Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 160
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Graefes Arch Clin Exp Ophthalmol ; 258(1): 129-135, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31754827

RESUMO

PURPOSE: Visual acuity (VA) is an important determinant of visual function. Here we establish procedures and recommendations for VA testing extending beyond the classical VA and thus make them available for future studies of visual function in health and disease. Specifically, we provide reference values for photopic and scotopic conventional uncrowded visual acuity (cVA) and Vernier-hyperacuity (hVA) and assess their reproducibility and dependence on contrast polarity. METHODS: For ten observers with normal vision, we determined photopic ("p"; maximal luminance 220 cd/m2) and scotopic ("s"; maximal luminance 0.004 cd/m2; 40 min of dark adaptation) cVA and hVA, for two contrast polarities i.e. black optotypes on white background and vice versa. To assess intersession effects, two sets of measurements were obtained on different days. RESULTS: Compared to pcVA (1.32 decimal VA; - 0.12 ± 0.02 LogMAR), the phVA (14.45 decimal VA; - 1.16 ± 0.04 LogMAR) scaled (in terms of decimal visual acuity) on average with a factor 11.0, the scVA (0.12 decimal VA; 0.91 ± 0.03 LogMAR) with a factor of 0.1, and the shVA (1.47 decimal VA; - 0.17 ± 0.02 LogMAR) with a factor of 1.1. There were neither significant effects of contrast polarity (p > 0.12), nor of session (p > 0.28). CONCLUSIONS: Our approach optimises integrated photopic and scotopic cVA and hVA measurements for general use and thus encourages the integration of these important measures of scotopic visual function in future studies. The absence of strong intersession effects demonstrates that no dedicated training session is needed to obtain scotopic and hVA measurements. The combined measures of scotopic and photopic VAs open a field of applications to study interplay and plasticity of the retinal photoreceptor systems and cortical processing in health and visual disease. As a rule of thumb, hyperacuity is 10× higher both in the photopic and scotopic range than conventional acuity. Thus, scotopic hyperacuity is close to photopic conventional acuity.


Assuntos
Visão de Cores/fisiologia , Adaptação à Escuridão/fisiologia , Transtornos da Visão/diagnóstico , Acuidade Visual , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa , Reprodutibilidade dos Testes , Transtornos da Visão/fisiopatologia , Testes Visuais/métodos , Adulto Jovem
2.
Odontology ; 108(4): 607-616, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32030565

RESUMO

The aim of this study was to analyse the effect of cold atmospheric plasma (CAP) on human osteoblast-like cells in vitro. Additionally, underlying intracellular mechanisms were to be studied. Human osteoblast-like (MG63) cells were exposed to CAP for 60 s. The effects of CAP on key molecules essential for the wound healing response were studied using real-time PCR, ELISA and immunocytochemistry. For studying intracellular signalling pathways, MAP kinase MEK 1/2 was blocked. Cell viability was analysed by an XTT assay and with an EVE automated cell counter. Cell migration was examined by an in vitro wound healing assay.CAP exposition on osteoblast-like cells caused a significant upregulation of interleukin (IL)-1ß, IL-6, IL-8, tumor necrosis factor (TNF)α, cyclooxygenase (COX)2, collagen (COL) 1α, matrix metalloproteinase (MMP)1, Ki67, proliferating-cell-nuclear-antigen (PCNA) and chemokine ligand (CCL)2 mRNA expression at 1 day. Interestingly, after blocking of MAP kinase, CAP-induced upregulation of Ki67 was inhibited by 57%. Moreover, CAP treatment improved significantly osteoblast-like cell viability as compared to untreated cells at 1 day. Beneficial effect of CAP treatment was shown by an in vitro wound healing assay, displaying a significant faster wound closure. Our findings provide evidence that CAP exposure effects gene and protein regulation in human osteoblast-like cells. Furthermore, CAP treatment has a positive impact on wound closure in an in vitro setting and might improve existing concepts of hard tissue regeneration in the future.


