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1.
Neoplasma ; 70(4): 555-565, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37789778

RESUMO

Hepatocellular carcinoma (HCC) is a primary liver cancer characterized by high invasiveness, metastasis, and poor prognosis, which lacks effective treatments. Although the role of miR-192 in HCC development has been recognized, the underlying molecular mechanism is still poorly understood. This study aimed to explore the impact of mir-192 on HCC and its potential as a therapeutic strategy. Wound healing assay, Transwell assay, CCK-8 assay, and flow cytometry were performed to detect the impact of miR-192 on HCC cell metastasis, invasion, proliferation, and apoptosis, respectively. q-PCR and western blot were applied to measure the relative mRNA and protein expression of the GSK3ß/Wnt/ß-catenin pathway in miR-192-overexpressing cell lines. Immunofluorescence was carried out to detect the nuclear translocation of ß-catenin. starBase website and dual luciferase reporter assay were used to verify the interaction between miR-192 and the target gene WNT10B 3'-untranslated region (3'-UTR) of the Wnt pathway. In addition, we developed algin/polyethyleneimine@miR-192 (AG/PEI@miR-192) nanohydrogel for in vivo delivery of miR-192-agomir. The results revealed that overexpressed miR-192 reduced the expression of HCC cell surface markers CD90, EpCAM, and CD133. Moreover, miR-192 overexpression inhibited HCC cell metastasis, invasion, and proliferation, promoted cell apoptosis, and reduced GSK3ß/Wnt/ß-catenin pathway expression. Additionally, AG/PEI@miR-192 exhibited good drug release and tumor inhibition. In conclusion, our study suggested that miR-192 inhibits HCC development by suppressing the GSK3ß/Wnt/ß-catenin pathway and proposed a promising hydrogel-based miR-192 delivery approach to hinder tumor growth.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Humanos , Carcinoma Hepatocelular/patologia , Via de Sinalização Wnt/genética , Neoplasias Hepáticas/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , beta Catenina/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Hidrogéis/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética
2.
Taiwan J Obstet Gynecol ; 62(1): 31-39, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36720546

RESUMO

OBJECTIVE: Laparoscopic box simulation training is widely recognized as an assessment tool to facilitate psychomotor skills especially for novice surgeons. However, current commercialized training modules including pegs, gauze, clips, pins etc. are generally costly and relatively inaccessible. We introduce a simple and pioneer surgical training drill, the Origami Box Folding Exercise (OBFE), based on the validated evaluating system of objective structured assessment of technical skills (OSATS) constructed with the scoring system of procedure-specific checklist (PSC) and global rating scale (GRS). MATERIALS AND METHODS: Face and content validation of the OBFE and OSATS are evaluated by five endoscopic experts from two medical centers in Taiwan. This is a prospective observational study analyzing the pre-test/post-test result of OBFE from 37 participants in two individual workshops as training and evaluating method for laparoscopic psychomotor skills. Both the pre and post tests are video recorded with a time limit of 5 min graded by two independent evaluators based on the OSATS scoring system. RESULTS: The reliability of PSC, GRS, and intergroup value between PSC and GRS were 0.923, 0.926 and 0.933, respectively. Inter-rater reliability of PSC, GRS, and both were 0.985, 0.932 and 0.977, respectively. Construct validity of PSC and GRS were statistically significant, with p-value 0.006 and 0.001, respectively. CONCLUSION: OBFE enhances laparoscopic psychomotor skills with requirement of a single piece of paper. The associated OSATS tool for a 5-min OBFE test was validated. OBFE training is an efficient training and assessment system to promote psychomotor skills in laparoscopic box simulation drill which requires simple and economical preparation.


Assuntos
Internato e Residência , Laparoscopia , Treinamento por Simulação , Humanos , Reprodutibilidade dos Testes , Laparoscopia/métodos , Treinamento por Simulação/métodos , Estudos Prospectivos
3.
J Minim Invasive Gynecol ; 29(11): 1219-1220, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36038062

