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1.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469314

RESUMO

Abstract Understanding morphological and physiological changes under different light conditions in native fruit species in juveniles stage is important, as it indicate the appropriate environment to achieve vigorous saplings. We aimed to verify growth and morphophysiological changes under shade gradient in feijoa (Acca sellowiana (O. Berg) Burret) to achieve good quality saplings adequate to improve cultivation in orchards. The saplings were grown for twenty-one-month under four shading treatments (0%, 30%, 50%, and 80%). Growth, photosynthetic pigments, gas exchanges, chlorophyll fluorescence, and leaf anatomy parameters were evaluated. Saplings under full sun and 30% shade had higher height and diameter growth and dry mass accumulation due to higher photosynthesis rate. As main acclimatization mechanisms in feijoa saplings under 80% shade were developed larger leaf area, reduced leaf blade thickness, and enhanced quantum yield of photosystem II. Even so, the net CO2 assimilation and the electron transport rate was lower and, consequently, there was a restriction on the growth and dry mass in saplings under deep shade. Therefore, to obtain higher quality feijoa saplings, we recommend that it be carried out in full sun or up to 30% shade, to maximize the sapling vigor in nurseries and, later, this light environment can also be used in orchards for favor growth and fruit production.


Resumo A verificação de mudanças morfológicas e fisiológicas sob diferentes condições luminosas em espécies frutíferas nativas em estágio juvenil é importante, uma vez que indicam o ambiente adequado para a formação de mudas com alto vigor. Objetivou-se verificar o crescimento e as alterações morfofisiológicas sob gradiente de sombreamento em mudas de feijoa (Acca sellowiana (O. Berg) Burret) para obter mudas de boa qualidade, adequadas para fomentar os plantios da espécie em pomares. As mudas foram cultivadas por vinte e um meses sob quatro tratamentos de sombreamento (0%, 30%, 50% e 80%). Foram avaliados parâmetros de crescimento, pigmentos fotossintéticos, trocas gasosas, fluorescência da clorofila e anatomia foliar. Mudas a pleno sol e 30% de sombra apresentaram maior crescimento em altura, diâmetro e acúmulo de massa seca, devido à maior taxa de fotossíntese. Como principais mecanismos de aclimatação sob 80% de sombra, as mudas desenvolveram maior área foliar, redução da espessura do limbo foliar e aumento do rendimento quântico do fotossistema II. Mesmo assim, a assimilação líquida de CO2 e a taxa de transporte de elétrons foram menores e, consequentemente, houve restrição ao crescimento e acúmulo de massa seca das mudas no maior nível de sombreamento. Portanto, para a obtenção de mudas de feijoa de maior qualidade, recomendamos que seja realizada a pleno sol ou até 30% de sombra, para maximizar o vigor das mudas em viveiros e, posteriormente, este ambiente de luz também pode ser utilizado em pomares para favorecer o crescimento e a produção de frutos.

2.
Braz. j. biol ; 84: e252364, 2024. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355885

RESUMO

Abstract Understanding morphological and physiological changes under different light conditions in native fruit species in juveniles' stage is important, as it indicate the appropriate environment to achieve vigorous saplings. We aimed to verify growth and morphophysiological changes under shade gradient in feijoa (Acca sellowiana (O. Berg) Burret) to achieve good quality saplings adequate to improve cultivation in orchards. The saplings were grown for twenty-one-month under four shading treatments (0%, 30%, 50%, and 80%). Growth, photosynthetic pigments, gas exchanges, chlorophyll fluorescence, and leaf anatomy parameters were evaluated. Saplings under full sun and 30% shade had higher height and diameter growth and dry mass accumulation due to higher photosynthesis rate. As main acclimatization mechanisms in feijoa saplings under 80% shade were developed larger leaf area, reduced leaf blade thickness, and enhanced quantum yield of photosystem II. Even so, the net CO2 assimilation and the electron transport rate was lower and, consequently, there was a restriction on the growth and dry mass in saplings under deep shade. Therefore, to obtain higher quality feijoa saplings, we recommend that it be carried out in full sun or up to 30% shade, to maximize the sapling vigor in nurseries and, later, this light environment can also be used in orchards for favor growth and fruit production.


