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Biomedical subjects

P Biagi

Publications and source records attributed to P Biagi.

At least 19 recordsLinked to original sources
PubMed2005

Antioxidant effectiveness of organically and non-organically grown red oranges in cell culture systems.

BACKGROUND: Consumers consider plant food products from organic origin healthier than the corresponding conventional plant foods. Clear experimental evidence supporting this assumption is still lacking. AIM OF THE STUDY: To determine if the organic red oranges have a higher phyto-chemical content (i. e., phenolics, anthocyanins and ascorbic acid), total antioxidant activity and in vitro bioactivity, in terms of protective effect against oxidative damage at cellular level, than nonorganic red oranges. METHODS: Total phenolics were measured using the Folin Ciocalteau assay, while total anthocyanins and ascorbic acid levels were determined by spectrophotometric and HPLC analysis, respectively. In addition, the total antioxidant activity of red orange extracts was measured by the ABTS(*+) test. The ability of red orange extracts to counteract conjugated diene containing lipids and free radical production in cultured rat cardiomyocytes and differentiated Caco-2 cells, respectively, was assessed. RESULTS: Organic oranges had significantly higher total phenolics, total anthocyanins and ascorbic acid levels than the corresponding non-organic oranges (all p < 0.05). Moreover, the organic orange extracts had a higher total antioxidant activity than non-organic orange extracts (p < 0.05). In addition, our results indicate that red oranges have a strong capacity of inhibiting the production of conjugated diene containing lipids and free radicals in rat cardiomyocytes and differentiated Caco-2 cells, respectively. Statistically higher levels of antioxidant activity in both cell models were found in organically grown oranges as compared to those produced by integrated agriculture practice. CONCLUSIONS: Our results clearly show that organic red oranges have a higher phytochemical content (i. e., phenolics, anthocyanins and ascorbic acid), total antioxidant activity and bioactivity than integrated red oranges. Further studies are needed to confirm whether the organic agriculture practice is likely to increase the antioxidant activity of other varieties of fruits and vegetables.

Agriculture↗
PubMed2001

Is increased arachidonic acid release a cause or a consequence of replicative senescence?

Arachidonic acid (AA) has been related to both stimulation and inhibition of cellular proliferation. During replicative senescence of human fibroblasts, increased levels of AA have been thought to play a causal role in the limited proliferative capacity of the cells. To clarify the role of AA in the proliferation of normal fibroblasts and in cellular senescence, we examined uptake from and release of AA into the culture media and its effects on DNA synthesis. Our results indicate that some aspects of AA metabolism in normal human fibroblasts aged in culture are significantly different in comparison to early passage cells. Particularly, AA release following different mitogenic stimulation is higher in senescent than in young cells. Notwithstanding this significant difference, AA, at the concentration used, has no inhibitory effect on fibroblast DNA synthesis. Moreover AA and prostaglandins are responsible for the proliferative block in neither senescent cells nor mediate ceramide inhibition of DNA synthesis. So our results suggest that the increasing AA release is not causal, but rather the result of in vitro aging.

Aging↗
PubMed2000

Dietary manipulation of delta-6-desaturase modifies phospholipid arachidonic acid levels and the urinary excretion of calcium and oxalate in the rat: insight in calcium lithogenesis.

An anomalous n-6 polyunsaturated fatty acid composition in plasma and erythrocyte membrane phospholipids, namely increased levels of arachidonic acid (AA), has been reported in calcium nephrolithiasis and has been proposed to play an important role in its pathogenesis. To confirm this, in rats we modified phospholipid AA levels by dietary manipulation of the delta-6-desaturase, the rate-limiting enzyme of the fatty acid biosynthetic pathway, and evaluated the effect on cellular and renal functions predisposing to lithogenesis. Increased AA levels led to conditions at risk for nephrolithiasis: higher oxalate flux and lower sodium cotransport in erythrocytes and a rise in urinary prostaglandin E2, calcium, sodium, and oxalate levels; reduced AA levels reversed these changes. In vitro, in human erythrocytes the incorporation of exogenous AA into membranes increased band 3 protein phosphorylation directly activating the Ser/Thr protein kinase CK1 and induced a parallel raise in band 3-mediated oxalate transport. These findings demonstrate the pivotal role of phospholipid AA in modulating erythrocyte and renal transport of calcium and oxalate.

Animals↗
PubMed2000

Takayasu's arteritis associated with Crohn's disease. Report of a case.

