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1.
Neurobiol Dis ; 197: 106527, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38740347

RESUMEN

BACKGROUND: Neurotransmitter deficits and spatial associations among neurotransmitter distribution, brain activity, and clinical features in Parkinson's disease (PD) remain unclear. Better understanding of neurotransmitter impairments in PD may provide potential therapeutic targets. Therefore, we aimed to investigate the spatial relationship between PD-related patterns and neurotransmitter deficits. METHODS: We included 59 patients with PD and 41 age- and sex-matched healthy controls (HCs). The voxel-wise mean amplitude of the low-frequency fluctuation (mALFF) was calculated and compared between the two groups. The JuSpace toolbox was used to test whether spatial patterns of mALFF alterations in patients with PD were associated with specific neurotransmitter receptor/transporter densities. RESULTS: Compared to HCs, patients with PD showed reduced mALFF in the sensorimotor- and visual-related regions. In addition, mALFF alteration patterns were significantly associated with the spatial distribution of the serotonergic, dopaminergic, noradrenergic, glutamatergic, cannabinoid, and acetylcholinergic neurotransmitter systems (p < 0.05, false discovery rate-corrected). CONCLUSIONS: Our results revealed abnormal brain activity patterns and specific neurotransmitter deficits in patients with PD, which may provide new insights into the mechanisms and potential targets for pharmacotherapy.


Asunto(s)
Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/fisiopatología , Masculino , Femenino , Persona de Mediana Edad , Anciano , Encéfalo/metabolismo , Imagen por Resonancia Magnética/métodos , Neurotransmisores/metabolismo , Imagen Multimodal/métodos
2.
Cereb Cortex ; 33(9): 5501-5506, 2023 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-36635220

RESUMEN

Vascular mild cognitive impairment (VMCI) is an early and reversible stage of dementia. Volume differences in regional gray matter may reveal the development and prognosis of VMCI. This study selected 2 of the most common types of VMCI, namely, periventricular white matter hyperintensities (PWMH, n = 14) and strategic single infarctions (SSI, n = 10), and used the voxel-based morphometry method to quantify their morphological characteristics. Meanwhile, age- and sex-matched healthy volunteers were included (n = 16). All the participants were neuropsychologically tested to characterize their cognitive function and underwent whole-brain magnetic resonance imaging scanning. Our results showed that the volumes of the bilateral temporal lobes and bilateral frontal gray matter were obviously diminished in the PWMH group. The atrophy volume difference was 4,086 voxels in the left temporal lobe, 4,154 voxels in the right temporal lobe, 1,718 voxels in the left frontal lobe, and 1,141 voxels in the right frontal lobe (P ≤ 0.001). Moreover, the characteristics of the gray matter atrophy associated with the PWMH were more similar to those associated with Alzheimer's disease than SSI, which further revealed the susceptibility for escalation from PWMH to dementia. In conclusion, PWMH patients and SSI patients have different morphological characteristics, which explain the different prognoses of VMCI.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Pruebas Neuropsicológicas , Disfunción Cognitiva/patología , Encéfalo , Sustancia Gris/patología , Enfermedad de Alzheimer/patología , Imagen por Resonancia Magnética , Atrofia/patología , Diagnóstico Precoz
3.
NMR Biomed ; : e4940, 2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-36978258

RESUMEN

The insufficiently long RF saturation duration and relaxation delay in chemical exchange saturation transfer (CEST)-MRI experiments may result in underestimation of CEST measurements. To maintain the CEST effect without prolonging the saturation duration and reach quasi-steady state (QUASS), a deep learning method was developed to reconstruct a QUASS CEST image pixel by pixel from non-steady-state CEST acquired in experiments. In this work, we established a tumor-bearing rat model on a 7 T horizontal bore small-animal MRI scanner, allowing ground-truth generation, after which a bidirectional long short-term memory network was formulated and trained on simulated CEST Z-spectra to reconstruct the QUASS CEST; finally, the ground truth yielded by experiments was used to evaluate the performance of the reconstruction model by comparing the estimates with the ground truth. For quantitation evaluation, linear regression analysis, structural similarity index (SSIM) and peak signal-to-noise ratio (peak SNR) were used to assess the proposed model in the QUASS CEST reconstruction. In the linear regression analysis of in vivo data, the coefficient of determination for six different representative frequency offsets was at least R2 = 0.9521. Using the SSIM and peak SNR as evaluation metrics, the reconstruction accuracies of in vivo QUASS CEST were found to be 0.9991 and 46.7076, respectively. Experimental results demonstrate that the proposed model provides a robust and accurate solution for QUASS CEST reconstruction using a deep learning mechanism.

