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991.
Vectors with restriction site banks. IV. pJRD184, a 3793-bp plasmid vector with 49 unique restriction sites 总被引:16,自引:0,他引:16
An improved restriction site bank vector has been constructed from plasmid pJRD158. The new version is smaller and contains 43 unique restriction sites. It should greatly facilitate cloning versatility by providing unique sites for most commercially available restriction enzymes. 相似文献
992.
Adenylate cyclase. A new kinetic analysis of the effects of hormones and fluoride ion 总被引:7,自引:0,他引:7
C de Ha?n 《The Journal of biological chemistry》1974,249(9):2756-2762
993.
J A Kim S Ha K Y Shin S Kim K J Lee Y H Chong K-A Chang Y-H Suh 《Cell death & disease》2015,6(6):e1789
Alzheimer''s disease (AD) is characterized by neuronal loss in several regions of the brain. Recent studies have suggested that stem cell transplantation could serve as a potential therapeutic strategy to halt or ameliorate the inexorable disease progression. However, the optimal stage of the disease for stem cell transplantation to have a therapeutic effect has yet to be determined. Here, we demonstrated that transplantation of neural stem cells into 12-month-old Tg2576 brains markedly improved both cognitive impairments and neuropathological features by reducing β-amyloid processing and upregulating clearance of β-amyloid, secretion of anti-inflammatory cytokines, endogenous neurogenesis, as well as synapse formation. In contrast, the stem cell transplantation did not recover cognitive dysfunction and β-amyloid neuropathology in Tg2576 mice aged 15 months when the memory loss is manifest. Overall, this study underscores that stem cell therapy at optimal time frame is crucial to obtain maximal therapeutic effects that can restore functional deficits or stop the progression of AD.Alzheimer''s disease (AD) is the most common neurodegenerative disorder, and is characterized by progressive cognitive dysfunction and memory loss that are caused by the death of nerve cells in several brain regions, including the cortex and hippocampus. Pathologically, senile plaques, including amyloid beta (Aβ) and carboxy-terminal fragments (CTFs) are derived via amyloid precursor protein (APP) proteolysis, and neurofibrillary tangles, including hyperphosphorylated tau, are two representative hallmarks of AD.1, 2, 3 Together with the accumulation of Aβ, local inflammation, altered hippocampal neurogenesis and synaptic loss have been correlated with cognitive deficits in AD patients.4, 5 However, no treatment has yet been developed that can cure or prevent the progression of dementia.Accumulating evidence indicates that the transplantation of neural stem cells (NSCs) or bone marrow stem cells (BMSCs) into the hippocampus improves cognitive functions in AD animal models.6, 7, 8, 9, 10, 11, 12 The stem cell-induced functional recovery seems to be mediated by either neurotrophic factors and/or neuroprotective cytokines. For instance, genetically engineered stem cells that secrete nerve growth factor (NGF),11, 12 the co-administration of stem cells with brain-derived neurotrophic factor (BDNF) or grafting encapsulated vascular endothelial growth factor (VEGF) secreting cells substantially improved behavioral outcomes of AD animal models.9, 13 Thus, the functional effects of stem cell grafts involve the increase of several neurotrophic factors, such as BDNF, FGF2, insulin-like growth factor 1 (IGF1), NGF and VEGF.10, 14, 15 In contrast, BMSCs or adipose-derived stem cells (ASCs) transplantation induces microglial activation16, 17, 18 and the secretion of neuroprotective cytokines, leading to a decline of Aβ deposits and the restoration of memory deficits in AD mice.18, 19 However, the optimal stage of the disease for stem cell transplantation in AD models has yet to be determined.In this study, we have investigated whether the transplantation of NSCs at two distinguished stages in the disease development could have different beneficial effects in AD model mice, Tg2576 mice.20 In this model, the over-production of Aβ begins at 6–7 months of age, and neuritic plaques with amyloid cores are formed from 9 to 12 months after birth followed by the onset of memory deficits at 12 months of age.21, 22, 23 NSCs were bilaterally transplanted into the dentate gyrus (DG) of the hippocampus and the third ventricle of 12-month-old (early stage) or 15-month-old (advanced stage) Tg2576 and age-matched wild-type (WT) mice. We determined whether the engrafted NSCs at two stages of the disease rescued cognitive deficits and the neuropathology of the mice. 相似文献
994.
