Empirical comparison of deep learning models for fNIRS pain decoding.

Introduction: Pain assessment is extremely important in patients unable to communicate and it is often done by clinical judgement. However, assessing pain using observable indicators can be challenging for clinicians due to the subjective perceptions, individual differences in pain expression, and potential confounding factors. Therefore, the need for an objective pain assessment method that can assist medical practitioners. Functional near-infrared spectroscopy (fNIRS) has shown promising results to assess the neural function in response of nociception and pain. Previous studies have explored the use of machine learning with hand-crafted features in the assessment of pain. Methods: In this study, we aim to expand previous studies by exploring the use of deep learning models Convolutional Neural Network (CNN), Long Short-Term Memory (LSTM), and (CNN-LSTM) to automatically extract features from fNIRS data and by comparing these with classical machine learning models using hand-crafted features. Results: The results showed that the deep learning models exhibited favourable results in the identification of different types of pain in our experiment using only fNIRS input data. The combination of CNN and LSTM in a hybrid model (CNN-LSTM) exhibited the highest performance (accuracy = 91.2%) in our problem setting. Statistical analysis using one-way ANOVA with Tukey's (post-hoc) test performed on accuracies showed that the deep learning models significantly improved accuracy performance as compared to the baseline models. Discussion: Overall, deep learning models showed their potential to learn features automatically without relying on manually-extracted features and the CNN-LSTM model could be used as a possible method of assessment of pain in non-verbal patients. Future research is needed to evaluate the generalisation of this method of pain assessment on independent populations and in real-life scenarios.

Biomechanical stress distribution of medical inelastic fabrics with different porosity structures.

Clothing fit and pressure comfort play important role in clothing comfort, especially in medical body sculpting clothing (MBSC). In the present study, different body movements (forward bending, side bending, and twisting) were adopted to simulate and investigate the biomechanical stress distribution of the human body with three kinds of porosity inelastic MBSCs through the finite element analysis method. The elastic modulus of the investigated MBSCs was also measured by means of tensile testing. Analytical results showed that in the compression region during body movements, the investigated inelastic MBSCs endured less compression stress, and most of the stress was transmitted to the human body. Moreover, the stresses on the body surface were decreased with the porosity increasing. However, most of the von Mises stresses on the human body were in the desired pressure comfort range. Therefore, these results could provide potential information in the modification of MBSC for medical applications.

A Three-Dimensional Bioprinted Copolymer Scaffold with Biocompatibility and Structural Integrity for Potential Tissue Regeneration Applications.

The present study was to investigate the rheological property, printability, and cell viability of alginate−gelatin composed hydrogels as a potential cell-laden bioink for three-dimensional (3D) bioprinting applications. The 2 g of sodium alginate dissolved in 50 mL of phosphate buffered saline solution was mixed with different concentrations (1% (0.5 g), 2% (1 g), 3% (1.5 g), and 4% (2 g)) of gelatin, denoted as GBH-1, GBH-2, GBH-3, and GBH-4, respectively. The properties of the investigated hydrogels were characterized by contact angle goniometer, rheometer, and bioprinter. In addition, the hydrogel with a proper concentration was adopted as a cell-laden bioink to conduct cell viability testing (before and after bioprinting) using Live/Dead assay and immunofluorescence staining with a human corneal fibroblast cell line. The analytical results indicated that the GBH-2 hydrogel exhibited the lowest loss rate of contact angle (28%) and similar rheological performance as compared with other investigated hydrogels and the control group. Printability results also showed that the average wire diameter of the GBH-2 bioink (0.84 ± 0.02 mm (*** p < 0.001)) post-printing was similar to that of the control group (0.79 ± 0.05 mm). Moreover, a cell scaffold could be fabricated from the GBH-2 bioink and retained its shape integrity for 24 h post-printing. For bioprinting evaluation, it demonstrated that the GBH-2 bioink possessed well viability (>70%) of the human corneal fibroblast cell after seven days of printing under an ideal printing parameter combination (0.4 mm of inner diameter needle, 0.8 bar of printing pressure, and 25 °C of printing temperature). Therefore, the present study suggests that the GBH-2 hydrogel could be developed as a potential cell-laden bioink to print a cell scaffold with biocompatibility and structural integrity for soft tissues such as skin, cornea, nerve, and blood vessel regeneration applications.

