Adaptative mechanism of the equilibrative nucleoside transporter 1 (ENT-1) and blood adenosine levels in elite freedivers.

PURPOSE: Long static or intense dynamic apnoea-like high-altitude exposure is inducing hypoxia. Adenosine is known to participate to the adaptive response to hypoxia leading to the control of heart rate, blood pressure and vasodilation. Extracellular adenosine level is controlled through the equilibrative nucleoside transporter 1 (ENT-1) and the enzyme adenosine deaminase (ADA). The aim of this study was to determine the control of adenosine blood level (ABL) via ENT-1 and ADA during apnoea-induced hypoxia in elite freedivers was similar to high-altitude adaptation. METHODS: Ten freediver champions and ten controls were studied. Biological (e.g. ENT-1, ADA, ABL, PaO2, PaCO2 and pH) and cardiovascular (e.g. heart rate, arterial pressure) parameters were measured at rest and after a submaximal dry static apnoea. RESULTS: In freedivers, ABL was higher than in control participants in basal condition and increased more in response to apnoea. Also, freedivers showed an ADA increased in response to apnoea. Finally, ENT-1 level and function were reduced for the free divers. CONCLUSION: Our results suggest in freedivers the presence of an adaptive mechanism similar to the one observed in human exposed to chronic hypoxia induced by high-altitude environment.

Adenosine plasma level correlates with homocysteine and uric acid concentrations in patients with coronary artery disease.

The role of hyperhomocysteinemia in coronary artery disease (CAD) patients remains unclear. The present study evaluated the relationship between homocysteine (HCys), adenosine plasma concentration (APC), plasma uric acid, and CAD severity evaluated using the SYNTAX score. We also evaluated in vitro the influence of adenosine on HCys production by hepatoma cultured cells (HuH7). Seventy-eight patients (mean age ± SD: 66.3 ± 11.3; mean SYNTAX score: 19.9 ± 12.3) and 30 healthy subjects (mean age: 61 ± 13) were included. We incubated HuH7 cells with increasing concentrations of adenosine and addressed the effect on HCys level in cell culture supernatant. Patients vs. controls had higher APC (0.82 ± 0.5 µmol/L vs 0.53 ± 0.14 µmol/L; p < 0.01), HCys (15 ± 7.6 µmol/L vs 6.8 ± 3 µmol/L, p < 0.0001), and uric acid (242.6 ± 97 vs 202 ± 59, p < 0.05) levels. APC was correlated with HCys and uric acid concentrations in patients (Pearson's R = 0.65 and 0.52; p < 0.0001, respectively). The SYNTAX score was correlated with HCys concentration. Adenosine induced a time- and dose-dependent increase in HCys in cell culture. Our data suggest that high APC is associated with HCys and uric acid concentrations in CAD patients. Whether the increased APC participates in atherosclerosis or, conversely, is part of a protective regulation process needs further investigations.

Tragal cartilage in tympanoplasty: anatomic and functional results in 306 cases.

Cartilage is the grafting material of choice in advanced disorders of the middle ear while the indications for its routine use remain controversial due to the possible detrimental effect on post-operative hearing. Aim of the present study was to report personal experience with "tragal cartilage shield" tympanoplasty. The study focused on 306 adult patients (236 primary procedures and 70 revisions from January 2003 to June 2007). Mean post-operative follow-up was 37 months (range 1-66). The following parameters were evaluated: graft take, change between the pre- and post-operative pure-tone average air-bone gap (PTA-ABG), post-operative complications. Graft take was achieved in 304 patients (99.35%) and there were no immediate post-operative complications. The overall average pre-operative pure-tone average air-bone gap was 43.79 +/- 7.07 dB, whereas the post-operative (1 year after surgery) pure-tone average air-bone gap was 10.43 +/- 5.25 dB (p < 0.0001). Statistically significant improvement was observed up to 5 years after surgery. This study reveals that tragal cartilage shield tympanoplasty is a reliable technique, in fact it has a high degree of graft take and hearing results are satisfactory. Furthermore, the cartilage is a satisfactory grafting material because it is easily accessible, easy to adapt, resistant to negative middle ear pressures, stable, elastic, well tolerated by the middle ear, resistant to resorption. Therefore, we also recommend its use in less severe middle ear disorders, in which the functional outcome is more essential.

