Assortative mating on blood type: Evidence from one million Chinese pregnancies.

Blood type is one of the most fundamental phenotypes in biological, medical, and psychological studies. Using a unique dataset of one million Chinese pregnancies, we find strong evidence from a group of statistical tests for assortative mating on blood type. After controlling for anthropometric and socioeconomic confounders, assortative mating remains robust.

Analysis of complex chromosomal rearrangement involving chromosome 6 via the integration of optical genomic mapping and molecular cytogenetic methodologies.

Complex chromosomal rearrangements (CCRs) can result in spontaneous abortions, infertility, and malformations in newborns. In this study, we explored a familial CCR involving chromosome 6 by combining optical genomic mapping (OGM) and molecular cytogenetic methodologies. Within this family, the father and the paternal grandfather were both asymptomatic carriers of an identical balanced CCR, while the two offspring with an unbalanced paternal-origin CCR and two microdeletions presented with clinical manifestation. The first affected child, a 5-year-old boy, exhibited neurodevelopmental delay, while the second, a fetus, presented with hydrops fetalis. SNP-genotype analysis revealed a recombination event during gamete formation in the father that may have contributed to the deletion in his offspring. Meanwhile, the couple's haplotypes will facilitate the selection of normal gametes in the setting of assisted reproduction. Our study demonstrated the potential of OGM in identifying CCRs and its ability to work with current methodologies to refine precise breakpoints and construct accurate haplotypes for couples with a CCR.

Patients with Crohn's Disease Undergoing Abdominal Surgery: Clinical and Prognostic Evaluation Based on a Single-Center Cohort in China.

BACKGROUND: The incidence and prevalence of Crohn's disease (CD) are increasing in China, but there are few reports on the characteristics of patients requiring abdominal surgery. This study aimed to evaluate the clinical characteristics of these patients and the potential risk factors for postoperative complications and surgical recurrence. METHODS: In this observational, retrospective single-center cohort analysis, patients with CD who had undergone at least one abdominal surgery at our center from 2007 to 2020 were included. Data were collected from a prospectively maintained database. Clinical factors were assessed by logistic regression models, Kaplan-Meier methods, and Cox proportional hazards regression models. The predictive accuracy of the nomogram was determined by a concordance index (C-index) and calibration curve and was validated using bootstrap resampling. RESULTS: In the 1639 patients, clinical characteristics were evaluated. In a multivariable logistic regression model, penetrating behavior (P = 0.002), emergency surgery (P = 0.010), and smoking status (P = 0.015) were significantly associated with an increased risk of postoperative septic complications. In contrast, staged surgery (P = 0.009) was inversely associated with postoperative complications. Upper gastrointestinal disease (P = 0.042), penetrating behavior (P = 0.027), emergency at initial surgery (P < 0.001) were significantly associated with an increased risk of surgical recurrence after the index surgery in our Cox regression model, whereas staged surgery (P = 0.036) was significantly associated with a decreased risk. The C-index of the nomogram for predicting recurrence was 0.744 (P = 0.015), and calibration curves showed good agreement between predictions of 3, 5, and 10 years of recurrence and actual observations. CONCLUSIONS: There are several disease- and surgery-associated risk factors of postoperative adverse outcomes in patients with CD undergoing abdominal surgery. This is important in optimizing the management of CD which has evolved into a global disease with rising prevalence in newly industrialized countries including China.

Hydrophilic interaction and reversed-phase ultra-performance liquid chromatography TOF-MS for metabolomic analysis of Veratrum nigrum-induced cardiotoxicity.

The acute cardiotoxicity induced by Veratrum nigrum (VN) is explored by analyzing heart tissue metabolic profiles in mouse models and applying reversed-phase liquid chromatography mass spectrometry and hydrophilic interaction liquid chromatography mass spectrometry that are based on ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry. An animal model of acute heart injury was established in mice via intra-gastric administration of VN. Then, electrocardiogram and echocardiograph monitoring of cardiac function and pathological examination were performed on mice in both the control and VN groups, and it was verified that acute heart injury was caused. Meanwhile, comparing the results of the control and VN groups, we detected 36 differential endogenous metabolites of heart tissue, including taurine, riboflavin, purine and lipids, which are related to many possible pathways such as purine metabolism, taurine and hypotaurine metabolism and energy metabolism. Our study provides a scientific approach for evaluating and revealing the mechanisms of VN-induced cardiotoxicity via the metabolomic strategy.

