Photocleavable DNA Nanotube-Based Dual-Amplified Resonance Rayleigh Scattering System for MicroRNA Detection Incorporating Molecular Computing-Cascaded Keypad Lock Functionality.

Cascade molecular events in complex systems are of vital importance for enhancing molecular diagnosis and information processing. However, the conversion of a cascaded biosensing system into a multilayer encrypted molecular keypad lock remains a significant challenge in the development of molecular logic devices. In this study, we present a photocleavable DNA nanotube-based dual-amplified resonance Rayleigh scattering (RRS) system for detecting microRNA-126 (miR-126).

Long noncoding RNA XLOC_006786 inhibits the proliferation, invasion and metastasis of osteosarcoma cells through NOTCH3 signaling pathway by targeting miR-491-5p.

Recent research has indicated that Long noncoding RNAs (LncRNAs) are crucial in many disorders, especially tumors. However, the exact role of LncRNA XLOC_006786 (LncRNA-SPIDR-2:1) in malignancies, especially in human osteosarcoma, is unclear. The results of RT‒qPCR, western blotting, CCK-8 assays, and Transwell assays showed that LncRNA XLOC_006786 inhibited osteosarcoma cell proliferation, invasion, and migration, indicating that it may be a tumor suppressor gene in osteosarcoma.

High-Efficiency CdSe Quantum Dots/FeO@MoS/SO Electrochemiluminescence System Based on a Microfluidic Analysis Platform for the Sensitive Detection of Neuron-Specific Enolase.

In this work, based on electrochemiluminescence (ECL) technology and self-assembled portable disease detection chips, a bioactivity-maintained sensing platform was developed for the quantitative detection of neuron-specific enolase. First, we prepared FeO@MoS nanocomposites as an efficient catalyst to accelerate the reduction of persulfate (SO). Specifically, abundant sulfate radicals (SO) were generated because of cyclic conversion between Fe and Fe.

Perceived Importance of Breast Cancer Risk Factors: A Survey on 386 Physicians in China.

There are varying definitions of women at high risk of breast cancer across different institutions, and there are reports suggesting that the breast cancer risk assessment tools have not been well integrated into clinical practice. In this study, we tried to investigate the perceived importance of different breast cancer risk factors by physicians in China. A cross-sectional survey involving 386 anonymous physicians was conducted using a 20-item, 5-point Likert scale questionnaire.

An Intron Variant of SLC2A9 Increases the Risk for Type 2 Diabetes Mellitus Complicated with Hyperuricemia in Chinese Male Population.

Background: The aim of this study was to explore the associations of haplotypes of the glucose transporter 9 (SLC2A9) genes with type 2 diabetes mellitus (T2DM) complicated with hyperuricemia (HUA).

Methods: Overall, 608 Chinese males, enrolled from the Affiliated Hospital of Medical College of Qingdao University in 2009-2012, were genotyped. The subjects included 167 withT2DM (average age of onset (58.

Hydroxyl regioisomerization of anthracycline catalyzed by a four-enzyme cascade.

Ranking among the most effective anticancer drugs, anthracyclines represent an important family of aromatic polyketides generated by type II polyketide synthases (PKSs). After formation of polyketide cores, the post-PKS tailoring modifications endow the scaffold with various structural diversities and biological activities. Here we demonstrate an unprecedented four-enzyme-participated hydroxyl regioisomerization process involved in the biosynthesis of kosinostatin.

Unconventional origin and hybrid system for construction of pyrrolopyrrole moiety in kosinostatin biosynthesis.

