Change in oral health-related behaviours of children before and after dental treatments under general anaesthesia.

This study evaluated the behavioural changes pertaining to children's oral health before and after the dental general anaesthesia (DGA), with particular focus on the factors associated with these changes. The records were collected for the children who received DGA from July 2015 to November 2016, and relevant questionnaires were obtained from their parents/guardians for the information prior to and after the DGA. The questionnaire included Early Childhood Oral Health Impact Scale (ECOHIS) and Dental Subscale of Children's Fear Survey Schedule (CFSS-DS) to investigate the changes in Oral Health-related Quality of Life (OHRQoL) and dental fear. The DGA impact on children's oral hygiene habits and oral health-related behaviours was assessed by analysing the data. The chi-square test and Mann-Whitney test were employed to evaluate the differences. Total of 141 patients (89 before DGA and 77 after DGA, 25 being common) participated in this study. There were 60 children below 5 years and 29 over 5 years before DGA, while 41 children below 5 years and 36 over 5 years after DGA. Most parents/guardians were educated above undergraduate level (59.6% before DGA, 55.8% after DGA). More children lived with grandparents (61.8% before DGA, 54.5% after DGA) than only with parents (20.2% before DGA, 26.0% after DGA). In total, 73.0% (65/89) children before DGA brushed teeth more than twice a day. This proportion increased to 90.9% after DGA (70/77, p = 0.03). The eating difficulty decreased after DGA according to ECOHIS (p = 0.01). CFSS-DS score also decreased after DGA (p < 0.05). After DGA, children's oral hygiene habits and oral health-related quality of life (OHRQoL) improved, children fear for dental treatment decreased, and parents became more attentive towards children oral health.

A novel radiomics-based technique for identifying vulnerable coronary plaques: a follow-up study.

BACKGROUND: Previous reports have suggested that coronary computed tomography angiography (CCTA)-based radiomics analysis is a potentially helpful tool for assessing vulnerable plaques. We aimed to investigate whether coronary radiomic analysis of CCTA images could identify vulnerable plaques in patients with stable angina pectoris. METHODS: This retrospective study included patients initially diagnosed with stable angina pectoris. Patients were randomly divided into either the training or test dataset at an 8 : 2 ratio. Radiomics features were extracted from CCTA images. Radiomics models for predicting vulnerable plaques were developed using the support vector machine (SVM) algorithm. The model performance was assessed using the area under the curve (AUC); the accuracy, sensitivity, and specificity were calculated to compare the diagnostic performance using the two cohorts. RESULTS: A total of 158 patients were included in the analysis. The SVM radiomics model performed well in predicting vulnerable plaques, with AUC values of 0.977 and 0.875 for the training and test cohorts, respectively. With optimal cutoff values, the radiomics model showed accuracies of 0.91 and 0.882 in the training and test cohorts, respectively. CONCLUSION: Although further larger population studies are necessary, this novel CCTA radiomics model may identify vulnerable plaques in patients with stable angina pectoris.

Identification of toll-like receptor 2 as a key regulator of neuronal apoptosis in vascular dementia by bioinformatics analysis and experimental validation.

BACKGROUND: Vascular dementia (VaD), the second most prevalent type of dementia, lacks a well-defined cause and effective treatment. Our objective was to utilize bioinformatics analysis to discover the fundamental disease-causing genes and pathological mechanisms in individuals diagnosed with VaD. METHODS: To identify potential pathogenic genes associated with VaD, we conducted weighted gene co-expression network analysis (WGCNA), differential expression analysis, and protein-protein interaction (PPI) analysis. The exploration of potential biological mechanisms involved the utilization of Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analysis. Moreover, a bilateral common carotid artery stenosis (BCAS) mouse model of VaD was established, and the expression of the hub gene, its relationship with cognitive function and its potential pathogenic mechanism were verified by cognitive behavior tests, cerebral blood flow measurement, Western blotting, and immunofluorescence experiments. RESULTS: This study identified 293 DEGs from the brain cortex of VaD patients and healthy controls, among these genes, the Toll-like receptor 2 (TLR2) gene was identified as hub gene, and it was associated with the apoptosis-related pathway PI3K/AKT.The BCAS model demonstrated that the use of TLR2 inhibitors greatly enhanced the cognitive function of the mice (p < 0.05). Additionally, there was a notable decrease in the number of apoptotic cells in the brain cortex of the mice (p < 0.01). Moreover, significant alterations in the levels of proteins related to the PI3K/AKT pathway and cleaved-caspase3 proteins were detected (p < 0.05). CONCLUSIONS: TLR2 plays a role in the pathophysiology of VaD by enhancing the neuronal apoptotic pathway, suggesting it could be a promising therapeutic target.

