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1.
Environ Res ; 259: 119521, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38960350

RESUMO

Tetracycline (TC) and ciprofloxacin (CF) induce a synergistic effect that alters the biochemical composition, leading to a decrease in the growth and photosynthetic efficiency of microalgae. But the current study provides a novel insight into stress-inducing techniques that trigger a change in macromolecules, leading to an increase in the bioenergy potential and pathogen resistance of Chlorella variabilis biofilm. The study revealed that in a closed system, a light intensity of 167 µmol/m2/s causes 93.5% degradation of TC and 16% degradation of CF after 7 days of exposure, hence availing the products for utilization by C. variabilis biofilm. The resistance to pathogens invasion was linked to 85% and 40% increase in the expression level of photosystem II oxygen-evolving enhancer protein 3 (PsbQ), and mitogen activated kinase (MAK) respectively. The results also indicate that a surge in light intensity triggers 49% increase in the expression level of lysophosphatidylcholine (LPC) (18:2), which is an important lipidomics that can easily undergo transesterification into bioenergy. The thermogravimetric result indicates that the biomass sample of C. variabilis biofilm cultivated under light intensity of 167 µmol/m2/s produces a higher residual mass of 45.5% and 57.5 under air and inert conditions, respectively. The Fourier transform infrared (FTIR) indicates a slight shift in the major functional groups, while the energy-dispersive X-ray spectroscopy (SEM-EDS) and X-ray fluorescence (XRF) indicate clear differences in the morphology and elemental composition of the biofilm biomass in support of the increase bioenergy potential of C. variabilis biofilm. The current study provides a vital understanding of a innovative method of cultivation of C. variabilis biofilm, which is resistant to pathogens and controls the balance between fatty acid and TAG synthesis leading to surge in bioenergy potential and environmental sustainability.

2.
Arch Med Sci ; 19(2): 523-527, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37034522

RESUMO

Introduction: This study aimed to define and update the prevalence of ß-pathogenic thalassemia variants in Jordan. Methods: A total of 158 patients with suspected ß-thalassemia minor were examined using CBC and Hb-electrophoresis, and polymerase chain reaction with hybridization to identify the type of pathogenic variants. Results: Five common and seven rare ß-thalassemia pathogenic variants were identified in this study, in addition to three variants that had not been previously reported: -101 [C>T], IVS 1.130 [G>C], and codon 44 [-C]. Conclusions: The results provide a new update on the existing Jordanian ß-thalassemia variant database that will aid the enhancement of diagnostic and treatment protocols for patients.

4.
Asian Pac J Cancer Prev ; 22(10): 3355-3363, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34711013

RESUMO

OBJECTIVE: This study aimed to investigate level fluctuations of serum biomarkers that are associated with cardiotoxicity risk, such as high-sensitivity C-reactive protein (hs-CRP) and apolipoprotein-B (Apo-B) in response to chemotherapy treatment for breast cancer. METHOD: The serum levels of hs-CRP and Apo-B were evaluated in 56 breast cancer patients with main inclusion criteria: HER2 negative and who received adjuvant chemotherapy AC [A: Adriamycin, C: Cyclophosphamide] or AC→T [A: Adriamycin, C: Cyclophosphamide, T: Taxane] regimes at early II (n = 26) and late IV (n = 30) clinical stages by using particle enhanced turbidimetric assay. RESULTS: The results of this study suggest that a high level of pre-treatment hs-CRP is a good prognostic marker in comparison to Apo-B. Moreover, the AC-T chemotherapy regime treatment in both early and late stages exhibited a significantly higher level of hs-CRP compared to that in the AC regime. Hs-CRP was significantly elevated in the early stage in comparison to the late stage among cancer patients, meanwhile Apo-B behaved inversely. Furthermore, the results showed that hs-CRP levels were significantly higher in late-stage cancer patients compared with those in early-stage in both chemotherapy regimens groups. On the other hand, Apo-B showed no significant differences. CONCLUSION: Monitoring hs-CRP level changes in comparison to Apo-B can be used to assist the side effect risk difference among different chemotherapy regimens, and staging reflecting a positive correlation between them more notable in the late stage.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Apolipoproteínas B/sangue , Neoplasias da Mama/sangue , Proteína C-Reativa/metabolismo , Cardiotoxicidade/diagnóstico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores/sangue , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Hidrocarbonetos Aromáticos com Pontes/administração & dosagem , Hidrocarbonetos Aromáticos com Pontes/efeitos adversos , Cardiotoxicidade/etiologia , Quimioterapia Adjuvante/efeitos adversos , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade , Medição de Risco , Taxoides/administração & dosagem , Taxoides/efeitos adversos
5.
Int J Phytoremediation ; 23(11): 1175-1183, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33563031

