Bidimensional SnSe2-Mesoporous Ordered Titania Heterostructures for Photocatalytically Activated Anti-Fingerprint Optically Transparent Layers

The design of functional coatings for touchscreens and haptic interfaces is of paramount importance for smartphones, tablets, and computers. Among the functional properties, the ability to suppress or eliminate fingerprints from specific surfaces is one of the most critical. We produced photoactivated anti-fingerprint coatings by embedding 2D-SnSe₂ nanoflakes in ordered mesoporous titania thin films. The SnSe₂ nanostructures were produced by solvent-assisted sonication employing 1-Methyl-2-pyrrolidinone. The combination of SnSe₂ and nanocrystalline anatase titania enables the formation of photoactivated heterostructures with an enhanced ability to remove fingerprints from their surface. These results were achieved through careful design of the heterostructure and controlled processing of the films by liquid phase deposition. The self-assembly process is unaffected by the addition of SnSe₂, and the titania mesoporous films keep their three-dimensional pore organization. The coating layers show high optical transparency and a homogeneous distribution of SnSe₂ within the matrix. An evaluation of photocatalytic activity was performed by observing the degradation of stearic acid and Rhodamine B layers deposited on the photoactive films as a function of radiation exposure time. FTIR and UV-Vis spectroscopies were used for the photodegradation tests. Additionally, infrared imaging was employed to assess the anti-fingerprinting property. The photodegradation process, following pseudo-first-order kinetics, shows a tremendous improvement over bare mesoporous titania films. Furthermore, exposure of the films to sunlight and UV light completely removes the fingerprints, opening the route to several self-cleaning applications.

Bidimensional Engineered Amorphous a-SnO2 Interfaces: Synthesis and Gas Sensing Response to H2S and Humidity

Two-dimensional (2D) transition metal dichalcogenides (TMDs) and metal chalcogenides (MCs), despite their excellent gas sensing properties, are subjected to spontaneous oxidation in ambient air, negatively affecting the sensor's signal reproducibility in the long run. Taking advantage of spontaneous oxidation, we synthesized fully amorphous a-SnO₂ 2D flakes (≈30 nm thick) by annealing in air 2D SnSe₂ for two weeks at temperatures below the crystallization temperature of SnO₂ (T < 280 °C). These engineered a-SnO₂ interfaces, preserving all the precursor's 2D surface-to-volume features, are stable in dry/wet air up to 250 °C, with excellent baseline and sensor's signal reproducibility to H₂S (400 ppb to 1.5 ppm) and humidity (10-80% relative humidity (RH)) at 100 °C for one year. Specifically, by combined density functional theory and ab initio molecular dynamics, we demonstrated that H₂S and H₂O compete by dissociative chemisorption over the same a-SnO₂ adsorption sites, disclosing the humidity cross-response to H₂S sensing. Tests confirmed that humidity decreases the baseline resistance, hampers the H₂S sensor's signal (i.e., relative response (RR) = R_a/R_g), and increases the limit of detection (LOD). At 1 ppm, the H₂S sensor's signal decreases from an RR of 2.4 ± 0.1 at 0% RH to 1.9 ± 0.1 at 80% RH, while the LOD increases from 210 to 380 ppb. Utilizing a suitable thermal treatment, here, we report an amorphization procedure that can be easily extended to a large variety of TMDs and MCs, opening extraordinary applications for 2D layered amorphous metal oxide gas sensors.

Improving the Photocatalytic Activity of Mesoporous Titania Films through the Formation of WS2/TiO2 Nano-Heterostructures

Heterostructures formed by anatase nanotitania and bidimensional semiconducting materials are expected to become the next-generation photocatalytic materials with an extended operating range and higher performances. The capability of fabricating optically transparent photocatalytic thin films is also a highly demanded technological issue, and increasing the performances of such devices would significantly impact several applications, from self-cleaning surfaces to photovoltaic systems. To improve the performances of such devices, WS₂/TiO₂ heterostructures obtained by incorporating two-dimensional transition metal dichalcogenides layers into titania mesoporous ordered thin films have been fabricated. The self-assembly process has been carefully controlled to avoid disruption of the order during film fabrication. WS₂ nanosheets of different sizes have been exfoliated by sonication and incorporated in the mesoporous films via one-pot processing. The WS₂ nanosheets result as well-dispersed within the titania anatase mesoporous film that retains a mesoporous ordered structure. An enhanced photocatalytic response due to an interparticle electron transfer effect has been observed. The structural characterization of the heterostructure has revealed a tight interplay between the matrix and nanosheets rather than a simple additive co-catalyst effect.