Dietary emulsifier polysorbate 80 exposure accelerates age-related cognitive decline.

Gut microbial homeostasis is crucial for the health of cognition in elderly. Previous study revealed that polysorbate 80 (P80) as a widely used emulsifier in food industries and pharmaceutical formulations could directly alter the human gut microbiota compositions. However, whether long-term exposure to P80 could accelerate age-related cognitive decline via gut-brain axis is still unknown. Accordingly, in this study, we used the senescence accelerated mouse prone 8 (SAMP8) mouse model to investigate the effects of the emulsifier P80 intake (1 % P80 in drinking water for 12 weeks) on gut microbiota and cognitive function. Our results indicated that P80 intake significantly exacerbated cognitive decline in SAMP8 mice, along with increased brain pathological proteins deposition, disruption of the blood-brain barrier and activation of microglia and neurotoxic astrocytes. Besides, P80 intake could also induce gut microbiota dysbiosis, especially the increased abundance of secondary bile acids producing bacteria, such as Ruminococcaceae, Lachnospiraceae, and Clostridium scindens. Moreover, fecal microbiota transplantation from P80 mice into 16-week-old SAMP8 mice could also exacerbated cognitive decline, microglia activation and intestinal barrier impairment. Intriguingly, the alterations of gut microbial composition significantly affected bile acid metabolism profiles after P80 exposure, with markedly elevated levels of deoxycholic acid (DCA) in serum and brain tissue. Mechanically, DCA could activate microglial and promote senescence-associated secretory phenotype production through adenosine triphosphate-binding cassette transporter A1 (ABCA1) importing lysosomal cholesterol. Altogether, the emulsifier P80 accelerated cognitive decline of aging mice by inducing gut dysbiosis, bile acid metabolism alteration, intestinal barrier and blood brain barrier disruption as well as neuroinflammation. This study provides strong evidence that dietary-induced gut microbiota dysbiosis may be a risk factor for age-related cognitive decline.

CSF1R blockade slows progression of cerebral hemorrhage by reducing microglial proliferation and increasing infiltration of CD8 + CD122+ T cells into the brain.

Microglia play a pivotal role in the neuroinflammatory response after brain injury, and their proliferation is dependent on colony-stimulating factors. In the present study, we investigated the effect of inhibiting microglia proliferation on neurological damage post intracerebral hemorrhage (ICH) in a mouse model, an aspect that has never been studied before. Using a colony-stimulating factor-1 receptor antagonist (GW2580), we observed that inhibition of microglia proliferation significantly ameliorated neurobehavioral deficits, attenuated cerebral edema, and reduced hematoma volume after ICH. This intervention was associated with a decrease in pro-inflammatory factors in microglia and an increased infiltration of peripheral regulatory CD8 + CD122+ T cells into the injured brain tissue. The CXCR3/CXCL10 axis is the mechanism of brain homing of regulatory CD8 + CD122+ T cells, and the high expression of IL-10 is the hallmark of their synergistic anti-inflammatory effect with microglia. And activated astrocytes around the insult site are a prominent source of CXCL10. Thus, inhibition of microglial proliferation offers a new perspective for clinical translation. The cross-talk between multiple cells involved in the regulation of the inflammatory response highlights the comprehensive nature of neuroimmunomodulation.

