Morphometric Study (morphometric + study)

Distribution by Scientific Domains
Distribution within Life Sciences


Selected Abstracts


Conformation of the Equine Skull: A Morphometric Study

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 4 2006
K. E. Evans
Summary There is a lack of an established method for quantifying equine skull morphology. This study proposes a method that is valid for use on both live and deceased horses. A total of nine head measurements (skull length, cranial length, nasal length, ratio of cranial:nasal length, cranial width, zygomatic width, mandibular depth, nasal profile area, cranial profile area) and six indices (skull index, cranial index, nasal index, mandibular index, nasal profile index, cranial profile index) were recorded from 30 horses from a variety of breeds whilst the soft tissues of the head were intact. A line was drawn level with the palpable notches caudal to the caudal lacrimal process of each orbit to estimate the suture line of the nasal and frontal bones and distinguish between the neurocranium and splanchnocranium. There were positive correlations between many of the head measurements. This method also illustrated significant differences in the skull morphology of three breeds (Arabians, thoroughbreds and standardbreds). [source]


Morphometric study of Ecklonia cava (Laminariales, Phaeophyta) sporophytes in two localities with different temperature conditions

PHYCOLOGICAL RESEARCH, Issue 3 2002
Yukihiko Serisawa
SUMMARY Sporophytes of Ecklonia cava Kjellman (Laminariales, Phaeophyta) were collected seasonally from within 3,4 replicate, 1-m2 quadrates, haphazardly placed in dense assemblages at 6,9 m depth in Tei, Tosa Bay (southern Japan; water temperature 15,29°C) from 1995 to 1996, and in Nabeta Bay, Shimoda (central Japan; water temperature 13,25°C) from 1996 to 1997. Growth rings were checked for all samples and mean values of each biometric parameter of sporophytes 1-year-old and over were compared. The plant length (stipe length + primary blade length) was always shorter in Tei sporophytes (24,52 cm) than Nabeta sporophytes (70,100 cm), the difference being mainly owing to the shorter stipe length in Tei sporophytes (7,14 cm) than in Nabeta sporophytes (54,83 cm). However, the primary blade length was sometimes longer in Tei sporophytes (12,38 cm) than in Nabeta sporophytes (14,21 cm). Stipe diameter, longest bladelet length and primary blade width were mostly less in Tei sporophytes (8.6,12.4 mm, 5.5,7.0 cm and 23.4,38.0 cm, respectively) than Nabeta sporophytes (16.4,20.2 mm, 9.2,12.0 cm and 43.0,52.6 cm, respectively). Nevertheless, the number of bladelets of sporophytes from Tei (15,28) and Nabeta (18,29) were within the same range. At Tei, 32,43% of the sporophytes had wrinkled blades in summer and autumn, whereas wrinkled primary blades or bladelets were not observed in Nabeta sporophytes throughout the experimental period. These morphometric differences of E. cava between the two localities are suggested to be dependent on environmental factors, especially seawater temperature. [source]


Regional gray matter reduction and theory of mind deficit in the early phase of schizophrenia: a voxel-based morphometric study

ACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2009
R. Herold
Objective:, We tested the association between theory of mind (ToM) performance and structural changes in the brains of patients in the early course of schizophrenia. Method:, Voxel-based morphometry (VBM) data of 18 patients with schizophrenia were compared with those of 21 controls. ToM skills were assessed by computerized faux pas (FP) tasks. Results:, Patients with schizophrenia performed significantly worse in FP tasks than healthy subjects. VBM revealed significantly reduced gray matter density in certain frontal, temporal and subcortical regions in patients with schizophrenia. Poor FP performance of schizophrenics correlated with gray matter reduction in the left orbitofrontal cortex and right temporal pole. Conclusion:, Our data indicate an association between poor ToM performance and regional gray matter reduction in the left orbitofrontal cortex and right temporal pole shortly after the onset of schizophrenia. [source]


No change in the structure of the brain in migraine: a voxel-based morphometric study

