Molecular Insight into the Electric Field Regulation of N2 and CH4 Adsorption in the Trapdoor ZSM-25 Zeolites.

Controlling gas admission by regulating pore accessibility in porous materials has been a topic of extensive research. Recently, the electric field (E-field) has emerged as an external stimulus to alter the adsorption behavior of some microporous adsorbents. However, the mechanism behind this phenomenon is not yet fully understood. Here, we demonstrate the crucial role of the trapdoor cations of zeolite molecular sieves in E-field-regulated gas adsorption. The E-field activation caused framework expansion and cation deviation, significantly reducing the energy barrier for gas molecules passing through the pore aperture gated by the trapdoor cation. This led to an increase in the N2 adsorption capacity of ZSM-25 and a 60% improvement in N2/CH4 selectivity in the quest for nitrogen rejection for natural gas processing. By combining experimental and computational approaches, we elucidated the influence of E-field activation as a concurrent effect of the reduced heat of adsorption caused by framework expansion and the decrease in the energy barrier resulting from promoted cation oscillation. These findings pave the way for the material design of E-field-regulated adsorption and its application in molecular separation.

Prognostic value of GARS in bladder cancer and its role in the tumor microenvironment.

Background: Bladder cancer (BC), as a common type of cancer, has a poor prognosis, also some common invasive prognostic or therapeutic markers are difficult to obtain, which makes further treatment of BC difficult. Glycyl-tRNA synthetase (GARS), as one of the aminoacyl-tRNA synthetases that charge tRNAs with their cognate amino acids, has been identified as a target in many diseases, including tumors. Methods: Bioassay analysis revealed that GARS was in high expression in most cancer tissues. The expression of GARS gene in BC tissues could assess the prognosis of BC patients, and the expression in urinary extracellular vesicles (uEVs) of patients was positively correlated with the expression in tissues. In addition to this, we analyzed GARS-related differential gene expression, copy number variation (CNV) and mutation profiles, potential biological functions, immune cell infiltration and drug sensitivity. In vivo and vitro tumorigenic experiments were performed to validate the function of GARS. Single-cell data were used to further analyze its role in the microenvironment. Results: In our study, we found that GARS was highly expressed in 30 cancer tissues including BC, and high GARS expression was negatively correlated with the prognosis of BC patients. To address this phenomenon, we analyzed the differential genes between high and low GARS groups by enrichment analysis, and identified the biological signaling pathways that were mainly enriched for their functions, and found that the enrichment was found in immune-related signaling pathways and regulation of cell-cell adhesion. Then we found that GARS was positively associated with immune cell infiltration in BC, and some common immune checkpoints were significantly overexpressed in the GARS-high group. Besides, we found that GARS was enriched in myofibroblasts in the tumor microenvironment, and the enrichment was positively correlated with epithelial-mesenchymal transition (EMT)-related genes. This study also showed a positive correlation between GARS and BC RNA stemness. Patients in the GARS-high group had considerably higher rates of P53 and Titin (TTN) mutations than those in the GARS-low group. Drug Sensitivity analysis screened for drugs that were more sensitive to GARS-high patients. Further, we found that knockdown of GARS significantly inhibited the proliferation, migration and invasion ability both in vivo and in vitro. Finally, we found that in patients with high GARS the expression in uEVs was also at a high level. Conclusions: In summary, this study provided evidence that GARS can be used as a prognostic and therapeutic marker for BC, we can detect GARS in uEVs instead of tissue, to provide a new, simple, noninvasive way to obtain prognostic and therapeutic markers for BC patients.

Regulating adsorption performance of zeolites by pre-activation in electric fields.

