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Peng Gao

Publications and source records attributed to Peng Gao.

At least 19 recordsLinked to original sources
PubMed2026

Isolation and characterization of two novel species Neorhizobium fuzhouense sp. nov. and Neotabrizicola paludis sp. nov.

Two novel aerobic bacterial strains, designated SGZ-38T and sgz301269T, were isolated from the root of Pennisetum sp. and paddy soil, respectively. Strain SGZ-38T grew at 10-40 ℃ (optimum 30 °C) and pH 5.0-12.0 (optimum 6.5) and tolerated up to 1.0% NaCl (w/v), whereas strain sgz301269T grew at 15-37 °C (optimum 30 °C), pH 5.0-9.5 (optimum 7.0) and 0-2% NaCl (optimum 0%). Phylogenetic trees based on the 16S rRNA gene and genomes placed both strains into distinct lineages, forming separated clades from their closest relatives. Strain SGZ-381T exhibited the highest 16S rRNA gene similarities to "Neorhizobium deserti" ACCC 61627T (97.4%), and strain sgz301269T had the highest 16S rRNA gene sequence similarity to Neotabrizicola shimadae N10T (97.6%). The respiratory quinone in both strains was ubiquinone-10. The main fatty acids of SGZ-381T were Summed feature 8, Summed feature 2 and C16:0, whereas strain sgz301269T included C10:0 3OH, C18:0 3OH and Summed feature 8. The DNA G+C content of SGZ-381T and sgz301269T was 62.1% and 65.5%, respectively. The average nucleotide identity and digital DNA-DNA hybridization values between each strain and their respective closest species were 74.6% and 20.1%, 75.3% and 17.4% respectively, below the thresholds for species delineation. Based on the comprehensive chemotaxonomic, phylogenetic, and phenotypic evidence, proposed names of the novel strains are Neorhizobium fuzhouense sp. nov. (type strain SGZ-381T=GDMCC1.4207T=JCM 36770T), Neotabrizicola paludis sp. nov. (type strain sgz301269T=MCCC 1K09178T=KCTC 8856T).

Bacterial Typing Techniques↗
PubMed2026

ProMeta: a meta-learning framework for robust disease diagnosis and prediction from plasma proteomics.

MOTIVATION: The plasma proteome offers a dynamic window of human health, capturing the real-time intersections between genetics and physiology. However, the application of deep learning to proteomics is currently hindered by a reliance on large-scale labeled datasets, rendering standard models ineffective for rare or novel diseases where patient samples are inherently scarce. RESULTS: Here, we present ProMeta, a meta-learning framework designed to enable robust disease modeling under extreme data restrictions. By integrating knowledge-guided pathway encoding with bi-level meta-optimization, ProMeta projects unstructured proteomic profiles into biologically interpretable functional tokens. This architecture allows the model to learn a global initialization containing transferable biological priors from biobank-scale data, facilitating rapid adaptation to novel tasks. Through comprehensive benchmark experiments, ProMeta consistently outperformed transfer learning and traditional machine learning baselines in both disease diagnosis and prediction tasks. In the most challenging 4-shot scenarios (utilizing only 2 cases and 2 controls), the model achieved robust generalization with an average AUROC of ∼0.69, representing a 24.6% relative improvement over the best-performing baseline methods. Mechanistic investigation revealed that ProMeta disentangles cases from controls in the latent space prior to task-specific adaptation, confirming the acquisition of universal biological rules rather than rote memorization. Furthermore, gradient-based interpretation identified disease-specific protein biomarkers and functional pathways consistent with known pathophysiology. Collectively, ProMeta overcomes the data-scarcity bottleneck in precision medicine, providing a scalable, interpretable framework for characterizing the full spectrum of human diseases, particularly for rare conditions lacking extensive clinical cohorts. AVAILABILITY AND IMPLEMENTATION: The source code of ProMeta is available at GitHub (https://github.com/lihan97/ProMeta).

Proteomics↗
PubMed2026

Description of two nitrogen-fixing bacteria, Azospirillum mesophilum sp. nov. and Azospirillum terrae sp. nov., isolated from paddy soils.

