Brain Segments Research Articles

P025 - A study of general health status and depression in multiple sclerosis patients and its relation with some of their individual characteristics in the Urmia City, Islamic Republic of Iran

Introduction Mental health is a branch of general health that mostly discusses about decreasing psychological disorders in community. Somatic illness is known as a prominent risk factor affecting psychological health. Multiple sclerosis is classified in central nervous system disorders that destroys different segments of brain and spinal cord, by immune system attacks. Depression is associated with most of multiple sclerosis patients and unfortunately suicidal thoughts is obvious in these patients. This problem effects cognitive abilities and quality of life of patients. Materials and method In this analytic/descriptive study, 142 multiple sclerosis sufferers admitted in Imam Khomeini Hospital, Neurology Department of Urmia University of Medical Science, were evaluated after randomized selection. Then the patients were educated about questionnaire. Data collection was carried out using 2 questionnaires, one General Health Questionnaire GHQ-28 and other Beck Depression Questionnaire BDI and demographic characteristics. The main objective of this study was general health and depression status determination in multiple sclerosis sufferers. Results and conclusion The determination of a significant association with age, sex, occupation, duration, treatment and stage of disorder with general health status, concerned with correlation of general health status and personal characteristics of patients is a difficult task to be performed. However, it was associated with education level and was statistically significant at P=0.01 Mental health is a branch of general health that mostly discusses about decreasing psychological disorders in community. Somatic illness is known as a prominent risk factor affecting psychological health. Multiple sclerosis is classified in central nervous system disorders that destroys different segments of brain and spinal cord, by immune system attacks. Depression is associated with most of multiple sclerosis patients and unfortunately suicidal thoughts is obvious in these patients. This problem effects cognitive abilities and quality of life of patients. In this analytic/descriptive study, 142 multiple sclerosis sufferers admitted in Imam Khomeini Hospital, Neurology Department of Urmia University of Medical Science, were evaluated after randomized selection. Then the patients were educated about questionnaire. Data collection was carried out using 2 questionnaires, one General Health Questionnaire GHQ-28 and other Beck Depression Questionnaire BDI and demographic characteristics. The main objective of this study was general health and depression status determination in multiple sclerosis sufferers. The determination of a significant association with age, sex, occupation, duration, treatment and stage of disorder with general health status, concerned with correlation of general health status and personal characteristics of patients is a difficult task to be performed. However, it was associated with education level and was statistically significant at P=0.01

An exceptionally preserved arthropod cardiovascular system from the early Cambrian

The assumption that amongst internal organs of early arthropods only the digestive system withstands fossilization is challenged by the identification of brain and ganglia in early Cambrian fuxianhuiids and megacheirans from southwest China. Here we document in the 520-million-year-old Chengjiang arthropod Fuxianhuia protensa an exceptionally preserved bilaterally symmetrical organ system corresponding to the vascular system of extant arthropods. Preserved primarily as carbon, this system includes a broad dorsal vessel extending through the thorax to the brain where anastomosing branches overlap brain segments and supply the eyes and antennae. The dorsal vessel provides segmentally paired branches to lateral vessels, an arthropod ground pattern character, and extends into the anterior part of the abdomen. The addition of its vascular system to documented digestive and nervous systems resolves the internal organization of F. protensa as the most completely understood of any Cambrian arthropod, emphasizing complexity that had evolved by the early Cambrian.

Complex Regional Pain Syndrome Type I Affects Brain Structure in Prefrontal and Motor Cortex

The complex regional pain syndrome (CRPS) is a rare but debilitating pain disorder that mostly occurs after injuries to the upper limb. A number of studies indicated altered brain function in CRPS, whereas possible influences on brain structure remain poorly investigated.We acquired structural magnetic resonance imaging data from CRPS type I patients and applied voxel-by-voxel statistics to compare white and gray matter brain segments of CRPS patients with matched controls. Patients and controls were statistically compared in two different ways: First, we applied a 2-sample ttest to compare whole brain white and gray matter structure between patients and controls. Second, we aimed to assess structural alterations specifically of the primary somatosensory (S1) and motor cortex (M1) contralateral to the CRPS affected side. To this end, MRI scans of patients with left-sided CRPS (and matched controls) were horizontally flipped before preprocessing and region-of-interest-based group comparison. The unpaired ttest of the “non-flipped” data revealed that CRPS patients presented increased gray matter density in the dorsomedial prefrontal cortex. The same test applied to the “flipped” data showed further increases in gray matter density, not in the S1, but in the M1 contralateral to the CRPS-affected limb which were inversely related to decreased white matter density of the internal capsule within the ipsilateral brain hemisphere. The gray-white matter interaction between motor cortex and internal capsule suggests compensatory mechanisms within the central motor system possibly due to motor dysfunction. Altered gray matter structure in dorsomedial prefrontal cortex may occur in response to emotional processes such as pain-related suffering or elevated analgesic top-down control.

