RESUMEN
Normal-to-cancer (NTC) transition is known to be closely associated to cell´s biomechanical properties which are dependent on the dynamics of the intracellular medium. This study probes different human cancer cells (breast, prostate and lung), concomitantly to their healthy counterparts, aiming at characterising the dynamical profile of water in distinct cellular locations, for each type of cell, and how it changes between normal and cancer states. An increased plasticity of the cytomatrix is observed upon normal-to-malignant transformation, the lung carcinoma cells displaying the highest flexibility followed by prostate and breast cancers. Also, lung cells show a distinct behaviour relative to breast and prostate, with a higher influence from hydration water motions and localised fast rotations upon NTC transformation. Quasielastic neutron scattering techniques allowed to accurately distinguish the different dynamical processes taking place within these highly heterogeneous cellular systems. The results thus obtained suggest that intracellular water dynamics may be regarded as a specific reporter of the cellular conditions-either healthy or malignant.
Asunto(s)
Neoplasias , Agua , Humanos , Difracción de Neutrones , NeutronesRESUMEN
OBJECTIVES: To quantify the physical activity levels in dogs with cranial cruciate ligament rupture before and after lateral fabellar suture stabilisation surgery. MATERIALS AND METHODS: Seventeen dogs (mean weight, 12.3±5.1 kg) with unilateral cranial cruciate ligament rupture were fitted with an accelerometer for seven consecutive days at four different time points: before surgery (T0), one (T1), three (T3) and six (T6) months after surgery. The total activity and times spent in sedentary activity, light to moderate activity and vigorous activity were recorded by the accelerometer, and preoperative and postoperative data were compared. At all time points, dogs underwent clinical evaluations (lameness score, stifle pain score and thigh circumference) and their owners were asked to respond to questionnaires to subjectively score the physical activity and quality of life of the dogs. RESULTS: At the four time points, the dogs spent between 21.2 and 21.4 hours on sedentary behaviour, 2.3 and 2.5 hours performing light to moderate activity, and 13 to 15 minutes performing vigorous activity. There was no increase in physical activity variables or decrease in sedentary behaviour over time. Lameness scores, pain score and dogs' quality of life improved significantly during the postoperative period. At T6, 17 (100%) of 17 dogs presented no lameness, 16 (94%) of 17 dogs presented no stifle pain, 16 (94%) of 17 owners rated the quality of life as very good and excellent, and 16 (100%) of 16 owners reported a total return to normal activity levels. CLINICAL SIGNIFICANCE: The clinical recovery after extracapsular stabilisation of the stifle joint was not associated with a spontaneous increase in physical activity or a decrease in sedentary behaviour.
Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Enfermedades de los Perros , Condicionamiento Físico Animal , Perros , Animales , Ligamento Cruzado Anterior/cirugía , Cojera Animal/cirugía , Calidad de Vida , Enfermedades de los Perros/cirugía , Lesiones del Ligamento Cruzado Anterior/cirugía , Lesiones del Ligamento Cruzado Anterior/veterinaria , Rodilla de Cuadrúpedos/cirugía , Dolor/veterinaria , Acelerometría/veterinaria , Rotura/cirugía , Rotura/veterinariaRESUMEN
Normal-to-malignant transformation is a poorly understood process associated with cellular biomechanical properties. These are strongly dependent on the dynamical behaviour of water, known to play a fundamental role in normal cellular activity and in the maintenance of the three-dimensional architecture of the tissue and the functional state of biopolymers. In this study, quasi-elastic neutron scattering was used to probe the dynamical behaviour of water in human cancer specimens and their respective surrounding normal tissue from breast and tongue, as an innovative approach for identifying particular features of malignancy. This methodology has been successfully used by the authors in human cells and was the first study of human tissues by neutron scattering techniques. A larger flexibility was observed for breast versus tongue tissues. Additionally, different dynamics were found for malignant and non-malignant specimens, depending on the tissue: higher plasticity for breast invasive cancer versus the normal, and an opposite effect for tongue. The data were interpreted in the light of two different water populations within the samples: one displaying bulk-like dynamics (extracellular and intracellular/cytoplasmic) and another with constrained flexibility (extracellular/interstitial and intracellular/hydration layers).
