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1.
ESMO Open ; 8(3): 101572, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37270871

RESUMO

PURPOSE: Platinum-fluoropyrimidine combinations are standard of care for treatment of metastatic esophagogastric adenocarcinoma. The optimal duration of first-line chemotherapy is unknown, however, and maintenance strategies have not yet been established. DESIGN: MATEO is an international randomized phase II trial exploring efficacy and safety of S-1 maintenance therapy in human epidermal growth factor receptor 2 (HER2)-negative advanced esophagogastric adenocarcinoma. After 3 months of first-line platinum-fluoropyrimidine-based induction therapy, patients without progression were randomized in a 2 : 1 allocation to receive S-1 monotherapy (arm A) or to continue combination chemotherapy (arm B). The primary objective was to show non-inferiority of overall survival in the S-1 maintenance group. Progression-free survival, adverse events, and quality of life were secondary endpoints. RESULTS: From 2014 to 2019, 110 and 55 patients were randomized in arm A and arm B, respectively (recruitment closed prematurely). Median overall survival from randomization was 13.4 months for arm A and 11.4 months for arm B [hazard ratio 0.97 (80% confidence interval 0.76-1.23), P = 0.86]. Median progression-free survival from randomization was 4.3 and 6.1 months for arm A versus arm B, respectively [hazard ratio 1.10 (80% confidence interval 0.86-1.39), P = 0.62]. Patients in arm A had numerically fewer treatment-related adverse events (84.9% versus 93.9%) and significantly less peripheral sensory polyneuropathy ≥grade 2 (9.4% versus 36.7%). CONCLUSIONS: S-1 maintenance following platinum-based induction therapy leads to non-inferior survival outcomes compared with the continuation of platinum-based combination. Toxicity patterns favor a fluoropyrimidine maintenance strategy. These data challenge the continued use of platinum combination chemotherapy after response to 3 months induction therapy in patients with advanced human epidermal growth factor receptor 2-negative esophagogastric adenocarcinoma.


Assuntos
Adenocarcinoma , Qualidade de Vida , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Intervalo Livre de Progressão , Adenocarcinoma/patologia
3.
Chirurg ; 92(6): 499-505, 2021 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-33566116

RESUMO

According to current German and European clinical practice guidelines perioperative chemotherapy is the recommended standard of care for localized gastric cancer beyond early cancers, i.e. in stage IB (T2 N0 M0 and T1 N1 M0) or greater. For patients who are able to tolerate intensive chemotherapy, the FLOT regimen (5-fluorouracil, folinic acid, oxaliplatin, docetaxel) should be administered preoperatively and postoperatively for four cycles each. Locally advanced nonmetastatic adenocarcinoma of the esophagogastric junction (AEG) should be treated with perioperative chemotherapy as for gastric cancer or alternatively with neoadjuvant chemoradiotherapy. The best approach for AEG is currently being investigated in ongoing clinical trials. The recommendation of perioperative treatment applies to all histopathological subtypes of gastric cancer. The article summarizes the contemporary data and provides an outlook on current progress in the field of medicinal perioperative treatment.


Assuntos
Neoplasias Esofágicas , Neoplasias Gástricas , Protocolos de Quimioterapia Combinada Antineoplásica , Biomarcadores , Neoplasias Esofágicas/tratamento farmacológico , Junção Esofagogástrica/cirurgia , Fluoruracila/uso terapêutico , Humanos , Terapia Neoadjuvante , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/cirurgia
4.
Sci Rep ; 10(1): 22410, 2020 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-33376252

RESUMO

Replant disease is a worldwide phenomenon affecting various woody plant genera and species, especially within the Rosaceae. Compared to decades of intensive studies regarding replant disease of apple (ARD), the replant disease of roses (RRD) has hardly been investigated. The etiology of RRD is also still unclear and a remedy desperately needed. In greenhouse pot trials with seedlings of the RRD-sensitive rootstock Rosa corymbifera 'Laxa' cultured in replant disease affected soils from two different locations, early RRD symptom development was studied in fine roots. In microscopic analyses we found similarities to ARD symptoms with regards to structural damages, impairment in the root hair status, and necroses and blackening in the cortex tissue. Examinations of both whole mounts and thin sections of fine root segments revealed frequent conspicuous fungal infections in association with the cellular disorders. Particularly striking were fungal intracellular structures with pathogenic characteristics that are described for the first time. Isolated fungi from these tissue areas were identified by means of ITS primers, and many of them were members of the Nectriaceae. In a next step, 35 of these isolates were subjected to a multi-locus sequence analysis and the results revealed that several genera and species were involved in the development of RRD within a single rose plant. Inoculations with selected single isolates (Rugonectria rugulosa and Ilyonectria robusta) in a Perlite assay confirmed their pathogenic relationship to early necrotic host plant reactions, and symptoms were similar to those exhibited in ARD.


