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1.
J Trop Pediatr ; 66(6): 569-582, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32577754

RESUMO

OBJECTIVES: This study aimed to determine whether maternal-fetal blood group isoimmunization, breastfeeding, birth trauma, age when first total serum bilirubin (TSB) was measured, age of admission, and genetic predispositions to hemolysis [due to genetic variants of glucose-6-phosphate dehydrogenase (G6PD) enzyme], and reduced hepatic uptake and/or conjugation of serum bilirubin [due to genetic variants of solute carrier organic anion transporter protein family member 1B1 (SLCO1B1) and uridine diphosphate glucuronosyltransferase family 1 member A1 (UGT1A1)] were significant risk factors associated with severe neonatal hyperbilirubinemia (SNH, TSB ≥ 342µmol/l) in jaundiced term neonates admitted for phototherapy. METHODS: The inclusion criteria were normal term neonates (gestation ≥ 37 weeks). Parents/care-givers were interviewed to obtain data on demography, clinical problems, feeding practice and age when first TSB was measured. Polymerase chain reaction-restriction fragment length polymorphism method was used to detect common G6PD, UGT1A1 and SLCO1B1 variants on each neonate's dry blood specimens. RESULTS: Of 1121 jaundiced neonates recruited, 232 had SNH. Logistic regression analysis showed that age (in days) when first TSB was measured [adjusted odds ratio (aOR) = 1.395; 95% confidence interval (CI) 1.094-1.779], age (in days) of admission (aOR = 1.127; 95% CI 1.007-1.260) and genetic mutant UGT1A1 promoter A(TA)7TAA (aOR = 4.900; 95% CI 3.103-7.739), UGT1A1 c.686C>A (aOR = 6.095; 95% CI 1.549-23.985), SLCO1B1 c.388G>A (aOR = 1.807; 95% CI 1.242-2.629) and G6PD variants and/or abnormal G6PD screening test (aOR = 2.077; 95% CI 1.025-4.209) were significantly associated with SNH. CONCLUSION: Genetic predisposition, and delayed measuring first TSB and commencing phototherapy increased risk of SNH.


Assuntos
Bilirrubina/sangue , Glucosefosfato Desidrogenase/genética , Glucuronosiltransferase/genética , Hiperbilirrubinemia Neonatal/genética , Transportador 1 de Ânion Orgânico Específico do Fígado/genética , Fígado/metabolismo , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Glucosefosfato Desidrogenase/metabolismo , Glucuronosiltransferase/metabolismo , Humanos , Hiperbilirrubinemia Neonatal/diagnóstico , Hiperbilirrubinemia Neonatal/terapia , Recém-Nascido , Icterícia , Transportador 1 de Ânion Orgânico Específico do Fígado/metabolismo , Masculino , Fototerapia
2.
Cancer Cell Int ; 17: 30, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28239299

RESUMO

AIMS: Curcumin is a lead compound of the rhizomes of Curcuma longa and possess a broad range of pharmacological activities. Chemically, curcumin is 1,3-dicarbonyl class of compound, which exhibits keto-enol tautomerism. Despite of its strong biological properties, curcumin has yet been recommended as a therapeutic agent because of its poor bioavailability. MAIN METHODS: A curcumin derivative (Z)-3-hydroxy-1-(2-hydroxyphenyl)-3-phenylprop-2-en-1-one (DK1) was synthesized and its cytotoxicity was tested on breast cancer cell MCF-7 and normal cell MCF-10A using MTT assay. Meanwhile, cell cycle regulation and apoptosis on MCF-7 cell were evaluated using flow cytometry. Regulation of cell cycle and apoptosis related genes expression was investigated by quantitative real time polymerase chain reaction (qRT-PCR), western blot and caspases activity analyses. Activation of oxidative stress on MCF-7 were evaluated by measuring ROS and GSH levels. KEY FINDINGS: DK1 was found to possess selective cytotoxicity on breast cancer MCF-7 cell than normal MCF-10A cell. Flow cytometry cell cycle and AnnexinV/PI analyses reported that DK1 effectively arrested MCF-7 at G2/M phase and induced apoptosis after 72 h of incubation than curcumin. Upregulation of p53, p21 and downregulation of PLK-1 subsequently promote phosphorylation of CDC2 which were found contributed to the arrest of G2/M phase. Moreover, increased of reactive oxygen species and reduced of antioxidant glutathione level correlate with apoptosis observed with raised of cytochrome c and active caspase 9. SIGNIFICANCE: DK1 was found to be more effective in inducing cell cycle arrest and apoptosis against MCF-7 cell with much higher selectivity index of MCF-10A/MCF-7 than curcumin, which might be contributed by the overexpression of p53 protein.

