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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

A gross anatomical and histological study of the oropharynx and proximal oesophagus of the emu (Dromaius novaehollandiae)

Crole, Martina Rachel 13 May 2009 (has links)
This study describes the gross anatomical, histological and surface morphological features of the oropharynx and proximal oesophagus of the emu in order to address the scarcity of information on this region in this commercially important bird. Heads obtained from birds at slaughter (and a younger and older bird from emergency farm slaughter) were used for this study and described using basic gross anatomical and histological techniques, supplemented by scanning electron microscopy. The findings of the study were compared with the relevant literature. The oral and pharyngeal cavities could not be morphologically separated and formed a single cavity. This cavity was dorso-ventrally flattened and clearly divided, both on the floor and the roof, into rostral pigmented and caudal non-pigmented parts. The non-pigmented floor housed the tongue and laryngeal mound which had a wide glottis and no papillae. The choana was triangular-shaped, with a small caudo-lateral fold on either side, and was situated in the nonpigmented part of the roof. Caudal to the choana were two rounded pharyngeal folds with a pitted ventral surface. A small bilateral projection from the caudo-lateral edge consisted mainly of diffuse lymphoid tissue. The pharyngeal folds contained numerous large simple branched tubular mucus-secreting glands as well as large accumulations of lymphoid tissue. The pigmented regions of the roof and floor were aglandular and lined by a keratinised stratified squamous epithelium which, particularly in the roof, contained numerous Herbst corpuscles in the underlying connective tissue. SEM revealed the surface to be composed of sheets of desquamating flattened polygonal cells. The non-pigmented regions were glandular and lined by a non-keratinised stratified squamous epithelium. Surface cells displayed a pattern of microplicae or microvilli while individual surface cells were seen to desquamate. The connective tissue housed small, simple tubular and large, simple branched tubular mucus-secreting glands, Herbst corpuscles (only absent from the pharyngeal folds and proximal oesophagus), lymphoid tissue, blood vessels and nerves. The glands of the upper digestive tract were polystomatic and named as follows according to their location: Caudal intermandibular, lingual, crico-arytenoid, oral angular, caudal palatine, pharyngeal and oesophageal. The openings of the glands to the surface were seen on SEM as variably sized holes on the surface, some being obscured by mucus secretions from the underlying glands. Taste receptors were sparse and present only in the caudal non-pigmented oropharyngeal floor, tongue root and proximal oesophagus. Accumulations of lymphoid tissue were identified at the junction between the two regions of the roof, and in the non-pigmented roof, the non-pigmented floor, tongue ventrum, root and frenulum, proximal oesophagus and pharyngeal folds. The consistent dense accumulation of lymphoid tissue in the pharyngeal folds constituted pharyngeal tonsils (Lymphonoduli pharyngeales). The lymphoid tissue of the non-pigmented floor was visible macroscopically as round raised nodules. Specific, unnamed larger lymphoid tissue aggregations were located at the junction of the tongue ventrum and frenulum and in the small folds lateral to the choana. Surface morphology, as seen by SEM, revealed a pattern of microridges on the surface cells of the keratinised areas, whereas the surface cells of the non-keratinised areas displayed microplicae, microvilli and cilia. Microvilli and cilia were associated with the gland openings and ducts. The proximal oesophagus was a cylindrical tube with a longitudinally folded mucosa and displayed the typical tissue layers described in birds. The mucosa was formed by a nonkeratinised stratified epithelium which on SEM showed minimal surface desquamation. The lamina propria contained numerous simple tubular mucus-secreting glands which sometimes branched and occasional