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A Achilli

Publications and source records attributed to A Achilli.

17 recordsLinked to original sources
PubMed2006

The 13042G --> A/ND5 mutation in mtDNA is pathogenic and can be associated also with a prevalent ocular phenotype.

BACKGROUND: Overlapping phenotypes including LHON, MELAS, and Leigh syndrome have recently been associated with numerous mtDNA point mutations in the ND5 gene of complex I, now considered a mutational hot spot. OBJECTIVE: To identify the mtDNA defect in a family with a prevalent ocular phenotype, including LHON-like optic neuropathy, retinopathy, and cataract, but characterised also by strokes, early deaths, and miscarriages on the maternal line. RESULTS: Sequencing of the entire mitochondrial genome from the proband's muscle DNA identified the heteroplasmic 13042G-->A transition, which was previously described only once in a patient with a different mitochondrial disease. This mutation fulfils the major pathogenic criteria, inducing an amino acid change (A236T) at an invariant position in a highly conserved domain of the ND5 gene. Phosphorus magnetic resonance spectroscopy in the proband disclosed an in vivo brain and skeletal muscle energy metabolism deficit. CONCLUSIONS: These findings conclusively establish the pathogenic role of the 13042G-->A mutation and underscore its variable clinical expression.

Base Pair Mismatch↗
PubMed2005

Subtyping mtDNA haplogroup H by SNaPshot minisequencing and its application in forensic individual identification.

Sequence variation of the hypervariable segments (HVS) I/II of mitochondrial DNA (mtDNA) and the haplogroup affiliation were determined in a sample of 271 Italian subjects. This analysis showed that 42% of the individuals could be ascribed to H, the most frequent haplogroup in European Caucasian populations. This fraction was then screened for specific single nucleotide polymorphisms located in the coding region to identify H subclades H1-H15. We set up two multiplex polymerase chain reactions and specific SNaPshot assays to investigate the frequency distribution of these subgroups in our population sample and to examine their usefulness in discriminating among commonly shared HVS I/II sequences. This allowed the assignment of a large portion of the mtDNAs ( approximately 70%) to specific subhaplogroups, with H1 and H5 being the most represented. About two-thirds of the individuals sharing common HVS I/II sequences were subdivided and ascribed to specific H subhaplogroups with a significant reduction of the frequencies of the most common mtDNA haplotypes. Haplogroup H subtyping could thus be extremely useful in forensic identification when many samples have to be analysed and compared, avoiding excessive time-consuming and labor-intensive sequencing analysis.

Complementarity Determining Regions↗
PubMed2005

The peopling of modern Bosnia-Herzegovina: Y-chromosome haplogroups in the three main ethnic groups.

The variation at 28 Y-chromosome biallelic markers was analysed in 256 males (90 Croats, 81 Serbs and 85 Bosniacs) from Bosnia-Herzegovina. An important shared feature between the three ethnic groups is the high frequency of the "Palaeolithic" European-specific haplogroup (Hg) I, a likely signature of a Balkan population re-expansion after the Last Glacial Maximum. This haplogroup is almost completely represented by the sub-haplogroup I-P37 whose frequency is, however, higher in the Croats (approximately 71%) than in Bosniacs (approximately 44%) and Serbs (approximately 31%). Other rather frequent haplogroups are E (approximately 15%) and J (approximately 7%), which are considered to have arrived from the Middle East in Neolithic and post-Neolithic times, and R-M17 (approximately 14%), which probably marked several arrivals, at different times, from eastern Eurasia. Hg E, almost exclusively represented by its subclade E-M78, is more common in the Serbs (approximately 20%) than in Bosniacs (approximately 13%) and Croats (approximately 9%), and Hg J, observed in only one Croat, encompasses approximately 9% of the Serbs and approximately 12% of the Bosniacs, where it shows its highest diversification. By contrast, Hg R-M17 displays similar frequencies in all three groups. On the whole, the three main groups of Bosnia-Herzegovina, in spite of some quantitative differences, share a large fraction of the same ancient gene pool distinctive for the Balkan area.

Bosnia and Herzegovina↗
PubMed2003

Electrocardiographic pattern of Brugada syndrome disclosed by a febrile illness: clinical and therapeutic implications.

