To investigate cyclo (Arg-Gly-Asp-D-Phe-Lys) peptide (RGD)-modified PEGylated dendrimer-entrapped... more To investigate cyclo (Arg-Gly-Asp-D-Phe-Lys) peptide (RGD)-modified PEGylated dendrimer-entrapped gold nanoparticles (PEGylated Au DENPs-RGD) for targeted computed tomography (CT) imaging of breast carcinomas. PEGylated Au DENPs-RGD were synthesized and characterized. Then, the PEGylated Au DENPs-RGD for targeted CT imaging were investigated using the MDA-MB-435 cell line, an integrin-rich breast carcinoma cells, and mice with MDA-MB-435 xenograft tumors. Finally, silver enhancement staining and integrin αvβ3 immunohistochemistry of the tumors were performed. The synthesized PEGylated Au DENPs-RGD were spherical, water dispersible and biocompatible nanoprobes with a gold nanoparticle core size of 2.8 nm. Due to the presence of the Au nanoparticles, the PEGylated Au DENPs-RGD displayed a higher x-ray attenuation intensity than Omnipaque at the same Au or I concentrations. The conjugated RGD ligand can specifically identify and target overexpressed integrin receptors on MDA-MB-435 cel...
To test the feasibility of semi-quantitative dynamic contrast-enhanced magnetic resonance imaging... more To test the feasibility of semi-quantitative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters for evaluating tumor hypoxia in a maxillofacial VX2 rabbit model. Eight New Zealand rabbits were inoculated with VX2 cell solution to establish a maxillofacial VX2 rabbit model. DCE-MRI were carried out using a 1.5 Tesla scanner. Semi-quantitative DCE-MRI parameters, maximal enhancement ratio (MER) and slope of enhancement (SLE), were calculated and analyzed. The tumor samples from rabbits underwent hematoxylin-eosin (HE), pimonidazole (PIMO) and vascular endothelial growth factor (VEGF) immunohistochemistry (IHC) staining, and the PIMO area fraction and VEGF IHC score were calculated. Spearman's rank correlation analysis was used for statistical analysis. The MER values of eight VX2 tumors ranged from 1.132 to 1.773 (1.406 ± 0.258) and these values were negatively correlated with the corresponding PIMO area fraction (p = 0.0000002), but there was no significant...
To test the hypothesis that MRI can monitor intraportal vein (IPV) transcatheter delivery of clin... more To test the hypothesis that MRI can monitor intraportal vein (IPV) transcatheter delivery of clinically applicable heparin-protamine-ferumoxytol (HPF) nanocomplex-labeled natural killer (NK) cells to liver tumor. Liver tumor rat models underwent catheterization for IPV infusion of HPF-labeled NK cells (NK-92MI cell line). MRI measurements within tumor and adjacent liver tissues were compared pre- and post-NK cell infusion. Histology studies were used to identify NK cells in the target tumors. For first time, we demonstrated that MRI tracks HPF-labeled NK cells migration within liver following IPV delivery. IPV transcatheter infusion permitted selective delivery of NK cells to liver tissues and MRI allowed tracking NK cell biodistributions within the tumors.
To investigate the feasibility of blood oxygen level dependent magnetic resonance imaging (BOLD-M... more To investigate the feasibility of blood oxygen level dependent magnetic resonance imaging (BOLD-MRI) in evaluating human subcutaneous and visceral adipose tissue (AT) oxygenation status, as well as their responses to dietary salt loading/depletion, we enrolled 16 healthy subjects [mean body mass index (BMI): 24.8 ± 2.7 kg/m(2)] to conduct a dietary intervention study, beginning with a 3-day run-in period for usual diet, followed by a 7-day high-salt diet (≥ 15 g NaCl/day) and a 7-day low-salt diet (≤ 5 g NaCl/day). Abdominal BOLD-MRI scan was performed to evaluate oxygenation in waist subcutaneous and perirenal (visceral) AT. Two subjects with lower BMI were excluded because of the difficulty to identify subcutaneous AT. High salt diet led to a consistent increase in R2* signal (a parameter for increased hypoxia) both in subcutaneous and visceral AT (all P < 0.0001), which was completely regressed to baseline levels by low salt diet. In addition, subcutaneous AT R2* values at any...
