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Biomedical subjects

G Ghirlanda

Publications and source records attributed to G Ghirlanda.

At least 19 recordsLinked to original sources
PubMed2006

Slight association between type 1 diabetes and "ff" VDR FokI genotype in patients from the Italian Lazio Region. Lack of association with diabetes complications.

BACKGROUND: Vitamin D receptor (VDR) mediates the effects of vitamin D. Our paper evaluates the FokI and BsmI VDR genotypes in 246 Caucasian (Italian from Lazio Region) T1DM patients compared with 246 Caucasian healthy controls, sharing age and gender and regional provenience with the patients. In addition, T1DM patients without complications were compared with those carrying three complications. METHODS: Genotyping has been obtained by RFLP-PCR technique. RESULTS: A slight significant association of T1DM with FokI homozygous "f" genotype was observed. No association was observed with the presence of multiple complications by a multivariate analysis. CONCLUSION: T1DM patients showed slightly increased prevalence of "ff" VDR genotype.

Adult↗
PubMed2005

Hypercreatininemia and hyperglycemia: diabetic nephropathy or "inverted peritoneal auto-dialysis"?

We describe a case of 51-year-old male with fever, abdominal pain and inguino-scrotal hernia. Laboratory examination revealed hypercreatininemia and hyperglycemia, firstly interpreted as diabetic nephropathy. US and CT scan showed a hernia of the bladder into the scrotum. Surgery revealed multiple bladder perforations with peritoneal diffusion of urine. So, hypercreatininemia was caused by peritoneal reabsorption of urea and creatinine, a condition that may be described as "inverted peritoneal auto-dialysis". Surgical reposition and repairment of the bladder led to rapid normalization of serum urea and creatinine. Discharged diagnosis was intraperitoneal rupture of inguino-scrotal hernia of the bladder in patient with recent onset of diabetes mellitus.

Creatinine↗
PubMed2004

Long-term taurine supplementation reduces mortality rate in streptozotocin-induced diabetic rats.

Oxidative stress is implicated in the pathogenesis of diabetes mellitus. Taurine and vitamin E+selenium supplementation has some benefits in experimental models of diabetes mellitus. This study evaluates whether taurine and vitamin E+selenium supplementations reduce a hard end-point such as mortality due to diabetes. Streptozotocin-induced diabetic rats were fed with standard diet or taurine (5%, w/w) or vitamin E (500 UI/Kg)+selenium (8 mg/Kg) enriched diets. Taurine significantly decreased mortality rate (p < 0.04), while vitamin E failed to increase survival. In the late phase of the disease, taurine significantly decreased glycaemia, being vitamin E ineffective. No correlation between glycaemia and survival was found. None of supplementations modified body weight. Thus, only taurine decreases the mortality rate and glycaemia. These results encourage new research in the field, since classical hypoglycaemic agents are unable to decrease mortality in diabetic patients.

Animals↗
PubMed2002

Chronic taurine supplementation ameliorates oxidative stress and Na+ K+ ATPase impairment in the retina of diabetic rats.

This study evaluates the effect of 4 months supplementation with 2% and 5% taurine (w/w) on the retina of diabetic rats. In non-diabetic rats, taurine does not modify glycemia, body weight, retinal conjugated dienes (CD), lipid hydroperoxide (LP), and Na(+)K(+)ATPase activity. In diabetic rat, at 2, 4, 8, 16 weeks following the onset of diabetes, retinal CD and LP are significantly and progressively increased, while pump activity is gradually and significantly reduced. In taurine supplemented diabetic rats, glycemia is not affected but lipid peroxidation is significantly decreased. Finally, taurine preserves ATPase activity being 5% more effective than 2% taurine. We conclude that taurine supplementation ameliorates biochemical retinal abnormalities caused by diabetes, thereby suggesting that taurine may have a role in the prevention of retinal changes in diabetes.

Animals↗
PubMed2002

Lower limb nerve impairment in diabetic patients: multiperspective assessment.

To assess the relationship between patient's perception of his own inferior limbs symptom and function and the clinical-neurophysiological assessment in patients affected by insulin-dependent diabetes mellitus (IDDM). We studied 50 consecutive outpatients affected by IDDM (23 men, 27 women). We used validated measurements clinical [Semmes-Weinstein (SW), vibration perception threshold (VPT), muscle strength, osteotendineous reflexes, etc.], neurophysiological (sural, peroneal nerves), metabolic and patient-oriented [North American Spine Society (NASS) questionnaire]. Patient-oriented scores were significantly related with neurophysiological findings of the inferior limbs. Our data suggest that electrodiagnostic tests are useful to assess the severity of the diabetic polyneuropathy not only because they provide a biological measurement of the nerve function but also because they appeared related to the patient's quality of life related to the peripheral nerve involvement.

