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Biomedical subjects

A Montella

Publications and source records attributed to A Montella.

At least 19 recordsLinked to original sources
PubMed2005

Cytomorphologic and ultrastructural study of nasal mucosa by means of brushing: a comparison between asymptomatic and rhinitic subjects.

The authors compared the cytomorphologic and ultrastructural features of nasal epithelium collected by means of brushing from asymptomatic subjects with these of patients affected by nasal polyposis (NP), allergic (AR) and non-allergic rhinitis (NAR). A brushing of nasal epithelium was taken from each member of both groups, and analysed under light and electron microscopy. The observation showed normal ciliary patterns and preserved intercellular joints in the great majority of asymptomatic subjects, while in all subjects of the pathologic group the junctions appeared variously damaged or absents, with ciliary abnormalities. The damage to the intercellular joints, rather than the alterations of ciliary patterns, seemed to represent in this study the border between the absence of symptoms and the presence of chronic inflammation. Therefore, a reduced tightness of the intercellular joints could contribute to the impairment of the mucociliary clearance, priming the vicious circle that leads to the condition of chronic inflammation.

Adult↗
PubMed2003

Identification of a mutant allele of the androgen receptor gene in a family with androgen insensitivity syndrome: detection of carriers and prenatal diagnosis.

We report the results of a molecular study of a large family segregating the complete form of the Androgen Insensitivity Syndrome (CAIS) in several family members from three generations. We identified the mutant allele by polymerase chain reaction (PCR) amplification of the short tandem repeat (CAG)n, highly polymorphic in the population, present in the first exon of the androgen receptor (AR) gene. In this family four different alleles were detected and one of these showed a perfect segregation with the disease. This study enabled us to identify the heterozygous females in this family. We think that this simple, indirect test, is also suitable for prenatal diagnosis of Morris' syndrome when the mother is heterozygous for the size of the short tandem repeat and one affected subject in the family may be studied.

Adolescent↗
PubMed2001

Ultrastructural anatomy of contracted capsules around textured implants in augmented breasts.

The development of a capsule around an implant is part of the physiological response to a foreign body. Capsular contracture is the most specific and frustrating complication of augmentation mammaplasty, and a lot of studies have been devoted to it. The aim of the current study is to examine the fine architecture of the contracted capsule around textured implants in humans. Eight capsules from augmented and contracted breasts with gel-filled, textured-surface silicone implants were studied after standard preparation for light and scanning electron microscopy, and after partial digestion in sodium hydroxide. Two capsules from contracted breasts around smooth implants and two noncontracted capsules around textured implants were prepared and studied in the same fashion as controls. A multilayer structure of the contracted capsule was seen, and the architecture of the various layers is described. The inner surface presents irregular craterlike depressions. The arrangement of collagen fibers varies in capsule layers. The effect of a textured-surface implant on the mechanism of capsule contraction based on the observed capsular architecture is that only part of the capsule is effective mechanically in producing a contracting force. A thin vascular layer was identified near the inner surface in contracted capsules around textured implants, and the authors' think that this layer is probably the key structure in the histological development and growth of the capsule.

Adult↗
PubMed2001

Syncytial units isolated from early human placentas.

This morphological study demonstrates that during the early phases of pregnancy, in the syncytium there are individual multinucleated units joined to one another by junctional complexes which probably are destined to flow together with the main syncytium by membrane breakdown. Normal human placentas from 6th to 12th week of pregnancy, derived from voluntary abortions, have been utilized. According to the method described by Tedde et al. (1991), clusters of villi have been isolated, washed in saline and subjected to a treatment with a 0.3% trypsin solution that caused the detachment of numerous cellular elements from the surface of the free villi. Such isolated elements have been subjected to centrifugation and separation in Percoll gradients. Then multinucleated syncytial units have been collected, attached to slides by cytocentrifugation, stained with toluidine blue, observed at the light microscope and utilized to count their nuclei: about 600 elements from different weeks of pregnancy have been considered and the results have been submitted to statistical analysis. The svncytial units are multinucleated and can often be different from one another, particularly in regard to the characteristics and the number of the nuclei. The evaluation of the number of nuclei contained in different syncytial elements shows that nuclei are less numerous in the early phases (6-8 weeks) and increase in number towards the end of the first trimester in a statistic significant way. In conclusion, the present study could confirm the existence of single syncytial units, joined to constitute the syncytial layer, probably destined to a complete fusion in the main syncytium and likely in functional relationship with the underlying Langhans cells.

