In Situ Probing the Structure Change and Interaction of Interfacial Water and Hydroxyl Intermediates on Ni(OH)2 Surface over Water Splitting.

There is growing acknowledgment that the properties of the electrochemical interfaces play an increasingly pivotal role in improving the performance of the hydrogen evolution reaction (HER). Here, we present, for the first time, direct dynamic spectral evidence illustrating the impact of the interaction between interfacial water molecules and adsorbed hydroxyl species (OHad) on the HER properties of Ni(OH)2 using Au/core-Ni(OH)2/shell nanoparticle-enhanced Raman spectroscopy. Notably, our findings highlight that the interaction between OHad and interfacial water molecules promotes the formation of weakly hydrogen-bonded water, fostering an environment conducive to improving the HER performance. Furthermore, the participation of OHad in the reaction is substantiated by the observed deprotonation step of Au@2 nm Ni(OH)2 during the HER process. This phenomenon is corroborated by the phase transition of Ni(OH)2 to NiO, as verified through Raman and X-ray photoelectron spectroscopy. The significant redshift in the OH-stretching frequency of water molecules during the phase transition confirms that surface OHad disrupts the hydrogen-bond network of interfacial water molecules. Through manipulation of the shell thickness of Au@Ni(OH)2, we additionally validate the interaction between OHad and interfacial water molecules. In summary, our insights emphasize the potential of electrochemical interfacial engineering as a potent approach to enhance electrocatalytic performance.

Oral frailty: a concept analysis.

BACKGROUND: Oral frailty has become a worldwide problem among older adults. Although researchers have conducted various studies on oral frailty, its definition remains controversial. PURPOSE: To clarify the concept of oral frailty. METHODS: Online databases PubMed, Web of Science, CINAHL, Cochrane Library, ProQuest, China National Knowledge Infrastructure (CNKI), China Science and Technology Journal Database (VIP), and Wanfang database were searched from inception to September 20, 2023. The reference lists of relevant studies were searched manually. Eligible articles, theses, and books were analyzed using Walker & Avant's concept analysis model. RESULTS: The attributes of oral frailty were abnormal oral structure and/or decline in multi-faceted oral function and coexisting decline in physical, cognitive and social functions. Its antecedents were aging, social frailty, and severe periodontitis, whereas its consequences were decline in physical health and mental health, social withdrawal, lower quality of life and systemic frailty. CONCLUSION: Oral frailty could result in worse conditions among older adults physically, psychologically and socially. Tools based on the concept analysis need to be developed to comprehensively assess oral frailty.

The effect of enteral nutrition nursing intervention on postoperative treatment of chronic critically ill patients: Health prevention data analysis.

The field of genomics has witnessed remarkable advancements, leading to the gradual clarification of the genetic mechanism underlying various cancers. As a result, there has been an increased emphasis on gene prevention and treatment. Against this backdrop, this paper aims to examine the impact of enteral nutrition nursing intervention on the postoperative treatment of patients with chronic critical illness, with a focus on health prevention. Based on an analysis of the clinical data of patients with chronic critical illness, the study found that enteral nutrition nursing intervention plays a crucial role in enhancing the nutritional status of patients, reducing the incidence of complications, shortening the length of hospital stay, and improving the effect of postoperative rehabilitation. The study's results provide valuable insights into the efficacy of enteral nutrition nursing intervention in the postoperative treatment of patients with chronic critical illness. By improving the nutritional status of patients, enteral nutrition nursing intervention can help reduce the risk of complications, shorten the length of hospital stay, and enhance the effectiveness of postoperative rehabilitation. These findings underscore the importance of adopting effective interventions such as enteral nutrition nursing to improve the therapeutic outcomes of chronic critical illness patients and achieve the goal of health prevention.

Unsupervised Noise Reductions for Gravitational Reference Sensors or Accelerometers Based on the Noise2Noise Method.

