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Biomedical subjects

A Giordano

Publications and source records attributed to A Giordano.

At least 37 records · Page 2Linked to original sources
PubMed2005

tBid induces alterations of mitochondrial fatty acid oxidation flux by malonyl-CoA-independent inhibition of carnitine palmitoyltransferase-1.

Recent studies suggest a close relationship between cell metabolism and apoptosis. We have evaluated changes in lipid metabolism on permeabilized hepatocytes treated with truncated Bid (tBid) in the presence of caspase inhibitors and exogenous cytochrome c. The measurement of beta-oxidation flux by labeled palmitate demonstrates that tBid inhibits beta-oxidation, thereby resulting in the accumulation of palmitoyl-coenzyme A (CoA) and depletion of acetyl-carnitine and acylcarnitines, which is pathognomonic for inhibition of carnitine palmitoyltransferase-1 (CPT-1). We also show that tBid decreases CPT-1 activity by a mechanism independent of both malonyl-CoA, the key inhibitory molecule of CPT-1, and Bak and/or Bax, but dependent on cardiolipin decrease. Overexpression of Bcl-2, which is able to interact with CPT-1, counteracts the effects exerted by tBid on beta-oxidation. The unexpected role of tBid in the regulation of lipid beta-oxidation suggests a model in which tBid-induced metabolic decline leads to the accumulation of toxic lipid metabolites such as palmitoyl-CoA, which might become participants in the apoptotic pathway.

BH3 Interacting Domain Death Agonist Protein↗
PubMed2005

Targeting HER2 as a therapeutic strategy for breast cancer: a paradigmatic shift of drug development in oncology.

Targeted therapies are causing a dramatic change in cancer drug development. Trastuzumab, a humanized recombinant monoclonal antibody that recognizes the extracellular domain of HER2 trans-membrane protein, is among the first target-specific drugs that have been licensed for clinical use and its development represents a model of integration of new agents with classical treatment strategies. In preclinical models, trastuzumab has demonstrated a marked antiproliferative effect and a synergistic action with several chemotherapeutic agents. Monotherapy trials indicate that trastuzumab is active as a single agent in HER2 positive patients, is well tolerated, and is associated with preservation of quality of life (QoL). Furthermore, as first line therapy for metastatic breast cancer overexpressing HER2 receptor, the addition of trastuzumab to taxane-based chemotherapy significantly increased rate of objective response, time to disease progression and survival when compared with chemotherapy alone. Trastuzumab has shown important activity when used with many chemotherapeutic agents such as platinum salts, gemcitabine, vinorelbine and capecitabine and liposomal anthracyclines. Various trials are now ongoing to optimize the use of trastuzumab and to investigate its role in the adjuvant and in the neo-adjuvant setting.

Animals↗
PubMed2005

The regulation of ER-alpha transcription by pRb2/p130 in breast cancer.

Breast carcinoma is the most common form of neoplasia in women of the Western world, and the mortality from this disease in women is second only to that of lung cancer, with a means incidence of 10%. Although, several studies have indicated that the development of this fairly heterogeneous disease depends on a great many environmental, socio-economic, hormonal and genetic factors, the pathogenesis of breast cancer remains poorly understood. ER-alpha (estrogen-receptor alpha) and its ligand (17beta-estradiol) play a crucial role in normal breast development and have also been linked to mammary carcinogenesis and clinical outcome in breast cancer patients. The estrogen signaling regulates the growth of some breast tumors, and antiestrogen therapies can effectively block this growth signaling resulting in tumor suppression. However, most tumors eventually develop antiestrogen resistance, and antiestrogen are mostly ineffective in patience with advanced disease. Although several studies have been proposed that epigenetic events could be involved in ER-alpha silencing the mechanisms regulating ER-alpha transcription are poorly understood. Our studies suggested that pRb2/p130-complexes bind to the ER-alpha promoter and could be involved in the transcriptional regulation of the ER-alpha gene by altering chromatin structure and DNA methylation pattern.

Breast Neoplasms↗
PubMed2005

Effect of home-based telecardiology on chronic heart failure: costs and outcomes.

