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1.
FEMS Microbiol Rev ; 47(5)2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37437902

RESUMO

Microbiologically influenced corrosion (MIC) is a phenomenon of increasing concern that affects various materials and sectors of society. MIC describes the effects, often negative, that a material can experience due to the presence of microorganisms. Unfortunately, although several research groups and industrial actors worldwide have already addressed MIC, discussions are fragmented, while information sharing and willingness to reach out to other disciplines are limited. A truly interdisciplinary approach, which would be logical for this material/biology/chemistry-related challenge, is rarely taken. In this review, we highlight critical non-biological aspects of MIC that can sometimes be overlooked by microbiologists working on MIC but are highly relevant for an overall understanding of this phenomenon. Here, we identify gaps, methods, and approaches to help solve MIC-related challenges, with an emphasis on the MIC of metals. We also discuss the application of existing tools and approaches for managing MIC and propose ideas to promote an improved understanding of MIC. Furthermore, we highlight areas where the insights and expertise of microbiologists are needed to help progress this field.


Assuntos
Biofilmes , Metais , Corrosão
2.
Osteoporos Int ; 33(4): 937-941, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34825920

RESUMO

Multiple myeloma (MM) remains incurable. Although early diagnosis improves outcomes, it has been unclear which populations to target for screening with serum electrophoresis, serum free light chains and urine electrophoresis. Here, we assessed the value of MM screening in a Fracture Liaison Service, finding that 1 per 195 fragility fractures has undiagnosed MM, which can be expedited to Haematology Services. PURPOSE: A key role of the Fracture Liaison Service (FLS) is screening for secondary causes of osteoporosis. In 2019, the Royal Osteoporosis Society recommended that all patients attending FLS who are recommended anti-osteoporosis therapy have universal screening for myeloma based on serum electrophoresis, serum free light chains and urine electrophoresis. Here, we examined the impact of universal myeloma screening within an FLS. METHODS: We sampled all patients seen by the Oxfordshire FLS between January and April 2018. The completion rates and outcomes of screening were checked using the hospital and FLS databases. RESULTS: Of 950 patients identified by the FLS, 628 were eligible for MM screening; 473 (75%) of these were female, and the average age was 78.4 years. Overall, 584 had some form of myeloma screening, of which 577 (92%) had serum electrophoresis, 525 (84%) had serum free light chains and 407 (65%) had urine electrophoresis measured. A total of 327 (59%) patients had complete screening. Three patients (0.5%) had newly diagnosed myeloma and were urgently referred to Haematology Services. Furthermore, 46 (8%) patients had a detectable serum paraprotein with a likely diagnosis of monoclonal gammopathy of uncertain significance (MGUS) and referred for community annual surveillance according to local guidelines. CONCLUSION: Addition of universal myeloma screening to laboratory testing identified myeloma in 1 per 195 patients, and its precursor state MGUS in 1 per 13 patients, which may have otherwise been missed. Further analysis with long-term follow-up is needed to clearly define the value of diagnosing MGUS within the FLS setting and establish the benefits vs. costs and methods to improve screening completion rates.


Assuntos
Gamopatia Monoclonal de Significância Indeterminada , Mieloma Múltiplo , Osteoporose , Fraturas por Osteoporose , Idoso , Atenção à Saúde , Feminino , Humanos , Mieloma Múltiplo/complicações , Mieloma Múltiplo/diagnóstico , Osteoporose/epidemiologia , Fraturas por Osteoporose/diagnóstico , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Prevenção Secundária
5.
Int J Pharm ; 564: 225-236, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31004716

RESUMO

At present, there is an increasing demand to improve the sustainability of surface-active compounds in dermal formulations. Biosurfactants, which are derived from living cells, are considered to be more environmentally friendly than synthetic surfactants. Thus, the use of biosurfactants is a promising strategy for the formulation of more environmentally friendly and sustainable dermal products. In this work, a biosurfactant extract (BS) obtained from corn wet-milling industry was studied for its potential use in dermal formulations. The corn derived BS possesses good surface-active properties and was found to be a suitable co-stabilizer for nanoemulsions and nanocrystals for dermal application. It also possesses antioxidative and skin protective properties and was also able to increase the dermal penetration efficacy for lipophilic actives. In dermal formulations the BS can therefore be used as co-stabilizer with antioxidative and penetration enhancing properties at the same time.