EUROPEAN JOURNAL OF NEUROLOGY, Issue 1 2003
M. S. Matharu
Migraine is a common, disabling form of primary neurovascular headache. For most of the twentieth century it was regarded as a vascular headache whose primary pathophysiology lay in the cranial vasculature. Functional brain imaging using positron emission tomography has demonstrated activation of the rostral brain stem in acute migraine. Voxel-based morphometry is a new fully automated whole brain technique that is sensitive to subtle macroscopic and mesoscopic structural differences between groups of subjects. In this study 11 patients suffering from migraine with aura (10 females, one male: 23,52 years, mean 31); 11 controls (10 females, one male: 23,52, mean 31); 17 patients with migraine without aura (16 females, one male: 24,57, mean 34); 17 controls (16 females, one male: 24,57, mean 34) were imaged with high resolution volumetric magnetic resonance imaging. There was no significant difference in global grey or white matter volumes between either patients with migraine and controls, or patients with aura and without aura. This study did not show any global or regional macroscopic structural difference between patients with migraine and controls, with migraine sufferers taken as homogenous groups. If structural changes are to be found, other methods of phenotyping migraine, such as by genotype or perhaps treatment response, may be required to resolve completely whether there is some subtle structural change in the brain of patients with migraine. [source]


A voxel-based morphometry study of frontal gray matter correlates of impulsivity,

HUMAN BRAIN MAPPING, Issue 4 2009
Koji Matsuo
Abstract Impulsivity is a personality trait exhibited by healthy individuals, but excessive impulsivity is associated with some mental disorders. Lesion and functional neuroimaging studies indicate that the ventromedial prefrontal region (VMPFC), including the orbitofrontal cortex (OFC), anterior cingulate cortex (ACC) and medial prefrontal cortex, and the amygdala may modulate impulsivity and aggression. However, no morphometric study has examined the association between VMPFC and impulsivity. We hypothesized that healthy subjects with high impulsivity would have smaller volumes in these brain regions compared with those with low impulsivity. Sixty-two healthy subjects were studied (age 35.4 ± 12.1 years) using a 1.5-T MRI system. The Barratt impulsiveness scale (BIS) was used to assess impulsivity. Images were processed using an optimized voxel-based morphometry (VBM) protocol. We calculated the correlations between BIS scale scores and the gray matter (GM) and white matter (WM) volumes of VMPFC and amygdala. GM volumes of the left and right OFC were inversely correlated with the BIS total score (P = 0.04 and 0.02, respectively). Left ACC GM volumes had a tendency to be inversely correlated with the BIS total score (P = 0.05). Right OFC GM volumes were inversely correlated with BIS nonplanning impulsivity, and left OFC GM volumes were inversely correlated with motor impulsivity. There were no significant WM volume correlations with impulsivity. The results of this morphometry study indicate that small OFC volume relate to high impulsivity and extend the prior finding that the VMPFC is involved in the circuit modulating impulsivity. Hum Brain Mapp 2009. © 2008 Wiley-Liss, Inc. [source]


A geometric morphometric study of regional differences in the ontogeny of the modern human facial skeleton,

JOURNAL OF ANATOMY, Issue 3 2002
Una Strand Viğarsdóttir
Abstract This study examines interpopulation variations in the facial skeleton of 10 modern human populations and places these in an ontogenetic perspective. It aims to establish the extent to which the distinctive features of adult representatives of these populations are present in the early post natal period and to what extent population differences in ontogenetic scaling and allometric trajectories contribute to distinct facial forms. The analyses utilize configurations of facial landmarks and are carried out using geometric morphometric methods. The results of this study show that modern human populations can be distinguished based on facial shape alone, irrespective of age or sex, indicating the early presence of differences. Additionally, some populations have statistically distinct facial ontogenetic trajectories that lead to the development of further differences later in ontogeny. We conclude that population-specific facial morphologies develop principally through distinctions in facial shape probably already present at birth and further accentuated and modified to variable degrees during growth. These findings raise interesting questions regarding the plasticity of facial growth patterns in modern humans. Further, they have important implications in relation to the study of growth in the face of fossil hominins and in relation to the possibility of developing effective discriminant functions for the identification of population affinities of immature facial skeletal material. Such tools would be of value in archaeological, forensic and anthropological applications. The findings of this study underline the need to examine more deeply, and in more detail, the ontogenetic basis of other causes of craniometric variation, such as sexual dimorphism and hominin species differentiation. [source]


