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1.
Nature ; 520(7546): 209-11, 2015 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-25855457

RESUMO

The chemical properties of an element are primarily governed by the configuration of electrons in the valence shell. Relativistic effects influence the electronic structure of heavy elements in the sixth row of the periodic table, and these effects increase dramatically in the seventh row--including the actinides--even affecting ground-state configurations. Atomic s and p1/2 orbitals are stabilized by relativistic effects, whereas p3/2, d and f orbitals are destabilized, so that ground-state configurations of heavy elements may differ from those of lighter elements in the same group. The first ionization potential (IP1) is a measure of the energy required to remove one valence electron from a neutral atom, and is an atomic property that reflects the outermost electronic configuration. Precise and accurate experimental determination of IP1 gives information on the binding energy of valence electrons, and also, therefore, on the degree of relativistic stabilization. However, such measurements are hampered by the difficulty in obtaining the heaviest elements on scales of more than one atom at a time. Here we report that the experimentally obtained IP1 of the heaviest actinide, lawrencium (Lr, atomic number 103), is 4.96(+0.08)(-0.07) electronvolts. The IP1 of Lr was measured with (256)Lr (half-life 27 seconds) using an efficient surface ion-source and a radioisotope detection system coupled to a mass separator. The measured IP1 is in excellent agreement with the value of 4.963(15) electronvolts predicted here by state-of-the-art relativistic calculations. The present work provides a reliable benchmark for theoretical calculations and also opens the way for IP1 measurements of superheavy elements (that is, transactinides) on an atom-at-a-time scale.

2.
Energy Fuels ; 38(11): 10038-10049, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38863685

RESUMO

A systematic study on the electrochemical reforming of monosaccharides (fructose, glucose, and xylose) using Pt-based anodic electrocatalysts is here presented for the first time to completely optimize the anodic catalyst and electrolyzer operating conditions. First, the electro-oxidation of each molecule was studied using a monometallic (Pt) and two bimetallic (PtNi and PtCo) anodic electrocatalysts supported on graphene nanoplatelets (GNPs). Tests in a three-electrode cell showed superior electrochemical activity and durability of PtNi/GNPs, especially at potentials higher than 1.2 V vs RHE, with the highest electrocatalytic activity in d-xylose electro-oxidation. Then, monometallic (Pt and Ni) and bimetallic electrocatalysts with different Pt:Ni mass ratios (1:1 and 2:1) were studied for d-xylose electro-oxidation, with the 2:1 mass ratio presenting the best results. This electrocatalyst was selected as the most suitable for scale-up to an anion-exchange membrane electrolyzer, where the optimal operating potential was determined. Additionally, stable operating conditions of the electrolyzer were achieved by cyclic H2 production and cathodic regeneration polarization steps. This led to suitable and reproducible H2 production rates throughout the production cycles for renewable hydrogen production from biomass-derived streams.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38768852

RESUMO

OBJECTIVE: To carry out a methodologically complete validation of the Spanish version of the Keratoconus End-Points Assessment Questionnaire (KEPAQ) in a Spanish population with keratoconus. METHODS: Analytical, prospective study, including patients with keratoconus without previous surgical history, in which a measurement of quality of life was performed using the KEPAQ questionnaire, a complete exploration of the anterior pole and a corneal elevation topography with the Galilei G6 topographer. The evaluation of the psychometric characteristics of the scale in the studied population was carried out using Rasch modeling. RESULTS: A total of 140 patients with keratoconus were included, with a median age of 26.0 years, the majority (57.6%) being men. For the KEPAQ-E subscale, the median score was 69.3, with a reliability of 0.85 and an eigenvalue of the first contrast of 2.34. For the KEPAQ-F, the median score was 56.4, with a reliability of 0.88 and an eigenvalue of 2.00. All infit and outfit parameters were within normal limits for both subscales. A significant evaluation was found between the evaluations of both subscales (rho = 0.696; p < 0.001). The evaluations of the subscales and various clinical and tomographic characteristics showed a significant classification between them (p value between 0.048 y 0.001). CONCLUSION: The KEPAQ is a psychometrically robust and valid scale to evaluate quality of life in the Spanish population with keratoconus. This questionnaire can be easily used for both clinical and research aims.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38972352

