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M Marini

Publications and source records attributed to M Marini.

At least 37 records · Page 2Linked to original sources
PubMed2003

Large-scale spatial distribution of virioplankton in the Adriatic Sea: testing the trophic state control hypothesis.

Little is known concerning environmental factors that may control the distribution of virioplankton on large spatial scales. In previous studies workers reported high viral levels in eutrophic systems and suggested that the trophic state is a possible driving force controlling the spatial distribution of viruses. In order to test this hypothesis, we determined the distribution of viral abundance and bacterial abundance and the virus-to-bacterium ratio in a wide area covering the entire Adriatic basin (Mediterranean Sea). To gather additional information on factors controlling viral distribution on a large scale, functional microbial parameters (exoenzymatic activities, bacterial production and turnover) were related to trophic gradients. At large spatial scales, viral distribution was independent of autotrophic biomass and all other environmental parameters. We concluded that in contrast to what was previously hypothesized, changing trophic conditions do not directly affect virioplankton distribution. Since virus distribution was coupled with bacterial turnover times, our results suggest that viral abundance depends on bacterial activity and on host cell abundance.

Bacteria↗
PubMed2003

Abnormal vascular network complexity: a new phenotypic marker in hereditary non-polyposis colorectal cancer syndrome.

BACKGROUND: Hereditary non-polyposis colorectal cancer (HNPCC) (Lynch cancer family syndrome I (LCFS1) and II (LCFS2)) is one of the most common hereditary cancer disorders. HNPCC results from dominantly inherited germline mutations in mismatch repair (MMR) genes, leading to genomic instability and cancer. No predictive physical signs of HNPCC are available to date. AIMS: Increased complexity in tumour associated vascular growth has been reported. Here, we tested the hypothesis that an increased vascular network complexity is a phenotypic marker for LCFS2. METHODS: Fourteen subjects from an LCFS2 kindred (gene carriers, n=5; non-carriers, n=9) and 30 controls were examined. Fractal dimension (D) at two scales (D (1-46), and D (1-15), tortuosity (minimum path dimension, Dmin), and relative Lempel-Ziev complexity (L-Z) of the vascular networks from the lower gingival and vestibular oral mucosa were measured. RESULTS: LCFS2 networks exhibited a significantly increased overall complexity at both larger (D (1-46): 1.82 (0.04) v 1.68 (0.08); p<0.0001) and smaller (D (1-15): 1.51 (0.11) v 1.20 (0.09); p<0.0001) scales, increased destructured randomness (L-Z: 0.77 (0.09) v 0.56 (0.03); p<0.0001), and decreased vessel tortuosity (DMIN: 1.02 (0.03) v 1.07 (0.04); p=0.0005) compared with control patterns. The vascular networks of LCFS2 gene carriers showed higher complexity at the smaller scale (D (1-15): 1.59 (0.12) v 1.47 (0.07); p=0.034), and higher destructured randomness (L-Z: 0.85 (0.11) v 0.73 (0.05); p=0.013) than those of non-carriers. CONCLUSIONS: Increased oral vascular network complexity is a previously unrecognised phenotypic marker for LCFS2, and is related to gene mutation carrier status.

Adult↗
PubMed2003

Lectin binding in the human umbilical cord from normally grown pregnancies and from pregnancies complicated by intra-uterine growth retardation with absent or reversed diastolic flow.

The content and the distribution of the glycoconjugate sugar residues were investigated in the human umbilical cord from normally grown pregnancies and from pregnancies complicated by intra-uterine growth retardation with absent or reversed flow in the umbilical artery. The gestational age range was 29-41 weeks. For this purpose, a battery of eight horseradish peroxidase conjugated lectins was used (ConA, WGA, PNA, SBA, DBA, LTA, UEA I, and OOA; see text). Our data showed that in both study groups ConA, WGA and PNA (after neuraminidase digestion) and LTA, UEA I, and OOA reacted with Wharton's jelly and vessels of the umbilical cord from the first weeks of gestation considered. SBA reactivity was observed only in the amniotic epithelial cells of the jelly and in the endothelial cells of the vessels. The reactivity with the most part of the lectins decreased or was lacking in the various components of the umbilical cord between 39 and 41 weeks of gestation in the normal group and between 36 and 37 weeks of gestation in the pathological one. Moreover, the intensity of reactivity with ConA, WGA and PNA (after neuraminidase digestion) and LTA, UEA I, and OOA in the normal group and with PNA (before and after neuraminidase digestion) and LTA and OOA in the pathological one was stronger in the peripheral portion of the jelly with respect to the adventitial one. The reactivity with ConA and UEA I was stronger in the vein than in the arteries in both study groups. Some hypotheses are reported on the role played by the sugar residues in the normal and pathological umbilical cords.