Assuntos
Antioxidantes/química , Tensoativos/química , Zea mays/química , Administração Cutânea , Animais , Antioxidantes/administração & dosagem , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Emulsões , Nanopartículas/administração & dosagem , Nanopartículas/química , Pele/efeitos dos fármacos , Pele/metabolismo , Tensoativos/administração & dosagem , Suínos , Molhabilidade
6.
Oncogene ; 36(21): 2981-2990, 2017 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-27941875

RESUMO

Type 2 transglutaminase (TG2) is an important cancer stem cell survival protein that exists in open and closed conformations. The major intracellular form is the closed conformation that functions as a GTP-binding GTPase and is required for cancer stem cell survival. However, at a finite rate, TG2 transitions to an open conformation that exposes the transamidase catalytic site involved in protein-protein crosslinking. The activities are mutually exclusive, as the closed conformation has GTP binding/GTPase activity, and the open conformation transamidase activity. We recently showed that GTP binding, but not transamidase activity, is required for TG2-dependent cancer stem cell invasion, migration and tumour formation. However, we were surprised that transamidase site-specific inhibitors reduce cancer stem cell survival. We now show that compounds NC9, VA4 and VA5, which react exclusively at the TG2 transamidase site, inhibit both transamidase and GTP-binding activities. Transamidase activity is inhibited by direct inhibitor binding at the transamidase site, and GTP binding is blocked because inhibitor interaction at the transamidase site locks the protein in the extended/open conformation to disorganize/inactivate the GTP binding/GTPase site. These findings suggest that transamidase site-specific inhibitors can inhibit GTP binding/signalling by driving a conformation change that disorganizes the TG2 GTP binding to reduce TG2-dependent signalling, and that drugs designed to target this site may be potent anti-cancer agents.


Assuntos
Aminoaciltransferases/antagonistas & inibidores , Antineoplásicos/farmacologia , Proteínas de Ligação ao GTP/antagonistas & inibidores , Proteínas de Ligação ao GTP/química , Guanosina Trifosfato/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/fisiologia , Transglutaminases/antagonistas & inibidores , Transglutaminases/química , Aminoaciltransferases/química , Sítios de Ligação/efeitos dos fármacos , Domínio Catalítico/efeitos dos fármacos , Domínio Catalítico/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Células Cultivadas , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Técnicas de Inativação de Genes , Humanos , Terapia de Alvo Molecular , Ligação Proteica/efeitos dos fármacos , Conformação Proteica/efeitos dos fármacos , Proteína 2 Glutamina gama-Glutamiltransferase , Transglutaminases/genética , Transglutaminases/metabolismo
7.
Oncogene ; 35(33): 4379-87, 2016 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-26804163

RESUMO

We identify a limited subpopulation of epidermal cancer stem cells (ECS cells), in squamous cell carcinoma, that form rapidly growing, invasive and highly vascularized tumors, as compared with non-stem cancer cells. These ECS cells grow as non-attached spheroids, and display enhanced migration and invasion. We show that ECS cell-produced vascular endothelial growth factor (VEGF)-A is required for the maintenance of this phenotype, as knockdown of VEGF-A gene expression or treatment with VEGF-A-inactivating antibody reduces these responses. In addition, treatment with bevacizumab reduces tumor vascularity and growth. Surprisingly, the classical mechanism of VEGF-A action via interaction with VEGF receptors does not mediate these events, as these cells lack VEGFR1 and VEGFR2. Instead, VEGF-A acts via the neuropilin-1 (NRP-1) co-receptor. Knockdown of NRP-1 inhibits ECS cell spheroid formation, invasion and migration, and attenuates tumor formation. These studies suggest that VEGF-A acts via interaction with NRP-1 to trigger intracellular events leading to ECS cell survival and formation of aggressive, invasive and highly vascularized tumors.


