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Surface plasmon resonance (SPR) sensors are based on photon-excited surface charge density oscillations confined at metal-dielectric interfaces, which makes them highly sensitive to biological or chemical molecular bindings to functional metallic surfaces. Metal nanostructures further concentrate surface plasmons into a smaller area than the diffraction limit, thus strengthening photon-sample interactions. However, plasmonic sensors based on intensity detection provide limited resolution with long acquisition time owing to their high vulnerability to environmental and instrumental noises. Here, we demonstrate fast and precise detection of noble gas dynamics at single molecular resolution via frequency-comb-referenced plasmonic phase spectroscopy. The photon-sample interaction was enhanced by a factor of 3,852 than the physical sample thickness owing to plasmon resonance and thermophoresis-assisted optical confinement effects. By utilizing a sharp plasmonic phase slope and a high heterodyne information carrier, a small atomic-density modulation was clearly resolved at 5 Hz with a resolution of 0.06 Ar atoms per nano-hole (in 10–11 RIU) in Allan deviation at 0.2 s; a faster motion up to 200 Hz was clearly resolved. This fast and precise sensing technique can enable the in-depth analysis of fast fluid dynamics with the utmost resolution for a better understanding of biomedical, chemical, and physical events and interactions. [ABSTRACT FROM AUTHOR]

Background: Myasthenia gravis (MG) can affect cardiac muscles with variable presentations. Myocarditis is a rare but potentially serious cardiac manifestation of MG. Although thymomas and anti-titin antibodies have been suggested as risk factors for myocarditis in patients with MG, their independent influence on myocarditis has rarely been assessed. Methods: A retrospective chart review was conducted on 247 patients diagnosed with MG who were tested for anti-titin antibodies. Myocarditis was diagnosed on the basis of the European Society of Cardiology 2013 Task Force criteria for clinically suspected myocarditis. Patients were classified into myocarditis-positive and myocarditis-negative groups. Multivariate analysis was performed to analyze the risk factors for myocarditis. Results: Of the 247 patients, 25 (10.1%) were myocarditis-positive and 222 (89.9%) were myocarditis-negative. Anti-titin antibody positivity was higher in the myocarditis-positive group than in the myocarditis-negative group (68.0% vs. 28.4%, p < 0.001). A history of MG crisis was more frequent in the myocarditis-positive group than in the myocarditis-negative group (64.0% vs. 10.4%, p < 0.001). The presence of anti-titin antibodies (odds ratio [OR] 7.906; confidence interval [CI] 2.460–25.401) and MG crisis (OR 24.807; CI 7.476–82.311) was significantly associated with myocarditis. The Cox regression model showed that the anti-titin antibody levels (hazard ratio [HR] 3.639; 95% CI 1.557–8.505) and MG crisis (HR 6.137; 95% CI 2.639–14.272) were significant risk factors for the development of myocarditis. Conclusion: The presence of anti-titin antibody was associated with myocarditis in patients with MG, whereas thymoma was not. Although rare, early suspicion of myocarditis could be required, especially in patients with MG having anti-titin antibodies. [ABSTRACT FROM AUTHOR]

To assess whether older age and presence of comorbidities were associated with a delayed diagnosis of Guillain–Barré syndrome (GBS). The medical records of 140 patients diagnosed with GBS at Severance Hospital from March 2011 to December 2020 were retrospectively reviewed. Comorbidity profiles were assessed using the Charlson comorbidity index (CCI). The age-adjusted CCI (ACCI) score was calculated, which further incorporated the effect of age. Patients were classified into the early diagnosis group (diagnosis duration ≤ 14 days) and late diagnosis group (diagnosis duration > 14 days). Clinical features and comorbidity profiles were compared between the two groups. The cumulative incidence of diagnosis was compared between the low and high ACCI groups. Age was significantly higher in the late diagnosis group (61.8 ± 15.0 years) than in the early diagnosis group (49.1 ± 18.4, p = 0.001). The CCI score was higher in the late diagnosis group (≥ 3 in 26.1%) than in the early diagnosis group (≥ 3 in 5.1%, p = 0.01). The ACCI score demonstrated a positive correlation with the diagnosis duration (β = 1.636, p < 0.001), indicating that the diagnosis was delayed in patients with a higher ACCI score. The duration from onset to diagnosis was longer in the high ACCI group than in the low ACCI group (log-rank test, p < 0.001). The diagnosis duration was significantly longer, especially in patients with malignancy and cardiovascular diseases. Delayed diagnosis of GBS is associated with older age and multiple comorbidities. Diagnostic delay was significant in patients with malignancies and cardiovascular diseases. Early suspicion of GBS is required in these patients. [ABSTRACT FROM AUTHOR]

