Temperature and Twist Sensor Based on the Sagnac Interferometer with Long-Period Grating in Polarization-Maintaining Fiber.

We utilized a CO2 laser to carve long-period fiber gratings (LPFGs) on polarization-maintaining fibers (PMFs) along the fast and slow axes. Based on the spectra of LPFGs written along two different directions, we found that when LPFG was written along the fast axis, the spectrum had lower insertion loss and fewer side lobes. We investigated the temperature and twist characteristics of the embedded structure of the LPFG and Sagnac loop and ultimately obtained a temperature sensitivity of -0.295 nm/°C and a twist sensitivity of 0.87 nm/(rad/m) for the LPFG. Compared to the single LPFG, the embedded structure of the LPFG and Sagnac loop demonstrates a significant improvement in temperature and twist sensitivities. Additionally, it also possesses the capability to discern the direction of the twist. The embedded structure displays numerous advantages, including easy fabrication, low cost, good robustness, a wide range, and high sensitivity. These features make it highly suitable for applications in structural health monitoring and other related fields.

High-Sensitivity Temperature Sensor Based on Fiber Fabry-Pérot Interferometer with UV Glue-Filled Hollow Capillary Fiber.

Optical fiber Fabry-Pérot (FP) interferometer sensors have long been the focus of researchers in sensing applications because of their simple light path, low cost, compact size and convenient manufacturing methods. A miniature and highly sensitive optic fiber temperature sensor using an ultraviolet glue-filled FP cavity in a hollow capillary fiber is proposed. The sensor is fabricated by fusion splicing a single-mode fiber with a hollow capillary fiber, which is filled with ultraviolet glue to form a FP cavity. The sensor has a good linear response in the temperature testing and high-temperature sensitivity, which can be increased with the length of the FP cavity. The experimental results show that the temperature sensitivity reaches 1.174 nm/°C with a high linear response in the range of 30-60 °C. In addition, this sensor is insensitive to pressure and can be highly suitable for real-time water temperature monitoring for ocean research. The proposed ultraviolet glue-filled structure has the advantages of easy fabrication, high-temperature sensitivity, low cost and an arbitrary length of capillary, which has broad application prospects for marine survey technology, biological diagnostics and environmental monitoring.

Targeting the Limbic System: Insights into Its Involvement in Tinnitus.

Tinnitus is originally derived from the Latin verb tinnire, which means "to ring". Tinnitus, a complex disorder, is a result of sentient cognizance of a sound in the absence of an external auditory stimulus. It is reported in children, adults, and older populations. Patients suffering from tinnitus often present with hearing loss, anxiety, depression, and sleep disruption in addition to a hissing and ringing in the ear. Surgical interventions and many other forms of treatment have been only partially effective due to heterogeneity in tinnitus patients and a lack of understanding of the mechanisms of tinnitus. Although researchers across the globe have made significant progress in understanding the underlying mechanisms of tinnitus over the past few decades, tinnitus is still deemed to be a scientific enigma. This review summarises the role of the limbic system in tinnitus development and provides insight into the development of potential target-specific tinnitus therapies.

Optical Fiber Probe Microcantilever Sensor Based on Fabry-Perot Interferometer.

Optical fiber Fabry-Perot sensors have long been the focus of researchers in sensing applications because of their unique advantages, including highly effective, simple light path, low cost, compact size, and easy fabrication. Microcantilever-based devices have been extensively explored in chemical and biological fields while the interrogation methods are still a challenge. The optical fiber probe microcantilever sensor is constructed with a microcantilever beam on an optical fiber, which opens the door for highly sensitive, as well as convenient readout. In this review, we summarize a wide variety of optical fiber probe microcantilever sensors based on Fabry-Perot interferometer. The operation principle of the optical fiber probe microcantilever sensor is introduced. The fabrication methods, materials, and sensing applications of an optical fiber probe microcantilever sensor with different structures are discussed in detail. The performances of different kinds of fiber probe microcantilever sensors are compared. We also prospect the possible development direction of optical fiber microcantilever sensors.

