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1.
J Phys Chem Lett ; 12(40): 9894-9898, 2021 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-34609889

RESUMEN

The current understanding of the dynamics of gas-surface interactions is that all of the energy lost in the collision is transferred to vibrations of the target. Electronic excitations were shown to play a marginal role except for cases in which the impinging particles have energies of several electronvolts. Here we show that this picture does not hold for metal surfaces supporting acoustic surface plasmons. Such loss, dressed with a vibronic structure, is shown to make up a prominent energy transfer route down to the terahertz region for Ne atoms scattering off Cu(111) and is expected to dominate for most metals. This mechanism determines, e.g., the drag force acting on telecommunication satellites, which are typically gold-plated to reduce overheating by sunshine. The electronic excitations can be unambiguously discerned from the vibrational ones under mild hyperthermal impact conditions.

2.
Kasmera ; 46(1): 9-16, ene.-jun 2018. tab
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1008082

RESUMEN

Las infecciones helmínticas intestinales que afectan al hombre están íntimamente ligadas a condiciones ecológicas, humanas y/o sociales que pueden favorecer o no su persistencia. El objetivo del presente trabajo fue presentar la casuística de las infecciones helmínticas intestinales que se diagnosticaron en el Laboratorio Clínico Asistencial del Ambulatorio Urbano Tipo III Los Curos entre los años 2012 a 2015. Para tal fin se realizó una investigación retrospectiva donde se estudiaron para el período evaluado los registros del laboratorio. Los resultados evidenciaron 61,7% de individuos parasitadas, 1,9% con algún helminto (Ascaris lumbricoides, Trichuris trichiura, Strongyloides stercoralis, Enterobius vermicularis, Hymenolepis nana o Ancylostomideos). No se evidenció diferencia entre la presencia de helmintos y los parámetros demográficos edad o género. Se concluye que las condiciones ecoepidemiológicas de Los Curos no son lo suficientemente aptas para el mantenimiento de infecciones helmínticas intestinales.


The intestinal helminth infections that affect man are intimately linked to ecological, human and / or social conditions that may or not allow their persistence. The objective of the present study was to present the casuistry of the intestinal helminth infections that were diagnosed in the Clinical Laboratory of the Ambulatory Urban III Los Curos between the years 2012 to 2015. For that purpose, a retrospective investigation was carried out where they were studied for the period laboratory records were evaluated. The results evidenced 61.7% of parasitized individuals, 1.9% with some helminth (Ascaris lumbricoides, Trichuris trichiura, Strongyloides stercoralis, Enterobius vermicularis, Hymenolepis nana or Ancylostomideos). There was no difference between the presence of helminths and the demographic parameters age or sex. It is concluded that the ecoepidemiological conditions of Los Curos are not sufficiently adequate for the maintenance of intestinal helminth infections.

4.
Ann Surg Oncol ; 16(5): 1122-7, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19255809

RESUMEN

BACKGROUND: Quadrantectomy is an oncological safe procedure for early breast cancer, but it often results in poor aesthetic results such as breast shape deformity, more visible if the tumor is located in the upper pole. We suggest the use of a modified Wise-pattern breast reduction in patients with moderate to severe breast hypertrophy and tumor located in upper quadrants that keeps the oncological advantages of the quadrantectomy but with better aesthetical results. MATERIAL AND METHODS: Quadrantectomy of the upper quadrant, immediate breast reconstruction and contralateral breast reduction to obtain symmetry was performed on 11 patients affected by early breast cancer with bra cup size from C to E. To replace the skin area removed with mastectomy from the upper quadrants, a similar-size area from the lower pole was preserved. RESULTS: All patients healed uneventfully within 15 days, and no local or distant recurrences occurred with mean follow-up of 26.5 months (range 19-39 months). In all cases natural breast shape was achieved. The scars were similar to a reduction mammaplasty, and the medial or lateral scar on the upper quadrant did not aesthetically disfigure the décolleté. CONCLUSIONS: Modified Wise-pattern reduction mammaplasty is a valid technique as immediate breast reconstruction to obtain a natural breast mound after upper quadrantectomies on patients with medium/large breasts.