Assuntos
Células-Tronco Neoplásicas/fisiologia , Neuropilina-1/fisiologia , Neoplasias Cutâneas/patologia , Fator A de Crescimento do Endotélio Vascular/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular , Humanos , Invasividade Neoplásica , Receptores de Fatores de Crescimento do Endotélio Vascular/fisiologia , Neoplasias Cutâneas/irrigação sanguínea
9.
Cell Death Dis ; 6: e1647, 2015 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-25695600

RESUMO

Epidermal keratinocyte differentiation on the body surface is a carefully choreographed process that leads to assembly of a barrier that is essential for life. Perturbation of keratinocyte differentiation leads to disease. Activator protein 1 (AP1) transcription factors are key controllers of this process. We have shown that inhibiting AP1 transcription factor activity in the suprabasal murine epidermis, by expression of dominant-negative c-jun (TAM67), produces a phenotype type that resembles human keratoderma. However, little is understood regarding the structural and molecular changes that drive this phenotype. In the present study we show that TAM67-positive epidermis displays altered cornified envelope, filaggrin-type keratohyalin granule, keratin filament, desmosome formation and lamellar body secretion leading to reduced barrier integrity. To understand the molecular changes underlying this process, we performed proteomic and RNA array analysis. Proteomic study of the corneocyte cross-linked proteome reveals a reduction in incorporation of cutaneous keratins, filaggrin, filaggrin2, late cornified envelope precursor proteins, hair keratins and hair keratin-associated proteins. This is coupled with increased incorporation of desmosome linker, small proline-rich, S100, transglutaminase and inflammation-associated proteins. Incorporation of most cutaneous keratins (Krt1, Krt5 and Krt10) is reduced, but incorporation of hyperproliferation-associated epidermal keratins (Krt6a, Krt6b and Krt16) is increased. RNA array analysis reveals reduced expression of mRNA encoding differentiation-associated cutaneous keratins, hair keratins and associated proteins, late cornified envelope precursors and filaggrin-related proteins; and increased expression of mRNA encoding small proline-rich proteins, protease inhibitors (serpins), S100 proteins, defensins and hyperproliferation-associated keratins. These findings suggest that AP1 factor inactivation in the suprabasal epidermal layers reduces expression of AP1 factor-responsive genes expressed in late differentiation and is associated with a compensatory increase in expression of early differentiation genes.


Assuntos
Fator 1 Ativador da Transcrição/metabolismo , Queratinócitos/citologia , Queratinócitos/metabolismo , Fator 1 Ativador da Transcrição/genética , Animais , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células Epidérmicas , Epiderme/ultraestrutura , Feminino , Proteínas Filagrinas , Queratinócitos/ultraestrutura , Queratinas/metabolismo , Camundongos , Microscopia Eletrônica , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Proteômica , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo
10.
Cell Death Differ ; 22(5): 801-14, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25361079

RESUMO

The Wnt/ß-catenin signaling pathway has emerged as a key regulator of complex biological processes, such as embryonic development, cell proliferation, cell fate decision and tumorigenesis. Recent studies have shown that the deregulation of Wnt/ß-catenin signaling is frequently observed and leads to abnormal cell growth in human breast cancer cells. In this study, we identified a novel regulatory mechanism of Wnt/ß-catenin signaling through RARRES3 that targets and modulates the acylation status of Wnt proteins and co-receptor low-density lipoprotein receptor-related protein 6, resulting in the suppression of epithelial-mesenchymal transition and cancer stem cell properties. Mutation of the conserved active site residues of RARRES3 indicates that RARRES3 serves as an acyl protein thioesterase that tethers its target proteins and modulates their acylation status. Furthermore, the functions of p53 in cell proliferation and Wnt/ß-catenin signaling are significantly associated with the induction of RARRES3. Thus our findings provide a new insight into the molecular link between p53, protein acylation and Wnt/ß-catenin signaling whereby RARRES3 plays a pivotal role in modulating the acylation status of signaling proteins.


