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The two‐step sequentially deposition strategy has been widely used to produce high‐performance FAPbI3‐based solar cells. However, due to the rapid reaction between PbI2 and FAI, a dense perovskite film forms on top of the PbI2 layer immediately and blocks the FAI diffusion into the bottom of the PbI2 film for a complete reaction, which results in a low‐efficiency and limited reproducibility of perovskite solar cells (PSCs). Here, high‐quality α‐FAPbI3 perovskite films by crystal growth regulation with 4‐fluorobenzamide additives is fabricated. The additives can interact with FAI to suppress the fast reaction between the FAI and PbI2 and effectively passivate the under‐coordinated Pb2+ or I‐ defects. As a result, α‐FAPbI3 perovskite films with low trap density and large grain size are prepared. The modified PSCs present a high‐power conversion efficiency of 24.08%, maintaining 90% of their initial efficiency after 1400 h in high humidity. This study provides an efficient strategy of synergistic crystallization and passivation to form high‐quality α‐FAPbI3 films for high‐performance PSCs. [ABSTRACT FROM AUTHOR]

BACKGROUND: Animal experiments have found that injection of angiogenic cells or growth factors into experimental animals significantly promotes the growth of collateral vessels. However, a large number of clinical randomized controlled trials, including administration of angiogenic cells to patients with severe lower limb ischemia or myocardial infarction, have been ineffective to restore the blood flow in ischemic tissues. By comparing the remarkable effects of animal experiments and disappointing clinical trial results, it may reflect a fact that young animals are used in most laboratories, while most of the patients with ischemic diseases are elderly. OBJECTIVE: To explore the effect of aging on the growth of collateral vessels in ischemic hind limbs in adult and aged rat models of femoral artery ligation. METHODS: Twelve healthy adult rats (6-month-old) were divided into adult sham group and adult ligation group, and 12 aged rats (20-month-old) were divided into aged sham group and aged ligation group. Rats in the ligation groups underwent femoral artery ligation. The rats survived for 1 week after surgery. Three rats in each group were taken and the muscles with collateral vessels in the hind limbs were taken for frozen section for immunofluorescence histochemical detection of endothelial nitric oxide synthase, Ki67 and matrix metalloproteinase 2. Another three rats from each group were subjected to angiography using gelatin trioxide and X-ray for observing the growth of collateral vessels. RESULTS AND CONCLUSION: Compared with the sham groups, rats in the ligation groups had more collateral vessels in hind limbs, increased number of Ki67-positive cells and increased expression of endothelial nitric oxide synthase and matrix metalloproteinase 2 (P < 0.01). Compared with the adult ligation group, the number of collateral vessels was less (P < 0.01), the number of Ki67 positive cells was reduced (P < 0.01), and the expression of endothelial nitric oxide synthase and matrix metalloproteinase 2 was significantly decreased in the aged ligation group (P < 0.01). Overall, aging impairs the growth of collateral vessels in ischemic hind limbs of rats. [ABSTRACT FROM AUTHOR]

The development of a nanographite (NG)‐based fluorescent biosensor for detecting microRNA (miRNA) is reported. Duplex‐specific nuclease (DSN)‐assisted signal amplification was key to its function. In the absence of a target, with the assistance of p‐stacking interactions, the NG adsorbed the double carboxyfluorescein (FAM)‐labelled probe (DFP) whose surface was perfectly complementary to miRNA, leading to quenching of FAM fluorescence. In the presence of a target, double‐stranded DNA/RNA hybrids were repelled by the NG and fluorescence was restored. Meanwhile, the considerable increase in signal strength and sensitivity suggests DSN‐mediated target recycling as an application. The detection limit of the proposed biosensor for miRNA was 10 pmol/L; there was a linear correlation when the miRNA concentration ranged from 50 pmol/L to 5 nmol/L. Additionally, the method could distinguish let‐7b from most let‐7 miRNA family members and was successfully used in a sample assay. This biosensor is a novel and highly sensitive tool for miRNA detection and has great potential for biochemical research, disease diagnosis, and therapy. [ABSTRACT FROM AUTHOR]

Neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD), are incurable diseases characterized by progressive loss of cognitive or motor function, which construct a serious threat to the life quality of aging populations and their life spans. Apelin is an endogenous ligand for the G protein‐coupled receptor. Apelin is reported to be detected not only in the cardiovascular system but also in neurons of the central nervous system (CNS). In addition, alterations in the expression level of apelin appear to play a pivotal role in various physiological processes including loss of structure or function of neurons, inflammatory responses, oxidative stress, Ca2+ signaling, apoptosis, and autophagy. All of these processes are intimately related to the occurrence of neurodegenerative diseases. Recently, apelin is reported to improve cognitive impairment in PD by antioxidant and antiapoptotic properties. Hence, it is becoming increasingly appreciated that altering the level of apelin can change the course or dictate the outcome of neurodegenerative events such as AD, PD, and HD, suggesting that apelin could be a potential target for the treatment of neurodegenerative diseases possibly acting on a variety of signaling pathways such as suppression of inflammatory responses, inhibition of oxidative stress, reduction of Ca2+ signaling, induction of autophagy, and suppression of apoptosis. [ABSTRACT FROM AUTHOR]

Acute ischemic brain injury is a cerebrovascular disease with high clinical incidence. An increasing number of preclinical evidence has verified the complex interaction between autophagy disorder and mitochondrial damage. Endoplasmic reticulum stress, oxidative stress and excessive neuroinflammation are the main mechanisms of the neural injury induced by acute cerebral ischemia-reperfusion injury. Apelin and its receptors are widely distributed in various tissues and organs in the human body. Increasing evidence has suggested that apelin has a neuroprotective effect against excitatory toxicity injury, oxidative stress injury and induction of neuronal apoptosis, and it can play a neuroprotective role after acute cerebral ischemia-reperfusion injury. This review summarizes the progress of the neuroprotective effects and mechanisms of apelin, aiming to provide evidence for its therapeutic potential., Competing Interests: None., (AJTR Copyright © 2022.)

The development of a nanographite (NG)-based fluorescent biosensor for detecting microRNA (miRNA) is reported. Duplex-specific nuclease (DSN)-assisted signal amplification was key to its function. In the absence of a target, with the assistance of p-stacking interactions, the NG adsorbed the double carboxyfluorescein (FAM)-labelled probe (DFP) whose surface was perfectly complementary to miRNA, leading to quenching of FAM fluorescence. In the presence of a target, double-stranded DNA/RNA hybrids were repelled by the NG and fluorescence was restored. Meanwhile, the considerable increase in signal strength and sensitivity suggests DSN-mediated target recycling as an application. The detection limit of the proposed biosensor for miRNA was 10 pmol/L; there was a linear correlation when the miRNA concentration ranged from 50 pmol/L to 5 nmol/L. Additionally, the method could distinguish let-7b from most let-7 miRNA family members and was successfully used in a sample assay. This biosensor is a novel and highly sensitive tool for miRNA detection and has great potential for biochemical research, disease diagnosis, and therapy., (© 2019 John Wiley & Sons, Ltd.)