Metabolic stress induces a double-positive feedback loop between AMPK and SQSTM1/p62 conferring dual activation of AMPK and NFE2L2/NRF2 to synergize antioxidant defense.

Co-occurring mutations in KEAP1 in STK11/LKB1-mutant NSCLC activate NFE2L2/NRF2 to compensate for the loss of STK11-AMPK activity during metabolic adaptation. Characterizing the regulatory crosstalk between the STK11-AMPK and KEAP1-NFE2L2 pathways during metabolic stress is crucial for understanding the implications of co-occurring mutations. Here, we found that metabolic stress increased the expression and phosphorylation of SQSTM1/p62, which is essential for the activation of NFE2L2 and AMPK, synergizing antioxidant defense and tumor growth. The SQSTM1-driven dual activation of NFE2L2 and AMPK was achieved by inducing macroautophagic/autophagic degradation of KEAP1 and facilitating the AXIN-STK11-AMPK complex formation on the lysosomal membrane, respectively. In contrast, the STK11-AMPK activity was also required for metabolic stress-induced expression and phosphorylation of SQSTM1, suggesting a double-positive feedback loop between AMPK and SQSTM1. Mechanistically, SQSTM1 expression was increased by the PPP2/PP2A-dependent dephosphorylation of TFEB and TFE3, which was induced by the lysosomal deacidification caused by low glucose metabolism and AMPK-dependent proton reduction. Furthermore, SQSTM1 phosphorylation was increased by MAP3K7/TAK1, which was activated by ROS and pH-dependent secretion of lysosomal Ca2+. Importantly, phosphorylation of SQSTM1 at S24 and S226 was critical for the activation of AMPK and NFE2L2. Notably, the effects caused by metabolic stress were abrogated by the protons provided by lactic acid. Collectively, our data reveal a novel double-positive feedback loop between AMPK and SQSTM1 leading to the dual activation of AMPK and NFE2L2, potentially explaining why co-occurring mutations in STK11 and KEAP1 happen and providing promising therapeutic strategies for lung cancer.

Improved Charge Injection Balance in Quantum Dot Light-Emitting Diodes through Interface Texture.

The existing methods to improve the charge balance of quantum dot light-emitting diodes (QLEDs) rely on energy-level matching, but these approaches have been limited by material availability and Fermi-level pinning. Here, we propose a solution that does not require changes to the materials' electronic properties. By using nanoimprinting technology to texture the interface between the hole-transporting layer (HTL) and colloidal quantum dot (CQD) layer, we can increase the HTL-CQD contact area. This significantly enhances the hole injection rate while keeping the electron injection rate essentially unchanged. Compared with the conventional planar structure, QLEDs with textured HTL exhibit lower luminance threshold voltage, significantly higher external quantum efficiency at low bias voltages, improved operational stability, and a similar Lambertian factor. Comprehensive measurements confirm that the HTL-CQD interface texture allows more efficient hole injection into CQDs to occur under lower bias, resulting in less CQD charging and more efficient exciton recombination.

Microbial diversity and oil biodegradation potential of northern Barents Sea sediments.

The Arctic, an essential ecosystem on Earth, is subject to pronounced anthropogenic pressures, most notable being the climate change and risks of crude oil pollution. As crucial elements of Arctic environments, benthic microbiomes are involved in climate-relevant biogeochemical cycles and hold the potential to remediate upcoming contamination. Yet, the Arctic benthic microbiomes are among the least explored biomes on the planet. Here we combined geochemical analyses, incubation experiments, and microbial community profiling to detail the biogeography and biodegradation potential of Arctic sedimentary microbiomes in the northern Barents Sea. The results revealed a predominance of bacterial and archaea phyla typically found in the deep marine biosphere, such as Chloroflexi, Atribacteria, and Bathyarcheaota. The topmost benthic communities were spatially structured by sedimentary organic carbon, lacking a clear distinction among geographic regions. With increasing sediment depth, the community structure exhibited stratigraphic variability that could be correlated to redox geochemistry of sediments. The benthic microbiomes harbored multiple taxa capable of oxidizing hydrocarbons using aerobic and anaerobic pathways. Incubation of surface sediments with crude oil led to proliferation of several genera from the so-called rare biosphere. These include Alkalimarinus and Halioglobus, previously unrecognized as hydrocarbon-degrading genera, both harboring the full genetic potential for aerobic alkane oxidation. These findings increase our understanding of the taxonomic inventory and functional potential of unstudied benthic microbiomes in the Arctic.