Asunto(s)
Neoplasias de la Mama/cirugía , Mama/cirugía , Mamoplastia/métodos , Adulto , Femenino , Humanos , Mastectomía Segmentaria , Persona de Mediana Edad
5.
J Prev Med Hyg ; 50(3): 141-9; quiz 150-1, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20411647

RESUMEN

High rates of pediculosis are found in every part of the world. The age-range most affected is between 3 and 12 years. No-nit policies are ineffective in preventing infestations. On the other hand, misdiagnosis and overuse of pediculicides, increase resistance to treatment. Lack of information leads people to consider this kind of infestation to be associated to low social classes and immigrants. This research has been implemented to find out about the information level on pediculosis on a sample of students (722) and teachers (408) of some primary schools in northern and southern Italy, and to highlight the role of personal aspects such as age, gender, cultural level, geographical position which may influence this topic and, eventually, allow the use of the correct knowledge in developing appropriate procedures within the school district. Data was obtained through a questionnaire containing 21 multiple choice questions for the teachers and 14 for the students. Standard descriptive statistics were computed. chi2 tests were applied to highlight statistical association among observed variables; test for the difference of two proportions were applied to confirm significant differences among the observed proportions. The level of information for students seems to be, approximately, the same both for northern and southern Italy. There was a slight prevalence of correct answers from southern teachers, probably because the phenomenon of pediculosis has a positive trend of growth in the south. The number of correct answers was, for all, on average about 60.0%; a negative result in itself considering the simplicity of the questions. Knowledge about the biology of the louse was virtually absent. The area of prevention showed lack of information and need for improvement. Most of the teachers believe that there are specific products that can prevent infestation by louse. Most of the teachers have information which does not come from scientific sources. Students receive some short and incomplete information from their parents. Deficiencies in teachers' knowledge indicate that they are inadequately equipped to manage lice infestation. Educational interventions with teachers and families and, as a consequence, with students should be taught at school to allow a correct understanding of the pediculosis, increasing the teachers' competence and, consequently, as soon as the infestation should manifest, a rapid alert of the Health Service so that proper treatment could be provided.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Infestaciones por Piojos/psicología , Pediculus , Dermatosis del Cuero Cabelludo/psicología , Percepción Social , Adulto , Animales , Niño , Cultura , Docentes , Femenino , Geografía , Educación en Salud , Humanos , Italia/epidemiología , Infestaciones por Piojos/epidemiología , Infestaciones por Piojos/prevención & control , Masculino , Persona de Mediana Edad , Salud Pública , Dermatosis del Cuero Cabelludo/epidemiología , Dermatosis del Cuero Cabelludo/prevención & control , Instituciones Académicas/estadística & datos numéricos , Factores Socioeconómicos , Estudiantes , Encuestas y Cuestionarios
6.
Microb Ecol ; 52(1): 72-89, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16733620

RESUMEN

We investigated the dynamics and diversity of heterotrophic bacteria, autotrophic and heterotrophic flagellates, and ciliates from March to July 2002 in the surface waters (0-50 m) of Lake Bourget. The heterotrophic bacteria consisted mainly of "small" cocci, but filaments (>2 microm), commonly considered to be grazing-resistant forms under increased nanoflagellate grazing, were also detected. These elongated cells mainly belonged to the Cytophaga-Flavobacterium (CF) cluster, and were most abundant during spring and early summer, when mixotrophic or heterotrophic flagellates were the main bacterial predators. The CF group strongly dominated fluorescent in situ hybridization-detected cells from March to June, whereas clear changes were observed in early summer when Beta-proteobacteria and Alpha-proteobacteria increased concomitantly with maximal protist grazing pressures. The analysis of protist community structure revealed that the flagellates consisted mainly of cryptomonad forms. The dynamics of Cryptomonas sp. and Dinobryon sp. suggested the potential importance of mixotrophs as consumers of bacteria. This point was verified by an experimental approach based on fluorescent microbeads to assess the potential grazing impact of all protist taxa in the epilimnion. From the results, three distinct periods in the functioning of the epilimnetic microbial loop were identified. In early spring, mixotrophic and heterotrophic flagellates constituted the main bacterivores, and were regulated by the availability of their resources mainly during April (phase 1). Once the "clear water phase" was established, the predation pressure of metazooplankton represented a strong top-down force on all microbial compartments. During this period only mixotrophic flagellates occasionally exerted a significant bacterivory pressure (phase 2). Finally, the early summer was characterized by the highest protozoan grazing impact and by a rapid shift in the carbon pathway transfer, with a fast change-over of the main predators contribution, i.e., mixotrophic, heterotrophic flagellates and ciliates in bacterial mortality. The high abundance of ciliates during this period was consistent with the high densities of resources (heterotrophic nanoflagellates, algae, bacteria) in deep layers containing the most chlorophyll. Bacteria, as ciliates, responded clearly to increasing phytoplankton abundance, and although bacterial grazing impact could vary largely, bacterial abundance seemed to be primarily bottom-up regulated (phase 3).


