93 research outputs found
TGF-β mediated FGF10 signaling in cranial neural crest cells controls development of myogenic progenitor cells through tissue–tissue interactions during tongue morphogenesis
AbstractSkeletal muscles are formed from two cell lineages, myogenic and fibroblastic. Mesoderm-derived myogenic progenitors form muscle cells whereas fibroblastic cells give rise to the supportive connective tissue of skeletal muscles, such as the tendons and perimysium. It remains unknown how myogenic and fibroblastic cell–cell interactions affect cell fate determination and the organization of skeletal muscle. In the present study, we investigated the functional significance of cell–cell interactions in regulating skeletal muscle development. Our study shows that cranial neural crest (CNC) cells give rise to the fibroblastic cells of the tongue skeletal muscle in mice. Loss of Tgfbr2 in CNC cells (Wnt1-Cre;Tgfbr2flox/flox) results in microglossia with reduced Scleraxis and Fgf10 expression as well as decreased myogenic cell proliferation, reduced cell number and disorganized tongue muscles. Furthermore, TGF-β2 beads induced the expression of Scleraxis in tongue explant cultures. The addition of FGF10 rescued the muscle cell number in Wnt1-Cre;Tgfbr2flox/flox mice. Thus, TGF-β induced FGF10 signaling has a critical function in regulating tissue–tissue interaction during tongue skeletal muscle development
Fluorescence and chemiluminescence behavior of distyrylbenzene bearing two arms of dipicolylaminomethyl groups: Interactions with zinc ion and ATP
Available online 31 January 2018.The absorption and fluorescence spectral study of the distyrylbenzene bearing two arms of the dipicolylaminomethyl groups, the effective ligands for Zn2+, was studied in the presence of Zn2+ and ATP. Upon complexation of the distyrylbenzene with zinc ions in acetonitrile, enhancement of the fluorescence intensity was observed due to inhibition of intramolecular PET (photo-induced electron transfer) quenching, but no effect was found in aqueous media because the equilibrium laid to the free form of the ligands. In contrast, the addition of ATP disodium salt was effective to enhance the fluorescence intensity of the combination of the distyrylbenzne and Zn2+ in aqueous media. This assembly was applied to the peroxyoxalate chemiluminescence system and a significant increase in the intensity was observed, which provides a potential detection for ATP by chemiluminescence. (C) 2018 Elsevier B.V. All rights reserved.ArticleSPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY. 195:223-229 (2018)journal articl
Clinical Approach to a Suspected Case of First Branchial Arch Syndrome
First branchial arch syndrome is a congenital disorder characterized by a wide spectrum of anomalies in the first branchial arch, mainly affecting the lower jaw, ear, or mouth, during early embryonic development. We sought to confirm a suspected case of this syndrome by making differential diagnosis and taking an intensive clinical approach. A 12-year-6-month-old girl with a horizontally impacted left canine in the maxilla had the history of digital fusion in her hands and feet and has been suffering from hearing impairment of her left ear. To diagnose this case and make her careful treatment plan, we further carried out cephalometric analysis and mutation analysis. Her face looks like asymmetry and is not apparently symmetric by cephalometric analysis. Mutation analysis of the patient was conducted by direct DNA sequencing of the goosecoid gene, which is an excellent candidate for determination of hemifacial microsomia, but no changes in this gene were identified. We could not precisely diagnose this case as first branchial arch syndrome. However, certain observations in this case, including hearing impairment of the left ear, allow us to suspect this syndrome
Chemogenetic activation of endogenous arginine vasopressin exerts anorexigenic effects via central nesfatin-1/NucB2 pathway
Irradiation by a Combination of Different Peak-Wavelength Ultraviolet-Light Emitting Diodes Enhances the Inactivation of Influenza A Viruses
