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51.
In this work, we proposed a novel aqueous biphasic system (ABS) composed of polypropylene glycol P400 (PPG P400) and hydrophilic ionic liquids (IL), 1-alkyl-3-methylimidazolium bromide (alkyl = ethyl or butyl), forming an upper polymer-rich phase and a lower IL-rich phase at ambient temperature. This new ABS can present interesting characteristics shared by ILs and polymers such as low volatility, good solvation ability, tunable physical properties, and high design capacity for achieving task-specific phase components to enhance the partitioning of target species. Ternary phase diagram of the novel ABS formed by PPG 400 and [C(2) mim]Br in water was measured at T = 298.15 K. Factors affecting the binodal curves such as the cation side alkyl chain length and the temperature were also evaluated. The results were successfully interpreted in terms of the kosmotropic/chaotropic nature of ILs. Furthermore, the phase behavior of the PPG-[C(2) mim]Br ABS is described by the NRTL model. Finally, the extraction potential of the proposed ABS was evaluated through its application to the extraction of the essential amino acids such as L-tryptophan and L-tyrosine. The partition coefficients here obtained demonstrated the fine potential of the proposed ABS for biomolecules separation.  相似文献   
52.
One of the major obstacles in the design of an effective vaccine against HIV-1 is its antigenic variation, which results in viral escape from the immune system. Through a bioinformatics approach, we developed an innovative multivalent HIV-1 vaccine comprised of a pool of 176 lipidated and nonlipidated peptides representing variable regions of Env and Gag proteins. The potency and breadth of the candidate vaccine against a panel of HIV-1 subtypes was evaluated in nonhuman primate (cynomolgus macaques) and humanized mouse (HLA-A2.1) models. The results demonstrate strong immunogenicity with both breadth (humoral and cellular immunity) and depth (immune recognition of widely divergent viral sequences) against heterologous HIV-1 subtypes A-F.  相似文献   
53.
Biomechanics and Modeling in Mechanobiology - Targeted drug delivery (TDD) to abdominal aortic aneurysm (AAA) using a controlled and efficient approach has recently been a significant challenge. In...  相似文献   
54.
To date, there has been little agreement on supporting the hypothesis that how some key vegetative traits of camelina (Camelina sativa (L.) Crantz var. ‘Soheil’) are dependent on plant biomass. Therefore, the main aim of this investigation was to quantify the relationship between the size of camelina plants and seed production across a broad-range of plant densities through modelling approaches. To make a wide range of plant densities, a fan design was used in eight replicates in an experimental field at Sari Agricultural Sciences and Natural Resources University, Iran. To quantify the relation between plant density and other plant traits, a regression analysis was carried out and the coefficient of determination (R2) was considered to evaluate the goodness of fit model. A power model (y = axb) could describe well the relationship between plant density (ranged 113–2905 plants m−2) and plant biomass, seed production, number of seeds per plant, stem diameter, and siliques number, with the coefficient of determination (R2) values of 0.85, 0.87, 0.65, 0.64, and 0.90, respectively. The harvest indexes were 13.8%–26.9%, depending on plant density. Seed production per plant was positively correlated to the siliques number (r = 0.85), the branch number (r = 0.80), and the seed number (r = 0.99) which could be key components of camelina seed production per plant. Furthermore, no significant correlation was found among plant height, thousand-seed weight, and harvest index with seed production per plant. In conclusion, plant biomass could be considered an important trait to predict plant growth models of camelina. Also, a lower plant density of camelina can be compensated by a greater number of siliques, branches and seeds per plant.  相似文献   
55.
The development of an effective vaccine against tuberculosis (Tb) represents one of the major medical challenges of this century. Mycobacterium bovis Bacille Calmette-Guerin (BCG), the only vaccine available at present, is mostly effective at preventing disseminated Tb in children, but shows variable protection against pulmonary Tb, the most common form in adults. The reasons for this poor efficacy are not completely understood, but there is evidence that T regulatory cells (Tregs) might be involved. Similarly, Tregs have been associated with the immunosuppression observed in patients infected with Tb and are therefore believed to play a role in pathogen persistence. Thus, Treg depletion has been postulated as a novel strategy to potentiate M. bovis BCG vaccination on one side, while on the other, employed as a therapeutic approach during chronic Tb infection. Yet since Tregs are critically involved in controlling autoimmune inflammation, elimination of Tregs may therefore also incur the danger of an excessive inflammatory immune response. Thus, understanding the dynamics and function of Tregs during mycobacterial infection is crucial to evaluate the potential of Treg depletion as a medical option. To address this, we depleted Tregs after infection with M. bovis BCG or Mycobacterium tuberculosis (Mtb) using DEREG mice, which express the diphtheria toxin (DT) receptor under the control of the FoxP3 locus, thereby allowing the selective depletion of FoxP3+ Tregs. Our results show that after depletion, the Treg niche is rapidly refilled by a population of DT-insensitive Tregs (diTregs) and bacterial load remains unchanged. On the contrary, impaired rebound of Tregs in DEREG × FoxP3GFP mice improves pathogen burden, but is accompanied by detrimental autoimmune inflammation. Therefore, our study provides the proof-of-principle that, although a high degree of Treg depletion may contribute to the control of mycobacterial infection, it carries the risk of autoimmunity.  相似文献   
56.

