bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pneumococcal Neuraminidases Increase Platelet Killing by Pneumolysin
Authors: Fritsch Kristin J. , Krüger Laura , Handtke Stefan , Kohler Thomas P. , Ozhiganova Arina , Jahn Kristin , Wesche Jan , Greinacher Andreas , Hammerschmidt Sven 
Published: July 2024

Background Platelets prevent extravasation of capillary fluids into the pulmonary interstitial tissue by sealing gaps in inflamed endothelium. This reduces respiratory distress associated with pneumonia. Streptococcus pneumoniae is the leading cause of severe community-acquired pneumonia. Pneumococci produce pneumolysin (PLY), which forms pores in membranes of eukaryotic cells including platelets. Additionally, pneumococci express neuraminidases, which cleave sialic acid residues from eukaryotic glycoproteins. In this study, we investigated the effect of desialylation on PLY binding and pore formation on platelets.
Materials and Methods We incubated human platelets with purified neuraminidases and PLY, or nonencapsulated S. pneumoniae D39/TIGR4 and isogenic mutants deficient in PLY and/or NanA. We assessed platelet desialylation, PLY binding, and pore formation by flow cytometry. We also analyzed the inhibitory potential of therapeutic immunoglobulin G preparations (IVIG [intravenous immunoglobulin]).
Results Wild-type pneumococci cause desialylation of platelet glycoproteins by neuraminidases, which is reduced by 90 to 100% in NanA-deficient mutants. NanC, cleaving only α2,3-linked sialic acid, induced platelet desialylation. PLY binding to platelets then x2doubled (p = 0.0166) and pore formation tripled (p = 0.0373). A neuraminidase cleaving α2,3-, α2,6-, and α2,8-linked sialic acid like NanA was even more efficient. Addition of polyvalent IVIG (5 mg/mL) decreased platelet desialylation induced by NanC up to 90% (p = 0.263) and reduced pore formation >95% (p < 0.0001) when incubated with pneumococci.
Conclusion Neuraminidases are key virulence factors of pneumococci and desialylate platelet glycoproteins, thereby unmasking PLY-binding sites. This enhances binding of PLY and pore formation showing that pneumococcal neuraminidases and PLY act in concert to kill platelets. However, human polyvalent immunoglobulin G preparations are promising agents for therapeutic intervention during severe pneumococcal pneumonia.
Cross-Cultural Adaptation of The Indonesian Version Functional Assessment of Denture Instrument as a Measuring Tool for Complete Denture Functional Quality
Authors: Rambey Arrad Ibrahim , Ariani Nina , Kusdhany Lindawati Soetanto 
Published: July 2024

Abstract
Objective Making good quality dentures is necessary to avoid patients' discomfort when adapting to new dentures. Several studies regarding the assessment of the quality of dentures have been carried out in many other countries, such as using the Functional Assessment of Dentures (FAD) by Anastassiadou. However, studies have yet to be conducted in Indonesia. This study aims to obtain a valid and reliable instrument to measure the quality of complete dentures (CDs). This study also aims to find out whether the functional quality of a CD measured with the Indonesian version of the FAD Instrument (PFGT) can affect patient satisfaction in receiving CD treatment (measured with Indonesian version of Patient's Denture Assessment [PDA-Id]) and to find contributing factors to the functional quality of a CD.
Materials and Methods The study was conducted in two stages. The first stage was a qualitative study using cross-cultural adaptation methods and focus group discussions with experts. The second stage was a quantitative test with a total of 40 subjects for statistical analysis in the form of a kappa test, test–retest, Kuder–Richardson (KR) 20, and a correlation test between PDA-Id and PFG. Multivariate analysis was done to analyze contributing factors to the functional quality of CD.
Results The final instrument was obtained from the qualitative test, which was tested for content and face validation. The interrater kappa test result of 0.828 shows an almost perfect agreement. The results of the intrarater test–retest (0.564; p > 0.05; intraclass correlation coefficient 0.889) showed excellent instrument stability. The results of the internal consistency test with Kuder–Richardson 20 (1.08; KR > 1) showed good internal consistency. The correlation test results between PFGT and PDA-Id (0.044; p < 0.05) showed a positive correlation. Multivariate analysis showed a relationship between the quality of the CD, the length of time the CD was used, and the patient's satisfaction with CD treatment.
Conclusion The PFGT instrument is considered a valid and reliable tool to measure the functional quality of a denture that can distinguish between good and bad quality.
In vitro Analysis of DSPP and BSP Expression: Comparing the Odontogenic Influence of Bio-C Repair and Biodentine in hDPSCs
Authors: Wairooy Valeria Widita , Bagio Dini Asrianti , Margono Anggraini , Amelia Ingrid 
Published: July 2024

