Convolutional neural network-based measurement of crown-implant ratio for implant-supported prostheses.

STATEMENT OF PROBLEM: Research has revealed that the crown-implant ratio (CIR) is a critical variable influencing the long-term stability of implant-supported prostheses in the oral cavity. Nevertheless, inefficient manual measurement and varied measurement methods have caused significant inconvenience in both clinical and scientific work. PURPOSE: This study aimed to develop an automated system for detecting the CIR of implant-supported prostheses from radiographs, with the objective of enhancing the efficiency of radiograph interpretation for dentists. MATERIAL AND METHODS: The method for measuring the CIR of implant-supported prostheses was based on convolutional neural networks (CNNs) and was designed to recognize implant-supported prostheses and identify key points around it. The experiment used the You Only Look Once version 4 (Yolov4) to locate the implant-supported prosthesis using a rectangular frame. Subsequently, two CNNs were used to identify key points. The first CNN determined the general position of the feature points, while the second CNN finetuned the output of the first network to precisely locate the key points. The network underwent testing on a self-built dataset, and the anatomic CIR and clinical CIR were obtained simultaneously through the vertical distance method. Key point accuracy was validated through Normalized Error (NE) values, and a set of data was selected to compare machine and manual measurement results. For statistical analysis, the paired t test was applied (α=.05). RESULTS: A dataset comprising 1106 images was constructed. The integration of multiple networks demonstrated satisfactory recognition of implant-supported prostheses and their surrounding key points. The average NE value for key points indicated a high level of accuracy. Statistical studies confirmed no significant difference in the crown-implant ratio between machine and manual measurement results (P>.05). CONCLUSIONS: Machine learning proved effective in identifying implant-supported prostheses and detecting their crown-implant ratios. If applied as a clinical tool for analyzing radiographs, this research can assist dentists in efficiently and accurately obtaining crown-implant ratio results.

Efficacy of Coxsackievirus A5 Vaccine Candidates in an Actively Immunized Mouse Model.

Coxsackievirus A5 (CV-A5) has recently emerged as a main hand, foot, and mouth disease (HFMD) pathogen. Following a large-scale vaccination campaign against enterovirus 71 (EV-71) in China, the number of HFMD-associated cases with EV-71 was reduced, especially severe and fatal cases. However, the total number of HFMD cases remains high, as HFMD is also caused by other enterovirus serotypes. A multivalent HFMD vaccine containing 4 or 6 antigens of enterovirus serotypes is urgently needed. A formaldehyde-inactivated CV-A5 vaccine derived from Vero cells was used to inoculate newborn Kunming mice on days 3 and 10. The mice were challenged on day 14 with a mouse-adapted CV-A5 strain at a dose that was lethal for 14-day-old suckling mice. Within 14 days postchallenge, groups of mice immunized with three formulations, empty particles (EPs), full particles (FPs), and a mixture of the EP and FP vaccine candidates, all survived, while 100% of the mock-immunized mice died. Neutralizing antibodies (NtAbs) were detected in the sera of immunized mice, and the NtAb levels were correlated with the survival rate of the challenged mice. The virus loads in organs were reduced, and pathological changes and viral protein expression were weak or not observed in the immunized mice compared with those in alum-inoculated control mice. Another interesting finding was the identification of CV-A5 dense particles (DPs), facilitating morphogenesis study. These results demonstrated that the Vero cell-adapted CV-A5 strain is a promising vaccine candidate and could be used as a multivalent HFMD vaccine component in the future.IMPORTANCE The vaccine candidate strain CV-A5 was produced with a high infectivity titer and a high viral particle yield. Three particle forms, empty particles (EPs), full particles (FPs), and dense particles (DPs), were obtained and characterized after purification. The immunogenicities of EP, FP, and the EP and FP mixture were evaluated in mice. Mouse-adapted CV-A5 was generated as a challenge strain to infect 14-day-old mice. An active immunization challenge mouse model was established to evaluate the efficacy of the inactivated vaccine candidate. This animal model mimics vaccination, similar to immune responses of the vaccinated. The animal model also tests protective efficacy in response to the vaccine against the disease. This work is important for the preparation of multivalent vaccines against HFMD caused by different emerging strains.

