In vitro inhibition of α-Synuclein aggregation and disaggregation of preformed fibers by polyphenol hybrids with 2-conjugated benzothiazole.

The misfolding and aggregation of α-Syn play a pivotal role in connecting diverse pathological pathways in Parkinson's disease (PD). Preserving α-Syn proteostasis and functionality by inhibiting its aggregation or disaggregating existing aggregates using suitable inhibitors represents a promising strategy for PD prevention and treatment. In this study, a series of benzothiazole-polyphenol hybrids was designed and synthesized. Three identified compounds exhibited notable inhibitory activities against α-Syn aggregation in vitro, with IC50 values in the low micromolar range. These inhibitors demonstrated sustained inhibitory effects throughout the entire aggregation process, stabilizing α-Syn proteostasis conformation. Moreover, the compounds effectively disintegrated preformed α-Syn oligomers and fibers, potentially by binding to specific domains within the fibers, inducing fibril instability, collapse, and ultimately resulting in smaller-sized aggregates and monomers. These findings offer valuable insights into the therapeutic potential of polyphenol hybrids with 2-conjugated benzothiazole targeting α-Syn aggregation in the treatment of PD.

Synthesis of N-(2-Hydroxyaryl)benzotriazoles via Metal-Free O-Arylation and N-O Bond Cleavage.

A metal-free method for synthesis of N-(2-hydroxyaryl)benzotriazoles via O-arylation of N-hydroxybenzotriazoles with readily available diaryliodonium salts and sequential N-O bond cleavage under mild conditions has been developed. The [3,3]-rearrangement of N-O bond cleavage could take place on the N instead of C atom. The reaction was compatible with diverse functional groups and a new type of P,N-ligand was synthesized in three steps.

Tandem C-O and C-N Bonds Formation Through O-Arylation and [3,3]-Rearrangement by Diaryliodonium Salts: Synthesis of N-Aryl Benzo[1,2,3]triazin-4(1H)-one Derivatives.

Metal-free O-arylation and [3, 3]-rearrangement have been shown as an efficient strategy to construct new C-O and C-N bonds in one-pot reactions. The method was used to prepare N-aryl benzo[1,2,3]triazin-4(1H)-one derivatives in good yields from N-hydroxy benzo[1,2,3]triazin-4(3H)-one and diaryliodonium salts. The reaction was tolerated a variety of sensitive functional groups such as iodine, nitro, ester, and aldehyde groups. A rational mechanism was proposed based on the experimental results, and the reaction was easily up to gram scale.

Synthesis of α,ß-Unsaturated N-Aryl Ketonitrones from Oximes and Diaryliodonium Salts: Observation of a Metal-Free N-Arylation Process.

An efficient transition-metal-free method for the preparation of α,ß-unsaturated N-aryl ketonitrones under mild conditions has been developed. This reaction shows good functional group tolerance for both electron-rich and electron-deficient substituents on both oximes and diaryliodonium salts. Two examples of gram-scale preparations have been realized in good yields. Further transformations of these nitrones to different N-heterocycles have been demonstrated. DFT calculations suggest that N-arylation products are formed by [1,3]-phenyl migration of an O-coordinated oximate complex via a four-centered transition state, while the O-arylation products are formed by [1,3]-phenyl migration of a N-coordinated oximate complex.

Associations between aberrant DNA methylation and transcript levels of DNMT1 and MBD2 in CD4+T cells from patients with systemic lupus erythematosus.

