Greenhouse gas emissions of sewage sludge land application in urban green space: A field experiment in a Bermuda grassland

Sewage sludge land application is recognized as a strategy for recycling resource and replenishing soil nutrients. However, the subsequent greenhouse gas emissions following this practice are not yet fully understood, and the lack of quantitative research and field experiments monitoring these emissions hampers the establishment of reliable emission factors. This study investigated the greenhouse gas emission characteristics of sewage sludge land application through a field experiment that monitoring soil greenhouse gas fluxes. Seven nitrogen input treatments were implemented in a typical Bermuda grassland in China, with D and C representing the amendment of digested and composted sludge, respectively, at the nitrogen input rate of 0, 100, 200, and 300 kg N ha-1. Soil CH4, CO2, and N2O fluxes were measured throughout the entire experimental period, and soil samples from different treatments at various growth stages were analyzed. The results revealed that sewage sludge land application significantly increased soil N2O and CO2 emissions while slightly reducing soil CH4 uptake. The increased CO2 emissions were biogenic and carbon-neutral, mainly due to enhanced plant root respiration. The N2O emissions were the primary greenhouse gas emissions of sewage sludge land application, which were mainly concentrated in two 50-day periods following base and topdressing fertilization, respectively. N2O emissions following base fertilization by rotary tillage were substantially lower than those following topdressing fertilization. A logarithmic response relationship between N input rates and increased soil N2O emissions was observed, suggesting lower N2O emissions from sewage sludge land application compared to conventional N fertilizers at the same N input level. Future field experiments and meta-analysis are necessary to develop reliable greenhouse gas emission factors for sewage sludge land application.

Room-temperature quantum emission from interface excitons in mixed-dimensional heterostructures

The development of van der Waals heterostructures has introduced unconventional phenomena that emerge at atomically precise interfaces. For example, interlayer excitons in two-dimensional transition metal dichalcogenides show intriguing optical properties at low temperatures. Here we report on room-temperature observation of interface excitons in mixed-dimensional heterostructures consisting of two-dimensional tungsten diselenide and one-dimensional carbon nanotubes. Bright emission peaks originating from the interface are identified, spanning a broad energy range within the telecommunication wavelengths. The effect of band alignment is investigated by systematically varying the nanotube bandgap, and we assign the new peaks to interface excitons as they only appear in type-II heterostructures. Room-temperature localization of low-energy interface excitons is indicated by extended lifetimes as well as small excitation saturation powers, and photon correlation measurements confirm antibunching. With mixed-dimensional van der Waals heterostructures where band alignment can be engineered, new opportunities for quantum photonics are envisioned.

Perspectives: Light Control of Magnetism and Device Development

Accurately controlling magnetic and spin states presents a significant challenge in spintronics, especially as demands for higher data storage density and increased processing speeds grow. Approaches such as light control are gradually supplanting traditional magnetic field methods. Traditionally, the modulation of magnetism was predominantly achieved through polarized light with the help of ultrafast light technologies. With the growing demand for energy efficiency and multifunctionality in spintronic devices, integrating photovoltaic materials into magnetoelectric systems has introduced more physical effects. This development suggests that sunlight will play an increasingly pivotal role in manipulating spin orientation in the future. This review introduces and concludes the influence of various light types on magnetism, exploring mechanisms such as magneto-optical (MO) effects, light-induced magnetic phase transitions, and spin photovoltaic effects. This review briefly summarizes recent advancements in the light control of magnetism, especially sunlight, and their potential applications, providing an optimistic perspective on future research directions in this area.

Land use, stratified wastewater and sediment, and microplastic attribute factors jointly influence the microplastic prevalence and bacterial colonization patterns in sewer habitats

The capacity of microplastics to harbor and propagate bacteria has been the focus of attention over the last decade. Such microplastic-supported bacterial colonization behavior in the municipal sewer system could be a critical ecological link influencing the biogeochemical activities and risks in receiving waters in urban areas, given the alarming microplastic loads discharged there. This study conducted a large-scale survey covering a wide range of residential and industrial catchments in Shanghai, China. We aimed to assess the microplastic prevalence and bacterial colonization patterns in different sewer habitats and to explore the role of land use, stratified wastewater and sediment, and microplastic attributes in shaping the patterns. We found that the sewer system formed a temporal but pronounced microplastic pool, with land use playing a significant role in the variability of microplastic prevalence. Industrial sewers contained a high abundance of microplastics with large particle sizes, diverse polymer compositions, and shapes. However, while there was a spatial discrepancy between urban and suburban areas in the abundance of microplastics in residential sewers, their predominant polymer and shape types were simple, i.e., polyethylene terephthalate (PET) and fibers. Sewer habitat characteristics, particularly the stratified wastewater and sediment determined microbial colonization patterns. The latter acted as a long-term sink for microplastics and supported the high growth of colonizers. In contrast, the wastewater plastisphere presented novel niches, hosting communities with a marked proportion of unique bacterial genera after colonization. Besides, statistics showed a highly positive and dense co-occurrence network of the plastisphere communities, especially those from the industrial sewer sediment, with enhanced metabolic activity, cellular processes and systems, and increased human pathogenic potential. Findings indicated a coarse and uncertain effect of the selective pressure of microplastic attributes on plastisphere community structure differentiation.

Deep Learning-Assisted Automated Multidimensional Single Particle Tracking in Living Cells

The translational and rotational dynamics of anisotropic optical nanoprobes revealed in single particle tracking (SPT) experiments offer molecular-level information about cellular activities. Here, we report an automated high-speed multidimensional SPT system integrated with a deep learning algorithm for tracking the 3D orientation of anisotropic gold nanoparticle probes in living cells with high localization precision (<10 nm) and temporal resolution (0.9 ms), overcoming the limitations of rotational tracking under low signal-to-noise ratio (S/N) conditions. This method can resolve the azimuth (0°-360°) and polar angles (0°-90°) with errors of less than 2° on the experimental and simulated data under S/N of ∼4. Even when the S/N approaches the limit of 1, this method still maintains better robustness and noise resistance than the conventional pattern matching methods. The usefulness of this multidimensional SPT system has been demonstrated with a study of the motions of cargos transported along the microtubules within living cells.

Ibrutinib-induced pulmonary angiotensin-converting enzyme activation promotes atrial fibrillation in rats

The molecular mechanism of ibrutinib-induced atrial fibrillation (AF) remains unclear. We here demonstrate that treating rats with ibrutinib for 4 weeks resulted in the development of inducible AF, left atrial enlargement, atrial fibrosis, and downregulation of connexin expression, which were associated with C-terminal Src kinase (CSK) inhibition and Src activation. Ibrutinib upregulated angiotensin-converting enzyme (ACE) protein expression in human pulmonary microvascular endothelial cells (HPMECs) by inhibiting the PI3K-AKT pathway, subsequently increasing circulating angiotensin II (Ang II) levels. However, the expression of ACE and Ang II in the left atria was not affected. Importantly, we observed that perindopril significantly mitigated ibrutinib-induced left atrial remodeling and AF promotion by inhibiting the activation of the ACE and its downstream CSK-Src signaling pathway. These findings indicate that the Ibrutinib-induced activation of the ACE contributes to AF development and could serve as a novel target for potential prevention strategies.