4.
J Magn Reson Imaging ; 2023 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-38006286

RESUMEN

BACKGROUND: Previous studies have used different imaging sequences and different enhanced phases for breast lesion calsification in radiomics. The optimal sequence and contrast enhanced phase is unclear. PURPOSE: To identify the optimal magnetic resonance imaging (MRI) radiomics model for lesion clarification, and to simulate its incremental value for multiparametric MRI (mpMRI)-guided biopsy. STUDY TYPE: Retrospective. POPULATION: 329 female patients (138 malignant, 191 benign), divided into a training set (first site, n = 192) and an independent test set (second site, n = 137). FIELD STRENGTH/SEQUENCE: 3.0-T, fast spoiled gradient-echo and fast spin-echo T1-weighted imaging (T1WI), fast spin-echo T2-weighted imaging (T2WI), echo-planar diffusion-weighted imaging (DWI), and fast spoiled gradient-echo contrast-enhanced MRI (CE-MRI). ASSESSMENT: Two breast radiologists with 3 and 10 years' experience developed radiomics model on CE-MRI, CE-MRI + DWI, CE-MRI + DWI + T2WI, CE-MRI + DWI + T2WI + T1WI at each individual phase (P) and for multiple combinations of phases. The optimal radiomics model (Rad-score) was identified as having the highest area under the receiver operating characteristic curve (AUC) in the test set. Specificity was compared between a traditional mpMRI model and an integrated model (mpMRI + Rad-score) at sensitivity >98%. STATISTICAL TESTS: Wilcoxon paired-samples signed rank test, Delong test, McNemar test. Significance level was 0.05 and Bonferroni method was used for multiple comparisons (P = 0.007, 0.05/7). RESULTS: For radiomics models, CE-MRI/P3 + DWI + T2WI achieved the highest performance in the test set (AUC = 0.888, 95% confidence interval: 0.833-0.944). The integrated model had significantly higher specificity (55.3%) than the mpMRI model (31.6%) in the test set with a sensitivity of 98.4%. DATA CONCLUSION: The CE-MRI/P3 + DWI + T2WI model is the optimized choice for breast lesion classification in radiomics, and has potential to reduce benign biopsies (100%-specificity) from 68.4% to 44.7% while retaining sensitivity >98%. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

5.
BMC Med Imaging ; 23(1): 185, 2023 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-37964218

RESUMEN

BACKGROUND: 1H magnetic resonance spectroscopy (1H-MRS) can be used to study neurological disorders because it can be utilized to examine the concentrations of related metabolites. However, the diagnostic utility of different field strengths for temporal lobe epilepsy (TLE) remains unclear. The purpose of this study is to make quantitative comparisons of metabolites of TLE at 1.5T and 3.0T and evaluate their efficacy. METHODS: Our retrospective collections included the single-voxel 1H-MRS of 23 TLE patients and 17 healthy control volunteers (HCs) with a 1.5T scanner, as well as 29 TLE patients and 17 HCs with a 3.0T scanner. Particularly, HCs were involved both the scans with 1.5T and 3.0T scanners, respectively. The metabolites, including the N-acetylaspartate (NAA), creatine (Cr), and choline (Cho), were measured in the left or right temporal pole of brain. To analyze the ratio of brain metabolites, including NAA/Cr, NAA/Cho, NAA/(Cho + Cr) and Cho/Cr, four controlled experiments were designed to evaluate the diagnostic utility of TLE on 1.5T and 3.0T MRS, included: (1) 1.5T TLE group vs. 1.5T HCs by the Mann-Whitney U Test, (2) 3.0T TLE group vs. 3.0T HCs by the Mann-Whitney U Test, (3) the power analysis for the 1.5T and 3.0T scanner, and (4) 3.0T HCs vs. 1.5T HCs by Paired T-Test. RESULTS: Three metabolite ratios (NAA/Cr, NAA/Cho, and NAA/(Cho + Cr) showed the same statistical difference (p < 0.05) in distinguishing the TLE from HCs in the bilateral temporal poles when using 1.5T or 3.0T scanners. Similarly, the power analysis demonstrated that four metabolite ratios (NAA/Cr, NAA/Cho, NAA/(Cho + Cr), Cho/Cr) had similar distinction abilities between 1.5T and 3.0T scanner, denoting both 1.5T and 3.0T scanners were provided with similar sensitivities and reproducibilities for metabolites detection. Moreover, the metabolite ratios of the same healthy volunteers were not statistically different between 1.5T and 3.0T scanners, except for NAA/Cho (p < 0.05). CONCLUSIONS: 1.5T and 3.0T scanners may have comparable diagnostic potential when 1H-MRS was used to diagnose patients with TLE.