Exosomes derived from microglia overexpressing miR-124-3p alleviate neuronal endoplasmic reticulum stress damage after repetitive mild traumatic brain injury.

JOURNAL/nrgr/04.03/01300535-202409000-00033/figure1/v/2024-01-16T170235Z/r/image-tiff We previously reported that miR-124-3p is markedly upregulated in microglia-derived exosomes following repetitive mild traumatic brain injury. However, its impact on neuronal endoplasmic reticulum stress following repetitive mild traumatic brain injury remains unclear. In this study, we first used an HT22 scratch injury model to mimic traumatic brain injury, then co-cultured the HT22 cells with BV2 microglia expressing high levels of miR-124-3p. We found that exosomes containing high levels of miR-124-3p attenuated apoptosis and endoplasmic reticulum stress. Furthermore, luciferase reporter assay analysis confirmed that miR-124-3p bound specifically to the endoplasmic reticulum stress-related protein IRE1α, while an IRE1α functional salvage experiment confirmed that miR-124-3p targeted IRE1α and reduced its expression, thereby inhibiting endoplasmic reticulum stress in injured neurons. Finally, we delivered microglia-derived exosomes containing miR-124-3p intranasally to a mouse model of repetitive mild traumatic brain injury and found that endoplasmic reticulum stress and apoptosis levels in hippocampal neurons were significantly reduced. These findings suggest that, after repetitive mild traumatic brain injury, miR-124-3 can be transferred from microglia-derived exosomes to injured neurons, where it exerts a neuroprotective effect by inhibiting endoplasmic reticulum stress. Therefore, microglia-derived exosomes containing miR-124-3p may represent a novel therapeutic strategy for repetitive mild traumatic brain injury.

Stimuli-responsive incremental DNA machine auto-catalyzed CRISPR-Cas12a feedback amplification permits ultrasensitive molecular diagnosis of esophageal cancer-related microRNA.

Development of new diagnostic methods is essential for disease diagnosis and treatment. In this work, we present a stimuli-responsive incremental DNA machine auto-catalyzed CRISPR-Cas12a (SRI-DNA machine/CRISPR-Cas12a) feedback amplification for ultrasensitive molecular detection of miRNA-21, which is an important biomarker related closely to the initiation and development of cancers, such as esophageal cancer. Strategically, the powerful SRI-DNA machine and efficient trans-cleavage activity of the CRISPR-Cas12a system are ingeniously integrated via a rationally designed probe termed as stem-elongated functional hairpin probe (SEF-HP). The SRI-DNA machine begins with the target miRNA, the trigger of the reaction, binding complementarily to the SEF-HP, followed by autonomously performed mechanical strand replication, cleavage, and displacement circuit at multiple sites. This conversion process led to the amplified generation of numerous DNA activators that are complementary with CRISPR RNA (CrRNA). Once formed the DNA activator/CrRNA heteroduplex, the trans-cleavage activity of the CRISPR-Cas12a was activated to nonspecific cleavage of single-stranded areas of a reporter probe for fluorescence emission. Under optimal conditions, the target miRNA can be detected with a wide linear range and an excellent specificity. As a proof-of-concept, this SRI-DNA machine/CRISPR-Cas12a feedback amplification system is adaptable and scalable to higher-order artificial amplification circuits for biomarkers detection, highlighting its promising potential in early diagnosis and disease treatment.

Effect of short neuropeptide F signaling on larval feeding in Mythimna separata.

