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1.
Transpl Infect Dis ; 17(1): 129-36, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25620391

RESUMEN

Pseudoaneurysms (PAs) developing at the site of vascular anastomosis after organ transplantation are a rare but serious complication. We report a series of 3 cases of PA observed in a single center over a period of 18 years. The mode of presentation was acute bleeding in 2 cases. In the third patient, who underwent combined kidney and pancreas transplantation, the PA on the renal graft was discovered by chance. Graft removal associated with iliac artery ligation and extra-anatomic femoro-femoral bypass represents the standard treatment. However, interposition of a venous homograft may allow preservation of inferior limb perfusion and possibly graft salvage.


Asunto(s)
Aneurisma Falso/terapia , Candidemia/tratamiento farmacológico , Trasplante de Riñón/efectos adversos , Trasplante de Páncreas/efectos adversos , Complicaciones Posoperatorias , Infecciones por Pseudomonas/tratamiento farmacológico , Adulto , Anastomosis Quirúrgica , Aneurisma Falso/etiología , Aneurisma Falso/microbiología , Aneurisma Falso/cirugía , Candida albicans/aislamiento & purificación , Candidemia/diagnóstico , Candidemia/microbiología , Niño , Humanos , Arteria Ilíaca/cirugía , Masculino , Infecciones por Pseudomonas/diagnóstico , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/aislamiento & purificación
2.
J Therm Biol ; 48: 69-76, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25660633

RESUMEN

Thermodynamic study of incubated eggs is an important component in the optimisation of incubation processes. However, research on the interaction of heat and moisture transfer mechanisms in eggs is rather limited and does not focus on the hatching stage of incubation. During hatch, both the recently hatched chick and the broken eggshell add extra heat and moisture contents to the hatcher environment. In this study, we have proposed a novel way to estimate thermodynamically the amount of water evaporated from a broken eggshell during hatch. The hypothesis of this study considers that previously reported drops in eggshell temperature during hatching of chicks is the result remaining water content evaporating from the eggshell, released on the inner membrane by the recently hatched wet chick, just before hatch. To reproduce this process, water was sprayed on eggshells to mimic the water-fluid from the wet body of a chick. For each sample of eggshell, the shell geometry and weight, surface area and eggshell temperature were measured. Water evaporation losses and convection coefficient were calculated using a novel model approach considering the simultaneous heat and mass transfer profiles in an eggshell. The calculated average convective coefficient was 23.9 ± 7.5 W/m(2) °C, similar to previously reported coefficients in literature as a function of 0.5-1m/s air speed range. Comparison between measured and calculated values for the water evaporation showed 68% probability accuracy, associated to the use of an experimentally derived single heat transfer coefficient. The results support our proposed modelling approach of heat and mass transfer mechanisms. Furthermore, by estimating the amount of evaporated water in an eggshell post-hatch, air humidity levels inside the hatcher can be optimised to ensure wet chicks dry properly while not dehydrating early hatching chicks.


Asunto(s)
Animales Recién Nacidos/fisiología , Pollos/fisiología , Modelos Teóricos , Animales , Huevos , Calor , Humedad , Temperatura , Termodinámica , Agua
3.
Poult Sci ; 92(3): 620-8, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23436512

RESUMEN

Embryonic growth and development is influenced by both endogenous and exogenous factors. The purpose of this review is to discuss the critical stages of chick embryonic development in relation to functional maturation of numerous organ systems, the acquisition of thermoregulation, and the hatching process. In addition, the mechanism of hatching, including sound synchronization and hormonal and environmental stimulation, will be discussed. Finally, the importance of effective hatching synchronization mechanisms will also be highlighted.