3.
Int J Med Sci ; 11(11): 1154-60, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25170299

RESUMO

Four osteosarcoma cell lines, Saos-2, MG-63, G-292 and U-2 OS, were reprogrammed to pluripotent state using Yamanaka factors retroviral transduction method. Embryonic stem cell (ESC)-like clusters started to appear between 15 to 20 days post transduction. Morphology of the colonies resembled that of ESC colonies with defined border and tightly-packed cells. The reprogrammed sarcomas expressed alkaline phosphatase and pluripotency markers, OCT4, SSEA4, TRA-1-60 and TRA-1-81, as in ESC up to Passage 15. All reprogrammed sarcomas could form embryoid body-like spheres when cultured in suspension in a low attachment dish for up to 10 days. Further testing on the directed differentiation capacity of the reprogrammed sarcomas showed all four reprogrammed sarcoma lines could differentiate into adipocytes while reprogrammed Saos-2-REP, MG-63-REP and G-292-REP could differentiate into osteocytes. Among the 4 osteosarcoma cell lines, U-2 OS reported the highest transduction efficiency but recorded the lowest reprogramming stability under long term culture. Thus, there may be intrinsic differences governing the variable responses of osteosarcoma cell lines towards reprogramming and long term culture effect of the reprogrammed cells. This is a first report to associate intrinsic factors in different osteosarcoma cell lines with variable reprogramming responses and effects on the reprogrammed cells after prolonged culture.


Assuntos
Reprogramação Celular/fisiologia , Osteossarcoma/metabolismo , Antígenos de Superfície/genética , Antígenos de Superfície/metabolismo , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Reprogramação Celular/genética , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Humanos , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Osteócitos/citologia , Osteócitos/metabolismo , Osteossarcoma/genética , Proteoglicanas/genética , Proteoglicanas/metabolismo , Antígenos Embrionários Estágio-Específicos/genética , Antígenos Embrionários Estágio-Específicos/metabolismo
4.
Prog Mol Biol Transl Sci ; 199: 131-154, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37678969

RESUMO

Mesenchymal stem cells (MSCs) differentiated from human induced pluripotent stem cells (iPSC) or induced MSC (iMSCs) are expected to address issues of scalability and safety as well as the difficulty in producing homogenous clinical grade MSCs as demonstrated by the promising outcomes from preclinical and clinical trials, currently ongoing. The assessment of iMSCs based in vitro and in vivo studies have thus far showed more superior performance as compared to that of the primary or native human MSCs, in terms of cell proliferation, expansion capacity, immunomodulation properties as well as the influence of paracrine signaling and exosomal influence in cell-cell interaction. In this chapter, an overview of current well-established methods in generating a sustainable source of iMSCs involving well defined culture media is discussed followed by the properties of iMSC as compared to that of MSC and its promising prospects for continuous development into potential clinical grade applications.


Assuntos
Células-Tronco Pluripotentes Induzidas , Humanos , Diferenciação Celular , Proliferação de Células , Imunomodulação , Projetos de Pesquisa
5.
Biometals ; 25(5): 1061-81, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22836829

