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Yi Lin

Publications and source records attributed to Yi Lin.

At least 19 recordsLinked to original sources
PubMed2025

Genetic risk factors modulate the association between physical activity and colorectal cancer.

BACKGROUND: Physical activity (PA) is an established protective factor for colorectal cancer (CRC), but it is unclear if genetic variants modify this effect. To investigate this possibility, we conducted a genome-wide gene-PA interaction analysis. METHODS: Using logistic regression and two-step and joint tests, we analyzed interactions between common genetic variants across the genome and PA in relation to CRC risk. Self-reported PA levels were categorized as active (&#x2265; 8.75 MET-h/wk) vs. inactive (< 8.75 MET-h/wk) and as study- and sex-specific quartiles of activity. RESULTS: PA had an overall protective effect on CRC (OR [active vs. inactive] = 0.85; 95%CI = 0.81-0.90). The two-step GxE method identified an interaction between rs4779584, an intergenic variant near the GREM1 and SCG5 genes, and PA for CRC risk (p-interaction = 2.6&#xd7;10- 8). Stratification by genotype at this locus showed a significant reduction in CRC risk by 20% in active vs. inactive participants with the CC genotype (OR = 0.80; 95%CI = 0.75-0.85), but no significant PA-CRC association among CT or TT carriers. When PA was modeled as quartiles, the 1-d.f. GxE test identified that rs56906466, an intergenic variant near the KCNG1 gene, modified the association between PA and CRC (p-interaction = 3.5&#xd7;10- 8). Stratification at this locus showed that increase in PA (highest vs. lowest quartile) was associated with a lower CRC risk solely among TT carriers (OR = 0.77; 95%CI = 0.72-0.82). CONCLUSIONS: In summary, we identified two genetic variants that modified the association between PA and CRC risk. One of them, related to GREM1 and SCG5, suggests that the bone morphogenetic protein (BMP)-related, inflammatory, and/or insulin signaling pathways may be associated with the protective influence of PA on colorectal carcinogenesis.

GWAS↗
PubMed2007

[Premature delivery induced by LPS in syngenetically impregnated BALB/c and NOD/SCID mice].

AIM: To extend understanding of the mechanism of lipopolysaccharide (LPS)-induced preterm delivery in syngenetically impregnated BALB/c and NOD/SCID (nonobese diabetic/severe combined immunodeficiency) mice. METHODS: Strategies of LPS stimulation were pursued with or without previous Toll-like receptor 4 (TLR4) blocking. The incidence of LPS-induced preterm delivery and fetal death were compared between the BALB/c and NOD/SCID groups. Guided by the time when all expected preterm deliveries have occurred in the first experiment (i.e., day 16 of gestation), the LPS-stimulated mice, with or without previous TLR4 blocking, were killed at the beginning of preterm labor and pooled placentas were collected in each mouse in the second experiment. The expression of cell surface TLR4, CD80, and intracellular TNF-alpha in placenta CD45(+) cell population was determined by flow cytometry(FCM). RESULTS: It displayed that preterm delivery could be induced by LPS in BALB/c mice, while the NOD/SCID mice seemed to be resistant to LPS induction. Upon LPS stimulation, TLR4 expression was not changed either in BALB/c or in NOD/SCID mice, but the CD45(+) CD80(+) cell percentage was elevated in both groups. However, the CD45(+) TNF-alpha(+) cell percentage was increased merely in BALB/c mice after stimulation, while no such trend was observed in NOD/SCID mice. In BALB/c mice, the effect of LPS on CD80 and TNF-alpha expression could be abrogated by previous TLR4 blocking, which subsequently prevented LPS-induced preterm delivery. CONCLUSION: Although LPS do not alter TLR4 expression, it interacts with this receptor, triggers the mobilization of CD45(+) CD80(+) cells, results in elevated production of inflammatory cytokines, and finally results in preterm delivery. The diversity of sensitivity to LPS induction observed in BALB/c and NOD/SCID mice implies that the lack of functional T and NK cells in the NOD/SCID may be the reason why the NOD/SCID appeared to be resistant to LPS-induced premature labor.

Animals↗
PubMed2006

Characterization of the highly variable cry gene regions of Bacillus thuringiensis strain ly4a3 by PCR-SSCP profiling and sequencing.