diffuse lymphoid tissue aggregations. The gland openings to the surface were seen on SEM as small and large dark holes. The muscularis mucosae was very prominent and was a longitudinal smooth muscle layer separating the mucosa from the submucosa. The tunica muscularis was composed of a thicker inner circular and a thinner outer longitudinal smooth muscle layer surrounded by the outer loose connective tissue forming the tunica adventitia. The emu tongue was divided into a body and a root. The body was triangular, dorso-ventrally flattened, pigmented and displayed caudally directed lingual papillae on both the lateral and caudal margins. The root, a more conspicuous structure in comparison to other ratites, was triangular, with a raised bulbous component folding over the rostral part of the laryngeal fissure. The lingual skeleton was formed by the triangular-shaped paraglossum (hyaline cartilage), forming the core of the tongue body, and the rostral projection of the basihyale, ventral to the paraglossum. Following the general trend in ratites, the emu tongue was greatly reduced in comparison to the bill length and specifically adapted for swallowing during the cranioinertial method of feeding employed by palaeognaths. The tongue was invested by a non-keratinised stratified squamous epithelium. The glands in the connective tissue formed the bulk of the parenchyma and were composed of both small simple tubular and large simple branched tubular mucus-secreting glands similar to those seen in the oropharynx. The lingual glands were grouped as follows: dorsal and rostro-ventral (large glands), caudo-ventral and radical (large and small glands) and frenular (small glands). The large glands were visible macroscopically as doughnut-shaped structures. Melanocytes were absent from the tongue ventrum and occasionally from the tongue root. Lymphoid tissue was absent from the tongue dorsum. Herbst corpuscles were present in the tongue body and root and generally closely associated with the large mucus-secreting glands. The surface morphology varied in the different regions of the tongue. The dorsal and rostro-ventral tongue body showed individual desquamating cells and large gland openings only, the caudo-lateral ventrum showed less desquamation and both large and small openings. The mid-ventral aspect had an undulating uneven appearance with round raised cells on the surface which were densely packed with microvilli. Very large, large and small openings were present in this region and ciliated cells occurred in the vicinity of gland openings. This study presented various unique findings regarding the morphology of the emu oropharynx compared to other ratites. Although the sense of taste has been confirmed in many avian species, this study presented the first evidence of taste in the emu and ratites in general and suggests the possibility of taste being previously overlooked in the other birds studied (ostrich and greater rhea). The tongue root of the emu was clearly defined and is unique in structure and possible function amongst the ratites and other birds. Previously unmentioned functions of the emu tongue revealed by this study include: touch (Herbst corpuscles), taste (taste bud), lubrication and mechanical protection (mucus-secreting glands), immunological (lymphoid tissue) and digestive (swallowing). It was also noted that the various structures and organs of the oropharynx revealed important and often interesting differences between the emu and the other ratites documented. The prominent serrations of the rostral mandibular tomia of the emu also appear to be unique amongst ratites. The presence and wide distribution of Herbst corpuscles within the emu oropharynx and tongue show these areas to be highly sensitive to touch. The caudo-lateral projections of the pharyngeal folds effectively formed pharyngeal tonsils, a feature not apparent in other ratites. Despite the differences noted between the emu and other ratites it was possible to discern a common pattern of structures and features, with their modifications, both within and forming the oropharynx in this group of birds. / Dissertation (MSc)--University of Pretoria, 2009. / Anatomy and Physiology / unrestricted
12