Minimum residual root dentin thickness of mandibular premolars restored with a post: A finite element analysis study.

STATEMENT OF PROBLEM: Thin root dentin after post space preparation will increase the risk of root fracture. However, the minimum residual root dentin thickness to be preserved after post space preparation is unclear. PURPOSE: The purpose of this finite element analysis (FEA) study was to measure the residual root dentin thicknesses and analyze the stress distributions of post-restored mandibular premolars. MATERIAL AND METHODS: The cone beam computed tomography (CBCT) data of 90 first and second mandibular premolars from Chinese participants (44 men, 46 women; aged between 20 and 79 years) were analyzed. Cross-sections 5 to 9 mm from the radiologic apex were used to measure the buccolingual and mesiodistal root diameters. The probability that the residual thickness of the buccolingual and mesiodistal root walls would be no less than 0.5, 0.6, 0.7, 0.8, 0.9, and 1 mm after post space preparation with a #2 Peeso reamer was calculated. Six 3-dimensional finite element models of cast post-restored mandibular premolars with 0.5, 0.6, 0.7, 0.8, 0.9, and 1 mm mesial and distal root dentin thicknesses were established. A static force of 100 N was applied to the buccal cusp tip at 45, 60, 75, and 90 degrees to the long axis of the tooth, and the maximum tensile stress and von Mises stress were analyzed. The Bonferroni post hoc test (αcorrected=.003) was used for multiple comparisons. RESULTS: The buccolingual root diameter of mandibular premolars was wider than the mesiodistal root diameter. The probabilities that the mesiodistal residual root dentin thickness of mandibular first and second premolars at 5 mm from the apex would be no less than 1 mm after post space preparation with a #2 Peeso reamer were only 10% and 28%, respectively. The maximum tensile stress was at a minimum when the mesial and distal residual root dentin thickness was 0.6 mm in the external cervical dentin adjacent to the crestal bone and 1 mm in the apical dentin corresponding to the apex of the post. The maximum tensile stress of the mandibular premolar model with 0.6-mm mesial and distal residual root dentin thicknesses was lower than that with 0.9 mm and 1.0 mm thicknesses (Pcorrected<.001). CONCLUSIONS: Short posts or smaller instruments for post space preparation are recommended to obtain a 1-mm residual root dentin thickness in the mesiodistal direction of mandibular premolars. If a 1-mm thickness cannot be preserved, a minimum residual root dentin thickness of 0.6 to 0.9 mm in the mesiodistal direction should be retained.

[Latest Research Findings on the Mechanism of Periodontal Pathogens in Cardiovascular Disease].

Cardiovascular disease (CVD) is a major cause of death worldwide. Research findings indicate that periodontal infection is an independent risk factor for CVD. Periodontal pathogens can cause cardiovascular diseases through various pathways, including direct invasion, induction of platelet activation and agglutination, immune inflammatory response, bacteremia, and oxidative stress. Moreover, CVD symptoms are relieved after the patients undergo periodontal interventional treatment. There have been substantial findings indicating that there may be a close connection between periodontal disease and CVD. However, periodontal disease is a chronic disease. The treatment of periodontal diseases and the improvement of periodontal health require long-term efforts. Long-term effective reduction of the incidence of CVD in clinical practice through prevention of periodontal disease remains a challenging area of study. Here we summarized and reported the latest findings on the mechanism of action of periodontal pathogens in cardiovascular diseases, intending to contribute to the better understanding of the pathogenesis of CVD and to provide potential targets and new ideas for its prevention and treatment.

BiVO4/Fe3O4@polydopamine superparticles for tumor multimodal imaging and synergistic therapy.