Asunto(s)
Embrión de Pollo/crecimiento & desarrollo , Pollos/fisiología , Animales , Factores de Tiempo
4.
Anim Genet ; 43(3): 324-7, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22486505

RESUMEN

Enterotoxigenic Escherichia coli (ETEC) is one of the most frequently isolated enteropathogens in production animals, especially pigs and calves. Economically, the swine industry is by far the most affected by infections with ETEC because of mortality, morbidity and decreased growth rate of newborn and early-weaned piglets. After ingestion by the animal, these bacteria attach themselves to specific receptors on the small intestinal epithelium by means of proteinaceous surface appendages, the fimbriae. The F4 fimbriae, which attach to the F4 receptor, are the most studied. The aim of our study was to investigate gene expression in the small intestine of piglets of MUC13 and MUC20 in relation to animals with a different treatment towards or a different reaction on ETEC-F4ac by means of quantitative reverse transcription chain reaction (qRT/PCR). MUC13 and MUC20 are positional candidate genes for this F4ac receptor and are located in the region on SSC13q41 that segregates with the susceptibility to ETEC-F4ac. The condition of the small intestine is crucial when examining expression differences between different samples. Therefore, the expression of two genes, fatty-acid binding protein 2, intestinal (FABP2) and pancreatitis-associated protein (PAP), now known as regenerating islet-derived 3 alpha (REG3A) in the small intestine was simultaneously checked. FABP2, a standard for epithelial content, reflects the state of damage, whereas REG3A is a measure for inflammation in the small intestine. The four different substudies presented here suggest that expression of MUC13 and MUC20 is not related to the susceptibility of piglets to ETEC-F4ac.


Asunto(s)
Escherichia coli Enterotoxigénica/fisiología , Infecciones por Escherichia coli/veterinaria , Intestino Delgado/metabolismo , Mucinas/metabolismo , Enfermedades de los Porcinos/genética , Animales , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Susceptibilidad a Enfermedades/inmunología , Susceptibilidad a Enfermedades/veterinaria , Infecciones por Escherichia coli/genética , Infecciones por Escherichia coli/inmunología , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Expresión Génica , Regulación de la Expresión Génica , Mucosa Intestinal/inmunología , Mucosa Intestinal/metabolismo , Intestino Delgado/inmunología , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Mucinas/genética , Proteínas Asociadas a Pancreatitis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Porcinos , Enfermedades de los Porcinos/inmunología
5.
Acta Chir Belg ; 110(3): 332-4, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20690517

RESUMEN

Aneurysm of the splenic artery which arises from the superior mesenteric artery is a very rare condition with less than twenty cases described in the literature. Most of the time, it is asymptomatic and the diagnosis is fortuitous, but the patient can feel epigastric or left upper quadrant discomfort. One can palpate an abdominal mass or hear an abdominal systolic murmur. The most fatal presentation is the life-threatening rupture. We report the case of a 41-year-old woman presenting an aneurysm of the splenic artery originating from the superior mesenteric artery treated surgically by simple aneurismal resection with neither arterial reconstruction nor splenectomy. The different treatment modalities are discussed, taking into account the presence of the vascular malformation.


Asunto(s)
Aneurisma/cirugía , Arteria Esplénica/anomalías , Arteria Esplénica/cirugía , Dolor Abdominal/etiología , Adulto , Aneurisma/diagnóstico por imagen , Femenino , Humanos , Imagenología Tridimensional , Ligadura , Arteria Esplénica/diagnóstico por imagen , Tomografía Computarizada por Rayos X
6.
B-ENT ; 5(2): 65-72, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19670592

RESUMEN

OBJECTIVES: To assess the presence of middle ear pathogens in nasopharynx (NP), middle ear fluid (MEF), and middle ear mucosal swabs (MES) of 14 patients undergoing middle ear surgery. METHODOLOGY: Bacteria were assessed by culture and species specific PCR. Biofilm was investigated by confocal laser scanning microscopy (CLSM) of middle ear biopsies (MEBs). RESULTS: Bacteria were absent in CLSM of MEBs in three of the four closed and healthy middle ears. Bacteria occurred in the ear with a foreign body (middle ear prosthesis), which showed localized living and dead bacteria, indicating biofilm. Bacterial growth was present in ten patient ears, but biofilm occurred in only one patient. CLSM indicated biofilm in the middle ear of two patients for whom PCR detected Haemophilus influenzae in the MEF. The three classical pathogens could frequently be found in the nasopharynx, by culture and PCR, but not from the middle ear. Alloiococcus otitidis was detected in the MEF of all five patients with open inflamed ears, though virtually absent from the nasopharynx. Pseudomonas aeruginosa was present in seven. It was the only pathogen found on several occasions in all three locations in one patient. CONCLUSIONS: This study confirms the association of H. influenzae with middle ear biofilm, and indicates a potential role of P. aeruginosa in middle ear inflammation and biofilm formation. Biofilm does not seem to cause inflammation. It is unclear whether the predominance of A. otitidis in chronically inflamed open middle ears indicates a pathogenic or contaminant role for this organism.