Asunto(s)
Bacterias , Ecosistema , Eucariontes , Agua Dulce/microbiología , Agua Dulce/parasitología , Animales , Bacterias/clasificación , Bacterias/aislamiento & purificación , Fenómenos Fisiológicos Bacterianos , Biodiversidad , Biomasa , Clorofila/análisis , Clorofila A , Recuento de Colonia Microbiana , Eucariontes/clasificación , Eucariontes/aislamiento & purificación , Eucariontes/fisiología , Francia , Hibridación Fluorescente in Situ , Plancton
7.
Ann Oncol ; 14(1): 105-9, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12488301

RESUMEN

BACKGROUND: In gastric juice, high levels of the carcinoembryonic antigen (CEA) and the carbohydrate antigen 19-9 (CA 19-9) have been found to correlate with precancerous lesions and gastric cancer. So far, sampling of gastric juice has required upper endoscopy. In place of this invasive procedure, we investigated a new tool for the quantitation of tumor markers in gastric juice. MATERIALS AND METHODS: The study population consisted of healthy controls and consecutive subjects with suspected gastric cancer or dyspepsia/epigastric distress. Patients were asked to swallow a small gelatine capsule (14 mm in length and 5 mm in diameter) containing a pierced plastic cover and surrounding a piece of absorbent paper. The capsule was left in the gastric cavity for 60 min to allow saturation of the absorbent paper with gastric juice. A 45-50 cm length of nylon thread connected to the inner capsule was used to remove the device from the gastric cavity. After processing the absorbent paper for radioimmunoassay, CEA and CA 19-9 levels were correlated to the findings of upper endoscopy and biopsies of gastric mucosa or suspected lesions. RESULTS: The endogastric capsule did not cause any side-effects and 62 participants were fully compliant to the procedure. Assessable gastric juice samples were taken from 23 patients with gastric cancer, 15 patients with intestinal metaplasia or dysplasia, 12 patients with gastritis and 12 controls without gastric diseases. In the 12 samples of gastric juice from control patients, mean values of CEA and CA 19-9 were 1.1 +/- 0.9 ng/ml and 16 +/- 7.5 ng/ml, respectively. The mean levels of both markers were found to increase according to the severity of gastric lesions and in patients with cancer, mean CEA and CA 19-9 levels were 513 +/- 627 ng/ml and 545 +/- 510 ng/ml, respectively. Patients with precancerous lesions and cancer showed higher levels of CEA and CA 19-9 than patients with normal findings or gastritis (P <0.001). CONCLUSIONS: The endogastric capsule is a simple, non-invasive tool for the measurement of CEA and CA 19-9 levels in gastric juice. These values may discriminate between normal or minor pathologic changes and precancerous lesions or carcinomas. Further investigations are warranted, since this may represent a new method for gastric cancer screening.


Asunto(s)
Antígeno CA-19-9/análisis , Cápsulas/administración & dosificación , Antígeno Carcinoembrionario/análisis , Jugo Gástrico/química , Neoplasias Gástricas/química , Neoplasias Gástricas/diagnóstico , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Diagnóstico Diferencial , Endoscopía , Femenino , Gastritis/diagnóstico , Gastritis/inmunología , Humanos , Masculino , Metaplasia/diagnóstico , Metaplasia/inmunología , Persona de Mediana Edad , Estadificación de Neoplasias , Lesiones Precancerosas/diagnóstico , Estudios Prospectivos , Radioinmunoensayo , Factores de Riesgo , Seguridad , Manejo de Especímenes
8.
Minerva Chir ; 57(3): 289-93, 2002 Jun.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-12029222

RESUMEN

BACKGROUND: A mutilated foot as a result of traumas or resection for tumours or ulcers, is a serious physical and social handicap for the patient, because it impairs deambulation and affects his selfgovernment. The evolution of microsurgical techniques has allowed us to utilize such methods to reconstruct wide simple and composite losses of substance of the foot, usually treated conservatively or radically with amputation and prosthesization. Functional, cosmetic and social outcome has been evaluated. METHODS: We evaluated 23 patients affected by cutaneous (19) and osteocutaneous (4) losses of substance of the foot (11 of rearfoot, 5 of forefoot, 4 of the sole, 1 of middlefoot, 1 of the dorsum, and 1 of the malleolus). We performed 23 microsurgical reconstructions harvesting 24 free flaps (14 radial flaps, 4 latissimus dorsi, 3 fibula, 1 scapular flap, 1 lateral arm, 1 iliac crest). RESULTS: Cutaneous and muscular flaps healed in 3 weeks, while osteocutaneous flaps healed in 10 to 12 weeks. Deambulation was restored in all patients but 1, within 6 months from surgery, and all patients went back to their work and social life. We observed in the early follow-up 2 cases of partial skin necrosis, which solved spontaneously and 1 case of total necrosis (overall complication = 4.3%). Donor area morbidity was rated as fair. Overall success rate was 95.7% at a mean follow-up of 3 years. CONCLUSIONS: Free microsurgical transfers allowed us to obtain a satisfactory and long-lasting morpho-functional restoration of wide superficial and deep losses of substance of the foot, guaranteeing the patient a fast psycho-physical and social rehabilitation.