Resumo A verificação de mudanças morfológicas e fisiológicas sob diferentes condições luminosas em espécies frutíferas nativas em estágio juvenil é importante, uma vez que indicam o ambiente adequado para a formação de mudas com alto vigor. Objetivou-se verificar o crescimento e as alterações morfofisiológicas sob gradiente de sombreamento em mudas de feijoa (Acca sellowiana (O. Berg) Burret) para obter mudas de boa qualidade, adequadas para fomentar os plantios da espécie em pomares. As mudas foram cultivadas por vinte e um meses sob quatro tratamentos de sombreamento (0%, 30%, 50% e 80%). Foram avaliados parâmetros de crescimento, pigmentos fotossintéticos, trocas gasosas, fluorescência da clorofila e anatomia foliar. Mudas a pleno sol e 30% de sombra apresentaram maior crescimento em altura, diâmetro e acúmulo de massa seca, devido à maior taxa de fotossíntese. Como principais mecanismos de aclimatação sob 80% de sombra, as mudas desenvolveram maior área foliar, redução da espessura do limbo foliar e aumento do rendimento quântico do fotossistema II. Mesmo assim, a assimilação líquida de CO2 e a taxa de transporte de elétrons foram menores e, consequentemente, houve restrição ao crescimento e acúmulo de massa seca das mudas no maior nível de sombreamento. Portanto, para a obtenção de mudas de feijoa de maior qualidade, recomendamos que seja realizada a pleno sol ou até 30% de sombra, para maximizar o vigor das mudas em viveiros e, posteriormente, este ambiente de luz também pode ser utilizado em pomares para favorecer o crescimento e a produção de frutos.


Assuntos
Myrtaceae , Feijoa , Fotossíntese , Folhas de Planta , Aclimatação , Luz
3.
Surg Endosc ; 37(4): 3224-3232, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36443563

RESUMO

BACKGROUND: The reperfused human cadaver is a validated simulator for surgery. We aimed to use it as a colonoscopy simulator. METHODS: Novices, intermediates and skilled participants in gastrointestinal endoscopy were included. They performed one colonoscopy on a reperfused human cadaver and reaching rates, time, and length needed to reach anatomical landmarks were reported for construct validity analysis. We also assessed our model realism (SRS survey), educational content (CVS survey) and task load (NASA-TLX index). Score items were collected and defined as "favorable" when items were rated ≥ 5/7 with an inter-quartile range (IQR) overlapping four, and "very favorable" when rated ≥ 5/7 with an IQR excluding four (neutral). Primary endpoints were the rectosigmoid junction (RSJ) reaching rate and the descending colon (DC) reaching time. Secondary objectives were SRS, CVS and NASA-TLX questionnaire results. RESULTS: A total of 11 skilled participants, 5 intermediates and 8 novices were included. Skilled participants reached RSJ more often than novice and intermediary groups, respectively, 100%, 80% and 75% without differing significantly. They reached DC more frequently (100% for skilled, 80% for intermediates and 50% for novices, p = 0.018). The median time to reach RSJ (59, 272 and 686 s for skilled, intermediates and novices group, respectively) and DC (90, 534 and 1360 s for skilled, intermediates and novices) was significantly shorter for skilled participants (both p < .01). Nineteen out of the 22 items composing the realism survey obtained "very favorable" and "favorable" scores. Educational content was designated as "very favorable". Mental, physical, and technical demands were gradually higher the lower the initial level of experience. CONCLUSIONS: Reperfused human cadaver model has the potential to be valid simulation tool for diagnostic colonoscopy training.


Assuntos
Colonoscopia , Treinamento por Simulação , Humanos , Projetos Piloto , Escolaridade , Cadáver , Simulação por Computador , Competência Clínica
4.
Braz J Biol ; 84: e252364, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35019092

RESUMO

Understanding morphological and physiological changes under different light conditions in native fruit species in juveniles' stage is important, as it indicate the appropriate environment to achieve vigorous saplings. We aimed to verify growth and morphophysiological changes under shade gradient in feijoa (Acca sellowiana (O. Berg) Burret) to achieve good quality saplings adequate to improve cultivation in orchards. The saplings were grown for twenty-one-month under four shading treatments (0%, 30%, 50%, and 80%). Growth, photosynthetic pigments, gas exchanges, chlorophyll fluorescence, and leaf anatomy parameters were evaluated. Saplings under full sun and 30% shade had higher height and diameter growth and dry mass accumulation due to higher photosynthesis rate. As main acclimatization mechanisms in feijoa saplings under 80% shade were developed larger leaf area, reduced leaf blade thickness, and enhanced quantum yield of photosystem II. Even so, the net CO2 assimilation and the electron transport rate was lower and, consequently, there was a restriction on the growth and dry mass in saplings under deep shade. Therefore, to obtain higher quality feijoa saplings, we recommend that it be carried out in full sun or up to 30% shade, to maximize the sapling vigor in nurseries and, later, this light environment can also be used in orchards for favor growth and fruit production.