Assuntos
Gases em Plasma , Movimento Celular , Colágeno , Humanos , Osteoblastos , Cicatrização
3.
Clin Oral Investig ; 19(5): 1121-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25346374

RESUMO

OBJECTIVES: Cancer progression is influenced by tumor microenvironment and communication of stromal cells and tumor cells. Interactions may enhance epithelial-mesenchymal transition (EMT) of tumor cells through signaling proteins such as Wnt/beta-catenin and matrix metalloproteinases (MMP), as well as loss of cellular integrity, which affects invasion, progression, and metastasis of head and neck squamous cell carcinoma (HNSCC). In this study, we are testing the hypothesis that interactions of human mesenchymal stromal cells (MSCs) with HNSCC might influence the expression of markers of EMT and tumor progression by co-culturing human MSC with the PCI-13 HNSCC line. MATERIALS AND METHODS: Pooled MSCs were derived from the iliac bone marrow of seven patients and co-cultured in transwell permeable membrane wells with tumor cells of the established HNSCC cell line PCI-13 (UICC: T3, N1, M0). MSCs were characterized through fluorescence-activated cell sorting (FACS) analysis. Expression of Wnt3, E-cadherin, beta-catenin, MMP14, cathepsin b, and ETS1 was assessed by quantitative RT-PCR. RESULTS: We were able to show that co-culture of MSCs and PCI-13 leads to a significantly reduced expression of Wnt3, MMP14, and beta-catenin compared to controls, whereas the expression of cathepsin b and ETS1 was not significantly different between co-cultures and controls. CONCLUSION: Our results suggest that the interaction between MSCs and PCI-13 may suppress EMT in cancer cells. CLINICAL RELEVANCE: The influence of MSCs can suppress the onset of EMT in HNSCC, affecting tumor progression and therapy.


Assuntos
Carcinoma de Células Escamosas/patologia , Transição Epitelial-Mesenquimal , Neoplasias de Cabeça e Pescoço/patologia , Células-Tronco Mesenquimais/fisiologia , Adolescente , Adulto , Biomarcadores Tumorais/análise , Linhagem Celular Tumoral , Criança , Técnicas de Cocultura , Progressão da Doença , Citometria de Fluxo , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Carcinoma de Células Escamosas de Cabeça e Pescoço
4.
Rev Sci Instrum ; 95(9)2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39254432

RESUMO

Many modern accelerators rely on superconducting radio-frequency (SRF) cavities to accelerate particles. When these cavities are cooled to the superconducting state, a fraction of the ambient magnetic field (e.g., Earth's magnetic field) may be trapped in the superconductor. This trapped flux can significantly increase the power dissipation of the SRF cavities. It is, therefore, crucial to understand the underlying mechanism of how magnetic flux is trapped and what treatments and operating conditions can reduce the flux-trapping efficiency. A new experiment was designed that enables a systemic investigation of flux trapping. It allows for independent control of cooldown conditions, which might have an influence on flux trapping: temperature gradient across the superconductor during cooldown, cooldown rate, and ambient magnetic field. For exhaustive studies, the setup was designed for quick thermal cycling, permitting up to 300 superconducting transitions in one day. In this paper, the setup and operation is described in detail and an estimation of the measurement errors is given. Exemplary data are presented to illustrate the efficacy of the system.

5.
J Craniomaxillofac Surg ; 50(11): 817-824, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36376159

RESUMO

The aim of this study was the development of a statistical model for reliable prediction of Posterior Airway Space (PAS) changes in lateral cephalograms (LCR) of patients after bimaxillary orthognathic surgery. The LCRs of patients who underwent bimaxillary orthognathic surgery were retrospectively analyzed. The anteroposterior dimension of the PAS was measured at three levels in the pre-operative and postoperative LCR: On the nasopharyngeal (SPAS), oropharyngeal (MAS), and hypopharyngeal level (IAS). The data of 139 patients were collected. The following changes of the PAS were measured: in class II patients SPAS: 0.291 mm (SD = 2.570 mm); MAS: 2.444 mm (SD = 2.986 mm); IAS: 0.750 mm (SD = 3.017 mm); in class III patients SPAS: 1.377 mm (SD 3.212 mm); MAS: 0.962 (SD: = 3.135 mm); IAS: 0.370 mm (SD = 3.468 mm). Linear regression analysis showed for class II patients, a significant influence of mandibular movement on MAS (p = 0.049) and a significant effect of maxillary and mandibular movements on SPAS (p = 0.001) and MAS (p = 0.022) in class III patients. The other jaw displacements had no significant impact on the investigated PAS levels. While the presented method does not permit exact prediction of the dimension of the PAS, it is still an easily accessible method of orientation for the surgeon. The surgeon can initiate three-dimensional examinations to provide exact three-dimensional prediction based on this calculation.


