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1.
Cell Rep Med ; 5(1): 101363, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38232698

RESUMO

Early time-restricted eating (eTRE) improves aspects of cardiometabolic health. Although the circadian system appears to regulate nutrient absorption, little is known about the effects of eTRE on intestinal absorption. In this randomized crossover trial, 16 healthy adults follow a controlled, weight maintenance diet for 9 days, consuming all calories between 0800 and 1400 (eTRE schedule) or 0800 and 2000 (control schedule). We measure the energy content of the diet, stool, and urine with bomb calorimetry and calculate intestinal energy absorption. The eTRE schedule is more effective than the control eating schedule for improving markers of cardiometabolic health, including 24-h mean glucose concentrations and glycemic variability, assessed as the mean amplitude of glycemic excursions. However, eTRE has no effect on intestinal energy and macronutrient absorption, gastrointestinal transit time, colonic hydrogen gas production, or stool microbial composition, suggesting eTRE does not impact gastrointestinal function. This trial is registered (ClinicalTrials.gov: NCT04877262).


Assuntos
Doenças Cardiovasculares , Dieta , Adulto , Humanos , Ingestão de Energia , Absorção Intestinal , Nutrientes
2.
Magn Reson Med ; 91(5): 1803-1821, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38115695

RESUMO

PURPOSE: K trans $$ {K}^{\mathrm{trans}} $$ has often been proposed as a quantitative imaging biomarker for diagnosis, prognosis, and treatment response assessment for various tumors. None of the many software tools for K trans $$ {K}^{\mathrm{trans}} $$ quantification are standardized. The ISMRM Open Science Initiative for Perfusion Imaging-Dynamic Contrast-Enhanced (OSIPI-DCE) challenge was designed to benchmark methods to better help the efforts to standardize K trans $$ {K}^{\mathrm{trans}} $$ measurement. METHODS: A framework was created to evaluate K trans $$ {K}^{\mathrm{trans}} $$ values produced by DCE-MRI analysis pipelines to enable benchmarking. The perfusion MRI community was invited to apply their pipelines for K trans $$ {K}^{\mathrm{trans}} $$ quantification in glioblastoma from clinical and synthetic patients. Submissions were required to include the entrants' K trans $$ {K}^{\mathrm{trans}} $$ values, the applied software, and a standard operating procedure. These were evaluated using the proposed OSIP I gold $$ \mathrm{OSIP}{\mathrm{I}}_{\mathrm{gold}} $$ score defined with accuracy, repeatability, and reproducibility components. RESULTS: Across the 10 received submissions, the OSIP I gold $$ \mathrm{OSIP}{\mathrm{I}}_{\mathrm{gold}} $$ score ranged from 28% to 78% with a 59% median. The accuracy, repeatability, and reproducibility scores ranged from 0.54 to 0.92, 0.64 to 0.86, and 0.65 to 1.00, respectively (0-1 = lowest-highest). Manual arterial input function selection markedly affected the reproducibility and showed greater variability in K trans $$ {K}^{\mathrm{trans}} $$ analysis than automated methods. Furthermore, provision of a detailed standard operating procedure was critical for higher reproducibility. CONCLUSIONS: This study reports results from the OSIPI-DCE challenge and highlights the high inter-software variability within K trans $$ {K}^{\mathrm{trans}} $$ estimation, providing a framework for ongoing benchmarking against the scores presented. Through this challenge, the participating teams were ranked based on the performance of their software tools in the particular setting of this challenge. In a real-world clinical setting, many of these tools may perform differently with different benchmarking methodology.


Assuntos
Meios de Contraste , Imageamento por Ressonância Magnética , Humanos , Reprodutibilidade dos Testes , Imageamento por Ressonância Magnética/métodos , Software , Algoritmos
3.
Radiother Oncol ; 183: 109592, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36870608

RESUMO

BACKGROUND AND PURPOSE: Tumour hypoxia is prognostic in head and neck cancer (HNC), associated with poor loco-regional control, poor survival and treatment resistance. The advent of hybrid MRI - radiotherapy linear accelerator or 'MR Linac' systems - could permit imaging for treatment adaptation based on hypoxic status. We sought to develop oxygen-enhanced MRI (OE-MRI) in HNC and translate the technique onto an MR Linac system. MATERIALS AND METHODS: MRI sequences were developed in phantoms and 15 healthy participants. Next, 14 HNC patients (with 21 primary or local nodal tumours) were evaluated. Baseline tissue longitudinal relaxation time (T1) was measured alongside the change in 1/T1 (termed ΔR1) between air and oxygen gas breathing phases. We compared results from 1.5 T diagnostic MR and MR Linac systems. RESULTS: Baseline T1 had excellent repeatability in phantoms, healthy participants and patients on both systems. Cohort nasal concha oxygen-induced ΔR1 significantly increased (p < 0.0001) in healthy participants demonstrating OE-MRI feasibility. ΔR1 repeatability coefficients (RC) were 0.023-0.040 s-1 across both MR systems. The tumour ΔR1 RC was 0.013 s-1 and the within-subject coefficient of variation (wCV) was 25% on the diagnostic MR. Tumour ΔR1 RC was 0.020 s-1 and wCV was 33% on the MR Linac. ΔR1 magnitude and time-course trends were similar on both systems. CONCLUSION: We demonstrate first-in-human translation of volumetric, dynamic OE-MRI onto an MR Linac system, yielding repeatable hypoxia biomarkers. Data were equivalent on the diagnostic MR and MR Linac systems. OE-MRI has potential to guide future clinical trials of biology guided adaptive radiotherapy.