Research on High Sensitivity Oil Debris Detection Sensor Using High Magnetic Permeability Material and Coil Mutual Inductance.

Metallic contaminants (solid) are generated by friction pair, causing wear of equipment by enters the lubricating system. This poses a great potential threat to the normal operation of such machines. The timely analysis and detection of debris can lead to the avoidance of mechanical failures. Abnormal wear in machinery may produce debris exceeding 10 µm. The traditional inductance detection method has low sensitivity and cannot meet the actual detection requirements. To boost the sensitivity of the inductance sensor, the mutual inductance of coils and the strong magnetic conductivity of permalloy was utilized to design a high sensitivity inductance sensor for the detection of debris in lubricating oil. This design was able to detect 10-15 µm iron particles and 65-70 µm copper particles in the oil. The experimental results illustrate that low-frequency excitation is the best for detecting ferromagnetic particles, while high-frequency excitation has the best effect for detecting non-ferromagnetic particles. This paper demonstrates the significant advantages of coil mutual inductance, and strong magnetic conductivity of permalloy in improving the detection sensitivity of oil debris sensors. This will provide technical support for wear detection in mechanical equipment and fault diagnosis.

PHLDA3 promotes lung adenocarcinoma cell proliferation and invasion via activation of the Wnt signaling pathway.

The PHLDA3 gene encodes a small 127 amino acid protein with a pleckstrin homology (PH)-only domain. The expression and significance of PHLDA3 in lung cancer remain unclear. Here, we investigated the role of PHLDA3 in tumor proliferation and invasion in lung adenocarcinoma. Immunohistochemistry and immunoblotting analyses were used to assess PHLDA3 expression in lung cancer tissues, and its correlation with clinicopathological factors in lung cancer. Plasmids encoding PHLDA3 and small interfering RNA against PHLDA3 were used to regulate the expression of PHLDA3 in lung cancer cells. Furthermore, the effects of PHLDA3 on lung cancer cell proliferation and invasion were investigated using the MTS, colony formation, Matrigel invasion, and wound healing assays. Co-immunoprecipitation analysis and inhibitors of both the Wnt signaling pathway and GSK3ß were used to explore the regulatory mechanisms underlying the role of PHLDA3 in lung cancer cells. PHLDA3 was found to be overexpressed in lung cancer tissues, and its expression was correlated with poor outcomes in lung adenocarcinoma patients. PHLDA3 expression promoted the proliferation, invasion, and migration of lung cancer cells. Overexpression of PHLDA3 activated the Wnt signaling pathway and facilitated epithelial-mesenchymal transition. Inhibition of Wnt signaling pathway activity, using XAV-939, reversed the effects of PHLDA3 overexpression in lung cancer cells; moreover, PHLDA3 could bind to GSK3ß. Inhibition of GSK3ß activity, using CHIR-99021, restored the proliferative and invasive abilities of PHLDA3 knockdown cells. Our findings demonstrate that PHLDA3 is highly expressed in lung adenocarcinomas and is correlated with poor outcomes. Furthermore, it promotes the proliferation and invasion of lung cancer cells by activating the Wnt signaling pathway.

Mechanisms and pharmacokinetic/pharmacodynamic profiles underlying the low nephrotoxicity and ototoxicity of etimicin.

