Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 147
Filtrar
1.
Early Hum Dev ; 192: 106012, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38648678

RESUMO

BACKGROUND: As a rule, newborns do not require special medical care. If unexpected complications occur peripartum or postpartum, support from and transport to specialised neonatal hospitals might be needed. METHODS: In a retrospective study, all transport protocols of a supraregional paediatric­neonatological maximum care hospital in northwestern Germany from 01.10.2018 through 30.09.2021 were analysed. The particular focus was on transports of newborns (<7 days) and the leading symptoms that led to contact. RESULTS: A total of 299 patients were included (average age of 15.4 h, 61.6 % males). The average complete transport time was approximately 2 h. Five leading neonatal diseases (respiratory, infectious, asphyxia, cardiac, haematological) were found to represent the causes of >80 % of transfers. Respiratory adaptation disorders are the main reason for transferring a newborn to a centre, whereas asphyxia is the most severe condition. The various symptoms differ in their time of onset, a factor which must be taken into account in practice. Differences were also found between different types of hospitals: while a large proportion of transports were carried out from maternity hospitals (80.6 %), children transported from children's hospitals were generally more severely ill. DISCUSSION: Transfers of neonates, especially from maternity hospitals to neonatal intensive care units due to special neonatal diseases, are not rare. In times of increasingly scarce resources, the effective care of sick or at-risk neonates is essential. For low-population regions, this means professional cooperation between maximum care providers and smaller children's hospitals and maternity-only hospitals.


Assuntos
Transporte de Pacientes , Humanos , Recém-Nascido , Feminino , Transporte de Pacientes/métodos , Transporte de Pacientes/estatística & dados numéricos , Masculino , Doenças do Recém-Nascido/terapia , Doenças do Recém-Nascido/epidemiologia , Alemanha , Estudos Retrospectivos , Transferência de Pacientes/estatística & dados numéricos
3.
BMC Infect Dis ; 24(1): 107, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38243223

RESUMO

BACKGROUND: In 2020, the WHO-approved Molbio Truenat platform and MTB assays to detect Mycobacterium tuberculosis complex (MTB) and resistance to rifampicin directly on sputum specimens. This primary health care center-based trial in Mozambique and Tanzania investigates the effect of Truenat platform/MTB assays (intervention arm) combined with rapid communication of results compared to standard of care on TB diagnosis and treatment initiation for microbiologically confirmed TB at 7 days from enrolment. METHODS: The Tuberculosis Close the Gap, Increase Access, and Provide Adequate Therapy (TB-CAPT) CORE trial employs a pragmatic cluster randomized controlled design to evaluate the impact of a streamlined strategy for delivery of Truenat platform/MTB assays testing at primary health centers. Twenty-nine centers equipped with TB microscopy units were selected to participate in the trial. Among them, fifteen health centers were randomized to the intervention arm (which involves onsite molecular testing using Truenat platform/MTB assays, process process optimization to enable same-day TB diagnosis and treatment initiation, and feedback on Molbio platform performance) or the control arm (which follows routine care, including on-site sputum smear microscopy and the referral of sputum samples to off-site Xpert testing sites). The primary outcome of the study is the absolute number and proportion of participants with TB microbiological confirmation starting TB treatment within 7 days of their first visit. Secondary outcomes include time to bacteriological confirmation, health outcomes up to 60 days from first visit, as well as user preferences, direct cost, and productivity analyses. ETHICS AND DISSEMINATION: TB-CAPT CORE trial has been approved by regulatory and ethical committees in Mozambique and Tanzania, as well as by each partner organization. Consent is informed and voluntary, and confidentiality of participants is maintained throughout. Study findings will be presented at scientific conferences and published in peer-reviewed international journals. TRIAL REGISTRATION: US National Institutes of Health's ClinicalTrials.gov, NCT04568954. Registered 23 September 2020.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Moçambique , Tanzânia , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico , Tuberculose/complicações , Rifampina/farmacologia , Atenção Primária à Saúde , Escarro/microbiologia , Sensibilidade e Especificidade , Ensaios Clínicos Controlados Aleatórios como Assunto
4.
Ann Cardiol Angeiol (Paris) ; 72(5): 101662, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37742408

