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2.
Br J Nutr ; 126(8): 1140-1148, 2021 10 28.
Article in English | MEDLINE | ID: mdl-33526155

ABSTRACT

The present study was undertaken to evaluate the influence of rumen-protected folic acid (RPFA) on slaughter performance, visceral organ and gastrointestinal tract coefficients, and meat quality in lambs. Sixty-six lambs from 120 Hu ewes were selected based on body weight and maternal diets and then assigned to six groups using a randomised block experimental design in a 3 × 2 factorial arrangement. The first factor was folic acid (FA) as RPFA in the maternal diet (0 mg/kg (M0F), 16 mg/kg (M16F) or 32 mg/kg (M32F) on DM basis). The second factor was FA in the lambs' diet from weaning until slaughter (0 mg/kg (OC) or 4·0 mg/kg (OF)). The results indicated that the addition of 16 mg/kg FA to the maternal diet increased pre-slaughter weight (PSW), dressing and meat percentage, the reticulum and omasum coefficients, length of the jejunum and ileum, tail fat and perirenal fat coefficient and a* value of the meat colour. The addition of RPFA to the lambs' diet increased PSW, dressing and meat percentage, eye muscle area, abomasum weight, weight and length of the small intestine, but reduced the coefficients of tail fat. An M × O interaction was observed for the weights of heart, lungs, rumen and total stomach, weight and coefficient of omental fat and the girth rib value. Collectively, RPFA in the maternal and lambs' diet improved slaughter performance and meat quality by stimulating the morphological development of the gastrointestinal tract and the distribution of fat in the body.


Subject(s)
Animal Nutritional Physiological Phenomena , Dietary Supplements , Folic Acid/administration & dosage , Red Meat , Rumen , Animal Feed/analysis , Animals , Diet/veterinary , Female , Maternal Nutritional Physiological Phenomena , Sheep , Sheep, Domestic , Weaning
3.
Zhonghua Shao Shang Za Zhi ; 36(6): 426-432, 2020 Jun 20.
Article in Chinese | MEDLINE | ID: mdl-32594700

ABSTRACT

Objective: To explore the effect of high-voltage electrical burn on platelet function and rheological behavior in rats and the interventive effect of Xuebijing. Methods: A total of 280 Sprague Dawley rats of clean grade (aged 8-10 weeks, male and female unlimited) were divided into sham injury group, simple electrical burn group, electrical burn+ saline group, and electrical burn+ Xuebijing group according to the random number table, with 70 rats in each group. Rats in sham injury group were not conducted with electrical current to cause sham injury. Rats in the other three groups were given electrical current with output voltage of 2 kV and current intensity of (1.92 ± 0.24) A for 3 s, which caused high-voltage electrical burn wounds, each with an area of 1 cm×1 cm distributed in the left forelimb at the current inlet and the right hindlimb at the current outlet respectively. Rats in sham injury group and simple electrical burn group were not treated after injury. At post injury minute 2 and on post injury day (PID) 1, 2, 3, 4, 5, and 6, rats in electrical burn+ saline group and electrical burn+ Xuebijing group were intraperitoneally injected with 6 mL/kg saline and 6 mL/kg Xuebijing, respectively. Survival conditions of rats were recorded during the experiment. At 15 min before injury and at post injury hour (PIH) 1, 8, 24, 48, 72, and on PID 7, 10 rats in each group were respectively selected according to the random number table to sacrifice after collection of 5 mL blood under the direct vision of heart. Blood in the volume of 0.05 mL from each rat was taken to make blood smear, and platelet aggregation number was counted under 400 fold field of view using multiple projection microscope. The remaining blood samples were centrifuged to collect supernatant, and the content of platelet-derived growth factor (PDGF), thrombopoietin (TPO), and platelet activating factor (PAF) was detected by enzyme-linked immunosorbent assay. Data were statistically analyzed with analysis of variance for factorial design and Student-Newman-Keuls method. Results: All rats in sham injury group and simple electrical burn group survived during the experiment. One rat in electrical burn+ saline group died on PID 6, and one rat on PID 5 and one rat on PID 6 died in electrical burn+ Xuebijing group. The levels of all indexes among the 4 groups were close at 15 min before injury. The serum content of PDGF, TPO, and PAF and platelet aggregation number of rats in the three electrical burn groups at all time points after injury were higher or more than those in sham injury group, and the first three indexes reached the peak at PIH 8. The serum platelet aggregation number of rats in simple electrical burn group reached the peak at PIH 48, and that in electrical burn+ saline group and electrical burn+ Xuebijing group reached the peak at PIH 72. Among them, the serum content of PDGF of rats in electrical burn+ Xuebijing group at PIH 48, 72 and on PID 7 ((12.8±4.0), (11.6±4.4), (11.0±3.6) ng/mL, respectively) was close to that in sham injury group ((10.4±2.0), (10.4±2.5), (9.8±3.3) ng/mL, respectively, P>0.05). The serum content of TPO of rats in electrical burn+ Xuebijing group at PIH 24, 72 and on PID 7 ((200±52), (192±36), (193±32) ng/mL, respectively) was close to that in sham injury group ((182±30) , (184±41), (183±33) ng/mL, respectively, P>0.05). The serum content of PDGF, TPO, and PAF and platelet aggregation number of rats in electrical burn+ Xuebijing group at every time point after injury was generally lower or less than that in electrical burn+ saline group and simple electrical burn group. Conclusions: Application of Xuebijing treatment after high-voltage electrical burn can decrease the content of PDGF, TPO, and PAF in the serum and reduce the number of platelet aggregation, thereby inhibit platelet activation and improve platelet rheology.


