Made available in DSpace on 2014-10-09T12:46:09Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:44Z (GMT). No. of bitstreams: 0 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Foram elaborados e implementados testes de controle de qualidade em equipamentos de angiografia por subtração digital. Estes testes foram baseados em normas nacionais e internacionais e foram implementados em cinco equipamentos de três instituições diferentes. Estes testes avaliam os parâmetros de desempenho dos equipamentos e são utilizados para a determinação da taxa de kerma no ar na entrada da pele do paciente e do corpo clínico. Os testes foram realizados utilizando dispositivos, simuladores de pacientes e câmaras de ionização. Os testes convencionais e do sistema de subtração digital indicaram que os equipamentos avaliados encontravam-se em bom estado de desempenho. Os testes para verificação da taxa de kerma no ar indicaram que um dos equipamentos avaliados apresentou altas taxas de kerma no ar na entrada da pele do paciente em modo fluoroscopia. Este problema foi notificado, e as devidas providências foram imediatamente tomadas pela gerência do hospital. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP / FAPESP:99/06803-9

Made available in DSpace on 2014-10-09T12:49:16Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:43Z (GMT). No. of bitstreams: 1 09999.pdf: 3180052 bytes, checksum: d81b6ae3a2be068f0f996c5912f80e5b (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

Na reconstrução mamária com microcirurgia, a qualidade dos vasos, a proximidade com a região torácica e a anatomia constante são fatores relevantes na escolha do pedículo receptor. Apesar da grande aplicação clínica, os vasos toracodorsais e torácicos internos apresentam restrições como a imprevisibilidade da qualidade nas reconstruções tardias, as alterações do contorno do tórax e a inviabilidade de uma eventual revascularização futura do miocárdio. Com o desenvolvimento dos retalhos vascularizados por vasos perfurantes e o maior treinamento dos cirurgiões, novas alternativas de pedículos foram desenvolvidas. A preservação da cartilagem costal e dos vasos torácicos internos, bem como a maior exposição do campo operatório são mencionados como vantagens do emprego dos vasos perfurantes do músculo peitoral maior como receptor. Apesar da anatomia dos vasos perfurantes ter sido previamente estudada, são imprecisas as informações sobre sua origem e distribuição no tórax. Ademais, são escassos os dados relacionados à sua incidência e utilização nas reconstruções imediatas e tardias. Na presente investigação foram incluídos dois estudos: anatômico e clínico. No estudo anatômico avaliou-se a origem, distribuição e dimensões dos vasos perfurantes em 24 cadáveres frescos (48 regiões torácicas), por técnica de coloração e posterior dissecção. No estudo clínico analisou-se, 69 pacientes (77 reconstruções mamárias), sendo 46 imediatas e 31 tardias. Constatou-se no estudo anatômico 2,7 vasos perfurantes por região torácica, destes, 93% apresentaram pequeno e médio calibre e concentração preferencial no segundo espaço intercostal. Os vasos e o pedículo perfurante revelaram comprimento médio de 2,4 cm (1,0 a 3,2 cm) e 3,6 cm (2,1 a 4,5 cm), respectivamente. No estudo clínico, não foram observadas diferenças entre as pacientes submetidas à reconstrução imediata e tardia, quanto a idade (p=0,599), IMC (p=0,498), lateralidade da mama (p=0,671), hipertensão arterial sistêmica (p=0,732), diabetes (p>0,999) e tabagismo (0,828). Todavia, 61,3% das pacientes submetidas à reconstrução tardia relataram radioterapia previamente à cirurgia (p<0,001). Nas reconstruções imediatas, em 93,5% dos casos os vasos perfurantes estavam presentes e, em 37,2%, foi possível realizar as anastomoses. Entre as causas de insucesso das anastomoses destacaram-se a lesão vascular durante a mastectomia (48,8%) e a desproporção de calibre dos vasos (13,9%). Nas reconstruções tardias, em 12,9% dos casos, os vasos perfurantes estavam presentes e em nenhum caso foi possível realizar as anastomoses. A incompatibilidade de calibre dos vasos e a má qualidade da estrutura vascular foram as razões para não os empregar como pedículo receptor. Não foram observadas diferenças estatísticas