Chronic heart failure (CHF) remains a common cause of disability. We have investigated the use of home-based telecardiology (HBT) in CHF patients. Four hundred and twenty-six patients were enrolled in the study: 230 in the HBT group and 196 in the usual-care group. HBT consisted of trans-telephonic follow-up and electrocardiogram (ECG) monitoring, followed by visits from the paramedical and medical team. A one-lead ECG recording was transmitted to a receiving station, where a nurse was available for reporting and interactive teleconsultation. The patient could call the centre when assistance was required (tele-assistance), while the team could call the patient for scheduled appointments (telemonitoring). The one-year clinical outcomes showed that there was a significant reduction in rehospitalizations in the HBT group compared with the usual-care group (24% versus 34%, respectively). There was an increase in quality of life in the HBT group (mean Minnesota Living Questionnaire scores 29 and 23.5, respectively). The total costs were lower in the HBT group (107,494 and 140,874, respectively). The results suggest that a telecardiology service can detect and prevent clinical instability, reduce rehospitalization and lower the cost of managing CHF patients.

Cardiac Output, Low↗
PubMed2005

Telecardiology: one-lead electrocardiogram monitoring and nurse triage in chronic heart failure.

We investigated a home-based intervention based on telecardiology in patients with chronic heart failure (CHF). Two hundred and thirty CHF patients, aged 59 years (SD 9), in stable condition and with optimized therapy were enrolled. The programme consisted of trans-telephonic follow-up and electrocardiogram (ECG) monitoring followed by visits from a paramedical and medical team. The patient could call the centre when required (tele-assistance), while the team could call the patient at prescheduled times (telemonitoring). During the first 12 months, there were 3767 calls (873 ad hoc and 2894 scheduled calls). There were 648 events, including 126 episodes of asymptomatic hypotension and 168 episodes which were not due to cardiological symptoms. No actions were taken by the nurse after 2417 calls (64%). A change in therapy was suggested after 418 calls, hospital admission in 62 patients, further investigations for 243 patients and a consultation with the general practitioner in 41 patients. A total of 2303 one-lead ECG recordings were received (10 per patient); 126 recordings (6%) were diagnosed as pathological in comparison with the baseline one. The one-lead ECG recording was used for titration of beta-blockers in 79 patients (mean dosage 38 mg vs 42 mg, P<0.01). Home telenursing could be an important application of telemedicine and single-lead ECG recording seems to offer additional benefit in comparison with telephone follow-up alone.

Cardiac Output, Low↗
PubMed2005

Cardiac event recording yields more diagnoses than 24-hour Holter monitoring in patients with palpitations.

Palpitation is a common symptom that sometimes results from a substantial cardiac arrhythmia. We compared the diagnostic yield of trans-telephonic event monitors with those of Holter monitoring in patients with intermittent palpitations. In all, 310 patients were randomly assigned to receive an event recorder or 24-hour Holter monitoring. Event recorders were used for seven days or until two recordings were obtained while symptoms occurred. The main end-point was an electrocardiogram (ECG) recorded during symptoms. The patients with palpitation recorded the one-lead ECG trace and sent it to a telemedicine call centre, where a nurse responded. There were 119 symptomatic patients in the event recorder group and 74 in the Holter group. The total costs were 6019 for event recording and 9605 for Holter monitoring. The average costs were 51 per symptomatic patient detected by event recorder monitoring and 130 per symptomatic patient detected by Holter monitoring. More patients therefore received a clear diagnosis, and more quickly, when using event recording than with Holter monitoring. For this reason, event recorders are preferable to Holter monitors for patients with palpitations.

Arrhythmias, Cardiac↗
PubMed2004

Placental expression of substance P and vasoactive intestinal peptide: evidence for a local effect on hormone release.

