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This paper reports the first experimental observation of phonons and their softening on single crystalline LaPt2Si2 via inelastic neutron scattering. From the temperature dependence of the phonon frequency in close proximity to the charge density wave (CDW) q-vector, we obtain a CDW transition temperature of TCDW = 230 K and a critical exponent β = 0.28 ± 0.03. This value is suggestive of a non-conventional critical behavior for the CDW phase transition in LaPt2Si2, compatible with a scenario of CDW discommensuration (DC). The DC would be caused by the existence of two CDWs in this material, propagating separately in the non equivalent (Si1–Pt2–Si1) and (Pt1–Si2–Pt1) layers, respectively, with transition temperatures TCDW−1 = 230 K and TCDW−2 = 110 K. A strong q-dependence of the electron-phonon coupling has been identified as the driving mechanism for the CDW transition at TCDW−1 = 230 K while a CDW with 3-dimensional character, and Fermi surface quasi-nesting as a driving mechanism, is suggested for the transition at TCDW−2 = 110 K. Our results clarify some aspects of the CDW transition in LaPt2Si2 which have been so far misinterpreted by both theoretical predictions and experimental observations and give direct insight into its actual temperature dependence.

Background: Obesity is often associated with cardiovascular pathology. Cardiac arrhythmias and sudden death are reported for obese subjects during severe caloric restriction and weight loss. Also obese patients without dieting are at increased risk of arrhythmias and sudden death in the absence of cardiac dysfunction. This is probably due to a delayed cardiac repolarization and prolongation of heart rate corrected electrocardiographic QT interval (QTc)., Methods: This paper examined the electro-cardiographic findings of a group of obese young males compared with normal patients and whether QTc interval duration was associated with relative body mass index. All patients were free of cardiovascular diseases and came to the First Aid Department for other pathology than cardiac. We studied 109 subjects (50 obese males and 59 normal males; aged 43.4+/-14.8 and 42.8+/-9.8 years respectively)., Results: Obese patients presented a shorter PQ, a prevalence of left cardiac axis, a higher heart rate, a longer QT, but not QTc compared with normal males. There was no correlation between QTc and obesity., Conclusions: This study noticed that obese patients present some differences in electrocardiographic findings compared with normal subjects and that these alterations are not ascribed to cardiac repolarization. This is probably due to the young age of the studied groups.

In this study we evaluated the potential differences in normal electrocardiographic parameters between two groups of young patients belonging to different races (Caucasians and Blacks). For this purpose 100 electrocardiograms had been taken, coded and compared in 50 Italian males and 50 north-Africans who came to an Emergency Department because of minor condition. On the whole we could not find significant differences between the two groups, except for a small increase in P-wave duration in black people. We conclude that the same parameters used to evaluate normal electrocardiograms in white people, may be satisfactory applied also for black individuals. This fact is worthy of attention since more and more extracomunitarian patients are addressing the Italian Health Service.

Herpes zoster (HZ) is a common skin disease due to a virus identical to that responsible for chickenpox. In a variable number of cases neuritic pain persist after cutaneous healing. Aim of this investigation was to analyze zoster clinical evolution in 102 immunocompetent patients, subdivided by age (< 60 years and > or = 60 years) and sex, after treatment with acyclovir (4 g/die x 10 days). Signs and symptoms of the disease were evaluated, with particular attention to pain and the duration of post-herpetic neuralgia. Vescicular eruption was most frequently found in the thoraco-abdominal region and in the trigeminal one, with no significant differences among the subgroups. Two thirds of the subjects complained of pain and it was prevalent in female sex (84% of cases vs 53%, p < 0.01) but not in any age-class. After 1 months from the episode (and its pharmacological treatment), post-herpetic neuralgia was still present in about 20% of the patients, above all in those > or = 60 years; this last difference reached statistical significance after 6 months (9.7% vs 1.4% for subjects > or = 60 years and < 60 years respectively, p < 0.05). No patient showed any adverse pharmacological effect after treatment. We conclude that acyclovir is well accepted both in young and elderly immune-competent subjects suffering from HZ, but it necessitates further efficacy investigations in sight of its broader utilization.

Several diseases, and particularly cardiovascular affections, show a periodic fluctuation in their occurrence. We investigated acute myocardial infarction (AMI) incidence in connection with the day of the week, looking for a link with psycho-social phenomena. Eight hundred and fifty-two patients with AMI were considered: they had been admitted to the emergency department of two main towns of northeastern Italy during a calendar year. Eight hundred and seventeen (533 men, 284 women) were eligible for the purpose of this study. The time of symptom onset was recorded, cardiovascular risk factors and occupational condition were evaluated. All data were analyzed through chi-square test of uniformity and Halberg single cosinor test. No statistically significant difference from the uniform distribution appeared in acute events occurrence both in patients as a whole and in single subgroups subdivided according to gender and age. However, the preferential distribution during the days of the week was somewhat different between men (highest incidence at the extreme of the week) and women (highest incidence about mid-week). Statistically significant differences in AMI occurrence in the week were evidenced when patients were analyzed after subdivision according to their occupational condition: working subjects, in comparison with not-working individuals, showed a higher AMI incidence at the beginning of the week with respect to subsequent days. It is therefore likely that the stress associated with the return to work (according to the weekly working pattern of western society) represents an additional important cause of AMI. The mechanisms for that are only speculative.