Onboard electrostatic suspension inertial sensors are important applications for gravity satellites and space gravitational-wave detection missions, and it is important to suppress noise in the measurement signal. Due to the complex coupling between the working space environment and the satellite platform, the process of noise generation is extremely complex, and traditional noise modeling and subtraction methods have certain limitations. With the development of deep learning, applying it to high-precision inertial sensors to improve the signal-to-noise ratio is a practically meaningful task. Since there is a single noise sample and unknown true value in the measured data in orbit, odd-even sub-samplers and periodic sub-samplers are designed to process general signals and periodic signals, and adds reconstruction layers consisting of fully connected layers to the model. Experimental analysis and comparison are conducted based on simulation data, GRACE-FO acceleration data, and Taiji-1 acceleration data. The results show that the deep learning method is superior to traditional data smoothing processing solutions.

Effects of leukocytospermia on the outcomes of assisted reproductive technology.

Leukocytospermia is one of the common causes of male infertility, and its effects on the clinical outcomes of assisted reproduction are controversial. There are no recommendations for the management of leukocytospermia in cases of assisted reproductive technology (ART). To investigate the impact of leukocytospermia on ART, we retrospectively compared the clinical outcomes in ART couples with or without leukocytospermia and further analysed the impact of the insemination method itself by split insemination treatment in ART couples with leukocytospermia. In this study, leukocytospermia was detected in 133 patients, namely 63 in the conventional in vitro fertilization (IVF) group, 38 in the intracytoplasmic sperm injection (ICSI) group and 32 in the split insemination group. Leukocytospermia has a negative influence on the parameters of semen samples; however, leukocytospermia did not affect the clinical outcomes of IVF or ICSI. Different insemination methods did not affect the fertilization, clinical pregnancy or live birth rates. In the split insemination study, no significant differences in clinical pregnancy and live birth rates between the IVF and ICSI groups were found; however, the numbers of two pronuclei (2PN), available embryos and good-quality embryos in the ICSI group were higher than those in the IVF group. Leukocytospermia may be a risk factor affecting semen parameters, and more attention should be given to IVF insemination. Leukocytospermia has no significant negative effect on the outcomes of ART. ICSI may obtain better embryos than IVF, but it cannot improve the clinical pregnancy and live birth rates.

Direct and Simultaneous Identification of Multiple Mitochondrial Reactive Oxygen Species in Living Cells Using a SERS Borrowing Strategy.

Identification of different mitochondrial reactive oxygen species (ROS) simultaneously in living cells is vital for understanding the critical roles of different ROS in biological processes. To date, it remains a great challenge to develop ROS probes for direct and simultaneous identification of multiple ROS with high specificity. Herein, we report a SERS-borrowing-strategy-based nanoprobe (Au@Pt core-shell nanoparticles) for simultaneous and direct identification of different ROS by their distinct Raman fingerprints. Isotope substitution experiments and DFT calculations confirmed the ability of Au@Pt nanoprobe to capture and identify different mitochondrial ROS (i.e. ⋅OOH, H2 O2 , and ⋅OH). When functionalized with triphenylphosphine (TPP), the Au@Pt-TPP nanoprobe located to mitochondria and detected multiple ROS simultaneously in living cells under oxidative stimulation. Our method offers a new tool for the study of the functions of various ROS in biological processes.

Irisin promotes proliferation but inhibits differentiation in osteoclast precursor cells.