Assuntos
Neoplasias de Cabeça e Pescoço , Oxigênio , Humanos , Imageamento por Ressonância Magnética/métodos , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Hipóxia , Prognóstico , Aceleradores de Partículas
4.
J Nutr ; 153(3): 749-759, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36805182

RESUMO

BACKGROUND: The lack of complete amino acid composition data in food composition databases has made determining population-wide amino acid intake difficult. OBJECTIVES: This cross-sectional study characterizes habitual intakes of each amino acid and adherence to dietary requirements for each essential amino acid (EAA) in the US population. METHODS: Food and Nutrient Database for Dietary Studies ingredient codes with missing amino acid composition data were matched to similar ingredients with available data so that amino acid composition could be determined for 100% of foods reported in the dietary intake assessment component of NHANES. Amino acid intakes during NHANES 2001-2018 (n = 72,831; ≥2 y) were calculated as relative (mg·kg of ideal body weight-1·d-1) intakes. Data from NHANES 2011-2018 were used to determine the percentage of population consuming less than that recommended by the DRIs for each EAA by age, sex, and race/ethnicity. RESULTS: Relative intakes of EAAs and NEAAs were greatest in those 2-3 y and lowest in older individuals (≥71 y or ≥80 y). In females aged 2-18 y, relative intakes of EAAs were lowest in non-Hispanic White (NHW; histidine, lysine, threonine, methionine, and cysteine) and non-Hispanic Black (NHB; valine, isoleucine, leucine, phenylalanine, tryptophan, and tyrosine) populations and highest in the Asian population. In females aged ≥19 y, relative intakes were lowest in NHW (lysine and methionine only) and NHB populations and highest in the Asian population. In males aged 2-18 y, relative intakes of EAAs were lowest in the NHB population and highest in the Asian population. In males ≥19 y, relative intakes were lowest in NHB and NHW (lysine only) populations and highest in the Hispanic population. Less than 1% of individuals aged ≥19 y did not meet the Estimated Average Requirements for each EAA. CONCLUSIONS: EAA intakes in the US population exceed recommended minimum population requirements. Future studies can use the method described here to quantify amino acid intake and examine relationships with health and disease.


Assuntos
Dieta , Lisina , Masculino , Feminino , Humanos , Estados Unidos , Idoso , Recomendações Nutricionais , Inquéritos Nutricionais , Estudos Transversais , Aminoácidos , Aminoácidos Essenciais , Metionina
5.
Cancers (Basel) ; 14(9)2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35565288

RESUMO

Imaging biomarkers are used in therapy development to identify and quantify therapeutic response. In oncology, use of MRI, PET and other imaging methods can be complicated by spatially complex and heterogeneous tumor micro-environments, non-Gaussian data and small sample sizes. Linear Poisson Modelling (LPM) enables analysis of complex data that is quantitative and can operate in small data domains. We performed experiments in 5 mouse models to evaluate the ability of LPM to identify responding tumor habitats across a range of radiation and targeted drug therapies. We tested if LPM could identify differential biological response rates. We calculated the theoretical sample size constraints for applying LPM to new data. We then performed a co-clinical trial using small data to test if LPM could detect multiple therapeutics with both improved power and reduced animal numbers compared to conventional t-test approaches. Our data showed that LPM greatly increased the amount of information extracted from diffusion-weighted imaging, compared to cohort t-tests. LPM distinguished biological response rates between Calu6 tumors treated with 3 different therapies and between Calu6 tumors and 4 other xenograft models treated with radiotherapy. A simulated co-clinical trial using real data detected high precision per-tumor treatment effects in as few as 3 mice per cohort, with p-values as low as 1 in 10,000. These findings provide a route to simultaneously improve the information derived from preclinical imaging while reducing and refining the use of animals in cancer research.

