Predicting root fracture after root canal treatment and crown installation using deep learning.

Background/purpose: Vertical root fracture (VRF) is a prevalent reason for tooth extraction following root canal treatment and even after crown placement. Predicting fractures is challenging due to multifactorial nature. The current study aimed to predict the likelihood of fracture following root canal treatment and crown placement by developing a deep learning (DL) model. Materials and methods: DL techniques were employed to analyze a dataset comprising 145 clinical cases consisting of 97 fractured teeth and 48 non-fractured teeth. This dataset spanned a five-year period and encompassed cases involving root canal therapy and crown installation. The analysis identified several root fracture-related parameters, which were incorporated into the DL system. The dataset consisted of 17 features presented in a mixed-type tabular format. Results: The deep neural network (DNN) model surpassed the support vector machine (SVM) model with a higher accuracy (80.7 % vs. 71.7 %) and F1-score value (0.857 vs. 0.817) for predicting root fracture. Furthermore, in determining root fracture occurrence, it was observed that 17 significant characteristics in the DNN model outperformed the 7 features by 11.7 % in accuracy and 10 % in F1-score. Conclusion: DL shows promise in predicting root fracture post root canal therapy and prosthesis, and it may have the potential to aid clinicians in assessing fracture risk and improving decision-making.

Copper-mediated nucleophilic radiofluorination of [18 F]ß-CFT for positron emission tomography imaging of dopamine transporter.

[18 F]ß-CFT is a positron emission tomography (PET) ligand for imaging of dopamine transporter. It was proved to be a sensitive PET marker to detect presynaptic dopaminergic hypofunction in Parkinson's disease. In recent years, copper-mediated 18 F-fluorination of aryl boronic esters has been successful in some molecules containing aromatic groups. In this study, we describe the novel synthetic strategy of [18 F]ß-CFT by copper-mediated nucleophilic radiofluorination with pinacol-derived aryl boronic esters upon reaction with [18 F]KF/K222 and Cu (OTf)2 (py)4 . The radiolabeling protocol was optimized with [18 F]fluoride elution method and amount of copper catalyst used. [18 F]ß-CFT is obtained from boronic ester precursors in 2.2% to 10.6% non-isolated radiochemical yield (RCY). Purified [18 F]ß-CFT with >99% radiochemical purity (RCP) and high molar activity was obtained in validation runs. The radiolabeling procedure is straightforward and can easily be adapted for clinical use.

Hexavalent lactoside labeled with [18F]AlF for PET imaging of asialoglycoprotein receptor.

Several methods have been developed to label compounds with 18F. However, in general these are laborious and require a multistep synthesis. A method based on the chelation of 18F-aluminum fluoride ([18F]AlF) by 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA) was developed recently. The present work was aimed to radiolabel hexavalent lactoside (NOTA-HL) by [18F]AlF method for PET imaging of asialoglycoprotein receptor (ASGPR). METHODS: hexavalent lactoside was conjugated with the NOTA chelate and labeled with 18F in a one-pot method. The labeling procedure was investigated with different amounts of NOTA-HL and aluminum concentration. Radiochemical yield and radiochemical purity were determined by radio-TLC and radio-HPLC respectively. In vitro stability study of [18F]AlF-HL were carried out. PET/CT imaging of normal mice injected with [18F]AlF-NOTA-HL was performed. RESULTS: The Radiochemical yield of [18F]AlF-NOTA-HL was higher with more precursor and optimal Al+ concentration. The radiochemical purity of labeled product was >95% after purified by Sep-Pak cartridge to remove unbound [18F]AlF. The radiolabeling, including purification, was performed in 30 min [18F]AlF-NOTA-HL exhibited good in vitro stability. PET studies in normal mice revealed high specific accumulation of activity in the liver. CONCLUSION: NOTA-HL could be labeled rapidly and efficiently with aqueous 18F using AlF method. [18F]AlF-NOTA-HL would provide another efficient approach for PET imaging of ASGPR.

Strong Inhibitory Effects of Antisense Probes on Gene Expression through Ultrafast RNA Photocrosslinking.

