Manifestaciones cutáneas asociadas a enfermedad inflamatoria intestinal pediátrica. Serie de casos / Cutaneous manifestations associated with paediatric inflammatory bowel disease. Case series

Introducción. Las manifestaciones extraintestinales en la enfermedad inflamatoria intestinal tienen una prevalencia variable de 6 a 47%, dentro de las cuales las manifestaciones cutáneas en la edad pediátrica suponen un 10-15%, siendo las más frecuentes el pioderma gangrenoso y el eritema nodoso. Suelen presentar una adecuada evolución clínica, a pesar de ello es importante realizar un correcto diagnóstico con tratamiento precoz. Presentamos tres casos clínicos de enfermedad inflamatoria intestinal con manifestaciones dermatológicas asociadas. Caso 1. Vasculitis leucocitoclástica asociada a colitis ulcerosa en paciente varón de 11 años. Presenta buena respuesta al tratamiento con corticoterapia e inmunosupresores. Caso 2. Varón de 8 años con eritema nodoso asociado a enfermedad de Crohn. Buena respuesta clínica con nutrición enteral exclusiva e inmunosupresores. Caso 3. Mujer 15 años con psoriasis en gotas asociada a tratamiento con anti-TNF en enfermedad de Crohn. Resolución tras retirada de agente desencadenante. Conclusiones. Las manifestaciones dermatológicas en la edad pediátrica son menos frecuentes que en adultos. De manera habitual tienen un curso leve y autolimitado como es el caso de nuestros dos primeros pacientes. El tercer caso lo presentamos como causa de manifestación cutánea secundaria a tratamiento de mantenimiento de la enfermedad de base (AU)

Introduction. Extraintestinal manifestations in inflammatory bowel disease have a variable prevalence of 6-47%, within which cutaneous manifestations in pediatric age account for 10-15%, the most frequent being pyoderma gangrenosum and erythema nodosum. They usually present an adequate clinical evolution, in spite of this it is important to make a correct diagnosis with early treatment. Our objective is to present three clinical cases of dermatologic manifestations of inflammatory bowel disease from our practice. Case 1. Leukocytoclastic vasculitis associated with ulcerative colitis in an 11-year-old male patient. He presented good response to treatment with corticotherapy and immunomodulator. Case 2. 8-year-old male with erythema nodosum associated with Crohn´s disease. Good clinical response with exclusive enteral nutrition and immunomodulator. Case 3. 15-year-old woman with guttate psoriasis associated with anti-TNF treatment for Crohn´s disease. Resolution after withdrawal of the triggering agent. Conclusions. Dermatological manifestations in pediatric age are less frequent than in adults. They usually have a mild and self-limited course as in the case of our first two patients. The third case is presented as a cause of cutaneous manifestation secondary to maintenance treatment of the underlying disease (AU)

Airplane cabin waste characterization: Knowing the waste for sustainable management and future recommendations.

The aviation industry generates a significant amount of comingle waste. Nowadays, companies are making efforts to enhance waste management and reduce waste generation. In order to improve present practices and implement a proper waste management system, the quantities, materials, and typology of waste generated need to be studied. A total of 145 airplanes were analysed. We differentiated 5 strips of duration and identified 4 different generation sources within the cabin associated to the business and tourist passenger classes. We classified and characterized the waste into 20 different materials. Results provide a detailed, representative and adapted study of the catering waste generated in the aviation industry. The characterization, which allows distinguishing between manipulated and unmanipulated materials, aims at providing useful information to reduce the generation of waste. The analysis performed in the present study shows that the flying distance increases the waste generation, as more food is served. It also shows that organic matter, paper/cardboard and packaging are the dominant materials in the waste generated in flights. The results of the characterizations obtained allow making some recommendations. The use of bi-compartmentalized waste trolleys to separate on-board recyclable materials from the rest is desirable to obtain a clean recoverable waste stream. Supressing unpopular food from menus, identified analysing the leftovers, could also reduce the amount of waste generated. (This characterization study is part of the European project LIFE + Zero Cabin Waste.). Changes in the CE 1069/2009 regulation would allow more waste to be recycled instead of landfilled. Ultimately, the information obtained from this study will be used to design a more sustainable waste management system.

