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Gang Huang

Publications and source records attributed to Gang Huang.

At least 19 recordsLinked to original sources
PubMed2025

Hierarchical integration of mNGS, PCR, and other conventional methods for precision TB diagnostics.

UNLABELLED: This study systematically compared the diagnostic accuracy of seven assays for detecting the Mycobacterium tuberculosis complex, including metagenomic next-generation sequencing (mNGS), droplet digital polymerase chain reaction, real-time quantitative polymerase chain reaction, EasyNAT MTC, GeneXpert MTB/RIF, interferon-gamma release assay (IGRA), and acid&#x2012;fast staining (AFS). We try to select appropriate combinations of tuberculosis (TB) detection methods for regions with varying levels of medical resources, based on sensitivity, cost-effectiveness, and operational feasibility. A retrospective analysis was conducted on 141 samples collected from patients with suspected active TB at The First Affiliated Hospital of Sun Yat-sen University between April 2022 and April 2024. Among these samples, there were 100 cases assigned to the case group and 41 cases to the control group, based on the tuberculosis diagnostic criteria. Historical data for Xpert, IGRA, and AFS were collected, and parallel experiments using mNGS, droplet digital PCR (ddPCR), real-time quantitative polymerase chain reaction (RT-qPCR), and EasyNAT were conducted on all samples. Diagnostic performance was evaluated by comparing it with the final clinical diagnoses. Sensitivity, specificity, positive predictive value, negative predictive value, and receiver operating characteristic (ROC) curve analysis were conducted, along with DeLong tests for statistical comparison. Compared with the final clinical diagnosis, mNGS demonstrated the highest sensitivity (100%), followed by IGRA (79.2%), EasyNAT (79.1%), RT-qPCR (78.0%), ddPCR (75.8%), Xpert (75.3%), and AFS (16.7%). The specificity was 100% for both Xpert and AFS, followed by ddPCR (97.6%), RT-qPCR (95.1%), EasyNAT (92.7%), IGRA (72.7%), and mNGS (75.6%). ROC analysis revealed a significantly greater area under the ROC curve for mNGS (0.878) than for ddPCR (0.817, P = 0.031). DeLong tests revealed statistically significant differences in diagnostic performance between mNGS and ddPCR (P < 0.05) and between IGRA and AFS (P < 0.01). mNGS uniquely identified the pathogens involved in co-infection and quantified pathogen-specific sequencing reads. Through a comprehensive evaluation of the diagnostic efficacy, cost-effectiveness, and timeliness of tuberculosis detection methods, we propose corresponding combinations of TB testing approaches for regions with different healthcare resources. For undeveloped regions with limited resources, a combination of AFS +EasyNAT + chest X-ray is recommended. Primary care facilities may additionally employ IGRA + RT-qPCR. Intermediate-level hospitals can incorporate Xpert MTB/RIF for drug resistance testing, while tertiary hospitals or specialized centers should, on the basis of these fundamental tests, utilize mNGS for diagnosis and ddPCR for therapeutic monitoring in patients with complex mixed infections. IMPORTANCE: This study is the first to comprehensively evaluate the diagnostic efficacy, cost-effectiveness, and timeliness of seven TB detection methods in a single-center cohort. Our findings provide actionable solutions for optimizing TB diagnostics in diverse healthcare ecosystems, aligning with the WHO's End TB Strategy to ensure equitable access to rapid diagnostics.

Humans↗
PubMed2007

Oridonin induced apoptosis through Akt and MAPKs signaling pathways in human osteosarcoma cells.

