Role of mitophagy in pulmonary hypertension: Targeting the mechanism and pharmacological intervention.

Mitophagy, a crucial pathway in eukaryotic cells, selectively eliminates dysfunctional mitochondria, thereby maintaining cellular homeostasis via mitochondrial quality control. Pulmonary hypertension (PH) refers to a pathological condition where pulmonary arterial pressure is abnormally elevated due to various reasons, and the underlying pathogenesis remains elusive. This article examines the molecular mechanisms underlying mitophagy, emphasizing its role in PH and the progress in elucidating related molecular signaling pathways. Additionally, it highlights current drug regulatory pathways, aiming to provide novel insights into the prevention and treatment of pulmonary hypertension.

Visual Strain Sensors Based on Fabry-Perot Structures for Structural Integrity Monitoring.

Strain sensors that can rapidly and efficiently detect strain distribution and magnitude are crucial for structural health monitoring and human-computer interactions. However, traditional electrical and optical strain sensors make access to structural health information challenging because data conversion is required, and they have intricate, delicate designs. Drawing inspiration from the moisture-responsive coloration of beetle wing sheaths, we propose using Ecoflex as a flexible substrate. This substrate is coated with a Fabry-Perot (F-P) optical structure, comprising a "reflective layer/stretchable interference cavity/reflective layer", creating a dynamic color-changing visual strain sensor. Upon the application of external stress, the flexible interference chamber of the sensor stretches and contracts, prompting a blue-shift in the structural reflection curve and displaying varying colors that correlate with the applied strain. The innovative flexible sensor can be attached to complex-shaped components, enabling the visual detection of structural integrity. This biomimetic visual strain sensor holds significant promise for real-time structural health monitoring applications.

G6PD is a prognostic biomarker correlated with immune infiltrates in lung adenocarcinoma and pulmonary arterial hypertension.

BACKGROUND: Lung adenocarcinoma (LUAD) with Pulmonary arterial hypertension (PAH) shows a poor prognosis. Detecting related genes is imperative for prognosis prediction. METHODS: The gene expression profiles of LUAD and PAH were acquired from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) database, respectively. The co-expression modules associated with LUAD and PAH were evaluated using the Weighted Gene Co-Expression Network Analysis (WGCNA). The relationship between key gene expression with immune-cell infiltration and the tumor immune microenvironment (TIME) was evaluated. We confirmed the mRNA and protein levels in vivo and vitro. G6PD knockdown was used to conduct the colony formation assay, transwell invasion assay, and scratch wound assay of A549 cells. EDU staining and CCK8 assay were performed on G6PD knockdown HPASMCs. We identified therapeutic drug molecules and performed molecular docking between the key gene and small drug molecules. RESULTS: Three major modules and 52 overlapped genes were recognized in LUAD and PAH. We identified the key gene G6PD, which was significantly upregulated in LUAD and PAH. In addition, we discovered a significant difference in infiltration for most immune cells between high- and low-G6PD expression groups. The mRNA and protein expressions of G6PD were significantly upregulated in LUAD and PAH. G6PD knockdown decreased proliferation, cloning, and migration of A549 cells and cell proliferation in HPASMCs. We screened five potential drug molecules against G6PD and targeted glutaraldehyde by molecular docking. CONCLUSIONS: This study reveals that G6PD is an immune-related biomarker and a possible therapeutic target for LUAD and PAH patients.

Expression and regulation of HIF-1a in hypoxic pulmonary hypertension: Focus on pathological mechanism and Pharmacological Treatment.

Hypoxia inducible factor-1(HIF-1), a heterodimeric transcription factor, is composed of two subunits (HIF-1α and HIF-1ß). It is considered as an important transcription factor for regulating oxygen changes in hypoxic environment, which can regulate the expression of various hypoxia-related target genes and play a role in acute and chronic hypoxia pulmonary vascular reactions. In this paper, the function and mechanism of HIF-1a expression and regulation in hypoxic pulmonary hypertension (HPH) were reviewed, and current candidate schemes for treating pulmonary hypertension by using HIF-1a as the target were introduced, so as to provide reference for studying the pathogenesis of HPH and screening effective treatment methods.