Introduction

Cinnamon exerts insulin-enhancing activity in vitro and was demonstrated to improve blood glucose and lipid profiles in several human studies. Such effects may have an impact on metabolically stressed cows.

Objective

To study the effects of cinnamon supplementation during the transition from late pregnancy to early lactation on the metabolism in dairy cows.

Methods

Twenty-four Holstein cows (n?=?8/group) were assigned to either the control group (CTR; without supplementation) or the supplementation groups [supplemental cinnamon at 20 (LCIN) or 40 (HCIN) g/cow per day (d)] from 28 d before calving until 21 d thereafter. Blood samples were assayed for glucose, nonesterified fatty acids (NEFA), β-hydroxybutyrate (BHBA), and insulin; an index estimating insulin sensitivity (RQUICKI) was calculated. The serum metabolome was characterized in the samples collected from d 14 using a non-targeted approach.

Results

The serum concentrations of glucose and insulin did not differ among groups and followed a similar pattern over time. The serum NEFA concentrations were greater in LCIN (d 2, 7, and 14) and HCIN (d 14) than in CTR. On d 14 and 21, LCIN and HCIN had greater serum BHBA concentrations than CTR cows. The top 10 metabolites identified with significantly higher levels in the supplemented than the CTR cows were related to fatty acid metabolism.

Conclusion

The data suggest lipolytic and ketogenic effects of cinnamon supplementation in dairy cows during the transition from late gestation to early lactation. The fatty acid metabolites found elevated in the supplemented cows point towards impaired mitochondrial fatty acid β-oxidation.
  相似文献   
57.
This study evaluated several secondary metabolites, essential oils (EOs) compositions, and antioxidant activity in four medicinal plants that originated in Isfahan rangelands. The species were Astragalus verus, Astragalus adscendens, Daphne mucronata, and Phlomis olivieri. Thirty-two genotypes of these species were evaluated for different biochemical traits. Based on the evaluation of EOs compounds, GC/MS analysis revealed the total number of identified compounds. These compounds were 25, 22, 12, and 22 for A. adscendens, A. verus, D. mucronata, and P. olivieri, respectively. The dominant compounds were phthalate (59.88 %) in A. adscendens, phytol (38.02 %) in A. verus, hexanoic acid (32.05 %) in D. mucronata and β-cubebene (30.94 %) in P. olivieri. Phytochemical analysis showed that D. mucronata, A. adscendens, and P. olivieri had the highest total phenolics content (TPC) (18.24 mg gallic acid equivalent/g dry weight), total flavonoids content (5.57 mg QE/g DW), and total anthocyanins content (0.23 mg/g DW), respectively. The highest total chlorophyll (0.27 mg/g DW), total carotenoids (0.03 mg/g DW), and antioxidant activity (71.36 %) were observed in A. adscendens, A. adscendens and A. verus, respectively. Among all genotypes, the highest TPC (20.1 mg GAE/g DW) was observed in genotype 5 of D. mucronata. This study provided new information on the chemical compounds within the distribution range of these ecologically dominant rangeland species in Isfahan province, Iran. The data revealed that superior genotypes from these species are rich in natural antioxidants and bioactive compounds. Thus, they can be used in ethno pharmacological fields, food, and industrial applications.  相似文献   
58.
Biological Trace Element Research - A systematic review, meta-analysis, and non-carcinogenic risk considering fluoride content of drinking water resources of 31 provinces of Iran among some...  相似文献   
59.
The taxonomy of the Lesser/Asian Short-toed Lark Alaudala rufescenscheleensis complex has been debated for decades, mainly because of minor morphological differentiation among the taxa within the complex, and different interpretations of the geographical pattern of morphological characters among different authors. In addition, there have been few studies based on non-morphological traits. It has recently been suggested based on a molecular study of the lark family Alaudidae that the Sand Lark A. raytal is nested within this complex. We here analysed mitochondrial cytochrome b (cyt b) from 130 individuals across the range of this complex (hereafter called Alaudala rufescens–raytal complex), representing all except two of the 18 currently recognized subspecies. We also analysed 11 nuclear markers from a subsample of these individuals, representing all of the clades found in the cyt b tree. Five primary clades were recovered, which confirmed that A. raytal is nested within this complex. Divergence time estimates among these five clades ranged from 1.76 to 3.16 million years (my; 95% highest posterior density [HPD] 1.0–4.51 my) or 1.99–2.53 my (95% HPD 0.96–4.3 my) in different analyses. Only four of the currently recognized subspecies were recovered as monophyletic in the cyt b tree. Our results call for a taxonomic revision, and we tentatively suggest that at least four species should be recognized, although we stress the need for an approach integrating molecular, morphological and other data that are not yet available.  相似文献   
60.
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