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1.
Appl Radiat Isot ; 202: 111044, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37797447

RESUMO

Terbium-152 is one of four terbium radioisotopes that together form a potential theranostic toolbox for the personalised treatment of tumours. As 152 Tb decay by positron emission it can be utilised for diagnostics by positron emission tomography. For use in radiopharmaceuticals and for activity measurements by an activity calibrator a high radionuclide purity of the material and an accurate and precise knowledge of the half-life is required. Mass-separation and radiochemical purification provide a production route of high purity 152Tb. In the current work, two mass-separated samples from the CERN-ISOLDE facility have been assayed at the National Physical Laboratory to investigate the radionuclide purity. These samples have been used to perform four measurements of the half-life by three independent techniques: high-purity germanium gamma-ray spectrometry, ionisation chamber measurements and liquid scintillation counting. From the four measurement campaigns a half-life of 17.8784(95) h has been determined. The reported half-life shows a significant difference to the currently evaluated half-life (ζ-score = 3.77), with a relative difference of 2.2 % and an order of magnitude improvement in the precision. This work also shows that under controlled conditions the combination of mass-separation and radiochemical separation can provide high-purity 152Tb.

2.
Phys Rev Lett ; 109(20): 202503, 2012 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-23215476

RESUMO

We report on direct time-of-flight based mass measurements of 16 light neutron-rich nuclei. These include the first determination of the masses of the Borromean drip-line nuclei (19)B, (22)C, and (29)F as well as that of (34)Na. In addition, the most precise determinations to date for (23)N and (31)Ne are reported. Coupled with recent interaction cross-section measurements, the present results support the occurrence of a two-neutron halo in (22)C, with a dominant ν2s(1/2)(2) configuration, and a single-neutron halo in (31)Ne with the valence neutron occupying predominantly the 2p(3/2) orbital. Despite a very low two-neutron separation energy the development of a halo in (19)B is hindered by the 1d(5/2)(2) character of the valence neutrons.

3.
J Physiol Pharmacol ; 48(3): 451-9, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9376628

RESUMO

The influence of free radicals on iodothyronine 5'-monodeiodinase activity, the enzyme responsible for the deiodination of thyroxine to most active thyroid hormone 3,3',5-triiodothyronine (T3), was examined in rabbit's liver. Incubation of the liver homogenate with the xanthine oxidase based free radical generating system (FRGS) caused a reduction in 5'-monodeiodinase activity to the 53.9% of initial value taken as 100%, and on increase (52.9% over the control value) in the level of lipid peroxidation by-product malondialdehyde. The inhibitory effect of FRGS on 5'-monodeiodinase activity was blocked by free radical scavengers: catalase (91.2%), thiourea (88.8%), superoxide dismutase (85%) and by some antioxidants; Trolox (the water soluble alpha-tocopherol analog, 81.4%) and glutathione (77.7%). These results suggest that oxygen radicals, hydrogen peroxide and hydroxyl radicals were involved in the inhibition of the 5'-monodeiodinase activity. The same scavengers significantly decreased the malondialdehyde formation. In the presence of the FRGS the amount of total SH groups (the cofactor of the deiodination reaction) was decreased in the liver homogenate to 51% of the initial value, and a positive relationship between the total SH groups levels and the 5'-monodeiodinase activity in the presence of free radical scavengers was observed. It suggests, that active oxygen radicals generated by FRGS may inactivate 5'-monodeiodinase, at least in part, by reduction of thiol cofactors.


Assuntos
Antioxidantes/farmacologia , Sequestradores de Radicais Livres/farmacologia , Iodeto Peroxidase/antagonistas & inibidores , Fígado/enzimologia , Compostos de Sulfidrila/metabolismo , Animais , Radicais Livres/farmacologia , Técnicas In Vitro , Iodeto Peroxidase/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Malondialdeído/metabolismo , Coelhos , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Xantina Oxidase
4.
Somatosens Mot Res ; 13(1): 49-58, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8725648

RESUMO

Electron-microscopic analyses of the mitochondrial organization within the neurite innervating the Pacinian corpuscle (PC) were performed to test the hypothesis that the sites of mechanotransduction are the filopodia projecting from the neurite's surface. Since high concentrations of mitochondria imply the need for metabolic energy, and since transduction mechanisms are heavily dependent on such energy, it was reasoned that the greatest concentration of mitochondria should occur near the filopodia if they are involved in mechanotransduction. The analysis that the mitochondria lie close to the terminal neurite's membrane, on average within 0.4 microns, and thus are ideally located for supplying energy for membrane mechanisms. Although they can be found in a ring-like array, as seen in cross-sections of the terminal neurite, their greatest concentration occurs where the filopodia project from the terminal neurite. A linear algebraic analysis of the data set confirmed a high probability of the joint occurrence of a filopodial base and an increased frequency (number) of mitochondria. Thus the results provide further circumstantial support for the hypothesis that transduction within the PC mechanoreceptors takes place at or near the filopodia.


