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Biomedical subjects

C Sforza

Publications and source records attributed to C Sforza.

At least 109 records · Page 6Linked to original sources
PubMed1992

Harmonic analysis and clustering of facial profiles.

The profiles of 83 healthy young adults were traced from right-side photographs, and then digitized with an image analyzer; each profile thus consisted of a series of coordinates. A dedicated computer program using Fourier analysis resulted in an equation of a curve that interpolated all profile points. By means of cluster analysis, profile equations were divided; two clusters each were found for male and female subjects. A mean profile was calculated for each of the clusters, so that four mean profiles were obtained. These profiles were compared with esthetic parameters found in literature; the results showed that the conventional parameters could sometimes give misleading information for orthodontic and craniofacial orthopedic treatment plans.

Adult↗
PubMed1991

Morphometric study of the human neonatal ovary.

A morphometric analysis, based on mathematical evaluations and stereological methods, has been used to study five left neonatal ovaries, removed from full-term neonates with a 46,XX karyotype free from malformations of the genital apparatus. Each ovary was completely cut obtaining serial sections and one 1-micron-thick section every 1,000 microns was examined. Ovarian length ranged from 9 to 17 mm (mean 13 mm), width from 3.5 to 7 mm (mean 5.7 mm), thickness from 2.5 to 5 mm (mean 4 mm), and volume from 82.23 to 198.3 mm3 (mean 125.88 mm3). In the ovarian cortex, primitive cortical tissue accounted for 10-20% of the total volume, follicles for 10-25% and interstitium for 35-45%; 10-30% of the organ consisted of inner medulla. The total follicle number ranged from 130,000 to 385,000 per ovary, with an average of 266,000 with 95% being represented by primordial follicles. In all ovaries examined follicular growth was still in process, with follicles at different stages of development.

Female↗
PubMed1991

Reproducibility of electromyographic measures: a statistical analysis.

The masseter, temporalis anterior and digastric anterior muscles of five volunteers have been investigated by means of surface electromyography. Each muscle was tested by three operators at different times and under three distinct conditions of intermaxillary relationship: resting, with no occlusal contact (physiological rest position); occlusion in centric occlusion (C.O.) without clenching force; and maximum voluntary clench. In all the trials the BIO-PAK system (Bio-Research Associates Inc., Milwaukee, WI, USA) was used. Measurements were made in two consecutive experimental trials separated by an interval of about 15 days. In the first trial the operators had minimal instrumental experience, while in the second trial the same operators had minimal instrumental experience, while in the second trial the same operators had performed at least 30 measurements each. The data have been analysed by a factorial variance analysis, particularly with a view to comparing the variability between operators for each volunteer subject. The analysis revealed statistically significant differences only in the first experimental trial, due to the operators' lack of experience. The study demonstrates that the electromyographic system and protocol used allow good reproducibility of measurements. Furthermore, they have potential applications in both clinics and research.

Action Potentials↗
PubMed1991

Cephalometrics and facial shape: new thresholds by an overall approach to classic standards.

Pretreatment lateral skull radiographs were studied to analyze the characteristics of facial morphology. Standard cephalometric measurements were compared with those provided by a Fourier description of the overall morphology. Skull patterns were divided into hyperdivergent, neutral, and hypodivergent groups (1) according to the standard thresholds of facial height ratio and (2) according to the mathematical distance between their Fourier coefficients and the Fourier coefficients of three reference plots. Linear regression analysis showed that all the Fourier variables were significantly correlated. The standard thresholds of normality used to classify patients as normal, hyperdivergent, or hypodivergent did not correlate with each other. Fourier analysis resulted in new thresholds of normality that are more accurate than previous norms developed by standard cephalometric measurements. These new thresholds take into account the overall morphologic characteristics of the patient and each separate measurement is strictly correlated with the others.

Adolescent↗
PubMed1990

Calcification of the stylohyoid ligament: incidence and morphoquantitative evaluations.

To study the incidence of calcification of the stylohyoid ligament, 286 orthopantomographs were analyzed. All patients had no symptoms. The total incidence of calcification was noted to be high, at 84.4%. The number and the length of calcifications increased with age, and there was no relationship to sex or mandibular size. The phenomenon is often evident bilaterally. The variety of results reported in the references depends on different criteria in radiographic evaluation and in patient selection.

