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Biomedical subjects

R Marino

Publications and source records attributed to R Marino.

At least 55 records · Page 3Linked to original sources
PubMed1999

Influence of factor VIII/von Willebrand complex on the activated protein C-resistance phenotype and on the risk for venous thromboembolism in heterozygous carriers of the factor V Leiden mutation.

High factor VIII plasma levels have been shown to represent a common increased risk for venous thromboembolism (VTE) and may cause an activated protein C (APC) resistance in the absence of the factor V Leiden mutation, but there are no studies specifically aimed to establish if high factor VIII and von Willebrand factor (vWF) concentrations may influence the APC sensitivity ratio (APC-SR) and increase the risk for VTE in the presence of the factor V Leiden mutation. For this purpose, we performed a retrospective case-control study to investigate the influence of the procoagulant factor VIII (VIII:C) and the antigen of vWF (vWF:Ag) on the normalized APC-SR (n-APC-SR) and on the risk for VTE, in two selected groups of 30 symptomatic (Group I) and 32 asymptomatic (Group II) related heterozygotes for the factor V Leiden mutation. Differences between the two groups (Group I versus Group II) were: n-APC-SR, 0.57+/-0.06 versus 0.63+/-0.08, P = 0.001; factor VIII:C, 1.49+/-0.42 versus 1.13+/-0.28 IU/ml, P<0.001; vWF:Ag, 1.46+/-0.53 versus 1.26+/-0.32 IU/ml, NS. As a whole (Group I + Group II), Pearson correlation coefficients were: n-APC-SR versus factor VIII:C, r = -0.410, P = 0.001; n-APC-SR versus vWF:Ag, r = -0.309, P = 0.01; factor VIII:C versus vWF:Ag, r = +0.640, P<0.0001. The relative risk for VTE in individuals with the factor VIII:C concentration > 1.5 IU/ml was 2.5 (95% confidence interval 1.6-3.9). We concluded that high factor VIII:C levels, probably in the effect of vWF, play a determinant role in worsening the APC-resistance phenotype and represent a common additional risk factor for VTE in heterozygous carriers of the factor V Leiden mutation.

Adult↗
PubMed1999

Oral health in children and adolescents with IDDM--a review.

Children with insulin-dependent diabetes mellitus have a lower salivary flow rate, pH and buffer capacity, but a higher glucose content and peroxidase, IgA, magnesium and calcium concentration, in comparison with healthy children. Nevertheless the incidence of caries is lower than normal in diabetic children with good metabolic control. Periodontal disease usually starts at puberty as mild gingivitis with bleeding and gingival recession, and it may develop into severe periodontitis, especially in children with poor control of diabetes. Microangiopathy, impaired immune response, different bacterial microflora and collagen metabolism are involved in the pathogenesis of diabetic periodontal disease. The gingival flora is mostly composed of Gram-negative, anaerobic bacteria, while collagen has a lower solubility and is atrophic and inadequate to support the occlusion forces. For these reasons, prevention of periodontitis is important in diabetic children; they should receive oral hygiene instruction and visit a dentist at least twice a year.

Adolescent↗
PubMed1998

Identification and developmental expression of Ci-isl, a homologue of vertebrate islet genes, in the ascidian Ciona intestinalis.

Here we describe the cloning and expression pattern of Ci-isl, a homologue of vertebrate genes, in the ascidian. Early in development, Ci-isl expression occurs in the primordia of palps and brain vesicle, then in the tailbud embryo it is transiently extended to the notochord cells. At larva stage, the expression is down-regulated in the notochord, and it persists predominantly in the compartments of the nervous system. These observations indicate that also in invertebrates, islet genes show an expression pattern during differentiation of the nervous system.

Animals↗
PubMed1998

The hsp70 protein is involved in the acquisition of gamete self-sterility in the ascidian Ciona intestinalis.

In the hermaphrodite ascidian Ciona intestinalis, gamete self-incompatibility is a mechanism that prevents self-fertilization and is based on the ability of the oocyte vitelline coat to distinguish and accept only heterologous spermatozoa. The onset of self-sterility occurs during oogenesis and involves or is controlled by the follicle cells. Gamete self-nonself discrimination, a process that can be likened to an immune recognition event, represents a useful model with which to study the evolution of self-nonself recognition. Hsp70 genes, which belong to the major histocompatibility complex (MHC) class III, are supposedly ancestors of the MHC class I and II genes, and chaperonins are known to be involved in antigen processing and presentation. We have isolated and characterized an hsp70 gene (Cihsp70) that is constitutively expressed during oogenesis in the follicle cells of previtellogenic and vitellogenic oocytes. Using a polyclonal antibody against Cihsp70 protein, we demonstrate that the expression of Cihsp70 is required for the switch from self-fertility to self-sterility. The functional involvement of Cihsp70 in gamete self-nonself recognition provides evidence for an ancestral MHC-like system in protochordates.

Amino Acid Sequence↗
PubMed1997

Effects of acute or chronic administration of risperidone on motor and sexual behavior of male rats.

