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Jian-Hua Liu

Publications and source records attributed to Jian-Hua Liu.

At least 19 recordsLinked to original sources
PubMed2026

Identifying potential therapeutic targets for high myopia via a case-control study and Mendelian randomisation analyses of the human blood metabolome.

BACKGROUND: High myopia increases the risk of pathological ocular changes that may lead to irreversible vision loss. Therefore, the identification of potential biomarkers and therapeutic targets for high myopia is essential for early intervention and prevention. METHODS: Summary statistics for 122 blood metabolites were obtained from three genome-wide association studies (GWASs), whereas data on high myopia were derived from a large GWAS conducted with 50,372 participants from the UK Biobank. Mendelian randomisation (MR) analyses were conducted to assess the causal relationships between blood metabolites and high myopia. A real-world case-control study was conducted to validate the causal associations identified in the MR analyses. RESULTS: The systematic MR analysis identified 5 blood metabolites as both biomarkers and potential drug targets for high myopia, including glutamine (odds ratio [OR]: 0.98, 95% confidence interval [CI]: 0.97-1.00), tyrosine (OR: 0.98; 95% CI: 0.97-0.99), degree of unsaturation (OR: 0.98, 95% CI: 0.98-0.99), docosahexaenoic acid (DHA) (OR: 0.99; 95% CI: 0.98-1.00) and isobutyrylcarnitine (OR: 1.09, 95% CI: 1.05-1.13). The case-control study indicated that the levels of glutamine (OR = 0.76, 95% CI: 0.58-0.98) and tyrosine (OR = 0.72, 95% CI: 0.55-0.94) were significantly associated with a decreased risk of high myopia. CONCLUSIONS: Systematic MR analysis suggested that glutamine, tyrosine, the degree of unsaturation, DHA, and isobutyrylcarnitine may represent promising drug targets for high myopia prevention. Further investigations are needed to validate the therapeutic efficacy and elucidate the underlying mechanisms involved.

Humans↗
PubMed2006

Effect of electroacupuncture at Sibai on the gastric myoelectric activities of denervated rats.

AIM: To explore the mechanism of the exciting effects of electro-acupuncture (EA) at Sibai on the gastric myoelectric activities. METHODS: A total of 32 rats were randomly divided into four groups. Through intraperitoneal injection with atropine (the anti-cholinergic agent by blockade of muscarinic receptors), hexamethonium (automatic nerve ganglion-blocking agent) and reserpine (anti-adrenergic agent by depleting the adrenergic nerve terminal of its norepinephrine store), effects of EA at Sibai on the gastric myoelectric activities of the denervated rats were observed. RESULTS: After intraperitoneal injection of atropine and hexamethonium, the average amplitude and ratio of period to time in the phase of high activity of gastric myoelectric slow wave, and the average numbers of the peaks of gastric myoelectric fast wave were significantly decreased (P<0.01, P<0.05, P<0.01), while after intraperitoneal injection of reserpine, the aforementioned three parameters were increased (P<0.01, P<0.05, P<0.01). EA at Sibai point partially relieved the inhibitory effect of atropine and hexamethonium on the gastric myoelectric activities in the rats (P<0.05 or P>0.05). CONCLUSION: Cholinergic and adrenergic nervous systems and autonomic nerve ganglion participate in the peripheral passage of the controlling effects of EA at Foot Yangming Channel on gastrointestinal tract.

Acupuncture Points↗
PubMed2006

Inadvertent germline transmission of AAV2 vector: findings in a rabbit model correlate with those in a human clinical trial.

The risk of germline transmission of vector sequences in humans is a major safety concern, because the enrollment of subjects of reproductive age in early-phase clinical trials of gene transfer continues to increase. In a study of adult men with hemophilia B, adeno-associated virus serotype 2 (AAV2) delivered to the liver via the hepatic artery resulted in unexpected transient vector dissemination to the semen. Here we report that intravenous AAV2 injection in rabbits proved a useful model to assess biologic parameters of vector dissemination to the semen. Detectable vector sequences in semen disappeared in a dose-dependent and time-dependent fashion. AAV infectious particles were present only as long as day 4 after injection and were undetectable thereafter. The kinetics of vector clearance was faster in the semen fractions enriched for motile sperm than in the total semen. In addition, increased frequency of semen sampling accelerated the clearance of vector sequences from semen. Long-term follow-up, spanning hundreds of spermatogenesis cycles, showed that there was no recurrence of detectable vector sequences in semen, thus reducing the probability of inadvertent transduction of early spermatogonia not committed to differentiation at the time of vector injection. We conclude that AAV2 presents minimal germline transmission risk for humans.