Patrick Nadol Siobhan O’connor Hao Duong Linh-Vi N. Le Pham Hong Thang Tran Hong Tram Hoang Thi Thanh Ha Michelle S. Mcconnell Jeff Partridge John Kaldor Matthew Law Tuan Anh Nguyen 《PloS one》2015,10(2)
IntroductionGiven the overlapping modes of transmission of HIV, hepatitis B virus (HBV), and hepatitis C virus (HCV), understanding the burden and relationship of these infections is critical for an effective response. Representative data on these infections among males who inject drugs (MWID), the key high-risk population for HIV in Vietnam, are currently lacking.MethodsData and stored specimens from Vietnam’s 2009-2010 Integrated Biologic and Behavioral Survey, a cross-sectional study among high-risk populations, were used for this analysis. Plasma samples were tested for HIV, HBV, and HCV using commercial assays. A questionnaire was administered to provide demographic, behavior, and service-uptake information. Provincial-level analyses were conducted to profile MWID enrollees and to provide estimates on the prevalence of HIV, HBV, and HCV infection.ResultsAmong 3010 MWID sampled across 10 provinces, the median (range) HIV prevalence was 28.1% (1.0%-55.5%). Median prevalence for current HBV infection (HBsAg+) was 14.1% (11.7%-28.0%), for previous exposure to HBV (total anti-HBc+) was 71.4% (49.9%-83.1%), and for current or past HCV infection (HCV Ag/Ab+) was 53.8% (10.9%-80.8%). In adjusted analysis, HBsAg+ (aOR: 2.09, 1.01-4.34) and HCV Ag/Ab+ (aOR: 19.58, 13.07-29.33) status were significantly associated with HIV infection; the association with total anti-HBc+ approached significance (aOR: 1.29, 0.99-1.68).ConclusionThe prevalence and association between HIV, HBV, and HCV are high among MWID in Vietnam. These findings indicate the need for integrated policies and practice that for the surveillance, prevention, screening, and treatment of both HIV and viral hepatitis among MWID in Vietnam. 相似文献
995.
Byung Il Yoon Kyung-Do Han Kyu Won Lee Hyuk Sang Kwon Sun Wook Kim Dong Wan Sohn Yong-Hyun Cho U-Syn Ha 《PloS one》2015,10(11)
Objective
To investigate the association between insulin resistance (IR) and urinary incontinence in Korean adult women by analyzing the data from the Korea National Health and Nutrition Examination Survey IV (KNHANES) 2007–2009Methods
A nationally representative sample of 5318 non-diabetic Korean women ≥19-years-of-age (3043 premenopausal and 2275 postmenopausal women) was included from KNHANES 2008–2010. IR was measured using the homeostasis model assessment of IR (HOMA-IR). Participants in the highest and lowest quartile of HOMA-IR were defined as insulin-resistant and insulin-sensitive respectively. Women who have current physician-diagnosed urinary incontinence were classified as having urinary incontinence.Results
Incontinence was found in 9.18% of the total population, 8.51% of the premenopausal population, and 10.86% of the postmenopausal population. The prevalence of incontinence increased with age, reaching a peak at 60-69-years-of-age. The prevalence of urinary incontinence increased significantly with higher HOMA-IR quartiles in pre- and post-menopausal women (p for linear association = 0.0458 and 0.0009 respectively). Among post-menopausal women, those in the highest quartile of HOMA-IR were significantly more likely to have urinary incontinence compared to those in the lowest quartile [adjusted odds ratio, 1.72; 95% confidence interval, 1.07–2.77]. However premenopausal population exhibited no association between incontinence and HOMA-IR quartilesConclusion
Our results suggest that the prevalence of incontinence increased across HOMA-IR in non-diabetic adult women, and especially, IR might be a risk factor for incontinence in postmenopausal non-diabetic women. 相似文献996.
Suhyun Kim Yun-Il Lee Ki-Young Chang Dong-Won Lee Sung Chun Cho Young Wan Ha Ji Eun Na Im Joo Rhyu Sang Chul Park Hae-Chul Park 《Molecules and cells》2015,38(11):1013-1021
Most of the axons in the vertebrate nervous system are surrounded by a lipid-rich membrane called myelin, which promotes rapid conduction of nerve impulses and protects the axon from being damaged. Multiple sclerosis (MS) is a chronic demyelinating disease of the CNS characterized by infiltration of immune cells and progressive damage to myelin and axons. One potential way to treat MS is to enhance the endogenous remyelination process, but at present there are no available treatments to promote remyelination in patients with demyelinating diseases.Sulfasalazine is an anti-inflammatory and immune-modulating drug that is used in rheumatology and inflammatory bowel disease. Its anti-inflammatory and immunomodulatory properties prompted us to test the ability of sulfasalazine to promote remyelination. In this study, we found that sulfasalazine promotes remyelination in the CNS of a transgenic zebrafish model of NTR/MTZ-induced demyelination. We also found that sulfasalazine treatment reduced the number of macrophages/microglia in the CNS of demyelinated zebrafish larvae, suggesting that the acceleration of remyelination is mediated by the immunomodulatory function of sulfasalazine. Our data suggest that temporal modulation of the immune response by sulfasalazine can be used to overcome MS by enhancing myelin repair and remyelination in the CNS. 相似文献
997.