A number of experiments were carried out to explore the behavioral profile of a novel antipsychotic, risperidone, after acute or chronic administration, in a dose range of 0.1-10 mg kg-1. This drug did not affect the acquisition and retention of avoidance behaviors in a dose of 0.1 mg kg-1, either after acute or chronic administration. Higher doses induced a inhibited acquisition and a facilitated extinction (only after chronic treatment) of active avoidance behavior, but no significant effect on the retention of passive avoidance responses. In contrast, haloperidol inhibited the acquisition and facilitated the extinction of active avoidance behavior, and reduced the retention of passive avoidance reaction at the dose of 0.1 mg kg-1 injected either acutely or chronically. Ambulation and rearing of rats rated in an open field was increased by risperidone injected acutely at the dose of 1 mg kg-1. Under the same experimental conditions, grooming appeared to be reduced. In the same test, acute or chronic haloperidol 1 or 10 mg kg-1 inhibited all behavioral items. Furthermore, in contrast to haloperidol, the acute or chronic administration of risperidone in a dose range of 0.1-10 mg kg-1 did not substantially induce catalepsy and did not affect apomorphine-induced stereotypies. Also, the dose of 0.1 mg kg-1 induced a facilitation of male sexual behavior by increasing the frequency and reducing the latency of mountings, intromissions and ejaculations, while haloperidol 1 or 10 mg kg-1 inhibited this behavior. These findings suggest that the pharmacological profile of risperidone differs from that of classical neuroleptics, like haloperidol, probably due to different mechanism or site of action.

Analysis of Variance↗
PubMed1997

CD70 expression on T-cell subpopulations: study of normal individuals and patients with chronic immune activation.

CD70, the ligand of CD27, is a member of the TNF family, which includes molecules essential in the regulation of lymphocyte growth and survival. It is absent on resting lymphocytes but can be induced in vitro with activating stimuli. To extend information about its expression by different T-cell subpopulations, and its regulation in normal and pathologic conditions, highly purified T-cell subpopulations were studied: CD70 expression depended both on the activating stimulus and on the T-cell subset analyzed. PMA + Ionomycin induced CD70 on the large majority of CD8+ cells, but only on a minority of CD4+ cells (P < 0.002), and among these, preferentially on the CD45R0+ subset compared with the CD45RA+. The presence of CD4+ lymphocytes in cell cultures containing mixtures of T-cell subsets inhibited CD70 expression on CD8+ cells. On the contrary, stimulation with allogeneic cells induced CD70 expression also on CD4+ cells. Moreover, CD70 was found to be expressed by chronically in vivo activated T-cells, in conditions characterized by allogeneic and autoimmune reactions. These data suggest a possible role of CD70 in the pathogenesis of immune dysregulation; interestingly, this role may not be simply restricted to bind to, and signal through, CD27, since cross-linking of CD70 enhances the proliferative response induced by the stimuli used to elicit its expression.

Antigens, CD↗
PubMed1997

Chronic encephalitis and epilepsy in adults and adolescents: a variant of Rasmussen's syndrome?

Chronic encephalitis and epilepsy (Rasmussen's encephalitis) is a rare progressive disorder of uncertain etiology that usually occurs in children, producing focal epilepsy, hemiparesis, and intellectual deterioration. We identified 13 patients in whom seizures developed in adolescence or adulthood with a pathologic picture of chronic encephalitis. The clinical characteristics were more variable than those occurring in children, with the patients falling into three groups: five patients developed seizures in adulthood, but otherwise showed many resemblances to the childhood form; five developed seizures in adolescence, with similar presentation but rather more benign course than in the younger patients; and three presented with clinical features initially suggestive of a tumor. Occipital onset to the seizures appeared to be more common than in the childhood form, and bilateral disease also occurred.

Adolescent↗
PubMed1996

Monoamines and their metabolites in cerebrospinal fluid and temporal cortex of epileptic patients.

The involvement of monoamines in the initiation or maintenance of epileptic phenomena has been extensively studied in cerebral tissues and in cerebrospinal fluid. The present work was undertaken to study monoamines and their metabolites in human spiking and non-spiking temporal cortex excised from patients with complex partial seizures unresponsive to available anticonvulsants. The same substances were also analyzed by HPLC-ED in cerebrospinal fluid obtained 24 h before the surgical procedure and compared with those from patients with chronic headache and normal neurological evaluation. The results show increased 5-HT, 5-HIAA and HVA levels in spiking compared with non-spiking cortex. Cerebrospinal fluid levels of 5-HIAA and HVA are concomitantly increased in epileptic compared with headache patients.

Adult↗
PubMed1995

Transient mutism following a posterior fossa approach to cerebellar tumors in children: a critical review of the literature.

Transient mutism has been known as a rare complication following a posterior fossa approach to cerebellar tumors and its cause has not been clearly elucidated. The cerebellar mutism is not accompanied by cranial nerve deficits and disorders of consciousness. Since 1985 only 23 cases of mutism following removal of a cerebellar tumor in children have been reported in the literature. Two additional cases have been operated upon in our department. Extensive injury to the vermian and paravermian cerebellar area, involving the hemispheric cortex, cerebellar peduncles, fibers from the dentato-thalamocortical pathway, and dentate and interpositum nuclei may be the most important anatomical substrate of mutism. The mechanism of such transient mutism seems to be a complex of two or more factors (vascular disturbances due to manipulation or retraction of the cerebellar region around the IV ventricle and emotional factors). On the basis of these 25 cases the major features of the cerebellar mutism are discussed.