Previous studies have shown that oridonin, a diterpenoid isolated from Rabdosia rubescens, was able to inhibit proliferation and induce apoptosis in several cell types. But the mechanisms remain poorly understood. In this study, we investigated the apoptosis-inducing effect and mechanisms of action of oridonin in human osteosarcoma cells. Our results demonstrated that oridonin induced concentration- and time-dependent suppression of proliferation and activation of apoptosis in U2OS, MG63 and SaOS-2 osteosarcoma cell lines. Oridonin induced the release of cytochrome c accompanied by activation of caspase-9, caspase-3 and cleavage of poly(ADP-ribose) polymerase (PARP). These events were all inhibited by z-VAD-fmk, a universal inhibitor of caspases. Oridonin treatment dephosphorylated constitutively active AKT, FOXO transcription factor, and glycogen synthase kinase 3 (GSK3). In addition, oridonin decreased the phosphorylation of ERK and increased the phosphorylation of p38 MAPK and JNK. Furthermore, oridonin treatment down-regulated the expression of the inhibitor of apoptosis protein(IAP) in osteosarcoma cells. All together, our results suggested that oridonin is able to inactivate Akt and ERK and activate p38 MAPK and JNK signalling pathways in osteosarcoma cells causing the suppression of proliferation and induction of mitochondria- and caspase-dependent apoptosis.

Antineoplastic Agents↗
PubMed2006

Specific covalent immobilization of proteins through dityrosine cross-links.

Dityrosine cross-links are widely observed in nature in structural proteins such as elastin and silk. Natural oxidative cross-linking between tyrosine residues is catalyzed by a diverse group of metalloenzymes. Dityrosine formation is also catalyzed in vitro by metal-peptide complexes such as Gly-Gly-His-Ni(II). On the basis of these observations, a system was developed to specifically and covalently surface immobilize proteins through dityrosine cross-links. Methacrylate monomers of the catalytic peptide Gly-Gly-His-Tyr-OH (GGHY) and the Ni(II)-chelating group nitrilotriacetic acid (NTA) were copolymerized with acrylamide into microbeads. Green fluorescent protein (GFP), as a model protein, was genetically tagged with a tyrosine-modified His6 peptide on its carboxy terminus. GFP-YGH6, specifically associated with the NTA-Ni(II) groups, was covalently coupled to the bead surface through dityrosine bond formation catalyzed by the colocalized GGHY-Ni(II) complex. After extensive washing with EDTA to disrupt metal coordination bonds, we observed that up to 75% of the initially bound GFP-YGH6 remained covalently bound to the bead while retaining its structure and activity. Dityrosine cross-linking was confirmed by quenching the reaction with free tyrosine. The method may find particular utility in the construction and optimization of protein microarrays.

Cross-Linking Reagents↗
PubMed2006

Expression and purification of a soluble B lymphocyte stimulator mutant modified with the T-helper cell epitope.

The DNA encoding soluble B lymphocyte stimulator (134-285 amino acids, sBLyS) mutant with residues 217-224 replaced by two glycines (named msBLyS) was constructed. The sequence encoding a foreign immunodominant T-helper epitope from ovalbumin (OVA) was then coupled to the 5'-end of msBLyS cDNA. After being sequenced, the recombinant DNA was ligated into the prokaryotic expression vector pQE-80L. The recombinant protein was produced in E. coli DH5alpha after induction with IPTG with the yield of more than 40% of total bacterial protein. The recombinant protein was purified with Ni-NTA chromatography and Sepharcryl S200 chromatography to a purity of more than 98%. The BALB/c mice, immunized with the recombinant protein, produced anti-BLyS antibodies at a high level, which indicated that the recombinant BLyS mutant modified with T-helper epitope elicited polyclonal antibodies with cross-reactivity with BLyS in vivo. This recombinant protein may therefore be used as immune inhibitor of BLyS for treating BLyS -associated autoimmune diseases.

Animals↗
PubMed2006

[Analysis of the factors affecting the recurrence of giant cell tumor of bone].

OBJECTIVE: To analyze the clinical factors affecting the recurrence of giant cell tumors (GCT) of bone. METHODS: The complete data of 146 cases with GCT were reviewed. Thirteen clinical factors were analyzed by chi(2) analysis. And the related Campanacci's grade system and Jaffe's grade system was analyzed by Crosstabs analysis. Multipal factors were analyzed by Logistic regression analysis. RESULTS: Nineteen of 146 cases recurred, and recurrence rate was 13.0%. Recurrence rates of curettage and enblock resection groups were 18.8% and 6.3% respectively. And recurrence rates of curettage with or without of extensive procedure were 12.9% and 38.9%. Five cases had lung metastasis, and two cases presented with malignant transformation. The metastasis rate and the rate of malignant transformation were 3.4% and 1.4% respectively. The two factors of surgery method and burst out of bone-envelope appearance were related with the recurrence. Moreover, Logistic regression revealed that the surgery method significantly affected the recurrence. And Campanacci's grade system and Jaffe's grade system were not related to each other. CONCLUSIONS: Surgery method is the main factor affected the recurrence of GCT, and Campanacci's grade system or Jaffe's grade system has no prognostic value.