2,3,5,4'-Tetrahydroxystilbene-2-O-ß-glucoside Attenuates Reactive Oxygen Species-Dependent Inflammation and Apoptosis in Porphyromonas gingivalis-Infected Brain Endothelial Cells.

We recently reported that the periodontopathic bacteria Porphyromonas gingivalis (P. gingivalis) initiates an inflammatory cascade that disrupts the balance of reactive oxygen species (ROS), resulting in apoptotic cell death in brain endothelial cells. An extract from Polygonum multiflorum Thunb., 2,3,5,4'-Tetrahydroxystilbene-2-O-ß-glucoside (THSG) has been well-reported to diminish the inflammation in many disease models. However, the effects of THSG in the area of the brain-oral axis is unknown. In this study, we examined the effects of THSG in P. gingivalis-stimulated inflammatory response and apoptotic cell death in brain endothelial cells. THSG treatment remarkably lessened the upregulation of IL-1ß and TNF-α proteins in bEnd.3 cells infected with P. gingivalis. Treatment of THSG further ameliorated brain endothelial cell death, including apoptosis caused by P. gingivalis. Moreover, the present study showed that the inhibitory effects on NF-κB p65 and antiapoptotic properties of THSG is through inhibiting the ROS pathway. Importantly, the ROS inhibitory potency of THSG is similar to a ROS scavenger N-Acetyl-L-Cysteine (NAC) and NADPH oxidase inhibitor apocynin. Furthermore, the protective effect of THSG from P. gingivalis infection was further confirmed in primary mouse brain endothelial cells. Taken together, this study indicates that THSG attenuates an ROS-dependent inflammatory response and cell apoptosis in P. gingivalis-infected brain endothelial cells. Our results also suggest that THSG could be a potential herbal medicine to prevent the risk of developing cerebrovascular diseases from infection of periodontal bacteria.

Profile of vitamin D receptor gene polymorphism TaqI in patients with periodontitis.

The present study aimed to assess the incidence of the vitamin D receptor (VDR) gene polymorphism TaqI in patients with periodontitis, and the potential association of this polymorphism with the severity of the disease. This was a case-controlled study, which included 162 adults divided into two groups as follows: Case group (81 patients diagnosed with periodontitis) and control group (81 patients without periodontitis). Venous blood was obtained from each sample from which DNA was extracted. The gene polymorphism was determined using restricted fragment length polymorphism-PCR and DNA sequencing to identify endonuclease restrictions in exon 9 (TaqI). The data were analyzed using an independent samples t-test. VDR gene polymorphisms were detected in periodontitis cases with TT (86.4%), Tt (12.4%) and tt (1.2%) genotypes. DNA sequencing confirmed a change in the sequence of the VDR gene nucleotides in patients with periodontitis. The data indicated that the severity of periodontal tissue damage may be influenced by changes in the nucleotide sequence.

Three-Dimensional Printing of a Hybrid Bioceramic and Biopolymer Porous Scaffold for Promoting Bone Regeneration Potential.

In this study, we proposed a three-dimensional (3D) printed porous (termed as 3DPP) scaffold composed of bioceramic (beta-tricalcium phosphate (ß-TCP)) and thermoreversible biopolymer (pluronic F-127 (PF127)) that may provide bone tissue ingrowth and loading support for bone defect treatment. The investigated scaffolds were printed in three different ranges of pore sizes for comparison (3DPP-1: 150−200 µm, 3DPP-2: 250−300 µm, and 3DPP-3: 300−350 µm). The material properties and biocompatibility of the 3DPP scaffolds were characterized using scanning electron microscopy, X-ray diffractometry, contact angle goniometry, compression testing, and cell viability assay. In addition, micro-computed tomography was applied to investigate bone regeneration behavior of the 3DPP scaffolds in the mini-pig model. Analytical results showed that the 3DPP scaffolds exhibited well-defined porosity, excellent microstructural interconnectivity, and acceptable wettability (θ < 90°). Among all groups, the 3DPP-1 possessed a significantly highest compressive force 273 ± 20.8 Kgf (* p < 0.05). In vitro experiment results also revealed good cell viability and cell attachment behavior in all 3DPP scaffolds. Furthermore, the 3DPP-3 scaffold showed a significantly higher percentage of bone formation volume than the 3DPP-1 scaffold at week 8 (* p < 0.05) and week 12 (* p < 0.05). Hence, the 3DPP scaffold composed of ß-TCP and F-127 is a promising candidate to promote bone tissue ingrowth into the porous scaffold with decent biocompatibility. This scaffold particularly fabricated with a pore size of around 350 µm (i.e., 3DPP-3 scaffold) can provide proper loading support and promote bone regeneration in bone defects when applied in dental and orthopedic fields.

