Spelling suggestions: "subject:"morphometric""
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Divergence and reproductive isolation in the bushcricket Mecopoda elongataDutta, Rochishnu January 2015 (has links)
The evolution of isolating mechanisms within a species population impedes gene flow. This allows isolated populations to diverge along different trajectories, which may ultimately lead to the formation of new species. Our attempts to understand the evolution of isolating barriers have benefited enormously from studies of divergent populations that are still recognized as members of the same species. The co-occurrence of five acoustically distinct populations of the bushcricket Mecopoda elongata in south India provided us with the opportunity to study one such divergence of sympatric populations of a single species. In sympatric populations that share identical ecology, sexual selection has the potential to play a prominent role in the maintenance of reproductive isolation. Based on a previous traditional morphometric study, Mecopoda elongata in India were thought to be a morphologically indistinguishable cryptic species complex. The lack of morphological divergence suggests a less significant role of ecology in the divergence of the group. One possibility is that songtypes may be maintained by the preference of Mecopoda elongate females for mating with a specific songtype. In this thesis I show that female phonotaxis to their ‘own’ call has the potential to contribute to behavioural isolation among the songtypes and in particular between two songtypes with overlapping temporal call parameters. This finding is supported by an independent no-choice mating experiment utilizing the same two songtypes. To investigate the cues other than song that Mecopoda elongata females’ may use to exercise preference for their own type, I examined the composition of cuticular lipids in the cuticle and the detailed structure of secondary sexual characters. I was able to differentiate all Mecopoda elongata songtypes with high probability based on CHC profiles and geometric morphometrics of the sub genital plate and cerci. My study reveals that divergence in sexual traits other than acoustic signals, although dramatically less obvious in nature, is present among Mecopoda elongata populations. This provides potential mechanisms for premating isolation among Mecopoda elongata songtypes in the wild suggesting that reproductive isolation is maintained by female preferences for male sexual signals. Additionally, I discovered a parasitoid Tachinid fly responsible for infecting three different songtypes of Mecopoda elongata, namely Double Chirper, Two Part and Helicopter. This Tachinid fly appears to have specialized hearing organ to track down calling Mecopoda elongata males throwing light on potential selection pressure and possible mechanism for Mecopoda elongata song divergence.
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Cognition and morphological brain changes in Charles Bonnet syndromeRussell, Gregor January 2014 (has links)
Charles Bonnet syndrome (CBS) is defined as complex persistent visual hallucinations in the absence of mental disorder. It is associated with advanced age and poor vision. It is common, with prevalence estimates of up to 63% among older people with significant visual impairment. CBS would not be diagnosed in the presence of dementia, but its relationship to milder cognitive impairment is unclear. The few studies that have examined this are underpowered and provide contradictory results. There are 16 case reports of dementia emerging in people with a diagnosis of CBS. These cases raise the possibility of an association between impaired insight at diagnosis of CBS and the subsequent development of dementia. This thesis reports the findings of a prospective cohort study which describes changes in cognitive functioning over one year in patients with CBS and age-matched controls. Participants were recruited from low vision and glaucoma assessment clinics. A clinical assessment was carried out by an old age psychiatrist, and participants had a detailed assessment of visual functioning. This thesis also describes the findings of the first study to use voxel-based morphometry (VBM) to investigate changes in volume of grey and white matter in CBS. Participants were recruited from the same clinics as the cohort study, and underwent MRI scanning on a 1.5T scanner, to a protocol designed to produce 1mm3 voxels. Twelve participants with CBS and ten controls were followed up. Two people in the CBS group developed dementia, while none did in the control group. The CBS group showed a mean change in the score on the Addenbrooke’s cognitive examination (ACE-R) of -3.7 points, compared to a change of +1.4 in the control group. This difference was not statistically significant. The CBS participants performed worse on the verbal fluency item of the ACE-R, a difference which was statistically significant. The VBM analysis was conducted on 11 CBS participants and 11 controls. The CBS group showed an increase in grey matter volume in the right cerebellar hemisphere. This difference retained significance after family-wise error correction, non-stationary correction, and ANCOVA to control for the effects of possible confounders. As far as the author is aware, these are the most methodologically robust studies to date to have investigated cognition and morphological brain changes in CBS. The findings of the cohort study were inconclusive. However, the two cases of dementia in CBS patients add weight to the suspicion that this is a clinically important outcome in the condition, and the finding of abnormalities in frontal lobe testing in participants with CBS fits with a theoretical model of visual hallucination generation. Moreover, this type of research appears to be acceptable to a frail and visually disabled population, and studies powered to investigate this issue more fully would be feasible. The VBM findings report the presence of underlying structural brain abnormalities in CBS, in a region not usually associated with visual hallucinations. Possible links with Lewy body dementia, and implications for theories of visual hallucinations, are discussed.