Assuntos
Mitocôndrias/ultraestrutura , Neuritos/ultraestrutura , Corpúsculos de Pacini/ultraestrutura , Animais , Gatos , Gráficos por Computador , Processamento de Imagem Assistida por Computador , Mesentério/inervação , Microscopia Eletrônica , Condução Nervosa/fisiologia , Membranas Sinápticas/ultraestrutura
5.
Pneumonol Alergol Pol ; 64(11-12): 805-8, 1996.
Artigo em Polonês | MEDLINE | ID: mdl-9162327

RESUMO

We report a patient with recognised squamous cell carcinoma of the lung, who refused of surgical treatment, and who was observed for next 8 years. In the last year of the disease the laser coagulation and palliative radiotherapy were used for recanalization the right bronchus. The patient died 8 years and 6 months after diagnosis was made.


Assuntos
Carcinoma de Células Escamosas/terapia , Neoplasias Pulmonares/terapia , Cuidados Paliativos , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/fisiopatologia , Progressão da Doença , Evolução Fatal , Humanos , Fotocoagulação a Laser , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Radioterapia Adjuvante , Fumar/efeitos adversos
6.
Pneumonol Alergol Pol ; 63(1-2): 51-7, 1995.
Artigo em Polonês | MEDLINE | ID: mdl-7633370

RESUMO

The aim of the study was to assess the use of a new Nd:YAG laser--mediLas fibertom--in correcting malignant and benign stenoses of the airways. Eighteen patients were included in the study. In 9 these were caused by malignant tumors, in 3 by nonmalignant tumors, in 6 by post-inflammatory stenoses of the airways. Altogether 99 laser sessions were carried out. In patients with malignant diseases complete recanalization was achieved in 6 patients, in 2 partial. One patients did not benefit form the laser procedure. In patients with benign tumors complete recanalization was achieved in all of the patients. In 5 out of 6 patients the post inflammatory stenosis was corrected. Satisfactory results observed after the second, fourth and one year after the initial laser procedure encourage to use this from of therapy in cases of malignant and nonmalignant narrowing of the airways.


Assuntos
Obstrução das Vias Respiratórias/cirurgia , Terapia a Laser/instrumentação , Adolescente , Adulto , Idoso , Obstrução das Vias Respiratórias/etiologia , Broncoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Respiratórias/complicações , Doenças Respiratórias/diagnóstico , Doenças Respiratórias/cirurgia
7.
Biol Trace Elem Res ; 47(1-3): 69-74, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7779577

RESUMO

The protective effect of vitamin E and reduced glutathione (GSH) against lipid peroxidation in boar semen plasma was studied. The lipid peroxidation, measured by the test for thiobarbituric acid reactive substances (TBARS), doubled in the presence of the lipid peroxidation Fe(2+)-sodium ascorbate-inducing system. The ascorbate-induced TBARS were inhibited by about 62% through the water-soluble vitamin E analog (TROLOX) and about 57% by GSH. In the in vivo experiments, 7 wk of oral DL-alpha-tocopherol acetate (1000 IU/d/animal) administration caused a significant fall in the level of the semen plasma TBARS, from 2.2 +/- 0.09 to 1.2 +/- 0.13 nmol MDA/mL. The semen plasma superoxide dismutase (SOD) and GSSG tended to increase with the time of vitamin E administration, but the increment did not reach a significant level by the seventh week. The vitamin E supplementation significantly increased the number of spermatozoa per 1 cm3 of ejaculate. The protective role of vitamin E and GSH with respect to boar semen against fatty acid peroxidation and a positive influence of vitamin E supplementation on semen quality have been evidenced.


Assuntos
Antioxidantes/farmacologia , Glutationa/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Sêmen/fisiologia , Contagem de Espermatozoides/efeitos dos fármacos , Vitamina E/farmacologia , Administração Oral , Animais , Ácido Ascórbico/farmacologia , Cromanos/farmacologia , Alimentos Fortificados , Cinética , Masculino , Suínos , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Fatores de Tempo , Vitamina E/administração & dosagem
8.
IEEE Trans Biomed Eng ; 41(7): 698-703, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7927391

RESUMO

A hybrid digital/analog device capable of making high-resolution linear and area measurements from a standard monochromatic video image is described. The device is capable of dynamic as well as static data acquisition when used in conjunction with standard NTSC video recording equipment. Digital output allows for computer interfacing. Linear dimensions are obtained by electronically superimposing two horizontal and two vertical scaling lines on a video monitor. Each linear dimension has an eight-bit resolution and is displayed on the front panel with seven segment LED's. Eight-bit, digital-to-analog converters are also used to provide analog outputs. A measurement of the temporal deformation pattern of the accessory capsule surrounding a mechanoreceptor (Pacinian corpuscles) in response to vibratory displacements is demonstrated. Area measurements are obtained via a window comparator, a 6-MHz clock, and a 16-bit digital-to-analog converter. Data is only valid within the zone set by the scaling lines, allowing data regions to be isolated from noise, etc. The 16-bit digital signal measuring the area of interest is then converted for analog output. The measurement of the consensual pupillary reflex in response to full-field illumination (Ganzfeld) is given as an example.


Assuntos
Processamento de Imagem Assistida por Computador/instrumentação , Microscopia de Vídeo/instrumentação , Gravação em Vídeo/instrumentação , Animais , Calibragem , Desenho de Equipamento , Humanos , Processamento de Imagem Assistida por Computador/economia , Microscopia de Vídeo/métodos , Corpúsculos de Pacini/citologia , Corpúsculos de Pacini/fisiologia , Reflexo Pupilar , Gravação em Vídeo/métodos
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