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1.
Lab Chip ; 20(10): 1792-1806, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32314760

RESUMO

Recent progress in the field of human induced pluripotent stem cells (iPSCs) has led to the efficient production of human neuronal cell models for in vitro study. This has the potential to enable the understanding of live human cellular and network function which is otherwise not possible. However, a major challenge is the generation of reproducible neural networks together with the ability to interrogate and record at the single cell level. A promising aid is the use of biomaterial scaffolds that would enable the development and guidance of neuronal networks in physiologically relevant architectures and dimensionality. The optimal scaffold material would need to be precisely fabricated with submicron resolution, be optically transparent, and biocompatible. Two-photon polymerisation (2PP) enables precise microfabrication of three-dimensional structures. In this study, we report the identification of two biomaterials that support the growth and differentiation of human iPSC-derived neural progenitors into functional neuronal networks. Furthermore, these materials can be patterned to induce alignment of neuronal processes and enable the optical interrogation of individual cells. 2PP scaffolds with tailored topographies therefore provide an effective method of producing defined in vitro human neural networks for application in influencing neurite guidance and complex network activity.


Assuntos
Células-Tronco Pluripotentes Induzidas , Orientação de Axônios , Materiais Biocompatíveis , Diferenciação Celular , Humanos , Neurônios , Alicerces Teciduais
2.
Ann Oncol ; 29(12): 2348-2355, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30346475

RESUMO

Background: The presence of mutated KRAS (mutKRAS ctDNA) in plasma samples has been consistently shown to be a negative prognostic indicator in pancreatic cancer (PC). Only small pilot studies have evaluated the value of serial mutKRAS ctDNA-measurements in PC. Patients and methods: The aim of the present study was to explore the potential of repeated mutKRAS ctDNA measurements for response prediction and therapy monitoring in advanced PC patients. We used the BEAMing technology to determine levels of mutKRAS ctDNA, CA 19-9, CEA and CYFRA 21-1 in 284 plasma samples of 54 patients with advanced PC receiving gemcitabine-based chemotherapy. Absolute levels and kinetics of mutKRAS ctDNA, CA 19-9, CEA and CYFRA 21-1 were correlated to radiological response, progression-free and overall survival. Results: mutKRAS ctDNA was present in a majority of advanced PC patients (n = 36/54, 67%) and indicated tissue KRAS mutation status with a high sensitivity (75%) and specificity (100%). The presence of mutKRAS ctDNA, as well as higher levels of CA 19-9, CEA and CYFRA 21-1 before initiation of the first-line chemotherapy, was significantly correlated to an adverse overall survival. During therapy, changes in mutKRAS ctDNA levels were more rapid and pronounced than changes in protein-based tumor markers. A decrease in mutKRAS ctDNA levels during therapy was an early indicator of response to therapy, while there was no significant correlation between kinetics of CA 19-9, CEA or CYFRA 21-1 and response to chemotherapy during the first four weeks of treatment. Repeated mutKRAS ctDNA measurements during follow-up appeared to be superior to protein-based tumor markers in detecting progressive disease (sensitivity: 83%, specificity: 100%). Conclusion: mutKRAS ctDNA kinetics appear to be a powerful and highly specific tool in early response prediction and therapy monitoring of advanced PC patients receiving chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/sangue , DNA Tumoral Circulante/sangue , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/tratamento farmacológico , Proteínas Proto-Oncogênicas p21(ras)/genética , Idoso , DNA Tumoral Circulante/genética , Desoxicitidina/uso terapêutico , Progressão da Doença , Monitoramento de Medicamentos/métodos , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Cuidados Paliativos/métodos , Pâncreas/patologia , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/mortalidade , Prognóstico , Intervalo Livre de Progressão , Estudos Prospectivos , Critérios de Avaliação de Resposta em Tumores Sólidos , Gencitabina
3.
Opt Express ; 25(1): 39-58, 2017 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-28085810

RESUMO

Here we present a new generic opto-bio-sensing platform combining immobilised aptamers on an infrared plasmonic sensing device generated by nano-structured thin film that demonstrates amongst the highest index spectral sensitivities of any optical fibre sensor yielding on average 3.4 × 104 nm/RIU in the aqueous index regime (with a figure of merit of 330) This offers a single stage, solution phase, atto-molar detection capability, whilst delivering real-time data for kinetic studies in water-based chemistry. The sensing platform is based upon optical fibre and has the potential to be multiplexed and used in remote sensing applications. As an example of the highly versatile capabilities of aptamer based detection using our platform, purified thrombin is detected down to 50 attomolar concentration using a volume of 1mm3 of solution without the use of any form of enhancement technique. Moreover, the device can detect nanomolar levels of thrombin in a flow cell, in the presence of 4.5% w/v albumin solution. These results are important, covering all concentrations in the human thrombin generation curve, including the problematic initial phase. Finally, selectivity is confirmed using complementary and non-complementary DNA sequences that yield performances similar to those obtained with thrombin.


