Direct Electroplating Ruthenium Precursor on the Surface Oxidized Nickel Foam for Efficient and Stable Bifunctional Alkaline Water Electrolysis.

Water electrolysis to produce hydrogen (H2) using renewable energy is one of the most promising candidates for realizing carbon neutrality, but its reaction kinetics is hindered by sluggish anodic oxygen evolution reaction (OER). Ruthenium (Ru) in its high-valence state (oxide) provides one of the most active OER sites and is less costly, but thermodynamically unstable. The strong interaction between Ru nanoparticles (NPs) and nickel hydroxide (Ni(OH)2) is leveraged to directly form Ru-Ni(OH)2 on the surface of a porous nickel foam (NF) electrode via spontaneous galvanic replacement reaction. The formation of Ru─O─Ni bonds at the interface of the Ru NPs and Ni(OH)2 (Ru-Ni(OH)2) on the surface oxidized NF significantly enhance stability of the Ru-Ni(OH)2/NF electrode. In addition to OER, the catalyst is active enough for the hydrogen evolution reaction (HER). As a result, it is able to deliver overpotentials of 228 and 15 mV to reach 10 mA cm-2 for OER and HER, respectively. An industry-scale evaluation using Ru-Ni(OH)2/NF as both OER and HER electrodes demonstrates a high current density of 1500 mA cm-2 (OER: 410 mV; HER: 240 mV), surpassing commercial RuO2 (OER: 600 mV) and Pt/C based performance (HER: 265 mV).

The extent of harmful volatile organic compounds released when smoking after breaking the flavor capsules of heat-not-burn (HNB) cigarette products.

A number of flavored capsule heat-not-burn (FC-HNB) tobacco products such as IQOS, Lil, and Glo have been introduced as a new generation of cigarettes. As they can release various types of volatile organic compounds (VOCs), it is important to assess the harmfulness associated with their use. Thus, the composition of VOCs in HNB cigarette vapor was evaluated to investigate the interactive roles of key variables controlling the relationships between VOC composition and capsule breaking, particularly the compositional changes induced by capsule breaking and release of flavor from FC-HNB cigarettes relative to regular products. As the capsules of FC-HNB cigarettes were broken, the total VOC concentrations increased by as high as eight times from 60.3 ± 0.48 to 488 ± 21.8 µg cig-1. The key VOC components released after breaking the flavored capsules were identified as ethyl butyrate (157 ± 13.6 µg cig-1; Lil), isoamyl acetate (76.9 ± 1.98 µg cig-1; Lil), and limonene (52.3 ± 3.29 µg cig-1; Glo). If the primary health risks of FC-HNB cigarette vapor are assessed using National Institute for Occupational Safety & Health (NIOSH) guidelines, 2,3-butanedinone exceeds the maximum daily intake limit (i.e., 0.05 mg day-1). Our study is expected to offer valuable insights into the harmful effects of direct and indirect exposure to various VOCs in FC-HNB products.

Deep learning-based fully automatic segmentation of the maxillary sinus on cone-beam computed tomographic images.

The detection of maxillary sinus wall is important in dental fields such as implant surgery, tooth extraction, and odontogenic disease diagnosis. The accurate segmentation of the maxillary sinus is required as a cornerstone for diagnosis and treatment planning. This study proposes a deep learning-based method for fully automatic segmentation of the maxillary sinus, including clear or hazy states, on cone-beam computed tomographic (CBCT) images. A model for segmentation of the maxillary sinuses was developed using U-Net, a convolutional neural network, and a total of 19,350 CBCT images were used from 90 maxillary sinuses (34 clear sinuses, 56 hazy sinuses). Post-processing to eliminate prediction errors of the U-Net segmentation results increased the accuracy. The average prediction results of U-Net were a dice similarity coefficient (DSC) of 0.9090 ± 0.1921 and a Hausdorff distance (HD) of 2.7013 ± 4.6154. After post-processing, the average results improved to a DSC of 0.9099 ± 0.1914 and an HD of 2.1470 ± 2.2790. The proposed deep learning model with post-processing showed good performance for clear and hazy maxillary sinus segmentation. This model has the potential to help dental clinicians with maxillary sinus segmentation, yielding equivalent accuracy in a variety of cases.