Two novel aerobic, rod-shaped, motile bacterial strains, designated as sgz302134T and sgz301742T, were isolated from paddy soil in Fujian Province. Strains sgz302134T and sgz301742T shared the highest 16S rRNA gene sequence similarities with the type strains Azospirillum isscasi C340-1T (98.2%) and Azospirillum thiophilum DSM 21654T (97.4%), respectively. The phylogenetic tree based on 16S rRNA gene sequences showed that two strains clustered with members of the genus Azospirillum. Growth of strains sgz302134T and sgz301742T was observed at 10-45 °C, pH 5.0-9.5 and 0-0.5% (w/v) NaCl and 15-37 °C, pH 6.0-9.0 and 0-1.0% (w/v) NaCl, respectively. Strains sgz302134T and sgz301742T contained Q-10 as the main quinone. The main fatty acids (>10%) of both strains were summed feature 2 (C12 : 0 aldehyde), summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) and C16 : 0. The genomic DNA G+C content of strains sgz302134T and sgz301742T was 68.4 and 68.3%, respectively. The digital DNA-DNA hybridization and average nucleotide identity values between the two strains and their related reference strains were 27.8 and 87.4% and 22.0 and 84.3%, respectively. Both strains possessed nif genes nifBDEHKN. Based on the above results, these two strains represent two novel species of the genus Azospirillum, for which the names Azospirillum mesophilum sp. nov. and Azospirillum terrae sp. nov. are proposed. The type strains are sgz302134T (=MCCC 1K09520T=KCTC 8840T) and sgz301742T (=MCCC 1K09804T=KCTC 18149T), respectively.

Soil Microbiology↗
PubMed2025

Enhancing and accelerating cell type deconvolution of large-scale spatial transcriptomics slices with dual network model.

MOTIVATION: Cell type deconvolution deciphers spatial distribution of mRNA transcripts at single cell level by integrating single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics data to infer mixture of cell types of spots in slices. Current algorithms are criticized for neglecting connection between scRNA-seq and spatial transcriptomics data, as well as time-consuming, hampering their application to large-scale datasets. RESULTS: In this study, we propose a joint learning nonnegative matrix factorization algorithm for fast cell type deconvolution (aka jMF2D), which integrates scRNA-seq and spatial transcriptomics data with network models. To bridge scRNA-seq and spatial transcriptomics data, jMF2D jointly learns cell type similarity network to enhance quality of signatures of cell types, thereby promoting accuracy and efficiency of deconvolution. Experiments demonstrate that jMF2D outperforms state-of-the-art baselines in terms of accuracy by saving about 90% running time on various datasets generated by different platforms. Furthermore, it can also facilitates the identification of spatial domains and bio-marker genes, providing an efficient and effective model for analyzing spatial transcriptomics data. AVAILABILITY AND IMPLEMENTATION: The software is coded using python, and is free available for academic https://github.com/xkmaxidian/jMF2D.

Algorithms↗
PubMed2006

Total synthesis of indole alkaloid (+/-)-subincanadine F via SmI2)-mediated ring opening and bridge-forming Mannich reaction.

The first total synthesis of (+/-)-subincanadine F, a bioactive indole alkaloid structurally featuring a 1-azabicyclo[4.3.1]decane unit, has been realized from 1-(para-methoxybenzyl)tryptamine in six steps. The bridge-containing tetracyclic framework of subincanadine F was efficiently assembled by a SmI2-mediated ring opening followed by an acid-mediated Mannich reaction. In addition, the tetracyclic ketoester 6, a key intermediate potentially useful for synthesizing structurally related indole alkaloids as well, was obtained in one step from alpha,beta-diketoester 5.

Cyclization↗
PubMed2006

Compression induced helical nanotubes in a spreading film of a bolaamphiphile at the air/water interface.