Adolescent↗
PubMed2006

Case-control association study of Disrupted-in-Schizophrenia-1 (DISC1) gene and schizophrenia in the Chinese population.

Disrupted-in-Schizophrenia-1 (DISC1) has first been identified as a candidate gene for schizophrenia through study of a Scottish family with a balanced (1; 11) (q42.1; q14.3) translocation. Lots of linkage and association studies supported DISC1 as a risk factor for schizophrenia. In this study, we genotyped three SNPs in DISC1 using a set of Han Chinese samples of 560 schizophrenics and 576 controls. No positive association was detected in the whole samples but analysis of allele frequencies in female samples showed weak association between SNP rs2295959 and the disease (chi(2)=6.188, P=0.0135, OR=0.728, 95% CI=0.567-0.935). Our results provide further evidence for sex difference for the effect of the gene on the aetiology of schizophrenia. Our findings also would encourage further studies, particularly family-based association studies with larger samples, to analyze the association between DISC1 and schizophrenia.

Adult↗
PubMed2006

Results of L-[1-13C]phenylalanine breath test with air isotope ratio mass spectrometry can reflect the activity of phenylalanine hydroxylase in cirrhotic rat liver.

The L-[1-13C]phenylalanine breath test (PheBT) could potentially advance the evaluation of hepatocyte function and liver functional reserve. However, because the factors influencing PheBT results have not been clarified, the clinical application of the test has been limited. This study investigated the relationship between the parameters of PheBT, performed with air isotope ratio mass spectrometry, and the activity of phenylalanine hydroxylase (PAH), the phenylalanine metabolism rate-limiting enzyme, in rat liver, and proposes valid parameters for the assessment of liver function. Chronic injury to the liver was induced by the administration of CCl4 to male Sprague-Dawley rats for either 8 or 12 weeks. Livers from rats in the two cirrhotic groups were discolored, enlarged and roughly textured, with cells filled with fat granules of various sizes, pseudolobuli formations, and regenerated tubercles. Of the 12 parameters tested, only the unit liver weight (LW) breath test parameters, including the maximum abundance of 13C in breath (13Cmax/LW), 13C abundance in breaths 2 and 7 min after administration of L-[1-(13)C]phenylalanine (13C-phe) (13C2/LW and 13C7/LW), cumulative 13C excretion 10 and 30 min after 13C-phe administration (AUC10/LW and AUC30/LW), and the 13C excretion rate constant (PheBT-k/LW) were significantly affected in the chronic liver injury groups. There was no significant difference in the total PAH activity in liver among the three groups, but there was significant difference in unit LW PAH activity. Total PAH activity in the liver was significantly correlated with 13Cmax, 13C2, 13C7, AUC10, AUC30 and PheBT-k, while the unit LW PAH activity was significantly correlated with 13Cmax/LW, 13C2/LW, 13C7/LW, AUC10/LW, AUC30/LW and PheBT-k/LW. PheBT-k/LW was also correlated with biochemical indices that are used to assess liver function. The present findings indicate that the PheBT results based on air isotope ratio mass spectrometry can quantitatively reflect the change in total PAH activity in the livers of chronically injured rats. PheBT-k and PheBT-k/LW are the most sensitive among the test parameters, and can be used to assess liver functional reserve and hepatocyte damage at the molecular level.

Acute Disease↗
PubMed2006

Decreased hephaestin activity in the intestine of copper-deficient mice causes systemic iron deficiency.