Subject(s)
Burns, Electric , Animals , Drugs, Chinese Herbal , Female , Male , Platelet Aggregation , Rats , Rats, Sprague-Dawley
4.
Eur Rev Med Pharmacol Sci ; 24(7): 3492-3500, 2020 04.
Article in English | MEDLINE | ID: mdl-32329822

ABSTRACT

OBJECTIVE: Bone marrow mesenchymal stem cells (BMSCs) promote bone tissue repair. MiR-1 regulates myogenic and osteogenic differentiation of human adipose tissue stem cells. However, miR-1's effect on BMSCs osteogenesis is unclear. MATERIALS AND METHODS: Rat BMSCs were isolated and divided into control group, miR-1 group, and si-miR-1 group respectively transfected with miR-1 plasmid and miR-1 siRNA followed by analysis of cell proliferation by MTT assay and Caspase 3 activity. The expression of osteogenic genes Runx2 and OPN was measured by Real Time-PCR. Healthy male Sprague-Dawley rats were separated into fracture group, NC group, and si-miR-1 group followed by analysis of bone mineral density, miR-1 level by Real Time-PCR, type I collagen, and BMP-2 by enzyme-linked immunosorbent assay (ELISA), and TLR1 expression by Western blot. RESULTS: Transfection of miR-1 siRNA into BMSCs significantly downregulated miR-1 expression, promoted BMSCs cell proliferation, inhibited Caspase 3 activity, as well as promoted osteogenic genes Runx2 and OPN expression and decreased TLR1 expression (p<0.05). The upregulation of miR-1 expression significantly reversed the above changes. TLR1 is a target of miR-1. Downregulation of miR-1 expression in BMSCs of fractured rats significantly increased bone density and ALP activity, promoted type I collagen and BMP-2 expression, and decreased TLR1 expression (p<0.05). CONCLUSIONS: The downregulation of miR-1 promotes BMSCs osteogenic differentiation via targeting TLR1, which promotes osteogenic differentiation and bone healing.


Subject(s)
Mesenchymal Stem Cells/metabolism , MicroRNAs/genetics , Toll-Like Receptor 1/genetics , Animals , Cell Proliferation , Female , Male , MicroRNAs/metabolism , Osteogenesis/genetics , Rats , Rats, Sprague-Dawley , Toll-Like Receptor 1/metabolism
5.
Nat Mater ; 19(4): 397-404, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31844275

ABSTRACT

The ground-state properties of correlated electron systems can be extraordinarily sensitive to external stimuli, offering abundant platforms for functional materials. Using the multi-messenger combination of atomic force microscopy, cryogenic scanning near-field optical microscopy, magnetic force microscopy and ultrafast laser excitation, we demonstrate both 'writing' and 'erasing' of a metastable ferromagnetic metal phase in strained films of La2/3Ca1/3MnO3 (LCMO) with nanometre-resolved finesse. By tracking both optical conductivity and magnetism at the nanoscale, we reveal how strain-coupling underlies the dynamic growth, spontaneous nanotexture and first-order melting transition of this hidden photoinduced metal. Our first-principles calculations reveal that epitaxially engineered Jahn-Teller distortion can stabilize nearly degenerate antiferromagnetic insulator and ferromagnetic metal phases. We propose a Ginzburg-Landau description to rationalize the co-active interplay of strain, lattice distortions and magnetism nano-resolved here in strained LCMO, thus guiding future functional engineering of epitaxial oxides into the regime of phase-programmable materials.