Asunto(s)
Neoplasias , Agua , Humanos , Difracción de Neutrones/métodos , NeutronesRESUMEN
Mutations linked to neurodevelopmental disorders, such as intellectual disability (ID), are frequently found in genes that encode for proteins of the excitatory synapse. Transmembrane AMPA receptor regulatory proteins (TARPs) are AMPA receptor auxiliary proteins that regulate crucial aspects of receptor function. Here, we investigate a mutant form of the TARP family member stargazin, described in an ID patient. Molecular dynamics analyses predicted that the ID-associated stargazin variant, V143L, weakens the overall interface of the AMPAR:stargazin complex and impairs the stability of the complex. Knock-in mice harboring the V143L stargazin mutation manifest cognitive and social deficits and hippocampal synaptic transmission defects, resembling phenotypes displayed by ID patients. In the hippocampus of stargazin V143L mice, CA1 neurons show impaired spine maturation, abnormal synaptic transmission and long-term potentiation specifically in basal dendrites, and synaptic ultrastructural alterations. These data suggest a causal role for mutated stargazin in the pathogenesis of ID and unveil a new role for stargazin in the development and function of hippocampal synapses.
Asunto(s)
Canales de Calcio , Discapacidad Intelectual , Receptores AMPA , Animales , Canales de Calcio/genética , Canales de Calcio/metabolismo , Hipocampo/metabolismo , Humanos , Discapacidad Intelectual/genética , Discapacidad Intelectual/metabolismo , Ratones , Mutación/genética , Receptores AMPA/genética , Receptores AMPA/metabolismo , Sinapsis/metabolismo , Transmisión Sináptica/genéticaRESUMEN
Protein crystallization still remains mostly an empirical science, as the production of crystals with the required quality for X-ray analysis is dependent on the intensive screening of the best protein crystallization and crystal's derivatization conditions. Herein, this demanding step was addressed by the development of a high-throughput and low-budget microfluidic platform consisting of an ion exchange membrane (117 Nafion® membrane) sandwiched between a channel layer (stripping phase compartment) and a wells layer (feed phase compartment) forming 75 independent micro-contactors. This microfluidic device allows for a simultaneous and independent screening of multiple protein crystallization and crystal derivatization conditions, using Hen Egg White Lysozyme (HEWL) as the model protein and Hg2+ as the derivatizing agent. This microdevice offers well-regulated crystallization and subsequent crystal derivatization processes based on the controlled transport of water and ions provided by the 117 Nafion® membrane. Diffusion coefficients of water and the derivatizing agent (Hg2+) were evaluated, showing the positive influence of the protein drop volume on the number of crystals and crystal size. This microfluidic system allowed for crystals with good structural stability and high X-ray diffraction quality and, thus, it is regarded as an efficient tool that may contribute to the enhancement of the proteins' crystals structural resolution.
