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PubMed2002

[Relation between anthropometric indicators and electrocardiogram variability].

AIM: To investigate which combination of anthropometrical parameters influence significantly the variability of the magnitude spatial vectors of atrial (sPmax), activation and ventricular (sQRSmax) activation and ventricular depolarization (sTmax). Quantification of these relationships can improve the reliability of criteria for normal values of ECG and VCG characteristics. SUBJECTS AND METHODS: The study group consisted of 195 healthy boys and men without signs of cardiac disease, with normal ECG and VCG, aged from 7 to 70 years, (median = 19 years). Electrocardiologic variables were obtained by Frank lead system in seated persons from a single heartbeat by the computer system Cardiac 128--PC (METE, Prague) in mid respiration. 30 anthropometrical measurements were taken including biceps, triceps, subscapulare and suprailiacare skinfold thicknesses. Proportionality of body and thoracic shape was evaluated according indexes computed from body height, weight (Body mass index, Rohrer and Ponderal index), circumferences (Relative abdominal circumference, Pignet index), anteroposterior and transversal dimensions (Thoracic index, relative sagittal diameter). Values of the 15th and 85th percentil of relevant indexes were taken as criteria for stratification of the sample into three subgroups demarcating the constitutional types. Differences in maximal spatial vector magnitudes between these subgroups were tested by variance analysis ANOVA. Relationships to anthropometrical and vectorcardiographic parameters were expressed also by regression equations. RESULTS: The average magnitudes of maximal spatial vectors increased during maturation and early adulthood: sPmax, approximately up to 17 years, sQRSmax and sTmax up to 22 years. The magnitude of ventricular vectors decreased after this period. With increasing endomorphy, which is indicated by values of Rohrer index, relative abdominal circumference and fat percentage, magnitudes of sPmax, s QRSmax and sTmax decreased (p < 0.001) on the other hand they increased with higher linearity (Ponderal index) and index of fitness (Pignet index). The greatest differences (by 50%) were found in values of sPmax, whereas distributions of ventricular vectors sQRSmax differed by 20-30%. CONCLUSIONS: The variability of magnitudes of maximal spatial vectors was significantly influenced by the proportionality of body constitution independently of age. The tightest relationship of sTmax was found with fat percentage. Influence of anthropometrical parameters was most pronounced in younger adulthood and should be taken into account when evaluating of electrocardiograms and vectorcardiograms.

Adolescent↗
PubMedDate not supplied

[Occupational risks in the maintenance of pot-lining and anode firing furnaces].

A group of 66 pot-lining and anode furnace maintenance workers was examined, including 44 workers who had been exposed to these occupational hazards for more than one year. No occupational bronchial diseases were observed. Two cases of 1/0 grade silicosis and two cases of initial palmar aponeurosis retraction were reported. Seventeen cases (38.6%) of occupational hearing loss had been compensated or reported. Hearing loss exceeding the 2nd degree of the Merluzzi scale was observed in 11 workers. There were 13 cases of hearing loss (29.5%) according to ISO criteria, due to exposure levels calculated at 95/100 dB-A eq. Spirometry revealed only one worker with marked reduction in vital capacity. Urinary fluoride concentrations (1.37, S.D. = 0.63 pre-shift and 2.32, S.D. = 1.15 post shift) did not indicate any particular level of hazard. ECGs showed no significant alterations. Variance analysis and multiple regression techniques were used to study the relationship between respiratory volume, hearing capacity, age, duration of exposure and length of past exposure in the construction industry. A marked association was observed between age and hearing loss and a weaker association between duration of exposure and hearing loss.

Adult↗
PubMed1992

[Colored matrices test (special scale): how to evaluate and interpret it in our milieu].

Raven's "Colored Matrixes" (Special scale) were specially adapted for 5- to 11-years-old children by their author. The present paper analyzes: 1) The importance of taking into account wrong responses to the matrixes since they are likely to occur at a higher (5/6) probability level than correct responses (Burnbaum, 1968; Bock, 1972); 2) The proposal of considering the Colored Matrixes as a test with cultural reduced influences. The findings of a research carried out with 790 preschool- and schoolchildren (ranging 4- to 11.5-years-old) in Argentina are presented: Total scoring, and series scoring are shown. By means of a multiple variance analysis it has been found out that both age and series, as well as the interaction between both have a statistically significant influences on score variations. Besides, new evaluation guidelines are presented.