Asunto(s)
Epilepsia del Lóbulo Temporal , Humanos , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/metabolismo , Imagen por Resonancia Magnética , Estudios Retrospectivos , Espectroscopía de Resonancia Magnética/métodos , Lóbulo Temporal/metabolismo , Creatina/metabolismo , Colina
6.
Eur Radiol ; 31(5): 3347-3354, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33185752

RESUMEN

OBJECTIVES: To evaluate the diagnostic value and reproducibility of T2 mapping versus apparent diffusion coefficients (ADC) for identifying malignant lymph nodes in patients with non-mucinous rectal adenocarcinoma. METHODS: High-resolution magnetic resonance imaging, diffusion-weighted imaging, and T2 mapping were performed on patients with suspected metastatic lymph nodes in the mesorectum or around the superior rectal artery with a short-axis diameter of 4-10 mm. The T2 and ADC values of pathology-confirmed metastatic versus non-metastatic lymph nodes were compared using the independent-samples t test and receiver operating characteristic curves. Intra- and inter-observer reproducibility were tested. The cutoff value for T2 relaxation time was determined. RESULTS: In total, 67 lymph nodes underwent histological analysis, with 24 in the non-metastatic and 43 in the metastatic groups. Intra- and inter-observer agreements for T2 values were 0.999 and 0.998, respectively, which were higher than the ADC values of 0.924 and 0.844, respectively. The mean T2 and ADC values for metastatic lymph nodes (65 ± 7.8 ms and 1.17 ± 0.16 × 10-3 mm2/s, respectively) were significantly lower than for benign lymph nodes(83 ± 5.7 ms and 1.29 ± 0.15 × 10-3 mm2/s, respectively). T2 values had a higher AUC value of 0.990 than the AUC value for ADC of 0.729. With a cutoff value of 77 ms, sensitivity and specificity for T2 values were 95% and 96%, respectively. CONCLUSIONS: T2 mapping had higher diagnostic efficacy and reproducibility than ADC and may be useful in differentiating metastatic from non-metastatic lymph nodes in rectal cancer. KEY POINTS: • Mean T2 values were significantly shorter for malignant versus benign LNs in patients with non-mucinous rectal adenocarcinoma. • The diagnostic efficacy and reproducibility of T2 values were excellent and superior to ADC values.


Asunto(s)
Ganglios Linfáticos , Neoplasias del Recto , Imagen de Difusión por Resonancia Magnética , Estudios de Factibilidad , Humanos , Ganglios Linfáticos/diagnóstico por imagen , Metástasis Linfática/diagnóstico por imagen , Curva ROC , Neoplasias del Recto/diagnóstico por imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
7.
Inorg Chem ; 60(18): 14286-14293, 2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34503326

RESUMEN

Stimuli-responsive functional materials, especially the light stimulation color change and tunable fluorescent materials, have received considerable attention because of their broad applications in smart materials. Herein, a series of lanthanide-based [Ln = Nd(III) (1), Sm(III) (2), Eu(III) (3), Gd(III) (4), Tb(III) (5), Yb(III) (6), and Lu(III) (7)] crystalline complexes were attained by simply adding the aqueous lanthanide nitrate solution to the water-soluble naphthalenediimide derivative. The obtained lanthanide-based crystalline materials not only show significant photochromism but also possess reactive organic radicals under ambient conditions. Intriguingly, photoswitchable near-infrared (NIR) fluorescence was realized in the crystalline complex 1. The structures of these crystalline materials were systematically studied to clarify the weak interaction-assisted charge-transfer process. The underlying multiple-interaction-assisted supramolecular self-assembly, the radical-doped nature, and the corresponding photochromic mechanism were thoroughly unearthed by single-crystal X-ray diffraction, in situ solid-state UV-vis diffuse reflectance, and electron paramagnetic resonance spectrometric analysis.

8.
BMC Med Imaging ; 20(1): 4, 2020 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-31931731

RESUMEN

BACKGROUND: Lung cancer brain metastases are very common and one of the common causes of treatment failure. We aimed to examine the clinical use of chemical exchange saturation transfer (CEST) technology in the evaluation of brain metastases for lung cancer diagnosis and prognosis. METHODS: We included26 cases of lung cancer brain metastases, 15 cases of gliomas, and 20 cases with normal tests. The magnetization transfer ratio (MTR;3.5 ppm) image from the GRE-EPI-CEST sequence was analyzed using the ASSET technique and APT technology. The MTR values were measured in the lesion-parenchymal, edema, and non-focus regions, and the MTR image was compared with the conventional MRI. ANOVA and t-test were used for statistical analysis. RESULTS: The lesion-parenchymal, edema, and non-focus areas in the metastatic-tumor-group were red-yellow, yellow-green, and green-blue, and the MTR values were 3.29 ± 1.14%,1.28 ± 0.36%,and 1.26 ± 0.31%, respectively. However, in the glioma-group, the corresponding areas were red, red-yellow, and green-blue, and the MTR values were 6.29 ± 1.58%, 2.87 ± 0.65%, and 1.03 ± 0.30%, respectively. The MTR values of the corresponding areas in the normal-group were 1.07 ± 0.22%,1.04 ± 0.23%, and 1.06 ± 0.24%, respectively. Traditional MR images are in black-white contrast and no metabolic information is displayed. The MTRvalues of the three regions were significantly different among the three groups. The values were also significantly different between the parenchymal and edema areas in the metastatic-tumor-group. There were significant differences in the MTR values between the non-lesion and edema regions, but there was no significant difference between the edema and non-focus areas. In the glioma-group, there were significant differences in the MTR values between the parenchymal and edema areas, between the parenchymal and non-focus areas, and between the edema and non-focus areas. CONCLUSIONS: CEST reflects the protein metabolism; therefore, early diagnosis of brain metastases and assessment of the prognosis can be achieved using molecular imaging.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/secundario , Glioma/diagnóstico por imagen , Glioma/secundario , Neoplasias Pulmonares/diagnóstico por imagen , Adulto , Anciano , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Interpretación de Imagen Radiográfica Asistida por Computador
9.
Eur Radiol ; 29(7): 3441-3449, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31041564

