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1.
Phys Rev Lett ; 131(20): 202501, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38039485

RESUMO

The changes in mean-squared charge radii of neutron-deficient gold nuclei have been determined using the in-source, resonance-ionization laser spectroscopy technique, at the ISOLDE facility (CERN). From these new data, nuclear deformations are inferred, revealing a competition between deformed and spherical configurations. The isotopes ^{180,181,182}Au are observed to possess well-deformed ground states and, when moving to lighter masses, a sudden transition to near-spherical shapes is seen in the extremely neutron-deficient nuclides, ^{176,177,179}Au. A case of shape coexistence and shape staggering is identified in ^{178}Au which has a ground and isomeric state with different deformations. These new data reveal a pattern in ground-state deformation unique to the gold isotopes, whereby, when moving from the heavy to light masses, a plateau of well-deformed isotopes exists around the neutron midshell, flanked by near-spherical shapes in the heavier and lighter isotopes-a trend hitherto unseen elsewhere in the nuclear chart. The experimental charge radii are compared to those from Hartree-Fock-Bogoliubov calculations using the D1M Gogny interaction and configuration mixing between states of different deformation. The calculations are constrained by the known spins, parities, and magnetic moments of the ground states in gold nuclei and show a good agreement with the experimental results.

2.
Phys Rev Lett ; 126(3): 032502, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33543945

RESUMO

The mean-square charge radii of ^{207,208}Hg (Z=80, N=127, 128) have been studied for the first time and those of ^{202,203,206}Hg (N=122, 123, 126) remeasured by the application of in-source resonance-ionization laser spectroscopy at ISOLDE (CERN). The characteristic kink in the charge radii at the N=126 neutron shell closure has been revealed, providing the first information on its behavior below the Z=82 proton shell closure. A theoretical analysis has been performed within relativistic Hartree-Bogoliubov and nonrelativistic Hartree-Fock-Bogoliubov approaches, considering both the new mercury results and existing lead data. Contrary to previous interpretations, it is demonstrated that both the kink at N=126 and the odd-even staggering (OES) in its vicinity can be described predominately at the mean-field level and that pairing does not need to play a crucial role in their origin. A new OES mechanism is suggested, related to the staggering in the occupation of the different neutron orbitals in odd- and even-A nuclei, facilitated by particle-vibration coupling for odd-A nuclei.

3.
Nat Commun ; 8: 14520, 2017 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-28224987

RESUMO

Resonant laser ionization and spectroscopy are widely used techniques at radioactive ion beam facilities to produce pure beams of exotic nuclei and measure the shape, size, spin and electromagnetic multipole moments of these nuclei. However, in such measurements it is difficult to combine a high efficiency with a high spectral resolution. Here we demonstrate the on-line application of atomic laser ionization spectroscopy in a supersonic gas jet, a technique suited for high-precision studies of the ground- and isomeric-state properties of nuclei located at the extremes of stability. The technique is characterized in a measurement on actinium isotopes around the N=126 neutron shell closure. A significant improvement in the spectral resolution by more than one order of magnitude is achieved in these experiments without loss in efficiency.

