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1.
Brain Imaging Behav ; 16(2): 728-737, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34535879

RESUMEN

The aim of this study was to investigate the abnormities in functional connectivity (FC) within each modular network and between modular networks in patients with systemic lupus erythematosus (SLE). Twelve meaningful modular networks were identified via independent component analysis from 41 patients and 40 volunteers. Parametric tests were used to compare the intra- and intermodular FC between the groups. Partial correlation analysis was used to seek the relationships between abnormal FCs and the clinical data. Compared to the controls, SLE patients showed decreased intramodular FC in the anterior default mode network (aDMN), posterior default mode network (pDMN), ventral attention network (VAN), and sensorimotor network (SMN) and increased intramodular FC in the medial visual network (mVN) and left frontoparietal network. In addition, SLE patients showed decreased intermodular FC between the SMN and the lateral visual network (lVN), between the SMN and the VAN, and between the pDMN and the lVN and exhibited increased intermodular FC between the SMN and the salience network (SAN), between the pDMN and the SAN, and between the aDMN and the VAN. Moreover, we found several correlations among the abnormal FCs and the Mini-Mental State Examination in SLE patients. Mild cognitive impairment is compensated by the hyperconnectivity between the aDMN and the VAN, while severe cognitive impairment tends to be compensated by the hyperconnectivity between the SMN and the SAN. The FC value between the SMN and the SAN and between the aDMN and the VAN may serve as neuroimaging markers for monitoring cognitive progression in SLE patients.


Asunto(s)
Disfunción Cognitiva , Lupus Eritematoso Sistémico , Encéfalo/diagnóstico por imagen , Mapeo Encefálico/métodos , Disfunción Cognitiva/diagnóstico por imagen , Humanos , Lupus Eritematoso Sistémico/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos
2.
Huan Jing Ke Xue ; 41(10): 4701-4710, 2020 Oct 08.
Artículo en Chino | MEDLINE | ID: mdl-33124403

RESUMEN

A field experiment was carried out to investigate the effects of different rice-rape rotation systems on methane and nitrous oxide emissions, which were measured using the static chamber/gas chromatography method, prediction of their global warming potentials (GWP), and greenhouse gas intensity (GHGI) in paddy fields. The results showed that the average cumulative emissions of CH4from a double cropping paddy field, single season rice field (including middle or late), rape field, and leisure land were 135.25, 55.64, 5.05, and 1.89 kg ·hm-2, respectively. The CH4 emission during the rice season accounted for 91.8%-98.5% of the annual CH4 emission in different rotation years, and the contents of dissolved organic carbon in paddy soil exhibited a significantly positive correlation with CH4 emission. The CH4 emission in conventional late rice paddy was 18.7% higher than that of hybrid late rice paddy (P<0.05). The average cumulative emissions of N2O from double cropping paddy field, single season rice field (including middle or late), rape field, and leisure land were 0.94, 0.64, 1.38, and 0.24 kg ·hm-2, respectively. Out of the total annual N2O emission, 57.2% to 70.2% was from the rape field; 17.8% and 30.6% was due to the winter fallow treatments with previous crop type of double corpping rice and single season rice, respectively. There was no significant difference in N2O emission between hybrid rice and conventional rice paddy fields. The GWP of double cropping rice-winter fallow and double cropping rice-rape was higher than that of rice-rape and rice-winter fallow, and the GWP of CH4 in rice season accounted for 71.2% to 90.9% of the annual GWP of rotation. The highest treatment of GHGI was rice-rice-rape, and the treatment of rice-oil and rice-winter slack was lower. According to the comprehensive environmental and economic benefits, the late hybrid rice-rape patterns should be selected to reduce greenhouse gases in multiple cropping rice fields of South China.


Asunto(s)
Óxido Nitroso , Oryza , Agricultura , China , Calentamiento Global , Metano/análisis , Óxido Nitroso/análisis , Rotación , Suelo
3.
Int J Clin Exp Med ; 8(5): 7467-76, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26221290

