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41.
Identification of neural progenitors in the adult mammalian eye 总被引:27,自引:0,他引:27
We have shown that the embryonic mammalian retina contains neural progenitors which display stem cell properties in vitro. Here we report the characterization of neural progenitors isolated from the adult mammalian eye. These quiescent cells, located in the pigmented ciliary bodies, proliferate in the presence of FGF2 and express the neuroectodermal marker nestin. The proliferating cells give rise to neural spheres and are multipotential; they express cell type-specific markers corresponding to neurons and glia. In addition, neural progenitors can generate secondary neural spheres, thus displaying potential to self-renew. The ciliary body-derived neural progenitors display retina-specific properties; the undifferentiated cells express Chx10, a retinal progenitor marker, and upon differentiation express markers corresponding to specific retinal cell types. Therefore, the pigmented ciliary body in the adult mammalian eye harbors neural progenitors that display stem cell properties and have the capacity to give rise to retinal neurons in vitro. 相似文献
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Nguyen Phuong Thao Le Duc Dat Ninh Thi Ngoc Vu Anh Tu Tran Thi Hong Hanh Phan Thi Thanh Huong Nguyen Xuan Nhiem Bui Huu Tai Nguyen Xuan Cuong Nguyen Hoai Nam Pham Van Cuong Seo Young Yang Sohyun Kim Doobyeong Chae Young-Sang Koh Phan Van Kiem Chau Van Minh Young Ho Kim 《Bioorganic & medicinal chemistry letters》2013,23(6):1823-1827
Three new pyrrole oligoglycosides, astebatheriosides A–C (1–3), and a new furan oligoglycoside, astebatherioside D (4), were isolated from the starfish Asterina batheri by various chromatographic methods. Their structures were elucidated by spectroscopic and chemical methods. Compounds 2, 3, and 4 moderately inhibited IL-12 p40 production in lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs) with IC50 values of 36.4, 31.6, and 22.8 μM, respectively. 相似文献
44.
The ectodomain of the human T-cell leukemia virus type 1 TM glycoprotein is involved in postfusion events. 总被引:2,自引:1,他引:2 下载免费PDF全文
To examine the contribution of the transmembrane envelope glycoprotein (TM) to the infectivity of the human T-cell leukemia virus type 1 (HTLV-1), single amino acid substitutions were introduced throughout its ectodomain. The mutated envelopes were tested for intracellular maturation and for functions, including ability to elicit syncytium formation and ability to mediate cell-to-cell transmission of the virus. Three major phenotypes, defining three functionally distinct regions, were identified. (i) Mutations causing defects in intracellular maturation of the envelope precursor are mostly distributed in the central portion of the TM ectodomain, containing the immunosuppressive peptide. This region, which includes vicinal cysteines thought to form an intramolecular disulfide bridge, is probably essential for correct folding of the protein. (ii) Mutations resulting in reduced syncytium-forming ability despite correct intracellular maturation are clustered in the amino-terminal part of the TM ectodomain, within the leucine zipper-like motif. Similar motifs with a propensity to form coiled-coil structures have been implicated in the fusion process driven by other viral envelope proteins, and HTLV-1 may thus conform to this general rule for viral fusion. (iii) Mutants with increased syncytium-forming ability define a region immediately amino-terminal to the membrane-spanning domain. Surprisingly, these mutants exhibited severe defects in infectivity, despite competence for fusion. Existence of this phenotype indicates that capacity for cell-to-cell fusion is not sufficient to ensure viral entry, even in cell-to-cell transmission. The ectodomain of the TM glycoprotein thus may be involved in postfusion events required for full infectivity of HTLV-1, which perhaps represents a unique feature of this poorly infectious retrovirus. 相似文献
45.
