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2.
Lancet Oncol ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38621404

RESUMO

BACKGROUND: Patients with cancer are at greater risk of dying from COVID-19 than many other patient groups. However, how this risk evolved during the pandemic remains unclear. We aimed to determine, on the basis of the UK national pandemic protocol, how factors influencing hospital mortality from COVID-19 could differentially affect patients undergoing cancer treatment. We also examined changes in hospital mortality and escalation of care in patients on cancer treatment during the first 2 years of the COVID-19 pandemic in the UK. METHODS: We conducted a prospective cohort study of patients aged older than 19 years and admitted to 306 health-care facilities in the UK with confirmed SARS-CoV-2 infection, who were enrolled in the International Severe Acute Respiratory and emerging Infections Consortium (ISARIC) WHO Clinical Characterisation Protocol (CCP) across the UK from April 23, 2020, to Feb 28, 2022; this analysis included all patients in the complete dataset when the study closed. The primary outcome was 30-day in-hospital mortality, comparing patients on cancer treatment and those without cancer. The study was approved by the South Central-Oxford C Research Ethics Committee in England (Ref: 13/SC/0149) and the Scotland A Research Ethics Committee (Ref 20/SS/0028), and is registered on the ISRCTN Registry (ISRCTN66726260). FINDINGS: 177 871 eligible adult patients either with no history of cancer (n=171 303) or on cancer treatment (n=6568) were enrolled; 93 205 (52·4%) were male, 84 418 (47·5%) were female, and in 248 (13·9%) sex or gender details were not specified or data were missing. Patients were followed up for a median of 13 (IQR 6-21) days. Of the 6568 patients receiving cancer treatment, 2080 (31·7%) died at 30 days, compared with 30 901 (18·0%) of 171 303 patients without cancer. Patients aged younger than 50 years on cancer treatment had the highest age-adjusted relative risk (hazard ratio [HR] 5·2 [95% CI 4·0-6·6], p<0·0001; vs 50-69 years 2·4 [2·2-2·6], p<0·0001; 70-79 years 1·8 [1·6-2·0], p<0·0001; and >80 years 1·5 [1·3-1·6], p<0·0001) but a lower absolute risk (51 [6·7%] of 763 patients <50 years died compared with 459 [30·2%] of 1522 patients aged >80 years). In-hospital mortality decreased for all patients during the pandemic but was higher for patients on cancer treatment than for those without cancer throughout the study period. INTERPRETATION: People with cancer have a higher risk of mortality from COVID-19 than those without cancer. Patients younger than 50 years with cancer treatment have the highest relative risk of death. Continued action is needed to mitigate the poor outcomes in patients with cancer, such as through optimising vaccination, long-acting passive immunisation, and early access to therapeutics. These findings underscore the importance of the ISARIC-WHO pandemic preparedness initiative. FUNDING: National Institute for Health Research and the Medical Research Council.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38609346

RESUMO

BACKGROUND: Thirty-day readmission rate after heart failure (HF) hospitalization is widely used to evaluate healthcare quality. Methodology may substantially influence estimated rates. We assessed the impact of different definitions on HF and all-cause readmission rates. METHODS: Readmission rates were examined in 1,835 patients discharged following HF hospitalization using 64 unique definitions derived from five methodological factors: (1) ICD-10 codes (broad vs narrow), (2) index admission selection (single admission only first-in-year vs. random sample; or multiple admissions in year with vs. without 30-day blanking period), (3) variable denominator (number alive at discharge vs. number alive at 30-days), (4) follow-up period start (discharge date vs day following discharge), and (5) annual reference-period (calendar vs fiscal). The impact of different factors was assessed using linear-regression. RESULTS: The calculated 30-day readmission rate for HF varied more than 2-fold depending solely on the methodological approach (6.5% to 15.0%). All-cause admission rates exhibited similar variation (18.8% to 29.9%). The highest rates included all consecutive index admissions (HF 11.1-15.0%, all-cause 24.0-29.9%), and lowest only one index admission per patient per year (HF 6.5-11.3%, all-cause 18.8-22.7%). When including multiple index admissions and compared to blanking the 30-days post-discharge, not blanking was associated with 2.3% higher readmission rates. Selecting a single admission per year with a first-in-year approach lowered readmission rates by 1.5%, while random-sampling admissions lowered estimates further by 5.2% (p<0.001). CONCLUSION: Calculated 30-day readmission rates varied more than 2-fold by altering methods. Transparent and consistent methods are needed to ensure reproducible and comparable reporting.

