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161.
This study was conducted to assess effects of harvest date (i.e., 40 and 60 d after planting) and N fertilization rate (i.e., 120, 180, 240 kg N/ha) on the nutritive value of amaranth forage (Amaranthus hypochondriacus) using a factorial experiment with a randomized complete block design. The content of dry matter (DM), crude protein (CP), true protein (TP), ether extract (EE), water soluble carbohydrates (WSC), ash-free neutral detergent fiber (NDFom), ash-free acid detergent fiber (ADFom), lignin(sa), ash, Ca, P, Na, K, oxalic acid and nitrate were determined. Soluble CP (SP) and protein fractions non-protein N (A), true protein rapidly degraded in the rumen (B1), true protein degraded in the rumen at a moderate rate (B2), true protein associated with the cell wall and slowly degraded in the rumen (B3) and acid detergent insoluble CP (C) were measured according to the Cornell Net Carbohydrate and Protein System. In vitro gas production (IVGP), OM disappearance (OMD) and NDFom disappearance (NDFD) were determined using a gas production technique. Results showed that the later harvest date increased (P<0.05) DM, EE, WSC, NDFom, ADFom, lignin(sa), B3 and C; while CP, TP, ash, Ca, P, K, SP, A, B1, B2, nitrate, total and soluble oxalic acid, IVGP, b (i.e., gas production from the insoluble fermentable fractions at 120 h), c (i.e., rate of gas production during incubation), OMD and NDFD decreased (P<0.05). With increasing N fertilization rate, CP, TP, EE, P, nitrate, oxalic acid, SP, A, b, OMD and NDFD increased (P<0.05), however B2 declined (P<0.05). Increasing N fertilization increased yield, CP concentration and nutrient digestibility. At 40 d after planting use of amaranth forage as a ruminant feed is limited due to its high nitrate content. However, at 60 d, although a depression in digestibility and CP content occurred, this forage has the potential as a ruminant feed due to the much lower nitrate levels.  相似文献   
162.
To determine the plasma lipid and lipoprotein profiles and their possible association with the type of β-thalassemia mutation we studied 103 major β-thalassemia patients including 71 children and 32 young adults compared to 102 healthy subjects consisted of 90 children and 12 young healthy adults. The plasma lipid and lipoprotein levels were measured by conventional methods. Considering all of the patients the levels of total cholesterol (TC), LDL-cholesterol (LDL-C), and HDL-cholesterol (HDL-C) were significantly lower compared to controls. However, the level of TG was significantly higher in cases than controls. Comparing thalassemic patients homozygous for a β0 type of mutation with those homozygous for a β+ type of mutation (IVSI.110 G:A) indicated that the levels of LDL-C, TC were significantly increased and TG concentration tended to be higher in the latter patients. In conclusion, our study indicates that hemolytic stress results in hypocholesterolemia in major β-thalassemia patients and the presence of more severe genotype in patients is correlated with more reduction in TG, TC, and LDL-C levels.  相似文献   
163.
164.
Psoriasis is a chronic inflammatory skin disease with an unknown aetiology that has been associated with abnormal plasma lipid metabolism and oxidative stress. There are controversial results in the previous studies investigating oxidant/antioxidant systems in psoriasis. The aim of this work was to evaluate the plasma levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), total bilirubin (T. Bili), direct bilirubin (D. Bili), uric acid (UA), apolipoproteins (ApoA1 and ApoB), Lp(a) and activities of paraxonase 1 (PON1) in 100 patients with psoriasis and 100 controls, and to look for a correlation between these parameters in psoriasis. PON1, bilirubin and UA were measured spectrophotometrically, MDA by the high‐performance liquid chromatography method, apolipoproteins and Lp(a) by immunoprecipitation assays, and lipid and other biochemical parameters were determined by routine laboratory methods. In patients with psoriasis, there was a significant decrease in PON1, SOD and CAT activities (P < 0.05) and an increase in MDA levels (P < 0.01). Also, the levels of bilirubin (total and direct) and UA were decreased in patients with psoriasis but were not significant (P > 0.05). These results suggest that psoriasis was in a state of oxidative stress and that the protective effects of high‐density lipoprotein against atherosclerosis may be dependent on PON1 activity. Moreover, there is a negative correlation between antioxidant with Lp(a), apoB and MDA levels, suggesting that subjects with higher levels of Lp(a) and apoB and lower levels of antioxidant are more exposed to oxidative damage. These findings may explain in part the reported increase in cardiovascular mortality in psoriasis. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
165.
Nonenveloped virus must penetrate the cellular membrane to access the cytoplasm without the benefit of membrane fusion. For birnavirus, one of the peptides present in the virus capsid, pep46 for infectious bursal disease virus, is able to induce pores into membranes as an intermediate step of the birnavirus-penetration pathway. Using osmotic protection experiments, we demonstrate here that pep46 and its pore-forming N-terminal moiety (pep22) form pores of different diameters, 5–8 and 2–4 nm, respectively, showing that both pep46 moieties participate to pore formation. The solution structures of pep46, pep22, and pep24 (the pep46 C-terminal moiety) in different hydrophobic environments and micelles determined by 1H NMR studies provide structural insights of the pep46 domain interaction. In CDCl3/CD3OH mixture and in dodecylphosphocholine micelles, the N-terminal domain of pep46 is structured in a long kinked helix, although the C terminus is structured in one or two helices depending upon the solvents used. We also show that the folding and the proline isomerization status of pep46 depend on the type of hydrophobic environment. NMR spectroscopy with labeled phospholipid micelles, differential scanning calorimetry, and plasmon waveguide resonance studies show the peptides lie parallel to the lipid-water interface, perturbing the fatty acid chain packing. All these data lead to a model in which the two domains of pep46 interact with the membrane to form pores.  相似文献   
166.
Babaei  F.  Javidnasab  M.  Rezaei  A. 《Plasmonics (Norwell, Mass.)》2018,13(4):1491-1497
Plasmonics - In this work, we proposed new shape nanoparticles in the name of supershape nanoparticles by manipulation in the morphology of a disk nanoparticle. The electric field distribution of...  相似文献   
167.
Abstract

