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1.
J Magn Reson Imaging ; 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38970314

RESUMEN

BACKGROUND: Abnormal levels of glutamate constitute a key pathophysiologic mechanism in epilepsy. The use of glutamate chemical exchange saturation transfer (GluCEST) imaging to measure glutamate levels in pediatric epilepsy is rarely reported in research. PURPOSE: To investigate hippocampal glutamate level variations in pediatric epilepsy and the correlation between glutamate and hippocampal subregional volumes. STUDY TYPE: Cross-sectional, prospective. SUBJECTS: A total of 38 school-aged pediatric epilepsy patients with structurally normal MRI as determined by at least two independent radiologists (60% males; 8.7 ± 2.5 years; including 20 cases of focal pediatric epilepsy [FE] and 18 cases of generalized pediatric epilepsy [GE]) and 17 healthy controls (HC) (41% males; 9.0 ± 2.5 years). FIELD STRENGTH/SEQUENCE: 3.0 T; 3D magnetization prepared rapid gradient echo (MPRAGE) and 2D turbo spin echo GluCEST sequences. ASSESSMENT: The relative concentration of glutamate was calculated through pixel-wise magnetization transfer ratio asymmetry (MTRasym) analysis of the GluCEST data. Hippocampal subfield volumes were computed from MPRAGE data using FreeSurfer. STATISTICAL TESTS: This study used t tests, one-way analysis of variance, Kruskal-Wallis tests, and Pearson correlation analysis. P < 0.05 was considered statistically significant. RESULTS: The MTRasym values of both the left and right hippocampi were significantly elevated in GE (left: 2.51 ± 0.23 [GE] vs. 2.31 ± 0.12 [HCs], right: 2.50 ± 0.22 [GE] vs. 2.27 ± 0.22 [HCs]). The MTRasym values of the ipsilateral hippocampus were significantly elevated in FE (2.49 ± 0.28 [ipsilateral] vs. 2.29 ± 0.16 [HCs]). The MTRasym values of the ipsilateral hippocampus were significantly increased compared to the contralateral hippocampus in FE (2.49 ± 0.28 [ipsilateral] vs. 2.35 ± 0.34 [contralateral]). No significant differences in hippocampal volume were found between different groups (left hippocampus, P = 0.87; right hippocampus, P = 0.87). DATA CONCLUSION: GluCEST imaging have potential for the noninvasive measurement of glutamate levels in the brains of children with epilepsy. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 1.

2.
J Magn Reson Imaging ; 58(5): 1431-1440, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-36808678

RESUMEN

BACKGROUND: Glutamate dysregulation is one of the key pathogenic mechanisms of major depressive disorder (MDD), and glutamate chemical exchange saturation transfer (GluCEST) has been used for glutamate measurement in some brain diseases but rarely in depression. PURPOSE: To investigate the GluCEST changes in hippocampus in MDD and the relationship between glutamate and hippocampal subregional volumes. STUDY TYPE: Cross-sectional. SUBJECTS: Thirty-two MDD patients (34% males; 22.03 ± 7.21 years) and 47 healthy controls (HCs) (43% males; 22.00 ± 3.28 years). FIELD STRENGTH/SEQUENCE: 3.0 T; magnetization prepared rapid gradient echo (MPRAGE) for three-dimensional T1-weighted images, two-dimensional turbo spin echo GluCEST, and multivoxel chemical shift imaging (CSI) for proton magnetic resonance spectroscopy (1 H MRS). ASSESSMENT: GluCEST data were quantified by magnetization transfer ratio asymmetry (MTRasym ) analysis and assessed by the relative concentration of 1 H MRS-measured glutamate. FreeSurfer was used for hippocampus segmentation. STATISTICAL TESTS: The independent sample t test, Mann-Whitney U test, Spearman's correlation, and partial correlation analysis were used. P < 0.05 was considered statistically significant. RESULTS: In the left hippocampus, GluCEST values were significantly decreased in MDD (2.00 ± 1.08 [MDD] vs. 2.62 ± 1.41 [HCs]) and showed a significantly positive correlation with Glx/Cr (r = 0.37). GluCEST values were significantly positively correlated with the volumes of CA1 (r = 0.40), subiculum (r = 0.40) in the left hippocampus and CA1 (r = 0.51), molecular_layer_HP (r = 0.50), GC-ML-DG (r = 0.42), CA3 (r = 0.44), CA4 (r = 0.44), hippocampus-amygdala-transition-area (r = 0.46), and the whole hippocampus (r = 0.47) in the right hippocampus. Hamilton Depression Rating Scale scores showed significantly negative correlations with the volumes of the left presubiculum (r = -0.40), left parasubiculum (r = -0.47), and right presubiculum (r = -0.41). DATA CONCLUSION: GluCEST can be used to measure glutamate changes and help to understand the mechanism of hippocampal volume loss in MDD. Hippocampal volume changes are associated with disease severity. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 1.


