scholarly journals Concentric needle single fiber electromyography: normative jitter values on voluntary activated Extensor Digitorum Communis

2007 ◽  
Vol 65 (2b) ◽  
pp. 446-449 ◽  
Author(s):  
João Aris Kouyoumdjian ◽  
Erik V. Stålberg
Keyword(s):  
Action Potentials ◽  
Normal Values ◽  
Normal Subjects ◽  
Extensor Digitorum ◽  
Single Fiber ◽  
Extensor Digitorum Communis ◽  
Mean Values ◽  
Upper Limit ◽  
Neurophysiological Test ◽  
The Mean

Single fiber electromyography (SFEMG) is the most sensitive clinical neurophysiological test for neuromuscular junction disorders, particularly myasthenia gravis. Normal values for jitter obtained with SFEMG electrode have been published, but there are few publications for concentric needle electrode (CNE). The aim of this study was to discuss the possibilities to analyse the jitter in CNE recordings and to get normal values of jitter for voluntary activated Extensor Digitorum Communis using disposable CNE. Fifty normal subjects were studied, 16 male and 34 female with a mean age of 37.1±10.3 years (19-55). The jitter values of action potentials pairs of isolated muscular fibers were expressed as the mean consecutive difference (MCD) after 20 analysed potential pairs. The mean MCD (n=50) obtained was 24.2±2.8 µs (range of mean values in each subject was 18-31). Upper 95% confidence limit is 29.8 µs. The mean jitter of all potential pairs (n=1000) obtained was 24.07±7.30 µs (range 9-57). A practical upper limit for individual data is set to 46 µs. The mean interpotential interval (MIPI) was 779±177 µs (range of individual mean values was 530-1412); there were no potentials with impulse blocking. The present study confirms that CNE is suitable for jitter analysis although certain precautions must be mentioned. Our findings of jitter values with CNE were similar to some other few reports in literature.

A New Method for Determining Impulsive Time Constants and Their Application to Clinical Data

1978 ◽  
Vol 86 (1) ◽  
pp. ORL-81-ORL-89 ◽  
Author(s):  
Andrew W. Sills ◽  
Vicente Honrubia
Keyword(s):  
Clinical Data ◽  
Convenient Method ◽  
Normal Values ◽  
Normal Subjects ◽  
New Method ◽  
Time Constants ◽  
Mean Values ◽  
Significant Difference ◽  
The Mean ◽  
Standard Deviations

We have developed an accurate, convenient method for determining unique values of vestibular time constants from impulsive tests. The method was used to determine the mean values and standard deviations of 36 normal subjects. A comparison between these normal values and data from patients with cerebellopontine (CP) angle tumors or unilateral peripheral vestibular lesions showed no significant difference in the values of the time constants. We conclude that shape-descriptive parameters such as time constants cannot differentiate between subjects and patients.

A COMPARISON OF TWO METHODS FOR MEASUREMENT OF ALDOSTERONE SECRETION RATE IN MAN

1966 ◽  
Vol 53 (2) ◽  
pp. 177-188 ◽  
Author(s):  
P. Lund-Johansen ◽  
T. Thorsen ◽  
K. F. Støa
Keyword(s):  
Urinary Excretion ◽  
Normal Subjects ◽  
Secretion Rate ◽  
Aldosterone Secretion ◽  
Simple Method ◽  
Mean Values ◽  
Pathological Conditions ◽  
Significant Difference ◽  
Derivative Method ◽  
The Mean

ABSTRACT A comparison has been made between (A), a relatively simple method for the measurement of aldosterone secretion rate, based on paper chromatography and direct densitometry of the aldosterone spot and (B) a more elaborate isotope derivative method. The mean secretion rate in 9 normal subjects was 112 ± 26 μg per 24 hours (method A) and 135 ± 35 μg per 24 hours (method B). The »secretion rate« in one adrenalectomized subject after the intravenous injection of 250 μg of aldosterone was 230 μg per 24 hours (method A) and 294 μg per 24 hours (method B). There was no significant difference in the mean values, and correlation between the two methods was good (r = 0.80). It is concluded that the densitometric method is suitable for clinical purposes as well as research, being more rapid and less expensive than the isotope derivative method. Method A also measures the urinary excretion of the aldosterone 3-oxo-conjugate, which is of interest in many pathological conditions. The densitometric method is obviously the less sensitive and a prerequisite for its use is an aldosterone secretion of 20—30 μg per 24 hours. Lower values are, however, rare in adults.

