Elongatibacter sediminis gen. nov., sp. nov., isolated from intertidal sediment, and genomic comparison with all genera in the family Wenzhouxiangellaceae.

A novel slightly halophilic, aerobic, and Gram-stain-negative strain, designated as CH-27T, was isolated during a bacterial resource investigation of intertidal sediment collected from Xiaoshi Island in Weihai, PR China. Cells of strain CH-27T were rod-shaped with widths of 0.3-0.6 µm and lengths of 2.0-11.0 µm. Strain CH-27T grew optimally at 37 °C, pH 7.0 and with 2.0 % (w/v) NaCl. Catalase activity was weakly positive and oxidase activity was positive. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain CH-27T was most related to Marinihelvus fidelis KCTC 92639T (93.6 %), followed by Wenzhouxiangella marina MCCC 1K00261T (92.0 %). Based on genome comparisons between strain CH-27T and M. fidelis KCTC 92639T, the average amino acid identity was 63.6 % and the percentage of conserved proteins was 48.3 %. The major cellular fatty acid of strain CH-27T (≥10 %) was iso-C15 : 0 and the sole respiratory quinone was quinone-8. The polar lipids were phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, and aminophospholipid. The DNA G+C content was 62.7 mol%. Based on comprehensive analysis of its phylogenetic, physiological, biochemical, and chemotaxonomic characteristics, strain CH-27T represents a novel species in a novel genus, for which the name Elongatibacter sediminis gen. nov., sp.nov. is proposed. The type strain is CH-27T (=MCCC 1H00480T=KCTC 8011T).

Long-term associations of PM1 versus PM2.5 and PM10 with asthma and asthma-related respiratory symptoms in the middle-aged and elderly population.

Background: Few studies have compared the associations between long-term exposures to particulate matters (aerodynamic diameter ≤1, ≤2.5 and ≤10 µm: PM1, PM2.5 and PM10, respectively) and asthma and asthma-related respiratory symptoms. The objective of the present study was to compare the strength of the aforementioned associations in middle-aged and elderly adults. Methods: We calculated the mean 722-day personal exposure estimates of PM1, PM2.5 and PM10 at 1 km×1 km spatial resolution between 2013 and 2019 at individual levels from China High Air Pollutants (CHAP) datasets. Using logistic regression models, we presented the associations as odds ratios and 95% confidence intervals, for each interquartile range (IQR) increase in PM1/PM2.5/PM10 concentration. Asthma denoted a self-reported history of physician-diagnosed asthma or wheezing in the preceding 12 months. Results: We included 7371 participants in COPD surveillance from Guangdong, China. Each IQR increase in PM1, PM2.5 and PM10 was associated with a greater odds (OR (95% CI)) of asthma (PM1: 1.22 (1.02-1.45); PM2.5: 1.24 (1.04-1.48); PM10: 1.30 (1.07-1.57)), wheeze (PM1: 1.27 (1.11-1.44); PM2.5: 1.30 (1.14-1.48); PM10: 1.34 (1.17-1.55)), persistent cough (PM1: 1.33 (1.06-1.66); PM2.5: 1.36 (1.09-1.71); PM10: 1.31 (1.02-1.68)) and dyspnoea (PM1: 2.10 (1.84-2.41); PM2.5: 2.17 (1.90-2.48); PM10: 2.29 (1.96-2.66)). Sensitivity analysis results were robust after excluding individuals with a family history of allergy. Associations of PM1, PM2.5 and PM10 with asthma and asthma-related respiratory symptoms were slightly stronger in males. Conclusion: Long-term exposure to PM is associated with increased risks of asthma and asthma-related respiratory symptoms.

Gapr for large-scale collaborative single-neuron reconstruction.

