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We investigated decays of ^{51,52,53}K at the ISOLDE Decay Station at CERN in order to understand the mechanism of the ß-delayed neutron-emission (ßn) process. The experiment quantified neutron and γ-ray emission paths for each precursor. We used this information to test the hypothesis, first formulated by Bohr in 1939, that neutrons in the ßn process originate from the structureless "compound nucleus." The data are consistent with this postulate for most of the observed decay paths. The agreement, however, is surprising because the compound-nucleus stage should not be achieved in the studied ß decay due to insufficient excitation energy and level densities in the neutron emitter. In the ^{53}K ßn decay, we found a preferential population of the first excited state in ^{52}Ca that contradicted Bohr's hypothesis. The latter was interpreted as evidence for direct neutron emission sensitive to the structure of the neutron-unbound state. We propose that the observed nonstatistical neutron emission proceeds through the coupling with nearby doorway states that have large neutron-emission probabilities. The appearance of "compound-nucleus" decay is caused by the aggregated small contributions of multiple doorway states at higher excitation energy.
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At CERN-ISOLDE, high-purity radioactive ion beams of 219Fr and 221RaF were investigated with α-decay spectroscopy at the CRIS and ASET experiments in the course of three different experimental campaigns. The half-life of 215At, α-decay daughter of 219Fr, is measured to be 36.3(3)[9]µs, and that of 221Ra was determined to be 26.2(1)[6]s, both of which are well in line with the trends in this region of the nuclear landscape but at odds with some of the reported literature.
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The ß decays from both the ground state and a long-lived isomer of ^{133}In were studied at the ISOLDE Decay Station (IDS). With a hybrid detection system sensitive to ß, γ, and neutron spectroscopy, the comparative partial half-lives (logft) have been measured for all their dominant ß-decay channels for the first time, including a low-energy Gamow-Teller transition and several first-forbidden (FF) transitions. Uniquely for such a heavy neutron-rich nucleus, their ß decays selectively populate only a few isolated neutron unbound states in ^{133}Sn. Precise energy and branching-ratio measurements of those resonances allow us to benchmark ß-decay theories at an unprecedented level in this region of the nuclear chart. The results show good agreement with the newly developed large-scale shell model (LSSM) calculations. The experimental findings establish an archetype for the ß decay of neutron-rich nuclei southeast of ^{132}Sn and will serve as a guide for future theoretical development aiming to describe accurately the key ß decays in the rapid-neutron capture (r-) process.
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Kawasaki disease (KD) is a medium vessel systemic vasculitis that predominantly occurs in children below five years of age. It is an acute febrile condition in which coronary artery aneurysms and myocarditis are the most common cardiovascular complications. It is most often characterized by hypercytokinemia. The etiopathogenesis of KD is not fully understood. The present review synthesizes the recent advances in the pathophysiology and treatment options of KD. According to different studies, the genetic, infections and autoimmunity factors play a major role in pathogenesis. Several susceptibility genes (e.g. caspase 3) and cytokines (e.g. IL-2, IL-4, IL-6, IL-10, IFN-gamma and TNF-alpha) have been identified in KD. Patients with high cytokine levels are predisposed to KD shock syndrome. The importance of respiratory viruses in the pathogenesis of the disease is unclear. Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may induce in children and adults an abnormal systemic inflammatory response. This syndrome shares characteristics with KD. It has been called by many terms like MIS-C (Multisystem Inflammatory Syndrome in Children), PIMS-TS (pediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2), hyperinflammatory shock syndrome, cytokine storm (cytokine release syndrome) or simply, Kawasaki-like syndrome. The cytokine's role in the development of KD or Kawasaki-like syndrome being triggered by COVID-19 is controversial. The presences of the antiendothelial cell autoantibodies (AECAs) together with the newly developed hypothesis of immunothrombosis are considered potential pathogenic mechanisms for KD. In consequence, the diagnosis and treatment of KD and Kawasaki-like syndrome, one of the most common causes of acquired heart disease in developed countries, are challenging without a clearly defined protocol.
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COVID-19 , Síndrome de Linfonodos Mucocutâneos , COVID-19/complicações , Criança , Citocinas , Humanos , Síndrome de Linfonodos Mucocutâneos/complicações , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Síndrome de Linfonodos Mucocutâneos/terapia , SARS-CoV-2 , Síndrome de Resposta Inflamatória SistêmicaRESUMO
The low-spin structure of the semimagic ^{64}Ni nucleus has been considerably expanded: combining four experiments, several 0^{+} and 2^{+} excited states were identified below 4.5 MeV, and their properties established. The Monte Carlo shell model accounts for the results and unveils an unexpectedly complex landscape of coexisting shapes: a prolate 0^{+} excitation is located at a surprisingly high energy (3463 keV), with a collective 2^{+} state 286 keV above it, the first such observation in Ni isotopes. The evolution in excitation energy of the prolate minimum across the neutron N=40 subshell gap highlights the impact of the monopole interaction and its variation in strength with N.
