142 research outputs found

    Advancing Critical Care in the ICU: A Human-Centered Biomedical Data Visualization Systems

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    The purpose of this research is to provide medical clinicians with a new technology for interpreting large and diverse datasets to expedite critical care decision-making in the ICU. We refer to this technology as the medical information visualization assistant (MIVA). MIVA delivers multivariate biometric (bedside) data via a visualization display by transforming and organizing it into temporal resolutions that can provide contextual knowledge to clinicians. The result is a spatial organization of multiple datasets that allows rapid analysis and interpretation of trends. Findings from the usability study of the MIVA static prototype and heuristic inspection of the dynamic prototype suggest that using MIVA can yield faster and more accurate results. Furthermore, comments from the majority of the experimental group and the heuristic inspectors indicate that MIVA can facilitate clinical task flow in context-dependent health care settings

    Calcifilassi peniena: una rara complicanza in corso di emodialisi

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    La calcifilassi rappresenta una condizione clinica severa ed assai grave che si manifesta prevalentemente - ma non esclusivamente - in pazienti affetti da malattia renale cronica (CKD) sottoposti a terapia sostitutiva. Colpisce circa 1′1– 4% della popolazione dialitica (1, 2) e presenta una mortalità assai elevata (60–80%) (3). È caratterizzata clinicamente dalla presenza di ulcerazioni ischemiche a carico della cute e da necrosi conseguente allo sviluppo di calcificazioni distrofiche delle arteriole sottocutanee. L'interessamento penieno è assai raro ed in letteratura ne sono riportate - fino ad oggi - circa 40 segnalazioni. A tale proposito viene descritto il caso di un paziente di 50 anni, seguito presso la nostra UOC che sviluppò tale grave e, purtroppo fatale, complicanza clinica

    Terpene Composition Complexity Controls Secondary Organic Aerosol Yields from Scots Pine Volatile Emissions

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    Secondary organic aerosol (SOA) impact climate by scattering and absorbing radiation and contributing to cloud formation. SOA models are based on studies of simplified chemical systems that do not account for the chemical complexity in the atmosphere. This study investigated SOA formation from a mixture of real Scots pine (Pinus sylvestris) emissions including a variety of monoterpenes and sesquiterpenes. SOA generation was characterized from different combinations of volatile compounds as the plant emissions were altered with an herbivore stress treatment. During active herbivore feeding, monoterpene and sesquiterpene emissions increased, but SOA mass yields decreased after accounting for absorption effects. SOA mass yields were controlled by sesquiterpene emissions in healthy plants. In contrast, SOA mass yields from stressed plant emissions were controlled by the specific blend of monoterpene emissions. Conservative estimates using a box model approach showed a 1.5- to 2.3-fold aerosol enhancement when the terpene complexity was taken into account. This enhancement was relative to the commonly used model monoterpene, "alpha-pinene". These results suggest that simplifying terpene complexity in SOA models could lead to underpredictions in aerosol mass loading.Peer reviewe

    Quantification of biogenic volatile organic compounds with a flame ionization detector using the effective carbon number concept

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    Biogenic volatile organic compounds (BVOCs) are emitted into the atmosphere by plants and include isoprene, monoterpenes, sesquiterpenes, and their oxygenated derivatives. These BVOCs are among the principal factors influencing the oxidative capacity of the atmosphere in forested regions. BVOC emission rates are often measured by collecting samples onto adsorptive cartridges in the field and then transporting these samples to the laboratory for chromatographic analysis. One of the most commonly used detectors in chromatographic analysis is the flame ionization detector (FID). For quantitative analysis with an FID, relative response factors may be estimated using the effective carbon number (ECN) concept. The purpose of this study was to determine the ECN for a variety of terpenoid compounds to enable improved quantification of BVOC measurements. A dynamic dilution system was developed to make quantitative gas standards of VOCs with mixing ratios from 20–55 ppb. For each experiment using this system, one terpene standard was co-injected with an internal reference, n-octane, and analyzed via an automated cryofocusing system interfaced to a gas chromatograph flame ionization detector and mass spectrometer (GC/MS/FID). The ECNs of 16 compounds (14 BVOCs) were evaluated with this approach, with each test compound analyzed at least three times. The difference between the actual carbon number and measured ECN ranged from −24% to −2%. The difference between theoretical ECN and measured ECN ranged from −22% to 9%. Measured ECN values were within 10% of theoretical ECN values for most terpenoid compounds