Assuntos
Técnicas Biossensoriais/instrumentação , Fibras Ópticas , Trombina/análise , Humanos , Cinética
4.
J Clin Microbiol ; 54(3): 576-84, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26677254

RESUMO

Despite the current reliance on blood cultures (BCs), the diagnosis of bloodstream infections (BSIs) can be sped up using new technologies performed directly on positive BC bottles. Two methods (the MALDI BioTyper system and FilmArray blood culture identification [BCID] panel) are potentially applicable. In this study, we performed a large-scale clinical evaluation (1,585 microorganisms from 1,394 BSI episodes) on the combined use of the MALDI BioTyper and FilmArray BCID panel compared to a reference (culture-based) method. As a result, the causative organisms of 97.7% (1,362/1,394) of the BSIs were correctly identified by our MALDI BioTyper and FilmArray BCID-based algorithm. Specifically, 65 (5.3%) out of 1,223 monomicrobial BCs that provided incorrect or invalid identifications with the MALDI BioTyper were accurately detected by the FilmArray BCID panel; additionally, 153 (89.5%) out of 171 polymicrobial BCs achieved complete identification with the FilmArray BCID panel. Conversely, full use of the MALDI BioTyper would have resulted in the identification of only 1 causative organism in 97/171 (56.7%) of the polymicrobial cultures. By applying our diagnostic algorithm, the median time to identification was shortened (19.5 h versus 41.7 h with the reference method; P < 0.001), and the minimized use of the FilmArray BCID panel led to a significant cost savings. Twenty-six out of 31 microorganisms that could not be identified were species/genera not designed to be detected with the FilmArray BCID panel, indicating that subculture was not dispensable for a few of our BSI episodes. In summary, the fast and effective testing of BC bottles is realistically adoptable in the clinical microbiology laboratory workflow, although the usefulness of this testing for the management of BSIs remains to be established.


Assuntos
Sangue/microbiologia , Técnicas Microbiológicas/métodos , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase/métodos , Sepse/diagnóstico , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Algoritmos , Humanos , Técnicas Microbiológicas/economia , Técnicas de Diagnóstico Molecular/economia , Estudos Prospectivos , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/economia , Fatores de Tempo
5.
Vet Med (Auckl) ; 7: 149-155, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-30050847

RESUMO

Lameness in beef and dairy cattle is responsible for economic losses and has significant animal welfare implications. It has been proposed that early treatment with analgesics not only reduces acute pain but also leads to reduced long-term sensitization. Fifty-three cattle (309-954 kg body weight [BW], mean: 656 kg) with musculoskeletal lameness were scored for lameness and inflammation, then randomly assigned to a single oral treatment with meloxicam oral suspension (MOS) (28 animals) at 1 mg/kg or saline at 1 mL/15 kg BW. Lameness and inflammation were reevaluated 3 days after treatment, and 26 of 28 (92.8%) MOS-treated animals had a reduced lameness score, while only three of 25 control animals had a reduced lameness score. MOS was effective in treating musculoskeletal disease in cattle. In an accompanying residue depletion study, 22 lactating Holstein cows (BW: 553-927 kg, mean: 713 kg) were used in the study. All 22 animals received MOS at the dose of 1 mg/kg BW once. Milk (500 mL sample from the full milking volume) was collected at approximately 48, 72, 96, and 120 hours after the treatment. Samples were subjected to in vitro analysis for quantification of meloxicam by liquid chromatography and mass spectroscopy. The mean meloxicam concentration at 48 and 72 hours were 30.75 and 2.82 ng/mL, respectively. The meloxicam milk concentration was below the limit of quantification (1 ng/mL) in 15 of 22 animals at 96 hours and in 22 of 22 animals at 120 hours. The milk meloxicam levels in all animals were below the maximum residue limit (Canada: 35 ng/mL; Europe: 15 ng/mL) at the 72-hour sampling.

