Biomedical subjects

Yong Yang

Publications and source records attributed to Yong Yang.

At least 19 recordsLinked to original sources

PubMed2026

Ionizing radiation induces bidirectional transcriptomic reprogramming and dynamic NOS2/TREM2 regulation in triple-negative breast cancer cells.

PURPOSE: To characterize irradiation-associated transcriptomic changes in murine triple-negative breast cancer cells and examine dose- and time-response patterns of selected radiation-responsive candidates. MATERIALS AND METHODS: RNA sequencing (RNA-seq) was performed in 4T1 cells collected 24 h after 4 Gy irradiation, followed by Reactome and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment and gene set enrichment analyses. Representative RNA-seq-derived genes were examined by reverse transcription quantitative PCR (RT-qPCR), and selected immune- and inflammation-related transcripts were further assessed across additional radiation doses and post-irradiation time points. Inducible nitric oxide synthase (NOS2) and triggering receptor expressed on myeloid cells 2 (TREM2) protein abundance was assessed by Western blotting, and nitrite accumulation in culture supernatants was measured using a Griess reagent-based assay as an indirect readout of nitric oxide production. RESULTS: RNA sequencing identified 757 differentially expressed genes, including 285 upregulated and 472 downregulated genes. Irradiation was associated with enrichment of inflammatory, interferon-related, immune-system, and cell-adhesion transcriptional signatures, whereas downregulated genes were enriched in cell-cycle-, chromosome-cohesion-, DNA-damage-response-, DNA-repair-, and SUMOylation-related pathways. Selected immune- and inflammation-related transcripts showed distinct temporal patterns. Nos2 mRNA increased across the examined 0-6 Gy dose range and at later post-irradiation time points, whereas NOS2 protein showed different kinetics, with an early peak after 4 Gy irradiation and no clear further increase above 6 Gy. Nitrite accumulation increased after irradiation. Trem2 showed the largest fold increase among strongly upregulated transcripts identified by RNA-seq, but RT-qPCR detected a significant increase only at 24 h, and TREM2 protein abundance remained unchanged across the examined doses and time points. CONCLUSIONS: Ionizing radiation was associated with broad bidirectional transcriptional remodeling in 4T1 cells, involving immune-, inflammatory-, and interferon-related signatures together with reduced representation of cell-cycle- and DNA-repair-related gene sets. The discordant mRNA and protein patterns of NOS2 and TREM2 indicate that transcript-level responses do not necessarily translate into corresponding protein-level changes. These findings define irradiation-associated molecular responses requiring further functional investigation.

Triple-negative breast cancer↗

PubMed2026

Phylogenomics and evolution of the Lauraceae based on targeted capture data.

The family Lauraceae, a hyper-diverse magnoliid family comprising approximately 63 genera and over 3,000 species, plays a key ecological role in tropical and subtropical forests. Yet deep relationships among its nine tribes remain unresolved, likely due to limited sampling and complex evolutionary processes such as incomplete lineage sorting (ILS) and gene flow. To address these challenges, we generated datasets of 255 single-copy nuclear genes and chloroplast genomes using a newly designed Lauraceae-specific probe set, achieving the most comprehensive genus-level sampling (84%) to date. Phylogenomic analyses reconstructed a robust nuclear tree, which resolved the Neocinnamomeae as sister to the Caryodaphnopsideae and revealed pronounced gene tree conflict and pervasive cytonuclear discordance. To investigate the evolutionary processes underlying these patterns, comprehensive analyses were conducted. The results indicate that conflicting nuclear gene trees reflect the combined effects of ILS, gene tree estimation error, and gene flow, with ILS dominating across the core Lauraceae, whereas cytonuclear discordance is primarily driven by extensive gene flow. Diversification analyses further indicate that episodes of rapid lineage accumulation coincide with major gene flow events, suggesting a potential role of gene flow in the diversification of Lauraceae. Overall, this study provides a robust nuclear phylogenomic framework for Lauraceae and demonstrates that gene flow had profound effects on its evolutionary history, shedding light on the contribution of gene flow to the diversification of hyper-diverse tropical plant lineages.

