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1.
Plasmonics - A polarization-independent gas sensor based on crescent plasmonic dipole antenna loaded with graphene monolayer is introduced in this paper for environment...  相似文献   

2.
Saleh N  Fathalla SI  Nabil R  Mosaad AA 《Anaerobe》2011,17(6):426-430
The present study was conducted to evaluate the efficacy and safety of three vaccination regimes of Clostridium perfringens (C. perfringens) type A, C and combined A&C toxoids based on their clinical signs and immunological effects. The vaccines were administered two times at two weeks interval (7 & 21 days old), then the birds were challenged (35 days old) with virulent strains of C. perfringens type A, C and combined A&C. Blood samples were taken one week after the first and second vaccination as well as after challenge. The evaluated parameters in this study included: clinical signs, gross intestinal lesions, complete blood count (CBC), serum protein, liver profiles, and enzyme-linked immunosorbent assay (ELISA) test for detecting serum antibody titers. The results revealed that immunization of broilers with C. perfringens type A, C and combined A&C toxoids resulted in a significant decrease in numbers of chickens with intestinal lesions particularly with the A&C toxoids vaccine. Results of the CBC values were significantly increased in all treated groups and challenged groups. Total leukocytic count decreased in challenged non vaccinated group while increased in challenged vaccinated birds. Results of biochemical assays implicated that there were a significant increase in serum protein and liver profiles. ELISA results explored a significant increase in antibody titers after immunization of broilers with C. perfringens type A, C and combined A&C toxoids particularly after the second dose of vaccination. We concluded that immunization of broilers with toxoid vaccines particularly the combined type A & C is safe, well-tolerated and can protect broiler chickens against necrotic enteritis particularly after the second booster dose of the vaccine.  相似文献   

3.
He  Ziying  Peng  Yisheng  Guan  Dongsheng  Hu  Zhan  Chen  Yujuan  Lee  Shing Yip 《Plant and Soil》2018,429(1-2):425-436
Plant and Soil - A dominant species of steppe in northern China, Stipa grandis, is gradually being replaced by S. krylovii due to climate change events. The aim of this study was...  相似文献   

4.
Yin  Z.  Zhang  X.  Li  J.  Jiao  Y.  Kong  Q.  Mu  Y. 《Russian Journal of Genetics》2019,55(12):1488-1498
Russian Journal of Genetics - Genomic imprinting is an epigenetic mechanism that leads to parent-specific gene expression. A number of imprinted genes have been identified in humans and...  相似文献   

5.
A retrospective ecological study of paediatric asthma patients who attended the Accident and Emergency (A&E) department of the Paediatric Priority Care Facility at the Eric Williams Medical Sciences Complex in relation to Saharan dust visibility and other climatic variables for the period 23 May 2001 to 13 May 2002 was undertaken to determine if there is an association between paediatric A&E asthma visits and Saharan dust cloud cover. A Poisson regression model was used to determine the statistical relationship between acute paediatric asthma A&E visits and Saharan dust cover with and without other variables such as climatic parameters and month. During the study period, there were 2,655 A&E visits for acute asthma. There was an association between increased paediatric asthma admissions and increased Saharan dust cover. The best fitting model estimated that in one month, such as June, a deterioration of visibility due to increased Saharan dust cover from no dust (visibility =16 km) to very dusty (visibility =7 km) would increase a daily admission rate of 7.8 patients to 9.25 when climate variables such as barometric pressure and humidity were kept constant.  相似文献   

6.
Amyloid β-peptide (Aβ) is hypothesized to play a key role by oxidatively impairing the capacity of red blood cells (RBCs) to deliver oxygen to the brain. These processes are implicated in the pathogenesis of Alzheimer''s disease (AD). Although plasma Aβ has been investigated thoroughly, the presence and distribution of Aβ in human RBCs are still unclear. In this study, we quantitated Aβ40 and Aβ42 in human RBCs with ELISA assays, and provided evidence that significant amounts of Aβ could be detected in RBCs and that the RBC Aβ levels increased with aging. The RBC Aβ levels increased with aging. On the other hand, providing an antioxidant supplement (astaxanthin, a polar carotenoid) to humans was found to decrease RBC Aβ as well as oxidative stress marker levels. These results suggest that plasma Aβ40 and Aβ42 bind to RBCs (possibly with aging), implying a pathogenic role of RBC Aβ. Moreover, the data indicate that RBC Aβ40 and Aβ42 may constitute biomarkers of AD. As a preventive strategy, therapeutic application of astaxanthin as an Aβ-lowering agent in RBCs could be considered as a possible anti-dementia agent.

