[A new naphthalene derivative from Aloe vera and its antibacterial activity].

A new naphthalene derivative has been isolated from Aloe vera by using various chromatographic techniques, including silica gel, sephadex, MCI-gel resin, and RP-HPLC. The new compound was determined as 3-hydroxy-1-(1,7-dihydroxy-3,6-dimethoxynaphthalen-2-yl)propan-1-one (1). In the biological activity assay, compound 1 disglayed prominent antibacterial activity with a MIC90 value of (48±4) mg•L⁻¹ for methicillin resistant Staphylococcus aureus (MRSA) strain which was stronger than that of the positive control levofloxacin with a MIC90 value (58±5) mg•L⁻¹.

Diagnostic Value of Dual-Energy CT Virtual Noncalcium for the Assessment of Bone Marrow Edema of Wrist in Patients with Rheumatoid Arthritis.

RATIONALE AND OBJECTIVES: To evaluate the value of dual-energy CT (DECT) virtual noncalcium (VNCa) images in the diagnosis of wrist bone marrow edema (BME) in patients with rheumatoid arthritis (RA). MATERIALS AND METHODS: 43 patients with wrist involvement in active RA prospectively underwent DECT and MRI. Functional DECT images reconstruction yielded VNCa images. MRI served as the reference standard for diagnosing BME. BME diagnosis differences between VNCa images and MRI were compared. Differences in CT values between BME and normal bone marrow were assessed. The optimal CT value for detecting BME in VNCa images was determined through ROC curve analysis. The correlation between VNCa images scores and RA disease activity was evaluated. RESULTS: There was a high agreement between VNCa images and MRI in diagnosing BME (Kappa=0.831). VNCa images showed a significant difference in CT values between BME and normal bone marrow (P < 0.001). A cut-off value of - 54.8 HU yielded a sensitivity, specificity, and accuracy of 90.72%, 94.30%, and 93.33%, respectively, for detecting BME on VNCa images. The area under the ROC curve was 0.937 for distinguishing BME from normal bone marrow. Conventional CT images showed no statistically significant difference (P = 0.174) in CT values between BME and normal bone marrow. The VNCa images BME scores were positively correlated with RA disease activity (r = 0.399). CONCLUSION: The DECT VNCa technique demonstrates its potential for diagnosing wrist BME in patients with RA and provides a valuable tool for assessing disease activity in RA. IMPORTANT FINDINGS: The DECT VNCa technique has the ability to distinguish between BME and normal bone marrow. The VNCa images BME scores were positively correlated with the disease activity in RA.

Overexpression of NtLHT1 affects the development of leaf morphology and abiotic tolerance in tobacco.

LYSINE HISTIDINE TRANSPORTER1 (LHT1) is a crucial broad-specificity and high-affinity amino acid transporter affecting the uptake of nitrogen and probably the tolerance to abiotic stress in plants. However, little is known about the phenotypic functions of LHT1 in plant growth and development and abiotic stress tolerance. In this study, we identified the NtLHT1 gene from the tobacco variety Honghuadajinyuan (HD) and determined its important roles in leaf morphological development and plant resistance to abiotic stress. Comprehensive functional analyses using knockout and overexpression transgenic lines (ntlht1 and OE) revealed overexpression of NtLHT1 accelerated leave senescence and increased plant height, leaf number and plant tolerance under cold, salt and drought stresses. In addition, NtLHT1 overexpression significantly decreased the leaf elongation of HD, causing the leaves to change from a long-elliptical shape to an elliptical shape. However silencing NtLHT1 decreased the seed germination rate under NaCl and PEG stresses. Moreover, NtLHT1 significantly affected the contents of various amino acids, such as the neutral, acidic, non-polar and aromatic amino acids, ethylene precursor (ACC), GA3 and IAA in tobacco. These results suggested that the amino acid and ethylene precursor ACC transport activities of NtLHT1 provide fine regulatory function for plant growth and development and plant tolerance to abiotic stress.

Loss function of NtGA3ox1 delays flowering through impairing gibberellins metabolite synthesis in Nicotiana tabacum.

Flowering time, plays a crucial role in tobacco ecological adaptation besides its substantial influence on tobacco production and leaf quality. Meanwhile, it is sensitive to biotic or abiotic challenges. The plant hormones Gibberellins (GAs), controlling a number of metabolic processes, govern plants growth and development. In this study, we created a late flowering mutant HG14 through knocking out NtGA3ox1 by CRISPR/Cas9. It took around 13.0 and 12.1 days longer to budding and flowering compared to wild type Honghuadajinyuan. Nearly all of the evaluated agronomic characters deteriorated in HG14, showing slower growth and noticeably shorter and narrower leaves. We found that NtGA3ox was more prevalent in flowers through quantitative reverse transcription PCR analysis. Transcriptome profiling detected 4449, 2147, and 4567 differently expressed genes at the budding, flowering, and mature stages, respectively. The KEGG pathway enrichment analysis identified the plant-pathogen interaction, plant hormone signal transduction pathway, and MAPK signaling pathway are the major clusters controlled by NtGA3ox1 throughout the budding and flowering stages. Together with the abovementioned signaling pathway, biosynthesis of monobactam, metabolism of carbon, pentose, starch, and sucrose were enriched at the mature stage. Interestingly, 108 up- and 73 down- regulated DEGs, impairing sugar metabolism, diterpenoid biosynthesis, linoleic and alpha-linolenic acid metabolism pathway, were continuously detected accompanied with the development of HG14. This was further evidenced by the decreasing content of GA metabolites such as GA4 and GA7, routine chemicals, alkaloids, amino acids, and organic acids Therefore, we discovered a novel tobacco flowering time gene NtGA3ox1 and resolved its regulatory network, which will be beneficial to the improvement of tobacco varieties.

The complete chloroplast genome sequence of Camellia rostrata S. X. Yang & S. F. Chai (Theaceae), a critically endangered yellow camellia from southwest China.

Camellia rostrata S. X. Yang & S. F. Chai is a recently described yellow camellia species from Guangxi, China. It is a critically endangered species according to the IUCN Red List Categories and Criteria. Here, we report the complete chloroplast (cp) genome based on next-generation sequencing technology. The complete cp genome of C. rostrata is 156,547 bp in length and consists of a large single-copy (LSC, 86,199 bp) region, a small single-copy (SSC, 18,204 bp) region, and a pair of inverted repeats (IRs, 26,072 bp). The genome contains 135 genes including 40 tRNA, eight rRNA, and 87 protein-coding genes. Phylogenetic analysis resolved C. rostrata in a clade containing C. huana and C. impressinervis, both of which are classified to Camellia sect. Archecamellia. Our findings support the placement of C. rostrata in C. sect. Archecamellia as proposed by a previous study. The cp genome of C. rostrata provides valuable bioinformatic resources for the protection and utilization of this yellow camellia species.

Indigenous knowledge of dye-yielding plants among Bai communities in Dali, Northwest Yunnan, China.

BACKGROUND: Bai people in the Dali Prefecture of Northwest Yunnan, China, have a long history of using plant extracts to dye their traditional costumes and maintain this culture for posterity. However, the development of modern technology, while vastly improving the dyeing efficiency, is also replacing indigenous knowledge which threatens the indigenous practice, causing the latter disappearing gradually. This study sought to examine the indigenous knowledge of plants used for textile dyeing in Bai communities, so as to provide a foundation for their sustainable development. METHODS: We conducted a semi-structured interview among 344 informants (above age 36) selected through a snowball sampling method. Free lists and participant observation were used as supplementary methods for the interviews. Three quantitative indicators (informant consensus factor [ICF], use frequency, and cultural importance index [CI]) were used to evaluate the indigenous knowledge of the dye-yielding plants. RESULTS: Twenty-three species belonging to 19 plant taxonomic families were used for dye by Bai communities. We summarized them into four life forms, eight used parts, five colors, three processing methods, and four dyeing methods. Among them, Strobilanthes cusia (Nees) O. Kuntze was the most traditional dyeing plant and has an important cultural value. Location, age, and gender were found to have a significant effect on indigenous knowledge, and the dyeing knowledge was dynamic and influenced by social factors. CONCLUSIONS: Diverse plant resources and rich indigenous knowledge of textile dyeing persist at settlements of Bai communities in Dali Prefecture. However, high labor costs and thinning market of traditional products that use plant dye cause repulsion toward traditional practice. To that, a good income in other profession attracts indigenous people to shift from their tradition of making plant-based dye and associated cultural systems at risk of extinction. More research for market development for products that use plant-based dye is necessary for the conservation of this valuable knowledge and biodiversity protection in Bai communities.

Six new physalins from Physalis alkekengi var. franchetii and their cytotoxicity and antibacterial activity.

Six new physalin steroids, 7ß-methoxylisophysalin B (1), 7ß-methoxylphysalin C (2), physalin V (3), physalin VI (4), physalin VII (5), isophysalin I (6), together with 20 known physalins (7-26) were isolated from calyces of Physalis alkekengi var. franchetii. Structures of the new compounds were revealed through 1D and 2D NMR and mass spectroscopic methods. Compounds 1-26 were evaluated for cytotoxicity against human HL-60, SMMC-7721, A-549, MCF-7 and SW-480, and the results indicated that compounds 8, 11, and 14 displayed potent cytotoxicities (IC50<5µM) in vitro. Further antibacterial assay indicated that compounds 8, 14, and 19 showed high antibacterial activities against Bacillus subtilis and Escherichia coli.

[Pyrolysis of the Lysimachia foenum-graecum Hance extract by online pyrolysis-gas chromatography-mass spectrometry].

In order to study the pyrolytic properties of Lysimachia foenum-graecum Hance extract, it was pyrolysed and detected by online pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). The pyrolytic experimental conditions were designed to simulate the real combustion conditions inside a burning cigarette. The sample was heated at 30 degrees C/s from 300 to 900 degrees C (held for 5 s) under the flow of 9% oxygen in nitrogen. The pyrolytic components and volatile components were compared. The results showed that 64 pyrolytic components were detected, with 88.27% of the total peak area, including linoleic acid ethyl ester (10.33%), hexadecanoic acid, ethyl ester (9.12%), 9,12,15-octadecatrienoic acid, (Z,Z,Z) - (8.03%), 2-furan-carboxaldehyde, 5-(hydroxymethyl) - (6.02%), neophytadiene (5.12%), heptadecanoic acid, ethyl ester (4.50%), acetic acid, phenyl ester (3.51%), 5-methoxy-2, 2-di-methylindan-1-one (2.73%). The number of pyrolytic components was more than that of the volatile components, and 20 components were identified in both pyrolytic components and volatile components, including higher fatty acids and their esters, neophytadiene, 2-furancarboxaldehyde, (hydroxymethyl)-, and 2 (5H)-furanone, 3-hydroxy-4, 5-dimethyl-. The on-line pyrolysis was similar to the real cigarette combustion conditions. The method is a simple, rapid and good qualitative method for the pyrolysis.