Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 53
Filtrar
1.
Chemistry ; 30(37): e202400623, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38656599

RESUMO

The emergent properties resulting from selective supramolecular interactions are of significant importance for materials and chemical systems. For the directed use of such properties, a fundamental understanding of the interaction mechanism and the resulting mode of function is necessary for a tailored design. The self-induced diastereomeric anisochronism effect (SIDA), which occurs in the intermolecular interaction of chiral molecules, generates unique properties such as chiral self-recognition and nonlinear effects. Here we show that anisidine amino acid diamides lead to extraordinary signal splitting in NMR spectra through supramolecular interaction and homochiral self-recognition. By systematic experiments we have investigated the underlying SIDA effect, explored its limits and finally successfully utilized it in the determination of enantiomeric ratios by NMR spectroscopy of chiral 'SIDA-inactive' compounds such as thalidomide.

2.
N Engl J Med ; 380(19): 1834-1842, 2019 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-31067372

RESUMO

Mesenchymal hamartoma of the liver (MHL) is a benign tumor affecting children that is characterized by a primitive myxoid stroma with cystically dilated bile ducts. Alterations involving chromosome 19q13 are a recurrent underlying cause of MHL; these alterations activate the chromosome 19 microRNA cluster (C19MC). Other cases remain unexplained. We describe two children with MHLs that harbored germline DICER1 pathogenic variants. Analysis of tumor tissue from one of the children revealed two DICER1 "hits." Mutations in DICER1 dysregulate microRNAs, mimicking the effect of the activation of C19MC. Our data suggest that MHL is a new phenotype of DICER1 syndrome. (Funded by the Canadian Institutes of Health Research and others.).


Assuntos
Cromossomos Humanos Par 19 , RNA Helicases DEAD-box/genética , Mutação em Linhagem Germinativa , Hamartoma/genética , Hepatopatias/genética , MicroRNAs/metabolismo , Síndromes Neoplásicas Hereditárias/genética , Ribonuclease III/genética , Pré-Escolar , Feminino , Predisposição Genética para Doença , Hamartoma/diagnóstico por imagem , Hamartoma/patologia , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Hepatopatias/diagnóstico por imagem , Hepatopatias/patologia , Masculino , Mesoderma , Linhagem , Fenótipo
3.
J Org Chem ; 87(16): 11165-11171, 2022 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-35939525

RESUMO

For the preparation of chiral drugs, both stereochemically stable and flexible catalysts in combination with chiral auxiliaries can be used. Here, chiral induction plays an important role in generating an enantiomerically pure catalyst. We demonstrate a successful approach to the spontaneous deracemization of tropos ligands for asymmetric catalysis. Three different constitutional isomers of a bisphosphinite ligand decorated with l-valine moieties (interaction units) linked to the flexible biphenyl system by a phenylene bridge for inducing a chiral switch were prepared. The substitution pattern's influence on the attached intermolecular recognition sites was systematically investigated. We can show that biomimetic intramolecular hydrogen bonding leads to a pronounced diastereoselective enrichment of one of the ligand stereoisomers. As a result, in the asymmetric Rh-catalyzed hydrogenation of prochiral olefins using these ligands, enantiomeric ratios of up to 95.8:4.2 (S) were obtained. Of particular note is the inversion of enantioselectivity relative to the previously reported BIBIPHOS-Rh catalyst due to the altered orientation of the biphenyl moiety from (Rax) to (Sax). The enantioselectivities achieved by appropriate intramolecular interlocking are remarkable for a tropos ligand/catalyst. The strategy presented here represents a powerful approach for the spontaneous alignment of tropos ligands, yielding high enantioselectivities in asymmetric catalysis.


Assuntos
Biomimética , Catálise , Hidrogenação , Ligantes , Estereoisomerismo
4.
Vascular ; 26(1): 99-110, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28820357

RESUMO

Objectives The aim of this study was to investigate the possible benefits from computed tomography scans of patients with a suspected pulmonary artery embolism with a focus on relevant extravascular findings. Methods A total of 400 consecutive computed tomography pulmonary angiographies were evaluated. Computed tomography scans were analyzed in detail for the presence of pulmonary artery embolisms, as well as any other findings. Extra-artery discoveries were classified into none-relevant (Group A), intermediate (Group B), or relevant (Group C) findings. Results Aggregated computed tomography pulmonary angiographies detected other diagnosis than pulmonary artery embolism in 236 patients (59%). There were 1950 non-pulmonary artery embolism findings (4.9 per patient; n = 397). In the pulmonary artery embolism group, there were 447 extra-pulmonary artery embolism findings (5.2 per patient; n = 86) and in the non-pulmonary artery embolism group, 1503 findings (4.8 per patient; n = 311). Patients with pulmonary artery embolism had a significantly higher rate of pro-coagulate risk factors ( p < 0.001). Conclusions Computed tomography pulmonary angiographies may help to identify further diagnoses. This study represents a retrospective review of a single center experience for incidental computed tomography findings during pulmonary artery embolism work-up and emphasizes the importance of analyzing the whole field-of-view.