The receptor activator of NF-κB ligand-induced osteoclast differentiation has a critical role in the process of bone metabolism. Overactivation of osteoclastogenesis may result in a series of diseases. Irisin, a novel myokine, which was first reported in 2012, has been proposed to mediate the beneficial metabolic effects of exercise. Studies have demonstrated that irisin targets osteoblasts by promoting osteoblast proliferation and differentiation; however, the underlying mechanism regarding the effect of irisin on osteoclasts remains elusive. Using 2 types of osteoclast precursor cells, RAW264.7 cells and mouse bone marrow monocytes, we showed that irisin promoted osteoclast precursor cell proliferation but inhibited osteoclast differentiation. Irisin down-regulated the expression of osteoclast differentiation marker genes, including receptor activators of NF-κB, nuclear factor of activated T cells, cytoplasmic 1, cathepsin K, and tartrate-resistant acid phosphatase (TRAP), as well as decreasing the number of TRAP-positive multinucleated cells and hydroxyapatite resorption pits. Furthermore, we showed that irisin suppressed the NF-κB signaling pathway, but activated the p38 and JNK signaling pathways. In the presence of an inhibitor of p38 and JNK, irisin-induced promotion of RAW264.7 cell proliferation was attenuated. However, irisin-induced inhibition of osteoclast differentiation was not affected by either the p38 or JNK signaling pathway. Our study suggested the direct effect of irisin on osteoclastogenesis and revealed the mechanism responsible for the therapeutic potential of irisin in bone metabolism disease.-Ma, Y., Qiao, X., Zeng, R., Cheng, R., Zhang, J., Luo, Y., Nie, Y., Hu, Y., Yang, Z., Zhang, J., Liu, L., Xu, W., Xu, C. C., Xu, L. Irisin promotes proliferation but inhibits differentiation in osteoclast precursor cells.

The association between the environmental endocrine disruptor bisphenol A and polycystic ovary syndrome: a systematic review and meta-analysis.

OBJECTIVE: To investigate the association between bisphenol A (BPA) and polycystic ovary syndrome (PCOS). METHODS: A systematic review and meta-analysis using STATA software for observational studies. RESULTS: Nine studies involving 493 PCOS patients and 440 controls were included in this review. The meta-analysis demonstrated that PCOS patients had significantly higher BPA levels compared with control groups (standardized mean difference (SMD): 2.437, 95% confidence interval (CI): (1.265, 3.609), p < .001). For studies of serum samples detected by enzyme-linked immunosorbent assay (ELISA), subgroup analyses according to ethnicity, body mass index (BMI), sample size, detection method (high-performance liquid chromatography (HPLC) and ELISA), PCOS-to-control ratio and study quality displayed that high BPA levels were significantly associated with Caucasian PCOS patients (SMD: 0.615, 95% CI: (0.308, 0.922), p < .001), high BMI (SMD: 0.512, 95% CI: (0.180, 0.843), p = .002), high quality (SMD: 0.624, 95% CI: (0.391, 0.856), p < .001), and high HOMA-IR (SMD: 0.467, 95% CI: (0.121, 0.813), p = .008). CONCLUSIONS: Serum BPA may be positively associated with women with PCOS and BPA might be involved in the insulin-resistance and hyperandrogenism of PCOS. More evidence from high quality studies, advanced detection methods, and larger cohorts for observational trials are needed to further confirm the association between BPA and PCOS.

Chromosomal polymorphisms are associated with female infertility and adverse reproductive outcomes after infertility treatment: a 7-year retrospective study.

Data from 19,950 women were retrospectively analysed to determine the effect of chromosomal polymorphisms on female infertility and pregnancy outcome; fertile women were used as controls. Frequency of chromosomal polymorphisms and adverse pregnancy outcomes were compared between groups. A significantly higher incidence of chromosomal polymorphisms was found in total infertile patients, and patients with tubal infertility, ovulatory dysfunction, cervical and uterine abnormalities, and unexplained infertility compared with controls (5.53% [P < 0.001], 4.86% [P = 0.012] 5.40% [P < 0.001], 5.75% [P < 0.001] and 8.51% [P < 0.001], versus 3.74%, respectively). Infertile women had a higher incidence of 9qh+ and inv(9) compared with controls (P < 0.001 and P = 0.027). Logistic regression analysis showed an effect of chromosomal polymorphisms on female infertility (adjusted OR 1.662, 95% CI 1.551 to 1.796, P < 0.001). All couples reported a phenotypically normal baby. In control and tubal infertility groups, miscarriage rates were higher in women with chromosomal polymorphisms than in women with normal chromosomes (4.95% versus 0.96%, P = 0.001 and 6.17% versus 1.08%, P < 0.001). Preterm birth rate showed a similar trend. Chromosomal polymorphisms adversely affected spontaneous miscarriage rates (adjusted OR 1.625, 95% CI 1.514 to 1.769, P = 0.005).

