The primary controlling factors of the occurrence state of deep high-rank coalbed methane in eastern Ordos Basin

Introduction: This study investigates the key controlling factors of the occurrence state of deep coalbed methane (CBM). CBM is an abundant energy resource in China, particularly in deep coal seams. However, the exploration and development of deep CBM face numerous challenges, and the understanding of the controlling factors of its occurrence state is still limited.Methods: The study reveals that deep CBM primarily exists in the form of adsorbed gas and free gas within the pore-fracture system of coal. Factors such as formation temperature, formation pressure, pore structure, and water saturation collectively influence the occurrence state of deep CBM. By employing the Simplified Local Density (SLD) model and molecular simulation methods.Results and discussion: This study examines the impact of two external geological control factors (formation temperature, formation pressure) and three internal geological control factors (pore size, water saturation, Specific surface area) on deep CBM and establishes a theoretical model for gas content. Finally, the relationship between the adsorbed gas, free gas, total gas content, and burial depth is calculated using the model, uncovering the primary factors controlling the occurrence state of deep CBM. This research is of significant importance in providing key parameters for gas content in deep coal and optimizing deep CBM exploration

Interferon-γ upregulates expression of IFP35 gene in HeLa cells via interferon regulatory factor-1.

BackgroundInterferon-induced 35-kDa protein (IFP35) plays important roles in antiviral defense and the progression of some skin cancer diseases. It can be induced by interferon-γ (IFN-γ) in multiple human cells. However, the mechanisms by which IFN-γ contributes to IFP35 induction remain to be elucidated.Methods/principal findingsWe identified the transcription start sites of IFP35 by 5' rapid amplification of cDNA ends (RACE) and cloned the promoter of IFP35. Sequence analysis and luciferase assays revealed two GC boxes and an IFN-stimulated response element (ISRE) in the 5' upstream region of the transcription start sites, which were important for the basal transcription of IFP35 gene. Furthermore, we found that interferon regulatory factor 1 (IRF-1) and IRF-2 could bind to IFP35 promoter and upregulate endogenous IFP35 protein level. Depletion of endogenous IRF-1 by interfering RNA reduced the constitutive and IFN-γ-dependent expression of IFP35, whereas depletion of IRF-2 had little effect on IFN-γ-inducible IFP35 expression. Moreover, IRF-1 was recruited to the ISRE site in IFP35 promoter in IFN-γ treated HeLa cells, as demonstrated by electrophoretic mobility shift and chromatin immunoprecipitation assays.Conclusions/significanceThese findings provide the first evidence that IRF-1 and IRF-2 are involved in constitutive IFP35 expression in HeLa cells, while IRF-1 also activates IFP35 expression in an IFN-γ-inducible manner. Our data therefore identified a new IRF-1 and IRF-2 target gene, which may expand our current understanding of the versatile functions of IRF-1 and IRF-2

Surface area and local curvature: Why roughness improves the bioactivity of neural implants

While roughening the surface of neural implants has been shown to significantly improve their performance, the mechanism for this improvement is not understood, preventing systematic optimization of surfaces. Specifically, prior work has shown that the cellular response to a surface can be significantly enhanced by coating the implant surface with inorganic nanoparticles and neuroadhesion protein L1, and this improvement occurs even when the surface chemistry is identical between the nanoparticle-coated and uncoated electrodes, suggesting the critical importance of surface topography. Here, we use transmission electron microscopy to characterize the topography of bare and nanoparticle-coated implants across 7 orders of magnitude in size, from the device scale to the atomic scale. The results reveal multi-scale roughness, which cannot be adequately described using conventional roughness parameters. Indeed, the topography is nearly identical between the two samples at the smallest scales and also at the largest scales, but vastly different in the intermediate scales, especially in the range of 5-100 nm. Using a multi-scale topography analysis, we show that the coating causes a 76% increase in the available surface area for contact, and an order-of-magnitude increase in local surface curvature at characteristic sizes corresponding to specific biological structures. These are correlated with a 75% increase in bound proteins on the surface, and a 134% increase in neurite outgrowth. The present investigation presents a framework for analyzing the scale-dependent topography of medical device-relevant surfaces, and suggests the most critical size scales that determine the biological response to implanted materials

Identification and analysis of 5′ promoter region of IFP35 gene.

<p>(<b>A</b>) The ATG translational start site is underlined and the A is designed as +1. Arrowheads indicate the transcriptional start sites. The putative <i>cis</i>-elements are boxed. (<b>B</b>) Schematic representation of six 5′ upstream region deletions of IFP35 gene. (<b>C</b>) Schematic representation of the core promoter region of pGL-359. The mutations were constructed as indicated. (<b>D</b>) HeLa cells were transfected with the indicated promoter constructs. Luciferase assays were performed 48 h after transfection. β-gal activity was measured as a normalization control for the luciferase activity. (<b>E</b>) HeLa cells were transfected with the indicated wild type or mutant pGL-359 constructs. Luciferase assays were performed 48 h after transfection.</p

STAT1 is involved in IFN-γ-induced IFP35 expression in HeLa cells.