We have reported the photochemical regulation of the intracellular antisense effect of antisense probes containing a photo-responsive artificial nucleic acid, 3-cyanovinylcarbazole nucleoside (CNV K). Here we focus on the importance of the photocrosslinking rate on the inhibitory effect on gene expression using photocrosslinkable antisense probes (pcASOs). The inhibitory effect of pcASOs on GFP gene expression was dependent on the photocrosslinking rate of 3-cyanovinylcarbazole with d-threoninol (CNV D), CNV K, or psoralen. The ultrafast RNA photocrosslinking induced the formation of a thermally irreversible covalent bond between pcASOs and the target RNA. These ASOs strongly inhibited gene expression only when the photocrosslinking rate was faster than the random walk of branch migration. In addition, pcASOs containing CNV D or CNV K targeted the RNAs with secondary structures. These results indicate the regulatory effect of photocrosslinker and photoirradiation energy using pcASOs on the gene expression level.

Development of single vial kits for preparation of 68 Ga-labelled hexavalent lactoside for PET imaging of asialoglycoprotein receptor.

The aim of this study was to formulate and evaluate the freeze-dried kit of NOTA-hexavalent lactoside (NOTA-HL) for the preparation of 68 Ga-labeled glycoligand for PET imaging of the asialoglycoprotein receptor (ASGPR). 68 GaCl3 was obtained from a commercial 68 Ge/68 Ga generator. Single-vial kits of HL were formulated. Optimization of radiolabeling with 68 Ga, various evaluations of NOTA-HL kits, and in vitro stability study of 68 Ga-HL were carried out. PET/CT imaging of normal mice injected with 68 Ga-NOTA-HL was performed. NOTA-HL kit was successfully formulated. High radiochemical yields (>95%) were obtained by 68 Ga radiolabeling. The NOTA-HL kits were stable for at least 12 months, and 68 Ga-NOTA-HL exhibited good in vitro stability. PET studies in normal mice revealed high specific accumulation of activity in the liver. The NOTA-HL kit was developed for fast 68 Ga labeling. 68 Ga-NOTA-HL showed high specific uptake in liver. The availability of ready-to-use NOTA-HL kits combined with 68 Ge/68 Ga generators would provide an efficient approach for PET imaging of ASGPR.

Ethanol extract of Phellinus merrillii protects against diethylnitrosamine- and 2-acetylaminofluorene-induced hepatocarcinogenesis in rats.

OBJECTIVE: To study whether the ethanol extract of Phellinus merrillii (EPM) has chemopreventive potential against liver carcinogenesis. METHODS: Thirty male Spraque-Dawley rats were randomly divided into control group, EPM control group, hepatocarcinoma control group, low-dose EPM group and high-dose EPM group, 6 in each group. Using the Solt and Farber protocol in a rat model of hepatocarcinogenesis, the chemopreventive effect of EPM on diethylnitrosamine (DEN)-initiated, 2-acetylaminofluorene (2-AAF) and partial hepatectomy (PH)-promoted liver carcinogenesis in rats was evaluated. Basic pathophysiological and histological examinations, together with the serum levels of glutamic oxaloacetic transaminase (sGOT), glutamic pyruvic transaminase (sGPT) and gamma-glutamyl transpeptidase (γ-GT) were measured. RESULTS: Treatment of EPM at the concentration of 2 g/kg body weight in the diet for 8 weeks clearly prevented the development of carcinogenesis and reduced the levels of sGOT, sGPT, and serum γ-GT of rats as compared with the hepatocarcinoma control group (P<0.05 or P<0.01). These phenotypes were accompanied by a significant increase in natural killer cell activity. CONCLUSION: EPM showed a strong liver preventive effect against DEN+2-AAF+PH-induced hepatocarcinogenesis in a rat model.

Biosensor for human IgE detection using shear-mode FBAR devices.