While multiple external stimuli (e.g., temperature, light, pressure) have been reported to regulate gas adsorption, limited studies have been conducted on controlling molecular admission in nanopores through the application of electric fields (E-field). Here we show gas adsorption capacity and selectivity in zeolite molecular sieves can be regulated by an external E-field. Through E-field pre-activation during degassing, several zeolites exhibited enhanced CO2 adsorption and decreased CH4 and N2 adsorptions, improving the CO2/CH4 and CO2/N2 separation selectivity by at least 25%. The enhanced separation performance of the zeolites pre-activated by E-field was maintained in multiple adsorption/desorption cycles. Powder X-ray diffraction analysis and ab initio computational studies revealed that the cation relocation and framework expansion induced by the E-field accounted for the changes in gas adsorption capacities. These findings demonstrate a regulation approach to sharpen the molecular sieving capability by E-fields and open new avenues for carbon capture and molecular separations.

Development and validation of a nomogram for predicting osteoporosis in prostate cancer patients: A cross-sectional study from China.

BACKGROUND: The specific risk factors contributing to the development of osteoporosis and the appropriate timing of treatment in Chinese prostate cancer (PCa) patients remain unclear. Our objective was to develop and validate a nomogram capable of predicting the occurrence of osteoporosis in PCa patients. METHODS: We conducted a cross-sectional study with PCa patients attending the Second Hospital of Tianjin Medical University, collecting data from June 2021 to February 2023. The patients were divided into training and validation sets in a 7:3 ratio. The LASSO regression was used to identify the most relevant predictive variables, and the multivariable logistic regression was used to construct the nomogram. The nomogram's performance was validated through receiver operating characteristic (ROC) curves, C-index, calibration curves, and decision curve analysis (DCA) in both the training and validation sets. RESULTS: We collected data from a total of 596 patients and then constructed the nomogram using age, body mass index, hemoglobin, vitamin D3, testosterone, and androgen deprivation therapy duration. The C-index of the nomogram was 0.923 in the training set and 0.859 in the validation set. The nomogram showed good consistency in both sets. DCA demonstrated the clinical benefit of the nomogram across various prediction thresholds. Furthermore, a separate nomogram was constructed to predict bone loss in patients undergoing ADT, exhibiting equally favorable diagnostic performance and clinical benefit. CONCLUSION: This study constructed two reliable nomograms to predict osteoporosis and bone loss, integrating personal health information and PCa-specific treatment data. These nomograms offer an easy and individualized approach to predict the occurrence of osteoporosis and bone loss in PCa patients.

Comprehensive analysis of predictive factors for upstaging in intraprostatic cancer after radical prostatectomy: Different patterns of spread exist in lesions at different locations.

BACKGROUND: Accurate assessment of the clinical staging is crucial for determining the need for radical prostatectomy (RP) in prostate cancer (PCa). However, the current methods for PCa staging may yield incorrect results. This study aimed to comprehensively analyze independent predictors of postoperative upstaging of intraprostatic cancer. METHODS: We conducted a retrospective analysis of data from intraprostatic cancer patients who underwent radical surgery between March 2019 and December 2022. Intraprostatic cancer was defined as a lesion confined to the prostate, excluding cases where multiparameter magnetic resonance imaging (mpMRI) showed the lesion in contact with the prostatic capsule. We assessed independent predictors of extraprostatic extension (EPE) and analyzed their association with positive surgical margin (PSM) status. In addition, based on the distance of the lesion from the capsule on mpMRI, we divided the patients into non-transition zone and transition zone groups for further analysis. RESULTS: A total of 500 patients were included in our study. Logistic regression analysis revealed that biopsy Gleason grade group (GG) (odds ratio, OR: 1.370, 95% confidence interval, CI: 1.093-1.718) and perineural invasion (PNI) (OR: 2.746, 95% CI: 1.420-5.309) were predictive factors for postoperative EPE. Both biopsy GG and PNI were associated with lateral (GG: OR: 1.270, 95% CI: 1.074-1.501; PNI: OR: 2.733, 95% CI: 1.521-4.911) and basal (GG: OR: 1.491, 95% CI: 1.194-1.862; PNI: OR: 3.730, 95% CI: 1.929-7.214) PSM but not with apex PSM (GG: OR: 1.176, 95% CI: 0.989-1.399; PNI: OR: 1.204, 95% CI: 0.609-2.381) after RP. Finally, PNI was an independent predictor of EPE in the transition zone (OR: 11.235, 95% CI: 2.779-45.428) but not in the non-transition zone (OR: 1.942, 95% CI: 0.920-4.098). CONCLUSION: PNI and higher GG may indicate upstaging of tumors in patients with intraprostatic carcinoma. These two factors are associated with PSM in locations other than the apex of the prostate. Importantly, cancer in the transition zone of the prostate is more likely to spread externally through nerve invasion than cancer in the non-transition zone.