RESUMO

This study aimed at studying the phycoremediation of petroleum-contaminated water using microalgae biofilm cultured in nutrient-rich water. Microalgae biofilm was grown in a photobioreactor containing water rich in calcium nitrate, manganese chloride, sodium potassium tartrate, calcium phosphate, and ammonium sulfate. Petroleum contaminated water was poured into a photobioreactor, and the substrate containing microalgae biofilm was inserted into the photobioreactor and allowed for eight weeks for biofilm formation. Physicochemical parameters (pH, turbidity, conductivity, sulfate, alkalinity, chloride, TDS, TSS, nitrate, salinity, iron, potassium, phosphate, chlorine, chromium, magnesium, zinc, COD, BOD, and total petroleum hydrocarbon (TPH) of the petroleum contaminated water before and after treatment were determined. The microalgae biofilm used for the treatment was characterized before and after treatment using a Scanning Electron Microscope, X-Ray Fluorescence, and Fourier-transform infrared spectroscopy. The phytochemical constituent of the microalgae biofilm was also determined before and after treatment of the petroleum-contaminated water. The result obtained shows highest removal efficiency of physicochemical parameters (turbidity (81%), conductivity (51.2), sulfate (17.5%), alkalinity 28.4%), chloride (14.6%), TDS (7.9), TSS (26%), nitrate (33%), salinity (23.4), iron (16%), potassium (22%), phosphate (28.2%), chlorine (14%), chromium (13.6%), magnesium (30.3%), zinc (40.5%), COD (8%), BOD (16.7%) and total petroleum hydrocarbon (15%)). The microalgae's characterization shows microalgae biofilm's ability to adsorb pollutants in petroleum-contaminated water due to the presence of microspores and larger surface area of the cells of the microalgae forming the biofilm or due to the absorption efficiency of the extracellular polymeric substances (EPS). The analysis of the microalgae biofilm's phytochemical parameters shows the involvement of the chemicals components in pollutants degradation and antioxidant response of the microalgae to counteract the oxidative effect resulting from the exposure of the microalgae to the contaminated water. NOVELTY STATEMENT This is the first study that attempts the phycoremediation of petroleum contaminated water using microalgae biofilm. The reduction efficiency of the parameters treated in this study is very low compared to that reported in the literature but increases with the retention day. This low reduction efficiency is attributed to the slow assimilation of organic and inorganic pollutants due to the initial growth condition. This study is the first to re-affirm that microalgae biofilm can phycoremediate petroleum-contaminated water by adsorption and assimilation due to the presence of microspores and a larger surface area the cells of the microalgae forming the biofilm or the extracellular polymetric surface covering the biofilm. Several studies have reported that phytochemicals present in microalgae play an antioxidant response role to prevent the microalgae from oxidative damage resulting from water pollution. However, this study is the first to strongly link phytochemicals to the enhancement of pollutants degradation and adsorption by microalgae biofilm.


Assuntos
Microalgas , Petróleo , Biodegradação Ambiental , Biofilmes , Nutrientes , Água , Poluição da Água
6.
PLoS One ; 13(9): e0203745, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30216369

RESUMO

Prostate cancer (PCA) is one of the most common cancer types in men, with cancer progression being linked to hypoxia and the induction of hypoxia-inducible factor (HIF).We investigated the expression of pyruvate kinase M2 (PKM2), its regulation by HIF isoforms 1α and 2α, and its role in HIF stabilization. We additionally examined cell survival in the prostate cancer cell lines PC3 and LNCaP under severe hypoxic (0.1% O2) and normoxic (20% O2) conditions. qRT-PCR showed higher up-regulation of PKM2 mRNA expression in LNCaP cells than in PC3 cells, while western blotting showed that PKM2 protein levels were up-regulated only in LNCaP cells. Inhibition of HIF-1α and HIF-2α by small interfering RNA (si-RNA) demonstrated HIF-1α dependent up-regulation of PKM2 at the mRNA and protein levels in LNCaP cells. PKM2 inhibition by si-RNA significantly decreased hypoxia-response element (HRE) activation in a gene reporter assay and down-regulated HIF-1α target vascular endothelial growth factor (VEGF) mRNA expression in PC3 cells, whereas HIF-1α protein levels were not significantly reduced. Additionally, PKM2 inhibition significantly reduced clonogenic survival in both cell lines in a colony formation assay. Prolyl hydroxylase 3 (PHD3) mRNA expression was up-regulated in both cell lines. It has been shown that PKM2 expression is regulated by HIF-1α and that PKM2 favors HIF-1α transactivation under mild (1% O2) but not severe (0.1% O2) hypoxic conditions, and some of our findings are consistent with these previous results. However, this mechanism was not fully observed in our studied cell lines, as PKM2 regulation and HIF-1α stabilization at the transactivation level occurred under severe hypoxic conditions. This discrepancy suggests that tumor tissue origin and cell type influence this model. Our findings expand the current knowledge of the mechanisms of PCA regulation, and would be important in developing novel therapeutic strategies.