Assuntos
Má Oclusão Classe III de Angle , Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Humanos , Estudos Retrospectivos , Procedimentos Cirúrgicos Ortognáticos/métodos , Má Oclusão Classe III de Angle/cirurgia , Cefalometria/métodos , Faringe/diagnóstico por imagem , Modelos Teóricos
6.
Carcinogenesis ; 32(3): 434-42, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21173432

RESUMO

A role of WNT signaling for primary breast cancers of the basal-like subtype and as a predictor of brain metastasis has been described. However, a responsible WNT ligand has not been identified. To further clarify this question, we comparatively investigated 22 human breast cancer brain metastases as well as the highly invasive human breast cancer cell line MDA-MB-231 and the weakly motile MCF-7 as models for the basal-like and the luminal A subtype. WNT5A and B were found overexpressed in MDA-MB-231 cells as compared with MCF-7. This corresponded to reduction of MDA-MB-231 invasiveness by WNT inhibitors, whereas MCF-7 invasion was enhanced by recombinant WNT5B and abolished by WNT and Jun-N-terminal kinase antagonists. Expression and subcellular distribution of ß-catenin remained uninfluenced. Consistently, ß-catenin was not localized in the nuclei of brain metastases while there was strong nuclear c-Jun staining. Similar to MDA-MB-231, metastases showed expression of WNT5A/B and the alternative WNT receptors ROR1 and 2. These findings were validated using external gene expression datasets (Gene Expression Omnibus) of different breast cancer subtypes and brain metastases. Hierarchical cluster analysis yielded a close relation between basal-like cancers and brain metastases. Gene set enrichment analyses confirmed WNT pathway enrichment not only in basal-like primaries but also in cerebral metastases of all subtypes. In conclusion, WNT signaling seems highly relevant for basal-like and other subtypes of breast cancers metastasizing into the brain. ß-catenin-independent WNT signaling, presumably via ROR1-2, plays a major role in this context.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias da Mama/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Wnt/genética , beta Catenina/genética , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/secundário , Neoplasias da Mama/patologia , Carcinoma Basocelular/genética , Carcinoma Basocelular/patologia , Adesão Celular , Movimento Celular , Proliferação de Células , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Wnt-5a
7.
Artigo em Alemão | MEDLINE | ID: mdl-22143561

RESUMO

Vector-transmitted diseases are one of the major contributors to the global burden of disease in humans and animals. Climate change is consistently held responsible for the spread of parasitic acarid and insect vectors such as ticks, fleas, sand flies and mosquitoes, and their transmitted pathogens (in the case of the dog the so-called canine vector-borne diseases [CVBD]). Currently, there is only insufficient data available to prove whether climate change is a major driving force for vector and disease expansion, but the evidence is growing. Other reasons, such as ecological, demographic and socio-economic factors, e.g. pet travel into and pet import from endemic areas, also play a role in this development. Apart from all the controversial discussion of the factors leading to vector and disease expansion, preventative measures should include dog owners' education as they are responsible for individual parasite protection as well as for the minimisation of adverse risk behaviour, e.g. regarding pet travel. Broad-spectrum vector control should be practised by using parasiticides that repel and kill blood feeders in order to minimize the risk of CVBD-pathogen transmission.


Assuntos
Mudança Climática , Doenças Transmissíveis/veterinária , Vetores de Doenças , Doenças do Cão/etiologia , Animais , Doenças Transmissíveis/epidemiologia , Doenças Transmissíveis/etiologia , Doenças Transmissíveis/transmissão , Doenças do Cão/epidemiologia , Doenças do Cão/transmissão , Cães , Viagem
8.
J Small Anim Pract ; 62(8): 669-676, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33739459