Cytonuclear discordance↗

PubMed2026

The complete chloroplast genome of Heterostemma pingtaoi (Apocynaceae).

Heterostemma pingtaoi, a species endemic to Hainan Island, China, was discovered and formally described in the family Apocynaceae in 2010. However, genetic and evolutionary information on the genus Heterostemma remains poorly understood. Here, we report the complete chloroplast (cp) genome sequence of H. pingtaoi. The genome displays the typical quadripartite structure characteristic of dicotyledonous plant cp genomes, with a total length of 162,681 bp and a GC content of 38.25%. The cp genome encodes 131 genes, including 84 protein-coding genes, 8 rRNA genes, and 39 tRNA genes. Phylogenetic analysis based on the complete cp genome sequences confirmed that the genus Heterostemma forms a monophyletic group at the base of tribe Ceropegieae (Apocynaceae), with 100% bootstrap support. This study provides essential genomic resources for future taxonomic and evolutionary studies of Heterostemma species.

Apocynaceae↗

PubMed2026

Association of lipoprotein-associated phospholipase A2 with recurrence risk and its predictive value in large artery atherosclerotic stroke.

OBJECTIVE: To investigate the association of lipoprotein-associated phospholipase A2 (Lp-PLA2) with large artery atherosclerotic (LAA) stroke and its predictive value for recurrence. METHODS: We consecutively enrolled 412 acute LAA stroke patients. Using a cutoff of 200 ng/mL, patients were divided into high and low Lp-PLA2 groups, and into recurrence and non‑recurrence groups based on 1‑year follow‑up. Baseline characteristics, lipid profiles, National Institutes of Health Stroke Scale (NIHSS) scores, and vascular stenosis degree were compared. Binary logistic regression and Receiver Operating Characteristic (ROC) analysis were used to identify independent risk factors and evaluate predictive value. RESULTS: The high Lp-PLA2 group had significantly higher low-density lipoprotein cholesterol (LDL-C), small dense low-density lipoprotein cholesterol (sdLDL-C), prevalence of severe stenosis (≥70%), and proportion of NIHSS > 15 (all P < 0.05). The recurrence group showed elevated Lp-PLA2, higher LDL‑C and sdLDL-C, more severe neurological deficits, and more severe stenosis (all P < 0.001). Multivariable regression identified elevated Lp-PLA2 (per 10 ng/mL: OR = 1.139, 95% CI: 1.089-1.191), moderate (OR = 3.145) and severe (OR = 11.663) neurological deficits, and severe stenosis (OR = 9.390) as independent risk factors for recurrence (all P < 0.05). The Area Under the Curve (AUC) of Lp-PLA2 was 0.75 (95% CI: 0.69-0.82), with an optimal cutoff of 208.95 ng/mL. CONCLUSION: Elevated Lp-PLA2 is associated with adverse lipid profiles, more severe neurological deficits, and greater vascular stenosis in LAA stroke patients, and independently predicts 1‑year recurrence. Lp-PLA2 shows moderate predictive value, supporting its potential for risk stratification.

Humans↗

PubMed2025

Proteomic signatures and predictive modeling of cadmium-associated anxiety in middle-aged and elderly populations: an environmental exposure association study.

