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1.
PLoS One ; 18(5): e0286144, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37205700

RESUMO

Success of a metabarcoding study is determined by the extent of taxonomic coverage and the quality of records available in the DNA barcode reference database used. This study aimed to create an rbcL and a trnL (UAA) DNA barcode sequence reference database of plant species that are potential herbivore foraging targets and commonly found in semi-arid savannas of eastern South Africa. An area-specific species list of 765 species was compiled according to plant collection records available and areas comparable to an eastern semi-arid South African savanna. Thereafter, rbcL and trnL sequences of species from this list were mined from GenBank and BOLD sequence databases according to specific quality criteria to ensure accurate taxonomic coverage and resolution. These were supplemented with sequences of 24 species sequenced for this study. A phylogenetic approach, employing Neighbor-Joining, was used to verify the topology of the reference libraries to known angiosperm phylogeny. The taxonomic reliability of these reference libraries was evaluated by testing for the presence of a barcode gap, identifying a data-appropriate identification threshold, and determining the identification accuracy of reference sequences via primary distance-based criteria. The final rbcL reference dataset consisted of 1238 sequences representing 318 genera and 562 species. The final trnL dataset consisted of 921 sequences representing 270 genera and 461 species. Barcode gaps were found for 76% of the taxa in the rbcL barcode reference dataset and 68% of the taxa in the trnL barcode reference dataset. The identification success rate, calculated with the k-nn criterion was 85.86% for the rbcL dataset and 73.72% for the trnL dataset. The datasets for rbcL and trnL combined during this study are not presented as complete DNA reference libraries, but rather as two datasets that should be used in unison to identify plants present in the semi-arid eastern savannas of South Africa.


Assuntos
Código de Barras de DNA Taxonômico , Pradaria , África do Sul , Filogenia , Reprodutibilidade dos Testes , Plantas , DNA de Plantas/genética
2.
Nat Cell Biol ; 7(4): 429-31, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15803134

RESUMO

Although small molecules diffuse rapidly through the interphase nucleus, recent reports indicate that nuclear diffusion is limited for particles that are larger than 100 nm in diameter. Given the apparent size limits to nuclear diffusion, there is some debate as to whether the movement of large particles should be attributed to diffusion or to active transport. Here, we show that 125 nm-diameter herpes simplex virus 1 (HSV-1) capsids are actively transported within infected nuclei. Movement is directed, temperature- and energy-dependent, sensitive to the putative myosin inhibitor 2,3-butanedione monoxime (BDM) and to actin depolymerization with latrunculin-A, but insensitive to actin depolymerization with cytochalasin-D.


Assuntos
Capsídeo/fisiologia , Núcleo Celular/fisiologia , Herpesvirus Humano 1/fisiologia , Capsídeo/metabolismo , Núcleo Celular/metabolismo , Herpesvirus Humano 1/genética , Humanos , Tamanho da Partícula , Temperatura
3.
J Vet Diagn Invest ; 22(2): 299-302, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20224097

RESUMO

An 8-year-old, spayed, female Labrador Retriever mixed-breed dog was presented to the Cornell University Hospital for Animals with an invasive oral mass involving the upper left fourth premolar and first molar teeth. Initial biopsy results suggested a poorly differentiated squamous cell carcinoma, whereas further histologic examination of the surgically removed mass revealed a hemangiosarcoma-like mass composed of numerous vascular clefts and variable numbers of keratinizing epithelial cells. Histologic and immunohistochemical characteristics were compatible with pseudoangiomatous squamous cell carcinoma, a well-recognized human variant of acanthomatous squamous cell carcinoma. Because of histomorphologic similarities with canine gingival hemangiosarcoma, diagnosticians should be aware of the present tumor variant as a differential diagnosis for vascular-like growths in the oral cavity of dogs.


Assuntos
Carcinoma de Células Escamosas/veterinária , Doenças do Cão/diagnóstico , Neoplasias Bucais/veterinária , Animais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Doenças do Cão/patologia , Doenças do Cão/cirurgia , Cães , Feminino , Neoplasias Bucais/patologia , Neoplasias Bucais/cirurgia
4.
Artigo em Inglês | MEDLINE | ID: mdl-29930938

RESUMO

Pre-commercialization studies on environmental biosafety of genetically modified (GM) crops are necessary to evaluate the potential for sexual hybridization with related plant species that occur in the release area. The aim of the study was a preliminary assessment of factors that may contribute to gene flow from sugarcane (Saccharum hybrids) to indigenous relatives in the sugarcane production regions of Mpumalanga and KwaZulu-Natal provinces, South Africa. In the first instance, an assessment of Saccharum wild relatives was conducted based on existing phylogenies and literature surveys. The prevalence, spatial overlap, proximity, distribution potential, and flowering times of wild relatives in sugarcane production regions based on the above, and on herbaria records and field surveys were conducted for Imperata, Sorghum, Cleistachne, and Miscanthidium species. Eleven species were selected for spatial analyses based on their presence within the sugarcane cultivation region: four species in the Saccharinae and seven in the Sorghinae. Secondly, fragments of the nuclear internal transcribed spacer (ITS) regions of the 5.8s ribosomal gene and two chloroplast genes, ribulose-bisphosphate carboxylase (rbcL), and maturase K (matK) were sequenced or assembled from short read data to confirm relatedness between Saccharum hybrids and its wild relatives. Phylogenetic analyses of the ITS cassette showed that the closest wild relative species to commercial sugarcane were Miscanthidium capense, Miscanthidium junceum, and Narenga porphyrocoma. Sorghum was found to be more distantly related to Saccharum than previously described. Based on the phylogeny described in our study, the only species to highlight in terms of evolutionary divergence times from Saccharum are those within the genus Miscanthidium, most especially M. capense, and M. junceum which are only 3 million years divergent from Saccharum. Field assessment of pollen viability of 13 commercial sugarcane cultivars using two stains, iodine potassium iodide (IKI) and triphenyl tetrazolium chloride, showed decreasing pollen viability (from 85 to 0%) from the north to the south eastern regions of the study area. Future work will include other aspects influencing gene flow such as cytological compatibility and introgression between sugarcane and Miscanthidium species.

