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1.
Nature ; 603(7899): 52-57, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35236977

RESUMO

All disc-accreting astrophysical objects produce powerful disc winds. In compact binaries containing neutron stars or black holes, accretion often takes place during violent outbursts. The main disc wind signatures during these eruptions are blue-shifted X-ray absorption lines, which are preferentially seen in disc-dominated 'soft states'1,2. By contrast, optical wind-formed lines have recently been detected in 'hard states', when a hot corona dominates the luminosity3. The relationship between these signatures is unknown, and no erupting system has as yet revealed wind-formed lines between the X-ray and optical bands, despite the many strong resonance transitions in this ultraviolet (UV) region4. Here we report that the transient neutron star binary Swift J1858.6-0814 exhibits wind-formed, blue-shifted absorption lines associated with C IV, N V and He II in time-resolved UV spectroscopy during a luminous hard state, which we interpret as a warm, moderately ionized outflow component in this state. Simultaneously observed optical lines also display transient blue-shifted absorption. Decomposing the UV data into constant and variable components, the blue-shifted absorption is associated with the former. This implies that the outflow is not associated with the luminous flares in the data. The joint presence of UV and optical wind features reveals a multi-phase and/or spatially stratified evaporative outflow from the outer disc5. This type of persistent mass loss across all accretion states has been predicted by radiation-hydrodynamic simulations6 and helps to explain the shorter-than-expected duration of outbursts7.

2.
Nature ; 534(7605): 75-8, 2016 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-27251277

RESUMO

Accretion of matter onto black holes is universally associated with strong radiative feedback and powerful outflows. In particular, black-hole transients have outflows whose properties are strongly coupled to those of the accretion flow. This includes X-ray winds of ionized material, expelled from the accretion disk encircling the black hole, and collimated radio jets. Very recently, a distinct optical variability pattern has been reported in the transient stellar-mass black hole V404 Cygni, and interpreted as disrupted mass flow into the inner regions of its large accretion disk. Here we report observations of a sustained outer accretion disk wind in V404 Cyg, which is unlike any seen hitherto. We find that the outflowing wind is neutral, has a large covering factor, expands at one per cent of the speed of light and triggers a nebular phase once accretion drops sharply and the ejecta become optically thin. The large expelled mass (>10(-8) solar masses) indicates that the outburst was prematurely ended when a sizeable fraction of the outer disk was depleted by the wind, detaching the inner regions from the rest of the disk. The luminous, but brief, accretion phases shown by transients with large accretion disks imply that this outflow is probably a fundamental ingredient in regulating mass accretion onto black holes.

3.
Nature ; 505(7483): 378-81, 2014 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-24429635

RESUMO

Stellar-mass black holes have all been discovered through X-ray emission, which arises from the accretion of gas from their binary companions (this gas is either stripped from low-mass stars or supplied as winds from massive ones). Binary evolution models also predict the existence of black holes accreting from the equatorial envelope of rapidly spinning Be-type stars (stars of the Be type are hot blue irregular variables showing characteristic spectral emission lines of hydrogen). Of the approximately 80 Be X-ray binaries known in the Galaxy, however, only pulsating neutron stars have been found as companions. A black hole was formally allowed as a solution for the companion to the Be star MWC 656 (ref. 5; also known as HD 215227), although that conclusion was based on a single radial velocity curve of the Be star, a mistaken spectral classification and rough estimates of the inclination angle. Here we report observations of an accretion disk line mirroring the orbit of MWC 656. This, together with an improved radial velocity curve of the Be star through fitting sharp Fe II profiles from the equatorial disk, and a refined Be classification (to that of a B1.5-B2 III star), indicates that a black hole of 3.8 to 6.9 solar masses orbits MWC 656, the candidate counterpart of the γ-ray source AGL J2241+4454 (refs 5, 6). The black hole is X-ray quiescent and fed by a radiatively inefficient accretion flow giving a luminosity less than 1.6 × 10(-7) times the Eddington luminosity. This implies that Be binaries with black-hole companions are difficult to detect in conventional X-ray surveys.