Assuntos
Angiografia por Tomografia Computadorizada , Achados Incidentais , Tomografia Computadorizada Multidetectores , Artéria Pulmonar/diagnóstico por imagem , Embolia Pulmonar/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Embolia Pulmonar/sangue , Estudos Retrospectivos
5.
Vascular ; 26(1): 27-38, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28587578

RESUMO

Background The aim of this study was to assess the prevalence and clinical significance of extra-vascular findings in patients undergoing magnetic resonance angiography of the abdomen, pelvis and lower extremities. Materials and methods Three hundred fifty-two patients underwent abdominal, pelvic and lower extremity 1.5 T magnetic resonance angiography. Clinically relevant vascular and extra-vascular findings were identified. Relevant vascular findings were classified as stenosis, occlusion, aneurysm, sclerosis, dissection or vasculitis. Relevant extra-vascular findings were categorized as 'safe' (Group A), intermediate - requiring additional investigation - (Group B) and malignant/endangering - requiring change of therapy (Group C). Results A total of 2152 clinically relevant vascular findings was identified (6.1/patient). The most frequent vascular finding was femoral artery stenosis (10.6%). Four hundred fifty-one extra-vascular findings were observed (1.3/patient) and classified into Group A (78%), Group B (19.5%) and Group C findings (2.4%). The most frequent malignant findings were lung cancer, lymphoma, osteosarcoma, hepatocellular carcinoma and renal cell carcinoma (7/352 patients). Conclusions Extravascular findings are frequently encountered in magnetic resonance angiography performed for vascular indications. Clinically relevant findings are seen in a substantial part of patients and should prompt further diagnostic work-up.


Assuntos
Abdome/irrigação sanguínea , Achados Incidentais , Extremidade Inferior/irrigação sanguínea , Angiografia por Ressonância Magnética , Neoplasias/diagnóstico por imagem , Pelve/irrigação sanguínea , Doenças Vasculares/diagnóstico por imagem , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos
6.
Eur Radiol ; 26(2): 451-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25991489

RESUMO

OBJECTIVES: To meta-analyze diagnostic accuracy, test yield and utility of coronary computed tomography angiography (CCTA) in coronary artery disease (CAD) by an intention-to-diagnose approach with inclusion of unevaluable results. METHODS: Four databases were searched from 1/2005 to 3/2013 for prospective studies that used 16-320-row or dual-source CTs and provided 3 × 2 patient-level data of CCTA (positive, negative, or unevaluable) versus catheter angiography (positive or negative) for diagnosing ≥50% coronary stenoses. A Bayesian multivariate 3 × 2 random-effects meta-analysis considered unevaluable CCTAs. RESULTS: Thirty studies (3422 patients) were included. Compared to 16-40 row CT, test yield and accuracy of CCTA has significantly increased with ≥64-row CT (P < 0.05). In ≥64-row CT, about 2.5% (95%-CI, 0.9-4.8%) of diseased patients and 7.5% (4.5-11.2%) of non-diseased patients had unevaluable CCTAs. A positive likelihood ratio of 8.9 (6.1-13.5) indicated moderate suitability for identifying CAD. A negative likelihood ratio of 0.022 (0.01-0.04) indicated excellent suitability for excluding CAD. Unevaluable CCTAs had an equivocal likelihood ratio of 0.42 (0.22-0.71). In the utility analysis, CCTA was useful at intermediate pre-test probabilities (16-70%). CONCLUSIONS: CCTA is useful at intermediate CAD pre-test probabilities. Positive CCTAs require verification to confirm CAD, unevaluable CCTAs require alternative diagnostics, and negative CCTAs exclude obstructive CAD with high certainty. KEY POINTS: • This 3 × 2 Bayesian meta-analysis included unevaluable CCTAs with intention-to-diagnose. • CCTA is currently useful at intermediate CAD pre-test probabilities. • Unevaluable CCTAs should not, generally, be treated as if they are positive. • Positive CCTAs require verification by other methods to confirm CAD. • Negative CCTAs exclude CAD with high certainty.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Teorema de Bayes , Angiografia Coronária/normas , Humanos , Intenção , Estudos Prospectivos , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/normas
7.
Chirality ; 28(11): 744-748, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27791317