RESUMEN

POEMS syndrome is a rare plasmacyte-associated disease, one of the major diagnostic criteria of which is sclerotic bone lesion. To detect bone lesions in POEMS syndrome, which imaging method should be routinely applied and what characteristics they display are still unconfirmed. We analyzed clinical data and imaging characteristics of bone lesions in 22 patients with POEMS using multimodal methods, including conventional X-ray, computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography/computed tomography (PET/CT). Images on X-ray and CT exhibited plaque-like high-density for osteosclerotic lesions and punched-out low-density appearance for osteolytic ones. X-ray had advantage in detecting bone lesions in skull, extremity long bones, clavicle, and scapula, while CT could display sharp outline of lesions and was more sensitive than X-ray in detecting the small lesions. Osteosclerotic lesions on MRI demonstrated decreased signal intensity on both T1 and T2-weighted sequences, while osteolytic lesions or osteolytic part of mixed lesions showed high signal intensity on T2-weighted sequences. MRI had same sensitivity as CT, but with superiority in distinguishing the active osteolytic lesions from the osteosclerotic ones. PET-CT showed (18)F-FDG uptake was normal in the majority of osteosclerotic lesions, and slightly increased in mixed ones, but obviously elevated in osteolytic ones. PET/CT was less sensitive in detecting osteosclerotic lesions than in detecting osteolytic ones. In conclusion, to detect bone lesions in POEMS, conventional X-ray scan should be first performed, further followed by more sensitive CT or MRI. PET-CT is optional when the osteolytic lesions are suspected.

4.
Radiology ; 277(1): 95-103, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25880263

RESUMEN

PURPOSE: To prospectively assess the feasibility of using virtual iron content (VIC) imaging at dual-energy computed tomography (CT) to evaluate the liver iron content (LIC) in patients suspected of having liver iron overload and to compare the LIC grading performance of VIC imaging and magnetic resonance (MR) imaging. MATERIALS AND METHODS: This study was approved by the institutional review board, and informed consent was obtained from all patients. Fifty-six patients suspected of having liver iron overload (serum ferritin concentrations >500 µg/L) underwent unenhanced dual-energy CT and MR imaging of the liver. MR imaging-measured LICs were obtained in 34 of the 56 patients. VIC images were generated with dual-energy analysis. R2* and MR-measured LIC were obtained with gradient-echo and spin-echo sequences, respectively. Correlations between CT and MR measurements were analyzed. The diagnostic performance of VIC and R2* in the differentiation of different LIC thresholds were evaluated with receiver operating characteristic (ROC) analysis. RESULTS: Hepatic VIC showed significant correlation with R2* and MR-measured LIC (r = 0.885 and 0.871, respectively; P < .0001). To differentiate among different LIC thresholds of 1.8, 3.2, 7.0, and 15.0 mg of iron per gram of dry tissue, the corresponding optimal cutoff values for VIC were 2.50, 5.13, 8.93, and 17.97 HU, respectively. At a LIC threshold of 7.0 mg of iron per gram of dry tissue or higher, 100% sensitivity (15 of 15 patients) and 100% specificity (19 of 19 patients) were obtained for VIC. There was no significant difference between VIC and R2* (area under the ROC curve, 0.964 vs 0.993, respectively; P = .299) in grading LIC levels at a LIC threshold of 3.2 mg of iron per gram of dry tissue or higher. Conclusion Hepatic VIC is a potential index for accurately evaluating and grading clinically significant liver iron accumulation, with a diagnostic performance similar to that of MR imaging.


Asunto(s)
Sobrecarga de Hierro/diagnóstico , Hierro/análisis , Hepatopatías/diagnóstico , Hígado/química , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Exactitud de los Datos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
5.
Eur Radiol ; 25(9): 2657-64, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25773943

RESUMEN

OBJECTIVES: To assess the accuracy of liver iron content (LIC) quantification and grading ability associated with clinical LIC stratification using virtual iron concentration (VIC) imaging on dual-energy CT (DECT) in an iron overload rabbit model. METHODS: Fifty-one rabbits were prepared as iron-loaded models by intravenous injection of iron dextran. DECT was performed at 80 and 140 kVp. VIC images were derived from an iron-specific algorithm. Postmortem LIC assessments were conducted on an inductively coupled plasma (ICP) spectrometer. Correlation between VIC and LIC was analyzed. VIC were stratified according to the corresponding clinical LIC thresholds of 1.8, 3.2, 7.0, and 15.0 mg Fe/g. Diagnostic performance of stratification was evaluated by receiver operating characteristic analysis. RESULTS: VIC linearly correlated with LIC (r = 0.977, P < 0.01). No significant difference was observed between VIC-derived LICs and ICP (P > 0.05). For the four clinical LIC thresholds, the corresponding cutoff values of VIC were 19.6, 25.3, 36.9, and 61.5 HU, respectively. The highest sensitivity (100%) and specificity (100 %) were achieved at the threshold of 15.0 mg Fe/g. CONCLUSIONS: Virtual iron concentration imaging on DECT showed potential ability to accurately quantify and stratify hepatic iron accumulation in the iron overload rabbit model. KEY POINTS: • Virtual iron concentration (VIC) linearly correlates with liver iron content (LIC). • VIC accurately quantifies LIC. • VIC accurately grades LIC based on clinical LIC stratification.


