RESUMO
Biomarker research in oral squamous cell carcinoma (OSCC) aims for screening/early diagnosis and in predicting its recurrence, metastasis and overall prognosis. This article reviews the current molecular perspectives and diagnosis of oral cancer with proteomics using matrix-assisted laser desorption ionization (MALDI) and surface-enhanced laser desorption ionization (SELDI) mass spectrometry (MS). This method shows higher sensitivity, accuracy, reproducibility and ability to handle complex tissues and biological fluid samples. However, the data interpretation tools of contemporary mass spectrometry still warrant further improvement. Based on the data available with laser-based mass spectrometry, biomarkers of OSCC are classified as (i) diagnosis and prognosis, (ii) secretory, (iii) recurrence and metastasis, and (iv) drug targets. Majority of these biomarkers are involved in cell homeostasis and are either physiologic responders or enzymes. Therefore, proteins directly related to tumorigenesis have more diagnostic value. Salivary secretory markers are another group that offers a favourable and easy strategy for non-invasive screening and early diagnosis in oral cancer. Key molecular inter-related pathways in oral carcinogenesis are also intensely researched with software analysis to facilitate targeted drug therapeutics. The review suggested the need for incorporating 'multiple MS or tandem approaches' and focusing on a 'group of biomarkers' instead of single protein entities, for making early diagnosis and treatment for oral cancer a reality.
Assuntos
Carcinoma de Células Escamosas/química , Neoplasias Bucais/química , Proteômica/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Biomarcadores Tumorais/análise , DNA de Neoplasias/análise , Detecção Precoce de Câncer , Humanos , Proteínas de Neoplasias/análiseRESUMO
Adult orthodontics is recently gaining popularity due to its importance in esthetics, oral and general health. However, none of the currently available alumina or zirconia based ceramic orthodontic brackets meet the esthetic demands of adult patients. Inherent hexagonal lattice structure and associated birefringence limits the visible light transmission in polycrystalline alumina and make them appear white and non transparent. Hence focus of the present study was to assess the feasibility of using magnesium aluminate (MgAl2O4) spinel; a member of the transparent ceramic family for esthetic orthodontic brackets. Transparent spinel specimens were developed from commercially available white spinel powder through colloidal shaping followed by pressureless sintering and hot isostatic pressing at optimum conditions of temperature and pressure. Samples were characterized for chemical composition, phases, density, hardness, flexural strength, fracture toughness and optical transmission. Biocompatibility was evaluated with in-vitro cell line experiments for cytotoxicity, apoptosis and genotoxicity. Results showed that transparent spinel samples had requisite physico-chemical, mechanical, optical and excellent biocompatibility for fabricating orthodontic brackets. Transparent spinel developed through this method demonstrated its possibility as a prospective biomaterial for developing esthetic orthodontic brackets.
Assuntos
Óxido de Alumínio/química , Óxido de Alumínio/farmacologia , Materiais Dentários/síntese química , Materiais Dentários/farmacologia , Estética Dentária , Óxido de Magnésio/química , Óxido de Magnésio/farmacologia , Braquetes Ortodônticos , Compostos de Alumínio/química , Compostos de Alumínio/farmacologia , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células HEK293 , Dureza , Humanos , Compostos de Magnésio/química , Compostos de Magnésio/farmacologia , Teste de Materiais , Refratometria , Propriedades de Superfície , Resistência à TraçãoRESUMO
Heavy metals are known for their associated nephrotoxicity and nickel is no exception. An integrated metabonomic approach, based on high-resolution (1) H NMR spectroscopy, was applied to determine the acute biochemical effects of NiCl(2) on the renal tissues of rats. Kidney homogenates from rats treated with NiCl(2) at two dose levels (4 and 20 mg kg(-1) b.w., i.p.) and those from controls were analysed using (1) H NMR spectroscopy and also assessed for antioxidant parameters at days 1, 3 and 5 post-dose. The major metabolite changes corresponding to nickel exposure were related to amino acids, osmolytes and energy metabolites. Differential responses were observed in (1) H NMR spectra with exposure to low and high doses of NiCl(2). For high doses, (1) H NMR spectral analysis revealed alterations in renal tissues, along with damage to the cortical and papillary region and depletion of renal osmolytes such as betaine, trimethyl amine oxide, myo-inositol and taurine, which persisted until day 5 post-dose. The metabolite profile of (1) H NMR spectra obtained from animals treated with lower dose of NiCl(2) initially increased as an immediate stress response and then showed signs of recovery with the passage of time. NMR spectral analysis was well corroborated with histopathological and oxidative stress results. Nickel-induced oxidative stress was observed in both groups of animals with increased levels of antioxidant parameters at initial time points, but continued to increase in the high-dose group. The present study shows a huge potential of metabonomics for mapping organ-based metabolic response during heavy metal toxicity.