Characterization of cry gene contents can help to predict the insecticidal activities of Bacillus thuringiensis isolates and in the searching of new cry genes. PCR-Single-strand conformation polymorphism (SSCP) profiling and sequencing of the highly variable cry gene regions were used to characterize cry gene content of B. thuringiensis strain ly4a3. The highly variable regions with about 1100 bp in sizes were amplified using a degenerate primer pair for cry genes, OL2(d) and OL5(r). A library of the PCR product was constructed, and all white colonies were subjected to PCR using another degenerate primer pair for cry genes, OL3(d) and OL5(r), with products about 250 bp in sizes. Two different profiles were observed based on SSCP profiling for the PCR products. The cry genes in the two corresponding colonies were sequenced and their deduced amino acids showed high identities to Cry1Ab (84.5% approximately 98.4%) and Cry1I (88.78% approximately 98.4%), respectively. This method allows the quick characterization of cry gene content of B. thuringiensis isolates and the detection of new cry genes.

Bacillus thuringiensis↗
PubMed2006

Unique aggregation of anthrax (Bacillus anthracis) spores by sugar-coated single-walled carbon nanotubes.

There has been significant interest in the binding of anthrax spores by molecular species, but with only limited success. Proteins and more recently peptides were used. However, despite the known presence of carbohydrates on the spore surface, carbohydrate-carbohydrate interactions have hardly been explored likely because of the lack of required specific platform for synthetic carbohydrates. We report the successful use of single-walled carbon nanotubes as a truly unique scaffold for displaying multivalent monosaccharide ligands that bind effectively to anthrax spores with divalent cation mediation to cause significant spore aggregation. The work should have far-reaching implications in development of countermeasure technologies.

Animals↗
PubMed2006

Efficient quenching of photoluminescence from functionalized single-walled carbon nanotubes by nitroaromatic molecules.

The photoluminescence from functionalized single-walled carbon nanotubes was found to be highly sensitive to the presence of nitroaromatic compounds such as nitrobenzene, 4-nitrotoluene, and 2,4-dinitrotoluene. The strong luminescence quenching in solution was at the upper limit of diffusion-control and also showed significant static quenching contributions. Mechanistic implication of the results and potential applications are discussed.

Dinitrobenzenes↗
PubMed2006

Preterm delivery induced by LPS in syngeneically impregnated BALB/c and NOD/SCID mice.

Strategies of lipopolysaccharide (LPS) stimulation with or without previous toll-like receptor 4 (TLR4) blocking were pursued to investigate the mechanism of LPS-induced preterm delivery in syngeneically impregnated BALB/c and non-obese diabetic (NOD)/LtSz-scid/scid (NOD/SCID [severe combined immunodeficiency] for short) mice. The LPS-stimulated mice were killed at the beginning of preterm labor and pooled placentas were collected in each mouse. Cell surface expression of TLR4, CD80, and intracellular TNF-alpha in placenta CD45(+) cell population was determined by flow cytometry. It displayed that preterm delivery could be induced by LPS in BALB/c, while the NOD/SCID seemed to be resistant to LPS induction. TLR4 expression was not changed in either BALB/c or NOD/SCID mice upon LPS-stimulation, but the CD45(+)CD80(+) cell percentage was elevated in both groups. The CD45(+)TNF-alpha(+) cell percentage was increased merely in BALB/c after the stimulation, while no such trend was observed in NOD/SCID mice. In BALB/c, the effect of LPS on CD80 and TNF-alpha expression could be abrogated by previous TLR4 blocking, subsequently prevent LPS-induced preterm delivery. In another design, NK cell blocking was performed at earlier stage of gestation by injections of anti-asialo GM1 antiserum (ASGM1). It appeared that LPS-induced preterm delivery could be partially prevented by this blocking in BALB/c mice. Such data, together with the diversity of sensitivity to LPS induction observed in BALB/c and NOD/SCID mice, imply that LPS interacts with TLR4, triggers the mobilization of CD45(+)CD80(+) cells, results in elevated production of inflammatory cytokines, and finally results in preterm delivery. In addition, NK cells may be involved in the signaling cascade, and the lack of functional NK cells in the NOD/SCID may be why these mice appeared to be less sensitive to LPS-induced premature labor.

Animals↗
PubMed2006

Quantum-sized carbon dots for bright and colorful photoluminescence.