Flexible Strain Sensors Based on Bionic Parallel Vein-like Structures for Human Motion Monitoring.

In recent years, strain sensors have penetrated various fields. The capability of sensors to convert physical signals into electrical signals is of great importance in healthcare. However, it is still challenging to obtain sensors with high sensitivity, large operating range and low cost. In this paper, a stretchable strain sensor made of a double-layer conductive network, including a biomimetic multilayer graphene-Ecoflex (MLG-Ecoflex) substrate and a multilayer graphene-carbon nanotube (MLG-CNT) composite up-layer was developed. The combined action of the two layers led to an excellent performance with an operating range of up to 580% as well as a high sensitivity (gauge factor (GFmax) of 1517.94). In addition, a pressure sensor was further designed using the bionic vein-like structure with a multi-layer stacking of MLG-Ecoflex/MLG-CNT/MLG-Ecoflex to obtain a relatively high deformation along the direction of thickness. The device presented a high sensing performance (up to a sensitivity of 0.344 kPa-1) capable of monitoring small movements of the human body such as vocalizations and gestures. The good performance of the sensors together with a simple fabrication procedure (flip-molding) make it of potential use for some applications, for example human health monitoring and other areas of human interaction.

Untapping the Potential of Astragaloside IV in the Battle Against Respiratory Diseases.

Respiratory diseases are an emerging public health concern, that pose a risk to the global community. There, it is essential to establish effective treatments to reduce the global burden of respiratory diseases. Astragaloside IV (AS-IV) is a natural saponin isolated from Radix astragali (Huangqi in Chinese) used for thousands of years in Chinese medicine. This compound has become increasingly popular due to its potential anti-inflammatory, antioxidant, and anticancer properties. In the last decade, accumulated evidence has indicated the AS-IV protective effect against respiratory diseases. This article presents a current understanding of AS-IV roles and mechanisms in combatting respiratory diseases. The ability of the agent to suppress oxidative stress, cell proliferation, and epithelial-mesenchymal transition (EMT), to attenuate inflammatory responses, and modulate programmed cell death (PCD) will be discussed. This review highlights the current challenges in respiratory diseases and recommendations to improve disease management.

Celastrol: The new dawn in the treatment of vascular remodeling diseases.

Evidence is mounting that abnormal vascular remodeling leads to many cardiovascular diseases (CVDs). This suggests that vascular remodeling can be a crucial target for the prevention and treatment of CVDs. Recently, celastrol, an active ingredient of the broadly used Chinese herb Tripterygium wilfordii Hook F, has attracted extensive interest for its proven potential to improve vascular remodeling. Substantial evidence has shown that celastrol improves vascular remodeling by ameliorating inflammation, hyperproliferation, and migration of vascular smooth muscle cells, vascular calcification, endothelial dysfunction, extracellular matrix remodeling, and angiogenesis. Moreover, numerous reports have proven the positive effects of celastrol and its therapeutic promise in treating vascular remodeling diseases such as hypertension, atherosclerosis, and pulmonary artery hypertension. The present review summarizes and discusses the molecular mechanism of celastrol regulating vascular remodeling and provides preclinical proof for future clinical applications of celastrol.

Resistin-like molecules: a marker, mediator and therapeutic target for multiple diseases.