5.
Int J Audiol ; : 1-8, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38613519

RESUMO

OBJECTIVE: This study aimed to investigate the connection between psychological factors and postoperative tinnitus in vestibular schwannoma (VS) patients following retrosigmoid microsurgery. DESIGN: Cross-sectional study. STUDY SAMPLE: Ninety-three VS patients participated, completing questionnaires on demographics, tinnitus severity (THI-12), personality traits (TIPI-G), dizziness impact (DHI), perceived health benefits (GBI), somatisation tendencies (SOMS-2), and psychological distress (HADS-D). Our analysis involved Mann-Whitney U-tests, Spearman's rank-order correlations, and false discovery rate correction. RESULTS: Most participants reported postoperative tinnitus (77/93), with 41 experiencing it preoperatively. Emotional stability correlated negatively with tinnitus presence, while tinnitus severity was associated with emotional distress. Preoperative somatisation tendencies were also positively linked to tinnitus severity. Postoperative Tinnitus was further linked to reduced perceived health benefits and increased anxiety and depression levels. Notably, age and gender showed no significant associations. CONCLUSION: This study uncovers the interplay between postoperative tinnitus and psychological factors in VS patients, highlighting emotional and cognitive dimensions. Tailored psychological interventions addressing tinnitus's psychosomatic impact may enhance patients quality of life.

6.
Acad Pediatr ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38614214

RESUMO

OBJECTIVES: To measure the impact of the COVID-19 pandemic on racial and ethnic disparities in attendance to well-child visit recommendations. METHODS: We used the nationally representative Medical Expenditure Panel Survey (MEPS) to compare pre-pandemic (2018-2019) and pandemic (2020 and 2021) ratios of well-child visits to age-based recommendations, presenting both unadjusted and adjusted attendance disparities over time. We also used the 1996-2021 MEPS to place the pandemic changes in an historical context. RESULTS: Average attendance decreased from 66.6% in 2018-2019 (95% confidence interval [CI]: 64.1, 69.1) to 58.6% in 2020 (95% CI: 55.5, 61.6), rebounding to 65.1% in 2021 (95% CI: 61.5, 68.7). The unadjusted disparity in attendance between White non-Hispanic and Black non-Hispanic children widened from 9.6 percentage points in 2018-2019 (95% CI: 2.8, 16.4) to 24.8 percentage points in 2020 (95% CI: 17.5, 32.2) and 21.4 percentage points in 2021 (95% CI: 11.2, 31.5). The unadjusted disparity in attendance between White non-Hispanic and Hispanic children widened from 14.8 percentage points in 2018-2019 (95% CI: 9.7, 19.8) to 26.3 percentage points in 2020 (95% CI: 19.9, 32.7) and 24.9 percentage points in 2021 (95% CI: 17.5, 32.3). Changes in disparities were large even when we controlled for health status, demographic and socioeconomic characteristics, health insurance, and state of residence. Magnitudes of the racial and ethnic attendance disparities during the pandemic's first two years were unprecedented since before 1996. CONCLUSIONS: Widening attendance disparities during the pandemic highlight the need to build a more equitable healthcare system for all children. WHAT'S NEW: Using nationally representative household data we show that racial and ethnic disparities in attendance to well-child visit recommendations widened to unprecedented levels during the first two years of the COVID-19 pandemic.