Analysis of Variance↗
PubMed1992

[A simultaneous study of intestinal permeability and the test of H2 in the expired breath of celiac children].

Permeability test with sugars (PTS) as a non-invasive diagnostic tool is of special interest in pediatric patients. This study evaluated the relationship between PTS and antigliadin antibodies (AA) with the intestinal biopsy and studied whether an altered expired hydrogen test (EHT) could interfere in this relation in celiac patients. Thirty children (13 girls, 17 boys) with diagnosis of celiac disease (ESPGAN criteria) were divided into three groups according to this histopathology: Group A (n = 23) normal biopsy; Group B (n = 7) biopsy grade III or IV; Group C (n = 25) controls. The intestinal permeability test showed significative differences (p < 0.01) of Group B (0.159 +/- 0.03) with Group A (0.048 +/- 0.005) and with the control Group C (0.039 +/- 0.002). The cut-off for the Youden maximum index (0.75) was 0.092 and ROC SE 0.87 +/- 0.7. The results of the AA were related to those of the PTS. The variance analysis showed that the results of the expired hydrogen test do not interfere statistically on the good correlation of PTS with the histology. The PTS is a good indicator of the status of intestinal mucosa. There is a good correlation between PTS and AA in celiac children. A pathological expired hydrogen test seems not to interfere with the correlation found between PTS and histological damage in our series.

Adolescent↗
PubMed2004

[Discussion of a biometrical model for the evaluation of feeding, age, and animal effects on transport properties of small intestinal mucosa].

This paper is concerned with the question in which ways study results can depend on the choice of the statistical model and factors included in this model. This is shown using example data of a study dealing with the effects of an Enterococcus faecium as probiotic in the diet of pigs. We focused on the effects on transport properties of pig jejunum. The experimental design was the following: the sows and piglets were randomly assigned to two different feeding groups. The control group was fed a conventional diet and the experimental group was additionally supplemented with a probiotic preparation of Enterococcus faecium NCIMB 10415. The animals were divided into four age groups. Two samples of five animals of each feeding and age group were taken and mounted into conventional Ussing chambers. Glucose transport rates were measured by changes in short-circuit current (Isc) of the pig jejunum epithelium. The appropriate reference base for evaluation of effects of feeding or age on Isc is the variation between animals which are submitted to identical conditions relating to these factors. To refer explicitly to this variation a random animal effect has to be included in the statistical model of variance analysis. Otherwise the variation between animals could be underestimated. With the example data set conclusions for the factor "feeding" would be different depending on whether a random animal effect is included in the model or not.

Age Factors↗
PubMed2004

The fractal dynamics of self-esteem and physical self.

The aim of this paper was to determine whether fractal processes underlie the dynamics of self-esteem and physical self. Twice a day for 512 consecutive days, four adults completed a brief inventory measuring six subjective dimensions: global self-esteem, physical self-worth, physical condition, sport competence, attractive body, and physical strength. The obtained series were submitted to spectral analysis, which allowed their classification as fractional Brownian motions. Three fractal analysis methods (Rescaled Range analysis, Dispersional analysis, and Scaled Windowed Variance analysis) were then applied on the series. These analyses yielded convergent results and evidenced long-range correlation in the series. The self-esteem and physical self series appeared as anti-persistent fractional Brownian motions, with a mean Hurst exponent of 0.21. These results reinforce the conception of self-perception as the emergent product of a dynamical system composed of multiple interacting elements.

Adult↗
PubMed2004

Streamwater chemistry and flow dynamics along vegetation-soil gradient in a subalpine Abies fabri forest watershed, China.

