem cells (BMSCs). METHODS: A total of 64 adult female Sprague-Dawley rats were randomized into four groups (n = 16 per group): Group 1 healthy, Group 2 diabetic, Group 3 osteoporotic, and Group 4 diabetic-osteoporotic rats. Streptozotocin was used to induce type 1 diabetes in Group 2 and 4, while bilateral ovariectomy was used to induce osteoporosis in Group 3 and 4. The central portion of the rat mandibular symphysis was used as a physiological CSBD. In each group, eight defects were filled with BC (hydroxypatatite 60% and ß-tricalcium phosphate 40%) alone and eight with BMSCs cultured on BC. The animals were sacrificed at 4 and 8 weeks, and the mandibles were processed for micro-computed tomography to analyze radiological union and bone mineral density (BMD); histological analysis of the bone union; and immunohistochemical analysis, which included immunoreactivity of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2). RESULTS: In all groups (healthy, diabetics, osteoporotics, and diabetics-osteoporotics), the CSBDs filled with BC + BMSCs showed greater radiological bone union, BMD, histological bone union, and more VEGF and BMP-2 positivity, in comparison with CSBDs treated with BC alone (at 4 and 8 weeks). CONCLUSIONS: Application of BMSCs cultured on BCs improves bone regeneration in CSBDs compared with application of BCs alone in healthy, diabetic, osteoporotic, and diabetic-osteoporotic rats.


Assuntos
Diabetes Mellitus , Células-Tronco Mesenquimais , Animais , Células da Medula Óssea/metabolismo , Regeneração Óssea , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patologia , Feminino , Mandíbula/metabolismo , Mandíbula/patologia , Osteogênese , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/metabolismo , Microtomografia por Raio-X
2.
Clin Oral Investig ; 26(8): 5389-5408, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35524820

RESUMO

OBJECTIVE: To compare new bone formation in mandibular symphysis critical-sized bone defects (CSBDs) in healthy and osteoporotic rats filled with bioceramics (BCs) with or without buccal fat pad mesenchymal stem cells (BFPSCs). MATERIALS AND METHODS: Thirty-two adult female Sprague-Dawley rats were randomized to two groups (n = 16 per group): group 1 healthy and group 2 osteoporotic (with bilateral ovariectomy). The central portion of the rat mandibular symphysis was used as a physiological CSBD. In each group, eight defects were filled with BC (hydroxyapatite 60% and ß-tricalcium phosphate 40%) alone and eight with BFPSCs cultured on BC. The animals were sacrificed at 4 and 8 weeks, and the mandibles were processed for micro-computed tomography to analyze radiological union and bone mineral density (BMD); histological analysis of the bone union; and immunohistochemical analysis, which included immunoreactivity of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2). RESULTS: In both groups, CSBDs filled with BC + BFPSCs showed greater radiological bone union, BMD and histological bone union, and more VEGF and BMP-2 positivity, compared with CSBDs treated with BC alone at 4 and 8 weeks. CONCLUSIONS: The application of BFPSCs cultured on BCs improves bone regeneration in CSBDs compared with BCs alone in healthy and osteoporotic rats. CLINICAL RELEVANCE: Our results may aid bone regeneration of maxillofacial CSBDs of both healthy and osteoporotic patients, but further studies are necessary.


Assuntos
Mandíbula , Fator A de Crescimento do Endotélio Vascular , Animais , Feminino , Ratos , Tecido Adiposo , Regeneração Óssea , Mandíbula/patologia , Mandíbula/cirurgia , Ratos Sprague-Dawley , Células-Tronco , Fator A de Crescimento do Endotélio Vascular/metabolismo , Microtomografia por Raio-X
3.
Anal Chim Acta ; 1141: 221-229, 2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33248656

RESUMO

Accurate measurement of naturally occurring radionuclides in blast furnace slag, a by-product of the steel industry, is required for compliance with building regulations where it is often used as an ingredient in cement. A matrix reference blast furnace slag material has been developed to support traceability in these measurements. Raw material provided by a commercial producer underwent stability and homogeneity testing, as well as characterisation of matrix constituents, to provide a final candidate reference material. The radionuclide content was then determined during a comparison exercise that included 23 laboratories from 14 countries. Participants determined the activity per unit mass for 226Ra, 232Th and 40K using a range of techniques. The consensus values obtained from the power-moderated mean of the reported participant results were used as indicative activity per unit mass values for the three radionuclides: A0(226Ra) = 106.3 (34) Bq·kg-1, A0(232Th) = 130.0 (48) Bq·kg-1 and A0(40K) = 161 (11) Bq·kg-1 (where the number in parentheses is the numerical value of the combined standard uncertainty referred to the corresponding last digits of the quoted result). This exercise helps to address the current shortage of NORM industry reference materials, putting in place infrastructure for production of further reference materials.