4.
J Vet Intern Med ; 30(4): 1074-82, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27461722

RESUMO

BACKGROUND: Serum cystatin C (sCysC) and urinary cystatin C (uCysC) are potential biomarkers for early detection of chronic kidney disease (CKD) in cats. An in-depth clinical validation is required. OBJECTIVES: To evaluate CysC as a marker for CKD in cats and to compare assay performance of the turbidimetric assay (PETIA) with the previously validated nephelometric assay (PENIA). ANIMALS: Ninety cats were included: 49 CKD and 41 healthy cats. METHODS: Serum CysC and uCysC concentrations were prospectively evaluated in cats with CKD and healthy cats. Based on plasma exo-iohexol clearance test (PexICT), sCysC was evaluated to distinguish normal, borderline, and low GFR. Sensitivity and specificity to detect PexICT < 1.7 mL/min/kg were calculated. Serum CysC results of PENIA and PETIA were correlated with GFR. Statistical analysis was performed using general linear modeling. RESULTS: Cats with CKD had significantly higher mean ± SD sCysC (1.4 ± 0.5 mg/L) (P < .001) and uCysC/urinary creatinine (uCr) (291 ± 411 mg/mol) (P < .001) compared to healthy cats (sCysC 1.0 ± 0.3 and uCysC/uCr 0.32 ± 0.97). UCysC was detected in 35/49 CKD cats. R(2) values between GFR and sCysC or sCr were 0.39 and 0.71, respectively (sCysC or sCr = µ + GFR + Îµ). Sensitivity and specificity were 22 and 100% for sCysC and 83 and 93% for sCr. Serum CysC could not distinguish healthy from CKD cats, nor normal from borderline or low GFR, in contrast with sCr. CONCLUSION: Serum CysC is not a reliable marker of reduced GFR in cats and uCysC could not be detected in all CKD cats.


Assuntos
Biomarcadores/sangue , Doenças do Gato/diagnóstico , Cistatina C/sangue , Insuficiência Renal Crônica/veterinária , Animais , Biomarcadores/urina , Estudos de Casos e Controles , Doenças do Gato/sangue , Doenças do Gato/urina , Gatos , Cistatina C/urina , Feminino , Masculino , Nefelometria e Turbidimetria/veterinária , Valor Preditivo dos Testes , Valores de Referência
5.
Vet J ; 206(1): 91-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26324637

RESUMO

Serum cystatin C (sCysC) is a possible marker for early detection of chronic kidney disease (CKD) in cats. In contrast with serum creatinine (sCr), feline sCysC is not affected by age, breed or sex. However, further biological and clinical validation is required. The objectives of this study were: (1) to investigate if food intake and circadian rhythm affect feline sCysC; (2) to determine the stability of sCysC under different storage conditions, and (3) to investigate if plasma concentrations of CysC (pCysC) differed from sCysC. A crossover study with 10 healthy laboratory cats fed the same commercial dry food was performed to study the influence of feeding and diurnal variation. Storage effects and comparison of pCysC with sCysC were determined using healthy cats (n = 3 and n = 10, respectively) and cats with CKD (n= 4 and n = 17, respectively). A significant daily sCysC variation was seen. Pre- and postprandial sCysC and sCr concentrations did not change significantly. Serum CysC significantly increased during storage at room temperature. After freezing, sCysC significantly decreased after 5 and 12 months at both -20 °C and -72 °C. Plasma CysC was significantly lower than sCysC. These findings suggest that it is not mandatory to fast cats before evaluation of sCysC and sCr. Samples were stable during routinely used storage conditions. Based on these findings, freezing for more than 5 months is not recommended, although additional studies are required to evaluate the clinical relevance of decreased sCysC after prolonged storage. Plasma and serum CysC cannot be compared directly.


Assuntos
Ração Animal/análise , Anticoagulantes/farmacologia , Coleta de Amostras Sanguíneas/veterinária , Cistatina C/sangue , Animais , Biomarcadores , Gatos , Estudos Cross-Over , Cistatina C/química , Feminino , Masculino
6.
Vet J ; 204(2): 168-73, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25900195

