Publications by authors named "Xi G"

Purpose: Brain stem gliomas account for 20% of childhood brain tumors. Presently, there is no effective treatment for these tumors, and the prognosis remains poor. One reason for this is that chemotherapeutic drugs cannot cross the blood-brain barrier.

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Background: Previous studies have shown that Epstein-Barr virus (EBV)-encoded latent membrane protein 1 (LMP1) is closely associated with the occurrence and development of nasopharyngeal carcinoma, and can be used as a tumor marker in screening for the disease. Here we report a new methodology based on highly specific and sensitive surface-enhanced Raman scattering (SERS) technology to detect LMP1 in nasopharyngeal tissue sections directly with no need of tedious procedures as with conventional immunohistochemistry methods.

Methods: LMP1-functionalized 4-mercaptobenzoic acid (4-MBA)-labeled Au/Ag core-shell bimetallic nanoparticles were prepared first and then applied for analyzing LMP1 in formalin-fixed paraffin-embedded nasopharyngeal tissue sections obtained from 34 cancer patients and 20 healthy controls.

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The L-theanine was tested using confocal Raman microscopy. Obvious Raman bands were showed in the range of 250 -1 700 and 2 800-3 000 cm(-1). The Raman bands were assigned with a preliminary analysis and the characteristic vibrational modes were gained in different range of wave numbers.

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Objective: To provide scientific cue for the use of Halenia elliptica.

Methods: The crude polysaccharide was extracted from Halenia elliptica with hot water and precipitated by ethanol. The crude polysaccharide has been eliminated protein and fractionated by acidic ethanol.

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It is generally accepted that cognitive processes, such as learning and memory, are affected in depression. The present study used a rat model of depression, chronic unpredictable mild stress (CUMS), to determine whether hippocampal volume and neurochemical changes were involved in learning and memory alterations. A further aim was to determine whether these effects could be ameliorated by escitalopram treatment, as assessed with the non-invasive techniques of structural magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS).

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IGF-I-stimulated sarcoma viral oncogene (Src) activation during hyperglycemia is required for propagating downstream signaling. The aim of the current study was to determine the mechanism by which hyperglycemia enhances IGF-I-stimulated Src activation and the role of NADPH oxidase 4 (Nox4) and protein kinase C ζ (PKCζ) in mediating this response in vascular smooth muscle cells (VSMCs). Nox4 expression was analyzed in VSMCs exposed to hyperglycemia.

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Autophagy occurs in the brain after intracerebral hemorrhage (ICH) and thrombin contributes to ICH-induced brain injury and cell death. In this study, we investigated whether thrombin may activate autophagy (in vivo and in cultured astrocytes) and its potential role in ICH. Autophagy was examined using electron microscopy, conversion of light chain 3(LC3) from the LC3-I form to LC3-II, cathepsin D Western blotting and monodansylcadaverine (MDC) staining to detect autophagic vacuoles.

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Background And Purpose: Brain iron overload plays a detrimental role in brain injury after intracerebral hemorrhage (ICH). A recent study found that minocycline acts as an iron chelator and reduces iron-induced neuronal death in vitro. The present study investigated if minocycline reduces iron overload after ICH and iron-induced brain injury in vivo.

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A comprehensive two-dimensional system coupling ultra-performance liquid chromatography (UPLC) and ion mobility-mass spectrometry (IM-MS) has been applied for the separation and analysis of hydroxylated polybrominated diphenyl ethers (OH-PBDEs). A complex mixture containing 23 OH-PBDE congeners ranging from hydroxylated monobromodiphenyl ether (OH-monoBDE) to hydroxylated octabromodiphenyl ether (OH-octaBDE) was satisfactorily separated within 16 min of analysis time. The first-dimensional reversed-phase UPLC was performed on a sub-2 μm BEH C(18) chromatographic column using acetonitrile-water gradient elution program with a flow rate ramp.

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The effect of subarachnoid hemoglobin on neuroglial cells contributing to early brain injury is unclear. Several intracerebral hemorrhage studies indicated that pathological iron deposition in the brain contributes to secondary brain injury. Therefore, the purpose of this study was to investigate the relationship between iron and neuroglial cell changes following SAH, and examine the effect of deferoxamine (DFX).

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Background And Purpose: Treatment with the iron chelator, deferoxamine mesylate (DFO), improves neurological recovery in animal models of intracerebral hemorrhage (ICH). We aimed to evaluate the feasibility, safety, and tolerability of varying dose-tiers of DFO in patients with spontaneous ICH, and to determine the maximum tolerated dose to be adopted in future efficacy studies.

Methods: This was a multicenter, phase-I, dose-finding study using the Continual Reassessment Method.