RESUMO

INTRODUCTION: Implantable pulse generator (IPG) is a neurostimulation therapy mediated by electrodes and surgically implanted in a subcutaneous "pocket" used for the control of numerous pathologies. This study examines both the prevalence of pain associated with IPG implantation ("pain pocket syndrome") and its associated characteristics. MATERIALS AND METHODS: 56 patients with an IPG were included in the study. A health questionnaire was conducted to determine the presence of pain associated with the pocket and its neuropathic characteristics, as well as associated aesthetic concerns, location, situations that accentuate or alleviate pain, medications used for baseline and pocket pain control and other factors associated. RESULTS: Pain in the area of implantation of the IPG had a prevalence of 52.6% of patients (n = 27), in our sample, with a mean score on the visual analogic scale (VAS) of 4.9 points [3.9-5.8 points], with neuropathic characteristics in 53.3% (n = 16) of the patients with pain, with differences between the mean VAS score of the female (5.5 [4.3-5.8 points]) and males (3.5 points [2.1-4.9 points]) (p = 0.04). CONCLUSION: Pocket pain is a condition with a higher prevalence than described in previous studies, being of a higher intensity in females, involving a moderate pain in the area of implantation of the neuromodulating therapy. This pain has neuropathic characteristics and could require a repositioning intervention. Hence, more studies in this field should be carried to detect and prevent this syndrome.

5.
Radiologia ; 55(2): 142-7, 2013.
Artigo em Espanhol | MEDLINE | ID: mdl-22015223

RESUMO

OBJECTIVE: To determine whether the introduction of digital mammography in breast cancer screening has resulted in changes in the detection and management of microcalcifications. MATERIAL AND METHODS: We retrospectively studied the performance indicators of our breast cancer screening program that are related to the diagnosis of microcalcifications (rates of recall and recommendation of intermediate follow-up after screening, rate of indication of invasive procedures for microcalcifications and their positive predictive value, detection rate for microcalcifications, and number of ductal carcinomas in situ (DCIS) diagnosed). We compared the results obtained using direct digital mammography (september 2008-august 2009) with those obtained using analog mammography (September 2006-August 2007). STATISTICAL ANALYSIS: Chi-square test and measures of association. RESULTS: We found that using digital mammography led to significant increases in the recall rate (from 50.8 to 64‰), in the rate of intermediate follow-up after screening (from 9.41 to 18.7‰), in the rate of indication for invasive procedures (from 1.88 to 3.01‰), in the cancers detected through microcalcifications (from 0.86 to 1.36‰), and in the number of DCIS diagnosed. CONCLUSION: Direct digital mammography has improved the detection of microcalcifications, increasing the number of DCIS diagnosed without decreasing the positive predictive value of the invasive procedures indicated for microcalcifications. However, direct digital mammography has had a negative effect by increasing the recall rate and indication for short-term follow-up, possibly due to the difficulty of comparing the findings with those of earlier analog mammograms.


Assuntos
Doenças Mamárias/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Detecção Precoce de Câncer , Mamografia/métodos , Intensificação de Imagem Radiográfica , Doenças Mamárias/terapia , Neoplasias da Mama/complicações , Calcinose/complicações , Calcinose/terapia , Carcinoma Intraductal não Infiltrante/complicações , Feminino , Humanos , Estudos Retrospectivos
6.
Heliyon ; 9(10): e20748, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37876428

RESUMO

In this work, metal-free boron-doped graphene-based aerogels were successfully synthesized via a one-step autoclave assembly followed by freeze-drying and used as electrocatalysts for the hydrogen evolution reaction (HER) in acidic media. The synthesized reduced graphene oxide aerogels (rGOA) showed improved electrocatalytic activity by introducing boron and structural defects. The amount of boric acid used both as a dopant and reducing agent in the synthesis was optimized (boric acid/GO mass ratio = 17.5) to practically reach the crystallization limit of boric acid (boric acid/GO mass ratio = 20). It was observed that the higher the amount of boric acid added, the more boron was incorporated into the carbonaceous structure, improving the electrocatalytic activity of the final aerogel. Furthermore, calcination of the boron-doped electrocatalyst at 600 °C resulted in final aerogels with low oxygen content, moderate surface area, bimodal pore size distribution, and a high electrochemical active surface area. The final 3D graphene aerogel developed in this work, showed such outstanding electrocatalytic activity in HER as to replace noble metal-based electrocatalysts in the future.