RESUMO

OBJECTIVES: The aims of this retrospective study were to report the short- and long-term outcome in cats treated for pyothorax and to identify prognostic indicators as well as determine recurrence rate. METHODS: Medical records from April 2009 to August 2018 were retrospectively reviewed. Cases were included if a diagnosis of pyothorax was confirmed via cytology and/or culture of pleural fluid. Cats diagnosed with or suspected of having other thoracic diseases and cats with no evidence of pleural effusion were excluded from the study. RESULTS: Fifty-five cats met the inclusion criteria. Eighty five percent (n=47) cats underwent medical management with thoracostomy tubes, pleural lavage and broad-spectrum antibiotics. Fifteen percent (n=5) cases failed medical treatment and underwent thoracotomy. Twenty eight percent (n=13) did not survive to hospital discharge. Short-term survival (14 days) was achieved in 72% (n=34). Long-term follow-up was available for 31 of 34 with a long-term survival rate of 68% (n=30). The recurrence rate was 6% (n=2). CONCLUSION: For cats with pyothorax that survive to discharge the prognosis is excellent and the condition is associated with a low recurrence rate.


Assuntos
Doenças do Gato , Empiema Pleural , Derrame Pleural , Animais , Doenças do Gato/diagnóstico , Doenças do Gato/terapia , Gatos , Empiema Pleural/cirurgia , Empiema Pleural/veterinária , Derrame Pleural/cirurgia , Derrame Pleural/veterinária , Prognóstico , Estudos Retrospectivos , Toracotomia/veterinária , Resultado do Tratamento
9.
Ann Anat ; 231: 151517, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32229241

RESUMO

PURPOSE: Periodontal ligament (PDL) cell cultures are classically maintained in serum-containing media. However, unwanted side-effects of these conditions on cellular and molecular characteristics demand a serum-free alternative. Even though these limitations are well known and efforts for the development of adequate serum-free alternatives have been made, these approaches for replacement remained unsuccessful so far. This study aimed at developing a well-defined, serum-free formulation supporting both isolation from tissue samples and efficient expansion of PDL cells. Here, of particular focus was the perpetuation of tissue-characteristic markers detectable in primary tissues and of stemness features. BASIC PROCEDURES: Primary PDL cell cultures from generally healthy human donors (n = 3) were maintained in basal media N2B27 and E6 together with different concentrations of growth and attachment factors. Cell proliferation was recorded via microscopy and WST assay. Gene expression of RUNX2, Periostin, ALP, CD73, CD90, CD105, CD45, SOX10 and SOX2 was compared to primary PDL explants via qRT-PCR. Immunocytochemistry was performed for anti-CD105, SSEA-3, CD271, HNK1. Serum-containing sDMEM medium served as control. MAIN FINDINGS: N2B27 medium substituted with 25 ng/mL EGF, 25 ng/mL IGF1, 0.5 mg/mL Fetuin plus gelatine coating (designated N2B27-PDLsf) emerged as potent serum-free formulation ensuring adequate culture isolation and expansion. Here, PDL primary tissue signature markers RUNX2 and Periostin remained stable in N2B27-PDLsf compared to controls (229.0-fold ±101.0 and 83.2-fold ±9.6 increase). Additionally, stemness markers ALP and CD105 were significantly upregulated on transcriptional, and CD105 and SOX2 on protein level. PRINCIPAL CONCLUSIONS: This investigation identified a novel serum-free medium for the isolation, and expansion of primary human PDL cells with constantly high proliferation rates. Here, purity and stemness properties are maintained. Thus, N2B27-PDLsf represents a valid replacement for serum-containing media in PDL cultures.


Assuntos
Biomarcadores/análise , Meios de Cultura Livres de Soro , Ligamento Periodontal/citologia , Fosfatase Alcalina/análise , Fosfatase Alcalina/genética , Análise de Variância , Moléculas de Adesão Celular/análise , Moléculas de Adesão Celular/genética , Proliferação de Células , Subunidade alfa 1 de Fator de Ligação ao Core/análise , Subunidade alfa 1 de Fator de Ligação ao Core/genética , DNA Complementar/biossíntese , Feminino , Humanos , Imuno-Histoquímica , Masculino , Ligamento Periodontal/química , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação
10.
Clin Neurophysiol ; 130(3): 379-387, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30677707

