Risk factors for mental health disorders during the COVID-19 pandemic in Spain: A cohort study

Background

Data comparing the populations’ mental health from before, during and after the pandemic is needed. We aim to assess the risk factors for the first-onset and persistence of major depressive disorder (MDD) and suicidal thoughts and behaviours (STB) during the first year of the pandemic among the Spanish general population.

Methods

Cohort study through two online surveys from before the pandemic (N = 2,005, October/November 2019) and 12-months later (N = 1,357) on an adult Spanish, nationally representative, population-based sample. Multiple logistic regression models were used to assess the association between socio-demographic, COVID-19 related variables and healthcare received during the pandemic with the onset and persistence of MDD and STB.

Results

Women have more than 3-fold risk for the onset (OR 3.18; CI95% 1.40 -7.22) and persistence (OR 8.62; CI95% 1.74-42.48) of MDD. Studying and working at the same time (OR 10.13; CI95% 2.17-47.35) and having close relatives/friends with COVID-19 infection (OR 14.84; CI95% 1.91-115.18) or death (OR 5.26; CI95% 1.56-17.73) due to COVID-19 are risk factors for MDD onset. Sick-leave (OR 17.19; CI95% 2.65-112.56) and unemployment (OR 7.01; CI95% 1.85-26.43) increased the risk for MDD persistence. Death of friends/colleagues due to COVID-19 (OR 8.40; CI95% 1.47-48.07) increased the risk for STB onset, and being on sick-leave (OR 7.91; CI95% 1.80-34.66) for STB persistence.

Conclusions

During the COVID-19 pandemic, women were consistently more at risk of having worse mental health than men. Direct and indirect consequences caused or aggravated by the pandemic are common risk factors for the increased risk for the onset and persistence of both MDD and STB. Identification of high-risk subgroups and risk factors for MDD and STB among the Spanish general population will allow the developing and implementing of evidence-driven strategies for reducing the long-term impact of the pandemic in populations’ mental health.

Key messages

• The pandemic consequences, whether due to having had COVID-19, having close people affected or who have died from the infection and the social consequences increase the risk for worse mental health.

• Evidence-driven strategies for reducing the long-term impact of the pandemic in populations’ mental health should be a public health priority.

Influence of an external electric field on the rapid synthesis of MoO3 micro- and nanostructures by Joule heating of Mo wires

The growth mechanism of layered α-MoO₃ nano- and microplates on the surface of Mo wires during Joule heating has been investigated by application of an external electric field to the current carrying wire. The observed rapid growth of the structures, involving enhanced diffusion processes associated to the intense electric current, is further enhanced by the external field leading to a near instantaneous formation of MoO₃ plates. Thermally assisted electromigration in the Mo wire with the additional effect of the electric field appears as a very time effective method to grow MoO₃ layered low dimensional structures. Other molybdenum oxide nanostructures, such as nanospheres and nanocrystallites with different shapes, have been found to grow by deposition from the Mo wire on the electrodes used to apply the external electric field. The growth on the electrodes takes place by a thermally assisted electric-field-driven process.

Monascus spp. used in wheat kernel solid-state fermentations: growth, extrolite production and citrinin cytotoxicity

Monascus fermentation products can be consumed as food or feed supplements or used as food colouring or flavouring agents. In this study, qPCR and Q-TOF LC/MS methods were developed to monitor Monascus ruber and Monascus purpureus growth and extrolite (lovastatin, mevastatin, as well as the regulated mycotoxin, citrinin (CIT)) production, respectively. Wheat kernels were inoculated with one strain of each species during a solid-state fermentation followed over 63 days. Different growth and extrolite production patterns were clearly observed for the 2 tested strains. After 63 days, high lovastatin levels (up to 0.5 mg/g) were reached for M. ruber wheat fermented kernels while M. purpureus only yielded 0.1 mg/g of lovastatin at best, suggesting that M. ruber may be a better candidate for lovastatin production in a wheat-based model. Mevastatin levels were low and stable for both species. However, M. ruber fermented wheat kernels also contained the highest CIT content, up to 4.2 μg/g, i.e. at levels above the regulation threshold set by the European Union. CIT toxicity was then determined in vitro on bovine kidney cells, showing an IC10 of 6.10-4 M. At maximum concentrations encountered during solid-state fermentation, CIT toxicity was very low under chronic exposure.