Estradiol therapy and breast cancer risk in perimenopausal and postmenopausal women: a systematic review and meta-analysis.

OBJECTIVE: To investigate the association between estradiol therapy and incidence of breast cancer, taking into consideration of different types of combined progestogen, the duration of exposure and the type of regimen. METHOD: A systematic review and meta-analysis. RESULT: A total of 14 studies were included in our study. In estradiol-only therapy analysis, meta-analysis resulted a pooled OR =0.90, 95% CI (0.40, 2.02) from the RCTs and pooled OR = 1.11, 95% CI (0.98, 1.27) from observational studies. However, in the analysis of estradiol-progestogen therapy, the risk of breast cancer varies according to the type of progestogen and the duration with more than five years (OR = 2.43, 95% CI (1.79, 3.29)) presented a higher risk than using less than five years (OR = 1.49, 95% CI (1.03, 2.15)). CONCLUSIONS: Estradiol-only therapy carries no risk for breast cancer, while the breast cancer risk varies according to the type of progestogen. Estradiol therapy combined with medroxyprogesterone, norethisterone and levonorgestrel related to an increased risk of breast cancer, estradiol therapy combined with dydrogesterone and progesterone carries no risk. The breast cancer risk rise progressively by prolonged use, furthermore, comparing to sequential therapy, continuous therapy carries a higher risk.

Longitudinal Relationship Between Psychological Capital and Anxiety in College Students: The Mediating Effect of Emotion Reregulation Strategy and Moderating Effect of Parent-Child Relationship.

Objective: Based on Conservation of resources theory, process model of emotion regulation and attachment theory, the present study examined how psychological capital affects anxiety through the mediation of emotion regulation strategies and explored the moderating role of parent-child relationship. Methods: Using a longitudinal study method, 962 college students were surveyed twice at one-year intervals. Results: (1) College students' emotion regulation strategies (including cognitive reappraisal and expressive suppression) partially mediated psychological capital and anxiety mood; (2) parent-child relationship moderated the pathways of psychological capital and expressive suppression on anxiety, respectively. Conclusion: College students with higher levels of parent-child relationship had stronger predictive effects of psychological capital and weaker predictive effects of expressive suppression on anxiety mood. The research findings clarify the combined effects of emotion regulation and parent-child relationships on anxiety among college students, providing valuable reference for the design and implementation of interventions to promote individual psychological well-being.

The impact of organizational justice on psychological distress among Chinese public hospitals nurses: A cross-sectional study.

Few studies have explored the association between organizational justice and mental health, particularly in collectivist countries. Hence, the aim of the present study was to evaluate the impact of organizational justice on psychological distress and to discuss the findings in collectivist culture. A cross-sectional survey was conducted among nurses from public hospitals in western of China, July 2022, which followed the STROBE guidelines. This study used Chinese versions of the Organizational Justice Scale and Kesseler Psychological Distress Scale to assess the perceptions of organizational justice and mental health levels, respectively. A total of 663 nurses completed the questionnaires. The psychological distress of university-educated and low-income nurses was poor. There was a moderately positive relationship between organizational justice and psychological distress (R = 0.508, P < .01), indicating that the greater level of organizational injustice, the poorer mental health. Hierarchical regression analysis showed that organizational justice was an strong predictor of psychological distress, accounting for approximately 20.5% of the psychological distress. The findings of this study highlight the importance of interpersonal injustice and distributive injustice on psychological distress specific in Chinese culture, suggesting that nursing management or leaders should notice that the most being taken seriously by nurses is their recognition and respect for subordinate, meanwhile, alerting nurses, in some sense, a negative relationship with leaders as a kind of workplace bullying could harm their mental health. The promulgation of organizational justice policy to protect employees from the government and the real role of employee labor union organizations are urgently needed.

Intelligent convolution neural network-assisted SERS to realize highly accurate identification of six pathogenic Vibrio.