Relationship between plasma TNF-α levels and agitation symptoms in first episode patients with schizophrenia.

BACKGROUND: Increasing evidence suggested that immune abnormalities involved in the pathophysiology of schizophrenia. However, the relationship between immunity and clinical features has not been clarified. The aim of this study was to measure the plasma levels of tumor necrosis factor alpha (TNF-α) and soluble TNF-α receptor 1 (sTNF-α R1) and to investigate their association with agitation in first episode patients with schizophrenia (FEPS). METHODS: The plasma TNF-α and sTNF-α R1 levels were measured using sandwich enzyme-linked immunosorbent assay (ELISA) in the FEPS with (n = 36) and without agitation (n = 49) symptoms, and healthy controls (HCs, n = 54). The psychopathology was assessed by the Positive and Negative Syndrome Scale (PANSS), and the agitation symptoms were evaluated by the PANSS excitatory component (PANSS-EC). RESULTS: The plasma TNF-α levels in patients with and without agitation symptoms were significantly higher than those in HCs. The patients with agitation had significantly higher plasma TNF-α levels compared to the patients without agitation. There were no significant differences in the sTNF-α R1 levels among the three groups. Furthermore, the plasma TNF-α levels were positively correlated with the PANSS total score, Positive and General psychopathological subscores, and PANSS-EC score in the FEPS, but the relationships were not found for the plasma sTNF-α R1 levels. CONCLUSIONS: These results suggested that TNF-α might play an important role in the onset and development of agitation symptoms of schizophrenia.

Development and evaluation of interpretable machine learning regressors for predicting femoral neck bone mineral density in elderly men using NHANES data.

Osteoporotic femoral neck fractures (OFNFs) pose a significant orthopedic challenge in the elderly population, accounting for up to 40% of all osteoporotic fractures and leading to considerable health deterioration and increased mortality. In addressing the critical need for early identification of osteoporosis through routine screening of femoral neck bone mineral density (FNBMD), this study developed a user-friendly prediction model aimed at men aged 50 years and older, a demographic often overlooked in osteoporosis screening. Utilizing data from the National Health and Nutrition Examination Survey (NHANES), the study involved outlier detection and handling, missing value imputation via the K nearest neighbor (KNN) algorithm, and data normalization and encoding. The dataset was split into training and test sets with a 7:3 ratio, followed by feature screening through the least absolute shrinkage and selection operator (LASSO) and the Boruta algorithm. Eight different machine learning algorithms were then employed to construct predictive models, with their performance evaluated through a comprehensive metric suite. The random forest regressor (RFR) emerged as the most effective model, characterized by key predictors such as age, body mass index (BMI), poverty income ratio (PIR), serum calcium, and race, achieving a coefficient of determination (R²) of 0.218 and maintaining robustness in sensitivity analyses. Notably, excluding race from the model resulted in sustained high performance, underscoring the model's adaptability. Interpretations using Shapley additive explanations (SHAP) highlighted the influence of each feature on FNBMD. These findings indicate that our predictive model effectively aids in the early detection of osteoporosis, potentially reducing the incidence of OFNFs in this high-risk population.

Construction of V2O5@MXene Cathodes toward a High Specific Capacity Aqueous Aluminum-Ion Battery.

