SEPHS1 attenuates intervertebral disc degeneration by delaying nucleus pulposus cell senescence through the Hippo-Yap/Taz pathway.

Nucleus pulposus cell (NPC) senescence is a major cause of intervertebral disc degeneration (IVDD). Oxidative stress and reactive oxygen species (ROS) play critical roles in regulating cell senescence. Selenophosphate synthetase 1 (SEPHS1) was reported to play an important role in mitigating oxidative stress in an osteoarthritis (OA) model by reducing the production of ROS, thereby, delaying the occurrence and development of osteoarthritis. In this study, we explored the, hitherto unknown, role of SEPHS1 in IVDD in vitro and in vivo using an interleukin-1ß (IL-1ß)-induced NPC senescence model and a rat needle puncture IVDD model, respectively. SEPHS1 delayed NPC senescence in vitro by reducing ROS production. Age-related dysfunction was also ameliorated by the overexpression of SEPHS1 and inhibition of the Hippo-Yap/Taz signaling pathway. In vivo experiments revealed that the overexpression of SEPHS1 and inhibition of Hippo-Yap/Taz alleviated IVDD in rats. Moreover, a selenium (Se)-deficient diet and lack of SEPHS1 synergistically aggravated IVDD progression. Taken together, our results demonstrate that SEPHS1 plays a significant role in NPC senescence. Overexpression of SEPHS1 and inhibition of Hippo-Yap/Taz can delay NPC senescence, restore the balance of extracellular matrix metabolism, and attenuate IVDD. SEPHS1 could be a promising therapeutic target for IVDD.NEW & NOTEWORTHY Selenophosphate synthetase 1 (SEPHS1) deficiency leads to an increase in reactive oxygen species levels and in the subsequent activation of the Hippo-Yap/Taz signaling pathway. In the rat model of intervertebral disc degeneration (IVDD), overexpression of SEPHS1 and inhibition of Hippo-YAP/Taz mitigated the progression of disc degeneration indicating the involvement of SEPHS1 in IVDD. SEPHS1 is a promising therapeutic target for IVDD.

Dehydrative Alkylation of Phenols with Alcohols via Formation of Triflate.

An efficient synergistic trityl cation ([Ph3C][B(C6F5)4])/triflic anhydride (Tf2O) catalyzed alkylation of phenols with alcohols is reported. Benefiting from the formation of the triflate in situ, cheap and readily available active alcohols can be used as the alkylating reagents, and the reaction proceeds under mild reaction conditions with a broad substrate scope. This protocol enables the synthesis of ortho-selective phenols and 2,4,6-trisubstitued phenols containing three different alkyl groups. tert-Amyl triflate was synthesized, and mechanistic studies support a triflate-mediated alkylation process.

The value of histopathologic examination and Xpert (MTB/RIF) assay in diagnosis of cervical lymph node tuberculosis after coarse needle biopsy guided by CEUS: a retrospective analysis of 612 cases.

OBJECTIVE: To investigate the value of histopathological examination (HPE) and Xpert Mycobacterium tuberculosis bacilli/rifampicin (MTB/RIF) assay in diagnosis of cervical lymph node tuberculosis (LN TB) after coarse needle biopsy (CNB). METHODS: We retrospectively analyzed 612 samples obtained from October 2017 to August 2023 from patients suspected cervical LN TB with surgically pathological, microbial culture confirmed, and clinically confirmed cervical lymph node enlargement who received ultrasound-guided CNB assisted by contrast-enhanced ultrasound (CEUS) at our hospital. All specimens were assessed by HPE and the Xpert (MTB/RIF) assay. We analyzed the results to determine the diagnostic value of HPE and Xpert (MTB/RIF) assay in samples taken after CEUS-assisted CNB of LN TB, and to evaluate the safety of CNB. RESULTS: Based on the comprehensive reference standard established in this study, 532 of 612 patients were diagnosed with cervical LN TB, of which 476 were CNB positive cases, the positive rate of diagnosis was 89.5%。The sensitivity, specificity, positive predictive value, negative and predictive value of HPE were 80.4%, 91.2%, 98.4%, 41.2% respectively, while those of the Xpert MTB/RIF assay were 75.7%, 98.7%, 99.7%, 38.0% respectively. No postoperative complications were noted, and the Clavien-Dindo grade was 2. CONCLUSION: CEUS-assisted CNB has high diagnostic value and is safe for cervical LN TB. The sensitivity of HPE is slightly higher than that of Xpert (MTB/RIF) assay, and the specificity of Xpert (MTB/RIF) assay is higher than that of HPE, so Xpert (MTB/RIF) assay can correct the cervical lymph node tuberculosis with negative HPE.

