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Biomedical subjects

M Marchetti

Publications and source records attributed to M Marchetti.

At least 127 records · Page 7Linked to original sources
PubMed1994

Mitochondrial activities of rat heart during ageing.

Some analytical and functional parameters of rat heart mitochondrial have been investigated at six different periods of ageing from 2 to 26 months. The fatty acid composition of the mitochondrial membranes reveals a percentage increase of polyunsaturated fatty acids (20:4 n-6, 22:6 n-3) up to 12 months, followed by a decrease; however, fluorescence polarization of the membrane probe diphenylhexatriene is not changed, revealing that membrane fluidity is not significantly affected. No major change in ubiquinone-9 and in cytochrome content is apparent, indicating that the relative ratio of the respiratory chain components is unmodified. Nevertheless, significant changes in enzyme specific activities are detected: NADH cytochrome c reductase and cytochrome oxidase activities increase up to 12 months, then decrease at 18-26 months; ubiquinol cytochrome c reductase exhibits a peak at 18 months, followed by a decrease. All these activities follow a similar trend during the whole life span of the rat, even though the 'maximum' is different. No significant changes have been found in ATP synthase. Succinate-cytochrome c reductase steadily increases over the whole life span. The results, showing activity decreases in the respiratory enzymes having subunits encoded by mitochondrial DNA, are compatible with the 'mitochondrial' theory of ageing.

Aging↗
PubMed1994

Uptake and distribution of exogenous CoQ in the mitochondrial fraction of perfused rat liver.

The system of perfusing rat livers has been used to evaluate the uptake and incorporation of liposomal CoQ10 into mitochondria. After 90 minutes of perfusion the cells are strongly enriched in CoQ10 up to levels of the same order of magnitude as CoQ9. Heavy and light mitochondrial crude subcellular fractions, low in CoQ10 in control livers, contain high amounts of the quinone after perfusion; yet the purification of these fractions on a metrizamide gradient reveals that the exogenous quinone is mainly associated with the light mitochondrial subfraction, enriched in lysosomes. An increase of the NAD-dependent glutamate-malate oxidase activity is observed in CoQ10 perfused animals. As the total levels of CoQ9 + CoQ10 in these animals are not significantly modified by the CoQ10 incorporated, the observed higher activity is not ascribable to an integration of exogenous quinone into the ubiquinone pool. An antioxidant effect of extramitochondrial CoQ10 on mitochondrial functions is suggested.

Animals↗
PubMed1994

Risk factors for breast cancer. Case-control study results.

The great importance of knowing the risk factors for breast pathology in order to reveal the risk categories is well known. In many geographical areas breast cancer is the most common female neoplasm. Recent Italian statistics point out that every year 83 women out of 100,000 develop breast cancer and that its incidence is increasing. Every year in Italy 10,000 women die of breast cancer. In our retrospective study 146 women suffering from breast cancer, treated in our Institute from 1970 to 1993, were enrolled. We excluded 4 patients, surgically treated in another Institute and 35 who presented a second or a third gynaecological cancer. We considered age, menarche, parity and menopausal age in all patients in order to evaluate the association of these risk factors with breast cancer development. The average age when neoplasm was first diagnosed was 53.07 years (between 30-84 years), with a 9.4% incidence in patients under 35 years old. In 41.1% of the cases, menarche was present under 12 years and in only 14.1% after 14 years, therefore confirming the reduction of mammary cancer risk in women with late menarche. Twenty one point five per cent of the patients were nulliparous. In our case series no protective factor seemed to be related with 1 or 2 pregnancies (43.9%). The menopausal average age was 50.2, with an average fertile life period of 37.1 years. Our study also considered the location of the primary neoplasia (60.7% in the upper-outer quadrant), the tumor size (3.08 cm average diameter) and the histological type (81.3% ductal form).(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗
PubMed1994

Interaction among dietary vitamin B6, proteins and lipids: effects on liver lipids in rats.

Vitamin B6 is involved in protein and lipid metabolism. Yet the effect of pyridoxine deficiency has been studied in relation to separate dietary parameters, we aim to investigate the effect of pyridoxine deficiency associated with a high intake of proteins and/or low EFA content in the diet. Vitamin B6 and PLP contents, fatty acid compositions of lipids and phospholipids were determined in liver of groups of rats fed on diets with different amounts of proteins (20-40%) and EFA (2-35%). The results show a complex interaction among tested nutritional factors with a prevailing influence of dietary proteins on lipid content of liver and of low EFA intake and vitamin B6 on PUFA metabolism. The effects of pyridoxine deficiency on lipid metabolism were dependent on the EFA content of the diet.

Animals↗
PubMed1994

Surgical strategies in vulvar cancer.

The evolution of surgical strategies in vulvar cancer over thirty years of personal experience is considered. The knowledge of aggressiveness and risk factors of every tumor correlated with the patients' age allows today to perform adequate radical surgery even without the large multilations of the past. 5-year survival rate and incidence of relapses are the same while quality of life is highly improved. The Authors stress the new conservative trend in every field of oncological surgery.

Female↗
PubMed1994

Protective effect of exogenous coenzyme Q against damage by adriamycin in perfused rat liver.