7.
Appl Radiat Isot ; 200: 110913, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37442027

RESUMO

This paper describes a procedure for the validation of alpha-particle sources (exempt unsealed sources) to be used in experimental setups with liquefied gases at cryogenic temperatures (down to -196 °C) and high vacuum. These setups are of interest for the development and characterization of neutrino and dark matter detectors based on liquid argon, among others. Due to the high purity requirements, the sources have to withstand high vacuum and cryogenic temperatures for extended periods. The validation procedure has been applied to 241Am sources produced by electrodeposition.

8.
J Electr Bioimpedance ; 12(1): 3-10, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34413917

RESUMO

A portable electrical impedance spectroscopy device was developed to monitor the bioimpedance resistive component of bovine meat by injecting a sinusoidal current of 1 mA at 65 kHz. Both right and left longissimus dorsi muscles were trimmed from 4 slaughtered cows. The left muscle portions were frozen to -18 °C for 7 days while the right ones were meantime maintained at 5 °C. Mean value of impedance per length (Ω/cm) of frozen and thawed left samples was 31% lower than that of right non-frozen one (P = 0.0001). It was concluded that the device is reliable for monitoring the maturation of beef meat in situ with the possibility of revealing undeclared freeze-thaw cycles.

9.
Rev Sci Instrum ; 79(2 Pt 2): 02A906, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18315161

RESUMO

The KEKCB is an electron cyclotron resonance (ECR) ion source for converting singly charged ions to multicharged ones at Tokai Radioactive Ion Accelerator Complex. By using the KEKCB, singly charged gaseous and nongaseous ions were converted to multicharged ones of A/q approximately 7 with efficiencies of 7% and 2%, respectively. The conversion efficiency was found to be independent of the lifetime of the radioactive nuclei having lifetimes of the order of one second. Three collimators located at the entrance and the exit of the KEKCB defined the beam axis and facilitated beam injection. Grinding and washing the surfaces of aluminum electrode and plasma chamber dramatically reduced impurities originating from the ECR plasma of the KEKCB.

10.
J Thromb Haemost ; 4(7): 1530-6, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16839350

RESUMO

BACKGROUND: Cardiovascular risk factors for myocardial infarction (MI) are less frequent in younger than in older MI survivors. Therefore, the thrombotic component of MI may play a more important role at a young age. As activated protein C (APC) provides systemic anticoagulant and anti-inflammatory protection, a low plasma APC level may be an arterial thrombotic risk factor. AIM: To determine whether there is an association between reduced APC levels and early MI and severe coronary lesions. METHODS: APC was measured in 231 young MI survivors and 231 controls. RESULTS: Low APC levels were significantly associated with MI. Compared with the fourth quartile, the odds ratio (OR) for APC values in the first quartile was 3.7 [95% confidence interval (CI) = 2.1-6.4], and 3.2 (1.5-7.0) after adjustment for cardiovascular risk factors. Moreover, each decrease of 0.43 ng mL(-1) (1 SD) in APC increased the OR 1.7 times (1.4-2.2), and 1.5 times (1.2-1.9) after adjustment for cardiovascular risk factors. Low APC levels were also associated with the number of coronary arteries affected and with the severity of coronary lesions (P < 0.001). CONCLUSIONS: There is a significant association between low circulating APC levels and both early MI and the extent and severity of coronary atherosclerosis, which might be related to the anticoagulant and anti-inflammatory properties of APC.


