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Instrumented indentation is a versatile method of extracting hyper-elastic material parameters, particularly useful for applications where stress-strain data are difficult to be in-situ measured. Because the analytical force-displacement relation is still unavailable for the indentation of hyper-elastic materials, identifying hyper-elastic parameters often requires an iterative optimization strategy that fits finite element simulations with experimental data. However, the optimization strategy is burdened by heavy computation and its prediction accuracy is greatly influenced by the choice of optimization algorithm. To address these challenges in this study, a bidirectional long short-term memory (BLSTM) neural network is presented that directly predicts hyper-elastic material parameters from indentation load-displacement data, focusing on Mooney-Rivlin hyper-elasticity as an example. To improve the predication accuracy, the condition numbers for the inverse identification of the hyper-elastic parameters are investigated. And, a normalization procedure is proposed to treat the input data, which can guarantee the BLSTM network is well-conditioned. During evaluation, the trained BLSTM network significantly outperforms the iterative optimization strategy using a genetic algorithm. Furthermore, the effect of the normalization procedure is demonstrated. [ABSTRACT FROM AUTHOR]

Objective: To investigate the biomechanical effect of different intervertebral reconstructive heights on adjacent segments following C5/C6 anterior cervical discectomy and fusion (ACDF) through finite element analysis. Methods: A finite element model of intact C4–C7 segments was developed and validated for the present study. Five additional C4–C7 postoperative models were constructed with 100%, 125%, 150%, 175%, and 200% of the benchmark height of C5/C6 on the basis of the intact model. The changes in intradiscal pressure (IDP) and range of motion (ROM) of adjacent segments before and after reconstruction of C5/C6 were analyzed. Results: For the upper adjacent segment (C4/C5), the IDPs under the different loading conditions all increased after reconstruction. The maximum IDPs were 0.387, 0.489, 0.491, and 0.472 MPa under flexion, extension, axial rotation, and lateral bending, respectively, observed at the reconstructive height of 200%. The minimum IDPs were observed at 150% reconstructive height under all loading conditions except extension, and were 57, 86 and 81% of the maximum IDPs under flexion, axial rotation, and lateral bending, respectively. The minimum IDP under extension occurred when the reconstructive height is 125% of the benchmark height. For the lower adjacent segment (C6/C7), the IDPs of postoperative models under all loading conditions also increased compared to the preoperative model. The maximum IDPs after reconstruction under flexion, extension, axial rotation, and lateral bending were 0.402, 0.411, 0.461, and 0.497 MPa, respectively, when the height of the reconstruction was 200% of the benchmark. The minimum IDPs were observed after a reconstruction at 150% of the benchmark, and were 59%, 85%, 82%, and 81% of the maximum IDPs under flexion, extension, axial rotation, and lateral bending loading conditions. Conclusions: The reconstructive height is an important factor affecting the IDP and the ROM of adjacent segments after ACDF. To delay the adjacent segment disease, an intervertebral reconstructive height of 150% is an appropriate height in C5/C6 ACDF. [ABSTRACT FROM AUTHOR]