RESUMO

Chronic kidney disease (CKD) is common in cats, but the routine renal markers, serum creatinine (sCr) and urea, are not sensitive or specific enough to detect early CKD. Serum cystatin C (sCysC) has advantages over sCr, both in humans and dogs, and sCysC concentration is significantly higher in cats with CKD than in healthy cats. The objective of this study was to determine the effect of age, sex and breed on feline sCysC and to establish a reference interval for feline sCysC. In total, 130 healthy cats aged 1-16 years were included. sCysC was determined using a validated particle-enhanced nephelometric immunoassay. sCr, urea, urine specific gravity, urinary protein:creatinine ratio (UPC) and systolic blood pressure (SBP) were also measured. No significant differences in sCysC concentration were observed among young, middle-aged and geriatric cats, female intact, female neutered cats, male intact and male neutered cats, or among purebred and domestic short-or longhaired cats. The 95% reference interval for feline sCysC was determined to be 0.58-1.95 mg/L. sCr was significantly higher in geriatric cats than young cats. Serum urea in geriatric cats was significantly higher than in middle-aged and young cats (P = 0.004 and P <0.001, respectively). SBP in geriatric cats was significantly higher than in both middle-aged and young cats (P = 0.004 and P = 0.040, respectively). Male neutered and female neutered cats had significantly higher serum urea concentrations than female intact cats (P = 0.003 and P = 0.006, respectively). Male intact cats had a significantly higher UPC than female intact and female neutered cats (P = 0.02 for each comparison). There were no significant differences among sex groups for USG. It is of concern that sCysC in the majority of cats with CKD in previous studies falls within the reference interval calculated in this study. Further studies are warranted to evaluate the diagnostic value of sCysC as a renal marker in cats.


Assuntos
Envelhecimento/fisiologia , Gatos/sangue , Cistatina C/sangue , Animais , Gatos/genética , Cistatina C/metabolismo , Feminino , Masculino , Valores de Referência
7.
J Vet Intern Med ; 28(4): 1152-64, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24814357

RESUMO

The occurrence of chronic kidney disease is underestimated in both human and veterinary medicine. Glomerular filtration rate (GFR) is considered the gold standard for evaluating kidney function. However, GFR assessment is time-consuming and labor-intensive and therefore not routinely used in practice. The commonly used indirect GFR markers, serum creatinine (sCr) and urea, are not sufficiently sensitive or specific to detect early renal dysfunction. Serum cystatin C (sCysC), a proteinase inhibitor, has most of the properties required for an endogenous GFR marker. In human medicine, numerous studies have evaluated its potential use as a GFR marker in several populations. In veterinary medicine, this marker is gaining interest. The measurement is easy, which makes it an interesting parameter for clinical use. This review summarizes current knowledge about cystatin C (CysC) in humans, dogs, and cats, including its history, assays, relationship with GFR, and biological and clinical variations in both human and veterinary medicine.


Assuntos
Cistatina C/sangue , Insuficiência Renal Crônica/veterinária , Animais , Biomarcadores/sangue , Doenças do Gato/sangue , Doenças do Gato/diagnóstico , Gatos , Doenças do Cão/sangue , Doenças do Cão/diagnóstico , Cães , Taxa de Filtração Glomerular/veterinária , Humanos , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/diagnóstico
8.
Nat Commun ; 4: 1835, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23673620

RESUMO

The radioactive element astatine exists only in trace amounts in nature. Its properties can therefore only be explored by study of the minute quantities of artificially produced isotopes or by performing theoretical calculations. One of the most important properties influencing the chemical behaviour is the energy required to remove one electron from the valence shell, referred to as the ionization potential. Here we use laser spectroscopy to probe the optical spectrum of astatine near the ionization threshold. The observed series of Rydberg states enabled the first determination of the ionization potential of the astatine atom, 9.31751(8) eV. New ab initio calculations are performed to support the experimental result. The measured value serves as a benchmark for quantum chemistry calculations of the properties of astatine as well as for the theoretical prediction of the ionization potential of superheavy element 117, the heaviest homologue of astatine.

9.
Acta Clin Belg ; 52(4): 207-10, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9351292

RESUMO

A questionnaire about attitudes and knowledge in palliative care treatment was sent to 185 general practitioners who participated such a seminar some months before. The response rate was low (69/185). Pain is the most frequent symptom. All the responding doctors assume they can treat pain adequately. However, none of them can answer the knowledge questions correctly. They appreciate the palliative care organizations for the help in symptom control or for difficulties in psychological symptoms. A multifactorial etiology might explain the difficult control of asthenia. This survey agrees with other studies that knowledge in symptom control and palliative care should be improved.


