Bone marrow mesenchymal stem cell-derived exosomes loaded with miR-26a through the novel immunomodulatory peptide DP7-C can promote osteogenesis.

PURPOSE: As small bioactive molecules, exosomes can deliver osteogenesis-related miRNAs to target cells and promote osteogenesis. This study aimed to investigate miR-26a as a therapeutic cargo to be loaded into bone marrow stromal cell exosomes through a novel immunomodulatory peptide (DP7-C). METHODS: After transfecting BMSCs with DP7-C as a transfection agent, exosomes were extracted by ultracentrifugation from the culture supernatant of miR-26a-modified BMSCs. We then characterized and identified the engineered exosomes. The effect of the engineered exosomes on osteogenesis was then evaluated in vitro and in vivo, including transwell, wound healing, modified alizarin red staining, western blot, real-time quantitative PCR, and experimental periodontitis assays. Bioinformatics and data analyses were conducted to investigate the role of miR-26a in bone regeneration. RESULTS: The DP7-C/miR-26a complex successfully transfected miR-26a into BMSCs and stimulated them to release more than 300 times the amount of exosomes overexpressing miR-26a compared with the ExoNC group. Furthermore, exosomes loaded with miR-26a could enhance proliferation, migration, and osteogenic differentiation of BMSCs in vitro compared with the ExoNC and blank groups. In vivo, the ExomiR-26a group inhibited the destruction of periodontitis compared with the ExoNC and blank groups, as revealed by HE staining. Micro-CT indicated that treatment of ExomiR-26a increased the percent bone volume and the bone mineral density compared with those of the ExoNC (P < 0.05) and blank groups (P < 0.001). Target gene analysis indicated that the osteogenic effect of miR-26a is related to the mTOR pathway. CONCLUSION: miR-26a can be encapsulated into exosomes through DP7-C. Exosomes loaded with miR-26a can promote osteogenesis and inhibit bone loss in experimental periodontitis and serve as the foundation for a novel treatment strategy.

Exploring the Potential of Big Data Analytics in Urban Epidemiology Control: A Comprehensive Study Using CiteSpace.

In recent years, there has been a growing amount of discussion on the use of big data to prevent and treat pandemics. The current research aimed to use CiteSpace (CS) visual analysis to uncover research and development trends, to help academics decide on future research and to create a framework for enterprises and organizations in order to plan for the growth of big data-based epidemic control. First, a total of 202 original papers were retrieved from Web of Science (WOS) using a complete list and analyzed using CS scientometric software. The CS parameters included the date range (from 2011 to 2022, a 1-year slice for co-authorship as well as for the co-accordance assessment), visualization (to show the fully integrated networks), specific selection criteria (the top 20 percent), node form (author, institution, region, reference cited, referred author, journal, and keywords), and pruning (pathfinder, slicing network). Lastly, the correlation of data was explored and the findings of the visualization analysis of big data pandemic control research were presented. According to the findings, "COVID-19 infection" was the hottest cluster with 31 references in 2020, while "Internet of things (IoT) platform and unified health algorithm" was the emerging research topic with 15 citations. "Influenza, internet, China, human mobility, and province" were the emerging keywords in the year 2021-2022 with strength of 1.61 to 1.2. The Chinese Academy of Sciences was the top institution, which collaborated with 15 other organizations. Qadri and Wilson were the top authors in this field. The Lancet journal accepted the most papers in this field, while the United States, China, and Europe accounted for the bulk of articles in this research. The research showed how big data may help us to better understand and control pandemics.

Lycium barbarum polysaccharide-glycoprotein promotes osteogenesis in hPDLSCs via ERK activation.

