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G Anastasi

Publications and source records attributed to G Anastasi.

At least 19 recordsLinked to original sources
PubMed2005

Non-invasive assessment of motor unit anatomy in jaw-elevator muscles.

The estimation of fibre length in jaw-elevator muscles is important for modelling studies and clinical applications. The objective of this study was to identify, from multi-channel surface EMG recordings, the main innervation zone(s) of the superficial masseter and anterior temporalis muscles, and to estimate the fibre length of these muscles. Surface EMG signals were collected from 13 subjects with a 16-electrode linear array. The innervation zones of the masseter and anterior temporalis were identified and their variability intra- and inter-subject outlined. More than one main innervation zone location was identified in the masseter of all subjects and in the temporalis anterior of 12 subjects. Average estimated fibre lengths, for the right (left) side, were (mean+/-SD) 27.3+/-2.4 mm (27.0+/-1.7 mm) and 25.9+/-2.3 mm (26.6+/-1.6 mm), for the superficial masseter and temporalis anterior muscle, respectively. The range of innervation zone locations was up to approximately 50% of the fibre length, both within and between subjects. Fibre length estimates well matched with published data on cadavers. It was concluded that multi-channel surface EMG provides important and reliable information on the anatomy of single motor units in jaw-elevator muscles.

Adult↗
PubMed2005

Pre-surgical finasteride therapy in patients treated endoscopically for benign prostatic hyperplasia.

INTRODUCTION: Transurethral resection of the prostate is considered the standard technique for patients with moderate or severe lower urinary tract symptoms related to benign prostatic hyperplasia (BPH). Pathologically BPH is characterized by an increased proliferation of stromal and acinar cells, sustained by increased vascularization (neoangiogenesis). Recent studies have also shown that finasteride reduces angiogenesis and prostatic bleeding associated with BPH. Reducing the volume as a final step in reducing neoangiogenesis could thus represent a fundamental advance in limiting intra- and postoperative bleeding in patients undergoing transurethral resection of the prostate (TURP). MATERIALS AND METHODS: Our study included 60 patients undergoing TURP between January 2001 and January 2002. Of the patients, 30 received pretreatment with finasteride while 30 did not undergo any pretreatment (control group). In all the patients we evaluated the degree of peri-surgical bleeding, intended as a reduction in hemoglobin values in the 24 h following surgery. RESULTS AND CONCLUSIONS: In the group of patients pretreated with finasteride, blood loss, evaluated as a reduction in hemoglobin values, was minimal, and none of the patients required blood transfusion. The average hemoglobin loss in the 24 h following surgery was 0.9%. In the control group (average age 67 years), 4 patients (12%) required blood transfusion. The loss of hemoglobin was 2.36%. Finasteride, therefore, seems to play a fundamental role in the pretreatment of TURP patients, since by reducing dihydrotestosterone synthesis, it interacts with endothelial growth factors, thus reducing angiogenesis and preventing bleeding.

Aged↗
PubMed2004

Lithiasic obstructive uropathy. Hydronephrosis characterization by magnetic resonance pyelography.

OBJECTIVES: The purpose of this study was to evaluate the role of magnetic resonance (MR) pyelography in patients affected by hydronephrosis due to ureteric stones, in order to identify a pyonephrotic condition. MATERIALS AND METHODS: In the last 3 years, 315 patients, who had originally been investigated by ultrasonography, were evaluated with MR pyelography in order to define the etiology of obstruction. In 67 patients hydronephrosis was referred as caused by lithiasis. RESULTS: MR pyelography not only confirmed urinary tract dilatation in all patients, but also identified grade and site of obstruction, both in acute dilatation (25 patients) and in chronic obstructions (42 patients). In 7 patients, MR pyelography documented pyonephrosis that was obviously confirmed by nephrostomic drainage. CONCLUSION: MR pyelography, made with ultrafast breath-hold sequences, has a great value in identifying hydronephrosis in patients with ureteric stones. Furthermore, it provides the chance to identify pyonephrosis requiring an immediate drainage of the kidney before major complications develop.

Adult↗
PubMed2003

Validation of a high-performance liquid chromatography method for the determination of oxytetracycline, tetracycline, chlortetracycline and doxycycline in bovine milk and muscle.

