Biomedical subjects

Ping Hu

Publications and source records attributed to Ping Hu.

At least 73 records · Page 4Linked to original sources

PubMed2004

[Biocompatibility of p(3HB-co-3HH) and marrow mesenchymal stem cells].

OBJECTIVE: To investigate the biocompatibility of p(3HB-co-3HH) and marrow mesenchymal stell cells (MSCs). METHODS: MSCs were inoculated to p(3HB-co-3HH), and then cultured for 2-4 weeks in vitro and embedded for 2 weeks in vivo. The growth, proliferation, morphology and phenotype properties of MSCs were observed by use of phase contrast microscope, electron microscope, HE staining and staining of type I collagen. RESULTS: p(3HB-co-3HH) had good compatibility. The inoculated MSCs could be well-distributed, attached well and obtain the phenotype of MSCs in p(3HB-co-3HH). After osteogenic inducer were added, MSCs differentiated to osteoblasts and secreted matrix. Type I collagen was stained positively by immunohistochemical techenique. CONCLUSION: The above results demonstrate that there is satisfactory biocompatibility between p(3HB-co-3HH) and MSCs.

3-Hydroxybutyric Acid↗

PubMed2004

Single photon emission computer tomography of dopamine transporters in monkeys and humans with 99mTc-TRODAT-1.

BACKGROUND: The diagnosis of Parkinson's disease is presently based on non-specific symptoms. However, radionuclide dopamine transporters imaging can provide specific diagnostic tool for Parkinson's disease. This study was designed to investigate the effects of imaging of dopamine transporters with 99mTc-TRODAT-1 in early diagnosis or differential diagnosis of Parkinson's disease. METHODS: Nine normal monkeys were used to establish N-methyl-4-phenyl-1, 2, 3, 6-tetra-hydropyridine (MPTP) hemi-Parkinsonian animal models, and they were subjected to imaging. Twenty-nine patients with Parkinson's disease, 12 age-matched healthy volunteers, and 18 age-matched patients with Parkinson's syndrome were investigated. Single photon emission computer tomography (SPECT) was performed 3 hours after intravenous injection of 740 MBq 99mTc-TRODAT-1. Striatum specific uptake of 99mTc-TRODAT-1 was calculated according to the ratio of striatum (ST) to cerebellum (CB) in dopamine transporters uptake. RESULTS: In normal monkeys, bilateral ratio of ST/CB was 2.34 +/- 0.41. After the injection of MPTP, uptake rate of 99mTc-TRODAT-1 at damaged region was much lower than that at the contralateral region, resulting in a significant difference in the ratio of ST/CB (right: ST/CB = 1.73 +/- 0.35; left: ST/CB = 1.90 +/- 0.30), especially in hemi-Parkinsonian model monkeys (right: ST/CB = 1.29 +/- 0.17; left: ST/CB = 1.80 +/- 0.33). The ratios of ST/CB were 1.57 +/- 0.17 and 1.61 +/- 0.14 for the right and left respectively in the healthy volunteers, 1.04 +/- 0.29 and 1.06 +/- 0.30 in the age-matched patients with Parkinson's disease, and 1.56 +/- 0.17 and 1.59 +/- 0.18 in the age-matched patients with Parkinson's disease syndrome. A significant difference was noted between group of Parkinson's disease, normal controls and Parkinson's disease syndrome. CONCLUSION: The results suggest that 99mTc-TRODAT-1 dopamine transporters SPECT has clinical application value in early diagnosis or differential diagnosis of Parkinson's disease.

Adult↗

PubMed2004

[Re-growth of induced-osseous tissue encapsulated in muscular fasciae for prefabrication of an osteo-musculo-cutaneous flap].