4.
ScientificWorldJournal ; 2012: 603034, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22649298

RESUMO

Tropospheric ozone levels around urban and suburban areas at Europe and North America had increased during 80's-90's, until the application of NO(x) reduction strategies. However, as it was expected, this ozone depletion was not proportional to the emissions reduction. On the other hand, rural ozone levels show different trends, with peaks reduction and average increments; this different evolution could be explained by either emission changes or climate variability in a region. In this work, trends of tropospheric ozone episodes at rural sites in the northwest of the Iberian Peninsula were analyzed and compared to others observed in different regions of the Atlantic European coast. Special interest was focused on the air quality sites characterization, in order to guarantee their rural character in terms of air quality. Both episodic local meteorological and air quality measurements along five years were considered, in order to study possible meteorological influences in ozone levels, different to other European Atlantic regions.


Assuntos
Ozônio , Poluentes Atmosféricos , Clima , Geografia , População Rural , Estações do Ano
5.
Rehabilitacion (Madr) ; 55(4): 273-281, 2021.
Artigo em Espanhol | MEDLINE | ID: mdl-33771381

RESUMO

INTRODUCTION: Equinus in children produces a pattern of unsteady gait and inefficient and inadequate positioning in the wheelchair. Treatment with a serial casting cycle maintains range of motion and facilitates the development of normal movement patterns. Its use in combination with botulinum toxin has proven benefits, but there is a lack of guidance on the optimal management protocol. OBJECTIVE: The aim of this study were to describe the characteristics of the population with equinus of diverse aetiology and to determine the effectiveness of treatment with serial casting. We also aimed to assess its use in conjunction with botulinum toxin in patients with spastic cerebral palsy. MATERIAL AND METHOD: This longitudinal retrospective study included a sample of 95 Achilles tendons of children attended in a children's rehabilitation clinic between 2012 and 2018, with ankle dorsal flexion less than 10°, treated by a cycle of serial casts with or without botulinum toxin. The variables analysed were sex, year when treatment started, age, BMI, diagnosis, previous and/or later treatment, spasticity (modified Ashworth), laterality, active and passive joint range of dorsal and plantar flexion along with R1 (Tardieu). Measurements were carried out with a mechanical inclinometer prior to the first, second and third cast, after the third cast and at 2, 8 and 14 months. The statistical analysis was performed with SPSS®. RESULTS: There was a statistically significant improvement of 10.02° between passive dorsal flexion prior to the first cast and after the third cast, which remained at 6.66° (P=.02) between the former and after 14 months. CONCLUSIONS: Serial casting is an effective method in the management of equinus of any aetiology and has a minimal complication rate.


Assuntos
Toxinas Botulínicas Tipo A , Fármacos Neuromusculares , Moldes Cirúrgicos , Criança , Humanos , Espasticidade Muscular , Estudos Retrospectivos
6.
Rehabilitacion (Madr) ; 55(3): 233-237, 2021.
Artigo em Espanhol | MEDLINE | ID: mdl-33248716

RESUMO

Os subtibiale is a low prevalence accessory bone of the ankle. This bone is located in the posterior colliculus of the tibial medial malleolus, both in paediatric and adult ages. It can cause pain, redness and/or swelling, which can lead to a mistaken diagnosis of avulsion fracture. Adequate anatomical knowledge is crucial. First, we present the case of a school-aged boy, seen at the outpatient clinic for a 2-month history of pain in both inner ankles after an injury. Second, we present the case of an adult patient with a 3-day history of right medial ankle pain, with no previous injury, evaluated at the Emergency Department. Accurate history-taking and physical examination are essential. The diagnosis is given by conventional radiology of both ankles, in antero-posterior and lateral load views. The initial treatment is conservative (splint or orthesis) to establish and maintain the function of the foot during loading activities. If there is no recovery after 6 months, surgical treatment can be considered.


Assuntos
Fraturas do Tornozelo , Ossos do Tarso , Adulto , Tornozelo/diagnóstico por imagem , Fraturas do Tornozelo/diagnóstico por imagem , Fraturas do Tornozelo/cirurgia , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/cirurgia , Artralgia/diagnóstico , Artralgia/etiologia , Criança , Humanos , Masculino
7.
Nanomaterials (Basel) ; 10(12)2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33255714

RESUMO

Pathogenic bacteria have the ability to develop antibiotic resistance mechanisms. Their action consists mainly in the production of bacterial enzymes that inactivate antibiotics or the appearance of modifications that prevent the arrival of the drug at the target point or the alteration of the target point itself, becoming a growing problem for health systems. Chitosan-gold nanoparticles (Cs-AuNPs) have been shown as effective bactericidal materials avoiding damage to human cells. In this work, Cs-AuNPs were synthesized using chitosan as the reducing agent, and a systematic analysis of the influence of the synthesis parameters on the size and zeta potential of the Cs-AuNPs and their UV-vis spectra was carried out. We used a simulation model to characterize the interaction of chitosan with bacterial membranes, using a symmetric charged bilayer and two different chitosan models with different degrees of the chitosan amine protonation as a function of pH, with the aim to elucidate the antibacterial mechanism involving the cell wall disruption. The Cs-AuNP antibacterial activity was evaluated to check the simulation model.

