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Hermite-Gaussian (HG) laser modes are a complete set of solutions to the free-space paraxial wave equation in Cartesian coordinates and represent a close approximation to physically realizable laser cavity modes. Additionally, HG modes can be mode-multiplexed to significantly increase the information capacity of optical communication systems due to their orthogonality. Because cavity tuning and optical communication applications benefit from a machine vision determination of HG modes, convolution neural networks were implemented to detect the lowest 21 unique HG modes with an accuracy greater than 99%. As the effectiveness of a CNN is dependent on the diversity of its training data, extensive simulated and experimental data sets were created for training, validation, and testing.
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AIM: To assess whether changes in body composition could be assessed serially using conventional thoracic computed tomography (CT) and positron-emission tomography (PET)/CT imaging in patients receiving induction chemotherapy for non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: CT-based skeletal muscle volume and density were measured retrospectively from thoracic and lumbar segment CT images from 88 patients with newly diagnosed and untreated NSCLC before and after induction chemotherapy. Skeletal muscle 2-[18F]-fluoro-2-deoxy-d-glucose (FDG) uptake was measured from PET/CT images from a subset of patients (n=42). Comparisons of each metric before and after induction chemotherapy were conducted using the non-parametric Wilcoxon signed-rank test for paired data. The association between clinical factors and percentage change in muscle volume was examined using univariate linear regression models, with adjustment for baseline muscle volume. RESULTS: Following induction chemotherapy, thoracic (-3.3%, p=0.0005) and lumbar (-2.6%, p=0.0101) skeletal muscle volume were reduced (adiposity remained unchanged). The proportion of skeletal muscle with a density <0 HU increased (7.9%, p<0.0001), reflecting a decrease in skeletal muscle density and skeletal muscle FDG uptake increased (10.4-31%, p<0.05). No imaging biomarkers were correlated with overall survival. CONCLUSION: Changes in body composition can be measured from routine thoracic imaging. During chemotherapy skeletal muscle volume and metabolism are altered; however, there was no impact on survival in this retrospective series, and further validation in prospective, well-controlled studies are required.
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Carcinoma Pulmonar de Células não Pequenas/terapia , Fluordesoxiglucose F18/farmacocinética , Neoplasias Pulmonares/terapia , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos/farmacocinética , Tomografia Computadorizada por Raios X , Idoso , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Estadiamento de Neoplasias , Taxa de Sobrevida , Redução de PesoRESUMO
BACKGROUND: Few studies have investigated the effects of exercise on modulation of host factors in cancer patients. We investigated the efficacy of chronic aerobic training on multiple host-related effector pathways in patients with solid tumours. PATIENTS AND METHODS: Paired peripheral blood samples were obtained from 44 patients with solid tumours receiving cytotoxic therapy and synthetic erythropoietin (usual care; n=21) or usual care plus supervised aerobic training (n=23) for 12 weeks. Samples were characterised for changes in immune, cytokine and angiogenic factors, and metabolic intermediates. Aerobic training consisted of three supervised cycle ergometry sessions per week at 60% to 100% of peak oxygen consumption (VO2peak), 30-45 min per session, for 12 weeks following a nonlinear prescription. RESULTS: The between-group delta change in cardiopulmonary function was +4.1 ml kg (-1) min(-1), favouring aerobic training (P<0.05). Significant pre-post between-group differences for five cytokine and angiogenic factors (HGF, IL-4, macrophage inflammatory protein-1ß (MIP-1ß), vascular endothelial growth factor (VEGF), and TNF-α) also favour the aerobic training group (P's<0.05). These reductions occurred in conjunction with nonsignificant group differences for T lymphocytes CD4(+), CD8(+), and CD8(+)/CD45RA (P<0.10). For these factors, circulating concentrations generally increased from baseline to week 12 in the aerobic training group compared with decreases or no change in the usual care group. No significant changes in any metabolic intermediates were observed. CONCLUSIONS: Aerobic training alters host availability of select immune-inflammatory effectors in patients with solid tumours; larger confirmatory studies in more homogenous samples are warranted.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/sangue , Eritropoetina/administração & dosagem , Terapia por Exercício/métodos , Neoplasias/terapia , Fenômenos Fisiológicos Cardiovasculares , Ensaios Clínicos como Assunto , Terapia Combinada , Eritropoetina/uso terapêutico , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Consumo de Oxigênio , Projetos PilotoRESUMO
