AhR Agonistic Components in Urban Particulate Matter Regulate Astrocytic Activation and Function.

Exposure to atmospheric particulate matter (PM) has been found to accelerate the onset of neurological disorders via the induction of detrimental neuroinflammatory responses. To reveal how astrocytes respond to urban atmospheric PM stimulation, a commercially available standard reference material (SRM1648a) was tested in this study on the activation of rat cortical astrocytes. The results showed that SRM1648a stimulation induced both A1 and A2 phenotypes in astrocytes, as characterized by the exposure concentration-dependent increases in Fkbp5, Sphk1, S100a10, and Il6 mRNA levels. Studying the functional alterations of astrocytes indicated that the neurotrophic factors of Gdnf and Ngf were transcriptionally upregulated due to astrocytic A2-type activation. SRM1648a also promoted autonomous motility of astrocytes and elevated the expressions of chemokines. The aryl hydrocarbon receptor (AhR) agonistic components, such as polycyclic aromatic hydrocarbons (PAHs), were recognized to greatly contribute to SRM1648a-induced effects on astrocytes, which was confirmed by the attenuation of PM-disturbed astrocytic effects via AhR blockage. This study, for the first time, uncovered the direct regulation of urban atmospheric PM on astrocytic activation and function and traced the containing bioactive components (e.g., PAHs) with AhR agonistic activity. The findings provided new knowledge on understanding the ambiguous neurological disturbance from ambient fine PM pollution.

Arsenite S-Adenosylmethionine Methyltransferase Is Responsible for Antimony Biomethylation in Nostoc sp. PCC7120.

Antimony (Sb) biomethylation is an important but uninformed process in Sb biogeochemical cycling. Methylated Sb species have been widely detected in the environment, but the gene and enzyme for Sb methylation remain unknown. Here, we found that arsenite S-adenosylmethionine methyltransferase (ArsM) is able to catalyze Sb(III) methylation. The stepwise methylation by ArsM forms mono-, di-, and trimethylated Sb species. Sb(III) is readily coordinated with glutathione, forming the preferred ArsM substrate which is anchored on three conserved cysteines. Overexpressing arsM in Escherichia coli AW3110 conferred resistance to Sb(III) by converting intracellular Sb(III) into gaseous methylated species, serving as a detoxification process. Methylated Sb species were detected in paddy soil cultures, and phylogenetic analysis of ArsM showed its great diversity in ecosystems, suggesting a high metabolic potential for Sb(III) methylation in the environment. This study shows an undiscovered microbial process methylating aqueous Sb(III) into the gaseous phase, mobilizing Sb on a regional and even global scale as a re-emerging contaminant.

A novel loop-mediated isothermal amplification-lateral flow dipstick method for Helicobacter pylori detection.

Introduction: To eradicate Helicobacter pylori (H. pylori) and reduce the risk of gastric cancer, a sensitive, specific, convenient, and simple detection method is needed. This study aimed to establish a novel loop-mediated isothermal amplification-lateral flow dipstick (LAMP-LFD) method for H. pylori detection. Methods: LAMP primer design software was used to design primers for the conserved sites of the H. pylori ureB gene. UreB-FIP-labeled biotin was used for LAMP amplification, and FAM-labeled probes were specifically hybridized with LAMP amplification products, which were then detected by LFD. In addition, a clinical study was conducted to assess LAMP-LFD in 20 fecal samples. Results: The results of the optimization indicated that H. pylori could be specifically detected by LFD without cross-reaction with other non-H. pylori bacteria when the LAMP was performed at 65°C for 60 min. The lower limit of the detection method was 102 copies/µL, which was 100 times the sensitivity of polymerase chain reaction (PCR). H. pylori-positive fecal samples were detected by LAMP-LFD in 13/20 patients. Discussion: In conclusion, a new LAMP-LFD assay has been fully established and confirmed for H. pylori detection. The entire process can be completed in approximately 1.5 h, with the advantages of strong specificity, high sensitivity, and simple operation. This study provides a novel potential method for the detection of H. pylori in the clinical settings of primary hospitals and low-resource countries.

Genome-Resolved Metagenomics and Metatranscriptomics Reveal that Aquificae Dominates Arsenate Reduction in Tengchong Geothermal Springs.

