Release of Nanoparticles in the Environment and Catalytic Converters Ageing.

A Three-Way Catalyst (TWC) contains a cordierite ceramic monolith coated with a layer of Al2O3, CexZr1-xO2 and platinoids mixture. Under standard operation, the platinoid concentration decreases, exposing the remaining washcoat structure. After that particle release stage, the sintering process follows where the crystalline CexZr1-xO2 solution is broken and begins to separate into ZrO2 and CeO2 phases. ZrO2 is released to the environment as micro and nanoparticles, while a small amount of CeO2 generates a new AlxCe1-xO2 composite. The main effect of Ce capture is the growth in the size of the polycrystal structure from 86.13 ± 16.58 nm to 225.35 ± 69.51 nm. Moreover, a transformation of cordierite to mullite was identified by XRD analysis. Raman spectra showed that the oxygen vacancies (Vö) concentration decreased as CexZr1-xO2 phases separation occurred. The SEM-EDS revealed the incorporation of new spurious elements and microfractures favouring the detachment of the TWC support structure. The release of ultrafine particles is a consequence of catalytic devices overusing. The emission of refractory micro to nanocrystals to the atmosphere may represent an emerging public health issue underlining the importance of implementing strict worldwide regulations on regular TWCs replacement.

Effects of Untreated Drinking Water at Three Indigenous Yaqui Towns in Mexico: Insights from a Murine Model.

BACKGROUND: Reports in a northwestern Mexico state linked arsenic (As) in drinking water to DNA damage in people from indigenous communities. However, this correlation remains under discussion due to unknown variables related to nutrition, customs, and the potential presence of other metal(oid)s. METHODS: To determine this association, we sampled water from three Yaqui towns (Cócorit, Vícam, and Pótam), and analyzed the metals by ICP-OES. We exposed four separate groups, with five male CD-1 mice each, to provide further insight into the potential effects of untreated drinking water. RESULTS: The maximum concentrations of each metal(oid) in µg·L-1 were Sr(819) > Zn(135) > As(75) > Ba(57) > Mo(56) > Cu(17) > Al(14) > Mn(12) > Se(19). Histological studies revealed brain cells with angulation, satellitosis, and reactive gliosis with significant statistical correlation with Mn and As. Furthermore, the liver cells presented hepatocellular degeneration. Despite the early response, there is no occurrence of both statistical and significative changes in hematological parameters. CONCLUSIONS: The obtained results provide experimental insights to understand the potential effects of untreated water with low As and Mn contents in murine models. This fact is noteworthy because of the development of histological changes on both the brain and liver at subchronic exposure.

Clinical impact of preoperative tumour contact with superior mesenteric-portal vein in patients with resectable pancreatic head cancer.

INTRODUCTION: The NCCN classification of resectability in pancreatic head cancer does not consider preoperative radiological tumour ≤ 180° contact with portal vein/superior mesenteric vein (PV/SMV) as a negative prognostic feature. The aim of this study is to evaluate whether this factor is associated with higher rate of incomplete resection and poorer survival. METHODS: All patients considered for pancreatic resection between 2012 and 2017 at two Spanish referral centres were included. Patients with borderline and locally advanced pancreatic ductal adenocarcinoma (PDAC) according to NCCN classification were excluded. Preoperative CT scans were reviewed by dedicated radiologists to identify radiologic tumour contact with PV/SMV. RESULTS: Out of 302, 71 patients were finally included in this study. Twenty-two (31%) patients showed tumour-PV/SMV contact (group 1) and 49 (69%) did not show any contact (group 2). Patients in group 1 showed a statistically significantly higher rate of R1 and R1-direct margins compared with group 2 (95 vs 28% and 77 vs 10%) and lower median survival (24 vs 41 months, p = 0.02). Preoperative contact with PV/SMV, lymph node metastases, R1-direct margin and NO adjuvant chemotherapy were significantly associated with disease-specific survival at multivariate analysis. CONCLUSION: Preoperative radiological tumour contact with PV/SMV in patients with NCCN resectable PDAC is associated with high rate of pathologic positive margins following surgery and poorer survival.

Identification of refractory zirconia from catalytic converters in dust: An emerging pollutant in urban environments.