BACKGROUND: Bleomycin-etoposid-cisplatin (BEP) chemotherapy is curative in most patients with disseminated germ cell cancer (GCC) but also associated with toxic actions and dysfunction in non-targeted tissues. We investigated changes in muscle function during BEP and the safety and efficacy of resistance training to modulate these changes. METHODS: Thirty GCC patients were randomly assigned to resistance training (resistance training group (INT), n=15) or usual care (CON, n=15) during 9 weeks of BEP therapy. Resistance training consisted of thrice weekly sessions of four exercises, 3-4 sets/exercise of 10-15 repetitions at 12-15 repetition maximum load. The primary endpoint was muscle fibre size, assessed in muscle biopsies from musculus vastus lateralis. Secondary endpoints were fibre phenotype composition, body composition, strength, blood biochemistry and patient-reported endpoints. Healthy age-matched subjects (REF, n=19) performed the same RT-programme for comparison purposes. RESULTS: Muscle fibre size decreased by -322 µm(2) (95% confidence interval (CI): -899 to 255; P=0.473) in the CON-group and increased by +206 µm(2) (95% CI: -384 to 796; P=0.257) in the INT-group (adjusted mean difference (AMD), +625 µm(2), 95% CI: -253 to 1503, P=0.149). Mean differences in type II fibre size (AMD, +823 µm(2), P=0.09) and lean mass (AMD, +1.49 kg, P=0.07) in favour of the INT-group approached significance. The REF-group improved all muscular endpoints and had significantly superior changes compared with the INT-group (P<0.05). CONCLUSIONS: BEP was associated with significant reduction in lean mass and strength and trends toward unfavourable changes in muscle fibre size and phenotype composition. Resistance training was safe and attenuated dysfunction in selected endpoints, but BEP blunted several positive adaptations observed in healthy controls. Thus, our study does not support the general application of resistance training in this setting but larger-scaled trials are required to confirm this finding.
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Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Músculo Esquelético/efeitos dos fármacos , Neoplasias Embrionárias de Células Germinativas/terapia , Treinamento Resistido/efeitos adversos , Treinamento Resistido/métodos , Neoplasias Testiculares/terapia , Adulto , Bleomicina/administração & dosagem , Bleomicina/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Terapia Combinada , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Humanos , Masculino , Músculo Esquelético/fisiopatologia , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Neoplasias Embrionárias de Células Germinativas/fisiopatologia , Estudos Prospectivos , Método Simples-Cego , Neoplasias Testiculares/tratamento farmacológico , Neoplasias Testiculares/fisiopatologiaRESUMO
BACKGROUND: Muscle dysfunction is a prevalent phenomenon in the oncology setting where patients across a wide range of diagnoses are subject to impaired muscle function regardless of tumor stage and nutritional state. Here, we review the current evidence describing the degree, causes and clinical implications of muscle dysfunction in cancer patients. The efficacy of exercise training to prevent and/or mitigate cancer-related muscle dysfunction is also discussed. DESIGN: We identified 194 studies examining muscular outcomes in cancer patients by searching PubMed and EMBASE databases. RESULTS: Muscle dysfunction is evident across all stages of the cancer trajectory. The causes of cancer-related muscle dysfunction are complex, but may involve a wide range of tumor-, therapy- and/or lifestyle-related factors, depending on the clinical setting of the individual patient. The main importance of muscle dysfunction in cancer patients lies in the correlation to vital clinical end points such as cancer-specific and all-cause mortality, therapy complications and quality of life (QoL). Such associations strongly emphasize the need for effective therapeutic countermeasures to be developed and implemented in oncology practice. Significant progress has been made over the last decade in the field of exercise oncology, indicating that exercise training constitutes a potent modulator of skeletal muscle function in patients with cancer. CONCLUSION: There are clear associations between muscle dysfunction and critical clinical end points. Yet there is a discrepancy between timing of exercise intervention trials, which can improve muscle function, and study populations in whom muscle function are proven prognostic important for clinical end points. Thus, future exercise trials should in early-stage patients, be powered to evaluate clinical outcomes associated with improvements in muscle function, or be promoted in advanced stage settings, aiming to reverse cancer-related muscle dysfunction, and thus potentially improve time-to-progression, treatment toxicity and survival.