RESUMO

Stereodynamic ligands and complexes bearing functional groups to attach chiral or achiral binding sites and auxiliaries are highly attractive due to the interesting opportunities for controlling the stereochemical outcome of enantioselective transformations. In this study we report the preparation of a 3,3'-functionalized biphenol (BIPOL) phosphoramidite ligand (PAm ) bearing 3,5-dichlorobenzoyl (3,5-DCB) amide binding sites for noncovalent interactions. Upon coordination to [Rh(COD)2 ]BF4 this substitution pattern directs one of the 3,5-DCB binding sites in close proximity of the metal center resulting in liberation of both COD ligands and the formation of a [Rh(PAm )2 ]BF4 complex. Coordination of the amide carbonyl unit was found to be reversible, since the complex acted as an active catalyst in the hydrogenation of dehydroamino acid derivatives. X-ray crystallographic investigation revealed that the second 3,5-DCB unit is capable of forming noncovalent π-π interactions connecting both phosphoramidite ligands.

8.
Eur Radiol ; 25(8): 2205-13, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25721319

RESUMO

OBJECTIVES: Photoacoustic breast tomography could provide optical molecular imaging with near-infrared light at sonographic image resolution by utilizing the photoacoustic effect. This review summarizes reports about current prototypes that were applied in vivo in humans. METHODS: Four databases were searched for reports about prototypes of photoacoustic breast tomography that were tested in vivo in humans. Data extracted from the reports comprised details about system design, phantom studies, and clinical studies. RESULTS: Five prototypes were included. System designs comprised planar, hemicylindrical and hemispherical geometries. In total, 52 of 61 breast cancers (85 %) were detected by three of the prototypes, showing image details such as ring-pattern of the haemoglobin-rich tumour vasculature. A refined prototype provided submillimetre resolution at a good contrast-to-noise ratio up to a depth of about 5 cm in a cup-shaped breast configuration. Another novel prototype demonstrated that in the mammographic imaging geometry, the total imaging depth approximately duplicates with bilateral laser illumination. Most prototypes focused on detecting elevated haemoglobin content related to tumours, but proof-of-principle was also given for multispectral optoacoustic tomography by additional imaging of tissue oxygenation. CONCLUSIONS: Photoacoustic breast tomography can detect breast cancer. This radiation-free molecular imaging technology should be further refined and studied for clinical applications. KEY POINTS: • Photoacoustics combines optical imaging with sonographic signal detection. • Photoacoustic tomography could provide molecular imaging at high image resolution. • Prototypes have been designed for human breast cancer imaging. • Preliminary evaluation studies show that photoacoustic tomography detects breast cancer. • This radiation-free method should be further improved and studied for clinical applications.


Assuntos
Neoplasias da Mama/diagnóstico , Técnicas Fotoacústicas/instrumentação , Tomografia/instrumentação , Desenho de Equipamento , Feminino , Hemoglobinas/metabolismo , Humanos , Raios Infravermelhos , Mamografia/instrumentação , Mamografia/métodos , Imagem Molecular/instrumentação , Imagem Molecular/métodos , Imagens de Fantasmas , Técnicas Fotoacústicas/métodos , Decúbito Ventral , Análise Espectral , Tomografia/métodos
9.
Eur J Pediatr ; 174(3): 307-16, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25132464

RESUMO

UNLABELLED: In children with ileocolic intussusception sonography is increasingly being used for diagnosis, whereas fluoroscopy is frequently used for guiding non-invasive reduction. This study assessed the success rate of radiation-free sonography-guided hydrostatic reduction in children with ileocolic intussusception, using novel well-defined success rate indices. All children were evaluated who presented from 2005 to 2013 to the local university hospital with ileocolic intussusception. The patients were treated with sonography-guided hydrostatic reduction unless primary surgery was clinically indicated. The according success rate was determined by indices of Bekdash et al. They represent the ratio of persistently successful non-surgical reductions versus four different denominators, depending on including/excluding cases with primary surgery and including/excluding cases requiring bowel resection/intervention. Fifty-six consecutive patients were included (age, 3 months to 7.8 years). About 80% of the patients presented until 24 h and 20% until 48 h after the onset of symptoms. Seven patients underwent primary surgery, with bowel resection required in three cases. Hydrostatic reduction was attempted in 49 patients, being permanently successful in 41 cases (selective reduction rate 41/49 = 83.7%; crude reduction rate 41/56 = 73.2%). The remaining eight patients underwent secondary surgery, with just two patients not requiring surgical bowel resection/intervention (corrected selective reduction rate 41/43 = 95.3%). The composite reduction rate was 87.2% (successful/feasible reductions, 41/47). CONCLUSION: Radiation-free sonography-guided hydrostatic reduction has a good success rate in children with ileocolic intussusception. It may be particularly valuable in centers that are already experienced with using sonography for the diagnosis.