Application of contrast-enhanced ultrasound in the diagnosis of tuberous vas deferens tuberculosis.

BACKGROUND: To assess the value of contrast-enhanced ultrasound (CEUS) in the diagnosis of tuberous vas deferens tuberculosis (VD TB) and improve the positive diagnostic rate of VD TB. METHODS: CEUS and routine ultrasound (US) images of 17 patients with tuberous VD TB confirmed by surgery, pathology, or laboratory semen examination were retrospectively analyzed and summarized, and the positive rates of both imaging techniques were compared. RESULTS: The 19 VD lesions of the 17 patients were divided into two types according to the CEUS findings: Type I and Type II, and type II was divided into Types IIa, IIb, and IIc. Of the nodules with transverse diameters > 1 cm, 100% presented as type II. Of the nodules with transverse diameters < 1 cm, 37.5% (3/8) presented as type I and 62.5% (5/8) presented as type II. The sonographic manifestations of tuberous VD TB were hypoechoic and mixed echoic. The positive diagnostic rate was 89.5% for CEUS and 68.4% for US, but the difference was not significant (χ2 = 2.533; P = 0.111). CONCLUSIONS: CEUS was able to show the blood supply characteristics of tuberous VD TB, the internal necrosis of nodules was more easily observed by CEUS than by routine US, which is helpful for the diagnosis of tuberous VD TB.

Application of ultrasound multimodal imaging in the prediction of cervical tuberculous lymphadenitis rupture.

Lymph node tuberculosis is particularly common in regions with a high tuberculosis burden, and it has a great risk of rupture. This study aims to investigate the utility of ultrasound multimodal imaging in predicting the rupture of cervical tuberculous lymphadenitis (CTL). 128 patients with unruptured CTL confirmed by pathology or laboratory tests were included. Various ultrasonic image features, including long-to-short-axis ratio (L/S), margin, internal echotexture, coarse calcification, Color Doppler Flow Imaging (CDFI), perinodal echogenicity, elastography score, and non-enhanced area proportion in contrast-enhanced ultrasound (CEUS), were analyzed to determine their predictive value for CTL rupture within a one-year follow-up period. As a result, L/S (P < 0.001), margin (P < 0.001), internal echotexture (P < 0.001), coarse calcification (P < 0.001), perinodal echogenicity (P < 0.001), and the area of non-enhancement in CEUS (P < 0.001) were identified as significant imaging features for predicting CTL rupture. The prognostic prediction showed a sensitivity of 89.29%, specificity of 100%, accuracy of 95.31%, respectively. Imaging findings such as L/S < 2, unclear margin, heterogeneous internal echotexture, perinodal echogenicity changed, and non-enhancement area in CEUS > 1/2, are indicative of CTL rupture, while coarse calcification in the lymph nodes is associated with a favorable prognosis.

The role of genetic factors in pediatric myelodysplastic syndromes with different outcomes.

