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Pain perception can be altered by activity in the periaqueductal gray (PAG). The PAG can decrease the incoming nociceptive signals at the level of the spinal dorsal horn, but it is not clear whether the PAG can also affect the sensory thalamus, ventral posterolateral and ventral posteromedial thalamic nuclei, to modulate pain. However, the PAG and the thalamus have direct connections with each other; so we postulated that the PAG may also modulate pain by inhibiting the sensory nuclei in the thalamus, and that these may also reciprocally influence the PAG. Here, by analyzing the local field potentials recorded from the sensory thalamus and the PAG in chronic pain patients with deep brain stimulation electrodes, we show that PAG stimulation inhibited the sensory thalamus with decreasing thalamic delta, theta, alpha and beta power, and sensory thalamus stimulation excited the PAG with increasing PAG delta and theta power. We demonstrate that the PAG and the sensory thalamus interact reciprocally at short latency, which may be related to pain modulation. [ABSTRACT FROM AUTHOR]

Abstract: Background: The midbrain periaqueductal and periventricular gray (PAVG) region is important for pain and autonomic modulation. We have previously described changes in blood pressure dependent upon dorsal or ventral electrode positioning with PAVG deep brain stimulation (DBS), yet controversy exists about whether DBS acts via endogenous opioid release. Method and results: We combined local field potential (LFP) recording from PAVG DBS electrodes in humans with naloxone and saline infusions to determine whether dorsal and ventral PAVG DBS act through opioidergic or other mechanisms. Four awake human subjects were investigated. DBS were implanted contralateral to the painful body part. Electrode contact positions were mapped using MRI and brain atlas information. Naloxone then saline were randomly administered to the blinded subjects and pain rated using a numeric pain rating scale at 30s intervals for 3min. Two subjects received dorsal DBS electrodes and two had ventral placements. Significantly elevated gamma frequency band (30–90Hz) power concomitant with pain exacerbation was found with naloxone versus both saline and rest in dorsal not ventral PAVG LFPs (p <0.005). Significantly elevated delta frequency band (0–4Hz) power (p =0.001) was seen in one ventral PAVG subject with both naloxone and saline infusions. Conclusions: Dorsal PAVG DBS may reduce pain by augmenting endogenous opioid release. Elevated gamma oscillations enhance awareness of worsening pain with opioid blockade. Ventral PAVG DBS may act by separate possibly autonomic mechanisms. Increased delta oscillations indicate a survival rhythm involved in the initiation of passive coping responses to homeostatic changes. [Copyright &y& Elsevier]

Abstract: We report a novel post-loading approach for constructing a multifunctional biodegradable polyacrylamide (PAA) nanoplatform for tumor-imaging (fluorescence) and photodynamic therapy (PDT). This approach provides an opportunity to post-load the imaging and therapeutic agents at desired concentrations. Among the PAA nanoparticles, a formulation containing the photosensitizer, HPPH [3-(1′-hexyloxyethyl)pyropheophorbide-a], and the cyanine dye in a ratio of 2:1 minimized the undesirable quenching of the HPPH electronic excitation energy because of energy migration within the nanoparticles and/or Förster (fluorescence) resonance energy transfer (FRET) between HPPH and cyanine dye. An excellent tumor-imaging (NIR fluorescence) and phototherapeutic efficacy of the nanoconstruct formulation is demonstrated. Under similar treatment parameters the HPPH in 1% Tween 80/5% aqueous dextrose formulation was less effective than the nanoconstruct containing HPPH and cyanine dye in a ratio of 2 to 1. This is the first example showing the use of the post-loading approach in developing a nanoconstructs for tumor-imaging and therapy. From the Clinical Editor: Fluorescence imaging is a rapidly evolving and relatively high-throughput tool currently only utilized in preclinical imaging. The authors of this work demonstrate a tumor-specific florescence imaging nanoplatform that enables not only imaging, but photodynamic therapy as well. [Copyright &y& Elsevier]

Objective: Established methods for predicting speech recognition in noise require knowledge of clean speech signals, placing limitations on their application. The study evaluates an alternative approach based on characteristics of noisy speech, specifically its sparseness as represented by the statistic kurtosis. Design: Experiments 1 and 2 involved acoustic analysis of vowel-consonant-vowel (VCV) syllables in babble noise, comparing kurtosis, glimpsing areas, and extended speech intelligibility index (ESII) of noisy speech signals with one another and with pre-existing speech recognition scores. Experiment 3 manipulated kurtosis of VCV syllables and investigated effects on speech recognition scores in normal-hearing listeners. Study sample: Pre-existing speech recognition data for Experiments 1 and 2; seven normal-hearing participants for Experiment 3. Results: Experiments 1 and 2 demonstrated that kurtosis calculated in the time-domain from noisy speech is highly correlated (r > 0.98) with established prediction models: glimpsing and ESII. All three measures predicted speech recognition scores well. The final experiment showed a clear monotonic relationship between speech recognition scores and kurtosis. Conclusions: Speech recognition performance in noise is closely related to the sparseness (kurtosis) of the noisy speech signal, at least for the types of speech and noise used here and for listeners with normal hearing. [ABSTRACT FROM AUTHOR]

