An alternative method for inferring Pandy's test using cerebrospinal fluid total protein.

Background: Pandy's test is used to assess the globulin level in cerebrospinal fluid (CSF). As a semi-quantitative manual method, the practicality and clinical value of Pandy's test has been challenged. Objective: We tend to summarize the relationship between CSF total protein (CSF-TP) quantification and Pandy's results, providing a formula to estimate Pandy's results merely by CSF-TP value. Methods: This retrospective study involved 1090 cases hospitalized in Huashan Hospital during 1/1/2023 to 20/4/2023. All samples were divided into six group based on their Pandy's results. Their corresponding CSF-TP quantitative results were subsequently analyzed and summarized. Another 364 patients were also gathered for verification. Results: The turbidity of samples won't affect examiners'ocular inspection and interpretation of Pandy's tests in positive groups. The results of Pandy's tests can be deduced based on CSF-TP quantitative results according to following rules: CSF-TP quantitative results 0-614 mg/L for Pandy negative (-), 615-1322 mg/L for extremely weak positive (±), 1323-2953 mg/L for weak positive (1+), 2954-6561 mg/L for medium positive results (2+), 6562-13007 mg/L for strong positive results (3+) and CSF-TP results >13007 for strongest positive (4+). The quantitative range above was experimentally verified as effective and correct by calculating the agreement rate through another 364 samples and the R ratio of each Pandy group was greater than 90 %. Conclusion: There is an excellent correlation between CSF-TP and Pandy's test. Therefore, CSF-TP quantification test through PROT Slides can be used to infer the results of Pandy's test to accelerate the abolish of this traditional manual test.

EasyNAT Malaria: a simple, rapid method to detect Plasmodium species using cross-priming amplification technology.

Malaria infection remains a serious threat to human health worldwide. Rapid and accurate detection technology is crucial for preventing malaria transmission and minimizing damage. We aimed to establish and validate a new rapid molecular detection method for malaria, called EasyNAT Malaria Assay, targeting Plasmodium vivax, Plasmodium falciparum, Plasmodium ovale, and Plasmodium malariae. The analytical performance of EasyNAT Malaria Assay was determined using positive materials. We identified 42 clinical samples as malaria positive and 95 negative samples. Each sample was examined by four methods: light microscopy, rapid diagnostic test, EasyNAT Malaria Assay, and digital PCR. Diagnostic accuracy and clinical performance were evaluated. The limit of detection (LOD)95% of EasyNAT Malaria was consistently 40 parasites/mL. It specifically amplified Plasmodium and performed with reliable repeatability and reproducibility. In 137 clinical samples, EasyNAT Malaria detected four more positive samples than microscopic examination and two more positive samples than rapid diagnostic test (RDT). One clinical sample was positive only under digital PCR. However, no significant differences statistically in sensitivity or specificity were observed. Compared with microscopy, the total, positive, and negative concordance rates of EasyNAT were 97.08%, 100%, and 95.79%, respectively. Enhanced diagnostic accuracy of EasyNAT Malaria in patients who had taken anti-malarial medication before their clinical appointment was observed. The EasyNAT Malaria Assay has good detection efficiency for clinical samples, presents a promising molecular detection tool in clinical practice, and is particularly suitable for rapid screening of high-risk populations in the emergency room. IMPORTANCE: This study established and validated EasyNAT Malaria Assay as a promising molecular detection tool for malaria screening of high-risk populations in clinical practice. This novel isothermal amplification method may effectively facilitate the rapid diagnosis of malaria and prevent its transmission.

Identification of the CD8+ T-cell Related Signature for Predicting the Prognosis of Gastric Cancer Based on Integrated Analysis of Bulk and Single-cell RNA Sequencing Data.