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Músculo Esquelético/fisiopatologia , Neoplasias/fisiopatologia , Animais , Terapia por Exercício , Humanos , Força Muscular , Músculo Esquelético/patologia , Neoplasias/mortalidade , Neoplasias/terapia , Qualidade de Vida , Resultado do TratamentoRESUMO
BACKGROUND: Sedentary behavior and impaired cardiovascular reserve capacity are common late effects of cancer therapy emphasizing the need for effective strategies to increase physical activity (PA) in cancer survivors. We examined the efficacy of a 12-month exercise-based rehabilitation program on self-reported PA, cardiorespiratory fitness (VO2peak), strength, and patient-reported outcomes. PATIENTS AND METHODS: Two hundred fourteen post-treatment cancer survivors were randomly assigned to a 12-month rehabilitation program consisting of individual (x3) and group-based (x6) counseling in combination with once weekly high-intensity group-based exercise training (the Copenhagen Physical Activity after Cancer Treatment, PACT; n = 108) or to a health evaluation program (HE, n = 106). Study outcomes were assessed at baseline, 6 months, and 12 months. RESULTS: After 12 months, the percentage of patients reporting meeting PA goal behavior (≥3 h/week) was significantly increased in the PACT group versus the HE group (70.4% versus 43.4%, P = 0.001). Repeated measures analyses indicated a statistically significant improvement in VO2peak (l min(-1)) in favour of PACT (treatment effect ratio = 1.04; 95% confidence interval 1.00-1.07; P = 0.032). Significant between group differences were also observed for strength (P < 0.001), depression (P = 0.020) and mental health (P = 0.040). CONCLUSION: A 12-month exercise-based rehabilitation program is an effective strategy to promote PA and improve VO2peak in cancer survivors.
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Exercício Físico , Nível de Saúde , Neoplasias/reabilitação , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora , Aptidão Física , Qualidade de Vida , Reabilitação/métodos , Sobreviventes , Resultado do TratamentoRESUMO
The use of liquid hydrogen as a long-term replacement for hydrocarbon fuel for land and air transportation seems technically feasible. It is an ideal fuel from the standpoint of a completely cyclic system, serving as a "working substance" in a closed chemical and thermodynamic cycle. The energy-per-unit-weight advantage (a factor of 3) over gasoline or any other hydrocarbon fuel makes liquid hydrogen particularly advantageous for air craft and long-range land transport. As a pollution-free fuel, it must be seriously considered as the logical replacement for hydrocarbons in the 21st century.