RESUMEN

PURPOSE: The clinical and imaging characteristics of fibromas of the tendon sheath (FTS) closely resemble those of giant cell tumors of the tendon sheath (GCTTS). We aimed to study MRI features of FTS and GCTTS to distinguish the two entities and improve their differential diagnosis. MATERIALS AND METHODS: We retrospectively analyzed data from 18 patients (9 men, 9 women; age, 17-62 years) and 24 patients (13 men, 11 women; age, 15-67 years) treated between May 2011 and May 2016, with histologically confirmed FTS and GCTTS, respectively. Specific MRI features of the two groups were compared using the independent sample t tests and chi-square tests. RESULTS: FTS exhibited round or oval shapes. Proton-weighted images (PDWI) showed heterogeneous hypointensity that appeared striped or disordered and was located in the lesion center. Enhanced scans demonstrated asymmetrical signal in the foci. GCTTS mostly exhibited a lobulated or casting mold pattern, with a hypointense ring on PDWI. The hypointense components appeared granular/flaky or separated, sometimes behaving as a uniform signal on PDWI. Significant differences in the following features were observed between the two groups: lesion morphology (p < 0.001); imaging features on PDWI, including whether the signal is homogeneous (p < 0.001); the presence of a hypointense ring (p = 0.006); the location and morphology of hypointensity (p < 0.001); bone absorption (p = 0.008); enhancing pattern (p = 0.008); and whether the tumor crossed the joint (p = 0.026). CONCLUSIONS: FTS and GCTTS demonstrate distinctive MRI features, which can be used for differential diagnosis with sensitivities, specificities, and diagnostic accuracies of 83-100%, 29-79%, and 60-89%, respectively. KEY POINTS: • Fibromas and giant cell tumors of the tendon sheath have distinct features on MRI, including differences in lesion morphology and intensity patterns, which can be used for differential diagnosis. • Among other signs, GCTTS are more uniform than FTS, and FTS have a striped or disordered pattern. • Tumors were classified with 90% accuracy into either FTS or GCTTS based on a combination of two features: homogenous signal and hypointensity shape on PDWI.


Asunto(s)
Fibroma/diagnóstico , Tumor de Células Gigantes de las Vainas Tendinosas/diagnóstico , Imagen por Resonancia Magnética/métodos , Tendones/diagnóstico por imagen , Adolescente , Adulto , Anciano , Biopsia , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
10.
Biotechnol Appl Biochem ; 66(3): 298-308, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30620086

RESUMEN

Gibberellins (GAs) is one kind of important endogenous hormone in plants that regulates vegetative and reproductive growth of plants. GA2ox is a class of oxidase that plays a regulatory role in the third stage of GAs synthesis. In this paper, we cloned the GhGA2ox1 gene from an upland cotton (Gossypium hirsutum L. var. CCRI49). The results showed that the CDS of GhGA2ox1 is 996 bp, which encode 331 amino acids, which has high homology with GhGA2ox2 and NtGA2ox1. The quantitative real-time PCR showed that under the conditions of salt and drought stress, the expression of GhGA2ox1 had a higher upregulation in root, stem, and leaf of transgenic plant, compared with non-transgenic plant. Cotton plant that overexpressed the GhGA2ox1 gene showed higher drought and salt tolerance than non-transgenic cotton plant, and these results were supported by data of higher free proline, chlorophyll, and relative water content in transgenic plant compared with control plant. The expression level of antiretroviral genes, including GhEREB2, GhDREB1, GhWRKY5, and GhP5CS, was upregulated to varying degrees in transgenic plant. The above results indicate that overexpressed GhGA2ox1 gene can increases the tolerance to respond to drought and salt stress in upland cotton.