Based on label-free SERS technology, the relationship between the Raman signals of pathogenic Vibrio microorganisms and purine metabolites was analyzed in detail. A deep learning CNN model was successfully developed, achieving a high accuracy rate of 99.7% in the identification of six typical pathogenic Vibrio species within 15 minutes, providing a new method for pathogen identification.

Label-free SERS strategy for rapid detection of capsaicin for identification of waste oils.

Identification of waste oils is challenging in the field of food safety due to the lack of common markers and straightforward analytical methods. Herein, we developed a novel label-free surface-enhanced Raman spectroscopy (SERS) strategy to identify waste oils using Ag nanoparticles solution (Ag NPs sol.) as a SERS substrate to significantly enhance the Raman signal of capsaicin marker molecule usually contained in the waste oils. The enhanced signal was directly detected by a portable Raman spectrometer with the limit of detection (LOD) of 2.9 µg L-1 within 10 min. Concentration-dependent SERS investigation showed the linear relationship between the SERS signal intensity of the characteristic peaks and the concentrations of capsaicin in the range of 10-2500 µg L-1 and the correlation coefficient was 0.9895. Our findings show the sensitivity, accessibility, and reliability of this method for the rapid identification of waste oils and furthermore for the practical applications in the field of food safety.

Effect of cotton residues incorporation on soil properties, organic nitrogen fractions, and nitrogen-mineralizing enzyme activity under long-term continuous cotton cropping.

The objective of this experiment was to study the effect of cotton residues incorporation on soil properties, soil organic nitrogen (N) fractions, and N-mineralizing enzyme (protease, and urease) activity in the 0-40 cm soil layer in the long-term continuous cotton field. In this experiment, seven treatments, including cotton residues incorporation for 5, 10, 15 and 20 years (marked as 5a, 10a, 15a, and 20a) and continuous cropping for 5, 10 and 20 years (marked as CK5, CK10 and CK20) were conducted. The results showed that the soil organic carbon (C) and N increased gradually with the increase in the duration of continuous cropping with cotton residues incorporation. Compared with CK20, the 20a treatments reduced the content of amino acid N (AAN), ammonium N (AN), amino sugar N (ASN), hydrolysable unidentified N (HUN), and acid insoluble N (AIN) significantly by 48.6, 32.2, 96.9, 48.3, and 38.7%, respectively (p < 0.05). The activity of protease and urease in 20a treatments significantly increased by 53.4 and 53.1% respectively as compared to CK20 (p < 0.05). Soil organic C and N-mineralizing enzyme activity decreased with the increase in cropping duration in the absence of cotton residues incorporation, while the organic N increased slightly. In conclusion, cotton residues returning can increase the storage of soil organic C and N in long-term continuous cropping cotton field, and improve the soil quality and soil fertility of continuous cropping cotton field.

Unraveling the Critical Role of Melt-Spinning Atmosphere in Enhancing the Thermoelectric Performance of p-Type Bi0.52Sb1.48Te3 Alloys.

Melt spinning has proven effective in maintaining chemical homogeneity and introducing multiscale microstructures that can reduce the lattice thermal conductivity and consequently enhance the thermoelectric performance of consolidated bulk materials. In this work, p-type Bi0.52Sb1.48Te3 bulk alloys are fabricated by melt spinning (MS) followed by subsequent plasma activated sintering (PAS). The influence of different MS atmospheres (air, Ar, N2, and He) on the morphologies of MS ribbons and the thermoelectric properties of MS-PAS bulk materials has been investigated systematically. Because of the relatively high thermal conductivity, a He atmosphere expedites the heat dissipation in the MS process and results in severe sublimation of tellurium and thus inferior thermoelectric performance. In contrast, an Ar atmosphere can essentially prevent heat loss of the fusant and suppress the sublimation of tellurium. Consequently, the corresponding Bi0.52Sb1.48Te3 sample (MS in Ar atmosphere) presents the highest peak ZT and average ZT values of 1.09 (at 340 K) and 0.81 (in 300-500 K), respectively. The average ZT of the sample prepared using an Ar atmosphere is almost three times the one prepared using a He atmosphere. This reflects the importance of using the appropriate atmosphere during the melt-spinning process. This result, which indicates that melt spinning in an Ar atmosphere is preferable to avoid heat loss, can also be extended to other materials.