Concanavalin A↗
PubMed2003

Lectin binding in the human foetal testis.

In the present study we have investigated the oligosaccharidic content of the glycoconjugates within the human foetal testis starting from its earliest differentiation phase (8, 10 and 12 weeks of gestation). To this purpose we have used a battery of six horseradish peroxidase-labelled lectins (SBA, PNA, WGA, UEAI, LTA and ConA). We have obtained a complete distributional map of the sugar residues of the glycoconjugates in the coelomic mesothelium, tunica albuginea, pre-Sertoli cells, pre-gonocytes, Leydig cells, basement membrane of the sex cords, interstitial tissue, mastocytes and endothelial cells of the capillary vessels. Since the beginning of the testis differentiation phase the cells of the coelomic mesothelium showed a large amount of sugar residues. In the pre-Sertoli cells and in the pre-gonocytes a role played as structural molecules by some oligosaccharides could be hypothesized. D-galactose-(beta1-->3)-N-acetyl-D-galactosamine, sialic acid, N-acetyl-D-glucosamine and alpha-D-mannose could be involved in inducing and maintaining the cellular activity of the Leydig cells.

Cell Differentiation↗
PubMed2003

CT cystoscopy in the evaluation of bladder tumors.

The aim of the present study was to assess the role of virtual cystoscopy in the identification of bladder tumors. Fifteen patients (11 men and 4 women, median age: 61 years, range: 46-74 years) with a positive finding of bladder tumor at fiber-optic cystoscopy were studied by multislice-CT. Scans were downloaded to a workstation with the aid of a software for the processing of 3-D reconstructions, with a volume-rendering technique which allowed the "navigation" within the bladder in search of wall lesions. In this group of 15 patients, cystoscopy was able to detect 19 neoplastic lesions, 13 with a diameter >10 mm and 6 with a diameter <10 mm. Virtual cystoscopy, instead, identified 17 lesions (89%) only. In particular, all those lesions with a diameter >1 cm (13/13=100%) were correctly identified, whereas only 4 of the 6 lesions with a diameter <1 cm were depicted. The 2 false negative cases were 2 lesions with a flat morphology, measuring 5 and 6 mm. Most recent technological advances allowed the employement of virtual endoscopies, characterized by the absence of invasivity as compared with fiber-optic studies and based on data obtained by spiral- and multislice-CTs. According to our experience, virtual CT-cystoscopy revealed to be a complementary tool in the evaluation of cross-sectional images and proved to be an easy procedure without complications, well-accepted by the patients, and with a reliable detection of those bladder lesions measuring more than 5 mm in case of polypoid formations and at least 10 mm in case of flat lesions. This technique, however, does not allow the collection of a bioptic sample and--with the present resolution power of available equipments--it could be unable to correctly detect small-sized flat lesions. We, nonetheless, believe that this procedure, in the future, thanks to rapid technological improvements in virtual imaging techniques, could become a useful diagnostic tool in the management of those patients with bladder tumors. Further studies on larger study groups are therefore desirable for a more reliable validation of the technique.

Aged↗
PubMed2003

Mesenteric cystic lymphangioma causing intestinal occlusion in an adult patient.

Cystic lymphangioma is a benign tumor of uncertain etiology characterized by a slow growth; in 2-8% of cases it is localized in the mesentery. Symptomatology is aspecific and preoperative diagnosis is often difficult. The Authors report the case of a mesenteric cystic lymphangioma in a patient who had undergone subtotal colectomy eight years earlier for an adenocarcinoma occluding the sigmoid colon. The patient was hospitalized for intestinal occlusion.

Humans↗
PubMed2003

Florid cemento-osseous dysplasia. Report of a case in a white woman with both mandibular and maxillary involvement.