Improving efficiency of viability-qPCR for selective detection of infectious HAV in food and water samples

AIM

To improve the efficacy of intercalating dyes to distinguishing between infectious and inactivated hepatitis A virus (HAV) in food.

METHODS AND RESULTS

Different intercalating dyes were evaluated for the discrimination between infectious and thermally inactivated HAV suspensions combining with the RT-qPCR proposed in the ISO 15216. Among them, PMAxx was the best dye in removing the RT-qPCR signal from inactivated HAV. Applied to lettuce and spinach, PMAxx-Triton pretreatment resulted in complete removal of the RT-qPCR signal from inactivated HAV. Likewise, this study demonstrates that this pretreatment is suitable for the discrimination of inactivated HAV in shellfish without further sample dilution. In mussels and oysters, the developed viability RT-qPCR method reduced the signal of inactivated HAV between 1·7 and 2·2 logs at high inoculation level, and signal was completely removed at low inoculation level.

CONCLUSIONS

This study showed that the use of PMAxx is an important improvement to assess HAV infectivity by RT-qPCR. It was shown that PMAxx-Triton pretreatment is suitable for the analysis of infectious HAV in complex food samples such as vegetables and shellfish.

SIGNIFICANCE AND IMPACT OF THE STUDY

The PMAxx-Triton pretreatment can be easily incorporated to the ISO norm for infectious virus detection.

Silicon surface passivation by PEDOT: PSS functionalized by SnO2 and TiO2 nanoparticles

In this paper, we present a study of silicon surface passivation based on the use of spin-coated hybrid composite layers. We investigate both undoped poly(3,4-ethylenedioxythiophene)/poly-(styrenesulfonate) (PEDOT:PSS), as well as PEDOT:PSS functionalized with semiconducting oxide nanomaterials (TiO₂ and SnO₂). The hybrid compound was deposited at room temperature by spin coating-a potentially lower cost, lower processing time and higher throughput alternative compared with the commonly used vacuum-based techniques. Photoluminescence imaging was used to characterize the electronic properties of the Si/PEDOT:PSS interface. Good surface passivation was achieved by PEDOT:PSS functionalized by semiconducting oxides. We show that control of the concentration of semiconducting oxide nanoparticles in the polymer is crucial in determining the passivation performance. A charge carrier lifetime of about 275 μs has been achieved when using SnO₂ nanoparticles at a concentration of 0.5 wt.% as a filler in the composite film. X-ray diffraction (XRD), scanning electron microscopy, high resolution transmission electron microscopy (HRTEM), energy dispersive x-ray in an SEM, and μ-Raman spectroscopy have been used for the morphological, chemical and structural characterization. Finally, a simple model of a photovoltaic device based on PEDOT:PSS functionalized with semiconducting oxide nanoparticles has been fabricated and electrically characterized.

3D and 2D growth of SnO2 nanostructures on Ga2O3 nanowires: synthesis and structural characterization

In this work, a simple thermal evaporation method has been used to obtain a variety of Ga₂O₃/SnO₂ nano-assemblies with different shapes and dimensionalities, which may affect their physical properties, especially those influenced by surface properties.

Continuous-flow system and monitoring tools for the dielectrophoretic integration of nanowires in light sensor arrays

Although nanowires (NWs) may improve the performance of many optoelectronic devices such as light emitters and photodetectors, the mass commercialization of these devices is limited by the difficult task of finding reliable and reproducible methods to integrate the NWs on foreign substrates. This work shows the fabrication of zinc oxide NWs photodetectors on conventional glass using transparent conductive electrodes to effectively integrate the NWs at specific locations by dielectrophoresis (DEP). The paper describes the careful preparation of NW dispersions by sedimentation and the dielectrophoretic alignment of NWs in a home-made system. This system includes an impedance technique for the assessment of the alignment quality in real time. Following this procedure, ultraviolet photodetectors based on the electrical contacts formed by the DEP process on the transparent electrodes are fabricated. This cost-effective mean of contacting NWs enables front-and back-illumination operation modes, the latter eliminating shadowing effects caused by the deposition of metals. The electro-optical characterization of the devices shows uniform responsivities in the order of 106 A W(-1) below 390 nm under both modes, as well as, time responses of a few seconds.