Power spectral analysis of the diaphragm electromyogram

1983 ◽  
Vol 54 (6) ◽  
pp. 1579-1584 ◽  
Author(s):  
T. K. Aldrich ◽  
J. M. Adams ◽  
N. S. Arora ◽  
D. F. Rochester
Keyword(s):  
Power Spectrum ◽  
Signal To Noise Ratio ◽  
Normal Subjects ◽  
Chronic Obstructive ◽  
Signal To Noise ◽  
Low Frequencies ◽  
Mean Values ◽  
The Mean ◽  
Noise Ratio ◽  
Diaphragm Fatigue

We studied the power spectrum of the diaphragm electromyogram (EMG) at frequencies between 31 and 246 Hz in four young normal subjects and five patients with chronic obstructive lung disease (COPD). Diaphragm EMGs were analyzed during spontaneous breathing and maximum inspiratory efforts to determine the effect of signal-to-noise ratio on the power spectrum and if treadmill exercise to dyspnea was associated with diaphragm fatigue. We found that the centroid frequencies of the power spectra (fc) were strongly correlated (r = 0.93) with ratios of power at high frequencies to power at low frequencies (H/L) for all subjects. Of the two indices, H/L had the largest standard deviation expressed as a percentage of the mean. The mean values of both of these decreased significantly after exercise, fc from 100.2 to 97.3 and H/L from 1.07 to 0.97. Signal-to-noise ratios were higher in maximal inspiratory efforts and after exercise in normal subjects and higher in COPD patients. The signal-to-noise ratio was correlated negatively with fc and H/L, indicating that these indices of the shape of the power spectrum are influenced by signal strength and noise levels as well as muscle function. We conclude that the fc and H/L index similar qualities of the power spectrum, that they are partially determined by the signal-to-noise ratio, and that, in some cases, exercise to dyspnea is associated with apparently mild diaphragm fatigue.

Urinary excretion of glycated protein determined with a specific radioimmunoassay

1991 ◽  
Vol 37 (4) ◽  
pp. 504-507 ◽  
Author(s):  
Chizuko Ukita ◽  
Mitsushige Nishikawa ◽  
Akira Shouzu ◽  
Mitsuo Inada
Keyword(s):  
Urinary Excretion ◽  
Normal Subjects ◽  
Mean Values ◽  
Specific Radioimmunoassay ◽  
Glycated Protein ◽  
Highly Sensitive ◽  
Significant Difference ◽  
Group A ◽  
The Mean ◽  
Group B

Abstract We developed a simple and highly sensitive RIA for glycated protein (GP), and used it to measure GP in serum and urine from 15 normal controls and 30 diabetics (14 with urinary excretion rate of albumin, Ualb less than 15 micrograms/min, group A; nine with 15 less than or equal to Ualb less than or equal to 150 micrograms/min, group B; and seven with Ualb greater than 150 micrograms/min, group C). The mean serum concentration of GP was above normal in all groups of diabetics, and the mean glycation ratios of serum protein (SGP) were higher in groups B and C than in normal subjects. Urinary concentrations of GP also were increased in groups B and C, although the glycation ratio of urinary protein (UGP) was decreased in group C. Consequently, the selectivity of urinary excretion of GP (UGP/SGP) was significantly decreased in group C. Moreover, there was a significant difference in the mean values of selectivity between groups of patients with various degrees of retinopathy. We suggest that measurements of serum and urinary GP are useful to evaluate the progression of diabetic complications.

scholarly journals Facial nerve electroneurography: variability in normal subjects

1996 ◽  
Vol 54 (3) ◽  
pp. 393-396 ◽  
Author(s):  
Jovany Luis Alves de Medeiros ◽  
João Antonio Maciel Nobrega ◽  
Luiz Augusto Franco de Andrade ◽  
Yara Juliano
Keyword(s):  
Facial Nerve ◽  
Action Potentials ◽  
Normal Values ◽  
Normal Subjects ◽  
Nasolabial Fold ◽  
Confidence Limits ◽  
Muscle Action ◽  
Surface Electrodes ◽  
Normal Individuals ◽  
Compound Muscle Action Potentials

Twenty normal individuals were submitted to facial nerve electroneurography using different techniques in order to determine the most accurate to obtain the latencies and amplitudes of the compound muscle action potentials (CMAP) of the facial muscles. First of all it was determined in which muscle or muscle group highest amplitude CMAP could be recorded with the lowest variability between sides and in test-retest. Different techniques were studied in order to determine which could give the best results. This was shown to be an arrangement of bipolar surface electrodes fixed to a plastic bar. The records with higher amplitude where obtained from the nasolabial fold muscles. Therefore 65 normal volunteers were examined using this technique and recording the potentials obtained over the nasolabial fold muscles. Normal values were determined (latency lower than 4.5 ms and amplitude larger than 2 mV - 95% confidence limits).