RESUMO

Premature ventricular contractions (PVCs) are common. Although often benign, they can also be associated with increased morbidity and mortality. The aim of this review was to assess the risk evaluation of PVCs in patients with or without structural heart disease and discuss the management of this arrhythmia. Reports published in English were searched in PubMed with the following search terms: premature ventricular contraction, ectopic ventricular beat, ventricular extrasystole, antiarrhythmic drugs, ablation, ventricular arrhythmia, ventricular tachycardia, ventricular fibrillation and torsade de pointe. This analysis suggests that all patients with frequent PVCs should be assessed for PVC burden, symptom status and the presence of structural heart disease. PVCs in patients with structurally normal hearts was once considered a benign phenomenon. Uncommonly, PVCs may provoke life-threatening arrhythmias. Ventricular fibrillation is the initial mode of malignant rapid ventricular arrhythmias (MRVAs). Patients with malignant PVC and PVC burden >10% are at increased risk of MRVA in case of myocardial infarction and heart failure. MRVA is the primary cause of sudden cardiac death in patients with and without structural heart disease. Therapeutic options include medical therapy and catheter ablation, the latter more effective and potentially curable, particularly in patients with left ventricular dysfunction. The timely recognition and effective treatment of malignant PVCs in symptomatic patients with underling cardiomyopathy are mandatory to initiate early therapies before the occurrence of adverse clinical outcomes and to improve the long-term prognosis.

6.
Psychoneuroendocrinology ; 148: 105973, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36481577

RESUMO

BACKGROUND: Childbirth-related posttraumatic stress disorder (CB-PTSD) is gaining attention as a mental disorder with negative sequela for mothers and their offspring. Maternal trauma history is a well-known vulnerability factor for CB-PTSD symptoms (CB-PTSS). Furthermore, alterations of the hypothalamus-pituitary-adrenal axis have been linked to both trauma exposure and PTSD development. Hence, we investigated whether trauma history was associated with long-term glucocorticoid (GC) levels during pregnancy and their predictive role for CB-PTSS. Further, we examined whether GCs act as a mediator in the relationship between trauma history and CB-PTSS and whether this was moderated by the subjective birth experience. METHODS: 212 women participating in the prospective cohort study DREAMHAIR provided hair samples for quantification of long-term integrated cortisol and cortisone levels prior to their anticipated birth date accompanied by measures of trauma history. CB-PTSS and subjective birth experience were assessed two months postpartum. FINDINGS: Trauma history predicted elevated hair cortisol and hair cortisone during the third trimester of pregnancy, however associations did not remain significant when Bonferroni correction due to multiple testing was applied. Trauma history also predicted higher CB-PTSS. Hair GC levels during pregnancy neither predicted CB-PTSS two months after birth nor mediated the relationship between trauma history and CB-PTSS. The subjective birth experience moderated the relationship of hair cortisol and cortisone with CB-PTSS. CONCLUSION: Our data suggest that a history of trauma contributes to a higher risk to develop CB-PTSS and elevated long-term GC levels during the third pregnancy trimester. Further, the predictive role of hair cortisol and cortisone levels for CB-PTSS may depend on subjective birth experience. This highlights the need to consider the latter in future investigations when examining the role of stress-related biomarkers in more severely affected samples.


Assuntos
Cortisona , Transtornos de Estresse Pós-Traumáticos , Feminino , Humanos , Gravidez , Glucocorticoides , Hidrocortisona , Estudos Prospectivos , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Estresse Psicológico/complicações
7.
Public Health Action ; 12(1): 10-17, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35317535