Assuntos
Competência Clínica , Medicina de Família e Comunidade/educação , Cuidados Paliativos , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/uso terapêutico , Astenia/etiologia , Astenia/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Hospitais para Doentes Terminais , Humanos , Morfina/administração & dosagem , Morfina/uso terapêutico , Neoplasias/fisiopatologia , Neoplasias/psicologia , Doenças do Sistema Nervoso/complicações , Nociceptores/fisiologia , Dor/etiologia , Dor/fisiopatologia , Dor/prevenção & controle , Padrões de Prática Médica , Inquéritos e Questionários
10.
J Pain Symptom Manage ; 9(2): 75-81, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8021538

RESUMO

Cancer pain treatment is well established. The World Health Organization provides clinicians an "analgesic ladder" scheme to optimize cancer pain treatment. At the beginning of the pain treatment, oral analgesic administration is preferred. The analgesic dose must be individualized. Many published papers describe the spinal administration of opioids in combination with various other drugs such as bupivacaine in selected patients with cancer pain. Although complications have been reported to be few, some recent reports debate this idea. We first describe a population of 92 cancer patients, 13 of whom received intrathecal morphine. We then present our experience with a separate group of 33 cancer patients who were also managed using intrathecal morphine. Based on this experience, the generally accepted indications for the technique appeared to be justified. Concern about spinal infection is well considered, however. Three out of those patients developed meningitis, a complication rate that is far too high.


Assuntos
Analgesia/métodos , Morfina/administração & dosagem , Neoplasias/complicações , Dor Intratável/tratamento farmacológico , Assistência Terminal , Humanos , Injeções Espinhais , Fatores de Risco
11.
Clin J Pain ; 9(3): 220-3, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8219524

RESUMO

OBJECTIVE: To demonstrate difficulties encountered in alleviating neuropathic pain in a terminally ill cancer patient, with the very tentative diagnosis of postherpetic neuralgia. SETTING: A multidisciplinary pain department in a university hospital. PATIENTS: A patient with Hodgkin's lymphoma and leiomyosarcoma in the liver developed an unusual manifestation of neuropathic pain. INTERVENTION: Oral drug treatment with morphine associated with amitriptyline, valproic acid, mexilitine, flufenazine, and methylprednisolone failed to suppress pain attacks. Only the subcutaneous instillation of lidocaine (2 mg/kg/h) could partially suppress pain. A dorsal root entry zone lesion intervention could only temporary stop the pain attacks. Infiltration and nervous stimulation techniques were not helpful. OUTCOME MEASURES: In determining pain control, the visual analog scale rating scale and the number of attacks per hour were considered. RESULTS: Only the subcutaneous administration of lignocaine could partially suppress pain. Because of the patient's poor hepatic circulation, variable lidocaine plasma concentrations were responsible for intolerable side effects. CONCLUSIONS: Subcutaneous lignocaine administration remains a useful method in treating neuropathic cancer pain. The poor metabolic condition of the patient can lead to deleterious high plasma levels. A dorsal root entry zone lesion could only temporarily stop the pain.


Assuntos
Doença de Hodgkin/complicações , Leiomiossarcoma/complicações , Lidocaína/uso terapêutico , Neoplasias Hepáticas/complicações , Dor/tratamento farmacológico , Adulto , Analgesia Epidural , Bloqueio Nervoso Autônomo , Potenciais Evocados/fisiologia , Doença de Hodgkin/fisiopatologia , Humanos , Injeções Subcutâneas , Leiomiossarcoma/fisiopatologia , Lidocaína/administração & dosagem , Lidocaína/efeitos adversos , Circulação Hepática , Neoplasias Hepáticas/fisiopatologia , Masculino , Dor/etiologia , Gânglio Estrelado , Resultado do Tratamento
12.
J Dermatol Sci ; 4(3): 172-9, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1283698

