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1.
J Cancer Res Clin Oncol ; 149(10): 7743-7750, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37010585

RESUMO

PURPOSE: The evolutionary-conserved Wnt/ß-CATENIN (WBC) pathway has been implicated in the pathogenesis of different solid malignant tumors. We evaluated the prognostic relevance of ß-CATENIN, a pivotal mediator of WBC activation, in patients with human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC). METHODS: We analyzed if patients with HPV-positive HNSCC from the "The Cancer Genome Atlas" (TCGA cohort, n = 41) can be stratified based on their CTNNB1 mRNA expression. Moreover, in a tissue microarray (TMA) of primary tumor sections from HPV-positive HNSCC patients treated in a tertiary academic center (in-house cohort, n = 31), we evaluated the prognostic relevance of ß-CATENIN expression on protein level. RESULTS: In silico mining of CTNNB1 expression in HPV-positive HNSCC revealed that high CTNNB1 expression was linked to better overall survival (OS, p = 0.062). Moreover, high ß-CATENIN expression was significantly associated with a better OS in our in-house cohort (p = 0.035). CONCLUSION: Based on these findings, we postulate that ß-CATENIN expression could serve (potentially in conjunction with other WBC pathway members) as a marker for better survival outcomes in patients with HPV-positive HNSCC. However, it is evident that future studies on bigger cohorts are warranted.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Infecções por Papillomavirus , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/complicações , Prognóstico , beta Catenina/metabolismo , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/patologia , Carcinoma de Células Escamosas/patologia
2.
Invest New Drugs ; 41(2): 193-201, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36809443

RESUMO

BACKGROUND: New chemotherapy agents are warranted for head and neck squamous cell carcinoma (HNSCC), particularly for incidence-rising HPV-positive tumors. Based on the evidence of Notch pathway involvement in cancer promotion and progression, we aimed to gain insights into the in vitro antineoplastic effects of gamma-secretase inhibition in HPV-positive and -negative HNSCC models. METHODS: All in vitro experiments were conducted in two HPV-negative (Cal27 and FaDu) and one HPV-associated HNSCC cell line (SCC154). The influence of the gamma-secretase inhibitor PF03084014 (PF) on proliferation, migration, colony forming, and apoptosis was assessed. RESULTS: We observed significant anti-proliferative, anti-migratory, anti-clonogenic, and pro-apoptotic effects in all three HNSCC cell lines. Furthermore, synergistic effects with concomitant radiation were observable in the proliferation assay. Interestingly, effects were slightly more potent in the HPV-positive cells. CONCLUSION: We provided novel insights into the potential therapeutic relevance of gamma-secretase inhibition in HNSCC cell lines in vitro. Therefore, PF may become a viable treatment option for patients with HNSCC, particularly for patients with HPV-induced malignancy. Indeed, further in vitro and in vivo experiments should be conducted to validate our results and decipher the mechanism behind the observed anti-neoplastic effects.


Assuntos
Antineoplásicos , Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Infecções por Papillomavirus , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Infecções por Papillomavirus/tratamento farmacológico , Infecções por Papillomavirus/complicações , Antineoplásicos/farmacologia , Linhagem Celular Tumoral
3.
Eur Arch Otorhinolaryngol ; 280(1): 399-408, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36001136

RESUMO

Beta-catenin is known to be a vital component of the canonical Wnt signaling cascade, involved in the carcinogenesis of different solid tumors. We aimed to evaluate the effects of Beta-catenin inhibition in head and neck squamous cell carcinoma (HNSCC) in vitro. The small molecular compound MSAB was used to inhibit Wnt/Beta-catenin signaling in a human papillomavirus (HPV)-positive and HPV-negative cell line and its effects on cell proliferation, migration, colony formation, apoptosis, as well as radiosensitizing properties were assessed. Significant antineoplastic effects were observed in both cell lines. Interestingly, stronger anti-neoplastic and radiosensitizing effects were observed in the HPV-negative cell line, whereas stronger anti-migratory potential was detected in HPV-positive HNSCC cells. In conclusion, our findings suggest MSAB as a potential therapeutic agent for HNSCC. Further studies are warranted to unravel the mechanistic background of our findings.