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BACKGROUND: Obesity, a cause of subclinical inflammation, is associated with increased risk of high-grade prostate cancer (PC) and poor outcomes. Whether inflammation occurs in periprostatic white adipose tissue (WAT), and contributes to the negative impact of obesity on PC aggressiveness, is unknown. METHODS: In a single-center, cross-sectional design, men with newly diagnosed PC undergoing radical prostatectomy were eligible for study participation. The primary objective was to examine the prevalence of periprostatic WAT inflammation defined by the presence of crown-like structures (CLS-P) as detected by CD68 immunohistochemistry. Secondary objectives were to explore the clinical and systemic correlates of periprostatic WAT inflammation. Tumor characteristics and host factors including BMI, adipocyte diameter, and circulating levels of lipids, adipokines, and other metabolic factors were measured. Wilcoxon rank-sum, Chi-square, or Fisher's exact tests, and generalized linear regression were used to examine the association between WAT inflammation and tumor and host characteristics. RESULTS: Periprostatic fat was collected from 169 men (median age 62 years; median BMI 28.3). Periprostatic WAT inflammation was identified in 49.7% of patients and associated with higher BMI (P=0.02), larger adipocyte size (P=0.004) and Gleason grade groups IV/V tumors (P=0.02). The relationship between WAT inflammation and high Gleason grade remained significant after adjusting for BMI (P=0.04). WAT inflammation correlated with higher circulating levels of insulin, triglycerides, and leptin/adiponectin ratio, and lower high density lipoprotein cholesterol, compared to those without WAT inflammation (P's <0.05). CONCLUSION: Periprostatic WAT inflammation is common in this cohort of men with PC and is associated with high-grade PC.
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Tecido Adiposo Branco/patologia , Inflamação/patologia , Obesidade/patologia , Neoplasias da Próstata/patologia , Tecido Adiposo Branco/metabolismo , Idoso , Índice de Massa Corporal , Humanos , Inflamação/complicações , Inflamação/metabolismo , Inflamação/cirurgia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Obesidade/complicações , Obesidade/metabolismo , Obesidade/cirurgia , Próstata/metabolismo , Próstata/patologia , Próstata/cirurgia , Prostatectomia , Neoplasias da Próstata/complicações , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/cirurgiaRESUMO
Epithelial cell cultures of the normal human prostate gland were established. The subculturing of these cultures was accomplished with a novel nonenzymatic technique. These cultures were defined as normal epithelial cells on the basis of ultrastructure, karyotype, and inability to grow in soft agar.
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Próstata/citologia , Adesão Celular/efeitos dos fármacos , Divisão Celular , Linhagem Celular , Cromossomos Humanos , Meios de Cultura , Células Epiteliais , Humanos , Masculino , Métodos , Potássio/farmacologia , Próstata/ultraestruturaRESUMO
Rhodamine-123, a lipophilic, cationic, rhodocyanine dye, has been reported to have carcinoma selective toxicity in vitro and in vivo. This phase I clinical trial established the safety and pharmacokinetics of Rhodamine-123 administered to men with hormone refractory prostate cancer. A single dose toxicity study of Rhodamine-123 determined the maximum tolerated dose. A multiple dose toxicity study assessed the safety of Rhodamine-123 at the maximum tolerated dose level. Transient and variable toxicities noted following Rhodamine-123 infusion resolved within 6 hours following infusion. Pharmacokinetic analyses of sera showed no accumulation of drug with repeated monthly administrations. Drug retention was confirmed in prostatic tissue following Rhodamine-123 administration. PSA doubling times lengthened variably suggesting drug efficacy but the data were not statistically significant. The maximum tolerated dose of Rhodamine-123 is 96 mg/m2. The drug can be safely administered at monthly intervals without detectable drug accumulation in serum. Rhodamine-123 is retained by prostatic tumor tissue.