5.
J Am Vet Med Assoc ; 230(12): 1877-81, 2007 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-17571994

RESUMO

OBJECTIVE: To evaluate survival times and palliative effects associated with the use of samarium Sm 153 lexidronam in dogs with primary bone tumors. DESIGN: Retrospective case series. ANIMALS: 35 dogs with primary appendicular (n = 32) or axial (3) bone tumors. PROCEDURES: 1 to 4 doses of samarium Sm 153 lexidronam were administered at a rate of 37 MBq/kg (16.8 MBq/lb), IV. Response to treatment, measured by lameness improvement, and survival time were determined. RESULTS: Of the 32 dogs with appendicular tumors, 20 (63%) had an improvement in the severity of lameness 2 weeks after administration of the first dose of radioactive samarium, 8 (25%) had no change in the severity of lameness, and 4 (12%) had a worsening. Overall median survival time was 100 days, with 3 dogs (8.6%) alive after 1 year. Median survival time for the 32 dogs with appendicular tumors was 93 days, with 3 (9.4%) alive after 1 year. This was not significantly different from the median survival time of 134 days for a historical cohort of 162 dogs with appendicular osteosarcoma that underwent amputation as the only treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that samarium Sm 153 lexidronam may be useful in the palliation of pain in dogs with primary bone tumors that are not candidates for curative-intent treatment.


Assuntos
Analgésicos não Narcóticos/uso terapêutico , Doenças do Cão/tratamento farmacológico , Compostos Organometálicos/uso terapêutico , Compostos Organofosforados/uso terapêutico , Dor/tratamento farmacológico , Cuidados Paliativos/métodos , Animais , Neoplasias Ósseas/complicações , Neoplasias Ósseas/terapia , Neoplasias Ósseas/veterinária , Cães , Feminino , Masculino , Dor/etiologia , Estudos Retrospectivos , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
6.
PLoS One ; 9(2): e87585, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24503695

RESUMO

BACKGROUND: The purpose of this study was to evaluate the activity of Selective Inhibitors of Nuclear Export (SINE) compounds that inhibit the function of the nuclear export protein Exportin 1 (XPO1/CRM1) against canine tumor cell lines and perform a Phase I clinical trial of KPT-335 in dogs with spontaneous cancer to provide a preliminary assessment of biologic activity and tolerability. METHODS AND FINDINGS: Canine tumor cell lines derived from non-Hodgkin lymphoma (NHL), mast cell tumor, melanoma and osteosarcoma exhibited growth inhibition and apoptosis in response to nanomolar concentrations of SINE compounds; NHL cells were particularly sensitive with IC50 concentrations ranging from 2-42 nM. A Phase I clinical trial of KPT-335 was performed in 17 dogs with NHL (naive or relapsed), mast cell tumor or osteosarcoma. The maximum tolerated dose was 1.75 mg/kg given orally twice/week (Monday/Thursday) although biologic activity was observed at 1 mg/kg. Clinical benefit (CB) including partial response to therapy (PR, n = 2) and stable disease (SD, n = 7) was observed in 9/14 dogs with NHL with a median time to progression (TTP) for responders of 66 days (range 35-256 days). A dose expansion study was performed in 6 dogs with NHL given 1.5 mg/kg KPT-335 Monday/Wednesday/Friday; CB was observed in 4/6 dogs with a median TTP for responders of 83 days (range 35-354 days). Toxicities were primarily gastrointestinal consisting of anorexia, weight loss, vomiting and diarrhea and were manageable with supportive care, dose modulation and administration of low dose prednisone; hepatotoxicity, anorexia and weight loss were the dose limiting toxicities. CONCLUSIONS: This study provides evidence that the novel orally bioavailable XPO1 inhibitor KPT-335 is safe and exhibits activity in a relevant, spontaneous large animal model of cancer. Data from this study provides critical new information that lays the groundwork for evaluation of SINE compounds in human cancer.


Assuntos
Acrilamidas/farmacocinética , Acrilamidas/uso terapêutico , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Núcleo Celular/metabolismo , Avaliação Pré-Clínica de Medicamentos , Hidrazinas/farmacocinética , Hidrazinas/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/veterinária , Acrilamidas/administração & dosagem , Acrilamidas/efeitos adversos , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Administração Oral , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Disponibilidade Biológica , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Cães , Relação Dose-Resposta a Droga , Feminino , Humanos , Hidrazinas/administração & dosagem , Hidrazinas/efeitos adversos , Concentração Inibidora 50 , Masculino , Qualidade de Vida
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