    Insights into the O : C-dependent mechanisms controlling the evaporation of α-pinene secondary organic aerosol particles

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    The volatility of oxidation products of volatile organic compounds (VOCs) in the atmosphere is a key factor to determine if they partition into the particle phase contributing to secondary organic aerosol (SOA) mass. Thus, linking volatility and measured particle composition will provide insights into SOA formation and its fate in the atmosphere. We produced α-pinene SOA with three different oxidation levels (characterized by average oxygen-to-carbon ratio; O:C‾=0.53, 0.69, and 0.96) in an oxidation flow reactor. We investigated the particle volatility by isothermal evaporation in clean air as a function of relative humidity (RH &lt;2&thinsp;%, 40&thinsp;%, and 80&thinsp;%) and used a filter-based thermal desorption method to gain volatility and chemical composition information. We observed reduced particle evaporation for particles with increasing O:C‾ ratio, indicating that particles become more resilient to evaporation with oxidative aging. Particle evaporation was increased in the presence of water vapour and presumably particulate water; at the same time the resistance of the residual particles to thermal desorption was increased as well. For SOA with O:C‾=0.96, the unexpectedly large increase in mean thermal desorption temperature and changes in the thermogram shapes under wet conditions (80&thinsp;% RH) were an indication of aqueous phase chemistry. For the lower O:C‾ cases, some water-induced composition changes were observed. However, the enhanced evaporation under wet conditions could be explained by the reduction in particle viscosity from the semi-solid to liquid-like range, and the observed higher desorption temperature of the residual particles is a direct consequence of the increased removal of high-volatility and the continued presence of low-volatility compounds.</p

    Insolita causa di addome acuto in paziente adulto: l’ileo biliare

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    L’ileo biliare è una condizione morbosa rara descritta tra le complicanze della litiasi della colecisti. È causa dell’1-3% delle ostruzioni meccaniche del piccolo intestino. Interessa più frequentemente pazienti di età compresa tra 63 e 85 anni. La diagnosi pre-operatoria è generalmente posta con ritardo variabile da 1 a 10 giorni per l’assenza di una sintomatologia specifica. Caso clinico. Gli Autori riportano il caso di un uomo di 50 anni in cui è stata posta diagnosi di occlusione meccanica del piccolo intestino da voluminosa concrezione litiasica. L’occlusione ileale è stata dimostrata con la TC. Il paziente è stato sottoposto in urgenza ad intervento chirurgico, in un unico tempo, di enterolitotomia, colecistectomia e riparazione della fistola duodenale. Il decorso clinico è stato regolare e il paziente è stato dimesso in XIV giornata. Discussione. Nel nostro caso la diagnosi di ileo biliare è stata posta con un ritardo di 5 giorni. L’ecotomografia del fegato e delle vie biliari non è stata in grado di visualizzare la colecisti. La diagnosi è stata posta con la TC che si conferma gold standard diagnostico. Conclusioni. Lo stato clinico del paziente influenza la strategia chirurgica. Nel nostro paziente, considerato a basso rischio, è stato possibile l’intervento chirurgico in un unico tempo. La procedura in due tempi, enterolitotomia e successiva colecistectomia con riparazione della fistola, va riservata ai pazienti ad alto rischio

    Selective intrauterine growth restriction in monochorionic twins : changing patterns in umbilical artery Doppler flow and outcomes

