Basic Fibroblast Growth Factor Activates MEK/ERK Cell Signaling Pathway and Stimulates the Proliferation of Chicken Primordial Germ Cells

BACKGROUND: Long-term maintenance of avian primordial germ cells (PGCs) in vitro has tremendous potential because it can be used to deepen our understanding of the biology of PGCs. A transgenic bioreactor based on the unique migration of PGCs toward the recipients' sex cord via the bloodstream and thereby creating a germline chimeric bird has many potential applications. However, the growth factors and the signaling pathway essential for inducing proliferation of chicken PGCs are unknown. METHODOLOGY/PRINCIPAL FINDINGS: Therefore, we conducted this study to investigate the effects of various combinations of growth factors on the survival and proliferation of PGCs under feeder-free conditions. We observed proliferation of PGCs in media containing bFGF. Subsequent characterization confirmed that the cultured PGCs maintained expression of PGC-specific markers, telomerase activity, normal migrational activity, and germline transmission. We also found that bFGF activates the mitogen-activated protein kinase kinase/extracellular-signal regulated kinase (MEK/ERK) signaling. Also, the expression of 133 transcripts was reversibly altered by bFGF withdrawal. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that chicken PGCs can be maintained in vitro without any differentiation or dedifferentiation in feeder free culture conditions, and subsequent analysis revealed that bFGF is one of the key factors that enable proliferation of chicken PGCs via MEK/ERK signaling regulating downstream genes that may be important for PGC proliferation and survival

New Era of Air Quality Monitoring from Space: Geostationary Environment Monitoring Spectrometer (GEMS)

GEMS will monitor air quality over Asia at unprecedented spatial and temporal resolution from GEO for the first time, providing column measurements of aerosol, ozone and their precursors (nitrogen dioxide, sulfur dioxide and formaldehyde). Geostationary Environment Monitoring Spectrometer (GEMS) is scheduled for launch in late 2019 - early 2020 to monitor Air Quality (AQ) at an unprecedented spatial and temporal resolution from a Geostationary Earth Orbit (GEO) for the first time. With the development of UV-visible spectrometers at sub-nm spectral resolution and sophisticated retrieval algorithms, estimates of the column amounts of atmospheric pollutants (O3, NO2, SO2, HCHO, CHOCHO and aerosols) can be obtained. To date, all the UV-visible satellite missions monitoring air quality have been in Low Earth orbit (LEO), allowing one to two observations per day. With UV-visible instruments on GEO platforms, the diurnal variations of these pollutants can now be determined. Details of the GEMS mission are presented, including instrumentation, scientific algorithms, predicted performance, and applications for air quality forecasts through data assimilation. GEMS will be onboard the GEO-KOMPSAT-2 satellite series, which also hosts the Advanced Meteorological Imager (AMI) and Geostationary Ocean Color Imager (GOCI)-2. These three instruments will provide synergistic science products to better understand air quality, meteorology, the long-range transport of air pollutants, emission source distributions, and chemical processes. Faster sampling rates at higher spatial resolution will increase the probability of finding cloud-free pixels, leading to more observations of aerosols and trace gases than is possible from LEO. GEMS will be joined by NASA's TEMPO and ESA's Sentinel-4 to form a GEO AQ satellite constellation in early 2020s, coordinated by the Committee on Earth Observation Satellites (CEOS)

Association between Decreased ITGA7 Levels and Increased Muscle α-Synuclein in an MPTP-Induced Mouse Model of Parkinson’s Disease

Parkinson's disease (PD) is a neurodegenerative disease characterized by the loss of dopaminergic neurons in the substantia nigra (SN), reducing dopaminergic levels in the striatum and affecting motor control. Herein, we investigated the potential relationship between integrin α7 (ITGA7) and α-synuclein (α-syn) in the muscle of methyl-4-phenyl-1,2,3,6 tetrahydropyridine (MPTP)-induced mice and C2C12 cells. To characterize the pathology of PD, we examined the expression of tyrosine hydroxylase (TH) in the SN of the midbrain. Compared with the control group, MPTP-treated mice showed a significant decrease in TH expression in the SN, accompanied by a significant decrease in muscle ITGA7 expression. Compared with the control group, α-syn expression was increased in the MPTP group. Furthermore, the pattern of α-syn expression in the MPTP group was similar to the ITGA7 expression pattern in the control group (linear forms). To determine the relationship between ITGA7 and PD, we examined the expression of ITGA7 and α-syn after ITGA7 knockdown using siRNA in C2C12 cells. ITGA7 expression significantly decreased while α-syn expression significantly increased in siRNA-treated C2C12 cells. These results suggest that decreased ITGA7 muscle expression could increase α-syn expression. Moreover, α-syn accumulation, induced by decreased muscle ITGA7, might contribute to PD pathology

