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Biomedical subjects

S Prună

Publications and source records attributed to S Prună.

8 recordsLinked to original sources
PubMed1990

Improved technique for testing autonomic dysfunction: evaluation of transient behaviour of the autonomic response.

The transient behaviour of the autonomic response has been studied by means of a reactometer incorporating self-balancing of the electrodermal impedance. This instrument has been used for the indirect measurement of certain parameters associated with the autonomic response detected as skin electrical resistance relative variation (SERV) and capacitance (SECV). Transient signals of the electrodermal impedance response were obtained online by differentiating the analogue output of the impedance reactometer: d(SERV)/dt and d(SECV)/dt. We describe here how the use of the transient signals of the electrodermal impedance response can improve the accuracy and reduce variability and dispersion of the results and how autonomic conduction velocities (ACV) can be indirectly measured.

Autonomic Nervous System↗
PubMed1989

Measurement of perception threshold to an electric stimulus using a phase-sensitive technique in normal and diabetic subjects.

To evaluate the functional state of peripheral sensitivity we measured the perception threshold to an electrical stimulus applied deeply at the level of the lower limbs in both diabetic and nondiabetic patients. The data were obtained using a phase-sensitive technique with a sinusoidal applied voltage at 1592 Hz. The test signal applied through needle electrodes was monitored using a current-to-voltage convertor, the current being considered to have two components, one resistive (IR) in phase with the voltage V across the electrodes, and the other capacitive (IC) 90 degrees out of phase. A significantly (p less than 0.001) higher perception threshold was found in diabetic patients than in nondiabetic subjects with all three electrical variables measured: IR, IC and V.

Adolescent↗
PubMedDate not supplied

The perception threshold to an electric stimulus deeply applied in the lower limbs in normal and diabetic subjects.

The loss of sensitivity to nociceptive stimuli is one of the main factors involved in the pathogeny of diabetic gangrene. The aim of this study was to develop a simple and practical method for selecting the cases prone to such a complication. The perception threshold (either voltage, mV or current, microA) was determined in 137 randomly selected diabetic patients and 38 non-diabetic controls, by an original electronic device using sinusoidal waves, delivered through two electrode needles introduced at a depth of 0.5 cm at two points located on the anterior aspect of the shank about 12 cm apart. At each of the eight frequencies studied (10, 20, 50, 100, 200, 500, 1000 and 2000 Hz) three electrical parameters (voltage across the needle electrodes, the resistive and the capacitive current component) were recorded when the subject first perceived the stimulus. A significantly higher perception threshold was found in diabetic patients vs. non-diabetic subjects, at all frequencies studied and with all three electrical parameters recorded. A greater difference in the perception threshold between diabetic and non-diabetic subjects (a ratio higher than 3) was, however, found using the resistive component of the current and at frequencies higher than 200 Hz.

Adolescent↗
PubMedDate not supplied

Electroacupunctogram: a new recording technique of the acupoint potentials.

The monitoring of the bioelectric activity of acupoints by means of electroacupunctogram (EAG) represents a direct and precise recording technique of the acupoints functional state. The EAG recording is done by introduction in the acupoint at corresponding depth of a standard silvered-steel electrode-needle and the measurements are made bipolar, i.e., versus a reference electrode. Useful information can be obtained by studying the difference in the electroacupoint potential in the following conditions: during introduction of the electrode-needle into the acupoint; after mechanical stimulation (by rotation) of the electrode-needle; after indirect heating of the acupoint; after deep breathing of the subject; by shunting the point investigated with a homonymous acupoint. The paper is based on the analysis of the EAG traces recorded in 112 apparently healthy subjects and in 230 patients affected by different diseases.

Action Potentials↗
PubMedDate not supplied

Evaluation in autonomic diabetic neuropathy using a dual-channel self-balancing impedance reactometer. Preliminary study.

The electrodermal reflex to an external acoustic stimulus was determined by means of an original device "'The Neurovegetative Reactometer", as variation of the skin electric resistance delta R/R (recorded on millimetric paper) and latency in the appearance of the response (seconds), in 39 diabetic patients (20 males, 19 females, aged 55 +/- 10 years, and the duration of diabetes of 6 +/- 4 years) with or without clinical neuropathy and, comparatively, in 24 apparently healthy controls. The results showed a statistically significant difference both between the amplitude of the skin electric resistance variation evaluated on millimetric paper (6.77 +/- 4.06 mm versus 22.79 +/- 5.39 mm in the controls, p less than 0.001) and latency (4.29 +/- 1.55 versus 2.49 +/- 0.57 seconds, p less than 0.001). These two parameters reflect quantitatively the skin sympathetic activity in lower limbs. The results obtained recommend neurovegetative reactometry as a practical, non-invasive, rapid and readily applicable method, which is highly technical and sensitive for evaluating autonomic dysfunction in diabetic neuropathy.

Autonomic Nervous System Diseases↗
PubMedDate not supplied

Diabetic gangrene: medical and surgical causes and consequences.

Diabetic gangrene is the chronic complication which involves many medical, economic and social problems. In this study we have analyzed the medical and surgical causes and consequences of diabetic gangrene on three groups of patients: 120 patients (96 males and 24 females; aged (X +/- SD) 57 +/- 14 years hospitalised in the Clinic of Diabetes, Nutrition and Metabolic Diseases of the "N. Paulescu" Institute, 72 patients (59 males and 13 females; mean age 60 +/- 10 years) hospitalised in the Surgical Clinic of Cantacuzino Hospital; 29 patients (23 males and 6 females; mean age 58 +/- 11 years) hospitalised in the Cardiovascular Department of Fundeni Hospital. The analyses of data obtained showed: in 77% of cases the initial lesions might have been avoided by an appropriate education programme of the patients; in 66% of cases the progression of lesion from medical to surgical stage was caused by tardily coming of patient to physician; average duration of hospitalization was 27 days in the Clinic of Diabetes, Nutrition and Metabolic Diseases, 33 days in the Clinic of Surgery of "Cantacuzino" Hospital and 25 days in Cardiovascular Department of Fundeni Hospital; the surgical mortality was 8%; 47% operated patients were cured and 53% were incompletely cured and required more out patient care; 35% were thigh amputations, that shows the high invalidity potential of diabetic gangrene; the cost of medical and/or surgical care of diabetic gangrene is higher than the cost of hospitalisation for other patients; the diabetic gangrene predominantly neuropathic was better cured and the arteriopathic component breaks the medical curing and impose high amputations; diabetic gangrene is more frequent with older people, but with young people it is a cause of early retiring and psycho-social concern.

Aged↗