quanto à incidência de complicações gerais (p=0,548), perda parcial do retalho (p=0,494), perda total do retalho (p=0,644) e necrose da pele remanescente da mastectomia (p=0,193) nas pacientes submetidas à reconstrução com pedículo receptor perfurante e com os demais pedículos receptores. Os resultados permitiram-nos concluir que a maior concentração de vasos perfurantes no segundo espaço intercostal e a distância entre 0,5 e 3 cm do esterno constituem parâmetros anatômicos importantes no planejamento da técnica. É recomendável que nas reconstruções imediatas se faça o planejamento prévio com o mastologista com intuito de preservar os vasos perfurantes, enquanto que nas reconstruções tardias, a presença de cirurgia prévia e da radioterapia podem se relacionar à menor reprodutibilidade da técnica / In breast reconstruction with microsurgery, the proper selection of the recipient pedicle is a significant factor for success. The compatibility of caliber and the uniform anatomy are the chief relevant factors in the choice of recipient vessels. Regardless of their broad clinical application, the thoracodorsal and internal thoracic vessels demonstrate limitations such as the unpredictable quality of late reconstructions, the changes in thoracic contour and the impairment for future coronary bypass. The progress of microsurgical technique and the development of perforator flaps has led to new recipient pedicle alternatives. Thus, sparing of the costal cartilages and the internal thoracic vessels as well as the wide surgical exposure are the main advantages of using the pectoralis major perforator vessels as recipient pedicles. Although the anatomy of the perforator vessels has been previously studied, the data about their origin and distribution is inexact. In addition, the data concerning their incidence and quality of immediate and late reconstructions are not available. In the present investigation, an anatomical and clinical study were performed. In the anatomical study, the origin, distribution and size of perforator vessels were evaluated in 24 fresh cadavers (48 thoracic regions) by staining technique and posterior dissection. The clinical study analyzed 69 patients (77 reconstructions), 46 immediate and 31 late reconstructions. The anatomic study observed 2.7 perforator vessels per thoracic region, with 93% presenting small and medium caliber and major concentration in the second intercostal space. The vessels and the perforator pedicles demonstrated an average length of 2.4 cm (1.0 to 3.2 cm) and 3.6 cm (2.1 to 4.5 cm) respectively. In the clinical study, no differences were observed between the immediate and late reconstructions regarding age (p=0.599), BMI (p=0.498), breast side (p=0.671), hypertension (p=0.732), diabetes (p>0.999) and smoking (0.828). Nevertheless, 61.3% of patients submitted to late reconstruction had radiotherapy prior to breast reconstruction (p<0.001). The perforator vessels were observed in 93.5% of the immediate reconstructions and vascular anastomosis was performed in 37.2%. Vascular injury during mastectomy (48.8%) and caliber compatibility (13.9%) were observed as the main causes of failure anastomosis. In late reconstructions, the perforator vessels were present in 12.9% and the anastomosis was impossible in all cases due to caliber differences and vascular quality. No statistical differences were observed regarding the incidence of general complications (p=0.548), partial loss (p=0.494), total loss (p=0.644) and mastectomy flap necrosis (p=0.193) in patients submitted to reconstruction with perforator vessels and the other recipient pedicles. The present study enabled us to conclude that the major concentration of perforator vessels in the second intercostal space and the distance between 0.5 and 3 cm from the sternal region represent an important anatomic parameter. In immediate reconstructions, a preoperative planning between the general and plastic surgeon is fundamental to preserve the main perforator vessels during the mastectomy. In late reconstructions the procedure was not demonstrable and some factors may be involved such as previous surgery and radiation therapy