Study of mechanical resonances of Sb2O3 micro- and nanorods

Sb2O3 microrods with orthorhombic phase were grown by an evaporation-deposition method from a pure antimony source and substrate. The incorporation of Cr into the substrate has been found to enhance the growth of thinner rods with high crystalline quality, as is revealed by high resolution transmission electron microscopy (HRTEM). Electric field-induced mechanical resonances of Sb2O3 nanorods were studied by in situ measurements in a scanning electron microscope (SEM). Young's modulus of rods with different lengths and cross-sectional dimensions was calculated from the resonance frequency. The E values for the different rods were in the range of 16-48 GPa. For comparison, Young's moduli of several rods were also measured from the force-displacement curve recorded in an atomic force microscope (AFM). The slight difference between the E values obtained by the resonance and by the AFM techniques is within the accepted experimental error.

Conducting properties of nearly depleted ZnO nanowire UV sensors fabricated by dielectrophoresis

ZnO nanowires (NWs) with different radii (rNW) have been aligned between pre-patterned electrodes using dielectrophoresis (DEP) for the fabrication of high gain UV sensors. The DEP conditions (voltage amplitude and frequency) and electrode material, geometry and size were optimized to enhance the efficiency during the DEP process. To understand the alignment mechanism of the ZnO NWs, the dielectrophoretic force (FDEP) was analyzed as a function of the DEP conditions and NW dimensions. These studies showed that the DEP alignment process tends to trap NWs with a smaller radius. The effects of NW size on device performance were analyzed by means of I-V measurements in darkness and under illumination (200 nm < λ < 600 nm). In darkness, the NW resistance increases as rNW decreases due to the reduction of the conduction volume, until saturation is reached for rNW < 65 nm. On the other hand, the NW spectral photoresponse shows high values around 10(8) A W(-1) (measured at 5 V and λ < 370 nm) and follows a linear trend as a function of the NW cross section. In addition, the cut-off wavelength depends on rNW, presenting a clear blue-shift for NWs with a lower radius (rNW < 50 nm). Transient photoresponse studies show that NWs with lower radii have longer rise times and shorter decay times mainly due to surface trapping effects. Regardless of NW size, passivation of the surface using a dielectric capping layer of SiO2 reduces the dynamic range of the photoresponse due to a strong increase of the dark current.

Cathodoluminescence of rare earth implanted Ga2O3 and GeO2 nanostructures

Rare earth (RE) doped gallium oxide and germanium oxide micro- and nanostructures, mostly nanowires, have been obtained and their morphological and optical properties have been characterized. Undoped oxide micro- and nanostructures were grown by a thermal evaporation method and were subsequently doped with gadolinium or europium ions by ion implantation. No significant changes in the morphologies of the nanostructures were observed after ion implantation and thermal annealing. The luminescence emission properties have been studied with cathodoluminescence (CL) in a scanning electron microscope (SEM). Both β-Ga(2)O(3) and GeO(2) structures implanted with Eu show the characteristic red luminescence peak centered at around 610 nm, due to the (5)D(0)-(7)F(2) Eu(3+) intraionic transition. Sharpening of the luminescence peaks after thermal annealing is observed in Eu implanted β-Ga(2)O(3), which is assigned to the lattice recovery. Gd(3+) as-implanted samples do not show rare earth related luminescence. After annealing, optical activation of Gd(3+) is obtained in both matrices and a sharp ultraviolet peak centered at around 315 nm, associated with the Gd(3+) (6)P(7/2)-(8)S(7/2) intraionic transition, is observed. The influence of the Gd ion implantation and the annealing temperature on the gallium oxide broad intrinsic defect band has been analyzed.

