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61.
Z. E. Mousavi S. M. Mousavi S. H. Razavi Z. Emam-Djomeh H. Kiani 《World journal of microbiology & biotechnology》2011,27(1):123-128
In this research, production of probiotic pomegranate juice through its fermentation by four strains of lactic acid bacteria:
Lactobacillus plantarum, L. delbruekii, L. paracasei, L. acidophilus was examined. Fermentation was carried out at 30°C for 72 h under microaerophilic conditions. Microbial population, pH, titrable
acidity, sugar and organic acid metabolism were measured during the fermentation period and the viability of all strains was
also determined during the storage time at 4°C within 4 weeks. The results indicated that L. plantarum and L. delbruekii increased the pH sharply at the initial stages of fermentation and the sugar consumption was also higher in comparison with
other strains, better microbial growth was also observed for these two strains during fermentation. Citric acid, as a major
organic acid in pomegranate juice was significantly consumed by all probiotic lactic acid bacteria. L. plantarum and L. delbruekii showed higher viability during the storage time. Viable cells remained at their maximum level within 2 weeks but decreased
dramatically after 4 weeks. Pomegranate juice was proved to be a suitable media for production of a fermented probiotic drink. 相似文献
62.
Mahdavi A Sajedi RH Asghari SM Taghdir M Rassa M 《International journal of biological macromolecules》2011,49(5):1038-1045
A comparative biochemical and structural study was performed on a cold active α-amylase from Bacillus cereus (BCA) and two well-known homologous mesophilic and thermophilic α-amylases from Bacillus amyloliquefaciens (BAA) and Bacillus licheniformis (BLA). In spite of a high degree of sequence and structural similarity, drastic variations were found for Topt as 50, 70 and 90 °C for BCA, BAA and BLA, respectively. The half-lives of thermoinactivation were 1 and 9 min for BCA and BAA at 80 °C respectively, whilst there was no inactivation for BLA at this temperature. Thermodynamic studies on inactivation process suggested that lower thermostability of BCA is due to lower inactivation slope of the Arrhenius plots and subsequently, lower Ea and ΔH#. Increased Km and accessible surface area for catalytic residues along with a decreased number of internal interactions in this region in BCA compared to BLA suggest that BCA substrate-binding site might be temperature sensitive and is probably more flexible. On the other hand, fewer ion pairs, destructive substitutions and disruption of aromatic interaction networks in structurally critical regions of Bacillus α-amylases result in a severe decrease in BCA thermostability compared to its mesophilic and thermophilic homologues. 相似文献
63.
Teresa Cabezón Irina Gromova Pavel Gromov Reza Serizawa Vera Timmermans Wielenga Niels Kroman Julio E. Celis José M. A. Moreira 《Molecular & cellular proteomics : MCP》2013,12(2):381-394
Breast cancer is a very heterogeneous disease, encompassing several intrinsic subtypes with various morphological and molecular features, natural history and response to therapy. Currently, molecular targeted therapies are available for estrogen receptor (ER)− and human epidermal growth factor receptor 2 (Her2)-positive breast tumors. However, a significant proportion of primary breast cancers are negative for ER, progesterone receptor (PgR), and Her2, comprising the triple negative breast cancer (TNBC) group. Women with TNBC have a poor prognosis because of the aggressive nature of these tumors and current lack of suitable targeted therapies. As a consequence, the identification of novel relevant protein targets for this group of patients is of great importance. Using a systematic two dimensional (2D) gel-based proteomic profiling strategy, applied to the analysis of fresh TNBC tissue biopsies, in combination with a three-tier orthogonal technology (two dimensional PAGE/silver staining coupled with MS, two dimensional Western blotting, and immunohistochemistry) approach, we aimed to identify targetable protein markers that were present in a significant fraction of samples and that could