Etimicin (ETM), a fourth-generation aminoglycosides (AGs), is now widely clinically used in China due to its high efficacy and low toxicity. However, the mechanisms underlying its low nephrotoxicity and ototoxicity remain unclear. In the present study we compared the antibacterial and toxicity profiles of etimicin, gentamicin (GM, a second-generation AG), and amikacin (AMK, a third-generation AG), and investigated their pharmacokinetic properties in the toxicity target organs (kidney and inner ear) and subcellular compartments. We first demonstrated that ETM exhibited superior antibacterial activities against clinical isolates to GM and AMK, and it exerted minimal nephrotoxicity and ototoxicity in rats following multi-dose administration. Then, we conducted pharmacokinetic studies in rats, showed that the three AGs accumulated in the kidney and inner ear with ETM being distributed to a lesser degree in the two toxicity target organs as compared with GM and AMK high-dose groups. Furthermore, we conducted in vitro experiments in NRK-52E rat renal tubular epithelial cells and HEI-OC1 cochlear hair cells, and revealed that all the three AGs were distributed predominantly in the mitochondria with ETM showing minimal accumulation; they not only directly inhibited the activity of mitochondrial complexes IV and V but also inhibited mitochondrial function and its related PGC-1α-NRF1-TFAM pathway; ETM caused minimal damage to the mitochondrial complex and mitochondrial biogenesis. Our results demonstrate that the minimal otonephrotoxicity of ETM results from its lesser accumulation in mitochondria of target cells and subsequently lesser inhibition of mitochondrial function. These results provide a new strategy for discovering novel AGs with high efficacy and low toxicity.

Cannabinoid drugs: will they relieve or exacerbate tinnitus?

PURPOSE OF REVIEW: Recent enthusiasm for cannabinoid drugs for the treatment of chronic pain and some forms of epilepsy, raises the question of whether they could be useful for other disorders associated with abnormal neuronal activity in the brain, such as subjective tinnitus. Indeed, there is evidence to indicate that some tinnitus sufferers self-medicate using Cannabis. The aim of this review is to critically evaluate the available evidence relating to the effects of cannabinoids on tinnitus. RECENT FINDINGS: Despite the fact that cannabinoids have been shown to decrease neuronal hyperactivity in many parts of the brain, the current evidence suggests that in auditory brain regions such as the dorsal cochlear nucleus, they have the potential to facilitate neuronal hyperactivity and exacerbate tinnitus. All of the available experimental evidence from animal studies suggests that cannabinoid CB1 receptor agonists will either have no effect on tinnitus or will worsen it. SUMMARY: In our opinion, the use of the available cannabinoid drugs to alleviate tinnitus, based on their alleged efficacy for neuropathic pain conditions and some forms of epilepsy, is premature and not supported by the available evidence.

Role of identified RNA N6-methyladenosine methylation in liver.

N6-Methyladenosine (m6A) is the most abundant and important internal modification site of RNA methylation in viruses and eukaryotic. m6A RNA methylation plays key roles in the regulation of post-transcriptional gene expression, including messenger RNA (mRNA), microRNA (miRNA) and long noncoding RNA (lncRNA). And m6A methylation regulates the various aspects of RNA metabolism, including structure, maturation, stability, splicing, export, translation and decay. Liver is a vital metabolic and digestive organ in the pathophysiological processes. Recent studies suggested that m6A RNA modification highly regulates hepatic function and development of liver diseases. Here, we aim to summarize the biological and clinical significance of m6A modification in hepatic growth and hepatic disease including viral hepatitis, non-alcoholic fatty liver disease (NAFLD), and liver cancer.

The modulation of hippocampal theta rhythm by the vestibular system.

The vestibular system is a sensory system that has evolved over millions of years to detect acceleration of the head, both rotational and translational, in three dimensions. One of its most important functions is to stabilize gaze during unexpected head movement; however, it is also important in the control of posture and autonomic reflexes. Theta rhythm is a 3- to 12-Hz oscillating EEG signal that is intimately linked to self-motion and is also known to be important in learning and memory. Many studies over the last two decades have shown that selective activation of the vestibular system, using either natural rotational or translational stimulation, or electrical stimulation of the peripheral vestibular system, can induce and modulate theta activity. Furthermore, inactivation of the vestibular system has been shown to significantly reduce theta in freely moving animals, which may be linked to its impairment of place cell function as well as spatial learning and memory. The pathways through which vestibular information modulate theta rhythm remain debatable. However, vestibular responses have been found in the pedunculopontine tegmental nucleus (PPTg) and activation of the vestibular system causes an increase in acetylcholine release into the hippocampus, probably from the medial septum. Therefore, a pathway from the vestibular nucleus complex and/or cerebellum to the PPTg, supramammillary nucleus, posterior hypothalamic nucleus, and septum to the hippocampus is likely. The modulation of theta by the vestibular system may have implications for vestibular effects on cognitive function and the contribution of vestibular impairment to the risk of dementia.