6.
J Chem Phys ; 147(20): 204501, 2017 Nov 28.
Article in English | MEDLINE | ID: mdl-29195280

ABSTRACT

Although the existence of liquid-liquid phase transition has become more and more convincing, whether it will terminate at a critical point and what is the order parameter are still open. To explore these questions, we revisit the fluid-liquid phase transition (FLPT) in phosphorus (P) and study its phase behavior by performing extensive first-principles molecular dynamics simulations. The FLPT observed in experiments is well reproduced, and a fluid-liquid critical point (FLCP) at T = 3000 ∼ 3500 K, P = 1.5-2.0 Kbar is found. With decreasing temperature from the FLCP along the transition line, the density difference (Δρ) between two coexisting phases first increases from zero and then anomalously decreases; however, the entropy difference (ΔS) continuously increases from zero. These features suggest that an order parameter containing contributions from both the density and the entropy is needed to describe the FLPT in P, and at least at low temperatures, the entropy, instead of the density, governs the FLPT.

7.
Oncogenesis ; 6(7): e368, 2017 Jul 31.
Article in English | MEDLINE | ID: mdl-28759023

ABSTRACT

Methyl-CpG binding protein 2 (MeCP2) is involved in the carcinogenesis and progression of multiple types of cancer. However, its precise role in gastric cancer (GC) and the relevant molecular mechanism remain unknown. In the present study, we found that miR-638 levels were lower in GC tissues and GC cell lines than in adjacent normal tissues and normal gastric epithelial cell lines, respectively. Low miR-638 levels were associated with poor tumor differentiation, tumor size and lymph node metastasis. MeCP2 expression levels were higher in GC tissues than in adjacent normal tissues. It was found that miR-638 inhibited GC cell proliferation, colony formation, G1-S transition and tumor growth, and induced cell apoptosis by directly targeting MeCP2. MeCP2 promoted GC cell proliferation, colony formation and G1-S cell-cycle transition, and suppressed apoptosis. Molecular mechanistic investigations were performed using an integrated approach with a combination of microarray analysis, chromatin immunoprecipitation sequencing and a reporter gene assay. The results showed that MeCP2 bound to the methylated CpG islands of G-protein-coupled receptor kinase-interacting protein 1 (GIT1) promoter and upregulated its expression, thereby activating the MEK1/2-ERK1/2 signaling pathway and promoting GC cell proliferation. Taken together, our study demonstrates that MeCP2, a target of miR-638, facilitates GC cell proliferation and induces cell-cycle progression through activation of the MEK1/2-ERK1/2 signaling pathway by upregulating GIT1. The findings suggest that MeCP2 plays a significant role in GC progression, and may serve as a potential target for GC therapy.

8.
Nanoscale ; 9(22): 7385-7390, 2017 Jun 08.
Article in English | MEDLINE | ID: mdl-28541364

ABSTRACT

We report on a field induced domain evolutionary procedure in the anisotropic Nd-Dy-Fe-Co-B/MgO/Fe multilayers by using first-order-reversal-curves and magnetic force microscopy. Different reversal behaviors and domain sizes are found in well coupled and decoupled multilayers by changing the thickness of the spacer layer. The competition between dipolar magnetostatic energy and Zeeman energy is evaluated by in-field observation throughout nucleation and annihilation processes. In addition, lithography-patterned arrays of soft Fe disks onto a continuous Nd-Dy-Fe-Co-B hard-magnetic layer are designed. By decreasing the applied field, it is found that magnetization orientations of the Fe disk and Nd-Dy-Fe-Co-B layer are aligned parallel. In the decoupled disk, although the out-of-plane magnetization orientations are observed, the orientation of the domains in the Fe disk is random. Furthermore, it is found that a stronger anisotropy of the Nd-Dy-Fe-Co-B layer decreases the interaction length. Our results provide a new understanding of anisotropic nanocomposite magnets with long-ranged magnetic interactions.

