Engineering of NEMO as calcium indicators with large dynamics and high sensitivity.

Genetically encoded calcium indicators (GECIs) are indispensable tools for real-time monitoring of intracellular calcium signals and cellular activities in living organisms. Current GECIs face the challenge of suboptimal peak signal-to-baseline ratio (SBR) with limited resolution for reporting subtle calcium transients. We report herein the development of a suite of calcium sensors, designated NEMO, with fast kinetics and wide dynamic ranges (>100-fold). NEMO indicators report Ca2+ transients with peak SBRs around 20-fold larger than the top-of-the-range GCaMP6 series. NEMO sensors further enable the quantification of absolution calcium concentration with ratiometric or photochromic imaging. Compared with GCaMP6s, NEMOs could detect single action potentials in neurons with a peak SBR two times higher and a median peak SBR four times larger in vivo, thereby outperforming most existing state-of-the-art GECIs. Given their high sensitivity and resolution to report intracellular Ca2+ signals, NEMO sensors may find broad applications in monitoring neuronal activities and other Ca2+-modulated physiological processes in both mammals and plants.

Langmuir-Blodgett Film Formed by Amphiphilic Molecules for Facile and Rapid Construction of Zinc-Iodine Cell.

Zinc-iodine batteries (ZIBs) are promising candidates for ecofriendly, safe, and low-cost energy storage systems, but polyiodide shuttling and the complex cathode fabrication procedures have severely hindered their broader commercial usage. Herein, a protocol is developed using phospholipid-like oleylamine molecules for scalable production of Langmuir-Blodgett films, which allows the facile preparation of ZIB cathodes in less than 1 min. The resulting inhomogeneous cathode allows for the continuous conversion of iodine. Moreover, the amine group of the oleylamine molecule at the cathode is capable of producing [OA*I+]I3- charge-transfer complexes with iodine, which facilitates the rapid migration of iodine and results in a highly reversible iodine conversion process. Consequently, the as-prepared ZIBs can deliver over 2000 cycles at 0.5 mA cm-2 with a capacity retention of 75.3%. This work presents a novel, straightforward, and efficient method for the rapid construction of ZIBs.

Molecular mechanisms of tumor resistance to radiotherapy.

BACKGROUND: Cancer is the most prevalent cause of death globally, and radiotherapy is considered the standard of care for most solid tumors, including lung, breast, esophageal, and colorectal cancers and glioblastoma. Resistance to radiation can lead to local treatment failure and even cancer recurrence. MAIN BODY: In this review, we have extensively discussed several crucial aspects that cause resistance of cancer to radiation therapy, including radiation-induced DNA damage repair, cell cycle arrest, apoptosis escape, abundance of cancer stem cells, modification of cancer cells and their microenvironment, presence of exosomal and non-coding RNA, metabolic reprogramming, and ferroptosis. We aim to focus on the molecular mechanisms of cancer radiotherapy resistance in relation to these aspects and to discuss possible targets to improve treatment outcomes. CONCLUSIONS: Studying the molecular mechanisms responsible for radiotherapy resistance and its interactions with the tumor environment will help improve cancer responses to radiotherapy. Our review provides a foundation to identify and overcome the obstacles to effective radiotherapy.

Direct modulation index: A measure of phase amplitude coupling for neurophysiology data.

Neural communication across different spatial and temporal scales is a topic of great interest in clinical and basic science. Phase-amplitude coupling (PAC) has attracted particular interest due to its functional role in a wide range of cognitive and motor functions. Here, we introduce a novel measure termed the direct modulation index (dMI). Based on the classical modulation index, dMI provides an estimate of PAC that is (1) bound to an absolute interval between 0 and +1, (2) resistant against noise, and (3) reliable even for small amounts of data. To highlight the properties of this newly-proposed measure, we evaluated dMI by comparing it to the classical modulation index, mean vector length, and phase-locking value using simulated data. We ascertained that dMI provides a more accurate estimate of PAC than the existing methods and that is resilient to varying noise levels and signal lengths. As such, dMI permits a reliable investigation of PAC, which may reveal insights crucial to our understanding of functional brain architecture in key contexts such as behaviour and cognition. A Python toolbox that implements dMI and other measures of PAC is freely available at https://github.com/neurophysiological-analysis/FiNN.

Cholesteric Liquid Crystal Polymeric Coatings for Colorful Artificial Muscles and Motile Humidity Sensor Skin Integrated with Magnetic Composites.