The infiltration of CD8+ T cells in the tumor microenvironment is associated with better survival and immunotherapy response. However, their roles in gastric cancer have not been explored so far. In here, the profiles of GC gene expression were collected from The Cancer Genome Atlas database. Single-cell transcriptomic data originated from GSE134520. Cell clustering, annotation, and CD8+ T-cell differential genes were from the TISCH database. We determined 896 CD8+ T-cell differential genes by scRNA-seq analysis. After integrating immune-related genes, 174 overlapping genes were obtained and a novel risk model was subsequently built. The performance of CD8+ T-cell-associated gene signature was assessed in the training and external validation sets. The gene signature showed independent risk factors of overall survival for GC. A quantitative nomogram was built to enhance the clinical efficacy of this signature. Furthermore, low-risk individuals showed higher mutation status, higher immune checkpoint expression, low Tumour Immune Dysfunction and Exclusion (TIDE) scores, and higher IPS-PD-1 combined IPS-CTLA4 scores, indicating a greater response to immunotherapy. In addition, analysis of IMvigor210 immunotherapy cohort demonstrated that low-risk individuals had a favorable response to prognosis and immunotherapy. In conclusion, we generated a CD8+ T-cell-related signature that can serve as a promising tool for personalized prognosis prediction and guiding decisions regarding immunotherapy in GC patients.

Globular adiponectin induces esophageal adenocarcinoma cell pyroptosis via the miR-378a-3p/UHRF1 axis.

BACKGROUND: Antiapoptosis is a major factor in the resistance of tumor cells to chemotherapy and radiotherapy. Thus, activation of cell pyroptosis may be an effective option to deal with antiapoptotic cancers such as esophageal adenocarcinoma (EAC). METHODS: Differential expression of ubiquitin-like versus PHD and ring finger structural domain 1 (UHRF1) in EAC and near normal tissues was analyzed, as well as the prognostic impact on survival in EAC. Also, the same study was done for globular adiponectin (gAD). Simultaneously, the mRNA expression of UHRF1 was observed in different EAC cell lines. Real time cellular analysis (RTCA) was used to detect cell proliferation, and flow cytometry and inverted fluorescence microscopy were used to detect pyroptosis. Biocredit analysis was conducted to observe the correlation between UHRF1 and key pyroptosis proteins. OD values and CCK8 assay were used to determine the effect of miR-378a-3p on EAC cells. Quantitative real-time polymerase chain reaction and Western blot were used to detect the correlation between UHRF1, gAD, and miR-378a-3p in EAC cells. Moreover, in vivo and in vitro experiments were performed to detect the relevant effects on tumor migration and invasion after inhibiting UHRF1 expression. RESULTS: UHRF1 was negatively correlated with the survival of patients with EAC, while miR-378a-3p showed the opposite effect. Additionally, gAD promoted EAC cell pyroptosis, upregulated miR-378a-3p, and significantly inhibited the proliferation of EAC cells. gAD directly reduced UHRF1 expression in EAC cells by upregulating miR-378a-3p. In cell migration and invasion assays, inhibition of UHRF1 expression significantly suppressed EAC cell metastasis. In animal experiments, we again demonstrated that gAD induced pyroptosis in EAC cells by inhibiting the expression of UHRF1. CONCLUSION: gAD-induced upregulation of miR-378a-3p significantly inhibited the proliferation of EAC by targeting UHRF1. Therefore, gAD may serve as an alternative therapy for chemotherapy- and radiation-refractory EAC or other cancers with the same mechanism of pyroptosis action.

Coordination of pinna, petiole, and root anatomical traits in 24 tropical-subtropical fern species.

Ferns are primitive vascular plants with diverse morphologies and structures. Plant anatomical traits and their linkages can reflect adaptation to the environment; however, these remain are still poorly understood in ferns. The main objective of this study was to explore whether there was structural coordination among and within organs in fern species. We measured 16 hydraulically related anatomical traits of pinnae, petioles, and roots of 24 representative fern species from the tropical and subtropical forest understory and analyzed trait correlation networks. In addition, we examined phylogenetic signals for the anatomical traits and analyzed co-evolutionary relationships. These results indicated that stomatal density and all petiole anatomical traits exhibited significant phylogenetic signals. Evolutionary correlations were observed between the tracheid diameter and wall thickness of the petiole and between the water transport capacity of the petiole and stomatal density. Conversely, anatomical traits of roots (e.g., root diameter) showed no phylogenetic signals and were not significantly correlated with those of the pinnae and petioles, indicating a lack of structural coordination between the below- and above-ground organs. Unlike angiosperms, vein density is unrelated to stomatal density or pinna thickness in ferns. As root diameter decreased, the cortex-to-stele diameter ratio decreased significantly (enhanced water absorption) in angiosperms but remained unchanged in ferns. These differences lead to different responses of ferns to climate change and improve our knowledge of the water adaptation strategies of ferns.

