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1.
Adv Mater ; : e2411738, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39444021

RESUMO

Recently, YbCd2Sb2-based Zintl compounds have been widely investigated owing to their extraordinary thermoelectric (TE) performance. However, its p orbitals of anions that determined the valence band structure are split due to crystal field splitting that provides a good platform for band manipulation by doping/alloying and, more importantly, the YbCd2Sb2-based device has yet to be reported. In this work, single-phase YbCd1.5Zn0.5Sb2 is successfully obtained through precise chemical composition control. Then, YbMg2Sb2-alloying increases the cationic vacancy defect formation energy and further optimizes carrier concentration. Moreover, the band structure of YbCd1.5Zn0.5Sb2 is subtly manipulated, and the underlying mechanism is experimentally explored. Combined with the reduced lattice thermal conductivity, a high peak ZT value of ∼1.43 at 700 K is obtained for YbCd1.425Zn0.475Mg0.1Sb2. Subsequently, choosing Fe90Sb10 as the diffusion barrier layer and adopting the transient liquid phase bonding technique, for the first time, it is demonstrated that YbCd2Sb2/Mg3(Sb, Bi)2 TE module with an ultrahigh conversion efficiency of ≈9.0% at a heat difference of 430 K. More importantly, this module displays good thermal stability. This work paves the way for YbCd2Sb2 materials and devices in mid-temperature heat recovery.

2.
Medicine (Baltimore) ; 103(16): e37779, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640333

RESUMO

To develop a scheme for distinguishing Kikuchi-Fujimoto disease (KFD) from lymphoma in patients presenting enlarged lymph nodes (LNs) predominantly on the upper side of the diaphragm. From November 2015 to August 2023, 32 KFD patients and 38 lymphoma patients were pathologically confirmed and enrolled in this retrospectively study. Clinical and 18F-fluorodeoxyglucose positron emission tomography (PET)/computed tomography (CT) features were collected. When comparing those PET/CT parameters, we set 5 models with different research objects: (1) all affected LNs; (2) the 5 largest affected LNs in terms of maximum diameter; (3) the 5 largest affected LNs in terms of maximum standard uptake values (SUVmax); (4) the largest affected LNs in terms of maximum diameter; (5) the largest affected LNs in terms of SUVmax. Compared to lymphoma patients, KFD patients were younger; and with higher incidence of fever, arthralgia, abnormal serum white blood cell, lactate dehydrogenase (LDH) and splenomegaly; lower incidence of affected LNs perinodal infiltration, necrosis and conglomeration; more affected LNs in Head and Neck nodes (particularly in level II) and Axillary in KFD (P ˂ .05). PET/CT parameters presented as various difference in each model. Finally, 11 clinical and PET/CT features (age ≤ 34, with fever, arthralgia, abnormal white blood cell, abnormal LDH, and without node necrosis and node conglomeration have a score of 2 each; splenomegaly, perinodal infiltration, median maximum diameter ≤ 20.5 and median SUVmax ≤ 7.1 of affected LNs in model 2 have score of 1 each) were selected as scheme items for distinguishing KFD from lymphoma. Individuals who have a total score > 8, meet the criteria for KFD. Sensitivity and specificity were high: 86.8% (95% CI: 71.9%, 95.5%) and 96.9% (95% CI: 83.7%, 99.5%), AUC = 0.975 (95% CI: 90.5%, 99.6%), respectively. It can effectively distinguish KFD from lymphoma by clinical and PET/CT parameters.


Assuntos
Linfadenite Histiocítica Necrosante , Linfoma , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Linfadenite Histiocítica Necrosante/diagnóstico por imagem , Linfadenite Histiocítica Necrosante/patologia , Estudos Retrospectivos , Esplenomegalia , Linfoma/diagnóstico por imagem , Linfoma/patologia , Fluordesoxiglucose F18 , Artralgia/patologia , Necrose/patologia , Linfonodos/diagnóstico por imagem , Linfonodos/patologia
3.
Science ; 382(6673): 921-928, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37995213