Chemical reactions on surfaces for applications in catalysis, gas sensing, adsorption-assisted desalination and Li-ion batteries: opportunities and challenges for surface science

The study of chemical processes on solid surfaces is a powerful tool to discover novel physicochemical concepts with direct implications for processes based on chemical reactions at surfaces, largely exploited by industry. Recent upgrades of experimental tools and computational capabilities, as well as the advent of two-dimensional materials, have opened new opportunities and challenges for surface science. In this Perspective, we highlight recent advances in application fields strictly connected to novel concepts emerging in surface science. Specifically, we show for selected case-study examples that surface oxidation can be unexpectedly beneficial for improving the efficiency in electrocatalysis (the hydrogen evolution reaction and oxygen evolution reaction) and photocatalysis, as well as in gas sensing. Moreover, we discuss the adsorption-assisted mechanism in membrane distillation for seawater desalination, as well as the use of surface-science tools in the study of Li-ion batteries. In all these applications, surface-science methodologies (both experimental and theoretical) have unveiled new physicochemical processes, whose efficiency can be further tuned by controlling surface phenomena, thus paving the way for a new era for the investigation of surfaces and interfaces of nanomaterials. In addition, we discuss the role of surface scientists in contemporary condensed matter physics, taking as case-study examples specific controversial debates concerning unexpected phenomena emerging in nanosheets of layered materials, solved by adopting a surface-science approach.

Sustainable Liquid-Phase Exfoliation of Layered Materials with Nontoxic Polarclean Solvent

Liquid-phase exfoliation is the most suitable platform for large-scale production of two-dimensional materials. One of the main open challenges is related to the quest of green and bioderived solvents to replace state-of-the-art dispersion media, which suffer several toxicity issues. Here, we demonstrate the suitability of methyl-5-(dimethylamino)-2-methyl-5-oxopentanoate (Rhodiasolv Polarclean) for sonication-assisted liquid-phase exfoliation of layered materials for the case-study examples of WS2, MoS2, and graphene. We performed a direct comparison, in the same processing conditions, with liquid-phase exfoliation using N-methyl-2-pyrrolidone (NMP) solvent. The amount of few-layer flakes (with thickness <5 nm) obtained with Polarclean is increased by ∼350% with respect to the case of liquid-phase exfoliation using NMP, maintaining comparable values of the average lateral size, which even reaches ∼10 μm for the case of graphene produced by exfoliation in Polarclean, and of the yield (∼40%). Correspondingly, the density of defects is reduced by 1 order of magnitude by Polarclean-assisted exfoliation, as evidenced by the I(D)/I(G) ratio in Raman spectra of graphene as low as 0.07 ± 0.01. Considering the various advantages of Polarclean over state-of-the-art solvents, including the absence of toxicity and its biodegradability, the validation of superior performances of Polarclean in liquid-phase exfoliation paves the way for sustainable large-scale production of nanosheets of layered materials and for extending their use in application fields to date inhibited by toxicity of solvents (e.g., agri-food industry and desalination), with a subsequent superb impact on the commercial potential of their technological applications.

Charge Redistribution Mechanisms in SnSe2 Surfaces Exposed to Oxidative and Humid Environments and Their Related Influence on Chemical Sensing

Tin diselenide (SnSe2) is a van der Waals semiconductor, which spontaneously forms a subnanometric SnO2 skin once exposed to air. Here, by means of surface-science spectroscopies and density functional theory, we have investigated the charge redistribution at the SnO2-SnSe2 heterojunction in both oxidative and humid environments. Explicitly, we find that the work function of the pristine SnSe2 surface increases by 0.23 and 0.40 eV upon exposure to O2 and air, respectively, with a charge transfer reaching 0.56 e-/SnO2 between the underlying SnSe2 and the SnO2 skin. Remarkably, both pristine SnSe2 and defective SnSe2 display chemical inertness toward water, in contrast to other metal chalcogenides. Conversely, the SnO2-SnSe2 interface formed upon surface oxidation is highly reactive toward water, with subsequent implications for SnSe2-based devices working in ambient humidity, including chemical sensors. Our findings also imply that recent reports on humidity sensing with SnSe2 should be reinterpreted, considering the pivotal role of the oxide skin in the interaction with water molecules.

Self-Assembled SnO2/SnSe2 Heterostructures: A Suitable Platform for Ultrasensitive NO2 and H2 Sensing

By means of experiments and theory, the gas-sensing properties of tin diselenide (SnSe₂) were elucidated. We discover that, while the stoichiometric single crystal is chemically inert even in air, the nonstoichiometric sample assumes a subnanometric SnO₂ surface oxide layer once exposed to ambient atmosphere. The presence of Se vacancies induces the formation of a metastable SeO₂-like layer, which is finally transformed into a SnO₂ skin. Remarkably, the self-assembled SnO₂/SnSe_2-x heterostructure is particularly efficient in gas sensing, whereas the stoichiometric SnSe₂ sample does not show sensing properties. Congruently with the theoretical model, direct sensing tests carried out on SnO₂/SnSe_2-x at an operational temperature of 150 °C provided sensitivities of (1.06 ± 0.03) and (0.43 ± 0.02) [ppm]^-1 for NO₂ and H₂, respectively, in dry air. The corresponding calculated limits of detection are (0.36 ± 0.01) and (3.6 ± 0.1) ppm for NO₂ and H₂, respectively. No detectable changes in gas-sensing performances are observed in a time period extended above six months. Our results pave the way for a novel generation of ambient-stable gas sensor based on self-assembled heterostructures formed taking advantage on the natural interaction of substoichiometric van der Waals semiconductors with air.