Animals↗
PubMed2006

Ubiquinone (coenzyme Q) biosynthesis in Chlamydophila pneumoniae AR39: identification of the ubiD gene.

Ubiquinone is an essential electron carrier in prokaryotes. Ubiquinone biosynthesis involves at least nine reactions in Escherichia coli. 3-octaprenyl-4-hydroxybenzoate decarboxylase (UbiD) is an important enzyme on the pathway and deletion of the ubiD gene in E. coli gives rise to ubiquinone deficiency in vivo. A protein from Chlamydophila pneumoniae AR39 had significant similarity compared with protein ubiD from E. coli. Based on this information, the protein-encoding gene was used to swap its counterpart in E. coli, and gene expression in resultant strain DYC was confirmed by RT-PCR. Strain DYC grew using succinate as carbon source and rescued ubiquinone content in vivo, while ubiD deletion strain DYD did not. Results suggest that the chlamydial protein exerts the function of UbiD.

Amino Acid Sequence↗
PubMed2006

A novel recently evolved gene C19orf24 encodes a non-classical secreted protein.

Secreted proteins play important roles in many crucial biological processes, and can be new agents or targets for drug therapies. Here, we report on the isolation and characterization of a novel human non-classical secreted protein which is encoded by the hypothetical gene C19orf24 (chromosome 19 open reading frame 24). It has no signal peptide, but can still secrete extracellularly despite the presence of the inhibitor brefeldin A (BFA), proving its non-classical secreted protein status. Via subcellular localization using C19orf24 in vivo and transfected pEYFP-Golgi plasmid in Hela cells, C19orf24 was shown not to co-localize in the Golgi apparatus, which suggested that it secretes via a new and unknown pathway. Deglycosylation analysis with PNGase F verified that it has no N-glycosylation modification sites. Via the reverse transcription-PCR method, it was found to be expressed only in the human liver, and preferentially in normal tissue. In addition, C19orf24 was shown to be a recently evolved gene, found only in Homo sapiens and Pan troglodytes. By calculating its synonymous and non-synonymous substitution rate (d (S)/d (N)), we found that it experienced a purifying selection, which suggests that C19orf24 may have a special, irreplaceable biological function in the human organism.

Amino Acid Sequence↗
PubMed2005

Phase evolution, texture behavior, and surface chemistry of hydrothermally derived scandium (hydrous) oxide nanostructures.

Nanostructured scandium hydrous oxides were hydrothermally synthesized at 180 degrees C for 18 h, using NaOH, NH(4)OH, and KOH as the bases. They were characterized by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), N2 adsorption, thermogravimetry and differential thermal analysis (TG-DTA), infrared and Raman spectroscopy, and pyridine adsorption. XRD and TEM measurements showed that the nature and concentration of the bases played key roles in determining the phasic composition, texture behavior (shape and size), and surface chemistry of the hydrothermal products. In addition, the shape evolution of the crystalline products seemed to be closely connected with their crystal structures. As the basicity value was raised from pH 10 to 5 mol L(-1) NaOH (or KOH), alpha-ScOOH nanorods, alpha-ScOOH nanosized hexagonal-like plates, and cubic Sc(OH)3 cubes/cuboids in micrometer size were produced in turn; while within pH 10-12 using NH4OH, gamma-ScOOH nanosized lozenge-like plates were mainly obtained. According to XRD, TEM, and TG-DTA results, all the as-prepared nanostructured ScOOH and micrometric Sc(OH)3 could be converted to cubic Sc2O3 with sustained crystalline shape via calcination at 500 degrees C. Pyridine adsorption revealed the existence of Lewis acid sites on the surfaces of the nanostructured alpha-ScOOH samples and some of their Sc2O3 counterparts calcined at 700 degrees C. The alpha-ScOOH nanorod sample displayed the strongest Lewis acidity among all the samples tested, due to its highest surface area as determined by N2 adsorption. Finally, an olation-oxolation process based on a dissolution/recrystallization mechanism accounts for the formation of various ScOOH polymorphs and Sc(OH)3 with different shapes.