6.
BMC Cancer ; 21(1): 354, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33794823

RESUMO

BACKGROUND: Patients with metastatic colorectal cancer are treated with cytotoxic chemotherapy supplemented by molecularly targeted therapies. There is a critical need to define biomarkers that can optimise the use of these therapies to maximise efficacy and avoid unnecessary toxicity. However, it is important to first define the changes in potential biomarkers following cytotoxic chemotherapy alone. This study reports the impact of standard cytotoxic chemotherapy across a range of circulating and imaging biomarkers. METHODS: A single-centre, prospective, biomarker-driven study. Eligible patients included those diagnosed with colorectal cancer with liver metastases that were planned to receive first line oxaliplatin plus 5-fluorouracil or capecitabine. Patients underwent paired blood sampling and magnetic resonance imaging (MRI), and biomarkers were associated with progression-free survival (PFS) and overall survival (OS). RESULTS: Twenty patients were recruited to the study. Data showed that chemotherapy significantly reduced the number of circulating tumour cells as well as the circulating concentrations of Ang1, Ang2, VEGF-A, VEGF-C and VEGF-D from pre-treatment to cycle 2 day 2. The changes in circulating concentrations were not associated with PFS or OS. On average, the MRI perfusion/permeability parameter, Ktrans, increased in response to cytotoxic chemotherapy from pre-treatment to cycle 2 day 2 and this increase was associated with worse OS (HR 1.099, 95%CI 1.01-1.20, p = 0.025). CONCLUSIONS: In patients diagnosed with colorectal cancer with liver metastases, treatment with standard chemotherapy changes cell- and protein-based biomarkers, although these changes are not associated with survival outcomes. In contrast, the imaging biomarker, Ktrans, offers promise to direct molecularly targeted therapies such as anti-angiogenic agents.


Assuntos
Biomarcadores Tumorais/metabolismo , Capecitabina/uso terapêutico , Fluoruracila/uso terapêutico , Oxaliplatina/uso terapêutico , Idoso , Capecitabina/farmacologia , Feminino , Fluoruracila/farmacologia , Humanos , Masculino , Metástase Neoplásica , Oxaliplatina/farmacologia , Estudos Prospectivos
7.
Cleft Palate Craniofac J ; 58(12): 1517-1525, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33535807

RESUMO

OBJECTIVE: To describe the incidence and timing of provider-specific interventions for children with isolated cleft palate. DESIGN: This was a retrospective cohort study involving review of medical records. SETTING: Multidisciplinary team care clinic at a tertiary academic children's hospital between January 2000 and July 2019. PATIENTS: Patients with isolated nonsyndromic cleft palate seen by an American Cleft Palate-Craniofacial Association-approved team; 138 children were included. MAIN OUTCOME MEASURES: Study outcomes included incidence of secondary velopharyngeal management, tympanostomy tube insertion, speech therapy, hearing loss, dental/orthodontic treatment, and psychology interventions. Provider-specific outcomes were calculated for patients at ages 0 to 3, 3 to 5, and >5 years. RESULTS: Median follow-up time was 7.0 years (interquartile range: 3.3-11.8 years). At their last team assessment, 42% of patients still had conductive hearing loss. The rate of tympanostomy tube insertions not done alongside a palatoplasty was highest for ages 3 to 5 and dropped after new American Academy of Otolaryngology-Head and Neck Surgery Foundation guidelines in 2013 (P = .015); 54% of patients received speech-language therapy during follow-up. Palatoplasty, psychology, and dental/orthodontic treatment were all less common than speech or ENT treatment (P < .01). Secondary palatoplasty was performed in 31 patients (22%). Patients who received speech, dental/orthodontic, or psychology intervention followed up longer than those who did not (9.8 vs 2.1 years, P < .001). CONCLUSION: Half of the patients terminated team follow-up by age 7, suggesting that burden of care outweighed perceived benefits of continued follow-up for many families. These results can be used to adjust protocols for children with isolated cleft palate.


Assuntos
Fissura Palatina , Insuficiência Velofaríngea , Criança , Pré-Escolar , Fissura Palatina/cirurgia , Humanos , Recém-Nascido , Ventilação da Orelha Média , Equipe de Assistência ao Paciente , Estudos Retrospectivos , Fala , Resultado do Tratamento , Insuficiência Velofaríngea/cirurgia
8.
Cancers (Basel) ; 13(2)2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33440685

RESUMO

Imaging biomarkers require technical, biological, and clinical validation to be translated into robust tools in research or clinical settings. This study contributes to the technical validation of radiomic features from magnetic resonance imaging (MRI) by evaluating the repeatability of features from four MR sequences: pre-contrast T1- and T2-weighted images, pre-contrast quantitative T1 maps (qT1), and contrast-enhanced T1-weighted images. Fifty-one patients with colorectal cancer liver metastases were scanned twice, up to 7 days apart. Repeatability was quantified using the intraclass correlation coefficient (ICC) and repeatability coefficient (RC), and the impact of non-Gaussian feature distributions and image normalisation was evaluated. Most radiomic features had non-Gaussian distributions, but Box-Cox transformations enabled ICCs and RCs to be calculated appropriately for an average of 97% of features across sequences. ICCs ranged from 0.30 to 0.99, with volume and other shape features tending to be most repeatable; volume ICC > 0.98 for all sequences. 19% of features from non-normalised images exhibited significantly different ICCs in pair-wise sequence comparisons. Normalisation tended to increase ICCs for pre-contrast T1- and T2-weighted images, and decrease ICCs for qT1 maps. RCs tended to vary more between sequences than ICCs, showing that evaluations of feature performance depend on the chosen metric. This work suggests that feature-specific repeatability, from specific combinations of MR sequence and pre-processing steps, should be evaluated to select robust radiomic features as biomarkers in specific studies. In addition, as different repeatability metrics can provide different insights into a specific feature, consideration of the appropriate metric should be taken in a study-specific context.