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / According to the Brazilian Ministry of Health, about 8000 cases of scorpion envenomation are reported yearly in Brazil. Most cases are due to the sting of Tityus serrulatus, known popularly as yellow scorpion. It belongs to the Arachnidea, class, Scorpionidae order, Buthidae family, Tityinae subfamily and Tityus genus. It is present in the Brazilian States of Minas Gerais, EspÃrito Santo, Bahia, Rio de Janeiro, SÃo Paulo, ParanÃ, GoiÃs, Mato Grosso do Sul and Ceara and it is the most dangerous scorpion in Brazil, causing severe envenoming and even death. The effects of T. serrulatus venom (TsV) on the renal physiology in humans consist of increased renal parameters such as urea and creatinine. So far, effects had not been tested in the perfused rat kidney. Isolated kidneys from Wistar rats, weighing 250 to 300g, were perfused with Krebs-Henseleit solution containing 6g% of previously dialysed bovine albumin. The effects of T. serrulatus venom in the 1, 3 and 10 &#956;g/mL concentrations, were studied on the perfusion pressure (PP), renal vascular resistance (RVR), urinary flow (UF), glomerular filtration rate (GFR), sodium tubular transport (%TNa+), potassium tubular transport (%TK+) and chloride tubular transport (%TCl-). Tityus serrulatus venom was added to the system after 30 minutes of internal control; it increased PP (PP30â = 112.4  2.0 vs PP60â = 145.8  17.4mmHg*,*p<0.05) and RVR (RVR30â = 5.88  0.33 vs RVR60â = 7.52  0.86mmHg/mL.g-1.min-1*,*p<0.05), decreased GFR (GFR30â = 0.671  0.076 vs GFR120â = 0.467  0.062mL.g-1.min-1*,*p<0.05) and UF (UF30â = 0.147  0.011 vs UF90â = 0.119  0.013mL.g-1.min-1*,*p<0.05). The mesenteric bed was perfused with Krebs solution kept warm at 37ÂC by a constant flow (4mL/min), while the variable perfusion pressure was measured by means of a pressure transducer. The vascular effects of T. serrulatus venom were examined and compared to the infusion of the perfuse solution. The infusion of T. serrulatus venom (10&#956;g/mL/min) increased the basal perfusion pressure of isolated arteriolar mesenteric bed (basal pressure = 74.17  3.42 vs TsV = 151.8  17.82 mmHg*,*p<0.05). The histopathological evaluation revealed deposits of protein in the renal tubules and urinary spaces of kidneys perfused with TsV. This may reveal that there has been a perfusate extravasation to the parenchyma probably due to increase of hydrostatic pressure induced by TsV. T. serrulatus venom affects renal hemodynamics increasing resistance and perfusion pressure, determining extravasation of perfusate and decreasing the glomerular filtration rate and renal flow. / No Brasil, sÃo notificados, anualmente, cerca de 8.000 acidentes escorpiÃnicos. A espÃcie Tityus serrulatus, popularmente conhecido como escorpiÃo amarelo, pertence à classe Arachnidea, ordem Scorpionidae, familia Buthidae, subfamÃlia Tityinae, gÃnero Tityus. à encontrado nos estados de Minas Gerais, EspÃrito Santo, Bahia, Rio de Janeiro, SÃo Paulo, ParanÃ, GoiÃs, Mato Grosso do Sul e CearÃ, sendo responsÃvel pelos acidentes com maior gravidade e letalidade. Os efeitos do veneno de T. serrulatus (VTs), sobre a fisiologia renal humana, mostraram aumentar os parÃmetros renais, urÃia e creatinina. Entretanto, na perfusÃo de rins de ratos, os efeitos nÃo haviam sido testados atà agora. O objetivo desse trabalho foi estudar os efeitos renais e a reatividade vascular induzidos pelo veneno do escorpiÃo Tityus serrulatus. Foram utilizados ratos Wistar machos pesando entre 250 e 300g, cujos rins foram isolados e perfundidos com SoluÃÃo de Krebs-Hanseleit contendo 6g% de albumina bovina previamente dialisada. Os efeitos de veneno de T. serrulatus, nas concentraÃÃes de 1, 3 e 10 &#956;g/mL (n=6), foram estudados sobre a PressÃo de PerfusÃo (PP), ResistÃncia Vascular Renal (RVR), Fluxo UrinÃrio (FU), Ritmo de FiltraÃÃo Glomerular (RFG), Percentual de Transporte Tubular de SÃdio (%TNa+), de PotÃssio (%TK+) e de Cloreto (%TCl-). O veneno de T. serrulatus foi adicionado apÃs 30 minutos de controle interno e aumentou a PP (PP30â = 112,4  2,0 vs PP60â = 145,8  17,4mmHg*,*p<0,05), a RVR (RVR30â = 5,88  0,33 vs RVR60â = 7,52  0,86mmHg/mL.g-1.min-1*,*p<0,05) e diminuiu o RFG (RFG30â = 0,671  0,076 vs RFG120â = 0,467  0,062mL.g-1.min-1*,*p<0,05) e o FU (FU30â = 0,147  0,011 vs FU90â = 0,119  0,013mL.g-1.min-1*,*p<0,05). O leito mesentÃrico foi perfundido, com soluÃÃo de Krebs, sob a temperatura de 37ÂC, a um fluxo constante (4mL/min), enquanto a pressÃo de perfusÃo era mensurada atravÃs de um transdutor de pressÃo. Os efeitos vasculares do veneno de T. serrulatus 10&#956;g/mL/min; n = 6) foram examinados e comparados com a infusÃo apenas da soluÃÃo perfusora. A infusÃo do veneno de T. serrulatus aumentou a pressÃo basal de perfusÃo do leito mesentÃrico isolado (pressÃo basal: 74,17  3,42 vs VTs 151,8  17,82mmHg*, *p<0,05). A avaliaÃÃo histolÃgica revelou depÃsitos de proteÃnas nos tÃbulos renais e nos espaÃos urinÃrios dos rins perfundidos com o veneno de T. serrulatus. Isso pode revelar que houve um extravasamento do perfusato para o parÃnquima, devido, provavelmente, ao aumento da pressÃo hidrostÃtica promovida por VTs. O veneno de T. serrulatus, entÃo, promove efeitos hemodinÃmicos renais que elevam a resistÃncia e a pressÃo de perfusÃo, forÃando a passagem de proteÃnas para os tÃbulos e diminuindo o ritmo de filtraÃÃo glomerular e o fluxo urinÃrio.

No description available.

Intermittent blood flow in tumour microvasculature is believed to contribute to heterogeneity in tumour oxygen delivery; transient vessel nonperfusion is thought to result in acutely hypoxic cells resistant to conventional radiotherapy. This thesis describes three main areas of work: (1) the development of a histologic method capable of detecting intermittent blood flow in experimental tumours at the single vessel level; (2) the quantification and characterization of tumour blood flow fluctuations in the murine SCCVII carcinoma; and (3) the modification of tumour blood flow and the reduction of flow heterogeneity using vasoactive drugs. A double staining technique involving the sequential intravenous injection of two fluorescent vascular markers was used to detect transient episodes of tumour vessel nonperfusion. The stains employed were Hoechst 33342 and the carbocyanine dye, DiOC₇(3), both of which have short (< 3 minutes) circulation half-lives and preferentially stain cells adjacent to perfused blood vessels. When injections of the vascular markers are separated by some interval, each stain defines only those tumour vessels which were perfused during the few minutes immediately post-injection; thus, two "pictures" of tumour microvascular flow are obtained and tumour vessels subject to periods of nonperfusion can be easily visualized in frozen sections since they are outlined by one stain but not the other. Using the double staining technique, in which Hoechst 33342 and then DiOC₇(3) are administered intravenously 20 minutes apart to unrestrained C3H/He mice, staining mismatch (indicative of transient vessel nonperfusion) is regularly observed in subcutaneous SCCVII carcinoma. Vessels stained with DiOC₇(3) only (reperfusion of previously nonperfused vessels) or with H33342 only (nonperfusion of previously perfused vessels) are observed in approximately equal numbers. The percentage of tumour vessels subject to intermittent flow is a function of SCCVII tumour size: tumours ≤100 mg do not exhibit statistically significant amounts of mismatch. At sizes > 100 mg, overall staining mismatch is significantly increased over background levels and maximum mismatch is observed at tumour sizes >400 mg (8.6 ±2.9%). In most tumours, transient vessel nonperfusion is more pronounced in central tumour regions. In addition to mismatch observed in individual vessels, large "patches" of unequal staining are also seen. Anaesthesia or restraint do not significantly influence intermittent blood flow. The above information suggests that transient episodes of tumour vessel nonperfusion occur as a consequence of flow reduction in a feeding vessel; vessels in central regions of large tumours may be susceptible to collapse as a result of elevated tumour interstitial pressure. In the SCCVII tumour, a small number of peripheral vessels possess vascular smooth muscle and thus may be capable of vasomotor activity. The importance of perfusion pressure in the control of tumour microcirculatory flow was examined using vasoactive drugs. Hydralazine, a vasodilator which lowers blood pressure, causes a profound reduction in tumour RBC flow to 8.7 + 6.4% of pretreatment values in unanaesthetized mice. The drug causes collapse of central tumour vessels: following a dose of 10mg/kg intravenously, 36±16% of vessels are completely nonperfused, as detected using the double staining technique. Conversely, elevation of blood pressure using the vasoconstrictor angiotensin II results in a 2-3x increase in tumour blood flow. In addition, angiotensin II infusion significantly reduces the number of tumour vessels subject to transient nonperfusion from 8.1 % to 2.0%. However, intermittent blood flow in the SCCVII carcinoma can also be influenced by nonvasoactive drugs: nicotinamide, the amide form of vitamin B3, reduces episodes of transient nonperfusion. In summary, intermittent blood flow has been characterized in a transplanted murine squamous cell carcinoma using a novel fluorescent double staining method which allows the detection of flow fluctuations in solid tumours at the microvascular level. If transient episodes of nonperfusion occur in human tumours and result in impaired oxygen or drug delivery, then such flow fluctuations may be an important factor limiting tumour cure or local control by radiotherapy or chemotherapy. / Medicine, Faculty of / Pathology and Laboratory Medicine, Department of / Graduate

This master's thesis deals with the classification of the retinal blood vessels in retinal image data. The thesis contains a description of anatomy of the human eye with focus on the blood circulation, and imaging and diagnostic methods of the retina are briefly mentioned further. The thesis also summarizes methods of the blood circulation classification with emphasis on the deep learning. The practical section was implemented in Python programming language and describes the pre-processing of the data with determination of AV ratio. Based on a literature search, the U-net architecture was chosen for the classification of the retinal blood vessels. The architecture was modified using the open-source Keras library and tested on images from the experimental video-ophthalmoscope. The modified architecture was initially used for classification of vessels into the corresponding classes and because of unsatisfying results was modified another architecture segmenting retinal vessels, arteries or veins and a proposition of a method of the blood vessels classification.

This thesis deals with processing of retinal fundus images. Vision is the most important human sense and its injury has very serious consequences for humans. Automatic processing of retinal images increases the efficiency of medical examination and accelerates diagnoses of deseases. Retina exhibits unique characteristics for each person and thus can also be used to identify people. In this task is briefly discussed the structure and properties of each parts of the eye, particularly the retina, and their possible diseases such as diabetic retinopathy, glaucoma and age related macular degeneration. Subsequently, the task describes the representation and characteristics of the digital image. Also is devoted to selected image segmentation methods namely thresholding, edge detection and segmentation techniques based on the matched filter. The outcome of this task is the application in which several segmentation methods are implemented for the blood vessels extraction. For each of these methods it is possible to set the parameters of the segmentation to ensure high quality blood vessels extraction in images of different quality.

The content of this work is the analysis of retinal vessels pulsation of video sequences acquired by experimental fundus camera based on measuring the brightness profile of the vessel. The first level of analysis in this work is the segmentation of blood vessels and diameter measurement of blood vessels during the sequence. The work contains research methods dealing with the diameter measurement and evaluation of pulsation and analysis segmentation methods using for analysing the vasculature of the retina. From these methods, a vessel tracking method was selected. In segmented video sequences is on the ground of intensity profiles analysed vessel pulsation. Analysis is also made on original dataset and results are discussed considering the frequency characteristic.

<p>   </p> <p>Environmental toxicants such arsenic (As) and lead (Pb) are chemicals that enter the environment and can result in adverse health effects humans, especially during development. This dissertation work evaluated As and Pb to determine if developmental toxicity significantly changes at lethal and sub-lethal mixture concentrations using the zebrafish model. Joint action models were applied to survival data to determine the type of interaction. Metal exposures were from 1-120 hours post fertilization (hpf). As concentrations were 0-7,500 ppb. Pb concentrations were 0–100,000 ppb. The LC25, LC50, and LC75 values at 120 hpf from single metal exposures were used to select mixture concentrations for modeling. The survival data indicated an additive effect occurred at lethal concentrations. </p> <p>The impact of the mixture on behavior, morphology, and gene expression was then evaluated at sub-lethal concentrations of 10 and 100 ppb As and Pb individually or in mixtures. Data was analyzed with a repeated measures ANOVA (behavior) or an ANOVA (morphology and qPCR) with the least significant difference test (α=0.05). Zebrafish larvae exposed to 10 ppb As exhibited hyperactivity in all dark phases for the distance moved, time moving, and velocity, while those exposed to 10 ppb Pb only showed an increase in distance moved and velocity in the first dark phase. The 10 ppb mixture was found to have an intermediate impact with increased time moving in all dark phases and increased distance moved and velocity only in the first dark phase. In contrast, hyperactivity was observed only in the 100 ppb As and 100 ppb mixture treatment in the last two dark phases for time spent moving. No significant behavioral alterations occurred in the 100 ppb Pb treatment. A decrease in mean brain length and brain length ratio to the total length in the 10 ppb mixture was observed with no significant morphology changes observed for head length, head width, or total length. Alternatively, measurements of cerebral vasculature morphology in the mesencephalon (midbrain) and cerebellum (hindbrain) uncovered decreased total vascularization at 72 hpf (exposure 1-72 hpf) in both brain regions. This decrease occurred in all treatment groups in the mesencephalon and in all treatment groups, except the 100 ppb Pb and 10 ppb As treatment groups in the cerebellum. In addition, decreased sprouting and branching occurred in the mesencephalon, while only decreased branching was measured in the cerebellum. The 10 ppb Pb treatment group showed unique perturbations in several cerebral vasculature endpoints evaluated, which was also observed in a specific gene expression alteration pattern different from the other treatment groups. To identify molecular changes associated with these changes, expression of genes related to angiogenesis and vasculogenesis (i.e., <em>vegfaa, wnt7aa,</em> and<em> lrp1aa</em>) and genes associated with tight junctions (i.e., <em>cldn5a</em> and <em>cldn5b</em>) were assessed at 72 hpf. Increased <em>cldn5b</em> expression was detected in all treatment groups, while <em>cldn5a </em>was increased in only the 10 ppb Pb treatment group. In addition, <em>wnt7aa</em> was only decreased in the 10 ppb Pb treatment group. Alternatively, <em>vegfaa</em> was increased in the 100 ppb As and 100 ppb mixture treatment groups and no changes were detected for <em>lrp1aa</em>. In summary, cerebral vascular toxicity outcomes in the 10 ppb mixture treatment were primarily driven by changes in the 10 ppb Pb treatment group, while perturbations in the 100 ppb mixture treatment group aligned with the 100 ppb As alterations. In addition, the non-linear dose response for 10 and 100 ppb Pb treatment groups agree with observations in prior studies. qPCR results indicate that both metals together and separately alter cerebral vasculature development at environmental regulatory levels. </p> <p>Lastly, with the increase in the prevalence of neurodegenerative diseases increasing globally, there is a need to evaluate more therapeutics at a high through-put pace and to pinpoint the cause of the sporadic cases. CRISPR-Cas9 technology offers a relatively inexpensive, reliable, and precise advantages over its predecessors when it comes to producing mutant disease models of neurodegeneration. A method to create the expression vector needed for creation of a CRISPR Cas9 knock-in model is detailed in this dissertation. The methodology to insert a chimeric DNA sequence contain human DNA has been created, and the <em>in silico</em> assays used to produce the reactant for this methodology were successful. It has been determined that the efficiency of this knock-in method is limited to the success of producing the chimeric model which is limited itself by the number of molecules included into the chimeric sequence. Overall, the results show that the overlap primers designed in silico need to be re-designed to improve efficiency of the initial reactions required to produce the first plasmid containing the required machinery for a successful knock in of exogenous human DNA.</p>