Separation between the digestive and the respiratory lumina during the human embryonic period: morphometric study along the tracheo-oesophageal septum

JOURNAL OF ANATOMY, Issue 1 2001
JOSEP NEBOT-CEGARRA
An isolated tracheo-oesophageal fistula could be caused by close proximity of the epithelia of both organs (O'Rahilly & Müller, 1984; Kluth et al. 1987) at certain embryonic stages, the most frequent location being the tracheal bifurcation. Thus the relative position and degree of separation between the digestive and the respiratory tubes throughout their development may be relevant to the origin of this anomaly. The aim of this study was to analyse along the different segments of the tracheo-oesophageal septum (TES) where the closest relationship between both lumina occurred and what degree of separation was present at each segment. Computer imaging techniques were applied on cross sections of a graded series of normal human embryos (Carnegie stages (CS) 13,23). In addition, the differentiation of the primitive TES was also studied (from CS 12) by light microscopy. Between CS 13 and 16 both tubes tended to separate (phase of separation), principally at the proximal segments of the laryngopharyngeal and the tracheo-oesophageal portions of the TES. During this phase the separation between the trachea and oesophagus was wider than between the larynx and pharynx. From CS 17 to CS 23 the digestive and respiratory lumina reached their widest separation at different levels of the laryngopharyngeal portion. Below these levels they tended to come closer together, principally at the proximal segment of the tracheo-oesophageal portion, but also at the distal part of the laryngopharyngeal portion. During this phase of approximation they reached their closest relationship at the proximal (CS 17) and the distal (from CS 18) segments of the tracheo-oesophageal portion. When finally the distal segment of the trachea (which includes the bifurcation) comes closest to the oesophagus, the coats of both organs have already undergone an appreciable differentiation. According to these observations, the origin of the most frequent isolated tracheo-oesophageal fistula at the bifurcation region could not be explained from the normal development of the TES. [source]


Renal cortex remodeling in nitric oxide deficient rats treated with enalapril

JOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 1 2004
Noemi Barbuto
Abstract The kidney NO synthase is one of the most important renal controlling systems. This paper aims the quantification of renal cortical components involved in blood pressure regulation under NOs blockade. Spontaneous hypertensive rats (SHRs) are submitted to chronic blockade of NOs by L-nitro-arginine-methyl-ester (L-NAME) and an ACE inhibitor (enalapril) in comparison with the normotensive Wistar rats. Twenty SHRs and 5 Wistar rats were divided in 5 groups and observed for 21 days for blood pressure (BP) and serum creatinine: control Wistar (5) (C-W), control SHR (5) (C-SHR), L-SHR (5) - received L-NAME 30 mg/kg/day, L+E-SHR (5) - received L-NAME and Enalapril maleate 15 mg/kg/day, E-SHR (5) - received Enalapril maleate. A quantitative morphometric study (glomerular density, QA[g1], interstitium volume density, Vv[i], tubular surface and length densities, Sv[t] and Lv[t]) were performed at the end. The BP reached 226±15 mmHg in L-SHR group. The BP difference between the L-SHR and the C-SHR groups was significant from the first week while the E-SHR group became significant from the second week. At the end of the experiment the BP of the E-SHR group was similar to the BP in the C-W group. The QA[g1] was similar among C-SHR, L-SHR and L+E-SHR groups and no difference was found between E-SHR and C-W groups. In the L-SHRs serum creatinine was greatly increased, and microscopy showed thickening of arteriolar tunica media with an increase of the wall-to-lumen ratio, perivascular fibrosis, inflammatory infiltrated, tubular atrophy and interstitial fibrosis with focal segmental glomerulosclerosis. The use of enalapril was not completely efficient in reducing BP and morphological injury when the hypertension of SHRs was increased with the NOs blockade suggesting that NO deficiency-induced hypertension is not entirely mediated by the RAAS. [source]