Negative stress echo: further prognostic stratification with assessment of pressure-volume relation.

BACKGROUND: A maximal negative stress echo identifies a low risk for subsequent hard events subset. However, the potentially prognostically relevant information on global contractile reserve on the left ventricle is missed by standard regional wall motion assessment, and can be obtained by end-systolic pressure-volume relationship (PVR) evaluation. AIM: To assess the relative prognostic value of PVR in patients with negative stress echo. METHODS: We enrolled 99 consecutive patients (age=61+/-14 years; 81 males, LVEF 47+/-14%, WMSI=1.42+/-0.50) with negative exercise stress echo for standard wall motion criteria. To build the PVR, the force was determined at rest and peak stress as the ratio of the systolic pressure/end-systolic volume index. All patients were followed-up on medical therapy. RESULTS: Median follow-up was 21 months (interquartile range 12-26). Twenty-nine events have been observed: 6 deaths, 10 heart failure related hospitalization and 13 worsening NYHA class of >or=1 grade. Using Cox's proportional hazard model the best independent predictor of total events was SP/ESV index change (rest-stress) <1.5 mm Hg/ml/m(2) as determined by ROC analysis cut-off (RR=29, p=0.001, sensitivity=80%, specificity=93%). The overall survival and event-free survival was 34% in patients with change (rest-stress) SP/ESV index<1.5 mm Hg/ml/m(2) and 97% in whose with >1.5 mm Hg/ml/m(2). CONCLUSIONS: In patients with negative stress echo, a preserved global contractility response can be easily identified through stress-induced variation in SP/ESV index, with powerful further risk stratification.

Stress induced cardiomyopathy presenting as acute coronary syndrome: Tako-Tsubo in Mercogliano, Southern Italy.

BACKGROUND: Tako-tsubo syndrome (TTS) in its typical (apical) and atypical (non-apical) forms is being increasingly recognized in the West owing to early systematic coronary angiography in acute coronary syndromes (ACS). AIM OF THE STUDY: To assess the incidence, the clinical characteristics and the outcome of TTS in a single high volume cath lab in Southern Italy over the last 6 years. METHODS: Among 1674 consecutive patients (pts) referred to our coronary care units in the last 6 years (2001-2006) for ACS we selected 6 (0.5%) pts (6 women; age 57 +/- 6 years) who fulfilled the following 4 criteria: 1) transient left ventricular wall motion abnormalities resulting in ballooning at contrast ventricolographic or echocardiographic evaluation; 2) normal coronary artery on coronary angiography performed 5 +/- 9 hours from hospitalization; 3) new electrocardiographic ischemic-like abnormalities (either ST-segment elevation or T-wave inversion) and 4) emotional or physical trigger event. RESULTS: At admission all pts had presumptive diagnosis of ACS and ECG revealed ST elevation in 3 (50%) and T wave inversion with QT elongation in 3 (50%). In the acute phase cardiogenic shock occurred in 2 (33%) and heart failure in 1(16%). Presenting symptoms were chest pain in 6 (100%), dyspnoea in 2 (33%) and lipotimia in 1 (16%). At echocardiographic-ventricolographic assessment, the mechanical dysfunction (ballooning) was apical in all 6 pts ("classic" TTS). In all patients wall motion abnormalities completely reversed within 4.5 +/- 1.5 days. The region of initial recovery was the anterior and lateral wall in 4 cases and the lateral wall in 2 cases. Ejection fraction was 35 +/- 8% in the acute phase and increased progressively at discharge (55 +/- 6%) and at 41 +/- 20 months follow-up (60 +/- 4%, p < 0.001 vs. baseline). All patients remained asymptomatic with minimal (aspirin, beta blockers, antihypertensive and antidislipidemic therapy) treatment. CONCLUSION: Classic TTS is a frequent serendipitous diagnosis after coronary angiography showed "surprisingly" normal findings in a clinical setting mimicking an ACS. Despite its long-term good prognosis life threatening complications in the acute phase can occur.

