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C Greco

Publications and source records attributed to C Greco.

At least 19 recordsLinked to original sources
PubMed2004

C-MYB, serum P-53M, genetic instability, labeling index and endoscopic findings in patients with adenoma or colorectal cancer.

Structural alterations of c-myb proto-oncogenes and serum p53 mutant level, Mitomycin C-induced chromosomal aberrations and sister chromatid exchanges and proliferative activity of mucosa (H3-thymidine -labeling index LI) are often determined to obtain more information about the diagnosis and prognosis of neoplastic and preneoplastic lesions of the colon. The aim of this study was to evaluate the endoscopic findings of a 5 year follow-up in three groups of subjects (normal, adenoma or cancer patients) and to correlate these findings with the biological alterations in the same subjects between 1990 and 1993. We analyzed 200 subjects (118 Male and 82 Female), 78 normal subjects (group A), 60 patients with adenoma (group B) and 62 with carcinoma (group C). Data regarding endoscopic lesions was collected from June 1998 to December 2000 after a 5 year follow-up and correlated with the biological alterations in the same subjects between 1990--1993. We obtained endoscopic findings from 23/137 subjects (16.8%), 6/137 (4.4%) died from other causes and 108/137 (78.8 %) were negative for lesions. The percentage of disease after 5 years is not statistically different among the three groups (groups A, B and C). There was no statistically significant association between values of the labeling index, structural alterations of c-myb, p-53-M serum levels and chromosomal aberrations and endoscopic findings in the 5 year follow-up. We conclude that the biological markers considered are not able to stratify patients in terms of risk of progression to malignant disease.

Adenoma↗
PubMed2003

Potential usefulness of serum p53 for laboratory management of plasma cell dyscrasias.

We measured the serum levels of p53 mutant protein (p53M-ELISA) in 65 patients with plasma cell dyscrasia (PCD) and compared them with some conventional laboratory variables. Our aim was to assess, for the first time, the potential of this parameter as a new marker for laboratory management of PCD. Twenthy-tree out of 65 patients had monoclonal gammapathy of undetermined significance (MGUS) and 42 suffered from multiple myeloma (MM). MM patients, with no prior chemotherapy consecutively entered this study. They were treated with standard regimens of Melphalan and Prednisone (MP) and were analyzed for serum p53M level from the time of diagnosis to response to therapy or death. A subgroup of nine patients was regularly monitored for changes occurring in p53M levels during MP therapy. Serum levels of p53M were elevated in MM patients compared with MGUS and healthy controls (p = 0.002). Significantly higher p53M levels were shown by MM patients refractory to chemotherapy than by responding patients (0.38 ng/ml vs 0.22 ng/ml, p = 0.05). The measurement of serum p53M in the nine patients during the course of chemotherapy correlated with disease progression or response to therapy. If confirmed on a larger series of patients, these results suggest a potential role of serum p53 mutant levels in laboratory management of PCD patients.

Aged↗
PubMed2001

Angioplasty increases coronary sinus F2-isoprostane formation: evidence for in vivo oxidative stress during PTCA.

OBJECTIVES: Isoprostanes, stable end-products of oxygen free radical mediated-lipid peroxidation, were measured in the coronary vessels during percutaneous transluminal coronary angioplasty (PTCA) to provide direct evidence for enhanced oxidative stress in a local milieu in vivo. BACKGROUND: Percutaneous transluminal coronary angioplasty is associated with complications such as myocardial stunning and accelerated restenosis, which at least in part are mediated by oxygen free radicals. Because isoprostanes are markers of oxidant stress and potent vasoactive compounds, the formation of which is not inhibited by aspirin treatment in vivo, it is possible that these mediators are increased locally during PTCA. METHODS: In 12 coronary artery disease patients who were given aspirin and ticlopidine, blood samples from coronary sinus were taken immediately before and immediately upon balloon deflation during PTCA. Isoprostane F2alpha-III, isoprostane F2alpha-VI, and TxB2 were quantified after extraction and chromatography using a stable dilution isotope gas chromatography/mass spectrometry assay. RESULTS: Coronary sinus and left main coronary artery levels of iPF2alpha-III and iPF2alpha-VI at baseline were (mean +/- SEM) 40 +/- 9 pg/ml and 115 +/- 10 pg/ml, respectively. The TxB2 levels were undetectable. Following PTCA, isoprostane levels markedly increased (mean +/- SEM): iPF2alpha-III, 125 +/- 12 pg/ml (p < 0.001); iPF2alpha-VI, 295 +/- 20 pg/ml (p < 0.001), whereas TxB2 levels remained undetectable. CONCLUSIONS: These results indicate that PTCA induces coronary sinus increase in F2-isoprostane formation, and they also provide direct evidence for enhanced oxidative stress in a local milieu in vivo. Thus, an increased F2-isoprostane formation could play a role in the pathogenesis of some PTCA-associated untoward events.