Assuntos
Feijoa , Myrtaceae , Aclimatação , Luz , Fotossíntese , Folhas de Planta
5.
AJNR Am J Neuroradiol ; 42(8): 1380-1386, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34140276

RESUMO

BACKGROUND AND PURPOSE: Collateral blood supply is a key determinant of outcome in large-vessel occlusion acute ischemic stroke. Single- and multiphase CTA collateral scoring systems have been described but are subjective and require training. We aimed to test whether the CTP-derived hypoperfusion intensity ratio is associated with CTA collateral status and whether a threshold hypoperfusion intensity ratio exists that predicts poor CTA collaterals. MATERIALS AND METHODS: Imaging and clinical data of consecutive patients with large-vessel occlusion acute ischemic stroke were retrospectively reviewed. Single-phase CTA and multiphase CTA scoring were performed by 2 blinded neuroradiologists using the Tan, Maas, and Calgary/Menon methods. CTP was processed using RApid processing of PerfusIon and Diffusion software (RAPID). Hypoperfusion intensity ratio = ratio of brain volume with time-to-maximum >10 seconds over time-to-maximum >6-second volume. Correlation between the hypoperfusion intensity ratio and CTA collateral scores was calculated using the Pearson correlation. The optimal threshold of the hypoperfusion intensity ratio for predicting poor collaterals was determined using receiver operating characteristic curve analysis. RESULTS: Fifty-two patients with large-vessel occlusion acute ischemic stroke were included. Multiphase CTA collateral scoring showed better interrater agreement (κ = 0.813) than single-phase CTA (Tan, κ = 0.587; Maas, κ = 0.273). The hypoperfusion intensity ratio correlated with CTA collateral scores (multiphase CTA: r = -0.55; 95% CI, -0.67 to -0.40; P ≤ .001). The optimal threshold for predicting poor multiphase CTA collateral status was a hypoperfusion intensity ratio of >0.45 (sensitivity = 78%; specificity = 76%; area under the curve = 0.86). Patients with high hypoperfusion intensity ratio/poor collateral status had lower ASPECTS/larger infarcts, higher NIHSS scores, and larger hypoperfused volumes. CONCLUSIONS: The hypoperfusion intensity ratio is associated with CTA collateral status in patients with large-vessel occlusion acute ischemic stroke. The hypoperfusion intensity ratio is an automated and quantitative alternative to CTA collateral scoring methods for both clinical and future stroke trial settings.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/diagnóstico por imagem , Angiografia Cerebral , Circulação Colateral , Angiografia por Tomografia Computadorizada , Humanos , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem
6.
Can Assoc Radiol J ; 71(3): 266-280, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32157894

RESUMO

Although acute ischemic stroke remains one of the most common causes of death and disability worldwide, it is a potentially treatable condition if appropriately managed in a timely manner. The goals of acute stroke imaging include establishing a diagnosis as fast as possible with (1) accurate infarct quantification, (2) intracranial and cervical vasculature assessment, and (3) brain perfusion analysis for detection of infarct core and potentially salvageable penumbra allowing optimal patient selection for appropriate therapy. Given the extensive number of images generated from acute stroke imaging studies and as "time is brain," this article aims to highlight a logical approach for the radiologist in acute stroke computed tomography imaging in order to accurately interpret and communicate results in a timely manner.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Angiografia Cerebral/métodos , Angiografia por Tomografia Computadorizada/métodos , Humanos , Interpretação de Imagem Radiográfica Assistida por Computador
7.
AJNR Am J Neuroradiol ; 41(1): 64-70, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31896566