7.
Mol Brain ; 17(1): 18, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605409

RESUMO

One of the main burdens in the treatment of diseases is imputable to the delay between the appearance of molecular dysfunctions in the first affected disease cells and their presence in sufficient number for detection in specific tissues or organs. This delay obviously plays in favor of disease progression to an extent that makes efficient treatments difficult, as they arrive too late. The development of a novel medical strategy, termed cell-based interception and precision medicine, seeks to identify dysfunctional cells early, when tissue damages are not apparent and symptoms not yet present, and develop therapies to treat diseases early. Central to this strategy is the use of single-cell technologies that allow detection of molecular changes in cells at the time of phenotypical bifurcation from health to disease. In this article we describe a general procedure to support such an approach applied to neurodegenerative disorders. This procedure combines four components directed towards highly complementary objectives: 1) a high-performance single-cell proteomics (SCP) method (Detect), 2) the development of disease experimental cell models and predictive computational models of cell trajectories (Understand), 3) the discovery of specific targets and personalized therapies (Cure), and 4) the creation of a community of collaborating laboratories to accelerate the development of this novel medical paradigm (Collaborate). A global initiative named 37TrillionCells (37TC) was launched to advance the development of cell-based interception and precision medicine.


Assuntos
Doenças Neurodegenerativas , Humanos , Doenças Neurodegenerativas/terapia , Medicina de Precisão/métodos , Atenção à Saúde , Proteômica/métodos
8.
Urol Clin North Am ; 51(2): 221-232, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38609194

RESUMO

Detrusor sphincter dyssynergia (DSD) is defined as a detrusor contraction concurrent with an involuntary contraction of the urethral and/or periurethral striated muscles typically occurring in a patient with a spinal cord lesion above the sacral cord. Consequently, high urethral closure pressures during the detrusor contraction leads to high intravesical voiding pressure and large postvoid residuals, which can lead to significant complications in up to 50% of patients if DSD is not treated and followed-up regularly. DSD treatment options are centered around symptomatic management rather that addressing the underlying causative mechanisms.


Assuntos
Ataxia , Uretra , Humanos
9.
Ann Card Anaesth ; 27(2): 111-120, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38607874

RESUMO

ABSTRACT: The potential benefits of epidural anesthesia on mortality, atrial fibrillation, and pulmonary complications must be weighed against the risk of epidural hematoma associated with intraoperative heparinization. This study aims to provide an updated assessment of the clinical risks of epidural anesthesia in cardiac surgery, focusing on the occurrence of epidural hematomas and subsequent paralysis. A systematic search of Embase, Medline, Ovid Central, Web of Science, and PubMed was conducted to identify relevant publications between 1966 and 2022. Two independent reviewers assessed the eligibility of the retrieved manuscripts. Studies reporting adult patients undergoing cardiac surgery with epidural catheterization were included. The incidence of hematomas was calculated by dividing the number of hematomas by the total number of patients in the included studies. Risk calculations utilized various denominators based on the rigor of trial designs, and the risks of hematoma and paralysis were compared to other commonly encountered risks. The analysis included a total of 33,089 patients who underwent cardiac surgery with epidural catheterization. No epidural hematomas were reported across all published RCTs, prospective, and retrospective trials. Four case reports associated epidural hematoma with epidural catheterization and perioperative heparinization. The risks of epidural hematoma and subsequent paralysis were estimated at 1:7643 (95% CI 1:3860 to 380,916) and 1:10,190 (95% CI 1:4781 to 0:1), respectively. The risk of hematoma is similar to the non-obstetric population (1:5405; 95% CI 1:4784 to 6134). The risk of hematoma in cardiac surgery patients receiving epidural anesthesia is therefore similar to that observed in some other surgical non-obstetric populations commonly exposed to epidural catheterization.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Adulto , Humanos , Estudos Prospectivos , Estudos Retrospectivos , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Hematoma , Medição de Risco , Paralisia
10.
JAMA Cardiol ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38581644