RESUMO

STUDY OBJECTIVE: Although a pericervical tourniquet helped reduce blood loss in myomectomy [1], a technique of triple tourniquets was more influential in occluding the uterine vessel networks [2,3]. This video demonstrates the procedures of laparoscopic triple-tourniquet constriction with the number 1 suture around the uterine isthmic portion and bilateral infundibulopelvic ligaments [4] in a case of robotic myomectomy. DESIGN: A step-by-step, narrated video demonstration. SETTING: A university hospital. INTERVENTIONS: Robotic myomectomy was scheduled for a patient with menorrhagia. Magnetic resonance imaging revealed 8 uterine myomas; the maximal one was 9.1 × 8.4 × 8.6 cm in dimension. Our robotic settings included 3 ports: fenestrated bipolar in the left lower quadrant, spatula or mega needle holder in the right lower quadrant, and an umbilical glove port accessible for lens and assisted instruments. A number 1 Monocryl (Ethicon, Bridgewater, NJ) was introduced from the suprapubic area extracorporeally; then, the needle penetrated through bilateral avascular zones of broad ligaments at the isthmic level and with a sliding tie made anteriorly to the uterus. The isthmic tourniquet-we also named it as the hangman's tourniquet-was tightened by manually tensioning the suture extracorporeally and pushing down the knot intracorporeally. Bilateral infundibulopelvic tourniquets were placed by using sliding ties of 1-0 Monocryl as well. With the total occlusion of uterine vessel networks, the uterus should retain only minimal blood flow. During the enucleation of uterine myomas, the tourniquet may loosen because of newly developed, unoccupied space with increasing bleeding; therefore, the tourniquet should be tightened up regularly throughout the surgery. After the repair of all the uterine wounds, we removed the 3 tourniquets. CONCLUSION: The convenient and adjustable triple-tourniquet constriction is a safe and feasible laparoscopic technique to block the vessel networks temporally in uterine-preserving surgery.


Assuntos
Laparoscopia , Leiomioma , Mioma , Miomectomia Uterina , Neoplasias Uterinas , Feminino , Humanos , Miomectomia Uterina/métodos , Torniquetes , Neoplasias Uterinas/cirurgia , Neoplasias Uterinas/patologia , Constrição , Leiomioma/cirurgia , Leiomioma/patologia , Laparoscopia/métodos , Perda Sanguínea Cirúrgica/prevenção & controle , Constrição Patológica/cirurgia , Mioma/cirurgia
4.
Int J Mol Sci ; 22(21)2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34768813

RESUMO

Liver disorders are a major health concern. Saikosaponin-d (SSd) is an effective active ingredient extracted from Bupleurum falcatum, a traditional Chinese medicinal plant, with anti-inflammatory and antioxidant properties. However, its hepatoprotective properties and underlying mechanisms are unknown. We investigated the effects and underlying mechanisms of SSd treatment for thioacetamide (TAA)-induced liver injury and high-fat-diet (HFD)-induced non-alcoholic fatty liver disease (NAFLD) in male C57BL/6 mice. The SSd group showed significantly higher food intake, body weight, and hepatic antioxidative enzymes (catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD)) and lower hepatic cyclooxygenase-2 (COX-2), serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, and fibroblast growth factor-21 (FGF21) compared with controls, as well as reduced expression of inflammation-related genes (nuclear factor kappa B (NF-κB) and inducible nitric oxide synthase (iNOS)) messenger RNA (mRNA). In NAFLD mice, SSd reduced serum ALT, AST, triglycerides, fatty acid-binding protein 4 (FABP4) and sterol regulatory element-binding protein 1 (SREBP1) mRNA, and endoplasmic reticulum (ER)-stress-related proteins (phosphorylated eukaryotic initiation factor 2α subunit (p-eIF2α), activating transcription factor 4 (ATF4), and C/EBP homologous protein (CHOP). SSd has a hepatoprotective effect in liver injury by suppressing inflammatory responses and acting as an antioxidant.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Doença Hepática Induzida por Substâncias e Drogas , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Ácido Oleanólico/análogos & derivados , Saponinas/farmacologia , Alanina Transaminase/análise , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Aspartato Aminotransferases/análise , Catalase/análise , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/metabolismo , Ácido Oleanólico/farmacologia , Ácido Oleanólico/uso terapêutico , Saponinas/uso terapêutico , Superóxido Dismutase/análise , Tioacetamida/toxicidade
5.
Molecules ; 26(15)2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34361836

RESUMO

Zotarolimus is a semi-synthetic derivative of rapamycin and an inhibitor of mammalian target of rapamycin (mTOR) signaling. Currently, zotarolimus is used to prolong the survival time of organ grafts, but it is also a novel immunosuppressive agent with potent anti-proliferative activity. Here, we examine the anti-tumor effect of zotarolimus, alone and in combination with 5-fluorouracil, on HCT-116 colorectal adenocarcinoma cells implanted in BALB/c nude mice. Compared with the control mice, mice treated with zotarolimus or zotarolimus combined with 5-FU showed retarded tumor growth; increased tumor apoptosis through the enhanced expression of cleaved caspase 3 and extracellular signal-regulated kinase (ERK) phosphorylation; reduced inflammation-related factors such as IL-1ß, TNF-α, and cyclooxygenase-2 (COX-2) protein; and inhibited metastasis-related factors such as CD44, epidermal growth factor receptor (EGFR), transforming growth factor ß (TGF-ß), and vascular endothelial growth factor (VEGF). Notably, mice treated with a combination of zotarolimus and 5-FU showed significantly retarded tumor growth, reduced tumor size, and increased tumor inhibition compared with mice treated with 5-FU or zotarolimus alone, indicating a strong synergistic effect. This in vivo study confirms that zotarolimus or zotarolimus combined with 5-FU can be used to retard colorectal adenocarcinoma growth and inhibit tumorigenesis. Our results suggest that zotarolimus may increase the chemo-sensitization of tumor cells. Therefore, zotarolimus alone and zotarolimus combined with 5-FU may be potential anti-tumor agents in the treatment of human colon adenocarcinoma. Future research on zotarolimus may lead to the development of new therapeutic strategies.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Animais , Apoptose , Proliferação de Células , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Fluoruracila/administração & dosagem , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Sirolimo/administração & dosagem , Sirolimo/análogos & derivados , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Mar Pollut Bull ; 172: 112811, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34403924