Absceso masivo de pared abdominal por diverticulitis aguda evolucionada / Massive abscess in abdominal wall due to complicated diverticulitis

La mayoría de los pacientes con divertículos de colon no presentan complicaciones y, en caso de presentarlas, suelen ser intraabdominales. Exponemos el caso de un varón de 52 años que consultó en el Servicio de Urgencias por dolor abdominal de 3 semanas de evolución asociado a tumoración infraumbilical con signos de flogosis. La analítica sanguínea mostró leucocitosis importante con desviación izquierda y elevación de la proteína C reactiva. La tomografía computarizada evidenció un gran absceso de pared abdominal que comunicaba con cambios inflamatorios en sigma ("en reloj de arena"). Se decidió intervenir de forma quirúrgica urgente hallando diverticulitis aguda de sigma muy evolucionada. Se realizó drenaje y colostomía en cañón de escopeta sobre varilla. El absceso de pared abdominal como debut de diverticulitis aguda complicada es una forma de presentación muy infrecuente de esta patología, existiendo pocos antecedentes descritos en la literatura al respecto

The majority of patients with diverticula have not any complications. If they appear, they use to present as an intra-abdominal complication. We present the case of a 52-year-old man who came to the Emergency Service with lower abdominal pain for 3 weeks and a visible mass with inflammatory signs in this site. The blood test showed a marked leucocytosis with neutrophilia and the compute tomography revealed an abscess of the abdominal wall related with inflammatory changes in sigmoid colon ("hourglass"). We decided emergency surgery and we found evolved acute sigmoid diverticulitis. Local drainage of the abscess and loop colostomy opened over a rod were performed. The abdominal wall abscess as a form of debut of acute complicated diverticulitis is a very uncommon presentation of this pathology. There are few antecedents in the literature about this matter

MC1R polymorphism associated with plumage color variations in Coturnix chinensis.

The melanocortin 1 receptor (MC1R) gene was investigated as a candidate for plumage variations in Chinese painted quail, Coturnix chinensis. Four silent and two missense nucleotide polymorphisms were identified. The correspondent amino acid changes, p.Glu92Lys and p.Pro292Leu, were found in Blue Face and Red Breasted animals respectively. Blue Face is a melanic phenotype similar to the co-dominant Extended Brown of Japanese quail, and both share the p.Glu92Lys mutation. The association of p.Pro292Leu with the recessive Red Breasted was confirmed in 23 animals from an experimental F2 cross.

Development and validation of a Bayesian network for the differential diagnosis of anterior uveitis.

PurposeTo develop and validate a Bayesian belief network algorithm for the differential diagnosis of anterior uveitis.Patients and methodsThe 11 most common etiologies were included (idiopathic, ankylosing spondylitis, psoriasic arthritis, reactive arthritis, inflammatory bowel diseases, sarcoidosis, tuberculosis, Behçet, Posner-Schlossman syndrome, juvenile idiopathic arthritis (JIA), and Fuchs' heterochromic cyclitis). Frequencies of association between factors and etiologies were retrieved from a systematic review of the literature. Prevalences were calculated using a random sample of 200 patients receiving a diagnosis of anterior uveitis in Moorfields Eye Hospital in 2012. The network was validated in a random sample of 200 patients receiving a diagnosis of anterior uveitis in the same hospital in 2013 plus 10 extra cases of the most rare etiologies (JIA, Behçet, and psoriasic arthritis).ResultsIn 63.8% of patients the most probable etiology by the algorithm matched the senior clinician diagnosis. In 80.5% of patients the clinician diagnosis matched the first or second most probable results by the algorithm. Taking into account only the most probable diagnosis by the algorithm, sensitivities for each etiology ranged from 100% (7 of 7 patients with reactive arthritis and 5 of 5 with Behçet correctly classified) to 46.7% (7 of 15 patients with tuberculosis-related uveitis). Specificities ranged from 88.8% for sarcoidosis to 99.5% in Posner.ConclusionsThis algorithm could help clinicians with the differential diagnosis of anterior uveitis. In addition, it could help with the selection of the diagnostic tests performed.