Asunto(s)
Traumatismos de los Pies/cirugía , Microcirugia , Procedimientos de Cirugía Plástica/métodos , Colgajos Quirúrgicos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Cicatrización de Heridas
9.
Scand J Plast Reconstr Surg Hand Surg ; 35(3): 301-4, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11680400

RESUMEN

We report the follow-up of 47 patients with penile hypospadias who were treated by the Scuderi procedure between 1988 and 1998 at Sahlgrenska University Hospital, Göteborg, Sweden. Forty of the patients (85%) had had no previous operations, while the remaining seven had had meatotomy with chordectomy only, or an unsuccessful Dennis-Browne procedure. Hypospadias was distal in 35 (74%), mediopenile in 8 (17%), and proximal in 4 (9%); 21 (45%) showed signs of curvature. After a Scuderi urethroplasty one patient developed a fistula (2%) and 4 developed mild stenosis. The early success rate was therefore 42/47 (89%) and this later increased to 46/47 (98%) after non-surgical treatment of the stenoses. The results support the use of the Scuderi procedure for correction of primary and secondary penile hypospadias with a low complication rate.


Asunto(s)
Hipospadias/cirugía , Colgajos Quirúrgicos , Niño , Estudios de Seguimiento , Humanos , Masculino , Complicaciones Posoperatorias/epidemiología , Factores de Tiempo , Uretra/cirugía
10.
Minerva Chir ; 56(2): 161-7, 2001 Apr.
Artículo en Italiano | MEDLINE | ID: mdl-11353349

RESUMEN

A case report of a 44 year-old white man admitted to the surgical unit for a bilateral simultaneous pneumothorax is presented. The pneumothorax occurred on day one after a surgical operation for discal hernia; in the past the patient already presented a right spontaneous pneumothorax at 32 years of age and a left pneumothorax at 37 years of age, both treated with a pleural drainage. A thoracic drain was bilaterally positioned with a good result only in the right side. The persistence of the left pneumothorax induced the authors to perform a postero-lateral thoracotomy bullae excision and pleurectomy with a good postoperative course. After a few months a new right pneumothorax occurred and the patient was treated with a right postero-lateral thoracotomy, bullae resection and pleurectomy. On the basis of the case reported, the authors consider the different opportunities in the treatment of spontaneous pneumothorax in relation to the present knowledges and technologies. Surgical procedure is to be preferred in case of persistence of pneumothorax despite a pleural drain and in case of pneumothorax in high risk subjects. Even if thoracoscopy seems to give better results regarding postoperative pain, it is not always possible with such a method to perform a careful pleurectomy neither to obtain it in all cases (above all in secondary pneumothorax). Every case must then be carefully studied to choose the best treatment at present available.


Asunto(s)
Neumotórax/cirugía , Adulto , Humanos , Masculino , Pleura/cirugía , Neumotórax/diagnóstico por imagen , Radiografía Torácica , Recurrencia , Toracoscopía , Toracotomía
11.
Minerva Chir ; 55(4): 227-34, 2000 Apr.
Artículo en Italiano | MEDLINE | ID: mdl-10859956

RESUMEN

BACKGROUND: The surgical treatment of large wall defects conventionally defined as an extension over 10 cm is discussed. The difficulty to contain the bowels that have lost law of domicile in the abdominal hollow, constitutes motive for notable increase of the endo-abdominal Pressure with serious consequences in the postoperative course and this leads to the use of prothesis meshes that allow the closing of the abdominal hollow with the Tension-Free technique. METHODS: Personal experience embraces 45 patients, with large wall defects, divided into 21 patients with overumbilical location, 14 with umbilical location, 10 with periumbelical location; a simple suture has been used in 7 cases, the reconstruction of the wall according to Stoppa in 36 cases and the apposition of Goretex net internally and Marlex net externally in 2 cases. RESULTS: There have been neither mortality, neither recidivists of illness, but only some complications: 9 cases of superficial infection, 1 case of intestinal occlusion and 2 of subcutaneous seroma. CONCLUSIONS: According to their experience and wide literature review, the authors draw some conclusions: an accurate toilet and a careful evaluation of the respiratory functionality are fundamental; it's necessary to postpone surgical intervention in presence of local inflammation and, where this is improrogable it's opportune to avoid the use of prothesis meshes or refold on readsorbible prothesis; special care must be taken to the hemostasis and an aspirative drain for 24-48 hrs preserves from the risk of postoperative hematomas and following local infections. The submuscular mesh permits a Tension-Free suture and for this reason it would have nowdays a more extensive use. Finally it's pointed out the choice of a PTFEe mesh in contact with the intestinal skein.


