PubMed Health⌕ Search

Biomedical subjects

Hong Sun

Publications and source records attributed to Hong Sun.

At least 37 records · Page 2Linked to original sources
PubMed2006

[Diffusion tensor imaging of the normal-appearing brain tissue in relapsing-remitting multiple sclerosis].

OBJECTIVE: To investigate whether normal-appearing brain tissue (NABT) on conventional MRI has occult damage in patients with relapsing-remitting multiple sclerosis (RRMS) by using diffusion tensor imaging (DTI) histogram analysis, and to determine the correlations between DTI histogram-derived measures of the NABT and expanded disability status scale (EDSS) scores, disease durations, T2WI lesion volumes and brain tissue volumes in RRMS patients. METHODS: Conventional MRI and DTI scans were performed in 24 patients with RRMS and 24 sex- and age-matched healthy controls. After segmentation of the NABT, the mean diffusivity (MD) and fractional anisotropy (FA) histograms of the NABT were created and analyzed. RESULTS: In patients with RRMS, the average MD (1.014 x 10(-3) mm2 x s(-1)) of the NABT was higher than that (0.910 x 10(-3) mm2 x s(-1)) of control subjects (t = 7.238, P < 0.001); the MD histogram peak height (8.858 per thousand) of the NABT was lower than that (0.767 per thousand) of control subjects (t = 6.161, P < 0.001); the MD histogram peak location (0.809 x 10(-3) mm2 x s(-1)) of the NABT was higher than that (0.767 x 10(-3) mm2 x s(-1)) of control subjects (t = 5.324, P < 0.001); the average FA (0.231) of the NABT was lower than that (0.254) of control subjects (t = 6.217, P < 0.001); the FA histogram peak height (4.502 per thousand) of the NABT was higher than that (4.107 per thousand) of control subjects (t = 4.198, P < 0.001); no significant difference was found in the FA histogram peak location of the NABT between these two groups (t = 1.223, P = 0.227); none of the DTI histogram-derived measures correlated with EDSS scores or disease durations (P > 0.05); the average MD and all the FA histogram-derived measures correlated with T2WI lesion volumes (P < 0.05); and the average MD, the MD histogram peak height and all the FA histogram-derived measures correlated with brain tissue volumes (P < 0.05). In healthy controls, however, only the average FA of the NABT correlated with brain tissue volumes. CONCLUSION: Patients with RRMS had occult damage in the NABT and the extent of NABT damage was related to the lesion load of brain and to the extent of brain tissue atrophy.

Adolescent↗
PubMed2006

Challenges of detecting directional selection after a bottleneck: lessons from Sorghum bicolor.

Multilocus surveys of sequence variation can be used to identify targets of directional selection, which are expected to have reduced levels of variation. Following a population bottleneck, the signal of directional selection may be hard to detect because many loci may have low variation by chance and the frequency spectrum of variation may be perturbed in ways that resemble the effects of selection. Cultivated Sorghum bicolor contains a subset of the genetic diversity found in its wild ancestor(s) due to the combined effects of a domestication bottleneck and human selection on traits associated with agriculture. As a framework for distinguishing between the effects of demography and selection, we sequenced 204 loci in a diverse panel of 17 cultivated S. bicolor accessions. Genomewide patterns of diversity depart strongly from equilibrium expectations with regard to the variance of the number of segregating sites, the site frequency spectrum, and haplotype configuration. Furthermore, gene genealogies of most loci with an excess of low frequency variants and/or an excess of segregating sites do not show the characteristic signatures of directional and diversifying selection, respectively. A simple bottleneck model provides an improved but inadequate fit to the data, suggesting the action of other population-level factors, such as population structure and migration. Despite a known history of recent selection, we find little evidence for directional selection, likely due to low statistical power and lack of an appropriate null model.

Agriculture↗
PubMed2006

Discriminative analysis of relapsing neuromyelitis optica and relapsing-remitting multiple sclerosis based on two-dimensional histogram from diffusion tensor imaging.

