Quantification of Biological Tissue and Construction of Patient Equivalent Phantom (Skull and Chest) for Infants (1-5 years old)

Our main purpose in this study was to quantify biological tissue in computed tomography (CT) examinations with the aim of developing a skull and a chest patient equivalent phantom (PEP), both specific to infants, aged between 1 and 5 years old. This type of phantom is widely used in the development of optimization procedures for radiographic techniques, especially in computed radiography (CR) systems. In order to classify and quantify the biological tissue, we used a computational algorithm developed in Matlab (R). The algorithm performed a histogram of each CT slice followed by a Gaussian fitting of each tissue type. The algorithm determined the mean thickness for the biological tissues (bone, soft, fat, and lung) and also converted them into the corresponding thicknesses of the simulator material (aluminum, PMMA, and air). We retrospectively analyzed 148 CT examinations of infant patients, 56 for skull exams and 92 were for chest. The results provided sufficient data to construct a phantom to simulate the infant chest and skull in the posterior anterior or anterior posterior (PA/AP) view. Both patient equivalent phantoms developed in this study can be used to assess physical variables such as noise power spectrum (NPS) and signal to noise ratio (SNR) or perform dosimetric control specific to pediatric protocols.

Evaluation of the biocompatibility of silicone gel implants - histomorphometric study

Breast implants are medical devices that are used to augment breast size or to reconstruct the breast following mastectomy or to correct a congenital abnormality. Breast implants consist of a silicone outer shell and a filler (most commonly silicone gel or saline). Approximately 5 to 10 million women worldwide have breast implants. Histomorphometric study to evaluate the biological tissue compatibility of silicone implants suitable for plastic surgery and the adverse effects and risks of this material. Thirty Wistar white rats received subcutaneous implants and the revestiment of silicone gel Silimed ®®, and randomized into six groups of five animals each, according to the type of implanted material and the time of sacrifice. Eight areas of 60.11mm2 corresponding to the obtained surgical pieces were analyzed, counting mesenchymal cells, eosinophils, and foreign body giant cells, observing an acceptable biocompatibility in all implants, for subsequent statistical analysis by Tukey test. Silicone gel showed inflammation slightly greater than for other groups, with tissue reactions varying from light to moderate, whose result was the formation of a fibrous capsule around the material, recognized by the organism as a foreign body. Despite frequent local complications and adverse outcomes, this research showed that the silicone and top layer presented an acceptable chronic inflammatory reaction, which did not significantly differ from the control group. In general, it is possible to affirm that silicone gel had acceptable levels of biocompatibility, confirmed the rare presence of foreign body giant cells, and when of the rupture, formed a fibrous capsule around the material, separating the material of the organism. © AVICENA 2013.

Balancing guava nutrition with liming and fertilization

A resposta da goiabeira à calagem e à adubação pode ser monitorada por análises de tecido vegetal. O perfil nutricional é definido em relação a padrões de teores de nutrientes. No entanto, os teores de nutrientes-padrão são constantemente criticados por não considerarem as interações que ocorrem entre nutrientes e por gerarem tendências numéricas, decorrentes da redundância dos dados, da dependência de escala e da distribuição não normal. As técnicas de análise composicional de dados podem controlar esses dados tendenciosos, equilibrando os grupos de nutrientes, tais como os envolvidos na calagem e na adubação. A utilização das relações log isométricas (ilr) ortonormais, sequencialmente dispostas, evita tendências numéricas inerentes aos dados de composição. Os objetivos do trabalho foram relacionar o balanço de nutrientes dos tecidos vegetais com a produção de goiabeiras em pomares de 'Paluma' diferentemente corrigidos e adubados, e ajustar os atuais padrões de nutrientes com a faixa de equilíbrio das goiabeiras mais produtivas. Um experimento de calagem de sete anos e três, experimentos de três anos com doses de N, P2O5 e K2O, foram conduzidos em pomares de goiabeiras 'Paluma' em um Latossolo Vermelho-Amarelo. Os teores de N, P, K, Ca e Mg na planta foram monitorados anualmente. Selecionaram-se os balanços [N, P, K | Ca, Mg], [N, P | K], [N | P] e [Ca | Mg] para separar os efeitos da calagem (Ca-Mg) e dos fertilizantes (N-K) nos balanços de macronutrientes. Os balanços foram mais influenciados pela calagem do que pela fertilização. A produtividade das goiabeiras e seu balanço nutricional permitiram a definição de faixas de equilíbrio de nutrientes e sua validação com as faixas de concentrações críticas atualmente utilizadas no Brasil e combinadas em coordenadas ilr.

