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1.

Background

Emerging evidence showed that VEGF gene polymorphisms are involved in the regulation of VEGF protein expression, thus increasing an individual''s susceptibility to preeclampsia (PE); but individually published results are inconclusive. The aim of this meta-analysis was to investigate the associations between VEGF gene polymorphisms and PE risk.

Methods

A systematic literature search of MEDLINE, Embase, Web of Science, and CNKI (Chinese National Knowledge Infrastructure) databases was conducted. Statistical analyses were performed using STATA 12.0 software and Review manager 5.1. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of associations.

Results

According to the inclusion criteria, 11 case-control studies were finally included in this meta-analysis. A total of 1,069 PE cases and 1,315 controls were included in this study. Our meta-analysis indicated that VEGF +936C/T (T vs. C, OR = 1.52, 95%CI = 1.08–2.12) or −634G/C polymorphism (C vs. G, OR = 1.24, 95% CI = 1.03–1.50) was associated with the risk of PE, whereas there was no association between −2578C/A (A vs. C, OR = 0.98, 95%CI = 0.82–1.16) or −1154G/A (A vs. G, OR = 1.30, 95%CI = 0.94–1.78) polymorphism and PE risk in our study.

Conclusion

Our meta-analysis suggested that VEGF −2578C/A or −1154G/A polymorphism had no association with PE risk in all examined patients, whereas there was an association between VEGF +936C/T or −634G/C polymorphism and risk of PE.  相似文献   

2.
Lactobacillus casei strains are widely used in industry and the utility of this organism in these industrial applications is strain dependent. Hence, tools capable of predicting strain specific phenotypes would have utility in the selection of strains for specific industrial processes. Genome-scale metabolic models can be utilized to better understand genotype-phenotype relationships and to compare different organisms. To assist in the selection and development of strains with enhanced industrial utility, genome-scale models for L. casei ATCC 334, a well characterized strain, and strain 12A, a corn silage isolate, were constructed. Draft models were generated from RAST genome annotations using the Model SEED database and refined by evaluating ATP generating cycles, mass-and-charge-balances of reactions, and growth phenotypes. After the validation process was finished, we compared the metabolic networks of these two strains to identify metabolic, genetic and ortholog differences that may lead to different phenotypic behaviors. We conclude that the metabolic capabilities of the two networks are highly similar. The L. casei ATCC 334 model accounts for 1,040 reactions, 959 metabolites and 548 genes, while the L. casei 12A model accounts for 1,076 reactions, 979 metabolites and 640 genes. The developed L. casei ATCC 334 and 12A metabolic models will enable better understanding of the physiology of these organisms and be valuable tools in the development and selection of strains with enhanced utility in a variety of industrial applications.  相似文献   

3.
The structures of four different RNA pseudoknots that provide one of the signals required for ribosomal frameshifting in mouse mammary tumor virus have been determined by NMR. The RNA pseudoknots have similar sequences and assume similar secondary structures, but show significantly different frameshifting efficiencies. The three-dimensional structures of one frameshifting and one non-frameshifting RNA pseudoknot had been determined previously by our group. Here we determine the structures of two new RNA pseudoknots, and relate the structures of all four pseudoknots to their frameshifting abilities. The two efficient frameshifting pseudoknots adopt characteristic bent conformations with stem 1 bending towards the major groove of stem 2. In contrast, the two poor frameshifting pseudoknots have structures very different from each other and from the efficient frameshifters. One has linear, coaxially stacked stems, the other has stems twisted and bent, but in the opposite direction to the efficient frameshifters. Changes in loop size that favor bending (shorter loops) increase frameshifting efficiency; longer loops that allow linear arrangement of the stems decrease frameshifting. Frameshifting pseudoknots in feline immunodeficiency virus and simian retrovirus have different loop sequences, but the sequences at their stem junctions imply the same bent conformation as in the mouse mammary tumor viral RNA. The requirement for a precise pseudoknot conformation for efficient frameshifting strongly implies that a specific interaction occurs between the viral RNA pseudoknot and the host protein-synthesizing machinery.  相似文献   

4.
Diabetic retinopathy, is a microvascular complication of diabetes mellitus and is a major cause of adult blindness. Despite advances in diagnosis and treatment the pathogenesis of diabetic retinopathy is not well understood. Results from epidemiological studies of diabetic patients suggest that there are familial predispositions to diabetes and to diabetic retinopathy. Therefore the main purpose of this database is to help both scientists and doctors in studying the candidate genes responsible for causing diabetic retinopathy. For each candidate gene official symbol, chromosome map, number of exons, GT-AG introns, motif, polymorphic variation and 3D structure are given respectively. In addition to molecular class and function of these genes, this database also provides links to download the corresponding nucleotide and amino acid sequences in FASTA format which may be further used for computational approaches. Therefore this database will increase the understanding of the genetics underlying the development or progression of diabetic retinopathy and will have an impact on future diagnostic, prevention and intervention strategies.