RESUMO

Importance: Aortic stenosis (AS) is a major public health challenge with a growing therapeutic landscape, but current biomarkers do not inform personalized screening and follow-up. A video-based artificial intelligence (AI) biomarker (Digital AS Severity index [DASSi]) can detect severe AS using single-view long-axis echocardiography without Doppler characterization. Objective: To deploy DASSi to patients with no AS or with mild or moderate AS at baseline to identify AS development and progression. Design, Setting, and Participants: This is a cohort study that examined 2 cohorts of patients without severe AS undergoing echocardiography in the Yale New Haven Health System (YNHHS; 2015-2021) and Cedars-Sinai Medical Center (CSMC; 2018-2019). A novel computational pipeline for the cross-modal translation of DASSi into cardiac magnetic resonance (CMR) imaging was further developed in the UK Biobank. Analyses were performed between August 2023 and February 2024. Exposure: DASSi (range, 0-1) derived from AI applied to echocardiography and CMR videos. Main Outcomes and Measures: Annualized change in peak aortic valve velocity (AV-Vmax) and late (>6 months) aortic valve replacement (AVR). Results: A total of 12 599 participants were included in the echocardiographic study (YNHHS: n = 8798; median [IQR] age, 71 [60-80] years; 4250 [48.3%] women; median [IQR] follow-up, 4.1 [2.4-5.4] years; and CSMC: n = 3801; median [IQR] age, 67 [54-78] years; 1685 [44.3%] women; median [IQR] follow-up, 3.4 [2.8-3.9] years). Higher baseline DASSi was associated with faster progression in AV-Vmax (per 0.1 DASSi increment: YNHHS, 0.033 m/s per year [95% CI, 0.028-0.038] among 5483 participants; CSMC, 0.082 m/s per year [95% CI, 0.053-0.111] among 1292 participants), with values of 0.2 or greater associated with a 4- to 5-fold higher AVR risk than values less than 0.2 (YNHHS: 715 events; adjusted hazard ratio [HR], 4.97 [95% CI, 2.71-5.82]; CSMC: 56 events; adjusted HR, 4.04 [95% CI, 0.92-17.70]), independent of age, sex, race, ethnicity, ejection fraction, and AV-Vmax. This was reproduced across 45 474 participants (median [IQR] age, 65 [59-71] years; 23 559 [51.8%] women; median [IQR] follow-up, 2.5 [1.6-3.9] years) undergoing CMR imaging in the UK Biobank (for participants with DASSi ≥0.2 vs those with DASSi <.02, adjusted HR, 11.38 [95% CI, 2.56-50.57]). Saliency maps and phenome-wide association studies supported associations with cardiac structure and function and traditional cardiovascular risk factors. Conclusions and Relevance: In this cohort study of patients without severe AS undergoing echocardiography or CMR imaging, a new AI-based video biomarker was independently associated with AS development and progression, enabling opportunistic risk stratification across cardiovascular imaging modalities as well as potential application on handheld devices.

11.
Br J Haematol ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38577716

RESUMO

Multiagent chemoimmunotherapy remains the standard of care treatment for Burkitt lymphoma leading to a cure in the majority of cases. However, frontline treatment regimens are associated with a significant risk of treatment related toxicity especially in elderly and immunocompromised patients. Additionally, prognosis remains dismal in refractory/relapsed Burkitt lymphoma. Thus, novel therapies are required to not only improve outcomes in relapsed/refractory Burkitt lymphoma but also minimize frontline treatment related toxicities. Recurrent genomic changes and signalling pathway alterations that have been implicated in the Burkitt lymphomagenesis include cell cycle dysregulation, cell proliferation, inhibition of apoptosis, epigenetic dysregulation and tonic B-cell receptor-phosphatidylinositol 3-kinase (BCR-PI3K) signalling. Here, we will discuss novel targeted therapy approaches using small molecule inhibitors that could pave the way to the future treatment landscape based on the understanding of recurrent genomic changes and signalling pathway alterations in the lymphomagenesis of adult Burkitt lymphoma.

