Revolutionizing Drug Targeting Strategies: Integrating Artificial Intelligence and Structure-Based Methods in PROTAC Development.

PROteolysis TArgeting Chimera (PROTAC) is an emerging technology in chemical biology and drug discovery. This technique facilitates the complete removal of the target proteins that are "undruggable" or challenging to target through chemical molecules via the Ubiquitin-Proteasome System (UPS). PROTACs have been widely explored and outperformed not only in cancer but also in other diseases. During the past few decades, several academic institutes and pharma companies have poured more efforts into PROTAC-related technologies, setting the stage for several major degrader trial readouts in clinical phases. Despite their promising results, the formation of robust ternary orientation, off-target activity, poor permeability, and binding affinity are some of the limitations that hinder their development. Recent advancements in computational technologies have facilitated progress in the development of PROTACs. Researchers have been able to utilize these technologies to explore a wider range of E3 ligases and optimize linkers, thereby gaining a better understanding of the effectiveness and safety of PROTACs in clinical settings. In this review, we briefly explore the computational strategies reported to date for the formation of PROTAC components and discuss the key challenges and opportunities for further research in this area.

Iron-Fur complex suppresses the expression of components of the cyclo-(Phe-Pro)-signaling regulatory pathway in Vibrio vulnificus.

In the human pathogen Vibrio vulnificus, the quorum-sensing (QS) signal molecule cyclo-(L-phenylalanine-L-proline) (cFP) plays a critical role in triggering a signaling pathway involving the components LeuO-vHUαß-RpoS-KatG via the membrane signal receptor ToxR. In this study, we investigated the impact of iron on the expression of these signaling components. We found that the transcription of the membrane sensor protein ToxR was not significantly affected by Fur-iron. However, Fur-iron repressed the transcription of genes encoding all the downstream cytoplasmic components in this pathway by binding to the upstream regions of these genes. Consequently, the expression of genes regulated by the alternative sigma factor RpoS, as well as the resistance to hydrogen peroxide conferred by KatG, were repressed. Additionally, we observed that in Vibrio cholerae, genes dependent on ToxR showed higher expression levels in a fur-deletion mutant compared to the wild type. These findings indicate that iron, in association with Fur, represses virtually all the cytoplasmic components responsible for the ToxR-dependent cFP-signaling pathways in these two pathogenic Vibrio species. This study, along with our previous reports demonstrating the repression of components involved in AI-2 dependent QS signaling by Fur-iron, highlights the crucial role of iron in quorum-sensing regulation, which is closely associated with the pathogenicity of this human pathogen.

Ultra-thin light-weight laser-induced-graphene (LIG) diffractive optics.

The realization of hybrid optics could be one of the best ways to fulfill the technological requirements of compact, light-weight, and multi-functional optical systems for modern industries. Planar diffractive lens (PDL) such as diffractive lenses, photonsieves, and metasurfaces can be patterned on ultra-thin flexible and stretchable substrates and be conformally attached on top of arbitrarily shaped surfaces. In this review, we introduce recent research works addressed to the design and manufacturing of ultra-thin graphene optics, which will open new markets in compact and light-weight optics for next-generation endoscopic brain imaging, space internet, real-time surface profilometry, and multi-functional mobile phones. To provide higher design flexibility, lower process complexity, and chemical-free process with reasonable investment cost, direct laser writing (DLW) of laser-induced-graphene (LIG) is actively being applied to the patterning of PDL. For realizing the best optical performances in DLW, photon-material interactions have been studied in detail with respect to different laser parameters; the resulting optical characteristics have been evaluated in terms of amplitude and phase. A series of exemplary laser-written 1D and 2D PDL structures have been actively demonstrated with different base materials, and then, the cases are being expanded to plasmonic and holographic structures. The combination of these ultra-thin and light-weight PDL with conventional bulk refractive or reflective optical elements could bring together the advantages of each optical element. By integrating these suggestions, we suggest a way to realize the hybrid PDL to be used in the future micro-electronics surface inspection, biomedical, outer space, and extended reality (XR) industries.

Effects of washing solution temperature on the biocompatibility and mechanical properties of 3D-Printed dental resin material.