Mythimna separata is a notorious phytophagous pest which poses serious threats to cereal crops owing to the gluttony of the larvae. Because short neuropeptide F (sNPF) and its receptor sNPFR are involved in a diversity of physiological functions, especially in functions related to feeding in insects, it is a molecular target for pest control. Herein, an sNPF and 2 sNPFRs were identified and cloned from M. separata. Bioinformatics analysis revealed that the sNPF and its receptors had a highly conserved RLRFamide C-terminus and 7 transmembrane domains, respectively. The sNPF and its receptor genes were distributed across larval periods and tissues, but 2 receptors had distinct expression patterns. The starvation-induced assay elucidated that sNPF and sNPFR expression levels were downregulated under food deprivation and recovered with subsequent re-feeding. RNA interference knockdown of sNPF, sNPFR1, and sNPFR2 by injection of double-stranded RNA into larvae not only suppressed food consumption and increased body size and weight, but also led to decrease of glycogen and total lipid contents, and increase of trehalose compared with double-stranded green fluorescent protein injection. Furthermore, molecular docking was performed on the interaction mode between sNPFR protein and its ligand sNPF based on the 3-dimensional models constructed by AlphaFold; the results indicated that both receptors were presumably activated by the mature peptide sNPF-2. These results revealed that sNPF signaling played a considerably vital role in the feeding regulation of M. separata and represents a potential control target for this pest.

Toward Reagent-Free Discrimination of Alzheimer's Disease Using Blood Plasma Spectral Digital Biomarkers and Machine Learning.

BACKGROUND: Alzheimer's disease (AD) is the most prevalent neurodegenerative disease. The detection of early-stage AD is particularly desirable because it would allow early intervention. However, a minimally invasive, low-cost, and accurate discrimination or diagnostic method for AD is especially difficult in the earliest stage of AD. OBJECTIVE: The aim of this research is to discover blood plasma spectral digital biomarkers of AD, develop a novel intelligent method for the discrimination of AD and accelerate the translation of Fourier transform infrared (FTIR) spectral-based disease discrimination methods from the laboratory to clinical practice. METHODS: Since vibration spectroscopy can provide the structure and chemical composition information of biological samples at the molecular level, we investigated the potential of FTIR spectral biomarkers of blood plasma to differentiate between AD patients and healthy controls. Combined with machine learning technology, we designed a hierarchical discrimination system that provides reagent-free and accurate AD discrimination based on blood plasma spectral digital biomarkers of AD. RESULTS: Accurate segregation between AD patients and healthy controls was achieved with 89.3% sensitivity and 85.7% specificity for early-stage AD patients, 92.8% sensitivity and 87.5% specificity for middle-stage AD patients, and 100% sensitivity and 100% specificity for late-stage AD patients. CONCLUSIONS: Our results show that blood plasma spectral digital biomarkers hold great promise as discrimination markers of AD, indicating the potential for the development of an inexpensive, reagent-free, and less laborious clinical test. As a result, our research outcome will accelerate the clinical application of spectral digital biomarkers and machine learning.

Intranasal Delivery of Gene-Edited Microglial Exosomes Improves Neurological Outcomes after Intracerebral Hemorrhage by Regulating Neuroinflammation.

Neural inflammatory response is a crucial pathological change in intracerebral hemorrhage (ICH) which accelerates the formation of perihematomal edema and aggravates neural cell death. Although surgical and drug treatments for ICH have advanced rapidly in recent years, therapeutic strategies that target and control neuroinflammation are still limited. Exosomes are important carriers for information transfer among cells. They have also been regarded as a promising therapeutic tool in translational medicine, with low immunogenicity, high penetration through the blood-brain barrier, and ease of modification. In our previous research, we have found that exogenous administration of miRNA-124-overexpressed microglial exosomes (Exo-124) are effective in improving post-injury cognitive impairment. From this, we evaluated the potential therapeutic effects of miRNA-124-enriched microglial exosomes on the ICH mice in the present study. We found that the gene-edited exosomes could attenuate neuro-deficits and brain edema, improve blood-brain barrier integrity, and reduce neural cell death. Moreover, the protective effect of Exo-124 was abolished in mice depleted of Gr-1+ myeloid cells. It suggested that the exosomes exerted their functions by limiting the infiltration of leukocyte into the brain, thus controlling neuroinflammation following the onset of ICH. In conclusion, our findings provided a promising therapeutic strategy for improving neuroinflammation in ICH. It also opens a new avenue for intranasal delivery of exosome therapy using miRNA-edited microglial exosomes.

Revisiting the genetic diversity and population structure of the endangered Green Sea Turtle (Chelonia mydas) breeding populations in the Xisha (Paracel) Islands, South China Sea.