RESUMO

BACKGROUND AND PURPOSE: Brain parenchymal hyperdensity on postthrombectomy CT in patients with acute stroke can be due to hemorrhage and/or contrast staining. We aimed to determine whether iodine concentration within contrast-stained parenchyma compared with an internal reference in the superior sagittal sinus on dual-energy CT could predict subsequent intracerebral hemorrhage. MATERIALS AND METHODS: Seventy-one patients with small infarct cores (ASPECTS ≥ 7) and good endovascular recanalization (modified TICI 2b or 3) for anterior circulation large-vessel occlusion were included. Brain parenchymal iodine concentration as per dual-energy CT and the percentage of contrast staining relative to the superior sagittal sinus were recorded and correlated with the development of intracerebral hemorrhage using Mann-Whitney U and Fisher exact tests. RESULTS: Forty-three of 71 patients had parenchymal hyperdensity on initial dual-energy CT. The median relative iodine concentration compared with the superior sagittal sinus was significantly higher in those with subsequent intracerebral hemorrhage (137.9% versus 109.2%, P = .007). By means of receiver operating characteristic analysis, a cutoff value of 100% (iodine concentration relative to the superior sagittal sinus) enabled identification of patients going on to develop intracerebral hemorrhage with 94.75% sensitivity, 43.4% specificity, and a likelihood ratio of 1.71. CONCLUSIONS: Within our cohort of patients, the relative percentage of iodine concentration at dual-energy CT compared with the superior sagittal sinus was a reliable predictor of intracerebral hemorrhage development and may be a useful imaging biomarker for risk stratification after endovascular treatment.


Assuntos
Hemorragia Cerebral/diagnóstico por imagem , Iodo/análise , Neuroimagem/métodos , Acidente Vascular Cerebral/cirurgia , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/cirurgia , Hemorragia Cerebral/etiologia , Estudos de Coortes , Procedimentos Endovasculares , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Sensibilidade e Especificidade , Acidente Vascular Cerebral/complicações , Seio Sagital Superior/diagnóstico por imagem , Trombectomia
8.
Anaesthesist ; 67(12): 936-949, 2018 12.
Artigo em Alemão | MEDLINE | ID: mdl-30511110

RESUMO

In January 2018 the recent revision of the S2k guidelines on calculated parenteral initial treatment of bacterial diseases in adults-update 2018 (Editor: Paul Ehrlich Society for Chemotherapy, PEG) was realized. It is a helpful tool for the complex infectious disease setting in an intensive care unit. The present summary of the guidelines focuses on the topics of anti-infective agents, including new substances, pharmacokinetics and pharmacodynamics as well as on microbiology, resistance development and recommendations for calculated drug therapy in septic patients. As in past revisions the recent resistance situation and results of new clinical studies are considered and anti-infective agents are summarized in a table.


Assuntos
Antibacterianos/administração & dosagem , Infecções Bacterianas/tratamento farmacológico , Choque Séptico/tratamento farmacológico , Guias como Assunto , Humanos , Infusões Parenterais
9.
Anaesthesist ; 67(6): 461-476, 2018 06.
Artigo em Alemão | MEDLINE | ID: mdl-29766208

RESUMO

Sepsis-induced changes in pharmacokinetic parameters are a well-known problem in intensive care medicine. Dosing of antibiotics in this setting is therefore challenging. Alterations to the substance-specific kinetics of anti-infective substances have an effect on the distribution and excretion processes in the body. Increased clearance and an increased distribution volume (Vd) and particularly compromized organ function with reduced antibiotic elimination are often encountered in patients with sepsis. Renal replacement treatment, which is frequently used in intensive care medicine, represents a substantial intervention in this system. Current international guidelines recommend individualized dosing strategies and adaptation of doses according to measured serum levels and pharmacokinetic/pharmacodynamic (PK/PD) parameters as concepts to optimize anti-infective therapy in the critically ill. Likewise, the recommendation to adjust the administration form of beta-lactam antibiotics to prolonged or continuous infusion can be found increasingly more often in the literature. This article reviews the background of the individual dosing in intensive care patients and their applicability to the clinical routine.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Antibacterianos/farmacocinética , Cuidados Críticos , Monitoramento de Medicamentos , Humanos , Medicina de Precisão , Sepse/tratamento farmacológico , Sepse/metabolismo , Choque Séptico/tratamento farmacológico
10.
AJNR Am J Neuroradiol ; 39(4): 682-686, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29519787