RESUMO

Thermoelectric interface materials (TEiMs) are essential to the development of thermoelectric generators. Common TEiMs use pure metals or binary alloys but have performance stability issues. Conventional selection of TEiMs generally relies on trial-and-error experimentation. We developed a TEiM screening strategy that is based on phase diagram predictions by density functional theory calculations. By combining the phase diagram with electrical resistivity and melting points of potential reaction products, we discovered that the semimetal MgCuSb is a reliable TEiM for high-performance MgAgSb. The MgCuSb/MgAgSb junction exhibits low interfacial contact resistivity (ρc <1 microhm square centimeter) even after annealing at 553 kelvin for 16 days. The fabricated two-pair MgAgSb/Mg3.2Bi1.5Sb0.5 module demonstrated a high conversion efficiency of 9.25% under a 300 kelvin temperature gradient. We performed an international round-robin testing of module performance to confirm the measurement reliability. The strategy can be applied to other thermoelectric materials, filling a vital gap in the development of thermoelectric modules.

4.
ACS Appl Mater Interfaces ; 14(51): 56948-56956, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36520047

RESUMO

It is known that Yb-filled skutterudite with excellent thermoelectric performance is promising for a power generation device in the intermediate temperature region. Here we created a new approach to obtain nanostructured materials by adding Si to Co-overstoichiometric Yb-filled skutterudite through high-energy ball milling, which embedded bottom-up formed CoSi2 nanoparticles into grain-refining Yb0.25Co4Sb12, synergistically resulting in the enhanced thermoelectric properties and room-temperature hardness. On one hand, the abundant grain boundaries and phase interfaces effectively blocked the propagation of medium-low frequency phonons, resulting in a lower lattice thermal conductivity. On the other hand, phase interfaces barrier nicely screened a portion of low-energy electrons, leading to an improved power factor. As a result, an enhanced peak ZT value of ∼1.43 at 823 K and a promising average ZT of ∼1.00 between 300 and 823 K were achieved in the Yb0.25Co4Sb12/0.05CoSi2 sample. Meanwhile, such nanostructures also enhanced the hardness through the collective contributions of second phase and fine grain strengthening, which made skutterudite more competitive in practical application.

5.
Clin Rheumatol ; 41(5): 1543-1550, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35089469

RESUMO

OBJECTIVE: To investigate the value of 68 Ga-PSMA-11 positron emission tomography/computerized tomography (PET/CT) in evaluating lacrimal and salivary glands function. METHODS: Ten patients with pSS and 18 healthy volunteers were recruited in this study. All participants underwent 68 Ga-PSMA-11 PET/CT, and the patients with pSS performed salivary gland scintigraphy the next day. The maximum standardized uptake value (SUVmax), average of the standard uptake value (SUVavg), the average CT value (CTavg), and volume (V) in the region of interest (ROI) of each lacrimal and salivary gland were analyzed in68Ga-PSMA-11 PET/CT. The uptake ratio (UR) of the bilateral parotid gland and submandibular gland was calculated in salivary gland scintigraphy (SGS). Statistical analysis was processed by the SPSS software and the MedCalc software. A p-value of < 0.05 was considered as statistically significant. RESULTS: Almost all the parameters of pSS were significantly lower than those of the control group (p < 0.05). The left parotid gland (PG) UR was positive correlation with left PG SUVmax (r = 0.758, p = 0.011) and left PG SUVavg (r = 0.770, p = 0.009); the right PGUR was positive correlation with right PG SUVmax (r = 0.721, p = 0.019) and right PG SUVavg (r = 0.721, p = 0.019). The SUVmax and SUVavg of both sides of acrimal and salivary glands had area under the receiver operating curve values greater than 0.5. CONCLUSIONS: 68 Ga-PSMA-11 PET/CT can simultaneously enable the visualization of lacrimal glands and salivary glands and be used to evaluate the lacrimal and salivary glands function. Key Points • We have firstly investigated the value of 68 Ga-PSMA-11 PET/CT in evaluating lacrimal and salivary glands function in patients with pSS 68 Ga-PSMA-11 PET/CT can simultaneously allow the visualization of lacrimal glands and salivary glands. • The results of the present study imply that 68 Ga-PSMA-11 PET/CT can be used to evaluate the lacrimal and salivary glands function in patients with pSS meanwhile.