Aqueous aluminum-ion batteries (AAIBs) are considered a strong candidate for the new generation of energy storage devices. The lack of suitable cathode materials has been a bottleneck factor hindering the future development of AAIBs. In this work, we design and construct a highly effective cathode with dual morphologies. Two-dimensional (2D) layered MXene materials possessed good conductivity and hydrophilicity, which are used as the substrates to deposit rod-shaped vanadium oxides (V2O5) to form a three-dimensional (3D) cathode. The cathode design provides a strong boost for the rapid electrochemical activities of rod-shaped V2O5 by embedding/extracting both protons (H+) and aluminum-ion (Al3+). As a result, the V2O5@MXene cathode based AAIB delivers an ultrahigh initial specific capacity of 626 mAh/g at 0.1 A/g with a stable cycle performance up to 100 cycles. This work is a breakthrough for the development of cathode materials for AAIBs.

Dynamic regulation of stem cell adhesion and differentiation on degradable piezoelectric poly (L-lactic acid) (PLLA) nanofibers.

Degradable piezoelectric materials possess significant potential for application in the realm of bone tissue regeneration. However, the correlation between cell regulation mechanisms and the dynamic variation caused by material degradation has not been explained, hindering the optimization of material design and its in vivo application. Herein, piezoelectric poly (L-lactic acid) (PLLA) nanofibers with different molecular weights (MW) were fabricated, and the effects of their piezoelectric properties, structural morphology, and material products during degradation on the adhesion and osteogenic differentiation of mesenchymal stem cells (MSCs) were investigated. Our results demonstrated that cell adhesion-mediated piezoelectric stimulation could significantly enhance cell spreading, cell orientation, and upregulate the expression of calmodulin, which further triggers downstream signaling cascade to regulate osteogenic differentiation markers of type I collagen and runt-related transcription factor 2. Additionally, during the degradation of the nanofibers, the piezoelectric properties of PLLA weakened, the fibrous structure gradually diminished, and pH levels in the vicinity decreased, which resulting in reduced osteogenic differentiation capability of MSCs. However, nanofibers with higher MW (280 kDa) have the ability to maintain the fibrous morphology and piezoelectricity for a longer time, which can regulate the osteogenic differentiation of stem cells for more than 4 weeks. These findings have provide a new insight to correlate cell behavior with MW and the biodegradability of piezopolymers, which revealed an active method for cell regulation through material optimization for bone tissue engineering in near future.

Factors associated with dysmenorrhoea and menorrhagia improvement in patients with adenomyosis after uterine artery embolisation.

BACKGROUND: This study examined the improvement of dysmenorrhoea and menorrhagia after uterine artery embolisation (UAE) in women with symptomatic adenomyosis and identified factors that could predict the improvement of dysmenorrhoea and menorrhagia. METHODS: This retrospective study included women with adenomyosis who underwent bilateral UAE between December 2014 and December 2016. The percentage of the volume of the absence of contrast enhancement on T1-weighted images was evaluated 5-7 days after UAE. A receiver operating characteristic (ROC) analysis was used to determine a cut-off point and predict the improvement of dysmenorrhoea and menorrhagia. RESULTS: Forty-eight patients were included. At 24 and 36 months after UAE, the improvement rates for dysmenorrhoea and menorrhagia were 60.4% (29/48) and 85.7% (30/35), and the recurrence rates were 19.4% (7/36) and 9.1% (3/33), respectively. Only the percentage of the volume of the absence of contrast enhancement on T1-weighted images was associated with the improvement of dysmenorrhoea (p = 0.001, OR = 1.051; 95% CI: 1.02-1.08) and menorrhagia (p = 0.006, OR = 1.077; 95% CI: 1.021-1.136). When the cut-off value of the ROC analysis was 73.1%, sensitivity, specificity, positive predictive value, and negative predictive value for the improvement of dysmenorrhoea were 58.6%, 94.7%, 94.4%, and 60%, while they were 58.9%, 80%, 100%, 100%, and 45.5% for the improvement of dysmenorrhoea. CONCLUSION: Bilateral UAE for symptomatic adenomyosis led to good improvement of dysmenorrhoea and menorrhagia. The percentage of the volume of the absence of contrast enhancement on T1-weighted images of the uterus in postoperative magnetic resonance imaging might be associated with the improvement of dysmenorrhoea and menorrhagia.