Cloud computing for brain segmentation - a perspective from the technology and evaluations

This paper examines how cloud computing can be used in the area of brain segmentation with regard to satisfactory technical and user evaluations. It explains eleven APIs associated with each brain segment and the process of capturing data for each segment. Functionality and experiments associated with each API are discussed. Dancing is to capture data more easily. Results are used to explain why some segments are more active in dancing, with two evaluations undertaken. The first evaluation is the use of brain segmentations developed for medical cloud computing education (MCCE) and results confirm that cloud computing offers a 20% improvement in learning satisfaction. The second evaluation is focused on recapturing a lost skill. Results confirm that volunteers have their heartbeat, blood pressure, emotion, body coordination and vision at their peak. Benefits of using cloud brain segmentation technology are presented to illustrate positive impacts to healthcare informatics, education and cost reduction.

Effect of L-tryptophan feeding on brain mitochondrial ion transport in net- confined climbing perch (Anabas testudineus Bloch)

Serotonin (5-HT), a neurohormone with many physiological actions, is synthesized from the dietary essential amino acid tryptophan (TRP). However, the effects of TRP on neuronal ion transporters and its role in stress response have not yet been identified in the teleost fish. The effects of varied doses of TRP on the activities of mitochondrial (m) and cytosolic (c) ion transporters were examined in the forebrain (FB), midbrain (MB) and hindbrain (HB) segments of an air-breathing fish Anabas testudineus Bloch kept either in non-stressed or in stressed condition. Feeding the fish with varied doses of TRP (1, 2 and 4 mg g -1 feed) for seven days produced dose-dependent effects on Na + , K + -ATPase and H + -ATPase activities in different regions of fish brain. A decrease in (P<0.001) Na + , K + -ATPase activity was found in FB and MB after seven days of TRP treatment. TRP decreased (P<0.001) H + -ATPase activity in the FB but increased Na + , K + ATPase activity in all the three regions of the brain. In non-stressed fish, feeding 20 mg g -1 TRP for two days produced a substantial rise (P<0.001) in cH + -ATPase activity in the FB and HB of the fish. But mH + -ATPase showed a reversed response to TRP feeding. On the contrary, TRP treatment in net-confined fish showed a decrease (P<0.001) in the cH + -ATPase activity in the FB and HB, whereas it produced an increase (P<0.001) in the MB. In non-stressed fish, cytosolic and mitochondrial Ca 2+ -ATPase activities in FB and MB decreased (P<0.001) after TRP feeding. Feeding TRP in stressed fish reduced (P<0.001) cCa 2+ - ATPase activity in the MB but produced an increase (P<0.001) in its activity in mitochondria. In non-stressed fish, TRP feeding decreased (P<0.001) mMg 2+ -ATPase activity in the FB and MB segments. TRP treatment, in stressed fish, however decreased (P<0.001) Mg 2+ -ATPase activity in the MB but not in other brain segments. The data indicate that TRP can regulate brain mitochondrial ion transport, and induction of stress may modify the TRP-induced mitochondrial ion transport response of air-breathing fish.

Extreme Learning Machine-Based Classification of ADHD Using Brain Structural MRI Data

BackgroundEffective and accurate diagnosis of attention-deficit/hyperactivity disorder (ADHD) is currently of significant interest. ADHD has been associated with multiple cortical features from structural MRI data. However, most existing learning algorithms for ADHD identification contain obvious defects, such as time-consuming training, parameters selection, etc. The aims of this study were as follows: (1) Propose an ADHD classification model using the extreme learning machine (ELM) algorithm for automatic, efficient and objective clinical ADHD diagnosis. (2) Assess the computational efficiency and the effect of sample size on both ELM and support vector machine (SVM) methods and analyze which brain segments are involved in ADHD.MethodsHigh-resolution three-dimensional MR images were acquired from 55 ADHD subjects and 55 healthy controls. Multiple brain measures (cortical thickness, etc.) were calculated using a fully automated procedure in the FreeSurfer software package. In total, 340 cortical features were automatically extracted from 68 brain segments with 5 basic cortical features. F-score and SFS methods were adopted to select the optimal features for ADHD classification. Both ELM and SVM were evaluated for classification accuracy using leave-one-out cross-validation.ResultsWe achieved ADHD prediction accuracies of 90.18% for ELM using eleven combined features, 84.73% for SVM-Linear and 86.55% for SVM-RBF. Our results show that ELM has better computational efficiency and is more robust as sample size changes than is SVM for ADHD classification. The most pronounced differences between ADHD and healthy subjects were observed in the frontal lobe, temporal lobe, occipital lobe and insular.ConclusionOur ELM-based algorithm for ADHD diagnosis performs considerably better than the traditional SVM algorithm. This result suggests that ELM may be used for the clinical diagnosis of ADHD and the investigation of different brain diseases.

