Severe acute respiratory syndrome (SARS) is caused by a coronavirus (SARS-CoV) and has the potential to threaten global public health and socioeconomic stability. Evidence of antibody-dependent enhancement (ADE) of SARS-CoV infection in vitro and in non-human primates clouds the prospects for a safe vaccine. Using antibodies from SARS patients, we identified and characterized SARS-CoV B-cell peptide epitopes with disparate functions. In rhesus macaques, the spike glycoprotein peptides S471-503, S604-625, and S1164-1191 elicited antibodies that efficiently prevented infection in non-human primates. In contrast, peptide S597-603 induced antibodies that enhanced infection both in vitro and in non-human primates by using an epitope sequence-dependent (ESD) mechanism. This peptide exhibited a high level of serological reactivity (64%), which resulted from the additive responses of two tandem epitopes (S597-603 and S604-625) and a long-term human B-cell memory response with antisera from convalescent SARS patients. Thus, peptide-based vaccines against SARS-CoV could be engineered to avoid ADE via elimination of the S597-603 epitope. We provide herein an alternative strategy to prepare a safe and effective vaccine for ADE of viral infection by identifying and eliminating epitope sequence-dependent enhancement of viral infection.

We herein report a new compound: 10-chloromethyl-11-demethyl-12-oxo-calanolide A (20, EC(50) = 7.4 nM, SI = 1417), which demonstrates a druggable profile with 32.7% oral bioavailability in rat, tolerated oral single dose toxicity in mice, and especially the feature of highly efficient suppression of the wild-type HIV-1 and Y181C mutant HIV-1 at an EC(50) = 7.4 nM and EC(50) = 0.46 nM, respectively.

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This study revealed the profiling of miRNAs in keloid that are potentially implicated in the development of this disease and could serve as novel diagnostic and therapeutic target of keloid.

Nucleotide-binding oligomerization domain-like receptors (NLRs) are intracellular sensors of pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs). Previously, we reported nucleotide-binding oligomerization domain-containing protein 1 (NOD1) antagonists (11, 12) and a NOD2 antagonist (9) that sensitized docetaxel (DTX) or paclitaxel (PTX) treatment for breast or lung cancer. In this article, we describe for the first time a 1,4-benzodiazepine-2,5-dione (BZD) derivative (26bh) that acts as a dual NOD1/NOD2 antagonist and inhibits both nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) inflammatory signaling, thereby sensitizing PTX to suppress Lewis lung carcinoma (LLC) growth. After investigation of the compound's cytotoxicity, a systematic structure-activity relationship (SAR) was completed and revealed several key factors that were necessary to maintain antagonistic ability. This study establishes the possibility for using adjuvant treatment to combat cancer by antagonizing both NOD1 and NOD2 signaling.

When mine water inrush accidents occur, timely and accurately identifying the water inrush source plays an important role in determining the cause of water inrush and making a solution to a disaster. According to the differences of water chemical composition in each water sources of mine, eight kinds of indicators of water chemical composition were selected as sample variables for water inrush source identification. On this basis, an identification model of water inrush source was established by using principal component analysis (PCA) and Fisher discriminant analysis (FDA) combined. The model was used to identify the water inrush source of 14 groups of training samples and 12 groups of samples to be judged in different water sources of the Xiandewang coal mine, and it was compared with the results of the conventional identification model which used the FDA method. Results of this study showed that having processed data by using the PCA method can effectively eliminate the effects of information superposition between sample indicators, and the identification accuracy of mine water inrush source was significantly increased. Related study in this paper can provide some basis and reference for the study of mine water inrush source identification technology.

A coordinating, copper-catalyzed direct α-C(sp 3 )−H fluorination method has been developed to prepare vital quaternary α-fluorinated α-amino acid derivatives. A Cu(II) catalytic SET oxidative addition mechanism is proposed, involving a key fluoride-coupled Cu(II) charge transfer complex. The protocol can tolerate a rich variety of α-amino acids, for which the auxiliary group is removed in high yield and substituted for the direct preparation of dipeptide derivatives with detachable, single absolute configurations of the target compounds.

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