RESUMO

BACKGROUND AND PURPOSE: Idiopathic intracranial hypertension is a syndrome of raised intracranial pressure of unknown etiology. Few MR imaging-based studies have investigated arterial and venous blood flow in these patients. Results are inconclusive, and to our knowledge, no comparison of the hemodynamic parameters before and after CSF pressure reduction has been published. The aim of this study was to assess the short-term effects of normalizing CSF pressure on intracranial flow to better understand the pathophysiology of idiopathic intracranial hypertension. MATERIALS AND METHODS: In this study, we performed quantitative MR imaging-derived flow measurements of brain-supplying arteries and draining veins/dural sinuses to visualize hemodynamic changes in patients with idiopathic intracranial hypertension before and after therapy by lumbar puncture in comparison with a healthy control group. RESULTS: We found differences in patients before and after lumbar puncture in the calculated resistance and pulsatility indices in the superior sagittal sinus. Venous pulsatility showed a negative correlation with CSF pressure in untreated patients. Additionally, there was a trend toward lower flow in the superior sagittal sinus in patients compared with healthy controls. Flow in the internal jugular veins was significantly reduced by lumbar puncture, and the resistance and pulsatility indices differed in patients and controls. The arterial flow was not influenced by pressure normalization. CONCLUSIONS: The results of the present study indicate that venous but not arterial blood flow differs in patients compared with controls and that calculating resistance and pulsatility indices may contribute to assessing short-term hemodynamic changes in patients with diagnosed idiopathic intracranial hypertension before and after CSF diversion.


Assuntos
Hemodinâmica/fisiologia , Angiografia por Ressonância Magnética/métodos , Pseudotumor Cerebral/diagnóstico por imagem , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pseudotumor Cerebral/fisiopatologia , Pseudotumor Cerebral/terapia , Punção Espinal
11.
Med Klin Intensivmed Notfmed ; 113(2): 82-93, 2018 03.
Artigo em Alemão | MEDLINE | ID: mdl-27624768

RESUMO

Pharmacokinetic variability of anti-infective drugs due to pathophysiological changes by severe sepsis and septic shock is a well-known problem for critically ill patients resulting in suboptimal serum and most likely tissue concentrations of these agents.To cover a wide range of potential pathogens, high concentrations of broad spectrum anti-infectives have to reach the site of infection. Microbiological susceptibility testing (susceptible, intermediate, resistant) don't take the pharmacokinetic variability into account and are based on data generated by non-critically ill patients. But inter-patient variability in distribution and elimination of anti-infective drugs in ICU patients is extremely high and also highly unpredictable. Drug clearance of mainly renally eliminated drugs and thus the required dose can differ up to 10-fold due to the variability in renal function in patients with severe infections. To assure a timely and adequate anti-infective regime, individual dosing and therapeutic drug monitoring (TDM) seem to be appropriate tools in the setting of pathophysiological changes in pharmacokinetics (PK) and pharmakodynamics (PD) due to severe sepsis. In the case of known minimal inhibitory concentration, PK/PD indices (time or peak concentration dependent activity) and measured serum level can provide an optimal target concentration for the individual drug and patient.Modern anti-infective management for ICU patients includes more than the choice of drug and prompt application. Individual dosing, optimized prolonged infusion time and TDM give way to new and promising opportunities in infection control.


Assuntos
Antibacterianos , Monitoramento de Medicamentos , Sepse , Choque Séptico , Antibacterianos/uso terapêutico , Humanos , Testes de Sensibilidade Microbiana , Sepse/tratamento farmacológico , Choque Séptico/tratamento farmacológico
12.
J Air Waste Manag Assoc ; 65(5): 523-43, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25947312