8.
Water Sci Technol ; 59(10): 2017-27, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19474497

RESUMO

This study offers a solution for reducing the environmental effect of wastewaters generated by the olive-oil industry. Olive-oil companies produce variable quantities of wastewaters, which require treatment for disposal or reuse. Today, regulations are becoming increasingly strict regarding the parameters measured in these effluents. In Spain, the resolution by the president of the Hydrographical Confederation of the Guadalquivir on water use 2004 set parameter limits as follows: pH = 6.0-9.0, total suspended solid = 500 mg/L; and COD and BOD(5) (20)=1,500 mg O(2)/L. For the year 2006, maximum values for COD and BOD(5) (20) were fixed at 1,000 mg O(2)/L. To solve this problem, a study has been made to derive irrigation water from the above-mentioned effluents through chemical oxidation based on the Fenton's process. This would be first step towards using a closed-circuit system in olive-oil mills to treat and reuse effluents.


Assuntos
Óleos de Plantas , Eliminação de Resíduos Líquidos/métodos , Cloretos , Compostos Férricos , Indústria Alimentícia , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Cinética , Minerais/análise , Testes de Neutralização , Azeite de Oliva , Oxirredução , Oxigênio/análise , Espanha , Temperatura
9.
J Phys Chem B ; 111(49): 13726-33, 2007 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-18004836

RESUMO

Understanding the structure and dynamics of phospholipid bilayers is of fundamental relevance in biophysics, biochemistry, and chemical physics. Lipid Langmuir monolayers are used as a model of lipid bilayers, because they are much more easily studied experimentally, although some authors question the validity of this model. With the aim of throwing light on this debate, we used molecular dynamics simulations to obtain an atomistic description of a membrane of dimyristoylphosphatidic acid under different surface pressures. Our results show that at low surface pressure the interdigitation between opposite lipids (that is, back-to-back interactions) controls the system structure. In this setting and due to the absence of this effect in the Langmuir monolayers, the behavior between these two systems differs considerably. However, when the surface pressure increases the lipid interdigitation diminishes and so monolayer and bilayer behavior converges. In this work, four computer simulations were carried out, subjecting the phospholipids to lateral pressures ranging from 0.17 to 40 mN/m. The phospholipids were studied in their charged state because this approach is closer to the experimental situation. Special attention was paid to validating our simulation results by comparison with available experimental data, therebeing in general excellent agreement between experimental and simulation data. In addition, the properties of the lipid/solution interface associated with the lipid barometric phase transition were studied.


Assuntos
Compostos de Anilina/química , Bicamadas Lipídicas , Modelos Teóricos , Água/química
10.
J Hazard Mater ; 141(3): 680-92, 2007 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-16963182

RESUMO

The heavy ceramic industry (building materials and refractory products manufacture) is an important source of pollutants to the environment. For this reason these industrial sub-sectors are included in prevention and control pollution policies, specifically those of the European Union. The IPPC Directive pays particular attention to the mineral industries, not least to the ceramic industry (epigraph 3.5, Annex I). In this paper, a methodology which is being applied to support IPPC installations and the competent administrative authority in Galicia (NW Spain) is presented. For that, the Galician heavy ceramic industry is analysed, as also are the ways to study the Best Available Techniques (BAT) with a view to establishing the emission limit values (ELV) for each specific case. Hence, a technological state of the art has been carried out for both sub-sectors, from the point of view of implementation of the IPPC in Galicia. Following this, the processes are described briefly and an analysis of the consumption and emission levels of the main pollutants is made. An inventory that includes the best environmental practices and the preventive and abatement candidate techniques as BAT was elaborated for both considered sub-sectors. An information data sheet for each candidate BAT is presented as a method to help both the industries and the competent authority to identify a candidate technique of the inventory as BAT. Three illustrative examples of the application of this procedure are presented for different emissions to environmental media for Galician installations.