The use of digital manufacturing, particularly additive manufacturing using three-dimensional (3D) printing, is expanding in the field of dentistry. 3D-printed resin appliances must undergo an essential process, post-washing, to remove residual monomers; however, the effect of the washing solution temperature on the biocompatibility and mechanical properties remains unclear. Therefore, we processed 3D-printed resin samples under different post-washing temperatures (without temperature control (N/T), 30 °C, 40 °C, and 50 °C) for different durations (5, 10, 15, 30, and 60 min) and evaluated the degree of conversion rate, cell viability, flexural strength, and Vickers hardness. Increasing the washing solution temperature significantly improved the degree of conversion rate and cell viability. Conversely, increasing the solution temperature and time decreased the flexural strength and microhardness. This study confirmed that the washing temperature and time influence the mechanical and biological properties of the 3D-printed resin. Washing 3D-printed resin at 30 °C for 30 min was most efficient to maintain optimal biocompatibility and minimize changes of mechanical properties.

Cycloastragenol activation of telomerase improves ß-Klotho protein level and attenuates age-related malfunctioning in ovarian tissues.

Age-related deterioration in the reproductive capacity of women is directly related to the poor developmental potential of ovarian follicles. Although telomerase plays a key role in female fertility, TERT-targeting therapeutic strategies for age-related female infertility have yet to be investigated. This study elucidated the effect of Telomerase activation on mice ovaries and more specifically on Klb (ß-Klotho) gene expression, which is linked to ageing, female hormonal regulation, and cyclicity. The homology-based 3D model of hTERT was used to predict its binding mode of Cycloastragenol (CAG) using molecular docking and molecular dynamics simulations. Based on docking score, simulation behavior, and interaction with hTERT residues it was observed that CAG could bind with the hTERT model. CAG treatment to primary cultured mouse granulosa cells and activation of telomerase was examined via telomerase activity assay (Mouse TE (telomerase) ELISA Kit) and telomere length by quantitative fluorescence in situ hybridization. CAG mediated telomerase also significantly improved ß-Klotho protein level in the aged granulosa cells. To demonstrate that ß-Klotho is telomerase dependent, the TERT was knocked down via siRNA in granulosa cells and protein level of ß-Klotho was examined. Furthermore, CAG-mediated telomerase activation significantly enhanced the level of Klb and recovered ovarian follicles in the D-galactose (D-gal)-induced ovarian ageing mouse model. Moreover, Doxorubicin-induced ovarian damage, which changes ovarian hormones, and inhibit follicular growth was successfully neutralized by CAG activated telomerase and its recovery of ß-Klotho level. In conclusion, TERT dependent ß-Klotho regulation in ovarian tissues is one of the mechanisms, which can overcome female infertility.

Influence of postwashing process on the elution of residual monomers, degree of conversion, and mechanical properties of a 3D printed crown and bridge materials.

OBJECTIVES: This study aimed to determine the effects of the postwashing method and time on the mechanical properties and biocompatibility of three-dimensional (3D) printed crown and bridge resin. METHODS: DLP (digital light processing)-printed specimens produced from Nextdent crown & bridge (C&B) resins were washed separately using an ultrasonic bath and rotary washer with TPM (tripropylene glycol monomethyl ether) for 3 min, 6 min, 10 min, 20 min, and 1 h. Postcuring was applied for 30 min to each specimen after the washing process. The flexural strength, Vickers hardness, water sorption and solubility, degree of conversion (DC), elution of residual monomers, and biocompatibility of the specimens were evaluated. RESULTS: The ultrasonic bath showed greater washing efficacy by reducing the residual HEMA (2-hydroxyethyl methacrylate) from 2.0634 ppm to 0.1456 ppm and reducing the residual TEGDMA (triethylene glycol dimethacrylate) from 1.4862 ppm to 0.1484 ppm. With prolonged washing, the flexural strength significantly decreased from 129.67 ± 6.66 MPa (mean±standard deviation) to 103.17 ± 7.20 MPa, while the Vickers hardness increased slightly for the first 6 min and then decreased thereafter significantly. The DC was 87.78 ± 1.34% after 3 min and then gradually decreased with extended washing time. The cytotoxicity significantly decreases with the increment of the washing time. SIGNIFICANCE: The washing effect on the elution of residual monomers was better for an ultrasonic bath than for a rotary washer. Extending the washing time reduces the mechanical properties and cytotoxicity of the Nextdent C&B resin.