Objective: To compare the preventive effects of teriparatide and alendronate on the progression of vertebral body collapse in postmenopausal single‐level Kümmell's disease (KD). Methods: From March 2013 to December 2020, the medical records for 53 postmenopausal single‐level KD patients who received conservative treatment with teriparatide (25 patients, teriparatide group) or alendronate (28 patients, alendronate group) were retrospectively reviewed. Midsagittal computed tomography (CT) images were analyzed by ImageJ to assess the intravertebral bone formation (mineralized bone) by calculating the ratio of area of intravertebral mineralized bone (AIMB) to the area of fractured vertebral body (AFVB). The changes in radiological parameters of the fractured vertebral body including kyphosis angle (KA), anterior and posterior border heights (ABH and PBH) and spinal canal diameter (SCD), bone turnover biomarkers (BTMs), and bone mineral density (BMD) were analyzed to evaluate the therapeutic effect. Results: At month 12, the ratio of AIMB to AFVB was significantly greater in teriparatide group (54.28% ± 15.30%) than in alendronate group (35.57% ± 17.61%) (P < 0.001). Sagittal CT substantiated the formation of bone bridge in 16 patients in teriparatide group. No bone bridge was detected in alendronate group. The KA was significantly smaller and the ABH, PBH, and SCD was greater in teriparatide group than in alendronate group (all P < 0.001). The KA increments were significantly smaller in teriparatide group (3.98° ± 1.30°) than in alendronate group (11.43° ± 3.73°) (P < 0.001). The ABH and PBH decrement were significantly lower in teriparatide group (11.96% ± 1.93% and 2.80% ± 2.52%) than in alendronate group (37.04% ± 8.00% and 19.50% ± 8.22%) (both P < 0.001). The BTMs and BMD were significantly greater in the teriparatide group than in the alendronate group. In teriparatide group, KA increment was negatively correlated with the change in PINP (r = −0.781, P < 0.001) and the ratio of AIMB to AFVB (r = −0.592, P = 0.002) from baseline to month 12. The ABH decrement was negatively correlated with the change in PINP (r = −0.612, P = 0.001) and the ratio of AIMB to AFVB (r = −0.806, P < 0.001) from baseline to month 12. Conclusions: In postmenopausal single‐level KD patients, conservative treatment with teriparatide was better than alendronate at preventing the progressive vertebral collapse. [ABSTRACT FROM AUTHOR]

[Display omitted] N -(1,3-dimethylbutyl)- N ′-phenyl- p -phenylenediamine quinone (6PPDQ) has attracted significant attention due to its highly acute lethality to sensitive salmonids. However, studies investigating the mechanisms underlying its acute toxicity have been lacking. In this work, we demonstrated the sensitivity of rainbow trout to 6PPDQ-induced mortality. Moribund trout exhibited significantly higher brain concentrations of 6PPDQ compared to surviving trout. In an in vitro model using human brain microvascular endothelial cells, 6PPDQ can penetrate the blood–brain barrier and enhance blood–brain barrier permeability without compromising cell viability. The time spent in the top of the tank increased with rising 6PPDQ concentrations, as indicated by locomotion behavior tests. Furthermore, 6PPDQ influenced neurotransmitter levels and mRNA expression of neurotransmission-related genes in the brain and exhibited strong binding affinity to target neurotransmission-related proteins using computational simulations. The integrated biomarker response value associated with neurotoxicity showed a positive linear correlation with trout mortality. These findings significantly contribute to filling the knowledge gap between neurological impairments and apical outcomes, including behavioral effects and mortality, induced by 6PPDQ. [ABSTRACT FROM AUTHOR]

Tire wear particles (TWPs) are increasingly being found in the aquatic environment. However, there is limited information available on the environmental consequences of TWP constituents that may be release into water. In this study, TWP leachate samples were obtained by immersing TWPs in ultrapure water. Using high-resolution mass spectrometry and toxicity identification, we identified potentially toxic organic substances in the TWP leachates. Additionally, we investigated their toxicity and underlying mechanisms. Through our established workflow, we structurally identified 13 substances using reference standards. The median effective concentration (EC 50) of TWP leachates on Scenedesmus obliquus growth was comparable to that of simulated TWP leachates prepared with consistent concentrations of the 13 identified substances, indicating their dominance in the toxicity of TWP leachates. Among these substances, cyclic amines (EC 50 : 1.04–3.65 mg/L) were found to be toxic to S. obliquus. We observed significant differential metabolites in TWP leachate-exposed S. obliquus , primarily associated with linoleic acid metabolism and purine metabolism. Oxidative stress was identified as a crucial factor in algal growth inhibition. Our findings shed light on the risk posed by TWP leachable substances to aquatic organisms. [Display omitted] • 81 substances were identified in water leachables of the tire wear particles (TWPs). • Among them, 13 substances were structurally confirmed by reference standards. • S. obliquus was the most susceptible species to TWP leachates. • Identified cyclic amines were highly toxic to S. obliquus. • TWP leachates could trigger oxidative stress and thereby lead to algal cell damage. [ABSTRACT FROM AUTHOR]