Using catalytic converters is one of the most effective methods to control vehicle emissions. A washcoat of cerium oxide-zirconia (CeO2-ZrO2) has been used to enhance the performance of the catalytic converter device. To date, the prevalence of this material in the environment has not been assessed. In this study, we present evidence of the existence of inhalable zirconia in urban dust. Samples of the washcoat, exhaust pipe, topsoil, and road dust were analyzed by X-ray fluorescence, X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, photoluminescence (PL) spectroscopy, and thermally stimulated luminescence (TSL). The results showed a CeO2-ZrO2 phase separation after sintering. This causes the emission of ZrO2, CeO2, and CeZrOx particles smaller than 1 µm, which can likely reach the alveolar macrophages in the lungs. The Ce-Zr content in road dust exceeds geogenic levels, and a significant correlation of 0.87 (p < 0.05) reflects a common anthropic source. Chronic exposure to such refractory particles may result in the development of non-occupational respiratory diseases. The inhalable crystalline compounds emitted by vehicles are a significant environmental health hazard, revealing the need for further investigation and assessment of zirconia levels generated by automobiles in urban areas worldwide.

Neuronal surface P antigen (NSPA) modulates postsynaptic NMDAR stability through ubiquitination of tyrosine phosphatase PTPMEG.

BACKGROUND: Cognitive dysfunction (CD) is common among patients with the autoimmune disease systemic lupus erythematosus (SLE). Anti-ribosomal P autoantibodies associate with this dysfunction and have neuropathogenic effects that are mediated by cross-reacting with neuronal surface P antigen (NSPA) protein. Elucidating the function of NSPA can then reveal CD pathogenic mechanisms and treatment opportunities. In the brain, NSPA somehow contributes to glutamatergic NMDA receptor (NMDAR) activity in synaptic plasticity and memory. Here we analyze the consequences of NSPA absence in KO mice considering its structural features shared with E3 ubiquitin ligases and the crucial role of ubiquitination in synaptic plasticity. RESULTS: Electrophysiological studies revealed a decreased long-term potentiation in CA3-CA1 and medial perforant pathway-dentate gyrus (MPP-DG) hippocampal circuits, reflecting glutamatergic synaptic plasticity impairment in NSPA-KO mice. The hippocampal dentate gyrus of these mice showed a lower number of Arc-positive cells indicative of decreased synaptic activity and also showed proliferation defects of neural progenitors underlying less adult neurogenesis. All this translates into poor spatial and recognition memory when NSPA is absent. A cell-based assay demonstrated ubiquitination of NSPA as a property of RBR-type E3 ligases, while biochemical analysis of synaptic regions disclosed the tyrosine phosphatase PTPMEG as a potential substrate. Mice lacking NSPA have increased levels of PTPMEG due to its reduced ubiquitination and proteasomal degradation, which correlated with lower levels of GluN2A and GluN2B NMDAR subunits only at postsynaptic densities (PSDs), indicating selective trafficking of these proteins out of PSDs. As both GluN2A and GluN2B interact with PTPMEG, tyrosine (Tyr) dephosphorylation likely drives their endocytic removal from the PSD. Actually, immunoblot analysis showed reduced phosphorylation of the GluN2B endocytic signal Tyr1472 in NSPA-KO mice. CONCLUSIONS: NSPA contributes to hippocampal plasticity and memory processes ensuring appropriate levels of adult neurogenesis and PSD-located NMDAR. PTPMEG qualifies as NSPA ubiquitination substrate that regulates Tyr phosphorylation-dependent NMDAR stability at PSDs. The NSPA/PTPMEG pathway emerges as a new regulator of glutamatergic transmission and plasticity and may provide mechanistic clues and therapeutic opportunities for anti-P-mediated pathogenicity in SLE, a still unmet need.

Identification of inhalable rutile and polycyclic aromatic hydrocarbons (PAHs) nanoparticles in the atmospheric dust.