RESUMO

BACKGROUND: The identification of patients with symptoms is the foundation of facility-based TB screening and diagnosis, but underdiagnosis is common. We conducted this systematic review with the hypothesis that underdiagnosis is largely secondary to patient drop out along the diagnostic and care pathway. METHODS: We searched (up to 22 January 2019) MEDLINE, Embase, and Cinahl for studies investigating patient pathway to TB diagnosis and care at health facilities. We used Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) to assess risk of bias. We reported proportions of patients with symptoms at each stage of the pathway from symptom screening to treatment initiation. RESULTS: After screening 3,558 abstracts, we identified 16 eligible studies. None provided data addressing the full cascade of care from clinical presentation to treatment initiation in the same patient population. Symptom screening, the critical entry point for diagnosis of TB, was not done for 33-96% of participants with symptoms in the three studies that reported this outcome. The proportion of attendees with symptoms offered a diagnostic investigation (data available for 15 studies) was very low with a study level median of 38% (IQR 14-44, range 4-84). CONCLUSIONS: Inefficiencies of the TB symptom screen-based patient pathway are a major contributor to underdiagnosis of TB, reflecting inconsistent implementation of guidelines to ask all patients attending health facilities about respiratory symptoms and to offer diagnostic tests to all patients promptly once TB symptoms are identified. Better screening tools and interventions to improve the efficiency of TB screening and diagnosis pathways in health facilities are urgently needed.


CONTEXTE: L'identification des patients symptomatiques est à la base du dépistage et du diagnostic de la TB en centres de soins, mais les sous-diagnostics sont fréquents. Nous avons réalisé cette revue systématique en émettant l'hypothèse que le sous-diagnostic était bien moins important que la perte de vue des patients tout au long du parcours diagnostique et thérapeutique. MÉTHODES: Nous avons interrogé les bases de données MEDLINE, Embase et Cinahl (jusqu'au 22 janvier 2019) pour identifier les études ayant évalué le parcours diagnostique et thérapeutique des patients atteints de TB en centres de soins. Nous avons utilisé le QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies 2) afin d'évaluer le risque de biais. Nous avons rapporté les proportions de patients présentant des symptômes à chaque stade du parcours, du dépistage symptomatique à l'instauration du traitement. RÉSULTATS: Après avoir passé en revue 3 558 résumés, nous avons identifié 16 études éligibles. Aucune ne fournissait, dans une même population de patients, de données sur l'ensemble de la cascade de soins, de la présentation clinique à l'instauration du traitement. Le dépistage symptomatique (point de départ essentiel du diagnostic de la TB) n'avait pas été réalisé pour 33­96% des participants symptomatiques dans les trois études ayant rapporté ce résultat. La proportion de personnes symptomatiques consultant à qui un examen diagnostique a été proposé (données disponibles pour 15 études) était très faible, avec une médiane de 38% (IQR 14­44 ; écart 4­84). CONCLUSIONS: Le manque d'efficacité du parcours patient fondé sur le dépistage symptomatique de la TB est un facteur contributif majeur du sous-diagnostic de la maladie. Cette inefficacité reflète une mise en œuvre incohérente des recommandations qui stipulent de demander à tous les patients consultant en centres de soins s'ils présentent des symptômes respiratoires et de proposer rapidement des tests diagnostiques à tous les patients une fois les symptômes de TB identifiés. De meilleurs outils et interventions de dépistage permettant d'améliorer l'efficacité du parcours de dépistage et de diagnostic de la TB en centres de soins sont urgemment nécessaires.

8.
Nat Commun ; 13(1): 1387, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35297401

RESUMO

Tailored nanoscale quantum light sources, matching the specific needs of use cases, are crucial building blocks for photonic quantum technologies. Several different approaches to realize solid-state quantum emitters with high performance have been pursued and different concepts for energy tuning have been established. However, the properties of the emitted photons are always defined by the individual quantum emitter and can therefore not be controlled with full flexibility. Here we introduce an all-optical nonlinear method to tailor and control the single photon emission. We demonstrate a laser-controlled down-conversion process from an excited state of a semiconductor quantum three-level system. Based on this concept, we realize energy tuning and polarization control of the single photon emission with a control-laser field. Our results mark an important step towards tailored single photon emission from a photonic quantum system based on quantum optical principles.

