Direct and selective synthesis of primary amines from easily available precursors is attractive yet challenging. Herein, we report the rapid synthesis of primary amines from alkenes via metal‐free ...regioselective hydroamination at room temperature. Ammonium carbonate was used as ammonia surrogate for the first time, allowing for efficient conversion of terminal and internal alkenes into linear, α‐branched, and α‐tertiary primary amines under mild conditions. This method provides a straightforward and powerful approach to a wide spectrum of advanced, highly functionalized primary amines which are of particular interest in pharmaceutical chemistry and other areas.
A straightforward and modular route to a wide variety of aliphatic primary amines from alkenes is presented based on a metal‐free hydroamination at room temperature. The use of cost‐effective and easily available ammonium carbonate allows for the efficient conversion of terminal and internal alkenes with diverse substitution patterns into highly functionalized linear, α‐branched, and α‐tertiary primary amines.
Summary
Plants form complex interaction networks with diverse microbiomes in the environment, and the intricate interplay between plants and their associated microbiomes can greatly influence ...ecosystem processes and functions. The phyllosphere, the aerial part of the plant, provides a unique habitat for diverse microbes, and in return the phyllosphere microbiome greatly affects plant performance. As an open system, the phyllosphere is subjected to environmental perturbations, including global change, which will impact the crosstalk between plants and their microbiomes. In this review, we aim to provide a synthesis of current knowledge of the complex interactions between plants and the phyllosphere microbiome under global changes and to identify future priority areas of research on this topic.
Aliphatic trifluoromethyl ketones are a type of unique fluorine-containing subunit which plays a significant role in altering the physical and biological properties of molecules. However, catalytic ...methods to provide direct access to aliphatic trifluoromethyl ketones is highly desirable yet remains underdeveloped, partially due to the high reactivity and instability of trifluoroacetyl radical. Herein, we report a photocatalytic synthesis of trifluoromethyl ketones from alkyl bromides with trifluoroacetic anhydride. The reaction features a dual catalysis of visible-light and XAT reaction, followed by an enabling radical-radical cross-coupling of alkyl radical with a stabilized trifluoromethyl radical. The reaction provides the first straightforward access to aliphatic trifluoromethyl ketones from easily-available and cost-effective alkyl halides and TFAA.
Direct alkylation of the C−H bond arenes in a selective manner is a long‐standing challenge. Herein, a metal‐free photocatalytic regioselective C−H alkylation method for electron‐rich arenes with ...both activated and unactivated alkenes was developed. The reaction tolerates a wide range of aromatic rings with diverse substitution patterns, as well as terminal and internal alkenes, providing a general and straightforward metal‐free method for C−C bond formation from inert C−H bonds. Moreover, alkynes are also compatible to give the C−H vinylation of electron‐rich arenes.
Herein, a metal‐free photocatalyzed site‐ and regioselective C−H alkylation of electron‐rich arenes at room temperature using alkenes as the alkylating reagents is described for the first time. The alkylation proceeds in the absence of any directing groups, and tolerates both activated and unactivated alkenes to deliver alkylated arenes with broad functional‐group tolerance, providing an alternative to the classical Friedel–Crafts alkylation reaction.
Climate change globally affects soil microbial community assembly across ecosystems. However, little is known about the impact of warming on the structure of soil microbial communities or underlying ...mechanisms that shape microbial community composition in subtropical forest ecosystems. To address this gap, we utilized natural variation in temperature via an altitudinal gradient to simulate ecosystem warming. After 6 years, microbial co‐occurrence network complexity increased with warming, and changes in their taxonomic composition were asynchronous, likely due to contrasting community assembly processes. We found that while stochastic processes were drivers of bacterial community composition, warming led to a shift from stochastic to deterministic drivers in dry season. Structural equation modelling highlighted that soil temperature and water content positively influenced soil microbial communities during dry season and negatively during wet season. These results facilitate our understanding of the response of soil microbial communities to climate warming and may improve predictions of ecosystem function of soil microbes in subtropical forests.
Climate change globally affects soil microbial community assembly across ecosystems. We utilized natural variation in temperature via an altitudinal gradient to simulate ecosystem warming. After 6 years of experiment, microbial co‐occurrence network complexity increased with warming, and changes in their taxonomic composition were asynchronous due to contrasting community assembly processes. Structural equation modelling highlighted that soil temperature and water content positively influenced soil microbial communities during dry season and negatively during wet season.
