Genomic instability-associated two-miRNA signature as a novel prognostic biomarker in breast cancer.

BACKGROUND: Breast cancer (BC) is the most common cancer among women worldwide and a leading cause of cancer-associated deaths among women. However, there is a lack of accurate prognostic biomarkers for BC. In the present study, we aimed to identify a genomic instability (GI)-associated microRNA signature as a novel potential prognostic biomarker in BC. METHODS: We performed an integrative analysis to investigate the relationship between GI and BC and identify GI-associated microRNAs (miRNAs). Subsequently, we conducted a discovery and validation study using multicenter cohorts. The GI-associated miRNA signature was developed in the discovery cohort and independently validated in internal and external cohorts. RESULTS: GI-associated miRNAs expression in BC showed heterogeneity and was significantly correlated with BC prognosis. We identified a GI-associated two-miRNA signature (miR-105-5p and miR-767-5p), termed GI2miR, that stratified BC patients into high-risk and low-risk groups with significantly different clinical outcomes (log-rank p = 0.027) in The Cancer Genome Atlas (TCGA) discovery cohort (n = 763). The prognostic value of GI2miR was further validated in internal TCGA validation cohort (n = 253) (log-rank p = 0.035) and independent GSE22216 cohort (n = 210) (log-rank p = 0.036). The GI2miR demonstrated independent prognostic value in multivariate Cox proportional hazard regression analyses and stratification analysis. CONCLUSIONS: We have developed a novel prognostic signature based on GI-associated two miRNAs for BC, which may lay the foundation for BC to improve prognosis prediction.

Dissection of the antitumor mechanism of tetrandrine based on metabolite profiling and network pharmacology.

RATIONALE: Tetrandrine, the Q-marker in Stephaniae Tetrandrae Radix, was proven to present an obvious antitumor effect. Until now, the metabolism and antitumor mechanism of tetrandrine have not been fully elucidated. METHODS: The metabolites of tetrandrine in rats were profiled using ultra-high-performance liquid chromatography coupled with time-of-flight mass spectrometry. The potential antitumor mechanism of tetrandrine in vivo was predicted using network pharmacology. RESULTS: A total of 30 metabolites were characterized in rats after ingestion of tetrandrine (10 mg/kg), including 0 in plasma, 7 in urine, 11 in feces, 9 in liver, 8 in spleen, 4 in lung, 5 in kidney, 5 in heart, and 4 in brain. This study was the first to show the metabolic processes demethylation, hydroxylation, and carbonylation in tetrandrine. The pharmacology network results showed that tetrandrine and its metabolites could regulate AKT1, TNF, MMP9, MMP2, PAK1, and so on by involving in proteoglycan tumor pathway, PI3K-Akt signaling pathway, tumor pathway, MAPK signaling pathway, and Rap1 signaling pathway. CONCLUSIONS: The metabolism features of tetrandrine and its potential antitumor mechanism were summarized, providing data for further pharmacological validation.

Core taxa, co-occurrence pattern, diversity, and metabolic pathways contributing to robust anaerobic biodegradation of chlorophenol.

It is hard to achieve robustness in anaerobic biodegradation of trichlorophenol (TCP). We hypothesized that specific combinations of environmental factors determine phylogenetic diversity and play important roles in the decomposition and stability of TCP-biodegrading bacteria. The anaerobic bioreactor was operated at 35 °C (H condition) or 30 °C (L condition) and mainly fed with TCP (from 28 µM to 180 µM) and organic material. Metagenome sequencing was combined with 16S rRNA gene amplicon sequencing for the microbial community analysis. The results exhibited that the property of robustness occurred in specific conditions. The corresponding co-occurrence and diversity patterns suggest high collectivization, degree and evenness for robust communities. Two types of core functional taxa were recognized: dechlorinators (unclassified Anaerolineae, Thermanaerothrix and Desulfovibrio) and ring-opening members (unclassified Proteobacteria, Methanosarcina, Methanoperedens, and Rubrobacter). The deterministic process of the expansion of niche of syntrophic bacteria at higher temperatures was confirmed. The reductive and hydrolytic dechlorination mechanisms jointly lead to C-Cl bond cleavage. H ultimately adapted to the stress of high TCP loading, with more abundant ring-opening enzyme (EC 3.1.1.45, ∼55%) and hydrolytic dechlorinase (EC 3.8.1.5, 26.5%) genes than L (∼47%, 10.5%). The functional structure (based on KEGG) in H was highly stable despite the high loading of TCP (up to 60 µM), but not in L. Furthermore, an unknown taxon with multiple functions (dechlorinating and ring-opening) was found based on genetic sequencing; its functional contribution of EC 3.8.1.5 in H (26.5%) was higher than that in L (10.5%), and it possessed a new metabolic pathway for biodegradation of halogenated aromatic compounds. This new finding is supplementary to the robust mechanisms underlying organic chlorine biodegradation, which can be used to support the engineering, regulation, and design of synthetic microbiomes.