Aged↗
PubMed2001

Usefulness of histological examination for the diagnosis of onychomycosis.

BACKGROUND: [corrected] Direct microscopy and culture tests currently used in the diagnosis of nail mycosis can yield false-negative results, and confirmation of the pathogenic agent, especially in non-dermatophyte infections, is often a lengthy process. OBJECTIVE: The aim of this study was to investigate the usefulness of the histological examination of nail clipping samples in supplementing the standard microscopic and culture techniques for the diagnosis of onychomycosis. PATIENTS AND METHODS: One hundred and seventy-two subjects affected by nail alterations suggestive of onychomycosis were evaluated. Nail specimens were studied with 3 different techniques: direct microscopic examination of a 40% KOH clarified preparation, fungal culture and histological examination. Patients positive for fungal infection were re-evaluated with the same techniques after treatment with oral terbinafine, fluconazole or itraconazole and topical application of bifonazole or ciclopirox for 2 months. RESULTS: Direct microscopy was positive in 102 (59.3%) nail specimens. The culture test was positive in 90 cases (52.9%), showing a dermatophyte in 45, a yeast in 23 and a mould in 22 samples. The histological examination was positive in 94 (54.6%) samples. In 4 cases, it was the only investigation confirming the clinical diagnosis of nail mycosis. In most of the cases, the morphological aspect of the hyphae and/or spores suggested also to which group of pathogens (dermatophytes, yeasts or moulds) the mycetes observed in the histological sections could be ascribed. The concurrent presence of a dermatophyte and a mould was evidenced in a few specimens. The control histological examination at the end of the treatment showed negative results or residual non-vital hyphae and/or spores. CONCLUSIONS: Results of the present study indicate that the histological examination of nail clipping specimens is a relatively inexpensive, rapid and easily performed procedure. It is useful to confirm or refute the results of routine microscopy and culture tests. Moreover, nail histopathological observation may help in ascribing a pathogenic role of non-dermatophyte isolates and evaluating the effectiveness of antifungal treatment.

Adolescent↗
PubMed2000

Incidence of chromosomes 1 and 17 aneusomy in breast cancer and adjacent tissue: an interphase cytogenetic study.

BACKGROUND: Characterization of the biopathologic events underlying the early steps of breast carcinogenesis may have a dramatic impact on reducing breast cancer mortality. Genes involved in breast tumorigenesis are localized on chromosomes 1 and 17, and numeric aberrations of these chromosomes have been correlated with breast cancer tumorigenesis and progression. According to the field cancerization hypothesis, specific chromosome aberrations may be present in breast cancer and in normal-appearing adjacent tissue. The latter changes reflect the genomic damage that follows longterm carcinogenic exposure and precede the morphologically detectable neoplastic transformation. We hypothesize that detection of these aberrations in benign breast epithelium may provide a tool for molecular risk assessment. STUDY DESIGN: Using fluorescence in situ hybridization with centromere-specific probes, we determined the status of chromosomes 1 and 17 in fresh imprints of 28 samples of primary tumors and 54 samples of their surrounding uninvolved parenchyma taken from patients undergoing operations for breast carcinoma. Ten contralateral breast biopsy specimens collected from patients with previous breast carcinoma were also evaluated as a surrogate of a high-risk group to rule out the hypothesis that chromosomal aneusomy in tumor-adjacent tissue could be related to a paracrine effect of the primary tumor. Ten samples of benign breast tissue taken from patients at low risk were used as controls to define tolerance limits for aneusomy definition. RESULTS: Using threshold values of 40% of signal loss and 13% of signal gain to define chromosome aneusomy (ie, mean + 3 SDs of the control group signals), we found the following: 1) almost all primary breast tumors were aneusomic for chromosomes 1 and 17; 2) primary breast tumor and adjacent uninvolved parenchyma shared the same pattern of chromosomes 1 and 17 aneusomy in 66.7% of patients; and 3) chromosomes 1 and 17 aneusomies in contralateral benign breast samples from high-risk patients were not different from those in primary breast tumor or adjacent tissue samples. CONCLUSIONS: These results suggest that chromosomes 1 and 17 aneusomy may represent an intermediate biomarker of breast tumorigenesis potentially useful to detect patients at high risk of breast carcinoma who may benefit from preventive interventions.