Elevated arsenic (As) is common in geothermal springs, shaping the evolution of As metabolism genes and As transforming microbes. Herein, genome-level microbial metabolisms and As cycling strategies in Tengchong geothermal springs were demonstrated for the first time based on metagenomic and metatranscriptomic analyses. Sulfur cycling was dominated by Aquificae oxidizing thiosulfate via the sox system, fueling the respiration and carbon dioxide fixation processes. Arsenate reduction via arsC [488.63 ± 271.60 transcripts per million (TPM)] and arsenite efflux via arsB (442.98 ± 284.81 TPM) were the primary detoxification pathway, with most genes and transcripts contributed by the members in phylum Aquificae. A complete arsenotrophic cycle was also transcriptionally active as evidenced by the detection of aioA transcripts and arrA transcript reads mapped onto metagenome-assembled genomes (MAGs) affiliated with Crenarchaeota. MAGs affiliated with Aquificae had great potential of reducing arsenate via arsC and fixing nitrogen and carbon dioxide via nifDHK and reductive tricarboxylic acid (rTCA) cycle, respectively. Aquificae's arsenate reduction potential via arsC was observed for the first time at the transcriptional level. This study expands the diversity of the arsC-based arsenate-reducing community and highlights the importance of Aquificae to As biogeochemistry.

Speciation, leachability and bioaccessibility of tungsten in tungsten ore processing residue.

Tungsten ore processing residue (TOPR) poses a potential risk due to tungsten (W) leaching. However, the leachability of W in TOPR is not well understood. Herein, the mechanism of W leachability from TOPR was investigated using complementary characterization techniques and leaching experiments. Our X-ray absorption near edge structure (XANES) analysis resolved wolframite in TOPR with a distorted octahedral coordination. The sequential extraction procedure showed that 78% of mobile fraction W in TOPR were bound to Fe oxides, and consequently W leachability was positively correlated with dissolved Fe concentration as evidenced by the general acid neutralizing capacity (GANC) test. The GANC results showed that the W release was negatively correlated with Ca concentration due to CaWO4 precipitation. The in vitro gastrointestinal procedure (IVG) results indicated that organic acids, abundant in fruits and vegetables, significantly improved the bioaccessibility of W from 10% to 20% of total W in TOPR. As a consequence, accidental ingestion of TOPR with a chemical daily intake at 0.8 mg kg-1 day-1 evidenced its emerging concern in the environment and human health.

Clinicopathological Characteristics of Primary Appendiceal Mucinous Neoplasm and Recurrence After Radical Resection.

Objective: Appendiceal mucinous neoplasm (AMN) is a rare obstructive dilatation of the appendix caused by an intraluminal accumulation of mucoid material, showing an insidious onset and few specific clinical manifestations. The purpose of the study is to analyze clinicopathological characteristics of primary AMN and recurrence after radical resection. Methods: A total of 50 patients were included in the retrospective cohort study of AMN. Patient data, such as demographics, tumor characteristics, surgical management, preoperative serum carcinoembryonic antigen (CEA), and carcinoembryonic antigen 19-9 (CA19-9) levels, were collected. All patients were followed-up with interval CT scans until the end of December 2021, with overall survival (OS) and progression-free survival (PFS) being calculated. Results: All patients were confirmed as AMN by pathological diagnosis after surgery, including 28 cases (56.00%) of low-grade AMN (LAMN) and 22 cases (44.00%) of non-LAMN. Among 50 patients with AMN, there were 12 cases (24.00%) complicated with pseudomyxoma peritonei (PMP). Higher proportions of patients with pTis, pT3, pT4a, ruptured at presentation, and PMP were found in patients with non-LAMN patients than LAMN (p < 0.05). There was a remarkable difference about preoperative serum CA19-9 levels between patients with LAMN and non-LAMN (p = 0.044). Patients complicated with PMP had a higher proportion of patients with ruptured at presentation than those who were not (p < 0.001). The patients with PMP had increased tumor size compared with those without PMP (p = 0.031). Remarkable differences were observed in terms of preoperative serum CA19-9 (p = 0.009) levels between patients with PMP and without PMP. We performed a multivariate analysis of the presence or absence of PMP and found that ruptured at presentation was found to be a risk factor for PMP in patients with AMN (p = 0.003). The PFS in the patients with PMP and those without was 33.33% (4/12) and 2.63% (1/38), showing a significant difference (P = 0.002). Conclusion: The study demonstrates that ruptured at presentation and PMP may influence the prognosis and survival of patients with AMN.