Florid cemento-osseous dysplasia (FLCOD) is a rare pathological entity whose classification is not yet completely defined although its non-neoplastic clinical and histologic behaviour is very clear. FLCOD is a self-limiting lesion scarcely delimited from the surrounding healthy tissue and whose surgical treatment therefore is not elective, unless inflammatory signs are present. A case of a white woman with both mandibular and maxillary involvement is presented; she was referred to us for partial impaction of her lower 3(rd) molars. Standard radiographic and CT images are examined and the patient management is discussed.

Adult↗
PubMed2002

Cumulative effect of complete left bundle-branch block and chronic atrial fibrillation on 1-year mortality and hospitalization in patients with congestive heart failure. A report from the Italian network on congestive heart failure (in-CHF database).

BACKGROUND: Many clinical variables have been proposed as prognostic factors in patients with congestive heart failure. Among these, complete left bundle-branch block and atrial fibrillation are known to impair significantly left ventricular performance in patients with congestive heart failure. However, their combined effect on mortality has been poorly investigated. The aim of this study was to determine whether left bundle-branch block associated with atrial fibrillation had an independent, cumulative effect on mortality for congestive heart failure. METHODS AND RESULTS: We analysed the Italian Network on congestive heart failure (IN-CHF) Registry that was established by the Italian Association of Hospital Cardiologists in 1995. One-year follow-up data were available for 5517 patients. Complete left bundle-branch block and atrial fibrillation were associated in 185 (3.3%) patients. In this population the cause of congestive heart failure was dilated cardiomyopathy (38.4%), ischaemic heart disease (35.1%), hypertensive heart disease (17.3%), and other aetiologies (9.2%). This combination of electrical defects was associated with an increased 1-year mortality from any cause (hazard ratio, HR: 1.88; 95% CI 1.37-2.57) and sudden death (HR: 1.89; 95% CI 1.17-3.03) and 1-year hospitalization rate (HR: 1.83; 95% CI 1.26-2.67). CONCLUSIONS: In patients with congestive heart failure, the contemporary presence of left bundle-branch block and atrial fibrillation was associated with a significant increase in mortality. This synergistic effect remained significant after adjusting for clinical variables usually associated with advanced heart failure. We can conclude that this combination of electrical disturbances identifies a congestive heart failure specific population with a high risk of mortality.

Adolescent↗
PubMed2002

Lectin histochemistry in the human placenta of pregnancies complicated by intrauterine growth retardation based on absent or reversed diastolic flow.

The oligosaccharide distribution of the glycoconjugates was investigated in placental tissue of pregnancies complicated by intrauterine growth retardation (IUGR) with absent or reversed flow in the umbilical artery (ARED), between the 29 and the 37 weeks of pregnancy. Placentae of a gestational age-matched group of normally grown pregnancies was also selected as control group. For this purpose a battery of seven HRP-conjugated lectins was used (DBA, SBA, PNA, ConA, WGA, LTA and UEA I). Our data showed that alpha-D-mannose (ConA), N-acetyl-D-glucosamine (WGA), beta-N-acetyl-D-galactosamine (SBA), alpha-L-fucose (LTA and UEA I) were present in less amount or were not present in the trophoblast and/or in the endothelial cells of the pathological group compared to the control one. The trophoblast basement membrane and/or basal plasma membrane of the pathological placentae were characterized by the presence of alpha-D-mannose (ConA), N-acetyl-D-glucosamine (WGA), sialic acid and D-galactose-(beta1-->3)-N-acetyl-D-galactosamine (neuraminidase-PNA), only in some tracts, in all the weeks of gestation. In the control placentae these sugar residues were present in the whole basement membrane and/or basal plasma membrane from 31 or 35 weeks. The Hofbauer cells of the pathological placental tissue showed a less amount or lack of alpha-D-mannose (ConA), beta-N-acetyl-D-galactosamine (SBA) and alpha-L-fucose (UEA I) compared to the control ones. These results suggest that a less amount or lack of some sugar residues may contribute to restricted placenta growth and development and thus reduced efficiency in maternal-fetal exchanges of gases and metabolites.

Adult↗
PubMed2002

Neutrophilic eccrine hidradenitis secondary to topotecan.