High-performance liquid chromatography with diode-array detection (HPLC-DAD) was optimised and validated for the determination of tetracyclines in bovine milk and tissues. Milk and tissue samples were extracted and purified using a solid-phase extraction HLB Oasis cartridge and analysed using HPLC-DAD set at 365 nm. The analyses were carried out using the mobile phase of 0.01 M oxalic acid-acetonitrile-methanol (60:25:15, v/v/v) on a C8 column (250 x 4.6 mm I.D., 5 microm). Recoveries of tetracyclines from spiked samples at the three concentrations (0.5, 1 and 1.5) of the maximum residues limits (corresponding to 100 microg/kg for milk and the muscle) were higher than 81.1% in milk and 83.2% in muscle. The method was successfully validated for bovine milk and muscle in compliance with requirements set by draft SANCO/ 1805/ 2000 European Decision. The decision limit (CCalpha) was in the range 113.2-127.2 microg/kg and 107.7-129.9 micro/kg for all compounds in milk and muscle, respectively. The detection capability (CCbeta) was in the range 117.2-131.3 microg/kg and 114.9-133.1 microg/kg for all compounds in milk and muscle, respectively.

Animals↗
PubMed2003

Sarcoglycans in human skeletal muscle and human cardiac muscle: a confocal laser scanning microscope study.

Sarcoglycans are a subcomplex of transmembrane proteins which are part of the dystrophin-glycoprotein complex. They are expressed in the skeletal, cardiac and smooth muscle. Although numerous studies have been conducted on the sarcoglycan subcomplex in skeletal and cardiac muscle, the manner of the distribution and localization of these proteins along the nonjunctional sarcolemma is not clear. We therefore carried out an indirect immunofluorescence study on surgical biopsies of normal human skeletal muscle and of healthy human atrial myocardium biopsies of patients affected by valvulopathy. Our results indicate that, in skeletal muscle, sarcoglycans have a costameric distribution and all colocalize with each other. Only in a few cases did the alpha-sarcoglycan not colocalize with other sarcoglycans. In addition, these glycoproteins can be localized in different fibers either in the regions of the sarcolemma over band I or band A. In cardiac muscle, our results show a costameric distribution of all proteins examined and, unlike in skeletal muscle, they show a constant colocalization of all sarcoglycans with each other, along with a consistent localization of these proteins in the region of the sarcolemma over band I. In our opinion, this situation seems to confirm the hypothesis of a correlation between the region of the sarcolemma occupied by costameric proteins and the metabolic type, fast or slow, of the muscular fibers. These data, besides opening a new line of research in understanding interactions between the sarcoglycans and other transmembrane proteins, could also be extended to skeletal and cardiac muscles affected by neuromuscular and cardiovascular pathologies to understand possible structural alterations.

Biopsy↗
PubMed2003

Distribution and localization of vinculin-talin-integrin system and dystrophin-glycoprotein complex in human skeletal muscle. Immunohistochemical study using confocal laser scanning microscopy.

The vinculin-talin-integrin system and the dystrophin-glycoprotein complex (DGC) are two protein systems with structural and signaling functions, allowing interaction between muscle fibers and extracellular matrix. Although numerous studies have been conducted on these systems, their localization and distribution patterns along the nonjunctional sarcolemma are not clear. On this basis, we carried out an indirect immunofluorescence study on the vastus lateralis muscle of human adults not affected by neuromuscular diseases to better define these patterns. Our results showed that all tested proteins of the two systems have a costameric distribution; all tested proteins of the two systems colocalize with each other (about 90-95% of the cases); only alpha-sarcoglycan in a few cases (about 6%) does not colocalize with other proteins; in about 9-10% of the cases, dystrophin and beta-dystroglycan colocalize partially with other proteins; all tested proteins can be localized in different fibers, both in the region of the sarcolemma over I or A bands. The colocalization between the vinculin-talin-integrin and DGC systems may imply their functional interaction involving the structural aspect, by providing a stronger adhesion between sarcolemma and extracellular matrix in well-defined regions of the muscle fiber. Besides, their colocalization may suggest the existence of a mechanism of mutual modulation of the transmitted signals. This reciprocal control may determine, in different conditions, the prevalence of one system over another with a consequent transmission of different messages to the sarcolemma-associated cytoskeleton.

Dystrophin↗
PubMed2002

Actin-associated proteins in ameloblast differentiation.

Focal contacts are systems of adherens junctions of the cell-extracellular matrix type, which allow the transfer of fundamental signals from the extracellular matrix to nuclear compartments, capable of regulating adhesion, proliferation, migration and differentiation of cells. Recently, many authors have concentrated their attention on epitheliomesenchymal interactions which guide organogenesis of dental germ, identifying numerous growth and differentiation factors and having the inner enamel epithelial cells of the enamel organ as a target. Given that the two cellular compartments in their tooth germ are separated by a basal membrane and by an extracellular matrix, which touches it, we wanted to evaluate the presence of focal contacts through the identification of talin and vinculin, proteins of the actin-associated protein complex. In this study we utilized the hemimandibles of young Wistar rats and we extracted the related odontogenic tooth organs present at their apical end. Specimens are processed with antibody against vinculin and talin. Results show that these junctional system proteins are present at the apical poles of both cellular compartments suggesting that putative epithelial-mesenchymal interactions, other than marker molecules, may use focal contacts as a system for transmission of signals.