This study examined the improvement of dysmenorrhoea and menorrhagia after uterine artery embolisation in women with symptomatic adenomyosis and identified factors that could predict the improvement of dysmenorrhoea and menorrhagia. This retrospective study included women with adenomyosis who underwent uterine artery embolisation. A total of 48 patients were included. Only the percentage of the volume of the absence of contrast enhancement on T1-weighted images was associated with improvement of dysmenorrhoea and menorrhagia. Bilateral uterine artery embolisation for symptomatic adenomyosis led to good improvement. The percentage of the volume of the absence of contrast enhancement on images in postoperative T1-weighted magnetic resonance imaging of the uterus might be associated with the improvement of dysmenorrhoea and menorrhagia.

Serum proteomics study on cognitive impairment after cardiac valve replacement surgery: a prospective observational study.

Objective: The incidence of perioperative neurocognitive disorders (PND) is high, especially after cardiac surgeries, and the underlying mechanisms remain elusive. Here, we conducted a prospective observational study to observe serum proteomics differences in PND patients after cardiac valve replacement surgery. Methods: Two hundred and twenty-six patients who underwent cardiac valve surgery were included. They were categorized based on scoring into non-PND group (group non-P) and PND group (group P'). The risk factors associated with PND were analyzed. These patients were further divided into group C and group P by propensity score matching (PSM) to investigate the serum proteome related to the PND by serum proteomics. Results: The postoperative 6-week incidence of PND was 16.8%. Risk factors for PND include age, chronic illness, sufentanil dosage, and time of cardiopulmonary bypass (CPB). Proteomics identified 31 down-regulated proteins and six up-regulated proteins. Finally, GSTO1, IDH1, CAT, and PFN1 were found to be associated with PND. Conclusion: The occurrence of PND can impact some oxidative stress proteins. This study provided data for future studies about PND to general anaesthesia and surgeries.

Rapid-response near-infrared fluorescence probe for colorimetric detection of HClO and its applications in environmental monitoring and biological imaging.

As a crucial endogenous reactive oxygen species, hypochlorous acid (HClO) plays an indispensable role in numerous physiological and pathological processes. Additionally, it serves as a biomarker closely associated with inflammation and liver injury. The utilization of near-infrared fluorescence probes has surged in recent years for live biological imaging, owing to their minimal tissue damage and potent tissue penetration capabilities. In this work, a novel near-infrared fluorescence probe MB-HPD was synthesized to sensitively detect HClO. Probe MB-HPD exhibits remarkable selectivity, high sensitivity (14.3 nM), and rapid response towards HClO (20 s). Probe MB-HPD has demonstrated successful application in the imaging of HClO within cells and zebrafish. Remarkably, it has proven to be effective for detecting HClO within environmental samples, as well as imaging HClO in mice models of arthritis and APAP-induced liver injury. These findings indicate the broad applicability of probe MB-HPD, offering a promising avenue for designing highly selective near-infrared fluorescence probes suitable for real-time HClO monitoring.

History of suicidal behavior and clozapine prescribing among people with schizophrenia in China: a cohort study.

BACKGROUND: Clozapine is an off-label drug used in most countries to prevent suicide in individuals with schizophrenia. However, few studies have reported real-world prescription practices. This study aimed to explore the association between a history of suicidal behavior and clozapine prescribing during eight weeks of hospitalization for individuals with early-stage schizophrenia. METHODS: This observational cohort study used routine health data collected from a mental health hospital in Beijing, China. The study included 1057 inpatients who had schizophrenia onset within 3 years. History of suicidal behavior was coded from reviewing medical notes according to the Columbia Suicide Severity Rating Scale. Information on antipsychotic use during hospitalization was extracted from the prescription records. Time to clozapine use was analyzed using Cox regression models adjusted for sociodemographic and clinical covariates. RESULTS: The prevalence rates of self-harm, suicidal behavior, and suicide attempt were 12.3%, 7.5%, and 5.4%, respectively. A history of self-harm history was positively associated with clozapine uses upon admission (4.1% vs. 0.8%, exact p = 0.009). Among those who had not used clozapine and had no clozapine contraindication, A history of suicidal behavior increased the possibility of switch to clozapine within 56 days after admission (Hazard Ratio[95% CI], 6.09[2.08-17.83]) or during hospitalization (4.18[1.62-10.78]). CONCLUSION: The use of clozapine for early-stage schizophrenia was more frequent among those with suicidal behavior than among those without suicidal behavior in China, although the drug instructions do not label its use for suicide risk.

