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The decay path of the Hoyle state in ^{12}C (E_{x}=7.654 MeV) has been studied with the ^{14}N(d,α_{2})^{12}C(7.654) reaction induced at 10.5 MeV. High resolution invariant mass spectroscopy techniques have allowed us to unambiguously disentangle direct and sequential decays of the state passing through the ground state of ^{8}Be. Thanks to the almost total absence of background and the attained resolution, a fully sequential decay contribution to the width of the state has been observed. The direct decay width is negligible, with an upper limit of 0.043% (95% C.L.). The precision of this result is about a factor 5 higher than previous studies. This has significant implications on nuclear structure, as it provides constraints to 3α cluster model calculations, where higher precision limits are needed.
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A detailed knowledge of the decay properties of the so called Hoyle state in the 12 C nucleus ( E x = 7.654 MeV, 0 + ) is required to calculate the rate at which carbon is forged in typical red-giant stars. This paper reports on a new almost background-free measurement of the radiative decay branching ratio of the Hoyle state using advanced charged particle coincidence techniques. The exploitation, for the first time in a similar experiment, of a bidimensional map of the coincidence efficiency allows to reach an unitary value and, consequently, to strongly reduce sources of systematic uncertainties. The present results suggest a value of the radiative branching ratio of Γ rad / Γ tot = 4.4 ( 6 ) · 10 - 4 . This finding helps to resolve the tension between recent data published in the literature.
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Alice in Wonderland Syndrome (AIWS) is a rare perceptual disorder, rarely associated with epileptic etiology. We report the case of a 23-year-old man with subacute onset of right peri-orbital headache and visual misperceptions consistent with AIWS Type B, who underwent laboratory tests, brain CT with venography, ophthalmic examination, and neurological assessment that turned out to be normal except for visuospatial difficulties and constructional apraxia. A nasopharyngeal SARS-CoV2 swab taken as screening protocol was positive. The EEG performed because of the persistence of AIWS showed a focal right temporo-occipital non-convulsive status epilepticus; a slow resolution of clinical and EEG alterations was achieved with anti-seizure medications. Brain MRI showed right cortical temporo-occipital signal abnormalities consistent with peri-ictal changes and post-contrast T1 revealed a superior sagittal sinus thrombosis, thus anticoagulant therapy was initiated. AIWS is associated with temporo-parieto-occipital carrefour abnormalities, where visual and somatosensory inputs are integrated to generate the representation of body schema. In this patient, AIWS is caused by temporo-occipital status epilepticus without anatomical and electroencephalographic involvement of the parietal region, consistent with the absence of somatosensory symptoms of the syndrome. Status epilepticus can be the presenting symptom of cerebral venous sinus thrombosis (CVST) which, in this case, is possibly due to the hypercoagulable state associated with COVID-19.
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The aim of this study was to assess the prevalence of non toxic goiter, difuse or nodular, in all Genoa's Country thyroid diseases. The authors have studied one non-random casuistry of 1980 Patients observed from time to time in the last decade in Ambulatory of Nuclear Medicine (Department of Internal Medicine of University of Genoa) working with Section of Hygiene of ASL of Genoa. Of 1980 patients, 1629 (83.63%) were females; 351 (16.37%) were males, aged 14-70 years. The mean age was 42.6 years. First observations regarded only born and old date residents in Genoa never subordinates to surgical. Actinic or pharmacological treatments to the thyroid. All patients have normal circulating hormones and TSH. Every subject was afflicted with un toxic goiter (diffuse, single nodular or multi nodular) assessed by clinical Examination, ultrasonography and thyroid uptake with 99mTc-pertechnetate. This pathology represents now the 66.6% of all thyroid diseases observed. The A.A. emphasized an absolute prevalence of non toxic goiter in females (84.2% of observations). The enclosed tables are created divided the casuistry for age correspondents to the several decades (for the II to VII the wais). By means of the test of Kolmogorov-Smirnov we have shaped two delineating curves the frequencies. Accumulated of feminine and male subjects. The results of our study support a advantage of the Females versus male subjects in the diffuse and in the multi nodular goiter, while in the Struma to Single nodular differences are meaningful absent.