Assuntos
Hypocreales/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Raízes de Plantas , Rosa , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Rosa/metabolismo , Rosa/microbiologia
5.
Hortic Res ; 7: 144, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922816

RESUMO

Growth depression of Rosa plants at sites previously used to cultivate the same or closely related species is a typical symptom of rose replant disease (RRD). Currently, limited information is available on the causes and the etiology of RRD compared to apple replant disease (ARD). Thus, this study aimed at analyzing growth characteristics, root morphology, and root metabolites, as well as microbial communities in the rhizosphere of the susceptible rootstock Rosacorymbifera 'Laxa' grown in RRD-affected soil from two sites (Heidgraben and Sangerhausen), either untreated or disinfected by γ-irradiation. In a greenhouse bioassay, plants developed significantly more biomass in the γ-irradiated than in the untreated soils of both sites. Several plant metabolites detected in R. corymbifera 'Laxa' roots were site- and treatment-dependent. Although aloesin was recorded in significantly higher concentrations in untreated than in γ-irradiated soils from Heidgraben, the concentrations of phenylalanine were significantly lower in roots from untreated soil of both sites. Rhizosphere microbial communities of 8-week-old plants were studied by sequencing of 16S rRNA, ITS, and cox gene fragments amplified from total community DNA. Supported by microscopic observations, sequences affiliated to the bacterial genus Streptomyces and the fungal genus Nectria were identified as potential causal agents of RRD in the soils investigated. The relative abundance of oomycetes belonging to the genus Pythiogeton showed a negative correlation to the growth of the plants. Overall, the RRD symptoms, the effects of soil treatments on the composition of the rhizosphere microbial community revealed striking similarities to findings related to ARD.

6.
Zootaxa ; 4162(1): 173-87, 2016 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-27615965

RESUMO

A new species of burrowing crayfish, Cambarus (Jugicambarus) adustus, is described from Lewis County in northeastern Kentucky, USA. The new species is most similar morphologically to C. dubius. Cambarus adustus coloration differs from C. dubius by lacking red, orange and blue hues, and instead is brown over the entire body surface. Morphological differences between C. dubius and C. adustus exist in the form I male gonopod, with C. adustus possessing a caudal knob, while C. dubius does not. In addition, the lateral carapace of C. adustus is distinctly tuberculate, whereas in C. dubius the carapace lacks extensive tuberculation. Cambarus (J.) adustus appears to have an extremely small geographic range (~19.5 km2), and as such we suggest its consideration for both state and federal levels of protection.


Assuntos
Astacoidea/anatomia & histologia , Astacoidea/classificação , Distribuição Animal/fisiologia , Animais , Astacoidea/genética , Astacoidea/fisiologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Kentucky , Masculino , Filogenia , Especificidade da Espécie
7.
Zootaxa ; 3980(4): 526-46, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-26249970