Asunto(s)
Biopelículas , Bacterias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/aislamiento & purificación , Otitis Media/microbiología , Otitis Media/patología , Adolescente , Adulto , Estudios de Casos y Controles , Niño , Estudios de Cohortes , Exudados y Transudados/microbiología , Humanos , Microscopía Confocal , Persona de Mediana Edad , Nasofaringe/microbiología , Reacción en Cadena de la Polimerasa , Mucosa Respiratoria/microbiología , Adulto Joven
7.
Animal ; 12(4): 765-773, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28835293

RESUMEN

This study was conducted to evaluate the effect of a 12-h light, 12-h dark (12L : 12D) photoperiod of green light during day 1 to day 18 of incubation time, on embryo growth, hormone concentration and the hatch process. In the test group, monochromatic light was provided by a total of 204 green light-emitting diodes (522 nm) mounted in a frame which was placed above the top tray of eggs to give even spread of illumination. No light-dark cycle was used in the control group. Four batches of eggs (n=300/group per batch) from fertile Ross 308 broiler breeders were used in this experiment. The beak length and crown-rump length of embryos incubated under green light were significantly longer than that of control embryos at day 10 and day 12, respectively (P<0.01). Furthermore, green light-exposed embryos had a longer third toe length compared with control embryos at day 10, day 14 and day 17 (P=0.02). At group level (n=4 batches), light stimulation had no effect on chick weight and quality at take-off, the initiation of hatch and hatch window. However, the individual hatching time of the light exposure focal chicks (n=33) was 3.4 h earlier (P=0.49) than the control focal chicks (n=36) probably due to the change in melatonin rhythm of the light group. The results of this study indicate that green light accelerates embryo development and alters hatch-related hormones (thyroid and corticosterone), which may result in earlier hatching.


Asunto(s)
Embrión de Pollo/crecimiento & desarrollo , Pollos/fisiología , Desarrollo Embrionario/efectos de la radiación , Fotoperiodo , Animales , Peso Corporal , Embrión de Pollo/efectos de la radiación , Ritmo Circadiano/fisiología , Corticosterona , Luz , Melatonina/metabolismo , Óvulo
8.
Acta Chir Belg ; 106(4): 423-6, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17017698

RESUMEN

Osteosarcomas of the cranial bones need a large surgical radical resection. The best option to reconstruct mandible defect after resection is the free fibula flap. In our patient an acute ischaemic leg occurred just after the free fibula flap harvest for mandible reconstruction. The abnormal distribution of the calf arteries leads to catastrophic consequences. The peroneal artery could be the main dominant artery of the leg in a small number of patients. We reported an extremely rare case of "peronea magna", described in less than 0.2% of the global population. A careful pre-operative workup of the calf vessels is required in all the patients who need free fibula flap harvest.


Asunto(s)
Trasplante Óseo , Peroné/cirugía , Complicaciones Intraoperatorias , Isquemia/etiología , Pierna/irrigación sanguínea , Mandíbula/cirugía , Procedimientos de Cirugía Plástica , Recolección de Tejidos y Órganos/efectos adversos , Adulto , Femenino , Peroné/irrigación sanguínea , Estudios de Seguimiento , Supervivencia de Injerto , Humanos , Neoplasias Mandibulares/cirugía , Necrosis , Osteosarcoma/cirugía , Arteria Poplítea/anomalías , Arterias Tibiales/anomalías
10.
Am J Cardiol ; 82(12): 1468-74, 1998 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-9874049