Film bulk acoustic resonators (FBARs) have been evaluated for use as biosensors because of their high sensitivity and small size. This study fabricated a novel human IgE biosensor using shear-mode FBAR devices with c-axis 23°-tilted AlN thin films. Off-axis radio frequency (RF) magnetron sputtering method was used for deposition of c-axis 23°-tilted AlN thin films. The deposition parameters were adopted as working pressure of 5 mTorr, substrate temperature of 300°C, sputtering power of 250 W, and 50 mm distance between off-axis and on-axis. The characteristics of the AlN thin films were investigated by X-ray diffraction and scanning electron microscopy. The frequency response was measured with an HP8720 network analyzer with a CASCADE probe station. The X-ray diffraction revealed (002) preferred wurtzite structure, and the cross-sectional image showed columnar structure with 23°-tilted AlN thin films. In the biosensor, an Au/Cr layer in the FBAR backside cavity was used as the detection layer and the Au surface was modified using self-assembly monolayers (SAMs) method. Then, the antigen and antibody were coated on biosensor through their high specificity property. Finally, the shear-mode FBAR device with k t (2) of 3.18% was obtained, and the average sensitivity for human IgE detection of about 1.425 × 10(5) cm(2)/g was achieved.

Identification of CD24 as a cancer stem cell marker in human nasopharyngeal carcinoma.

Cancer stem cells (CSCs) represent a unique sub-population of tumor cells with the ability to initiate tumor growth and sustain self-renewal. Although CSC biomarkers have been described for various tumors, only a few markers have been identified for nasopharyngeal carcinoma (NPC). In this study, we show that CD24+ cells isolated from human NPC cell lines express stem cell genes (Sox2, Oct4, Nanog, Bmi-1, and Rex-1), and show activation of the Wnt/ß-catenin signaling pathway. CD24+ cells possess typical CSC characteristics that include enhanced cell proliferation, increased colony and sphere formation, maintenance of cell differentiation potential in prolonged culture, and enhanced resistance to chemotherapeutic drugs. Notably, CD24+ cells produce tumors following inoculation of as few as 500 cells in immunodeficient NOD/SCID mice. CD24+ cells further show increased invasion ability in vitro, which correlates with enhanced expression of matrix metalloproteinase 2 and 9. In summary, our results suggest that CD24 represents a novel CSC biomarker in NPC.

Autophagy activators rescue and alleviate pathogenesis of a mouse model with proteinopathies of the TAR DNA-binding protein 43.

TDP-43 is a multifunctional DNA/RNA-binding protein that has been identified as the major component of the cytoplasmic ubiquitin (+) inclusions (UBIs) in diseased cells of frontotemporal lobar dementia (FTLD-U) and amyotrophic lateral sclerosis (ALS). Unfortunately, effective drugs for these neurodegenerative diseases are yet to be developed. We have tested the therapeutic potential of rapamycin, an inhibitor of the mammalian target of rapamycin (mTOR) and three other autophagy activators (spermidine, carbamazepine, and tamoxifen) in a FTLD-U mouse model with TDP-43 proteinopathies. Rapamycin treatment has been reported to be beneficial in some animal models of neurodegenerative diseases but not others. Furthermore, the effects of rapamycin treatment in FTLD-U have not been investigated. We show that rapamycin treatment effectively rescues the learning/memory impairment of these mice at 3 mo of age, and it significantly slows down the age-dependent loss of their motor function. These behavioral improvements upon rapamycin treatment are accompanied by a decreased level of caspase-3 and a reduction of neuron loss in the forebrain of FTLD-U mice. Furthermore, the number of cells with cytosolic TDP-43 (+) inclusions and the amounts of full-length TDP-43 as well as its cleavage products (35 kDa and 25 kDa) in the urea-soluble fraction of the cellular extract are significantly decreased upon rapamycin treatment. These changes in TDP-43 metabolism are accompanied by rapamycin-induced decreases in mTOR-regulated phospho-p70 S6 kinase (P-p70) and the p62 protein, as well as increases in the autophagic marker LC3. Finally, rapamycin as well as spermidine, carbamazepine, and tamoxifen could also rescue the motor dysfunction of 7-mo-old FTLD-U mice. These data suggest that autophagy activation is a potentially useful route for the therapy of neurodegenerative diseases with TDP-43 proteinopathies.

Activation of NK cell cytotoxicity by the natural compound 2,3-butanediol.