It is difficult to completely differentiate patients with relapsing neuromyelitis optica (RNMO) from relapsing-remitting multiple sclerosis (RRMS) for their similarities in clinical manifestation. In this study, we proposed a novel approach, using two-dimensional histogram of apparent diffusion coefficient (ADC) and fractional anisotropy (FA) of the brain derived from diffusion tensor imaging (DTI) as classification feature, to discriminate patients with RNMO from RRMS. In this approach, two-dimensional principal component analysis (2D-PCA) was used to extract feature and reduce dimensionality of matrix-formed data efficiently. Then linear discriminant analysis (LDA) was performed on these extracted features to find the best projection direction to separate patients with RNMO from RRMS. Finally, a minimum distance classifier was generated on the basis of projection scores. The correct recognition rate of our method reached 85.7%, validated by the leave-one-out method. This result was much higher than that using feature of ADC or FA separately (59.5% for ADC, 76.2% for FA). In conclusion, the proposed method on the basis of combined features is more effective for classification than those merely using the features separately, and it may be helpful in differentiating RNMO from RRMS patients.

Diffusion Magnetic Resonance Imaging↗
PubMed2006

Involvement of CUL4 ubiquitin E3 ligases in regulating CDK inhibitors Dacapo/p27Kip1 and cyclin E degradation.

The CUL4 (cullin 4) proteins are the core components of a new class of ubiquitin E3 ligases that regulate replication and transcription. To examine the roles of CUL4 in cell cycle regulation, we analyzed the effect of inactivation of CUL4 in both Drosophila and human cells. We found that loss of CUL4 in Drosophila cells causes G(1) cell cycle arrest and an increased protein level of the CDK inhibitor Dacapo. Coelimination of Dacapo with CUL4 abolishes the G(1) cell cycle arrest. In human cells, inactivation of CUL4A induces CDK inhibitor p27(Kip1) stabilization and G(1) cell cycle arrest which is dependent on the presence of p27, suggesting that this regulatory pathway is evolutionarily conserved. In addition, we found that the Drosophila CUL4 also regulates the protein level of cyclin E independent of Dacapo. We provide evidence that human CUL4B, a paralogue of human CUL4A, is involved in cyclin E regulation. Loss of CUL4B causes the accumulation of cyclin E without a concomitant increase of p27. The human CUL4B and cyclin E proteins also interact with each other and the CUL4B complexes can polyubiquitinate the CUL4B-associated cyclin E. Our studies suggest that the CUL4-containing ubiquitin E3 ligases play a critical role in regulating G(1) cell cycle progression in both Drosophila and human cells.

Animals↗
PubMed2006

Alcohol-induced impairment of neuronal nitric oxide synthase (nNOS)-dependent dilation of cerebral arterioles: role of NAD(P)H oxidase.

The goal of the present study was to determine the role of NAD(P)H oxidase in alcohol consumption-induced impairment of nNOS-dependent reactivity in cerebral arterioles. Sprague-Dawley rats were fed an alcohol diet for 2-3 months. We measured the effects of acute (1 hour) and chronic (1 month) treatment with a NAD(P)H oxidase inhibitor, apocynin, on responses of parietal pial arterioles to nNOS-dependent agonists (NMDA and kainate) and an nitric oxide synthase (NOS)-independent agonist (nitroglycerin). In addition, we measured the expression of NAD(P)H oxidase subunits and superoxide production in parietal cortex. Topical application of NMDA and kainate produced dose-related dilation of pial arterioles. However, the magnitude of vasodilation to these agonists was significantly less in alcohol-fed rats. Treatment with apocynin (acute and chronic) did not alter vasodilation in nonalcohol-fed rats, but significantly improved vasodilation in alcohol-fed rats. Response of pial arterioles to nitroglycerin was similar in nonalcohol-fed and alcohol-fed rats, and was not affected by apocynin. In addition, we found an up-regulation of gp91phox and p47phox in parietal cortex of alcohol-fed rats. Finally, alcohol consumption produced an increase in superoxide production under basal conditions and in the presence of NADPH. Acute treatment with apocynin suppressed alcohol consumption-induced superoxide generation. Our findings suggest that NAD(P)H oxidase plays an important role in chronic alcohol consumption-induced impairment of nNOS-dependent dilation of cerebral arterioles.