9.
Atherosclerosis ; 318: 22-31, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33450475

RESUMO

BACKGROUND AND AIMS: The value of serial coronary artery calcium (CAC) scores to predict changes in absolute myocardial perfusion and epicardial vasomotor function is poorly documented. This study explored the association between progression of CAC score and changes in absolute myocardial perfusion. METHODS: Fifty-three patients (26% female) with de novo single-vessel coronary artery disease underwent [15O]H2O positron emission tomography/computed tomography at 1 month (baseline), 1 year, and 3 years after complete revascularization with percutaneous coronary intervention (PCI) to assess CAC scores, hyperemic myocardial blood flow (hMBF), coronary flow reserve (CFR) and cold pressor test MBF (CPT-MBF), within the context of the VANISH trial. RESULTS: Baseline CAC score was 0 in 9%, 0.1-99.9 in 40%, 100-399.9 in 36% and ≥400 in 15% of patients, respectively. Mixed model-analysis allowed for averaging perfusion indices over all time points: hMBF (3.74 ± 0.83; 3.33 ± 0.79; 3.08 ± 0.78 and 2.44 ± 0.74 mL min-1·g-1) and CFR (3.82 ± 1.12; 3.17 ± 0.80; 3.19 ± 0.81; 2.63 ± 0.92) were lower among higher baseline CAC groups (p < 0.01; p = 0.03). However, no significant interaction was found between baseline CAC groups and time after PCI for all perfusion indices, denoting that evolution of perfusion indices over time was not significantly different between CAC groups. Furthermore, CAC progression was not correlated with evolution of hMBF (r = 0.08, p = 0.57), CFR (r = 0.09, p = 0.53) or CPT-MBF (r = 0.03, p = 0.82) during 3 years of follow-up. CONCLUSIONS: Higher baseline CAC was associated with lower hMBF and CFR. However, both baseline CAC and its progression were not associated with evolution of absolute hMBF, CFR and CPT-MBF over time, suggesting that CAC score and progression of CAC are poor indicators of change in absolute myocardial perfusion.


Assuntos
Doença da Artéria Coronariana , Imagem de Perfusão do Miocárdio , Intervenção Coronária Percutânea , Cálcio , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Circulação Coronária , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/cirurgia , Feminino , Humanos , Masculino , Intervenção Coronária Percutânea/efeitos adversos , Perfusão , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons
10.
Neth Heart J ; 28(Suppl 1): 57-65, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32780333

RESUMO

Determining the anatomic severity and extent of coronary artery disease (CAD) by means of coronary computed tomography angiography (CCTA) and its effect on perfusion using myocardial perfusion imaging (MPI) form the pillars of the non-invasive imaging assessment of CAD. This review will 1) focus on CCTA and [15O]H2O positron emission tomography MPI as stand-alone imaging modalities and their combined use for detecting CAD, 2) highlight some of the lessons learned from the PACIFIC trial (Comparison of Coronary CT Angiography, SPECT, PET, and Hybrid Imaging for Diagnosis of Ischemic Heart Disease Determined by Fractional Flow Reserve (FFR) (NCT01521468)), and 3) discuss the use of [15O]H2O PET MPI in the clinical work-up of patients with a chronic coronary total occlusion (CTO).

11.
Appl Opt ; 59(22): G112-G119, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32749323

RESUMO

Semiconductor microcavities are frequently studied in the context of semiconductor lasers and in application-oriented fundamental research on topics such as linear and nonlinear polariton systems, polariton lasers, polariton pattern formation, and polaritonic Bose-Einstein condensates. A commonly used approach to describe theoretical properties includes a phenomenological single-mode equation that complements the equation for the nonlinear optical response (interband polarization) of the semiconductor. Here, we show how to replace the single-mode equation by a fully predictive transfer function method that, in contrast to the single-mode equation, accounts for propagation, retardation, and pulse-filtering effects of the incident light field traversing the distributed Bragg reflector (DBR) mirrors, without substantially increasing the numerical complexity of the solution. As examples, we use cavities containing GaAs quantum wells and transition-metal dichalcogenides (TMDs).