Some traditional protection schemes cannot detect a faulted Powerformer when a stator single-line-to-ground fault occurs in parallel Powerformers. A new discrimination method based on kernel principal component analysis (KPCA) and Fisher discrimination analysis considering the distribution characteristics of the data is proposed in this paper. First, the algorithms of the KPCA and the Fisher discrimination are introduced. In order to increase the correct rate of the fault recognition, a kernel function for the distribution characteristics of the data is selected according to the error rate under the historical fault data, which is different from the existing application validation methods. Then, the detected data in the system model are processed to detect whether a stator single-line-to-ground fault occurred in the Powerformer using the KPCA and the Fisher discrimination analysis based on an optimal kernel function. Finally, simulation results show that the proposed scheme can exactly detect the fault for a Powerformer in different neutral grounding systems when a stator single-line-to-ground fault occurred. [ABSTRACT FROM AUTHOR]

Background: CellDetect® staining technique is a newly invented technique for cancer diagnosis. It easily distinguishes between normal and neoplastic cells including pre-cancer and squamous cell carcinoma (SCC) cells, based on staining color and morphology. In this study, application of CellDetect® staining technique was assessed in diagnosis of human cervical cancer as compared with hematoxylin and eosin (H&E) staining in conventional slides and Thinprep cytologic test (TCT) smears. Methods: The conventional slides and TCT smears of 600 patients were stained and observed while comparing with H&E staining to assess sensitivity and specificity of CellDetect® staining technique in diagnosis of cervical cancer. Conventional smear slides (440 cases) were fixed in 95% ethanol or with CYTOFIX® Spray. TCT smears (160 cases) were processed based on manual. The paraffin sections from cervical intraepithelium neoplasia (CIN) 2–3 and SCC cases were prepared by biopsy. Results: CellDetect® staining exhibited well cell morphology, simultaneously, showed dual color discrimination, the stain targeted cytoplasm in normal cells in green and dysplastic cells or neoplastic cells in purple/red. Both cervical cell smears or both fixation methods in conventional slides did not affect CellDetect® staining diagnosis, especially in tissue biopsies CellDetect® staining exhibited well epithelium layers to benefit the diagnosis of CIN grade. The sensitivity and specificity of CellDetect® staining technology in diagnosing CIN and SCC were 94.34% and 88.73%, respectively. Conclusions: CellDetect® staining technique provided a dual color discrimination and morphological analysis. It has the potential to become one of the most effective methods for cervical screening and early diagnosis. [ABSTRACT FROM AUTHOR]

Background: Recent studies have demonstrated that synthetic dsRNAs may produce therapeutic effects in a target-independent manner through stimulation of the toll-like receptor-3 (TLR3)/interferon pathway; as a result, angiogenesis and proliferation of tumor cells are inhibited. Thus, this pathway may become a potential target of dsRNA in tumor suppression. In this study, we evaluated the role of synthetic dsRNA as a TLR3 synergist and by combining with sorafenib in anti-hepatocellular carcinoma (HCC) in vitro and in vivo.Methods: Four dsRNAs were designed and synthesized. One of them that was capable of activating TLR3 most effectively in human HCC cell line (HepG2.2.15) was selected as a TLR3 synergist (called BM-06). Subsequently, the expression of proteins relating to TLR3 signaling pathway, such as NF-κB, caspase 8 survivin, bcl-2 and PCNA affected by BM-06, sorafenib alone or in combination, was compared. The migration, proliferation and apoptosis of HepG2.2.15 cells were evaluated in presence of BM-06, sorafenib alone or in combination of both. The similar treatments were also applied in an SD rat primary HCC model.Results: qRT-PCR data showed that the expression of TLR3 and NF-κB in HepG2.2.15 cells was enhanced. BM-06 was selected as a TLR3 synergist capable of activating the TLR3/interferon pathway most effective among 4 synthetic dsRNAs. The migration and proliferation were significantly inhibited in treated HepG2.2.15 cells with BM-06 or Sorafenib alone as compared with PBS-sham control (P<0.01). However, the role of combination BM-06 with Sorafenib was the most prominent. Tumor cell apoptotic rate was increased by BM-06 or combination when compared to PBS or poly(I:C) (P<0.05). Similarly, in orthotopic HCC SD rats, the effect of the combination was superior to either agent alone on the inhibition of tumor growth and induction of HCC cell apoptosis (P<0.05).Conclusions: dsRNA alone was capable of inhibiting the proliferation of HepG2.2.15 cells and tumor growth of orthotopic HCC SD rats, but the effect of combination of dsRNA with sorafenib was more prominent. These findings implicate the potential role of combined use of a dsRNA, a TLR3 synergist, and sorafenib in inhibition of HCC. [ABSTRACT FROM AUTHOR]