Assuntos
Enema/métodos , Pressão Hidrostática , Doenças do Íleo/terapia , Intussuscepção/terapia , Ultrassonografia/métodos , Criança , Pré-Escolar , Feminino , Humanos , Doenças do Íleo/diagnóstico por imagem , Lactente , Intussuscepção/diagnóstico por imagem , Masculino , Falha de Tratamento , Resultado do Tratamento
10.
J Magn Reson Imaging ; 39(1): 68-76, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23589475

RESUMO

PURPOSE: To assess the incidence of extracardiac findings in patients undergoing clinical cardiac magnetic resonance imaging (CMRI) of the heart, and to determine the influence of those findings on patient management. MATERIALS AND METHODS: During 40 months, 854 CMRI were performed at 1.5 T. Extracardiac findings were classified as significant (group A), if recommended for additional diagnostics or therapeutic interventions, and as nonsignificant (group B). RESULTS: The most frequent indication for CMRI was evaluation of cardiac stress ischemia. In all, 631 CMRI (74% of 854) showed no extracardiac pathologies. In the remaining 223 CMRI (26% of 854), a total of 286 extracardiac findings were detected. Among these findings, 49 were considered significant (group A) and 237 nonsignificant (group B). In group A, the most common findings were suspicious pulmonary nodules or masses. In group B, the most frequent findings were hepatic cysts or hemangiomas. Eight malignancies were observed with certainty at CMRI. Seven of them had been incidentally diagnosed on CMRI for the first time, and subsequently changed the patients' management. CONCLUSION: Extracardiac findings in clinically indicated CMRI are common (about 26%). Radiologists and cardiologists should be aware of relevant extracardiac findings that might require additional diagnostics or treatment.


Assuntos
Imageamento por Ressonância Magnética , Isquemia Miocárdica/diagnóstico , Miocárdio/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Aneurisma Aórtico/diagnóstico , Criança , Pré-Escolar , Estudos de Coortes , Meios de Contraste/química , Cistos/diagnóstico , Feminino , Hemangioma/diagnóstico , Humanos , Achados Incidentais , Lactente , Hepatopatias/diagnóstico , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade , Nódulos Pulmonares Múltiplos/diagnóstico , Isquemia Miocárdica/complicações , Derrame Pleural/diagnóstico , Pneumonia/diagnóstico , Prevalência , Estudos Retrospectivos , Adulto Jovem
11.
J Magn Reson Imaging ; 40(4): 988-95, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24740558

RESUMO

PURPOSE: To investigate the presence of relevant vascular and incidental extravascular findings in patients undergoing magnetic resonance angiography (MRA) of the thoracic aorta and origin of the great vessels. MATERIALS AND METHODS: In all, 165 consecutive patients (mean age 61 ± 12 years) underwent 1.5 T MRA of the thorax. Two researchers identified vascular and incidental extravascular findings. Clinically relevant vascular findings were defined. Extravascular findings were categorized as minor (Group A, without change in patient treatment), intermediate (Group B, unclear clinical relevance, requiring additional investigations), and major (Group C, causing a change in patient treatment). RESULTS: A total of 306 relevant vascular findings were found in our cohort. A total of 397 extravascular findings were observed among the patients and were classified as Group A findings in 81.9% (325/397 findings, observed in 146 of 165 patients), as Group B findings in 15.4% (61/397 findings, observed in 52 of 165 patients), and as Group C in 2.8% of findings (11/397). The clinically relevant Group C findings were observed in 6.7% of patients (11/165), comprising eight previously unknown neoplasms (4.8% of 165), two patients with hemodynamically relevant pericardial effusion (1.2% of 165), and one patient with spondylodiscitis (0.6% of 165) detected by MRA. CONCLUSION: Relevant vascular and extravascular findings were found in patients referred for thoracic MRA. Most extravascular findings can be categorized by MRA as minor, while others required further diagnostics since they may be malignant or otherwise clinically relevant.