RESUMO

UNLABELLED: While most in the scientific community are of the opinion that the composition of fine particulate matter (PM2.5) is an important driver of resultant health effects, there is still some degree of uncertainty regarding those components considered to be most harmful. Reviews of the subject from several perspectives have been published, but to our knowledge a comprehensive review of the epidemiological and toxicological literature related to long-term exposure to PM2.5 components does not exist. We reviewed published epidemiological studies that were of a cohort design, included at least one PM component as well as PM2.5 mass, and included quantitative analysis to relate health outcomes to individual components. Toxicological studies were included if they were ≥5 months in duration and either included at least one PM component as well as PM mass or focused on a specific PM or emissions type. Overall, we find that epidemiological and toxicological evidence for long-term effects of PM components is limited, in contrast to the short-term literature, which is more plentiful. Epidemiological literature suggests that a number of components are associated with health effects, and that no component is unequivocally not so associated. Toxicological studies that can more easily identify potentially causal components are generally limited to long-term studies using concentrated ambient particles (CAPs), of which few long-term studies exist. Epidemiological study designs that utilize existing monitoring data routinely collected by the U.S. Environmental Protection Agency would be valuable additions to the literature, as would novel toxicological studies that incorporate innovative designs to separate components or groups of components, such as denuders, filtration, or other approaches. From a policy perspective, it is important to more comprehensively investigate this issue so that if particular constituents are determined to be more potent in inducing health effects, their sources can be controlled. IMPLICATIONS: Understanding the components of PM2.5 that are most harmful to human health is a critical policy issue. This review examined the epidemiological and toxicological literature related to long-term exposure to PM components and found that, unlike the literature on short-term health effects, there is insufficient information to make clear inferences about causal components. There is a need for further research in this area to exploit existing PM monitoring data in epidemiological studies and to design experimental studies that are able to tease out the effects of multiple constituents.


Assuntos
Poluentes Atmosféricos/toxicidade , Exposição Ambiental , Material Particulado/toxicidade , Humanos , Tamanho da Partícula , Estações do Ano , Fatores de Tempo
13.
J Neurol ; 262(7): 1655-64, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25929656

RESUMO

Camptocormia in Parkinson's disease (PD) is an axial postural disorder usually accompanied by histopathological changes in the paravertebral muscles of unknown etiology. The diagnostic potential of magnetic resonance imaging (MRI) of back muscles in camptocormia has not been systematically assessed. Our objective was to characterize pathological muscle changes with MRI and to develop radiological criteria for camptocormia. The criteria edema, swelling and fatty degeneration in 20 idiopathic PD patients with camptocormia were assessed using MRI (T1w and short tau inversion recovery (STIR) sequences) of the lumbar trunk muscles and compared with 20 group-matched PD patients without camptocormia. Edema and fatty degeneration of the paravertebral muscles were significantly more frequent in camptocormia. Edema correlated negatively and fatty degeneration positively with the duration of camptocormia and not PD. Swelling of the paravertebral muscles, edema and swelling of the quadratus lumborum muscle and rare edema of the psoas muscle were only found in camptocormia patients. In this case-control study the defined MRI criteria distinguish the group of PD patients with camptocormia versus those without. Our findings suggest dynamic changes in the MRI signals over time in the paravertebral muscles: edema and swelling are found initially, followed by fatty atrophic degeneration 2-3 years after the beginning of camptocormia. Muscle MRI qualifies as a tool for categorizing phases of camptocormia as acute or chronic, with potential consequences for therapeutic approaches. The involvement of muscles beyond an isolated impairment of the paravertebral muscles implies a more systemic view with a deregulation of lumbar trunk muscles.


Assuntos
Imageamento por Ressonância Magnética , Músculo Esquelético/patologia , Atrofia Muscular Espinal/patologia , Doença de Parkinson/patologia , Curvaturas da Coluna Vertebral/patologia , Tecido Adiposo/patologia , Idoso , Estudos de Casos e Controles , Edema/etiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Medula Espinal/patologia , Estatística como Assunto
14.
Rofo ; 187(7): 555-60, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25831469