Asunto(s)
Sequías , Giberelinas/biosíntesis , Gossypium/enzimología , Gossypium/genética , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Estrés Salino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas/genética , Oxidorreductasas/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa
11.
Chem Pharm Bull (Tokyo) ; 67(3): 258-264, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30828002

RESUMEN

A number of clinical trials demonstrated that tigecycline was effective and well tolerated in the treatment of patients with various bacterial infections, but few literatures had shown the coagulopathy induced by tigecycline. To address this concern, we performed a retrospective analysis to assess the impact of tigecycline treatment on coagulation parameters in 50 patients with bacterial infections in our hospital (Shandong Provincial Hospital, China). These patients were treated with tigecycline at Shandong Provincial Hospital in 2015-2016 at either a recommended (50 mg q12h) or a higher dose (100 mg q12h). Coagulation parameters, including Fibrinogen (FIB) levels, prothrombin time (PT), activated partial thromboplastin time (aPTT), platelet count (PLT) and D-dimer, were evaluated in order to assess the impact of tigecycline treatment in these severely infected patients. What we found was that the plasma fibrinogen (FIB) level was 4.63 ± 1.56 g/L before tigecycline treatment, and decreased to 2.92 ± 1.23 g/L during treatment, which was statistically significant (p < 0.001). The mean values of aPTT and PT were significantly increased from 39.58 ± 8.72 to 44.05 ± 10.45 s (p = 0.002), and from 15.37 ± 1.53 to 16.37 ± 2.64 s (p = 0.004), respectively. This study demonstrates that treatment of tigecycline could reduce FIB, prolong aPTT and PT. In conclusion, we advise that it is necessary for practitioners routinely monitor coagulation level in at-rick patient populations treated with tigecycline.


Asunto(s)
Antibacterianos/farmacología , Coagulación Sanguínea/efectos de los fármacos , Tigeciclina/farmacología , Adulto , Anciano , Infecciones Bacterianas/sangre , Infecciones Bacterianas/tratamiento farmacológico , Pruebas de Coagulación Sanguínea , Femenino , Humanos , Riñón/efectos de los fármacos , Riñón/fisiopatología , Hígado/efectos de los fármacos , Hígado/fisiopatología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tigeciclina/uso terapéutico
12.
J Xray Sci Technol ; 27(3): 443-451, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30856155

RESUMEN

PURPOSE: To investigate associations between the clinicopathologic features and CT perfusion parameters of triple-negative breast cancer (TNBC) and non-TNBC using low-dose computed tomography perfusion imaging (LDCTPI), and to find potential clinical applications in the prognosis assessment of TNBC. MATERIALS AND METHODS: A total of 60 patients with breast cancer confirmed by pathological examination were studied prospectively using LDCTPI on a 64-slice spiral CT scanner. The acquired volume data were used for calculations, mapping, and analysis by using a tumor perfusion protocol in the CT perfusion software package to measure 2 parameters namely, blood flow (BF), and permeability surface (PS) area product. Patients were grouped into TNBC (n = 27) and non-TNBC (n = 33) subtypes. Associations between these two subtypes and clinicopathologic characteristics were evaluated by both univariate and multivariate logistic regression. CT perfusion parameters values were compared for clinicopathologic characteristics using independent 2-sample t test. RESULTS: TNBC displayed higher CT perfusion parameters values (BF: 57.56±10.94 vs 52.70±7.79 mL/100 g/min, p = 0.006; PS: 38.98±9.46 vs 33.39±8.07 mL/100 g/min, p = 0.001) than non-TNBC. In addition, breast cancer with poorly histologic grade or positive Ki-67 expression showed higher BF and PS values than those with well and moderately histologic grade or negative Ki-67 expression (p < 0.05). TNBC had poorer histologic grade (P = 0.032) and higher Ki-67 expression (P = 0.013) than non-TNBC. CONCLUSION: LDCTPI is a functional imaging technology from the perspective of hemodynamics with potential of clinical applications. The BF and PS values were higher in TNBC patient group than non-TNBC group. TNBC patients also have poorer clinicopathologic outcome.


Asunto(s)
Imagen de Perfusión/métodos , Tomografía Computarizada Espiral/métodos , Neoplasias de la Mama Triple Negativas/diagnóstico por imagen , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Proyectos Piloto , Pronóstico , Interpretación de Imagen Radiográfica Asistida por Computador , Programas Informáticos , Neoplasias de la Mama Triple Negativas/irrigación sanguínea , Neoplasias de la Mama Triple Negativas/patología
13.
Gastric Cancer ; 21(3): 413-420, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-28871423