Availability

The database is freely available at http: diaretinopathydatabase.com  相似文献   

5.
6.
Resonance Raman studies have uncovered puzzling complexities in the structures of NO adducts of heme proteins. Although CO adducts of heme proteins obey well-behaved anti-correlations between Fe–C and C–O stretching frequencies, which reflect changes in backbonding induced by distal H-bonding residues, the corresponding NO data are scattered. This scatter can be traced to distal influences, since protein-free NO–hemes do show well-behaved anti-correlations. Why do distal effects produce irregularities in νFeN/νNO plots but not in νFeC/νCO plots? We show via density functional theory (DFT) computations on model systems that the response to distal H-bonding differs markedly when the NO acceptor atom is N versus O. Backbonding is augmented by H-bonding to O, but the effect of H-bonding to N is to weaken both N–O and N–Fe bonds. The resulting downward deviation from the νFeN/νNO backbonding line increases with increasing H-bond strength. This effect explains the deviations observed for a series of myoglobin variants, in which the strength of distal H-bonding is modulated by distal pocket residue substitutions. Most of the data follow a positive νFeN/νNO correlation with the same slope as that calculated for H-bonding to N. Such deviations are not observed for CO adducts, because the CO π* orbital is unoccupied, and serves as a delocalized acceptor of H-bonds. H-bonding to N primes NO–heme for reduction to the HNO adduct, a putative intermediate in NO-reducing enzymes.  相似文献   

7.
8.
Bradykinin exerts its vascular actions via two types of receptors, the non-constitutively expressed bradykinin receptor type 1 (BR1) and the constitutive type 2 receptor (BR2). Bradykinin-induced vasorelaxation is age-dependent, a phenomenon related to the varying amounts of BR1 and BR2 in the vasculature.Isoleucine-proline-proline (Ile-Pro-Pro), a bioactive tripeptide, lowers elevated blood pressure and improves impaired endothelium-dependent vasorelaxation in hypertensive rats. It inhibits angiotensin converting enzyme 1 (ACE1). Other mechanisms of action have also been postulated.The aims of the study were to clarify the underlying mechanisms of the age-dependency of bradykinin-induced vasodilatation such as the roles of the two bradykinin receptors, the mas-receptor and synergism with Ile-Pro-Pro.The vascular response studies were conducted using mesenteric artery and aorta rings from normotensive 6 wk. (young) and 22 wk. (old) Wistar rats. Cumulative dosing of acetylcholine, bradykinin and angiotensin(1–7) (Ang(1–7))were tested in phenylephrine-induced vasoconstriction with or without 10 min pre-incubation with antagonists against BR1-, BR2- or mas-receptors, Ang(1–7) or ACE1-inhibitors captopril and Ile-Pro-Pro.The bradykinin-induced vasorelaxation in vitro was age-dependent and it was improved by pre-incubation with Ile-Pro-Pro, especially in old rats with endothelial dysfunction. The mas-receptor antagonist, D-Pro7-Ang(1–7) abolished bradykinin-induced relaxation totally. Interestingly, BR1 and BR2 antagonists only slightly reduced bradykinin-induced vasorelaxation, as an evidence for the involvement of other mechanisms in addition to receptor activation.In conclusion, bradykinin-induced vasorelaxation was age-dependent and Ile-Pro-Pro improved it. Mas receptor antagonist abolished relaxation while bradykinin receptor antagonist only slightly reduced it, suggesting that bradykinin-induced vasorelaxation is regulated also by other mechanisms than the classical BR1/BR2 pathway.  相似文献   