The significance of wing pattern diversity in the Lycaenidae: mate discrimination by two recently diverged species

JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 5 2002
J. A. Fordyce
Abstract Closely related species of lycaenid butterflies are determinable, in part, by subtle differences in wing pattern. We found that female wing patterns can act as an effective mate-recognition signal in some populations of two recently diverged species. In field experiments, we observed that males from a Lycaeides idas population and an alpine population of L. melissa preferentially initiate courtship with conspecific females. A morphometric study indicated that at least two wing pattern elements were important for distinguishing the two species: hindwing spots and orange crescent-shaped pattern elements called aurorae. We deceived male L. idas into initiating courtship with computer generated paper models of heterospecific females when these pattern elements were manipulated, indicating that the wing pattern elements that define the diversity of this group can be effective mate recognition signals. [source]


EARLY DEVELOPMENT PATTERN OF THE BROWN ALGA ECTOCARPUS SILICULOSUS (ECTOCARPALES, PHAEOPHYCEAE) SPOROPHYTE,

JOURNAL OF PHYCOLOGY, Issue 5 2008
Aude Le Bail
The distant phylogenetic position of brown macroalgae from the other multicellular phyla offers the opportunity to study novel and alternative developmental processes involved in the establishment of multicellularity. At present, however, very little information is available about developmental patterning in this group. Ectocarpus siliculosus (Dillwyn) Lyngb. has uniseriate filaments and displays one of the simplest architectures in the Phaeophyceae. The aim of this study was to decipher the morphogenetic steps that lead to the development of the Ectocarpus sporophyte. We carried out a detailed morphometric study of the events that occurred between gamete germination and the 100-cell stage. This analysis was performed on two ecologically distant isolates to assess plasticity in developmental patterning within this species. Cell sizes were measured in both isolates, allowing the definition of two main cell types based on their shape (round and elongated). On average, the filament is composed of about 40% round cells, which are present in the central region of the filament, but different combinations of the two cell types within filaments were observed and quantified. Young sporophytes grew apically, with elongated cells progressively differentiating into round cells. Secondary filaments emerged preferentially on round cells, primarily from the older central cells. Statistical analyses showed that the pattern of branching was regulated to ensure a stereotyped architecture. This description of the developmental patterning during the growth of the E. siliculosus sporophyte will serve as a base for more detailed studies of development, in this species and in brown algae in general. [source]


Idiopathic salivary gland enlargement (sialadenosis) in dogs: a microscopic study

JOURNAL OF SMALL ANIMAL PRACTICE, Issue 6 2000
M. Sozmen
A histological, histochemical and morphometric study was performed on submandibular salivary glands from 13 dogs which had presented with a submandibular mass or swelling that proved to be a portion of non-inflammatory and non-neoplastic submandibular salivary gland. There were no consistent changes in lectin-binding histochemistry or immunohistochemical expression of various cell markers, and, in most cases, there was no measurable difference in acinar size in the affected gland. The possible explanation for the clinical salivary gland enlargement is therefore unclear. [source]


Computerised morphometric study of the paraurethral tissue in young and elderly women

NEUROUROLOGY AND URODYNAMICS, Issue 6 2002
M. Verelst
Abstract Aim. Changes in structural support of the urethra and bladder neck have been proposed to be among the most important factors in the pathogenesis of stress urinary incontinence. In this context, we histologically investigated the paraurethral area in continent women to quantify the relative distribution of connective tissue, smooth muscle, vessels, nerves, and striated muscle. Previously published literature gives only descriptive evaluations of the relative distribution of these tissue components. Methods. We used a computerised morphometric method, which allowed us to estimate the paraurethral tissue distribution in a more objective way. The material was obtained by dissection during autopsy in five premenopausal and five postmenopausal women. Results. Paraurethral tissue consisted of 56% connective tissue (SD, 5%), 30% smooth muscle (SD, 5%), 11% blood vessel (SD, 6%), 2% striated muscle (SD, 3%), and 1% nerves (SD, 1%). We also found that the distribution of different tissue components along the length of the urethra did not differ at a statistically significant level. Furthermore, there was a statistically significant difference in the amount of connective tissue and blood vessels in the postmenopausal women compared with the premenopausal women. Conclusions. The present study shows that the paraurethral area is built of heterogeneous tissue with small changes in its composition along the course of urethra. Increase in connective tissue was found to be the dominating change in the process of ageing. Neurourol. Urodynam. 21:529,533, 2002. © 2002 Wiley-Liss, Inc. [source]