Screening of Alkali Metal-Exchanged Zeolites for Nitrogen/Methane Separation.

Methane (CH4) is the primary component of natural gas and must be purified to a certain level before it can be used as pipeline gas or liquified natural gas (LNG). In particular, nitrogen (N2), a common contaminant in natural gas needs to be rejected to increase the heating value of the gas and meet the LNG product specifications. The development of energy-efficient N2 removal technologies is hampered by N2's inertness and its resemblance to CH4 in terms of kinetic size and polarizability. N2-selective materials are so rare. Here, for the first time, we screened 1425 alkali metal cation exchange zeolites to identify the candidates with the best potential for the separation of N2 from CH4. We discovered a few extraordinary zeolite frameworks capable of achieving equilibrium selectivity toward N2. Particularly, Li+-RRO-3 zeolite with a specific two-dimensional structure demonstrated a selective N2 adsorption capacity of 2.94 mmol/g at 283 K and 1 bar, outperforming the capacity of all known zeolites. Through an ab initio density functional theory study, we found that the five-membered ring of the RRO framework is the most stable cationic site for Li+, and this Li+ can interact with multiple N2 molecules but only one CH4, revealing the mechanism for the high capacity and selectivity of N2. This work suggests promising adsorbents to enable N2 rejection from CH4 in the gas industry without going for energy-intensive cryogenic distillations.

Hydrogen production from the air.

Green hydrogen produced by water splitting using renewable energy is the most promising energy carrier of the low-carbon economy. However, the geographic mismatch between renewables distribution and freshwater availability poses a significant challenge to its production. Here, we demonstrate a method of direct hydrogen production from the air, namely, in situ capture of freshwater from the atmosphere using hygroscopic electrolyte and electrolysis powered by solar or wind with a current density up to 574 mA cm-2. A prototype of such has been established and operated for 12 consecutive days with a stable performance at a Faradaic efficiency around 95%. This so-called direct air electrolysis (DAE) module can work under a bone-dry environment with a relative humidity of 4%, overcoming water supply issues and producing green hydrogen sustainably with minimal impact to the environment. The DAE modules can be easily scaled to provide hydrogen to remote, (semi-) arid, and scattered areas.

Electrical Regulation of CO2 Adsorption in the Metal-Organic Framework MIL-53.

Active regulation of pore accessibility in microporous materials by external stimuli has aroused great attention in recent years. Here, we show the first experimental proof that guest adsorption in a dielectric microporous material can be regulated by a moderate external E-field below the gas breakdown voltage. CO2 adsorption capacity in MIL-53 (Al) was significantly reduced, whereas that of NH2-MIL-53 (Al) changed insignificantly under a direct current E-field gradient of 286 V/mm. Ab initio DFT calculations revealed that the E-field decreased the charge transfer between the CO2 molecule and the adsorption site in the MIL-53 framework, which resulted in reduced binding energy and consequently lowered CO2 adsorption capacity. This effect was only observed in the narrow pore state MIL-53 (Al) but not in its large pore configuration. Our results demonstrate the feasibility of regulating the adsorption of gas molecules in microporous materials using moderate E-fields.

Gating effect for gas adsorption in microporous materials-mechanisms and applications.

