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41.
de Pontual L Népote V Attié-Bitach T Al Halabiah H Trang H Elghouzzi V Levacher B Benihoud K Augé J Faure C Laudier B Vekemans M Munnich A Perricaudet M Guillemot F Gaultier C Lyonnet S Simonneau M Amiel J 《Human molecular genetics》2003,12(23):3173-3180
Congenital central hypoventilation syndrome (CCHS, Ondine's curse) is a rare disorder of the chemical control of breathing. It is frequently associated with a broad spectrum of dysautonomic symptoms, suggesting the involvement of genes widely expressed in the autonomic nervous system. In particular, the HASH-1-PHOX2A-PHOX2B developmental cascade was proposed as a candidate pathway because it controls the development of neurons with a definitive or transient noradrenergic phenotype, upstream from the RET receptor tyrosine kinase and tyrosine hydroxylase. We recently showed that PHOX2B is the major CCHS locus, whose mutation accounts for 60% of cases. We also studied the proneural HASH-1 gene and identified a heterozygous nucleotide substitution in three CCHS patients. To analyze the functional consequences of HASH-1 mutations, we developed an in vitro model of noradrenergic differentiation in neuronal progenitors derived from the mouse vagal neural crest, reproducing in vitro the HASH-PHOX-RET pathway. All HASH-1 mutant alleles impaired noradrenergic neuronal development, when overexpressed from adenoviral constructs. Thus, HASH-1 mutations may contribute to the CCHS phenotype in rare cases, consistent with the view that the abnormal chemical control of breathing observed in CCHS patients is due to the impairment of noradrenergic neurons during early steps of brainstem development. 相似文献
42.
Park HD Lee WK Ooya T Park KD Kim YH Yui N 《Journal of biomedical materials research. Part A》2003,66(3):596-604
Sulfonated polyrotaxanes (PRx-SO(3)'s), in which sulfonated alpha-cyclodextrins (alpha-CDs) were threaded onto the poly(ethylene glycol) (PEG) segments in a PEG-b-poly(propylene glycol) (PPG)-b-PEG triblock copolymer (Pluronic) capped with benzyloxycarbonyl (Z)-L-phenylalanine (Z-L-Phe), were prepared as a novel surface-modifying biomaterial. Surface modification of the polyurethane (PU) was carried out by blending the PRx-SO(3)'s with a PU solution, followed by solution casting. The incorporated PRx-SO(3)'s led to the enhanced hydrophilicity by changing the surface properties of the PU matrix. Modified PUs showed the stable entrapment of the PRx-SO(3)'s with little extraction into water and enhanced mechanical properties after exposure to water compared to the PU control. The incorporated PRx-SO(3)'s repelled the proteins and kept them from closely approaching the surface areas, prevented platelet activation by thrombin, and effectively repelled bacteria. These results suggest that both the supramolecular structure of the polyrotaxanes and exposure of the sulfonated groups onto the surfaces contribute to these phenomena. Thus, surface modification with PRx-SO(3)'s is suggested to be useful for the fabrication of biocompatible medical devices. 相似文献
43.
Bong Hyo Lee Rong Jie Zhao Jin Young Moon Seong Shoon Yoon Jung-Ae Kim Heeduk An Young Kyu Kwon Meeyul Hwang Seong Hun Choi Insop Shim Bong Hyun Kim Chae Ha Yang 《Neuroscience letters》2008
In our previous study we demonstrated that acupuncture at Shenmen (HT7) points suppressed a decrease of accumbal dopamine (DA) release in ethanol-withdrawn rats. Furthermore, here we found that it inhibited behavioral withdrawal signs of ethanol. In an effort to better understand the mechanisms underlying this inhibition, the potential role of GABA receptor system in acupuncture was investigated. Male Sprague–Dawley rats were treated with 3 g/kg/day of ethanol (20%, w/v) or saline by intraperitoneal injection for 21 days. Following 48 or 72 h of ethanol withdrawal, acupuncture was applied at bilateral HT7 for 1 min. The selective GABAA antagonist bicuculline and the selective GABAB antagonist SCH 50911 were injected intraperitoneally 20 min before acupuncture, respectively. Importantly, suppressive effects of acupuncture on DA deficiency were completely abolished by SCH 50911, but not by bicuculline, whereas ameliorating effects of acupuncture on ethanol withdrawal syndrome were completely blocked either by SCH 50911 or bicuculline. These results suggest that acupuncture at specific acupoint HT7 may normalize the DA release in the mesolimbic system and attenuate withdrawal syndrome through the GABAB receptor system in ethanol-withdrawn rats. 相似文献
44.