Otsc clip lost in abdomen 3 years

OTSC is a safe and effective endoscopic method used in the treatment of gastrocutaneous or esophageal fistulas. The authors describe a clinic case which an intraabdominal clip was found 3 years after she was managed with an over-the-scope-clip (OTSC) to repair a gastrocutaneous fistula.In this case, the abdominal pain could be related to a self-limited localized peritonitis that resolved without the need of any medical treatment. Efficacy and safety of over-the-scope clip, including complications after endoscopic submucosal dissection are discussed

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Newborns with lower levels of circulating polyunsaturated fatty acids (PUFA) are abdominally more adipose.

BACKGROUND: Maternal nutrition is the main source of Poly-Unsaturated Fatty Acids (PUFA) for the fetus. PUFA may influence the accumulation of fat in early life. OBJECTIVES & METHODS: In 33 breastfed infants born appropriate-for-gestational-age, we studied whether body composition (judged by absorptiometry at 2 wk and 4 mo) relates to PUFA levels (assessed by gas chromatography) in the maternal or fetal circulation at birth. RESULTS: Abdominal fat at 2 wk associated negatively to umbilical-cord levels of separate PUFA (linoleic, arachidonic, eicosapentanoic and docosahexaenoic acid; all P between 0.001 and 0.015). Collectively, the assessed n-6 PUFA on one hand and the n-3 PUFA on the other hand associated negatively to the absolute amount of abdominal fat (in grams; P = 0.001 and P = 0.002, respectively) and to the relative amount of abdominal fat (fraction of total fat; P = 0.001 and P = 0.006, respectively). No other significant associations were observed. CONCLUSION: In conclusion, newborns with lower levels of circulating PUFA were found to be abdominally more adipose. The mechanisms underpinning these associations remain to be determined.

Melanism in guinea fowl (Numida meleagris) is associated with a deletion of Phenylalanine-256 in the MC1R gene.

We have characterized a deletion in the MC1R gene causing the loss of one amino acid (p.Phe256del), which is perfectly associated with melanism in guinea fowl (Numida meleagris). Co-segregation of the p.Phe256del with melanism was confirmed in 25 offspring born from a cross of two heterozygote birds; therefore we suggest that this mutation is responsible for the black phenotype. Interestingly, this is the first case of recessive melanism linked to MC1R.

Harmonisation of ethics committees' practice in 10 European countries.

BACKGROUND: The Directive 2001/20/EC was an important first step towards consistency in the requirements and processes for clinical trials across Europe. However, by applying the same rules to all types of drug trials and transposing the Directive's principles into pre-existing national legislations, the Directive somewhat failed to meet its facilitation and harmonization targets. In the field of ethics, the Directive 2001/20/EC conditioned the way of understanding and transposing the "single opinion" process in each country. This led to a situation in which two models of research ethics committees organisation systems exist, being the model in which the "single opinion" is considered to be the decision made by a single ethics committee more effective and simpler in terms of administrative and logistic workload. METHOD: A survey was conducted in 10 European countries. Members of the European Clinical Research Infrastructures Network working party number 1, with expertise in the field of ethics, responded. RESULTS: There is a major heterogeneity in the composition of ethics committees among the surveyed countries based on the number of members, proportion of experts versus lay members and expertise of the scientific members. A harmonized education of the ethics committees' membership based in common curricula is recommended by the majority of countries. CONCLUSIONS: Despite the efforts for harmonization of the European Clinical Trial Directive, from an ethical point of view, there remains a plurality of ethics committees' systems in Europe. It is important to comprehend the individual national systems to understand the problems they are facing.

Immune reconstitution after cord blood transplants supported by coinfusion of mobilized hematopoietic stem cells from a third party donor.

Low severity of GVHD, substantial graft vs tumor (GVT) and slow development of protective immunity are well-documented features of cord blood transplants (CBT). We have evaluated the immune reconstitution of adult recipients of single-unit CBT supported by the coinfusion of third party donor (TPD) mobilized hematopoietic stem cells (MHSC), a procedure-'dual CB/TPD-MHSC transplant'-that results in early recovery of circulating granulocytes, high rates of CB engraftment and full chimerism. Cumulative recovery of natural killer and B cells at or above the median values of normal controls were 1.0 and 0.76 by the sixth and ninth months. Recovery of T cells was much slower, naive cells lagging behind those of memory and effector (committed) immunophenotypes. Serial analyses of signal joint TCR excision circles showed a general pattern of very low levels by the third month after CBT, followed by recovery to levels persistently similar or higher than those observed before transplantation and in normal controls. Our results are consistent with the clinical observations of substantial GVT effect together with low incidence of serious GVHD and slow development of protective immunity and suggest that thymic function contributes substantially to the recovery of T-cell populations in adults receiving dual CB/TPD-MHSC transplants.

The restorative effects of pulsed infrared light therapy on significant loss of peripheral protective sensation in patients with long-term type 1 and type 2 diabetes mellitus.

Pulsed infrared light therapy (PILT) has been shown to increase peripheral sensation in diabetic patients with diabetic peripheral neuropathy (DPN). However, most studies last for very short periods, with the subjects receiving only 6-20 treatments. The purpose of this study was to evaluate the effectiveness of an eight-week course of PILT in reversing long-standing, profound DPN in patients with type 1 and type 2 diabetes. Twenty-two subjects with a diagnosis of type 1 (n=2) or type 2 (n=20) diabetes participated in the study. PILT was administered to one foot chosen at random with the other foot serving as a within-subject control (no treatment). Patients underwent 24 treatments (3 times/week, for eight weeks) for 30 min per treatment. Changes in peripheral protective sensation (PPS) were measured using Semmes-Weinstein monofilaments (SWM) ranging from 3.7 to 6.48. PILT improved PPS even in patients with long-standing chronic neuropathies whose initial pre-study sensation was not measurable with a 200-g SWM. PILT significantly improves PPS. While the exact mechanism of action is not understood, infrared light may improve peripheral neuropathies by improving foot perfusion by stimulating nitric oxide production.

[Diplopia after sub-Tenon's anesthesia for cataract surgery]. / Diplopía postcirugía de catarata con anestesia subtenoniana.

PURPOSE: To study the clinical signs, treatment and prognosis of strabismus after sub-Tenon's anesthesia for cataract surgery. METHODS: Eight patients without previous strabismus developed incomitant diplopia immediately after cataract surgery; the left eye was affected in five patients and the right eye in three. Restrictive strabismus was diagnosed with the cover test, prisms, and active and passive ductions in all cases. In seven cases the deviation was vertical and in one patient it was horizontal. The average deviation was 17.5 S.D. 9.84 (range 5-35) prismatic dioptres in primary position. The deviation increased looking upward in seven cases, and looking sideways to the left in the other. It was considered to be a good result if the diplopia disappeared after treatment. RESULTS: Botulinum toxin was the first treatment applied in four patients, but only one showed a good response and required no further therapy. Strabismus surgery was required in four cases, and prisms were adapted in three. Three patients required two strabismus operations. A good result was achieved in all cases, with the average time interval being 10.12 (SD 5.5) months. CONCLUSIONS: Sub-Tenon's anesthesia may result in restrictive strabismus and incomitant diplopia which does not resolve spontaneously. The inferior rectus is the most commonly affected muscle. Strabismus surgery is required to resolve the diplopia in half of the cases. Good results have been achieved in all patients.

Diplopía postcirugía de catarata con anestesia subtenoniana / Diplopia after sub-tenon's anesthesia por cataract surgery

Objetivo: Estudiar las características del estrabismosecundario a la cirugía de catarata con anestesiasubtenoniana; su tratamiento y pronóstico.Método: Ocho enfermos sin estrabismo previo presentarondiplopía inmediatamente después de lacirugía de catarata; cinco de ojo izquierdo, tres deojo derecho. La exploración con cover test, prismasy ducción activa y pasiva mostró estrabismo restrictivo:siete de componente vertical y uno horizontal.La desviación media fue de 17,5 DE: 9,84 dioptríasprismáticas (rango 5-35) en la mirada al frente. Laposición máxima de desviación fue en supraversiónen siete, y en levoversión en otro. Todos teníandiplopía invalidante. Se considera buen resultado sidesaparecía la diplopía con el tratamiento.Resultados: Cuatro casos recibieron tratamientoquirúrgico, en uno sólo se inyectó toxina botulínicay en tres se pusieron prismas. La toxina botulínicase empleó como primera opción en cuatro casos ysólo fue eficaz en un enfermo. De los cuatro casosoperados, tres necesitaron dos cirugías y un pacientesólo un tiempo quirúrgico. Se consiguió buenresultado en los ocho pacientes tratados. El tiempomedio de evolución fue de 10,12 DE: 5,46 meses. Conclusiones: La anestesia subtenoniana puedeprovocar un estrabismo restrictivo y una diplopíamuy invalidantes que no se resuelven espontáneamente.El recto inferior es el músculo más frecuentementeafectado. La cirugía muscular es necesariapara resolver el problema en la mitad de los casos.Se consiguen buenos resultados quirúrgicos

Purpose: To study the clinical signs, treatment and ;;prognosis of strabismus after sub-Tenon’s anesthesia ;;for cataract surgery. ;;Methods: Eight patients without previous strabismus ;;developed incommitant diplopia immediately ;;after cataract surgery; the left eye was affected in ;;five patients and the right eye in three. Restrictive ;;strabismus was diagnosed with the cover test, ;;prisms, and active and passive ductions in all cases. ;;In seven cases the deviation was vertical and in one ;;patient it was horizontal. The average deviation was ;;17.5 S.D. 9.84 (range 5-35) prismatic dioptres in ;;primary position. The deviation increased looking ;;upward in seven cases, and looking sideways to the ;;left in the other. It was considered to be a good ;;result if the diplopia disappeared after treatment. ;;Results: Botulinum toxin was the first treatment ;;applied in four patients, but only one showed a good ;;response and required no further therapy. Strabismus ;;surgery was required in four cases, and prisms ;;were adapted in three. Three patients required two ;;strabismus operations. A good result was achieved ;;in all cases, with the average time interval being ;;10.12 (SD 5.5) months. Conclusions: Sub-Tenon’s anesthesia may result in ;;restrictive strabismus and incommitant diplopia ;;which does not resolve spontaneously. The inferior ;;rectus is the most commonly affected muscle. Strabismus ;;surgery is required to resolve the diplopia in ;;half of the cases. Good results have been achieved ;;in all patients

Terapia multicomponente grupal del tabaquismo en Atención Primaria / No disponible

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[Parapneumonic effussion. A review of 33 cases over 6 years]. / Derrame pleural paraneumónico. Revision de 33 casos en 6 años.

UNLABELLED: The incidence of empyema thoracis in children seems to be increasing. The objective [corrected] of this study is to propose a rational initial treatment of parapneumonic effusions in order to reduce hospital stay and late-stage empyema complications. Medical records of 33 children presenting parapneumonic effusions who required any surgical therapy between 1997 and 2002 were reviewed. They were grouped as (I) successful management with chest tube, (II) successful management with intrapleural instillation of urokinase and (III) successful surgical treatment: (IIIa) thoracoscopy or (IIIb) thoracotomy. CONCLUSION: Early sonographic evaluation of parapneumonic effusions is usefull to evaluate the severity of disease and the need for surgical intervention. Thoracoscopic-assisted surgery is an effective treatment for pediatric early-stage empyema. Thoracotomy is indicated for most children with established empyema.

Derrame pleural paraneumónico. Revisión de 33 casos en 6 años / Parapneumonic effusion. A review of 33 cases over 6 years

La incidencia de derrames paraneumónicos complicados está aumentando en pediatría. El objetivo de este trabajo es establecer una pauta de manejo precoz de los niños con derrame paraneumónico desde el momento del diagnóstico, con el fin de disminuir la estancia hospitalaria y evitar las complicaciones derivadas del empiema organizado. Para ello se revisaron las historias clínicas de 33 niños con derrame paraneumónico que precisó tratamiento específico para su resolución, atendidos entre 1997 y 2000. Se dividieron en los siguientes grupos de tratamiento: (I) drenaje del derrame mediante tubo de tórax; (II) desbridamiento de la cavidad pleural con urokinasa; (III) procedimientos quirúrgicos: (IIIa) toracoscopia y (IIIb) toracotomía. Conclusiones: la ecografía torácica precoz es útil en la evaluación de la severidad del derrame y la necesidad de tratamientos más agresivos. La toracoscopia es una técnica segura y eficaz en el manejo precoz del empiema en los niños. La toracotomía está indicada para el tratamiento del empiema organizado (AU)

The incidence of empyema thoracis in children seems to be increasing. The objetive of this study is to propose a rational initial treatment of parapneumonic effusions in order to reduce hospital stay and late-stage empyema complications. Medical records of 33 children presenting parapneumonic effusions who required any surgical therapy between 1997 and 2002 were reviewed. They were grouped as (I) successful management with chest tube, (II) successful management with intrapleural instillation of urokinase and (III) successful surgical treatment: (IIIa) thoracoscopy or (IIIb) thoracotomy. CONCLUSION: Early sonographic evaluation of parapneumonic effusions is usefull to evaluate the severity of disease and the need for surgical intervention. Thoracoscopic –assisted surgery is an effective treatment for pediatric early-stage empyema. Thoracotomy is indicated for most children with established empiema (AU)

Primary retinal reattachment surgery: anatomical and functional outcome in phakic and pseudophakic eyes.

AIM: To compare the anatomical and functional success of primary scleral buckling, performed either alone or in combination with vitrectomy, for primary retinal detachment (RD) in phakic eyes and in eyes had undergone uneventful phacoemulsification and had received posterior chamber lens implantations. METHODS: A total of 243 consecutive patients were included in this retrospective, nonrandomized comparative study. In all, 165 phakic and 78 pseudophakic individuals with primary RD underwent scleral buckling alone or in combination with vitrectomy and were followed up for 6 months. Pre-, intra- and postoperative findings including anatomical success, best-corrected visual acuity (BCVA), complications, and the development of proliferative vitreoretinopathy (PVR), macular pucker, or secondary cataracts were recorded. Cases requiring more than one surgical intervention were defined having failed, although further surgical intervention might have led to success. RESULTS: At 6 months after scleral buckling alone, the anatomical success was similar in phakic (88.98%) and pseudophakic (87.65%) eyes (log rank=0.310). The corresponding results after scleral buckling with vitrectomy were 82.13 and 77.63% for phakic and pseudophakic eyes, respectively (log rank=0.799). At 6 months after scleral buckling alone, BCVA was similar in phakic and pseudophakic eyes (0.62+/-0.30 vs 0.70+/-0.29; P=0.227). Likewise, after scleral buckling with vitrectomy, BCVA did not differ significantly (P=0.322) between phakic (0.34+/-0.32) and pseudophakic eyes (0.50+/-0.27). CONCLUSION: The anatomical and functional outcome of primary retinal reattachment surgery, involving scleral buckling alone or in combination with vitrectomy, is similar in phakic and pseudophakic eyes.

Cardiac and vascular effects of diltiazem, dobutamine and amrinone, drugs used after myocardial revascularization.

Hemodynamic care during postoperative management of myocardial revascularization should include vasorelaxing drugs to insure adequate graft and coronary flow, and stimulation of stroke volume to maintain vascular perfusion pressure. We tested the cardiac (inotropic and lusitropic) and vascular (relaxant) effects of diltiazem (0.1 nM to 0.1 mM), dobutamine (10 microM to 10 mM) and amrinone (10 microM to 1 mM) on isolated rat atria and thoracic aorta, and also on isolated human saphenous vein (HSV) and human mammary artery (HMA). Dobutamine produced a maximal positive inotropic effect (+dF/dt max = 29 +/- 7%) at its ED50 for aortic relaxation (88 +/- 7 microM). Conversely, at their ED50 for aortic relaxation diltiazem depressed myocardial contractility and amrinone did not exhibit myocardial effects. In HSV and HMA contracted with 80 mM potassium, diltiazem and dobutamine (but not amrinone) had a vasorelaxant activity similar to that in rat aorta. Norepinephrine-contracted human vessels were significantly more sensitive than potassium-contracted vessels to the relaxant effect of amrinone (ED50 HMA = 15 +/- 5 microM, ED50 HSV = 72 +/- 31 microM, P < 0.05). We conclude that at concentrations still devoid of myocardial effects dobutamine and amrinone are effective dilators in graft segment vessels and rat aorta contracted by membrane depolarization. If the difference between aortic and myocardial tissue still holds in human tissues, at the appropriate concentrations these drugs should be expected to improve cardiac performance while still contributing to the maintenance of graft patency.

Cardiac and vascular effects of diltiazem, dobutamine and amrinone, drugs used after myocardial revascularization

Hemodynamic care during postoperative management of myocardial revascularization should include vasorelaxing drugs to insure adequate graft and coronary flow, and stimulation of stroke volume to maintain vascular perfusion pressure. We tested the cardiac (inotropic and lusitropic) and vascular (relaxant) effects of diltiazem (0.1 nM to 0.1 mM), dobutamine (10 æM to 10 mM) and amrinone (10 æM to 1 mM) on isolated rat atria and thoracic aorta, and also on isolated human saphenous vein (HSV) and human mammary artery (HMA). Dobutamine produced a maximal positive inotropic effect (+dF/dt max = 29 ñ 7 percent) at its ED50 for aortic relaxation (88 ñ 7 æM). Conversely, at their ED50 for aortic relaxation diltiazem depressed myocardial contractility and amrinone did not exhibit myocardial effects. In HSV and HMA contracted with 80 mM potassium, diltiazem and dobutamine (but not amrinone) had a vasorelaxant activity similar to that in rat aorta. Norepinephrine-contracted human vessels were significantly more sensitive than potassium-contracted vessels to the relaxant effect of amrinone (ED50 HMA = 15 ñ 5 æM, ED50 HSV = 72 ñ 31 æM, P < 0.05). We conclude that at concentrations still devoid of myocardial effects dobutamine and amrinone are effective dilators in graft segment vessels and rat aorta contracted by membrane depolarization. If the difference between aortic and myocardial tissue still holds in human tissues, at the appropriate concentrations these drugs should be expected to improve cardiac performance while still contributing to the maintenance of graft patency.

In situ annealing and thickening of single crystals of C294H590 observed by atomic force microscopy.

The annealing behavior of twice-folded crystals of the long-chain alkane C294H590 is examined in situ, in real time, by atomic force microscopy (AFM). AFM is capable of following processes in real time provided that the time scale is sufficiently long for several images to be collected during the process. In this paper, we focus on the temperature dependence and the thickened morphology. We are able to investigate where the thickening starts and how this depends on temperature and how melting is influenced by morphology. By following the motion of holes within the crystal, a lower limit for the rate of diffusion of crystalline polyethylene is estimated. We also focus on the substrate effect on the crystal morphology and thickening, using mica, glass, and graphite.