Personal solar ultraviolet radiation dosimetry in an occupational setting across Europe

BACKGROUND

Work-related solar ultraviolet radiation (UVR) is an important factor in the pathogenesis of non-melanoma skin cancer (NMSC). The World Health Organization, through the International Agency for Research on Cancer, has classified solar UVR as a group 1 carcinogen since 2012. The main problems encountered so far in the study of occupationally induced skin cancer include the lack of accurate occupational UVR dosimetry as well as insufficient distinction between occupational and leisure UVR exposure and underreporting of NMSC.

OBJECTIVES

The aim of this study was to collect long-term individual UVR measurements in outdoor workers across European countries.

METHODS

A prospective study was initiated through the European Academy of Dermatology and Venereology, Healthy Skin@Work Campaign, measuring UVR exposure doses at occupational settings of masons from five European countries. Measurements were performed for several consecutive months using the GENESIS-UV measurement system.

RESULTS

The results identified alarming UVR exposure data. Average daily UVR doses ranged 148.40-680.48 J/m² in Romania, 342.4-640.8 J/m² in Italy, 165.5-466.2 J/m² in Croatia, 41.8-473.8 J/m² in Denmark and 88.15-400.22 J/m² in Germany. Results showed an expected latitude dependence with increasing UVR yearly dosage from the north to the south of Europe.

CONCLUSIONS

This study shows that outdoor workers from EU countries included in this study are exposed to high levels of occupational solar UVR, vastly exceeding the occupational exposure limits for solar UVR exposure, considered to be 1-1.33 SED/day in the period from May to September. This finding may serve as an evidence-based recommendation to authorities on implementing occupational skin cancer prevention strategies.

Polycyclic Aromatic Hydrocarbons Exposure Assessment in a Refractory Brick Production

In a refractory brick manufacturing company a qualitative and quantitative determination of the sources of occupational exposure to polycyclic aromatic hydrocarbons (PAHs) was obtained in order to validate targeted hygiene measurements. The study included the assessment of PAHs contamination of work surfaces by wipe-sampling, cutaneous exposure by hand washing, contamination of personal protective equipments (gloves) by extraction in solvent, and airborne PAHs concentration in atmospheric samples. Biomonitoring was also carried out by measurement of urinary 1-hydroxypyrene (1-OHPU) in three groups of workers (packaging, production, and controls). The surface contamination sampling was performed in production, packaging, and in other departments (external area) in theory less contaminated by PAHs. Two different areas were identified within the production, one included surfaces that were regularly cleaned (A area) and one included data from non-cleaned surfaces (B area). To confirm the source of exposure, a clear correspondence was observed between the percentage of the single compounds in the binder and those measured in wipes and air samples. As far as the wipes are concerned, the concentrations of phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)pyrene (BaP), and the total PAHs mixture were higher in the B area than the A area of production. The same happened between the A area and the other two departments. According to results of the statistical analysis, these differences were significant. These results were confirmed by the hand washing data and the analysis of PPE. On the other hand, a marked difference does not exist between the packaging department and the external area. In air samples, the differences were much less evident with only higher concentrations of anthracene and total PAHs between production as a whole and the other two departments. Biological monitoring showed 1-OHPU values significantly higher in production workers than in packaging workers. In conclusion, the analysis of the wipes demonstrated that the production B area has a higher surface contamination compared to the production A area and the packaging department. In the absence of a significant difference in air concentrations of PAHs between A and B areas, this is attributable to surfaces not subject to cleaning. Results confirm that the measurement of surface contamination represents a valid tool for the assessment of sources of exposure to PAHs in the workplace.