Inspired by the elegant helical structures endowed by mother nature, we designed an L-glutamic acid terminated bolaamphiphile and obtained helical nanotubes through the manipulation on the two-dimensional Langmuir films at the air/water interface. It has been found that on the subphase with a pH value lower than 3, stable monolayers with plateau regions were obtained for the bolaamphiphile. Although a flat and uniform morphology was observed for the film deposited at a surface pressure below the plateau region, helical nanotube structures were obtained when the film was compressed over the plateau region. It was suggested that the compression of the monolayer at the air/water interface caused the one end of the bolaamphiphile to leave from the water surface and form an intermediate monolayer in which one end group attached on the water surface and the other extruded in the air. Such an intermediate monolayer subsequently rolled into a helical structure due to the chiral nature of the L-glutamic acid headgroup.

Compressive Strength↗
PubMed2006

Reversal MDR in breast carcinoma cells by transfection of ribozyme designed according the secondary structure of mdr1 mRNA.

Multidrug resistance (MDR) is a major obstacle in cancer chemotherapy. The present study aims to investigate whether the ribozyme could reverse MDR in breast carcinoma cells. In this study, two GUC sites (GUC106 and GUC135) on the surface of mdr1 mRNA were selected according to the secondary structure of the 5'-region of mdrl mRNA. The ribozyme gene RZ106 and RZ135 complementary to two sides bases of the target GUC were synthesized and cloned into the plasmid pEGFP -C1 which has EGFP (Enhanced Green Fluorescence Protein) as report gene and Kan/Neo as selection gene. After transfection with the recombinant plasmid and selected by G418, the stable cell clones were produced and used for detection. The alteration of mdr1 mRNA and P-gp in the treated cells was detected by RT-PCR, flow cytometry and Rh123 retention. The reversal efficiency of the drug resistance for adriamycin was determined by MTT assay. The results showed that after transfection with RZ106 and RZ135, the amount of the mdr1 mRNA and P-gp decreased significantly and the efflux function of P-gp was inhibited accordingly. Nine-fold and 16-fold reduction of resistance for adriamycin was observed in the two groups of treated cells. These results suggested that both ribozymes can reverse the MDR phenotype by inhibiting the expression of mdr1 mRNA and P-gp, and the RZ135 showed the better cleavage efficiency. The ribozyme strategy designed according the secondary structure of the target RNA could be a useful therapy for reversal of MDR.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2006

Cell-based screening and validation of human novel genes associated with cell viability.

In the present study, a cell-based high-throughput assay is established to identify novel human genes associated with cell viability. The assay relies on the down-regulation of Renilla luciferase (pRL) activity in a 96-well format. In addition, 2-color fluorescence probes were used to distinguish living and dead cells. As the positive control, the authors used the expression vectors encoding Bax, TNFRSF1A, and TAJ, which were widely known to effectively induce programmed cell death. They screened 409 novel genes (including alternative mRNA splicing forms) cloned in their laboratory and found that 39 genes could significantly down-regulate pRL activity. A subsequent fluorescence-based assay revealed that 4 of the 39 genes (PIP5KL1, OLFM1, RNF122, FAM26B) were associated with cell viability. Further function assays validated that the 4 genes were able to induce both necrosis and apoptosis. These results therefore indicate that a rapid and effective screening system has been developed, which should shed light on some functions of novel genes.

Apoptosis↗
PubMed2006

Controlled synthesis of double- and multiwall silver nanotubes with template organogel from a bolaamphiphile.

Double- and multiwall silver nanotubes were synthesized by using the uniform low-molecular-mass organogel nanotubes self-assembled from an L-glutamic-acid-based bolaamphiphile, N,N-eicosanedioyl-di-L-glutamic acid (EDGA). The EDGA could gel a mixed water/ethanol solvent and form helical nanotubes. When the gel thus formed was mixed with AgNO3 in water/ethanol, the silver(I) cations could be coordinated with both the inner and outer surfaces of the EDGA nanotubes. The reduction of the silver cation under the photoirradiation yielded double-wall silver nanotubes, where two silver layers were separated by one EDGA layer. Elongations of the reduction time of the mixed gels and AgNO3 in the solution lead to the formation of three-, four-, and five-wall silver nanotubes. In these multiwall silver nanotubes, each wall was separated at a distance of about 2.7 nm, which was just the molecular length of the bolaamphiphile. It was suggested that the dissolved EDGA molecules and excess Ag(I) cations were further assembled onto the surface of the formed double-wall silver nanotubes and, as a consequence, the photoreduction caused the formation of the third-wall silver nanotubes. The multiwall silver nanotubes were further formed in a similar way. The factors affecting the formation of the silver wall nanotubes such as the relative amount of AgNO3 to EDGA and the synthetic conditions were discussed.