RESUMEN

Dipyridamole single-photon emission computed tomography (SPECT) has a high negative predictive value for perioperative cardiac events, but events are infrequent in patients with a positive test. In contrast, dipyridamole echocardiography is more selective for detection of multivessel disease and thus may have a greater specificity for cardiac events. We therefore compared the ability of dipyridamole SPECT and echocardiography to predict perioperative and long-term cardiac events in 133 patients referred for vascular surgery. The group was also evaluated based on clinical features and ejection fraction. Four patients had surgery cancelled because of high risk and were excluded from further analysis. Among the 129 remaining patients, 21 had coronary revascularization (n=12) or an early cardiac end point (n=9). The sensitivity of SPECT for the prediction of early events (90%) was not significantly different from that of echocardiography (66%, p=NS). The specificity of SPECT (68%) was less than that of echocardiography (88%, p <0.001%), as was the accuracy (72% vs 84%, p=0.02). These findings were replicated after exclusion of patients with treatment end points. During long-term follow-up, 12 patients experienced > or = 1 event: 6 died from cardiac causes, 4 underwent revascularization, and 3 had myocardial infarction. Thus, the specificity of SPECT and echocardiography for late events were 58% and 80%, respectively (p <0.001). The 3-year survival of patients without ischemia during echocardiography or at SPECT was not different (93% vs 94%, p=NS).


Asunto(s)
Enfermedad Coronaria/diagnóstico por imagen , Dipiridamol , Ecocardiografía , Prueba de Esfuerzo/métodos , Tomografía Computarizada de Emisión de Fotón Único , Vasodilatadores , Adulto , Anciano , Anciano de 80 o más Años , Ecocardiografía/métodos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Riesgo , Sensibilidad y Especificidad , Tomografía Computarizada de Emisión de Fotón Único/métodos
11.
J Thorac Cardiovasc Surg ; 99(2): 241-9; discussion 249-50, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2299861

RESUMEN

The conventional surgical treatment of isolated critical stenosis of the left main coronary artery restores a less physiologic perfusion of the myocardium, leads to occlusion of the left coronary ostium, and consumes an appreciable length of bypass material. Starting in June 1985, 23 surgical angioplasties have been performed in 22 patients. The left main stem was approached posteriorly in the first 11 patients, and an anterior approach was preferred in the last 12 because of better exposure. The onlay patch consisted of saphenous vein in the first 14 patients; pericardium was preferred in the last nine. The five failures occurred early. Four of these occurred in patients older than 60 years in whom calcifications of the left main stem had been seen on the preoperative angiogram. Eighteen procedures (78.3%) succeeded, but one patient (5.5%) died later of a massive air embolism. The 17 survivors are free of symptoms (maximal stress test combined with thallium scintigraphy) after a mean follow-up of 24.3 months. Angiographic restudy at an average of 8 months was obtained in 14 patients (82.3%) and revealed an excellent result in 13. In five patients, a late angiographic restudy (22 to 37 months) still revealed perfect patency of the left main stem. Provided that well-defined contraindications (calcifications, involvement of the distal bifurcation, older age) are respected, surgical angioplasty deserves a place in the array of surgical strategies.


Asunto(s)
Enfermedades de las Arterias Carótidas/cirugía , Adulto , Anciano , Arterias Carótidas/diagnóstico por imagen , Constricción Patológica/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Radiografía
12.
J Thorac Cardiovasc Surg ; 98(1): 80-8; discussion 88-9, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2739428