Oral microbiota can alter cancer susceptibility and progression by modulating metabolism and inflammation. We assessed the association between the oral microbiome and lymph node (LN) metastasis in oral squamous cell carcinoma (OSCC). We collected a total of 54 saliva samples from patients with OSCC before surgery. LN metastasis was assessed based on postoperative pathological examination. We used QIIME2, linear discriminant analysis effect size (LEfSe), and PICRUSt2 methods to analyze microbial dysbiosis. A random forest classifier was used to assess whether the oral microbiome could predict LN metastasis. Among the 54 OSCC samples, 20 had LN metastasis, and 34 had no evidence of metastasis. There was a significant difference in β-diversity between the metastasis and no metastasis groups. Through LEfSe analysis, the metastasis group was enriched in the genera Prevotella, Stomatobaculum, Bifidobacterium, Peptostreptococcaceae, Shuttleworthia and Finegoldia. Pathways related to signal peptidase II were predominant in the no metastasis group. The RF model showed a modestly high accuracy for predicting metastasis. Differences in microbial community composition and functions were observed in the oral microbiome of patients with OSCC with and without LN metastasis. However, the finding that specific taxa may be associated with LN metastasis should be verified in a further prospective study. [ABSTRACT FROM AUTHOR]

We present an integrated scheme of 3-D surface profile measurements made at multiple sites concurrently by employing only a single fiber femtosecond laser as the common light source of low coherence scanning interferometry. This versatile use of an ultrashort mode-locked laser is enabled by linear scanning control of the pulse repetition rate on the source site, while diverse forms of unequal-path, non-symmetric measurements are taken with nanometer precision for different targets simply by delivering fr-scanned pulses through a fiber network. This proposed scheme has no restriction on the number of interferometer sites being integrated concurrently, allowing more diverse industrial applications of ultrashort lasers despite increased system cost and complexity. [ABSTRACT FROM AUTHOR]

Whether thymectomy is beneficial in elderly patients with myasthenia gravis (MG) is unclear. Thus, we assessed whether conducting thymectomy in MG patients aged ≥ 50 years is beneficial. This retrospective cohort study included patients with MG between 1990 and 2018. Thymectomy and control cohorts were selected from among the population of MG patients with an age at onset of ≥ 45 years and elevated concentrations of acetylcholine-receptor antibodies. Patients with evidence of thymic malignancy were excluded. Of these patients, those who underwent thymectomy at the age of ≥ 50 years were designated as the thymectomy group and those who received only medical treatment were designated as the medical treatment group. We compared the Myasthenia Gravis Foundation of America post-intervention status between the thymectomy and medical treatment groups. Landmark analysis was conducted with the landmark set at 24 months. A total of 34 and 105 patients were classified into the thymectomy and medical treatment groups, respectively. Before landmark analysis, the thymectomy group had a higher cumulative incidence of pharmacologic remission (p = 0.009) and complete stable remission (p = 0.022) than the medical treatment group. After landmark analysis, the thymectomy group had a 2.22-fold (95% confidence interval 1.01-4.80) increased chance of achieving pharmacologic remission compared to the medical treatment group after adjustment for age, sex, and disease severity. No significant difference was observed in the rate of relapse after pharmacological remission between the thymectomy (16.7%) and medical treatment groups (21.4%). In conclusion, thymectomy may have a beneficial effect in elderly patients with non-thymomatous generalized MG. [ABSTRACT FROM AUTHOR]