Assuntos
Aparelho Lacrimal , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Aparelho Lacrimal/diagnóstico por imagem , Glândula Parótida/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Cintilografia , Glândulas Salivares/diagnóstico por imagem
6.
Quant Imaging Med Surg ; 11(8): 3619-3628, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34341736

RESUMO

BACKGROUND: This study aimed to assess the value of biphasic GA 68-labeled prostate-specific membrane antigen-11 (68Ga-PSMA-11) positron emission tomography/computed tomography (PET/CT) scan in the differential diagnosis and risk stratification of initial primary prostate cancer (PCa). METHODS: A total of 51 patients with PCa (8 low- and intermediate-risk PCa patients and 43 high-risk PCa patients) and 36 patients with benign prostate lesions, who underwent standard whole-body imaging and delayed pelvic imaging of 68Ga-PSMA-11 PET/CT, were enrolled in this prospective study. The PET parameters, such as maximum and mean standard uptake value (SUVmax and SUVmean), and maximum and mean standard retention index of PET images were calculated and compared in different prostate lesions. The diagnostic performances of the PET parameters were evaluated by receiver operating characteristic (ROC) curves. RESULTS: All the PET parameters of PCa participants were significantly higher than those of participants with benign prostate lesions (P<0.001). The SUVmean of delayed imaging had the best performance in the diagnosis of PCa with an area under the curve (AUC) of 0.918 (95% CI: 0.858 to 0.977), the sensitivity of 90.0%, and specificity of 83.3%. The SUVmax and SUVmean of high-risk PCa participants were significantly higher than those of low- and intermediate-risk PCa participants (P<0.005). The SUVmax of standard imaging had the best performance in predicting high-risk PCa with an AUC of 0.890 (95% CI: 0.799 to 0.980), a sensitivity of 76.7%, and a specificity of 100.0%. CONCLUSIONS: The biphasic 68Ga-PSMA-11 PET/CT scan had good performance in discriminating prostate cancer from benign prostate diseases. The SUVmean of the prostate lesion at delayed imaging of 68Ga-PSMA-11 PET/CT had the best value in the differential diagnosis of PCa, and the SUVmax at standard imaging was most valuable in predicting the risk stratification of PCa.

7.
Nucl Med Commun ; 42(3): 225-233, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33306636

RESUMO

PURPOSE: To compare the diagnostic accuracy of dual-phase 99mTc-MIBI single photon emission computed tomography/computed tomography (SPECT/CT) and 4D CT for the localization of hyperfunctioning parathyroid glands, a systematic review and meta-analysis was performed. Whether 4D CT combined to SPECT/CT [contrast-enhanced (CE)-SPECT/CT] had a better diagnostic performance than SPECT/CT alone in this scenario was also evaluated. MATERIAL AND METHODS: PubMed and Embase databases were searched for eligible studies. To reduce interstudy heterogeneity, only studies with clear head-to-head comparison were included. Publication bias was assessed by the Deeks funnel plot. The pooled sensitivity, specificity and the area under the curve (AUC) for 4D CT, SPECT/CT and CE-SPECT/CT were determined by random-effect analysis, respectively. RESULTS: Nine studies met the inclusion criteria, with a total of 911 participants. The sensitivity and specificity of 4D CT were 0.85 [95% confidence interval (CI), 0.69-0.94] and 0.93 (95% CI, 0.88-0.96), whereas the sensitivity and specificity for SPECT/CT were 0.68 (95% CI, 0.51-0.82; P = 0.048 compared with 4D CT) and 0.98 (95% CI, 0.95-0.99; P = 0.014 compared with 4D CT), respectively. CE-SPECT/CT is comparable to SPECT/CT in specificity and AUC, but it may improve the sensitivity (although there was a lack of statistical difference, 0.87 vs. 0.78; P = 0.125). CONCLUSION: Although 4D CT shows comparable AUC and borderline better sensitivity than SPECT/CT, its clinical application is confined by relatively low specificity and high radiation exposure. CE-SPECT/CT may improve the sensitivity without compromising the specificity and AUC of SPECT/CT.