Assuntos
Neoplasias de Cabeça e Pescoço , Infecções por Papillomavirus , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , beta Catenina/metabolismo , Linhagem Celular Tumoral
4.
Pharmaceuticals (Basel) ; 15(3)2022 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-35337176

RESUMO

Wnt/Beta-Catenin signaling is involved in the carcinogenesis of different solid malignant tumors. The interaction of Creb-binding protein (CBP) with Beta-Catenin is a pivotal component of the Wnt/Beta-Catenin signaling pathway. The first aim of this study was to evaluate the association of CBP expression with survival in patients with human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC). Second, the in vitro effects of the inhibition of CBP/Beta-Catenin interaction were analyzed. In particular, the effects of ICG-001, an inhibitor of CBP/Beta-Catenin interaction, on proliferation, cell death, modulation of Wnt/Beta-Catenin target expression, and cell migration were examined in vitro. High CBP expression is significantly associated with better survival on mRNA and protein levels. Furthermore, we observed cytotoxic as well as anti-migratory effects of ICG-001. These effects were particularly more potent in the HPV-positive than in the -negative cell line. Mechanistically, ICG-001 treatment induced apoptosis and led to a downregulation of CBP, c-MYC, and Cyclin D1 in HPV-positive cells, indicating inhibition of Wnt/Beta-Catenin signaling. In conclusion, high CBP expression is observed in HPV-positive HNSCC patients with a good prognosis, and ICG-001 showed a promising antineoplastic potential, particularly in HPV-positive HNSCC cells. Therefore, ICG-001 may potentially become an essential component of treatment de-escalation regimens for HPV-positive HNSCC. Further studies are warranted for additional assessment of the mechanistic background of our in vitro findings.

5.
J Pers Med ; 11(11)2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34834580

RESUMO

Many patients with adenoid-cystic carcinoma (ACC) experience an indolent course of disease over many years but face late recurrence, and long-term survivors are rare. Due to its infrequent occurrence, it is hard to predict outcome in these patients. The fibrinogen-to-lymphocyte ratio (FLR) was recently proposed as an outcome prognosticator in different cancer entities. We aimed to investigate its prognostic relevance in patients with head and neck ACC. This retrospective analysis was performed including all patients treated for ACC between 1998 and 2020. The FLR ratio was calculated based on pretreatment values (0-7 days). The study cohort was dichotomized based on optimized threshold value and compared for differences in outcome (overall survival (OS) and disease-free survival (DFS)). In the cohort of 39 included patients, the OS was significantly longer in the low (n = 28) compared to the high pretreatment FLR group (n = 11) (median OS 150.5 months, 95% confidence intervals (CI) 85.3-215.7 months vs. 29.4 months, 95% CI not reached; p = 0.0093). Similarly, the DFS was significantly longer in the low FLR group (median DFS 74.5 months, 95% CI 30.6-118.4 months vs. 11.0 months, 95% CI 5.1-16.9 months; p = 0.019). The FLR is an easily obtainable and simple marker and may be a valuable outcome prognosticator in patients with ACC. Further studies are needed for validation of our results.

6.
J Nucl Med ; 56(2): 190-5, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25613533

RESUMO

UNLABELLED: The aim of this study was to compare the overall survival of a large, single-center cohort of patients who had differentiated thyroid cancer (DTC) with that of a matched general population. METHODS: We analyzed 2,428 consecutive patients who had DTC and underwent treatment from 1965 to 2013 at the Department of Nuclear Medicine, University Hospital of Münster, Münster, Germany, according to international standards. Patients were classified on the basis of the current, seventh edition of the American Joint Committee on Cancer/Union for International Cancer Control classification system. Additionally, a subgroup analysis with regard to age at diagnosis was performed. The overall survival of the patients was compared with the expected survival of the general population on the basis of age and sex, as provided by the Federal Statistical Office of Germany. RESULTS: Compared with the expected survival, the overall survival of patients with stage I disease paradoxically was significantly better (P < 0.001). In the subgroup analysis, a significantly lower mortality rate was observed in elderly patients (≥60 y old) with stage I disease. On the other hand, patients between 20 and 45 y of age and with distant metastases at diagnosis had a significantly increased standardized mortality rate. In contrast, other patients with stage II disease and more than 45 y old had a normal mortality rate. The mortality rate was significantly increased in all patients with stage IVC disease. CONCLUSION: Older patients with more limited disease paradoxically had better survival than would be expected on the basis of age and sex, whereas young adults as well as patients more than 45 y old and with distant metastases had increased mortality rates. For all other DTC patients, regardless of age or TNM stage, no significant survival difference was seen.


