Investigação dos efeitos das impurezas alcalinas e hidrogênio no quartzo submetido à eletrodifusão e radiação ionizante

Pós-graduação em Ciência dos Materiais - FEIS

Reproductive toxicology and clastogenic evaluation in mice of a phytotherapeutic formulation obtained from Cinchona calisaya Weddel (Rubiaceae) used in Brazilian folk medicine as female fertility stimulant

Ethnopharmacological relevance: In Brazil, a phytotherapeutic preparation produced from a standardized tincture of Cinchona calisaya Weddel such that each mL of product contains 400 mu g of quinine, known in Portuguese as Agua Inglesa (R) (English water), is indicated by the manufacturer as a tonic, appetite stimulant, and digestive. However, this preparation has long been used in folk medicine as a female fertility stimulant. Despite its widespread use in folk medicine to stimulate female fertility, no study has been undertaken to assess the potential teratogenic and genotoxic effects of this phytotherapeutic preparation. The aim of the present study was to investigate possible toxic reproductive effects in mice caused by exposure to Agua Inglesa (R), either before mating or during the pre- and post-embryo implantation periods. The genotoxic potential was evaluated using the micronucleus assay.Material, Methods, and Results: Virgin female mice, with at least one estrous cycle evidenced by vaginal cytology, were divided into five groups of 15 individuals each (Group I - control, Group II - treated with ethanol solution at 16%, Groups III, IV and V treated with phytotherapeutic preparation at 1.5 mL/kg/day, 3.0 mL/kg/day and 4.5 mL/kg/day, respectively). After the first 28 days of treatment, females were caged individually with adult fertile males. Pregnant females continued to receive treatment for seven days (preimplantation period). Body weight was recorded weekly during treatment. Signs of toxicity (weight loss, food intake, piloerection, apathy, prostration, diarrhea, seizures, behavioral changes, and locomotion) were also observed. The females were sacrificed on the 15th day of pregnancy, uterine horns were evaluated for implantation, and the placental index was recorded. In the micronucleus test, 2000 polychromatic erythrocytes (PCE) per animal, obtained from bone marrow, were scored. Results The results showed that exposure of the females during the pre- and post-implantation periods did not significantly alter the reproductive capacity (p < 0.05); however, in higher dose (three times human dose)reduction of fetal weight was observed. There was no difference between the control and phytotherapeutic preparation (p > 0.05) in terms of the average number of micronucleated polychromatic erythrocytes.Conclusions: Although folk medicine suggests that the Agua Inglesa (R) preparation is useful as a female fertility stimulant, no such effect was confirmed in mice. (C) 2014 Elsevier Ireland Ltd. All rights reserved.

Controle de qualidade em equipamentos mamográficos

Nowadays the mammography is the most effective way of revealing early breast cancer. The image in this kind of exam is gotten trough a x-ray sheaf of low energy, however, the suitable visualization of the interesting structures by the radiologist is not always possible due several factors that appears since the mamma composition until the equipments limitation. The regulation 453/98 sets quality control tests and limits of acceptation that guarantee a good development of the mammographys. The purpose of this study is the 3D principle ( Diagnostic, Dose and Dollar), that means, an improved diagnosis, a dose reduction in the patient and a cost decrease for the Institution. In this study was made the quality control tests set by the Regulation in two mammography equipments from Hospital das Clínicas da Faculdade de Medicina de Botucatu (HCFMB - UNESP). The results reached in this research were used in the renovation process of quality stamp in mammography granted by Colégio Brasileiro de Radiologia (CBR) to the diagnosis by image from the HCFMB – UNESP

Dosimetria Física e Controle de Qualidade em Radioterapia

Radiotherapy is a multidisciplinary speciality which uses complex equipment and radiation sources for delivery of treatment, using high-energy ionizing radiation to treat cancer at several stages of complexity. Since radiation therapy is a technique which involves a precalculated radiation dose, it shall be established quality assurance programs that provide an efficient and safety treatment. The International Commission on Radiation Units and Measurements (ICRU) report No. 50 has recommended dose uniformity between 5% of the prescribed dose throughout the region of interest. This is one of the most primordial points that justify the importance of a suitable attendance of the equipments quality and performance. For quality control, the medical physicist will be involved with establishing and running a Quality Control Program (QCP). He must adapt or develop the procedures of equipment acceptance and commissioning, besides verifying the use of principles and accepted protocols of national and international reports to assure the correct quality, quantity, and placement of radiation during the performance of a radiological procedure, establishing adequate protocols to ensure accurate patient dosimetry. This present work consists of a description of the activities carried through the Sectors of Radiation Therapy of the Hospital of Clinics of the Campinas State University (Unicamp), particularly in the implementation of the Quality Control Program