It has been reported that the innate immune response plays important roles in brain ischemia and that the infiltration of blood-derived immune cells is a key initiator of this response. Nerve injury-induced protein 1 (Ninjurin 1, Ninj1) is a cell adhesion molecule responsible for cell-to-cell interactions between immune cells and endothelial cells. In the present study, we investigated the proinflammatory and neuroprotective effects of Ninj1 and a dodecamer peptide harboring Ninj1 N-terminal adhesion motif (N-NAM, Pro26~Asn37) in a rat middle cerebral artery occlusion (MCAO) model of stroke. Ninj1 was predominantly induced in neutrophils and endothelial cells in the ischemic hemispheres around 12 h to 1 day post-MCAO, which coincided with a massive neutrophil influx. We demonstrated that intranasal administration of Ninj1 small interfering RNA (siRNA) or N-NAM significantly blocked neutrophil infiltration in postischemic brains. In addition, intranasal administration of Ninj1 siRNA or N-NAM reduced the mean infarct volume to 46.5 ± 9.2 or 30.6 ± 11.7% of that of the PBS-treated MCAO controls, respectively, which was accompanied by significant amelioration of neurological and motor deficits. We showed that N-NAM or Ninj1 siRNA effectively blocked the adhesion and transendothelial migration of TNF-α-stimulated human myelocytic leukemia cells to human umbilical vein endothelial cells and similarly suppressed adhesion and migration of monocytes. Activations of phosphoinositide 3-kinase and Ras-related C3 botulinum toxin substrate 1 are involved in these Ninj1-mediated processes and can be inhibited by N-NAM or Ninj1 siRNA. These results indicate that Ninj1 plays an important role in neutrophil infiltration in the postischemic brain and N-NAM confers robust neuroprotective and anti-inflammatory effects by inhibiting Ninj1-mediated infiltration of neutrophils. [ABSTRACT FROM AUTHOR]

We report a working prototype of absolute distance meter developed for outer-space operation by incorporating a fiber-type modelocked laser. The target distance is measured using a 1 GHz synthetic radio frequency (~0.3 m wavelength) provided by the 20th intermode harmonic of a 50 MHz pulse repetition rate. The measurement repeatability is 7 μm at 1 s averaging with an accuracy of ±20 μm for a 2.5 m target distance. With a 100 Hz update rate, the measurement speed is fast enough to keep track of the target in motion with up to a 1.0 m/s velocity. The prototype is built within a compact volume of A4-size footprint to be feasible for the space mission of satellite-to-satellite distance measurement. [ABSTRACT FROM AUTHOR]

4-Hydroxybenzyl alcohol (4-HBA) is an important phenolic constituent of Gastrodia elata (GE) Blume, which is used as a traditional herbal medicine in East Asia. Many activities have been reported to underlie the beneficial effects of 4-HBA in brain, such as, anti-oxidative, anti-inflammatory, anti-excitotoxic, and anti-apoptotic effects in neurons and microglia. Here, the authors demonstrate the robust neuroprotective effects of 4-HBA in rat middle cerebral artery occlusion (MCAO) model of stroke, and showed anti-Zn2+ toxicity in neurons and astrocytes as a molecular mechanism contributing to these effects. Intraperitoneal administration of 4-HBA (20 mg/kg) in Sprague-Dawley rats 1 h after MCAO reduced infarct volumes to 27.1 ± 9.2% of that of MCAO controls and significantly ameliorated motor impairments and neurological deficits. Significant suppressions of Zn2+-induced cell death, ROS generation, and PARP-1 induction by 4-HBA were observed in primary cortical cultures. 4-HBA also protected astrocytes from Zn2+-induced toxicity and suppressing ROS generation by employing slightly different molecular mechanisms, i.e., suppressing PARP-1 induction and NAD depletion under acute Zn2+-treatment and suppressing p67 NADPH oxidase subunit induction under chronic Zn2+-treatment. Results indicate that the protective effects of 4-HBA against Zn2+-toxicity in neurons and astrocytes contribute to its robust neuroprotective effects in the postischemic brain. Considering the pleiotropic effects of 4-HBA, which have been reported in previous reports and added in the present study, it has therapeutic potential for the amelioration of ischemic brain damage. [ABSTRACT FROM AUTHOR]

Aortic atheroma is a known cause of ischemic stroke. However, it is unclear whether ischemic stroke is caused by emboli from aortic atheroma or by accompanying atherosclerosis. In this study, we evaluated lesion patterns of patients with complex aortic plaque (CAP) to assume the underlying pathophysiology. Acute ischemic stroke patients who underwent transesophageal echocardiography were included. CAP was defined as a plaque in the proximal aorta ≥ 4 mm thick or with a mobile component. The diffusion-weighted imaging lesion patterns of patients with CAP were compared to those with large arterial atherosclerosis (LAA) or cardioembolism (CE). A total of 64 CAP patients, 127 LAA patients, and 80 CE patients were included. Small cortical pattern was more common in the CAP group (45.3%) than in the LAA (7.9%, p < 0.001) or the CE group (23.8%, p = 0.018). A large cortical pattern was more common in the CE group than in the CAP group ( p < 0.001), whereas subcortical only pattern tended to be more common in the CAP group than in the CE group ( p = 0.057). In multinominal analysis, the CAP group was more likely to have a small cortical lesion than the LAA group [odds ratio (OR) 14.63; 95% confidence interval (CI) 4.67-45.85] or the CE (OR 3.69, 95% CI 1.19-11.39) group. In conclusion, patients with CAP frequently had small cortical lesions or subcortical single lesion. These findings imply that ischemic stroke in aortic atheroma patients is associated with either small emboli or small artery disease. [ABSTRACT FROM AUTHOR]