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BACKGROUND: The parasite Toxoplasma gondii can cause congenital toxoplasmosis following primary infection in a pregnant woman. It is therefore important to distinguish between recent and past infection when both T. gondii-specific IgM and IgG are detected in a single serum in pregnant women. Toxoplasma gondii-specific IgG avidity testing is an essential tool to help to date the infection. However, interpretation of its results can be complex. OBJECTIVES: To review the benefits and limitations of T. gondii-specific avidity testing in pregnant women, to help practitioners to interpret the results and adapt the patient management. SOURCES: PubMed search with the keywords avidity, toxoplasmosis and Toxoplasma gondii for articles published from 1989 to 2019. CONTENT: Toxoplasma gondii-specific IgG avidity testing remains a key tool for dating a T. gondii infection in immunocompetent pregnant women. Several commercial assays are available and display comparable performances. A high avidity result obtained on a first-trimester serum sample is indicative of a past infection, which occurred before pregnancy. To date, a low avidity result must still be considered as non-informative to date the infection, although some authors suggest that very low avidity results are highly suggestive of recent infections depending on the assay. Interpretation of low or grey zone avidity results on a first-trimester serum sample, as well as any avidity result on a second-trimester or third-trimester serum sample, is more complex and requires recourse to expert toxoplasmosis laboratories. IMPLICATIONS: Although used for about 30 years, T. gondii-specific avidity testing has scarcely evolved. The same difficulties in interpretation have persisted over the years. Some authors have proposed additional thresholds to exclude an infection of <9 months, or in contrast to confirm a recent infection. Such thresholds would be of great interest to adapt management of pregnant women and avoid unnecessary treatment; however, they need confirmation and further studies.
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Afinidade de Anticorpos , Imunoglobulina G/sangue , Complicações Parasitárias na Gravidez/diagnóstico , Toxoplasma/imunologia , Feminino , Humanos , Gravidez , Complicações Parasitárias na Gravidez/parasitologiaRESUMO
A search for shape isomers in the ^{66}Ni nucleus was performed, following old suggestions of various mean-field models and recent ones, based on state-of-the-art Monte Carlo shell model (MCSM), all considering ^{66}Ni as the lightest nuclear system with shape isomerism. By employing the two-neutron transfer reaction induced by an ^{18}O beam on a ^{64}Ni target, at the sub-Coulomb barrier energy of 39 MeV, all three lowest-excited 0^{+} states in ^{66}Ni were populated and their γ decay was observed by γ-coincidence technique. The 0^{+} states lifetimes were assessed with the plunger method, yielding for the 0_{2}^{+}, 0_{3}^{+}, and 0_{4}^{+} decay to the 2_{1}^{+} state the B(E2) values of 4.3, 0.1, and 0.2 Weisskopf units (W.u.), respectively. MCSM calculations correctly predict the existence of all three excited 0^{+} states, pointing to the oblate, spherical, and prolate nature of the consecutive excitations. In addition, they account for the hindrance of the E2 decay from the prolate 0_{4}^{+} to the spherical 2_{1}^{+} state, although overestimating its value. This result makes ^{66}Ni a unique nuclear system, apart from ^{236,238}U, in which a retarded γ transition from a 0^{+} deformed state to a spherical configuration is observed, resembling a shape-isomerlike behavior.
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The N=48 ^{80}Ge nucleus is studied by means of ß-delayed electron-conversion spectroscopy at ALTO. The radioactive ^{80}Ga beam is produced through the isotope separation on line photofission technique and collected on a movable tape for the measurement of γ and e^{-} emission following ß decay. An electric monopole E0 transition, which points to a 639(1) keV intruder 0_{2}^{+} state, is observed for the first time. This new state is lower than the 2_{1}^{+} level in ^{80}Ge, and provides evidence of shape coexistence close to one of the most neutron-rich doubly magic nuclei discovered so far, ^{78}Ni. This result is compared with theoretical estimates, helping to explain the role of monopole and quadrupole forces in the weakening of the N=50 gap at Z=32. The evolution of intruder 0_{2}^{+} states towards ^{78}Ni is discussed.