RESUMEN

Between September 1985 and November 1987, 246 sequential mammary grafts were performed in 231 consecutive patients. Seventy-eight percent had triple vessel disease, and 33% required an urgent procedure. The length of the internal mammary artery pedicle was the only limitation to its use. No account was taken of the free cut-end flow of the internal mammary artery. There were 14 bilateral sequential mammary grafts and 15 free sequential mammary grafts. Of the 531 sequential mammary anastomoses, 482 were built with the left internal mammary artery; 113 (21%) were diamond-shaped anastomoses. The right internal mammary artery was brought through the transverse sinus in 44 cases, 10 times for sequential grafting of circumflex branches. Taking into account the adjunctive venous anastomoses and the single internal mammary artery anastomoses, there were 4.5 distal anastomoses per patient, 2.8 being mammary anastomoses and 2.3 being sequential mammary anastomoses. The hospital mortality rate was 2.6%. The prevalence of perioperative myocardial infarction was 5.2%. Follow-up was complete and averaged 15.4 months. Six patients (2.7%) still had angina pectoris. One hundred fifty-seven (71%) patients were recatheterized 6 months after the operation, and 95% of the sequential mammary anastomoses were still patent. The patency rate of the diamond-shaped mammary anastomoses was 94.5% and that of the anastomoses corresponding to the right internal mammary arteries brought through the transverse sinus was 94.3%. The gratifying functional results (maximal stress test combined with exercise thallium scintigraphy) obtained at an average of 6 months postoperatively illustrated the surprising physiologic adaptability of the internal mammary artery. As the attrition rate of the mammary artery grafts beyond 6 months postoperatively is thought to be minimal, gratifying long-term results with widespread use of sequential mammary grafts can be anticipated.


Asunto(s)
Enfermedad Coronaria/cirugía , Anastomosis Interna Mamario-Coronaria/métodos , Arterias Mamarias/trasplante , Arterias Torácicas/trasplante , Adulto , Anciano , Angina de Pecho/etiología , Enfermedad Coronaria/mortalidad , Enfermedad Coronaria/fisiopatología , Disnea/etiología , Electrocardiografía , Prueba de Esfuerzo , Femenino , Estudios de Seguimiento , Humanos , Masculino , Arterias Mamarias/diagnóstico por imagen , Persona de Mediana Edad , Complicaciones Posoperatorias , Radiografía , Reoperación , Factores de Tiempo , Grado de Desobstrucción Vascular
13.
J Thorac Cardiovasc Surg ; 103(4): 665-70, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1532220

RESUMEN

Between December 1988 and April 1991, 74 free inferior epigastric arteries were used in 73 patients for coronary artery bypass grafts. In addition, 72 of the patients received a left internal mammary artery for single or sequential grafting to the left anterior descending system and 62 a right internal mammary artery to the circumflex or the right coronary artery. Twenty-seven patients had no saphenous vein available, and two had no suitable internal mammary artery; in an attempt to make a complete arterial revascularization, we chose the inferior epigastric artery as an alternative conduit in 24 young patients and in 10 reoperations; bilateral internal mammary artery dissection was avoided in four patients with impaired lung function and in six patients with selected two-vessel disease to spare one internal mammary artery. The technique for harvesting the inferior epigastric artery is described. Fifty-three inferior epigastric artery grafts were anastomosed to the distal right coronary artery or to its branches, 18 to the distal obtuse marginals of the circumflex artery (three as sequential grafts and one as a natural Y graft), and three to the left anterior descending system. The mean number of distal anastomoses is 3.60 per patient. Seventy proximal anastomoses of the inferior epigastric artery were made to the aorta and four to one internal mammary artery. There were four early deaths and one nonfatal myocardial infarction. Four abdominal wound hematomas needed surgical drainage. Sixty-one patients underwent angiographic study on postoperative day 10:59 of 61 inferior epigastric artery grafts (63 of 65 inferior epigastric artery distal anatomoses) and 111 of 111 internal mammary artery grafts (155 of 156 internal mammary artery distal anastomoses) were patent. Clinical follow-up of all the survivors (100% follow-up) could be obtained with a mean period of 9 months (1 to 28 months). There was no late cardiac death, no infarction, and all the patients were free of angina. Nineteen patients underwent a 6-month postoperative angiographic study. Seventeen of 19 inferior epigastric artery grafts were patent and 16 of 19 were intact; 34 of 34 internal mammary artery grafts (46 of 47 internal mammary artery distal anastomoses) were patent and intact. In conclusion, free inferior epigastric artery grafts can reach the diaphragmatic ischemic areas of the heart. The early patency rate and the clinical results are encouraging but only long-term evolution and evaluation can determine the true efficacy of the inferior epigastric artery graft as a reliable conduit for coronary artery bypass graft operations.