Assuntos
Expectativa de Vida , Neoplasias da Glândula Tireoide/mortalidade , Adulto , Fatores Etários , Idoso , Diferenciação Celular , Estudos de Coortes , Feminino , Seguimentos , Alemanha , Humanos , Radioisótopos do Iodo/uso terapêutico , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico , Neoplasias da Glândula Tireoide/radioterapia , Resultado do Tratamento , Adulto Jovem
7.
Clin Endocrinol (Oxf) ; 80(6): 911-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24417487

RESUMO

OBJECTIVE: The seventh edition of the American Joint Committee on Cancer (AJCC) has more detailed staging categories for differentiated thyroid cancer (DTC) than the fifth edition. The aim was to compare potential alterations in the disease-specific (DSS), event-free (EFS) and overall survival (OS), after reclassification from the fifth to the seventh edition. METHODS: Data of 2460 patients with DTC referred to our centre were reclassified from the fifth to the seventh edition of AJCC. DSS, EFS and OS were calculated using the Kaplan-Meier method and compared by the log-rank test. The relative abilities of each edition to predict survival were calculated by the proportion of variance explained (PVE). RESULTS: After reclassification to the seventh edition, there was an increase in stage I and IV patients from 58·1% to 65·0% and from 6·2% to 10·1%, respectively, and a corresponding decrease in stage II and III patients from 22·4% to 12·5% and 13·3% to 12·4%, respectively. As to DSS, the seventh edition had only a marginally higher PVE value than the fifth edition. With respect to EFS, the predictability of the seventh edition was even inferior to that of the fifth edition. Similarly, with regard to OS, the PVE value was slightly better for the older edition. Furthermore, a comparison only for those patients affected by the reclassification revealed no differences for DSS, EFS or OS between classifications. CONCLUSION: When comparing the stages of the seventh with the fifth edition of the AJCC for DTC, there was no significant difference in predicting DSS, EFS and OS.


Assuntos
Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/radioterapia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Radioisótopos do Iodo/uso terapêutico , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Prognóstico , Reprodutibilidade dos Testes , Resultado do Tratamento
8.
Hum Resour Health ; 11: 24, 2013 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-23734939

RESUMO

BACKGROUND: In light of Germany's ageing society, demand for nursing professionals is expected to increase in the coming years. This will pose a challenge for policy makers to increase the supply of nursing professionals. METHODOLOGY: To portray the different possible developments in the supply of nursing professionals, we projected the supply of formally trained nurses and the potential supply of persons who are able to work in a nursing profession. This potential supply of nursing professionals was calculated on the basis of empirical information on occupational mobility provided by the German Microcensus 2005 (Labour Force Survey). We also calculated how the supply of full-time equivalents (FTEs) will develop if current employment structures develop in the direction of employment behaviour in nursing professions in eastern and western Germany. We then compared these different supply scenarios with two demand projections ('status quo' and 'compression of morbidity' scenarios) from Germany's Federal Statistical Office. RESULTS: Our results show that, even as early as 2005, meeting demand for FTEs in nursing professions was not arithmetically possible when only persons with formal qualification in a nursing profession were taken into account on the supply side. When additional semi-skilled nursing professionals are included in the calculation, a shortage of labour in nursing professions can be expected in 2018 when the employment structure for all nursing professionals remains the same as the employment structure seen in Germany in 2005 (demand: 'status quo scenario'). Furthermore, given an employment structure as in eastern Germany, where more nursing professionals work on a full-time basis with longer working hours, a theoretical shortage of nursing professionals could be delayed until 2024. CONCLUSIONS: Our analysis of occupational flexibility in the nursing field indicates that additional potential supply could be generated by especially training more young people for a nursing profession as they tend to stay in their initial occupation. Furthermore, the number of FTEs in nursing professions could be increased by promoting more full-time contracts in Western Germany. Additionally, employment contracts for just a small number of weekly working hours (marginal employment) cannot be considered an adequate instrument for keeping formally trained nursing professionals employed in the nursing field.

