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71.
Serotonin (5-HT) sensitive adenylate cyclase in monkey anterior limbic cortex homogenates was further characterized and the effects of antipsychotic drugs and 5-HT anatagonists investigated. Differences in time course for stimulation by agonists and in responsiveness to receptor anatagonists of 5-HT-and dopamine (DA)-stimulated activities, were observed. Also there was an additivity of 5-HT and DA at maximally effective concentrations. Classical 5-HT antagonists blocked the 5-HT sensitive adenylate cyclase with a rank order of potency: methiothepin > cyproheptadine > methysergide. These 5-HT antagonists also effectively inhibited DA sensitive adenylate cyclase. Most antipsychotic drugs tested antagonized 5-HT stimulated activity although these drugs exhibited greater efficacies in blocking DA stimulated activity. Exceptions were molindone which failed to antagonize DA sensitive adenylate cyclase but effectively blocked 5-HT sensitive cyclase and pipamperone which was inactive in both cyclase systems. Haloperidol was a more selective antagonist of the DA sensitive adenylate cyclase than were the other antipsychotic drugs tested. 相似文献
72.
Yeo Cho Yoon Beom Hee Ahn Jin Woo Min Kyung Real Lee Sang Hoon Park Hee Cheol Kang 《Current issues in molecular biology》2022,44(2):845
Human hair follicle dermal papilla cells (HFDPCs) located in hair follicles (HFs) play a pivotal role in hair follicle morphogenesis, hair cycling, and hair growth. Over the past few decades, probiotic bacteria (PB) have been reported to have beneficial effects such as improved skin health, anti-obesity, and immuno-modulation for conditions including atopic dermatitis and inflammatory bowel disease (IBD). PB can secrete 50~150 nm sized extracellular vesicles (EVs) containing microbial DNA, miRNA, proteins, lipids, and cell wall components. These EVs can regulate communication between bacteria or between bacteria and their host. Although numerous biological effects of PB-EVs have been reported, the physiological roles of Leuconostoc holzapfelii (hs-Lh), which is isolated from human scalp tissue, and the extracellular vesicles derived from them (hs-LhEVs) are largely unknown. Herein, we investigated the effects of hs-LhEVs on hair growth in HFDPCs. We show that hs-LhEVs increase cell proliferation, migration, and regulate the cell cycle. Furthermore, hs-LhEVs were found to modulate the mRNA expression of hair-growth-related genes in vitro. These data demonstrate that hs-LhEVs can reduce apoptosis by modulating the cell cycle and promote hair growth by regulation via the Wnt/β-catenin signal transduction pathway. 相似文献
73.
74.
Tae-Ho Kim Gun-Dong KimHyun-Jong Ahn Jeong-Je ChoYong Seek Park Cheung-Seog Park 《Life sciences》2013
Aims
Atopic dermatitis (AD) is a chronic and relapsing inflammatory dermatitis characterized by pruritic and eczematous skin lesions. Here, we investigated the therapeutic effect of the fruit flavonoid naringenin on DNFB induced atopic dermatitis mice model.Main methods
AD-like skin lesion was induced by repetitive skin contact with DNFB in NC/Nga mice and the effects of the fruit flavonoid naringenin were evaluated on the basis of histopathological findings of skin, ear swelling and cytokine production of CD4+T cells.Key findings
Intraperitoneal injection of naringenin for one week after DNFB challenge significantly lowered ear swelling and improved back skin lesions. In addition, naringenin significantly suppressed production of interferon-gamma (IFN-γ) by activated CD4+ T cells and serum IgE level. Furthermore, naringenin reduced DNFB-induced infiltration of eosinophils, mast cells, CD4+ T cells, and CD8+ T cells in skin lesions.Significance
Naringenin may suppress the development of AD-like skin lesions in DNFB-treated NC/Nga mice by reducing IFN-γ production of activated CD4+ T cells, serum IgE levels and infiltration of immune cells to skin lesion. 相似文献75.
MicroRNAs (miRNAs) are small RNA molecules (~ 20–30 nucleotides) that generally act in gene silencing and translational repression through the RNA interference pathway. They generally originate from intergenic genomic regions, but some are found in genomic regions that have been characterized such as introns, exons, and transposable elements (TE). To identify the miRNAs that are derived from palindromic MERs, we analyzed MER paralogs in human genome. The structures of the palindromic MERs were similar to the hairpin structure of miRNA in humans. Three miRNAs derived from MER96 located on chromosome 3, and MER91C paralogs located on chromosome 8 and chromosome 17 were identified in HeLa, HCT116, and HEK293 cell lines. The interactions between these MER-derived miRNAs and AGO1, AGO2, and AGO3 proteins were validated by immunoprecipitation assays. The data suggest that miRNAs derived from transposable elements could widely affect various target genes in the human genome. 相似文献
76.