An Innovative Customized Biomimetic Hydrogel for Drug Screening Application Potential: Biocompatibility and Cell Invasion Ability.

The ability of Pluronic F127 (PF127) conjugated with tetrapeptide Gly-Arg-Gly-Asp (GRGD) as a sequence of Arg-Gly-Asp (RGD) peptide to form the investigated potential hydrogel (hereafter referred to as 3DG bioformer (3BE)) to produce spheroid, biocompatibility, and cell invasion ability, was assessed in this study. The fibroblast cell line (NIH 3T3), osteoblast cell line (MG-63), and human breast cancer cell line (MCF-7) were cultured in the 3BE hydrogel and commercial product (Matrigel) for comparison. The morphology of spheroid formation was evaluated via optical microscopy. The cell viability was observed through cell counting Kit-8 assay, and cell invasion was investigated via Boyden chamber assay. Analytical results indicated that 3BE exhibited lower spheroid formation than Matrigel. However, the 3BE appeared biocompatible to NIH 3T3, MG-63, and MCF-7 cells. Moreover, cell invasion ability and cell survival rate after invasion through the 3BE was displayed to be comparable to Matrigel. Thus, these findings demonstrate that the 3BE hydrogel has a great potential as an alternative to a three-dimensional cell culture for drug screening applications.

A Promising Potential of Brown Algae Sargassum polycystum as Irreversible Hydrocolloid Impression Material.

This study aimed to investigate the potential use of brown algae Sargassum polycystum as irreversible hydrocolloid (alginate) impression material. Potassium alginate extracted from Sargassum polycystum was prepared in three different compositions (14%, 15%, and 16%) and mixed with other standard components to form an alginate impression material. Prior to that, the purity of potassium alginate was quantified with Fourier Transform Infrared Spectroscopy (FTIR) analysis. As a control material, the alginate impression material from a commercially available product was used. All alginate impression materials were then applied to a die stone model. Dimensional accuracy was measured by calculating the mesiodistal width of incisors in the generated dental cast using a digital caliper 0.01 accuracy (five replications). In addition, to evaluate the dimensional stability, the impression results were poured at four different periods (immediately, 5 min, 10 min, and 15 min). An independent t-test was performed to compare the measurement results with p < 0.05 considered significant. Analytical results confirm that the impression material containing 15% potassium alginate gives the best dimensional accuracy similar to control (p > 0.05). Meanwhile, the optimal dimensional stability was produced in the impression material containing 16% potassium alginate. Our study suggested that brown algae Sargassum polycystum has a promising potential to be used as an alginate impression material in clinical application.

Biomimetic Ceramic Composite: Characterization, Cell Response, and In Vivo Biocompatibility.

The present study aimed to synthesize biphasic calcium phosphate ceramics (CaPs) composed of ß-tricalcium phosphate (ß-TCP) and hydroxyapatite (HAp) from the propagated Scleractinian coral and dicalcium phosphate anhydrous using a solid-state reaction followed by heat treatment at a temperature of 1100 °C for 1 h to 7 days. The as-prepared coral and coral-derived biphasic CaPs samples were characterized through scanning electron microscopy, X-ray diffractometry, Fourier transform infrared spectroscopy, and Raman spectroscopy. The cell response of the biphasic CaPs was evaluated by in vitro cytotoxicity assessment using mouse fibroblast (L929) cells. The bilateral femoral defect rabbit model was used to assess the early local reaction of the coral-derived biphasic CaPs bone graft on tissue. The results confirmed that the co-existence of ß-TCP and HAp was formed at 1100 °C for 1 h. The ratio of HA/ß-TCP increased as the heat-treatment time increased. The coral-derived biphasic CaPs comprising 61% HAp and 39% ß-TCP (defined as HT-3) were not cytotoxic. Furthermore, no significant differences in local tissue reaction were observed between the HT-3 sample and autogenous bone. Therefore, the synthesized coral-derived biphasic CaPs is a candidate for bone grafting due to its good biocompatibility.