Trial Registration

Controlled-Trials.com ISRCTN42483402  相似文献   

7.
Doklady Biochemistry and Biophysics - The  effect  of  adrenaline  in  various  concentrations  and  dopamine  at...  相似文献   

8.
The expression patterns of three microtubule-associated proteins (MAP1A, MAP1B, and MAP2A&B) were investigated in the developing optic tectum. Expression of MAP1B and middle-molecular-weight peptide of neurofilament (NF-M) was first observed in the same mesencephalic cells on day 3 of incubation, indicating that neuroblasts had been produced. At day 5, MAP1A and MAP2A&B expression appeared in the cellular layer containing the first neuroblasts that differentiate into large multipolar cells. The NF-M+ neurites in the striatum album centrale (SAC) and the striatum opticum (SO) were MAP1B+ up to day 19, but the intensity of MAP1B immunoreactivity decreased with development. All three MAPs were expressed in large multipolar neurons in the developing stratum griseum centrale from the beginning of maturation. Stratum griseum et fibrosum centrale cellular layers, containing radially arranged piriform neurons, were MAP1A/MAP2A&B on day 11 but became MAP1A+/MAP2A&B+ during later stages. These results suggest that the timing of MAP expression in neuronal maturation of large multipolar cells differs from that of piriform cells. The expression of MAPs has revealed specific cellular events in the developing optic tectum. Based on our observations, the development of the optic tectum can be divided into four periods.  相似文献   

9.
The production and aggregation of amyloid β peptides (Aβ) has been linked to the development and progression of Alzheimer's disease. It is apparent that the various structural forms of Aβ can affect cell signalling pathways and the activity of neurons differently. In this study, we investigated the effects of oligomeric and fibrillar aggregates of Aβ 1–42 (Aβ42) and non-aggregated peptide upon activation of the ERK/MAPK signalling pathway. In SH-SY5Y cells, acute exposure to oligomeric Aβ42 led to phosphorylation of ERK1/2 at concentrations as low as 1 nM and up to 100 nM. These changes were detected as early as 5 min following exposure to 100 nM oligomeric Aβ42, reaching a maximum level after 10 min. Phosphorylation of ERK1/2 subsequently declined to and remained at basal levels after 30 min to 2 h of exposure. Fibrillar aggregates of Aβ42 did not significantly induce phosphorylation of ERK1/2 and non-aggregated Aβ42 did not activate the pathway. The effects of oligomeric Aβ42 to increase ERK phosphorylation above basal levels were inhibited by MLA, a specific antagonist of the α7 nAChR. U0126, an inhibitor of MEK, the upstream activator of ERK1/2, completely blocked induction of ERK1/2 phosphorylation. Oligomeric aggregates of Aβ42 are the principal structural form of the peptide that activates ERK/MAPK in SH-SY5Y cells and these effects are mediated by the α7 nAChR.  相似文献   

10.
Regarding mutations of PROP1 (Prophet of POU1F1) gene significantly associating with combined pituitary hormone deficiency (CPHD) in human patients and animals, PROP1 gene is a novel important candidate gene for detecting genetic variation and growth, reproduction, metabolism traits selection and breeding. The aim of this study was to detect PROP1 gene mutation of the exon 1–3 and its association with wool traits in 345 Chinese Merino sheep. In this study, on the basis of PCR-SSCP and DNA sequencing methods, ten novel SNPs within the sheep PROP1 gene, namely, AY533708: g.45A > G resulting in Glu15Glu, g.1198A > G, g.1341G > C resulting in Arg63Ser, g.1389G > A resulting in Ala79Ala, g.1402C > T resulting in Leu84Leu, g.1424A > G resulting in Asn91Ser, g.1522C > T, g.1556A > T, g.1574T > C, g.2430C > G were reported. In addition, association analysis showed that three genotypes of P4 fragment were significantly associated with fiber diameter in the analyzed population (P = 0.044). These results strongly suggested that polymorphisms of the PROP1 gene could be a useful molecular marker for sheep breeding and genetics through marker-assisted selection (MAS).  相似文献   