Resistin-like molecules (RELMs) are highly cysteine-rich proteins, including RELMα, RELMß, Resistin, and RELMγ. However, RELMs exhibit significant differences in structure, distribution, and function. The expression of RELMs is regulated by various signaling molecules, such as IL-4, IL-13, and their receptors. In addition, RELMs can mediate numerous signaling pathways, including HMGB1/RAGE, IL-4/IL-4Rα, PI3K/Akt/mTOR signaling pathways, and so on. RELMs proteins are involved in wide range of physiological and pathological processes, including inflammatory response, cell proliferation, glucose metabolism, barrier defense, etc., and participate in the progression of numerous diseases such as lung diseases, intestinal diseases, cardiovascular diseases, and cancers. Meanwhile, RELMs can serve as biomarkers, risk predictors, and therapeutic targets for these diseases. An in-depth understanding of the role of RELMs may provide novel targets or strategies for the treatment and prevention of related diseases. Video abstract.

The effect of maternal anxiety during pregnancy on the social emotional development among toddlers / 中国学校卫生

Objective@#To explore the impact of maternal anxiety during pregnancy on social emotional development of toddlers aged 1-3 year old, so as to provide references for scientific early parenting and early intervention for toddlers with social emotional difficulties.@*Methods@#From September 2022 to March 2023, a total of 815 toddlers aged 1-3 who underwent physical examinations and their mothers at Nantong Maternal and Child Health Hospital were enrolled. The Chinese Infant Toddler Social and Emotional Assessment (CITSEA) was used to evaluate the social emotional ability among toddlers. Maternal anxiety evaluated using the Self rating Anxiety Scale (SAS) during prenatal visit was collected.@*Results@#The average scores on the externalizing, internalizing, dysregulation and competence domains of the CITSEA were (49.40±9.48,47.42±9.60,48.67± 10.15 , 50.07± 10.20), respectively. Among boys, the score of externalizing domain (50.89±9.45) was higher than that of girls (48.76± 9.50 ), while the score of competence domain (49.22±10.30) was lower than that of girls (51.17±9.84), and the differences were statistically significant( t =2.10, -3.03, P <0.05). The detection rates of abnormalities in the externalizing, internalizing, dysregulation, and competence domains were 7.36%, 7.12%, 7.61%, and 7.24%, respectively. Among them, boys (8.43%,6.32%, 7.96 %,7.49%) and girls (6.19%, 7.99 %,7.22%,6.96%) showed no statistical differences ( χ 2=1.50, 0.85, 0.16, 0.09, P >0.05). There were significant differences in externalizing domain scores（47.77±9.52，49.56±8.95，52.51±9.77） and competence domain scores（51.70±10.38，49.65±10.05，46.68±10.03） among toddlers of different maternal anxiety（normal, mild, moderate to severe） （ F =7.05,7.10, P <0.01）. There were significant differences in the abnormal detection rate of externalizing domain （4.81%，7.54%，11.17%） and competence domain（4.81%，6.96%，11.73%）（ χ 2=6.60，7.98， P ＜0.05）.@*Conclusion@#Maternal anxiety during pregnancy has a negative impact on the social emotional development among toddlers. In order to improve social emotional development of toddlers, multidimensional social support and education during pregnancy should be carried out.

Transformation from polycythemia vera to acute promyelocytic leukemia: Case report and literature review.

INTRODUCTION: Transformation from chronic myeloproliferative neoplasm to acute leukemia is a feature of myeloproliferative neoplasm; however, the rate is not high. Transformation to acute promyelocytic leukemia is rare. Here, we report a case of transformation of polycythemia vera to acute promyelocytic leukemia and describe a process of clonal evolution that has not yet been reported. PATIENT CONCERNS: In this case, a 51-year-old woman was diagnosed with polycythemia vera and concomitant JAK2/V617F mutations in July 2019. She underwent intermittent phlebotomy and oral hydroxyurea irregularly. After 2 years, the patient complained of fatigue and poor sleep quality for 2 months. DIAGNOSIS: Further examination revealed marked hypercellularity and grade 1 bone marrow fibrosis with the PML/RARαV variant (23.85% mutation load), WT1-Exon1 (37.8%), WT1-Exon9 (4.1%), JAK3-Exon7 (49.3%), and RELN-Exon55 (45.8%). According to the World Health Organization classification of tumors of hematopoietic and lymphoid tissues, the patient was ultimately diagnosed with a rare transformation of polycythemia vera to acute promyelocytic leukemia. INTERVENTIONS: The patient underwent dual induction therapy with all-trans-retinoic acid and arsenic trioxide. OUTCOMES: After 28 days of induction therapy, the patient achieved complete remission, was compliant and the treatment was well tolerated. CONCLUSION: Polycythemia vera can transform into acute promyelocytic leukemia; therefore, it is important to review bone aspiration and other tests to perform a comprehensive assessment and monitor the disease status, to detect disease progression and intervene early when it transforms into acute promyelocytic leukemia.