Estudo para determinação da kVp em equipamentos de raios X convencional

The quality assurance control program (QACP) in clinical radiology is very important to acquire, image quality, patient dose reduction and cost for the institution. The verification of the real tension on the x ray tube, it is one of many parameters that may be determined on a QACP. This act on image quality as absorbed dose in patient. Once proved the importance of this fact, this study come up with the determination of tension to any X ray tube used on medical routine, on quick, safe and low cost manner. To reach the aim of this study, the methodology consisted on measuring expose rates (ER) using different thicknesses of copper (Cu) plates like filters and relating these results with Half Layer Value (HLV). Afterwards, the HLV was associated to real tension that was acquired with kilo voltage of peak (kVp) measurers used on clinical routine. So walking in this path, when performed the ER, on any X ray tube, it’s possible acquire the HLV and consequently the real kVp, considering measures obtained before, on the methodology of kVp estimative development

Radioterapia em câncer de mama: importância da determinação da curva de isodose

The study analyzed contours of the thoracic region of patients undergoing radiotherapy of breast tumors in Hospital Manuel de Abreu of Bauru (institution 1) and the Hospital da Faculdade de Medicina of Botucatu (Institution 2). Were prepared isodose curves corresponding to the contours of the patient, which were presented for radiotherapists doctors both hospital services that enabled the choice of the curve isodose that provides the best distribution of radiation dose in the irradiated volume. Some boundaries were digitized in one institution and sent for preparation of isodose lines in the institution 2, both curves plotted in each of the institutions and for the same contour, were compared, showing that the methodology of Curves of distance is feasible and reliable, while optimizing the routine procedures regarding the handling of isodose plans provided by different radiation equipment. It compares the calculation of the exposure time determined using the isodose curve selected by calculating the value obtained considering the PDP at the point of the middle line of separation between the internal and external fields, the difference between the two methods for determining exposure time was around 2.4%. A study on the angle of the radiation beam at the input field (region breast-air) was conducted showing that, once known a tangent angle of the input beam, one can estimate the angle of the wedge filter used in some procedures for uniformity of dose within the irradiated volume compensation and the lack of tissue in the treatment volume. A comparative study between the isodose curves produced manually with the curves obtained in a two-dimensional computer system, the computer system showed that provides further information regarding the dose gradient within the irradiated volume, in addition to reducing the time spent in preparing the curves isodose

Diagnóstico e planejamento em cirurgia parendodôntica: utilização da tomografia cone beam

The ability to tridimensionally evaluate pathological and anatomical areas, in apical surgery planning, presents a number of advantages. Cone beam computed tomography (CBCT) was developed for dental applications. This paper aims to present a literature review on CBCT, highlighting its advantages over both conventional computed tomography (CT) and radiography. Moreover, its clinical applications in apical surgery are discussed. LITERATURE REVIEW AND CONCLUSION: Unlikely CT, CBCT captures a volume of data in a single 360º rotation, providing benefits such as higher accuracy, better resolution, reduced scanning time and reduced radiation dose. In the maxillofacial region, CBCT has been mainly used in the assessment of dento-alveolar pathology and oral traumatology. CBCT provides a better diagnosis and quantitative information on periodontal bone levels than conventional radiography. It has also been used for patients requiring surgical facial reconstruction, orthognathic surgery, dental implants, and more complex tooth extractions. Besides that, it seems to be a significant tool in modern endodontic practice, presenting useful applications in apical surgery.

Mutagenic potential of lettuce grown from irradiated seeds

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Ra-226 and Ra-228 in mineral waters of southeast Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effects of copper vapor laser irradiation (λ = 510.6 nm) on the enamel and dentine of human teeth: An ultra-structural morphologic study

Objective: A morphological and ultra-structural study of copper vapor laser (λ = 510.6 nm) effects on enamel and dentine was performed to show the effects of this radiation. Methods: A total of 15 human molars were cut in half; 15 pieces were separated for irradiation on enamel and 15 for dentine. These two groups were further divided into five experimental groups, including a control group, comprised of three half-sections each, irradiated by a CVL laser with a power of 7 W, a repetition rate of 15,000 pulses/sec and exposed at 500, 600, and 800 msec and 1 sec irradiation times with a 5-sec interval between irradiations. Results: In an ultra-structural SEM exam, we observed that on the enamel surfaces irradiated for 1 sec there was morphological alteration that consisted of catering, flaking, and melting on the surfaces. There was no alteration for the other exposure times. On the dentine teeth irradiated for 1 sec, we observed an evident ultra-structural alteration of melted tissue and loss of morphological characteristics. In the dentine group irradiated by 800 msec, we observed ablation and a partial loss of morphological characteristics. In the dentine groups irradiated by 500 and 600 msec, no alteration was observed. Conclusions: The results showed that irradiation with CVL promoted morphologic changes in the enamel as well as in the dentine and demonstrated a need for future studies in order to establish a safe protocol for further use in the odontological practice.

325 degrees C thermoluminescence peak growth in quartz related to oxygen vacancies

The thermoluminescence intensity as a function of gamma-ray dose of the 325 degreesC peak, in quartz grains extracted from sea sediments and from fluvial aeolic dunes, is studied. It is found that the response curve at low doses has a concavity directed opposite to that of quartz grains extracted from archaeological potteries. To explain this behavior a model is proposed here based on oxygen vacancies and [AlO4/h](0) centers. The experimentally observed ESR intensity of E-I'-centers as a function of radiation dose can also be explained by this model.

Patients from the Oral Oncology Center, UNESP, Araçatuba with an indication for prosthesis

Head and neck tumors are a major health concern worldwide, due to their high incidence and mortality rates, particularly in developing countries. In Brazil, this type of cancer is commonly diagnosed and studies suggested that it may be the leading cause of mortality in the country. The increase in life expectancy worldwide, as well as environmental and behavioral factors, are related to carcinogenesis. Therefore, an understanding of basic epidemiology and statistical methods is critical, in order to promote early diagnosis and cancer prevention. Cancer patients with an indication for prosthesis were selected from the medical records of the Oral Oncology Center, School of Dentistry, São Paulo State University (UNESP), Araçatuba, between 1991 and 2010. The following variables were recorded: gender, age, type and location of the lesion, radiation dose and dental prosthesis. The majority of the patients were male (74.15%) and >60 years of age (53.37%). Tumors were most commonly located in the floor of the mouth (11.1%) and squamous cell carcinoma was the most prevalent type (72.8%). This study provides the profiles of patients who attended the Oral Oncology Center and the results may aid in the creation of cancer prevention programs.

Quantification of pulmonary inflammatory processes using chest radiography: tuberculosis as the motivating application

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Reduction of crotoxin-induced neuromuscular blockade by gamma radiation

A comparative study between crotoxin and gamma irradiated crotoxin was performed on the indirectly evoked twitches and tetani of sciatic nerve-extensor digitorum longus muscle of rats. Crotoxin (3 to 14 mu g/ml) decreased the amplitude of twitches and induced a slight tetanic fade, and irradiated crotoxin did not significantly affect either twitch amplitude or tetanic tension. Since gamma radiation reduced the neurotoxicity of crotoxin it may be useful for the production of anticrotalic serum. (C) 1998 Elsevier B.V. Ltd. All rights reserved.

Poly [1,1'-bis(ethynyl)-4,4'-biphenyl(bis-tributylphosphine)Pt(II)] solutions used as low dose ionizing radiation dosimeter

In this work, the effect of gamma radiation on the optical properties of polymetallayne poly[1,1'-bis(ethynyl)-4,4'-biphenyl(bis-tributylphosphine)Pt(II) ] (Pt-DEBP) in chloroform solution is studied. The samples were irradiated at room temperature with doses from 0.01 Gy to 1 Gy using a 60Co gamma ray source. A new band at 420 nm is observed in the emission spectra, in superposition to the emission maximum at 398 nm, linearly dependent on dose. We propose to use the ratio of the emission amplitude bands as the dosimetric parameter. This method proved to be robust, accurate, and can be used as a dosimeter in medical applications. © 2013 AIP Publishing LLC.