Fifteen Years of Iodine Prophylaxis in Italy: Results of a Nationwide Surveillance (Period 2015-2019)

CONTEXT

In 2005, a nationwide program of iodine prophylaxis on a voluntary basis was implemented in Italy by law. However, recent data on iodine status are lacking.

OBJECTIVE

The aim of this study was to evaluate efficiency, effectiveness, and possible adverse effects (increased occurrence of thyroid autoimmunity and hyperthyroidism) of the Italian iodine prophylaxis program.

METHODS

From 2015 to 2019, a nationwide survey was performed. The use of iodized salt was evaluated in a sample of 164 593 adults and in 998 school canteens. A sample of 4233 schoolchildren (aged 11-13 years) was recruited to assess urinary iodine concentration, prevalence of goiter, and thyroid hypoechogenicity on ultrasound, with the latter being an indirect indicator of thyroid autoimmunity. Neonatal TSH values of 197 677 infants screened in regions representative of Northern, Central, and Southern Italy were analyzed to investigate the percentage of TSH values >5.0 mIU/L. Data on methimazole prescriptions were analyzed as indirect indicators of new cases of hyperthyroidism.

RESULTS

The prevalence of the use of iodized salt was 71.5% in adult population and 78% in school canteens. A median urinary iodine concentration of 124 μg/L, a prevalence of goiter of 2.2%, and a prevalence of thyroid hypoechogenicity of 5.7% were observed in schoolchildren. The percentage of neonatal TSH values >5.0 mIU/L resulted still higher (5.1%) than the World Health Organization threshold of 3.0%, whereas the prescriptions of methimazole showed a reduction of 13.5%.

CONCLUSION

Fifteen years of iodine prophylaxis have led to iodine sufficiency in Italy, although there still is concern about iodine nutritional status during pregnancy.

Repeated oral administration of low doses of silver in mice: tissue distribution and effects on central nervous system

BACKGROUND

Widespread use of silver in its different forms raises concerns about potential adverse effects after ingestion, the main exposure route for humans. The aim of this study was to investigate in CD-1 (ICR) male mice the tissue distribution and in vivo effects of 4-week oral exposure to 0.25 and 1 mg Ag/kg bw 10 nm citrate coated silver nanoparticles (AgNPs) and 1 mg Ag/kg bw silver acetate (AgAc) at the end of treatment (EoT) and after 4 weeks of recovery.

RESULTS

There were no treatment-related clinical signs and mortality, and no significant effects on body and organ weights at the EoT and after recovery. Treatment-related changes in hematology and clinical chemistry were found after recovery, the most relevant being a dose-dependent lymphopenia and increased triglycerides in AgNP-treated mice, and increased levels of urea in all treated groups, associated with decreased albumin only in AgAc-treated mice. At the EoT the highest silver concentration determined by Triple Quadrupole ICP-MS analysis was found in the brain, followed by testis, liver, and spleen; much lower concentrations were present in the small intestine and kidney. Tissue silver concentrations were slightly higher after exposure to AgAc than AgNPs and dose dependent for AgNPs. After recovery silver was still present in the brain and testis, highlighting slow elimination. No histopathological changes and absence of silver staining by autometallography were observed in the organs of treated mice. At the EoT GFAP (astrocytes) immunoreactivity was significantly increased in the hippocampus of AgNP-treated mice in a dose-dependent manner and Iba1 (microglial cells) immunoreactivity was significantly increased in the cortex of 1 mg/kg bw AgNP-treated mice. After recovery, a significant reduction of Iba1 was observed in the cortex of all treated groups. TEM analysis of the hippocampus revealed splitting of basement membrane of the capillaries and swelling of astrocytic perivascular end-feet in 1 mg/kg bw AgNP- and AgAc-treated mice at the EoT.

CONCLUSIONS

Our study revealed accumulation and slow clearance of silver in the brain after oral administration of 10 nm AgNPs and AgAc at low doses in mice, associated with effects on glial cells and ultrastructural alterations of the Blood-Brain Barrier.

Serum proteomic profiling at diagnosis predicts clinical course, and need for intensification of treatment in inflammatory bowel disease

BACKGROUND

Success in personalized medicine in complex disease is critically dependent on biomarker discovery. We profiled serum proteins using a novel proximity extension assay [PEA] to identify diagnostic and prognostic biomarkers in inflammatory bowel disease [IBD].

