Large Language Models can be Guided to Evade AI-Generated Text Detection

Large Language Models (LLMs) have demonstrated exceptional performance in a variety of tasks, including essay writing and question answering. However, it is crucial to address the potential misuse of these models, which can lead to detrimental outcomes such as plagiarism and spamming. Recently, several detectors have been proposed, including fine-tuned classifiers and various statistical methods. In this study, we reveal that with the aid of carefully crafted prompts, LLMs can effectively evade these detection systems. We propose a novel Substitution-based In-Context example Optimization method (SICO) to automatically generate such prompts. On three real-world tasks where LLMs can be misused, SICO successfully enables ChatGPT to evade six existing detectors, causing a significant 0.54 AUC drop on average. Surprisingly, in most cases these detectors perform even worse than random classifiers. These results firmly reveal the vulnerability of existing detectors. Finally, the strong performance of SICO suggests itself as a reliable evaluation protocol for any new detector in this field

Tocopherol attenuates the oxidative stress of BMSCs by inhibiting ferroptosis through the PI3k/AKT/mTOR pathway

Oxidative stress can induce bone tissue damage and the occurrence of multiple diseases. As a type of traditional medicine, tocopherol has been reported to have a strong antioxidant effect and contributes to osteogenic differentiation. The purpose of this study was to investigate the protective effect of tocopherol on the oxidative stress of rat bone marrow-derived mesenchymal stem cells (BMSCs) and the underlying mechanisms. By establishing an oxidative stress model in vitro, the cell counting kit-8 (CCK-8), reactive oxygen species (ROS) analysis, Western blot (WB), real-time PCR (RT-PCR), alkaline phosphatase (ALP) staining, and Alizarin Red staining (ARS) evaluated the effects of tocopherol on the cell viability, intracellular ROS levels, and osteogenic differentiation in BMSCs. In addition, ferroptosis-related markers were examined via Western blot, RT-PCR, and Mito-FerroGreen. Eventually, the PI3K/AKT/mTOR signaling pathway was explored. We found that tocopherol significantly maintained the cell viability, reduced intracellular ROS levels, upregulated the levels of anti-oxidative genes, promoted the levels of osteogenic-related proteins, and the mRNA of BMSCs stimulated by H2O2. More importantly, tocopherol inhibited ferroptosis and upregulated the phosphorylation levels of PI3K, AKT, and mTOR of BMSCs upon H2O2 stimulation. In summary, tocopherol protected BMSCs from oxidative stress damage via the inhibition of ferroptosis through the PI3K/AKT/mTOR pathway

Cellular Internalization-Induced Aggregation of Porous Silicon Nanoparticles for Ultrasound Imaging and Protein-Mediated Protection of Stem Cells

Nanotechnology employs multifunctional engineered materials in the nanoscale range that provides many opportunities for translational stem cell research and therapy. Here, a cell-penetrating peptide (virus-1 transactivator of transcription)-conjugated, porous silicon nanoparticle (TPSi NP) loaded with the Wnt3a protein to increase both the cell survival rate and the delivery precision of stem cell transplantation via a combinational theranostic strategy is presented. The TPSi NP with a pore size of 10.7 nm and inorganic framework enables high-efficiency loading of Wnt3a, prolongs Wnt3a release, and increases antioxidative stress activity in the labeled mesenchymal stem cells (MSCs), which are highly beneficial properties for cell protection in stem cell therapy for myocardial infarction. It is confirmed that the intracellular aggregation of TPSi NPs can highly amplify the acoustic scattering of the labeled MSCs, resulting in a 2.3-fold increase in the ultrasound (US) signal compared with that of unlabeled MSCs. The translational potential of the designed nanoagent for real-time US imaging-guided stem cell transplantation is confirmed via intramyocardial injection of labeled MSCs in a nude mouse model. It is proposed that the intracellular aggregation of protein drug-loaded TPSi NPs could be a simple but robust strategy for improving the therapeutic effect of stem cell therapy.Peer reviewe

Group-DIA: analyzing multiple data-independent acquisition mass spectrometry data files

Discovery proteomics has limited quantification capabilities because of stochastic precursor-ion selection. Several data-independent acquisition (DIA) methods have been proposed to overcome this limitation1, 2, 3, 4, including the sequential-window acquisition of all theoretical mass spectra (SWATH-MS)4.the National Science Foundation (NSF) of China (grants 91429301 and 31221065), 973 Program 2015CB553800, National Major Project 2013ZX10002-002, 111 Project B12001, funding from Xiamen City (grant 3502Z20130027) and the NSF of China for Fostering Talents in Basic Research (grant J1310027)

Pediatric obstructive sleep apnea diagnosis: leveraging machine learning with linear discriminant analysis

ObjectiveThe objective of this study was to investigate the effectiveness of a machine learning algorithm in diagnosing OSA in children based on clinical features that can be obtained in nonnocturnal and nonmedical environments.Patients and methodsThis study was conducted at Beijing Children's Hospital from April 2018 to October 2019. The participants in this study were 2464 children aged 3–18 suspected of having OSA who underwent clinical data collection and polysomnography(PSG). Participants’ data were randomly divided into a training set and a testing set at a ratio of 8:2. The elastic net algorithm was used for feature selection to simplify the model. Stratified 10-fold cross-validation was repeated five times to ensure the robustness of the results.ResultsFeature selection using Elastic Net resulted in 47 features for AHI ≥5 and 31 features for AHI ≥10 being retained. The machine learning model using these selected features achieved an average AUC of 0.73 for AHI ≥5 and 0.78 for AHI ≥10 when tested externally, outperforming models based on PSG questionnaire features. Linear Discriminant Analysis using the selected features identified OSA with a sensitivity of 44% and specificity of 90%, providing a feasible clinical alternative to PSG for stratifying OSA severity.ConclusionsThis study shows that a machine learning model based on children's clinical features effectively identifies OSA in children. Establishing a machine learning screening model based on the clinical features of the target population may be a feasible clinical alternative to nocturnal OSA sleep diagnosis

Periosteum Containing Implicit Stem Cells: A Progressive Source of Inspiration for Bone Tissue Regeneration

The periosteum is known as the thin connective tissue covering most bone surfaces. Its extrusive bone regeneration capacity was confirmed from the very first century-old studies. Recently, pluripotent stem cells in the periosteum with unique physiological properties were unveiled. Existing in dynamic contexts and regulated by complex molecular networks, periosteal stem cells emerge as having strong capabilities of proliferation and multipotential differentiation. Through continuous exploration of studies, we are now starting to acquire more insight into the great potential of the periosteum in bone formation and repair in situ or ectopically. It is undeniable that the periosteum is developing further into a more promising strategy to be harnessed in bone tissue regeneration. Here, we summarized the development and structure of the periosteum, cell markers, and the biological features of periosteal stem cells. Then, we reviewed their pivotal role in bone repair and the underlying molecular regulation. The understanding of periosteum-related cellular and molecular content will help enhance future research efforts and application transformation of the periosteum

Influence of Dental Implant Surface Modifications on Osseointegration and Biofilm Attachment

Dental implants have been widely applied in partially and fully edentulous patients and have shown predictable clinical outcomes, but there are still many cases of implant failures, such as osseointegration failure and peri-implant inflammation. To improve the success rate of implants, especially in improving osseointegration and antibacterial performance, various methods of implant surface modification have been applied. Surface modification methods covered include sandblasting with large-grit corundum and acid etched (SLA), plasma spraying, plasma immersion ion implantation (PIII), sputter-deposition, selective laser melting (SLM), anodic oxidation, microarc oxidation, sol-gel coating, alkaline heat treatment (AH) and Layer-by-Layer (LBL) self-assembly. This review comprehensively summarizes the influence of each method on osseointegration and biofilm attachment. The mechanical, chemical and biological disadvantages of these methods are involved. Besides, the mechanisms behind such techniques as increasing surface roughness to expand superficial area and enhance the adhesion of osteoblastic cells are discussed

Prognostic significance of PTK7 in human malignancies

Background. Protein tyrosine kinase 7 (PTK7) is a member of receptor protein tyrosine kinase-like molecules, which is involved in tumorigenesis. However, the association between PTK7 expression and its pathological significance in survival prognosis remains under investigation. The purpose of this meta-analysis is to clarify the prognostic value of PTK7 expression in human malignancies. Methods. A comprehensive literature search was performed in databases of PubMed, Embase and Cochrane Library. The statistical procedures were conducted by Stata 14.0 and the effect size was displayed by model of relative risk. Subgroup analyses were additionally implemented to disclose the potential confounding elements. Sensitivity analysis was used for evaluating the outcome stability, both Begg’s test and Egger’s test were utilized to detect the publication bias across the included studies. Results. We identified 11 studies published with a total sample-size of 2431 participants. Patients with higher PTK7 expression were significantly associated with cancer risk (RR=2.995, 95% CI: 1.048-8.56, p=0.041, random model), and histological grade (RR=0.696, 95% CI: 0.499-0.972, p=0.033, random model). PTK7 was also found to be an unfavorable prognostic marker for overall survival (HR=2.621 95% CI: 1.980-3.468, p=0.000, fixed model) and shorter disease free survival (HR=2.242, 95% CI: 1.112-4.521, p=0.024, random model). Conclusions. Higher expression of PTK7 significantly indicates worse prognosis in human malignancies

Surface Modification of Titanium by Micro-Arc Oxidation in Promoting Schwann Cell Proliferation and Secretion of Neurotrophic Factors

Titanium and its alloys have been widely used in the field of oral implants over the past few decades. However, the effect of micro-arc oxidation modified titanium surface on Schwann cells has not been studied, which is of great significance for nerve regeneration around implants and improvement of osseoperception. In this study, the characterization of the titanium surface modified by micro-arc oxidation (MAO) was detected by scanning electron microscope (SEM), XPS and a contact angle measurement system. Schwann cells (SCs) were cultured on titanium surfaces of micro-arc oxidation (MAO) and pure titanium (Ti). At different time points, the morphology and adhesion of SCs on the titanium surfaces were observed by SEM. Cell proliferation activity was detected by the CCK-8 method. The expression levels of mRNA and proteins of nerve growth factor (NGF) and glial-derived neurotrophic factor (GDNF) were detected by RT-PCR, immunofluorescence and western blot. The results of this in vitro study revealed that micro-arc-oxidation-modified titanium surfaces promoted Schwann cell proliferation and secretion of neurotrophic factors compared with pure titanium. CCK-8 results showed that the number of Schwann cells on MAO surfaces was significantly higher than that of the Ti group on day 7. The mRNA expressions of Ngf and Gdnf were up-regulated in both groups from day 1 to day 7. On day 3 and day 7, the gene expression of Ngf in the MAO group was significantly higher than that of the Ti group. On day 7, the MAO group appeared significantly up-regulated in gene expression level of Gdnf. The results of western blot were consistent. Micro-arc oxidation modification provides an accurate and effective method for promoting nerve regeneration of titanium microtopography coatings, which have potential significance for promoting patients’ osseoperception ability in clinical practice