Controlling 1D Nanostructures and Handedness by Polar Residue Chirality of Amphiphilic Peptides.

Peptide assemblies are promising nanomaterials, with their properties and technological applications being highly hinged on their supramolecular architectures. Here, how changing the chirality of the terminal charged residues of an amphiphilic hexapeptide sequence Ac-I4 K2 -NH2 gives rise to distinct nanostructures and supramolecular handedness is reported. Microscopic imaging and neutron scattering measurements show thin nanofibrils, thick nanofibrils, and wide nanotubes self-assembled from four stereoisomers. Spectroscopic and solid-state nuclear magnetic resonance (NMR) analyses reveal that these isomeric peptides adopt similar anti-parallel ß-sheet secondary structures. Further theoretical calculations demonstrate that the chiral alterations of the two C-terminal lysine residues cause the formation of diverse single ß-strand conformations, and the final self-assembled nanostructures and handedness are determined by the twisting direction and degree of single ß-strands. This work not only lays a useful foundation for the fabrication of diverse peptide nanostructures by manipulating the chirality of specific residues but also provides a framework for predicting the supramolecular structures and handedness of peptide assemblies from single molecule conformations.

High expression of 3-hydroxy-3-methylglutaryl-CoA synthase 2 (HMGCS2) associated with Diquat-induced damage.

Diquat (DQ) is a commonly used bipyridine herbicide known for its toxic properties and adverse effects on individuals. However, the mechanism underlying DQ-induced damage remain elusive. Our research aimed to uncover the regulatory network involved in DQ-induced damage. We analyzed publicly accessible gene expression patterns and performed research using a DQ-induced damage animal model. The GSE153959 dataset from the Gene Expression Omnibus collection and the animal model of DQ-induced kidney injury were used to identify differentially expressed genes (DEGs). Pathways including the regulation of DNA-templated transcription in response to stress, RNA polymerase II transcription regulator complex and transcription coregulatory activity were shown to be enriched in 21 DEGs. We used least absolute shrinkage and selection operator (LASSO) regression analysis to find possible diagnostic biomarkers for DQ-induced damage. Then, we used an HK-2 cell model to confirm these results. Additionally, we confirmed that 3-hydroxy-3-methylglutaryl-CoA synthase 2 (HMGCS2) was the major gene associated with DQ-induced damage using multi-omics screening. The sample validation strongly suggested that HMGCS2 has promise as a diagnostic marker and may provide new targets for therapy in the context of DQ-induced damage.

Research progress on the regulatory mechanisms of Irisin on cognitive dysfunction in patients with Alzheimer's disease and the interventional role of Irisin in associated diseases.

Irisin, a peptide produced during exercise, is believed to play a role in regulating energy levels within the body. Moreover, Irisin has the ability to traverse the blood-brain barrier and engage in various pathophysiological processes within the central nervous system. An increasing body of research identifies Irisin as a significant therapeutic target for neurodegenerative diseases, indicating a strong link between Irisin and the development of cognitive impairments. In this paper, we present a concise review of effects of different types of exercise on Irisin production, and the mechanisms underlying the Irisin's intervention in various diseases including metabolic diseases, kidney injury and depression. Following this, we delve into an in-depth exploration of its role in modulating cognitive dysfunction among patients with Alzheimer's disease (AD), focusing on recent advancements in three critical areas: neuroinflammation, mitochondrial dysfunction, and protein misfolding. Finally, we put forth 3 hypotheses: (1) exercise-induced fibronectin type III domain containing protein 5 (FNDC5) stimulation and subsequent Irisin cleavage may be associated with the stress response in energy metabolism; (2) Irisin, as a myokine, likely plays a role in mitochondrial repair mechanisms to ameliorate cognitive impairment in AD patients; (3) Irisin is a homeostatic factor that maintains energy homeostasis and is closely related to the dynamic stability of the body's internal environment.

Fingerprint Stimulated Raman Scattering Imaging Unveils Ergosteryl Ester as a Metabolic Signature of Azole-Resistant Candida albicans.