Assuntos
Cerâmica , Poluição Ambiental/prevenção & controle , Meio Ambiente , Poluição Ambiental/legislação & jurisprudência , União Europeia , Regulamentação Governamental , Espanha
11.
Rev Neurol ; 64(10): 459-470, 2017 May 16.
Artigo em Espanhol | MEDLINE | ID: mdl-28497442

RESUMO

INTRODUCTION: Spasticity is a medical problem with a high incidence that significantly impact on the quality of life of patients and their families. AIM: To analyze and to answer different questions about the use of botulinum toxin type A (BTA) in our clinical practice. DEVELOPMENT: A group of experts in neurology develop a list of topics related with the use of BTA. Two big groups were considered: spasticity in adults and in children with cerebral palsy. A literature search at PubMed for English, French, and Spanish language articles published up to June 2016 was performed. The manuscript was structured as a questionnaire that includes those questions that, according to the panel opinion, could generate more controversy or doubt. The initial draft was reviewed by the expert panel members to allow for modifications, and after subsequent revisions for achieving the highest degree of consensus, the final text was then validated. Different questions about diverse aspects of spasticity in adults, such as methods for evaluating spasticity, infiltration techniques, doses, number of infiltration points, etc. Regarding spasticity in children with cerebral palsy, the document included questions about minimum age of infiltration, methods of analgesia, etc. CONCLUSIONS: This review is a tool for continuous training for neurologist and rehabilitation specialist and residents of both specialties, about different specific areas of the management of BTA.


TITLE: Mitos y evidencias en el empleo de la toxina botulinica: espasticidad del adulto y del nintilde;o con paralisis cerebral.Introduccion. La espasticidad es un problema medico frecuente que impacta de forma significativa en la calidad de vida de los pacientes y sus familias. Objetivo. Analizar y dar respuesta a diferentes cuestiones en el uso de la toxina botulinica tipo A (TBA) en nuestra practica clinica habitual. Desarrollo. Un grupo de expertos en neurologia elaboro una lista de temas relacionados con el uso de la TBA. Se consideraron dos grandes bloques: espasticidad del adulto y del nintilde;o con paralisis cerebral. Se realizo una revision de la bibliografia que incluyo los diferentes articulos publicados en espantilde;ol, ingles y frances hasta junio de 2016. El documento se estructuro como un cuestionario que incluyo las preguntas que, segun el criterio del panel, podrian generar mayor controversia o duda. El borrador inicial del documento fue revisado por los miembros del panel y se realizaron las modificaciones necesarias hasta alcanzar el mayor grado de consenso. A continuacion, el texto final fue validado. Se incluyeron diferentes preguntas sobre diferentes aspectos de la espasticidad en adultos: evaluacion de la espasticidad, tecnicas de infiltracion, dosis, numero de puntos, etc. En cuanto a la espasticidad en los nintilde;os con paralisis cerebral, se analizaron preguntas como: edad minima de infiltracion, metodos de sedoanalgesia, etc. Conclusiones. Esta revision constituye una herramienta para neurologos, medicos rehabilitadores y residentes de ambas especialidades, dentro de diferentes ambitos especificos del manejo de la TBA.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Paralisia Cerebral/tratamento farmacológico , Fármacos Neuromusculares/uso terapêutico , Adolescente , Adulto , Toxinas Botulínicas Tipo A/administração & dosagem , Toxinas Botulínicas Tipo A/efeitos adversos , Paralisia Cerebral/reabilitação , Paralisia Cerebral/terapia , Criança , Pré-Escolar , Terapia Combinada , Consenso , Gerenciamento Clínico , Feminino , Objetivos , Humanos , Lactente , Masculino , Esclerose Múltipla/complicações , Esclerose Múltipla/tratamento farmacológico , Espasticidade Muscular/tratamento farmacológico , Espasticidade Muscular/terapia , Fármacos Neuromusculares/administração & dosagem , Fármacos Neuromusculares/efeitos adversos , Modalidades de Fisioterapia , Inquéritos e Questionários , Avaliação de Sintomas , Adulto Jovem
12.
Chem Commun (Camb) ; 52(23): 4305-8, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-26960420

RESUMO

The mechanism of Ph/X exchange in reactions involving SnPh(n)Bu3 and [AuXL] complexes switches dramatically from the usual concerted mechanism involving Ar/X mixed bridges when X = Cl, to an unexpected oxidative addition/reductive elimination pathway via an Au(III) intermediate when X = vinyl.