In the past two decades, various microporous materials have been developed as useful adsorbents for gas adsorption for a wide range of industries. Considerable efforts have been made to regulate the pore accessibility in microporous materials for the manipulation of guest molecules' admission and release. It has long been known that some microporous adsorbents suddenly become highly accessible to guest molecules at specific conditions, e.g., above a threshold pressure or temperature. This anomalous adsorption behavior results from a gating effect, where a structural variation of the adsorbent leads to an abrupt change in the gas admission. This review summarizes the mechanisms of the gating effect, which can be a result of the deformation of the framework (e.g., expansion, contraction, reorientation, and sliding of the unit cells), the vibration of the pore-keeping groups (e.g., rotation, swing, and collapse of organic linkers), and the oscillation of the pore-keeping ions (e.g. cesium, potassium, etc.). These structural variations are induced either by the host-guest interaction or by an external stimulus, such as temperature or light, and account for the gating effect at a threshold value of the stimulus. Emphasis is given to the temperature-regulated gating effect, where the critical admission temperature is dictated by the combined effect of the gate opening and thermodynamic factors and plays a key role in regulating guest admission. Molecular simulations can improve our understanding of the gate opening/closing transitions at the atomic scale and enable the construction of quantitative models to describe the gated adsorption behaviour at the macroscale level. The gating effect in porous materials has been widely applied in highly selective gas separation and offers great potential for gas storage and sensing.

Association between visceral adiposity index and risk of prediabetes: A meta-analysis of observational studies.

BACKGROUND AND OBJECTIVE: Epidemiological studies suggested that the association between the visceral adiposity index (VAI) and the risk of prediabetes is inconsistent. Whether VAI is a useful predictor of prediabetes remains unclear. Up until April 2021, there had been no systematic review on this topic. In this meta-analysis, the available observational epidemiological evidence was synthesized to identify the association between VAI and prediabetes risk. METHODS: PubMed, EMBASE, and Cochrane databases in any language were searched systematically from the earliest available online indexing year to April 2021 for relevant observational studies published on the association between VAI and the risk of prediabetes. A random effects model was used to combine quantitatively the odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Ten relevant studies (2 cohort study, 2 case-control studies, and 6 cross-sectional studies) involving 112,603 participants were identified. Compared with the highest VAI, the lowest level of VAI was associated with an increased risk of prediabetes. The pooled OR of VAI for prediabetes was 1.68 (95% CI: 1.44-1.96), with significant heterogeneity across the included studies (P = 0.000, I2 = 91.4%). Exclusion of any single study did not materially alter the combined risk estimate. CONCLUSIONS: Integrated epidemiological evidence supports the hypothesis that VAI is a lipid combined anthropometric index and may be a risk factor for prediabetes. VAI may be related to a high risk of prediabetes. However, it should be noted that the included studies have a publication bias and there was significant heterogeneity between our pooled estimate.

Nitrogen Rejection from Methane via a "Trapdoor" K-ZSM-25 Zeolite.

Nitrogen (N2) rejection from methane (CH4) is the most challenging step in natural gas processing because of the close similarity of their physical-chemical properties. For decades, efforts to find a functioning material that can selectively discriminate N2 had little outcome. Here, we report a molecular trapdoor zeolite K-ZSM-25 that has the largest unit cell among all zeolites, with the ability to capture N2 in favor of CH4 with a selectivity as high as 34. This zeolite was found to show a temperature-regulated gas adsorption wherein gas molecules' accessibility to the internal pores of the crystal is determined by the effect of the gas-cation interaction on the thermal oscillation of the "door-keeping" cation. N2 and CH4 molecules were differentiated by different admission-trigger temperatures. A mild working temperature range of 240-300 K was determined wherein N2 gas molecules were able to access the internal pores of K-ZSM-25 while CH4 was rejected. As confirmed by experimental, molecular dynamic, and ab initio density functional theory studies, the outstanding N2/CH4 selectivity is achieved within a specific temperature range where the thermal oscillation of door-blocking K+ provides enough space only for the relatively smaller molecule (N2) to diffuse into and through the zeolite supercages. Such temperature-regulated adsorption of the K-ZSM-25 trapdoor zeolite opens up a new approach for rejecting N2 from CH4 in the gas industry without deploying energy-intensive cryogenic distillation around 100 K.