Assuntos
Tomografia Computadorizada Quadridimensional , Glândulas Paratireoides/diagnóstico por imagem , Glândulas Paratireoides/fisiopatologia , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Tecnécio Tc 99m Sestamibi , Humanos , Sensibilidade e Especificidade
8.
Biochem Genet ; 58(5): 691-704, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32419060

RESUMO

Non-alcoholic fatty liver disease (NAFLD) have a high prevalence in humans in the past two decades. Here, we elucidated the functions of miR-30a-3p in the development of NAFLD and identified its potential targets. HepG-2 cells and NAFLD patients' blood samples were used in our study. Bioinformatics analysis as well as luciferase reporter assays were employed to distinguish peroxisome proliferator-activated receptor alpha (PPAR-α) as a target gene. Western blotting showed the expressions of lipid metabolic proteins and the target gene PPAR-α. Oil red O staining and triglyceride activity tested the fatty deposits after treatment with miR-30a-3p. miR-30a-3p was substantially up-regulated in NAFLD. Bioinformatics analyses showed that PPAR-α was a possible target of miR-30a-3p, linked with signaling pathways in NAFLD. PPAR-α as a novel target of miR-30a-3p, and suppression of its levels. The lipid metabolic-related proteins ACC, p-GSK-3ß and FASN were up-regulated after transfecting with miR-30a-3p mimic, but the proteins CPT1, p-AMPK and UCP2 were down-regulated. miR-30a-3p inhibitor could diminish the protein manifestation of ACC, p-GSK-3ß and FASN; and augment the protein manifestation of CPT1, p-AMPK and UCP2. On the contrary, overexpression of miR-30a-3p had adverse impacts on the performance of hepatocellular lipid accumulation and Triglyceride (TG) activity. Co-treatment with miR-30a-3p mimic and overexpression PPAR-α could revise the hepatic steatosis and the TG level induced by fat milk. Our findings suggest that miR-30a-3p/PPAR-α may be developed as a potential agent in NAFLD, which is enough to attenuate triglyceride accumulation and hepatic steatosis.


Assuntos
MicroRNAs/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , PPAR alfa/metabolismo , Adulto , Estudos de Casos e Controles , Células Hep G2 , Humanos , Metabolismo dos Lipídeos , Fígado/metabolismo , Fígado/patologia , MicroRNAs/sangue
9.
ACS Appl Mater Interfaces ; 12(1): 945-952, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31820912

RESUMO

A tiny amount of Mn is doped in In0.15Sb1.85Te3 sample to tailor its carrier concentration, thus boosting the power factor and suppressing the bipolar effect. Furthermore, large amounts of nanotwins are constructed to effectively scatter the phonons and reduce the lattice thermal conductivity. As a result, the zT value of Mn0.02In0.15Sb1.83Te3 is enhanced up to 1.0 at 673 K, making this material a robust candidate for medium-temperature (500-673 K) thermoelectric applications. Then combining with the low-temperature thermoelectric material Mn0.0075Bi0.5Sb1.4925Te3 previously reported by our group and using nickel as a barrier layer, a high average zT value of 1.08 during a broad temperature range from 303 to 673 K together with an Ohmic contact interface bonding is achieved in the p-type segmented leg fabricated via simple one-step sintering. Finally, the maximum theoretical conversion efficiency with a temperature difference of 370 K reaches ∼12.7%.