Adolescent↗
PubMed1990

Circadian rhythmicity in the rat exocrine pancreas: chronomorphological patterns.

Circadian rhythmicity of the structural morphometric model of rat endocrine pancreas has been studied in 24 Wistar female rats, four months old, kept in LD 12:12. The following parameters were evaluated: the volume fractions of nucleus and cytoplasm of exocrine cells, the size distribution and number in unit tissue volume of acinar cell nuclei, the mean nuclear diameter, the shape coefficient of glandular acini (that is the ratio acinar area/perimeter2 which indicates the shifting of structures from circularity). A statistically significant circadian rhythm was demonstrated for the shape coefficient of glandular acini. Results obtained in the present experiment are compared with data recorded in a previous study.

Animals↗
PubMed1990

Analysis of chewing movement using elliptic Fourier descriptors.

Mandibular kinesiography measures and records the plot of jaw movements in the three spatial planes; this technique not only offers to investigators information about the dynamics of chewing, but also opens important prospects of quantifying dysfunction. At present, chewing patterns are compared on a qualitative basis only, and their morphologic analysis is not accurate. It is therefore necessary to use suitable mathematical algorithms that can manage the data supplied by modern image analyzers without losing the large amount of information they contain. A mathematical model that, by using a Fourier description of the plots of jaw movements, analyzes and characterizes different chewing classes has been developed. As an example of the possible applications, the variability of the exclusively morphologic aspect of the frontal plane plots of the chewing cycle of some subjects under standard conditions was studied and quantified. A morphologic distance between the Fourier coefficients that characterize each plot and the coefficients of a reference plot was also calculated. On these bases it will be possible to define and measure a "normal" chewing cycle under standard conditions and to make an eventual diagnosis of dysfunctional chewing based on a true morphoquantitative evaluation. Moreover, by deepening the analysis of the more occlusal part of the cycle, the model could aid in the identification of unapparent malocclusions.

Fourier Analysis↗
PubMed1987

Circadian rhythms of acid secretion and electric parameters in rat gastric mucosa in vitro.

In male Wistar rats standardized from birth in LD 12:12 conditions (with light from 0700 to 1900 hr), samples of mucosa from the body of the stomach were isolated in vitro and mounted in a Ussing-type chamber. Spontaneous secretion of the hydrogen ion (H+)during 45 min of incubation was measured. Some electric parameters [transmucosal potential difference (PD) and electrical resistance (R)] were detected in the gastric mucosa both during H+ secretion and during inhibition of acid secretion by cimetidine. The variables studied were analyzed with the single cosinor method, and all revealed a circadian rhythm with acrophases during the dark span. The higher values of PD and R found during the dark hours are unrelated to acid secretion and may indicate a greater efficiency of ionic pumps and a limited passive permeability.

Animals↗
PubMedDate not supplied

Coordinated electromyographic activity of the human masseter and temporalis anterior muscles during mastication.

The present report aimed at evaluating the within- and between-subject electromyographic coordination between the masseter (M) and temporalis anterior (T) muscles during the performance of a standardized chewing task. Electromyographic activity of M and T muscles was recorded in 60 young healthy adults (30 men, 30 women) during two 15-s unilateral mastications of gum. Left-right differential potentials (delta M = MR-ML, delta T = TR-TL) were computed and the square root of (delta M2 + delta T2) moduli were calculated. The maximum modulus relative to each masticatory cycle was located, and each modulus and differential potential were expressed as a % of the maximum modulus for each subject and chewing trial. For each subject and chewing side, the masticatory frequency was computed, and statistics of the moduli as %s of the maximum were determined by means of bivariate analysis. Within-subject repeatability of the unilateral chewing patterns was good. Mean population values for the modulus position (bivariate analysis), chewing frequency, and maximum modulus of the differential potentials (univariate statistics) were computed. A significant gender difference was found for the masticatory frequency, with larger values in men than in women. Conversely, no gender or side differences were found for the mean values of the maximum modulus or for the mean position of the percentage moduli. The chewing test applied allowed the evaluation of the neuromuscular coordination during the performance of a standardized physiologic activity. In particular, it quantified the within-subject and chewing side repeatability of the muscular pattern.

Adult↗
PubMedDate not supplied

Morphometry of the normal human ear: a cross-sectional study from adolescence to mid-adulthood.