Accuracy of 3D printed models and implant-analog positions according to the implant-analog-holder offset, inner structure, and printing layer thickness: an in-vitro study.

PURPOSE: This study aimed to determine how the implant-analog-holder (IAH) offset, inner structure, and printing layer thickness influence the overall accuracy and local implant-analog positional changes of 3D printed dental models. METHODS: Specimens in 12 experimental groups (8 specimens per group) with different IAH offsets, inner structures, and printing layer thicknesses were printed in three dimensions using an LCD printer (Phrozen Shuffle) and digitized by a laboratory scanner (Identica T500). The trueness and precision of the printed model as well as the angular distortion, depth deviation, and linear distortion of the implant analog were evaluated using three-way ANOVA. RESULTS: The positional accuracy was significantly higher for IAH offsets of 0.04 mm and 0.06 mm than for one of 0.08 mm, for a hollow than a solid inner structure, and for a printing layer thickness of 100 µm than for one of 50 µm (all P<.001). CONCLUSIONS: The accuracies of the 3D printed models and the implant-analog positions were significantly affected by the IAH offset, inner structure, and printing layer thickness. CLINICAL SIGNIFICANCE: Given the observation of this study, premeditating the IAH offset of 0.06 mm, hollow inner structure, and printing layer thickness of 100 µm before printing can help clinicians reach the optimum overall printing accuracy and minimum the local positional changes of the implant-analogs.

Hesperetin activated SIRT1 neutralizes cadmium effects on the early bovine embryo development.

Cadmium (Cd) is a major environmental contaminant that has been linked to oocyte quality reduction and early embryo mortality in various in vivo studies. In this study, we investigated the mechanism of Cd-induced mitochondrial toxicity in bovine in vitro matured oocytes, primary cultured bovine cumulus cells, and in vitro developed bovine embryos. Cd significantly reduced PPARGC1A (PGC-1α) and nuclear respiratory factors, which leads to mitochondrial damage and hence reduction in oocyte maturation and embryo development. NAD-dependent deacetylase sirtuin-1 (SIRT1) is the upstream marker of PGC-1α and nuclear respiratory factors, and its activation significantly mitigated Cd-induced mitochondrial damage. For SIRT1 activation, we used Hesperetin (Hsp), a citrus flavonoid and a potent activator of SIRT1. The molecular docking approach was used to investigate the binding of hesperetin to bovine SIRT1, which revealed that hesperetin creates polar and non-polar interactions with residues that are reported essential for the activation of SIRT1. Furthermore, the SIRT1 enzymatic activity was measured in primary cultured bovine granulosa cells after hesperetin treatment. To further confirm the SIRT1-dependent effects of hesperetin we used a specific inhibitor of SIRT1 (EX527), which significantly (p < 0.05) reduced the effects of hesperetin on embryo mitochondria. Next, we treated hesperetin and Cd to early bovine embryos and discovered a significant (p 0.05) increase in PGC-1, NRF1, and NFE2L2 protein expression as well as embryo development recovery. Thus, we came to the conclusion that hesperetin can activate PGC-1 and nuclear respiratory factors via SIRT1, which can greatly reduce Cd-induced mitochondrial toxicity and promote mitochondrial biogenesis in early bovine embryos.

Impact of scanning strategy on the accuracy of complete-arch intraoral scans: a preliminary study on segmental scans and merge methods.

PURPOSE: This study investigated the accuracy of full-arch intraoral scans obtained by various scan strategies with the segmental scan and merge methods. MATERIALS AND METHODS: Seventy intraoral scans (seven scans per group) were performed using 10 scan strategies that differed in the segmental scan (1, 2, or 3 segments) and the scanning motion (straight, zigzag, or combined). The three-dimensional (3D) geometric accuracy of scan images was evaluated by comparison with a reference image in an image analysis software program, in terms of the arch shape discrepancies. Measurement parameters were the intermolar distance, interpremolar distance, anteroposterior distance, and global surface deviation. One-way analysis of variance and Tukey honestly significance difference post hoc tests were carried out to compare differences among the scan strategy groups (α = .05). RESULTS: The linear discrepancy values of intraoral scans were not different among scan strategies performed with the single scan and segmental scan methods. In general, differences in the scan motion did not show different accuracies, except for the intermolar distance measured under the scan conditions of a 3-segmental scan and zigzag motion. The global surface deviations were not different among all scan strategies. CONCLUSION: The segmental scan and merge methods using two scan parts appear to be reliable as an alternative to the single scan method for full-arch intraoral scans. When three segmental scans are involved, the accuracy of complete arch scan can be negatively affected.