Addressing the presence of rutile nanoparticles (NPs) in the air is a work in progress, and the development of methodologies for the identification of NPs in atmospheric dust is essential for the assessment of its toxicological effects. To address this issue, we selected the fast growing desertic city of Hermosillo in northern Mexico. Road dust (n = 266) and soils (n = 10) were sampled and bulk Ti-contents were tested by portable X-ray fluorescence. NPs were extracted from atmospheric dust by PM1.0-PTFE filters and further characterized by Confocal Raman Microscopy, Energy-dispersive X-ray spectroscopy (EDS) coupled to Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM). Results showed (i) the average concentration of Ti in road dust (3447 mg kg-1) was similar to natural values and worldwide urban dusts; (ii) the bulk geochemistry was not satisfactory for Ti-NPs identification; (iii) 76% of the total extracted PM1.0 sample corresponded to NPs; (iv) mono-microaggregates of rutile NPs were identified; (v) ubiquitous polycyclic aromatic hydrocarbons (PAHs) were linked to NPs. The genotoxicity of rutile and PAHs, in connection with NPs content, make us aware of a crucial emerging environmental issue of significant health concern, justifying further research in this field.

Metal bioaccessibility, particle size distribution and polydispersity of playground dust in synthetic lysosomal fluids.

Inhalation of playground dust-derived fine particles in schoolyards poses a risk from exposure to metal(oids) and minerals. In this work, we obtained the total concentration and bioaccessibility of metal(oids) with Gamble Solution (GS) and Artificial Lysosomal Fluid (ALF) synthetic solutions, simulating the extracellular neutral pH environment of the lung and the intracellular conditions of the macrophage, respectively. Scanning Electron Microscope (SEM), and Dynamic Light Scattering analysis (DLS) techniques were used to characterize particles with a size smaller than 2.5 µm, which can be assimilated by macrophages in the deep part of the lung. Arsenic (As), lead (Pb), copper (Cu), manganese (Mn), zinc (Zn), and iron (Fe) showed concentrations of 39.9, 147.9, 286, 1369, 2313, 112,457 mg·kg-1, respectively. The results indicated that all studied elements were enriched when compared to (i) local geochemical background and (ii) findings reported in other cities around the world. Bioaccessibility of metal(oids) in GS was low-moderate for most studied elements. However, in ALF assays, bioaccessibility was high among the samples: for lead (Pb = 34-100%), arsenic (As = 14.7-100%), copper (Cu = 17.9-100%), and zinc (Zn = 35-52%) possibly related to hydrophobic minerals in dust. SEM and DLS image analysis showed that playground dust particles smaller than 2.5 µm are dominant, particularly particles with a size range of 500-600 nm. The polydispersity detected in these particle sizes showed that most of them might be crystalline compounds (elongated shapes) forming agglomerates instead of combustion particles (spheres). Moreover, the circularity detected varies from 0.57 to 0.79 (low roundness), which corroborates this finding. The presence of agglomerates of ultrafine/nanoparticles containing highly bioaccessible metals in playground sites may have severe implications in children's health. Therefore, further studies are required to characterize the size distribution, structure, shape and composition of such minerals which are essential factors related to the toxicology of inhaled dust particles.

GALECTIN-8 Is a Neuroprotective Factor in the Brain that Can Be Neutralized by Human Autoantibodies.

Galectin-8 (Gal-8) is a glycan-binding protein that modulates a variety of cellular processes interacting with cell surface glycoproteins. Neutralizing anti-Gal-8 antibodies that block Gal-8 functions have been described in autoimmune and inflammatory disorders, likely playing pathogenic roles. In the brain, Gal-8 is highly expressed in the choroid plexus and accordingly has been detected in human cerebrospinal fluid. It protects against central nervous system autoimmune damage through its immune-suppressive potential. Whether Gal-8 plays a direct role upon neurons remains unknown. Here, we show that Gal-8 protects hippocampal neurons in primary culture against damaging conditions such as nutrient deprivation, glutamate-induced excitotoxicity, hydrogen peroxide (H2O2)-induced oxidative stress, and ß-amyloid oligomers (Aßo). This protective action is manifested even after 2 h of exposure to the harmful condition. Pull-down assays demonstrate binding of Gal-8 to selected ß1-integrins, including α3 and α5ß1. Furthermore, Gal-8 activates ß1-integrins, ERK1/2, and PI3K/AKT signaling pathways that mediate neuroprotection. Hippocampal neurons in primary culture produce and secrete Gal-8, and their survival decreases upon incubation with human function-blocking Gal-8 autoantibodies obtained from lupus patients. Despite the low levels of Gal-8 expression detected by real-time PCR in hippocampus, compared with other brain regions, the complete lack of Gal-8 in Gal-8 KO mice determines higher levels of apoptosis upon H2O2 stereotaxic injection in this region. Therefore, endogenous Gal-8 likely contributes to generate a neuroprotective environment in the brain, which might be eventually counteracted by human function-blocking autoantibodies.