define therapy-amenable sub-groups of TNBCs. We present here our results, including a large cumulative database of proteins based on the analysis of 78 TNBCs, and the identification and validation of one specific protein, Mage-A4, which was expressed in a significant fraction of TNBC and Her2-positive/ER negative lesions. The high level expression of Mage-A4 in the tumors studied allowed the detection of the protein in the tumor interstitial fluids as well as in sera. The existence of immunotherapeutics approaches specifically targeting this protein, or Mage-A protein family members, and the fact that we were able to detect its presence in serum suggest novel management options for TNBC and human epidermal growth factor receptor 2 positive/estrogen receptor negative patients bearing Mage-A4 positive tumors.Breast cancer, although a very heterogeneous disease, can be divided into three therapeutically relevant fundamental disease entities, simply based on estrogen receptor (ER) and human epidermal growth factor receptor 2 (Her2)1 status (i.e. ER+ and/or Her2+, and ER−Her2−), as the major currently available breast cancer therapeutic options are based on the ability to target these proteins. Hormone receptor positive and hormone receptor negative breast cancers are disease entities with distinct morphological, genetic and biological behavior (1). Hormone receptor negative tumors, which constitute ∼30% of primary breast cancers, tend to be high-grade, more frequently BRCA1 and TP53 mutated, and, more importantly, are not amenable to endocrine therapy. Her2 is amplified in ∼18–20% of breast cancers, and is more frequently observed in hormone receptor negative tumors. Her2 amplification is associated with worse prognosis (higher rate of recurrence and mortality) in patients with newly diagnosed breast cancer who do not receive any adjuvant systemic therapy. Her2 status is also predictive for several systemic therapies, particularly for agents that target Her2. The development of a humanized monoclonal antibody against Her2 (trastuzumab) has resulted in reduction of the risk of recurrence and mortality in patients with Her2 amplification (2, 3). Although trastuzumab is considered one of the most effective targeted therapies currently available in oncology, a significant number of patients with Her2-overexpressing breast cancer do not benefit from it (4, 5).Breast tumors that do not express ER, PgR, or Her2 (ER− PgR− Her2−), as determined by immunohistochemistry (IHC), are generally referred to as triple negative breast cancers (TNBCs), and they are not candidates for targeted therapies (endocrine therapy or trastuzumab). Although TNBCs account for a relatively small proportion of breast cancer cases (10–15%), they are responsible for a disproportionate number of breast cancer deaths. TNBC tumors form a recognizable prognostic group of breast cancer with aggressive behavior that currently lacks the benefit of available systemic therapy (6–8). Given the need to develop molecular criteria to reproducibly categorize molecular breast tumor subtypes at the protein level and the lack of targeted therapies available to treat patients bearing TNBCs, we have implemented a systematic proteomics approach to identify, characterize, and evaluate proteins present in triple-negative tumors that could constitute an appropriate therapeutic target for the clinical management of this group of patients. To this end, based on the analysis of 78 individual TNBC samples, we have established a large, cumulative, 2D-PAGE database of proteins expressed by TNBCs, including some that could be of potential therapeutic value. Comparison of this TNBC protein database with protein databases of other breast cancer subtypes previously established by our laboratory allowed us to single out a number of proteins preferentially expressed in TNBCs for which targeted therapeutics exist. In this report we further focused on the characterization of one such target, the cancer/testis antigen, melanoma-associated antigen 4 - Mage-A4.Cancer/testis antigens (CTAs) are expressed in a large variety of tumor types, whereas their expression in normal tissues is restricted to male