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1.
Infect Agent Cancer ; 12: 51, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29034001

RESUMO

[This corrects the article DOI: 10.1186/s13027-017-0135-8.].

2.
Am J Bot ; 102(11): 1883-900, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26542845

RESUMO

PREMISE OF THE STUDY: Mosses, very diverse in modern ecosystems, are currently underrepresented in the fossil record. For the pre-Cenozoic, fossil mosses are known almost exclusively from compression fossils, while anatomical preservation, which is much more taxonomically informative, is rare. The Lower Cretaceous of Vancouver Island (British Columbia, Canada) hosts a diverse anatomically preserved flora at Apple Bay. While the vascular plant component of the Apple Bay flora has received much attention, the numerous bryophytes identified at the locality have yet to be characterized. METHODS: Fossil moss gametophytes in more than 20 carbonate concretions collected from the Apple Bay locality on Vancouver Island were studied in serial sections prepared using the cellulose acetate peel technique. KEY RESULTS: We describe Tricosta plicata gen. et sp. nov., a pleurocarpous moss with much-branched gametophytes, tricostate plicate leaves, rhizoid-bearing bases, and delicate gametangia (antheridia and archegonia) borne on specialized branches. A new family of hypnanaean mosses, Tricostaceae fam. nov., is recognized based on the novel combination of characters of T. plicata. CONCLUSIONS: Tricosta plicata reveals pleurocarpous moss diversity unaccounted for in extant floras. This new moss adds the first bryophyte component to an already diverse assemblage of vascular plants described from the Early Cretaceous at Apple Bay and, as the oldest representative of the Hypnanae, provides a hard minimum age for the group (136 Ma).


Assuntos
Briófitas/classificação , Evolução Biológica , Colúmbia Britânica , Briófitas/citologia , Briófitas/genética , Fósseis , Células Germinativas Vegetais/classificação , Células Germinativas Vegetais/citologia , Ilhas , Folhas de Planta/classificação , Folhas de Planta/citologia , Folhas de Planta/genética , Brotos de Planta/classificação , Brotos de Planta/citologia , Brotos de Planta/genética
3.
Br J Cancer ; 101(8): 1351-6, 2009 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-19773762

RESUMO

BACKGROUND: High-risk human papilloma viruses (HPVs) are candidates as causal viruses in breast cancer. The scientific challenge is to determine whether HPVs are causal and not merely passengers or parasites. Studies of HPV-related koilocytes in breast cancer offer an opportunity to address this crucial issue. Koilocytes are epithelial cells characterised by perinuclear haloes surrounding condensed nuclei and are commonly present in cervical intraepithelial neoplasia. Koilocytosis is accepted as pathognomonic (characteristic of a particular disease) of HPV infection. The aim of this investigation is to determine whether putative koilocytes in normal and malignant breast tissues are because of HPV infection. METHODS: Archival formalin-fixed normal and malignant breast specimens were investigated by histology, in situ PCR with confirmation of the findings by standard PCR and sequencing of the products, plus immunohistochemistry to identify HPV E6 oncoproteins. RESULTS: human papilloma virus-associated koilocytes were present in normal breast skin and lobules and in the breast skin and cancer tissue of patients with ductal carcinoma in situ (DCIS) and invasive ductal carcinomas (IDCs). INTERPRETATION: As koilocytes are known to be the precursors of some HPV-associated cervical cancer, it follows that HPVs may be causally associated with breast cancer.


Assuntos
Neoplasias da Mama/etiologia , Células Epiteliais/patologia , Papillomaviridae/isolamento & purificação , Lesões Pré-Cancerosas/etiologia , Mama/virologia , Neoplasias da Mama/patologia , Neoplasias da Mama/virologia , Feminino , Humanos , Carga Viral
4.
Br J Cancer ; 101(8): 1345-50, 2009 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-19724278