Quantitative analysis of the mouth opening movement of temporomandibular joint disorder patients according to disc position using computer vision: a pilot study.

Background: Temporomandibular joint disorder (TMD), which is a broad category encompassing disc displacement, is a common condition with an increasing prevalence. This study aimed to develop an automated movement tracing algorithm for mouth opening and closing videos, and to quantitatively analyze the relationship between the results obtained using this developed system and disc position on magnetic resonance imaging (MRI). Methods: Mouth opening and closing videos were obtained with a digital camera from 91 subjects, who underwent MRI. Before video acquisition, an 8.0-mm-diameter circular sticker was attached to the center of the subject's upper and lower lips. The automated mouth opening tracing system based on computer vision was developed in two parts: (I) automated landmark detection of the upper and lower lips in acquired videos, and (II) graphical presentation of the tracing results for detected landmarks and an automatically calculated graph height (mouth opening length) and width (sideways values). The graph paths were divided into three types: straight, sideways-skewed, and limited-straight line graphs. All traced results were evaluated according to disc position groups determined using MRI. Graph height and width were compared between groups using analysis of variance (SPSS version 25.0; IBM Corp., Armonk, NY, USA). Results: Subjects with a normal disc position predominantly (85.72%) showed straight line graphs. The other two types (sideways-skewed or limited-straight line graphs) were found in 85.0% and 89.47% in the anterior disc displacement with reduction group and in the anterior disc displacement without reduction group, respectively, reflecting a statistically significant correlation (χ2=38.113, P<0.001). A statistically significant difference in graph height was found between the normal group and the anterior disc displacement without reduction group, 44.90±9.61 and 35.78±10.24 mm, respectively (P<0.05). Conclusions: The developed mouth opening tracing system was reliable. It presented objective and quantitative information about different trajectories from those associated with a normal disc position in mouth opening and closing movements. This system will be helpful to clinicians when it is difficult to obtain information through MRI.

A fully automated method of human identification based on dental panoramic radiographs using a convolutional neural network.

OBJECTIVES: This study aimed to develop a fully automated human identification method based on a convolutional neural network (CNN) with a large-scale dental panoramic radiograph (DPR) data set. METHODS: In total, 2760 DPRs from 746 subjects who had 2-17 DPRs with various changes in image characteristics due to various dental treatments (tooth extraction, oral surgery, prosthetics, orthodontics, or tooth development) were collected. The test data set included the latest DPR of each subject (746 images) and the other DPRs (2014 images) were used for model training. A modified VGG16 model with two fully connected layers was applied for human identification. The proposed model was evaluated with rank-1, -3, and -5 accuracies, running time, and gradient-weighted class activation mapping (Grad-CAM)-applied images. RESULTS: This model had rank-1, -3, and -5 accuracies of 82.84%, 89.14%, and 92.23%, respectively. All rank-1 accuracy values of the proposed model were above 80% regardless of changes in image characteristics. The average running time to train the proposed model was 60.9 s per epoch, and the prediction time for 746 test DPRs was short (3.2 s/image). The Grad-CAM technique verified that the model automatically identified humans by focusing on identifiable dental information. CONCLUSION: The proposed model showed good performance in fully automatic human identification despite differing image characteristics of DPRs acquired from the same patients. Our model is expected to assist in the fast and accurate identification by experts by comparing large amounts of images and proposing identification candidates at high speed.

KAI1(CD82) is a key molecule to control angiogenesis and switch angiogenic milieu to quiescent state.

BACKGROUND: Little is known about endogenous inhibitors of angiogenic growth factors. In this study, we identified a novel endogenous anti-angiogenic factor expressed in pericytes and clarified its underlying mechanism and clinical significance. METHODS: Herein, we found Kai1 knockout mice showed significantly enhanced angiogenesis. Then, we investigated the anti-angiogenic roll of Kai1 in vitro and in vivo. RESULTS: KAI1 was mainly expressed in pericytes rather than in endothelial cells. It localized at the membrane surface after palmitoylation by zDHHC4 enzyme and induced LIF through the Src/p53 pathway. LIF released from pericytes in turn suppressed angiogenic factors in endothelial cells as well as in pericytes themselves, leading to inhibition of angiogenesis. Interestingly, KAI1 had another mechanism to inhibit angiogenesis: It directly bound to VEGF and PDGF and inhibited activation of their receptors. In the two different in vivo cancer models, KAI1 supplementation significantly inhibited tumor angiogenesis and growth. A peptide derived from the large extracellular loop of KAI1 has been shown to have anti-angiogenic effects to block the progression of breast cancer and retinal neovascularization in vivo. CONCLUSIONS: KAI1 from PC is a novel molecular regulator that counterbalances the effect of angiogenic factors.

