Neurons and glia of the peripheral nervous system are derived from progenitor cell populations, originating from embryonic neural crest. The neural crest and vasculature are intimately associated ...during embryonic development and in the mature central nervous system, in which they form a neurovascular unit comprised of neurons, glia, pericytes, and vascular endothelial cells that play important roles in health and disease. Our group and others have previously reported that postnatal populations of stem cells originating from glia or Schwann cells possess neural stem cell qualities, including rapid proliferation and differentiation into mature glia and neurons. Bone marrow receives sensory and sympathetic innervation from the peripheral nervous system and is known to contain myelinating and unmyelinating Schwann cells. Herein, we describe a population of neural crest-derived Schwann cells residing in a neurovascular niche of bone marrow in association with nerve fibers. These Schwann cells can be isolated and expanded. They demonstrate plasticity in vitro, generating neural stem cells that exhibit neurogenic potential and form neural networks within the enteric nervous system in vivo following transplantation to the intestine. These cells represent a novel source of autologous neural stem cells for the treatment of neurointestinal disorders.
Dicer is an evolutionarily conserved ribonuclease III that is necessary for microRNA (miRNA) processing and the synthesis of small interfering RNAs from long double-stranded RNA. Although it has been ...shown that Dicer plays important roles in the mammalian germline and early embryogenesis, the functions of Dicer-dependent pathways in the somatic cells of the female reproductive tract are unknown. Using a transgenic line in which Cre recombinase is driven by the anti-Müllerian hormone receptor type 2 promoter, we conditionally inactivated Dicer1 in the mesenchyme of the developing Müllerian ducts and postnatally in ovarian granulosa cells and mesenchyme-derived cells of the oviducts and uterus. Deletion of Dicer in these cell types results in female sterility and multiple reproductive defects including decreased ovulation rates, compromised oocyte and embryo integrity, prominent bilateral paratubal (oviductal) cysts, and shorter uterine horns. The paratubal cysts act as a reservoir for spermatozoa and oocytes and prevent embryos from transiting the oviductal isthmus and passing the uterotubal junction to enter the uterus for implantation. Deep sequencing of small RNAs in oviduct revealed down-regulation of specific miRNAs in Dicer conditional knockout females compared with wild type. The majority of these differentially expressed miRNAs are predicted to regulate genes important for Müllerian duct differentiation and mesenchyme-derived structures, and several of these putative target genes were significantly up-regulated upon conditional deletion of Dicer1. Thus, our findings reveal diverse and critical roles for Dicer and its miRNA products in the development and function of the female reproductive tract.
•RSC inactivation impaired retrieval of remotely acquired delay fear conditioning (FC).•RSC inactivation did not impair retrieval of recently acquired delay FC.•RSC inactivation during encoding did ...not impair later retrieval of delay FC.
Prior studies with permanent lesion methods have demonstrated a role for the retrosplenial cortex (RSC) in the retrieval of remotely, but not recently, acquired delay fear conditioning. To extend the generalizability of these prior findings, the present experiments used chemogenetics to temporarily inactivate the RSC during either retrieval or encoding of delay auditory fear conditioning. Inactivation of the RSC at the time of test impaired retrieval of a remotely conditioned auditory cue, but not a recently conditioned one. In addition, inactivation of the RSC during encoding had no impact on freezing during later retrieval testing for both a remotely and recently conditioned auditory cue. These findings indicate that the RSC contributes to the retrieval, but not encoding, of remotely acquired auditory fear conditioning, and suggest it has less of a role in both retrieval and encoding of recently acquired auditory fear conditioning.
Rainwater harvesting being an alternate source in water scarce areas is becoming a common practice. Catchment contact, however, deteriorates the quality of rainwater making it unfit for potable ...purposes. To improve the quality of harvested rainwater, silver was used as antimicrobial agent in this study. Rainwater samples were taken from underground storage tank of a rooftop rainwater harvesting system installed in one of the buildings at Seoul National University, Seoul, South Korea. The target microorganisms (MOs) were Pseudomonas aeruginosa and Escherichia coli which were measured by using plate count method and standard MPN method, respectively. The efficiency of silver disinfection was evaluated at concentrations, ranging from 0.01 to 0.1mg/l; the safe limit approved by WHO. The experiments were performed for 168h with different time intervals to evaluate the parameters including inactivation rate, residual effect of silver and re-growth in both MOs at lower (i.e. 0.01–0.04mg/l) as well as the higher concentrations of silver (i.e. 0.08–0.1mg/l). Results showed the re-growth in both MOs was only in the case of lower concentrations of silver. The possible reason of re-growth at these concentrations of silver may be the halting of bacterial cell replication process for some time without permanent damage. The kinetics of this study suggest that higher inactivation and long term residual effect towards both MOs can be achieved with the application of silver at 0.08mg/l or higher under safe limit.
► Silver, an effective antimicrobial agent for Pseudomonas aeruginosa and E. coli. ► Higher inactivation and long term residual effect of silver is at 0.08mg/l or higher. ► Re-growth of both MOs is at lower concentrations of silver. ► E. coli is more sensitive to silver than P. aeruginosa. ► Silver disinfection of harvested rainwater, a step ahead towards potable water.
Helical mesoporous silica is synthesized using achiral cationic surfactants as template in a highly concentrated ammonia solution. The particle morphology and the helical pitch of this material could ...be systematically controlled by simply varying the ammonia concentration (see figure). The helical mesoporous silica was characterized by transmission electron microscopy tomography for the first time.