Vertebrate Intersectin1 Is Repurposed to Facilitate Cortical Midline Connectivity and Higher Order Cognition

Invertebrate studies have highlighted a role for EH and SH3 domain Intersectin (Itsn) proteins in synaptic vesicle recycling and morphology. Mammals have two Itsn genes (Itsn1 and Itsn2), both of which can undergo alternative splicing to include DBL/PH and C2 domains not present in invertebrate Itsn proteins. To probe for specific and redundant functions of vertebrate Itsn genes, we generated Itsn1, Itsn2, and double mutant mice. While invertebrate mutants showed severe synaptic abnormalities, basal synaptic transmission and plasticity were unaffected at Schaffer CA1 synapses in mutant mice. Surprisingly, intercortical tracts-corpus callosum, ventral hippocampal, and anterior commissures-failed to cross the midline in mice lacking Itsn1, but not Itsn2. In contrast, tracts extending within hemispheres and those that decussate to more caudal brain segments appeared normal. Itsn1 mutant mice showed severe deficits in Morris water maze and contextual fear memory tasks, whereas mice lacking Itsn2 showed normal learning and memory. Thus, coincident with the acquisition of additional signaling domains, vertebrate Itsn1 has been functionally repurposed to also facilitate interhemispheric connectivity essential for high order cognitive functions.

Abstract 171: CRP, IL-18, and BNP are Associated with Regional Brain Atrophy: Results from the Dallas Heart Study

Purpose: Multiple biomarkers have been associated with total brain atrophy. However, little is known about their relationship to segmental atrophy in a large, multi-ethnic, population-based sample. Materials and Methods: 3D-MPRAGE brain images obtained at 3T from 2082 participants of the Dallas Heart Study (DHS) 2 were analyzed with Freesurfer and outlier analysis was performed. Divisive eigenvalue clustering of 89 brain segments yielded 24 groups with linked atrophy patterns. Plasma C-reactive protein (CRP), IL-18, homocsysteine and B-type natriuretic peptide (BNP) obtained 7 years prior during DHS 1 were available for 1343, 840, 1333 and 1331 participants, respectively. Multivariate linear regression analysis with adjustments for age, ethnicity, and gender were used to demonstrate associations between biomarkers and atrophy clusters. Results: Nine atrophy clusters were associated with CRP, three atrophy clusters were associated with IL-18, and six atrophy clusters were associated with BNP (Table 1). Homocysteine did not have any significant correlations. Conclusions: The markers studied had associations with distinct patterns of segmental atrophy indicating they may have unique interactions in different brain regions. This suggests that distinct inflammatory and other pathways may be at work in specific regions of the brain and that their localized effects may be obscured by approaches evaluating solely total brain volumes. Table 1:

Mesencephalic neuronal populations: new insights on the ventral differentiation programs.

The midbrain is a complex structure where different functions are located. This formation is mainly involved in the visual and auditory information process (tectum) and visual movements and motor coordination (tegmentum). Here we display a complete description of midbrain anatomy based on the prosomeric model and of the developmental events that take place to generate this structure. We also summarize the new data about the differentiation and specification of the basal populations of the midbrain. The neural tube suffers the influence of several secondary organizers. These signaling centers confer exact positional information to the neuroblasts. In the midbrain these centers are the Isthmic organizer for the antero-posterior axis and the floor and roof plates for the dorso-ventral axis. This segment of the brain contains, in the dorsal part, structures such as the collicula (superior and inferior), tectal grey and the preisthmic segment, and in the basal plate, neuronal populations such as the oculomotor complex, the dopaminergic substantia nigra and the ventral tegmental area, the reticular formation and the periacueductal grey. Knowledge of the genetic cascades involved in the differentiation programs of the diverse populations will be extremely important to understand not only how the midbrain develops, but how degenerative pathologies, such as Parkinson's disease, occurs. These cascades are triggered by signaling molecules such as Shh, Fgf8 or Wnt1 and are integrated by receptor complexes and transcription factors. These are directly responsible for the induction or repression of the differentiation programs that will produce a specific neuronal phenotype.