Journal Article↗
PubMed2006

Rapid detection of Staphylococcus aureus by a combination of monoclonal antibody-coated latex and capillary electrophoresis.

The rapid detection of pathogenic bacteria is extremely important in biotechnology and clinical diagnosis. CE has been utilized in the field of bacterial analysis for many years, but to some extent, simultaneous separation and identification of certain microbes from complex samples by CE coupled with UV detector is still a challenge. In this paper, we propose a new strategy for rapid separation and identification of Staphylococcus aureus (S. aureus) in bacterial mixtures by means of specific mAb-coated latex coupled with CZE. An appropriate set of conditions that selectively isolated S. aureus from the microorganisms Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae were established. S. aureus could be differentiated from the others by unique peaks in the electropherograms. The validity was also confirmed by LIF with antibodies specific to both the latex and the microbial cells. The LOD is as low as 9.0 x 10(5) colony forming unit/mL. We have also utilized this technology to identify S. aureus in a stool sample coming from a healthy volunteer spiked successfully with S. aureus. This CZE-UV technique can be applied to rapid diagnosis of enteritis caused by S. aureus or other bacterial control-related fields needing rapid identification of target pathogens from microbial mixtures. In theory, this method is suitable for the detection of any bacterium as long as corresponding bacterium-specific antibody-coated latex is available.

Antibodies, Bacterial↗
PubMed2006

Lymphatic vessel density as a prognostic indicator for patients with stage I cervical carcinoma.

Lymphatic vessel density (LVD) was recently considered important for spread of several malignant tumors. However, there are no reports describing the situation in cervical carcinoma. The purpose of this study was to investigate whether LVD could serve as a risk factor for nodal metastasis and recurrence of cervical carcinoma in 147 cases of stage I patients. Other questions were if depth of invasion, proliferation rate, and tumor size could be used as predictive markers for Chinese patients with cervical carcinoma. The lymphatics were determined by immunohistochemistry with the antibody to LYVE-1, a specific lymphatic endothelium marker, and average LVD was calculated. Double immunohistochemistry and double immunofluorescence staining for LYVE-1/CD34 were used to distinguish between lymphatic and blood vessels. The results showed that average LVD in cervical carcinoma was statistically associated with inflammatory cell infiltration of carcinoma tissues, but not associated with other pathological parameters. Average LVD of the cases with nodal metastasis or recurrence was significantly higher than the cases without metastasis and recurrence in both stage IA and stage IB cervical carcinomas. The correlation between both depth of invasion and tumor size with nodal metastasis and recurrence of cervical carcinoma was also statistically significant. Ki-67 labeling index was found to be correlated with the recurrence of disease, but not to be correlated with nodal metastasis. We concluded that for the patients with stage I cervical carcinoma, increased LVD could serve as a high-risk factor for nodal metastasis and recurrence. Depth of invasion and tumor size could also be useful indicators.

Biomarkers, Tumor↗
PubMed2006

High performance liquid chromatography-mass spectrometry for metabonomics: potential biomarkers for acute deterioration of liver function in chronic hepatitis B.