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Bócio Nodular/diagnóstico , Bócio Nodular/epidemiologia , Nível de Saúde , Índice de Gravidade de Doença , Adolescente , Adulto , Distribuição por Idade , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Distribuição por Sexo , Adulto JovemRESUMO
To evaluate the postulated role of extrastriatal D1 receptors in human cognition and psychopathology requires an accurate and reliable method for quantification of these receptors in the living human brain. [11C]NNC 112 is a promising novel radiotracer for positron emission tomography imaging of the D1 receptor. The goal of this study was to develop and evaluate methods to derive D1 receptor parameters in striatal and extrastriatal regions of the human brain with [11C]NNC 112. Six healthy volunteers were studied twice. Two methods of analysis (kinetic and graphical) were applied to 12 regions (neocortical, limbic, and subcortical regions) to derive four outcome measures: total distribution volume, distribution volume ratio, binding potential (BP), and specific-to-nonspecific equilibrium partition coefficient (k3/k4). Both kinetic and graphic analyses provided BP and k3/k4 values in good agreement with the known distribution of D1 receptors (striatum > limbic regions = neocortical regions > thalamus). The identifiability of outcome measures derived by kinetic analysis was excellent. Time-stability analysis indicated that 90 minutes of data collection generated stable outcome measures. Derivation of BP and k3/k4 by kinetic analysis was highly reliable, with intraclass correlation coefficients (ICCs) of 0.90+/-0.06 (mean +/- SD of 12 regions) and 0.84+/-0.11, respectively. The reliability of these parameters derived by graphical analysis was lower, with ICCs of 0.72+/-0.17 and 0.58+/-0.21, respectively. Noise analysis revealed a noise-dependent bias in the graphical but not the kinetic analysis. In conclusion, kinetic analysis of [11C]NNC 112 uptake provides an appropriate method with which to derive D1 receptor parameters in regions with both high (striatal) and low (extrastriatal) D1 receptor density.
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Benzazepinas , Benzofuranos , Corpo Estriado/metabolismo , Receptores de Dopamina D1/metabolismo , Tomografia Computadorizada de Emissão/normas , Adulto , Artefatos , Benzazepinas/sangue , Benzazepinas/farmacocinética , Benzofuranos/sangue , Benzofuranos/farmacocinética , Radioisótopos de Carbono , Cerebelo/química , Cerebelo/diagnóstico por imagem , Cerebelo/metabolismo , Corpo Estriado/química , Corpo Estriado/diagnóstico por imagem , Antagonistas de Dopamina/farmacocinética , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Neocórtex/química , Neocórtex/diagnóstico por imagem , Neocórtex/metabolismo , Ensaio Radioligante/métodos , Ensaio Radioligante/normas , Reprodutibilidade dos Testes , Tomografia Computadorizada de Emissão/métodosRESUMO
In some laboratories hair testing may be the main method for the evaluation of individual's drug history, however, compelling evidence supports the possibility that the presence of a small amount of drug in hair can derive from external contamination. The aim of the present study is to verify if a single external contamination with a small amount of cocaine will last sufficiently long to make a contaminated subject indistinguishable from active users, and if normal washing practices together with the decontamination procedures are sufficient to completely remove the external contamination. The results obtained using the decontamination methods suggested in literature demonstrate that significant concentrations of cocaine (>1 ng/mg) and moderate quantities of benzoylecgonine (generally <0.5 ng/mg) are still detectable up to 10 weeks after contamination. These results question the reliability of hair testing. In fact, even using the most sophisticated decontamination procedures it is not possible to distinguish a drug-contaminated subject from an active user. Thus, while a negative result excludes both chronic use and "contact" with drugs, a positive result cannot and must not be interpreted as a sure sign of drug addiction, but should be further confirmed by urine analysis.
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Transtornos Relacionados ao Uso de Cocaína/diagnóstico , Cocaína/análogos & derivados , Cocaína/análise , Cabelo/química , Detecção do Abuso de Substâncias/métodos , Reações Falso-Positivas , Cromatografia Gasosa-Espectrometria de Massas , HumanosRESUMO
BACKGROUND: Dysphoric mania is a common and often difficult to treat subset of bipolar mania that is associated with significant depressive symptoms. OBJECTIVE: This post hoc analysis was designed to evaluate the efficacy of ziprasidone in the treatment of depressive and other symptoms in a cohort of patients with dysphoric mania. METHODS: Pooled data were examined from two similarly designed, 3-week placebo-controlled trials in acute bipolar mania. Patients scoring >/=2 on at least two items of the extracted Hamilton Rating Scale for Depression (HAM-D) met criteria for dysphoric mania and were included in the post hoc analysis. Changes from baseline in symptom scores were evaluated by a mixed-model analysis of covariance. RESULTS: 179 patients with dysphoric mania were included in the post hoc analysis (ziprasidone, n=124; placebo, n=55). Beginning at day 4, HAM-D scores were significantly lower at all visits in patients treated with ziprasidone compared with those treated with placebo (p<0.05). Ziprasidone-treated patients also demonstrated significant improvements on the Mania Rating Scale and all secondary efficacy measures, and had significantly higher response and remission rates compared with placebo. LIMITATIONS: The main limitations are the use of a post hoc analysis and the pooling of two studies with slightly different designs. CONCLUSION: In this analysis, ziprasidone significantly improved both depressive and manic mood symptoms in patients with dysphoric mania, suggesting that it might be a useful treatment option in this patient population. Further prospective controlled trials are needed to confirm these findings.