Nanostructures↗
PubMed2005

Induction of mucosal tolerance in Peyer's patch-deficient, ligated small bowel loops.

To explore the requirement for M cells and the Peyer's patch (PP) in induction of oral tolerance and address the potential in vivo role of intestinal epithelial cells as nonprofessional APCs, we have attempted to induce tolerance in mice with ligated small bowel loops without M cells and Peyer's patches. A 2-centimeter section of vascularized small bowel was spliced away from the gut without disruption of the mesenteric attachments. We introduced OVA directly into the lumen of the loop prior to footpad immunization. By excising segments of bowel that contain PPs in some mice and segments without patches in others, we could study the necessity of the M cell and the underlying patch versus epithelial cells in induction of mucosal tolerance. We show that OVA-specific T cell proliferation and serum antibody responses are reduced in mice that have previously been given OVA both in PP-containing loops and in loops without patches. Furthermore, both high- and low-dose tolerance could be induced in the absence of PPs. Low-dose tolerance is associated with bystander suppression and requires IL-10, which indicates active suppression and the induction of regulatory cells. These data suggest that there is a critical role for components of the mucosal immune system other than PPs in antigen sampling and induction of oral tolerance.

Animals↗
PubMed2005

[Preparation and release efficiency of polylactic acid nanoparticle].

BACKGROUND & OBJECTIVE: As a new drug delivery carrier, medical nanoparticle (NP) appears to be very promising and are widely studied. Compare with microparticle, nanoparticle possesses several advantages, such as ultramicroscopic size, could be ingested by the cells after crossing the tissue matrix, and can penetrate the arterial wall and cross the blood-brain barrier. This study was to prepare polylactic acid (PLA) nanoparticle, and observe its morphology, diameter, structure, surface elements, and ability of in vitro drug release. METHODS: The biodegradable PLA was used as the carrier, and 5-fluorouracil (5-FU) was used as the model drug. 5-FU-PLA nanoparticle (5-FU-PLA-NP) was prepared by matrix and ultrasound emulsification. Morphology of 5-FU-PLA-NP was observed under scanning electron microscope; its surface elements were detected by X ray photoelectron spectroscopyû its drug loading (DL), embedding ratio (ER), and ability of in vitro drug release were assessed by ultraviolet spectroscopy. RESULTS: The nanoparticle was uniformly spherical with average diameter of (191+/-17) nm, DL of 15.2%, and ER of 45.6%. The nanoparticle showed sustained release character in the experiment of in vitro drug release: the cumulative drug release rate in analog body fluid was 94.3% at the 10th day. CONCLUSION: PLA-NP may serve as a carrier of 5-FU, and can change the pharmacokinetics of 5-FU, slower down drug release; 5-FU-PLA-NP can be prepared as intravenous injection, and may prolong the in vivo circulation time of 5-FU, so as to play more efficient antitumor effects.

Antimetabolites, Antineoplastic↗
PubMed2005

[Research on the polymorphism of heart fatty acid-binding protein gene in Shanxi pig breeds and their crossbred populations using PCR-RFLP].

The genetic variation in 5' - upstream (Hinf I -RFLP)and the second intron (Hinf I *-RFLP, Hae III-RFLP)of heart fatty acid-binding protein(H-FABP)gene were detected with PCR-RFLP in 286 pigs including Mashen, Shanxi white pig and their crossbred populations. The results showed as follows: (1)Mashen presented only DD genotype while other populations varied,and Mashen crossbred populations had only 2 genotypes(DD, Dd) at the Hae III-RFLP site; (2)At the Hinf I -RFLP site of the 5' -upstream region, the crossbred population of Shanxi white pig and Duroc presented only HH genotype while other populations varied. Frequency of h allele in Mashen was 0.9727. (3)At the Hinf I *-RFLP site of the second intron, only Mashen presented 2 genotypes (BB, Bb), and frequency of B allele was 0.9667. (4)At the Hae III-RFLP and Hinf I *-RFLP sites, all populations were in Hardy-weinberg equilibrium.

