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Xiaohong Wang

Publications and source records attributed to Xiaohong Wang.

At least 19 recordsLinked to original sources
PubMed2026

[Optical genome mapping analysis of a Chinese pedigree with a complex balanced translocation involving four chromosomes].

OBJECTIVE: To explore the genetic characteristics of a complex balanced translocation involving four non-homologous chromosomes in a Chinese pedigree using optical genomic mapping (OGM). METHODS: A woman with primary infertility and her family members who presented at the Prenatal Diagnosis Center of the Sixth Affiliated Hospital of Sun Yat-sen University in October 2021 were selected as study subjects. Comprehensive analysis and verification of chromosomal abnormalities were conducted through conventional G-band karyotyping analysis, single nucleotide polymorphism microarray (SNP array) and OGM. This study was approved by the Medical Ethics Committee of the hospital (Ethics No.: E2022210). RESULTS: G-band karyotyping analysis indicated that the proband, her father, and younger brother have all carried a complex translocation involving four chromosomes. SNP array analysis revealed a duplication of approximately 21.63 Mb in the 9p24.1-p21.1 region in the proband's younger brother, while no abnormality was detected in other family members. OGM confirmed that the complex balanced translocation has involved chromosomes 5, 8, 9, and 10. CONCLUSION: The proband has harbored a complex balanced translocation. OGM has demonstrated certain advantages in characterization of complex chromosomal structural abnormalities.

Humans↗
PubMed2007

Enzymatic production of biosilica glass using enzymes from sponges: basic aspects and application in nanobiotechnology (material sciences and medicine).

Biomineralization, biosilicification in particular (i.e. the formation of biogenic silica, SiO2), has become an exciting source of inspiration for the development of novel bionic approaches following "nature as model". Siliceous sponges are unique among silica forming organisms in their ability to catalyze silica formation using a specific enzyme termed silicatein. In this study, we review the present state of knowledge on silicatein-mediated "biosilica" formation in marine sponges, the involvement of further molecules in silica metabolism and their potential application in nanobiotechnology and medicine.

Amino Acid Sequence↗
PubMed2006

Xenotransplantation of long-term-cultured swine bone marrow-derived mesenchymal stem cells.

Swine-derived MSCs were efficiently isolated and extensively expanded using a low fetal serum content growth medium to which selected growth factors were added. After > or =96 cell population doublings (PDs), MSCs were devoid of cytogenetic abnormalities. In vitro chondrogenic and osteogenic differentiation capacity was preserved after 80 PDs. To test therapeutic efficacy, 1 x 10(6) 80-PD MSCs were injected directly into the peri-infarct zone of hearts of immunodeficient (non-obese diabetic/severe combined immunodeficient) mice at the time of acute myocardial infarction. Engrafted MSCs survived in the infarcted hearts for at least 4 weeks. Echocardiography at 2 and 4 weeks postinfarction revealed a significant preservation of the left ventricular ejection fractions of infarct hearts receiving MSCs compared with infarct hearts receiving saline. Peri-infarct zone capillarity was better preserved in MSC-treated hearts than other infarct groups of hearts, but infarct size was comparable in all groups. Only rare engrafted MSCs expressed cardiac-specific or endothelial cell-specific markers. Hence, 80-PD MSCs retained the capacity to promote functional improvement in the infarcted heart despite minimal differentiation of MSCs into cardiomyocytes or endothelial cells. These data suggest that the beneficial effects of MSC transplantation most likely result from the trophic effects of MSC-released substances on native cardiac and vascular cells. The capacity to massively expand MSC lines without loss of therapeutic efficacy may prove to be useful in the clinical setting where "off the shelf" MSCs may be required for interventions in patients with acute coronary syndromes.

Adenoviridae↗
PubMed2006

Legume genome evolution viewed through the Medicago truncatula and Lotus japonicus genomes.