Abstract
Objectives This study compared the ability of BIO-C Repair (BC) and Biodentine (BD) in relation to odontogenic differentiation by evaluating the dentin sialophosphoprotein (DSPP) and bone sialoprotein (BSP) expression and mineral deposition of human dental pulp stem cells (hDPSCs).
Materials and Methods BC and BD were pulverized and sterilized (ISO 10993-5:2009). The hDPSCs were the result of primary cultures that were 80% confluent (having gone through the stem cell marker tests CD90 98%, CD105 99.7%, CD73 94%, and LinNeg 0.5%) and reached P2–3 by means of serum starvation for 24 hours. This study involved seven groups, in which the hDPSCs were cultured on osteogenic media with the addition of either BD (Septodont, United States) at concentrations of 1:1, 1:2, or 1:5; BC (Angelus, Brazil) at concentrations of 1:1, 1:2, or 1:5; or the negative control (Dulbecco's modified eagle medium + osteogenic media). The hDPSC differentiation was determined via enzyme-linked immunosorbent assays of DSPP and BSP expression performed on days 7 and 14 and alizarin red staining performed on day 21.
Statistical Analysis The data were analyzed using a one-way analysis of variance, followed by Tamhane's post hoc test, to compare the differences between groups. The t-test dependent was also used to identify differences between groups.
Results BC and BD at 1:1 concentration, there was a statistically significant difference in DSPP and BSP expression. However, at concentrations of 1:2 and 1:5, there was no significant difference observed in either duration of observation (p > 0.05). The highest DSPP and BSP concentrations after 7 and 14 days of observation were observed with BD and BC at 1:5 concentration (6.6–6.71 and 13.20–13.47 ng/mL).
Conclusion The study shows that BC is as effective as BD in enhancing DSPP and BSP expression and mineral deposition in hDPSCs. The 1:5 concentration of BC showed the highest levels of DSPP and BSP expression and mineral deposition.
The Effects of MMP3 (rs679620) and VDR (rs731236) Gene Polymorphisms on Dental Caries: A Pilot Study
Authors: Özmen Seda , Atalı Pınar Yılmaz , Ağralı Ömer Birkan , Aslan Beste Tacal , Yılmaz Özlem Özge , Polat Tolga , Ulucan Korkut 
Published: July 2024

Abstract
Objective Caries formation is a process affected by various factors. Studies have shown that genetic factors also play a role in caries formation. The aim of our study is to examine the effects of matrix metalloproteinase (MMP)3 (rs679620) and vitamin D receptor (VDR) (rs731236) gene polymorphisms on caries formation.
Materials and Methods Following routine oral examinations in individuals aged between 20 and 44 years, the diagnosis was made according to the decayed, missing, and filled teeth (DMFT) index, and experimental group was defined as “high caries risk” (DMFT ≥ 14, n = 28), and the control group as “no caries” (DMFT = 0, n = 28). Plaque index and bleeding on probing were measured from participants with a detailed anamnesis. Periodontally healthy individuals with less than 10% bleeding on probing were included in the study (n = 56). After DNA isolation from blood samples taken from the participants, the genotyping of MMP3 (rs679620) and VDR (rs731236) gene polymorphisms were determined using the real-time polymerase chain reaction technique.
Statistical Analysis Data were analyzed with IBM SPSS V23.0. Data distribution was evaluated with Kolmogorov–Smirnov's test. Pearson's chi-square test was used to compare categorical data according to groups. The results were evaluated using a significance level of p < 0.05.
Results Regarding MMP3 and VDR gene polymorphisms, there was a statistically significant difference between the groups in terms of MMP3 (rs679620) (p < 0.001). There was no statistically significant difference between the VDR (rs731236) genotype distributions of the groups (p = 0.659).
Conclusion Within the limits of this study, MMP3 rs679620 gene polymorphism may have an effect on caries formation.
Effectiveness of Sectioning Method and Filling Materials on Roughness and Cell Attachments in Root Resection Procedure
Authors: Ashi Tarek , Kharouf Naji , Etienne Olivier , Cournault Bérangère , Klienkoff Pierre , Gribova Varvara , Haikel Youssef 
Published: July 2024