Evaluation of ultrasound lung comets by hand-held echocardiography.

BACKGROUND: Ultrasound lung comets (ULCs) are a clinically useful sign of extravascular lung water. They require very limited technology (2 D-echo), and a short learning curve. The aim of the present study is to compare ULCs information obtained by experienced echocardiologists using a full feature echocardiographic platform and by inexperienced sonographers using a hand-held echocardiography system. METHODS: 20 consecutive in-hospital patients underwent, within 15' and in random order, 2 ultrasound examinations for ULCs by 2 observers with different specific expertise and different technology: 1) "high-tech veteran": ULCs assessment with full feature echocardiographic platform (HP Sonos 7500 Philips Medical Systems, Andover, MA, USA) by a trained echocardiologist, with > or =2 years expertise in ULCs assessment and accredited by the European Association of Echocardiography; 2) and a "low-tech beginner": ULCs assessment with hand-held echocardiography (Optigo; Philips, Andover, MA) by an echocardiographer with very limited (30') dedicated training on ULCs assessment. In each patient, ULC score was obtained by summing the number of comets from each of the scanning spaces in the anterior right and left hemithorax, from the second to the fifth intercostal space. RESULTS: There was a significant, tight correlation (r = .958, p < 0.001) between the 2 observations in the same patient by "high-tech veteran" and "low-tech beginner". CONCLUSION: ULCs are equally reliable in the hands of highly experienced echocardiologists using full feature echocardiographic platforms and in the hands of absolute beginners with miniaturized, compact, and battery-equipped echocardiographic systems. From the technological and expertise viewpoint, ULCs are the "kindergarten" of echocardiography, ideally suited for bedside evaluation of patients with both known or suspected heart failure.

Assembly of HCV E1 and E2 glycoproteins into coronavirus VLPs.

Hepatitis C virus (HCV) is believed to assemble by budding into membranes of the early secretory pathway, consistent with the membrane location where the viral envelope glycoproteins E1 and E2 accumulate when expressed. Coronavirus assembly also takes place at pre-Golgi membranes. Here, we generated coronavirus-like particles carrying in their envelope chimeric HCV glycoproteins composed of the ectodomains of E1 and E2, each fused to the transmembrane plus endodomain of the mouse hepatitis coronavirus spike glycoprotein. The chimeric particle system will enable structural and functional studies of the HCV glycoproteins.

Benign paroxysmal positional vertigo: a study of two manoeuvres with and without betahistine.

