Biomedical subjects

Juan Feng

Publications and source records attributed to Juan Feng.

At least 19 recordsLinked to original sources

PubMed2026

Predicting diagnostic gene biomarkers associated with immune infiltration in patients with diabetes.

Diabetes is a global public health problem with various complications, which can lead to disability and mortality. This study identified potential diagnostic markers for diabetes and explored the immunometabolic mechanisms in the pathological process. The gene expression of 17 diabetes cases and 16 normal controls were obtained from the Gene Expression Omnibus (GEO) database. The "limma" package was employed for screening differentially expressed genes (DEGs). Gene functions and enriched pathways of DEGs were analyzed via Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Candidate key genes were screened using the least absolute shrinkage and selection operator (LASSO) regression model and support vector machine recursive feature elimination (SVM-RFE) analysis. The diagnostic effectiveness of identified markers was further verified via the receiver operating characteristic (ROC) curve. The compositional patterns of immune cell infiltration and signaling pathway enrichment associated with key genes were explored via single sample Gene Set Enrichment Analysis (ssGSEA) and GSEA analysis, respectively. Possible miRNAs interacting with key genes were predicted via miRcode database. B2M, FTL, SH3BGRL3, and SOD2 were recognized as diagnostic markers for diabetes based on LASSO regression and the support vector machine recursive feature elimination (SVM-RFE) feature selection algorithm. Analysis of immune cell infiltration demonstrated that the four key genes were related to B cells, neutrophils, macrophages, and CD8+ T cells. The diagnostic value of B2M, FTL, and SOD2 for diabetes was higher than that of SH3BGRL3 according to the ROC curve. Validation experiments indicated that the mRNA expression of B2M and FTL was increased in liver tissues of diabetic mice. B2M and FTL can act as diagnostic markers for diabetes and contribute to new understandings of the disease's molecular mechanisms.

Humans↗

PubMed2026

Multiomic insights into fungal polylactic acid degradation: Metabolic adaptation and hydrolytic mechanisms of Sporobolomyces pararoseus.

Polylactic acid (PLA), a biodegradable polyester from renewable resources, is a sustainable alternative to petrochemical plastics. However, its environmental degradation is inefficient naturally, requiring specific microbial activities. While bacterial PLA-degrading mechanisms are well documented, fungal degrading systems-particularly their molecular mechanisms-are underexplored.We isolated Sporobolomyces pararoseus ZRQ01 from the gut microbiota of PLA-fed mealworms. This fungal strain noticeably degraded PLA in PLA-containing medium supplemented with 2% glucose. Biodegradation assays revealed 22.8% loss of the PLA film weight after 35 days of incubation, and scanning electron microscopy confirmed extensive surface erosion and pore formation. Integrated transcriptomic and proteomic analyses, together with the reference genome of S. pararoseus ZRQ01, revealed that S. pararoseus ZRQ01 upregulates hydrolytic enzymes at both transcript and protein levels to cleave PLA into lactic acid. After lactic acid is transferred into S. pararoseus ZRQ01 cells by monocarboxylate transporters with increased abundance, it is assimilated by pathways of pyruvate metabolism and the TCA cycle with increased protein abundance. Intriguingly, upregulation of genes in autophagy-related and MAPK signaling pathways underscores an adaptive stress response potentially supporting cellular homeostasis and degradation-related gene expression. Our results highlight S. pararoseus ZRQ01's metabolic potential for bioremediation and offer insights into fungal bioplastic degradation pathways.

Polyesters↗

PubMed2006

Expression of CCR7 and its ligands CCL19/CCL21 in muscles of polymyositis.