New alternative for human identification. Investigator IDplex Kit - QIAGEN® reproducibility: Latin American interlaboratory study

In 2010 QIAGEN® launched to eight kits of different combinations of STRs, including the Investigator IDplex Kit. This kit allows amplification in one PCR 16 markers. The aim of this study was to evaluate the reproducibility of Investigator IDplex Kit among Latin America laboratories. In the framework of the 'III International Theoretical-Practice Course in Populations Genetic and Biologicals Filiations' in Medellín-Colombia, all participants were invited to evaluate the reproducibility of this kit, they were provided of the necessary materials for the study. The results reported by participating were tabulated for the study the reproducibility. Results and comments were received on the agreed date of 12 of the 22 laboratories registered, one participant submits comments only. Some laboratories reported greater sensitivity Investigator IDplex Kit compared with other kits containing similar markers, also highlight the easy adaptability to existing conditions in laboratories, without involving major changes to its implementation. This paper shows the high reproducibility of Investigator IDplex Kit, a new tool offered by QIAGEN® for all laboratories that perform human identification testing and biological relationship testing using DNA markers. © 2011 Elsevier B.V.

Unbiased approach to diagnose the nutrient status of red guava (Psidium guajava)

Fertilization of guava relies on soil and tissue testing. The interpretation of tissue test is currently conducted by comparing nutrient concentrations or dual ratios with critical values or ranges. The critical value approach is affected by nutrient interactions. Nutrient interactions can be described by dual ratios where two nutrients are compressed into a single expression or a ternary diagrams where one redundant proportion can be computed by difference between 100% and the sum of the other two. There are D(D-1) possible dual ratios in a D-parts composition and most of them are thus redundant. Nutrients are components of a mixture that convey relative, not absolute information on the composition. There are D-1 balances between components or ingredients in any mixture. Compositional data are intrinsically redundant, scale dependent and non-normally distributed. Based on the principles of equilibrium and orthogonality, the nutrient balance concept projects D-1 isometric log ratio (ilr) coordinates into the Euclidean space. The D-1 balances between groups of nutrients are ordered to reflect knowledge in plant physiology, soil fertility and crop management. Our objective was to evaluate the ilr approach using nutrient data from a guava orchard survey and fertilizer trials across the state of São Paulo, Brazil. Cationic balances varied widely between orchards. We found that the Redfield N/P ratio of 13 was critical for high guava yield. We present guava yield maps in ternary diagrams. Although the ratio between nutrients changing in the same direction with time is often assumed to be stationary, most guava nutrient balances and dual ratios were found to be non-stationary. The ilr model provided an unbiased nutrient diagnosis of guava. © ISHS.

Desenvolvimento e construção de fantomas homogêneos pediátricos para otimização de imagens radiográficas de tórax

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

Resposta imuno-bioquímica e avaliação histológica da cartilagem articular de ratos artrose induzidos, frente ao tratamento com iontoforese isolada e de ácido L-ascorbico

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Low-intensity laser therapy effect on the recovery of traumatic spinal cord injury

Scientific advances have been made to optimize the healing process in spinal cord injury. Studies have been developed to obtain effective treatments in controlling the secondary injury that occurs after spinal cord injury, which substantially changes the prognosis. Low-intensity laser therapy (LILT) has been applied in neuroscience due to its anti-inflammatory effects on biological tissue in the repairing process. Few studies have been made associating LILT to the spinal cord injury. The objective of this study was to investigate the effect of the LILT (GaAlAs laser-780 nm) on the locomotor functional recovery, histomorphometric, and histopathological changes of the spinal cord after moderate traumatic injury in rats (spinal cord injury at T9 and T10). Thirty-one adult Wistar rats were used, which were divided into seven groups: control without surgery (n = 3), control surgery (n = 3), laser 6 h after surgery (n = 5), laser 48 h after surgery (n = 5), medullar lesion (n = 5) without phototherapy, medullar lesion + laser 6 h after surgery (n = 5), and medullar lesion + laser 48 h after surgery (n = 5). The assessment of the motor function was performed using Basso, Beattie, and Bresnahan (BBB) scale and adapted Sciatic Functional Index (aSFI). The assessment of urinary dysfunction was clinically performed. After 21 days postoperative, the animals were euthanized for histological and histomorphometric analysis of the spinal cord. The results showed faster motor evolution in rats with spinal contusion treated with LILT, maintenance of the effectiveness of the urinary system, and preservation of nerve tissue in the lesion area, with a notorious inflammation control and increased number of nerve cells and connections. In conclusion, positive effects on spinal cord recovery after moderate traumatic spinal cord injury were shown after LILT.

Terapia fotodinâmica e luz branca: aspectos analíticos e perspectivas da viabilidade do tratamento

Photodynamic Therapy (PDT) is a technique used to treat several types of lesions, such as cancer, microbial control, and esthetic dentistry cases. The performance of PDT involves the use of a photosensitizer (PS), which mainly will be located in cancer cells and is irradiated with visible light. This process, when it occurs in the presence of oxygen triggers the formation of reactive oxygen species that are cytotoxic to cells. These species cause cell death and subsequent tumor necrosis. The use of white light as a light source for multispectral Photodynamic Therapy and its consequences to the photodynamic effect is not yet completely established, and therefore there is interest in studying the parameters involved for analyzing the best conditions for applying treatment. The wavelength is crucial to improve the therapeutic effect, since both the optical properties of the biological tissue as the PS depend on these parameters. For FS studied in this work (Photogem®) are most often used wavelengths in the red region, due to their larger penetration depth in biological tissue. Thus, the light source becomes a fundamental aspect, their choice depends on the specific application and is based on the tumor location, light dose to be delivered and FS chosen. Despite all the advantages presented by lasers, the fact of having an emission spectrum essentially monochrome makes only one possible transition possible for the absorption of FS is used. Therefore, more extensive light sources such as light emitting diodes (LED), could be better used in some cases the laser, with the additional advantage of a reduced cost. Therefore, the choice of the white LED comes from an emission spectrum that still wider LED colors defined by allowing greater use of the several absorption bands and with varying depths of operation, according to the wavelength... (Complete abstract click electronic access below)

Classificação e quantificação de tecidos Biológicos para construção de fantomas pediátricos

Paediatric diagnostic radiology can be considered as a separate specialty and with distinct characteristics of the radiology applied in adult patients. This in reason of the variability in the anatomical structures size and bigger sensitivity of tissues. The literature present in its majority methodologies for segmentation and tissue classification in adult patients, and works on tissue quantification are rare. This work had for objective the development of a biological tissue classifier and quantifier algorithm, from histograms, and that converts the quantified average thickness of these tissues for its respective simulator materials. The results will be used in the optimization process of paediatrics images, in future works, since these patients are frequently over exposed to the radiation in the repeated attempts of if getting considered good quality radiographic images. The developed algorithm was capable to read and store the name of all the archives, in the operational system, to filter artifacs, to count and quantify each biological tissues from the histogram of the examination, to obtain the biological tissues average thicknesses and to convert this value into its respective simulator material. The results show that it is possible to distinguish bone, soft, fat and pulmonary tissues from histograms of tomographic examinations of thorax. The quantification of the constituent materials of anthropomorphic phantom made by the algorithm, compared with the data of literature shows that the biggest difference was of 21,6% for bone. However, the literature shows that variations of up to 30% in bone thickness do not influence of significant form in the radiographic image quality. The average thicknesses of biological tissues, quantified for paediatrics patients, show that one phantom can simulate patients with distinct DAP ranges, since variations... (Complete abstract click electronic access below)

Construção de fantomas homogêneos pediátricos de crãnio e tórax para otimização de imagens em radiografia computadorizada

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação da biocompatibilidade de implantes de silicone gel em subcutâneo de ratos: estudo histomorfométrico

Objective: Histomorphometric study to evaluate the biological tissue compatibility of silicone implants suitable for plastic surgery. Methods: Thirty Wistar white rats received subcutaneous implants ande the revestiment of silicone gel Silimed, and randomized into six groups of five animals each, according to the type of implanted material and the time of sacrifice. Eight areas of 60.11 mm2 corresponding to the obtained surgical pieces were analyzed, counting mesenchymal cells, eosinophils, and foreign body giant cells, observing an acceptable biocompatibility in all implants, for subsequent statistical analysis by Tukey test. Results: Silicone gel showed inflammation slightly greater than for other groups, with tissue reactions varying from light to moderate, whose result was the formation of a fibrous capsule around the material, recognized by the organism as a foreign body. Conclusion: In general, it is possible to affirm that silicone gel had acceptable levels of biocompatibility, confirmed the rare presence of foreign body giant cells, and when of the rupture, formed a fibrous capsule around the material, separating the material of the organism.

Testing extractants for Cu, Fe, Mn, and Zn in tropical soils treated with sewage sludge for 13 consecutive years

In this paper, we report on a field experiment being carried out in a Typic Eutrorthox. The experiment was initiated in the 1997-98 agricultural season as a randomized block design with four treatments (0, 5, 10, and 20 t ha -1) of sewage sludge and five replicates. Compound soil samples were obtained from 20 subsamples collected at depths of 0-0.1 and 0.1-0.2 m. Cu, Fe, Mn, and Zn concentrations were extracted with DTPA pH 7.3; 0.1 mol L -1 HCl, Mehlich-I, Mehlich-III, and 0.01 mol L-1 CaCl 2. Metal concentrations were determined via atomic absorption spectrometry. Diagnostic leaves and the whole above-ground portion of plants were collected to determine Cu, Fe, Mn, and Zn concentrations extracted by nitric-perchloric digestion and later determined via atomic absorption spectrometry. Sewage sludge application caused increases in the concentrations of soil Cu, Fe, and Mn in samples taken from the 0-0.1 m depth evaluated by the extractants Mehlich-I, Mehlich-III, 0.01 mol L-1 HCl and DTPA pH 7.3. None of the extractants provided efficient estimates of changes in Mn concentrations. The acid extractants extracted more Cu, Fe, Mn, and Zn than the saline and chelating solutions. The highest concentrations of Cu, Fe, and Zn were obtained with Mehlich-III, while the highest concentrations of Mn were obtained with HCl. We did not observe a correlation between the extractants and the concentrations of elements in the diagnostic leaves nor in the tissues of the whole maize plant (Zea mays L.). © 2013 Springer Science+Business Media Dordrecht.

Chitosan-collagen scaffolds can regulate the biological activities of adipose mesenchymal stem cells for tissue engineering

Scaffolds of chitosan and collagen can offer a biological niche for the growth of adipose derived stem cells (ADSC). The objective of this work was to characterize the physico-chemical properties of the scaffolds and the ADSC, as well as their interactions to direct influences of the scaffolds on the behavior of ADSC. The methodology included an enzymatic treatment of fat obtained by liposuction by collagenase, ASDC immunophenotyping, cell growth kinetics, biocompatibility studies of the scaffolds analyzed by the activity of alkaline phosphatase (AP), nitric oxide (NO) determination by the Griess-Saltzman reaction, and images of both optical and scanning electron microscopy of the matrices. The extent of the crosslinking of genipin and glutaraldehyde was evaluated by ninhydrin assays, solubility tests and degradation of the matrices. The results showed that the matrices are biocompatible, exhibit physical and chemical properties needed to house cells in vivo and are strong stimulators of signaling proteins (AP) and other molecules (NO) which are important in tissue healing. Therefore, the matrices provide a biological niche for ADSC adhesion, proliferation and cells activities.