To validate the feasibility of labeling Clostridium novyi-NT (C.novyi-NT) anaerobes with iron-oxi... more To validate the feasibility of labeling Clostridium novyi-NT (C.novyi-NT) anaerobes with iron-oxide nanoparticles for magnetic resonance imaging (MRI) and demonstrate the potential to use MRI to visualize intra-tumoral delivery of these iron-oxide labeled C.novyi-NT during percutaneous injection procedures. All studies were approved by IACUC. C.novyi-NT were labeled with hybrid iron-oxide Texas red nanoparticles. Growth of labeled and control samples were evaluated with optical density. Labeling was confirmed with confocal fluorescence and transmission electron microscopy (TEM). MRI were performed using a 7 Tesla scanner with T2*-weighted (T2*W) sequence. Contrast-to-noise ratio (CNR) measurements were performed for phantoms and signal-to-noise ratio (SNR) measurements performed in C57BL/6 mice (n = 12) with Panc02 xenografts before and after percutaneous injection of iron-oxide labeled C.novyi-NT. MRI was repeated 3 and 7 days post-injection. Hematoxylin-eosin (HE), Prussian blue a...
In this study, we investigated the use of high-resolution magnetic resonance imaging (MRI) method... more In this study, we investigated the use of high-resolution magnetic resonance imaging (MRI) methods for in vivo detection and quantitative characterization of colorectal tumors in the transgenic APC(Δ468) mouse model. High-resolution T(1)-weighted (T(1)W) images, T(2)-weighted (T(2)W) images, and dynamic contrast-enhanced (DCE) measurements were performed using a 7.0 T small-animal imaging system (N = 10). Individual tumors were identified on both T(1)W and T(2)W images. Twenty-eight tumors (2.8 ± 0.9 mm, mean ± SD) were detected with high-resolution MRI across a distance of roughly 3 cm from the rectum to the splenic flexure, whereas 29 tumors were found within corresponding colon tissue samples examined at gross necropsy in the same area. T(2) values were significantly different between tumor, skeletal muscle, and normal intestinal wall tissues (p < .05). For analysis of the vascular characteristics of colon tumor tissues using DCE measurements, the initial area under the curve ...
The objectives of this study were to investigate the feasibility of imaging green fluorescent pro... more The objectives of this study were to investigate the feasibility of imaging green fluorescent protein (GFP)-expressing cells labeled with iron oxide nanoparticles with the fast low-angle positive contrast steady-state free precession (FLAPS) method and to compare them with the traditional negative contrast technique. The GFP-R3230Ac cell line (GFP cell) was incubated for 24 hours using 20 microg Fe/mL concentration of superparamagnetic iron oxide (SPIO) and ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles. Cell samples were prepared for iron content analysis and cell function evaluation. The labeled cells were imaged using positive contrast with FLAPS imaging, and FLAPS images were compared with negative contrast T2*-weighted images. The results demonstrated that SPIO and USPIO labeling of GFP cells had no effect on cell function or GFP expression. Labeled cells were successfully imaged with both positive and negative contrast magnetic resonance imaging (MRI). The label...
To explore the pathogenesis of rheumatoid arthritis (RA) by studying the expression of T cell rec... more To explore the pathogenesis of rheumatoid arthritis (RA) by studying the expression of T cell receptors (TCRs). T cell receptor Vbeta (TCR Vbeta) gene usage and expression were analyzed from synovial membrane and peripheral blood of 8 RA patients, 2 osteoarthritis patients and 2 accident amputees. The complementary determining region 3 (CDR3) of 25 TCR Vbeta subfamily genes in unselected T cell populations were amplified semi-quantitatively by reverse transcription-polymerase chain reaction (RT-PCR). The products were further studied by genescan for frequency of Vbeta usage. The numbers of Vbeta subfamilies expressed by T cells from RA peripheral blood and synovial membrane were not significantly restricted. More importantly, biased Vbeta gene expression in RA synovium was observed and Vbeta6, Vbeta17, and Vbeta22 genes were the predominant subfamilies. It was noteworthy that the expression of Vbeta17 in RA synovium was significantly increased. Our data were consistent with the hypo...