Near Room Temperature Light-Activated WS2-Decorated rGO as NO2 Gas Sensor

The NO₂ response in the range of 200 ppb to 1 ppm of a chemoresistive WS₂-decorated rGO sensor has been investigated at operating temperatures of 25 °C and 50 °C in dry and humid air (40% RH) under dark and Purple Blue (PB) light conditions (λ = 430 nm). Few-layers WS₂, exfoliated by ball milling and sonication technique, with average dimensions of 200 nm, have been mixed with rGO flakes (average dimension 700 nm) to yield WS₂-decorated rGO, deposited on Si₃N₄ substrates, provided with platinum (30 μm gap distance) finger-type electrodes. TEM analysis showed the formation of homogeneous and well-dispersed WS₂ flakes distributed over a thin, continuous and uniform underlying layer of interconnected rGO flakes. XPS and STEM revealed a partial oxidation of WS₂ flakes leading to the formation of 18% amorphous WO₃ over the WS₂ flakes. PB-light irradiation and mild heating of the sensor at 50 °C substantially enhanced the baseline recovery yielding improved adsorption/desorption rates, with detection limit of 400 ppb NO₂ and reproducible gas responses. Cross sensitivity tests with humid air interfering vapor highlighted a negligible influence of water vapor on the NO₂ response. A charge carrier mechanism between WS₂ and rGO is proposed and discussed to explain the overall NO₂ and H₂O response of the WS₂-rGO hybrids.

Improved large-scale synthesis and characterization of small and medium generation PAMAM dendrimers

Dendrimers are promising polymers for biomedical applications; however, most dendrimer formulations have failed to move from laboratory science to upscaled products for preclinical testing or GMP production. This publications reports on an improved large-scale PAMAM dendrimer synthesis that is suitable to manufacture large amounts of highly pure and monodisperse dendrimers of generations G0–G5. Furthermore, an extended analytical guideline how to characterize PAMAM dendrimers with NMR, HPLC, SEC-MALS, ESI, MALDI, UV–vis, fluorescence, and IR spectroscopy is provided.

Probing DNA-stabilized fluorescent silver nanocluster spectral heterogeneity by time-correlated single photon counting

DNA-stabilized silver nanoclusters (DNA-AgNCs) are promising fluorophores whose photophysical properties and synthesis procedures have received increased attention in the literature. However, depending on the preparation conditions and the DNA sequence, the DNA-AgNC samples can host a range of different emitters, which can influence the reproducibility of the optical response and the evolution over time of the populations of these emitters. We have developed a simple method to characterize the spectral heterogeneity and time evolution of these emissive species at any given point in time after preparation, by plotting the average decay time as a function of emission wavelength. These so-called average decay time spectra were acquired for different excitation wavelengths of AgNCs stabilized by an oligonucleotide containing 24 cytosines (C24-AgNCs). The average decay time spectra allowed the comparison of sample preparation and the judgment of reproducibility. Therefore, we propose the use of the average decay time spectra as a robust and easy tool to characterize and compare different as-synthesized DNA-AgNC samples. The average decay time spectra can in general also be used to characterize the spectral heterogeneity of other fluorophores, such as luminescent colloidal nanoparticles, and to assess the reproducibility of a synthetic procedure containing an unknown distribution of emissive species.

Silicosis in Workers Exposed to Artificial Quartz Conglomerates: Does It Differ From Chronic Simple Silicosis?

Recently, a number of reports have been published on silicosis in workers exposed to artificial quartz conglomerates containing high levels of crystalline silica particles (70-90%) used in the construction of kitchen and bathroom surfaces. Three cases of silicosis in workers exposed to artificial quartz conglomerates are reported. The diagnosis was derived from both the International Labour Office and the International Classification of HRCT for Occupational and Environmental Respiratory Diseases (ICOERD) classifications and cytological analysis of bronchoalveolar lavage fluid. In 2 cases, levels of respirable silica greatly in excess of recommended standards were measured in the workplace, and cytological analysis of bronchoalveolar lavage fluid highlighted a prevalence of lymphocytes, meeting criteria for the diagnosis of accelerated silicosis. The prevention of pneumoconiosis caused by the use of innovative materials, such as artificial conglomerates with high crystalline silica content must be addressed.

[Incidental T1b-T3 gallbladder carcinoma. Extended cholecystectomy as an underestimated prognostic factor-results of the German registry]

BACKGROUND

The immediate radical re-resection (IRR) after simple cholecystectomy in incidental gallbladder carcinoma (IGBC) is debated in the literature. The German S3 guidelines recommend IRR in T2 and more advanced stages. Current literature recommends more extensive surgery even in T1b tumors.

METHODS

The German registry database was used for this study.

RESULTS

To date 883 cases of IGBC have been analyzed. In 8 out of 39 patients with a T1a tumor IRR was carried out as well as in 43 out of 109 patients with a T1b tumor. There was a significant survival benefit for re-resected T1b patients. There was also a significant survival benefit for the 215 T2 tumors and the 75 T3 patients with IRR compared to the 441 T2 tumors and 207 T3 tumors without IRR. Comparison of liver resection techniques showed good results for the wedge resection technique in T1b and T2 carcinomas. For T3 carcinomas more radical techniques showed better results. Less than 50 % of T2-3 tumors in the registry have been re-resection.