Reaction-Initiated Single-Molecule Tracking of Mass Transfer in Core-Shell Mesoporous Silica Particles

Understanding the host-guest interactions in porous materials is of great importance in the field of separation science. Probing it at the single-molecule level uncovers the inter- and intraparticle inhomogeneity and establishes structure-property relationships for guiding the design of porous materials for better separation performance. In this work, we investigated the dynamics of host-guest interactions in core-shell mesoporous silica particles under in situ conditions by using a fluorogenic reaction-initiated single-molecule tracking (riSMT) approach. Taking advantage of the low fluorescence background, three-dimensional (3D) tracking of the dynamics of the molecules inside the mesoporous silica pore was achieved with high spatial precision. Compared to the commonly used two-dimensional (2D) tracking method, the 3D tracking results show that the diffusion coefficients of the molecules are three times larger on average. Using riSMT, we quantitatively analyzed the mass transfer of probe molecules in the mesoporous silica pore, including the fraction of adsorption versus diffusion, diffusion coefficients, and residence time. Large interparticle inhomogeneity was revealed and is expected to contribute to the peak broadening for separation application at the ensemble level. We further investigated the impact of electrostatic interaction on the mass transfer of molecules in the mesoporous silica pore and discovered that the primary effect is on the fraction rather than their diffusion rates of resorufin molecules undergoing diffusion.

Methionine-CBS axis promotes intracellular ROS levels by reprogramming serine metabolism

As a non-essential amino acid, cysteine could be obtained through both exogenous uptake and endogenous de novo synthesis pathways. Research has demonstrated that restricting the uptake of cystine could result in a depletion of intracellular cysteine and glutathione, ultimately leading to an increase in intracellular reactive oxygen species (ROS) levels. However, the role of methionine in regulating intracellular ROS levels is currently unclear. Here, we want to explore the role of methionine in regulating intracellular ROS levels. We found that methionine restriction could lead to a decrease in intracellular ROS levels, while supplementation with SAM can restore these levels through flow cytometry. Mechanically, we found that the methionine-SAM axis relies on CBS when regulating intracellular ROS levels. Furthermore, we speculate and prove that the methionine-SAM-CBS axis alters the metabolism of serine, thereby reducing intracellular reductive power, therefore promoting intracellular ROS levels through changing metabolite levels and genetic methods. Finally, our study revealed that high expression of CBS in tumor cells could lead to increased intracellular ROS levels, ultimately resulting in faster proliferation rates. Together, our study confirmed that methionine plays a promoting role in the regulation of intracellular ROS levels.

Contrast-enhanced Ultrasonography for Diagnosis of Small Intestinal Leiomyosarcoma with Hepatic Metastasis: A Clinical Report of One Case and Review of the Literature

BACKGROUND

Small intestinal leiomyosarcoma is a rare malignant tumor of the gastrointestinal tract. Clinical symptoms are atypical and can be complicated by gastrointestinal bleeding and intestinal obstruction.

CASE PRESENTATION

We report a case of a 73-year-old patient with small intestinal smooth muscle sarcoma with hepatic metastasis. No significant abnormalities were seen on examination of the abdomen. We performed abdominal enhancement CT, contrast-enhanced ultrasonography (CEUS), and ultrasoundguided pelvic mass puncture biopsy, and we found a heterogeneous density and echogenicity of the pelvic mass, and the enhancement was progressive with sustained hyperenhancement. The postoperative pathology was smooth muscle sarcoma of the small intestine. The typical fast-in, fast-out bull's-eye sign of metastases, characterized the liver presented with multiple hypodense and echogenic nodules and the enhancement. The clinical presentation, imaging, histologic features, and treatment are also discussed in this article.

CONCLUSION

This article briefly reviews the literature on small intestinal leiomyosarcoma. The purpose of this case report is to emphasize the specificity of the case and evaluate the imaging presentation of ultrasound (US) and CEUS and the main differential diagnosis of this rare gastrointestinal tumor.

Coordinates in low-dimensional cell shape-space discriminate migration dynamics from single static cell images

Cell shape has long been used to discern cell phenotypes and states, but the underlying premise has not been quantitatively tested. Here, we show that a single cell image can be used to discriminate its migration behavior by analyzing a large number of cell migration data in vitro. We analyzed a large number of two-dimensional cell migration images over time and found that the cell shape variation space has only six dimensions, and migration behavior can be determined by the coordinates of a single cell image in this 6-dimensional shape-space. We further show that this is possible because persistent cell migration is characterized by spatial-temporally coordinated protrusion and contraction, and a distribution signature in the shape-space. Our findings provide a quantitative underpinning for using cell morphology to differentiate cell dynamical behavior.

In situ imaging of signaling molecule carbon monoxide in plants with a fluorescent probe

Carbon monoxide (CO) is a recently discovered gasotransmitter. In animals, it has been found that endogenously produced CO participates in the regulation of various metabolic processes. Recent research has indicated that CO, acting as a signaling molecule, plays a crucial regulatory role in plant development and their response to abiotic stress. In this work, we developed a fluorescent probe, named COP (carbonic oxide Probe), for the in situ imaging of CO in Arabidopsis thaliana plant tissues. The probe was designed by combining malononitrile-naphthalene as the fluorophore and a typical palladium-mediated reaction mechanism. When reacted with the released CO, COP showed an obvious fluorescence enhancement at 575 nm, which could be observed in naked-eye conditions. With a linear range of 0-10 μM, the limit of detection of COP was determined as 0.38 μM. The detection system based on COP indicated several advantages including relatively rapid response within 20 min, steadiness in a wide pH range of 5.0-10.0, high selectivity, and applicative anti-interference. Moreover, with a penetration depth of 30 μm, COP enabled 3D imaging of CO dynamics in plant samples, whether it was caused by agent release, heavy metal stress, or inner oxidation. This work provides a fluorescent probe for monitoring CO levels in plant samples, and it expands the application field of CO-detection technology, assisting researchers in understanding the dynamic changes in plant physiological processes, making it an important tool for studying plant physiology and biological processes.

Single Exosome Amperometric Measurements Reveal Encapsulation of Chemical Messengers for Intercellular Communication

In multicellular organisms, cells typically communicate by sending and receiving chemical signals. Chemical messengers involved in the exocytosis of neuroendocrine cells or neurons are generally assumed to only originate from the fusing of intracellular large dense core vesicles (LDCVs) or synaptic vesicles with the cellular membrane following stimulation. Accumulated evidence suggests that exosomes─one of the main extracellular vesicles (EVs)─carrying cell-dependent DNA, mRNA, proteins, etc., play an essential role in cellular communication. Due to experimental limitations, it has been difficult to monitor the real-time release of individual exosomes; this restricts a comprehensive understanding of the basic molecular mechanisms and the functions of exosomes. In this work, we introduce amperometry with microelectrodes to capture the dynamic release of single exosomes from a single living cell, distinguish them from other EVs, and differentiate the molecules inside exosomes and those secreted from LDCVs. We show that, similar to many LDCVs and synaptic vesicles, exosomes released by neuroendocrine cells also contain catecholamine transmitters. This finding reveals a different mode of chemical communication via exosome-encapsulated chemical messengers and a potential interconnection between the two release pathways, changing the canonical view of exocytosis of neuroendocrine cells and possibly neurons. This defines a new mechanism for chemical communication at the fundamental level and opens new avenues in the research of the molecular biology of exosomes in the neuroendocrine and central nervous systems.