RESUMO

In Taiwan, freshwater clams (Corbicula fluminea) and hard clams (Meretrix lusoria) are the most frequently raised shellfish in land-based pond aquaculture, but research on the accumulation of organochlorine pesticides (OCPs) in these shellfish is limited. We detected the levels of 14 OCPs in 62 shellfish from Taiwanese aquafarms by performing gas chromatography-tandem mass spectrometry. OCP residues were detected in 4.84% of the samples including readings of 0.04 mg/kg chlordane (in a freshwater clam), 0.03 mg/g p,p'-DDE (in a freshwater clam), and 0.02 mg/g p,p'-DDE (in a hard clam). However, the associated estimated daily intake values were less than the acceptable daily intake levels of chlordane and p,p'-DDE Therefore, the consumption of these shellfish presents no immediate health risks. Our findings contribute to food safety and serve as a reference for OCP screenings for aquatic shellfish.


Assuntos
Hidrocarbonetos Clorados , Praguicidas , Poluentes Químicos da Água , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Medição de Risco , Frutos do Mar , Taiwan , Poluentes Químicos da Água/análise
7.
Int J Mol Sci ; 22(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206460

RESUMO

Clozapine is widely employed in the treatment of schizophrenia. Compared with that of atypical first-generation antipsychotics, atypical second-generation antipsychotics such as clozapine have less severe side effects and may positively affect obesity and blood glucose level. However, no systematic study of clozapine's adverse metabolic effects-such as changes in kidney and liver function, body weight, glucose and triglyceride levels, and retinopathy-was conducted. This research investigated how clozapine affects weight, the bodily distribution of chromium, liver damage, fatty liver scores, glucose homeostasis, renal impairment, and retinopathy in mice fed a high fat diet (HFD). We discovered that obese mice treated with clozapine gained more weight and had greater kidney, liver, and retroperitoneal and epididymal fat pad masses; higher daily food efficiency; higher serum or hepatic triglyceride, aspartate aminotransferase, alanine aminotransferase, blood urea nitrogen, and creatinine levels; and higher hepatic lipid regulation marker expression than did the HFD-fed control mice. Furthermore, the clozapine group mice exhibited insulin resistance, poorer insulin sensitivity, greater glucose intolerance, and less Akt phosphorylation; their GLUT4 expression was lower, they had renal damage, more reactive oxygen species, and IL-1 expression, and, finally, their levels of antioxidative enzymes (superoxide dismutase, glutathione peroxidase, and catalase) were lower. Moreover, clozapine reduced the thickness of retinal cell layers and increased iNOS and NF-κB expression; a net negative chromium balance occurred because more chromium was excreted through urine, and this influenced chromium mobilization, which did not help overcome the hyperglycemia. Our clozapine group had considerably higher fatty liver scores, which was supported by the findings of lowered adiponectin protein levels and increased FASN protein, PNPLA3 protein, FABP4 mRNA, and SREBP1 mRNA levels. We conclude that clozapine can worsen nonalcoholic fatty liver disease, diabetes, and kidney and retinal injury. Therefore, long-term administration of clozapine warrants higher attention.


Assuntos
Cromo/deficiência , Clozapina/farmacologia , Intolerância à Glucose/metabolismo , Nefropatias/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/metabolismo , Doenças Retinianas/metabolismo , Adipócitos/metabolismo , Animais , Biomarcadores , Pesos e Medidas Corporais , Modelos Animais de Doenças , Proteínas de Ligação a Ácido Graxo/genética , Imunofluorescência , Expressão Gênica , Regulação da Expressão Gênica , Imuno-Histoquímica , Insulina/metabolismo , Nefropatias/etiologia , Fígado/metabolismo , Camundongos , Camundongos Obesos , Óxido Nítrico Sintase Tipo II , Hepatopatia Gordurosa não Alcoólica/etiologia , Obesidade/complicações , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Doenças Retinianas/etiologia , Proteína de Ligação a Elemento Regulador de Esterol 1/genética
8.
Molecules ; 26(7)2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33808318