Copper and iron metabolism intersect in mammals. Copper deficiency simultaneously leads to decreased iron levels in some tissues and iron deficiency anemia, whereas it results in iron overload in other tissues such as the intestine and liver. The copper requirement of the multicopper ferroxidases hephaestin and ceruloplasmin likely explains this link between copper and iron homeostasis in mammals. We investigated the effect of in vivo and in vitro copper deficiency on hephaestin (Heph) expression and activity. C57BL/6J mice were separated into 2 groups on the day of parturition. One group was fed a copper-deficient diet and another was fed a control diet for 6 wk. Copper-deficient mice had significantly lower hephaestin and ceruloplasmin (approximately 50% of controls) ferroxidase activity. Liver hepcidin expression was significantly downregulated by copper deficiency (approximately 60% of controls), and enterocyte mRNA and protein levels of ferroportin1 were increased to 2.5 and 10 times, respectively, relative to controls, by copper deficiency, indicating a systemic iron deficiency in the copper-deficient mice. Interestingly, hephaestin protein levels were significantly decreased to approximately 40% of control, suggesting that decreased enterocyte copper content leads to decreased hephaestin synthesis and/or stability. We also examined the effect of copper deficiency on hephaestin in vitro in the HT29 cell line and found dramatically decreased hephaestin synthesis and activity. Both in vivo and in vitro studies indicate that copper is required for the proper processing and/or stability of hephaestin.

Anemia, Iron-Deficiency↗
PubMed2006

[Self-induction of rabbit marrow stromal stem cells into chondrocytes by transfection with reconstructed PGL3-transforming growth factor beta1 gene in vitro].

OBJECTIVE: To explore an experimental method of transfecting the marrow stromal stem cells (MSCs) with the reconstructed PGL3-transforming growth factor-beta1 (TGF-beta1) gene and to evaluate the feasibility of self-induction of MSCs to the chondrocytes in vitro so as to provide a scientific and experimental basis for a further "gene enhanced tissue engineering" research. METHODS: The rabbit MSCs was transfected with the reconstructed PGL3-TGF-beta1, gene by the Liposomes Method, the growth of the cells were observed, and the growth curve was drawn. The living activity of the transfected cells in the experimental group was evaluated by MTT, and the result was significantly different when compared with that in the control group. By the immunohistochemistry method (SABC), the antigens of TGF-beta1 and collagen II were examined at 2 and 7 days of the cell culture after transfection with PGL3-TGF-beta1 gene. The pictures of the immunohistochemistry slice were analyzed with the analysis instrument, and the statistical analysis was performed with the software of the SPSS 11.0, compared with the control group and the blank group. RESULTS: Transfection of the cultured rabbit MSCs in vitro with the reconstructed PGL3-TGF-beta1 gene by the Liposomes Method achieved a success, with a detection of the Luceraferase activity. The result was significantly different from that in the control group (P < 0.01). Tested by MTT, the living activity of the transfected cells was proved to be significantly decreased (P < 0.01 vs. the control group). By the immunohistochemistry method (SABC) to study TGF beta1, positive particles were detected in the experimental group, but there were no positive particles in the control and the blank groups. There was a significant difference between the two groups of the experiment and the control group based on the analysis of the t-test (P < 0.01). By the immunohistochemistry method (SABC) to study collagen II, there were more positive particles in the transfected cells in the experimental group than in the control and the blank groups, and there was a significant difference between the experimental group and the two other groups based on the t-test (P < 0.01). CONCLUSION: Transfection of the rabbit MSCs with the reconstructed PGL3-TGF-beta1 gene by the Liposomes Method is successful. There may be some damage to the cells when transfection is performed. The transfected BMS cells with PGL3-TGF-beta1 gene can express and excrete TGF-beta1 when cultured in vitro. The transfected MSCs that secret TGF-beta1 can be self-induced into the chondrocytes after being infected for 7 days when cultured in vitro.

Animals↗
PubMed2006

[In vitro screening of 32 traditional Chinese herbal extracts against U2OS human osteosarcoma cells].