Asunto(s)
Trastorno Depresivo Mayor , Masculino , Humanos , Femenino , Trastorno Depresivo Mayor/diagnóstico por imagen , Ácido Glutámico , Estudios Transversales , Depresión , Hipocampo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos
3.
Eur Radiol ; 33(6): 4214-4222, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36600123

RESUMEN

OBJECTIVES: To elucidate the change in glutamate levels in preterm infants at different gestational ages by glutamate chemical exchange saturated transfer (GluCEST) magnetic resonance imaging and to compare the difference in glutamate levels among different brain regions between very early preterm infants and middle and late preterm infants. METHODS: Fifty-three preterm infants (59% males; median gestational age = 33.6 weeks) underwent MRI, including conventional MRI and GluCEST. The original data were postprocessed in MATLAB. Correlation analysis was used to determine the relationship between the MTRasym and gestational age. The differences in MTRasym signals among different ROIs were statistically analysed by one-way analysis of variance (ANOVA). The MTRasym difference of the bilateral hemispherical ROI was compared by a paired T test. RESULTS: In all ROIs, glutamate concentration was positively correlated with gestational age. The glutamate concentration in the thalamus was higher than that in the frontal lobe in very early, middle and late preterm infants. A difference in glutamate concentration was not found in the bilateral ROIs. CONCLUSIONS: The concentration of glutamate in the brains of preterm infants of different gestational ages increased with gestational age, which may be one of the factors contributing to the higher incidence of neurodevelopmental dysfunction in very early preterm infants compared to that in middle and late preterm infants. Meanwhile, the glutamate concentrations among different brain regions were also diverse. KEY POINTS: • The glutamate concentration was positively correlated with gestational age in preterm infants of the brain. • Glutamate concentrations were dissimilar in different brain regions of preterm infants. • Glutamate concentration during the process of brain development in premature infants was not found to be asymmetric.


Asunto(s)
Enfermedades del Prematuro , Recien Nacido Prematuro , Lactante , Masculino , Recién Nacido , Humanos , Femenino , Edad Gestacional , Proyectos Piloto , Ácido Glutámico , Encéfalo/diagnóstico por imagen , Encéfalo/patología
4.
Cell Mol Biol (Noisy-le-grand) ; 69(7): 45-50, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37715432

RESUMEN

LncRNA has been validated to be related to different cancers, whereas its regulation mechanism in hepatocellular carcinoma (HCC) is poorly known. In this study, LOXL1-AS1 was overexpressed in HCC cell lines, and LOXL1-AS1 knockdown repressed cell proliferation and stimulated apoptosis in HCC. Besides, the activating role of LOXL1-AS1 in the AKT pathway was also confirmed. Further, miR-1224-5p was sponged by LOXL1-AS1, and overexpression exerted inhibitory function in HCC. Moreover, ITPRIPL2 as amiR-1224-5ptarget gene. Meanwhile, ITPRIPL2 deficiency suppressed HCC cell proliferation. Finally, miR-1224-5p inhibitor reversed the hindering role of LOXL1-AS1 depletion in HCC cell proliferation and AKT pathway, and this rescuing effect was offset by ITPRIPL2 silencing. In summary, LOXL1-AS1 induced cell proliferation and suppresses cell apoptosis in primary HCCvia activating AKT pathway, sponging miR-1224-5p and upregulating ITPRIPL2, which may provide some fresh thoughts for researches about the molecular regulation mechanism of lncRNA in HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroARNs , ARN Largo no Codificante , Humanos , Carcinoma Hepatocelular/genética , Proliferación Celular/genética , Neoplasias Hepáticas/genética , MicroARNs/genética , Proteínas Proto-Oncogénicas c-akt , ARN Largo no Codificante/genética
5.
Oncol Res ; 27(3): 301-309, 2019 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-29562958