Implementing an Information System Strategy: A Cost, Benefit, and Risk Analysis Framework for Evaluating Viable IT Alternatives in the US Federal Government.

In the US Federal government, an analysis of alternatives (AoA) is required for a significant investment of resources. The AoA yields the recommended alternative from a set of viable alternatives for the investment decision. This paper presents an integrated AoA and project management framework for analyzing new or emerging alternatives (e.g., Cloud computing), as may be driven by an information system strategy that incorporates a methodology for analyzing the costs, benefits, and risks of each viable alternative. The case study in this paper, about a business improvement project to provide public health and safety services to citizens in a US Federal agency, is a practical application of this integrated framework and reveals the benefits of this integrated approach for an investment decision. The decision making process in the framework-as an integrated, organized, and adaptable set of management and control practices-offers a defensible recommendation and provides accountability to stakeholders.

Source apportionment and environmental fate of lead chromates in atmospheric dust in arid environments.

The environmental fate of lead derived from traffic paint has been poorly studied in developing countries, mainly in arid zones. For this purpose, a developing city located in the Sonoran desert (Hermosillo, Mexico), was chosen to conduct a study. In this paper the lead chromate (crocoite) sources in atmospheric dust were addressed using a combination of Raman microspectroscopy, X-ray diffraction, scanning electron microscopy (SEM), and Pb isotope measurements. A high concentration of Pb and Cr as micro- and nanostructured pigments of crocoite is reported in yellow traffic paint (n=80), road dust (n=146), settled dust in roofs (n=21), and atmospheric dust (n=20) from a developing city located in the Sonoran Desert. 10 samples of peri-urban soils were collected for local geochemical background. The paint photodegradation and erosion of the asphaltic cover are enhanced by the climate, and the presence of the mineral crocoite (PbCrO4) in road dust with an aerodynamic diameter ranging from 100nm to 2µm suggests its integration into the atmosphere by wind resuspension processes. A positive PbCr correlation (R2=0.977) was found for all studied samples, suggesting a common source. The Pb-isotope data show signatures in atmospheric dust as a product of the mixing of two end members: i) local soils and ii) crocoite crystals as pigments in paint. The presence of lead chromates in atmospheric dust has not been previously documented in Latin America, and it represents an unknown health risk to the exposed population because the identified size of crystals can reach the deepest part of lungs.

Biological variation of plasma osmolality obtained with capillary versus venous blood.

BACKGROUND: Plasma osmolality (POsm) is a gold standard to assess hydration status but requires venipuncture. POsm obtained by lancing a digit, a source of capillary puncture blood (CAP), has not been validated. This study compared POsm from CAP versus venous blood (VEN) and validated its sensitivity to detect dehydration. METHODS: Healthy young adults (Study A: n=20 men, 22 women; Study B: n=23 men, 23 women) participated. In Study A, CAP and VEN were compared under controlled euhydration meeting dietary reference intakes for water (3.7 L men, 2.7 L women). In Study B, CAP was assessed for sensitivity to detect dehydration with receiver operating characteristic analysis over two 24 h periods: euhydration for 24 h followed by water restriction over 24 h. POsm was measured using freezing point depression. RESULTS: For all subjects, CAP POsm (283.0±3.9 mOsm/kg) was not significantly different (p=0.07) from VEN (284.2±3.5) during euhydration and met analytical goals for individuality and heterogeneity. When outliers (n=3) were eliminated, mean difference was -1.6 (±3.2) lower (p<0.01) with CAP. Fluid restriction increased (p<0.001) CAP POsm (284.0±4.4 to 292.8±5.2 mOsm/kg), achieving excellent accuracy (0.92) and sensitivity (89.1%) to predict mild dehydration (2% body mass loss). CONCLUSIONS: POsm via CAP exhibited similar coefficients of variation and analytical goals compared to VEN combined with excellent accuracy and sensitivity to detect dehydration. Although CAP values were approximately 2 mOsm/kg lower than VEN, CAP appears an adequate substitute for tracking changes in non-clinical settings.