12.
G3 (Bethesda) ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38577978

RESUMO

Genetic variability significantly contributes to individual differences in skeletal muscle mass; however, the specific genes involved in that process remain elusive. In this study, we examined the role of positional candidates, Rps6ka6 and Pou3f4, of a chromosome X locus, implicated in muscle mass variability in CFW laboratory mice. Histology of hindlimb muscles was studied in CFW male mice carrying the muscle "increasing" allele C (n = 15) or "decreasing" allele T (n = 15) at the peak marker of the locus, rs31308852, and in the Pou3f4y/- and their wild-type male littermates. To study the role of the Rps6ka6 gene, we deleted exon 7 (Rps6ka6-ΔE7) using clustered regularly interspaced palindromic repeats-Cas9 based method in H2Kb myogenic cells creating a severely truncated RSK4 protein. We then tested whether that mutation affected myoblast proliferation, migration, and/or differentiation. The extensor digitorum longus muscle was 7% larger (P < 0.0001) due to 10% more muscle fibers (P = 0.0176) in the carriers of the "increasing" compared with the "decreasing" CFW allele. The number of fibers was reduced by 15% (P = 0.0268) in the slow-twitch soleus but not in the fast-twitch extensor digitorum longus (P = 0.2947) of Pou3f4y/- mice. The proliferation and migration did not differ between the Rps6ka6-ΔE7 and wild-type H2Kb myoblasts. However, indices of differentiation (myosin expression, P < 0.0001; size of myosin-expressing cells, P < 0.0001; and fusion index, P = 0.0013) were significantly reduced in Rps6ka6-ΔE7 cells. This study suggests that the effect of the X chromosome locus on muscle fiber numbers in the fast-twitch extensor digitorum longus is mediated by the Rps6ka6 gene, whereas the Pou3f4 gene affects fiber number in slow-twitch soleus.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38578584

RESUMO

Anxiety and depressive difficulties can emerge during early childhood and cause impairment in functioning. Anxiety and depressive behaviors and impairment are typically assessed with global questionnaires that require recall of children's behavior over an extended period which could reduce the accuracy of parent report of children's behavior and functioning. The current study compared parents' report of children's anxiety and depressive behaviors and impairment when evaluated with global measures versus a daily diary measure. Participants (N = 901 parents of 3-5-year-old children) completed global and daily measures of children's behavior and impairment during enrollment to the study. Global measures were completed at baseline and the 14 daily diary measures were completed consecutively for two weeks. Across most measures, daily associations between parent-reported anxiety and depressive behaviors and impairment were stronger compared to associations with global measures. These results suggest that daily measures may better capture links between young children's typical behavior and functioning compared to global measures. In addition, daily assessment might be more effective for measuring mild to moderate yet still impairing behaviors that may be missed on global reports that require longer periods of recall.

14.
Artigo em Inglês | MEDLINE | ID: mdl-38558166

RESUMO

BACKGROUND: Despite significant support system disruptions during the COVID-19 pandemic, little is known about the relationship between social support and symptom burden among older adults following COVID-19 hospitalization. METHODS: From a prospective cohort of 341 community-living persons aged ≥60 years hospitalized with COVID-19 between June 2020-June 2021 who underwent follow-up at 1, 3, and 6 months after discharge, we identified 311 participants with ≥1 follow-up assessment. Social support pre-hospitalization was ascertained using a 5-item version of the Medical Outcomes Study Social Support Survey (range, 5-25), with low social support defined as a score ≤15. At hospitalization and each follow-up assessment, 14 physical symptoms were assessed using a modified Edmonton Symptom Assessment System inclusive of COVID-19-relevant symptoms. Mental health symptoms were assessed using Patient Health Questionnaire-4. Longitudinal associations between social support and physical and mental health symptoms, respectively, were evaluated through multivariable regression. RESULTS: Participants' mean age was 71.3 years (standard deviation, 8.5), 52.4% were female, and 34.2% were of Black race or Hispanic ethnicity. 11.8% reported low social support. Over the 6-month follow-up period, low social support was independently associated with higher burden of physical symptoms (adjusted rate ratio [aRR], 1.26; 95% confidence interval [CI], 1.05-1.52), but not mental health symptoms (aRR, 1.14; 95% CI, 0.85-1.53). CONCLUSIONS: Low social support is associated with greater physical, but not mental health, symptom burden among older survivors of COVID-19 hospitalization. Our findings suggest a potential need for social support screening and interventions to improve post-COVID-19 symptom management in this vulnerable group.