Metabonomics methods have been successfully applied to the drug discovery, toxicology, phytochemistry, and clinical fields. Here, we report a self-developed metabonomics platform which is based on high performance liquid chromatography-mass spectrometry (HPLC-MS) technique and applied to the investigation of acute deterioration of liver function in chronic hepatitis B to find the potential biomarkers. Sera from 50 healthy persons and 37 patients with acute deterioration of liver function in chronic hepatitis B were analyzed by HPLC-MS after removal of proteins. After de-noise, peak detection and peak alignment, the data of metabolites were fed to partial least squares discriminant analysis (PLS-DA) to find the potential biomarkers. According to the corresponding tandem mass results, several potential biomarkers were identified: Lysophosphatidyl Choline (LPC) C18:0, LPC C16:0, LPC C18:1, LPC C18:2, and glycochenodeoxycholic acid (GCDCA) (or its isomer glycodeoxycholic acid (GDCA)). On the basis of the relevant literature and pathway databases, the biological significance of the present study is discussed.

Adult↗
PubMed2006

[Reversion the multidrug resistance of human breast carcinoma cells by RNA interference targeting HIF-1 alpha gene].

OBJECTIVE: To reverse the multidrug resistant (MDR) phenotype of human breast carcinoma cells by small hairpin RNA (shRNA) technique targeting hypoxia-inducible factor (HIF)-1alpha gene. METHODS: Small hairpin RNA (shRNA) eukaryotic expression vector targeting HIF-1alpha gene, named pSilencer-HIF, was constructed and transfected into MCF-7/ADR human breast cancer cells by liposome technique. Tumor cell livability (TCL) and Rhodamine 123 efflux assay were used to monitor the biological changes of the transfected cells. The mRNA and protein expression of HIF-1alpha and mdr-1 were investigated by RT-PCR and Western blot. RESULTS: The successful construction of pSilencer-HIF plasmid was confirmed by DNA sequencing. HIF-1alpha mRNA and protein levels were significantly decreased in MCF-7/ADR cells after the transfection and there was a direct correlation between HIF-1alpha and mdr-1 expression. By comparing the cells transfected with control vector and the MCF-7/ADR cells transfected with pSilencer-HIF, a reduced TCL from 76% to 43%, and an increased Rhodamine 123 fluorescence intensity from 22.0% to 86.6% were observed. CONCLUSIONS: pSilencer-HIF-1alpha has been successfully constructed. The inhibition of HIF-1alpha expression through shRNA technique can significantly reverse the multidrug resistance phenotype of MCF-7/ADR cells.

Breast Neoplasms↗
PubMed2006

[Preliminary research of hepatocarcinoma stem cell markers].

OBJECTIVE: To study human hepatocarcinoma stem cell markers. METHODS: Tumor tissue samples were obtained from 8 patients with hepatic cellular cancer undergoing surgical tumor resection and the tumor cells were cultured with primary tissue culture in vitro. The cell subpopulations with each marker were isolated from the tumor cells by immunopanning using oval cell markers (CD34, c-kit, Thy-1, CK7, CK19, CK14). The cells of each phenotype were injected into nude mice to measure their ability of tumor formation and the tumor mass was weighed one month after implantation. The tumorigenic subpopulations of the cells were injected into the nude mice again in 1/4 or 1/10 of their original densities to further analyze their ability of tumor formation. RESULTS: Among all the cell subpopulations, those positive for CD34, c-kit and CK7, respectively, showed marked difference from the negative cells in their ability of proliferation and tumor formation. The CD34(-), c-kit(+) and CK7(+) subpopulations of the cells exhibited strong capacity of tumor formation even in only 1/4 or 1/10 of their original density. CONCLUSIONS: There are heterogeneous subpopulations within human hepatocarcinoma with observable difference in tumor formation ability. The strong tumor formation ability of CD34(-), c-kit(+) and CK7(+) subpopulation of the cells suggests that CD34(-), c-kit(+) and CK7(+) represent part of the surface markers of hepatocarcinoma stem cells.

Antigens, CD34↗
PubMed2006

[Antisense oligonucleotide against survivin induces apoptosis and enhances adriamycin sensitivity of SMMC-7721/ADM cells].