Asunto(s)
Músculos Abdominales/irrigación sanguínea , Arterias/trasplante , Puente de Arteria Coronaria/métodos , Adulto , Anciano , Anastomosis Quirúrgica , Femenino , Humanos , Anastomosis Interna Mamario-Coronaria , Masculino , Persona de Mediana Edad
14.
J Thorac Cardiovasc Surg ; 122(2): 296-304, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11479502

RESUMEN

OBJECTIVE: Recently we reviewed the 10-year clinical and angiographic outcomes of sequential internal thoracic artery grafting. Most of the patients also received complementary saphenous grafts, and their overall long-term patency rates were surprisingly high. Therefore, we decided to analyze these results in more detail. METHODS: The first consecutive 500 patients having received at least one sequential internal thoracic artery graft between October 1985 and August 1991 were restudied retrospectively. The saphenous grafts were only used to achieve complete revascularization in addition to complex arterial grafting on less significant or remote coronary vessels. A total of 161 patients consented to a late angiographic restudy at a mean postoperative interval of 7.5 years (1-12.2 years). RESULTS: At 5 and 10 years postoperatively, freedom from angina was 96% and 82%, and freedom from any cardiac event was 92.8% and 69%, respectively. Only 15 (3.1%) patients needed additional revascularization (0.3% per patient-year): 4 coronary artery bypass grafting (0.8%) and 11 percutaneous transluminal coronary angioplasty (2.3%). The overall patency and intactness rates of saphenous anastomoses were 72.5% and 60.2%, respectively. There was a significant difference between the patency and intactness of sequential versus single anastomoses: 76% versus 60% and 64.5% versus 44.4%, respectively. There was no significant difference in either patency or intactness between right internal thoracic and sequential saphenous grafts anastomosed to the right coronary artery: 83.4% versus 75.2% and 77.8% versus 62.4%, respectively. The same was true for the anastomoses to the "remote area" (distal circumflex, distal right coronary artery). CONCLUSIONS: Complementary sequential saphenous grafting still deserves consideration in some patients below 70 years of age, particularly for those with disease in the "remote area": the distal circumflex and right coronary branches.


Asunto(s)
Vena Safena/trasplante , Arterias Torácicas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Anastomosis Quirúrgica , Angiografía Coronaria , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/cirugía , Femenino , Estudios de Seguimiento , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Reoperación/estadística & datos numéricos , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento , Grado de Desobstrucción Vascular
15.
FEMS Microbiol Lett ; 115(2-3): 335-9, 1994 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-8138145

RESUMEN

To study the effect of plasmids on the arbitrary primer-polymerase chain reaction fingerprint of bacterial strains, the Escherichia coli strains DH5, Top10, and W3110 were transformed with plasmids of different sizes: respectively, pUC19, pCEP and two clinically important plasmids carrying resistance to several antibiotics. Total DNA, i.e. both chromosomal and plasmid DNA, was prepared from transformed cells by boiling the cell suspensions and by phenol-chloroform extraction; chromosomal DNA was prepared by the same methods from the non-transformed, plasmid-free strains; plasmid DNA of pUC19 was purchased; plasmid DNA of pCEP was purified from the transformed strains by caesium chloride density gradient centrifugation. Arbitrarily primed polymerase chain reaction was carried out for all of these preparations. Amplification carried out independently with three different primers resulted in similar patterns for the chromosomal preparations whether or not plasmid was present. Amplification of plasmid DNA gave different patterns, characterized by fragments larger than those obtained when total or chromosomal DNA were used as the target. These data illustrate that the plasmids studied here do not influence the chromosomal arbitrarily primed PCR fingerprint, although plasmids alone are amplified in the absence of chromosomal DNA. Experiments comparing different relative concentrations of plasmid and chromosomal DNA indicate that under natural conditions the amount of chromosomal DNA per cell is sufficient to inhibit observable amplification of the plasmid(s) present.