Letter to the Editor regarding “Quantification of Paraquat, MPTP, and MPP+ in brain tissue using microwave-assisted solvent extraction (MASE) and high-performance liquid chromatography–mass spectrometry”

In 2009, a paper was published in this journal describing new methods for extraction and analysis of paraquat, MPTP, and MPP+ using microwave extraction and LC/ MS/MS quantitation [1]. These compounds are important in mouse models of Parkinson's disease. One of the paper's co-authors, Mona Thiruchelvam, was recently admonished for scientific misconduct [2] and had to withdraw two of her dozen or so papers on the behavior of treated mice because she reused image data on brain segments. Under normal circumstances, I would not draw attention to her role on the aforementioned paper published here but individuals who are more concerned with personal attack than scientific integrity are using Dr. Thiruchelvam's role on the paper published here to try and besmirch the reputation of other co-authors. As the corresponding author of the ABC paper, I felt it necessary to set the record straight. Dr. Thiruchelvam provided samples and a write-up of how the samples were created (type of animal, dosing, etc.) and nothing more. She had no role in the analysis method, either here or at CDC and her limited participation does not affect the quality of the work published here. As analysts, we are often the target of those who have an agenda because we are the messengers of bad news for someone, either those hoping we will find something in a sample or those hoping we do not. Our principal role is to make the measurement and to the best of our ability provide information about its precision and accuracy. We will never know the outcome of Dr. Thiruchelvam's studies that were withdrawn, but they had nothing to do with the work presented here. Anyone who would imply that her participation in this work impugns the integrity of the other investigators clearly has a secondary agenda. I am disappointed that this letter had to be written, but I am thankful to have the opportunity to explain the situation in greater detail. As analysts, we provide the data and I encourage all to remember that whether the information is good or bad, from your viewpoint, don't kill the messenger.

Long-term outcome for endoscopic third ventriculostomy alone or in combination with choroid plexus cauterization for congenital aqueductal stenosis in African infants

The authors have previously reported on the overall improved efficacy of endoscopic third ventriculostomy (ETV) combined with choroid plexus cauterization (CPC) for infants younger than 1 year of age. In the present study they specifically examined the long-term efficacy of ETV with or without CPC in 35 infants with congenital aqueduct stenosis treated at CURE Children's Hospital of Uganda during the years 2001-2006. Infants with congenital aqueductal stenosis were treated during 2 distinct treatment epochs: all underwent ETV alone, and subsequently all underwent ETV-CPC. Prospectively collected data in the clinical database were reviewed for all infants with an age < 1 year who had been treated for hydrocephalus due to congenital aqueductal stenosis. Study exclusion criteria included: 1) a history or findings on imaging or at the time of ventriculoscopy that suggested a possible infectious cause of the hydrocephalus, including scarred choroid plexus; 2) an open aqueduct or an aqueduct obstructed by a membrane or cyst rather than by stenosis; 3) severe malformations of the cerebral hemispheres including hydranencephaly, significant segments of undeveloped brain, or schizencephaly; 4) myelomeningocele, encephalocele, Dandy-Walker complex, or tumor; or 5) previous shunt insertion. The time to treatment failure was analyzed using the Kaplan-Meier method to construct survival curves. Log-rank (Mantel-Cox) and Gehan-Breslow-Wilcoxon tests were used to determine whether differences between the 2 treatment groups were significant. Thirty-five patients met the study criteria. Endoscopic third ventriculostomy alone was performed in 12 patients (mean age 4.7 months), and combined ETV-CPC was performed in 23 patients (mean age 3.5 months). For patients without treatment failure, the mean and median follow-ups were, respectively, 51.6 and 48.0 months in the ETV group and 31.2 and 26.4 months in the ETV-CPC group. Treatment was successful in 48.6% of the patients who underwent ETV alone, as accurately predicted by the Endoscopic Third Ventriculostomy Success Score (ETVSS), and in 81.9% of the patients who underwent ETV-CPC (p = 0.0119, log-rank test; p = 0.0041, Gehan-Breslow-Wilcoxon test; HR 6.42 [95% CI 1.51-27.36]). Combined ETV-CPC is significantly superior to ETV alone for infants younger than 1 year of age with congenital aqueductal stenosis. The fact that the outcome for ETV alone was accurately predicted by the ETVSS suggests that these results are applicable in developed countries.