Whole-brain analysis of single-neuron morphology is crucial for unraveling the complex structure of the brain. However, large-scale neuron reconstruction from terabyte and even petabyte data of mammalian brains generated by state-of-the-art light microscopy is a daunting task. Here, we developed 'Gapr' (Gapr accelerates projectome reconstruction) that streamlines deep learning-based automatic reconstruction, 'automatic proofreading' that reduces human workloads at high-confidence sites, and high-throughput collaborative proofreading by crowd users through the Internet. Furthermore, Gapr offers a seamless user interface that ensures high proofreading speed per annotator, on-demand conversion for handling large datasets, flexible workflows tailored to diverse datasets and rigorous error tracking for quality control. Finally, we demonstrated Gapr's efficacy by reconstructing over 4,000 neurons in mouse brains, revealing the morphological diversity in cortical interneurons and hypothalamic neurons. Here, we present Gapr as a solution for large-scale single-neuron reconstruction projects.

Enhancement of endothelial function and attenuation of portal vein injury using mesenchymal stem cells carrying miRNA-25-3p.

The aims of this study were to determine whether human umbilical cord mesenchymal stem cells (hucMSCs) modified by miRNA-25-3p (miR-25-3p) overexpression could promote venous endothelial cell proliferation and attenuate portal endothelial cell injury. HucMSCs and human umbilical vein endothelial cells (HUVEC) were isolated and cultured from human umbilical cord and characterized. Lentiviral vectors expressing miRNA-25-3p were transfected into hucMSCs and confirmed by PCR. We verified the effect of miR-25-3p-modified hucMSCs on HUVEC by cell co-culture and cell supernatant experiments. Subsequently, exosomes of miR-25-3p-modified hucMSCs were isolated from cell culture supernatants and characterized by WB, NTA and TEM. We verified the effects of miR-25-3p-modified exosomes derived from hucMSCs on HUVEC proliferation, migration, and angiogenesis by in vitro cellular function experiments. Meanwhile, we further examined the downstream target genes and signaling pathways potentially affected by miR-25-3p-modified hucMSC-derived exosomes in HUVEC. Finally, we established a rat portal vein venous thrombosis model by injecting CM-DiR-labeled hucMSCs intravenously into rats and examining the homing of cells in the portal vein by fluorescence microscopy. Histological and immunohistochemical experiments were used to examine the effects of miRNA-25-3p-modified hucMSCs on the proliferation and damage of portal vein endothelial cells. Primary hucMSCs and HUVECs were successfully isolated, cultured and characterized. Primary hucMSCs were modified with a lentiviral vector carrying miR-25-3p at MOI 80. Co-culture and cell supernatant intervention experiments showed that overexpression of miRNA-25-3p in hucMSCs enhanced HUVEC proliferation, migration and tube formation in vitro. We successfully isolated and characterized exosomes of miR-25-3p-modified hucMSCs, and exosome intervention experiments demonstrated that miR-25-3p-modified exosomes derived from hucMSCs similarly enhanced the proliferation, migration, and angiogenesis of HUVECs. Subsequent PCR and WB analyses indicated PTEN/KLF4/AKT/ERK1/2 as potential pathways of action. Analysis in a rat portal vein thrombosis model showed that miR-25-3p-modified hucMSCs could homing to damaged portal veins. Subsequent histological and immunohistochemical examinations demonstrated that intervention with miR-25-3p overexpression-modified hucMSCs significantly reduced damage and attenuated thrombosis in rat portal veins. The above findings indicate suggest that hucMSCs based on miR-25-3p modification may be a promising therapeutic approach for use in venous thrombotic diseases.

Association between tobacco smoke exposure and depression: the NHANES 2005-2018 and Mendelian randomization study.