9.
Sci Rep ; 7: 39952, 2017 01 05.
Article in English | MEDLINE | ID: mdl-28054595

ABSTRACT

The relationship between structural order and water-like anomalies in tetrahedral liquids is still open. Here, first-principle molecular dynamics are performed to study it in metastable liquid Si. It is found that in T-P phase diagram, there indeed exists a structural anomaly region, which encloses density anomaly but not diffusivity anomaly. This is consistent with that of SW Si and BKS SiO2 but different from that of SPC/E water. Two-body excess entropy anomaly can neither capture the diffusivity, structural, and density anomalies, as it can in a two-scale potential fluid. In structural anomaly region, tetrahedrality order qtetra (measuring the extent to which an atom and its four nearest neighbours adopt tetrahedral arrangement) and translational order ttrans (measuring the tendency of two atoms to adopt preferential separation) are not perfectly correlated, which is different from that in SW Si and renders it impossible to use the isotaxis line to quantify the degree of structural order needed for water-like anomalies to occur. Along the isotherm of critical temperature Tc, ttrans/qtetra is approximately linear with pressure. With decreasing pressure along the isotherm below Tc, ttrans/qtetra departs downward from the line, while it is the opposite case above Tc.

10.
Oncol Rep ; 34(5): 2289-95, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26323510

ABSTRACT

Dendritic cells (DCs) as 'professional' antigen-presenting cells (APCs) initiate and regulate immune responses to various antigens. DC-based vaccines have become a promising modality in cancer immunotherapy. Cytokeratin 19 (CK19) protein is expressed at high levels in lung cancer and many other tumor cells, suggesting CK19 as a potential tumor­specific target for cancer immune therapy. We constructed a recombinant adenoviral vector containing the CK19 gene (rAd-CK19). DCs transfected with rAd-CK19 were used to vaccinate C57BL/6 mice bearing xenografts derived from Lewis lung carcinoma (LLC) cells. The transfected DCs gave rise to potent CK19-specific cytotoxic T lymphocytes (CTLs) capable of lysing LLC cells. Mice immunized with the rAd­CK19-DCs exhibited significantly attenuated tumor growth (including tumor volume and weight) when compared to the tumor growth of mice immunized with rAd-c DCs or DCs during the 24-day observation period (P<0.05). The results revealed that the mice vaccinated with the rAd-CK19-DCs exhibited a potent protective and therapeutic antitumor immunity to LLC cells in the subcutaneous model along with an inhibitive effect on tumor growth compared to the mice vaccinated with the rAd-c DCs or DCs alone. The present study proposes a meaningful mode of action utilizing rAd-CK19 DCs in lung cancer immunotherapy.


Subject(s)
Cancer Vaccines/immunology , Carcinoma, Lewis Lung/therapy , Dendritic Cells/transplantation , Keratin-19/immunology , Adenoviridae/genetics , Animals , Antibody-Dependent Cell Cytotoxicity , Cancer Vaccines/genetics , Carcinoma, Lewis Lung/immunology , Cell Line, Tumor , Cell Proliferation , Dendritic Cells/immunology , Gene Expression , Genetic Vectors , HEK293 Cells , Humans , Keratin-19/biosynthesis , Keratin-19/genetics , Mice, Inbred C57BL , Neoplasm Transplantation , T-Lymphocytes, Cytotoxic/immunology , Transduction, Genetic
11.
Sci Rep ; 5: 9361, 2015 Mar 23.
Article in English | MEDLINE | ID: mdl-25797135

ABSTRACT

Single magnetic atoms absorbed on an atomically thin layer represent the ultimate limit of bit miniaturization for data storage. To approach the limit, a critical step is to find an appropriate material system with high chemical stability and large magnetic anisotropic energy. Here, on the basis of first-principles calculations and the spin-orbit coupling theory, it is elucidated that the transition-metal Mn and Fe atoms absorbed on disulfur vacancies of MoS2 monolayers are very promising candidates. It is analysed that these absorption systems are of not only high chemical stabilities but also much enhanced magnetic anisotropies and particularly the easy magnetization axis is changed from the in-plane one for Mn to the out-of-plane one for Fe by a symmetry-lowering Jahn-Teller distortion. The results point out a promising direction to achieve the ultimate goal of single adatomic magnets with utilizing the defective atomically thin layers.