OBJECTIVE: To explore the effects of survivin-specific antisense oligonucleotide (ASODN) delivered via liposome on the growth and apoptosis of drug-resistant human hepatic cancer cell line SMMC-7721/ADM and the sensitivity of the cells to adriamycin (ADM). METHODS: SMMC-7721/ADM cells were divided into 6 groups and treated with liposome, ADM, sense oligonucleotide (SODN), SODN+ADM, 400 ng/ml ASODN, and 400 ng/ml ASODN+ADM group, respectively. MTT assay was used to calculate the relative survival rates of the cells, and the changes in cell apoptosis and cycle were detected with flow cytometry. RT-PCR and Western blotting were performed to detect the expressions of survivin mRNA and protein, respectively. RESULTS: The apoptotic rate of ASODN-treated cells was much higher than that of the control cells. survivin protein expression showed no significant variation between cells treated with liposome, ADM, SODN, and SODN+ADM (P>0.05), whereas compared with these 4 groups, cells treated with 400 ng/ml ASODN and 400 ng/ml ASODN+ADM had significantly lowered survivin mRNA expression (P<0.05), without significant differences between the latter two groups (P>0.05). SMMC-7721/ADM cells cultured in the presence of ASODN and adriamycin showed significant growth inhibition in comparison with ASODN group and ADM group. CONCLUSION: survivin-specific ASODN can enhance the sensitivity of SMMC-7721/ADM cells to ADM by depressing survivin expression in the cells, thus improves the effect of ADM chemotherapy for liver cancer.

Antibiotics, Antineoplastic↗
PubMed2005

[Strategy for treatment of peritrochanteric fractures in senile patients].

OBJECTIVE: To analyze the clinical manifestations, operative applications, complications and outcomes of peritrochanteric fracture of femur in patients 75-years old and over. METHODS: The clinical data of 261 patients, aged 79.5 (75-96), of peritrochanteric fracture (265 hips) were analyzed. RESULTS: The incidence of different accompanied medical diseases was 2.6/person on average. The internal fixation methods included DHS, DHS plus trochanteric steady plate or intramedullary interlocking nails, such as Gamma nail, PFN and reconstructive nails. The mean operation time was 73 minutes. 224 cases were followed-up over 6 months after operation 81% of which got excellent or good results. The complications included acute heart failure, brain infarction, cerebral thrombosis, pulmonary embolism, deep venous thrombosis of lower extremities, lung infection, and stress ulceration, bed sore, and acute respiratory failure. Thirteen cases died of cardiopulmonary insufficiency, cardiac infarction, brain thrombosis, or pulmonary embolism. CONCLUSION: Complications are frequent in aged patients. Appropriate operative methods help reduce complications and mortality rates.

Aged↗
PubMed2005

Interfacial Langmuir-Blodgett assembly of straight and parallel aligned nanoribbons.

The fabrication of one-dimensional nanomaterials is currently an important issue in nanoscience and nanotechnology. Herein, we report the construction of long, straight, and parallel aligned nanoribbons, by the in situ assembly of a novel, triangular amphiphilic molecule at an air-water interface. The 1,3,5-trimesyl-tri-L-glutamic acid hexaester, which has an aromatic core with three hydrophilic arms bearing three amide units and ending with six ester groups, was spread on a water surface, forming a stable, ultrathin film with a plateau region in its isotherm. When the film was compressed to a surface pressures, which exceeded the plateau region, nanoribbons were formed. Atomic force microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, transmission electron microscopy, electron diffraction, and circular dichroism were used to characterize the film and the nanoribbons. The nanoribbons were formed due to the in situ transformation of a two-dimensional monolayer into a three-dimensional nanoarchitecture at the air-water interface. When the compound was spread onto the water surface, it first formed a monolayer. Compressing the film led to the overlap of the second layer on the monomolecular sublayer. This second layer formed nanoribbons in which the triangular molecules stood vertically (using two corners) on the sublayer. The nanoribbons were stabilized by the ordered packing of the triangular molecules, which were held together by intermolecular hydrogen bonding. The results present a facile procedure for constructing three-dimensional, regular nanoarchitectures in a two-dimensional environment.

Magnetic Resonance Spectroscopy↗