4.
Clin Oral Investig ; 24(4): 1479-1491, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31925587

RESUMO

OBJECTIVE: The objective is to compare new bone formation in critical defects in healthy, diabetic, and osteoporotic rats filled with hydroxyapatite (HA) alone and HA combined with simvastatin (SV). MATERIALS AND METHODS: A total of 48 adult female Sprague-Dawley rats were randomized into three groups (n = 16 per group): Group, 1 healthy; Group 2, diabetics; and Group 3, osteoporotics. Streptozotocin was used to induce type 1 diabetes in Group 2, while bilateral ovariectomy was used to induce osteoporosis in Group 3. The central portion of the rat mandibular symphysis was used as a physiological critical bone defect. In each group, eight defects were filled with HA alone and eight with HA combined with SV. The animals were sacrificed at 4 and 8 weeks, and the mandibles were processed for micro-computed tomography to analyze radiological union and bone mineral density (BMD); histological analysis of the bone union; and immunohistochemical analysis, which included immunoreactivity of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2). RESULTS: In all groups (healthy, diabetics, and osteoporotics), the defects filled with HA + SV presented greater radiological bone union, BMD, histological bone union, and more VEGF and BMP-2 positivity, in comparison with bone defects treated with HA alone. CONCLUSIONS: Combined application of HA and SV improves bone regeneration in mandibular critical bone defects compared with application of HA alone in healthy, diabetic, and osteoporotic rats. CLINICAL RELEVANCE: This study might help to patients with osteoporosis or uncontrolled diabetes type 1, but future studies should be done.


Assuntos
Regeneração Óssea , Durapatita/uso terapêutico , Mandíbula , Osteogênese , Sinvastatina/uso terapêutico , Animais , Proteína Morfogenética Óssea 2/metabolismo , Diabetes Mellitus Experimental/complicações , Feminino , Osteoporose , Ovariectomia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/metabolismo , Microtomografia por Raio-X
5.
Vet Immunol Immunopathol ; 213: 109887, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31307668

RESUMO

Chlamydia abortus produces ovine enzootic abortion (OEA). Symptoms are not observed until the organism colonises the placenta, eventually causing abortion. Infected animals become carriers and will shed the organism in the following oestruses. This process suggests that sex hormones might play an important role in the physiopathology of OEA, affecting the success of chlamydial clearance and also jeopardising the effectiveness of vaccination. However, the mechanisms through which sex hormones are involved in chlamydial pathogenicity remain unclear. The aim of this study, therefore, was to determine the effect of progesterone on the immune response against C. abortus and on the protection conferred by an experimental inactivated vaccine in sheep. Eighteen sheep were ovariectomised and divided into four groups: vaccinated and progesterone-treated (V-PG), vaccinated and non-treated (V-NT), non-vaccinated and non-treated (NV-NT) and non-vaccinated and progesterone-treated sheep (NV-PG). Animals from both PG groups were treated with commercial medroxyprogesterone acetate impregnated intravaginal sponges before and during the vaccination (V-PG) or just before challenge (NV-PG). The animals from both V groups were subcutaneously immunised with an experimental inactivated vaccine, which was seen to confer high protection in previous studies. All sheep were challenged intratracheally with C. abortus strain AB7 and were sacrificed on day 8 post-infection. Morbidity was measured as the variation in rectal temperature and samples of sera were collected for antibody and cytokine (IFN-γ and IL-10) analysis by commercial ELISA. In addition, lung and lymph node samples were collected for chlamydial detection by qPCR and for histopathological and immunohistochemical analyses. Sheep from the V-PG group showed less severe or no lesions and lower morbidity than the other groups. They also had the highest abundance of regulatory T-cells. The sheep from V-NT also manifested high antibody levels against C. abortus and less severe lesions than those observed in non-vaccinated sheep, which showed high morbidity, low antibody levels and severe lesions, especially in NV-NT. These results confirm the effectiveness of the experimental vaccine employed and suggest that progesterone could enhance the effect.


