19 research outputs found
Generation and Bioenergetic Profiles of Cybrids with East Asian mtDNA Haplogroups
Human mitochondrial DNA (mtDNA) variants and haplogroups may contribute to susceptibility to various diseases and pathological conditions, but the underlying mechanisms are not well understood. To address this issue, we established a cytoplasmic hybrid (cybrid) system to investigate the role of mtDNA haplogroups in human disease; specifically, we examined the effects of East Asian mtDNA genetic backgrounds on oxidative phosphorylation (OxPhos). We found that mtDNA single nucleotide polymorphisms such as m.489T>C, m.10398A>G, m.10400C>T, m.C16223T, and m.T16362C affected mitochondrial function at the level of mtDNA, mtRNA, or the OxPhos complex. Macrohaplogroup M exhibited higher respiratory activity than haplogroup N owing to its higher mtDNA content, mtRNA transcript levels, and complex III abundance. Additionally, haplogroup M had higher reactive oxygen species levels and NAD+/NADH ratios than haplogroup N, suggesting difference in mitonuclear interactions. Notably, subhaplogroups G2, B4, and F1 appeared to contribute significantly to the differences between haplogroups M and N. Thus, our cybrid-based system can provide insight into the mechanistic basis for the role of mtDNA haplogroups in human diseases and the effect of mtDNA variants on mitochondrial OxPhos function. In addition, studies of mitonuclear interaction using this system can reveal predisposition to certain diseases conferred by variations in mtDNA
Robust estimation of bacterial cell count from optical density
Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data
Study of reference intervals for free triiodothyronine, free thyroxine, and thyroid-stimulating hormone in an elderly Chinese Han population.
The clinical manifestations of thyroid diseases in elderly patients are often atypical. This study aimed to establish reference intervals for thyroid function in the elderly in order to help diagnose thyroid diseases in this population. A total of 5345 healthy individuals were examined and divided into three groups according to their age: 4297 individuals aged < 65 years (19-64), 719 individuals aged between 65 and 79 years, and 329 individuals aged between 80 and 100 years. Levels of free triiodothyronine (FT3), free thyroxine (FT4), thyroid-stimulating hormone (TSH), thyroid peroxidase antibody, and thyroglobulin antibody were measured in these subjects by using a fully automated analyzer. The following free triiodothyronine, free thyroxine, and thyroid-stimulating hormone reference intervals were obtained from each age group: For individuals aged < 65 years (19-64 years), FT3, FT4, and TSH were 3.40-6.44, 10.26-19.25 pmol/L and 0.50-4.81 μIU/mL, respectively. For individuals aged between 65 and 79 years, FT3, FT4 and TSH ranged between 3.01-5.91, 10.04-19.76 pmol/L, and 0.54-5.51 μIU/mL, respectively. For individuals aged between 80 and 100 years, FT3, FT4, and TSH varied between 2.82-5.57, 9.79-21.22 pmol/L, 0.31-6.28 μIU/mL respectively. FT3 concentration was lower and the concentrations of FT4 and TSH were higher in individuals aged ≥ 65 years than in those aged <65 years (P<0.0001; P = 0.0039; P<0.0001, respectively). In conclusion, establishment of a reference interval would allow clinicians to diagnose diseases more accurately and easily
Correction: Study of reference intervals for free triiodothyronine, free thyroxine, and thyroid-stimulating hormone in an elderly Chinese Han population.
[This corrects the article DOI: 10.1371/journal.pone.0239579.]