Application of a fully deep convolutional neural network to the automation of tooth segmentation on panoramic radiographs.

OBJECTIVES: To evaluate a fully deep learning mask region-based convolutional neural network (R-CNN) method for automated tooth segmentation using individual annotation of panoramic radiographs. STUDY DESIGN: In total, 846 images with tooth annotations from 30 panoramic radiographs were used for training, and 20 panoramic images as the validation and test sets. An oral radiologist manually performed individual tooth annotation on the panoramic radiographs to generate the ground truth of each tooth structure. We used the augmentation technique to reduce overfitting and obtained 1024 training samples from 846 original data points. A fully deep learning method using the mask R-CNN model was implemented through a fine-tuning process to detect and localize the tooth structures. For performance evaluation, the F1 score, mean intersection over union (IoU), and visual analysis were utilized. RESULTS: The proposed method produced an F1 score of 0.875 (precision: 0.858, recall: 0.893) and a mean IoU of 0.877. A visual evaluation of the segmentation method showed a close resemblance to the ground truth. CONCLUSIONS: The method achieved high performance for automation of tooth segmentation on dental panoramic images. The proposed method might be applied in the first step of diagnosis automation and in forensic identification, which involves similar segmentation tasks.

Herpesviruses induce aggregation and selective autophagy of host signalling proteins NEMO and RIPK1 as an immune-evasion mechanism.

Viruses manipulate cellular signalling by inducing the degradation of crucial signal transducers, usually via the ubiquitin-proteasome pathway. Here, we show that the murine cytomegalovirus (Murid herpesvirus 1) M45 protein induces the degradation of two cellular signalling proteins, the nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) essential modulator (NEMO) and the receptor-interacting protein kinase 1 (RIPK1), via a different mechanism: it induces their sequestration as insoluble protein aggregates and subsequently facilitates their degradation by autophagy. Aggregation of target proteins requires a distinct sequence motif in M45, which we termed 'induced protein aggregation motif'. In a second step, M45 recruits the retromer component vacuolar protein sorting 26B (VPS26B) and the microtubule-associated protein light chain 3 (LC3)-interacting adaptor protein TBC1D5 to facilitate degradation of aggregates by selective autophagy. The induced protein aggregation motif is conserved in M45-homologous proteins of several human herpesviruses, including herpes simplex virus, Epstein-Barr virus and Kaposi's sarcoma-associated herpesvirus, but is only partially conserved in the human cytomegalovirus UL45 protein. We further show that the HSV-1 ICP6 protein induces RIPK1 aggregation and degradation in a similar fashion to M45. These data suggest that induced protein aggregation combined with selective autophagy of aggregates (aggrephagy) represents a conserved viral immune-evasion mechanism.

Transient meiotic arrest maintained by DON (6-diazo-5-oxo-l-norleucine) enhances nuclear/cytoplasmic maturation of porcine oocytes.

The developmental competence of in vitro-matured oocytes is still lower than that of the in vivo-matured oocytes due to precocious meiotic resumption and inappropriate cytoplasmic maturation. Although numerous efforts have been attempted to accomplish better in vitro maturation (IVM) condition, only limited progress has been achieved. Thus, a current study was conducted to examine the effects of 6-diazo-5-oxo-l-norleucine (DON, an inhibitor of hyaluronan synthesis) during the first half period of IVM on nuclear/cytoplasmic maturation of porcine oocytes and subsequent embryonic development. Based on the observation of the nucleus pattern, metaphase II (MII) oocyte production rate in 1 µM DON group was significantly higher than other groups at 44 h of IVM. The 1 µM of DON was suggested to be optimal for porcine IVM and was therefore used for further investigation. Meiotic arrest effect of DON was maximal at 6 h of IVM, which was supported by the maintenance of significantly higher intra-oocyte cAMP level. In addition, increased pERK1/2 levels and clear rearrangement of cortical granules in membrane of MII oocytes matured with DON provided the evidence for balanced meiosis progression between nuclear and cytoplasmic maturation. Subsequently, DON significantly improved blastocyst formation rate, total cell numbers, and cellular survival in blastocysts after parthenogenetic activation, in vitro fertilization, and somatic cell nuclear transfer. Altogether, our results showed for the first time that 1 µM DON can be used to increase the yield of developmentally competent MII oocytes by synchronizing nuclear/cytoplasmic maturation, and it subsequently improves embryo developmental competence.