9.
Mol Syst Biol ; 9: 653, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23549481

RESUMO

Mycoplasma pneumoniae, a threatening pathogen with a minimal genome, is a model organism for bacterial systems biology for which substantial experimental information is available. With the goal of understanding the complex interactions underlying its metabolism, we analyzed and characterized the metabolic network of M. pneumoniae in great detail, integrating data from different omics analyses under a range of conditions into a constraint-based model backbone. Iterating model predictions, hypothesis generation, experimental testing, and model refinement, we accurately curated the network and quantitatively explored the energy metabolism. In contrast to other bacteria, M. pneumoniae uses most of its energy for maintenance tasks instead of growth. We show that in highly linear networks the prediction of flux distributions for different growth times allows analysis of time-dependent changes, albeit using a static model. By performing an in silico knock-out study as well as analyzing flux distributions in single and double mutant phenotypes, we demonstrated that the model accurately represents the metabolism of M. pneumoniae. The experimentally validated model provides a solid basis for understanding its metabolic regulatory mechanisms.


Assuntos
Metabolismo Energético/genética , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Mycoplasma pneumoniae/genética , Mycoplasma pneumoniae/metabolismo , Simulação por Computador , Redes e Vias Metabólicas/genética , Modelos Biológicos , Mutação
10.
Mol Biosyst ; 9(7): 1743-55, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23598864

RESUMO

Systems metabolomics, the identification and quantification of cellular metabolites and their integration with genomics and proteomics data, promises valuable functional insights into cellular biology. However, technical constraints, sample complexity issues and the lack of suitable complementary quantitative data sets prevented accomplishing such studies in the past. Here, we present an integrative metabolomics study of the genome-reduced bacterium Mycoplasma pneumoniae. We experimentally analysed its metabolome using a cross-platform approach. We explain intracellular metabolite homeostasis by quantitatively integrating our results with the cellular inventory of proteins, DNA and other macromolecules, as well as with available building blocks from the growth medium. We calculated in vivo catalytic parameters of glycolytic enzymes, making use of measured reaction velocities, as well as enzyme and metabolite pool sizes. A quantitative, inter-species comparison of absolute and relative metabolite abundances indicated that metabolic pathways are regulated as functional units, thereby simplifying adaptive responses. Our analysis demonstrates the potential for new scientific insight by integrating different types of large-scale experimental data from a single biological source.


Assuntos
Genômica , Metabolômica , Mycoplasma pneumoniae/genética , Mycoplasma pneumoniae/metabolismo , Proteômica , Aminoácidos/metabolismo , Genômica/métodos , Glicólise , Metaboloma , Metabolômica/métodos , Proteoma , Proteômica/métodos
11.
Mol Biosyst ; 9(6): 1249-56, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23579234

RESUMO

Quantitative proteomics is an essential tool in proteome research since it enables measuring changes in protein abundance in response to biological perturbations. During the last few years, different quantitative strategies have been developed in proteomics to compare different experimental conditions, including label-free and isobaric chemical labeling approaches. Here we show that different quantitation techniques have an important influence on detected sample variability, and we use the combination of six different quantitation strategies to perform a proteome comparison of three different Mycoplasma pneumoniae strains (ldh knockdown, Δprkc, and wild-type). The integration of the different datasets indicates that the ldh knockdown strongly affects the abundance of ribosomal proteins and enzymes involved in the regulation of the cellular redox state, whereas the prkc deletion affects key cellular physiological processes such as protein and DNA synthesis, and cytoadherence.


Assuntos
Proteínas de Bactérias/genética , L-Lactato Desidrogenase/genética , Mycoplasma pneumoniae/química , Mycoplasma pneumoniae/genética , Proteína Quinase C-alfa/genética , Proteoma/análise , Deleção de Genes , Genoma Bacteriano , Mapeamento de Interação de Proteínas , Proteômica
12.
Mol Syst Biol ; 8: 571, 2012 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-22373819

RESUMO

Protein post-translational modifications (PTMs) represent important regulatory states that when combined have been hypothesized to act as molecular codes and to generate a functional diversity beyond genome and transcriptome. We systematically investigate the interplay of protein phosphorylation with other post-transcriptional regulatory mechanisms in the genome-reduced bacterium Mycoplasma pneumoniae. Systematic perturbations by deletion of its only two protein kinases and its unique protein phosphatase identified not only the protein-specific effect on the phosphorylation network, but also a modulation of proteome abundance and lysine acetylation patterns, mostly in the absence of transcriptional changes. Reciprocally, deletion of the two putative N-acetyltransferases affects protein phosphorylation, confirming cross-talk between the two PTMs. The measured M. pneumoniae phosphoproteome and lysine acetylome revealed that both PTMs are very common, that (as in Eukaryotes) they often co-occur within the same protein and that they are frequently observed at interaction interfaces and in multifunctional proteins. The results imply previously unreported hidden layers of post-transcriptional regulation intertwining phosphorylation with lysine acetylation and other mechanisms that define the functional state of a cell.