The efficacy and mechanism of vonoprazan-containing triple therapy in the eradication of Helicobacter pylori

Purpose: Vonoprazan (VPZ) produces a strong acid-inhibitory effect, which can potentially eradicate Helicobacter Pylori (H. pylori). We aimed to assess whether a 14-day VPZ-containing triple therapy was safe and effective in the Chinese population and the potential mechanism. Methods: Enrolled patients confirmed to be infected with H. pylori were randomly divided into four groups: VPZ + doxycycline + furazolidone, VPZ + doxycycline + amoxicillin, esomeprazole (EPZ) + bismuth + doxycycline + furazolidone, and EPZ + colloidal bismuth + doxycycline + amoxicillin for 14 days. The eradication rate, medication adherence, and incidence of adverse events (AEs) were evaluated. Inhibition of H. pylori by VPZ and EPZ in vitro was assessed. H. pylori treated with appropriate concentrations of VPZ and EPZ were sequenced by transcriptome analysis to explore the antibacterial mechanism. Results: A higher eradication rate were observed in VPZ-containing triple therapy. No obvious differences were observed in medication adherence or the incidence of AEs. VPZ had no direct inhibitory effect on H. pylori, whereas EPZ directly inhibited H. pylori may through downregulated genes related to the ribosome. Conclusion: In the Chinese population, 14-day VPZ-containing triple therapy was safe and more effective and can be used clinically as first-line H. pylori treatment. Clinical Trial Registration: ClinicalTrials.gov, identifier NCT05097846.

Life cycle assessment of greenhouse gas emissions of typical sewage sludge incineration treatment route based on two case studies in China

The rapidly increasing amount of municipal sewage sludge generated in China necessitates a thorough examination and evaluation of available treatment options. In recent years, thermal-drying and incineration technology has gained popularity, however, it may lead to significant greenhouse gas (GHG) emissions. Nevertheless, the differences in boundary conditions and technological characteristic across various cases may affect emission levels significantly. Therefore, this study utilizes a life cycle assessment to estimate the GHG emissions associated with two typical sludge incineration routes in China: direct thermal-drying combined with coal co-incineration incinerator in Case 1 and indirect thermal-drying and self-sustain combustion in Case 2. The entire treatment processes, containing different functional units, were comprehensively investigated. The results demonstrate that Case 1 and Case 2 produce 1133.33 and 350.89 kg CO₂-eq/tDS (sludge dry solid) of GHG emissions, respectively. In Case 1, coal co-incineration produces 828.63 kg CO₂-eq/tDS of GHG emissions, accounting for 73.1% of the total GHG emissions. Moreover, the exhaust gas treatment is a significant GHG emission source, accounting for 9.2% and 16.9% of the total GHG emissions in Case 1 and Case 2, respectively. Additionally, the sludge thickening and dewatering unit in Case 2 produces 213.75 kg CO₂-eq/tDS of GHG emissions, accounting for 60.9% of the total GHG emissions. Analysis of energy flow and heat balance characteristics indicate that the indirect heat transfer method used in thermal-drying leads to significant heat loss, which limits heat recovery potential and hinders GHG emission reduction. This study proposed a scenario case based on Case 2, addressing the issues with the improvement of heat transfer process and reduction of electricity consumption, potentially reducing GHG emissions by 8.8%. Additionally, applying an exhaust gas heat recovery system could further offset up to 22.8% of the total GHG emission.

Insights into multisource sludge distributed in the Yangtze River basin, China: Characteristics, correlation, treatment and disposal

Sludge is the by-product of wastewater treatment process. Multisource sludge can be defined as sludge from different sources. Based on the sludge properties of five typical cities in the Yangtze River basin, including Jiujiang, Wuhu, Lu'an, Zhenjiang and Wuhan, this study investigated and summarized the characteristic variations and distribution differences of multiple indicators and substances from municipal sludge, dredged sludge, and river and lake sediments. The results demonstrated pH of multisource sludge was relatively stable in the neutral range. Organic matter and water content among municipal sludge were high and varied considerably between different wastewater treatment plants. Dredged sludge had an obviously higher sand content and wider particle distribution, which could be considered for graded utilization depending on its size. The nutrients composition of river and lake sediments was usually stable and special, with lower nitrogen and phosphorus content but higher potassium levels. The sources of heavy metals and persistent organic pollutants in multisource sludge were correlated, generally much higher among municipal sludge than dredged sludge and river and lake sediments, which were the most important limitation for final land utilization. Despite various properties of multisource sludge, the final fate and destination have some overall similarities, which need to be supplemented and improved by standards and laws. The study provided a preliminary analysis of suitable technical routes for municipal sludge, dredged sludge, river and lake sediments based on their different characteristics respectively, which was of great significance for multisource sludge co-treatment and disposal in the future of China.

Endoscopic ultrasound diagnosis system based on deep learning in images capture and segmentation training of solid pancreatic masses

BACKGROUND

Early detection of solid pancreatic masses through contrast-enhanced harmonic endoscopic ultrasound (CH-EUS) is important. But CH-EUS is difficult to learn.

PURPOSE

To design a deep learning-based contrast-enhanced harmonic endoscopic ultrasound diagnosis system (CH-EUS MASTER) for real-time capture and segmentation of solid pancreatic masses and to verify its value in the training of pancreatic mass identification under endoscopic ultrasound.

METHODS

We designed a real-time capture and segmentation model for solid pancreatic masses and then collected 4530 EUS images of pancreatic masses retrospectively, used for training and testing of this model at a ratio of 8:2. The model is loaded into the EUS host computer to establish the CH-EUS MASTER system. A crossover trial was then conducted to evaluate the model's value in EUS trainee training by successfully conducting two groups of EUS trainees in model learning and trainer-guided training. The intersection over union (IoU) and the time to find the lesion were used to evaluate the model performance metrics, and the Mann-Whitney test was used to compare the IoU and the time to find the lesion in different groups of subjects. Paired t-test was used to compare the effects before and after training. When α≤0.05, it is considered to have a significant statistical difference.

RESULTS

The model test showed that the model successfully captured and segmented the pancreatic solid mass region in 906 EUS images. The real-time capture and segmentation model had a Dice coefficient of 0.763, a recall rate of 0.941, a precision rate of 0.642, and an accuracy of 0.842 (when the threshold is set to 0.5), and the median IoU of all cases was 0.731. For the AI training effect, the average IoU of eight trainees improved from 0.80 to 0.87(95% CI, 0.032∼0.096; P = 0.002). The average time for identifying lesions in the pancreatic body and tail improved from 22.75 seconds to 17.98 seconds (95% CI, 3.664∼5.886; P < 0.01). The average time for identifying lesions in the pancreatic head and uncinate process improved from 34.21 seconds to 25.92 seconds (95% CI, 7.661∼8.913; P < 0.01).

CONCLUSION

CH-EUS MASTER can provide an effect equivalent to trainer guidance in training pancreatic solid mass identification and segmentation under EUS. This article is protected by copyright. All rights reserved.

Arc ubiquitination regulates endoplasmic reticulum-mediated Ca2+ release and CaMKII signaling

Synaptic plasticity relies on rapid, yet spatially precise signaling to alter synaptic strength. Arc is a brain enriched protein that is rapidly expressed during learning-related behaviors and is essential for regulating metabotropic glutamate receptor-mediated long-term depression (mGluR-LTD). We previously showed that disrupting the ubiquitination capacity of Arc enhances mGluR-LTD; however, the consequences of Arc ubiquitination on other mGluR-mediated signaling events is poorly characterized. Here we find that pharmacological activation of Group I mGluRs with S-3,5-dihydroxyphenylglycine (DHPG) increases Ca2+ release from the endoplasmic reticulum (ER). Disrupting Arc ubiquitination on key amino acid residues enhances DHPG-induced ER-mediated Ca2+ release. These alterations were observed in all neuronal subregions except secondary branchpoints. Deficits in Arc ubiquitination altered Arc self-assembly and enhanced its interaction with calcium/calmodulin-dependent protein kinase IIb (CaMKIIb) and constitutively active forms of CaMKII in HEK293 cells. Colocalization of Arc and CaMKII was altered in cultured hippocampal neurons, with the notable exception of secondary branchpoints. Finally, disruptions in Arc ubiquitination were found to increase Arc interaction with the integral ER protein Calnexin. These results suggest a previously unknown role for Arc ubiquitination in the fine tuning of ER-mediated Ca2+ signaling that may support mGluR-LTD, which in turn, may regulate CaMKII and its interactions with Arc.