OBJECTIVE: A lack of relevant research on Lycium barbarum polysaccharide-glycoprotein (LBP) application in oral diseases. Here, we focused on the effect of LBP on osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) and periodontitis bone loss. METHODS: Human periodontal ligament stem cells (hPDLSCs) were isolated and identified by flow cytometry. Alkaline phosphatase (ALP) activity, Alizarin Red staining, and combined qPCR and Western blot analyses were performed to elucidate the effects of LBP on the osteogenic potential of hPDLSCs. In vivo experiments were performed with the treatment of LBP in rat periodontal model. MicroCT scanning and histological analysis were conducted to evaluate osteogenesis in situ. RESULTS: Human periodontal ligament stem cells (hPDLSCs) were successfully isolated and identified with CD90, CD29, and CD45. LBP enhanced hPDLSCs proliferation and migration and promoted RUNX2, ALP, Collagen I, and Osteocalcin expression through activating the ERK1/2 signaling pathway in vitro. The inflammatory factors, including interleukin 6 (IL-6) and interleukin 8 (IL-8) were reduced after LBP treatment. Alveolar bone resorption was significantly decreased in the LBP-treated groups in vivo, and osteoclast was markedly decreased by LBP application. CONCLUSION: LBP promoted hPDLSC osteogenesis by targeting the ERK1/2 signaling pathway and reverse bone loss by reducing inflammation. These findings provided latent hope for LBP application in periodontal therapy.

HTRA1 rs11528744, BCRA1 rs9928736, and B3GLCT rs4381465 are associated with age-related macular degeneration in a Chinese population.

Purpose: Age-related macular degeneration (AMD) is a leading cause of vision loss. A Previous study based on the co-localization analysis of the genome-wide association study (GWAS) and eQTL genetic signals have reported that single nucleotide polymorphisms (SNPs), including rs760975, rs11528744, rs3761159, rs7212510, rs6965458, rs7559693, rs56108400, rs28495773, rs9928736, rs11777697, rs4381465 are associated with AMD in Americans. The aim of this study was to investigate the association of these SNPs in a Han Chinese population. Methods: There were 576 patients with wet AMD and 572 healthy controls collected in this study. All SNPs were genotyped by flight mass spectrum. Hardy-Weinberg equilibrium was applied to evaluate allele distributions for both AMD and control groups. The genotype and allele frequencies were evaluated using the χ2 tests. Odds ratio (OR) and 95% confidence intervals (95% CI) were calculated for the risk of genotype and allele. Results: Three of the 11 SNPs (rs11528744 in HTRA1, rs9928736 in BCRA1 and rs4381465 in B3GLCT) were found to be significantly associated with AMD in the allelic model (corrected p = 0.001, OR = 1.391, 95%CI = 1.179-1.640 for rs11528744; corrected p = 0.004, OR = 0.695, 95%CI = 0.544-0.888 for rs9928736; corrected p = 0.002, OR = 0.614, 95%CI = 0.448-0.841 for rs4381465). There were no differences for the remaining eight SNPs between AMD cases and healthy controls. Conclusion: Our results showed that HTRA1 rs11528744, BCRA1 rs9928736, and B3GLCT rs4381465 were associated with wet AMD, suggesting that HTRA1, BCRA1, and B3GLCT genes may be involved in the development of AMD.

A grooved porous hydroxyapatite scaffold induces osteogenic differentiation via regulation of PKA activity by upregulating miR-129-5p expression.

