Three-dimensional reconstruction of the Meissner corpuscle of man, after silver impregnation and immunofluorescence with PGP 9.5 antibodies using confocal scanning laser microscopy

The 3-dimensional organisation of the neural component of the human Meissner corpuscle was studied after silver impregnation and following immunofluorescence for protein gene product 9.5 (PGP 9.5) by confocal scanning laser microscopy. The morphology of the Meissner corpuscle was found to show consistent differences depending on the labelling method used. After silver impregnation by the Winkelmann technique the branches of the afferent nerve fibres of the corpuscle showed both thin regions and varicose elements, the latter probably corresponding to the portions rich in mitochondria observed by transmission electron microscopy. The bulkier elements were never more than 5-6 microns in diameter. After immunolabelling for PGP 9.5 the nerve fibre branches in the corpuscle always presented flattened and discoidal expansions with a diameter of up to 30 microns. On the basis of what is known as to the mechanism of action of silver impregnations it is considered that the black precipitate preferentially labels the parts of neurons that are rich in neurofilaments. In any case the precipitate is deposited throughout the neuronal cytoplasm except in the mitochondria and the nucleus. Accordingly, in the varicosities of the Meissner corpuscles that are rich in mitochondria, there is little space for the formation of the precipitate. The use of antiserum against PGP 9.5, which labels the larger proteinaceous component of the axoplasm, demonstrates the complete architecture of the neural component of the Meissner corpuscle, and visualises the discoidal and flattened expansions which are absent in the impregnated corpuscles. It is concluded that immunostaining provides images of the corpuscles, and of peripheral neural structures that are in general closer to reality.

Improved minimally-invasive assessment of penile haemodynamics: the combination of colour Doppler sonography and injection-stimulation test

The aim of this study was to assess the diagnostic value of erotically enhanced penile colour Doppler sonography as a minimally invasive tool to evaluate penile haemodynamics. Colour Doppler sonography was used to study the cavernosal arteries of 135 consecutive impotent patients after intracavernous injection of a vasoactive mixture (injection phase) and after subsequent genital and audiovisual sexual stimulation (stimulation phase). The erectile response was upgraded after the adjunct of genital and audiovisual stimulation in 36% of patients. Colour Doppler assessment performed after the stimulation phase identified 16% of patients as arteriogenic despite normal erections, and 7% of patients falsely diagnosed as venogenic after the injection phase. When colour Doppler sonography and the injection-stimulation test are performed together as a single diagnostic procedure the overall diagnostic accuracy is significantly enhanced.

L'idea per una ricerca clinica: An idea for clinical research

An idea for clinical research mostly springs from personal clinical experience. Attentive reading of scientific reports and attending congresses with a high scientific content provide further food for thought. Research material must be critically assessed to make sure it contains something of real scientific interest.

A quale giornale inviare un lavoro scientifico: Sending a scientific paper to which journal?

After having carefully examined research results, the next problem is to decide which urological, medical or surgical journal to send the work to. Having chosen the journal, it is then essential to observe the layout and style requested.

A three-dimensional evaluation of human facial asymmetry

Soft-tissue facial asymmetry was studied in a group of 80 young healthy white Caucasian adults (40 men, 40 women) with no craniofacial, dental or mandibular disorders. For each subject, the 3-dimensional coordinates of 16 standardised soft-tissue facial landmarks (trichion, nasion, pronasale, subnasale, B point, pogonion, eye lateral canthi, nasal alae, labial commissures, tragi, gonia) were measured by infrared photogrammetry by an automated instrument. The form of the right and left hemifaces was assessed by calculating all the possible linear distances between pairs of landmarks within side. Side differences were tested by using euclidean distance matrix analysis. The mean faces of both groups were significantly asymmetric, i.e. the 2 sides of face showed significant differences in shape, but no differences in size.

