Utilizing deep learning for automated detection of oral lesions: A multicenter study.

OBJECTIVES: We aim to develop a YOLOX-based convolutional neural network model for the precise detection of multiple oral lesions, including OLP, OLK, and OSCC, in patient photos. MATERIALS AND METHODS: We collected 1419 photos for model development and evaluation, conducting both a comparative analysis to gauge the model's capabilities and a multicenter evaluation to assess its diagnostic aid, where 24 participants from 14 centers across the nation were invited. We further integrated this model into a mobile application for rapid and accurate diagnostics. RESULTS: In the comparative analysis, our model overperformed the senior group (comprising three most experienced experts with more than 10 years of experience) in macro-average recall (85 % vs 77.5 %), precision (87.02 % vs 80.29 %), and specificity (95 % vs 92.5 %). In the multicenter model-assisted diagnosis evaluation, the dental, general, and community hospital groups showed significant improvement when aided by the model, reaching a level comparable to the senior group, with all macro-average metrics closely aligning or even surpassing with those of the latter (recall of 78.67 %, 74.72 %, 83.54 % vs 77.5 %, precision of 80.56 %, 76.42 %, 85.15 % vs 80.29 %, specificity of 92.89 %, 91.57 %, 94.51 % vs 92.5 %). CONCLUSION: Our model exhibited a high proficiency in detection of oral lesions, surpassing the performance of highly experienced specialists. The model can also help specialists and general dentists from dental and community hospitals in diagnosing oral lesions, reaching the level of highly experienced specialists. Moreover, our model's integration into a mobile application facilitated swift and precise diagnostic procedures.

Facile one-pot synthesis of a polyvinylpyrrolidone-based self-crosslinked fluorescent film.

A polyvinylpyrrolidone (PVP)-based fluorescent film with stable optical properties is successfully prepared in one pot without any additive. The reaction mechanism of ring-opening and self-crosslinking of linear PVP is proposed and demonstrated. The morphologies and the nanostructures of the fluorescent film as well as the unmodified film are investigated. The dye is incorporated into the film networks via covalent linkages, thus leading to the highly stable optical properties. The facile and effective synthesis approach opens a new way for the design of other multi-functional composite materials based on linear PVP.

A novel fluorescent probe for the detection of formaldehyde in real food samples, animal serum samples and gaseous formaldehyde.

Formaldehyde (FA) is widely used as an adhesion promoter and dyeing aid in industrial production. Ingestion of a certain amount of formaldehyde may cause corrosive burns in the mouth, throat, and digestive tract. Therefore, it is very necessary to use simple and effective detection methods to ensure human health and food safety. Herein, a novel fluorescent probe NFD based on naphthalimide for the detection of formaldehyde in food was designed and synthesized. The probe had a remarkable fluorescence response to formaldehyde at 554 nm. And it exhibited fascinating advantages of good selectivity, high sensitivity, and low detection limit. In addition, the solid sensor prepared by loading the probe on the filter paper was successfully realized the visual detection of liquid and gaseous formaldehyde. More importantly, the probe possessed excellent stability in the detection of formaldehyde in real food samples and animal serum samples.

Selective determination of trace thiamphenicol in milk and honey by molecularly imprinted polymer monolith microextraction and high-performance liquid chromatography.

A novel solid-phase microextraction (SPME) method based on molecularly imprinted polymer (MIP) monolith as the sorbent for the selective extraction of thiamphenicol (TAP) in milk and honey was developed. The newly developed MIP monolith was produced using TAP as the template molecule, 4-vinylpyridine (4-VP) as the functional monomer. The TAP-MIP monolith synthesized in a micropipette tip could be connected with syringes in different sizes simply to perform SPME process without any other treatment. The derivated MIP monolith showed high selectivity and enrichment ability for TAP. A simple, rapid and sensitive method for the determination of TAP in milk and honey using polymer monolith microextraction (PMME) based on the MIP monolith combined with high-performance liquid chromatography-photodiodes array detector was developed. Several parameters affecting MIP monolith microextraction were investigated, including the flow rate, volume, pH and salt concentration of sample, the type and volume of washing solution, the type and flow rate of eluent. The recovery of this method for TAP was investigated and high recoveries of 92.9-99.3% from milk and honey were obtained with relative standard deviations less than 4.9%.

Preparation And Antibacterial Effects Of Carboxymethyl Chitosan-Modified Photo-Responsive Camellia Sapogenin Derivative Cationic Liposomes.

BACKGROUND: Bacterial resistance to antibiotics is a persistent and intractable problem. The sapogenin isolated from the seeds of Camellia oleifera can inhibit antibiotic-resistant bacteria after structural modification. PURPOSE: This study aims to improve sapogenin's antibacterial activity and avoid bacterial resistance based on nano-preparation with photo responsiveness. METHODS: The liposome shell material of carboxymethyl chitosan-phosphatidyl ethanolamine (CMC-PE) was prepared using amidation reaction, and photo-responsive cationic (PCC) liposomes containing Camellia sapogenin derivative (CSD) and photosensitizer pheophorbide-a were prepared by film dispersion method. Encapsulation efficiency, drug loading, zeta potential, particle size distribution, morphology and stability of the PCC liposomes were determined by HPLC, particle size analyzer, transmission electron microscopy (TEM) and fluorescence microscopy. Photo-responsive release of CSD in the PCC liposomes was determined by laser (0.5 mW/cm2) at 665 nm. Antibacterial activity of the PCC liposomes with or without irradiation was analyzed by MIC50, MBC, MBIC50, and bacterial morphology to evaluate the antibacterial effects on amoxicillin resistant Escherichia coli and Staphylococcus aureus. RESULTS: Size distribution, zeta potential, encapsulation efficiency and drug loading of the PCC liposomes were 189.23 ± 2.12 nm, 18.80 ± 1.57 mV, 83.52 ± 1.53% and 2.83 ± 0.05%, respectively. The PCC liposomes had higher storage stability and gastrointestinal stability, and no obvious hemolytic toxicity to rabbit red blood cells and no cytotoxicity after incubation with Hela cells. The photosensitizer pheophorbide-a was uniformly dispersed in the phospholipid layer of the PCC liposomes and increased the CSD release after irradiation. The PCC liposomes could bind to bacteria and impaired their morphology and structure, and had significant bactericidal effect on amoxicillin resistant E. coli and S. aureus. CONCLUSION: The photo-responsive PCC liposomes are efficient antibacterial agents for avoidance of bacterial resistance against antibiotics.

cRGDfK-Grafted Small-Size Quercetin Micelles For Enhancing Therapy Efficacy Of Active Ingredient From The Chinese Medicinal Herb.

BACKGROUND: As an active ingredient of Chinese herbal medicine, quercetin (QU) can significantly induce apoptosis of tumor cells and give play to other effect such as decreasing both fibroblast population and collagen in cancer cell nest. However, the antitumor efficacy of quercetin was mostly evaluated at cellular level and rarely developed in vivo by intravenous injection, which may be ascribed to its inferior physicochemical properties including water insolubility, short plasma half-time, and insufficient enrichment in the tumor tissues. METHODS: The DSPE-PEG was used to construct quercetin-loaded micelles, and the integrin ligand cRGDfK was grafted to modify the nanocarrier for enhancing its cancer-specific homing. The MALDI-TOF-MS, DLS, TEM, and UV were orderly operated to characterize guidance molecules and micelles by morphology, size distribution, Zeta potential, and drug encapsulation efficiency. In addition, the surface plasmon resonance study and real-time confocal analysis were employed to demonstrate αvß3 integrin-overexpressing B16 cells-specific binding and uptake. After further pharmacodynamics studies in vitro and in vivo, we also evaluate systemic toxicity about cRGDfK-PM-QU. RESULTS: The cRGDfK was successfully stitched with DSPE-PEG and modified on the surface of micelles. The ligand modification enhanced the negative charges of the micelles, but it did not induce significant changes in particle size. The quercetin micelles were about 15 nm in size and negatively charged, and had spherical morphology and high drug encapsulation efficiency. In vitro, the cRGDfK-modified micelles (cRGDfK-PM) showed αvß3 integrin-overexpressing B16 cells-specific binding and uptake, and cRGDfK-PM-QU (QU loaded in cRGDfK-PM) induced more significant cell apoptosis and cytotoxic effects against B16 tumor cells than counterpart micelles (PM-QU). In vivo, the cRDGfK modification enhanced enrichment in B16 tumor tissue, improved the therapeutic efficacy of the quercetin-loaded micelles against B16 tumor, and exhibited lower systemic and pulmonary toxicity compared with counterpart micelles in the mouse mode. CONCLUSION: Quercetin as a natural product has triggered increasing interest in the antitumor field. In this study, cRGDfK-modified DSPE-PEG micelles significantly optimized quercetin therapeutic efficacy and pulmonary toxicity as well as lowered systemic toxicity.

[Konjac glucomannan-collagen -chitosan blend films (I)].