Assuntos
Acetilesterase/metabolismo , Tamanho do Genoma/genética , Lisina/metabolismo , Redes e Vias Metabólicas/genética , Pneumonia por Mycoplasma/genética , Proteínas Quinases/metabolismo , Acetilação , Domínio Catalítico/genética , Evolução Molecular , Redes Reguladoras de Genes/genética , Redes Reguladoras de Genes/fisiologia , Genoma Bacteriano/genética , Redes e Vias Metabólicas/fisiologia , Modelos Biológicos , Organismos Geneticamente Modificados , Fosforilação/fisiologia , Pneumonia por Mycoplasma/metabolismo , Processamento de Proteína Pós-Traducional/genética , Proteoma/genética , Proteoma/metabolismo
13.
Mol Syst Biol ; 7: 511, 2011 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-21772259

RESUMO

Biological function and cellular responses to environmental perturbations are regulated by a complex interplay of DNA, RNA, proteins and metabolites inside cells. To understand these central processes in living systems at the molecular level, we integrated experimentally determined abundance data for mRNA, proteins, as well as individual protein half-lives from the genome-reduced bacterium Mycoplasma pneumoniae. We provide a fine-grained, quantitative analysis of basic intracellular processes under various external conditions. Proteome composition changes in response to cellular perturbations reveal specific stress response strategies. The regulation of gene expression is largely decoupled from protein dynamics and translation efficiency has a higher regulatory impact on protein abundance than protein turnover. Stochastic simulations using in vivo data show how low translation efficiency and long protein half-lives effectively reduce biological noise in gene expression. Protein abundances are regulated in functional units, such as complexes or pathways, and reflect cellular lifestyles. Our study provides a detailed integrative analysis of average cellular protein abundances and the dynamic interplay of mRNA and proteins, the central biomolecules of a cell.


Assuntos
Proteínas de Bactérias/metabolismo , Mycoplasma pneumoniae/genética , Proteoma/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Bactérias/genética , Meios de Cultura , Bases de Dados Genéticas , Eletroforese em Gel de Poliacrilamida , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Espectrometria de Massas , Mycoplasma pneumoniae/metabolismo , Processamento de Proteína Pós-Traducional , Proteoma/genética , Processamento Pós-Transcricional do RNA , RNA Mensageiro/genética , Análise de Sequência de RNA
14.
Bioinformatics ; 26(14): 1685-9, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20519287

RESUMO

MOTIVATION: Molecular chaperones prevent the aggregation of their substrate proteins and thereby ensure that they reach their functional native state. The bacterial GroEL/ES chaperonin system is understood in great detail on a structural, mechanistic and functional level; its interactors in Escherichia coli have been identified and characterized. However, a long-standing question in the field is: What makes a protein a chaperone substrate? RESULTS: Here we identify, using a bioinformatics-based approach a simple set of quantities, which characterize the GroEL-substrate proteome. We define three novel parameters differentiating GroEL interactors from other cellular proteins: lower rate of evolution, hydrophobicity and aggregation propensity. Combining them with other known features to a simple Bayesian predictor allows us to identify known homologous and heterologous GroEL substrateproteins. We discuss our findings in relation to established mechanisms of protein folding and evolutionary buffering by chaperones.