9.
Cleft Palate Craniofac J ; 57(7): 900-908, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31961207

RESUMO

OBJECTIVE: To report the incidences of secondary lip and nose operations, otolaryngology procedures, speech-language therapy, neurodevelopmental concerns, and dental and orthodontic issues in children with isolated cleft lip to inform multidisciplinary cleft team protocols. SETTING: An American Cleft Palate-Craniofacial Association-approved team at a tertiary academic children's hospital. DESIGN: Retrospective cohort study of patients evaluated through longitudinal clinic visits by a multidisciplinary cleft palate and craniofacial team between January 2000 and June 2018. PATIENTS, PARTICIPANTS: Children with nonsyndromic cleft lip with or without cleft alveolus (n = 92). RESULTS: Median age at final team visit was 4.9 years (interquartile range: 2.4-8.2 years). Secondary plastic surgery procedures were most common between ages 3 and 5 (135 per 1000 person-years), and the majority of these procedures were minor lip revisions. The rate of tympanostomy tube insertion was highest before age 3 (122 per 1000 person-years). By their final team visit, 88% of patients had normal hearing and 11% had only slight to mild conductive hearing loss. No patients had speech errors attributable to lip abnormalities. Psychological interventions, learning disabilities, and dental or orthodontic concerns were uncommon. CONCLUSIONS: Most patients with isolated cleft lip may not require long-term, longitudinal evaluation by cleft team specialists. Cleft teams should develop limited follow-up protocols for these children to improve resource allocation and promote value-based care in this patient population.


Assuntos
Fenda Labial , Fissura Palatina , Criança , Pré-Escolar , Fenda Labial/epidemiologia , Fenda Labial/cirurgia , Fissura Palatina/epidemiologia , Fissura Palatina/cirurgia , Humanos , Equipe de Assistência ao Paciente , Estudos Retrospectivos
10.
Clin Cancer Res ; 25(13): 3818-3829, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31053599

RESUMO

PURPOSE: Hypoxia is associated with poor prognosis and is predictive of poor response to cancer treatments, including radiotherapy. Developing noninvasive biomarkers that both detect hypoxia prior to treatment and track change in tumor hypoxia following treatment is required urgently. EXPERIMENTAL DESIGN: We evaluated the ability of oxygen-enhanced MRI (OE-MRI) to map and quantify therapy-induced changes in tumor hypoxia by measuring oxygen-refractory signals in perfused tissue (perfused Oxy-R). Clinical first-in-human study in patients with non-small cell lung cancer (NSCLC) was performed alongside preclinical experiments in two xenograft tumors (Calu6 NSCLC model and U87 glioma model). RESULTS: MRI perfused Oxy-R tumor fraction measurement of hypoxia was validated with ex vivo tissue pathology in both xenograft models. Calu6 and U87 experiments showed that MRI perfused Oxy-R tumor volume was reduced relative to control following single fraction 10-Gy radiation and fractionated chemoradiotherapy (P < 0.001) due to both improved perfusion and reduced oxygen consumption rate. Next, evaluation of 23 patients with NSCLC showed that OE-MRI was clinically feasible and that tumor perfused Oxy-R volume is repeatable [interclass correlation coefficient: 0.961 (95% CI, 0.858-0.990); coefficient of variation: 25.880%]. Group-wise perfused Oxy-R volume was reduced at 14 days following start of radiotherapy (P = 0.015). OE-MRI detected between-subject variation in hypoxia modification in both xenograft and patient tumors. CONCLUSIONS: These findings support applying OE-MRI biomarkers to monitor hypoxia modification, to stratify patients in clinical trials of hypoxia-modifying therapies, to identify patients with hypoxic tumors that may fail treatment with immunotherapy, and to guide adaptive radiotherapy by mapping regional hypoxia.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Hipóxia/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/metabolismo , Imageamento por Ressonância Magnética , Oxigênio/metabolismo , Animais , Biomarcadores , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Aumento da Imagem , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/radioterapia , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/normas , Camundongos , Medicina de Precisão/métodos , Medicina de Precisão/normas , Fluxo Sanguíneo Regional , Reprodutibilidade dos Testes , Carga Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Nutr Cancer ; 71(2): 301-311, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30661403