BACKGROUND: Recent studies have identified a direct link between the ionic mechanisms responsible for the electrocardiographic (ECG) pattern of the Brugada syndrome (BS) and the in vitro experimental temperature, pointing to the possibility that some BS patients may display the ECG phenotype only during a febrile state, being in this setting at risk of lethal arrhythmias. CASE REPORT: A 53-year-old man referred to the emergency room for abdominal pain and fever. The ECG showed dome-shaped ST-segment elevation in V1-V3, as in the typical BS. The personal and family history were unremarkable for syncope and sudden death and physical, laboratory and ultrasound examinations were negative. On day 3, at normal body temperature, the patient's ECG returned to normal and the ECG abnormalities were later reproduced with intravenous flecainide. The patient refused the implantation of a loop recorder and was discharged after 6 days. He has remained asymptomatic during 2 years of follow-up. CONCLUSIONS: The typical ECG phenotype of BS disclosed by a febrile illness confirms the in vitro experimental data that previously established a correlation between ECG pattern of BS and temperature variations. The clinical and therapeutic implications of these findings are discussed.

Bundle-Branch Block↗
PubMed2001

Stationary-phase mutations in proofreading exonuclease-deficient strains of the yeast Saccharomyces cerevisiae.

In order to understand the role of yeast polymerases in spontaneous mutagenesis in non-growing cells we have studied the effects of mutations that impair the 3'--> 5' exonuclease function of polymerases delta (pol3-01) and epsilon (pol2-4) on the spontaneous reversion frequency of the frameshift mutation his7-2 in cells starved for histidine. We showed that for each exonuclease-deficient mutant the rate of reversion per viable cell per day observed in stationary-phase cells remained constant up to the 9th day of starvation (while the number of viable cells dropped), and was very similar to that observed in the same mutants during the growth phase. These data suggest that both DNA polymerases are involved in the control of mutability in non-growing cells.

DNA Polymerase II↗
PubMed2000

[Long-term clinical assessment of single-lead VDD electric stimulation].

BACKGROUND: During the last decade single lead VDD pacing has been progressively affirmed as an electrotherapy of choice in patients with advanced atrioventricular block without alterations of the sinus function. It combines the benefits of P-synchronous ventricular pacing with an easy implant procedure when compared to the conventional DDD approach. The aim of this study was to evaluate the validity of such an approach in a large population of patients, all implanted in a single center. METHODS: From 1987 up to now, 317 patients, all affected by advanced atrioventricular block and without sinus node dysfunction, were implanted in our center with a single lead VDD pacemaker. During follow-up the persistence of a proper atrioventricular synchronization was assessed and evaluated. RESULTS: The mean follow-up was 3.9 +/- 2.7 years/patient (range 6-138 months). The 94.6% of implanted systems maintained the normal VDD pacing function. Permanent reprogramming in VVI mode was necessary in 17 patients (5.36%); in 12 (3.78%) because of chronic atrial fibrillation and in 5 (1.63%) for loss of atrial sensing. The percentage of atrial synchronization was optimal (> 98%) and acceptable (> 95%) in 81% and 19% of patients, respectively. Episodes of paroxysmal atrial fibrillation occurred in 3 patients. Neither inhibition by myopotentials nor occurrence of sinus node disease was observed during follow-up. These results are in accordance with those reported by previous studies, performed on a smaller population or on a multicenter basis, and are comparable with the results reported for conventional DDD pacemaker. CONCLUSIONS: Our results confirm the high reliability of the single lead VDD pacing system concerning the long-term persistence of a proper atrioventricular synchronization. Data showed above enforce our opinion that this pacing approach should be considered the treatment of choice in patients with advanced atrioventricular block and preserved sinus node function.

Aged↗
PubMed1996

Identification of viable myocardium by nitrate echocardiography after myocardial infarction: comparison with planar thallium reinjection scintigraphy.

