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1.
Phys Rev Lett ; 126(7): 072501, 2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33666458

RESUMEN

We studied the proton-rich T_{z}=-1 nucleus ^{70}Kr through inelastic scattering at intermediate energies in order to extract the reduced transition probability, B(E2;0^{+}→2^{+}). Comparison with the other members of the A=70 isospin triplet, ^{70}Br and ^{70}Se, studied in the same experiment, shows a 3σ deviation from the expected linearity of the electromagnetic matrix elements as a function of T_{z}. At present, no established nuclear structure theory can describe this observed deviation quantitatively. This is the first violation of isospin symmetry at this level observed in the transition matrix elements. A heuristic approach may explain the anomaly by a shape change between the mirror nuclei ^{70}Kr and ^{70}Se contrary to the model predictions.

2.
Phys Rev Lett ; 122(22): 222502, 2019 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-31283269

RESUMEN

A record number of ^{100}Sn nuclei was detected and new isotopic species toward the proton dripline were discovered at the RIKEN Nishina Center. Decay spectroscopy was performed with the high-efficiency detector arrays WAS3ABi and EURICA. Both the half-life and the ß-decay end point energy of ^{100}Sn were measured more precisely than the literature values. The value and the uncertainty of the resulting strength for the pure 0^{+}→1^{+} Gamow-Teller decay was improved to B_{GT}=4.4_{-0.7}^{+0.9}. A discrimination between different model calculations was possible for the first time, and the level scheme of ^{100}In is investigated further.

3.
Unfallchirurg ; 120(2): 167-170, 2017 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-27757484

RESUMEN

One representative case of burns caused by the negligent use of bioethanol, which was treated at our burns centre is used to illustrate the severity and depth of the burn injuries as well as the complexity of the further long-term course of treatment including complex secondary-reconstructive techniques.


Asunto(s)
Quemaduras/etiología , Quemaduras/cirugía , Etanol , Procedimientos de Cirugía Plástica/métodos , Piel/lesiones , Colgajos Quirúrgicos , Accidentes Domésticos , Adulto , Quemaduras/diagnóstico , Terapia Combinada/métodos , Procedimientos Quirúrgicos Dermatologicos/métodos , Femenino , Humanos , Mala Praxis , Prevención Secundaria/métodos , Piel Artificial , Resultado del Tratamiento
4.
Phys Rev Lett ; 116(16): 162501, 2016 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-27152796

RESUMEN

Several new isotopes, ^{96}In, ^{94}Cd, ^{92}Ag, and ^{90}Pd, have been identified at the RIKEN Nishina Center. The study of proton drip-line nuclei in the vicinity of ^{100}Sn led to the discovery of new proton emitters ^{93}Ag and ^{89}Rh with half-lives in the submicrosecond range. The systematics of the half-lives of odd-Z nuclei with T_{z}=-1/2 toward ^{99}Sn shows a stabilizing effect of the Z=50 shell closure. Production cross sections for nuclei in the vicinity of ^{100}Sn measured at different energies and target thicknesses were compared to the cross sections calculated by epax taking into account contributions of secondary reactions in the primary target.

5.
Phys Rev Lett ; 117(16): 162501, 2016 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-27792367

RESUMEN

In an experiment with the BigRIPS separator at the RIKEN Nishina Center, we observed two-proton (2p) emission from ^{67}Kr. At the same time, no evidence for 2p emission of ^{59}Ge and ^{63}Se, two other potential candidates for this exotic radioactivity, could be observed. This observation is in line with Q value predictions which pointed to ^{67}Kr as being the best new candidate among the three for two-proton radioactivity. ^{67}Kr is only the fourth 2p ground-state emitter to be observed with a half-life of the order of a few milliseconds. The decay energy was determined to be 1690(17) keV, the 2p emission branching ratio is 37(14)%, and the half-life of ^{67}Kr is 7.4(30) ms.

6.
Phys Rev Lett ; 112(22): 222501, 2014 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-24949762

RESUMEN

We report the observation of a very exotic decay mode at the proton drip line, the ß-delayed γ-proton decay, clearly seen in the ß decay of the T_{z}=-2 nucleus ^{56}Zn. Three γ-proton sequences have been observed after the ß decay. Here this decay mode, already observed in the sd shell, is seen for the first time in the fp shell. Both γ and proton decays have been taken into account in the estimation of the Fermi and Gamow-Teller strengths. Evidence for fragmentation of the Fermi strength due to strong isospin mixing is found.