Porphyromonas gingivalis Induces Proinflammatory Cytokine Expression Leading to Apoptotic Death through the Oxidative Stress/NF-κB Pathway in Brain Endothelial Cells.

Porphyromonas gingivalis, a periodontal pathogen, has been proposed to cause blood vessel injury leading to cerebrovascular diseases such as stroke. Brain endothelial cells compose the blood-brain barrier that protects homeostasis of the central nervous system. However, whether P. gingivalis causes the death of endothelial cells and the underlying mechanisms remain unclear. This study aimed to investigate the impact and regulatory mechanisms of P. gingivalis infection in brain endothelial cells. We used bEnd.3 cells and primary mouse endothelial cells to assess the effects of P. gingivalis on endothelial cells. Our results showed that infection with live P. gingivalis, unlike heat-killed P. gingivalis, triggers brain endothelial cell death by inducing cell apoptosis. Moreover, P. gingivalis infection increased intracellular reactive oxygen species (ROS) production, activated NF-κB, and up-regulated the expression of IL-1ß and TNF-α. Furthermore, N-acetyl-L-cysteine (NAC), a most frequently used antioxidant, treatment significantly reduced P. gingivalis-induced cell apoptosis and brain endothelial cell death. The enhancement of ROS production, NF-κB p65 activation, and proinflammatory cytokine expression was also attenuated by NAC treatment. The impact of P. gingivalis on brain endothelial cells was also confirmed using adult primary mouse brain endothelial cells (MBECs). In summary, our results showed that P. gingivalis up-regulates IL-1ß and TNF-α protein expression, which consequently causes cell death of brain endothelial cells through the ROS/NF-κB pathway. Our results, together with the results of previous case-control studies and epidemiologic reports, strongly support the hypothesis that periodontal infection increases the risk of developing cerebrovascular disease.

Immunomodulatory activity seen as a result of photobiomodulation therapy in stimulated primary human fibroblasts.

OBJECTIVE: Oral biofilms burden host responses by induction of inflammatory mediators, exacerbating periodontal inflammation. Photobiomodulation Therapy (PBMT) has been shown to decrease levels of pro-inflammatory cytokines and chemokines. However, optimal wavelengths and exposure doses have not been established. This study investigated the effects of PBMT on human periodontal ligament fibroblasts (hPDLFs) stimulated with inflammatory mediators (LPS, TNF-α, and IL-1ß). METHODS: Cytotoxic effects of laser wavelengths 660 nm and 810 nm were assessed by measuring their effects on cellular dehydrogenase activity. The study was expanded to include 980 nm, 660 nm + 810 nm, and 810 nm + 980 nm. P.g. LPS, TNF-α, and/or IL-1ß were added one hour before irradiation, then exposed to laser irradiation to determine the most appropriate stimulus. The levels of INF-γ, IL-6, IL-8, IL-17A/F, and MCP-1 production in stimulated hPDLFs were measured and analyzed. RESULTS: P.g. LPS was a poor stimulus for hPDLFs, while TNF-α and IL-1ß significantly elevated the analytes. The 660 nm laser treatment induced pro-inflammatory cytokines when stimulated, while 810 nm exhibited significant suppression. IL-1ß was the stimulus of choice and the 810 nm wavelength alone exhibited anti-inflammatory effects for all analytes except IL-8, while the 810 nm in combination with 660 nm and/or 980 nm exhibited effects similar to 810 nm alone. CONCLUSIONS: The downregulation of inflammatory mediators by the combination or individual treatment with 810 nm wavelength shows promise for the management of periodontal inflammation. PBMT may lead to the development of a novel approach in the management of periodontal disease.

Resin cement removal from titanium dental implant surface using a novel side-firing laser fiber and Er,Cr:YSGG irradiation.