Site-specific and time-course changes of postmenopausal osteoporosis in rat mandible: comparative study with femur.

Although the effects of osteoporosis on the skeleton are well studied, site-specific and long-term studies on the mandible are still lacking. This study investigated the time-course changes of the bone microarchitecture in the mandibular condyle in comparison to the corresponding changes in the alveolar bone, body of the mandible, and femur. Thirty-six 11-week-old female Sprague-Dawley rats were divided into ovariectomized (OVX) (24 rats) and sham (12 rats) groups. The right femur and mandible were obtained from 6 OVX rats and 3 sham rats at 8, 12, 26, and 36 weeks after surgery, respectively. The histomorphometric analysis was performed using micro-computed tomography and histologic assessments from the (1) distal femur; (2) the alveolar bone and (3) the body of the mandible; (4) the subchondral and (5) the central region of the condyle. The Brown-Forsythe test was used to verify the assumptions for statistical analysis, and the Mann-Whitney U test was then performed. The mandibular condyle showed increased trabecular bone in both the OVX and sham groups, while the bone density was reduced in the distal femur and the mandible interradicular septum and body. When comparing the OVX group to the sham group, only the central condyle showed a significant reduction in bone density at 36 weeks. Osteoporosis behaves in different manners in different parts of the skeleton, and clinicians should be aware that patients displaying osteoporotic changes in the mandible are expected to show severely advanced bone mineral density reduction in other bones, such as the femur.

Comparative Evaluation of Hormones and Hormone-Like Molecule in Lineage Specification of Human Induced Pluripotent Stem Cells.

BACKGROUND AND OBJECTIVES: Proficient differentiation of human pluripotent stem cells (hPSCs) into specific lineages is required for applications in regenerative medicine. A growing amount of evidences had implicated hormones and hormone-like molecules as critical regulators of proliferation and lineage specification during in vivo development. Therefore, a deeper understanding of the hormones and hormone-like molecules involved in cell fate decisions is critical for efficient and controlled differentiation of hPSCs into specific lineages. Thus, we functionally and quantitatively compared the effects of diverse hormones (estradiol 17-ß (E2), progesterone (P4), and dexamethasone (DM)) and a hormone-like molecule (retinoic acid (RA)) on the regulation of hematopoietic and neural lineage specification. METHODS AND RESULTS: We used 10 nM E2, 3 µM P4, 10 nM DM, and 10 nM RA based on their functional in vivo developmental potential. The sex hormone E2 enhanced functional activity of hematopoietic progenitors compared to P4 and DM, whereas RA impaired hematopoietic differentiation. In addition, E2 increased CD34+CD45+ cells with progenitor functions, even in the CD43- population, a well-known hemogenic marker. RA exhibited lineage-biased potential, preferentially committing hPSCs toward the neural lineage while restricting the hematopoietic fate decision. CONCLUSIONS: Our findings reveal unique cell fate potentials of E2 and RA treatment and provide valuable differentiation information that is essential for hPSC applications.

GDNF family receptor alpha 1 is a reliable marker of undifferentiated germ cells in bulls.