Assuntos
Proteínas de Transporte/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Proteínas de Membrana/genética , Neoplasias da Próstata/genética , Hormônios Tireóideos/genética , Proteínas de Transporte/metabolismo , Hipóxia Celular , Linhagem Celular Tumoral , Proliferação de Células/genética , Sobrevivência Celular , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Células PC-3 , Neoplasias da Próstata/metabolismo , Interferência de RNA , Hormônios Tireóideos/metabolismo , Proteínas de Ligação a Hormônio da Tireoide
7.
Cell Res ; 25(7): 837-50, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26045162

RESUMO

The eukaryotic genome is organized into chromatins, the physiological template for DNA-dependent processes including replication, recombination, repair, and transcription. Chromatin-mediated transcription regulation involves DNA methylation, chromatin remodeling, and histone modifications. However, chromatin also contains non-histone chromatin-associated proteins, of which the high-mobility group (HMG) proteins are the most abundant. Although it is known that HMG proteins induce structural changes of chromatin, the processes underlying transcription regulation by HMG proteins are poorly understood. Here we decipher the molecular mechanism of transcription regulation mediated by the HMG AT-hook 2 protein (HMGA2). We combined proteomic, ChIP-seq, and transcriptome data to show that HMGA2-induced transcription requires phosphorylation of the histone variant H2AX at S139 (H2AXS139ph; γ-H2AX) mediated by the protein kinase ataxia telangiectasia mutated (ATM). Furthermore, we demonstrate the biological relevance of this mechanism within the context of TGFß1 signaling. The interplay between HMGA2, ATM, and H2AX is a novel mechanism of transcription initiation. Our results link H2AXS139ph to transcription, assigning a new function for this DNA damage marker. Controlled chromatin opening during transcription may involve intermediates with DNA breaks that may require mechanisms that ensure the integrity of the genome.


Assuntos
Dano ao DNA/fisiologia , Reparo do DNA/fisiologia , Proteínas de Grupo de Alta Mobilidade/metabolismo , Histonas/metabolismo , Animais , Proteínas de Ciclo Celular/metabolismo , Montagem e Desmontagem da Cromatina/fisiologia , Replicação do DNA/fisiologia , Humanos , Camundongos , Proteômica/métodos , Transdução de Sinais/fisiologia
8.
ScientificWorldJournal ; 2014: 252491, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24592152

RESUMO

The mineralisation kinetics of petroleum refinery effluent (PRE) by Fenton oxidation were evaluated. Within the ambit of the experimental data generated, first-order kinetic model (FKM), generalised lumped kinetic model (GLKM), and generalized kinetic model (GKM) were tested. The obtained apparent kinetic rate constants for the initial oxidation step (k'2), their final oxidation step (k'1), and the direct conversion to endproducts step (k3') were 10.12, 3.78, and 0.24 min(-1) for GKM; 0.98, 0.98, and nil min(-1) for GLKM; and nil, nil, and >0.005 min(-1) for FKM. The findings showed that GKM is superior in estimating the mineralization kinetics.


