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1.
Phys Rev Lett ; 129(11): 111101, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36154418

RESUMO

The central region of the Milky Way is one of the foremost locations to look for dark matter (DM) signatures. We report the first results on a search for DM particle annihilation signals using new observations from an unprecedented γ-ray survey of the Galactic Center (GC) region, i.e., the Inner Galaxy Survey, at very high energies (≳100 GeV) performed with the H.E.S.S. array of five ground-based Cherenkov telescopes. No significant γ-ray excess is found in the search region of the 2014-2020 dataset and a profile likelihood ratio analysis is carried out to set exclusion limits on the annihilation cross section ⟨σv⟩. Assuming Einasto and Navarro-Frenk-White (NFW) DM density profiles at the GC, these constraints are the strongest obtained so far in the TeV DM mass range. For the Einasto profile, the constraints reach ⟨σv⟩ values of 3.7×10^{-26} cm^{3} s^{-1} for 1.5 TeV DM mass in the W^{+}W^{-} annihilation channel, and 1.2×10^{-26} cm^{3} s^{-1} for 0.7 TeV DM mass in the τ^{+}τ^{-} annihilation channel. With the H.E.S.S. Inner Galaxy Survey, ground-based γ-ray observations thus probe ⟨σv⟩ values expected from thermal-relic annihilating TeV DM particles.

2.
Cell Mol Biol (Noisy-le-grand) ; 56(2): 44-6, 2010 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-20525459

RESUMO

The aim of the present work is to propose a protocol for quantification of (18)F-FDG activities at organ level through whole body exams with Positron Emission Tomography. They were selected patients with normal uptake or a single tumor. In the period 2004-2005, 745 patients were studied. Among then, it was selected 97 adults for the normal uptake control group. The main studies were: intestine; colon, rectum, lung, lymphoma and melanoma, liver, esophagus, gonads and breasts. For "prospective screening", it were selected 20 patients with the identical physical characteristics of the control group. For internal dosimetry, the main organs should be elected according the kinetics of (18)F-FDG, either considering normal uptake or pathologies. Absorbed doses due to Computed Tomography and F-FDG uptake were estimated. Comparisons between internal and external exposures, for the same organ, point out higher doses due to external irradiation, except for bladder and kidneys. For individual dose estimation, parameters such the effective half-life should be known and this information may be achieved by an adaptation of the routine protocol.


Assuntos
Fluordesoxiglucose F18/análise , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons/métodos , Radiometria/métodos , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Adulto Jovem
3.
Water Sci Technol ; 59(4): 737-44, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19237768

RESUMO

Persistent organic pollutants (POPs) are very difficult to degrade when present in the environment and finally accumulate in the human body. Therefore, it is essential to develop efficient technologies for removal of POPs from polluted sediments. In this study, the authors attempted to evaluate the potential of hexachlorobenzene (HCB; a POP) removal by using ultrasonic irradiation and its combination with other advanced chemical oxidation processes (AOPs) and surfactant addition. The average removal ratios for ultrasonic irradiation alone and ultrasonic in combination with UV light irradiation were almost identical at 40%, and the efficiency could be improved to about 49% by combination with photocatalysis or surfactant addition. The dual-frequency ultrasonic irradiation showed the highest HCB removal ratio.


Assuntos
Hexaclorobenzeno/isolamento & purificação , Modelos Químicos , Ultrassom , Catálise , Concentração de Íons de Hidrogênio , Processos Fotoquímicos , Soluções , Tensoativos/química , Raios Ultravioleta
4.
Rev Esp Med Nucl ; 27(1): 8-12, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18208776