PURPOSE: evaluate the influence of an erbium, chromium: yttrium, scandium, gallium, garnet (Er,Cr:YSGG) laser using multiple tip types, on the removal of retained cement on a titanium implant surface. METHODS: Nine titanium dental implants were coated with a non-eugenol resin composite implant cement. An Er,Cr:YSGG device at a wavelength of 2,780 nm was fitted sequentially with three laser fiber tips: (1) 6 mm long, 600 µm diameter end-firing, quartz; (2) 9 mm long, Radial-Firing Perio Tip, 500 µm diameter, quartz; and (3) 18 mm long Side-Firing Tip, 800 µm x 300 µm, sapphire. Irradiation on the implant surfaces was performed in short pulse mode (140 µsec pulse duration) with output power of 1.5 W, 50% water, 40% air, and either: (1) 15 Hz, 100 mJ/pulse; (2) 30 Hz, 50 mJ/pulse; or (3) 40 Hz, 37.5 mJ/pulse. Three trials each were completed for each of three different fiber tip types for a total of 27 trials (three trials for each of the nine groups). RESULTS: All samples in Groups 1-6 demonstrated complete removal of cement from the implant surface. SEM inspection revealed a high degree of melting of the resin composite cement on the implant surface in all samples treated with 100 mJ/pulse (Groups 1, 2, 3). At 50 mJ/pulse (30 Hz), the results of the end-firing and side-firing tips improved remarkably, with clean implant surfaces and comparatively little melting. The side-firing fiber at 50 mJ/pulse and 30 Hz provided the best overall combination of cement removal and least amount of residual melted material on the implant surface. Based on the limitations of this study, the most appropriate method of removing residual cement from a TiUnite coated titanium implant surface is by using an Er,Cr:YSGG laser device fitted with a side-firing laser tip. Laser parameters of 50 mJ/pulse and 30 Hz (1.5W average power), with at least 50% water and 40% air in the aerosolized water spray are ideal. CLINICAL SIGNIFICANCE: As the presence of peri-implantitis continues to increase in numbers and severity, it is imperative to have a predictable treatment protocol to address the large number of ailing and failing implant cases. This study offers one solution to the problem of peri-implantitis, especially if caused by retained cement. Optimal laser settings are proposed for surface decontamination and treatment.

Guidelines for the Biopsy of Oral Mucosal Lesions Using a Laser.

Dental lasers are increasingly being used to harvest soft-tissue biopsies. Lasers generally offer numerous benefits compared with conventional treatment modalities of tissue collection, including providing less trauma, uncomplicated healing, and faster recovery. Also, common problems seen with other novel methods of sample collection are avoided with the use of dental lasers. However, because of a laser's thermal effects, incisional margins may not always be as sufficiently defined as necessary for histopathologic analysis. Deficiencies associated with the use of a dental laser to collect a proper sample are related mostly to either insufficient tissue for diagnosis or other tissue artifacts, specifically thermal artifacts. This article, therefore, is aimed at assisting clinicians in enhancing biopsy technique when using a laser.

Highly Expressed FOXF1 Inhibit Non-Small-Cell Lung Cancer Growth via Inducing Tumor Suppressor and G1-Phase Cell-Cycle Arrest.

Cancer pathogenesis results from genetic alteration-induced high or low transcriptional programs, which become highly dependent on regulators of gene expression. However, their role in progressive regulation of non-small-cell lung cancer (NSCLC) and how these dependencies may offer opportunities for novel therapeutic options remain to be understood. Previously, we identified forkhead box F1 (FOXF1) as a reprogramming mediator which leads to stemnesss when mesenchymal stem cells fuse with lung cancer cells, and we now examine its effect on lung cancer through establishing lowly and highly expressing FOXF1 NSCLC engineered cell lines. Higher expression of FOXF1 was enabled in cell lines through lentiviral transduction, and their viability, proliferation, and anchorage-dependent growth was assessed. Flow cytometry and Western blot were used to analyze cellular percentage in cell-cycle phases and levels of cellular cyclins, respectively. In mice, tumorigenic behavior of FOXF1 was investigated. We found that FOXF1 was downregulated in lung cancer tissues and cancer cell lines. Cell proliferation and ability of migration, anchorage-independent growth, and transformation were inhibited in H441-FOXF1H and H1299-FOXF1H, with upregulated tumor suppressor p21 and suppressed cellular cyclins, leading to cell-cycle arrest at the gap 1 (G1) phase. H441-FOXF1H and H1299-FOXF1H injected mice showed reduced tumor size. Conclusively, highly expressing FOXF1 inhibited NSCLC growth via activating tumor suppressor p21 and G1 cell-cycle arrest, thus offering a potentially novel therapeutic strategy for lung cancer.

Stereolithographic Surgical Guide with a Combination of Tooth and Bone Support: Accuracy of Guided Implant Surgery in Distal Extension Situation.

A distal free-end situation could result in insufficient stability of the surgical guide, and could reduce accuracy of the static guided implant surgery (sGIS). The purpose of this study was to investigate the accuracy of sGIS using a combination tooth-and-bone supported stereolithographic (SLA) surgical guide in distal extension situation. Thirty dentists, each placed three implants at the Federal Dentaire Internationale (FDI) teeth positions #46, #47 (a distal extension situation), and #36 (a single tooth gap) via the surgical guide on a model fixed to a manikin. Pre- and post-operative computed tomography (CT) images of the models were superimposed, and the positional and angular deviations of the implants were measured with metrology software. An analysis of variance (ANOVA) test was performed to evaluate the intergroup differences. No significant differences were found for all the positional and angular deviations among the three implant sites, except the bucco-lingual deviation at the implant platform in the #47 position (0.43 ± 0.19 mm) that was significantly larger than the #46 (0.21 ± 0.14 mm) and #36 (0.24 ± 0.25 mm) positions (p < 0.0001). Within the limits of this study, we conclude that, in distal extension situation of missing mandibular molars, adding a bone-supported strut in the distal part of the surgical guide can be beneficial to the accuracy of the sGIS.

Platelet-Rich Fibrin Facilitates One-Stage Cartilage Repair by Promoting Chondrocytes Viability, Migration, and Matrix Synthesis.

The main aim of this study is to develop a one-stage method to combine platelet-rich fibrin (PRF) and autologous cartilage autografts for porcine articular cartilage repair. The porcine chondrocytes were treated with different concentrations of PRF-conditioned media and were evaluated for their cell viability and extracellular glycosaminoglycan (GAG) synthesis during six day cultivation. The chemotactic effects of PRF on chondrocytes on undigested cartilage autografts were revealed in explant cultures. For the in vivo part, porcine chondral defects were created at the medial femoral condyles of which were (1) left untreated, (2) implanted with PRF combined with hand-diced cartilage grafts, or (3) implanted with PRF combined with device-diced cartilage grafts. After six months, gross grades, histological, and immunohistochemical analyses were compared. The results showed that PRF promotes the viability and GAG expression of the cultured chondrocytes. Additionally, the PRF-conditioned media induce significant cellular migration and outgrowth of chondrocytes from undigested cartilage grafts. In the in vivo study, gross grading and histological scores showed significantly better outcomes in the treatment groups as compared with controls. Moreover, both treatment groups showed significantly more type II collagen staining and minimal type I collagen staining as compared with controls, indicating more hyaline-like cartilage and less fibrous tissue. In conclusion, PRF enhances the viability, differentiation, and migration of chondrocytes, thus, showing an appealing capacity for cartilage repair. The data altogether provide evidences to confirm the feasibility of a one-stage, culture-free method of combining PRF and cartilage autografts for repairing articular cartilage defects. From translational standpoints, these advantages benefit clinical applications by simplifying and potentiating the efficacy of cartilage autograft transplants.

Application of a Promising Bone Graft Substitute in Bone Tissue Regeneration: Characterization, Biocompatibility, and In Vivo Animal Study.

The purpose of the present study was to investigate the effect of local hydroxyapatite (HA) combined with extracted sea cucumber (Stichopus hermanni) collagen as a promising bone graft substitute on bone remodeling. Fourier-transform infrared spectroscopy, X-ray diffractometry, transmission electron microscopy, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and Sprague-Dawley rat model were used to characterize the microstructure, in vitro cytotoxicity, and in vivo bone-healing properties of the investigated biocomposite material. Analytical results found that the hydrothermal reaction-synthesized local HA had a hexagonal close-packed structure. The addition of extracted S. hermanni collagen did not influence the microstructure and functional groups of the local HA. Moreover, the MTT assay indicated that the investigated biocomposite material possessed a good in vitro biocompatibility. The in vivo animal study also revealed that the investigated biocomposite material exhibited the highest number of osteoblasts after 14 days of healing. Therefore, the results demonstrate that the local HA combined with extracted S. hermanni collagen could potentially enhance osteoblast formation in promoting bone healing and regeneration.

Establishing cleft services in developing countries: Complications of cleft lip and palate surgery in rural areas of Indonesia.