Objective: Kawasaki disease (KD) is characterized by systemic vasculitis of an unknown cause. A previous study has indicated that a polymorphism of the inositol 1,4,5-trisphosphate 3-kinase C ( ITPKC) gene is involved in the susceptibility to KD. ORAI (also known as CRACM1) is one of the components of store-operated calcium channels involved in regulating immune and inflammatory reactions. This study was conducted to investigate if polymorphisms in ORAI1/CRACM1, a gene downstream from ITPKC, are associated with KD susceptibility and clinical outcomes. Materials and Methods: A total of 1,056 subjects (341 KD patients and 715 controls) were investigated to identify five tagging single nucleotide polymorphisms (tSNPs) in ORAI1/CRACM1 (rs12313273, rs6486795, rs7135617, rs12320939, and rs712853) by using the TaqMan Allelic Discrimination assay. Results: No significant associations between genotype and allele frequency of the five ORAI1/CRACM1 tSNPs were observed in the KD patients and controls. In KD patients, no significant associations between ORAI1/CRACM1 polymorphisms and coronary artery lesion (CAL) formation or intravenous immunoglobulin (IVIG) treatment response were observed. The results from haplotype analysis were insignificant. Conclusions: This study showed for the first time that ORAI1/CRACM1 polymorphisms are not associated with KD susceptibility, CAL formation, or IVIG treatment response in the Taiwanese population. [ABSTRACT FROM AUTHOR]

Abstract: γ-Manganese dioxide nanorods were prepared using a simple hydrothermal method based on redox reactions between S2O8 2− and Mn2+ and decoration of silver nanoparticles was performed by a wet impregnation method. The as-prepared materials were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). Electrochemical discharging capacity of Ag/MnO2, MnO2/multi-walled carbon nanotubes (MWNTs), and Ag/MnO2/MWNTs electrodes were determined at 0.1C discharging rate. The results showed that utility efficiency of MnO2 was greatly enhanced when silver particles were introduced and there was strong interaction between silver nanoparticles and bulk MnO2 materials. Electrochemical impedance spectroscopy (EIS) measurements were performed to investigate the discharging mechanism of the Ag/MnO2/MWNTs electrodes. Silver nanoparticles not only enhanced electronic conductivity of the network, but also improved proton diffusion process. [Copyright &y& Elsevier]

Climate change is known to significantly affect vegetation development in the terrestrial system. Because Southwest China (SW) is affected by westerly winds and the South and East Asian monsoon, its climates are complex and changeable, and the time lag effect of the vegetation's response to the climate has been rarely considered, making it difficult to establish a link between the SW region's climate variables and changes in vegetation growth rate. This study revealed the characteristics of the time lag reaction and the phased changes in the response of vegetation to climate change across the entire SW and the typical climate type core area (CA) using the moving average method and multiple linear model based on the climatic information of CRU TS v. 4.02 from 1982 to 2017 together with the annual maximum (P100), upper quarter quantile (P75), median (P50), lower quarter quantile (P25), minimum (P5), and mean (Mean) from GIMMS NDVI. Generally, under the single and combined effects of temperature and precipitation, taking the time lag effect (annual and interannual delay effect) into account significantly improved the average prediction rates of temperature and precipitation, which increased by 18.48% and 25.32%, respectively. The optimal time delay was 0–4 months when the annual delay was taken into consideration, but it differed when considering the interannual delay, and the delaying effect of precipitation was more significant than that of temperature. Additionally, the response intensity of vegetation to temperature, precipitation, and their interaction was significantly more robust when the annual delay was taken into account than when it was not (p < 0.05), with corresponding multiple correlation coefficients of 0.87 and 0.91, respectively. However, the degree of response to the combined effect of individual effects and climate factors tended to decrease regardless of whether time delay effects were taken into account. A more comprehensive analysis of the effects of climate change on vegetation development dynamics suggested that the best period for synthesizing NDVI annual values might be the P25 period. Our study could provide a new theoretical framework for analyzing, predicting, and evaluating the dynamic response of vegetation growth to climate change. [ABSTRACT FROM AUTHOR]