Influenza A viruses (IAVs) pose a serious global threat to humans and their livestock. This study aimed to determine the ideal irradiation by ultraviolet-light emitting diodes (UV-LEDs) for IAV disinfection. We irradiated the IAV H1N1 subtype with 4.8 mJ/cm2 UV using eight UV-LEDs [peak wavelengths (WL) = 365, 310, 300, 290, 280, 270, and 260 nm)] or a mercury low pressure (LP)-UV lamp (Peak WL = 254 nm). Inactivation was evaluated by the infection ratio of Madin–Darby canine kidney (MDCK) cells or chicken embryonated eggs. Irradiation by the 260 nm UV-LED showed the highest inactivation among all treatments. Because the irradiation-induced inactivation effects strongly correlated with damage to viral RNA, we calculated the correlation coefficient (RAE) between the irradiant spectrum and absorption of viral RNA. The RAE scores strongly correlated with the inactivation by the UV-LEDs and LP-UV lamp. To increase the RAE score, we combined three different peak WL UV-LEDs (hybrid UV-LED). The hybrid UV-LED (RAE = 86.3) significantly inactivated both H1N1 and H6N2 subtypes to a greater extent than 260 nm (RAE = 68.6) or 270 nm (RAE = 42.2) UV-LEDs. The RAE score is an important factor for increasing the virucidal effects of UV-LED irradiation
紫外線発光ダイオード照射は宿主細胞内でのウイルスRNAの複製と転写を抑制することでA型インフルエンザウイルスを不活化する
Influenza A viruses (IAVs) pose a serious global threat to humans and their livestock, especially poultry and pigs. This study aimed to investigate how to inactivate IAVs by using different ultraviolet-light-emitting diodes (UV-LEDs). We developed sterilization equipment with light-emitting diodes (LEDs) those peak wavelengths were 365 nm (UVA-LED), 310 nm (UVB-LED), and 280 nm (UVC-LED). These UV-LED irradiations decreased dose fluence-dependent plaque-forming units of IAV H1N1 subtype (A/Puerto Rico/8/1934) infected Madin-Darby canine kidney (MDCK) cells, but the inactivation efficiency of UVA-LED was significantly lower than UVB- and UVC-LED. UV-LED irradiations did not alter hemagglutination titer, but decreased accumulation of intracellular total viral RNA in infected MDCK cells was observed. Additionally, UV-LED irradiations suppressed the accumulation of intracellular mRNA (messenger RNA), vRNA (viral RNA), and cRNA (complementary RNA), as measured by strand-specific RT-PCR. These results suggest that UV-LEDs inhibit host cell replication and transcription of viral RNA. Both UVB- and UVC-LED irradiation decreased focus-forming unit (FFU) of H5N1 subtype (A/Crow/Kyoto/53/2004), a highly pathogenic avian IAV (HPAI), in infected MDCK cells, and the amount of FFU were lower than the H1N1 subtype. From these results, it appears that IAVs may have different sensitivity among the subtypes, and UVB- and UVC-LED may be suitable for HPAI virus inactivation
Protein instability and functional defects caused by mutations of dihydro-orotate dehydrogenase in Miller syndrome patients
Synopsis Miller syndrome is a recessive inherited disorder characterized by postaxial acrofacial dysostosis. It is caused by dysfunction of the DHODH (dihydroorotate dehydrogenase) gene, which encodes a key enzyme in the pyrimidine de novo biosynthesis pathway and is localized at mitochondria intermembrane space. We investigated the consequence of three missense mutations, G202A, R346W and R135C of DHODH, which were previously identified in patients with Miller syndrome. First, we established HeLa cell lines stably expressing DHODH with Miller syndrome-causative mutations: G202A, R346W and R135C. These three mutant proteins retained the proper mitochondrial localization based on immunohistochemistry and mitochondrial subfractionation studies. The G202A, R346W DHODH proteins showed reduced protein stability. On the other hand, the third one R135C, in which the mutation lies at the ubiquinone-binding site, was stable but possessed no enzymatic activity. In conclusion, the G202A and R346W mutation causes deficient protein stability, and the R135C mutation does not affect stability but impairs the substrate-induced enzymatic activity, suggesting that impairment of DHODH activity is linked to the Miller syndrome phenotype
Inhibitory Effects of Antithrombin III on Interactions between Blood Cells and Endothelial Cells during Retinal Ischemia-Reperfusion Injury
PURPOSE. Infiltrating leukocytes have long been widely thought to be key mediators of ischemia-reperfusion injury. Recently, however, evidence suggests that platelets accumulating in postischemic tissues also contribute to ischemia-reperfusion injury because of their inflammatory properties and promotion of formation of thrombi. This study was designed to evaluate quantitatively the inhibitory effects of antithrombin (AT)-III on the interactions between blood cells and retinal endothelial cells in vivo after transient retinal ischemia. METHODS. Transient retinal ischemia was induced for 60 minutes in male Long-Evans rats by ligation of the optic nerve. AT III (250 U/kg) was administered intravenously just after induction of ischemia. Leukocyte and platelet behavior in the retina was evaluated in vivo with a scanning laser ophthalmoscope. Expression of P-selectin and intracellular adhesion molecule (ICAM)-1 in the postischemic