Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 179
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Clin Oral Implants Res ; 34(7): 719-726, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37248956

RESUMO

AIM: To assess in vitro the workflow for alveolar ridge augmentation with customised 3D printed block grafts and simultaneous computer-assisted implant planning and placement. METHODS: Twenty resin mandible models with an edentulous area and horizontal ridge defect in the region 34-36 were scanned with cone beam computed tomography (CBCT). A block graft for horizontal ridge augmentation in the region 34-36 and an implant in the position 35 were digitally planned. Twenty block grafts were 3D printed out of resin and one template for guided implant placement were stereolithographically produced. The resin block grafts were positioned onto the ridge defects and stabilised with two fixation screws each. Subsequently, one implant was inserted in the position 35 through the corresponding template for guided implant placement. Optical scans of the study models together with the fixated block graft were performed prior to and after implant placement. The scans taken after block grafting were superimposed with the virtual block grafting plan through a best-fit algorithm, and the linear deviation between the planned and the achieved block positions was calculated. The precision of the block fixation was obtained by superimposing the 20 scans taken after grafting and calculating the deviation between the corresponding resin blocks. The superimposition between the scans taken after and prior to implant placement was performed to measure a possible displacement in the block position induced by guided implant placement. The (98-2%)/2 percentile value was determined as a parameter for surface deviation. RESULTS: The mean deviation in the position of the block graft compared to the virtual plan amounted to 0.79 ± 0.13 mm. The mean deviation between the positions of the 20 block grafts measured 0.47 ± 0.2 mm, indicating a clinically acceptable precision. Guided implant placement induced a mean shift of 0.16 ± 0.06 mm in the position of the block graft. CONCLUSIONS: Within the limitations of this in vitro study, it can be concluded that customised block grafts fabricated through CBCT, computer-assisted design and 3D printing allow alveolar ridge augmentation with clinically acceptable predictability and reproducibility. Computer-assisted implant planning and placement can be performed simultaneously with computer-assisted block grafting leading to clinically non-relevant dislocation of block grafts.


Assuntos
Aumento do Rebordo Alveolar , Implantes Dentários , Cirurgia Assistida por Computador , Implantação Dentária Endóssea/métodos , Reprodutibilidade dos Testes , Desenho Assistido por Computador , Tomografia Computadorizada de Feixe Cônico , Cirurgia Assistida por Computador/métodos , Computadores , Aumento do Rebordo Alveolar/métodos , Transplante Ósseo/métodos
2.
Opt Express ; 28(22): 33456-33474, 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33115008

RESUMO

In this paper we present numerical and experimental results revealing that the mode instability threshold of highly Yb-doped, Ce/Al co-doped pedestal fibers is affected by the size of the index-increased pedestal structure surrounding the core. An alternative preparation technology for the realization of large mode area fibers with very large Al-doped silica pedestals is introduced. Three different pedestal fiber design iterations characterized by low photodarkening were manufactured and tested in counter-pumped amplifier setups. Up to 1.9 kW continuous-wave output power of near-diffraction-limited beam quality (M2 = 1.26) was achieved with an 18/200/420 µm fiber of very low NA = 0.042, limited only by the occurrence of mode instabilities.