germ cells, which are immune-privileged because of their lack of or low expression of human leukocyte antigen (HLA) molecules (9). Several studies have shown the existence of natural cellular and humoral responses against some CTAs, indicating that they are appropriate targets for vaccine-based cancer immunotherapy (10–12). So far, the use of CTAs in immunotherapeutic approaches to cancer treatment has been tested in more than 60 early phase clinical trials, with varying success, and a few candidate products have reached late-stage clinical trials. One such candidate vaccine, Astuprotimut-R (GSK-249553), a Mage-A3 antigen-specific cancer immunotherapeutic agent, is currently under clinical evaluation by GlaxoSmithKline in the largest-ever treatment trial in lung cancer, called MAGRIT (Mage-A3 as Adjuvant nonsmall cell lunG canceR ImmunoTherapy) (13).At present, CTAs comprise about 150 members, more than half of which are encoded by large, recently expanded families on chromosome X (14; see also CTDatabase at www.cta.lncc.br; last accessed 01.09.2012). These genes are organized into clusters and have undergone rapid evolution, possibly because of positive selection. The biological functions of CTAs are not fully understood, but emerging evidence suggest that they direct the proliferation, differentiation, and survival of human germ line cells and may have similar effect in cancer cells. Mage-A4 protein belongs to the Mage-A family of CT antigens. The Mage-A family is composed by 12 proteins (14, 15) and many members of the Mage-A family of CTAs have been associated with cancer, including breast cancer (14, 16, 17). However, past studies reported mostly on MAGE genes rather than protein expression, or on the expression of Mage protein families and not on any given specific protein.In this paper we describe the identification of Mage-A4 in breast tumor biopsies using 2D PAGE coupled with MS proteomics, and follow the protein localization from the tumor cells, to the tumor microenvironment, and to the serum of a patient. Using a three-tier orthogonal technology approach that combined 2D PAGE silver staining coupled with MS, with 2D Western blotting, and IHC, we showed that high level Mage-A4 expression in breast tumors occurs almost exclusively in the receptor negative disease (TNBC and Her2+ER−PgR−). The existence of immunotherapeutic approaches targeting MAGE protein family members (Mage-A4 specific or with broader specificity) and the fact that we were able to detect its presence in serum suggest novel management options for patients bearing Mage-A4 positive TNBCs and Her2+ER−PgR− tumors. 相似文献
64.
65.
Lineage-specific expression of c-fos and c-fms in human hematopoietic cells: Discrepancies with the in vitro differentiation of leukemia cells 总被引:2,自引:0,他引:2
Hans Kreipe Heinz J. Radzun Klaus Heidorn Mohammad Reza Parwaresch Bernard Verrier Rolf Müller 《Differentiation; research in biological diversity》1986,33(1):56-60
In vitro differentiation studies using the bipotential human leukemia cell line, HL60, have indicated that high levels of expression of two proto-oncogenes, c-fos and c-fms, are restricted to the myelomonocytic lineage. No such expression has been detected in induced granulocytic cells. In striking contrast to these observations, we found that c-fos mRNA levels are very high in purified human granulocytes, but barely detectable in blood monocytes and tissue macrophages. Human granulocytes contain, however, relatively low levels of c-fos protein, indicating that c-fos mRNA is inefficiently translated or that the protein is rapidly degraded in these cells. In closer agreement with the in vitro results, the level of the expression of c-fms is high in purified blood monocytes and undetectable in granulocytes. We found, however, that the evolution of monocytes into tissue macrophages is accompanied by a significant decrease in c-fms expression, suggesting that the function of c-fms is restricted to specific stages of monocytic differentiation. Our observations also show that results obtained using in vitro differentiation systems have to be regarded with caution, since they may not reflect the in vivo situation. 相似文献
66.