BACKGROUND AND OBJECTIVE: Hydroxyapatite scaffolds with different morphologies have been widely used in bone tissue engineering. Moreover, microRNAs (miRNAs) have been proven to be extensively involved in regulating bone regeneration. We developed grooved porous hydroxyapatite (HAG) scaffolds with good osteogenic efficiency. However, little is known about the role of miRNAs in HAG scaffold-mediated promotion of bone regeneration. The objective of this study was to reveal the mechanism from the perspective of differential miRNA expression. METHODS: Scanning electron microscopy (SEM) was used to perform the coculture of cells and scaffolds. The miRNA profiles were generated by a microarray assay. A synthetic miR-129-5p mimic and inhibitor were used for overexpression or inhibition. The expression of osteogenic marker mRNAs and proteins was detected by quantitative real-time PCR (qRT-PCR), Western blotting, and immunofluorescence. An ALP activity kit and alizarin red staining (ARS) were used to measure ALP activity and mineral deposition formation. Cell migration ability was examined by wound healing and transwell assays. Protein kinase A (PKA) activity was measured by enzyme-linked immunosorbent assay (ELISA) after miR-129-5p transfection. Target genes were identified by a dual-luciferase reporter assay. H89 preculture evaluated the cross talk between miR-129-5p and PKA activity. Heterotopic implantation models, hematoxylin-eosin (HE), immunohistochemistry staining, and micro-CT were used to evaluate miR-129-5p osteogenesis in vivo. RESULTS: miRNAs were differentially expressed during osteogenic differentiation induced by HAG in vitro and in vivo. miR-129-5p was the only highly expressed miRNA both in vitro and in vivo. miR-129-5p overexpression promoted osteoblast differentiation and cell migration, while its inhibition weakened the effect of HAG. Moreover, miR-129-5p activated PKA to regulate the phosphorylation of ß-catenin and cAMP-response element binding protein (CREB) by inhibiting cAMP-dependent protein kinase inhibitor alpha (Pkia). H89 prevented the effects of miR-129-5p on osteogenic differentiation and cell migration. HE, immunohistochemistry staining and micro-CT results showed that miR-129-5p promoted in vivo osteogenesis of the HAG scaffold. CONCLUSION: The HAG scaffold activates Pka by upregulating miR-129-5p and inhibiting Pkia, resulting in CREB-dependent transcriptional activation and accumulation of ß-catenin and promoting osteogenic marker expression.

miR-210-3p suppresses osteogenic differentiation of MC3T3-E1 by targeting brain derived neurotrophic factor (BDNF).

BACKGROUND AND OBJECTIVE: As an important mediator of intercellular interaction and formation of extracellular bone matrix, porous scaffolds are widely used for bone regeneration. Accumulating evidences demonstrate that microRNA are involved in the regulation of scaffolds-induced bone regeneration. Recently, we revealed that miR-210-3p was highly expressed during osteogenesis induced by HAG. In present study, we further explored the molecular mechanism underlying the effect of miR-210-3p on osteogenic differentiation. MATERIALS AND METHODS: In this study, miR-210-3p mimics and inhibitors were synthesized and transfected into MC3T3-E1 cells to explore their effects on osteogenic differentiation. The expression of osteogenic marker (Alp and Runx2) were detected by real-time quantitative PCR (qRT-PCR) and western blotting. After osteogenesis induction for 7 days, Alp staining were used to detected osteoblast differentiation of MC3T3-E1 cells. CCK8 and Transwell assays were performed to detected cell proliferation and migration. Then, top ranking list of target genes of miR-210-3p obtained from TargetScan and the expression of BDNF were detected by qRT-PCR and ELISA. The relationship between miR-210-3p and BDNF was verified by luciferase report assay. Furthermore, the effect of BDNF on osteoblast differentiation was verified by transfecting siRNA or adding BDNF to the culture medium. RESULTS: MiR-210-3p mimics markedly suppress osteogenic differentiation, cell migration and cell proliferation of MC3T3-E; nevertheless, silencing of miR-210-3p dramatically enhanced MC3T3-E1 osteogenesis, cell migration and proliferation. Furthermore, luciferase reporter assay verified that brain derived neurotrophic factor (BDNF) is a directly target of miR-210-3p. Moreover, BDNF siRNA significantly decreased the expression levels of ALP and cell migration. The addition of BDNF partially rescued the inhibition of osteogenesis by miR-210-3p. CONCLUSION: miR-210-3p inhibited the osteogenic differentiation via targeting BDNF. Our Results provide a promising target for regulating osteogenic differentiation.

Antibacterial and antibiofilm activities of novel antimicrobial peptide DP7 against the periodontal pathogen Porphyromonas gingivalis.