Streamwater chemistry and spatial flow dynamics from a subalpine Abies fabri forest in an experimental watershed located in the east slope of Gongga Mountain were analyzed to gain insights into the gradient effect of primary community succession on the stream biogeochemical process. Results showed that high sand content (exceeding 80%) and porosity in the soil(exceeding 20% in A horizon and 35% in B horizon), as well as a thick humus layer on the soil surface, made the water exchange quickly in the Huangbengliu (HBL) watershed. Consequently, no surface runoff was observed, and the stream discharge changed rapidly with the daily precipitation. The flow trends of base ions in the stream water were influenced by the Abies fabri succession gradient. Ca2+ , HCO- and SO4(2-) were the dominant anions in the streamwater in this region. A significant difference of Ca2+, HCO3(-) and SO4(2-) concentration exported between the succession stages in the watershed can be found. But they had the similar temporal change in the stream flow. Ca2+, HCO3(-) and SO4(2-) showed significantly negative correlations with the daily precipitation and the stream discharge. Concentrations of Cl-, Na+, K+, and Mg2+ were low in all streamwaters monitored and we observed no differences along the Abies fabri succession gradient. Low ratios of Na: (Na + Ca) (range from 0.1 to 0.2) implied cations were from bedrock weathering (internal source process in the soil system) in this region. But, a variance analysis showed there were almost no differences between rainwater and streamwaters for Mg2+ , Na+, K+, and Cl- concentrations. This indicated that they might be come from rainfall inputs(external source). The highly mobile capacity, rapid water exchange between precipitation and discharge, and long-term export lead to this observed pattern were suggested.

Abies↗
PubMed2004

A model in environmental training--The University / Elementary School / Municipality Cooperation.

This study targets development of an effective training scheme model that can be implemented at elementary school level with focus on recovery and recycling of wasted papers in Turkey. For this purpose, three schools were chosen from a district within Istanbul. They were separated from one another as full intervention (FI), semi-intervention (SI) and control (C) schools. Different levels of educational activities carried out in the schools, mostly in the FI school, were directed toward being informative as regards recycling and the development of a positive attitude. Afterwards, in order to evaluate the effects of the training, paper wastes were collected in recycle bins placed at appropriate points in schools and weighed on a weekly basis. Quite a significant result was found (p = 0.0001), when the difference was calculated through the Kruskal Wallis Variance Analysis method, regarding the weekly average amount of paper in each of the three schools against per person. Furthermore, when the results were evaluated and compared as to the ones before the 2.5 months summer vacation and the ones after it, the seven measurements taken before (p = 0.001) and the eight taken afterwards (p = 0.0001), were found to have valid differences, once again, as against schools. The results show that the approach we provided to education is an effective method not only for the collection of paper wastes but also for applications in various areas of health education.

Analysis of Variance↗
PubMed2005

Growth responses of Picea mongolica seedlings to defoliation rate.

Picea mongolica W. D. Xu. is an endemic species in China. The spruce forest is only found in semi-arid habitat in Inner Mongolia Autonomous Region of China. Based on the simulative defoliation experiment, it was proved that Picea mongolica seedlings had the compensatory and overcompensatory effects under the certain defoliation rate. The results of variance analysis on growth indexes showed that in PM I (natural regeneration seedlings under Picea mongolica forest), the differences of H1 (height in June 23) and H2 (height in September 3) were extremely significant, and the difference of D(diameter at the breast height) were not significant. In PM II (artificial regeneration seedlings under Betula platyphylla Suk. forest), the difference of H1 was significant, the difference of H2 was not significant, and the difference of D was extremely significant. The regression equations were established and the compensatory and overcompensatory points were obtained. In PM I, the compensatory points of H1, H2, and D were 0.7628, 0.7436, 0.5725, and the overcompensatory points were 0.6056, 0.5802 and 0.2909 respectively. In PM II, the compensatory points of H,, H2, and D are 0.5012, 0.3421, 0.2488, and the overcompensatory points are 0.4137, 0.2633 and 0.0747 respectively. These results suggested that the induction of compensatory growth mechanisms in spruce seedlings required a threshold level of defoliation, and the insects in Picea mongolica forest could be controlled in a certain degree.

Analysis of Variance↗
PubMed2005

[Early, noninvasive diagnostic of osteoporosis in men].