Candida albicans (C. albicans), a major fungal pathogen, causes life-threatening infections in immunocompromised individuals. Fluconazole (FLC) is recommended as first-line therapy for treatment of invasive fungal infections. However, the widespread use of FLC has resulted in increased antifungal resistance among different strains of Candida, especially C. albicans, which is a leading source of hospital-acquired infections. Here, by hyperspectral stimulated Raman scattering imaging of single fungal cells in the fingerprint window and pixel-wise spectral unmixing, we report aberrant ergosteryl ester accumulation in azole-resistant C. albicans compared to azole-susceptible species. This accumulation was a consequence of de novo lipogenesis. Lipid profiling by mass spectroscopy identified ergosterol oleate to be the major species stored in azole-resistant C. albicans. Blocking ergosterol esterification by oleate and suppressing sterol synthesis by FLC synergistically suppressed the viability of C. albicans in vitro and limited the growth of biofilm on mouse skin in vivo. Our findings highlight a metabolic marker and a new therapeutic strategy for targeting azole-resistant C. albicans by interrupting the esterified ergosterol biosynthetic pathway.

Comprehensive Analysis of Universal Stress Protein Family Genes and Their Expression in Fusarium oxysporum Response of Populus davidiana × P. alba var. pyramidalis Louche Based on the Transcriptome.

Universal stress proteins (USPs) are typical stress-inducible proteins that function directly in a variety of biotic or abiotic stresses and effectively protect plants from complex, adverse environments. However, the expression patterns of USP genes under pathogen stress and their molecular mechanisms in stress resistance have not been reported in detail. In this study, 46 USP genes were identified from Populus trichocarpa (PtrUSPs), and their biological characteristics were comprehensively analyzed based on phylogeny, physicochemical properties of proteins, and gene structures. The promoter regions of PtrUSPs contain a variety of cis-acting elements related to hormone and stress response. The results of a collinearity analysis showed that PtsrUSPs were highly conserved with homologous genes from four other representative species (Arabidopsis thaliana, Eucalyptus grandis, Glycine max, and Solanum lycopersicum). Furthermore, RNA-Seq analysis showed that the expression of 46 USPs from P. davidiana × P. alba var. pyramidalis Louche (PdpapUSPs) was significantly induced by Fusarium oxysporum. The co-expression network and gene ontology analysis of PtrUSPs showed that they participated in the response to stress and response to stimulus through precise coordination. The results of this paper systematically revealed the biological characteristics of PtrUSPs and the characteristics of their response to F. oxysporum stress, which will lay a theoretical foundation for improving genetic traits and the breeding of poplar disease-resistant varieties in subsequent studies.

Binaphthyl-Based Chiral Macrocyclic Hosts for the Selective Recognition of Iodide Anions.

In this study, we explorethe synthesis of binaphthyl-based chiral macrocyclic hosts for the first time. They exhibited the selective recognition abilities of iodide anions which can be favored over those of other anions (AcO-, NO3-, ClO4-, HSO4-, Br-, PF6-, H2PO4-, BF4-, and CO3F3S-), as confirmed by UV-vis, HRMS, and 1H NMR spectroscopy experiments, as well as DFT calculations. Neutral aryl C-H···anion interactions play an important role in the formation complexes. The recognition process can be observed by the naked eye.

A Benzothiadiazole-Based Self-Assembled Cage for Cadmium Detection.

A turn-on fluorescent probe, cage 1, was efficiently self-assembled by condensing 4,4'-(benzothiadiazole-4,7-diyl)dibenzaldehyde and TREN in chloroform. The formation of cage 1 was characterized and confirmed by NMR spectroscopy, mass spectrometry, and theoretical calculations. The yield of cage 1 could be controlled by tuning the reaction conditions, such as the precursor concentration. Interestingly, the addition of 10 equiv of Cd2+ relative to cage 1 could increase the fluorescence almost seven-fold. 1H NMR and fluorescence experiments indicating fluorescence enhancement may be caused by the decomposition of cage 1. Such a high selectivity toward Cd2+ implies that the cage could potentially be employed in cadmium detection.