Eunkyung Kim Ji‐Yun Hwang Eun‐Kyung Woo Sung‐Soo Kim Sangmee Ahn Jo Inho Jo 《Obesity (Silver Spring, Md.)》2005,13(9):1510-1514
Objectives: To establish BMI percentiles and cutoffs for underweight, overweight, and obesity in South Korean schoolgirls. Research Methods and Procedures: A total of 1229 South Korean schoolgirls aged 8 to 18 years were randomly selected to complete a self‐administered questionnaire. BMI charts and cutoffs were constructed after analyzing data from 1107 subjects. Percentile curves were established by the modified LMS method. Results: The percentiles for underweight, overweight, and obesity corresponding to BMI of 18.5, 23.0, and 25.0 kg/m2 at age 18 were the 13.0th percentile, the 77.8th percentile, and the 91.2nd percentile, respectively. The corresponding prevalences of underweight, overweight, and obesity were 12.1, 12.5, and 9.8%, respectively. Discussion: We established for the first time, to our knowledge, new BMI cutoffs for ages 8 to 18 that corresponded to BMIs of 18.5, 23.0, and 25.0 kg/m2 for Asian adults designated by the International Obesity Task Force. These newly established BMI cutoffs might help to estimate the prevalence of overweight and obesity in Asian children. 相似文献
77.
Specific regions within the embryonic midbrain and cerebellum require different levels of FGF signaling during development 总被引:1,自引:0,他引:1
Basson MA Echevarria D Ahn CP Sudarov A Joyner AL Mason IJ Martinez S Martin GR 《Development (Cambridge, England)》2008,135(5):889-898
Prospective midbrain and cerebellum formation are coordinated by FGF ligands produced by the isthmic organizer. Previous studies have suggested that midbrain and cerebellum development require different levels of FGF signaling. However, little is known about the extent to which specific regions within these two parts of the brain differ in their requirement for FGF signaling during embryogenesis. Here, we have explored the effects of inhibiting FGF signaling within the embryonic mouse midbrain (mesencephalon) and cerebellum (rhombomere 1) by misexpressing sprouty2 (Spry2) from an early stage. We show that such Spry2 misexpression moderately reduces FGF signaling, and that this reduction causes cell death in the anterior mesencephalon, the region furthest from the source of FGF ligands. Interestingly, the remaining mesencephalon cells develop into anterior midbrain, indicating that a low level of FGF signaling is sufficient to promote only anterior midbrain development. Spry2 misexpression also affects development of the vermis, the part of the cerebellum that spans the midline. We found that, whereas misexpression of Spry2 alone caused loss of the anterior vermis, reducing FGF signaling further, by decreasing Fgf8 gene dose, resulted in loss of the entire vermis. Our data suggest that cell death is not responsible for vermis loss, but rather that it fails to develop because reducing FGF signaling perturbs the balance between vermis and roof plate development in rhombomere 1. We suggest a molecular explanation for this phenomenon by providing evidence that FGF signaling functions to inhibit the BMP signaling that promotes roof plate development. 相似文献
78.
Chinese hamster ovary (CHO) cells are the main platform for production of biotherapeutics in the biopharmaceutical industry. However, relatively little is known about the metabolism of CHO cells in cell culture. In this work, metabolism of CHO cells was studied at the growth phase and early stationary phase using isotopic tracers and mass spectrometry. CHO cells were grown in fed-batch culture over a period of six days. On days 2 and 4, [1,2-13C] glucose was introduced and the labeling of intracellular metabolites was measured by gas chromatography-mass spectrometry (GC–MS) at 6, 12 and 24 h following the introduction of tracer. Intracellular metabolic fluxes were quantified from measured extracellular rates and 13C-labeling dynamics of intracellular metabolites using non-stationary 13C-metabolic flux analysis (13C-MFA). The flux results revealed significant rewiring of intracellular metabolic fluxes in the transition from growth to non-growth, including changes in energy metabolism, redox metabolism, oxidative pentose phosphate pathway and anaplerosis. At the exponential phase, CHO cell metabolism was characterized by a high flux of glycolysis from glucose to lactate, anaplerosis from pyruvate to oxaloacetate and from glutamate to α-ketoglutarate, and cataplerosis though malic enzyme. At the stationary phase, the flux map was characterized by a reduced flux of glycolysis, net lactate uptake, oxidative pentose phosphate pathway flux, and reduced rate of anaplerosis. The fluxes of pyruvate dehydrogenase and TCA cycle were similar at the exponential and stationary phase. The results presented here provide a solid foundation for future studies of CHO cell metabolism for applications such as cell line development and medium optimization for high-titer production of recombinant proteins. 相似文献
79.