RESUMO

A series of ternary copper(II)-1,10-phenanthroline complexes with glycine and methylated glycine derivatives, [Cu(phen)(aa)(H(2)O)]NO(3)·xH(2)O 1-4 (amino acid (aa): glycine (gly), 1; DL: -alanine (DL: -ala), 2; 2,2-dimethylglycine (C-dmg), 3; sarcosine (sar), 4), were synthesized and characterized by FTIR, elemental analysis, electrospray ionization-mass spectra (ESI-MS), UV-visible spectroscopy and molar conductivity measurement. The determined X-ray crystallographic structures of 2 and 3 show each to consist of distorted square pyramidal [Cu(phen)(aa)(H(2)O)](+) cation, a nitrate counter anion, and with or without lattice water, similar to previously reported structure of [Cu(phen)(gly)(H(2)O)]NO(3)·1½H(2)O. It is found that 1-4 exist as 1:1 electrolytes in aqueous solution, and the cationic copper(II) complexes are at least stable up to 24 h. Positive-ion ESI-MS spectra show existence of only undissociated [Cu(phen)(aa)](+) species. Electron paramagnetic resonance, gel electrophoresis, fluorescence quenching, and restriction enzyme inhibition assay were used to study the binding interaction, binding affinity and selectivity of these complexes for various types of B-form DNA duplexes and G-quadruplex. All complexes can bind selectively to DNA by intercalation and electrostatic forces, and inhibit topoisomerase I. The effect of the methyl substituents of the coordinated amino acid in the above complexes on these biological properties are presented and discussed. The IC(50) values (24 h) of 1-4 for nasopharyngeal cancer cell line HK1 are in the range 2.2-5.2 µM while the corresponding values for normal cell line NP69 are greater than 13.0 µM. All complexes, at 5 µM, induced 41-60 % apoptotic cell death in HK1 cells but no significant cell death in NP69 cells.


Assuntos
Antineoplásicos/farmacologia , Cobre/farmacologia , Compostos Organometálicos/farmacologia , Animais , Antineoplásicos/química , Linhagem Celular , Linhagem Celular Tumoral , Cobre/química , Cristalografia por Raios X , DNA/química , DNA/efeitos dos fármacos , Espectroscopia de Ressonância de Spin Eletrônica , Glicina/análogos & derivados , Glicina/química , Glicina/farmacologia , Humanos , Ligantes , Masculino , Compostos Organometálicos/química , Espectrometria de Massas por Ionização por Electrospray , Espectroscopia de Infravermelho com Transformada de Fourier , Inibidores da Topoisomerase I/química , Inibidores da Topoisomerase I/farmacologia
6.
J Chin Med Assoc ; 84(6): 563-576, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33883467

RESUMO

Lung cancer is one of the most prevalent human cancers, and single-cell RNA sequencing (scRNA-seq) has been widely used to study human lung cancer at the cellular, genetic, and molecular level. Even though there are published reviews, which summarized the applications of scRNA-seq in human cancers like breast cancer, there is lack of a comprehensive review, which could effectively highlight the broad use of scRNA-seq in studying lung cancer. This review, therefore, was aimed to summarize the various applications of scRNA-seq in human lung cancer research based on the findings from different published in vitro, in vivo, and clinical studies. The review would first briefly outline the concept and principle of scRNA-seq, followed by the discussion on the applications of scRNA-seq in studying human lung cancer. Finally, the challenges faced when using scRNA-seq to study human lung cancer would be discussed, and the potential applications and challenges of scRNA-seq to facilitate the development of personalized cancer therapy in the future would be explored.


Assuntos
Neoplasias Pulmonares/genética , Medicina de Precisão , Análise de Sequência de RNA , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Sequenciamento do Exoma
7.
J Chin Med Assoc ; 83(1): 67-76, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31904742

RESUMO

BACKGROUND: In vitro 3-dimensional (3D) spheroid culture has been widely used as model to enrich CD44CD24 cancer stem cells (CSC) with high aldehyde dehydrogenase 1 (ALDH1) activity. Although CD24 subpopulation was known to be present in 3D spheroids and may influence cancer drug therapies, its characteristics and CSC properties were not well defined. METHODS: In this study, CD24 population from the Michigan Cancer Foundation-7 (MCF-7) spheroid was sorted and subjected to spheroid formation test, stem cell markers immunofluorescence, invasion and migration test, as well as microRNA expression profiling. RESULTS: Sorted MCF-7 CD24 cells from primary spheroids were able to reform its 3D spheroid shape after 7 days in nonadherent culture conditions. In contrast to the primary spheroids, the expression of SOX-2, CD44, CD49f, and Nanog was dim in MCF-7 CD24 cells. Remarkably, MCF-7 CD24 cells were found to show high expression of ALDH1 protein which may have resulted in these cells exhibiting higher resistance against doxorubicin and cisplatin when compared with that of the parental cells. Moreover, microRNA profiling has shown that the absence of CSC properties was consistent with the downregulation of major CSCs-related pathways including Hedgehog, wingless-related integration site (Wnt), and microtubule associated protein kinase (MAPK) signaling pathways. However, the upregulated pathways such as adherens junctions, focal adhesion, and tight junction suggest that CD24 cells were probably at an epithelial-like state of cell transition. CONCLUSION: In conclusion, neglected CD24 cells in MCF-7 spheroid did not exhibit typical breast CSCs properties. The presence of miRNAs and their analyzed pathways suggested that these cells could be a distinct intermediate cell state in breast CSCs.