We review the progress made for compensation of the refractive index of air in laser-based distance measurements in the field of precision engineering. First, a comprehensive analysis is introduced to clarify how the overall measurement uncertainty is affected by the refractive index of the ambient air, particularly for dimensional metrology and geodetic survey using laser in open-air environment. Second, it is explained that the measurement uncertainty can be improved to a 10-8 level by adopting empirical dispersion formulae describing the relation of the laser wavelength with the environment parameters such as temperature, pressure, humidity and carbon dioxide concentration. Third, the principle of refractometers is given to describe that the measurement uncertainty can be enhanced to a 10-9 level by identifying the refractive index of air real time in well-controlled environmental conditions. Fourth, the two-color compensation method is discussed which enables precise laser-based distance measurement simply by using two different wavelengths without actual identification of the refractive index of open air. Finally, the recent approach of using femtosecond lasers is described with emphasis on the performance of the two-color method can be enhanced to a 10 level by stabilizing the pulse repetition rate as well as frequency stability of ultrashort pulse lasers with reference to the atomic clocks. [ABSTRACT FROM AUTHOR]

Osteopontin (OPN) is a phosphorylated glycoprotein possessing an arginine-glycine-aspartate (RGD)-motif, which binds to several cell surface integrins and mediates a wide range of cellular processes. Inductions of OPN have been reported in the postischemic brain, and the neuroprotective effects of OPN have been demonstrated in animal models of stroke. In the present study, we showed a robust neuroprotective effect of RGD-containing icosamer OPN peptide (OPNpt20) in a rat model of focal cerebral ischemia (middle cerebral artery occlusion, MCAO). Intranasally administered OPNpt20 reduced mean infarct volume by 79.7 % compared to the treatment-naïve MCAO control animals and markedly ameliorated neurological deficits. In addition, OPNpt20 significantly suppressed the inductions of iNOS and of inflammatory markers in postischemic brains and in primary microglial cultures, demonstrating anti-inflammatory effects. Administration of a mutant peptide, in which RGD was replaced by arginine-alanine-alanine (RAA), failed to suppress infarct volumes in MCAO animals and co-administration of OPNpt20 with anti-αβ integrin antibody failed to suppress iNOS induction in primary microglia culture, indicating that the RGD motif in OPNpt20 and endogenous αβ integrin play critical roles. Furthermore, pull-down assay revealed a direct binding between OPNpt20 and αβ integrin in primary microglia culture. Together, these results indicate that RGD-containing OPN icosamer has therapeutic potential in the postischemic brain and αβ integrin-mediated anti-inflammatory effect might be an underlying mechanism. [ABSTRACT FROM AUTHOR]

Expedient prediction of storm surge is required for emergency managers to make critical decisions for evacuation, structure closure, and other emergency responses. However, time-dependent storm surge models do not exist for fast and accurate prediction in very short periods on the order of seconds to minutes. In this paper, a time-dependent surrogate model of storm surge is developed based on an artificial neural network with synthetic simulations of hurricanes. The neural network between six input hurricane parameters and one target parameter, storm surge, is trained by a feedforward backpropagation algorithm at each of 92 uniform time steps spanning 45.5 h for each storm. The basis data consist of 446 tropical storms developed from a joint probability model that was based on historical tropical storm activity in the Gulf of Mexico. Each of the 446 storms was modeled at high fidelity using a coupled storm surge and nearshore wave model. Storm surge is predicted by the 92 trained networks for approaching hurricane climatological and track parameters in a few seconds. Furthermore, the developed surrogate model is validated with measured data and high-fidelity simulations of two historical hurricanes at four points in southern Louisiana. In general, the neural networks at or near the boundary between land and ocean are well trained and model predictions are of similar accuracy to the basis modeling suites. Networks based on modeling results from complex inland locations are relatively poorly trained. [ABSTRACT FROM AUTHOR]