Validation of a new algorithm for the short-term variation of the fetal heart rate: an antepartum prospective study

2018 ◽  
Vol 46 (6) ◽  
pp. 599-604 ◽  
Author(s):  
Christina Kouskouti ◽  
Hella Jonas ◽  
Kerstin Regner ◽  
Pia Ruisinger ◽  
Julia Knabl ◽  
...  
Keyword(s):  
Heart Rate ◽  
Reference Values ◽  
Fetal Heart Rate ◽  
Fetal Heart ◽  
Normal Values ◽  
Short Term ◽  
Mean Values ◽  
Relevant Reference ◽  
Term Variation ◽  
The Mean

Abstract Aims: Currently one of the most widespread systems for the computerized analysis of the fetal heart rate (FHR) is the Dawes-Redman system, where the short-term variation (STV) of the FHR is measured by dividing each minute into 16 segments (STV16). Technical progress has allowed for the development of a new algorithm, which measures the STV by dividing each minute into 240 segments (STV240), thus approximating the beat-to-beat variation. The STV240 still lacks reference values. Our aim was to develop clinically relevant reference values for the STV240 and compare them to the ones for the STV16. Methods: In a single centre, observational study, a total of 228 cardiotocograms were registered and subsequently analyzed with both algorithms (STV240 and STV16). Results: The 95% confidence interval (CI) was calculated for both algorithms. The values of the STV240 were significantly lower in comparison to the ones of the STV16. Not only the mean values but also the 95th percentile of the STV240 lay beneath the existent cut-off value for the STV16. Conclusions: Every clinician using the new algorithm must be aware that the normal values for the STV240 lie beneath the, up until now, established cut-off values for the STV16.

Simplified radioimmunoassay of bradykinin in human plasma.

1980 ◽  
Vol 26 (3) ◽  
pp. 429-432
Author(s):  
P S Verma ◽  
P E Lorenz ◽  
G E Sander
Keyword(s):  
Molecular Mass ◽  
Human Plasma ◽  
Normal Values ◽  
Normal Subjects ◽  
Single Step ◽  
Relative Molecular Mass ◽  
Blood Samples ◽  
Analytical Recovery ◽  
Assay Tube ◽  
The Mean

Abstract A greatly simplified radioimmunoassay for bradykinin in human plasma is described. Current techniques require multiple chromatographic steps or extraction procedures with analytical recoveries of bradykinin of often less than 60%. We present a method in which bradykinin is separated from components of higher relative molecular mass (including kininogens) in a single step, by use of a column of Sephadex G-25 medium (PD-10). The mean analytical recovery of tritiated bradykinin added to plasma is 85.5% (SD, 3.5%). The sensitivity of this radioimmunoassay is 25 pg per assay tube, equivalent to 125 ng per liter of plasma. Twenty to 30 blood samples may be completely processed and assayed within 6 h. As determined with this technique, concentrations of bradykinin in plasma from apparently normal subjects ranged from 2.5 to 5.2 microgram/L (mean 4.2, SD 1.1 microgram/L); these values are consistent with previously reported normal values.

Concentrations of total and free dehydroepiandrosterone in plasma and dehydroepiandrosterone in saliva of normal and hirsute women under basal conditions and during administration of dexamethasone/synthetic corticotropin

1990 ◽  
Vol 36 (12) ◽  
pp. 2042-2046 ◽  
Author(s):  
L M Swinkels ◽  
H A Ross ◽  
A G Smals ◽  
T J Benraad
Keyword(s):  
Chromatographic Separation ◽  
Luteal Phase ◽  
Normal Values ◽  
Normal Subjects ◽  
Follicular Phase ◽  
Strongly Correlated ◽  
Dynamic Tests ◽  
Combined Administration ◽  
Before And After ◽  
The Mean