The effects of pH and surfactants on the absorption and fluorescence properties of ochratoxin A and zearalenone 下载免费PDF全文
The pH and surfactant dependencies of the absorption and fluorescence properties of ochratoxin A (OTA) and zearalenone (ZEN), the main mycotoxins found as contaminants in foods and feeds, were evaluated. Three surfactants with different ionic properties were investigated, namely sodium dodecyl sulfate (SDS, anionic), Tween 20 (nonionic) and hexadecyltrimethylammonium bromide (CTAB, cationic). The results show that the effects of pH on the absorption wavelength maxima and fluorescence efficiencies of the mycotoxins, which are a consequence of the presence of acidic phenol and/or carboxyl containing fluorophores, are dependent on the ionic nature of the added surfactants. Specifically, the fluorescence responses to pH changes of OTA and ZEN are similar in the presence or absence of Tween 20 and SDS. By contrast, the pH‐dependent fluorescence properties of these mycotoxins are altered when CTAB is present in the solutions. Moreover, unlike OTA, ZEN in aqueous solution displays almost no fluorescence. However, fluorescence enhancement takes place when surfactants are present in aqueous solutions of this mycotoxin. The results of this study demonstrate that the different microenvironments, present in the organized micellar systems created by the individual surfactants, can be potentially employed to modulate the sensitivities and selectivities of the fluorescence detection of OTA or ZEN. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
998.
999.
Hyun-Kyung Lee Ha Eun Song Haeng-Byung Lee Cheol-Soo Kim Mamoru Koketsu Luong Thi My Ngan Young-Joon Ahn 《PloS one》2014,9(4)
Helicobacter pylori is associated with various diseases of the upper gastrointestinal tract, such as gastric inflammation and duodenal and gastric ulcers. The aim of the study was to assess anti-H. pylori effects of the sesquiterpene lactone dehydrocostus lactone (DCL) from Magnolia sieboldii leaves, compared to commercial pure DCL, two previously known sesquiterpene lactones (costunolide and parthenolide), (–)-epigallocatechin gallate, and four antibiotics. The antibacterial activity of natural DCL toward antibiotic-susceptible H. pylori ATCC 700392 and H. pylori ATCC 700824 strains (MIC, 4.9 and 4.4 mg/L) was similar to that of commercial DCL and was more effective than costunolide, parthenolide, and EGCG. The activity of DCL was slightly lower than that of metronidazole (MIC, 1.10 and 1.07 mg/L). The antibacterial activity of DCL was virtually identical toward susceptible and resistant strains, even though resistance to amoxicillin (MIC, 11.1 mg/L for PED 503G strain), clarithromycin (49.8 mg/L for PED 3582GA strain), metronidazole (21.6 mg/L for H. pylori ATCC 43504 strain; 71.1 mg/L for 221 strain), or tetracycline (14.2 mg/L for B strain) was observed. This finding indicates that DCL and the antibiotics do not share a common mode of action. The bactericidal activity of DCL toward H. pylori ATCC 43504 was not affected by pH values examined (4.0–7.0). DCL caused considerable conversion to coccoid form (94 versus 49% at 8 and 4 mg/L of DCL for 48 h). The Western blot analysis revealed that urease subunits (UreA and UreB) of H. pylori ATCC 43504 were not affected by 10 mM of DCL, whereas UreA monomer band completely disappeared at 0.1 mM of (–)-epigallocatechin gallate. Global efforts to reduce the level of antibiotics justify further studies on M. sieboldii leaf-derived materials containing DCL as potential antibacterial products or a lead molecule for the prevention or eradication of drug-resistant H. pylori. 相似文献
1000.
Sarah Hanieh Tran T. Ha Julie A. Simpson Gerard J. Casey Nguyen C. Khuong Dang D. Thoang Tran T. Thuy Sant-Rayn Pasricha Thach D. Tran Tran Tuan Terence Dwyer Jane Fisher Beverley-Ann Biggs 《PLoS medicine》2013,10(6)