Particulate Matter (PM) and Parent, Nitrated and Oxygenated Polycyclic Aromatic Hydrocarbon (PAH) Emissions of Emulsified Heavy Fuel Oil in Marine Low-Speed Main Engine.

To understand the influences of emulsified fuel on ship exhaust emissions more comprehensively, the emissions of particulate matter (PM), nitrated, oxygenated and parent polycyclic aromatic hydrocarbons (PAHs) were studied on a ship main engine burning emulsified heavy fuel oil (EHFO) and heavy fuel oil (HFO) as a reference. The results demonstrate that EHFO (emulsified heavy fuel oil) exhibits notable abilities to significantly reduce emissions of particulate matter (PM) and low molecular weight PAHs (polycyclic aromatic hydrocarbons) in the gas phase, particularly showcasing maximum reductions of 13.99% and 40.5%, respectively. Nevertheless, burning EHFO could increase the emission of high molecular weight PAHs in fine particles and pose a consequent higher carcinogenic risk for individual particles. The total average (gaseous plus particulate) ΣBEQ of EHFO exhausts (41.5 µg/m3) was generally higher than that of HFO exhausts (18.7 µg/m3). Additionally, the combustion of EHFO (extra-heavy fuel oil) can significantly alter the emission quantity, composition, and particle-size distribution of PAH derivatives. These changes may be linked to molecular structures, such as zigzag configurations in C=O bonds. Our findings may favor the comprehensive environmental assessments on the onboard application of EHFO.

Amorphous Gallium Oxide-Based Crosstalk-Suppressing Solar-Blind Imaging Array Prepared by One-Step Method.

The solar-blind ultraviolet band presents a unique opportunity for low-background-noise detection due to limited atmospheric light transmission. Especially, with the ability to obtain size, shape and position information on the objects, the solar-blind image sensors are receiving increasing attention. However, because the inhibition of the crosstalk in crossbar arrays induces the complexity of the preparation process, rarely are applicable solar-blind UV imaging arrays reported. This work prepared an amorphous gallium oxide (a-Ga2O3)-based diode with a remarkable rectifier ratio of up to 106. Then an imaging array was prepared by one-step method in that the diodes working as the detection elements and the switching elements inhibiting crosstalk were simultaneously deposited. Moreover, a 2 × 2 crossbar array clearly demonstrates the inhibition of the crosstalk. This work presents a simple and cost-effective method for preparing applicable solar-blind imaging arrays that inhibits crosstalk, promoting the practical application of the Ga2O3-based solar-blind UV detectors.

Tensile Stress-Activated and Exosome-Transferred YAP/TAZ-Notch Circuit Specifies Type H Endothelial Cell for Segmental Bone Regeneration.

The Ilizarov technique has been continuously innovated to utilize tensile stress (TS) for inducing a bone development-like regenerative process, aiming to achieve skeletal elongation and reconstruction. However, it remains uncertain whether this distraction osteogenesis (DO) process induced by TS involves the pivotal coupling of angiogenesis and osteogenesis mediated by type H endothelial cells (THECs). In this study, it is demonstrated that the Ilizarov technique induces the formation of a metaphysis-like architecture composed of THECs, leading to segmental bone regeneration during the DO process. Mechanistically, cell-matrix interactions-mediated activation of yes-associated protein (YAP)/transcriptional co-activator with PDZ-binding motif (TAZ) transcriptionally upregulates the expression of Notch1 and Delta-like ligand 4, which act as direct positive regulators of THECs phenotype, in bone marrow endothelial cells (BMECs) upon TS stimulation. Simultaneously, the Notch intracellular domain enhances YAP/TAZ activity by transcriptionally upregulating YAP expression and stabilizing TAZ protein, thus establishing the YAP/TAZ-Notch circuit. Additionally, TS-stimulated BMECs secrete exosomes enriched with vital molecules in this positive feedback pathway, which can be utilized to promote segmental bone defect healing, mimicking the therapeutic effects of Ilizarov technique. The findings advance the understanding of TS-induced segmental bone regeneration and establish the foundation for innovative biological therapeutic strategies aimed at activating THECs.