9.
In 2017, a Special Issue of Biophysical Reviews was devoted to “Titin and Its Binding Partners. The issue contained a review: “An historical perspective of the discovery of titin filaments” by dos Remedios and Gilmour that was intended to be a history of the discovery of the giant protein titin, previously named connectin. The review took readers back to the earliest discovery of the so-called third filament component of skeletal and cardiac muscle sarcomeres and ended in 1969. Recently, my colleague Shin’ichi Ishiwata gently reminded me of two papers published in 1990 and 1993 that were unwittingly omitted from the original historical perspective. In the first paper (J Cell Biol 110:53–62, 1990), Funatsu et al. examined the elastic filaments in skeletal muscle using a combination of light and electron microscopy, but they also measured resting as well as passive stiffness mechanical measurements to establish that connectin (titin) is responsible for both stiffness and fiber tension. In the second paper (J Cell Biol 120:711–724, 1993), Funatsu et al. used permeabilised cardiac muscle myocytes (from rabbit papillary muscles) and focussed on filament ultrastructure using either freeze-substitution or deep-etched replica methods to visualise connectin/titin filaments in fibers with and without actin and myosin filaments.  相似文献   

10.
The C1 domains of classical and novel PKCs mediate their diacylglycerol-dependent translocation. Using fluorescence resonance energy transfer, we studied the contribution of different negatively charged phospholipids and diacylglycerols to membrane binding. Three different C1B domains of PKCs were studied (the classical γ, and the novel δ and ?), together with different lipid mixtures containing three types of acidic phospholipids and three types of activating diacylglycerols. The results show that C1Bγ and C1B? exhibit a higher affinity to bind to vesicles containing 1-palmitoyl-2-oleoyl-sn-phosphatidic acid, 1-palmitoyl-2-oleoyl-sn-phoshatidylserine, or 1-palmitoyl-2-oleoyl-sn-phosphatidylglycerol, with C1B? being the most relevant case because its affinity for POPA-containing vesicles increased by almost two orders of magnitude. When the effect of the diacylglycerol fatty acid composition on membrane binding was studied, the C1B? domain showed the highest binding affinity to membranes containing 1-stearoyl-oleoyl-sn-glycerol or 1,2-sn-dioleoylglycerol with POPA as the acidic phospholipid. Of the three diacylglycerols used in this study, 1,2-sn-dioleoylglycerol and 1-stearoyl-oleoyl-sn-glycerol showed the highest affinities for each isoenzyme, whereas 1,2-sn-dipalmitoylglycerol; showed the lowest affinity. DSC experiments showed this to be a consequence of the nonfluid conditions of 1,2-sn-dipalmitoylglycerol;-containing systems.  相似文献   

11.
Nuclear magnetic resonance (NMR) spectroscopy acts as the best tool that can be used in tissue engineering scaffolds to investigate unknown metabolites. Moreover, metabolomics is a systems approach for examining in vivo and in vitro metabolic profiles, which promises to provide data on cancer metabolic alterations. However, metabolomic profiling allows for the activity of small molecules and metabolic alterations to be measured. Furthermore, metabolic profiling also provides high-spectral resolution, which can then be linked to potential metabolic relationships. An altered metabolism is a hallmark of cancer that can control many malignant properties to drive tumorigenesis. Metabolite targeting and metabolic engineering contribute to carcinogenesis by proliferation, and metabolic differentiation. The resulting the metabolic differences are examined with traditional chemometric methods such as principal component analysis (PCA), and partial least squares-discriminate analysis (PLS-DA). In this review, we examine NMR-based activity metabolomic platforms that can be used to analyze various fluxomics and for multivariant statistical analysis in cancer. We also aim to provide the reader with a basic understanding of NMR spectroscopy, cancer metabolomics, target profiling, chemometrics, and multifunctional tools for metabolomics discrimination, with a focus on metabolic phenotypic diversity for cancer therapeutics.  相似文献   

12.
An efficient regeneration protocol for Sarcostemma acidum – an important medicinal plant has been established. Callus initiated from nodal explant on MS medium with 2.0 mg?L?1 of NAA + additives. Callus initiated was subcultured on MS medium containing various concentrations of NAA or 2,4-D. Out of these combinations, MS medium +1.0 mg?L?1 of NAA + additives was found to be effective for the multiplication of callus. Subculture was done after an interval of 20–22 days. For differentiation of callus BAP or Kinetin alone was found to be less effective. Maximum frequency of shoot regeneration recorded on MS medium +1.0 mg?L?1 of BAP?+?0.5 mg?L?1 of Kinetin and 0.1 mg?L?1 of NAA + additives. The in vitro differentiated shoots were excised and inoculated on 1/4 strength MS medium +2.0 mg?L?1 of IBA?+?0.02 % activated charcoal for in vitro rooting. Maximum response (90 %) was recorded on this medium. In vitro differentiated shoots were inoculated on autoclaved soilrite® after treatment with root inducing auxins. Ex vitro rooting in this plant species has been reported for the first time. Eighty five percent of the shoots rooted under ex vitro conditions. Both in vitro and ex vitro rooted plantlets were hardened in a green house.  相似文献   