Erratum: The E3 ubiquitin ligase RNF216/TRIAD3 is a key coordinator of the hypothalamic-pituitary-gonadal axis

[This corrects the article DOI: 10.1016/j.isci.2022.104386.].

Association between caregiver ability and quality of life for people with inflammatory bowel disease: The mediation effect of positive feelings of caregivers

Inflammatory bowel disease (IBD) is an incurable digestive disease. Since patients have to live with it, improving patients' quality of life is important. Caregiver's positive feelings and closeness may have a positive effect on patients' quality of life. We hypothesized that caregiver's positive feeling affected patient's quality of life through caregiver's caring ability, and closeness might be the upstream of this chain. In this study, we conducted a single-center cross-sectional survey by questionnaire in China to tested the hypothesis. A total of 181 patient-caregiver pairs were included. The short version of the IBD questionnaire (SIBDQ), the twelve-item short-form health survey (SF-12), the positive aspects of caregiving (PAC) and Capacity Scale of caregivers were used to collect data. All the data were collected in one interview. Spearman correlation and Bootstrap method were used to analyze the data. Mediation analysis results indicated that caregiver's caring ability mediated the association between caregiver's positive feelings and patients' quality of life (p < 0.01), which explained 34.1% of the total variation of patients' quality of life. Mediation analysis results also revealed that patient-evaluated or caregiver-evaluated closeness had a positive effect on patients' quality of life through caregiver's positive feeling and caregiver's caring ability (p < 0.05), which explained 2.1 and 2.3% of the variation of patients' quality of life. Caregiver's positive feelings were related to caregivers' quality of life (p < 0.01), but there was no significant association between caregivers' ability and caregivers' quality of life. In summary, our model revealed that caregiver's positive feeling affected patients' quality of life through caregiver's caring ability.

Atrial myocyte-derived exosomal microRNA contributes to atrial fibrosis in atrial fibrillation

Background

Atrial fibrosis plays a critical role in the development of atrial fibrillation (AF). Exosomes are a promising cell-free therapeutic approach for the treatment of AF. The purposes of this study were to explore the mechanisms by which exosomes derived from atrial myocytes regulate atrial remodeling and to determine whether their manipulation facilitates the therapeutic modulation of potential fibrotic abnormalities during AF.

Methods

We isolated exosomes from atrial myocytes and patient serum, and microRNA (miRNA) sequencing was used to analyze exosomal miRNAs in exosomes derived from atrial myocytes and patient serum. mRNA sequencing and bioinformatics analyses corroborated the key genes that were direct targets of miR-210-3p.

Results

The miRNA sequencing analysis identified that miR-210-3p expression was significantly increased in exosomes from tachypacing atrial myocytes and serum from patients with AF. In vitro, the miR-210-3p inhibitor reversed tachypacing-induced proliferation and collagen synthesis in atrial fibroblasts. Accordingly, miR-210-3p knock out (KO) reduced the incidence of AF and ameliorated atrial fibrosis induced by Ang II. The mRNA sequencing analysis and dual-luciferase reporter assay showed that glycerol-3-phosphate dehydrogenase 1-like (GPD1L) is a potential target gene of miR-210-3p. The functional analysis suggested that GPD1L regulated atrial fibrosis via the PI3K/AKT signaling pathway. In addition, silencing GPD1L in atrial fibroblasts induced cell proliferation, and these effects were reversed by a PI3K inhibitor (LY294002).

Conclusions

Atrial myocyte-derived exosomal miR-210-3p promoted cell proliferation and collagen synthesis by inhibiting GPD1L in atrial fibroblasts. Preventing pathological crosstalk between atrial myocytes and fibroblasts may be a novel target to ameliorate atrial fibrosis in patients with AF.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03617-y.

HMOX1 promotes lung adenocarcinoma metastasis by affecting macrophages and mitochondrion complexes

Background

Metastasis is the leading cause of lung adenocarcinoma (LUAD) patient death. However, the mechanism of metastasis is unclear. We performed bioinformatic analyses for HMOX1 (Heme oxygenase-1), aiming to explore its role in LUAD metastasis.

Methods

Pan-cancer analysis was first used to identify the metastasis-associated role of HMOX1 in LUAD. HMOX1-related genomic alterations were then investigated. Based on functional enrichment, we systematically correlated HMOX1 with immunological characteristics and mitochondrial activities. Furthermore, weighted gene co-expression network analysis (WGCNA) was applied to construct the HMOX1-mediated metastasis regulatory network, which was then validated at the proteomic level. Finally, we conducted the survival analysis and predicted the potential drugs to target the HMOX1 network.

Results

HMOX1 expression was significantly associated with epithelial-mesenchymal transition (EMT) and lymph and distant metastasis in LUAD. High HMOX1 levels exhibited higher macrophage infiltration and lower mitochondrial complex expression. WGCNA showed a group of module genes co-regulating the traits mentioned above. Subsequently, we constructed an HMOX1-mediated macrophage-mitochondrion-EMT metastasis regulatory network in LUAD. The network had a high inner correlation at the proteomic level and efficiently predicted prognosis. Finally, we predicted 9 potential drugs targeting HMOX1-mediated metastasis in LUAD, like chloroxine and isoliquiritigenin.

Conclusions

Our analysis elaborates on the role of HMOX1 in LUAD metastasis and identified a highly prognostic HMOX1-mediated metastasis regulatory network. Novel potential drugs targeting the HMOX1 network were also proposed, which should be tested for their activity against LUAD metastasis in future studies.

Iron(II)-Catalyzed Nitrene Transfer Reaction of Sulfoxides with N-Acyloxyamides

An iron(II)-catalyzed nitrene transfer reaction of sulfoxides with N-acyloxyamides has been developed, leading to the efficient construction of N-acyl sulfoximines with high functional-group compatibility. The current catalytic transformation was carried out under an air atmosphere at ambient temperature and could be scaled up to gram scale with a catalyst loading of 1 mol %. Application of the methodology was demonstrated by facile C-H acetoxylation and olefination using the N-acyl sulfoximine as the directing group.

Akkermansia muciniphila prevents cold-related atrial fibrillation in rats by modulation of TMAO induced cardiac pyroptosis

Background

Cold exposure is one of the most important risk factors for atrial fibrillation (AF), and closely related to the poor prognosis of AF patients. However, the mechanisms underlying cold-related AF are poorly understood.

Methods

Various techniques including 16S rRNA gene sequencing, fecal microbiota transplantation, and electrophysiological examination were used to determine whether gut microbiota dysbiosis promotes cold-related AF. Metabonomics were performed to investigate changes in fecal trimethylamine (TMA) and plasma trimethylamine N-oxide (TMAO) during cold exposure. The detailed mechanism underlying cold-related AF were examined in vitro. Transgenic mice were constructed to explore the role of pyroptosis in cold-related AF. The human cohort was used to evaluate the correlation between A. muciniphila and cold-related AF.