The natural compound 2,3-BTD has diverse physiological effects in a range of organisms, including acting as a detoxifying product of liver alcohol metabolism in humans and ameliorating endotoxin-induced acute lung injury in rats. In this study, we reveal that 2,3-BTD enhances NK cell cytotoxic activity in human pNK cells and NK92 cells. Treatment of NK cells with 2,3-BTD increased perforin expression in a dose-dependent manner. This was accompanied by elevated JNK and ERK1/2 MAPK activities and enhanced expression of NKG2D/NCRs, upstream signaling molecules of the MAPK pathways. The 2,3-BTD effect was inhibited by pretreatment with inhibitors of JNK (SP) or ERK1/2 (PD) or by depleting NKG2D/NCRs or JNK1 or ERK2 with siRNA. These results indicate that 2,3-BTD activates NK cell cytotoxicity by NKG2D/NCR pathways and represent the first report of the 2,3-BTD effect on activation of innate immunity cells.

A novel exon 15-deleted, splicing variant of Slit2 shows potential for growth inhibition in addition to invasion inhibition in lung cancer.

BACKGROUND: The axon guidance cue molecule Slit2 has been shown to suppress cancer cell invasion. However, the role of Slit2 in growth inhibition is still controversial. The authors identified a novel exon 15 (AKEQYFIP)-deleted slit2, located at the end of the second leucine-rich repeat (LRR2). Because LRR2 interacts with Robo1 receptor to inhibit invasion, they hypothesized that exon 15 plays an important role in modulating Slit2 function. METHODS: Slit2 expression was assessed via microarray analysis in 27 lung adenocarcinomas. Exon 15-deleted slit2 (slit2-ΔE15) and exon 15-containing slit2 (slit2-WT) were cloned and expressed in the CL1-5 lung cancer cell line. The effect of exon 15 on Slit2-mediated cell growth was evaluated by a xenografted model and in vitro cell growth assays. The effect of exon 15 on Slit2-mediated invasion was analyzed with a modified Boyden chamber in vitro. RESULTS: Tumor growth from CL1-5/Slit2-WT cells was comparable to that from CL1-5 cells bearing empty vector. However, tumor size from CL1-5/Slit2-ΔE15 cells was much smaller than that from Slit2-WT cells or vector control cells in the xenografted model. In vitro analyses demonstrated that Slit2-WT inhibits invasion of CL1-5 cells. In addition to inhibiting invasion, Slit2-ΔE15 greatly suppresses cell growth. CONCLUSIONS: The data demonstrated that exon 15 modulates Slit2 function in growth inhibition of lung cancer cells. Because slit2-ΔE15 splice variant is present in low invasive cancer cells and nontumor lung tissues, loss of this splice variant is an important event in tumor progression and invasion.

Analgesic effects and the mechanisms of anti-inflammation of hispolon in mice.

Hispolon, an active ingredient in the fungi Phellinus linteus was evaluated with analgesic and anti-inflammatory effects. Treatment of male ICR mice with hispolon (10 and 20 mg/kg) significantly inhibited the numbers of acetic acid-induced writhing response. Also, our result showed that hispolon (20 mg/kg) significantly inhibited the formalin-induced pain in the later phase (P<.01). In the anti-inflammatory test, hispolon (20 mg/kg) decreased the paw edema at the fourth and fifth hour after λ-carrageenin (Carr) administration, and increased the activities of superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GRx) in the liver tissue. We also demonstrated that hispolon significantly attenuated the malondialdehyde (MDA) level in the edema paw at the fifth hour after Carr injection. Hispolon (10 and 20 mg/kg) decreased the nitric oxide (NO) levels on both the edema paw and serum level at the fifth hour after Carr injection. Also, hispolon (10 and 20 mg/kg) diminished the serum TNF-α at the fifth hour after Carr injection. The anti-inflammatory mechanisms of hispolon might be related to the decrease in the level of MDA in the edema paw by increasing the activities of SOD, GPx and GRx in the liver. It probably exerts anti-inflammatory effects through the suppression of TNF-α and NO.