6.
Br J Cancer ; 112(5): 809-18, 2015 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-25647014

RESUMO

BACKGROUND: Follow-up care in breast cancer is still an issue of debate. Diagnostic methods are more sensitive, and more effective therapeutic options are now available. The risk of recurrence is not only influenced by tumour stage but also by the different molecular subtypes. This study was performed to evaluate the use of whole-body imaging combined with tumour marker monitoring for the early detection of asymptomatic metastatic breast cancer (MBC). METHODS: This analysis was performed as part of a follow-up study evaluating 813 patients with a median follow-up of 63 months. After primary therapy, all patients underwent tumour marker monitoring for CEA, CA 15-3 and CA 125 at 6-week intervals within an intensified diagnostic aftercare algorithm. A reproducible previously defined increase was considered as a strong indicator of MBC. From 2007 to 2010, 44 patients with tumour marker increase underwent whole-body magnetic resonance imaging and/or an FDG-PET/CT scan. Histological clarification and/or imaging follow-up were done. RESULTS: Metastases were detected in 65.9% (29/44) of patients, 13.6% (6/44) had secondary malignancies besides breast cancer and 20.5% (9/44) had no detectable malignancy. Limited disease was found in 24.1% (7/29) of patients. Median progression-free survival of MBC was 9.2 months and median overall survival was 41.1 months. The 3- and 5-year survival rates were 64.2% and 40.0%, respectively. CONCLUSIONS: A reproducible tumour marker increase followed by whole-body imaging is highly effective for early detection. By consequence, patients might benefit from earlier detection and improved therapeutic options with a prolonged survival.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/diagnóstico , Detecção Precoce de Câncer/métodos , Neoplasias/diagnóstico , Imagem Corporal Total/métodos , Adulto , Idoso , Neoplasias da Mama/complicações , Neoplasias da Mama/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Metástase Neoplásica/diagnóstico , Neoplasias/complicações , Tomografia por Emissão de Pósitrons , Análise de Sobrevida , Tomografia Computadorizada por Raios X
7.
Oncogene ; 33(50): 5655-65, 2014 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-24469030

RESUMO

The discovery of constitutive nuclear factor-κB (NF-κB) activation in Hodgkin's lymphoma tumor cells almost two decades ago was one of the first reports that directly connected deregulated NF-κB signaling to human cancer. Subsequent studies demonstrated that enhanced NF-κB signaling is a common hallmark of many lymphoid malignancies, including Hodgkin lymphoma, mucosa-associated lymphoid tissue lymphoma, diffuse large B-cell lymphoma and multiple myeloma. By inducing an anti-apoptotic and pro-proliferative gene program, NF-κB is involved in lymphoma survival and growth. Identification of somatic mutations that led to activation of oncogenes and inactivation of tumor suppressor genes in the pathway revealed that specific pathogenic mechanisms are responsible for constitutive NF-κB activation in different lymphoma entities. Thus, the identification of distinct oncogenic events is reflecting the diverse cellular origins of the different lymphomas. Further, elucidation of the mechanisms that drive NF-κB in lymphoma is of high clinical relevance as it will allow the design of target-directed precision therapy. Indeed, a number of drugs that impair constitutive NF-κB activation in lymphoid malignancies are currently in preclinical or clinical development.


Assuntos
Linfoma de Células B/metabolismo , NF-kappa B/metabolismo , Doença de Hodgkin/genética , Doença de Hodgkin/metabolismo , Doença de Hodgkin/patologia , Humanos , Linfoma de Células B/genética , Linfoma de Células B/patologia , Linfoma de Zona Marginal Tipo Células B/genética , Linfoma de Zona Marginal Tipo Células B/metabolismo , Linfoma de Zona Marginal Tipo Células B/patologia , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Transporte Proteico , Transdução de Sinais
8.
J Mater Chem B ; 2(42): 7307-7315, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-32261955