RESUMEN

Our study aimed to investigate the roles and possible regulatory mechanism of miR-1277 in the development of hepatocellular carcinoma (HCC). HCC patients were identified from patients who were diagnosed with focal liver lesions using magnetic resonance imaging (MRI). The expression levels of miR-1277 in the serum of HCC patients and HepG2 cells were measured. Then miR-1277 mimic, miR-1277 inhibitor, or scramble RNA was transfected into HepG2 cells. The effects of miR-1277 overexpression and suppression on HepG2 cell proliferation, migration, and invasion were then investigated. Additionally, the expression levels of epithelial-mesenchymal transition (EMT)-related markers, including E-cadherin, ß-catenin, and vimentin, were detected. Target prediction and luciferase reporter assay were performed to explore the potential target of miR-1277. miR-1277 was significantly downregulated in the serum of HCC patients and HepG2 cells. Suppression of miR-1277 promoted HepG2 cell proliferation, migration, and invasion, whereas overexpression of miR-1277 had opposite effects. In addition, after miR-1277 was suppressed, the expressions of E-cadherin and ß-catenin were significantly increased, while the expressions of vimentin were markedly decreased. Bone morphogenetic protein 4 (BMP4) was identified as the direct target of miR-1277. Knockdown of BMP4 reversed the effects of miR-1277 suppression on HepG2 cell migration and invasion, as well as the expressions of E-cadherin, ß-catenin, and vimentin. Our results indicate that downregulation of miR-1277 may promote the migration and invasion of HepG2 cells by targeting BMP4 to induce EMT. Combination of MRI and miR-1277 level will facilitate the diagnosis and treatment of HCC.


Asunto(s)
Proteína Morfogenética Ósea 4/genética , Carcinoma Hepatocelular/genética , Movimiento Celular/genética , Proliferación Celular/genética , Neoplasias Hepáticas/genética , MicroARNs/genética , Cadherinas/genética , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Regulación hacia Abajo/genética , Transición Epitelial-Mesenquimal/genética , Regulación Neoplásica de la Expresión Génica/genética , Células Hep G2 , Humanos , Neoplasias Hepáticas/patología , Imagen por Resonancia Magnética/métodos , Vimentina/genética , beta Catenina/genética
6.
Medicine (Baltimore) ; 97(18): e0624, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29718873

RESUMEN

BACKGROUND: This study aimed to describe clearly the normal imaging features of the meniscal roots on the magnetic resonance imaging (MRI) with a 3-dimensional (3D) proton density-weighted (PDW) sequence at 3T. METHODS: A total of 60 knees of 31 young asymptomatic volunteers were examined using a 3D MRI. The insertion patterns, constitution patterns, and MR signals of the meniscal roots were recorded. RESULTS: The anterior root of the medial meniscus (ARMM), the anterior root of the lateral meniscus (ARLM), and the posterior root of the medial meniscus (PRMM) had 1 insertion site, whereas the posterior root of the lateral meniscus (PRLM) can be divided into major and minor insertion sites. The ARLM and the PRMM usually consisted of multiple fiber bundles (≥3), whereas the ARMM and the PRLM often consisted of a single fiber bundle. The ARMM and the PRLM usually appeared as hypointense, whereas the ARLM and the PRMM typically exhibited mixed signals. CONCLUSIONS: The meniscal roots can be complex and diverse, and certain characteristics of them were observed on 3D MRI. Understanding the normal imaging features of the meniscal roots is extremely beneficial for further diagnosis of root tears.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Meniscos Tibiales , Adulto , China , Femenino , Voluntarios Sanos , Humanos , Imagenología Tridimensional/métodos , Masculino , Meniscos Tibiales/anatomía & histología , Meniscos Tibiales/diagnóstico por imagen , Valores de Referencia , Lesiones de Menisco Tibial/diagnóstico
7.
Parasitol Int ; 65(5 Pt A): 422-3, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27276429