Gallium-assisted growth of silicon nanowires by electron cyclotron resonance plasmas

The use of gallium droplets for growing Si nanowires (SiNWs) by electron cyclotron resonance plasmas is investigated. First, the relationship between evaporation time and resultant size of the gallium droplets is studied. Through the use of spectroscopic ellipsometry, the dependence of the surface plasmon resonance (SPR) energy on the droplet size is determined. From these gallium droplets, SiNWs were grown at 300 and 550 °C in electron cyclotron resonance plasmas containing SiH(4), Ar, and H(2). Scanning electron microscopy results show that tapered NWs are obtained for a wide range of growth conditions. Besides, it is found that H(2) plays an important role in the parasitic axial growth of the SiNWs. Namely, H(2) inhibits the radial growth and contributes dramatically to increasing the SiNW defects.

Voids, nanochannels and formation of nanotubes with mobile Sn fillings in Sn doped ZnO nanorods

ZnO nanorods containing different hollow structures have been grown by a thermal evaporation-deposition method with a mixture of ZnS and SnO(2) powders as precursor. Transmission electron microscopy shows rods with rows of voids as well as rods with empty channels along the growth axis. The presence of Sn nanoprecipitates associated with the empty regions indicates, in addition, that these are generated by diffusion processes during growth, probably due to an inhomogeneous distribution of Sn. The mechanism of forming voids and precipitates appears to be based on diffusion processes similar to the Kirkendall effect, which can lead to void formation at interfaces of bulk materials or in core-shell nanostructures. In some cases the nanorods are ZnO tubes partially filled with Sn that has been found to melt and expand by heating the nanotubes under the microscope electron beam. Such metal-semiconductor nanostructures have potential applications as thermal nanosensors or as electrical nanocomponents.

Growth and cathodoluminescence of Eu doped ZnO nanoneedles and branched nanoneedle structures

Rare-earth (RE) ions are widely investigated luminescent centers because their intraionic-4f transitions generate narrow and intense emission lines. In this work Eu doped ZnO nanoneedles have been grown, by a thermal evaporation-deposition method, and structural and luminescence characterization has been carried out. Mixtures of ZnO and Eu2O3 or of ZnS and Eu2O3 powders were used as precursors. Annealing of the compacted powder mixtures leads to the growth of nanoneedles and nanoneedle networks, as well as rods. EDS and CL measurements enable to detect the incorporation of Eu in these structures. The choice of precursor, ZnO-Eu2O3 or ZnS-Eu2O3 influences the morphology as well as the luminescence properties of the obtained nanostructures. In particular, while in the samples obtained from ZnO, the defect green luminescence band is practically absent, the band is present in the ZnO nanoneedles obtained from ZnS. Besides the broad deep level band, a series of well-separated narrow-peaks characteristic of the intrinsic red luminescence of Eu+3 ions are observed in all cases, whose relative intensities vary from one set of samples to the other. The results suggest that the Eu3+ ions have at least, two possible configurations in the ZnO lattice with different symmetry in the nanoneedles.

Europium doped gallium oxide nanostructures for room temperature luminescent photonic devices

Cathodoluminescence and photoluminescence techniques have been used to investigate room temperature light emission from beta-Ga(2)O(3):Eu nanostructures, which were obtained by two methods. In one of them, a mixture of Ga(2)O(3)/Eu(2)O(3) powders was used as precursor material and annealed under an argon flow. In the other one, undoped beta-Ga(2)O(3) nanostructures were first obtained by thermal oxidation of metallic gallium and europium was subsequently incorporated by a diffusion process. Room temperature luminescence at 610 nm due to Eu(3+) intraionic transitions from beta-Ga(2)O(3):Eu has been observed. Waveguiding of this red emitted light through the structures was shown.

Electrical properties of nanostructured tin oxide surfaces produced by thermal treatments

Sintering SnO2 powder in air or under an oxygen atmosphere at different temperatures, leads to polycrystalline samples with nanostructured surface as revealed by atomic force microscopy (AFM). The thermal treatments are also responsible for the variation of the surface electrical properties, as studied by scanning spreading resistance microscopy (SSRM) and scanning tunnelling microscopy and spectroscopy (STM-STS). The surface presents a p-conductance, contrary to the n-type characteristic of the bulk, and a band gap lower than the bulk band gap (3.6 eV). The electrical behaviour at the grain boundaries and the role of oxygen are discussed. X-ray photoelectron spectroscopy (XPS) results show a higher presence of oxygen at the boundaries, which generates a shift of the Fermi level position (E(F)-E(V)) towards lower energies.