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Neoplasias Hormônio-Dependentes/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Rodamina 123/farmacocinética , Rodamina 123/uso terapêutico , Idoso , Relação Dose-Resposta a Droga , Esquema de Medicação , Seguimentos , Humanos , Infusões Intravenosas , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Hormônio-Dependentes/mortalidade , Neoplasias Hormônio-Dependentes/patologia , Seleção de Pacientes , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Rodamina 123/efeitos adversos , Medição de Risco , Análise de Sobrevida , Resultado do TratamentoRESUMO
Experiments were designed to test the hypothesis that renal medulla is more sensitive to hypoxia than is the cortex. Using the one-dimensional phase encoding technique to perform 31phosphorus magnetic resonance spectroscopy in a perfused porcine kidney preparation, cortex and medulla were differentiated on the basis of the unique resonance at 3 ppm found only in medulla. Hypotension-induced hypoxia reduced total renal oxygen consumption by 60%, and urine flow by 44%. Nonlocalized 31P MRS spectra showed that [ATP]/[Pi] ratio fell by 40%, and intrarenal pH by 0.1 unit. Virtually all of these changes could be accounted for by changes in the renal cortex, where initial [ATP]/[Pi] was higher than in medulla (1.16 vs. 0.68). In medulla [ATP]/[Pi] fell only 29% (n.s. versus control) and pH remained unchanged during hypotension. Thus the cortex appears to be more sensitive to hypoxia in this preparation, and observations fail to support the proposed hypothesis. They are consistent, however, with the greater capacity of medulla for anaerobic glycolysis. Localized 31P MRS provides improved noninvasive metabolic assessment of cold-preserved kidneys.
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Hipotensão/fisiopatologia , Córtex Renal/fisiopatologia , Medula Renal/fisiopatologia , Trifosfato de Adenosina/metabolismo , Animais , Diurese , Concentração de Íons de Hidrogênio , Hipóxia/fisiopatologia , Espectroscopia de Ressonância Magnética , Consumo de Oxigênio , Perfusão , Fosfatos/metabolismo , SuínosRESUMO
Thirteen patients were examined for grade, stage, and extent of their prostatic cancer, utilizing nuclear magnetic resonance imaging (MRI) and clinical workup for metastases. Of these 13 patients, 12 had known prostatic cancer proved by needle biopsy or by pathologic examination of transurethral prostatectomy tissue. Five of these patients underwent radical surgery allowing further correlation of clinical findings and MRI data with the surgical pathologic findings. MRI of the prostate was found to be a sensitive modality in detecting prostatic carcinoma and showing extension of disease in some cases. Also, in some cases it was not always possible to differentiate between prostatic carcinoma and benign prostatic hyperplasia with MRI.
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Carcinoma/patologia , Imageamento por Ressonância Magnética , Neoplasias da Próstata/patologia , Idoso , Carcinoma/diagnóstico , Humanos , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias da Próstata/diagnósticoRESUMO
The in vitro uptake and release behaviour of cromolyn sodium, ketotifen fumarate, ketorolac tromethamine and dexamethasone sodium phosphate with silicon-containing (lotrafilcon and balafilcon) and p-HEMA-containing (etafilcon, alphafilcon, polymacon, vifilcon and omafilcon) hydrogel contact lenses indicated that both drug and material affected the uptake and release behaviour. Rapid uptake and release (within 50 min) was observed for all drugs except ketotifen fumarate which was more gradual taking approximately 5h. Furthermore, the maximum uptake differed significantly between drugs and materials. The highest average uptake (7879+/-684 microg/lens) was cromolyn sodium and the lowest average uptake (67+/-13 microg/lens) was dexamethasone sodium phosphate. Partial release of the drug taken up was observed for all drugs except dexamethasone sodium phosphate where no release was detected. Sustained release was demonstrated only by ketotifen fumarate. Drug uptake/release appeared to be a function of lens material ionicity, water and silicon content. The silicon-containing materials released less drug than the p-HEMA-containing materials. The lotrafilcon material demonstrated less interactions with the drugs than the balafilcon material which can be explained by their different bulk composition and surface treatment.
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Lentes de Contato Hidrofílicas , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Metacrilatos/química , Silício/química , Adsorção , SolubilidadeRESUMO
Contact lenses can induce changes in the epithelium, stroma and endothelium of the cornea, all of which can be observed clinically using the slit-lamp biomicroscope. These complications include epithelial microcysts, vacuoles and staining, stromal oedema and vascularization, and endothelial polymegethism and blebs. Each complication can be attributed to one or more aetiological factors such as hypoxia, hypercapnia, tissue acidosis, trauma, hypersensitivity and toxicity. This review outlines the way in which these complications manifest clinically, and consideration is given to management strategies and likely prognoses. Early detection of these conditions and appropriate action can usually prevent more serious ocular complications.