Structural and mechanistic study of antimonite complexation with organic ligands at the goethite-water interface.

Antimony is a re-emerging contaminant, and its complexation with natural organic matter is rising to ever-increasing levels due to global climate change, which has far-reaching impacts on its environmental fate and mobility. A molecular-level understanding of the interactions between Sb(III) and organic ligands at the solid-liquid interface is of paramount importance in deciphering the effect of these organic ligands. Herein, we identified and characterized Sb(III)-organic ligand complexes in solution and at the goethite-water interface using complementary techniques. The FT-ICR MS, XANES, and DFT calculations show that organic ligands bind Sb(III) through nucleophilic functional groups, such as -COO-, -OH and -HS. The formation of surface ternary Sb(III)-bridging complexes retarded the Sb(III) surface precipitation starting from 3.8 mg-Sb/L to a much higher level at 8.3-13.5 mg-Sb/L. The strong bond between Sb(III) and organic ligands is the key factor to inhibit Sb(III) adsorption, surface precipitation and oxidation under sunlight irradiation. Our results showed the chemical basis for the multifaceted functions of organic ligands in stabilizing trace metalloids such as Sb(III) in the environment.

New polymerized sesquiterpene lactones from Ainsliaea yunnanensis and their activity evaluation.

Two new dimeric and trimeric sesquiterpene lactones (1-2), and nine known sesquiterpene lactones (3-11) were isolated from the EtOAc phase of the ethanolic extract of Ainsliaea yunnanensis. Their structures were identified by NMR, IR and HR-ESIMS spectroscopic methods, and compound 1 was confirmed by single crystal X-ray diffraction experiment. All the compounds were tested for their cytotoxic, anti-microbial and anti-inflammatory activities. Compounds 1, 2, 3, 5, 7, 9 and 11 showed very significant selective cytotoxic activities on MDA-MB-468, PANC-1, HEPG2 or A549 cells. Compounds 6 and 11 showed very significant inhibiting effect on Epicoccum sp. (CPCC 400307), Fusarium solani (CPCC 800013) or Bacillus subtilis. Meanwhile, compounds 6 and 7 can inhibit the NLRP3 inflammasome's activation at the concentration of 10 µM.

Thiolation of trimethylantimony: Identification and structural characterization.

Antimony (Sb), a re-emerging contaminant, has received increasing attentions. The toxicity and mobility of Sb depend on its species. However, little knowledge was available about its multiple chemical species in the environment. Here, we identified and characterized a previously unknown Sb species, trimethylmonothioantimony (TMMTSb). TMMTSb was readily formed when trimethylantimony (TMSb) reacted with sulfide. TMMTSb was separated using HPLC-ICP-MS and further identified by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), and the results show the existence of [SbSC3H10]+, [SbSC3H9Na]+, and [SbSC3H9K]+. The formation of Sb-S bond in TMMTSb was evidenced by the Raman shift at 419 cm-1 compared with that in TMSb. Conclusively, the molecular formula was verified as SbS(CH3)3. Sb LIII-edge X-ray absorption near edge structure (XANES) spectrum revealed a higher intensity of the pre-edge peak at 4137 eV of TMMTSb than that of TMSb. The formation of TMMTSb was observed when the microbiota enriched from hot spring sediments and paddy soil were incubated with TMSb. Sulfate-reducing bacteria may be involved in the formation of TMMTSb. The finding of this thiolated methylantimony species may pave a new avenue for exploring the fate of Sb in the environment.

Immobilization and transformation of co-existing arsenic and antimony in highly contaminated sediment by nano zero-valent iron.

Arsenic (As) and antimony (Sb) are usually coexistent in mine wastes and pose a great threat to human health. The As immobilization by nano zero-valent iron (nZVI) is promising, however, the stabilization for co-occurring As and Sb is not known. Herein, the immobilization and transformation of As and Sb in nZVI-treated sediments were evaluated using complementary leaching experiments and characterization techniques. Raw sediment samples from a gold-antimony deposit revealed the co-existence of ultrahigh As and Sb at 50.3 and 14.9 g/kg, respectively. Leaching results show that As was more efficiently stabilized by nZVI than Sb, which was primarily due to the soluble fraction that was readily absorbed by nZVI of As was higher. As the nZVI treatment proceeds, the oxidation and reduction of As and Sb occur simultaneously as evidenced by XPS analysis. The primary oxidant, hydroxyl radicals, was detected by EPR studies, proving the occurrence of nZVI induced Fenton reaction. This study sheds light on differences in the interaction and immobilization of nZVI with Sb and As in co-contaminated sediments.