Exploiting the anaerobic fermentation of alfalfa as a renewable source of squalene.

BACKGROUND: The use of alfalfa is a promising response to the increasing demand for squalene. Ensiling could enhance the squalene content of fresh alfalfa and silage. To investigate and exploit the anaerobic fermentation of forage as a new squalene source, alfalfa was ensiled without (CON) or with molasses (ML) and sunflower seed oil (SSL) for 10, 40, and 70 days. RESULTS: Naturally ensiled alfalfa was of poor quality but had up to 1.93 times higher squalene content (P < 0.001) than fresh alfalfa. The squalene-producing bacteria were found to be cocci lactic acid bacteria (LAB). Adding ML and SSL decreased squalene content (P = 0.002 and P < 0.001) by 6.89% and 11.6%, respectively. Multiple linear regression models and correlation analysis indicated that squalene synthase was the key enzyme for squalene synthesis. The addition of ML and SSL altered the structure of LAB communities, mainly decreasing the relative abundance of cocci LAB, which was responsible for squalene synthesis, and changing the fermentation products (lactic acid, propionic acid, and ammonia-N) influencing the squalene-related enzymes, thereby decreasing squalene production. Compared with squalene production from the reference bacteria (Pediococcus acidilactici Ch-2, Rhodopseudomonas palustris, Bacillus subtilis, engineered Escherichia coli), alfalfa silage had the potential to be a new squalene source. CONCLUSION: Natural ensiled alfalfa was a promising source for squalene, and ensiling was a potential pathway to obtain novel high-yield squalene bacteria. © 2022 Society of Chemical Industry.

Evaluation of molasses on fermentation profiles of wheat straw ensiled with tall fescue in the southwest Tibet.

Two experiments were carried out to determine the optimal proportion of mixed silage made with wheat straw and tall fescue, and further to evaluate the effects of molasses on fermentation quality. In Experiment 1, wheat straw and tall fescue were mixed at proportions of 10:0 (Control), 8:2 (WT20), 6:4 (WT40) and 4:6 (WT60) on fresh weight (FW) basis. Inclusion of tall fescue significantly (p < 0.05) increased lactic acid, water-soluble carbohydrate contents and ratio of lactic to acetic acid, and significantly (p < 0.05) decreased pH and contents of dry matter, NH3 -N and volatile fatty acids. WT60 had the highest (p < 0.05) lactic acid content, and the lowest (p < 0.05) pH and butyric acid content. In Experiment 2, the mixture of wheat straw and tall fescue (4/6) were treated with 0%, 3%, 4% and 5% molasses on FW basis (defined as control, WTM3, WTM4 and WTM5 respectively). Molasses addition significantly (p < 0.05) increased lactic acid and water-soluble carbohydrate contents, and significantly (p < 0.05) decreased pH and ammonia-nitrogen content as compared with control. Acetic acid content slightly (p > 0.05) decreased during ensiling, while trace amounts of propionic and butyric acids were observed. WTM5 had the lowest pH and the highest (p < 0.05) lactic acid, water-soluble carbohydrate contents and ratio of lactic to acetic acid at end of ensiling. In conclusion, the fermentation quality was maximally improved when the addition rate of molasses was 5% in 40% wheat straw ensiled with 60% tall fescue.

Effects of wet brewers grains on fermentation quality and in vitro ruminal digestibility of mixed silage prepared with corn stalk, sweet potato peel and dried apple pomace in southeast China.