RESUMEN

Infection of Taenia ovis metacestodes in sheep or goats causes great economic losses due to condemnation of carcasses. T. ovis infection is not formally recorded in China to date. In October, 2015, T. ovis infection occurred in Jingtai County, China, and 113 of 192 sheep from one farm were infected. Cysts resided in the cardiac and skeletal muscle, and evaginated metacestodes had four suckers and scolex armed with approximately 23 hooks. Using cox1 and nad1 as molecular markers, the sample was further identified and the results showed that the cox1 and nad1 nucleotide sequences of the sample shared 99% identity with that of T. ovis and 75%-91.3% with those of other Taenia species. Taken together, these results confirm the first occurrence of T. ovis in China.


Asunto(s)
Corazón/parasitología , Músculo Esquelético/parasitología , Enfermedades de las Ovejas/epidemiología , Taenia/clasificación , Taenia/genética , Teniasis/veterinaria , Animales , Animales Domésticos/parasitología , Secuencia de Bases , China/epidemiología , Ciclooxigenasa 1/genética , ADN de Helmintos/genética , Granjas , Tipificación Molecular , NADH Deshidrogenasa/genética , Análisis de Secuencia de ADN , Ovinos , Enfermedades de las Ovejas/parasitología , Taenia/anatomía & histología , Taenia/aislamiento & purificación , Teniasis/epidemiología , Teniasis/parasitología
8.
Infect Genet Evol ; 45: 408-414, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27282470

RESUMEN

The metacestode of Echinococcus shiquicus has been recorded previously in the lung and liver of its intermediate host, the plateau pika (Ochotona curzoniae), but there is limited information regarding other organ sites. There is also limited evidence of intra-specific genetic variation within E. shiquicus. A PCR-amplified mitochondrial (mt) nad1 gene fragment (approximately 1400bp in size), with unique EcoRI and SspI restriction sites, was used to distinguish cysts or cyst-like lesions of E. shiquicus from E. multilocularis. Then, the complete mt nad1 and cox1 genes for the E. shiquicus isolates were amplified and sequenced. Phylogenetic tree and haplotype network analyses for the isolates were then generated based on a concatenated dataset of the nad1 and cox1 genes using the neighbour-joining (NJ) method and TCS1.21 software. Nineteen of eighty trapped pikas were found to harbor cysts (71 in total) when dissected at the survey site. Seventeen animals had cysts (fertile) present only in the lungs, one animal had fertile cysts in the lungs and spleen, and one individual had an infertile kidney cyst. Restriction endonuclease analysis of a fragment of the nad1 gene indicated all the cysts were due to E. shiquicus. Genetic diversity analysis revealed that the nad1 and cox1 genes varied by 0.1-1.2% and 0.1-1.0%, respectively. Haplotype network analysis of the concatenated nad1 and cox1 sequences of the isolates showed they were classified into at least 6 haplotypes, and different haplotype percentages ranged from 4.2% to 29.6%. Although, high haplotype diversity was evident in the study area, the complete nad1 and cox1 gene sequences obtained indicated that all samples represented isolates of E. shiquicus. The study has also provided a new PCR-restriction endonuclease-based method to rapidly distinguish E. shiquicus from E. multilocularis which provides a useful tool for epidemiological investigations where the two species overlap.


Asunto(s)
Echinococcus/genética , Variación Genética/genética , Lagomorpha/parasitología , Animales , China , Quistes/parasitología , Quistes/patología , Equinococosis/parasitología , Equinococosis/patología , Haplotipos/genética , Pulmón/parasitología , Pulmón/patología , Filogenia
10.
Parasit Vectors ; 7: 254, 2014 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-24886279