Assuntos
Doença da Artéria Coronariana/patologia , Infarto do Miocárdio/sangue , Proteína C/análise , Sobreviventes , Adulto , Fatores Etários , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco , Índice de Gravidade de Doença
11.
Transplant Proc ; 38(8): 2575-6, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17098007

RESUMO

AIM: To undertake an evolutionary analysis of echocardiographic examinations carried out during follow-up of cardiac transplant patients. MATERIALS AND METHODS: The study included 193 consecutive patients transplanted between August 1998 and December 2004. We excluded pediatric, cardiopulmonary, and repeat transplants. Four echocardiographic examinations were analyzed per patient (first, second, third quarter and the last study carried out; average time from transplant: 1115 +/- 681 days). The total number of examinations was 772. The evaluated variables were thickness of walls and diameters of the cavities, systolic and diastolic functions, pericardial effusion, and number of rejections. RESULTS: The isovolumetric relaxation time showed reduced values during early echocardiography with subsequent increases during evolution (first echocardiogram: 92 +/- 16 vs final echocardiogram 101 +/- 16 ms; P < .0001). Right ventricular function showed initial deterioration with subsequent recovery (first echocardiogram: 16% vs final echocardiogram: 8%; P < .05); moreover, the existence of delayed malfunction of the right ventricle was correlated with a higher incidence of transplant rejection (P < .01). Pericardial effusion was initially present with a tendency to reduce over time (first echocardiogram: 58% vs final echocardiogram: 12%; P < .0001). There was no difference in the other variables. CONCLUSIONS: Cardiac transplant patients undergo evolutionary echocardiogram alterations that were mainly early and normalized as of the first quarter. The most usual changes in this period were restrictive isovolumetric behavior accompanied by some degree of depressed right ventricular function. Right ventricular malfunction during late evolution was correlated with a higher incidence of transplant rejection during follow-up.


Assuntos
Eletrocardiografia , Transplante de Coração/fisiologia , Rejeição de Enxerto/diagnóstico por imagem , Seleção de Pacientes , Pericárdio/diagnóstico por imagem , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Ultrassonografia , Vasodilatação
12.
Transplant Proc ; 38(8): 2534-6, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17097992

RESUMO

BACKGROUND: Brain naturietic peptide (BNP) elevations have been reported in heart transplant patients both at baseline and during rejection. An association between BNP levels and certain echocardiographic and hemodynamic abnormalities has also been found in nontransplanted heart disease patients. We sought to determine whether BNP values were correlated with echocardiographic and hemodynamic parameters among a large cohort of heart transplant patients. MATERIALS AND METHODS: We studied 71 consecutive heart transplant patients, excluding combined grafts, retransplants, and pediatric cases. We performed 488 BNP determinations during catheterization and within 48 hours of echocardiography. Hemodynamic parameters included mean pulmonary artery pressure, right ventricular systolic and diastolic pressures. Doppler echocardiography parameters were wall thickness, ventricular mass, left and right ventricular end-diastolic and end-systolic diameters, isovolumic relaxation time, and mitral flow deceleration time. RESULTS: We observed significant correlations between BNP values and left ventricular size, ventricular mass, and a restrictive filling pattern. BNP levels were also significantly correlated with right ventricular size, mean pulmonary artery pressure, and right ventricular diastolic and end-diastolic pressures. CONCLUSIONS: In heart transplant patients, BNP levels positively correlated with ventricular diameters and a restrictive filling pattern. An increase in right ventricle and pulmonary artery pressures was associated with elevated BNP values.


Assuntos
Pressão Sanguínea , Transplante de Coração/fisiologia , Peptídeo Natriurético Encefálico/sangue , Biomarcadores/sangue , Eletrocardiografia , Humanos , Seleção de Pacientes
13.
Appl Radiat Isot ; 64(7): 751-4, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16580839

RESUMO

The Cd concentration in food is a public concern related to the human health. In order to remove Cd-polluted food, the development and validation of a rapid and sensitive method of Cd analysis is required. By applying the multiple gamma-ray detection method to prompt gamma-ray analysis (PGA), the influence from nuclei which emit only one prompt gamma-ray at a time at every neutron capture reaction can be reduced, therefore the quantification limit of Cd is improved significantly. The limit of Cd contained in rice in the case of MPGA was evaluated, and under our proposed experimental conditions, it may be possible to quantify Cd content in rice to within 0.2 ppm in 10 min.