RESUMO

OBJECTIVE: To investigate the scope of scotopic multifocal visual evoked potentials (mfVEPS) for the assessment of scotopic visual fields. METHODS: Pattern-reversal mfVEP for photopic (mfVEPP) and scotopic conditions (mfVEPS; 0.003 cd/m2) were recorded from 36 visual field locations of a circular checkerboard pattern (25° radius) in 9 participants with normal vision. MfVEPP were recorded with a conventional central fixation cross, mfVEPS were recorded (i) with (mfVEPS+) and (ii) without (mfVEPS-) an additional fixation aid. Latency shifts were determined using cross-correlations, mfVEP magnitudes were analysed in an eccentricity dependent manner using signal-to-noise ratios (SNRs). RESULTS: In comparison to mfVEPP, mfVEPS- and mfVEPS+ were delayed by 101 ms and 97 ms, respectively, and had smaller signal-to-noise-ratios. Both mfVEPS were reduced down to noise level in the center and also severely reduced for the most peripheral stimulus eccentricity used. The visual-field-coverage for the paracentral eccentricities of mfVEPS+ and mfVEPS- was 76% and 65% [4°-9°], respectively, and 79% and 66% [9°-16°]. CONCLUSIONS: MfVEPS were delayed compared to mfVEPP and demonstrated the expected central response drop-out typical for scotopic vision. SIGNIFICANCE: MfVEPS may hold promise of an objective, spatially resolved visual field test which motivates testing it in patients with diseases affecting scotopic vision.


Assuntos
Potenciais Evocados Visuais/fisiologia , Visão Noturna/fisiologia , Córtex Visual/fisiologia , Campos Visuais/fisiologia , Vias Visuais/fisiologia , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Estimulação Luminosa , Adulto Jovem
11.
Physiol Behav ; 92(4): 575-82, 2007 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-17585971

RESUMO

In rats, dietary supplementation with the amino acid tyrosine (TYR) prevents depletion of central catecholamines observed during acute environmental stress. Concomitant changes in the animals' behavioral responses to stress suggest that TYR might have similar effects on central catecholamines and cognition in humans exposed to environmental stress. This study aimed to determine if severe cold exposure impairs human cognition and if dietary supplementation with TYR would ameliorate such deficits. Volunteers (N=19) completed three test sessions on different days (35 degrees C control/placebo, approximately 10 degrees C/placebo, approximately 10 degrees C/TYR) using a double-blind, within subjects design. During each session, volunteers completed two 90-minute water immersions and consumed a food bar (150 mg/kg TYR or placebo) before each immersion (total TYR 300 mg/kg). Cognitive performance, mood, and salivary cortisol were assessed. Cortisol was elevated in the cold (p<.01). Volunteers made fewer correct responses on a Match-to-Sample memory measure (p<.05) and reaction time (RT) and errors increased on a choice RT test (p<.01) in the cold. Self-reported tension (p<.01), depression (p<.05) and confusion (p<.01) also increased in the cold. When volunteers consumed TYR, correct responses increased on a Match-to-Sample memory measure (p<.05) and study time for the sample was shorter (p<.05), indicative of more rapid and accurate information processing. Finally, RT on the memory measure revealed a similar pattern across immersions for TYR and thermoneutral conditions, but not cold/placebo (p<.05). This study demonstrates cold exposure degrades cognitive performance and supplementation with TYR alleviates working memory decrements.


Assuntos
Cognição/efeitos dos fármacos , Memória de Curto Prazo/efeitos dos fármacos , Tempo de Reação/efeitos dos fármacos , Estresse Fisiológico/metabolismo , Tirosina/metabolismo , Adaptação Fisiológica/efeitos dos fármacos , Adolescente , Adulto , Análise de Variância , Temperatura Corporal , Cognição/fisiologia , Temperatura Baixa , Suplementos Nutricionais , Aprendizagem por Discriminação/efeitos dos fármacos , Aprendizagem por Discriminação/fisiologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Tempo de Reação/fisiologia , Valores de Referência , Tirosina/farmacologia
12.
Nat Biotechnol ; 14(3): 303-8, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9630890

RESUMO

We have developed novel nucleic acid probes that recognize and report the presence of specific nucleic acids in homogeneous solutions. These probes undergo a spontaneous fluorogenic conformational change when they hybridize to their targets. Only perfectly complementary targets elicit this response, as hybridization does not occur when the target contains a mismatched nucleotide or a deletion. The probes are particularly suited for monitoring the synthesis of specific nucleic acids in real time. When used in nucleic acid amplification assays, gene detection is homogeneous and sensitive, and can be carried out in a sealed tube. When introduced into living cells, these probes should enable the origin, movement, and fate of specific mRNAs to be traced.