Actins↗
PubMed2002

AQP1 in red blood cells of uremic patients during hemodialytic treatment.

Hemodialysis influences the transport of water through the erythrocytic membrane, and induces morphologic and functional modifications. Recently water channels, called aquaporins (AQP), have been identified on the membrane of red blood cells. The aim of the present study was, therefore, to evaluate any relationships between volumetric changes in erythrocytes (MCV), plasma osmolarity and membrane expression of AQP1 in 22 uremic patients during a hemodialysis session, and compare value with those in a control group of 22 healthy volunteers. Membranal AQP1 expression was evaluated using three methods: indirect immunofluorescence under confocal microscopy, immunoenzymatic method after membrane extraction, and immunoblotting. In uremic subjects, at baseline membrane AQP1 expression was significantly lower, whereas plasma osmolality was higher than in controls. At 1 and 2 h of replacement therapy, a progressive increase was observed in erythrocytic AQP1, values similar to those in controls being attained after 3.5 h. During the session osmolality values reduced progressively, becoming significantly lower than basal values. The mean erythrocytic corpuscular volume in patients with ESRD was significantly lower than in cntrols at baseline. This value increased during hemodialysis, attaining statistical significance with respect to the basal value at 3.5 h of dialysis. Close correlations were found between plasma osmolality and AQP1 values (r = -0.930; p < 0.05), and also between MCV and plasma osmolality trend (r = -0.909; p < 0.05). There was a linear correlation (r = 0.63, p < 0.05) between plasma AVP concentrations and plasma osmolality. The variations found in plasma osmolarity during hemodialysis, may induce AQP1 expression on the membrane of intact red blood cells.

Adult↗
PubMed2000

The CD85/LIR-1/ILT2 inhibitory receptor is expressed by all human T lymphocytes and down-regulates their functions.

The inhibitory molecule CD85/LIR-1/ILT2 has been detected previously on the surface of a small proportion of T lymphocytes. In this study, evidence is provided that, although only a fraction of CD3+ cells are stained by mAb specific for CD85/LIR-1/ILT2 on their surface, this inhibitory receptor is present in the cytoplasm of all T lymphocytes, and that it is detectable on the surface of all T cell clones by the M402 mAb. Biochemical analyses further demonstrate that CD85/LIR-1/ILT2 is present in all T clones analyzed, and that the protein is tyrosine-phosphorylated. Expression of mRNA coding for CD85/LIR-1/ILT2 has been assessed by RT-PCR. Notably, in the NKL cell line and in one T cell clone, amplification of the messenger required 30 cycles only, whereas, in other T cell clones, an amplification product was detected by increasing the number of cycles. CD85/LIR-1/ILT2 inhibits CD3/TCR-mediated activation in both CD4+ and CD8+ clones, and it down-regulates Ag recognition by CD8+ cells in a clonally distributed fashion. Addition of anti-ILT2 HP-F1 mAb in the cytolytic assay enhances target cell lysis mediated by Ag-specific CTL. This could be due to interference of the mAb with receptor/ligand interactions. In contrast, HP-F1 mAb cross-linking triggers inhibitory signals that reduce cytotoxicity. CD85/LIR-1/ILT2 also controls responses to recall Ags and, in low responders, its engagement sharply increases T cell proliferation. The inhibitory function of the molecule is also confirmed by its ability to reduce CD3/TCR-induced intracellular Ca2+ mobilization.

Antibodies, Monoclonal↗
PubMed2000

Ultrastructural and immunohistochemical study of basal lamina of the testis in adolescent varicocele.

OBJECTIVE: To evaluate a possible involvement of the extracellular matrix (ECM) in the testes of adolescents with varicocele. DESIGN: Cross-sectional study. SETTING: University-based medical center. PATIENT(S): Twenty-four adolescents aged between 13 and 18 years underwent surgical treatment for repair of left idiopathic varicocele. INTERVENTION: A testis biopsy was performed at time of surgery. MAIN OUTCOME MEASURE(S): Transmission electron microscopy study of basal lamina and immunofluorescence studies of collagen type IV and laminin, two major components of basal lamina. RESULT(S): Transmission electron microscopy observations showed an uneven profile of the basal lamina with a variable thickness. Immunofluorescence studies showed an irregular immunofluorescent line that appeared interrupted in some observations. Collagen type IV showed some areas of strong immunostaining with other areas with reduced immunoreactivity. CONCLUSION(S): Our ultrastructural and immunohistochemical observations highlight focal damage at the level of peritubular basal lamina, but this damage is not as severe as that described in adult varicocele. Initial involvement of basal lamina could represent one of the mechanisms responsible for varicocele-induced histologic alterations of the testes.