Production of γ-aminobutyric acid in Escherichia coli by engineering MSG pathway.

The compound γ-aminobutyric acid (GABA) has many important physiological functions. The effect of glutamate decarboxylases and the glutamate/GABA antiporter on GABA production was investigated in Escherichia coli. Three genes, gadA, gadB, and gadC were cloned and ligated alone or in combination into the plasmid pET32a. The constructed plasmids were transformed into Escherichia coli BL21(DE3). Three strains, E. coli BL21(DE3)/pET32a-gadA, E. coli BL21(DE3)/pET32a-gadAB and E. coli BL21(DE3)/pET32a-gadABC were selected and identified. The respective titers of GABA from the three strains grown in shake flasks were 1.25, 2.31, and 3.98 g/L. The optimal titer of the substrate and the optimal pH for GABA production were 40 g/L and 4.2, respectively. The highest titer of GABA was 23.6 g/L at 36 h in batch fermentation and was 31.3 g/L at 57 h in fed-batch fermentation. This study lays a foundation for the development and use of GABA.

Biogas production from hydrothermal liquefaction wastewater (HTLWW): Focusing on the microbial communities as revealed by high-throughput sequencing of full-length 16S rRNA genes.

Hydrothermal liquefaction (HTL) is an emerging and promising technology for the conversion of wet biomass into bio-crude, however, little attention has been paid to the utilization of hydrothermal liquefaction wastewater (HTLWW) with high concentration of organics. The present study investigated biogas production from wastewater obtained from HTL of straw for bio-crude production, with focuses on the analysis of the microbial communities and characterization of the organics. Batch experiments showed the methane yield of HTLWW (R-HTLWW) was 184 mL/g COD, while HTLWW after petroleum ether extraction (PE-HTLWW), to extract additional bio-crude, had higher methane yield (235 mL/g COD) due to the extraction of recalcitrant organic compounds. Sequential batch experiments further demonstrated the higher methane yield of PE-HTLWW. LC-TOF-MS, HPLC and gel filtration chromatography showed organics with molecular weight (MW) < 1000 were well degraded. Results from the high-throughput sequencing of full-length 16S rRNA genes analysis showed similar microbial community compositions were obtained for the reactors fed with either R-HTLWW or PE-HTLWW. The degradation of fatty acids were related with Mesotoga infera, Syntrophomonas wolfei et al. by species level identification. However, the species related to the degradation of other compounds (e.g. phenols) were not found, which could be due to the presence of uncharacterized microorganisms. It was also found previously proposed criteria (97% and 98.65% similarity) for species identification of 16S rRNA genes were not suitable for a fraction of 16S rRNA genes.

Separation of high-purity syringol and acetosyringone from rice straw-derived bio-oil by combining the basification-acidification process and column chromatography.

Numerous technologies have been used to reclaim valuable chemicals from bio-oil. In this study, a combination of the basification-acidification process and column chromatography was employed for the separation of high-purity syringol and acetosyringone from rice straw-derived bio-oil. The optimal conditions for the basification-acidification process and the possible precipitation mechanism of the basification were explored. The results showed the following as the optimal conditions for the basification process: mass ratio of calcium hydroxide (Ca(OH)2 ) to bio-oil, 2.0; reaction temperature, 70°C; and reaction time, 30 min. The results also showed that 1.6 mol of hydrochloric acid (HCl) per gram of bio-oil was optimal for the acidification. The precipitation was found to proceed via a possible mechanism involving the reaction of the phenolic compounds in the bio-oil with Ca(OH)2 to produce a precipitate. After further separation by column chromatography, purities of 91.4 and 96.2% (from gas chromatography-mass spectrometry) were obtained for syringol and acetosyringone, respectively. Their recoveries for the whole process were 73.0 and 39.3%, respectively.