[Efficacy and metabolic safety of long-term treatment with ethinyl oestradiol/cyproterone and desogestrel/ethinyl oestradiol tablets in women with polycystic ovary syndrome].

OBJECTIVE: To evaluate the efficacy and metabolic safety of long-term treatment with ethinyl oestradiol/cyproteroneand desogestrel/ethinyl oestradiol tablets in women with polycystic ovary syndrome (PCOS). METHODS: Women with PCOSfrom West China Second Hospital of Sichuan University enrolled between September, 2011 and August, 2013 were randomlyallocated to receive either ethinyl oestradiol/cyproterone tablets (Group A, n=355) or desogestrel/ethinyl oestradiol tablets(Group B, n=357) for a prospective observation period of 6 months. Women with insulin resistance also received metformin. Atbaseline, 3 months, and 6 months, the patients were evaluated for menstruation, acne score, body mass index (BMI), waist-tohip ratio (WHR), plasma levels of sex hormones, fasting blood glucose (FPG), HOMA-insulin resistance index (HOMA-IR), serum lipid, ovarian volume, and the number of ovarian follicles. RESULTS: All the patients had a regular menstrual cycle aftertreatments. Testosterone level, acne score, LH/FSH, ovarian volume, and the number of follicles decreased significantly afterthe treatments without significant differences between the two groups. Significant increases were noted in TG, TCh, LDL, HDL, and AIP, and HDL level in group A as compared with group B (P < 0.001). FPG decreased in both groups, and wassignificantly lower in group B at 6 months (P < 0.05). BMI and WHR decreased in all the patients with insulin resistance aftercombination treatment with metformin (P < 0.05), but increased significantly in patients without insulin resistance (P < 0.05). Ingroup A, HOMA- IR significantly increased in patientswithout insulin resistance at 3 months (P < 0.05), whereas asignificant increase was not observed until 6 months ingroup B (P < 0.05). CONCLUSIONS: Both ethinyl oestradiol/cyproterone tablets and desogestrel/ethinyl oestradioltablets can relieve the symptoms of PCOS, but it isadvisable to assess the risk of cardiovascular diseasebefore the treatments.

Bisphenol A Initiates Excessive Premature Activation of Primordial Follicles in Mouse Ovaries via the PTEN Signaling Pathway.

The essence of primary ovarian insufficiency (POI) is the premature exhaustion of primordial follicles in the follicle pool, which is caused by the excessive premature activation of primordial follicles after birth. Bisphenol A (BPA) exposure promotes the transition of primordial follicles to primary follicles, thus the number of primordial follicles in the primordial follicle pool decreases significantly. However, the molecular mechanisms underlying abnormal follicle activation are poorly understood. Phosphatase and tensin homologue (PTEN) signal system is a negative regulator of follicle activation, which is called the brake of follicle activation. Besides, BPA induces Michigan Cancer Foundation-7 breast cancer cells proliferation by dysregulating PTEN/serine/threonine kinase/p53 axis. Whether BPA initiates the excessive premature activation of primordial follicles in the mouse ovaries via PTEN signaling pathway is unclear. In this study, we treated 6-week-old female CD-1 mice with different concentrations of BPA to study the effect of BPA on follicular activation and development in vivo, as well as the role of PTEN signaling in this process. We observed that BPA in concentrations from 1 µg/kg to 10 mg/kg groups downregulated PTEN expression and initiated excessive premature activation of primordial follicles in the mouse ovaries, and this effect was partly reversible by PTEN overexpression. Our results improve the understanding of both the effect of BPA in occurrence of POI and molecular mechanisms underlying initiation of primordial follicle pool activation, thus providing insight for POI treatment and theoretical basis for reducing the risk of POI.