A quantitative and morphometric study of mast cells in cutaneous leishmaniasis

PARASITE IMMUNOLOGY, Issue 11-12 2008
F. F. TUON
SUMMARY Background,Mast cells (MCs) are related with healing process in chronic inflammatory diseases, although in cutaneous leishmaniasis (CL) its importance is unknown. The aim of this study was to determine the correlation of MC with clinical findings in patients with the localized form of CL. Methods,A cohort of 85 patients with CL was evaluated. MCs count was performed in pre-treatment biopsies and correlation with clinical findings and Leishmania species determined by PCR were performed. Results,The MCs count in patients with CL caused by Leishmania (V.) braziliensis was 14·3 ± 9·8 cells/mm2, and 7·0 ± 6·5 cells/mm2 in patients with L. (L.) amazonensis (P < 0·05). The linear regression of MCs count with the age showed a tendency of cell number decreasing, according to ageing of the patient (r2 = 0·05; P < 0·05). The association of disease's duration and MCs count was positive (r2 = 0·11; P < 0·05). There was not any association of MCs count with number of lesions neither with Leishmania antigen expression. The MCs count was higher in patients with earlier healing after treatment (P < 0·05). Conclusion,MC can be important in CL and related with healing lesion. [source]


Geometric morphometric study of population variation in indigenous southern African crania

AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 1 2007
D. Franklin
Much of our understanding of population variation in southern Africa is derived from traditional morphometric research. In the search for new perspectives, this paper reports on new geometric morphometric data examining cranial variation in 12 modern human populations from southern Africa. In total, 298 male Bantu-speaking individuals were studied. In addition, a small Khoisan (Khoikhoi and San) series was also examined. The purpose of this study was to investigate Khoisan-Bantu morphological similarities and differences, and to examine variation within both the Bantu-speaking and Khoisan populations. The three-dimensional coordinates of 96 landmarks were analyzed, using the shape-analysis software morphologika. Interpopulation variation was examined by calculating Procrustes distances between groups; a cluster analysis was then used to summarize phenetic relationships. A principal components analysis explored the relationships between populations; shape differences were visualized and explored using three-dimensional rendered models, and further interpreted using thin-plate splines. Morphological differences are present within and between the crania of Bantu-speaking and Khoisan individuals. The Khoisan demonstrate features (e.g., a pentagonoid vault, more rounded forehead contour, and a small and less prognathic face) that clearly distinguish them from Bantu-speaking populations. Although southern African Bantu-speaking populations are clearly closely related, they show population-specific features (e.g., the crania of more southerly populations (Xhosa, Southern Sotho, and Zulu) are characteristically more brachycephalic and less prognathic). This study suggests that differential admixture with adjacent Khoisan peoples has contributed to diversity within southern African Bantu-speaking populations. Am. J. Hum. Biol. 19:20,33, 2007. © 2006 Wiley-Liss, Inc. [source]


Reduced gray matter volume of dorsal cingulate cortex in patients with obsessive,compulsive disorder: A voxel-based morphometric study

PSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 5 2010
Ryohei Matsumoto MD
Aims:, Previous morphometric studies using magnetic resonance imaging (MRI) have revealed structural brain abnormalities in obsessive,compulsive disorder (OCD). The aim of the present study was to investigate the alterations in brain structure of patients with OCD using a voxel-based morphometry (VBM) method. Methods:, Sixteen patients with OCD free of comorbid major depression, and 32 sex- and age-matched healthy subjects underwent MRI using a 1.5-T MR scanner. OCD severity was assessed with the Yale,Brown Obsessive,Compulsive Scale (mean ± SD: 22 ± 7.6; range: 7,32). MR images were spatially normalized and segmented using the VBM5 package (http://dbm.neuro.uni-jena.de/vbm/). Statistical analysis was performed using statistical parametric mapping software. Results:, Significant reductions in regional gray matter volume were detected in the left caudal anterior cingulate cortex and right dorsal posterior cingulate cortex in the patients with OCD as compared to healthy controls (uncorrected, P < 0.001). No significant differences in white matter volumes were observed in any brain regions of the patients. No significant correlation between Yale,Brown Obsessive,Compulsive Scale score and regional gray matter or white matter volume was observed. Conclusions:, Regional gray matter alteration in the dorsal cingulate cortex, which is suggested to play a role in non-emotional cognitive processes, may be related to the pathophysiology in OCD. [source]


Successfully overcoming the inhibitory impact of the "forget" instruction: A voxel-based morphometric study of directed forgetting

PSYCHOPHYSIOLOGY, Issue 5 2009
Anna Nowicka
Abstract In directed-forgetting studies, test items are followed by an instruction either to "remember" or to "forget" (F). Many to-be-forgotten (TBF) stimuli are not retrieved at the recognition phase. However, some subjects are able to correctly recollect a high number of TBF stimuli. We examined whether this ability is reflected in the structure of brain regions involved in memory and the control of retrieval processes. In subjects with high recognition rates for TBF stimuli, voxel-based morphometry revealed increased gray matter (GM) volume in the left ventrolateral prefrontal cortex (VLPFC) and the right hippocampus (H). GM volume in these regions correlated positively with the TBF recognition rate. No significant differences were detected in subjects who forgot many TBF stimuli. Our findings indicate that the right H and left VLPFC are of particular relevance in releasing TBF items from inhibition caused by the F instruction. [source]


Morphometric variation in the papionin muzzle and the biochronology of the South African Plio-Pleistocene karst cave deposits

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2010
Christopher C. Gilbert
Abstract Papionin monkeys are widespread, relatively common members of Plio-Pleistocene faunal assemblages across Africa. For these reasons, papionin taxa have been used as biochronological indicators by which to infer the ages of the South African karst cave deposits. A recent morphometric study of South African fossil papionin muzzle shape concluded that its variation attests to a substantial and greater time depth for these sites than is generally estimated. This inference is significant, because accurate dating of the South African cave sites is critical to our knowledge of hominin evolution and mammalian biogeographic history. We here report the results of a comparative analysis of extant papionin monkeys by which variability of the South African fossil papionins may be assessed. The muzzles of 106 specimens representing six extant papionin genera were digitized and interlandmark distances were calculated. Results demonstrate that the overall amount of morphological variation present within the fossil assemblage fits comfortably within the range exhibited by the extant sample. We also performed a statistical experiment to assess the limitations imposed by small sample sizes, such as typically encountered in the fossil record. Results suggest that 15 specimens are sufficient to accurately represent the population mean for a given phenotype, but small sample sizes are insufficient to permit the accurate estimation of the population standard deviation, variance, and range. The suggestion that the muzzle morphology of fossil papionins attests to a considerable and previously unrecognized temporal depth of the South African karst cave sites is unwarranted. Am J Phys Anthropol 2010. © 2009 Wiley-Liss, Inc. [source]


Comparative study of brain morphology in Mecp2 mutant mouse models of Rett syndrome