Lag effect of ambient temperature on respiratory emergency department visits in Beijing: a time series and pooled analysis.

BACKGROUND: Although the association between ambient temperature and mortality of respiratory diseases was numerously documented, the association between various ambient temperature levels and respiratory emergency department (ED) visits has not been well studied. A recent investigation of the association between respiratory ED visits and various levels of ambient temperature was conducted in Beijing, China. METHODS: Daily meteorological data, air pollution data, and respiratory ED visits data from 2017 to 2018 were collected in Beijing. The relationship between ambient temperature and respiratory ED visits was explored using a distributed lagged nonlinear model (DLNM). Then we performed subgroup analysis based on age and gender. Finally, meta-analysis was utilized to aggregate the total influence of ambient temperature on respiratory ED visits across China. RESULTS: The single-day lag risk for extreme cold peaked at a relative risk (RR) of 1.048 [95% confidence interval (CI): 1.009, 1.088] at a lag of 21 days, with a long lag effect. As for the single-day lag risk for extreme hot, a short lag effect was shown at a lag of 7 days with an RR of 1.076 (95% CI: 1.038, 1.114). The cumulative lagged effects of both hot and cold effects peaked at lag 0-21 days, with a cumulative risk of the onset of 3.690 (95% CI: 2.133, 6.382) and 1.641 (95% CI: 1.284, 2.098), respectively, with stronger impact on the hot. Additionally, the elderly were more sensitive to ambient temperature. The males were more susceptible to hot weather than the females. A longer cold temperature lag effect was found in females. Compared with the meta-analysis, a pooled effect of ambient temperature was consistent in general. In the subgroup analysis, a significant difference was found by gender. CONCLUSIONS: Temperature level, age-specific, and gender-specific effects between ambient temperature and the number of ED visits provide information on early warning measures for the prevention and control of respiratory diseases.

The safety of remimazolam versus propofol in gastroscopic sedation: a meta-analysis.

BACKGROUND: This meta-analysis was designed to compare the safety and efficiency of remimazolam with those of propofol in patients undergoing gastroscope sedation. METHODS: We searched PubMed, Cochrane Library, Embase, Ovid, Wanfang Database, China National Knowledge Infrastructure, SINOMED, and ClinicalTrials.gov for studies that reported on remimazolam versus propofol for gastroscope sedation from establishment to February 25, 2023. The sedative efficiency and the incidence of adverse events were assessed as outcomes. Version 2 of the Cochrane risk-of-bias assessment tool was used to assess the risk of bias. Review Manager 5.4 and STATA 17 were used to perform all statistical analyses. RESULTS: A total of 26 randomized controlled trials involving 3,641 patients were included in this meta-analysis. The results showed that remimazolam had a significantly lower incidence of respiratory depression (risk ratio [RR] = 0.40, 95% confidence interval [CI]: 0.28-0.57; p < 0.01, GRADE high), hypoxemia (RR = 0.34, 95% CI: 0.23-0.49; p < 0.01, GRADE high), bradycardia (RR = 0.34, 95% CI: 0.23-0.51; p < 0.01, GRADE high), dizziness (RR = 0.45, 95% CI: 0.31-0.65; p < 0.01, GRADE high), injection site pain (RR = 0.06, 95% CI: 0.03-0.13; p < 0.01, GRADE high), nausea or vomiting (RR = 0.79, 95% CI: 0.62-1.00; p = 0.05, GRADE moderate), and hypotension (RR = 0.36, 95% CI: 0.26-0.48; p < 0.01, GRADE low). CONCLUSIONS: Remimazolam can be used safely in gastroscopic sedation and reduces the incidence of respiratory depression, hypoxemia, bradycardia, injection site pain, and dizziness compared with propofol, and doesn't increase the incidence of nausea and vomiting.