Discohesive growth pattern (Disco-p) as an unfavorable prognostic factor in lung adenocarcinoma: an analysis of 1062 Japanese patients with resected lung adenocarcinoma / 肺腺癌の予後不良因子としての非結合性増殖パターン(Disco-p):肺腺癌を切除した日本人患者1062人の解析

Kurata, Mariyo 26 September 2022 (has links)
京都大学 / 新制・課程博士 / 博士(医学) / 甲第24186号 / 医博第4880号 / 新制||医||1060(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 中山 健夫, 教授 平井 豊博, 教授 中本 裕士 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
13

Applying Skeletal, Histological and Molecular Techniques to Syphilitic Skeletal Remains from the Past / Applying Skeletal, Histological and Molecular Techniques

von Hunnius, Tanya 08 1900 (has links)
Many have been searching for and contemplating the origins of syphilis. By understanding its emergence as a human pathogen we will be better able to elucidate its evolution through time and space as well as shed light on its current state. Ancient DNA techniques used to isolate Treponema pallidum subspecies pallidum DNA from archaeological human specimens provides direct evidence of its existence in the past. To date, only Kolman et al. (1999) have been successful in this endeavour. Along with this protocol, two other published protocols and novel allele specific techniques this thesis aims to add new cases of venereal syphilis identification from historic human remains. To accomplish this, sixteen skeletal samples from different time periods and geographic locations were collected for this project. Of importance are those dating from the Civil War time period from the United States as medical documents state these individuals suffered and/or died from the complications of syphilis. Samples from the United Kingdom are also critical to this analysis as they have confirmed pre-Columbian dates. Along with attempts to isolate bacterial DNA, endogenous DNA (mitochondrial and amelogenin) is analyzed to provide an idea of the different levels of molecular preservation. General preservation as well as the identification of syphilis are also performed using microscopic techniques. By using a tiered approach (macroscopic to microscopic to molecular), a better idea of both preservation and disease presence can be ascertained. Results indicate that although syphilis could be identified at both the macroscopic and microscopic levels for some individuals and endogenous DNA was present, treponemal DNA failed to amplify. Many different reasons are suggested, for example poor conservation methods, misdiagnosis and diagenesis, but the most important possibility is the lack of bacterial DNA in bone at later stages of syphilis which was confirmed using the rabbit model. As a result, the present techniques may not be conducive for treponemal DNA isolation from ancient human remains. / Thesis / Doctor of Philosophy (PhD)
14

Automated Tissue Image Analysis Using Pattern Recognition

Azar, Jimmy January 2014 (has links)
Automated tissue image analysis aims to develop algorithms for a variety of histological applications. This has important implications in the diagnostic grading of cancer such as in breast and prostate tissue, as well as in the quantification of prognostic and predictive biomarkers that may help assess the risk of recurrence and the responsiveness of tumors to endocrine therapy. In this thesis, we use pattern recognition and image analysis techniques to solve several problems relating to histopathology and immunohistochemistry applications. In particular, we present a new method for the detection and localization of tissue microarray cores in an automated manner and compare it against conventional approaches. We also present an unsupervised method for color decomposition based on modeling the image formation process while taking into account acquisition noise. The method is unsupervised and is able to overcome the limitation of specifying absorption spectra for the stains that require separation. This is done by estimating reference colors through fitting a Gaussian mixture model trained using expectation-maximization. Another important factor in histopathology is the choice of stain, though it often goes unnoticed. Stain color combinations determine the extent of overlap between chromaticity clusters in color space, and this intrinsic overlap sets a main limitation on the performance of classification methods, regardless of their nature or complexity. In this thesis, we present a framework for optimizing the selection of histological stains in a manner that is aligned with the final objective of automation, rather than visual analysis. Immunohistochemistry can facilitate the quantification of biomarkers such as estrogen, progesterone, and the human epidermal growth factor 2 receptors, in addition to Ki-67 proteins that are associated with cell growth and proliferation. As an application, we propose a method for the identification of paired antibodies based on correlating probability maps of immunostaining patterns across adjacent tissue sections. Finally, we present a new feature descriptor for characterizing glandular structure and tissue architecture, which form an important component of Gleason and tubule-based Elston grading. The method is based on defining shape-preserving, neighborhood annuli around lumen regions and gathering quantitative and spatial data concerning the various tissue-types.
15

Avaliação dos parâmetros funcionais e histológicos associados à exposição do peixe beijupirá Rachycentron canadum (Linnaeus, 1766) a concentrações subletais de hidrocarbonetos policíclicos aromáticos (HPAs). / Evaluation of functional and histological parameters associated to beijupirá Rachycentrun canadum (Linnaeus, 1766) exposure to sublethal concentrations of policyclic aromatic hidrocarbons (PAHs).