Acetophenones↗
PubMed2006

p120 nucleolar-proliferating antigen is a direct target of G-CSF signaling during myeloid differentiation.

Granulocyte-colony stimulating factor (G-CSF) is an essential cytokine, which contributes to proliferation and differentiation of granulocyte precursor cells in the bone marrow. Despite recent progress in understanding G-CSF signaling events, the mechanisms that underlie the distinct spectrum of biological functions attributed to G-CSF-mediated gene expression remain unclear. Previous studies have identified a number of genes, which are up-regulated in G-CSF-stimulated myeloid precursor cells. In this study, we sought to identify additional target genes of G-CSF-mediated proliferation and/or differentiation. cDNA representational difference analysis was used with the 32Dcl3 cell line as a model system to isolate genes, which are up-regulated in an immediate-early manner upon G-CSF stimualtion. We isolated p120 nucleolar-proliferation antigen (NOL1), a highly conserved, nucleolar-specific, RNA-binding protein of unknown function, and confirmed its expression by Northern blot analysis in 4-h, G-CSF-induced 32Dcl3 cells. Isolation of a mouse p120 genomic clone revealed the presence of a signal tranducer and activator of transcription (STAT)-binding site in the first intron of the gene. We demonstrate the importance of STAT3 and STAT5 in mediating the G-CSF response with respect to p120 expression by transient transfection analysis, oligonucleotide pull-down assays, and the loss of p120 expression in the bone marrow of mice lacking normal STAT3 signaling. In addition, overexpression of p120 in G-CSF-induced 32D cells revealed normal, morphologic maturation and growth characteristics but loss of lactoferrin expression, a marker of normal neutrophil maturation, suggesting that inappropriate expression of the p120 gene can result in aberrant neutrophil maturation.

Animals↗
PubMed2006

[Causes and revision endoscopic sinus surgery for recurrent sinusitis].

OBJECTIVE: To investigate the causes of revision endoscopic sinus surgery (RESS), and to evaluate the clinical effect and experience of RESS in the patients with recurrent sinusitis. METHODS: Before the revision surgery, 168 patients (225 sides) with recurrent sinusitis were examed by CT scans and nasal endoscopy. All patients were operated by revision endoscopic sinus surgery. RESULTS: Among the 168 patients, 95 cases (121 sides) had incomplete middle turbinate, 51 cases (75 sides) had maxillary sinus ostium stenosis, 85 cases (117 sides) had nasal cavity adhesion, 48 cases (57 sides) had uncinate process residual, 38 cases (65 sides) had ethmoid hyperostosis, and 25 cases had nasal septum deviation. One hundred and six patients (134 sides) were cured, 40 patients (56 sides) were improved, useful 22 patients (35 sides) were ineffective. CONCLUSION: The most common surgical causes of failures in endoscopic sinus surgery are the disease area remnant, nasal cavity adhesion, maxillary sinus ostium stenosis, uncinate process residual, ethmoid hyperostosis, and nasal septum deviation. Revision endoscopic sinus surgery is a useful way to treat recurrent sinusitis. Preoperative CT scan, correct choice of the anatomic marks of orientation and direction function are the key to operation successful.

Adolescent↗
PubMed2006

[The effect of surface free energy parameters of diamond-like carbon films deposited on medical polyethylene terephthalate on bacterial adhesion].