Abstract Using a specific and sensitive radioimmunoassay involving extraction with diethyl ether and chromatographic separation of steroids, we measured concentrations of salivary and plasma dehydroepiandrosterone (DHEA) in 22 women with normal ovulatory cycles (ages 18-45 years). Salivary DHEA values closely correlated with total and free DHEA in plasma. In the follicular phase the mean concentrations of salivary and plasma free DHEA were virtually equal [mean (SD): 0.61 (0.32) and 0.56 (0.34) nmol/L, respectively]. In the luteal phase, salivary DHEA slightly exceeded the plasma free DHEA [0.68 (0.40) vs 0.56 (0.38) nmol/L, P less than 0.01]. Also, during combined dexamethasone/synthetic corticotropin administration in 25 patients with androgenizing disorders and in 10 normal subjects (each in the follicular and luteal phases), the concentration of DHEA in saliva strongly correlated with total and free DHEA in plasma. During these dynamic tests, the mean concentrations of free DHEA in plasma and salivary DHEA in the hirsute women were significantly higher than the mean concentrations in the control women at all times before and after corticotropin infusion (P less than 0.05- less than 0.0001). In contrast, plasma total DHEA in patients exceeded nonhirsute values only at 15 min after corticotropin administration. In six of 25 patients total DHEA during combined administration of dexamethasone/synthetic corticotropin exceeded normal values by at least 2 SD. The response of salivary and free DHEA to synthetic corticotropin in this subgroup was also excessive.

CD59 Deficient Granulocytes in High Risk Groups of Myelodysplastic Syndromes (MDS).

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4717-4717
Author(s):  
Georgia Kaiafa ◽  
Vasiliki Tsavdaridou ◽  
Athanasios Papadopoulos ◽  
Christos Savopoulos ◽  
Apostolos Hatzitolios ◽  
...  
Keyword(s):  
Normal Subjects ◽  
Risk Groups ◽  
Mean Value ◽  
Control Group ◽  
Refractory Anaemia ◽  
Mean Values ◽  
Significant Difference ◽  
The Mean ◽  
Group B ◽  
Pnh Clone

Abstract Background: Blood cells are deficient in membrane-bound glycosyl-phosphatidylinositol (GPI)-anchored proteins in paroxysmal nocturnal hemoglobinuria (PNH) because of an acquired disorder of the pluripotent stem cell. CD55 and CD59 antigens are the most common GPI-anchored proteins that are used for the diagnosis of the presence of PNH clone. The association of MDS with PNH is rather controversial. There are few published individual cases of PNH arrived from a previous MDS or MDS following PNH. Aim: Recent studies have demonstrated the existence of PNH clone in some MDS patients. These studies were performed mostly on erythrocytes and to the best of our knowledge they are only 4. Granulocytes appear to be more sensitive markers of PNH clone existence than erythrocytes and therefore we investigate the expression of PNH clone on granulocytes of patients with MDS. Material-Methods: A total number of 95 patients 25–80 yrs old with MDS {A:19 with refractory anaemia (RA), B:9 with refractory anaemia with ring sideroblasts (RARS), C:17 with refractory anaemia with excess blasts (RAEB), D: 12 with refractory anaemia with excess blasts in transformation (RAEB-t) and E: 19 with chronic myelomonocytic leukemia (CMLL)} and 19 healthy donors were included in our study. The presence of GPI-anchored proteins (CD55, CD59)-deficient granulocytes was examined by flow cytometry. For the detection of the PNH clone the commercial kit by Beckman Coulter (cellquant CD55/CD59) was used. Statistical analysis was made by ANOVA, while Robust test was performed because there was no homogeneity of variances by ANOVA. Results: Table 1 shows the percentages of CD55 and CD59 deficient granulocytes in the 5 groups of pts with MDS comparing with the control group. a) Although the mean values of CD55 deficient granulocytes in the groups RAEB, RAEB-t and CMLL were higher enough than those of the normal subjects, there were no statistically significant differences (p>0.10) in the comparison of the mean values of CD55 deficient granulocytes between each group of patients with the control group. b) On the contrary there was a very statistically significant difference in the comparison of the mean value of CD59 deficient granulocytes between the three last groups (C, D and E) of pts with the control group (p< 0.086, p< 0.001 and p<0.001 respectively). The percentages of CD55 and CD59 deficient granulocytes in the 5 groups of patients with MDS and in the control group CD55 CD55 CD59 CD59 Groups N Mean Value Std deviation Mean Value Std deviation A (RA) 19 2.89 2.79 2.91 2.85 B (RARS) 9 1.05 1.14 3.89 3.63 C (RAEB) 17 4.78 4.76 11.75 6.06 D (RAEB-t) 12 4.23 2.85 23.76 8.53 E (CMLL) 19 6.01 4.97 38.26 16.18 Control 19 3.67 2.89 3.67 2.89 Total 95 4.00 3.87 14.44 16.39 Conclusions: There are relatively large CD59 negative subpopulations (mean values 11.75–38.26%) of granulocytes in the last three groups (RAEB, RAEB-t, CMLL) of MDS patients. On the contrary the two low risk forms (RA, RARS) revealed no such populations. Non-expression of CD59 antigen on granulocytes is a more sensitive marker than that of CD55 antigen for the presence of a possible PNH clone in MDS patients.

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