Assuntos
Cádmio/análise , Contaminação de Alimentos/análise , Oryza/química , Raios gama , Humanos , Análise Espectral/métodos
14.
Rev. Soc. Esp. Dolor ; 28(2): 100-110, Mar-Abr. 2021. graf, tab
Artigo em Inglês, Espanhol | IBECS (Espanha) | ID: ibc-227705

RESUMO

Las infiltraciones con toxina botulínica han sido utilizadas en el tratamiento del dolor asociado a múltiples patologías, como distonías focales, espasticidad, cefaleas y dolor miofascial. Sin embargo, los resultados de los diferentes estudios realizados con toxina botulínica en el síndrome de dolor miofascial (SDM) son contradictorios. El objetivo de la presente revisión es analizar la evidencia de la eficacia de la toxina botulínica tipo A (TBA) frente a placebo en la disminución del dolor crónico de origen miofascial.Se realizó una búsqueda bibliográfica en PubMed, Web of Science (WoS), Scielo y Scopus, utilizando las siguientes palabras clave: dolor miofascial, punto gatillo, toxina botulínica y bótox. Los estudios que cumplieron los criterios inclusión fueron once ensayos clínicos que comparaban la TBA frente a solución salina normal (SSN).Aunque en la mayoría de los ensayos clínicos ana­lizados no podemos evidenciar un beneficio de la TBA frente a SSN, no sería acertado concluir que la toxina botulínica no está indicada en el tratamiento de dolor asociado al SDM, dado que existe una selección de pacien­tes muy heterogénea, hay una gran variabilidad en la dosis de toxina botulínica, se usan diferentes técnicas de infiltración de los puntos gatillo (PG), la duración de los estudios es variable y no hay estudios que realicen un análisis costo-efectivo.Se necesitan ensayos clínicos más específicos, con muestras más homogéneas, que nos permitan sacar conclusiones acerca del papel de la TBA en el tratamiento del SDM.(AU)


Botulinum toxin injections have been used in pain treatment associated with pathologies such as focal dystonia, spasticity, headaches and myofascial pain. However, results from botulinum toxin trials in myofascial pain syndrome (MPS) are contradictory.The objective of this paper is to analyze the evidence of botulinum toxin type A (BTA) efficacy compared to placebo in myofascial pain management. Literature search was performed in PubMed, Web of Science (WoS), Scielo and Scopus, using the following key words: myofascial pain, trigger point, botulinum toxin and botox. Eleven clinical trials comparing BTA versus normal saline solution (NSS) met the inclusion criteria. Although most of the clinical trials analyzed cannot demonstrate a BTA superiority, it would not be correct to conclude that botulinum toxin is not indicated in miofascial pain treatment due to the great heterogeneous patient selection, variability in BTA doses, different trigger points (TP) injections techniques, variability in trials duration, and absence of cost-effective analysis.More specific clinical trials are required using homogeneous samples to provide conclusive evidence for BTA in the MPS treatment.(AU)


Assuntos
Humanos , Masculino , Feminino , Manejo da Dor/métodos , Toxinas Botulínicas Tipo A/uso terapêutico , Síndromes da Dor Miofascial/tratamento farmacológico , Dor Crônica/tratamento farmacológico , Resultado do Tratamento , Manejo da Dor/tendências
15.
Transplant Proc ; 37(9): 4011-3, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16386612