BACKGROUND: Pediatric myelodysplastic syndromes (MDS) are rare disorders with an unrevealed pathogenesis. Our aim is to explore the role of genetic factors in the pathogenesis of MDS in children with different outcomes and to discover the correlation between genetic features and clinical outcomes as well as disease characteristics. METHODS: We conducted an analysis of archived genetic data from 26 patients diagnosed with pediatric MDS at our institution between 2015 and 2021, examining the association between different genetic characteristics and clinical manifestations as well as prognosis. Additionally, We presented three cases with distinct genetic background and outcomes as examples to elaborate the role of genetic factors in pediatric MDS with different prognoses. RESULTS: Genetic variations were detected in 13 out of the 26 patients, including 8 patients with co-occurrence of somatic and germline mutations (CSGMs) and 5 patients with somatic mutations alone. Our analysis revealed that advanced MDS (4/8, 50% vs. 1/5, 20% and 4/11, 36.4%), PD (3/8, 37.5% vs. 1/5, 20% and 1/11 9.1%), and TD (6/8, 75% vs. 2/5, 40% and 2/11, 18.2%) were more common in patients with CSGMs than those with somatic mutations alone or without any mutations. We also found out in our study that 8 patients with CSGMs had evidently different clinical outcomes, and we presented 3 of them as examples for elaboration. Case 1 with germline and somatic mutations of unknown significance had a relatively slow disease course and a good prognosis. Case 2 with compound heterozygous germline SBDS variants and somatic mutations like del20q had a stable disease course and a reversed outcome. Case 3 with a germline GATA2 variant and somatic mutations including - 7 had a rapidly progressive disease course and a worst prognosis. CONCLUSION: Our findings indicate that genetic background of pediatric MDS is closely linked with disease characteristics as well as outcomes and that CSGMs may lead to disease progression. It should be emphasized that the interaction between certain germline variants and somatic mutations, such as SBDS and del20q, may result in hematopoietic stem cell adaptation (improved hematopoiesis) and reversed clinical outcomes, which can facilitate the development of targeted therapy.

Ionic liquid-assisted synthesis of In2O3 nanoparticles for ppb-level NO2 sensing at low temperature.

Highly sensitive detection of nitric dioxide (NO2) has recently attracted much attention due to its harmful to the human health even at a low concentration of 0.1 parts per million (ppm). Herein, In2O3 nanoparticles (NPs) were prepared via a facile ionic liquid (IL) assisted solvothermal method with subsequent calcination and then were analyzed through the characterization of X-ray diffractometer (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and nitrogen adsorption-desorption techniques. Morphological characterization demonstrated that the resultant compounds were In2O3 NPs with a diameter ranging from 20 to 30 nm. The gas sensor based on the In2O3 NPs prepared with IL exhibited excellent NO2-sensing properties in terms of fast response/recovery speed (26.6/10.0 s), high response (310.0), good repeatability and long-term stability to 10 ppm NO2 gas at low working temperature of 92 °C. The gas-sensing mechanism of In2O3 NPs to NO2 was represented to the surface adsorption control model and the possibilities relating to the improved NO2 sensing performance of the In2O3 NPs synthesized with IL-assisted were also discussed in detail.

Chemical Cyclic Amplification: Hydroxylamine Boosts the Fenton Reaction for Versatile and Scalable Biosensing.

Nucleic acid detection is undoubtedly one of the most important research fields to meet the medical needs of genetic disease diagnosis, cancer treatment, and infectious disease prevention. However, the practical detection methods based on biological amplification are complex and time-consuming and require highly trained operators. Herein, we report a simple, rapid, and sensitive method for the nucleic acid assay by fluorescence or naked eye using chemical cyclic amplification. The addition of hydroxylamine (HA) during the Fenton reaction can continuously generate hydroxyl radicals (•OH) via Fe3+/Fe2+ cycle, termed as "hydroxylamine boosts the Fenton reaction (Fenton-HA system)". Meanwhile, the reducing substances, such as terephthalic acid or o-phenylenediamine, react with •OH to generate oxidized substances that can be recognized by the naked eye or detected by fluorescence so as to realize the detection of Fe3+. The concentration of Fe3+ has a good linear relationship with fluorescence intensity in the range of 0.1 to 100 nM, and the limit of detection is calculated to be 0.03 nM (S/N = 3). Subsequently, Fe was introduced into the nucleic acid hybridization system after the Fe source was transformed into Fe3+, and the nucleic acids were indirectly determined by this method. This Fenton-HA system was used for sensing HIV-DNA and miRNA-21 to verify the validity of this method in nucleic acid detection. The detection limits were as low as 2.5 pM for HIV-DNA and 3 pM for miRNA-21. We believe that our work has unlocked an efficient signal amplification strategy, which is expected to develop a new generation of highly sensitive chemical biosensors.