Blockage of TMEM189 induces G2/M arrest and inhibits the growth of breast tumors.

Cancer is the major cause of premature death in humans worldwide, demanding more efficient therapeutics. Aberrant cell proliferation resulting from the loss of cell cycle regulation is the major hallmark of cancer, so targeting cell cycle is a promising strategy to combat cancer. However, the molecular mechanism underlying the dysregulation of cell cycle of cancer cells remains poorly understood. TMEM189, a newly identified protein, plays roles in the biosynthesis of ethanolamine plasmalogen and the regulation of autophagy. Here, we demonstrated that the expression level of TMEM189 was negatively correlated with the survival rate of the cancer patients. TMEM189 deficiency significantly suppresses the cancer cell proliferation and migration, and causes cell cycle G2/M arrest both in vitro and in vivo. Furthermore, TMEM189 depletion suppressed the growth of breast tumors in vivo. Taken together, our work indicated that TMEM189 promotes cancer progression by regulating cell cycle G2/M transition, suggesting that it is a promising target in cancer therapy.

Neoadjuvant sintilimab plus chemotherapy in EGFR-mutant NSCLC: Phase 2 trial interim results (NEOTIDE/CTONG2104).

The clinical efficacy of neoadjuvant immunotherapy plus chemotherapy remains elusive in localized epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC). Here, we report interim results of a Simon's two-stage design, phase 2 trial using neoadjuvant sintilimab with carboplatin and nab-paclitaxel in resectable EGFR-mutant NSCLC. All 18 patients undergo radical surgery, with one patient experiencing surgery delay. Fourteen patients exhibit confirmed radiological response, with 44% achieving major pathological response (MPR) and no pathological complete response (pCR). Similar genomic alterations are observed before and after treatment without influencing the efficacy of subsequent EGFR-tyrosine kinase inhibitors (TKIs) in vitro. Infiltration and T cell receptor (TCR) clonal expansion of CCR8+ regulatory T (Treg)hi/CXCL13+ exhausted T (Tex)lo cells define a subtype of EGFR-mutant NSCLC highly resistant to immunotherapy, with the phenotype potentially serving as a promising signature to predict immunotherapy efficacy. Informed circulating tumor DNA (ctDNA) detection in EGFR-mutant NSCLC could help identify patients nonresponsive to neoadjuvant immunochemotherapy. These findings provide supportive data for the utilization of neoadjuvant immunochemotherapy and insight into immune resistance in EGFR-mutant NSCLC.

The tumour suppressor Fat1 is dispensable for normal murine hematopoiesis.

Loss and overexpression of FAT1 occurs among different cancers with these divergent states equated with tumor suppressor and oncogene activity, respectively. Regarding the latter, FAT1 is highly expressed in a high proportion of human acute leukemias relative to normal blood cells, with evidence pointing to an oncogenic role. We hypothesized that this occurrence represents legacy expression of FAT1 in undefined hematopoietic precursor subsets that is sustained following transformation, predicating a role for FAT1 during normal hematopoiesis. We explored this concept by using the Vav-iCre strain to construct conditional knockout (cKO) mice where Fat1 expression was deleted at the hematopoietic stem cell stage. Extensive analysis of precursor and mature blood populations using multi-panel flow cytometry revealed no ostensible differences between Fat1 cKO mice and normal littermates. Further functional comparisons involving colony forming unit and competitive bone marrow transplantation assays support the conclusion that Fat1 is dispensable for normal murine hematopoiesis.

Mechanism of PTPN18 for regulating the migration and invasion of endometrial cancer cells via the MYC/PI3K/AKT pathway.