The present study evaluated vasoactive intestinal peptide (VIP) and substance P (SP) mRNA expressions and the localization of both peptides in first- and third-trimester human placentas. VIP and SP mRNAs were detected by slot blot analysis in first- and third-trimester placental tissues. By immunohistochemistry both neuropeptides were localized in the trophoblast (syncytium and cytotrophoblastic cells) of the chorionic villi. Because little information is available on the role of VIP and/or SP on the secretion of placental hormones, we investigated the effect of these neuropeptides on human chorionic gonadotropin (hCG) and progesterone release from primary cultured human trophoblastic and JEG-3 cells. The addition of increasing doses of VIP resulted in a dose-dependent stimulation of hCG release from cultured human trophoblast and JEG-3 cells. Increasing doses of VIP also dose-dependently stimulated progesterone secretion from primary cultured trophoblastic cells at all time points evaluated and from JEG-3 cells only after 3 h. SP did not affect hCG and progesterone secretion either in cultured human trophoblast or in JEG-3 cells. In conclusion, the present study demonstrates that VIP and SP are mainly expressed in human trophoblasts, and that VIP modulates the in vitro secretion of hCG and progesterone, suggesting a different role in trophoblastic function of the two peptides.

Cells, Cultured↗
PubMed2004

The involvement of oxidative stress in bovine herpesvirus type 4-mediated apoptosis.

Bovine herpesvirus type 4 (BHV-4) belongs to the gamma-2-herpesviruses of the Gammaherpesvirinae subfamily. BHV-4 has a worldwide distribution and has been isolated in a variety of clinical diseases as well as from healthy cattle. In this report we demonstrate that BHV-4 induces apoptosis in MDBK cells. In the early phases of apoptosis, cells show an increase in the intracellular level of reactive oxygen species, which is indicative of oxidative stress. This precedes DNA fragmentation, a hallmark typical of apoptosis. Cells were protected from apoptosis only by certain antioxidants (butylated hydroxyanisole and ebselen), whereas N-acetylcysteine turned out to be ineffective. Antioxidants that protected cells from apoptosis prevented oxidative stress but failed to block virus growth. These observations suggest that oxidative stress may be a crucial event in the sequence leading to apoptotic cell death but apoptosis is not required for the multiplication of BHV-4.

Acetylcysteine↗
PubMed2004

Different TMS patterns of intracortical inhibition in early onset Alzheimer dementia and frontotemporal dementia.

OBJECTIVE: To investigate putative changes in cortical excitability of patients affected by early-onset mild dementia by means of transcranial magnetic stimulation (TMS) and to verify whether a peculiar neurophysiological profile may contribute to characterise Alzheimer's disease (AD) vs frontotemporal dementia (FTD). METHODS: Motor threshold and intracortical inhibition (ICI) and facilitation (ICF) after paired-pulse TMS (inter-stimulus intervals from 1 to 20 ms) were studied in two groups of early-onset demented patients with a neuropsychological profile suggestive of AD (n = 12) and FTD (n = 8). Twelve age-matched healthy subjects were considered as control group. In both patient groups, recordings were performed before and after a single oral dose of 4 mg galantamine. RESULTS: No significant difference in motor threshold was observed among the three studied groups. On the contrary, early-onset AD showed a significant reduction of ICI compared to control group, no changes were detected in FTD patients. No significant changes in ICF were found between both patient groups and healthy subjects. The acute administration of galantamine reversed the modified ICI in AD group. CONCLUSIONS: The differential pattern of ICI exhibited by early-onset AD vs FTD in the early stage of disease may represent a non-invasive, reproducible electrophysiological tool, which may contribute to early differential diagnosis and, possibly, to monitor therapeutic effectiveness. SIGNIFICANCE: The present results support the possibility that subtle, early modifications in intracortical circuitry features AD, but not FTD patients.

Aged↗
PubMed2004

Tissue distribution of a feline AGP related protein (fAGPrP) in cats with feline infectious peritonitis (FIP).

Feline alpha(1)-acid glycoprotein (fAGP) increases during feline infectious peritonitis (FIP). We have recently identified a 29 kDa protein that we named feline AGP-related protein (fAGPrP) due to its cross-reactivity with an anti-human AGP monoclonal antibody. In this work we describe the tissue distribution of fAGPrP during FIP, and its relationship with feline coronavirus (FCoV) and myeloid cells. Tissues from five control cats and from 15 cats with FIP were examined by immunohistochemistry using monoclonal antibodies against human AGP, FCoV and myeloid antigens. Diffuse fAGPrP positivity within the lesions, likely due to vascular plasma leakage, endothelial and epithelial lining were detectable. Compared to controls, fAGPrP-expressing cells often increased in number and were diffusely distributed in lymph nodes, as usually occurs for IgM-producing plasma cells during early immune responses. These findings did not depend on the presence of FCoVs or of myeloid cells, suggesting that fAGPrP is not directly involved in the pathogenesis of FIP.