Optical performance evaluation of an infrared system of a hypersonic vehicle in an aero-thermal environment.

At hypersonic velocities, the turbulent flow field generated by an aircraft, along with its temperature distribution, leads to significant aerodynamic optical effects that severely impede the performance of internal optical systems. This study proposes a method for analyzing the temporal characteristics of imaging degradation in a detector window infrared imaging system under different field angles of hypersonic velocity. Based on heat transfer theory, a method for solving the transient temperature field in the optical window of a high-speed aircraft is derived and established, considering unsteady thermal conduction-radiation coupling. Additionally, an optical window radiation tracing method is introduced, which directly determines the initial direction vector of light reaching the detector. This method reduces the workload of radiation transmission, significantly enhancing the efficiency of radiation calculations. The time characteristics of image degradation caused by aero-optical effects in high-speed aircraft are analyzed using metrics such as peak signal-to-noise ratio, wave aberration, and point diffusion function. The results demonstrate that as working time increases and the viewing angle widens, the impact of aero-optics on the aircraft imaging system becomes more severe. Moreover, compared to the aerodynamic light transmission effect, the aerodynamic thermal radiation effect has a more detrimental influence on imaging quality.

Adaptive optimization technology of a conformal infrared dome based on the Von Karman surface under hypersonic conditions.

With the advent of the hypersonic era, diverse combat methods of hypersonic precision-guided weapons have been gradually developed. This study focuses on the precise design of a conformal infrared dome to accommodate different working conditions. To achieve this, an adaptive optimization technology for configuring conformal infrared domes is proposed, employing a multi-objective genetic algorithm. The technology enables the dome to dynamically balance its aerodynamic and imaging performance, taking into account the specific characteristics of each working condition. Moreover, it streamlines the design process of the conformal infrared domes. By optimizing the design with von Karman surfaces, we can overcome the limitations associated with the traditional quadric configuration. In order to evaluate its performance, a comparison was made with a conventional ellipsoid dome. The results indicate that, under the same working conditions, the air drag coefficient of the optimized infrared dome is reduced by 34.29% and that the peak signal-to-noise ratio of the distorted image from the infrared detection system is increased by 1.7%. We have demonstrated the effectiveness of the optimization method to balance aerodynamic performance and optical performance. Hopefully, our new method will improve the comprehensive performance of the infrared dome as well as the guidance capability of infrared detection technology.

Integration of N, P-doped carbon quantum dots with hydrogel as a solid-phase fluorescent probe for adsorption and detection of Fe3.

In this work, a novel nitrogen-phosphorus co-doped carbon quantum dots (N, P-CQDs) hydrogel was developed utilizing the as-synthesized N, P-CQDs and acrylamide (AM) with the existence of ammonium persulfate and N, N'-methylene bisacrylamide (N-MBA). In consistent with pure N, P-CQDs, the N, P-CQDs hydrogel also shows a dramatic fluorescence property with maximum emission wavelength of 440 nm, which can also be quenched after adsorbing iron ions (Fe3+). When the concentration of Fe3+is 0-6 mmol l-1, a better linear relationship between Fe3+concentration and the fluorescence intensities can be easily obtained. Additionally, the N, P-CQDs hydrogel exhibits better recyclability. This confirms that the N, P-CQDs hydrogel can be used for adsorbing and detecting Fe3+in aqueous with on-off-on mode. The fluorescence quenching mainly involves three procedures including the adsorption of Fe3+by hydrogel, integration of Fe3+with N, P-CQDs and the transportation of conjugate electrons in N, P-CQDs to the vacant orbits of Fe3+and the adsorption process follows a pseudo-second-order kinetic model confirmed in the Freundlich isotherm model. In conclusion, this work provides a novel route for synchronously removing and detecting the metal ions in aqueous by integrating N, P-CQDs with hydrogel with better recyclability.