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Interstitial chemotherapeutic drug infusion can bypass the blood-brain barrier, and provide high regional drug concentrations without systemic exposure. However, toxicity and efficacy for drugs administered via interstitial continuous (i.c.

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A surface-enhanced Raman spectroscopy (SERS) method combined with multivariate analysis was developed for non-invasive gastric cancer detection. SERS measurements were performed on two groups of blood plasma samples: one group from 32 gastric patients and the other group from 33 healthy volunteers. Tentative assignments of the Raman bands in the measured SERS spectra suggest interesting cancer-specific biomolecular changes, including an increase in the relative amounts of nucleic acid, collagen, phospholipids and phenylalanine and a decrease in the percentage of amino acids and saccharide in the blood plasma of gastric cancer patients as compared with those of healthy subjects.

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IGF-I plays an important role in smooth muscle cell proliferation and migration. In vascular smooth muscle cells cultured in 25 mm glucose, IGF-I stimulated a significant increase in Src homology 2 domain containing protein tyrosine phosphatase substrate-1 (SHPS-1) phosphorylation compared with 5 mm glucose and this increase was required for smooth muscle cell proliferation. A proteome-wide screen revealed that carboxyl-terminal SRC kinase homologous kinase (CTK) bound directly to phosphotyrosines in the SHPS-1 cytoplasmic domain.

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Studies have shown that progesterone reduces brain injury, whereas testosterone increases lesion size after ischemic stroke. This study examined the effects of progesterone and testosterone on intracerebral hemorrhage (ICH)-induced brain injury. Male Sprague-Dawley rats received an injection of 100 μL autologous whole blood into the right basal ganglia.

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Tamoxifen is a selective estrogen receptor modulator. In this study we investigated whether or not tamoxifen reduces intracerebral hemorrhage (ICH)-induced brain injury in rats. In all experiments, adult male Sprague-Dawley rats received an injection of 100 μL autologous whole blood into the right basal ganglia.

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Pretreatment with a low dose of thrombin attenuated brain injury after intracerebral hemorrhage (ICH) or cerebral ischemia. This phenomenon has been called thrombin preconditioning (TPC). The current study investigated whether or not TPC reduces neuronal death induced by iron in cultured neurons.

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Cerebral preconditioning with a low dose of thrombin attenuates brain edema induced by intracerebral hemorrhage (ICH), a large dose of thrombin or iron. This study examined whether or not thrombin preconditioning (TPC) reduces neuronal death and brain atrophy caused by iron. The right hippocampus of rats was pretreated with or without thrombin, and iron was then injected into the same location 3 days later.

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Cardiac dysfunction can occur after intracerebral hemorrhage (ICH). This study examined the expression of heat shock proteins (HSPs) in the heart after ICH in aged rats and whether deferoxamine (DFX), an iron chelator, affects HSP expression. Male Fischer 344 rats (18 months old) received an injection of 100 μl autologous blood into the right caudate, whereas sham-operated rats had a needle insertion.

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This study investigated whether deferoxamine (DFX), an iron chelator, reduces cavity size after ICH in aged rats. Aged male Fischer rats (18 months old) had an intracaudate injection of 100 μL autologous blood and were treated with DFX or vehicle. Rats were euthanized at day 56 and brains were perfused for histology and immunohistochemistry.

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The purpose of this study was to examine the expression of hemoglobin (Hb) in the brain after intracerebral hemorrhage (ICH) and the effects of hemin and iron on neuronal Hb. For the in vivo studies, male Sprague-Dawley rats received either a sham operation or an ICH. The rats were killed 1, 4, 24 or 72 h later, and brains were used for real-time polymerase chain reaction (PCR) and immunohistochemistry.

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Cerebral iron overload causes brain injury after intracerebral hemorrhage (ICH) in rats and pigs. The current study examined whether an iron chelator, deferoxamine, can reduce ICH-induced DNA damage in pigs. Pigs received an injection of autologous blood into the right frontal lobe.

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Intracerebral hemorrhage (ICH)-induced brain injury is less in female than in male rats, and estrogen can reduce such injury in males. Myocardial injury occurs after ischemic and hemorrhagic stroke, and the current study investigated the effects of gender on heart injury after ICH in rats. In the first part of the study, male and female rats had an intracerebral injection of 100 μL autologous blood, and sham-operated rats had a needle insertion.

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Intracerebral hemorrhage (ICH) causes severe brain injury in aged rats. Autophagy occurs in the brain after ICH, and the present study examined the effects of aging on autophagy after ICH. Aged (18-22-month) and young (4-6-month) male Fischer rats received an intracerebral injection of 100-μL autologous whole blood.

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