OBJECTIVE: To improve the survival of mesenchymal stem cells (MSCs) for prefabrication of an osteo-musculo-cutaneous flap. METHODS: In a mouse model, the compound of MSCs and p(3HB-co-3HH) were embeded in the latissimus dorsi muscle as an experimental group and the muscle pocket of the buttock as the control. The examinations of the HE staining, hybridization in situ of osteonectin mRNA and Von kossa staining were used to evaluate the results. RESULTS: The expression of osteonectin mRNA and the Von kossa staining showed that the latissimus dorsi muscle group was superior to the control in 2 weeks and 4 weeks after the surgery in vivo. CONCLUSION: The results indicate that the above-mentioned technique may be a good alternative for the prefabrication of the osteo-musculo-cutaneous flap.

Animals↗

PubMed2004

[Transplantation of adrenocortical cells in allorat using porous PHB as cell carrier].

This experiment was designed to investigate the feasibility of transplanatation of using porous PHB as cell carrier for the transplanatation of adrenocortical cells. Adrenocortical cells from rat adrenal gland were separated and cultured in vitro. The effect of PHB on the proliferation and secretory function of adrenocortical cells were evaluated by MTT and RIA methods. Then adrenocortical cells were seeded into porous PHB. After the cells were cultured in vitro for about seven days, they were implanted into the rats having undergone bilateral adrenalectomy. The changes of blood corticosterone and aldosterone and the local histological changes in these rats were observed. Adrenocortical cells were able to grow and survive on PHB. No effect on the proliferation and secretory function of adrenocortical cells were observed. Most bilateral adrenalectomized rats bearing the transplanted adrenocortical cells within PHB (study group) survived longer than did the adrenalectomized rats in control group. The blood corticosterone level and aldosterone level of study group were higher than those of control group. It was found that PHB has no effects on the survival, proliferation and secretory function of adrenocortical cells. Adrenocortical cells within PHB can survive a period of time and can secrete corticosterone and aldosterone which can meet the needs of the adrenalectomized rats. PHB can degrade slowly in vivo. It is feasible to perform transplantation of adrenocortical cells using porous PHB as cell carrier.

Adrenal Cortex↗

PubMed2004

[Multiple nonlinear statistical method of population genetic structure based on the allelic polymorphism data].

The distribution and structure of the allelic polymorphism data are analyzed and it is pointed out that the distribution of allelic polymorphism data reveals the characteristic of closed data (also named as compositional data or data of constant sum). It is interpreted that the correlation structure of the allelic polymorphism data contains null correlations introduced by "closure" and the statistical distribution of the data is not normal because of its constant row sum, which resulted in great difficulties in analyzing the data with traditional multiple linear statistical methods such as principal component analysis, factor analysis, cluster analysis and canonical correlation analysis. Based on the theory of compositional data analysis proposed by Aitchison in 1982, a multiple nonlinear statistical method originating from the "logratios" approach to the statistical analysis of compositional data is put forward in this paper. As an example, the "logratios" method was used to analyze the genetic structure of TH01 polymorphic loci in Chinese population and the results were compared with those of multiple linear methods such as component principal. It is concluded that the "logratios" multiple nonlinear principle component analysis is a better method with the virtue of sensitivity and specificity for analyzing the genetic structure of population from the data of allelic polymorphism.

Alleles↗

PubMed2004

[Fabrication of laryngeal cartilage by means of tissue engineering technique].