Datura innoxia (D. innoxia) has an extensive usage in traditional medicine and can also be used for intervention therapy in order to treat cancer. Despite of accomplishing some researches on D. innoxia mechanism, still our knowledge is very little about exact D. innoxia apoptotic mechanism on human chronic myeloid leukemia cells (K562 cells). This study purpose was to clarify the molecular mechanism of apoptosis, which was mediated by D. innoxia leaves aqueous extract in K562 cells. MTT assay and flow cytometry was applied in order to assess the viability and apoptosis induction of K562 cells and normal human lymphoid B cells in the D. innoxia presence. Finally, the expression of the apoptotic related genes (p53, BAX, BCL2, Caspases 3, 6, 7 and 9) were evaluated using quantitative Real-Time PCR. Western blot analysis was applied for assessing the protein expression. MTT results indicated that D. innoxia could inhibit the viability of K562 cells in a dose- and time-dependent manner. In parallel, D. innoxia inhibitory effect on normal human lymphoid B cells was lower in comparison with its effect on K562 cells at the same concentrations and same incubation time. Apoptosis induction in K562 cells after D. innoxia exposure was determined by flow cytometry. Apoptosis was activated by D. innoxia in K562 cells throughout increasing the expression of P53, BAX/BCL2 ratio, caspase 9, 3, 6, 7. Western blot analysis demonstrated significant increase in cleaved PARP-1 and cleaved caspase 3 in treated K562 cells with high D. innoxia leaves aqueous extract concentration. D. innoxia leaves trigger apoptosis in K562 cells throughout intrinsic apoptotic pathway.

Communicated by Ramaswamy H. Sarma  相似文献   
168.
Abstract

The genus Verbascum L. (Scrophulariaceae) includes medicinal plants, which have several bioactive compounds especially saponins. The possible recovery ability of Verbascum sinuatum from drought stress conditions was assessed by using salicylic acid (SA), methyl jasmonate (MJA) and titanium dioxide nanoparticles (TiO2NPs) as plant growth regulators (PGRs) in liquid culture media. Thirty days-old plants were exposed to different concentrations of polyethylene glycol (PEG-6000) for creating artificial drought conditions (0, ?0.3, and ?0.6?MPa osmotic potential) and also treated with 200?µM methyl jasmonate (MJA), 100?µM salicylic acid (SA) and 20?ppm TiO2 nanoparticles (TiO2NPs). Results showed that the growth parameters and the content of photosynthetic pigments decreased at higher drought level (?0.6?MPa). However, SA and TiO2NPs alleviated the adverse effects of drought stress by increasing water stress tolerance through promotion of enzymatic and nonenzymatic antioxidant defense systems. MJA negatively affected the growth parameters and increased the content of malondialdehyde (MDA), hydrogen peroxide (H2O2) and total saponin and also the activity of peroxidase (POD) and polyphenol oxidase (PPO). Based on the results obtained from this study, the recovery treatments mainly affected the defense-related metabolism in Verbasum sinuatum plants.  相似文献   
169.
A parametric study was conducted to delineate the efficacy of personal protective equipment (PPE), such as ballistic faceshields and advanced combat helmets, in the case of a blast. The propagations of blast waves and their interactions with an unprotected head, a helmeted one, and a fully protected finite element head model (FEHM) were modeled. The biomechanical parameters of the brain were recorded when the FEHM was exposed to shockwaves from the front, back, top, and bottom. The directional dependent tissue response of the brain and the variable efficiency of PPE with respect to the blast orientation were two major results of this study.  相似文献   
170.
BACKGROUND: Several genes coding for different cytokines may affect host susceptibility to tuberculosis. METHODS: In the present study, the allele and genotype frequencies of a number polymorphic genes coding for cytokines or cytokine receptors were investigated in Iranian patients with pulmonary tuberculosis (PTB). RESULTS: From the IL-1 cluster, a positive, significant difference was found at position -889, where the T/T genotype was over represented in PTB patients (p = 0.01); a positive, significant increase was found in the IL1R PstI 1970 C/C genotype, where the C allele was over represented in the PTB patients (p = 0.01). A significant negative association at codon 10 TGF-beta, T allele, was shown in our patients and the C allele and C/C genotype were over represented in the PTB patients (P<0.005). For TNF-alpha at position -238, we found a negative association for the G/A genotype and a positive association for the G/G genotype (p = 0.0009). Significant negative associations at position -590 IL-4, T allele and the T/T genotype were shown in our patients (p = 0.0007); also, the C allele and T/C genotype were significantly increased in our patients (P<0.05). With IL-6 at -174, G/G increased and G/C decreased significantly in the patients (P<0.005). CONCLUSION: Pro-inflammatory cytokines such as TNF-alpha and TGF-beta seem to be decreased, and IL-6 increased in PTB patients.  相似文献   
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