RESUMO

The skin vascular responses (weal, flare, blood flow measurements) elicited by intradermal administration by pricking of histamine (HS) and substance P (SP) were evaluated 6 h after a single intake of anti-H1 agents displaying different activity profile on skin tests at currently recommended dosages (loratadine 10 mg, cetirizine 10 mg) as compared to placebo (P). The weal and flare response and the increases of blood flow occurring in the usual flare area after HS and SP were almost completely abolished by cetirizine. Inhibition of HS- and SP-induced weal and flare reactions was less marked after loratadine and blood flow in the expanding flare after HS and SP showed significant fluctuations over time. In view of the present results and of data obtained in previous experiments with intradermal injection of agonists, we hypothesize that mode of administration of agonists significantly influences the size of the residual weal after anti-H1 agents. We demonstrate that SP weals induced by pricking are largely inhibited by a potent H1 blockade which supports the view that this phenomenon, as well as the SP-flare, is due to SP-induced histamine liberation. We also, for the first time, report on fluctuations recorded at the edge of the developing flare with laser Doppler flowmetry early after prick testing with a weak H1 blockade. This opens up new avenues in dynamically testing H1-receptor occupancy in vivo and in situ in human skin.


Assuntos
Cetirizina/farmacologia , Loratadina/farmacologia , Pele/efeitos dos fármacos , Adulto , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Feminino , Histamina/farmacologia , Antagonistas dos Receptores Histamínicos H1/farmacologia , Liberação de Histamina/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Pele/irrigação sanguínea , Pele/imunologia , Testes Cutâneos , Substância P/farmacologia
13.
Dermatology ; 184(2): 111-5, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1353996

RESUMO

Two double-blind clinical pharmacology studies were performed in atopics in order to compare the inhibitory effects of cetirizine (CTZ) 2 HCl and terfenadine (TER) on histamine and antigen-induced skin reactions. In the first study, the subjects took single intakes of CTZ 10 mg and TER 60 mg. In the second study, they took CTZ 10 mg once a day and TER 60 mg b.i.d. for 3 weeks. CTZ was more effective than TER in inhibiting histamine skin reactivity. CTZ and TER were equally effective in inhibiting antigen-induced reactions. There was no tachyphylaxis, either for CTZ or for TER.


Assuntos
Dermatite/tratamento farmacológico , Antagonistas dos Receptores Histamínicos H1/uso terapêutico , Hidroxizina/análogos & derivados , Hipersensibilidade Imediata/tratamento farmacológico , Testes Cutâneos , Terfenadina/uso terapêutico , Adolescente , Adulto , Antígenos , Cetirizina , Dermatite/etiologia , Método Duplo-Cego , Feminino , Histamina , Antagonistas dos Receptores Histamínicos H1/administração & dosagem , Humanos , Hidroxizina/administração & dosagem , Hidroxizina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Terfenadina/administração & dosagem
14.
J Int Med Res ; 19(2): 174-9, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1677903

RESUMO

In an open, randomized crossover study, the inhibition of histamine-induced weals and flares after one dose of 10 mg cetirizine administered orally or sublingually to seven healthy volunteers was compared. Formation of both weals and flares was significantly inhibited by cetirizine administered by either route; weals were inhibited as early as 20 min after oral intake but not clearly inhibited until 90 min after sublingual intake. There was no clinically relevant difference between the effects of the two routes of administration on flare area. Cetirizine was not well tolerated when given sublingually: two patients reported a burning sensation in the tongue and one reported a local anaesthetic effect. Plasma cetirizine concentrations showed no clear difference between the two routes of administration.