Findings

We found that cold exposure caused elevated susceptibility to AF and reduced abundance of Akkermansia muciniphila (A. muciniphila) in rats. Intriguingly, oral supplementation of A. muciniphila ameliorated the pro-AF property induced by cold exposure. Mechanistically, cold exposure disrupted the A. muciniphila, by which elevated the level of trimethylamine N-oxide (TMAO) through modulation of the microbial enzymes involved in trimethylamine (TMA) synthesis. Correspondingly, progressively increased plasma TMAO levels were validated in human subjects during cold weather. Raised TMAO enhanced the infiltration of M1 macrophages in atria and increased the expression of Casp1-p20 and cleaved-GSDMD, ultimately causing atrial structural remodeling. Furthermore, the mice with conditional deletion of caspase1 exhibited resistance to cold-related AF. More importantly, a cross-sectional clinical study revealed that the reduction of A. muciniphila abundance was an independent risk factor for cold-related AF in human subjects.

Interpretation

Our findings revealed a novel causal role of aberrant gut microbiota and metabolites in pathogenesis of cold-related AF, which raises the possibility of selectively targeting microbiota and microbial metabolites as a potential therapeutic strategy for cold-related AF.

Funding

This work was supported by grants from the State Key Program of National Natural Science Foundation of China (No.81830012), and National Natural Science Foundation of China (No.82070336, No.81974024), Youth Program of the National Natural Science Foundation of China (No.81900374, No.81900302), and Excellent Young Medical Talents supporting project in the First Affiliated Hospital of Harbin Medical University (No. HYD2020YQ0001).

Resolving the Heterogeneous Adsorption of Antibody Fragment on a 2D Layered Molybdenum Disulfide by Super-Resolution Imaging

The development of nanomaterials such as two-dimensional (2D) layered materials advanced applications in many fields, including biosensors format based on field-effect transistors. The unique physical and chemical properties of 2D layered materials enable the detection limit of biomolecules as low as ∼1 pg/mL. The majority of 2D layered materials contain different structural features and defects introduced in chemical synthesis and fabrication processing. These structural features have different physicochemical properties, causing heterogeneous adsorption of bioreceptors like antibodies, enzymes, etc. Understanding the correlation between the adsorption of bioreceptors and properties of structural features is essential for building highly efficient, sensitive biosensors based on 2D layered materials. Here, we utilize a single-molecule localization-based super-resolved fluorescence imaging method to unveil the inhomogeneous adsorption of antibody fragments on 2D layered molybdenum disulfide (MoS₂). The surface coverage of antibody fragments on MoS₂ thin flakes is quantitatively measured and compared at different structural features and different layer thicknesses. The methodology in the current work can be extended to study bioreceptor adsorption on other types of 2D layered materials and pave a way to improve biosensors' sensitivity based on defect engineering 2D layered materials.

The E3 ubiquitin ligase RNF216/TRIAD3 is a key coordinator of the hypothalamic-pituitary-gonadal axis

Recessive mutations in RNF216/TRIAD3 cause Gordon Holmes syndrome (GHS), in which dysfunction of the hypothalamic-pituitary-gonadal (HPG) axis and neurodegeneration are thought to be core phenotypes. We knocked out Rnf216/Triad3 in a gonadotropin-releasing hormone (GnRH) hypothalamic cell line. Rnf216/Triad3 knockout (KO) cells had decreased steady-state GnRH and calcium transients. Rnf216/Triad3 KO adult mice had reductions in GnRH neuron soma size and GnRH production without changes in neuron densities. In addition, KO male mice had smaller testicular volumes that were accompanied by an abnormal release of inhibin B and follicle-stimulating hormone, whereas KO females exhibited irregular estrous cycling. KO males, but not females, had reactive microglia in the hypothalamus. Conditional deletion of Rnf216/Triad3 in neural stem cells caused abnormal microglia expression in males, but reproductive function remained unaffected. Our findings show that dysfunction of RNF216/TRIAD3 affects the HPG axis and microglia in a region- and sex-dependent manner, implicating sex-specific therapeutic interventions for GHS.

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Rnf216/Triad3 controls GnRH production and intrinsic hypothalamic cell activity

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Rnf216/Triad3 knockout male mice have greater reproductive impairments than females

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Rnf216/Triad3 controls the HPG axis differently in males and females

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Rnf216/Triad3 knockout male mice have reactive microglia in the hypothalamus

Can visceral adipose tissue and skeletal muscle predict recurrence of newly diagnosed Crohn's disease in different treatments

BACKGROUND AND AIMS

It is crucial to manage the recurrence of Crohn's disease (CD). This study is aimed to explore whether visceral adipose tissue (VAT) and skeletal muscle (SM) are associated with the recurrence of CD upon different treatments.

METHODS

All patients with a definite diagnosis of CD were retrospectively divided into three groups according to distinct treatment regimens: 5-amino salicylic acid group (Group A), steroids + azathioprine (Group B) and biologics (Group C). The pretreatment computerized tomography (CT) images and clinical data were collected. The VAT area, mesenteric fat index (MFI), the ratio of VAT area to fat mass (VAT area/FM) were assessed. The primary end point was the recurrence of CD within 1 year of follow-up.

RESULTS

A total of 171 CD patients were enrolled, including 57 (33.33%) patients in Group A, 70 (40.94%) patients in Group B and 44 (25.73%) patients in Group C. Patients with 1-year recurrence had higher MFI (P = 0.011) and VAT area/FM (P = 0.000). ROC curve demonstrated that patients with the ratio of VAT area/FM and MFI higher than 0.578 and 1.394 tended to have recurrence with the AUC of 0.707 and 0.709. Similar results could be observed in Group A & B but not in Group C.

CONCLUSIONS

High VAT area/FM and MFI are related to recurrence within 1 year for newly diagnosed CD patients treated by 5-amino salicylic or azathioprine + steroids rather than biologics. We could not observe any radiological data associated with the recurrence of CD patients under biological treatment.

A rare case of right upper lung cancer with azygos lobe and partial anomalous pulmonary venous return

BACKGROUND

The azygos lobe (AL) combined with partial anomalous pulmonary venous return (PAPVR) is comparatively uncommon as well as in radical surgery for right lung cancer.

CASE PRESENTATION

We herein present an extremely rare case of lung cancer coexisting with AL and asymptomatic PAPVR, which was diagnosed with preoperative contrast three-dimensional reconstruction and received radical surgery by thoracoscopy. During the surgery, we preserved azygos vein successfully and found a split type of PAPVR in right upper pulmonary vein.

CONCLUSIONS

AL combined with PAPVR may cause confusion on the vascular separation and disconnection of the right pulmonary hilar. However, preoperative 3D reconstruction is more conducive to the correct performing of this type of surgery.

Endoscopists' Acceptance on the Implementation of Artificial Intelligence in Gastrointestinal Endoscopy: Development and Case Analysis of a Scale

Background

The purpose of this paper is to develop and validate a standardized endoscopist acceptance scale for the implementation of artificial intelligence (AI) in gastrointestinal endoscopy.

Methods

After investigating endoscopists who have previously used AI and consulting with AI experts, we developed a provisional scale to measure the acceptance of AI as used in gastrointestinal endoscopy that was then distributed to a sample of endoscopists who have used AI. After analyzing the feedback data collected on the provisional scale, we developed a new formal scale with four factors. Cronbach's alpha, confirmatory factor analysis (CFA), content validity, and related validity were conducted to test the reliability and validity of the formal scale. We also constructed a receiver operating characteristic (ROC) curve in order to determine the scale's ability to distinguish higher acceptance and satisfaction.

Results

A total of 210 valid formal scale data points were collected. The overall Cronbach's alpha was 0.904. All the factor loadings were >0.50, of which the highest factor loading was 0.86 and the lowest was 0.54 (AVE = 0.580, CR = 0.953). The correlation coefficient between the total score of the scale and the satisfaction score was 0.876, and the area under the ROC curve was 0.949 ± 0.031. Endoscopists with a score higher than 50 tend to be accepting and satisfied with AI.