Genome sequencing of the model legumes, Medicago truncatula and Lotus japonicus, provides an opportunity for large-scale sequence-based comparison of two genomes in the same plant family. Here we report synteny comparisons between these species, including details about chromosome relationships, large-scale synteny blocks, microsynteny within blocks, and genome regions lacking clear correspondence. The Lotus and Medicago genomes share a minimum of 10 large-scale synteny blocks, each with substantial collinearity and frequently extending the length of whole chromosome arms. The proportion of genes syntenic and collinear within each synteny block is relatively homogeneous. Medicago-Lotus comparisons also indicate similar and largely homogeneous gene densities, although gene-containing regions in Mt occupy 20-30% more space than Lj counterparts, primarily because of larger numbers of Mt retrotransposons. Because the interpretation of genome comparisons is complicated by large-scale genome duplications, we describe synteny, synonymous substitutions and phylogenetic analyses to identify and date a probable whole-genome duplication event. There is no direct evidence for any recent large-scale genome duplication in either Medicago or Lotus but instead a duplication predating speciation. Phylogenetic comparisons place this duplication within the Rosid I clade, clearly after the split between legumes and Salicaceae (poplar).

Chromosomes, Plant↗
PubMed2006

High level expression of human epithelial beta-defensins (hBD-1, 2 and 3) in papillomavirus induced lesions.

BACKGROUND: Epithelial defensins including human beta-defensins (hBDs) and alpha-defensins (HDs) are antimicrobial peptides that play important roles in the mucosal defense system. However, the role of defensins in papillomavirus induced epithelial lesions is unknown. RESULTS: Papilloma tissues were prospectively collected from 15 patients with recurrent respiratory papillomatosis (RRP) and analyzed for defensins and chemokine IL-8 expression by quantitative, reverse-transcriptase polymerase chain reaction (RT-PCR) assays. HBD-1, -2 and -3 mRNAs were detectable in papilloma samples from all RRP patients and the levels were higher than in normal oral mucosal tissues from healthy individuals. Immunohistochemical analysis showed that both hBD-1 and 2 were localized in the upper epithelial layers of papilloma tissues. Expression of hBD-2 and hBD-3 appeared to be correlated as indicated by scatter plot analysis (r = 0.837, p < 0.01) suggesting that they were co-inducible in papillomavirus induced lesions. Unlike hBDs, only low levels of HD5 and HD6 were detectable in papillomas and in oral mucosa. CONCLUSION: Human beta-defensins are upregulated in respiratory papillomas. This novel finding suggests that hBDs might contribute to innate and adaptive immune responses targeted against papillomavirus-induced epithelial lesions.

Adult↗
PubMed2006

Indian hedgehog, but not histidine decarboxylase or amphiregulin, is a progesterone-regulated uterine gene in hamsters.

Implantation occurs only in the progesterone (P4)-primed uterus in the majority of species, but little effort has been given to identify P4-mediated molecules in these species. Using hamsters as a model for P4-dependent implantation and three well-known uterine receptivity-associated P4-regulated genes, Indian hedgehog (Ihh), histidine decarboxylase (Hdc), and amphiregulin (Areg), in mice that require ovarian estrogen for uterine receptivity and implantation, our strategy aimed to determine whether P4 regulates uterine expression of these genes in hamsters and whether the event- and cell-specific uterine expression patterns of these genes during the periimplantation period in hamsters follow similarly with their patterns in mice. We report here that P4-mediated Ihh signaling is important for uterine receptivity and implantation in hamsters because uterine epithelial Ihh expression was regulated by P4 and its expression patterns during the periimplantation period of hamsters closely follow its pattern in mice. In contrast, we noted no hormonal regulation of Hdc and Areg in the hamster uterus. However, this did not diminish their importance in hamsters because their expression patterns and functions are event and cell specific during the periimplantation period: whereas Hdc was expressed exclusively in d 4 uterine glands and regulated by the blastocyst, Areg was expressed on the decidual area adjacent to the embryo from d 5 onward and involved in stromal cell proliferation. We conclude that similarities and dissimilarities exist in uterine expression pattern of implantation-related genes, including hormonal regulation and their event-specific importance.

Amphiregulin↗
PubMed2006

Efficacy of risperidone versus olanzapine in patients with schizophrenia previously on chronic conventional antipsychotic therapy: a switch study.