The effects of wet brewers grains (WBG) on fermentation quality, chemical composition and in vitro ruminal digestibility of mixed silages prepared with corn stalk, dried apple pomace and sweet potato peel were evaluated. A mixture of corn stalk, sweet potato peel and dried apple pomace (50/30/20) was ensiled with 0, 10%, 20% and 30% WBG on a fresh weight (FW) basis for 1, 3, 5, 7, 14 and 30 days respectively. The results showed that the application of WBG increased (p < 0.05) lactic acid, acetic acid and total volatile fatty acids contents, and decreased (p < 0.05) pH, dry matter, water-soluble carbohydrates content and ammonia-nitrogen/total nitrogen during ensiling. The pH in all silages was below 4.03 during ensiling. Treating with WBG increased (p < 0.05) crude protein content, and decreased (p < 0.05) neutral detergent fibre, acid detergent fibre, cellulose and hemicellulose content after 30 days of ensiling. After 72 h of incubation, cumulative gas production, potential gas production and in vitro crude protein digestibility increased (p < 0.05) with the increasing proportions of WBG. However, in vitro digestibility of dry matter and neutral detergent fibre, and metabolisable energy were similar in all silages. The 20% and 30% WBG-treated silages showed better fermentation quality and greater or higher in vitro digestibility, which were indicated by greater or higher (p < 0.05) lactic acid content, in vitro crude protein digestibility, and lower (p < 0.05) pH, ammonia-nitrogen/total nitrogen ratio as compared with the control. Therefore, ensiling agro-food by-products with at least 20% WBG were recommended for improving fermentation quality.

National Canadian Survey on the Management of Noneuploid Embryos.

OBJECTIVE: To comprehensively describe current preimplantation genetic testing for aneuploidy (PGT-A) practices and management of non-euploid embryos in Canada. METHODS: This was a cross-sectional study utilizing an online survey distributed by email to all medical directors of fertility clinics with independent in vitro fertilization (IVF) embryology laboratories. The survey was designed to determine practice patterns regarding PGT-A usage; PGT-A reference laboratory, platform, and thresholds for classifying embryos; and management of embryos classified as mosaic, inconclusive, or aneuploid. RESULTS: Twenty-five medical directors (69%) participated in the survey. The majority of clinics (91%) offered PGT-A screening, with 45% of clinics offering PGT-A as routine screening. The majority of clinics (90%) that offered PGT-A received mosaicism data; 61% of these clinics had transferred mosaic embryos, and 94% would transfer mosaic embryos. Clinics that performed ≥1000 IVF cycles annually were more likely to have transferred mosaic embryos (100% vs. 45.5%; P = 0.043). The mean percentage of IVF cycles using PGT-A was lower in clinics that had transferred mosaic embryos (12.3% vs. 30.4%; P = 0.033). Only 1 clinic had transferred an aneuploid embryo, but 2 other clinics would consider this option. The majority of clinics (61%) that receive mosaicism data would recommend noninvasive prenatal testing (NIPT) following mosaic embryo transfer, with 22% of clinics indicating that this would be the only genetic test offered. CONCLUSION: We report significant practice variation in PGT-A and management of non-euploid embryos across Canada and highlight areas where consensus should be encouraged.

Machine Learning for Evaluating the Cytotoxicity of Mixtures of Nano-TiO2 and Heavy Metals: QSAR Model Apply Random Forest Algorithm after Clustering Analysis.

With the development and application of nanomaterials, their impact on the environment and organisms has attracted attention. As a common nanomaterial, nano-titanium dioxide (nano-TiO2) has adsorption properties to heavy metals in the environment. Quantitative structure-activity relationship (QSAR) is often used to predict the cytotoxicity of a single substance. However, there is little research on the toxicity of interaction between nanomaterials and other substances. In this study, we exposed human renal cortex proximal tubule epithelial (HK-2) cells to mixtures of eight heavy metals with nano-TiO2, measured absorbance values by CCK-8, and calculated cell viability. PLS and two ensemble learning algorithms are used to build multiple QSAR models for data sets, and the test set R2 is increased from 0.38 to 0.78 and 0.85, and RMSE is decreased from 0.18 to 0.12 and 0.10. After selecting the better random forest algorithm, the K-means clustering algorithm is used to continue to optimize the model, increasing the test set R2 to 0.95 and decreasing the RMSE to 0.08 and 0.06. As a reliable machine algorithm, random forest can be used to predict the toxicity of the mixture of nano-metal oxides and heavy metals. The cluster analysis can effectively improve the stability and predictability of the model, and provide a new idea for the prediction of cytotoxicity model in the future.