Odd-skipped related 1 inhibits lung cancer proliferation and invasion by reducing Wnt signaling through the suppression of SOX9 and ß-catenin.

The odd-skipped related 1 (OSR1) gene encodes a zinc-finger transcription factor. The expression and significance of OSR1 in human tumors remains unclear. We found that OSR1 was downregulated in lung cancers, and its expression was correlated with poor differentiation. Overexpression of OSR1 by OSR1 gene transfection into H1299 cells (H1299-OSR1) inhibited the proliferation and invasion of lung cancer cells. Knockdown of OSR1 with small interfering (si)RNA against OSR1 in A549 cells (A549-siOSR1) enhanced the proliferation and invasion of lung cancer cells. Western blot analysis showed that the expression level of GSK3ß increased, while that of p-GSK3ß, nuclear ß-catenin, cyclin D1, c-Myc and matrix metallopeptidase 7 significantly decreased in the H1299-OSR1 cells, and this pattern was reversed in the A549-siOSR1 cells compared to that in the control cells. Furthermore, upregulation of sex-determining region Y-box 9 (SOX9) by SOX9 gene transfection increased the expression of ß-catenin, which was inhibited by OSR1. The mRNA and protein expression levels of SOX9 and ß-catenin were reduced in H1299-OSR1 cells and increased in A549-siOSR1 cells. In conclusion, the expression of OSR1 was more reduced in lung cancer tissues than in normal lung tissues, and was correlated with poor differentiation. OSR1 downregulated the activity of the Wnt signaling pathway by suppressing the expression of SOX9 and ß-catenin.

Vestibular-related eye movements in the rat following selective electrical stimulation of the vestibular sensors.

Rats are the most commonly used species in the neurosciences; however, little is known about the effects of selective electrical stimulation of individual vestibular sensors, on their eye movements. This limits their use to study the effects of vestibular stimulation on the brain, and their use in further exploring novel technologies such as artificial vestibular implants. We describe the effects of electrical stimulation of each vestibular sensor on vestibular-related eye movement in rats and compared the results to other species. We demonstrated that each sensor is responsible for specific bilateral eye movements. We found that the eye movements in rats differed from other species. Although the results were similar when stimulating the horizontal canal ampulla, differences appeared when stimulating the vertical canal sensors. During utricular stimulation, the ipsilateral eye moved dorsally in most cases, while the contralateral eye usually moved either caudally, or in extorsion. Saccular stimulation usually moved the ipsilateral eye dorsally or ventrally, while the contralateral eye usually moved ventrally or caudally. This study provides the first data on the application of selective electrical vestibular stimulation in the rat to the study of vestibular-related eye movements.

Photocatalytic Hydrogen-Evolution Cross-Couplings: Benzene C-H Amination and Hydroxylation.

We present a blueprint for aromatic C-H functionalization via a combination of photocatalysis and cobalt catalysis and describe the utility of this strategy for benzene amination and hydroxylation. Without any sacrificial oxidant, we could use the dual catalyst system to produce aniline directly from benzene and ammonia, and phenol from benzene and water, both with evolution of hydrogen gas under unusually mild conditions in excellent yields and selectivities.

Hippocampal and striatal M1 -muscarinic acetylcholine receptors are down-regulated following bilateral vestibular loss in rats.