BACKGROUND/OBJECTIVES: It seems that global DNA hypomethylation in CD4+T cells is linked to the pathogenesis of systemic lupus erythematosus (SLE). However, the underlying mechanism by which SLE patients show hypomethylated DNA remains unclear. This study explored the relationship between DNA methylation patterns and expression levels of DNA methyltransferases (DNMT1) and MBD2 in CD4+T cells of SLE patients. METHODS: CD4+T cells were obtained from 30 patients with SLE and 18 normal controls. The global DNA methylation levels in CD4+T cells were evaluated by the Methyflash DNA methylation quantification kit. The mRNA levels of DNMT1 and MBD2 were quantified by quantitative real-time polymerase chain reaction. RESULTS: SLE patients had significantly lower global DNA methylation levels than controls, and the global DNA methylation was inversely correlated with the SLE disease activity index (SLEDAI). The mRNA levels of DNMT1 in SLE patients were significantly lower than that of controls and there was no correlation between DNMT1 mRNA levels and SLEDAI but there was a positive correlation between DNMT1 mRNA levels and global DNA methylation. The mRNA levels of MBD2 in SLE patients were significantly higher than in controls, and there was positive correlation between MBD2 mRNA levels and SLEDAI and an inverse correlation between MBD2 mRNA levels and global DNA methylation. CONCLUSIONS: Global DNA hypomethylation may play a pivotal role in the pathogenesis of SLE. Abnormal expression levels of DNMT1 and MBD2 mRNA may be important causes of the global hypomethylation observed in CD4+T cells in SLE.

Synthesis of 1,2,4-Oxadiazolines through Deoxygenative Cyclization of N-Vinyl-α,ß-Unsaturated Nitrones with in Situ Generated Nitrile Oxides from Hydroxamoyl Chlorides.

A variety of 1,2,4-oxadiazoline derivatives were synthesized in moderate to good yields through a deoxygenative cyclization cascade reaction of N-vinyl-α,ß-unsaturated nitrones and hydroxamoyl chlorides. Mechanistic studies revealed that the reaction underwent double additions of nitrile oxides to N-vinyl-α,ß-unsaturated nitrones, sequential elimination, and intramolecular cyclization to afford 1,2,4-oxadiazolines. Alternatively, 1,2,5-oxadiazolines were also obtained as major products in i-PrOH solvent through [3 + 3] cycloaddition and selective [3,3]-rearrangement. Moreover, the prepared 1,2,4-oxadiazolines were easily converted to polysubstituted pyrroles under thermal conditions.

Nickel(II)-Catalyzed [3 + 2] Cycloaddition of Nitrones and Allenoates to Access N-Vinylindoles and N-Vinylpyrroles.

A variety of N-vinylindoles and N-vinylpyrroles were prepared in moderate to good yields through the nickel(II)-catalyzed [3 + 2] cycloaddition of α,ß-unsaturated nitrones with allenoates under mild reaction conditions. A rational mechanism for the formation of N-vinylindoles was proposed based on the 18O-labeled experiments and key intermediates detected by high-resolution mass spectrometry trace experiments. The present method highlights a nickel(II)-controlled cyclization, atom-economical reaction, broad substrate scope, good functional group tolerance, and high Z-stereoselectivity for the enamine bond.

New gene selection method for multiclass tumor classification by class centroid.

In the analysis of gene expression profiles, the selection of genetic markers and precise diagnosis of cancer type are crucial for successful treatment. The selection of discriminatory genes is critical to improve the accuracy and decrease computational complexity and cost in microarray analysis. In this paper, we developed a new statistical parameter, the suitability score to filter genes which only utilize sample distances from the class centroid. The filtered genes are employed in the nearest centroid classification to classify cancer. To evaluate the performance of the new statistical parameter, the proposed approach is applied to three publicly available microarray datasets. In this paper we demonstrate that the proposed gene selection method is steady in handling classification tasks and is a useful tool for gene selection and mining high dimension data.

Hybrid particle swarm optimization and tabu search approach for selecting genes for tumor classification using gene expression data.