Undifferentiated germ cells, including spermatogonial stem cells (SSCs), make up only a very small proportion of germ cells within the testis; for example, 0.03% of germ cells in the mouse testis are SSCs. In this study, we investigated the characteristics of bovine undifferentiated germ cells and developed an enrichment procedure for these cells on the basis of fluorescence-activated cell sorting (FACS), using the specific cell surface marker glial cell line-derived neurotrophic factor family receptor alpha 1 (GFRα1). FACS analysis showed that only 0.6% of the total testicular cells were GFRα1-positive. These GFRα1-positive cells had a significantly higher expression of UCHL1, ZBTB16, and DDX4 (all markers of undifferentiated spermatogonial and germ cells) than that of fresh testicular cells. Quantitative reverse-transcription PCR analyses also indicated that the gene expression of BCL6B and NANOS2 was significantly higher in GFRα1-positive cells. Furthermore, xenogeneic transplantation of bovine testicular cells into immunodeficient mice resulted in 4.4-fold more colonies of GFRα1-positive cells than those of fresh testicular cells, indicating that FACS with antibodies to GFRα1 had efficiently enriched putative SSCs from total testicular cells. Collectively, these results demonstrate that GFRα1 could be used as a marker of bovine undifferentiated germ cells, including putative SSCs, and that its expression on SSCs has important implications for the further development of techniques for enriching stem cells from other species.

Novel crosstalk between Vps26a and Nox4 signaling during neurogenesis.

Despite numerous studies on the molecular switches governing the conversion of stemness to differentiation in embryonic stem cells (ESCs), little is known about the involvement of the retromer complex. Under neural differentiation conditions, Vps26a deficiency (Vps26a-/-) or knockdown suppressed the loss of stemness and subsequent neurogenesis from ESCs or embryonic carcinoma cells, respectively, as evidenced by the long-lasting expression of stemness markers and the slow appearance of neuronal differentiation markers. Interestingly, relatively low reactive oxygen species (ROS) levels were generated during differentiation of Vps26a-/- ESCs, and treatment with an antioxidant or inhibitor of NADPH oxidase (Nox), a family of ROS-generating enzymes, led to restoration of stemness in wild-type cells to the level of Vps26a-/- cells during neurogenesis. Importantly, a novel interaction between Vps26a and Nox4 linked to the activation of ERK1/2 depended highly on ROS levels during neurogenesis, which were strongly suppressed in differentiating Vps26a-/- ESCs. Moreover, inhibition of phosphorylated ERK1/2 (pERK1/2) resulted in decreased ROS and Nox4 levels, indicating the mutual dependency between pERK1/2 and Nox4-derived ROS during neurogenesis. These results suggest that Vps26a regulates stemness by actively cooperating with the Nox4/ROS/ERK1/2 cascade during neurogenesis. Our findings have important implications for understanding the regulation of stemness via crosstalk between the retromer molecule and redox signaling, and may contribute to the development of ESC-based therapeutic strategies for the mass production of target cells.

The effects of kinase modulation on in vitro maturation according to different cumulus-oocyte complex morphologies.

Successful production of transgenic pigs requires oocytes with a high developmental competence. However, cumulus-oocyte complexes (COCs) obtained from antral follicles have a heterogeneous morphology. COCs can be classified into one of two classes: class I, with five or more layers of cumulus cells; and class II, with one or two layers of cumulus cells. Activator [e.g., epidermal growth factor (EGF)] or inhibitors (e.g., wortmannin and U0126) are added to modulate kinases in oocytes during meiosis. In the present study, we investigated the effects of kinase modulation on nuclear and cytoplasmic maturation in COCs. Class I COCs showed a significantly higher developmental competence than class II COCs. Moreover, the expression of two kinases, AKT and ERK, differed between class I and class II COCs during in vitro maturation (IVM). Initially, inhibition of the PI3K/AKT signaling pathway in class I COCs during early IVM (0-22 h) decreased developmental parameters, such as blastocyst formation rate, blastomere number, and cell survival. Conversely, EGF-mediated AKT activation in class II COCs enhanced developmental capacity. Regarding the MAPK signaling pathway, inhibition of ERK by U0126 in class II COCs during early IVM impaired developmental competence. However, transient treatment with U0126 in class II COCs increased oocyte maturation and AKT activity, improving embryonic development. Additionally, western blotting showed that inhibition of ERK activity negatively regulated the AKT signaling pathway, indicative of a relationship between AKT and MAPK signaling in the process underlying meiotic progression in pigs. These findings may help increase the developmental competence and utilization rate of pig COCs with regard to the production of transgenic pigs and improve our understanding of kinase-associated meiosis events.

Chemotherapeutic Drugs Alter Functional Properties and Proteome of Mouse Testicular Germ Cells In Vitro.