Assuntos
Neoplasias da Mama/metabolismo , Proliferação de Células , Transição Epitelial-Mesenquimal , Receptores do Ácido Retinoico/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Via de Sinalização Wnt , Acilação , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Humanos , Células MCF-7 , Receptores do Ácido Retinoico/genética , Proteína Supressora de Tumor p53/genética
11.
Ann Oncol ; 25(1): 9-15, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24335854

RESUMO

The number of cancer patients in Europe is rising and significant advances in basic and applied cancer research are making the provision of optimal care more challenging. The concept of cancer as a systemic, highly heterogeneous and complex disease has increased the awareness that quality cancer care should be provided by a multidisciplinary team (MDT) of highly qualified healthcare professionals. Cancer patients also have the right to benefit from medical progress by receiving optimal treatment from adequately trained and highly skilled medical professionals. Built on the highest standards of professional training and continuing medical education, medical oncology is recognised as an independent medical specialty in many European countries. Medical oncology is a core member of the MDT and offers cancer patients a comprehensive and systemic approach to treatment and care, while ensuring evidence-based, safe and cost-effective use of cancer drugs and preserving the quality of life of cancer patients through the entire 'cancer journey'. Medical oncologists are also engaged in clinical and translational research to promote innovation and new therapies and they contribute to cancer diagnosis, prevention and research, making a difference for patients in a dynamic, stimulating professional environment. Medical oncologists play an important role in shaping the future of healthcare through innovation and are also actively involved at the political level to ensure a maximum contribution of the profession to Society and to tackle future challenges. This position paper summarises the multifarious and vital contributions of medical oncology and medical oncologists to today's and tomorrow's professional cancer care.


Assuntos
Oncologia/educação , Neoplasias/terapia , Papel do Médico , Europa (Continente) , Medicina Baseada em Evidências , Humanos , Comunicação Interdisciplinar , Oncologia/normas , Neoplasias/diagnóstico , Relações Médico-Paciente , Qualidade da Assistência à Saúde
12.
Lung Cancer ; 80(3): 306-12, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23489557

RESUMO

INTRODUCTION: Some patients with advanced NSCLC show prolonged disease stabilization on treatment with an EGFR-tyrosine kinase inhibitor (TKI) such as erlotinib. It is not clear how to treat patients who progress after prolonged response to erlotinib. We hypothesized that TKI therapy beyond progression with added chemotherapy, radiotherapy or best supportive care may improve survival. PATIENTS AND METHODS: We retrospectively analyzed all NSCLC patients treated with erlotinib at our institutions since 2004who progressed after at least stable disease on erlotinib for at least 6 months. The first 16 patients did not receive further TKI treatment after progression (controls). The following 25 patients were treated with TKI beyond progression (TKI patients). Overall survival (OS) was analyzed for the whole population, a case-control analysis of pairs matched for gender, smoking status, and histology (n=28), and for patients with known EGFR mutation status (n=23). RESULTS: Treatment with TKI and chemotherapy was well tolerated. TKI-patients had a significantly longer OS from progression on TKI (case-control: median 14.5 vs. 2.0 months, HR 0.154) and longer OS from diagnosis of lung cancer (case-control: median 54.5 vs. 28.3 months, HR 0.474). An activating EGFR mutation was detected in 13 of the 23 patient tested (57%). Both among patients with and without detection of an activating EGFR mutation, those treated with erlotinib beyond progression had a longer survival. CONCLUSIONS: In our case-control analysis in long-term erlotinib responders, treatment with TKI beyond progression in addition to chemotherapy or radiotherapy was feasible and lead to prolonged overall survival.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/administração & dosagem , Quinazolinas/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Estudos de Casos e Controles , Terapia Combinada , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Cloridrato de Erlotinib , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/radioterapia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Inibidores de Proteínas Quinases/efeitos adversos , Quinazolinas/efeitos adversos
14.
Adv Dent Res ; 24(2): 94-7, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22899688