Assuntos
Poluentes Ambientais/toxicidade , Rim/efeitos dos fármacos , Rim/metabolismo , Metaboloma/efeitos dos fármacos , Níquel/toxicidade , Animais , Antioxidantes/metabolismo , Relação Dose-Resposta a Droga , Rim/enzimologia , Rim/patologia , Espectroscopia de Ressonância Magnética , Masculino , Metabolômica , Ratos , Ratos Sprague-Dawley , Fatores de TempoRESUMO
The nuclear arsenal and the use of nuclear technologies have enhanced the likelihood of whole-body/partial-body radiation exposure. The central nervous system is highly susceptible to even low doses of radiation. With the aim of detecting and monitoring the pathologic changes of radiation-induced damage in brain parenchyma, we used serial diffusion tensor magnetic resonance imaging (DTI) with a 7T magnetic resonance unit and neurobehavioral assessments mice irradiated with 3-, 5-, and 8-Gy doses of radiation. Fractional anisotropy (FA) and mean diffusivity (MD) values at each time point (baseline, day 1, day 5, and day 10) were quantified from hippocampus, thalamus, hypothalamus, cudate-putamen, frontal cortex, sensorimotor cortex, corpus callosum, cingulum, and cerebral peduncle. Behavioral tests were performed at baseline, day 5, and day 10. A decrease in FA values with time was observed in all three groups. At day 10, dose-dependent decreases in FA and MD values were observed in all of the regions compared with baseline. Behavioral data obtained in this study correlate with FA values. Radiation-induced affective disorders were not radiation dose dependent, insofar as the anxiety-like symptoms at the lower dose (3 Gy) mimics to the symptoms with the higher dose (8 Gy) level but not with the moderate dose. However, there was a dose-dependent decline in cognitive function as well as FA values. Behavioral data support the DTI indices, so it is suggested that DTI may be a useful tool for noninvasive monitoring of radiation-induced brain injury.
Assuntos
Comportamento Animal/efeitos da radiação , Encéfalo/efeitos da radiação , Animais , Anisotropia , Mapeamento Encefálico , Imagem de Tensor de Difusão , Relação Dose-Resposta à Radiação , Comportamento Exploratório/efeitos da radiação , Raios gama , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos A , Reconhecimento Psicológico/efeitos da radiaçãoRESUMO
Thallium (Tl) is a toxic heavy metal and its exposure to the human body causes physiological and biochemical changes due to its interference with potassium-dependent biological reactions. A high-resolution (1)H NMR spectroscopy based metabonomic approach has been applied for investigating acute biochemical effects caused by thallium sulfate (Tl(2)SO(4)). Male strain A mice were divided in three groups and received three doses of Tl(2)SO(4) (5, 10 and 20 mg kg(-1) b.w., i.p.). Urine samples collected at 3, 24, 72 and 96 h post-dose time points were analyzed by (1)H NMR spectroscopy. NMR spectral data were processed and analyzed using principal components analysis to represent biochemical variations induced by Tl(2)SO(4). Results showed Tl-exposed mice urine to have distinct metabonomic phenotypes and revealed dose- and time-dependent clustering of treated groups. The metabolic signature of urine analysis from Tl(2)SO(4)-treated animals exhibited an increase in the levels of creatinine, taurine, hippurate and ß-hydroxybutyrate along with a decrease in energy metabolites trimethylamine and choline. These findings revealed Tl-induced disturbed gut flora, membrane metabolite, energy and protein metabolism, representing physiological dysfunction of vital organs. The present study indicates the great potential of NMR-based metabonomics in mapping metabolic response for toxicology, which could ultimately lead to identification of potential markers for Tl toxicity.