The authors report a rare case of Takayasu's arteritis with aortic arch and abdominal aorta involvement associated with Crohn's disease of the colon which both occurred in a young female patient. The coexistence of two immune mediated diseases in the same subject is unusual for they are generally considered to be independent of each other, however a hypothesis of their possible interrelationship is put forward.

Adult↗
PubMed2000

Seroprevalence of Helicobacter pylori infection in a group of hospitalized geriatric patients.

BACKGROUND: In recent years several epidemiological surveys have reported the association between Helicobacter Pylori (HP), chronic ischemic heart disease (CHD) and cerebrovascular disease (CVD). None involved the geriatric population in which these diseases are prevalent. METHODS: We investigated the HP seropositivity prevalence in a group of over 75-year-old subjects recruited among all patients consecutively admitted for various diseases in an Internal Medicine Department during a period of 9 months. INTERVENTION: We measured HP IgG antibodies employing a commercially available kit based on reverse flow chromatography highly feasible and simple to perform and we investigated all patients for past or present CHD/CVD. RESULTS: From our data, the prevalence of seropositivity to Hp does not differ from other wider age stratified studies; more in detail; in the over 90-year-old patients we found the same HP seropositivity prevalence as in younger group but were not able to confirm the progressive lowering or seroprevalence in extreme geriatric age. CONCLUSIONS: No clear correlation between HP seroprevalence and CHD and CVD was found, but a link with CHD seems possible for the determinant (age) is common to both conditions.

Aged↗
PubMed1999

The impairment of essential fatty acid metabolism as a key factor in doxorubicin-induced damage in cultured rat cardiomyocytes.

The clinical use of the antitumoral doxorubicin (DOX) is limited by its cardiotoxicity, which is mediated through different mechanisms. The membrane lipid peroxidation induced by DOX may cause disruption of the unsaturated fatty acyl chains; in the endoplasmic reticulum, containing the system catalyzing the desaturation/elongation of fatty acids, DOX could interfere with the metabolism of linoleic and alpha-linolenic acids. Using primary cultures of neonatal rat cardiomyocytes we demonstrated that the exposure to different concentrations of DOX (10(-5) and 10(-7) M) for 24 h caused an increase in the production of conjugated dienes, an impairment in the desaturation/elongation of essential fatty acids, and a reduction in the cellular content of highly unsaturated fatty acids. Conversely, 1 h exposure to 10(-5) M DOX was sufficient to induce alterations in the desaturation/elongation of linoleic and alpha-linolenic acids, but did not cause either formation of conjugated dienes or modification of the fatty acyl pattern. Therefore, DOX has a dual negative effect, depending on its concentration and on the time of exposure, one directed against the membrane highly unsaturated fatty acids, the other against the system which is required for the synthesis of these fatty acids themselves. These two effects synergically act in causing heart cell damage.

Animals↗
PubMed1999

A case of neurofibromatosis type 1 with an aldosterone-producing adenoma of the adrenal.

Neurofibromatosis type 1 is a phacomatosis. Neurofibromas are the most common tumours associated with the disease, and along with other tumours, make neurofibromatosis type 1 the most common tumour predisposing syndrome in humans. Hypertension may be coincidental, but at least two specific neurofibromatosis related causes must be considered, namely neurofibromatous involvement of the renal artery and pheochromocytoma. We have described the first known case of a patient with neurofibromatosis type 1 who developed hypertension due to an aldosterone-producing adenoma of the adrenal. The question of whether this association was coincidental or due to the tumour predisposition of neurofibromatosis type 1 was debated.

Adenoma↗
PubMed1999

[Tularemia: considerations on a new case in the Monte Amiata].

One sporadic case of tularemia induced by direct contact with an infected hare is described. Human epidemiological data of the last ten years in Tuscany, emphasize that this infection, although at low incidence, shows the presence and persistence of Francisella tularensis in the animals and the ensuing transmission to humans so that it continues to be responsible for significant morbididy in "at risk" territories. Difficulties in the differential diagnosis, above all for glandular and pharyngeal forms, are reviewed.

Humans↗
PubMed1996

gamma-Linolenic acid supplementation can affect cancer cell proliferation via modification of fatty acid composition.