3.
Int J Obes (Lond) ; 41(6): 945-954, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28220039

RESUMO

BACKGROUND: Treatment with estrogen in early menopausal women protects against development of hepatic steatosis and nonalcoholic fatty liver disease but estrogen has undesirable side effects, which negate its beneficial effects in premenopausal and postmenopausal women. Targeted therapies require better understanding of the target sites and mechanisms by which estrogen signaling exerts its protective effects in women. Estrogen receptor α (ERα) is thought to be the primary mediator for estrogen signaling to protect against hepatic steatosis. ERα has several mechanisms for signal transduction: (1) inducing gene transcription by direct binding to specific DNA sequences, (2) inducing tethered transcription with other DNA-binding factors, and (3) stimulating nongenomic action through membrane-associated ERα. However, it is still unclear which mechanisms mediate ERα-dependent protection against hepatic steatosis. METHODS: To understand the mechanisms of estrogen signaling for protection against hepatic steatosis in females, we analyzed the global ERα knockout mouse (αERKO), ERα DNA-binding domain mutant mouse (KIKO) and liver-specific ERα knockout mouse (LERKO) fed high-fat diets (HFD). The KIKO mouse disrupts the direct DNA-binding transcription activity but retains tethered transcription regulation and nongenomic action. Hepatic steatosis was evaluated by scoring the macrovesicular and microvesicular steatosis as well as serum alanine aminotransferase (ALT) levels. We analyzed serum testosterone to assess its correlation with hepatic steatosis. RESULTS: Liver fat accumulation was far greater in HFD-fed αERKO and KIKO females than in HFD-fed wild-type (WT) controls. Conversely, HFD-fed LERKO females did not accumulate excess liver fat. HFD-fed αERKO and KIKO females showed higher microvesicular steatosis and ALT levels than WT controls that correlated with increased serum testosterone levels. CONCLUSIONS: ERα-mediated direct transcription in non-hepatic tissues is essential for estrogen-mediated protection against hepatic steatosis in HFD-fed females. The balance between non-hepatic estrogen signaling and hepatic or non-hepatic testosterone action may control hepatic steatosis.


Assuntos
Receptor alfa de Estrogênio/genética , Estrogênios/farmacologia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Adiposidade , Animais , Western Blotting , Proteínas de Ligação a DNA/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Estrogênios/administração & dosagem , Feminino , Camundongos , Camundongos Knockout , Fatores de Transcrição/efeitos dos fármacos
5.
Rev Med Suisse ; 11(466): 657-8, 660-2, 2015 Mar 18.
Artigo em Francês | MEDLINE | ID: mdl-25962227

RESUMO

Osteogenesis imperfecta (OI) is a rare genetic disease. Today we are able to propose an adapted and efficient management to the patients with this rare disorder (and their families) thanks to a strong collaboration of clinicians and researchers. Recent knowledge regarding the genetics of OI permits an accurate diagnosis of the specific type of OI and its own molecular mechanism, a genetic counseling for family planning and prenatal diagnosis, and in addition more targeted therapeutic options. A specific support with re-education for patients with OI is necessary and efficient. To optimize patient care, a multidisciplinary consultation is proposed at the CHUV, moreover a web site is available for patients, families and therapists: www.infomaladiesrares.ch


Assuntos
Osteogênese Imperfeita/terapia , Assistência ao Paciente/métodos , Diagnóstico Pré-Natal/métodos , Feminino , Aconselhamento Genético/métodos , Humanos , Comunicação Interdisciplinar , Osteogênese Imperfeita/diagnóstico , Osteogênese Imperfeita/genética , Educação de Pacientes como Assunto/métodos , Gravidez
6.
Opt Lett ; 39(9): 2763-6, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24784097

RESUMO

A dual-core fiber in which one of the cores is doped with germanium and the other with phosphorus is used as an in-line Mach-Zehnder dispersive interferometer. By ensuring an equal length but with different dispersion dependencies in the interferometer arms (the two cores), high-sensitivity strain and temperature sensing are achieved. Opposite sensitivities for high and low wavelength peaks were also demonstrated when strain and temperature was applied. To our knowledge this is the first time that such behavior is demonstrated using this type of in-line interferometer based on a dual-core fiber. A sensitivity of (0.102±0.002) nm/µÎµ, between 0 and 800 µÎµ and (-4.2±0.2) nm/°C between 47°C and 62°C is demonstrated.