7.
Phys Rev Lett ; 107(10): 102502, 2011 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-21981498

RESUMEN

The two protons emitted in the decay of 54Zn have been individually observed for the first time in a time projection chamber. The total decay energy and the half-life measured in this work agree with the results obtained in a previous experiment. Angular and energy correlations between the two protons are determined and compared to theoretical distributions of a three-body model. Within the shell model framework, the relative decay probabilities show a strong contribution of the p2 configuration for the two-proton emission. After 45Fe, the present result on 54Zn constitutes only the second case of a direct observation of the ground state two-proton decay of a long-lived isotope.

8.
Nat Commun ; 12(1): 4805, 2021 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-34376669

RESUMEN

Proton radioactivity was discovered exactly 50 years ago. First, this nuclear decay mode sets the limit of existence on the nuclear landscape on the neutron-deficient side. Second, it comprises fundamental aspects of both quantum tunnelling as well as the coupling of (quasi)bound quantum states with the continuum in mesoscopic systems such as the atomic nucleus. Theoretical approaches can start either from bound-state nuclear shell-model theory or from resonance scattering. Thus, proton-radioactivity guides merging these types of theoretical approaches, which is of broader relevance for any few-body quantum system. Here, we report experimental measurements of proton-emission branches from an isomeric state in 54mNi, which were visualized in four dimensions in a newly developed detector. We show that these decays, which carry an unusually high angular momentum, ℓ = 5 and ℓ = 7, respectively, can be approximated theoretically with a potential model for the proton barrier penetration and a shell-model calculation for the overlap of the initial and final wave functions.

10.
Clin Hemorheol Microcirc ; 64(3): 333-344, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28128750

RESUMEN

BACKGROUND: The reconstruction of metacarpal- and interphalangeal joints after severe hand injuries has been proven to be challenging. Commonly used procedures like arthrodesis, amputation or ray resection of the finger compromise the functionality of the injured finger. Especially for young patients, the restoration of all functions of the fingers is a priority. Local tissue transfers for finger joint reconstructions is not an option due to inacceptable donor site morbidity; microsurgical tissue transfers in terms of free toe joint transfers have proven to be a valuable method. METHODS: We present the case of a patient who suffered an excessive injury from a circular saw to his dominant hand. The MCP Joints of D2-D4 were fully destroyed, along with the PIP joint of a subtotally amputated D4. Arteries, nerves and tendons could be coapted directly, while primarily reconstructing of the finger joints was impossible. To ensure a possible regain of full functionality, two coherent joints, the MTP and the PIP of one toe, were transferred to the ring finger as a single transplant, reconstructing the MCP and the PIP joints of the injured finger in a one step procedure. Additionally the MCP joint of the D2 was reconstructed by the use of a free PIP-joint transfer, further the MCP joint of the D3 was replaced by an MCP endoprosthesis. RESULTS: After a follow up of 3 years the patient displayed full function of his dominant hand including sensitivity, and has gone back to manual work without limitations. The result was cosmetically acceptable and the donor site defect was easily being tolerated by the patient who is playing soccer in the regional soccer league. CONCLUSION: Free double toe joint transfer has been proven feasible in this patient. While transferring a single toe joint to reconstruct a finger joint is a well-established method, our review of the latest literature showed no case of a free transfer of two coherent joints and three transplanted joints in one hand. The applied microsurgical technique should be considered by microsurgically trained hand surgeons for the treatment of comparable severe hand injuries. In comparison to the most common procedures described for the repair and reconstruction of severely injured finger joints this method showed superior results.


Asunto(s)
Dedos/trasplante , Articulación Metacarpofalángica/cirugía , Articulación del Dedo del Pie/cirugía , Adolescente , Humanos , Masculino , Articulación del Dedo del Pie/patología
11.
Arch Intern Med ; 160(13): 1993-9, 2000 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-10888973

RESUMEN

BACKGROUND: Abnormalities in cardiac function, eg, arrhythmias and congestive heart failure, often accompany thyrotoxicosis. A relationship between thyroid hormone excess and the cardiac complications of angina pectoris and myocardial infarction (MI) remains largely speculative. METHODS: The results of thyroid function studies on blood samples drawn from a total of 1049 patients (aged 40 years or older) immediately on emergency medical admission were related to frequencies of angina pectoris and myocardial infarction as determined according to current diagnostic algorithms. After 3 years, those patients who had initially presented with angina pectoris or acute MI were observed for subsequent coronary events; of these (n=185), 98% of the subjects (n=181) could be reevaluated. RESULTS: On hospital admission, the relative rate of angina pectoris and MI was markedly high (odds ratio, 2.6; 95% confidence interval, 1.3-5.2; P=.007) in patients with elevated serum free and total triiodothyronine (T(3)) levels. An initially elevated free T(3) level was a risk factor for subsequent coronary events during the 3-year follow-up (adjusted odds ratio, 4.8; 95% confidence interval, 1.3-17.4; P=.02). CONCLUSIONS: An elevation of serum free T(3) levels at hospital admission is associated with a 2.6-fold greater likelihood of the presence of a coronary event. Moreover, an initially elevated T(3) level is associated with a 3-fold higher risk of developing a subsequent coronary event during the next 3 years. Excess T(3) seemed to be a factor associated with the development and progression of acute myocardial ischemia.