Joon Young Song Seok Hoon Ha Sae Yoon Kee Hye Won Jeong Hee Jin Cheong Woo Joo Kim 《Journal of clinical virology》2007,38(2):149-152
BACKGROUND: Influenza vaccination is the primary method for preventing influenza and its severe complications. Healthcare workers (HCWs) are one of the priority groups for the influenza vaccination. OBJECTIVES: To determine whether healthy HCWs, who were vaccinated with the same subtype for the two previous years, could be given less priority for influenza immunization under the vaccine shortage. STUDY DESIGN: We measured hemagglutination-inhibition antibody titers from sequential serum samples in 50 pre-immune subjects and 50 age-matched vaccine-naive subjects: immediately prior to the administration of the vaccine, 4-6 weeks, and 6 months after the vaccination. RESULTS: Prevaccination titers were maintained above protective level and high protection rates were observed for all three strains in pre-immune subjects: A/H1N1, A/H3N2, and B strains. As for the sequential changes, the protection rates for all three strains still remained above 70% until 6 months following the vaccination. CONCLUSION: Skipping influenza vaccination for a year could be considered in healthy pre-immune HCWs under the epidemic of the same subtype as two previous years. 相似文献
45.
Infection of mice with Mycobacterium lepraemurium caused significant functional alterations of the mononuclear phagocyte system. Accelerated clearance of sheep red blood cells was consistently demonstrated throughout the infection and the infected mice showed progressive anaemia. Infected mice showed an enhanced ability to limit growth of phagocytosed Listeria monocytogenes in spleens during the early stages of infection, whereas moribund leprous mice lost this ability. Autoradiography showed that uninfected Kupffer cells and splenic macrophages of moribund mice could still phagocytose Listeria, suggesting that MLM infection did not affect the capacity of Listeria to localize to macrophages but interfered in some way with subsequent killing of such bacteria. The possible mechanisms underlying these observations are discussed. 相似文献
46.
Jo EK Kumaki S Wei D Tsuchiya S Kanegane H Song CH Noh HY Kim YO Kim SY Chung HY Kim YH Kook H 《Journal of Korean medical science》2004,19(1):123-126
X-linked severe combined immunodeficiency (X-SCID) is a rare, life-threatening immune disorder, caused by mutations in the gamma c chain gene, which encodes an essential component of the cytokine receptors for interleukin-2 (IL-2), IL-4, IL-7, IL-9, IL-15, and IL-21. A 13-month-old boy with recurrent infections who had reduced serum immunoglobulin levels and decreased numbers of CD3, CD16/56 cells was evaluated for gamma c chain gene mutation and protein expression. The patient had a C-to-T point mutation at nucleotide position 690, one of the hot spots, resulting in a single amino acid substitution of cysteine for arginine (R226C), as determined by direct sequencing and PCR-RFLP. The patient's mother was a heterozygous carrier. Percutaneous umbilical cord blood sampling was performed at the 6-month of gestation in a subsequent pregnancy. As the immunophenotype of the fetus showed an identical pattern, the pregnancy was terminated and genetic analysis of the abortus confirmed recurrence. This is the first report of the molecular diagnosis of X-SCID in Korea. Genetic analysis of the gamma c chain gene is useful for definite diagnosis and genetic counseling for X-SCID. 相似文献
47.