RESUMO

Natural falcarinol-type (FC-type) polyacetylenes are known to show anticancer activities. We studied the bioactivity of synthetic FC, 1,2-dihydrofalcarinol (FCH) and 3-acetoxyfalcarinol (FCA) and compared them with the natural bioactive polyacetylene [9,17-octadecadiene-12,14-diyne-1,11,16-triol,1-acetate] (DCA) isolated from Devil's club (DC) Oplopanax horridus. Antiproliferation activity of these polyacetylenes, along with DC inner stem bark 70% ethanol and water extracts, was tested on human pancreatic ductal adenocarcinoma cell lines PANC-1 and BxPC-3. Chemically synthesized FC and FCA showed consistent IC50 (50% inhibition concentration) and higher potency than DCA. FC and DCA's mechanism of action investigated by antibody array on apoptosis-associated genes, and cellular features confirmed by microscopy demonstrated that both compounds modulated genes related to pro-apoptosis, antiapoptosis, apoptosis, cell cycle, stress related, and death receptors. FC-type polyacetylenes with a terminal double bond (FC, FCA, and DCA) are potent inhibitors of pancreatic cancer cell proliferation compared to FCH with a terminal single bond. Liquid chromatography mass spectrometry confirmed the presence of FC and FCH in the inner stem bark of DC. For potential applications of FC-type polyacetylenes as anticancer agents, preparing them by chemical synthesis may provide an advantage over the labor intensive extraction process from raw plant material.


Assuntos
Carcinoma Ductal Pancreático/tratamento farmacológico , Di-Inos/farmacologia , Álcoois Graxos/farmacologia , Oplopanax/química , Neoplasias Pancreáticas/tratamento farmacológico , Polímero Poliacetilênico/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Neoplasias Pancreáticas/patologia , Casca de Planta/química , Extratos Vegetais/farmacologia
12.
Nat Commun ; 9(1): 4672, 2018 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-30405103

RESUMO

Oncological use of anti-angiogenic VEGF inhibitors has been limited by the lack of informative biomarkers. Previously we reported circulating Tie2 as a vascular response biomarker for bevacizumab-treated ovarian cancer patients. Using advanced MRI and circulating biomarkers we have extended these findings in metastatic colorectal cancer (n = 70). Bevacizumab (10 mg/kg) was administered to elicit a biomarker response, followed by FOLFOX6-bevacizumab until disease progression. Bevacizumab induced a correlation between Tie2 and the tumor vascular imaging biomarker, Ktrans (R:-0.21 to 0.47) implying that Tie2 originated from the tumor vasculature. Tie2 trajectories were independently associated with pre-treatment tumor vascular characteristics, tumor response, progression free survival (HR for progression = 3.01, p = 0.00014; median PFS 248 vs. 348 days p = 0.0008) and the modeling of progressive disease (p < 0.0001), suggesting that Tie2 should be monitored clinically to optimize VEGF inhibitor use. A vascular response is defined as a 30% reduction in Tie2; vascular progression as a 40% increase in Tie2 above the nadir. Tie2 is the first, validated, tumor vascular response biomarker for VEGFi.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Biomarcadores Tumorais/sangue , Neoplasias Colorretais/sangue , Neoplasias Colorretais/secundário , Receptor TIE-2/sangue , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Adulto , Idoso , Angiopoietina-2/metabolismo , Bevacizumab/farmacologia , Bevacizumab/uso terapêutico , Neoplasias Colorretais/irrigação sanguínea , Neoplasias Colorretais/tratamento farmacológico , Progressão da Doença , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Neovascularização Patológica/sangue , Prognóstico , Fator A de Crescimento do Endotélio Vascular/metabolismo
13.
Radiology ; 288(3): 739-747, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29869970

RESUMO

Purpose To cross-validate T1-weighted oxygen-enhanced (OE) MRI measurements of tumor hypoxia with intrinsic susceptibility MRI measurements and to demonstrate the feasibility of translation of the technique for patients. Materials and Methods Preclinical studies in nine 786-0-R renal cell carcinoma (RCC) xenografts and prospective clinical studies in eight patients with RCC were performed. Longitudinal relaxation rate changes (∆R1) after 100% oxygen inhalation were quantified, reflecting the paramagnetic effect on tissue protons because of the presence of molecular oxygen. Native transverse relaxation rate (R2*) and oxygen-induced R2* change (∆R2*) were measured, reflecting presence of deoxygenated hemoglobin molecules. Median and voxel-wise values of ∆R1 were compared with values of R2* and ∆R2*. Tumor regions with dynamic contrast agent-enhanced MRI perfusion, refractory to signal change at OE MRI (referred to as perfused Oxy-R), were distinguished from perfused oxygen-enhancing (perfused Oxy-E) and nonperfused regions. R2* and ∆R2* values in each tumor subregion were compared by using one-way analysis of variance. Results Tumor-wise and voxel-wise ∆R1 and ∆R2* comparisons did not show correlative relationships. In xenografts, parcellation analysis revealed that perfused Oxy-R regions had faster native R2* (102.4 sec-1 vs 81.7 sec-1) and greater negative ∆R2* (-22.9 sec-1 vs -5.4 sec-1), compared with perfused Oxy-E and nonperfused subregions (all P < .001), respectively. Similar findings were present in human tumors (P < .001). Further, perfused Oxy-R helped identify tumor hypoxia, measured at pathologic analysis, in both xenografts (P = .002) and human tumors (P = .003). Conclusion Intrinsic susceptibility biomarkers provide cross validation of the OE MRI biomarker perfused Oxy-R. Consistent relationship to pathologic analyses was found in xenografts and human tumors, demonstrating biomarker translation. Published under a CC BY 4.0 license. Online supplemental material is available for this article.