Fabrication of a porous polyacrylonitrile nanofiber adsorbent for removing radioactive 60Co.

A Co2+ adsorbent was prepared using electrospun porous polyacrylonitrile (PAN) nanofibers, featuring easy recovery for reuse compared with a nanoparticle-based adsorbent. As an efficient ligand for Co2+, ethylenediaminetetraacetic acid (EDTA) was introduced on the surface of porous PAN nanofibers with the aid of a branched polyethyleneimine (PEI) linker to obtain an adsorbent with carboxylic acid groups. On the adsorbent surface, the carboxylic acid and amine groups from EDTA could adsorb Co2+ via ion exchange and chelation, and amine groups from PEI that remained after EDTA functionalization played a role in coordinating Co2+. The amine and carboxylic acid groups were simultaneously involved in the adsorption on the surface, making it possible to remove Co2+ over a wide pH range. An investigation of the adsorption isotherms and kinetics of the nanofibrous adsorbent indicated that monolayer chemisorption was achieved with a maximum Co2+ adsorption capacity of 8.32 mg/g. In addition, radioactive 60Co was efficiently removed by the adsorbent with a removal extent of more than 98%. Considering the easy separation from Co2+ solution and regeneration of the nanofibrous adsorbent and its availability in a wide pH range, the adsorbent has great advantages in practical applications.

PRRX1 is a master transcription factor of stromal fibroblasts for myofibroblastic lineage progression.

Although stromal fibroblasts play a critical role in cancer progression, their identities remain unclear as they exhibit high heterogeneity and plasticity. Here, a master transcription factor (mTF) constructing core-regulatory circuitry, PRRX1, which determines the fibroblast lineage with a myofibroblastic phenotype, is identified for the fibroblast subgroup. PRRX1 orchestrates the functional drift of fibroblasts into myofibroblastic phenotype via TGF-ß signaling by remodeling a super-enhancer landscape. Such reprogrammed fibroblasts have myofibroblastic functions resulting in markedly enhanced tumorigenicity and aggressiveness of cancer. PRRX1 expression in cancer-associated fibroblast (CAF) has an unfavorable prognosis in multiple cancer types. Fibroblast-specific PRRX1 depletion induces long-term and sustained complete remission of chemotherapy-resistant cancer in genetically engineered mice models. This study reveals CAF subpopulations based on super-enhancer profiles including PRRX1. Therefore, mTFs, including PRRX1, provide another opportunity for establishing a hierarchical classification system of fibroblasts and cancer treatment by targeting fibroblasts.

Effect of luxS encoding a synthase of quorum-sensing signal molecule AI-2 of Vibrio vulnificus on mouse gut microbiome.

Autoinducer-2 (AI-2), a quorum-sensing signal molecule from the human pathogen Vibrio vulnificus, was assessed for its effect on the gut microbiome of mice. For this, we employed 16S rRNA sequencing to compare the gut microbiome of mice infected with either wild-type V. vulnificus or with the isotype ΔluxS that has a deletion in luxS which encodes the biosynthetic function of AI-2. The relative ratio of wild-type Vibrio species in the jejunum and ileum of mice infected with the wild type was significantly higher than that in mice infected with ΔluxS, suggesting that AI-2 plays an important role in the colonization of V. vulnificus in the small intestine. The bacterial composition in the gut of mice infected with ΔluxS comprises a higher proportion of Firmicutes, composed mainly of Lactobacillus, compared to the mice infected with wild-type cells. In the large intestine, Vibrio species were barely detected regardless of genetic background. Three Lactobacillus spp. isolated from fecal samples from mice infected with ΔluxS manifested significant antibacterial activities against V. vulnificus. Culture supernatants from these three species were dissolved by HPLC, and a substance in fractions showing inhibitory activity against V. vulnificus was determined to be lactic acid. Our results suggest that luxS in V. vulnificus affects not only the ability of the species to colonize the host gut but also its susceptibility to the growth-inhibiting activity of commensal bacteria including Lactobacillus. KEY POINTS: • Gut microbiomes of ΔluxS-infected and WT Vibrio-infected mice differed greatly. • Difference was most prominent in the jejunum and ileum compared to the duodenum or large intestine. • In the small and large intestines of mice, the relative proportions of Vibrio and Lactobacillus species showed a negative relationship. • Effector molecules produced by Lactobacillus in mouse gut inhibit Vibrio growth.