Osteoporosis is the most frequent metabolic bone disease. Until recently it was believed to mainly affect women in menopause. A review of the literature indicates that a lot of the research to date on women. The patogenesis of bone loss in men has not been explained yet. It has not been determined what is the contribution of androgens as opposed to environmental factors and stimulants. The behaviour of bone turnover markers during ageing and their role in diagnosing the risk of osteoporosis development and fractures in men are not clear. The objective of the paper was to evaluate bone metabolism markers and to determine their relevance in early diagnosis of osteoporosis in men, and to determine any possible impact of testosterone concentration on bone mass. The study covered 100 volunteers-males, aged 40-85. All were subjected to a densitometric examination, using theDEXA method, of three regions of the osseous system: lumbar spine in anterior-posterior height, proximal femur, distal radius. Based on these results, subjects were divided into three groups: without osteoporosis, with osteopenia and with osteoporosis. In all men the serum level of the following was marked: 1) 3 markers of bone formation: osteocalcin (BGP), bone alkaline phosphatase (b-ALP) and Procollagen I Aminoterminal propeptide (PINP); 2) 2 markers of bone resorption: Collagen Type I Crosslinked C-telopeptide (Ctx) and Tartarate Resistant Acid Phosphatase (TRAP); 3) testosterone. The results obtained were subjected to thorough statistical analisis. Mean concentrations of bone metabolism, testosterone and calcium consumption in the groups examined were compared by mean of ANOVA variance analysis and the smallest significant difference test. Relationship between markers of bone resorption and formation, testosterone level and bone mineral density (BMD) were shown by means of Pearson linear correlation. The relevance of markers in the diagnosing of osteoporosis in men was evaluated by means of the ROC curves. The results obtained lead to the following conclusions: Among the markers of bone turnover analysed, Collagen Typ I Crosslinked C-telopeptide (Ctx-serum) is the most useful marker in the diagnosis of osteoporosis in men, followed by Tartarate Resistant Acid Phosphatase (TRAP) and osteocalcin (BGP). There is no relationship between bone mineral density and serum testosterone level.

Absorptiometry, Photon↗
PubMedDate not supplied

Electromyographic analysis of the masseter and temporal muscles in oralized deaf individuals.

Deaf individuals show a number of difficulties related to the functionality of the stomatognathic system, mainly by reason of the little or no use of facial musculature during speech either due to the use of sign language or to the difficulty that these individuals have in articulating words. The stomatognathic system muscles play important roles in functions such as mastication, deglutition, and phonation. This study aimed to assess, by means of computerized bilateral electromyography (EMG), masseter and temporal muscles of 12 oralized deaf individuals in clinical activities that involve part of this masticatory musculature and compare this system's functionality with that of 12 normal listening individuals, performing the same activities. An 8-channel K6-I EMG Light Channel Surface Electromyography device was used (Myo-Tronics Co.Seattle, WA, USA), in addition to disposable double electrodes covered with silver chloride (Duotrodes; Myo-tronics Co., Seattle, WA) containing a conductor gel (Myogel- Myo-tronics Co., Seatlle, WA). The averaged rectified EMG values were normalized with reference to the EMG amplitude induced by a maximum bite force. The statistical analysis confirmed that there were any significant differences between the groups, clinical activities, and muscles, and also effects of interaction among them. The analysis made use of Variance Analysis (ANOVA). Significant differences (p < 0.01) for both muscles were found among the clinical conditions, with deaf individuals showing greater electromyographic activity for both muscles for the clinical activity protrusion. Deaf individuals showed a lower muscular activity for clinical activities that demanded a greater masseter and temporal muscular activity such as mastication, mouth opening and closing, and dental compression. Greater electromyographic values were found for both deaf individuals and healthy controls during clinical activities of mastication and dental compression. Based on the obtained data, we concluded that deaf individuals showed a lower activity of the masticatory musculature than healthy individuals; the differences were significant at the level of p < 0.01 between the performed clinical activities; and all deaf individuals and healthy controls showed greater electromyographic values for mastication and dental compression.

Adolescent↗
PubMed1991

Repeatability of dynamic eye pupil response measurement using the Pupilscan instrument.