OBJECTIVE: The relationship between tobacco smoke exposure (TSE) and depression is controversial. This study combined observational research and Mendelian randomization (MR) to explore the relationship of depression with both smoking status and cotinine levels. METHOD: We collected relevant data from the National Health and Nutrition Examination Survey (NHANES) database from 2005 to 2018, and used weighted multifactorial logistic regression modelling to assess the correlation between TSE and depression, and assessed the causal relationship of depression with both smoking status and cotinine levels by MR. RESULT: Current smokers had the highest risk of depression (OR 1.94; P < 0.01); there was a positive trend for correlation between daily smoking and depression (OR 1.66; P for trend < 0.01). Serum ketamine levels above 3.00 ng/ml had a higher risk of depression (OR 2.13; P < 0.001). MR results showed that current smoking (OR = 4.66; P < 0.001) and previous smoking (OR 2.09; P < 0.01) were risk factors for the onset of depression, and that there was no causal association between cotinine levels and depression. CONCLUSION: Smoking is significantly associated with depression and plays a potential causal role in the development of depression. Cotinine was significantly associated with depression, however MR results showed no causal relationship between cotinine and depression.

Assessment of the influence of levees along Yangtze River on Oncomelania hupensis, the intermediate host of Schistosoma japonicum.

BACKGROUND: Oncomelania hupensis is the exclusive intermediate host of Schistosoma japonicum in China. Snail control is an essential component of schistosomiasis elimination programme. With 70 years of continuous efforts, the range of O. hupensis had reduced significantly, but slowed down in last decades. A large number of levees against flooding were constructed along Yangtze River and its affiliated lakes in the middle and lower reaches, which influenced the hydrology and ecology in the alluvial plains. The purpose of this study was to assess the impact of levees on the distribution of O. hupensis in the middle and lower reaches of the Yangtze River. METHODS: The snail habitats were digitalised by hand-held GPS system. The years for discovery and elimination of snail habitats were extracted from historical records. The accumulated snail-infested range for each habitat was calculated on the basis of annual reports. The current distribution of O. hupensis was determined by systematic and environmental sampling. The geographical distribution of levees was obtained from satellite imagery. To assess the impact of levees, the data pertaining to O. hupensis were divided into two parts: inside and outside the Yangtze River. Joinpoint regression was utilised to divide the study time span and further characterise the regression in each period. The 5-year-period moving averages of eliminated area infested by snails were calculated for the habitats inside and outside Yangtze River. The moving routes of corresponding geographical median centres were simulated in ArcGIS. Hotspot analysis was used to determine the areas with statistical significance clustering of O. hupensis density. RESULTS: Three periods were identified according to Joinpoint regression both inside and outside Yangtze River. The area infested by O. hupensis increased in the first two periods. It decreased rapidly outside Yangtze River year over year after 1970, while that inside the Yangtze River did not change significantly. Furthermore, the latter was significantly higher than the former. It was observed that the present density of O. hupensis inside Yangtze River was lower than outside the Yangtze River. The median centre for eliminated ranges inside Yangtze River wavered between the east (lower reach) and the west (middle reach). In contrast, the median centre for eliminated ranges continuously moved from the east to the west. CONCLUSIONS: Our findings indicated that the levees had a considerable negative impact on the distribution of O. hupensis outside Yangtze River. Some hotspots observed in the irrigation areas need a sluice system at the inlet of branch for snail control. The major distribution of O. hupensis located in Hubei might be caused by severe waterlogging. The intensive surveillance should be implemented there. The biggest two freshwater lakes, the major endemic regions historically, were identified as cold spots. The long-term impact of Three Gorges Dam on the distribution of O. hupensis in the lakes should be monitored and evaluated.

Determination of 16 ultraviolet-absorbing compounds in marine invertebrates by using LC-USI-MS/MS coupled with QuEChERS.