Mechanistic study of antimonate reduction by Escherichia coli W3110.

Microbial-assisted antimonate [Sb(V)] reduction immobilizes this redox-sensitive metalloid in the subsurface. Most indigenous aerobes in antimony (Sb)-contaminated areas do not contain Sb(V)-reducing genes but can resist high levels of Sb(V) threat. Herein, to unravel the mechanisms of Sb(V) resistance by aerobes, we used Escherichia coli W3110 as a model aerobe and incubated it with 10 µM Sb(V). We found that strain W3110, without known Sb(V)-reducing genes, was able to reduce Sb(V) to Sb(III). Our transcriptome analysis and reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) results show that the Sb(V) threat at the 10 µM level had a negligible effect on the gene expression of strain W3110. In vitro incubation experiments further indicate that Sb(V) reduction was attributable to extracellular polymeric substances (EPS). Moreover, the three-dimensional excitation-emission matrix fluorescence spectroscopy reveals that the tryptophan-like components in EPS were involved in Sb(V) binding as evidenced by its weakened fluorescence intensity upon Sb(V) addition. The FTIR and XPS analyses indicate that hemiacetal and amide groups in EPS contributed to the reduction of Sb(V). Preculture with 10 µM Sb(V) did not exhibit a significant difference in Sb(V)-reducing capacity, suggesting that Sb(V) stress probably did not stimulate EPS secretion of W3110. Our results highlight the importance of EPS as the first line of defense against toxins, especially for those bacteria without such functional genes.

Efficient organic solar cells with superior stability based on PM6:BTP-eC9 blend and AZO/Al cathode.

Although efficiency over 18% has been achieved, the real application of organic solar cells is still impeded by inferior stability because of degradation and limited studies. Here we report efficient normal structure organic solar cells delivering promising stability under different conditions, based on PM6:BTP-eC9 blend and AZO/Al cathode. The impact of cathode on device stability is systematically studied by screening the leading electron transporting layers i.e., AZO, PFN-Br, PDINN, and metal electrodes (Al and Ag). Strong correlation between cathode and stability is demonstrated. The optimal AZO/Al-cathode device delivers the best efficiency of 15.76%, with shelf-stability of T83 > 1,200 h, thermal stability of T60 > 300 h, and MPP operational stability of T87 > 500 h. As far as we know, this is the best stability achieved for PM6:Y6/derivative cells in literature so far, based on well-studied simple cathode system and without any tailoring/dopant for the active blend.

Quantum Chemical Study of the Carbon Dioxide-Philicity of Surfactants: Effects of Tail Functionalization.

Carbon dioxide (CO2)-philic surfactants have broad application prospects in organic synthesis, fracture-enhanced oil recovery, polymerization, extraction, and other fields and can be used to enhance the viscosity of supercritical CO2 (scCO2). In this work, the relationship between the functional group of the surfactant tail and CO2-philicity is studied from a new perspective using density functional theory. Three common functional group types (fluorinated, oxidative, and methyl groups) were investigated. The analysis of binding energy demonstrates that all three types of functional groups can improve the CO2-philicity of the surfactant. Among these three kinds of functional groups, the strongest interaction with CO2 molecules is observed for oxidative functional groups followed by semifluorinated, fluorinated, and methyl groups. However, the CO2 molecules tend to be adsorbed onto the middle segment of the oxidative group, and the intrusion of the CO2 molecules results in the low solubility of oxidative surfactants. In contrast, fluorinated and methyl groups interact with CO2 at the end of the surfactant tail. As a result, the fluorinated surfactants show the best solubility in CO2. Therefore, the solubility of a surfactant in CO2 is not only related to the interaction strength between the surfactant and CO2, it also depends on the interaction structure. The results of this study provide a new strategy for evaluating surfactant CO2-philicity and provide guidance for the design of surfactants with high solubility in scCO2.

Metagenomic insights into microbial arsenic metabolism in shallow groundwater of Datong basin, China.