BACKGROUND: Emerging evidence implicates environmental contaminants such as cadmium (Cd) as modifiable risk factors for anxiety. Despite growing recognition of heavy metal toxicity in neuropsychiatric disorders, the molecular mechanisms linking environmental exposure to anxiety pathogenesis remain poorly understood. METHODS: Based on the established cohort of individuals with cognitive impairment in cadmium-contaminated areas, this cross-sectional association study enrolled 50 middle-aged and elderly hospitalized patients from these regions, adhering to the STROBE guidelines. Blood concentrations of cadmium (Cd), lead (Pb), and mercury (Hg) were analyzed in relation to anxiety severity assessed via the Hamilton Anxiety Rating Scale (HAMA). Plasma proteomic profiling was performed using data-independent acquisition (DIA) quantitative technology with an LC-MS/MS platform (timsTOF Pro, Bruker Daltonics), systematically characterizing 2,531 proteins across all samples. Machine learning techniques, specifically XGBoost and LASSO, were employed to identify biomarkers that were subsequently validated through mediation analysis and animal experiments, allowing for the screening of key protein signatures. Finally, clinical variables were integrated to construct a comprehensive model, which was then thoroughly evaluated. RESULTS: Anxious individuals exhibited significantly higher blood Cd levels than controls (β = 0.50, 95% CI: 0.07-0.93, p < 0.01), with anxiety positively correlating with depression (r = 0.62, p = 0.003) and inversely with ApoE3 genotype prevalence. Proteomics identified 120 differentially expressed proteins in anxious patients, enriched in oxidative phosphorylation and neurodegenerative pathways. CCDC126 emerged as a cadmium-associated biomarker, validated in rat models exposed to Cd. Combining CCDC126, blood Cd, Pb, and hypertension, a clinical prediction model achieved robust discrimination (AUC = 0.80, validation cohort). CONCLUSIONS: This first integrative environmental-proteomic study highlights cadmium's synergistic role in anxiety pathophysiology and psychiatric comorbidity. The predictive model offers translatable potential for early risk stratification, while CCDC126 provides mechanistic insights for targeted interventions in populations exposed to environmental pollutants.

Cadmium↗

PubMed2007

Increased expression of integrin beta1 subunit enhances p21WAF1/Cip1 transcription through the Sp1 sites and p300-mediated histone acetylation in human hepatocellular carcinoma cells.

Integrins, a class of membrane receptors, are major players in transmitting the mechanical force across the plasma membrane. We previously reported that overexpression of integrin beta1 subunit imposed a growth inhibitory effect on the hepatocellular carcinoma cell line SMMC-7721 through transcriptional activation of p21(WAF1/CIP1) gene. In this study, we further determined the molecular mechanisms underlying p21(WAF1/CIP1) expression induced by integrin beta1 overexpression. We report herein that overexpression of integrin beta1 subunit upregulates p21(WAF1/Cip1) transcription through a p53-independent pathway. The overexpressed integrin beta1 activates the p21(WAF1/Cip1) promoter through the Sp1/Sp3 sites and makes more transcription factor Sp1 recruited to the proximal p21 promoter region. In addition, it makes the acetylation value of histone proteins increased across some parts of the p21(WAF1/Cip1) gene, especially in the promoter region. The transcriptional co-activator p300, which possesses intrinsic histone acetyltransferase, was found to be involved in the integrin beta1-mediated histone acetylation and p21 transcriptional activation. Therefore, these findings presented the mechanisms by which integrin beta1 induced the elevated p21 expression in hepatic cancer cells.

Acetylation↗

PubMed2007

Evaluation of on-board kV cone beam CT (CBCT)-based dose calculation.

On-board CBCT images are used to generate patient geometric models to assist patient setup. The image data can also, potentially, be used for dose reconstruction in combination with the fluence maps from treatment plan. Here we evaluate the achievable accuracy in using a kV CBCT for dose calculation. Relative electron density as a function of HU was obtained for both planning CT (pCT) and CBCT using a Catphan-600 calibration phantom. The CBCT calibration stability was monitored weekly for 8 consecutive weeks. A clinical treatment planning system was employed for pCT- and CBCT-based dose calculations and subsequent comparisons. Phantom and patient studies were carried out. In the former study, both Catphan-600 and pelvic phantoms were employed to evaluate the dosimetric performance of the full-fan and half-fan scanning modes. To evaluate the dosimetric influence of motion artefacts commonly seen in CBCT images, the Catphan-600 phantom was scanned with and without cyclic motion using the pCT and CBCT scanners. The doses computed based on the four sets of CT images (pCT and CBCT with/without motion) were compared quantitatively. The patient studies included a lung case and three prostate cases. The lung case was employed to further assess the adverse effect of intra-scan organ motion. Unlike the phantom study, the pCT of a patient is generally acquired at the time of simulation and the anatomy may be different from that of CBCT acquired at the time of treatment delivery because of organ deformation. To tackle the problem, we introduced a set of modified CBCT images (mCBCT) for each patient, which possesses the geometric information of the CBCT but the electronic density distribution mapped from the pCT with the help of a BSpline deformable image registration software. In the patient study, the dose computed with the mCBCT was used as a surrogate of the 'ground truth'. We found that the CBCT electron density calibration curve differs moderately from that of pCT. No significant fluctuation was observed in the calibration over the period of 8 weeks. For the static phantom, the doses computed based on pCT and CBCT agreed to within 1%. A notable difference in CBCT- and pCT-based dose distributions was found for the motion phantom due to the motion artefacts which appeared in the CBCT images (the maximum discrepancy was found to be approximately 3.0% in the high dose region). The motion artefacts-induced dosimetric inaccuracy was also observed in the lung patient study. For the prostate cases, the mCBCT- and CBCT-based dose calculations yielded very close results (<2%). Coupled with the phantom data, it is concluded that the CBCT can be employed directly for dose calculation for a disease site such as the prostate, where there is little motion artefact. In the prostate case study, we also noted a large discrepancy between the original treatment plan and the CBCT (or mCBCT)-based calculation, suggesting the importance of inter-fractional organ movement and the need for adaptive therapy to compensate for the anatomical changes in the future.