The objective of the study was to examine whether patients with schizophrenia who were judged to be stable on long-term treatment with conventional antipsychotic medications would further benefit from a switch to an atypical antipsychotic drug. Thirty-six subjects with schizophrenia spectrum disorder, on conventional antipsychotic medication therapy for at least 2 years, were randomized in double-blind fashion to risperidone versus olanzapine. Patients were titrated up to 6 mg risperidone or 15 mg olanzapine as tolerated, followed by tapering and discontinuation of conventional antipsychotic medication. Atypical antipsychotic agents were then administered alone (monotherapy) for 12 weeks. Efficacy and tolerability were assessed using the Positive and Negative Syndrome Scale (PANSS), Clinical Global Impression Scale, and Simpson Angus Scale. Body weight was measured at each visit. Both treatment groups exhibited marked and similar improvement in the total PANSS score from baseline to study endpoint (22 weeks) [risperidone: baseline=59.3 (SE 3.1), 22 weeks=44.3 (SE 2.3) (p<0.001); olanzapine: baseline=55.9 (SE 3.3), 22 weeks=46.9 (SE 3.2) (p<0.001). Both groups also exhibited significant reductions in PANSS factor scores for positive and negative symptoms and disorganized thoughts. Only risperidone-treated patients exhibited significant decreases in uncontrolled hostility/excitement and anxiety and depression. Of note, while positive factor scores exhibited the majority of change within the first 10 weeks, negative factor scores continued to decline significantly in both treatment groups throughout the study. Tolerability assessments did not differ between groups. The results indicate that both atypical antipsychotic medications provided significant additional improvement in symptom severity in patients with schizophrenia previously on conventional antipsychotic agents.

Adult↗
PubMed2006

Polymer-functionalized multiwalled carbon nanotubes as lithium intercalation hosts.

Multiwalled carbon nanotubes (MWNTs) functionalized with a hyperbranched aliphatic polyester and two different poly(ethylene glycol)s were synthesized by the reactions of carbonyl chloride groups on the surface of MWNTs and hydroxyl groups of polymers. Electrochemical intercalation of lithium in the three materials was investigated with galvanostatic charge-discharge experiments. The hyperbranched polymer-functionalized MWNT as an electrode material for lithium batteries showed a significant improvement over linear polymer-functionalized MWNTs in lithium insertion/deinsertion capacity and cycle stability. The MWNT functionalized with linear poly(ethylene glycol) showed a high initial capacity of lithium insertion/deinsertion but had the highest capacity fade rate among the materials. Because the polymers were chemically localized in the electrode-electrolyte interface, the comparison between hyperbranched and linear polymer-modified MWNTs manifested the important influence of the electrode-electrolyte interface on the electrochemical properties of lithium batteries.

Journal Article↗
PubMed2006

The role of the sca-1+/CD31- cardiac progenitor cell population in postinfarction left ventricular remodeling.

Cardiac stem cell-like populations exist in adult hearts, and their roles in cardiac repair remain to be defined. Sca-1 is an important surface marker for cardiac and other somatic stem cells. We hypothesized that heart-derived Sca-1(+)/CD31(-) cells may play a role in myocardial infarction-induced cardiac repair/remodeling. Mouse heart-derived Sca-1(+)/CD31(-) cells cultured in vitro could be induced to express both endothelial cell and cardiomyocyte markers. Immunofluorescence staining and fluorescence-activated cell sorting analysis indicated that endogenous Sca-1(+)/CD31(-) cells were significantly increased in the mouse heart 7 days after myocardial infarction (MI). Western blotting confirmed elevated Sca-1 protein expression in myocardium 7 days after MI. Transplantation of Sca-1(+)/CD31(-) cells into the acutely infarcted mouse heart attenuated the functional decline and adverse structural remodeling initiated by MI as evidenced by an increased left ventricular (LV) ejection fraction, a decreased LV end-diastolic dimension, a decreased LV end-systolic dimension, a significant increase of myocardial neovascularization, and modest cardiomyocyte regeneration. Attenuation of LV remodeling was accompanied by remarkably improved myocardial bioenergetic characteristics. The beneficial effects of cell transplantation appear to primarily depend on paracrine effects of the transplanted cells on new vessel formation and native cardiomyocyte function. Sca-1(+)/CD31(-) cells may hold therapeutic possibilities with regard to the treatment of ischemic heart disease.

Animals↗
PubMed2006

Profound bioenergetic abnormalities in peri-infarct myocardial regions.

Regions of myocardial infarct (MI) are surrounded by a border zone (BZ) of normally perfused but dysfunctional myocardium. Although systolic dysfunction has been attributed to elevated wall stress in this region, there is evidence that intrinsic abnormalities of contractile performance exist in BZ myocardium. This study examined whether decreases of high-energy phosphates (HEP) and mitochondrial F(1)F(0)-ATPase (mtATPase) subunits typical of failing myocardium exist in BZ myocardium of compensated postinfarct remodeled hearts. Eight pigs were studied 6 wk after MI was produced by ligation of the left anterior descending coronary artery (LAD) distal to the second diagonal. Animals developed compensated LV remodeling with a decrease of ejection fraction from 54.6 +/- 5.4% to 31 +/- 2.1% (MRI) 5 wk after LAD occlusion. The remote zone (RZ) myocardium demonstrated modest decreases of ATP and mtATPase components. In contrast, BZ myocardium demonstrated profound abnormalities with ATP levels decreased to 42% of normal, and phosphocreatine-to-ATP ratio ((31)P-magnetic resonance spectroscopy) decreased from 2.06 +/- 0.19 in normal hearts to 1.07 +/- 0.10, with decreases in alpha-, beta-, OSCP, and IF(1) subunits of mtATPase, especially in the subendocardium. The reduction of myocardial creatine kinase isoform protein expression was also more severe in the BZ relative to the RZ myocardium. These abnormalities were independent of a change in mitochondrial content because the mitochondrial citrate synthase protein level was not different between the BZ and RZ. This regional heterogeneity of ATP content and expression of key enzymes in ATP production suggests that energetic insufficiency in the peri-infarct region may contribute to the transition from compensated LV remodeling to congestive heart failure.

Adenosine Diphosphate↗
PubMed2006

A role for muscle LIM protein (MLP) in vascular remodeling.

Given the well-defined role of LIM-motif containing proteins in cytoskeletal organization, cell fate, and differentiation, we hypothesized that the regulation of LIM proteins played an integral role in vascular remodeling. We screened a compendium of cDNA microarray data from rat vascular smooth muscle cells (VSMC) for novel LIM-containing targets and identified muscle LIM protein (MLP), a gene previously thought to be only in striated muscle. Sequence analysis, RTQPCR and Western blotting reconfirmed expression of MLP in VSMC. MLP was elevated>10-fold 7 days following balloon injury in the rat carotid artery. Wire injury led to a significantly increased intima/media ratio in MLP -/- mice compared to wild-type controls (P<0.007, N=5). Fas-ligand and ceramide-induced apoptosis were significantly decreased in MLP deficient VSMC (n=6, P<0.001). Adenoviral-induced restoration of MLP significantly restored apoptotic response (N=6, P<0.001). These findings are the first to identify MLP in vascular smooth muscle and demonstrate that it plays a critical role in vascular remodeling. This is consistent with earlier findings demonstrating a role for MLP in striated muscle remodeling in response to load and stretch.

Animals↗
PubMed2006

Growth mechanism of penniform BaWO4 nanostructures in catanionic reverse micelles involving polymers.

The formation of penniform BaWO4 nanostructures made of nanowires or nanobelts under the direction of a block copolymer in catanionic reverse micelles has been studied in detail. On the basis of the experimental results obtained from the BaWO4 crystallization in aqueous polymer solutions and careful transmission electron microscopy (TEM) observations of BaWO4 nanostructures formed in reverse micelles containing polymers, a detailed two-stage growth mechanism has been proposed for the formation of the penniform nanostructures in reverse micelles, which involves the polymer-controlled shaft formation (Stage 1) and the mixed surfactants-controlled barb growth (Stage 2). During Stage 1, poly(ethylene glycol)-block-poly(methacrylic acid) (PEG-b-PMAA) induced the formation of c-axis-oriented shuttle-like nanocrystals and the subsequent oriented attachment of these shuttle-like nanocrystals resulted in the formation of [100]-oriented shafts with many parallel [001]-oriented pricks. During Stage 2, [001]-oriented nanowires or nanobelts grew gradually from the pricks into barbs, leading to the formation of well-defined penniform BaWO4 nanostructures with the barb morphology essentially determined by the mixing ratio r of the anionic to cationic surfactants (i.e., nanowires were formed at r=1 while nanobelts were formed at r deviating from 1). The current understanding of the growth mechanism of penniform BaWO4 nanostructures in catanionic reverse micelles involving polymers may be potentially applied for designing a new synthesis system for the controlled synthesis of other hierarchical 1D nanostructures with desired architectures.

Journal Article↗
PubMed2006

Open-chest 31P magnetic resonance spectroscopy of mouse heart at 4.7 Tesla.

PURPOSE: To develop a rapid, robust, and accurate method for assessing myocardial energetics in mice and demonstrate its applicability to mouse models of acquired and genetic heart disease. MATERIALS AND METHODS: We combined surface coil localization (10-mm diameter, tunable between (1)H and (31)P, using adiabatic half-passage radiofrequency pulses) and surgery (electrocautery removal of anterior chest wall) to create an open-chest method for acquiring in vivo (31)P nuclear magnetic resonance (NMR) cardiac spectra from mice at 4.7T within 12 minutes. Normal BALB/c mice, BALB/c with myocardial infarction (MI), cardiomyocyte-restricted peroxisome proliferator-activated receptor-delta knockout (KO) (CR-PPARd(-/-)) and control loxP-flanked Ppard (Ppard(flox/flox)) mice were examined. RESULTS: The mean phosphocreatine (PCr)/adenosine triphosphate (ATP) ratios in control BALB/c mice, BALB/c MI mice, Ppard(flox/flox) mice, and PPAR-delta KO mice were 2.13 +/- 0.09 (N = 11), 1.35 +/- 0.07 (N = 9, P < 0.001 vs. BALB/c control), 1.92 +/- 0.09 (N = 5), and 1.31 +/- 0.12 (N = 5, P < 0.005 vs. Ppard(flox/flox) control), respectively. The significant depression of myocardial PCr/ATP we observed in these genetic/acquired models of heart disease was in accord with previous data from analogous large animal models. No NMR signal contamination from chamber blood or adjacent skeletal muscle was identified. CONCLUSION: This new technique provides cardiac (31)P spectra suitable for accurate quantitative analysis in a relatively short acquisition time, is suitable for terminal studies of mouse myocardial energy metabolism, and could be installed in virtually any NMR laboratory to study myocardial energetics in numerous mouse models of human heart disease.

Adenosine Triphosphate↗
PubMed2006

The effectiveness of Nd:YAG laser capsulotomy for the treatment of posterior capsule opacification in children with acrylic intraocular lenses.

INTRODUCTION: Acrylic intraolcular lenses (IOLs) may result in lower rates of posterior capsular opacification (PCO) than poly(methyl methacrylate) lenses in children. Nonetheless, PCO frequently occurs eventually, especially in younger children. Here, we evaluated the success of neodymium-doped yttrium-aluminum-garnet (Nd:YAG) laser capsulotomy for the management of PCO after acrylic IOL implantation without primary capsulectomy. METHODS: We reviewed 73 eyes in 57 children (age 23 months to 12 years; median, 6.4 years) who underwent Nd:YAG laser capsulotomy after AcrySof IOL implantation and who had at least 3 months follow-up (range, 3-92 months; median, 25 months). The effectiveness of laser treatment was evaluated in terms of the need for repeat laser procedures or intraocular surgery to clear the visual axis. RESULTS: Fifty-one eyes (70%) maintained a clear visual axis after a single Nd:YAG procedure, 10 eyes (84% cumulative) after 2 Nd:YAG procedures, and another 3 eyes (88% cumulative) after 3 Nd:YAG procedures. Six eyes (8%) required pars plana membrane removal to clear the visual axis, whereas 3 eyes (4%) continue to need treatment. Life table analysis showed that the probability of continuing success after 24 months with a single Nd:YAG procedure is 68% (95% confidence interval 53-83%). In younger children (age<4 years), this rate probability was lower than in older children (35% vs. 74%; P=0.022). Two eyes developed mild transient elevated intraocular pressure. In 1 eye, the IOL was dislocated and replaced. DISCUSSION: Nd:YAG laser capsulotomy is an acceptable option for the management of PCO after AcrySof IOL implantation in children and produces complications infrequently.

Acrylic Resins↗
PubMed2006

Generation of three-dimensional hepatocyte/gelatin structures with rapid prototyping system.

Using rapid prototyping technology, three-dimensional (3D) structures composed of hepatocytes and gelatin hydrogel have been formed. This technique employs a highly accurate 3D micropositioning system with a pressure-controlled syringe to deposit cell/biomaterial structures with a lateral resolution of 10 microm. The pressure-activated micro-syringe is equipped with a fine-bore exit needle for which a wide variety of 3D patterns with different arrays of channels (through-holes) were created. More than 30 layers of a hepatocyte/gelatin mixture were laminated into a high spacial structure using this method. The laminated hepatocytes remained viable and performed biological functions in the construct for more than 2 months. The rapid prototyping technology offers potential for eventual high-throughout production of artificial human tissues or organs.

Animals↗
PubMed2006

A PEGylated fibrin patch for mesenchymal stem cell delivery.

A potential therapy for myocardial infarction is to deliver isolated mesenchymal stem cells (MSCs) to the infarcted site. A key issue with this technology is the development of a suitable system for MSC delivery. Our delivery system of interest is a fibrin-based patch used to entrap cells during polymerization. This delivery vehicle has many advantages; however the mechanical properties and the limited capacity for tailoring cell response may restrict its application. We have developed a PEGylated fibrin patch for MSC transplantation by modifying fibrinogen (Fgn) with the benzotriazole carbonate derivative of PEG to create secondary crosslinking. In this study, the chemical PEGylation of fibrinogen was verified by both amine group quantification and SDS-PAGE. The clotting characteristics and physical properties were compared between the fibrin patch and PEGylated fibrin patch. After seeding with porcine MSCs, the cell viability, morphology, and motility in the novel patch were observed. Phenotypic changes in the embedded MSCs were examined using immunohistochemistry and RT-PCR. The optimal molar ratio (PEG:Fgn = 10:1) was determined for loading MSCs in vitro into the PEGylated fibrin patch. The results suggest that our PEGylated fibrin patch increases MSC viability. Furthermore, the PEGylated fibrin causes phenotypic changes in MSCs consistent with endothelial cells.

Animals↗
PubMed2006

Functional and bioenergetic consequences of AT1 antagonist olmesartan medoxomil in hearts with postinfarction LV remodeling.

The structural left ventricular (LV) remodeling and contractile dysfunction of hearts with postinfarction LV remodeling are benefited by angiotensin II type 1 receptor (AT1) blocker. However, the myocardial bioenergetic consequences of AT1 blocker in these hearts are not known. To investigate, we used a porcine model of postinfarction LV remodeling produced by ligation of the left circumflex coronary artery. After infarction, 7 pigs received olmesartan medoxomil (2 mg/kg) for comparison against 9 untreated and 10 normal pigs. Measurements of hemodynamics, myocardial perfusion, and myocardial bioenergetics were taken 7 weeks postinfarction. The treated group had an LV-to-body weight ratio significantly lower than the untreated group (2.69 +/- 0.70, 2.96 +/- 0.51, 3.66 +/- 0.60 g/kg for control, treated, and untreated groups, respectively). The untreated group had a mean aortic pressure significantly higher than the control (73 +/- 16, 86 +/- 14, and 94 +/- 20 mm Hg, respectively). The subendocardial phosphocreatine-to-ATP ratios of the treated group were significantly higher than that of the untreated group. The untreated group, but not the treated group, had significant reductions in mitochondrial F0F1-ATPase subunits compared with controls. Congestive heart failure as evidenced by significant ascites (100 to 2000 mL) developed in 4 of the 9 untreated animals, but was absent in the treated group. Animals with heart failure demonstrated reductions in both mitochondrial F0F1-ATPase expression and myocardial high-energy phosphate levels. Thus, severe LV dysfunction and accompanying abnormal myocardial bioenergetic phenotype were prevented by the AT1 antagonist olmesartan medoxomil.

Angiotensin II Type 1 Receptor Blockers↗