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Biomedical subjects

G Ottaviani

Publications and source records attributed to G Ottaviani.

At least 19 recordsLinked to original sources

Expression of apoptosis and proliferating cell nuclear antigen (PCNA) in the cardiac conduction system of crib death (SIDS).

Aim of this study is to determine the expression of apoptosis and Proliferating Cell Nuclear Antigen (PCNA) in the cardiac conduction system in crib death and explained death (ED) cases. Postnatal morphogenesis of the conducting tissue is an important part of its normal development. In the atrio-ventricular node (AVN) and His bundle (HB) it consists of degeneration, cell death and replacing in an orderly programmed way. However, its nature and its relation to crib death is not yet fully explained. Apoptosis and PCNA were investigated in 8 heart conduction systems of infants dying of crib death and in 3 conduction systems of infants dying of ED as controls. The cardiac conduction system was removed in two blocks: the first included the sino-atrial node (SAN) and the crista terminalis, the second contained the atrio-ventricular node (AVN), His bundle (HB), bifurcation, and bundle branches. In the conduction systems as well as in the common myocardium the PCNA Labeling Index (PCNA-LI) was found to be negative in all cases. The apoptotic indices (AI) in SIDS and in ED were found to have no statistically significant differences (p>0.05). The SAN, in both groups, showed an AI similar to the one detected in common myocardium. In almost all cases, TUNEL labeling was detected in peripheral region of the AVN, close to the atrial myocardium. The AI was higher in the AVN, HB and the initial tract of bundle branches than in the common myocardium (p<0.05; Student's t test).

Apoptosis↗

The prognostic value of cell proliferation in colorectal adenomas assessed with tritiated thymidine and anti-proliferating cell nuclear antigen.

We analyze the cell kinetics of colorectal adenomas by tritiated thymidine (3HTdR) autoradiographic method and anti-proliferating cell nuclear antigen (PCNA) antibodies. A total of 46 patients who underwent prior endoscopic polypectomy for colorectal adenomas were reevaluated by colonoscopy for 4 years. Thymidine labeling index (T-LI) in index adenomas ranged from 1.40 to 38.0% (median value: 10. 75%); PCNA labeling index (PCNA-LI) in index adenomas ranged from 0 to 27.0% (median value: 1.95%). Among the 46 patients studied, 16 developed recurrent adenomas (Group A) and 30 were free of recurrent adenomas (Group B). The T-LI and PCNA-LI comparisons between Groups A and B were statistically significant (p < 0.0001, chi2 test). These results demonstrate that T-LI and PCNA-LI in colorectal adenomas might be helpful to predict the development of metachronous adenomas and hence to plan the follow-up of patients with adenomatous polyps after polypectomy.

Adenomatous Polyps↗

Proliferating cell nuclear antigen (PCNA) and apoptosis in hyperacute and acute myocardial infarction.

The aim of this study was to determine whether cell proliferation and/or apoptotic cell death occur in hyperacute and acute infarction. Proliferating cell nuclear antigen (PCNA) and apoptosis were investigated in ten autoptic hearts within a few hours of infarction and in three normal hearts as controls. The PCNA Labeling Index (PCNA-LI) ranged from 0 to 3.1 in hyperacute infarction (mean 1.38), from 0.3 to 4 in acute infarction (mean 2.04) and from 0 to 1.2 in controls (mean 0.7). Although the results were not statistically significant, PCNA-LI was higher in acute than in hyperacute myocardial infarctions; and it was higher in hyperacute infarctions than in controls. Regarding apoptosis, the Apoptotic Index (AI) in hyperacute infarctions ranged from 0.7 to 3 (mean 1.78), in acute infarctions from 0.9 to 5 (mean 3.24) and in controls from 0 to 0.4 (mean 0.1). The AI was significantly higher in hyperacute and acute infarctions than in controls (p < 0.05).

Aged↗

Discrete T-lymphocytic leptomeningitis of the ventral medullary surface in a case of Sudden Unexpected Infant Death.