Asunto(s)
Hernia Ventral/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Hernia Ventral/patología , Humanos , Masculino , Persona de Mediana Edad
12.
Aesthetic Plast Surg ; 24(6): 395-400, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11246425

RESUMEN

Recently ultrasound assisted liposuction (UAL) and pneumatic assisted liposuction (PAL) have been introduced as an attempt to improve the results and reduce the pitfalls of standard liposuction (SAL). Until now no studies comparing, at the same time, UAL, PAL, and SAL have been published. The aim of this study was to analyze these methods from the surgeon's point of view, focusing not only on aesthetic results but also on local and systemic trauma, efficacy, handling, and cost. Forty-five cosmetic patients affected by local lipodystrophy, divided into three equal groups, have undergone liposuction with the three above-mentioned techniques. Quantitative and qualitative analysis of lipoaspirates, together with blood chemistry, local and systemic complications, time to aspirate 100 cm3, distress, fatigue, and costs of the procedures, has been recorded. Our results showed bloodier lipoaspirates in SAL and a higher percentage of triglycerides in UAL lipoaspirates. Blood tests revealed a slight decrease in the postoperative Hb in SAL only. Early complications observed were four erythemas in PAL, three ecchymoses in SAL, and one long-lasting edema in UAL. Aesthetic results rated by independent viewers were similar for all methods. Efficacy was higher in the PAL group (4 min x 100 cm3 fat aspirated) than in SAL (7 min x 100 cm3 fat) and UAL (10 min x 100 cm3 fat). Surgeon's distress was higher in PAL than in SAL and UAL. Surgeon's fatigue was much lower in the PAL group than in the others. Costs expressed as multiples of 1 unit (1 unit = $500 U.S.) were highest for UAL, low for PAL, and lowest for SAL. In conclusion, PAL and UAL caused reduced vascular injury, UAL being more selective for adipocyte removal. Complications of UAL and PAL were mostly related to the longer learning curve of these methods. The UAL procedure was much more expensive than PAL and, especially, SAL. PAL proved to be a handy technique, with the most favorable cost/benefit ratio, and seems to be the best option for busy liposuction practices or fast office procedures, even though the choice of the ideal technique always depends on the surgeon's preference.


Asunto(s)
Lipectomía/métodos , Análisis Costo-Beneficio , Costos y Análisis de Costo , Equimosis/etiología , Edema/etiología , Eritema/etiología , Estética , Hemoglobinas/análisis , Humanos , Lipectomía/efectos adversos , Lipectomía/economía , Pautas de la Práctica en Medicina , Succión , Triglicéridos/análisis , Ultrasonido
13.
J Cardiovasc Surg (Torino) ; 40(3): 363-72, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10412921

RESUMEN

BACKGROUND: Previous studies have demonstrated that hibernating myocardium can be assessed by [18F]fluorodeoxyglucose ([18F]FDG) and positron emission tomography (PET). This study evaluated the use of [18F]FDG-PET for CABG related risk assessment in patients with coronary artery disease (CAD) and left ventricle dysfunction (LVD). METHODS: We retrospectively evaluated 241 to patients candidate CABG presenting with signs and symptoms of congestive heart failure (CHF) prevailing over ischemic signs. Of the 241 patients, 153 had undergone [18F]FDG-PET as well as conventional assessment: 110 out of 153 (group A) were operated because of PET evidence of hibernation. Of the 241 patients, 88 had not undergone [18F]FDG-PET: 86 out of 88 (group B) were operated on. The outcome of surgical patients was evaluated by considering all major perioperative complications including the use of mechanical and pharmacological support and in-hospital mortality. After hospital discharge, each patient was examined at 1, 4 and every 6 months thereafter. RESULTS: Perioperative use of mechanical supports and inotropic drugs, was significantly lower for the PET selected group (A) than for the non PET selected group (B). Mortality within 30 days of surgery was 0.9% in group A and 19.8% in group B. The only predictors of perioperative outcome were the presence of hibernating tissue and the ejection fraction. CONCLUSIONS: [18F]FDG-PET prior to CABG can be crucial for the assessment of perioperative risk in patients with CAD.