The Application of Optical Genome Mapping (OGM) in Severe Short Stature Caused by Duplication of 15q14q21.3.

(1) Background: Optical genome mapping (OGM) is a novel approach to identifying genomic structural variations with high accuracy and resolution. We report a proband with severe short stature caused by 46, XY, der (16) ins (16;15) (q23; q21.3q14) that was detected by OGM combined with other tests and review the clinical features of patients with duplication within 15q14q21.3; (2) Methods: OGM, whole exon sequencing (WES), copy number variation sequencing (CNV-seq), and karyotyping were used; (3) Results: The proband was a 10.7-year-old boy with a complaint of severe short stature (-3.41SDS) and abnormal gait. He had growth hormone deficiency, lumbar lordosis, and epiphyseal dysplasia of both femurs. WES and CNV-seq showed a 17.27 Mb duplication of chromosome 15, and there was an insertion in chromosome 16 found by karyotyping. Furthermore, OGM revealed that duplication of 15q14q21.3 was inversely inserted into 16q23.1, resulting in two fusion genes. A total of fourteen patients carried the duplication of 15q14q21.3, with thirteen previously reported and one from our center, 42.9% of which were de novo. In addition, neurologic symptoms (71.4%,10/14) were the most common phenotypes; (4) Conclusions: OGM combined with other genetic methods can reveal the genetic etiology of patients with the clinical syndrome, presenting great potential for use in properly diagnosing in the genetic cause of the clinical syndrome.

Evaluation and Analysis of Absence of Homozygosity (AOH) Using Chromosome Analysis by Medium Coverage Whole Genome Sequencing (CMA-seq) in Prenatal Diagnosis.

OBJECTIVE: Absence of homozygosity (AOH) is a genetic characteristic known to cause human diseases mainly through autosomal recessive or imprinting mechanisms. The importance and necessity of accurate AOH detection has become more clinically significant in recent years. However, it remains a challenging task for sequencing-based methods thus far. METHODS: In this study, we developed and optimized a new bioinformatic algorithm based on the assessment of minimum sequencing coverage, optimal bin size, the Z-score threshold of four types of allele count and the frequency for accurate genotyping using 28 AOH negative samples, and redefined the AOH detection cutoff value. We showed the performance of chromosome analysis by five-fold coverage whole genome sequencing (CMA-seq) for AOH identification in 27 typical prenatal/postnatal AOH positive samples, which were previously confirmed by chromosomal microarray analysis with single nucleotide polymorphism array (CMA/SNP array). RESULTS: The blinded study indicated that for all three forms of AOH, including whole genomic AOH, single chromosomal AOH and segmental AOH, and all kinds of sample types, including chorionic villus sampling, amniotic fluid, cord blood, peripheral blood and abortive tissue, CMA-seq showed equivalent detection power to that of routine CMA/SNP arrays (750K). The subtle difference between the two methods is that CMA-seq is prone to detect small inconsecutive AOHs, while CMA/SNP array reports it as a whole. CONCLUSION: Based on our newly developed bioinformatic algorithm, it is feasible to detect clinically significant AOH using CMA-seq in prenatal diagnosis.

Detection of Mosaic Absence of Heterozygosity (AOH) Using Low-Pass Whole Genome Sequencing in Prenatal Diagnosis: A Preliminary Report.