THE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 1 2008
Nadia P. Belichenko
Abstract Rett syndrome (RTT) is caused by mutations in the X-linked gene MECP2. While patients with RTT show widespread changes in brain function, relatively few studies document changes in brain structure and none examine in detail whether mutations causing more severe clinical phenotypes are linked to more marked changes in brain structure. To study the influence of MeCP2-deficiency on the morphology of brain areas and axonal bundles, we carried out an extensive morphometric study of two Mecp2-mutant mouse models (Mecp2B and Mecp2J) of RTT. Compared to wildtype littermates, striking changes included reduced brain weight (,13% and ,9%) and the volumes of cortex (,11% and ,7%), hippocampus (both by ,8%), and cerebellum (,12% and 8%) in both mutant mice. At 3 weeks of age, most (24 of 47) morphological parameters were significantly altered in Mecp2B mice; fewer (18) were abnormal in Mecp2J mice. In Mecp2B mice, significantly lower values for cortical area were distributed along the rostrocaudal axis, and there was a reduced length of the olfactory bulb (,10%) and periaqueductal gray matter (,16%). In Mecp2J mice, while there was significant reduction in rostrocaudal length of cortex, this parameter was also abnormal in hippocampus (,10%), periaqueductal gray matter (,13%), fimbria (,18%), and anterior commissure (,10%). Our findings define patterns of Mecp2 mutation-induced changes in brain structure that are widespread and show that while some changes are present in both mutants, others are not. These observations provide the underpinning for studies to further define microarchitectural and physiological consequences of MECP2 deficiency. J. Comp. Neurol. 508:184,195, 2008. © 2008 Wiley-Liss, Inc. [source]


Canine Spinal Cord Neuron and Axon Myelin Sheath Morphometry

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2006
A. C. De Francischini Carvalho
Summary This inedited morphometric study has been developed from healthy canine spinal cord neuron cytoplasm and nucleus, and white matter axonal myelin sheath, from cervical, thoracic and lumbar regions. For the morphometric study, the parameters were area, perimeter, maximum and minimum diameters and roundness for neurons and myelin thickness for axon. For each parameter, 300 neurons were analysed. The results revealed that lumbar neurons had the highest mean values for the analysed parameters, indicating the presence of large neurons in this region, with large axons as a result of myelin thickness, which is proportional to axon calibre. We conclude that these morphometric results can contribute for the establishment of normal patterns, for canine spinal cord cervical, thoracic and lumbar segments. [source]


The Effect of Testosterone on Gastrocnemius Muscle Fibres in Growing and Adult Male and Female Rats: A Histochemical, Morphometric and Ultrastructural Study,

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2 2003
. Üstünel
Summary In this study, the effect of testosterone on gastrocnemius muscle fibres in growing and adult rats (male and female) was examined using histochemical, morphometric and ultrastructural techniques. After physiological saline (PS), olive oil (OvO) or olive oil + testosterone (OvOT) injections on 72 rats (growing and mature, 36 male and 36 female), the sample tissues of fibre types of the gastrocnemius muscle taken were examined by histochemical [alkaline adenosine triphosphatase (alk-ATPase), acid ATPase (ac-ATPase)], morphometric and ultrastructural techniques. In PS-injected control groups, the gastrocnemius muscle of both sexes contained all the fibre types studied [slow-oxidative muscle fibres (type I), fast-oxidative glycolytic muscle fibres (type IIA) and fast-glycolytic muscle fibres (type IIB)]. The type I fibres had the smallest diameter, type IIA had a medium diameter and type IIB fibres had the largest diameter. In OvO-injected groups, it was observed that the OvO had little effect on the gastrocnemius muscles of either sex, although there was significant enlargement of type IIB fibres. After the injection of OvOT, hypertrophy of muscle fibres was determined by morphometric study. The biggest increase in diameter was on type I fibres. In addition, degenerations on some mitochondria, accumulation of lipid droplets on type I and type II fibres, an increase in glycogen particles, bifurcation of myofibrils, an increase in the number and diameter of units resembling T tubules and an increase in ribosomal content were also observed in the same group by transmission electron microscope. Consequently, it was determined that testosterone can induce protein synthesis in gastrocnemius muscle fibres, and induces changes in shape and size, and also can change the appearance and the number of fibres. [source]


Thalamic atrophy associated with painful osteoarthritis of the hip is reversible after arthroplasty: A longitudinal voxel-based morphometric study