RESUMO

Analysis of protein function in a cellular context ideally requires physiologically representative levels of that protein. Thus conventional nucleic acid-based transfection methods are far from ideal owing to the over expression that generally results. Likewise, fusions with protein transduction domains can be problematic whilst delivery via liposomes/nanoparticles typically results in endosomal localisation. Recently, polymer microspheres have been reported to be highly effective at delivering proteins into cells and thus provide a viable new alternative for protein delivery (protein transduction). Herein we describe the successful delivery of active ribonuclease A into HeLa cells via novel polymer core-silica shell microspheres. Specifically, poly(styrene-co-vinylbenzylisothiouronium chloride) core particles, generated by dispersion polymerisation, were coated with a poly(styrene-co-trimethoxysilylpropyl methacrylate) shell. The resultant core-shell morphology was characterised by transmission electron, scanning electron and confocal fluorescence microscopies, whilst size and surface charge was assessed by dynamic light scattering and zeta-potential measurements, respectively. Subsequently, ribonuclease A was coupled to the microspheres using simple carbodiimide chemistry. Gel electrophoresis confirmed and quantified the activity of the immobilised enzyme against purified HeLa RNA. Finally, the polymer-protein particles were evaluated as protein-transduction vectors in vitro to deliver active ribonuclease A to HeLa cells. Cellular uptake of the microspheres was successful and resulted in reduced levels of both intracellular RNA and cell viability.

9.
Br J Cancer ; 108(8): 1684-94, 2013 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-23579210

RESUMO

BACKGROUND: CYFRA 21-1 serves as biomarker in several epithelial malignancies. However, its role in pancreatic cancer (PC) has not yet been investigated. METHODS: Within a prospective single-centre study serial blood samples were collected from patients with confirmed advanced PC. Pre-treatment values and weekly measurements of CYFRA 21-1, carbohydrate antigen 19-9 (CA 19-9) and carcinoembryonic antigen (assessed by Elecsys 2010, Roche Diagnostics) during palliative first-line chemotherapy were obtained. Biomarker data were correlated with objective response (determined by RECIST) as well as time to progression (TTP) and overall survival (OS) using uni- and multivariate analyses. RESULTS: Seventy-eight patients were included, 45% of these received treatment in prospective clinical trials. Median TTP was 3.9 months, median OS 7.7 months. Pre-treatment CYFRA 21-1 levels were significantly associated with performance status (P=0.0399) and stage of disease (P=0.0001). Marker values before chemotherapy and at the 2-month staging of all three markers were considered significant predictors for objective treatment response. Pre-treatment CYFRA 21-1 levels, as well as CA 19-9 values, could be applied to define subgroups (categorised by tertiles) with a different OS outcome (CYFRA: 14.8 vs 7.1 vs 4.8 months, CA 19-9: 14.2 vs 7.1 vs 5.2 months; P<0.0001). CYFRA 21-1 and CA 19-9 (both as categorised and as continuous variables) showed a highly significant correlation with TTP and OS at nearly all-time points assessed in univariate analysis. In multivariate analysis, only CYFRA 21-1 and performance status were independent predictors for OS. CONCLUSIONS: CYFRA 21-1 may serve as a valuable tool for monitoring treatment response and assessing prognosis in advanced PC.


Assuntos
Antígenos de Neoplasias/sangue , Biomarcadores Tumorais/sangue , Queratina-19/sangue , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/tratamento farmacológico , Adulto , Idoso , Albuminas/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Axitinibe , Antígeno CA-19-9/sangue , Capecitabina , Antígeno Carcinoembrionário/sangue , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Intervalo Livre de Doença , Cloridrato de Erlotinib , Everolimo , Fluoruracila/administração & dosagem , Fluoruracila/análogos & derivados , Fluoruracila/uso terapêutico , Humanos , Imidazóis/administração & dosagem , Indazóis/administração & dosagem , Pessoa de Meia-Idade , Análise Multivariada , Oximas , Paclitaxel/uso terapêutico , Cuidados Paliativos , Piperazinas/administração & dosagem , Estudos Prospectivos , Quinazolinas/administração & dosagem , Sirolimo/administração & dosagem , Sirolimo/análogos & derivados , Sulfonamidas/administração & dosagem , Taxa de Sobrevida , Gencitabina
10.
Eur J Med Res ; 16(10): 445-50, 2011 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-22024423