Animals↗
PubMed2004

Changes in some acute phase protein and immunoglobulin concentrations in cats affected by feline infectious peritonitis or exposed to feline coronavirus infection.

The possible role of some acute phase proteins (APPs) and immunoglobulins in both the pathogenesis and diagnosis of feline infectious peritonitis (FIP) has been investigated. Serum protein electrophoresis and the concentration of haptoglobin (Hp), serum amyloid A (SAA), alpha(1)-acid glycoprotein (AGP), IgG and IgM were evaluated in cats exposed to feline coronavirus (FCoV) and in cats with FIP. The highest concentration of APPs was detected in affected cats, confirming the role of these proteins in supporting a clinical diagnosis of FIP. Repeated samplings from both FIP affected and FCoV-exposed cats showed that when FIP appeared in the group, all the cats had increased APP levels. This increase persisted only in cats that developed FIP (in spite of a decrease in alpha(2)-globulins) but it was only transient in FCoV-exposed cats, in which a long lasting increase in alpha(2)-globulins was observed. These results suggest that changes in the electrophoretic motility of APPs or APPs other than Hp, SAA and AGP might be involved in the pathogenesis of FIP or in protecting cats from the disease.

Acute-Phase Proteins↗
PubMed2004

Synthesis and characterisation of poly(2-hydroxyethyl methacrylate) polyelectrolyte complexes.

Copolymerisation of charged and neutral monomers is a well-known methodology to introduce charged moieties in a polymeric chain to obtain polyelectrolytes. New polyelectrolyte complexes have been synthesised by radical copolymerisation of neutral methacrylic monomer 2-hydroxyethyl methacrylate (HEMA) with cationic 2-methacryloyloxyethyltrimethyl ammonium chloride and anionic 2-acrylamido-2-methylpropane-sulphonic acid monomers in 10:1:1 and 10:1:2 stechiometric ratio. Chemical structure of the synthesised terpolymers was confirmed by FT-IR spectroscopy, moreover, X-ray photoelectron spectroscopy showed the presence of a cationic charge excess on the 10:1:2 terpolymer surface with respect to 10:1:1 terpolymer. Swelling studies for 10:1:2 terpolymers showed a high water content in the swollen state and a "smart behaviour" upon changes in external stimuli such as pH, while, 10:1:1 terpolymer presented the behaviour of a neutral polymer. Mechanical and differential scanning calorimetry analysis confirmed that terpolymer networks were stabilised by ionic co-operative interactions. Infact, the inclusion of oppositely ionic charges in the polymeric network of p(HEMA) represent a way to achieve higher elastic modulus as they stabilise the terpolymer networks. Cytotoxicity and cytocompatibility studies demonstrated that all materials were not toxic, moreover, the presence of a cationic charge excess on 10:1:2 terpolymer surface was able to promote fibroblast adhesion.

Absorption↗
PubMed2004

Endothelial dysfunction in young patients with rheumatoid arthritis and low disease activity.

