[Circadian rhythm of serum levo-carnitine: parameters]. / Ritmo circadiano della levo-carnitina sierica: parametri ritmometrici per programmare una eventuale cronoterapia.

OBJECTIVE: The present study investigates the circadian rhythm (CR) of levo-carnitine (L-c) in systemic venous blood, in order to detect rhythmometric parameters that can be used for programming an eventual chronoterapy with such a molecule. MATERIALS AND METHODS: The L-c CR was investigated in 10 clinically healthy subjects (5 M; 5 F; mean age: 26.02 +/- 1.11 yrs), who were diurnally active and nocturnally resting. Blood samples were taken at 06:00; 08:00; 12:00; 18:00; 20:00; 24:00, not juxtaposed to breakfast, lunch and dinner. The serum concentrations of L-c were assayed via a spectrophotometric method. RESULTS: A nychtohemeral variability in circulating levels of L-c was observed, with a peak in the afternoon. Such a intradiem variability was validated to have the properties of a significant CR (MESOR = 33.37 mumol/l with a SEM of 1.19 mumol/l; amplitude = 6.31 mumol/l with 95%CL ranging from 3.58 mumol/l to 9.69 mumol/l; acrophase at 15:52 h:min with 95%CL ranging from 13:28 h:min to 17:00 h:min). CONCLUSIONS: It is important to remark that the validation of a CR for the systemic serum levels of L-c was obtained in diurnally-active/nocturnally resting subjects. Such validated rhythmometric properties are parameters that can be used for programming an eventual chronotherapy, considering that the molecule L-c is used for treating its various types of primary and secondary deficiency.

[Relationship among VIP plasma levels, esophageal dysfunction, and microcirculation in systemic sclerosis]. / Rapporti fra livelli plasmatici di VIP, disfunzione esofagea e del microcircolo in corso di sclerosi sistemica.

BACKGROUND: Recent studies suggest that esophageal dysmotility occurring in systemic sclerosis might be caused by neurotransmitter levels decrease. The aim of the present study is to value VIP plasma levels, and to relate them with the pressure of the inferior esophageal sphincter (IES) and the capillaroscopy score in a group of patients affected by Systemic Sclerosis (SSc). METHODS: Eleven subjects affected by SSc (eight male and three female, age from 30 to 72 years old) have been studied through esophageal manometry, capillaroscopy and VIP plasma levels evaluation. Fifteen healthy volunteers, as control group, have been enlisted. RESULTS: Our results show a decrease of VIP plasma levels in patients with SSc compared with control group. The difference between two groups has statistical significance (p < 0.01). Capillaroscopy has shown remarkable microcirculatory impairment and the esophageal manometry proved a decreased IES pressure. The scores of capillaroscopy, VIP plasma levels and pressures of IES have been compared and it has been observed that there is a relationship between VIP plasma level and pressure of IES. CONCLUSIONS: VIP plasma levels decrease enhances the role of the autonomic disorder in SSc and may contribute to produce the alteration of vascular tone as well as the gastroenteric musculature dysfunction.