Efficacy of the liberatory manoeuvre and of gradual otolitis dispersion technique, with or without associated drug therapy, have been compared. Included in this prospective study were 103 patients with benign paroxysmal positional vertigo seen in the Outpatient Department. Patients were classified into 4 groups according to treatment: Liberatory Manoeuvre according to methods described by Semont et al., with and without betahistine, Gradual Otolitis Dispersion Technique according to Brandt and Daroff, with and without betahistine. Evaluation was performed at baseline and at 3, 7, 14, 30, 60 and 90 days after start of treatment. Response to treatment was evaluated using criteria of Epley. At day 14, liberatory manoeuvre-betahistine and Brandt and Daroff-betahistine groups did significantly better than liberatory manoeuvre and Brandt and Daroff groups (p < 0.05). Improvement reached at day 30 was: 100% in liberatory manoeuvre-betahistine group; 96.30% (p > 0.05) in Brandt and Daroff-betahistine group; these results were significantly better (p < 0.05) than those of liberatory manoeuvre (54.17%) and Brandt and Daroff (25%) groups. As far as concerns differences between disease onset and start of therapy (less and more than 2 weeks), and age (< or =60 years and > or =60 years), response to treatment was similar. In conclusion, both liberatory manoeuvre and Brandt and Daroff, when associated with betahistine, were significantly more effective than manoeuvres alone (p < 0.05). Improvement in liberatory manoeuvre-betahistine group, in the initial phase, was greater that in Brandt and Daroff-betahistine group, albeit, differences were not significant (p > 0.05). Age-related effects of manoeuvres were compared in 71 patients < 60 years and 32 patients > or =60 years, showing a similar improvement rate at the end of the investigation in both groups. In our opinion, liberatory manoeuvre and Brandt and Daroff associated with betahistamine produces faster recovery compared to liberatory manoeuvre and Brandt and Daroff alone. Nevertheless, 3 months after onset of treatment, all patients showed complete recovery due to spontaneous evolution of paroxysmal positional vertigo, in other words, treatment does not appear to influence the final improvement rate and its role should be accepted as a significant reduction in persistence of symptoms.

Stress echocardiography.

Stress echocardiography is the combination of 2D echocardiography with a physical, pharmacological or electrical stress. The diagnostic end point for the detection of myocardial ischemia is the induction of a transient worsening in regional function during stress. Stress echocardiography provides similar diagnostic and prognostic accuracy as radionuclide stress perfusion imaging, but at a substantially lower cost, without environmental impact, and with no biohazards for the patient and the physician. Among different stresses of comparable diagnostic and prognostic accuracy, semisupine exercise is the most used, dobutamine the best test for viability, and dipyridamole the safest and simplest pharmacological stress and the most suitable for combined wall motion--coronary flow reserve assessment. The additional clinical benefit of myocardial contrast echocardiography, tissue Doppler imaging and real time 3-D echocardiography has been inconsistent and disappointing, whereas the potential of adding coronary flow reserve evaluation of left anterior descending coronary artery by transthoracic Doppler echocardiography adds another potentially important dimension to stress echocardiography. In spite of its dependence upon operator's training, stress echocardiography is today the best possible imaging choice to achieve the still elusive target of sustainable cardiac imaging in the field of noninvasive diagnosis of coronary artery disease.

A new determinant of endoplasmic reticulum localization is contained in the juxtamembrane region of the ectodomain of hepatitis C virus glycoprotein E1.

Hepatitis C virus glycoproteins E1 and E2 do not reach the plasma membrane of the cell but accumulate intracellularly, mostly in the endoplasmic reticulum. Previous studies based on transient expression assays have shown that the transmembrane domains of both glycoproteins are sufficient to localize reporter proteins in the endoplasmic reticulum and that other localization signals may be contained in the ectodomain of E1 protein. To identify such signals we generated chimeric proteins between E1 and two reporter proteins, the human CD8 glycoprotein and the human alkaline phosphatase, and analyzed their subcellular localization in stable as well as transient transfectants. Our results showed that (i) an independent localization determinant for the endoplasmic reticulum is present in the juxtamembrane region of the ectodomain of E1 protein and (ii) the localization dictated by this determinant is either due to direct retention or to a recycling mechanism from the intermediate compartment/cis-Golgi complex region, which is clearly different from those previously described for other retrieval signals. These results show for the first time in mammalian cells that the localization in the endoplasmic reticulum of transmembrane protein can be determined by specific targeting signals acting in the lumen of the compartment.

Sex-related influence of body size and sexual maturation on blood pressure in adolescents.