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Transtorno Bipolar/tratamento farmacológico , Depressão/tratamento farmacológico , Piperazinas/uso terapêutico , Tiazóis/uso terapêutico , Doença Aguda , Adulto , Afeto/efeitos dos fármacos , Idoso , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/psicologia , Depressão/diagnóstico , Depressão/psicologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Piperazinas/efeitos adversos , Escalas de Graduação Psiquiátrica , Tiazóis/efeitos adversosRESUMO
40Ca+;{40,48}Ca,46Ti reactions at 25 MeV/nucleon have been studied using the 4pi CHIMERA detector. An isospin effect on the competition between fusionlike and binarylike reaction mechanisms has been observed. The probability of producing a heavy residue is lower in the case of N approximately Z colliding systems as compared to the case of reactions induced on the neutron rich 48Ca target. Predictions based on constrained molecular dynamics II calculations show that the competition between fusionlike and binary reactions in the selected centrality bins can constrain the parametrization of the symmetry energy and its density dependence in the nuclear equation of state.
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Isotope nephrography is nowadays widely applied to the study of renal transplants. Major advantages of this technique have been obtained for the prognostic evaluation of transplant rejection and in the differential diagnosis of oliguria and anuria. The authors report on 14 cases of renal transplant recipients examined with renal scintigraphy 3-4 days after surgery. In agreement with literature data, the authors wish to stress the importance of the correct use of different tracers (DTPA, MAG3) for renal scintigraphy and nephrography. Problems and complications in renal transplants are studied with the simultaneous use of these tracers. The evaluation of renal blood flow and vascular complications requires radiopharmaceutical DTPA, which is excreted only by glomerular filtration. In contrast to 99mTc-DTPA, 99mTc-MAG3 is now the tracer of choice in the evaluation of tubular function. Some problems are still to be solved regarding patients management, such as the necessary chronologic relationship between surgical phases and nephrographic/scintigraphic examinations and early and late follow-up of renal transplant recipients.
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Transplante de Rim , Cuidados Pós-Operatórios/métodos , Complicações Pós-Operatórias/diagnóstico por imagem , Adulto , Criança , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/fisiopatologia , CintilografiaRESUMO
In the shark, C-type natriuretic peptide (CNP) is the only cardiac natriuretic hormone identified and is a potent activator of Cl- secretion in the rectal gland, an epithelial organ of this species that contains cystic fibrosis transmembrane conductance regulator (CFTR) Cl- channels. We have cloned an ancestral CNP receptor (NPR-B) from the shark rectal gland that has an overall amino acid identity to the human homologue of 67%. The shark sequence maintains six extracellular Cys present in other NPR-B but lacks a glycosylation site and a Glu residue previously considered important for CNP binding. When shark NPR-B and human CFTR were coexpressed in Xenopus oocytes, CNP increased the cGMP content of oocytes (EC50 12 nM) and activated CFTR Cl- channels (EC50 8 nM). Oocyte cGMP increased 36-fold (from 0.11 +/- 0.03 to 4.03 +/- 0.45 pmol/oocyte) and Cl- current increased 37-fold (from -34 +/- 14 to -1,226 +/- 151 nA) in the presence of 50 nM CNP. These findings identify the specific natriuretic peptide receptor responsible for Cl- secretion in the shark rectal gland and provide the first evidence for activation of CFTR Cl- channels by a cloned NPR-B receptor.