13.
Cytogenetic and molecular genetic studies of an intersex horse have been carried out. The investigated animal had overall male body conformation; however, its external genitalia consisted of incompletely developed vulva and penis. The X and Y chromosome painting probes detected three cell lines in the examined horse: 63,X, 64,XX and 65,XX with a fragment of a Y chromosome (del Y). The DNA analysis with the PCR and PCR/RFLP methods showed absence of SRY,AMELY and ZFY genes as well as of six Y microsatellite markers (YM2, YP9, YJ10, YE1, YH12, and YA16). These results suggest that the Y chromosome fragment detected in the investigated animal was the result of a deletion of a euchromatic fragment comprising the above-mentioned markers.  相似文献   

14.
During pregnancy, a series of physiological changes are determined at the molecular, cellular and macroscopic level that make the mother and fetus more susceptible to certain viral and bacterial infections, especially the infections in this and the companion review. Particular situations increase susceptibility to infection in neonates. The enhanced susceptibility to certain infections increases the risk of developing particular diseases that can progress to become morbidly severe. For example, during the current pandemic caused by the SARS-CoV-2 virus, epidemiological studies have established that pregnant women with COVID-19 disease are more likely to be hospitalized. However, the risk for intensive care unit admission and mechanical ventilation is not increased compared with nonpregnant women. Although much remains unknown with this particular infection, the elevated risk of progression during pregnancy towards more severe manifestations of COVID-19 disease is not associated with an increased risk of death. In addition, the epidemiological data available in neonates suggest that their risk of acquiring COVID-19 is low compared with infants (<12 months of age). However, they might be at higher risk for progression to severe COVID-19 disease compared with older children. The data on clinical presentation and disease severity among neonates are limited and based on case reports and small case series. It is well documented the importance of the Zika virus infection as the main cause of several congenital anomalies and birth defects such as microcephaly, and also adverse pregnancy outcomes. Mycoplasma infections also increase adverse pregnancy outcomes. This review will focus on the molecular, pathophysiological and biophysical characteristics of the mother/placental-fetal/neonatal interactions and the possible mechanisms of these pathogens (SARS-CoV-2, ZIKV, and Mycoplasmas) for promoting disease at this level.  相似文献   

15.
In this study, we used native gradient-polyacrylamide gel electrophoresis and electroelution (NGGEE) to purify enzymatic proteins from Trichoderma koningii AS3.2774. With this method, we purified eight enzymatic proteins and classified them to the cellulase system by comparing secretions of T. koningii in inductive medium and in repressive medium. It resulted in 24-fold β-glucosidase (BG) purification with a recovery rate of 5.5%, and a specific activity of 994.6 IU mg− 1 protein. The final yield of BG reached 8 μg under purifying procedure of NGGEE. We also identified BG using the enzyme assay with thin-layer chromatography and MALDI-TOFMS. This BG had one subunit with a molecular mass of 69.1 kDa as determined by sodium dodecylsulfate-polyacrylamide gel electrophoresis. The hydrolytic activity of the BG had an optimal pH of 5.0, an optimal temperature of 50 °C, an isoelectric point of 5.68 and a Km for p-nitrophenyl-β-d-glucopyranoside of 2.67 mM. Taken together, we show that NGGEE is a reliable method through which μg grade of active proteins can be purified.  相似文献   

16.
17.

Aims

Panduratin A isolated from Boesenbergia pandurata (Roxb.) has been reported to have antioxidant, anti-inflammatory, and anti-allergic activities. However, the effect of panduratin A on atopic dermatitis (AD) has not been studied. In the present study, we investigated the efficacy of panduratin A, an activator of peroxisome proliferator-activated receptors (PPAR) α/δ, using oxazolone-induced AD-like model in hairless mice.

Main methods

To determine PPARα/δ activation of panduratin A, HaCaT, Hs68, and COS-7 cells were treated with panduratin A, then PPARα/δ and PPAR response element (PPRE) activities were assessed with a reporter gene assay. For the in vivo study, oral administration of panduratin A was performed for 4 weeks, with oxazolone treatment every other day. The efficacy of panduratin A on parameters of oxazolone-induced AD was assessed physiologically, morphologically, and immunologically.

