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1.
Meat Sci ; 188: 108795, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35306298

RESUMO

Grass silage is barely used in intensive beef production, but it is unclear if its lower energy supply compared to maize-silage feeding really impairs growth performance. Diets with 100, 300, 500 or 750 g grass silage/kg dry matter replacing maize silage and concentrate were tested with or without dried corn-cob mix (CCM). Performance, carcass and meat quality were studied in 30 Limousin-sired bulls. Feeding grass silage, CCM, and concentrate in a ratio of 500:300:200 allowed to maintain a similar animal performance, carcass and meat quality compared to a conventional maize silage/concentrate diet. Increasing the dietary grass silage proportion to 750 g/kg decreased the shear force of the meat. The proportion of n-3 fatty acids in intramuscular fat increased with dietary grass silage proportion. Consequently, a strategic combination of grass silage with energy-rich forages may facilitate grassland-based feeding strategies in intensive beef production with favourable meat fatty acid profiles and a performance comparable to that with maize-silage based diets.


Assuntos
Silagem , Zea mays , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Masculino , Carne/análise , Poaceae , Silagem/análise
2.
J Rehabil Assist Technol Eng ; 5: 2055668318767364, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31191935

RESUMO

INTRODUCTION: Functional electrical stimulation cycling has various health benefits, but the mechanical power output and efficiency are very low compared to volitional muscle activation. Stimulation with variable frequency showed significantly higher power output values in experiments with a knee dynamometer. The aim of the present work was to compare stochastic modulation of inter-pulse interval to constant inter-pulse interval stimulation during functional electrical stimulation cycling. METHODS: Seventeen able-bodied subjects participated (n = 17). Quadriceps and hamstring muscle groups were stimulated with two activation patterns: P1-constant frequency, P2-stochastic inter-pulse interval. Power output was measured on functional electrical stimulation ergometer. RESULTS: Overall, mean power output with the stochastically modulated pattern P2 was lower than with P1 (12.57 ± 3.74 W vs. 11.44 ± 3.81 W, P1 vs. P2, p = 0.022), but no significant differences during the first 30 s and the last 30 s were observed. CONCLUSIONS: This study showed that stimulation strategies that use randomized modulation of inter-pulse intervals can negatively affect power output generation during functional electrical stimulation cycling. To minimise voluntary contractions, power measurement and assessment should be focused on the periods where only the quadriceps are stimulated.

3.
PLoS One ; 11(2): e0148628, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26890637

RESUMO

PURPOSE: (S)-4-(3-[18F]Fluoropropyl)-L-glutamic acid (18F-FSPG) is a novel radiopharmaceutical for Positron Emission Tomography (PET) imaging. It is a glutamate analogue that can be used to measure xC- transporter activity. This study was performed to assess the feasibility of 18F-FSPG for imaging orthotopic brain tumors in small animals and the translation of this approach in human subjects with intracranial malignancies. EXPERIMENTAL DESIGN: For the small animal study, GS9L glioblastoma cells were implanted into brains of Fischer rats and studied with 18F-FSPG, the 18F-labeled glucose derivative 18F-FDG and with the 18F-labeled amino acid derivative 18F-FET. For the human study, five subjects with either primary or metastatic brain cancer were recruited (mean age 50.4 years). After injection of 300 MBq of 18F-FSPG, 3 whole-body PET/Computed Tomography (CT) scans were obtained and safety parameters were measured. The three subjects with brain metastases also had an 18F-FDG PET/CT scan. Quantitative and qualitative comparison of the scans was performed to assess kinetics, biodistribution, and relative efficacy of the tracers. RESULTS: In the small animals, the orthotopic brain tumors were visualized well with 18F-FSPG. The high tumor uptake of 18F-FSPG in the GS9L model and the absence of background signal led to good tumor visualization with high contrast (tumor/brain ratio: 32.7). 18F-FDG and 18F-FET showed T/B ratios of 1.7 and 2.8, respectively. In the human pilot study, 18F-FSPG was well tolerated and there was similar distribution in all patients. All malignant lesions were positive with 18F-FSPG except for one low-grade primary brain tumor. In the 18F-FSPG-PET-positive tumors a similar T/B ratio was observed as in the animal model. CONCLUSIONS: 18F-FSPG is a novel PET radiopharmaceutical that demonstrates good uptake in both small animal and human studies of intracranial malignancies. Future studies on larger numbers of subjects and a wider array of brain tumors are planned. TRIAL REGISTRATION: ClinicalTrials.gov NCT01186601.