RESUMO

OBJECTIVE: To evaluate the performance of total PSA (tPSA), the free/total PSA ratio (f/tPSA), complexed PSA (cPSA) and the complexed/total PSA ratio (c/tPSA) in prostate cancer detection. METHODS: Frozen sera of 442 patients have been analysed for tPSA, free PSA (fPSA) and cPSA. 131 patients had prostate cancer and 311 patients benign prostatic hyperplasia. RESULTS: Differences in the distribution of the biomarkers were seen as follows: tPSA, cPSA and c/tPSA were significantly higher in the PC group, and f/tPSA was significantly higher in the BPH group. In the tPSA-range of 0-4 ng/ml none of the biomarkers showed a significant difference in the distribution between both groups. In the tPSA-ranges of 0-10 ng/ml, 2-10 ng/ml, 4-10 ng/ml and <10 ng/ml, f/tPSA showed the highest specificity at high sensitivtities, followed by c/tPSA, cPSA, and tPSA, respectively. In tPSA-ranges greater than 10 ng/ml, cPSA offered the best discriminatory ability. CPSA compared to tPSA offered better specificity at high sensitivities in all tPSA-ranges. CONCLUSION: F/tPSA offers the best ability to distinguish between both groups in lower tPSA-ranges, followed by c/tPSA. CPSA compared to tPSA offers a better ability to discriminate between both groups in all PSA-ranges and could be used as an initial test for PC.


Assuntos
Antígeno Prostático Específico/sangue , Hiperplasia Prostática/sangue , Neoplasias da Próstata/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/patologia , Neoplasias da Próstata/patologia , Curva ROC
11.
Stat Med ; 28(8): 1218-37, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19222087

RESUMO

One difficulty in performing meta-analyses of observational cohort studies is that the availability of confounders may vary between cohorts, so that some cohorts provide fully adjusted analyses while others only provide partially adjusted analyses. Commonly, analyses of the association between an exposure and disease either are restricted to cohorts with full confounder information, or use all cohorts but do not fully adjust for confounding. We propose using a bivariate random-effects meta-analysis model to use information from all available cohorts while still adjusting for all the potential confounders. Our method uses both the fully adjusted and the partially adjusted estimated effects in the cohorts with full confounder information, together with an estimate of their within-cohort correlation. The method is applied to estimate the association between fibrinogen level and coronary heart disease incidence using data from 154,012 participants in 31 cohorts


Assuntos
Estudos de Coortes , Interpretação Estatística de Dados , Metanálise como Assunto , Modelos Estatísticos , Simulação por Computador , Doença das Coronárias/metabolismo , Feminino , Fibrinogênio/análise , Humanos , Masculino
12.
Gut ; 58(2): 241-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18852257

RESUMO

BACKGROUND AND AIMS: This prospective trial was designed to compare the performance characteristics of five different screening tests in parallel for the detection of advanced colonic neoplasia: CT colonography (CTC), colonoscopy (OC), flexible sigmoidoscopy (FS), faecal immunochemical stool testing (FIT) and faecal occult blood testing (FOBT). METHODS: Average risk adults provided stool specimens for FOBT and FIT, and underwent same-day low-dose 64-multidetector row CTC and OC using segmentally unblinded OC as the standard of reference. Sensitivities and specificities were calculated for each single test, and for combinations of FS and stool tests. CTC radiation exposure was measured, and patient comfort levels and preferences were assessed by questionnaire. RESULTS: 221 adenomas were detected in 307 subjects who completed CTC (mean radiation dose, 4.5 mSv) and OC; 269 patients provided stool samples for both FOBT and FIT. Sensitivities of OC, CTC, FS, FIT and FOBT for advanced colonic neoplasia were 100% (95% CI 88.4% to 100%), 96.7% (82.8% to 99.9%), 83.3% (95% CI 65.3% to 94.4%), 32% (95% CI 14.9% to 53.5) and 20% (95% CI 6.8% to 40.7%), respectively. Combination of FS with FOBT or FIT led to no relevant increase in sensitivity. 12 of 45 advanced adenomas were smaller than 10 mm. 46% of patients preferred CTC and 37% preferred OC (p<0.001). CONCLUSIONS: High-resolution and low-dose CTC is feasible for colorectal cancer screening and reaches sensitivities comparable with OC for polyps >5 mm. For patients who refuse full bowel preparation and OC or CTC, FS should be preferred over stool tests. However, in cases where stool tests are performed, FIT should be recommended rather than FOBT.