Asunto(s)
Puente de Arteria Coronaria , Enfermedad Coronaria/cirugía , Fluorodesoxiglucosa F18 , Aturdimiento Miocárdico/diagnóstico por imagen , Radiofármacos , Tomografía Computarizada de Emisión/métodos , Disfunción Ventricular Izquierda/cirugía , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/terapia , Toma de Decisiones , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Medición de Riesgo , Tasa de Supervivencia , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/terapia
14.
Rays ; 24(1): 81-95, 1999.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-10358386

RESUMEN

An improvement of regional and global left ventricle dysfunction can be achieved in patients with coronary artery disease either by coronary revascularization with percutaneous transluminal coronary angioplasty or coronary artery bypass grafting. Several techniques have been developed to identify dysfunctional but viable myocardium. In the last decade, positron emission tomography (PET) with 18F-fluorodeoxyglucose (18F-FDG) has been used for the detection of hibernating myocardium. It can accurately predict the recovery of abnormal wall motion in hibernating segments prior to surgery. In particular, assessment of viability with 18F-FDG is indicated in high-risk surgical candidates being considered for revascularization or transplantation. Moreover, patient selection criteria and economic consideration are also relevant for cost-effective use of the technique.


Asunto(s)
Enfermedad Coronaria/diagnóstico por imagen , Miocardio/patología , Tomografía Computarizada de Emisión , Angioplastia Coronaria con Balón , Puente de Arteria Coronaria , Enfermedad Coronaria/fisiopatología , Enfermedad Coronaria/cirugía , Enfermedad Coronaria/terapia , Análisis Costo-Beneficio , Fluorodesoxiglucosa F18 , Predicción , Trasplante de Corazón , Humanos , Contracción Miocárdica/fisiología , Aturdimiento Miocárdico/diagnóstico por imagen , Aturdimiento Miocárdico/fisiopatología , Miocardio/metabolismo , Selección de Paciente , Radiofármacos , Factores de Riesgo , Supervivencia Tisular , Tomografía Computarizada de Emisión/economía , Tomografía Computarizada de Emisión/métodos , Resultado del Tratamiento , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Izquierda/cirugía , Disfunción Ventricular Izquierda/terapia
15.
Acta Diabetol ; 35(2): 67-73, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9747956

RESUMEN

We propose modified warm blood antegrade-retrograde reperfusion (WBARR) of arrested hearts as a metabolic model with which to study substrate exchange and energy metabolism during the recovery phase after 90 min of ischaemia in man. Eleven anaesthetized patients undergoing aorto-coronary bypass were studied during WBARR. The protocol was designed as follows: period 1, a warm blood reperfusion with potassium (3 min); period 2, a warm blood reperfusion without potassium (2 min). The perfusion flow rate averaged 250+/-2 ml/min at the beginning of period 1 and 218+/-19 ml/min at the beginning and at the end of period 2; the perfusion was performed antegradely and retrogradely in the arrested hearts. Samples were simultaneously taken from the coronary venous sinus (CVS) and from the aortic root needle (AR). At the beginning of WBARR lactate release was 85+/-44 micromol/min and at the end it had significantly decreased to 21+/-99 micromol/min (P<0.03). Simultaneously, non-esterified fatty acids (NEFA) and beta-hydroxy-butyrate were initially released (71+/-61 and 22+/-66 micromol/min, respectively), while at the end of the WBARR there was an uptake of both NEFA (20+/-22 micromol/min; P<0.01) and beta-hydroxy-butyrate (12+/-35 micromol/min; P=0.290). Alanine, glycerol and branched chain amino acid balance across the heart did not significantly change. In summary after 90 min of ischaemia the heart energy metabolism is mainly anaerobic and based on glucose consumption, with lactate, NEFA and amino acids, which are mainly released. After 5 min of WBARR (recovery from ischaemia), lactate release is significantly reduced and NEFA becomes the energy supply of the heart. In conclusion, (1) WBARR is a valuable method with which to study myocardial metabolism in anaesthetized humans and may be combined with the use of tracers; (2) the study of myocardial metabolism in arrested hearts eliminates the imprecisions arising from the noncontinuous coronary blood flow; (3) NEFA become an important source of energy utilized by human hearts in the recovery phase from ischaemia.