Polymyositis is an autoimmune disorder in which autoaggressive CD8(+) T cells are important in the pathogenesis. However, the mechanisms underlying sustained recruitment of these cells in the muscle tissue are still unknown. CCR7 and its ligands CCL19 and CCL21 are a chemokine system related to mononuclear cell migration and antigen presentation, and are suggested to play a key role in several autoimmune disorders. We investigated the expression of CCR7, CCL19 and CCL21 in frozen muscles of polymyositis. In immunohistochemistry, CCR7 was expressed mainly on mononuclear cells that infiltrated in the endomysium of polymyositis. 34.8+/-9.4% of endomysial mononuclear cells expressed CCR7. By double immunostaining, about 60% of endomysial CD8(+) T cells that surrounded the nonnecrotic muscle fibers coexpressed CCR7. Because most endomysial CD8(+) T cells expressed CD45RO, these were regarded as CD45RO(+)CCR7(+)CD8(+) T cells. On the other hand, CCL19 was expressed mainly on muscle fibers in proximity to CCR7(+) mononuclear cells, on the endothelium of the vessels and some mononuclear cells. CCL21 immunoreactivities were found on small numbers of mononuclear cells. In some cases, CCL21 immunoreactivities were also found on muscle fibers and the endothelium of vessels. In RT-PCR analysis, transcripts of CCR7 and CCL21 were detected in all the polymyositis muscles examined and that of CCL19 was detected in five out of seven polymyositis muscles. The CCL19,CCL21/CCR7 chemokine system is expressed in inflamed muscles of polymyositis and may be involved in the pathomechanism of polymyositis.

Adolescent↗

PubMed2006

Molecular characterization of a HMW glutenin subunit allele providing evidence for silencing of x-type gene on Glu-B1.

Understanding the molecular structure of high-molecular-weight glutenin subunit (HMW-GS) may provide useful evidence for the study on the improvement of quality of cultivated wheat and the evolution of Glu-1 alleles. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) shows that the subunits encoded by Glu-B1 were null, named 1Bxm, in a Triticum turgidum var. dicoccoides line PI94640. Primers based on the conserved regions in wheat HMW-GS gene promoter and coding sequences were used to amplify the genomic DNA of line PI94640. The PCR products were sequenced, and the total nucleotide sequence of 3,442 bp including upstream sequence of 1,070 bp was obtained. Compared with the reported gene sequences of Glu-1Bx alleles, the promoter region of the Glu-1Bxm showed close resemblance to 1Bx7. The Glu-1Bxm coding region differs from the other Glu-1Bx alleles for a deduced mature protein with only 212 residues, and a stop codon (TAA) at 637 bp downstream from the start codon was present, which was probably responsible for the silencing of x-type subunit genes at the Glu-B1 locus. Phylogenetic tree based on the nucleotide sequence alignment of HMW glutenin subunit genes showed that 1Bxm was the most ancient type of Glu-B1 alleles, suggesting that the evolution rates are different among Glu-1Bx genes. Further study on the contribution of the unique silenced Glu-B1 alleles to quality improvement was also discussed.

Alleles↗

PubMed2006

[Sequence variation of chloroplast gene infA-rpl36 region occurred in some Triticeae species].

Based on the sequenced wheat chloroplast genome (cpDNA), a pair of primers in infA-rp136 region was designed and used to amplify DNA from 12 diploid or polyploid Triticeae species. The 12 PCR products were cloned and sequenced. The resulting sequences ranged from 584 to 601 bp. DNA sequence analysis revealed that variation was higher in their intergenic regions than in their coding regions. Among these 12 species, the DNA sequence of coding region of infA gene showed homology as high as 97 percent, indicating that the infA gene is highly conserved among species. However, substantial deletions and insertions were found in 5 out of 12 deduced amino acid sequences, confirming that infA is one of the most evolutionally active cpDNA genes. Whereas the low variation was observed in rp136 gene, implying that the different genes has different evolutionary speed. The constructed phylogenetic trees demonstrate that the polyploidy species Thinopyrum intermedium might have different origin of cytoplasm, and their cytoplasm origins are as complex as their nuclear genome origins.

Amino Acid Sequence↗

PubMed2006

[Development of Dasypyrum genome specific marker by using wheat microsatellites].

One hundred and two SSR primer pairs, distributed in chromosome 1A to 7A, 1B to 7B, 1D to 7D of Triticum aestivum, were investigated on Dasypyrum breviaristatum, D.villosum, wheat-Dasypyrum amphiploids and its derivatives, with the control of common wheat Chinese Spring and elite wheat cultivars. A specific polymorphic DNA fragment of about 400 bp (415 bp-long by sequenced, named Xgwm301/415) amplified by primer pair Xgwm301 was obtained in all lines containing Dasypyrum chromosomes, but there were not the case in the tested common wheat. Furthermore, PCR analysis was performed on a set of T. aestivum-Dasypyrum addition, the result showed that all the seven pairs of villosum chromosomes contain Xgwm301/415. Therefore, Xgwm301/415 is a genome-specific polymorphic DNA segment for genera of Dasypyrum, and it could be used as a molecular marker for detection of chromosomes of Dasypyrum in wheat.