Separation of phenolic compounds with modified adsorption resin from aqueous phase products of hydrothermal liquefaction of rice straw.

Hydrothermal liquefaction can be used to convert rice straw into an aqueous phase product that contains valuable phenolic compounds. In experiments, commercial adsorption resin XAD-4 was modified by a benzene ring - α,α'-dichloro-p-xylene (DCX) - in order to separate the phenolic compounds from the aqueous phase product; and, the optimal conditions for separation were explored. The results showed that, after modification of the resin, its adsorption capacity improved by 50%, due to increases in surface area, pore volume and micropore volume. The selectivity of the resin increased when the benzene ring was introduced as the ring formed hydrogen bonds with the compounds. The optimal conditions for separation were desorption agent of 40%, 45% and 55% ethanol solution, a flow rate of 2.5-5 mL/min, and a ratio of the sample volume to the column volume was 1:1. The total content of phenolic compounds in aqueous solution increased from 18% to 78% after separation.

Improving the secretory production of the heterologous protein in Pichia pastoris by focusing on protein folding.

Pichia pastoris has currently been developed as an effective host system for the expression of heterologous genes owing to its potential use for the production of soluble and high-yield proteins. However, the secretory production of the different heterologous proteins in P. pastoris varies widely. Some factors restrict the effective secretory production of heterologous proteins in P. pastoris, among which the folding and processing of proteins is a major one. Besides optimizing the fermentative process, current strategies focus on investigating protein folding process. Thus, this paper is the first time to review the improvement of the secretory production of the heterologous protein in P. pastoris by focusing on its folding process.

[Diet-induced obesity increases the apoptosis of testicular spermatogenic cells in pubertal male rats].

OBJECTIVE: To investigate the effect of diet-induced obesity on the apoptosis of testicular spermatogenic cells in pubertal male rats. METHODS: Forty healthy male rats were equally and randomly divided into a control and a high-fat group, the former fed on normal diet, while the latter high-fat and high-calorie diet. The testes of the rats were harvested at the end of 10 weeks for detection of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) in the peripheral blood with the automatic biochemical analyzer. Pathological changes of the testis were observed under the light microscope, the apoptosis of the testicular cells detected by TUNEL, the expressions of Bcl-2 and Bax proteins determined by immunohistochemistry, and those of Bcl-2 mRNA and Bax mRNA measured by RT-PCR. RESULTS: The levels of TC, TG, LDL-C and HDL-C were significantly higher in the high-fat group (5.17 +/- 0.17, 1.18 +/- 0.09, 1.76 +/- 0.11 and 5.08 +/- 0.18) than in the control (1.38 +/- 0.12, 0.39 +/- 0.05, 0.97 +/- 0.07 and 0.75 +/- 0.06) (P < 0.05), so was the apoptotic index of spermatogenic cells (37.17 +/- 2.74 versus 5.16 +/- 0.81, P < 0.01), and the apoptotic spermatogenic cells were mainly spermatogonia and spermatocytes. The expressions of Bax protein and Bax mRNA were markedly higher in the high-fat group (153.26 +/- 8.74 and 1.08 +/- 0.12) than in the control (101.81 +/- 6.14 and 0.37 +/- 0.04) (P < 0.01), while those of Bcl-2 protein and Bcl-2 mRNA remarkably lower in the former (139.26 +/- 7.21 and 0.46 +/- 0.05) than in the latter (159.37 +/- 8.96 and 1.05 +/- 0.11) (P < 0.01). CONCLUSION: Diet-induced obesity can increase the apoptosis of spermatogenic cells in the rat testis, which may be associated with the reduced expression of Bcl-2 and elevated expression of Bax.