Many of the testicular cancer-survived patients, treated with chemotherapeutic drugs, show infertility, pre and postimplantation loss, and germ cell abnormality. Studies examining the negative effects of chemotherapeutic drugs on testicular germ cells are ongoing; however, information on the stemness properties and proteomic profiles of these cells are lacking. This study investigated the effects of chemotherapeutic drugs etoposide, cisplatin, bleomycin, and their combination (BEP) on the physiology and stem cell activity of mouse germ cells in vitro. Our results showed that treatment with the abovementioned drugs affected germ cell viability and decreased the number of proliferating germ cells significantly at specific concentrations (0.05 µM etoposide, 1 µM cisplatin, 10 µM bleomycin, and 0.1 µM BEP), which maintained a survival rate of >90%. We also observed a significantly higher percentage of apoptotic cells and alterations in the expression of undifferentiated and differentiated spermatogonia-related genes and marker proteins in germ cells exposed to abovementioned concentrations of the drugs. Next, we performed germ cell transplantation into recipient mice and observed a remarkable reduction in stemness properties of spermatogonial stem cells at these concentrations. Based on these results, we assessed the levels of differentially expressed proteins by performing proteomic analysis. We found that treatment with the abovementioned drugs induced cell damage, oxidative stress, metabolic disruption, and immune deficiency which may promote tumor regeneration, cytotoxicity, infertility, and transgenerational cellular function transmission. Thus, this study provides information about the chemotherapy-induced recurrent destruction and thereby can lead possible changes in medication.

A Phytochemical Approach to Promotion of Self-renewal in Murine Spermatogonial Stem Cell by Using Sedum Sarmentosum Extract.

Spermatogonial stem cells (SSCs) are the basis of spermatogenesis, which is dependent on the ability to self-renew and differentiation. Controlling self-renewal and differentiation of SSCs could apply to treatment of disease such as male infertility. Recently, in the field of stem cell research, it was demonstrated that effective increase in stem cell activity can be achieved by using growth factors derived from plant extracts. In this study, our aim is to investigate components from natural plant to improve the self-renewal of SSCs. To find the components, germ cells were cultured with comprehensive natural plant extracts, and then the more pure fraction, and finally single compound at different concentrations. As a result, we found 5H-purin-6-amine at 1 µg/mL, originated from Sedum sarmentosum, was a very effective compound induced SSCs proliferation. Our data showed that germ cells cultured with 5H-purin-6-amine could maintain their stable characteristics. Furthermore, transplantation results demonstrated that 5H-purin-6-amine at 1 µg/mL increased the activity of SSCs, indicating the compound could increase true SSC concentration within germ cells to 1.96-fold. These findings would be contributed to improve further reproductive research and treat male infertility by using natural plant extracts.

Alu-Derived Alternative Splicing Events Specific to Macaca Lineages in CTSF Gene.

Cathepsin F, which is encoded by CTSF, is a cysteine proteinase ubiquitously expressed in several tissues. In a previous study, novel transcripts of the CTSF gene were identified in the crab-eating monkey deriving from the integration of an Alu element-AluYRa1. The occurrence of AluYRa1-derived alternative transcripts and the mechanism of exonization events in the CTSF gene of human, rhesus monkey, and crab-eating monkey were investigated using PCR and reverse transcription PCR on the genomic DNA and cDNA isolated from several tissues. Results demonstrated that AluYRa1 was only integrated into the genome of Macaca species and this lineage-specific integration led to exonization events by producing a conserved 3' splice site. Six transcript variants (V1-V6) were generated by alternative splicing (AS) events, including intron retention and alternative 5' splice sites in the 5' and 3' flanking regions of CTSF_AluYRa1. Among them, V3-V5 transcripts were ubiquitously expressed in all tissues of rhesus monkey and crab-eating monkey, whereas AluYRa1-exonized V1 was dominantly expressed in the testis of the crab-eating monkey, and V2 was only expressed in the testis of the two monkeys. These five transcript variants also had different amino acid sequences in the C-terminal region of CTSF, as compared to reference sequences. Thus, species-specific Alu-derived exonization by lineage-specific integration of Alu elements and AS events seems to have played an important role during primate evolution by producing transcript variants and gene diversification.

Iloprost supports early development of in vitro-produced porcine embryos through activation of the phosphatidylinositol 3-kinase/AKT signalling pathway.