Predictors of successful use of a web-based healthcare document storage and sharing system for pediatric cancer survivors: Cancer SurvivorLink™.

PURPOSE: Cancer SurvivorLink™, www.cancersurvivorlink.org , is a patient-controlled communication tool where survivors can electronically store and share documents with healthcare providers. Functionally, SurvivorLink serves as an electronic personal health record-a record of health-related information managed and controlled by the survivor. Recruitment methods to increase registration and the characteristics of registrants who completed each step of using SurvivorLink are described. METHODS: Pediatric cancer survivors were recruited via mailings, survivor clinic, and community events. Recruitment method and Aflac Survivor Clinic attendance was determined for each registrant. Registration date, registrant type (parent vs. survivor), zip code, creation of a personal health record in SurvivorLink, storage of documents, and document sharing were measured. Logistic regression was used to determine the characteristics that predicted creation of a health record and storage of documents. RESULTS: To date, 275 survivors/parents have completed registration: 63 were recruited via mailing, 99 from clinic, 56 from community events, and 57 via other methods. Overall, 66.9 % registrants created a personal health record and 45.7 % of those stored a health document. There were no significant predictors for creating a personal health record. Attending a survivor clinic was the strongest predictor of document storage (p < 0.01). Of those with a document stored, 21.4 % shared with a provider. CONCLUSIONS: Having attended survivor clinic is the biggest predictor of registering and using SurvivorLink. IMPLICATIONS FOR CANCER SURVIVORS: Many survivors must advocate for their survivorship care. Survivor Link provides educational material and supports the dissemination of survivor-specific follow-up recommendations to facilitate shared clinical care decision making.

Primary care providers as partners in long-term follow-up of pediatric cancer survivors.

PURPOSE: To develop a model of shared healthcare delivery that includes primary care providers (PCP) and ensures best practice in follow-up of pediatric cancer survivors. METHOD: Structured interviews with healthcare professionals (HCPs) were used to ascertain familiarity and confidence in providing care to survivors. Partnerships were made with HCP societies, and survivor care lectures were given at HCP meetings. HCP's preferences for ongoing continuing education (CE) opportunities were ascertained. Cancer SurvivorLink(TM), a web-based tool, was developed to allow patients to securely store their healthcare documents and share them electronically with registered HCPs. Educational material developed for Cancer SurvivorLink(TM) includes CE modules and QuickFacts--concise summaries of late effects. Website utilization was monitored utilizing Google Analytics. RESULTS: HCPs described moderate to very low familiarity with survivor care, but high interest in online CE learning. Thirty-one lectures were given to HCP groups to increase awareness. Preferred types of ongoing CE were: lectures, online text, and video modules. CE material was developed based on feedback from HCPs and website utilizations and includes 19 QuickFacts and 5 CE modules. During the first year, the website had 471 unique visitors and 1,129 total visits. QuickFacts received 345 views with Neurocognitive, Survivor Care 101, and Endocrine being most visited, and 49 CME modules have been completed. CONCLUSIONS: PCPs are interested in partnering in models of shared care for pediatric cancer survivors. Effective educational initiatives include lectures within HCP's professional education constructs and web-based CE opportunities. PCP involvement in survivor care alleviates some barriers to care such as geographic distance to the the cancer center and ensures that more pediatric cancer survivors receive recommended coordinated surveillance for late effects of cancer therapy.