In this study, we examined multiple endocrine-disrupting ultraviolet-absorbing compounds (UVACs) in marine invertebrates used in personal care products and packaging. Modified QuEChERS and liquid chromatography UniSpray ionization tandem mass spectrometry were used to identify 16 UVACs in marine invertebrates. Matrix-matched calibration curves revealed high linearity (r ≥ 0.9929), with limits of detection and quantification of 0.006-1.000 and 0.020-3.000 ng/g w.w., respectively. In oysters, intraday and interday analyses revealed acceptable accuracy (93%-120%) and precision (≤18%), except for benzophenone (BP) and ethylhexyl 4-(dimethylamino) benzoate. Analysis of 100 marine invertebrate samples revealed detection frequencies of 100%, 98%, 89%, 64%, and 100% for BP, 4-hydroxybenzophenone, 4-methylbenzophenone, 4-methylbenzylidene camphor, and benzophenone-3 (BP-3), respectively. BP and BP-3 were detected at concentrations of 4.40-27.39 and < 0.020-0.560 ng/g w.w., respectively, indicating their widespread presence. Overall, our proposed method successfully detected UVACs in marine invertebrates, raising concerns regarding their potential environmental and health effects.

Electroacupuncture Alleviates Memory Deficits in APP/PS1 Mice by Targeting Serotonergic Neurons in Dorsal Raphe Nucleus.

OBJECTIVE: Alzheimer's disease (AD) has become a significant global concern, but effective drugs able to slow down AD progression is still lacked. Electroacupuncture (EA) has been demonstrated to ameliorate cognitive impairment in individuals with AD. However, the underlying mechanisms remains poorly understood. This study aimed at examining the neuroprotective properties of EA and its potential mechanism of action against AD. METHODS: APP/PS1 transgenic mice were employed to evaluate the protective effects of EA on Shenshu (BL 23) and Baihui (GV 20). Chemogenetic manipulation was used to activate or inhibit serotonergic neurons within the dorsal raphe nucleus (DRN). Learning and memory abilities were assessed by the novel object recognition and Morris water maze tests. Golgi staining, western blot, and immunostaining were utilized to determine EA-induced neuroprotection. RESULTS: EA at Shenshu (BL 23) and Baihui (GV 20) effectively ameliorated learning and memory impairments in APP/PS1 mice. EA attenuated dendritic spine loss, increased the expression levels of PSD95, synaptophysin, and brain-derived neurotrophic factor in hippocampus. Activation of serotonergic neurons within the DRN can ameliorate cognitive deficits in AD by activating glutamatergic neurons mediated by 5-HT1B. Chemogenetic inhibition of serotonergic neurons in the DRN reversed the effects of EA on synaptic plasticity and memory. CONCLUSION: EA can alleviate cognitive dysfunction in APP/PS1 mice by activating serotonergic neurons in the DRN. Further study is necessary to better understand how the serotonergic neurons-related neural circuits involves in EA-induced memory improvement in AD.

Research on a Recognition Algorithm for Traffic Signs in Foggy Environments Based on Image Defogging and Transformer.

The efficient and accurate identification of traffic signs is crucial to the safety and reliability of active driving assistance and driverless vehicles. However, the accurate detection of traffic signs under extreme cases remains challenging. Aiming at the problems of missing detection and false detection in traffic sign recognition in fog traffic scenes, this paper proposes a recognition algorithm for traffic signs based on pix2pixHD+YOLOv5-T. Firstly, the defogging model is generated by training the pix2pixHD network to meet the advanced visual task. Secondly, in order to better match the defogging algorithm with the target detection algorithm, the algorithm YOLOv5-Transformer is proposed by introducing a transformer module into the backbone of YOLOv5. Finally, the defogging algorithm pix2pixHD is combined with the improved YOLOv5 detection algorithm to complete the recognition of traffic signs in foggy environments. Comparative experiments proved that the traffic sign recognition algorithm proposed in this paper can effectively reduce the impact of a foggy environment on traffic sign recognition. Compared with the YOLOv5-T and YOLOv5 algorithms in moderate fog environments, the overall improvement of this algorithm is achieved. The precision of traffic sign recognition of the algorithm in the fog traffic scene reached 78.5%, the recall rate was 72.2%, and mAP@0.5 was 82.8%.

