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Biomedical subjects

A Calligaro

Publications and source records attributed to A Calligaro.

At least 73 records · Page 4Linked to original sources
PubMed1989

Microscopic and ultrastructural study of the lymphatic system in the human parotid gland.

The localization and fine structure of the lymphatic system vessels are examined in the human parotid gland. A network of lymphatic capillaries extends in the intralobular connective septa around the striated ducts. These lymphatics converge in collectors frequently bordering the excretory ducts. On the contrary, no lymphatics are present next to the intercalated ducts and adhenomers. Ultrastructurally, the lymphatic capillaries are characterized by a very thin endothelial wall and by slightly complicated intercellular adhesions. Open junctions are also present. The presence of numerous lymphatic capillaries bordering the striated ducts and their blood microvasculature is discussed in relation to the functional activities of the striated ducts in the modification of the saliva.

Humans↗
PubMed1989

Morphometric data on the lymph capillaries of the ventricles of the rabbit heart.

A morphometric analysis was done on the lymph capillaries of both left and right ventricles from the rabbit heart. The measurements were made on the lymphatics identified in the subepicardium, myocardium and subendocardium of the ventricular walls. Quantitative evaluations were carried out on light and electron microscopic sections by a computerized image analysis system. The following parameters were selected and measured: (1) the diameter (of area-equivalent circle) of lymph capillaries, (2) the diameter of the uncoated micropinocytotic vesicles (located on the abluminal and adluminal side and in the cytoplasm of the endothelial cell) and the area occupied by the vesicles per unit area of cytoplasm. Differences in the size of the lymph capillaries were found in the three layers (subepicardium, myocardium and subendocardium) of the ventricular walls. The largest vessels were present in the subepicardium both in the left ventricle and in the right one. No significant variations were found in the lymphatics of corresponding regions on both ventricles. Little variations on the mean diameter of the uncoated micropinocytotic vesicles are present in the three regions of the endothelial wall. In the left ventricle only, the subendocardial vesicles are significantly larger than the subepicardial and the myocardial ones (p less than 0.05). The areal density occupied by vesicular system in the three layers of the ventricular wall showed significant differences in both ventricles (p less than 0.05). The vesicles present in the subepicardial vessels occupied the smallest areal density. No significant variations existed in the vesicular areal density between the two ventricles.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

[Immunocytochemical study of the development of the oral cavity in the rat].

Flow cytometry and autoradiography are extensively used for the evaluation of the number of cells in S-phase in order to study the proliferative activity within tissues and organs. The recent development of a monoclonal antibody against 5-bromo-2'deoxyuridine (BrdUrd), a nonradioactive thymidine analogue that is incorporated within DNA-synthetizing cells, allows the immunochemical detection of proliferating cells. The use of this antibody allows an immunocytochemical detection of proliferating cells "in situ" on tissue sections. We have applied this new technique for the identification of proliferating cells within the tooth and other organs of rat mouth during development. We believe that this technique, for its precision and simplicity, may be a powerful tool for studying the cytokinetic and the differentiation of normal and neoplastic cells within the mouth as well as in other districts of the body.

Animals↗
PubMed1988

Presence of phospholipidic lamellar bodies on the mucosa of rabbit eustachian tube. Ultrastructural aspects.

Electron microscopy of the rabbit eustachian tube showed the presence of osmiophilic lamellar bodies in the cytoplasm of secretory cells and of osmiophilic free lamellar membranes in the lumen of tubal glands or above the epithelium. Similar structures have been reported in other parts of the respiratory system and in the pulmonary alveoli. The functional significance of these morphological observations is suggestive of a surface-tension-lowering effect on the mucosal lining layer of the eustachian tube and of a possible relationship to the phospholipid surfactant of the lung.

Animals↗
PubMed1988

Lymphatic system in human dilated cardiomyopathy.

Lymph capillary features have been investigated in human hearts from subjects affected by dilated cardiomyopathy. The edematous myocardial regions present dilated lymph capillaries with a slightly indented endothelial wall. The intercellular adhesions are not especially intricate; the open junctions between contiguous endothelial cells are more numerous than in normal conditions. In the myocardial areas affected by interstitial fibrosis the lymph capillaries are scanty and subtle. The morphological features, evident in the edematous and the fibrotic regions of the hearts affected by dilated cardiomyopathy, are compared with those induced in the myocardium by damaging the lymph flow experimentally. Our observations suggest a differential response of the lymph system to modified conditions of the tissue and the interstitium.

Cardiomyopathy, Dilated↗
PubMed1988

An immunocytochemical method for studying embryo cytokinetics.

The immunocytochemical detection by a monoclonal antibody of bromodeoxyuridine incorporated into S-phase cells allows the identification of proliferating cells. In this study we demonstrate that the labelling of embryo tissues is achieved by a single administration of BrdUrd to the mother after a 1 hour-labelling period. This simple and rapid technique facilitates the detection of proliferating cells within the embryo for the study of developing tissues and embryo cytokinetics.

Animals↗
PubMed1987

Influence of fibronectin on the fibrillogenesis of type I and type III collagen.