Subject(s)
Disulfides/chemistry , Iron/chemistry , Magnetics/instrumentation , Manganese/chemistry , Models, Chemical , Molybdenum/chemistry , Anisotropy , Computer Simulation , Information Storage and Retrieval , Quantum Theory
12.
Cell Mol Biol (Noisy-le-grand) ; Suppl 59: OL1876-81, 2013 Nov 03.
Article in English | MEDLINE | ID: mdl-24199952

ABSTRACT

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide and currently represents the leading cause of death amongst cirrhotic patients, but the mechanisms remain unknown. In this experiment, we investigated the expression of Methyl CpG-binding protein 2 (MeCP2) in HCC, the effect of MeCP2 on the proliferation of human HCC HepG2 cells, and the activation of mitogen-activated protein kinases (MAPKs) signaling pathways. The results showed that MeCP2 expression levels was higher in human HCC tissue than normal hepatocellular tissue, and MeCP2 siRNA reduced the proliferation of HCC HepG2 cells by decreasing cell activity and cell division in vitro. After MeCP2 siRNA treatment, the proportion of G1/G0 phase cells increased, but the proportion of S and G2/M phase cells decreased, indicative of G1/G0 cell cycle arrest. Furthermore, the proportions of early and late apoptosis in HCC HepG2 cells were enhanced after MeCP2 siRNA treatment. It was also found that activation of extracellular signal-regulated protein kinase (ERK) and p38 signaling pathways were involved in the proliferation of HepG2 cells. After MeCP2 siRNA treatment, p-ERK1/2 levels decreased, but p-p38 levels increased. Our findings demonstrated that MeCP2 promoted the proliferation of human HCC HepG2 cells with activation of ERK1/2 signaling pathways, suggesting a novel mechanism for pharmacological study of treatment for human HCC.


Subject(s)
Carcinoma, Hepatocellular/enzymology , Carcinoma, Hepatocellular/pathology , Extracellular Signal-Regulated MAP Kinases/metabolism , Liver Neoplasms/enzymology , Liver Neoplasms/pathology , Methyl-CpG-Binding Protein 2/metabolism , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors , Apoptosis , Carcinoma, Hepatocellular/genetics , Cell Proliferation , Enzyme Activation , Gene Expression Regulation, Neoplastic , Gene Silencing , Hep G2 Cells , Humans , Liver Neoplasms/genetics , Methyl-CpG-Binding Protein 2/genetics , Phosphorylation , p38 Mitogen-Activated Protein Kinases/metabolism
13.
Bioorg Med Chem ; 20(24): 6929-39, 2012 Dec 15.
Article in English | MEDLINE | ID: mdl-23159039

ABSTRACT

A major drawback of internalizing monoclonal antibodies (mAbs) radioiodinated with direct electrophilic approaches is that tumor retention of radioactivity is compromised by the rapid washout of iodo-tyrosine, the primary labeled catabolite for mAbs labeled via this strategy. In our continuing efforts to develop more versatile residualizing labels that could overcome this problem, we have designed SIB-DOTA, a prosthetic labeling template that combines the features of the prototypical, dehalogenation-resistant N-succinimidyl 3-iodobenzoate (SIB) with DOTA, a useful macrocyclic chelator for labeling with radiometals. Herein we describe the synthesis of the unlabeled standard of this prosthetic moiety, its protected tin precursor, and radioiodinated SIB-DOTA. An anti-EGFRvIII-reactive mAb, L8A4 was radiolabeled with [(131)I]SIB-DOTA in 27.1±6.2% (n=2) conjugation yields and its targeting properties to the same mAb labeled with [(125)I]SGMIB both in vitro and in vivo using U87MG·ΔEGFR cells and xenografts were compared. In vitro paired-label internalization assays showed that the intracellular radioactivity from [(131)I]SIB-DOTA-L8A4 was 21.4±0.5% and 26.2±1.1% of initially bound radioactivity at 16 and 24h, respectively. In comparison, these values for [(125)I]SGMIB-L8A4 were 16.7±0.5% and 14.9±1.1%. Similarly, the SIB-DOTA prosthetic group provided better tumor targeting in vivo than SGMIB over 8 d period. These results suggest that SIB-DOTA warrants further evaluation as a residualizing agent for labeling internalizing mAbs including those targeted to EGFRvIII.