Chirally Selective and Switchable Luminescence from Achiral Quantum Emitters on Suspended Twisted Stacking Metasurfaces.

Dynamic control of circularly polarized photoluminescence has aroused great interest in quantum optics and nanophotonics. Chiral plasmonic metasurfaces enable the manipulation of the polarization state via plasmon-photon coupling. However, current plasmonic light-emitting metasurfaces for effective deterministic modulation of spin-dependent emission at near-infrared wavelengths are underexplored in terms of dissymmetry and tunability. Here, we demonstrate a microfluidic hybrid emitting system of a suspended twisted stacking metasurface coated with PbS quantum dots. The suspended metasurface is fabricated with a single step of electron beam exposure, exhibiting a strong optical chirality of 309° µm-1 with a thickness of less than λ/10 at key spectral locations. With significant chiral-selective interactions, enhanced photoluminescence is achieved with strong dissymmetry in circular polarization. The dissymmetry factor of the induced circularly polarized emission can reach 1.54. More importantly, altering the refractive index of the surrounding medium at the bottom surface of the metasurface can effectively manipulate the chiroptical responses of the hybrid system, hence leading to chirality-reversed emission. This active hybrid emitting system could be a resultful platform for chirality-switchable light emission from achiral quantum emitters, holding great potential for anticounterfeiting, biosensing, light sources, imaging, and displays.

CRISPR/Cas12a-triggered ordered concatemeric DNA probes signal-on/off multifunctional analytical sensing system for ultrasensitive detection of thalassemia.

Based on CRISPR/Cas12a triggered ordered concatemeric DNA probes, a "on/off" self-powered biosensor is developed to achieve highly sensitive detection of thalassemia gene CD142 through open-circuit potential-assisted visual signal output. The ingeniously constructed glucose oxidase (GOD)-functionalized ordered concatemeric DNA probe structure can significantly amplify signal output, while the coupled CRISPR/Cas12a system is served as a "signal switch" with excellent signal-transducing capabilities. When the ordered concatemeric DNA probe structure is anchored on electrode, the response signal of the sensing system is in the "signal on" mode. While, the presence of the target activates the non-specific cleavage activity of the CRISPR/Cas12a system, causing the sensing system to switch to the "signal off" mode. In the detection system, GOD catalyzes the oxidation of glucose to produce hydrogen peroxide, which further catalyzes the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to form a color product, enabling visual signal of the target through naked-eye color contrast. By employing a multifunctional analytical mode combining electrochemical and visual signal outputs, accurate determination of the target is achieved, with linear ranges of 0.0001-100 pM, and detection limits of 48.1 aM (S/N = 3). This work provides a reference method for sensitive detection of thalassemia genes and holds great diagnostic potential in biomedical applications.

Apramycin has high in vitro activity against Mycobacterium tuberculosis.

Introduction. Aminoglycoside antibiotics such as amikacin and kanamycin are important components in the treatment of Mycobacterium tuberculosis (Mtb) infection. However, more and more clinical strains are found to be aminoglycoside antibiotic-resistant. Apramycin is another kind of aminoglycoside antibiotic that is commonly used to treat infections in animals.Hypothesis. Apramycin may have in vitro activity against Mtb.Aim. This study aims to evaluate the efficacy of apramycin against Mtb in vitro and determine its epidemiological cut-off (ECOFF) value.Methodology. One hundred Mtb isolates, including 17 pansusceptible and 83 drug-resistant tuberculosis (DR-TB) strains, were analysed for apramycin resistance using the MIC assay.Results. Apramycin exhibited significant inhibitory activity against Mtb clinical isolates, with an MIC50 of 0.5 µg ml-1 and an MIC90 of 1 µg ml-1. We determined the tentative ECOFF value as 1 µg ml-1 for apramycin. The resistant rates of multidrug-resistant tuberculosis (MDR-TB), pre-extensively drug-resistant (pre-XDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) strains were 12.12 % (4/33), 20.69 % (6/29) and 66.67 % (14/21), respectively. The rrs gene A1401G is associated with apramycin resistance, as well as the cross-resistance between apramycin and other aminoglycosides.Conclusion. Apramycin shows high in vitro activity against the Mtb clinical isolates, especially the MDR-TB clinical isolates. This encouraging discovery calls for more research on the functions of apramycin in vivo and as a possible antibiotic for the treatment of drug-resistant TB.