7.
J Dent Res ; 102(13): 1452-1459, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37944556

RESUMO

Machine learning (ML) models, especially deep neural networks, are increasingly being used for the analysis of medical images and as a supporting tool for clinical decision-making. In this study, we propose an artificial intelligence system to facilitate dental decision-making for the removal of mandibular third molars (M3M) based on 2-dimensional orthopantograms and the risk assessment of such a procedure. A total of 4,516 panoramic radiographic images collected at the Center of Dental Medicine at the University of Zurich, Switzerland, were used for training the ML model. After image preparation and preprocessing, a spatially dependent U-Net was employed to detect and retrieve the region of the M3M and inferior alveolar nerve (IAN). Image patches identified to contain a M3M were automatically processed by a deep neural network for the classification of M3M superimposition over the IAN (task 1) and M3M root development (task 2). A control evaluation set of 120 images, collected from a different data source than the training data and labeled by 5 dental practitioners, was leveraged to reliably evaluate model performance. By 10-fold cross-validation, we achieved accuracy values of 0.94 and 0.93 for the M3M-IAN superimposition task and the M3M root development task, respectively, and accuracies of 0.9 and 0.87 when evaluated on the control data set, using a ResNet-101 trained in a semisupervised fashion. Matthew's correlation coefficient values of 0.82 and 0.75 for task 1 and task 2, evaluated on the control data set, indicate robust generalization of our model. Depending on the different label combinations of task 1 and task 2, we propose a diagnostic table that suggests whether additional imaging via 3-dimensional cone beam tomography is advisable. Ultimately, computer-aided decision-making tools benefit clinical practice by enabling efficient and risk-reduced decision-making and by supporting less experienced practitioners before the surgical removal of the M3M.


Assuntos
Dente Serotino , Dente Impactado , Humanos , Dente Serotino/diagnóstico por imagem , Dente Serotino/cirurgia , Inteligência Artificial , Odontólogos , Dente Impactado/cirurgia , Extração Dentária , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Papel Profissional , Dente Molar , Aprendizado de Máquina , Radiografia Panorâmica/métodos , Tomografia Computadorizada de Feixe Cônico , Nervo Mandibular/diagnóstico por imagem
8.
Prev Vet Med ; 213: 105860, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36724618

RESUMO

Metabolic diseases driven by negative energy balance in dairy cattle contribute to reduced milk production, increased disease incidence, culling, and death. Cow side tests for negative energy balance markers are available but are labor-intensive. Milk sample analysis using Fourier transform infrared spectroscopy (FTIR) allows for sampling numerous cows simultaneously. FTIR prediction models have moderate accuracy for hyperketonemia diagnosis (beta-hydroxybutyrate (BHB) ≥ 1.2 mmol/L). Most research using FTIR has focused on homogenous datasets and conventional prediction models, including partial least squares, linear discriminant analysis, and ElasticNet. Our objective was to evaluate more diverse modeling options, such as deep learning, gradient boosting machine models, and model ensembles for hyperketonemia classification. We compiled a sizable, heterogeneous dataset including milk FTIR and concurrent blood samples. Blood samples were tested for blood BHB, and wavenumber data was obtained from milk FTIR analysis. Using this dataset, we trained conventional prediction models and other options listed above. We demonstrate prediction model performance is similar for convolutional neural networks and ensemble models to simpler algorithm options. Results obtained from this study indicate that deep learning and model ensembles are potential algorithm options for predicting hyperketonemia in dairy cattle. Additionally, our results indicate hyperketonemia prediction models can be developed using heterogeneous datasets.


Assuntos
Doenças dos Bovinos , Cetose , Feminino , Bovinos , Animais , Leite/química , Espectroscopia de Infravermelho com Transformada de Fourier/veterinária , Cetose/veterinária , Ácido 3-Hidroxibutírico , Lactação
10.
J Med Genet ; 47(10): 704-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20577006

RESUMO

BACKGROUND: Mutations in TRPV4, a gene that encodes a Ca(2+) permeable non-selective cation channel, have recently been found in a spectrum of skeletal dysplasias that includes brachyolmia, spondylometaphyseal dysplasia, Kozlowski type (SMDK) and metatropic dysplasia (MD). Only a total of seven missense mutations were detected, however. The full spectrum of TRPV4 mutations and their phenotypes remained unclear. OBJECTIVES AND METHODS: To examine TRPV4 mutation spectrum and phenotype-genotype association, we searched for TRPV4 mutations by PCR-direct sequencing from genomic DNA in 22 MD and 20 SMDK probands. RESULTS: TRPV4 mutations were found in all but one MD subject. In total, 19 different heterozygous mutations were identified in 41 subjects; two were recurrent and 17 were novel. In MD, a recurrent P799L mutation was identified in nine subjects, as well as 10 novel mutations including F471del, the first deletion mutation of TRPV4. In SMDK, a recurrent R594H mutation was identified in 12 subjects and seven novel mutations. An association between the position of mutations and the disease phenotype was also observed. Thus, P799 in exon 15 is a hot codon for MD mutations, as four different amino acid substitutions have been observed at this codon; while R594 in exon 11 is a hotspot for SMDK mutations. CONCLUSION: The TRPV4 mutation spectrum in MD and SMDK, which showed genotype-phenotype correlation and potential functional significance of mutations that are non-randomly distributed over the gene, was presented in this study. The results would help diagnostic laboratories establish efficient screening strategies for genetic diagnosis of the TRPV4 dysplasia family diseases.