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Clonagem Molecular , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Guanilato Ciclase , Receptores do Fator Natriurético Atrial/genética , Receptores do Fator Natriurético Atrial/metabolismo , Glândula de Sal/metabolismo , Sequência de Aminoácidos/genética , Animais , Cloretos/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/fisiologia , Cação (Peixe) , Eletrofisiologia , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Nucleotídeos Cíclicos/metabolismo , Oócitos/metabolismo , RNA Mensageiro/metabolismo , Receptores do Fator Natriurético Atrial/fisiologia , XenopusRESUMO
The safety and tolerability of carvedilol, a new antihypertensive agent with the combined pharmacological activities of beta-blockade and vasodilation, and of nifedipine were investigated in patients with essential hypertension and non-insulin-dependent (type II) diabetes mellitus. Twenty patients were openly randomized to receive 25 mg carvedilol once daily (five men and five women; mean age, 63 years) or 10 mg nifedipine t.i.d. (three men and seven women; mean age, 64 years) for a period of 4 weeks. Baseline mean sitting blood pressures were 168/98 and 169/95 mm Hg in the carvedilol and nifedipine groups, respectively. Baseline mean areas under the curve (AUC) of the intravenous glucose tolerance test (IVGTT) for the carvedilol and nifedipine groups were 6,136 +/- 1,195 and 6,287 +/- 1,228 mg/dl/min, respectively. Demographic and efficacy variables were not statistically different between treatment groups. After 4 weeks of therapy, mean sitting blood pressure was significantly (p less than 0.02) reduced to 144/91 mm Hg in the carvedilol group and to 149/87 mm Hg in the nifedipine group. Week 4 IVGTT AUC values of 5,735 +/- 1,464 mg/dl/min in the carvedilol group and 5,988 +/- 993 mg/dl/min in the nifedipine group, representing mean reductions of 6.14% and 3.17%, respectively, were not statistically different from baseline. Both treatments were well tolerated. No patient experienced adverse events in the carvedilol treatment group, whereas two patients in the nifedipine group reported episodes of headache (one patient) and palpitations (one patient); each episode was mild in severity and considered to be related to study medication.(ABSTRACT TRUNCATED AT 250 WORDS)
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Antagonistas Adrenérgicos beta/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Carbazóis/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Hipertensão/tratamento farmacológico , Nifedipino/uso terapêutico , Propanolaminas/uso terapêutico , Antagonistas Adrenérgicos beta/efeitos adversos , Idoso , Anti-Hipertensivos/efeitos adversos , Pressão Sanguínea/efeitos dos fármacos , Carbazóis/efeitos adversos , Carvedilol , Feminino , Teste de Tolerância a Glucose , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Nifedipino/efeitos adversos , Propanolaminas/efeitos adversos , Vasodilatadores/efeitos adversos , Vasodilatadores/uso terapêuticoRESUMO
NNC 756 ((+)-8-chloro-5-(2,3-dihydrobenzofuran-7-yl)-7-hydroxy-3-methyl-2,3,4,5- tetrahydro-1H-3-benzazepine) is a new high affinity dopamine (DA) D1 receptor antagonist. Labeled with C-11, it has been used as a PET radiotracer to visualize D1 receptors both in striatal and extrastriatal areas, such as the prefrontal cortex. The goal of this study was to evaluate several methods for derivation of D1 receptor binding potential (BP) with [11C]NNC 756 in baboons, and to use these methods to assess the vulnerability of [11C]NNC 756 binding to competition by endogenous DA. A three-compartment model provided a good fit to PET data acquired following a single bolus injection. BP values obtained with this analysis were in good agreement with values derived from in vitro studies. BP values measured following injection of the potent DA releaser amphetamine (1 mg/kg, n=2) were similar to values measured under control conditions. Kinetic parameters derived from single bolus experiments were used to design a bolus plus continuous infusion administration protocol aimed at achieving a state of sustained binding equilibrium. Injection of amphetamine during sustained equilibrium did not affect [11C]NNC 756 binding. Similar results were observed with another D1 radiotracer, [11C]SCH 23390. Doses of amphetamine used in this study are known to reduce by 20-40% the binding potential of several D2 receptors radiotracers. Therefore, the absence of displacement of [11C]NNC 756 by an endogenous DA surge may indicate important differences between D1 and D2 receptors in vivo, such as differences in proportion of high affinity states not occupied by DA at baseline. These findings may also imply that a simple binding competition model is inadequate to account for the effects of manipulation of endogenous DA levels on the in vivo binding of radiolabeled antagonists.