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UNLABELLED: According to the European Association of Urology guidelines, local periprostatic anesthesia during ultrasound guided biopsy is "state of the art" without specifying the exact benefits and character of choice vs. necessity of this maneuver. AIM: To determine the benefits of using periprostatic anesthesia as standard method of analgesia in patients undergoing transrectal ultrasound guided prostate biopsy. MATERIAL AND METHODS: We conducted a prospective randomized study involving 100 biopsy patients. The patients were randomized in two groups, 50 patients benefiting from local periprostatic anesthesia with 10 ml of lidocaine and the remaining 50 without local anesthesia. In our clinic we use the 12-core prostate biopsy procedure using 18G/20 cm caliber needles. To assess perceived pain intensity during the procedure, immediately after biopsy we applied to patients a VAS questionnaire (Visual Analogue Scale) as a simple method of quantitative evaluation of a symptom the perception of which varies greatly between individuals. RESULTS: A reduction in perceived pain by 45.06% (30.47 vs. 16.74) was recorded in the group receiving local periprostatic anesthesia. It is also worth mentioning that the patients receiving anesthesia said that anesthesia punctures were the most painful (the remaining punctures being much less painful), while patients without anesthesia reported pain intensity levels more or less equal in all 12 performed punctures. CONCLUSIONS: Local anesthesia is a necessity in ultrasound guided prostate biopsies as it significantly reduces pain intensity in patients undergoing this diagnostic procedure.
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Anestesia Local/métodos , Anestésicos Locais/administração & dosagem , Biópsia por Agulha , Lidocaína/administração & dosagem , Próstata/diagnóstico por imagem , Próstata/patologia , Ultrassonografia de Intervenção , Biópsia por Agulha/métodos , Humanos , Masculino , Satisfação do Paciente , Estudos Prospectivos , Reto , Inquéritos e Questionários , Ultrassonografia de Intervenção/métodosRESUMO
AIM: To evaluate our experience with the first cases of radical retropubic prostatectomy and to use the results for patient counseling and optimizing therapeutic decision. MATERIAL AND METHODS: In the interval January 2011 - December 2012, 23 patients aged 56-69 years (mean age 62.6 years) were treated by radical retropubic prostatectomy. The retrospective study included an analysis of the significant data in the case records, surgical protocols and outpatient postoperative check-ups, special attention being given to indications, intra- and early postoperative complications (within 30 days) and hospital stay. RESULTS: Preoperatively, prostate specific antigen (PSA) ranged between 4.5 and 27.2 ng/ml (mean 9.5 ng/ml), and Gleason score was 5 in one patient, 6 in 20, and 7 in 2 patients. Clinical stage was T1 in 5 patients (21.7%), T2 in 16 (69.6%) and T3 in 2 (8.7%). Mean intraoperative blood loss was 1214 ml (range 400-2500 ml), and 17 patients received blood transfusions. Postoperative complications included acute renal failure and extravasation of contrast medium during retrograde cystography in 3 cases each, urinary infection in 4 patients and wound dehiscence in 1 case. The average postoperative hospital stay was 19.57 days (range 13-43). CONCLUSIONS: Radical retropubic prostatectomy is a safe technique, involving a reduced risk of complications. For most patients with localized prostate cancer, radical prostatectomy is the best treatment option.
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Biomarcadores Tumorais/sangue , Antígeno Prostático Específico/sangue , Prostatectomia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/cirurgia , Idoso , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Prostatectomia/efeitos adversos , Prostatectomia/métodos , Neoplasias da Próstata/sangue , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Resultado do TratamentoRESUMO
OBJECTIVES: The study aimed to identify the complications recorded at the patients with obstructive renal failure treated with percutaneous nephrostomy (PCN). MATERIAL AND METHOD: The retrospective study investigated the data of 244 patients admitted in our department and treated with percutaneous nephrostomy for obstructive renal failure during January 2005 - December 2007. Demographical data, investigation, indication, complications and hospital stay were recorded. RESULTS: Median preoperative/discharge haematological values were hematocrit 27.4% comparing to 25.8% and haemoglobin 9.9g% comparing to 9.3g%. An anaemic syndrome was noted at admission time in 161 (65.9%) patients and at discharge time 202 (82.8%). 126 (51.6%) patients were treated with blood transfusion with an average dose of 2.47 red blood cell units per patient. In 25 (10.1%) patients the nefrostomy tube was clamped in order to control the postoperative bleeding. The median hospitalization time was 8.7 days with a median ICU stay of 3.3 days. The recorded mortality was 3.2% (8 patients) with an average time of 5.8 days between the operatory time and exitus time. CONCLUSIONS: The most frequent causes of obstructive renal failure necessiting percutaneous nephrostomy are malignancies. Preoperative anaemic syndrome is aggravated in the postoperative period and frequently need red blood cell administration. In experienced hands, PCN catheter placement is safe and usually successful.
