Análise molecular dos éxons 8 a 11 do gene da p53 em amostras de câncer de colo de útero no Rio Grande do Norte

Mutations on TP53 gene are common in human cancer but not in cervical cancer where they are rarely found and the inactivation and degradation of p53 protein are attributed to the action of E6 viral oncogene from high risk human papillomavirus (HPV). Analysis of cervical cancer cell lines suggests that HPV negative samples shows mutation on TP53, but clinical approaches didn t confirmed this hypothesis. However, in most TP53 mutations studies on cervical cancer, only the exons 5 to 8 were analyzed. Approximately 90% of mutations described are on this region. Recent studies on several cancer suggests that mutation frequency in the other exons must be considered. The aim of this work was to verify whether mutations on coding and non-coding regions occur in cancer tissue from cervical cancer in patients from Rio Grande do Norte using Denaturing Gradient Gel Electrophoresis (DGGE) as screening tool. Exons 8 to 11 were analyzed including some introns from 80 tumor samples and 8 peripheral blood samples from healthy women. DNA were submitted to PCR using primers with GC clamp on the end of one of them. The results were observed for each region after DGGE and silver staining. It was observed no amplified fragment with different migration profile from those obtained from DNA of peripheral blood. These results agree with those from literature where TP53 mutations in cervical cancer have been described in a very low frequency

miRNAS circulantes como biomarcadores para fibrilação atrial aguda

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. Some non-coding RNAs (miRNAs) have been involved in regulatory activity in arrhythmogenesis, targeting genes that contribute to the development of AF. The present study aimed to evaluate the expression of candidate miRNAs in plasma from patients with AF and new-onset AF and its application as future markers for diagnosis and monitoring of disease. miR-21, miR-133a, miR-133b, miR-150, miR-328 and miR-499 were selected as targets in this study through a prior literature review. They were isolated from plas-ma of individuals aged from 20 to 85 years old with AF (n = 17), new-onset AF (n = 5) and without AF (n = 15), where the latter was the control group. The results were ana-lyzed by Real-Time PCR (RT-PCR) with miScript SYBR Green PCR. We observed that miR-21, miR-133b, miR-328 and miR-499 had different levels of expression be-tween the three groups (p <0.05). Increased expression of miR-21 (0.6-fold), miR-133b (1.4-fold), miR-328 (2.0-fold) and miR-499 (2.3-fold) in patients with new-onset AF when compared to AF and control subjects. The miR-133a and miR-150 expression did not differ among the groups. miR-21, miR-133b, miR-328 and miR-499 may be potential biomarkers for AF as well as for new-onset AF, for monitoring and for the di-agnosis. These findings may contribute to the understanding of the process that trig-gers AF and suggest application these molecules as future biomarkers for AF.

miRNAS circulantes como biomarcadores para fibrilação atrial aguda

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. Some non-coding RNAs (miRNAs) have been involved in regulatory activity in arrhythmogenesis, targeting genes that contribute to the development of AF. The present study aimed to evaluate the expression of candidate miRNAs in plasma from patients with AF and new-onset AF and its application as future markers for diagnosis and monitoring of disease. miR-21, miR-133a, miR-133b, miR-150, miR-328 and miR-499 were selected as targets in this study through a prior literature review. They were isolated from plas-ma of individuals aged from 20 to 85 years old with AF (n = 17), new-onset AF (n = 5) and without AF (n = 15), where the latter was the control group. The results were ana-lyzed by Real-Time PCR (RT-PCR) with miScript SYBR Green PCR. We observed that miR-21, miR-133b, miR-328 and miR-499 had different levels of expression be-tween the three groups (p <0.05). Increased expression of miR-21 (0.6-fold), miR-133b (1.4-fold), miR-328 (2.0-fold) and miR-499 (2.3-fold) in patients with new-onset AF when compared to AF and control subjects. The miR-133a and miR-150 expression did not differ among the groups. miR-21, miR-133b, miR-328 and miR-499 may be potential biomarkers for AF as well as for new-onset AF, for monitoring and for the di-agnosis. These findings may contribute to the understanding of the process that trig-gers AF and suggest application these molecules as future biomarkers for AF.