Reza A. Ghiladi Hong-wei Huang Pierre Moënne-Loccoz Jay Stasser Ninian J. Blackburn Amina S. Woods Robert J. Cotter Christopher D. Incarvito Arnold L. Rheingold Kenneth D. Karlin 《Journal of biological inorganic chemistry》2005,10(1):63-77
In the further development and understanding of heme-copper dioxygen reactivity relevant to cytochrome c oxidase O(2)-reduction chemistry, we describe a high-spin, five-coordinate dioxygen (peroxo) adduct of an iron(II)-copper(I) complex, [((6)L)Fe(II)Cu(I)](BArF(20)) (1), where (6)L is a tetraarylporphyrinate with a tethered tris(2-pyridylmethyl)amine chelate for copper. Reaction of 1 with O(2) in MeCN affords a remarkably stable [t(1/2) (rt; MeCN) approximately 60 min] adduct, [((6)L)Fe(III)-(O(2) (2-))-Cu(II)](+) (2) [EPR silent; lambda(max)=418 (Soret), 561 nm], formulated as a peroxo complex based on manometry (1:O(2)=1:1; spectrophotometric titration, -40 degrees C, MeCN), mass spectrometry {MALDI-TOF-MS: (16)O(2), m/z 1191 ([((6)L)Fe(III)-((16)O(2) (2-))-Cu(II)](+)); (18)O(2), m/z 1195}, and resonance Raman spectroscopy (nu((O-O))=788 cm(-1); Delta(16)O(2)/(18)O(2)=44 cm(-1); Delta(16)O(2)/(16/18)O(2)=22 cm(-1)). (1)H and (2)H NMR spectroscopy (-40 degrees C, MeCN) reveals that 2 is the first heme-copper peroxo complex which is high-spin, with downfield-shifted pyrrole resonances (delta(pyrrole)=75 ppm, s, br) and upfield shifted peaks at delta= -22, -35, and -40 ppm, similar to the pattern observed for the mu-oxo complex [((6)L)Fe(III)-O-Cu(II)](BAr(F)) (3) (known S=2 system, antiferromagnetically coupled high-spin Fe(III) and Cu(II)). The corresponding magnetic moment measurement (Evans method, CD(3)CN, -40 degrees C) also confirms the S=2 spin state, with mu(B)=4.9. Structural insights were obtained from X-ray absorption spectroscopy, showing Fe-O (1.83 A) and Cu-O (1.882 A) bonds, and an Fe...Cu distance of 3.35(2) A, suggestive of a mu-1,2-peroxo ligand present in 2. The reaction of 2 with cobaltocene gives 3, differing from the observed full reduction seen with other heme-Cu peroxo complexes. Finally, thermal decomposition of 2 yields 3, with concomitant release of 0.5 mol O(2) per mol 2, as confirmed quantitatively by an alkaline pyrogallol dioxygen scavenging solution. 相似文献
67.
rafiei Ali Khodabakhsh Farnaz Cohan Reza Ahangari Azadegan-Dehkordi Fatemeh Salimian Morteza 《Molecular biology reports》2022,49(5):3389-3399
Molecular Biology Reports - Aberrant expression of long non-coding RNAs (lncRNAs) can contribute to the pathogenesis of coronary artery disease (CAD). In this study, we aimed to evaluate the... 相似文献
68.
Nazila Danesh Zahra Navaee Sedighi Sima Beigoli Atena Sharifi-Rad Mohammad Reza Saberi 《Journal of biomolecular structure & dynamics》2018,36(7):1747-1763
The interactions between estradiol and two carrier proteins, i.e. human serum albumin (HSA) and holo-transferrin (HTF) in aqueous solution at pH = 7.4 were studied by three-dimensional fluorescence emission spectroscopy, isothermal titration calorimetry (ITC), zeta-potential, resonance light-scattering and molecular modeling. Extensive fluorescence quenching was observed throughout the interaction between the drug and both proteins. Moreover, conformational changes were determined by observing the rearrangement of Trp residues during binding of estradiol with HSA and HTF at different concentrations. ITC experiments revealed that, in the presence of estradiol, both van der Waals forces and hydrogen bonding became predominant. In addition, other binding parameters such as enthalpy and entropy changes were determined by the zeta potential method. Molecular modeling suggested that estradiol was situated within sub-domain IB sited in the hydrophobic cluster in Site I, whereas the drug was located in the N-terminal of HTF where it was hydrogen bonded with Ala 670. 相似文献
69.
70.
Aghamohamadi Elham Asri † Nastaran Odak Aylin Rostami-Nejad Mohammad Chaleshi Vahid Hajinabi Yasaman Eslami Maryam Mohammadian Haftcheshmeh Saeed Gholam-Mostafaei Fahimeh Sadat Asadzadeh-Aghdaei Hamid Masotti Andrea Zali Mohammad Reza 《Molecular biology reports》2022,49(7):6085-6091
Molecular Biology Reports - Celiac disease (CeD) and inflammatory bowel disease (IBD) are accompanied by impaired immune responses. To study the immune regulation of these diseases, we evaluated... 相似文献