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D Ruano

Publications and source records attributed to D Ruano.

45 records · Page 3Linked to original sources
PubMed1991

Pharmacologic characterization of GABAA/benzodiazepine receptor in rat hippocampus during aging.

We have characterized the pharmacologic properties of the gamma-aminobutyric acid (GABAA)/benzodiazepine receptor complex in hippocampal membranes from 3-month- and 24-month-old Wistar rats. No major changes were found in [3H]flunitrazepam or [3H]muscimol binding parameters. Neither the dissociation constant(s) nor the Bmax for either ligand seemed to be modified during aging in hippocampus. Furthermore, the allosteric interaction between the barbiturates binding site and the GABA binding site, determined by pentobarbital stimulation of [3H] muscimol binding, remained unaltered. However, there was a significant increase with aging in the efficacy of the GABA-enhancement of [3H]flunitrazepam binding. On the other hand, we have also detected a significant increase in the proportion of type I benzodiazepine receptor in 24-month-old hippocampal membranes. We propose that the age-related increase in the efficacy of GABA-enhancement of [3H]flunitrazepam binding could be correlated with the increase in the proportion of type I benzodiazepine receptor. Based on these results it is tempting to speculate that the age-dependent modifications on the GABAA/benzodiazepine receptor might reflect an age-dependent neuronal degeneration of the hippocampus or the hippocampal formation.

Aging↗
PubMed1983

The infrapiriformis foramen syndrome resulting from intragluteal injection.

The authors describe a syndrome resulting from a lesion at the level of the infrapiriform foramen due to intramuscular injection, with involvement of the sciatic nerve, the inferior gluteal nerve, the posterior femoral cutaneous nerve and the pudendal nerve. This appears to be the first case of a complete syndrome of the infrapiriform foramen to be reported. In a second case the pudendal nerve was not involved and a releasing neurolysis was performed with remarkable postoperative relief. All the reported cases with involvement of the inferior gluteal nerve are associated with a more or less complete injury of the sciatic nerve. Conversely, the cases of injection injury to the superior gluteal nerve are rarely associated with injury of the sciatic nerve. The anatomic reasons that might explain both kinds of lesion are given. Finally some aspects of 131 cases of sciatic paralysis resulting from injection are also examined.

Adult↗
PubMed1978

New approach to the splenic vessels.

The transperitoneal approach is used systematically for an arterial or a venous splenorenal anastomosis. However, this approach is associated with high morbidity and mortality rates. Because of our anatomical and surgical findings we have used the retroperitoneal approach to the splenic hilus by means of the lumbar region. The first splenorenal arterial anastomosis with this approach was done in 1972. The approach has proved to be less aggressive since it avoids the danger of damaging the pancreas, it is a more direct approach to the splenic vessels and it provides better exposure and facilitates the anastomosis. In addition, the loss or infection of ascitic fluid in cirrhotic patients is avoided with this approach, as well as intraoperative hemorrhaging caused by the great surplus circulation. There has been neither mortality nor complications in the 13 cases of arterial and venous splenorenal anastomoses that we have done with this method.

Humans↗
PubMedDate not supplied

Long-term cryopreservation of human donor corneas.

The purpose of the present study was to develop an optimal freezing method for cryopreservation of human donor corneas for transplantation. Three groups of ten human donor corneas each were cryopreserved using cooling rates of 0.5 degree C/ min, 1 degree C/min and 9 degrees C/min. The freezing medium contained 10% fetal calf serum and 7% dimethylsulphoxide. Ten additional human donor corneas were used as controls. Endothelial cell survival after complete thawing was assessed by calculating the mean endothelial cell density and percentage of non-viable endothelial cells from vital staining and scanning electron micrographs. Significant differences in endothelial cell survival between all groups were detected by analysis of variance (p < 0.001), but paired contrast found no real differences between corneas frozen at 0.5 degree C/min or 1 degree C/min. Nevertheless, 60% of the corneas cryopreserved at 1 degree C/min but only 10% of those cryopreserved at 0.5 degree C/min fulfilled both requirements to be considered suitable for transplantation (endothelial cell density > 2000 cells/mm2 and less than 10% dead cells). None of the corneas frozen at 9 degrees C/min fulfilled these requirements. Mean endothelial cell density of corneas frozen at 1 degree C/min was 2084 cells/mm2 (range 2020 to 2630 cells/mm2). Except for isolated corneas frozen at 0.5 degree C/min, only corneas cryopreserved at a cooling rate of 1 degree C/min achieved satisfactory endothelial cell survival for their use in transplantation. However the significant interindividual variability among corneas frozen at 1 degree C/min (ANOVA: p < 0.001) prevents prediction of the condition of the cornea after the complete cryopreservation process. Until this high variability can be drastically reduced, systematic corneal cryopreservation in eye banking remains unattainable.

Adult↗
PubMedDate not supplied

Complicated pulmonary aspergillosis with pneumothorax and pneumopericardium in a child with acute lymphoblastic leukemia.

Invasive aspergillosis is a fungal infection that is being observed increasingly in immunocompromised patients due to the use of more aggressive chemotherapeutic regimens. To our knowledge, no case of pneumothorax and pneumopericardium associated with invasive pulmonary aspergillosis has been reported to date. High-dose amphotericin B (1 to 1.5 mg/kg/day) is the treatment of choice, although severe side effects, especially hypokalemia, are very common. Itraconazole is considered to be a therapeutic alternative for invasive pulmonary aspergillosis in immunocompromised patients. A rare combination of pneumothorax and pneumopericardium associated with systemic aspergillosis in a child with acute lymphoblastic leukemia is described. Treatment with low-dose amphotericin B and itraconazole achieved complete resolution of the foregoing complications.

Amphotericin B↗
PubMedDate not supplied

Alpha-fetoprotein in tumours derived from cystic and simple embryoid bodies.

Cellular aggregates called embryoid bodies (EB) have been obtained from the experimental teratocarcinoma (TC) 0TT6050. Two morphological types of EB can be differentiated, which are injected subcutaneously into isogenic 129/Sv mice. The tumors are collected 20 and 30 days after EB injection and processed histologically, and immunohistochemically with anti-alpha-fetoprotein (alpha-FP) antibodies. Our results indicate that the histological pattern of the tumors is related to the degree of morphological organization of the EB used.

Animals↗
PubMedDate not supplied

[Etiopathogenesis of so-called congenital hydronephrosis].

Taking up again inquiries already known in the past, documents of pathological anatomy of his own person experience, and facts of embryology, the authors explain the etiology of the obstructive malformation of pyelo-ureteral function the etiology brings out two phenomena: --The insufficient hollowing of the cephalic end of the ureteral bud, which is initially grooved, when it detaches itself from the Wolffian canal, can transform itself into a full cellular cord which secondarily forms a groove after 23 mm stage.--The insufficient vascularization of the ureter just below the pelvis because of an abnormal anatomical disposition which causes displacement of the longitudinal uretero-pelvic arteries to a point clearly below the ureteropelvic junction. There an ischemia impedes the muscular development of the ureter just below the pelvic of which the wall becomes more sclerotic and fibrous than muscular. Thus a defect in the grooving of the ureteral bud and an arterial blood deficit results in a congenital ureteral stenosis. Pathological anatomical documents illustrate this theory from which flow two imperative technics; the necessity to eliminate the initial obstructive ureteral segment; care to protect the pelvic vessels which will have to vascularize the ureter which will be anastomosed to the cut edge of the pelvis.

Adult↗