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Injúria Renal Aguda/etiologia , Nefrostomia Percutânea/efeitos adversos , Obstrução Ureteral/complicações , Injúria Renal Aguda/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia Ferropriva/etiologia , Anemia Ferropriva/terapia , Transfusão de Sangue , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Hemorragia Pós-Operatória/etiologia , Estudos Retrospectivos , Romênia/epidemiologia , População Rural/estatística & dados numéricos , Taxa de Sobrevida , Resultado do Tratamento , População Urbana/estatística & dados numéricos , Obstrução Ureteral/mortalidade , Obstrução Ureteral/cirurgiaRESUMO
In the urine of a patient with chronic prostatitis, renal microlithiasis and acute cystitis we found the ciliate protozoa Colpoda spp., both in vegetative and cystic form. The entry point was most likely the urinary tract. Keeping in mind that only four more cases of Colpoda spp. existent in human urine have already been described, and that in the case of our patient the ciliate was present at repeated examinations of his urine, we presumed that it is not only a spurious infection of the urogenital tract. It still remains to be analyzed whether this ciliate belongs to a species of Colpoda adapted to parasitism in homeothermae and whether it can be pathogenic for humans.
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Ureteroscopy is a well-established procedure, which has proven the efficiency for diagnostic purposes, but mostly for ureteric stone removal. The authors describe their strategy after ureteroscopic lithotripsy with Wolf 8 Ch semirigid ureteroscope. Insertion of a double J stent for 2-4 weeks was the rule when there was an important bleeding during the procedure, the fragments were big and could not be extracted, some fragments migrated in upper third of the ureter or renal pelvis, a perforation occurred or it was found a ureteral stenosis. If the stone can be extracted without any problems (in one piece) and the ureter is normal there is no need for ureteral stenting. Having in mind that many patients describe problems with the double J stent (pains, polakiuria, etc) we recommend to insert a stent at the end of ureteroscopy only for selected cases.
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Stents , Cálculos Ureterais/terapia , Ureteroscopia/métodos , Humanos , Litotripsia , Estudos Retrospectivos , Resultado do Tratamento , Cálculos Ureterais/diagnóstico , UrologiaRESUMO
The aim of this study was to evaluate the internal urethrotomy in the treatment of urethral strictures, by the retrospective analysis of 54 cases. The patients' age ranged between 18-92. 35 patients (64.8%) had iatrogenic strictures and 10 (18.5%) had traumatic ones. 35 patients presented with urinary infections before the procedure. Following internal urethrotomy, the medium hospital stay was 3.15 days. There were only 7 patients with postoperative fever and no death was recorded. The follow-up period was between 1-12 months with a medium of 9 months and only 2 patients required recurrent internal urethrotomy. Out of the 54 patients, 8 had recurrent urethral stricture disease and 6 of them had posttraumatic membranous urethral strictures. Optical internal urethrotomy appears to be the ideal therapeutic method of urethral strictures, because it has a low morbidity, it is safe to perform and the postoperative results are good. The hospitalization and the recovery periods are short, allowing a quick socio-professional reintegration. Most of the recurrencies occur with posttraumatic strictures.
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Estreitamento Uretral/cirurgia , Procedimentos Cirúrgicos Urológicos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Estreitamento Uretral/etiologiaRESUMO
With the aim of the evaluation of cystography as a diagnostic method, this study has retrospectively analysed 22 cases of bladder rupture (19) or perforation (3). When performed, the retrograde cystography has made the accurate diagnosis immediately in all the 15 cases (100%). The adequate filling and the x-rays made after the bladder evacuation are the main conditions, that allow the visualisation of the contrast material extravasation. Out of the remaining 7 cases, the urographic cystography has made the correct diagnosis in 6 of them (86%) and the method should be indicated in cases with concomitant rupture of the membranous urethra.
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Cistoscopia , Bexiga Urinária/diagnóstico por imagem , Bexiga Urinária/lesões , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Ruptura , Sensibilidade e EspecificidadeRESUMO
The authors present their experience of 122 partial cystectomy cases made on a number of 288 vesical tumors in our clinic, during 5 years (1986-1991) from which 23 are superficial tumors and 99 are infiltrative ones. The treatment of vesical tumors can be done in many ways; this partial cystectomy must be completed with an other therapeutic method: irradiation on chemotherapy in conformity with the anatomo-pathological form, the steady and tumoral grading.