Assuntos
Corantes Fluorescentes , Sondas Moleculares , Hibridização de Ácido Nucleico , Sequência de Bases , Biotecnologia , Primers do DNA/genética , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Sondas Moleculares/síntese química , Sondas Moleculares/química , Estrutura Molecular , Naftalenossulfonatos/síntese química , Naftalenossulfonatos/química , Reação em Cadeia da Polimerase , p-Dimetilaminoazobenzeno/análogos & derivados , p-Dimetilaminoazobenzeno/síntese química , p-Dimetilaminoazobenzeno/química
13.
Nat Biotechnol ; 18(11): 1191-6, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11062440

RESUMO

We describe wavelength-shifting molecular beacons, which are nucleic acid hybridization probes that fluoresce in a variety of different colors, yet are excited by a common monochromatic light source. The twin functions of absorption of energy from the excitation light and emission of that energy in the form of fluorescent light are assigned to two separate fluorophores in the same probe. These probes contain a harvester fluorophore that absorbs strongly in the wavelength range of the monochromatic light source, an emitter fluorophore of the desired emission color, and a nonfluorescent quencher. In the absence of complementary nucleic acid targets, the probes are dark, whereas in the presence of targets, they fluoresce-not in the emission range of the harvester fluorophore that absorbs the light, but rather in the emission range of the emitter fluorophore. This shift in emission spectrum is due to the transfer of the absorbed energy from the harvester fluorophore to the emitter fluorophore by fluorescence resonance energy transfer, and it only takes place in probes that are bound to targets. Wavelength-shifting molecular beacons are substantially brighter than conventional molecular beacons that contain a fluorophore that cannot efficiently absorb energy from the available monochromatic light source. We describe the spectral characteristics of wavelength-shifting molecular beacons, and we demonstrate how their use improves and simplifies multiplex genetic analyses.


Assuntos
Transferência de Energia , Corantes Fluorescentes/química , Técnicas Genéticas , Sondas de Oligonucleotídeos/metabolismo , Alelos , Ligação Competitiva , Polarização de Fluorescência , Genótipo , Humanos , Hibridização de Ácido Nucleico , Sondas de Oligonucleotídeos/química , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA/métodos , Espectrometria de Fluorescência/métodos
14.
Nat Biotechnol ; 16(1): 49-53, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9447593

RESUMO

Molecular beacons are hairpin-shaped oligonucleotide probes that report the presence of specific nucleic acids in homogenous solutions. When they bind to their targets they undergo a conformational reorganization that restores the fluorescence of an internally quenched fluorophore. We found that their hairpin conformation enables the use of a wide variety of differently colored fluorophores. Using several molecular beacons, each designed to recognize a different target and each labeled with a different fluorophore, we demonstrate that multiple targets can be distinguished in the same solution, even if they differ from one another by as little as a single nucleotide. A comparison of "hairpin probes" with corresponding "linear probes" confirms that the presence of the hairpin stem in molecular beacons significantly enhances their specificity.


Assuntos
Alelos , Mutação/genética , Sondas de Oligonucleotídeos , Primers do DNA , Corantes Fluorescentes , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase , Espectrometria de Fluorescência , p-Dimetilaminoazobenzeno/análogos & derivados
15.
Nat Biotechnol ; 16(4): 359-63, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9555727

RESUMO

We developed a new approach to DNA sequence analysis that uses fluorogenic reporter molecules--molecular beacons--and demonstrated their ability to discriminate alleles in real-time PCR assays of genomic DNA. A set of overlapping molecular beacons was used to analyze an 81-bp region of the Mycobacterium tuberculosis rpoB gene for mutations that confer resistance to the antibiotic rifampin. In a blinded study of 52 rifampin-resistant and 23 rifampin-susceptible clinical isolates, this method correctly detected mutations in all of the resistant strains and in none of the susceptible strains. The assay was carried out entirely in sealed PCR tubes and was simple to perform and interpret. This approach can be used to analyze any DNA sequence of moderate length with single base pair accuracy.