Asunto(s)
Dermatoglifia del ADN/métodos , Cartilla de ADN , Escherichia coli/genética , Plásmidos/genética , Reacción en Cadena de la Polimerasa/métodos , Secuencia de Bases , Variación Genética , Datos de Secuencia Molecular
16.
Ann Thorac Surg ; 56(4): 975-7, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8215681

RESUMEN

The right gastroepiploic artery is currently regarded as a most valuable arterial conduit for myocardial revascularization. We have documented a particular case wherein the proximal (pyloric) part of the right gastroepiploic artery could not be freed and was damaged because of previous cholecystectomy. The pedicle was divided at the pyloric side and raised up to be anastomosed to the posterior descending artery in a retrograde fashion. The purpose of this report is to emphasize the fact that a previous abdominal operation does not necessarily hamper the use of the gastroepiploic artery as a pedicled graft. It is also pointed out that retrograde flow in the pedicle was sufficient in this case to provide good revascularization.


Asunto(s)
Revascularización Miocárdica/métodos , Estómago/irrigación sanguínea , Arterias/trasplante , Colecistectomía , Humanos , Masculino , Persona de Mediana Edad
17.
Ann Thorac Surg ; 67(6): 1943-6; discussion 1953-8, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10391345

RESUMEN

BACKGROUND: We evaluate the efficiency of multilevel somatosensory evoked potential (SEP) monitoring for intraoperative re-establishment of blood flow to the spinal cord in 63 patients undergoing descending aorta repair. METHODS: The presence of critical vessels in a cross-clamped aortic segment was ascertained by a 15 minute SEP observation period while the segment between the clamps was vented to drain out the collateral flow. RESULTS: SEPs influenced the surgical strategy in 17 cases (27%): use of the Biomedicus in 1 traumatic rupture; critical vessel reimplantation or distal clamp replacement in 13 cases of segmental spinal ischemia; and hastening the procedure or proximal clamp replacement in 3 cases of left carotid ischemia. There were no cases of unexplained multilevel SEP abnormalities. Immediate paraplegia was observed in 2 cases (1 pre-existing; 1 forecast by a 199-minute period of SEP absence due to segmental ischemia); 2 patients presented delayed paraplegias despite unchanged intraoperative SEPs, and 1 case presented a transient paraplegia due to lower motoneuronal involvement. CONCLUSIONS: SEPs efficiently identified critical vessels to be reimplanted in order to avoid immediate paraplegia. However, systematic additional vessel reimplantation, if technically feasible, and prolongation of SEP monitoring during the postoperative period with careful blood pressure control are needed to prevent delayed paraplegia.


Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Potenciales Evocados Somatosensoriales , Isquemia/prevención & control , Monitoreo Intraoperatorio , Complicaciones Posoperatorias/prevención & control , Médula Espinal/irrigación sanguínea , Adulto , Constricción , Humanos , Persona de Mediana Edad , Paraplejía/prevención & control , Flujo Sanguíneo Regional , Sensibilidad y Especificidad , Resultado del Tratamiento
18.
J Virol Methods ; 60(2): 155-9, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8844621

RESUMEN

The efficacy of eight different methods for the extraction of HIV-1 RNA from plasma was compared. The RNA preparation method that gave the best results by RT-PCR was the one described by Chomczynski and Sacchi (1987, Anal. Biochem. 162, 156-159). This method consists of a guanidine thiocyanate treatment followed by three phenol-chloroform-isoamylalcohol extractions and an ethanol precipitation. The disadvantage of this method is that it is time consuming and less suitable for the extraction of large series of samples. Moreover, due to the large number of procedural steps, there is a greater risk of sample mix-up or contamination. Of the single-step RNA purification methods, good results were obtained with the TRIzol method (Gibco Life Technologies, Paisley, UK) and with the extraction method offered by the NASBA kit (Organon Teknika, Turnhout, Belgium). The above single-step methods are recommended since both are sensitive enough to detect low copy numbers of HIV-RNA in the plasma of asymptomatic patients, and require only 2 h for completion. For most of the methods evaluated the inter-test variability was acceptable (mean variation coefficient between duplicate extraction varied between 17.3 and 47.3%). Inter-laboratory reproducibility was evaluated only for the TRIzol-method and found to be low (mean variation coefficient 63.4).