Asunto(s)
Sobrecarga de Hierro/diagnóstico por imagen , Hígado/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Algoritmos , Animales , Modelos Animales de Enfermedad , Hierro/análisis , Masculino , Curva ROC , Conejos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
6.
Zhonghua Yi Xue Za Zhi ; 93(35): 2830-3, 2013 Sep 17.
Artículo en Chino | MEDLINE | ID: mdl-24360184

RESUMEN

OBJECTIVE: To develop a magnetic nanoparticles based magnetic resonance (MR) probe targeting CD40 mutant in the imaging of breast cancer cells in vitro. METHODS: For preparing an immunologically competent probe, monoclonal antibody was conjugated with ultrasmall superparamagnetic iron oxide (USPIO) particles basing on chemical cross-linking method.Its bioactivity was analyzed with flow cytometry, confocal microscopy and Prussian blue staining. The probe's cell MR imaging in vitro was conducted on breast cancer cells (M231) high expressing CD40 mutant. The signal data from different groups were collected and analyzed with one-way variance and least significant difference-t test. RESULTS: The molecular probe carrying nanoparticles and CD40 mutant antibody was constructed and separated successfully. The probe had similar magnetic property compared with original USPIO particles.It could recognize CD40 mutant on breast cancer cells (M231) with high specificity. MR cell imaging in vitro shows that T2 and T2(*) obviously shortened after probe binding with M231 cells and T2 weighted imaging become darker than control groups, the time of T2 is 5H6-USPIO (51.66 ± 5.31) , 5C11-USPIO (92.89 ± 4.72), USPIO (64.56 ± 3.85) ms. The T2 and T2(*) relaxation time of experiment group was shorter than control groups with statistical significance (P < 0.01) . CONCLUSION: MR molecular probe targeting CD40 mutant may bind with breast cancer cells (M231) to provide further in vivo animal MR imaging. And CD40 mutant is expected to provide a new target for MR molecular imaging of breast cancer.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Imagen por Resonancia Magnética , Antígenos CD40/genética , Línea Celular Tumoral , Femenino , Humanos , Magnetismo , Sondas Moleculares , Nanopartículas
7.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 2): o338, 2011 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-21523021

RESUMEN

The title compound, C(21)H(22)O(5), crystallizes with three mol-ecules in the asymmetric unit. In one mol-ecule, two methyl groups are disordered over two positions with a site occupation factor of 0.72 (2) for the major occupancy site. The benzene rings make dihedral angles of 35.3 (6), 29.7 (6) and 40.6 (7)° in the three molecules.

8.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 6): o1433, 2010 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-21579508

RESUMEN

In the title compound, C(12)H(14)O(4)·H(2)O, the dihydro-benzo-furan ring adopts an envelope conformation with the substituted C atom 0.142 (1) Šout of the least-squares plane. In the crystal, the components are linked via inter-molecular O(water)-H⋯O and O-H⋯O(water) hydrogen-bonding inter-actions, forming a three-dimensional network.

9.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 6): o1460, 2010 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-21579528

RESUMEN

In the title compound, C(19)H(21)NO(3), the dihedral angle between the mean planes of the two benzene rings is 38.13 (12)°. The furan ring adopts an envelope-like conformation with the C atom bonded to the dimethyl groups displaced by 0.356 (2) Šfrom the plane through the other four atoms. In the crystal, mol-ecules are linked into inversion dimers by weak C-H⋯O inter-molecular inter-actions.

10.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 3): o567, 2010 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-21580335

RESUMEN

The title compound, C(14)H(18)O(2), was obtained as a by-product during the preparation of carbofuran phenol. The two dihydro-furan rings are in envelope conformations.

11.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 25(10): 910-3, 2009 Oct.
Artículo en Chino | MEDLINE | ID: mdl-19811740

RESUMEN

AIM: To prepare and characterize a mouse anti-human CD40 mutant monoclonal mAb. METHODS: Female BALB/c mice of 6-8 weeks old were immunized with CD40 mutant transfectant (L929-CD40mu) as immunogen. The spleen B cells of the mice were fused with Sp2/0 myeloma cells.The hybridoma cells were screened with CD40 mutant transfectant (L929-CD40mu) by FCM. Fast-strip analysis was performed to identify Ig subclass of this mAb. The epitope recognized by this mAb was detected by Bio-5C11 competitive assay. Western blot technique was adopted to identify the mAb. The proliferation of tumor cells in vitro was analyzed by MTT assay and apoptosis of tumor cells in vitro was analyzed by PI-annexin V assay. RESULTS: One hybridoma cell line named 10C5 was obtained, which had the property of secreting anti-human CD40 mutant monoclonal antibody continuously and steadily. This mAb specifically recognized human CD40 mutant molecule and induced the apoptosis of tumor cells in vitro. CONCLUSION: One hybridoma cell line which can secret a mouse anti-human CD40 mutant mAb has been prepared successfully. This mAb can inhibit the growth of tumor cells expressing CD40 mutant and induce their apoptosis in vitro.