Regulation of ovalbumin allergenicity and structure-activity relationship analysis based on pulsed electric field technology.

The study focused on the regulation of ovalbumin (OVA) allergenicity using pulsed electric field (PEF) technology and examined the structure-activity link. Following PEF treatment, the ability of OVA to bind to IgE and IgG1 at 6 kHz was inhibited by 30.41 %. According to the microstructure, PEF caused cracks on the OVA surface. Spectral analysis revealed a blue shift in the amide I band and a decrease in α-helix and ß-sheet content indicating that the structure of OVA was unfolded. The disulfide bond conformation was transformed and the structure tended to be disordered. The increased fluorescence intensity indicated that tryptophan and tyrosine were exposed which led an increase in hydrophobicity. In addition, the results of molecular dynamics (MD) simulations confirmed that the stability of OVA was reduced after PEF, which was related to the reduction of hydrogen bonding and the sharp fluctuation of aspartic acid. Therefore, PEF treatment induced the exposure of hydrophobic amino acids and the transformation of disulfide bond configuration which in turn masked or destroyed allergenic epitopes, and ultimately inhibited OVA allergenicity. This study provided insightful information for the production of hypoallergenic eggs and promoted the use of PEF techniques in the food field.

Identification of three lncRNA-related prognostic signatures in gastric cancer by integrated multi-omics analysis.

Aims: The systematic identification of molecular features correlated with the clinical status of gastric cancer (GC) in patients is significant, although such investigation remains insufficient. Methods: GC subtyping based on RNA sequencing, copy number variation and DNA methylation data were derived from The Cancer Genome Atlas program. Prognostics lncRNA biomarkers for GC were identified by univariate Cox, LASSO and SVM-RFE analysis. Results: Three molecular subtypes with significant survival discrepancies, and their specific DEmRNAs and DElncRNAs were identified. Three reliable prognostic-associated lncRNA, including LINC00670, LINC00452 and LINC00160, were selected for GC. Conclusion: Our findings expanded the understanding on the regulatory network of lncRNAs in GC, providing potential targets for prognosis and treatment of GC patients.

Enhancing gel behavior of yellow croaker surimi by fruit extracts: Physicochemical properties and molecular mechanism.

The aim of this study was to investigate the effects of grape seed extract (GSE), acerola cherry extract (ACE), and blueberry extract (BBE) on the physicochemical properties and structure of the yellow croaker surimi gel. In addition, molecular docking and molecular dynamics (MD) simulation were utilized to study the binding mechanism of yellow croaker's fibrillin and fruit extracts. Surimi gel with 1.5% GSE, ACE, and BBE had the highest water holding capacity, hardness, chewability, cohesion, breaking force, breaking distance, gel strength, and densest 3D network structure, according to the experiment's findings. Nevertheless, the cross-linking of proteins in surimi was blocked with the further increase of fruit extract (1.5%-2.0%), and the existing network of surimi was weakened or even destroyed. Three fruit extracts had little effect on the secondary structure of the surimi gel. Besides, hydrophobic and disulfide bonds are the main chemical bonds of croaker surimi. Molecular docking showed that B-type procyanidine (BP) interacted with ASN-183, SER-571, ASP-525, ARG-350, LYS-188, GLU-349, CYS-353, and other active amino acids in croaker protein. Moreover, it can form strong hydrogen bond interaction with ASN-183, SER-571, ASP-525, and ARG-350 at the active sites of protein. The BP-Larimichthys crocea protein system's MD simulation was carried out, and calculations for the simulation's root mean square deviation, root mean square fluctuation, radius of gyration, solvent accessible surface area, and hydrogen bonds were made. It was found that these indices can demonstrate that the BP binding contributes to the stability of the yellow croaker structure.