Pirólise termoquímica de pós da fibra de coco seco em um reator de cilindro rotativo para produção de bio-óleo

This master thesis aims at developing a new methodology for thermochemical degradation of dry coconut fiber (dp = 0.25mm) using laboratory rotating cylinder reactor with the goal of producing bio-oil. The biomass was characterized by infrared spectroscopy with Fourier transform FTIR, thermogravimetric analysis TG, with evaluation of activation energy the in non-isothermal regime with heating rates of 5 and 10 °C/min, differential themogravimetric analysis DTG, sweeping electron microscopy SEM, higher heating value - HHV, immediate analysis such as evaluated all the amounts of its main constituents, i.e., lignin, cellulose and hemicelluloses. In the process, it was evaluated: reaction temperature (450, 500 and 550oC), carrier gas flow rate (50 and 100 cm³/min) and spin speed (20 and 25 Hz) to condensate the bio-oil. The feed rate of biomass (540 g/h), the rotation of the rotating cylinder (33.7 rpm) and reaction time (30 33 min) were constant. The phases obtained from the process of pyrolysis of dry coconut fiber were bio-oil, char and the gas phase non-condensed. A macroscopic mass balance was applied based on the weight of each phase to evaluate their yield. The highest yield of 20% was obtained from the following conditions: temperature of 500oC, inert gas flow of 100 cm³/min and spin speed of 20 Hz. In that condition, the yield in char was 24.3%, non-condensable gas phase was 37.6% and losses of approximately 22.6%. The following physicochemical properties: density, viscosity, pH, higher heating value, char content, FTIR and CHN analysis were evaluated. The sample obtained in the best operational condition was subjected to a qualitative chromatographic analysis aiming to know the constituents of the produced bio-oil, which were: phenol followed by sirigol, acetovanilona and vinyl guaiacol. The solid phase (char) was characterized through an immediate analysis (evaluation of moisture, volatiles, ashes and fixed carbon), higher heating value and FTIR. The non-condensing gas phase presented as main constituents CO2, CO and H2. The results were compared to the ones mentioned by the literature.

Desenvolvimento de uma unidade laboratorial para quantificação de BTX como poluentes atmosféricos, usando microextração em fase sólida

This dissertation aims the development of an experimental device to determine quantitatively the content of benzene, toluene and xylenes (BTX) in the atmosphere. BTX are extremely volatile solvents, and therefore play an important role in atmospheric chemistry, being precursors in the tropospheric ozone formation. In this work a BTX new standard gas was produced in nitrogen for stagnant systems. The aim of this dissertation is to develop a new method, simple and cheaper, to quantify and monitor BTX in air using solid phase microextraction/ gas chromatography/mass spectrometry (SPME/CG/MS). The features of the calibration method proposed are presented in this dissertation. SPME sampling was carried out under non-equilibrium conditions using a Carboxen/PDMS fiber exposed for 10 min standard gas mixtures. It is observed that the main parameters that affect the extraction process are sampling time and concentration. The results of the BTX multicomponent system studied have shown a linear and a nonlinear range. In the non-linear range, it is remarkable the effect of competition by selective adsorption with the following affinity order p-xylene > toluene > benzene. This behavior represents a limitation of the method, however being in accordance with the literature. Furthermore, this behavior does not prevent the application of the technique out of the non-linear region to quantify the BTX contents in the atmosphere.

Pirólise termoquímica de pós da fibra de coco seco em um reator de cilindro rotativo para produção de bio-óleo

This master thesis aims at developing a new methodology for thermochemical degradation of dry coconut fiber (dp = 0.25mm) using laboratory rotating cylinder reactor with the goal of producing bio-oil. The biomass was characterized by infrared spectroscopy with Fourier transform FTIR, thermogravimetric analysis TG, with evaluation of activation energy the in non-isothermal regime with heating rates of 5 and 10 °C/min, differential themogravimetric analysis DTG, sweeping electron microscopy SEM, higher heating value - HHV, immediate analysis such as evaluated all the amounts of its main constituents, i.e., lignin, cellulose and hemicelluloses. In the process, it was evaluated: reaction temperature (450, 500 and 550oC), carrier gas flow rate (50 and 100 cm³/min) and spin speed (20 and 25 Hz) to condensate the bio-oil. The feed rate of biomass (540 g/h), the rotation of the rotating cylinder (33.7 rpm) and reaction time (30 33 min) were constant. The phases obtained from the process of pyrolysis of dry coconut fiber were bio-oil, char and the gas phase non-condensed. A macroscopic mass balance was applied based on the weight of each phase to evaluate their yield. The highest yield of 20% was obtained from the following conditions: temperature of 500oC, inert gas flow of 100 cm³/min and spin speed of 20 Hz. In that condition, the yield in char was 24.3%, non-condensable gas phase was 37.6% and losses of approximately 22.6%. The following physicochemical properties: density, viscosity, pH, higher heating value, char content, FTIR and CHN analysis were evaluated. The sample obtained in the best operational condition was subjected to a qualitative chromatographic analysis aiming to know the constituents of the produced bio-oil, which were: phenol followed by sirigol, acetovanilona and vinyl guaiacol. The solid phase (char) was characterized through an immediate analysis (evaluation of moisture, volatiles, ashes and fixed carbon), higher heating value and FTIR. The non-condensing gas phase presented as main constituents CO2, CO and H2. The results were compared to the ones mentioned by the literature.