Results: The common manifestations observed throughout the disease course were oral aphthae (98.4... more Results: The common manifestations observed throughout the disease course were oral aphthae (98.4%), genital aphthae (76.3%), various cutaneous lesions including erythema nodosum and pseudo-folliculitis (69.0%), inflammatory ocular disease (34.8%) and ...
The Journal of steroid biochemistry and molecular biology, 2015
We investigated the effect of ovariectomy (OVX) and 17β-estradiol (E2) replacement on both mitoch... more We investigated the effect of ovariectomy (OVX) and 17β-estradiol (E2) replacement on both mitochondrial and myocardial function in cTnT-Q92 transgenic mice generated by cardiac-restricted expression of a human hypertrophic cardiomyopathy (HCM) mutation. The cTnT-Q92 mice were ovariectomized at twenty weeks of age and were treated with either placebo (OVX group) or E2 (OVX+E2 group) for twelve weeks before being sacrificed. Wild-type and cTnT-Q92 female mice receiving sham operation were used as controls. Indices of diastolic function such as mitral early (E) and late (A) inflow as well as isovolumic relaxation time (IVRT) were measured by echocardiography. A Clark-type electrode was used to detect respiratory control, and ATP levels were determined at the mitochondrial level using HPLC. Key components related to mitochondrial energy metabolism, such as peroxisome proliferator-activated receptor α (PPARα), PPARγ coactivator 1α (PGC-1α) and nuclear respiratory factor-1 (NRF-1), were ...
A multimodal nanocomposite was designed, synthesized with super-paramagnetic core (CoFe2O4), nobl... more A multimodal nanocomposite was designed, synthesized with super-paramagnetic core (CoFe2O4), noble metal corona (Au), and semiconductor shell (TiO2). The sizes of core, core-corona, and core-corona-shell particles were determined by TEM. This multimodal nanocrystal showed promise as a contrast agent for two of the most widely used biomedical imaging techniques: magnetic resonance imaging (MRI) and X-ray computed tomography (CT). Finally, these nanocomposites were coated with a peptide SN-50. This led to their ready uptake by the cultured cells and targeted the nanocomposites to the pores of nuclear membrane. Inside cells, this nanocomposite retained its integrity as shown by X-ray fluorescence microscopy (XFM). Inside cells imaged by XFM we found the complex elemental signature of nanoconjugates (Ti-Co-Fe-Au) always co-registered in the 2D elemental map of the cell.
To develop reagents for early diagnosis and therapeutic drugs against SARS-associated coronavirus... more To develop reagents for early diagnosis and therapeutic drugs against SARS-associated coronavirus (SARS-CoV), a large (3×109) immunized human antibody library was constructed from peripheral blood mononuclear cells from six SARS convalescent patients. A single chain variable fragment antibody (N18) with high affinity against N protein of SARS-CoV was isolated. Sequence analysis revealed that the VL gene was composed of VL3h
The climate, substrate, and marine hydrodynamics of Jiangsu, China, tidal flats are suitable for ... more The climate, substrate, and marine hydrodynamics of Jiangsu, China, tidal flats are suitable for the growth of Spartina alterniflora. Out of 954km coastline, a section of 410km is protected by this plant, with a maximum width over 4km. It functions as a new pioneer stage in plant succession, as a major coastal association, profoundly affecting the coastal environment. Field studies
Purpose To test the following hypotheses in a murine model of pancreatic cancer: (a) Vaccination ... more Purpose To test the following hypotheses in a murine model of pancreatic cancer: (a) Vaccination with antigen-loaded iron-labeled dendritic cells reduces T2-weighted signal intensity at magnetic resonance (MR) imaging within peripheral draining lymph nodes ( LN lymph node s) and (b) such signal intensity reductions are associated with tumor size changes after dendritic cell vaccination. Materials and Methods The institutional animal care and use committee approved this study. Panc02 cells were implanted into the flanks of 27 C57BL/6 mice bilaterally. After tumors reached 10 mm, cell viability was evaluated, and iron-labeled dendritic cell vaccines were injected into the left hind footpad. The mice were randomly separated into the following three groups (n = 9 in each): Group 1 was injected with 1 million iron-labeled dendritic cells; group 2, with 2 million cells; and control mice, with 200 mL of phosphate-buffered saline. T1- and T2-weighted MR imaging of labeled dendritic cell mig...
Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine, Jan 24, 2014
Magnetization transfer (MT) MRI can be effective for the diagnosis of a broad range of fibrotic d... more Magnetization transfer (MT) MRI can be effective for the diagnosis of a broad range of fibrotic diseases, including liver fibrosis. However, respiratory motion, a major source of artifacts in thoracic and abdominal MR imaging, can obscure important anatomic structures, making diagnosis difficult. In this study, we explored the potential to combine free-breathing (FB) respiratory self-gating (RSG) methods with MT saturation for FB MT ratio (MTR) measurements of abdominal organs. A respiratory self-gated multiple-gradient recalled echo sequence with MT presaturation (RSG-MT GRE) was developed and applied in a series of seven normal volunteers. We compared the MTR values of liver, pancreas, kidney, spleen, and posterior paraspinal muscle measured using our RSG-MT GRE sequence and a conventional MT GRE sequence. RSG consistently reduced motion artifacts within MT-weighted images acquired during FB, improved the accuracy of FB MTR measurements, and produced comparable MTRs to breath-hold...
To investigate cyclo (Arg-Gly-Asp-D-Phe-Lys) peptide (RGD)-modified PEGylated dendrimer-entrapped... more To investigate cyclo (Arg-Gly-Asp-D-Phe-Lys) peptide (RGD)-modified PEGylated dendrimer-entrapped gold nanoparticles (PEGylated Au DENPs-RGD) for targeted computed tomography (CT) imaging of breast carcinomas. PEGylated Au DENPs-RGD were synthesized and characterized. Then, the PEGylated Au DENPs-RGD for targeted CT imaging were investigated using the MDA-MB-435 cell line, an integrin-rich breast carcinoma cells, and mice with MDA-MB-435 xenograft tumors. Finally, silver enhancement staining and integrin αvβ3 immunohistochemistry of the tumors were performed. The synthesized PEGylated Au DENPs-RGD were spherical, water dispersible and biocompatible nanoprobes with a gold nanoparticle core size of 2.8 nm. Due to the presence of the Au nanoparticles, the PEGylated Au DENPs-RGD displayed a higher x-ray attenuation intensity than Omnipaque at the same Au or I concentrations. The conjugated RGD ligand can specifically identify and target overexpressed integrin receptors on MDA-MB-435 cel...
To test the feasibility of semi-quantitative dynamic contrast-enhanced magnetic resonance imaging... more To test the feasibility of semi-quantitative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters for evaluating tumor hypoxia in a maxillofacial VX2 rabbit model. Eight New Zealand rabbits were inoculated with VX2 cell solution to establish a maxillofacial VX2 rabbit model. DCE-MRI were carried out using a 1.5 Tesla scanner. Semi-quantitative DCE-MRI parameters, maximal enhancement ratio (MER) and slope of enhancement (SLE), were calculated and analyzed. The tumor samples from rabbits underwent hematoxylin-eosin (HE), pimonidazole (PIMO) and vascular endothelial growth factor (VEGF) immunohistochemistry (IHC) staining, and the PIMO area fraction and VEGF IHC score were calculated. Spearman's rank correlation analysis was used for statistical analysis. The MER values of eight VX2 tumors ranged from 1.132 to 1.773 (1.406 ± 0.258) and these values were negatively correlated with the corresponding PIMO area fraction (p = 0.0000002), but there was no significant...