BACKGROUND: The aim of this study was to validate a new diagnostic tool, nitrate echocardiography (NE), for the identification of viable noncontracting myocardium in patients with a history of prior myocardial infarction (MI). Nitroglycerin (NTG) may be useful for this purpose for its peculiar pharmacodynamic action and may represent an option other than dobutamine echocardiography for the detection of hibernating segments in the presence of severely reduced coronary reserve. METHODS: Twenty selected patients (pts) with an old MI were studied with NE and planar thallium scintigraphy with reinjection. NE was performed by administering i.v. NTG starting at 0.4 mcg/kg/minute with equal increments every five minutes up to 2 mcg/kg/minute or to early interruption of the test (decrease of systolic blood pressure > or = 20% or improvement of previously akinetic segments). Left ventricular wall motion was analyzed by dividing the left ventricle (LV) into 16 segments, and a wall motion score index (WMSI) was calculated. Thallium images were obtained at peak exercise, at four hours, and after reinjection. Myocardial viability was defined as an improvement in thallium uptake after reinjection in fixed defects. RESULTS: Basal echo demonstrated 74 akinetic segments; of these 21 (28%, 11 pts) showed improved contractility during NTG infusion at a mean dose of 0.87 +/-0.33 mcg/kg/minute. WMSI decreased from 1.69 +/- 0.29 to 1.46 +/- 0.31 (P = .001). The only hemodynamic response was a drop in systolic blood pressure (136 mmHg to 124; P = .02). Thallium studies showed 29 segments with a four-hour reversible defect and 79 segments with a four-hour fixed defect; of the latter, 14 regions demonstrated improvement in tracer uptake after reinjection (17.7%; 10 pts). Nine pts had a positive echo and thallium study, while 8 showed no improvement either during NE or after thallium reinjection. Two pts had a false-positive nitrate echocardiogram. Therefore, according to an echo/thallium study match, sensitivity, specificity, and accuracy are 90%, 80%, 85%, respectively. CONCLUSION: NE is a reliable and low-cost method for the detection of viable noncontracting myocardium in selected patients with CAD but needs further validation for widespread application.

Aged↗
PubMed1995

Acute myocardial infarction shortly after a normal exercise stress test. Case reports.

The authors describe 3 cases of AMI occurring shortly after a negative bicycle ergometer stress test. These cases represent an unfortunate but extremely rare complication of a relatively safe diagnostic procedure. The authors also focus on the pathogenesis of the ischemic event, which may be attributed either to intraplaque hemorrhage or to platelet aggregation, both exercise-induced. The prevalence of AMI in this paper (0.06%) is similar to the data described in literature.

Adult↗
PubMed1994

Bifascicular block complicating blunt cardiac injury. A case report and review of the literature.

A thirty-five-year-old horse trainer presented to the emergency room of the authors' hospital with minimal nonpenetrating chest injury after having been kicked by a horse. No rib or sternum fractures were demonstrated. The admission ECG demonstrated a right bundle branch block and a left anterior hemiblock that were previously absent. The authors are aware of only two similar reports, but analogous conduction disturbances might have been classified as intraventricular conduction defects. The rarity of these defects may be explained by the anatomic pathways of the bundle of His and its bifurcations.

Adult↗
PubMed1993

[The echo-nitrate test for the detection of viable myocardium after a myocardial infarct: a comparison with delayed-acquisition thallium scintigraphy].

