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1.
J Cutan Pathol ; 42(10): 674-92, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26156537

RESUMO

BACKGROUND: Chronic cutaneous borreliosis (acrodermatitis chronica atrophicans, ACA) is a relatively rare manifestation of borreliosis attributed mainly to Borrelia afzelii. Chronic borreliosis has been associated with ospA and ospC genotypes. Literature on molecular investigations of Borrelia in lesions of ACA is scant. METHODS: Histopathological and immmunohistochemical features in 22 biopsies of ACA (16 patients) were examined. Paraffin-embedded biopsies were analyzed with polymerase chain reaction (PCR) assays targeting ospA and ospC genes, sequencing and phylogenetic analysis. RESULTS: Genotyping of ospA identified B. afzelii, serotype 2, in 12 of 16 patients. ospC-PCR was positive in seven patients revealing genotypes Af5 (n = 4), Af2 (n = 2) and Af6 (n = 1). Histopathologically, interstitial granulomatous infiltrates (CD68 positive) were common, combined with thickened collagen bundles and band-like infiltrates of CD4 positive T lymphocytes. Plasma cells were sparse/absent in 9 of 22 specimens even on staining with CD138. On CD34-staining, interstitial fibroblasts were often reduced akin to the situation in morphea. CONCLUSIONS: With assays targeting ospA and ospC genes we confirmed from paraffin-embedded biopsies that B. afzelii, serotype 2, osp C groups Af5, Af2 and Af6 is the main cause of ACA. Specimens commonly showed a combination of band-like T-cell-rich infiltrates with interstitial granulomatous features, a pattern previously under-recognized in ACA. This finding was particularly typical for lesions infected with ospC genotype Af5.


Assuntos
Acrodermatite/imunologia , Acrodermatite/microbiologia , Antígenos de Bactérias/genética , Antígenos de Superfície/genética , Proteínas da Membrana Bacteriana Externa/genética , Vacinas Bacterianas/genética , Infecções por Borrelia/imunologia , Infecções por Borrelia/microbiologia , Grupo Borrelia Burgdorferi/genética , Lipoproteínas/genética , Acrodermatite/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções por Borrelia/patologia , Feminino , Granuloma/imunologia , Granuloma/microbiologia , Granuloma/patologia , Humanos , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Plasmócitos/imunologia , Plasmócitos/patologia , Reação em Cadeia da Polimerase/métodos , Linfócitos T/imunologia , Linfócitos T/patologia
2.
J Biol Chem ; 286(5): 3185-93, 2011 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-21118803

RESUMO

Most hemoglobins serve for the transport or storage of O(2). Although hemoglobins are widespread in "entomostracan" Crustacea, malacostracans harbor the copper-containing hemocyanin in their hemolymph. Usually, only one type of respiratory protein occurs within a single species. Here, we report the identification of a hemoglobin of the shore crab Carcinus maenas (Malacostraca, Brachyura). In contrast to the dodecameric hemocyanin of this species, C. maenas hemoglobin does not reside in the hemolymph but is restricted to the gills. Immunofluorescence studies and cell fractioning showed that C. maenas hemoglobin resides in the membrane of the chief cells of the gill. To the best of our knowledge, this is the first time that a membrane-bound hemoglobin has been identified in eukaryotes. Bioinformatic evaluation suggests that C. maenas hemoglobin is anchored in the membrane by N-myristoylation. Recombinant C. maenas hemoglobin has a hexacoordinate binding scheme at the Fe(2+) and an oxygen affinity of P(50) = 0.5 Torr. A rapid autoxidation rate precludes a function as oxygen carrier. We rather speculate that, analogous to prokaryotic membrane-globins, C. maenas hemoglobin carries out enzymatic functions to protect the lipids in cell membrane from reactive oxygen species. Sequence comparisons and phylogenetic studies suggested that the ancestral arthropod hemoglobin was most likely an N-myristoylated protein that did not have an O(2) supply function. True respiratory hemoglobins of arthropods, however, evolved independently in chironomid midges and branchiopod crustaceans.


Assuntos
Braquiúros/fisiologia , Animais , Braquiúros/química , Brânquias , Hemoglobinas , Proteínas de Membrana , Dados de Sequência Molecular , Oxigênio/metabolismo , Distribuição Tecidual
3.
Mol Biol Evol ; 26(12): 2711-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19692666

RESUMO

The Remipedia are enigmatic crustaceans from anchialine cave systems, first described only 30 years ago, whose phylogenetic affinities are as yet unresolved. Here we report the sequence of hemocyanin from Speleonectes tulumensis Yager, 1987 (Remipedia, Speleonectidae). This is the first proof of the presence of this type of respiratory protein in a crustacean taxon other than Malacostraca. Speleonectes tulumensis hemocyanin consists of multiple distinct (at least three) subunits (StuHc1-3; Hc, hemocyanin). Surprisingly, the sequences are most similar to hexapod hemocyanins. Phylogenetic analyses showed that the S. tulumensis hemocyanin subunits StuHc1 and StuHc3 associate with the type 1 hexapod hemocyanin subunits, whereas StuHc2 associates with the type 2 subunits of hexapods. Together, remipede and hexapod hemocyanins are in the sister-group position to the hemocyanins of malacostracan crustaceans. Hemocyanins provide no indication of a close relationship of Myriapoda and Hexapoda but support Pancrustacea (Crustacea + Hexapoda). Our results also suggest that Crustacea are paraphyletic and that Hexapoda may have evolved from a Remipedia-like ancestor. Thus, Remipedia occupy a key position for the understanding of the evolution of hexapods, which are and have been one of the world's most speciose lineage of animals.