AIMS: Accumulating evidence suggests that Porphyromonas gingivalis is closely associated with the development of various chronic inflammatory diseases, particularly periodontitis. This study investigated the antibacterial activity and action mechanism of a novel antimicrobial peptide (AMP), DP7, against P. gingivalis. METHODS AND RESULTS: The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for DP7 were determined via a broth microdilution method, revealing an MIC of 8 µg ml-1 and MBC of 32 µg ml-1 . Growth inhibition and killing assays confirmed the bactericidal effect of DP7, and treatment with DP7 at MBC eliminated P. gingivalis within 8 h. DP7 had a low cytotoxic effect against human cells. Transmission electron microscopy revealed that DP7 destroyed the bacterial membrane, and confocal laser scanning microscopy revealed its inhibitory effect on P. gingivalis biofilms. Quantitative reverse transcription-polymerase chain reaction revealed DP7-mediated inhibition of several virulence factor genes, partially explaining its antibacterial mechanism. CONCLUSIONS: DP7, a novel AMP with low mammalian cytotoxicity, inhibits both planktonic and biofilm forms of P. gingivalis by destroying the bacterial membrane and reducing virulence factor gene expression. SIGNIFICANCE AND IMPACT OF THE STUDY: DP7 has potential clinical application in the prevention and treatment of P. gingivalis-associated diseases.

Iron ion-coordinated carrier-free supramolecular co-nanoassemblies of dual DNA topoisomerase-targeting inhibitors for tumor suppression.

Overexpressed DNA topoisomerase II alpha (TOP-2A) is closely related to the invasion and metastasis of malignant breast tumors. Mitoxantrone (MTX) has been identified as a TOP-2A inhibitor with significant inhibitory activity against breast tumors. The tumor-homing ability of MTX has been further enhanced by using nanodrug delivery systems (nano-DDSs), reducing off-target side effects. However, conventional MTX nano-DDSs are still limited by low drug-loading capacity and material carrier-related toxicity. In this study, we developed metal iron-coordinated carrier-free supramolecular co-nanoassemblies of dual DNA topoisomerase-targeting inhibitors with high drug loading for superimposed DNA damage-augmented tumor regression. By introducing iron ions (Ⅲ) and another TOP-2A inhibitor quercetin (QU) onto the building blocks, Fe3+-mediated QU-MTX co-nanoassemblies are fabricated (QU-MTX-Fe) via intermolecular coordination interactions. The PEGylated co-nanoassemblies (P-QU-MTX-Fe) exhibit distinct advantages over QU/MTX solution (Sol) alone or MTX-QU mixture Sol in terms of therapeutic efficacy and systemic toxicity. Meanwhile, P-QU-MTX-Fe could efficiently suppress primary and distal breast tumor relapse by activating the CD 8+-mediated antitumor immune response. Overall, such iron-coordinated nanomedicines provide insights into the rational design of drug-likeness compounds with undesirable therapeutic performance for cancer therapy. STATEMENT OF SIGNIFICANCE: Aimed at the key target TOP-2A in the malignant breast tumor, the metal coordination-mediated supramolecular co-assemble strategy of one-target dual inhibitors was firstly proposed for superimposed DNA damage for cancer therapy. Multiple interactions involving π-π stacking interactions, hydrogen bonds and coordination forces maintained the stability of co-nanoassemblies. Meanwhile, this co-nanoassemblies not only had potentials to increase therapeutic efficacy and decrease systemic toxicity, but also activated the CD 8+-mediated antitumor immune response against distal breast tumor relapse. Such a facile and safe nanoplatform is expected to provide an important prospective for promoting the clinical transformation of drug-likeness compounds in the suppression of difficult-to-treat breast tumor.

Differential Expression Profiling of microRNAs in Human Placenta-Derived Mesenchymal Stem Cells Cocultured with Grooved Porous Hydroxyapatite Scaffolds.