IL-15 is a potent T cell chemoattractant, and this cytokine and its unique α subunits, IL-15Rα, can modify immune cell expression of several T cell chemokines and their receptors. Facial nerve axotomy in mice leads to T cell migration across an intact blood–brain-barrier (BBB), and under certain conditions T cells can provide neuroprotection to injured neurons in the facial motor nucleus (FMN). Although chemokines and chemoattractant cytokines are thought to be responsible for T cell migration to the injured cell bodies, data addressing this question are lacking. This study tested the hypothesis that T cell homing to the axotomized FMN would be impaired in knockout (KO) mice with the IL-15 and IL-15Rα genes deleted, and sought to determine if microglial responsiveness and motoneuron death are affected. Both IL-15KO and IL-15RαKO mice exhibited a marked reduction in CD3+ T cells and had fewer MHC2+ activated microglia in the injured FMN than their respective WT controls at day 14 post-axotomy. Although there was a relative absence of T cell recruitment into the axotomized FMN in both knockout strains, IL-15RαKO mice had five times more motoneuron death (characterized by perineuronal microglial clusters engulfing dead motoneurons) than their WT controls, whereas dead neurons in IL-15KO did not differ from their WT controls. Further studies are needed to dissect the mechanisms that underlie these observations (e.g., central vs. peripheral immune contributions). 相似文献
48.
de Jong MD Bach VC Phan TQ Vo MH Tran TT Nguyen BH Beld M Le TP Truong HK Nguyen VV Tran TH Do QH Farrar J 《The New England journal of medicine》2005,352(7):686-691
In southern Vietnam, a four-year-old boy presented with severe diarrhea, followed by seizures, coma, and death. The cerebrospinal fluid contained 1 white cell per cubic millimeter, normal glucose levels, and increased levels of protein (0.81 g per liter). The diagnosis of avian influenza A (H5N1) was established by isolation of the virus from cerebrospinal fluid, fecal, throat, and serum specimens. The patient's nine-year-old sister had died from a similar syndrome two weeks earlier. In both siblings, the clinical diagnosis was acute encephalitis. Neither patient had respiratory symptoms at presentation. These cases suggest that the spectrum of influenza H5N1 is wider than previously thought. 相似文献
49.
Soo Hyun Kim Yang-Kyoo Han Young Ha Kim Sung Ill Hong 《Macromolecular chemistry and physics.》1992,193(7):1623-1631
L -Lactide was polymerized with stannous 2-ethylhexanoate (stannous octoate) in the presence of pentaerythritol to investigate multifunctional initiation. The prepared oligomers contain starshaped 4-arm molecules when the mole ratio of [lactide]/[pentaerythritol] is above 32. The molecular weight of oligomers coincides with the [lactide]/[pentaerythritol] ratio, indicating that pentaerythritol in conjugation with stannous octoate is an initiator for the “living” polymerization of L-lactide. 相似文献
50.
Ok-Sub Lee Byung-Jo Ha Soo-Nam Park Yoon-Sik Lee 《Macromolecular chemistry and physics.》1997,198(9):2971-2976
Chitosan/calcium-alginate beads were prepared by a coacervation method in aqueous medium. Their swelling properties and morphologies were studied. Complexed beads with a mean diameter of 500 μm were obtained by dropwise addition of a sodium alginate solution into a chitosan-calcium chloride solution. From scanning electron microscopic studies, we observed that chitosan modifies the morphology of calcium-alginate beads. The swelling properties of chitosan/calcium-alginate beads are different from those of calcium-alginate beads. In the case of the calcium-alginate beads, the swelling volume increases as the pH of the medium increases. However, chitosan/calcium-alginate beads show a maximum swelling volume at pH 9.0. 相似文献