We report that nanoscale carbon particles (carbon dots) upon simple surface passivation are strongly photoluminescent in both solution and the solid state. The luminescence emission of the carbon dots is stable against photobleaching, and there is no blinking effect. These strongly emissive carbon dots may find applications similar to or beyond those of their widely pursued silicon counterparts.

Carbon↗
PubMed2006

TLR3-involved modulation of pregnancy tolerance in double-stranded RNA-stimulated NOD/SCID mice.

This study aims to extend understanding of the relationship between TLR3-involved cell signaling and dsRNA-induced embryo resorption. Upon stimulation of dsRNA, the resorption rate of embryos was boosted dramatically in syngeneic mating BALB/c mice, but not significantly influenced in syngeneic mating NOD/SCID mice. Accordingly, there was an enhanced cell surface expression of TLR3 on placental CD45(+) cells derived from BALB/c mice, concomitant with both increased percentages of CD45(+)CD80(+) cells and CD8alpha(+)CD80(+) cells in flow cytometric analysis. In addition, both increased IL-2 and decreased IL-10 expression could be observed in CD45(+) cell group in the intracellular detection by flow cytometry. In contrast, no such trends were observed in NOD/SCID model, and its resorption rate of embryos was kept at a low level throughout pregnancy. Neutralizing Abs against TLR3 could abrogate the embryo rejection induced by dsRNA in BALB/c mice, and simultaneously could reduce the CD80(+) percentage in the CD45(+) cell group. These results indicate that the interaction between dsRNA and TLR3 may be involved in the mobilization of CD45(+)CD80(+) and CD8alpha(+)CD80(+) cells, followed by the up-regulation of IL-2 and down-regulation of IL-10 expression at the feto-maternal interface, and finally resulting in embryo rejection. The relatively low responsiveness of NOD/SCID mice may be one of the reasons why these mice appeared to be resistant to dsRNA-induced embryo resorption.

Aging↗
PubMed2006

Luminescence polarization spectroscopy study of functionalized carbon nanotubes in a polymeric matrix.

Single-walled carbon nanotubes (SWNTs) were well-functionalized for a study of their defect-derived luminescence properties. The soluble nanotube sample was homogeneously dispersed in poly(vinyl alcohol) (PVA) films via solution-phase mixing and then wet-casting. The PVA films embedded with the functionalized SWNTs were strongly luminescent according to spectroscopic and confocal microscopic results. The luminescence from the films was highly polarized, with the observed anisotropy value approaching the limit for collinear absorption and emission dipole moments. The films were mechanically stretched to align the embedded nanotubes, and results from luminescence measurements of the stretched films suggested that the excitation was strongly in favor of the direction along the nanotube axis. Mechanistic implications of the polarization spectroscopy results for the luminescent functionalized nanotubes in the polymeric matrix with and without the mechanic alignment are discussed.

Journal Article↗
PubMed2006

Potential role of toll-like receptor 3 in a murine model of polyinosinic-polycytidylic acid-induced embryo resorption.

OBJECTIVE: To investigate the potential role that toll-like receptor 3 (TLR3) may play in a murine model of polyinosinic-polycytidylic acid (polyIC)-induced embryo resorption. DESIGN: An animal model-based study on induced embryo resorption. SETTING: University animal laboratory. ANIMAL(S): Pathogen-free animals housed under barrier conditions and monitored for health status. Pregnant BALB/c mouse mated by C57BL/6 male was used as a model of allogeneic gestation. INTERVENTION(S): The administration of polyIC was performed to establish a murine model of induced embryo resorption, with or without TLR3 blocking by multiple injection of mAb against this receptor. MAIN OUTCOME MEASURE(S): Flow cytometric analysis was performed to detect the percentage of CD45(+)DX5+ and DX5(+)CD69+ cell subsets, with the DX5 antigen used as a common natural killer (NK) cell marker, and CD69 as a marker for activated NK cells, respectively. RESULT(S): In the allogeneic mating model, BALB/cxC57BL/6, both the CD45(+)DX5+ and DX5(+)CD69+ cell percentages were significantly elevated upon polyIC stimulation at the absence of anti-TLR3 administration but were kept unchanged if the female mice were pretreated with anti-TLR3 monoclonal antibody. Accordingly, the resorption rate of embryos was boosted by polyIC administration, but this effect could be abrogated by pretreatment of anti-TLR3 mAb. CONCLUSION(S): The engagement of polyIC with TLR3 may be critical to the activation of NK cells infiltrated at the feto-maternal interface, subsequently resulting in an increase in embryo resorption.