10.
J Gynecol Oncol ; 30(6): e89, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31576685

RESUMO

OBJECTIVE: To investigate the prognostic value of metabolic tumor volume (MTV) and total lesion glycolysis (TLG), measured by preoperative ¹8F-fluorodeoxyglucose positron emission tomography/computed tomography (¹8F-FDG PET/CT), in risk stratification of patients with endometrial carcinoma (EC). METHODS: The patients with pathological diagnosis of EC who underwent preoperative ¹8F-FDG PET/CT imaging were retrospectively selected for analysis of the prognostic values of PET parameters in risk classification and lymph node metastases (LNMs). Receiver-operating-characteristic analysis was used to analyze the correlation of PET parameters cutoff values with deep myometrial invasion (MI), lymphovascular space involvement and LNM for prognostic values in risk stratification. RESULTS: The sensitivity, specificity, positive predictive value, negative predictive value and accuracy for detection of LNM are 83.3%, 99.7%, 90.9%, 99.5% and 99.2%, respectively. The MTV and TLG of primary lesion of EC in the patients with LNM are notably higher than those in patients without LNM, p<0.010. The MTV and TLG of the EC primary lesions in high-risk patients are significantly higher than those in low-risk patients (p<0.010), but the maximum standardized uptake value (SUVmax) is not. The MTV and TLG of primary lesions were superior to SUVmax for predicting of deep MI, LNM and high-risk of EC (p<0.005). CONCLUSION: MTV and TLG of primary lesions are more valuable in predicting risk stratification of EC patients. Preoperative ¹8F-FDG PET/CT imaging is useful in predicting the LNM of EC and may help guide pelvic lymphadenectomy to avoid unnecessary pelvic lymphadenectomy in EC patients with low-risk stratification.


Assuntos
Neoplasias do Endométrio/patologia , Fluordesoxiglucose F18/metabolismo , Glicólise , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Medição de Risco/métodos , Carga Tumoral , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Endométrio/diagnóstico por imagem , Neoplasias do Endométrio/metabolismo , Feminino , Humanos , Excisão de Linfonodo/métodos , Metástase Linfática , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Compostos Radiofarmacêuticos/metabolismo , Estudos Retrospectivos
11.
Indian J Med Res ; 149(5): 627-632, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31417030

RESUMO

Background & objectives: The nature of adaptable change of B-cell lymphoma-2 (BCL-2) and/or Bcl2-associated X protein (BAX) gene expression in the human peripheral blood mononuclear cells (PBMCs) irradiated by radioiodine in thyroid diseases therapy is not fully understood. In this study, the alternation of apoptotic gene expression was evaluated while the PBMCs collected from healthy volunteers were irradiated by the radioiodine-131 (131I). Methods: Fasting blood samples were obtained from healthy volunteers. PBMCs from group 0 to 6 were incubated and exposed to different doses of 131I in cell suspension for 6, 12, 24 and 48 h. The apoptosis rates and expression of BCL-2 and BAX genes of PBMCs were examined. Results: The apoptosis rate in the human PBMCs was gradually enhanced after six hour irradiation. The values of BCL-2 and BAX gene expression in groups 1-6 were higher than in group 0 within 6 h of irradiation, and then, these were decreased gradually from 6 to 12 h. BCL: -2 gene expression increased in groups 1-3 after 12 h irradiation, but there was no difference in groups 4-6. The ratio of BCL-2/BAX gene expression among groups 4-6 gradually decreased during the period from 6 to 12 h, and it was significantly lower than in the group 0 at 12, 24 and 48 h. Interpretation & conclusions: The expression of BCL-2 and BAX genes was initially upregulated following irradiation. Later, the balance of BCL-2/BAX genes expression was adjusted, and then, PBMCs underwent apoptosis at higher doses of radiation.


Assuntos
Apoptose/efeitos da radiação , Leucócitos Mononucleares/efeitos da radiação , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteína X Associada a bcl-2/genética , Apoptose/genética , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Radioisótopos do Iodo/efeitos adversos , Leucócitos Mononucleares/metabolismo , Radiação , Doses de Radiação
13.
Cell Physiol Biochem ; 48(3): 1139-1150, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30041193