RESUMEN

BACKGROUND: Alveolar echinococcosis, caused by the metacestode larval stage of Echinococcus multilocularis, is a zoonosis of public health significance and is highly prevalent in northwest China. To effectively monitor its transmission, we developed a new rapid and cheap diagnostic assay, based on loop-mediated isothermal amplification (LAMP), to identify canine definitive hosts infected with E. multilocularis. METHODS: The primers used in the LAMP assay were based on the mitochondrial nad5 gene of E. multilocularis and were designed using Primer Explorer V4 software. The developed LAMP assay was compared with a conventional PCR assay, using DNA extracted from the feces of dogs experimentally infected with E. multilocularis, on 189 dog fecal samples collected from three E. multilocularis-endemic regions in Qinghai province, the People's Republic of China, and 30 negative control copro-samples from dogs from an area in Gansu province that had been subjected to an intensive de-worming program. Light microscopy was also used to examine the experimentally obtained and field collected dog copro-samples for the presence of E. multilocularis eggs. RESULTS: The E. multilocularis-positivity rates obtained for the field-collected fecal samples were 16.4% and 5.3% by the LAMP and PCR assays, respectively, and all samples obtained from the control dogs were negative. The LAMP assay was able to detect E. multilocularis DNA in the feces of experimentally infected dogs at 12 days post-infection, whereas the PCR assay was positive on the 17th day and eggs were first detectable by light microscopy at day 44 post-challenge. CONCLUSION: The earlier specific detection of an E. multilocularis infection in dog copro-samples indicates that the LAMP assay we developed is a realistic alternative method for the field surveillance of canines in echinococcosis-endemic areas.


Asunto(s)
Enfermedades de los Perros/parasitología , Equinococosis Hepática/veterinaria , Echinococcus multilocularis/aislamiento & purificación , Técnicas de Amplificación de Ácido Nucleico/veterinaria , Animales , Enfermedades de los Perros/epidemiología , Perros , Equinococosis , Equinococosis Hepática/diagnóstico , Echinococcus multilocularis/genética , Heces/parasitología , Humanos , Ratones , Técnicas de Amplificación de Ácido Nucleico/métodos , Sensibilidad y Especificidad , Zoonosis
11.
PLoS One ; 9(7): e100877, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25007051

RESUMEN

BACKGROUND: Cystic echinococcosis is highly prevalent in northwest China. A cost-effective, easy to operate diagnostic tool with high sensitivity and specificity would greatly facilitate the monitoring of Echinococcus infections in canine definitive hosts. METHODS: The primers used in the LAMP assay were based on the mitochondrial nad5 gene of E. granulosus sensu stricto (E. granulosus s.s., or E.g.s.s.) and were designed using Primer Explorer V4 software. The developed LAMP assay was compared with a conventional PCR method, copro-ELISA and microscopy, using the faeces of dogs experimentally infected with E.g.s.s., and field-collected faeces of domestic dogs including 190 from Qinghai province highly endemic for E.g.s.s. and 30 controls from an area in Gansu, where a domestic dog de-worming program was in operation. RESULTS: The positivity rates obtained for the field-collected faecal samples were 12.6%, 1.6% and 2.1% by the LAMP, PCR and copro-ELISA assays, respectively. All samples obtained from the control dogs were negative. Compared with the conventional PCR, the LAMP assay provided 88.8% specificity and 100% sensitivity. The higher sensitivity of the LAMP method was also shown by the fact that it could detect the presence of laboratory challenge dog infections of E. granulsous s.s. four days earlier than the PCR method. Three copro-samples shown positive by the commercial copro-ELISA were all negative by LAMP, PCR and microscopy, which suggests these samples may have originated from another infection rather than E. granulsous s.s., possibly E. shiquicus or E. Canadensis, which is also present in China. CONCLUSIONS: We have developed a potentially useful surveillance tool for determining the prevalence of canine E. granulosus s.s. infections in the field. The LAMP assay may lead to a more cost-effective and practicable way of tracking Echinococcus infections in canids, especially when combined with the copro-ELISA.


Asunto(s)
Enfermedades de los Perros/diagnóstico , Equinococosis/veterinaria , Echinococcus granulosus/genética , Animales , ADN de Helmintos/genética , Enfermedades de los Perros/parasitología , Perros , Equinococosis/diagnóstico , Equinococosis/parasitología , Ensayo de Inmunoadsorción Enzimática , Monitoreo Epidemiológico , Heces/parasitología , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico , Prevalencia , Sensibilidad y Especificidad
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