Analysis of Neural Crest Migration and Differentiation by Cross-species Transplantation

Avian embryos provide a unique platform for studying many vertebrate developmental processes, due to the easy access of the embryos within the egg. Chimeric avian embryos, in which quail donor tissue is transplanted into a chick embryo in ovo, combine the power of indelible genetic labeling of cell populations with the ease of manipulation presented by the avian embryo. Quail-chick chimeras are a classical tool for tracing migratory neural crest cells (NCCs). NCCs are a transient migratory population of cells in the embryo, which originate in the dorsal region of the developing neural tube. They undergo an epithelial to mesenchymal transition and subsequently migrate to other regions of the embryo, where they differentiate into various cell types including cartilage, melanocytes, neurons and glia. NCCs are multipotent, and their ultimate fate is influenced by 1) the region of the neural tube in which they originate along the rostro-caudal axis of the embryo, 2) signals from neighboring cells as they migrate, and 3) the microenvironment of their ultimate destination within the embryo. Tracing these cells from their point of origin at the neural tube, to their final position and fate within the embryo, provides important insight into the developmental processes that regulate patterning and organogenesis. Transplantation of complementary regions of donor neural tube (homotopic grafting) or different regions of donor neural tube (heterotopic grafting) can reveal differences in pre-specification of NCCs along the rostro-caudal axis. This technique can be further adapted to transplant a unilateral compartment of the neural tube, such that one side is derived from donor tissue, and the contralateral side remains unperturbed in the host embryo, yielding an internal control within the same sample. It can also be adapted for transplantation of brain segments in later embryos, after HH10, when the anterior neural tube has closed. Here we report techniques for generating quail-chick chimeras via neural tube transplantation, which allow for tracing of migratory NCCs derived from a discrete segment of the neural tube. Species-specific labeling of the donor-derived cells with the quail-specific QCPN antibody allows the researcher to distinguish donor and host cells at the experimental end point. This technique is straightforward, inexpensive, and has many applications, including fate-mapping, cell lineage tracing, and identifying pre-patterning events along the rostro-caudal axis. Because of the ease of access to the avian embryo, the quail-chick graft technique may be combined with other manipulations, including but not limited to lens ablation, injection of inhibitory molecules, or genetic manipulation via electroporation of expression plasmids, to identify the response of particular migratory streams of NCCs to perturbations in the embryo's developmental program. Furthermore, this grafting technique may also be used to generate other interspecific chimeric embryos such as quail-duck chimeras to study NCC contribution to craniofacial morphogenesis, or mouse-chick chimeras to combine the power of mouse genetics with the ease of manipulation of the avian embryo.

Are mushroom bodies cerebellum-like structures?

The mushroom bodies are distinctive neuropils in the protocerebral brain segments of many protostomes. A defining feature of mushroom bodies is their intrinsic neurons, masses of cytoplasm-poor globuli cells that form a system of lobes with their densely-packed, parallel-projecting axon-like processes. In insects, the role of the mushroom bodies in olfactory processing and associative learning and memory has been studied in depth, but several lines of evidence suggest that the function of these higher brain centers cannot be restricted to these roles. The present account considers whether insight into an underlying function of mushroom bodies may be provided by cerebellum-like structures in vertebrates, which are similarly defined by the presence of masses of tiny granule cells that emit thin parallel fibers forming a dense molecular layer. In vertebrates, the shared neuroarchitecture of cerebellum-like structures has been suggested to underlie a common functional role as adaptive filters for the removal of predictable sensory elements, such as those arising from reafference, from the total sensory input. Cerebellum-like structures include the vertebrate cerebellum, the electrosensory lateral line lobe, dorsal and medial octavolateral nuclei of fish, and the dorsal cochlear nucleus of mammals. The many architectural and physiological features that the insect mushroom bodies share with cerebellum-like structures suggest that it might be fruitful to consider mushroom body function in light of a possible role as adaptive sensory filters. The present account thus presents a detailed comparison of the insect mushroom bodies with vertebrate cerebellum-like structures.