Kosinostatin (KST), an antitumor antibiotic, features a pyrrolopyrrole moiety spirally jointed to a five-membered ring of an anthraquinone framework glycosylated with a γ-branched octose. By a combination of in silico analysis, genetic characterization, biochemical assay, and precursor feeding experiments, a biosynthetic pathway for KST was proposed, which revealed (1) the pyrrolopyrrole moiety originates from nicotinic acid and ribose, (2) the bicyclic amidine is constructed by a process similar to the tryptophan biosynthetic pathway, and (3) a discrete adenylation enzyme and a peptidyl carrier protein (PCP) are responsible for producing a PCP-tethered building block parallel to type II polyketide synthase (PKS) rather than for the PKS priming step by providing the starter unit. These findings provide an opportunity to further explore the inexplicable enzymatic logic that governs the formation of pyrrolopyrrole moiety and the spirocyclic skeleton.

Efficient synthesis of a chiral precursor for angiotensin-converting enzyme (ACE) inhibitors in high space-time yield by a new reductase without external cofactors.

A new reductase, CgKR2, with the ability to reduce ethyl 2-oxo-4-phenylbutyrate (OPBE) to ethyl (R)-2-hydroxy-4-phenylbutyrate ((R)-HPBE), an important chiral precursor for angiotensin-converting enzyme (ACE) inhibitors, was discovered. For the first time, (R)-HPBE with >99% ee was produced via bioreduction of OPBE at 1 M without external addition of cofactors. The space-time yield (700 g·L(-1)·d(-1)) was 27 times higher than the highest record.

Biocatalytic properties of a recombinant aldo-keto reductase with broad substrate spectrum and excellent stereoselectivity.

In the screening of 11 E. coli strains overexpressing recombinant oxidoreductases from Bacillus sp. ECU0013, an NADPH-dependent aldo-keto reductase (YtbE) was identified with capability of producing chiral alcohols.

[Study on the aggregation behavior of cationic porphyrins and their interaction with ctDNA].

Interest in the interaction between cationic porphyrins, particularly derivatives of meso-tetra(N-methylpyridinium-4-yl) porphyrin(TMPyP), and DNA abounds because they are versatile DNA-binding agents that could find application in photodynamic therapy, cancer detection, artificial nucleases, virus inhibition and so on. The interaction of two water-soluble cationic porphyrins, meso-tetrakis(4-N, N, N-trimethylanilinium) porphyrin (TMAP) and 5-phenyl-10,15,20-tris[4-(N-methyl) pyridinium]porphyrin (TriMPyP), with calf thymus DNA (ctDNA) was studied by UV-Vis absorption spectroscopy, fluorescence spectroscopy and resonance light scattering technique. TriMPyP forms aggregate in water due to the molecular asymmetry while TMAP exists as monomers.

Spectroscopic studies on the interaction of a water-soluble cationic porphyrin with proteins.

The interaction of a water-soluble cationic porphyrin, meso-tetrakis (4-N,N,N-trimethylanilinium) porphyrin (TMAP), with two proteins, bovine serum albumin (BSA) and human serum albumin (HSA), was studied by UV-vis absorption spectroscopy, fluorescence spectroscopy, fluorescence anisotropy and synchronous fluorescence spectroscopy at neutral aqueous solutions. Free base TMAP bound to proteins as monomers and no aggregation was observed. The binding of TMAP quenched the fluorescence of the protein.

[Study on binding mechanism of meso-tetra-(3,5-dibromo-4-hydroxyphenyl) porphyrin with protein by fluorescence method].

Studies on the binding mechanism between protein and small molecules could give us lots of useful information. For example, a detailed characterization of drug-protein binding properties was essential for understanding the function of delivery, hence, interest in the mechanism of the interaction between them has attracted much research using different methods. In the present paper, the interaction mechanism between meso-tetra-(3,5-dibromo-4-hydroxyphenyl) porphyrin [T(DBHP)P] and bovine serum albumin (BSA) was investigated using fluorescence method.

[Study and application of determination of protein with meso-tetra-(3,5-dibromo-4-hydroxyphenyl) porphyrin fading spectrophotometry].