Diamond-like carbon (DLC) films were deposited by acetylene plasma immersion ion implantation-deposition (PIII-D) on biomedical polyethylene terephthalate (PET). The capacities of Staphylococcus aureus (SA), Staphylococcus epidermidis (SE), Escherichia coli (EC), Pseudomonas aeruginosa (PA) and Candida albicans (CA) for adhesion to PETs are quantitatively determined by the plate counting and Gamma-ray counting of 125I radio labeled bacteria in vitro. The results indicate that the capacities of five types of bacteria for adhesion to PETs are all suppressed by C2H2 PIII-D (P<0.05). The surface energy components of the various substrates and bacteria are calculated based on measurements in water, formamide and diiodomethane and Lifshitz-van del Waals/acid-base approach (LW-AB). The surface free energies obtained are used to calculate the interfacial free energies of adhesion (deltaF(adh)) of five kinds of bacteria on various substrates, and the results show that it is energetically unfavorable for bacterial adhesion to the DLC films already deposited on PET by C2H2 PIII-D.

Bacterial Adhesion↗
PubMed2006

[Differential proteins analysis for human nasal polyposis and normal nasal mucosa].

OBJECTIVE: To establish two-dimensional polyacrylamide gel electrophoresis (2-DE) map with high resolution and reproducibility from human nasal polyposis and normal nasal mucosa, and to identify differential expression proteins of 2-DE map. METHOD: Samples of human nasal polyposis and normal nasal mucosa (each sample group containing seven cases) were obtained. The total proteins were extracted and separated by immobilized pH gradient (IPG)-based 2-DE. The silver-stained 2-DE were scanned with digital Image Scanner and analyzed with ImageMaster 2-DE Elite 4.01 software. Peptide mass fingerprint (PMF) of differential protein spots was obtained with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The peptide mass fingerprints were searched in Swiss-Prot and TreMBL database by PeptIdent software, and then differential expression proteins were identified. RESULT: (1) 2-DE for a randomly selected 1 sample from each of the 2 groups was repeated 3 times respectively to analyze the reproductive of the method. The image analysis showed: For the polyposis tissues, the average proteins spots of three 2-DE maps were 891 +/- 67 and 767 +/- 83, spots were matched with the average matching rate of 86.1%. The average deviations of matched spot position were (1.13 +/- 0.16) mm in IEF direction and 1.45 +/- 0.21) mm in SDS-PAGE direction, respectively. For the nasal mucosa tissues, the average proteins spots of three 2-DE maps were 936 +/- 62 and 821 +/- 78, spots were matched with the average matching rate of 87.7%. Comparing the average electrophoresis profiles of the two tissues, each sample contained 7 cases. The proteins spots of nasal polyposis and nasal mucosa tissues were 1532 and 1617. A total of 1 065 proteins spots were matched between the two tissues average electrophoresis profiles. (2)Twenty dif-ferential expression protein spots were incised from silver staining gel randomly and digested in gel by TPCK Trypsin. Sixteen PMF were obtained by MALDI-TOF-MS, and 11 differential expression proteins were identified. CONCLUSION: In this study, the well-resolved reproducible 2-DE map of human nasal polyposis and nasal mucosa were established. Certain differential proteins were identified.

Adult↗
PubMed2006

[Determination of differentially expressed proteins and it's significance among chronic sinusitis, nasal polyps and normal nasal mucosa].

OBJECTIVE: To investigate the differentially expressed proteins among chronic sinusitis, nasal polyps and normal nasal mucosa by means of proteomic technology, and select the candidate biomarkers of chronic sinusitis and nasal polyps. METHODS: Proteins extracted from chronic sinusitis, nasal polyps and normal nasal mucosa were separated and the differentially expressed proteins were identified by series of proteomic tools, including immobilized pH4-7 gradient two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis, modified coomassie brilliant blue staining, images scanning by the Image Scanner apparatus, PDQuest analysis software, peptide mass fingerprinting based on matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS) by in-gel digestion extract, and Mascot searching in NCBInr and SWISS-PROT databases. RESULTS: The 2-DE patterns with high resolution and reproducibility were obtained. The protein spots separated and visualized in chronic sinusitis, nasal polyps and normal nasal mucosa gel were 1020 +/- 40, 1112 +/- 10 and 1008 +/- 25, respectively. And the match rates were (93 +/- 2)%, (95 +/- 1)% [see text] (90 +/- 3)% respectively. Thirteen differentially expressed spots were found from chronic sinusitis, nasal polyps and normal nasal mucosa gel. We selected and recommend Keratin 8 and APOA1 proteins as candidate biomarkers of nasal polyps, and PLUNC protein, PACAP protein, NKEF-B and SOD as candidate biomarkers of chronic sinusitis. CONCLUSIONS: The differentially expressed proteins among chronic sinusitis, nasal polyps and normal nasal mucosa can be efficiently and relatively reliably identified via the techniques of proteomics. These techniques will play a very important role in the researches for new objective indicators possibly employed in the future classifying, staging and prognosis.