We examined the effect of gamma-linolenic acid (GLA) supplementation on the growth and fatty acid composition of three human tumor cell lines (the neuroblastoma CHP-212, the tubal carcinoma TG, and the colon carcinoma SW-620), in order to evaluate the relationship between GLA-induced tumor cell death and the distribution of fatty acids in tumor cells. At the highest GLA concentrations (10 and 20 micrograms/ml), the DNA synthesis was completely abolished; at 5 micrograms/ml GLA only SW-620 cells did not proliferate, while CHP-212 and TG cells showed a residual [3H]-thymidine incorporation. GLA levels were very low in cells grown in control medium; GLA supplementation caused a significant incorporation of GLA itself in all the cell lines at each concentration. In TG and CHP-212 cells, GLA was metabolized, although to a different extent, to dihomo-gamma linolenic acid and arachidonic acid. SW-620 cells neither elongated nor desaturated the incorporated GLA. The highest cytostatic effect was reached when GLA was not transformed into its metabolites, suggesting that the GLA toxicity to tumor cells is not dependent on metabolites but is due to GLA itself.

Cell Division↗
PubMed1995

[Digoxin-like immunoreactive factors. Review of the literature].

It is confirmed by several studies that in normal subjects a substance recognized by antibodies anti digoxin exists. Such a substance can be found at increased concentration in pregnant women, neonates, in liver or kidney diseases. A limited increase in concentration has been also registered in patients with essential hypertension and in normotensive patients with a family history of hypertension. Serum or urines rich in such a substance show an increased capacity of inhibiting in vitro the sodium-potassium pump and therefore in reducing also in vivo the capacity of reabsorption of sodium and with it, of water. The investigators interest for this substance has two main reasons: 1) the interference that such a substance has in dosages of digitalis in therapeutic monitorizing; 2) the possibility that such a substance has an important physiological role in hydroelectrolytic metabolism.

Adult↗
PubMed1994

Dynamic of alpha-1-adrenoceptor mediated degradation of membrane phospholipids in cultured rat cardiomyocytes.

In many cell types, agonists can stimulate both phosphoinositide (PtdIns) and phosphatidylcholine (PC) hydrolysis by activating specific phospholipases. Using cultures of neonatal rat cardiomyocytes we have verified the existence of an alpha 1-adrenoceptor mediated hydrolysis of PtdIns and PC. PtdIns breakdown, evaluated as inositol phosphate production, occurred in the early phase of cell stimulation, while PC hydrolysis, evaluated as choline metabolite production, was evidenced at longer stimulation times. The appearance of a delayed peak of choline phosphate and the invariance of free choline in the intracellular water phase strongly suggest the involvement of a specific PC-phospholipase C, generating choline phosphate and diacylglycerol, the activator of protein kinase C. Since it is plausible that various metabolites of signal-induced degradation of membrane phospholipids may take part in long term physiological responses, PC breakdown could be involved in cellular mechanisms that require prolonged protein kinase C activation.

Animals↗
PubMed1994

Lingual thyroid and hypothyroidism. Report of a case in a middle aged woman.

There are approximately 400 reported cases of lingual thyroid (LT) with a clear cut prevalence in paediatric age. These glands are probably quantitatively deficient and function at marginal levels. Thyro-stimulating hormone (TSH) causes hypertrophy producing local symptoms and in younger patients may induce dangerous obstruction. The presumptive diagnosis is usually made by indirect laryngoscopy and thyroscintigraphy. The authors describe a case of LT in a middle aged patient in whom the anomaly remained undiscovered, being without local symptoms, and permitting a normal life. The discovery was made possible by the development in the last four years of a progressive, frank hypothyroidism, probably induced by silent thyroiditis into the ectopic gland.

Adult↗
PubMed1994

Effect of cholesterol-5 alpha,6 alpha-epoxide supplementation to cultured cardiomyocytes.

In order to evaluate the effect of one of the main oxysterols derived from cholesterol oxidation, cholesterol-5 alpha,6 alpha-epoxide (epox), on cardiac cells, we have supplemented the culture medium of neonatal rat cardiomyocytes with scalar concentrations of epox (0.1-100 microM). While 0.1 microM epox supplementation was ineffective, epox supplementation in the range 1-100 microM determined a reduction in cellular protein level, without affecting cell viability, and a dose-dependent epox incorporation into cardiomyocyte lipids. Furthermore, in the same concentration range of epox supplementation, a gas chromatographic peak unambiguously identified by gas chromatography-mass spectrometry as cholestane-3 beta,5 alpha,6 beta-triol, an hydrolytic metabolite of epox, was detected. The mechanism of cytotoxicity of epox to cardiomyocytes could be due to the insertion of epox itself into cellular lipids, and to its metabolization to the more toxic triol.

