Cushing's Syndrome: A Historic Review of the Treatment Strategies and Corresponding Outcomes in a Single Tertiary Center over the Past Half-Century.

Cushing's syndrome (CS) is associated with serious comorbidities and an increased mortality rate that could be reduced only if strict biochemical control is achieved. The aim of this study was to show the 50-year experience of a single tertiary center in the management of CS patients - the different treatment modalities used over the years and the corresponding outcomes. It was a retrospective study of a large cohort of patients from the Bulgarian CS database: 613 patients (374 with ACTH-dependent and 239 with ACTH-independent CS).

Anticipatory postural adjustments associated with arm movements during balancing on unstable support surface.

This study aims to investigate the pattern of anticipatory postural adjustments associated with arm movements during balancing on unstable support surface as a mechanism of coordination between movement and posture in this specific motor task. The experiments were arranged in two series: (1) the subjects stood on a force platform, and (2) on unstable platform (see-saw). They performed self-paced arm elevations as fast as possible for each support condition.

Modulation of somatosensory evoked potentials during coordination between posture and movement.

Somatosensory evoked potentials (SEPs) elicited during execution of voluntary movements undergo modification in their amplitude ('gating'). We have studies SEP changes during a motor task that includes anticipatory postural adjustment and focal movement. Upright standing subjects were performing fast forward elevation of one arm.

Brain macropotentials associated with distinct phases of voluntary sustained isometric contraction in man.

Brain potentials recorded from the scalp during voluntary sustained isometric contraction have been consistently found to accompany both the beginning and the termination of the contraction. This study attempts to evaluate the dependence of the potentials related to the voluntary termination of a sustained effort on the physical parameters of the motor task and also to further investigate the relationship between potentials related to the initiation and to the termination of action. Brain potentials from healthy male volunteers performing hand-grip squeeze were time-locked to (1) beginning of contraction; (2) execution of an additional effort; and (3) the moment of voluntary relaxation, and then averaged.

Somatosensory evoked potentials modification related to isometric voluntary contraction.

Somatosensory evoked potentials were elicited by applying an electrical stimulus to the median nerve while the subjects performed a handgrip isometric contraction. Somatosensory evoked potentials (SEPs) were recorded from scalp positions C3 + 2 and C3-2. SEPs during the increase phase and decrease phase of force, and during the hold phase (period of maintenance of steady force) of isometric contraction were compared with potentials during rest.

Somatosensory evoked potentials during compound thumb movement.

The aim of the study was to assess the influence of a biphasic flexion-extension movement upon somatosensory evoked potentials (SEPs). Voluntary thumb flexion initiated a sequence of either single or single PLUS sustained electrical stimulation upon the median nerve. In cases of sustained stimulation the subjects had to overcome the induced tetanic thumb flexion.

Modulation of somatosensory evoked potentials during isometric contraction in relation to hand use.

The aim of the study was to assess the effect of the hand used on the modulation of somatosensory evoked potentials (SEPs) during isometric contraction. SEPs to median nerve stimulation were assessed during dynamic (increase and decrease of force) and hold phases of isometric contractions. The experiments were carried out with the right or left hand.

Stance does interfere with movement related brain potentials.

Movements of the upper limb are well known to be preceded by electromyographic activity in leg and trunk muscles known as postural preadjustment. Brain potentials preceding the actual commencement of voluntary displacement were also described. The relationship between the occurrence of these two electrophysiological phenomena was investigated by performing two types of movement in three different body positions.

Movement related brain potentials accompanying a non-productive voluntary action in humans.

This study assessed the effects of training and ability to execute a voluntary movement upon movement-related brain potentials (MRBPs). A self-paced thumb flexion initiated a sequence of autotriggered electrical stimuli over the median nerve that caused a twitch opposing the intended thumb extension. The MRBPs had earlier onsets during the first runs of skill acquisition than during later training sessions; they occurred earlier when they preceded a stimulus train than when they preceded a single stimulus; the onset was earlier over the vertex than over the premotor area.

Somatosensory evoked potentials during standing posture on different support surface.

Somatosensory evoked potentials in response to stimulation of the posterior tibial nerve at the ankle were recorded during standing on stable ground or on unstable support surface (seesaw) or on support surface short in relation to foot length. During standing on the seesaw and on the short support surface a decrease in the amplitude of the early component (N32-P39) was observed. The amplitude of N49-P58 decreased during standing on the short support surface.

Spatio-temporal characteristics of SEP to tibial nerve stimulation.

Source derivation techniques have recently been applied to analyse the spatial distribution of brain potentials. Somatosensory evoked potentials (SEPs) to tibial nerve stimulation recorded at 8 sites were analysed by using 2 source derivation techniques: Laplacian and criterion, presented by Kossev et al. (1988).