Assuntos
Adenoma/diagnóstico , Neoplasias Colorretais/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Colo/patologia , Pólipos do Colo/diagnóstico , Colonografia Tomográfica Computadorizada/métodos , Colonoscopia/métodos , Fezes/química , Feminino , Hemoglobinas/análise , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Sangue Oculto , Estudos Prospectivos , Reto/patologia , Tamanho da Amostra , Sensibilidade e Especificidade , Sigmoidoscopia/métodos , Gravação em Vídeo
13.
Plant Dis ; 91(11): 1514, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30780771

RESUMO

During the summer of 2005, an uncharacterized disease was observed on sweet corn 'Mirai 301BC' commercially grown in Sunflower County, Mississippi. Initial symptoms developing at the base of the ear on interior husk leaves were brown, water-soaked, irregular lesions. These gradually enlarged up to 10 cm in diameter. Market value was significantly affected when the corn ears had visible symptoms of this disease. Bacterial cell streaming was observed at a magnification of ×675 from the diseased husk. A bacterium was consistently isolated from lesions on nutrient broth yeast (NBY) agar. Colonies on NBY were yellowish white, slightly convex, shiny, and circular with entire margins. Isolates MS102 and MS103, which were chosen for further characterization, were gram negative, lacked arginine dihydrolase, did not produce fluorescent pigment on Pseudomonas F medium, accumulated poly-ß-hydroxybutyrate, and grew aerobically. The isolates were able to utilize l-arabinose, d-mannitol, N-acetylglucosamine, capric acid, malic acid, adipic acid, and phenylacetic acid, but not d-maltose. These characteristics are the same as those described previously for Burkholderia gladioli (3). Analysis of fatty acid methyl ester profiles (Sherlock version TSBA 4.10; Microbial Identification System, Newark, DE) characterized the isolates as B. gladioli (similarity indices: 0.23 to 0.38) and revealed that they have C16:0 3OH, the most characteristic fatty acid for the genus Burkholderia. Confirmation was made by PCR amplification of the nearly complete16S rRNA gene (1,471 bp; GenBank Accession No. EU053154) using universal primers (forward: 5'-AGAGTTTGATCCTGGCTCAG and reverse: 5'-GGCTACCTTGTTACGACTTC). DNA sequence analysis demonstrated that the 16S rRNA gene of the bacterium shared highest identities (99.4 to 99.6%) with that of B. gladioli strains 321gr-6, 223gr-1, and S10 (4). A PCR product (approximately 300 bp) characteristic of B. gladioli also was obtained from both isolates using species-specific primers GLA-f and GLA-r (2). To confirm pathogenicity, cell suspensions (108 CFU/ml in phosphate buffer) of isolates MS102 and MS103 were injected into interior husk leaves of field-grown sweet corn with a 20-gauge needle and syringe (2 ml per ear). Control corn ear husks were injected with phosphate buffer. After 3 days, ear rot symptoms were observed on all plants inoculated with the isolates but not those injected with phosphate buffer. Cell suspension of isolates dropped on nonwounded husks also incited the same symptoms as those inoculated with the syringe. Koch's postulates were fulfilled with reisolation from the inoculated tissues. The identity of the reisolated pathogen was proved by sequencing the 16S rRNA gene. This disease was previously reported in Brazil (1). To our knowledge, this is the first report of B. gladioli causing a disease of corn in the United States. Although the impact of this disease was not observed from 2005 to 2006 because of dry weather and rotation to other crops in the affected field, there is a potential that the bacterium could become established in corn-producing areas as a member of the corn ear rot complex if environmental conditions are favorable. Reference: (1) I. M. G. Almeida et al. Arq. Inst. Biol. Sao Paulo 66:141, 1999. (2) N. Furuya et al. J. Gen. Plant Pathol. 68:220, 2002. (3) M. Gillis et al. Int. J. Syst. Bacteriol. 45:274, 1995. (4) R. Nandakumar et al. Phytopathology (Abstr.) 95(suppl.):S73, 2005.