Adolescent↗
PubMed2006

[Clinical observation on the method for nourishing blood and moisturizing eye on xerophthalmia].

OBJECTIVE: To observe therapeutic effect of the method for nourishing blood and moisturizing eye on xerophthalmia. METHODS: Fifty-one cases of xerophthalmia were randomly divided into a treatment group and a control group. The treatment group were treated by acupuncture, moxibustion with Chinese medicine, and auricular point pressing, and the control group were treated with dripping of artificial tears. Local symptoms of eyes, tear secretion amount (Schirmer method) and BUT were observed before and after treatment. RESULTS: The total effective rate of 88.5% in the treatment group was better than 52.0% in the control group (P<0.05). CONCLUSION: The method for nourishing blood and moisturizing eye is a better therapy for xerophthalmia.

Acupuncture↗
PubMed2006

[Establishment of 2-dimensional gel electrophoresis map and analysis of proteomics from human nasal polyps].

OBJECTIVE: To establish 2-dimensional polyacrylamide gel electrophoresis (2-DE) map from human nasal polyps and normal nasal mucosa, and to identify differential expression proteins of 2-DE map. METHODS: Samples of nasal polyps and nasal mucosa (each sample group containing 7 cases) were obtained. The total proteins were extracted and separated by immobilized pH gradient (IPG)-based 2-DE. The silver-stained 2-DE was scanned with digital Imagescanner and analyzed with ImageMaster 2-DE Elite 4.01 software. To obtain peptide mass fingerprint (PMF) of differential protein spots, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was used. The PMF was searched in Swiss-Prot and TreMBL database by Pept-Ident software, to identify differential expression proteins. RESULTS: The well-resolved, reproducible 2-DE maps of nasal polyps and nasal mucosa were established. For the polyps tissues, the average proteins spot of three 2-DE maps was 825+/-78; and 682+/-96 spot was matched with the average matching rate of 82.7%. The average deviations of matched spot position were (1.13+/-0.16) mm in IEF direction and (1.45+/-0.21) mm in SDS-PAGE direction, respectively. For the nasal mucosa tissues, the average proteins spot of three 2-DE maps was 936+/-62; and 821+/-78 spots were matched with the average matching rate of 87.7%. After comparing the 2-DE maps of nasal polyps and nasal mucosa tissues, the protein spots were 1,458 and 1,617 respectively; and 1,026 protein spots were matched. Forty differential expression protein spots were incised from silver staining gel randomly and digested in the gel by TPCK-Trypsin. Thirty-four PMFs were obtained by MALDI-TOF-MS and 24 differential proteins were identified. CONCLUSION: The well-resolved, reproducible 2-DE maps of human nasal polyps and nasal mucosa have been successfully established. Certain differential proteins related to the pathogenesis of human nasal polyps are identified.

Adult↗
PubMed2006

[Effect of TCM formula for promoting blood circulation to remove blood stasis on brainstem auditory evoked potential and Transcranial Doppler parameters in patients with sudden deafness].