Alleles↗
PubMed2004

N-glycosylation is required for efficient secretion of a novel human secreted glycoprotein, hPAP21.

The present study reported the isolation and characterization of a novel human secreted protein, named as hPAP21 (human protease-associated domain-containing protein, 21 kDa), encoded by the hypothetical gene chromosome 2 open reading frame 7 (C2orf7) that contains signal peptide in its N-terminus, without transmembrane domain, except for PA domain in its middle. Western blotting assay indicated that the c-Myc tagged hPAP21 could be secreted into culture medium in the transfected Chinese hamster ovary cells. However, the molecular weights, whatever intracellular (28 kDa) or extracellular (30 kDa) forms, are larger than that of the prediction. To define whether the glycosylation was important process for its secretion, endoglycosidase H (Endo H) and PNGase F (PNG F) were employed to evaluate the effect of glycosylation types on secretion of hPAP21. Interestingly, the extracellular forms were primarily sensitive to PNG F, not Endo H, implying that complex N-glycosylation could be required for the secretion of hPAP21. Furthermore, N-glycosylation of Asn171 was confirmed as potential crucial process for the secretory protein via site-directed mutagenesis assay. All data will be contributed to the understanding of molecular functions of hPAP21.

Amino Acid Sequence↗
PubMed2004

Expression of c-fos in the nucleus of the solitary tract following electroacupuncture at facial acupoints and gastric distension in rats.

Clinical practice has shown that acupuncture at facial acupoints has curative effects on some visceral diseases (especially gastrointestinal diseases). However, the physiological basis has not been clarified yet. In the present study, expression of c-fos in the nucleus of the solitary tract (NTS) of rats following gastric distension and electroacupuncture (EA) at Yangbai (GB14) and Sibai (ST2) as well as Jiache (ST6) acupoints was observed by using immunohistochemistry technique. After EA at the three facial acupoints, c-fos immunoreactive (c-fos-IR) neurons were mainly distributed in the medial (mNTS) and intermediate subnucleus of the NTS, and a few were scatteredly distributed in the dorsalmedial and commissural subnucleus of the NTS. Furthermore, there is difference in the number of c-fos-IR neurons in the mNTS following EA at the three facial acupoints. The number in the EA at ST2 and GB14 group is the highest and the lowest, respectively. Gastric distension induces obviously the expression of c-fos, which is mainly confined in the mNTS. The results suggest that the noxious visceral and somatic afferent information from the stomach and face may converge in the mNTS, which may be involved in the effect of EA at facial acupoints on the gastrointestinal pain.

Acupuncture Points↗
PubMed2004

Mutations in the chloramphenicol acetyltransferase (S61G, Y105C) increase accumulated amounts and resistance in Pseudomonas aeruginosa.

A chloramphenicol acetyltransferase (catB7) gene containing two point mutations, 181A/G and 314A/G, has been recently reported to be a determinant for high-level chloramphenicol resistance phenotype in a Pseudomonas aeruginosa strain PAhcr1. The mutant CATB7 was further characterized in vitro and in vivo to elucidate the molecular basis of high-level resistance. CAT assay demonstrated that the mutant and wild-type recombinant CATB7 had similar specific activities. Dot blotting revealed that the accumulated amounts of CATB7 in P. aeruginosa strains PAO1 and PAhcr1 were proportionate to the respective anti-chloramphenicol level. Site-directed mutagenesis showed that G61S and Y105C contributed synergistically to the PAhcr1 resistance phenotype. It could be proposed that the mutant CATB7 was more structurally stable than catalytically efficient as a chloramphenicol resistance determinant in PAhcr1.

Acetyl Coenzyme A↗
PubMed2004

Effects of electroacupuncture on gastric myoelectric activity and substance P in the dorsal vagal complex of rats.

Acupuncture has been widely applied to treat gastrointestinal diseases in the clinic. However, its precise mechanism remains unknown. In the present study, effects of electroacupuncture (EA) at Zusanli acupoints (ST36) on gastric myoelectric activity and substance P (SP) in the dorsal vagal complex (DVC) were observed. EA at ST36 significantly increased the frequency of slow waves and the frequency of the spike potentials superimposed on the slow waves, which persisted for 90 min after cessation of EA and was completely abolished after bilateral vagotomy. Meanwhile, the mean optical density of SP immunoreactive fibers in the DVC increased following EA. The results suggested that EA at ST36 promoted the gastric myoelectric activity, which was regulated by the vagus, and SP in the DVC may be involved in the excitatory effects. Furthermore, EA had a relative long-term post-effect. We presumed that DVC may be a supraspinal center in the effect of EA on gastric function.