The objective of this study was to supply information about: (1) normal gender-based dimensions of ears (linear distances and ratios, area); (2) left right symmetry; and (3) growth changes between adolescence and mid-adulthood. The three-dimensional co-ordinates of several soft-tissue landmarks on the ears and face were obtained by an electromagnetic digitizer in 40 male and 33 female adolescents aged 12-15 years. 73 young female and 89 young male adults aged 19-30 years, and 41 male and 38 female adults aged 31-56 years. From the landmarks, paired car width and length were calculated and averaged for age and gender, as well as the relevant ratios, ear areas and angles relative to the facial midline, and indices of left right symmetry. Comparisons were performed by factorial analysis of variance. All ear dimensions were significantly larger in men than in women (P < 0.005). A significant effect of age was found (P < 0.005), with larger values in older individuals. On average, the three-dimensional position of ears was symmetric, with symmetry coefficients ranging between 94 and 96%. Data collected in the present investigation could serve as a database for the quantitative description of human ear morphology during normal adolescent and adult growth.

Adolescent↗
PubMedDate not supplied

Statistical evaluation of some mandibular reference positions in normal young people.

Mandibular rest position, swallowing occlusal position, and maximum opening were evaluated in a sample of healthy young adults (52 male, 27 female) using a mandibular kinesiograph. It was found that males have a significantly greater vertical dimension of rest than do females, while there were no gender differences in the maximum opening. Most of the subjects had a swallowing occlusal position that coincided with or was very near to the position of maximum intercuspation. Reported data allow the definition of a three-dimensional normal range of variability of maxillomandibular positions during the functional tests most frequently used.

Adolescent↗
PubMedDate not supplied

Heart rate and extrasystolic arrhythmias in active subjects aged over 90. A chronobiological study.

We analyzed the circadian rhythm of heart rate (HR), of simple atrial premature beats (APB) and of simple ventricular premature beats (VPB) in very old subjects undergoing dynamic ECG for 24 h. The 18 subjects under study (11 women and 7 men) were aged 90 or more (mean +/- SD 92.3 +/- 2.3, range 90-98), did not complain of acute cardiac pathologies, were not taking any medication and were synchronized as to time schedules. The mean duration of DECG recording was of 23 h and 54 min. The collection of data concerning the hourly mean of HR (6 ten-sec samples taken every 10 min) and of the number/hour of APB and VPB was carried out manually. A significant rhythm (single cosinor) was detected for heart rate in 14 subjects out of 18 and in the group (population cosinor); it was also detected for APB (9 subjects out of 15) and for VPB (5 subjects out of 15) also by the single cosinor. It was not detected for the group (population cosinor). No significant correlations, either direct or inverted, were revealed between HR and premature beats. We demonstrate therefore that, even in very old subjects, the circadian rhythm of HR still exists as in younger subjects.

Aged↗
PubMedDate not supplied

A chronomorphological structural model of rat thyroid gland.

Circadian rhythmicity of the structural morphometric model of thyroid has been studied in 36 Wistar rats kept in LD 12:12. The parameters evaluated are: a. the volume fraction occupied by: 1. follicle epithelium, 2. colloid, 3. interstitium at 6 time points in 24h; b. the follicle size distribution; c. the number of follicles per unit tissue volume. The circadian rhythms of mean follicular diameter and of follicular cavity mean diameter have been demonstrated (p less than 0.03 and p less than 0.01 respectively) and show overlapping acrophases of -120 degrees (-64 degrees/-176 degrees) and -108 degrees (-99 degrees/-116 degrees). The synchronization between rhythms, shown for mean follicular diameter and for follicular cavity mean diameter, suggests a rhythmical pulsation of the whole follicle, while the thickness of the follicular epithelium does not undergo a statistically significant periodic variation.

Animals↗
PubMedDate not supplied

Cefodizime administration in healthy subjects: studies of natural killer cells, urinary hormones and electrolytes.

Two studies are here discussed: the first one on changes of the natural killer cell activity of PBM cells exposed in vitro to CDZ and the second one on urinary electrolytes, cortisol, aldosterone and DHEA-S circadian rhythms, evaluated in healthy subjects who received a single dose (2 g i.v.) of cefodizime (CDZ). The effect of CDZ in health includes a reduction of the circadian amplitude of natural killer cell activity. With the methods used, no difference was found between placebo and CDZ, as far as circadian rhythms of urinary electrolytes, cortisol, aldosterone and DHEA-S are concerned.