Assessment of organic acid salts on fermentation quality, aerobic stability, and in vitro rumen digestibility of total mixed ration silage.

The work aimed to investigate the effects of four organic acid salts on fermentation quality, aerobic stability, and in vitro rumen digestibility of total mixed ration (TMR) silage prepared with citric acid residue, wet brewers' grains, and Napier grass. The TMR was ensiled with the following: (1) no additives (control), (2) 0.1% sodium benzoate (SB), (3) 0.1% potassium sorbate (PS), (4) 0.5% sodium diacetate (SDA), (5) 0.5% calcium propionate (CAP) on a fresh weight basis. All silos (10 L) were opened after 60 days of ensiling to determine fermentation profiles and in vitro rumen digestibility, and then were subjected to a 9-day aerobic stability test. Four organic acid salts significantly (p < 0.05) increased dry matter contents, lactic acid bacteria count, and decreased ethanol content and yeast count compared with the control. The SDA and CAP significantly (p < 0.05) increased water-soluble carbohydrates, lactic acid, and crude protein contents, and decreased pH, ammonia nitrogen, neutral detergent fiber, and hemicellulose contents compared with other TMR silages after 60 days of ensiling. Organic acid salts significantly (p < 0.05) prolonged the hours of aerobic stability and significantly (p < 0.05) increased cumulative gas production and potential gas production compared with the control. The treatments of SDA and CAP significantly (p < 0.05) improved aerobic stability as indicated by higher (p < 0.05) lactic acid and water-soluble carbohydrates contents, and lower (p < 0.05) pH, ammonia nitrogen, ethanol contents, and yeast count compared with the control. The treatments of SDA and CAP significantly (p < 0.05) increased in vitro rumen parameters, as indicated by higher (p < 0.05) in vitro digestibility of dry matter, crude protein, and neutral detergent fiber after 60 days of ensiling. Overall, these results indicated that the addition of SDA and CAP could ensure the good fermentation quality and improve aerobic stability of TMR silages. By comprehensive consideration, CAP was recommended for improving fermentation quality, aerobic stability, and in vitro rumen digestibility of TMR silages prepared with wet brewers' grains, citric acid residue, and Napier grass.

Fluorescence-Detected Mid-Infrared Photothermal Microscopy.

Mid-infrared photothermal microscopy is a new chemical imaging technology in which a visible beam senses the photothermal effect induced by a pulsed infrared laser. This technology provides infrared spectroscopic information at submicrometer spatial resolution and enables infrared spectroscopy and imaging of living cells and organisms. Yet, current mid-infrared photothermal imaging sensitivity suffers from a weak dependence of scattering on the temperature, and the image quality is vulnerable to the speckles caused by scattering. Here, we present a novel version of mid-infrared photothermal microscopy in which thermosensitive fluorescent probes are harnessed to sense the mid-infrared photothermal effect. The fluorescence intensity can be modulated at the level of 1% per Kelvin, which is 100 times larger than the modulation of scattering intensity. In addition, fluorescence emission is free of interference, thus much improving the image quality. Moreover, fluorophores can target specific organelles or biomolecules, thus augmenting the specificity of photothermal imaging. Spectral fidelity is confirmed through fingerprinting a single bacterium. Finally, the photobleaching issue is successfully addressed through the development of a wide-field fluorescence-detected mid-infrared photothermal microscope which allows video rate bond-selective imaging of biological specimens.

Identification of chicken-derived scFv against N-glycolylneuraminic acid retrieved from an immune library by phage display.