Immune Regulation and Antitumor Effect of TIM-1
T cells play an important role in antitumor immunity, and the T cell immunoglobulin domain and the mucin domain protein-1 (TIM-1) on its surface, as a costimulatory molecule, has a strong regulatory effect on T cells. TIM-1 can regulate and enhance type 1 immune response of tumor association. Therefore, TIM-1 costimulatory pathways may be a promising therapeutic target in future tumor immunotherapy. This review describes the immune regulation and antitumor effect of TIM-1
Estimation of the Value of Forest Ecosystem Services in Pudacuo National Park, China
Forest ecosystems play an important role in maintaining the stability of the biosphere and improving the ecological environment. The valuation of forest ecosystem services provides data to support the implementation of forest ecosystem conservation and the development of ecological-compensation standards. We used multiple sources of data, such as remote-sensing and ground data, and we employed the methods of substitute market, shadow project, and contingent valuation. We valued the forest ecosystem services of Pudacuo National Park in Shangri-La, China, which consisted of six functions: soil conservation, forest nutrient retention, water conservation, carbon fixation and oxygen released, forest health care, and atmospheric environmental purification. The results showed that: the value of forest ecological services in Pudacuo National Park was 4.49 × 109 yuan·a−1, with higher values of carbon fixation and oxygen released, water conservation, and forest health care, in the following order: carbon fixation and oxygen released (3.85 × 109 yuan·a−1), water conservation (3.40 × 108 yuan·a−1), forest health care (1.44 × 108 yuan·a−1), soil conservation (1.15 × 108 yuan·a−1), forest nutrient retention (3.29 × 107 yuan·a−1), and atmosphere environmental purification (1.17 × 107 yuan·a−1). In addition, the value of services per stand and unit area is discussed, and the results of the study will inform the government’s ecological-compensation criteria in high-quality environmental areas
Estimation of the Value of Forest Ecosystem Services in Pudacuo National Park, China
Forest ecosystems play an important role in maintaining the stability of the biosphere and improving the ecological environment. The valuation of forest ecosystem services provides data to support the implementation of forest ecosystem conservation and the development of ecological-compensation standards. We used multiple sources of data, such as remote-sensing and ground data, and we employed the methods of substitute market, shadow project, and contingent valuation. We valued the forest ecosystem services of Pudacuo National Park in Shangri-La, China, which consisted of six functions: soil conservation, forest nutrient retention, water conservation, carbon fixation and oxygen released, forest health care, and atmospheric environmental purification. The results showed that: the value of forest ecological services in Pudacuo National Park was 4.49 × 109 yuan·a−1, with higher values of carbon fixation and oxygen released, water conservation, and forest health care, in the following order: carbon fixation and oxygen released (3.85 × 109 yuan·a−1), water conservation (3.40 × 108 yuan·a−1), forest health care (1.44 × 108 yuan·a−1), soil conservation (1.15 × 108 yuan·a−1), forest nutrient retention (3.29 × 107 yuan·a−1), and atmosphere environmental purification (1.17 × 107 yuan·a−1). In addition, the value of services per stand and unit area is discussed, and the results of the study will inform the government’s ecological-compensation criteria in high-quality environmental areas
PD-L1 Expression Promotes Epithelial to Mesenchymal Transition in Human Esophageal Cancer
Background/Aims: PD-L1 (Programmed cell death 1 ligand 1, PD-L1), an essential immune checkpoint molecule in the tumor microenvironment, is an important target for cancer immunotherapy. We have previously reported that its expression in human gastric and esophageal cancer tissues is significantly associated with cancer progression and patients’ postoperative prognoses. Its expression in cancer cells is well known to inhibit the T cell-mediated anti-tumor response, and this mechanism of action has been targeted for cancer immunotherapy. As of now, the autonomous effect of PD-L1 on cancer cells is not well understood, thus our present study aimed to examine the role of PD-L1 intervention in cellular biological functions, especially epithelial to mesenchymal transition (EMT), of the human esophageal cancer cell line, Eca-109 cells. Methods: Immunohistochemistry assay was used to investigate the correlation between expression