YKL-40 promotes chemokine expression following drug-induced liver injury via TF-PAR1 pathway in mice.

Background: The inflammatory factor YKL-40 is associated with various inflammatory diseases and is key to remodeling inflammatory cells and tissues. YKL-40 (Chi3l1) promotes the activation of tissue factor (TF), leading to intrahepatic vascular coagulation (IAOC) and liver injury. TF is a key promoter of the exogenous coagulation cascade and is also involved in several signaling involving cell proliferation, apoptosis, charring, migration and inflammatory diseases pathways. However, the effect of YKL-40-induced TF-PAR1 pathway on the expression of downstream chemokines remains unknown. Methods: We established a liver injury model using Concanavalin A (ConA) in C57 BL/6 mice. By adopting various experimental techniques, the effect of YKL-40 induced TF-PAR1 pathway on the expression of downstream chemokine ligand 2 (CCL2) and IP-10 was verified. Results: We found that overexpression of YKL-40 increased the expression of TF, protease-activated receptor 1 (PAR1), CCL2 and IP-10 in mice and exacerbated the severity of liver injury. However, blocking the expression of TF significantly reversed the extent of liver injury. Conclusion: We found that YKL-40 promotes the expression of downstream chemokines ligand 2 (CCL2) and IP-10 by activating the TF-PAR1 pathway, leading to increased recruitment of inflammatory cells and exacerbating the progression of liver injury. This provides a new approach for the clinical treatment of drug-induced liver injury.

Mechanism of Targeted Regulation of Ovalbumin Epitopes by Pulsed Electric Field-Assisted Alcalase Treatment.

Egg is one of the eight major food allergens, and ovalbumin (OVA) is the most abundant allergenic protein in eggs. In this study, the effects of pulsed electric field (PEF)-assisted Alcalase hydrolysis on the spatial conformation and potential allergenicity of OVA were studied, and the mechanism of its inhibiting allergic reactions effect was revealed. PEF-assisted Alcalase hydrolysis increased the degree of hydrolysis, surface hydrophobicity, and free sulfhydryl group content. Moreover, the reduction in the α-helix content, fluorescence intensity, and disulfide bond content suggested that PEF promoted the OVA hydrolysis by Alcalase. Additionally, enzyme-linked immunosorbent assay data indicated that PEF-assisted Alcalase hydrolysis hindered OVA binding to immunoglobulins E and G1. Finally, based on bioinformatics combined with mass spectrometry, PEF-assisted Alcalase reduced OVA-induced allergic reactions by destroying epitopes in OVA. Overall, PEF technology further destroyed the epitopes of allergens by targeting the binding sites of substrates and enzymes to improve the affinity of enzymes and substrates, reducing allergic reactions.

Corn Silk Flavonoids Ameliorate Hyperuricemia via PI3K/AKT/NF-κB Pathway.

Hyperuricemia (HUA) is a widespread metabolic disease marked by an elevated level of uric acid, and is a risk factor for premature death. The protective effect of corn silk flavonoids (CSF) against HUA and its potential mechanisms were explored. Five important apoptosis and inflammation-related signaling pathways were identified by network pharmacological analysis. The CSF exhibited significant uric acid (UA)-lowering activity in vitro by decreasing xanthine oxidase (XOD) and increasing hypoxanthine-guanine phosphoribosyl transferase levels. In a potassium oxonate-induced HUA in vivo, CSF treatment effectively inhibited XOD activity and promoted UA excretion. Furthermore, it decreased the levels of TNF-α and IL-6 and restored pathological damage. In summary, CSF is a functional food component to improve HUA by reducing inflammation and apoptosis through the down-regulating PI3K/AKT/NF-κB pathway.

Identification of key immune genes of osteoporosis based on bioinformatics and machine learning.