Cell Nucleus↗
PubMed2000

Histogenesis and morphology of the flexor tendon pulley system in the human embryonic hand.

The number, position, structural and ultrastructural features of the flexor tendon pulley system in six human embryonic hands, aged from 6 to 12 weeks, were studied by light and electron microscope. The pulley system can be recognized from the ninth week; later, at 12 weeks, the structures are easily identified around the flexor tendon in positions closely correlated to those found during post-natal growth and in the adult hand. Structurally and ultrastructurally the pulleys are not simply thickened portions of the sheath. They are formed by three layers: an inner layer, one or two cells thick, probably representing a parietal synovial tendon sheath; a middle layer formed by collagen bundles and fibroblasts whose direction is mainly perpendicular to the underlying phalanx; and an outermost layer consisting of mesenchymal tissue with numerous vessels which extends dorsally in an identical layer, forming a ring that includes flexor and extensor tendons and the cartilaginous model of the phalanx. The pulley does not have a semicircular shape but a much more complicated one, owing to the middle layer which in part runs dorsally and in part ventrally, under the flexor tendons.

Gestational Age↗
PubMed1999

Persistence of bone collagen cross-links in skeletons of the Nuraghi population living in Sardinia 1500-1200 B.C.

Bone collagen has a specific molecular ultrastructure which can be proved by birefringence. This protein, forming the main organic component of bone tissue, is known to survive millennia in paleontological bones and teeth. Birefringence of bone collagen obtained from the skeletons of the Nuraghi population living in Sardinia c-ca 1500 years B.C. was found previously by the use of polarizing microscopy [1]. In this paper, using high pressure liquid chromatography (HPLC) techniques, we show the existence of bone collagen cross-links preserved in Nuraghi skeletons after more than 3000 years.

Amino Acids↗
PubMed1998

Responses of vestibular neurons to arginine vasopressin microinjection.

The aim of the present research was to evaluate the effects induced by arginine vasopressin (VP) microinjection on the electrical activity of single vestibular neurons. Experiments were performed on anaesthetized guinea-pigs in which the spontaneous and the evoked electrical activity of vestibular neurons were recorded before and after intranuclear VP microinjection (0.25.10(-5) pg VP in 0.25 microliter NaCl 0.9% solution). Results showed that VP microinjection affects the spontaneous as well as the evoked vestibular neuron activity. More precisely, 60% of 30 tested neurons were inhibited, 30% were excited and the remaining 10% were unaffected by VP microinjection. The changes in neuronal activity reported above were attributed to a direct action exerted by the polypeptide on vestibular complex neurons. The possible role played by VP in the mechanisms of postural control exerted by the vestibular system was considered as well.

Animals↗
PubMed1993

Blood and/or lymphatic connection of laryngo-pharynx and thyroid: an anatomic and clinical problem.

Three patients, undergoing surgery for pharyngeal carcinoma, were studied after their informed consence in the aim of ascertaining: 1) whether the routinary hemithyroidectomy in case of surgical treatment of the cancer of pyriform sinus is justified by a real probability of neoplastic invasion of the gland, and 2) which pathway the neoplasia follows in the metastatic process. In each patient a small amount of methylene blue solution was injected in the pyriform sinus submucosa, just before starting the surgical operation, currently including hemithyroidectomy. The stain spreads to the superior portion of the thyroid lobe, and seems to follow the periarterial lymphatic vessels. Even if further researches are necessary, the obtained data seem to justify routinary thyroidectomy in course of surgical treatment of the hypopharyngeal cancer.

Humans↗
PubMed1992

Morphological study of fetal nasopharyngeal epithelium in man.