The Green Sea Turtle (Chelonia mydas) is an umbrella species in the South China Sea, a Chinese national first-level protected wild animal, and the only sea turtle that nests in waters around China. The largest C. mydas nesting ground is distributed in the Xisha (Paracel) Islands, which plays a vital role in the survival of sea turtle populations in the region. This study reveals the genetic diversity and population structure of the breeding population of C. mydas in the Xisha (Paracel) Islands using three mitochondrial markers. A total of 15 D-loop, five Cytochrome b (Cyt b), and seven Cytochrome C Oxidase subunit I (COI) haplotypes were identified in the breeding population of C. mydas in the Xisha (Paracel) Islands. D-loop haplotypes are distributed in clades III, IV, and VIII of the C. mydas mitochondrial control region. It is the first time that one haplotype from Clade IV was found in this C. mydas population, and five new D-loop haplotypes were also identified. The haplotype and nucleotide diversity were calculated for each marker: D-loop (0.415 haplotype diversity, 0.00204 nucleotide diversity), Cyt b (0.140, 0.00038) and COI (0.308, 0.00083). The average genetic distance (p) of each molecular marker was less than 0.01. Neutral detection and nucleotide mismatch analysis suggested that the breeding population of C. mydas in the Xisha (Paracel) Islands did not experience a population expansion event in recent history. It is recommended that a sea turtle protection area be established in the Xisha (Paracel) Islands area to strengthen protection and effectively protect the uniqueness and sustainability of the breeding population of C. mydas in the South China Sea.

The design and clinical application of a new appliance to treat impacted maxillary central incisors.

Maxillary central incisor impaction is one of the most common types of dental anomalies in children. Treatment of impacted central incisors is complicated and challenging given the position of the impacted central incisors, root development, and the complexity of the crown eruption direction. This study aimed to describe the use of a new multifunctional appliance for the treatment of impacted maxillary central incisors. This article reports the use of a novel appliance for the treatment of impacted maxillary central incisors. We describe the cases of two young patients with labial horizontally impacted maxillary central incisors. Both patients were treated using this novel appliance. Therapeutic effects were evaluated by comparing the pretreatment results, posttreatment cone-beam computed tomography images, and posttreatment clinical examination results. At the end of the treatment period using the novel appliance, the impacted central incisors had successfully been properly aligned in the dental arch, and the tooth roots had not resorbed. Both patients exhibited good dental alignment, with restored function and acceptable aesthetics. This article demonstrates that the new appliance was comfortable, convenient, safe, and effective in the treatment of impacted maxillary central incisors and that its clinical use should be promoted in the future.

Investigation on beach debris on the historical nesting grounds of green turtles (Chelonia mydas) in Hainan Island, South China.

Hainan Island used to be the most important nesting ground of green turtles in China before they disappeared about 37 years ago. Habitat degradation is one of the main reasons for the disappearance of sea turtles. Therefore, it is necessary to take action to evaluate and recover the historical nesting grounds if we hope for sea turtles to return in the future. In this study, we surveyed the beach debris on 13 historical nesting grounds of green sea turtles on Hainan Island. The beach debris on these nesting grounds mainly consisted of plastic, cigarette butts, foam, glass, and nylon, with plastic (including plastic blocks, cigarette butts, and foam) being the dominant type, accounting for 78.92% in number, followed by glass. The average density of beach debris was 0.314 pieces·m-2. Compared to other nesting grounds, the average quantity and density of beach debris in Hainan was lower, but the proportion of plastic debris was extremely high. After categorizing debris type, we found that most was from human coastal activities (35.54%), with debris at tourist beaches having the biggest proportion of debris from smoking supplies. The distribution characteristics of beach debris were related to the function of the beach, density of tourist, and the intensity of beach debris cleaning. It is recommended to further strengthen the emission reduction and clean-up of beach debris in Hainan Island, so as to restore the nesting habitat of sea turtles as soon as possible.

The ecdysis triggering hormone system is essential for reproductive success in Mythimna separata (Walker).