RESUMO

Cambarus (Jugicambarus) dubius Faxon, 1884 is a polychromatic montane burrowing crayfish with a long, turbulent taxonomic history since its original description by Walter Faxon in 1884. Over the years, many distinct color phases have been identified, with the majority of these being confined to a specific geographic or physiographic region in the central and southern Appalachians. Previous investigations of this species (e.g., Dewees 1972) were unable to discover consistent morphological differences among the various groups, and thus were unable to clarify what has long been considered a species complex. Due to lingering taxonomic issues, we herein re-describe, delimit and restrict the concept of C. dubius. We also describe a new species, Cambarus (Jugicambarus) pauleyi, from the same complex, which can be identified through the use of geographic distribution, coloration, and distinct morphological characters. Cambarus dubius sensu stricto, as defined here, is restricted to the "typical form" which has an overall orang-ish color pattern on the dorsal and lateral sides, with cream ventrally. The distribution of C. dubius s.s. is limited to the central and northern portions of the Allegheny Mountains and high elevations of the Appalachian Plateau in central West Virginia, western Maryland, and southcentral Pennsylvania. In contrast, C. pauleyi is endemic to high elevation wetlands (>700 m) in the Meadow and Greenbrier River basins in Greenbrier and Monroe counties, West Virginia. Cambarus pauleyi can be differentiated from C. dubius s.s. by 1) its blue dorsal coloration compared to the orange coloration of C. dubius s.s., 2) its large (palm depth/(palm length) ratio, and 3) its smaller (rostral width)/(rostral length) ratio. Cambarus pauleyi can be separated from other peripatric populations of C. dubius sensu lato that occur in the Meadow and Greenbrier River drainage by its 1) blue coloration compared to the orange and black coloration of the latter, 2) the smaller (palm depth)/(palm length) ratio in C. pauleyi, and 3) the deeply excavated rostrum of C. dubius compared to the moderately excavated rostrum of C. pauleyi. Cambarus pauleyi can be easily differentiated from both taxa by the presence of two subpalmer tubercles. Both C. dubius s.s and peripatric C. dubius lack subpalmer tubercles. Cambarus pauleyi has an extremely narrow geographic distribution and has possibly experienced a significant range reduction due to the conversion of wetlands into pastures, and should be considered "Endangered" according to American Fisheries Society listing criteria (Taylor et al. 2007).


Assuntos
Astacoidea/anatomia & histologia , Astacoidea/classificação , Animais , Feminino , Masculino , West Virginia
8.
Bioinformatics ; 21 Suppl 2: ii130-6, 2005 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16204092

RESUMO

MOTIVATION: With cDNA or oligonucleotide chips, gene-expression levels of essentially all genes in a genome can be simultaneously monitored over a time-course or under different experimental conditions. After proper normalization of the data, genes are often classified into co-expressed classes (clusters) to identify subgroups of genes that share common regulatory elements, a common function or a common cellular origin. With most methods, e.g. k-means, the number of clusters needs to be specified in advance; results depend strongly on this choice. Even with likelihood-based methods, estimation of this number is difficult. Furthermore, missing values often cause problems and lead to the loss of data. RESULTS: We propose a fully probabilistic Bayesian model to cluster gene-expression profiles. The number of classes does not need to be specified in advance; instead it is adjusted dynamically using a Reversible Jump Markov Chain Monte Carlo sampler. Imputation of missing values is integrated into the model. With simulations, we determined the speed of convergence of the sampler as well as the accuracy of the inferred variables. Results were compared with the widely used k-means algorithm. With our method, biologically related co-expressed genes could be identified in a yeast transcriptome dataset, even when some values were missing. AVAILABILITY: The code is available at http://genome.tugraz.at/BayesianClustering/


Assuntos
Algoritmos , Análise por Conglomerados , Perfilação da Expressão Gênica/métodos , Modelos Genéticos , Família Multigênica/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Reconhecimento Automatizado de Padrão/métodos , Inteligência Artificial , Teorema de Bayes , Simulação por Computador
9.
Biochem J ; 344 Pt 3: 937-43, 1999 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-10585884

RESUMO

Heparan sulphate proteoglycans and the extracellular matrix of bone-marrow-stromal cells are important components of the microenvironment of haematopoietic tissues and are involved in the interaction of haematopoietic stem and stromal cells. Previous studies have emphasized the role of heparan sulphate proteoglycan synthesis by bone-marrow-stromal cells. In the present study we describe the expression of glypican-4 (GPC-4), belonging to the glypican family, in bone-marrow-stromal cells and haematopoietic-progenitor cells of human and murine origin. Expression of GPC-4 was shown on the mRNA-level by reverse transcription-PCR and Northern blot analysis. Amplification products were cloned and sequenced, to confirm these results. To analyze the expression of GPC-4 on the protein level, polyclonal antibodies against selected peptides were raised in rabbits. Western blot analysis showed expression of GPC-4 as a heparan sulphate proteoglycan in the human haematopoietic-progenitor cell line TF-1 and normal human bone marrow. These results were confirmed by FACS analysis of TF-1 cells. Furthermore, GPC-4-positive progenitor cells and stromal cells were enriched from normal human bone marrow by magnetic-cell sorting and analysed by confocal laser-scanning microscopy.


