Abstract: A method for determining tobacco-specific nitrosamines (TSNAs) in cigarette smoke using one-step clean-up coupled with LC-MS/MS is provided, including the following steps: collecting a particulate matter of mainstream cigarette smoke with a Cambridge filter pad, mixing the particulate matter of mainstream cigarette smoke, an internal standards solution and water in a 50 mL plastic centrifuge tube, and vortexing the resulting mixture at room temperature to allow extraction; transferring an extraction solution after filtration to a new centrifuge tube, adding dichloromethane, and vortexing the resulting mixture; centrifuging to collect a dichloromethane extraction solution in a lower layer to another centrifuge tube, and placing the centrifuge tube in a water bath to remove dichloromethane; dissolving the resulting extraction solution in water, and transferring the resulting solution to an autosampler vial for LC-MS/MS analysis.

Abstract: A method for determining tobacco-specific nitrosamines (TSNAs) in tobacco using one-step clean-up coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) is provided, including the following steps: destemming flue-cured tobacco or sun-cured tobacco, drying, milling, and passing through a sieve; mixing the resulting tobacco, an internal standards solution and water in a plastic centrifuge tube, and vortexing the resulting mixture at room temperature to allow extraction; transferring an extraction solution after filtration to a new centrifuge tube, adding dichloromethane, and vortexing the resulting mixture; centrifuging to collect a dichloromethane extraction solution in a lower layer to another centrifuge tube, and placing the centrifuge tube in a water bath to remove dichloromethane; dissolving the resulting extraction solution in water, and transferring the resulting solution to an autosampler vial for LC-MS/MS analysis.

Abstract: The present invention “A Molecular marker Nicotine Associated SNP 1 for identifying high or nicotine content of tobacco and its kit as well as use thereof” belongs to field of molecular biology technology. The molecular marker Nicotine Associated SNP 1 is a SNP Nitab4.5_0002539:95304 A/G at base No. 95304 of Genomic segment No. 0002539 in tobacco genome version of Nitab v4.5 Genome Scaffolds Edwards2017. The present invention can accurately identify and screen tobacco germplasm resources with high or low nicotine content, and the screened tobacco can be directly used for breeding new tobacco varieties without transgenic methods. At the same time, gene sequence where the SNP site is located can also significantly activate promoters of key enzyme genes in nicotine synthesis pathway.

Abstract: A tobacco arsenic transport gene NtNIP7-1 and a cloning method and application thereof are disclosed. A nucleotide sequence of the tobacco arsenic transport gene NtNIP7-1 is shown as SEQ ID: No. 1, and an encoded amino acid sequence thereof is shown as SEQ ID: No. 2. The cloning method of the tobacco arsenic transport gene NtNIP7-1 includes (S1) extracting RNA in tobacco, performing reverse transcription, and obtaining a first-strand cDNA; and (S2) taking the first-strand cDNA obtained by the reverse transcription as a template, synthesizing a specific primer according to sequences of the NtNIP7-1 gene, performing PCR amplification, recovering and purifying a product of the PCR amplification, and sequencing. In the present invention, inhibition of the expression of the tobacco endogenous gene NtNIP7-1 in tobacco plants is able to significantly reduce the arsenic content of tobacco leaves, and has broad application prospects in the field of low arsenic content breeding.

Abstract: A tobacco arsenic transport gene NtNIP7-1 and a cloning method and application thereof are disclosed. A nucleotide sequence of the tobacco arsenic transport gene NtNIP7-1 is shown as SEQ ID: No. 1, and an encoded amino acid sequence thereof is shown as SEQ ID: No. 2. The cloning method of the tobacco arsenic transport gene NtNIP7-1 includes (S1) extracting RNA in tobacco, performing reverse transcription, and obtaining a first-strand cDNA; and (S2) taking the first-strand cDNA obtained by the reverse transcription as a template, synthesizing a specific primer according to sequences of the NtNIP7-1 gene, performing PCR amplification, recovering and purifying a product of the PCR amplification, and sequencing. In the present invention, inhibition of the expression of the tobacco endogenous gene NtNIP7-1 in tobacco plants is able to significantly reduce the arsenic content of tobacco leaves, and has broad application prospects in the field of low arsenic content breeding.

Abstract: Embodiments of the present disclosure provide for ?-AApeptides, ?-AApeptide building blocks, methods of making ?-AApeptides and libraries of ?-AApeptides, methods of screening the ?-AApeptide libraries for desired peptidomimetic activity, and the like. The present disclosure also provides for ?-AApeptides that are inhibitors of A? peptide aggregation, methods of inhibiting and disassembling A? peptide aggregation, methods of inhibiting the toxicity of A? aggregates towards N2a neuroblasotma cells, as well as methods and compounds for treating Alzheimer's disease.

Abstract: Embodiments of the present disclosure provide for ?-AApeptides, ?-AApeptide building blocks, methods of making ?-AApeptides and libraries of ?-AApeptides, methods of screening the ?-AApeptide libraries for desired peptidomimetic activity, and the like. The present disclosure also provides for ?-AApeptides that are inhibitors of A? peptide aggregation, methods of inhibiting and disassembling A? peptide aggregation, methods of inhibiting the toxicity of A? aggregates towards N2a neuroblasotma cells, as well as methods and compounds for treating Alzheimer's disease.

Abstract: Embodiments of the present disclosure provide for ?-AApeptides, ?-AApeptide building blocks, methods of making ?-AApeptides and libraries of ?-AApeptides, methods of screening the ?-AApeptide libraries for desired peptidomimetic activity, and the like. The present disclosure also provides for ?-AApeptides that are inhibitors of A? peptide aggregation, methods of inhibiting and disassembling A? peptide aggregation, methods of inhibiting the toxicity of A? aggregates towards N2a neuroblasotma cells, as well as methods and compounds for treating Alzheimer's disease.

Abstract: Embodiments of the present disclosure provide for ?-AApeptides, ?-AApeptide building blocks, methods of making ?-AApeptides and libraries of ?-AApeptides, methods of screening the ?-AApeptide libraries for desired peptidomimetic activity, and the like. The present disclosure also provides for ?-AApeptides that are inhibitors of A? peptide aggregation, methods of inhibiting and disassembling A? peptide aggregation, methods of inhibiting the toxicity of A? aggregates towards N2a neuroblasotma cells, as well as methods and compounds for treating Alzheimer's disease.

Abstract: A hypodermic needle assembly and a method of delivering a microsphere drug. A hypodermic needle assembly includes an injection needle; an injection device; and a hub defining a cavity including a transition portion having a first end and a second end between the first end and an inlet of the injection needle and having a gradually decreasing diameter from the first end to the second end, wherein the hub is coupled between the injection needle and the injection device such that the first end is in fluidic communication with an outlet of the injection device and the second end is in fluidic communication with the inlet of the injection needle, wherein the diameter of the cavity at the first end is larger than an outlet diameter of the injection device, and wherein the diameter at the second end is substantially the same as an inlet diameter of the injection needle.

Abstract: Pharmaceutical compositions of zopiclone [(6-(5-chloro-2-pyridyl)-5-[(4-methyl-1-piperazinyl)carbonyloxy]-7-oxo-6,7-dihydro-5H-pyrrolo[3,4-b]pyrazine)] that render the aqueous solubility/dissolution of the free base independent of the pH of the gastrointestinal tract are disclosed. The compositions are useful for oral administration.