Tran Tinh Hien Nguyen Thi Dung Nguyen Thanh Truong Ninh Thi Thanh Van Tran Nguyen Bich Chau Nguyen Van Minh Hoang Tran Thi Thu Nga Cao Thu Thuy Pham Van Minh Nguyen Thi Cam Binh Tran Thi Diem Ha Pham Van Toi To Song Diep James I. Campbell Elaine Stockwell Constance Schultsz Cameron P. Simmons Clare Glover Winnie Lam Filipe Marques James P. May Anthony Upton Ronald Budhram Gordon Dougan Jeremy Farrar Nguyen Van Vinh Chau Christiane Dolecek 《PloS one》2010,5(7)
Background
The emergence of drug resistant typhoid fever is a major public health problem, especially in Asia. An oral single dose typhoid vaccine would have major advantages. M01ZH09 is a live oral single dose candidate typhoid vaccine containing Salmonella enterica serovar Typhi (Ty2 aroC − ssaV −) ZH9 with two independently attenuating deletions. Studies in healthy adults demonstrated immunogenicity and an acceptable safety profile.Objectives
We conducted a randomised placebo controlled, single-blind trial to evaluate the safety and immunogenicity of M01ZH09 in healthy Vietnamese children aged 5 to 14 years.Methods
Subjects were randomly assigned to receive either a nominal dose of 5×109 CFU of M01ZH09 or placebo and were followed up for 28 days. The primary safety outcome was the proportion of subjects with any adverse event attributed to M01ZH09. The primary immunogenicity endpoint was the proportion of subjects who showed a positive immune response to M01ZH09 in the Salmonella Typhi lipopolysaccharide (LPS) specific serum IgA and IgG ELISA.Principal Findings
One hundred and fifty-one children were enrolled, 101 subjects received M01ZH09 and 50 subjects received placebo. An intention to treat analysis was conducted. There were no serious adverse events and no bacteraemias. In the M01ZH09 group, 26 (26%; 95% CI, 18–5%) of 101 subjects experienced adverse events compared to 11 (22%; 95% CI, 12–36%) of 50 subjects in the placebo group (odds ratio (OR) [95%CI] = 1.23 [0.550–2.747]; p = 0.691). Faecal shedding of S. Typhi (Ty2 aroC − ssaV −) ZH9 was detected in 51 (51%; 95% CI, 41–61%) of 100 M01ZH09 subjects. No shedding was detected beyond day 3. A positive immune response, defined as 70% increase (1.7 fold change) in LPS specific serum IgG (day 14 or 28) and/or 50% increase (1.5 fold change) in LPS specific serum IgA (day 7 or 14) from baseline was detected in 98 (97%; 95% CI, 92–99%) of 101 M01ZH09 recipients and 8 (16%; 95% CI, 7–29%) of 50 placebo recipients. Twenty-eight (100%; 95% CI, 88–100%) of 28 vaccine recipients who were evaluated in the LPS specific IgA ELISPOT assay showed a positive response compared to none of the 14 placebo recipients tested.Conclusions
This was the first phase II trial of a novel oral candidate typhoid vaccine in children in an endemic country. M01ZH09 had an appropriate safety profile and was immunogenic in children.Trial Registration
Controlled-trials.comISRCTN91111837 相似文献46.
47.
Leonid Heifets Julie Simon Van Pham 《Annals of clinical microbiology and antimicrobials》2005,4(1):1-7
Background
Eradication of Helicobacter pylori is an important objective in overcoming gastric diseases. Many regimens are currently available but none of them could achieve 100% success in eradication. Eugenol and cinnamaldehyde that are commonly used in various food preparations are known to possess antimicrobial activity against a wide spectrum of bacteria.Aim
The present study was performed to assess the in vitro effects of eugenol and cinnamaldehyde against indigenous and standard H. pylori strains, their minimum inhibitory concentrations (MICs) and time course lethal effects at various pH.Methods
A total of 31 strains (29 indigenous and one standard strain of H. pylori ATCC 26695, one strain of E. coli NCIM 2089) were screened. Agar dilution method was used for the determination of drug sensitivity patterns of isolates to the commonly used antibiotics and broth dilution method for the test compounds.Results
Eugenol and cinnamaldehyde inhibited the growth of all the 30 H. pylori strains tested, at a concentration of 2 μg/ml, in the 9th and 12th hours of incubation respectively. At acidic pH, increased activity was observed for both the compounds. Furthermore, the organism did not develop any resistance towards these compounds even after 10 passages grown at sub-inhibitory concentrations.Conclusion
These results indicate that the two bioactive compounds we tested may prevent H. pylori growth in vitro, without acquiring any resistance. 相似文献48.
Bai Songling Tuan Pham Anh Tatsuki Miho Yaegaki Hideaki Ohmiya Akemi Yamamizo Chihiro Moriguchi Takaya 《Plant Molecular Biology Reporter》2016,34(1):257-264
Plant Molecular Biology Reporter - Transgenic approach is an excellent way for the clarification of gene function, but it is generally difficult to create transgenic plants for most of the fruit... 相似文献
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Nguyen M Doan V Pham T Nguyen V Nguyen B Oishi T Tokura H 《Journal of human ergology》2003,32(2):107-110
Thermally comfortable zones in Vietnamese were investigated during winter in Hanoi. The subjects were 21 males (age: 19.7 +/- 0.4 yrs; height: 165 +/- 1.5 cm; body mass: 55.1 +/- 1.1 kg) and 19 females (age: 19.7 +/- 0.4 yrs; height; 155.6 +/- 1.7 cm; body mass: 45.6 +/- 1.3 kg). Each participant entered singly the climatic chamber controlled at 22 degrees C and 40% RH. After 20 min rest, the participant was requested to indicate on a 7-point scale (Table 1) how he or she felt to the room temperature given. Then, the room temperature increased by 1 degrees C over 10 min every 20 min. Just before the rise of the room temperature, the participant judged his or her thermal sensation. More than 90% of the participants felt 24-29 degrees C of the room temperature as "slightly cool", "neutral" and "slightly warm" (Table 2). We defined these sensations as "thermally comfort". These thermally comfortable zones were quite higher than those (20-24 degrees C) recommended by ISO-7730 (1994). We discussed these discrepancies in terms of higher establishment of thermoregulatory set-point in the Vietnamese. 相似文献