Despite evidence of the presence of prostaglandin (PG) I2 in mammalian oviducts, its role in early development of in vitro-produced (IVP) embryos is largely unknown. Thus, in the present study we examined the effects of iloprost, a PGI2 analogue, on the in vitro developmental competence of early porcine embryos and the underlying mechanism(s). To examine the effects of iloprost on the development rate of IVF embryos, iloprost was added to the in vitro culture (IVC) medium and cultured for 6 days. Supplementation of the IVC medium with iloprost significantly improved developmental parameters, such as blastocyst formation rate, the trophectoderm:inner cell mass ratio and cell survival in IVF and parthenogenetically activated (PA) embryos. In addition, post-blastulation development into the expanded blastocyst stage was improved in iloprost-treated groups compared with controls. Interestingly, the phosphatidylinositol 3-kinase (PI3K)/AKT signalling pathway was significantly activated by iloprost supplementation in a concentration-dependent manner (10-1000nM), and the beneficial effects of iloprost on the early development of porcine IVF and PA embryos was completely ablated by treatment with 2.5µM wortmannin, a PI3K/AKT signalling inhibitor. Importantly, expression of the PI3K/AKT signalling pathway was significantly reduced in somatic cell nuclear transfer (SCNT) compared with IVF embryos, and iloprost supported the early development of SCNT embryos, as was the case for IVF and PA embryos, suggesting a consistent effect of iloprost on the IVC of IVP porcine embryos. Together, these results indicate that iloprost can be a useful IVC supplement for production of IVP early porcine embryos with high developmental competence.

Antioxidant and anti-ageing activities of citrus-based juice mixture.

The production of excessive reactive oxygen species by exposure to oxidative stress and solar radiation are primary factors in skin damage. We examined the effects of a citrus-based juice mixture and its bioactive compounds on antioxidant and anti-ageing activities in human dermal fibroblasts and hairless mice via the regulation of antioxidant enzymes and the mitogen-activated protein kinase pathway. The citrus-based juice mixture reduced H2O2-induced cell damage and intracellular reactive oxygen species production in human dermal fibroblasts. Citrus-based juice mixture pretreatment suppressed the activation of the H2O2-mediated mitogen-activated protein kinase pathway by activating the expression of activator protein 1 and matrix metalloproteinases. Moreover, it increased the expression levels of antioxidant enzymes such as glutathione reductase, catalase and manganese superoxide dismutase. In addition, oral administration of the citrus-based juice mixture decreased skin thickness and wrinkle formation and increased collagen content on an ultraviolet light B-exposed hairless mouse. These results indicate that the citrus-based juice mixture is a potentially healthy beverage for the prevention of oxidative stress-induced premature skin ageing.

Characterization of Cerebral Damage in a Monkey Model of Alzheimer's Disease Induced by Intracerebroventricular Injection of Streptozotocin.

In line with recent findings showing Alzheimer's disease (AD) as an insulin-resistant brain state, a non-transgenic animal model with intracerebroventricular streptozotocin (icv-STZ) administration has been proposed as a representative experimental model of AD. Although icv-STZ rodent models of AD have been increasingly researched, studies in non-human primate models are very limited. In this study, we aimed to characterize the cerebral damage caused by icv-STZ in non-human primates; to achieve this, three cynomolgus monkeys (Macaca fascicularis) were administered four dosages of STZ (2 mg/kg) dissolved in artificial cerebrospinal fluid and another three controls were injected with only artificial cerebrospinal fluid at the cerebellomedullary cistern. In vivo neuroimaging was performed with clinical 3.0 T MRI, followed by quantitative analysis with FSL for evaluation of structural changes of the brain. Immunohistochemistry was performed to evaluate cerebral histopathology. We showed that icv-STZ caused severe ventricular enlargement and parenchymal atrophy, accompanying amyloid-ß deposition, hippocampal cell loss, tauopathy, ependymal cell loss, astrogliosis, and microglial activation, which are observed in human aged or AD brain. The findings suggest that the icv-STZ monkey model would be a valuable resource to study the mechanisms and consequences of a variety of cerebral pathologies including major pathological hallmarks of AD. Furthermore, the study of icv-STZ monkeys could contribute to the development of treatments for age- or AD-associated cerebral changes.