12.
J Cardiovasc Comput Tomogr ; 14(1): 60-67, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31302028

RESUMO

BACKGROUND: Scan quality can have a significant effect on the diagnostic performance of non-invasive imaging techniques. However, the extent of its influence has scarcely been investigated in a head-to-head manner. METHODS: Two-hundred and eight patients underwent CCTA, SPECT, and PET prior to invasive fractional flow reserve measurements. Scan quality was classified as either good, moderate, or poor. RESULTS: Distribution of good, moderate, and poor quality scans was; CCTA; 66%, 22%, 13%; SPECT; 52%, 38%, 9%; PET; 86%, 13%, 1%. Good quality CCTA scans possessed a higher specificity (75% vs. 31%, p = 0.001), positive predictive value (PPV, 71% vs. 51%, p = 0.050), and accuracy (80% vs. 60%, p = 0.009) compared to moderate quality scans, while sensitivity (94%) and negative predictive value (NPV, 88%) were similar to moderate and poor quality scans. Sensitivity (76%), NPV (84%), and accuracy (85%) of good quality SPECT scans was superior to those of moderate (41% p = 0.001, 56% p = 0.010, 70% p = 0.010) and poor quality (30% p = 0.003, 65% p = 0.069, 63% p = 0.038). Specificity (92%) and PPV (87%) of good quality SPECT scans did not differ from scans of diminished quality. Good quality PET scans exhibited high sensitivity (84%), specificity (86%), NPV (88%), PPV (81%) and accuracy (85%), which was comparable to scans of lesser quality. Good quality CCTA, SPECT, and PET scans demonstrated a similar diagnostic accuracy (p = 0.247). CONCLUSION: Diagnostic performance of CCTA, and SPECT is hampered by scan quality, while the diagnostic value of PET is not affected. Good quality CCTA, SPECT, and PET scans possess a high diagnostic accuracy.


Assuntos
Angiografia por Tomografia Computadorizada , Angiografia Coronária , Reserva Fracionada de Fluxo Miocárdico , Tomografia Computadorizada Multidetectores , Isquemia Miocárdica/diagnóstico por imagem , Imagem de Perfusão do Miocárdio , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia Computadorizada de Emissão de Fóton Único , Idoso , Ensaios Clínicos como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/fisiopatologia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
13.
Urologe A ; 59(1): 65-71, 2020 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-31741004

RESUMO

Due to a safety alert issued by the US Food and Drug Administration (FDA) in 2011 for transvaginal mesh implants to treat female prolapse as a result of numerous reports of complications such as infection, chronic pain, dyspareunia, vaginal erosion, shrinkage and erosion into other organs nearly all industrial products have been withdrawn from the market in the meantime. The United Kingdom, Australia, and New Zealand extended warnings and prohibitions even on the implantation of midurethral slings (TVT, TOT). In view of these current international controversies regarding the use of implanted materials for the treatment of stress incontinence and prolapse and the lack of clear guidelines for the use of biomaterials, the opinion of the Working Group on Urological Functional Diagnostics and Female Urology should provide clarity. The Opinion is based on the SCENIHR Report of the "European Commission's Scientific Committee on Emerging and Newly Identified Health Risks", the "Consensus Statement of the European Urology Association and the European Urogynaecological Association on the Use of Implanted Materials for Treating Pelvic Organ Prolapse and Stress Urinary Incontinence" and in compliance with relevant EAU and national guidelines and the opinion of the Association for Urogynaecology and Plastic Pelvic Floor Reconstruction (AGUB eV). In addition, recommendations are given for the future handling of implants of slings and meshes for the treatment of stress incontinence and prolapse from a urologic viewpoint.


Assuntos
Prolapso de Órgão Pélvico/cirurgia , Slings Suburetrais/efeitos adversos , Telas Cirúrgicas/efeitos adversos , Incontinência Urinária por Estresse/cirurgia , Procedimentos Cirúrgicos Urológicos/instrumentação , Feminino , Alemanha , Humanos
15.
Data Brief ; 27: 104584, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31687432

RESUMO

Scan quality directly impacts the diagnostic performance of non-invasive imaging modalities as reported in a substudy of the PACIFC-trial: "Impact of Scan Quality on the Diagnostic Performance of CCTA, SPECT, and PET for Diagnosing Myocardial Ischemia Defined by Fractional Flow Reserve" [1]. This Data-in-Brief paper supplements the hereinabove mentioned article by presenting the diagnostic performance of CCTA, SPECT, and PET on a per vessel level for the detection of hemodynamic significant coronary artery disease (CAD) when stratified according to scan quality and vascular territory.