[Association study of single nucleotide polymorphisms of AQP7 and AQP9 genes with type 2 diabetes mellitus among ethnic Han Chinese population].

OBJECTIVE: To assess the association of single nucleotide polymorphisms (SNP) of aquaporin 7 ( AQP7) and aquaporin 9 ( AQP9) genes and type 2 diabetes mellitus (T2DM) among ethnic Han Chinese population. METHODS: A case-control study involving 1194 subjects with T2DM and 1274 non-diabetic mellitus (NDM) subjects were enrolled. Genotypes of three SNPs (rs3758269 of AQP7 gene, rs16939881 and rs57139208 of AQP9 gene) were determined by using a MassArray method. The association of the three SNPs with T2DM was assess, and the correlation of glucose and lipid metabolism parameters with various SNP genotypes in the NDM group was analyzed. RESULTS: The allelic and genotypic frequencies of the three SNPs did not differ significantly between the two groups (P>0.05). Nor was there significant difference between the two groups with different genetic models (P>0.05). No significant association of genotypes of AQP7 gene rs3758269, AQP9 gene rs16939881 and rs57139208 with glucose and lipid metabolism parameters were observed in the NDM group (P>0.05). CONCLUSION: The rs3758269 in AQP7 gene and rs16939881 and rs57139208 in AQP9 gene are not associated with the genetic susceptibility of T2DM among ethnic Han Chinese population.

Establishment and verification of a nomogram and a preliminary study on predicting the clinical response of conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) in rheumatoid arthritis patients.

Background: Rheumatoid arthritis (RA) is an autoinflammatory disease, its core treatment principle is to achieve remission as soon as possible. There is no good prediction model that can accurately predict the remission rate of patients to choose a good treatment scheme. Here, we aimed to verify the prognostic value of some inflammatory indicators in RA and establish a prediction model to predict the remission rate after treatment. Methods: A total of 223 patients were enrolled at Qilu Hospital from June 2014 to June 2020. Baseline clinical data were collected and plasma was obtained to detect the inflammatory indicators. All patients were treated with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs). All patients were followed up and were recorded the time to reach the disease activity score-28 with erythrocyte sedimentation rate (DAS28-ESR) of <2.6. A total of 156 patients were randomly assigned to the development cohort, and 67 patients were assigned to the validation cohort. Inflammatory indicators in plasma were detected by enzyme-linked immunosorbent assay (ELISA). The predictive factors were screeded by using least absolute shrinkage and selection operator (LASSO) and Cox regression. The model was created and verified by using the standard method. A total of 6 independent risk factors were analyzed to construct a nomogram to predict the remission rate in 3, 6 and 12 months. Results: The remission rates after treatment in 3, 6 and 12 months were 38.76%, 58.91%, and 81.40%, respectively. Patient age, C-reactive protein (CRP), interleukin (IL)-6, galectin-9 (Gal-9), health assessment questionnaire (HAQ), and DAS28-ESR were included in the prognostic model to predict the remission rate. The resulting model had good discrimination ability in both the development cohort (C-index, 0.729) and the validation cohort (C-index, 0.710). Time-dependent receiver operating characteristic (ROC) curve, calibration analysis, and decision curve analysis (DCA) showed that the model has significant discriminant power and clinical practicability in predicting the remission rate. Conclusions: We established a new predictive model and validated it. The model can predict the remission rate in 3, 6 and 12 months after receiving csDMARDs treatment. By using this model, we can facilitate the identification of high-risk patients early and intervene with them as soon as possible.