Ultrashort extreme-ultraviolet pulses are a key tool in time-resolved spectroscopy for the investigation of electronic motion in atoms, molecules and solids. High-harmonic generation is a well-established process for producing ultrashort extreme-ultraviolet pulses by direct frequency upconversion of femtosecond near-infrared pulses. However, elaborate pump-probe experiments performed on the attosecond timescale require continuous efforts to improve the spatiotemporal coherence and also the repetition rate of the generated pulses. Here, we demonstrate a three-dimensional metallic waveguide for the plasmonic generation of ultrashort extreme-ultraviolet pulses by means of field enhancement using surface-plasmon polaritons. The intensity enhancement factor reaches a peak of ?350, allowing generation up to the 43rd harmonic in xenon gas, with a modest incident intensity of ?1 × 1011 W cm-2. The pulse repetition rate is maintained as high as 75 MHz without external cavities. The plasmonic waveguide is fabricated on a cantilever microstructure and is therefore suitable for near-field spectroscopy with nanometre-scale lateral selectivity. [ABSTRACT FROM AUTHOR]

In an underwater environment, measurements regarding true targets and false targets (clutter) can be made. Therefore, a suitable data association method to exactly detect and track a target and an efficient track initiation method for judging tracks formed by the target should be selected in this environment. This paper attempts to propose a new data association method and track initiation method to detect and track targets more effectively. Also, the performance of the new method is tested in a series of Monte Carlo simulation runs and is compared with the existing data association and track initiation methods in a cluttered environment. [ABSTRACT FROM AUTHOR]

High mobility group box 1 (HMGB1) was originally identified as ubiquitously expressed nonhistone DNA-binding protein, but recently, it was found to act as an endogenous danger molecule, which signals danger and traumatic cell death. Previously, the authors showed that HMGB1 is massively released immediately after an ischemic insult and that it subsequently activates microglia and induces inflammation in the postischemic brain. Here, we showed the endogenous danger molecule-like function of HMGB1 in primary cortical cultures. HMGB1 was found to be accumulated in NMDA-treated primary cortical culture media, and media collected from these cultures were able to induce neuronal cell death when added to fresh primary cortical cultures. However, HMGB1-depleted NMDA-conditioned media produced by HMGB1 siRNA transfection or by preincubation with anti-HMGB1 antibody or with HMGB1 A box failed to induce neuronal cell death. Furthermore, siRNA-mediated HMGB1 knockdown substantially suppressed NMDA- or Zn-induced cell death. It was interesting to find that extracellular HMGB1-induced neuronal apoptosis, as evidenced by TUNEL staining and caspase 3 assay in combination with double immunofluorescence staining. A series of RAGE and HMGB1 co-immunoprecipitation experiments in the presence of SB203580 and PD98059 (p38 MAPK and ERK inhibitors, respectively) demonstrated that RAGE-p38 MAPK and RAGE-ERK pathway might underlie extracellular HMGB1-mediated neuronal apoptosis. These results together with our previous reports regarding microglial activation by extracellular HMGB1 indicate that HMGB1 functions as a novel danger signal, which aggravates brain damage via autocrine and paracrine manners. [ABSTRACT FROM AUTHOR]

A significant process for highly precise measurement in 2-D inspection and 3D surface metrology is accurate and consistent imaging of target being measured. Dithering locking method, one of widely-used focus-locking method, has been only applied to objective modulation type which cause physical influence and image distortion. To overcome this, we have developed an actively locked focus-tracking system based around source dithering technique using fiber-optic confocal principle. Further, the whole measurement system can be simplified through both fiber confocal microscope design with reciprocity and fiber source modulation. It is verified that the proposed focus-tracking system has sub-μm focusing stability and accuracy. By testing focus tracking performance on a LCD panel substrate with a few μm-sized features, the applicability to optical profiler with vision inspection was confirmed. [ABSTRACT FROM AUTHOR]