Advantages of Extended Brain Perfusion Computed Tomography

Recent technical developments have led to an extension of perfusion computed tomography (PCT) scan range to cover nearly the entire brain and to reconstruct time resolved (4d) CT-angiography (CTA) datasets from the PCT data. The purpose of this study was to compare the results of simulated standard PCT and extended PCT with 4d-CTA. Extended multimodal stroke CT (unenhanced cranial CT, CTA, and PCT) was acquired in 72 patients. PCT images with a scan coverage of 9.6 cm in the z-axis, simulated 2 cm PCT images at the level of the basal ganglia comparable to standard PCT, standard supra-aortic CTA, and 4d-CTA images were reconstructed. Two readers assessed the PCT image quality as well as pathologic findings in extended and simulated PCT, CTA, and 4d-CTA. The brain was divided into 4 axial segments. The independent samples t test was applied to test differences between data for significance. In 75.0% of all patient exams, pathologic findings were observed in the PCT; these were located in 138 brain segments. In 24.1% of all 54 exams with pathologic PCT findings, the pathology would have been missed on standard PCT. The longer scan coverage resulted in a different final diagnosis in 34.7% of all exams. Quality of the PCT parameter maps was on average very good both for the supratentoric and the infratentoric brain areas (4.28 and 4.18, respectively, on a 5-point scale). In 90% of all exams with pathologic changes in the CTA, these abnormalities were also noted on 4d-CTA. In only 2.8% of all cases, the additional time resolution of the 4d-CTA provided additional information. Extending the scan coverage of PCT from 2 cm to 9.6 cm led to an augmentation of clinically important information in the imaging of acute stroke.

Segment-Specific Neuronal Subtype Specification by the Integration of Anteroposterior and Temporal Cues

Author SummaryAn animal's nervous system contains a wide variety of neuronal subtypes generated from neural progenitor (“stem”) cells, which generate different types of neurons at different axial positions and time points. Hence, the generation and specification of unique neuronal subtypes is dependent upon the integration of both spatial and temporal cues within distinct stem cells. The nature of this integration is poorly understood. We have addressed this issue in the Drosophila neuroblast 5–6 lineage. This stem cell is generated in all 18 segments of the central nervous system, stretching from the brain down to the abdomen of the fly, but a larger lineage containing a well-defined set of cells—the Apterous (Ap) cluster—is generated only in thoracic segments. We show that segment-specific generation of the Ap cluster neurons is achieved by the integration of the anteroposterior and temporal cues in several different ways. Generation of the Ap neurons in abdominal segments is prevented by anteroposterior cues stopping the cell cycle in the stem cell at an early stage. In brain segments, late-born neurons are generated, but are differently specified due to the presence of different anteroposterior and temporal cues. Finally, in thoracic segments, the temporal and spatial cues integrate on a highly limited set of target genes to specify the Ap cluster neurons.