Wavelength-tunable high-fidelity entangled photon sources enabled by dual Stark effects.

The construction of a large-scale quantum internet requires quantum repeaters containing multiple entangled photon sources with identical wavelengths. Semiconductor quantum dots can generate entangled photon pairs deterministically with high fidelity. However, realizing wavelength-matched quantum-dot entangled photon sources faces two difficulties: the non-uniformity of emission wavelength and exciton fine-structure splitting induced fidelity reduction. Typically, these two factors are not independently tunable, making it challenging to achieve simultaneous improvement. In this work, we demonstrate wavelength-tunable entangled photon sources based on droplet-etched GaAs quantum dots through the combined use of AC and quantum-confined Stark effects. The emission wavelength can be tuned by ~1 meV while preserving an entanglement fidelity f exceeding 0.955(1) in the entire tuning range. Based on this hybrid tuning scheme, we finally demonstrate multiple wavelength-matched entangled photon sources with f > 0.919(3), paving the way towards robust and scalable on-demand entangled photon sources for quantum internet and integrated quantum optical circuits.

Difficulty in diagnosing intracranial infection caused by Mycobacterium avium in an AIDS patient: case report and review of the literature.

BACKGROUND: Mycobacterium avium complex (MAC) is an uncommon clinical pathogen, especially in the central nervous system (CNS), and carries a poor prognosis. MAC infections commonly present as immune reconstitution disease (IRD) in HIV patients. Herein, we report a case of intracranial infection caused by MAC in an AIDS patient without disseminated MAC (DMAC) and immune reconstitution inflammatory syndrome (IRIS). CASE PRESENTATION: A 31-year-old HIV-positive male presented us with progressively worsening CNS symptoms, and neuroimaging revealed ring-enhancing lesions. The intracranial lesions worsened after the empirical therapy for toxoplasma encephalitis and fungal infection. Due to the rapid progression of the disease, the patient died. Mycobacterium avium was the only pathogen in brain tissue after cultures and molecular biology tests. CONCLUSION: MAC infection in CNS is challenging to diagnose in HIV patients. Our findings emphasize that obtaining tissue samples and applying molecular biology methods is essential to help diagnose the patient as soon as possible to receive adequate treatment.

Efficient Genome Editing with Chimeric Oligonucleotide-Directed Editing.

Prime editing has emerged as a precise and powerful genome editing tool, offering a favorable gene editing profile compared to other Cas9-based approaches. Here we report new nCas9-DNA polymerase fusion proteins to create chimeric oligonucleotide-directed editing (CODE) systems for search-and-replace genome editing. Through successive rounds of engineering, we developed CODEMax and CODEMax(exo+) editors that achieve efficient genome modifications in human cells with low unintended edits. CODEMax and CODEMax(exo+) contain an engineered Bst DNA polymerase derivative known for its robust strand displacement ability. Additionally, CODEMax(exo+) features a 5' to 3' exonuclease activity that promotes effective strand invasion and repair outcomes favoring the incorporation of the desired edit. We demonstrate CODEs can perform small insertions, deletions, and substitutions with improved efficiency compared to PEMax at many loci. Overall, CODEs complement existing prime editors to expand the toolbox for genome manipulations without double-stranded breaks.

Flow-induced fabrication of ZnO nanostructures in pillar-arrayed microchannels.