BACKGROUND: Rheumatoid arthritis (RA) is associated with an increased risk of cardiovascular disease. Endothelial dysfunction represents the earliest stage of atherosclerosis. OBJECTIVE: To evaluate the influence of chronic inflammatory state on endothelial function in patients with RA by measuring endothelial reactivity in young patients with RA with low disease activity and without traditional cardiovascular risk factors. METHODS: Brachial flow mediated vasodilatation (FMV), assessed by non-invasive ultrasound, was evaluated in 32 young to middle aged patients with RA (age </=59 years), with DAS28 </=3.2 and without overt cardiovascular disease, and in 28 age and sex matched controls. RESULTS: Mean (SD) FMV was significantly lower in patients than in controls (3.2 (1.3)% v 5.7 (2.0)%; p<0.001), inversely related to low density lipoprotein cholesterol (r = -0.45, p<0.05) and C reactive protein (CRP), expressed as the value at the moment of ultrasound evaluation (r = -0.44, p<0.05), as the average of CRP levels evaluated at different times during the disease (r = -0.47, p<0.05), or as the average of >/=4 determinations multiplied by the disease duration (r = -0.40, p<0.05). In a multivariate regression model, a lower brachial flow mediated vasodilatation was independently predicted by low density lipoprotein cholesterol (beta = -0.40, p<0.05), average CRP levels multiplied by the disease duration (beta = -0.44, p<0.05), and brachial artery diameter (beta = -0.28, p<0.05). CONCLUSIONS: Young to middle aged patients with RA with low disease activity, free from cardiovascular risk factors and overt cardiovascular disease, have an altered endothelial reactivity that seems to be primarily related to the disease associated chronic inflammatory condition.

Adult↗
PubMed2004

Polyomaviruses and cancer--interplay between viral proteins and signal transduction pathways.

Polyomaviruses are highly suspected to be involved in the development of cancer. A strong correlation has been established between the activity of an early viral genome and the development of a transformed phenotype. Polyomavirus transforming antigens (T-antigens) are the major suspects in the process of deregulating cellular equilibrium. Multiple interactions between T-antigens and cellular regulatory proteins have been detected at different regulatory levels including signal transduction, gene expression, cell cycle progression, and possible DNA repair. In this context, we are reviewing the most recent experimental evidence which, in combination with more than thirty years of studies of polyomaviruses, could help us understand whether and how viral infection contributes to the development of malignant transformation.

Animals↗
PubMed2003

Interference of bovine herpesvirus 1 (BHV-1) in sorbitol-Induced apoptosis.

In order to determine the ability of bovine herpesvirus type 1 (BHV-1) to suppress apoptosis, we examined the effects of BHV-1 infection on sorbitol-induced apoptosis on Madin-Darby bovine kidney (MDBK) cells. BHV-1 suppresses sorbitol-induced apoptosis in a manner similar to that of herpes simplex virus type 1 (HSV-1), indicating that BHV-1 has one or more anti-apoptotic genes. To elucidate the molecular mechanisms of apoptosis, expression of some genes encoding apoptosis-inhibiting and -promoting factors were analyzed on BHV-1 infected cells during the process of sorbitol-induced apoptosis. Our results revealed that the expression of bcl-2 and bcl-x(L) decreased after 5 and 3 h p.i., respectively; while bax and procaspase-3 expression increased with respect to control as a function of p.i. times and at 7 h p.i. they were not observed. We further show that the expression of p53 gene was also enhanced, suggesting that this apoptotic mechanism is p53 dependent. From these results, we propose that BHV-1 has one or more genes encoding apoptosis-inhibiting factors which interfere with the involvement of bcl-2 gene family members and apoptotic pathway, depending upon caspase-3, triggered by sorbitol.

Animals↗
PubMed2003

EGF-responsive rat neural stem cells: molecular follow-up of neuron and astrocyte differentiation in vitro.

Neural stem cells (NSCs) could be very useful for the "cell therapy" treatment of neurological disorders. For this reason basic studies aiming to well characterize the biology of NSCs are of great interest. We carried out a molecular and immunocytochemical analysis of EGF-responsive NSCs obtained from rat pups. After the initial growth of NSCs as floating neurospheres in EGF-containing medium, cells were plated on poly-L-ornithine-coated dishes either in the presence or absence of EGF. We followed cell differentiation and apoptosis for 21 days in vitro and analyzed the expression levels of some genes having a major role in these processes, such as pRB, pRB2/p130, p27, and p53. We observed that EGF impairs neuronal differentiation. Furthermore, in the absence of mitogens, apoptosis, which appeared to proceed through the "p53 network," was significantly lower than in the presence of EGF. The cyclin kinase inhibitor p27, while important for cell cycle exit, seemed dispensable for cell survival and differentiation.

Animals↗