In 30 human fetuses between 8 and 13 weeks of intrauterine life the lateral wall of the nasopharynx was examined by light microscopy and transmission and scanning electron microscopy. In the subjects between 8 and 9 weeks in utero the mucosa displays still an immature appearance, being mono- or bistratified and lacking the characteristic structures of the respiratory epithelium. Nevertheless, signs of differentiation are to be noticed, with the presence of two distinct cellular types that, in the later periods, will give rise to ciliated cells and microvillus-provided cells. An almost complete differentiation will be reached at 12-13 weeks in utero, even if goblet cells are still lacking in the examined zone during the considered period. Nonrespiratory types of epithelium, such as transitional or squamous, were never found in the studied subjects.

Embryonic and Fetal Development↗
PubMed1992

[The shape of the nasopharynx in youth: statistical study].

The particular shape of the nasopharynx in the child can influence morphology and physiopathologic behaviour of the mucosa. In such a perspective, it appeared interesting to evaluate the kind and the entity of its variations by means of nuclear magnetic resonance (NMR) in 50 patients (age range: 2 months-16 years). The results show that the nasopharyngeal shape (represented either by bending radius and shape factor) varies in a statistically significant way during the considered age range, while the dimension of the pharyngeal tonsil remains constant in the studied cases. The statistically significant shape variation of the tonsil appears, so, related to its involvement in the shape variation of the whole nasopharynx.

Adolescent↗
PubMed1992

Presence of antisperm antibodies in the serum of Sardinian adult people. II. Study on a selected infertile population in north Sardinia.

Among many possible causes of infertility an immunological factor must be considered, in particular the presence of antibodies to spermatozoa in the serum. In previous researches we confirmed the presence of antisperm antibodies in the serum of healthy men of North Sardinia in percentage equal to 2.4% of the considered population. The aim of the present study is to evaluate the correlation between the presence of antisperm antibodies and infertility. The presence of antispermatozoal antibodies has been evaluated in the serum of 124 men (aged 25-50) affected by unexplained infertility utilizing the indirect immunofluorescence and ELISA methods. The presence of antisperm antibodies has been found equal to 19.3% of the tested sera. These results show that the incidence of antisperm antibodies is higher in the serum of male partners from infertile couples than in healthy subjects (P < 0.01), also in a relatively segregated and pure population like the one studied.

Adult↗
PubMed1992

[Dimensions of the human aortic arch and thoracic aorta studied by nuclear magnetic resonance].

The size of the aortic arch and thoracic aorta was measured in 50 healthy volunteers studied by NMR. In each case the following parameters were measured and statistically elaborated: diameter (in mm) of ascending aorta (between onset and arch beginning), of aortic arch (intermediate zone), of isthmus, of descending aorta (between isthmus and diaphragm), of diaphragmatic isthmus; a mean diameter was also calculated, and for every diameter mean and standard deviation were obtained. Moreover, the length (in mm) of superior and inferior contours of the aortic arch, as the ratio of these two values were obtained. At last, total length of considered aortic tract, area of visualized surface and theoretic volume were obtained. For each parameter a diagram was then plotted, with age in ordinates and values of above mentioned parameters in abscissae. Statistical evaluation allows to affirm that the size of the aorta grows with ageing. On the contrary, the ratio between superior and inferior contour of the aortic arch tends to remain unvaried; this fact seems to disagree with the current opinion that the superior wall of the arch grows with age more than the inferior one.

Adolescent↗
PubMed1992

[Structural organization of the menisci of the human knee: scanning electron microscopy study].

The structure of the meniscus of the knee joint was studied in 10 human subjects after meniscectomy for acute trauma. The specimens were studied by scanning electron microscopy after cryofracture. Collagen fibres are arranged in two layers: a thin superficial zone with radially oriented fibres and a deep zone with circumferentially oriented ones. Deep fibres are surrounded by oblique fascicules. The cells are rare and oval-shaped. The observations enhance the hypothesis that the meniscus of the knee joint is not a real fibrocartilage.

Adult↗
PubMed1992

[Morphological characteristics of mastocytes in the infertile human testicle].