Conclusion

This study yielded a viable questionnaire to measure the acceptance among endoscopists of the implementation of AI in gastroenterology.

Effect of remimazolam tosilate on early cognitive function in elderly patients undergoing upper gastrointestinal endoscopy

BACKGROUND AND AIM

Remimazolam tosilate (RT) is under evaluation as a sedative for endoscopic procedures. Herein, we aimed to evaluate safety including cognition recovery of RT administered in elderly patients undergoing upper gastrointestinal endoscopy and assess its safety dosage.

METHODS

Ninety-nine patients presenting for upper gastrointestinal endoscopy were randomized to receive 0.1 mg/kg RT (R1) or 0.2 mg/kg RT (R2), or propofol (P). Cognitive functions (memory, attention, and executive function) were measured via neuropsychological tests conducted before sedation and 5 min after recovery to full alertness. Adverse events were also assessed.

RESULTS

There were no statistical differences between postoperative and baseline results for R1 group and P group, whereas those for R2 group revealed worsened postoperative cognitive functions (immediate recall and short delay recall) than baseline (P < 0.05). Compared with P group, Scores demonstrated worse restoration of immediate recall in R1 group, immediate recall, short-delayed recall, and attention function in R2 group (P < 0.05). Patients in R2 group had a longer sedation time (12.09 vs 8.27 vs 8.21 min; P < 0.001) and recovery time (6.85 vs 3.82 vs 4.33 min; P < 0.001) than that in R1 group and P group. Moreover, the incidence of hypotension was 3.0% in R1 group, whereas it was 21.2% in R2 group and 48.5% in P group (P < 0.05).

CONCLUSION

The addition of 0.1 mg/kg RT as an adjunct to opiate sedation for upper gastrointestinal endoscopy not only achieves more stable perioperative hemodynamics but also achieves acceptable neuropsychiatric functions in elderly patients.

Imaging Dynamic Processes in Multiple Dimensions and Length Scales

Optical microscopy has become an invaluable tool for investigating complex samples. Over the years, many advances to optical microscopes have been made that have allowed us to uncover new insights into the samples studied. Dynamic changes in biological and chemical systems are of utmost importance to study. To probe these samples, multidimensional approaches have been developed to acquire a fuller understanding of the system of interest. These dimensions include the spatial information, such as the three-dimensional coordinates and orientation of the optical probes, and additional chemical and physical properties through combining microscopy with various spectroscopic techniques. In this review, we survey the field of multidimensional microscopy and provide an outlook on the field and challenges that may arise. Expected final online publication date for the Annual Review of Physical Chemistry, Volume 73 is April 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

NtMYB305a binds to the jasmonate-responsive GAG region of NtPMT1a promoter to regulate nicotine biosynthesis

MYB transcription factors play essential roles in regulating plant secondary metabolism and jasmonate (JA) signaling. Putrescine N-methyltransferase is a key JA-regulated step in the biosynthesis of nicotine, an alkaloidal compound highly accumulated in Nicotiana spp. Here we report the identification of NtMYB305a in tobacco (Nicotiana tabacum) as a regulatory component of nicotine biosynthesis and demonstrate that it binds to the JA-responsive GAG region, which comprises a G-box, an AT-rich motif, and a GCC-box-like element, in the NtPMT1a promoter. Yeast one-hybrid analysis, electrophoretic mobility shift assay and chromatin immunoprecipitation assays showed that NtMYB305a binds to the GAG region in vitro and in vivo. Binding specifically occurs at the ∼30-bp AT-rich motif in a G/C-base-independent manner, thus defining the AT-rich motif as previously unknown MYB-binding element. NtMYB305a localized in the nucleus of tobacco cells where it is capable of activating the expression of a 4×GAG-driven GUS reporter in an AT-rich motif-dependent manner. NtMYB305a positively regulates nicotine biosynthesis and the expression of NtPMT and other nicotine pathway genes. NtMYB305a acts synergistically with NtMYC2a to regulate nicotine biosynthesis, but no interaction between these two proteins was detected. This identification of NtMYB305a provides insights into the regulation of nicotine biosynthesis and extends the roles played by MYB transcription factors in plant secondary metabolism.

bHLH Transcription Factor NtMYC2a Regulates Carbohydrate Metabolism during the Pollen Development of Tobacco (Nicotiana tabacum L. cv. TN90)

Basic helix-loop-helix (bHLH) transcription factor MYC2 regulates plant growth and development in many aspects through the jasmonic acid (JA) signaling pathway, while the role of MYC2 in plant carbohydrate metabolism has not been reported. Here, we generated NtMYC2a-overexpressing (NtMYC2a-OE) and RNA-interference-mediated knockdown (NtMYC2a-RI) transgenic plants of tobacco (Nicotiana tabacum L. cv. TN90) to investigate the role of NtMYC2a in carbohydrate metabolism and pollen development. Results showed that NtMYC2a regulates the starch accumulation and the starch-sugar conversion of floral organs, especially in pollen. The RT-qPCR analysis showed that the expression of starch-metabolic-related genes, AGPs, SS2 and BAM1, were regulated by NtMYC2a in the pollen grain, anther wall and ovary of tobacco plants. The process of pollen maturation was accelerated in NtMYC2a-OE plants and was delayed in NtMYC2a-RI plants, but the manipulation of NtMYC2a expression did not abolish the pollen fertility of the transgenic plants. Intriguingly, overexpression of NtMYC2a also enhanced the soluble carbohydrate accumulation in tobacco ovaries. Overall, our results demonstrated that the bHLH transcription factor NtMYC2a plays an important role in regulating the carbohydrate metabolism during pollen maturation in tobacco.

Variations of heavy metals, nutrients, POPs and particle size distribution during "sludge anaerobic digestion-solar drying-land utilization process": Case study in China

Sewage sludge was rich in pollutants such as heavy metals, nutrients and persistent organic pollutants. Anaerobic digestion can effectively degrade the pollutants while achieving sludge stabilization and reduction. This study took a sludge treatment plant located in Anhui Province, China as a case study, investigating the variations of multiple substances and particle size distribution during sludge anaerobic digestion-solar drying-land utilization process. The results demonstrated anaerobic digestion had a positive effect on the removal of heavy metals, nutrients and persistent organic pollutants, for polycyclic aromatic hydrocarbons, antibiotics and disinfection by-products with 41.38%, 62.26% and 68.68%, respectively, which were related to their molecular weight and structure. Large amounts of heavy metals would flow away with liquid digestate, in which Cr and Hg were the most and least, 90.44% and 41.95% respectively. The degradation of extracellular polymers in this process led to a decrease in particle size distribution, which caused the deterioration of sludge dewatering performance. Nutrients and water content increased and decreased respectively during solar drying along with the volatilization of organic matter under high temperature, which was beneficial for the final sludge product to subsequent land utilization. No significant correlation was demonstrated between heavy metals and sludge properties besides electrical conductivity. The study provided a new thinking on the variations of different substances and the way of actual treatment and disposal from the perspective of sludge anaerobic digestion-solar drying-land utilization process, which had a considerable significance for the further promotion and application of anaerobic digestion process in China's engineering community.