Assuntos
Neoplasias Encefálicas/diagnóstico , Ácido Glutâmico/análogos & derivados , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X , Tirosina/análogos & derivados , Adulto , Idoso , Animais , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Estudos de Casos e Controles , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Fluordesoxiglucose F18 , Glioblastoma/diagnóstico , Ácido Glutâmico/química , Xenoenxertos , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons/métodos , Ratos , Tomografia Computadorizada por Raios X/métodos , Tirosina/química
4.
J Nucl Med ; 54(6): 861-6, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23568366

RESUMO

UNLABELLED: The glutamic acid derivative (S)-4-(3-(18)F-Fluoropropyl)-l-glutamic acid ((18)F-FSPG, alias BAY 94-9392), a new PET tracer for the detection of malignant diseases, displayed promising results in non-small cell lung cancer patients. The aim of this study was to provide dosimetry estimates for (18)F-FSPG based on human whole-body PET/CT measurements. METHODS: (18)F-FSPG was prepared by a fully automated 2-step procedure and purified by a solid-phase extraction method. PET/CT scans were obtained for 5 healthy volunteers (mean age, 59 y; age range, 51-64 y; 2 men, 3 women). Human subjects were imaged for up to 240 min using a PET/CT scanner after intravenous injection of 299 ± 22.5 MBq of (18)F-FSPG. Image quantification, time-activity data modeling, estimation of normalized number of disintegrations, and production of dosimetry estimates were performed using the RADAR (RAdiation Dose Assessment Resource) method for internal dosimetry and in general concordance with the methodology and principles as presented in the MIRD 16 document. RESULTS: Because of the renal excretion of the tracer, the absorbed dose was highest in the urinary bladder wall and kidneys, followed by the pancreas and uterus. The individual organ doses (mSv/MBq) were 0.40 ± 0.058 for the urinary bladder wall, 0.11 ± 0.011 for the kidneys, 0.077 ± 0.020 for the pancreas, and 0.030 ± 0.0034 for the uterus. The calculated effective dose was 0.032 ± 0.0034 mSv/MBq. Absorbed dose to the bladder and the effective dose can be reduced significantly by frequent bladder-voiding intervals. For a 0.75-h voiding interval, the bladder dose was reduced to 0.10 ± 0.012 mSv/MBq, and the effective dose was reduced to 0.015 ± 0.0010 mSv/MBq. CONCLUSION: On the basis of the distribution and biokinetic data, the determined radiation dose for (18)F-FSPG was calculated to be 9.5 ± 1.0 mSv at a patient dose of 300 MBq, which is of similar magnitude to that of (18)F-FDG (5.7 mSv). The effective dose can be reduced to 4.5 ± 0.30 mSv (at 300 MBq), with a bladder-voiding interval of 0.75 h.


Assuntos
Glutamatos , Imagem Multimodal/métodos , Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Feminino , Glutamatos/efeitos adversos , Humanos , Marcação por Isótopo , Masculino , Pessoa de Meia-Idade , Radiometria , Segurança
5.
Dig Dis ; 21(4): 292-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14752218

RESUMO

Gastrointestinal cancers are usually diagnosed at advanced stages, making a curative treatment difficult. Biomarkers can help to overcome this problem by allowing earlier diagnosis, and thus better therapy. Proteomics tools are novel technologies to identify such biomarkers. This review summarizes advances in biomarker detection using two-dimensional gel electrophoresis (2D-PAGE), chromatography and mass spectrometry technologies. 2D-PAGE combined with mass spectrometry has led to the identification of several differentially expressed proteins in cancer tissue. However, for serum analysis, 2D-PAGE has severe limitations. For serum-based cancer diagnosis, surface-enhanced laser desorption-ionization time-of-flight (SELDI-TOF) mass spectrometry is a promising new technology. The potential of proteins identified with this technology as novel cancer biomarkers still needs to be confirmed in clinical trials.