RESUMO

BACKGROUND/AIMS: Non-coding RNAs (ncRNAs) play vital regulatory roles in many tumors. However, the functional roles of these transcripts responsible for their dysregulation in breast cancer (BC) are not thoroughly understood. METHODS: We examined the expression of microRNA miR-1471 in BC specimens. Online analysis tools predicted that lncRNA LOC101930370 might act as an endogenous 'sponge' by competing for miR-1471 binding targets. Luciferase assays were used to prove the interaction of LOC101930370, miR-1471 and SHH. Edu, wound-healing and transwell assays were used to verify the contribution of miR-1471 and LOC101930370 on MCF-7 cells proliferation and metastasis. Gain and loss of function studies were performed to evaluate the relevance of Hedgehog pathway with LOC101930370/miR-1471 regulating axis in MCF-7 cells. RESULTS: The expression of miR-1471 was markedly downregulated in BC. Inhibition of miR-1471 by LOC101930370 was proved by luciferase assay. Knockdown of LOC101930370 suppressed BC cells progression. MiR-1471 inhibitor resulted in a more aggressive metastasis of MCF-7 cells. Moreover, SHH and Gli-1 expression were significantly suppressed by LOC101930370 knockdown, and upregulated by miR-1471 inhibitor transfection. CONCLUSIONS: Collectively, our study reveals the interaction between LOC101930370 and miR-1471 for the first time. LOC101930370 positively regulates the expression of SHH by sponging miR-1471, which sheds new light on lncRNA-directed diagnostics and therapeutics in BC.


Assuntos
Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Hedgehog/genética , Transdução de Sinais , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Feminino , Técnicas de Silenciamento de Genes , Proteínas Hedgehog/metabolismo , Humanos , Células MCF-7 , Pessoa de Meia-Idade , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Regulação para Cima , Adulto Jovem
14.
Arch Rheumatol ; 32(4): 365-369, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29901029

RESUMO

Immunoglobulin G4-related lung disease (IgG4-RLD) is a disease in which abundant activated IgG4-positive plasma cells and lymphocytes infiltrate lung tissues with high 18F-fluorodeoxyglucose uptake. Although various forms of radiologic features of IgG4-RLD have been reported, cavitating mass is a rare imaging feature and should be differentiated from cancer. Therefore, in this article, we report two cases both with unprovoked cough, bloody sputum and presenting quite similar cavitating lesions with high 18F-fluorodeoxyglucose uptake on positron emission tomography/ computed tomography, one of which diagnosed as IgG4-RLD and the other as lung cancer based on biopsy eventually. The awareness of the imaging features of IgG4-RLD and lung cancer described in the present study may help physicians to distinguish one from the other. IgG4-RLD should be considered in the differential diagnosis of cavitary lung lesions.

15.
Drug Des Devel Ther ; 10: 2323-31, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27486309

RESUMO

BACKGROUND: Estrogen receptors (ERs) are nuclear transcription factors that are involved in the regulation of many complex physiological processes in humans. ERs have been validated as important drug targets for the treatment of various diseases, including breast cancer, ovarian cancer, osteoporosis, and cardiovascular disease. ERs have two subtypes, ER-α and ER-ß. Emerging data suggest that the development of subtype-selective ligands that specifically target ER-ß could be a more optimal approach to elicit beneficial estrogen-like activities and reduce side effects. METHODS: Herein, we focused on ER-ß and developed its in silico quantitative structure-activity relationship models using machine learning (ML) methods. RESULTS: The chemical structures and ER-ß bioactivity data were extracted from public chemogenomics databases. Four types of popular fingerprint generation methods including MACCS fingerprint, PubChem fingerprint, 2D atom pairs, and Chemistry Development Kit extended fingerprint were used as descriptors. Four ML methods including Naïve Bayesian classifier, k-nearest neighbor, random forest, and support vector machine were used to train the models. The range of classification accuracies was 77.10% to 88.34%, and the range of area under the ROC (receiver operating characteristic) curve values was 0.8151 to 0.9475, evaluated by the 5-fold cross-validation. Comparison analysis suggests that both the random forest and the support vector machine are superior for the classification of selective ER-ß agonists. Chemistry Development Kit extended fingerprints and MACCS fingerprint performed better in structural representation between active and inactive agonists. CONCLUSION: These results demonstrate that combining the fingerprint and ML approaches leads to robust ER-ß agonist prediction models, which are potentially applicable to the identification of selective ER-ß agonists.