Biophysical Phenomena↗

PubMed2007

Polycomb-like genes are necessary for specification of dopaminergic and serotonergic neurons in Caenorhabditis elegans.

The molecular mechanisms underlying the formation of neurons with defined neurotransmitters are not well understood. In this study, we demonstrate that the PcG-like genes in Caenorhabditis elegans, sop-2 and sor-3, regulate the formation of dopaminergic and serotonergic neurons and several other neuronal properties. sor-3 encodes a novel protein containing an MBT repeat, a domain that contains histone-binding activity and is present in PcG proteins SCM and Sfmbt in other organisms. We further show that mutations in sor-3 lead to ectopic expression of Hox genes and cause homeotic transformations. Specification of certain neuronal identities by these PcG-like genes appears to involve regulation of non-Hox gene targets. Our studies revealed that the PcG-like genes are crucial for coordinately regulating the expression of discrete aspects of neuronal identities in C. elegans.

Amino Acid Motifs↗

PubMed2007

Increase in beta1-6 GlcNAc branching caused by N-acetylglucosaminyltransferase V directs integrin beta1 stability in human hepatocellular carcinoma cell line SMMC-7721.

In this study, an enzymatic inactive mutant of GnT-V (delta cGnT-V) was constructed and transfected in SMMC 7721 cell line. Integrin beta1 in delta cGnT-V transfectants (delta c-7721) showed attenuation of the number of beta1-6 GlcNAc branching, whereas those in wtGnT-V transfectants (wt-7721) presented a beta1-6 GlcNAc-rich pattern. High integrin beta1 expression was observed in wt-7721 compared with mock cells (7721 cell transfected with the vector pcDNA3), while transfection of delta cGnT-V decreased the integrin beta1 expression, despite of no significant changes on integrin beta1 mRNA level in these cell lines. Pulse-chase experiment showed that Integrin beta1 in delta c-7721 was prone to quick degradation and its half-life was less than 3 h, on the contrary, the alleviating degradation of beta1 subunit was observed in wt-7721 where the beta1 subunit half-life was about 16 h, meanwhile, the degradation rate of beta1 subunit in mock cells was in between, about 10 h. More effective in promoting cell migration toward fibronectin and invasion through Matrigel was observed in wt-7721 while this was almost suppressed in delta c-7721. Our results suggest that the addition of beta1-6 GlcNAc branching caused more fully glycosylated mature form on integrin beta1 and inhibited beta1 protein degradation. Glycosylation caused by GnT-V directs integrin beta1 stability and more delivery to plasma membrane, subsequently promotes Fn-based cell migration and invasion.

Acetylglucosamine↗

PubMed2007

Design of a phosphinate-based fluorescent probe for superoxide detection in mouse peritoneal macrophages.