Assuntos
Células da Medula Óssea/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Proteoglicanas de Heparan Sulfato/genética , Sequência de Aminoácidos , Animais , Western Blotting , Clonagem Molecular , Citometria de Fluxo , Glipicanas , Hematopoese , Proteoglicanas de Heparan Sulfato/metabolismo , Humanos , Imuno-Histoquímica , Camundongos , Microscopia Confocal , Dados de Sequência Molecular , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Estromais/metabolismo
10.
Anticancer Res ; 19(4A): 2633-6, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10470208

RESUMO

INTRODUCTION: The number of assays available for the measurement of total and free PSA is increasing. As different methods can determine different PSA concentrations as well as different free-to-total PSA ratios in identical serum samples, the cut-offvalue for the ratio still needs to be determined. METHODS: 114 sera from patients with histologically confirmed benign prostatic hyperplasia (BPH; n = 58) and cancer of the prostate (CaP; n = 56) were analyzed with two different assays. Free PSA (free), total PSA (total) and the free-to-total- PSA ratio (ratio) were determined employing Enzym-Test PSA und freies PSA (Boehringer Mannheim, Germany) and Immulite PSA und freies PSA (DPC Biermann, Bad Nauheim, Germany) RESULTS: The statistical results are tabulated below: [table: see text] CONCLUSION: Direct comparison of the two assays revealed a high statistical correlation (r = 0.94-0.99) for free and total PSA. In contrast, the ratio of the two assays was not as reproducible (r = 0.81-0.83). This result indicates that the reference range for the ratio is dependent on the assay employed and an that uncritical use of an applied reference range can be counter-productive.


Assuntos
Antígeno Prostático Específico/sangue , Hiperplasia Prostática/diagnóstico , Neoplasias da Próstata/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/sangue , Hiperplasia Prostática/patologia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Ligação Proteica , Kit de Reagentes para Diagnóstico , Valores de Referência , Análise de Regressão , Reprodutibilidade dos Testes
11.
Blood ; 93(9): 2884-97, 1999 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10216083

RESUMO

Heparan sulfate (HS) proteoglycans of bone marrow (BM) stromal cells and their extracellular matrix are important components of the microenvironment of hematopoietic tissues and are involved in the interaction of hematopoietic stem and stromal cells. Although previous studies have emphasized the role of HS proteoglycan synthesis by BM stromal cells, we have recently shown that the human hematopoietic progenitor cell line TF-1 also expressed an HS proteoglycan. Immunochemical, reverse transcriptase-polymerase chain reaction (RT-PCR), and Northern blot analysis of this HS proteoglycan showed that it was not related to the syndecan family of HS proteoglycans or to glypican. To answer the question of whether the expression of HS proteoglycans is associated with the differentiation state of hematopoietic progenitor cells, we have analyzed the proteoglycan synthesis of several murine and human hematopoietic progenitor cell lines. Proteoglycans were isolated from metabolically labeled cells and purified by several chromatographic steps. Isolation and characterization of proteoglycans from the cell lines HEL and ELM-D, which like TF-1 cells have an immature erythroid phenotype, showed that these cells synthesize the same HS proteoglycan, previously detected in TF-1 cells, as a major proteoglycan. In contrast, cell lines of the myeloid lineage, like the myeloblastic/promyelocytic cell lines B1 and B2, do not express HS proteoglycans. Taken together, our data strongly suggest that expression of this HS proteoglycan in hematopoietic progenitor cell lines is associated with the erythroid lineage. To prove this association we have analyzed the proteoglycan expression in the nonleukemic multipotent stem cell line FDCP-Mix-A4 after induction of erythroid or granulocytic differentiation. Our data show that HS proteoglycan expression is induced during early erythroid differentiation of multipotent hematopoietic stem cells. In contrast, during granulocytic differentiation, no expression of HS proteoglycans was observed.