Assuntos
Chaperoninas/química , Biologia Computacional/métodos , Chaperonina 60/química , Chaperonina 60/metabolismo , Evolução Molecular , Cinética , Dobramento de Proteína , Proteoma/metabolismo
15.
Science ; 326(5957): 1235-40, 2009 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-19965468

RESUMO

The genome of Mycoplasma pneumoniae is among the smallest found in self-replicating organisms. To study the basic principles of bacterial proteome organization, we used tandem affinity purification-mass spectrometry (TAP-MS) in a proteome-wide screen. The analysis revealed 62 homomultimeric and 116 heteromultimeric soluble protein complexes, of which the majority are novel. About a third of the heteromultimeric complexes show higher levels of proteome organization, including assembly into larger, multiprotein complex entities, suggesting sequential steps in biological processes, and extensive sharing of components, implying protein multifunctionality. Incorporation of structural models for 484 proteins, single-particle electron microscopy, and cellular electron tomograms provided supporting structural details for this proteome organization. The data set provides a blueprint of the minimal cellular machinery required for life.


Assuntos
Proteínas de Bactérias/análise , Genoma Bacteriano , Complexos Multiproteicos/análise , Mycoplasma pneumoniae/química , Mycoplasma pneumoniae/genética , Proteoma , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Biologia Computacional , Espectrometria de Massas/métodos , Redes e Vias Metabólicas , Microscopia Eletrônica , Modelos Biológicos , Modelos Moleculares , Complexos Multiproteicos/metabolismo , Mycoplasma pneumoniae/metabolismo , Mycoplasma pneumoniae/ultraestrutura , Reconhecimento Automatizado de Padrão , Mapeamento de Interação de Proteínas , Biologia de Sistemas
16.
Science ; 326(5957): 1263-8, 2009 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-19965476

RESUMO

To understand basic principles of bacterial metabolism organization and regulation, but also the impact of genome size, we systematically studied one of the smallest bacteria, Mycoplasma pneumoniae. A manually curated metabolic network of 189 reactions catalyzed by 129 enzymes allowed the design of a defined, minimal medium with 19 essential nutrients. More than 1300 growth curves were recorded in the presence of various nutrient concentrations. Measurements of biomass indicators, metabolites, and 13C-glucose experiments provided information on directionality, fluxes, and energetics; integration with transcription profiling enabled the global analysis of metabolic regulation. Compared with more complex bacteria, the M. pneumoniae metabolic network has a more linear topology and contains a higher fraction of multifunctional enzymes; general features such as metabolite concentrations, cellular energetics, adaptability, and global gene expression responses are similar, however.


Assuntos
Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Redes e Vias Metabólicas , Mycoplasma pneumoniae/genética , Mycoplasma pneumoniae/metabolismo , Trifosfato de Adenosina/metabolismo , Meios de Cultura , Metabolismo Energético , Enzimas/genética , Enzimas/metabolismo , Perfilação da Expressão Gênica , Glicólise , Mycoplasma pneumoniae/crescimento & desenvolvimento , RNA Bacteriano/genética , RNA Bacteriano/metabolismo , Transdução de Sinais , Biologia de Sistemas , Transcrição Gênica , Óperon de RNAr
17.
FEBS Lett ; 583(24): 3966-73, 2009 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-19850042

RESUMO

The correlation between mRNA and protein abundances in the cell has been reported to be notoriously poor. Recent technological advances in the quantitative analysis of mRNA and protein species in complex samples allow the detailed analysis of this pathway at the center of biological systems. We give an overview of available methods for the identification and quantification of free and ribosome-bound mRNA, protein abundances and individual protein turnover rates. We review available literature on the correlation of mRNA and protein abundances and discuss biological and technical parameters influencing the correlation of these central biological molecules.


Assuntos
Análise em Microsséries/métodos , Biossíntese de Proteínas , Proteínas/análise , RNA Mensageiro/análise , Ribossomos/metabolismo , Biologia de Sistemas/métodos , Códon/metabolismo , Conformação de Ácido Nucleico , Proteínas/metabolismo , RNA Mensageiro/metabolismo , Ribossomos/química
18.
J Oral Maxillofac Surg ; 64(6): 902-9, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16713804