Ataxia↗
PubMed1994

Epilepsy: principles of surgical management.

In his keynote address, the author reviews early work in the surgical management of the epilepsies and presents a state-of-the-art review of current basic science and clinical indications for and results from corpus callosotomy for the treatment of seizure disorders.

Corpus Callosum↗
PubMed1992

Purification and characterization of a vitelline coat lysin from Ciona intestinalis spermatozoa.

In Ciona intestinalis a chymotrypsin-like activity is involved in sperm penetration of the egg vitelline coat. A chymotrypsin-like enzyme has been purified from spermatozoa by a protocol including ion exchange chromatography, gel filtration, and native polyacrylamide gel electrophoresis. The purified enzyme resulted homogeneous when analyzed by SDS-PAGE. The molecular weight of the chymotrypsin-like enzyme was estimated to be 35 kDa by gel filtration and 24 KDa by SDS-PAGE in nonreducing conditions. The pH optimum of the enzyme is 8.4 and its activity is enhanced by Ca2+. It shows the highest activity towards the synthetic substrate Suc-Ala-Ala-Pro-Phe-AMC. Furthermore, by electron microscopy, the purified enzyme affects the structure of egg vitelline coat, and thus it fulfills one of the criteria of a lysin.

Amino Acid Sequence↗
PubMed1992

Evidence that metalloendoproteases are involved in gamete fusion of Ciona intestinalis, ascidia.

The use of specific inhibitors and substrates of metalloendoproteases provides evidence that in many systems these enzymes are involved in membrane fusion events. In this study, we investigated whether metalloendoproteases are involved in Ciona sperm-egg fusion. In vitro fertilization assays with the metal chelator 1,10-phenanthroline, specific metalloendoprotease substrates, and the vital stain Hoechst 33342 suggested that a Zn(2+)-dependent metalloendoprotease(s) takes part in Ciona sperm-egg fusion. Furthermore, electrophysiological recordings showed that insemination carried out in the presence of either 1,10-phenanthroline or the substrate CBZ-Gly-Phe-NH2 fails to induce fertilization potential or any other change in membrane potential. These results support the hypothesis that in Ciona intestinalis, a metalloendoprotease(s) is functional in gamete fusion.

Animals↗
PubMed1991

Human papillomavirus DNA in cervical intraepithelial neoplasia detected by in situ hybridisation.

Human papillomavirus (HPV) infection was investigated by in situ hybridisation in histological sections from 38 women with abnormal Papanicolaou smears. 13 patients had condylomatous lesions without atypia, 15 cervical intraepithelial neoplasia (CIN) I, 4 CIN II, 3 CIN III and 2 carcinoma in situ (CIS). HPV DNA was detected in 29 cases (78%) (1 specimen was technically inadequate). HPV 16 and 18, and 31, 33 and 35 were both present (67%) in CIN III. HPV 6 and 11 were more frequent in CIN I (56%) and in condylomatous lesions (38%). 31% of the condylomatous lesions without atypia contained HPV 31, 33, and 35 and 31% of those with CIN I were infected with HPV 16 and 18. These data confirm the frequent association of HPV infection with cervical cancer and CIN, and indicate that in situ hybridisation can identify patients with specific types of HPV infection at risk for cervical cancer.

Adult↗
PubMed1990

Chymotrypsin-like enzymes are involved in sperm penetration through the vitelline coat of Ciona intestinalis egg.

In Ciona intestinalis, sperm penetration through the egg vitelline coat is an essential event of fertilization. We investigated whether trypsin- and chymotrypsin-like enzymes are involved in this event. Inhibitors and peptide substrates for chymotrypsin-like enzymes blocked the overall process of fertilization in a concentration-dependent manner. The inhibitory activity was specifically exerted on the step of sperm penetration. Chymotrypsin-like protease activity was identified in spermatozoa with the fluorogenic synthetic substrate Suc-Ala-Ala-Phe-AMC, which was the most effective substrate in blocking sperm penetration. These data indicate that a chymotrypsin-like protease activity is a sperm lysin of Ciona intestinalis.

Amino Acid Sequence↗
PubMed1990

Selective electroencephalograph-guided microsurgical callosotomy for refractory generalized epilepsy.

Between 1978 and 1985, 35 patients with medically refractory multiform seizures were submitted for sections of variable portions of the corpus callosum. Guided by intraoperative electroencephalographic and electrocorticographic monitoring, the section was carried out only in the portion of callosum that was involved in the maintenance of the bilaterally synchronous slow spike and wave discharge (as documented by intraoperative electrocorticography). In our patients, only part of the frontal corpus callosum needed to be sectioned to interrupt the bilateral synchrony of epileptic discharge. Of the 35 patients, operated on, 28 have had an adequate long-term follow up and are presented herein. All had significant improvement in seizure frequency and psychosocial functioning.

Adolescent↗