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91.

Background

Individuals with lower socioeconomic status experience higher rates of mortality and are more likely to suffer from numerous diseases. While some studies indicate that humans who suffer from social inequality suffer generally worse health, to our knowledge no controlled experiments of this nature have been done in any species. Lipofuscin is a highly oxidized cross-linked aggregate consisting of oxidized protein and lipid clusters. This eminent terminal oxidation outcome accumulates within cells during aging process.

Methodology/Principal Findings

Thirty two rabbits were assigned into four groups randomly of eight each. The first group encountered food deprivation for eight weeks and was kept in an isolated situation. The second group was food deprived for eight weeks but encountered to other groups continuously. The third group suffered two weeks of deprivation and then received free access to food. The fourth group had free access to diet without any deprivation. All hearts were removed for histopathological evaluation. Cross-sections of hearts were examined by light microscopy for the presence of yellow-brown Lpofuscin pigment granules. Here we show that relative food deprivation can cause accumulation of Lipofuscin pigmentation. We find that cardiac Lipofuscin deposition increases the most in the inequitable condition in which food deprived individuals observe well-fed individuals.

Conclusions/Significance

Our findings demonstrate that a sense of inequality in food intake can promote aging more than food deprivation alone. These findings should be considered as a basis for further studies on the physiological mechanisms by which inequality negatively impacts health and well-being.  相似文献   
92.
This study was performed to characterize the mechanical properties of the kidney capsular membrane at strain-rates associated with blunt abdominal trauma. Uniaxial quasi-static and dynamic tensile experiments were performed on fresh, unfrozen porcine and human renal capsules at deformation rates ranging from 0.0001 to 7 m/s (strain-rates of 0.005-250 s(-1)). Single stroke, dynamic tests were performed on samples of porcine renal capsule at strain-rates of 0.005 s(-1) (n = 33), 0.05 s(-1) (n = 17), 0.5 s(-1) (n = 38), 2 s(-1) (n = 10), 4 s(-1) (n = 10), 50 s(-1) (n = 21), 100 s(-1) (n = 18), 150 s(-1) (n = 17), 200 s(-1) (n = 10), and 250 s(-1) (n = 17). Due to limited availability of human tissues, only quasi-static tests were performed (0.005 s(-1), n = 25). Porcine renal capsule properties were found to match the material properties of human capsular tissue sufficiently well such that porcine tissue material can be used as a human test surrogate. The apparent elastic modulus and breaking stress of the porcine renal capsule were observed to increase significantly with increasing strain-rate (p < 0.01). Breaking strain was inversely related to strain-rate (p < 0.01). The effect of increasing strain-rate on material properties diminished appreciably at rates exceeding 150 s(-1). Empirically derived mathematical models of constitutive behavior were developed using a hyperelastic/viscoelastic Ogden formulation, as well as a Cowper-Symonds law material curve multiplication.  相似文献   
93.

Background  

In recent years, clustering algorithms have been effectively applied in molecular biology for gene expression data analysis. With the help of clustering algorithms such as K-means, hierarchical clustering, SOM, etc, genes are partitioned into groups based on the similarity between their expression profiles. In this way, functionally related genes are identified. As the amount of laboratory data in molecular biology grows exponentially each year due to advanced technologies such as Microarray, new efficient and effective methods for clustering must be developed to process this growing amount of biological data.  相似文献   
94.
Signal peptide (SP) is an important factor and biobrick in the production and secretion of recombinant proteins. The aim of this study was in silico and in vivo analysis of SPs effect on the production of recombinant glucose oxidase (GOX) in Yarrowia lipolytica. Several in silico softwares, namely SignalP4, Signal-CF, Phobius, WolfPsort 0.2, SOLpro and ProtParam, were used to analyse the potential of 15 endogenous and exogenous SPs for the secretion of recombinant GOX in Y. lipolytica. According to in silico results, the SP of GOX was predicted as suitable in terms of high secretory potential and of protein solubility and stability which is chosen for in vivo analysis. The recombinant Y. lipolytica strain produced 280 U/L of extracellular GOX after 7 days in YPD medium. The results show that the SP of GOX can be applied to efficient production of extracellular heterologous proteins and metabolic engineering in Y. lipolytica.  相似文献   
95.
The current study investigated the impacts of supplementation of post-weaning piglet diets with Macleaya cordata extract (MCE) and naringin (NAR) on performance, nutrient digestibility and intestinal histomorphology. Post-weaning crossbred piglets (28 males and 28 females; age at weaning 25 d) were randomly allotted to 28 pens. The experiment consisted of a control and three treatment groups (MCE60, MCE120 and NAR). For diets MCE60 and MCE120, the control diet was supplemented with 60 and 120 mg Sangrovit® Extra (a standardised premixture of MCE) per kg diet, respectively. Group NAR received 50 mg pure NAR per kg diet. The experiment lasted 42 d (d 25 – 66 of age). At d 66, apparent pre-caecal digestibility (APD) of nutrients was determined and histomorphological changes in mid-jejunum were evaluated. Feeding diets MCE120 and NAR improved body weight gain and feed conversion ratio of piglets. After feeding diets MCE120 and NAR, the APD of phosphorus and different single and total amino acids were greater than after feeding the control diet. The present data demonstrated that supplementation of post-weaning piglet diets with 120 mg MCE or 50 mg NAR per kg diet could improve growth performance and nutrient digestibility and had no impact on histomorphological variables in the jejunum. These findings indicate the potential of these products to be used as growth promoters in pig nutrition.  相似文献   
96.
The interaction between the dimer structure of ibuprofen drug (D-IB) and calf thymus DNA under simulative physiological conditions was investigated with the use of Hoechst 33258 and methylene blue dye as spectral probes by the methods of UV-visible absorption, fluorescence spectroscopy, circular dichroism spectroscopy and molecular modeling study.Using the Job's plot, a single class of binding sites for theD-IB on DNA was put in evidence. The Stern–Volmer analysis of fluorescence quenching data shows the presence of both the static and dynamic quenching mechanisms. The binding constants, Kb were calculated at different temperatures, and the thermodynamic parameters ?G°, ?H° and ?S° were given. The experimental results showed that D-IB molecules could bind with DNA via groove binding mode as evidenced by: I. DNA binding constant from spectrophotometric studies of the interaction of D-IB with DNA is comparable to groove binding drugs. II. Competitive fluorimetric studies with Hoechst 33258 have shown that D-IB exhibits the ability of this complex to displace with DNA-bounded Hoechst, indicating that it binds to DNA in strong competition with Hoechst for the groove binding. III. There is no significantly change in the absorption of the MB-DNA system upon adding the D-IB, indicates that MB molecules are not released from the DNA helix after addition of the D-IB and are indicative of a non-intercalative mode of binding. IV. Small changes in DNA viscosity in the presence of D-IB, indicating weak link to DNA, which is consistent with DNA groove binding. As well as, induced CD spectral changes, and the docking results revealed that groove mechanism is followed by D-IB to bind with DNA.  相似文献   
97.
98.
Abstract