RESUMO

BACKGROUND: Certain cardiovascular risk factors have been linked to morbidity and mortality in heart transplant (HT) patients. The sum of various risk factors may have a large cumulative negative effect, leading to a substantially worse prognosis and the need to consider whether HT is contraindicated. The objective of this study was to determine whether the risk factors usually available prior to HT result in an excess mortality in our setting that contraindicates transplantation. MATERIALS AND METHODS: Consecutive patients who underwent heart transplantation from November 1987 to January 2004 were included. Heart-lung transplants, retransplants, and pediatric transplants were excluded. Of the 384 patients, 89% were men. Mean age was 52 years (range, 12 to 67). Underlying disease included ischemic heart disease (52%), idiopathic dilated cardiomyopathy (36%), valvular disease (8%), and other (4%). Variables considered risk factors were obesity (BMI >25), dyslipidemia, hypertension, prior thoracic surgery, diabetes, and history of ischemic heart disease. Survival curves by number of risk factors using Kaplan-Meier and log-rank for comparison of curves. RESULTS: Overall patient survival at 1, 5, 10, and 13 years was 76%, 68%, 54%, and 47%, respectively. Survival at 10 years, if fewer than two risk factors were present, was 69%; 59% if two or three factors were present; and 37% if more than three associated risk factors were present (P = .04). CONCLUSIONS: The presence of certain risk factors in patients undergoing HT resulted in lower survival rates. The combination of various risk factors clearly worsened outcomes. However, we do not believe this should be an absolute contraindication for transplantation.


Assuntos
Transplante de Coração/mortalidade , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade , Obesidade/epidemiologia , Seleção de Pacientes , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Espanha , Taxa de Sobrevida , Fatores de Tempo
16.
Transplant Proc ; 37(9): 4024-7, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16386616

RESUMO

BACKGROUND AND AIMS: Immunosuppressive therapy has undergone great changes in recent years as a result of the introduction of new drugs, presumed a prior to be more effective and better tolerated. The greatest advance seems to have been the introduction of interleukin-2 (IL-2) receptor antagonists. The objective of this study was to determine whether the use of IL-2 receptor antagonists in induction therapy has implications for the development of rejection and survival. MATERIALS AND METHODS: Three hundred sixty-five consecutive cardiac transplant patients who received induction therapy were included. Heart-lung and transplants in children under 10 years were excluded. Three groups were compared according to the induction therapy (OKT3, 10 days; OKT3, 7 days; and IL-2R antagonists). Each treatment corresponded to a time period: OKT3 10 days from June 1989 to April 1994; OKT3 7 days from May 1994 to October 2002; and IL-2R antagonists from November 2002 to May 2004. Baseline characteristics of recipient and donor, surgical times, postsurgical complications, maintenance immunosuppression, number of rejections, time (days) to first rejection, and probability of survival at 1 year were recorded. We used analysis of variance, chi(2) test, Kaplan-Meier curves, and log-rank test as appropriate. A P-value < .05 was considered significant. RESULTS: There were significant differences in the characteristics of the transplanted patients in the various time periods. Thus, recipients in the OKT3 10 day group had worse status but better donors, whereas recipients in the IL-2R antagonists group had better status but older donors with longer duration of ischemia. The incidence of acute graft failure was similar in the three groups. The number of rejection episodes in the first year was higher among the OKT3 groups (OKT3 10 days, 1.7 +/- 1.3; OKT3 7 days, 1.2 +/- 1.2; IL-2R antagonists, 1.0 +/- 1.2; P = .02) and the probability of survival at 1 year was also lower (OKT3 10 days, 74%; OKT3 7 days, 77%; IL-2R antagonists, 94%; P = .0007). CONCLUSIONS: Induction therapy with IL-2 antagonists offers important advantages over treatment with OKT3 in terms of survival, with absolute and relative risk reductions of 20% and 27%. Furthermore, it did not increase the number of rejections, although this may have been due to the greater use of MMF versus azathioprine.


