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181.
Anderson NL Razavi M Pearson TW Kruppa G Paape R Suckau D 《Journal of proteome research》2012,11(3):1868-1878
We have investigated the precision of peptide quantitation by MALDI-TOF mass spectrometry (MS) using six pairs of proteotypic peptides (light) and same-sequence stable isotope labeled synthetic internal standards (heavy). These were combined in two types of dilution curves spanning 100-fold and 2000-fold ratios. Coefficients of variation (CV; standard deviation divided by mean value) were examined across replicate MALDI spots using a reflector acquisition method requiring 100?000 counts for the most intense peak in each summed spectrum. The CV of light/heavy peptide centroid peak area ratios determined on four replicate spots per sample, averaged across 11 points of a 100-fold dilution curve and over all six peptides, was 2.2% (ranging from 1.5 to 3.7% among peptides) at 55 fmol total (light + heavy) of each peptide applied per spot, and 2.5% at 11 fmol applied. The average CV of measurements at near-equivalence (light = heavy, the center of the dilution curve) for the six peptides was 1.0%, about 17-fold lower CV than that observed when five peptides were ratioed to a sixth peptide (i.e., a different-sequence internal standard). Response curves across the 100-fold range were not completely linear but could be closely modeled by a power law fit giving R(2) values >0.998 for all peptides. The MALDI-TOF MS method was used to determine the endogenous level of a proteotypic peptide (EDQYHYLLDR) of human protein C inhibitor (PCI) in a plasma digest after enrichment by capture on a high affinity antipeptide antibody, a technique called stable isotope standards and capture by anti-peptide antibodies (SISCAPA). The level of PCI was determined to be 770 ng/mL with a replicate measurement CV of 1.5% and a >14?000-fold target enrichment via SISCAPA-MALDI-TOF. These results indicate that MALDI-TOF technology can provide precise quantitation of high-to-medium abundance peptide biomarkers over a 100-fold dynamic range when ratioed to same-sequence labeled internal standards and enriched to near purity by specific antibody capture. The robustness and throughput of MALDI-TOF in comparison to conventional nano-LC-MS technology could enable currently impractical large-scale verification studies of protein biomarkers. 相似文献
182.
Salehi H Karbalaie K Salamian A Kiani A Razavi S Nasr-Esfahani MH Baharvand H 《Stem cell research》2012,8(1):120-133
Limitations to the in vivo study of human nervous system development make it necessary to design an in vitro model to evaluate the in vivo effects of surrounding tissues on neurogenesis and regional identity of the human neural plate. Rostral neural progenitors (NPs) were initially generated from adherent human embryonic stem cells (hESCs) in a defined condition and characterized. Then, to find the role of somites (S) and notochords (N) in rostro-caudal (RC) and dorso-ventral (DV) patterning of neuronal cells, NPs were co-cultured with microencapsulated chicken S or N in alginate beads. In this study, N induced more neurogenesis as evaluated by expression of TUJ1 and MAP2-positive cells. Additionally, N induced spinal cord ventral brachiothoracic identity as well as NPs proliferation. We observed a synergic effect on motoneuron induction when S and N were used together. Moreover, S induced hindbrain identity in differentiated neuronal cells from NPs. These results indicate that highly enriched NPs can be generated in an adherent and defined system from hESCs. Moreover, S and N tissues highly influenced neuronal differentiation in point of proliferation, neurogenesis, and RC and DV regional identity. These results indicate a very simple and efficient protocol to mimic in vivo events of human neural development in vitro which is important in the context of developmental neuroscience and cellular replacement therapies. 相似文献
183.