Hair follicle stem cells (HFSCs) are among the most widely available resources and most frequently approved model systems used for studying adult stem cells. HFSCs are particularly useful because of ...their self-renewal and differentiation properties. Additionally, the cyclic growth of hair follicles is driven by HFSCs. There are high expectations for the use of HFSCs as favourable systems for studying the molecular mechanisms that contribute to HFSC identification and can be applied to hair loss therapy, such as the activation or regeneration of hair follicles, and to the generation of hair using a tissue-engineering strategy. A variety of molecules are involved in the networks that critically regulate the fate of HFSCs, such as factors in hair follicle growth and development (in the Wnt pathway, Sonic hedgehog pathway, Notch pathway, and BMP pathway), and that suppress apoptotic cues (the apoptosis pathway). Here, we review the life cycle, biomarkers and functions of HFSCs, concluding with a summary of the signalling pathways involved in HFSC fate for promoting better understanding of the pathophysiological changes in the HFSC niche. Importantly, we highlight the potential mechanisms underlying the therapeutic targets involved in pathways associated with the treatment of hair loss and other disorders of skin and hair, including alopecia, skin cancer, skin inflammation, and skin wound healing.
Background/Aims: The rejuvenation properties of nanofat grafting have been described in recent years. However, it is not clear whether the clinical efficacy of the procedure is attributable to stem ...cells or linked to other components of adipose tissue. In this study we isolated nanofat-derived stem cells (NFSCs) to observe their biological characteristics and evaluate the efficacy of precise intradermal injection of nanofat combined with platelet-rich fibrin (PRF) in patients undergoing facial rejuvenation treatment. Methods: Third-passage NFSCs were isolated and cultured using a mechanical emulsification method and their surface CD markers were analyzed by flow cytometry. The adipogenic and osteogenic nature and chondrogenic differentiation capacity of NFSCs were determined using Oil Red O staining, alizarin red staining, and Alcian blue staining, respectively. Paracrine function of NFSCs was evaluated by enzyme-linked immunosorbent assay (ELISA) at 1, 3, 7, 14, and 28 days after establishing the culture. Then, the effects of PRF on NFSC proliferation were assessed in vitro. Finally, we compared the outcome in 103 patients with facial skin aging who underwent both nanofat and intradermal PRF injection (treatment group) and 128 patients who underwent hyaluronic acid (HA) injection treatment (control group). Outcomes in the two groups were compared by assessing pictures taken at the same angle before and after treatment, postoperative recovery, incidence of local absorption and cysts, and skin quality before treatment, and at 1, 12, 24 months after treatment using the VISIA Skin Image Analyzer and a SOFT5.5 skin test instrument. Results: NFSCs expressed CD29, CD44, CD49d, CD73, CD90, and CD105, but did not express CD34, CD45, and CD106. NFSCs also differentiated into adipocytes, osteoblasts, and chondrocytes under appropriate induction conditions. NFSCs released large amounts of growth factors such as VEGF, bFGF, EGF, and others, and growth factor levels increased in a time-dependent manner. At the same time, PRF enhanced proliferation of NFSCs in vitro in a dose-dependent manner, and the growth curves under different concentrations of PRF all showed plateaus 6d after seeding. Facial skin texture was improved to a greater extent after combined injection of nanofat and PRF than after control injection of HA. The nanofat-PRF group had a higher satisfaction rate. Neither treatment caused any complications such as infection, anaphylaxis, or paresthesia during long-term follow-up. Conclusion: NFSCs demonstrate excellent multipotential differentiation and paracrine function, and PRF promotes proliferation of NFSCs during the early stage after seeding. Both nanofat-PRF and HA injection improve facial skin status without serious complications, but the former was associated with greater patient satisfaction, implying that nanofat-PRF injection is a safe, highly effective, and long-lasting method for skin rejuvenation.
Background
Controversy still exists in which subtype of non-small-cell lung cancer squamous cell carcinoma (SCC) or adenocarcinoma is more likely to have lymph node (LN) metastasis. The aim of this ...study is to compare the pattern of LN metastasis in two cohorts of matched patients surgically treated for SCC or adenocarcinoma.
Methods
A retrospective analysis of patients undergoing lobectomy or segmentectomy with systematic lymphadenectomy without preoperative treatment for lung SCC or adenocarcinoma was conducted in this study. Data for analysis consisted of age, gender, tumor size, lobe-specific tumor location, tumor location (peripheral or central), and pathologic findings. We conducted the propensity score-matched (PSM) analysis to eliminate potential bias effects of possible confounding factors.