The repeatability of pupil response measurements made with the Pupilscan instrument has been assessed. Two operators made 32 repeat recordings of the pupil response in each eye of eight normal subjects over four days. A total of 512 recordings were made and the results analysed by variance analysis. Room light levels were carefully controlled. The instrument measured initial pupil diameter, and after a 0.2 s light stimulus measured minimum and final diameters, maximum diameter change, constriction velocity and time to minimum diameter. For all measurements except time to minimum, there were significant differences (P less than 0.001) between the normal subjects. Day-to-day variation was also significant (P less than 0.005), but did not mask the differences between subjects. It is concluded that the average of at least four repeat measurements are made, giving error ranges similar to those observed from day-to-day changes.

Adult↗
PubMed1991

[Seasonal variations of lipids and arterial pressure].

BACKGROUND: The presence of a seasonal variation in serum lipids and blood pressure is often described in the literature. METHODS: With the aim of analyzing this seasonal influence blood pressure and lipid (total cholesterol and cholesterol corresponding to different lipoprotein, triglycerides and AI and B apolipoprotein families) values were studied over 12 months in 36 normotense healthy males (mean age 36 +/- 6 years), a third of whom presented diverse base lipid alterations. A variance analysis of the relative intraindividual values (to study monthly differences) was carried out and a Student's t test was performed for the absolute values and grouped into two periods (summer and winter) and according to two categories (normal and hyperlipemic). RESULTS: No significant modification was observed in any of the parameters studied with the exception of the intrapersonal variation coefficient of the triglycerides which was significantly higher in the hyperlipemic individuals. CONCLUSIONS: In the population studied no seasonal modification was observed in blood pressure or different lipid concentrations analyzed. The slight variation of temperature observed and the elevated sunstroke in Spain in addition to the youth of the population studied may explain the lack of seasonal variation.

Adult↗
PubMed1991

[Atrial natriuretic factor: one of the mechanisms of action of the phlebology bath at Barbotan].

UNLABELLED: The effect of thermal baths on oedema of the lower limbs might be explained by physical mechanisms of hydrostatic pressure resulting from the use of a deep bath and a centripetal underwater jet, by which the veins and lymph ducts are drained every day. The purpose of this experiment is to demonstrate the existence of hormonal mechanisms which would account for the diuretic effect of thermal baths. One of the effects observed with hydrotherapy is the physiological diuresis that follows each bath, this diuresis would appear to depend at least in part on the atrial natriuretic factor (ANF). The criteria by which assessment can be made essentially biological: ANF level and its biological effects on blood and urine; aldosterone level; plasma renin activity (PRA); creatinine clearance; hematocrit; proteinemia; and blood and urine electrolyte balance. The inclusion criteria are: subjects selected at random and willing cooperate. The criteria for exclusion are disease states which modify ANF kinesis: congestive heart failure, cardiac rhythm disorders, decompensated cirrhosis of liver, obesity, treatment antihypertensive drugs. METHODS: Thirty patients were put through the same experimental sequence, as follows: emptying of the bladder and ingestion of 200 cc of water; seated rest fort 30 mn, after which (to): blood sample; urine sample; ingestion of 200 cc of water; deep bath for 20 mn, i.e. the basic hydro treatment in phlebology at Barbotan. The deep bath is specific to Barbotan and the patient is subjected to maximum immersion in water at a mesothermal temperature of 34.5 degrees C, followed by (t1): blood and urine sample; ingestion of 200 cc of water; supine rest for 90 mn, followed by (t2): blood and urine sample. RESULTS: Data from twenty-eight patients were usable. In this protocol, we use variance analysis with repeated measurements and a 95% confidence limit. The mean value of the principal parameters studies are set out in the following table; these value are accompanied by the degree of significance of the modification at (t1) and (t2). Our experimentation with thirty patients showed that the big thermal bath at Barbotan produces a highly significant increase in ANF secretion, resulting in the diuresis observed after the use of the bath. The antagonist effect of AFN on the renin--angiotensin-aldosterone system was corroborated: we found decreased aldosterone, PRA and creatinine clearance, and increased diuresis and natriuresis. The renal and cardiovascular effects observed after extended immersion in the Barbotan bath (increased diuresis, tachycardia and hypotension, transitory venous vasoplegia and ephemeral vasodilatation of the surface capillaries) are the result of increased ANF secretion. [formula: see text] Supine rest immediately after the bath is essential. This sustains the enhanced ANF and thus reinforces its renal effects, while reducing adverse cardiovascular effects such as the orthostatic hypotension and venous vasoplegia that are normally observed after use of the bath. Moreover, by reducing venular and lymphatic pressure, clinostatism facilitate interstitial to intravascular tissue fluid exchanges and thus helps to drain oedema from the legs. It is striking to note that the hydrotherapy prescribed at Barbotan les Thermes has always included the three most potent factors for ANF release: deep immersion in the big bath, immediate supine rest, and walking. Physiological diuresis has thus been induced empirically as an essential part of the treatment of lower limb phlebopathies.