Assuntos
Espectroscopia de Ressonância Magnética/métodos , Intoxicação/urina , Tálio/toxicidade , Tálio/urina , Ácido 3-Hidroxibutírico/análise , Animais , Colina/metabolismo , Creatinina/análise , Intoxicação por Metais Pesados , Hipuratos/análise , Masculino , Metabolômica/métodos , Metais Pesados/toxicidade , Metais Pesados/urina , Metilaminas/metabolismo , Camundongos , Camundongos Endogâmicos A , Análise de Componente Principal , Taurina/análiseRESUMO
We report an unusual case of an anomalous intra-cavitary course of the right coronary artery (RCA) that was detected on multislice computed tomography (CT) angiography. Albeit rare, this anomaly is being picked up with increasing frequency owing to the widespread use of coronary CT angiography (CCTA). Although this entity does not produce symptoms per se, it can result in potentially catastrophic complications during interventional procedures or bypass surgeries if not recognized in time.
Assuntos
Angiografia Coronária , Anomalias dos Vasos Coronários/diagnóstico por imagem , Tomografia Computadorizada Multidetectores , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
The present study is the first report of the radiomodulatory effects of Psoralea corylifolia Linn. The extract (IBG-RA-26) prepared from P. corylifolia was chemically analysed by HPLC, LC-MS/MS and NMR. The total polyphenolic content of IBG-RA-26 was 0.287 mg/ml of quercetin equivalents. IBG-RA-26 exhibited a dose-dependent increase in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. It exhibited comparable (> 50%) site-specific and non-site-specific hydroxyl radical scavenging activity in higher concentration ranges (500-1000 microg/ml), while at lower concentrations (5-50 microg/ml) it exhibited significantly (p < 0.05) higher non-site-specific scavenging ability compared to site-specific activity. Nitric oxide scavenging activity of IBG-RA-26 (5-1000 microg/ml) increased in a concentration-dependent manner, while maximum superoxide ion scavenging ability (79%) was observed at 50 microg/ml. The electron donation potential of IBG-RA-26 was found to be higher than that of ascorbic acid at lower concentrations (up to 5 microg/ml). Analysis of the ability of IBG-RA-26 to protect membranes against gamma-radiation, utilizing an artificial membrane system (liposome), revealed a significant (p < 0.05) decrease in the formation of malondialdehyde (MDA) as a function of the concentration of IBG-RA-26. Radiation-induced lysis of human erythrocytes was monitored and efficacy of IBG-RA-26 was tested in the concentration range 25-1000 microg/ml, with significant protective efficacy observed in the range 25-50 microg/ml. IBG-RA-26 rendered significant (p < 0.05) protection against radiation (0.25 kGy)-induced DNA damage. EPR spectroscopy was used to investigate the DPPH radical scavenging capacity of IBG-RA-26. IBG-RA-26 exhibited a good DPPH radical scavenging capacity in a concentration-dependent manner. By direct EPR spectroscopy we have also demonstrated the possible formation of free radical species in a solution of IBG-RA-26. The wide spectrum of radioprotective and antioxidant properties exhibited by IBG-RA-26 indicate that P. corylifolia has potential as a radiomodulatory agent.
Assuntos
Espectroscopia de Ressonância de Spin Eletrônica/métodos , Sequestradores de Radicais Livres/farmacologia , Psoralea/química , Protetores contra Radiação/farmacologia , Cromatografia Líquida de Alta Pressão , Sequestradores de Radicais Livres/isolamento & purificação , Hemólise/efeitos dos fármacos , Humanos , Técnicas In Vitro , Espectroscopia de Ressonância Magnética , Protetores contra Radiação/isolamento & purificação , Espectrometria de Massas em TandemRESUMO
During normal haematopoiesis, cell development and differentiation programs are accomplished by switching 'on' and 'off' specific set of genes. Specificity of gene expression is primarily achieved by combinatorial control, i.e. through physical and functional interactions among several transcription factors that form sequence-specific multiprotein complexes on regulatory regions (gene promoters and enhancers). Such combinatorial gene switches permit flexibility of regulation and allow numerous developmental decisions to be taken with a limited number of regulators. The haematopoietic-specific Ets family transcription factor PU.1 regulates many lymphoid- and myeloid-specific gene promoters and enhancers by interacting with multiple proteins during haematopoietic development. Such protein-protein interactions regulate DNA binding, subcellular localization, target gene selection and transcriptional activity of PU.1 itself in response to diverse signals including cytokines, growth factors, antigen and cellular stresses. Specific domains of PU.1 interact with many protein motifs such as bHLH, bZipper, zinc fingers and paired domain for regulating its activity. This review focuses on important protein-protein interactions of PU.1 that play a crucial role in regulation of normal as well as malignant haematopoiesis. Precise delineation of PU.1 protein-partner interacting interface may provide an improved insight of the molecular mechanisms underlying haematopoietic stem cell fate regulation. Its interactions with some proteins could be targeted to modulate the aberrant signalling pathways for reversing the malignant phenotype and to control the generation of specific haematopoietic progeny for treatment of haematopoietic disorders.