The emergence of microfluidic devices integrated with nanostructures enables highly efficient, flexible and controllable biosensing, among which zinc oxide (ZnO) nanostructure-based fluorescence detection has been demonstrated to be a promising methodology due to its high electrical point and unique fluorescence enhancement properties. The optimization of microfluidic synthesis of ZnO nanostructures for biosensing on chip has been in demand due to its low cost and high efficiency, but still the flow-induced growth of ZnO nanostructures is not extensively studied. Here, we report a simple and versatile strategy that could manipulate the local flow field by creating periodically arranged micropillars within a straight microchannel. We have explored the effects of perfusion speed and flow direction of seed solution, localized flow variation of growth solution and growth time on the morphology of nanostructures. This provided a comprehensive understanding which governs nanostructure fabrication controlled by flow. The results demonstrated that localized flow in microfluidic devices was essential for the initiation and growth of zinc oxide crystals, enabling precise control over their properties and morphology. Furthermore, a model protein was used to demonstrate the intrinsic fluorescence enhancement of ZnO nanostructures as an example to reveal the morphology-related enhancement properties.

New generation fluoroquinolone sitafloxacin could potentially overcome the majority levofloxacin and moxifloxacin resistance in multidrug-resistant Mycobacterium tuberculosis.

Introduction. Pre-existing fluoroquinolones (FQs) resistance is a major threat in treating multidrug-resistant (MDR) tuberculosis. Sitafloxacin (Sfx) is a new broad-spectrum FQ.Hypothesis. Sfx is more active against drug-resistant Mycobacterium tuberculosis (Mtb) isolates.Aim. To determine whether there is cross-resistance between Sfx and ofloxacin (Ofx), levofloxacin (Lfx) and moxifloxacin (Mfx) in MDR Mtb.Methods. A total of 106 clinical Mtb isolates, including 23 pan-susceptible and 83 MDR strains, were analysed for Sfx, Lfx and Mfx resistance using MIC assay. The isolates were also subjected to whole-genome sequencing to analyse drug-resistant genes.Results. Sfx exhibited the most robust inhibition activity against Mtb clinical isolates, with a MIC50 of 0.0313 µg ml-1 and MIC90 of 0.125 µg ml-1, which was lower than that of Mfx (MIC50 = 0.0625 µg ml-1, MIC90 = 1 µg ml-1) and Lfx (MIC50 = 0.125 µg ml-1, MIC90 = 2 µg ml-1). We determined the tentative epidemiological cut-off values as 0.5 µg ml-1 for Sfx. Also, 8.43% (7/83), 43.37% (36/83), 42.17% (35/83) and 51.81% (43/83) MDR strains were resistant to Sfx, Mfx, Lfx and Ofx, respectively. Cross-resistance between Ofx, Lfx and Mfx was 80.43% (37/46). Only 15.22% (7/46) of the pre-existing FQs resistance isolates were resistant to Sfx. Among the 30 isolates with mutations in gyrA or gyrB, 5 (16.67%) were Sfx resistant. The combination of Sfx and rifampicin could exert partial synergistic effects, and no antagonism between Sfx and six clinically important anti-Mtb antibiotics was evident.Conclusion. Sfx exhibited superior activity against MDR isolates comparing to Lfx and Mfx, and could potentially overcome the majority pre-existing FQs resistance in Mtb strains.

[Spatial-temporal Variations and Driving Factors of Surface Ozone over the Qinghai-Xizang Plateau from 2015 to 2021].