Elham Moasser Seyed Reza Kazemi-Nezhad Mostafa Saadat Negar Azarpira 《Molecular biology reports》2012,39(12):10187-10192
Diabetes Mellitus is characterized by chronic hyperglycemia and associated with an increased production of reactive oxygen species (ROS). Oxidative stress is the result of accumulation of free radicals in tissues which specially affects beta cells in pancreas. Glutathione S-transferases (GSTs) are a family of antioxidant enzymes that include several classes of GSTs. These enzymes have important roles in decreasing of ROS species and act as a kind of antioxidant defense. To investigate the association between GSTs polymorphism with type 2 diabetes mellitus (T2DM), we investigated the frequency of GSTM1, T1 and P1 genotypes in patients with T2DM and controls. The genotypes of GSTT1, M1 and P1 were determined in 171 clinically documented T2DM patients and 169 normal cases (as controls) by multiplex polymerase chain reaction and PCR–RFLP. In diabetic patients, the frequency of GSTM1-null genotype was significantly (OR?=?1.74; 95?% CI?=?1.13–2.69, P?=?0.016) higher than that in control. However, the frequency of GSTT1 (OR?=?1.29; 95?% CI?=?0.07–2.14, P?=?0.367) and GSTP1 (OR?=?0.83; 95?% CI?=?0.53–1.30, P?=?0.389) genotypes were not significantly different comparing both groups. Also, the frequency of both GSTT1-null and GSTM1-null genotypes in patients (19.88?%) was significantly higher compared to controls with the same genotypes (11.83?%, P?=?0.022). Our results indicated that GSTM1 and GSTT1 genotypes might be involved in the pathogenesis of T2DM in south Iranian population. 相似文献
184.
Veshnyakova A Piontek J Protze J Waziri N Heise I Krause G 《The Journal of biological chemistry》2012,287(3):1698-1708
Claudins (Cld) are essential constituents of tight junctions. Domain I of Clostridium perfringens enterotoxin (cCPE) binds to the second extracellular loop (ECL2) of a subset of claudins, e.g. Cld3/4 and influences tight junction formation. We aimed to identify interacting interfaces and to alter claudin specificity of cCPE. Mutagenesis, binding assays, and molecular modeling were performed. Mutation-guided ECL2 docking of Cld3/4 onto the crystal structure of cCPE revealed a common orientation of the proposed ECL2 helix-turn-helix motif in the binding cavity of cCPE: residues Leu(150)/Leu(151) of Cld3/4 bind similarly to a hydrophobic pit formed by Tyr(306), Tyr(310), and Tyr(312) of cCPE, and Pro(152)/Ala(153) of Cld3/4 is proposed to bind to a second pit close to Leu(223), Leu(254), and Leu(315). However, sequence variation in ECL2 of these claudins is likely responsible for slightly different conformation in the turn region, which is in line with different cCPE interaction modes of Cld3 and Cld4. Substitutions of other so far not characterized cCPE residues lining the pocket revealed two spatially separated groups of residues (Leu(223), Asp(225), and Arg(227) and Leu(254), lle(258), and Asp(284)), which are involved in binding to Cld3 and Cld4, albeit differently. Involvement of Asn(148) of Cld3 in cCPE binding was confirmed, whereas no evidence for involvement of Lys(156) or Arg(157) was found. We show structure-based alteration of cCPE generating claudin binders, which interact subtype-specific preferentially either with Cld3 or with Cld4. The obtained mutants and mechanistic insights will advance the design of cCPE-based modulators to target specific claudin subtypes related either to paracellular barriers that impede drug delivery or to tumors. 相似文献
185.
Seyed Mehdi Razavi Saber Zahri Gholamreza Zarrini Hossein Nazemiyeh Sariyeh Mohammadi 《Russian Journal of Bioorganic Chemistry》2009,35(3):376-378
Cytotoxic, phytotoxic, antimicrobial and antioxidant effects of quercetin 3-O-glucoside (Q3G) isolated by HPLC from aerial parts of Prangos ferulaceae was studied by MTT assay, lettuce germination assay, disk diffusion and DPPH method. Our results showed that Q3G exhibits
high antioxidant effect with RC50 of 22 μg/mL, it has low cytotoxicity and no antibacterial effects. Q3G exhibits high phytotoxic effect with IC50 value of 282.7 μg/ml, as well. It is assumed that Q3G does not play a defense role in plants and it may act as an allelopatic
agent.