Adult↗
PubMed2001

D(n)-symmetrical tertiary templates for the design of tubular proteins.

Antiparallel helical bundles are found in a wide range of proteins. Often, four-helical bundles form tube-like structures, with binding sites for substrates or cofactors near their centers. For example, a transmembrane four-helical bundle in cytochrome bc(1) binds a pair of porphyrins in an elongated central cavity running down the center of the structure. Antiparallel helical barrels with larger diameters are found in the crystal structures of TolC and DSD, which form antiparallel 12-helical and six-helical bundles, respectively. The backbone geometries of the helical bundles of cytochrome bc(1), TolC, and DSD are well described using a simple D(n)-symmetrical model with only eight adjustable parameters. This parameterization provides an excellent starting point for construction of minimal models of these proteins as well as the de novo design of proteins with novel functions.

Bacterial Outer Membrane Proteins↗
PubMed2001

Stabilization of coiled-coil peptide domains by introduction of trifluoroleucine.

Substitution of leucine residues by 5,5,5-trifluoroleucine at the d-positions of the leucine zipper peptide GCN4-p1d increases the thermal stability of the coiled-coil structure. The midpoint thermal unfolding temperature of the fluorinated peptide is elevated by 13 degrees C at 30 microM peptide concentration. The modified peptide is more resistant to chaotropic denaturants, and the free energy of folding of the fluorinated peptide is 0.5-1.2 kcal/mol larger than that of the hydrogenated form. A similarly fluorinated form of the DNA-binding peptide GCN4-bZip binds to target DNA sequences with affinity and specificity identical to those of the hydrogenated form, while demonstrating enhanced thermal stability. Molecular dynamics simulation on the fluorinated GCN4-p1d peptide using the Surface Generalized Born implicit solvation model revealed that the coiled-coil binding energy is 55% more favorable upon fluorination. These results suggest that fluorination of hydrophobic substructures in peptides and proteins may provide new means of increasing protein stability, enhancing protein assembly, and strengthening receptor-ligand interactions.

Amino Acid Sequence↗
PubMed2001

Design of three-dimensional domain-swapped dimers and fibrous oligomers.

Three-dimensional (3D) domain-swapped proteins are intermolecularly folded analogs of monomeric proteins; both are stabilized by the identical interactions, but the individual domains interact intramolecularly in monomeric proteins, whereas they form intermolecular interactions in 3D domain-swapped structures. The structures and conditions of formation of several domain-swapped dimers and trimers are known, but the formation of higher order 3D domain-swapped oligomers has been less thoroughly studied. Here we contrast the structural consequences of domain swapping from two designed three-helix bundles: one with an up-down-up topology, and the other with an up-down-down topology. The up-down-up topology gives rise to a domain-swapped dimer whose structure has been determined to 1.5 A resolution by x-ray crystallography. In contrast, the domain-swapped protein with an up-down-down topology forms fibrils as shown by electron microscopy and dynamic light scattering. This demonstrates that design principles can predict the oligomeric state of 3D domain-swapped molecules, which should aid in the design of domain-swapped proteins and biomaterials.

Dimerization↗
PubMed2001

Health-related quality of life in type 1 diabetic patients and influence of peripheral nerve involvement.

We examined the relationships between diabetic peripheral nerve involvement and patients' own perception of quality of life in a multidimensional study based on outcome research recommendations. The study enrolled 50 consecutive outpatients with type 1 diabetes mellitus (23 men, 27 women; mean age, 40.1 years). The patients were evaluated with validated clinical tests (e. g. Semmes-Weinstein, vibration perception threshold, muscle strength), neurophysiological tests (sural, peroneal and ulnar nerves) and patient-oriented (SF-36 and NASS) questionnaires. Patient-oriented physical scores were significantly related with: (1) neurophysiological findings of the lower limbs; (2) conventional measurements of sensitivity. Conversely, patient-oriented mental scores were not related with these findings. The patient-oriented questionnaires provided an important perspective of the severity of the disease, often closely related with the biological parameters. They offered new interpretations to conventional biological measurements. In particular, the peripheral nerve picture was strictly related to the physical aspects of the patients' quality of life, and not with the mental aspects.