Objective. To investigate the effects of quantitative nursing and psychological interventions on stress response, mental health, and prognosis in endometrial cancer patients having laparoscopic surgery. Methods. The random number table approach was used to identify and split 98 patients with endometrial cancer undergoing laparoscopic surgery at our hospital's Obstetrics and Gynecology Hospital (n = 49) into observation and control groups (n = 49) from May 2020 to February 2022. Both groups received standard care in the operating room, while those in the observation group received quantitative and psychological interventions in the operating room. Both groups were compared for perioperative markers, stress indicators, coping strategies, and pain levels. Results. In terms of age, TNM stage, or pathology, there was no statistically significant difference between the two groups (P > 0.05). Both the observation and control groups experienced statistically significant (P < 0.05) reductions in the perioperative markers of operation time, intraoperative blood loss, and overall hospital stay. Both groups' SAS and SDS scores were lower than they had been prior to surgery, but the observation group had lower scores than the control group, and these differences were statistically significant (P < 0.05). Postsurgery, the observation group's cortisol and adrenaline levels were lower than those of the control group, and both groups' levels were higher than before surgery, with statistical significance (P < 0.05) in both groups. Neither coping style nor pain level differed significantly between the two groups before surgery (P > 0.05). Postoperatively, while yield item scores were lower and faces scores were higher than the control group, the observation group's avoidance item score was lower than the control group. All with statistical significance. There were substantial differences in NRS SCORE between observers and controls. Conclusion. After laparoscopic surgery to remove endometrial cancer, patients may benefit from the combination of quantitative nursing and psychological intervention in the operating room to alleviate postoperative anxiety and sadness and reduce stress reaction. [ABSTRACT FROM AUTHOR]

Methylated CpG binding protein 2 (MeCP2) plays an important role in the development and normal function of the neural system. Abnormally high expression of MECP2 leads to a subtype of autism called MECP2 duplication syndrome and MECP2 is considered one of the key pathogenic genes for autism spectrum disorders. However, the effect of MECP2 overexpression on neural activity is still not fully understood. Thus, transgenic (TG) animals that abnormally overexpress MeCP2 are important disease models in research on neurological function and autism. To create an animal model with a stronger and more stable autism phenotype, this study established a human MECP2 TG rat model and evaluated its movement ability, anxiety, and social behavior through behavioral tests. The results showed that MECP2 TG rats had an abnormally increased anxiety phenotype and social deficits in terms of abnormal social approach and social novelty preference, but no movement disorder. These autism-like behavioral phenotypes suggest that human MECP2 TG rats are suitable models for studying autism as they show more severe social deficit phenotypes and without interference from movement disorders affecting other phenotypes, which is an issue for mouse models with MECP2 duplication. In addition, this study performed preliminary exploration of the influence of the human MECP2 transgene on neural oscillation stability of the medial prefrontal cortex (mPFC), which is an important brain region for social interactions. Oscillation stability in MECP2 TG rats showed abnormal responses to social conditions. Overall, the results of this study provide a new research tool for understanding the mechanism of social impairment and treatment of autism. The results also provide evidence for the influence of MECP2 duplication on mPFC neural activity. • Human MECP2 TG rats have an abnormally increased anxiety phenotype. • Human MECP2 TG rats show significant social deficit phenotypes. • Human MECP2 TG rats do not exhibit movement disorders and stereotypical orientation preference. • Oscillation stability in MECP2 TG rats show abnormal responses to social conditions. [ABSTRACT FROM AUTHOR]

Although previous studies have reported correlations between alpha oscillations and the "retention" subprocess of working memory (WM), causal evidence has been limited in human neuroscience due to the lack of delicate modulation of human brain oscillations. Conventional transcranial alternating current stimulation (tACS) is not suitable for demonstrating the causal evidence for parietal alpha oscillations in WM retention because of its inability to modulate brain oscillations within a short period (i.e., the retention subprocess). Here, we developed an online phase-corrected tACS system capable of precisely correcting for the phase differences between tACS and concurrent endogenous oscillations. This system permits the modulation of brain oscillations at the target stimulation frequency within a short stimulation period and is here applied to empirically demonstrate that parietal alpha oscillations causally relate to WM retention. Our experimental design included both in-phase and anti-phase alpha-tACS applied to participants during the retention subprocess of a modified Sternberg paradigm. Compared to in-phase alpha-tACS, anti-phase alpha-tACS decreased both WM performance and alpha activity. These findings strongly support a causal link between alpha oscillations and WM retention and illustrate the broad application prospects of phase-corrected tACS. With its capacity to correct for its phase differences relative to concurrent brain oscillations, an online phase-corrected tACS system provides the possibility to both up- and down-regulate targeted brain oscillations within a short period; using such a system, this study shows that parietal alpha oscillations exert causal impacts on working memory retention. [ABSTRACT FROM AUTHOR]