Subject(s)
Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/pharmacokinetics , Heterocyclic Compounds, 1-Ring/chemistry , Immunotoxins/chemistry , Immunotoxins/pharmacokinetics , Iodobenzoates/chemistry , Radiopharmaceuticals/chemical synthesis , Animals , Antibodies, Monoclonal/immunology , Cell Line, Tumor , ErbB Receptors/immunology , Glioblastoma/immunology , Glioblastoma/metabolism , Heterocyclic Compounds, 1-Ring/chemical synthesis , Heterocyclic Compounds, 1-Ring/pharmacokinetics , Humans , Iodine Radioisotopes/chemistry , Iodine Radioisotopes/pharmacokinetics , Iodobenzoates/chemical synthesis , Iodobenzoates/pharmacokinetics , Isotope Labeling/methods , Mice , Mice, Inbred BALB C , Organometallic Compounds/chemistry , Radiopharmaceuticals/chemistry , Radiopharmaceuticals/immunology , Radiopharmaceuticals/pharmacokinetics , Tin/chemistry , Tissue Distribution
14.
Bioinformatics ; 27(21): 3050-5, 2011 Nov 01.
Article in English | MEDLINE | ID: mdl-21908541

ABSTRACT

MOTIVATION: The area under the receiver operating characteristic (ROC) curve (AUC), long regarded as a 'golden' measure for the predictiveness of a continuous score, has propelled the need to develop AUC-based predictors. However, the AUC-based ensemble methods are rather scant, largely due to the fact that the associated objective function is neither continuous nor concave. Indeed, there is no reliable numerical algorithm identifying optimal combination of a set of biomarkers to maximize the AUC, especially when the number of biomarkers is large. RESULTS: We have proposed a novel AUC-based statistical ensemble methods for combining multiple biomarkers to differentiate a binary response of interest. Specifically, we propose to replace the non-continuous and non-convex AUC objective function by a convex surrogate loss function, whose minimizer can be efficiently identified. With the established framework, the lasso and other regularization techniques enable feature selections. Extensive simulations have demonstrated the superiority of the new methods to the existing methods. The proposal has been applied to a gene expression dataset to construct gene expression scores to differentiate elderly women with low bone mineral density (BMD) and those with normal BMD. The AUCs of the resulting scores in the independent test dataset has been satisfactory. CONCLUSION: Aiming for directly maximizing AUC, the proposed AUC-based ensemble method provides an efficient means of generating a stable combination of multiple biomarkers, which is especially useful under the high-dimensional settings. CONTACT: lutian@stanford.edu. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Subject(s)
Bone Density/genetics , Aged , Algorithms , Area Under Curve , Biomarkers/metabolism , Female , Gene Expression , Humans , ROC Curve
15.
Article in English | MEDLINE | ID: mdl-19162608

ABSTRACT

Magnetic Resonance Elastography (MRE) is a phase contrast imaging technique to quantitatively measure the elasticity of tissues. Typically, the oscillating driver is placed on the surface of objects to generate shear waves. When it is applied to detect tumors in deep location, the depth penetration of the wave is limited by attenuation and the biopsy procedure has to be performed separately. In this study, we describe a method using biopsy needle as the MRE driver to produce shear waves in tissues. We made comparison between the MRE acquisitions obtained with biopsy needle and surface drivers. Because the well-defined propagation wave pattern reduces the error in wavelength calculation, the acquisitions of biopsy needle driver shows better homogeneity in stiffness map. We also performed the experiment with the biopsy needle for in vivo tumor detection in rabbits. This study demonstrates that the biopsy needle driver is more effective than the surface driver for accurately measuring the stiffness and location of the tumor.