Characterizing ammonia emissions from water bodies using dynamic floating chambers

Ammonia (NH₃) is the most important alkaline gas in the atmosphere and plays a central role in atmospheric pollution and the global N cycle. Water bodies receive increasing nitrogen inputs from effluents and atmospheric deposition due to anthropogenic activities and are regarded as the major natural NH₃ and NH₄⁺ sinks. In this work, floating dynamic flux chambers were deployed at four types of freshwater (rivers, large reservoirs, medium-sized reservoirs and ponds) systems and a coastal seawater system to estimate the water-air NH₃ emission fluxes. The NH₃ emission fluxes of rivers (26.4 μg NH₃ m^-2 h^-1) were significantly higher than those of other types of freshwater systems, and the NH₃ flux of offshore water was unexpectedly high (3.9 μg NH₃ m^-2 h^-1). The ammonium content and water temperature were the most important factors driving NH₃ emissions from water bodies. The global NH₃ emissions from water bodies reached 8.88 TgN a^-1, and this value will increase persistently with global warming and water quality deterioration. Water bodies that are relatively eutrophic and directly affected by anthropogenic activities should be considered reservoirs of inputted N instead of permanent sinks.

Tuning Protein Dynamics to Sense Rapid Endoplasmic-Reticulum Calcium Dynamics

Multi-scale calcium (Ca²⁺ ) dynamics, exhibiting wide-ranging temporal kinetics, constitutes a ubiquitous mode of signal transduction. We report a novel endoplasmic-reticulum (ER)-targeted Ca²⁺ indicator, R-CatchER, which showed superior kinetics in vitro (k_off ≥2×10³  s^-1 , k_on ≥7×10⁶  M^-1  s^-1 ) and in multiple cell types. R-CatchER captured spatiotemporal ER Ca²⁺ dynamics in neurons and hotspots at dendritic branchpoints, enabled the first report of ER Ca²⁺ oscillations mediated by calcium sensing receptors (CaSRs), and revealed ER Ca²⁺ -based functional cooperativity of CaSR. We elucidate the mechanism of R-CatchER and propose a principle to rationally design genetically encoded Ca²⁺ indicators with a single Ca²⁺ -binding site and fast kinetics by tuning rapid fluorescent-protein dynamics and the electrostatic potential around the chromophore. The design principle is supported by the development of G-CatchER2, an upgrade of our previous (G-)CatchER with improved dynamic range. Our work may facilitate protein design, visualizing Ca²⁺ dynamics, and drug discovery.

Extracellular calcium alters calcium-sensing receptor network integrating intracellular calcium-signaling and related key pathway

G-protein-coupled receptors (GPCRs) are a target for over 34% of current drugs. The calcium-sensing receptor (CaSR), a family C GPCR, regulates systemic calcium (Ca²⁺) homeostasis that is critical for many physiological, calciotropical, and noncalciotropical outcomes in multiple organs. However, the mechanisms by which extracellular Ca²⁺ (Ca²⁺_ex) and the CaSR mediate networks of intracellular Ca²⁺-signaling and players involved throughout the life cycle of CaSR are largely unknown. Here we report the first CaSR protein–protein interactome with 94 novel putative and 8 previously published interactors using proteomics. Ca²⁺_ex promotes enrichment of 66% of the identified CaSR interactors, pertaining to Ca²⁺ dynamics, endocytosis, degradation, trafficking, and primarily to protein processing in the endoplasmic reticulum (ER). These enhanced ER-related processes are governed by Ca²⁺_ex-activated CaSR which directly modulates ER-Ca²⁺ (Ca²⁺_ER), as monitored by a novel ER targeted Ca²⁺-sensor. Moreover, we validated the Ca²⁺_ex dependent colocalizations and interactions of CaSR with ER-protein processing chaperone, 78-kDa glucose regulated protein (GRP78), and with trafficking-related protein. Live cell imaging results indicated that CaSR and vesicle-associated membrane protein-associated A (VAPA) are inter-dependent during Ca²⁺_ex induced enhancement of near-cell membrane expression. This study significantly extends the repertoire of the CaSR interactome and reveals likely novel players and pathways of CaSR participating in Ca²⁺_ER dynamics, agonist mediated ER-protein processing and surface expression.

Single-molecule photocatalytic dynamics at individual defects in two-dimensional layered materials

The insightful comprehension of in situ catalytic dynamics at individual structural defects of two-dimensional (2D) layered material, which is crucial for the design of high-performance catalysts via defect engineering, is still missing. Here, we resolved single-molecule trajectories resulted from photocatalytic activities at individual structural features (i.e., basal plane, edge, wrinkle, and vacancy) in 2D layered indium selenide (InSe) in situ to quantitatively reveal heterogeneous photocatalytic dynamics and surface diffusion behaviors. The highest catalytic activity was found at vacancy in a four-layer InSe, up to ~30× higher than that on the basal plane. Moreover, lower adsorption strength of reactant and slower dissociation/diffusion rates of product were found at more photocatalytic active defects. These distinct dynamic properties are determined by lattice structures/electronic energy levels of defects and layer thickness of supported InSe. Our findings shed light on the fundamental understanding of photocatalysis at defects and guide the rational defect engineering.

Dynamin-dependent vesicle twist at the final stage of clathrin-mediated endocytosis

Dynamin plays an important role in clathrin-mediated endocytosis (CME) by cutting the neck of nascent vesicles from the cell membrane. Here through using gold nanorods as cargos to image dynamin action during live CME, we show that near the peak of dynamin accumulation, the cargo-containing vesicles always exhibit abrupt, right-handed rotations that finish in a short time (~0.28 s). The large and quick twist, herein named the super twist, is the result of the coordinated dynamin helix action upon GTP hydrolysis. After the super twist, the rotational freedom of the vesicle drastically increases, accompanied with simultaneous or delayed translational movement, indicating that it detaches from the cell membrane. These observations suggest that dynamin-mediated scission involves a large torque generated by coordinated actions of multiple dynamins in the helix, which is the main driving force for vesicle scission.

MiR-199a-5p suppresses proliferation and invasion of human laryngeal cancer cells

OBJECTIVE

To explore the roles of micro ribonucleic acid (miR)-199a-5p in the proliferation, apoptosis, invasion and metastasis of laryngeal cancer cells, and its molecular mechanisms.

PATIENTS AND METHODS

The expression of miR-199a-5p in 25 cases of laryngeal cancer tissues and paracancerous tissues was detected via quantitative real-time polymerase chain reaction (qRT-PCR). Its expression in TU212, TU686 and human epithelial type 2 (HEp-2) laryngeal cancer cell lines and normal nasopharyngeal epithelial cell line NP69 was also detected via qRT-PCR. HEp-2 cells were transiently transfected with miR-199a-5p mimic or miR-199a-5p inhibitor, and the expression of miR-199a-5p was verified using RT-PCR after transfection. The regulatory effects of miR-199a-5p on the proliferation, apoptosis, invasion and migration abilities of HEp-2 cells were observed through methyl thiazolyl tetrazolium (MTT) assay, flow cytometry, wound healing assay and transwell assay, respectively. Then, the mechanisms of miR-199a-5p in regulating Caspase-3 activity and epithelial-mesenchymal transition (EMT)-related proteins were further explored.

RESULTS

The qRT-PCR results revealed that miR-199a-5p was significantly lowly expressed in the laryngeal cancer tissues and tumor cell lines, and overexpression of miR-199a-5p substantially inhibited the proliferation of HEp-2 cells. According to the results of flow cytometry, overexpression of miR-199a-5p promoted the apoptosis of HEp-2 cells, whereas down-regulating miR-199a-5p suppressed their apoptosis. It was found that the activity of Caspase-3 was notably enhanced after overexpression of miR-199a-5p, which was evidently weakened after down-regulating miR-199a-5p. Wound healing assay and transwell assay results manifested that overexpressing miR-199a-5p weakened the invasion and migration abilities of HEp-2 cells, which were facilitated by down-regulating miR-199a-5p. Based on Western blotting results, miR-199a-5p regulated the expressions of E-cadherin, N-cadherin and vimentin. Overexpression of miR-199a-5p could inhibit EMT process, whereas suppressing miR-199a-5p could accelerate the process.