Assuntos
Rejeição de Enxerto/epidemiologia , Transplante de Coração/imunologia , Imunossupressores/uso terapêutico , Adolescente , Adulto , Idoso , Criança , Esquema de Medicação , Feminino , Transplante de Coração/mortalidade , Humanos , Imunossupressores/efeitos adversos , Masculino , Pessoa de Meia-Idade , Muromonab-CD3/uso terapêutico , Probabilidade , Análise de Sobrevida , Sobreviventes
17.
Transplant Proc ; 37(9): 4064-6, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16386627

RESUMO

INTRODUCTION: It is known that there is a high incidence of diabetes mellitus (DM) among heart transplant (HT) patients, which may be up to 30% at 5 years. The presence of DM has been associated with increased morbidity (infections, renal dysfunction, or graft vascular disease), and its development has been related primarily to immunosuppressive therapy. The objective of this study was to determine, in our experience, the presence of predictive variables for the development of DM following HT. METHODS: We studied 315 consecutive non-DM patients (88.6% men, mean age 51.5 years) who underwent HT in our hospital from November 1987 to May 2003, analyzing all variables that could be related to the development of DM during follow-up. Student t-test and chi(2) test were used for univariate statistical analysis and logistic regression for multivariate analysis. RESULTS: Of the 315 patients, 64 developed DM (20.3%) during a mean follow-up of 3.3 years. The univariate analysis showed that patients developing DM are older (54.9 +/- 8.7 versus 50.7 +/- 11.8 years, P = .008), have a higher body mass index (BMI) (27.3 +/- 3.8 versus 25.7 +/- 3.7, P = .003), a higher prevalence of HT (37.5% versus 23.5%, P = .023), a lower frequency of urgent HT (9.4% versus 26.2%, P = .004), are more often treated with steroids (85.9% versus 70.1%, P = .011) and tacrolimus (12.5% versus 4.4%, P = .015), and have a higher frequency of rejection episodes (71.2% versus 44.6%, P = .001). Multivariate analysis identified the following as predictive factors for the development of DM: age (OR = 1.04, P = .013), urgent HT (OR = 0.36, P = .031), treatment with tacrolimus (OR = 3.89, P = .012), and number of rejections (OR = 2.34, P = .002). CONCLUSION: In our population, age, urgent HT (which had a protective effect), treatment with tacrolimus, and number of rejections were independent predictive variables for the development of DM during follow-up.


Assuntos
Diabetes Mellitus/epidemiologia , Transplante de Coração/efeitos adversos , Adulto , Análise de Variância , Índice de Massa Corporal , Feminino , Seguimentos , Rejeição de Enxerto/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Fatores de Risco , Fatores de Tempo
18.
FEBS Lett ; 184(2): 193-6, 1985 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-3922786

RESUMO

The reaction of porcine pancreatic lipase with an organophosphorus compound bis-p-nitrophenyl methylphosphonate (BNMP) resulted in the complete and irreversible inhibition of lipase activity on tributyrin emulsion (25 degrees C, pH 7.5, 40 mM Na-veronal-HCl buffer) whereas the activity of the enzyme on p-nitrophenyl acetate solution remained unchanged. The BNMP-modified enzyme did not bind on hydrophobic interfaces (siliconized glass beads). Tyr 49 was presumed to be the modification site, and the conclusion has been made that this residue is implicated in the interface recognition site of pancreatic lipase.


Assuntos
Lipase/antagonistas & inibidores , Compostos Organofosforados/farmacologia , Animais , Sítios de Ligação , Cinética , Pâncreas/enzimologia , Serina/antagonistas & inibidores , Suínos , Tirosina/antagonistas & inibidores
19.
J Heart Lung Transplant ; 16(4): 454-9, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9154957