Surface profiling and film thickness measurement play an important role for inspection in semi conductor industry. White light source had been used as scanning white light interferometry and spectrally resolved white light interferometry for determining surface and film thickness profile. These techniques however failed for thinner film. Recently, reflectometry and spectrally resolved white light interferometry was combined for the same. This technique used Fourier Transform for the calculation of phase in spectral domain with the use of Linnik interferometer. In this method a large amount of carrier offset (carrier fringes) is required to be effective. This carrier fringes in spectrally resolved white light interferometry was achieved by increasing the optical path difference between the test and the reference surface. But, Linnik interferometer cause defocusing problem to create these carrier fringes. We propose in this paper to combine reflectometry and spectrally resolved phase shifting interferometry for measurement of surface and film thickness profile with the use of Michelson objective. Michelson objective will be convenient to implement as compared to the Linnik type and the use of phase shifting interferometry does not necessarily need large number of fringes in the spectral domain. [ABSTRACT FROM AUTHOR]

αB-crystallin (α-BC), a member of the small heat-shock proteins (sHSP), is constitutively expressed in the vertebrate lens and in non-ocular tissues including the central nervous system (CNS). In this study we investigated the expression of α-BC in the rat brain after middle cerebral artery occlusion (MCAO). α-BC transcript and protein were transiently expressed 4 h after MCAO/reperfusion in the pyramidal neurons in the peri-infarct region of the ischemic hemisphere. Beginning 2 days after MCAO, significant α-BC induction appeared in reactive astrocytes in the penumbra, and this induction was sustained for several days. In addition, levels of MAPKAPK-2, one of the α-BC upstream kinases, and its phosphorylated form were upregulated gradually and peaked 4 days after ischemia/reperfusion injury. The immunohistochemical study indicated that α-BC was co-localized with MAPKAPK-2 and p-MAPKAPK-2. Furthermore, p38β MAPK, an upstream kinase of MAPKAPK-2, which has been known to be involved in compensatory responses to stress, was also co-localized with α-BC in the penumbra. Our results suggest that the p38β-dependent α-BC induction in neurons and astrocytes in the penumbra may play an important role in the postischemic brain. [ABSTRACT FROM AUTHOR]

We investigated in this paper the progression of a shock-wave reflected from a compression corner in a particle-laden gas medium using a TVD class numerical technique and a MacCormack scheme. For a gas-only flow, the numerical results agreed well with the existing experimental data, suggesting that the gas phase is correctively solved. The effect of particle size and mass fraction ratio is investigated for a dilute gas-particle flow. It has been shown that the shock-wave diffraction and the flow configuration after the shock can become remarkably different from the gas-only flow depending on the particle parameters. Relaxation phenomenon due to the momentum drag and the heat exchange between the gas and the particle phases is explained. [ABSTRACT FROM AUTHOR]

Nerve injury-induced protein 1 (Ninjurin 1, Ninj1) is a cell adhesion molecule responsible for cell-to-cell interactions between immune cells and endothelial cells. In our previous paper, we have shown that Ninj1 plays an important role in the infiltration of neutrophils in the postischemic brain and that the dodecamer peptide harboring the Ninj1 N-terminal adhesion motif (N-NAM, Pro26-Asn37) inhibits infiltration of neutrophils in the postischemic brain and confers robust neuroprotective and anti-inflammatory effects. In the present study, we examinedt the pro-angiogenic effect of N-NAM using human umbilical vein endothelial cells (HUVECs) and rat MCAO (middle cerebral artery occlusion) model of stroke. We found that N-NAM promotes proliferation, migration, and tube formation of HUVECs and demonstrate that the suppression of endogenous Ninj1 is responsible for the N-NAM-mediated pro-angiogenic effects. Importantly, a pull-down assay revealed a direct binding between exogenously delivered N-NAM and endogenous Ninj1 and it is N-terminal adhesion motif dependent. In addition, N-NAM activated the Ang1-Tie2 and AKT signaling pathways in HUVECs, and blocking those signaling pathways with specific inhibitors suppressed N-NAM-induced tube formation, indicating critical roles of those signaling pathways in N-NAM-induced angiogenesis. Moreover, in a rat MCAO model, intranasal administration of N-NAM beginning 4 days post-MCAO (1.5 µg daily for 3 days) augmented angiogenesis in the penumbra of the ipsilateral hemisphere of the brain and significantly enhanced total vessel lengths, vessel densities, and pro-angiogenic marker expression. These results demonstrate that the 12-amino acid Ninj1 peptide, which contains the N-terminal adhesion motif of Ninj1, confers pro-angiogenic effects and suggest that those effects might contribute to its neuroprotective effects in the postischemic brain. [ABSTRACT FROM AUTHOR]