CONCLUSIONS

The IRR should be highly recommended in patients with T1b and more advanced IGBC. The wedge resection technique is an attractive procedure for T1b and T2 IGBC due to the lower invasiveness in spite of oncological adequacy.

[Dermatoses in the grocery industry]

Dermatological risks in supermarkets are largely comparable to those found in other workplaces such as food industry and trade in general Using two Pubmed search strings (one more specific, the other more sensitive) 11 papers were found (5 pertinent). The reasons for the little information may be the particular employment conditions that occur , in large-scale distribution. From this derives the difficulty in defining the epidemiology of skin diseases in the field and the need to refer to the literature on skin diseases in food handlers and cashiers. The most frequent dermatological disease in food handlers is irritant contact dermatitis, while the protein contact dermatitis seems to be more widespread than previously thought. Hand eczema together with nickel contact allergy is not rare in cashiers, but it can be difficult to assess if nickel allergy was occupationally acquired.

Nerve Growth Factor (NGF) up-regulation in the cerebrospinal fluid of newborns with myelomeningocele

BACKGROUND

Neurotrophic factors, such as Nerve Growth Factor (NGF), play a key role in the stimulation of sprouting, synaptic plasticity, and reorganization after spinal cord damage.

AIM

The aim of this study was to investigate the expression of nerve growth factor (NGF) in the cerebrospinal fluid (CSF) of newborns with myelomeningocele (MMC) and to determine its correlation with this spinal malformation.

PATIENTS AND METHODS

To measure the expression of NGF, we collected CSF samples of 14 newborns with MMC taken immediately before the neurosurgical correction of the spinal malformation and of 14 matched controls. Endogenous NGF levels were quantified using a two-site immuno-enzymatic assay. The statistical analysis was performed using the Mann-Whitney two-tailed two-sample test.

RESULTS

In the CSF of patients with MMC, NGF levels showed a significant increase compared to the mean levels of the control group (63.05 ± 7.3 vs 18.32 ± 4.5 pg/mL; (p < 0.001). No correlation was found between NGF expression and different types of MMC malformation, such as the level of spinal lesion and the association with Chiari II syndrome.

CONCLUSIONS

Our study shows an over-expression of NGF in the CSF of newborns with MMC. The observed pattern of NGF up-regulation in this subset of patients may stimulate axonal sprouting and synaptic reorganization of the damaged neural cells at the site of spinal cord injury, thereby representing an important biochemical marker of spinal cord damage in MMC patients.

Post-natal ultrasound morpho-dynamic evaluation of mild fetal hydronephrosis: a new management

BACKGROUND

Fetal hydronephrosis is the most common anomaly detected on antenatal ultrasound examination, affecting 1-5% pregnancies.

AIM

A new management in mild antenatal renal pelvis dilatation (ARPD), using a technique based on both morphological and dynamical evaluation.

MATERIALS AND METHODS

Prospective study conducted during a 36-months period in 180 consecutive newborns referred as having mild ARPD. Examinations consisted in a morphological ultra-sound (US) scan evaluating antero-posterior diameter, renal parenchyma, ureteral evidence and pelvis morphology and, subsequently, a dynamic evaluation to analyze any change of the urinary tract during bladder voiding. All children were evaluated both at 3rd day and 1 month after birth. They were divided among those with negative examinations and those with at least one positive scan, trying to discriminate within the latter, children suspected for transient pyelectasis from those suspected for organic pathology.

RESULTS

108 patients had normal US findings both at birth and at 1 month. The remaining 72 babies had at least one abnormal US examination: 54 were suspected for transient pyelectasis, while 18 suspected for organic pathology. At the end of the study, 61 babies (33.9%) had final diagnosis of transient pyelectasis and 11 cases (6.1%) of organic pathology. At one month the dynamic pattern of US findings had the highest negative predictive value, while renal parenchyma evaluation has the highest accuracy.

CONCLUSIONS

a dynamic US approach allowed to better select among infants suspected for transient pyelectasis from those suspected for organic pathology, avoiding unnecessary and invasive examinations in healthy babies.

Treatment of pressure sores in spina bifida patients with calcium alginate and foam dressings

STUDY DESIGN

Prospective study on local treatment of pressure sores using calcium alginate and foam dressings in spina bifida patients.

OBJECTIVE

Investigate if this sequential approach is valid and safe for selected patients with neurological impairments.

MATERIALS AND METHODS

Using European Pressure Ulcer Grading System, after clinical evaluation of local sore, selected patients of Spina Bifida Center of Rome were treated with sequential calcium alginate and foam dressings for 12 weeks. Pressure ulcere surfaces were measured monthly by ulcer tracing. The endpoints were the mean absolute areas surface reduction during every month and number of patients achieving a 50% or more during study.