RESUMO

OBJECTIVE: To determine the frequency of the types of parathyroid gland hyperplasia and the sensitivity of sestamibi-(99m)Tc (MIBI) scintigraphy and ultrasonography (US) of patients with secondary hyperparathyroidism (SHPT) due to chronic renal failure. MATERIAL AND METHODS: We studied 43 patients with SHPT (26 females and 17 males with age range of 27-75 years). Blood tests were performed to determine intact parathyroid hormone (PTH), calcium and phosphorus concentration and parathyroid MIBI scintigraphy and US examinations were done, to evaluate each glandular function and structure. Nineteen of the 43 patients underwent total parathyroidectomy and 69 abnormal glands were removed at operation. The 69 abnormal and 4 normal glands from patients that underwent total thyroidectomy were studied by light microscopy. The results were compared and correlation was calculated to: weight, MIBI uptake and US results. RESULTS: All 43 patients had elevated serum PTH ranged from 400 to 4,075 pg/ml (1,868.0 +/- 975.9 and normal range 10-75 pg/ml). Serum calcium and phosphorus concentration were 10.13 +/- 2.02 mg/dl and 5.28 +/- 2.07 mg/dl respectively. Fifty eight of 69 glands from surgical resection were MIBI positive and 11 were negative, but their cellular composition and presentation were similar. Hyperplasic glands had increased number of all cell types considered (chief, oxyphil and clear) compared to the normal gland. Chief cell hyperplasia was the most frequent type (81 %) followed by oxyphil (9 %), clear (6 %) and adenomatous type (4 %). False negative results of 10 % to US and 4.6 % to scintigraphy were found. The correlation of gland weight and MIBI uptake were not significant (p = 0.09). The sensitivity of MIBI scintigraphy was 84 % and US was 72.5 %. CONCLUSIONS: The MIBI scintigraphy is a very sensitive tool for pre-operative localization of hyperplasic parathyroid gland and should be used as the first imaging method. The association of MIBI and US is recommended because increases the sensitivity for preoperative hyperplasic parathyroid glands identification.


Assuntos
Hiperparatireoidismo Secundário/etiologia , Glândulas Paratireoides/patologia , Compostos Radiofarmacêuticos , Tecnécio Tc 99m Sestamibi , Adenoma/sangue , Adenoma/diagnóstico por imagem , Adenoma/cirurgia , Adulto , Idoso , Cálcio/sangue , Feminino , Humanos , Hiperparatireoidismo Secundário/patologia , Hiperplasia , Hipocalcemia/complicações , Falência Renal Crônica/complicações , Masculino , Pessoa de Meia-Idade , Glândulas Paratireoides/diagnóstico por imagem , Glândulas Paratireoides/cirurgia , Hormônio Paratireóideo/sangue , Neoplasias das Paratireoides/sangue , Neoplasias das Paratireoides/diagnóstico por imagem , Neoplasias das Paratireoides/cirurgia , Paratireoidectomia , Fósforo/sangue , Cintilografia , Sensibilidade e Especificidade , Método Simples-Cego , Ultrassonografia
5.
Eur J Pain ; 22(2): 355-369, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28952182

RESUMO

BACKGROUND: Approximately 40% of patients with chronic low back pain have a neuropathic component. In this study, we assessed the effects of analgesics on tactile hypersensitivity and walking distance in the rat cauda equina compression (CEC) model of neuropathic low back pain. METHODS: The effects of analgesics on tactile hypersensitivity were examined using the von Frey test in CEC and partial sciatic nerve ligation (pSNL) models. Effects on walking distance were assessed using a treadmill test. Levels of α2δ1 subunit and ATF-3 mRNA in dorsal-root ganglion (DRG) neurons and those of α2δ1 subunit protein in the spinal cord were determined using quantitative RT-PCR and western blotting, respectively. Histological features were assessed using immunohistological methods. RESULTS: Histological changes indicating nerve damage (increase in ATF-3 mRNA, decrease in NF-200 and an increase in CD68 immunoreactivity) were observed in the CEC model. Duloxetine had analgesic effects in both models and improved walking distance in the CEC model. Pregabalin had analgesic effects in both models; however, the effect was weaker in the CEC model than in the pSNL model. α2δ1 subunit expression in DRG neurons and in the spinal cord was unchanged in the CEC model, but significantly increased in the pSNL model. Indomethacin had no analgesic effect in either model. Intrathecal yohimbine inhibited the effects of duloxetine with significant effects on depression. CONCLUSIONS: These findings suggest that the analgesic effects of duloxetine are mainly mediated by the spinal monoamine system, independent of the antidepressant effects of this agent. SIGNIFICANCE: The findings of this study suggest that duloxetine may be an effective treatment of broad neuropathic pain states, including neuropathic low back pain. The analgesic effects of duloxetine might be mediated by alterations of the descending pain modulatory pathways in the spinal cord, independent of the antidepressant effects.