Asunto(s)
Sangre , Calor , Isquemia Miocárdica/metabolismo , Reperfusión Miocárdica , Miocardio/metabolismo , Adulto , Anciano , Alanina/metabolismo , Metabolismo Energético/fisiología , Ácidos Grasos no Esterificados/metabolismo , Femenino , Humanos , Ácido Láctico/metabolismo , Masculino , Persona de Mediana Edad , Consumo de Oxígeno/fisiología
16.
Heart ; 79(3): 242-7, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9602656

RESUMEN

OBJECTIVE: To determine whether preoperative left ventricular ejection fraction (LVEF) is related to the degree of myocardial oxidative stress during bypass surgery in man. DESIGN: Observational study. SETTING: Tertiary care centre. PATIENTS AND INTERVENTIONS: 31 patients (LVEF range was 20% to 68%) undergoing elective coronary bypass surgery with blood cardioplegic reperfusion were studied. Arterial and coronary sinus blood was collected before aortic cross clamping (T0) and at 0 (T1), 15 (T2), and 30 (T3) minutes after unclamping. Transmural left ventricular biopsies were also obtained from 15 patients at T0 and at T1. MAIN OUTCOME MEASURES: Glutathione and adenine nucleotides were measured in myocardial biopsies, while coronary sinus-artery differences for glutathione, nucleotides, and products of lipid peroxidation were calculated from blood specimens. Creatine kinase (myocardial band; CK-MB) was measured in plasma at four and 12 hours after operation. RESULTS: Myocardial glutathione and adenine nucleotides were correlated (p < 0.02) with preoperative LVEF both at T0 (r = 0.909 and 0.672) and T1 (r = 0.603 and 0.605). Oxidised glutathione released from the heart during reperfusion was inversely correlated with LVEF (r = -0.448, -0.466, and -0461 at T1, T2, and T3, p < 0.01), while reduced glutathione (r = 0.519 and 0.640 at T1 and T2) and glutathione redox ratio (r = 0.647, 0.714, 0.645, and 0.702 at T0, T1, T2, and T3) showed a direct correlation (p < 0.01). Lipid peroxidation at T1 was negatively related to LVEF (r = -0.492). CK-MB was also negatively related to LVEF (r = -0.440 at 4 h and -0.462 at 12 h). CONCLUSIONS: The capacity to counterbalance oxidative burst following ischaemia and reperfusion appears to be related to the functional ability of the heart.


Asunto(s)
Puente de Arteria Coronaria , Enfermedad Coronaria/cirugía , Miocardio/metabolismo , Estrés Oxidativo , Volumen Sistólico , Nucleótidos de Adenina/metabolismo , Anciano , Biomarcadores , Enfermedad Coronaria/metabolismo , Femenino , Glutatión/sangre , Glutatión/metabolismo , Humanos , Hipoxantinas/metabolismo , Peroxidación de Lípido , Masculino , Persona de Mediana Edad , Oxidación-Reducción , Función Ventricular Izquierda
17.
J Comput Aided Mol Des ; 11(5): 425-45, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9385547

RESUMEN

This paper describes the development of a simple empirical scoring function designed to estimate the free energy of binding for a protein-ligand complex when the 3D structure of the complex is known or can be approximated. The function uses simple contact terms to estimate lipophilic and metal-ligand binding contributions, a simple explicit form for hydrogen bonds and a term which penalises flexibility. The coefficients of each term are obtained using a regression based on 82 ligand-receptor complexes for which the binding affinity is known. The function reproduces the binding affinity of the complexes with a cross-validated error of 8.68 kJ/mol. Tests on internal consistency indicate that the coefficients obtained are stable to changes in the composition of the training set. The function is also tested on two test sets containing a further 20 and 10 complexes, respectively. The deficiencies of this type of function are discussed and it is compared to approaches by other workers.


Asunto(s)
Diseño de Fármacos , Endopeptidasas/química , Ligandos , Unión Proteica , Proteínas/química , Sitios de Unión , Análisis de Regresión , Programas Informáticos , Termodinámica
18.
Heart ; 77(5): 449-55, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9196416

RESUMEN

OBJECTIVE: To evaluate the role of leucocytes in free radical production in patients with depressed or normal ejection fraction undergoing coronary bypass. DESIGN: Two randomised control trials. SETTING: Tertiary care centre. PATIENTS AND INTERVENTIONS: In the first study, 22 patients with ejection fractions of < or = 40% received blood cardioplegic reperfusion with (n = 11) or without (n = 11) leucocyte depletion. In the second study, 22 patients with ejection fractions > or = 45% received either leucocyte depleted (n = 11) or blood cardioplegia (n = 11). MAIN OUTCOME MEASURES: Glutathione, hypoxanthine, and lipid peroxidation products were measured in coronary sinus blood and plasma before aortic cross clamping and at 0, 15, and 30 minutes after unclamping. Haemodynamic variables and creatine kinase MB isoenzymes were monitored on the first postoperative day. Comparison between treatments was performed on difference (delta) between measurements at time 0 and at baseline, and on slopes obtained by fitting measurements after unclamping with a linear regression model. RESULTS: At unclamping no difference in delta for plasma glutathione redox ratio (oxidised/total glutathione, %) was observed between treated and control groups with low ejection fraction (delta = 16 (SD 8.39) and 24 (7.0) redox ratio %, respectively). Baseline value recovery rate (redox ratio %/min) was significantly faster in treated v control patients (slope -0.912 (0.380) v -0.158 (0.200), P < 0.005, respectively). Cardiac index showed a trend to greater improvement in the treated group (slope 0.04 (0.03) v 0.003 (0.002) 1/min/m2/h, P < 0.02, treated v controls, respectively). In patients with normal ejection fraction, leucocyte depletion did not result in significant improvement v controls. CONCLUSIONS: Leucocyte depletion seems to provide benefit only in patients with left ventricular dysfunction.