14.
J Cell Biochem ; 93(6): 1107-14, 2004 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-15449321

RESUMO

MEPE, 56.6 kDa protein isolated from tumors associated with hypophosphatemic osteomalacia, increases renal phosphate excretion and is expressed in normal human bone cells. AC-100, a central 23-amino acid fragment of MEPE, contains motifs that are important in regulating cellular activities in the bone microenvironment. Thus, we assessed in vitro effects of AC-100 on multipotential normal human marrow stromal (hMS) cells that have the capacity to differentiate into mature osteoblasts. Proliferation was quantified by [H3]thymidine uptake and cell counting and differentiation by the levels of mRNA for the alpha2-chain of type I procollagen (COL1A2), alkaline phosphatase (AP), and osteocalcin (OC) measured using real time reverse transcriptase PCR (RT-PCR) and by the formation of mineralized nodules. AC-100 increased proliferation by 257 +/- 89% (P < 0.005), increased gene expression of COL1A2 by 339 +/- 85% (P < 0.005), AP by 1,437 +/- 40% (P < 0.001), and OC by 1,962 +/- 337% (P < 0.001). In addition, it increased mineralized nodule formation by 81 +/- 14% (P < 0.001) in a dose- and time-dependent fashion. In equimolar dosages, the parent compound, MEPE, had the full activity of the AC-100 fragment. AC-100 elicited a comparable response to both IGF-I and BMP-2 with respect to proliferation and differentiation of hMS cells. Using gene expression microarray analysis, we demonstrated that AC-100 increased (by approximately 3-fold) the mRNA for cyclooxgenase-2 (COX-2), an inducible enzyme required for prostaglandin synthesis. Moreover, NS-398, a specific inhibitor of COX-2 action completely blocked AC-100-induced increases in proliferation and differentiation. Thus, AC-100 has potent anabolic activity on osteoblast precursor cells in vitro and these effects require the induction of COX-2.


Assuntos
Medula Óssea/metabolismo , Proteínas da Matriz Extracelular/farmacologia , Glicoproteínas/farmacologia , Osteoblastos/metabolismo , Fosfoproteínas/farmacologia , Prostaglandina-Endoperóxido Sintases/metabolismo , Biomarcadores/metabolismo , Proteína Morfogenética Óssea 2 , Proteínas Morfogenéticas Ósseas/metabolismo , Diferenciação Celular , Proliferação de Células , Ciclo-Oxigenase 2 , Ativação Enzimática , Perfilação da Expressão Gênica , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Proteínas de Membrana , Mesoderma/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Células Estromais/metabolismo , Fator de Crescimento Transformador beta/metabolismo
15.
Vox Sang ; 86(3): 189-97, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15078254

RESUMO

BACKGROUND AND OBJECTIVES: Major studies are still lacking on the impact of differing intensities of long-term donor plasmapheresis, not only on total serum protein, albumin and immunoglobulin G (IgG), but also on humoral and cellular immunity, red cell and iron metabolism, and biochemical cardiovascular risk markers. MATERIALS AND METHODS: Three groups of donors, comprising 483 individuals undergoing differing intensities of long-term serial plasmapheresis, were entered into a cross-sectional study. A fourth control group consisted of 100 non-donors. In addition to measuring total protein, albumin and IgG levels, we determined parameters of humoral and cellular immunity, red cell and iron metabolism and recognized biochemical cardiovascular risk factors. RESULTS: The median annual net amount of plasma donated by the three donor groups was 37, 16 and 10 l, respectively (P < 0.0001). Donors had significantly lower total serum protein, albumin and IgG levels than non-donors (P < 0.0001), but the intensity of plasmapheresis had no influence on those parameters. Like non-donors, all plasma donors had normal humoral and cellular immunity. No increased rates of iron store depletion were observed in the three groups of plasma donors. Plasma donors were not at increased cardiovascular risk. CONCLUSIONS: Regular donor plasmapheresis of up to 45 l of plasma per year appears to be as safe as more moderate plasmapheresis programmes, with respect to the parameters analysed in this study. Individuals donating under these conditions did not develop impaired humoral and cellular immunity, iron store depletion, or increased cardiovascular risk with regard to established biochemical risk markers. Prospective studies are required to determine more exactly than in retrospective analyses the reasons why donors withdraw from plasmapheresis programmes.


Assuntos
Formação de Anticorpos , Doenças Cardiovasculares/epidemiologia , Eritrócitos/metabolismo , Imunidade Celular , Ferro/metabolismo , Plasmaferese/métodos , Contagem de Plaquetas , Adulto , Biomarcadores/sangue , Doadores de Sangue , Proteínas Sanguíneas/análise , Estudos de Coortes , Estudos Transversais , Feminino , Alemanha , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Plasmaferese/efeitos adversos , Fatores de Risco , Albumina Sérica/análise
16.
Z Kardiol ; 92(12): 1018-24, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14663612