RESUMO

PURPOSE: The efficacy of i. v. thrombolysis in acute stroke with high clot burden is limited. Successful recanalization is very unlikely if the thrombus length exceeds 7 mm. Thus this retrospective controlled study evaluated the efficacy and safety of neurothrombectomy in the treatment of acute embolic stroke in patients selected by a thrombus length of ≥ 8 mm using the stent retriever Trevo(®) device. MATERIALS AND METHODS: 40 patients with acute occlusion of the anterior intracranial arteries with a thrombus length of ≥ 8 mm were treated with neurothrombectomy. We compared the outcome with a historical cohort of 42 patients with a thrombus length of ≥ 8 mm that received i. v. thrombolysis only. Clinical outcome was assessed by modified Rankin scale in both groups at discharge and on day 90. RESULTS: Patients did not differ in age, mRS on admission, thrombus length or time from symptom onset to i. v. thrombolysis, but the thrombectomy group had higher NIHSS on admission. Successful recanalization was achieved in 33/40 patients (83 %) with neurothrombectomy. 15 patients received i. v. thrombolysis prior to neurothrombectomy. Median mRS at discharge was 3.5 (1.25 - 5) vs. 5 (4 - 6; p < 0.01) and on day 90 3 (1 - 4) vs. 5 (4 - 6; p < 0.01). Symptomatic hemorrhage occurred in 3 vs. 7 patients. 3 vs. 17 patients died within 90 days (thrombectomy vs. control each). There were only a few intervention-related complications. CONCLUSION: Thrombectomy in acute stroke with high clot burden using the Trevo(®) device has a low risk and improved clinical outcome compared to i. v. thrombolysis alone. Treatment selection by a clot length of ≥ 8 mm might be a powerful approach to improve the outcome of mechanical thrombectomy. KEY POINTS: • Clot length of ≥ 8 mm might be a valuable criterion for indicating neurothrombectomy. • Thrombolysis only in high clot burden is associated with poor clinical outcome. • Thrombectomy using the Trevo(®) stent retriever is safe and effective.


Assuntos
Fibrinolíticos/administração & dosagem , Embolia Intracraniana/terapia , Trombólise Mecânica/instrumentação , Acidente Vascular Cerebral/terapia , Terapia Trombolítica/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Fibrinolíticos/efeitos adversos , Fibrinolíticos/uso terapêutico , Humanos , Injeções Intravenosas , Trombólise Mecânica/efeitos adversos , Trombólise Mecânica/métodos , Pessoa de Meia-Idade , Hemorragia Pós-Operatória/etiologia , Hemorragia Pós-Operatória/prevenção & controle , Desenho de Prótese , Estudos Retrospectivos , Índice de Gravidade de Doença , Stents , Terapia Trombolítica/efeitos adversos , Resultado do Tratamento , Adulto Jovem
17.
AJNR Am J Neuroradiol ; 32(6): 1021-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21511864

RESUMO

BACKGROUND AND PURPOSE: IH can alter the configuration of anatomic structures of the central nervous system. We determined the sensitivity and specificity of MR imaging to detect these changes in patients with secondary IH. MATERIALS AND METHODS: Patients (n = 36) with IH were prospectively investigated with MR imaging and were matched to 36 controls. MR images were evaluated for elongation and edema of the optic nerves, protrusion of the optic disc, flattening of the posterior sclera, height of the pituitary gland, and width of the optic nerve sheath. On MRV, we recorded venous sinus abnormalities and measured the luminal width of the superior ophthalmic veins. A grading score was introduced to define cranial venous outflow obstruction. RESULTS: Cranial venous outflow obstruction and ONS hydrops were the most valid signs indicating IH with a sensitivity of 94% and 92% and a specificity of 100% and 89%, respectively. Sensitivities and specificities were 56% and 97% for reduced pituitary height, 64% and 78% for flattening of the posterior sclera, 31% and 97% for widening of the superior ophthalmic veins, 33% and 100% for optic disc protrusion, 14% and 100% for optic nerve edema, and 6% and 100% for elongation of the optic nerve. At least 2 MR imaging findings could be demonstrated in each patient but in none of the controls. The number of positive MR imaging findings correlated with CSF pressure (r = 0.62, P = .01). CONCLUSIONS: The combination of cranial and orbital MR imaging and MRV can be highly sensitive and specific in the diagnosis of patients with IH.


Assuntos
Encéfalo/patologia , Hipotensão Intracraniana/diagnóstico , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
18.
Clin Neuroradiol ; 21(1): 5-10, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21109990