RESUMO

Liver disorders have been recognized as one major health concern. Fucoidan, a sulfated polysaccharide extracted from the brown seaweed Fucus serratus, has previously been reported as an anti-inflammatory and antioxidant. However, the discovery and validation of its hepatoprotective properties and elucidation of its mechanisms of action are still unknown. The objective of the current study was to investigate the effect and possible modes of action of a treatment of fucoidan against thioacetamide (TAA)-induced liver injury in male C57BL/6 mice by serum biochemical and histological analyses. The mouse model for liver damage was developed by the administration of TAA thrice a week for six weeks. The mice with TAA-induced liver injury were orally administered fucoidan once a day for 42 days. The treated mice showed significantly higher body weights; food intakes; hepatic antioxidative enzymes (catalase, glutathione peroxidase (GPx), and superoxide dismutase (SOD)); and a lower serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and C-reactive protein (CRP) levels. Additionally, a reduced hepatic IL-6 level and a decreased expression of inflammatory-related genes, such as cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) mRNA was observed. These results demonstrated that fucoidan had a hepatoprotective effect on liver injury through the suppression of the inflammatory responses and acting as an antioxidant. In addition, here, we validated the use of fucoidan against liver disorders with supporting molecular data.


Assuntos
Anti-Inflamatórios , Antioxidantes , Doença Hepática Crônica Induzida por Substâncias e Drogas/tratamento farmacológico , Fígado/efeitos dos fármacos , Polissacarídeos , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologia , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Citocinas/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Polissacarídeos/administração & dosagem , Polissacarídeos/farmacologia , Tioacetamida/toxicidade
9.
Neuroimage ; 218: 116978, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32447015

RESUMO

Perivascular spaces (PVSs) are fluid-filled spaces surrounding penetrating blood vessels in the brain and are an integral pathway of the glymphatic system. A PVS and the enclosed blood vessel are commonly visualized as a single vessel-like complex (denoted as PVSV) in high-resolution MRI images. Quantitative characterization of the PVSV morphology in MRI images in healthy subjects may serve as a reference for detecting disease related PVS and/or blood vessel alterations in patients with brain diseases. To this end, we evaluated the age dependences, spatial heterogeneities, and dynamic properties of PVSV morphological features in 45 healthy subjects (21-55 years old), using an ultra-high-resolution three-dimensional transverse relaxation time weighted MRI sequence (0.41 â€‹× â€‹0.41 â€‹× â€‹0.4 â€‹mm3) at 7T. Quantitative PVSV parameters, including apparent diameter, count, volume fraction (VF), and relative contrast to noise ratio (rCNR) were calculated in the white matter and subcortical structures. Dynamic changes were induced by carbogen breathing which are known to induce vasodilation and increase the blood oxygenation level in the brain. PVSV count and VF significantly increased with age in basal ganglia (BG), so did rCNR in BG, midbrain, and white matter (WM). Apparent PVSV diameter also showed a positive association with age in the three brain regions, although it did not reach statistical significance. The PVSV VF and count showed large inter-subject variations, with coefficients of variation ranging from 0.17 to 0.74 after regressing out age and gender effects. Both apparent diameter and VF exhibited significant spatial heterogeneity, which cannot be explained solely by radio-frequency field inhomogeneities. Carbogen breathing significantly increased VF in BG and WM, and rCNR in thalamus, BG, and WM compared to air breathing. Our results are consistent with gradual dilation of PVSs with age in healthy adults. The PVSV morphology exhibited spatial heterogeneity and large inter-subject variations and changed during carbogen breathing compared to air breathing.


Assuntos
Vasos Sanguíneos/anatomia & histologia , Sistema Glinfático/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos , Adulto , Envelhecimento/patologia , Feminino , Voluntários Saudáveis , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Clin Genitourin Cancer ; 18(5): 378-386.e1, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32147364