RESUMO

BACKGROUND: There is increasing evidence that high-risk human papilloma virus (HPV) is involved in cancers in addition to cervical cancer. For example, it is generally accepted that HPV has a role in a significant proportion of head and neck tumours, and it has long been hypothesised that hormone dependent oncogenic viruses, such as HPV may have causal roles in some human breast cancers. A number of reports have identified HPV DNA in breast tissue and breast cancer specimens, but these rely on standard polymerase chain reaction (PCR), which is criticised for its propensity for contamination. METHODS: We have used two different technologies, in situ and standard PCR (with sequencing), and histology based on light microscopy. RESULTS: We unambiguously demonstrate the presence of high-risk HPV in the cells of breast cancer specimens and breast cancer cell lines. In addition, we also show that the oncogenic characteristics of HPV associated breast cancer are very similar to HPV-associated cervical cancer. Specifically, that putative koilocytes are present in some HPV associated breast cancers. INTERPRETATION: The above observations indicate a likely causal role for high-risk HPV in human breast cancer and offer the possibility of primary prevention of some breast cancers by vaccination against HPV.


Assuntos
Neoplasias da Mama/virologia , Papillomaviridae/isolamento & purificação , Sequência de Bases , Neoplasias da Mama/etiologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , DNA Viral/análise , Feminino , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
5.
J Mol Evol ; 39(1): 47-55, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8064872

RESUMO

Three pairs of oligonucleotide primers based on partial DNA and amino acid sequences were used in a combination of PCR experiments to amplify the beta-globin gene of the bivalve mollusc Anadara trapezia. The sequence of 2,139 bp presented contains the whole of the beta-globin gene with the exception of the 5' flanking sequence. This gene possesses the three-exon-and-two-intron gene structure typical of vertebrate globin genes but the lengths of the introns (762 bp and 690 bp, respectively) are only approximately half the size of those present in a beta-variant gene previously characterized from this organism. The encoded amino acid sequence shows two changes when compared to the previously published amino acid sequence.


Assuntos
Evolução Biológica , Globinas/genética , Invertebrados/genética , Moluscos/genética , Vertebrados/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA/análise , Primers do DNA , Éxons , Variação Genética , Íntrons , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/métodos , Mapeamento por Restrição
6.
Biochim Biophys Acta ; 1089(1): 61-7, 1991 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-2025649

RESUMO

A minor haemoglobin gene was isolated from an Anadara trapezia genomic library using a synthetic oligonucleotide probe based on the identical amino acid sequence of the F-helical region of all the major Anadara globins previously sequenced. The amino acid sequence inferred from the coding region of the gene indicated that it is different from that of the three major chains alpha, beta and gamma, but most like the beta-chain. This beta-variant sequence shows 100% homology in the conserved F-helix region. The minor gene was found to contain two long intervening sequences, 1214 bp and 1435 bp, longer than those present in the genes for vertebrate globins or leghaemoglobins but shorter than those in myoglobin genes.


Assuntos
Bivalves/genética , Globinas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Biblioteca Genômica , Dados de Sequência Molecular , Sondas de Oligonucleotídeos
7.
Aust J Biol Sci ; 41(4): 507-16, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3271383

RESUMO

The female sex hormone, oestrogen, plays a central role in breast cell proliferation in both the normal and malignant state. It controls transcription from several genes, including that for the progesterone receptor, and in endometrial tissue, via this receptor, it controls the gene for the enzyme oestrogen sulfotransferase. This enzyme may control the level of the oestrogen receptor by sulfurylating free oestradiol. To study the mode of transcriptional control exercised by oestrogen, bovine oestrogen sulfotransferase cDNA has been cloned and the nucleotide sequence determined. The message, of which 1812 bases have been sequenced, contains an open reading frame of 885 bases which encode a protein of 295 amino acids and a maximum apparent molecular weight of 34,600. The deduced protein sequence is supported by existing peptide sequence data and appears to contain a steroid-binding region. Some physico-chemical characteristics of the enzyme appear to differ markedly from those previously reported.


Assuntos
Clonagem Molecular , DNA/genética , Placenta/enzimologia , Sulfotransferases , Sulfurtransferases/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Bovinos , Códon , Sondas de DNA , Feminino , Humanos , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Gravidez , Homologia de Sequência do Ácido Nucleico
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