Scaffold materials used for bone defect repair are often limited by osteogenic efficacy. Moreover, microRNAs (miRNAs) are involved in regulating the expression of osteogenic-related genes. In previous studies, we verified the enhancement of osteogenesis using a grooved porous hydroxyapatite scaffold (HAG). In the present study, we analyzed the contribution of HAG to the osteogenic differentiation of human placenta-derived mesenchymal stem cells (hPMSCs) from the perspective of miRNA differential expression. Furthermore, results showed that miRNAs were differentially expressed in the osteogenic differentiation of hPMSCs cocultured with HAG. In detail, 16 miRNAs were significantly upregulated and 29 miRNAs were downregulated with HAG. In addition, bioinformatics analyses showed that the differentially expressed miRNAs were enriched in a variety of biological processes, including signal transduction, cell metabolism, cell junctions, cell development and differentiation, and that they were associated with osteogenic differentiation through axon guidance, mitogen-activated protein kinase, and the transforming growth factor beta signaling pathway. Furthermore, multiple potential target genes of these miRNAs were closely related to osteogenic differentiation. Importantly, overexpression of miR-146a-5p (an upregulated miRNA) promoted the osteogenic differentiation of hPMSCs, and miR-145-5p overexpression (a downregulated miRNA) inhibited the osteogenic differentiation of hPMSCs.

A transcriptome analysis for 24-hour continuous sampled uterus reveals circadian regulation of the key pathways involved in eggshell formation of chicken.

Circadian timing system controlled the rhythmic events, for example, ovulation and oviposition in chickens. However, how biological clock mediates eggshell formation remains obscure. Here, A 24-h mRNA transcriptome analysis was carried out in the uterus of 18 chickens with similar oviposition time points to identify the rhythmic genes and to reveal critical genes and biological pathways involved in the eggshell biomineralization. JTK_CYCLE analysis and real-time PCR revealed a total of 1,793 genes from the sequencing database with 23,513 genes (FPKM>1) were rhythmic genes regulating the rhythmic system and the expression of typical clock genes Per2, Cry1, Bmal1, Clock, Per3, and Rev-erbß were rhythmically expressed, which suggested that endogenous clock in uterus might control the eggshell mineralization. Time of peak expression of the rhythmic genes was analyzed based on their acrophase. The main phases clustered at the periods from Zeitgeber time 0 (ZT0) to ZT4 (6:00-10:00) and from ZT10 to ZT14 (16:00-20:00). The rhythmic genes were annotated to the following Gene Ontology terms rhythmic process, lyase, ATP binding, cell membrane component. KEGG pathway enrichment analysis revealed the top 15 rhythmic genes were involved in vital biological pathways, including syndecan (1, 2, 3)-mediated signaling, post-translational regulation of adheres junction stability and disassembly, FoxO family signaling, TGF-ß receptor and transport of small molecular pathways. 166 of total 1,235 genes (13.4%) were defined as rhythmic transfer factors (TFs) and they were investigated expression time distribution of cis-elements of circadian clock system D-box, E-box, B-site, and Y-Box within 24 h. Results indicated that rhythmic TFs at each phase are potential drivers of their circadian transcription activities. Compared with the control, the expression abundances of ion transport elements SCNN1G, CA2, SPP1, and ATP1B1 were significantly decreased after the interference of Bmal1 gene in synchronized uterine tubular gland cells. Clock genes changed their expression along with the eggshell formation, indicating that there is circadian clock in the uterus of chicken and it regulates the expression of eggshell formation genes.

Development and validation of a prognostic nomogram for colorectal cancer after surgery.