Objective: Mosaicism is a common biological phenomenon in organisms and has been reported in many types of chromosome abnormalities, including the absence of heterozygosity (AOH). Due to the detection limitations of the sequencing approach, mosaic AOH events are rarely assessed in clinical cases. Herein, we report the performance of mosaic AOH identification using a low-pass (5~8-fold) WGS method (termed 'CMA-seq', an abbreviation for 'Chromosome Analysis by Sequencing') in fetal genetic diagnosis. Methods: Thirty AOH-negative, eleven constitutional AOH, and three mosaic AOH samples were collected as training data sets to develop the algorithm and evaluate the suitable thresholds for distinguishing mosaic AOH. Twenty-four new chromosomal aberrant cases, along with sixteen constitutional AOH samples, which were previously ascertained via the SNP-array-based method, were used as a validation data set to measure the performance in terms of sensitivity and specificity of this algorithm. Results: A new statistic, 'D-value', was implemented to identify and distinguish constitutional and mosaic AOH events. The reporting thresholds for constitutional and mosaic AOH were also established. In the validation set consisting of 24 new cases, seven constitutional AOH cases and 1 mosaic AOH case were successfully identified, indicating that the results were consistent with those of the SNP-array-based method. The results of all sixteen constitutional AOH validation samples also met the threshold requirements. Conclusions: In this study, we developed a new bioinformatic algorithm to accurately distinguish mosaic AOH from constitutional AOH by low-pass WGS. However, due to the small sample size of the training data set, the algorithm proposed in this manuscript still needs further refinements.

Comparative effectiveness of biologics and targeted therapies for psoriatic arthritis.

OBJECTIVE: To quantify comparative effectiveness of interleukin (IL)-12/23 antagonist (ustekinumab), IL-17A antagonists (secukinumab and ixekizumab), PDE4 inhibitor (apremilast) and tumour necrosis factor-alpha (TNF-α) inhibitors (infliximab, etanercept, adalimumab, certolizumab pegol and golimumab) for psoriatic arthritis (PsA). METHODS: We adapted a deidentified claims-based algorithm validated for inflammatory arthritis treatments to compare treatments among a retrospective cohort of commercially insured and Medicare Advantage beneficiaries with PsA from October 2013 to April 2019 in the OptumLabs Data Warehouse. Main outcomes include (1) treatment effectiveness, based on: adherence, adding or switching biologic or PDE4, addition of new non-biologic disease-modifying antirheumatic drug, increase in biologic or PDE4 dose or frequency and glucocorticoid use and (2) percentage of each group fulfilling the effectiveness algorithm. We used Poisson regression with robust variance stratified by prior PsA biologic exposure and adjusted for potential confounders. RESULTS: Of 2730 individuals with PsA, 327 received IL-12/23, 138 IL-17A's, 624 PDE4 and 1641 TNF-α's. Effectiveness criteria were fulfilled among 63 (19.3%) IL-12/23 recipients, 40 (29.0%) IL-17A recipients, 160 (25.6%) PDE4 recipients and 530 (32.3%) TNF-α recipients. Among biologic-naïve individuals, IL-12/23 was less effective than TNF-α's with fully adjusted relative risk (aRR) compared with TNF-α's of 0.63 (95% CI 0.45 to 0.89). Among biologic-experienced individuals, PDE4 recipients were less effective than TNF-α's (aRR 0.67, 95% CI 0.46 to 0.96). CONCLUSIONS: TNF-α's appeared more effective than IL-12/23's for biologic-naïve individuals, and PDE4's for biologic-experienced individuals. These results may help inform treatment choice for individuals with PsA.

Antiapoptotic and antiautophagic effects of glial cell line-derived neurotrophic factor and hepatocyte growth factor after transient middle cerebral artery occlusion in rats.