Abstract
Objectives The purpose of the present study was to investigate the created roughness and cell attachment of intact teeth (C), obturated teeth with bioceramic (BR), or epoxy resin (AH) after root resection using piezoelectric ultrasonic and carbide bur.
Materials and Methods Three groups of first mandibular premolars were used in the present study: control group (without any preparation or obturation) (C); second group was obturated with an epoxy resin sealer (AH, AH Plus Jet); and finally, the third one was obturated with a bioceramic sealer (BR, BioRoot RCS). All teeth were incubated for 4 months at 37°C. After that, the samples were sectioned using tungsten carbide bur or piezoelectric ultrasonic. Roughness and then cell attachment of periodontal ligament cells on the sectioned surfaces were investigated by profilometer and confocal microscope, respectively.
Statistical Analysis Data were statistically analyzed using one-way analysis of variance.
Results After root resection, no significant difference was found between the roughness among the three groups sectioned using the piezoelectric technique (p > 0.05). In contrast, concerning the sectioned samples by burs, C demonstrated a rougher surface compared with BR (p < 0.05). There was a significant higher cell attachment in BR compared with AH in the piezoelectric groups (p = 0.047), while no statistically significant difference was found between the groups sectioned with bur (p > 0.05).
Conclusion Dentists are now focused on the use of calcium silicate-based sealers due to their bioactivity. The present study advises dentists to use bioceramic sealer which could improve the dentin characteristics which ameliorate the cell attachment.
Sonographic Assessment of Isthmocele and Its Obstetric Complications in Subsequent Pregnancies: A Pictorial Review
Authors: Agarwal Prateek , Agarwal Rajesh Kumar , Purohit Arushi 
Published: July 2024

AbstractCesarean scar defect represents a significant pathology attributed to the rising prevalence of cesarean deliveries. While not commonplace, these lesions can give rise to severe obstetric consequences during subsequent pregnancies. Given the potential complications, it is advisable to screen for uterine niches using transvaginal ultrasound (TVUS) or contrast-enhanced TVUS for individuals planning to conceive. Surgical repair and correction of these lesions can be crucial in averting obstetric and perinatal complications in future pregnancies. Furthermore, timely sonographic evaluation and reporting of isthmocele-related obstetric complications can help avoid serious issues.
The influence of mentorship and working environments on foreign language teachers’ research motivation in China
Authors: Li Yanping , Zhang Lawrence Jun , Mohamed Naashia 
Published: July 2024

AbstractTeachers at Higher Education (HE) institutions are expected to do research. However, the level of motivation to engage in research varies with various institutional factors affecting teachers’ research motivation. Previous research has shown the need to better understand these factors to facilitate teachers’ research motivation. This mixed methods study with 536 English as a foreign language (EFL) teacher participants from Chinese universities investigates the relationship between mentorship, working environment and teachers’ research motivation. Our analysis of the questionnaire data using Structural Equation Modelling (SEM) shows the significant influence of working environments on teachers’ research motivation. Qualitative data from semi-structured interviews and diaries were thematically analysed to reveal that the examined factors have different impacts on teachers’ research motivation on the basis of different university types. Both mentorship and working environments had an influence on teachers’ research motivation. Teachers from “Project 985” and “Project 211” universities had a more supportive working environment than those teachers at ordinary/regular universities who appeared to have insufficient mentorship, poor working environments, inadequate time support, and deficient opportunities to attend academic conferences that affected these teachers’ research motivation negatively. The implications of our study are that university administrators and policymakers could develop practical mentorship programmes with effective assessment measurements of the mentoring process and stipulate relevant policies to provide conducive working environments, especially for teachers from ordinary/regular universities, to enhance teachers’ research motivation and improve their research productivity.
Novel insights from financial analysis of the failure to commercialise plazomicin: Implications for the antibiotic investment ecosystem
Authors: Wells Nadya , Nguyen Vinh-Kim , Harbarth Stephan 
Published: July 2024

AbstractThe need for novel antibiotics to combat emerging multi-drug resistant bacterial strains is widely acknowledged. The development of new therapeutic agents relies on small and medium-sized biotechnology enterprises (SMEs), representing 75% of the late-stage pipeline. However, most SME sponsors of an antibacterial approved by the FDA since 2010 have gone bankrupt, or exited at a loss, below investment cost. Uncovering financial flows related to the development and commercialisation of a single drug is complex and typically untransparent. There is therefore a lack of empirical research on the financial vulnerabilities of these critical SMEs. The development of plazomicin by Achaogen (2004–2019) entailed financial disclosures as a public company enabling application of financial analysis methods to: determine quantum and timing of public and private investments; quantify development costs; and provide a deeper understanding of the role of capital market dependency in exacerbating pipeline fragility. Achaogen’s widely cited bankruptcy, and plazomicin’s commercialisation failure, created a perception that novel antibiotics have zero market value, causing investors to question the SME developer business model. Our analysis of Achaogen’s inability to fund commercialisation suggests three key implications for the antibiotic investment ecosystem: (1) novel antibiotics with narrow approval for small patient populations affected by severe resistant infections cannot be successfully commercialised in the current US antibiotic market; (2) SMEs need incentive payments structured to enable them to survive the commercialisation cashflow drought, and (3) these changes are necessary to restore industry and financial investor confidence in the antibiotic SME development model. Achaogen’s demise demonstrates that proposals to incentivise innovation, e.g. by providing one-off payments at registration, may be insufficient to ensure access to novel antibiotics developed by SMEs. In plazomicin’s case, moreover, US government biosecurity investments have not resulted in access, as the Indian and Chinese companies which bought post-bankruptcy rights have not widely commercialised the drug. This study is timely as new market-based incentives are currently being proposed by the US, EU, Canada and Japan. In order to make further government funding effective, ensuring access, not only innovation, these must support sustainable financial models for the SMEs critical to novel antibiotic development.
Structural phase transition, relaxor behavior, and ultra-low strain hysteresis in BaTiO3 ceramics modified by BiYO3
Authors: Ma Cuiying , Liang Ruinan , Liu Jia , Shang Furong , Cheng Zhimin , Du Huiling 
Published: July 2024

Abstract
In this study, the structural properties, phase transition, relaxor behavior, and strain properties of (1−x)BaTiO3‒xBiYO3 (x= 0.02‒0.15 mol) ceramics were investigated. The room temperature x-ray diffraction and Raman spectroscopy results reveal that (1−x)BaTiO3‒xBiYO3 ceramics undergo phase transition from tetragonal to pseudo-cubic structure with x increasing. The curves of dielectric constant and loss tangent as a function of temperature and frequency show that the dielectric constant was changing from being dependent on temperature to being independent of it upon increasing BiYO3 amount, which is induced obvious dielectric relaxation behavior. Slimmer polarization–electric field (P–E) loops and lower remnant polarization (Pr
) were observed for samples with x ⩾ 0.08. The transition between the ferroelectric and relaxor states leads to the narrow strain–electric field (S–E) loops, which exhibit a high electric field-induced strain of 0.192% and an ultra-low strain hysteresis of 10.4% at an electric field of 70 kV cm−1 for x= 0.04. This excellent performance indicates that 0.96BaTiO3‒0.04BiYO3 ceramic may be promising lead-free materials for high-precision displacement actuators applications.
Design of FDM fabricated poly-lactic acid parts with forced-air cooling speed as the new control parameter to tune its shape memory effect
Authors: Lee Chun-Ying , Liu Chung-Yin , Hadas Zdenek , Stachiv Ivo 
Published: July 2024