Frequency of an X-Linked Maternal Variant of the Bovine FOXP3 Gene Associated with Infertility in Different Cattle Breeds: A Pilot Study.

Immune adaptation plays an essential role in determining pregnancy, which has been shown to be dependent on sufficient immunological tolerance mediated by FOXP3+ regulatory T cells. Recently, an X-linked maternal single-nucleotide polymorphism (SNP), located 2175 base pairs upstream of the start codon in the bovine FOXP3 gene (NC_037357.1: g.87298881A>G, rs135720414), was identified in Japanese Black (JB: Bos taurus) cows in association with recurrent infertility. However, with the exception of JB cows, the frequency of this SNP has yet to be studied in other cow populations. In this study, we thus aimed to evaluate the frequency of this SNP in different cow breeds. Between 2018 and 2021, a total of 809 DNA samples were obtained from 581 JB, 73 Holstein Friesian (HF: B. taurus), 125 Korean Hanwoo (KH: B. taurus coreanae), and 30 Indonesian Madura (IM: a crossbreed between B. indicus and B. javanicus) cows, which were genotyped using a TaqMan probe-based real-time polymerase chain reaction assay designed in this study. The frequency of the G allele was found to be relatively high in local IM (0.700), moderate in dairy HF (0.466), and low in beef JB (0.250) and KH (0.112) cows, with differences in the frequencies between each group being shown to be statistically significant (p < 0.005) using Fisher's exact test. The results obtained in this study indicate that the G allele frequencies of the identified the SNP differ markedly in different breeds of taurine and indicine cattle. Given these findings, it would thus be important to evaluate the relationships between high frequencies of the G allele and infertility in different breeds.

Influence of different postcuring parameters on mechanical properties and biocompatibility of 3D printed crown and bridge resin for temporary restorations.

This study analyzed the flexural properties, Vickers hardness, degree of conversion (DC), and cell viability of 3D printed crown and bridge resin postcured using various types of postcuring equipment (PCE). 3D printed specimens were postcured for various times using different types of 3D printing PCE [for 5, 15, and 30 min using LC 3D Print Box (LC), Form Cure (FC), Cure M (CM), and Veltz 3D (VE) devices] and the VALO handheld light-curing (VA) device for 20, 40, and 60 s. Neither the flexural strength (132.27-145.79 MPa) nor the flexural modulus (1.52-1.83 GPa) differed significantly when postcuring for 30 min using the LC, FC, CM, or VE device, or for 20, 40, or 60 s of postcuring using the VA device (p > 0.05). The Vickers hardness was highest after 30 min of postcuring for all groups, and varied significantly with the postcuring time in the LC (p < 0.001) and CM (p < 0.001) groups. DC was significantly higher for the 5-min CM group (84.97 ± 4.02%) than for the GS, 30-min FC, 5-min VE, and 20-s VA groups. Cell viability of the postcured resin specimens was 56.46-92.29%, and varied significantly in the CM and VE groups according to the postcuring time (p < 0.05). Confocal laser scanning microscopy observations showed well-developed cell morphology and numerous cell-cell contacts in all groups except the GS group. This study found that the use of different types of PCE did not significantly affect the flexural properties of 3D printed crown and bridge resin, whereas there were significant variations in DC, Vickers hardness, and cell viability.

Quorum sensing and iron-dependent coordinated control of autoinducer-2 production via small RNA RyhB in Vibrio vulnificus.