ARTHRITIS & RHEUMATISM, Issue 10 2010
Stephen E. Gwilym
Objective Voxel-based morphometry (VBM) is a method of assessing brain gray matter volume that has previously been applied to various chronic pain conditions. From this previous work, it appears that chronic pain is associated with altered brain morphology. The present study was undertaken to assess these potential alterations in patients with painful hip osteoarthritis (OA). Methods We studied 16 patients with unilateral right-sided hip pain, before and 9 months after hip arthroplasty. This enabled comparison of gray matter volume in patients with chronic musculoskeletal pain versus healthy controls, as well as identification of any changes in volume following alleviation of pain (after surgery). Assessment involved self-completion questionnaires to assess pain, function, and psychosocial variables, and magnetic resonance imaging scanning of the brain for VBM analysis. Results Significant differences in brain gray matter volume between healthy controls and patients with painful hip arthritis were seen. Specifically, areas of the thalamus in patients with chronic OA pain exhibited decreased gray matter volume. Furthermore, when these preoperative changes were compared with the brain morphology of the patients 9 months after surgery, the areas of reduced thalamic gray matter volume were found to have "reversed" to levels seen in healthy controls. Conclusion Our findings confirm that gray matter volume decreases within the left thalamus in the presence of chronic pain and disability in patients with hip OA. The results also show that these thalamic volume changes reverse after hip arthroplasty and are associated with decreased pain and increased function. These findings have potential implications with regard to optimizing the timing of orthopedic interventions such as arthroplasty. [source]


Influence of previous frost damage on tree growth and insect herbivory of Eucalyptus globulus globulus

AUSTRAL ECOLOGY, Issue 5 2001
Vivien P. Thomson
Abstract The plant stress hypothesis suggests that some herbivores favour stressed plants, whereas the plant vigour hypothesis proposes that other herbivores prefer vigorous plants. The effects of a prior stress, that of frost damage, were examined on the subsequent growth of Eucalyptus globulus globulus and on the response of insect herbivores. Frost damage affected tree growth by reducing new leaf area and increasing specific leaf area (SLA). However, herbivore abundance was not affected by prior frost damage. Two feeding trials using Anoplognathus chloropyrus and Hyalarcta huebneri and a morphometric study of Ctenarytaina eucalypti were conducted to assess the performance of herbivores on trees that had suffered more or less frost damage. Consumption by A. chloropyrus and H. huebneri was unaffected by foliage origin (damaged versus healthy). Hyalarcta huebneri grew faster when fed leaves from previously damaged trees, and C. eucalypti from previously damaged trees were larger than those from healthy trees. Enhanced insect performance on frost damaged plants may have resulted from the high specific leaf area (most likely thinner) leaves. The herbivore abundance data did not support the hypothesis that previously frost damaged plants are preferred by insects. However, increased growth of H. huebneri and larger body size of C. eucalypti on damaged trees indicates that previously stressed trees may produce leaves of higher nutritional value. [source]


A morphometric study of the inferior orbital fissure using three-dimensional anatomical landmarks: Application to orbital surgery

CLINICAL ANATOMY, Issue 6 2009
Mehmet Asim Ozer
Abstract The inferior orbital fissure (IOF) is an important structure during orbital surgery, however, neither its anatomical features nor the procedures necessary to expose the IOF have been examined in detail. A morphometric analysis of the IOF was performed on 232 orbits using computer software. The longest and shortest borders of the IOF were 18.2 ± 4.9 and 1.9 ± 1.3 mm, respectively. The outer and the inner angles were 138.9 ± 32.7° and 38.4 ± 24.7°, respectively. The perimeter of the IOF was 50.6 ± 13.5 mm and its area was 61.3 ± 39.1 mm2. Eight types of IOF were observed. Type 1 IOF was observed in 42.2% and the Type 2 IOF was identified in 15.9%. A statistically significant relation was found between the longest edge and area and the widest edge and area of the IOF. The findings of our study suggest that the removal of the lateral wall should begin inferiorly, just lateral to the IOF and extended superolaterally. These data may be useful during surgical approaches to the orbit. Clin. Anat. 22:649,654, 2009. © 2009 Wiley-Liss, Inc. [source]