Two new dammarane triterpene glycosides named notoginsenosides Rw 1 (1) and Rw 2 (2) were isolated from the rhizomes of Panax notoginseng, together with 20 known compounds including protopanaxadiol (3), protopanaxatriol (4), ginsenosides Rb1 (5), Rd (6), Re (7), Rg1 (8), Rg2 (9), 20-(S)-Rg3 (10), 20-(R)-Rg3 (11), Rh1 (12), Rh4 (13), Rf (14), 20-O-glucopyranosyl Rf (15), notoginsenosides R1 (16), R2 (17), T5 (18), S (19), T (20), and Fa (21), and koryoginsenoside R1 (22). Based on FABMS, HRFABMS, IR, 1H, 13C, and 2D-NMR (HSQC, HMBC, and COSY) spectral data, the structures of the new compounds were elucidated as 6-O-β-d-xylopyranosyl-20-O-β-d-xylopyranosyl-(1 → 6)-β-d-glucopyranosyldammar-24-ene-3β,6α,12β,20(S)tetraol (1) and 6-O-β-d-xylopyranosyl-(1 → 2)-β-d-glucopyranosyldammar-22-ene-(trans)-3β,6α,12β,20(S), 25-pentaol (2). Compounds 3, 4, 13, and 22 were isolated from P. notoginseng for the first time. [ABSTRACT FROM AUTHOR]

Background: A role for autophagy, a conserved cellular response to stress, has recently been demonstrated in human cancers. Aberrant expression of Beclin-1, an important autophagic gene, has been reported in various human cancers. In the present study, we investigated the significance and relationship between Beclin-1 expression and cell proliferation, apoptosis, microvessel density (MVD) and clinical pathological changes or prognosis in human hepatocellular carcinoma (HCC).Methods: A total of 103 primary HCC patients were involved in the study. Expression of Beclin-1, PCNA, NET-1, Bcl-2, Bax, Survivin in cancer cells and CD34 in stromal microvessels were evaluated immunohistochemically in tissue microarrays comprising 103 cases of HCC and 57 matched adjacent nontumor liver tissues. Correlations between clinicopathological characteristics and survival of HCC patients were explored.Results: The positive rate of Beclin-1 was significantly lower in HCC tissues than adjacent tissues (72.8 vs. 89.5%, χ2 = 6.085, P = 0.015). In HCC, Beclin-1 expression was negatively correlated with cirrhosis background (r = -0.216, P = 0.029), Edmondson grade (r = -0.249, P = 0.011), vascular invasion (r = -0.246, P = 0.012), PCNA (r = -0.242, P = 0.014), NET-1 (r = -0.245, P = 0.013), anti-apoptosis protein Bcl-2 (r = -0.245, P = 0.013) and MVD (r = -0.292, P = 0.003), and positively correlated with pro-apoptosis protein Bax (r = 0.242, P = 0.014).Significant differences in the 5-year survival rates were seen among patients with Beclin-1 strong positive (++) (59.1%, 13/22), moderate positive (+) (28.3%, 15/53) and weak negative expression (-) (14.6%, 7/28) (P = 0.043). Significant differences were detected between Beclin-1 (++) and either Beclin-1 (+) (P = 0.036) or Beclin-1 (-) groups (P = 0.008), but no significant difference between Beclin-1 (+) and Beclin-1 (-) groups (P = 0.281) was observed.Survival rates were positively related to high Beclin-1 co-expressed with low PCNA, NET-1, or Bcl-2, lower MVD, and high Bax. Univariate and multivariate Cox regression analysis revealed that Beclin-1 expression was an independent indicator for overall survival in HCC patients (P < 0.05).Conclusions: The pathogenesis and progression of HCC are associated with reduced autophagy. The expression of Beclin-1 and Bax in HCC tissues may provide a synergistic effect towards inhibiting HCC proliferation, infiltration, metastasis and angiogenesis. Beclin-1 expression may be a valuable prognostic marker of HCC. [ABSTRACT FROM AUTHOR]