A simple method for overcoming some problems when observing thick reflective biological samples with a confocal scanning laser microscope

A simple device is described, which allows the range of depth of scanning to be reduced when observing thick reflecting biological samples with a confocal scanning laser microscope (CSLM). Thick histological sections of human skin and rat brain stem were mounted between two coverslips ('sandwich' style) and the optical tomography was performed from both sides by turning the 'sandwich' upside-down. The samples were impregnated using standard Golgi-Cox, 'rapid Golgi' or other silver methods. The ability to turn the 'sandwich' upside-down is particularly useful when the reflective structure inspected is deep inside the section, i.e., near the lower surface of the specimen, or when it is opaque to the laser beam or excessively reflective.

Effect of yohimbine-trazodone on psychogenic impotence: a randomized, double-blind, placebo-controlled study

OBJECTIVES

The aim of this study was to determine the effectiveness and safety of yohimbine and trazodone used together for the treatment of pure psychogenic impotence.

METHODS

Sixty-three patients who had psychogenic impotence diagnosed on the basis of sexual history, results of physical examination, laboratory analysis, polysomnographic recording of nocturnal erections, and dynamic color Doppler sonography of the cavernosal arteries were entered into a randomized, double-blind, placebo-controlled, partial crossover study comparing placebo with yohimbine (15 mg per day orally) and trazodone (50 mg per day orally) used together. Treatment consisted of two 8-week courses. Patients who initially received placebo for 8 weeks were then switched to the 2-drug combination for 8 weeks. Erectile function, ejaculation, interest in sex, and sexual thoughts were investigated at the end of drug treatment and at 3- and 6-month follow-up. For statistical analysis chi-square, McNemar, and Student's t test for unpaired data were used.

RESULTS

Fifty-five patients (87%) completed the whole treatment schedule. Positive clinical results (complete and partial responses) were obtained in 39 (71%) patients at the end of the drug treatment phase. These results were significantly better than those obtained with placebo (p < 0.01). Positive results were maintained in 32 (58%) and 31 (56%) patients at 3- and 6-month follow-up, respectively. Minor drug-related adverse effects occurred in 6 (11%) of the patients in the yohimbine-trazodone group and in 2 (4%) in the placebo group.

CONCLUSIONS

The combination of yohimbine and trazodone is a safe and effective first-line treatment for psychogenic impotence.

Central and peripheral nervous structures as seen at the confocal scanning laser microscope

Central neurons and peripheral nervous structures, e.g. cutaneous free endings, perifollicular nets, Meissners corpuscles and intramuscular fibres, were studied using various impregnation methods. The confocal scanning laser microscopes (CSLMs) used were equipped with different laser sources, in order to evaluate their limitations and advantages with these techniques and to contribute to a better understanding of the general morphology of the nervous system. When staining with silver sections with clouds of tiny silver granules which are beyond the resolution power of the conventional light microscope but which show a high reflectivity with the CSLM are obtained. Golgi-Cox mercuric impregnation, however, provides specimens which are precipitate-free, thus ensuring the reliability of information obtained. It does, however, have the disadvantage of being applicable only to the central nervous system. In all cases it is an advantage for the instrument to be fitted with different lasers (e.g. Ar and He-Ne), so as to optimize the images of samples impregnated with different methods. Notwithstanding the possibility that artefacts may distort the geometry of the sample and reduce the resolution, the images presented in this paper show that with careful selection of optical sectioning distances, the use of a suitable stack of sections and, if necessary, the aid of false electronic colours and of partial or complete rotation, it is possible to achieve a more precise interpretation of the morphology and organization of complex structures, such as those of the nervous system.

Head posture and cephalometric analyses: an integrated photographic/radiographic technique

A photographic technique for natural head posture (NHP) recording that can be associated to standard radiographic exposures is presented. It allows the evaluation of radiographs, according to both the standard intracranial references and NHP. On the NHP photograph, the angle between the soft tissue nasion-pogonion line and the true vertical is calculated, and this value is used to rotate the standard radiograph around the Bolton point. The technique has been applied to 40 private orthodontic patients (24 females and 16 males, aged 7 to 20 years, mean 12.9 years). The hard tissue Frankfurt plane in NHP showed a wide variation: 80% of the patients had orbitale lower than porion (mean angle -6 degrees relative to the ground), 20% had orbitale higher than porion (mean angle 4 degrees). The position of this plane in NHP seemed to be different in the two sexes, with more males having the Frankfurt plane going upwards than females. The soft tissue Frankfurt plane (tragus-orbitale) in NHP was directed upwards (head extended) in 53% of patients. The two Frankfurt planes were never coincident in all subjects; the tragus was always lower and more anterior than porion. On average, the angle tragus-orbitale-porion was about 6 degrees. In young orthodontic patients NHP is therefore highly variable, gender dependent, and cannot be deduced from mean population values. Nevertheless, the evaluation of head position should be performed in each young patient before and during the treatment, to verify how the combined effects of therapy and growth act.

Mathematical definition of the shape of dental arches in human permanent healthy dentitions

Dental arch shape was studied in 50 men and 45 women aged 20-27 years with sound dentitions. Maxillary and mandibular arches were reconstructed by a fourth-order polynomial and a 'mixed' elliptical (anterior teeth), plus parabolic (post-canine teeth) interpolation of buccal cusp tips (central incisor to second molar). The maxillary arch resulted wider than the mandibular arch regardless of gender. Gender differences were found especially in the maxillary arch, where they reflect more a size discrepancy than a shape difference. The polynomial interpolation allowed the evaluation of arch asymmetry, which resulted negligible in all the subjects. The elliptical plus parabolic interpolation gave mean plots which were well superimposable to the ones obtained by the polynomial interpolation. These curves are geometrically simple and can be used for the mathematical description of dental arch shape in non-patient subjects. Moreover, they allow separate analysis of teeth with a different functional meaning.

Clinical reliability of multi-drug intracavernous vasoactive pharmacotherapy for diabetic impotence

The aim of this study was to assess the effectiveness and safety of intracavernous injections of a four-drug vasoactive mixture in diabetic patients with organic impotence. A group of 60 diabetic patients with either pure neurogenic, pure vasculogenic or mixed neurovasculogenic impotence were treated with intracavernous injections of a combination of 12.1 mg/ml papaverine hydrochloride, 1.01 mg/ml phentolamine mesylate, 10.1 micrograms/ml prostaglandin E1 and 0.15 mg/ml atropine sulphate ('full-dose' mixture). A mixture of the same drugs but at one-third concentrations ('reduced-dose' mixture) was also used. The mean (+/- SEM) volumes of the full-dose and reduced-dose mixtures used were 0.21 +/- 0.03 ml and 0.31 +/- 0.02 ml, respectively. All the patients were able to sustain a rigid erection at the end of the titration phase of the study. At a mean follow-up of 18 months, 48 patients (80%) were successfully using the mixture, 6 patients (10%) were using the mixture at a dose lower than the initial dose and 6 patients (10%) had dropped out from the injection therapy. No major complications were seen. The association of multiple vasoactive drugs which use different mechanisms of action, thus exerting a pharmacological synergism, is an effective and safe procedure in intracavernous pharmacotherapy for diabetic patients with organic impotence.

Vascular abnormalities in Peyronie's disease: the role of color Doppler sonography

We attempted to clarify the role of color Doppler sonography in assessing the vascular function of untreated Peyronie's disease. A total of 50 patients with a mean 20-month history of penile curvature underwent color Doppler sonography with the penis in the flaccid state and after intracavernous injection of 20 micrograms. prostaglandin E1. Of the patients 41 (82%) complained of various degrees of erectile dysfunction, while 9 (18%) reported sustained rigid erections. Pathological peak systolic flow velocities (less than 30 cm. per second) of the cavernous arteries were found bilaterally in 10 patients (20%) and unilaterally in 10 (20%). Peak systolic flow velocity correlated positively with cavernous artery flow volume and with acceleration. Cavernous artery end diastolic velocity and resistance index, measured 15 and 30 minutes after vasoactive injection and genital manipulation, were indicative of corporeal veno-occlusive dysfunction (greater than 10 and less than 0.75 cm. per second, respectively) in 32 patients (65%). Of these patients, 11 (22%) had mixed arteriovenous dysfunction and 9 (18%) had normal cavernous artery flow velocities. Flow along the cavernous arteries is sometimes altered in cases of Peyronie's disease while corporeal veno-occlusive dysfunction seems to be the main hemodynamic abnormality. Color Doppler sonography should be considered as the initial step in the diagnostic evaluation of patients with Peyronie's disease who may be eligible for surgical treatment.