Glial cell line-derived neurotrophic factor (GDNF) and hepatocyte growth factor (HGF) are strong neurotrophic factors, which function as antiapoptotic factors. However, the neuroprotective effect of GDNF and HGF in ameliorating ischemic brain injury via an antiautophagic effect has not been examined. Therefore, we investigated GDNF and HGF for changes of infarct size and antiapoptotic and antiautophagic effects after transient middle cerebral artery occlusion (tMCAO) in rats. For the estimation of ischemic brain injury, the infarct size was calculated at 24 hr after tMCAO by HE staining. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin in situ nick end labeling (TUNEL) was performed for evaluating the antiapoptotic effect. Western blot analysis of microtubule-associated protein 1 light chain 3 (LC3) and immunofluorescence analysis of LC3 and phosphorylated mTOR/Ser(2448) (p-mTOR) were performed for evaluating the antiautophagic effect. GDNF and HGF significantly reduced infarct size after cerebral ischemia. The amounts of LC3-I plus LC3-II (relative to beta-tubulin) were significantly increased after tMCAO, and GDNF and HGF significantly decreased them. GDNF and HGF significantly increased p-mTOR-positive cells. GDNF and HGF significantly decreased the numbers of TUNEL-, LC3-, and LC3/TUNEL double-positive cells. LC3/TUNEL double-positive cells accounted for about 34.3% of LC3 plus TUNEL-positive cells. This study suggests that the protective effects of GDNF and HGF were greatly associated with not only the antiapoptotic but also the antiautophagic effects; maybe two types of cell death can occur in the same cell at the same time, and GDNF and HGF are capable of ameliorating these two pathways.

Therapeutic strategy for ischemic stroke.

Possible strategies for treating ischemic stroke include: (1) Neuroprotection: preventing damaged neurons from undergoing apoptosis in the acute phase of cerebral ischemia; (2) Stem cell therapy: the repair of broken neuronal networks with newly born neurons in the chronic phase of cerebral ischemia. Firstly, we studied the neuroprotective effect of a calcium channel blocker, azelnidipine, or a by-product of heme degradation, biliverdin, in the ischemic brain. These results revealed both azelnidipine and biliverdin had a neuroprotective effect in the ischemic brain through their anti-oxidative property. Secondly, we investigated the role of granulocyte colony-stimulating factor (G-CSF) by administering G-CSF to rats after cerebral ischemia and found G-CSF plays a critical role in neuroprotection. Lastly, we developed a restorative stroke therapy with a bio-affinitive scaffold, which is able to provide an appropriate environment for newly born neurons. In the future, we will combine these strategies to develop more effective therapies for treatment of strokes.

Relationship of High-mobility group box 1 levels and multiple sclerosis: A systematic review and meta-analysis.

BACKGROUND: Multiple sclerosis (MS) is a chronic inflammatory demyelinating disorder of the central nervous system (CNS) affecting more than 2.5 million people worldwide. However, the exact etiology of MS remains unknown, recent research indicated that High-mobility group box 1(HMGB1) might contribute to MS pathogenesis. By evaluating HMGB1 levels of peripheral blood mononuclear cells (PBMC), serum and cerebrospinal fluid (CSF) in multiple sclerosis (MS) patients and the controls, to reveal the relationship of HMGB1 levels and MS patients. METHODS: The PubMed, EMBASE, the Cochrane library, China National Knowledge Infrastructure (CNKI) and WanFangData were searched for relevant studies. Pooled standardized mean difference (SMD) and 95% confidence interval (CI) were calculated as effect size, random-effects model was used when I2 > 50%. Subgroup analysis was conducted by subtype of MS, categories of controls, country and mean age. RESULTS: A total of 7 studies with 364 patients of MS and 222 controls were included. The results of this study showed that HMGB1 protein levels of PBMC and CSF in patients with MS were significantly higher than those of controls (SMD = 4.36, 95% CI = 3.69-5.02, and SMD = 0.85, 95% CI = 0.42-1.28, respectively), but we found no significant difference in HMGB1 mRNA level of PBMC and serum HMGB1 protein level between MS patients and controls. In the subgroup analysis, RRMS patients had a higher HMGB1 level in serum (p < 0.05) and CSF (p < 0.01) compared to healthy controls and non-inflammatory neurological disorder controls. In Asians, MS patients had a considerably higher HMGB1 level in serum (p < 0.05), PBMC (protein) (p < 0.01) and CSF (p < 0.01) compared to healthy controls and non-inflammatory neurological disorder controls. CONCLUSION: MS patients had higher HMGB1 protein levels in PBMC and CSF compared to controls. HMGB1 might be a new treatment target for MS.

Reduction of cerebral infarction in rats by biliverdin associated with amelioration of oxidative stress.