Adjuvants, Immunologic↗
PubMedDate not supplied

Elliptic Fourier analysis of mandibular shape.

Craniofacial growth and development involve both size and shape variations. Shape variations can be assessed independently from size using mathematical methods such as the elliptic Fourier analysis, which allows a global evaluation of the shape of organs identified by their outlines independently from size, spatial orientation, and relation to reference planes. The mandibular outlines were digitized from the tracings of the Bolton standards (lateral view) from 1 to 18 years of age, and the age differences in shape independently from size were quantified using the elliptic Fourier series. A "morphologic distance" MD (i.e., a measurement of differences in shape) between each younger mandible and the oldest one was computed using the relevant Fourier coefficients like the cartesian coordinates in standard metric measurements. MD equals 0 when the profiles are identical. MD (Y) between the Bolton standard at 18 years of age and all the other Bolton tracings were significantly correlated (correlation coefficient r = 0.987, P < or = 0.001) with age (X) (semi-logarithmic interpolation Y = -3.87.log(e) X + 13.593). Differences between the size-independent shape of the Bolton standard at 18 years and the relevant plot at 1 year were located at the chin, gonion, coronoid process, anterior border of the ramus. Size differences were measured from the areas enclosed by the mandibular outlines. Mandibular area (Y) increased about 2.58 times from 1 to 18 years of age (X) (Y = -0.071.X2 + 4.917.X + 35.904, r = 0.997, P < or = 0.001). The shape effect was largely overwhelmed by the very evident size increments, and it could be measured only using the proper mathematical methods. The method developed could also be applied to the comparison between healthy and diseased individuals.

Adolescent↗
PubMedDate not supplied

Soft tissue facial morphology related to headform: a three-dimensional quantitative analysis in childhood.

The object of this investigation was to determine whether children of the same age with different headforms differ in their three-dimensional soft-tissue facial characteristics. The three-dimensional coordinates of 22 standardized facial landmarks were automatically collected in a sample of 70 boys and 71 girls age 11 to 13 years attending a junior high school. From the collected landmarks, several three-dimensional facial angles, linear distances, linear distance ratios, and volumes were calculated. For each subject the cephalic index (maximal head breadth/ maximal head length x 100) was computed and three groups of measurements for each sex were obtained (dolicho-, meso- and brachycephalic). A two-way factorial analysis of variance compared the effects of sex and headform, and the interaction sex x headform. On average, boys had significantly (P < or = 0.05) longer and wider faces than girls, with a larger lower third facial volume relative to middle third facial volume. A significant (P < or = 0.05) effect of headform over facial morphology was found for all angles with a prevalent axial orientation. Conversely, no effect was demonstrated for angles with a sagittal orientation, nor for any other considered parameters. For each sex, the dolichocephalic children had smaller values than the brachycephalic children (i.e., more convex faces in the left-right direction), while the mesocephalic children had intermediate values. No sex x headform interactions were found. Results confirm that a different headform (skull) is associated with a different three-dimensional facial morphology (combined effect of skull and soft tissues), but without size differences.

Adolescent↗
PubMedDate not supplied

Femoral asymmetry in healthy adults: elliptic Fourier analysis using computerized tomographic scout views.

Morphology (both size and shape) of paired structures differ in the left and right sides of body. Size and shape characteristics should be analyzed separately to supply information about the normal variations of human organs. In the present study, the within-subject size and shape asymmetries of normal human femur were analyzed from a mathematical standpoint. On the standardized frontal computerized tomographic scout views of both thighs of 14 healthy adults (7 women and 7 men aged 22-26 years), the outline of the femur was identified, and its size and shape were separately quantified. The left and right femur of each subject were compared, and size and shape asymmetry separately quantified on an intra-subject basis. Subjects were also grouped for sex, and mean values computed. Within-subject symmetry in femoral size and shape was high, with coefficients of superimposition ranging between 91% and 96.5%. In women, a slightly higher symmetry (up to 99.9%) was observed when the femoral outlines were standardize for size. Moreover, in the same group the asymmetry in the form of femoral outline seemed to be partly related to the asymmetry in femoral length. Conversely, no similar relations were found in men.

Adult↗