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121.
Constance Schultsz Nguyen Van Dung Le Thanh Hai Do Quang Ha J. S. Malik Peiris Wilina Lim Jean-Michel Garcia Nguyen Dac Tho Nguyen Thi Hoang Lan Huynh Huu Tho Phan Xuan Thao H. Rogier van Doorn Nguyen Van Vinh Chau Jeremy Farrar Menno D. de Jong 《PloS one》2009,4(11)
Background
Between 2003 and 2005, highly pathogenic avian influenza A (H5N1) viruses caused large scale outbreaks in poultry in the Ho Chi Minh City area in Vietnam. We studied the prevalence of antibodies against H5N1 in poultry workers and cullers who were active in the program in Ho Chi Minh City in 2004 and 2005.Methodology/Principal Findings
Single sera from 500 poultry workers and poultry cullers exposed to infected birds were tested for antibodies to avian influenza H5N1, using microneutralization assays and hemagglutination inhibition assay with horse blood. All sera tested negative using microneutralization tests. Three samples showed a 1∶80 titer in the hemagglutination inhibition assay.Conclusions/Significance
This study provides additional support for the low transmissibility of clade 1 H5N1 to humans, but limited transmission to highly exposed persons cannot be excluded given the presence of low antibody titers in some individuals. 相似文献122.
Duong P. Huynh Marwan Maalouf Alcino J. Silva Felix E. Schweizer Stefan M. Pulst 《PloS one》2009,4(7)
Mouse models with physiological and behavioral differences attributable to differential plasticity of hippocampal and amygdalar neuronal networks are rare. We previously generated ataxin-2 (Atxn2) knockout mice and demonstrated that these animals lacked obvious anatomical abnormalities of the CNS, but showed marked obesity and reduced fertility. We now report on behavioral changes as a consequence of Atxn2-deficiency. Atxn2-deficiency was associated with impaired long-term potentiation (LTP) in the amygdala, but normal LTP in the hippocampus. Intact hippocampal plasticity was associated behaviorally with normal Morris Water maze testing. Impaired amygdala plasticity was associated with reduced cued and contextual fear conditioning. Conditioned taste aversion, however, was normal. In addition, knockout mice showed decreased innate fear in several tests and motor hyperactivity in open cage testing. Our results suggest that Atxn2-deficiency results in a specific set of behavioral and cellular disturbances that include motor hyperactivity and abnormal fear-related behaviors, but intact hippocampal function. This animal model may be useful for the study of anxiety disorders and should encourage studies of anxiety in patients with spinocerebellar ataxia type 2 (SCA2). 相似文献
123.
124.
Tran Cong Toai Huynh Duy Thao Nguyen Phuong Thao Ciro Gargiulo Phan Kim Ngoc Pham Hung Van D. Michael Strong 《Cell and tissue banking》2010,11(3):269-280
It is well accepted that human umbilical cord blood (UCB) is a source of mesenchymal stem cells (MSCs) which are able to differentiate
into different cell phenotypes such as osteoblasts, chondrocytes, adipocytes, myocytes, cardiomyocytes and neurons. The aim
of this study was to isolate MSCs from human UCB to determine their osteogenic potential by using different kinds of osteogenic
medium. Eventually, only those MSCs cultured in osteogenic media enriched with vitamin D2 and FGF9, were positive for osteocalcin by RT-PCR. All these cells were positive for alizarin red, alkaline phosphatase and
Von Kossa. The results obtained from RT-PCR have confirmed that osteogenesis is complete by expression of the osteocalcin
marker. In conclusion, vitamin D2, at least in vitro, may replace vitamin D3 as an osteogenic stimulator factor for MSC differentiation. 相似文献
125.