Maxillary versus mandibular arch form differences in human permanent dentition assessed by Euclidean-distance matrix analysis

Euclidean-distance matrix analysis (EDMA) was used to analyse the dental arch form in 50 men and 45 women aged 20-27 yr with sound dentitions. Fourteen landmarks, corresponding to the centres of gravity (centroids) of the occlusal surfaces of all permanent teeth (right second molar to left second molar), were identified on the dental casts of subjects. All the possible linear distances between pairs of teeth were computed and maxillary/mandibular arch differences within sex were tested by EDMA. In both sexes, the maxillary arch was larger than the mandibular arch; arch shape was also significantly different. All teeth contributed to the shape difference between arches regardless of gender. EDMA also separated the influence of anterior and posterior teeth in the determination of upper/lower arch characteristics.

A three-dimensional study of sexual dimorphism in the human face

The sexual dimorphism in three-dimensional facial form (size plus shape) was investigated in a sample of 40 men and 36 women by using Euclidean-distance matrix analysis. Subjects ranged in age from 19 to 32 years, had excellent dentitions, and had no craniocervical disorders. For each subject, 16 facial landmarks were automatically collected using a computerized system consisting of two infrared CCD cameras, real-time hardware for the recognition of markers, and software for the three-dimensional reconstruction of landmarks' x, y, z coordinates. Euclidean-distance matrix analysis confirmed the well-known size difference between adult male and female faces (men's faces being 6% to 7% larger than women's faces), while it demonstrated no significant gender differences in three-dimensional facial shape. This result contrasted with the shape differences previously found when separate two-dimensional frontal and sagittal plane projections were analyzed. It could be explained by a relative three-dimensional compensation between the different facial dimensions.

Significance of full nocturnal erections with short duration

The aim of the study was to clarify the pathophysiologic significance of full but short-lived nocturnal erections observed in some impotent men. Penile circulation was assessed by color Doppler sonography and pharmacocavernosometry in 35 impotent patients who underwent polysomnographic recording of nocturnal erections. In each case, there were at least 3 erectile episodes with a complete rigidity (always > 700 g) but with a short duration (mean duration of the maximum level of full erection = 4 min; always < 6 min). All patients demonstrated a normal arterial inflow with mean +/- SEM right and left cavernosal peak flow velocities of 39.5 +/- 1.8 and 41.3 +/- 1.5 cm/s, respectively. Pharmacocavernosometry detected a dysfunction of the cavernous veno-occlusive mechanism (mean +/- SEM maintenance flow: 45 +/- 8 ml/min and mean +/- SEM corporal pressure decay over 30 s: 82.5 +/- 9 mm Hg) in 18 patients (51%). In these patients, this finding may be a possible explanation for the short duration of nocturnal erectile episodes. In the remaining 17 patients (49%) with normal penile vascular status, a dysfunction of the adrenergic system could play a role in the pathophysiology of this picture. Full but short-lived nocturnal erections, as assessed by polysomnographic recording, are indicative of a normal arterial status and should encourage further assessment of the corporal veno-occlusive mechanism.

Sexual dimorphism in the human face assessed by euclidean distance matrix analysis

The form of any object can be viewed as a combination of size and shape. A recently proposed method (euclidean distance matrix analysis) can differentiate between size and shape differences. It has been applied to analyse the sexual dimorphism in facial form in a sample of 108 healthy young adults (57 men, 51 women). The face was wider and longer in men than in women. A global shape difference was demonstrated, the male face being more rectangular and the female face more square. Gender variations involved especially the lower third of the face and, in particular, the position of the pogonion relative to the other structures.