Base Sequence↗

PubMed2006

[Cloning and analysis of gene encoding wheat translation initiation factor, eIF5A].

Eukaryotic translation initiation factor 5A (eIF5A) is involved in cell proliferation, senescence, development and environmental response. In this paper, DNA and cDNA of Chinese Spring was amplified by PCR with special primers, two special fragments of 1 679 bp and 1 910 bp were obtained with DNA as template and one special fragment of 636 bp was yielded with cDNA as template. Which were named eIF5a1 (GenBank number: DQ167202), eIF5a2 (Genbank number: DQ167201) and eIF5a3, respectively. The complete sequence (768 bp) of eIF5a3 (Genbank number: DQ167203) was obtained using GeneRacer kit. Nucleotide sequence analysis shows that eIF5a1 and eIF5a2 share identical transcriptions of 636bp which have only 6 nucleotides difference. Putative amino acid sequences analysis revealed that there was only one or two amino acid difference in eIF5a1, eIF5a2 and eIF5a3. Phylogenic analysis indicated that the eIF5A of wheat were relation to corn, rice, tomato and potato closely. In additional, eIF5a2 is located on chromosome 2B using Langdon D-genomic disomic substitution lines and the expression of eIF5A was also investigated by Semi-quantitative PCR.

Amino Acid Sequence↗

PubMed2005

Resist-free patterning of surface architectures in polymer-based microanalytical devices.

The ability to form patterns of chemically reactive surface functionalities in microanalytical devices using a simple photopatterning approach without the need for photoresist-based methods is described. Direct UV exposure of the surfaces of poly(methyl methacrylate), PMMA, and poly(carbonate), PC, microfluidic devices through optical masks leads to the production of patterns of near monolayer quantities of surface carboxylic acid groups as determined by surface coverage, X-ray photoelectron spectroscopy, and fluorescence microscopy experiments. Formation of the reactive carboxylic acid groups without significant physical (topographical) damage to the polymer device substrates is achieved by use of low UV fluence and exposure times. Modification of the patterned, surface carboxylic acid groups with metals, thermally responsive polymers, and antibodies results in microfluidic devices possessing metallic interconnects and detection electrodes and the ability to capture intact biological cells and proteins from solution.

Methylmethacrylates↗

PubMed2005

Chemokine profile in the cerebrospinal fluid and serum of Vogt-Koyanagi-Harada disease.

We analyzed the concentrations of four chemokines in the cerebrospinal fluid (CSF) and sera in Vogt-Koyanagi-Harada disease (VKH), an autoimmune uveomeningitis syndrome against melanocyte-associated proteins, with ELISA. CSF-CXCL10/IP-10 and CSF-CCL17/TARC were significantly elevated in VKH than in controls. In the majority of VKH cases and controls, CSF-CXCL10 was higher than serum-CXCL10, and CSF-CCL17 was lower than serum-CCL17. CCL11/Eotaxin was not different between groups. CSF-CCL2/MCP-1 was significantly lower in VKH than in control. The changes in VKH were essentially similar to those in multiple sclerosis, a known Th1-dominant condition.

Adolescent↗

PubMed2005

Molecular cytogenetic characterization and disease resistance observation of wheat-Dasypyrum breviaristatum partial amphiploid and its derivatives.

A wheat-Dasypyrum breviaristatum partial amphiploid and its derivatives were analyzed by molecular cytological observation and tested for disease resistance in order to evaluate the potential use of the D. breviaristatum for wheat improvement. A fertility-improved partial amphiploid, TDH-2, was produced from the selfing population of Triticum aestivum cv. Chinese spring (CS)-D. breviaristatum amphiploid. Based on the results obtained from genomic in situ hybridization (GISH) and seed protein electrophoresis, we found the presence of fourteen D. breviaristatum chromosomes and the absence of D genome in TDH-2, indicating that the genomic composition of TDH-2 was AABBV(b)V(b). GISH analysis on BC(1)F(4) progenies of TDH-2xwheat demonstrated that alien D. breviaristatum chromosomes or segments were frequently transmitted. A survey of diseases resistance revealed that powdery mildew resistance from D. breviaristatum was totally expressed, however, the expression of stripe rust resistance from D. breviaristatum was dependent on the wheat background. The comparison of polymerase chain reaction (PCR), which was carried out using molecular marker SCAR(1400) linked to Pm21 D. villosum-derived powdery mildew resistance gene, suggested that D. breviaristatum possessed new resistance gene(s) different from that in D. villosum. The present study showed that the partial amphiploid TDH-2 and its derivatives could serve as novel sources for transfer of disease resistance genes to wheat.