11.
Journal of Ichthyology - Three species of the genus Tribolodon (T. hakonensis, T. brandtii, and T. sachalinensis) and hybrids between T. hakonensis and...  相似文献   

12.
Base substitution is one of the raw fuels that produce genetic variation and drive evolution. Recent studies have shown that the genome components affect mutation patterns to some extent. In order to infer the correlation between the Transition/Transversion ratio (Ts/Tv) and the number of immediately adjacent A&T nucleotides, we investigated 3611007 Oryza sativa SNPs (including 45462 coding SNPs, and 242811 intronic SNPs) and 32019 Arabidopsis SNPs. The results show that Ts/Tv is negatively correlated with the number of immediately adjacent A&T in O. Sativa and Arabidopsis. We further calculated AT2 (the number of SNPs whose immediately adjacent nucleotides are either A or T) and AT0 (the number of SNPs whose immediately adjacent nucleotides are either C or G) for all 6 types of SNPs. C/G SNP of O. sativa and Arabidopsis has the highest AT2/AT0, which denotes C/G SNP may be influenced by the adjacent A&T nucleotides mostly. For SNPs in O. sativa, the neighboring effect of A&T nucleotides is limited to 2 nucleotides on both sides; for SNPs in Arabidopsis, the effect extends no more than 4 nucleotides on both sides.  相似文献   

13.
14.
Base substitution, the most common mutation thatone or more bases substitute another, is the main causethat creates individual variation, community diversityand the evolution of species. Studying the role andmechanism of base substitution could help peopl…  相似文献   

15.

Objective

To assess the safety, tolerability, pharmacokinetics, and pharmacodynamics of the Fc-inactivated anti-β amyloid (Aβ) monoclonal antibody (mAb) GSK933776 in patients with mild Alzheimer’s disease (AD) or mild cognitive impairment (MCI).

Methods

This was a two-part, single blind, placebo-controlled, first-time-in-human (FTIH) study of single (n = 18) and repeat dose (n = 32) intravenous GSK933776 0.001–6 mg/kg (ClinicalTrials.gov: NCT00459550). Additional safety data from an open-label, uncontrolled, single dose study of intravenous GSK933776 1–6 mg/kg (n = 18) are included (ClinicalTrials.gov: NCT01424436).

Results

There were no cases of amyloid-related imaging abnormalities-edema (ARIA-E) or –hemorrhage (ARIA-H) after GSK933776 administration in both studies. Three patients across the two studies developed anti-GSK933776 antibodies. Plasma GSK933776 half-life (t1/2) was 10–15 days after repeat dosing. After each of three administrations of GSK933776, plasma levels of total Aβ42 and Aβ increased whereas plasma levels of free Aβ decreased dose dependently; no changes were observed for placebo. For total Aβ42 the peak:trough ratio was ≤2 at doses ≥3 mg/kg; for total Aβ the ratio was ≤2 at 6 mg/kg. CSF concentrations of Aβ showed increases from baseline to week 12 for Aβ X–38 (week 12:baseline ratio: 1.65; 95%CI: 1.38, 1.93) and Aβ X–42 (week 12:baseline ratio: 1.18; 95%CI: 1.06, 1.30) for values pooled across doses.

Conclusion

In this FTIH study the Fc-inactivated anti-Aβ mAb GSK933776 engaged its target in plasma and CSF without causing brain ARIA-E/H in patients with mild AD or MCI.