Assuntos
Crustáceos/classificação , Crustáceos/genética , Hemocianinas/química , Filogenia , Sequência de Aminoácidos , Animais , Teorema de Bayes , Hemocianinas/genética , Proteínas de Insetos/genética , Dados de Sequência Molecular , Consumo de Oxigênio/genética , Subunidades Proteicas/química , Subunidades Proteicas/genética
4.
JNCI Cancer Spectr ; 2(3): pky032, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31360859

RESUMO

BACKGROUND: Current clinico-pathological American Joint Committee on Cancer (AJCC) staging of primary cutaneous melanoma is limited in its ability to determine clinical outcome, and complementary biomarkers are not available for routine prognostic assessment. We therefore adapted a gene signature, previously identified in fresh-frozen (FF) melanomas and adjacent stroma, to formalin-fixed paraffin-embedded (FFPE) melanomas. The aim was to develop a gene expression profiling (GEP) score to define patient survival probability at the time of first diagnosis. METHODS: Expression of 11 FF melanoma signature genes was quantified by reverse transcription polymerase chain reaction in an FFPE melanoma training cohort (n = 125), corresponding to the combined FF melanoma training and validation cohorts. The resulting GEP score was validated technically and clinically in an independent FFPE melanoma cohort (n = 211). All statistical tests were two-sided. RESULTS: We identified a prognostic eight-gene signature in the tumor area (tumor and adjacent tissue) of AJCC stage I-III melanomas. A signature-based GEP score correlated with melanoma-specific survival (MSS; Kaplan-Meier analysis: P < .0001) was independent of tumor stage (multivariable regression analysis: P = .0032) and stroma content (<5%-90%) and complemented conventional AJCC staging (receiver operating characteristic curve analysis: area under the curve = 0.91). In the clinical validation cohort, the GEP score remained statistically significant (P = .0131) in a multivariable analysis accounting for conventional staging. The GEP score was technically robust (reproducibility: 93%; n = 84) and clinically useful, as a binary as well as a continuous score, in predicting stage-specific patient MSS. CONCLUSIONS: The GEP score is a clinically significant prognostic tool, contributes additional information regarding the MSS of melanoma patients, and complements conventional staging.

6.
J Comp Physiol B ; 180(8): 1235-45, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20640429

RESUMO

Hemocyanin is the blue respiratory protein of many arthropod species. While its structure, evolution, and physiological function have been studied in detail in Decapoda, there is little information on hemocyanins from other crustacean taxa. Here, we have investigated the hemocyanin of the peacock mantis shrimp Odontodactylus scyllarus, which belongs to the Stomatopoda (Hoplocarida). O. scyllarus hemocyanin forms a dodecamer (2 × 6-mer), which is composed of at least four distinct subunit types. We obtained the full-length cDNA sequences of three hemocyanin subunits, while a fourth cDNA was incomplete at its 5' end. The complete full-length cDNAs of O. scyllarus hemocyanin translate into polypeptides of 650-662 amino acids, which include signal peptides of 16 or 17 amino acids. The predicted molecular masses of 73.1-75.1 kDa correspond well with the main hemolymph proteins detected by SDS-PAGE and Western blotting using various anti-hemocyanin antibodies. Phylogenetic analyses show that O. scyllarus hemocyanins belong to the ß-type of malacostracan hemocyanin subunits, which diverged from the other subunits before the radiation of the malacostracan subclasses around 520 million years ago. Molecular clock analysis revealed an ancient and complex pattern of hemocyanin subunit evolution in Malacostraca and also allowed dating divergence times of malacostracan taxa.


Assuntos
Crustáceos/genética , Hemocianinas/química , Sequência de Aminoácidos , Animais , Evolução Molecular , Hemocianinas/genética , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência
7.
J Exp Biol ; 210(Pt 20): 3636-43, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17921165

RESUMO

The chitin portion of the peritrophic matrix in the midgut of the tobacco hornworm, Manduca sexta, is produced by chitin synthase 2 (CHS2), a transmembrane family II glycosyltransferase, located at the apical tips of brush border microvilli. To look for proteins that potentially interact with CHS2, we performed yeast two-hybrid screening, identifying a novel chymotrypsin-like protease (CTLP1) that binds to the extracellular carboxyterminal domain of CHS2. The occurrence of this interaction in vivo is supported by co-localization and co-immunoprecipitation data. Based on our findings we propose that chitin synthesis is controlled by an intestinal proteolytic signalling cascade linking chitin synthase activity to the nutritional state of the larvae.


Assuntos
Quitina Sintase/metabolismo , Quimases/metabolismo , Sistema Digestório/enzimologia , Manduca/enzimologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Quitina/biossíntese , Quitina Sintase/química , Quitina Sintase/genética , Quimases/química , Quimases/genética , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Sistema Digestório/citologia , Regulação Enzimológica da Expressão Gênica , Imuno-Histoquímica , Imunoprecipitação , Manduca/citologia , Manduca/genética , Dados de Sequência Molecular , Ligação Proteica , Estrutura Terciária de Proteína , Transporte Proteico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sequência de DNA , Técnicas do Sistema de Duplo-Híbrido
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