BACKGROUND: The aim of this study was to evaluate the ability of echocardiography, associated with nitroglycerin infusion, in the detection of myocardial viability in patients with recent infarction. PATIENTS AND METHODS: Fourteen patients (11 male, 3 female, mean age 59 +/- 8 years) with first acute myocardial infarction (12 Q wave, 2 non-Q wave) underwent predischarge (18 +/- 3 days) nitrate echocardiography. All patients underwent delayed planar thallium scintigraphy within four weeks from AMI. Nitrate echocardiography was performed with a nitroglycerin infusion starting from 0.4 mcg/Kg/min every 5 minutes up to 2.0 mcg/Kg/min; the test was terminated with an improvement of wall motion abnormalities or with a drop of systolic blood pressure > or = 20%. Wall motion abnormalities were evaluated with a 16-segment wall motion score index (WMSI). Thallium was performed after a symptom-limited exercise test, after 3 and 24 hours. The left ventricle was divided in 15 regions. Thallium was considered the gold standard for myocardial viability. RESULTS: Basal echo identified 59 dyssynergic segments: of these, 12 (20%-6 patients) showed improvement in contractility during nitrate echocardiography at a mean dose of 0.9 +/- 0.3 mcg/Kg/min. WMSI decreased from 1.42 +/- 0.22 to 1.27 +/- 0.13 (p = 0.022), with no significant change of haemodynamic data (mean systolic blood pressure from 125 to 112 mmHg; mean heart rate from 66 to 76 beats/min; mean rate/pressure product from 8415 to 8848; all p = ns). Thallium scintigraphy showed 40 fixed defects (19%-7 patients) and 10 (4.7%-7 patients) late reversible defects. 20% of the 3-hour fixed defects improved at 24-hour imaging. 5/7 patients with echo improvement had 24-hour reversible defects, while 6/7 with no WMSI improvement had 24-hour fixed defects. Therefore, nitrate echocardiography demonstrated 71% sensitivity, 86% specificity, 83% positive predictive value, 75% negative predictive value and 78% accuracy. CONCLUSIONS: Nitrate echocardiography may be a feasible and low cost method in the detection of myocardial viability after myocardial infarction, but awaits further validation.

Aged↗
PubMed1983

[Aortic pseudo-valvular image with diastolic eccentricity of the semilunaris. A specific sign of aortic dissection?].

M-mode and two-dimensional echocardiograms were obtained in a patient with aortic dissection (De Bakey type 1). The M-mode echocardiogram showed an image resembling to an aortic valve with a left coronary cusp and eccentric diastolic echoes. The M-mode and two-dimensional echocardiograms recorded at a more distal level showed that this image was produced by the systo-diastolic movements of the torn intima. Such an echocardiographic finding should suggest the presence of an aortic dissection.

Aortic Dissection↗
PubMed1981

[Digoxin-quinidine and digoxin-amiodarone interactions. Effects on blood levels of the cardioactive glycoside].

With ever increasing frequency potentially dangerous interactions are reported between Cardiac Glycosides and other drugs, particularly the antiarrhythmic one. The AA, carried out this work with the intent of studying the possible modifications produced by Q and A on the SDL. First of all the AA. retrospectively studied the SDL of patients treated with the associations Q-D and A-D and this SDL was compared with the SDL of patients treated with D alone. Then 10 subjects treated sequentially, at first with D alone and after with the Q-D (5 p.) and A-D (5 p.) association, were studied. The results obtained confirm the data of other AA. regarding the Q-D interaction; in fact, in the presence of this antiarrhythmic drug, the SDL increase significantly following the concomitant pharmacological effects of the Cardiac Glycosides. The SDL on the contrary seem not be influenced by the A-D association. The AA. then reviewed the literature about the mechanism of the Q-D interaction. The majority of the AA. agree outlining a reduction of the Volume of Distribution and of D Clearance, in consequence of the concomitant administration of Q, which would explain the high SDL obtained. In conclusion the AA. suggest, when the Q-D association is mandatory, a 50% reduction of the D maintenance dose and to check periodically the ECG and SDL.

Adult↗
PubMedDate not supplied

Osteonecrosis of the jaws in patients treated with bisphosphonates. Review of the literature and the Milan experience.

AIM: A series of 5 patients with osteonecrosis of the jaws possibly related to the use of bisphosphonates is presented. A brief review of the literature is also proposed. METHODS: A retrospective review of patients who received bisphosphonates and who developed osteonecrosis of the jaws following minor oral surgery was performed. RESULTS: In all 5 patients, a tooth extraction preceded the onset of osteonecrosis of the mandible. Patients were on chronic use of intravenous bisphosphonates. The presenting lesions was a nonhealing extraction socket and an exposed jawbone. Biopsy of the bone lesions showed no evidence of metastatic involvement. Antibiotic therapy, conservative debridement and, in some cases, bone sequestrectomy were performed. CONCLUSIONS: Osteonecrosis of the jaws appears to have a relationship with the use of bisphosphonates. It is important that medical oncologists and dentists become aware of this possible complication in order to perform minor oral surgery prior to starting bisphosphonates treatment.

Aged↗