Asunto(s)
Angina de Pecho/etiología , Infarto del Miocardio/etiología , Triyodotironina/sangre , Adulto , Anciano , Anciano de 80 o más Años , Angina de Pecho/sangre , Angina de Pecho/diagnóstico , Estudios Transversales , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Infarto del Miocardio/sangre , Infarto del Miocardio/diagnóstico , Oportunidad Relativa , Factores de Riesgo , Tirotropina/sangre , Tiroxina/sangre
12.
AIDS ; 13(18): 2533-9, 1999 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-10630522

RESUMEN

OBJECTIVE: To evaluate the ability of a quantified pp65-antigenemia assay to predict the development of human cytomegalovirus (HCMV) disease in patients with an advanced HIV infection. DESIGN: A prospective longitudinal study between March 1993 and December 1996. Blood samples for the pp65-antigenemia assay were drawn at 2-3 month intervals. SETTING: AIDS department of an institutional tertiary care centre. PATIENTS: A total of 101 HIV-infected patients with CD4 lymphocyte counts of 100/mm3 or less were enrolled. Ninety-seven patients were eligible for analysis. All patients gave informed consent. MAIN OUTCOME MEASURES: The development of HCMV disease. RESULTS: Of the 97 patients, 24 developed HCMV disease after a median follow-up of 10.6 months. Three months before the development of HCMV disease, an increase in the median number of pp65-antigen-positive leukocytes was observed. The highest combination of sensitivity (45%) and specificity (94%) for the development of HCMV disease within the next 3 months was found when an assay cut-off level of 48/10(5) pp65-antigen-positive leukocytes was applied, with a positive predictive value (PPV) for the development of HCMV disease of 75%. The Kaplan-Meier estimate of HCMV disease-free survival after patients reached 48/10(5) or more antigen-positive leukocytes on longitudinal follow-up was a median 3.7 months [95% confidence interval (CI), 2.5-8.5]. The hazard ratio (HR) of this threshold level for the development of HCMV disease was 9.6 (95% CI, 4.2-21.8). CONCLUSION: Longitudinal follow-up using the pp65-antigenemia assay of HIV-infected patients with a low CD4 lymphocyte count improves the identification of patients who will develop HCMV disease in the foreseeable future, and should be considered for the selection of patients who may benefit from pre-emptive HCMV treatment.


Asunto(s)
Antígenos Virales/inmunología , Infecciones por Citomegalovirus/inmunología , Infecciones por VIH/inmunología , VIH-1 , Fosfoproteínas/inmunología , Proteínas de la Matriz Viral/inmunología , Adulto , Antígenos Virales/sangre , Linfocitos T CD4-Positivos/inmunología , Infecciones por Citomegalovirus/etiología , Femenino , Infecciones por VIH/complicaciones , Humanos , Masculino , Fosfoproteínas/sangre , Valor Predictivo de las Pruebas , Estudios Prospectivos , Sensibilidad y Especificidad , Pruebas Serológicas , Análisis de Supervivencia , Proteínas de la Matriz Viral/sangre
13.
J Med Chem ; 23(8): 837-40, 1980 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7401111

RESUMEN

1,2,3,4-Tetrahydroisoquinoline-7-sulfonanilides (1-14) related to 1,2,3,4-tetrahydroisoquinoline-7-sulfonamide (21,SK&F 29661) were prepared and studied for their ability to inhibit phenylethanolamine N-methyltransferase (PNMT) in vitro. The choice of substituents on the 7-phenyl group of the sulfonanilides was based on the Topliss approach to structure-activity relationship studies. Information about the importance of an acidic hydrogen atom on the sulfonamide nitrogen atom was obtained from the preparation and testing of a tertiary N-methylsulfonanilide (15). Other THIQ's (1,2,3,4-tetrahydroisoquinolines) containing sulfur substituents in the 7 position were prepared and tested and consisted of 7-N-benzyl and 7-N-phenethyl derivatives of SK&F 29661 (16-18) and 7-(phenacylthio)-and 7-(phenacylsulfonyl)-THIQ (19 and 20). The two most potent inhibitors were the 7-p-bromo- and -chlorosulfonanilides, 2 and 6. However, neither was an effective inhibitor of norepinephrine to epinephrine conversion when tested in an in vivo mouse assay at unit doses of 25 or 100 mg/kg.