Growth and luminescence of N doped TiO2 nanowires

Titanium oxide nanowires have been grown by thermal treatment of pressed TiN powder under argon or N2 flow. It has been found that two-step treatments at two different temperatures, 400 degrees C and 800 degrees C, lead to the growth of nanowires all over the sample surface. The nanowires are of single crystalline rutile structure. Energy dispersive X-ray spectroscopy and photoelectron spectroscopy measurements show that the oxide nanostructures contain N from the starting nitride. The mechanism of N incorporation into the oxide and its possible effect on the luminescence are discussed.

Sn doped GeO(2) nanowires with waveguiding behavior

Sn doped GeO(2) nanowires and microwires have been grown by an evaporation-deposition method, using a mixture of Ge and SnO(2) powders as precursors. Comparison with undoped GeO(2) nanowires grown by the same method shows that the presence of Sn prevents the formation of sharp bends, which makes the wires more suitable for waveguiding applications. Incorporation of about 0.5 at.% of Sn into the wires influences their morphology and gives rise to wires showing two different cross-sectional dimensions along the growth axis. Sn does not influence the luminescence spectra in the visible range but causes the appearance of emission bands in the near-infrared range. The waveguiding behavior of the Sn doped wires for green and red laser light has been demonstrated.

Cathodoluminescence study of semiconductor oxide micro- and nanostructures grown by vapor deposition

Nano- and microstructures of SnO(2), In(2)O(3) and ZnO have been grown during thermal treatment of compacted powders under argon flow. Indium-doped SnO(2) tube-shaped structures with rectangular cross-section are obtained by adding a fraction of In(2)O(3) to the starting SnO(2) powder. In-rich nanoislands were found to grow on some edges of the tubes. ZnO nanostructures doped with Sn or Eu were grown by adding SnO(2) and Eu(2)O(3) powder, respectively, to the ZnO precursor powder. All the samples have been characterized by the emissive and cathodoluminescence (CL) modes of scanning electron microscopy. CL images from SnO(2):In and In(2)O(3):Sn tubes and islands show a higher emission from the Sn-rich structures related to oxygen deficiency. CL of doped ZnO enables to detect the presence of dopant in specific regions or structures. CL appears to be a useful technique to study optical and electronic properties of semiconductor oxide nanostructures.

Visible cathodoluminescence of Er ions in β-Ga(2)O(3) nanowires and microwires

Erbium doped β-Ga(2)O(3) nanowires and microwires have been obtained by a vapour-solid process from an initial mixture of Ga(2)O(3) and Er(2)O(3) powders. X-ray diffraction (XRD) analysis reveals the presence of erbium gallium garnet as well as β-Ga(2)O(3) phases in the microwires. Scanning electron microscopy (SEM) images show that the larger microwires have a nearly rectangular cross-section. Transmission electron microscopy (TEM) and high-resolution TEM (HRTEM) analysis show good crystal quality of the β-Ga(2)O(3) nanowires. The nanostructures have been studied by means of the cathodoluminescence technique in the scanning electron microscope. Er intraionic blue, green and red emission lines are observed in luminescence spectra even at room temperature, which confirms the optical activity of the rare earth ions in the grown structures. Mapping of the main 555 nm emission intensity shows a non-homogeneous distribution of Er ions in the microstructures.

Formation and luminescence of nanoterraces and elongated structures in sintered TiO2

Samples of rutile TiO2 have been prepared by sintering compacted powders under argon flow. Long (above 20 h) sintering times at 1500 °C led to the formation of rods with squared cross-sections in a broad range of sizes. A two-step annealing treatment, at two temperatures, was found to favour the growth of low-dimensional elongated structures as well as a terraced structure on the grain surface, producing samples with high surface to volume ratio. The cathodoluminescence (CL) spectrum of the initial powder, shows an emission centred at about 2.40 eV, which can be separated into three Gaussian bands at 2.19, 2.30 and 2.55 eV. The main features of the CL spectra of sintered samples are an infrared band at 1.52 eV and a complex band in the visible range, whose peak position shifts with the annealing temperature. In samples sintered for 30 h an emission at 1.80 eV appears, while the dominant emission at 1.52 eV, due to titanium interstitials, is quenched.