To test the hypothesis that MRI can monitor intraportal vein (IPV) transcatheter delivery of clin... more To test the hypothesis that MRI can monitor intraportal vein (IPV) transcatheter delivery of clinically applicable heparin-protamine-ferumoxytol (HPF) nanocomplex-labeled natural killer (NK) cells to liver tumor. Liver tumor rat models underwent catheterization for IPV infusion of HPF-labeled NK cells (NK-92MI cell line). MRI measurements within tumor and adjacent liver tissues were compared pre- and post-NK cell infusion. Histology studies were used to identify NK cells in the target tumors. For first time, we demonstrated that MRI tracks HPF-labeled NK cells migration within liver following IPV delivery. IPV transcatheter infusion permitted selective delivery of NK cells to liver tissues and MRI allowed tracking NK cell biodistributions within the tumors.
To investigate the feasibility of blood oxygen level dependent magnetic resonance imaging (BOLD-M... more To investigate the feasibility of blood oxygen level dependent magnetic resonance imaging (BOLD-MRI) in evaluating human subcutaneous and visceral adipose tissue (AT) oxygenation status, as well as their responses to dietary salt loading/depletion, we enrolled 16 healthy subjects [mean body mass index (BMI): 24.8 ± 2.7 kg/m(2)] to conduct a dietary intervention study, beginning with a 3-day run-in period for usual diet, followed by a 7-day high-salt diet (≥ 15 g NaCl/day) and a 7-day low-salt diet (≤ 5 g NaCl/day). Abdominal BOLD-MRI scan was performed to evaluate oxygenation in waist subcutaneous and perirenal (visceral) AT. Two subjects with lower BMI were excluded because of the difficulty to identify subcutaneous AT. High salt diet led to a consistent increase in R2* signal (a parameter for increased hypoxia) both in subcutaneous and visceral AT (all P < 0.0001), which was completely regressed to baseline levels by low salt diet. In addition, subcutaneous AT R2* values at any...
To validate the feasibility of labeling Clostridium novyi-NT (C.novyi-NT) anaerobes with iron-oxi... more To validate the feasibility of labeling Clostridium novyi-NT (C.novyi-NT) anaerobes with iron-oxide nanoparticles for magnetic resonance imaging (MRI) and demonstrate the potential to use MRI to visualize intra-tumoral delivery of these iron-oxide labeled C.novyi-NT during percutaneous injection procedures. All studies were approved by IACUC. C.novyi-NT were labeled with hybrid iron-oxide Texas red nanoparticles. Growth of labeled and control samples were evaluated with optical density. Labeling was confirmed with confocal fluorescence and transmission electron microscopy (TEM). MRI were performed using a 7 Tesla scanner with T2*-weighted (T2*W) sequence. Contrast-to-noise ratio (CNR) measurements were performed for phantoms and signal-to-noise ratio (SNR) measurements performed in C57BL/6 mice (n = 12) with Panc02 xenografts before and after percutaneous injection of iron-oxide labeled C.novyi-NT. MRI was repeated 3 and 7 days post-injection. Hematoxylin-eosin (HE), Prussian blue a...
In this study, we investigated the use of high-resolution magnetic resonance imaging (MRI) method... more In this study, we investigated the use of high-resolution magnetic resonance imaging (MRI) methods for in vivo detection and quantitative characterization of colorectal tumors in the transgenic APC(Δ468) mouse model. High-resolution T(1)-weighted (T(1)W) images, T(2)-weighted (T(2)W) images, and dynamic contrast-enhanced (DCE) measurements were performed using a 7.0 T small-animal imaging system (N = 10). Individual tumors were identified on both T(1)W and T(2)W images. Twenty-eight tumors (2.8 ± 0.9 mm, mean ± SD) were detected with high-resolution MRI across a distance of roughly 3 cm from the rectum to the splenic flexure, whereas 29 tumors were found within corresponding colon tissue samples examined at gross necropsy in the same area. T(2) values were significantly different between tumor, skeletal muscle, and normal intestinal wall tissues (p < .05). For analysis of the vascular characteristics of colon tumor tissues using DCE measurements, the initial area under the curve ...