OBJECTIVE: To explore the method of fabricating tissue engineered laryngeal cartilage. METHODS: The rib and articular cartilage of infant New Zealand white rabbits were harvested in sterile condition. The chondrocytes were separated by collagenase digestion and cultured in vitro for 3 passage. Serial steps of solution casting, extrusion molding and particulate leaching were used to make larynx-shaped biomaterial models with poly(3-hydroxybutyrate-co-3-hydroxyhexanoate, PHBHH). The chondrocytes were seeded onto PHBHH scaffolds to form cell-PHBHH composites, which were subsequently in vitro for one week. After that, the measure of filling inner space of cell-PHBHH composites together with wrapping total composites using either greater omentum (n = 9) or fascia flap and muscle (also n = 9) in experimental groups was taken to implant the larynx-shaped biomaterial models seeded with chondrocytes into the belly and the back of adult New Zealand white rabbits. Control groups (every group n = 3) were the same measure as experimental groups but without chondrocyte on PHBHH scaffolds. Finally, morphological observation, HE staining & special staining and immunohistochemical test were conducted to assess cartilage regeneration and its shape at different period following implantation. RESULTS: The rate of viable cell in the final cell suspension was (93 +/- 2)% after well-controlled prolongation of digestion trypsin. Similar to that by traditional procedures (94 +/- 2)% (P > 0.05). The larynx-shaped PHBHH models with edges and corners of laryngeal cartilage made by us appeared to be hollow half-trumpet shape and its porosity was more than 90%. It showed that chondrocytes equally attached to the surface of porous PHBHH and filled within porousness with scanning electron microscopic examination. Tissue engineered larynx-shaped specimens could alternatively be harvested with the above mentioned two different implantation measures. The specimens presented to be similar to that before implantation in gross shape. It was demonstrated to be cartilaginous tissue through histological and immunohistochemical examination. Furthermore, There was nearly no difference between two kinds of tissue engineered laryngeal cartilage with two measures of implantation in morphology and histology. CONCLUSIONS: The regeneration of tissue engineered cartilage in vivo is not influenced by the chondrocytes harvested by improvement of well-controlled prolonged digestion with trypsin during in vitro cell culture. It seems that PHBHH may be used as scaffold in cartilage tissue engineering and wrapping together with filling method with either greater omentum or fascia flap and muscle is appropriate for fabricating tissue engineered laryngeal cartilage.

Animals↗

PubMed2004

The inhibitory effects of mouse ICOS-Ig gene-modified mouse dendritic cells on T cells.

The main approach to reduce graft rejection has been focused on the development of immunosuppressive agents at present. Although these strategies have reportedly reduced graft rejection, there has been a reciprocal increase in more severe immunosuppression and lethal infections, as well as severe side effects. Blockade of costimulatory T cell response has been proved as one of useful strategies to reduce graft rejection. Furthermore, it has been shown that infusion of dendritic cells (DCs) with a potent negative regulatory ability for T cells could prolong allograft survival. In this study mouse DCs (mDCs) were transfected with the recombinant plasmid pcDNA3.0 containing mouse inducible costimulator-Ig (mICOS-Ig) cDNA by electroporation. The transient expression of mICOS-Ig in mDC could be detected by ELISA and SDS-PAGE. Mouse ICOS-Ig fusion protein expressed in mDC and mICOS-Ig gene-modified mDC could inhibit lymphocyte proliferation in mixed lymphocyte culture (MLC) in vitro. Furthermore, mICOS-Ig gene-modified mDC could inhibit lymphocyte proliferation in recipient mice. These results suggested that mICOS-Ig gene-modified mDC exerted inhibitory effects on T cells, and might be suitable for treatment or prevention of graft rejection and immunopathologic diseases.

Animals↗

PubMed2004

FADDdel-GFP modified mouse insulinoma cells counteract the cytotoxicity of reactive T cells.

IDDM results from pancreatic beta cell destruction by islet-reactive T cells, a process that involves beta cell apoptosis. Fas-FasL pathway plays a major role in pancreatic beta cell death. Fas-associated death domain protein (FADD), the component of the tumor necrosis factor receptor type 1 (TNFR1) and Fas signaling complexes, is involved in TNFR1- and Fas-induced apoptosis. Inhibiting the function of FADD will lead to blocking downstream apoptosis signal, which protects pancreatic beta cells from destruction by Fas-FasL pathway. In this study we constructed eukaryotic expressing vector of fusional protein FADDdel-GFP named pFADDdel-GFP. After pFADDdel-GFP was transfected into NIT, the expression of FADDdel-GFP in NIT was detected by fluorescence microscopy and the resistance of NIT transfected with pFADDdel-GFP to cytotoxicity mediated by special T cells was detected by FACS and MTT. The results showed that NIT modified by pFADDdel-GFP obviously resisted cytotoxicity mediated by special T cells. Therefore, it may be useful in the prevention or treatment of IDDM by intervening Fas-FasL pathway.

Adaptor Proteins, Signal Transducing↗

PubMed2003

Selective reactions of cutaneous and muscle afferent neurons to peripheral nerve transection in rats.