OBJECTIVE: Endometrial cancer (EC) is a prevalent gynecologic malignancy. The critical role of PTPN18 in EC has been reported, while its role in the aerobic glycolysis of EC cells remains unclear. Our current study focused on the mechanism of PTPN18 in the regulation of aerobic glycolysis in EC. METHODS: PTPN18 expression levels in endometrial stromal cells (KC02-44D) and EC cells (KLE, HEC-1-A, HEC-1B, and HEC-50) were determined. Following transfection of sh-PTPN18 in HEC-1-A cells, the changes in cell migratory and invasive abilities were assessed by the Transwell assay, and the changes in glucose consumption, lactic acid secretion, and ATP levels were detected using kits. The expression levels of glycolysis-related proteins HIF-1α, PKM2, and LDHA and the activation of the MYC/PI3K/AKT pathway were detected by Western blot. Additionally, sh-PTPN18 and pcDNA3.1-MYC were transfected into HEC-1-A cells to further explore their roles in the changes in aerobic glycolysis, migration, and invasion ability of EC cells. RESULTS: Expression of PTPN18 in EC cells was up-regulated (HEC-1-A>HEC-1B>HEC-50>KLE). PTPN18 knockdown suppressed EC cell migration and invasion. Additionally, PTPN18 knockdown reduced glucose consumption, lactate production, ATP levels, and glycolysis-related protein levels (HIF-1α, PKM2, LDHA). PTPN18 knockdown inhibited the activation of the MYC/PI3K/AKT pathway in EC cells. MYC overexpression partially annulled the inhibitory effects of PTPN18 knockdown on aerobic glycolysis, migration, and invasion of EC cells. CONCLUSION: Our present study provided evidence that the knockdown of PTPN18 inhibited the aerobic glycolysis, migration, and invasion of EC cells by suppressing the MYC/PI3K/AKT pathway.

Stability-enhanced low-frequency fiber optic hydrophone based on an extrinsic Fabry-Perot interferometer.

Fiber optic hydrophones (FOHs) offer the notable advantage of electromagnetic interference resistance. Nevertheless, overcoming the challenge of sustaining stable, high-performance operation in intricate underwater settings at a low cost remains a considerable obstacle for them. To circumvent the restrictions noted above, we employed a miniaturized FOH, utilizing an easily fabricated extrinsic Fabry-Perot interferometer (EFPI) which is made up of a composite chromium-aluminum (Cr-Al) membrane and fiber. The linear demodulation also suppresses the drift issue in the output spectrum. The average sound pressure sensitivity of the sensor, according to experimental findings, is around -139.15 dB re 1 V/µPa, while the equivalent noise sound pressure at 1 kHz is 51.52 dB re 1 µPa/Hz1/2. This sensor has a lot of potential because of features like sensitive low-frequency response and noise performance.

AMPK targets PDZD8 to trigger carbon source shift from glucose to glutamine.

The shift of carbon utilization from primarily glucose to other nutrients is a fundamental metabolic adaptation to cope with decreased blood glucose levels and the consequent decline in glucose oxidation. AMP-activated protein kinase (AMPK) plays crucial roles in this metabolic adaptation. However, the underlying mechanism is not fully understood. Here, we show that PDZ domain containing 8 (PDZD8), which we identify as a new substrate of AMPK activated in low glucose, is required for the low glucose-promoted glutaminolysis. AMPK phosphorylates PDZD8 at threonine 527 (T527) and promotes the interaction of PDZD8 with and activation of glutaminase 1 (GLS1), a rate-limiting enzyme of glutaminolysis. In vivo, the AMPK-PDZD8-GLS1 axis is required for the enhancement of glutaminolysis as tested in the skeletal muscle tissues, which occurs earlier than the increase in fatty acid utilization during fasting. The enhanced glutaminolysis is also observed in macrophages in low glucose or under acute lipopolysaccharide (LPS) treatment. Consistent with a requirement of heightened glutaminolysis, the PDZD8-T527A mutation dampens the secretion of pro-inflammatory cytokines in macrophages in mice treated with LPS. Together, we have revealed an AMPK-PDZD8-GLS1 axis that promotes glutaminolysis ahead of increased fatty acid utilization under glucose shortage.

