Monitoring low benzene exposure: comparative evaluation of urinary biomarkers, influence of cigarette smoking, and genetic polymorphisms.

Benzene is a human carcinogen and an ubiquitous environmental pollutant. Identification of specific and sensitive biological markers is critical for the definition of exposure to low benzene level and the evaluation of the health risk posed by this exposure. This investigation compared urinary trans,trans-muconic acid (t,t-MA), S-phenylmercapturic acid, and benzene (U-benzene) as biomarkers to assess benzene exposure and evaluated the influence of smoking and the genetic polymorphisms CYP2E1 (RsaI and DraI) and NADPH quinone oxidoreductase-1 on these indices. Gas station attendants, urban policemen, bus drivers, and two groups of controls were studied (415 subjects). Median benzene exposure was 61, 22, 21, 9 and 6 microg/m(3), respectively, with higher levels in workers than in controls. U-benzene, but not t,t-MA and S-phenylmercapturic acid, showed an exposure-related increase. All the biomarkers were strongly influenced by cigarette smoking, with values up to 8-fold higher in smokers compared with nonsmokers. Significant correlations of the biomarkers with each other and with urinary cotinine were found. A possible influence of genetic polymorphism of CYP2E1 (RsaI and/or DraI) on t,t-MA and U-benzene in subjects with a variant allele was found. Multiple linear regression analysis correlated the urinary markers with exposure, smoking status, and CYP2E1 (RsaI; R(2) up to 0.55 for U-benzene). In conclusion, in the range of investigated benzene levels (<478 micro/m(3) or <0.15 ppm), smoking may be regarded as the major source of benzene intake; among the study indices, U-benzene is the marker of choice for biomonitoring low-level occupational and environmental benzene exposure.     

Personality profile and allodynic migraine

Migraine is known to be associated to particular psychological features. Cutaneous allodynia is a painful sensation or discomfort induced by a non-noxious stimulus, and is a frequent complaint during migraine attacks. The aim of this study was to compare the personality profile of allodynic and non-allodynic migraineurs to identify possible relationships between psychological aspects and the presence of allodynia. The Symptom Check List 90-R (SCL90R), a 90-item self-report psychological symptom inventory, was used to investigate the psychological profile of our patients. The presence of allodynia was assessed by a set of semi-structured questions that investigated if the patient experienced abnormal scalp sensitiveness and/or discomfort during headache episodes. Twenty-five nonallodynic patients and 38 allodynic migraineurs were studied. No significant difference was found between the two groups in any area of the personality profile. The psychological profile seems not to affect the presence/absence of cutaneous allodynia in migraine patients. This reinforces the hypothesis that allodynia is a “somatic” symptom, not modified by psychological aspects.

     

A 7-year experience with low blood TSH cutoff levels for neonatal screening reveals an unsuspected frequency of congenital hypothyroidism (CH)

Context  The guidelines of the National Academy of Clinical Biochemistry advocated the use of low bloodspot TSH (b-TSH) threshold for newborn screening of congenital hypothyroidism (CH). The impact generated by the application of this indication is largely unknown.
Objective  To determine the impact on CH epidemiology and classification generated by the introduction of low b-TSH cutoff.
Design  Retrospective study of 629,042 newborns screened with b-TSH cutoffs of 12 (years 1999–2002) or 10 mU/l (2003–2005).
Measurements  Congenital hypothyroidism incidence and classification. Results were compared with those virtually obtained with the previous cutoff (20 mU/l). Clinical re-evaluation after L-T4 withdrawal of a representative group of 140 CH children at 3–5 years.
Results  Low b-TSH cutoffs allowed the detection of 435 newborns with confirmed CH (incidence 1:1446). Forty-five percent of CH infants, including 12/141 dysgenesis, would have been missed using the 20 mU/l cutoff. In contrast to current classification, 32% CH newborns had thyroid dysgenesis and 68% had a gland in situ (GIS). Premature birth was present in 20% of cases being associated with a 3–5 fold increased risk of GIS CH. Re-evaluation at 3–5 years showed a permanent thyroid dysfunction in 78% of 59 CH toddlers with GIS.
Conclusions  The use of low b-TSH cutoff allowed the detection of an unsuspected number of children with neonatal hypothyroidism, evolving in mild permanent thyroid dysfunction later in life. The incidence of CH in this Italian population appears to be double than previously thought with a clear-cut prevalence of functional defects over dysgenetic ones.     

Adherence to the traditional Mediterranean diet in a population of South of Italy: factors involved and proposal of an educational field-based survey tool

We developed and validated a tool assessing the adherence to the Mediterranean diet based on current nutritional recommendations for health promotion (MEDI-Quest). Four-hundred-and-eleven clinically healthy subjects completed both the MEDI-Quest-score and the validated MedDietScore (MDS). A good accordance between MEDI-Quest and MDS was observed (R?=?0.638), as well as for the percentage of individuals having similar scores with both methods for each food group. Regarding socio-cultural-factors, higher adherence was observed in people with older-age (OR?=?1.030, p?<?.0001), more qualifier-employment (OR?=?1.136, p?<?.005), higher-income (OR?=?1.925, p?<?.0001), interest in reading-food-labels (OR?=?2.057, p?<?.0001), and having frequent physical activity (OR?=?1.608, p?<?.05). In conclusion, our findings show that (1) the MEDI-Quest score well correlate with MDS, and (2) the adherence to the Mediterranean diet is not particularly high due to less cultural roots. It could be necessary to improve people’s knowledge about food and nutrition, taking into consideration believes embedded in their family, tradition and religion.     

A mucoadhesive polymer extracted from tamarind seed improves the intraocular penetration and efficacy of rufloxacin in topical treatment of experimental bacterial keratitis

Bacterial keratitis is a serious infectious ocular disease requiring prompt treatment to prevent frequent and severe visual disabilities. Standard treatment of bacterial keratitis includes topical administration of concentrated antibiotic solutions repeated at frequent intervals in order to reach sufficiently high drug levels in the corneal tissue to inhibit bacterial growth. However, this regimen has been associated with toxicity to the corneal epithelium and requires patient hospitalization. In the present study, a mucoadhesive polymer extracted from tamarind seeds was used for ocular delivery of 0.3% rufloxacin in the treatment of experimental Pseudomonas aeruginosa and Staphylococcus aureus keratitis in rabbits. The polysaccharide significantly increased the intra-aqueous penetration of rufloxacin in both infected and uninfected eyes. Rufloxacin delivered by the polysaccharide reduced P. aeruginosa and S. aureus in the cornea at a higher rate than that obtained by rufloxacin alone. In particular, use of the polysaccharide allowed a substantial reduction of S. aureus in the cornea to be achieved even when the time interval between drug administrations was extended. These results suggest that the tamarind seed polysaccharide prolongs the precorneal residence times of antibiotics and enhances drug accumulation in the cornea, probably by reducing the washout of topically administered drugs. The tamarind seed polysaccharide appears to be a promising candidate as a vehicle for the topical treatment of bacterial keratitis.