Adult↗
PubMed2001

Autoantibodies and endothelial dysfunction in well-controlled, uncomplicated insulin-dependent diabetes mellitus patients.

Patients with insulin-dependent diabetes mellitus (IDDM) are well known to be at high risk of vascular disease, and dysfunction of vascular endothelium is considered as an early step in the development of diabetic complications. Because of the involvement of autoimmunity in the pathogenesis of IDDM, our aim was to assess, in 45 IDDM patients without clinically evident vascular complications, whether early signs of endothelial cell dysfunction were correlated to alterations of the immune system. IDDM patients were characterized by significantly increased serum levels of C-reactive protein, of polymorphonuclear cells-derived elastase, of endothelin-1 (ET-1) and of thrombomodulin, while plasma concentrations of fibronectin (FNT) were significantly decreased, with a statistically significant inverse correlation between ET-1 and FNT values. The presence of circulating immune complexes (CIC) was investigated in 36 out of our 45 IDDM patients, and values above the cut-off were found in 17 (47.2%) of them. One-third of all patients showed values above the cut-off for IgG-aCL. In IDDM patients, at variance from the control group, the levels of ET-1 were directly correlated to those of von Willebrand factor, of anticardiolipin beta(2)-GPI and of CIC, with an inverse correlation with plasma FNT. An association between antiphospholipid antibodies and endothelial dysfunction and/or activation is therefore suggested, pointing to a synergism, in the early phases of IDDM vascular disease, between generation of autoantibodies and endothelial activation.

Adult↗
PubMed2001

Markedly reduced insulin-like growth factor-1 in the acute phase of myocardial infarction.

OBJECTIVES: We investigated whether insulin-like growth factor-1 (IGF-1) is reduced in the early phase of acute myocardial infarction (AMI) and whether such a decrease might influence prognosis. BACKGROUND: Insulin-like growth factor-1 protects against insulin resistance and apoptosis. Although insulin resistance has been reported in AMI, IGF-1 levels have not been investigated. METHODS: We measured serum IGF-1 in 23 patients with AMI within 24 h of symptom onset and in 11 matched controls. In the first 12 patients and controls, we also measured fasting insulin, diurnal growth hormone (GH) and insulin sensitivity (assessed as glucose disappearance or T/2 after an insulin bolus), and repeated IGF-1, insulin and GH after one year. In all patients, 90-day cardiovascular death, recurrent ischemia, reinfarction, revascularization and late malignant arrhythmias were assessed. RESULTS: The AMI patients versus controls showed markedly reduced IGF-1 (115 +/- 112 vs. 615 +/- 300 ng/ml, p < 0.0001) and slower T/2 (-0.98 +/- 1.5 vs. -2.57 +/- 1.0 mg/dl/min, p = 0.01). Low IGF-1 often preceded the rise of myocardial necrosis markers. Patients with 90-day events (n = 12) versus those without had lower IGF-1 (47 +/- 54 vs. 189 +/- 110 ng/ml, p < 0.0001). Acute phase GH and insulin concentrations did not differ significantly from controls. After one year, the patients' IGF-1 values had risen to 460 +/- 242 ng/ml (p = 0.1 vs. controls, p < 0.0005 vs. acute phase), whereas GH levels were lower (0.2 +/- 0.2 vs. 2.5 +/- 2.3 ng/ml, p = 0.01) and insulin levels higher (12.5 +/- 0.2 vs. 3.9 +/- 2.6 microU/ml, p < 0.0001) compared with controls. CONCLUSIONS: In the early phase of AMI, serum IGF-1 levels are markedly reduced and may contribute to adverse outcomes. Reduced IGF-1 preceding the rise of myocardial necrosis markers suggests a possible pathogenetic role. A compensatory increase in IGF-1 appears to occur by one year.

Aged↗
PubMed2001

Multiperspective assessment of peripheral nerve involvement in diabetic patients.