15.
J Pediatr ; : 114043, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38561049

RESUMO

OBJECTIVE: To predict extubation readiness in preterm infants using machine learning analysis of bedside pulse oximeter and ventilator data. STUDY DESIGN: This is an observational study with prospective recordings of oxygen saturation (SpO2) and ventilator data from infants < 30 weeks' gestation age (GA). Research pulse oximeters collected SpO2 (1 Hz sampling rate) to quantify intermittent hypoxemia (IH). Continuous ventilator metrics were collected (4-5 min sampling) from bedside ventilators. Data modeling was completed using unbiased machine learning algorithms. Three model sets were created using the following data source combinations: [1] IH and ventilator (IH + SIMV), [2] IH, and [3] ventilator (SIMV). Infants were also analyzed separated by postnatal age (infants < 2 or ≥ 2 weeks of age). Models were compared by area under the ROC curve (AUC). RESULTS: A total of 110 extubation events from 110 preterm infants were analyzed. Infants had a median GA and birth weight of 26 weeks and 825 grams, respectively. Of the three models presented, the IH + SIMV model achieved the highest AUC of 0.77 for all infants. Separating infants by postnatal age increased accuracy further achieving AUC of 0.94 for < 2 weeks of age group and AUC of 0.83 for ≥ 2 weeks group. CONCLUSIONS: Machine learning analysis has the potential to enhance prediction accuracy of extubation readiness in preterm infants while utilizing readily available data streams from bedside pulse oximeters and ventilators.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38566617

RESUMO

BACKGROUND: Diagnosis-code-based algorithms to identify fall injuries in Medicare data are useful for ascertaining outcomes in interventional and observational studies. However, these algorithms have not been validated against a fully external reference standard, in ICD-10-CM, or in Medicare Advantage (MA) data. METHODS: We linked self-reported fall injuries leading to medical attention (FIMA) from the Strategies to Reduce Injuries and Develop Confidence in Elders (STRIDE) trial (reference standard) to Medicare fee-for-service (FFS) and MA data from 2015-2019. We measured the area under the receiver operating characteristic curve (AUC) based on sensitivity and specificity of a diagnosis-code-based algorithm against the reference standard for presence or absence of ≥1 FIMA within a specified window of dates, varying the window size to obtain points on the curve. We stratified results by source (FFS versus MA), trial arm (intervention versus control), and STRIDE's ten participating healthcare systems. RESULTS: Both reference standard data and Medicare data were available for 4941 (of 5451) participants. The reference standard and algorithm identified 2054 and 2067 FIMA, respectively. The algorithm had 45% sensitivity (95% confidence interval [CI], 43%-47%) and 99% specificity (95% CI, 99%-99%) to identify reference standard FIMA within the same calendar month. The AUC was 0.79 (95% CI, 0.78-0.81) and was similar by FFS or MA data source or trial arm, but showed variation among STRIDE healthcare systems (AUC range by healthcare system, 0.71 to 0.84). CONCLUSIONS: An ICD-10-CM algorithm to identify fall injuries demonstrated acceptable performance against an external reference standard, in both MA and FFS data.