Abstract
Poly lactic acid (PLA) as one of the shape memory polymers has extensively been used as the material in the 3D printing by fused deposition modeling process. In this study, we introduced the forced-air cooling speed as new control parameter in the fabrication process. A commercial material extrusion printer was retrofitted with a control module of forced-air cooling system. The shape memory effects of the PLA printed in different cooling speeds from 0–5 m s−1 were first measured by submerging the printed coupon specimens into water bath at recovery temperature. It is found that the changes in dimensions were mainly anisotropic and dependent of the raster angle in printing, in addition to the controlled cooling speed. The shape memory strains were roughly in linear trend with the magnitude of cooling air speed. In other words, the shape memory effect of the PLA can be easily controlled by the cooling air speed in fabrication. X-ray diffraction measurement on the specimens before and after recovery treatment confirmed the shape memory effect was related to the partial crystallization of molecular structure. Moreover, the different cooling air speeds also induced different thermal stresses in the printed specimens which manifest its important role in the total shape memory strain. Finally, the proposed theoretical beam formulation for the recovery bending deflection was shown to have good prediction accuracy comparing with experimental measurements.
Auditory nerve fiber excitability for alternative electrode placement in the obstructed human cochlea: electrode insertion in scala vestibuli versus scala tympani
Authors: Fellner Andreas , Wenger Cornelia , Heshmat Amirreza , Rattay Frank 
Published: July 2024

Abstract

Objective. The cochlear implant (CI) belongs to the most successful neuro-prostheses. Traditionally, the stimulating electrode arrays are inserted into the scala tympani (ST), the lower cochlear cavity, which enables simple surgical access. However, often deep insertion is blocked, e.g. by ossification, and the auditory nerve fibers (ANFs) of lower frequency regions cannot be stimulated causing severe restrictions in speech understanding. As an alternative, the CI can be inserted into the scala vestibuli (SV), the other upper cochlear cavity. Approach. In this computational study, the excitability of 25 ANFs are compared for stimulation with ST and SV implants. We employed a 3-dimensional realistic human cochlear model with lateral wall electrodes based on a μ-CT dataset and manually traced fibers. A finite element approach in combination with a compartment model of a spiral ganglion cell was used to simulate monophasic stimulation with anodic (ANO) and cathodic (CAT) pulses of 50 μs. Main results. ANO thresholds are lower in ST (mean/std = μ/σ = 189/55 μA) stimulation compared to SV (μ/σ = 323/119 μA) stimulation. Contrary, CAT thresholds are higher for the ST array (μ/σ = 165/42 μA) compared to the SV array (μ/σ = 122/46 μA). The threshold amplitude depends on the specific fiber-electrode spatial relationship, such as lateral distance from the cochlear axis, the angle between electrode and target ANF, and the curvature of the peripheral process. For CAT stimulation the SV electrodes show a higher selectivity leading to less cross-stimulation of additional fibers from different cochlear areas. Significance. We present a first simulation study with a human cochlear model that investigates an additional CI placement into the SV and its impact on the excitation behavior. Results predict comparable outcomes to ST electrodes which confirms that SV implantation might be an alternative for patients with a highly obstructed ST.
Toward calibration-free motor imagery brain–computer interfaces: a VGG-based convolutional neural network and WGAN approach
Authors: Habashi A G , Azab Ahmed M , Eldawlatly Seif , Aly Gamal M 
Published: July 2024

Abstract

Objective. Motor imagery (MI) represents one major paradigm of Brain–computer interfaces (BCIs) in which users rely on their electroencephalogram (EEG) signals to control the movement of objects. However, due to the inter-subject variability, MI BCIs require recording subject-dependent data to train machine learning classifiers that are used to identify the intended motor action. This represents a challenge in developing MI BCIs as it complicates its calibration and hinders the wide adoption of such a technology. Approach. This study focuses on enhancing cross-subject (CS) MI EEG classification using EEG spectrum images. The proposed calibration-free approach employs deep learning techniques for MI classification and Wasserstein Generative Adversarial Networks (WGAN) for data augmentation. The proposed WGAN generates synthetic spectrum images from the recorded MI-EEG to expand the training dataset; aiming to enhance the classifier’s performance. The proposed approach eliminates the need for any calibration data from the target subject, making it more suitable for real-world applications. Main results. To assess the robustness and efficacy of the proposed framework, we utilized the BCI competition IV-2B, IV-2 A, and IV-1 benchmark datasets, employing leave one-subject out validation. Our results demonstrate that using the proposed modified VGG-CNN classifier in addition to WGAN-generated data for augmentation leads to an enhancement in CS accuracy outperforming state-of-the-art methods. Significance. This approach could represent one step forward towards developing calibration-free BCI systems and hence broaden their applications.