Biliverdin (BV), one of the byproducts of heme catalysis through heme oxygenase (HO) system, is a scavenger of reactive oxygen species (ROS). We hypothesized that BV treatment could protect rat brain cells from oxidative injuries via its anti-oxidant efficacies. Cerebral infarction was induced by transient middle cerebral artery occlusion (tMCAO) for 90 min, followed by reperfusion. BV or vehicle was administered intraperitoneally immediately after reperfusion. The size of the cerebral infarction 2 days after tMCAO was evaluated by 2,3,5-triphenyltetrazolium chloride (TTC) stain. Superoxide generation 4 h after tMCAO was determined by detection of oxidized hydroethidine. In addition, the oxidative impairment of neurons were immunohistochemically assessed by stain for lipid peroxidation with 4-hydroxy-2-nonenal (4-HNE) and damaged DNA with 8-hydroxy-2'-deoxyguanosine (8-OHdG). BV treatment significantly reduced infarct volume of the cerebral cortices associated with less superoxide production and decreased oxidative injuries of brain cells. The present study demonstrated that treatment with BV ameliorated the oxidative injuries on neurons and decreased brain infarct size in rat tMCAO model.

Sendai virus-mediated gene transfer of GDNF reduces AIF translocation and ameliorates ischemic cerebral injury.

The therapeutic effect of a novel RNA viral vector, Sendai virus (SeV)-mediated glial cell line-derived neurotrophic factor (GDNF) gene (SeV/GDNF), on the infarct volume, was investigated after 90 minutes of transient middle cerebral artery occlusion (tMCAO) in rats with relation to nuclear translocation of apoptosis inducing factor (AIF). The topical administration of SeV/GDNF induced high level expression of GDNF protein, which effectively reduced the infarct volume when administrated 0 and 1 hours as well after the reperfusion. Twenty-four hours after ischemia, the obvious nuclear translocation of AIF was found in neurons of peri-infarct area, which significantly reduced with administration of SeV/GDNF 0 or 1 hour after reperfusion, as well as the number of TUNEL positive cells. These results demonstrate that SeV vector-mediated gene transfer of GDNF effectively reduced ischemic infarct volume after tMCAO and extended the therapeutic time window compared with previous viral vectors, and that promoting neuronal survival of GDNF might be related to the reduction of AIF nuclear translocation, indicating the high therapeutic potency of SeV/GDNF for cerebral ischemia.

Estimated Costs of Pivotal Trials for Novel Therapeutic Agents Approved by the US Food and Drug Administration, 2015-2016.

Importance: A critical question in health care is the extent of scientific evidence that should be required to establish that a new therapeutic agent has benefits that outweigh its risks. Estimating the costs of this evidence of efficacy provides an important perspective. Objective: To estimate costs and assess scientific characteristics of pivotal efficacy trials that supported the approval of new therapeutic agents by the US Food and Drug Administration (FDA) from 2015 to 2016. Design and Setting: This study identified 59 novel therapeutic drugs using the annual summary reports from the FDA Center for Drug Evaluation and Research. ClinicalTrials.gov, FDA reviews, and peer-reviewed publications that were publicly available in 2017 were used to identify 52 characteristics of each efficacy trial. Costs were calculated with a global clinical trial cost assessment tool available to contract research organizations and pharmaceutical sponsors. Main Outcomes and Measures: Estimated mean cost and 95% CIs based on industry benchmark data from 60 countries. Measures of trials' scientific characteristics included trial design (no control group, placebo, and active drug), end point (surrogate outcome, clinical scale, and clinical outcome), patient enrollment, and treatment duration. Results: A total of 138 pivotal clinical trials provided the basis for approval of 59 new therapeutic agents by the FDA from 2015 to 2016, with a median estimated cost of $19.0 million (interquartile range, $12.2 million-$33.1 million). Estimated costs ranged from less than $5 million for trials without a control group for 3 orphan drugs with fewer than 15 patients each to $346.8 million (95% CI, $252.0 million-$441.5 million) for a noninferiority trial with end points assessing clinical benefit. Twenty-six of 138 trials (18.8%) were uncontrolled, with a mean estimated cost of $13.5 million (95% CI, $10.1 million-$16.9 million). Trials designed with placebo or active drug comparators had an estimated mean cost of $35.1 million (95% CI, $25.4 million-$44.8 million). Costs also varied by trial end point, treatment duration, patient enrollment, and therapeutic area. Conclusions and Relevance: The highest-cost trials were those in which the new agent had to be proved to be noninferior with clinical benefit end points compared with an agent already available or those that required larger patient populations to achieve statistical power to document smaller treatment effects or accrue infrequently occurring end points.