Assuntos
Mutação , Osteocondrodisplasias/genética , Osteocondrodisplasias/patologia , Canais de Cátion TRPV/genética , Análise Mutacional de DNA , Nanismo/diagnóstico por imagem , Nanismo/genética , Nanismo/patologia , Genótipo , Humanos , Mutação de Sentido Incorreto , Osteocondrodisplasias/diagnóstico por imagem , Fenótipo , Reação em Cadeia da Polimerase , Radiografia , Análise de Sequência de DNA
11.
Clin Genet ; 77(3): 266-72, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20447141

RESUMO

Stüve-Wiedemann syndrome (SWS, OMIM 601559) is a severe autosomal recessive condition caused by mutations in the leukemia inhibitory receptor (LIFR) gene. The main characteristic features are bowing of the long bones, neonatal respiratory distress, swallowing/sucking difficulties and dysautonomia symptoms including temperature instability often leading to death in the first years of life. We report here four patients with SWS who have survived beyond 36 months of age with no LIFR mutation. These patients have been compared with six unreported SWS survivors carrying null LIFR mutations. We provide evidence of clinical homogeneity of the syndrome in spite of the genetic heterogeneity.


Assuntos
Anormalidades Múltiplas/genética , Heterogeneidade Genética , Osteocondrodisplasias/genética , Anormalidades Múltiplas/fisiopatologia , Feminino , Seguimentos , Genes Recessivos , Humanos , Subunidade alfa de Receptor de Fator Inibidor de Leucemia/genética , Masculino , Osteocondrodisplasias/fisiopatologia , Síndrome
12.
J Med Genet ; 46(8): 562-8, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19508970

RESUMO

BACKGROUND: Schneckenbecken dysplasia (SBD) is an autosomal recessive lethal skeletal dysplasia that is classified into the severe spondylodysplastic dysplasias (SSDD) group in the international nosology for skeletal dysplasias. The radiological hallmark of SBD is the snail-like configuration of the hypoplastic iliac bone. SLC35D1 (solute carrier-35D1) is a nucleotide-sugar transporter involved in proteoglycan synthesis. Recently, based on human and mouse genetic studies, we showed that loss-of-function mutations of the SLC35D1 gene (SLC35D1) cause SBD. OBJECT: To explore further the range of SLC35D1 mutations in SBD and elucidate whether SLC35D1 mutations cause other skeletal dysplasias that belong to the SSDD group. METHODS AND RESULTS: We searched for SLC35D1 mutations in five families with SBD and 15 patients with other SSDD group diseases, including achodrogenesis type 1A, spondylometaphyseal dysplasia Sedaghatian type and fibrochondrogenesis. We identified four novel mutations, c.319C>T (p.R107X), IVS4+3A>G, a 4959-bp deletion causing the removal of exon 7 (p.R178fsX15), and c.193A>C (p. T65P), in three SBD families. Exon trapping assay showed IVS4+3A>G caused skipping of exon 4 and a frameshift (p.L109fsX18). Yeast complementation assay showed the T65P mutant protein lost the transporter activity of nucleotide sugars. Therefore, all these mutations result in loss of function. No SLC35D1 mutations were identified in all patients with other SSDD group diseases. CONCLUSION: Our findings suggest that SLC35D1 loss-of-function mutations result consistently in SBD and are exclusive to SBD.