OBJECTIVE: This study is aimed at investigating the influence of body size, body fat and sexual maturation on blood pressure (BP) in adolescents. DESIGN: A cross-sectional study. SETTING: A suburban student population of Southern Italy. SUBJECTS: One hundred ninety students attending the first and second year of a secondary school. Five were excluded because they were affected by major diseases. The remaining were 98 M and 87 F (mean age for either group = 12.0+/-0.8 y). METHODS: Blood pressure was measured by a mercury sphygmomanometer, body weight by a platform beamscale, other measurements included height, biceps, triceps, subscapular and suprailiac skinfolds by a caliper; sexual maturation was evaluated according to Tanner. RESULTS: Body size was greater than in Tanner's population: in particular body weight (but not height) in our sample markedly exceeded that of the children of the same age in Tanner's population. Boys had higher systolic blood pressure (SBP) than girls (BP = 109/64+/-12/10 vs. 103/63+/-11/8 mm Hg, P<0.02 for SBP), while heart rate and waist/hip ratio were lower. During puberty evaluated on the basis of pubic hair growth BP in girls was higher than in the prepubertal phase (107/66+/-9/7 vs. 99/61+/-10/7, P<0.01). Pubertal boys showed a reduced percent of body fat (calculated from four skinfold measurements) in comparison to prepubertal ones (21.0%+/-4.5 vs. 24.5%+/-7.1, P<0.01). In linear correlation analysis, height, BW, BMI and lean body mass were found to be significantly associated with SBP in both sexes and to diastolic blood pressure (DBP) in girls. Percent body fat was correlated with SBP in boys, while sexual maturation was associated to SBP and DBP in girls only. Multiple regression analysis indicated a significant contribution of body size to BP variability, particularly in the girls. Sexual maturation was excluded from the final regression equations when height, BW or lean body mass were present. CONCLUSIONS: These data indicate that body weight in these adolescents is greater that in Tanner's population of the same age and sex. Body size appears to be a major determinant of BP, whereas sexual maturation seems to influence BP levels mainly through body growth. The influence of percent body fat on BP setting seems to be of limited importance.

Reducing intergroup bias: elements of intergroup cooperation.

The authors examined the potentially separable contributions of 2 elements of intergroup cooperation, interaction and common fate, and the processes through which they can operate. The manipulation of interaction reduced bias in evaluative ratings, which supports the idea that these components are separable, whereas the manipulation of common fate when the groups were interacting was associated with lower bias in nonverbal facial reactions in response to contributions by in-group and out-group members. Whereas interaction activated several processes that can lead to reduced bias, including decategorization, consistent with the common in-group identity model (S. L. Gaertner, J. F. Dovidio, P. A. Anastasio, B. A. Bachman, & M. C. Rust, 1993) as well as M. Hewstone and R. J. Brown's (1986) group differentiation model, the primary set of mediators involved participants' representations of the memberships as 2 subgroups within a superordinate entity.

A different intracellular distribution of a single reporter protein is determined at steady state by KKXX or KDEL retrieval signals.

To establish the specific contribution to protein topology of KKXX and KDEL retrieval motifs, we have determined by immunogold electron microscopy and cell fractionation the intracellular distribution at steady state of the transmembrane and anchorless versions of human CD8 protein, tagged with KKXX (CD8-E19) and KDEL (CD8-K), respectively, and stably expressed in epithelial rat cells (Martire, G., Mottola, G., Pascale, M. C., Malagolini, N., Turrini, I., Serafini-Cessi, F., Jackson, M. R., and Bonatti, S. (1996) J. Biol. Chem. 271, 3541-3547). The CD8-E19 protein is represented by a single form, initially O-glycosylated: only about half of it is located in the endoplasmic reticulum, whereas more than 30% of the total is present in the intermediate compartment and cis-Golgi complex. In the latter compartments, CD8-E19 colocalizes with beta-coat protein (COP) (COPI component) and shows the higher density of labeling. Conversely, about 90% of the total CD8-KDEL protein is localized in clusters on the endoplasmic reticulum, where significant co-localization with Sec-23p (COPII component) is observed, and unglycosylated and initially O-glycosylated forms apparently constitute a single pool. Altogether, these results suggest that KKXX and KDEL retrieval motifs have different topological effects on theirs own at steady state: the first results in a specific enrichment in the intermediate compartment and cis-Golgi complex, and the latter dictates residency in the endoplasmic reticulum.