Introduction: Immunity is involved in a variety of bone metabolic processes, especially osteoporosis. The aim of this study is to explore new bone immune-related markers by bioinformatics method and evaluate their ability to predict osteoporosis. Methods: The mRNA expression profiles were obtained from GSE7158 in Gene expression Omnibus (GEO), and immune-related genes were obtained from ImmPort database (https://www.immport.org/shared/). immune genes related to bone mineral density(BMD) were screened out for differential analysis. protein-protein interaction (PPIs) networks were used to analyze the interrelationships between different immune-related genes (DIRGs). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of DIRGs function were performed. A least absolute shrinkage and selection operation (LASSO) regression model and multiple Support Vector Machine-Recursive Feature Elimination (mSVM-RFE) model were constructed to identify the candidate genes for osteoporosis prediction The receiver operator characteristic (ROC) curves were used to validate the performances of predictive models and candidate genes in GEO database (GSE7158,GSE13850).Through the RT - qPCR verify the key genes differentially expressed in peripheral blood mononuclear cells Finally, we constructed a nomogram model for predicting osteoporosis based on five immune-related genes. CIBERSORT algorithm was used to calculate the relative proportion of 22 immune cells. Results: A total of 1158 DEGs and 66 DIRGs were identified between high-BMD and low-BMD women. These DIRGs were mainly enriched in cytokine-mediated signaling pathway, positive regulation of response to external stimulus and the cellular components of genes are mostly localized to external side of plasma membrane. And the KEGG enrichment analysis were mainly involved in Cytokine-cytokine receptor interaction, PI3K-Akt signaling pathway, Neuroactive ligand-receptor interaction,Natural killer cell mediated cytotoxicity. Then five key genes (CCR5, IAPP, IFNA4, IGHV3-73 and PTGER1) were identified and used as features to construct a predictive prognostic model for osteoporosis using the GSE7158 dataset. Conclusion: Immunity plays an important role in the development of osteoporosis.CCR5, IAPP, IFNA4, IGHV3-73 and PTGER1were play an important role in the occurrences and diagnosis of OP.

Enhanced effect and mechanism of nano Fe-Ca bimetallic oxide modified substrate on Cu(II) and Ni(II) removal in constructed wetland.

In this study, Fe2O3 nanoparticles (Fe2O3 NPs) and CaO NPs were loaded on the zeolite sphere carrier to create nano Fe-Ca bimetallic oxide (Fe-Ca-NBMO) modified substrate, which was introduced into constructed wetland (CW) to remove Cu(II) and Ni(II) via constructing "substrate-microorganism" system. Adsorption experiments showed that the equilibrium adsorption capacities of Fe-Ca-NBMO modified substrate for Cu(II) and Ni(II) were respectively 706.48 and 410.59 mg/kg at an initial concentration of 20 mg/L, 2.45 and 2.39 times of gravel. The Cu(II) and Ni(II) removal efficiencies in CW with Fe-Ca-NBMO modified substrate respectively reached 99.7% and 99.9% at an influent concentration of 100 mg/L, significantly higher than those in gravel-based CW (47.0% and 34.3%). Fe-Ca-NBMO modified substrate could promote Cu(II) and Ni(II) removal by increasing electrostatic adsorption, chemical precipitation, as well as the abundances of resistant microorganisms (Geobacter, Desulfuromonas, Zoogloea, Dechloromonas, and Desulfobacter) and functional genes (copA, cusABC, ABC.CD.P, gshB, and exbB). This study provided an effective method to enhance Cu(II) and Ni(II) removal of electroplating wastewater by CW with Fe-Ca-NBMO modified substrate.

Biomarkers for chemotherapy and drug resistance in the mismatch repair pathway.

Drugs targeting DNA repair have developed rapidly in cancer therapy, and numerous inhibitors have already been utilized in preclinical and clinical stages. To optimize the selection of patients for treatment, it is essential to discover biomarkers to anticipate chemotherapy response. The DNA mismatch repair (MMR) pathway is closely correlated with cancer susceptibility and plays an important role in the occurrence and development of cancers. Here, we give a concise introduction of the MMR genes and focus on the potential biomarkers of chemotherapeutic response and resistance. It has been clarified that the status of MMR may affect the outcome of chemotherapy. However, the specific underlying mechanisms as well as contradictory results continue to raise considerable controversy and concern. In this review, we summarize the current literature to provide a general overview.