N- glycolylneuraminic acid (Neu5Gc) is a type of sialic acid, it can be synthesized by a range of mammals except chickens and healthy human. After entering human body, Neu5Gc in foods such as red meat and milk can cause chronic inflammation, thus promoting the development of cancer and related diseases. In this study, we identified a gene sequence of Neu5Gc-specific single-chain variable fragment (ScFv) by phage display from a primary chicken antibodies library. Then the gene sequence was used to express a 29 kDa anti-Neu5Gc ScFv protein as detection probe in competitive inhibition ELISA (IC-ELISA). The linear regression equation of the IC-ELISA was y = 23.12x+33.19 (R = 0.980), and the half-maximal inhibitory concentration (IC50) and the limit of detection (LOD) was 5.333 and 0.66 µg/mL. The mean recovery of the spiked samples was 83.04%, and the intra-assay and inter-assay coefficients of variation (CVs) were both 5.59%. The results suggested that the specific anti-Neu5Gc ScFv is a promising probe for the development of IC-ELISA and test strip in order to detect the presence of Neu5Gc in red meat, milk, and tumor tissues.

Plasmon-enhanced coherent anti-stokes Raman scattering vs plasmon-enhanced stimulated Raman scattering: Comparison of line shape and enhancement factor.

Plasmon-enhanced coherent Raman scattering microscopy has reached single-molecule detection sensitivity. Due to the different driven fields, there are significant differences between a coherent Raman scattering process and its plasmon-enhanced derivative. The commonly accepted line shapes for coherent anti-Stokes Raman scattering and stimulated Raman scattering do not hold for the plasmon-enhanced condition. Here, we present a theoretical model that describes the spectral line shapes in plasmon-enhanced coherent anti-Stokes Raman scattering (PECARS). Experimentally, we measured PECARS and plasmon-enhanced stimulated Raman scattering (PESRS) spectra of 4-mercaptopyridine adsorbed on the self-assembled Au nanoparticle (NP) substrate and aggregated Au NP colloids. The PECARS spectra show a nondispersive line shape, while the PESRS spectra exhibit a dispersive line shape. PECARS shows a higher signal to noise ratio and a larger enhancement factor than PESRS from the same specimen. It is verified that the nonresonant background in PECARS originates from the photoluminescence of nanostructures. The decoupling of background and the vibrational resonance component results in the nondispersive line shape in PECARS. More local electric field enhancements are involved in the PECARS process than in PESRS, which results in a higher enhancement factor in PECARS. The current work provides new insight into the mechanism of plasmon-enhanced coherent Raman scattering and helps to optimize the experimental design for ultrasensitive chemical imaging.

Single-Molecule Level Rare Events Revealed by Dynamic Surface-Enhanced Raman Spectroscopy.

Surface-enhanced Raman spectroscopy (SERS) is a powerful tool to monitor various interfacial behaviors providing molecular level information with high spatial and temporal resolutions. However, it is a challenge to obtain SERS spectra with high quality for analytes having a weak binding affinity with plasmonic nanostructures due to the short dwell time of the analyte on the surface. Here, we employed dynamic SERS, an acquisition method consisting of the rapid acquisition of a series of consecutive SERS spectra, to study the adsorption/desorption behavior of R6G on Ag surfaces. We demonstrated that the signal-noise ratio of SERS spectra of mobile molecules can be improved by dynamic SERS even when the acquisition time cannot catch up with the diffusion time of the molecule. More interestingly, we captured the neutral R6G0 state (spectroscopically different from the dominated positive R6G+ state) of R6G at the single-molecule level, which is a rare molecule event hardly detectable by traditional SERS. Dynamic SERS provides near real-time molecular vibrational information with an improved signal-noise ratio, which opens a new avenue to capture metastable or rare molecule events for the comprehensive understanding of interfacial processes related to catalysis and life science.

Mechanistic Investigation of a Self-Assembling Peptide against Escherichia coli.