Konjac glucomannan-collagen-chitosan blend films were prepared successfully by the solvent-casting method and were characterized by FT-IR,X-ray diffraction, SEM and optical transmittance. Moreover, tensile strength, breaking extension, water absorption, water vapor permeation coefficients, adsorbability and penetrating rates were measured. The results indicated that some strong interaction and good compatibility existed among Konjac glucomannan /collagen and chitosan in the blend films. Some properties of the KCCS films were improved markedly in comparison with binary blend films or Konjac glucomannan, collagen and chitosan film. The results of culturing vessel endothelial cells on CKCS-5 film showed that the blend films have good cell compatibility which indicates the potential for a scalfold material in tissue engineering.

On-column enrichment and surface-enhanced Raman scattering detection in nanoparticles functionalized porous capillary monolith.

A monolithic column functionalized with gold nanoparticles (GNPs) was designed to provide ultrasensitive detection with surface-enhanced Raman scattering (SERS). The monolithic column based on poly (glycidyl methacrylate-co-ethylene dimethacrylate) (GMA-co-EDMA) was served as the enrichment sorbent to concentrate GNPs and targets. We found that 60 nm GNPs-functionalized monolithic columns demonstrated the best SERS enhancement, and the lowest detectable concentration for PATP and CV could be achieved at 10(-7) and 10(-11) M, respectively. Moreover, the columns exhibit a good reproducibility in both spot-to-spot (∼10%) and batch-to-batch (∼15%). The SERS monolithic column with a high sensitivity and reproducibility has a great potential in the field-based rapid detection of targets in complex real-world samples.

Electrospun Nanofibrous P(DLLA-CL) Balloons as Calcium Phosphate Cement Filled Containers for Bone Repair: in Vitro and in Vivo Studies.

The spinal surgeon community has expressed significant interest in applying calcium phosphate cement (CPC) for the treatment of vertebral compression fractures (VCFs) and minimizing its disadvantages, such as its water-induced collapsibility and poor mechanical properties, limiting its clinical use. In this work, novel biodegradable electrospun nanofibrous poly(d,l-lactic acid-ϵ-caprolactone) balloons (ENPBs) were prepared, and the separation, pressure, degradation, and new bone formation behaviors of the ENPBs when used as CPC-filled containers in vitro and in vivo were systematically analyzed and compared. CPC could be separated from surrounding bone tissues by ENPBs in vitro and in vivo. ENPB-CPCs (ENPBs serving as CPC-filled containers) exerted pressure on the surrounding bone microenvironment, which was enough to crush trabecular bone. Compared with the CPC implantation, ENPB-CPCs delayed the degradation of CPC (i.e., its water-induced collapsilibity). Finally, possible mechanisms behind the in vivo effects caused by ENPB-CPCs implanted into rabbit thighbones and pig vertebrae were proposed. This work suggests that ENPBs can be potentially applied as CPC-filled containers in vivo and provides an experimental basis for the clinical application of ENPBs for the treatment of VCFs. In addition, this work will be of benefit to the development of polymer-based medical implants in the future.

[Development of a new noninvasive blood sugar detector].

The level of blood sugar is an improtant indicator used in the diagnosis and management of diabetes mellitus. In this respect, polarimeter and blood sugar detector were conventionally and generally used in hospitals; However, the former one is already obsolete; the latter one is invasive. In this paper, the development of a novel noninvasive blood-sugar detector is described. The experiment indicate that this detector is nonivasive, safe, fast, and easy to operate, and it can be of wide application.

[The effects of ADAM28 AS-ODN on biological function of human gingival fibroblasts].

PURPOSE: To study the effects of a disintegrin and metalloproteinase 28 (ADAM28) antisense oligodeoxynucleotide (AS-ODN) on proliferation, differentiation and apoptosis of human gingival fibroblasts (HGFs), and analyze the possible mechanism. METHODS: Cell culture, gene transfection, MTT chromatometry, enzyme dynamics, and flow cytometry (FCM) techniques were used to detect the effects of ADAM28 AS-ODN on biological characteristics of HGFs after transfected into HGFs. The statistical differences were evaluated by SNK test with SPSS 16.0 software package. RESULTS: In ADAM28 AS-ODN group, the proliferation activity of HGFs decreased significantly. Cell percentage in S phase in AS-ODN group was notably lower than that of S-ODN and untransfected groups, and cell percentage in G2+M phase was remarkably lower than that of untransfected group. Cell proliferation index (PI=S+G2M) in AS-ODN group was significantly lower than that of the other two groups. There was a significant difference between the groups. In AS-ODN group, alkaline phosphatase (ALP) secretion activity and percentage of apoptotic cell notably increased. CONCLUSIONS: ADAM28 AS-ODN could inhibit HGFs proliferation significantly and influence the changes of cell cycle, promote HGFs differentiation and induce HGFs apoptosis remarkably.

Experimental imaging properties of immersion microscale spherical lenses.

Using the immersion lensing technique, the resolution of a conventional spherical lens can be improved by a factor of 1/n over its value in air (n, the refractive index of the immersion medium). Depending on the relative position between an object and a lens, either a real or a virtual image is formed. Here we report a new physical phenomenon experimentally observed in the microscale lens imaging. We find that when a microscale spherical lens is semi-immersed in a medium, the resolution of the lens is improved as it can intercept more fine details of the object. However, the microscale lens has two image channels for the fine and coarse details and two images corresponding to the two components can be formed simultaneously. Our findings will advance the understanding of the super-resolution imaging mechanisms in microscale lenses.

Preparation, characterization and application of organic-inorganic hybrid caffeine imprinted monolith.

The present work aims to synthesize an organic-inorganic hybrid caffeine imprinted monolith using one-step method. The synthesis conditions such as the type of inorganic precursor and porogenic solvent, the molar ratios of the monomer and cross-linker, the volume ratio of the inorganic alcoholysate and organic part were optimized. The morphology of the monolith was studied by scanning electron microscopy and Fourier transform infrared spectra. The imprinted factor of the monolith for caffeine reached 3.02. A simple, rapid and sensitive method for the determination of caffeine in children's milk using the organic-inorganic hybrid caffeine imprinted polymer monolith microextraction combined with high-performance liquid chromatography-photodiodes array detector was developed. Several parameters affecting the sample pretreatment were investigated, including the type, flow rate and volume of eluent, the flow rate and volume of sample solution. The assay exhibited a linear dynamic range of 8-500µgL(-1) with the correlation coefficient above 0.9987. Lower limits of detection (LOD, at S/N=3) and quantification (LOQ, at S/N=10) in children's milk samples were 2.7 and 8µgL(-1). Recoveries of caffeine from spiked children's milk ranged from 85 to 104% with relative standard deviations of less than 8.9%.

[Preparation and cytocompatibility of apatite-porous fibers composite].

OBJECTIVE: The purpose of this article was to prepare apatite-porous fibers composite through biominetic synthesis and to investigate its cytocompatibility. METHODS: Phosphate groups were incorporated into the surface of natural porous fiber-corncob by chemical modification. After precalcification, corncob was immersed into simulated body fluid. The surface of composite was observed through scanning electron microscope (SEM) and X-ray diffraction. Infant rat calvarias osteoblasts were isolated and expanded in vitro and the cells were seeded onto composite. Osteoblasts growth, proliferation and differentiation were assessed through SEM, MTT and alkaline phosphatase (ALP). RESULTS: Apatite crystal was formed on the surface of corncob after reaction. Cell adhered and spread well on the surface of the composite, having high abilities of proliferation and synthesis of ALP. CONCLUSION: There is good compatibility between the osteoblast and apatite-porous fibers composite. This composite may serve as a potential biomaterial used in bone repair and regeneration.

Amino-catalyzed fragmentation characteristics of polyamides containing N-methylpyrrole and N-methylimidazole by electrospray negative ionization mass spectrometry.

Different negative fragmentations of synthesized polyamides containing N-methylpyrrole and N-methylimidazole were analyzed by electrospray ionization tandem mass spectrometry with low-energy collision-induced dissociation. An interesting rearrangement derived from amino catalysis of N-methylimidazole was observed. The observation is useful for the study of the correlations between the sequences of polyamides and their mass fragmentation pathways.

[Study status of collagen-based biomaterials in drug release and tissue engineering].

OBJECTIVE: To introduce the development of the collagen materials in drug release and tissue engineering. METHODS: Literature review and complex analysis were adopted. RESULTS: In recent years, some good progress has been made in the studies of collagen, and study on collagen-based materials has become an investigative hotspot especially in tissue engineering. Some new collagen-based drug delivery and engineered materials have come into clinically-demonstrated moment, which will promote their clinical applications in tissue repairs. CONCLUSION: Collagen has been considered a good potential material in drug release, especially in the tissue-engineering field. To give collagen new characters we should pay more attention to grafting with different function branches through chemistry technique in the future work, except moderate cross-linking treatment or commingling with other nature or synthesized macromolecules.