Bio-clogging mitigation in constructed wetland using microbial fuel cells with novel hybrid air-photocathode.

Excessive accumulation of extracellular polymeric substances (EPS) in constructed wetland (CW) substrate can lead to bio-clogging and affect the long-term stable operation of CW. In this study, a microbial fuel cell (MFC) was coupled with air-photocathode to mitigate CW bio-clogging by enhancing the micro-electric field environment. Because TiO2/biochar could catalyze and accelerate oxygen reduction reaction, further promoting the gain of electric energy, the electricity generation of the tandem CW-photocatalytic fuel cell (CW-PFC) reached 90.78 mW m-3. After bio-clogging was mitigated in situ in tandem CW-PFC, the porosity of CW could be restored to about 62.5 % of the initial porosity, and the zeta potential of EPS showed an obvious increase (-14.98 mV). The removal efficiencies of NH4+-N and chemical oxygen demand (COD) in tandem CW-PFC were respectively 31.8 ± 7.2 % and 86.1 ± 6.8 %, higher than those in control system (21.1 ± 11.0 % and 73.3 ± 5.6 %). Tandem CW-PFC could accelerate the degradation of EPS into small molecules (such as aromatic protein) by enhancing the electron transfer. Furthermore, microbiome structure analysis indicated that the enrichment of characteristic microorganisms (Anaerovorax) for degradation of protein-related pollutants, and electroactive bacteria (Geobacter and Trichococcus) promoted EPS degradation and electron transfer. The degradation of EPS might be attributed to the up-regulation of the abundances of carbohydrate and amino acid metabolism. This study provided a promising new strategy for synergic mitigation and prevention of bio-clogging in CW by coupling with MFC and photocatalysis.

Efficacy of Baishao Luoshi decoction on synaptic plasticity in rats with post stroke spasticity.

OBJECTIVE: To evaluate the efficacy of Baishao Luoshi decoction (, BD) on synaptic plasticity in rats with post stroke spasticity (PSS), and to study the mechanism behind the action. METHODS: The PSS model of rat was established by middle cerebral artery occlusion (MCAO). The neurological deficit symptoms were evaluated by modified neurological deficit score (mNSS). Muscle tension were evaluated by Modified Ashworth score (MAS). Transmission electron microscopy (TEM) was used to observe the synaptic ultrastructure. The expression of synaptic plasticity-related protein brain derived neurotrophic factor (BDNF), growth associated protein-43 (GAP43), synaptophysin (p38) and microtubule-associated protein 2 (MAP2) in the brain tissue around the infarct were detected by Western blotting. RESULTS: We found that mNSS were significantly improved and limb spasticity was ameliorated treated by BD. The thickness of postsynaptic density and the synaptic curvature increased significantly. The expression of synaptic plasticity-related protein BDNF, GAP43, p38, MAP2 in the brain tissue around the infarct were raised remarkably after treated by BD. CONCLUSIONS: Alleviating PSS by BD may be related to rescuing the synaptic plasticity, which provides a probable new therapeutic method for PSS.

Pulsed Electric Field-Assisted Alcalase Treatment Reduces the Allergenicity and Eliminates the Antigenic Epitopes of Ovomucoid.

Physically assisted chemical modifications can effectively reduce the allergenicity of ovomucoid (OVM). However, only a few studies have used pulsed electric field (PEF)-assisted alcalase hydrolysis to reduce the allergenicity of OVM. Herein, we investigated the effect of PEF-assisted alcalase treatment on the spatial conformation, allergenicity, and antigenic epitopes of OVM based on multispectroscopic analyses, bioinformatics, and mass spectrometry. The results showed that PEF-assisted alcalase treatment promoted the hydrolysis of OVM; moreover, the α-helix content and surface hydrophobicity of OVM significantly decreased, which disordered its spatial conformation and weakened its intermolecular interactions. Additionally, enzyme-linked immunosorbent assay (ELISA) results showed that the PEF-assisted alcalase treatment significantly reduced the binding levels of IgE and IgG1, which were 47.66 and 36.41%, respectively. Finally, eight epitopes of OVM were obtained by immunoinformatic tools. Nano-high performance liquid chromatography coupled to tandem mass spectrometry (nano-HPLC MS/MS) results showed that the hydrolysate of OVM and alcalase (HOVM) had nine more peptide-containing epitopes than the hydrolysate of PEF-treated OVM and PEF-treated alcalase (HOVM-PP'), indicating that PEF could promote the elimination of linear epitopes in OVM, thereby reducing OVM allergenicity.