Assuntos
Linhagem da Célula , Neoplasias Hematológicas/metabolismo , Neoplasias Hematológicas/patologia , Hematopoese , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Transativadores/metabolismo , Animais , Humanos , Ligação Proteica , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/genética , Transativadores/química , Transativadores/genéticaRESUMO
Region of interest based morphometric diffusion tensor imaging analysis, has been used extensively for the assessment of age-related changes in human brain, is limited to two dimensions and does not reflect the whole fiber bundle; however, diffusion tensor tractography (DTT) offers an overall view of individual fiber bundle in three-dimensional spaces. Quantitative DTT was performed on 51 healthy subjects of pediatric age range and young adults to compare age-related fractional anisotropy (FA) changes in corpus callosum, sensory and motor pathways, limbic tracts [cingulum (CNG) and fornix (Fx)], and superior and inferior longitudinal fascicules. In corpus callosum, inferior longitudinal fascicules, limbic tracts (CNG and Fx), sensory pathways, and motor pathways, an initial sharp increase in FA was observed up to the age of 2 y followed by a gradual increase up to 21 y. In superior longitudinal fascicules, sharp increase in FA was observed up to 3 y followed by a gradual increase. The FA value of the left CNG (p = 0.01, sign test) was observed to be significantly greater than that of the right CNG. We conclude that white matter fiber tracts mature with age and can be assessed by using DTT that may greatly improve our understanding of the human brain development.
Assuntos
Encéfalo/crescimento & desenvolvimento , Imagem de Tensor de Difusão/métodos , Lateralidade Funcional/fisiologia , Vias Neurais/crescimento & desenvolvimento , Adolescente , Fatores Etários , Anisotropia , Encéfalo/anatomia & histologia , Criança , Pré-Escolar , Humanos , Lactente , Vias Neurais/anatomia & histologia , Adulto JovemRESUMO
It has been previously hypothesized that the high fractional anisotropy (FA) values in leptomeningeal cortical subcortical white matter (LCSWM) regions of neonatal brain with bacterial meningitis is due to the presence of adhesion molecules in the subarachnoid space, which are responsible for adherence of inflammatory cells over the subarachnoid membrane. The aim of this study was to look for any relationship between FA values in LCSWM regions and various neuroinflammatory molecules (NMs) in cerebrospinal fluid (CSF) measured in neonates with bacterial meningitis. Diffusion tensor imaging was performed on 18 term neonates (median age, 10.5 days) having bacterial meningitis and 10 age-/sex-matched healthy controls. CSF enzyme-linked immunosorbent assay was performed to quantify NMs [soluble intracellular adhesion molecules (sICAM), tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta)]. Significantly increased FA values were observed in LCSWM regions of the patients compared to controls. A significant positive correlation was observed between FA values in LCSWM regions and NMs [sICAM (r=0.67, P=.006), TNF-alpha (r=0.69, P=.005) and IL-1beta (r=0.82, P=.000)] in CSF of these patients. No difference in FA values (P=.99) in LCSWM regions was observed between patients with sterile (0.12+/-0.02) and culture-positive CSF study (0.12+/-0.02). FA may be used as noninvasive surrogate marker of NMs in neonatal meningitis in assessing therapeutic response in future.