Chromosomes, Plant↗

PubMed2004

CSF-chemokines in HTLV-I-associated myelopathy: CXCL10 up-regulation and therapeutic effect of interferon-alpha.

We measured four chemokines in the cerebrospinal fluid (CSF) in human T-lymphotropic virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) with ELISA. CXCL10/IP-10, a T cell type 1 (Th1)-associated chemokine, was significantly elevated in HAM/TSP compared with controls, and the values were even significantly higher in HAM/TSP than in multiple sclerosis (MS) in which CXCL10/IP-10 up-regulation was previously reported. Among Th2-associated chemokines, CCL17/TARC and CCL11/Eotaxin in HAM/TSP were not different from those in controls. As shown in MS, CCL2/MCP-1 was significantly lower in HAM/TSP than in control. Following interferon (IFN)-alpha therapy in HAM/TSP, CCL2/MCP-1 became significantly higher than that before therapy, which may reflect a Th2 induction, while CXCL10/IP-10 remained elevated.

Adult↗

PubMed2004

Th1/Th2 balance and HTLV-I proviral load in HAM/TSP patients treated with interferon-alpha.

We studied the immunological and virological effects of interferon-alpha (IFN-alpha) therapy in nine patients with HTLV-I-associated myelopathy (HAM/TSP). After therapy, the percentages of CCR5+ cells in CD4+ cells significantly decreased in the cerebrospinal fluid as well as blood. The therapy also significantly lowered the intracellular IFN-gamma+/interleukin-4+ T-cell ratio in blood. Those helper T-cell type 1 (Th1)-related responses tended to be higher and reduce more evidently following therapy in three patients who clinically improved. Also, all the three patients had one or more HTLV-I copies in five blood mononuclear cells. These results suggest that IFN-alpha suppresses Th1 responses in HAM/TSP and that the patients with higher Th1 immunity and proviral loads may be responders of the therapy. Larger-scale studies are needed to confirm the findings.

Aged↗

PubMed2004

Triplet Excitation Transfer between Carotenoids in the LH2 Complex from Photosynthetic Bacterium Rhodopseudomonas palustris.

We have studied, by means of sub-microsecond time-resolved absorption spectroscopy, the triplet-excited state dynamics of carotenoids (Cars) in the intermediate-light adapted LH2 complex (ML-LH2) from Rhodopseudomonas palustris containing Cars with different numbers of conjugated double bonds. Following pulsed photo-excitation at 590 nm at room temperature, rapid spectral equilibration was observed either as a red shift of the isosbestic wavelength on a time scale of 0.6-1.0 mus, or as a fast decay in the shorter-wavelength side of the T(n)<--T(1) absorption of Cars with a time constant of 0.5-0.8 mus. Two major spectral components assignable to Cars with 11 and 12 conjugated double bonds were identified. The equilibration was not observed in the ML-LH2 at 77 K, or in the LH2 complex from Rhodobacter sphaeroides G1C containing a single type of Car. The unique spectral equilibration was ascribed to temperature-dependent triplet excitation transfer among different Car compositions. The results suggest that Cars of 11 and 12 conjugated bonds, both in close proximity of BChls, may coexist in an alpha,beta-subunit of the ML-LH2 complex.

Journal Article↗

PubMed2004

Ibudilast, a nonselective phosphodiesterase inhibitor, regulates Th1/Th2 balance and NKT cell subset in multiple sclerosis.