Asunto(s)
Infecciones por VIH/virología , VIH-1/aislamiento & purificación , ARN Viral/sangre , ARN Viral/aislamiento & purificación , Carga Viral/métodos , Estudios de Evaluación como Asunto , VIH-1/genética , Humanos , Reacción en Cadena de la Polimerasa , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Viremia/virología
19.
J Heart Valve Dis ; 9(1): 75-80; discussion 81, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10678378

RESUMEN

BACKGROUND AND AIM OF THE STUDY: Repair of the prolapsing anterior leaflet (AML) in degenerative mitral valve disease is more demanding than that of the posterior leaflet. We reviewed our experience in the past eight years, to examine the safety, efficacy and stability of various repair artifices. METHODS: Between January 1989 and December 1997, 102 patients (mean age 64 years; range: 26-86 years) with mitral regurgitation (MR) due to prolapse of the anterior or both mitral leaflets underwent mitral valve repair. Sixty-six patients were in NYHA class > or =III, and 94 had MR grade >II. Acute endocarditis was present in 12 patients and Barlow disease in 16. Surgical techniques consisted of chordal shortening (n = 36), chordal transposition (n = 16), papillary muscle shortening or plication (n = 10), flip-over (n = 20) and artificial chordae implantation (n = 20). RESULTS: There was no early mortality; one patient required early mitral valve replacement (MVR) for late-appearing systolic anterior motion, and one patient benefited from a successful re-repair on day 8 for partial posterior leaflet desinsertion. Mean follow up was 30 months (range: 3-92 months); there were four late deaths (two valve-related cerebrovascular accidents); two patients required re-repair (one after three months for prosthetic ring thrombosis, and one after 10 months for rupture of shortened chordae (corrected by flip-over)). Five patients had MVR between four and 32 months later: one for mitral stenosis due to posterior leaflet calcification, and four for recurrent MR due to the rupture of shortened chordae (n = 3) or plicated papillary muscle (n = 1). One patient suffered bacterial endocarditis which was treated medically. Of the 92 remaining patients with valve repair, 81 are currently asymptomatic, five are in NYHA class II and four in class III. Transesophageal echocardiographic restudy (n = 76) at a mean of 30 months after surgery revealed no MR in 68 patients, and MR of grade

Asunto(s)
Prolapso de la Válvula Mitral/cirugía , Anciano , Anciano de 80 o más Años , Cuerdas Tendinosas/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Politetrafluoroetileno , Complicaciones Posoperatorias , Estudios Retrospectivos , Resultado del Tratamiento
20.
J Heart Valve Dis ; 9(3): 350-2, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10888089

RESUMEN

BACKGROUND AND AIM OF THE STUDY: Coverage of large commissural defects may present a surgical challenge in mitral valve repair, for which the transfer of posterior tricuspid valve leaflet tissue is an attractive approach. METHODS: Five patients aged between 35 and 55 years underwent this procedure. After wide excision of the diseased mitral commissures, the posterior leaflet of the tricuspid valve was carefully checked, removed with its subvalvular apparatus, and transferred to the commissural area of the mitral valve. The stress on the papillary muscle suture was relieved by reinforcement of the free edge of the transferred leaflet by natural or artificial chordae. The tricuspid valve was repaired using either a sliding plasty or an annuloplasty. RESULTS: One patient who had no reinforcement of the subvalvular apparatus had a papillary muscle rupture and required mitral valve replacement during the early postoperative period. The four remaining patients remained asymptomatic and had no or trivial mitral regurgitation after a median of 13 months (range: 3-18 months), with excellent result at transesophageal echocardiography. CONCLUSION: We conclude that transfer of the tricuspid valve leaflet allows coverage of large commissural defect, and deserves a place among the surgeon's arsenal of reconstructive techniques for mitral valve repair.


Asunto(s)
Endocarditis Bacteriana/cirugía , Estenosis de la Válvula Mitral/cirugía , Válvula Mitral/cirugía , Válvula Tricúspide/trasplante , Adulto , Cuerdas Tendinosas/trasplante , Humanos , Persona de Mediana Edad , Politetrafluoroetileno , Suturas , Válvula Tricúspide/cirugía
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