Assuntos
Carcinoma de Células Renais/fisiopatologia , Hipóxia/fisiopatologia , Aumento da Imagem/métodos , Neoplasias Renais/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Animais , Biomarcadores , Carcinoma de Células Renais/complicações , Carcinoma de Células Renais/diagnóstico por imagem , Modelos Animais de Doenças , Estudos de Viabilidade , Feminino , Humanos , Hipóxia/complicações , Hipóxia/diagnóstico por imagem , Rim/diagnóstico por imagem , Rim/patologia , Rim/fisiopatologia , Neoplasias Renais/complicações , Neoplasias Renais/diagnóstico por imagem , Masculino , Camundongos , Pessoa de Meia-Idade , Oxigênio , Estudos Prospectivos , Reprodutibilidade dos Testes
14.
Magn Reson Imaging ; 46: 98-105, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29154898

RESUMO

BACKGROUND: Solid tumours exhibit enhanced vessel permeability and fenestrated endothelium to varying degree, but it is unknown how this varies in patients between and within tumour types. Dynamic contrast-enhanced (DCE) MRI provides a measure of perfusion and permeability, the transfer constant Ktrans, which could be employed for such comparisons in patients. AIM: To test the hypothesis that different tumour types exhibit systematically different Ktrans. MATERIALS AND METHODS: DCE-MRI data were retrieved from 342 solid tumours in 230 patients. These data were from 18 previous studies, each of which had had a different analysis protocol. All data were reanalysed using a standardised workflow using an extended Tofts model. A model of the posterior density of median Ktrans was built assuming a log-normal distribution and fitting a simple Bayesian hierarchical model. RESULTS: 12 histological tumour types were included. In glioma, median Ktrans was 0.016min-1 and for non-glioma tumours, median Ktrans ranged from 0.10 (cervical) to 0.21min-1 (prostate metastatic to bone). The geometric mean (95% CI) across all the non-glioma tumours was 0.15 (0.05, 0.45)min-1. There was insufficient separation between the posterior densities to be able to predict the Ktrans value of a tumour given the tumour type, except that the median Ktrans for gliomas was below 0.05min-1 with 80% probability, and median Ktrans measurements for the remaining tumour types were between 0.05 and 0.4min-1 with 80% probability. CONCLUSION: With the exception of glioma, our hypothesis that different tumour types exhibit different Ktrans was not supported. Studies in which tumour permeability is believed to affect outcome should not simply seek tumour types thought to exhibit high permeability. Instead, Ktrans is an idiopathic parameter, and, where permeability is important, Ktrans should be measured in each tumour to personalise that treatment.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Meios de Contraste/química , Glioma/diagnóstico por imagem , Imageamento por Ressonância Magnética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Teorema de Bayes , Biomarcadores , Neoplasias Encefálicas/patologia , Permeabilidade Capilar , Feminino , Glioma/patologia , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Perfusão , Imagens de Fantasmas , Reprodutibilidade dos Testes , Estudos Retrospectivos , Razão Sinal-Ruído , Adulto Jovem
15.
Nutr Cancer ; 67(6): 954-64, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26221768

RESUMO

Devil's club Oplopanax horridus (DC) is a close relative of ginseng; its inner root and stem bark extract showed antiproliferation activity on human leukemia, ovarian, breast and colon cancer cells. We study here the effects of DC 70% ethanol extract alone, or in combination with cisplatin, gemcitabine, and paclitaxel on pancreatic endocrine HP62 and pancreatic ductal carcinoma PANC-1 and BxPC-3 cells. Antiproliferation activity assay, cell cycle analysis by flow cytometry, apoptosis-related markers by antibody array, and RT-PCR assay were used for this study. DC extract inhibited proliferation of HP62 with IC50 (50% inhibition concentration) at 0.037±0.002% (v/v), PANC-1 at 0.0058 ± 0.0004% and BxPC-3 at 0.021 ± 0.003%. DC at 0.0033% combined with 1 nM of paclitaxel showed inhibition synergy on PANC-1 cells with a combination index of 0.44. Apoptosis focused antibody array profile indicated upregulation of cytochrome C, claspin, cIAP-2 and HTRA2/Omi apoptosis-related markers in DC-treated HP62 and PANC-1. Our data suggest that DC acts through targeting the intrinsic mitochondrial apoptosis pathway in the pancreatic cancer cells. The high antiproliferation potency of DC on PANC-1 is potentially useful as an adjunct therapy for treating pancreatic cancer, which is known for developing resistance to conventional chemotherapeutics.