Assuntos
Analgésicos/farmacologia , Monoaminas Biogênicas/metabolismo , Cloridrato de Duloxetina/farmacologia , Neuralgia/tratamento farmacológico , Medula Espinal/efeitos dos fármacos , Caminhada/fisiologia , Analgésicos/uso terapêutico , Animais , Cloridrato de Duloxetina/uso terapêutico , Masculino , Neuralgia/metabolismo , Neuralgia/fisiopatologia , Ratos , Ratos Sprague-Dawley , Medula Espinal/metabolismo , Compressão da Medula Espinal/metabolismo , Compressão da Medula Espinal/fisiopatologia
6.
Eur J Pain ; 20(1): 79-91, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25820250

RESUMO

BACKGROUND: Pain is a prominent feature of interstitial cystitis/painful bladder syndrome (IC/PBS), but the underlying mechanisms are not fully understood. There is a lack of well-characterized research tools, such as pain evaluation methods and experimental animal models, for investigating non-ulcerative cystitis. We developed a novel method for evaluating bladder pain in mice with cyclophosphamide (CYP)-induced cystitis. METHODS: Cystitis was produced by a single intraperitoneal injection of CYP (300 mg/kg) or repeated injections of CYP (150 mg/kg once daily for 4 days). Blunt stimulation with a cotton probe was applied to the abdominal region, and the thresholds for withdrawal responses were measured quantitatively using an anaesthesiometer. RESULTS: The single injection of CYP provoked acute cystitis with severe bladder inflammation in mice. In these mice, we could detect an increased sensitivity to blunt stimulation, which was abolished by intravesical lidocaine. The stimulation induced phosphorylation of extracellular signal-regulated kinases in bladder-projecting sensory neurons. Chronic treatment with CYP produced persistent pain responses to the blunt stimulus. Although there were few signs of bladder inflammation in these mice, the concentration of nerve growth factor (NGF) was elevated in bladder tissue, and NGF antiserum inhibited the hypersensitivity. CONCLUSIONS: The blunt probe method is useful for evaluating bladder pain signalling in mice, and revealed the involvement of an NGF-sensitive pain pathway in chronic cystitis pain. This assessment method may be useful for studying the pathophysiology of bladder pain and for developing therapeutic strategies for non-ulcerative IC/PBS in patients.


Assuntos
Cistite Intersticial/metabolismo , Cistite Intersticial/fisiopatologia , Fator de Crescimento Neural/metabolismo , Medição da Dor/métodos , Dor/diagnóstico , Transdução de Sinais/fisiologia , Animais , Cistite Intersticial/induzido quimicamente , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL
7.
Biochim Biophys Acta ; 1427(2): 175-82, 1999 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-10216234

RESUMO

The oxidative effects of sodium n-propylthiosulfate, one of the causative agents of onion-induced hemolytic anemia in dogs, were investigated in vitro using three types of canine erythrocytes, which are differentiated by the concentration of reduced glutathione and the composition of intracellular cations. After incubation with sodium n-propylthiosulfate, the methemoglobin concentration and Heinz body count in all three types of erythrocytes increased and a decrease in the erythrocyte reduced glutathione concentration was then observed. The erythrocytes containing high concentrations of potassium and reduced glutathione (approximately five times the normal values) were more susceptible to oxidative damage by sodium n-propylthiosulfate than were the normal canine erythrocytes. The susceptibility of the erythrocytes containing high potassium and normal reduced glutathione concentrations was intermediate between those of erythrocytes containing high concentrations of potassium and reduced glutathione and normal canine erythrocytes. In addition, the depletion of erythrocyte reduced glutathione by 1-chloro-2, 4-dinitrobenzene resulted in a marked decrease in the oxidative injury induced by sodium n-propylthiosulfate in erythrocytes containing high concentrations of potassium and reduced glutathione. The generation of superoxide in erythrocytes containing high concentrations of potassium and reduced glutathione was 4.1 times higher than that in normal canine erythrocytes when the cells were incubated with sodium n-propylthiosulfate. These observations indicate that erythrocyte reduced glutathione, which is known as an antioxidant, accelerates the oxidative damage produced by sodium n-propylthiosulfate.