RESUMEN

BACKGROUND: This study used low-dose computed tomography (CT) perfusion imaging technology to evaluate the efficacy of neoadjuvant chemotherapy in patients with advanced gastric adenocarcinoma and to determine whether any of the perfusion parameters could predict tumor response to chemotherapy. METHODS: Forty patients with gastric adenocarcinoma (T3-4NxM0) received three cycles of neoadjuvant chemotherapy and low-dose spiral CT perfusion imaging prior to and after the first and third series of chemotherapy. We calculated tissue blood flow (BF) and blood volume (BV) using commercial software. One-way analysis of variance (ANOVA) was used to detect any significant variation of the tested parameters between different times of scanning. Spearman's test was used to evaluate the correlation among perfusion parameters, tumor size and pathological efficacy grade, and clinical response after chemotherapy, respectively. A receiver-operating characteristic analysis was used to determine the optimal diagnostic cutoff value for changes in perfusion parameters and tumor size. RESULTS: One-way ANOVA showed significant differences in BF and BV values between those before and after chemotherapy (p < 0.01). The BF, BV and size reduction rate after three series of chemotherapy were significantly correlated with pathological efficacy grade. BF and BV values after the first and third series of chemotherapy were also significantly correlated with clinical response (p < 0.01, respectively). The diagnostic sensitivity and specificity of the BV reduction rate were higher than those of size reduction rate. CONCLUSIONS: Low-dose CT perfusion imaging is a valuable tool that permits microcirculation evaluation and therefore can evaluate the efficacy of neoadjuvant chemotherapy in patients with advanced gastric adenocarcinoma.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/tratamiento farmacológico , Quimioterapia Adyuvante/métodos , Imagen de Perfusión/métodos , Neoplasias Gástricas/diagnóstico por imagen , Neoplasias Gástricas/tratamiento farmacológico , Adulto , Anciano , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante/métodos , Curva ROC , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
14.
J Xray Sci Technol ; 25(6): 981-991, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28697579

RESUMEN

PURPOSE: To explore the value of low-dose CT perfusion imaging (LDCTPI) technology and its perfusion parameters in assessing response of neoadjuvant chemotherapy (NAC) in patients with advanced gastric cancer (AGC). METHODS: Thirty patients with AGC were studied prospectively by LDCTPI to measure two parameters including blood flow (BF) and blood volume (BV) of tumor area before and after chemotherapy, respectively. All of the patients received two courses of NAC and surgical resection of gastric tumor within one week after chemotherapy, and then obtained the result of postoperative pathology response for chemotherapy. The comparisons of BF and BV values of AGC before and after chemotherapy were analyzed by paired-samples t-test, respectively; and the correlations between BF as well as BV decrease rates after NAC and the pathology response grade were analyzed by Spearman statistical test. Thirty patients were divided into effective and ineffective groups according to different pathology response grade. Comparisons of BF as well as BV decrease rates between effective and ineffective groups were analyzed by independent-samples t-test, respectively. Receiver operating characteristic (ROC) curves were used to determine the cutoff values of BF and BV decrease rates as evaluation indicators of AGC after NAC and calculate area under the curve (AUC). RESULTS: There were significant differences in BF and BV values of AGC between before and after NAC (p < 0.001), respectively, and there were obvious correlations between BF as well as BV decrease rates and pathology response grade (r = 0.660, p < 0.001; r = 0.706, p < 0.001), respectively. There were also significant differences in BF and BV decrease rates of AGC between effective and ineffective groups (P = 0.001), respectively. If BF decrease rate of 12.1% (AUC was 0.816, P = 0.005) was used as the cutoff value for chemotherapy effectiveness of AGC, the sensitivity of 82% and specificity of 84% were achieved, and if BV decrease rate of 32.8% (AUC was 0.844, P = 0.002) was used as the cutoff value for chemotherapy effectiveness of AGC, the sensitivity of 82% and specificity of 89% were achieved. CONCLUSIONS: BF and BV decrease rates have potential to be used as effective indicators to assess chemotherapy efficacy of AGC from the hemodynamics.


Asunto(s)
Terapia Neoadyuvante/métodos , Dosis de Radiación , Neoplasias Gástricas/diagnóstico por imagen , Neoplasias Gástricas/tratamiento farmacológico , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estómago/diagnóstico por imagen
15.
Environ Health Prev Med ; 22(1): 58, 2017 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-29165144