The objectives of this study were to investigate the feasibility of imaging green fluorescent pro... more The objectives of this study were to investigate the feasibility of imaging green fluorescent protein (GFP)-expressing cells labeled with iron oxide nanoparticles with the fast low-angle positive contrast steady-state free precession (FLAPS) method and to compare them with the traditional negative contrast technique. The GFP-R3230Ac cell line (GFP cell) was incubated for 24 hours using 20 microg Fe/mL concentration of superparamagnetic iron oxide (SPIO) and ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles. Cell samples were prepared for iron content analysis and cell function evaluation. The labeled cells were imaged using positive contrast with FLAPS imaging, and FLAPS images were compared with negative contrast T2*-weighted images. The results demonstrated that SPIO and USPIO labeling of GFP cells had no effect on cell function or GFP expression. Labeled cells were successfully imaged with both positive and negative contrast magnetic resonance imaging (MRI). The label...
To explore the pathogenesis of rheumatoid arthritis (RA) by studying the expression of T cell rec... more To explore the pathogenesis of rheumatoid arthritis (RA) by studying the expression of T cell receptors (TCRs). T cell receptor Vbeta (TCR Vbeta) gene usage and expression were analyzed from synovial membrane and peripheral blood of 8 RA patients, 2 osteoarthritis patients and 2 accident amputees. The complementary determining region 3 (CDR3) of 25 TCR Vbeta subfamily genes in unselected T cell populations were amplified semi-quantitatively by reverse transcription-polymerase chain reaction (RT-PCR). The products were further studied by genescan for frequency of Vbeta usage. The numbers of Vbeta subfamilies expressed by T cells from RA peripheral blood and synovial membrane were not significantly restricted. More importantly, biased Vbeta gene expression in RA synovium was observed and Vbeta6, Vbeta17, and Vbeta22 genes were the predominant subfamilies. It was noteworthy that the expression of Vbeta17 in RA synovium was significantly increased. Our data were consistent with the hypo...
Results: The common manifestations observed throughout the disease course were oral aphthae (98.4... more Results: The common manifestations observed throughout the disease course were oral aphthae (98.4%), genital aphthae (76.3%), various cutaneous lesions including erythema nodosum and pseudo-folliculitis (69.0%), inflammatory ocular disease (34.8%) and ...
The Journal of steroid biochemistry and molecular biology, 2015
We investigated the effect of ovariectomy (OVX) and 17β-estradiol (E2) replacement on both mitoch... more We investigated the effect of ovariectomy (OVX) and 17β-estradiol (E2) replacement on both mitochondrial and myocardial function in cTnT-Q92 transgenic mice generated by cardiac-restricted expression of a human hypertrophic cardiomyopathy (HCM) mutation. The cTnT-Q92 mice were ovariectomized at twenty weeks of age and were treated with either placebo (OVX group) or E2 (OVX+E2 group) for twelve weeks before being sacrificed. Wild-type and cTnT-Q92 female mice receiving sham operation were used as controls. Indices of diastolic function such as mitral early (E) and late (A) inflow as well as isovolumic relaxation time (IVRT) were measured by echocardiography. A Clark-type electrode was used to detect respiratory control, and ATP levels were determined at the mitochondrial level using HPLC. Key components related to mitochondrial energy metabolism, such as peroxisome proliferator-activated receptor α (PPARα), PPARγ coactivator 1α (PGC-1α) and nuclear respiratory factor-1 (NRF-1), were ...