13.
J Thorac Cardiovasc Surg ; 106(3): 421-6, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8361182

RESUMO

It has frequently been suggested that early mitral commissurotomy could improve long-term results in patients with severe mitral stenosis. However, the real advantages of this procedure have yet to be demonstrated. To evaluate this hypothesis, we retrospectively studied 397 patients who underwent operation for mitral stenosis in our unit between 1978 and 1988. Forty of these patients (group I) fulfilled the criteria for early mitral commissurotomy: being young (average age 33 years), being asymptomatic or showing few symptoms, and being in sinus rhythm. The remaining 357 patients who underwent operation during the same period of time served as control (group II). Mitral valve replacement (p < 0.05) and associated tricuspid annuloplasty (p < 0.05) occurred less frequently in patients from group I than it did in patients from group II. Survival after 11 years for patients with early mitral commissurotomy was 100%, 90% of whom were in functional class I, were in sinus rhythm, and were receiving no medication whatsoever. Ninety-six percent of these patients were free of complications after 11 years, compared with 73% of patients in group II (p < 0.05). In our opinion, these results support the use of early mitral commissurotomy for young patients in sinus rhythm, who are symptom free, who are and who have a mitral valve area is 1.3 cm2 or less.


Assuntos
Estenose da Valva Mitral/cirurgia , Valva Mitral/cirurgia , Adolescente , Adulto , Feminino , Próteses Valvulares Cardíacas , Humanos , Masculino , Pessoa de Meia-Idade , Estenose da Valva Mitral/mortalidade , Reoperação , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo
14.
J Heart Lung Transplant ; 12(3): 445-8; discussion 448-9, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8329416

RESUMO

Prednisone is widely used by most heart transplant units, despite its frequent side effects. Deflazacort, a new oral synthetic steroid with fewer side effects, has not been studied in heart transplant patients. Our initial experience with 26 heart transplant patients in whom prednisone was replaced by deflazacort at 11 +/- 11 months after transplantation is reported. After the switch to deflazacort, a significant decreased was noted in glycemia, total cholesterol, and LDL-cholesterol (p < 0.001). No difference was noted in severity or frequency of rejection and infection between patients being treated with deflazacort and another 26 patients who continued to be treated with prednisone over a comparable period of time after transplantation.


Assuntos
Anti-Inflamatórios/uso terapêutico , Transplante de Coração , Pregnenodionas/uso terapêutico , Adulto , Anti-Inflamatórios/efeitos adversos , Glicemia/efeitos dos fármacos , Colesterol/sangue , Feminino , Rejeição de Enxerto/prevenção & controle , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Prednisona/efeitos adversos , Prednisona/uso terapêutico , Pregnenodionas/efeitos adversos , Triglicerídeos/sangue
15.
J Heart Lung Transplant ; 12(5): 864-8, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8241229

RESUMO

Prednisone is widely used by most heart transplantation units despite its frequent side effects. Deflazacort, an oral synthetic steroid with fewer side effects, has been successfully used in patients after heart transplantation, but a prospective study comparing deflazacort and prednisone in transplant patients is lacking. We have carried out, in the last year, a prospective trial of deflazacort versus prednisone involving 35 consecutive heart transplant patients. Two of these patients died perioperatively (surgical mortality, 5.7%), and another two were excluded from the protocol because of diabetes mellitus in one patient and active infection before transplantation in the other patient. Thus 31 patients were enrolled in the 3-month study. All of them were treated with antithymocyte globulin, 10 mg/kg/day for 3 days after transplantation, azathioprine, and cyclosporine; patients were randomly assigned groups: 15 patients to receive deflazacort therapy, 1.5 mg/kg/day, and 16 patients to receive prednisone therapy, 1 mg/kg/day, starting the first day after transplantation. Steroids were rapidly tapered, reaching the maintenance dose at 2 to 3 weeks after transplantation (prednisone, 0.15 mg/kg/day; deflazacort, 0.25 mg/kg/day). Both groups were similar in terms of age, gender, ABO identity, serum cyclosporine levels, azathioprine dosage, and pretransplantation serum glucose and lipids levels. Seven endomyocardial biopsies were performed on each patient, at 1, 2, 3, 5, 7, 10, and 13 weeks after transplantation. Incidence of acute rejection was similar between prednisone and deflazacort groups; 33% of patients receiving prednisone therapy and 42% of patients receiving deflazacort therapy had one episode of 3A or higher rejection (not significant).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Anti-Inflamatórios/uso terapêutico , Transplante de Coração , Imunossupressores/uso terapêutico , Prednisona/uso terapêutico , Pregnenodionas/uso terapêutico , Adulto , Anti-Inflamatórios/administração & dosagem , Infecções Bacterianas , Glicemia/análise , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Infecções por Citomegalovirus , Feminino , Rejeição de Enxerto/prevenção & controle , Humanos , Imunossupressores/administração & dosagem , Masculino , Pessoa de Meia-Idade , Pneumonia/etiologia , Pneumonia/microbiologia , Pneumonia Viral/etiologia , Prednisona/administração & dosagem , Pregnenodionas/administração & dosagem , Triglicerídeos/sangue
16.
J Heart Lung Transplant ; 12(6 Pt 1): 974-82, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8312322