Elevated arsenic (As) in groundwater is an urgent environmental problem that has caused serious endemic diseases in Datong basin, China. The fate and toxicity of As are generally regulated by microbial As metabolic processes. However, little is known about the microbial community and As metabolism in Datong basin. Herein, the microbial community structure and As metabolism genes in four wells with different levels of As concentration in Shanyin county were investigated using metagenomics approach. The results showed that the presence of As influenced the microbial communities, and Rhodococcus genus was significantly enriched in elevated As wells. As resistance genes were dominant from low to high As containing wells, and As efflux genes such as arsB and acr3 were positively correlated with As concentrations, suggesting that microbes tend to pump As out of the cell as a strategy for As detoxification. Other environmental factors including oxidation-reduction potential (ORP), total organic carbon (TOC), sulfate, and temperature also played a role in shaping the microbial community structure and As metabolic processes.

Superelectrophilic-Initiated C-H Functionalization at the ß-Position of Thiophenes: A One-Pot Synthesis of trans-Stereospecific Saddle-Shaped Cyclic Compounds.

Superelectrophilic-initiated direct C-H functionalization of thiophenes at the ß-position was developed. A series of trans-stereospecific [2,1-a]-IF-thiophene-fused cyclic compounds (4) with saddle-shaped structure were prepared in 17-30% yields through a one-pot superelectrophilic Friedel-Crafts reaction of dihydroindenofluorene with thiophene derivatives. From the crystal packing analyses of 4a, its skeleton shows both strong intermolecular π-π stacking and C-H···π stacking. Furthermore, the ring-dependent photophysical properties of 4 were confirmed by UV-vis absorption and photoluminescence spectroscopy as well as through the study of their fluorescence quantum yield.

[Effectiveness analysis of induced membrane technique in the treatment of infectious bone defect].

Objective: To evaluate the effectiveness of induced membrane technique in the treatment of infectious bone defect. Methods: Thirty-six patients (37 bone lesions) with infectious bone defects were treated with induced membrane technique between January 2011 and June 2014. There were 28 males and 8 females with an average age of 36 years (range, 20-68 years). All bone defects were post-traumatic infectious bone defect. The bone defect was located at the tibia and fibula in 24 cases (25 bone lesions), at femurs in 6 cases (6 bone lesions), at ulnas and radii in 2 cases (2 bone lesions), at calcanei in 3 cases (3 bone lesions), and at clavicle in 1 case (1 bone lesion). The average time between onset and the treatment of induced membrane technique was 6.2 months (range, 0.5-36.0 months); 15 patients were acute infections (disease duration was less than 3 months). At the first stage, after the removal of internal fixator (applicable for the patients who had internal fixation), complete debridement of infection necrotic bone tissue and surrounding soft tissue was performed and the bone defects were filled with antibiotic-impregnated cement spacers. If the bone was unstable after debridement, external fixator or plaster could be used for stabilization. Patients received sensitive antibiotics postoperatively. At the second stage (usually 6-8 weeks later), the cement spacer were removed, with preservation of the induced membrane formed by the spacer, and filled the bone defect with autologous iliac bone graft within the membrane. Results: The hospitalization time after debridement was 17-30 days (mean, 22.2 days), and the hospitalization time after the second stage was 7-14 days (mean, 10 days). All the flaps healed uneventfully in 16 cases treated with local flap transposition or free flap grafting after debridement. One patient of femur fracture received Ilizarov treatment after recurrence of infection at 11 months after operation; 1 patient of distal femoral fracture received amputation after recurrence of infection at 1 month after operation; 1 patient of distal end of tibia and fibula fractures received ankle arthrodesis after repeated debridements due to the recurrence of infection; 1 patient of tibia and fibula fractures lost to follow-up. The other 32 patients (33 bone lesions) were followed up 1-5 years (mean, 2 years) without infection recurrence, and the infection control rate was 91.7% (33/36). All the patients had bony union, and the healing time was 4-12 months (mean, 7.5 months); no refracture occurred. One patient of femur bone defect had a lateral angulation of 15° and leg discrepancy of 1.5 cm. Superficial pin infection was observed in 7 cases and healed after intensive wound care and oral antibiotics. Adjacent joint function restriction were observed in 6 cases at last follow-up. Conclusion: Induced membrane technique is a simple and reliable technique for the treatment of infectious bone defect. The technique is not limited to the size of the bone defect and the effectiveness is satisfactory.