BACKGROUND: A nomogram is a diagram that aggregates various predictive factors through multivariate regression analysis, which can be used to predict patient outcomes intuitively. Lymph node (LN) metastasis and tumor deposit (TD) conditions are two critical factors that affect the prognosis of patients with colorectal cancer (CRC) after surgery. At present, few effective tools have been established to predict the overall survival (OS) of CRC patients after surgery. AIM: To screen out suitable risk factors and to develop a nomogram that predicts the postoperative OS of CRC patients. METHODS: Data from a total of 3139 patients diagnosed with CRC who underwent surgical removal of tumors and LN resection from 2010 to 2015 were collected from the Surveillance, Epidemiology, and End Results program. The data were divided into a training set (n = 2092) and a validation set (n = 1047) at random. The Harrell concordance index (C-index), Akaike information criterion (AIC), and area under the curve (AUC) were used to assess the predictive performance of the N stage from the American Joint Committee Cancer tumor-node-metastasis classification, LN ratio (LNR), and log odds of positive lymph nodes (LODDS). Univariate and multivariate analyses were utilized to screen out the risk factors significantly correlating with OS. The construction of the nomogram was based on Cox regression analysis. The C-index, receiver operating characteristic (ROC) curve, and calibration curve were employed to evaluate the discrimination and prediction abilities of the model. The likelihood ratio test was used to compare the sensitivity and specificity of the final model to the model with the N stage alone to evaluate LN metastasis. RESULTS: The predictive efficacy of the LODDS was better than that of the LNR based on the C-index, AIC values, and AUC values of the ROC curve. Seven independent predictive factors, namely, race, age at diagnosis, T stage, M stage, LODDS, TD condition, and serum carcinoembryonic antigen level, were included in the nomogram. The C-index of the nomogram for OS prediction was 0.8002 (95%CI: 0.7839-0.8165) in the training set and 0.7864 (95%CI: 0.7604-0.8124) in the validation set. The AUC values of the ROC curve predicting the 1-, 3-, and 5-year OS were 0.846, 0.841, and 0.825, respectively, in the training set and 0.823, 0.817, and 0.835, respectively, in the validation test. Great consistency between the predicted and actual observed OS for the 1-, 3-, and 5-year OS in the training set and validation set was shown in the calibration curves. The final nomogram showed a better sensitivity and specificity than the nomogram with N stage alone for evaluating LN metastasis in both the training set (-4668.0 vs -4688.3, P < 0.001) and the validation set (-1919.5 vs -1919.8, P < 0.001) through the likelihood ratio test. CONCLUSION: The nomogram incorporating LODDS, TD, and other risk factors showed great predictive accuracy and better sensitivity and specificity and represents a potential tool for therapeutic decision-making.

[Technical Realization of Integrating Bone Age Artificial Intelligence Assessment System with Hospital RIS-PACS Network].

OBJECTIVE: To explore the integration method and technical realization of artificial intelligence bone age assessment system with the hospital RIS-PACS network and workflow. METHODS: Two sets of artificial intelligence based on bone age assessment systems (CHBoneAI 1.0/2.0) were developed. The intelligent system was further integrated with RIS-PACS based on the http protocol in Python flask web framework. RESULTS: The two sets of systems were successfully integrated into the local network and RIS-PACS in hospital. The deployment has been smoothly running for nearly 3 years. Within the current network setting, it takes less than 3 s to complete bone age assessment for a single patient. CONCLUSIONS: The artificial intelligence based bone age assessment system has been deployed in clinical RIS-PACS platform and the "running in parallel", which is marking a success of Stage-I and paving the way to Stage-II where the intelligent systems can evolve to become more powerful in particular of the system self-evolution and the "running alternatively".

Structure activity relationships of chrysoeriol and analogs as dual c­Met and VEGFR2 tyrosine kinase inhibitors.