TDDFT study on the simultaneous sensing mechanism for peroxynitrite and glutathione by a bifunctional fluorescent probe.

Using time-dependent density functional theory (TDDFT) method, the response mechanism of a reported bifunctional fluorescent probe for simultaneous recognition of peroxynitrite and glutathione (Chem. Commun. 2018, 54, 11336) was theoretically studied. Calculated vertical excitation energies based on the ground-state and excited-state geometries were consistent with the corresponding experimental ultraviolet-visible and fluorescence spectra. In the ground state, electron delocalization in the probe was limited because its geometry was restrained by steric hindrance. Frontier molecular orbital analysis has shown that the probe should undergo photoinduced electron transfer (PET) from the benzothiazole moiety to the maleimide moiety after excitation. The nonplanar structure together with PET led to fluorescence quenching of the probe. The probe could be dealkylated by peroxynitrite anion. The resulting intramolecular hydrogen bond increasesd the planarity of the molecule, while also gave rise to an excited-state proton-transfer process. Moreover, the addition reaction between the probe and glutathione inhibited the PET process. These two analytes together contributed to the fluorescence enhancement of the final product. This theoretical sensing mechanism for peroxynitrite and glutathione may potentially be important for the design and enhancement of novel probes.

Evaluation of Fourier transform infrared (FTIR) spectroscopy with multivariate analysis as a novel diagnostic tool for lymph node metastasis in gastric cancer.

Fourier transform infrared (FTIR) spectroscopy is a vibration spectroscopy that uses infrared radiation to vibrate to absorb the molecular bonds in its absorbed sample. The main purpose of this study was to evaluate FTIR spectroscopy as a novel diagnostic tool for lymph node metastasis (LNM) of gastric cancer. We collected 160 fresh non-metastatic and metastatic lymph nodes (80 each) from 60 patients with gastric cancer for spectral analysis. FTIR spectra of lymph node (LN) samples were obtained in the wavenumber range of 4000 cm-1 to 900 cm-1. We calculated the changes in the ratio of spectral intensity (/ I1460). Principal component analysis (PCA) and Fisher's discriminant analysis (FDA) were used to distinguish malignant from normal LN. Four significant bands at 1080 cm-1, 1640 cm-1, 1740 cm-1 and 3260 cm-1 separated metastatic and non-metastatic LN spectra into two distinct groups by PCA.T-tests showed that, along with the relative intensity ratios (I1080/I1460, I1640/I1460, I3260/I1460, I1740/I1460), these band ratios were also able to differentiate between malignant and benign LN spectra. Six parameters (P1080 cm-1, P1300 cm-1, I1080/I1460, I1640/I1460, I3260/I1460, I1740/I1460) were selected as independent factors to set up discriminant functions. The sensitivity of FTIR spectroscopy in diagnosing LNM was 95 % by discriminant analysis. Our study suggested that FTIR spectroscopy can be a useful tool to examine LNM with high sensitivity and specificity for LNM diagnosis. Therefore it can be used in clinical practice as a non-invasive method.

Synthesis of Tetrahydro-5H-indolo[2,3-b]quinolines through Copper-Catalyzed Cascade Reactions of Aza-o-quinone Methides with Indoles.

A variety of tetrahydro-5H-indolo[2,3-b]quinolines were prepared in 40-97% yields through a copper(II)-catalyzed cascade reaction of aza-o-quinone methides generated in situ from 2-(chloromethyl)anilines and indoles. Experimental results showed that the reaction underwent double 1,4-additions and sequential intramolecular cyclization. The present method features broad substrate scope, good functional group tolerance, and easy gram scalable preparation of indolo[2,3-b]quinolines.