RESUMEN
Um filhote de porquinho-da-índia (Cavia porcellus) foi recebido para atendimento após histórico de ataque por cão. Na avaliação física, observou-se edema, dor e crepitação em membro pélvico direito, sugestivo de fratura. Na avaliação radiográfica, confirmou-se fratura Salter-Harris tipo I em epífise distal da tíbia. A resolução cirúrgica escolhida foi a associação de pino transarticular e coaptação externa com tala de Altman. O paciente teve acompanhamento radiográfico semanal e obteve alta médica no 35o dia de pós-cirúrgico, quando se observou consolidação com completo remodelamento ósseo.(AU)
A guinea pig (Cavia porcellus) cub presented edema, pain, and crepitus in the right pelvic limb after being attacked by a dog. Radiographic examination revealed Salter-Harris type 1 fracture on the distal region of the tibia. The surgery technique to correct the fracture involved an association of transarticular pinning and external coaptation with Altman splint. After surgery, radiographs of the patient were performed weekly and on the 35th post-surgery day, the bone was completely remodeled and healed, and the animal was dismissed.(AU)
Asunto(s)
Animales , Roedores/lesiones , Clavos Ortopédicos/veterinaria , Fijación Intramedular de Fracturas/veterinaria , Fracturas de la Tibia/veterinaria , Epífisis/lesionesRESUMEN
The transition from normal to malignant state in human cells is still a poorly understood process. Changes in the dynamical activity of intracellular water between healthy and cancerous human cells were probed as an innovative approach for unveiling particular features of malignancy and identifying specific reporters of cancer. Androgen-unresponsive prostate and triple-negative breast carcinomas were studied as well as osteosarcoma, using the technique of quasi-elastic neutron scattering. The cancerous cells showed a considerably higher plasticity relative to their healthy counterparts, this being more significant for the mammary adenocarcinoma. Also, the data evidence that the prostate cancer cells display the highest plasticity when compared to triple-negative mammary cancer and osteosarcoma, the latter being remarkably less flexible. Furthermore, the results suggest differences between the flexibility of different types of intracellular water molecules in normal and cancerous cells, as well as the number of molecules involved in the different modes of motion. The dynamics of hydration water molecules remain virtually unaffected when going from healthy to cancer cells, while cytoplasmic water (particularly the rotational motions) undergoes significant changes upon normal-to-cancer transition. The results obtained along this study can potentially help to understand the variations in cellular dynamics underlying carcinogenesis and tumor metastasis, with an emphasis on intracellular water.
RESUMEN
The present study suggests that insulin resistance has no association with bone quantity, but quality. INTRODUCTION: The literature has contradictory results concerning the influence of insulin resistance on bone. The present study sought to evaluate the association of insulin resistance and adipose tissue with either bone mineral density or the trabecular bone score. METHODS: The study included 56 individuals (36 women and 20 men): age = 46.6 ± 14.2 years, weight = 67.8 ± 10.9 kg, height = 1.65 ± 0.10 m and BMI = 24.8 ± 3.9 kg/m2. The investigational protocol included biochemical determinations and bone assessment by dual X-ray absorptiometry for evaluation of bone mineral density and trabecular bone score. Magnetic resonance was employed to estimate visceral, subcutaneous and bone marrow adipose tissues, as well as intrahepatic lipids. RESULTS: The bone mineral density of the lumbar spine, femoral neck and total hip were not associated with insulin resistance-related parameters [visceral adipose tissue, intrahepatic lipids and homeostatic model assessment of insulin resistance (HOMA-IR)]. In contrast, there was a negative relationship between the trabecular bone score and all these components. The association between the trabecular bone score and HOMA-IR was reinforced after adjustment for age and BMI. Marrow adipose tissue was negatively associated with both bone mineral density and trabecular bone score. CONCLUSIONS: The present study shows that the trabecular bone score is negatively associated with marrow adipose tissue, insulin resistance, visceral adipose tissue and intrahepatic lipid measurements. Additionally, there was a negative relationship between saturated lipids in marrow adipose tissue and the trabecular bone score. These results encourage further studies to investigate the role of the trabecular bone score exam in the clinical evaluation of osteoporosis in conditions of insulin resistance.