Asunto(s)
Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales/inmunología , Antígenos CD40/inmunología , Mutación , Animales , Apoptosis/inmunología , Línea Celular Tumoral , Proliferación Celular , Femenino , Regulación de la Expresión Génica/inmunología , Humanos , Hibridomas/citología , Ratones , Ratones Endogámicos BALB C
12.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 24(6): 590-3, 2008 Jun.
Artículo en Chino | MEDLINE | ID: mdl-18538090

RESUMEN

AIM: To prepare iodine-125 labeled anti-human CD40 monoclonal antibody 5H6 ((125)I-5H6) and investigate the binding properties of (125)I-5H6 to HO8910 cells in vitro. METHODS: The mAb 5H6 was labeled with Na (125)I using chloramine-T method. The labeling efficiency and radiochemical purity of (125)I-5H6 were measured by paper chromatography. The stability of (125)I-5H6 in vitro was monitored by trichloroacetic acid (TCA) precipitation. The dissociation constant (K(d)) of (125)I-5H6 from HO8910 cells and the numbers of maximum binding sites (B(max)) were obtained by Scatchard analysis. Immunoreactivity of (125)I-5H6 to HO8910 cells was determined by "Lindmo" assay and its improved method. Internalization and retention of (125)I- 5H6 by HO8910 cells were studied by cell binding experiments. RESULTS: (1)The labeling efficiency of (125)I-5H6 was (85.4+/-5.2)% and its radiochemical purity was (99.2+/-0.5)%. (2)Radiochemical purity of (125)I-5H6 was (80.3+/-4.7)% after 7 days in 4 Degrees Celsius PB (phosphate buffer) and (95.3+/-0.8)% after 24 hours in 37 Degrees Ceslius plasma. (3)At 4 Degrees Celsius, K(d) for (125)I-5H6 to HO8910 cells was (0.711+/-0.06) nmol/L and Bmax was (2.17+/-0.08)x10(5) sites/cell. (4)Immunoreactivity of (125)I-5H6 was (38.6+/-5.4)%. (5)Retention rate of (125)I-5H6 with HO8910 cells was (89.8+/-6.0)% after 2 hours at 4 Degrees Celsius and internalization rate of (125)I-5H6 by HO8910 cells was (54.9+/-2.6)% after 2 hours at 37 Degrees Celsius. CONCLUSION: (125)I-5H6 possesses good labeling efficiency and perfect radiochemical purity. (125)I-5H6 has suitable stability in vitro and its immunoreactivity was not low. The high affinity of (125)I-5H6 with HO8910 cells will benefit further animal study in vivo.


Asunto(s)
Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/inmunología , Antígenos CD40/inmunología , Neoplasias Ováricas/inmunología , Línea Celular Tumoral , Femenino , Humanos , Radioisótopos de Yodo/química , Marcaje Isotópico , Unión Proteica
13.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 23(9): 841-3, 2007 Sep.
Artículo en Chino | MEDLINE | ID: mdl-17825232

RESUMEN

AIM: To prepare a novel functional mouse anti-human CD40 monoclonal mAb. METHODS: Female BALB/c mice of 6-8 weeks old were immunized with CD40 transfectant (L929-CD40) as immunogen. The spleen B cells of the mice were fused with Sp2/0. The hybridoma cells were screened with CD40 transfectant (L929-CD40) by FCM. Fast-strip analysis was performed to identify Ig subclass of this mAb. The epitope recognized by this mAb was detected by Bio/5C11 competitive assay. The proliferation and cell cycle of tumor cells in vitro were studied by MTT assay and PI staining respectively. RESULTS: One hybridoma cell line named 2B6 was obtained, which had the property of secreting anti-human CD40 monoclonal antibody continuously and steadily. This mAb specifically recognized human CD40 molecule and promoted the proliferation of tumor cells in vitro. CONCLUSION: One hybridoma cell line which can secret a novel functional mouse anti-human CD40 mAb has been developed successfully. This mAb can specifically recognize human CD40 and influence the growth of tumor cells in vitro.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacología , Especificidad de Anticuerpos/inmunología , Antígenos CD40/inmunología , Neoplasias/patología , Animales , Anticuerpos Monoclonales/análisis , Anticuerpos Monoclonales/metabolismo , Unión Competitiva , Ciclo Celular/inmunología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta Inmunológica , Epítopos/inmunología , Femenino , Citometría de Flujo , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Hibridomas/metabolismo , Interleucina-6/metabolismo , Ratones , Ratones Endogámicos BALB C , Factores de Tiempo
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