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A comprehensive review of the recent literature reveals that exercise has a positive effect on a broad range of quality-of-life parameters after patients are diagnosed as having cancer. The general exercise prescription is moderate-intensity exercise, 3 to 5 days per week, 20 to 30 minutes per session. Conditions that warrant prescription modification include fatigue periods during treatment, acute or chronic physical impairments that may have resulted from surgery or adjuvant therapy, and the presence of bone cancer. Research suggests that physicians who prescribe exercise improve motivation and adherence in their patients who have cancer.
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Portal verification has led many radiation therapy departments to implement policies of taking weekly port films for every patient. This has caused some to question the impact of port film dosage, once considered negligible. Using clinical data from 100 patients, this article examines the impact of port film dosage and offers suggestions for documentation and alternatives for decreasing dosages.
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Radioterapia/métodos , Tecnologia Radiológica , Humanos , Garantia da Qualidade dos Cuidados de Saúde , Radioterapia/normasRESUMO
The feasibility of symptom-limited cardiopulmonary exercise testing (CPET) prior to allo-SCT was assessed in addition to the prognostic value of CPET-derived measures. CPET was performed prospectively on 21 patients with hematologic malignancies, with assessments of peak (for example, peak oxygen consumption, VO2peak) and submaximal (for example, ventilatory threshold (VT)) measures of cardiopulmonary function. No serious adverse events were observed during CPET procedures, with 95% of patients achieving criteria for a peak test. Mean VO2peak was 24.7±6.4 mL kg(-1 )min(-1) (range: 10.9-35.5), equivalent to 29%±17% below that of age-matched healthy controls. All patients proceeded with the conditioning regimen followed by allo-SCT. Median follow-up was 25 months. During this period, 11 (52.4%) patients died (n=6, relapsed disease; n=5, non-relapse mortality (NRM)); 9 patients (43%) developed pulmonary toxicity. In univariate analyses, both peak and submaximal markers of cardiopulmonary function were predictors of OS, pulmonary toxicity and NRM. For OS, the HR for VO2peak and VT were 0.89 (95% CI, 0.8-0.99, P=0.04) and 0.84 (95% CI, 0.71-0.98, P=0.03), respectively. In conclusion, CPET is safe and feasible prior to allo-SCT. Patients have marked impairments in cardiopulmonary function prior to allo-SCT. CPET-derived metrics may complement conventional measures to improve risk stratification.
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Teste de Esforço/métodos , Transplante de Células-Tronco Hematopoéticas/métodos , Condicionamento Pré-Transplante/métodos , Adulto , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Adulto JovemRESUMO
There is considerable utility in the use of transcranial Doppler ultrasound (TCD) to assess cerebrovascular function. The brain is unique in its high energy and oxygen demand but limited capacity for energy storage that necessitates an effective means of regional blood delivery. The relative low cost, ease-of-use, non-invasiveness, and excellent temporal resolution of TCD make it an ideal tool for the examination of cerebrovascular function in both research and clinical settings. TCD is an efficient tool to access blood velocities within the cerebral vessels, cerebral autoregulation, cerebrovascular reactivity to CO(2), and neurovascular coupling, in both physiological states and in pathological conditions such as stroke and head trauma. In this review, we provide: (1) an overview of TCD methodology with respect to other techniques; (2) a methodological synopsis of the cerebrovascular exam using TCD; (3) an overview of the physiological mechanisms involved in regulation of the cerebral blood flow; (4) the utility of TCD for assessment of cerebrovascular pathology; and (5) recommendations for the assessment of four critical and complimentary aspects of cerebrovascular function: intra-cranial blood flow velocity, cerebral autoregulation, cerebral reactivity, and neurovascular coupling. The integration of these regulatory mechanisms from an integrated systems perspective is discussed, and future research directions are explored.