Subject(s)
Biopsy, Needle/instrumentation , Elasticity Imaging Techniques/instrumentation , Image Enhancement/instrumentation , Liver Neoplasms/diagnosis , Needles , Animals , Elasticity Imaging Techniques/methods , Equipment Design , Equipment Failure Analysis , Female , Humans , Rabbits , Reproducibility of Results , Sensitivity and Specificity
16.
Article in English | MEDLINE | ID: mdl-19163092

ABSTRACT

Olfactory bulb (OB) is one of the most developed systems in rodent models with complex neuronal organization and anatomical structures. MR diffusion tensor imaging (DTI) is a non-invasive technique to probe tissue microstructures by examining the diffusion characteristics of water molecules. This paper presents how different OB layers can be identified and quantitatively characterized by micro-DTI using a specially constructed micro-imaging radio frequency (RF) coil. High spatial resolution and high signal to noise ratio (SNR) DTI images of ex vivo rat OBs were obtained. Distinct contrasts were observed between various olfactory bulb layers in trace map, fractional anisotropy (FA) map and FA color map, all in consistency with the known OB neuroanatomy. These experimental results demonstrate the utility of micro-DTI in investigation of complex OB organization.


Subject(s)
Diffusion Magnetic Resonance Imaging/methods , Image Processing, Computer-Assisted/methods , Olfactory Bulb/anatomy & histology , Animals , Anisotropy , Female , Models, Animal , Rats , Rats, Sprague-Dawley , Software
17.
Article in English | MEDLINE | ID: mdl-18002389

ABSTRACT

Magnetic Resonance Elastography (MRE) is a phase contrast imaging technique to quantitatively measure the elasticity of tissues. Typically, an oscillating driver is placed on the surface to generate the shear waves. The depth penetration of the wave is limited by attenuation and the biopsy procedure has to be done separately. In this study, we use a biopsy needle as the driver to detect the 15% porcine gel inclusion in a 10% porcine gel phantom which simulates a tumor in tissues. We also perform the experiment with the biopsy needle for in-vivo tumor detection in rabbits. It is shown that the biopsy needle driver can accurately measure the stiffness and location of the tumor.


Subject(s)
Magnetic Resonance Imaging/instrumentation , Neoplasms/diagnosis , Neoplasms/pathology , Animals , Biopsy , Biopsy, Needle , Elasticity , Equipment Design , Extremities , Female , Image Enhancement , Magnetic Resonance Imaging/methods , Models, Statistical , Phantoms, Imaging , Rabbits , Stress, Mechanical , Swine
18.
J Anim Sci ; 85(12): 3340-7, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17709770

ABSTRACT

This study investigated the effects of supplementation of various sources of Met and Lys on nutrient digestion, N utilization, and duodenal AA flows in growing goats. Four 4-mo-old Liuyang Black wether goats were used in a 4 x 4 Latin square experiment and were assigned to 4 dietary treatments: (1) control, (2) control + lipid-coated Met-Zn chelate and Lys-Mn chelate (PML), (3) control + Met-Zn chelate and Lys-Mn chelate (CML), and (4) control + dl-Met, l-Lys-HCl, ZnSO(4).7H(2)O, and MnSO(4).H(2)O (FML). Compared with control, PML reduced (P < 0.05) ruminal NH(3) concentration, urinary N excretion, and plasma urea N concentration and increased (P < 0.05) the activity of ruminal endo-1,4-beta-d-glucanase and beta-glucosidase, the duodenal flow of N, N retention (g/d as well as % of absorbed N), the duodenal flows of Met, Lys, His, Val, and total essential AA, and plasma concentrations of Lys, Val, Phe, and total essential AA. Supplementing Zn-Met and Mn-Lys chelates had similar (P > 0.05) but lesser effects on these measures compared with PML, and the effects on most of the measures were not statistically significant (P > 0.05) when compared with control. Supplementing free-form Met and Lys had no effects compared with control (P > 0.05). The results indicate that lipid coating and chelating of AA provide a protection, and to a lesser extent by only chelating, of the AA from microbial degradation in the rumen and possibly has effects on rumen fermentation, which increases MP supply. This technology could improve productive performance and be of potential benefit to ruminant production if cost-effective products are developed.