Correlation between sensory characteristics and behavioral problems in children with autism spectrum disorder / 中国学校卫生

Objective@#To understand sensory characteristics and its correlation with behavioral problems among children with autism spectrum disorder (ASD), so as to provide reference basis for early diagnosis and comprehensive intervention of ASD children.@*Methods@#Using cross sectional survey, 193 ASD children trained by Nantong rehabilitation institutions were recruited from September 2021 to February 2022. All children were investigated with the Short Sensory Profile (SSP) and Parent Symptom Questionnaire (PSQ).@*Results@#Among the 193 ASD children, 106 (54.9%) children had abnormal sensory characteristics, including 45 (23.3%) with possible abnormalities and 61 (31.6%) with obvious abnormalities. The abnormal rate of auditory filtering was the highest in the seven dimensions, reaching 85.0%, followed by low strength/weakness, motor sensitivity, taste/smell sensitivity, low response/seeking sensation, vision/hearing sensitivity and tactile sensitivity. The total incidence of sensory abnormalities was 93.3%. There were significant differences in six dimensions of PSQ scale scores of ASD children with different degrees of sensory abnormalities, including conduct problems, learning problems, psychosomatic disorders, impulsive hyperactivity, anxiety and hyperactivity index ( H =38.89, 38.90, 19.53, 46.34, 34.54, 54.90, P <0.01). With the aggravation of sensory abnormalities in children with ASD, the scores of all dimensions of the PSQ scale increased significantly. The total score of SSP was negatively correlated with the six dimensions of conduct problems, learning problems, psychosomatic disorders, impulsive hyperactivity, anxiety and hyperactivity index in PSQ ( r =-0.53, -0.50, -0.32, -0.55, -0.43, -0.61, P <0.01).@*Conclusion@#ASD children generally have sensory abnormalities, which coincide with severity of behavioral problems. There is a positive correlation between sensory abnormalities and behavioral problems in ASD children. More attention should be paid to the abnormal sensory characteristics of children with ASD in the future diagnosis and treatment process.

Efficient Eradication of Bacterial Biofilms with Highly Specific Graphene-Based Nanocomposite Sheets.

Bacterial biofilms are usually resistant to antibiotics, thus powerful methods are required for removal. Nanomaterial involving a combination of treatment modalities recently has been recognized as an effective alternative to combat biofilm. However, its targeted and controlled release in bacterial infection is still a major challenge. Here, we present an intelligent phototherapeutic nanoplatform consisting of an aptamer (Apt), indocyanine green (ICG), and carboxyl-functionalized graphene oxide (GO-COOH), namely, ICG@GO-Apt, for targeted treatment of the biofilm formed by Salmonella Typhimurium. Since Apt-conjugated nanosheets (NSs) can specifically accumulate near abscess caused by the pathogens, they enhance greatly the local drug molecule concentration and promote their precise delivery. They can simultaneously generate heat and reactive oxygen species under near-infrared irradiation for photothermal/photodynamic therapy, thereby significantly enhancing biofilm elimination. The phototherapeutic ICG@GO-Apt also displays a good biocompatibility. More importantly, the multifunction phototherapeutic platform shows an efficient biofilm elimination with an efficiency of greater than 99.99% in an abscess formation model. Therefore, ICG@GO-Apt NSs with bacteria-targeting capability provide a reliable tool for clinical bacterial infection that circumvents antibiotic resistance.

Gold-Platinum Nanodots with High-Peroxidase-like Activity and Photothermal Conversion Efficiency for Antibacterial Therapy.

