Methods of ultrasonic angiography and spectrum analysis of the Doppler signal in the diagnosis of the degree of occlusive lesions of the brachiocephalic arteries

Results of an examination of 39 patients are described and critically assessed. An analysis of the resolving power of the method of ultrasonic angiography in pathological formations of major vessels of the neck is given.     

Clinical Evaluation of Automatic Tachycardia Diagnosis by an Implanted Device

Reliable discrimination between sinus tachycardia (ST) and pathologic tachycardia has been a major problem for automatic implantable antitachycardia devices. In patients whose sinus response to activity is as rapid or faster than their pathologic tachycardia (rate crossover), these unsophisticated devices deliver the programmed tachycardia response to either the pathologic or sinus tachycardia. Over a one-year period, 50 Intermedics Intertach Model 262–12 antitachycardia pulse generators were implanted to evaluate the specificity of a new group of tachycardia recognition algorithms. Patients were subjected to exercise testing and noninvasive programmed stimulation to demonstrate the efficacy of this new approach. The five recognition algorithms tested were various combinations of the following criteria: high rate HR), sudden onset (SO), rate stability (RS), and sustained high rate (SHR). False positive rates (tachycardia response inappropriately triggered by ST) were as follows: HR (93%); HR + SO (3%); HR + RS (63%); HR + (RS or SHR) (87%); HR + HS + SO (8%). Pair-wise significance testing between HR only and HR + SO (p < 0.001), HR + RS (p = 0.01) and HR + SO + RS (p < 0.001), demonstrated a significant reduction in the rate of false positives through the use of the sudden onset and rate stability criteria in concert with the standard high rate criterion.     

Neurofilament M and calbindin D28k are present in mutually exclusive subpopulations of enteric neurons in the rat submucous plexus

Immunocytochemical methods have been used to examine the localisation of 3 neurofilament proteins and the calcium binding protein, calbindin D_28k, in whole mount preparations of the submucous plexus in the Wistar rat. Neurofilament-M (160 kDA protein) was present in 40% of the submucosal neurons, staining fine filaments in the soma and the axonal processes. Calbindin D_28k was present in 40% of the submucosal neurons staining both the soma and nerves within the plexus. The neurofilament proteins and calbindin D_28k were never observed within the same neurons. Neurofilament-M was co-localised with substance P and calcitonin gene-related peptide but not somatostatin or the other neuropeptides investigated. Calbindib D_28k was co-localised with vasoactive intestinal polypeptide and neuropeptide Y. Galanin- and somatostatin-immunoreactive neurons did not contain either the neurofilament proteins or calbindin D_28k. The results demonstrate the presence of subsets of submucosal neurons that can be distinguished by the presence of neurofilament-M or calbinsin D_28k.     

Behavioral state-specific changes in human hippocampal theta activity

Although there has been extensive examination of the behavioral and physiologic correlates of hippocampal theta activity in animals, the human literature consists of a single case study. We investigated the differential effects of four behavioral states on human hippocampal theta activity in 16 epilepsy surgery patients. Behavioral conditions included resting eyes closed (RC), resting eyes open (RO), eyes open with auditory word activation (AW), and eyes open with visuospatial activation (VS). Hippocampal theta activity decreased during both RO and VS compared to both RC and AW. There were reciprocal changes in delta activity. Comparisons of RO to VS and of RC to AW were nonsignificant. The results demonstrate state-specific changes in human hippocampal theta and are consistent with the animal literature that relates hippocampal theta to sensorimotor integration and forebrain volitional mechanisms.     

Short and middle latency vestibular evoked responses to acceleration in man.

We have succeeded in recording short and middle latency vestibular evoked responses in human subjects. The head was held rigidly in a special, patented head holder, constructed individually for each subject, which gripped the teeth of the upper jaw. The stimulus consisted of 2/sec steps of angular acceleration impulses produced by a special motor with intensities of about 10,000 degrees/sec 2 and with a rise time of 1-2 msec. The electrical activity was recorded as the potential difference between special forehead and mastoid electrodes having a large, secure contact area with the skin. The activity was digitally filtered and averaged in 2 separate channels by means of a Microshev 2000 evoked response system. The short latency responses, with peaks at about 3.5 msec (forehead positive), 6.0 msec (forehead negative) and 8.4 msec (forehead positive; bandpass: 200-2000 Hz; average of 1024 trials), had amplitudes of about 0.5 microV. The middle latency responses had peaks at about 8.8 msec (forehead positive), 18.8 msec (forehead negative) and 26.8 msec (forehead positive; 30-300 Hz; N = 128 trials), with larger amplitudes (about 15 microV). These responses were consistently recorded in the same subject at different times and were similar in different normal subjects. Strenuous control experiments were conducted in order to ensure that these responses are not artefacts due to the movement of conducting media (head, electrodes and leads) in the electromagnetic field of the motor and are elicited by activation of normal labyrinths.(ABSTRACT TRUNCATED AT 250 WORDS)     

A problem-solving approach to group psychotherapy in the inpatient milieu

Because of the trend toward a marked decrease in length of psychiatric hospitalization, clinicians need to improve the organization of the therapeutic milieu so that behavioral changes can be effected more rapidly. A university general psychiatric unit has adapted a problem-solving model that integrates groups and activities so that each one focuses on complementary behavioral objectives for each patient with the aim of effecting more rapid behavior change. The stages of the model are incorporated in a weekly sequence that begins with a goal-setting group. In a series of subsequent groups, each patient tries to develop and implement a solution to the problem identified that week. At the end of each week, patients participate in a goal review group, with feedback from staff and peers and self-reinforcement. The model can be used with a diverse patient population without interfering with each patient's individual psychotherapy or pharmacotherapy.