RESUMO

INTRODUCTION: Computed tomography (CT) has limited diagnostic accuracy for staging of muscle-invasive bladder cancer (MIBC). [18F] Fluorodeoxyglucose positron emission tomography (FDG-PET)/magnetic resonance imaging (MRI) is a novel imaging modality incorporating functional imaging with improved soft tissue characterization. This pilot study evaluated the use of preoperative FDG-PET/MRI for staging of MIBC. PATIENTS AND METHODS: Twenty-one patients with MIBC with planned radical cystectomy were enrolled. Two teams of radiologists reviewed FDG-PET/MRI scans to determine: (1) presence of primary bladder tumor; and (2) lymph node involvement and distant metastases. FDG-PET/MRI was compared with cystectomy pathology and computed tomography (CT). RESULTS: Eighteen patients were included in the final analysis, most (72.2%) of whom received neoadjuvant chemotherapy. Final pathology revealed 10 (56%) patients with muscle invasion and only 3 (17%) patients with lymph node involvement. Clustered analysis of FDG-PET/MRI radiology team reads revealed a sensitivity of 0.80 and a specificity of 0.56 for detection of the primary tumor with a sensitivity of 0 and a specificity of 1.00 for detection of lymph node involvement when compared with cystectomy pathology. CT imaging demonstrated similar rates in evaluation of the primary tumor (sensitivity, 0.91; specificity, 0.43) and lymph node involvement (sensitivity, 0; specificity, 0.93) when compared with pathology. CONCLUSIONS: This pilot single-institution experience of FDG-PET/MRI for preoperative staging of MIBC performed similar to CT for the detection of the primary tumor; however, the determination of lymph node status was limited by few patients with true pathologic lymph node involvement. Further studies are needed to evaluate the potential role for FDG-PET/MRI in the staging of MIBC.


Assuntos
Neoplasias da Bexiga Urinária , Fluordesoxiglucose F18 , Humanos , Metástase Linfática , Imageamento por Ressonância Magnética , Músculos/patologia , Estadiamento de Neoplasias , Projetos Piloto , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Neoplasias da Bexiga Urinária/patologia
11.
Artigo em Inglês | MEDLINE | ID: mdl-34734215

RESUMO

In this paper, we introduce a technique for super-resolution reconstruction of diffusion MRI, harnessing fiber-continuity (FC) as a constraint in a global whole-brain optimization framework. FC is a biologically-motivated constraint that relates orientation information between neighboring voxels. We show that it can be used to effectively constrain the inverse problem of recovering high-resolution data from low-resolution data. Since voxels are inter-related by FC, we devise a global optimization framework that allows solutions pertaining to all voxels to be solved simultaneously. We demonstrate that the proposed super-resolution framework is effective for diffusion MRI data of a glioma patient, a healthy subject, and a macaque.

12.
Med Phys ; 47(3): 1199-1214, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31834641

RESUMO

PURPOSE: Magnetic resonance fingerprinting (MRF) provides quantitative T1/T2 maps, enabling applications in clinical radiotherapy such as large-scale, multi-center clinical trials for longitudinal assessment of therapy response. We evaluated the feasibility of a quantitative three-dimensional-MRF (3D-MRF) towards its radiotherapy applications of primary brain tumors. METHODS: A fast whole-brain 3D-MRF sequence initially developed for diagnostic radiology was optimized using flexible body coils, which is the typical MR imaging setup for radiotherapy treatment planning and for MR imaging (MRI)-guided treatment delivery. Optimization criteria included the accuracy and the precision of T1/T2 quantifications of polyvinylpyrrolidone (PVP) solutions, compared to those from the 3D-MRF using a 32-channel head coil. The accuracy of T1/T2 quantifications from the optimized MRF was first examined in healthy volunteers with two different coil setups. The intra- and inter-scanner variations of image intensity from the optimized sequence were quantified by longitudinal scans of the PVP solutions on two 3T scanners. Using a 3D-printed MRI geometry phantom, susceptibility-induced distortion with the optimized 3D-MRF was quantified as the Dice coefficient of phantom contours, compared to those from CT images. By introducing intentional head motion during 10% of the scan, the robustness of the optimized 3D-MRF towards motion was evaluated through visual inspection of motion artifacts and through quantitative analysis of image sharpness in brain MRF maps. RESULTS: The optimized sequence acquired whole-brain T1, T2 and proton density maps and with a resolution of 1.2 × 1.2 × 3 mm3 in 10 min, similar to the total acquisition time of 3D T1- and T2-weighted images of the same resolution. In vivo T1 and T2 values of the white and gray matter were consistent with literature. The intra- and inter-scanner variability of the intensity-normalized MRF T1 was 1.0% ± 0.7% and 2.3% ± 1.0% respectively, in contrast to 5.3% ± 3.8% and 3.2% ± 1.6% from the normalized T1-weighted MRI. Repeatability and reproducibility of MRF T1 were independent of intensity normalization. Both phantom and human data demonstrated that the optimized 3D-MRF is more robust to subject motion and artifacts from subject-specific susceptibility difference. Compared to CT contours, the Dice coefficient of phantom contours from 3D-MRF was 0.93, improved from 0.87 from the T1-weighted MRI. CONCLUSION: Compared to conventional MRI, the optimized 3D-MRF demonstrated improved repeatability across time points and reproducibility across scanners for better tissue quantification, as well as improved robustness to subject-specific susceptibility and motion artifacts under a typical MR imaging setup for radiotherapy. More importantly, quantitative MRF T1/T2 measurements lead to promising potentials towards longitudinal quantitative assessment of treatment response for better adaptive therapy and for large-scale, multi-center clinical trials.


