Effects of long-term vegan diet on breath composition

The composition of exhaled breath derives from an intricate combination of normal and abnormal physiological processes that are modified by the consumption of food and beverages, circadian rhythms, bacterial infections, and genetics as well as exposure to xenobiotics. This complexity, which results wide intra- and inter-individual variability and is further influenced by sampling conditions, hinders the identification of specific biomarkers and makes it difficult to differentiate between pathological and nominally healthy subjects. The identification of a "normal" breath composition and the relative influence of the aforementioned parameters would make breath analyses much faster for diagnostic applications. We thus compared, for the first time, the breath composition of age-matched volunteers following a vegan and a Mediterranean omnivorous diet in order to evaluate the impact of diet on breath composition. Mixed breath was collected from 38 nominally healthy volunteers who were asked to breathe into a two-liter handmade Nalophan bag. Exhalation flow rate and carbon dioxide values were monitored during breath sampling. An aliquot (100 mL) of breath was loaded into a sorbent tube (250 mg of Tenax GR, 60/80 mesh) before being analyzed by thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). Breath profiling using TD-GC-MS analysis identified five compounds (methanol, 1-propanol, pentane, hexane, and hexanal), thus enabling differentiation between samples collected from the different group members . Principal component analysis showed a clear separation between groups, suggesting that breath analysis could be used to study the influence of dietary habits in the fields of nutrition and metabolism. Surprisingly, one Italian woman and her brother showed extremely low breath isoprene levels (about 5 ppbv), despite their normal lipidic profile and respiratory data, such as flow rate and pCO2. Further investigations to reveal the reasons behind low isoprene levels in breath would help reveal the origin of isoprene in breath.

Biochemical and haemodynamic indicators of stress in truck drivers

In order to investigate the extent of stress reaction during driving, this study was carried out on truck drivers engaged in long distance work. For each driver, epinephrine, norepinephrine, and cortisol were measured in urine, and dynamic ECG and blood pressure were monitored. The excretion rates of catecholamines showed great individual differences in the size of variations related to driving conditions. Epinephrine excretion rates were particularly high when weather and traffic conditions were more stressful. A relationship was found between epinephrine urinary levels and state-anxiety scores. Urinary excretion of norepinephrine was generally increased at the end of the working day and while driving in fog. The pattern of cortisol was not affected by the stress related to driving. The highest mean heart rates were monitored during difficult traffic and bad weather conditions.

[Appendectomy without inversion of the stump. A valid alternative. Our experience in 690 cases]

The paper reports the Authors' ten year experience on simple ligation in appendicectomy. After having reviewed the various surgical procedures, the Authors report their clinical experience and, considering the good postoperative results with this method, regard this procedure as an alternative to the technique of ligation with inversion of the stump in appendicectomy.

Liver iron overload and desferrioxamine treatment of porphyria cutanea tarda

The aim of this paper is to evaluate invasive and non-invasive indices of iron store and compare the effectiveness of different ferrodepletive protocols in 150 patients with porphyria cutanea tarda (PCT). Iron removal was performed either by intensive phlebotomy (22 cases) or slow subcutaneous and high intravenous doses of desferrioxamine (18 and 5 cases, respectively), and several laboratory parameters were studied; among these, oligo-elements and urinary porphyrins (detected by HPLC) were taken into account before and after the treatments. Serum iron, transferrin saturation, ferritin (RIA) and nuclear magnetic resonance results were compared with invasive findings in order to detect the metal deposition in liver tissue (atomic absorption concentration, optic or electron-microscopic detection). Liver iron overload was observed in 95% of cases. Full normalization of the disease took place by all the treatments, even if it required slightly more time in the phlebotomy group. We may conclude that ferrodepletive treatments are highly effective in PCT and, considering the fact that siderosis and liver damage always accompany the disease, these treatments are proposed as first choice in such cases.