Permanent vestibular loss has detrimental effects on the hippocampus, resulting in a disruption to spatial learning and memory, hippocampal theta rhythm and place cell field spatial coherence. Little is known about the vestibular system-related hippocampal cholinergic transmission. Since the pharmacological blockade of muscarinic acetylcholine (ACh) receptors within the hippocampus produces deficits in learning and memory, we hypothesized that ACh receptors may at least partly support the integration of vestibular input. Consequently, we examined the expression of M1 muscarinic ACh receptors in the hippocampus at 7 and 30 days following bilateral vestibular lesions (BVL) in rats using autoradiography. Animals were divided into sham (n = 12) and BVL (n = 11) groups. BVL animals received intratympanic injections of sodium arsanilate (30 mg/0.1 ml) under isoflurane anesthesia and sham animals received the same volume of saline. Analysis of the brain tissue revealed a significant reduction in the number of M1 receptors throughout the hippocampus and striatum at 30 days (P ≤ 0.0001), but not at 7 days following BVL. This suggests that the changes in learning and memory seen following vestibular damage may be in part due to the loss of M1 muscarinic receptors in the hippocampus and striatum. © 2016 Wiley Periodicals, Inc.

Basal dendritic length is reduced in the rat hippocampus following bilateral vestibular deafferentation.

Some previous studies in humans have shown that bilateral loss of vestibular function is associated with a significant bilateral atrophy of the hippocampus, which correlated with the patients' spatial memory deficits. By contrast, studies in rats have failed to detect any changes in hippocampal volume following bilateral vestibular loss. Therefore, in this study we investigated whether bilateral vestibular deafferentation (BVD) might result in more subtle morphological changes in the rat hippocampus, involving alterations in dendritic intersections, using Golgi staining and Sholl analysis. We found that at 1month following BVD, there was a significant decrease in basal (P⩽0.0001) but not apical dendritic intersections in the CA1 region of the hippocampus compared to sham-operated animals and anaesthetic controls. However, dendritic branching was not significantly affected. These results suggest that the rat hippocampus does undergo subtle morphological changes following bilateral vestibular loss, and that they may be in the form of alterations in dendritic structure.

Activation of CH Bonds through Oxidant-Free Photoredox Catalysis: Cross-Coupling Hydrogen-Evolution Transformation of Isochromans and ß-Keto Esters.

The direct and controlled activation of a C(sp(3) )H bond adjacent to an O atom is of particular synthetic value for the conventional derivatization of ethers or alcohols. In general, stoichiometric amounts of an oxidant are required to remove an electron and a hydrogen atom of the ether for subsequent transformations. Herein, we demonstrate that the activation of a CH bond next to an O atom could be achieved under oxidant-free conditions through photoredox-neutral catalysis. By using a commercial dyad photosensitizer (Acr(+) -Mes ClO4 (-) , 9-mesityl-10-methylacridinium perchlorate) and an easily available cobaloxime complex (Co(dmgBF2 )2 ⋅2 MeCN, dmg=dimethylglyoxime), the nucleophilic addition of ß-keto esters to oxonium species, which is rarely observed in photocatalysis, leads to the corresponding coupling products and H2 in moderate to good yields under visible-light irradiation. Mechanistic studies suggest that both isochroman and the cobaloxime complex quench the electron-transfer state of this dyad photosensitizer and that benzylic CH bond cleavage is probably the rate-determining step of this cross-coupling hydrogen-evolution transformation.

Galvanic vestibular stimulation impairs cell proliferation and neurogenesis in the rat hippocampus but not spatial memory.