Assuntos
Encéfalo/diagnóstico por imagem , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Radioterapia Guiada por Imagem/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/radioterapia , Humanos
13.
J Am Soc Mass Spectrom ; 30(12): 2762-2770, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31713172

RESUMO

Organic nitrates in the atmosphere are associated with photochemical pollution and are the main components of secondary organic aerosols, which are related to haze. An efficient method for determining organic nitrates in atmospheric fine particles (PM2.5) was established using synthesized standards. Four alkyl (C7-C10) nitrates and three aromatic nitrates (tolyl nitrate, phenethyl nitrate, and p-xylyl nitrate) were synthesized and characterized by 1H and 13C nuclear magnetic resonance spectroscopy. The optimal ions for quantifying and confirming the identities of the analytes were identified by analyzing the standards by gas chromatography tandem mass spectrometry. The tandem mass spectrometer was a triple quadrupole instrument. This method can obtain more accurate information of organic nitrates than on-line methods. Spiked recovery tests were performed using three spike concentrations, and the recoveries were 61.0-111.4 %, and the relative standard deviations were < 8.2% for all of the analytes. Limits of detection and quantification were determined, and the linearity of the method for each analyte was assessed. The applicability of the method was demonstrated by analyzing six PM2.5 samples. Overall, 87% of the analytes were detected in the samples. Phenethyl nitrate, heptyl nitrate, and octyl nitrate were detected in every sample. Phenethyl nitrate was found at a higher mean concentration (3.23 ng/m3) than the other analytes.

14.
World J Nucl Med ; 17(4): 213-218, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30505216

RESUMO

With the spread of positron emission tomography/magnetic resonance (PET/MR), the question of comparability of studies becomes important. We aim to determine whether PET/MR and PET/computed tomography (PET/CT) are comparable for the case of cervical cancer. Fifteen cervical cancer patients identified by either a radiation oncologist or an oncologic surgeon had both PET/MR and PET/CT performed for initial staging within 3 weeks. We then compared the results both quantitatively (measuring standardized uptake values [SUVs] on visible lesions) as well as qualitatively (having radiologists and nuclear medicine physicians interprets the results). While interpretations between PET/MR and PET/CT varied in many cases, SUVs of primary lesions were similar to within 25% in all but one case, and correlation coefficient was 0.92. Maximum SUV ranged between 4.9 and 25.2 for PET-MR and between 5.8 and 30.4 for PET-CT for primary tumors and between 1.5 and 18.8 for PET-MR and between 1.8 and 20.8 for PET-CT for nodes. However, clinical reads often varied significantly between PET/MR and PET/CT. This suggests that SUV is similar on PET/MR and PET/CT although the differing anatomic modalities available for correlation may make the difference in terms of qualitative interpretation.

15.
Sci Rep ; 7: 43356, 2017 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-28256615

RESUMO

Studies have shown that tumor angiogenesis is an essential process for tumor growth, proliferation and metastasis. Also, tumor angiogenesis is an important prognostic factor of clear cell renal cell carcinoma (ccRCC), as well as a factor in guiding treatment with antiangiogenic agents. Here, we attempted to find the associations between tumor angiogenesis and radiomic imaging features from PET/MRI. Specifically, sparse canonical correlation analysis was conducted on 3 feature datasets (i.e., radiomic imaging features, tumor microvascular density (MVD), and vascular endothelial growth factor (VEGF) expression) from 9 patients with primary ccRCC. In order to overcome the potential bias of intratumoral heterogeneity of angiogenesis, this study investigated the relationship between regional expressions of angiogenesis and VEGF, and localized radiomic features from different parts within the tumors. Our study highlighted the significant strong correlations between radiomic features and MVD, and also demonstrated that the spatiotemporal features extracted from DCE-MRI provided stronger radiomic correlation to MVD than the textural features extracted from Dixon sequences and FDG PET. Furthermore, PET/MRI, which takes advantage of the combined functional and structural information, had higher radiomics correlation to MVD than solely utilizing PET or MRI alone.


