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A Modesti

Publications and source records attributed to A Modesti.

158 records · Page 9Linked to original sources
PubMedDate not supplied

An ultrastructural study of recurrent disc herniation: a preliminary report.

One early and two late recurrent herniations located at the same interspace as the original prolapse were studied by light and electron microscopy. In the early recurrent herniation, most chondrocytes appeared to be actively engaged in protein synthesis, and the intercellular matrix contained densely packed collagen fibers, numerous matrix vesicles, and abundant electron-dense amorphous material. In late recurrent herniations, chondrocytes had scant endoplasmic reticulum and extensive cytoplasmic filaments, and the intercellular matrix showed intermediate features between fibrocartilage and fibrous connective tissue. On the basis of these morphologic characteristics, it seems reasonable to assume that the newly formed disc tissue arose mainly from remnants of the original herniation in the early recurrent prolapse and from the annulus fibrous and the granulation tissue invading the disc space after discectomy in the late recurrent herniations.

Adult↗
PubMedDate not supplied

The expression of LEC/CCL16, a powerful inflammatory chemokine, is upregulated in ulcerative colitis.

Ulcerative colitis (UC) is a chronic inflammatory disease of unknown aetiology and pathogenesis. The presence in the colonic mucosa of reactive cells expressing proinflammatory cytokines and chemokines is associated with high levels of IL-10, an anti-inflammatory cytokine. Our aim was to investigate the role of IL-10 and the beta chemokine LEC/CCL16 selectively up-regulated by IL-10 in inflammatory cell recruitment and cytokine and chemokine production during UC. We studied histologically, immunohistochemically and ultrastructurally colonic biopsies from 20 active UC patients and 10 control specimens taken far from any macroscopically detectable lesion in age and sex-matched patients with noninflammatory bowel disease. In active UC, immature dendritic cells (DCs) in the LP are associated with IL-10 in the T cell rich area. Furthermore, most of the LP-infiltrating macrophages strongly expressed LEC/CCL16, a chemokine upregulated by IL-10. To evaluate if LEC/CCL16 plays a role in the inflammatory reaction present in UC, we performed morphological studies in mice injected s.c. with syngeneic tumor cells engineered to produce LEC/CCL16. We found that the LEC protein locally released by LEC-gene-transfected tumor cells is a potent proinflammatory chemokine that induces the recruitment of a reactive infiltrate, and an angiogenic process mirroring that in human UC.

Animals↗
PubMedDate not supplied

Immunity to extracellular matrix antigens is associated with ultrastructural alterations of the stroma and stratified epithelium basement membrane in the skin of Hashimotos thyroiditis patients.

Employing purified extracellular matrix (ECM) proteins, i.e. type I, III, IV and V collagens (CI, CIII, CIV, CV), laminin (LM) and fibronectin (FN), as antigen sources we detected autoantibodies to conformational and/or denatured ECM antigens among 34 of 50 sera obtained from Hashimotos thyroiditis (HT) patients and 6 of 51 control sera obtained from non-autoimmune thyroid disease patients and healthy donors (HT sera vs. control sera p=4 x 10-9). Reactivity to conformational antigens, mostly due to autoantibodies of the IgG isotype, was observed in 30/50 HT sera and in 6/51 control sera (p=3.5 x 10-7) and was not always concomitant with that to linear antigens, found in 23/50 HT and in 6/51 control sera (p=1.6 x 10-4). Ultrastructural analysis of skin biopsies obtained from 18 HT patients without symptomatic cutaneous diseases revealed defects of the stratified squamous epithelium basement membrane in 11/18, alterations of the stroma in 13/18 and both basement membrane and stromal defects in 9/18. Interestingly, 13/13 (p=0.012) and 9/11 (p=0.012) patients with stromal and basement membrane defects respectively, exhibited serum antibodies to at least one ECM antigen involved in the organization of the altered tissue compartment. Lastly, 10/18 skin biopsies presented immunoglobulin (Ig) and/or complement (C3) deposits along the cutaneous basement membrane zone (BMZ) or in the papillary dermis and 9/10 sera from the same patients simultaneously showed antibodies to at least one ECM antigen involved in the organization of these two skin compartments. Besides, 8/11 HT patients with basement membrane defects exhibited Ig or C3 deposits along the BMZ. Our findings suggest that autoantibodies to ECM molecules might contribute to the development of asymptomatic extra-thyroid skin diseases in HT patients.