To determine whether peripheral nerve injury has similar effects on all functional types of afferent neuron, we retrogradely labeled populations of neurons projecting to skin and to muscle with FluoroGold and lesioned various peripheral nerves in the rat. Labeled neurons were counted after different periods and related to immunohistochemically identified ectopic terminals and satellite cells in lumbar dorsal root ganglia. After 10 weeks, 30% of cutaneous afferent somata labeled from transected sural nerves had disappeared but, if all other branches of the sciatic nerve had also been cut, 60% of cutaneous neurons were lost. Small-diameter sural neurons preferentially disappeared. In contrast, the number of muscle afferent somata was not affected by transection of various nerves. p75 was downregulated in axotomized cutaneous neurons but in not axotomized muscle neurons. Conversely, p75 was upregulated in satellite cells around cutaneous but not muscle neurons. Consistent with this, perineuronal rings containing tyrosine hydroxylase, calcitonin gene-related peptide, galanin, or synaptophysin were formed preferentially around cutaneous neurons. Selective lesions of predominantly cutaneous nerves triggered the formation of rings, but none were detected after selective lesions of muscle nerves. We conclude that cutaneous neurons are both more vulnerable and more associated with ectopic nerve terminals than muscle neurons in dorsal root ganglia after transection and ligation of peripheral nerves.

Animals↗

PubMed2003

Minimally invasive aortic banding in mice: effects of altered cardiomyocyte insulin signaling during pressure overload.

We developed a minimally invasive method for producing left ventricular (LV) pressure overload in mice. With the use of this technique, we quickly and reproducibly banded the transverse aorta with low surgical morbidity and mortality. Minimally invasive transverse aortic banding (MTAB) acutely and chronically increased LV systolic pressure, increased heart weight-to-body weight ratio, and induced myocardial fibrosis. We used this technique to determine whether reduced insulin signaling in the heart altered the cardiac response to pressure overload. Mice with cardiac myocyte-restricted knockout of the insulin receptor (CIRKO) have smaller hearts than wild-type (WT) controls. Four weeks after MTAB, WT and CIRKO mice had comparably increased LV systolic pressure, increased cardiac mass, and induction of mRNA for beta-myosin heavy chain and atrial natriuretic factor. However, CIRKO hearts were more dilated, had depressed LV systolic function by echocardiography, and had greater interstitial fibrosis than WT mice. Expression of connective tissue growth factor was increased in banded CIRKO hearts compared with WT hearts. Thus lack of insulin signaling in the heart accelerates the transition to a more decompensated state during cardiac pressure overload. The use of the MTAB approach should facilitate the study of the pathophysiology and treatment of pressure-overload hypertrophy.

Animals↗

PubMed2003

A minimal RNA polymerase III transcription system from human cells reveals positive and negative regulatory roles for CK2.

In higher eukaryotes, RNA polymerase (pol) III is known to use different transcription factors to recognize three basic types of promoters, but in no case have these transcription factors been completely defined. We show that a highly purified pol III complex combined with the recombinant transcription factors SNAP(c), TBP, Brf2, and Bdp1 directs multiple rounds of transcription initiation and termination from the human U6 promoter. The pol III complex contains traces of CK2, and CK2 associates with the U6 promoter region in vivo. Transcription requires CK2 phosphorylation of the pol III complex. In contrast, CK2 phosphorylation of TBP, Brf2, and Bdp1 combined is inhibitory. The results define a minimum core machinery, the ultimate target of regulatory mechanisms, capable of directing all steps of the transcription process-initiation, elongation, and termination-by a metazoan RNA polymerase, and suggest positive and negative regulatory roles for CK2 in transcription by pol III.

ATPases Associated with Diverse Cellular Activitie↗

PubMed2003

Distinct functional types of macrophage in dorsal root ganglia and spinal nerves proximal to sciatic and spinal nerve transections in the rat.