retina was investigated by reverse transcription-polymerase chain reaction and immunohistochemistry. After 14 days of reperfusion, ischemia-induced retinal damage was evaluated histologically. RESULTS. Administration of AT III significantly inhibited leukocyte rolling along the major retinal veins and subsequent accumulation of leukocytes in the postischemic retina. Furthermore, the maximum number of rolling and adherent platelets was reduced by 76% (P Ͻ 0.01) and 48% (P Ͻ 0.01), respectively, at 12 hours after reperfusion. Immunohistochemical studies also revealed the suppressive effect of AT III on expression of P-selectin and ICAM-1. Finally, histologic examination demonstrated the protective effects of AT III against retinal damage after transient retinal ischemia. CONCLUSIONS. This study demonstrates the inhibitory effects of AT III on leukocyte and platelet recruitment to the postischemic retina, which may account for the neuroprotective properties of this ␣-2 globulin against retinal ischemia-reperfusion injury. (Invest Ophthalmol Vis Sci. 2003;44:332-341) DOI: 10.1167/iovs.02-0493 I nfiltrating leukocytes have long been acknowledged to be a feature of ischemia-reperfusion injury. 1-4 Recently, however, evidence suggests that platelets also play an important role in the pathogenesis of ischemia-reperfusion injury. 5,6 The importance of platelets is supported by many studies that have demonstrated the beneficial effects of platelet depletion against ischemia-reperfusion injury. 20,21 Thrombin, which is the terminal serine protease of the coagulation cascade, has the ability to activate platelets and fibrinogen. Recently, many investigators have focused on the role of thrombin in various pathologic conditions. It has been demonstrated that an increase in thrombin in postischemic tissues activates vascular endothelial cells. Such activated vascular endothelial cells express adhesion molecules, which contribute to the recruitment of leukocytes and platelets. We recently developed an in vivo method to quantitatively evaluate platelet-endothelium interactions in rat retina. 26 Using this method, we have found that platelets roll along and adhere to retinal venous endothelium during ischemia-reperfusion and that these interactions are mediated by endothelial Pselectin, not by platelet P-selectin. MATERIALS AND METHODS Animal Model Male pigmented Long-Evans rats (200 -250 g) were used in this study. Transient retinal ischemia was induced for 60 minutes in the right eye of each rat
Complete resolution of a calcifying cystic odontogenic tumor with physiological eruption of a dislocated permanent tooth after marsupialization in a child with a mixed dentition: a case report
A novel underuse model shows that inactivity but not ovariectomy determines the deteriorated material properties and geometry of cortical bone in the tibia of adult rats
Our goal in this study was to determine to what extent the physiologic consequences of ovariectomy (OVX) in bones are exacerbated by a lack of daily activity such as walking. We forced 14-week-old female rats to be inactive for 15 weeks with a unique experimental system that prevents standing and walking while allowing other movements. Tibiae, femora, and 4th lumbar vertebrae were analyzed by peripheral quantitative computed tomography (pQCT), microfocused X-ray computed tomography (micro-CT), histology, histomorphometry, Raman spectroscopy, and the three-point bending test. Contrary to our expectation, the exacerbation was very much limited to the cancellous bone parameters. Parameters of femur and tibia cortical bone were affected by the forced inactivity but not by OVX: (1) cross-sectional moment of inertia was significantly smaller in Sham-Inactive rat bones than that of their walking counterparts; (2) the number of sclerostin-positive osteocytes per unit cross-sectional area was larger in Sham-Inactive rat bones than in Sham-Walking rat bones; and (3) material properties such as ultimate stress of inactive rat tibia was lower than that of their walking counterparts. Of note, the additive effect of inactivity and OVX was seen only in a few parameters, such as the cancellous bone mineral density of the lumbar vertebrae and the structural parameters of cancellous bone in the lumbar vertebrae/tibiae. It is concluded that the lack of daily activity is detrimental to the strength and quality of cortical bone in the femur and tibia of rats, while lack of estrogen is not. Our inactive rat model, with the older rats, will aid the study of postmenopausal osteoporosis, the etiology of which may be both hormonal and mechanical
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