We have investigated the effect of rat liver perfusion with adriamycin on mitochondrial activities. Although the perfusion treatment per se induces some decline of respiratory activities, adriamycin strongly potentiates this effect; moreover the coenzyme Q9 content of the mitochondrial membrane is significantly lowered by the antibiotic. Coaddition of coenzyme Q10 in the perfusate significantly protects the mitochondria, not only from loss of respiratory activities but also of the endogenous CoQ9 content. Exogenous CoQ10 fails to enhance respiratory activities in control rats, not treated with adriamycin, even though CoQ concentration has been proven not to be kinetically saturating in the respiratory chain under physiological conditions. Thus, the beneficial effect of CoQ10 in the perfusate does not appear to be the result of its role in the respiratory chain but is a consequence of its antioxidant action.

Animals↗
PubMed1994

Rotavirus and poliovirus co-infection in HT-29 cells.

The effect of a mixed poliovirus-rotavirus infection in HT-29 cells, a gut tumour derived cell line highly susceptible to both viruses, has been analyzed. The obtained results showed an increase of poliovirus multiplication in cells super-infected or co-infected with rotavirus, whereas the pre-infection with poliovirus had an interfering effect on rotavirus replication.

Antigens, Viral↗
PubMed1994

Ovarian teratomas. An analysis of 134 cases.

All ovarian teratomas observed from 1979 to 1989 in the Institute of Pathology University of Padua are revised. Mature and immature teratomas are analyzed separately because of their different prognoses.

Adolescent↗
PubMed1994

Invasiveness of Shigella flexneri in poliovirus infected HT-29 cells.

In this paper we report the effect in HT-29 cells of mixed infections with poliovirus type 1 and Shigella flexneri serotype 5 strain M90T and derivative strains differing in adhesive as well as invasive properties. HT-29 epithelial intestinal cells derived from a human colon adenocarcinoma are a good model for coinfection studies because they are susceptible both to poliovirus replication and to S. flexneri invasion. The results show that 48 h after infection by poliovirus the invasiveness of wild-type S. flexneri M90T and of its adherent and invasive derivative M90T (pIL22) is increased. However, the alterations produced in HT-29 cells at the later stage of poliovirus infection are not sufficient to promote the internalization of simply non invasive, or non invasive but adherent, isogenic derivative bacterial strains.

Bacterial Adhesion↗
PubMed1994

Cancer procoagulant in the human promyelocytic cell line NB4 and its modulation by all-trans-retinoic acid.

Acute promyelocytic leukemia (APL) cells express different types of procoagulant activity (PCA), including tissue factor (TF), and cancer procoagulant (CP). The aim of this study was to investigate whether the NB4 cell line, the first ever isolated human APL line, with the typical t(15;17) chromosomal balance translocation, possess CP as well as the cells freshly isolated from APL patients. Secondly, since the NB4 line is maturation inducible by all-trans-retinoic acid (ATRA), we wanted to verify whether CP, if present, was affected by ATRA treatment. The NB4 cells were able to shorten the recalcification assay of normal human plasma (total PCA). To distinguish CP in the assay for clotting activity, two criteria were used, the independence from factor VII to trigger blood coagulation and the sensitivity to cysteine proteinase inhibitors. Forty-seven per cent of total PCA of cell extracts was found to be FVII-independent PCA. A similar proportion of FVII-independent activity (42%) was detected in the cell serum-free supernatants. The activity was significantly decreased by cysteine proteinase inhibitors, including HgCl2, lodoacetic acid and Z-Ala-AlaCHN2. Additionally CP was directly identified and quantified by an immunocapture enzyme assay. The mean +/- SD concentration of CP detected by this assay in the NB4 cells, before any treatment, was 1.89 +/- 0.5 microgram/mg protein. Treatment of NB4 cells with 10(-6) M ATRA for 5 days significantly decreased the expression of CP, which became virtually undetectable by the clotting assay, and was 64% less than the untreated control by the immunocapture enzyme assay. This study provides the first evidence that the human promyelocytic cell line NB4 possess CP. The expression of this procoagulant is modulated by ATRA.

Blood Coagulation Factors↗
PubMed1993

Interaction between vitamin B6 deficiency and low EFA dietary intake on kidney phospholipids and PGE2 in the rat.

Vitamin B6 is involved in the metabolism of long chain polyunsaturated fatty acids and phospholipids. We have studied the interaction between pyridoxine deficiency and low amounts of dietary essential fatty acids (EFA) in the rat. The fatty acid composition of kidney phospholipids of pyridoxine deficient animals shows a decrease of 20:3 n9 and an increase of 20:4 n6 in comparison with control and pair fed animals. This variation of fatty acid composition could be due to the simultaneous effect of vitamin B6 deficiency, which reduces the oxidation of linolenate, and of a low intake of EFAs which stimulates delta-6-desaturase. The dietary treatment also influences kidney Prostaglandin E2 (PGE2) levels which are higher in vitamin B6 deficient animals. This effect could be correlated with a higher response to sympathetic stimulation caused by the simultaneous presence of vitamin B6 deficiency and low EFA availability. Also the higher level of arachidonate could be involved in promoting PGE2 synthesis.