Inflammation proximal to a peripheral nerve injury may be responsible for ectopic discharge and/or death of sensory neurones, factors thought to contribute to the development and/or maintenance of neuropathic pain. Here, ED1+, ED2+ and major histocompatibility complex class II (MHC II)+ macrophages in dorsal root ganglia (DRGs) and spinal nerve roots have been compared quantitatively in adult rats following transection of one sciatic or one spinal nerve, using double labelling immunohistochemistry. In control DRGs, all ED2+ cells expressed ED1 and some also MHC II. One week after either lesion, the ED2+ cells changed negligibly, except that all expressed MHC II. ED1+ and MHC II+ cell density increased markedly, with cells expressing MHC II alone (the majority), ED1/MHC II or rarely ED1 alone. In the spinal roots, ED1+ and MHC II+ cell density increased less after sciatic than after spinal nerve transection when ED1+ foamy cells were prominent. All ED2- macrophages were aggregated with T lymphocytes around blood vessels at 1 week or around isolated somata at later stages. ED1+ cell density declined more rapidly than MHC II+ cell density. Within the DRG, the debris of retrogradely labelled neurones appeared in ED2+ cells and a small proportion of MHC II+ cells that contained ED1. The data suggest that (i) resident ED2+ macrophages do not proliferate but are phagocytic and (ii) of ED1+ and MHC+ monocytes invading from the blood, only ED1+/MHC II+ cells are phagocytic. Four functional subtypes of macrophage within the DRGs were distinct from ED1+ foamy cells that phagocytosed myelin after spinal nerve transection.

Animals↗

PubMed2003

Cloning and characterization of a novel gene, SHPRH, encoding a conserved putative protein with SNF2/helicase and PHD-finger domains from the 6q24 region.

Here we report the identification of a novel transcript containing SNF2, PHD-finger, RING-finger, helicase, and linker histone domains mapping to the q24 band region of human chromosome 6. These domains are characteristic of several DNA repair proteins, transcription factors, and helicases. We have cloned both human and mouse homologs of this novel gene using interexon PCR and RACE technologies. The human cDNA, termed SHPRH, is 6018 bp and codes for a putative protein of 1683 amino acids. The mouse cDNA, termed Shprh, is 7225 bp and codes for a putative protein of 1616 amino acids. The deduced amino acid sequences of the two proteins share 86% identity. Both genes are expressed ubiquitously, with a transcript size of approximately 7.5 kb. Mapping of this gene to 6q24, a region reported to contain a tumor suppressor locus, prompted us to evaluate SHPRH by mutation analysis in tumor cell lines. We have identified one truncating and three missense mutations, thus suggesting SHPRH as a possible candidate for the tumor suppressor gene.

Amino Acid Sequence↗

PubMed2003

Leveraging the mouse genome for gene prediction in human: from whole-genome shotgun reads to a global synteny map.

The availability of draft sequences for both the mouse and human genomes makes it possible, for the first time, to annotate whole mammalian genomes using comparative methods. TWINSCAN is a gene-prediction system that combines the methods of single-genome predictors like GENSCAN with information derived from genome comparison, thereby improving accuracy. Because TWINSCAN uses genomic sequence only, it is less biased toward highly and/or ubiquitously expressed genes than GENEWISE, GENOMESCAN, and other methods based on evidence derived from transcripts. We show that TWINSCAN improves gene prediction in human using intermediate products from various stages of the sequencing and analysis of the mouse genome, from low-redundancy, whole-genome shotgun reads to the draft assembly and the synteny map. TWINSCAN improves on the prior state of the art even when alignments from only 1X coverage of the mouse genome are available. Gene prediction accuracy improves steadily from 1X through 3X, more slowly from 3X to 4X, and relatively little thereafter. The assembly and the synteny map greatly speed the computations, however. Our human annotation using the mouse assembly is conservative, predicting only 25,622 genes, and appears to be one of the best de novo annotations of the human genome to date.

Animals↗

PubMed2003

[Binding characteristics of new synthesized opioid receptor ligands to cloned mu opioid receptors stably expressed in CHO cell].