Assuntos
Eritrócitos/citologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/fisiologia , Proteoglicanas de Heparan Sulfato/genética , Diferenciação Celular , Linhagem Celular , Membrana Celular/metabolismo , Cromatografia em Gel , DNA Complementar , Eritrócitos/fisiologia , Proteoglicanas de Heparan Sulfato/biossíntese , Proteoglicanas de Heparan Sulfato/isolamento & purificação , Humanos , Imuno-Histoquímica , Cinética , Glicoproteínas de Membrana/genética , Proteoglicanas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sindecana-2 , Sindecana-4
12.
Biochem J ; 327 ( Pt 2): 473-80, 1997 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-9359418

RESUMO

Proteoglycans of bone-marrow stromal cells and their extracellular matrix are important components of the haematopoietic microenvironment. Recently, several studies have indicated that they are involved in the interaction of haematopoietic stem and stromal cells. However, a detailed characterization of the heparan sulphate proteoglycans synthesized by bone-marrow stromal cells is still lacking. Here we report on the isolation and characterization of proteoglycans from the haematopoietic stromal cell line MS-5, that efficiently supports the growth and differentiation of human and murine haematopoietic progenitor cells. Biochemical characterization of purified proteoglycans revealed that the haematopoietic stromal cell line MS-5 synthesizes, in addition to chondroitin sulphate proteoglycans, several different heparan sulphate proteoglycans. Immunochemical analysis, using specific antibodies against the different members of the syndecan family, glypican, betaglycan and perlecan, showed that MS-5 cells synthesize all these different heparan sulphate proteoglycans. These data were further supported by reverse-transcriptase PCR and confirmed by sequence and Northern blot analysis. The relative abundance of the different heparan sulphate proteoglycans was estimated on the protein and mRNA levels.


Assuntos
Células da Medula Óssea/citologia , Células-Tronco Hematopoéticas/metabolismo , Proteoglicanas de Heparan Sulfato/biossíntese , Células Estromais/metabolismo , Animais , Células da Medula Óssea/metabolismo , Diferenciação Celular , Divisão Celular , Linhagem Celular , Humanos , Camundongos , Reação em Cadeia da Polimerase , Proteoglicanas/biossíntese , Receptores de Fatores de Crescimento Transformadores beta/biossíntese , Sulfatos/metabolismo
13.
Eur J Clin Chem Clin Biochem ; 35(2): 95-9, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9056750

RESUMO

Heparan sulphate proteoglycans are major components of the glomerular basement membrane and play a key role in their molecular organization and function. Moreover, their presence is essential for the maintenance of the selective permeability of the glomerular basement membrane. Recently, we have isolated and characterized a novel, small basement membrane associated heparan sulphate proteoglycan from human aorta and kidney. Using specific monoclonal antibodies we have shown that the novel heparan sulphate proteoglycan is predominantly located in the glomerular basement membrane, to a lesser extent in the basement membrane of tubuli, and also in the mesangium. Turnover or, in the course of kidney diseases, degradation of heparan sulphate proteoglycan from glomerular basement membranes may lead to urinary excretion of heparan sulphate proteoglycan. Therefore, changes in the structure and function of glomerular basement membranes may be directly detected by measuring the excretion of a component of this basement menbrane, e. g. heparan sulphate proteoglycan into urine. Here we describe the establishment of an enzyme immunoassay for the sensitive detection of the novel, small heparan sulphate proteoglycan in urine. In this assay the specific monoclonal antibody 1F10/B8, which recognizes a core protein epitope, was used to detect the polyanionic heparan sulphate proteoglycan bound to the surface of a cationic charge modified microtitre plate. This assay allows the sensitive and specific detection of the small heparan sulphate proteoglycan, which is released from the glomerular basement membrane into urine during normal turnover and also in the course of kidney diseases.


Assuntos
Epitopos/análise , Heparitina Sulfato/análise , Rim/química , Proteoglicanas/análise , Animais , Anticorpos Monoclonais , Especificidade de Anticorpos , Aorta/química , Membrana Basal/química , Feminino , Proteoglicanas de Heparan Sulfato , Heparitina Sulfato/imunologia , Heparitina Sulfato/urina , Humanos , Técnicas Imunoenzimáticas , Rim/ultraestrutura , Camundongos , Camundongos Endogâmicos BALB C , Proteoglicanas/imunologia , Proteoglicanas/urina , Sensibilidade e Especificidade
14.
J Am Soc Nephrol ; 7(12): 2670-6, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8989747