Right Time, Right Place: The Four-Dimensional Pattern of Fly Neuron Development

​EmbryonicEmbryonic development is a four-dimensional process: in order to create an organism, the right genes must be expressed at the right time and in the right place. But while the overall strategy of embryogenesis is clear—successive waves of gene expression give rise to a pattern of transcription factors varying in time and space, driving cell differentiation—relatively little is known about the four-dimensional details of this process for most cell types. In a new study in this issue of PLoS Biology, Daniel Karlsson, Magnus Baumgardt, and Stefan Thor elucidate some of those details in the developing nervous system of the fly and show that major differences between body regions can arise from simple changes in gene expression. The nervous system of the fly develops from neuroblasts arranged into segments along the larval body (shown with a green fluorescent marker). In the fly, the nervous system develops from progenitor cells called neuroblasts, arranged into 18 segments that are lined up down the length of the larval body. In the thoracic segments, located about a third of the way down from the head, certain neuroblasts generate four neurons called the Ap (for “apterous”) cluster, distinguished from other neurons by the expression of a specific set of transcription factors. Surprisingly, equivalent neuroblasts are present not only in thoracic segments but also in abdominal and brain segments. So, why are Ap cluster neurons formed only in thoracic segments? In previous work, the authors showed that Ap cluster neurons form at the end of a long series of neuroblast cell divisions and only in the presence of specific molecular signals. Here, they found that neuroblast cells in the abdomen stopped dividing before reaching the stage that would create Ap clusters. A group of powerful pattern-generating genes called the bithorax complex, which is able to turn cell division off, is expressed at the proper time in the abdomen, and so, the authors tested its role in terminating abdominal neuroblast division. They found that switching the complex off by mutation allowed cell division to proceed, and Ap clusters to form, in abdominal segments. Another key player in preventing Ap cluster formation in the abdomen was the gene castor. castor is one of a sequence of “time window” genes that turn on and then off during development. Some events, including Ap cluster formation, are possible only when the Castor window “opens,” which occurs later in development, after abdominal neuroblasts have already stopped dividing. In the thorax, the bithorax complex is inactive. But several other genes appeared to play critical roles. One, called homothorax, was present in high concentrations in thoracic segments, and its mutation prevented Ap cluster formation, suggesting its presence was critical for forming Ap clusters. With the Castor window open, homothorax could promote expression of another gene, collier, which triggers expression of the markers that define Ap cluster neurons. Two other genes, including Antennapedia, were also needed to get full collier expression. In the most anterior segments, which make up the fly brain, neuroblast division continued long enough to make Ap clusters, but nonetheless the clusters didn't form. The reason, the authors found, was that these segments lacked Antennapedia, as well as another critical time-window gene acting in the thorax, called grainyhead. When they induced brain segments to express both Antennapedia and grainyhead, the segments developed Ap clusters, just like thoracic segments did. When they simultaneously expressed these genes and blocked the bithorax complex, almost every segment, from abdomen to brain, developed Ap clusters as if they were all thoracic segments. While the details are complicated, the underlying logic that emerges from this study is unexpectedly simple. The thoracic segment development pathway can be considered the default pattern, and the two regions that are “not thorax”—abdomen and brain—employ two entirely distinc strategies for becoming different. In the abdomen, progenitor cells are turned off early, whereas in the brain, specific promoting factors are withheld. These results are likely to lead to further insights into general patterns of fly development and, since many of these genes are shared by vertebrates, will likely be more widely applicable as well. Karlsson D, Baumgardt M, Thor S (2010) Segment-Specific Neuronal Sub-Type Specification by the Integration of Anteroposterior and Temporal Cues. doi:10.1371/journal.pbio.1000368

The Gospel of John and the Five Senses

(ProQuest: ... denotes non-US-ASCII text omitted.) The Gospel of John uses a number of images express its understanding of what it means believe in Jesus and belong community of faith. These images, drawn from material world, are used as symbols or vehicles of divine world.1 Indeed, faith cannot appear and develop without such imagery, so foundational is it world of fourth evangelist. Of particular significance is remarkably cohesive presence of images relating five senses throughout Johannine narrative-sight, hearing, taste, touch, and smell-a narrative presence that is grounded in John's central theological motif, incarnation. While some of senses have been recognized and discussed extensively, others have been paid scant attention; nor has cooperation of all five senses together been sufficiently observed.2 In physiognomic terms, five senses-the number and identification of which are generally attributed Aristotle-are means by which human beings apprehend external reality. Each is associated with one organ or aspect of body, and each corresponds a particular segment of brain.3 Sight, or vision, asso- ciated with eyes and physiological intake of light through cornea and pupil, enables us discern color, movement, shape, distance, and size. Hearing, or audition, involves movement of sound through ears eardrum, which sends messages brain, telling it of volume, type, intensity, and balance. Taste, or gustation, occurs on tongue with its manifold taste buds, detecting sweet and sour, salty and bitter, and conveying appropriate messages brain. Touch, or somatic feeling, takes place on skin of body, in middle layer that has nerve endings connected brain, discerning whether touch is soft or hard, gentle or sharp, safe or dangerous, painful or painless, pleasant or unpleasant. Finally, smell, or olfaction, employs air and breath through nose and nerves in top of nasal cavity transmit messages of pleasant or unpleasant, threatening or soothing, as well as summon memory. Each of these senses may be lacking in any person, and each, therefore, has its opposite (respectively, blindness, deafness, ageusia, anesthesia, and anosmia). Each, too, works together with others-for example, taste and smell combine discern flavor. Generally, senses of sight, hearing, and smell involve no necessary contact, unlike taste and touch which do; yet taken together, five senses enable us see world in a unified way.4 The senses, in short, are intrinsic what makes us human: means of our apprehension and communication, and basis of our experience.5 Their capacity for metaphorical or spiritual signification is also important,which is evident in way Aristotle sees senses as part of soul; later Jewish-Arabic philosophy in Middle Ages made an important distinction between external and internal senses.6 In this article I examine way in which Fourth Gospel employs each of five senses as a core image in narrative for life of faith. I describe briefly occurrence and usage of senses in Johannine text in order of frequency and intensity of usage in Gospel narrative. I look also at implications of five senses, both separately and together, for implied reader's imaginative entry into symbolic universe of Fourth Gospel, since that is only way, in this text, comprehend and apprehend Johannine faith. I. Sight The sense of sight has been described as mankind's most noble and dependable sense.7 In ancient world, likewise, dominance of vision among senses is widely recognized: the eyes are most important marker of character and are frequently used in this way.8 It is not surprising, therefore, that most significant Johannine image based on senses is that of sight, mostly found in verbal form to see. …