New horizons for the role of selenium on cognitive function: advances and challenges.

Cognitive deficits associated with oxidative stress and the dysfunction of the central nervous system are present in some neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease. Selenium (Se), an essential microelement, exhibits cognition-associated functions through selenoproteins mainly owing to its antioxidant property. Due to the disproportionate distribution of Se in the soil, the amount of Se varies greatly in various foods, resulting in a large proportion of people with Se deficiency worldwide. Numerous cell and animal experiments demonstrate Se deficiency-induced cognitive deficits and Se supplementation-improved cognitive performances. However, human studies yield inconsistent results and the mechanism of Se in cognition still remains elusive, which hinder the further exploration of Se in human cognition. To address the urgent issue, the review summarizes Se-contained foods (plant-based foods, animal-based foods, and Se supplements), brain selenoproteins, mechanisms of Se in cognition (improvement of synaptic plasticity, regulation of Zn2+ level, inhibition of ferroptosis, modulation of autophagy and de novo synthesis of L-serine), and effects of Se on cognitive deficits, as well as consequently sheds light on great potentials of Se in the prevention and treatment of cognitive deficits.

Medium-term exposure to size-fractioned particulate matter and asthma exacerbations in China: A longitudinal study of asthmatics with poor medication adherence.

BACKGROUND: Studies have shown that short- and long-term exposure to particulate matter (PM) can increase the risk of asthma morbidity and mortality. However, the effect of medium-term exposure remains unknown. We aim to examine the effect of medium-term exposure to size-fractioned PM on asthma exacerbations among asthmatics with poor medication adherence. METHODS: We conducted a longitudinal study in China based on the National Mobile Asthma Management System Project that specifically and routinely followed asthma exacerbations in asthmatics with poor medication adherence from April 2017 to May 2019. High-resolution satellite remote-sensing data were used to estimate each participant's medium-term exposure (on average 90 days) to size-fractioned PM (PM1, PM2.5, and PM10) based on the residential address and the date of the follow-up when asthma exacerbations (e.g., hospitalizations and emergency room visits) occurred or the end of the follow-up. The Cox proportional hazards model was employed to examine the hazard ratio of asthma exacerbations associated with each PM after controlling for sex, age, BMI, education level, geographic region, and temperature. RESULTS: Modelling results revealed nonlinear exposure-response associations of asthma exacerbations with medium-term exposure to PM1, PM2.5, and PM10. Specifically, for emergency room visits, we found an increased hazard ratio for PM1 above 22.8 µg/m3 (1.060, 95 % CI: 1.025-1.096, per 1 µg/m3 increase), PM2.5 above 38.2 µg/m3 (1.032, 95 % CI: 1.010-1.054), and PM10 above 78.6 µg/m3 (1.019, 95 % CI: 1.006-1.032). For hospitalizations, we also found an increased hazard ratio for PM1 above 20.3 µg/m3 (1.055, 95 % CI: 1.001-1.111) and PM2.5 above 39.2 µg/m3 (1.038, 95 % CI: 1.003-1.074). Furthermore, the effects of PM were greater for a longer exposure window (90-180 days) and among participants with a high BMI. CONCLUSION: This study suggests that medium-term exposure to PM is associated with an increased risk of asthma exacerbations in asthmatics with poor medication adherence, with a higher risk from smaller PM.

Single-junction organic solar cells with over 19% efficiency enabled by a refined double-fibril network morphology.

In organic photovoltaics, morphological control of donor and acceptor domains on the nanoscale is the key for enabling efficient exciton diffusion and dissociation, carrier transport and suppression of recombination losses. To realize this, here, we demonstrated a double-fibril network based on a ternary donor-acceptor morphology with multi-length scales constructed by combining ancillary conjugated polymer crystallizers and a non-fullerene acceptor filament assembly. Using this approach, we achieved an average power conversion efficiency of 19.3% (certified 19.2%). The success lies in the good match between the photoelectric parameters and the morphological characteristic lengths, which utilizes the excitons and free charges efficiently. This strategy leads to an enhanced exciton diffusion length and a reduced recombination rate, hence minimizing photon-to-electron losses in the ternary devices as compared to their binary counterparts. The double-fibril network morphology strategy minimizes losses and maximizes the power output, offering the possibility of 20% power conversion efficiencies in single-junction organic photovoltaics.