Asunto(s)
Tejido Adiposo/diagnóstico por imagen , Densidad Ósea , Hueso Esponjoso/diagnóstico por imagen , Resistencia a la Insulina , Absorciometría de Fotón , Adulto , Médula Ósea , Femenino , Humanos , Grasa Intraabdominal , Lípidos/análisis , Hígado/química , Imagen por Resonancia Magnética , Masculino , Persona de Mediana EdadRESUMEN
O presente artigo é um relato sobre uma fêmea de D. novemcinctus que foi capturada de forma imprevista, durante um projeto de avaliação sanitária de animais silvestres sinantrópicos do município de Toledo/PR (autorização Sisbio/Ibama n. 55109-1). Durante a avaliação física, amostras de fezes foram coletadas após defecação espontânea e encaminhadas para análise. O material foi submetido aos métodos de flutuação simples em solução hipersaturada de cloreto de sódio e centrífugo-flutuação em sacarose. Na leitura das lâminas obtidas pelo método de centrífugo-flutuação em sacarose, foram observadas estruturas com comprimento de aproximadamente 10µm, forma bicônica e um tampão em cada extremidade, compatíveis com esporocistos de Monocystis sp. Protozoários do filo Apicomplexa, os Monocystis sp., são geralmente parasitas de anelídeos, como as minhocas. Esse organismo é comumente correlato a pseudoparasitismo em vários animais, porém não foram encontrados relatos de pseudoparasitismo desse agente em tatus-galinhas, logo essa é a primeira descrição de Monocystis sp. em espécime de D. novemcinctus.(AU)
The present article is an account of a female of D. novemcinctus which was captured during a sanitary evaluation project of synanthropic wild animals of the municipality of Toledo/PR (license SISBIO/ICMBIO n°. 55109-1). During a physical evaluation, samples of feces were collected, after spontaneous defecation, and sent for analysis. The material was subjected to simple flotation methods in hypersaturated sodium chloride solution and centrifugal-flotation solutions in sucrose. In a test reading by the centrifugal-flotation method in sucrose, structures with approximately 10µm, biconical shape and one plate at each end were observed, compatible with sporocysts of Monocystis sp. Protozoa of the phylum Apicomplexa, like Monocystis sp., it is common parasitic annelids, such as worms. This organism is a correlate of pseudoparasitism in several animals but was not found to describe this product as an agent in nine banded armadillos, so this is a first description of Monocystis sp. in specimen of D. novemcinctus.(AU)
Asunto(s)
Animales , Femenino , Armadillos/parasitología , Apicomplexa/parasitología , Animales Salvajes/parasitologíaRESUMEN
Plague caused by the Gram-negative bacterium, Yersinia pestis, is still endemic in parts of the world today. Protection against pneumonic plague is essential to prevent the development and spread of epidemics. Despite this, there are currently no licensed plague vaccines in the western world. Here we describe the means of delivering biologically active plague vaccine antigens directly to mucosal sites of plague infection using highly stable microvesicles (outer membrane vesicles; OMVs) that are naturally produced by the abundant and harmless human commensal gut bacterium Bacteroides thetaiotaomicron (Bt). Bt was engineered to express major plague protective antigens in its OMVs, specifically Fraction 1 (F1) in the outer membrane and LcrV (V antigen) in the lumen, for targeted delivery to the gastrointestinal (GI) and respiratory tracts in a non-human primate (NHP) host. Our key findings were that Bt OMVs stably expresses F1 and V plague antigens, particularly the V antigen, in the correct, immunogenic form. When delivered intranasally V-OMVs elicited substantive and specific immune and antibody responses, both in the serum [immunoglobulin (Ig)G] and in the upper and lower respiratory tract (IgA); this included the generation of serum antibodies able to kill plague bacteria. Our results also showed that Bt OMV-based vaccines had many desirable characteristics, including: biosafety and an absence of any adverse effects, pathology or gross alteration of resident microbial communities (microbiotas); high stability and thermo-tolerance; needle-free delivery; intrinsic adjuvanticity; the ability to stimulate both humoral and cell-mediated immune responses; and targeting of primary sites of plague infection.