Structural colorful cholesterics show impressive susceptibility to external stimulation, leading to applications in electro/mechano-chromic devices. However, out-of-plane actuation of structural colorful actuators based on cholesterics and the integration with other stimulation remains underdeveloped. Herein, colorful actuators and motile humidity sensors are developed using humidity-responsive cholesteric liquid crystal networks (CLCNs) and magnetic composites. The developed colorful actuator can exhibit synergistic out-of-plane shape morphing and color change in response to humidity, with CLCNs as colorful artificial muscles. Through the integration with magnetic control, the motile sensor can be navigated to open and confined spaces with the aid of friction to detect local relative humidity. The integration of multi-stimulation actuation of cholesteric magnetic actuators will expand the research frontier of structural colorful actuators and motile sensors for confined spaces.

Titanium implant alters the effect of zoledronic acid on the behaviour of endothelial cells.

OBJECTIVES: To evaluate the effect of zoledronic acid (ZA) on human umbilical vein endothelial cells (HUVECs) attached to different surfaces. MATERIALS AND METHODS: A total of three groups were evaluated in this study: sandblasting and acid etching (SLA) + HUVECs; mechanically polished (MP) + HUVECs; and plastic cell culture plates + HUVECs. Scanning electron microscopy, energy-dispersive X-ray spectroscopy, surface roughness and water contact angle were tested for titanium surface characterisation. ZA was added at different concentrations (0, 1, 10, 50 and 100 µM). Cell adhesion, proliferation, viability, apoptosis and gene expression were evaluated. RESULTS: Mechanically polished and SLA surfaces showed negative effects on cell adhesion and proliferation and promoted cell apoptosis with 100 µM ZA (p < .05). The highest expression of intercellular adhesion molecule-1 (ICAM-1) and angiopoietin-1 was found on SLA surfaces (p < .01). The lowest expression of platelet-endothelial cell adhesion molecule-1 and ICAM-1 was found on MP surfaces (p < .05). A significant decrease in von Willebrand factor was detected on MP and SLA surfaces (p < .001). CONCLUSIONS: Zoledronic acid has an anti-angiogenic effect on HUVECs attached to titanium implants, while the SLA surface might stimulate HUVECs to express angiogenic and adhesive factor genes despite ZA treatment.

Micro/nano-textured hierarchical titanium topography promotes exosome biogenesis and secretion to improve osseointegration.

BACKGROUND: Micro/nano-textured hierarchical titanium topography is more bioactive and biomimetic than smooth, micro-textured or nano-textured titanium topographies. Bone marrow mesenchymal stem cells (BMSCs) and exosomes derived from BMSCs play important roles in the osseointegration of titanium implants, but the effects and mechanisms of titanium topography on BMSCs-derived exosome secretion are still unclear. This study determined whether the secretion behavior of exosomes derived from BMSCs is differently affected by different titanium topographies both in vitro and in vivo. RESULTS: We found that both micro/nanonet-textured hierarchical titanium topography and micro/nanotube-textured hierarchical titanium topography showed favorable roughness and hydrophilicity. These two micro/nano-textured hierarchical titanium topographies enhanced the spreading areas of BMSCs on the titanium surface with stronger promotion of BMSCs proliferation in vitro. Compared to micro-textured titanium topography, micro/nano-textured hierarchical titanium topography significantly enhanced osseointegration in vivo and promoted BMSCs to synthesize and transport exosomes and then release these exosomes into the extracellular environment both in vitro and in vivo. Moreover, micro/nanonet-textured hierarchical titanium topography promoted exosome secretion by upregulating RAB27B and SMPD3 gene expression and micro/nanotube-textured hierarchical titanium topography promoted exosome secretion due to the strongest enhancement in cell proliferation. CONCLUSIONS: These findings provide evidence that micro/nano-textured hierarchical titanium topography promotes exosome biogenesis and extracellular secretion for enhanced osseointegration. Our findings also highlight that the optimized titanium topography can increase exosome secretion from BMSCs, which may promote osseointegration of titanium implants.

Precise Antibody-Independent m6A Identification via 4SedTTP-Involved and FTO-Assisted Strategy at Single-Nucleotide Resolution.

Innovative detection techniques to achieve precise m6A distribution within mammalian transcriptome can advance our understanding of its biological functions. We specifically introduced the atom-specific replacement of oxygen with progressively larger atoms (sulfur and selenium) at 4-position of deoxythymidine triphosphate to weaken its ability to base pair with m6A, while maintaining A-T* base pair virtually the same as the natural one. 4SedTTP turned out to be an outstanding candidate that endowed m6A with a specific signature of RT truncation, thereby making this "RT-silent" modification detectable with the assistance of m6A demethylase FTO through next-generation sequencing. This antibody-independent, 4SedTTP-involved and FTO-assisted strategy is applicable in m6A identification, even for two closely gathered m6A sites, within an unknown region at single-nucleotide resolution.