RESUMO

The aim of the study presented here was to investigate whether, in patients showing immediate graft function after renal transplantation, cold-ischemia and reperfusion lead to damage of the glomerular basement membrane and consequently to a loss of heparan sulfate proteoglycans. Loss of these heparan sulfate proteoglycans is a major cause of proteinuria. Time-dependent changes in urinary excretion rates of heparan sulfate proteoglycans but also of total protein, albumin, low- and high-molecular-weight proteins were analyzed quantitatively and by polyacrylamid-gel-electrophoresis in eight patients. Immediately after renal transplantation, severe proteinuria with an excretion rate of up to 251 +/- 108 mg/min was apparent and rapidly declined within 24 h to 4.11 +/- 2.80 mg/min. The gel-electrophoretic pattern showed a nonselective glomerular and tubular proteinuria. The excretion rate of heparan sulfate proteoglycan was increased in this initial reperfusion phase (up to 7 h), most probably because of ischemia- and reperfusion-induced damage of the glomerular basement membrane. The initial nonselective glomerular proteinuria disappeared within 48 h, changing to a mild selective glomerular proteinuria. In this second phase (7 to 48 h), lower levels of heparan sulfate proteoglycan excretion were observed (0.54 +/- 0.54 microgram/min versus 1.66 +/- 1.93 micrograms/min, P < 0.05). However, during the repair process of the glomerular basement membrane, heparan sulfate proteoglycan is synthesized de novo, leading to an increasing heparan sulfate proteoglycan content of the glomerular basement membrane. This second phase is paralleled by the change from a nonselective to a selective glomerular proteinuria. In the third phase, when the heparan sulfate proteoglycan content of the glomerular basement membrane normalizes, glomerular proteinuria was abolished in most of the patients.


Assuntos
Heparitina Sulfato/urina , Transplante de Rim/efeitos adversos , Proteinúria/etiologia , Proteoglicanas/urina , Adulto , Membrana Basal/lesões , Membrana Basal/metabolismo , Membrana Basal/patologia , Feminino , Proteoglicanas de Heparan Sulfato , Heparitina Sulfato/metabolismo , Humanos , Imuno-Histoquímica , Rim/lesões , Rim/metabolismo , Rim/patologia , Glomérulos Renais/lesões , Glomérulos Renais/metabolismo , Glomérulos Renais/patologia , Transplante de Rim/patologia , Transplante de Rim/fisiologia , Masculino , Pessoa de Meia-Idade , Proteoglicanas/metabolismo , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia
15.
Biochem J ; 318 ( Pt 3): 1051-6, 1996 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-8836155

RESUMO

Monoclonal antibodies (mAbs) were prepared against aggrecan which has been isolated from human articular cartilage and purified by several chromatographic steps. One of these mAbs, the aggrecan-specific mAb 3D12/H7, was selected for further characterization. The data presented indicate that this mAb recognizes a novel domain of keratan sulphate chains from aggrecan: (1) immunochemical staining of aggrecan is abolished by treatment with keratanase/keratanase II, but not with keratanase or chondroitin sulphate lyase AC/ABC; (2) after chemical deglycosylation of aggrecan no staining of the core-protein was observed; (3) different immunochemical reactivity was observed against keratan sulphates from articular cartilage, intervertebral disc and cornea for the mAbs 3D12/H7 and 5D4. For further characterization of the epitope, reduced and 3H-labelled keratan sulphate chains were prepared. In an IEF-gel-shift assay it was shown that the 3H-labelled oligosaccharides obtained after keratanase digestion of reduced and 3H-labelled keratan sulphate chains were recognized by the mAb 3D12/H7. Thus it can be concluded that the mAb 3D12/H7 recognizes an epitope in the linkage region present in, at least some, keratan sulphate chains of the large aggregating proteoglycan from human articular cartilage. Moreover, this domain seems to be expressed preferentially on those keratan sulphate chains which occur in the chondroitin sulphate-rich region of aggrecan, since the antibody does not recognize the keratan sulphate-rich region obtained after combined chondroitinase AC/ABC and trypsin digestion of aggrecan.