Effect of LGR4/EGFR signaling on cell growth and cancer stem cell-like characteristics in liver cancer.

PURPOSE: Hepatocellular carcinoma (HCC) is the most common primary liver cancer. Leucine-rich repeat containing G-protein-coupled receptors 4 (LGR4) participates in tumor progression, invasion, and metastasis. Our study aimed to investigate the effect of LGR4 with epidermal growth factor receptor (EGFR) in HCC cells. METHODS: We employed Hep3B and Huh7 cells to conduct our research. Comprehensive biological activities were characterized by CCK8 and transwell assay. Molecular biology techniques were used to determine the expression of proteins. Hep3B was employed to conduct subcutaneous tumor in mice. The tumor growth and the expression levels of proteins were assessed. RESULTS: LGR4 overexpression could promote the cells proliferation, migration, and invasion ability, while siLGR4 and siEGFR could inhibit cells biological activities. In addition, LGR4 overexpression promoted the expression levels of RSPO2, ß-catenin, EGFR and cancer stem cells (CSCs) markers, whereas silence of LGR4 or EGFR could diminish the expression levels of ß-catenin and CSCs markers. Furthermore, knockdown of LGR4 or EGFR also inhibited tumor growth and reduced the expression levels of RSPO2, CD133, CD44, Nanog, ß-catenin in vivo. CONCLUSION: Our data suggest that LGR4 /EGFR signaling in HCC leads to induce tumor growth, which then contributes to stem cell characteristics. It maybe a new perspective for the targeted therapy of HCC treatment.

Daytime and nighttime high temperatures differentially increased the risk of cardiovascular disease: A nationwide hospital-based study in China.

Short-term exposure to ambient high temperature (heat) could increase the risk of cardiovascular disease (CVD). However, available evidence on the burden of daytime and nighttime heat on CVD is limited and vulnerable populations remain unknown so far. We aimed to examine and differentiate the impact of daytime and nighttime heat on CVD in China. Data on daily outpatient visits for CVD were collected from 15 Chinese cities spanning multiple geographical regions, climates, and socio-economic conditions. The population-weighted temperature was used to calculate excess heat exposure in warm seasons (June-September) from 2011 to 2015. Hot day excess (HDE) and hot night excess (HNE), the sum of temperature above the heat threshold during daytime and nighttime respectively, were used to represent daytime and nighttime excess heat. A distributed lag non-linear model was employed to estimate the city-level association between HDE/HNE and daily CVD cases. The city-level association was then pooled by multivariate meta-analysis. We further estimated the disease burden of CVD attributable to HDE and HNE by geographical regions, gender, and age. A total of 729,409 cases of CVD were included in this study. Both HDE and HNE were associated with an increased risk of CVD, with greater effects from nighttime heat (relative risk (RR): 1.38; 95% confidence interval (CI): 1.18-1.61) than daytime heat (RR: 1.10; 95% CI: 1.05-1.15). The proportion of CVD cases attributable to HNE was 15.7%, which was almost three times as high as HDE (4.6%, p for difference <0.05). Males, people living in northern cities, and those aged less than 45 years were more vulnerable to HNE. Our findings for the first time revealed an intra-day difference in the heat effect on CVD, with a greater impact from nighttime heat exposure, which should be considered to protect vulnerable populations on hot days.

Association between health literacy and dysphagia in the community-dwelling older population: a cross-sectional study.