Adult↗
PubMed2000

Usefulness of transesophageal echocardiography during open heart surgery of mitral stenosis.

BACKGROUND: The aim of this study was to verify if the use of intraoperative transesophageal echocardiography (TEE), by detecting mitral insufficiency or residual stenosis during surgery, may improve medium term results in patients with severe mitral stenosis who undergo open heart valvuloplasty. METHODS: This prospective study included twenty-two patients (20 women and 2 men) with a mean age of 49+/-13 years with severe mitral stenosis. Mean follow-up was 32 months (range 12-55 months). All the patients underwent transthoracic echocardiography (TrE) before surgery and intraoperative TEE. Before surgery the mean transmitral gradient was 11+/-6.8 mmHg, the mean pressure half time (PHT) area was 0.89+/-0.19 cm2, the mean echo score was 8.9+/-2.2. Intraoperative TEE before the repair showed a mean echo score of 7.9+/-1.8. RESULTS: Two patients with unsatisfactory repair at TEE underwent immediate valve replacement. In the remaining patients, mean transmitral gradient and PHT valve area before discharge was 5.2+/-3 mmHg and 2.5 cm2. No patients had more than trivial mitral regurgitation. During the follow-up two patients had to be reoperated. Patients with poor immediate (2 patients) or medium term results (2 patients), had a mean echocardiographic score of 12.24, while patients with a satisfactory medium term outcome had a mean score of 7.27 (p<0.001). CONCLUSIONS: Intraoperative TEE may guide the surgeon in the assessment of valvuloplasty. However the absence of mitral regurgitation after repair and at discharge cannot predict the medium term results, which are related to the degree of the disease of the mitral valve.

Adult↗
PubMed1999

Site-specific migration and neuronal differentiation of human neural progenitor cells after transplantation in the adult rat brain.

Neural progenitor cells obtained from the embryonic human forebrain were expanded up to 10(7)-fold in culture in the presence of epidermal growth factor, basic fibroblast growth factor, and leukemia inhibitory growth factor. When transplanted into neurogenic regions in the adult rat brain, the subventricular zone, and hippocampus, the in vitro propagated cells migrated specifically along the routes normally taken by the endogenous neuronal precursors: along the rostral migratory stream to the olfactory bulb and within the subgranular zone in the dentate gyrus, and exhibited site-specific neuronal differentiation in the granular and periglomerular layers of the bulb and in the dentate granular cell layer. The cells exhibited substantial migration also within the non-neurogenic region, the striatum, in a seemingly nondirected manner up to approximately 1-1.5 mm from the graft core, and showed differentiation into both neuronal and glial phenotypes. Only cells with glial-like features migrated over longer distances within the mature striatum, whereas the cells expressing neuronal phenotypes remained close to the implantation site. The ability of the human neural progenitors to respond in vivo to guidance cues and signals that can direct their differentiation along multiple phenotypic pathways suggests that they can provide a powerful and virtually unlimited source of cells for experimental and clinical transplantation.

Animals↗
PubMed1999

Calpain III mutation analysis of a heterogeneous limb-girdle muscular dystrophy population.

OBJECTIVE: To determine the frequency of calpain III mutations in a heterogeneous limb-girdle muscular dystrophy (LGMD) population. BACKGROUND: Mutations of the calpain III gene have been shown to cause a subset of autosomal recessive LGMDs. Patient populations studied to date have been primarily of French and Spanish origin, in which calpain III may cause 30% of autosomal recessive MDs. The incidence of calpain III mutations in non-French/Spanish MD patients has not been studied thoroughly. No sensitive and specific biopsy screening methods for detecting patients with abnormal calpain III protein are available. Thus, detection of patients relies on direct detection of gene mutations. METHODS: The authors studied the calpain III gene in 107 MD patient muscle biopsies exhibiting normal dystrophin. Muscle biopsy RNA was produced for each patient, and the entire calpain III complementary DNA was screened for mutations by reverse-transcriptase PCR/single-strand conformation polymorphism using three different conditions. RESULTS: The authors identified nine patients (eight unrelated) with causative mutations. Six of the seven distinct mutations identified are novel mutations and have not been described previously. CONCLUSION: The results suggest that approximately 9.2% of patients in the heterogeneous population with an LGMD diagnosis will show mutations of the calpain III gene. Interestingly, two patients were heterozygous for a single mutation at the DNA level, whereas only the mutant allele was observed at the RNA level. This suggests that there are undetectable, nondeletion mutations that ablate expression of the calpain III gene.

Adolescent↗
PubMed1999

Immunoscintigraphy of atherosclerotic uncomplicated lesions in vivo with a monoclonal antibody against D-dimers of insoluble fibrin.