16.
Urologe A ; 58(11): 1313-1323, 2019 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-31659368

RESUMO

In this review article, the authors describe all relevant aspects of the new S2k guideline from the German Society of Urology (Deutschen Gesellschaft für Urologie, DGU) for the diagnosis and treatment of IC/PBS (interstitial cystitis/painful bladder syndrome). A list of necessary and optional examinations and the necessity of diagnosis of exclusion are summarized and evaluated. The treatment options listed (ranging from conservative, oral drug, and complementary medicine to interventional surgical procedures) also give the reader a good overview of the contents of the guideline and possible therapeutic approaches. Finally, the recommendations including consensus of the guideline group are also summarized in various information boxes.


Assuntos
Cistite Intersticial/diagnóstico , Cistite Intersticial/terapia , Guias de Prática Clínica como Assunto , Urologia/normas , Alemanha , Humanos , Dor , Exame Físico , Sociedades Médicas
17.
J Cardiovasc Comput Tomogr ; 13(4): 179-187, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31302027

RESUMO

BACKGROUND: A diminished coronary lumen volume to left ventricle mass ratio (V/M) derived from coronary computed tomography angiography (CCTA) has been proposed as factor contributing to impaired myocardial blood flow (MBF) even in the absence of obstructive disease on invasive coronary angiography (ICA). METHODS: Patients underwent CCTA, and positron emission tomography (PET) prior to ICA. Matched global V/M, global, and vessel specific hyperaemic MBF (hMBF), coronary flow reserve (CFR), and, FFR were available for 431 vessels in 152 patients. The median V/M (20.71 mm3/g) was used to divide the population into patients with either a low V/M or a high V/M. RESULTS: Overall, a higher percentage of vessels with an abnormal hMBF and FFR (34% vs. 19%, p = 0.009 and 20% vs. 9%, p = 0.004), as well as a lower FFR (0.93 [interquartile range: 0.85-0.97] vs. 0.95 [0.89-0.98], p = 0.016) values were observed in the low V/M group. V/M was weakly associated with vessel specific hMBF (R = 0.148, p = 0.027), and FFR (R = 0.156, p < 0.001). Among vessels with non-obstructive CAD on ICA (361 vessels), no association between V/M and vessel specific hMBF nor CFR was noted. However, in the absence of obstructive CAD, V/M was associated with (R = 0.081, p = 0.027), and independently predictive for FFR (p = 0.047). CONCLUSION: Overall, an abnormal vessel specific hMBF and FFR were more prevalent in patients with a low V/M compared to those with a high V/M. Furthermore, V/M was weakly associated with vessel specific hMBF and FFR. In the absence of obstructive CAD on ICA, V/M was weakly associated with notwithstanding independently predictive for FFR.


Assuntos
Angiografia por Tomografia Computadorizada , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Reserva Fracionada de Fluxo Miocárdico , Ventrículos do Coração/diagnóstico por imagem , Idoso , Ensaios Clínicos como Assunto , Doença da Artéria Coronariana/fisiopatologia , Vasos Coronários/fisiopatologia , Feminino , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes
18.
Eur J Nucl Med Mol Imaging ; 45(7): 1091-1100, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29470616