METHODS

We conducted a prospective case-control study in an inception cohort of 552 patients [328 IBD, 224 non-IBD], profiling proteins recruited across six centres. Treatment escalation was characterized by the need for biological agents or surgery after initial disease remission. Nested leave-one-out cross-validation was used to examine the performance of diagnostic and prognostic proteins.

RESULTS

A total of 66 serum proteins differentiated IBD from symptomatic non-IBD controls, including matrix metallopeptidase-12 [MMP-12; Holm-adjusted p = 4.1 × 10-23] and oncostatin-M [OSM; p = 3.7 × 10-16]. Nine of these proteins are associated with cis-germline variation [59 independent single nucleotide polymorphisms]. Fifteen proteins, all members of tumour necrosis factor-independent pathways including interleukin-1 (IL-1) and OSM, predicted escalation, over a median follow-up of 518 [interquartile range 224-756] days. Nested cross-validation of the entire data set allowed characterization of five-protein models [96% comprising five core proteins ITGAV, EpCAM, IL18, SLAMF7 and IL8], which define a high-risk subgroup in IBD [hazard ratio 3.90, confidence interval: 2.43-6.26], or allowed distinct two- and three-protein models for ulcerative colitis and Crohn's disease respectively.

CONCLUSION

We have characterized a simple oligo-protein panel that has the potential to identify IBD from symptomatic controls and to predict future disease course. Further prospective work is required to validate our findings.

Determination of Total Silicon and SiO2 Particles Using an ICP-MS Based Analytical Platform for Toxicokinetic Studies of Synthetic Amorphous Silica

Synthetic amorphous silica (SAS), manufactured in pyrogenic or precipitated form, is a nanomaterial with a widespread use as food additive (E 551). Oral exposure to SAS results from its use in food and dietary supplements, pharmaceuticals and toothpaste. Recent evidence suggests that oral exposure to SAS may pose health risks and highlights the need to address the toxic potential of SAS as affected by the physicochemical characteristics of the different forms of SAS. For this aim, investigating SAS toxicokinetics is of crucial importance and an analytical strategy for such an undertaking is presented. The minimization of silicon background in tissues, control of contamination (including silicon release from equipment), high-throughput sample treatment, elimination of spectral interferences affecting inductively coupled plasma mass spectrometry (ICP-MS) silicon detection, and development of analytical quality control tools are the cornerstones of this strategy. A validated method combining sample digestion with silicon determination by reaction cell ICP-MS is presented. Silica particles are converted to soluble silicon by microwave dissolution with mixtures of HNO3, H2O2 and hydrofluoric acid (HF), whereas interference-free ICP-MS detection of total silicon is achieved by ion-molecule chemistry with limits of detection (LoDs) in the range 0.2-0.5 µg Si g-1 for most tissues. Deposition of particulate SiO2 in tissues is assessed by single particle ICP-MS.

Proficiency testing as a tool to assess quality of data: the experience of the EU Reference Laboratory for chemical elements in food of animal origin

Quality and reliability of analytical results are, in general, key issues for all laboratories but become a top priority for laboratories accredited according to ISO/IEC 17025:2005. In this international standard the proficiency testing (PT) is regarded as a means to assure the validity of results. Nowadays, the proved competence of laboratories is an essential requirement especially for that structures that are involved in the official controls aimed at ensuring the safety of EU food products and the public health. To guarantee the EU consumers, the Council and the Commission have designated 28 European Union Reference Laboratories (EURLs) for food and feed, whose main role is to contribute to the standardization of analytical methods and to the harmonization of performance among the EU National Reference Laboratories (NRLs) to reach a comparable level of quality in the analytical data among all Member States. With this aim, the organization of PTs is a task that each EURL has to accomplish. Over the last 15 years, the EURL for chemical elements in food of animal origin (EURL-CEFAO) have organized 32 PTs on determination of total As, Cd, Pb and total Hg in meat, milk, fish and offal for the benefit of its network of NRLs. Some specific aspects of this activity will be discussed (e.g. preparation and characterization of PT materials, statistical evaluation of data, follow-up actions). Finally, based on the EURL-CEFAO experience, it will be demonstrated that the participation into PTs on a regular basis can result in an improvement of the laboratory’s performance as well as in the harmonization of the results submitted by participants.