East Asia has experienced rapid development with increasing carbon monoxide (CO) emission in the past decades. Therefore, uplifting CO from the boundary layer to the free troposphere in East Asia can ...have great implications on regional air quality around the world. It can also influence global climate due to the longer lifetime of CO at higher altitudes. In this study, three cases of high CO episodes in the East China Sea and the Sea of Japan from 2003 to 2005 are examined with spaceborne Measurements of Pollution in the Troposphere (MOPITT) data, in combination with aircraft measurements from the Measurement of Ozone and Water Vapor by Airbus In-Service Aircraft (MOZAIC) program. High CO abundances of 300-550 ppbv are observed in MOZAIC data in the free troposphere during these episodes. These are among the highest CO abundances documented at these altitudes. On average, such episodes with CO over 400 ppbv (in the 2003 and 2004 cases) and between 200 and 300 ppbv (in the 2005 case) may occur 2-5 and 10-20% in time, respectively, in the respective altitudes over the region. Correspondingly, elevated CO is shown in MOPITT daytime data in the middle to upper troposphere in the 2003 case, in the lower to middle troposphere in the 2004 case, and in the upper troposphere in the 2005 case. Through analyses of the simulations from a chemical transport model GEOS-Chem and a trajectory dispersion model FLEXPART, we found different CO signatures in the elevated CO and distinct transport pathways and mechanisms for these cases. In the 2003 case, emissions from large forest fires near Lake Baikal dominated the elevated CO, which had been rapidly transported upward by a frontal system from the fire plumes. In the 2004 case, anthropogenic CO from the North China Plain experienced frontal lifting and mostly reached ~ 700 hPa near the East China Sea, while CO from biomass burning over Indochina experienced orographic lifting, lee-side-trough-induced convection, and frontal lifting through two separate transport pathways, leading to two distinct CO enhancements around 700 and 300 hPa. In the 2005 case, the observed CO of ~ 300 ppbv around 300 hPa originated from anthropogenic sources over the Sichuan Basin and the North China Plain and from forest fires over Indochina. The high CO was transported to such altitudes through strong frontal lifting, interacting with convection and orographic lifting. These cases show that topography affects vertical transport of CO in East Asia via different ways, including orographic uplifting over the Hengduan Mountains, assisting frontal lifting in the North China Plain, and facilitating convection in the Sichuan Basin. In particular, topography-induced lee-side troughs over Indochina led to strong convection that assisted CO uplifting to the upper troposphere. This study shows that the new daytime MOPITT near-infrared (NIR) and thermal-infrared (TIR) data (version 5 or above) have enhanced vertical sensitivity in the free troposphere and may help qualitative diagnosis of vertical transport processes in East Asia.
Mesenchymal stem cells are a population of pluripotent cells that can differentiate into epidermal-like cells under certain conditions. Wnt3a can promote the proliferation and differentiation of stem ...cells. However, the role of Wnt3a in the differentiation of human umbilical cord mesenchymal stem cells (hUCMSCs) into epidermal-like cells is unknown.
Third-generation hUCMSCs were cultured in normal medium, epidermal stem cell-conditioned medium, and conditioned medium with added Wnt3a. After culturing for 5 days, the expression of cytokeratin 19 (CK19), an antigen specific for epidermal-like cells, was assessed by immunofluorescence and flow cytometry. The expression of CK19 mRNA was confirmed by reverse transcription-polymerase chain reaction(RT-PCR), and β-catenin expression was detected by western blot.
hUCMSCs differentiated into epidermal-like cells when cultured in conditioned medium as shown by positive immunofluorescence staining for CK19. Flow cytometry showed that the number of cells positive for CK19 in the epidermal stem cell-conditioned medium group was significantly higher than that of control group, but lower than that of the Wnt3a-conditioned group (p < 0.05). RT-PCR showed that the expression level of CK19 mRNA in the conditioned medium group was significantly lower than that of the Wnt3a group (p < 0.01). Westernblots showed that the expression of β-catenin in the conditioned medium group was significantly lower than that of the Wnt3a group (p < 0.01).
These results suggest that Wnt3a can effectively promote the differentiation of hUCMSCs into epidermal-like cells.
To evaluate the possible role of the autonomic (sympathetic) nervous system function among the patients with primary premature ejaculation (PPE) and determine whether there is an etiological basis ...for this condition. We performed sympathetic skin response located in the penis (PSSR) in 52 patients with PPE and 46 normally potent men. The latencies and amplitudes of PSSR were measured. The PSSR waveforms were classified into P type and N type according to the waveform characteristics. The waveform distribution in the PPE patients was not statistically different from that in the control group (P=0.609). Mean latency of the PSSR was significantly shorter in the patients than that in the normally potent men (P<0.001). Mean amplitude of the PSSR was significantly greater in patients than that in the normal men (P<0.001). Patients with PPE have hyperactivity of the sympathetic nervous system, which may be another factor involved in the pathological mechanisms of PPE, and the PSSR is an objective test to evaluate patients with PPE.
Mesenchymal stem cells (MSCs) are a kind of adult stem cells that can be isolated easily from bone marrow, adipose tissue, umbilical cord and many other tissues. MSCs have been shown to specifically ...migrate to inflammatory sites, including tumors, and hold great promise as tumor-specific vectors to deliver antitumor agents. Interferon-α (IFNα) has been used in clinic to treat various types of tumors; however, because of its short half-life, significant therapeutic effects require high doses that often results in serious side effects. Here, we tested whether MSCs continuingly secreting IFNα can exert a persistent antitumor effect and eliminate the side effects associated with high clinical doses of recombinant IFNα. We found that even a small number of IFNα-secreting MSCs could potently halt B16 tumor growth in vivo. The antitumor activity of IFNα-secreting MSCs was largely abolished in immunodeficient mice, an effect largely attributed to natural killer cells and CD8(+) T cells. Therefore, IFNα-secreting MSCs provide an innovative strategy for tumor therapy.
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