Assuntos
Aorta Torácica/patologia , Angiografia por Ressonância Magnética/métodos , Angiografia por Ressonância Magnética/estatística & dados numéricos , Doenças Torácicas/epidemiologia , Doenças Torácicas/patologia , Doenças Vasculares/epidemiologia , Doenças Vasculares/patologia , Feminino , Alemanha/epidemiologia , Humanos , Incidência , Achados Incidentais , Masculino , Pessoa de Meia-Idade
12.
Infection ; 42(2): 415-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23955269

RESUMO

A 13-year-old girl with weight loss and ascites was admitted with suspicion of a malignant disease. Abdominal magnetic resonance imaging indicated extensive peritonitis and showed no evidence of a solid tumor. As a new imaging observation, thoracic computed tomography showed a lymphoma-like infracarinal mass and further enlarged lymph nodes in the pathway of draining lymph ducts. A tuberculin skin test and an interferon-gamma blood test were positive, and the tumor marker CA-125 was elevated. Histology of a peritoneal biopsy showed infectious granulomas with central necrosis, and Mycobacterium tuberculosis could be cultured, leading to the diagnosis of a tuberculous peritonitis. The girl received multi-drug anti-tuberculous treatment and subsequently recovered. At follow-up the peritonitis and the infracarinal mass had vanished. In conclusion, tuberculous peritonitis is a rare but relevant differential diagnosis in peritonitis of unknown origin. Its diagnosis is facilitated by imaging, by tuberculosis skin and blood tests, and by clinical interpretation.


Assuntos
Antituberculosos/uso terapêutico , Antígeno Ca-125/sangue , Linfonodos/microbiologia , Mycobacterium tuberculosis/isolamento & purificação , Peritonite Tuberculosa/tratamento farmacológico , Peritonite Tuberculosa/microbiologia , Adolescente , Diagnóstico Diferencial , Feminino , Humanos , Interferon gama/sangue , Linfonodos/patologia , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Teste Tuberculínico
13.
Pediatr Cardiol ; 35(1): 155-63, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23852460

RESUMO

Near-infrared spectroscopy (NIRS) can monitor changes in cerebral regional oxygen saturation (rSO2) and tissue hemoglobin content (HbT). The relation between cerebral NIRS readings and vital parameters has not been analyzed before at a fine temporal scale. This study analyzed this relation during cardiopulmonary bypass (CPB) surgery in 10 children (0-9 years, 1,770 min of data records) by using a novel random-coefficient model. The analysis indicated that a small number of patients is sufficient for obtaining significant results with this model. Changes of vital parameters explained 84.7 % of rSO2 changes and 90.7 % of HbT changes. Cerebral rSO2 correlated positively with perfusion pressure and inversely with body temperature (P < 0.05). Cerebral HbT correlated positively with perfusion pressure, central venous pressure, and temperature and inversely with arterial oxygen saturation (P < 0.05). During hypothermic circulatory arrest, the half-life of the exponential rSO2 decay correlated to the rSO2 reserve (P = 0.016). In conclusion, NIRS readings of cerebral hemoglobin content and tissue oxygen saturation correlate well to vital parameters during CPB surgery in children. NIRS may therefore become a monitoring device for the neuroprotective optimization of those vital parameters.


Assuntos
Ponte Cardiopulmonar , Cardiopatias Congênitas/cirurgia , Hipotermia Induzida , Doenças do Sistema Nervoso/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Encéfalo/metabolismo , Ponte Cardiopulmonar/efeitos adversos , Ponte Cardiopulmonar/métodos , Circulação Cerebrovascular , Criança , Pré-Escolar , Feminino , Alemanha , Hemoglobinas/metabolismo , Humanos , Hipotermia Induzida/efeitos adversos , Hipotermia Induzida/métodos , Lactente , Recém-Nascido , Masculino , Modelos Estatísticos , Monitorização Intraoperatória/métodos , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/metabolismo , Doenças do Sistema Nervoso/fisiopatologia , Oxigênio/análise , Consumo de Oxigênio , Complicações Pós-Operatórias/metabolismo , Complicações Pós-Operatórias/fisiopatologia , Estatística como Assunto , Sinais Vitais
14.
J Phys Ther Sci ; 26(7): 997-1002, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25140082