BACKGROUND: Dysphagia, or swallowing disorders, has become a growing concern due to the aging population, and health literacy plays a crucial role in active aging. However, the relationship between them remains unclear. AIMS: To investigate the association between health literacy and dysphagia among community-dwelling older adults in China. METHODS: A survey was conducted on 4462 older adults aged 65 and above in a community in Yiwu City, China, from May 2021 to January 2022. Swallowing problems were assessed using a 30 ml water swallowing test (WST) and the Eating Assessment Tool-10 questionnaire (EAT-10). The participants' health literacy was evaluated using the Chinese Health Literacy Scale (CHLS). Logistic regression and t tests were employed to measure the association between them. RESULTS: The prevalence of dysphagia was 5.70% and 7.85% as determined by EAT-10 and 30 ml-WST, respectively. The health literacy level of community-dwelling older adults was 24.4 ± 4.93 (9-45). Participants with dysphagia exhibited lower levels of health literacy (p < 0.05). The logistic regression model demonstrated an inverse association between health literacy and dysphagia (OR = 0.94, 95%CI = 0.91-0.96 for EAT-10, and OR = 0.93, 95%CI = 0.92-0.95 for WST). Moreover, this association remained significant even after adjusting for covariates. DISCUSSION: Older adults with dysphagia have lower levels of health literacy, particularly in terms of their ability to seek medical advice, acquire and evaluate medical information, and access social support resources. CONCLUSIONS: Health literacy is associated with dysphagia among community-dwelling older adults. Effective interventions should be implemented to provide support in terms of both medical services and social support for this population.

An effectiveness evaluation of a community-based course for medical students: a randomized controlled trial in the teaching of epidemiology.

BACKGROUND: Epidemiology is considered to be the fundamental science of public health and plays an important role in clinical competence and professional development. The objective of this study is to evaluate the effectiveness of a short-term course for the teaching of epidemiology, which was designed as a community-based class for medical students. METHOD: This course was designed according to Kern's six-step approach to curriculum development. A total of 75 undergraduates were recruited. Forty-one students were assigned to an experimental group engaged in theoretical teaching and practical courses, while 34 students were assigned to the control group only taking theoretical courses. All participants were asked to complete a pre- and post-course survey and to take a test after completing the course. The scores between the experimental and control groups were compared using the Wilcoxon test. RESULT: The experimental group showed significantly higher self-assessment scores in course understanding (p = 0.0126) and clinical practice skills (p = 0.0005) after completing the course, while no significant difference was observed in the control group. In addition, students in the experimental group reported significantly higher interest (p = 0.0015), stronger learning motivation (p = 0.0113) and a better mastery of epidemiology (p = 0.0167) after completing the course than those in the control group. However, test scores (p = 0.0859) and pass rates (p = 0.1755) demonstrated no statistical significance between the two groups. CONCLUSION: The short-term practical course in epidemiology exerted significantly positive effects on the improvement of student learning enthusiasm, course understanding and clinical practice skills. These findings provide new ideas and statistical evidence for the development of epidemiological instruction. Future studies should explore how to more widely and optimally apply community-based courses to the teaching of epidemiology.

Application of 3D Slicer Combined With Simple Coordinate Method in Operation of Cerebral Arteriovenous Malformations in Functional Areas.

The authors report a case of intracranial arteriovenous malformation in functional areas, initially presenting with symptomatic epilepsy was surgically excised by the Neurosurgery Department of our hospital. The patient's head computed tomography, magnetic resonance imaging, and digital subtraction angiography examination suggested intracranial arteriovenous malformations in the left frontal functional area. A preoperative 3D-reconstruction technique was used to reconstruct the malformed vascular mass, supplying arteries, draining veins, and precise surgical resection was performed. Postoperative pathology indicated vascular malformation. No seizures occurred after surgery. There was no further neurological impairment. Preoperative use of image postprocessing techniques can facilitate precise surgical resection of brain arteriovenous malformations. Three-dimensional Slicer in cerebral arteriovenous malformations in functional areas not only shortened the preoperative planning time but also improved the efficiency of the surgery. Reduce the incidence of postoperative complications. It is helpful for further popularization and application.

Molecular Planarization of Raman Probes to Avoid Background Interference for High-Precision Intraoperative Imaging of Tumor Micrometastases and Lymph Nodes.