RESUMO

PURPOSE: The aim of this study was a comparison of the diagnostic value of time-of-flight magnetic resonance angiography (TOF-MRA) and contrast-enhanced (CE) MRA in the setting of acute stroke MRI. The hypothesis was that CE-MRA has at least the same diagnostic value as the commonly used TOF-MRA. MATERIALS AND METHODS: A total of 66 stroke patients underwent MRI up to 24 h after symptom onset and again after 3­6 days. Primary slices and maximum intensity projections (MIP) of both techniques were evaluated separately and in combination by two readers in consensus. The quality of imaging and degree of vascular pathologies were evaluated. RESULTS: Out of 109 examinations 105 could be evaluated. There were no significant differences in imaging quality in normal vascular segments. For arterial segments distal to an occlusion CE-MRA allowed better visualization of vessels than TOF-MRA. A combined evaluation of both techniques allowed a significantly better assessment than evaluation of images by one technique alone. In contrast to TOF-MRA, CE-MRA included extracranial segments. CONCLUSION: CE-MRA and TOF-MRA do not differ regarding the evaluation of normal intracranial vessels. CE-MRA provides the advantage of good visualization of vessels distal to occluded segments. Furthermore CE-MRA allows visualization of extracranial vessels and faster image acquisition. TOF-MRA can be equivalently used if the administration of contrast agents is not possible.


Assuntos
Algoritmos , Artérias Cerebrais/patologia , Gadolínio , Aumento da Imagem/métodos , Angiografia por Ressonância Magnética/métodos , Acidente Vascular Cerebral/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
AJNR Am J Neuroradiol ; 31(9): 1752-7, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20522569

RESUMO

BACKGROUND AND PURPOSE: Craniospinal hyper- or hypotension leads to morphologic changes in certain intracranial structures. We tested the hypothesis that the amount of CSF in the ONS visible in MR imaging is reduced in patients with CSH. MATERIALS AND METHODS: Nineteen patients with CSH were prospectively studied. Three readers assessed the width of the peri-optical CSF rim at 4 different anatomic positions by using coronal STIR sequences from a 3T MR imaging scanner. The height of the pituitary gland was also measured. Results were compared with normal values obtained with the same imaging technique. Qualitative signs of CSH also recorded were engorgement of venous sinuses, dural enhancement, subdural effusion, narrow ventricles, and sagging brain. RESULTS: CSF signal intensity surrounding the optic nerves was diminished in at least 2 of the 4 positions used for measurements so that decreased diameters of the ONSs were observed in all patients (sensitivity, 100%; specificity, 97%). The height of the pituitary gland was above normal limits in 12 of 19 patients (sensitivity, 63%; specificity, 97%). Frequencies of qualitative signs of CSH varied from 32% to 81%. CONCLUSIONS: The ISSON in patients with CSH is partially or fully collapsed due to reduced CSF content. In comparison with other anatomic markers, this sign showed the highest sensitivity for the diagnosis of patients with CSH in this study.


Assuntos
Hipotensão Intracraniana/patologia , Imageamento por Ressonância Magnética/métodos , Nervo Óptico/patologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Hipotensão Intracraniana/complicações , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
20.
Oncology ; 79(3-4): 247-54, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21372599

RESUMO

OBJECTIVES: This multicenter, retrospective survey evaluated the efficacy and safety of bortezomib retreatment in patients with relapsed multiple myeloma who had responded to initial bortezomib treatment. METHODS: Clinical records of 94 patients receiving bortezomib retreatment in Germany and Switzerland were reviewed. RESULTS: Sixty patients were included according to prespecified criteria. Patients had received a mean 3.7 ± 2.3 therapies prior to initial bortezomib. Overall response rate to bortezomib retreatment was 63.3%; 8 (13.3%), 3 (5.0%) and 27 (45.0%) patients achieved complete response (CR), near-CR and partial response, respectively. Response to retreatment was associated with response to initial treatment (75.0% of patients with CR to initial treatment responded to retreatment) and treatment-free interval (TFI) after initial treatment (76.9 vs. 38.1% overall response rate for patients with TFI >6 vs. ≤ 6 months). After retreatment, median time to progression was 9.3 months. Median TFI was 5.7 months; 31.7, 25.0 and 15.0% of patients experienced a TFI longer than 6, 9 and 12 months, respectively. Reported adverse drug reactions were consistent with the known safety profile of bortezomib and most resolved completely. CONCLUSIONS: These results demonstrate that relapsed multiple myeloma patients who respond to initial bortezomib treatment have a sustained susceptibility to bortezomib and do not experience uncommon toxicity to retreatment.


Assuntos
Antineoplásicos/uso terapêutico , Ácidos Borônicos/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Pirazinas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Bortezomib , Progressão da Doença , Feminino , Alemanha , Humanos , Agências Internacionais , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Retratamento , Estudos Retrospectivos , Taxa de Sobrevida , Suíça , Resultado do Tratamento
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