Assuntos
Vacinas Bacterianas/uso terapêutico , Infecções por Chlamydia/veterinária , Imunidade Humoral , Progesterona/administração & dosagem , Doenças dos Ovinos/imunologia , Aborto Animal/imunologia , Aborto Animal/prevenção & controle , Animais , Anticorpos Antibacterianos/sangue , Vacinas Bacterianas/imunologia , Chlamydia/imunologia , Infecções por Chlamydia/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Ovinos , Doenças dos Ovinos/microbiologia , Vacinas de Produtos Inativados/imunologia , Vacinas de Produtos Inativados/uso terapêutico
6.
Appl Radiat Isot ; 130: 162-171, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28968588

RESUMO

The indicative dose (ID) is one of the parameters established in the current European directive for water intended for human consumption. To determine the ID, it is necessary to know the activity concentration of: 238U, 234U, 226Ra, 210Po, 239,240Pu and 241Am. The existing methods to determine these radionuclides involve complex radiochemical separations (ionic exchange columns, extraction chromatography, etc.), followed by measurements with a semiconductor detector, laboratory procedures that are time-consuming and costly. As a lower cost alternative that reduces measuring and preparation times, avoids the need for a self-absorption correction and the use of tracers, and above all that can be used in any laboratory, methods based on liquid-liquid extraction and selective co-precipitation were developed. These methodologies offer high separation recovery and selectivity, and the measurements are made using a gas proportional counter or a solid ZnS(Ag) scintillation counter. The separation factor ranged between 91.4% and 100.0% for all alpha-emitting radionuclides across the different methods. The activity concentration for each method was computed through linear equations that represent the relationship between the activity and selectivity of the different alpha-emitting radionuclides. This mathematical procedure simplifies the radiochemical separations and provides more accurate activity concentrations. The results of the internal and external validation studies proved that the proposed method is suitable for determining 241Am, 226Ra, uranium, plutonium, thorium and 210Po in water samples.

7.
Dalton Trans ; 45(34): 13525-31, 2016 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-27506244

RESUMO

Methanolic reduction of [PdCl2(CH3CN)2] on a [Ni(2,5-di(1H-pyrazol-4-yl)benzenesulfonate)2] metal organic framework gives rise to Pd(2+)/Pd(0) nanocomposites with Suzuki and carbonylative Suzuki heterogeneous catalytic activities.

8.
Vet Pathol ; 51(4): 755-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24091815

RESUMO

The cadherin family of adhesion molecules regulates cell-cell interactions. N-cadherin is expressed by neural and fibroblast cells but not by normal epithelial cells. In human medicine, the role of N-cadherin in breast cancer remains controversial, but some studies have described the switch from E-cadherin to N-cadherin as a critical step in the malignant progression of neoplastic cells. The present study was carried out on 160 feline mammary tumors (21 adenomas and 139 carcinomas). The relationship between the immunohistochemical expression of N-cadherin in neoplastic epithelial cells and 2 established prognostic factors such as regional metastasis and tumor grade was examined. The results of the study showed a statistically significant relation between the expression of N-cadherin and the 2 prognostic factors, and also a reduced expression of E-cadherin in tumors that expressed N-cadherin.


Assuntos
Caderinas/metabolismo , Doenças do Gato/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Neoplasias Mamárias Animais/metabolismo , Metástase Neoplásica/patologia , Animais , Gatos , Feminino , Imuno-Histoquímica/veterinária , Gradação de Tumores/veterinária
9.
J Mater Chem B ; 2(17): 2473-2477, 2014 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32261416

RESUMO

The novel non-conventional metallodrug [(η6-p-cymene)2Ru2mitoxantronato]Cl2 (1) exhibits redox activity, DNA intercalation ability, cathepsin B and D inhibition and in vitro antitumor activity able to circumvent cisplatin resistance. Moreover, 1 can be successfully incorporated into MIL100(Fe) as a proof of concept of the feasibility of metal-organic frameworks as carriers of non-conventional drugs.

10.
Phytopathology ; 102(12): 1108-20, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23148725

RESUMO

Prunus spp. are affected by a large number of viruses, causing significant economic losses through either direct or indirect damage, which results in reduced yield and fruit quality. Among these viruses, members of the genus Ilarvirus (isometric labile ringspot viruses) occupy a significant position due to their distribution worldwide. Although symptoms caused by these types of viruses were reported early in the last century, their molecular characterization was not achieved until the 1990s, much later than for other agronomically relevant viruses. This was mainly due to the characteristic liability of virus particles in tissue extracts. In addition, ilarviruses, together with Alfalfa mosaic virus, are unique among plant viruses in that they require a few molecules of the coat protein in the inoculum in order to be infectious, a phenomenon known as genome activation. Another factor that has made the study of this group of viruses difficult is that infectious clones have been obtained only for the type member of the genus, Tobacco streak virus. Four ilarviruses, Prunus necrotic ringspot virus, Prune dwarf virus, Apple mosaic virus, and American plum line pattern virus, are pathogens of the main cultivated fruit trees. As stated in the 9th Report of the International Committee on Taxonomy of Viruses, virions of this genus are "unpromising subjects for the raising of good antisera." With the advent of molecular approaches for their detection and characterization, it has been possible to get a more precise view of their prevalence and genome organization. This review updates our knowledge on the incidence, genome organization and expression, genetic diversity, modes of transmission, and diagnosis, as well as control of this peculiar group of viruses affecting fruit trees.


Assuntos
Ilarvirus/isolamento & purificação , Doenças das Plantas/virologia , Prunus/virologia , Regulação Viral da Expressão Gênica , Genoma Viral , Ilarvirus/genética , RNA Viral/genética
11.
Vet Pathol ; 49(6): 979-87, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22337774

RESUMO

Feline mammary carcinomas are highly aggressive neoplasms. Several mechanisms are thought to be involved in their progression, including the loss of epithelial adhesion molecules. The present study was carried out on 21 adenomas and 139 mammary carcinomas. Of the carcinomas, 66 were not reported to have metastasized, while the remaining 73 had evidence of regional lymph node metastasis at the moment of diagnosis. The relationship was examined between the expression of the E-cadherin-ß-catenin complex and basal (CK5/6, CK14) and luminal (CK8/18) cytokeratin expression. In the medical literature, carcinomas expressing basal cytokeratins are reported as having a poor prognosis in human breast cancer. Results revealed that preservation of the expression of E-cadherin and ß-catenin is a significant feature of carcinomas without metastasis, whereas carcinomas with metastasis reveal the loss of one or both adhesion molecules. Additionally, basal cytokeratin expression was statistically associated with the presence of regional metastasis. Furthermore, the expression of E-cadherin-ß-catenin was significantly correlated with the high expression of CK18 and low expression of CK5/6.


Assuntos
Adenoma/veterinária , Biomarcadores Tumorais/metabolismo , Carcinoma/veterinária , Doenças do Gato/patologia , Queratinas/metabolismo , Neoplasias Mamárias Animais/patologia , Adenoma/metabolismo , Adenoma/patologia , Animais , Caderinas/metabolismo , Carcinoma/metabolismo , Carcinoma/patologia , Doenças do Gato/metabolismo , Gatos , Feminino , Imuno-Histoquímica/veterinária , Metástase Linfática , Neoplasias Mamárias Animais/metabolismo , Gradação de Tumores/veterinária , Vimentina/metabolismo , beta Catenina/metabolismo
12.
J Comp Pathol ; 145(2-3): 107-17, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21334000

RESUMO

Caprine tuberculosis is caused by bacteria of the Mycobacterium tuberculosis complex (Mycobacterium bovis and Mycobacterium caprae). Although typical tuberculoid granulomata are usually observed in the lungs and lymph nodes of infected goats, the presence of cavitary lesions with exuberant mycobacterial growth is also a common feature in this species. The aim of this study was to characterize the immunological mechanisms that lead to liquefaction and cavity formation by comparing granulomata and cavitary lesions. Samples from animals positive by skin testing were collected for microscopical and immunohistochemical examination. Samples were also collected for analysis of cytokine gene expression in the lesions by real time polymerase chain reaction. There were marked differences between granulomata and cavitary lesions. In cavitary lesions there was a substantial population of neutrophils and a significant decrease in the number of CD4(+) T cells, with concomitant increases in other T-cell populations (CD8(+) and cells expressing the γδ form of the T-cell receptor). The enzyme iNOS was strongly expressed by macrophages in the cavitary lesions. There was no difference in the balance of pro- and anti-inflammatory cytokine gene expression in the lesions. These findings suggest that cavitary lesions are reactivation sites, where conditions are optimal for Mycobacterium proliferation and that immunological mechanisms may underlie the severe destruction of lung tissue that characterizes the cavitary pathology.


Assuntos
Doenças das Cabras/imunologia , Doenças das Cabras/patologia , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/patologia , Tuberculose Pulmonar/veterinária , Animais , Expressão Gênica , Perfilação da Expressão Gênica , Cabras , Imuno-Histoquímica , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
J Comp Pathol ; 143(4): 297-302, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20466387

RESUMO

Recent research into the prevalence of Leishmania infantum infection in the Mediterranean basin points to the involvement of cats as a reservoir host, but only sporadic cases of feline leishmaniosis have been reported. Feline leishmaniosis presents primarily as cutaneous disease and diagnosis is based on the demonstration of the parasite by skin biopsy. The present report describes the microscopical changes in tissue biopsies from 15 cats with leishmaniosis. The biopsies were derived from the skin, ocular tissue and mucocutaneous junctions. The most common histopathological feature was diffuse granulomatous inflammation with macrophages containing numerous amastigotes. Other patterns included granulomatous perifolliculitis and lichenoid interface dermatitis, where there were fewer parasitized macrophages. The presence of amastigotes was confirmed by immunohistochemistry in each case. The results of the study confirm the value of histopathological and immunohistochemical techniques for the diagnosis of feline leishmaniosis.


Assuntos
Doenças do Gato/patologia , Leishmaniose/veterinária , Pele/patologia , Animais , Doenças do Gato/parasitologia , Gatos , Olho/parasitologia , Olho/patologia , Imuno-Histoquímica , Rim/parasitologia , Rim/patologia , Leishmania infantum , Leishmaniose/parasitologia , Leishmaniose/patologia , Fígado/parasitologia , Fígado/patologia , Pele/parasitologia , Baço/parasitologia , Baço/patologia
15.
Rhinology ; 48(4): 441-5, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21442082

RESUMO

OBJECTIVE: Ligation of the sphenopalatine artery is used to treat severe nasal haemorrhage. Despite the high rates of success reported, errors and complications may occur in locating the sphenopalatine foramen (SPF) through which the vasculonervous structures penetrate the nasal cavity. Thus, the objective of this study was to investigate the numerical variation of the SPF, its relation to the ethmoid bone crista of the palatine bone in the lateral nasal wall, its distance from the anterior nasal spine and the angle between this distance and the anterior nasal floor. DESIGN: Anatomical study. SETTING: Regional tertiary reference center. MATERIAL AND INTERVENTIONS: Fifty-four hemiskulls were submitted to anatomical study and measurements were made on more than 12 dissected hemiskulls using the Image Tool 3.0 software. RESULTS: The SPF was single in 87% of the specimens, and more than one orifice was present in 13%. In most specimens it was possible to establish a relation with the ethmoid crista, which is a surgical reference for the SPF location. The mean values of the measurements were significantly higher in the hemifaces than in the hemiskulls, ranging from 54 to 63 mm, and angulation ranged from 20 to 32 degrees. CONCLUSIONS: The study demonstrated that in most specimens studied the SPF was single and located in the superior nasal meatus. The distances measured suggest that these values can be used as distance references for the use of the endoscope for ligation or endonasal cauterization of the branches of the sphenopalatine artery, preventing possible errors and complications.


Assuntos
Artérias/cirurgia , Epistaxe/cirurgia , Osso Etmoide , Cavidade Nasal , Palato Duro , Osso Esfenoide , Adulto , Análise de Variância , Anatomia Transversal , Anatomia Regional/métodos , Epistaxe/patologia , Osso Etmoide/anatomia & histologia , Osso Etmoide/cirurgia , Feminino , Humanos , Citometria por Imagem , Masculino , Cavidade Nasal/irrigação sanguínea , Cavidade Nasal/patologia , Cavidade Nasal/cirurgia , Palato Duro/anatomia & histologia , Palato Duro/cirurgia , Fluxo Sanguíneo Regional , Osso Esfenoide/anatomia & histologia , Osso Esfenoide/cirurgia
16.
Vet Pathol ; 45(4): 484-8, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18587094