RESUMO

Streptococcus mutans has been implicated as the major acid-producing (cariogenic) bacterium. Dietary sugars and other factors may cause an imbalance of oral microflora that enables S. mutans to become dominant in the multi-species biofilms on the tooth surface, which could lead to dental caries. The application of broad-spectrum antimicrobials often results in re-colonization and re-dominance of S. mutans within oral flora, while in contrast, therapies capable of selective elimination of S. mutans from oral microbial communities may help to re-establish the normal flora and provide long-term protection. C16G2, a novel synthetic antimicrobial peptide with specificity for S. mutans, was found to have robust killing efficacy and selectivity for S. mutans in vitro. A subsequent pilot human study found that a single application of C16G2 in the oral cavity (formulated in a mouthrinse vehicle) was associated with a reduction in plaque and salivary S. mutans, lactic acid production, and enamel demineralization during the entire 4-day testing period. C16G2 is now being developed as a new anticaries drug.


Assuntos
Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Cárie Dentária/microbiologia , Streptococcus mutans/efeitos dos fármacos , Anti-Infecciosos/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Biofilmes/efeitos dos fármacos , Cárie Dentária/prevenção & controle , Placa Dentária/microbiologia , Humanos
15.
Caries Res ; 45(5): 415-28, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21860239

RESUMO

BACKGROUND/AIMS: Streptococcus mutans, the major etiological agent of dental caries, has a measurable impact on domestic and global health care costs. Though persistent in the oral cavity despite conventional oral hygiene, S. mutans can be excluded from intact oral biofilms through competitive exclusion by other microorganisms. This suggests that therapies capable of selectively eliminating S. mutans while limiting the damage to the normal oral flora might be effective long-term interventions to fight cariogenesis. To meet this challenge, we designed C16G2, a novel synthetic specifically targeted antimicrobial peptide with specificity for S. mutans. C16G2 consists of a S. mutans-selective 'targeting region' comprised of a fragment from S. mutans competence stimulation peptide (CSP) conjoined to a 'killing region' consisting of a broad-spectrum antimicrobial peptide (G2). In vitro studies have indicated that C16G2 has robust efficacy and selectivity for S. mutans, and not other oral bacteria, and affects targeted bacteria within seconds of contact. METHODS: In the present study, we evaluated C16G2 for clinical utility in vitro, followed by a pilot efficacy study to examine the impact of a 0.04% (w/v) C16G2 rinse in an intra-oral remineralization/demineralization model. RESULTS AND CONCLUSIONS: C16G2 rinse usage was associated with reductions in plaque and salivary S. mutans, lactic acid production, and enamel demineralization. The impact on total plaque bacteria was minimal. These results suggest that C16G2 is effective against S. mutans in vivo and should be evaluated further in the clinic.


Assuntos
Anti-Infecciosos/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Proteínas de Bactérias/uso terapêutico , Antissépticos Bucais/uso terapêutico , Streptococcus mutans/efeitos dos fármacos , Desmineralização do Dente/prevenção & controle , Adolescente , Adulto , Idoso , Animais , Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/síntese química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Proteínas de Bactérias/síntese química , Proteínas de Bactérias/farmacologia , Biofilmes/efeitos dos fármacos , Bovinos , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Placa Dentária/microbiologia , Placa Dentária/prevenção & controle , Gengiva/citologia , Gengiva/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Ácido Láctico/metabolismo , Meliteno/farmacologia , Pessoa de Meia-Idade , Mucosa Bucal/citologia , Mucosa Bucal/efeitos dos fármacos , Antissépticos Bucais/farmacologia , Projetos Piloto , Saliva/efeitos dos fármacos , Saliva/microbiologia , Especificidade da Espécie , Sacarose/metabolismo , Desmineralização do Dente/microbiologia , Remineralização Dentária/métodos , Adulto Jovem
16.
Domest Anim Endocrinol ; 40(3): 147-54, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21194874