The intraoperative imaging applications of a large number of Raman probes are hampered by the overlap of their signals with the background Raman signals generated by biological tissues. Here, we describe a molecular planarization strategy for adjusting the Raman shift of these Raman probes to avoid interference. Using this strategy, we modify the backbone of thiophene polymer-poly(3-hexylthiophene) (P3HT), and obtain the adjacent thiophene units planarized polycyclopenta[2,1-b;3,4-b']dithiophene (PCPDT). Compared with P3HT whose signal is disturbed by the Raman signal of lipids in tissues, PCPDT exhibits a 60 cm-1 blueshift in its characteristic signal. Therefore, the PCPDT probe successfully avoids the signal of lipids, and achieves intraoperative imaging of lymph nodes and tumor micrometastasis as small as 0.30 × 0.36 mm. In summary, our study presents a concise molecular planarization strategy for regulating the signal shift of Raman probes, and brings a tunable thiophene polymer probe for high-precision intraoperative Raman imaging.

The development and validation of Chinese Health Literacy Scale (CHLS) for older people.

OBJECTIVES: We tried to develop a more concise health literacy scale for Chinese older adults. METHODS: A draft scale based on the Health Literacy Questionnaire (HLQ) was developed, and revised by experts. We conducted a pilot study to test the readability and establish a standard inquiry method within 10 residents. We tested the validity and internal consistency using a field test with 3,739 participants. RESULTS: Overall standardized Cronbach's α of Chinese Health Literacy Scale (CHLS) was 0.86 and that of each dimension ranged from 0.69 to 0.81. Nearly all dimensions had satisfactory factor loadings (0.33-0.98). The correlation coefficient between the score of each item and its dimension ranged from 0.59 to 0.92. CONCLUSIONS: The performance of CHLS was almost the same as the HLQ but more concise. It might play a role in reflecting the health literacy of older adults in China and further promoting their health.

Molecular Regulation of Polymeric Raman Probes for Ultrasensitive Microtumor Diagnosis and Noninvasive Microvessle Imaging.

Raman imaging is a powerful tool for the diagnosis of cancers and visualization of various biological processes. Polymers possessing excellent biocompatibility are promising probes for Raman imaging. However, few polymers are reported to serve as Raman probes for in vivo imaging, mainly due to the intrinsic weak Raman signal intensity and fluorescence interference of these polymers. Herein, a poly(indacenodithiophene-benzothiadiazole) (IDT-BT) polymer is presented, which emits unprecedentedly strong Raman signals under the near-infrared wavelength (785 nm) excitation, thus functioning as a Raman probe for ultrasensitive in vivo Raman imaging. Further mechanistic studies unveil that the unique Raman feature of the IDT-BT polymer relies on molecularly regulating its absorbance edge adjacent to the desired excitation wavelength, thus avoiding fluorescence interference and simultaneously emitting strong Raman scattering under preresonant excitation. Taking advantage of this discipline, the IDT-BT polymeric probe successfully realizes intraoperative Raman imaging of micrometastasis as small as 0.3 mm × 0.3 mm, comparable to the most sensitive Raman probes currently reported. Impressively, the IDT-BT enables noninvasive microvascular imaging, which is not achieved using other Raman probes. This work opens a new avenue toward the development of polymeric Raman probes for in vivo Raman imaging.

Optical properties of soot aggregates with different monomer shapes.

The monomer of soot fractal aggregate is usually considered to be sphere, but the monomer shapes are cube and hexagon by some transmission electron microscope (TEM) and scanning electron microscope (SEM) observation. In this paper, the fractal soot models of different monomer shapes (sphere, cube, ellipsoid, hexagonal prism) were established. And the optical properties of models are calculated by discrete dipole approximation (DDA). After systematically comparing the Muller matrix and optical cross section properties between the models, we find that monomer deviation from sphericity does not necessarily lead to further decline of F22(π)/F11(π) even at shorter wavelengths. In other words, the non-sphericity of monomers does not necessarily affect the non-sphericity of whole soot particle. This can provide some implication for lidar remote sensing observation. However, other light scattering matrix elements can keep good consistency. The maximum deviation of extinction cross section of hexagonal prism model is 11.2%. The more the monomer shape deviates from the sphere, the more the optical integral properties of the non-spherical monomer model deviates from the optical integral properties of sphere monomer model. Hence, the difference in optical properties caused by different monomer shapes cannot be neglected when the monomer deviates significantly from a spherical shape. This work is helpful to evaluate the optical properties of soot aggregates more precisely.

Selective acceleration of 2-hydroxyl pyridine mono-oxygenation using specially acclimated biomass.