Replying to M. Sivis, M. Duwe, B. Abel & C. Ropers 485, http://dx.doi.org/nature10978 (2012)Sivis et al. showed spectral data of extreme ultraviolet (EUV) emission from gas-exposed bow-ties, claiming high predominance of atomic line emission (ALE) of neutral and ionized gas atoms in contradiction to our data of high harmonic generation (HHG). This is not the first time the signature of ALE has been identified in conventional HHG spectral data. The two distinct phenomena, ALE and HHG, are not mutually exclusive but coexistent when gaseous atoms are illuminated by strong-field laser pulses. [ABSTRACT FROM AUTHOR]

Immune damages on the peripheral myelin sheath under pro-inflammatory milieu result in primary demyelination in inflammatory demyelinating neuropathy. Inflammatory cytokines implicating in the pathogenesis of inflammatory demyelinating neuropathy have been used for the development of potential biomarkers for the diagnosis of the diseases. In this study, we have found that macrophages, which induce demyelination, expressed a B-cell-recruiting factor CXC chemokine ligand 13 (CXCL13) in mouse and human inflammatory demyelinating nerves. The serum levels of CXCL13 were also higher in inflammatory demyelinating neuropathic patients but not in acute motor axonal neuropathy or a hereditary demyelinating neuropathy, Charcot-Marie-Tooth disease type 1a. In addition, CXCL13-expressing macrophages were not observed in the sciatic nerves after axonal injury, which causes the activation of innate immunity and Wallerian demyelination. Our findings indicate that the detection of serum CXCL13 will be useful to specifically recognize inflammatory demyelinating neuropathies in human. [ABSTRACT FROM AUTHOR]

Phase-coherent transfer of optical frequencies over a long distance is required for diverse photonic applications, including optical clock dissemination and physical constants measurement. Several demonstrations were made successfully over fiber networks, but not much work has been done yet through the open air where atmospheric turbulence prevails. Here, we use an 18 km outdoor link to transmit multiple optical carriers extracted directly from a frequency comb of a 4.2 THz spectral width. In stabilization to a high-finesse cavity with a 1.5 Hz linewidth, the comb-rooted optical carriers are simultaneously transferred with collective suppression of atmospheric phase noise to −80 dBc Hz−1. Microwaves are also delivered by pairing two separate optical carriers bound with inter-comb-mode coherence, for example a 10 GHz signal with phase noise of −105 dBc Hz−1 at 1 Hz offset. Lastly, an add-on demonstration is given for multi-channel coherent optical communications with the potential of multi-Tbps data transmission in free space. Phase-coherent transfer of optical frequencies over long open-air paths is necessary in photonic applications. Here the authors demonstrate the parallel transmission of multiple optical carriers in air up to 18 km using a stable near-infrared frequency comb. [ABSTRACT FROM AUTHOR]

Nonlinear susceptibilities are key to ultrafast lightwave driven optoelectronics, allowing petahertz scaling manipulation of the signal. Recent experiments retrieved a 3rd order nonlinear susceptibility by comparing the nonlinear response induced by a strong laser field to a linear response induced by the otherwise identical weak field. The highly nonlinear nature of high harmonic generation (HHG) has the potential to extract even higher order nonlinear susceptibility terms. However, up till now, such characterization has been elusive due to a lack of direct correspondence between high harmonics and nonlinear susceptibilities. Here, we demonstrate a regime where such correspondence can be clearly made, extracting nonlinear susceptibilities (7th, 9th, and 11th) from sapphire of the same order as the measured high harmonics. The extracted high order susceptibilities show angular-resolved periodicities arising from variation in the band structure with crystal orientation. Our results open a door to multi-channel signal processing, controlled by laser polarization. Characterizing higher order nonlinearities and responses to optical excitations in materials is challenging. Here, the authors use high harmonic generation in sapphire crystals to extract higher order susceptibilities and characterize the nonlinear electronic response directly from experimental measurements. [ABSTRACT FROM AUTHOR]