3',6'-Bis(diphenylphosphinyl)fluorescein (PF-1) was synthesized as a highly selective and sensitive fluorescent probe for imaging O(2) (.-) in living cells. The design strategy for the probe was based on the nucleophilic mechanism of O(2) (.-) to mediate deprotection of this probe to give fluorescein. Upon reaction with O(2) (.-), the probe exhibits a strong fluorescence response and high selectivity for O(2) (.-) over other reactive oxygen species and some biological compounds. The phosphinate-based probe, as a new fluorescent reagent, is cell-permeable and can detect micromolar changes of O(2) (.-) concentrations by using confocal microscopy in living cells. The unique combination of good selectivity, high sensitivity, good water solubility, and rapid reactivity establishes the potential value of the probe for facilitating investigations of the generation, metabolism, and mechanisms of superoxide-mediated cellular homeostasis and injury.

Animals↗

PubMed2007

Requirements of Src family kinase during meiotic maturation in mouse oocyte.

The Src family kinase (SFK) is important in normal cell cycle control. However, its role in meiotic maturation in mammalian has not been examined. We used confocal microscope immunofluorescence to examine the in vitro dynamics of the subcellular distribution of SFK during the mouse oocyte meiotic maturation and further evaluated the functions of SFK via biochemical analysis using a specific SFK pharmacological inhibitor, PP(2). Our results showed that nonphospho-SFK was absent in oocyte upon its release from follicle. Nonphospho-SFK appeared in cytoplasm 0.5 hr after the release of oocyte and translocated to germinal vesicle (GV) before germinal vesicle breakdown (GVBD). After GVBD, nonphospho-SFK colocated with condensed chromosomes. In occyte at metaphase I (MI) and telophase I, nonphospho-SFK accumulated in the cortex and the cleavage furrow respectively besides its existence in cytoplasm in both stages. In oocyte at metaphase II (MII), nonphospho-SFK concentrated at the aligned chromosomes. In contrast, phospho-SFK was absent in oocyte until 1 hr after its release from the follicle. Phospho-SFK accumulated in the GV, the cortex, and cytoplasm immediately prior to GVBD. After GVBD, phospho-SFK evenly distributed in oocyte. In oocyte at MII, phospho-SFK localized throughout the cytoplasm and under the egg member. When the SFK activity was inhibited, the oocyte failed to initiate GVBD, could not go into MII, and could not extrude the first polar body. Our results demonstrated that SFK is required for meiotic maturation in mouse oocyte.

Animals↗

PubMed2007

Haloarcula amylolytica sp. nov., an extremely halophilic archaeon isolated from Aibi salt lake in Xin-Jiang, China.

A starch-hydrolysing and extremely halophilic archaeon (strain BD-3(T)), isolated from Aibi salt lake in Xin-Jiang, China, was characterized phenotypically and genotypically in order to determine its taxonomic status. On the basis of its polar lipid composition, nucleotide sequences of its 16S rRNA genes, genomic DNA G+C content (62.4 mol%) and growth characteristics, the organism could be assigned to the genus Haloarcula. Phenotypic differences and low DNA-DNA hybridization values to related Haloarcula species distinguished strain BD-3(T) from recognized Haloarcula species. It is therefore concluded that strain BD-3(T) represents a novel species, for which the name Haloarcula amylolytica sp. nov. is proposed. The type strain is BD-3(T) (=CGMCC 1.5335(T)=JCM 13557(T)).

Bacterial Typing Techniques↗

PubMed2006

Assembly of three-dimensional polymeric constructs containing cells/biomolecules using carbon dioxide.

Using low-pressure carbon dioxide (CO2), we demonstrated a novel and versatile approach to assembling polymeric constructs in the presence of cells and/or biomolecules in an aqueous environment. By regulating the CO2 pressure, the assembly was completed at biologically permissive temperatures with excellent preservation of the original structures. We further demonstrated that mammalian cells can survive the CO2-assisted bioassembly process (37 degrees C, 1.38 MPa, approximately 1 h). Human mesenchymal stem cells from bone marrow (hMSCs) exhibited the same cell morphology and proliferation potential as the untreated control. Mouse embryonic stem cells (mESCs) maintained ES-specific Oct-4 gene expression and differentiation potential after CO2 treatment as well. This method highlights the ability to construct multiple biodegradable polymeric scaffolds with well-defined architecture, on which various types of cells were grown, into a predesigned three-dimensional complex. In addition, protein and DNA bioactivity can be preserved in the context of a CO2-assisted assembly. This CO2-assisted bioassembly method provides for a manufacturing platform that, thus far, has been lacking in the fields of tissue engineering, cell-based biochips, cell therapy, and drug delivery.