A multimodal nanocomposite was designed, synthesized with super-paramagnetic core (CoFe2O4), nobl... more A multimodal nanocomposite was designed, synthesized with super-paramagnetic core (CoFe2O4), noble metal corona (Au), and semiconductor shell (TiO2). The sizes of core, core-corona, and core-corona-shell particles were determined by TEM. This multimodal nanocrystal showed promise as a contrast agent for two of the most widely used biomedical imaging techniques: magnetic resonance imaging (MRI) and X-ray computed tomography (CT). Finally, these nanocomposites were coated with a peptide SN-50. This led to their ready uptake by the cultured cells and targeted the nanocomposites to the pores of nuclear membrane. Inside cells, this nanocomposite retained its integrity as shown by X-ray fluorescence microscopy (XFM). Inside cells imaged by XFM we found the complex elemental signature of nanoconjugates (Ti-Co-Fe-Au) always co-registered in the 2D elemental map of the cell.
To develop reagents for early diagnosis and therapeutic drugs against SARS-associated coronavirus... more To develop reagents for early diagnosis and therapeutic drugs against SARS-associated coronavirus (SARS-CoV), a large (3×109) immunized human antibody library was constructed from peripheral blood mononuclear cells from six SARS convalescent patients. A single chain variable fragment antibody (N18) with high affinity against N protein of SARS-CoV was isolated. Sequence analysis revealed that the VL gene was composed of VL3h
The climate, substrate, and marine hydrodynamics of Jiangsu, China, tidal flats are suitable for ... more The climate, substrate, and marine hydrodynamics of Jiangsu, China, tidal flats are suitable for the growth of Spartina alterniflora. Out of 954km coastline, a section of 410km is protected by this plant, with a maximum width over 4km. It functions as a new pioneer stage in plant succession, as a major coastal association, profoundly affecting the coastal environment. Field studies
Purpose To test the following hypotheses in a murine model of pancreatic cancer: (a) Vaccination ... more Purpose To test the following hypotheses in a murine model of pancreatic cancer: (a) Vaccination with antigen-loaded iron-labeled dendritic cells reduces T2-weighted signal intensity at magnetic resonance (MR) imaging within peripheral draining lymph nodes ( LN lymph node s) and (b) such signal intensity reductions are associated with tumor size changes after dendritic cell vaccination. Materials and Methods The institutional animal care and use committee approved this study. Panc02 cells were implanted into the flanks of 27 C57BL/6 mice bilaterally. After tumors reached 10 mm, cell viability was evaluated, and iron-labeled dendritic cell vaccines were injected into the left hind footpad. The mice were randomly separated into the following three groups (n = 9 in each): Group 1 was injected with 1 million iron-labeled dendritic cells; group 2, with 2 million cells; and control mice, with 200 mL of phosphate-buffered saline. T1- and T2-weighted MR imaging of labeled dendritic cell mig...
Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine, Jan 24, 2014
Magnetization transfer (MT) MRI can be effective for the diagnosis of a broad range of fibrotic d... more Magnetization transfer (MT) MRI can be effective for the diagnosis of a broad range of fibrotic diseases, including liver fibrosis. However, respiratory motion, a major source of artifacts in thoracic and abdominal MR imaging, can obscure important anatomic structures, making diagnosis difficult. In this study, we explored the potential to combine free-breathing (FB) respiratory self-gating (RSG) methods with MT saturation for FB MT ratio (MTR) measurements of abdominal organs. A respiratory self-gated multiple-gradient recalled echo sequence with MT presaturation (RSG-MT GRE) was developed and applied in a series of seven normal volunteers. We compared the MTR values of liver, pancreas, kidney, spleen, and posterior paraspinal muscle measured using our RSG-MT GRE sequence and a conventional MT GRE sequence. RSG consistently reduced motion artifacts within MT-weighted images acquired during FB, improved the accuracy of FB MTR measurements, and produced comparable MTRs to breath-hold...
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Papers by Zhuoli Zhang