Asunto(s)
Enfermedad Coronaria/sangre , Glutatión/sangre , Hipoxantina/sangre , Leucocitos/fisiología , Peroxidación de Lípido , Revascularización Miocárdica , Anciano , Puente Cardiopulmonar , Enfermedad Coronaria/cirugía , Radicales Libres , Paro Cardíaco Inducido , Humanos , Persona de Mediana Edad , Oxidación-Reducción
19.
J Heart Valve Dis ; 6(2): 138-44, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9130121

RESUMEN

BACKGROUND AND AIMS OF THE STUDY: In this study, we reviewed our experience in heart valve replacement with the St. Jude BioImplant heart valve, which is a low-profile, low-pressure glutaraldehyde-fixed porcine prosthesis mounted on a flexible Delrin stent. METHODS: During the period May 1989-January 1996, 117 patients were implanted with 132 BioImplant prostheses; three patients were lost to follow up and excluded from the series. Mean age was 67.5 +/- 9.8 years (range: 19 to 82 years); myocardial revascularization was performed in 22 (19.3%) patients. In-hospital mortality rate was 6% (7/117 patients). By January 1996, 114 patients (53 males, 61 females), in whom 59 aortic, 35 mitral, 15 mitro-aortic and five tricuspid prostheses had been implanted, were eligible for the analysis. Mean follow up was 40.4 +/- 21.7 months (range: 1 to 76 months). RESULTS: The survival probability of survivors was 72.1 +/- 6.5 at 77 months. Seventeen patients died during follow-up. The mean NYHA class improved from 3.1 +/- 0.6 preoperatively to 1.4 +/- 0.6 postoperatively. The freedom probabilities were respectively 89.5 +/- 5.3% from thromboembolism, 93.2 +/- 3.7% from infective endocarditis, 84.5 +/- 10.3% from structural dysfunction, 99.1 +/- 0.9% from non-structural dysfunction, and 80.1 +/- 10.2% from reoperation. The freedom probability for valve-related events was respectively 75.3 +/- 12.3%, 98.0 +/- 1.9% and 67.2 +/- 17.2% for patients who underwent mitral, aortic and mitro-aortic heart valve replacement (p = 0.05 comparing only patients who underwent mitral or aortic replacement); moreover the freedom probability from valve-related events was 71.6 +/- 11.2% in patients aged < or = 65 years and 90.2 +/- 6.6% in patients aged > 65 years (p = 0.006). CONCLUSIONS: The BioImplant heart valve, in our experience, seems to be a valuable device which shows a mid-term performance similar to that of other porcine prostheses.


Asunto(s)
Enfermedades de las Válvulas Cardíacas/cirugía , Complicaciones Posoperatorias/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Animales , Bioprótesis , Endocarditis/epidemiología , Endocarditis/etiología , Seguridad de Equipos , Estudios de Evaluación como Asunto , Femenino , Estudios de Seguimiento , Enfermedades de las Válvulas Cardíacas/mortalidad , Enfermedades de las Válvulas Cardíacas/fisiopatología , Prótesis Valvulares Cardíacas/efectos adversos , Hemodinámica , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Probabilidad , Pronóstico , Diseño de Prótesis , Falla de Prótesis , Reoperación , Factores de Riesgo , Análisis de Supervivencia , Porcinos , Trombosis/epidemiología , Trombosis/etiología , Factores de Tiempo
20.
Ann Urol (Paris) ; 31(2): 101-2, 1997.
Artículo en Francés | MEDLINE | ID: mdl-9245248

RESUMEN

The authors present their technique of local anaesthesia in the surgical treatment of phimosis using a cream composed of an eutectic mixture of lidocaine and prilocaine (Emla). This cream, unlike injectable local anaesthetics, allows surgical procedures to be performed on the prepuce without pain.


Asunto(s)
Anestésicos Locales , Lidocaína , Pomadas , Fimosis/cirugía , Prilocaína , Adulto , Niño , Combinación de Medicamentos , Estudios de Evaluación como Asunto , Humanos , Combinación Lidocaína y Prilocaína , Masculino
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