Biodegradation of pyridine starts with two mono-oxygenation reactions, and 2-hydroxyl pyridine (2-HP) accumulates as pyridine is mono-oxygenated in the first reaction. The accumulation of 2-HP inhibits both initial reactions. Therefore, selective acceleration of the second mono-oxygenation reaction should significantly enhance pyridine transformation and mineralization. Activated-sludge biomass was separately acclimated with pyridine or 2-HP to produce pyridine- and 2-HP-acclimated biomasses. The pyridine-acclimated biomass was superior for pyridine biodegradation, but the 2-HP-acclimated biomass was superior for 2-HP biodegradation. As a consequence, the pyridine-acclimated biomass by itself achieved faster mono-oxygenation of pyridine to 2-HP, but 2-HP accumulated, which limited mineralization to 60%. In contrast, mineralization reached 90% when one-third of the pyridine-acclimated was replaced with 2-HP-acclimated biomass, because 2-HP did not accumulate during pyridine biodegradation. The lack of 2-HP accumulation relieved its inhibition: e.g., the pyridine removal rates, normalized to the mass of pyridine-acclimated biomass, increased from 0.52 to 0.57 mM0.5⋅h-1 when one-third of the pyridine-acclimated biomass was replaced by 2-HP-acclimated biomass. Phylogenetic analysis showed that microbiological communities of pyridine-acclimated biomass and 2-HP-acclimated biomass differed in important ways. On the one hand, the 2-HP-acclimated biomass was richer and dominated by a rare biosphere, or genera having <0.1% of total reads. On the other hand, the most-enriched genus in the pyridine-acclimated community (Methylibium) is associated with the first mono-oxygenation of pyridine, while enriched genera in the 2-HP-acclimated community (Sediminibacterium and Dokdonella) are associated with the second mono-oxygenation of pyridine.

A Multiple-Stimuli-Responsive Amphiphilic Copolymer for Antifouling and Antibacterial Functionality via a "Resistance-Kill-Release" Mechanism.

In recent years, polymers with stimuli-responsive properties have been increasingly reported on due to their diverse applications. However, most of the studies have only focused on the performance of polymers under specific scenarios. The laws of changes in the properties in response to various external stimuli have been less systematically and quantitatively studied. In this paper, we prepared an amphiphilic polymer (PadaMX and PAdaM3QA-X) with temperature-, pH-, ion-, and ß-cyclodextrin (ß-CD)-responsive properties. According to the cloud point tested by the UV-Vis method, the lower critical soluble temperature (LCST) of PAdaM3QA-10% was more sensitive to a change in pH and less sensitive to a change in ions compared with PadaM3 due to quaternized side chains with a stronger intramolecular mutual repulsion. We then fabricated the coatings with responsive properties by immobilizing the adamantyl groups on ß-CD-modified surfaces. The hydrophilicity of the coatings was improved after quaternization, as proven by the water contact angle (WCA) measurement. The antifouling and antibacterial performance was further evaluated via the fluorescence intensity of bovine serum albumin (BSA) adsorbed on the surfaces and the spread plate method. A 78.4% BSA desorption rate and a 96.8% sterilization rate were achieved by the PAdaM3QA-10% coating. In summary, this work prepared a multiple-stimuli-responsive amphiphilic copolymer for antifouling and antibacterial functionality via a "resistance-kill-release" mechanism.

Optical Properties of New Third-Order Nonlinear Materials Modified by Click Chemistry.

A high-yielding click reaction was used to synthesize a series of highly conjugated, symmetrical, as well as asymmetrical compounds with a benzene core. Cyclic voltammetry and ultraviolet/visible absorption spectroscopy were carried out, and proved that the side groups of the benzene derivatives played an important role in the energy gaps, and affected the third-order non-linear optical response. The maximum absorption wavelength of the series of benzene derivatives showed an obvious red-shift. Moreover, the addition of resilient electron-withdrawing groups significantly narrowed the energy levels as compared with precursors. The third-order nonlinear properties of this benzene derivative were tested by the Z-scan technique. The expected properties of this series of molecules were obtained, and it was found that the series of molecules undergoes a transition from reverse saturable absorption to saturable absorption, which has certain reference significance for a nonlinear optical field.