RESULTS

14 patients (7 males aged 12-24 years) with spina bifida and pressure sores were treated. Mean and standard deviation of mean surface area reduction were 12.5 ± 7.5 cm 2 at start of the study versus 3.7 ± 5.2 cm 2 after 12 weeks, p < 0.001. 75% of the patients reached mean surface area reduction of 50% during trial. Dressing tolerance was good in every patient.

CONCLUSIONS

Calcium alginate and foam dressings are valid and safe approach in the treatment of pressure sores in selected patients with spina bifida. In fact, they protect the wound and create an environment favorable to healing.

Skin photoaging in farmers occupationally exposed to ultraviolet radiation

BACKGROUND

Most personal exposures to UV radiations occur from outdoor activities and several studies detected a significant association between skin cancer and outdoor occupation.

OBJECTIVE

The aim of the study was to ascertain the prevalence of photoaging signs in a population of Italian farmers and in a population of indoor workers taking account of confounding factors.

METHODS

169 farmers and 198 indoor workers were classified for skin phototype and for skin photoaging, moreover 13 variables were taken into account. Marginal permutation tests were adopted for statistical analysis.

RESULTS

Farmers were significantly older than the indoor workers. In workers occupationally exposed to UV photoaging increased with increasing age and years of occupational exposure to sunlight The distribution of skin phototype did not show significant differences in the two populations, while farmer showed a higher degree of photoaging than indoor workers.

CONCLUSIONS

Even if farmers were older than the in door workers it seems that outdoor work produces a higher degree of photoaging.

Vestibular evoked myogenic potentials in children affected by myelomeningocele

PURPOSE

The aim of the present study is to establish if the vestibular evoked myogenic potentials (VEMPs) could be used as a clinical test for the evaluation of vestibular function in children affected by myelomeningocele (MMC).

MATERIALS AND METHODS

Fifteen children, aged between 3 and 17 years, who had been affected by MMC were investigated. Data obtained from these children were compared with normal data from healthy children of the same age. Electromyographic activity of sternocleidomastoid muscle was recorded, while children were laid supine and asked to raise their head off the bed in order to activate their neck flexors bilaterally. The saccular receptors were acoustically stimulated with a logon of 500 Hz at an intensity of 130 dB peSPL presented monaurally through earphones. In each recording, we analyzed latencies and amplitudes of the p13-and n23 waves and the amplitude ratio between the two ears.

RESULTS

VEMPs were detected to be normal in 13 patients. In particular, the mean p13 and mean n23 latencies were 15.7 (±1.4) and 21.7 (±1.1) ms, respectively; the mean amplitude value was 84.7 (±36.6), while the mean amplitude ratio was 17.4 (±12). A comparison of latencies and amplitude ratios between the children and healthy control group did not reveal any significant difference. On the contrary, a comparison of amplitude values between the two groups showed significant differences.

CONCLUSION

In conclusion, vestibulocollic reflex is normal in patients affected by MMC, and VEMPs could represent a valid and noninvasive technique eligible to investigate the vestibular functions in these children.

[Dose and effect biomarkers in the diagnosis of asbestos-related diseases and health surveillance of exposed workers]

The aim of the study was to assess the reliability of the indicators of dose and effect in the health monitoring of asbestos exposed workers. In 49 cases out of 158 studied workers (31%) asbestos-related diseases were diagnosed following ATS criteria (2004). Using nonparametric statistical methods (permutation tests) 6 variables were analyzed with respect to asbestos-related diseases and working sectors, demonstrating a difference in the concentration of amphiboles (p < 0.01), greater in patients with asbestosis and workers involved in asbestos removal from railway carriages. There was not a correlation between mesothelin and amphiboles, chrysotile and total fibers concentrations (Spearman test).

[Prevention of occupational dermatitis in an international perspective]

Occupational dermatitis (OD) have always been a significant part of the occupational disease with huge social and economic costs. Traditionally, the standard program of OD prevention takes place in the three phases of protection, cleansing and use of emollient creams and other products able to improve the cutaneous trophism (skincare) at the end of the shiftwork. However, in countries like Germany where protection measures and skincare were widespread, there was not a simultaneous decrease in the OD. In recent years pilot programs for the prevention of OD have been implemented with positive results. In particular the integrated approach that includes three steps of primary, secondary and tertiary prevention (Osnabrueck model) is of great interest. Primary prevention is represented by introduction of technical regulations, pre-employment counselling and specific initiatives to promote health (healthy skin campaign). In the case of initial/minor OD, secondary prevention is accomplished through the dermatological treatment of the patient and 1-2 days outpatient education initiatives/skin protection training. In severe cases of individual OD, tertiary prevention involves the hospitalization of the patient in a dermatology department. In 2009 the European network EPOS (European Initiative for the Prevention of Occupational Skin Diseases) of preventive dermatology has been organized basing on the integrated approach of primary, secondary and tertiary prevention.