OBJECTIVE: To test 32 traditional Chinese medicinal herbs with effects against osteosarcoma in vitro. METHODS: U(2)OS human osteosarcoma cell line was treated with the extracts of the Chinese herbs at various concentrations. The changes in cell proliferation in response to the treatment were examined by MTT assay, and the effects of these extracts against human osteosarcoma growth were compared. Morphological observation, flow cytometry and Annexin V were employed to detect the cell apoptosis after the treatments. RESULTS: According to the results of MTT assay, several of the 32 Chinese herbs, especially Venenum Bufonis and oxgall powder, were identified to produce growth inhibition against U(2)OS cells. Further study of the aqueous extracts of Venenum Bufonis and oxgall powder demonstrated their effects in inducing U(2)OS cell apoptosis, and Venenum Bufonis showed the strongest effect. In spite of the obvious growth inhibitory effect of oxgall powder, its extract induced cell apoptosis only at high concentrations. CONCLUSION: Several of the traditional Chinese herbs, especially Venenum Bufonis and oxgall powder, may inhibit the growth of U(2)OS cell line, and the results of this study pave the way for further identification of the effective components in the herbs that inhibit osteosarcoma growth both in vivo and in vitro.

Antineoplastic Agents, Phytogenic↗
PubMed2005

Potential autoregulation of transcription factor PU.1 by an upstream regulatory element.

Regulation of the hematopoietic transcription factor PU.1 (Spi-1) plays a critical role in the development of white cells, and abnormal expression of PU.1 can lead to leukemia. We previously reported that the PU.1 promoter cannot induce expression of a reporter gene in vivo, and cell-type-specific expression of PU.1 in stable lines was conferred by a 3.4-kb DNA fragment including a DNase I hypersensitive site located 14 kb upstream of the transcription start site. Here we demonstrate that this kb -14 site confers lineage-specific reporter gene expression in vivo. This kb -14 upstream regulatory element contains two 300-bp regions which are highly conserved in five mammalian species. In Friend virus-induced erythroleukemia, the spleen focus-forming virus integrates into the PU.1 locus between these two conserved regions. DNA binding experiments demonstrated that PU.1 itself and Elf-1 bind to a highly conserved site within the proximal homologous region in vivo. A mutation of this site abolishing binding of PU.1 and Elf-1 led to a marked decrease in the ability of this upstream element to direct activity of reporter gene in myelomonocytic cell lines. These data suggest that a potential positive autoregulatory loop mediated through an upstream regulatory element is essential for proper PU.1 gene expression.

Animals↗
PubMed2005

[An experimental study of the effect of structure sealing of infrared CO2 sensor on its accuracy].

OBJECTIVE: To study the effect of structure sealing of infrared CO2 sensor on its accuracy. METHOD: Two experiments were designed. The IR CO2 sensor based on infrared principle and no comparing lighting path with only one beam of light were calibrated in one experiment, and in the other experiment the sensors were placed in an environment simulating the practical condition. The temperature, pressure and standard gas were kept same in the two experiments while CO2 concentrations in the dead volume were varied. RESULT: Readings from the sensors varied with the variation of the CO2 concentration in the dead volume of the sensors. CONCLUSION: The structure sealing of the IR CO2 sensor has great influence on its accuracy. A sealed dead volume in the IR CO2 sensor can decrease or eliminate the effect.

Atmospheric Pressure↗
PubMed2004

Controlled drug release from hydrogel nanoparticle networks.

Monodisperse nanoparticles of poly-N-isopropylacrylamide-co-allylamine (PNIPAM-co-allylamine) and PNIPAM-co-acrylic acid (PNIPAM-co-AA) were synthesized. The close-packed PNIPAM-co-allylamine and PNIPAM-co-AA nanoparticles were converted to three-dimensional gel networks by covalently crosslinking neighboring particles at room temperature and neutral pH using glutaric dialdehyde and adipic acid dihydrazide, respectively. Controlled release studies were conducted using dextran markers of various molecular weights as model macromolecular drugs. Release was quantified under various physical conditions, including a range of temperatures and dextran molecular weights. Dextran, entrapped in cavities in the nanoparticle network, was released with a rate regulated by their molecular weights and cavity size. No release from a conventional bulk PNIPAM gel, with high crosslinking density, was observed. The rate of release from the PNIPAM-co-allylamine network was temperature-dependent, being much faster at room temperature than that at human body temperature. In contrast, release of low molecular weight dextrans from the PNIPAM-co-AA network showed a temperature-independent release profile. These nanoparticle networks have several advantages over conventional bulk gels for controlling the release of high molecular weight biomolecules.