To test the effectiveness of a new F(ab')2 monoclonal antibody against human fragment D-dimer of cross-linked fibrin in the detection of uncomplicated atherosclerotic lesions of the carotid vessel previously documented at echo-color-Doppler and selective arteriographic study, 8 patients underwent a scintigraphic study including dynamic and early and delayed (3 h later) static imaging of the neck after injection of a bolus of 99mTc-labeled monoclonal antibody, and were subsequently operated. Vessel specimens and blood samples were drawn at operation and counted. No adverse reaction occurred after administration of the monoclonal antibody. The atherosclerotic lesion appeared as a focal area of asymmetrical tracer uptake, already visible at early images in four patients, and at delayed images in five. The average tracer uptake ratio between pathological and normal vessels was 1.40+0.24 (P < 0.05) at time-activity curves derived from dynamic images, 2.17+/-0.97 (P < 0.05) at early static images and 2.05+/-0.98 (P < 0.05) at delayed static images, respectively. Mean vessel to blood uptake rate of specimens obtained at operation was 2.22+/-0.59 (P < 0.001). The study shows that the 99mTc-labeled antibody was found to be safe and capable of detecting atherosclerotic plaques in humans.

Aged↗
PubMed1999

Phenotypic and genotypic alterations characterize patients bearing plasma cell dyscrasias with a high M-component.

As at present only a long-term follow-up can fully determine whether monoclonal gammapathies of undetermined significance (MGUS) will evolve into multiple myeloma (MM), this study attempted to identify other variables connected with the amount of monoclonal component (MC), generally considered as the most reliable marker of malignant evolution. Thirty-four MGUS subjects showing a high MC (> or = 15.0 g/l) but without clinical evidence of MM (MGUS group b), were characterized for their phenotypic and genotypic profile by comparing them either with 40 MM patients or with 24 subjects affected by a benign form of monoclonal gammapathy (MGUS group a) according to the standard criteria. In addition to the usual laboratory markers, the levels of expression of a panel of CD membrane subsets were measured on B and T lymphocytes. Also, the serum level of the p53 mutant protein and the structural alterations of the c-myc oncogene were evaluated. The results show that for MGUS group b patients, an increased M-protein was accompanied by significantly increased levels of peripheral blood CD3+ T cells and oncogenetic aberrations in c-myc. Since a high serum MC level seems to indicate a greater likelihood of malignant transformation for MGUS patients, these findings suggest that this relationship may be a result of the concomitant alterations observed at a phenotypic and genotypic level. Such alterations may be potentially useful as surrogate markers for the transition of benign to malignant (MM) plasma cell dyscrasia.

Adult↗
PubMed1998

Preoperative identification of viable myocardium: effectiveness of nitroglycerine-induced changes in myocardial Sestamibi uptake.

In order to predict tissue viability in infarcted myocardial areas, changes induced by nitroglycerine infusion on Sestamibi myocardial uptake were evaluated in 37 patients with previously confirmed myocardial infarction undergoing coronary artery bypass grafting, and compared with echocardiographic and perfusional changes occurring after the operation. The improvement of Sestamibi uptake after nitroglycerine correctly classified 24/26 (92%) patients showing postoperative improvement of wall motion in the infarcted area, whereas 24/31 (77%) patients with nitroglycerine-induced increase in Sestamibi uptake had improved wall motion after operation. The presence of collateral flow to the infarcted area was associated with a significantly (P < 0.01) higher increase in Sestamibi uptake both during nitroglycerine infusion and postoperatively. An increase in wall motion score after operation was associated with a significantly higher (P < 0.05) increase in Sestamibi uptake score during nitroglycerine infusion. Thus, the results of this study suggest that Sestamibi perfusional myocardial scintigraphy during nitroglycerine infusion is capable of assessing viable but chronically hypoperfused myocardium and predicting postoperative wall motion and perfusional improvement, to yield the best results in patients with evidence of collateral circulation that supplies the infarcted area.

Aged↗
PubMed1997

Generation and transplantation of EGF-responsive neural stem cells derived from GFAP-hNGF transgenic mice.