Assuntos
Bases de Dados Factuais , Descoberta de Drogas/métodos , Receptor beta de Estrogênio/agonistas , Aprendizado de Máquina , Simulação por Computador , Humanos , Publicação de Acesso Aberto , Relação Quantitativa Estrutura-Atividade
16.
Clin Physiol Funct Imaging ; 36(2): 118-25, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25412856

RESUMO

BACKGROUND AND AIM: The estimation of the glomerular filtration rate (GFR) is essential for the renal function. However, all estimation methods for GFR have advantages and disadvantages. The aim of this study was to develop a new quantitative method for estimating GFR and evaluate its clinical value. METHODS: The new GFR was estimated by quantifying the accumulation of Tc-99m DTPA in the dual kidneys and bladder during a gamma camera renogram study in 116 patients with chronic kidney disease. GFR was determined by this new method (nGFR), Gates' gamma camera technique (gGFR), a two-plasma sampling method (tGFR) and creatinine-based clearance as estimated by Cockcroft-Gault (cGFR) and abbreviated MDRD (aGFR) formulae. The correlation analysis, Bland-Altman analysis and receiver-operating characteristic (ROC) plots were carried out among above methods. RESULTS: The nGFR value has significant correlation with tGRF (r = 0·827, P<0·01). The nGFR had the best overall performances with a lowest bias deviation (3·1 ml min(-1) /1·73 m(2) ), better precision (53·0 ml min(-1) /1·73 m(2) ), narrowest interquartile range (13·5 ml min(-1) /1·73 m(2) ) and best accuracy (68·1%) within 30% of the tGFR, compared with those of gGFR, cGFR and aGFR. The new method had the similar maximum accuracy with the Gates' method and creatinine clearance as estimated by Cockcroft-Gault and abbreviated modification of diet in renal disease (MDRD) method. The new method had better repeatability characteristic compared with the Gates' method. CONCLUSIONS: The new method for estimating GFR had the better performances compared with the Gates' method and creatinine clearance as estimated by Cockcroft-Gault and MDRD method.


Assuntos
Taxa de Filtração Glomerular , Rim/diagnóstico por imagem , Renografia por Radioisótopo/métodos , Compostos Radiofarmacêuticos/administração & dosagem , Pentetato de Tecnécio Tc 99m/administração & dosagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Creatinina/sangue , Feminino , Câmaras gama , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Valor Preditivo dos Testes , Renografia por Radioisótopo/instrumentação , Reprodutibilidade dos Testes , Adulto Jovem
17.
Nucl Med Commun ; 35(5): 466-71, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24535381

RESUMO

OBJECTIVE: The aim of this study was to investigate the relationship between mediastinal lymph node metastasis based on fluorine-18 fluorodeoxyglucose ((18)F-FDG) PET/computed tomography (PET/CT) of the primary tumor and various clinical indexes to determine the risk factors for malignant lymph nodes in non-small-cell lung cancer (NSCLC). MATERIALS AND METHODS: A total of 130 patients with histologically proven NSCLC who had not received any therapy underwent (18)F-FDG PET/CT for staging. The relationship between node metastasis, sex, age, smoking status, primary tumor maximum standardized uptake value (SUV(max)), size, pathological type, and differentiation was studied by univariate analyses, and risk factors for nodal metastasis in NSCLC were assessed by multivariate logistic regression. RESULTS: Of the 130 patients, 68 were seen to have nodal metastasis on histological analysis. Nodal metastasis was correlated with SUV(max), size, and differentiation of primary lung lesions (P<0.05), and all the other factors were nonsignificant (P>0.05). On multivariate logistic regression analysis, the only independent factor was SUV(max) of the primary tumor, and the optimal cutoff value was 9.3 (sensitivity: 75.41%, 95% confidence interval: 62.7-85.5; specificity: 54.41%, 95% confidence interval: 41.9-66.5). CONCLUSION: The mediastinal lymph node metastasis ratio was correlated with SUV(max), size, and differentiation in primary lung lesions. SUV(max) was the only independent predictor of lymph node metastasis in NSCLC. Video Abstract: http://links.lww.com/NMC/A22.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Fluordesoxiglucose F18 , Neoplasias Pulmonares/patologia , Mediastino , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Adulto , Idoso , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
18.
Dev Neuropsychol ; 39(1): 37-50, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24405183