The in vitro self-assembly of type I and type III calf skin collagen in the presence of fibronectin was studied turbidimetrically. Fibronectin delayed the fibrillogenesis of type III collagen but accelerated that of type I collagen. The effect of fibronectin was concentration-dependent. The lag phase was more altered than the growth phase in the presence of fibronectin while the final turbidity and the amount of fibrils formed were unmodified. Fibrils obtained in the presence of fibronectin all showed native banding pattern. Fibronectin bound partly to collagen fibrils; the amount of bound fibronectin was similar for the two types of collagen and tended to be constant at increasing fibronectin concentrations. It is suggested that the antithetic effect of fibronectin on type I and type III collagen fibrillogenesis may arise both from the different affinity of fibronectin to the two types of collagen and the different aggregation properties of each collagen type.

Animals↗
PubMed1987

Ultrastructural study of the adjoining areas between the endothelial cells of the rabbit heart lymph vessels.

The transendothelial transport across the lymph vessel wall is connected to the morphological and ultrastructural features of the lymph vessel endothelium. In the present study the lymph vessel wall and the adhesion areas between contiguous endothelial cells of the rabbit heart were examined also by means of serial sections. This examination allowed us to reconstruct the whole intercellular connecting areas and to clarify some discussed adhesion structures. The adjoining cells are connected by three types of contact: end to end, overlapping and interdigitation. In addition the cellular processes form intraendothelial, tortuous channels with focal specialized junctional areas. Only occasional open junctions are present. Our features are discussed and compared with the sometimes conflicting literature data on the morphological properties of these adjoining areas for their significance in the mechanisms of lymph formation.

Animals↗
PubMed1986

Decrease of hepatic mitochondrial glutathione and mitochondrial injury induced by 1,2-dibromoethane in the rat in vivo: effect of diethylmaleate pretreatment.

Diethylmaleate (DEM) potentiated the 1,2-dibromoethane (DBE)-induced hepatic morphological lesion in fasted male Wistar rats, as revealed by light and electron microscopy examination. The subcellular structures involved in such lesions were the mitochondria. The potentiating effect of DEM appeared to be due to enhancement of the depletion of hepatic mitochondrial glutathione (GSH) caused by DBE. DEM, however, failed to potentiate the DBE-induced release in the plasma of hepatic enzymes. The relationship between loss of mitochondrial GSH, mitochondrial injury, and the importance of the mitochondrial lesion in DBE-induced hepatotoxicity is discussed.

Animals↗
PubMed1986

Lymph vessels of the rabbit heart: distribution and fine structure in atria.

The distribution and fine structure of lymph capillaries in the atria of the rabbit heart were examined. A lymph capillary network extends into both the right and left atria but its distribution is not uniform. It is developed in the subepicardium but not in the myocardium and subendocardium of the atrial wall; overall it is less extensive than the corresponding network in the ventricles. In the atrial conduction system and in particular the sino-atrial node and the crista terminalis, the lymph network is more widely distributed; small lymph capillaries are also detected between the myocardial cells of the conduction system. A large lymph channel consistently runs along the medial side of the crista terminalis. The morphologic characteristics of atrial lymph capillaries include irregular shape, thinness of the endothelial wall, superimpositions and interlockings of the cells in the contact areas with complex junctional processes, thin and discontinuous basal membrane.

Animals↗
PubMed1986

Cytoplasmic bodies in lymphatic endothelial cell.

Although micropinocytotic vesicles and other large vesicular structures have been observed in lymphatic endothelial cells on electron microscopy, in this study ultrastructure attention was focused on a variety of other membrane-bounded structures in the cytoplasm of these cells in the rabbit heart. The first type was oval or round in transverse section and elongated in longitudinal section, was 100-200 nm in diameter and contained regularly spaced tubules. These features resembled rod-shaped bodies detected thus far only in blood vascular endothelial cells. A second type of cytoplasmic body was also frequently seen in lymphatic endothelium. It contained irregularly spaced small vesicles, 5-7 in number and 45 nm in diameter. A third type of vesiculated body was only occasionally found. This latter structure was greater than the previously described bodies and ranged from 3-5 micron in diameter, and filled with granular, inhomogeneous material and filamentous-like components. The functional significance of these intraendothelial bodies is as yet unexplained.

Animals↗
PubMed1986

The effect of corticosteroids on microvillous vesicles from the small intestine of adult rats: an automated, morphometric analysis.