Yang YS Ahn TH Lee JC Moon CJ Kim SH Park SC Chung YH Kim HY Kim JC 《Birth defects research. Part B, Developmental and reproductive toxicology》2007,80(5):374-382
This study investigated the potential adverse effects of tert-butyl acetate (TBAc) on maternal toxicity and embryo-fetal development after maternal exposure of pregnant rats from gestational days 6 through 19. TBAc was administered to pregnant rats by gavage at 0, 400, 800, and 1,600 mg/kg/day. All dams were subjected to a Caesarean section on day 20 of gestation, and their fetuses were examined for any morphological abnormalities. At 1,600 mg/kg, maternal toxicity manifested as increases in the incidence of clinical signs and death, lower body weight gain and food intake, increases in the weights of adrenal glands and liver, and a decrease in thymus weight. Developmental toxicity included a decrease in fetal weight, an increase in the incidence of skeletal variation, and a delay in fetal ossification. At 800 mg/kg, only a minimal developmental toxicity, including an increase in the incidence of skeletal variation and a delay in fetal ossification, were observed. In contrast, no adverse maternal or developmental effects were observed at 400 mg/kg. These results show that a 14-day repeated oral dose of TBAc is embryotoxic at a maternally toxic dose (i.e., 1,600 mg/kg/day) and is minimally embryotoxic at a nonmaternally toxic dose (i.e., 800 mg/kg/day) in rats. However, no evidence for the teratogenicity of TBAc was noted in rats. It is concluded that the developmental findings observed in the present study are secondary effects to maternal toxicity. Under these experimental conditions, the no-observed-adverse-effect level of TBAc is considered to be 800 mg/kg/day for dams and 400 mg/kg/day for embryo-fetal development. 相似文献
80.
Nishikawa K Biewener AA Aerts P Ahn AN Chiel HJ Daley MA Daniel TL Full RJ Hale ME Hedrick TL Lappin AK Nichols TR Quinn RD Satterlie RA Szymik B 《Integrative and comparative biology》2007,47(1):16-54
Neuromechanics seeks to understand how muscles, sense organs,motor pattern generators, and brain interact to produce coordinatedmovement, not only in complex terrain but also when confrontedwith unexpected perturbations. Applications of neuromechanicsinclude ameliorating human health problems (including prosthesisdesign and restoration of movement following brain or spinalcord injury), as well as the design, actuation and control ofmobile robots. In animals, coordinated movement emerges fromthe interplay among descending output from the central nervoussystem, sensory input from body and environment, muscle dynamics,and the emergent dynamics of the whole animal. The inevitablecoupling between neural information processing and the emergentmechanical behavior of animals is a central theme of neuromechanics.Fundamentally, motor control involves a series of transformationsof information, from brain and spinal cord to muscles to body,and back to brain. The control problem revolves around the specifictransfer functions that describe each transformation. The transferfunctions depend on the rules of organization and operationthat determine the dynamic behavior of each subsystem (i.e.,central processing, force generation, emergent dynamics, andsensory processing). In this review, we (1) consider the contributionsof muscles, (2) sensory processing, and (3) central networksto motor control, (4) provide examples to illustrate the interplayamong brain, muscles, sense organs and the environment in thecontrol of movement, and (5) describe advances in both roboticsand neuromechanics that have emerged from application of biologicalprinciples in robotic design. Taken together, these studiesdemonstrate that (1) intrinsic properties of muscle contributeto dynamic stability and control of movement, particularly immediatelyafter perturbations; (2) proprioceptive feedback reinforcesthese intrinsic self-stabilizing properties of muscle; (3) controlsystems must contend with inevitable time delays that can simplifyor complicate control; and (4) like most animals under a varietyof circumstances, some robots use a trial and error processto tune central feedforward control to emergent body dynamics. 相似文献