Gene expression data are characterized by thousands even tens of thousands of measured genes on only a few tissue samples. This can lead either to possible overfitting and dimensional curse or even to a complete failure in analysis of microarray data. Gene selection is an important component for gene expression-based tumor classification systems. In this paper, we develop a hybrid particle swarm optimization (PSO) and tabu search (HPSOTS) approach for gene selection for tumor classification. The incorporation of tabu search (TS) as a local improvement procedure enables the algorithm HPSOTS to overleap local optima and show satisfactory performance. The proposed approach is applied to three different microarray data sets. Moreover, we compare the performance of HPSOTS on these datasets to that of stepwise selection, the pure TS and PSO algorithm. It has been demonstrated that the HPSOTS is a useful tool for gene selection and mining high dimension data.

QSAR analysis of tyrosine kinase inhibitor using modified ant colony optimization and multiple linear regression.

Quantitative structure-activity relationship (QSAR) models of inhibiting action of some analogues of 4-(3-bromoanilino)-6,7-dimethoxyquinazoline on epidermal growth factor receptor tyrosine kinase were constructed using modified ant colony optimization (ACO) method. As a comparison to this method, the evolutionary algorithm (EA) was also tested. It has been demonstrated that the modified ACO is a useful tool for variable selection comparable to EA. In the selected descriptors, electronic descriptor sigma(Y)(-) is the most important descriptor in predicting EGFR inhibitory activity. Electron-donating groups such as Y-substituents enhance the activity as evident by negative sigma(Y)(-). In addition, for quinazoline substituents, nitro group has a large deactivating effect.

Analysis of genital Candida albicans infection by rapid microsatellite markers genotyping.

BACKGROUND: Candida albicans (C. albicans) infection, often occurring in genital candidiasis, has increased dramatically recently. Developing an efficient C. albicans typing method may contribute to understanding its epidemiological characteristics and guiding efficient treatment. We used rapid microsatellite genotyping assay for interstrain differentiation of C. albicans isolates and explored some characteristics of its spread. METHODS: DNA was extracted from C. albicans isolates from gentalia, recta and mouths of 39 female cases and 27 male cases of genital candidiasis. Three fluorescent primers for the microsatellite markers in conserved genes (CDC3, EF3 and HIS3) of C. albicans were used to amplify the isolates DNA by PCR. Fluorescent signals were read with an automatic sequencer and analyzed with GeneScan software. RESULTS: Analysis of the three microsatellites markers showed 18 gene allelic associations in genital C. albicans infected patients: 10 allelic associations in female and 11 allelic associations in male, of which 3 allelic associations shared by both genders covered 71% of infections. The most dominant allele association of pathogenic strains for both genders was 116:124, 122:131, 160:200 that covered about 50% of infection. Gentalia and recta shared the same strains in 80% of female patients, but in only 3.8% of male patients. There were 2.7% female patients, but no males, with same strain in both gentalia and mouths. Five of seven genital C. albicans infected couples had the same allelic associations of which 4 were the dominant pathogenic C. albicans susceptible for both genders. CONCLUSIONS: The predominant allelic association of the pathogenic strain in genital C. albicans infection is 116:124, 122:131, 160:200. Vaginal pathogenic strains are probably maintained from the rectal reservoir. Pathogenic strains of male patients are probably from frequent sexual intercourse. The aggressiveness of some strains varies with gender.

Particle swarm algorithm trained neural network for QSAR studies of inhibitors of platelet-derived growth factor receptor phosphorylation.

The multilayer feed-forward artificial neural network (ANN) has been widely used in QSAR studying. Back-propagation algorithm (BP) and the use of evolutionary search as an ANN training method has some limitations associated with overfitting, local optimum problems and slow convergence rate. In this paper, particle swarm optimization (PSO) as a relatively new optimization technique has been used in ANN training. Compared to ANN trained by BP algorithm and evolutionary search, ANN training by PSO algorithm (PSONN) show satisfactory performance, converges quickly towards the optimal position and can avoid overfitting in some extent. The PSONN has been testified by using in QSAR modeling for inhibitory activity of 4-[4-(N-substituted (thio) carbamoyl)-1-piperazinyl]-6,7-dimethoxyquinazoline derivatives.