Assuntos
Peróxido de Hidrogênio/química , Ferro/química , Modelos Químicos , Petróleo , Águas Residuárias/química , Cinética , Oxirredução
9.
J Proteome Res ; 12(12): 5598-608, 2013 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-24175614

RESUMO

Alveolar type-II cells (ATII cells) are lung progenitor cells responsible for regeneration of alveolar epithelium during homeostatic turnover and in response to injury. Characterization of ATII cells will have a profound impact on our understanding and treatment of lung disease. The identification of novel ATII cell-surface proteins can be used for sorting and enrichment of these cells for further characterization. Here we combined a high-resolution mass spectrometry-based membrane proteomic approach using lungs of the SILAC mice with an Affymetrix microarray-based transcriptome analysis of ATII cells. We identified 16 proteins that are enriched in the membrane fraction of ATII cells and whose genes are highly expressed in these cells. Interestingly, we confirmed our data for two of these genes, integrin beta 2 and 6 (Itgb2 and Itgb6), by qRT-PCR expression analysis and Western blot analysis of protein extracts. Moreover, flow cytometry and immunohistochemistry in adult lung revealed that ITGB2 and ITGB6 are present in subpopulations of surfactant-associated-protein-C-positive cells, suggesting the existence of different types of ATII cells. Furthermore, analysis of the Itgb2(-/-) mice showed that Itgb2 is required for proper WNT signaling regulation in the lung.


Assuntos
Antígenos CD18/genética , Células Epiteliais/metabolismo , Cadeias beta de Integrinas/genética , Proteoma/genética , Células-Tronco/citologia , Células-Tronco/metabolismo , Via de Sinalização Wnt/genética , Animais , Antígenos CD18/metabolismo , Membrana Celular/química , Membrana Celular/metabolismo , Células Epiteliais/citologia , Regulação da Expressão Gênica , Cadeias beta de Integrinas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Anotação de Sequência Molecular , Ligação Proteica , Proteína C/genética , Proteína C/metabolismo , Proteoma/metabolismo , Alvéolos Pulmonares/citologia , Alvéolos Pulmonares/metabolismo , Mucosa Respiratória/citologia , Mucosa Respiratória/metabolismo , Análise Serial de Tecidos
10.
Environ Technol ; 33(10-12): 1111-21, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22856280

RESUMO

The mineralisation of remazol black B (RBB) was studied at concentrations ranging from 20-1000 mgL(-1). The work was aimed at investigating the Fenton-like peroxidation of RBB at a concentration typically obtained in Batik cottage industries. Other response parameters were degradation and colour removal efficiencies. The parameters that were measured included total organic carbon (TOC), chemical oxygen demand (COD) as well as absorbance for mineralisation, degradation and colour. To optimise the process, the interaction effects of several controlling variables on the treatment process were examined using dispersion matrix-optimal design and response surface analysis. Four specific variables: initial dye concentration (Dye)o; the molar ratio of oxidant to dye organic strength (H2O2):(COD); the mass ratio of the oxidant to the catalyst (H2O2):(Fe3+) and reaction time (t(r)), were observed. Three reduced empirical models, one for each response, were developed for describing the treatment process. For 20, 510 and 1000 mgL(-1), the optimum %TOC reduction and oxidation times were 44% for 95 min, 52% for 52.5 min and 68% for 10 min corresponding to 67, 81 and 75% COD reduction, respectively. The optimum COD reduction and oxidation times were 89% for 95 min, 91% for 10 min and 84% for 95 min for concentrations of 20, 510 and 1000 mg L(-1), respectively. For all concentrations, total colour removal was achieved. A comparison of the results obtained in this study with literature values for traditional Fenton, photo-Fenton and photo-Fenton-like oxidation indicated that the TOC reduction obtained using the Fenton-like process was satisfactory.


Assuntos
Peróxido de Hidrogênio/química , Ferro/química , Modelos Químicos , Naftalenossulfonatos/química , Análise da Demanda Biológica de Oxigênio , Oxirredução
11.
Int J Radiat Oncol Biol Phys ; 80(5): 1541-9, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21621345

RESUMO

PURPOSE: Radiotherapy resistance is a commonly encountered problem in cancer treatment. In this regard, stabilization of endothelial cells and release of angiogenic factors by cancer cells contribute to this problem. In this study, we used human lung adenocarcinoma (A549) cells to compare the effects of carbon ion and X-ray irradiation on the cells' angiogenic response. METHODS AND MATERIALS: A549 cells were irradiated with biologically equivalent doses for cell survival of either carbon ions (linear energy transfer, 170 keV/µm; energy of 9.8 MeV/u on target) or X-rays and injected with basement membrane matrix into BALB/c nu/nu mice to generate a plug, allowing quantification of angiogenesis by blood vessel enumeration. The expression of angiogenic factors (VEGF, PlGF, SDF-1, and SCF) was assessed at the mRNA and secreted protein levels by using real-time reverse transcription-PCR and enzyme-linked immunosorbent assay. Signal transduction mediated by stem cell factor (SCF) was assessed by phosphorylation of its receptor c-Kit. For inhibition of SCF/c-Kit signaling, a specific SCF/c-Kit inhibitor (ISCK03) was used. RESULTS: Irradiation of A549 cells with X-rays (6 Gy) but not carbon ions (2 Gy) resulted in a significant increase in blood vessel density (control, 20.71 ± 1.55; X-ray, 36.44 ± 3.44; carbon ion, 16.33 ± 1.03; number per microscopic field). Concordantly, irradiation with X-rays but not with carbon ions increased the expression of SCF and subsequently caused phosphorylation of c-Kit in endothelial cells. ISCK03 treatment of A549 cells irradiated with X-rays (6 Gy) resulted in a significant decrease in blood vessel density (X-ray, 36.44 ± 3.44; X-ray and ISCK03, 4.33 ± 0.71; number of microscopic field). These data indicate that irradiation of A549 cells with X-rays but not with carbon ions promotes angiogenesis. CONCLUSIONS: The present study provides evidence that SCF is an X-ray-induced mediator of angiogenesis in A549 cells, a phenomenon that could not be observed with carbon ion irradiation. Thus, in this model system evaluating angiogenesis, carbon ion irradiation may have a therapeutic advantage. This observation should be confirmed in orthotopic lung tumor models.


Assuntos
Adenocarcinoma/irrigação sanguínea , Adenocarcinoma/radioterapia , Carbono/uso terapêutico , Radioterapia com Íons Pesados , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/radioterapia , Neovascularização Patológica/etiologia , Fótons/uso terapêutico , Adenocarcinoma/metabolismo , Adenocarcinoma de Pulmão , Animais , Carcinoma Pulmonar de Células não Pequenas/irrigação sanguínea , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos da radiação , Quimiocina CXCL12/metabolismo , Humanos , Imidazóis/farmacologia , Transferência Linear de Energia , Neoplasias Pulmonares/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Nus , Proteínas de Neoplasias/metabolismo , Neovascularização Patológica/metabolismo , Neovascularização Patológica/fisiopatologia , Fosforilação , Proteínas Proto-Oncogênicas c-kit/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-kit/metabolismo , Fator de Células-Tronco/antagonistas & inibidores , Fator de Células-Tronco/metabolismo , Sulfonamidas/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
12.
J Mol Cell Biol ; 2(6): 345-56, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20980400

RESUMO

T-cell intracellular antigen (TIA)-1 and TIA-1-related protein (TIAR) are mRNA-binding proteins that can aggregate within granules under specific stress conditions. In this study, we analyzed TIAR/TIA-1 aggregation under different hypoxic conditions, and studied the effects on the hypoxia-inducible factor (HIF)-1α in different cancer cell lines. Under acute and pronounced hypoxic conditions TIAR/TIA-1 co-aggregated to granules and positive co-staining with eIF3η marker suggested these to represent stress granules. In parallel, HIF-1α expression was blocked in cells displaying TIAR/TIA-1 granules. Silencing of TIAR and TIA-1 caused upregulation of HIF-1α expression, as demonstrated by western blot, immunocytochemistry and HIF-1-dependent reporter gene expression. Additionally, a critical region of the 3' end of the untranslated HIF-1α mRNA with possible adenosine-uridine-rich elements (AREs) was coupled to the luciferase reporter gene, causing downregulation of expression. Employing this reporter construct, inhibition of TIAR by siRNA attenuated the inhibitory cis-effect of this ARE-sequence. Furthermore, immunohistochemical analysis of A549 cell tumor xenografts revealed a nearly complementary expression of HIF-1α and TIAR reflecting the control of HIF-1α expression by TIAR as revealed in the cell culture studies. In sum, rapid and severe hypoxia caused co-aggregation of TIAR/TIA-1 and these proteins suppressed HIF-1α expression.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Oxigênio/metabolismo , Proteínas de Ligação a Poli(A)/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Hipóxia Celular , Linhagem Celular Tumoral , Fator de Iniciação 3 em Eucariotos/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Camundongos , Proteínas de Ligação a Poli(A)/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Proteínas de Ligação a RNA/genética , Antígeno-1 Intracelular de Células T , Transplante Heterólogo
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