Cardiovascular effects produced by microinjection of angiotensins and angiotensin antagonists into the ventrolateral medulla of freely moving rats

In this study we determined the cardiovascular effects produced by microinjection of angiotensin peptides [Angiotensin-(1–7) and Angiotensin II] and angiotensin antagonists (losartan, L-158,809, CGP 42112A, Sar¹-Thr⁸-Ang II, A-779) into the rostral ventrolateral medulla of freely moving rats. Microinjection of angiotensins (12.5–50 pmol) produced pressor responses associated to variable changes in heart rate, usually tachycardia. Unexpectedly, microinjection of both AT₁ and AT₂ ligands produced pressor effects at doses that did not change blood pressure in anesthetized rats. Conversely, microinjection of Sar¹-Thr⁸-Ang II and the selective Ang-(1–7) antagonist, A-779, produced a small but significant decrease in MAP an HR. These findings suggest that angiotensins can influence the tonic activity of vasomotor neurons at the RVLM. As previously observed in anesthetized rats, our results further suggest a role for endogenous Ang-(1–7) at the RVLM. The pressor activity of the ligands for AT₁ and AT₂ angiotensin receptor subtypes at the RVLM, remains to be clarified.     

Radio-ulnar dissociation. A review of twenty cases.

The results of treatment were reviewed for twenty patients who had sustained concomitant injuries of the lateral compartment of the radiohumeral joint and the ipsilateral distal radio-ulnar joint. The ages of the patients ranged from eight to seventy-four years (average, thirty-five years) and the duration of follow-up ranged from four months to twenty-seven years (average, 113 months). In fifteen patients, the injury of the wrist was diagnosed after a mean delay of seven years and eleven months (range, one month to twenty-six years). In all fifteen, the radial head injury was treated by excision, either initially or after some delay. After excision of the radial head, all fifteen patients complained of severe pain at the distal radio-ulnar joint. The results, on the basis of elbow and wrist scores of fair or better without complications, were satisfactory in only three patients. In the remaining five patients, in whom the injuries of both the elbow and the wrist had been identified at the initial evaluation, the radial head was either preserved or replaced. The results, on the basis of elbow and wrist scores of fair or better, were graded as satisfactory in four of these patients. Our data show that any injury to the lateral side of the elbow should prompt a careful evaluation of the ipsilateral distal radio-ulnar joint for associated instability.     

Synaptic P2X7 and oxygen/glucose deprivation in organotypic hippocampal cultures.

The P2X7 receptor for extracellular ATP is the main candidate, among P2 receptors, inducing cell death in the immune system. Here, we demonstrate the direct participation of this receptor to cell damage induced by oxygen/glucose deprivation, in the ex vivo model of organotypic hippocampal cultures. By pharmacological and immunological approaches, we show that P2X7 is rapidly and transiently up regulated in hippocampal areas eliciting metabolism impairment. Moreover, the P2 antagonists 2',3',-dialdehyde ATP and reactive blue 2 prevent both up regulation of this receptor and hypoxic/hypoglycemic damage. By confocal laser microscopy, we show that P2X7 is present at the synaptic level of fibers extending from the CA1-2 pyramidal cell layer throughout the strata oriens and radiatum, but absent on oligodendrocytes, astrocytes or neuronal cell bodies. Colocalization of P2X7 is obtained with neurofilament-L protein and with synaptophysin, not with myelin basic protein, glial fibrillary acidic protein or a marker for neuronal nuclei. P2X7 up regulation and diffuse cellular damage are also induced by 3'-O-(4-benzoyl) benzoyl-ATP, an agonist selective but not exclusive for P2X7. In summary, our study demonstrates that P2X7 not only directly participates to the hypoxic/hypoglycemic process, but also owns specific phenotypic localization. We do not exclude that it might serve as a sensor of dysregulated neuronal activity and ATP release, both occurring during oxygen/glucose deprivation.     

Malignant teratoma of the thyroid: case report.

Teratomas in the neck are rare neoplasms. Most of them occur in infants less than 1 year and are benign. In contrast, thyroid teratomas in adults are malignant and have fatal outcomes because of spread of tumor refractory to treatment. We report a case of a primary thyroid malignant teratoma in a 37-year-old woman. She was treated successfully with a combination of surgery, postoperative cis-platinum-based chemotherapy, and radiation therapy to the neck. Although the time of follow-up is short (24 months), we attribute her successful outcome to the use of this intensive therapeutic approach.     

Beyond the desktop: emerging technologies for supporting 3D collaborative teams

The emergence of several trends, including the increased availability of wireless networks, miniaturization of electronics and sensing technologies, and novel input and output devices, is creating a demand for integrated, fulltime displays for use across a wide range of applications, including collaborative environments. In this paper, we present and discuss emerging visualization methods we are developing particularly as they relate to deployable displays and displays worn on the body to support mobile users.     

Aortic-left ventricular tunnel. A case report

It is described a clinical case of aorto left ventricular tunnel, initially diagnosed as aneurysm of the right Sinus of Valsalva with aortic incompetence in a 18 years old patient. The rarity of this congenital abnormality, together with a successful surgical correction, stimulated us to publish this case. The patient improved from Class IV to Class I NYHA. The surgery of theses cases doesn't mean necessarily complete cure, because the intracardiac repair can cause aortic valve incompetence, eventually worse than before, and for this reason some surgeons prefer use a patch to close it. However in our adult patient, direct suture was enough to get a good result. In what concerns the Wooler's annuloplasty to correct the mitral incompetence, it was not so well succeeded and we think that we should implant a prosthetic ring instead.     

Emerging targets for the pharmacology of learning and memory.

Learning and memory are dynamic processes associated with modifications in morphology, biochemistry and physiology of the nervous system, that can be analysed at different levels of biological organization. Within this context, changes correlated with cognitive processes are identifiable at distinct cellular and molecular loci of the nervous system. Synaptic plasticity represents an experience-dependent alteration of neuronal properties that subserve learning and memory, and for which a neuronal network can be considered as a candidate for being part of an engram. Multiple molecular systems at various levels of the signal transduction cascade, such as those involving receptors, second messengers and gene expression, may be linked to synaptic remodelling during cognitive processes. After a brief overview of the various facets of memory and the higher levels of cerebral organization (with special attention to the hippocampus), this review is devoted to the presentation of some novel potential therapeutic targets within the signal transduction cascade that might be considered for rational pharmacological intervention to improve learning and memory in both diseased and healthy individuals.