RESUMO

[Purpose] A wide variety of accelerometer tools are used to estimate human movement, but there are no adequate data relating to gait symmetry parameters in the context of knee osteoarthritis. This study's purpose was to evaluate a 3D-kinematic system using body-mounted sensors (gyroscopes and accelerometers) on the trunk and limbs. This is the first study to use spectral analysis for data post processing. [Subjects] Twelve patients with unilateral knee osteoarthritis (OA) (10 male) and seven age-matched controls (6 male) were studied. [Methods] Measurements with 3-D accelerometers and gyroscopes were compared to video analysis with marker positions tracked by a six-camera optoelectronic system (VICON 460, Oxford Metrics). Data were recorded using the 3D-kinematic system. [Results] The results of both gait analysis systems were significantly correlated. Five parameters were significantly different between the knee OA and control groups. To overcome time spent in expensive post-processing routines, spectral analysis was performed for fast differentiation between normal gait and pathological gait signals using the 3D-kinematic system. [Conclusions] The 3D-kinematic system is objective, inexpensive, accurate and portable, and allows long-term recordings in clinical, sport as well as ergonomic or functional capacity evaluation (FCE) settings. For fast post-processing, spectral analysis of the recorded data is recommended.

15.
Am Heart J ; 165(2): 154-63.e3, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23351817

RESUMO

BACKGROUND: In coronary computed tomography (CT) angiography (CTA) prospective electrocardiography triggering requires less radiation dose than retrospective electrocardiography gating but provides less cardiac phases for interpretation. This meta-analysis presents a concise and comprehensive head-to-head comparison of image quality, diagnostic accuracy, and radiation dose of prospectively triggered coronary CTA vs retrospectively gated CTA in patients with suspected or known coronary artery disease (CAD). METHODS: In patients with CAD and without tachyarrhythmia, eligible studies (selected from 4 databases) compared prospectively triggered vs retrospectively gated CTA (performed with ≥64-slice CT or dual-source CT) in 2 groups having approximately similar patient characteristics, scored CTA image quality, and/or assessed how accurately CTA diagnoses ≥50% coronary stenoses compared with catheter angiography and reported the radiation dose. The data were meta-analyzed by random-effects models, with CIs provided in the text. RESULTS: Among 3,330 patients from 20 included studies, 91.3% of CTAs (segments: 97.8%) had diagnostic quality with prospective triggering and 93.3% of CTAs (segments: 98.4%) with retrospective gating (P > .05). Among 664 patients from 5 studies, the pooled sensitivity/specificity of diagnostic CTAs was 98.7%/91.3% (segment level: 91.3%/97.7%) with prospective triggering and 96.9%/95.8% (segment level: 93.1%/97.6%) with retrospective gating (P > .05). The pooled effective dose was 3.5 mSv with prospective triggering and thus, by a factor of 3.5, lower than the pooled effective dose of retrospective gating, which was 12.3 mSv (P < .01). CONCLUSIONS: In patients with CAD and without tachyarrhythmia, prospectively triggered coronary CTA provides image quality and diagnostic accuracy comparable with retrospectively gated CTA, but at a much lower radiation dose.


Assuntos
Angiografia Coronária/normas , Doença da Artéria Coronariana/diagnóstico por imagem , Doses de Radiação , Tomografia Computadorizada por Raios X , Angiografia Coronária/métodos , Humanos , Estudos Prospectivos , Reprodutibilidade dos Testes , Estudos Retrospectivos
16.
Ann Neurol ; 69(4): 646-54, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21391230

RESUMO

OBJECTIVE: Cerebral aneurysms can cause substantial morbidity and mortality, specifically if they rupture, leading to nontraumatic subarachnoid hemorrhage (SAH). This meta-analysis summarizes evidence about the accuracy of noninvasive computed tomographic (CT) angiography for diagnosing intracranial aneurysms in symptomatic patients. METHODS: Four databases including PubMed were searched without language restrictions from January 1995 to February 2010. Two independent reviewers selected and extracted 45 studies that compared CT angiography with digital subtraction angiography (DSA) and/or intraoperative findings in patients suspected of having cerebral aneurysms. Data from eligible studies were used to reconstruct 2 x 2 contingency tables on a per-patient basis in at least 5 diseased and 5 nondiseased patients, with additional data on a per-aneurysm basis when available. RESULTS: The 45 included studies generally were of high methodological quality. Among the 3,643 patients included, about 86% had nontraumatic SAH, and 77% had cerebral aneurysms. Overall, CT angiography had a pooled sensitivity of 97.2% (95% confidence interval, 95.8-98.2%) for detecting and specificity of 97.9% (95.7-99.0%) for ruling out cerebral aneurysms on a per-patient basis. On a per-aneurysm basis, the pooled sensitivity was 95.0% (93.2-96.4%), and the specificity 96.2% (92.9-98.0%). The diagnostic accuracy of CT angiography with 16- or 64-row multidetector CT was significantly higher than that of single-detector CT, especially in detecting small aneurysms of ≤ 4 mm in diameter. INTERPRETATION: CT angiography has a high accuracy in diagnosing cerebral aneurysms, specifically when using modern multidetector CT. In the future, CT angiography may increasingly supplement or selectively replace DSA in patients suspected of having a cerebral aneurysm.