RESUMO

In an attempt to study the influence of heart transplantation on the natural history of patients with severe congestive heart failure, we have reviewed our experience with 240 consecutive patients who were New York Heart Association class IV or III/IV, who had left ventricular ejection fraction less than 35%, who were younger than 65 years of age, and who were assessed for heart transplantation in our hospital since May 1986. Mean age was 47 +/- 12 years. Left ventricular ejection fraction was 20% +/- 6%. Eighty-seven percent were male. New York Heart Association class was IV in 88% and III/IV in 12%. The cause was ischemic heart disease in 35% of patients, valvular heart disease in 13% of patients, and primary dilated cardiomyopathy in 52% of patients. At initial assessment, heart transplantation was considered to be not indicated in 30% of patients, indicated in 51% of patients, and contraindicated in 19% of patients. During a follow-up of 13 +/- 13 months (2 to 64 months), 110 patients underwent transplantation (46%). Posttransplantation actuarial probability of survival was 70% at 3 years. Three-year probability of survival free from transplantation was significantly lower for patients older than 55 years of age (p < 0.05), for those with left ventricular ejection fraction less than 20% (p < 0.05), ischemic causes (p < 0.05), New York Heart Association class IV (p < 0.001), and indication/contraindication for transplantation (p < 0.001); no difference was noted for gender.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Insuficiência Cardíaca/cirurgia , Transplante de Coração , Análise Atuarial , Adulto , Contraindicações , Feminino , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Volume Sistólico , Taxa de Sobrevida
17.
J Heart Lung Transplant ; 14(3): 452-60, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7654730

RESUMO

BACKGROUND: Episodes of grade 1B or 2 acute heart rejection are usually not treated, and most of them resolve spontaneously. METHODS: With the aim to assess long-term outcome in patients with repetitive nontreated episodes of low-grade (1B, 2) acute rejection, we have studied 141 heart transplant recipients in whom the evolutive pattern of acute rejection during the first 6 months after transplantation could be determined. RESULTS: Forty-four patients (31%) had only grade 0 or 1A acute rejection episodes (pattern A); 23 patients (16%) had three or more episodes of grade 1B or 2 acute rejection without 3A or more advanced rejection (pattern B); 48 patients (34%) had one or two episodes of grade 3A, 3B, or 4 acute rejection only during the first 6 months after transplantation (pattern C); and 26 patients (19%) had three or more episodes of grade 3A, 3B, or 4 acute rejection (pattern D). Overall mortality was 11%, 26%, 19%, and 46% for patients with patterns A, B, C, and D, respectively. No difference was found among patterns with regard to incidence of graft atherosclerosis. Left ventricular ejection fraction at 1 year after transplantation was significantly lower (p < 0.05) for patients with pattern B (50% +/- 5% versus 59% +/- 7%, 59% +/- 11%, and 56% +/- 6% for patterns A, C, and D, respectively); cardiac index also was lower for patients with pattern B than for those with pattern A (3.6 +/- 0.6 versus 4.1 +/- 0.6 L/min/m2, p < 0.05). CONCLUSIONS: Although mortality was higher for patients with more severe episodes of acute rejection, only repetitive nontreated episodes of grade 1B or 2 rejection significantly impaired long-term graft function.