The “bispecifics” market improved over the past decade due to the development of many technological platforms including bispecific T cell engagers (BiTEs). The approval of blinatumomab, the most advanced bispecific T-cell engager (BiTE) in clinical trials, can be a significant milestone in the development of bispecific antibodies. Both Chinese hamster ovary (CHO) cells and E. coli strain are considered as the most widely used hosts for the large-scale production of therapeutic monoclonal antibodies. Since both of the economic and qualitative aspects of protein production are important in industry, selection of a suitable protein expression system is very critical. The BsAb gene was cloned into the expression vectors FC550A-1, pcDNA3.1 (+), and PET22b and 6?×?His-tagged BsAb then purified on a Ni-NTA chromatography column. Both SDS–PAGE and Western blotting analysis of the purified protein demonstrated that blinatumomab was successfully expressed as a 55?kDa in both expression systems. The antigen-binding properties of blinatumomab were compared in the mammalian system versus Escherichia coli. The results showed that the purified antibody from a mammalian expression system has better binding activity than the one from E. coli host.  相似文献   
99.
Mooseer or Persian shallot (Allium hirtifolium Boiss.) is a bulbous perennial herb belonging to Alliaceae family. Genetic diversity of 16 mooseer populations collected from different parts of Iran were evaluated using 14 morphological traits as well as antioxidant activities and RAPD markers. Statistical analysis showed significant differences among populations for all morphological traits. In a principal component analysis, four components showed 77.5 % of the total morphological variation. Based on the morphological traits, populations were divided into five groups by clustering. Antioxidant capacities differed among all populations, with the Sahneh and Nahavand populations having the highest and the lowest activities, respectively. Genetic diversity of populations was also investigated through RAPD technique using 14 random primers. Cluster analysis based on RAPD markers plus 47 % coefficient of similarity divided the genotypes into six distinct groups. The highest and lowest similarities between populations were detected to be 0.63 and 0.21, respectively. These results indicated that the assessment of genetic diversity in Iranian mooseer populations could be appropriately carried out using RAPD technique which correlates with morphological traits.  相似文献   
100.
It is known that gamma activity is generated by local networks. In this paper we introduced a new approach for estimation of functional connectivity between neuronal networks by measuring temporal relations between peaks of gamma event amplitudes. We have shown in freely moving rats that gamma events recorded between electrodes 1.5 mm apart in the majority of cases, are generated by different neuronal modules interfering with each other. The map of functional connectivity between brain areas during the resting state, created based on gamma event temporal relationships is in agreement with anatomical connections and with maps described by fMRI methods during the resting state. The transition from the resting state to exploratory activity is accompanied by decreased functional connectivity between most brain areas. Our data suggest that functional connectivity between interhemispheric areas depends on GABAergic transmission, while intrahemispheric functional connectivity is kainate receptor dependent. This approach presents opportunities for merging electrographic and fMRI data on brain functional connectivity in normal and pathological conditions.  相似文献   
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