Results
From January 2015 to December 2016 in our department, we finally included a total of 387 patients (including 63 patients with SCC and 324 patients with adenocarcinoma) for analysis. For the unmatched cohort, there was no sufficient evidence of significantly different number of positive LNs (
P
= 0.90) and rate of LN metastasis (
P
= 0.23) between SCC patients and adenocarcinoma patients. However, potential confounding factors, for example gender, tumor size, tumor location, tumor differentiation, and total number of dissected LNs, were significantly different between patients with SCC and those with adenocarcinoma. In the analysis of matched cohort after PSM analysis, those above confounding factors were comparable between the two groups. However, patients with adenocarcinoma had significantly more mean positive LNs (2.2 and 0.7;
P
= 0.008) and a higher rate of LN metastasis (53% and 29%;
P
= 0.016) than those with SCC.
Conclusions
Lung adenocarcinoma had a higher risk of LN metastasis than SCC, suggesting that different therapeutic modalities may be indicated for the two different subtypes of lung cancer.
Microglial activation plays an important role in neurodegenerative diseases by producing several proinflammatory enzymes and proinflammatory cytokines. The phenolic glucoside gastrodin, a main ...constituent of a Chinese herbal medicine, has been known to display anti-inflammatory properties. The current study investigates the potential mechanisms whereby gastrodin affects the expression of potentially pro-inflammatory proteins by cultured murine microglial BV-2 cells stimulated with lipopolysaccharide (LPS).
BV-2 cells were pretreated with gastrodin (30, 40, and 60 µM) for 1 h and then stimulated with LPS (1 µg/ml) for another 4 h. The effects on proinflammatory enzymes, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and proinflammatory cytokines, tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β), are analysed by double-immunofluorescence labeling and RT-PCR assay. To reveal the mechanisms of action of gastrodin we investigated the involvement of mitogen-activated protein kinases (MAPKs) cascades and their downstream transcription factors, nuclear factor-κB (NF-κB) and cyclic AMP-responsive element (CRE)-binding protein (CREB). Gastrodin significantly reduced the LPS-induced protein and mRNA expression levels of iNOS, COX-2, TNF-α, IL-1β and NF-κB. LPS (1 µg/ml, 30 min)-induced phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun N-terminal protein kinase (JNK) and p38 mitogen-activated protein kinase (p38 MAPK) and this was inhibited by pretreatment of BV-2 cells with different concentrations of gastrodin (30, 40, and 60 µM). In addition, gastrodin blocked LPS-induced phosphorylation of inhibitor κB-α (IκB-α) (and hence the activation of NF-κB) and of CREB, respectively.
This study indicates that gastrodin significantly attenuate levels of neurotoxic proinflammatory mediators and proinflammatory cytokines by inhibition of the NF-κB signaling pathway and phosphorylation of MAPKs in LPS-stimulated microglial cells. Arising from the above, we suggest that gastrodin has a potential as an anti-inflammatory drug candidate in neurodegenerative diseases.
Display omitted
•Manure application impacted the resistome in soil, earthworms and phyllosphere.•Manure with reduced antibiotic burden reduced the spread of the antibiotic resistome.•Shared ARGs and ...OTUs were founded within soil-earthworm-phyllosphere system.
The overuse of antibiotics in animal husbandry is widespread and believed to significantly contribute to the selection of antibiotic resistance genes (ARGs) in animals. Thus, there is a global drive to reduce antibiotic use in the agricultural sector. However, it has not been established whether a reduction in the use of antibiotics in livestock production would be effective in reducing the spread of ARGs. A microcosm approach was used to determine how the addition of manure with either reduced antibiotic levels or with typical antibiotic levels could affect the spread of antibiotic resistance genes between soil, earthworms and the phyllosphere. When compared to the control soil, earthworm and phyllosphere samples had the greater increase in ARG abundance in conventional manure treatments (P < 0.05). Reduced antibiotic manure also enriched the abundance of ARGs in the phyllosphere and soil but not earthworm guts when compared to the control (P < 0.05). In both soil and earthworm guts, the enrichment of ARGs was lower in reduced antibiotic manure than in conventional manure. This study has identified bacterial transfer through the soil-earthworm-phyllosphere system as a potential means to spread ARGs between habitats after fertilization with livestock derived manures.
PDF