Effects of capsule endoscopy on cardiac pacemakers

BACKGROUND AND STUDY AIMS

Capsule endoscopy is a new, noninvasive diagnostic technique which enables visualization of the mucosa of the small intestine in physiological conditions and without the need to subject the patient to external radiation. Wireless capsule video endoscopy is contraindicated in patients with a cardiac pacemaker. However, on the basis of the characteristics of the radiofrequency band used by the endoscopic capsule, together with a series of other factors, it is possible that the patient's use of a pacemaker should not be a contraindication to capsule endoscopy.

PATIENTS AND METHODS

This work had two phases: an in vitro study, using an interference detector, and an in vivo study involving 20 patients with cardiac pacemakers who showed symptoms or signs that justified a capsule endoscopy investigation.

RESULTS

No interference was observed during the first, in vitro, phase of the study. In the second phase, patients wore a Holter recorder for a mean time of 10 hours, during which the average number of recorded QRS complexes exceeded 30,000. All the pacemakers functioned normally. Interference due only to myopotentials was detected in a single patient in whom modification of the pacemaker programming was necessary. In the other 19 patients, neither sensing nor stimulation failures were observed.

CONCLUSIONS

No interference between the pacemaker and the endoscopic capsule was observed. All the pacemakers functioned normally, and no increased incidence of adverse effects was observed. Neither was any pacemaker-induced interference observed on the capsule endoscopy images.

Validation of the Coulter LH 750 in a hospital reference laboratory

Validation of the Coulter LH 750 was carried out in our central hospital laboratory, which processes 1500 hemograms per day for patients admitted into the 4 hospitals of our hospital complex and their corresponding outpatient departments. It is the reference laboratory for the provincial health care area. The analytical quality and the practical use of the instrument were studied, and we obtained within- and between-run imprecision estimates with reference controls of between 0.24% and 2.56% and inaccuracies of between -1.32% and 3.07% for basic hemogram parameters. Similar results were obtained with specimens from patients, with imprecision estimates between 0.56% and 2.56%. Linearity estimates were between 0.3 x 10(9)/L and 380 x 10(9)/L for leukocytes and between 3 x 10(9)/L and 1900 x 10(9)/L for platelets. The instrument evaluation was completed with a study of interference by bilirubin, lipemia, hemolysis, platelet clumps, and heparin and an examination of other variables, including carryover, detection limits, and the correlation of results with those of the Coulter Gen-S. A special evaluation was made of the new erythroblast count feature; with reference controls, imprecision estimates for this count were 10% to 12%, and with patient specimens imprecision averaged 10.39% up to 4 erythroblasts per 100 leukocytes. We also studied the correlation of LH 750 results and interferences with those of the manual reference method. Finally, National Committee for Clinical Laboratory Standards protocols were used to test for suspect and confirmation flags in leukocyte differential counts for 258 specimens representative of our routine. The practicability of the analyzer was studied in terms of technical difficulty, speed, and cost; also evaluated were new software elements for validation by source clinic and pathology and for reference values based on age. In conclusion, we analyzed the impact and improvements that may be expected in our laboratory (a user of Technicon and Coulter instruments) from introducing the new LH 750 analyzer into our routine.

Low-dose high-resolution CT of the chest in children and young adults: dose, cooperation, artifact incidence, and image quality

OBJECTIVE

The radiation dose, artifact incidence, and image quality of high-resolution chest CT examinations performed with standard and low doses and patient cooperation were investigated in children and young adults.

SUBJECTS AND METHODS

Three successive controlled studies were conducted in different groups of children and young adults, totaling 203 patients. Dosimetry of high-resolution CT was performed at 180, 50, and 34 mAs in three groups of 25 patients. Streak artifact incidence using alternating 50- and 34-mAs slices was assessed and correlated with patient compliance with breath-holding commands in 44 children. Image quality was evaluated in scans obtained with 34 versus 180 mAs in cooperative patients (n = 42) and in scans obtained with 50 versus 180 mAs in noncooperative patients (n = 42). Artifacts and image quality were assessed by controlled repeated interpretations.