The hypothesis that the corticosterone-induced enhancement of D-glucose uptake by brush-border membrane vesicles from the small intestine of adult rats is caused by an alteration in vesicle volume was tested by means of structural morphometric computerized analysis. By using a Ca2+ precipitation method, microvillous membrane vesicles were prepared from different groups of adult rats: normal controls; animals sacrificed 8 days after adrenalectomy; sham-operated pair-fed controls; animals treated with corticosterone (1 or 10 mg x 100 g b.wt.-1 daily i.p. for 8 days); corticosterone vehicle-treated controls. The vesicles were processed by conventional electron microscopy techniques. Morphometric computerized analysis was carried out on electron micrographs at a 20,000 x magnification, after selecting by an interactive method the vesicles showing certain morphologic features. The morphometric parameters determined for the vesicles from each experimental group were diameter, shape factor (minimal to maximal diameter ratio), surface area and volume. The following main findings were obtained: the vesicles were consistently spherical, with the glycocalyx on the outer side; sham-operation and pair-feeding with adrenalectomized rats, as well as corticosterone-vehicle injection, significantly reduced vesicular volume as compared to normal controls; adrenalectomy significantly decreased vesicular volume as compared to pair-feeding; excess of corticosteroids caused opposite changes (i.e. a significant increase of vesicle volumes as compared to vehicle injection), which were apparently dose-dependent. A comparison with D-glucose vesicular transport data previously obtained under the same experimental conditions revealed the existence of a positive relationship between vesicular volume and D-glucose half-filling time (t 1/2). A positive relationship between vesicular volume and D-glucose vesicular space was found for all experimental conditions except vehicle injection. As a whole, the morphometric results were consistent with functional findings, supporting our previous hypothesis that the corticosterone-induced increase in D-glucose transport by small intestinal microvillous vesicles is due, at least in part, to enlargement of the vesicle.

Animals↗
PubMed1986

Lymph vessels of the heart. A comparative study of various techniques for light and electron microscopy.

This investigation was carried out in order to find out which was the best technique, among those reported in the literature, to recognize the small lymph vessels by light microscopy, while at the same time allowing a good ultrastructural preservation of tissues. The study was performed with rabbit hearts according to the following methods: (1) injection of India ink into the wall of the heart followed by perfusion with aldehyde fixative; (2) injection of India ink into the wall of the heart followed by immersion in aldehyde fixative; (3) treatment of the animals with histamine dihydrochloride by e.v. route and aldehyde (4) fixation by immersion; (5) fixation by immersion in osmium tetroxide fixative; fixation by immersion in aldehyde fixative; (6) fixation by perfusion with the same mixture as in (5). In cases (1), (2), (3), (5), and (6), the tissue specimens were postfixed in osmium tetroxide according to conventional methods. The validity of the different methods was checked by examining semithin sections of varying thickness at the light microscope and ultrathin sections at the transmission electron microscope. A comparative examination of the preparation showed that the method allowing the promptest recognition of the small lymph vessels, together with the best ultrastructural preservation and a good reproducibility of results was perfusion of the coronary circle.

Animals↗
PubMed1985

Nuclear membrane-staining antinuclear antibody in patients with primary biliary cirrhosis.

An antinuclear antibody specific for nuclear membrane (ANMA) was observed by the immunofluorescence method in sera from patients with primary biliary cirrhosis (PBC). ANMA was present in 18 of 63 PBC sera (28.5) and in 1 of 431 control sera (0.2%). Its reaction appeared as a thin fluorescent ring confined to the nuclear envelope and was more evident when the sera were highly diluted and the fluorescence, due to frequently associated antimitochondrial antibody, faded. The ANMA fluorescent pattern was confirmed by indirect immunoperoxidase staining. ANMA was seen on both tissue cryostat sections and HEp-2 cells. It was a poorly or non-complement-fixing IgG, specific for an antigen resistant to DNase I, RNase, and trypsin. The significance of its presence in PBC in unknown at present. Identification of its antigen with one of the centromeric antigens is suggested.

Animals↗
PubMed1985

Association of anti-centromere and anti-Scl 70 antibodies in scleroderma. Report of two cases.

In testing for antinuclear antibodies the sera of 121 patients affected with scleroderma, we found in 2 of them the concurrent presence of anti-centromere and anti-Scl 70 antibodies. Since the association of these antibodies has never been reported, to the best of our knowledge, we report the clinical and serological features of the 2 patients. Both subjects were women with an incomplete CREST syndrome (RST), a relatively limited involvement of the skin, a mild pulmonary fibrosis without apparent signs of other visceral involvement. On the other hand, the clinical course of the disease was different in the 2 cases. One patient had a longer disease duration and up to date the clinical features appear to be unchanged; the other had a shorter disease duration, when suddenly she died of cardiac arrest.

Antibodies, Antinuclear↗
PubMed1985

Prevalence of anticentromere antibody in blood relatives of anticentromere positive patients.

Anticentromere antibody (ACA) was investigated in 116 blood relatives of 22 ACA positive patients affected with scleroderma and, for comparison, in 82 healthy subjects matched for age and sex who belonged to 25 families. No relative showed any evident scleroderma symptom although in 8 an unusual cold sensitivity of the extremities was present. ACA at a low titer (40), was found in 4 relatives (3.44%), while it was absent in control sera. The 4 ACA positive relatives were first as well as second degree relatives of probands. Two had familial disease: one idiopathic chronic hypoparathyroidism and the other mental retardation. The third had myasthenia gravis and the fourth unusual cold sensitivity and allergic dermatitis. At present we cannot explain the significance of ACA occurrence in relatives of ACA positive patients. Followup clinical and serological studies could show a possible association of low titer of ACA with subclinical scleroderma features in patients who later develop overt disease.

Adolescent↗