Key findings

Panduratin A increased PPARα/δ and PPRE activation both in vitro and in vivo. Panduratin A attenuated dermatitis-associated barrier damage as demonstrated by transepidermal water loss, erythema, and filaggrin expression. Furthermore, infiltration of inflammatory cells and epidermal thickness in the skin were decreased. Panduratin A decreased serum immunoglobulin (Ig) E and interleukin-4 levels but increased IgG2a and interferon-γ levels. In addition, panduratin A decreased inflammation-associated molecules in the skin. Panduratin A also decreased Th2-associated molecules and increased Th1/regulatory T cell (Treg)-associated molecules in the spleen.

Significance

Panduratin A showed a beneficial effect on AD by modulating Th1/Th2/Treg-associated immune response and is a potential candidate for treating AD.  相似文献   

18.
The objective of this paper is to give an overview of existing databases in Denmark and describe some of the most important of these in relation to establishment of the Danish Veterinary and Food Administrations’ veterinary data warehouse. The purpose of the data warehouse and possible use of the data are described. Finally, sharing of data and validity of data is discussed. There are databases in other countries describing animal husbandry and veterinary antimicrobial consumption, but Denmark will be the first country relating all data concerning animal husbandry, -health and -welfare in Danish production animals to each other in a data warehouse. Moreover, creating access to these data for researchers and authorities will hopefully result in easier and more substantial risk based control, risk management and risk communication by the authorities and access to data for researchers for epidemiological studies in animal health and welfare.  相似文献   

19.
We employ ensemble docking simulations to characterize the interactions of two enantiomeric forms of a Ru-complex compound (1-R and 1-S) with three protein kinases, namely PIM1, GSK-3β, and CDK2/cyclin A. We show that our ensemble docking computational protocol adequately models the structural features of these interactions and discriminates between competing conformational clusters of ligand-bound protein structures. Using the determined X-ray crystal structure of PIM1 complexed to the compound 1-R as a control, we discuss the importance of including the protein flexibility inherent in the ensemble docking protocol, for the accuracy of the structure prediction of the bound state. A comparison of our ensemble docking results suggests that PIM1 and GSK-3β bind the two enantiomers in similar fashion, through two primary binding modes: conformation I, which is very similar to the conformation presented in the existing PIM1/compound 1-R crystal structure; conformation II, which represents a 180° flip about an axis through the NH group of the pyridocarbazole moiety, relative to conformation I. In contrast, the binding of the enantiomers to CDK2 is found to have a different structural profile including a suggested bound conformation, which lacks the conserved hydrogen bond between the kinase and the ligand (i.e., ATP, staurosporine, Ru-complex compound). The top scoring conformation of the inhibitor bound to CDK2 is not present among the top-scoring conformations of the inhibitor bound to either PIM1 or GSK-3β and vice-versa. Collectively, our results help provide atomic-level insights into inhibitor selectivity among the three kinases.
Figure
Top cluster of predicted conformations based on ensemble docking simulations of a Ruthenium based compound to protein kinases  相似文献   

20.
In this study, we have systematically compared the uranyl photocleavage of a range of bent A-tracts and nonbent TA-tracts as well as interrupted A-tracts. We demonstrate that uranyl photocleavage of A-tracts and TA-tracts is almost identical, indicating a very similar minor groove conformation. Furthermore, a 10 base pair A-tract is divided into two independent tracts by an intervening TA or GC step. Uranyl probing also clearly distinguishes the bent A4T4 and the nonbent T4A4 sequences as adopting different structures, and our interpretation of the data is consistent with a structure for the bent A4T4 sequence that resembles a continuous A-tract, whereas the nonbent T4A4 sequences are closer to two independent and opposite A-tracts that cancel each other in terms of macroscopic bending. Finally, we also note that even single TA and TAT steps are highly sensitive to uranyl photocleavage and propose that in addition to average minor groove width, uranyl also senses DNA helix flexibility/deformability. Thus, the structural difference of TA-tracts and A-tracts may to a large extent reflect a difference in flexibility, and DNA curvature may consequently require a rigid narrow minor groove conformation that creates distinct A-tract-B-DNA junctions as the predominant cause of the bending.  相似文献   

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