Assuntos
Biomarcadores Tumorais , Neoplasias Gastrointestinais/diagnóstico , Proteínas de Neoplasias/análise , Proteômica , Eletroforese em Gel Bidimensional , Neoplasias Gastrointestinais/genética , Humanos , Espectrometria de Massas/métodos , Análise Serial de Proteínas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
6.
Am J Kidney Dis ; 40(2): 236-42, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12148095

RESUMO

BACKGROUND: Spiral computed tomographic angiography (CTA) is a noninvasive method to diagnose renal artery stenosis (RAS). In digital subtraction angiography (DSA), contrast media (CM) is injected directly into the renal artery; in CTA, a greater amount of CM is injected intravenously, potentially leading to an increased incidence of CM nephropathy. METHODS: We investigated 80 patients with suspected RAS randomized to either CTA or DSA prospectively. The following parameters were determined: serum creatinine level and single-shot inulin clearance for evaluation of renal function and urine alpha1-microglobulin and beta-N-acetyl-glucoseaminidase (beta-NAG) as markers for tubular toxicity. Data from 16 patients undergoing angioplasty in the same session were excluded. RESULTS: In the CTA and DSA groups, 163 +/- 13 and 104 +/- 56 mL of CM (mean +/- SD; P < 0.0001) were administered, respectively. Mean serum creatinine levels increased from 1.78 +/- 1.61 to 1.92 +/-1.73 mg/dL (157 +/- 142 to 170 +/- 153 micromol/L; P = 0.00001) in the CTA group and from 1.52 +/- 1.23 to 1.60 +/- 1.28 mg/dL (134 +/- 109 to 141 +/- 113 micromol/L; P = 0.01) in the DSA group. Mean inulin clearance decreased from 63 +/- 28 to 58 +/- 23 mL/min (P = 0.01) and 65 +/- 26 to 62 +/- 26 mL/min (P < 0.01), median beta-NAG levels increased from 4.6 to 6.0 U/g creatinine (P = not significant) and 2.5 to 8.0 U/g creatinine (P < 0.001), and median alpha1-microglobulin levels increased from 13 to 17 microg/g creatinine (P < 0.025) and 11 to 21 microg/g creatinine (P = not significant) in the CTA and DSA groups, respectively. CM nephropathy occurred in 3 of 33 patients in the CTA group and 2 of 31 patients in the DSA group. The increase in creatinine level was reversible in all patients within 7 days. CONCLUSION: On this study, CTA performed for the detection of RAS is not associated with an increased risk for CM nephropathy compared with intraarterial DSA despite a greater dose of CM.


Assuntos
Angiografia Digital/métodos , Meios de Contraste/efeitos adversos , Obstrução da Artéria Renal/diagnóstico por imagem , Artéria Renal , Insuficiência Renal/induzido quimicamente , Tomografia Computadorizada por Raios X/métodos , Nefropatias Diabéticas/induzido quimicamente , Nefropatias Diabéticas/epidemiologia , Feminino , Humanos , Incidência , Injeções Intra-Arteriais , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Obstrução da Artéria Renal/complicações , Insuficiência Renal/epidemiologia
7.
Eur Radiol ; 12(4): 804-9, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11960230