The Authors report the case of a 4 month old female infant dying suddenly and unexpectedly. At post-mortem examination, nothing significant was found, except a focal T-lymphocytic brainstem leptomeningitis, involving the ventral medullary surface (VMS) particularly coincidental with the pyramids, with involvement of the outer layer of the nucleus arcuatus (NARC). Moreover, the NARC itself presented, on serial sections, interdigitated subdivisions. To the present authors' best knowledge, no case has been recordered in the literature, as yet, exhibiting VMS inflammation, evidently acquired (likely viral) in nature, associated to a NARC developmental defect, altogether bespeaking for the etio-pathogenic importance of such a combined pathology of the central chemosensitive field among the long debated mechanisms of SIDS.

Journal Article↗

[Dispersion of junctional tissue and its consequences in a case of sudden infant death].

This article reports a case of sudden infant death syndrome in a 1-month-old male. Some important abnormalities of the cardiac conduction system were found, consisting of persistent fetal dispersion of the atrioventricular node and His bundle, accessory atrioventricular pathways of Mahaim type and resorptive degeneration. These changes could be considered as a morphological substrate for cardiac arrhythmias.

Atrioventricular Node↗

Hyperplasia of the aorticopulmonary paraganglia: a new insight into the pathogenesis of sudden infant death syndrome?

In this study, the Authors search for morphologic alterations in the aorticopulmonary paraganglia (APP) of sudden infant death syndrome (SIDS) victims when compared with age-matched controls. Morphometric studies on serial sections of the APP were performed with an image analyzer in combination with a standard microscope attached to a video camera. APP hyperplasia, characterized by an increase in some parameters such as number, mean lobule diameter and total glomic tissue volume when compared with age-matched controls, was observed in 23.8% of SIDS victims. Similar alterations have been reported in peripheral chemoreceptors of animals and human beings who are chronically hypoxemic. In SIDS, it could reflect an abnormal chemoreceptor function, contributing to an altered respiration control.

Age Factors↗

Simultaneous determination of cotinine and trans-3'-hydroxycotinine in human serum by high-performance liquid chromatography.

A high-performance liquid chromatographic method with ultraviolet photometric detection has been developed for the quantitation of cotinine and trans-3'-hydroxycotinine in human serum. A solid-phase extraction procedure was performed for the analytes and the internal standard, N-ethylnorcotinine, before chromatography. The use of a 30-cm reversed-phase column and a mobile phase of water-methanol-0.1 M sodium acetate-acetonitrile (67:24.5:6.5:2, v/v), pH 4.3, prevented the co-elution of caffeine with cotinine. The limit of quantitation observed with this method was 5 ng/ml for both cotinine and trans-3'-hydroxycotinine. The present method proved useful for the determination of serum levels of these metabolites, correlating with nicotine daily intake.

Chromatography, High Pressure Liquid↗

How the steady-state cotinine concentration in cigarette smokers is directly related to nicotine intake.

The relationship between nicotine intake and steady-state cotinine concentration was studied in a sample of 125 subjects who smoked their usual brands of cigarettes. Nicotine and tar yield of cigarettes was determined with a smoking machine, under standardized conditions. Blood was drawn about 8 hours after the last cigarette was smoked and serum cotinine was measured by high performance liquid chromatography. Cotinine levels ranged from 11 to 400 ng/ml, and nicotine daily intake ranged from 1 to 33 mg/day. Regression analysis and the correlation coefficient, r = 0.919, significant at p less than 0.0001, showed that steady-state cotinine level was linearly and directly related to daily available nicotine, with an increase in correlation coefficient directly related to the increase in tar and nicotine yield. From the findings we also conclude that smokers of low-tar cigarettes do not tend to compensate for lower yields of nicotine.

Adolescent↗

Characterization of bioacceptable carbon materials.

Bioacceptable carbon films deposited with a new low temperature technique have been investigated using Raman and X-ray photoelectron spectroscopy. Our results reveal a substantial similarity between the low temperature deposited film and the well-known bioacceptable low temperature isotropic (LTI) pyrocarbon. The Raman spectra, as well as the larger density and oxygen content in the bulk, lead to the speculation of the presence of the common tetrahedral bonds in these materials.

Carbon↗