We investigated the immunoregulatory effects of ibudilast, a nonselective phosphodiesterase inhibitor, at a clinically applicable dose (60 mg/day p.o. for four weeks) in multiple sclerosis (MS) patients. Sensitive real-time PCR for quantifying cytokine mRNA in the blood CD4+ cells revealed that the ibudilast monotherapy significantly reduced tumour necrosis factor-alpha and interferon (IFN)-gamma mRNA and the IFN-gamma/interleukin-4 mRNA ratio, suggesting a shift in the cytokine profile from Th1 toward Th2 dominancy. In a flow cytometric analysis, natural killer T cells, which have been reported to relate to Th2 responses in MS and its animal model (experimental autoimmune encephalomyelitis), increased significantly after the therapy. None of the significant immunological changes were seen in healthy subjects or untreated MS patients. Ibudilast may be a promising therapy for MS and its clinical effects warrant further study.

Adult↗

PubMed2003

Nanosecond time-resolved studies of long-lived photoinduced charge separation in the dyad fluorescein-anthraquinone-methyl ester adsorbed on TiO2 colloids.

A dyad composed of fluorescein and 2-methyl-anthraquinone (FL-AQ) was synthesized and its photophysical properties were examined by absorption, fluorescence spectroscopy, and fluorescence lifetime. The charge-separated state formed by photoinduced intramolecular electron transfer was detected by nanosecond transient absorption spectroscopy for the first time. When FL is excited in solution, the photoinduced electron transfer from FL to AQ proceeds efficiently. The rate constant and the efficiency of intramolecular electron transfer are 3.95 x 10(9) s(-1) and 95%, respectively. Its charge-separated state lifetime is too short to detect by transient absorption spectroscopy. Adding nanometer colloidal TiO(2) to an FL-AQ ethanol solution prolongs the lifetime of the charge-separated state, so its transient absorption signal is recorded significantly. The lifetimes of FL(+). at 480 nm and AQ(-). at 560 nm in the FL-AQ/TiO(2) colloidal system are 11.1 and 8.93 mivros, respectively.

Journal Article↗

PubMed2003

Dual emission from 3MLCT and 3ILCT excited states in a new Ru(II) diimine complex.

The unique behavior of a new Ru(II) diimine complex, Ru(bpy)(2)(L)(2+) (where L is 4-methyl-4'-[p-(dimethyl- amino)-alpha-styryl]-2,2'-bipyridine, bpy is 2,2'-bipyridine), was studied in detail. Due to the strong electron donating property of the amino group, an ILCT (intraligand charge transfer) state is involved either in the absorption spectra or in the time-resolved emission spectra. Dual emission based on (3)MLCT and (3)ILCT states was observed at room temperature for the first time via a time-resolved technique in Ru(II) diimine complexes.

Journal Article↗

PubMed2003

Interferon-alpha significantly reduces cerebrospinal fluid CD4 cell subsets in HAM/TSP.

We, for the first time, analyzed T cell and natural killer (NK) cell subsets in the cerebrospinal fluid (CSF) in nine patients with human T-lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) treated with interferon-alpha (IFN-alpha). The CD4/CD8 ratio in CSF was significantly lower after the therapy, which is mainly attributable to the significant reduction in CD4+ cells, especially CD25+CD4 and CD45RO+CD4 cell subsets. Meanwhile, NK, natural T and NKT cell subsets in the CSF remained unchanged. There was no CSF lymphocyte subset significantly associated with the clinical efficacy of IFN-alpha in this small-scale study, and more patients should be analyzed to ascertain the link.

Aged↗

PubMed2002

[A preliminary study on the immune suppressive protein of stress in human tonsil].

Our previous work demonstrated that under the conditions of restraint stress and under the control of central nervous system (CNS), an immune suppressive protein of stress (ISPS) was generated in peripheral lymph tissue and released into the blood stream, acting as an immune suppressor. In the present work, a protein similar to ISPS was found in human tonsil (a peripheral lymph tissue). Human tonsil was homogenized and the extract was prepared. It was found that lymphocyte proliferation was significantly suppressed by the extract. The suppression induced by the extract was partially reversed by the monoclonal antibody against ISPS (2C4). In ELISA test, the extract was able to bind to the monoclonal antibody. By immunohistochemistry, many ISPS positive cells were found in human tonsil. The ISPS positive cells were also found in human lymph nodes. Taken together, all the results demonstrate that a protein similar to ISPS may exist in human peripheral lymphoid tissue.

Animals↗