Roles for the non-coding small RNA RyhB in quorum-sensing and iron-dependent gene modulation in the human pathogen V. vulnificus were assessed in this study. Both the quorum sensing master regulator SmcR and the Fur-iron complex were observed to bind to the region upstream of the non-coding small RNA RyhB gene to repress expression, which suggests that RyhB is associated with both quorum-sensing and iron-dependent signaling in this pathogen. We found that expression of LuxS, which is responsible for the biosynthesis of autoinducer-2 (AI-2), was higher in wild type than in a ryhB-deletion isotype. RyhB binds directly to the 5'-UTR (untranslated region) of the luxS transcript to form a heteroduplex, which not only stabilizes luxS mRNA but also disrupts the secondary structure that normally obscures the translational start codon and thereby allows translation of LuxS to begin. The binding of RyhB to luxS mRNA requires the chaperone protein Hfq, which stabilizes RyhB. These results demonstrate that the small RNA RyhB is a key element associated with feedback control of AI-2 production, and that it inhibits quorum-sensing signaling in an iron-dependent manner. This study, taken together with previous studies, shows that iron availability and cell density signals are funneled to SmcR and RyhB, and that these regulators coordinate cognate signal pathways that result in the proper balance of protein expression in response to environmental conditions.

Development of novel fluorescence-based and label-free noncanonical G4-quadruplex-like DNA biosensor for facile, specific, and ultrasensitive detection of fipronil.

Fipronil is a broad-spectrum insecticide widely used in agriculture and residential areas; its indiscriminate use leads to environmental pollution and poses health hazards. Early detection of fipronil is critical to prevent the deleterious effects. However, current insecticide analysis methods such as HPLC, LC/MS, and GC/MS are incompetent; they are costly, immobile, time-consuming, laborious, and need skilled technicians. Hence, a sensitive, specific, and cheap biosensor are essential to containing the contamination. Here, we designed two novel biosensors-the first design relied on fluorescent labeling/quenching, while the second sensor focused on label-free detection using Thioflavin T displacement. Altogether, we identified four candidate aptamers, predicted secondary structures, and performed 3D molecular modeling to predict the binding pocket of fipronil in FiPA6B aptamer. Furthermore, the aptameric sensors showed high sensitivity to fipronil of sub-ppb level LOD, attributed to stringent experimental design. The biosensors displayed high specificity against other phenylpyrazole insecticides and demonstrated robust sensitivity for fipronil in real samples like cabbage and cucumber. Notably, to the best of our knowledge, this is the first demonstration of noncanonical G4-quadruplex-like aptamer binding to fipronil, verified using CD spectroscopy. Such aptasensors possess considerable potential for real-time measurements of hazardous insecticides as point-of-care technology.

Validation of ZMYND8 as a new treatment target in hepatocellular carcinoma.

BACKGROUND: ZMYND8 (Zinc finger MYND (Myeloid, Nervy and DEAF-1)-type containing 8) has been known to play an important role in tumor regulation in various types of cancer. However, the results of ZMYND8 expression and their clinical significance in hepatocellular carcinoma (HCC) have not yet been published. In the present study, we investigate the expression of ZMYND8 protein and mRNA in HCC and elucidate its prognostic significance. METHODS: ZMYND8 protein and mRNA expression in 283 and 234 HCCs were investigated using immunohistochemistry and microarray gene expression profiling data. The relationships between ZMYND8 expression with clinicopathologic features and prognosis of HCC patients were evaluated. Furthermore, we performed the invasion, migration, apoptosis, soft agar formation assay and sphere formation assay in HCC cell lines, and evaluated tumorigenicity in a nude mouse model, after ZMYND8 knockdown. RESULTS: Overexpression of ZMYND8 protein and mRNA was observed in 20.5% and 26.9% of HCC cases, respectively. High ZMYND8 expression showed significant correlations with microvascular invasion, high Edmondson grade, advanced American Joint Committee on Cancer, and increased alpha-fetoprotein level. ZMYND8 mRNA overexpression was an independent prognostic factor for predicting early recurrence as well as short recurrence-free survival (RFS). Downregulation of ZMYND8 reduced migration and invasion of HCC cells, and promoted apoptosis of HCC cells in an in vitro model. In a xenograft nude mouse model, knockdown of ZMYND8 significantly reduced tumor growth. CONCLUSION: ZMYND8 mRNA overexpression could be a prognostic marker of shorter RFS in HCC patients after curative resection. ZMYND8 might play an important role in the proliferation and progression of HCC and could be a promising candidate for targeted therapy.