Trial Registration

ClinicalTrials.gov NCT00459550  相似文献   

16.
17.
Chronic cerebral hypoperfusion (CCH) increases the risk of Alzheimer disease (AD) through several biologically plausible pathways, but the relationship between CCH and the development of AD remains uncertain. To investigate expression of APP, BACE1 and Aβ in the hippocampus of BCCAO rats and study pathophysiological mechanism of AD from CCH. CCH rat model was established by chronic bilateral common carotid artery occlusion (BCCAO). Behavior was evaluated after BCCAO with Morris water maze and open-field task. Expression of Aβ was measured by enzyme linked immunosorbent assay (ELISA). β-Amyloid precursor protein cleavage enzyme 1 (BACE1) and β-amyloid precursor protein (APP) were tested by ELISA, Western blotting and RT-PCR. Cognitive impairment occurred with CCH by Morris water maze test and open-field task. The BACE1 and Aβ level in BCCAO rats was more increased than sham-operation control rats (P < 0.01) but APP had no difference(P > 0.05). The expression of BACE1 and Aβ has no inter-grouop difference in BCCAO rats (P > 0.05). The level of BACE1 and Aβ had positive correlation with cognitive impairment (P < 0.01) while no correlation was observed between APP and cognitive impairment. Chronic cerebral ischemia contributes to cognitive impairment and vascular pathogenesis of Alzheimer’s disease that chronic cerebral hypoperfusion increases BACE1 and Aβ level in brain.  相似文献   

18.

Background  

Self-assembly of the amyloid-β peptide (Aβ) has been implicated in the pathogenesis of Alzheimer's disease (AD). As a result, synthetic molecules capable of inhibiting Aβ self-assembly could serve as therapeutic agents and endogenous molecules that modulate Aβ self-assembly may influence disease progression. However, increasing evidence implicating a principal pathogenic role for small soluble Aβ aggregates warns that inhibition at intermediate stages of Aβ self-assembly may prove detrimental. Here, we explore the inhibition of Aβ1–40 self-assembly by serum albumin, the most abundant plasma protein, and the influence of this inhibition on Aβ1–40 activation of endothelial cells for monocyte adhesion.  相似文献   

19.
To study the role of different DNA repair genes in the resistance of Deinococcus radiodurans to mono- and polychromatic UV radiation, wild-type strain and knockout mutants in RecA, PprA, and IrrE of D. radiodurans were irradiated with UV-C (254 nm), UV-(A + B) (280–400 nm) and UV-A (315–400 nm) radiation, and survival was monitored. The strain deficient in recA was highly sensitive to UV-C radiation compared to the wild-type, but showed no loss of resistance against irradiation with UV-(A + B) and UV-A, while pprA and irrE-deficient strains exhibited elevated sensitivity to UV-A and UV-(A + B) radiation. These results suggest that the repair of DNA double-strand breaks is essential after treatment with highly energetic UV-C radiation, whereas protection from oxidative stress may play a greater role in resistance to environmentally relevant UV radiation.  相似文献   

20.
β-Amyloid peptide (Aβ) 1–42, involved in the pathogenesis of Alzheimer’s disease, binds copper ions to form Aβ · Cun complexes that are able to generate H2O2 in the presence of a reductant and O2. The production of H2O2 can be stopped with chelators. More reactive than H2O2 itself, hydroxyl radicals HO (generated when a reduced redox active metal complex interacts with H2O2) are also probably involved in the oxidative stress that creates brain damage during the disease. We report in the present work a method to monitor the effect of chelating agents on the production of hydrogen peroxide by metallo-amyloid peptides. The addition of H2O2 associated to a pre-incubation step between ascorbate and Aβ · Cun allows to study the formation of H2O2 but also, at the same time, its transformation by the copper complexes. Aβ · Cun peptides produce but do not efficiently degrade H2O2. The reported analytic method, associated to precipitation experiments of copper-containing amyloid peptides, allows to study the inhibition of H2O2 production by chelators. The action of a ligand such as EDTA is probably due to the removal of the copper ions from Aβ · Cun, whereas bidentate ligands such as 8-hydroxyquinolines probably act via the formation of ternary complexes with Aβ · Cun. The redox activity of these bidentate ligands can be modulated by the incorporation or the modification of substituents on the quinoline heterocycle.  相似文献   

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