In the present paper, the binding characteristics and spectral behavior of interaction of meso-tetra-(3, 5-dibromo-4-hydroxyphenyl) porphyrin [T(DBHP)P] as a new-style probe with protein were studied by the techniques of spectrophotometry. The experiment showed that Tween-80 microemulsion was efficiently used to enhance the sensibility and stability of the system at pH 4. 17(Britton-Robinson buffer solution).

[Synthesis and spectroscopic properties of tetra-(dimethylaminophenyl) porphyrin and its metal complexes].

Porphyrin and metalloporphyrin distribute widely in nature and they play an important role in the life. Synthesis of porphyrin compounds with special function has been the focus of attention. In the present paper, porphyrin and metalloporphyrin compound were synthesized by the following method: by one-step synthesis, tetra-(dimethylaminophenyl) porphyrin (T(DMAP) P) was synthesized with propionic acid, acetic acid and nitrobenzene as solvent and 4-dimethylaminobenzaldehyde and pyrrole as raw material.

[Study on spectral behavior of meso-tetra-(3, 5-dibromo-4-hydroxyphenyl) porphyrin with calf thymus DNA].

The binding characteristics of meso-tetra-(3, 5-dibromo-4-hydroxphenyl) porphyrin [T(DBHP)P] with calf thymus DNA (ct DNA) in pH 4.92 HAc-NaAc buffer solution were studied by the techniques of spectrophotometry. At the maxium absorption wavelength for T(DBHP)P, the decrease in the absorbance was linear with the amount of ct DNA.

[Study on the mechanism of interaction between TH-PF-Mo(VI) complex and bovine serum albumin by fluorimetric method].

The mechanism of interaction between bovine serum albumin (BSA) and trihydroxylphenylfluorone (TH-PF)-Mo(VI) complex in neutral solution was studied by fluorimetric method. The mechanism of fluorescence quenching of BSA caused by (TH-PF)-Mo(VI) complex probe was investigated and the binding constants under different temperature were measured. The binding constants of the reaction at 25 degrees C and 40 degrees C were calculated by fluorimetric method to be 4.

[Clinical pathology feature and prognostic factors of cervical lymph node metastases in hypopharyngeal carcinoma].

Objective: To investigate the risk clinicopathological factors of primary tumor in the prediction of cervical lymph node metastases and the cervical lymph node prognostic factors in hypopharyngeal squamous cell carcinoma.

Methods: A retrospective study was carried out to review the histopathological data from 98 hypopharyngeal squamous cell carcinoma patients. The relationship between histopathological parameters and cervical lymph node metastases were evaluated by means of a univariate chi2 test and multivariate stepwise logistic regression model.

Mesoporous spherical aggregates of anatase nanocrystals with wormhole-like framework structures: their chemical fabrication, characterization, and photocatalytic performance.

A facile and efficient approach for the fabrication of mesoporous spherical aggregates of anatase nanocrystals is reported in this paper. Cetyltrimethylammonium bromide was used as the structure-directing agent, and the interaction between cyclohexane microdroplets and the cetyltrimethylammonium bromide self-assemblies led to the assembly of 4-5-nm-sized anatase nanocrystals into spherical aggregates with mesoporous structures. The as-prepared anatase powders exhibited high photocatalytic activity and could be effectively used as the catalyst for the room-temperature photodegradation of a variety of organic dye pollutants in aqueous media including methyl orange, bromopyrogallol red, and methylene blue.

[Analysis of risk factors in the prediction of distant metastases of head and neck squamous cell carcinomas].

Objective: To investigate the risk factors related with distant metastases (DM) from head and neck squamous cell carcinomas (HNSCC).

Methods: A retrospective study was carried out to review the histopathological data from 532 HNSCC patients treated in Bethune International Peace Hospital from February 1978 to February 1998. The incidence and the risk factor for DM were evaluated in a model that included the following factors: sex, age, clinical staging, T and N staging, site of primary tumor, depth of primary tumor infiltration, histological grade of primary tumor, presence of cervical lymph node metastasis, number of positive neck nodes and levels involved, and presence of extracapsular nodal spread.