Assuntos
Carcinoma de Células Renais/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias Renais/diagnóstico por imagem , Neovascularização Patológica/diagnóstico por imagem , Fator A de Crescimento do Endotélio Vascular/genética , Adulto , Idoso , Carcinoma de Células Renais/irrigação sanguínea , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Feminino , Expressão Gênica , Humanos , Neoplasias Renais/irrigação sanguínea , Neoplasias Renais/genética , Neoplasias Renais/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Tomografia por Emissão de Pósitrons , Estudo de Prova de Conceito , Estudos Retrospectivos , Carga Tumoral
16.
Front Oncol ; 7: 8, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28168166

RESUMO

INTRODUCTION: Computed tomography (CT), combined positron emitted tomography and CT (PET/CT), and magnetic resonance imaging (MRI) are commonly used in head and neck radiation planning. Hybrid PET/MRI has garnered attention for potential added value in cancer staging and treatment planning. Herein, we compare PET/MRI vs. planning CT for head and neck cancer gross tumor volume (GTV) delineation. MATERIAL AND METHODS: We prospectively enrolled patients with head and neck cancer treated with definitive chemoradiation to 60-70 Gy using IMRT. We performed pretreatment contrast-enhanced planning CT and gadolinium-enhanced PET/MRI. Primary and nodal volumes were delineated on planning CT (GTV-CT) prospectively before treatment and PET/MRI (GTV-PET/MRI) retrospectively after treatment. GTV-PET/MRI was compared to GTV-CT using separate rigid registrations for each tumor volume. The Dice similarity coefficient (DSC) metric evaluating spatial overlap and modified Hausdorff distance (mHD) evaluating mean orthogonal distance difference were calculated. Minimum dose to 95% of GTVs (D95) was compared. RESULTS: Eleven patients were evaluable (10 oropharynx, 1 larynx). Nine patients had evaluable primary tumor GTVs and seven patients had evaluable nodal GTVs. Mean primary GTV-CT and GTV-PET/MRI size were 13.2 and 14.3 cc, with mean intersection 8.7 cc, DSC 0.63, and mHD 1.6 mm. D95 was 65.3 Gy for primary GTV-CT vs. 65.2 Gy for primary GTV-PET/MRI. Mean nodal GTV-CT and GTV-PET/MRI size were 19.0 and 23.0 cc, with mean intersection 14.4 cc, DSC 0.69, and mHD 2.3 mm. D95 was 62.3 Gy for both nodal GTV-CT and GTV-PET/MRI. CONCLUSION: In this series of patients with head and neck (primarily oropharynx) cancer, PET/MRI and CT-GTVs had similar volumes (though there were individual cases with larger differences) with overall small discrepancies in spatial overlap, small mean orthogonal distance differences, and similar radiation doses.

17.
Proc Natl Acad Sci U S A ; 114(3): E426-E435, 2017 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-28053229

RESUMO

Autophagy is a conserved pathway for bulk degradation of cytoplasmic material by a double-membrane structure named the autophagosome. The initiation of autophagosome formation requires the recruitment of autophagy-related protein 9 (ATG9) vesicles to the preautophagosomal structure. However, the functional relationship between ATG9 vesicles and the phagophore is controversial in different systems, and the molecular function of ATG9 remains unknown in plants. Here, we demonstrate that ATG9 is essential for endoplasmic reticulum (ER)-derived autophagosome formation in plants. Through a combination of genetic, in vivo imaging and electron tomography approaches, we show that Arabidopsis ATG9 deficiency leads to a drastic accumulation of autophagosome-related tubular structures in direct membrane continuity with the ER upon autophagic induction. Dynamic analyses demonstrate a transient membrane association between ATG9 vesicles and the autophagosomal membrane during autophagy. Furthermore, trafficking of ATG18a is compromised in atg9 mutants during autophagy by forming extended tubules in a phosphatidylinositol 3-phosphate-dependent manner. Taken together, this study provides evidence for a pivotal role of ATG9 in regulating autophagosome progression from the ER membrane in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Autofagossomos/metabolismo , Proteínas Relacionadas à Autofagia/metabolismo , Retículo Endoplasmático/metabolismo , Proteínas de Membrana/metabolismo , Autofagia/fisiologia , Proteínas de Transporte/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Transporte Proteico/fisiologia
18.
Clin Cancer Res ; 22(12): 2950-9, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-26787754