The article is published in the original. 相似文献
186.
Yehia G Schlotter F Razavi R Alessandrini A Molina CA 《The Journal of biological chemistry》2001,276(38):35272-35279
Inducible cAMP early repressor (ICER) is an important mediator of cAMP antiproliferative activity that acts as a putative tumor suppressor gene product. In this study, we examined the regulation of ICER protein by phosphorylation and ubiquitination in human choriocarcinoma JEG-3 and mouse pituitary AtT20 cells. We found that cAMP stabilized ICER protein by inhibiting the mitogen-activated protein kinase (MAPK) cascade. Activation of the MAPK pathway increased ICER phosphorylation. ICER phosphorylation was abrogated by inhibition of the MAPK pathway either by cAMP or directly by the MAPK inhibitor PD098059. The MAPKs extracellular signal-regulated kinases 1 and 2 physically interact with ICER and mediated the phosphorylation of ICER on a critical serine residue (Ser-41). A mutant form of ICER in which Ser-41 was substituted by alanine had a half-life 4-5 h longer than its wild-type counterpart. This alteration in stability was due to the inability of the Ser-41-mutant ICER to be efficiently ubiquitinated and degraded via the ubiquitin-proteasome pathway. These results present a novel cell signaling cross-talk mechanism at the cell nucleus between the MAPK and cAMP pathways, whereby MAPK targets a repressor of the cAMP-dependent gene expression for ubiquitination and proteasomal degradation. 相似文献
187.
Ehsaneh Azaryan Fariba Emadian Razavi Mohammad Yahya Hanafi-Bojd Esmat Alemzadeh Mohsen Naseri 《Biotechnology progress》2023,39(2):e3319
Missing or damaged teeth due to caries, genetic disorders, oral cancer, or infection may contribute to physical and mental impairment that reduces the quality of life. Despite major progress in dental tissue repair and those replacing missing teeth with prostheses, clinical treatments are not yet entirely satisfactory, as they do not regenerate tissues with natural teeth features. Therefore, much of the focus has centered on tissue engineering (TE) based on dental stem/progenitor cells to create bioengineered dental tissues. Many in vitro and in vivo studies have shown the use of cells in regenerating sections of a tooth or a whole tooth. Tooth tissue engineering (TTE), as a promising method for dental tissue regeneration, can form durable biological substitutes for soft and mineralized dental tissues. The cell-based TE approach, which directly seeds cells and bioactive components onto the biodegradable scaffolds, is currently the most potential method. Three essential components of this strategy are cells, scaffolds, and growth factors (GFs). This study investigates dentin regeneration after an injury such as caries using TE and stem/progenitor cell-based strategies. We begin by discussing about the biological structure of a dentin and dentinogenesis. The engineering of teeth requires knowledge of the processes that underlie the growth of an organ or tissue. Then, the three fundamental requirements for dentin regeneration, namely cell sources, GFs, and scaffolds are covered in the current study, which may ultimately lead to new insights in this field. 相似文献
188.