The rostral ventromedial medulla mediates the facilitatory effect of microinjected orphanin FQ in the periaqueductal gray on spinal nociceptive transmission in rats.

Single unit extracellular recordings from spinal dorsal horn neurons were obtained with glass micropipettes in pentobarbital-anesthetized rats. A total of 50 wide dynamic range (WDR) neurons were studied in 25 rats. Microinjection of orphanin FQ (OFQ, 0.1 microg/0.1 microl) (a potent endogenous ligand of the opioid receptor-like receptor (ORL-1)) into the ipsilateral ventrolateral parts of periaqueductal gray (vlPAG) significantly increased C-response and post-discharge activity in most of the WDR neurons. Pre-microinjection of lidocaine (4%) into the nucleus raphe magnus (NRM) (0.5 microl), ipsilateral nucleus reticularis gigantocellularis (NGC) (0.6 microl), or nucleus gigantocellularis pars alpha (NGCalpha) and nucleus reticularis paragigantocellularis lateralis (NPGL) (0.5 microl) markedly reduced intra-vlPAG microinjection of OFQ-induced facilitatory effects on nociceptive responses of WDR neurons. Furthermore, if the NRM and ipsilateral NGC were simultaneously pre-microinjected with lidocaine, the intra-vlPAG microinjection of OFQ-induced facilitation on nociceptive responses of WDR neurons was eliminated. Also, a similar effect was observed when all the NRM, ipsilateral NGC, NGCalpha and NPGL were blocked with lidocaine. No significant effect on nociceptive responses of WDR neurons per se was found after blocking the NRM, ipsilateral NGC, NGCalpha/NPGL, or all the NRM, ipsilateral NGC, and NGCalpha/NPGL with lidocaine. These results indicate that (1) the facilitatory effect evoked by microinjection of OFQ into the vlPAG on nociceptive responses of WDR neurons in the spinal dorsal horn is primarily mediated by the NRM and ipsilateral NGC; (2) the NRM, ipsilateral NGC, and NGCalpha/NPGL do not mediate tonic descending inhibition of the spinal dorsal horn neurons.

Nociceptin/Orphanin FQ in PAG modulates the release of amino acids, serotonin and norepinephrine in the rostral ventromedial medulla and spinal cord in rats.

High density Nociceptin/Orphanin FQ (N/OFQ) and its receptor (NOPr) have been found in the ventrolateral periaqueductal gray (vlPAG), a main output pathway involved in the descending pain-control system. Our previous study demonstrated that the microinjection of N/OFQ into the vlPAG markedly facilitated nociceptive responses of spinal dorsal horn neurons. The aim of the present work was to further provide evidence for the supraspinal mechanisms of action for N/OFQ-mediated nociceptive facilitation by examining the effect of N/OFQ in the vlPAG on neurotransmitter release in the descending pain-control system, including the nucleus raphe magnus (NRM), nucleus reticularis gigantocellularis (NGC) and dorsal horn of the spinal cord. The results showed that the microinjection of N/OFQ into the vlPAG produced robust decreases in 5-hydroxytryptamine (5-HT, serotonin), norepinephrine (NE), and gamma-aminobutyric acid (GABA), and increase in glutamate (Glu) release in the spinal dorsal horn. Spinal application of 5-HT, 2-Me-5-HT (5-HT(3) receptor agonist), muscimol (GABA(A) receptor agonist), and baclofen (GABA(B) receptor agonist) significantly blocked intra-vlPAG-induced facilitation on nociceptive responses. However, the extracellular concentrations of these neurotransmitters in the NRM and NGC exhibited diversity following intra-vlPAG of N/OFQ. In the NRM, intra-vlPAG injection of N/OFQ significantly decreased 5-HT, NE, and Glu, but increased GABA release. Differently, in the NGC, both NE and GABA releases were attenuated by intra-vlPAG of N/OFQ, whereas the concentration of 5-HT and Glu exhibited a trend to increase. These findings provide direct support for the hypothesis that intra-PAG of N/OFQ-induced facilitation of nociceptive responses is associated with the release of 5-HT, NE, and amino acids.