Decrease in ITGA7 Levels Is Associated with an Increase in α-Synuclein Levels in an MPTP-Induced Parkinson’s Disease Mouse Model and SH-SY5Y Cells

We investigated the potential association between integrin α7 (ITGA7) and alpha-synuclein (α-syn) in a methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson’s disease (PD) mouse model. Tyrosine hydroxylase (TH), ITGA7, and α-syn expression in the substantia nigra (SN) of the brain were observed to examine the pathological characteristics of PD. To determine the relationship between ITGA7 and PD, the expression of TH and α-syn was investigated after ITGA7 siRNA knockdown in SH-SY5Y cells. The ITGA7 microarray signal was decreased in the SN of the MPTP group, indicating reduced ITGA7 expression compared to that in the control. The expression patterns of ITGA7 in the control group and those of α-syn in the MPTP group were similar on immunohistochemical staining. Reduction in ITGA7 expression by ITGA7 siRNA administration induced a decrease in TH expression and an increase in α-syn expression in SH-SY5Y cells. The decreased expression of ITGA7 significantly decreased the expression of bcl2 and increased the bax/bcl2 ratio in SH-SY5Y cells. These results suggest that reduced ITGA7 expression may be related to increased α-syn expression and apoptosis of dopaminergic cells in an MPTP-induced PD mouse model. To the best of our knowledge, this is the first study to show an association between ITGA7 and PD

Adiponectin affects the migration ability of bone marrow-derived mesenchymal stem cells via the regulation of hypoxia inducible factor 1α

Abstract Background Bone marrow (BM) is progressively filled with adipocytes during aging process. Thus, BM adipocytes-derived adiponectin (APN) affects the function of bone marrow-derived mesenchymal stem cells (BMSCs). However, little is known about the effect of APN on migration ability of BMSCs cultured under hypoxic conditions, which is similar to the BM microenvironment. Results We found that the population and migration ability of BMSCs from APN KO mice was higher than that of WT mice due to increased stability of hypoxia inducible factor 1α (HIF1α). Stem cell factor (SCF)-activated STAT3 stimulated the induction of HIF1α which further stimulated SCF production, indicating that the SCF/STAT3/HIF1α positive loop was highly activated in the absence of APN. It implies that APN negatively regulated this positive loop by stimulating HIF1α degradation via the inactivation of GSK3β. Furthermore, APN KO BMSCs were highly migratory toward EL-4 lymphoma, and the interaction between CD44 in BMSCs and hyaluronic acid (HA) from EL-4 enhanced the migration of BMSCs. On the other hand, the migrated BMSCs recruited CD8+ T cells into the EL-4 tumor tissue, resulting in the retardation of tumor growth. Additionally, gradually increased APN in BM on the aging process affects migration and related functions of BMSCs, thus aged APN KO mice showed more significant suppression of EL-4 growth than young APN KO mice due to higher migration and recruitment of CD8+ T cells. Conclusion APN deficiency enhances CD44-mediated migration ability of BMSCs in the hypoxic conditions by the SCF/STAT3/HIF1α positive loop and influences the migration ability of BMSCs for a longer time depending on the aging process. Video Abstrac