Identification of YTH Domain-Containing Proteins as the Readers for N1-Methyladenosine in RNA.

N1-methyladenosine (m1A) is an important post-transcriptional modification in RNA; however, the exact biological role of m1A remains to be determined. By employing a quantitative proteomics method, we identified multiple putative protein readers of m1A in RNA, including several YTH domain family proteins. We showed that YTHDF1-3 and YTHDC1, but not YTHDC2, could bind directly to m1A in RNA. We also found that Trp432 in YTHDF2, a conserved residue in the hydrophobic pocket of the YTH domain that is necessary for its binding to N6-methyladenosine (m6A), is required for its recognition of m1A. An analysis of previously published data revealed transcriptome-wide colocalization of YTH domain-containing proteins and m1A sites in HeLa cells, suggesting that YTH domain-containing proteins can bind to m1A in cells. Together, our results uncovered YTH domain-containing proteins as readers for m1A in RNA and provided new insight into the functions of m1A in RNA biology.

Deficiency of α Calcitonin-gene-related peptide impairs peri-implant angiogenesis and osseointegration via suppressive vasodilative activity.

Blood supply is essential for the bone healing process to obtain successful osseointegration. α Calcitonin gene-related peptide (αCGRP) is osteoanabolic and is the most potent microvascular vasodilator currently known with validated angiogenic effect in vitro. We previously demonstrated that lentiviral αCGRP overexpression vector system could express the gene effectively to enhance titanium implant osseointegration. In this study, we investigated the effect of αCGRP on peri-implant angiogenesis during healing process in vivo. Based on investigation of blood vessel alteration in the peri-implant region of wild-type mice, we found a reduced angiogenesis alongside a decline in bone-implant contact percentage and bone mass in αCGRP -/- mice. Overexpression of αCGRP could partly rescue the impairment. Alterations were also detected in three-dimensional vascular structural parameters and expression of bone and vessel related genes. The results showed αCGRP increased vascular volume fraction and mean vessel size, as well as spatially relocated vessels approximate to the region of bone formation. And angiogenic and osteogenic genes were significantly upregulated in the transfection and αCGRP+/+ group. These results suggested that αCGRP played a synergic role in angiogenesis and osseointegration, partly as a consequence of its vasodilative activity.

Geniposide Attenuates Post-Ischaemic Neurovascular Damage via GluN2A/AKT/ ERK-Dependent Mechanism.

BACKGROUND/AIMS: Calcium-permeable ionotropic NMDAR-mediated hyperactivity is regarded as the critical factor in modulating the development of ischaemic stroke. Recently, there has been increasing interest in preventing post-stroke neuronal death by focusing on intervening in the function of subpopulations of NMDARs and their downstream signalling. Geniposide, an iridoid glycoside, has been found to have cytoprotective functions in various conditions. However, it is still unclear whether and how geniposide affects neuronal insult under experimental stroke. METHODS: We demonstrate that dose-dependent geniposide significantly decreased the infarct volume in tMCAO models. RESULTS: A medium level of geniposide improved anti-apoptotic functions and inhibited BBB leakage/haemorrhage via elevating GluN2A-containing NMDAR expression in tMCAO rats. Importantly, these effects could be eliminated by co-treatment of geniposide with the GluN2A antagonist NVP but not the GluN2B inhibitor ifenprodil. Moreover, geniposide's protection was due to the enhancement of GluN2A-dependent survival signals, including pAKT, pERK and PSD-95. CONCLUSION: The results suggest that geniposide protects neurons against post-ischaemic neurovascular injury through the activation of GluN2A/AKT/ERK pathways. As a very promising natural agent, geniposide may be a future therapeutic for stroke patients.

Beta-adrenergic signaling affect osteoclastogenesis via osteocytic MLO-Y4 cells' RANKL production.