Assuntos
Proliferação de Células/efeitos dos fármacos , Oplopanax/química , Poli-Inos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Humanos , Concentração Inibidora 50 , Paclitaxel/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Transdução de Sinais , Gencitabina
16.
Influenza Other Respir Viruses ; 9(5): 255-62, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26073870

RESUMO

BACKGROUND: School-located influenza vaccination (SLV) programs have the potential to mass-vaccinate all enrolled children, but parental consent is required. OBJECTIVE: To examine parental attitudes and determine predictors of parental consent for vaccination of schoolchildren through SLV programs. PATIENTS/METHODS: Surveys were distributed to parents of 4517 children during 2009-2010 (year 1) and 4414 children during 2010-2011 (year 2) in eight elementary schools in conjunction with a SLV program. RESULTS: Participants included 1259 (27·9%) parents in year 1 and 1496 (33·9%) in year 2. Parental consent for 2009 H1N1, 2009 seasonal, and 2010 seasonal influenza vaccines was obtained from 738 (70·8%), 673 (64·5%), and 1151 (77·2%) respondents, respectively. During the 2009 pandemic, respondents concerned about influenza severity were twice as likely to consent for the 2009 H1N1 vaccination compared to unconcerned respondents (OR 2·04, 95% CI:1·19-3·51). During year 2, factors that predicted parental consent were the perception of high susceptibility to influenza infection (OR 2·19, 95% CI:1·50-3·19) and high benefit of vaccine (OR 2·23, 95% CI:1·47-3·40). In both years, college-educated parents were more likely to perceive vaccine risks (year 1: 83·6 versus 61·5%, P < 0·001 and year 2: 81·1% versus 60·6%, P < 0·001) and less likely to consent for seasonal influenza vaccine (year 1: OR 0·69, 95% CI:0·53-0·89 and year 2: OR 0·61, 95% CI:0·47-0·78) compared to non-college-educated parents. CONCLUSIONS: Parents who appreciate the risks of influenza and benefits of vaccination are more likely to consent for SLV. More research is needed to determine how to address heightened safety concerns among college-educated parents.


Assuntos
Vacinas contra Influenza/administração & dosagem , Influenza Humana/prevenção & controle , Pais/psicologia , Vacinação/psicologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Programas de Imunização , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Humana/psicologia , Influenza Humana/virologia , Masculino , Percepção , Instituições Acadêmicas , Estados Unidos , Saúde da População Urbana , Adulto Jovem
17.
Planta Med ; 80(8-9): 662-70, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24922275

RESUMO

This study was conducted to employ an ovarian cancer Ovcar 10 three-dimensional model to assess the antiproliferation activity of the medicinal plant Devil's club, Oplopanax horridus, and its active compound, alone and in combination, with chemotherapeutic agents compared to Ovcar 10 two-dimensional cells grown as monolayer cells. Ovcar 10 three-dimensional spheroids were prepared with a rotary cell culture system. Cell counting kit-8 assessed the antiproliferation activity. Apoptosis-related gene expression in three-dimensional spheroids and two- dimensional cells was analyzed with an apoptosis antibody array. Flow cytometry was used to analyze the cell cycle. Ovcar 10 cells formed compact three-dimensional spheroids after 5 days of culture in a rotary culture system. Ovcar 10 three-dimensional spheroids were significantly more resistant to killing by Devil's club extract, its active compound alone, gemcitabine, and paclitaxel, but not cisplatin compared to two-dimensional cells, with IC50 levels closer to that observed in vivo. Devil's club extract and its active compound alone significantly enhanced the antiproliferation activity of cisplatin and gemcitabine at some concentrations, but did not affect the activity of paclitaxel. A number of apoptosis-related genes were differentially expressed in three-dimensional spheroids, two-dimensional cells, and cells treated with Devil's club extract compared to untreated controls. In three-dimensional spheroids, the proportion of cells in the G2/M phase was slightly increased and the S phase was slightly decreased compared to two-dimensional cells. Ovcar 10 cells in three-dimensional spheroids altered the expression of multiple apoptosis-related genes, which may have contributed to the increased resistance of the cells to some drugs.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Oplopanax/química , Neoplasias Ovarianas/tratamento farmacológico , Extratos Vegetais/farmacologia , Esferoides Celulares/efeitos dos fármacos , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cisplatino/farmacologia , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Feminino , Humanos , Neoplasias Ovarianas/patologia , Paclitaxel/farmacologia , Casca de Planta/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Proteoma , Células Tumorais Cultivadas/efeitos dos fármacos , Gencitabina
18.
Pancreas ; 43(1): 128-34, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24326367

RESUMO

OBJECTIVES: B7-H4 is a negative coregulatory molecule known to be involved in immune response. We study here B7-H4 expression and its possible role in diabetes and cancer development. METHODS: Formalin-fixed, paraffin-processed pancreas samples from patients with type 1 diabetes (T1D), insulinoma, pancreatic ductal adenocarcinoma (PDAC), and normal organ donors were studied by bright-field and multifluorescence immunohistochemistry to examine B7-H4 expression and its colocalization with islet endocrine hormones. Quantitative RT-PCR and Western blot assay were used to examine B7-H4 mRNA and protein expression in the islet and exocrine tissues from normal donors and pancreatic cancer cell lines. RESULTS: B7-H4 protein expression in islet ß cells is decreased in T1D and PDAC, but increased in insulinoma patients when compared to normal controls; the changes in B7-H4 expression are concomitant with insulin expression on the islet ß cells. The insulin/B7-H4 colocalization on the ß cells, expressed in colocalization coefficient Pearson r, is also changed in these islets. CONCLUSIONS: Our observation of altered B7-H4 expression, concomitant with insulin expression, in the pancreatic islets of T1D, PDAC, and insulinoma patients when compared to normal controls suggests that B7-H4 pathway might play an important role in maintenance of ß-cell function, but its exact role remains to be explored.