BACKGROUND: Neutrophilic eccrine hidradenitis (NEH) is a self-restricted inflammatory condition, usually secondary to chemotherapeutic agents and less frequently to other drugs such as zidovudine or various infections. NEH clinical features include erythematous, occasionally painful nodules and plaques. Histological examinations reveal neutrophilic infiltrates and degeneration of eccrine glands. METHODS: A 45-year-old female was treated with topotecan and colony-stimulating factor for ovarian cancer. RESULTS: The erythematous and slightly pruritic plaques on the upper and lower limbs and ear lobes appeared approximately 1 week after chemotherapy and spontaneously subsided in about 10 days, only to recur after the next drug dose. A skin biopsy revealed NEH; all skin cultures were negative. CONCLUSION: It is believed that this patient developed topotecan-induced NEH; this relationship with therapy rather than the underlying disease rules out a paraneoplastic reaction, and negative cultures excluded infectious causes. In addition, since skin lesions recurred after CSF was discontinued, this agent was not involved. Studies relating NEH to topotecan, a topoisomerasa I inhibitor, have not reported such an event in the literature.

Antineoplastic Agents↗
PubMed2002

Computed Tomography of dental arches with dedicated software: current state of applications.

Since the introduction of the "Dentascan" reconstruction program, the use of CT in the field of odontostomatology has attracted growing interest from both radiologists and dentists. Over the years, the potential applications of Dentascan have extended from the management of implantology-related issues to the study of all jaw bone diseases relevant to dentists. This paper describes the technical aspects and current diagnostic capabilities of computed tomography of the dental arches with dedicated software, by presenting a wide selection of case studies.

Dental Arch↗
PubMed2002

Adenocarcinoma on horseshoe kidney studied with computed tomography.

Horseshoe kidney is a congenital anomaly of the upper urinary system frequently associated with atypical vascularization, mostly asymptomatic, usually undetected until the onset of infectious, obstructive or neoplastic complications. Although intravenous pyelography and US are useful tools, the role of CT is of vital importance especially in the pre-operative planning of related complications and in those cases where other techniques have correctly diagnosed the disease but have missed the visualization of an underlying malformation. We report here two cases of adenocarcinoma in two patients with a horseshoe kidney, where CT has clearly depicted both the malformation and the associated pathologic findings.

Adenocarcinoma↗
PubMed2001

Purification of the aldehyde oxidase homolog 1 (AOH1) protein and cloning of the AOH1 and aldehyde oxidase homolog 2 (AOH2) genes. Identification of a novel molybdo-flavoprotein gene cluster on mouse chromosome 1.

We report the cloning of the AOH1 and AOH2 genes, which encode two novel mammalian molybdo-flavoproteins. We have purified the AOH1 protein to homogeneity in its catalytically active form from mouse liver. Twenty tryptic peptides, identified or directly sequenced by mass spectrometry, confirm the primary structure of the polypeptide deduced from the AOH1 gene. The enzyme contains one molecule of FAD, one atom of molybdenum, and four atoms of iron per subunit and shows spectroscopic features similar to those of the prototypic molybdo-flavoprotein xanthine oxidoreductase. The AOH1 and AOH2 genes are 98 and 60 kilobases long, respectively, and consist of 35 coding exons. The AOH1 gene has the potential to transcribe an extra leader non-coding exon, which is located downstream of exon 26, and is transcribed in the opposite orientation relative to all the other exons. AOH1 and AOH2 map to chromosome 1 in close proximity to each other and to the aldehyde oxidase gene, forming a molybdo-flavoenzyme gene cluster. Conservation in the position of exon/intron junctions among the mouse AOH1, AOH2, aldehyde oxidase, and xanthine oxidoreductase loci indicates that these genes are derived from the duplication of an ancestral precursor.

Aldehyde Oxidoreductases↗
PubMed2001

Hemophilic arthropathy. A scoring system for magnetic resonance imaging.