To assess the relationship between peripheral nerve involvement and the patient's perception of his own quality of life, we studied 36 consecutive out-patients affected by insulin-dependent diabetes mellitus without other diabetic complications other than neuropathy (20 men, 16 women; mean age 39.1 years). We used clinical (Semmes-Weinstein, vibration perception threshold, muscle strength, osteotendinous reflexes), neurophysiological (sural, peroneal and ulnar nerves), metabolic (glycosylated haemoglobin) and patient-oriented (SF-36 and NASS questionnaires) measurements. Patient-oriented physical scores were significantly related to: (1) neurophysiological findings of the inferior limbs; (2) conventional measurements of sensitivity; (3) metabolic assessment. Conversely, patient-oriented mental scores were significantly related only to metabolic assessment. The patient-oriented measure provided an important perspective of the severity of the disease often closely related with the biological parameters and suggested new ways of interpreting conventional biological measurements. In particular, the peripheral nerve picture appeared strictly related with the physical aspects of the patients' quality of life, while the metabolic picture appeared related with both the mental and physical aspects of the quality of life.

Adult↗
PubMed2001

[Role of Helicobacter pylori infection in insulin-dependent diabetes mellitus].

BACKGROUND: Patients with insulin-dependent diabetes mellitus (IDDM) are often affected by chronic infections. H. pylori is one of the most common infection worldwide. Aim of the paper was to evaluate the prevalence of H. pylori infection, the efficacy of the most common H. pylori eradication therapies and the incidence of H. pylori reinfection after 12 months follow-up in IDDM and in a control group of dyspeptic patients matched for sex and age. METHODS: 116 IDDM patients and 50 dyspeptic controls were evaluated for H. pylori infection through 13C-urea breath test (UBT). 64 IDDM infected patients and 50 dyspeptic infected controls were randomly assigned to 3 different 7-day eradication regimens: 1) amoxicillin, clarithromycin, pantoprazole; 2) tinidazole, clarithromycin, ranitidine bismuth citrate; 3) tinidazole, clarithromycin, pantoprazole. Patients not eradicated by the first cycle were subsequently submitted to a 7-day quadruple therapy with tinidazole, tetracycline, bismuth and pantoprazole. Gastrointestinal symptoms and side effects were evaluated. Thirty-four IDDM patients and 40 dyspeptic patients previously treated for H. pylori infection and successfully eradicated (confirmed both by UBT and histology) were re-evaluated after 12 months. RESULTS: 37% of IDDM patients were infected. Mean age of IDDM infected patients was higher than negative (40+/-12 vs 32+/-10 yrs). None of the triple therapies used allowed an eradication higher than 62%. Conversely, the quadruple regimen eradicated 88% of patients. Minor side effects were observed in 10% of patients submitted to the triple therapies and in 25% of patients treated with the quadruple therapy (p<0.05). H. pylori re-infection was significantly higher in IDDM patients compared to controls: (38% vs 5% respectively, p<0.001). Mean age of IDDM re-infected patients was higher than negative (40+/-12 vs 32+/-10). Among IDDM patients daily insulin requirement and glicate haemoglobin were significantly higher in re-infected compared to uninfected patients (44+/-9 vs 35+/-8 U/I and 7,2+/-1 vs 6,8+/-0,8). CONCLUSIONS: Prevalence of H. pylori infection in IDDM patients was similar to controls. IDDM patients show a low H. pylori eradication rate with a standard triple therapy regardless of the regimen utilized. The use of a quadruple regimen leads to the cure of a large percentage of the infected patients not eradicated by the first therapy, although it is accompanied by a greater incidence of minor side effects. A significantly higher incidence of H. pylori re-infection was observed in IDDM patients when compared to not IDDM controls. The data suggest that vaccine development seems to be the only effective long run treatment for this subset of patients.

Adult↗
PubMed2000

No effect of oral insulin on residual beta-cell function in recent-onset type I diabetes (the IMDIAB VII). IMDIAB Group.