Asunto(s)
Epinefrina/biosíntesis , Isoquinolinas/síntesis química , Feniletanolamina N-Metiltransferasa/antagonistas & inhibidores , Glándulas Suprarrenales/efectos de los fármacos , Glándulas Suprarrenales/metabolismo , Anilidas/síntesis química , Animales , Técnicas In Vitro , Isoquinolinas/farmacología , Masculino , Ratones , Norepinefrina/metabolismo , Conejos , Relación Estructura-Actividad , Sulfonamidas/síntesis química
14.
J Med Chem ; 22(7): 840-4, 1979 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-448683

RESUMEN

The potent hypoglycemic activity of 3-(3-methyl-2-pyridyl)propan-1-ol (1) prompted us to synthesize and study related structures. Some of the variables studied were the position of the methyl and alcohol side chains, the distance between the heterocyclic ring and the hydroxyl group, the effect of additional nuclear substitution, and the effects of branching and substitution on the alcohol side chain. The compounds were tested in 48-h fasted rats, usually at a dose of 150 mg/kg po. 1, the corresponding propionic acid 12, the acetate and methyl ether of 1 (22 and 23), and the 5-methyl analogue of 1 (29) were of comparable hypoglycemic potency. However, these compounds all caused a concomitant elevation of hepatic triglycerides and/or death in the test animals when observations were continued for 4--24 h.


Asunto(s)
Hipoglucemiantes/síntesis química , Piridinas/síntesis química , Alcoholes/síntesis química , Alcoholes/farmacología , Animales , Técnicas In Vitro , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Piridinas/farmacología , Ratas , Relación Estructura-Actividad , Triglicéridos/metabolismo
15.
J Med Chem ; 21(5): 489-92, 1978 May.
Artículo en Inglés | MEDLINE | ID: mdl-660598

RESUMEN

A series of substituted 2-arylthiazolo[3,2-a]pyridinium salts (1a-q) was prepared by known methods and tested for hypoglycemic activity in 48-h fasted rats. Two compounds, 2-phenylthiazolo- and 8-methyl-2-phenythiazolo[3,2-a]pyridinium perchlorate (1a and 1q), showed consistent hypoglycemic activity in this screen, demonstrating that a high degree of structural specificity was required for hypoglycemic activity. At higher doses the hypoglycemic activity of 1a and 1q was associated with elevated levels of hepatic triglycerides.


Asunto(s)
Hipoglucemiantes/síntesis química , Compuestos de Piridinio/síntesis química , Animales , Técnicas In Vitro , Masculino , Métodos , Compuestos de Piridinio/farmacología , Ratas , Relación Estructura-Actividad
16.
J Med Chem ; 20(4): 572-6, 1977 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-850242

RESUMEN

3-Mercaptopicolinic acid (3-MPA), a potent hypoglycemic agent in fasted rats, provided the impetus for substituting this compound with a 5-mercapto group (1), a 6-carboxyl group (2), and a 5-mercapto and 6-carboxyl group (3) and for replacing the pyridine ring with other heterocycles: quinoline (4), thiazole (5), pyrazine (6), isoquinoline (7), and indole (8). The methyl sulfoxide (9) and sulfone (10) of 3-MPA were also prepared. The new compounds 1-10, with the exception of 8, did not lower blood glucose levels in 48-h fasted rats. 8 was toxic at doses which were hypoglycemic.


Asunto(s)
Ácidos Picolínicos/síntesis química , Compuestos de Sulfhidrilo/síntesis química , Animales , Hipoglucemiantes/síntesis química , Masculino , Métodos , Ácidos Picolínicos/farmacología , Ratas , Relación Estructura-Actividad , Compuestos de Sulfhidrilo/farmacología
17.
J Med Chem ; 18(9): 952-4, 1975 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1159720

RESUMEN

Phenacyl-riphenylphosphorane (1a) and several analogs substituted in the meta position of the phenacyl group lowered blood glucose levels in 48-hr fasted rats. The corresponding phosphonium salts had comparable hypoglycemic activity. Two compounds (1a and 1b) were also hypoglycemic in fed rats, but hypoglycemia could not be elicited in another species.