Postural adjustments upon arm movement during sinusoidal induced body oscillations.

Postural adjustments due to the fast forward right arm elevation, performed during sinusoidal induced body oscillations in the phase of platform-induced dorsal, as well as plantar flexion of the foot were studied. Start times of the changes in the cyclic way of the center-of-gravity position (SG) and right ankle goniogram (GG) as well as the EMG onsets of the right soleus (S), anterior tibial (AT) and femoral biceps (FB) muscles relative to the ipsilateral anterior deltoid muscle (AD) EMG onset were measured. The EMG onset of FB muscle was found to occur significantly before the EMG onset of the AD muscle during plantar flexion series, wherever during dorsal flexion series the EMG onset of the AT muscle was significantly before the AD muscle EMG onset.

Effect of body and foot positions on the somatosensory evoked potentials.

Somatosensory evoked potentials in response to stimulation of the posterior tibial nerve at the ankle were recorded during sitting and standing with variable foot positions. During standing a decrease in the amplitude of the early positive component was observed. The deviation of the foot from a horizontal position was associated with an increase in the amplitude of the early negative component.

Postural adjustments associated with a fast voluntary arm movement at various foot positions.

The aim of the study was to further investigate postural adjustments associated with a fast voluntary arm elevation at various foot positions. The subjects stood upright on a force platform and participated in 3 sessions according to foot position: horizontal position, dorsal and plantar flexion of 6 degrees. EMG activity of anterior deltoid muscle (DA) and of ipsilateral and contralateral soleus (SD, SS), biceps femoris (BFd, BFs) and ipsilateral anterior tibial (TAd) muscles, initial acceleration (Acc) and stabilogram change (Sg) were recorded.

Chemo- and immunotherapy of an adenovirus-induced transplantable sarcoma in hamsters.

The subcutaneous transplantable adenovirus sarcoma (TAVS) in hamsters was created in 1972 at the Oncological Research Institute and maintained by serial subcutaneous transplantation. It showed the highest sensitivity against some alkylating drugs and antimetabolites--cyclophosphamide, sarcolysine, methotrexate and 6-mercaptopurine. In some degree, TAVS is able to differentiate antitumor drugs of one group by the intensity of their antitumor activity.

Somatosensory evoked potentials upon electrical stimulation triggered by voluntary movement.

The autotriggered signal was presented with a varying delay. SEP obtained without movement of the thumb (control series), SEP of autotriggered stimuli and movement-related brain potentials (MRBP) without stimuli were registered. The EEG was recorded from C3 + 2 and C3 = 2.

Motor unit activity during different functional states of the neuromuscular system.

The study showed that the mean interspike interval (ISI) and the variability of ISIs increased with fatigue for both low and high threshold motor units (MUs). The recruitment threshold tension decreased for both the low and high threshold MUs while the recruitment threshold in % of maximal voluntary contraction changed selectively because of decrease of muscle force. During ischaemia after an initial decrease of mean ISI and ISIs' variability there was an essential increase of variability of ISIs at almost the same mean ISI followed by a considerable final increase of both parameters.

Muscular synergies during different conditions of postural activity.

With the view to studying the muscular synergies in maintaining of upright posture EMG activity of soleus (SOL), tibialis anterior (TA), peroneus longus (PL), biceps femoris (BF), vastus lateralis (VL) and gluteus medius (GM) muscles during easy standing, voluntary leaning and induced body oscillations in frontal and sagital plane were recorded. The data showed that during easy standing and during small external disturbances the vertical posture was maintained mainly by the activity of SOL (triceps surae muscle) which was modulated by the modification of the external force field. TA remained silent.

Changes in the Bereitschaftspotential due to subsequent voluntary autotriggered stimulus.

The Bereitschaftspotential (BP) has been studied in two different tasks: simple voluntary isometric flexion/opposition of the thumb and same movement, followed by a mild electrical shock over the median nerve, autotriggered by the movement itself. When the two tasks were organized in separate series, the subject being told about the outcome of the movement beforehand, it was found that: The BP started later; Its amplitude was smaller; The maximum negatively (N2) was smaller, when expecting electrical shock compared to simple voluntary contraction. The decrease was more pronounced over the postcentral areas.

Synchronization of movement-related cerebral potentials for averaging.

A software-oriented technique is proposed for synchronization of the individual movement-related cerebral potentials on the basis of the first derivative of the mechanogram. All procedures are computer performed using neither trigger device nor time-reverse averaging later on. The main advantages of the technique over the trigger approach are demonstrated when determining onset of both commencement and termination of the sustained contraction.