Vascular endothelial growth factor receptor 2 (VEGFR2) and c­Met are tyrosine kinases, which are involved in the tumorigenesis of various types of cancer. Previous studies have demonstrated that the elevated activation of c­Met is associated with the drug resistance of VEGFR2 inhibitors. Therefore, dual c­Met and VEGFR2 kinase inhibitors are expected to overcome VEGFR2 inhibitor resistance and subsequently lead to a superior therapeutic outcome to regular VEGFR2 inhibitors. In the present study, it was found that chrysoeriol, which can be extracted from several natural plants, was a potential dual c­Met and VEGFR2 kinase inhibitor. The results of docking experiments revealed that chrysoeriol was able to efficiently bind in the active site cavity of c­Met and VEGFR2. The results of enzymatic assays showed relatively high binding affinities of chrysoeriol to c­Met (Kd=12 µM) and VEGFR2 (Kd=11 µM). The structure activity relationships (SARs) of chrysoeriol and its analogs were investigated using pharmacological and molecular docking experiments. To the best of our best knowledge, the present study is the first to report a natural product with both c­Met and VEGFR2 inhibitory profiles, and provides insights into future dual c­Met and VEGFR2 kinase inhibitor development.

Rhythmic expression of circadian clock genes in the preovulatory ovarian follicles of the laying hen.

The circadian clock is reported to play a role in the ovaries in a variety of vertebrate species, including the domestic hen. However, the ovary is an organ that changes daily, and the laying hen maintains a strict follicular hierarchy. The aim of this study was to examine the spatial-temporal expression of several known canonical clock genes in the granulosa and theca layers of six hierarchy follicles. We demonstrated that the granulosa cells (GCs) of the F1-F3 follicles harbored intrinsic oscillatory mechanisms in vivo. In addition, cultured granulosa cells (GCs) from F1 follicles exposed to luteinizing hormone (LH) synchronization displayed Per2 mRNA oscillations, whereas, the less mature GCs (F5 plus F6) displayed no circadian change in Per2 mRNA levels. Cultures containing follicle-stimulating hormone (FSH) combined with LH expressed levels of Per2 mRNA that were 2.5-fold higher than those in cultures with LH or FSH alone. These results show that there is spatial specificity in the localization of clock cells in hen preovulatory follicles. In addition, our results support the hypothesis that gonadotropins provide a cue for the development of the functional cellular clock in immature GCs.

Genetic Variation of Nine Chicken Breeds Collected from Different Altitudes Revealed by Microsatellites.

Genetic polymorphisms of 19 microsatellites were investigated in nine local chicken breeds collected from low, middle and high altitudes areas in China (total number was 256) and their population genetic diversity and population structure were analyzed. All breeds were assigned into three groups, including the high (Tibetan chicken (T) and Grey chicken (G), their altitudes were above 1000 m); middle (Chengkou mountainous chicken (CK), Jiuyuan chicken (JY) and Pengxian yellow chicken (PY), their altitudes were between 500 and 1000 m), and low groups (Da ninghe chicken (DH), Tassel first chicken (TF), Gushi chicken (GS) and Wenchang chicken (WC), their altitudes were below 500 m). We found 780 genotypes and 324 alleles via the 19 microsatellites primers, and the results showed that the mean number of alleles (Na ) was 17.05; the average polymorphism information content (PIC) was 0.767; the mean expected heterozygosity (He) was 0.662; as for observed heterozygosity (Ho ), it was 0.647. The AMOVA results indicated the genetic variation mainly existed within individuals among populations (80%). There was no genetic variation among the three altitude groups (0%). The mean inbreeding coefficient among individuals within population (FIS ) was 0.031 and the mean gene flow (Nm ) was 1.790. The mean inbreeding coefficient among populations within a group (FST ) was 0.157. All loci deviated Hardy-Weinberg equilibrium. The genetic distance ranged from 0.090 to 0.704. Generally, genetic variations were mainly made up of the variations among populations and within individuals. There were rich gene diversities in the populations for the detected loci. Meanwhile, frequent genes exchange existed among the populations. This can lead to extinction of the peripheral species, such as the Tibetan chicken breed.

[Changes in MLS-BAEP in newborn piglets with hypoxic-ischemic brain damage during selective moderate head cooling therapy].

