Organo-Photoredox Catalyzed C(sp3)-H Bond Arylation of Aliphatic Amides.

A C(sp3)-H bond arylation of aliphatic amides has been achieved via organophotoredox catalysis. The reaction could be realized at room temperature with visible light source and metal-free catalyst. Quinuclidine is employed as an efficient HAT reagent and a range of aliphatic amides is employed as both substrate and solvent in the reaction. This photocatalyzed transformation provides a convenient protocol to afford a board range of N-benzyl amides.

An emergency nursing and monitoring procedure on cognitive impairment and neurological function recovery in patients with acute cerebral infarction.

BACKGROUND: The optimization and standardization of emergency nursing and monitoring procedures are of great significance for thrombolytic treatment of acute cerebral infarction. OBJECTIVE: Studies on the emergency nursing and monitoring procedure on cognitive impairment and neurological function in patients with acute cerebral infarction are still limited. METHODS: The study was a randomized controlled trial and 134 patients with acute cerebral infarction were recruited. They were randomly arranged into the control group (n = 67) receiving normal nursing procedure and the intervention group (n = 67) receiving emergency nursing and monitoring procedure after pre-intervention assessment. The cognitive impairment, neurological function and levels of inflammatory biomarkers and neuron-specific enolase of the participants were evaluated and analyzed. RESULTS: Emergency nursing and monitoring procedure improved Mini-mental State Examination and Montreal Cognitive Assessment scores of patients with cerebral infraction compared with the control group. It also improved the scores of National Institutes of Health Stroke Scale, activities of daily living scale, Fugl-Meyer scale in the participants. Emergency nursing and monitoring procedure led to significantly decreased neuron-specific enolase and inflammatory cytokines in the serum of the participants. CONCLUSION: Emergency nursing and monitoring procedure are beneficial for cognitive impairment and neurological function recovery in patients with acute cerebral infarction.

Visible-Light-Induced Catalyst-Free Carboxylation of Acylsilanes with Carbon Dioxide.

Intermolecular carbon-carbon bond formation between acylsilanes and carbon dioxide (CO2) was achieved by photoirradiation under catalyst-free conditions. In this reaction, siloxycarbenes generated by photoisomerization of the acylsilanes added to the C═O bond of CO2 to give α-ketocarboxylates, which underwent hydrolysis to afford α-ketocarboxylic derivatives in good yields. Control experiments suggest that the generated siloxycarbene is likely to be from the singlet state (S1) of the acylsilane and the addition to CO2 is not in a concerted manner.

Regioselective Crossed Aldol Reactions under Mild Conditions via Synergistic Gold-Iron Catalysis.

A synergistic gold/iron catalytic system was developed for sequential alkyne hydration and vinyl gold addition to aldehydes or ketones. Fe(acac)3 was identified as an essential co-catalyst in preventing vinyl gold protodeauration and facilitating nucleophilic additions. Effective C-C bond formation was achieved under mild conditions (r.t.) with excellent regioselectivity and high efficiency (1% [Au], up to 95% yields). Extending reaction scope to intramolecular fashion achieved successful macrocyclization (16-31 ring sizes) with excellent yields (up to 90%, gram-scale) without extended dilution (0.2 M), which highlighted the great potential of this new crossed-aldol strategy in challenging target molecule synthesis.

MiRNA-575 suppresses angiogenesis by targeting Rab5-MEK-ERK pathway in endothelial cells.

Hypertension is a major risk factor for the development of atherosclerosis. Increased carotid intima-media thickness (CIMT) is generally considered as an early marker of atherosclerosis. Recently, circulating miRNAs have been implicated both as sensitive biomarkers and key regulators in the development of atherosclerosis. However, the biological functions and molecular regulatory mechanisms for miR-575 on angiogenesis remain unknown. In our study, we first identified up-regulation of circulating miR-575 in plasma of essential hypertensive patients with increased CIMT (iCIMT) compared with those patients with normal CIMT (nCIMT). Furthermore, the overexpression of miR-575 in human umbilical vein endothelial cells (HUVECs) by its mimics significantly inhibited migration and proliferation as well as induction of apoptosis of HUVECs. Inhibition of miR-575 performed the reverse effects of HUVECs. We further suggested Rab5B was the downstream target of miR-575 and knockdown of Rab5B significantly inhibited migration and proliferation of HUVECs. Overexpression of Rab5B largely rescued the miR-575-mediated impairment of angiogenesis processes including: cell proliferation, migration, and apoptosis as well as activation of mitogen-activated protein kinase/extracellular signal-regulated kinase (MEK-ERK) signaling. Therefore, our results uncover a novel role of miR-575 in endothelial cells, implying a potential biomarker and clinical target for atherosclerosis in hypertensive patients.

Effects of arachidonic acid on the lysosomal ion permeability and osmotic stability.

In this study, we investigated the effects of arachidonic acid, a PLA2-produced lipid metabolite, on the lysosomal permeability, osmotic sensitivity and stability. Through the measurements of lysosomal beta-hexosaminidase free activity, membrane potential, intralysosomal pH, and lysosomal latency loss in hypotonic sucrose medium, we established that arachidonic acid could increase the lysosomal permeability to both potassium ions and protons, and enhance the lysosomal osmotic sensitivity. As a result, the fatty-acid-promoted entry of potassium ions into the lysosomes via K+/H+ exchange, which could produce osmotic imbalance across their membranes and osmotically destabilize the lysosomes. In addition, the enhancement of lysosomal osmotic sensitivity caused the lysosomes to become more liable to destabilization in osmotic shock. The results suggest that arachidonic acid may play a role in the lysosomal destabilization.