Silva Neto, Gabriel Marcelino da 29 May 2015 (has links)
O petróleo é um dos xenobióticos mais utilizados pela humanidade e também um dos mais prejudiciais aos seres vivos. A formação do petróleo é composta em 97% por hidrocarbonetos, que são os maiores poluentes em potencial. Os hidrocarbonetos policíclicos aromáticos (HPAs), os maiores constituintes do petróleo, são poluentes orgânicos de grande persistência ambiental, e seus compostos derivados são potenciais carcinogênicos que podem afetar toda biota em que estejam envolvidos. O presente estudo teve como objetivo avaliar os efeitos da exposição subletal aos HPAs na concentração de 0,4 ppm em peixes marinhos da espécie Rachycentron canadum por meio de parâmetros morfométricos, metabólicos e histológicos. Os HPAs foram obtidos através da extração da fração solúvel de petróleo em água (FSA) e avaliados qualitativamente por meio de espectrometria de fluorescência. Foram avaliados os índices hepato-somáticos (IHS), assim como as possíveis alterações histológicas do tecido hepático dos peixes, supostamente decorrentes da exposição ao xenobiótico. Os parâmetros metabólicos através de biomarcadores de estresse como o cortisol, a glicose e o lactato plasmáticos, assim como a análise complementar por meio das proteínas totais foram determinados. Os resultados obtidos neste trabalho demonstram que os espécimes de Rachycentron canadum não sofreram alterações nos parâmetros estressores quando submetidos à exposição aos HPAs. Quanto à análise histológica, os animais experimentais apresentaram alterações moderadas a graves no fígado decorrente da exposição aos HPAs. Os beijupirás demonstraram ser bons bioindicadores, por suas características comportamentais e respostas aos parâmetros analisados, o que pode viabilizá-lo como objeto de pesquisa. Cada vez mais, estudos que avaliam o impacto de xenobióticos como os HPAs, os quais em concentrações mínimas em organismos aquáticos podem afetar todo o equilíbrio da biota, evidenciam a importância do monitoramento ambiental, uma vez que a dispersão dos xenobióticos no ambiente pode resultar em mudanças em longo prazo. / Oil is one of the humanity most used xenobiotics, and also one of the more dangerous to animals. Oil has about 97% of hydrocarbons in its constitution, which have the major pollutant potential. Polycyclic Aromatic Hidrocarbons (PAHs) are organic pollutants of high environmental persistence level, and its derivatives have carcinogenic potential and can affect all involved biota. The present study aimed to evaluate the sub lethal exposure effects do PAH in the marine fish Rachycentron canadum by morphometric, metabolic and histological parameters. PAHs were obtained by extraction of oil soluble fraction in water (WSA) and were quantitatively evaluated by fluorescence spectrometry. Bioassays were performed using the concentration of 0.4 ppm previously determined. We evaluated the hepatosomatic index (HSI) and the possible histological changes in the liver of the fish, supposedly obtained in consequence of the exposure to the xenobiotic. Metabolic parameters using biomarkers of stress such as cortisol, plasma glucose and lactate, as well as additional analysis by total protein, were determined. Our results showed that Rachycentron canadum did not show alterations on the parameters of stress. Regarding to the histological analysis, animals presented mild to severe changes in the liver, possibly as result of PAHs exposure. Rachycentron canadum resulted to be a good bioindicator, because of its behavioral characteristics and responses to analyzed parameters, which can make it viable as subject for researches. Studies that evaluate xenobiotic impacts like PAHs, in which minimal concentrations can affect the equilibrium of all biota, show the importance of environmental monitoring, once environmental xenobiotics dispersion can produce long term changes.
16

Avaliação histológica e microtomográfica do efeito de células osteoblásticas originárias da medula óssea em defeitos ósseos na calvária de ratos submetidos a um modelo experimental de osteorradionecrose / Histological and microtomographic evaluation of the effect of osteoblastic cells originating from the bone marrow on bone defects in the calvaria of rats submitted to an experimental model of osteorxadionerosis

Sório, Ana Luisa Riul 30 June 2017 (has links)
A osteorradionecrose é uma séria e debilitante consequência da radioterapia da cabeça e pescoço, definida como uma área óssea que não sofre reparação após a irradiação. O objetivo deste trabalho foi analisar o efeito in vivo da presença de células mesenquimais da medula óssea carreadas em gel em defeitos provocados na calvária de ratos submetidos a um modelo experimental de osteorradionecrose. Foi realizada a obtenção de células osteoblásticas da medula óssea de ratos cultivadas in vitro e devidamente caracterizadas quanto ao seu fenótipo por meio de ensaios bioquímicos como proliferação celular, atividade de fosfatase alcalina e sua detecção in situ, além da detecção e quantificação de nódulos mineralizados. Posteriormente, ratos wistar foram submetidos ao protocolo de osteorradionecrose (irradiação com 20 Gy em dose única) e pareados com controles para em seguida serem realizados defeitos nas calvárias para inserção de células osteoblásticas da medula óssea previamente cultivadas in vitro juntamente com gel carreador e realizada a sutura. Os animais foram divididos em 4 grupos: controle (C), controle + células osteoblásticas (CC); osteorradionecrose (IR) osteorradionecrose + células osteoblásticas (IRc). Ao final de 4 semanas os animais foram sacrificados e realizados os seguintes ensaios: (1) análise histológica com base em cortes histológicos descalcificados (2) análise tomográfica por meio de micro-CT dos defeitos previamente criados. Os dados obtidos foram submetidos ao teste de normalidade e posteriormente à análise estatística para p<0,05. As células mesenquimais derivadas da medula óssea apresentaram fenótipo característico de células osteoblásticas após serem cultivadas em meio osteogênico, com aumento da proliferação, atividade de fosfatase alcalina e formação de nódulos mineralizados quando comparado com as células cultivadas em meio basal. A análise qualitativa dos cortes histológicos corados em hematoxilina-eosina e tricrômico de Masson demonstrou maior neoformação óssea no grupo IRc quando comparado ao grupo IR e similar ao grupos controles. A análise tomográfica revelou um aumento na espessura trabecular, densidade de conectividade, número trabecular e superfície óssea no grupo IRc em relação ao grupo IR. Os resultados sugerem que a inserção de células mesenquimais diferenciadas em osteoblastos favorece a neoformação de defeitos ósseos na presença de osteorradionecrose. / Osteoradionecrosis is a serious and debilitating consequence of head and neck radiotherapy, defined as a bone area that does not repair after irradiation. The purpose of this investigation was to analyze in vivo the presence of mesenchymal cells from bone marrow in calvariae defects of rats submitted to osteoradionecrosis. Cells were collected from rat femur bone marrow to perform characterization of osteoblastic phenotype by means of biochemical assays such as cell proliferation, alkaline phosphatase activity and its in situ detection and mineralization. Afterwards, male wistar rats were submitted to osteoradionecrosis protocol (20 Gy in a single dose) and paired with control animals. After 30 days, there were performed calvariae defects and placement of osteoblastic cells previously cultured with a gel vehicle inside the defects, which were sutured properly. The animals were divided in 4 groups: control (C), control + osteoblastic cells (CC), osteoradionecrosis (IR) osteoradionecrosis + osteoblastic cells (Irc). After 30 days, the animals were euthanized to perform the following analysis: (1) Histological evaluation by means of decalcified slide sections stained with hematoxilin-eosin and Masson trichrome; (2) Tomographic evaluation by means of adequate parameters. Data obtained were submitted to normality test and statistical analysis for p<0,05. The mesenchymal cells from bone marrow presented osteoblastic phenotype after being cultured in osteogenic medium, with higher ALP detection and activity, as well as an increase of mineralized nodules when compared to cells cultured in basal medium. Histological analysis showed that irradiation impaired bone neoformation and affected bone marrow composition, as well as the presence of osteoblasts and osteocytes. On the other hand, cell therapy in group IRc improved bone neoformation when compared to group IR, showing similarity to control groups. Tomographic analysis revealed an increase in trabecular thickness, density of connectivity, trabecular number and bone surface when compared to group IR. The results suggest that the placement of mesenchymal cells differentiated in osteoblasts may improve bone neoformation of defects created after the onset of osteoradionecrosis.
17

Estudo da reparação óssea por espectroscopia ATR-FTIR após remoção de fragmento da região mandibular com laser de Er,Cr:YSGG ou broca multilaminada / Study of bone repair by ATR - FTIR spectroscopy technique after the removal of a fragment from jaw region using Er,Cr:YSGG laser or drill

Benetti, Carolina 06 August 2014 (has links)
A reparação óssea é um fator crítico para o sucesso de procedimentos odontológicos e ortopédicos que necessitem do corte ósseo, sendo desejado que esta ocorra de forma rápida e eficaz. Uma maior compreensão da reparação óssea em um nível estrutural e molecular é o primeiro passo para o desenvolvimento de técnicas de corte e terapias regenerativas. Neste contexto, a técnica de FTIR possibilita obter informações sobre a estrutura e composição de tecido mineralizado. O principal objetivo deste projeto foi verificar a eficácia da espectroscopia FTIR na caracterização de diferentes estágios da reparação óssea após a realização de remoção óssea utilizando duas ferramentas de corte: o laser de Er,Cr:YSGG ou uma broca carbide multilaminada, em alta rotação. Foi realizada a remoção de dois fragmentos ósseos da mandíbula de 30 coelhos, e o processo de reparação óssea foi estudado imediatamente, 3, 7, 15, 21, e 28 dias após o procedimento cirúrgico. Utilizou-se a técnica de espectroscopia FTIR para a aquisição das imagens espectrais dos diferentes estágios de reparação, e foi analisada a proporção entre os compostos do tecido utilizando as bandas de amidas, colágeno, carbonato e fosfato dos espectros de absorção. Também foi realizada a análise histológica dos mesmos estágios de reparação estudados. A técnica de espectroscopia FTIR se mostrou eficaz na caracterização do processo de reparação óssea. Observou-se uma tendência de aumento na proporção de compostos orgânicos até o Grupo 15D, após o qual houve aumento na proporção de compostos inorgânicos indicando maior mineralização após este período. Os resultados da análise histológica mostraram diferenças nos primeiros estágios de reparação entre o corte ósseo com o laser de Er,Cr:YSGG e a broca em alta rotação. Essas diferenças não foram detectadas na espectroscopia FTIR com as técnicas de análise utilizadas. Ainda assim, os resultados obtidos mostraram que a técnica de espectroscopia FTIR foi sensível às alterações de conteúdo orgânico no processo de reparação do tecido ósseo, podendo auxiliar com o desenvolvimento de novas técnicas e ferramentas para melhorar a eficiência deste processo. / Bone repair is a critical factor for the success of surgical procedures that require bone cut, and it is desired that it takes place quickly and effectively. The first step for the development of cutting techniques and regenerative therapies is a better understanding of bone repair in structural and molecular level. In this context, the FTIR technique allows one to obtain different information about the structure and composition of mineralized tissue. The main purpose of this project was to verify the effectiveness of FTIR spectroscopy in the characterization of different stages of bone healing process after the removal of a bone piece using two cutting tools: the Er,Cr:YSGG laser or a multilayered carbide bur at high rpm. Two jaw bone fragments were removed from 30 rabbits, and the process of bone repair was studied immediately, 3, 7, 15, 21, and 28 days after the surgery. The FTIR spectroscopy technique was used to acquire the spectral images of different stages of bone healing process, and the ratio of the bone compounds was analyzed using the bands of amide, collagen, carbonate and phosphate of the absorption spectra. Histological analysis was also performed to study the stages of bone repair. The FTIR technique was effective in characterizing the healing process. There was a trend between the proportions of organic and inorganic compounds that were comparable to the one observed in the histological analysis, showing that the FTIR technique is sensitive to changes that occur during the formation of new bone tissue. The results of the histological analysis showed differences in the early stages of bone repair between the cut with the Er,Cr:YSGG laser and the drill. These differences were not detected in FTIR spectroscopy with the used technique. Still, the results show that the FTIR technique is sensitive to changes in the organic content of bone tissue repair process, and it could corroborate to the development of new techniques and tools that improves the efficiency of this process.
18

Atuação de ácido \'beta\'-naftoxiacético, ácido indolbutírico e ácido giberélico na morfogênese de microplantas de abacaxizeiro \"Gomo-de-Mel\" / \'beta\'-Naftoxiacetic acid, indolbutyric acid and acid giberelic action in the pineapple microplants gomo de mel morphogenesis.

Barbosa, Maysa Carvalho 26 February 2010 (has links)
Visando avaliar a atuação dos biorreguladores beta-NOA, AIB e GA3 na morfogênese de microplantas de abacaxi Ananas comosus L. (Merrill) cultivar IAC Gomo-de-Mel estabeleceu-se um experimento com a presença isolada e/ou combinada dos respectivos biorreguladores ao meio de cultura MS. As microplantas foram mantidas em condições de cultura in vitro, com temperatura, luminosidade e fotoperíodo controlados (25 ± 2 C, irradiância de 42 µmol.m-2s-1 e 16 horas, respectivamente) durante 3 meses. Os resultados obtidos com a análise de variância evidenciaram que houve interação do biorregulador de crescimento e o tempo de cultivo para a altura, número de raiz e número de folhas. O beta-NOA induziu a rizogênese foliar nas microplantas a partir de células da bainha do feixe vascular e não apresentou toxicidade nas concentrações utilizadas, ao passo que o AIB mostrou-se mais eficaz para a indução da rizogênese adventícia caulinar. Em relação ao crescimento das microplantas, a ação tanto isolada, como combinada em ambas as concentrações avaliadas de GA3 foram mais eficientes. As análises histológicas evidenciaram alterações no número de estratos da epiderme, hipoderme e mesofilo das folhas cultivadas nos tratamentos com biorreguladores, porém não se verificou alterações citológicas em nenhum dos tratamentos. Acredita-se que a utilização de pulsing seja uma alternativa eficaz para a rizogênese e crescimento em altura das microplantas de abacaxizeiro Gomo-de-mel. / In order to evaluate the action of bioregulators beta-NOA, IBA and GA3 in the pineapple Ananas comosus L. (Merril) cultivar IAC gomo-de-mel microplants morphogenesis an experiment was stablished in order to the presence of the bioregulator alone and in combinations. The microplants were kept in culture in vitro conditions, during 3 months under controlled temperature, light and photoperiod (25 ± 2 C, irradiance de 42 µmol.m- 2s-1 e 16 hours). The analysis of variance showed the interaction interaction between the use of bioregulator and the period of cultivation on hight, number of roots and leaves. The beta-NOA induced leaf rhizogensis in the microplants from the bundle sheath and there was no sign of toxicity with the used concentrations. The IBA showed to be more effective in the adventicious steam rhizogenesis. The isolated and combinated actions of GA3 were the most effective treatment to microplants growing. The histological analysis showed alterations on the epidermis, hypodermis and mesophyll number of layers of the cultivated leaves with this bioregulator, but neither of the treatments showed citological alterations. It is believed that the use of pulsing would be an effective alternative for the rhizogenesis and growing of the gomo de mel pineapple microplants.
19

Estudo da reparação óssea por espectroscopia ATR-FTIR após remoção de fragmento da região mandibular com laser de Er,Cr:YSGG ou broca multilaminada / Study of bone repair by ATR - FTIR spectroscopy technique after the removal of a fragment from jaw region using Er,Cr:YSGG laser or drill

Carolina Benetti 06 August 2014 (has links)
A reparação óssea é um fator crítico para o sucesso de procedimentos odontológicos e ortopédicos que necessitem do corte ósseo, sendo desejado que esta ocorra de forma rápida e eficaz. Uma maior compreensão da reparação óssea em um nível estrutural e molecular é o primeiro passo para o desenvolvimento de técnicas de corte e terapias regenerativas. Neste contexto, a técnica de FTIR possibilita obter informações sobre a estrutura e composição de tecido mineralizado. O principal objetivo deste projeto foi verificar a eficácia da espectroscopia FTIR na caracterização de diferentes estágios da reparação óssea após a realização de remoção óssea utilizando duas ferramentas de corte: o laser de Er,Cr:YSGG ou uma broca carbide multilaminada, em alta rotação. Foi realizada a remoção de dois fragmentos ósseos da mandíbula de 30 coelhos, e o processo de reparação óssea foi estudado imediatamente, 3, 7, 15, 21, e 28 dias após o procedimento cirúrgico. Utilizou-se a técnica de espectroscopia FTIR para a aquisição das imagens espectrais dos diferentes estágios de reparação, e foi analisada a proporção entre os compostos do tecido utilizando as bandas de amidas, colágeno, carbonato e fosfato dos espectros de absorção. Também foi realizada a análise histológica dos mesmos estágios de reparação estudados. A técnica de espectroscopia FTIR se mostrou eficaz na caracterização do processo de reparação óssea. Observou-se uma tendência de aumento na proporção de compostos orgânicos até o Grupo 15D, após o qual houve aumento na proporção de compostos inorgânicos indicando maior mineralização após este período. Os resultados da análise histológica mostraram diferenças nos primeiros estágios de reparação entre o corte ósseo com o laser de Er,Cr:YSGG e a broca em alta rotação. Essas diferenças não foram detectadas na espectroscopia FTIR com as técnicas de análise utilizadas. Ainda assim, os resultados obtidos mostraram que a técnica de espectroscopia FTIR foi sensível às alterações de conteúdo orgânico no processo de reparação do tecido ósseo, podendo auxiliar com o desenvolvimento de novas técnicas e ferramentas para melhorar a eficiência deste processo. / Bone repair is a critical factor for the success of surgical procedures that require bone cut, and it is desired that it takes place quickly and effectively. The first step for the development of cutting techniques and regenerative therapies is a better understanding of bone repair in structural and molecular level. In this context, the FTIR technique allows one to obtain different information about the structure and composition of mineralized tissue. The main purpose of this project was to verify the effectiveness of FTIR spectroscopy in the characterization of different stages of bone healing process after the removal of a bone piece using two cutting tools: the Er,Cr:YSGG laser or a multilayered carbide bur at high rpm. Two jaw bone fragments were removed from 30 rabbits, and the process of bone repair was studied immediately, 3, 7, 15, 21, and 28 days after the surgery. The FTIR spectroscopy technique was used to acquire the spectral images of different stages of bone healing process, and the ratio of the bone compounds was analyzed using the bands of amide, collagen, carbonate and phosphate of the absorption spectra. Histological analysis was also performed to study the stages of bone repair. The FTIR technique was effective in characterizing the healing process. There was a trend between the proportions of organic and inorganic compounds that were comparable to the one observed in the histological analysis, showing that the FTIR technique is sensitive to changes that occur during the formation of new bone tissue. The results of the histological analysis showed differences in the early stages of bone repair between the cut with the Er,Cr:YSGG laser and the drill. These differences were not detected in FTIR spectroscopy with the used technique. Still, the results show that the FTIR technique is sensitive to changes in the organic content of bone tissue repair process, and it could corroborate to the development of new techniques and tools that improves the efficiency of this process.
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Avaliação das condições periodontais clínicas e histológicas em fumantes e não fumantes / Evaluation of clinical and histological periodontal status in smokers and non-smokers

Lussi, Lucinara Ignez Tavares 18 June 2003 (has links)
Condições periodontais clínicas e histológicas foram avaliadas em fumantes e não-fumantes. Participaram do estudo 55 indivíduos, dos quais 29 fumantes e 26 não-fumantes, entre 30 e 50 anos, com média de 40 anos de idade. Os parâmetros clínicos utilizados foram: profundidade de sondagem(PS), índice de placa(IP), índice gengival(IG), índice de sangramento gengival(ISG), nível de inserção clínica (NI) e recessão gengival(R). A análise histológica envolveu histomorfologia e histomorfometria do tecido conjuntivo gengival em área de bolsa periodontal de 10 indivíduos, 5 fumantes e 5 não-fumantes, selecionados aleatoriamente entre os grupos. Também foi considerado o tempo do hábito do fumo, a quantidade de cigarros fumados por dia e a quantidade de dentes ausentes em fumantes. Os resultados obtidos revelaram uma tendência de maiores médias de profundidade de sondagem, nível de inserção clínica e acúmulo de placa em fumantes, maiores médias de índice gengival para nãofumantes, menores médias de índice de sangramento gengival para fumantes e médias similares de recessão gengival entre os grupos. Os efeitos clínicos e histológicos foram menos expressivos em fumantes. Este mascaramento da doença periodontal provocado por reações vasculares, celulares e imunes, e o tempo do vício, podem resultar em prognósticos menos favoráveis da terapia periodontal em fumantes. / Clinical and histological periodontal status were evaluated in smokers and non-smokers. Fifty five subjects took part of the study, 29 smokers and 26 non-smokers, ages ranging from 30 to-50 years, with age average of 40 years. The clinical parameters used were: probing depth(PD), plaque index(PI), gingival index(GI), clinical attachment level (CAL), gingival recession(GR) and gingival bleeding index(GBI). The histological analysis was done by histomorphometry and histomorphology of the gingival connective tissue of the periodontal pocket by 10 subjects, of which 5 were smokers and 5 non-smokers who were randomly selected by the both groups. The time of smoking habit, amounts of cigarette smoked per day and the tooth loss were also considered in smokers. The obtained results showed a tendency of greater averages by probing depth, periodontal attachment level and amount of plaque in smokers, greater average of gingival index for non-smokers, lower average of gingival bleeding for smokers and similar averages of recession in both groups. Histological and clinical effects were less expressive in smokers. This masking of periodontal disease caused by immunological, cellular and vascular reactions, and the time of smoking, can result in less favourable prognosis of the periodontal therapy in smokers.

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