Mahshid Torkzaban Morteza Zendehdel Vahab Babapour Negar Panahi Shahin Hassanpour 《International journal of peptide research and therapeutics》2018,24(1):157-169
The present study was designed to examine the role of opioidergic and glutamatergic systems on feeding behavior in neonatal meat-type chicken. In experiment 1, FD3 neonatal broilers ICV injected with (A) saline, (B) DAMGO (µ-opioid receptor agonist, 125 pmol), (C) MK-801 (NMDA glutamate receptors antagonist, 15 nmol) and (D) combination of DAMGO plus MK-801. Experiments 2–5 were similar to experiment 1, except FD3 chicks ICV injected with CNQX (AMPA glutamate receptors antagonist, 390 nmol), AIDA (mGLU1 receptors antagonist, 2 nmol), LY341495 (mGLU2 receptors antagonist, 150 nmol) and UBP1112 (mGLU3 receptors antagonist, 2 nmol) instead of MK-801, respectively. In experiments 6–10, FD3 chicks ICV injected as the same as procedure to the experiments 1–5, except to inject with DPDPE (δ-opioid receptor agonist, 40 nmol) instead of the DAMGO. The experiments 11–15 were similar to the experiments 1–5, except neonatal broilers ICV injected with U-50488H (κ-opioid receptor agonist, 30 nmol) instead of DAMGO. Then the cumulative food intake measured until 120 min post injection. According to the results, ICV injection of DAMGO, significantly decreased food intake (P?<?0.05) while DPDPE and U-50488H increased feeding behavior compared to the control group (P?<?0.05). Co-injection of the DAMGO?+?MK-801 and DAMGO?+?AIDA, significantly decreased DAMGO-induced hypophagia in neonatal chicks (P?<?0.05). Also, co-injection of the DPDPE?+?CNQX significantly amplified DPDPE induced feeding behavior (P?<?0.05). These results suggested interconnection between central opioidergic and glutamatergic systems on feeding behavior mediates via µ- and δ-opioid receptor with NMDA, AMPA and mGLU1 receptors in FD3 neonatal broilers. These findings may shed light on the circuitry underlying interconnection between central opioidergic and glutamatergic systems on feeding behavior. 相似文献
189.
Negar Firouzabadi Nima Ghazanfari Ali Alavi Shoushtari Nasrallah Erfani Farshid Fathi Mozhdeh Bazrafkan Ehsan Bahramali 《PloS one》2016,11(4)
BackgroundAutism is a disease of complex nature with a significant genetic component. The importance of renin-angiotensin system (RAS) elements in cognition and behavior besides the interaction of angiotensin II (Ang II), the main product of angiotensin-converting enzyme (ACE), with neurotransmitters in CNS, especially dopamine, proposes the involvement of RAS in autism. Since the genetic architecture of autism has remained elusive, here we postulated that genetic variations in RAS are associated with autism.MethodsConsidering the relation between the three polymorphisms of ACE (I/D, rs4343 and rs4291) with the level of ACE activity, we have investigated this association with autism, in a case-control study. Genotype and allele frequencies of polymorphisms were determined in DNAs extracted from venous blood of 120 autistic patients and their age and sex-matched healthy controls, using polymerase chain reaction (PCR) and PCR–restriction fragment length polymorphism (PCR–RFLP) methods.ResultsThere were strong associations between both DD genotype of ACE I/D and the D allele, with autism (P = 0.006, OR = 2.9, 95% CI = 1.64–5.13 and P = 0.006, OR = 2.18, 95% CI = 1.37–3.48 respectively). Furthermore, a significant association between the G allele of rs4343 and autism was observed (P = 0.006, OR = 1.84, 95%CI = 1.26–2.67). Moreover, haplotype analysis revealed an association between DTG haplotype and autism (P = 0.008).ConclusionOur data suggests the involvement of RAS genetic diversity in increasing the risk of autism. 相似文献
190.
Watkins WJ Chong L Cho A Hilgenkamp R Ludwikow M Garizi N Iqbal N Barnard J Singh R Madsen D Lolans K Lomovskaya O Oza U Kumaraswamy P Blecken A Bai S Loury DJ Griffith DC Dudley MN 《Bioorganic & medicinal chemistry letters》2007,17(10):2802-2806
Further structure-activity relationships of a novel series of fungal efflux pump inhibitors with respect to potentiation of the activity of fluconazole against strains of C. albicans and C. glabrata over-expressing ABC-type efflux pumps are systematically explored. Rat protein binding and pharmacokinetics of selected analogues are reported. 相似文献