Ecdysis triggering hormone (ETH) was originally discovered as a key hormone that regulates insect moulting via binding to its receptor, ETH receptor (ETHR). However, the precise role of ETH in moth reproduction remains to be explored in detail. ETH function was verified in vivo using Mythimna separata (Walker), an important cereal crop pest. RT-qPCR analysis revealed that transcriptional expression profiles of MsepETH showed evident sexual dimorphism in the adult stage. MsepETH expression increased in the females on day 3 and persisted thereafter till day 7, consistent with female ovarian maturation, and was merely detectable in males. Meanwhile, MsepETH expression levels were significantly higher in the trachea than in other tissues. MsepETHR-A and MsepETHR-B were expressed in both sexes and were significantly higher in the antennae than in other tissues. MsepETH and MsepETHR knockdown in females by RNA interference significantly reduced the expression of MsepETH, MsepETHR-A, MsepETHR-B, MsepJHAMT, and MsepVG, which delayed egg-laying and significantly reduced egg production. RNAi 20-hydroxyecdysone (20E) receptor (EcR) decreased MsepETH expression whereas injecting 20E restored egg production that had been disrupted by MsepETH interference. Meanwhile, RNAi juvenile hormone (JH) methoprene tolerant protein (Met) also decreased MsepETH expression and smearing JH analog methoprene (Meth) restored egg production. In conclusion, the reproduction roles of ETH, JH, and 20E were investigated in M. separata. These findings will lay the foundation for future research to develop an antagonist that reduces female reproduction and control strategies for pest insects.

GDNF-Loaded Polydopamine Nanoparticles-Based Anisotropic Scaffolds Promote Spinal Cord Repair by Modulating Inhibitory Microenvironment.

Spinal cord injury (SCI) is a devastating injury that causes permanent loss of sensation and motor function. SCI repair is a significant challenge due to the limited regenerating ability of adult neurons and the complex inflammatory microenvironment. After SCI, the oxidative stress induced by excessive reactive oxygen species (ROS) often leads to prolonged neuroinflammation that results in sustained damage to the spinal cord tissue. Polydopamine (PDA) shows remarkable capability in scavenging ROS to treat numerous inflammatory diseases. In this study, glial cell-derived neurotrophic factor (GDNF)-loaded PDA nanoparticle-based anisotropic scaffolds for spinal cord repair are developed. It is found that mesoporous PDA nanoparticles (mPDA NPs) in the scaffolds efficiently scavenge ROS and promote microglia M2 polarization, thereby inhibiting inflammatory response at the injury site and providing a favorable microenvironment for nerve cell survival. Furthermore, the GDNF encapsulated in mPDA NPs promotes corticospinal tract motor axon regeneration and its locomotor functional recovery. Together, findings from this study reveal that the GDNF-loaded PDA/Gelatin scaffolds hold potential as an effective artificial transplantation material for SCI treatment.

Identification of the neuropeptide gene family and feeding regulation by neuropeptide Y in Mythimna separata (Lepidoptera: Noctuidae).

Mythimna separata is a crucial agricultural pest with polyphagous characteristic. Neuropeptide signaling, especially neuropeptide Y (NPY) involved in feeding regulation, is considered as a potential pest control target. In this study, we identified 50 neuropeptides including NPY of M. separata using transcriptome sequencing. Bioinformatics analysis showed that NPY had a conserved carboxyterminal motif of RGRYamide and shared very high homology across lepidopteran insects. Spatio-temporal expression profile articulated that NPY was mainly expressed in the larval stage, and with the highest expression in larval midgut and adult alimentary canal. RNAi knockdown by the injection of dsNPY into larvae significantly inhibited food uptake and body weight, delayed developmental duration, and also caused increase of trehalose and decrease of glycogen and total lipid compared to dsGFP. This study identified nearly the entire neuropeptide gene family of M. separata and further indicated that NPY signaling pathway might played a vital role in the feeding regulation and related to energy metabolism. Our results not only laid a preliminary foundation for functional studies on neuropeptide of M. separata, but also provided a potential molecular target for future pesticide development.