BACKGROUND: Cleft treatment is frequently performed in Indonesia, mostly in charity missions, but without a postoperative protocol it is difficult to establish the risks and complications of cleft treatment. The present study was designed to give an overview of current cleft lip and palate treatment strategies in Indonesia and to assess the complication rates during and after surgery. METHODS: This prospective study evaluated anesthetic, intraoperative surgical, and short-term postoperative complications in patients undergoing primary, secondary, or corrective surgery for cleft lip and palate deformities. The population consisted of 98 non-syndromic cleft patients. The main anesthetic complication that occurred during general anesthesia was high blood pressure, whereas the main intraoperative surgical complication was excessive bleeding and the main early postoperative complication was extremely poor wound hygiene. RESULTS: In this study, there were no cases of perioperative or postoperative mortality. However, in 23 (23.4%) of the 98 operations performed, at least one perioperative complication related to anesthesia occurred. The intraoperative and early postoperative complications following cleft lip and/or palate were assessed. There was a significant difference in the complication rate between procedure types (χ2=0.02; P<0.05). However, no relationship was found between perioperative complications related to anesthesia and the occurrence of postoperative complications (χ2=1.00; P>0.05). Nonetheless, a significant difference was found between procedure types regarding perioperative complications and the occurrence of postoperative complications (χ2=0.031; P<0.05). CONCLUSIONS: Further evaluation of these outcomes would help direct patient management toward decreasing the complication rate.

A Machine Learning Approach for the Identification of a Biomarker of Human Pain using fNIRS.

Pain is a highly unpleasant sensory and emotional experience, and no objective diagnosis test exists to assess it. In clinical practice there are two main methods for the estimation of pain, a patient's self-report and clinical judgement. However, these methods are highly subjective and the need of biomarkers to measure pain is important to improve pain management, reduce risk factors, and contribute to a more objective, valid, and reliable diagnosis. Therefore, in this study we propose the use of functional near-infrared spectroscopy (fNIRS) and machine learning for the identification of a possible biomarker of pain. We collected pain information from 18 volunteers using the thermal test of the quantitative sensory testing (QST) protocol, according to temperature level (cold and hot) and pain intensity (low and high). Feature extraction was completed in three different domains (time, frequency, and wavelet), and a total of 69 features were obtained. Feature selection was carried out according to three criteria, information gain (IG), joint mutual information (JMI), and Chi-squared (χ2). The significance of each feature ranking was evaluated using three learning models separately, linear discriminant analysis (LDA), the K-nearest neighbour (K-NN) and support vector machines (SVM) using the linear and Gaussian and polynomial kernels. The results showed that the Gaussian SVM presented the highest accuracy (94.17%) using only 25 features to identify the four types of pain in our database. In addition, we propose the use of the top 13 features according to the JMI criteria, which exhibited an accuracy of 89.44%, as promising biomarker of pain. This study contributes to the idea of developing an objective assessment of pain and proposes a potential biomarker of human pain using fNIRS.

The potential of the three-dimensional printed titanium mesh implant for cranioplasty surgery applications: Biomechanical behaviors and surface properties.

The aim of the present study was to investigate the biomechanical behaviors of the pre-shaped titanium (PS-Ti) cranial mesh implants with different pore structures and thicknesses as well as the surface characteristics of the three-dimensional printed Ti (3DP-Ti) cranial mesh implant. The biomechanical behaviors of the PS-Ti cranial mesh implants with different pore structures (square, circular and triangular) and thicknesses (0.2, 0.6 and 1 mm) were simulated using finite element analysis. Surface properties of the 3DP-Ti cranial mesh implant were performed by means of scanning electron microscopy, X-ray diffraction and static contact angle goniometer. It was found that the stress distribution and peak Von Mises stress of the PS-Ti cranial mesh implants significantly decreased at the thickness of 1 mm. The PS-Ti mesh implant with the circular pore structure created a relatively lower Von Mises stress on the bone defect area as compared to the PS-Ti mesh implant with the triangular pore structure and square pore structure. Moreover, the spherical-like Ti particle structures were formed on the surface of the 3DP-Ti cranial mesh implant. The microstructure of the 3DP-Ti mesh implant was composed of α and rutile-TiO2 phases. For wettability evaluation, the 3DP-Ti cranial mesh implant possessed a good hydrophilicity surface. Therefore, the 3DP-Ti cranial mesh implant with the thickness of 1 mm and circular pore structure is a promising biomaterial for cranioplasty surgery applications.