Effectiveness and safety of multidrug intracavernous therapy for vasculogenic impotence

A four-drug vasoactive mixture (papaverine hydrochloride, prostaglandin E1, phentolamine mesylate, atropine sulfate) was used for intracavernous injection therapy in 94 patients with vasculogenic impotence as diagnosed by color Doppler sonography and dynamic infusion cavernosometry-cavernosography. At a mean follow-up of twenty months, 66 patients (70%) are using the injections with the initial dose and are satisfied; 14 patients (15%) are using the injections with a smaller dose than initially given; and 14 patients (15%) dropped intracavernous treatment. Only 4 patients (4%) were unable to achieve a sustained rigid erection during the mixture titration phase. Selected cases of vasculogenic impotence can be safely and effectively treated by the association of drugs which rely on different mechanisms of action, producing a pharmacologic synergism which enhances the overall therapeutic effect.

Real complete three-dimensional reconstruction of Golgi-impregnated neurons by means of a confocal laser scanning microscope

Golgi-impregnated neurons of the human or animal central nervous system were studied with a confocal laser scanning microscope (CLSM). The scanning properties (optical sectioning of the specimen) offered by the CLSM and the capacity of metal granules to reflect the laser beam allow a three-dimensional reconstruction of the impregnated neurons. The volume scanned can be depicted in three different ways: (a) extended focus, i.e., a bidimensional image that contains information from all the optical sections, as if there were an extensive depth of focus; (b) a topographic representation in which the intensity of every pixel is proportional to the calculated z value (as a result, the closer the object section is to the surface, the greater the color intensity becomes); and (c) shadow representation, i.e., a pseudo-three-dimensional image. In addition, a true and complete three-dimensional reconstruction of neurons can be obtained using an extended RAM and quick elaboration (fast CPU) combined with the rotation of the reconstructed image in the different planes. High-magnification, high-numerical-aperture (NA) oil immersion objective lenses with reduced working distance may present some problems in the three-dimensional reconstruction of large neurons with extensive and spreading dendritic branches. This limitation may be overcome by using a low-magnification (10 x) oil immersion lens.

Electromyographic activity of human masticatory muscles in normal young people. Statistical evaluation of reference values for clinical applications

Electromyographic activity of anterior temporal and masseter muscles was measured in 92 young healthy men and women with sound dentitions during rest position, contact in centric occlusion and clench. Male and female mean potentials were similar except in clench, where males had higher electromyographic levels. Mean pooled electromyographic potentials were 1.9 microV (TA) and 1.4 microV (MM) during rest position, 6.5 microV (TA) and 2.8 microV (MM) during contact in centric occlusion. Mean maximum voluntary clench potentials were 181.9 microV (TA) and 216.2 microV (MM) in men, 161.7 microV (TA) and 156.8 microV (MM) in women. Examined muscles were more asymmetric at low electromyographic activity (rest and centric occlusion) with the temporal muscle less asymmetrical than the masseter. In females temporal muscle activity tended to dominate at every contraction level, while in males masseter activity was stronger in clench, and temporal activity in centric occlusion and in rest position.

Craniofacial morphometry by photographic evaluations

Frontal and lateral oriented profile photographs of 108 healthy young adults (57 men and 51 women) were taken, and a standardized protocol was used to quantitatively describe the depicted craniofacial soft tissue structure, the relationships among facial structures, and head posture relative to the ground. Pictures were taken in two body positions, standing and sitting. The male faces were, on average, wider and longer than the female faces, in both frontal and lateral views, with greater differences in the mouth and chin regions. Both sexes were generally symmetrical. Persons who were asymmetric compensated for their appearance by changing head posture relative to the ground, so that in the frontal plane, the interpupillary axis and the occlusal plane were parallel to the ground. Measurements can be employed in computer graphic reconstructions used in orthognathic, maxillofacial, and plastic surgery. In the standing position, the Frankfurt plane was directed upward and forward, with a mean angle of 13 degrees relative to the ground. In seated subjects, it was more nearly horizontal (5 degrees in the men, 8 degrees in the women). This result confirms the need for a careful reevaluation of standard cephalometric and photographic protocols.