The aim of this study was to define a system for scoring hemophilic arthropathy (HA) based on MR findings, providing for objective evaluation of the degree of joint involvement and evolution after on-demand administration of FVIII substitutional therapy or prophylactic treatment. A total of 133 MR examinations (89 basal and 44 during follow-up) were performed in 25 patients. Patients were divided in two groups depending on the therapy received and the length of time that the disease had been evolving at the start of the study. Group I was composed of 10 patients with secondary prophylaxis and group II was composed by 15 treated on demand. T1-weighted and T2*-weighted images performed on a 0.5-T unit were prospectively evaluated. The joint involvement was established on a scale of 0 (no abnormalities), I (minimal amount of hemosiderin), II (large amount of hemosiderin and isolated cartilaginous erosion), III (cartilage destruction, bone erosions, and subchondral cysts) to IV (large internal joint derangement, secondary osteoarthritis and/or ankylosis). At basal MR examination, patients of group I showed no abnormalities ( n=28, 75.6%), grade I ( n=3), and grade II ( n=6) of HA. Patients of group II corresponded to MR grades III ( n=21) and IV ( n=11) of HA. The MR follow-up showed improvement in three joints of group I and worsening in 5 joints in group I and 2 joints in group II. Early signs of HA were detected in 10 joints with MR imaging but were underestimated on plain radiographs. Advanced degrees of HA were classified as severe under both imaging techniques. Magnetic resonance is the preferred imaging technique to assess HA. The earliest signs of joint damage, detected by MR, are overlooked by plain radiography. The MR scoring system can be used for evaluating HA. Follow-up MR should be performed to evaluate regression or worsening of the abnormalities, primarily in the case of patients with prophylaxis who usually suffer normal or early joint involvement not detected by other means.

Adult↗
PubMed2001

Overexpression of functionally coupled cyclooxygenase-2 and prostaglandin E synthase in symptomatic atherosclerotic plaques as a basis of prostaglandin E(2)-dependent plaque instability.

BACKGROUND: Studies have implicated a role for prostaglandin (PG) E(2)-dependent matrix metalloproteinase (MMP) biosynthesis in the rupture of atherosclerotic plaque. Cyclooxygenase-2 (COX-2) and PGE synthase (PGES) are coregulated in nucleated cells by inflammatory stimuli. The aim of this study was to characterize the expression of COX-2 and PGES in carotid plaques and to correlate it with the extent of inflammatory infiltration and MMP activity and with clinical features of patients' presentation. METHODS AND RESULTS: Plaques were obtained from 50 patients undergoing carotid endarterectomy and divided into 2 groups (symptomatic and asymptomatic) according to clinical evidence of recent transient ischemic attack or stroke. Plaques were analyzed for COX-2, PGES, MMP-2, and MMP-9 by immunocytochemistry and Western blot, whereas zymography was used to detect MMP activity. Immunocytochemistry was used to identify CD68+ macrophages, CD3+ T lymphocytes, and HLA-DR+ cells. The percentage of macrophage-rich areas was larger (P<0.0001) in symptomatic plaques. COX-2, PGES, and MMPs were detected in all specimens; enzyme concentration, however, was significantly higher in symptomatic plaques. COX-2, PGES, and MMPs were especially noted in shoulders of symptomatic plaques, colocalizing with HLA-DR+ macrophages. All symptomatic plaques contained activated forms of MMPs. Finally, inhibition of COX-2 by NS-398 was accompanied by decreased production of MMPs that was reversed by PGE(2). CONCLUSIONS: This study demonstrates the colocalization of COX-2 and PGES in symptomatic lesions and provides evidence that synthesis of COX-2 and PGES by activated macrophages is associated with acute ischemic syndromes, possibly through metalloproteinase-induced plaque rupture.

Aged↗
PubMed2001

Modulation of caspase-3 activity by zinc ions and by the cell redox state.

It is known that DNA fragmentation during apoptosis is controlled by a number of factors, a crucial step being the caspase-operated cleavage of ICAD, the DNase inhibitor. We have previously demonstrated that hydrogen peroxide-treated lymphocytes undergo apoptosis without formation of a DNA ladder; however, the use of micromolar amounts of a Zn(2+) chelator allowed DNA cleavage at internucleosomal sites. Such results were extended in the present work, thus allowing their framing into the events related to alterations in the redox state of the cell. Apoptosis in hydrogen peroxide-treated lymphocytes was found to occur with caspase-3 activation, but the enzyme activity was found to be impaired, thus affecting internucleosomal fragmentation as well as nuclear morphology. Caspase-3 activity was found to resume upon mild Zn(2+) chelation. These results provide as well an experimental model from which apoptotic events upstream and downstream of caspase-3 activity can be examined.

Adult↗