AIMS/HYPOTHESIS: Induction of tolerance to insulin is achievable in animal models of Type I (insulin-dependent) Diabetes mellitus by oral treatment with this hormone, which can lead to prevention of the disease. In the Diabetes Prevention Trial of Type I diabetes (DPT-1), oral insulin is given with the aim of preventing disease insurgence. We investigated whether if given at diagnosis of Type I diabetes in humans, oral insulin can still act as a tolerogen and therefore preserve residual beta-cell function, which is known to be substantial at diagnosis. METHODS: A double-blind trial was carried out in patients (mean age +/- SD: 14 +/- 8 years) with recent-onset Type I diabetes to whom oral insulin (5 mg daily) or placebo was given for 12 months in addition to intensive subcutaneous insulin therapy. A total of 82 patients with clinical Type I diabetes ( < 4 weeks duration) were studied. Basal C peptide and glycated haemoglobin were measured and the insulin requirement monitored every 3 months up to 1 year. Insulin antibodies were also measured in 27 patients treated with oral insulin and in 18 patients receiving placebo at the beginning of the trial and after 3, 6 and 12 months of treatment. RESULTS: The trial was completed by 80 patients. Overall and without distinction between age at diagnosis, at 3, 6, 9 and 12 months baseline mean C-peptide secretion in patients treated with oral insulin did not differ from that of those patients treated with placebo. In patients younger than 15 years a tendency for lower C-peptide values at 9 and 12 months was observed in the oral insulin group. Insulin requirement at 1 year was similar between the two groups as well as the percentage of glycated haemoglobin. Finally, IgG insulin antibodies were similar in the two groups at each time point. CONCLUSION/INTERPRETATION: The results of this study indicate that the addition of 5 mg of oral insulin does not modify the course of the disease in the first year after diagnosis and probably does not statistically affect the humoral immune response against insulin.

Administration, Oral↗
PubMed2000

Efficacy of different Helicobacter pylori eradication regimens in patients affected by insulin-dependent diabetes mellitus.

BACKGROUND: Patients with insulin-dependent diabetes mellitus (IDDM) are often affected by chronic infections; antibiotic absorption, however, may be influenced by the disease. H. pylori eradication appears to be reduced in IDDM patients. The aim of the study was to evaluate the efficacy of the most common H. pylori eradication regimens in a population of IDDM-infected patients. METHODS: One hundred and seventy-two IDDM patients were evaluated. H. pylori infection was assessed through the 13C-urea breath test. Infected patients were randomly assigned to three different standard 7-day eradication regimens: 1) amoxicillin, clarithromycin, pantoprazole; 2) tinidazole, clarithromycin, ranitidine bismuth citrate; or 3) tinidazole, clarithromycin, pantoprazole. Patients in whom eradication was not successful in the first cycle were subsequently submitted to a 7-day therapy with tinidazole, tetracycline, bismuth, and pantoprazole. RESULTS: Thirty-seven per cent of IDDM patients were infected. None of the triple therapies used provided an eradication higher than 62%. Conversely, the quadruple regimen was successful in 88% of the patients. Ten per cent of the subjects undergoing the triple therapies showed minor side effects, without significant differences among groups, whereas side effects occurred in 25% of the patients treated with the quadruple therapy (P < 0.05). CONCLUSIONS: IDDM patients show a low H. pylori eradication rate with a standard triple therapy regardless of the regimen utilized, the dosage and/or the duration of the therapy used appearing not to be sufficient to eradicate the infection efficiently. The use of a quadruple regimen leads to the cure of a large percentage of the infected patients in whom the eradication was unsuccessful in the first therapy, although it is accompanied by a greater incidence of minor side effects.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1999

Purine metabolites and malondialdehyde in platelets of diabetic patients.

The concentration of some of the purine nucleotides and their metabolites together with that of malondialdehyde (MDA) have been measured in resting and stimulated platelets of type 1 and type 2 diabetic patients. While control platelets show a net decrease of guanosine triphosphate (GTP) (3.1 vs. 2.3 nmol per 10(9) platelets) and guanosine diphosphate (GDP) (3.0 vs. 2.0 nmol per 10(9) platelets) and a significant increase of adenosine (0.04 vs. 0.55 nmol per 10(9) platelets) with platelet stimulation, platelets of type 1 and type 2 diabetic patients have a lesser change of these metabolites (GTP, 2.6 vs. 2.4; GDP, 2.3 vs. 2.4; adenosine, 0.04 vs. 0.30 (P < 0.05 vs. control) nmol per 10(9) platelets in type 1 diabetics; GTP, 2.4 vs. 2.7; GDP, 2.4 vs. 2.1; adenosine, 0.08 vs. 0.32 (P < 0.05 vs. control) nmol per 10(9) platelets in type 2 diabetics). These results indicate that the change (stimulated minus resting) of GTP, GDP and adenosine in diabetic platelets is significantly different from that of controls (P < 0.001). Moreover, the amount of MDA produced during platelet activation seems to be lower than controls only in type 2 diabetes (1.81 vs. 2.86 nmol per 10(9) platelets, P < 0.05). These results seem to indicate that a difference in the pattern of platelet nucleotides could be an important feature even in well-controlled diabetes, while MDA is probably modified only in association with the late vascular complications of diabetes.

Adenosine↗