Assuntos
Doenças do Desenvolvimento Ósseo/genética , Doenças Fetais/genética , Deleção de Genes , Proteínas de Transporte de Monossacarídeos/genética , Mutação , Sequência de Bases , Clonagem Molecular , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Nucleotídeos/metabolismo , Reação em Cadeia da Polimerase , Gravidez , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência
13.
Eur Respir J ; 33(4): 785-92, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19129292

RESUMO

Pulmonary hypertension (PH) is associated with impaired production of the vasodilator nitric oxide (NO). Riociguat (BAY 63-2521; Bayer Healthcare AG, Wuppertal, Germany) acts directly on soluble guanylate cyclase, stimulating the enzyme and increasing sensitivity to low NO levels. The present study evaluates riociguat safety, tolerability and efficacy in patients with moderate-to-severe PH (pulmonary arterial hypertension, distal chronic thromboembolic PH or PH with mild to moderate interstitial lung disease). The optimal tolerated dose was identified by incremental dosing in four patients with PH; pharmacodynamic and pharmacokinetic parameters were assessed following single-dose administration (2.5 mg or 1 mg) in 10 and five patients with PH, respectively. All subjects (n = 19) were analysed for safety and tolerability. Riociguat had a favourable safety profile at single doses < or =2.5 mg. It significantly improved pulmonary haemodynamic parameters and cardiac index in patients with PH in a dose-dependent manner, to a greater extent than inhaled NO. Although riociguat also had significant systemic effects and showed no pulmonary selectivity, mean systolic blood pressure remained >110 mmHg. The present report is the first to describe the use of riociguat in patients with pulmonary hypertension. The drug was well-tolerated and superior to nitric oxide in efficacy and duration. Riociguat, therefore, has potential as a novel therapy for pulmonary hypertension and warrants further investigation.


Assuntos
Guanilato Ciclase/biossíntese , Guanilato Ciclase/fisiologia , Pirimidinas/farmacologia , Receptores Citoplasmáticos e Nucleares/biossíntese , Receptores Citoplasmáticos e Nucleares/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Área Sob a Curva , Cromatografia Líquida de Alta Pressão , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/enzimologia , Hipertensão Pulmonar/fisiopatologia , Masculino , Pessoa de Meia-Idade , Óxido Nítrico Sintase Tipo II/farmacologia , Oxirredução , Circulação Pulmonar/fisiologia , Pirimidinas/farmacocinética , Guanilil Ciclase Solúvel , Resultado do Tratamento
14.
Science ; 219(4582): 257-9, 1983 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-17798255

RESUMO

Executive Order 12356, signed by President Reagan on 2 April 1982, prescribes a system for classifying information on the basis of national security concerns. The order gives unprecedented authority to government officials to intrude at will in controlling academic research that depends on federal support. As such, it poses a serious threat to academic freedom and hence to scientific advances and the national security.

15.
Am J Med Genet A ; 146A(9): 1185-9, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18351627

RESUMO

Holt-Oram syndrome (HOS) (OMIM 142900) is characterized by upper-extremity malformations involving the radial, thenar, or carpal bones and a personal and/or family history of congenital heart defects (CHDs). It is inherited in an autosomal dominant manner. The TBX5 gene located on chromosome 12 (12q24.1) is the only gene currently known to be associated with HOS and is associated with variable phenotypes. We report on the clinical and molecular characterization of a HOS family with three affected individuals and a novel mutation (Lys88ter). We discuss genotype-phenotype correlations, the presence of foot anomalies in one affected individual, and the role of atypical features in HOS differential diagnosis.


Assuntos
Anormalidades Múltiplas/genética , Deformidades Congênitas do Pé/genética , Cardiopatias Congênitas/genética , Deformidades Congênitas das Extremidades Superiores/genética , Anormalidades Múltiplas/patologia , Adolescente , Adulto , Códon sem Sentido , Análise Mutacional de DNA , Feminino , Deformidades Congênitas do Pé/patologia , Humanos , Masculino , Linhagem , Síndrome , Proteínas com Domínio T/genética , Deformidades Congênitas das Extremidades Superiores/patologia
16.
Opt Express ; 15(11): 6894-9, 2007 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-19547003

RESUMO

Fiber waveguide arrays can be applied as a very useful tool for the investigation of effects in discrete optics. The observation of coherent propagation in such discrete waveguide arrays requires, however, high structural precision and great material homogeneity. The fabrication of such a fiber array with close tolerances compared to conventional fiber technology is discussed. Linear propagation effects are modeled for an ideal fiber waveguide array and are compared with experimental results. The good agreement of these results with each other indicates the applicability of such fiber waveguide arrays in studying linear and non-linear properties in discrete optics.