EGF-responsive neural stem cells isolated from murine striatum have the capacity to differentiate into both neurons and glia in vitro. Genetic modification of these cells is hindered by a number of problems such as gene stability and transfection efficiency. To circumvent these problems we generated transgenic mice in which the human GFAP promoter directs the expression of human NGF. Neural stem cells isolated from the forebrain of these transgenic animals proliferate and form clusters, which appear identical to stem cells generated from control animals. Upon differentiation in vitro, the transgenic stem cell-derived astrocytes express and secrete bioactive hNGF. Undifferentiated GFAP-hNGF or control stem cells were transplanted into the striatum of adult rats. One and 3 weeks after transplantation, hNGF was detected immunocytochemically in an halo around the transplant sites. In GFAP-hNGF-grafted animals, intrinsic striatal neurons proximal to the graft appear to have taken up hNGF secreted by the grafted cells. Ipsilateral to implants of GFAP-hNGF-secreting cells, choline acetyltransferase-immunoreactive neurons within the striatum were hypertrophied relative to the contralateral side or control-grafted animals. Further, GFAP-hNGF-grafted rats displayed a robust sprouting of p75 neurotrophin receptor-positive fibers emanating from the underlying basal forebrain. These studies indicate that EGF-responsive stem cells which secrete hNGF under the direction of the GFAP promoter display in vitro and in vivo properties similar to that seen following other methods of NGF delivery and this source of cells may provide an excellent avenue for delivery of neurotrophins such as NGF to the central nervous system.

Animals↗
PubMed1997

[Assessment of the accuracy of position in breast irradiation with isocentric technique using an electronic system to acquire portal images].

This study investigated the accuracy of daily patient positioning in an isocentric set-up for breast irradiation. This was achieved through the assessment of both systematic and random errors measured as discrepancies between reference simulation images and portal images obtained with an on-line electronic portal imaging device (EPID). To this end, 10 portal images for each of the tangential fields were obtained in 12 consecutive patients and the images were compared to reference simulation films with dedicated software tools provided with the EPID. The discrepancies measured for each set of images were analyzed statistically. Most variations in each series both in terms of cranio-caudal and of lateral displacement appeared to be random, with mean standard deviations of 2.3 and 2.8 mm, respectively. Such variations between reference fields and portal images tend to counteract one another and do not usually play a significant role in the overall accuracy of patient set-up. In some cases, however, the distribution of the variations occurred in a well-defined pattern indicating a systematic error in patient positioning. This study shows that our set-up technique for breast irradiation is relatively accurate and reproducible, and most of the observed errors were below the 5 mm cut-off level, but it stresses the need of accurate quality assurance programs in radiotherapy. Electronic portal imaging devices are excellent tools for fast portal image acquisition, and permit the accurate assessment of discrepancies with respect to reference images.

Breast Neoplasms↗
PubMed1997

[Three-dimensional transesophageal echocardiography: a new cardiologic diagnostic tool. Initial experience with 150 patients].

BACKGROUND: Three-dimensional transesophageal echocardiography is a new diagnostic tool and its potential has been investigated mainly in international centers dealing with research in the field of cardiac pathologies. The clinical usefulness and the potential additional information over multiplane transesophageal echocardiography in daily clinical practice have not been exstensively studied. OBJECTIVES: This study sought to assess the feasibility and to define the potential role of three-dimensional technique in a clinical cardiology department. POPULATION AND METHODS: One hundred-fifty patients (73 males, 77 females) aged 17-82 underwent a three-dimensional transesophageal echocardiographic study. Indications for the study were the following: 39 mitral (26%), 13 aortic (8%) and 4 tricuspidal (2%) valvulopathies, 23 valvular prostheses (15%), 6 aortic diseases (4%), 16 sources of embolism (10%), 16 congenital heart diseases (10%), 14 ischemic heart diseases (9.3%), 14 cardiomyopathies (9%), 5 other pathologies (3%). The 3 D examination quality was graded as insufficient, sufficient and good. The information obtained by "volume rendered" and "anyplane" three-dimensional echocardiography were compared with the traditional two-dimensional images to determine whether they provided additional information. RESULTS: A total of 288 acquisitions were obtained in the 150 patients (1.9 acquisitions per patient). Examinations were graded of good quality in 99 patients (61%), sufficient in 36 (24%) and insufficient in 15 patients (10%). Additional informations were obtained in 33 patients (22%) by "volume rendered" echocardiography and by "anyplane echocardiography", including mitral regurgitation or repair for valvular prolapse (11 patients), aortic valve malformations and endocarditis (4 patients), congenital heart diseases (9 patients), right ventricular dysplasia (6 patients) or hypertrophic cardiomyopathy (1 patient), tricuspid regurgitation (2 patients). The additional information were obtained in patients in the group of good 3 D reconstructions quality in all but two cases. CONCLUSIONS: The diagnostic use of the transesophageal technique with 3 D facilities permitted to obtain an overall 22% of additional information. These results will stimulate further study to evaluate the advantages of the three-dimensional technique in specific clinical fields of application.

Adolescent↗