RESUMO

Previous research characterizes obsessive compulsive disorder (OCD) as a complex neurobehavioral disorder that may have multiple etiologies ( den Braber et al., 2008 ). This study analyzed neurocognitive function and change in regional cerebral blood flow (rCBF) to characterize OCD. Neurocognitive function and rCBF were examined in medically naïve patients with OCD and contrasted with controls. Results of this study indicated that the neurocognitive functions impaired in OCD are memory, attention, and executive function, which are primarily associated with the frontal and occipital lobes. Dysfunction in the basal ganglia and occipital lobes were associated with OCD and may be an etiological factor in the disorder.


Assuntos
Córtex Cerebral/irrigação sanguínea , Circulação Cerebrovascular/fisiologia , Transtornos Cognitivos/fisiopatologia , Transtorno Obsessivo-Compulsivo/fisiopatologia , Adulto , Atenção/fisiologia , Córtex Cerebral/fisiologia , Transtornos Cognitivos/patologia , Eletroencefalografia , Função Executiva/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória/fisiologia , Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/psicologia , Escalas de Graduação Psiquiátrica , Cintilografia , Tomografia Computadorizada por Raios X
19.
Clin Nucl Med ; 38(11): 874-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24089063

RESUMO

PURPOSE OF THE REPORT: The aim of this study is to observe the abnormalities of regional cerebral blood flow (rCBF) in migraine patients and to evaluate its relation to the severity of the headache in patients with migraine. PATIENTS AND METHODS: The rCBF imaging was done on 19 patients with migraine and 15 normal controls using single-photon emission computed tomography (SPECT). The abnormal character of cerebral perfusion function was analyzed with Statistical Parametric Mapping (SPM) software, and the headache grade of patients was evaluated with the headache severity measuring scale. RESULTS: The results of SPM analysis demonstrated a decreased rCBF on both sides of the frontal and temporal lobes, left parietal lobe, and right occipital lobe (P < 0.001), and increased rCBF focus on the left prefrontal lobe and right temporal lobe (P < 0.001). The headache scores in migraineurs were correlated to the rCBF on the bilateral temporal lobes and right frontal lobe (P < 0.001). CONCLUSIONS: The migraineurs had lower rCBF at the frontal and temporal lobes, and the lower rCBF was correlated to the degree of headache.


Assuntos
Encéfalo/irrigação sanguínea , Encéfalo/fisiopatologia , Circulação Cerebrovascular/fisiologia , Cefaleia/fisiopatologia , Transtornos de Enxaqueca/fisiopatologia , Fluxo Sanguíneo Regional/fisiologia , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Cefaleia/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Transtornos de Enxaqueca/diagnóstico por imagem , Cintilografia
20.
Cancer Biother Radiopharm ; 28(3): 226-32, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23573955

RESUMO

To obtain the characteristic variation of structure and functional groups of α-fetoprotein (AFP) DNA irradiated by iodine-125((125)I), the AFP antisense oligonucleotide labeled with various radioactivity dose (125)I was mixed with the AFP DNA in a simulated polymerase chain reaction temperature condition. After the mixtures were irradiated by the (125)I from 2 to 72 hours, the mutation of the biogenic conformation and functional groups of the irradiated DNA were investigated using laser Raman spectroscopy. The shifted peak and the decreased intensity of the characteristic Raman spectra were found, which demonstrated that the structure of the phosphodiester linkage was broke, the pyridine and purine bases in DNA emerged and damaged. The model of gene conformation changed from form B to form C spectrum after the nanometer-range irradiation with (125)I from 2 to 24 hours. The damage of local pyridine and purine bases gradually increased along with the accumulation of irradiation, and the bases and ribosome were finally dissociated and stacked.


Assuntos
Dano ao DNA , DNA/química , Radioisótopos do Iodo/química , alfa-Fetoproteínas/química , alfa-Fetoproteínas/genética , DNA/efeitos da radiação , Terapia Genética/métodos , Humanos , Oligonucleotídeos Antissenso/química , Oligonucleotídeos Antissenso/genética , Radioterapia/métodos , Análise Espectral Raman
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