CONCLUSIONS

The expression of miR-199a-5p in laryngeal cancer tissues is substantially lower than that in the paracancerous tissues. MiR-199a-5p suppresses proliferation, invasion and migration in laryngeal cancer cell proliferation, while triggers cell apoptosis.

Single molecule fluorescence imaging of nanoconfinement in porous materials

This review covers recent progress in using single molecule fluorescence microscopy imaging to understand the nanoconfinement in porous materials. The single molecule approach unveils the static and dynamic heterogeneities from seemingly equal molecules by removing the ensemble averaging effect. Physicochemical processes including mass transport, surface adsorption/desorption, and chemical conversions within the confined space inside porous materials have been studied at nanometer spatial resolution, at the single nanopore level, with millisecond temporal resolution, and under real chemical reaction conditions. Understanding these physicochemical processes provides the ability to quantitatively measure the inhomogeneities of nanoconfinement effects from the confining properties, including morphologies, spatial arrangement, and trapping domains. Prospects and limitations of current single molecule imaging studies on nanoconfinement are also discussed.

CALD1 Modulates Gliomas Progression via Facilitating Tumor Angiogenesis

Simple Summary

Caldesmon has recently attracted attention in cancer due to its roles in cell migration, invasion and proliferation. l-CALD1 was also considered a potential serum marker for glioma. However, little is known about mechanisms underlying the effect of CALD1 on the microvascular facilitation and architecture in glioma. The purpose of this study was to explore the role of CALD1 for prediction glioma patient prognosis and in glioma angiogenesis. The findings of this study suggested that l-CALD1 could imply abnormal microvessels in anaplastic astrocytoma and GBM. In addition, high CI (calmodulin index) predicted worse prognosis in glioma, and furthermore, CALD1 may serve as a key marker for monitoring the progress of glioma and a novel target for therapy.

Abstract

Angiogenesis is more prominent in anaplastic gliomas and glioblastoma (GBM) than that in pilocytic and diffuse gliomas. Caldesmon (CALD1) plays roles in cell adhesion, cytoskeletal organization, and vascularization. However, limited information is available on mechanisms underlying the effect of CALD1 on the microvascular facilitation and architecture in glioma. In this study, we explored the role of CALD1 in gliomas by integrating bulk RNA-seq analysis and single cell RNA-seq analysis. A positive correlation between CALD1 expression and the gliomas’ pathological grade was noticed, according to the samples from the TCGA and CGGA database. Moreover, higher CALD1 expression samples showed worse clinical outcomes than lower CALD1 expression samples. Biofunction prediction suggested that CALD1 may affect glioma progression through modulating tumor angiogenesis. The map of the tumor microenvironment also depicted that more stromal cells, such as endothelial cells and pericytes, infiltrated in high CALD1 expression samples. CALD1 was found to be remarkably upregulated in neoplastic cells and was involved in tumorigenic processes of gliomas in single cell sequencing analysis. Histology and immunofluorescence analysis also indicated that CALD1 associates with vessel architecture, resulting in glioma grade progression. In conclusion, the present study implies that CALD1 may serve as putative marker monitoring the progress of glioma.

Large thyroglossal duct cyst of the neck mimicking cervical cystic lymphangioma in a neonate: a case report

Thyroglossal duct cyst (TGDC) is a congenital neck malformation, with a rate of approximately 7% in paediatric patients. TGDC is rarely detected in infants aged younger than 1 year. Even though TGDC is histologically benign, it is associated with preterm delivery or sudden infant death due to airway obstruction, with a mortality rate of 30% to 40%. We report a rare case of a neonate who presented with a large left lateral neck mass. At 7 to 8 months of gestation, magnetic resonance imaging of the foetal neck showed that there was a high possibility of a cervical cystic lymphangioma. The patient had normal vital signs and was afebrile. She was immediately transferred to our Ear, Nose, and Throat Department for further diagnosis and treatment. A computed tomography scan confirmed a large cystic mass that was positioned against a thyroglossal duct. Excision of the mass in the left neck was performed under general anaesthesia without resecting part of the hyoid bone. A histopathological examination confirmed the diagnosis of a TGDC. Follow-up at 1 year showed no recurrence.

Corrigendum: Laina Ndapewa Angula et al. External auditory canal haemorrhage as the first sign of internal carotid artery pseudoaneurysm, a rare case: a case report doi: 10.11604/pamj.2020.37.163.21968

This corrigendum corrects article “External auditory canal haemorrhage as the first sign of internal carotid artery pseudoaneurysm: a rare case” and its publication reference i.e. The Pan African Medical Journal. 2020; 37:163. Access corrected manuscript Pan African Medical Journal. 2020; 37: 163. doi: 10.11604/pamj.2020.37.163.21968. PubMed PMID: 33425196. PubMed Central PMCID: PMC7757232. Epub 2021/01/12. eng.

LINC01303 promotes the proliferation and migration of laryngeal carcinoma by regulating miR-200c/TIMP2 axis

BACKGROUND

It is reported that long non-coding RNA is crucial in many cancer progressions. But the function and regulatory mechanism of LINC01303 in human laryngeal squamous cell carcinoma (LSCC) remains unclear. Hence, this research aims at investigating the biological function and potential mechanism of LINC01303 in LSCC.

METHODS

Real-time quantitative PCR (qRT-PCR) was applied for the determination of LINC01303, miR-200c and TIMP metallopeptidase inhibitor 2 (TIMP2) expression in LSCC tissues and cell lines. Corresponding experiments were carried out to determine the impacts of LINC01303 on LSCC cell proliferation, apoptosis, migration and invasion. The interaction between LINC01303 and miR-200c was analyzed with bioinformatics analysis and luciferase activity analysis.

RESULTS

LINC01303 expression in LSCC tissues was notably higher than that in adjacent normal tissues. High LINC01303 expression was bound up with lymphatic metastasis and advanced clinical stage. In addition, inhibition of LINC01303 by siRNA could evidently block LSCC cell proliferation, induce apoptosis, and inhibit invasion and migration. Mechanically, LINC01303 acted as carcinogenic lncRNA in LSCC by regulating miR-200c/TIMP2 axis.

CONCLUSION

LINC01303 plays a carcinogenic part in LSCC carcinogenesis through regulating miR-200c/TIMP2 axis, which may become a promising target of LSCC therapy.

Rapid subcellular calcium responses and dynamics by calcium sensor G-CatchER. iScience 2021;24:102129. [PMID: 33665552 PMCID: PMC7900224 DOI: 10.1016/j.isci.2021.102129]

The precise spatiotemporal characteristics of subcellular calcium (Ca²⁺) transients are critical for the physiological processes. Here we report a green Ca²⁺ sensor called "G-CatchER⁺" using a protein design to report rapid local ER Ca²⁺ dynamics with significantly improved folding properties. G-CatchER⁺ exhibits a superior Ca²⁺ on rate to G-CEPIA1er and has a Ca²⁺-induced fluorescence lifetimes increase. G-CatchER⁺ also reports agonist/antagonist triggered Ca²⁺ dynamics in several cell types including primary neurons that are orchestrated by IP₃Rs, RyRs, and SERCAs with an ability to differentiate expression. Upon localization to the lumen of the RyR channel (G-CatchER⁺-JP45), we report a rapid local Ca²⁺ release that is likely due to calsequestrin. Transgenic expression of G-CatchER⁺ in Drosophila muscle demonstrates its utility as an in vivo reporter of stimulus-evoked SR local Ca²⁺ dynamics. G-CatchER⁺ will be an invaluable tool to examine local ER/SR Ca²⁺ dynamics and facilitate drug development associated with ER dysfunction.