Reliability Verification of Damping Capacity Assessment Through In Vitro Analysis of Implant Micromotion in Peri-implant Bone Loss Model.

PURPOSE: This in vitro study aimed to determine the efficacy of a damping capacity assessment in evaluating the implant stability in a simulated peri-implant bone loss model. MATERIALS AND METHODS: The same type of implant was placed sequentially in 0.5-mm-depth increments in polyurethane bone of a constant density, resulting in 11 specimens with varying surrounding bone levels. The implant stability was evaluated by a damping capacity assessment consisting of six consecutive impacts in one set. The damping results, including the contact time and stability index, were measured by three repeated sets of stability tests for each specimen. All implant micromotions were recorded in real time using a laser scanning vibrometer during these stability tests. The micromotions were analyzed in terms of three parameters: maximum displacement, expected mobility, and vibration frequency. Additionally, two other stability indices were acquired three times each for reference. Pearson correlation analysis was used to confirm the correlations among all the variables; P < .05 was considered statistically significant. RESULTS: As the peri-implant bone level increased, the contact time results decreased gradually from 502 to 290 µs, and the stability index increased from 55 to 78. The implant micromotions of all specimens showed a damped sine waveform graph, which can be divided into impact displacement and self-vibration patterns by the contact end points. As the implant stability increased, these contact end points converged toward the third peak, the maximum displacement and expected mobility decreased, and the vibration frequency increased (ρ = -0.85, -0.88, and 0.99, respectively). Two other stability indices reflected the implant stability due to peri-implant bone loss. The statistical analysis indicated significant correlations among all measured variables; in particular, the three stability indices exhibited high correlations with each other (ρ = 0.99, -0.99, and -1.00, respectively). CONCLUSION: Within the limitations of this in vitro study, the implant stability measured by a damping capacity assessment was suitable for investigating the extent of implant micromotions, which were determined by 0.5-mm horizontal changes in the peri-implant bone level.

Validation of ORAOV1 as a new treatment target in hepatocellular carcinoma.

PURPOSE: Chromosome 11q13.2, which contains genes cyclin D1 (CCND1), fibroblast growth factor 19 (FGF19), and Oral Cancer Overexpressed 1 (ORAOV1), is the most highly amplified peak in hepatocellular carcinoma (HCC). CCND1 and FGF19 have been already suggested as therapeutic targets of HCC, but the role of ORAOV1 in carcinogenesis of HCCs has not been reported. METHODS: This retrospective study investigated ORAOV1 expression using immunohistochemistry performed on tissue microarray blocks obtained from 259 HCC patients with curative resection, between 2000 and 2006. We assessed the prognostic significance of ORAOV1 expression by Kaplan-Meier method with log-rank test and Cox proportional hazards model. Also, we performed invasion, migration, apoptosis, and cell cycle assays in HCC cell lines, and evaluated the tumorigenicity of HCC xenografts in nude mice, after knockdown of ORAOV1. RESULTS: High expression of ORAOV1 protein was observed in 80% of HCC tissues. The ORAOV1 high expression group showed shorter recurrence free survival (RFS) (p < 0.001) and shorter disease-specific survival (DSS) than the low expression group. It was an independent prognostic factor for predicting early recurrence [Odds ratio 2.74 (95% confidence interval (CI) 1.27-5.93), p = 0.01] as well as short RFS [hazard ratio 2.23 (95% CI 1.40-3.54), p = 0.001] and DSS [hazard ratio 2.30 (95% CI 1.27-4.17), p = 0.006]. Knockdown of ORAOV1 induced significant decreases in migration, invasion, and tumorigenicity of HCC cells in in-vitro model, and inhibited the growth of HCC xenografts in nude mice. CONCLUSION: We demonstrated unfavorable prognostic effect of ORAOV1 expression with supporting experimental data in HCC. ORAOV1 may be used as a biomarker for predicting HCC prognosis and is a potential candidate for targeted therapy.