Aldosterone↗
PubMed1990

[Investigation of the castings marginal adaptation using investment expansion methods].

The research in the field of metal casting has recorded a continual progress in dentistry. Particularly, due to the economic problems posed by the use of gold alloys relatively inexpensive metal alloys tend to gain increased popularity. Application of such alloys physically in dentistry and their adaptability to various preparations are being studied. In castings where investment expansion methods are employed, and marginal adaptability of castings are evaluated, the results of variance analysis have indicated little significant difference due to the applied methods. However, the hygroscopic method has proved highly successful in terms of marginal adaptability.

Analysis of Variance↗
PubMed1990

[Study of left ventricular filling by gamma-angiography and echocardiography].

In order to establish which indices of early diastolic function obtained by Doppler echocardiography and the time/activity curve of 99mTc radionuclide angiography are the most useful clinically, the two investigations were performed in 41 subjects aged 52 +/- 15 years. The maximum velocity of LV filling and mitral E wave provided the best correlation (r = 0.48); the Doppler A wave did not correlate with its scintigraphic homologue. The correlations with the morphological data (mass, thickness/radius ratio) were better with radionuclide angiography. Variance analysis of E and maximum velocity of filling showed that gamma angiography was significantly more accurate (FE LVF greater than 10 p = 10 - 4); on the other hand, the A wave best illustrated the transfer of filling to late diastole. In conclusion, left ventricular filling may be assessed clinically by Doppler echocardiography; the greater accuracy of the radionuclide measurements with respect to left ventricular volumes makes this a more appropriate method when quantitative information is required.

Adult↗
PubMed1988

[Comparison of protein concentrations in saliva and serum].

Saliva and serum protein profiles composed of 12 proteins: IgA, IgG, IgM, albumin, transferrin, alpha 1-glycoprotein acid, alpha 2-macroglobulin, alpha 1-proteinase inhibitor, haptoglobine, C3C, C4 and CRP were obtained by laser nephelometry of aliquots of samples of non-stimulated whole saliva and blood taken at the same time. The population of 138 controls of both sexes was divided into 4 age groups: 1 (20 to 29 years), 2 (30 to 39 years), 3 (40 to 49 years), 4 (50 to 60 years). Using the techniques developed for saliva assay, 10 proteins were measurable: IgA, IgG, IgM, albumin, transferrin, alpha 1-glycoprotein acid, alpha 2-macroglobulin, alpha 1-proteinase inhibitor, haptoglobulin and C3C. The C4 fraction and CRP were present at concentrations lower than the detection limit i.e. at 1.8 and 2.05 mg/l. In the serum 11 proteins were analysed, CRP occurring at less than 0.01 g/l. The statistical two-factor variance analysis test (sex and age) demonstrated the statistically significant influence of age in the saliva for alpha 1-PI and alpha 2-M in the serum for Tf, alpha 2-M and alpha 1-PI, and sex in the serum for IgG, IgM, alpha 1-PI, alpha 2-M and also the interaction of both factors in the serum for alpha 2-M.

Adult↗
PubMed1989

[Tracing and measuring errors in the roentgenographic cephalometry].

In the present study, thirty cephalometric films which had been used in three different investigations using almost the same parameters were selected and divided into two groups. Twenty-three parameters in the first group and nine parameters in the second, which were used in two and three investigations respectively, were statistically compared. Paired t test was used in the first group and variance analysis in the second group. In conclusion, a lot of parameters exhibited statistically significant variability, while some of them were not.

Analysis of Variance↗