Assuntos
Neoplasias da Mama/patologia , Antígeno CD24/análise , MicroRNAs/análise , Células-Tronco Neoplásicas/citologia , Esferoides Celulares/citologia , Movimento Celular , Resistencia a Medicamentos Antineoplásicos , Feminino , Imunofluorescência , Humanos , Células MCF-7 , Invasividade Neoplásica , Fenótipo , Transdução de Sinais/fisiologia
8.
Pharmaceuticals (Basel) ; 14(1)2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33374139

RESUMO

Globally, breast cancer is the most frequently diagnosed cancer in women, and it remains a substantial clinical challenge due to cancer relapse. The presence of a subpopulation of dormant breast cancer cells that survived chemotherapy and metastasized to distant organs may contribute to relapse. Tumor microenvironment (TME) plays a significant role as a niche in inducing cancer cells into dormancy as well as involves in the reversible epithelial-to-mesenchymal transition (EMT) into aggressive phenotype responsible for cancer-related mortality in patients. Mesenchymal stem cells (MSCs) are known to migrate to TME and interact with cancer cells via secretion of exosome- containing biomolecules, microRNA. Understanding of interaction between MSCs and cancer cells via exosomal miRNAs is important in determining the therapeutic role of MSC in treating breast cancer cells and relapse. In this study, exosomes were harvested from a medium of indirect co-culture of MCF7-luminal and MDA-MB-231-basal breast cancer cells (BCCs) subtypes with adipose MSCs. The interaction resulted in different exosomal miRNAs profiles that modulate essential signaling pathways and cell cycle arrest into dormancy via inhibition of metastasis and epithelial-to-mesenchymal transition (EMT). Overall, breast cancer cells displayed a change towards a more dormant-epithelial phenotype associated with lower rates of metastasis and higher chemoresistance. The study highlights the crucial roles of adipose MSCs in inducing dormancy and identifying miRNAs-dormancy related markers that could be used to identify the metastatic pattern, predict relapses in cancer patients and to be potential candidate targets for new targeted therapy.

9.
PeerJ ; 5: e3551, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28717596

RESUMO

Breast cancer spheroids have been widely used as in vitro models of cancer stem cells (CSCs), yet little is known about their phenotypic characteristics and microRNAs (miRNAs) expression profiles. The objectives of this research were to evaluate the phenotypic characteristics of MDA-MB-231 spheroid-enriched cells for their CSCs properties and also to determine their miRNAs expression profile. Similar to our previously published MCF-7 spheroid, MDA-MB-231 spheroid also showed typical CSCs characteristics namely self-renewability, expression of putative CSCs-related surface markers and enhancement of drug resistance. From the miRNA profile, miR-15b, miR-34a, miR-148a, miR-628 and miR-196b were shown to be involved in CSCs-associated signalling pathways in both models of spheroids, which highlights the involvement of these miRNAs in maintaining the CSCs features. In addition, unique clusters of miRNAs namely miR-205, miR-181a and miR-204 were found in basal-like spheroid whereas miR-125, miR-760, miR-30c and miR-136 were identified in luminal-like spheroid. Our results highlight the roles of miRNAs as well as novel perspectives of the relevant pathways underlying spheroid-enriched CSCs in breast cancer.