Assuntos
Resistência Microbiana a Medicamentos/genética , Mycobacterium tuberculosis/efeitos dos fármacos , Mutação Puntual , Antibióticos Antituberculose/farmacologia , RNA Polimerases Dirigidas por DNA , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/genética , Proteínas de Plantas/genética , Reação em Cadeia da Polimerase , Rifampina/farmacologia
16.
Eur J Med Res ; 12(1): 13-20, 2007 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-17363353

RESUMO

The circulating hormonal form of human parathyroid hormone (hPTH-1-37) has been assessed in vitro as well as in vivo in the ovariectomized rat, a model for postmenopausal osteoporosis. In vitro, hPTH-1-37 induces a dose-dependent cAMP formation and increases vitality as well as alkaline phosphatase activity in UMR106 osteosarcoma cells. Differentiation and proliferation of osteoclasts in rat bone marrow-derived stem cell preparations are decreased. Daily hPTH-1-37 s.c. administration in ovariectomized rats for 60 days results in augmented formation of new bone, in amplified femural bone density, and in thickening of the calvaria.


Assuntos
Osteoporose Pós-Menopausa/tratamento farmacológico , Hormônio Paratireóideo/uso terapêutico , Fragmentos de Peptídeos/uso terapêutico , Fosfatase Alcalina/metabolismo , Análise de Variância , Animais , Linhagem Celular Tumoral , AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Feminino , Fêmur/diagnóstico por imagem , Fêmur/efeitos dos fármacos , Fêmur/crescimento & desenvolvimento , Humanos , Ovariectomia , Hormônio Paratireóideo/farmacologia , Fragmentos de Peptídeos/farmacologia , Radiografia , Ratos , Ratos Wistar , Crânio/efeitos dos fármacos , Crânio/crescimento & desenvolvimento
17.
Int J Oral Maxillofac Surg ; 36(12): 1146-52, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17822884

RESUMO

Most parents are emotionally traumatized when confronted by the birth of a baby with an orofacial cleft (OFC). Affected families may have to compensate for increased financial, social and personal impacts before primary treatment is completed. This study was conducted to identify factors influencing the quality of life (QoL) of families having young children with OFC. A self-administered questionnaire containing the impact on family scale was applied in 130 consecutive families having children with OFC aged between 6 and 24 months. The results were related to the type of cleft and the time of initial diagnosis using non-parametric tests and multivariate correlation analysis (P<0.05). In families having children with isolated cleft lip, financial and social impacts were reduced, but problems in coping were increased when compared to families with children having cleft lip and palate or isolated cleft palate. Total impact was highest in families having children with isolated cleft palate, probably due to later surgery for reconstruction. Prenatal diagnosis of OFC did not reduce the general impact on affected families, but increased the social impact. The relation of certain impacts to distinct types of cleft might allow more tailored support of affected families and improve their QoL.


Assuntos
Fenda Labial/psicologia , Fissura Palatina/psicologia , Família/psicologia , Qualidade de Vida/psicologia , Ultrassonografia Pré-Natal/psicologia , Adulto , Pré-Escolar , Fenda Labial/diagnóstico , Fissura Palatina/diagnóstico , Métodos Epidemiológicos , Pai/psicologia , Feminino , Humanos , Lactente , Masculino , Mães/psicologia , Gravidez
18.
Int J Oral Maxillofac Surg ; 36(1): 54-61, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16965899

RESUMO

The aim of this pilot study was to investigate the potential of calcium phosphate cement in the treatment of orbital wall defect fractures in an adult sheep model, and to compare this alloplastic material to autologous calvaria split-bone grafts. Clinical, volumetric and histological examinations were carried out of both reconstruction materials. The use of cement made intraoperative corrections easier to perform, and increased the precision of reconstruction of the orbital volume. This material also proved to be osseoconductive. The two materials were used successfully in combination. Regions of most intensive remodelling were the anterior orbital floor and the adjacent orbital rim. The preliminary results of this study demonstrate the potential of calcium phosphate cement as a useful biomaterial in the reconstruction of the anterior orbital region. Further animal and clinical trials are necessary to investigate its ability as a carrier for mediators where bone healing requires influence or support.