Autoantibodies↗
PubMedDate not supplied

Insulin-sperm interaction: effects on plasma membrane and binding to acrosome.

In in vitro studies, viable, intact human spermatozoa took up free radioinsulin with an apparently non-receptor-mediated mechanism. However, when a colloidal gold-insulin complex was substituted for the radiotracer, no surface binding was visualized at the ultrastructural level. Upon sperm incubation in the presence of free insulin, a dose-dependent release of phospholipid phosphorus occurred, with a concomitant derangement of head cell membrane. After head membrane removal, spermatozoa-bound radioinsulin in a time- and concentration-dependent manner, the binding was displaceable by unlabeled insulin, and an exclusive localization of the colloidal gold-insulin complex was visualized at the acrosome level. On the basis of this evidence, both the plasma membrane and the acrosome seem to represent cytological targets for insulin.

Acrosome↗
PubMedDate not supplied

Basal lamina reduplication in malignant epithelioid pleural mesothelioma.

Malignant mesothelioma of the pleura is divided in three morphological variants: epithelioid, sarcomatous, and biphasic. Histological similarities between epithelioid malignant mesothelioma (EMM) and lung adenocarcinoma are responsible for the difficult differential diagnosis. Monoclonal antibodies are useful for distinguishing the two neoplasms through immunohistochemical phenotyping, although many cases require ultrastructural characterization for definitive diagnosis. In this study, transmission electron microscopic observations of EMM were compared with those of peripheral adenocarcinoma of the lung (PAL). More specifically, the morphology of the basal lamina is described in 23 cases of EMM and 12 cases of PAL. Reduplication of the basal lamina (RBL) was found in 11 cases (48%) of EMM and in none of the PAL cases. The same cases were immunostained for type IV collagen and the localization of this basement membrane component corresponded to the areas where basal lamina was observed. Since RBL has been associated with neoplastic differentiation in other tumors, this novel feature in EMM needs to be evaluated in future prognostic studies in malignant mesothelioma of the pleura. Moreover, RBL expression in EMM may be an additional ultrastructural parameter used in the differential diagnosis between EMM and adenocarcinoma.

Adenocarcinoma↗
PubMedDate not supplied

Changes in fibronectin production in rat liver during cirrhotic evolution due to treatment with CCl4 and steroid hormones: correlation with plasmatic fibronectin.

Previous our studies showed that some steroid hormones, as pure crystalline Progesterone (pPc) and 17-alpha-hydroxyprogesterone capronate (17 alpha HPC) heightened the cirrhogenic action produced in rat liver by carbon tetrachloride. Medroxyprogesterone (MPA), however, did not appear to promote cirrhosis, but increased just steatosis. In the present paper, we have studied the above mentioned steroid hormones for their possible capability of inducing changes in plasma fibronectin concentration. For this purpose, the soluble plasma fibronectin level was measured in female rats 45 days after CCl4-induced cirrhosis, and it was compared with the insoluble fibronectin of liver (detected by immunostaining) and the collagen content in the organ. The results obtained show that, after treatment with CCl4 and MPA, both plasma and liver fibronectin content strongly increases, whereas liver collagen content lowers. However, after treatment with CCl4 alone or in association with the other two steroid hormones, any changes in fibronectin content is not observable, but, on the contrary, is evident a heightened collagen production associated with a cirrhotic change of liver.

17 alpha-Hydroxyprogesterone Caproate↗
PubMedDate not supplied

The complete amino acid sequence of bovine skeletal muscle acylphosphatase.