Assuntos
Adenocarcinoma/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Células Secretoras de Insulina/metabolismo , Insulinoma/metabolismo , Neoplasias Pancreáticas/metabolismo , Inibidor 1 da Ativação de Células T com Domínio V-Set/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/patologia , Western Blotting , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular , Linhagem Celular Tumoral , Diabetes Mellitus Tipo 1/genética , Expressão Gênica , Humanos , Imuno-Histoquímica , Insulina/genética , Insulina/metabolismo , Insulinoma/genética , Insulinoma/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Inibidor 1 da Ativação de Células T com Domínio V-Set/genética
19.
Magn Reson Med ; 71(5): 1854-62, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23798369

RESUMO

PURPOSE: There is a clinical need for noninvasive, nonionizing imaging biomarkers of tumor hypoxia and oxygenation. We evaluated the relationship of T1 -weighted oxygen-enhanced magnetic resonance imaging (OE-MRI) measurements to histopathology measurements of tumor hypoxia in a murine glioma xenograft and demonstrated technique translation in human glioblastoma multiforme. METHODS: Preclinical evaluation was performed in a subcutaneous murine human glioma xenograft (U87MG). Animals underwent OE-MRI followed by dynamic contrast-enhanced MRI (DCE-MRI) and histological measurement including reduced pimonidazole adducts and CD31 staining. Area under the curve (AUC) was measured for the R1 curve for OE-MRI and the gadolinium concentration curve for DCE-MRI. Clinical evaluation in five patients used analogous imaging protocols and analyses. RESULTS: Changes in AUC of OE-MRI (AUCOE ) signal were regionally heterogeneous across all U87MG tumors. Tumor regions with negative AUCOE typically had low DCE-MRI perfusion, had positive correlation with hypoxic area (P = 0.029), and had negative correlation with vessel density (P = 0.004). DCE-MRI measurements did not relate to either hypoxia or vessel density in U87MG tumors. Clinical data confirmed comparable signal changes in patients with glioblastoma. CONCLUSION: These data support further investigation of T1 -weighted OE-MRI to identify regional tumor hypoxia. The quantification of AUCOE has translational potential as a clinical biomarker of hypoxia.


Assuntos
Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Glioma/metabolismo , Imageamento por Ressonância Magnética/métodos , Oximetria/métodos , Oxigênio/metabolismo , Animais , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/patologia , Hipóxia Celular , Linhagem Celular Tumoral , Feminino , Glioblastoma/patologia , Glioma/patologia , Humanos , Camundongos , Camundongos Nus , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Distribuição Tecidual
20.
Phytomedicine ; 19(5): 436-43, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22325591

RESUMO

Rosemary (Rosmarinus officinalis L.) is a popular culinary/medicinal herb. Recent studies have shown it has pharmacologic activities for cancer chemoprevention and therapy. This study evaluated the antiproliferation activity of rosemary extract (RE) against human ovarian cancer cells, and whether the extract and its three main active ingredients carnosol (CS), carnosic acid (CA) and rosmarinic acid (RA) can enhance the antiproliferation activity of cisplatin (CDDP). Our study showed that RE has significant antiproliferation activity on human ovarian cancer A2780 and its CDDP resistant daughter cell line A2780CP70, with IC(50) (50% inhibitory concentration) estimated at 1/1000 and 1/400 dilutions respectively. RE enhanced the antiproliferation effect with CDDP on both A2780 and A2780CP70 cells. A2780 cells were consistently more sensitive to CS, CA, and RA than A2780CP70 cells between 2.5 and 20µg/ml. CS and RA also showed synergistic antiproliferation effect with CDDP on A2780 cells at some concentrations. RE treated by ultrafiltration, dialysis, and removal of phenolics lost the antiproliferation activity suggested that the activity resides in phenolics with MW<1000Da. Apoptosis array study of A2780 cells treated with RE showed that the expression of a number of genes regulating apoptosis were modulated by the treatment. This study showed that RE inhibited the proliferation of ovarian cancer cell lines by affecting the cell cycle at multiple phases. It induced apoptosis by modifying the expression of multiple genes regulating apoptosis, and holds potential as an adjunct to cancer chemotherapy.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Cisplatino/farmacologia , Extratos Vegetais/farmacologia , Rosmarinus/química , Abietanos/química , Abietanos/isolamento & purificação , Abietanos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cinamatos/química , Cinamatos/isolamento & purificação , Cinamatos/farmacologia , Depsídeos/química , Depsídeos/isolamento & purificação , Depsídeos/farmacologia , Quimioterapia Combinada , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Neoplasias Ovarianas , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Ácido Rosmarínico
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