BACKGROUND: Despite tremendous progress has been achieved in tumor theranostic over the past decade, accurate identification and complete eradication of tumor cells remain a great challenge owing to the limitation of single imaging modality and therapeutic strategy. RESULTS: Herein, we successfully design and construct BiVO4/Fe3O4@polydopamine (PDA) superparticles (SPs) for computed tomography (CT)/photoacoustic (PA)/magnetic resonance (MR) multimodal imaging and radiotherapy (RT)/photothermal therapy (PTT) synergistic therapy toward oral epithelial carcinoma. On the one hand, BiVO4 NPs endow BiVO4/Fe3O4@PDA SPs with impressive X-ray absorption capability due to the high X-ray attenuation coefficient of Bi, which is beneficial for their utilization as radiosensitizers for CT imaging and RT. On the other hand, Fe3O4 NPs impart BiVO4/Fe3O4@PDA SPs with the superparamagnetic property as a T2-weighted contrast agent for MR imaging. Importantly, the aggregation of Fe3O4 NPs in SPs and the presence of PDA shell greatly improve the photothermal conversion capability of SPs, making BiVO4/Fe3O4@PDA SPs as an ideal photothermal transducer for PA imaging and PTT. By integrating advantages of various imaging modalities (CT/PA/MR) and therapeutic strategies (RT/PTT), our BiVO4/Fe3O4@PDA SPs exhibit the sensitive multimodal imaging feature and superior synergistic therapeutic efficacy on tumors. CONCLUSIONS: Since there are many kinds of building blocks with unique properties appropriating for self-assembly, our work may largely enrich the library of nanomateirals for tumor diagnosis and treatment.

Fault Diagnosis of Rotating Machinery Based on Improved Self-Supervised Learning Method and Very Few Labeled Samples.

Convolution neural network (CNN)-based fault diagnosis methods have been widely adopted to obtain representative features and used to classify fault modes due to their prominent feature extraction capability. However, a large number of labeled samples are required to support the algorithm of CNNs, and, in the case of a limited amount of labeled samples, this may lead to overfitting. In this article, a novel ResNet-based method is developed to achieve fault diagnoses for machines with very few samples. To be specific, data transformation combinations (DTCs) are designed based on mutual information. It is worth noting that the selected DTC, which can complete the training process of the 1-D ResNet quickly without increasing the amount of training data, can be randomly used for any batch training data. Meanwhile, a self-supervised learning method called 1-D SimCLR is adopted to obtain an effective feature encoder, which can be optimized with very few unlabeled samples. Then, a fault diagnosis model named DTC-SimCLR is constructed by combining the selected data transformation combination, the obtained feature encoder and a fully-connected layer-based classifier. In DTC-SimCLR, the parameters of the feature encoder are fixed, and the classifier is trained with very few labeled samples. Two machine fault datasets from a cutting tooth and a bearing are conducted to evaluate the performance of DTC-SimCLR. Testing results show that DTC-SimCLR has superior performance and diagnostic accuracy with very few samples.

Simple Way of Facilitating Reduction the Fragment for Fractures With Condyle.

To describe a technique that uses a fixation screw with a steel wire ring which is implanted into the mandibular to facilitate the condylar fracture reduction. This technique has been used on 382 patients over the last 8 years from the Department of Oral and Cranio-Maxillofacial Science of Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China. No complication has been encountered. Applying this approach, the displaced proximal condylar fragment can be found quickly, and then the fragment can be effectively prevented from being broken again in the reduction process.

Polyethylene glycol 400 significantly enhances the stimulation of 2-phenoxyethanol on Vibrio qinghaiensis sp.-Q67 bioluminescence.