<p>(<b>A</b>) pGL-210 was co-transfected with shSTAT1 or shCONr into HeLa cells. At 36 h after transfection, cells were cultured in the presence or absence of IFN-γ (10 ng/ml) for 12 h before luciferase assays were performed. The response to IFN-γ is presented as fold induction relative to unstimulated cells. Data are the mean and standard error from three experiments. ^*P<0.05. (<b>B</b>) HeLa cells stably expressing either shSTAT1 or shCONr were transfected with pCDNA3.1 or pCDNA3.1-IRF-1. At 36 h after transfection, cells were treated with IFN-γ (10 ng/ml) for 12 h before immunoblotting was performed. (<b>C</b>) HeLa cells were treated with IFN-γ (10 ng/ml) for 12 h and processed for ChIP assays by using control IgG, anti-IRF-1 or anti-STAT1. The negative control indicates a genomic fragment (+976 to +1337, relative to the translation start site) downstream of IL-7 promoter.</p

IRF-1 participates in IFP35 transcription by binding directly to the ISRE of the IFP35 promoter <i>in vitro</i>.

<p>(<b>A</b>) pGL-210 or pGL-210mISRE was co-transfected with the empty vector or the IRF-1 expression plasmid into HeLa cells. Luciferase assays were performed at 48 h after transfection. Data are the mean and standard error from three experiments. (<b>B</b>) Schematic diagram of the probes used in EMSA assay. (<b>C</b>) EMSA was performed with GST or GST–IRF-1. Digoxigenin-labeled S93 or S93m were used as probes. Arrowheads indicate DNA–protein complexes. (<b>D</b>) EMSA was performed with GST or GST–IRF-1. Digoxigenin-labeled 3×ISRE or 3×ISREm were used as probes. Arrowheads indicate DNA–protein complexes.</p

IRF-1 binds to IFP35 promoter upon IFN-γ treatment.

<p>(<b>A</b>) HeLa cells were either untreated or treated with IFN-γ (10 ng/ml) for 12 h. Nuclear extracts prepared from these cells were subjected to EMSA. The competitor represents 40×excess cold 3×ISRE. (<b>B</b>) Nuclear extracts (4 µg) from HeLa cells unstimulated or stimulated with IFN-γ (10 ng/ml) for 12 h were subjected to EMSA by using 3×ISRE probe. Supershift assays were performed by preincubating the nuclear extracts with 2 µg anti-IRF-1 or anti-IRF-3. The specific IRF-1 complex and supershifted complex were indicated by arrows. The free probes have run out of the gel. (<b>C</b>) HeLa cells were either untreated or treated with IFN-γ (10 ng/ml) for 12 h and processed for ChIP assays by using anti-IRF-1, anti-IRF-3 or control IgG. Precipitated DNA encompassing the IFP35 ISRE was then assayed by PCR. The negative control indicates a genomic fragment (+976 to +1337, relative to the translation start site) downstream of IL-7 promoter. (<b>D</b>) The experiment was similarly performed as in (C) except that anti-IRF-1 and anti-IRF-2 were used.</p

ISRE is responsible for IFN-γ induced IFP35 promoter activation.

<p>(<b>A</b>) HeLa cells were transfected with pGL-210 or pGL-359 and stimulated with IFN-γ (10 ng/ml) for different time periods. The response to IFN-γ is presented as fold induction relative to pGL3-Basic. (<b>B</b>) HeLa cells were stimulated with IFN-γ (10 ng/ml) for different time periods. The expression of IFP35 and α-tubulin was monitored by Western blot analysis. (<b>C</b>) HeLa cells were transfected with the pGL3-Basic, pGL-210 or pGL-210mISRE constructs. At 36 h after transfecion, cells were incubated with medium alone or with IFN-γ (10 ng/ml) for 12 h before luciferase assays were performed.</p

Primers for PCR of IFP35 promoter fragments and site-directed mutagenesis.

<p>Primers for PCR of IFP35 promoter fragments and site-directed mutagenesis.</p

IFP35 expression is upregulated by constitutively active forms of IRF-3 and IRF-7 in HeLa cells.

<p>HeLa cells were transfected with the expression plasmids encoding IRF-1, IRF-2 and constitutively active forms of IRF-3, IRF-5 and IRF-7. At 48 h after transfection, whole cell extracts were prepared and Western blot analysis was performed with antibodies as indicated.</p