Galvanic vestibular stimulation (GVS) is a method of activating the peripheral vestibular system using direct current that is widely employed in clinical neurological testing. Since movement is recognized to stimulate hippocampal neurogenesis and movement is impossible without activation of the vestibular system, we speculated that activating the vestibular system in rats while minimizing movement, by delivering GVS under anesthesia, would affect hippocampal cell proliferation and neurogenesis, and spatial memory. Compared with the sham control group, the number of cells incorporating the DNA replication marker, bromodeoxyuridine (BrdU), was significantly reduced in the bilateral hippocampi in both the cathode left-anode right and cathode right-anode left stimulation groups (P ≤ 0.0001). The majority of the BrdU(+ve) cells co-expressed Ki-67, a marker for the S phase of the cell cycle, suggesting that these BrdU(+ve) cells were still in the cell cycle; however, there was no significant difference in the degree of co-labeling between the two stimulation groups. Single labeling for doublecortin (DCX), a marker of immature neurons, showed that while there was no significant difference between the different groups in the number of DCX(+ve) cells in the right dentate gryus, in the left dentate gyrus there was a significant decrease in the cathode left-anode right group compared with the sham controls (P ≤ 0.03). Nonetheless, when animals were tested in place recognition, object exploration and Morris water maze tasks, there were no significant differences between the GVS groups and the sham controls. These results suggest that GVS can have striking effects on cell proliferation and possibly neurogenesis in the hippocampus, without affecting spatial memory.

Mandarin fish caveolin 1 interaction with major capsid protein of infectious spleen and kidney necrosis virus and its role in early stages of infection.

Infectious spleen and kidney necrosis virus (ISKNV) is the type species of the genus Megalocytivirus from the family Iridoviridae. ISKNV is one of the major agents that cause mortality and economic losses to the freshwater fish culture industry in Asian countries, particularly for mandarin fish (Siniperca chuatsi). In the present study, we report that the interaction of mandarin fish caveolin 1 (mCav-1) with the ISKNV major capsid protein (MCP) was detected by using a virus overlay assay and confirmed by pulldown assay and coimmunoprecipitation. This interaction was independent of the classic caveolin 1 scaffolding domain (CSD), which is responsible for interacting with several signaling proteins and receptors. Confocal immunofluorescence microscopy showed that ISKNV MCP colocalized with mCav-1 in the perinuclear region of virus-infected mandarin fish fry (MFF-1) cells, which appeared as soon as 4 h postinfection. Subcellular fractionation analysis showed that ISKNV MCP was associated with caveolae in the early stages of viral infection. RNA interference silencing of mCav-1 did not change virus-cell binding but efficiently inhibited the entry of virions into the cell. Taken together, these results suggested that mCav-1 plays an important role in the early stages of ISKNV infection.

Time-dependent effects of acoustic trauma and tinnitus on extracellular levels of amino acids in the inferior colliculus of rats.

Chronic tinnitus is a debilitating condition with very few management options. Acoustic trauma that causes tinnitus has been shown to induce neuronal hyperactivity in multiple brain areas in the auditory pathway, including the inferior colliculus. This neuronal hyperactivity could be attributed to an imbalance between excitatory and inhibitory neurotransmission. However, it is not clear how the levels of neurotransmitters, especially neurotransmitters in the extracellular space, change over time following acoustic trauma and the development of tinnitus. In the present study, a range of amino acids were measured in the inferior colliculus of rats during acoustic trauma as well as at 1 week and 5 months post-trauma using in vivo microdialysis and high-performance liquid chromatography. Amino acid levels in response to sound stimulation were also measured at 1 week and 5 months post-trauma. It was found that unilateral exposure to a 16 kHz pure tone at 115 dB SPL for 1 h caused immediate hearing loss in all the animals and chronic tinnitus in 58 % of the animals. Comparing to the sham condition, extracellular levels of GABA were significantly increased at both the acute and 1 week time points after acoustic trauma. However, there was no significant difference in any of the amino acid levels measured between sham, tinnitus positive and tinnitus negative animals at 5 months post-trauma. There was also no clear pattern in the relationship between neurochemical changes and sound frequency/acoustic trauma/tinnitus status, which might be due to the relatively poorer temporal resolution of the microdialysis compared to electrophysiological responses.