Value of contrast-enhanced ultrasound in the differential diagnosis of ureteral tuberculosis from ureteral malignant tumour in women.

This study aimed to evaluate the contrast-enhanced ultrasound (CEUS) features of ureteral tuberculosis (UTB) and ureteral malignant tumour and to explore its application value in the differentiation of UTB from ureteral tumour. The ultrasound (US) and CEUS imaging features of 33 and 12 cases of pathologically confirmed UTB and ureteral malignant tumour, respectively, were retrospectively evaluated, and echo of the ureteral wall, abnormal echo of the lumen, degree of ureteral dilation and CEUS patterns of the two diseases were statistically analysed. The results revealed that the lumen echo of UTB was hyperechoic or anechoic, whereas that of ureteral tumour lesions was hypoechoic (χ2 = 28.22, P < 0.001). The wall echo of the obstruction site differed between the two diseases; in UTB, the ureteral wall was thickened but the outer wall remained intact, whereas in ureteral tumour, both the malignant tumour wall and outer wall were irregular (χ2 = 30.25, P < 0.001). CEUS of UTB revealed nonenhancement or heterogeneous enhancement in the lumen, whereas that of ureteral tumours revealed significant homogeneous enhancement (χ2 = 30.25, P < 0.001). Thus, CEUS can reveal lesion microcirculation and be used to evaluate blood supply characteristics in the lesion, indicating that it has high potential for differentiating the two diseases.

A combination of fluorine-induced effect and co-sensitization for highly efficient and stable dye-sensitized solar cells.

Developing dyes with high open-circuit photovoltage (Voc) is a vital strategy to improve the power conversion efficiency (PCE) of co-sensitized solar cells (co-DSSCs). Herein, three organic fluorine-containing dyes [YY-ThP(3F), YY-ThP(2F), and YY-ThP(26F)] are designed and synthesized for investigating the fluorine-induced effect on photophysical and photovoltaic performances. Consequently, this effect can significantly broaden the UV-vis absorption spectra of dyes but fail to improve the light-harvesting capability of DSSCs. Strikingly, YY-ThP(3F), featuring 3-position fluorine substitution to cyanoacrylic acid, yields a relatively high Voc compared to the corresponding fluorine-free dye (YY-ThP). Furthermore, the co-sensitization of YY-ThP+YY-ThP(3F) achieves a remarkably high PCE and long-term stability. This work implies that the combination of judicious molecular engineering and co-sensitization is a promising strategy for highly efficient and stable DSSCs.

Analysis of bleeding after ultrasound-guided needle biopsy of benign cervical lymph nodes.

AIM: Summarized the incidence of bleeding after ultrasound-guided coarse needle biopsy (US-CNB) of benign cervical lymph nodes. METHODS: We retrospectively examined the clinical and follow-up records of 590 patients with benign cervical lymph node disease who underwent US-CNB at our hospital during February 2015-July 2022 and were confirmed to have the disease by CNB and surgical pathology. The number of cases, types of diseases, and degree of bleeding of all patients with bleeding after US-CNB were statistically analyzed. RESULTS: Of the 590 patients, bleeding was noted in 44 cases(7.46%), and the infectious lymph node bleeding rate was 9.48%. Infectious lymph nodes were more likely to bleed than noninfectious lymph nodes after CNB, ,x2 = 8.771; P = 0.003, Lymph nodes with pus were more likely to bleed than solid lymph nodes after CNB, x2 = 4.414; P = 0.036,. CONCLUSION: The bleeding of all patients after CNB was minor bleeding. Infected lymph nodes bleed more frequently than noninfected lymph nodes. Lymph nodes with mobility and a large pus cavity, are more likely to bleed after CNB.

Stress Monitoring of Segment Structure during the Construction of the Small-Diameter Shield Tunnel.

Segmental stress during the construction process plays a pivotal role in assessing the safety and quality of shield tunnels. Fiber Bragg grating (FBG) sensing technology has been proposed for tunnel segment stress monitoring. A laboratory test was conducted to validate the reliable strain measurement of FBG sensors. The field in situ monitoring of a sewerage shield tunnel was carried out to examine the longitudinal and circumferential stresses experienced by the segments throughout the construction phase. The cyclic fluctuations in stress were found to be synchronized with the variations in shield thrust. A comparison was made between the longitudinal and circumferential stress variations observed during the shield-driving and segment-assembly processes. Additionally, the time required for the grouting to reach its full curing strength was estimated, revealing its impact on the stress levels and range of the pipe segment. The findings of this study offer an enhanced understanding of the stress state and health condition of small-diameter shield tunnels, which can help in optimizing the design and construction process of tunnel segments, as well.

Spatial Responses of Ecosystem Service Trade-offs and Synergies to Impact Factors in Liaoning Province.

Global ecosystem services (ESs) are experiencing a significant decline, necessitating the development of robust environmental governance policies. To address the lack of integrated planning with heavy industry as the research object and a lack of knowledge of ES trade-offs and synergies in China's ecological and environmental governance. In this study, the spatial and temporal variations of four ESs (water yield (WY), soil conservation (SC), carbon storage (CS), and habitat quality (HQ)) were determined in the study area of Liaoning Province. Explore the mechanisms that shape ecosystem service trade-offs and synergies and the factors that influence them. Spearman's correlation and difference analyses were proposed to determine the spatial and temporal distributions of trade-offs and synergistic relationships among ESs. In addition, we constructed a multiscale geo-weighted regression (MGWR) model to investigate driver spatial heterogeneity affecting trade-offs and synergies. The results revealed that (1) In the study area, ESs were on the rise in Liaoning Province. (2) Temporally, ESs were overwhelmingly dominated by synergies; at the spatial scale, ESs were dominated by trade-offs of varying degrees, with the area of synergy between WY and SC being the highest. (3) ESs demonstrated spatial heterogeneity in intensity and were more impacted by natural factors such as vegetation cover, elevation, and precipitation than by characteristics related to human activity. This study helps improve understanding of the interactions and dependencies among ESs and can provide a reference for ecological governance and improvements in Liaoning Province.

Multiple Self-Supervised Auxiliary Tasks for Target-Driven Visual Navigation Using Deep Reinforcement Learning.

Visual navigation based on deep reinforcement learning requires a large amount of interaction with the environment, and due to the reward sparsity, it requires a large amount of training time and computational resources. In this paper, we focus on sample efficiency and navigation performance and propose a framework for visual navigation based on multiple self-supervised auxiliary tasks. Specifically, we present an LSTM-based dynamics model and an attention-based image-reconstruction model as auxiliary tasks. These self-supervised auxiliary tasks enable agents to learn navigation strategies directly from the original high-dimensional images without relying on ResNet features by constructing latent representation learning. Experimental results show that without manually designed features and prior demonstrations, our method significantly improves the training efficiency and outperforms the baseline algorithms on the simulator and real-world image datasets.

Diagnostic value of contrast-enhanced ultrasound combined with MRI for cervical hyperplastic, tuberculosis-infected, and metastatic lymph nodes.

Objective: To explore the diagnostic value of contrast-enhanced ultrasound (CEUS) combined with magnetic resonance imaging (MRI) for cervical abnormal lymph nodes. Methods: We retrospectively reviewed the clinical records of 150 patients undergoing lymph node examinations at Hangzhou Chest Hospital from January 2017 to December 2019. According to the characteristics of lymph nodes, the patients were divided into three groups: 45 patients had hyperplastic lymph nodes (HLNs; Group-A), 55 had lymph node tuberculosis (LNTB; Group-B), 50 had metastatic lymph nodes (MLN; Group-C). We compared the ultrasonic examination and MRI results between the groups, and compared the diagnostic value of CEUS alone and CEUS plus MRI. Results: Lower resistance indexes (RI) for Groups-A and B than Group-C(P<0.05). Mixed blood flow type was predominant in Group-A, while the lymphohilum type was predominant in Group-B, and the marginal type was predominant in Group-C(P<0.05). The proportion of non-uniform types in Group-B was significantly higher than that in Groups-A and C(P<0.05). After enhancement, the proportions of non-uniform types in Groups-A and B were higher than Group-C(P<0.05). The results of MRI examination showed that positive reinforcement integral (PEI) and maximum slope of increase (MSI) values increased sequentially from Group-B to Group-A, and then to Group-C(P<0.05); while time to peak (TTP) values increased sequentially from Group-C to Group-A, and then to Group-B(P<0.05). The diagnosis accuracy of CEUS combined with MRI was significantly higher than that of CEUS alone(P<0.05). RI-PEI, RI-MSI, and RI-TTP showed high specificity and sensitivity in the diagnosis and differentiation of HLNs, LNTB, and MLNs(P<0.05). Conclusion: CEUS combined with MRI can significantly facilitate the differential diagnosis between HLNs, LNTB, and MLNs. The two diagnosis methods combined improve the diagnosis accuracy of cervical lymph node diseases.

Rac1 regulates nucleus pulposus cell degeneration by activating the Wnt/ß-catenin signaling pathway and promotes the progression of intervertebral disc degeneration.

Nucleus pulposus cell (NPC) dysfunction is considered as an important event related to intervertebral disc degeneration (IVDD). In the present study, tandem mass spectrometry (TMT) was used to detect total protein expression of nucleus pulposus (NP) in patients with IVDD and healthy controls. Bioinformatic analysis was performed to identify differentially expressed proteins that may be involved in the degeneration of NP. The results show that Rac1 may be a key protein involved in the degeneration of NP via Wnt/ß-catenin pathway activation. We investigated the influence of Rac1 on IVDD degeneration and associated mechanisms. Rac1 expression increased in interleukin (IL)-1ß-stimulated human NPCs, consistent with the results of TMT. The Rac1 inhibitor NSC23766 alleviated the degeneration of NPCs in vitro. Furthermore, Rac1 activated Wnt/ß-catenin signaling, and the inhibition of this pathway significantly ameliorated the Rac1-mediated degenerative phenotype. NSC23766 exerted protective effects on IVDD in a puncture rat model. Taken together, these data suggest that Rac1 inhibition can delay NPC degeneration, probably through the regulation of the Wnt/ß-catenin pathway. This study has the potential to advance understanding of the mechanism of occurrence of degenerative NP tissues and to provide novel strategies for slowing IVDD progression.

Maize starch derived boron doped carbon spheres via facile solvothermal route as the photoluminescence sensor for determination of pH and Cr(VI).

In this work, a kind of boron doped carbon spheres (B-CSs) was successfully synthesized utilizing maize starch as carbon source and boric acid as dopant via facile solvothermal method. The chemical structure of the prepared B-CSs was systemically investigated by TEM, FT-IR, XRD, XPS and EDS. The synthesized B-CSs feature spherical structure with average size of ∼254 nm and exhibit strong photoluminescence (PL) with maximum emission at a wavelength of ∼453 nm under irradiation at 350 nm, leading to a quantum yield of 6.2%. Furthermore, the aqueous pH and Cr(VI) has a significantly various impact on the PL intensity of B-CSs, which can be flexibly utilized as the PL sensor for detection aqueous pH and Cr(VI) in aqueous. Particularly, the B-CSs have a desirable sensitivity and selectivity for detection of Cr(VI) with a low detection limit of ∼0.34µmol l-1. Conclusively, our work provides a novel and dual-functional fluorescent sensor for detection of the pH and toxic metal ions in water environment.