OBJECTIVE: To study the effect of selective moderate head cooling therapy on maximum length sequences brainstem auditory evoked potential (MLS-BAEP) in newborn piglets with hypoxic-ischemic brain damage. METHODS: Sixteen newborn piglets aged 5-7 day old were randomly divided into three groups: normothermic control (n=4), HI (n=6) and mild hypothermia-treated (n=6). HI was induced through temporary occlusion of both carotid arteries, followed by mechanical ventilation with low concentration of oxygen (FiO2=0.06) for 30 minutes. Mild hypothermia was induced by equipment via circulating water. MLS-BAER was recorded before HI and at 12 hours, 24 hours, 36 hours, 48 hours, 60 hours, 72 hours, 4 days, 7 days, 10 days, 13 days and 15 days after HI. RESULTS: Compared with the normothermic control group, all latencies and intervals tended to increase significantly at 72 hours in the HI group and reached peak values on day 7. From day 10, all latencies and intervals tended to decrease, but apart from wave I latency, still differed significantly from those of the normothermic control group. MLS-BAER variables did not reach normal values until day 15. Ⅲ latency, Ⅰ-Ⅲ interval and Ⅰ-Ⅴ interval were significantly reduced in the hypothermia-treated group between 60 and 7 days after HI compared with the HI group (P<0.05). V latency and Ⅲ-Ⅴ interval in the hypothermia-treated group were also reduced compared with the HI group between 72 hours and 7 days after HI (P<0.05). CONCLUSIONS: Both peripheral and central auditory systems are disturbed by HI, which shows as a significant increase in MLS-BAER variables (all latencies and intervals) in newborn piglets. Involvement in central brainstem auditory system reaches a peak on day 7 after injury. MLS-BAER variables still cannot reach to normal values until day 15. Selective moderate head cooling therapy can significantly reduce brainstem damage induced by HI.

Changes in MLS-BAEP in newborn piglets with hypoxic-ischemic brain damage during selective moderate head cooling therapy / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the effect of selective moderate head cooling therapy on maximum length sequences brainstem auditory evoked potential (MLS-BAEP) in newborn piglets with hypoxic-ischemic brain damage.</p><p><b>METHODS</b>Sixteen newborn piglets aged 5-7 day old were randomly divided into three groups: normothermic control (n=4), HI (n=6) and mild hypothermia-treated (n=6). HI was induced through temporary occlusion of both carotid arteries, followed by mechanical ventilation with low concentration of oxygen (FiO2=0.06) for 30 minutes. Mild hypothermia was induced by equipment via circulating water. MLS-BAER was recorded before HI and at 12 hours, 24 hours, 36 hours, 48 hours, 60 hours, 72 hours, 4 days, 7 days, 10 days, 13 days and 15 days after HI.</p><p><b>RESULTS</b>Compared with the normothermic control group, all latencies and intervals tended to increase significantly at 72 hours in the HI group and reached peak values on day 7. From day 10, all latencies and intervals tended to decrease, but apart from wave I latency, still differed significantly from those of the normothermic control group. MLS-BAER variables did not reach normal values until day 15. Ⅲ latency, Ⅰ-Ⅲ interval and Ⅰ-Ⅴ interval were significantly reduced in the hypothermia-treated group between 60 and 7 days after HI compared with the HI group (P<0.05). V latency and Ⅲ-Ⅴ interval in the hypothermia-treated group were also reduced compared with the HI group between 72 hours and 7 days after HI (P<0.05).</p><p><b>CONCLUSIONS</b>Both peripheral and central auditory systems are disturbed by HI, which shows as a significant increase in MLS-BAER variables (all latencies and intervals) in newborn piglets. Involvement in central brainstem auditory system reaches a peak on day 7 after injury. MLS-BAER variables still cannot reach to normal values until day 15. Selective moderate head cooling therapy can significantly reduce brainstem damage induced by HI.</p>