Development and validation of serum bilirubin nomogram to predict the absence of risk for severe hyperbilirubinaemia before discharge: a prospective, multicenter study

Background

Early discharge of healthy late preterm and full term newborn infants has become common practice because of the current social and economic necessities. Severe jaundice, and even kernicterus, has developed in some term infants discharged early. This study was designed to elaborate a percentile-based hour specific total serum bilirubin (TSB) nomogram and to assess its ability to predict the absence of risk for subsequent non physiologic severe hyperbilirubinaemia before discharge.

Methods

A percentile-based hour-specific nomogram for TSB values was performed using TSB data of 1708 healthy full term neonates. The nomogram's predictive ability was then prospectively assessed in five different first level neonatal units, using a single TSB value determined before discharge.

Results

The 75 ^th percentile of hour specific TSB nomogram allows to predict newborn babies without significant hyperbilirubinemia only after the first 72 hours of life. In the first 48 hours of life the observation of false negative results did not permit a safe discharge from the hospital.

Conclusion

The hour-specific TSB nomogram is able to predict all neonates without risk of non physiologic hyperbilirubinemia only after 48 to 72 hours of life. The combination of TSB determination and risk factors for hyperbilirubinemia could facilitate a safe discharge from the hospital and a targeted intervention and follow-up.

Determinants of bone mineral density, bone mineral content, and body composition in a cohort of healthy children: influence of sex, age, puberty, and physical activity

Interventions directed to the recognition of abnormal bone mineral density, bone mineral content, and body composition in the pediatric age require the definition of factors influencing bone mass acquisition during growth. We have evaluated in a cross-sectional manner by dual-energy X-ray absorptiometry the impact of sex, age, puberty, and physical activity on total body areal bone mineral density, regional (lumbar and femoral) bone mineral densities, bone mineral content, and body composition (fat mass and lean mass) in a cohort of 359 healthy Italian children aged 3-14 years and investigated their specific contribution to bone mass accrual. Statistical multiple regression analysis was performed dividing the population in pre- and post-pubertal groups. Bone mineral density at the lumbar spine has resulted equally distributed in both sexes before puberty while has resulted higher at the femoral necks in males at whatever age. A significant effect on bone mass acquisition was exerted by male sex and lean mass. In the areas where the cortical bone is prevalent, males of the pre-pubertal group have presented the highest values; in the areas where the cancellous bone is prevalent, both sexes were equivalent until the age of 9 years, but after this age, females have presented higher increases, probably related to the inferior dimensional development of lumbar vertebrae. Conclusively, male sex and lean mass seem to represent independent predictors of bone mass accrual in the cortical bone of the examined children, while female sex and pubertal maturation are independent predictors of bone mass accrual in the trabecular bone.

Laparoscopic sigmoid resection for diverticular disease has no advantages over open approach: midterm results of a randomized controlled trial

PURPOSE

Elective laparoscopic sigmoid resection (LSR) for symptomatic diverticular disease is supposed to have significant short-term advantages compared to open surgery (open sigmoid resection (OSR)). This opinion is rather based on inferences from trials on colonic resections for malignant diseases or minor laparoscopic surgery. This randomized controlled trial was conducted to compare quality of life as well as morbidity and clinical outcome after LSR vs. OSR following a midterm follow-up period.

METHODS

Patients presenting with a symptomatic sigmoid diverticular disease stage II/III (Stock/Hansen) were randomly allocated to LSR or OSR in a prospective multicenter trial. Endpoints included the quality of life assessed with a standardized questionnaire, postoperative mortality, and complications within the follow-up of 12 months after operation.

RESULTS

A total of 143 patients randomized between 2005 and 2008 in 12 centers could be analyzed. The recruitment was aborted for nonachievement of the planned sample size. Seventy-five patients were allocated to LSR, and 68 received OSR. Nine operations were converted to OSR (9%) and analyzed as intention to treat. Groups were comparable for age, gender, body mass index, comorbidity, and indication for surgery. Operation time was longer for LSR (p < 0.001). Quality of life did not differ between LSR and OSR, either during the early postoperative course or after 12 months (p = 0.172). Also, mortality and morbidity, including subgroups of major and minor morbidity, were compared.

CONCLUSION

LSR was not superior to OSR regarding postoperative quality of life and incidence of complications in this trial.

Neonatal outcome in hypertensive disorders of pregnancy

BACKGROUND

Hypertensive disorders in pregnancy account for increased perinatal morbidity and mortality when compared to uneventful gestations.

AIMS

To analyze perinatal outcome of pregnancies complicated by different kinds of hypertension to uncomplicated pregnancies in a series of Italian women and to compare our data with series from other countries.