Assuntos
Rejeição de Enxerto , Transplante de Coração , Coração/fisiopatologia , Feminino , Seguimentos , Rejeição de Enxerto/mortalidade , Humanos , Terapia de Imunossupressão , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias
18.
J Heart Lung Transplant ; 14(3): 461-7, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7654731

RESUMO

BACKGROUND: Elevation in total and low-density lipoprotein cholesterol levels and a decrease in high-density lipoprotein cholesterol plasma concentrations are common in heart transplant recipients. The pathogenesis of this hyperlipemia after heart transplantation is complex. Currently available antilipemic agents are difficult to use because their adverse effects are potentiated by immunosuppressor treatment. The present investigation was carried out to test the safety and efficacy of lovastatin and bezafibrate in 18 patients with hyperlipemia after heart transplantation. METHODS: In this crossover study, after 3 months of dietary recommendations, the subjects were randomly assigned to an 8-week period of lovastatin treatment (10 mg/day) followed by an additional 8-week period of treatment with bezafibrate (400 mg/day) or vice versa. The two treatments were separated by an 8-week washout period. RESULTS: Both drugs reduced total and low-density lipoprotein cholesterol and apoprotein B concentrations. High-density lipoprotein cholesterol was only increased with bezafibrate. The total cholesterol/high-density lipoprotein cholesterol and low-density lipoprotein cholesterol/high-density lipoprotein cholesterol ratios were decreased under both treatments, but these changes were greater with bezafibrate. Apo AI levels increased with lovastatin. Bezafibrate produced a rise in high-density lipoprotein cholesterol and reduced total and very low-density lipoprotein triglycerides and very low-density lipoprotein cholesterol. Both drugs decreased intermediate density lipoprotein cholesterol and triglyceride levels, but the effect of bezafibrate on intermediate-density lipoprotein triglycerides was significantly greater. The two drugs were well tolerated and liver enzymes, creatine kinase, and renal function remained stable.


Assuntos
Bezafibrato/uso terapêutico , Transplante de Coração , Hiperlipidemias/tratamento farmacológico , Lovastatina/uso terapêutico , Adulto , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Estudos Cross-Over , Feminino , Humanos , Imunossupressores/administração & dosagem , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/tratamento farmacológico , Triglicerídeos/sangue
19.
Histol Histopathol ; 4(1): 27-30, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2485186

RESUMO

Cyclophosphamide administered at doses of 400 mg/m2/5 days with sacrifice two days later, and 200 mg/m2/5 days with a 21-day break and a further five days of treatment, with sacrifice two days later, provokes similar effects. Functional activity is less marked in untreated and control animals than in treated ones, as the hormone data shows. But the ultrastructure of PRL cells in treated animals indicates the existence of clear hormone synthesis activity, evident in the fusion and clustering of granules at differing stages of maturity, etc.


Assuntos
Ciclofosfamida/farmacologia , Adeno-Hipófise/metabolismo , Prolactina/biossíntese , Animais , Histocitoquímica , Masculino , Microscopia Eletrônica , Adeno-Hipófise/citologia , Adeno-Hipófise/efeitos dos fármacos , Ratos , Ratos Endogâmicos , Coloração e Rotulagem
20.
Histol Histopathol ; 5(2): 173-80, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2134370

RESUMO

The effects of the administration of cyclophosphamide to male rats at doses of 400 mg/m2 for a period of 5 days and of 200 mg/m2 over two five-day cycles interrupted by a 21-day break reveal differences in the ultrastructural morphology of gonadotrophic cells between treated animals and normal controls. The ultrastructural data obtained coincide with the results obtained from the measurement of serum FSH and LH levels, indicating hypofunction. A significant fall was also recorded in blood testosterone levels. The two types of treatment did not give rise to morphological or functional differences.


Assuntos
Ciclofosfamida/farmacologia , Adeno-Hipófise/efeitos dos fármacos , Animais , Grânulos Citoplasmáticos/ultraestrutura , Retículo Endoplasmático/ultraestrutura , Hormônio Foliculoestimulante/metabolismo , Complexo de Golgi/ultraestrutura , Hormônio Luteinizante/metabolismo , Masculino , Microscopia Eletrônica , Mitocôndrias/ultraestrutura , Adeno-Hipófise/metabolismo , Adeno-Hipófise/ultraestrutura , Ratos , Ratos Endogâmicos , Testosterona/metabolismo
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