Because of their distinctive mode of action in targeting bacterial cell membranes, antimicrobial peptides (AMPs) are increasingly regarded as a potential candidate for the development of novel antibiotics to combat the wide spread of bacterial resistance. To date, understanding of the exact molecular process by which AMPs act on the real bacterial envelope remains challenging. Simultaneously, the aggregated state of AMPs upon interaction with bacterial envelopes is still elusive. Previously, we have demonstrated that the potent antibacterial activity of a designed surfactant-like peptide Ac-A9K-NH2 benefited greatly from its high self-assembling ability and appropriate self-assembled morphologies and sizes. By using high-resolution atomic force microscopy, we here not only follow the variations of the Escherichia coli cell envelope in the presence of Ac-A9K-NH2 but also characterize the peptide aggregates on the bacterial surface as well as on the substrate surface. The results, together with those from fluorescence, zeta potential, circular dichroism, and scanning electron microscopy measurements, indicate that both the positively charged peptide monomers and self-assembled nanostructures can directly act on the negatively charged bacterial surface, followed by their insertion into the bacterial membrane, the formation of surface nanopores, and membrane lysis. The mechanism of Ac-A9K-NH2 against E. coli is thus consistent with the detergent-like mode of action. This work enhances our mechanistic understanding of the antibacterial behaviors of self-assembling peptides that will be valuable in exploring their biomedical applications.

Surface-Enhanced Raman Spectroscopy for Bioanalysis: Reliability and Challenges.

Surface-enhanced Raman spectroscopy (SERS) inherits the rich chemical fingerprint information on Raman spectroscopy and gains sensitivity by plasmon-enhanced excitation and scattering. In particular, most Raman peaks have a narrow width suitable for multiplex analysis, and the measurements can be conveniently made under ambient and aqueous conditions. These merits make SERS a very promising technique for studying complex biological systems, and SERS has attracted increasing interest in biorelated analysis. However, there are still great challenges that need to be addressed until it can be widely accepted by the biorelated communities, answer interesting biological questions, and solve fatal clinical problems. SERS applications in bioanalysis involve the complex interactions of plasmonic nanomaterials with biological systems and their environments. The reliability becomes the key issue of bioanalytical SERS in order to extract meaningful information from SERS data. This review provides a comprehensive overview of bioanalytical SERS with the main focus on the reliability issue. We first introduce the mechanism of SERS to guide the design of reliable SERS experiments with high detection sensitivity. We then introduce the current understanding of the interaction of nanomaterials with biological systems, mainly living cells, to guide the design of functionalized SERS nanoparticles for target detection. We further introduce the current status of label-free (direct) and labeled (indirect) SERS detections, for systems from biomolecules, to pathogens, to living cells, and we discuss the potential interferences from experimental design, measurement conditions, and data analysis. In the end, we give an outlook of the key challenges in bioanalytical SERS, including reproducibility, sensitivity, and spatial and time resolution.

Chicken thalamic injury induced by copper (II) or / and arsenite exposure involves oxidative stress and inflammation-induced apoptosis.

Copper (Cu) is a toxic substance of heavy metals, and arsenic (As) is a toxic substance of metalloids. They all cause oxidative stress and have been widely studied in recent years. Studies have reported that Cu and As can cause inflammation in chicken brain tissue. To assess the toxicological effects of Cu and/or As chronic exposure on chicken thalamus, we used toxicologically relevant concentrations of Cu and As in the chicken diet for 12 weeks. By comparative analysis, we found that higher malondialdehyde (MDA), total antioxidant capacity (T-AOC), and proinflammatory mediator (NF-κB) were observed in the Cu and/or As co-exposed group, indicating that oxidation stress and inflammation are produced. In addition, we also observed mitochondrial kinetics and the generation of apoptosis. These include the gene and protein expression levels of Drp1, Opa1, Mfn1, Mfn2 and Bcl-2, Bax, p53. In conclusion, we believe that in the chronic poisoning of Cu and/or As, inflammation occurs in the chicken thalamus, causing oxidative stress and mitochondrial kinetics, which eventually leads to apoptosis.