RESULTS

Radiation dose was 5.4+/-1.6 mSv for 180 mAs, 1.5+/-0.5 mSv for 50 mAs, and 1.1+/-0.3 mSv for 34 mAs. Cooperation was obtained in 66% of the patients. Artifacts were more frequently seen in scans of noncooperative patients (30%) and in 34-mAs scans (47%); the highest incidence was found using 34 mAs in noncooperative patients (60%, p = 0.02). No differences in image quality scores were seen in scans obtained with 50 mAs versus those obtained with 180 mAs in noncooperative patients (p<0.05), and small differences were found in scans obtained with 34 mAs versus those obtained with 180 mAs in cooperative patients for fissures (p = 0.005) and peripheral structures (p = 0.02).

CONCLUSION

Low-dose high-resolution CT provided a significant reduction in radiation dose (72% for 50 mAs and 80% for 34 mAs) and good-quality images of the lung when performed with 50 mAs in noncooperative and 34 mAs in cooperative pediatric and young adult patients.

The RETAIN project: DICOM teleradiology over an ATM-based network. Radiological Examinations Transfer on an ATM Integrated Network

The RETAIN project (Radiological Examinations Transfer on an ATM Integrated Network) has aimed at testing videoconferencing and DICOM image transfers to get advice about difficult radiological cases over an asynchronous transfer mode (ATM)-based network, which affords a more comfortable interface than narrow-band networks and allows exchange of complete image series using the DICOM format of studies. For this purpose, an experimental ATM network was applied between six university hospitals in four different countries. An assessment of the functionalities of the system was performed by means of log-file analysis, video recording of the sessions and forms filled out by the participants at the end of each session. Questionnaires were answered by the users at the end of the project to bring out perspectives of utilisation and added value. We discussed 43 cases during 20 sessions. For technical or organisational problems, only 20 of the 36 planned sessions took place. The throughput over ATM (10.5 Mbit/s, 20 times faster than six ISDN B-channels) was adequate. Despite the experimental configuration of the network, the system was considered as satisfactory by all the physicians. In 72 % of the sessions, the expected result (answer to the question) was gained. By common consent, videoconferencing was unanimously regarded as a prominent tool in improving the interaction quality. Asynchronous transfer mode is an efficient method for fast transferring of radiologic examinations in DICOM format and for discussing them through high-quality videoconferencing.

Cervicothoracic lesions in infants and children

Cervicothoracic lesions are not uncommon in children. All cervicothoracic lesions except superficial lesions extend from the neck to the thorax through the thoracic inlet. Evaluation of this area involves multiple imaging modalities: plain radiography, ultrasonography, nuclear medicine, computed tomography, and magnetic resonance (MR) imaging. However, MR imaging is the method of choice for assessing the full extents of cervicothoracic lesions and their relationships to neurovascular structures. Cervicothoracic lesions can be classified as congenital lesions, inflammatory lesions, benign tumors, malignant tumors, and traumatic lesions. Lymphangioma is the most common cervicothoracic mass in children; other congenital lesions include hemangioma, thymic cyst, and vascular anomalies. Inflammatory adenopathy reactive to tuberculosis, mononucleosis, tularemia, cat-scratch fever, infection with human immunodeficiency virus, or other upper respiratory tract infections can manifest as cervicothoracic lesions; tuberculous abscesses and abscesses of other origins can also be seen. Lipoma, lipoblastoma, aggressive fibromatosis, and nerve sheath tumors (either isolated lesions or those associated with neurofibromatosis) can also occur as cervicothoracic masses. Malignant cervicothoracic tumors include lymphoma, thyroid carcinoma, neuroblastoma, and chest wall tumors (rhabdomyosarcoma, Ewing sarcoma, and neuroectodermal tumor). Traumatic cervicothoracic lesions include pneumomediastinum of traumatic origin, traumatic pharyngeal pseudodiverticulum, esophageal foreign-body granuloma, and cervicothoracic hematoma.