RESUMO

Primary pulmonary tumors are less common in dogs than secondary (metastatic) tumors. Most primary tumors are malignant and of epithelial origin. Pulmonary large-cell carcinoma is considered extremely rare in domestic animals, and some of the few reported cases actually may have been cases of malignant pulmonary histiocytosis. An 8-year-old female Wire Fox Terrier with diffuse alveolar pattern radiographically was euthanatized when it failed to respond to antibiotic therapy. Histologically, pulmonary alveolar spaces contained clusters of large round anaplastic cells with ample eosinophilic cytoplasm and large irregularly shaped nuclei with prominent nucleoli. Immunohistochemistry was used to distinguish large-cell carcinoma from malignant pulmonary histiocytosis. Tumor cells had strong immunoreactivity for cytokeratin, consistent with epithelial origin. However, a substantial percentage of the neoplastic cells co-expressed vimentin and MHC-II. The type II alveolar epithelial cell was considered the cell of origin of the neoplasm based on the presence of lamellar bodies in some neoplastic cells and immunoreactivity for surfactant protein A and thyroid transcription factor-1.


Assuntos
Carcinoma de Células Grandes/veterinária , Doenças do Cão/patologia , Neoplasias Pulmonares/veterinária , Animais , Carcinoma de Células Grandes/metabolismo , Carcinoma de Células Grandes/patologia , Doenças do Cão/metabolismo , Cães , Evolução Fatal , Feminino , Imuno-Histoquímica/veterinária , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia
17.
Arch Virol ; 153(2): 367-73, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18080796

RESUMO

Until very recently isolates of American plum line pattern virus (APLPV) had not been reported from outside North America. The nucleotide sequences corresponding to the movement (MP) and coat (CP) proteins of eight APLPV isolates from five Mediterranean countries were determined. Sequence analysis showed that both MP and CP genes are highly conserved irrespective of geographic origin. The study of the distribution of synonymous and nonsynonymous changes along both open reading frames revealed that these proteins are under the effect of negative purifying selection. The MP and CP of APLPV possess most of the functional motifs described for other members of the genus Ilarvirus.


Assuntos
Proteínas do Capsídeo/genética , Ilarvirus/classificação , Ilarvirus/genética , Doenças das Plantas/virologia , Proteínas do Movimento Viral em Plantas/genética , Sequência de Aminoácidos , Substituição de Aminoácidos , Sequência Conservada , Ilarvirus/isolamento & purificação , Região do Mediterrâneo , Dados de Sequência Molecular , Mutação , Filogenia , Polimorfismo Genético , RNA Viral/genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
18.
Plant Dis ; 92(5): 831, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-30769603

RESUMO

Tomato torrado virus (ToTV) is a recently identified Picorna-like virus that causes "torrado disease" in tomatoes (4). Typical symptoms of "torrado disease" seen in tomato crops (Solanum lycopersicum L. formerly Lycopersicon esculentum L.) were initially defined as yellow areas at the base of the leaflet that later developed into necrotic spots that sometimes abscised, leaving holes in the leaflet. Other plants showed extensive necrosis progressing from the base to the tip of the leaflet. Fruits were distorted with necrotic lines on the surface that often cracked. Affected plants had a burnt-like appearance and the production was seriously reduced. These symptoms have been observed in tomato crops in Murcia (Spain) and the Canary Islands (Spain) (1). To identify possible alternative hosts that may serve as virus reservoirs, samples of 72 different common weed species were collected in greenhouses in Murcia and the Canary Islands where "torrado disease" symptoms were observed in tomatoes. Forty-seven showed virus-like symptoms and 25 were asymptomatic. Symptoms included mild mosaic, blistering, vein clearing, interveinal yellowing, yellow spots, necrosis, leaf distortion, and curling. Samples were analyzed by one-step reverse transcription (RT)-PCR using primers specific for ToTV to amplify 580 bp of the polyprotein region of RNA2 (3) and dot-blot hybridization with a digoxygenin-labeled RNA probe complementary to the same portion of the ToTV genome. Twenty-two of the 72 weed samples belonging to Amaranthus sp. (Amaranthaceae); Spergularia sp. (Caryophyllaceae); Atriplex sp., Chenopodium ambrosioides L., Chenopodium sp., and Halogetum sativus (Loef. ex L.) Moq. (Chenopodiaceae); Senebiera didyma Pers. (Cruciferae); Malva sp. (Malvacae); Polygonum sp. (Polygonaceae); and Nicotiana glauca Graham and Solanum nigrum L. (Solanaceae) were positive for ToTV by molecular hybridization (10 samples) and RT-PCR (22 samples, including the samples positive by molecular hybridization). PCR products obtained from Atriplex sp. (Canary Islands) and S. didyma (Murcia) were sequenced (GenBank Accessions EU090252 and EU090253). BLAST analysis showed 99% identity to ToTV RNA2 sequence (GenBank Accession DQ388880). Two tomato plants were positive for ToTV by RT-PCR after mechanical back-inoculation, although no symptoms were observed. This study showed ToTV infects common weeds present in Spanish tomato crops. Recently, Trialeurodes vaporariorum has been reported to transmit ToTV (2), although the efficiency of transmission is unknown. The vector-assisted transmission of ToTV could explain the infection of weeds in affected greenhouses. To our knowledge, this is the first report of natural infection of weeds by ToTV. References: (1) A. Alfaro-Fernández et al. Plant Dis. 91:1060, 2007. (2) H. Pospieszny et al. Plant Dis. 91:1364, 2007. (3) J. Van der Heuvel et al. Plant Virus Designated Tomato Torrado Virus. Online publication. World Intellectual Property Organization WO/2006/085749, 2006. (4) M. Verbeek et al. Arch. Virol. 152:881, 2007.