RESUMO

The genes coding for H-FABP (heart acid-binding protein) and LEPR (leptin receptor) are considered to be candidates for lipid metabolism and thus affect fat deposition in pigs. The aim of our study was to assess the amount of H-FABP and LEPR transcript in the skeletal muscles (m. longissimus dorsi, m. semimembranosus) and liver of pigs of various ages. The experiments were carried out on 5 popular breeds of swine raised in Poland which exhibit different levels of fat tissue. Furthermore, we examined the effect of H-FABP and LEPR genotypes (HinfI, HpaII, and HaeIII for H-FABP and HpaII for LEPR) on the expression abundance of these genes. We confirmed a statistically significant relationship between the breed (P<.001), type of tissue (LEPR P<.001; H-FABP P<.01), and age of the animal (P<.05) on the abundance of mRNA transcript of both genes. In all breeds, the expression of the leptin receptor gene increased significantly (P<.01) with age in muscle tissue, whereas this relationship was not observed in liver tissue. However, the expression of the H-FABP gene in muscles did not change with age or breed, although in the liver expression levels were high in young (60 and 90 d) pigs. In conclusion, H-FABP and LEPR genes are strongly related to the development and function of fat tissue in pigs.


Assuntos
Proteínas de Ligação a Ácido Graxo/biossíntese , Fígado/fisiologia , Músculo Esquelético/fisiologia , Receptores para Leptina/biossíntese , Suínos/genética , Animais , Proteínas de Ligação a Ácido Graxo/genética , Feminino , Variação Genética , Genótipo , Modelos Lineares , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Músculo Esquelético/metabolismo , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores para Leptina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Suínos/metabolismo
17.
Gene Expr Patterns ; 11(1-2): 79-83, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20888930

RESUMO

The MyoD, Myf6 genes, which belong to the family of muscle regulatory factors (MRFs) play a major role in muscle growth and development. Therefore, they are considered as candidate genes for meat production traits in pigs. These basic helix-loop-helix (bHLH) transcription factors regulate myogenesis: they initiate the formation of muscle fibres and regulate the transcription of muscle specific genes. The paired-box transcription factor Pax7 plays critical roles during fetal development and this protein is essential for renewal and maintenance of muscle stem cells. In particular, expression of Pax7 and MyoD is correlated with presence of active satellite cells, important in hyperplastic and hypertrophic growth in skeletal muscle. The objective of the study was to investigate the level of expression of MyoD, Myf6 and Pax7 genes in porcine skeletal muscles (m. semimembranosus, m. biceps femoris, m. gracilis) in breeds differing in muscularity. Moreover, we investigated expression profile of these genes during ontogenesis in Polish Large White (PLW) and Pietrain pigs in the largest ham muscle (m.semimembranosus). Analysis of several ham muscles showed higher expression of MyoD in the Polish Landrace (PL) breed than in Pietrain and PLW pigs (m. semimembranosus P<0.001; m. biceps femoris P<0.05 and P<0.01, respectively; m. gracilisP<0.01). The level of Pax7 transcript depended on type of muscle and breed. The highest expression was in m. gracilis in Pietrain and the lowest in Polish Landrace. Our results indicate that MyoD and Pax7 genes had higher expression levels in the early stages of development in both investigated breeds. The total expression profile of MyoD and Pax7 genes suggests that higher muscularity in Pietrain pigs is associated with the presence of a greater number of active satellite stem cells compared to other breeds. The expression level of Myf6 gene does not indicate significant differences between muscles, ages and breeds.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Músculo Esquelético/metabolismo , Proteína MyoD/genética , Fatores de Regulação Miogênica/genética , Fator de Transcrição PAX7/genética , Sus scrofa/genética , Animais , Cruzamentos Genéticos , Feminino , Masculino , Carne , Especificidade da Espécie , Sus scrofa/metabolismo
18.
Gene Ther ; 18(3): 294-303, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20981110

