Dynamic and spatial features of the inhibitory pallidal GABAergic synapses.

The globus pallidus, one of the basal ganglia nuclei, plays a major role in both basal ganglia physiology and pathophysiology. The globus pallidus is innervated mainly by striatal spiny neurons and globus pallidus collaterals. These GABAergic synapses constitute 90% of the input to globus pallidus cells. Despite the dominance of this inhibitory GABAergic input, globus pallidus cells are spontaneously active and most of them increase their firing rate in a task related manner. To explain this apparent inconsistency, we studied the dynamic and spatial effects of GABAergic inputs to globus pallidus neurons. To this end, we used intra-cellular recording from globus pallidus neurons in rat brain slices, investigating the effect of bath and local GABA application, as well as the responses to electrical stimulation of the striatum. We showed that the properties of the responses to either local or global GABA applications are similar to the responses of globus pallidus cells to GABA release from nerve terminals. Since the stimulus-evoked responses have been shown to be inhibitory in nature, we concluded that GABAergic inputs to globus pallidus both at soma and dendrite level are inhibitory. Furthermore, we showed that GABA can promote globus pallidus synchronization by affecting the timing of globus pallidus spiking, and that the globus pallidus GABAergic synapse undergoes rapid frequency-dependent depression. This prominent synaptic depression can account for the ability of globus pallidus neurons to fire in the presence of a majority of inhibitory inputs and might indicate that globus pallidus neurons are tuned to detect frequency changes. Furthermore, globus pallidus synaptic depression rules out the possibility of activation of GABAeregic afferents as the main mechanisms of high-frequency deep brain stimulation, used for treatment of severe parkinsonian patients.

[Budd-Chiari syndrome: updated treatment modalities].

Budd-Chiari Syndrome (BCS) refers to hepatic venous outflow obstruction, resulting in simultaneous occurrence of hepatic congestion and portal hypertension, leading to a typical clinical triad consisting of right upper quadrant pain, hepatomegaly and ascites. Contrary to Asia and Africa, where BCS is caused primarily by an obstructing membranous web, BCS in the western world is considered a thrombotic complication of an underlying hypercoagulable state. Recognition of the contribution of hypercoagulability as a causative factor in BCS, has led to acknowledgement of the importance of anti-coagulant therapy in BCS. Indeed, a conservative approach consisting of diuretics and anti-coagulant therapy is considered an appropriate treatment strategy for the BCS patient, in the absence of significant hepatic insult. However, once disease progression is noted, based on clinical symptoms, hepatic laboratory disturbance or histological evidence of irreversible hepatic damage, a definite invasive treatment should be applied. The specific procedure to be used is dependent upon the extent of hepatic insult and the anatomical characteristics of the venous obstruction in any individual patient. In the absence of significant hepatic damage, one may employ surgical shunting or invasive roentgenic measures, such as TransJugular Intrahepatic Porto-Systemic Shunt procedure, for the decompression of the portal system. Alternatively, in cases of a single localized obstruction, one may use balloon angioplasty with stent insertion. In contrast, upon evidence of significant hepatic damage, liver transplantation becomes necessary. To date, numerous studies report excellent results regarding the success of liver transplantation for patients with advanced BCS disease accompanied by significant hepatic damage.

[Core body temperature monitoring using the telemetric pill].

Exposure to extreme weather or physical work conditions can lead to dangerous core temperature changes, and to the clinical syndromes accompanying them. Core temperature measurement is the main tool for diagnosing these syndromes. Recent technological advances particularly NASA's telemetry and miniaturizing technologies, have led to the development of a CorTemp Ingestible Temperature Sensor, or "pill". The pill is a small electronic device, which senses the body's temperature and transmits it through a radio wave signal to an external receiver. The advantage of the pill over other temperature measurement devices is that it is a simple device that enables core temperature measurement for many hours without the need of any wire connections or other cumbersome instruments. For this reason, the pill is an ideal tool for core temperature measurements in field locales or for continuous long duration temperature monitoring of ambulatory patients. The following study reviews available literature concerning the use of the pill and the validity of its measurements. A high correlation has been revealed between pill temperature measurements and rectal or esophageal measurements. Pill temperature values usually fall between the high rectal and the low esophageal measurements, considered the gold standard for core temperature measurement. A number of studies emphasizing the advantage of the pill are presented in this review.