Function Recovery after Transplantation of Fetal Brain Tissue into Injured Spinal Cord in Experimental Rats

Rakei, S.M., Rahmanian, A., Saffarian, A., Shafeian, R. and Mehrabani, D. 2009. Function recovery after transplantation of fetal brain tissue into injured spinal cord in experimental rats. J. Appl. Anim. Res., 36: 303–306. To determine the effect of transplantation of fetal brain tissue on regeneration of injured spinal cord and the limb function recovery, forty 30-week old male Sprague-Dawley 350–450 g rats were randomly and equally divided into two groups. In 5 pregnant rats the fetuses were removed and the embryonic brain tissues were sectioned into 0.05 mm segments under microscope. The vertebral column was exposed and a 0.1 mm segment of spinal cord medulla at the T10-T11 level was completely dissected in all rats of both groups. A 0.05 mm segment of rat fetus brain was implanted into the injured section of spinal cord of all rats in the case group. No further intervention was done in the control group. After 24 h lower extremity paraplegia was confirmed in all rats. After six weeks, no locomotor improvement was seen in the control group (Basso-Beattie-Bresnahan locomotor rating scale, BBB=0). 15% of rats in the case group had some degrees of recovery from spinal cord injury. Our findings suggest that fetal neural transplants could potentially be an effective surgical intervention for treatment of SCI even though more investigations are warranted.

The involvement of engrailed and wingless during segmentation in the onychophoran Euperipatoides kanangrensis (Peripatopsidae: Onychophora) (Reid 1996)

As the putative sister group to the arthropods, onychophorans can provide insight into ancestral developmental mechanisms in the panarthropod clade. Here, we examine the expression during segmentation of orthologues of wingless (Wnt1) and engrailed, two genes that play a key role in defining segment boundaries in Drosophila and that appear to play a role in segmentation in many other arthropods. Both are expressed in segmentally reiterated stripes in all forming segments except the first (brain) segment, which only shows an engrailed stripe. Engrailed is expressed before segments are morphologically visible and is expressed in both mesoderm and ectoderm. Segmental wingless expression is not detectable until after mesodermal somites are clearly distinct. Early engrailed expression lies in and extends to both sides of the furrow that first demarcates segments in the ectoderm, but is largely restricted to the posterior part of somites. Wingless expression lies immediately anterior to engrailed expression, as it does in many arthropods, but there is no precise cellular boundary between the two expression domains analogous to the overt parasegment boundary seen in Drosophila. Engrailed stripes extend along the posterior part of each limb bud, including the antenna, while wingless is restricted to the distal tip of the limbs and the neurectoderm basal to the limbs.

Three-dimensional stereotactic ROI template for measuring regional cerebral blood flow in 99mTc-ECD SPECT: comparison with the manual tracing method

The three-dimensional stereotactic region of interest template (3DSRT) is computer software, which enables the automatic measurement of regional cerebral blood flow (rCBF). This study was undertaken to compare the rCBF values obtained using the 3DSRT method and the conventional manual tracing method. Twelve patients with normal brains who underwent technetium-99m L,L-ethyl cysteinate dimer single-photon emission computed tomography studies were enrolled in this study. The brains were divided into 12 segments in each hemisphere, and rCBF was measured in each segment. The regions of interest were automatically placed in the segments in the 3DSRT method and were manually traced by five nuclear medicine technicians in the manual tracing method. The rCBF values obtained were compared between the two methods. Interoperator reliability was evaluated in the manual tracing method. The rCBF values were significantly higher in the manual tracing method than in the 3DSRT method in all segments except for the angular segment. A good correlation was seen between the two methods in the rCBF values in 10 (83.3%) of the 12 brain segments (range of coefficient of determinations: 0.73-0.94). A poor correlation, however, was seen in the pericallosal (0.50) and hippocampal (0.53) segments. Interoperator reliability was lower in these two segments than in the other segments in the manual tracing method. Although the rCBF values obtained using the manual tracing method and the 3DSRT method show good correlation in most segments, care is required when comparing the results for the pericallosal and hippocampal segments.