Assuntos
Antagonistas dos Receptores Histamínicos H1/farmacologia , Hidroxizina/análogos & derivados , Urticária/prevenção & controle , Administração Oral , Administração Sublingual , Adulto , Cetirizina , Feminino , Histamina/toxicidade , Antagonistas dos Receptores Histamínicos H1/administração & dosagem , Antagonistas dos Receptores Histamínicos H1/sangue , Humanos , Hidroxizina/administração & dosagem , Hidroxizina/sangue , Hidroxizina/farmacologia , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Fatores de Tempo , Urticária/induzido quimicamente
17.
Ann Allergy ; 65(2): 139-42, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1974399

RESUMO

Histamine-induced wheals and flares were measured in seven healthy volunteers zero, four, and eight hours after oral intake of cetirizine, 2.5, 5, and 10 mg; loratadine, 10, 20, and 40 mg; and placebo. Cetirizine (2.5, 5, and 10 mg) and loratadine (20 and 40 mg) significantly inhibited the histamine-induced wheals at all experimental times and with all histamine concentrations. This was not always the case with loratadine, 10 mg. Cetirizine, 2.5 mg, was as potent in inhibiting the histamine skin reactivity as loratadine, 10 mg.


Assuntos
Ciproeptadina/análogos & derivados , Antagonistas dos Receptores Histamínicos/farmacologia , Antagonistas dos Receptores Histamínicos H1/farmacologia , Hidroxizina/análogos & derivados , Adulto , Cetirizina , Ciproeptadina/farmacologia , Método Duplo-Cego , Hipersensibilidade a Drogas/etiologia , Feminino , Histamina/efeitos adversos , Humanos , Hidroxizina/farmacologia , Hipersensibilidade Imediata/induzido quimicamente , Hipnóticos e Sedativos , Loratadina , Masculino , Pessoa de Meia-Idade , Placebos , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
J Int Med Res ; 18(3): 219-24, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-1972927

RESUMO

In a double-blind, multicentre trial, 105 patients with seasonal allergic rhinitis were treated with 10 mg astemizole or 10 mg cetirizine once daily for 4 days. Patients were thereafter allowed to change their treatment if not satisfied with the clinical efficacy. In the cetirizine-treated group, there were significantly fewer (P = 0.02) patients who asked to change their treatment compared to patients receiving astemizole for 4 days. At day 4, there was a significant improvement in the clinical scores for the patients who did not want to change treatment but scores were hardly altered in those patients that wished to change. After treatment for a further 10 days, there was a decrease in all the scored symptoms but this was less marked in the two groups of patients who wanted to change treatment.


Assuntos
Benzimidazóis/uso terapêutico , Antagonistas dos Receptores Histamínicos H1/uso terapêutico , Hidroxizina/análogos & derivados , Rinite Alérgica Sazonal/tratamento farmacológico , Adulto , Astemizol , Cetirizina , Ensaios Clínicos como Assunto , Método Duplo-Cego , Feminino , Antagonistas dos Receptores Histamínicos H1/efeitos adversos , Humanos , Hidroxizina/efeitos adversos , Hidroxizina/uso terapêutico , Masculino , Estudos Multicêntricos como Assunto , Rinite Alérgica Sazonal/fisiopatologia
20.
J Int Med Res ; 17(1): 24-7, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2565265

RESUMO

In a double-blind study performed in 81 healthy volunteers, 10 mg cetirizine and 60 mg terfenadine given orally in a single administration significantly inhibited skin reactivity to histamine. Astemizole (10 mg) was completely ineffective. The inhibitory effect of cetirizine was potent and regular whereas 6/28 (21%) volunteers did not respond to terfenadine. The difference observed between cetirizine and terfenadine might be due to differences in the metabolism of the two drugs after administration: terfenadine is rapidly and extensively metabolized whereas cetirizine is directly active without the need for biotransformation and, indeed is poorly metabolized.


Assuntos
Compostos Benzidrílicos/farmacologia , Benzimidazóis/farmacologia , Antagonistas dos Receptores Histamínicos H1/farmacologia , Histamina/farmacologia , Hidroxizina/análogos & derivados , Pele/imunologia , Adulto , Astemizol , Cetirizina , Método Duplo-Cego , Humanos , Hidroxizina/farmacologia , Pele/efeitos dos fármacos , Terfenadina
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