Different fate of a single reporter protein containing KDEL or KKXX targeting signals stably expressed in mammalian cells.

In mammalian cells, resident luminal and type I transmembrane proteins of the endoplasmic reticulum usually contain KDEL and KKXX at the carboxyl terminus. These sequences induce retrieval from compartments located downstream in the secretory pathway. It has been suggested that the retrieval may occur from multiple sites, ranging from the intermediate compartment to the trans-Golgi network. To compare the retrieval of luminal and type I membrane proteins, we have used different forms of a single reporter, the human CD8 glycoprotein, stably expressed in FRT cells. Metabolic labeling and oligosaccharide analysis show that the mechanism based on the KDEL signal is leaky. With time, the KDEL-containing CD8 form reaches the trans/trans-Golgi network compartments, where the protein is terminally glycosylated. At this stage, the retrieval mechanism stops being effective and the protein is consequently secreted. Conversely, the mechanism based on the KKXX signal guarantees that most of the KKXX-containing CD8 form resides in the endoplasmic reticulum, little in the Golgi complex and undetectable levels at the plasma membrane. The O-glycosylation of this protein comprises for the vast majority the sole addition of peptide-bound GalNAc that occurs in an early Golgi compartment.

Left ventricular thrombus and myocardial infarction.

The aim of our study was to determine whether a relationship existed between echocardiographic evidence of left ventricular thrombus (LVT) and clinical course of myocardial infarction. We followed 143 patients who had had typical myocardial transmural infarction (82 with "anterior") and 61 with "inferior" myocardial infarction) over a three month period. Incidence of LVT, detected by Two-Dimensional Echocardiography (TDE) was significantly greater in subjects affected by "anterior" myocardial infarction (p less than 0.05). Furthermore, the occurrence of LVT was more frequent in the presence of left ventricular a-, dys-kinesis detected by TDE (p less than 0.01). No significant relationship was demonstrated either with the occurrence of severe ventricular arrhythmias (Lown 3-4-5) or with an abnormal stressing test performance. Thus certain clinical and laboratory features such as anterior site of infarction, higher serum level of CPK and CPK-MB and severe alterations of left ventricular kinesis proved to be useful in identifying a subset of patients most likely to have LVT who may benefit from early anticoagulant therapy.

[Mono and bidimensional echocardiographic control in patients surgically treated by abdominal apical conduit (author's transl)]. / Possibilita' di controllo ecocardiografico mono- e bidimensionale in pazienti operati di condotto apico-aortico addominale.

Creation of a double outlet left ventricle by means of an apical conduit may solve the problems related to left ventricular outflow tract obstructions which are not amenaable to conventional surgical management. Searching a diagnostic method easily applicable, repeatable and reliable, the results obtained with serial echocardiographic controls have been evaluated. This technique has shown to be of great value in answering several hemodynamic questions. An echocardiographic protocol has been developed for the follow-up of these patients.

[A proposed hepatic pie chart]. / Progetto di istantanea epatica.

The AA. have chosen 12 tests to organize an "hepatic flash" after a selection out of 180 cases scheduled as the table no. I through a set of tests showing step by step any modifications in compliance with the sensibility, reliability, statistical clinical and physio-pathological meaning of each test. The 12 tests are set out by circular abscissae of a circus according to the pathogenetic mechanisms leading to their modifications. By the radial ordinates, instead, it is shown the decreasing and increasing values which every test may assume. An hypothetic line (hepatogram) links then the values set out during the process of the disease in such a manner that the particular shapes assumed by the line itself show quickly and visually the spreading rate of the disease process.