Assuntos
Eritrócitos/efeitos dos fármacos , Glutationa/deficiência , Cebolas/toxicidade , Oxidantes/toxicidade , Tiossulfatos/toxicidade , Anemia Hemolítica/induzido quimicamente , Animais , Células Cultivadas , Dinitroclorobenzeno/farmacologia , Cães , Eritrócitos/metabolismo , Glutationa/sangue , Metemoglobina/análise , Cebolas/química , Estresse Oxidativo , Potássio/sangue , Tiossulfatos/análise
8.
Chemosphere ; 41(6): 857-64, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10864158

RESUMO

A new thermal process has been proposed for remediating soils contaminated by chlorinated organic compounds, e.g., PCDD/Fs and PCBs. This is to apply the "zone combustion process" which utilizes stable combustion of coke particles in the packed bed to soils with air flow across the bed. The usefulness and validity were obtained the results showing that more than 98.9% of PCDD/Fs in the soil was successfully removed in a laboratory-scale experiment. Some pretreatment of the soil sample, such as drying, pre-granulation and addition of limestone was found to make the removal efficiency better. Although, some fundamentals on the behavior of PCDD/Fs, e.g., decomposition/vaporization ratios and formation of other compounds cannot be certainly identified yet, the present results clearly show a way to remediate the contaminated soils and solid wastes.


Assuntos
Benzofuranos/química , Dibenzodioxinas Policloradas/análogos & derivados , Poluentes do Solo/isolamento & purificação , Gerenciamento de Resíduos/instrumentação , Gerenciamento de Resíduos/métodos , Benzofuranos/análise , Benzofuranos/isolamento & purificação , Dibenzofuranos Policlorados , Estudos de Avaliação como Assunto , Previsões , Dibenzodioxinas Policloradas/análise , Dibenzodioxinas Policloradas/química , Dibenzodioxinas Policloradas/isolamento & purificação , Poluentes do Solo/análise , Temperatura
9.
Chemosphere ; 54(1): 97-104, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14559262

RESUMO

The objectives of this work are to understand the details of the mechanism of dioxin formation in the part of a sintering bed termed the dry zone, and to obtain ideas on how to prevent their formation. Sinter mixtures of various composition types were heated in a packed bed reactor, and dioxins in the outlet gas and in the sinter mixture residue were measured. The dioxin formation potential of a simple sinter mixture composed of iron ore, coke and limestone was markedly lower than that of fly ash from a municipal solid waste incinerator (MSWI). In consideration of this result, a series of experiments were conducted using a sinter mixture impregnated with CuCl2. Experimental results showed that dioxin formation was temperature-dependent in the range of 300-550 degrees C, with the maximum observed at around 300 degrees C, which was quite similar to that of fly ash from the MSWI. The homologue distribution of PCDD/Fs in gas and solid reflected the possible difference in carbonaceous materials in coke and activated coke. Gaseous hydrogen chloride acted as a chlorinating reagent for dioxin formation.


Assuntos
Dioxinas/síntese química , Poluição Ambiental/prevenção & controle , Metalurgia , Compostos Clorados/química , Cobre/química , Japão , Temperatura
10.
Environ Sci Technol ; 37(11): 2431-5, 2003 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-12831028

RESUMO

Experimental study was conducted to clarify the formation behavior of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) from carbonaceous materials through a de novo synthesis route. Samples were prepared by changing mixing method and composite state of metallic chloride in graphite powder in order to simulate the texture of "unburned carbonaceous particles", i.e., soot, formed in thermal processes. Reagents of KCl, CaCl2. 2H2O, FeCl3 x 6H2O, and CuCl2 x 2H2O were used as chlorine sources and were added to graphite powder with different methods. The composite state of metallic chloride was varied by preliminary treatments: hand-mixing, mixed-grinding using a high-intensity ball mill, and preheating at different temperatures between 500 and 1100 degrees C. In the de novo experiment, reaction temperature and oxygen concentration of flowed gas were set at 300 degrees C and 2.5 mol %, respectively. During the experiment, formation rates of CO and CO2 and the formed amounts of organic chlorine and PCDD/Fs were measured. The results show a reasonable relation between the amount of formed organic chlorine and oxidation rate of carbon, and the order of the activity of metallic chlorines was obtained as KCl < CaCl2 < FeCl3 << CuCl2. Furthermore, it was found that the effect of the composite state of metallic chloride on the formation of PCDD/Fs significantly depends on the kind of metal. The results will give useful information to examine the formation mechanism of PCDD/Fs from unburned carbon particles in thermal processes.


Assuntos
Benzofuranos/análise , Cloretos/química , Dibenzodioxinas Policloradas/análogos & derivados , Dibenzodioxinas Policloradas/química , Poluentes do Solo/análise , Carbono/química , Dibenzofuranos Policlorados , Metais/química , Oxirredução , Dibenzodioxinas Policloradas/análise , Temperatura
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