Practical Quantum Private Database Queries Based on Passive Round-Robin Differential Phase-shift Quantum Key Distribution.

A novel quantum private database query protocol is proposed, based on passive round-robin differential phase-shift quantum key distribution. Compared with previous quantum private database query protocols, the present protocol has the following unique merits: (i) the user Alice can obtain one and only one key bit so that both the efficiency and security of the present protocol can be ensured, and (ii) it does not require to change the length difference of the two arms in a Mach-Zehnder interferometer and just chooses two pulses passively to interfere with so that it is much simpler and more practical. The present protocol is also proved to be secure in terms of the user security and database security.

Quantum Hash function and its application to privacy amplification in quantum key distribution, pseudo-random number generation and image encryption.

Quantum information and quantum computation have achieved a huge success during the last years. In this paper, we investigate the capability of quantum Hash function, which can be constructed by subtly modifying quantum walks, a famous quantum computation model. It is found that quantum Hash function can act as a hash function for the privacy amplification process of quantum key distribution systems with higher security. As a byproduct, quantum Hash function can also be used for pseudo-random number generation due to its inherent chaotic dynamics. Further we discuss the application of quantum Hash function to image encryption and propose a novel image encryption algorithm. Numerical simulations and performance comparisons show that quantum Hash function is eligible for privacy amplification in quantum key distribution, pseudo-random number generation and image encryption in terms of various hash tests and randomness tests. It extends the scope of application of quantum computation and quantum information.

Construction and expression of a Rev-dependent TNF-R1 expressing HIV-infected-cell injurious vectors.

BACKGROUND: Rev is necessary for exporting unspliced and incompletely spliced intron containing HIV mRNAs and for HIV replication. The aim of this study is to develop a kind of selective suicide construct that can specifically and directly induce HIV infected cells into apoptosis based on the high affinity of Rev and Rev response element (RRE). METHODS: Molecular-cloning technique was used to synthesis Rev dependent TNF-R1 expression construct pDM128-TNF-R1 (pT128) that contains RRE and TNFR1 gene. Restriction digestion, Polymerase Chain Reaction (PCR) and DNA sequencing were processed and the exactness and correctness of the inserted TNF-R1 gene in pT128 were confirmed repeatedly. The expression of pT128 co-transfected with different combination of other plasmids by calcium phosphate-DNA co-precipitation in Helas and by gene gun transfection in keratinocytes was further tested by flow-cytometry and cell counted under microscope. RESULTS: The new plasmid specifically expressed TNF-R1 in Helas when co-transfected with pRev but did not when without pRev. Indirect expression of TNF-R1 from pT128 was slower than the direct expression of that from Hu p60 TNFR1 in pDC302 (pT60), but all those pT60 or pT128 transfected cells showed apoptosis at last while TNF-R1 was sufficiently expressed. Other kinds of Rev expression construct such as pAD8 and a chimeric HIV vaccine also can switched on the selective expression of pT128. Not only Rev-dependent expression in Helas, pT128 also normally expressed its TNF-R1 in keratinocytes. Co-transfected with pRev or pAD8 that expressed Rev, pT128 expressed TNF-R1 and induced apoptosis of green fluorescent keratinocytes in skin explant. The number of green fluorescent keratinocytes co-transfected by pT128 plus pRev or pAD8 was gradually outnumbered by that co-transfected by pT128 only. The difference was more significant after culturing for 72 hours. CONCLUSIONS: Rev dependent pT128 is able to selectively induce apoptosis of HIV-infected or Rev-expressed target cells by expression of TNF-R1. The new strategy based on manipulation of the regulatory protein of HIV may be valuable in design of new HIV vaccine.

[The effect of specific virus delivering of Langerhans cell for the M-tropic HIV infection].

OBJECTIVE: To observe the cellular mechanism of via skin infection of Microphage tropic (M-tropic) HIV and further differentiate the infection of M-tropic and T-tropic HIV. METHODS: DNA clone of AD8 and NL43 was respectively transfected to skin by Gene Gun, The expression of virus in the epidermal cells was observed by flow-cytometry and fluoroscope. Emigrating cells were Mac-sorted into CD80+ and CD80-. The infection of CD4+ T lymphocytes by HIV from emigrating cells were further assessed by PCR and RT assay. RESULTS: Through direct transfection of skin by Gene Gun, emigrating cells from skin showed transfection of AD8 and NL43 and the gag gene can be amplified from the cells. Only AD8 transfected emigrating cells can further infect CD4+ T lymphocyte. Gag can be amplified and reverse transcriptase can be expressed from these CD4+ T cells; NL43 transfected emigrating cells can not infect CD4+ T lymphocyte. No gag can be amplified and no reverse transcriptase can be expressed. AD8 transfected and 1/2 log diluted CD80+ cells can infect CD4+ T lymphocyte. Even after 4 dilutions, there are still a lot of CD4+ T cells, gag can be amplified and a large amount of reverse transcriptase was expressed that is double or triple of controls. AD8 infected CD80-cells co-cultured with CD4+ T cells showed gag amplification only in first dilution and reverse transcriptase is also expressed. Gag can not be amplified by further dilution. NL43 infected CD80+ or CD80- emigrating cells co-cultured with CD4+ T cells did not show gag amplification and did not express reverse transcriptase. CONCLUSION: Direct AD8 transfected CD80+ emigrating epidermal cells can specifically infect CD4+ T lymphocyte. This specificity not only depends on affinitive combination of HIV receptor on cell surface, but also on the specific virus delivering of AD8 transfected CD80+ cells that infect the CD4+ T cells. That means even without the receptor, CD80+ cells only deliver transfected AD8 but not NL43. So, it can be said that the specificity of the virus receptor is not the only clue of HIV infection.

Radiosensitivity of hepatocarcinoma cell line BEL-7402.

OBJECTIVE: To assess the radiosensitivity of human hepatocarcinoma cell line BEL-7402. METHODS: Human hepatocarcinoma cell line BEL-7402 was cultured in vitro and then subjected to exposure to 6 MV X-ray at the doses ranging from 0 to 10 Gy. The survival rate of the cells following the exposure was assessed by determining the colony-forming units during further cell culture 12 to 14 d after the exposure, and the parameters for the radiosensitivity calculated. RESULTS and CONCLUSION: The parameters of BEL-7402 cells (D0=1.6, Dq=1.3, n=2, 4, SF2=0.63+/-0.05 Gy) demonstrates a high sensitivity of the cells to radiation.

[Nutrition support of severe illness patients of general surgery during peroperation period].

OBJECTIVE: To study the clinical effect of the nutrition support of severe illness patients of general surgery during peroperation period. METHODS: To analyse application of the nutrition support applied to 147 cases with severe illness of general surgery in peroperation period since 1995. In 147 cases, there were abdominal operations(n=138, 93.9%) and cervical operations(n=9, 6.1%) and emergency operations (n=63, 42.8%). Total parenteral nutrition (TPN) was used by venous canal ways including internal jugular vein (n=132, 89.8%), axillary vein (n=11, 7.5%), femoral vein (n=4, 2.7%), used unicameral catheter (n=127, 86.4%), double catheter (n=20, 13.6%), 41 cases were used enteral nutrition. Two different nutritional support treatments were employed, one was TPN-->parenteral nutrition(PN)+oral diet-->oral diet (n=106, 72.1%) and another was TPN-->PN+enteral nutrition(EN)-->EN-->EN+oral diet-->oral diet (n=41, 27.9%). RESULTS: There were not complications of catheterization and metabolism in the nutrition support, 142 cases (96.6%) had been cured and 5 cases (3.4%) died of primary diseases after operation. CONCLUSION: The nutrition support of patients with severe illness of general surgery in peroperation period is an important adjuvant treatment that can assure operative safety and promote recovery on postoperation.