Previous studies demonstrated long-term stimulation of some commercial personal care products (PCPs) on freshwater luminescent bacteria Vibrio qinghaiensis sp.-Q67 (Q67). However, whether a certain component can affect mixture's hormetic effect is still unknown. In this paper, two of ingredients in PCPs, 2-phenoxyethanol (PhE) and polyethylene glycol 400 (PEG400), were selected as object compounds to explore the relationship between concentration-response (CR) of mixtures and that of a single component. It was found that PEG400 has monotonic CR (MCR) on Q67 both at the short-term (0.25 h) and long-term (12 h) exposures while PhE has MCR at 0.25 h and hormetic CR (HCR) at 12 h. Here, the concentration-response curves (CRCs) of PEG400 at 0.25 and 12 h are overlapped each other and the CRCs of PEG400 are on the right of PhE. If the pEC50 is taken as a toxic index, the toxicities of PEG400 at two times are basically the same, and those of PhE are the same, too, but PhE is twice as toxic as PEG400. For the mixtures of PEG400 and PhE, all rays except R1 have MCRs at 0.25 h while all rays have HCRs at 12 h where the higher the mixture ratio of PhE is, the more negative the maximum stimulation effect is. More importantly, the Emin values of all rays are more negative (1.79-3.17-fold) than that of PhE worked alone, which implies that the introduction of PEG400 significantly enhances stimulative effect of PhE. At 0.25 h, all binary mixture rays but R1 produce a low-concentration additive action and high-concentration synergism. At 12 h, all rays display additive action, antagonism, additive action, and synergism in turn when the concentration changes from low to high. The overall findings suggested toxicological interactions should be considered in the risk assessment of PCPs and their potential impacts on ecological balances.

Modulation of the Acetone/Butanol Ratio during Fermentation of Corn Stover-Derived Hydrolysate by Clostridium beijerinckii Strain NCIMB 8052.

Producing biobutanol from lignocellulosic biomass has shown promise to ultimately reduce greenhouse gases and alleviate the global energy crisis. However, because of the recalcitrance of a lignocellulosic biomass, a pretreatment of the substrate is needed which in many cases releases soluble lignin compounds (SLCs), which inhibit growth of butanol-producing clostridia. In this study, we found that SLCs changed the acetone/butanol ratio (A/B ratio) during butanol fermentation. The typical A/B molar ratio during Clostridium beijerinckii NCIMB 8052 batch fermentation with glucose as the carbon source is about 0.5. In the present study, the A/B molar ratio during batch fermentation with a lignocellulosic hydrolysate as the carbon source was 0.95 at the end of fermentation. Structural and redox potential changes of the SLCs were characterized before and after fermentation by using gas chromatography/mass spectrometry and electrochemical analyses, which indicated that some exogenous SLCs were involved in distributing electron flow to C. beijerinckii, leading to modulation of the redox balance. This was further demonstrated by the NADH/NAD+ ratio and trxB gene expression profile assays at the onset of solventogenic growth. As a result, the A/B ratio of end products changed significantly during C. beijerinckii fermentation using corn stover-derived hydrolysate as the carbon source compared to glucose as the carbon source. These results revealed that SLCs not only inhibited cell growth but also modulated the A/B ratio during C. beijerinckii butanol fermentation.IMPORTANCE Bioconversion of lignocellulosic feedstocks to butanol involves pretreatment, during which hundreds of soluble lignin compounds (SLCs) form. Most of these SLCs inhibit growth of solvent-producing clostridia. However, the mechanism by which these compounds modulate electron flow in clostridia remains elusive. In this study, the results revealed that SLCs changed redox balance by producing oxidative stress and modulating electron flow as electron donors. Production of H2 and acetone was stimulated, while butanol production remained unchanged, which led to a high A/B ratio during C. beijerinckii fermentation using corn stover-derived hydrolysate as the carbon source. These observations provide insight into utilizing C. beijerinckii to produce butanol from a lignocellulosic biomass.

Comparative efficacy of Glubran and polyvinyl-alcohol particles in the embolization of meningiomas.

PURPOSE: Preoperative embolization of meningiomas decreases intraoperative bleeding and shortens operation time. However, in meningiomas predominantly vascularized by the internal carotid artery (ICA) or vertebral artery (VA) branches, embolization of external carotid artery feeder branches may lead to a hemodynamic increase in blood supply from the ICA or VA, whereas embolization of ICA or VA feeder branches with particle embolic agents may be associated with complications. This study investigated the safety and efficacy of Glubran, a liquid embolic agent, for the embolization of this type of meningioma compared with polyvinyl-alcohol (PVA) particles. MATERIALS AND METHODS: From January 2006 to June 2015, 157 consecutive patients (98 females; mean age = 48.3 years) who suffered from meningiomas and were preoperatively referred for embolization were retrospectively analyzed. Glubran (n = 40) and PVA (n = 55) were used to devascularize tumors. Sixty-two patients were not embolized because of dangerous anastomosis or other tumor characteristics. Intraoperative blood loss, intraoperative time, degree of angiographic devascularization and embolization-related complications were analyzed. RESULTS: The intraoperative blood loss and operative time were significantly lower in the Glubran-embolized versus non-embolized group. Furthermore, Glubran embolization significantly reduced intraoperative blood loss and operative time for meningiomas that received their primary blood supply from the ICA and/or VA compared with PVA embolization. CONCLUSIONS: Preoperative meningioma embolization with Glubran decreases intraoperative blood loss and operative time. Furthermore, embolization with Glubran produces more effective devascularization compared with PVA for meningiomas supplied by the ICA and/or VA. Thus, Glubran may represent a better embolic agent for this meningioma subtype.

Development of miniaturized sorbent membrane funnel-based spray platform for biological analysis.

In this work, a miniaturized solid-phase extraction (SPE) platform, called sorbent membrane funnel, which permits in situ cleanup prior to membrane funnel-based spray analysis was developed. The fabrication of funnel and the mounting of SPE sorbent were simple and straightforward by a homemade punching system. Using different sorbents, the SPE sorbent funnel has been successfully applied in spray analysis of drug molecules spiked in human plasma, trypsin digested solution of bovine serum albumin in the presence of high concentration of chaotropic reagents, and phosphopeptides in the tryptic digested solution of casein. The results demonstrated that SPE sorbent attached membrane funnels can be a useful tool in common metabolomic and proteomic applications.

Inhibition of Nav1.7 channels by methyl eugenol as a mechanism underlying its antinociceptive and anesthetic actions.

AIM: Methyl eugenol is a major active component extracted from the Chinese herb Asari Radix et Rhizoma, which has been used to treat toothache and other pain. Previous in vivo studies have shown that methyl eugenol has anesthetic and antinociceptive effects. The aim of this study was to determine the possible mechanism underlying its effect on nervous system disorders. METHODS: The direct interaction of methyl eugenol with Na(+) channels was explored and characterized using electrophysiological recordings from Nav1.7-transfected CHO cells. RESULTS: In whole-cell patch clamp mode, methyl eugenol tonically inhibited peripheral nerve Nav1.7 currents in a concentration- and voltage-dependent manner, with an IC50 of 295 µmol/L at a -100 mV holding potential. Functionally, methyl eugenol preferentially bound to Nav1.7 channels in the inactivated and/or open state, with weaker binding to channels in the resting state. Thus, in the presence of methyl eugenol, Nav1.7 channels exhibited reduced availability for activation in a steady-state inactivation protocol, strong use-dependent inhibition, enhanced binding kinetics, and slow recovery from inactivation compared to untreated channels. An estimation of the affinity of methyl eugenol for the resting and inactivated states of the channel also demonstrated that methyl eugenol preferentially binds to inactivated channels, with a 6.4 times greater affinity compared to channels in the resting state. The failure of inactivated channels to completely recover to control levels at higher concentrations of methyl eugenol implies that the drug may drive more drug-bound, fast-inactivated channels into drug-bound, slow-inactivated channels. CONCLUSION: Methyl eugenol is a potential candidate as an effective local anesthetic and analgesic. The antinociceptive and anesthetic effects of methyl eugenol result from the inhibitory action of methyl eugenol on peripheral Na(+) channels.

Advancing Spinal Cord Injury Bioimaging and Repair with Multifunctional Gold Nanodots Tracking.

High levels of reactive oxygen species (ROS) are known to play a critical role in the secondary cascade of spinal cord injury (SCI). The scavenging of ROS has emerged as a promising approach for alleviating acute SCI. Moreover, identifying the precise location of the SCI site remains challenging. Enhancing the visualization of the spinal cord and improving the ability to distinguish the lesion site are crucial for accurate and safe treatment. Therefore, there is an urgent clinical need to develop a biomaterial that integrates diagnosis and treatment for SCI. Herein, ultra-small-sized gold nanodots (AuNDs) were designed for dual-mode imaging-guided precision treatment of SCI. The designed AuNDs demonstrate two important functions. First, they effectively scavenge ROS, inhibit oxidative stress, reduce the infiltration of inflammatory cells, and prevent apoptosis. This leads to a significant improvement in SCI repair and promotes a functional recovery after injury. Second, leveraging their excellent dual-mode imaging capabilities, the AuNDs enable rapid and accurate identification of SCI sites. The high contrast observed between the injured and adjacent uninjured areas highlights the tremendous potential of AuNDs for SCI detection. Overall, by integrating ROS scavenging and dual-mode imaging in a single biomaterial, our work on functionalized AuNDs provides a promising strategy for the clinical diagnosis and treatment of SCI.

Humoral and cellular immunogenicity and efficacy of a coxsackievirus A10 vaccine in mice.

Coxsackievirus A10 (CV-A10) has become one of the major pathogens of hand, foot and mouth disease (HFMD), and studies on the vaccine and animal model of CV-A10 are still far from complete. Our study used a mouse-adapted CV-A10 strain, which was lethal for 14-day-old mice, to develop an infected mouse model. Then this model was employed to establish an actively immunized-challenged mouse model to evaluate the efficacy of a formaldehyde-inactivated CV-A10 vaccine, which was prepared from a Vero cell-adapted strain. CV-A10 vaccine at a dose of 0.5 or 2.0 µg was inoculated intraperitoneally in neonatal Kunming mice on the third and ninth day. Then the mice were challenged on day 14. The survival rate of mice immunized with 0.5 or 2.0 µg vaccine were 90% and 100%, respectively, while all Alum-inoculated mice died. Compared to those in the two vaccinated groups, the Alum-inoculated mice showed severe pathological damage, strong viral protein expression and high viral loads. The antisera from vaccinated mice showed high level of neutralizing antibodies against CV-A10. Meanwhile, three potential T cell epitopes located at the carboxyl-terminal regions of the VP1 and VP3 were identified and exhibited CV-A10 serotype-specific. The humoral and cellular immunogenicity analysis showed that immunization with two doses of the vaccine elicited CV-A10 specific neutralizing antibody and T cell response in BALB/c mice. Collectively, these findings indicated that this actively immunized-challenged mouse model will be invaluable in future studies on CV-A10 pathogenesis and evaluation of vaccine candidates.

N, N-bis (2-hydroxyethyl) malonamide based amidoxime functionalized polymer immobilized in biomembranes for highly selective adsorption of uranium(VI).

Amidoxime compounds have been widely used in metal separation and recovery because of their excellent chelating properties to metal ions, especially to uranium (VI). In this study, N, N-bis (2-hydroxyethyl) malonamide was obtained from ethanolamine and dimethyl malonate, and used to prepare a two-dimensional network polymer, then the obtained polymer was immobilized in an environmentally friendly chitosan biomembrane, which enhanced its stability and hydrophobicity, meanwhile the amidoxime functionalization was achieved by oximation reaction of bromoacetonitrile, the application of the material further extends to uranium (VI) separation in solutions. Due to the synergistic action of amide group and amidoxime group, poly (ethanolamine-malonamide) based amidoxime biomembranes (PEA-AOM) showed extraordinary adsorption effect on uranium (VI), among which the saturation adsorption capacity of PEA-AOM-2 was 748.64 mg/g. PEA-AOM-2 also had good reusability (following five cycles of adsorption-desorption, the recovery rate maintained at 88%) and selectivity for uranium (VI), showing satisfactory results in competitive ion coexistence system and simulated seawater experiments. This study demonstrated that PEA-AOM-2 provided a new option for uranium (VI) separation in complex environment and low-concentration uranium background.

Patient-related factors related to prolonged preparation-to-colonoscopy interval and insufficient purgative intake before colonoscopy: A post-hoc observational study.

OBJECTIVES: Prolonged preparation-to-colonoscopy (PC) interval and insufficient purgative intake (PI) are two important indicators for quality of bowel preparation for colonoscopy. We aimed to investigate patient-related factors associated with increased PC interval or insufficient PI. METHODS: The post-hoc regression analyses were performed using the data from two prospective studies (NCT04434625 and NCT04101097). Patients receiving reinforced instructions for bowel preparation were recruited. The co-primary outcomes included prolonged PC interval or insufficient PI. RESULTS: Altogether 1806 patients from five endoscopic centers underwent bowel preparation from September 2019 to March 2021. The cut-off values were 6 h for PC interval and 80% for PI. In all, 116 (6.4%) and 73 (4.0%) presented an extended PC interval and insufficient PI, respectively. Multivariate logistic regression analysis showed that a low education level was significantly associated with PC interval ≥6 h. Female sex, body mass index (BMI), and coronary artery disease (CAD) were found to be significantly correlated with insufficient PI in univariate analysis, while multivariate analysis demonstrated BMI <20 kg/m2 (odds ratio [OR] 4.14, 95% confidence interval [CI] 1.92-8.94, P < 0.001) and 20-25 kg/m2 (OR 2.23, 95% CI 1.33-3.73, P = 0.002) and CAD (OR 3.23, 95% CI 1.22-8.53, P = 0.018) were identified as independent risk factors for PI <80%. CONCLUSIONS: In spite of reinforced education, a number of patients did not follow the instructions for bowel preparation. The factors for a prolonged PC interval did not overlap with those for insufficient PI. Individualized interference may be considered in different subpopulations.

Reporter Coxsackievirus A5 Expressing iLOV Fluorescent Protein or Luciferase Used for Rapid Neutralizing Assay in Cells and Living Imaging in Mice.

Coxsackievirus A5 (CV-A5) is a re-emerging enterovirus that causes hand, foot, and mouth disease in children under five years of age. CV-A5-M14-611 is a mouse-adapted strain that can infect orally and lead to the death of 14-day-old mice. Here, recombinants based on CV-A5-M14-611 were constructed carrying three reporter genes in different lengths. Smaller fluorescent marker proteins, light, oxygen, voltage sensing (iLOV), and nano luciferase (Nluc) were proven to be able to express efficiently in vitro. However, the recombinant with the largest insertion of the red fluorescence protein gene (DsRed) was not rescued. The construction strategy of reporter viruses was to insert the foreign genes between the C-terminus of VP1 and the N-terminus of 2A genes and to add a 2A protease cleavage domain at both ends of the insertions. The iLOV-tagged or Nluc-tagged recombinants, CV-A5-iLOV or CV-A5-Nluc, exhibited a high capacity for viral replication, genetic stability in cells and pathogenicity in mice. They were used to establish a rapid, inexpensive and convenient neutralizing antibody assay and greatly facilitated virus neutralizing antibody titration. Living imaging was performed on mice with CV-A5-Nluc, which exhibited specific bioluminescence in virus-disseminated organs, while fluorescence induced by CV-A5-iLOV was weakly detected. The reporter-gene-tagged CV-A5 can be used to study the infection and mechanisms of CV-A5 pathogenicity in a mouse model. They can also be used to establish rapid and sensitive assays for detecting neutralizing antibodies.

Identification of specific and shared epitopes at the extreme N-terminal VP1 of Coxsackievirus A4, A2 and A5 by monoclonal antibodies.