19.
Vet Pathol ; 44(5): 676-82, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17846240

RESUMO

Melanomas are the most common malignant oral neoplasm in dogs. Osteocartilaginous differentiation in oral melanomas is a rare feature described both in veterinary and human medicine. Here, 10 cases of this type of neoplasm were used to study their immunohistochemical, biological, and clinical characteristics. Reactivity for S100 and melan A antigen was evaluated, and 4 prognosis factors (mitotic index, invasiveness of epithelium, nuclear atypia, and proliferation index) were analyzed and correlated with the clinical course of the neoplasms after diagnosis. Immunohistochemical analysis of the studied neoplasms, including the osteocartilaginous areas, showed positive immunoreaction for S100 and melan A, except in one dog, which was negative for melan A. Analysis of the results showed that oral melamonas with osteocartilaginous differentiation have a clinical course similar to that of other melanomas in the oral cavity. Analysis of the mitotic index and the expression of proliferation marker Ki-67 could be useful tools for predicting the biological behavior of these neoplasms.


Assuntos
Doenças do Cão/imunologia , Melanoma/veterinária , Neoplasias Bucais/veterinária , Ossificação Heterotópica/veterinária , Animais , Biomarcadores Tumorais , Doenças do Cão/diagnóstico , Doenças do Cão/patologia , Cães , Feminino , Imuno-Histoquímica , Masculino , Melanoma/diagnóstico , Melanoma/imunologia , Melanoma/patologia , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/imunologia , Neoplasias Bucais/patologia , Ossificação Heterotópica/diagnóstico , Ossificação Heterotópica/imunologia , Ossificação Heterotópica/patologia , Prognóstico
20.
J Gen Virol ; 87(Pt 8): 2371-2380, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16847133

RESUMO

Function of the melon necrotic spot virus (MNSV) genome-encoded proteins (p29, p89, p7A, p7B and p42) has been studied. Protein-expression mutants of an infectious, full-length cDNA clone of a Spanish MNSV-Al isolate and a recombinant green fluorescent protein (GFP)-expressing virus were used in infection bioassays on melon plants. Results revealed that p29 and p89 are both essential for virus replication, whereas small proteins p7A and p7B are sufficient to support viral movement between adjacent cells operating in trans. It is also demonstrated that, in addition to its structural role as coat protein, p42 is an important factor controlling symptoms and is required for systemic transport. Moreover, both p42 and p7B, among all of the MNSV-encoded proteins, were able to delay RNA silencing in transient-expression assays on GFP-transgenic Nicotiana benthamiana plants. Finally, the presence of p42 also produced an enhancing effect on local spread similar to that of potyviral helper component proteinase (HC-Pro), probably due to its RNA silencing-suppression ability.


Assuntos
Carmovirus/fisiologia , Proteínas Virais/fisiologia , Carmovirus/genética , Cucurbitaceae/virologia , Genes Reporter , Proteínas de Fluorescência Verde/análise , Proteínas de Fluorescência Verde/genética , Microscopia Confocal , Mutação , Doenças das Plantas/virologia , Folhas de Planta/virologia , Proteínas do Movimento Viral em Plantas , Interferência de RNA , Coloração e Rotulagem/métodos , Proteínas Virais/genética , Replicação Viral/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA