Efficient markerless genetic manipulation of Pasteurella multocida using lacZ and pheSm as selection markers.

Pasteurella multocida is a zoonotic conditional pathogen that infects multiple livestock species, causing substantial economic losses in the animal husbandry industry. An efficient markerless method for gene manipulation may facilitate the investigations of P. multocida gene function and pathogenesis of P. multocida. Herein, a temperature-sensitive shuttle vector was constructed using lacZ as a selection marker, and markerless glgB, opa, and hyaE mutants of P. multocida were subsequently constructed through blue-white colony screening. The screening efficiency of markerless deletion strains was improved by the lacZ system, and the method could be used for multiple gene deletions. However, the fur mutant was unavailable via this method. Therefore, we constructed a pheSm screening system based on mutated phenylalanine tRNA synthetase as a counterselection marker to achieve fur deletion mutant. The transformed strain was sensitive to 20 mM p-chloro-phenylalanine, demonstrating the feasibility of pheSm as a counter-selective marker. The pheSm system was used for markerless deletions of glgB, opa, and hyaE as well as fur that could not be screened by the lacZ system. A comparison of screening efficiencies of the system showed that the pheSm counterselection system was more efficient than the lacZ system and broadly applicable for mutant screening. The methods developed herein may provide valuable tools for genetic manipulation of P. multocida.IMPORTANCEPasteurella multocida is a highly contagious zoonotic pathogen. An understanding of its underlying pathogenic mechanisms is of considerable importance and requires efficient species-specific genetic tools. Herein, we propose a screening system for P. multocida mutants using lacZ or pheSm screening markers. We evaluated the efficiencies of both systems, which were used to achieve markerless deletion of multiple genes. The results of this study support the use of lacZ or pheSm as counterselection markers to improve counterselection efficiency in P. multocida. This study provides an effective genetic tool for investigations of the virulence gene functions and pathogenic mechanisms of P. multocida.

Skin-Friendly Flexible Ultraviolet Detectors Based on Reversibly Deformable Worm-Like Polymer Nanoparticles.

Flexible ultraviolet (UV) light detection technology has important applications in wearable devices, smart sensors, and other fields and attracts much attention in recent years. However, for most semiconductor-based UV detectors, the elastic modulus between rigid semiconductors and flexible substrates is mismatched, which makes it difficult to fabricate UV detectors that meet the needs of wearable devices. Herein, a fully flexible, large-scale, skin-friendly UV photodetector component centered on photo-responsive worm-like polymer nanoparticles (NPs) is developed, and the resulting device can quantitatively detect UV illumination. Skin-friendly poly(vinyl alcohol) (PVA), amphiphilic azobenzene-containing polymer NPs (AzNPs), and water-soluble ionic liquids (IL) are formed into (AzNPs-IL)/PVA fabrics by electrospinning. There are interactions such as hydrogen bonding among PVA, AzNPs, and IL, which make the material system stable. The UV detector made of the fabric realizes UV sensing through the illuminance-mechanical stress-electrical signal conversion mechanism. It is capable of achieving a response time of 9 s, a detection range of 10-150 mW cm-2 , and stability for 1000 cycle tests upon 365 nm UV irradiation. Moreover, it has good skin affinity, and the water contact angle of the fabric is only 23.57°, which holds great promise for wearable smart devices.

Determination, temporal variation and potential health risk assessment of pesticide residues in grapes from South and Southwest China.

Pesticide residues in grapes from South and Southwest China were determined using the QuEChERS procedure and UHPLC-MS/MS and GC-MS/MS methods. The 4-year monitoring and survey showed 94.6% of the 1341 samples of grapes collected from eight main production areas contained one or multiple pesticide residues (above the respective LOQs). Overall, 40 pesticides were detected, including 24 fungicides, 12 insecticides, 2 acaricides and 2 plant growth modulators, of which one pesticide was unauthorised for use in treating grapes. Two or more pesticide residues were discovered in 87.4% of the samples (above the respective LOQs), and pesticide residues in 5.7% of the samples exceeded the MRLs, such as difenoconazole, cyhalothrin, propiconazole, etc. The main risk factors affecting the safety of grape before 2019 were difenoconazole, cyhalothrin and cyazofamid. After 2019, however, the frequency of occurrence of the above pesticides significantly declined, and the banned or restricted pesticides including omethoate were not found, which was credited to the stricter supervision and management policies by local governments. Despite the high detection rates and multi-residue occurrence of pesticides in grapes, about 84% of the samples were compliant with regulatory standards. Moreover, the accumulative chronic diet risk determined from ADI is very low. This study and timely monitoring can ensure that grape growers comply with GAP and minimise the occurrence of residues.

Mixed Selectivity Coding of Content-Temporal Detail by Dorsomedial Posterior Parietal Neurons.

The dorsomedial posterior parietal cortex (dmPPC) is part of a higher-cognition network implicated in elaborate processes underpinning memory formation, recollection, episode reconstruction, and temporal information processing. Neural coding for complex episodic processing is however under-documented. Here, we recorded extracellular neural activities from three male rhesus macaques (Macaca mulatta) and revealed a set of neural codes of "neuroethogram" in the primate parietal cortex. Analyzing neural responses in macaque dmPPC to naturalistic videos, we discovered several groups of neurons that are sensitive to different categories of ethogram items, low-level sensory features, and saccadic eye movement. We also discovered that the processing of category and feature information by these neurons is sustained by the accumulation of temporal information over a long timescale of up to 30 s, corroborating its reported long temporal receptive windows. We performed an additional behavioral experiment with additional two male rhesus macaques and found that saccade-related activities could not account for the mixed neuronal responses elicited by the video stimuli. We further observed monkeys' scan paths and gaze consistency are modulated by video content. Taken altogether, these neural findings explain how dmPPC weaves fabrics of ongoing experiences together in real time. The high dimensionality of neural representations should motivate us to shift the focus of attention from pure selectivity neurons to mixed selectivity neurons, especially in increasingly complex naturalistic task designs.

lncRNA POU6F2-AS1 Regulated by KIAA1429 Contributes to Colorectal Cancer Progression in an m6A Modification Manner.

Long non-coding RNAs (lncRNAs) are participated in tumourigenesis, including colorectal cancer (CRC). However, the effects and mechanisms of lncRNA POU6F2-AS1 in CRC have not been investigated. KIAA1429 act as a member of N6-methyladenosine (m6A) modification, has been knew as an oncogenic factor in various cancer containing CRC. We focus to investigate the regulation effect of lncRNA POU6F2-AS1, and the mechanism among lncRNA POU6F2-AS1 and KIAA1429 in CRC. The lncRNA POU6F2-AS1 and KIAA1429 levels in CRC tissue samples as well as cells were clarified by qRT-PCR, and their relationship was predicted by bioinformatics, MeRIP and Pearson analysis. Cell survival, migration and invasion were analyzed via EdU, wound healing and Transwell assays after lncRNA POU6F2-AS1 was down-regulated and KIAA1429 was up-regulated. LncRNA POU6F2-AS1 and KIAA1429 were enriched in CRC tissue samples. LncRNA POU6F2-AS1 silencing suppressed CRC cell survival, migration, and invasion, and KIAA1429 overexpression facilitated CRC cell malignancy. KIAA1429 promoted lncRNA POU6F2-AS1 expression via m6A modification. Furthermore, KIAA1429 upregulation reversed the inhibitory effect of lncRNA POU6F2-AS1 interference on the malignant behavior of CRC cells. lncRNA POU6F2-AS1 was modulated by KIAA1429 in the form of m6A modification to regulate the malignant phenotype of CRC, which may provide new insights into the potential application of KIAA1429-m6A-lncRNA POU6F2-AS1-based CRC therapy.

Cross-Modal Plasticity during Self-Motion Perception.

To maintain stable and coherent perception in an ever-changing environment, the brain needs to continuously and dynamically calibrate information from multiple sensory sources, using sensory and non-sensory information in a flexible manner. Here, we review how the vestibular and visual signals are recalibrated during self-motion perception. We illustrate two different types of recalibration: one long-term cross-modal (visual-vestibular) recalibration concerning how multisensory cues recalibrate over time in response to a constant cue discrepancy, and one rapid-term cross-modal (visual-vestibular) recalibration concerning how recent prior stimuli and choices differentially affect subsequent self-motion decisions. In addition, we highlight the neural substrates of long-term visual-vestibular recalibration, with profound differences observed in neuronal recalibration across multisensory cortical areas. We suggest that multisensory recalibration is a complex process in the brain, is modulated by many factors, and requires the coordination of many distinct cortical areas. We hope this review will shed some light on research into the neural circuits of visual-vestibular recalibration and help develop a more generalized theory for cross-modal plasticity.

Assessment of visual function in blind mice and monkeys with subretinally implanted nanowire arrays as artificial photoreceptors.

Retinal prostheses could restore image-forming vision in conditions of photoreceptor degeneration. However, contrast sensitivity and visual acuity are often insufficient. Here we report the performance, in mice and monkeys with induced photoreceptor degeneration, of subretinally implanted gold-nanoparticle-coated titania nanowire arrays providing a spatial resolution of 77.5 µm and a temporal resolution of 3.92 Hz in ex vivo retinas (as determined by patch-clamp recording of retinal ganglion cells). In blind mice, the arrays allowed for the detection of drifting gratings and flashing objects at light-intensity thresholds of 15.70-18.09 µW mm-2, and offered visual acuities of 0.3-0.4 cycles per degree, as determined by recordings of visually evoked potentials and optomotor-response tests. In monkeys, the arrays were stable for 54 weeks, allowed for the detection of a 10-µW mm-2 beam of light (0.5° in beam angle) in visually guided saccade experiments, and induced plastic changes in the primary visual cortex, as indicated by long-term in vivo calcium imaging. Nanomaterials as artificial photoreceptors may ameliorate visual deficits in patients with photoreceptor degeneration.

Comparison of the flavor qualities between two varieties of Mercenaria mercenaria.

The saltwater hard clam Mercenaria mercenaria (M. mercenaria) as a representative of low-value shellfish, enhancing its flavor quality, is the key to enter the high-end market. Nevertheless, there has not been reported research on the flavor quality of M. mercenaria. This study compared the flavor quality of selective and non-selective saltwater hard clams of M. mercenaria by using various indicators: proximate component, free amino acids, nucleotides, and metabolomic analysis. The results indicated that selective breeding contributed to the significant improvement contents of crude protein, flavor-associated free amino acids (glutamic acid, aspartic acid, proline, etc.), and nucleotides (AMP) (P < 0.05). Then, the metabolome was utilized to assess the metabolite changes in the pre/post-selective breeding of M. mercenaria and further understand the flavor characteristics and metabolic status. In the metabolomics assay, among the 3143 quantified metabolites, a total of 102 peaks were identified as significantly different metabolites (SDMs) between the selective and non-selective varieties of M. mercenaria (VIP > 1 and P < 0.05). These results can provide new insights for future research on improving the quality of saltwater bivalves through selective breeding.

Galangin Attenuates Myocardial Ischemic Reperfusion-Induced Ferroptosis by Targeting Nrf2/Gpx4 Signaling Pathway.

Purpose: Myocardial ischemic reperfusion injury (MIRI) is a crucial clinical problem globally. The molecular mechanisms of MIRI need to be fully explored to develop new therapeutic methods. Galangin (Gal), which is a natural flavonoid extracted from Alpinia Officinarum Hance and Propolis, possesses a wide range of pharmacological activities, but its effects on MIRI remain unclear. This study aimed to determine the pharmacological effects of Gal on MIRI. Methods: C57BL/6 mice underwent reperfusion for 3 h after 45 min of ischemia, and neonatal rat cardiomyocytes (NRCs) subjected to hypoxia and reoxygenation (HR) were cultured as in vivo and in vitro models. Echocardiography and TTC-Evans Blue staining were performed to evaluate the myocardial injury. Transmission electron microscope and JC-1 staining were used to validate the mitochondrial function. Additionally, Western blot detected ferroptosis markers, including Gpx4, FTH, and xCT. Results: Gal treatment alleviated cardiac myofibril damage, reduced infarction size, improved cardiac function, and prevented mitochondrial injury in mice with MIRI. Gal significantly alleviated HR-induced cell death and mitigated mitochondrial membrane potential reduction in NRCs. Furthermore, Gal significantly inhibited ferroptosis by preventing iron overload and lipid peroxidation, as well as regulating Gpx4, FTH, and xCT expression levels. Moreover, Gal up-regulated nuclear transcriptive factor Nrf2 in HR-treated NRCs. Nrf2 inhibition by Brusatol abolished the protective effect of Gal against ferroptosis. Conclusion: This study revealed that Gal alleviates myocardial ischemic reperfusion-induced ferroptosis by targeting Nrf2/Gpx4 signaling pathway.

Azobenzene-Containing Liquid Crystalline Twisted Ribbons via Polymerization-Induced Hierarchical Self-Assembly.

Polymerization-induced self-assembly incorporating liquid crystallization, as a polymerization-induced hierarchical self-assembly (PIHSA) method to produce polymeric particles with anisotropic morphologies facilely and efficiently, has drawn wide attention recently. However, the means of regulating the morphologies of liquid crystalline (LC) polymer assemblies still need to be explored. Herein, a route is presented to fabricate the twisted ribbons via PIHSA containing azobenzene based on poor reversible addition-fragmentation chain transfer (RAFT) control, called poorly controlled PIHSA. Cyano-4-(dodecylsulfanylthiocarbonyl)sulfanyl pentanoic acid-2-(2-pyridyldithio) ethyl ester is used as the RAFT agent with poor controllability, and the morphological evolution from ribbons to twisted ribbons can be observed in the corresponding PIHSA system. The formation mechanism of the twisted ribbons is studied systematically and the broad molecular weight distribution is considered to be the decisive factor. Moreover, the supramolecular chirality induced by symmetry breaking is also related to the twist of the ribbons. This study enriches the methods of controlling the morphologies of LC polymer particles and is helpful for further clarifying the mechanism of PIHSA.

Impact of migration on oral health outcomes of children in multi-beneficial kindergartens in Nanning, Southern China: a cross-sectional study.

OBJECTIVE: To explore the effect of children's migration on their oral health outcomes in multi-beneficial kindergartens in Jiangnan District, Nanning, China, and to provide a basis for improving the oral health of migrant children. METHODS: A cross-sectional study was conducted among 470 children aged 5 years in Jiangnan District, Nanning, Guangxi. A questionnaire was used to collect information on their demographic and socioeconomic background, migration experience, eating habits, oral hygiene behaviours and utilization of dental care services. Dental caries of primary teeth was examined using the decayed, missing, and filled teeth (dmft) index recommended by the World Health Organization. Dental caries experience and oral health-related behaviours were compared between migrant and resident children. The impact of children's migration attributes on their oral health outcomes was examined by univariate and multivariate analyses. RESULTS: Among the examined children, 52.3% were migrant children. The prevalence of caries among the children in multi-beneficial kindergartens was 78.3%, and the mean number of dmft was 5.73 ± 5.00. The prevalence of caries was 81.7% for migrant children and 74.6% for resident children (p = 0.060). No significant difference was found in the mean numbers of DMFT between migrant children and resident children (5.96 ± 4.81 vs. 5.47 ± 5.20, p = 0.139). There were significant differences in the frequency of tooth brushing (p = 0.023) and parental help with tooth brushing (p = 0.008), typical use of fluoride (p = 0.012), regular dental check-ups (p = 0.003) and experience of dental fillings for caries (p < 0.001) between migrant and resident children. The multivariate logistic regression analysis showed that among the children with caries, the proportion of resident children who had regular dental check-ups was 1.720 times higher than that of migrant children (95% CI = 1.155 ~ 2.560), and resident children were more likely to have caries filled than migrant children (OR = 3.313, 95% CI = 1.585 ~ 6.927). CONCLUSION: Oral health status and oral health behaviours were poor among children in multi-beneficial kindergartens in Nanning, China, and migration might be a significant predictive indicator for the poor utilization of dental care services by children. The government departments should make special policy to promote the children's oral health in multi-beneficial kindergartens, and invest more to cover the migrant children's utilization of oral health services.

The computational rules of cross-modality suppression in the visual posterior sylvian area.

The macaque visual posterior sylvian area (VPS) is an area with neurons responding selectively to heading direction in both visual and vestibular modalities, but how VPS neurons combined these two sensory signals is still unknown. In contrast to the subadditive characteristics in the medial superior temporal area (MSTd), responses in VPS were dominated by vestibular signals, with approximately a winner-take-all competition. The conditional Fisher information analysis shows that VPS neural population encodes information from distinct sensory modalities under large and small offset conditions, which differs from MSTd whose neural population contains more information about visual stimuli in both conditions. However, the combined responses of single neurons in both areas can be well fit by weighted linear sums of unimodal responses. Furthermore, a normalization model captured most vestibular and visual interaction characteristics for both VPS and MSTd, indicating the divisive normalization mechanism widely exists in the cortex.

Correlation of morphometric properties to meat yield and fatness index in the red strain of the saltwater hard clam Meretrix meretrix.

To determine the relevance of morphometric properties attributed to the meat yield and fatness index of the saltwater hard clam Meretrix meretrix. A new strain of M. meretrix with red shell color was produced after five generations of selection within a family of full-sibs. 7 morphometric traits, including shell length (SL), shell height (SH), shell width (SW), ligament length (LL), projection length (PL), projection width (PW), and live body weight (LW), and 2 meat characteristics, including meat yield (MY) and fatness index (FI) were measured from 50 individuals of three-year-old M. meretrix. The correlation coefficients, path coefficients, determination coefficients among attributes were analyzed. The results indicated that correlation achieved very significant levels (P<0.01). In addition, the multiple regression equations were formulated by considering the meat yield and fatness index as the dependent variables, respectively, and 7 other morphometric traits as independent variables. The correlation indices (R2) of morphometric traits against the meat yield and fatness index of clams were 0.901 and 0,929, respectively, indicating that the live body weight and shell length were the common main factors influencing the meat characteristics. By testing the significance of partial regression coefficient and gradually removing the non-significant morphometric traits, a multiple regression equation was established to estimate the relationship between shell length (SL, mm), live body weight (LW, g), ligament length (LL, mm) and meat yield (MY, %), fat index (FI, %): MY (%) = 0.432SL+0.251LW and FI (%) = 0.156SL+0.067LL+0.42LW-3.533. The study draws a conclusion that live body weight and shell length have a predominant direct effect on the meat yield and fatness index, which provides theoretical information for the breeding of M. meretrix.

Contrary neuronal recalibration in different multisensory cortical areas.

The adult brain demonstrates remarkable multisensory plasticity by dynamically recalibrating itself based on information from multiple sensory sources. After a systematic visual-vestibular heading offset is experienced, the unisensory perceptual estimates for subsequently presented stimuli are shifted toward each other (in opposite directions) to reduce the conflict. The neural substrate of this recalibration is unknown. Here, we recorded single-neuron activity from the dorsal medial superior temporal (MSTd), parietoinsular vestibular cortex (PIVC), and ventral intraparietal (VIP) areas in three male rhesus macaques during this visual-vestibular recalibration. Both visual and vestibular neuronal tuning curves in MSTd shifted - each according to their respective cues' perceptual shifts. Tuning of vestibular neurons in PIVC also shifted in the same direction as vestibular perceptual shifts (cells were not robustly tuned to the visual stimuli). By contrast, VIP neurons demonstrated a unique phenomenon: both vestibular and visual tuning shifted in accordance with vestibular perceptual shifts. Such that, visual tuning shifted, surprisingly, contrary to visual perceptual shifts. Therefore, while unsupervised recalibration (to reduce cue conflict) occurs in early multisensory cortices, higher-level VIP reflects only a global shift, in vestibular space.

Light-Triggered Reversible Swelling of Polymeric Spheres via Surfactant-Free RAFT Emulsion Polymerization-Induced Self-Assembly.

Responsive photonic crystals (RPCs) assembled by monodisperse colloidal particles have attracted enormous interest recently due to their tremendous applications in smart devices. Their structural colors can be determined by particle sizes. However, the lack of a reliable way to tune the sizes in situ limits their development. Herein, we present an efficient route to solve this problem through the fabrication of spherical polymeric particles with light-triggered reversible swelling behavior via surfactant-free reversible addition-fragmentation chain transfer (RAFT) emulsion polymerization-induced self-assembly (PISA). Amphiphilic macro-RAFT agents containing azobenzene groups were synthesized and subsequently employed to mediate the polymerization of methyl methacrylate. Uniform submicron spheres were obtained by modulating solid contents and other parameters. Benefiting from the photoisomerization of azobenzene moieties, the particle sizes expanded and contracted upon alternative ultraviolet/visible-light irradiation accordingly. This strategy will be a supplement to the emulsion PISA and especially give aid to the progress of the RPC materials.

Neuronal Response to Reward and Luminance in Macaque LIP During Saccadic Choice.

Recent work in decision neuroscience suggests that visual saliency can interact with reward-based choice, and the lateral intraparietal cortex (LIP) is implicated in this process. In this study, we recorded from LIP neurons while monkeys performed a two alternative choice task in which the reward and luminance associated with each offer were varied independently. We discovered that the animal's choice was dictated by the reward amount while the luminance had a marginal effect. In the LIP, neuronal activity corresponded well with the animal's choice pattern, in that a majority of reward-modulated neurons encoded the reward amount in the neuron's preferred hemifield with a positive slope. In contrast, compared to their responses to low luminance, an approximately equal proportion of luminance-sensitive neurons responded to high luminance with increased or decreased activity, leading to a much weaker population-level response. Meanwhile, in the non-preferred hemifield, the strength of encoding for reward amount and luminance was positively correlated, suggesting the integration of these two factors in the LIP. Moreover, neurons encoding reward and luminance were homogeneously distributed along the anterior-posterior axis of the LIP. Overall, our study provides further evidence supporting the neural instantiation of a priority map in the LIP in reward-based decisions.

Compound Danshen Dripping Pills pretreatment protects the heart from ischemia/reperfusion injury by enhancing autophagic flux

Abstract Compound Danshen Dripping Pills (CDDPs) have been used in clinical treatment to protect the heart from ischemia/reperfusion (IR) injury for many years. However, the underlying mechanism implicated in the protective effects remains to be explored. Here, we determined the effects of CDDPs in Sprague-Dawley rats with the IR model. Cardiac function in vivo was assessed by echocardiography. Transmission electron microscopy, histological and immunohistochemical techniques, Western blotting and recombinant adeno-associated virus 9 transfection were used to illustrate the effects of CDDPs on IR and autophagy. Our results showed that pretreatment with CDDPs decreased the level of serum myocardial enzymes and infarct size in rats after IR. Apoptosis evaluation showed that CDDPs significantly ameliorated the cardiac apoptosis level after IR. Meanwhile, CDDPs pretreatment increased myocardial autophagic flux, with upregulation of LC3B, downregulation of p62, and increased autophagosomes and autolysosomes. Moreover, the autophagic flux inhibitor chloroquine could increase IR injury, while CDDPs could partially reverse the effects. Furthermore, our results showed that the activation of AMPK/mTOR was involved in the cardioprotective effect exerted by CDDPs. Herein, we suggest that CDDPs partially protect the heart from IR injury by enhancing autophagic flux through the activation of AMPK/mTOR.

Comprehensive Analysis of Betula platyphylla Suk. PIF Gene Family and Their Potential Functions in Growth and Development.

Phytochrome-interacting factors (PIFs) are transcription factors with the basic helix-loop-helix (bHLH) domain. As integration factors between different signal pathways, members of the PIF protein family regulate many aspects of plant growth and development, such as seed germination, photomorphogenesis, thermomorphogenesis, rhythm regulation, flowering response, stomatal development, and stress responses. Our previous studies have shown that the BpSPL2 gene may regulate plants' adventitious root development through PIF genes. Within the Betula platyphylla genome, we identified eight PIF (BpPIFs) genes. We analysed and named them based on a phylogenetic tree, gene structures, and conserved motifs. Synteny analysis indicated that transposition or segmental duplication events played a minor role in the expansion of BpPIFs. The comparative syntenic analysis combined with phylogenetic analysis provided a deep insight into the phylogenetic relationships of BpPIF genes, suggesting that BpPIF proteins are closer to PtPIF than to AtPIF. The analysis of cis-acting elements in promoter regions of BpPIF genes indicated that various elements were related to light, abiotic stress, and plant hormone responsiveness. In addition, we found that these promoters have the transcription factor of B. platyphylla SPL2 (BpSPL2) binding motif GTAC. Expression analysis demonstrated that BpPIF genes, especially BpPIF4, BpPIF9b, and BpPIF10, might be the potential target genes of BpSPL2 in the process of adventitious root formation. Besides providing a comprehensive understanding of the BpPIF family, we propose a hypothetical gene network regulatory model for adventitious root formation.

The rs35874116 single nucleotide polymorphism increases sweet intake and the risk of severe early childhood caries: a case-control study.

BACKGROUND: Dental caries is one of the most prevalent chronic diseases worldwide among children. The rs35874116 single nucleotide polymorphism (SNP) in the sweet receptor gene TAS1R2 has been associated with dental caries at a high risk in permanent teeth among school children and adults. To date, little is known about the association of this SNP with sweet intake and caries risk in the primary school children. METHODS: Total of 236 children were included, namely 118 subjects in the non-caries (NC) group and severe early childhood caries (S-ECC) group, respectively. Oral mucosa cells were collected from all the selected children, and the full length of exon 3 in TAS1R2 was sequenced to analyse rs35874116 polymorphism. A questionnaire was used to collect information about socio-demographic information, frequency of sweet intake and oral hygiene habits. Multiple logistic regression models were applied to assess the relationship of rs35874116 polymorphism with frequency of sweet intake and S-ECC among the five-year-old children. RESULTS: Children with the TT genotype of rs35874116 had a higher frequency of sweet intake than CT/CC carriers (51.3% vs. 32.7%; x2 = 5.436, p = 0.020), and S-ECC individuals were more likely to be TT genotype carriers than NC individuals (53.5% vs. 46.5%; x2 = 4.353, p = 0.037). Multiple logistic regression analyses showed that the TT genotype of rs35874116 was not only significantly related to the frequency of sweet intake (OR = 2.25, 95% CI = 1.14-4.44) but also significantly associated with S-ECC (OR = 2.11, 95% CI = 1.01 ~ 4.42). CONCLUSIONS: The rs35874116 polymorphism might increase sweet intake and the risk of S-ECC among five-year-old children in Nanning, China.

Seed-mediated in situ growth of photothermal reagent gold nanostars: Mechanism study and preliminary assay application.

Photothermal reagent-mediated portable detection platforms using thermometers as signal readers have received extensive attention due to their simplicity, low cost, and practicality. However, exploitation photothermal reagent with excellent photothermal conversion effect, convenient to synthesize, preferably without any modification for biosensing application, is still challenging. Herein, a simple and rapid seed-mediated in situ synthesis strategy has been developed for the preparation of gold nanostars (AuNSs) with remarkable photothermal conversion effect. By simply changing the seed size and component concentrations involved in the in situ synthesis process, AuNSs have adjustable geometries, allowing the photothermal conversion to be tuned to a high level optimal for biosensing. Meanwhile, an accurate understanding of the photothermal conversion mechanism is obtained by studying the relationship between the morphology of AuNSs and the photothermal effect. Subsequently, using ascorbic acid (AA) as a model target, the preliminary application of AuNSs in constructing a portable photothermal detection platform has been demonstrated. This in situ preparation strategy of AuNSs not only exhibits remarkable photothermal conversion effect, but also avoids complicated and time-consuming synthesis and modification. Therefore, it has great potential to be extended to portable detection of other targets by simply converting the concentration of the target to that of AA.