The sympathetic nervous system play a pivotal role in bone remodeling through ß-adrenoceptor (ß-AR). However, it is not well documented whether the ß-adrenoceptor pathway has the potential to influence osteocytes. In this study, cell viability, the expression of ß-AR subtypes, enzymes of catecholamine synthesis or degradation, bone-related gene and protein in osteocytic MLO-Y4 cells were investigated by ß-adrenergic stimulation. Isoproterenol (ISO) promoted RANKL to OPG expression in osteocytes, as well as osteoclasts formation in osteocytes-RAW264.7 cell co-cultures but not RAW264.7 cell monoculture. The ISO-stimulated effect was enhanced in ß1-AR antagonist pretreatment, but was rescued by blocking ß2-AR. The results indicate that ß1-and ß2-AR play reciprocal roles on MLO-Y4 cells in the regulation of osteoclastogenesis, and osteocyte ß-adrenergic signaling might be a new valuable therapy for bone disease.

Association of Topoisomerase II (TOP2A) and Dual-Specificity Phosphatase 6 (DUSP6) Single Nucleotide Polymorphisms with Radiation Treatment Response and Prognosis of Lung Cancer in Han Chinese.

BACKGROUND Mutations of DNA topoisomerase II (TOP2A) are associated with chemotherapy resistance, whereas dual-specificity phosphatase 6 (DUSP6) negatively regulates members of the mitogen-activated protein (MAP) kinase superfamily to control cell proliferation. This study assessed TOP2A and DUSP6 single nucleotide polymorphisms (SNPs) in non-small cell lung cancer (NSCLC) patients for association with chemoradiotherapy responses and prognosis. MATERIAL AND METHODS A total of 140 Chinese patients with histologically confirmed NSCLC were enrolled and subjected to genotyping of TOP2A rs471692 and DUSP6 rs2279574 using Taqman PCR. An independent sample t test was used to analyze differences in tumor regression after radiotherapy versus SNP risk factors. Kaplan-Meier curves analyzed overall survival, followed by the log-rank test and Cox proportional hazard models. RESULTS There were no significant associations of TOP2A rs471692 and DUSP6 rs2279574 polymorphisms or clinicopathological variables with response to chemoradiotherapy (p>0.05). Comparing overall survival of 87 patients with stage I-III NSCLC treated with radiotherapy or chemoradiotherapy to clinicopathological variables, the data showed that tumor regression, weight loss, clinical stage, and cigarette smoking were independent prognostic predictors (p=0.009, 0.043, 0.004, and 0.025, respectively). Tumor regression rate >0.34 was associated with patent survival versus tumor regression rate ≤0.34 (p=0.007). CONCLUSIONS TOP2A rs471692 and DUSP6 rs2279574 SNPs were not associated with chemoradiotherapy response, whereas tumor regression, weight loss, clinical stage, and cigarette smoking were independent prognostic predictors for these Chinese patients with NSCLC.

Highly Selective Detection of 5-Methylcytosine in Genomic DNA Based on Asymmetric PCR and Specific DNA Damaging Reagents.

DNA methylation is a significant epigenetic modification of the genome that is involved in regulating many cellular processes. An increasing number of human diseases have been discovered to be associated with aberrant DNA methylation, and aberrant DNA methylation has been deemed to be a potential biomarker for diseases such as cancers. A safe, nontoxic, and sensitive method for accurate detection of 5-methylcytosine in genomic DNA is extremely useful for early diagnosis and therapy of cancers. In this paper, we established a novel system to detect 5-methylcytosine, which is based on bisulfite treatment, asymmetric PCR, and specific DNA damaging reagents. Our method could be used for identifying the loci of 5mC in genomic DNA and detecting the DNA methylation levels in tissues as well.

GlyT1 Inhibitor NFPS Exerts Neuroprotection via GlyR Alpha1 Subunit in the Rat Model of Transient Focal Cerebral Ischaemia and Reperfusion.

BACKGROUND/AIMS: Glycine is a strychnine-sensitive inhibitory neurotransmitter in the central nervous system (CNS), especially in the spinal cord, brainstem, and retina. The objective of the present study was to investigate the potential neuroprotective effects of GlyT1 inhibitor N [3-(4'-fluorophenyl)-3-(4'-phenylphenoxy) propyl] sarcosine (NFPS) in the rat model of experimental stroke. METHODS: In vivo ischaemia was induced by transient middle cerebral artery occlusion (tMCAO). The methods of Western Blotting, Nissl Staining and Morris water maze methods were applied to analyze the anti-ischaemia mechanism. RESULTS: The results showed that high dose of NFPS (H-NFPS) significantly reduced infarct volume, neuronal injury and the expression of cleaved caspase-3, enhanced Bcl-2/Bax, and improved spatial learning deficits which were administered three hours after transient middle cerebral artery occlusion (tMCAO) induction in rats, while, low dose of NFPS (L-NFPS) exacerbated the injury of ischaemia. These findings suggested that low and high dose of NFPS produced opposite effects. Importantly, it was demonstrated that H-NFPS-dependent neuronal protection was inverted by salicylate (Sal), a specific GlyR x0251;1 antagonist. Such effects could probably be attributed to the enhanced glycine level in both synaptic and extrasynaptic clefts and the subsequently altered extrasynaptic GlyRs and their subtypes. CONCLUSIONS: These data imply that GlyT1 inhibitor NFPS may be a novel target for clinical treatment of transient focal cerebral ischaemia and reperfusion which are associated with altered GlyR alpha 1 subunits.

Dual Specificity Phosphatase 6 (DUSP6) Polymorphism Predicts Prognosis of Inoperable Non-Small Cell Lung Cancer after Chemoradiotherapy.

BACKGROUND: Dual-specificity phosphatase 6 (DUSP6) inactivates different target kinases to regulate cell proliferation and differentiation. Altered DUSP6 expressions or gene polymorphisms are associated with human cancer development including non-small cell lung cancer (NSCLC). DNA topoisomerase II alpha (TOP2A) regulates chromosome condensation and chromatid separation, and altered TOP2A expressions are associated with drug resistance development. This study assessed DUSP6 and TOP2A single nucleotide polymorphisms (SNPs) associated with NSCLC patient survival. METHODS: This study included 152 surgically resected NSCLC patients and 277 chemoradiotherapy treated inoperable cases. DNA samples from each patient were genotyped for DUSP6 and TOP2A SNPs. Kaplan-Meier survival analysis, log-rank test, and Cox proportional hazard model were used to evaluate the association between these variants and NSCLC overall survival. RESULTS: DUSP6 rs2279574 A/A genotype was associated with significantly poor inoperable NSCLC patient overall survival (A/A vs. C/C, adjusted HR = 1.549, 95% CI = 1.019-2.355). Stratification analysis against clinical stage, histology, weight loss, and ECOG performance status revealed that the DUSP6 rs2279574 A/A variant homozygous genotype is associated with a decrease in survival of stage IV NSCLC patients compared to those with the C/C genotype (log-rank, p = 0.003). No association was found among histology, weight loss, and ECOG performance status. Moreover, there was no association of TOP2A SNPs between clinicopathological and survival data. CONCLUSIONS: Data obtained from the current study demonstrated that functional DUSP6 rs2279574 polymorphism was able to predict inoperable NSCLC patient survival after chemoradiotherapy.

Fluorescein Derivatives as Bifunctional Molecules for the Simultaneous Inhibiting and Labeling of FTO Protein.

The FTO protein is unequivocally reported to play a critical role in human obesity and in the regulation of cellular levels of m(6)A modification, which makes FTO a significant and worthy subject of study. Here, we identified that fluorescein derivatives can selectively inhibit FTO demethylation, and the mechanisms behind these activities were elucidated after we determined the X-ray crystal structures of FTO/fluorescein and FTO/5-aminofluorescein. Furthermore, these inhibitors can also be applied to the direct labeling and enrichment of FTO protein combined with photoaffinity labeling assay.

Evaluation of the efficacy of keratinized mucosa augmentation techniques around dental implants: a systematic review.

STATEMENT OF PROBLEM: The absence of periimplant keratinized mucosa is considered risky in patients with a predisposition to periodontitis or recession. Although various soft tissue augmentation techniques exist, dentists are seeking for more efficient approaches to augment periimplant keratinized mucosa. PURPOSE: The purpose of this systematic review was to evaluate the efficacy of the various techniques and biomaterials adopted in periimplant keratinized mucosa augmentation and whether one technique or biomaterial is superior. MATERIAL AND METHODS: A search in Medline-PubMed and the Cochrane Central Register of controlled trials was conducted. Randomized clinical trials, prospective cohort studies, clinical control studies, and case series from January 1, 1980, to December 31, 2013, with a follow-up of at least 6 months reporting changes on keratinized mucosa width were included. Several journals were hand-searched for related articles. The bibliographies of all publications selected for inclusion were also scanned. RESULTS: The screening of titles and abstracts resulted in 60 relevant publications. Six of them were finally included. Free gingival graft, connective tissue graft, acellular dermal matrix, and collagen matrix were used for keratinized mucosa augmentation. Because of heterogeneity of the studies, only descriptive analysis was performed. Improvements in keratinized mucosa width were reported in all studies. CONCLUSIONS: A definitive conclusion could not be achieved owing to the lack of well-designed studies and appropriate methods of studying soft tissue. The establishment of universal surgical guidelines and measurement systems is imperative in the future.