RESUMO

The aim of this study was to compare renal function between patients with renal angiography and patients with renal angiography and angioplasty (AP) for renal artery stenosis (RAS). Forty-seven patients with suspected RAS were prospectively investigated by digital subtraction angiography (DSA) using non-ionic low osmolar contrast media (CM). In 22 patients RAS was detected and in 16 cases an angioplasty was performed in the same session. The following parameters were determined 1 day prior to and after the DSA, respectively: serum creatinine (S-Crea, micromol/l) and single-shot inulin clearance (In-Cl, ml/min) for the evaluation of renal function; and urine alpha 1-microglobuline (AMG, microg/g Crea) and beta-N-acetyl-glucoseaminidase (beta-NAG, U/g Crea) as markers of tubular toxicity. Serum creatinine was measured additionally 2 days after CM had been injected. In both groups with and without AP 174+/-65 and 104+/-56 ml of CM ( p<0.0005) were used, respectively. There were no differences with regard to renal function or risk factors for CM nephrotoxicity between both groups. In the group with AP S-Crea and In-Cl (each: mean+/-SD) did not change significantly (before DSA: 171+/-158 and 61+/-24, after DSA: 189+/-177 and 61+/-25, respectively), beta-NAG (median) rose from 4 to 14 ( p<0.05) and AMG from 8 to 55 (n.s., because of high SD). In the group without AP S-Crea increased from 134+/-109 to 141+/-113 ( p<0.01), In-Cl dropped from 65+/-26 to 62+/-26 ( p<0,01), beta NAG (median) rose from 4 to 8 ( p=0.01), and AMG from 7 to 10 (n.s.). A rise in baseline S-Crea by more than 25% or 44 micromol/l occurred in 4 and 2 patients in the group with and without AP, respectively. Creatinine increase was reversible in all cases within 7 days. In this study using sensitive methods to detect changes of renal function and tubular toxicity no additional renal function impairment in DSA with angioplasty for RAS compared with DSA alone could be demonstrated. Our data suggest that AP performed for RAS has a beneficial effect on renal function.


Assuntos
Angiografia Digital , Angioplastia com Balão , Obstrução da Artéria Renal/diagnóstico por imagem , Obstrução da Artéria Renal/terapia , Estudos de Casos e Controles , Meios de Contraste , Creatinina/sangue , Feminino , Humanos , Inulina , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Obstrução da Artéria Renal/fisiopatologia , Fatores de Tempo , Ácidos Tri-Iodobenzoicos
8.
Toxicol Lett ; 128(1-3): 243-7, 2002 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-11869834

RESUMO

Male Long-Evans rats were exposed to 0 (controls) or 500 ppm trichloroethylene (TRI) for 6 months, 6 h daily, and 5 days a week. The TRI metabolites trichloroethanol (TCE) in blood and trichloroacetic acid (TCA) in urine were measured. Specific parameters related to the renal damage were determined in urine [biomarker for glomerular damage: high molecular weight proteins (HMW), albumin (ALB); for proximal tubular damage: N-acetyl-beta-D-glucosaminidase (NAG), low-molecular-weight-proteins (LMW)]. Significantly increased concentrations of NAG and LMW in urine of exposed rats were detected. No DNA-strand breaks in kidney cells could be detected using the comet assay, and histological examinations were performed. Histological alterations were observed in glomeruli and tubuli of exposed rats. The release of biomarkers for nephrotoxicity suggested alterations preferably in the proximal tubules of the exposed rats.


Assuntos
Etilenocloroidrina/análogos & derivados , Nefropatias/induzido quimicamente , Tricloroetileno/toxicidade , Acetilglucosaminidase/urina , Albuminúria , Animais , Ensaio Cometa , Fragmentação do DNA/efeitos dos fármacos , Etilenocloroidrina/sangue , Histocitoquímica , Exposição por Inalação , Nefropatias/patologia , Masculino , Ratos , Ratos Long-Evans , Ácido Tricloroacético/urina
9.
Fresenius J Anal Chem ; 366(8): 873-80, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11227425

RESUMO

The suitability of laser ablation ICP-MS for minor and trace analysis of archaeological iron finds, produced by a direct reduction process in a 'bloomery' furnace, is reported. The analysis of elemental impurities in the iron can provide useful archaeometallurgical information on the production process and the provenance of the iron. Since, even after refinement, the iron resulting from this process may contain many inclusions (slag, charcoal, holes, etc.), a method should be used with sufficient spatial resolution to preclude the inclusions from the analysis. The ablation parameters are selected such that ablation craters of approx. 100 microm in diameter are obtained. The method is validated with low alloy steel and cast iron standard reference materials and by a comparative analysis with electron probe microanalysis (EPMA). The precision is limited mainly by the homogeneity of the iron, rather than by instrumental reproducibility. The advantages and drawbacks of the method are briefly compared with EPMA. Preliminary results from the analysis of archaeological iron samples from excavations at Develier-Courtetelle (Canton Jura, CH), Neftenbach (Canton Zurich, CH), Wartau (Canton St Gallen, CH) and Mont Chemin (Canton Valais, CH) are given.