RESUMO

PURPOSE: Clear cell renal cell carcinoma (ccRCC) has recently been redefined as a highly heterogeneous disease. In addition to genetic heterogeneity, the tumor displays risk variability for developing metastatic disease, therefore underscoring the urgent need for tissue-based prognostic strategies applicable to the clinical setting. We have recently employed the novel PET/magnetic resonance (MR) image modality to enrich our understanding of how tumor heterogeneity can relate to gene expression and tumor biology to assist in defining individualized treatment plans. EXPERIMENTAL DESIGN: ccRCC patients underwent PET/MR imaging, and these images subsequently used to identify areas of varied intensity for sampling. Samples from 8 patients were subjected to histologic, immunohistochemical, and microarray analysis. RESULTS: Tumor subsamples displayed a range of heterogeneity for common features of hypoxia-inducible factor expression and microvessel density, as well as for features closely linked to metabolic processes, such as GLUT1 and FBP1. In addition, gene signatures linked with disease risk (ccA and ccB) also demonstrated variable heterogeneity, with most tumors displaying a dominant panel of features across the sampled regions. Intriguingly, the ccA- and ccB-classified samples corresponded with metabolic features and functional imaging levels. These correlations further linked a variety of metabolic pathways (i.e., the pentose phosphate and mTOR pathways) with the more aggressive, and glucose avid ccB subtype. CONCLUSIONS: Higher tumor dependency on exogenous glucose accompanies the development of features associated with the poor risk ccB subgroup. Linking these panels of features may provide the opportunity to create functional maps to enable enhanced visualization of the heterogeneous biologic processes of an individual's disease. Clin Cancer Res; 22(12); 2950-9. ©2016 AACR.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/patologia , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/genética , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Renais/genética , Análise em Microsséries
19.
J Pathol ; 238(4): 531-42, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26415102

RESUMO

Obese animals and non-alcoholic fatty liver disease (NAFLD) patients exhibit elevated blood alcohol, suggesting potential contributions of alcohol metabolism to the development of NAFLD. Liver gene expression in patients with biopsy-proven mild (N = 40) and severe (N = 32) NAFLD were compared to that in healthy liver donors (N = 7) and alcoholic hepatitis (AH; N = 15) using microarrays. Principal components analyses (PCA) revealed similar gene expression patterns between mild and severe NAFLD which clustered with those of AH but were distinct from those of healthy livers. Differential gene expression between NAFLD and healthy livers was consistent with established NAFLD-associated genes and NAFLD pathophysiology. Alcohol-metabolizing enzymes including ADH, ALDH, CYP2E1, and CAT were up-regulated in NAFLD livers. The expression level of alcohol-metabolizing genes in severe NAFLD was similar to that in AH. The NAFLD gene expression profiles provide new directions for future investigations to identify disease markers and targets for prevention and treatment, as well as to foster our understanding of NAFLD pathogenesis and pathophysiology. Particularly, increased expression of alcohol-metabolizing genes in NAFLD livers supports a role for endogenous alcohol metabolism in NAFLD pathology and provides further support for gut microbiome therapy in NAFLD management. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley © Sons, Ltd.


Assuntos
Álcoois/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Adulto , Biópsia , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Obesidade/genética , Obesidade/metabolismo , Transcriptoma
20.
AJR Am J Roentgenol ; 205(6): 1295-305, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26587937

RESUMO

OBJECTIVE: The objective of our study was to quantitatively compare misregistration in selected abdominopelvic organs between PET/CT acquisitions and simultaneous and sequential PET/MRI acquisitions. SUBJECTS AND METHODS: PET/MR images of 15 healthy volunteers and seven patients with bladder cancer were acquired. Ten clinical PET/CT studies acquired during the same time frame of body mass index-matched control subjects were chosen. PET/MRI and PET/CT registration of selected abdominopelvic organs was measured and compared. RESULTS: The overall mean misregistration with PET/MRI was significantly higher than that with PET/CT (p < 0.001). Sequential PET/MRI acquisition was significantly inferior to PET/CT (p = 0.02), whereas there was no significant difference between simultaneous PET/MRI acquisition and PET/CT (p = 0.38). Simultaneous PET/MRI acquisition was significantly better than sequential PET/MRI acquisition (p < 0.001). The mean misregistration for all organs with the T1-weighted volumetric interpolated breath-hold examination (VIBE) sequence (2.39 cm) was significantly inferior to PET/CT (p < 0.001). Although the T2-weighted HASTE breath-hold sequence was significantly inferior to PET/CT (p = 0.04), the T2 HASTE non-breath-hold sequence and T2 STIR sequence (0.18 cm) were significantly superior to both PET/CT and the T1 VIBE sequence (p < 0.001). Within the same sequence (T1 VIBE breath-hold sequence), the mean misregistrations with sequential and simultaneous PET/MRI acquisitions were both significantly greater than with PET/CT (p < 0.001), whereas simultaneous PET/MRI acquisition was superior to sequential PET/MRI acquisition (p < 0.001). CONCLUSION: In the abdominopelvic organs, sequentially obtained PET/MRI data have significantly higher misregistration than both PET/CT data and simultaneously acquired PET/MRI data. Simultaneously obtained PET/MRI data are statistically noninferior to PET/CT. Nonradial T1 VIBE has the highest misregistration, whereas T2 STIR and T2 HASTE non-breath-hold are significantly better than both PET/CT and T1 VIBE.


Assuntos
Abdome , Imagem Multimodal/métodos , Neoplasias da Bexiga Urinária/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Voluntários Saudáveis , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X
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