RESUMEN

BACKGROUND: Members of the genus Acanthamoeba are widely distributed throughout the world, and some of them are considered pathogenic, as they are capable of causing corneal and central nervous system diseases. In this study, we isolated Acanthamoeba strains from soil and tap water in Yanji, China. METHODS: We identified four strains of Acanthamoeba (CJY/S1, CJY/S2, CJY/S3, and CJY/W1) using mitochondrial DNA restriction fragment length polymorphism (mtDNA RFLP) analysis. Nuclear 18S rDNA sequences were used for phylogenetic analysis and species identification. RESULTS: Genotypic characterization of the isolates showed that they belonged to genotypes T4 (CJY/S1 and CJY/S2), T5 (CJY/S3), and T16 (CJY/W1). Sequence differences between CJY/S1 and Acanthamoeba castellanii Neff, CJY/S2 and Acanthamoeba KA/E7, and CJY/S3 and Acanthamoeba lenticulata 68-2 were 0.31, 0.2, and 0.26%, respectively. 18S ribosomal deoxyribonucleic acid (rDNA) of CJY/W1 had 99% sequence identity to that of Acanthamoeba sp. U/H-C1. Strains CJY/S1 and CJY/S2, isolated from soil, had similar mtDNA RFLP patterns, whereas strain CJY/W1, isolated from tap water, displayed a different pattern. CONCLUSIONS: To the best of our knowledge, this is the first report on the identification of genotypes T4, T5, and T16 from environmental sources in Yanji, China.


Asunto(s)
Acanthamoeba/genética , Acanthamoeba/aislamiento & purificación , Agua Potable/parasitología , Microbiología del Suelo , Microbiología del Agua , China , Bases de Datos de Ácidos Nucleicos , Electroforesis , Genotipo , Humanos , Filogenia , Polimorfismo de Longitud del Fragmento de Restricción , Análisis de Secuencia de ARN
16.
Environ Health Prev Med ; 21(6): 563-571, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27783315

RESUMEN

OBJECTIVES: To handle the emergence of the regional healthcare ecosystem, physicians and surgeons in various departments and healthcare institutions must process medical images securely, conveniently, and efficiently, and must integrate them with electronic medical records (EMRs). In this manuscript, we propose a software as a service (SaaS) cloud called the iMAGE cloud. METHODS: A three-layer hybrid cloud was created to provide medical image processing services in the smart city of Wuxi, China, in April 2015. In the first step, medical images and EMR data were received and integrated via the hybrid regional healthcare network. Then, traditional and advanced image processing functions were proposed and computed in a unified manner in the high-performance cloud units. Finally, the image processing results were delivered to regional users using the virtual desktop infrastructure (VDI) technology. Security infrastructure was also taken into consideration. RESULTS: Integrated information query and many advanced medical image processing functions-such as coronary extraction, pulmonary reconstruction, vascular extraction, intelligent detection of pulmonary nodules, image fusion, and 3D printing-were available to local physicians and surgeons in various departments and healthcare institutions. CONCLUSIONS: Implementation results indicate that the iMAGE cloud can provide convenient, efficient, compatible, and secure medical image processing services in regional healthcare networks. The iMAGE cloud has been proven to be valuable in applications in the regional healthcare system, and it could have a promising future in the healthcare system worldwide.


Asunto(s)
Nube Computacional/estadística & datos numéricos , Registros Electrónicos de Salud/instrumentación , Procesamiento de Imagen Asistido por Computador , Programas Informáticos , China
17.
Neurochem Res ; 40(1): 49-58, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25347963

RESUMEN

Cuprizone is a copper chelating agent able to selectively damage the white matter in the mouse brain. Recent studies have reported behavioral abnormalities relevant to some of schizophrenia symptoms. While associating white matter damage to the behavioral abnormalities, these previous studies did not rule out the possible impairment in neuronal functions in cuprizone-exposed mice. The aim of this study was to examine brain metabolites of the cuprizone-exposed mice by proton magnetic resonance spectroscopy ((1)H-MRS). The examined brain regions were the caudoputamen, midbrain, and thalamus; these subcortical regions showed different susceptibilities to cuprizone in terms of demyelination and oligodendrocyte loss in previous studies. Young C57BL/6 mice were fed a standard rodent chow without or with cuprizone (0.2 %) for 6 weeks. At the end, open-field and Y-maze tests were performed to measure the emotional and cognitive behaviors of the animals, followed by (1)H-MRS procedure to evaluate the brain metabolites. Cuprizone-exposure increased anxiety levels and impaired spatial working memory. The same treatment increased T2 signal intensity in the cerebral cortex, hippocampus, and caudoputamen, but not in the thalamus. Cuprizone-exposure decreased the concentrations of NAA and NAA+NAAG in caudoputamen, but not in thalamus and midbrain. It decreased levels of Cr+PCr, GPC+PCh and myo-inositol in all the three brain regions. These results provided neurochemical evidence for the impairment in neuronal functions by cuprizone treatment.