Human dental arch shape evaluated by euclidean-distance matrix analysis

Form differences between biological structures can be evaluated using several approaches. When landmark data are available, a recently proposed method (euclidean-distance matrix analysis) seems to be able to differentiate between size and shape differences. This method also localizes those areas which differ most between the two structures. We have applied it to analyze the sexual dimorphism in dental arch form in a sample of 50 men and 45 women. Subjects ranged in age between 20 and 27 years, and had sound dentitions. Fourteen landmarks, corresponding to the centers of gravity (centroids) of the occlusal surfaces of all permanent teeth (right second molar to left second molar), were individualized on the dental casts of subjects. All the possible linear distances between pairs of teeth were computed, thus creating four mean form matrices (one for each arch within sex). Gender differences were tested by using euclidean-distance matrix analysis. No significant differences were demonstrated in the shape of arches, while male arches proved to be slightly bigger than female arches.

Dental arch asymmetry in young healthy human subjects evaluated by Euclidean distance matrix analysis

Form differences between biological structures can be evaluated using several approaches. A recently proposed method (Euclidean distance matrix analysis; EDMA) seems to be able to differentiate between size and shape differences. Here it has been applied to study the asymmetry of mandibular and maxillary arches in 50 men and 45 women with sound dentitions. The centres of gravity (centroids) of the occlusal surfaces of all permanent teeth (right second molar to left second molar) were individualized on the dental casts of subjects. The form of the right and left maxillary and mandibular hemi-arches was separately assessed by calculating all the possible linear distances between pairs of teeth within arch and side. Side differences were tested by EDMA. In men, the maxillary and the mandibular arches were both symmetrical (i.e. there were no significant differences in size or shape between the left and right hemi-arches). In women, the mandibular arch was symmetrical, but in the maxillary arch the two antimeres had a significantly different shape. No size differences were found between the left and right female hemi-arches.

ANB skeletal types correlated to facial morphology: Euclidean distance matrix analysis

Pretreatment lateral skull radiographs of 145 patients aged 7 to 20 years are classified according to an ANB-angle reading corrected for the position of the maxilla and rotation of the jaw. The Euclidean distance matrix analysis is applied to compare the overall facial morphology between Classes I and II. This method differentiates between size and shape and localizes those areas that differ the most. Statistically significant different facial morphologies were demonstrated in the 32 patients aged 15 years or more. The younger patients with skeletal Classes I and II did not possess these different morphological characteristics. The results show that standard cephalometric classification criteria do not always correlate to actual differences in the overall facial morphology.

Human neonatal ovary: proposal of a three-dimensional model

A model of human neonatal ovary is presented, derived from morphometric, evaluations carried out on left ovaries removed from five full-term neonates with a 46, XX karyotype, free from malformations of the genital apparatus. According to this model, the gonad can be represented by a triaxial ellipsoid with a central medullary core surrounded by a cortical stratum of constant thickness. The germinal population, consisting of follicles and primitive cortical tissue, occupies the cortex, intermingled with the interstitium or stroma. In the cortex it is then possible to describe an outer layer formed by primitive cortical tissue, and an inner portion occupied by follicles. The primary and secondary follicles fill the portion near the medulla and the primordial ones are contained in the middle and outer zones. Since the variability observed among ovaries is slight, we can propose a mean model of neonatal ovary in which the spatial relationships among the different components, the total number of follicles and their position in the cortex can be calculated.

Kinesiographic three-dimensional evaluation of mandibular border movements: a statistical study in a normal young nonpatient group

Mandibular border movements were studied in a group of 74 healthy young men and women with sound dentitions and class I molar relationships. Movements were directly performed by the subjects and recorded with a mandibular kinesiograph, and slopes of the first millimeters of motion in the anterior and lateral guidances were calculated. In anterior guidance, the sagittal plane slope was steeper in men than in women, whereas the horizontal plane slope showed no gender differences. In the lateral guidances, frontal plane slopes were steeper in men than in women, with no side differences. The horizontal plane slope presented no side or sex differences. Most of the subjects demonstrated asymmetric guidances for both protrusive and the laterotrusive movements. These findings suggest that criteria for defining the norm should include asymptomatic asymmetry instead of strict morphologic symmetric appearance.