Assuntos
Moléculas de Adesão Celular/líquido cefalorraquidiano , Córtex Cerebral/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Meningites Bacterianas/líquido cefalorraquidiano , Anisotropia , Estudos de Casos e Controles , Meios de Contraste , Ensaio de Imunoadsorção Enzimática , Feminino , Gadolínio DTPA , Humanos , Recém-Nascido , Molécula 1 de Adesão Intercelular/líquido cefalorraquidiano , Interleucina-1beta/líquido cefalorraquidiano , Masculino , Meningites Bacterianas/microbiologia , Punção Espinal , Fator de Necrose Tumoral alfa/líquido cefalorraquidianoRESUMO
The metabolic changes in the brain of patients affected with Type 2 diabetes mellitus (DM) alone, both Type 2 DM and hypothyroidism and hypothyroidism only were investigated using proton magnetic resonance spectroscopy ((1)H MRS). Single-voxel spectroscopy was carried out in right and left frontal lobe white matter, left parietal white matter and left occipital gray matter. Choline (Cho)/creatine (Cr) value was found to be increased in the left occipital gray matter of the subjects affected with Type 2 DM and both Type 2 DM and hypothyroidism as compared to controls. No significant change in the Cho/Cr value in the occipital gray matter was observed in hypothyroid subjects as compared to controls. However, they showed an increased level of Cho/Cr in the frontal white matter. High Cho is associated with altered membrane phospholipid metabolism. The high Cho in frontal white matter in hypothyroids and occipital gray matter in diabetic patients suggests that, though both the diseases are endocrine disorders, they differ from each other in terms of regional brain metabolite changes.
Assuntos
Encéfalo/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Hipotireoidismo/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Adulto , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Colina/metabolismo , Creatina/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prótons , Processamento de Sinais Assistido por ComputadorRESUMO
The majority of human mild traumatic brain injuries (mTBI; 70%) lack radiological evidence of injury, yet may present long term cognitive, and behavioral dysfunctions. With the hypothesis of evident damaged neural tissue and immunological consequences during acute phase of mTBI, we used closed skull weight-drop TBI model to address human mTBI condition. Serum cytokines (TNF-α, IL-10) and glial fibrillary acidic protein (GFAP) expression were examined at day 0 (control, pre-injury), 4h, day 1, day 3 and day 5 post injury (PI). Diffusion tensor imaging (DTI) was performed at similar timepoints to identify neuroinflammation translation into imaging abnormalities and monitor injury progression. DTI indices including mean diffusivity (MD), radial diffusivity (RD), fractional anisotropy and axial diffusivity values were quantified from cortex (CTX), hippocampus and corpus callosum regions. One way ANOVA showed significant increase in TNF-α at 4h and IL-10 at day 1 PI as compared to control. GFAP(+) cells were significantly increased at day 3 and day 5 as compared to control in CTX. Repeated measures ANOVA revealed significant decreases in MD, RD values in CTX at day 3 and day 5 as compared to day 0. A significant, inverse correlation was observed between cortical MD (r=-0.74, p=0.01), AD (r=-0.60, p=0.03) and RD (r=-0.72, p=0.01) values with mean GFAP(+) cells in the cortical region. These findings suggest that mTBI leads to elevated cytokine expression and subsequent hypertrophy of astrocytic processes. The increased numbers of reactive glial cells contribute diffusion restrictions in the CNS leading to reduced MD and RD values. These findings are in line with the deficits and pathologies associated with clinical mTBI, and support the use of mTBI model to address pathology and therapeutic options.
Assuntos
Lesões Encefálicas/sangue , Lesões Encefálicas/patologia , Citocinas/sangue , Imagem de Tensor de Difusão/tendências , Proteína Glial Fibrilar Ácida/biossíntese , Animais , Autoanticorpos/sangue , Biomarcadores/sangue , Encéfalo/metabolismo , Encéfalo/patologia , Regulação da Expressão Gênica , Masculino , Ratos , Ratos Sprague-Dawley , Fatores de TempoRESUMO
Synthesis of a contrast agent for biomedical imaging is of great interest where magnetic nanoparticles are concerned, because of the strong influence of particle size on transverse relaxivity. In the present study, biocompatible magnetic iron oxide nanoparticles were synthesized by co-precipitation of Fe2+ and Fe3+ salts, followed by surface adsorption with reduced dextran. The synthesized nanoparticles were spherical in shape, and 12 ± 2 nm in size as measured using transmission electron microscopy; this was corroborated with results from X-ray diffraction and dynamic light scattering studies. The nanoparticles exhibited superparamagnetic behavior, superior T2 relaxation rate and high relaxivities (r1 = 18.4 ± 0.3, r2 = 90.5 ± 0.8 s-1 mM-1 , at 7 T). MR image analysis of animals before and after magnetic nanoparticle administration revealed that the signal intensity of tumor imaging, specific organ imaging and whole body imaging can be clearly distinguished, due to the strong relaxation properties of these nanoparticles. Very low concentrations (3.0 mg Fe/kg body weight) of iron oxides are sufficient for early detection of tumors, and also have a clear distinction in pre- and post-enhancement of contrast in organs and body imaging. Many investigators have demonstrated high relaxivities of magnetic nanoparticles at superparamagnetic iron oxide level above 50 nm, but this investigation presents a satisfactory, ultrasmall, superparamagnetic and high transverse relaxivity negative contrast agent for diagnosis in pre-clinical studies. Copyright © 2016 John Wiley & Sons, Ltd.