Expression of netrin-1 and its receptors DCC and neogenin in rat brain after ischemia.

It is very important to investigate the mechanism of axonal growth in the ischemic brain in order to consider a novel mean of therapy for stroke. Netrins are chemotropic factors for axon with chemoattractant or chemorepellant guidance activities, and deleted in colorectal cancer (DCC) and neogenin are receptors for netrins. In this study, we examined expressions of netrin-1, DCC, and neogenin in the brain after 90 min of transient middle cerebral artery occlusion (tMCAO). Netrin-1 was expressed in neurons at the peri-ischemic area with a peak at 14 days. DCC was expressed both in neurons and astrocytic feet with a peak at 14 days, though neogenin was expressed in endothelial cells at MCA territory with a peak at the same time point. These results suggest that netrin-1 is involved in the promotion of axonal growth. The expression of netrin-1 and DCC was overlapped both in the spatial and temporal patterns, indicating that DCC plays a role in netrin-1's axonal growth promoting effects. The location of neogenin positive cells differed from that of netrin-1 positive cells, thus its angiogenic activity may not have relevance with netrin-1.

Vascular endothelial growth factor promotes brain tissue regeneration with a novel biomaterial polydimethylsiloxane-tetraethoxysilane.

In the brain after infarction or trauma, the tissue eventually becomes pannecrotic and forms a cavity. In such situations, a scaffold is necessary for the implanted or migrated cells to produce new tissue. In this present study, therefore, we attempted to restore brain tissue using a novel biomaterial, polydimethylsiloxane-tetraethoxysilane (PDMS-TEOS) hybrid with or without vascular endothelial growth factor (VEGF), which is crucial for new vessel formation. When PDMS-TEOS scaffold was implanted into the artificial brain defect, it remained at the implanted site and kept the integrity of the brain shape. At 30 days after the implantation, the marginal territory of PDMS-TEOS scaffold became occupied by newly formed tissue. Immunohistochemical analysis revealed that the new tissue was constituted by astrocytes and endothelial cells. Addition of VEGF increased the newly produced tissue volume, and the immunohistochemical analysis showed that the numbers of astrocytes and endothelial cells were increased. Double staining with proliferation maker Ki67 demonstrated that VEGF significantly increased newly formed astrocytes and endothelial cells, indicating that addition of VEGF accelerated tissue restoration and angiogenesis. These findings show that implantation of PDMS-TEOS scaffold with VEGF might be effective for treating old brain infarction or trauma.

Potentiation of neurogenesis and angiogenesis by G-CSF after focal cerebral ischemia in rats.

Recently, granulocyte colony-stimulating factor (G-CSF) is expected to demonstrate beneficial effects on cerebral ischemia. Here, we showed the potential benefit of G-CSF administration after transient middle cerebral artery occlusion (tMCAO). Adult male Wistar rats received vehicle or G-CSF (50 microg/kg) subcutaneously after reperfusion, and were treated with 5-bromodeoxyuridine (BrdU, 50 mg/kg) once daily by the intraperitoneal route for 3 days after tMCAO. Nissl-stained sections at 7 days after tMCAO showed significant reduction of the infarction area (31%, P<0.01). At 7 days after tMCAO, BrdU plus NeuN double-positive cells increased by 43.3% in the G-CSF-treated group (P<0.05), and BrdU-positive endothelial cells were increased 2.29 times in the G-CSF-treated group, to a level as high as that in the vehicle-treated group (P<0.01), in the periischemic area. Our results indicate that G-CSF caused potentiation of neuroprotection and neurogenesis and is expected to have practical therapeutic potential in treating individuals after ischemic brain injury.