Adolescent↗
PubMed2000

Molecules that inhibit T-cell functions: cytochemical localization and shuttling.

Adaptive immune responses to antigens are mediated by specific receptors expressed on B cells (BCR's) and T cells (TCR's). Effector cells and memory cells are produced following a proliferative wave that accounts for clonal expansion. If not down-regulated, clonal expansion might lead to uncontrolled lymphoproliferation that would be harmful for the organism. Several mechanisms that account for the down-sizing of activated lymphocyte clones are briefly reviewed here. We next consider in detail one such mechanism that deals with the functional characterization and the immunocytochemical localization of two T-cell inhibitory molecules, namely the Cytotoxic T Lymphocyte Antigen-4 (CTLA-4) and the HP-F1 antigen, both present in all T lymphocytes. CTLA-4 and HP-F1 inhibit CD4+ T-helper cell proliferation and the lytic ability of CD8+ T-cytotoxic cells in non-specific and in antigen-specific cytolytic assays. Interestingly, a clonal distribution exists as for the ability of CTLA-4 and HP-F1 to inhibit T-cell functions. In resting and activated T cells, both molecules are largely confined in the endosomal compartment, as shown by immunofluorescence analyses. However, upon interaction of T cells with Antigen-Presenting Cells (APC's) or with target cells that must be killed, CTLA-4 molecules are transported to the plasma membrane, at the site of cell-to-cell contact where, following interaction with ligands, they trigger inhibitory signals.

Abatacept↗
PubMed2000

[Unusual case of calcified renal fibroma].

The renal fibroma is an extremely rare event that takes its origin from parenchima, from the peri-renal tissues or from the renal capsule. A case of renal fibroma of a rarely met medullary origin is described.

Adult↗
PubMed2000

[Validity of PSA density of the transition zone in the diagnosis of prostate cancer].

One hundred four patients (mean age 70.6 years) with prostatic specific antigen (PSA) values between 4 and 10 ng/ml (average 7.9 ng/ml), and with no suspects for neoplasia by digital rectal examination (DRE) and transrectal ultrasound (TRUS) were studied. In all patients PSA density for the entire prostate (PSAD) and PSA density for the transition zone (PSAT) were calculated. TRUS was performed using a 5 MHz probe. Prostate and transition zone volumes were obtained by ellipsoid formula. Aim of the study was to evaluate the PSAT predictivity for prostate cancer compared to the PSAD. Sixteen out of 104 patients (15.4%) had histologically confirmed prostate cancer, and 88 (84.6%) had benign prostatic hyperplasia. When cut-off for PSAD was 0.15 ng/ml/cc, specificity and sensitivity were respectively 75% and 68% with positive and negative predictive values of 54% and 17%; when cut-off for PSAT was 0.34% ng/ml/cc, sensitivity and specificity were respectively 100% and 68% with positive and negative predictive values of 60% and 18%. Our results, according to the literature data, suggest that PSAT seems to have a higher predictivity for prostate cancer than PSAD, providing an optimization for the employ of prostatic biopsy, especially for those patients with PSA values between 4 and 10 ng/ml.

Aged↗
PubMed2000

[Usefulness of ultrasonography in the diagnosis of acute scrotal edema].

Ultrasonography has gained an important role for the diagnosis of acute and chronic scrotal lesions. We report our experience on 6 cases of acute scrotal edema. The etiology of edema was congestive cardiopathy (two patients), glomerulonephrosis (three patients) and lumboaortic lymphnode metastases from bladder transitional cell carcinoma (one patient). Ultrasound scan scrotal appearances were similar in all examined patients, and the only pathologic findings observed were "onion" like appearance and a thickened scrotal wall. Therefore, to define acute scrotal edema etiology, it isn't enough an ultrasound examination, but it's necessary to extend the ultrasound scan assessment to other organs.

Acute Disease↗
PubMed1998

Comparative responses to three different types of interferon-alpha in patients with chronic hepatitis C.