of PD-L1 and EMT markers in human esophageal cancer tissues. Intervention of PD-L1 by using RNAi and over-expression methods were used to study the role of PD-L1 in regulation of biological behaviors and EMT in Eca-109 cells. Results: Our clinical and pathological data demonstrated that tumor samples in the EMT positive subgroup had higher PD-L1 expression than those in the EMT negative subgroup. By manipulating PD-L1 expression in Eca-109 cells either through ablation or overexpression of wild type and the cytoplasmic domain-truncated mutant, we demonstrated that PD-L1 expression significantly promoted the cell viability, migration and EMT phenotype. Furthermore, our study also indicated that PD-1 fusion protein mediated stimulation of PD-L1 and the cytoplasmic domain of PD-L1 played a critical role in promoting EMT phenotype of Eca-109 cells, thereby suggesting that PD-1 receptor usually by triggering the reverse signaling can effect PD-L1 mediated regulation of esophageal cancer cell response. Conclusion: Our present study reveals a tumor cell-autonomous role of PD-L1 signaling in promoting EMT in human esophageal cancer
Higher Numbers of T-Bet+ Tumor-Infiltrating Lymphocytes Associate with Better Survival in Human Epithelial Ovarian Cancer
Background/Aims: T-bet, a member of the T-box family of transcription factors, is a key marker of type I immune response within the tumor microenvironment, and has been previously reported by us to serve as an important prognostic indicator for human gastric cancer patients and a potential biomarker for immunotherapy. In the present study, we aimed to assess the clinical significance and prognostic value of T-bet+ tumor-infiltrating lymphocytes in human epithelial ovarian cancer. Methods: The immunohistochemistry was used to analyze the infiltration density of T-bet+ lymphoid cells in human epithelial ovarian cancer tissues, and the flow cytometry analysis was used to further analyze the presence of T-bet+ tumor-infiltrating lymphocytes subgroups in cancer tissues. Results: Our immunohistochemistry analysis showed increased number of T-bet+ lymphoid cells in the human epithelial ovarian cancer tissues, and the flow cytometry analysis further demonstrated the presence of T-bet+ tumor-infiltrating lymphocytes subgroups including CD4+ , CD8+ T cells and NK cells. In addition, we also observed a significant association of T-bet+ tumor-infiltrating lymphocytes density in the tumor nest of cancer with not only serum CA125 levels but also with distant metastasis. However no association was observed with other characteristics like patients' age, pathological type, FIGO stage, tumor site and tumor size. Furthermore, the survival analysis showed that higher density of T-bet+ tumor-infiltrating lymphocytes both in tumor nest and tumor stroma of cancer tissues was significantly associated with better patient survival. In addition, the density of T-bet+ tumor-infiltrating lymphocytes in tumor nest appeared to be an independent risk factor for predicting patients’ postoperative prognoses. Conclusions: Our data indicated that the key transcription factor T-bet might play an important role in the type I immune cells mediated antitumor response, and the density of T-bet+ lymphocytes in human epithelial ovarian cancer tissues could serve as a prognostic predictor for ovarian cancer patients
Knockdown of PD-L1 in Human Gastric Cancer Cells Inhibits Tumor Progression and Improves the Cytotoxic Sensitivity to CIK Therapy
Background/Abstract: PD-L1 has been an important target of cancer immunotherapy. We have showed that in human gastric cancer tissues, over-expression of PD-L1 was significantly associated with cancer progression and patients’ postoperative prognoses. However, as of now, how PD-L1 regulates the biological function of gastric cancer cells still remains elusive. Methods: We constructed the stable PD-L1 knockdown expression gastric cancer cell lines by using RNAi method, and further investigated the changes of biological functions including cell viability, migration, invasion, cell cycle, apoptosis, tumorigenicity in vivo, and the cytotoxic sensitivity to CIK therapy, in contrast to the control cells. Results: In the current study, we demonstrated that the knockdown of PD-L1 expression in human gastric cancer cells could significantly suppress the cell proliferation, migration, invasion, apoptosis, cell cycle, tumorigenicity in vivo and the cytotoxic sensitivity to CIK therapy. Conclusion: Our results indicate that PD-L1 contributes towards transformation and progression of human gastric cancer cells, and its intervention could prove to be an important therapeutic strategy against gastric cancer