Subject(s)
Chelating Agents/pharmacology , Dietary Proteins/pharmacology , Digestion/drug effects , Duodenum/metabolism , Goats/metabolism , Nitrogen/metabolism , Rumen , Ammonia/analysis , Ammonia/metabolism , Animals , Blood Urea Nitrogen , Dietary Proteins/metabolism , Digestion/physiology , Fermentation , Goats/growth & development , Lysine/metabolism , Lysine/pharmacology , Male , Methionine/metabolism , Methionine/pharmacology , Random Allocation , Rumen/metabolism , Rumen/microbiology
19.
J Nucl Med ; 42(10): 1508-15, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11585865

ABSTRACT

UNLABELLED: In vitro and in vivo studies in human glioma models suggest that the antitenascin monoclonal antibody 81C6 labeled with the 7.2-h-half-life alpha-particle emitter (211)At might be a valuable endoradiotherapeutic agent for the treatment of brain tumors. The purpose of this study was to develop methods for the production of high levels of (211)At and the radiosynthesis of clinically useful amounts of (211)At-labeled human/mouse chimeric 81C6 antibody. METHODS: (211)At was produced through the (209)Bi(alpha, 2n)(211)At reaction using an internal target system and purified by a dry distillation process. Antibody labeling was accomplished by first synthesizing N-succinimidyl 3-[(211)At]astatobenzoate from the corresponding tri-n-butyl tin precursor and reacting it with the antibody in pH 8.5 borate buffer. Quality control procedures consisted of methanol precipitation, size-exclusion high-performance liquid chromatography (HPLC), and pyrogen and sterility assays, as well as determination of the immunoreactive fraction by a rapid procedure using a recombinant tenascin fragment coupled to magnetic beads. RESULTS: A total of 16 antibody labeling runs were performed. Using beam currents of 50-60 microA alpha-particles and irradiation times of 1.5-4.5 h, the mean (211)At production yield was 27.75 +/- 2.59 MBq/microA.h, and the maximum level of (211)At produced was 6.59 GBq after a 4-h irradiation at 55 microA. The decay-corrected distillation yield was 67% +/- 16%. The yield for the coupling of the (211)At-labeled active ester to the antibody was 76% +/- 8%. The fraction of (211)At activity that eluted with a retention time corresponding to intact IgG on HPLC was 96.0% +/- 2.5%. All preparations had a pyrogen level of <0.125 EU/mL and were determined to be sterile. The mean immunoreactive fraction for these 16 preparations was 83.3% +/- 5.3%. Radiolysis did not interfere with labeling chemistry or the quality of the labeled antibody product. CONCLUSION: These results show that it is feasible to produce clinically relevant activities of (211)At-labeled antibodies and have permitted the initiation of a phase I trial of (211)At-labeled chimeric 81C6 administered directly into the tumor resection cavities of brain tumor patients.


Subject(s)
Antibodies, Monoclonal , Astatine , Immunoconjugates , Isotope Labeling , Alpha Particles , Immunoconjugates/therapeutic use , Radioimmunotherapy , Recombinant Fusion Proteins/immunology , Tenascin/immunology
20.
J Nanosci Nanotechnol ; 1(2): 153-8, 2001 Jun.
Article in English | MEDLINE | ID: mdl-12914046

ABSTRACT

Carbon- and boron-oxide-encapsulated iron nanocapsules have been synthesized by arc discharge in methane (CH4) and diborane (B2H6) atmospheres respectively. The characterization and magnetic properties of carbon- and boron-oxide-encapsulated iron nanocapsules [abbreviated as Fe(C) and Fe(B) respectively] were investigated and compared. The structure of the Fe(B) nanocapsules is different from that of the Fe(C) nanocapsules. The Fe(C) nanocapsules consist of a crystalline graphite shell and a core of alpha-Fe and/or Fe3C. The Fe(B) nanocapsules consist of an amorphous boron-oxide layer and a core of Fe(B) solid solution, alpha-Fe, gamma-Fe, FeB, and/or Fe3B phases. The saturation magnetizations of both the Fe(C) and the Fe(B) nanocapsules below 300 K decrease monotonically with increasing temperature. The coercivities of the Fe(C) and Fe(B) nanocapsules are almost 2 orders of magnitude higher than that of bulk Fe. The temperature dependence of magnetization at high temperatures indicates the existence of some phase transformations.


Subject(s)
Boron Compounds/chemistry , Carbon/chemistry , Drug Compounding/methods , Iron/chemistry , Magnetics , Nanotechnology/methods , Borohydrides/chemistry , Boron Compounds/chemical synthesis , Boron Compounds/isolation & purification , Carbon/isolation & purification , Iron/isolation & purification , Macromolecular Substances , Methane/chemistry , Microscopy, Electron , Microspheres , Molecular Conformation , Particle Size , Temperature , X-Ray Diffraction
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