Asunto(s)
Química Encefálica/efectos de los fármacos , Quelantes/farmacología , Cuprizona/farmacología , Esquizofrenia/metabolismo , Animales , Ansiedad/inducido químicamente , Ansiedad/psicología , Conducta Animal/efectos de los fármacos , Cognición/efectos de los fármacos , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Memoria a Corto Plazo/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Actividad Motora/efectos de los fármacos
18.
Plants (Basel) ; 13(3)2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38337959

RESUMEN

Tea is a popular beverage with characteristic functional and flavor qualities, known to be rich in bioactive metabolites such as tea polyphenols and theanine. Recently, tea varieties with variations in leaf color have been widely used in agriculture production due to their potential advantages in terms of tea quality. Numerous studies have used genome, transcriptome, metabolome, proteome, and lipidome methods to uncover the causes of leaf color variations and investigate their impacts on the accumulation of crucial bioactive metabolites in tea plants. Through a comprehensive review of various omics investigations, we note that decreased expression levels of critical genes in the biosynthesis of chlorophyll and carotenoids, activated chlorophyll degradation, and an impaired photosynthetic chain function are related to the chlorina phenotype in tea plants. For purple-leaf tea, increased expression levels of late biosynthetic genes in the flavonoid synthesis pathway and anthocyanin transport genes are the major and common causes of purple coloration. We have also summarized the influence of leaf color variation on amino acid, polyphenol, and lipid contents and put forward possible causes of these metabolic changes. Finally, this review further proposes the research demands in this field in the future.

19.
Int J Mol Sci ; 14(1): 871-87, 2013 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-23296268

RESUMEN

A mitochondrial manganese superoxide dismutase from an invasive species of the whitefly Bemisia tabaci complex (Bt-mMnSOD) was cloned and analyzed. The full length cDNA of Bt-mMnSOD is 1210 bp with a 675 bp open reading frame, corresponding to 224 amino acids, which include 25 residues of the mitochondrial targeting sequence. Compared with various vertebrate and invertebrate animals, the MnSOD signature (DVWEHAYY) and four conserved amino acids for manganese binding (H54, H102, D186 and H190) were observed in Bt-mMnSOD. Recombinant Bt-mMnSOD was overexpressed in Escherichia coli, and the enzymatic activity of purified mMnSOD was assayed under various temperatures. Quantitative real-time PCR analysis with whiteflies of different development stages showed that the mRNA levels of Bt-mMnSOD were significantly higher in the 4th instar than in other stages. In addition, the in vivo activities of MnSOD in the whitefly were measured under various conditions, including exposure to low (4 °C) and high (40 °C) temperatures, transfer from a favorable to an unfavorable host plant (from cotton to tobacco) and treatment with pesticides. Our results indicate that the whitefly MnSOD plays an important role in cellular stress responses and anti-oxidative processes and that it might contribute to the successful worldwide distribution of the invasive whitefly.


Asunto(s)
Hemípteros/genética , Proteínas de Insectos/genética , Proteínas Mitocondriales/genética , Superóxido Dismutasa/genética , Secuencias de Aminoácidos/genética , Animales , Sitios de Unión/genética , Clonación Molecular , Estabilidad de Enzimas , Regulación del Desarrollo de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Hemípteros/enzimología , Hemípteros/crecimiento & desarrollo , Proteínas de Insectos/metabolismo , Manganeso/metabolismo , Proteínas Mitocondriales/metabolismo , Proteínas Recombinantes/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Superóxido Dismutasa/metabolismo , Temperatura
20.
Technol Health Care ; 31(S1): 357-372, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37066936

RESUMEN

BACKGROUND: 125I BT is an effective radiotherapy for prostate cancer. However, comparison data of GI and GU toxicities between BT, BT + EBRT, and EBRT-alone patient groups is limited. OBJECTIVE: To define the GI and GU toxicities in prostate cancer to prevent adverse events after treatment. METHODS: We searched published studies in PubMed, Cochrane, and Embase databases up to December 31, 2022. The endpoints were the RRs of GI and GU toxicities. Pooled data were assessed using a random-effects model. RESULTS: Fifteen eligible studies were included into this analysis. LDR-BT had significantly lower RRs than LDR-BT + EBRT for acute GI (2.13; 95% CI, 1.22-3.69; P= 0.007) and late GI toxicities (3.96; 95% CI, 1.23-12.70; P= 0.02). Moreover, EBRT had significantly higher RRs than LDR-BT for acute GU (2.32; 95% CI, 1.29-4.15; P= 0.005) and late GU toxicities (2.38; 95% CI, 1.27-4.44; P= 0.007). HDR-BT had significantly higher RRs for acute GU toxicities than LDR-BT alone (0.30; 95% CI, 0.23-0.40; P< 0.00001). CONCLUSION: The results implied that BT with and without EBRT can result in both GI and GU toxicities in patients with prostate cancer, with LDR-BT leading to a poorer urinary function than EBRT.


Asunto(s)
Braquiterapia , Neoplasias de la Próstata , Masculino , Humanos , Braquiterapia/efectos adversos , Braquiterapia/métodos , Radioisótopos de Yodo , Neoplasias de la Próstata/radioterapia , Tracto Gastrointestinal
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