Action Potentials↗
PubMed2004

A universal microarray for detection of SARS coronavirus.

Severe acute respiratory syndrome (SARS) is caused by the SARS coronavirus (SARS-CoV). There are many point mutations among SARS-CoV genome sequences. Previous studies suggested that the mutations are correlated closely with the SARS epidemic. It was found that the bases of six nucleotide positions (nt9404, nt9479, nt19838, nt21721, nt22222 and nt27827) with high-mutation rate have an important relationship with the SARS epidemic. For viral detection as well as genotyping, a universal microarray system was developed that combines RT-PCR and ligase detection reaction (LDR). The Zip Codes attached covalently to a slide remain constant and their complementary Zip Codes (cZip Codes) can be used for tagging target sequence, making the microarrays universal. The discriminating oligonucleotides contain on the 5' end "cZip Codes" that are used to direct LDR product to specific Zip Codes attached covalently to a slide. Since Zip Codes have no homology to either the target sequence or to other sequences in the genomes of both human host and SARS-CoV, there was no false signal due to mismatch hybridizations. 20 samples assayed with the universal microarray were confirmed by DNA sequencing, demonstrating that this microarray system is a promising diagnostic tool for detection and genotyping of the SARS-CoV.

Amino Acid Substitution↗
PubMed2003

[Effects of shouwu-huanjing recipe on human sperm motility and fertility in vitro].

OBJECTIVE: To observe the effect of Shouwu-Huanjing Recipe(SWHJR) medicated serum on human sperm motility and fertility in vitro. METHODS: Human sperm was co-cultured with SWHJR medicated serum in vitro. Human sperm motility was evaluated by computer-assisted semen analysis(CASA). The acrosome reaction and the capability of penetrating zona-free hamster eggs were also observed. RESULTS: The co-cultured SWHJR medicated serum significantly increased the sperm motion velocity(VAP, VCL, VSL) (P < 0.01), the amplitude of lateral head movement (ALH) and the beat frequency of flagellum(BCF), the density of progressive motility sperms (P < 0.05), the acrosome reaction rate(P < 0.001), the fertilization rate(FR) and the fertilization index (FI) in sperm penetration assay(SPA) test (P < 0.01). The stimulation of SWHJR medicated serum occurred in dose-dependent manner. CONCLUSION: SWHJR can improve human sperm motility and fertility.

Acrosome Reaction↗
PubMed2003

[Preparation and application of gel chip].

A new method for manufacturing three-dimensional gel film-coated chips was described in this paper and its advantages were evaluated by its application. A patch of polyacrylamide gel (15mm x 15mm x 20 microm) was fixed on the glass surface with Bind-Silane treatment, then activated by glutaraldehyde. The aldehyde groups in gel provided reactive sites that allowed covalent immobilization of molecules containing amino groups. Oligonucleotides were mechanically spotted by GMS 417 Arrayer. After hybridization with Cy-3 labeled probes, fluorescence signals of perfect binding can be discriminated from mismatched ones. Compared with two-dimensional glass chip, the capacity of oligonucleotides immobilized on gel film-coated chip is over 100 times. And the gel film-coated chip have lower background and shorter hybridization time. Monoclonal antibodys of cytokine IL-4, IL-5, IL-6, IL-7, ANG, I-309 and VEGF were also immobilized on the gel film-coated chips to make protein microarrays. After incubation with serum of breast cancer patients or normal persons, the microarray reacted with biotin-labeled second antibodys of cytokines and Cy-3-labeled streptavidin sequentially. Results show IL-4, IL-5, I-309 and VEGF of patients have higher expression level than normal persons. This kind of protein microarrays can be potentially helpful to clinical diagnosis. Furthermore different oligonucleotides or proteins can be performed in parallel in a single reaction with minimal amount of binding reagents. Such gel film-coated chips can be used widely in the fabrication of oligonucleotides and proteins microarrays.

Acrylic Resins↗