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    Objectives: To describe changes in umbilical artery (UA) Doppler flow in monochorionic diamniotic (MCDA) twins affected by selective intrauterine growth restriction (sIUGR), to correlate Doppler findings with pregnancy course and perinatal outcome, and to report postnatal follow-up. Methods: This was a retrospective study of 140 MCDA twins with sIUGR. UA end-diastolic flow, defined as Doppler waveform pattern Type I (persistently positive), Type II (persistently absent or persistently reversed) or Type III (intermittently absent or intermittently reversed), was recorded at first examination and monitored weekly until double or single intrauterine fetal death (IUFD), bipolar cord coagulation or delivery. All neonates had an early neonatal brain scan, magnetic resonance imaging, when indicated, and neurological assessment during infancy. Rates (per 100 person-weeks) and hazard ratios (HR) of IUFD in the IUGR twin in each pregnancy were calculated considering UA Doppler pattern as a time-dependent variable. Results: At first examination, there were 65 cases with UA Doppler waveform pattern Type I, 62 with Type II and 13 with Type III. Of the 65 Type-I cases, 48 (74%) remained stable, while 17 (26%) changed to either Type II absent (14%), Type II reversed (9%) or Type III (3%). Of 62 Type-II cases (47 with absent and 15 with reversed flow), 33 (53%) remained stable (18 with absent and all 15 with reversed flow). The 29 Type-II absent cases which changed became Type II reversed (24/47, 51%) or Type III (5/47, 11%). All 13 Type-III cases remained stable. Compared with Type I, the risk of IUFD (adjusted for estimated fetal weight discordance and amniotic fluid deepest vertical pocket) was highest when the pregnancy was or became Type II reversed (HR, 9.5; 95% CI, 2.7\u201332.7) or Type II absent (HR, 4.3; 95% CI, 1.3\u201314.3). Mild neurological impairment was more prevalent in the IUGR twin than in the large cotwin (7% vs 1%, P = 0.02). Conclusions: Risk stratification based on UA Doppler is useful for planning ultrasound surveillance. However, patterns can change over time, with important consequences for management and outcome

    Treatment and outcome of 370 cases with spontaneous or post-laser twin anemia-polycythemia sequence managed in 17 fetal therapy centers.

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    OBJECTIVE: To investigate the antenatal management and outcome in a large international cohort of monochorionic twin pregnancies with spontaneous or post-laser twin anemia-polycythemia sequence (TAPS). METHODS: This study analyzed data of monochorionic twin pregnancies diagnosed antenatally with spontaneous or post-laser TAPS in 17 fetal therapy centers, recorded in the TAPS Registry between 2014 and 2019. Antenatal diagnosis of TAPS was based on fetal middle cerebral artery peak systolic velocity > 1.5 multiples of the median (MoM) in the TAPS donor and < 1.0 MoM in the TAPS recipient. The following antenatal management groups were defined: expectant management, delivery within 7 days after diagnosis, intrauterine transfusion (IUT) (with or without partial exchange transfusion (PET)), laser surgery and selective feticide. Cases were assigned to the management groups based on the first treatment that was received after diagnosis of TAPS. The primary outcomes were perinatal mortality and severe neonatal morbidity. The secondary outcome was diagnosis-to-birth interval. RESULTS: In total, 370 monochorionic twin pregnancies were diagnosed antenatally with TAPS during the study period and included in the study. Of these, 31% (n = 113) were managed expectantly, 30% (n = 110) with laser surgery, 19% (n = 70) with IUT (± PET), 12% (n = 43) with delivery, 8% (n = 30) with selective feticide and 1% (n = 4) underwent termination of pregnancy. Perinatal mortality occurred in 17% (39/225) of pregnancies in the expectant-management group, 18% (38/215) in the laser group, 18% (25/140) in the IUT (± PET) group, 10% (9/86) in the delivery group and in 7% (2/30) of the cotwins in the selective-feticide group. The incidence of severe neonatal morbidity was 49% (41/84) in the delivery group, 46% (56/122) in the IUT (± PET) group, 31% (60/193) in the expectant-management group, 31% (57/182) in the laser-surgery group and 25% (7/28) in the selective-feticide group. Median diagnosis-to-birth interval was longest after selective feticide (10.5 (interquartile range (IQR), 4.2-14.9) weeks), followed by laser surgery (9.7 (IQR, 6.6-12.7) weeks), expectant management (7.8 (IQR, 3.8-14.4) weeks), IUT (± PET) (4.0 (IQR, 2.0-6.9) weeks) and delivery (0.3 (IQR, 0.0-0.5) weeks). Treatment choice for TAPS varied greatly within and between the 17 fetal therapy centers. CONCLUSIONS: Antenatal treatment for TAPS differs considerably amongst fetal therapy centers. Perinatal mortality and morbidity were high in all management groups. Prolongation of pregnancy was best achieved by expectant management, treatment by laser surgery or selective feticide. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology
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