Assuntos
Angiografia/instrumentação , Aneurisma Intracraniano/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Angiografia Digital , Fatores de Confusão Epidemiológicos , Medicina Baseada em Evidências , Humanos , Variações Dependentes do Observador , Sensibilidade e Especificidade
17.
BMC Cancer ; 12: 424, 2012 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-23006472

RESUMO

BACKGROUND: Pulmonary carcinosarcoma is a biphasic tumour with an unfavourable prognosis. The differential diagnosis includes pulmonary blastoma and is often challenging. CASE PRESENTATION: We here describe a case of blastomatoid pulmonary carcinosarcoma in a 58-year-old patient, who underwent surgical resection. Histopathological examination revealed immature glandular epithelium resembling high-grade fetal adenocarcinoma expressing epithelial markers and membranous beta-catenin, and blastomatoid spindle cells with partial rhabdomyosarcoma-like differentiation. Both elements expressed p53, MDM2, and cyclin-dependent kinase 4 (CDK4), but not thyroid-transcription factor 1 (TTF-1). Mutation analysis of KRAS, EGFR, and beta-catenin revealed no mutations. Comparative genomic hybridization detected +1q, +6p, +6q24qter, +8q, +11q12q14, +11q23qter, +12q12q21, +12q24qter, +17q, +20q, -5q14q23, -9p13pter, -13q21q21, and amplifications at 12q14q21, 15q24qter, 20q11q12. CONCLUSION: The observed molecular and cytogenetic findings may provide additional tools for the differential diagnosis of biphasic pulmonary neoplasms. Furthermore, TP53, MDM2, CDK4, and PTPN1 may be involved in tumourigenesis.


Assuntos
Carcinossarcoma/diagnóstico , Neoplasias Pulmonares/diagnóstico , Pulmão/patologia , Blastoma Pulmonar/diagnóstico , Carcinossarcoma/genética , Carcinossarcoma/metabolismo , Aberrações Cromossômicas , Hibridização Genômica Comparativa , Quinase 4 Dependente de Ciclina/metabolismo , Diagnóstico Diferencial , Humanos , Imuno-Histoquímica , Pulmão/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Blastoma Pulmonar/genética , Blastoma Pulmonar/metabolismo , Proteína Supressora de Tumor p53/metabolismo
18.
Geburtshilfe Frauenheilkd ; 82(2): 181-205, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35197803

RESUMO

Aim This is an update of the interdisciplinary S3-guideline on the Diagnosis, Therapy and Follow-up of Cervical Cancer (AWMF Registry No. 032/033OL), published in March 2021. The work on the updated guideline was funded by German Cancer Aid (Deutsche Krebshilfe) as part of the German Guideline Program in Oncology. The guideline was coordinated by the German Society of Gynecology and Obstetrics ( Deutsche Gesellschaft für Gynäkologie und Geburtshilfe , DGGG) and the Working Group on Gynecological Oncology ( Arbeitsgemeinschaft Gynäkologische Onkologie , AGO) of the German Cancer Society ( Deutsche Krebsgesellschaft , DKG). Method The process used to update the 2014 S3-guideline was based on an appraisal of the available evidence using the criteria of evidence-based medicine, adaptations of existing evidence-based national and international guidelines or - if evidence was lacking - on the consensus of the specialists involved in compiling the update. After an initial review of the current literature was carried out according to a prescribed algorithm, several areas were identified which, in contrast to the predecessor version from September 2014, required new recommendations or statements which would take account of more recently published literature and the recent appraisal of new evidence. Recommendations The short version of this guideline consists of recommendations and statements on palliative therapy and follow-up of patients with cervical cancer. The most important aspects included in this updated guideline are the new FIGO classification published in 2018, the radical open surgery approach used to treat cervical cancer up to FIGO stage IB1, and the use of the sentinel lymph node technique for tumors ≤ 2 cm. Other changes include the use of PET-CT, new options in radiotherapy (e.g., intensity-modulated radiotherapy, image-guided adaptive brachytherapy), and drug therapies to treat recurrence or metastasis.