RssAB-FlhDC-ShlBA as a major pathogenesis pathway in Serratia marcescens.

Serratia marcescens has long been recognized as an important opportunistic pathogen, but the underlying pathogenesis mechanism is not completely clear. Here, we report a key pathogenesis pathway in S. marcescens comprising the RssAB two-component system and its downstream elements, FlhDC and the dominant virulence factor hemolysin ShlBA. Expression of shlBA is under the positive control of FlhDC, which is repressed by RssAB signaling. At 37°C, functional RssAB inhibits swarming, represses hemolysin production, and promotes S. marcescens biofilm formation. In comparison, when rssBA is deleted, S. marcescens displays aberrant multicellularity favoring motile swarming with unbridled hemolysin production. Cellular and animal infection models further demonstrate that loss of rssBA transforms this opportunistic pathogen into hypervirulent phenotypes, leading to extensive inflammatory responses coupled with destructive and systemic infection. Hemolysin production is essential in this context. Collectively, a major virulence regulatory pathway is identified in S. marcescens.

Elevated expression of TDP-43 in the forebrain of mice is sufficient to cause neurological and pathological phenotypes mimicking FTLD-U.

TDP-43 is a multifunctional DNA/RNA-binding factor that has been implicated in the regulation of neuronal plasticity. TDP-43 has also been identified as the major constituent of the neuronal cytoplasmic inclusions (NCIs) that are characteristic of a range of neurodegenerative diseases, including the frontotemporal lobar degeneration with ubiquitin(+) inclusions (FTLD-U) and amyotrophic lateral sclerosis (ALS). We have generated a FTLD-U mouse model (CaMKII-TDP-43 Tg) in which TDP-43 is transgenically overexpressed in the forebrain resulting in phenotypic characteristics mimicking those of FTLD-U. In particular, the transgenic (Tg) mice exhibit impaired learning/memory, progressive motor dysfunction, and hippocampal atrophy. The cognitive and motor impairments are accompanied by reduced levels of the neuronal regulators phospho-extracellular signal-regulated kinase and phosphorylated cAMP response element-binding protein and increased levels of gliosis in the brains of the Tg mice. Moreover, cells with TDP-43(+), ubiquitin(+) NCIs and TDP-43-deleted nuclei appear in the Tg mouse brains in an age-dependent manner. Our data provide direct evidence that increased levels of TDP-43 protein in the forebrain is sufficient to lead to the formation of TDP-43(+), ubiquitin(+) NCIs and neurodegeneration. This FTLD-U mouse model should be valuable for the mechanistic analysis of the role of TDP-43 in the pathogenesis of FTLD-U and for the design of effective therapeutic approaches of the disease.

1-Deoxynojirimycin inhibits metastasis of B16F10 melanoma cells by attenuating the activity and expression of matrix metalloproteinases-2 and -9 and altering cell surface glycosylation.

1-Deoxynojirimycin (1-DNJ), an iminosugar rich in mulberry, has been shown to possess antimetastatic potential. The antimetastatic mechanisms of 1-DNJ in melanoma B16F10 cells were studied, as were the antimetastatic activity (cell adhesion, migration, and invasion) of 1-DNJ, matrix metalloproteinases (MMP-2 and MMP-9), tissue inhibitors of metalloproteinase (TIMP-1 and TIMP-2) mRNA, and flow cytometric analysis of cell surface in melanoma B16F10 cells. 1-DNJ significantly inhibited invasion, migration, and cell-matrix adhesion and markedly decreased MMP-2 and MMP-9 activity and mRNA expression. In contrast, 1-DNJ effectively enhanced the expression of TIMP-2 mRNA. In addition, 1-DNJ significantly decreased abnormal glycosylation and/or sialylation on B16F10 melanoma cell surface but increased the levels of α-mannose. Thus, the antimetastatic effects of 1-DNJ against B16F10 melanoma cells are likely associated with its attenuated activities and expression of MMP-2/9, enhancement of the TIMP-2 mRNA expression, and alterations of the cell surface-binding motif. These results suggest that 1-DNJ may be useful as an adjuvant of antimetastatic agents such as cisplatin.