Acrylic Resins↗
PubMed2004

[Miniature quadrupole mass spectrometer array and its applications in manned spaceflight].

This paper explained the working method of the quadrupole mass spectrometer array and its features of volume, weight, power, sensitivity to many kinds of gases as well as flexibility when used together with a miniature gas chromatograph (GC) and a thermal-conductivity detector (TCD). Three types of structure formed in its development are also described. Finally, the applications of the quadrupole mass spectrometer array in the field of manned spaceflight were summarized.

Environmental Monitoring↗
PubMed2003

Molecular basis for a dominant inactivation of RUNX1/AML1 by the leukemogenic inversion 16 chimera.

The Runt domain transcription factor, PEBP2/CBF, is a heterodimer composed of 2 subunits. The DNA-binding alpha subunit, or RUNX protein, interacts with a partner PEBP2beta/CBFbeta through the evolutionarily conserved Runt domain. Each of the genes encoding RUNX1 and PEBP2beta/CBFbeta is frequently involved in acute myeloid leukemia. The chimeric protein, CBFbeta(PEBP2beta)/SMMHC, is generated as a result of inversion of chromosome 16 in such a way to retain the heterodimerization domain of PEBP2beta at the amino-terminal side fused to the C-terminal coiled-coil region of smooth muscle myosin heavy chain (SMMHC). Here we show that, in the chimeric protein, the second heterodimerization domain is created by the fusion junction, enabling the chimeric protein to interact with RUNX1 at far greater affinity than PEBP2beta and inactivate the RUNX1/AML1 function. To explain why and how heterozygous CBFB/MYH11 can inactivate homozygous RUNX1 near to completion, we propose a new model for this chimeric protein that consists of a Y-shaped dimer with unpaired N-terminal halves followed by a coiled-coil for the C-terminal region.

Animals↗
PubMed2003

[Eukaryotic expression of human LIGHT-Fc chimeric molecule and its anti-tumor activity].

AIM: Construct eukaryotic expression plasmid of hLIGHT-Fc gene and express hLIGHT-Fc fusion protein with high biological activity. METHODS: Utilizing PCR to clone the human LIGHT cDNA from a normal human activated T cells cDNA library phAD. CAD, then using SOE (splicing by overlap extension) technique to fuse CD137 signal peptide gene into LIGHT extramembrane domain encoding sequence, inserting this recombinated LIGHT cDNA with human IgGI Fc cDNA into the eukaryotic expression plasmid pcDNA3, expressed it transiently in 293T cells, and purified by recombinated protein A affinity chromatography column, at last we checked its Mr, purity and anti-tumor activity. RESULTS: LIGHT-Fc gene's ORF is right and coincident with we expected, then its expression was confirmed by ELISA and SDS-PAGE, and we proved that the purified LIGHT-Fc protein could inhibit the growth of some cultured tumor cell lines by MTT. CONCLUSION: we got a purified recombinated protein of LIGHT-Fc with anti-tumor activity and the anticipated Mr, thus lay a foundation for further works on LIGHT such as its role in immune homeostasis,the mechanism of its receptors' signal transduction, et al.

Antineoplastic Agents↗
PubMed2002

Serine phosphorylation of RUNX2 with novel potential functions as negative regulatory mechanisms.

The RUNX family represents a small group of heterodimeric transcription factors that master-regulate osteogenesis and hematopoiesis in mammals. Their genetic defects cause human diseases such as cleidocranial dysplasia (CCD) and acute myelogenous leukemia. However, the mechanism(s) regulating their functions are still poorly understood. Here, we report a novel observation that suggests that the osteogenesis-associated homologue RUNX2 is negatively regulated by the phosphorylation of two conserved serines (S104 and S451) in two distinct functional aspects. The phosphorylation of S104 could abolish the heterodimerization of RUNX2 with the partner subunit, PEBP2beta, which enhances the metabolic stability of RUNX2. On the other hand, the phosphorylation of S451 resides within the C-terminal transcription inhibition domain of RUNX2 and hence is implicated in its functional mobilization. One CCD mutation, S104R of RUNX2, appears to mimic the phosphorylation-dependent inhibition of heterodimerization, thereby rendering RUNX2 metabolically unstable.

Amino Acid Sequence↗