15.
Differentiation ; 14(1-2): 35-50, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-383562

RESUMO

The intermediate-sized filaments present in epidermal keratinocytes derived from mouse skin and in an established cell line (HEL) derived from spontaneous transformation of murine keratinocytes grown in vitro, have been examined by immunofluorescence microscopy, using antibodies directed against subunit proteins of different classes of intermediate-sized filaments, as well as by electron microscopy and gel electrophoresis of cytoskeletal preparations highly enriched in intermediate-sized filaments. The keratinocytes derived from neonatal skin, which are capable of only limited replication in vitro, show only a single type of intermediate-sized filaments, i.e., the tonofibril-like arrays of filaments containing prekeratin. HEL cells, which proliferate indefinitely in vitro, retain the tonofilament-like structures typical of differentiated epidermal cells but in addition display intermediate-sized filaments of the vimentin type, i.e., the filament system typically found in mesenchymal and mesenchyme-derived cells. We discuss the possibility that (i) the advent of vimentin-type filaments in epidermal cells in culture is related either to the transformed state or the in vitro growth conditions as such and (ii) other differentiated epithelial cells proliferating in vitro may have more than one system of intermediate-sized filaments.


Assuntos
Citoesqueleto/ultraestrutura , Epiderme/ultraestrutura , Pele/ultraestrutura , Animais , Diferenciação Celular , Divisão Celular , Linhagem Celular , Transformação Celular Neoplásica/ultraestrutura , Células Cultivadas , Imunofluorescência , Queratinas/metabolismo , Camundongos , Peptídeos/metabolismo , Precursores de Proteínas/metabolismo
16.
J Cell Biol ; 69(1): 173-95, 1976 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1254641

RESUMO

The ultrastructure of the apical zone of lactating rat mammary epithelial cells was studied with emphasis on vesicle coat structures. Typical 40-60 nm ID "coated vesicles" were abundant, frequently associated with the internal filamentous plasma membrane coat or in direct continuity with secretory vesicles (SV) or plasma membrane proper. Bristle coats partially or totally covered membranes of secretory vesicles identified by their casein micelle content. This coat survived SV isolation. Exocytotic fusion of SV membranes and release of the casein micelles was observed. Frequently, regularly arranged bristle coat structures were identified in those regions of the plasma membrane that were involved in exocytotic processes. Both coated and uncoated surfaces of the casein-containing vesicles, as well as typical "coated vesicles", were frequently associated with microtubules and/or microfilaments. We suggest that coat materials of vesicles are related or identical to components of the internal coat of the surface membrane and that new plasma membrane and associated internal coat is produced concomitantly by fusion and integration of bristle coat moieties. Postexocytotic association of secreted casein micelles with the cell surface, mediated by finely filamentous extensions, provided a marker for the integrated vesicle membrane. An arrangement of SV with the inner surface of the plasma membrane is described which is characterized by regularly spaced, heabily stained membrane to membrane cross-bridges (pre-exocytotic attachment plaques). Such membrane-interconnecting elements may represent a form of coat structure important to recognition and interaction of membrane surfaces.


Assuntos
Caseínas/metabolismo , Glândulas Mamárias Animais/ultraestrutura , Animais , Membrana Celular/ultraestrutura , Células Epiteliais , Epitélio/ultraestrutura , Feminino , Lactação , Glândulas Mamárias Animais/fisiologia , Micelas , Microtúbulos/ultraestrutura , Organoides/ultraestrutura , Gravidez , Ratos
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