Vanessa Lagal Emily M. Binder My‐Hang Huynh Bjorn F. C. Kafsack Philippa K. Harris Roberto Diez Dawn Chen Robert N. Cole Vern B. Carruthers Kami Kim 《Cellular microbiology》2010,12(12):1792-1808
Host cell invasion by Toxoplasma gondii is critically dependent upon adhesive proteins secreted from the micronemes. Proteolytic trimming of microneme contents occurs rapidly after their secretion onto the parasite surface and is proposed to regulate adhesive complex activation to enhance binding to host cell receptors. However, the proteases responsible and their exact function are still unknown. In this report, we show that T. gondii tachyzoites lacking the microneme subtilisin protease TgSUB1 have a profound defect in surface processing of secreted microneme proteins. Notably parasites lack protease activity responsible for proteolytic trimming of MIC2, MIC4 and M2AP after release onto the parasite surface. Although complementation with full‐length TgSUB1 restores processing, complementation of Δsub1 parasites with TgSUB1 lacking the GPI anchor (Δsub1::ΔGPISUB1) only partially restores microneme protein processing. Loss of TgSUB1 decreases cell attachment and in vitro gliding efficiency leading to lower initial rates of invasion. Δsub1 and Δsub1::ΔGPISUB1 parasites are also less virulent in mice. Thus TgSUB1 is involved in micronemal protein processing and regulation of adhesive properties of macromolecular adhesive complexes involved in host cell invasion. 相似文献
126.
127.
Huynh KT Baker DW Harris R Church J Brauner CJ 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2011,181(7):883-892
Fish exposed to elevated water CO2 experience a rapid increase in blood CO2 levels (hypercapnia), resulting in acidification of both intra- and extra-cellular compartments. While the mechanisms associated
with extracellular pH regulation have been well explored, much less is known about intracellular pH (pHi) regulation. There is great interest in developing non-animal models for research. One such model is the rainbow trout hepatoma
cell line (RTH 149), which has been used to study a wide range of topics; however, no studies have investigated its potential
use in pHi regulation. Employing the pH-sensitive fluoroprobe BCECF, the present study examined pHi regulation in RTH 149 under normocapnia and during extracellular acidification induced by either elevated CO2 or 1 M HCl. During exposure to hypercapnia, RTH 149 cells were acidified without recovery as long as the elevated CO2 was maintained. In addition, rates of pHi recovery from NH4Cl-induced acidosis were significantly lower in cells exposed to hypercapnia or HCl compared to that in normocapnic cells,
indicating that elevated CO2 indirectly impeded pHi recovery through a reduction in pHe and/or pHi. Moreover, pHi regulation in RTH 149 was EIPA-sensitive, suggesting that an NHE may be involved. Overall, RTH 149 may have the potential
for identifying transporters likely to play a role in pHi regulation in fish. However, it should not be used as a complete replacement for in vivo studies, especially to quantify acid–base regulatory ability at whole animal level, since RTH 149 appeared to have enhanced
pHi recovery rates relative to primary hepatocytes. 相似文献
128.
129.
Agnieszka A. Kendrick Michael J. Holliday Nancy G. Isern Fengli Zhang Carlo Camilloni Chi Huynh Michele Vendruscolo Geoffrey Armstrong Elan Z. Eisenmesser 《Protein science : a publication of the Protein Society》2014,23(4):464-480
Interleukin‐8 (CXCL8, IL‐8) is a proinflammatory chemokine important for the regulation of inflammatory and immune responses via its interaction with G‐protein coupled receptors, including CXC receptor 1 (CXCR1). CXCL8 exists as both a monomer and as a dimer at physiological concentrations, yet the molecular basis of CXCL8 interaction with its receptor as well as the importance of CXCL8 dimer formation remain poorly characterized. Although several biological studies have indicated that both the CXCL8 monomer and dimer are active, biophysical studies have reported conflicting results regarding the binding of CXCL8 to CXCR1. To clarify this problem, we expressed and purified a peptide (hCXCR1pep) corresponding to the N‐terminal region of human CXCR1 (hCXCR1) and utilized nuclear magnetic resonance (NMR) spectroscopy to interrogate the binding of wild‐type CXCL8 and a previously reported mutant (CXCL8M) that stabilizes the monomeric form. Our data reveal that the CXCL8 monomer engages hCXCR1pep with a slightly higher affinity than the CXCL8 dimer, but that the CXCL8 dimer does not dissociate upon binding hCXCR1pep. These investigations also showed that CXCL8 is dynamic on multiple timescales, which may help explain the versatility in this interleukin for engaging its target receptors. 相似文献
130.
Marieke?Pingen Ramin?Sarrami-Forooshani Annemarie?MJ?Wensing Petra?van Ham Agata?Drewniak Charles?AB?Boucher Teunis?BH?GeijtenbeekEmail author Monique?NijhuisEmail author 《Retrovirology》2014,11(1):113