OBJECTIVE: To determine the affinity of new opioid receptor ligands to cloned mu opioid receptors stably expressed in CHO cell. METHODS: The binding characteristics of the opioid ligand [3H] diprenorphine (3H-dip) were studied by cellular biological techniques and radioligands binding in cloned mu opioid receptors stably expressed in CHO cells in saturation binding experiments, and were followed by competition binding experiments with a variety of new synthesized opioid receptor ligands. RESULTS: The Kd and Bmax of [3H] diprenorphine bound to mu receptors were 1.06 nmol/L and 930 fmol/mg protein, respectively. Competition binding experiments revealed that ligand 3# and 12# displayed much higher affinity than DAMGO and Morphine for the cloned mu opioid receptor. However, the affinities of ligands 2#, 6#, 8# and 9# were lower than DAMGO and Morphine. CONCLUSION: The present results suggest that the new ligands 3# and 12# have higher affinity to mu opioid receptors. However, ligands 2#, 6#, 8# and 9# have lower affinity to mu opioid receptors.

Animals↗

PubMed2003

[Studies on stability of chlorogenic acid in extract of Flos lonicerae].

OBJECTIVE: To investigate the stability of chlorogenic acid in extract of flos lonicerae in different conditions. METHOD: The stability of chlorogenic acid in extract of flos lonicerae in phosptat buffe with different pH values, methanol, ethanol and different base solutions(Ca(OH)2 and NaOH) was investigated by the classical isothermal method. RESULT: The experiments showed the chlorogenic acid in extract of flos lonicerae was more stable in acidic water than in basic water. It was stable in these organic solutions and base solution[Ca(OH)2]. CONCLUSION: In different conditions, the stability of chlorogenic acid in extract of flos lonicerae was different. It provided a reference to the extraction and analysis of chlorogenic acid and production of chlorogenic acid preparation.

Calcium Hydroxide↗

PubMed2002

Uroplakin IIIb, a urothelial differentiation marker, dimerizes with uroplakin Ib as an early step of urothelial plaque assembly.

Urothelial plaques consist of four major uroplakins (Ia, Ib, II, and III) that form two-dimensional crystals covering the apical surface of urothelium, and provide unique opportunities for studying membrane protein assembly. Here, we describe a novel 35-kD urothelial plaque-associated glycoprotein that is closely related to uroplakin III: they have a similar overall type 1 transmembrane topology; their amino acid sequences are 34% identical; they share an extracellular juxtamembrane stretch of 19 amino acids; their exit from the ER requires their forming a heterodimer with uroplakin Ib, but not with any other uroplakins; and UPIII-knockout leads to p35 up-regulation, possibly as a compensatory mechanism. Interestingly, p35 contains a stretch of 80 amino acid residues homologous to a hypothetical human DNA mismatch repair enzyme-related protein. Human p35 gene is mapped to chromosome 7q11.23 near the telomeric duplicated region of Williams-Beuren syndrome, a developmental disorder affecting multiple organs including the urinary tract. These results indicate that p35 (uroplakin IIIb) is a urothelial differentiation product structurally and functionally related to uroplakin III, and that p35-UPIb interaction in the ER is an important early step in urothelial plaque assembly.

Amino Acid Sequence↗

PubMed2002

Complex karyotypic abnormality in ovarian fibroma associated with Gorlin syndrome.

Nevoid basal cell carcinoma (NBCC) syndrome is an autosomal dominant disorder characterized by distinctive congenital malformations and a variety of benign and malignant neoplasms, including ovarian fibromas. We describe pathologic and cytogenetic findings in a large unilateral ovarian fibroma from a 12-year-old female with NBCC syndrome. The pathologic findings were characteristic for ovarian fibroma, but were unusual for the ovarian fibromas associated with NBCC syndrome because of the absence of calcification, the lack of bilaterality, and the presence of focal hypercellularity. The karyotype of tumor tissue showed complex numerical and structural abnormalities. Although there is frequent loss of heterozygosity of 9q22.3 and mutations in the PTCHgene in Gorlin syndrome, the ovarian fibroma in this case did not have cytogenetically detectable abnormalities of chromosome 9.

Basal Cell Nevus Syndrome↗