Comunicación preliminar sobre la presencia de Trypanosoma cruzi en departamentos del norte y nororiente del Perú / Preliminary report on Trypanosoma cruzi presence in Peruvian North and Northeast departments

Objetivo: Realizar un estudio epidemiológico de la zona norte y nororiental del Perú sobre la presencia de enfermedad de Chagas y sus vectores. Diseño: Estudio descriptivo, transversal. Institución: Instituto de Medicina Tropical Daniel A. Carrión, Facultad de Medicina, Universidad Nacional Mayor de San Marcos, Lima, Perú. Material biológico: Triatominos positivos a Trypanosoma cruzi Chagas 1909, ratones machos Swiss-Webster de un mes de edad. Intervenciones: En septiembre de 2008, se visitó las localidades de Chilete, Paredones, en la Provincia de Contumazá, Cajamarca, y las localidades de Pampa Larca, La Puerta, Guitarras y Suyo en la provincia de Ayabaca, Piura, colectándose 10 especímenes de Panstrongylus chinai (Del Ponte, 1929) en Piura y 12 especímenes de Panstrongylus herreri (Wygodzinsky, 1948), en Chilete, Cajamarca. Se aisló las cepas de Trypanosoma en ratones blancos, machos, de un mes de edad, cepa Swiss webster, siendo estos mantenidos en el laboratorio por traspasos sucesivos. Se hizo la curva de parasitemia y el estudio morfométrico de los tripomastigotes sanguíneos. Los ratones infectados fueron sacrificados a los 30 días de inoculados, se separó las vísceras y en estas se hizo el estudio anatomopatológico. Se tomó 59 muestras de sangre a los habitantes de las zonas en estudio, de pulpa digital, en papel filtro, para búsqueda de anticuerpos IgG anti-T. cruzi por ELISA y reacción de inmunofluorescencia indirecta (IFI). Principales medidas de resultados: Identificación de los triatominos y determinar su infección por Trypanosoma cruzi; presencia de anticuerpos IgG anti- T. cruzi en los pobladores. Resultados: De los especímenes de triatominos colectados, se encontró dos especímenes de P. chinai y uno de P. herreri positivos a Trypanosoma cruzi. El pico máximo de la curva de parasitemia, ocurrió a los 20 días y se halló nidos de amastigotes de T. cruzi en miocardio y músculo esquelético de los ratones. En los habitantes de las zonas, diez (16,9 por ciento) de las muestras de sangre fueron reactivas a anticuerpos IgG anti-T. cruzi, con resultados concordantes para ambas técnicas. Conclusiones: La presencia del parásito en los vectores y de sus anticuerpos en humanos confirma que en los lugares estudiados de la zona norte y nororiente del Perú existe la infección por T. cruzi en forma activa, con todos los eslabones de la cadena epidemiológica para contraer dicha infección.

Objectives: To perform an epidemiological study on presence of ChagaÆs disease and its vectors at northern and nor oriental Peru. Design: Descriptive, transversal study. Setting: Daniel A. Carrion Tropical Medicine Institute, Faculty of Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru. Biologic material: Triatomines positive to Trypanosoma cruzi Chagas 1909; one month-old Swiss-Webster male rats. Interventions: In September 2008 a visit was done to Chilete, Paredones, Contumaza province, Cajamarca, and to Pampa Larca, La Puerta, Guitarras and Suyo at Ayabaca province, Piura, collecting 10 Panstrongylus chinai (Del Ponte, 1929) specimens at Piura and 12 Panstrongylus herreri (Wygodzinsky, 1948) specimens at Chilete, Cajamarca. Trypanosoma strains were isolated in Swiss Webster white male one month-old rats, and maintained by successive transfers. Both parasitemia curve and morphometric study of blood tripomastigotes were done. Infected rats were sacrificed at 30 days from inoculation, viscera were separated and pathology study was performed. Fifty-nine blood samples were obtained from inhabitantsÆ finger pulp in paper filter to look for IgG anti-T. cruzi antibodies by ELISA and indirect immunofluorescence (IIF). Main outcome measures: Identification of triatomines and infection by Trypanosoma cruzi; presence of IgG anti- T. cruzi antibodies in inhabitants. Results: Two P. chinai and one P. herreri specimens were positive for Trypanosoma cruzi in the triatomines collected. Maximum peak of parasitemia curve occurred at 20 days. T. cruzi amastigotes nests were found in rat myocardium and skeletal muscle. Ten inhabitantÆs blood samples (16,9 per cent) were reactive to IgG anti-T. cruzi antibodies, with concordant results for both techniques. Conclusions: Presence of the parasite in vectors and of antibodies in humans confirmed that in Peruvian northern and nor oriental settings there exists active T. cruzi infection with all epidemiological chain links present to develop the disease.