Animals↗
PubMed1993

Distinctive integrin expression in the newly forming epidermis during wound healing in humans.

The integrin receptor family plays a fundamental role in mediating cell attachment to a variety of extracellular matrix molecules. In normal human epidermis, the alpha 2 beta 1, alpha 3 beta 1, alpha 6 beta 4, and alpha v beta 5 integrin heterodimers are expressed and appear largely confined to the basal cell layer. In the present study, beta 1, beta 4, and alpha v integrin expression in the epidermis during wound healing in humans was examined. Punch biopsies were performed on healthy volunteers. At daily intervals up to day 8, and at days 11, 14, 21, and 28, the wound site was surgically removed. Using immunofluorescence microscopy, several modifications of the integrin expression pattern were observed on migrating keratinocytes during the re-epithelialization phase of the wound-healing process: i) alpha v expression was strongly enhanced and polarized at the basal pole of basal keratinocytes; ii) among the beta 1 integrins, alpha 3 beta 1 was overexpressed and distributed over the entire basal keratinocyte membrane and a weak alpha 5 beta 1 reactivity became evident; and iii) alpha 6 beta 4 was detected as a linear staining along the newly forming dermal-epidermal junction. Moreover, both during the re-epithelialization phase and during the first 2 weeks after wound closure, alpha 3, alpha 6, alpha v, beta 1, and beta 4 were no longer confined to the basal layer, as in normal epidermis, but were also found on several suprabasal cell layers. These results suggest that alpha v beta 5, alpha 3 beta 1, and alpha 5 beta 1 may be the main integrin receptors mediating keratinocyte spreading and migration over the provisional matrix of the wound bed.

Adult↗
PubMed1993

[The clinical and echocardiographic parameters at rest and during mental arithmetic stress in preadolescent subjects with a hypertensive parent].

Previous studies have showed that a genetic predisposition and/or a family history of essential hypertension may play a significant role in the development of cardiovascular changes in borderline hypertensive patients. Moreover, mental stress has been identified as contributing to the development of cardiovascular disease. The aim of this study was to compare the possible changes in blood pressure and Doppler echocardiographic parameters in resting and during mental arithmetic stress in 21 children with a hypertensive parent (Group I) and 21 age-matched children with normotensive parents (Group II), similar for body mass index, alimentary and life habits, and not differing in resting blood pressure, heart rate and Doppler echocardiographic parameters. Mass index was slightly but not significantly high in Group I with respect to controls. During mental stress only in the children with a family history of hypertension there was a significant increase (p < 0.02) in systolic blood pressure. A positive relation between the increase in systolic blood pressure and end-diastolic thickness of interventricular septum and posterior wall was observed in the same group. In addition a close relation (p < 0.05) between mass index and end-systolic left ventricular stress at rest was evidenced, whereas a negative relation (p < 0.03) between the increase in systolic blood pressure on one side and the early peak diastolic filling velocity (Vmax E) and the ratio of early to atrial peak diastolic filling velocity (Vmax E/Vmax A), on the other side, were found.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Serological screening for herpes simplex virus during pregnancy.

620 pregnant women living in the Province of Padua were submitted to serological screening for Herpes simplex virus antibody activity. A prevalence of 82.26% was found in the population; the Authors discuss the significance of the findings with special regard to relevant obstetric questions.

Adolescent↗
PubMed1993

Clinical experience in gynaecological cancer management. D) Ovarian tumors--non-epithelial: report from the Gynaecological Institute of Padua University.

All the non-epithelial ovarian tumors observed from 1963 to 1991 in the Gynaecologic and Obstetric Institute of Padua University (I clinic Padova, II clinic Verona) are evaluated in order to outline the value of some risk factors: Post-Surgical FIGO stage, histotype and treatments. Sex-cord stromal tumors, germ cell tumors, sarcomas and gonadoblastomas are analyzed separately because of their different epidemiology and biology. The most important risk factor for prognosis is certainly the tumor stage at the first diagnosis.

Adolescent↗
PubMed1993

Endometrial cancer treatment today.

The Authors stress the role of surgery in the clinical management of endometrial cancer. The half Century case-series of Padua Gynaecologic Institute is considered.

Combined Modality Therapy↗
PubMed1992

Prolonged bleeding time in patients with lupus anticoagulant.

Platelet adhesion to collagen under flow conditions was studied in 18 patients with lupus anticoagulant, seven of which showed a prolonged bleeding time in the presence of a normal platelet count. The effect of patient plasma, IgG and purified anticardiolipin antibodies on platelet adhesion was also examined. We found a significant reduction of platelet adhesion in patients with lupus anticoagulant, which was more evident in patients with prolonged bleeding time. This platelet adhesion defect could be attributed to a plasma factor. In fact, patients' platelets regained normal adhesion when mixed with normal plasma, whereas controls' platelets showed abnormal adhesion in the presence of patient plasma. A causative role of antiphospholipid antibodies was demonstrated in experiments using purified immunoglobulins and anticardiolipin antibodies.

Adult↗