RESUMO

PURPOSE: This study reports on the intraoperative use of noncontact, nonionizing, optical 3-dimensional (3D) exophthalmometry during the repositioning of dislocated globes as a result of trauma. PATIENTS AND METHODS: Ten patients (4 female, 6 male, 41.4+/-15.2 years) with a relative enophthalmos of the globe as a result of zygomatic fractures were included in the study. Preoperatively, en- and exophthalmometry data were assessed from axial CT slices and optical 3D imaging. 3D data were analyzed twice for the assessment of measurement errors. Intraoperatively, optical en- and exophthalmometry was carried out to control the globe position. Surgery was considered successful when the relative en- or exophthalmos no longer exceeded 2 mm. Optical 3D en- and exophthalmometry data were reassessed 5 days and 3 months after surgery. RESULTS: Method error was 0.184 mm for optical 3D en- and exophthalmometry. The preoperatively assessed en- and exophthalmometry data determined from axial CT scans and from optical 3D images did not differ significantly statistically (P=.538). When the preoperative en- and exophthalmometry data were compared to the values assessed at the end of surgery, a significant improvement in globe position was found (P=.005). Although a relative en- or exophthalmos of 2 mm was not exceeded in any of the patients 3 months after surgery, en- and exophthalmometry data differed significantly statistically from the data assessed at the end of the operation (P=.005). CONCLUSIONS: Intraoperative optical en- and exophthalmometry is an effective means to support the surgeon in objectively optimizing the globe position with small measurement errors.


Assuntos
Técnicas de Diagnóstico Oftalmológico , Exoftalmia/diagnóstico , Adulto , Enoftalmia/diagnóstico , Enoftalmia/etiologia , Exoftalmia/etiologia , Feminino , Humanos , Imageamento Tridimensional/métodos , Cuidados Intraoperatórios , Masculino , Fraturas Orbitárias/complicações , Reprodutibilidade dos Testes , Fraturas Zigomáticas/complicações
19.
Cell ; 122(2): 209-20, 2005 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-16051146

RESUMO

The E. coli chaperonin GroEL and its cofactor GroES promote protein folding by sequestering nonnative polypeptides in a cage-like structure. Here we define the contribution of this system to protein folding across the entire E. coli proteome. Approximately 250 different proteins interact with GroEL, but most of these can utilize either GroEL or the upstream chaperones trigger factor (TF) and DnaK for folding. Obligate GroEL-dependence is limited to only approximately 85 substrates, including 13 essential proteins, and occupying more than 75% of GroEL capacity. These proteins appear to populate kinetically trapped intermediates during folding; they are stabilized by TF/DnaK against aggregation but reach native state only upon transfer to GroEL/GroES. Interestingly, substantially enriched among the GroEL substrates are proteins with (betaalpha)8 TIM-barrel domains. We suggest that the chaperonin system may have facilitated the evolution of this fold into a versatile platform for the implementation of numerous enzymatic functions.


Assuntos
Chaperonina 10/metabolismo , Chaperonina 60/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Dobramento de Proteína , Proteoma/metabolismo , Chaperonina 10/genética , Chaperonina 60/genética , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Mutação , Peptidilprolil Isomerase/genética , Peptidilprolil Isomerase/metabolismo , Estrutura Terciária de Proteína , Proteoma/química , Triose-Fosfato Isomerase/química
20.
J Craniomaxillofac Surg ; 33(4): 255-9, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15975809

RESUMO

BACKGROUND: Several severe complications have been described with blow-in fractures. Therefore, immediate surgical treatment of these fractures has been recommended. To date, there is only minimal knowledge on long-term complications of blow-in fractures that have remained untreated. The present case report describes a late complication of an untreated blow-in fracture of the orbital floor. CASE: A 37-year-old male was involved in a car accident 16 years before. At that time, a non-dislocated midfacial fracture was diagnosed and remained untreated because of the lack of clinical symptoms. Four months before surgery an exophthalmos of the left globe began to develop. CT examination revealed a consolidated blow-in fracture of the left orbital floor and an opaque mass around the dislocated bony fragments. By an infraorbital approach the bony fragments and the surrounding mass were removed. Histological examination of the removed material revealed a cystic structure lined with respiratory epithelium. Therefore, the diagnosis 'post-traumatic mucocele in the orbit caused by dislocated respiratory epithelium from the maxillary sinus' was made. CONCLUSION: Even if blow-in fractures do not cause complications immediately after trauma, late complications like mucoceles can occur after several symptom-free years. Therefore, early reconstruction should be intended even in asymptomatic cases of blow-in fractures with minimal displacement of the bony fragments.


Assuntos
Mucocele/etiologia , Fraturas Orbitárias/complicações , Acidentes de Trânsito , Adulto , Exoftalmia/etiologia , Exoftalmia/cirurgia , Humanos , Masculino , Mucocele/cirurgia , Fraturas Orbitárias/cirurgia
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