RESUMO

PURPOSE: The purpose of this study was to determine whether the angiotensin-converting enzyme inhibitor, fosinopril, has an antihypertensive effect in patients undergoing heart transplantation (HT), as well as any action on lipid levels (total cholesterol and its fractions, triglycerides and lipoprotein[a] [Lp(a)]). METHODS: The study included 15 male patients aged 54 +/- 10 years; nine had undergone transplantation as a result of ischemic heart disease and six as a result of idiopathic dilated cardiomyopathy. The average time from the heart transplantation was 12 +/- 4 months. Six transplantations were performed after antidiabetic treatment, and six were performed with patients receiving a hypolipidemic agent. The subjects of the study were patients with mild to moderate hypertension who were receiving antihypertensive treatment; the antihypertensive medications were withdrawn during 7 days. Periodic blood pressure and basal analytic determinations were then carried out after 4 and 12 weeks of treatment and 7 days after withdrawal of the antihypertensive medications. RESULTS: Significant differences (p < 0.05) were found in the systolic blood pressure (SBP) and diastolic blood pressure (DBP) compared with the basal values (SBP 160 +/- 11 mm Hg; DBP 98 +/- 8 mm Hg), after 4 weeks of treatment (SBP 138 +/- 10 mm Hg; DBP 83 +/- 7 mm Hg), and after 12 weeks of treatment (SBP 137 +/- 12 mm Hg; DBP 84 +/- 9 mm Hg); these differences persisted 7 days after the drug was withdrawn (SBP 150 +/- 12 mm Hg; DBP 95 +/- 10 mm Hg). The total cholesterol, low-density lipoprotein (LDL) cholesterol, and Lp(a) dropped compared with the basal levels (total cholesterol 184 +/- 19, LDL cholesterol 123 +/- 13, Lp(a) 29 +/- 12), after 4 weeks (total cholesterol 172 +/- 21, LDL cholesterol 116 +/- 8, Lp(a) 26 +/- 8) and after 12 weeks (total cholesterol 169 +/- 20, LDL cholesterol 115 +/- 6, Lp(a) 25 +/- 8) of treatment, returning to basal values on withdrawal of the drug. CONCLUSIONS: Fosinopril is a useful drug for the treatment of the mild to moderate arterial hypertension of heart transplant recipients, in addition to being capable of reducing the serum levels of total cholesterol, LDL cholesterol, and Lp(a). It should therefore be considered a first-line antihypertensive agent with beneficial effects on the lipid profile.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Pressão Sanguínea/efeitos dos fármacos , Fosinopril/administração & dosagem , Transplante de Coração/fisiologia , Lipídeos/sangue , Adulto , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Pressão Sanguínea/fisiologia , Colesterol/sangue , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Fosinopril/efeitos adversos , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Lipoproteína(a)/sangue , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/fisiopatologia , Resultado do Tratamento , Triglicerídeos/sangue
20.
J Heart Lung Transplant ; 19(2): 207-14, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10703698

RESUMO

BACKGROUND: Currently studies conflict on the impact on mortality of right bundle branch block development after transplantation. Most studies conclude that right bundle branch block does not affect patient survival. However, no distinction is made between patients in whom right bundle branch block progresses and those in whom it remains unchanged during follow-up. The objective of this study is to assess clinical or survival differences between patients who develop right bundle branch block and those who do not, and also to analyze these differences depending on progression of this conduction abnormality. MATERIALS AND METHODS: Ninety-seven consecutive heart transplant recipients with more than 1 year's survival were analyzed. Twelve-lead standard ECGs were performed during the first week after transplantation, which allowed for classification of patients depending on the presence or absence of right bundle branch block. Subsequently, throughout the first year, 2 groups were identified, depending on increase of the conduction defect. The groups were compared and factors determining the presence of right bundle branch block and progression of the conduction defect were found. Survival curves for the conduction defect were also compared. RESULTS: Fifty percent of the patients developed right bundle branch block after transplantation; it was progressive in 10. Progressive right bundle branch block was related to greater renal dysfunction (odds ration [OR] = 10.8; confidence interval [CI] = 2-58; p = 0.006), a larger number of rejections (p = 0.01), and a greater death rate (OR = 12.8; CI = 2.5-64; p = 0.002). The presence of progressive right bundle branch block was an independent predictor of long-term mortality (OR = 27.9; CI = 4.2-186.3; p = 0.0006). CONCLUSIONS: The development of right bundle branch block after transplantation is related to intraoperative factors and to a greater number of rejections. The presence of this conduction disorder, particularly if it progresses during the first year, identifies a sub-group of patients with a poorer long-term prognosis.


Assuntos
Bloqueio de Ramo/mortalidade , Transplante de Coração/efeitos adversos , Adulto , Bloqueio de Ramo/etiologia , Progressão da Doença , Eletrocardiografia , Feminino , Rejeição de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Análise de Sobrevida
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