[Test of a teleradiology network based on ATM (asynchronous transfer mode)]

The retain project (Radiological Examination Transfer on ATM Integrated Network) consisted in teleradiology trials focused on pediatric imaging between two university hospitals. Rennes (France) and Barcelona (Spain) using an integrated broadband communication network based on ATM (asynchronous transfer mode), as part of a European research program. The network used was a full 10 Mbits/s ATM network directly connected to local PACSs (medical imaging hospital networks). One important reason to explicitly consider ATM for medical imaging is that multimedia applications on such networks allow integration of digital data and person-to-person communication. The utility of broadband communication for teleradiology has been confirmed. High quality video and sound are important for both human communication and medical video transfer. The project led to guidelines regarding technical options still open to improvement.

Worklists, preloading and archiving strategies; 3 years of clinical experience in the Barcelona PACS

We present data on 3 years of clinical experience using PACS involving developments on worklists, preloading and archiving strategies in a teaching paediatric hospital with all modalities connected to a commercial PACS. A method allowing generation of and handling of different worklists for computed radiography examinations has been developed in our centre. Worklists and archiving strategies are presented and discussed. We conclude that, with adequate worklists and efficient preloading implementation, current PACS could be used successfully in several clinical settings of a multimodality department.

Data interface between a radiology information system and a computed radiography system using a personal computer and standard software

We describe the implementation of a simple data interface between a radiology information system and a computed radiography system that uses personal computers and standard software. The radiology information system was developed in house and runs in a local area network of personal computers. The computed radiography system is connected to a picture archiving and communication system. We have implemented a software data interface on a microcomputer, allowing automated transfer of patient data from the radiology information system program to the computed radiography scheduling program. The interface adds essential information used by the picture archiving and communication system to handle work lists, routing, and archiving algorithms. We have improved the user interface, shortened the scheduling time, enabled coherence of data bases, and eased the use of computed radiography and examination routing in the picture archiving and communication system. We have been using this interface for more than 1 year without difficulties. This custom solution addresses the problem of interconnecting existing equipment, avoiding proprietary restrictions or the lack of effective standards. This approach can be applied to any radiology environment that uses personal computers.

[Resistance to antivitamins K]

Resistance to oral anticoagulant is a rare phenomenon. We report the case of a 32-year-old woman who required anticoagulation due to a deep venous thrombosis. She gradually developed resistance to acenocumarol and warfarin. Although the HPLC (high performance liquid chromatography) method proved satisfactory acenocumarol levels in plasma, therapeutic anticoagulation was not achieved. The mechanisms of resistance are discussed.

Fatal mushroom poisoning in Barcelona, 1986-1988

In 1986-88, 46 poisonings (4 of which were fatal) caused by amatoxin mushroom were reported. The fatalities were males aged between 7 and 65 years. They all had gastrointestinal symptoms and three of the patients died of acute hepatic insufficiency. The fourth died as a result of an intestinal perforation. The clinical and pathological alterations are compared with the findings of other authors.

Arachnoid cysts with intracystic and subdural haematoma

Two cases of arachnoid cysts with acute intracystic and subdural haematomas are described. CT examination was performed in both cases, and showed a hyperdense expansion with thinning of the inner table of the skull. The different ways in which subdural haematomas associated with arachnoid cysts may be seen on CT are discussed.

Post-radiation cranial malignant fibrous histiocytoma studied by CT

A 37-year-old woman presented with a proven case of malignant fibrous histiocytoma of the skull. This is thought to be a rare complication of post-radiation to a chromophobe adenoma which was treated by radiotherapy nine years previously. The radiation dose given to the sella region after the removal of the chromophobe adenoma was 4500 cGy.

Hepatotoxic mushroom poisoning: diagnosis and management

Hepatotoxic mushroom poisoning (due to Amanita, Lepiota and Galerina species) may be considered as a real medical emergency, since an early diagnosis and immediate treatment are required for a successful outcome. In this review the physio-pathological features and the clinical picture of amatoxin poisonings are described as the basis for diagnosis and therapeutic decisions. The treatment schedule proposed is analyzed in some points: Symptomatic and supportive measures, toxin removal and extraction procedures, and the possibility of using antidotes. Some parameters with prognostic significance are commented on. Finally, the mortality rate and its evolution throughout the present century is also considered.