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Caracterização, isolamento e cultura de espermatogônias primárias de curimbatá, Prochilodus lineatus (Valencienes, 1847). / Characterization, isolation and culture of primary spermatogonias of curimbatá, Prochilodus lineatus (Valencienes, 1847).Gisele Cristiane de Melo Dias 20 March 2015 (has links)
Machos adultos de P. lineatus tiveram suas gônadas processadas de acordo com as rotinas de microscopia de luz e microscopia eletrônica de transmissão. Para a cultura de células, os testículos foram digeridos enzimaticamente, a suspensão testicular foi separada por gradiente descontínuo com Percoll seguido pelo plaqueamento diferencial por adesão e as células foram cultivadas. Foi realizado o método de enriquecimento das espermatogônias por citometria de fluxo. Os testículos apresentam as regiões anterior, média e posterior com distribuição semelhante dos tipos de células, e o diâmetro nuclear das células germinativas diminui significativamente durante a espermatogênese. As espermatogônias cultivadas por 15 dias com meio para proliferação celular resultaram em grandes aglomerados celulares que foram caracterizados com o anti-Vasa, anti-GFRa1 e anti-OCT4. As culturas que receberam o meio para diferenciação celular mostraram processo de proliferação lento das espermatogônias primárias comparado com a cultura que teve o meio indicado para proliferação celular. / Adult males of P. lineatus had their gonads used according routines of light microscopy and transmission electron microscopy. For cell culture, the testes were enzymatically digested; testicular suspension was separated by discontinuous gradient with Percoll followed by adhesion differential plating and the cells were cultured. The enrichment of the spermatogonia was carried by flow cytometry. The testes present three regions with similar distribution of cell types, and nuclear diameter of germ cells decreases significantly during spermatogenesis. The spermatogonia cultured for 15 days with medium for cell proliferation, resulted in large cell agglomerates which were characterized with the antibodies anti-Vasa, anti-GFRa1 and anti-anti-OCT4. The cultures that receiving medium for cell differentiation showed slow proliferation process of primary spermatogonia compared to cell culture medium suggestive for cell differentiation.
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RELAÇÃO DO VOLUME TESTICULAR COM O NÍVEL SÉRICO DE TESTOSTERONA E CRESCIMENTO CORPORAL EM BRAHMAN DOS OITO AOS 18 MESES DE IDADE / RELATIONSHIP OF TESTICULAR VOLUME WITH SERUM TESTOSTERONE LEVEL AND BODY GROWTH IN BRAHMAN FROM 8 TO 18 MONTHS OF AGEMiyasaki, Alex Arikawa 25 June 2014 (has links)
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Alex Miyasaki.pdf: 314698 bytes, checksum: 1d8bbeb1da7a5e1f383fc57d9361d819 (MD5)
Previous issue date: 2014-06-25 / Aimed to study the relationship of testicular volume with serum testosterone level and body growth in Brahman cattle from 8 to 18 months of age, during the weaning period, kept at pasture in collective weight gain. Cattle (n = 40) aged 259.76 ± 26.15 days and weight of 239.71 ± 33.94 kg , were evaluated every 56 days during 294 days, totaling six measurements for body weight (BW), scrotal circumference (SC), thoracic perimeter (PT), body height (HC), body length (BL), body mass index (BMI), right testicular length (RTL) and left (LTL), right testicular height (RTH) and left (LTH), daily weight gain (DWG), testicular volume (TV) and serum testosterone (T). Was used analysis of variance followed by Tukey 5%. Correlations employed the method of Pearson. There were higher (P < 0.05) the third harvest (12.85 ± 0.87 months) in front for GMD x T. and higher ratings (P < 0.05) for BW, SC, EN, HC, BL, BMI, RTL, LTL, RTH, LTH and TV were obtained from the fourth harvest (14.72 ± 0.87 months). There was a correlation between T = 0.38 x PT (P <0.01); HC x T = 0.38 (P<0.01); HTD x T = 0.23 (P<0.05); HTE x T = 0.21 (P<0.01) and T x VT = 0.22 (P < 0.008). It is suggested to use the calculation of testicular volume in breeding soundness evaluation of young bulls, whose significant increase of the same may serve as a parameter for estimating the rapid increase in testosterone production, which was present at about 3.7 months before detection of a significant increase in testicular volume. / Objetivou-se estudar a relação do volume testicular com o nível sérico de testosterona e crescimento corporal em bovinos da raça Brahman dos oito aos 18 meses de idade, no período da desmama ao sobreano, mantidos à pasto em prova coletiva de ganho de peso. Os bovinos (n=40) com idade de 259,76±26,15 dias e peso de 239,71±33,94 kg, foram avaliados a cada 56 dias, durante 294 dias, totalizando seis colheitas para peso corpóreo (PC), circunferência escrotal (CE), perímetro torácico (PT), altura de cernelha (HC), comprimento corporal (CC), índice de massa corpórea (IMC), comprimento testicular direito (CTD) e esquerdo (CTE), altura testicular direito (HTD) e esquerdo (HTE), ganho médio diário de peso corpóreo (GMD), volume testicular (VT) e níveis séricos de testosterona (T). Utilizou-se a análise de variância, seguida por Tukey a 5%. Para as correlações empregou-se o método de Pearson. Houve superioridade (P<0,05) da terceira colheita (12,85 ± 0,87 meses de idade) em diante para GMD e T. Médias superiores (P<0,05) para PC, CE, PT, HC, CC, IMC, CTD, CTE, HTD, HTE e VT foram obtidas a partir da quarta colheita (14,72 ± 0,87 meses de idade). Houve correlações entre T x PT=0,38 (P<0,01); T x HC=0,38 (P<0,01); T x HTD=0,23 (P<0,05); T x HTE=0,21 (P<0,01) e T x VT=0,22 (P<0,008). Sugere-se a adoção do cálculo do volume testicular na avaliação andrológica de tourinhos jovens, cuja elevação significativa do mesmo pode servir como parâmetro para estimar o rápido aumento da produção de testosterona, a qual se fez presente por volta de 3,7 meses antes da detecção do significativo aumento do volume testicular.
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RELAÇÃO DO VOLUME TESTICULAR COM O NÍVEL SÉRICO DE TESTOSTERONA E CRESCIMENTO CORPORAL EM BRAHMAN DOS OITO AOS 18 MESES DE IDADE / RELATIONSHIP OF TESTICULAR VOLUME WITH SERUM TESTOSTERONE LEVEL AND BODY GROWTH IN BRAHMAN FROM 8 TO 18 MONTHS OF AGEMiyasaki, Alex Arikawa 25 June 2014 (has links)
Made available in DSpace on 2016-07-18T17:53:14Z (GMT). No. of bitstreams: 1
Alex Miyasaki.pdf: 314698 bytes, checksum: 1d8bbeb1da7a5e1f383fc57d9361d819 (MD5)
Previous issue date: 2014-06-25 / Aimed to study the relationship of testicular volume with serum testosterone level and body growth in Brahman cattle from 8 to 18 months of age, during the weaning period, kept at pasture in collective weight gain. Cattle (n = 40) aged 259.76 ± 26.15 days and weight of 239.71 ± 33.94 kg , were evaluated every 56 days during 294 days, totaling six measurements for body weight (BW), scrotal circumference (SC), thoracic perimeter (PT), body height (HC), body length (BL), body mass index (BMI), right testicular length (RTL) and left (LTL), right testicular height (RTH) and left (LTH), daily weight gain (DWG), testicular volume (TV) and serum testosterone (T). Was used analysis of variance followed by Tukey 5%. Correlations employed the method of Pearson. There were higher (P < 0.05) the third harvest (12.85 ± 0.87 months) in front for GMD x T. and higher ratings (P < 0.05) for BW, SC, EN, HC, BL, BMI, RTL, LTL, RTH, LTH and TV were obtained from the fourth harvest (14.72 ± 0.87 months). There was a correlation between T = 0.38 x PT (P <0.01); HC x T = 0.38 (P<0.01); HTD x T = 0.23 (P<0.05); HTE x T = 0.21 (P<0.01) and T x VT = 0.22 (P < 0.008). It is suggested to use the calculation of testicular volume in breeding soundness evaluation of young bulls, whose significant increase of the same may serve as a parameter for estimating the rapid increase in testosterone production, which was present at about 3.7 months before detection of a significant increase in testicular volume. / Objetivou-se estudar a relação do volume testicular com o nível sérico de testosterona e crescimento corporal em bovinos da raça Brahman dos oito aos 18 meses de idade, no período da desmama ao sobreano, mantidos à pasto em prova coletiva de ganho de peso. Os bovinos (n=40) com idade de 259,76±26,15 dias e peso de 239,71±33,94 kg, foram avaliados a cada 56 dias, durante 294 dias, totalizando seis colheitas para peso corpóreo (PC), circunferência escrotal (CE), perímetro torácico (PT), altura de cernelha (HC), comprimento corporal (CC), índice de massa corpórea (IMC), comprimento testicular direito (CTD) e esquerdo (CTE), altura testicular direito (HTD) e esquerdo (HTE), ganho médio diário de peso corpóreo (GMD), volume testicular (VT) e níveis séricos de testosterona (T). Utilizou-se a análise de variância, seguida por Tukey a 5%. Para as correlações empregou-se o método de Pearson. Houve superioridade (P<0,05) da terceira colheita (12,85 ± 0,87 meses de idade) em diante para GMD e T. Médias superiores (P<0,05) para PC, CE, PT, HC, CC, IMC, CTD, CTE, HTD, HTE e VT foram obtidas a partir da quarta colheita (14,72 ± 0,87 meses de idade). Houve correlações entre T x PT=0,38 (P<0,01); T x HC=0,38 (P<0,01); T x HTD=0,23 (P<0,05); T x HTE=0,21 (P<0,01) e T x VT=0,22 (P<0,008). Sugere-se a adoção do cálculo do volume testicular na avaliação andrológica de tourinhos jovens, cuja elevação significativa do mesmo pode servir como parâmetro para estimar o rápido aumento da produção de testosterona, a qual se fez presente por volta de 3,7 meses antes da detecção do significativo aumento do volume testicular.
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Comprehensive assessment and characterization of pulmonary acinar morphometry using multi-resolution micro x-ray computed tomographyKizhakke Puliyakote, Abhilash Srikumar 01 May 2016 (has links)
The characterization of the normal pulmonary acinus is a necessary first step in understanding the nature of respiratory physiology and in assessing the etiology of pulmonary pathology. Murine models play a vital role in the advancement of current understanding of the dynamics of gas exchange, particle deposition and the manifestations of diseases such as COPD, Cystic Fibrosis and Asthma. With the advent of interior tomography techniques, high-resolution micro computed tomography (μCT) systems provide the ability to nondestructively assess the pulmonary acinus at micron and sub-micron resolutions. With the application of Systematic Uniform Random Sampling (SURS) principles applied to in-situ fixed, intact, ex-vivo lungs, we seek to characterize the structure of pulmonary acini in mice and study the variations across dimensions of age, location within the lung and strain phenotypes.
Lungs from mice of three common research strains were perfusion fixed in-situ, and imaged using a multi-resolution μCT system (Micro XCT 400, Zeiss Inc.). Using lower resolution whole lung images, SURS methods were used for identification of region-specific acini for high-resolution imaging. Acinar morphometric metrics included diameters, lengths and branching angles for each alveolar duct and total path lengths from entrance of the acinus to the terminal alveolar sacs. In addition, other metrics such as acinar volume, alveolar surface area and surface area/volume ratios were assessed.
A generation-based analysis demonstrated significant differences in acinar morphometry across young and old age groups and across the three strains. The method was successfully adapted to large animals and the data from one porcine specimen has been presented. The registration framework provides a direct technique to assess acinar deformations and provides critical physiological information about the state of alveolar ducts and individual alveoli at different phases of respiration.
The techniques presented here allow us to perform direct assessment of the three-dimensional structure of the pulmonary acinus in previously unavailable detail and present a unique technique for comprehensive quantitative analysis. The acinar morphometric parameters will help develop improved mathematical and near-anatomical models that can accurately represent the geometric structure of acini, leading to improved assessment of flow dynamics in the normal lung.
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Sledování vztahu mezi asymetrií skeletu a měkkých tkání obličeje na základě výpočetní tomografie / Monitoring of the relationship between the asymmetry of facial skeleton and the soft tissues based on computed tomographySkryjová, Zuzana January 2021 (has links)
The human face is not perfectly symmetrical, slight asymmetries commonly occur in every individual across all populations. The aim of the work was to monitor the asymmetry on the entire surface of the soft and hard tissues of the heads of individuals with respect to age and sexual dimorphism. The follow-up goal was then to evaluate the difference in asymmetry between the tissues. The material for the work was a transverse set of CT images of the adult Czech population in the age range of 21-84 years. Individuals were divided according to gender into 50 men and 48 women and according to age into groups up to 39 years, 40-59 years and over 60 years. Geometric morphometry methods (CPD - DCA, asymmetry analysis, per vertex T-test, superprojection methods) were used for data analysis. The results were visualized using color maps and significance maps that show asymmetry and statistical significance. The variability of the file was analyzed by principal component analysis. The results of the evaluation of hard tissues showed a right protrusion on the anterior and lateral surfaces of the skull, in both men and women at all age intervals. This asymmetry was statistically very significant, in contrast to the posterior region, which was evaluated protrusion on the left side and had lower p-value. On the soft...
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Regulace objemu astrocytů v průběhu stárnutí / Astrocyte volume regulation during agingEliášová, Barbora January 2015 (has links)
Astrocytes, as one of the glial cell types, have many important functions in healthy functioning of the central nervous system (CNS) but also in its pathology. Since they play a key role in maintenance of ionic, neurotransmitter and water homeostasis in CNS, they possess the ability to regulate their volume. Hypo- or hyperosmotic stress can trigger regulatory volume decrease or increase in astrocytes in order to stabilize their volume. During aging, astrocytes undergo many changes together with the rest of the brain. In order to determine whether these alterations involve also regulatory volume mechanisms, we employed three dimensional morphometry, which comprises confocal microscope scanning of fluorescently labelled astrocytes in brain slices of EGFP/GFAP mice and quantification of astrocyte volume during different pathological stimuli. Time-dependent volume changes of hippocampal astrocytes were recorded while applying either hypoosmotic solution or solution with high extracellular potassium concentration. In the four different age groups studied in the experiment, several differences in volume changes were discovered together with some sex-dependent alterations in astrocyte volume. Additionally, in accordance with previous studies, two subpopulation of astrocytes were identified using...
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Morfometrická analýza povrchu patra u pacientů s celkovým jednostranným rozštěpem rtu a patra. / Morphometric analysis of palatal surface in patients with unilateral complete cleft lip and palate.Rusková, Hana January 2011 (has links)
Thesis deals with the study of palate morphology and variability of patients with UCLP, using modern methods of geometric morphometrics. Dental plaster casts of UCLP patients (average age 14,8) and the control group (average age 14,7) were used for evaluation. The models were scanned using a 3D scanner. For evaluation of total variability of patients with orofacial clefts, previously rated dental casts of BCLP patients (whose age ranged from 12,1 to 16,5) were also included. All patients were operated and treated at The Clinic of Plastic Surgery in Prague. The results are in accordance with literature, which describes the basic size and shape differences in the morphology of the palate in different types of clefts (e.g. narrowing of the palate in UCLP and BCLP and asymmetry of palatal vault in UCLP). Using "Dense correspondense models analysis" average surface models were computed and new informations about the shape and premaxila position were gained. Different location and slope of the palate in different types of clefts and within control group were detected by superimposition of average models and FESA. UCLP palate have typically asymetric palate vault with a maximum height in front of the cleft palate and at the back in the side without malformations. Variability of the shape of palate for each group...
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La narcolepsie et l’hypersomnie idiopathique : une analyse par morphométrie cérébraleZhao, Jean-Louis 04 1900 (has links)
Introduction : La narcolepsie et l'hypersomnie idiopathique sont des troubles d'hypersomnie centrale peu compris, caractérisés par une somnolence diurne excessive causant des perturbations majeures au niveau du fonctionnement diurne et de la qualité de vie. Bien que certains aspects cliniques soient propres à chaque condition, plusieurs caractéristiques se chevauchent et ces dernières demeurent très difficile à diagnostiquer adéquatement. Le manque de distinction entre les troubles d'hypersomnolence centrale est extrêmement problématique, limitant la compréhension des mécanismes physiopathologiques sous- jacents.
Objectif : À l'aide de la morphométrie cérébrale, l'objectif de l'étude est d'établir des différences anatomiques (c.-à-d., épaisseur corticale, volume sous-cortical) entre la narcolepsie avec cataplexie (NT1), la narcolepsie sans cataplexie (NT2), l'hypersomnie idiopathique (HI) et des participants en santé contrôles dans diverses régions du cerveau qui sont fonctionnellement liées au sommeil et au maintien de l'éveil. Méthodes : Une séquence d’acquisition d’images IRM anatomiques pondérées en T1 fut acquise sur 15 patients NT1, 15 NT2, 15 HI et 15 participants contrôles en santé (n = 60). Les images anatomiques furent traitées avec la suite logicielle FreeSurfer (FreeSurfer version 6.0.1) afin d'obtenir des mesures d'épaisseur corticale et de volume sous-cortical. Les mesures morphométriques obtenus pour différentes régions furent comparées entre les groupes par ANOVAs, ajustées pour l'âge.
Résultats : Les résultats ont démontré une réduction volumétrique de la matière grise dans plusieurs structures sous-corticales associées au sommeil et au maintien de l'éveil dont l'hypothalamus et l'amygdale pour les patients NT1 et les patients NT2, comparés aux participants contrôles en santé. Les patients HI quant à eux n'ont pas démontré de différence volumétrique au niveau de l'hypothalamus comparativement aux participants contrôles, mais plutôt une diminution du volume de l'amygdale et du noyau accumbens, des structures associées à un réseau fonctionnel modulant la vigilance. Aucune différence significative d'épaisseur corticale n'a été retrouvée entre les groupes.
Conclusion : Les résultats montrent des changements neuroanatomiques distincts entre les patients NT1 et HI, suggérant des mécanismes physiopathologiques différents et soulignent le phénotype hétérogène des patients NT2. / Introduction : Narcolepsy and idiopathic hypersomnia are poorly understood central disorders of
hypersomnolence characterized by excessive daytime sleepiness leading to severe daytime disturbances
and poor quality of life. Although some clinical features are specific to each condition, many
characteristics overlap, and a reliable diagnosis remains difficult to achieve. The lack of clinical distinction
between central disorders of hypersomnolence is extremely problematic and hinders the understanding
of their underlying pathophysiological mechanisms.
Objective : Using brain morphometry, the objective of this study is to establish anatomical differences
(i.e., cortical thickness and subcortical volume) between narcolepsy with cataplexy (NT1), narcolepsy
without cataplexy (NT2), idiopathic hypersomnia (HI) and healthy controls in brain regions involved in the
modulation of sleep and wakefulness.
Methods : T1-weighted MRI sequences were acquired in 15 NT1 patients, 15 NT2, 15 HI and 15 healthy
controls (n = 60). Anatomical images were preprocessed using the FreeSurfer software package
(FreeSurfer version 6.0.1) to obtain measures of cortical thickness and subcortical volume. Group
differences in brain morphometric measurements acquired for different brain regions were analyzed
using ANOVAs, adjusted for age.
Results : Results displayed reduced gray matter volume in subcortical structures associated with the
modulation of sleep and wakefulness, including the hypothalamus and the amygdala in NT1 and NT2
patients, compared to healthy controls. On the other hand, HI patients did not show volume changes in
the hypothalamus compared to healthy controls, but instead showed a volume reduction of the amygdala
and the nucleus accumbens, both structures associated with a functional network involved in the
modulation of alertness. No significant group difference in cortical thickness was found.
Conclusion : These results show distinct neuroanatomical changes between NT1 patients and HI patients,
suggesting separate pathophysiological mechanisms and underline the heterogeneous phenotype of NT2
patients.
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