19.
Geburtshilfe Frauenheilkd ; 82(2): 139-180, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35169387

RESUMO

Aim This update of the interdisciplinary S3 guideline on the Diagnosis, Therapy and Follow-up of Cervical Cancer (AWMF Registry No. 032/033OL) was published in March 2021. This updated guideline was funded by German Cancer Aid (Deutsche Krebshilfe) as part of the German Guideline Program in Oncology. The guideline was coordinated by the German Society of Gynecology and Obstetrics ( Deutsche Gesellschaft für Gynäkologie und Geburtshilfe , DGGG) and the Working Group on Gynecological Oncology ( Arbeitsgemeinschaft Gynäkologische Onkologie , AGO) of the German Cancer Society ( Deutsche Krebsgesellschaft , DKG). Method The process of updating the S3 guideline dating from 2014 was based on an appraisal of the available evidence using the criteria of evidence-based medicine, adaptations of existing evidence-based national and international guidelines or - if evidence was lacking - on a consensus of the specialists involved in compiling the update. After an initial review of the current literature was carried out according to a prescribed algorithm, several areas were identified which, in contrast to the predecessor version from September 2014, required new recommendations or statements which took account of more recently published literature and the appraisal of the new evidence. Recommendations The short version of this guideline consists of recommendations and statements on the epidemiology, screening, diagnostic workup and therapy of patients with cervical cancer. The most important new aspects included in this updated guideline include the newly published FIGO classification of 2018, the radical open surgery approach for cervical cancers up to FIGO stage IB1, and use of the sentinel lymph node technique for tumors ≤ 2 cm. Other changes include the use of PET-CT, new options in radiotherapy (e.g., intensity-modulated radiotherapy, image-guided adaptive brachytherapy), and drug therapies to treat recurrence or metastasis.

20.
Ann Intern Med ; 153(5): 325-34, 2010 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-20820041

RESUMO

BACKGROUND: Contrast-enhanced magnetic resonance angiography (MRA) is a noninvasive, radiation-free imaging method for studying peripheral arterial disease (PAD) of the lower extremities. PURPOSE: To summarize evidence of prospective studies about how well MRA identifies or excludes arterial steno-occlusions (50% to 100% lumen reduction) in adults with PAD symptoms. DATA SOURCES: PubMed and 3 other databases were searched from 1998 to 2009 without language restrictions. STUDY SELECTION: Two independent reviewers selected 32 studies that compared MRA with intra-arterial digital subtraction angiography in PAD. Eligible studies were prospective and provided data to reconstruct 2 x 2 or 3 x 3 contingency tables (<50% stenosis vs. > or =50% stenosis or occlusion of arterial segments) in at least 10 patients with PAD symptoms. DATA EXTRACTION: Two reviewers independently assessed the study quality and extracted the study data, with disagreements resolved by consensus. DATA SYNTHESIS: The 32 included studies generally had high methodological quality. About 26% of the 1022 included patients had critical limb ischemia with pain at rest or tissue loss. Overall, the pooled sensitivity of MRA was 94.7% (95% CI, 92.1% to 96.4%) and the specificity was 95.6% (CI, 94.0% to 96.8%) for diagnosing segmental steno-occlusions. The pooled positive and negative likelihood ratios were 21.56 (CI, 15.70 to 29.69) and 0.056 (CI, 0.037 to 0.083), respectively. Magnetic resonance angiography correctly classified 95.3%, overstaged 3.1%, and understaged 1.6% of arterial segments. LIMITATION: Similar to most studies of computed tomographic angiography in PAD, the primary studies reported the diagnostic accuracy of MRA on a per-segment basis, not a per-patient basis. CONCLUSION: This meta-analysis of 32 prospective studies further increases the evidence that contrast-enhanced MRA has high accuracy for identifying or excluding clinically relevant arterial steno-occlusions in adults with PAD symptoms. PRIMARY FUNDING SOURCE: None.


Assuntos
Arteriopatias Oclusivas/diagnóstico , Angiografia por Ressonância Magnética/métodos , Doenças Vasculares Periféricas/diagnóstico , Arteriopatias Oclusivas/etiologia , Meios de Contraste , Humanos , Perna (Membro)/irrigação sanguínea , Doenças Vasculares Periféricas/complicações , Projetos de Pesquisa/normas , Sensibilidade e Especificidade
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa