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Hongbin Wang

Publications and source records attributed to Hongbin Wang.

13 recordsLinked to original sources
PubMed2006

Preparation of graded zirconia hydroxyapatite composite bioceramic and its immunocompatibility in vitro.

To obtain immunocompatibility, graded zirconia-hydroxyapatite (ZrO(2)-HA) composite bioceramic and simplex ZrO(2)-HA composite bioceramic are prepared. Peripheral blood mononuclear cells (PBMCs) harvested from healthy individuals are cultured with the two ceramic extracts to assess their effect on the transformation of lymphocytes, apoptotic ratio, CD69 expression, and expression of cytokine of TNFalpha and IL-6, with or without phytohemoagglutinin (PHA)-stimulated cells. Ceramic extracts did not activate the resting lymphocytes, whereas the response of the PHA-stimulated cells was significantly modified. The PBMCs activated by graded ZrO(2)-HA composite bioceramic is noticeably smaller than that by simplex ZrO(2)-HA composite bioceramic; these results, however can only be seen under the amplified effect of PHA-stimulation.

Animals↗
PubMed2006

The zebrafish homologue of mammalian chimerin Rac-GAPs is implicated in epiboly progression during development.

In this paper, we report an in vivo model for the chimerins, a family of Rac GTPase-activating proteins (Rac-GAPs) that are uniquely regulated by the lipid second messenger diacylglycerol and have been implicated in the control of actin dynamics, migration, and proliferation. We cloned the zebrafish homologue of mammalian alpha2-chimerin (chn1) and determined that it possesses Rac-GAP activity and a C1 domain with phorbol ester/diacylglycerol-binding capability. chn1 morpholino knockdown embryos exhibit severe abnormalities, including the development of round somites, lack of yolk extension, and a kinked posterior notochord. These zebrafish morphants show Rac hyperactivation and progress faster through epiboly, leading to tailbud-stage embryos that have a narrow axis and an enlarged tailbud with expanded bmp4 and shh expression. Phenotypic rescue was achieved by mRNA microinjection of chn1 or an active chimerin Rac-GAP domain into the yolk syncytial layer but not by a chn1 mutant deficient in Rac-GAP activity, suggesting that the lack of chn1 Rac-GAP activity in the yolk syncytial layer was causative of the misbalance in morphogenetic movements. Our results reveal a crucial role for chn1 in early development and implicate Rac as a key regulator of morphogenetic movements during zebrafish epiboly.

Animals↗
PubMed2006

A subgroup of first-degree relatives of Crohn's disease patients shows a profile of inflammatory markers in the blood which is more typical of Crohn's disease patients than of normal individuals.

INTRODUCTION: Family member with IBD is the greatest risk factor for developing the disease. The hematological profileof first-degree relatives (FDRs) of Crohn's disease (CD) patients was studied in order to identify healthy FDRs at risk to develop disease. MATERIALS AND METHODS: Thirty CD patients, 90 FDRs, and 28 non-related individuals (controls) were enrolled. Hematological profile and C-reactive protein were determined. RESULTS: All hematological parameters were significantly different in CD patients compared to controls, with significantly higher levels of CRP, WBC, PMN, MONO, and PLT and lower Hb and lymphocyte count. The hematological profile of FDRs showed values between the controls and CD patients with ten FDRs that their parameters matched those of CD patients and significantly different from other FDRs. This group was defined as high-risk relatives (HRRs). CONCLUSIONS: Analysis of the hematological profile and CRP level might be proven as a fast, reliable, and less money-consuming tool to identify FDRs with a probable increased risk to develop the disease.

Adolescent↗
PubMed2006

The involvement of the inferior parietal cortex in the numerical Stroop effect and the distance effect in a two-digit number comparison task.

The neural mechanism of number representation and processing is currently under extensive investigation. In this functional magnetic resonance imaging study, we designed a number comparison task to examine how people represent and compare two-digit numbers in the brain, and whether they process the decade and unit digits in parallel. We manipulated the decade-unit-digit congruency and numerical distance between the pairs of numbers. We observed both Stroop-like interference and the distance effect in the participants' performance. People responded more slowly to incongruent pairs of numbers and pairs of a smaller distance. The inferior parietal cortex showed common and distinct patterns of activation for both attentional selection and number comparison processes, and its activity was modulated by the Stroop-like interference effect and the distance effect. Taken together, these results support both parallel and holistic comparison of two-digit numbers in the brain.

Adolescent↗
PubMed2006

[Preparation of graded zirconia-hydroxyapatite composite bioceramic and its immunocompatibility in vitro].

Graded Zirconia-hydroxyapatite composite bioceramic and simplex Zirconia-hydroxyapatite composite bioceramic were produced, and the extractes of these two of materials were made to evaluate their immunocompatibility. Scanning electron microscope (SEM) was used to detect the character of the surface of the graded composite bioceramic. Holding and without holding phytohemagglutinin (PHA), proliferation and activation of peripheralblood monocytes(PBMCs) cultured in the two extracts were studied. Cultured in PHA after 72 hours, the proliforation rate of the graded composite group was significantly higher than the simplex composite group (P < 0.01). There was no difference of apoptosis of PBMCs of the two groups (P > 0.05). Cultured in PHA after 24 hours, the ratio of CD3/CD69 positive PBMCs of the simple composite group was significantly higher than that of the graded composite material group (P < 0.01). The numbers of PBMCs activated by the graded composite material group were less than that of the simply composite material group and the technique of graded composite will be helpful to improve its immunocompatibility.

Adult↗
PubMed2005

Molecular evidence for asymmetric evolution of sister duplicated blocks after cereal polyploidy.

Polyploidy (genome duplication) is thought to have contributed to the evolution of the eukaryotic genome, but complex genome structures and massive gene loss during evolution has complicated detection of these ancestral duplication events. The major factors determining the fate of duplicated genes are currently unclear, as are the processes by which duplicated genes evolve after polyploidy. Fine-scale analysis between homologous regions may allow us to better understand post-polyploidy evolution. Here, using gene-by-gene and gene-by-genome strategies, we identified the S5 region and four homologous regions within the japonica genome. Additional phylogenomic analyses of the comparable duplicated blocks indicate that four successive duplication events gave rise to these five regions, allowing us to propose a model for this local chromosomal evolution. According to this model, gene loss may play a major role in post-duplication genetic evolution at the segmental level. Moreover, we found molecular evidence that one of the sister duplicated blocks experienced more gene loss and a more rapid evolution subsequent to two recent duplication events. Given that these two recent duplication events were likely involved in polyploidy, this asymmetric evolution (gene loss and gene divergence) may be one possible mechanism accounting for the diploidization at the segmental level.

Chromosomes, Artificial, Bacterial↗
PubMed2005

The effect of external representations on numeric tasks.

This article explores the effect of external representations on numeric tasks. Through several minor modifications on the previously reported two-digit number comparison task, we obtained different results. Rather than holistic comparison, we found parallel comparison. We argue that this difference was a reflection of different representational forms: The comparison was based on internal representations in previous studies but on external representations in our present study. This representational effect is discussed under a framework of distributed number representations. We propose that in numerical tasks involving external representations, numbers should be considered as distributed representations, and the behaviour in these tasks should be considered as the interactive processing of internal and external information through the interplay of perceptual and cognitive processes. We suggest that theories of number representations and process models of numerical cognition should consider external representations as an essential component.

Cognition↗
PubMed2005

Object location memory: the interplay of multiple representations.

This article reports three experiments in which the representational nature of human object location memory was studied. The results show that multiple frames of reference can be used to encode the spatial relationships among objects. Depending on their dominancy, availability, and validity, these multiple representations interact to determine memory performance. Specifically, representations that are automatically encoded and extensively practiced are more dominant, and their availability improves performance when they are valid. On the other hand, when the dominant representations are available but invalid, people may have to resort to the less dominant representations. As a result, the availability of these dominant but invalid representations can actually hurt performance, due to interference. If these interfering representations are eliminated, the performance is again improved. The implications of these findings for general human spatial cognition are discussed.

Adult↗
PubMed2005

[Humus composition of black soil and its organo-mineral complexes under different fertility level].

Determinations by Kumada method showed that with the improvement of black soil fertility, the free and combined humus contents in soil and its different size organo-mineral complexes increased, but the humification degree of free humus decreased, which was more obvious in silt and fine sand size complexes. The organic carbon content in complexes, humus extraction rate, free humus content, and humification degree of free humic acid decreased with the increasing particle size of complexes. All free humic acids in fertile soil were Rp type, while in unfertile soil, they were Rp and B type. With the increasing particle size of complexes, the type of free humic acids changed in the sequence A type (clay)-->B type (silt)-->Rp type (fine sand). Combined form humic acid mainly belonged to A type, no matter what particle size the complex was. The improvement of soil fertility could make the humification degree of free humus in soil and its complexes decrease, and furthermore, result in type change. In black soil, the type change of free humic acid mainly occurred in silt size complex, and that of combined form humic acid mainly occurred in fine sand size complex.

Fertilizers↗
PubMed2005

[Study on trace component in sex pheromones of Dendrolimus spp].

Two compounds were isolated, as sex pheromone components, from the abdominal tips of the female pine caterpillar moth, Dendrolimus kikuchii. The major component was identified as (Z,E)-5,7-dodecadien-1-yl acetate by gas chromatography and mass spectrometry. There are some difficulties to elucidate the structure of the minor component due to its trace and coelution with other components. The derivatives of alkaline methanolysis and reacetylation of pheromone gland extracts of D. kikuchii were analyzed by high-resolution gas chromatography, which was performed to verify the functional group and stereo isomers of the trace component in the pheromone gland extracts. The trace component was characterized as (Z,E) -5,7-dodecadienol via microchemical reaction. The advantages of the conversion of acetates to corresponding alcohols or of alcohols to the corresponding acetates in identifying the trace component of pheromone gland extracts of D. kikuchii were discussed. The importance of identifying the trace component in pheromone chemical communication system of insects is emphasized.

Animals↗
PubMed2004

Haploinsufficiency for the murine orthologue of Chlamydomonas PF20 disrupts spermatogenesis.

PF20 was first identified in Chlamydomonas rheinhardtii as an essential component of the axoneme central apparatus. We discovered that the mouse Pf20 gene encodes two major transcripts (2.5 and 1.4 kb), which are expressed in different patterns during spermatogenesis, yielding proteins of 71 and 35 kDa, respectively. Both proteins contain contiguous WD repeats in their C termini. The meiotically expressed 71-kDa protein is incorporated into the central apparatus, whereas the 35-kDa protein, which accumulates in postmeiotic male germ cells, is abundant in the nucleus. We disrupted the Pf20 gene domains that encode the C-terminal WD repeats in embryonic stem cells. Highly chimeric mice carrying the mutant Pf20 allele had impaired spermatogenesis with a significant loss of germ cells at the round spermatid stage, in association with disorganization of sperm axoneme structure. The mutated Pf20 allele was never transmitted, indicating that Pf20 haploinsufficiency caused the defects in spermatogenesis. The 35-kDa PF20 protein was shown to bind to meiosis-expressed gene 1 (MEIG1), a chromosome/chromatin-binding protein initially expressed during meiosis but retained in the germ cell nucleus throughout later stages of spermatogenesis. Our findings reveal an essential role for Pf20 in mouse spermatogenesis, sustaining postmeiotic germ cell viability. The different patterns of expression of the two PF20 proteins suggest the possibility that the Pf20 gene has multiple functions during spermatogenesis.

Animals↗
PubMed2004

[Determination of double bond position in conjugated dienes in sex pheromones of Dendrolimus spp].

The dienophile 4-methyl-1,2,4-triazoline-3,5-dione (MTAD) adducts of conjugated diene compounds were used to locate the position of the conjugated double bonds in the parent compounds by high-resolution gas chromatography and electron impact mass spectrometry. Their mass spectra are marked by recognizable molecular ions and abundant diagnostic ions that allow the determination of the diene position. With the identification of the sex pheromone gland extracts of Yunnan pine caterpillar moth Dendrolimus houi as an example, the characteristics of reaction of (E, Z)-5,7-dodecadien-1-ol (E5, Z7-12: OH) and its corresponding aldehyde and acetate with MTAD are discussed. Potential problems in gas chromatographic analysis are also discussed.

Animals↗