Combined therapeutic strategies for bacterial infection have attracted worldwide attention owing to their faster and more effective therapy with fewer side effects compared with monotherapy. In this work, gold-platinum nanodots (AuPtNDs) are simply and quickly synthesized by a one-step method. They not only exhibit powerful peroxidase-like activity but also confer a higher affinity for hydrogen peroxide (H2O2), which is 3.4 times that of horseradish peroxidase. Under 808 nm laser irradiation, AuPtNDs also have excellent photothermal conversion efficiency (50.53%) and strong photothermal stability. Excitingly, they can combat bacterial infection through the combination of chemodynamic and photothermal therapy. In vitro antibacterial results show that the combined antibacterial strategy has a broad-spectrum antibacterial property against both Escherichia coli (Gram negative, 97.1%) and Staphylococcus aureus (Gram positive, 99.3%). Animal experiments further show that nanodots can effectively promote the healing of bacterial infection wounds. In addition, owing to good biocompatibility and low toxicity, they are hardly traceable in the main organs of mice, which indicates that they can be well excreted through metabolism. These results reveal the application potential of AuPtNDs as a simple and magic multifunctional nanoparticle in antibacterial therapy and open up new applications for clinical anti-infective therapy in the near future.

Gold Nanomaterials as a Promising Integrated Tool for Diagnosis and Treatment of Pathogenic Infections-A Review.

This review summarizes research on functionalized gold nanomaterials as pathogen detection sensors and pathogen elimination integrated tools. After presenting the challenge of current severe threat from pathogenic bacteria and the increasingly serious growth rate of drug resistance, the first section mainly introduces the conspectus of gold nanostructures from synthesis, characterization, physicochemical properties and applications of gold nanomaterials. The next section deals with gold nanomaterials-based pathogen detection sensors such as colorimetric sensors, fluorescence sensors and Surface-Enhanced Raman Scattering sensors. We then discuss strategies based on gold nanomaterials for eliminating pathogenic infections, such as the dual sterilization strategy for grafting gold nanomaterials with antibacterial substances, photothermal antibacterial and photodynamic antibacterial methods. The fourth part briefly introduces the comprehensive strategy for diagnosis and sterilization of pathogen infection based on gold nanomaterials, such as the diagnosis and treatment strategy for pathogen infection using Roman signals real-time monitoring and photothermal sterilization. A concluding section that summarizes the current status and challenges of the novel diagnosis and treatment integrated strategy for pathogenic infections, gives an outlook on potential future perspectives.

Ferrocene-functionalized hybrid hydrogel dressing with high-adhesion for combating biofilm.

Bacterial infection is a common phenomenon in the process of postoperative wound healing. In severe cases, it may even lead to life-threatening, which brings a heavy burden to the clinical treatment and causes huge losses to the society and economy. As one of the most commonly applied medical materials for wound treatment, hydrogel dressings are mainly used to cover and protect wounds and provide a favorable environment to facilitate wound healing. In this work, we developed an antibacterial hydrogel dressing (Fc-PAAM) with high adhesion, which is consisted of polyacrylamide (PAM) hydrogel framework and polyacrylic acid-functionalized (PAA) with ferrocene (Fc). Morphology, adhesion and pressure resistance of PAAM hydrogel were confirmed by using scanning electron microscope (SEM) and universal testing machine, and Fc decoration in the hydrogel network was well demonstrated by using Fourier transform infrared spectroscopy (FT-IR). Ultraviolet-visible spectroscopy (UV-vis) displayed that the Fc-PAAM hydrogel had excellent peroxidase-like activity as well. It not only exhibited prominent antimicrobial activity against Gram (+/-) bacteria, but also performed high efficiency in preventing the formation of biofilms. In addition, in vivo experiments indicated that this adhesive dressing could significantly prevent bacterial infections. Compared with other clinical treatment methods, this kind of hydrogel is not easy to cause bacterial resistance, and the used raw materials are easy to obtain and low in price, which can amplify the antibacterial properties of H2O2 and provide a new opportunity for the treatment of clinical bacterial infections.

Targeting effect of berberine on type I fimbriae of Salmonella Typhimurium and its effective inhibition of biofilm.