Ultrabright and stable top-emitting quantum-dot light-emitting diodes with negligible angular color shift.

Top emission can enhance luminance, color purity, and panel-manufacturing compatibility for emissive displays. Still, top-emitting quantum-dot light-emitting diodes (QLEDs) suffer from poor stability, low light outcoupling, and non-negligible viewing-angle dependence because, for QLEDs with non-red emission, the electrically optimum device structure is incompatible with single-mode optical microcavity. Here, we demonstrate that by improving the way of determining reflection penetration depths and creating refractive-index-lowering processes, the issues faced by green QLEDs can be overcome. This leads to advanced device performance, including a luminance exceeding 1.6 million nits, a current efficiency of 204.2 cd A-1, and a T95 operational lifetime of 15,600 hours at 1000 nits. Meanwhile, our design does not compromise light outcoupling as it offers an external quantum efficiency of 29.2% without implementing light extraction methods. Lastly, an angular color shift of Δu'v' = 0.0052 from 0° to 60° is achieved by narrowing the emission linewidth of quantum dots.

Analysis of Alterations in Intestinal Flora in Chinese Elderly with Cardiovascular Disease and Its Association with Trimethylamine.

To investigate the changes in the intestinal flora in the Chinese elderly with cardiovascular disease (CVD) and its correlation with the metabolism of trimethylamine (TMA), the intestinal flora composition of elderly individuals with CVD and healthy elderly individuals was analyzed using 16S rRNA sequencing, the TMA levels in the feces of elderly were detected using headspace-gas chromatography (HS-GC), and four kinds of characterized TMA-producing intestinal bacteria in the elderly were quantified using real-time fluorescence quantitative polymerase chain reaction (qPCR). The results showed that Firmicutes, Actinobacteria, Proteobacteria, Bacteroidetes, and Verrucomicrobia are the dominant microorganisms of the intestinal flora in the Chinese elderly. And there were significant differences in the intestinal bacteria composition between healthy elderly individuals and those with CVD, accompanied by a notable difference in the TMA content. The richness and diversity of the intestinal flora in the elderly with CVD were higher than those in the healthy elderly. Correlation analysis indicated that certain significantly different intestinal flora were associated with the TMA levels. Our findings showed a significant difference in TMA-producing intestinal flora between healthy elderly individuals and those with CVD. The TMA levels were found to be positively and significantly correlated with Klebsiella pneumoniae, suggesting that this bacterium is closely linked to the production of TMA in the elderly gut. This may have implications for the development and progression of CVD in the elderly population.

Near-Infrared Spontaneously Blinking Fluorophores for Live Cell Super-Resolution Imaging with Minimized Phototoxicity.

Single-molecule localization microscopy (SMLM) requires high-intensity laser irradiation, typically exceeding kW/cm2, to yield a sufficient photon count. However, this intense visible light exposure incurs substantial cellular toxicity, hindering its use in living cells. Here, we developed a class of near-infrared (NIR) spontaneously blinking fluorophores for SMLM. These NIR fluorophores are a combination of rhodamine spirolactams and merocyanine derivatives, where the rhodamine spirolactam component converts between a bright and dark state based on pH-dependent spirocyclization and merocyanine derivatives shift the excitation wavelength into the infrared. Single-molecule characterizations demonstrated their potential for SMLM. At a moderate power density of 3.93 kW/cm2, these probes exhibit duty cycle as low as 0.18% and an emission rate as high as 26,700 photons/s. Phototoxicity assessment under single-molecule imaging conditions reveals that NIR illumination (721 nm) minimizes harm to living cells. Employing these NIR fluorophores, we successfully captured time-lapse super-resolution tracking of mitochondria at a Fourier ring correlation (FRC) resolution of 69.4 nm and reconstructed the ultrastructures of endoplasmic reticulum (ER) in living cells.