Pathogenic bacteria have become a huge threat to social health and economy for their frighteningly infectious and lethal capacity. It is quite important to make a diagnosis in advance to prevent ...infection or allow a rapid treatment after infection. Noble metal nanoparticles, due to their unique physicochemical properties, especially optical properties, have drawn a great attention during the past decades and have been widely applied into all kinds of fields related to human health. By utilizing these noble metal nanoparticles, optical diagnosis platforms towards pathogenic bacteria have emerged continually, providing highly sensitive, selective, and particularly facile detection tools for clinic or point-of-care diagnosis. This review summarizes the recent development in this field. It begins with a brief introduction of pathogenic bacteria and noble metal nanoparticles. And then, optical detection methods are systematically discussed in three distinct aspects. In addition to these proof-of-concept methods, corresponding algorithms and point-of-care detection devices are also described. Finally, the review ends up with subjective views on present limitations and some appropriate advice for future research directions.
Graphical abstract
Photoredox-neutral hydroxyalkylations of quinolines with aldehydes, induced by sustainable visible light under mild conditions, are described. Non-toxic and inexpensive LiBr is found to be the key ...for the success of the atom-economical Minisci method. Combined with a highly oxidative photocatalyst and visible light irradiation, the bromide additive mediates the H abstraction/acyl radical formation directly from aldehydes. The present mild photoredox neutral protocol provides an important alternative, especially for the challenging Minisci hydroalkylations, as well as a promising approach for atom-economical Minisci reactions with broader N-heterocycle spectra.
A bromide additive is found to be the key for the success of atom-economical photoredox neutral Minisci hydroxyalkylations.
Exosomal microRNAs (miRNAs) have been suggested to participate in the pathogenesis of neuropsychiatric diseases, but their role in major depressive disorder (MDD) is unknown. We performed a ...genome-wide miRNA expression profiling of blood-derived exosomes from MDD patients and control subjects and revealed the top differentially expressed exosomal miRNA, i.e. hsa-miR-139-5p (upregulation), had good performance to differentiate between MDD patients and controls. Tail vein injection of blood exosomes isolated from MDD patients into normal mice caused their depressive-like behaviors as determined by the forced swimming, tail suspension, and novelty suppressed feeding tests, and injection of blood exosomes isolated from healthy volunteers into unpredictable mild stress (CUMS)-treated mice alleviated their depressive-like behaviors. CUMS mice also showed significantly increased blood and brain levels of exosomal miR-139-5p. Furthermore, the depressive-like behaviors in CUMS-treated mice were rescued by intranasal injection of miR-139-5p antagomir, suggesting that increased exosomal miR-139-5p levels may mediate stress-induced depression-like behavior in mice. Both exosome treatment and miR-139-5p antagomir treatment increased hippocampal neurogenesis in the CUMS-treated mice, and treatment of exosome from MDD patients decreased hippocampal neurogenesis in the normal mice. The role of miR-139-5p in neurogenesis was validated by in vitro experiments, demonstrating that miR-139-5p is a negative regulator for neural stem cell proliferation and neuronal differentiation. Our findings together suggest that exosomes from patients with major depression caused depressive-like behaviors in mice with involvement of miR-139-5p-regulated neurogenesis. Therefore, exosomal miRNAs are promising targets for the diagnosis and treatment of MDD.
Radical addition is a robust tool for bond formation. While ketyl radical reactivity of aldehydes by photoredox has been well-established, herein, we have now revealed a pathway for umpolung addition ...of aldehydes with or without external reductant. Hence, the reductive alkylations and challenging benzylations of nitrogen heteroarenes (i.e., Minisci reactions) are enabled by the bromide-promoted visible light-mediated photocatalysis. The present protocol offers a mild, viable method for late-stage alkylations and transition-metal-free benzylations of biologically active nitrogen-heteroarene molecules. Mechanistic studies are indicative of a bromide-initiated acyl radical mechanism in the absence of external reductant.
Migratory birds play an important role in the spread of multidrug-resistant (MDR) bacteria. To investigate the prevalence of MDR Escherichia coli in migratory birds in China and potential ...relationships with the environment, a total of 1387 samples (fecal samples, cloacal swabs, or throat swabs) were collected from migratory birds from three different river basins in China. The collected samples were processed and subjected to bacteriological examinations. Antimicrobial susceptibility testing of the recovered isolates was performed using the E-test for the detection of minimum inhibitory concentrations (MICs). Some antibiotic resistance genes were detected and the PCR products were confirmed by sequencing. In total, 478 (34.7%) E. coli isolates were recovered. The results showed that the drug-resistant E. coli isolates were highly resistant to β-lactams (43.7%) and tetracycline (22.6%), and 73 (15.3%) were MDR, including eight that were extended spectrum β-lactamase-positive. The retrieved strains harbored the blaCTX-M, blaTEM-1, tet(A), tet(B), tet(M), sul1, sul2, sul3, cmlA, floR, and intI1 genes with a prevalence of 5.9%, 36.4%, 80.5%, 11.9%, 6.8%, 6.8%, 47.5%, 12.7%, 50.8%, 37.3%, and 61.0%, respectively. The drug resistance rate of the isolates from southern China was higher than those from northern China. The E. coli samples collected for migratory birds in the Pearl River Basin had the highest proportion (46.7%) MDR isolates. Furthermore, MDR bacteria carried by migratory birds were closely related to the antibiotic content in the basin, which confirms that MDR bacteria carried by migratory birds are likely acquired from the environment. This study also confirmed that migratory birds are potential transmitters of MDR bacteria, demonstrating the need to reduce the use and emission of antibiotics and further in-depth studies on the mechanisms underlying drug resistance of bacteria.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
High-entropy ceramics attract more and more attention in recent years. However, mechanical properties especially strength and fracture toughness for high-entropy ceramics and their composites have ...not been comprehensively reported. In this work, high-entropy (Ti
0.2
Zr
0.2
Hf
0.2
Nb
0.2
Ta
0.2
)B
2
(HEB) monolithic and its composite containing 20 vol% SiC (HEB–20SiC) are prepared by hot pressing. The addition of SiC not only accelerates the densification process but also refines the microstructure of HEB, resulting in improved mechanical properties. The obtained dense HEB and HEB–20SiC ceramics hot pressed at 1800 ℃ exhibit four-point flexural strength of 339±17 MPa and 447±45 MPa, and fracture toughness of 3.81±0.40 MPa·m
1/2
and 4.85±0.33 MPa·m
1/2
measured by single-edge notched beam (SENB) technique. Crack deflection and branching by SiC particles is considered to be the main toughening mechanisms for the HEB–20SiC composite. The hardness
Hv
0.2
of the sintered HEB and HEB–20SiC ceramics is 23.7±0.7 GPa and 24.8±1.2 GPa, respectively. With the increase of indentation load, the hardness of the sintered ceramics decreases rapidly until the load reaches about 49 N, due to the indentation size effect. Based on the current experimental investigation it can be seen that the room temperature bending strength and fracture toughness of the high-entropy diboride ceramics are within ranges commonly observed in structure ceramics.