RESUMO

PURPOSE: Traditionally, interpretation of myocardial perfusion imaging (MPI) is based on visual assessment. Computer-based automated analysis might be a simple alternative obviating the need for extensive reading experience. Therefore, the aim of the present study was to compare the diagnostic performance of automated analysis with that of expert visual reading for the detection of obstructive coronary artery disease (CAD). METHODS: 206 Patients (64% men, age 58.2 ± 8.7 years) with suspected CAD were included prospectively. All patients underwent 99mTc-tetrofosmin single-photon emission computed tomography (SPECT) and invasive coronary angiography with fractional flow reserve (FFR) measurements. Non-corrected (NC) and attenuation-corrected (AC) SPECT images were analyzed both visually as well as automatically by commercially available SPECT software. Automated analysis comprised a segmental summed stress score (SSS), summed difference score (SDS), stress total perfusion deficit (S-TPD), and ischemic total perfusion deficit (I-TPD), representing the extent and severity of hypoperfused myocardium. Subsequently, software was optimized with an institutional normal database and thresholds. Diagnostic performances of automated and visual analysis were compared taking FFR as a reference. RESULTS: Sensitivity did not differ significantly between visual reading and most automated scoring parameters, except for SDS, which was significantly higher than visual assessment (p < 0.001). Specificity, however, was significantly higher for visual reading than for any of the automated scores (p < 0.001 for all). Diagnostic accuracy was significantly higher for visual scoring (77.2%) than for all NC images scores (p < 0.05), but not compared with SSS AC and S-TPD AC (69.8% and 71.2%, p = 0.063 and p = 0.134). After optimization of the automated software, diagnostic accuracies were similar for visual (73.8%) and automated analysis. Among the automated parameters, S-TPD AC showed the highest accuracy (73.5%). CONCLUSION: Automated analysis of myocardial perfusion SPECT can be as accurate as visual interpretation by an expert reader in detecting significant CAD defined by FFR.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Imagem de Perfusão do Miocárdio , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Automação , Angiografia Coronária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
Phys Rev Lett ; 119(11): 113903, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28949243

RESUMO

Applications of the orbital angular momentum (OAM) of light range from the next generation of optical communication systems to optical imaging and optical manipulation of particles. Here we propose a micron-sized semiconductor source that emits light with predefined OAM pairs. This source is based on a polaritonic quantum fluid. We show how in this system modulational instabilities can be controlled and harnessed for the spontaneous formation of OAM pairs not present in the pump laser source. Once created, the OAM states exhibit exotic flow patterns in the quantum fluid, characterized by generation-annihilation pairs. These can only occur in open systems, not in equilibrium condensates, in contrast to well-established vortex-antivortex pairs.

20.
BMC Nephrol ; 18(1): 149, 2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28464802

RESUMO

BACKGROUND: Vascular calcification is a major contributing factor to mortality in end stage renal disease (ESRD). Despite the efficacy of phosphate binders to improve hyperphosphatemia, data on vascular calcification are less clear. There seems to be a difference in attenuation or delay in progression between different binders. In this in vitro experiment we tested whether phosphate binders could limit bioavailability of vitamin K2 by undesired binding. Vitamin K-deficiency limits activation of the vascular tissue mineralization inhibitor matrix γ-carboxyglutamate (Gla) protein (MGP) thereby exacerbating vascular calcification. METHODS: In this experiment vitamin K2 (menaquinone-7; MK-7) binding was assessed by adding 1 mg of vitamin K2 to a medium with pH 6 containing 67 mg phosphate binder with either 7 mg of phosphate or no phosphate. Five different phosphate binders were tested. After five and a half hours vitamin K was analyzed by HPLC. All experiments were performed in triplicate. RESULTS: Sucroferric-oxyhydroxide and sevelamer carbonate did not significantly bind vitamin K2, both in solution only containing vitamin K2 or in combination with phosphate. Calcium acetate/magnesium carbonate binds vitamin K2 strongly both in absence (p = 0.001) and presence of phosphate (p = 0.003). Lanthanum carbonate significantly binds vitamin K2 in solution containing only vitamin K2 (p = 0.005) whereas no significant binding of vitamin K2 was observed in the solution containing vitamin K2 and phosphate (p = 0.462). Calcium carbonate binds vitamin K2 significantly in a solution with vitamin K2 and phosphate (p = 0.009) whereas without phosphate no significant binding of vitamin K2 was observed (p = 0.123). CONCLUSIONS: Sucroferric-oxyhydroxide and sevelamer carbonate were the only binders of the five binders studied that did not bind vitamin K2 in vitro. The presence or absence of phosphate significantly interferes with vitamin K2 binding so phosphate binders could potentially limit bioavailability vitamin K2.


Assuntos
Quelantes/química , Fosfatos/química , Vitamina K/química , Ligação Proteica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...