Animals↗
PubMed2006

Carbon nanotubes for immunomagnetic separation of Escherichia coli O157: H7.

Bovine serum albumin-functionalized multiple-walled carbon nanotubes with encapsulated ferromagnetic elements were conjugated with pathogen-specific antibody, and the conjugate was evaluated for immunomagnetic separation of Escherichia coli O157:H7 in pure and mixed (with Salmonella Typhimurium) cultures.

Coated Materials, Biocompatible↗
PubMed2006

[Standardization of syndrome differentiation based on stages for breast cancer: a significant and updating topic on mastology of traditional Chinese medicine].

The incidence of breast cancer increased rapidly in recent years. Breast cancer has become the most frequent malignant tumor of female especially in the developed regions. Traditional Chinese medicine (TCM) is effective in treating breast cancer, but its theories appear hysteretic, restricting the progress in clinical practice, teaching and research of TCM in the treatment of breast cancer. This article described the significance and urgency to work out the standardization of syndrome differentiation based on stages for breast cancer and put it into practice. It also analyzed the foundations, ideas and approaches of the research of standardization of syndrome differentiation based on stages for breast cancer in light of the changes of spectrum of diseases, the weaknesses of modern medicine in treating breast cancer, and the existed problems in the update clinical practice.

Antineoplastic Agents, Phytogenic↗
PubMed2006

[Change of mitochondria during apoptosis of HL-60 cells induced by camptothecine].

AIM: To study the changes of mitochondrial mass and membrane potential (deltapsi(m)) during apoptosis of human promyelocytic leukemia cells (HL-60) induced by camptothecine(CPT). METHODS: HL-60 cells were stimulated with 4x10(-6) mol/L CPT. Apoptosis and necrosis of HL-60 cells were detected by annexin V-FITC/PI staining. Mitochondrial mass and membrane potential (deltapsi(m)) were measured by NAO and DiOC(6)(3) stanings, respectively. RESULTS: After 12 hour treatment with 4x10(-6) mol/L CPT, the early apoptotic rate of HL-60 cells was significantly increased compared with the control group (12.75+/-4.61)% vs (2.88+/-2.49)%,(P<0.01), and the necrotic rate was significantly elevated too, (3.48+/-1.67)% and (0.71+/-1.10)%, (P<0.01). The result of PI staining showed that the apoptotic rate of HL-60 cells at late phase (12 h) in CPT group was (3.52+/-1.07)%, whereas that in control group was (0.46+/-1.06)%. At the same time, we observed that the cells in G(2)/M phase were arrested. The percentage of cells in G(2)/M phase in CPT group and the control was (13.45+/-1.91)% and (22.46+/-2.19)% (P<0.01) respectively. The percentage of cells with low mitochondrial mass in CPT and control groups was (25.74+/-2.09)% and (4.53+/-1.26)%, respectively (P<0.01). Mitochondrial membrane potential in CPT group and control group was (17.71+/-5.23)% and (1.64+/-2.00)%, respectively. CONCLUSION: During CPT-induced apoptosis of HL-60 cells, mitochondrial mass and membrane potential drop significantly, but its depolarization heightens.

Annexin A5↗
PubMed2006

[Comparison on growth, physiology and medicinal components of Dendrobium huoshanense hybrid and its parents].

OBJECTIVE: To compare the hybrid between species of Dendrobium huoshanense and its parents on growing, physiologic indexes and content of medicinal components, and provide theoretical basis for species quality improvement. METHOD: The chlorophyll content, the photosynthesis rate, the polysaccharides content and the alkaloids content were measured by anhydrous ethanol method, Cl-310 photosynthesis determination system, colorimetry of concentrated sulphuric acid-phenol and acid dyes colorimetry respectively. RESULT: The growth of hybrid was close to D. moniliforme, and apparently higher than D. huoshanense. The chlorophyll content and the photosynthesis rate of one-year-hybrid were markedly higher than its parents. The content of polysaccharides and alkaloids in two-year-stem and three-year-stem of hybrid were close to that of D. huoshanense. CONCLUSION: The hybrid integrates superiority of parents on growth and accumulation of medicinal components opens vast vistas for development and utilization.