The risk of osteoporosis in patients with chronic inflammatory neuropathy (CIN) has not been evaluated in detail. We conducted a population-based case-control study nested in a retrospective cohort to analyze osteoporosis risk among patients with CIN using a nationwide database. Patients with CIN based on the Korean Classification of Disease diagnostic code were included and were matched to controls. A Cox proportional hazards regression model was used to evaluate the effect of CIN on osteoporosis. After propensity score matching, 585 CIN patients and 585 controls were selected. Patients with CIN had an increased osteoporosis risk (hazard ratio [HR] = 2.293, 95% confidence interval [CI] 1.460–3.601) compared with controls. The osteoporosis risk was higher among male patients with CIN than among male controls (HR = 5.404, 95% CI 2.252–12.969), while there were no significant differences among women. Among the CIN patients, the average daily dose of corticosteroids was higher in those who developed osteoporosis (19.6 mg [10.8–49.3]) than those who did not (16.2 mg [7.2–29.1], p = 0.001). The osteoporosis risk among CIN patients is higher than among controls. High risk of osteoporosis in male patients may indicate that osteoporosis in CIN patients results from the disease itself or related treatments. [ABSTRACT FROM AUTHOR]

Ethyl pyruvate (EP) is a simple aliphatic ester of pyruvic acid and has been shown to have robust neuroprotective effects via its anti-inflammatory, anti-oxidative, and anti-apoptotic functions. In an effort to develop novel EP derivatives with greater protective potencies than EP, we generated four EP isosteres, among them the neuroprotective potency of N,N-diethyl-2-oxopropanamide (DEOPA), in which the ethoxy group of EP was replaced with diethylamine, was far greater than that of EP. When DEOPA was administered intravenously (5 mg/kg) to rat middle cerebral artery occlusion (MCAO) model at 6 hrs post-surgery, it suppressed infarct formation, ameliorated neurological and sensory/motor deficits, and inhibited microglial activation and neutrophil infiltrations in the postischemic brain more effectively than EP. In particular, DEOPA markedly suppressed LPS-induced nitrite production and cytokine/chemokine inductions in microglia, neutrophils, and endothelial cells and these effects are attributable to inhibition of the activity of NF-κB by suppressing IκB-α degradation and p65 to DNA binding. In addition, DEOPA suppressed NMDA-induced neuronal cell death in primary cortical neuron cultures by NAD replenishment and suppression of NF-κB activity. Together, these results indicate DEOPA has multi-modal protective effects against ischemic brain damage targeting numerous cell types in the brain and also against other inflammation-related diseases. [ABSTRACT FROM AUTHOR]

Femtosecond lasers allow for simultaneous detection of multiple absorption lines of a specimen over a broad spectral range of infrared or visible light with a single spectroscopic measurement. Here, we present an 8-THz bandwidth, 0.5-GHz resolution scheme of Fourier-transform spectroscopy using an Er-doped fiber femtosecond laser. A resolving power of 1.6 × 104 about a 1560-nm center wavelength is achieved by sweeping the pulse repetition rate of the light source on a fiber Mach-Zehnder interferometer configured to capture interferograms with a 0.02-fs temporal sampling accuracy through a well-stabilized 60-m unbalance arm length. A dual-servo mechanism is realized by combining a mechanical linear stage with an electro-optic modulator (EOM) within the fiber laser cavity, enabling stable sweeping control of the pulse repetition rate over a 1.0-MHz scan range with 0.4-Hz steps with reference to the Rb clock. Experimental results demonstrate that the P-branch lines of the H13CN reference cell can be observed with a signal-to-noise ratio reaching 350 for the most intense line. [ABSTRACT FROM AUTHOR]

Stabilizing a frequency comb to an ultra-stable optical frequency reference requires a multitude of optoelectronic peripherals that have to operate under strict ambient control. Meanwhile, the frequency comb-to-comb stabilization aims to synchronize a slave comb to a well-established master comb with a substantial saving in required equipment and efforts. Here, we report an utmost case of frequency comb-to-comb stabilization made through a 1.3 km free-space optical (FSO) link by coherent transfer of two separate comb lines along with a feedback suppression control of atmospheric phase noise. The FSO link offers a transfer stability of 1.7 × 10 -15 at 0.1 s averaging, while transporting the master comb's stability of 1.2 × 10 -15 at 1.0 s over the entire spectrum of the slave comb. Our remote comb-to-comb stabilization is intended to expedite diverse long-distance ground-to-ground or ground-to-satellite applications; as demonstrated here for broadband molecular spectroscopy over a 6 THz bandwidth as well as ultra-stable microwaves generation with phase noise of -80 dBc Hz -1 at 1 Hz., (© 2022. The Author(s).)