RESUMO

Studies from the early 1990s found elevations of creatine kinase (CK) and its isoform CK-MB in 5-30% of patients after PCI, indicating minor myocardial damage. Less is known about the influence of modern improved PCI-techniques on the frequency of elevated cardiac markers and the correlation between different commonly used markers, especially cardiac troponins. From 1997 to 2001, 1486 patients undergoing PCI during the regular working hours were included in the prospective "Ludwigshafen Infarctlet Registry". Myocardial infarction in the past 48 hours was an exclusion criterion. Clinical and procedural data were documented. Follow-up data were obtained from discharge up to one year. PCI-related elevations of troponin T were found in 18%, of total-CK in 11%, of CK-MB in 33% and of myoglobin in 23% of cases. The correlation between the different markers was poor. Compared with troponin T, other markers showed low sensitivity (total-CK 58%, CK-MB 27%, myoglobin 22%) and, especially total-CK, low specificity. Stenting, side branch occlusion or major dissection, complex lesion morphology, gpIIbIIIa-antagonist application, proximal stenosis and unstable angina were independent predictors of an elevated troponin T in multivariate analysis. Due to this weak correlation between more specific and sensitive troponins and the other markers, troponins are preferred in monitoring after PCI. In addition to lesion characteristics, particularly stenting is associated with an increased rate of elevated troponin.


Assuntos
Angina Instável/terapia , Angioplastia Coronária com Balão , Creatina Quinase/sangue , Isoenzimas/sangue , Infarto do Miocárdio/diagnóstico , Mioglobina/sangue , Inibidores da Agregação Plaquetária/uso terapêutico , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Complicações Pós-Operatórias/diagnóstico , Stents , Troponina I/sangue , Troponina T/sangue , Idoso , Angina Instável/enzimologia , Biomarcadores/sangue , Creatina Quinase Forma MB , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/enzimologia , Complicações Pós-Operatórias/enzimologia , Valor Preditivo dos Testes , Prognóstico , Fatores de Risco , Estatística como Assunto
18.
Br J Cancer ; 86(8): 1217-22, 2002 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-11953875

RESUMO

In the present study, we investigated the association of the serum levels of the tumour markers carcinoembryonic antigen and cancer antigen 15-3 with disease free survival and death from disease in 1046 women with breast cancer without metastases at the time of primary diagnosis in relation to age and the established prognostic factors tumour size, lymph node status, histological grading and hormone receptor status. We found that elevated pre-operative serum marker values were correlated with early relapse (cancer antigen 15-3; P=0.0003) and death from disease (carcinoembryonic antigen, cancer antigen 15-3; P=0.0001 both) in univariate analyses. By comparing pre- and post-operative values we found a decline in values post-surgery. In those patients where marker levels of carcinoembryonic antigen decreased more than 33%, a significantly higher risk for relapse and death from disease (both P=0.0001) in univariate analyses was observed. In multivariate analysis this decrease of carcinoembryonic antigen proved to be an independent prognostic factor. The results for cancer antigen 15-3 were comparable to carcinoembryonic antigen in univariate analyses but showed no significance in multivariate analysis. In this study the post-operative decrease of the serum tumour marker carcinoembryonic antigen was a strong independent prognostic factor for disease free survival and death from disease in breast cancer patients.


Assuntos
Neoplasias da Mama/sangue , Neoplasias da Mama/diagnóstico , Antígeno Carcinoembrionário/sangue , Mucina-1/sangue , Intervalo Livre de Doença , Feminino , Humanos , Análise Multivariada , Prognóstico , Análise de Sobrevida
19.
Ann N Y Acad Sci ; 945: 93-102, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11708501

RESUMO

In the nucleus of eukaryotic cells, DNA is associated with several protein components and forms complexes known as nucleosomes. During cell death, particularly during apoptosis, endonucleases are activated that cleave the chromatin into multiple oligo- and mononucleosomes. Subsequently, these nucleosomes are packed into apoptotic bodies and are engulfed by macrophages or neighboring cells. In cases of high rates of cellular turnover and cell death, they also are released into the circulation and can be detected in serum or plasma. As enhanced cell death occurs under various pathologic conditions, elevated amounts of circulating nucleosomes are not specific for any benign or malignant disorder. However, the course of change in the nucleosomal levels in circulation of patients with malignant tumors during chemotherapy or radiotherapy is associated with the clinical outcome and can be useful for the therapeutic monitoring and the prediction of the therapeutic efficacy.


Assuntos
DNA/sangue , Neoplasias/sangue , Nucleossomos/metabolismo , Antineoplásicos/farmacologia , Morte Celular , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Nucleossomos/química , Relação Estrutura-Atividade
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