Assuntos
Meios de Contraste/química , Dextranos , Imageamento por Ressonância Magnética/métodos , Nanopartículas de Magnetita , Nanopartículas/química , Animais , Carcinoma de Ehrlich/diagnóstico por imagem , Meios de Contraste/síntese química , Meios de Contraste/farmacocinética , Dextranos/administração & dosagem , Dextranos/síntese química , Dextranos/farmacocinética , Humanos , Nanopartículas de Magnetita/administração & dosagem , Camundongos , Nanopartículas/administração & dosagem , Neoplasias/diagnóstico por imagem , Especificidade de ÓrgãosRESUMO
Homing and engraftment, a determining factor in hematopoietic stem cell transplantation success is defined as a process through which hematopoietic stem/progenitor cells (HSPCs) lodge recipient bone marrow. SDF-1/CXCR4 axis acts as a principle regulator in homing and engraftment, however, CXCR4 signaling is dependent upon expression of CXCR4 and its ligand SDF-1, which is highly dynamic. Hence, present investigation was aimed to explore the potential of CXCR4 constitutive active mutants (CXCR4-CAMs) in overcoming the limitation of CXCR4 signaling and up-modulate its efficiency in homing and engraftment. Regulated transgene expression study of these mutants revealed their significantly enhanced cell adhesion efficiency to endothelium and extracellular matrix protein. This altogether indicates promising prospects of CXCR4-CAMs in research aimed to improve HSPCs engraftment efficiency.
Assuntos
Quimiocina CXCL12/genética , Células-Tronco Hematopoéticas/citologia , Receptores CXCR4/genética , Transdução de Sinais , Adesão Celular , Movimento Celular , Transplante de Células-Tronco Hematopoéticas , Humanos , Células K562 , TransgenesRESUMO
Radiation exposure is a serious threat to biomolecules, particularly DNA, proteins and lipids. Various exogenous substances have been reported to protect these biomolecules. In this study we explored the effect of pre-treatment with G-002M, a mixture of three active derivatives isolated from the rhizomes of Podophyllum hexandrum, on DNA damage response in irradiated human blood leukocytes. Blood was collected from healthy male volunteers, preincubated with G-002M and then irradiated with various doses of radiation. Samples were analyzed using flow cytometry to quantify DNA double strand break (DSB) biomarkers including γ-H2AX, P53BP1 and levels of ligase IV. Blood samples were irradiated in vitro and processed to determine time and dose-dependent kinetics. Semiquantitative RT-PCR was performed at various time points to measure gene expression of DNA-PKcs, Ku80, ATM, and 53BP1; each of these genes is involved in DNA repair signaling. Pre-treatment of blood with G-002M resulted in reduction of γ-H2AX and P53BP1 biomarkers levels and elevated ligase IV levels relative to non-G-002M-treated irradiated cells. These results confirm suppression in radiation-induced DNA DSBs. Samples pre-treated with G-002M and then irradiated also showed significant up-regulation of DNA-PKcs and Ku80 and downregulation of ATM and 53BP1 gene expressions, suggesting that G-002M plays a protective role against DNA damage. The protective effect of G-002M may be due to its ability to scavange radiation-induced free radicals or assist in DNA repair. Further studies are needed to decipher the role of G-002M on signaling molecules involved in radiation-induced DNA damage repair pathways.
Assuntos
Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Flavonoides/farmacologia , Raios gama/efeitos adversos , Leucócitos/efeitos dos fármacos , Podophyllum/química , Protetores contra Radiação/farmacologia , Antígenos Nucleares/genética , Antígenos Nucleares/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Berberidaceae , Células Cultivadas , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Reparo do DNA/genética , Reparo do DNA/efeitos da radiação , Proteína Quinase Ativada por DNA/genética , Proteína Quinase Ativada por DNA/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Flavonoides/química , Histonas/genética , Histonas/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Autoantígeno Ku , Leucócitos/metabolismo , Leucócitos/efeitos da radiação , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Linfócitos/efeitos da radiação , Masculino , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Monócitos/efeitos da radiação , Fosforilação/efeitos dos fármacos , Fosforilação/efeitos da radiação , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína 1 de Ligação à Proteína Supressora de Tumor p53RESUMO
OBJECTIVES: The purpose of this study was to evaluate the performance of l-[methyl-()11C]methionine (11C-MET) PET/CT and MRI (with the inclusion of advanced imaging techniques, namely, MR spectroscopy and MR perfusion) in the assessment of tumor recurrence in high-grade gliomas. PATIENTS AND METHODS: Twenty-nine patients with high-grade gliomas who underwent surgical resection, external beam radiation therapy, and standard regimens of chemotherapy were subjected to MRI (conventional, MR perfusion, and MR spectroscopy) and 11C-MET PET/CT scans. A definitive diagnosis was made based on histopathology and/or long-term clinical and radiological follow-up. Several indices were obtained for lesion characterization, namely, SUVmean, SUVmax, and mean lesion-to-normal tissue on PET/CT, as well as relative cerebral blood volume and choline-to-creatine ratio on MRI. RESULTS: Histological examination revealed viable tumor cells in 19 cases, whereas the remaining 10 were deemed to be negative based on histology (3 cases) or long-term follow-up (7 cases). All the quantitative indices mentioned previously tended to be higher in patients with tumor recurrence/residual. The sensitivity, specificity, and accuracy of 11C-MET PET/CT in identifying tumor recurrence/residual were 94.7%, 80%, and 89.6%, respectively, whereas that of MRI were 84.2%, 90%, and 86.2%, respectively. CONCLUSIONS: Both 11C-MET PET/CT and MRI (with the inclusion of advanced MRI techniques) demonstrated a high diagnostic performance in the identification of tumor residual/recurrence in high-grade gliomas posttherapy. Although 11C-MET PET/CT seemed to be more sensitive, whereas advanced MRI seemed more specific, there was no statistically significant difference in the diagnostic performance of either modality in the present study. Further studies with a larger group of patients are warranted.
Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Glioma/diagnóstico por imagem , Imageamento por Ressonância Magnética , Imagem Multimodal , Recidiva Local de Neoplasia/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Radioisótopos de Carbono , Feminino , Glioma/patologia , Glioma/terapia , Humanos , Masculino , Metionina/análogos & derivados , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Compostos RadiofarmacêuticosRESUMO
Human mesenchymal stem cells (hMSCs) present in the bone marrow are the precursors of osteoblasts, chondrocytes and adipocytes, and hold tremendous potential for osteoregenerative therapy. However, achieving directed differentiation into osteoblasts has been a major concern. The use of lithium for enhancing osteogenic differentiation has been documented in animal models but its effect in humans is not clear. We, therefore, performed high throughput transcriptome analysis of lithium-treated hMSCs to identify altered gene expression and its relevance to osteogenic differentiation. Our results show suppression of proliferation and enhancement of alkaline phosphatase (ALP) activity upon lithium treatment of hMSCs under non-osteogenic conditions. Microarray profiling of lithium-stimulated hMSC revealed decreased expression of adipogenic genes (CEBPA, CMKLR1, HSD11B1) and genes involved in lipid biosynthesis. Interestingly, osteoclastogenic factors and immune responsive genes (IL7, IL8, CXCL1, CXCL12, CCL20) were also downregulated. Negative transcriptional regulators of the osteogenic program (TWIST1 and PBX1) were suppressed while genes involved in mineralization like CLEC3B and ATF4 were induced. Gene ontology analysis revealed enrichment of upregulated genes related to mesenchymal cell differentiation and signal transduction. Lithium priming led to enhanced collagen 1 synthesis and osteogenic induction of lithium pretreated MSCs resulted in enhanced expression of Runx2, ALP and bone sialoprotein. However, siRNA-mediated knockdown of RRAD, CLEC3B and ATF4 attenuated lithium-induced osteogenic priming, identifying a role for RRAD, a member of small GTP binding protein family, in osteoblast differentiation. In conclusion, our data highlight the transcriptome reprogramming potential of lithium resulting in higher propensity of lithium "primed" MSCs for osteoblastic differentiation.
Assuntos
Diferenciação Celular , Perfilação da Expressão Gênica , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/citologia , Transcriptoma , Fosfatase Alcalina/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Núcleo Celular/metabolismo , Proliferação de Células , Ativação Enzimática/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Glicogênio Sintase Quinase 3 beta , Humanos , Lítio/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Anotação de Sequência Molecular , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Transporte Proteico/efeitos dos fármacos , Reprodutibilidade dos Testes , Transcrição Gênica/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/metabolismoRESUMO
Trait anxiety, a personality dimension that measures an individual's higher disposition to anxiety, has been found to be associated with many functional consequences viz. increased distractibility, attentional bias in favor of threat-related information etc. Similarly, volumetric studies have reported morphological changes viz. a decrease in the volume of left uncinate fasciculus (fiber connecting anterior temporal areas including the amygdala with prefrontal-/orbitofrontal cortices) and an increase in the volume of the left amygdala and right hippocampus, to be associated with trait anxiety. The functional and morphological changes associated with trait anxiety might also be associated with the changes in the integrity of WM tracts in relation with the trait anxiety levels of the subjects. Therefore, in the present diffusion tensor tractography (DTT) study, we investigated the possible relationship between the diffusion tensor imaging (DTI) derived indices of a wide array of fiber tracts and the trait anxiety scores in our subject group. A positive correlation between trait anxiety scores and the mean fractional anisotropy (FA) value was obtained in fornix and left uncinate fasciculus. The study provides first account of a positive relation between sub-clinical anxiety levels of subjects and the FA of fornix thereby providing interesting insights into the biological foundation of sub-clinical anxiety.
Assuntos
Ansiedade/fisiopatologia , Fórnice/fisiopatologia , Fibras Nervosas Mielinizadas/fisiologia , Adulto , Mapeamento Encefálico , Imagem de Tensor de Difusão , Feminino , Humanos , Individualidade , Masculino , AutorrelatoRESUMO
A 58-year-old woman with breast carcinoma, after mastectomy, radiotherapy, and chemotherapy, underwent a whole-body F-18 FDG PET/CT for restaging, which revealed multiple skeletal metastasis. Hypometabolism was noted in the right frontal lobe. The patient subsequently underwent a C-11 methionine brain scan, which demonstrated multiple dural-based metastatic foci confirmed on contrast-enhanced MR. FDG PET has limitations in brain tumor detection. Amino acid tracers are particularly attractive for imaging of brain tumors because of relatively high tumor to brain activity ratios.
Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Dura-Máter/diagnóstico por imagem , Fluordesoxiglucose F18 , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/secundário , Metionina , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Neoplasias Encefálicas/secundário , Dura-Máter/patologia , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
Homing and engraftment of hematopoietic stem/progenitor cells (HSPCs) in bone marrow is the major determining factor in success of hematopoietic stem cell transplantation. This is a complex, multistep process orchestrated by the coordinated interplay between adhesion molecules, cytokines, growth factors, and regulatory cofactors, many of which remain to be defined. Recent studies have highlighted the pivotal role of unique stromal-derived factor-1 (SDF-1)/CXCR4 signaling in the regulation of HSPC homing and subsequent engraftment. In addition, studies suggest that SDF-1/CXCR4 signaling acts as an essential survival-promoting factor of transplanted HSPCs as well as maintenance of quiescent HSCs in bone marrow niche. These pleiotropic effects exerted by SDF-1/CXCR4 axis make this unique signaling initiator very promising, not only for optimal hematopoietic reconstitution but also for the development of innovative approaches to achieve restoration, regeneration, or repair of other damaged tissues potentially amendable to reversal by stem cell transplantation. This goal can only be achieved when the role of SDF-1/CXCR4 axis in hematopoietic transplantation is clearly defined. Hence, this review presents current knowledge of the mechanisms through which SDF-1/CXCR4 signaling promotes restoration of hematopoiesis by regulating the homing and engraftment of HSPCs.