The primary structure of bovine skeletal muscle acylphosphatase was determined by performing the sequence analyses of the complete series of tryptic peptides. The amino acid composition of the entire series of peptic peptides was used to reconstruct the sequence by the overlapping method. The proposed structure is further confirmed by analogy with known amino acid sequences of acylphosphatase from skeletal muscle of other vertebrate species. The length of the polypeptide chain is 98 residues, identical to the length of the enzymes from other known mammalian species, but different from that found in turkey. The enzyme is NH2-acetylated and a comparison with the analogous molecular forms from other vertebrate species indicates that there are several long polypeptide stretches strictly conserved (93-97% identical position among mammals, and about 80% between calf and turkey enzymes).

Acid Anhydride Hydrolases↗
PubMedDate not supplied

[The absence of the internal arms of dynein as a cause of the immotile cilia syndrome].

Two children aged 9 and 8 years respectively presenting upper and lower respiratory tract infections from early childhood are presented. In both, nasal mucociliary transport was impaired (greater than 30 min) and electron microscopic examination showed cilia devoided of the inner dynein arms. This ciliary defect is one of those recognized as a cause of the Immotile Cilia Syndrome but is very rare, having been described only once in a boy affected with Kartagener's syndrome, which in turn has been reclassified in the Immotile Cilia Syndrome. Therefore the absence of inner dynein arms observed by us in the respiratory cilia of these two children clearly indicated that similarly to many other genetic disorders the immotile cilia syndrome may be determined by many defects in the axonemal structure.

Child↗
PubMedDate not supplied

Nature and potential of the reactive response to mouse mammary adenocarcinoma cells engineered with interleukin-2, interleukin-4 or interferon-gamma genes.

A spontaneous mammary adenocarcinoma of BALB/c mice was transduced with the murine interleukin (IL)-2, IL-4, and interferon (IFN)-gamma genes. The ability of clones releasing IL-2, IL-4 or IFN-gamma to form tumors after s.c. challenge was compared to the TS/A parental cells (TS/A-pc) and to cells transduced with the neomycin resistance gene alone. Cytokine-gene-transduced clones activated a strong inflammatory reaction. The elicited by IL-2 and IL-4-gene-transduced cells efficiently led to tumor rejection. This reaction depended on the activation of several cell mechanisms, those classed as nonspecific being predominant. The repertoire of reactive leukocytes recruited in the reaction varies as a function of the secreted cytokine. The growth of a secondary contralateral TS/A-pc challenge after clone rejection was significantly impaired.

Adenocarcinoma↗
PubMedDate not supplied

Ultrastructural and immunohistochemical characterization of the tunica albuginea in Peyronie's disease and veno-occlusive dysfunction.

The tunica albuginea and corpus cavernosum from patients with Peyronie's disease (PD), patients with veno-occlusive dysfunction (VOD), and those from normal control subjects were studied by transmission electron microscopy and immunohistochemical staining for type I, III, and V collagens, platelet-derived growth factor (PDGF) AA and BB homodimers, and PDGF alpha and beta receptors. Ultrastructural modifications resembling a fibrotic reaction were detected in the two pathological tunica albuginea, but not in those from control subjects. Ultrastructural data demonstrated a general increase in fibrous and amorphous extracellular matrix material in the pathological tunica albuginea. The amorphous material probably represents glycoproteins and proteoglycans. The fibrous material, representing collagen, appears disorganized in the tissue and does not display the typical and homogeneous diameter, size, and spatial arrangement. Large areas of extracellular and intracytoplasmic, partially degraded, fibers are visible. An increased type I/III collagen ratio was detected by immunohistochemistry in the two pathological tunica albuginea. Moreover, a strong expression of type V collagen, correlated to fibroblasts, was revealed. Fibroblasts from control tissues, on the other hand, were totally negative. Finally, PDGF AA and BB were positive in fibroblasts from pathological tunica albuginea but were negative in control tissues. PDGF beta receptor was positive in pathological and normal tissue fibroblasts. Tunica albuginea from PD and VOD show similar ultrastructural and immunohistochemical alterations, whereas the corpus cavemosum shows no visible modifications.

Collagen↗