The spatial-temporal distribution pattern of surface O3 over the Qinghai-Xizang Plateau （QXP） was analyzed based on air quality monitoring data and meteorological data from 12 cities on the QXP from 2015 to 2021. Kolmogorov-Zurbenko （KZ） filtering was employed to separate the original O3-8h series into components at different time scales. Then, multiple linear regression of meteorological variables was used to quantitatively isolate the effects of meteorology and emissions. The results revealed that the annual mass concentrations of surface O3-8h from 2015 to 2021 in 12 cities over the QXP ranged from 78.7 to 156.7 µg·m-3, and the exceedance rates of O3 mass concentrations （National Air Quality Standard of grade II） ranged from 0.7%-1.5%. The monthly O3-8h mass concentration displayed a single-peak inverted "V"-shape and a multi-peak "M"-shape. The maximum monthly concentration of O3 occurred in April to July, and valleys occurred in July, September, and December. The short-term, seasonal, and long-term components of O3-8hdecomposed by KZ filtering contributed 29.6%, 51.4%, and 9.1% to the total variance in the original O3 sequence in 12 cities, respectively. From the whole region, the meteorological conditions were unfavorable for O3 reduction on the QXP from 2015 to 2017, which made the long-term component of O3 increase by 0.2-2.1 µg·m-3. The meteorological conditions were favorable for O3-8h reduction from 2018 to 2021, which led to the long-term component of O3-8h decrease by 0.4-1.1 µg·m-3. The meteorological conditions increased the long-term component of O3-8h in Ngari, Lhasa, Naqu, Nyingchi, Qamdo, Haixi, and Xining, with an average contribution of 30.1%. The meteorological conditions decreased the long-term component of O3-8h in Shigatse and Golog, with contributions of 359.0% and 56.5%, respectively. The increase in the long-term component of O3-8h in Ngari, Shigatse, Nagqu, Haixi, and Xining could be due to the rapid decrease in the long-term component of PM2.5 （4.04 µg·ï¼ˆm3·a）-1）.

Tryptophan As a New Member of RNA-Induced Silencing Complexes Prevents Colon Cancer Liver Metastasis.

Essential amino acids (EAA) and microRNAs (miRs) control biological activity of a cell. Whether EAA regulates the activity of miR has never been demonstrated. Here, as proof-of-concept, a tryptophan (Trp, an EAA) complex containing Argonaute 2 (Ago2) and miRs including miR-193a (Trp/Ago2/miR-193a) is identified. Trp binds miR-193a-3p and interacts with Ago2. Trp/Ago2/miR-193a increases miR-193a-3p activity via enhancing Argonaute 2 (Ago2) RNase activity. Other miRs including miR-103 and miR-107 in the Trp complex enhance miR-193a activity by targeting the same genes. Mechanistically, the Trp/Ago2/miR-193a complex interacts with Trp-binding pockets of the PIWI domain of Ago2 to enhance Ago2 mediated miR activity. This newly formed Ago2/Trp/miR-193a-3p complex is more efficient than miR-193a-3p alone in inhibiting the expression of targeted genes and inhibiting colon cancer liver metastasis. The findings show that Trp regulates miR activity through communication with the RNA-induced silencing complexes (RISC), which provides the basis for tryptophan based miR therapy.

Overcoming the Tumor Collagen Barriers: A Multistage Drug Delivery Strategy for DDR1-Mediated Resistant Colorectal Cancer Therapy.

The extracellular matrix (ECM) is critical for drug resistance in colorectal cancer (CRC). The abundant collagen within the ECM significantly influences tumor progression and matrix-mediated drug resistance (MMDR) by binding to discoidin domain receptor 1 (DDR1), but the specific mechanisms by which tumor cells modulate ECM via DDR1 and ultimately regulate TME remain poorly understand. Furthermore, overcoming drug resistance by modulating the tumor ECM remains a challenge in CRC treatment. In this study, a novel mechanism is elucidated by which DDR1 mediates the interactions between tumor cells and collagen, enhances collagen barriers, inhibits immune infiltration, promotes drug efflux, and leads to MMDR in CRC. To address this issue, a multistage drug delivery system carrying DDR1-siRNA and chemotherapeutic agents is employed to disrupt collagen barriers by silencing DDR1 in tumor, enhancing chemotherapy drugs diffusion and facilitating immune infiltration. These findings not only revealed a novel role for collagen-rich matrix mediated by DDR1 in tumor resistance, but also introduced a promising CRC treatment strategy.