Carbon Dioxide↗

PubMed2006

Combination of integrin siRNA and irradiation for breast cancer therapy.

Up-regulation of integrin alpha(v)beta(3) has been shown to play a key role in tumor angiogenesis and metastasis. In this study, we evaluated the role of integrin alpha(v)beta(3) in breast cancer cell resistance to ionizing irradiation (IR) and tested the anti-tumor efficacy of combining integrin alpha(v) siRNA and IR. Colonogenic survival assay, cell proliferation, apoptosis, and cell cycle analysis were carried out to determine the treatment effect of siRNA, IR, or combination of both on MDA-MB-435 cells (integrin alpha(v)beta(3)-positive). Integrin alpha(v)beta(3)-negative MCF-7 cells exert more radiosensitivity than MDA-MB-435 cells. IR up-regulates integrin alpha(v)beta(3) expression in MDA-MB-435 cells and integrin alpha(v) siRNA can effectively reduce both alpha(v) and alpha(v)beta(3) integrin expression, leading to increased radiosensitivity. Integrin alpha(v) siRNA also promotes IR-induced apoptosis and enhances IR-induced G2/M arrest in cell cycle progression. This study, with further optimization, may provide a simple and highly efficient treatment strategy for breast cancer as well as other integrin alpha(v)beta(3)-positive cancer types.

Breast Neoplasms↗

PubMed2006

Oroxylin A induced apoptosis of human hepatocellular carcinoma cell line HepG2 was involved in its antitumor activity.

We previously reported that wogonin, a flavonoid compound, was a potent apoptosis inducer of human hepatoma SMMC-7721 cells and murine sarcoma S180 cells. In the present study, the effect of oroxylin A, one wogonin structurally related flavonoid isolated from Scutellariae radix, on human hepatocellular carcinoma cell line HepG2 was examined and molecular mechanisms were also investigated. Oroxylin A inhibited HepG2 cell proliferation in a concentration- and time-dependent manner measured by MTT-assay. Treatment with an apoptosis-inducing concentration of oroxylin A caused typical morphological changes and apoptotic blebbing in HepG2 cells. DNA fragmentation assay was used to examine later apoptosis induced by oroxylin A. FACScan analysis revealed a dramatic increase in the number of apoptotic and G(2)/M phase arrest cells after oroxylin A treatment. The pro-apoptotic activity of oroxylin A was attributed to its ability to modulate the concerted expression of Bcl-2, Bax, and pro-caspase-3 proteins. The expression of Bcl-2 protein and pro-caspase-3 protein was dramatically decreased after treatment with oroxylin A. These results demonstrated that oroxylin A could effectively induce programmed cell death and suggested that it could be a promising antitumor drug.

Antineoplastic Agents↗

PubMed2006

Theoretical study of hydrogen bonding interaction in nitroxyl (HNO) dimer: interrelationship of the two N-H...O blue-shifting hydrogen bonds.