Alkaloids↗
PubMed2005

Lymphocyte phenotyping and NK cell activity analysis in pregnant NOD/SCID mice.

The purpose of this study was to outline the fertility features of non-obese diabetic (NOD)/LtSz-scid/scid (NOD/SCID [severe combined immunodeficiency] for short) mice, and to evaluate the effects of NK cell subsets on the pregnancy outcomes of the syngeneic NOD/SCID x NOD/SCID mating combination. Firstly, lymphocyte phenotyping was performed with flow cytometry to confirm the multiple immunodeficits in NOD/SCID mice. Fertility features were assessed in NOD/SCID x NOD/SCID mice and compared with non-immunodeficiency control BALB/c x BALB/c mice. Although the presence of NK cell deficit is apparent in NOD/SCID mice, a certain level of remnant NK activity could be observed in these mice. The remnant NK cell activity was stimulated with polyinosinic-polycytidylic acid (polyIC), or inhibited with anti-asialo GM1 (ASGM1) anti-serum, respectively. The effects of these factors on pregnancy outcomes were evaluated after administration. Roughly normal fertility could be observed in NOD/SCID x NOD/SCID mice. However, a slightly larger sized litter was observed in polyIC-treated NOD/SCID x NOD/SCID mice compared with control NOD/SCID mice. In contrast, embryo resorption was boosted after ASGM1 injection, and correlated subsequently with a smaller litter size. It indicates that the remnant NK cell activity in NOD/SCID mice may be beneficial to feto-maternal tolerance during pregnancy.

Animals↗
PubMed2005

Following the fate of murine epidermal stem cells in a syngeneic dermal equivalent in vivo.

BACKGROUND: Stem cells in healthy epidermis have the capacity to produce structures, such as interfollicular epidermis, hair follicle, and sebaceous glands. Embryonic stem (ES) cells can be induced to differentiate into epidermal stem cells in vitro. These ESCs (epidermal or epidermoid stem cells derived from ES cells) have the potential to be an ideal replacement of those stem cells destroyed in severe injury, such as in deep and extensive burn. The aim of this study was to follow the fate of murine ESCs which were seeded in a syngeneic dermal equivalent and implanted into syngeneic recipient mice subcutaneously. METHODS: ES cells were induced in vitro to differentiate into ESCs. Stained with a fluorescent dye Hoechst 33342, these ESCs were seeded into a fibroblast-collagen-gelatin sponge complex, functioning as a dermal equivalent model, and then implanted subcutaneously into 129/J mice, which were syngeneic to these stem cells. RESULTS: These ESCs were clearly visible in the implant by fluorescent microscopy 3 weeks or longer after implantation. These cells remained viable, differentiating into hair follicle-like structures, glandular structures, and gave rise to additional structures resembling native dermis. A number of markers were expressed in the differentiated structures, including CD29 (integrin beta1 subunit) and cytokeratin 18 (CK18). No apparent rejection or severe side effects were observed at least during the 10 weeks following implantation. CONCLUSIONS: Now that ESCs can survive in vivo in this dermal equivalent model and differentiate into hair follicle-like structures as well as glandular structures, it is feasible to use these cells as seed cells in studies to fabricate dermal equivalents that have the potential to develop dermal appendages.

Animals↗
PubMed2005

Visible luminescence of carbon nanotubes and dependence on functionalization.

Strong luminescence emissions over a broad wavelength region were detected from well-dispersed carbon nanotubes in most functionalized samples, even with excitation wavelengths into the near-IR. Apparently, the better dispersion and functionalization of the nanotubes resulted in more intense luminescence emissions. These emissions may logically be attributed to the trapping of excitation energy by defect sites in the nanotube structure, which are passivated upon the appropriate functionalization of the nanotubes. Better functionalization improves not only the nanotube dispersion (thus diminishing the quenching due to intertube interactions) but also the surface passivation to make the energy trapping sites more emissive, leading to stronger luminescence emissions. Because of such high sensitivity, the visible luminescence emissions may prove valuable in the evaluation of dispersion in functionalized carbon nanotube samples and related nanocomposite materials.

Letter↗