Tumor exosomes that inherit molecular markers from their parent cells are emerging as cellular “surrogates” in cancer diagnostics. Molecular profiling and detection of exosomes offer a noninvasive ...access to the state of cancer progression, yet are still technically challenging. Here we report an exosome-oriented, aptamer nanoprobe-based profiling (ExoAPP) assay to phenotype surface proteins and quantify cancerous exosomes in a facile mix-and-detect format. Our ExoAPP interfaces graphene oxide (GO) with target-responsive aptamers to profile exosomal markers across five cell types by complementing with enzyme-assisted exosome recycling, revealing a heterogeneous pattern.This assay achieves a detection limit down to 1.6 × 105 particles/mL, lowered by several orders of magnitude over other homogeneous protocols. Such a sensitive ExoAPP assay allows for monitoring epithelial-mesenchymal transition through heterogeneous exosomes without involving cellular internalization that often occurs in GO-based cargo delivery. Using ExoAPP to analyze blood samples from prostate cancer patients, we find that target exosome can be identified by surface PSMA, suggesting their potential in clinical diagnosis.
Hepatitis B virus (HBV) can integrate into the human genome, contributing to genomic instability and hepatocarcinogenesis. Here by conducting high-throughput viral integration detection and RNA ...sequencing, we identify 4,225 HBV integration events in tumour and adjacent non-tumour samples from 426 patients with HCC. We show that HBV is prone to integrate into rare fragile sites and functional genomic regions including CpG islands. We observe a distinct pattern in the preferential sites of HBV integration between tumour and non-tumour tissues. HBV insertional sites are significantly enriched in the proximity of telomeres in tumours. Recurrent HBV target genes are identified with few that overlap. The overall HBV integration frequency is much higher in tumour genomes of males than in females, with a significant enrichment of integration into chromosome 17. Furthermore, a cirrhosis-dependent HBV integration pattern is observed, affecting distinct targeted genes. Our data suggest that HBV integration has a high potential to drive oncogenic transformation.
The 18 kDa translocator protein (TSPO), previously known as the peripheral benzodiazepine receptor, is expressed in the injured brain. It has become known as an imaging marker of “neuroinflammation” ...indicating active disease, and is best interpreted as a nondiagnostic biomarker and disease staging tool that refers to histopathology rather than disease etiology. The therapeutic potential of TSPO as a drug target is mostly based on the understanding that it is an outer mitochondrial membrane protein required for the translocation of cholesterol, which thus regulates the rate of steroid synthesis. This pivotal role together with the evolutionary conservation of TSPO has underpinned the belief that any loss or mutation of TSPO should be associated with significant physiological deficits or be outright incompatible with life. However, against prediction, full Tspo knockout mice are viable and across their lifespan do not show the phenotype expected if cholesterol transport and steroid synthesis were significantly impaired. Thus, the “translocation” function of TSPO remains to be better substantiated. Here, we discuss the literature before and after the introduction of the new nomenclature for TSPO and review some of the newer findings. In light of the controversy surrounding the function of TSPO, we emphasize the continued importance of identifying compounds with confirmed selectivity and suggest that TSPO expression is analyzed within specific disease contexts rather than merely equated with the reified concept of “neuroinflammation.”
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•ZVI–persulfate conditioning could improve ADS dewaterability.•CST of ADS with ZVI–persulfate conditioning was reduced by 90%.•ZVI–persulfate conditioning is economically favorable.
...Biological wastewater treatment process generates large amounts of sludge, the treatment and disposal of which incur substantial costs. Enhancement of sludge dewaterability is of great importance for decreasing the sludge disposal cost in a wastewater treatment plant (WWTP). This study proposes an innovative conditioning approach to improve the dewaterability of the anaerobically digested sludge (ADS) collected from a full-scale WWTP for the first time. The ADS dewaterability was significantly improved in the presence of persulfate (0–1.0g/g TS; TS: total solids) and zero valent iron (ZVI) (0–4.0g/g TS) at neutral pH. The largest improvement of ADS dewaterability was obtained at 2.0g ZVI/g TS and 0.5g persulfate/g TS, under which the capillary suction time (an indicator of sludge dewaterability) was decreased by approximately 90%. Compared with the traditional Fenton process (Fe2++H2O2 at pH 2.0), economic analysis indicated that the ZVI–persulfate conditioning process is more economically attractive for enhancing ADS dewaterability.
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