STUDY DESIGN

The sample was divided into four groups of hypertensive women: chronic hypertension (CH), gestational hypertension (GH), preeclampsia (PE), and chronic hypertension complicated by preeclampsia (CHPE). One thousand normal pregnancies served as controls.

SUBJECTS

Neonatal features of the offspring of 965 Italian women with hypertension in pregnancy were evaluated.

MEASURES

Gestational age, birthweight and the rate of small for gestational age were the outcomes. Perinatal asphyxia and mortality were also assessed.

RESULTS

Gestational age, the mean of birth weight and birth percentile were significantly lower in all groups with hypertensive complications when compared with controls. The rate of very early preterm delivery (<32 weeks) was 7.8% in CH, 5.9% in GH, 21.2% in PE and 37.2% in CHPE while it was to 1.2% in the control group. The rate of SGA was globally 16.2% in CH, 22.8% in GH, 50.7% in PE, 37.2% in CHPE and 5% in controls. The rate of SGA in PE was much higher than reported in series from other countries.

CONCLUSION

Comparing our data with those reported from other countries, it is evident that the rate of fetal growth restriction in PE we found in our center, is significantly higher even in the presence of a global lower incidence of PE.

[Immediate radical re-resection of incidental T1b gallbladder cancer and the problem of an adequate extent of resection (results of the German Registry "Incidental Gallbladder Cancer")]

INTRODUCTION

Gallbladder cancer is suspected preoperatively in only 30 % of all patients, while the other 70 % of cases are discovered incidentally by the pathologist (incidental or occult gallbladder cancer or IGBC). If gallbladder cancer is suspected preoperatively, an open cholecystectomy must be performed. The increasing rate of cholecystectomies via laparoscopy has lad to the detection of more gallbladder cancers in an early stage. Extended resection with regional lymph node dissection for T2 carcinomas and for more advanced cancer has been suggested. If IGBC is detected postoperatively by the pathologist after simple cholecystectomy, radical re-resection in cases of T2 tumours and more advanced stages is recommended. However, it has been argued that T1b cancers may have spread regionally or systemically at presentation and, thus, it remains debatable whether T1b cancers should be treated by simple cholecystectomy or by radical resection. PATIENTS / MATERIAL AND METHOD: This investigation was based on the German Registry of "Incidental Gallbladder Cancer" of the German Society of Surgery. In the present study, we evaluated whether T1 carcinoma patients do profit from a radical re-resection and if the different techniques of liver resection have comparable results in T1 carcinomas.

RESULTS

We analysed 684 cases of IGBC including 124 patients with T1 cancer with a 5-year survival of 48 %. An extended re-resection increased the 5-year survival up to 68 % for T1-IGBC. The analysis shows no advantage for re-resection of T1a cancer. In contrast, the current analysis shows a statistically significant survival benefit for re-resection of T1b cancers from 34 % to 75 %. The Registry data show a trend of better survival for the patients treated with the wedge resection technique compared to other resection techniques.

CONCLUSION

For T1a cancer a simple cholecystectomy is sufficient. An immediate re-resection is highly recommended for patients with IGBC in T1b stage. The wedge resection technique combined with a locoregional lymphadenectomy of the hepatoduodenal ligament seems to be the strategy of choice for T1b cancer. An extended re-resection is necessary to determine the nodal status exactly, and to determine an exact definite staging for patients with T1b cancer.

[Asthma induced by chloramine T in nurses: case report]

BACKGROUND

Chloramine T is used in hospitals as a disinfectant and for sterilization of endoscopy instruments.

OBJECTIVES

A case of a nurse suffering from asthma due to Chloramine T is presented in order to focus attention on this occupational disease.

METHODS AND RESULTS

The patient (male, 43 years) had been a nurse since 1993, working in various departments and operating rooms where he was exposed to glutaraldehyde and Chloramine T to disinfect surgical and endoscopy instruments. In 2007 he noticed the beginning of asthmatic reactions after exposure to the disinfectant. Skin tests with common allergens gave positive reactions and a skin test with Chloramine T gave a positive result. An inhalation test with glutaraldehyde gave negative results for both asthma and rhinitis. During the inhalation test with Chloramine T 0.5%, a significant biphasic decrease in FEVI was observed. The score of subjective symptoms for rhinitis was negative,

CONCLUSIONS

The case confirms the current difficulty in diagnosing occupational asthma due to Chloramine T in health care workers, which is due to the frequent presence of late reactions and to exposure to several respiratory allergens and irritants in the workplace. The specific inhalation challenge is thus confirmed as the gold standard for the diagnosis of asthma induced by Chloramine T and in occupational asthma in general. It may very well be that the frequency of occupational asthma due to sensitization to Chloramine T in nurses is underestimated.