Assuntos
Cartilagem Articular/química , Proteínas da Matriz Extracelular , Glicosídeo Hidrolases , Sulfato de Queratano/química , Proteoglicanas/química , Agrecanas , Anticorpos Monoclonais , Sequência de Carboidratos , Humanos , Imunoquímica , Sulfato de Queratano/imunologia , Sulfato de Queratano/isolamento & purificação , Lectinas Tipo C , Dados de Sequência Molecular , Estrutura Molecular , Proteoglicanas/imunologia , Proteoglicanas/isolamento & purificação , beta-Galactosidase
16.
Biochem J ; 317 ( Pt 1): 203-12, 1996 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-8694765

RESUMO

Proteoglycans of bone-marrow stromal cells and their extracellular matrix are important components of the microenvironment of haematopoietic tissues. Proteoglycans might also be involved in the interaction of haematopoietic stem and stromal cells. Recently, several studies have been reported on the proteoglycan synthesis of stromal cells, but little is known about the proteoglycan synthesis of haematopoietic stem or progenitor cells. Here we report on the isolation and characterization of proteoglycans from two haematopoietic progenitor cell lines, the murine FDCP-Mix A4 and the human TF-1 cell line. Proteoglycans were isolated from metabolically labelled cells and purified by several chromatographic steps, including anion-exchange and size-exclusion chromatography. Biochemical characterization was performed by electrophoresis or gel-filtration chromatography before and after digestion with glycosaminoglycan-specific enzymes or HNO2 treatment. Whereas FDCP-Mix A4 cells synthesize a homogeneous chondroitin 4-sulphate proteoglycan, isolation and characterization of proteoglycans from the human cell line TF-1 revealed, that TF-1 cells synthesize, in addition to a chondroitin sulphate proteoglycan, a heparan sulphate proteoglycan as major proteoglycan. For this heparan sulphate proteoglycan a core protein size of approx. 59 kDa was determined. Immunochemical analysis of this heparan sulphate proteoglycan revealed that it is not related to the syndecan family nor to glypican.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Heparitina Sulfato/biossíntese , Proteoglicanas/biossíntese , Animais , Anticorpos Monoclonais , Linhagem Celular , Colo do Útero/citologia , Proteoglicanas de Sulfatos de Condroitina/biossíntese , Proteoglicanas de Sulfatos de Condroitina/imunologia , Feminino , Fibroblastos/citologia , Proteoglicanas de Heparan Sulfato , Heparitina Sulfato/imunologia , Humanos , Camundongos , Proteoglicanas/imunologia , Especificidade da Espécie
19.
Lab Invest ; 73(2): 172-82, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7543628

RESUMO

BACKGROUND: Interactions of tumor cells and extracellular matrix (ECM) components are crucial determinants of tumor cell spreading and metastatic activity. Particularly tenascin (TN) as a member of the adhesion modulating family of ECM and its alternatively spliced isoforms became the matter of interest in ECM changes associated with malignancy. EXPERIMENTAL DESIGN: We analyzed the composition of the stromal- and basement membrane-associated ECM of colorectal adenomas and carcinomas using indirect immunofluorescence. Tenascin was investigated by immunoblot of snap frozen tumor specimens. RESULTS: Fibronectin (FN), TN, and chondroitin sulfate proteoglycan were the major components of the tumor stroma. Normal basement membrane components like laminin (LM), collagen type IV, and heparan sulfate proteoglycan were down-regulated. In the center of the tumor, tumor glands were surrounded by discontinuous basement membranes. At the tumor-host interface and in solid, poorly differentiated tumors, no immunoreactivity with normal basement membrane components was found. However, in cases with pericellular anti-LM staining, LM immunoreactivity was also found at the tumor-host interface. An alternatively spliced isoform of TN with a molecular weight of 330 kDa was found in seven of 15 carcinomas. In four of these cases, an alternatively spliced isoform of FN containing the ED-B segment was present. CONCLUSIONS: The coexpression of alternative splicing of FN and TN suggests that there may be common regulation mechanisms. The matrix composition found in the present study resembles that of healing wounds and probably favors the invasive spread of tumor cells.


Assuntos
Carcinoma/química , Moléculas de Adesão Celular Neuronais/genética , Neoplasias Colorretais/química , Proteínas da Matriz Extracelular/análise , Proteínas da Matriz Extracelular/genética , Fibronectinas/genética , Adenoma/química , Processamento Alternativo/genética , Membrana Basal/química , Colágeno/análise , Humanos , Imuno-Histoquímica , Mucosa Intestinal/química , Laminina/análise , Tenascina
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