Mast cells, basophilic elements of the connective tissue, have been studied in numerous researches carried out both in man and animals. Previous studies showed that mast cells have been found in increased number in testis affected by pathology. In the present research morphologic characteristics of the mast cells in human infertile testis have been studied. Testicular biopsies obtained from 49 subjects, aged from 21 to 61 years, have been treated according to the current techniques for transmission electron microscopy. Results showed that it is possible to distinguish at least two types of mast cells: 1) "Interstitial" mast cells, large, round shaped, with great content of large characteristic granules, in relation with the loose connective tissue surrounding capillary vessels and Leydig cells; 2) "Peritubular" mast cells, flattened and relatively poor in granules, trapped in the conspicuous peritubular collagenic layers. These two types of mast cells differ from one another as concerns not only localization, but also general morphological characteristics and number and ultrastructure of cytoplasmic granules. Probably it is possible to establish a relationship between peritubular mast cells trapping and the increased deposition of fibrous connective tissue in the peritubular layers; such a deposition characterizes a lot of testicular pathologies.

Adult↗
PubMed1991

[Tartar and periodontal disease--a cofactor in etiopathogenesis].

Calculus may be considered as an aggregate of calcified deposits or deposits that are going to calcify in the oral cavity. From a topographical point of view calculus is classified in supragingival and subgingival calculus. Calculus is composed by inorganic (70-80%) and organic (20-30%) components. Calculus results from calcification of plaque and epithelial cells exfoliated from oral mucosae. Calcification phenomena (carbonic acid theory) are caused by a rapid fall down of salivary acidity when saliva springs out gland ducts. In fact in the mouth there is a lower pressure of carbon dioxide than in the gland ducts. From this fact results that calcium bicarbonate (dissolvable) becomes calcium carbonate (undissolvable) that forms, starting from nucleating particles, calcium carbonate crystals. Then calculus is one of the most important cofactors in the etiology and pathogenesis of periodontal disease: a) it favors plaque growth and stabilizes it to dental and periodontal tissues; b) it favors retention of food debris and hinders dental cleaning; c) it has endotoxins and lets them free slowly; d) it hinders periodontal recovery. From this study it results that scaling and root planing are one of the first steps in periodontal therapy.

Dental Calculus↗
PubMed1991

[The gastric mucosa of the human fetus. II. Ontogenesis of the gastric glands in the strict sense].

The ontogenesis of the gastric glands of the fundus-corpus zone (oxyntic glands), in 37 human foetuses ranging from 9 to 16 weeks of gestational age, has been studied by light and electron microscopy. At 9 weeks of age the gastric mucosa already shows numerous and well developed gastric pits. Between 9 and 12 weeks of age, the proliferation of the epithelial cells at the bottom of the gastric pits gives rise to the glandular buds; the glandular lumen comes out later, at 13-16 weeks of age. The differentiation of the epithelial cells in the developing oxyntic glands does not occur simultaneously; on the basis of their morphological distinctive features it is possible to distinguish four principal types of epithelial cells: the endocrine cells are already present at 9 weeks of age; the parietal cells appear at 11-12 weeks; whereas the mucous neck cells and the zymogen cells can be recognized from the 12th week. During the studied gestational period no morphological sign of active exocrine secretion of oxyntic glands has been observed.

Cell Differentiation↗
PubMed1990

[Morphological findings in cryptorchism in the adult male].

Cryptorchidism, the most common endocrine disturbance in the newborn, is still present in 0.3% of all postpubertal men as monolateral or bilateral condition. The undescended testis, in postpubertal age, is permanently damaged, so about 80% of cryptorchids are subfertile or definitively sterile. In the present study we relate our observations on structure and ultrastructure of testicular biopsies obtained from 29 cryptorchid men aged from 16 to 64. The individual pattern of morphological alterations is closely related to age and position of undescended testis. The following aspects are recognizable in cryptorchid testis: 1) seminiferous tubules reduced in size and irregular in shape; 2) tubular lumen occluded; 3) reduced germ cell population; 4) altered stages of spermatogenesis; 5) increased thickness of spermatogonia layer; 6) vacuolization of germ cells; 7) polynucleated germ cells; 8) acrosomal deformities; 9) delivery of immature germ cells; 10) Sertolisation of the seminiferous tubule; 11) immature Sertoli cells; 12) multilayered and thickened basement lamina; 13) peritubular fibrosis; 14) vascular fibrosis; 15) vacuolisation of Leydig cells; 16) interstitial mastocytosis. The findings present a mosaic of the morphological events, that are characteristic not only of the undescended testis but also of numerous testicular pathologies as well as of other conditions as prolonged hyperthermia, experimental ischaemia and senescence.

Adolescent↗