Bauxite residue neutralisation precipitate stability in acidic environments

This investigation used a combination of techniques, such as X-ray diffraction, inductively coupled plasma optical emission spectroscopy and infrared spectroscopy, to determine the dissolution mechanisms of the Bayer precipitate and the associated rate of dissolution in acetic, citric and oxalic acid environments. The Bayer precipitate is a mixture of hydrotalcite, calcium carbonate and sodium chloride that forms during the seawater neutralisation of Bayer liquors (waste residue of the alumina industry). The dissolution rate of a Bayer precipitate is found to be dependent on (1) the strength of\ud the organic acid and (2) the number of donating H+ ions. The dissolution mechanism for a Bayer precipitate consists\ud of several steps involving: (1) the dissolution of CaCO3, (2) formation of whewellite (calcium oxalate) when oxalic acid is used and (3) multiple dissolution steps for hydrotalcite that are highly dependent on the pH of solution. The decomposition of the Al–OH hydrotalcite layers resulted in the immediate formation of Al(OH)3, which is stable until the pH decreases below 5.5. This investigation has found that the Bayer precipitate is stable across a wide pH range in the presence of common organic acids found in the rhizosphere, and that initial decomposition steps are likely to be beneficial in supporting plant growth through the release of nutrients such as Ca2þ and Mg2þ

A preliminary study: novelty seeking, frontal executive function, and dopamine receptor (D2) TaqI A gene polymorphism in patients with methamphetamine dependence

INTRODUCTION: Dopamine receptor polymorphisms have been associated with specific patterns of novelty seeking (NS) temperamental nature and frontal executive function. In addition, carriers of dopamine receptor type 2 (DRD2)-TaqI A1 have been hypothesized to be potentially vulnerable to addictive behaviors. In the present study, the association between dopamine D2 polymorphisms, NS, and frontal executive function was studied. METHODS: Thirty-seven methamphetamine (MA)-dependent subjects and 40 healthy comparison subjects participated in the current study. The severity of addiction, NS temperament, and frontal executive functions were measured using the Addiction Severity Index, the NS subscale in the Temperament and Character Inventory, and the Wisconsin Card Sorting Test, respectively. All subjects were genotyped with regard to DRD2-TaqI polymorphisms. RESULTS: The prevalence of DRD2-TaqI A1 allele polymorphisms was greater in the MA-abuser group than in the comparison group. Patients with MA dependence also had higher NS characteristics and high scores in total trials, errors, and perseverative errors of the Wisconsin Card Sorting Test than comparison subjects. Within patients with MA dependence, the subgroup of DRD2-TaqI A1 carrier had greater NS scores relative to those without, whereas there was only a trend level of lower frontal executive function in the first subgroup. CONCLUSION: In the present study, the MA-dependent patients with DRD2-TaqI A1 allele had significantly greater NS scores and lower frontal executive function with a trend level than those without. These preliminary results suggest that MA-dependent patients may have the possibility of genetic and biogenic vulnerability to MA

Versatile Hole Selective Molecules Containing a Series of Heteroatoms as Self-Assembled Monolayers for Efficient p-i-n Perovskite and Organic Solar Cells

Inverted type perovskite solar cells (PSCs) have recently emerged as a major focus in academic and industrial photovoltaic research. Their multiple advantages over conventional PSCs include easy processing, hysteresis-free behavior, high stability, and compatibility for tandem applications. However, the maximum power conversion efficiency (PCE) of inverted PSCs still lags behind those of conventional PSCs because suitable charge-selective materials for inverted PSCs are limited. In this work, excellent hole-selective materials for inverted PSCs are introduced. A series of tricyclic aromatic rings containing O, S, or Se, respectively, as a core heteroatom, along with a phosphonic acid anchor, form a self-assembled monolayer (SAM) that directly contacts the perovskite absorber. The influence of heteroatoms in the aromatic structure on the molecular energetics and operating characteristics of the corresponding inverted PSCs is investigated using complementary experimental techniques as well as density functional theory (DFT) calculations. It is found that all of the SAMs formed an energetically well-aligned interface with the perovskite absorber. The interaction energy between the Se-containing SAM and perovskite absorber is the strongest among the series and it reduces the interfacial defect density, in turn leading to an extended charge carrier lifetime. As a result, PSCs incorporating the Se-containing SAM achieves a PCE of 22.73% and retains approximate to 96% of their initial efficiency after a maximum power point tracking test of 500 h without encapsulation under ambient conditions. All of the SAMs are then employed in organic solar cells (OSCs). Again, the Se-containing SAM-based OSCs demonstrates the highest PCE of 17.9% among the three molecular SAM-based OSCs. This work demonstrates the great potential for precisely engineered SAMs for use in high-performance solar cells