Nanoscale coordination polymer Fe-DMY downregulating Poldip2-Nox4-H2O2 pathway and alleviating diabetic retinopathy.

Diabetic retinopathy (DR) is a prevalent microvascular complication of diabetes and the leading cause of blindness and severe visual impairment in adults. The high levels of glucose trigger multiple intracellular oxidative stress pathways, such as POLDIP2, resulting in excessive reactive oxygen species (ROS) production and increased expression of vascular cell adhesion molecule-1 (VCAM-1), hypoxia-inducible factor 1α (HIF-1α), and vascular endothelial growth factor (VEGF), causing microvascular dysfunction. Dihydromyricetin (DMY) is a natural flavonoid small molecule antioxidant. However, it exhibits poor solubility in physiological environments, has a short half-life in vivo, and has low oral bioavailability. In this study, we present, for the first time, the synthesis of ultra-small Fe-DMY nano-coordinated polymer particles (Fe-DMY NCPs), formed by combining DMY with low-toxicity iron ions. In vitro and in vivo experiments confirm that Fe-DMY NCPs alleviate oxidative stress-induced damage to vascular endothelial cells by high glucose, scavenge excess ROS, and improve pathological features of DR, such as retinal vascular leakage and neovascularization. Mechanistic validation indicates that Fe-DMY NCPs can inhibit the activation of the Poldip2-Nox4-H2O2 signaling pathway and downregulate vital vascular function indicators such as VCAM-1, HIF-1α, and VEGF. These findings suggest that Fe-DMY NCPs could serve as a safe and effective antioxidant and microangio-protective agent, with the potential as a novel multimeric drug for DR therapy.

[Bacteriostasis of Platelet-Rich Plasma and Its Derivatives in Vitro and Its Relationship with PF4].

OBJECTIVE: To investigate the bacteriostatic effect of platelet-rich plasma (PRP) and its derivative platelet gel (PG) supernatant on Escherichia coli in vitro and its relationship with platelet factor 4 (PF4). METHODS: Apheresis platelets donated by healthy volunteers were obtained from the Blood station of Lu an Blood Center as the source of PRP. The counts of platelet, white blood cell and red blood cell in PRP and its derivative PG supernatant were detected by automatic hematology analyzer. Bacterial growth of PRP and PG supernatants co-cultured with bacteria for different time was observed by plate coating culture method, and the contents of PF4 in PRP and PG supernatants were detected by ELISA. RESULTS: Apheresis platelets were collected from 28 healthy volunteers with a median age of 33 (21-56) years old. PRP can inhibit the growth of escherichia coli, but there were individual differences in antibacterial effect within 24 hours. PRP of 13 healthy volunteers had strong antibacterial effect at 24 hours, 7 cases had weak antibacterial effect at 24 hours, and 8 cases had no antibacterial effect at 24 hours. PG supernatant showed no significant individual difference, and all of them had bacteriostatic effect within 12 hours, but no bacteriostatic effect after 12 hours. There was no statistical difference in the bacteriostatic effect of PRP at 24 hours between healthy volunteers aged ≤30 years and >30 years (P>0.05), and there was no statistical difference between the white blood cell count ≤0.1×109/L and (0.1-1) ×109/L groups (P>0.05). There was significant difference in the bacteriostatic effect of PRP between the two groups with platelet content ≤1 000×109/L and >1 000×109/L (P<0.05). The platelet count in PRP was higher than that in PG supernatant ï¼»(911.57±160.52) ×109/L vs 0ï¼½. The PF4 level in PRP was higher than that in PG supernatant (23623.34±9822.14 vs 6664.74±4065.83, P<0.05). CONCLUSION: Both PRP and PG supernatant have antibacterial effects in Escherichia coli. The bacteriostatic effect of PRP was better than that of PG supernatant, and the platelet and PF4 contents in PRP were higher than those in PG supernatant, suggesting that the platelet and PF4 levels play an important role in bacteriostasis.