The hydrogen bonding interactions of the HNO dimer have been investigated using ab initio molecular orbital and density functional theory (DFT) with the 6-311++G(2d,2p) basis set. The natural bond orbital (NBO) analysis and atom in molecules (AIM) theory were applied to understand the nature of the interactions. The interrelationship between one N-H...O hydrogen bond and the other N-H...O hydrogen bond has been established by performing partial optimizations. The dimer is stabilized by the N-H...O hydrogen bonding interactions, which lead to the contractions of N-H bonds as well as the characteristic blue-shifts of the stretching vibrational frequencies nu(N-H). The NBO analysis shows that both rehybridization and electron density redistribution contribute to the large blue-shifts of the N-H stretching frequencies. A quantitative correlations of the intermolecular distance H...O (r(H...O)) with the parameters: rho at bond critical points (BCPs), s-characters of N atoms in N-H bonds, electron densities in the sigma*(N-H), the blue-shift degrees of nu(N-H) are presented. The relationship between the difference of rho (|Deltarho|) for the one hydrogen bond compared with the other one and the difference of interaction energy (DeltaE) are also illustrated. It indicates that for r(H...O) ranging from 2.05 to 2.3528 A, with increasing r(H...O), there is the descending tendency for one rho(H...O) and the ascending tendency for the other rho(H...O). r(H...O) ranging from 2.3528 to 2.85 A, there are descending tendencies for the two rho(H...O) with increasing r(H...O). On the potential energy surface of the dimer, the smaller the difference between one rho(H...O) and the other rho(H...O) is, the more stable the structure is. As r(H...O) increases, the blue-shift degrees of nu(N-H) decrease. The cooperative descending tendencies in s-characters of two N atoms with increasing r(H...O) contribute to the decreases in blue-shift degrees of nu(N-H). Ranging from 2.05 to 2.55 A, the increase of the electron density in one sigma*(N-H) with elongating r(H...O) weakens the blue-shift degrees of nu(N-H), simultaneously, the decrease of the electron density in the other sigma*(N-H) with elongating r(H...O) strengthens the blue-shift degrees of nu(N-H). Ranging from 2.55 to 2.85 A, the cooperative ascending tendencies of the electron densities in two sigma*(N-H) with increasing r(H...O) contribute to the decreases in blue-shift degrees of nu(N-H).

Dimerization↗

PubMed2006

Prohibitin suppresses renal interstitial fibroblasts proliferation and phenotypic change induced by transforming growth factor-beta1.

Prohibitin (PHB), a potential tumor suppressor, has been shown to inhibit cell proliferation by repressing E2F-mediated transcription. But little is known about the role of PHB involved in tubulointerstitial fibrosis (TIF). Here, for the first time, we found PHB protein was positively expressed at normal renal tissues, strongly down-regulated in renal biopsy specimens, and negatively correlated with the expression of alpha-smooth-muscle actin (alpha-SMA) and with the degrees of tubulointerstitial lesions. Transforming growth factor-beta1 (TGF-beta1) is the most important profibrotic cytokine in the process of TIF and capable of inducing cell phenotypic change of interstitial fibroblasts characterized by the de novo expression of alpha-SMA. Confocal microscopy showed majority of PHB is located at cytoplasm as well as at nucleus in rat kidney fibroblasts cell (NRK-49F). As we found that PHB protein and mRNA expression were down-regulated in NRK-49F cells following TGF-beta1 stimulation. We used transient transfection to over-express PHB protein and found that cells with increased PHB levels had a significant reduction in the percentage entering cell cycle and abolished de novo expression of alpha-SMA following TGF-beta1 stimulation. Therefore, over-expression of PHB suppresses renal interstitial fibroblasts proliferation and cell phenotypic change induced by TGF-beta1, which indicates PHB as a potential therapeutic target to halt the progression of TIF.

Actins↗

PubMed2006

Dosimetric effects of patient rotational setup errors on prostate IMRT treatments.

The purpose of this work is to determine dose delivery errors that could result from systematic rotational setup errors (DeltaPhi) for prostate cancer patients treated with three-phase sequential boost IMRT. In order to implement this, different rotational setup errors around three Cartesian axes were simulated for five prostate patients and dosimetric indices, such as dose-volume histogram (DVH), tumour control probability (TCP), normal tissue complication probability (NTCP) and equivalent uniform dose (EUD), were employed to evaluate the corresponding dosimetric influences. Rotational setup errors were simulated by adjusting the gantry, collimator and horizontal couch angles of treatment beams and the dosimetric effects were evaluated by recomputing the dose distributions in the treatment planning system. Our results indicated that, for prostate cancer treatment with the three-phase sequential boost IMRT technique, the rotational setup errors do not have significant dosimetric impacts on the cumulative plan. Even in the worst-case scenario with DeltaPhi=3 degrees, the prostate EUD varied within 1.5% and TCP decreased about 1%. For seminal vesicle, slightly larger influences were observed. However, EUD and TCP changes were still within 2%. The influence on sensitive structures, such as rectum and bladder, is also negligible. This study demonstrates that the rotational setup error degrades the dosimetric coverage of target volume in prostate cancer treatment to a certain degree. However, the degradation was not significant for the three-phase sequential boost prostate IMRT technique and for the margin sizes used in our institution.

Body Burden↗