OBJECTIVE: To observe the therapeutic effect of Xuefu Zhuyu Decoction (XZD) on patients with sudden deafness (SD). METHODS: Sixty patients with SD were treated with XZD, and the changes of brainstem auditory evoked potential (BAEP) and transcranial Doppler (TCD) parameters in them were detected before and after treatment and analyzed statistically. RESULTS: I, III and V waveform and peak latency (PL) of BAEP, velocity of vertebral basilar arterial blood flow and parameters of cerebral blood flow in SD patients were all improved to different levels after treatment with XZD. CONCLUSION: TCM formula for promoting blood circulation to remove blood stasis can improve BAEP and TCD parameters in SD patients; BAEP detection and TCD parameters can reflect nerve function and blood-supply state of internal ear and brain stem, and therefore are of great importance in guiding the clinical treatment and assessing the prognosis.

Adult↗
PubMed2006

Preparation and characterization of HLA-A*0201 tetramer loaded with IE-1316-324 antigenic peptide of human cytomegalovirus.

Major histocompatibility complex (MHC) class I tetramer technology has become the central technique for analyzing antigen-specific CD8(+) T cell responses and it has been widely used to explore the differentiation and formation of memory CD8(+) T cells. Previously, a simplified and efficient procedure for preparing high quality HLA-A*0201 tetramers has been established in our lab and the tetramers loaded with HCMV peptide pp65(495-503) has been successfully applied to investigate HCMV-specific CD8(+) T cells in Chinese populations. Using similar procedure we reported here the construction of HLA-A*0201 tetramer loaded with another dominant epitope derived from immediate early (IE)-1(316-324) (VLEETSVML, VLE) of HCMV (A2-VLE) and characterization of this tetramer. After A2-VLE monomer was prepared and purified, its tetramer was then formed at a yield of 83%. The optimized amount of A2-VLE tetramer for staining 100 microl whole blood was 0.5 microg with incubation at 4 degrees C for 1 h. Furthermore, the dissociation constant of the tetramer binding to the specific CD8(+) T cells of one HLA-A2(+) donor was estimated to be 32.7 nmol/L, which is markedly higher than that of MHC monomer. The construction of A2-VLE tetramer provides an alternative choice for investigating HCMV-specific CD8(+) T cell responses and will deepen our understanding of the differentiation and formation of HCMV-specific memory CD8(+) T cells.

Biotin↗
PubMed2006

[Analysis on the anatomic features of 47 cases of hepatic hydatidosis complicated with biliary fistula].

OBJECTIVE: To propose a criterion and its significance of clinical classification of hepatic hydatidosis complicated with biliary fistula. METHODS: 47 hepatic hydatidosis with biliary fistula cases who were given a subadventitial pericystectomy were observed from 2000 to 2005 in a retrospective study. The methods included observation of the different anatomic features of hepatic hydatidosis complicated with biliary fistula during the surgical operation and evaluation of the curative effect. RESULTS: All the 47 patients recuperated successfully and had no complication. Based on the anatomic features of hepatic hydatidosis complicated with biliary fistula, a criterion on clinical classification was proposed as three types: tangential, transfixional and terminal types. CONCLUSIONS: Hepatic hydatidosis complicated with biliary fistula can be classified as three types according to its anatomic features.

Adult↗
PubMed2006

[Expression of osteopontin in the pericystic layer of hepatic hydatid cyst].

OBJECTIVE: To investigate the expression and distribution of osteopontin (OPN) in the pericystic layer of Echinococcus granulosus cyst. METHODS: 60 surgically excised cysts were studied with HE and immunohistochemistry staining by using antibodies specific for OPN. Immunofluorescence double labeling technique and Media Cybernetics Image (Pro Plus 5.1 software) were used to appraise the relationship between the OPN and macrophages (CD68). RESULTS: Expression of OPN was found at various degree in hydatid cysts, 75% (45/60) was distributed in the intra-layer at the parasite side, 8.3% (5/60) distributed in the extra-layer near the side of liver parenchyma ("exocyst"-layer vs "adventitia"-layer, P<0.01). Macrophages were identified between the intra-layer and extra-layer, and OPN was observed in most of the macrophages. Meanwhile, OPN was concurrently found with the deposit of calcium in a similar distribution in the hydatid cyst. CONCLUSION: Osteopontin mainly distributes in the intra-pericystic layer of hepatic hydatid cyst.

Adolescent↗