Asunto(s)
Antígenos Bacterianos/metabolismo , Membrana Externa Bacteriana/metabolismo , Bacteroides thetaiotaomicron/metabolismo , Vacuna contra la Peste/inmunología , Peste/inmunología , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Vesículas Transportadoras/inmunología , Yersinia pestis/fisiología , Administración Intranasal , Animales , Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/genética , Bacteroides thetaiotaomicron/genética , Bioingeniería , Muerte Celular , Células Cultivadas , Microbioma Gastrointestinal/genética , Humanos , Inmunidad Celular , Inmunidad Humoral , Inmunoglobulina A/metabolismo , Inmunoglobulina G/sangre , Macaca , Peste/prevención & control , Vacuna contra la Peste/metabolismo , Proteínas Citotóxicas Formadoras de Poros/genética , Vesículas Transportadoras/metabolismoAsunto(s)
Técnicas de Laboratorio Clínico/normas , Microcefalia/clasificación , Infección por el Virus Zika/clasificación , Infección por el Virus Zika/congénito , Brasil/epidemiología , Humanos , Recién Nacido , Microcefalia/epidemiología , Madres , Estudios Retrospectivos , Centros de Atención Terciaria , Virus Zika/genética , Virus Zika/inmunología , Infección por el Virus Zika/epidemiologíaRESUMEN
OBJECTIVES: To identify potential molecular drivers associated with prognosis and response to treatment in advanced oropharyngeal squamous cell carcinomas (OPSCC). MATERIALS AND METHODS: Thirty-three OPSCC biopsies from untreated Brazilian patients were evaluated for human papilloma virus genotyping, genome wide copy number alterations and gene expression profiling. Data were integrated using CONEXIC algorithm. Validation with TCGA dataset and confirmation by RT-qPCR of candidate genes were performed. RESULTS: High-risk HPV positive cases, detected in 55% of advanced OPSCC, were associated with better outcome. Losses of 8p11.23-p11.22, 14q11.1-q11.2 and 15q11.2, and gains of 11q13.2 and 11q13.2-q13.3 were detected as recurrent alterations. Gains of 3q26.31 and 11q13.2 and losses of 9p21.3 were exclusively detected in HPV-negative tumors. Two clusters of expression profiles were observed, being one composed mostly by HPV positive cases (83%). HPV-positive enriched cluster showed predominantly immune response-related pathways. Integrative analysis identified 10 modulators mapped in 11q13, which were frequently cancer-related. These 10 genes showed copy number gains, overexpression and an association with worse survival, further validated by TCGA database analyses. Overexpression of four genes (ORAOV1, CPT1A, SHANK2 and PPFIA1) evaluated by RT-qPCR confirmed their association with poor survival. Multivariate analysis showed that PPFIA1 overexpression and HPV status are independent prognostic markers. Moreover, SHANK2 overexpression was significantly associated with incomplete response to treatment. CONCLUSION: The integrative genomic and transcriptomic data revealed potential driver genes mapped in 11q13 associated with worse prognosis and response to treatment, giving fundamentals for the identification of novel therapeutic targets in OPSCC.
Asunto(s)
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/terapia , Cromosomas Humanos Par 11 , Oncogenes , Neoplasias Orofaríngeas/genética , Neoplasias Orofaríngeas/terapia , Resultado del Tratamiento , Proteínas Adaptadoras Transductoras de Señales/genética , Alphapapillomavirus/aislamiento & purificación , Carcinoma de Células Escamosas/virología , Mapeo Cromosómico , Femenino , Genómica , Humanos , Masculino , Persona de Mediana Edad , Proteínas del Tejido Nervioso/genética , Neoplasias Orofaríngeas/virología , Pronóstico , TranscriptomaRESUMEN
The introduction of cisplatin to oncology, in the 1970s, marked the onset of the search for novel and improved metal-based anticancer drugs. Polynuclear PtII and PdII complexes with linear alkylamines as bridging ligands are a class of potential antineoplastic agents that have shown promising cytotoxicity against low-prognosis human cancers, such as metastatic breast adenocarcinoma and osteosarcoma. The present study reports an analysis of [µ-N,N'-bis(3-aminopropyl)butane-1,4-diamine-κ4N,N':N'',N''']bis[dichloridoplatinum(II)], [Pt2Cl4(C10H26N4)], denoted Pt2Spm (Spm is spermine), by vibrational spectroscopy coupled to theoretical calculations. Within the latter, the Density Functional Theory (DFT - mPW1PW/6-31G*) and Effective Core Potential (ECP - LANL2DZ) approaches were used, in order to ensure the most accurate representation of the molecule and achieve a maximum agreement with the experimental data. The solid-state geometry of Pt2Spm corresponds to Ci symmetry, displaying 132 vibrational modes. A complete assignment of the experimental vibrational profile of the system was attained through the combined application of complementary Raman, FT-IR and Inelastic Neutron Scattering (INS) techniques. INS allowed an unequivocal identification of the CH2 and NH2 rocking modes, not clearly detected by the optical techniques, while Raman measurements led to a clear discrimination of the Pt-N stretching frequencies from the two distinct Pt-N moieties within the chelate. The metal-to-metal distances calculated for the molecule under study were found to allow the establishment of effective inter- and intrastrand crosslinks with DNA. These results will hopefully help to clarify the mode of action of the compound, at the molecular level, contributing to the development of improved cisplatin-like chemotherapeutic drugs having a higher efficacy and specificity coupled to lower acquired resistance and deleterious side effects.
Asunto(s)
Antineoplásicos/química , Cisplatino/química , Diaminas/química , Platino (Metal)/química , Antineoplásicos/farmacología , Cisplatino/farmacología , Cristalografía por Rayos X , Humanos , Enlace de Hidrógeno , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , VibraciónRESUMEN
The first neutron scattering study on human nucleated cells is reported, addressing the subject of solvent-slaving to a drug by probing intracellular water upon drug exposure. Inelastic and quasi-elastic neutron scattering spectroscopy with isotope labelling was applied for monitoring interfacial water response to the anticancer drug cisplatin, in the low prognosis human metastatic breast cancer cells MDA-MB-231. Optical vibrational data were also obtained for lyophilised cells. Concentration-dependent dynamical changes evidencing a progressive mobility reduction were unveiled between untreated and cisplatin-exposed samples, concurrent with variations in the native organisation of water molecules within the intracellular medium as a consequence of drug action. The results thus obtained yielded a clear picture of the intracellular water response to cisplatin and constitute the first reported experimental proof of a drug impact on the cytomatrix by neutron techniques. This is an innovative way of tackling a drug's pharmacodynamics, searching for alternative targets of drug action.
Asunto(s)
Cisplatino/metabolismo , Matriz Extracelular/metabolismo , Agua/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Línea Celular Tumoral , Cisplatino/farmacología , Sistemas de Liberación de Medicamentos , Matriz Extracelular/efectos de los fármacos , Humanos , Neutrones , Análisis EspectralRESUMEN
BACKGROUND: In the last decades, survival rates in head and neck squamous cell carcinoma (HNSCC) have not changed, with a five-year survival of only 50%. Thus, there is a great need for the identification of new molecular targets and development of novel therapeutic strategies. Cancer-testis antigens (CTAs) are expressed in various types of tumor but rarely in healthy normal tissues. Therefore, they appear as ideal targets for immunotherapy approaches, as well as, unique markers for cancer diagnosis/prognosis. OBJECTIVE: This study evaluated the expression pattern of cancer/testis antigens (CTA) in HNSCC samples and correlated the expression data with the clinicopathological prognostic variables. METHODS: An in silico screening was performed using all CTA genes cataloged on the CTDatabase and the expression of the eight CTA genes (ARMC3, DDX53, FTHL17, GAGE1, MAGEA11, SYCE1, TCP11, and XAGE1) was examined in 89 HNSCC and 20 normal mucosa samples using RT-PCR analysis. RESULTS: GAGE1 (48.3%), XAGE1 (40.4%) and MAGEA11 (19.1%) were frequently and specifically expressed in HNSCC samples and 68.5% of the cases expressed at least one of these antigens. Moreover, GAGE1 and XAGE1 mRNA positivity was significantly associated with the presence of metastasis in the lymph nodes (p=0.038 and p=0.023, respectively) and, by multivariate analysis, male gender (p=0.032), advanced clinical stage (p=0.018) and mRNA positivity for GAGE1 (p=0.010) were independent prognostic factors for overall survival. CONCLUSION: These findings suggest GAGE1 and XAGE1 expressions to be useful as prognostic markers for HNSCC.
Asunto(s)
Antígenos de Neoplasias/metabolismo , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/secundario , Neoplasias de Cabeza y Cuello/patología , Proteínas de Neoplasias/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Antígenos de Neoplasias/genética , Biomarcadores de Tumor/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/cirugía , Femenino , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Proteínas de Neoplasias/genética , Pronóstico , Tasa de SupervivenciaRESUMEN
In order to promote barrier against ultraviolet radiation and increase of mechanical characteristics performance, nanocomposites of recycled polycarbonate/nano-zinc oxide (rPC/nZnO) with different nZnO content were prepared and submitted to doses of gamma-radiation (1050 kGy). The nanocomposites were also exposed to Xenon light source in a weather chamber viewing to evaluate the action of nZnO against ultraviolet light. The rPC/nZnO nanocomposites were characterized by thermogravimetry (TGA), differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD) and infrared spectrometry (FT-IR). There was a progressive reduction of the glass transition temperature (T g) and degradation temperatures, T onset and T max, as function of gamma-radiation dose and nano-zinc oxide content. The lowering of the thermal properties was attributed to the alcoholysis reaction between hydroxyl groups onto the nZnO surface and carbonate linkages of the rPC during the molten state. WAXD revealed a possible chains arrangement (induction of crystallinity) and/or segregation of chains size (scission of rPC chains generating oligomers) associated to the alcoholysis reaction. The action of gamma-radiation as crosslinking agent was not effective. The degree of swelling is zero on account of the stabilization of rPC radicals by oxygen during gamma-radiation exposure. Before exposure to UV light the carbonyl index (CI) show trend to decreasecorroborating the scission of the rPC carbonate bonds. After 100 hours of exposure a recovering of the CI was noticed. The result was associated to the free radicals recombination and esterification reactions. In some extent the combined action of nZnO and gamma-radiation as barrier to UV light was successful.
RESUMEN
Breast cancer is the second most common type of cancer worldwide and the most frequent among women, being the fifth cause of death from neoplastic disease. Since this is an oxidative-stress related neoplasia, it is largely preventable. A dietary isoflavone abundant in soybean - daidzein - is currently being investigated owing to its chemopreventive and/or chemotherapeutic properties towards the human MDA-MB-231 (metastatic, estrogen-unresponsive) and MCF-7 (estrogen-responsive) breast cancer cell lines. Biological assays for evaluation of antitumour and anti-invasive activities were combined with state-of-the-art vibrational microspectroscopy techniques. At 50 and 100 µM concentrations and 48 h incubation time, daidzein was found to induce a marked decrease in cell viability (ca. 50%) for MDA-MB-231 and MCF-7 cells (respectively ca. 50% and 42%) and 40% inhibition of cell migration. MicroRaman analysis of fixed cells upon exposure to this isoflavone unveiled its metabolic impact on both cell lines. Multivariate data analysis (unsupervised PCA) led to a clear discrimination between the control and DAID-exposed cells, with distinctive effects on their biochemical profile, particularly regarding DNA, lipids and protein components, in a cell-dependent way. This is the first reported study on the impact of dietary antioxidants on cancer cells by microRaman techniques.
Asunto(s)
Antioxidantes/farmacología , Isoflavonas/farmacología , Espectrometría Raman , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Estrógenos/metabolismo , Humanos , Células MCF-7 , Estrés Oxidativo/efectos de los fármacos , Análisis de Componente Principal , Glycine max/químicaRESUMEN
Studies of drug-cell interactions in cancer model systems are essential in the preclinical stage of rational drug design, which relies on a thorough understanding of the mechanisms underlying cytotoxic activity and biological effects, at a molecular level. This study aimed at applying complementary vibrational spectroscopy methods to evaluate the cellular impact of two Pt(ii) and Pd(ii) dinuclear chelates with spermine (Pt2Spm and Pd2Spm), using cisplatin (cis-Pt(NH3)2Cl2) as a reference compound. Their effects on cellular metabolism were monitored in a human triple-negative metastatic breast cancer cell line (MDA-MB-231) by Raman and synchrotron-radiation infrared microspectroscopies, for different drug concentrations (2-8 µM) at 48 h exposure. Multivariate data analysis was applied (unsupervised PCA), unveiling drug- and concentration-dependent effects: apart from discrimination between control and drug-treated cells, a clear separation was obtained for the different agents studied - mononuclear vs. polynuclear, and Pt(ii) vs. Pd(ii). Spectral biomarkers of drug action were identified, as well as the cellular response to the chemotherapeutic insult. The main effect of the tested compounds was found to be on DNA, lipids and proteins, the Pd(ii) agent having a more significant impact on proteins while its Pt(ii) homologue affected the cellular lipid content at lower concentrations, which suggests the occurrence of distinct and unconventional pathways of cytotoxicity for these dinuclear polyamine complexes. Raman and FTIR microspectroscopies were confirmed as powerful non-invasive techniques to obtain unique spectral signatures of the biochemical impact and physiological reaction of cells to anticancer agents.
Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Cisplatino/farmacología , Espectrofotometría Infrarroja , Espectrometría Raman , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Biomarcadores/metabolismo , Línea Celular Tumoral , Humanos , Espermina/metabolismo , Neoplasias de la Mama Triple Negativas/patología , VibraciónRESUMEN
In this study, thin LbL films were produced by combining the adhesive properties of the hyaluronic acid-dopamine conjugate with the bioactivity and bactericidal properties of silver doped bioactive glass nanoparticles. The build-up of these films was investigated by quartz crystal microbalance with dissipation monitoring. LbL coatings were then constructed on a glass substrate for further characterization. We found that these antimicrobial bioinspired films display enhanced adhesive strength. In vitro bioactivity tests were performed by immersing them in simulated body fluid solution for 14 days where the constructed films promoted the formation of a bone-like apatite layer. From microbiological assays, it was found that coatings containing silver doped nanoparticles exhibited a remarkable antibacterial effect against Staphylococcus aureus and Escherichia coli cultures. Finally, in vitro cellular behavior tests showed enhanced cell adhesion, proliferation and viability for these antibacterial bioadhesive films. Therefore, the constructed thin films showed promising properties and evidenced great potential to be used as coatings for orthopedic implants.
RESUMEN
PURPOSE: Activation of proto-oncogenes and inactivation of tumour suppressor genes are the major genetic alterations involved in carcinogenesis. The increase in methylation at the promoter region of a tumour suppressor gene can lead to gene inactivation, selecting cells with proliferative advantage. Thus, promoter hypermethylation is considered a marker in a variety of malignant tumours, including oral cavity. EXPERIMENTAL DESIGN: The methylation pattern of eight genes was evaluated in 40 oral cavity squamous cell carcinomas (OSCCs) and 40 saliva samples from healthy individuals by Q-MSP. Different combinations of genes were also assessed in order to identify gene panels that could better distinguish between OSCC and saliva samples. RESULTS: CCNA1, DAPK, DCC and TIMP3 methylation were highly specific for being found in the OSCC samples. Moreover, the combination of these genes improved detection when compared with single markers, reaching values of 92.5% for sensitivity and specificity (when using the panel CCNA1, DCC, TIMP3). Moreover, DAPK, DCC and TIMP3 were hypermethylated in nearly 90% of clinically T1 and T2 cases. CONCLUSION: The pursuing of this panel of hypermethylated genes is an important tool for the detection of individuals with OSCC. Moreover, the identification of these markers in early stages of OSCC shows the feasibility of using the panel on saliva as possible biomarkers for early diagnosis. The lack of association between the methylation status of these genes and clinical characteristics shows that they are able to distinguish OSCC cases irrespective of social and clinical factors (gender, age, human papillomavirus (HPV) status, clinical stage, vascular embolisation and perineural invasion).