RESUMO

In this study, we describe a simple system in which human keratinocytes can be redirected to an alternative differentiation pathway. We transiently transfected freshly isolated human skin keratinocytes with the single transcription factor OCT4. Within 2 days these cells displayed expression of endogenous embryonic genes and showed reduced genomic methylation. More importantly, these cells could be specifically converted into neuronal and contractile mesenchymal cell types. Redirected differentiation was confirmed by expression of neuronal and mesenchymal cell mRNA and protein, and through a functional assay in which the newly differentiated mesenchymal cells contracted collagen gels as efficiently as authentic myofibroblasts. Thus, to generate patient-specific cells for therapeutic purposes, it may not be necessary to completely reprogram somatic cells into induced pluripotent stem cells before altering their differentiation and grafting them into new tissues.


Assuntos
Diferenciação Celular/fisiologia , Queratinócitos/citologia , Fator 3 de Transcrição de Octâmero/metabolismo , Transfecção/métodos , Western Blotting , Linhagem Celular , Metilação de DNA , Primers do DNA/genética , Citometria de Fluxo , Humanos , RNA/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Oncogene ; 29(44): 5873-82, 2010 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-20818430

RESUMO

Activator protein one (AP1) (jun/fos) factors comprise a family of transcriptional regulators (c-jun, junB, junD, c-fos, FosB, Fra-1 and Fra-2) that are key controllers of epidermal keratinocyte survival and differentiation, and are important drivers of cancer development. Understanding the role of these factors in epidermis is complicated by the fact that each member is expressed in defined cell layers during epidermal differentiation, and because AP1 factors regulate competing processes (that is, proliferation, apoptosis and differentiation). We have proposed that AP1 factors function differently in basal versus suprabasal epidermis. To test this, we inactivated suprabasal AP1 factor function in mouse epidermis by targeted expression of dominant-negative c-jun (TAM67), which inactivates function of all AP1 factors. This produces increased basal keratinocyte proliferation, delayed differentiation and extensive hyperkeratosis. These findings contrast with previous studies showing that basal layer AP1 factor inactivation does not perturb resting epidermis. It is interesting that in spite of extensive keratinocyte hyperproliferation, susceptibility to carcinogen-dependent tumor induction is markedly attenuated. These novel observations strongly suggest that AP1 factors have distinct roles in the basal versus suprabasal epidermis, confirm that AP1 factor function is required for normal terminal differentiation, and suggest that AP1 factors have a different role in normal epidermis versus cancer progression.


Assuntos
Carcinógenos/toxicidade , Proliferação de Células , Epiderme/metabolismo , Neoplasias Experimentais/patologia , Dermatopatias/metabolismo , Fator de Transcrição AP-1/metabolismo , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Animais , Sequência de Bases , Primers do DNA , Camundongos , Camundongos Transgênicos , Neoplasias Experimentais/induzido quimicamente , Reação em Cadeia da Polimerase , Acetato de Tetradecanoilforbol/toxicidade
20.
Opt Express ; 18(9): 9722-7, 2010 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-20588821

RESUMO

Enhanced optical transmission (EOT) through a single aperture is usually achieved by exciting surface plasmon polaritons with periodic grooves. Surface plasmon polaritons are only excited by p-polarized incident light, i.e. with the electric field perpendicular to the direction of the grooves. The present study experimentally investigates EOT for s-polarized light. A subwavelength slit surrounded on each side by periodic grooves has been fabricated in a gold film and covered by a thin dielectric layer. The excitation of s-polarized dielectric waveguide modes inside the dielectric film strongly increases the s-polarized transmission. A 25 fold increase is measured as compared to the case without the dielectric film. Transmission measurements are compared with a coupled mode method and show good qualitative agreement. Adding a waveguide can improve light transmission through subwavelength apertures, as both s and p-polarization can be efficiently transmitted.

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