Autophagy has been implicated in stroke. Our previous study showed that the FoxO3 transcription factor promotes autophagy after transient cerebral ischemia/reperfusion (I/R). However, whether the Akt/FoxO3 signaling pathway plays a regulatory role in autophagy in cerebral I/R-induced oxidative stress injury is still unclear. The present study aims to investigate the effects of the Akt/FoxO3 signaling pathway on autophagy activation and neuronal injury in vitro and in vivo. By employing LY294002 or insulin to regulate the Akt/FoxO3 signaling pathway, we found that insulin pretreatment increased cell viability, decreased reactive oxygen species production, and enhanced the expression of antiapoptotic and autophagy-related proteins following H2O2 injury in HT22 cells. In addition, insulin significantly decreased neurological deficit scores and infarct volume and increased the expression of antiapoptotic and autophagy-related proteins following I/R injury in rats. However, LY294002 showed the opposite effects under these conditions. Altogether, these results indicate that Akt/FoxO3 signaling pathway activation inhibited oxidative stress-mediated cell death through activation of autophagy. Our study supports a critical role for the Akt/FoxO3 signaling pathway in autophagy activation in stroke. [ABSTRACT FROM AUTHOR]

Deep brain stimulation (DBS) targeting the globus pallidus internus (GPi) and subthalamic nucleus (STN) is employed for the treatment of dystonia. Pallidal low-frequency oscillations have been proposed as a pathophysiological marker for dystonia. However, the role of subthalamic oscillations and STN-GPi coupling in relation to dystonia remains unclear. We aimed to explore oscillatory activities within the STN-GPi circuit and their correlation with the severity of dystonia and efficacy achieved by DBS treatment. Local field potentials were recorded simultaneously from the STN and GPi from 13 dystonia patients. Spectral power analysis was conducted for selected frequency bands from both nuclei, while power correlation and the weighted phase lag index were used to evaluate power and phase couplings between these two nuclei, respectively. These features were incorporated into generalized linear models to assess their associations with dystonia severity and DBS efficacy. The results revealed that pallidal theta power, subthalamic beta power and subthalamic-pallidal theta phase coupling and beta power coupling all correlated with clinical severity. The model incorporating all selected features predicts empirical clinical scores and DBS-induced improvements, whereas the model relying solely on pallidal theta power failed to demonstrate significant correlations. Beyond pallidal theta power, subthalamic beta power, STN-GPi couplings in theta and beta bands, play a crucial role in understanding the pathophysiological mechanism of dystonia and developing optimal strategies for DBS. • Low-frequency and beta oscillations and couplings in the STN-GPi circuit are associated with dystonia severity. • The same set of oscillatory features within the STN-GPi circuit reflect DBS- induced improvements. • Pallidal low-frequency oscillation alone may not fully explain dystonia severity and DBS efficacy. [ABSTRACT FROM AUTHOR]

Neural oscillations are critical to understanding the synchronisation of neural activities and their relevance to neurological disorders. For instance, the amplitude of beta oscillations in the subthalamic nucleus has gained extensive attention, as it has been found to correlate with medication status and the therapeutic effects of continuous deep brain stimulation in people with Parkinson's disease. However, the frequency stability of subthalamic nucleus beta oscillations, which has been suggested to be associated with dopaminergic information in brain states, has not been well explored. Moreover, the administration of medicine can have inverse effects on changes in frequency and amplitude. In this study, we proposed a method based on the stationary wavelet transform to quantify the amplitude and frequency stability of subthalamic nucleus beta oscillations and evaluated the method using simulation and real data for Parkinson's disease patients. The results suggest that the amplitude and frequency stability quantification has enhanced sensitivity in distinguishing pathological conditions in Parkinson's disease patients. Our quantification shows the benefit of combining frequency stability information with amplitude and provides a new potential feedback signal for adaptive deep brain stimulation. • The new quantification AFS comprehensively captures variations in amplitude and frequency stability of neural oscillations. • AFS quantification indicates better correlation than amplitude or frequency stability with symptom alleviation. • AFS can be implemented in real-time for adaptive deep brain stimulation. [ABSTRACT FROM AUTHOR]