18.
Appl Opt ; 63(10): 2477-2486, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568526

RESUMO

The temperature dependence of optical window materials remains an important issue for a variety of applications from spacecraft, laser components, to high-speed aircraft. Concerning the refractive index in regions of transparency, current models are empirically based polynomial fits for the Sellmeier model strength and mode location parameters. These polynomial fit functions limit the ability to accurately extrapolate beyond the experimental range used to develop the fit functions. Thus, the development of a physics-based model as a function of temperature is an important goal for these critical materials. Such a model will allow extrapolation to higher and lower temperatures as long as the physical mechanisms do not change. For vibrational modes, a thermal average of the anharmonically shifted energy levels is investigated and compared to experimental data. The first anharmonic term can be estimated using the Morse potential based on a multiphonon absorption model. Experimentally, these modes redshift, and this is consistent with the developed temperature-dependent index of refraction Sellmeier model. This redshifting phenomena can also be applied to electronic transition shifts. In addition, the temperature-dependent oscillator number density can be obtained from known expansion coefficient models and experimental data. Other model parameters, in particular the electronic and vibrational mode polarizability, still need experimental grounding for a given material. The method is incorporated into a modified Sellmeier model format.

19.
Radiol Cardiothorac Imaging ; 6(2): e230182, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38602469

RESUMO

Fetal cardiac MRI using Doppler US gating is an emerging technique to support prenatal diagnosis of congenital heart disease and other cardiovascular abnormalities. Analogous to postnatal electrocardiographically gated cardiac MRI, this technique enables directly gated MRI of the fetal heart throughout the cardiac cycle, allowing for immediate data reconstruction and review of image quality. This review outlines the technical principles and challenges of cardiac MRI with Doppler US gating, such as loss of gating signal due to fetal movement. A practical workflow of patient preparation for the use of Doppler US-gated fetal cardiac MRI in clinical routine is provided. Currently applied MRI sequences (ie, cine or four-dimensional flow imaging), with special consideration of technical adaptations to the fetal heart, are summarized. The authors provide a literature review on the clinical benefits of Doppler US-gated fetal cardiac MRI for gaining additional diagnostic information on cardiovascular malformations and fetal hemodynamics. Finally, future perspectives of Doppler US-gated fetal cardiac MRI and further technical developments to reduce acquisition times and eliminate sources of artifacts are discussed. Keywords: MR Fetal, Ultrasound Doppler, Cardiac, Heart, Congenital, Obstetrics, Fetus Supplemental material is available for this article. © RSNA, 2024.


Assuntos
Imageamento por Ressonância Magnética , Cuidado Pré-Natal , Feminino , Gravidez , Humanos , Radiografia , Coração Fetal/diagnóstico por imagem , Tecnologia
20.
Can J Exp Psychol ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602813

RESUMO

Studies examining behavioural responses to emotional stimuli usually report one of two patterns of responses to negative stimuli. Some studies find faster responses to negative material. Other studies find slower responses to negative stimuli. While the attentional mechanisms proposed to explain these findings (attentional capture in the former case, delayed disengagement in the latter) are not at odds with one another, the behavioural findings do need to be reconciled. We posit that arousal, being the primary differentiator of threatening and nonthreatening stimuli, needs to be more carefully considered. To this end, two experiments were conducted evaluating the role of stimulus arousal and valence in the processing of schematic emotional faces. In Experiment 1, stimulus arousal was manipulated via the presence or absence of eyebrows in the schematic faces in a faces flanker task. Results showed faster responses to faces with eyebrows but no differences in the faces flanker asymmetry between faces with and without eyebrows. In Experiment 2, participants rated the faces on an evaluative space grid. Results showed the presence of the eyebrows had a greater impact on negative ratings for negative faces than for the other expressions. This suggests that stimulus valence and arousal were manipulated by the eyebrows and the reaction time differences could not be attributed purely to perceptual differences. Together these results suggests that both valence and arousal impact the processing of emotional schematic faces, and that these effects are dissociable. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

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