Animals↗
PubMed1993

[Primary empty sella syndrome. Report of 6 cases].

The extension of the suprasellar subarachnoid space through an incompetent diaphragma sellae into the sella turcica is defined as empty sella syndrome (ESS). The primary form arises in the absence of previous pituitary surgery or irradiation. Predominance of obese, middle aged, often multiparous women are generally observed; clinically headaches and slight endocrine alterations are frequent but not characteristic symptoms. Rarely liquor rhinorrhea or visual campimetric defects may occur. The authors report six cases observed in their Departments of Internal Medicine during the last two years; they discuss the aspecific symptoms of presentation and the associated pathologic conditions. Standard skull X rays were negative in half the cases showing the overall poor sensitivity of this examination in detecting ESS. According to the literature no evident abnormality of hypophyseal basal hormone levels was found. Diagnosis was done by high resolution TC or MR which now must be preferred to pneumoencephalography (PEG). Three patients had peculiar pathologic conditions associated with ESS: a very high suspicion of partial insipidus diabetes was made in a man with hypo-osmolar polyuria; one patient without related humoral symptoms had a duodenal carcinoid endoscopically removed and in another primary ESS was associated with Hashimoto thyroiditis. These last two pathologies were never related before associated to primary ESS. The authors conclude that primary ESS is most often a diagnosis made by serendipity, lacking specific signs and or symptoms, whenever an imaging technique (TC or MR) is employed for detecting an unrelated endocranic pathology or the content of an enlarged sella turcica.

Aged↗
PubMed1991

Reduced neutrophil superoxide generation and plasma lipoperoxide levels in pigs fed with cod liver oil.

Circulating neutrophils, isolated from pigs fed for 8 weeks with a diet supplemented with CLO, had an accentuated n-3 fatty acid incorporation into the plasma membrane, as evidenced by an approximately four-fold greater n-3/n-6 ratio as compared with the control diet group. Moreover, the neutrophils of the CLO fed pigs produced less superoxide when stimulated with PMA or f-MLP, as well as showing a more prolonged latency period before O2(-)-generation. In the plasma of pigs fed with CLO there were higher levels of thiobarbituric reactive material and lipofuscin, while the content of GSSG was similar in both dietary groups. The results of this study indicate that dietary supplementation with CLO reduces the activation of circulating neutrophils and favours the presence in the plasma of lipoperoxides.

Animals↗
PubMed1990

[Enlargement of the lymph nodes of the hilus hepatis: a further ultrasonographic sign of acute viral hepatitis].

Enlarged hilar lymph nodes are usually reported as the most frequent US finding in acute viral hepatitis. The authors compared this finding with other pathologic conditions--i.e., asymptomatic cholelithiasis and acute cholecystitis--and with gallbladder wall thickening, which is also observed in acute hepatitis. From their results, they drew the following conclusions: a) lymph node enlargement at the hepatic hilum was a very frequent finding (11/15) at US in the patients with acute viral hepatitis; b) its occurrence was statistically more frequent than in both cholelithiasis and cholecystitis; c) gallbladder wall thickening was found in 53.3% of the patients with acute hepatitis; d) lymph node enlargement and gallbladder wall thickening were not related. The authors suppose enlarged lymph nodes to be suggestive of hepatic damage in a pattern of immunological hyperactivity rather than the result of inflammatory gallbladder conditions during acute hepatitis. Since only 2 cases could be followed, the authors cannot discuss the prognostic significance of enlarged lymph nodes after cytolytic enzymatic signs of viral hepatitis have disappeared.

Acute Disease↗
PubMed1990

[Abdominal lymph nodes: the echographic evaluation criteria].

US patterns of abdominal lymph nodes were investigated in patients with neoplastic and non-neoplastic diseases, and in randomly-chosen subjects with no evidence of any pathologic condition. Major longitudinal diameter (DMax) was statistically evaluated, together with minor transverse diameter (DMin), roundness index (RI), and structural index (IS)-i.e., the presence of a central hyperechoic line (as the US sign of normal lymph node architecture). DMax proved to be useless for distinguishing between groups. The presence of a central hyperechoic line was the most useful parameter, although the extant 3 (DMin, RI, IS) were also useful for distinguishing between groups. By correlating each numerical parameter with the hyperechoic line sign an even better discrimination was obtained. Thus, it can be assumed that only a combined and comprehensive evaluation of the above parameters makes the best criterion to differentiate between neoplastic and non-neoplastic abdominal lymph nodes.

Abdomen↗