17.
Int J Clin Pharmacol Ther ; 44(5): 216-24, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16724576

RESUMO

OBJECTIVES: To investigate the pharmacodynamic effects of the combined administration of vardenafil and ethanol on blood pressure and heart rate and to study the mutual pharmacokinetic interaction, safety and tolerability of the combination. METHODS: 12 healthy male subjects aged 18 - 45 years received 3 different single-dose treatments in a randomized, double-blind, placebo-controlled crossover design: 20 mg vardenafil plus 0.5 g/kg ethanol, vardenafil plus placebo and ethanol plus placebo. Heart rate (HR) as well as systolic (SBP) and diastolic blood pressure (DBP) were measured in supine position after 15 min of rest at 0.25, 0.5, 0.75, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 10, 12, 15 and 24 h post dosing using a validated oscillometric sphygmomanometer. Vardenafil, vardenafil metabolite M-1 and ethanol pharmacokinetics were assessed. RESULTS: There were no statistically significant differences between treatments in DBP and SBP. Significantly higher increases in HR were seen when the combination vardenafil/ethanol and ethanol/placebo treatment, respectively, was compared with vardenafil/placebo treatment. The difference between the 2 treatments including ethanol, however, was not significant. All hemodynamic changes were not clinically relevant. The pharmacokinetics of vardenafil and ethanol were not changed in the treatment "vardenafil + ethanol" compared to the respective treatment with vardenafil and ethanol alone. The most frequently reported adverse events were vasodilation and nasal congestion, well-known side effects of PDE-5 inhibitors such as vardenafil. CONCLUSION: Concomitant administration of vardenafil and alcohol was well-tolerated. No clinically relevant pharmacodynamic or pharmacokinetic interactions were detected.


Assuntos
Depressores do Sistema Nervoso Central/farmacocinética , Etanol/farmacocinética , Imidazóis/farmacocinética , Inibidores de Fosfodiesterase/farmacocinética , Piperazinas/farmacocinética , Administração Oral , Adulto , Pressão Sanguínea/efeitos dos fármacos , Depressores do Sistema Nervoso Central/administração & dosagem , Interações Medicamentosas , Etanol/administração & dosagem , Frequência Cardíaca/efeitos dos fármacos , Humanos , Imidazóis/administração & dosagem , Masculino , Inibidores de Fosfodiesterase/administração & dosagem , Piperazinas/administração & dosagem , Sulfonas/administração & dosagem , Sulfonas/farmacocinética , Triazinas/administração & dosagem , Triazinas/farmacocinética , Dicloridrato de Vardenafila
18.
Cancer Res ; 43(9): 4504-10, 1983 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6871879

RESUMO

The monocyte-macrophage system has long been recognized as a necessary accessory to the immune response. Recently, however, monocyte-macrophages have been shown to be important effectors of cell-mediated cellular cytotoxicity (both antibody dependent and antibody independent). In this study, monocyte-mediated cellular cytotoxicity of both types was assessed on 51Cr-labeled human erythrocytes (type B+) using autologous and standardized AB serum, and monocytes from 57 normal controls, 16 women with benign breast disease, and 175 patients with cancers of the breast (44 patients), colorectum (46 patients), head and neck (33 patients), lung (13 patients), and melanoma (39 patients). Although results were variable, many of the patients had depressed antibody-dependent cellular cytotoxicity suggesting decreased ability of their monocyte-macrophage to lyse the sensitized erythrocytes. Enhanced antibody-dependent cellular cytotoxicity was observed in patients with localized colorectal cancer, but this effect was reversed in patients with advanced disease. Serum factors did not significantly affect responses in most cases. The clinical relevance of this assay remains to be determined.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos , Citotoxicidade Imunológica , Hemólise , Monócitos/imunologia , Neoplasias da Mama/imunologia , Adesão Celular , Eritrócitos/imunologia , Feminino , Neoplasias de Cabeça e Pescoço/imunologia , Humanos , Neoplasias Intestinais/imunologia , Neoplasias Pulmonares/imunologia , Macrófagos/imunologia , Melanoma/imunologia , Neoplasias/imunologia , Valores de Referência
19.
Oncogene ; 11(2): 291-301, 1995 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-7542763