Assuntos
Cimentos Ósseos/uso terapêutico , Regeneração Óssea/efeitos dos fármacos , Órbita/cirurgia , Fraturas Orbitárias/cirurgia , Animais , Materiais Biocompatíveis/farmacologia , Cimentos Ósseos/química , Cimentos Ósseos/farmacologia , Transplante Ósseo , Fosfatos de Cálcio/farmacologia , Feminino , Modelos Animais , Projetos Piloto , Procedimentos de Cirurgia Plástica/métodos , Ovinos , Cirurgia Assistida por Computador
19.
Aviat Space Environ Med ; 78(5 Suppl): B268-75, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17547328

RESUMO

INTRODUCTION: Limited opportunities to study human cognitive performance in non-laboratory, ambulatory situations exist. However, advances in technology make it possible to extend behavioral assessments to the field. One of the first devices to measure human behavior in the field was the wrist-worn actigraph. This device acquires minute-by-minute information on an individual's physical activity and can distinguish sleep from waking, the most basic aspect of behavior. METHODS: Our laboratory developed a series of wrist-worn devices, not much larger than a watch, which assess reaction time, vigilance and memory. The devices concurrently assess motor activity with greater temporal resolution than standard actigraphs. They also continuously monitor multiple environmental variables including temperature, humidity, sound, and light. RESULTS: These monitors have been employed during training and simulated military operations to collect behavioral and environmental information that would typically be unavailable under such circumstances. Development of the vigilance monitor, and how each successive version extended capabilities of the device are described. Data from several studies are presented, including studies conducted in harsh field environments during a simulated infantry assault, an officer training course. DISCUSSION: The monitors simultaneously documented environmental conditions, patterns of sleep and activity and effects of nutritional manipulations on cognitive performance. They provide a new method to relate cognitive performance to real world environmental conditions and assess effects of various interventions on human behavior in the field. They can also monitor cognitive performance in real time, and if it is degraded, attempt to intervene to maintain


Assuntos
Atenção/fisiologia , Cognição/fisiologia , Militares , Monitorização Fisiológica/instrumentação , Desenho de Equipamento , Humanos , Memória/fisiologia , Tempo de Reação/fisiologia , Processamento de Sinais Assistido por Computador
20.
J Craniomaxillofac Surg ; 45(5): 731-740, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28318921

RESUMO

OBJECTIVES: TGF-ß1 signaling modulates epithelial mesenchymal transitions (EMT) of head and neck squamous cell carcinoma (HNSCC). Bone marrow mesenchymal stromal cells (BMSC) are able to exert a regulating influence on the expression of markers of EMT in HNSCC cells. It was thus the aim of this study to test the hypothesis that TGF-ß1 modulates the interactions of tumor transition between BMSCs and HNSCC, affecting the expression of E-cadherin, Vimentin, Snail, Twist, MMP14 and beta-catenin. Furthermore, we analyzed alterations in the AKT-signaling of tumor and stroma cells. MATERIALS AND METHODS: BMSCs were isolated from iliac bone marrow aspirates and co-cultured in trans-well permeable membrane wells with tumor cells of the established HNSCC cell line PCI-13. Following the induction with TGF-ß1 under serum free conditions the expression of Vimentin and E-Cadherin was assessed via immunofluorescence. A quantitative RT-PCR analysis of tumor transition markers E-cadherin, Vimentin, Snail, Twist, MMP14 and beta-catenin was performed. Changes in AKT-Signaling were identified via protein analysis. RESULTS: In non-induced co-cultures, BMSC were able to suppress Vimentin in PCI-13 as a marker of tumor transition. In TGF-ß1 induced co-cultures PCI-13 significantly increased the expression of Vimentin, Twist, Snail, MMP14, GSK3a, PRAS40, 4E-BP1, and AMPKa compared to monolayer controls. TGF-ß1 co-cultured BMSC demonstrated a significant increase of Snail, PRAS40, mTOR, GSK3a/b, Bad, PDK1 and 4E-BP1. CONCLUSIONS: TGF-ß1 was able to attenuate the modulating influence of BMSC in co-culture and drive the co-culture towards a progressive tumor transition, affecting the expression of markers of EMT, AKT-Signaling and proliferative checkpoints.


Assuntos
Transformação Celular Neoplásica/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Neoplasias Bucais/patologia , Fator de Crescimento Transformador beta1/farmacologia , Adolescente , Adulto , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Criança , Técnicas de Cocultura , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Pessoa de Meia-Idade , Neoplasias Bucais/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA