962 resultados para morphological and anatomical aspects


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The abdominal muscles have an important role in control and movement of the lumbar spine and pelvis. Given there is new evidence of morphological and functional differences between distinct anatomical regions of the abdominal muscles, this study investigated whether there are regional differences in postural activity of these muscles and whether recruitment varies between different body positions. Eleven subjects with no history of low back pain that affected function or for which they sought treatment participated in the study. Electromyographic (EMG) activity of the upper, middle and lower regions of transversus abdominis (TrA), the middle and lower regions of obliquus internus abdominis (OI) and the middle region of obliquus externus abdominis (OE) was recorded using intramuscular electrodes. All subjects performed rapid, unilateral shoulder flexion in standing and six subjects also moved their upper limb in sitting. There were regional differences in the postural responses of TrA with limb movement. Notably, the onset of EMG of the upper region was later than that of the lower and middle regions. There were no differences in the EMG onsets of lower and middle TrA or OI. The postural responses of the abdominal muscles were also found to differ between body positions, with recruitment delayed in sitting compared to standing. This study showed that there is regional differentiation in TrA activity with challenges to postural control and that body position influences the postural responses of the abdominal muscles. These results may reflect variation in the contribution of abdominal muscle regions to stability of the trunk. (c) 2004 Elsevier B.V. All rights reserved.

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The dramatic effects of brain damage can provide some of the most interesting insights into the nature of normal cognitive performance. In recent years a number of neuropsychological studies have reported a particular form of cognitive impairment where patients have problems recognising objects from one category but remain able to recognise those from others. The most frequent ‘category-specific’ pattern is an impairment identifying living things, compared to nonliving things. The reverse pattern of dissociation, i.e., an impairment recognising and naming nonliving things relative to living things, has been reported albeit much less frequently. The objective of the work carried out in this thesis was to investigate the organising principles and anatomical correlates of stored knowledge for categories of living and nonliving things. Three complementary cognitive neuropsychological research techniques were employed to assess how, and where, this knowledge is represented in the brain: (i) studies of normal (neurologically intact) subjects, (ii) case-studies of neurologically impaired patients with selective deficits in object recognition, and (iii) studies of the anatomical correlates of stored knowledge for living and nonliving things on the brain using magnetoencephalography (MEG). The main empirical findings showed that semantic knowledge about living and nonliving things is principally encoded in terms of sensory and functional features, respectively. In two case-study chapters evidence was found supporting the view that category-specific impairments can arise from damage to a pre-semantic system, rather than the assumption often made that the system involved must be semantic. In the MEG study, rather than finding evidence for the involvement of specific brain areas for different object categories, it appeared that, when subjects named and categorised living and nonliving things, a non-differentiated neural system was involved.

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The exponential growth of studies on the biological response to ocean acidification over the last few decades has generated a large amount of data. To facilitate data comparison, a data compilation hosted at the data publisher PANGAEA was initiated in 2008 and is updated on a regular basis (doi:10.1594/PANGAEA.149999). By January 2015, a total of 581 data sets (over 4 000 000 data points) from 539 papers had been archived. Here we present the developments of this data compilation five years since its first description by Nisumaa et al. (2010). Most of study sites from which data archived are still in the Northern Hemisphere and the number of archived data from studies from the Southern Hemisphere and polar oceans are still relatively low. Data from 60 studies that investigated the response of a mix of organisms or natural communities were all added after 2010, indicating a welcomed shift from the study of individual organisms to communities and ecosystems. The initial imbalance of considerably more data archived on calcification and primary production than on other processes has improved. There is also a clear tendency towards more data archived from multifactorial studies after 2010. For easier and more effective access to ocean acidification data, the ocean acidification community is strongly encouraged to contribute to the data archiving effort, and help develop standard vocabularies describing the variables and define best practices for archiving ocean acidification data.

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Purpose: Recent studies have documented a link between axial myopia and ciliary muscle morphology; yet, the variation in biometric characteristics of the emmetropic ciliary muscle are not fully known. Ciliary muscle morphology, including symmetry, was investigated between both eyes of emmetropic participants and correlated to ocular biometric parameters. Methods: Anterior segment optical coherence tomography (Zeiss, Visante) was utilised to image both eyes of 49 emmetropic participants (mean spherical equivalent refractive error (MSE) ≥ -0.55; < +0.75 D), aged 19 to 26 years. High resolution images were obtained of nasal and temporal aspects of the ciliary muscle in the relaxed state. MSE of both eyes was recorded using the Grand Seiko WAM 5500; axial length (AXL), anterior chamber depth (ACD) and lens thickness (LT) of the right eye were obtained using the Haag-streit Lenstar LS 900 biometer. A bespoke semi-objective analysis programme was used to measure a range of ciliary muscle parameters. Results: Temporal ciliary muscle overall length (CML) was greater than nasal CML, in both eyes (right: 3.58 ± 0.40 mm and 3.85 ± 0.39 mm for nasal and temporal aspects, respectively, P < 0.001; left: 3.65 ± 0.35 mm and 3.88 ± 0.41 mm for nasal and temporal aspects, respectively, P < 0.001). Temporal ciliary muscle thickness (CMT) was greater than nasal CMT at 2 mm and 3 mm from the scleral spur (CM2 and CM3, respectively) in each eye (right CM2: 0.29 ± 0.05 mm and 0.32 ± 0.05 mm for nasal and temporal aspects, respectively, P < 0.001; left CM2: 0.30 ± 0.05 mm and 0.32 ± 0.05 mm for nasal and temporal aspects, respectively, P < 0.001; right CM3: 0.13 ± 0.05 mm and 0.16 ± 0.04 mm for nasal and temporal aspects, respectively, P < 0.001; left CM3: 0.14 ± 0.04 mm and 0.17 ± 0.05 mm for nasal and temporal aspects, respectively, P < 0.001). AXL was positively correlated with ciliary muscle anterior length (AL) (e.g. P < 0.001, r2 = 0.262 for left temporal aspect), CML (P = 0.003, r2 = 0.175 for right nasal aspect) and ACD (P = 0.01, r2 = 0.181). Conclusions: Morphological characteristics of the ciliary muscle in emmetropic eyes display high levels of symmetry between the eyes. Greater CML and AL are linked to greater AXL and ACD, indicating ciliary muscle growth with normal ocular development.

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Calcitic belemnite rostra are usually employed to perform paleoenvironmental studies based on geochemical data. However, several questions, such as their original porosity and microstructure, remain open, despite they are essential to make accurate interpretations based on geochemical analyses.This paper revisits and enlightens some of these questions. Petrographic data demonstrate that calcite crystals of the rostrum solidum of belemnites grow from spherulites that successively develop along the apical line, resulting in a “regular spherulithic prismatic” microstructure. Radially arranged calcite crystals emerge and diverge from the spherulites: towards the apex, crystals grow until a new spherulite is formed; towards the external walls of the rostrum, the crystals become progressively bigger and prismatic. Adjacent crystals slightly vary in their c-axis orientation, resulting in undulose extinction. Concentric growth layering develops at different scales and is superimposed and traversed by a radial pattern, which results in the micro-fibrous texture that is observed in the calcite crystals in the rostra.Petrographic data demonstrate that single calcite crystals in the rostra have a composite nature, which strongly suggests that the belemnite rostra were originally porous. Single crystals consistently comprise two distinct zones or sectors in optical continuity: 1) the inner zone is fluorescent, has relatively low optical relief under transmitted light (TL) microscopy, a dark-grey color under backscatter electron microscopy (BSEM), a commonly triangular shape, a “patchy” appearance and relatively high Mg and Na contents; 2) the outer sector is non-fluorescent, has relatively high optical relief under TL, a light-grey color under BSEM and low Mg and Na contents. The inner and fluorescent sectors are interpreted to have formed first as a product of biologically controlled mineralization during belemnite skeletal growth and the non-fluorescent outer sectors as overgrowths of the former, filling the intra- and inter-crystalline porosity. This question has important implications for making paleoenvironmental and/or paleoclimatic interpretations based on geochemical analyses of belemnite rostra.Finally, the petrographic features of composite calcite crystals in the rostra also suggest the non-classical crystallization of belemnite rostra, as previously suggested by other authors.

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Broad nosed caiman are ectotherm sauropsids that naturally experience long fasting intervals. We have studied the postprandial responses by measuring oxygen consumption using respirometry, the size changes of the duodenum, the distal small intestine, and the liver, using repeated non-invasive ultrasonography, and by investigating structural changes on the level of tissues and cells by using light- and electron microscopy. The caimans showed the same rapid and reversible changes of organ size and identical histological features, down to the ultrastructure level, as previously described for other ectothermic sauropsids. We found a configuration change of the mucosa epithelium from pseudostratified during fasting to single layered during digestion, in association with hypertrophy of enterocytes by loading them with lipid droplets. Similar patterns were also found for the hepatocytes of the liver. By placing the results of our study in comparative relationship and by utilizing the phylogenetic bracket of crocodiles, birds and squamates, we suggest that the observed features are plesiomorphic characters of sauropsids. By extending the comparison to anurans, we suggest that morphological and physiological adjustments to feeding and fasting described here may have been a character of early tetrapods. In conclusion, we suggest that the ability to tolerate long fasting intervals and then swallow a single large meal as described for many sit-an-wait foraging sauropsids is a functional feature that was already present in ancestral tetrapods.

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Nowadays, the varicose ulcers (VUs) are one of the most worrying leg ulcers and are an important problem in global public health, with high costs related to the treatment and its complications. Moreover, the quality of life (QOL) of the patient could be affected by pain, sleep disorders, functional impairment, depression and isolation. The VUs patient care is complex and it is necessary to know the aspects that contribute to the healing process for developing effective strategies. The members of the multidisciplinary health team should identify sociodemographic, clinical and care aspects that interfere in tissue repair and therefore impacting the QOL. Self-efficacy, adherence to treatment and self-esteem are other important aspects also related to healing and QOL, with implications for health care and the multidisciplinary team. To sum up, the use of multidisciplinary protocols allows the systematization of care for people with VUs in order to standardize therapeutic interventions with the aim to decrease the healing process time and, as a consequence, to improve the QOL.

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Genetic diversity estimates based on morphological and molecular data can provide different information on the relationship between cultivars of a species. This study aimed to develop new microsatellite markers as additional tools in genetic studies on mangoes (Mangifera indica L.), and to analyze the genetic variability of 20 mango cultivars based on morphological descriptors and microsatellite markers. We aimed to better understand the cultivars enhanced breeding histories and to support crossbreeding planning. Positive clones were selected from a DNA library enriched for microsatellite regions for sequencing and primer design. Four plants of each of the 20 accessions were used for observations, based on 48 morphological descriptors. Twenty accessions were analyzed using 27 microsatellite markers, of which 16 were developed during this study. The clusters, based on the morphological descriptors by Ward - MLM strategy and the microsatellite markers, suggested that Brazilian mango cultivars have extensive genetic diversity and are related to cultivars with different provenances, demonstrating their different enhanced breeding histories.

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The enteric nervous system (ENS) modulates a number of digestive functions including well known ones, i.e. motility, secretion, absorption and blood flow, along with other critically relevant processes, i.e. immune responses of the gastrointestinal (GI) tract, gut microbiota and epithelial barrier . The characterization of the anatomical aspects of the ENS in large mammals and the identification of differences and similarities existing between species may represent a fundamental basis to decipher several digestive GI diseases in humans and animals. In this perspective, the aim of the present thesis is to highlight the ENS anatomical basis and pathological aspects in different mammalian species, such as horses, dogs and humans. Firstly, I designed two anatomical studies in horses:  “Excitatory and inhibitory enteric innervation of horse lower esophageal sphincter”.  “Localization of 5-hydroxytryptamine 4 receptor (5-HT4R) in the equine enteric nervous system”. Then I focused on the enteric dysfunctions, including:  A primary enteric aganglionosis in horses: “Extrinsic innervation of the ileum and pelvic flexure of foals with ileocolonic aganglionosis”.  A diabetic enteric neuropathy in dogs: “Quantification of nitrergic neurons in the myenteric plexus of gastric antrum and ileum of healthy and diabetic dogs”.  An enteric neuropathy in human neurological patients: “Functional and neurochemical abnormalities in patients with Parkinson's disease and chronic constipation”. The physiology of the GI tract is characterized by a high complexity and it is mainly dependent on the control of the intrinsic nervous system. ENS is critical to preserve body homeostasis as reflect by its derangement occurring in pathological conditions that can be lethal or seriously disabling to humans and animals. The knowledge of the anatomy and the pathology of the ENS represents a new important and fascinating topic, which deserves more attention in the veterinary medicine field.

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This thesis investigates the morphological variations of fibular extremities in humans and non-human hominids using a 3D Geometric Morphometric approach. The study has three objectives: (1) to assess the shape, form, and size variations of fibular epiphyses within the human species, highlighting sexually dimorphic features; (2) to explore interpopulation variability of fibular extremities from the Upper Paleolithic to the 20th century, comparing subsistence, mobility, and lifestyles; and (3) to examine interspecific variations in fibular ends, testing potential associations with locomotor and positional behavior among extant hominid taxa. In terms of intraspecific variations, sex-related differences in fibular form and size were observed, suggesting distinct functional requirements for the lower limb between sexes. Interpopulation variations revealed a decline in activity level over time, influenced by terrain and footwear use. Hunter-gatherer groups exhibited greater joint mobility, loading, and range of motion compared to sedentary pre- and post-industrial populations. Interspecific variations demonstrated significant morphological differences among hominid taxa, indicating functional implications related to both phylogeny and specific loading patterns on the lower limb. The study identified features indicative of bipedalism in humans, as well as shared characteristics among non-human great apes. Furthermore, distinguishing features were found between Asian and African apes, along with unique morphological signals associated with distinct positional behavior in each hominid taxa. By comprehensively analyzing fibular morphology, this research sheds light on the importance of this bone in knee support, ankle stabilization, and overall locomotor function. The findings contribute to our understanding of the evolutionary and functional aspects of the fibula across human populations and non-human hominids throughout history.

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The reproductive capacity between Triatoma lenti and Triatoma sherlocki was observed in order to verify the fertility and viability of the offspring. Cytogenetic, morphological and morphometric approaches were used to analyze the differences that were inherited. Experimental crosses were performed in both directions. The fertility rate of the eggs in crosses involving T. sherlocki females was 65% and 90% in F1 and F2 offspring, respectively. In reciprocal crosses, it was 7% and 25% in F1 and F2 offspring, respectively. The cytogenetic analyses of the male meiotic process of the hybrids were performed using lacto-acetic orcein, C-banding and Feulgen techniques. The male F1 offspring presented normal chromosome behavior, a finding that was similar to those reported in parental species. However, cytogenetic analysis of F2 offspring showed errors in chromosome pairing. This post-zygotic isolation, which prevents hybrids in nature, may represent the collapse of the hybrid. This phenomenon is due to a genetic dysregulation that occurs in the chromosomes of F1. The results were similar in the hybrids from both crosses. Morphological features, such as color and size of connexive and the presence of red-orange rings on the femora, were similar to T. sherlocki, while wins size was similar to T. lenti in F1 offspring. The eggshells showed characteristics that were similar to species of origin, whereas the median process of the pygophore resulted in intermediate characteristics in the F1 and a segregating pattern in F2 offspring. Geometric morphometric techniques used on the wings showed that both F1 and F2 offspring were similar to T. lenti. These studies on the reproductive capacity between T. lenti and T. sherlocki confirm that both species are evolutionarily closed; hence, they are included in the brasiliensis subcomplex. The extremely reduced fertility observed in the F2 hybrids confirmed the specific status of the species that were analyzed.

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The current dominance of African runners in long-distance running is an intriguing phenomenon that highlights the close relationship between genetics and physical performance. Many factors in the interesting interaction between genotype and phenotype (eg, high cardiorespiratory fitness, higher hemoglobin concentration, good metabolic efficiency, muscle fiber composition, enzyme profile, diet, altitude training, and psychological aspects) have been proposed in the attempt to explain the extraordinary success of these runners. Increasing evidence shows that genetics may be a determining factor in physical and athletic performance. But, could this also be true for African long-distance runners? Based on this question, this brief review proposed the role of genetic factors (mitochondrial deoxyribonucleic acid, the Y chromosome, and the angiotensin-converting enzyme and the alpha-actinin-3 genes) in the amazing athletic performance observed in African runners, especially the Kenyans and Ethiopians, despite their environmental constraints.

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To evaluate vaginal microbiological and functional aspects in women with and without premature ovarian failure (POF) and the relationship with sexual function. A cross-sectional study of 36 women with POF under hormonal therapy who were age-matched with 36 women with normal gonadal function. The vaginal tropism was assessed through hormonal vaginal cytology, vaginal pH and vaginal health index (VHI). Vaginal flora were assessed by the amine test, bacterioscopy and culture for fungi. Sexual function was evaluated through the questionnaire Female Sexual Function Index (FSFI). Women in both groups were of similar age and showed similar marital status. The two groups presented vaginal tropic scores according to the VHI but the tropism was worse among women in the POF group. No difference was observed with respect to hormonal cytology and pH. Vaginal flora was similar in both groups. Women with POF showed worse sexual performance with more pain and poorer lubrication than women in the control group. The VHI, the only parameter evaluated showing statistical difference between the groups, did not correlate with the domains of pain and lubrication in the FSFI questionnaire. These findings suggest that the use of systemic estrogen among women with POF is not enough to improve complaints of lubrication and pain despite conferring similar tropism and vaginal flora. Other therapeutic options need to be evaluated.

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Minor structural alterations of the vocal fold cover are frequent causes of voice abnormalities. They may be difficult to diagnose, and are expressed in different manners. Cases of intracordal cysts, sulcus vocalis, mucosal bridge, and laryngeal micro-diaphragm form the group of minor structural alterations of the vocal fold cover investigated in the present study. The etiopathogenesis and epidemiology of these alterations are poorly known. To evaluate the existence and anatomical characterization of minor structural alterations in the vocal folds of newborns. 56 larynxes excised from neonates of both genders were studied. They were examined fresh, or defrosted after conservation via freezing, under a microscope at magnifications of 25× and 40×. The vocal folds were inspected and palpated by two examiners, with the aim of finding minor structural alterations similar to those described classically, and other undetermined minor structural alterations. Larynges presenting abnormalities were submitted to histological examination. Six cases of abnormalities were found in different larynges: one (1.79%) compatible with a sulcus vocalis and five (8.93%) compatible with a laryngeal micro-diaphragm. No cases of cysts or mucosal bridges were found. The observed abnormalities had characteristics similar to those described in other age groups. Abnormalities similar to sulcus vocalis or micro-diaphragm may be present at birth.