RESUMO

Inactivation of the tumour suppressor gene lethal(2) giant larvae (D-lgl) of Drosophila leads to malignant transformation of the presumptive adult optic centers in the larval brain and tumours of the imaginal discs. These malignancies result from the disorganization of a cytoskeletal network in which the D-LGL protein participates. Here we describe the isolation of a cDNA encoding the human homologue to the D-lgl gene designated as hugl. The hugl cDNA detects a locus spanning at least 25 kilobases (kb) in human chromosome band 17p11.2-12, which is centromeric to the p53 gene and recognizes a 4.5 kb RNA transcript. The hugl gene is expressed in brain, kidney and muscle but is barely seen in heart and placenta. Sequence analysis of the hugl cDNA demonstrates a long open reading frame, which has the potential to encode a protein of 1057 amino acids with a predicted molecular weight of 115 kDaltons (kD). To further substantiate and identify the HUGL protein, we have prepared polyclonal rabbit antibodies against synthetic peptides corresponding to the amino and carboxyl termini of the conceptual translation product of the hugl gene. The affinity-purified anti-HUGL antibodies recognize a single protein with an apparent molecular weight of approximately 115 kD. Similar to the Drosophila protein, HUGL is part of a cytoskeletal network and, is associated with nonmuscle myosin II heavy chain and a kinase that specifically phosphorylates HUGL at serine residues.


Assuntos
Cromossomos Humanos Par 17 , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/genética , Drosophila/genética , Genes Supressores de Tumor , Miosinas/genética , Proteínas , Sequência de Aminoácidos , Animais , Sequência de Bases , Evolução Biológica , Northern Blotting , Mapeamento Cromossômico , Sequência Conservada , Proteínas do Citoesqueleto/imunologia , DNA Complementar , Regulação da Expressão Gênica , Genes de Insetos , Humanos , Rim/fisiologia , Camundongos , Dados de Sequência Molecular , Músculo Esquelético/fisiologia , Miosinas/química , Placenta/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , RNA , Homologia de Sequência de Aminoácidos
20.
J Mol Biol ; 221(3): 1015-26, 1991 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-1658331

RESUMO

The 1H nuclear magnetic resonance spectral characteristics of the cyano-Met form of Chironomus thummi thummi monomeric hemoglobins I, III and IV in 1H2O solvent are reported. A set of four exchangeable hyperfine-shifted resonances is found for each of the two heme-insertion isomers in the hyperfine-shifted region downfield of ten parts per million. An analysis of relaxation, exchange rates and nuclear Overhauser effects leads to assignments for all these resonances to histidine F8 and the side-chains of histidine E7 and arginine FG3. It is evident that in aqueous solution, the side-chain from histidine E7 does not occupy two orientations, as found for the solid state, rather the histidine E7 side-chain adopts a conformation similar to that of sperm whale myoglobin or hemoglobin A, oriented into the heme pocket and in contact with the bound ligand. Evidence is presented to show that the allosteric transition in the Chironomus thummi thummi hemoglobins arises from the "trans effect". An analysis of the exchange with bulk solvent of the assigned histidine E7 labile proton confirms that the group is completely buried within the heme pocket in a manner similar to that found for sperm whale cyano-Met myoglobin, and that the transient exposure to solvent is no more likely than in mammalian myoglobins with the "normal" distal histidine orientation. Finally, a comparison of solvent access to the heme pocket of the three monomeric C. thummi thummi hemoglobins, as measured from proton exchange rates of heme pocket protons, is made and correlated to binding studies with the diffusible small molecules such as O2.


Assuntos
Chironomidae/química , Histidina/química , Metemoglobina/análogos & derivados , Animais , Heme/química , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Metemoglobina/química , Conformação Proteica , Prótons , Soluções , Temperatura , Termodinâmica , Água
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA