Diamond X-ray beam-position monitoring using signal readout at the synchrotron radiofrequency.

Single-crystal diamond is a material with great potential for the fabrication of X-ray photon beam-position monitors with submicrometre spatial resolution. Low X-ray absorption combined with radiation hardness and excellent thermal-mechanical properties make possible beam-transmissive diamond devices for monitoring synchrotron and free-electron laser X-ray beams. Tests were made using a white bending-magnet synchrotron X-ray beam at DESY to investigate the performance of a position-sensitive diamond device using radiofrequency readout electronics. The device uniformity and position response were measured in a 25 microm collimated X-ray beam with an I-Tech Libera ;Brilliance' system. This readout system was designed for position measurement and feedback control of the electron beam in the synchrotron storage ring, but, as shown here, it can also be used for accurate position readout of a quadrant-electrode single-crystal diamond sensor. The centre-of-gravity position of the F4 X-ray beam at the DORIS III synchrotron was measured with the diamond signal output digitally sampled at a rate of 130 Msample s(-1) by the Brilliance system. Narrow-band filtering and digital averaging of the position signals resulted in a measured position noise below 50 nm (r.m.s.) for a 10 Hz bandwidth.

Post-kala-azar dermal leishmaniasis with mucosal involvement in a kidney transplant recipient: treatment with liposomal amphotericin B.

Post-kala-azar dermal leishmaniasis (PKDL) is a rare clinical variant of cutaneous leishmaniasis. It is very common in the Indian subcontinent and less frequent in East Africa, but exceptional in the American and European continents. We have observed a case of PKDL in a renal transplant recipient. No systemic symptoms were present. The patient was treated with liposomal amphotericin B. We emphasize the unusual aspects of this case: the appearance of PKDL in Europe, its relationship with immunosuppression, the severe mucosal involvement and the excellent response to liposomal amphotericin B, a newly described treatment for the disease.

Leishmania and human immunodeficiency virus coinfection: the first 10 years.

Over 850 Leishmania-human immunodeficiency virus (HIV) coinfection cases have been recorded, the majority in Europe, where 7 to 17% of HIV-positive individuals with fever have amastigotes, suggesting that Leishmania-infected individuals without symptoms will express symptoms of leishmaniasis if they become immunosuppressed. However, there are indirect reasons and statistical data demonstrating that intravenous drug addiction plays a specific role in Leishmania infantum transmission: an anthroponotic cycle complementary to the zoonotic one has been suggested. Due to anergy in patients with coinfection, L. infantum dermotropic zymodemes are isolated from patient viscera and a higher L. infantum phenotypic variability is seen. Moreover, insect trypanosomatids that are currently considered nonpathogenic have been isolated from coinfected patients. HIV infection and Leishmania infection each induce important analogous immunological changes whose effects are multiplied if they occur concomitantly, such as a Th1-to-Th2 response switch; however, the consequences of the viral infection predominate. In fact, a large proportion of coinfected patients have no detectable anti-Leishmania antibodies. The microorganisms share target cells, and it has been demonstrated in vitro how L. infantum induces the expression of latent HIV-1. Bone marrow culture is the most useful diagnostic technique, but it is invasive. Blood smears and culture are good alternatives. PCR, xenodiagnosis, and circulating-antigen detection are available only in specialized laboratories. The relationship with low levels of CD4+ cells conditions the clinical presentation and evolution of disease. Most patients have visceral leishmaniasis, but asymptomatic, cutaneous, mucocutaneous, diffuse cutaneous, and post-kala-azar dermal leishmaniasis can be produced by L. infantum. The digestive and respiratory tracts are frequently parasitized. The course of coinfection is marked by a high relapse rate. There is a lack of randomized prospective treatment trials; therefore, coinfected patients are treated by conventional regimens. Prophylactic therapy is suggested to be helpful in preventing relapses.

Variability of Leishmania (Leishmania) infantum among stocks from immunocompromised, immunocompetent patients and dogs in Spain.

Leishmania (Leishmania) infantum is the causative agent of both the cutaneous and visceral forms of leishmaniasis in southwest Europe; the dog is the main reservoir. In order to identify the L. (L.) infantum zymodemes present in Spain, a total number of 85 Leishmania stocks isolated from dogs (31), HIV-positive patients (46) with visceral or cutaneous leishmaniasis, a patient with visceral leishmaniasis complicating renal transplantation (1) and immunocompetent patients (7) with visceral or cutaneous leishmaniasis, have been characterized by isoenzyme typing. All canine stocks were MON-1, which is the most widespread zymodeme in the Mediterranean area. In immunocompetent patients three zymodemes were found: MON-1 (2), MON-24 (2) and MON-34 (3). Nine different zymodemes were obtained in stocks from HIV co-infected patients, indicating a higher variability of L. (L.) infantum amongst them: MON-1 (in 21 stocks), MON-24 (7), MON-28 (1), MON-29 (3), MON-33 (7), MON-34 (1) and MON-183 (4). Two new zymodemes, MON-198 (1) and MON-199 (1), were described among HIV patients from Spain. The stock from the renal transplanted patient was MON-1. The exclusive presence of certain zymodemes in immunocompromised patients and their absence in typical cases of cutaneous and visceral leishmaniasis and in infected dogs suggests two possibilities: (i) an anthroponotic pattern of leishmaniasis where intravenous drug user-infected patients act as potential reservoir for these new zymodemes. In the latter, syringes could act as the vehicles for infected monocytes; (ii) the cellular immune system could select virulent from non-virulent zymodemes in immunocompetent visceral leishmaniasis patients.

Visceral leishmaniasis in Angola due to Leishmania (Leishmania) infantum.

A 26-year-old man from Angola with no history of travel outside the country presented with typical symptoms of visceral leishmaniasis. The parasite was isolated and biochemically characterized using both kinetoplast DNA and nuclear DNA probes and showed a strong homology with Leishmania (Leishmania) donovani sensu lato (s.l.). When the nuclear DNA of the isolate was hybridized with a specific Leishmania (L.) infantum probe, the pattern obtained showed a clear signal with this species. To establish its identity more specifically, this isolate was typed using a 15-system isoenzyme panel and thick-starch gel electrophoresis, and was identified as L. (L.) infantum zymodeme 1 (MAD-1), the most widespread zymodeme in Mediterranean countries. One case of visceral leishmaniasis has been reported in Angola, but this case is the first report of L. (L.) infantum in Africa south of the equator.

Lavado peritoneal diagnóstico / Diagnostic peritoneal lavage

Estudio prospectivo realizando LPD en pacientes con duda diagnóstica de lesión intraabdomina, se incluyen 30 pacientes con edad promedio de 33,1 años, 16 lavados fueron positivos todos los cuales fueron intervenidos, encontrándose lesiones intraabdominales de importancia en el 93% (un falso positivo). El resto, con LPD negativo, evolucionó sin complicación intraabdominal

Rehabilitación del niño con disrrafia espinal / Rehabilitation of the child with spinal dysraphia

De acuerdo a experiencias obtenidas en relación a afecciones de orígen genético y malformaciones congénitas diagnosticadas en los Institutos de Rehabilitación Infantil, podemos aseverar que estas patologías han ido en aumento, siendo una de las más relevantes la disrrafia espinal. Queremos destacar lo fundamental que es, en el proceso de rehabilitación de estos menores descapacitados, el trabajo conjunto de un equipo multidisciplinario, paralelo a la participación constante de los padres, todo lo cual apunta al logro de una integración del niño a la vida activa, en las mejores condiciones posibles

¿Es necesario dejar drenaje después de colecistectomía electiva? / Is it necessary to drain after the elective cholecistectomy?

Se analiza en forma prospectiva y randomizada, la necesidad de drenar o no el espacio subhepático después de colecistectomía electiva, en un grupo de 124 pacientes operados en forma consecutiva en Hospital Regional de Copiapó. Los pacientes drenados presentaron una mayor incidencia de vómitos en el postoperatorio que los sin drenar. Un 4,8% de los pacientes drenados presentó infección de herida operatoria, mientras que el 1,6% de los no drenados, presentó infección (p:n.s.). Complicaciones pulmonares o de otro tipo menores se presentaron con igual frecuencia en ambos grupos. La estadía postoperatoria, así como la analgesia empleada, fue similar en ambos grupos. No hubo mortalidad en esta serie

Otras alternativas técnicas en el transplante hepático heterotópico experimental / Other technical alternatives in the experimental heterotopic hepatic transplantation

Presentamos nuestra técnica en el transplante hepático heterotópico en perros. Antes de anastomosar las cavas a nivel infrahepático, colocamos un by-pass endocavo multifenestado, para evitar problemas de drenaje venoso del hígado. Este catéter intracavo permite maniobrar dirigidas a obviar los riesgos de sangramiento y alteraciones electrolíticas y cardiovasculares

Profilaxis antibiótica en la colecistectomía por colecistitis aguda / Antibiotic prophylaxis in cholecistectomy for acute cholecistitis

Con el fin de evaluar la utilidad de la profilaxis antibiótica en colesistectomía por colecistitis aguda efectuamos un trabajo prospectivo randomizado en 81 pacientes, 39 pacientes recibieron el esquema antibiótico de ampicilina 1 gr. EV y gentamicina 1,5 mg. x Kg. de peso IM, una hora antes de la operación. No se observó infección de nigún tipo en niguno de los 2 grupos; y sólo hubo un caso de fiebre postoperatoria en cada grupo, que fueron tratados satisfactoriamente con antibióticos. De acuerdo a estos resultados, no recomendamos el uso de antibióticos profilácticos en la colecistectomía por colecistitis aguda, en pacientes en las que se espera tabla de complicaciones sépticas inferior al 5%

Modificaciones al modelo experimental de trasplante hepático ortotópico / Modifications to the experimental model of orthotopic liver transplantation

Se presenta nueva técnica en trasplantes hepáticos experimentales en perros. Utilizando, como variantes del modelo clásico de Starzl, dos by-pass, uno portoyugular y otro endocavo, logramos reducir el tiempo total de clampeo y de las cavas, con las consiguientes menores alteraciones cardiovasculares, electrolíticas y riesgo de sangramiento