As a primary cause of food contamination and human diseases, Salmonella Typhimurium can easily form a biofilm that is difficult to remove from food surfaces, and often causes significant invisible threats to food safety. Although berberine has been widely used as an anti-infective drug in traditional medicine, some basic principles underlying its mechanism, especially the interaction between berberine and type I fimbriae genes, has not been verified yet. In this study, two strains of major fimbrial gene mutants (ΔfimA and ΔfimH) were constructed to demonstrate the possible action of berberine on type I fimbriae genes. The broth microdilution method was used to determine the antibacterial activity of berberine against selected strains (WT, ΔfimA, and ΔfimH). Cell agglutination experiments revealed that the number of S. Typhimurium type I fimbriae reduced after berberine treatment, which was consistent with transmission electron microscopy results. Quantitative real-time PCR experiments also confirmed that berberine reduced fimA gene expression, indicating a certain interaction between berberine and fimA gene. Furthermore, confocal laser scanning microscopy imaging of biofilm clearly revealed that berberine prevents biofilm formation by reducing the number of type I fimbriae. Overall, it is well speculated for us that berberine could be an excellent combating-biofilm drug in clinical microbiology and food preservation. KEY POINTS: • Reduce the number of fimbriae. • Berberine targeting fimA. • Effective biofilm inhibitor.

Flagellar Motility Is Critical for Salmonella enterica Serovar Typhimurium Biofilm Development.

The food-borne pathogen Salmonella enterica serovar Typhimurium (S. Typhimurium) causes self-limiting gastroenteritis in humans and is not easily eradicated because it often attaches to suitable surfaces to form biofilms that have high resistance to disinfectants and antimicrobials. To develop an alternative strategy for the treatment of biofilms, it is necessary to further explore the effects of flagellar motility on the development process of Salmonella biofilms. Here, we constructed flagella mutants (ΔflgE and ΔfliC) to systematically study this process. By comparing them with wild-type strains, we found that these mutants lacking flagellar motility form fewer biofilms in the early stage, and the formed mature biofilms contain more cells and extracellular polymeric substances (EPS). In addition, fewer mutant cells adhered to glass plates compared with wild-type cells even after 6 h of incubation, suggesting that flagellar motility plays a significant role in preliminary cell-surface interactions. More importantly, the motility of wild-type strain was greatly decreased when they were treated with carbonyl cyanide m-chlorophenylhydrazone, which inhibited flagellar motility and reduced biofilm formation, as in the case of the ΔflgE mutant. Overall, these findings suggest that flagellar motility plays an important role in Salmonella biofilm initiation and maturation, which can help us to counteract the mechanisms involved in biofilm formation and to develop more rational control strategies.

G-quadruplex-based assay combined with aptamer and gold nanoparticles for Escherichia coli K88 determination.

A colorimetric method was developed using G-quadruplex and gold nanoparticles (AuNPs) for determination of Escherichia coli K88 (ETEC K88). It was composed of two modules: (1) an aptamer as biorecognizing element and (2) a capturing DNA (modified with AuNPs at 5') as a transducer. In the absence of target bacteria, the aptamer can form stable double strands with capturing DNA, preventing the binding of capturing DNA to the G-quadruplex. However, the double strands of capturing DNA and aptamer are untied due to the stronger binding of aptamers to bacteria in the presence of target bacteria. As a result, the G-quadruplex binds to capture DNA and leads to the aggregation and color change of AuNPs, which can be monitored by a spectrophotometer or visualization. The quantitative determination was achieved by monitoring the optical density change of AuNPs solution at 524 nm after target addition. Under optimal conditions, the method has a low detection limit (1.35 × 102 CFU mL-1) and a linear response in the range 102 to 106 CFU mL-1. Graphical abstract The manuscripts describe a colorimetric method for the detection of ETEC K88 by using intermolecular G-quadruplex to induce the agglomeration of gold nanoparticles, which can be directly used to determine the presence of bacteria with our naked eyes.