Hand, foot and mouth disease (HFMD) is caused by a variety of serotypes in species A of the Enterovirus genus, including recently re-emerged Coxsackievirus A2 (CV-A2), CV-A4 and CV-A5. For development of diagnostic reagents, for surveillance, and the development of multivalent vaccines against HFMD, the antigenicity of HFMD-associated enteroviruses warrants investigation. The purified virions of CV-A4 were inoculated into Balb/c mice and hybridomas were obtained secreting monoclonal antibodies (mAbs) directed against CV-A4 and cross-reacting with other closely related species A enteroviruses. The mAbs were characterized by ELISA, Western blotting and in vitro neutralizing assays. The majority of mAbs was non-neutralizing, with only 2% of the mAbs neutralizing CV-A4 specifically. Most of mAbs bound to linear VP1 epitopes of CV-A4. Interestingly, four types of mAbs were obtained which bound specifically to CV-A4 or were broadly to CV-A4/-A2, CV-A4/-A5 and CV-A4/-A2/-A5, respectively. Mapping with overlapping or single-amino-acid mutant peptides revealed that the four types of mAbs all bound to the first 15 amino acids at the N-terminus of the VP1. This region of picornaviruses is functionally important as it is involved in uncoating and releasing of viral RNA into the cytosol. The binding footprints of four type mAbs are composed of conserved and variable residues and are different from each other. The newly discovered broadly cross-reactive mAbs reflect the high homology of CV-A4/ CV-A2/CV-A5. The results also demonstrate that it is possible and beneficial to develop the diagnostic reagents to detect rapidly the main pathogens of enteroviruses associated with HFMD cause by CV-A4/CV-A2/CV-A5.

Polyhydroxyalkanoates: the natural biopolyester for future medical innovations.

Polyhydroxyalkanoates (PHAs) are a family of natural microbial biopolyesters with the same basic chemical structure and diverse side chain groups. Based on their excellent biodegradability, biocompatibility, thermoplastic properties and diversity, PHAs are highly promising medical biomaterials and elements of medical devices for applications in tissue engineering and drug delivery. However, due to the high cost of biotechnological production, most PHAs have yet to be applied in the clinic and have only been studied at laboratory scale. This review focuses on the biosynthesis, diversity, physical properties, biodegradability and biosafety of PHAs. We also discuss optimization strategies for improved microbial production of commercial PHAs via novel synthetic biology tools. Moreover, we also systematically summarize various medical devices based on PHAs and related design approaches for medical applications, including tissue repair and drug delivery. The main degradation product of PHAs, 3-hydroxybutyrate (3HB), is recognized as a new functional molecule for cancer therapy and immune regulation. Although PHAs still account for only a small percentage of medical polymers, up-and-coming novel medical PHA devices will enter the clinical translation stage in the next few years.

Identification of a Conserved, Linear Epitope on VP3 of Enterovirus A Species Recognized by a Broad-Spectrum Monoclonal Antibody.

Outbreaks of hand, foot and mouth disease (HFMD) have occurred frequently in the Asian-Pacific region over the last two decades, caused mainly by the serotypes in Enterovirus A species. High-quality monoclonal antibodies (mAbs) are needed to improve the accuracy and efficiency of the diagnosis of enteroviruses associated HFMD. In this study, a mAb 1A11 was generated using full particles of CV-A5 as an immunogen. In indirect immunofluorescence and Western blotting assays, 1A11 bound to the viral proteins of CV-A2, CV-A4, CV-A5, CV-A6, CV-A10, CV-A16, and EV-A71 of the Enterovirus A and targeted VP3. It has no cross-reactivity to strains of Enterovirus B and C. By mapping with over-lapped and truncated peptides, a minimal and linear epitope 23PILPGF28 was identified, located at the N-terminus of the VP3. A BLAST sequence search of the epitope in the NCBI genus Enterovirus (taxid: 12059) protein database indicates that the epitope sequence is highly conserved among the Enterovirus A species, but not among the other enterovirus species, first reported by us. By mutagenesis analysis, critical residues for 1A11 binding were identified for most serotypes of Enterovirus A. It may be useful for the development of a cost-effective and pan-Enterovirus A antigen detection for surveillance, early diagnosis and differentiation of infections caused by the Enterovirus A species.