10.
PeerJ ; 4: e1536, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26788424

RESUMO

Decline in the therapeutic potential of bone marrow-derived mesenchymal stem cells (MSC) is often seen with older donors as compared to young. Although hypoxia is known as an approach to improve the therapeutic potential of MSC in term of cell proliferation and differentiation capacity, its effects on MSC from aged donors have not been well studied. To evaluate the influence of hypoxia on different age groups, MSC from young (<30 years) and aged (>60 years) donors were expanded under hypoxic (5% O2) and normal (20% O2) culture conditions. MSC from old donors exhibited a reduction in proliferation rate and differentiation potential together with the accumulation of senescence features compared to that of young donors. However, MSC cultured under hypoxic condition showed enhanced self-renewing and proliferation capacity in both age groups as compared to normal condition. Bioinformatic analysis of the gene ontology (GO) and KEGG pathway under hypoxic culture condition identified hypoxia-inducible miRNAs that were found to target transcriptional activity leading to enhanced cell proliferation, migration as well as decrease in growth arrest and apoptosis through the activation of multiple signaling pathways. Overall, differentially expressed miRNA provided additional information to describe the biological changes of young and aged MSCs expansion under hypoxic culture condition at the molecular level. Based on our findings, the therapeutic potential hierarchy of MSC according to donor's age group and culture conditions can be categorized in the following order: young (hypoxia) > young (normoxia) > old aged (hypoxia) > old aged (normoxia).

11.
Int J Biol Sci ; 12(4): 427-45, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27019627

RESUMO

Breast cancer is the second leading cause of cancer-related mortality worldwide as most patients often suffer cancer relapse. The reason is often attributed to the presence of cancer stem cells (CSCs). Recent studies revealed that dysregulation of microRNA (miRNA) are closely linked to breast cancer recurrence and metastasis. However, no specific study has comprehensively characterised the CSC characteristic and miRNA transcriptome in spheroid-enriched breast cells. This study described the generation of spheroid MCF-7 cell in serum-free condition and the comprehensive characterisation for their CSC properties. Subsequently, miRNA expression differences between the spheroid-enriched CSC cells and their parental cells were evaluated using next generation sequencing (NGS). Our results showed that the MCF-7 spheroid cells were enriched with CSCs properties, indicated by the ability to self-renew, increased expression of CSCs markers, and increased resistance to chemotherapeutic drugs. Additionally, spheroid-enriched CSCs possessed greater cell proliferation, migration, invasion, and wound healing ability. A total of 134 significantly (p<0.05) differentially expressed miRNAs were identified between spheroids and parental cells using miRNA-NGS. MiRNA-NGS analysis revealed 25 up-regulated and 109 down-regulated miRNAs which includes some miRNAs previously reported in the regulation of breast CSCs. A number of miRNAs (miR-4492, miR-4532, miR-381, miR-4508, miR-4448, miR-1296, and miR-365a) which have not been previously reported in breast cancer were found to show potential association with breast cancer chemoresistance and self-renewal capability. The gene ontology (GO) analysis showed that the predicted genes were enriched in the regulation of metabolic processes, gene expression, DNA binding, and hormone receptor binding. The corresponding pathway analyses inferred from the GO results were closely related to the function of signalling pathway, self-renewability, chemoresistance, tumorigenesis, cytoskeletal proteins, and metastasis in breast cancer. Based on these results, we proposed that certain miRNAs identified in this study could be used as new potential biomarkers for breast cancer stem cell diagnosis and targeted therapy.


Assuntos
Neoplasias da Mama/metabolismo , MicroRNAs/genética , Células-Tronco Neoplásicas/metabolismo , Neoplasias da Mama/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Células MCF-7
12.
Drug Des Devel Ther ; 10: 1897-907, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27358555

RESUMO

Known as naturally occurring biologically active compounds, flavokawain A and B are the leading chalcones that possess anticancer properties. Another flavokawain derivative, (E)-1-(2'-Hydroxy-4',6'-dimethoxyphenyl)-3-(4-methylthio)phenyl)prop-2-ene-1-one (FLS) was characterized with (1)H-nuclear magnetic resonance, electron-impact mas spectrometry, infrared spectroscopy, and ultraviolet ((1)H NMR, EI-MS, IR, and UV) spectroscopic techniques. FLS cytotoxic efficacy against human cancer cells (MCF-7, MDA-MB-231, and MCF-10A) resulted in the reduction of IC50 values in a time- and dose-dependent mode with high specificity on MCF-7 (IC50 of 36 µM at 48 hours) against normal breast cell MCF-10A (no IC50 detected up to 180 µM at 72 hours). Light, scanning electron, and fluorescent microscopic analysis of MCF-7 cells treated with 36 µM of FLS displayed cell shrinkage, apoptotic body, and DNA fragmentation. Additionally, induction of G2/M cell arrest within 24 hours and apoptosis at subsequent time points was discovered via flow cytometry analysis. The roles of PLK-1, Wee-1, and phosphorylation of CDC-2 in G2/M arrest and proapoptotic factors (Bax, caspase 9, and p53) in promotion of apoptosis of FLS against MCF-7 cells were discovered using fluorometric, quantitative real-time polymerase chain reaction, and Western blot analysis. Interestingly, the presence of SCH3 (thiomethyl group) on ring B structure contributed to the selective cytotoxicity against MCF-7 cells compared to other chalcones, flavokawain A and B. Overall, our data suggest potential therapeutic value for flavokawain derivative FLS to be further developed as a new anticancer drug.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Compostos de Sulfidrila/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Neoplasias da Mama/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células MCF-7 , Estrutura Molecular , Relação Estrutura-Atividade , Compostos de Sulfidrila/síntese química , Compostos de Sulfidrila/química
13.
Artigo em Inglês | WPRIM | ID: wpr-630950

RESUMO

The human oral microbiome has been known to show strong association with various oral diseases including oral cancer. This study attempts to characterize the community variations between normal, oral potentially malignant disorders (OPMD) and cancer associated microbiota using 16S rDNA sequencing. Swab samples were collected from three groups (normal, OPMD and oral cancer) with nine subjects from each group. Bacteria genomic DNA was isolated in which full length 16S rDNA were amplified and used for cloned library sequencing. 16S rDNA sequences were processed and analysed with MOTHUR. A core oral microbiome was identified consisting of Firmicutes, Proteobacteria, Fusobacteria, Bacteroidetes and Actinobacteria at the phylum level while Streptococcus, Veillonella, Gemella, Granulicatella, Neisseria, Haemophilus, Selenomonas, Fusobacterium, Leptotrichia, Prevotella, Porphyromonas and Lachnoanaerobaculum were detected at the genus level. Firmicutes and Streptococcus were the predominant phylum and genus respectively. Potential oral microbiome memberships unique to normal, OPMD and oral cancer oral cavities were also identified. Analysis of Molecular Variance (AMOVA) showed a significant difference between the normal and the cancer associated oral microbiota but not between the OPMD and the other two groups. However, 2D NMDS showed an overlapping of the OPMD associated oral microbiome between the normal and cancer groups. These findings indicated that oral microbes could be potential biomarkers to distinguish between normal, OPMD and cancer subjects.

14.
J Inorg Biochem ; 102(11): 1997-2011, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18778856

RESUMO

The binding selectivity of the M(phen)(edda) (M=Cu, Co, Ni, Zn; phen=1,10-phenanthroline, edda=ethylenediaminediacetic acid) complexes towards ds(CG)(6), ds(AT)(6) and ds(CGCGAATTCGCG) B-form oligonucleotide duplexes were studied by CD spectroscopy and molecular modeling. The binding mode is intercalation and there is selectivity towards AT-sequence and stacking preference for A/A parallel or diagonal adjacent base steps in their intercalation. The nucleolytic properties of these complexes were investigated and the factors affecting the extent of cleavage were determined to be: concentration of complex, the nature of metal(II) ion, type of buffer, pH of buffer, incubation time, incubation temperature, and the presence of hydrogen peroxide or ascorbic acid as exogenous reagents. The fluorescence property of these complexes and its origin were also investigated. The crystal structure of the Zn(phen)(edda) complex is reported in which the zinc atom displays a distorted trans-N(4)O(2) octahedral geometry; the crystal packing features double layers of complex molecules held together by extensive hydrogen bonding that inter-digitate with adjacent double layers via pi...pi interactions between 1,10-phenanthroline residues. The structure is compared with that of the recently described copper(II) analogue and, with the latter, included in molecular modeling.


Assuntos
DNA/química , Ácido Edético/análogos & derivados , Níquel/química , Compostos Organometálicos/química , Fenantrolinas/química , Zinco/química , Sítios de Ligação , Dicroísmo Circular , Cobalto/química , Cobre/química , Cristalografia por Raios X , DNA/metabolismo , Clivagem do DNA , Ácido Edético/química , Ligação de Hidrogênio , Substâncias Intercalantes/química , Modelos Moleculares , Espectrometria de Fluorescência
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