Asunto(s)
Hipoglucemiantes/síntesis química , Fosforanos/síntesis química , Animales , Glucemia/análisis , Depresión Química , Masculino , Compuestos Onio/síntesis química , Compuestos Onio/farmacología , Fosforanos/farmacología , Ratas , Relación Estructura-Actividad
18.
J Med Chem ; 20(4): 577-9, 1977 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15114

RESUMEN

A series of S-alkanoyl and benzoyl derivatives of 3-mercaptopicolinic acid (3-MPA) was prepared and studied for hypoglycemic activity. Three alkanoyl derivatives (propionyl, pivaloyl, and 1-adamantanecarbonyl, 19-21) were prepared with increasing bulk around the thio ester bond. The benzoyl derivatives contained aromatic substituents chosen from a sigma-pi cluster chart so that the esters prepared had a wide range of electronic and solubility properties. In general, compounds with substituents which increased lipid solubility [p-chlorobenzoyl (4), p-trifluoromethylbenzoyl (6), and pivaloyl (20)] had the greatest potency at a dose of 300 mg/kg. Hydrolysis rates, measured at pH 6 and 8, indicated that in vivo breakdown to 3-MPA probably did not account for the observed hypoglycemic activity of the esters. 4, 6, and 20 were less potent than 3-MPA in comparative dose range studies.


Asunto(s)
Hipoglucemiantes/síntesis química , Ácidos Picolínicos/síntesis química , Acilación , Animales , Concentración de Iones de Hidrógeno , Hidrólisis , Masculino , Métodos , Ácidos Picolínicos/análisis , Ácidos Picolínicos/farmacología , Ratas
19.
J Med Chem ; 20(12): 1572-7, 1977 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-592321

RESUMEN

3-Mercapto-4-methylpicolinic acid one of very few compounds derived from 3-mercaptopicolinic acid (3-MPA) to have hypoglycemic activity. In an effort to find compounds with greater potency than 3-MPA, several 4-substituted 3-mercaptopicolinic acids (4-OMe, OC6H5, SMe, SH, Cl, NH2, Et; 1-7) were prepared and tested in 48-h fasted rats. None was hypoglycemic in this test system after oral dosing of 150 mg/kg.


Asunto(s)
Hipoglucemiantes/síntesis química , Ácidos Picolínicos/síntesis química , Animales , Masculino , Ácidos Picolínicos/farmacología , Ratas , Relación Estructura-Actividad , Compuestos de Sulfhidrilo/síntesis química , Compuestos de Sulfhidrilo/farmacología
20.
Neuroscience ; 31(2): 327-45, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2797439

RESUMEN

In this study the distribution of the cholinergic neurons was examined in relation to the compartmental organization of nucleus accumbens. This was accomplished by charting the location of the choline acetyltransferase-immunoreactive neurons and mapping their distribution in relation to cytoarchitectural features and the patterns of acetylcholinesterase activity and enkephalin immunoreactivity. Choline acetyltransferase-containing perikarya are inhomogeneously distributed in nucleus accumbens. Their density is lowest at the rostral pole and highest, caudomedially, at the septal pole. The cells form a compact, medial column and a diffuse, lateral zone and, moreover, there are distinct gradients in their distribution. The highest numbers of immunoreactive perikarya occur within the intensely immunostained zones of choline acetyltransferase-immunoreactive neuropil in ventral and ventromedial parts of the nucleus, whereas lower numbers coincide with choline acetyltransferase-poor zones in the central part of the nucleus. Zones of intensely choline acetyltransferase-immunoreactive neuropil are largely in register with regions of high acetylcholinesterase activity in middle and caudal parts of the nucleus but do not coincide rostrally. Choline acetyltransferase-rich zones correspond to moderate enkephalin immunoreactivity in the outer shell of the nucleus, but a moderately choline acetyltransferase-immunostained matrix surrounds "patches" of intense enkephalin immunoreactivity in the core. Small aggregates of cells, which feature commonly in nucleus accumbens, seem to be avoided by both choline acetyltransferase- and enkephalin-immunoreactive zones. Choline acetyltransferase-immunoreactive processes are mostly confined by the boundaries of their respective immunoreactive zones. Few choline acetyltransferase-immunoreactive neurons lie in the enkephalin-rich patches and those that lie close to the patches show little preference in the directionality of their processes such that some cross the borders, whereas others do not. Thus, our findings show that the cholinergic elements are differentially distributed within nucleus accumbens; that these elements are compartmentally ordered; and that, in light of their limited access to other compartments, they possibly play only a minor role in intercompartmental communication.


Asunto(s)
Colina O-Acetiltransferasa/metabolismo , Fibras Colinérgicas/enzimología , Núcleo Accumbens/citología , Animales , Femenino , Inmunohistoquímica , Ratas , Ratas Endogámicas , Núcleos Septales
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