We investigated the efficacy and tolerability of three different types of interferon-alpha, administered with the same schedule to naive patients with chronic hepatitis C. One hundred and seven patients with histologically proven chronic hepatitis C were enrolled during a period of three years and randomly divided into three groups, to receive (a) leukocyte-interferon-alpha, 6 MU three times a week for 4 months, followed by 3 MU three times a week for 8 months (Group I); (b) recombinant-IFN-alpha-2a, with the same schedule (Group II); and (c) lymphoblastoid-IFN-alpha-N1, with the same schedule (Group III). All patients were followed-up for 6 months to evaluate the long-term response. The 'Complete Response' rates at the end of treatment were: 50%, 46.1% and 41.6%, in Groups I, II and III, respectively; most patients relapsed after the end of therapy, so that the 'sustained responders' were, after 6 months of follow-up, 18.7%, 23.1% and 19.4%, respectively. Analysis of pre-treatment variables showed that age, ALT and gamma GT serum levels, as well as the prevalence of liver cirrhosis, were lower in the 'sustained responder' group. Four patients were eliminated from the study because of severe adverse events: 1, 2 and 1, in Groups I, II and III, respectively. Our results indicate a similar response rate with the three different types of interferon-alpha, although at baseline, age, serum levels of gamma globulins and the number of patients with cirrhosis-possible negative-risk factors, were higher in Group I.

Aged↗
PubMed1996

[Procollagen III and laminin in chronic viral hepatopathies].

OBJECTIVES: We measured serum concentrations of the N-terminal peptide of type III procollagen (PIIIP) and laminin (Lam-P1) in patients with chronic viral liver disease in the various stages of the clinical course, to judge their value in assessing liver fibrogenesis, and also compared them with a number of liver function tests and histological scores of inflammation and fibrosis. METHODS: Twenty-nine patients with chronic persistent hepatitis, 39 with chronic active hepatitis and 42 with liver cirrhosis were studied. The control group was composed of 45 healthy blood donors. Serum PIIIP and Lamp-P1 were determined by radioimmunoassay; hepatic function was measured by routine assay; liver fibrosis and inflammation were graded on a 0-3 score scale. RESULTS: A significantly higher increase in serum levels of PIIIP and Lam-P1 was found in the liver cirrhosis group compared with the other groups (p < 0.05). Serum PIIIP correlated with transaminase levels in the chronic active hepatitis group and with gammaglobulin and total bilirubin in the liver cirrhosis group. A positive correlation was found only with gammaglobulin and total bilirubin in the cirrhosis group. A positive correlation was found between serum PIIIP levels and the rating scale of liver necrosis. In contrast, for Lam-P1 values, a correlation with the rating scale of necrosis and fibrosis was found. CONCLUSION: Our findings confirmed the increase of PIIIP and Lamp-P1 in chronic viral liver disease, but because of the frequent overlap values, they cannot be used as substitutes for liver biopsy for diagnosis. The correlations with the histological findings indicate that these two markers can be used during the follow-up of patients receiving anti-inflammatory or anti-fibrotic treatment.

Adult↗
PubMed1996

Immunolocalization of the costameres in human skeletal muscle fibers: confocal scanning laser microscope investigations.

BACKGROUND: The costameres in skeletal muscle fibers were first described by Pardo et al. (1983a) and have been defined as transverse circumferential elements of the cytoskeleton associated to the sarcolemma. Specific immunostaining for vinculin shows that the costameres overlie I bands. However, an exact correlation between the costameres and the Z line is uncertain, although approximately 10 proteins so far have been localized in the costameres. To define the exact localization of costameres in human skeletal muscle fibers, we carried out an immunofluorescence study using confocal scanning laser microscopy on the fascia lata muscle of adult males. METHODS: Samples were fixed in 3% paraformaldehyde; frozen sections were treated with antivinculin, antitalin, antidesmin, and anti-alpha-actinin, then immunostained with TRITC. For double localization, the TRITC-streptavidin, as a marker for vinculin and FITC-streptavidin a marker for desmin, were used. RESULTS: The distance between two subsequent transverse lines of actininf indicated that muscle fibers were well stretched. Processing, with different software functions of the images obtained using CLSM, shows that vinculin and talin are only present in the sarcolemmal lattice. Immunostaining for vinculin and double immunostaining for vinculin and desmin demonstrate that costameres superimpose underlying I bands without interruption at the Z line. Immunostaining for talin showed that the protein is located in correspondence with the I band and M line. CONCLUSIONS: We believe that costameres are "proteic machinery." The findings of the present study suggest that it is possible to determine the width and the period of each proteic component. In addition, we indicate that costameres are present in correspondence with M line.

Actinin↗