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Voxel-based morphometry of comorbid schizophrenia and learning disability: analyses in normalized and native spaces using parametric and nonparametric statistical methods.

We employed voxel-based morphometry (VBM) to compare the distributions of grey matter found in structural magnetic resonance imaging (MRI) brain scans of patients with comorbid learning disability with schizophrenia, schizophrenia alone, learning disability alone, and normal controls. Our primary aim was to replicate a previous region of interest (ROI) finding that comorbids and schizophrenics belong to the same population. Nonparametric analysis in normalized space showed no significant differences in grey matter distribution between the comorbid and schizophrenia groups. Furthermore, this analysis showed significant grey matter reductions in the comorbid and schizophrenia groups when compared to the learning-disabled or the normal controls. Parametric analysis localized the significant grey matter reductions between the normal controls and the comorbid and schizophrenia groups to the prefrontal and temporal lobes. It also identified an area of increased grey matter, on the inferior aspect of the postcentral gyrus, in the learning-disabled alone compared to the other groups. Native space parametric and nonparametric analyses, based on modulation of the normalized scans, confirmed the similarity in grey matter distribution of the comorbid and schizophrenia groups. Results confirm the ROI finding that in native space the learning-disabled group possesses the least and normal controls the most grey matter for the cohort. An increase in the basal ganglia of patients with schizophrenia vs. the learning-disabled, probably attributable to antipsychotic medication, was identified in the native space analysis. The native space results did not however register statistically significant temporal lobe reductions found under normalized analysis between schizophrenics and normal controls. This may be attributable to minor physical anomalies (MPA) in the schizophrenic cranium. Overall, these VBM results replicate previous ROI findings and are compatible with the view that comorbid learning disability with schizophrenia is a severe form of schizophrenia, rather than a consequence of learning disability. VBM has the facility to compare grey matter distributions in this structurally diverse cohort.

Adult↗

Labeled albumin in plasma and removal paths from pleural space in control and increased ventilation.

Increased ventilation was shown to markedly increase lymphatic drainage and plasma content of labeled proteins injected into pleural space relative to control ventilation. These proteins reach plasma by lymphatic drainage: directly through parietal pleura stomata, and indirectly from pleural interstitium, reached by diffusion, convection and transcytosis. Increased drainage from interstitium should not involve a comparable increase in protein removal from pleural space by these transports, while increased drainage through stomata involves a comparable increase in protein removal. Hence, relative increase in labeled protein removal from pleural space caused by increased ventilation should be marked only if drainage through stomata contributed most of this removal, whereas relative increase of labeled proteins in plasma should be marked in either case. We injected 3 ml of albumin-Ringer with albumin-Texas red into the pleural space of three groups of anesthetized rabbits: control, CO2-, or muscle stimulation-increased ventilation. Increased ventilation for 3 h (78 and 61%, respectively) increased (P < 0.01) labeled albumin in plasma by 132 and 106%, respectively, but did not significantly increase its removal. Hence, lymphatic drainage through stomata should not contribute most of liquid and protein removal from pleural space.

Animals↗

Effect of 12-hour road transportation on physiological, immunological and haematological parameters in bulls housed at different space allowances.

The effects of transporting Holstein Friesian bulls (n=72; bodyweight 403+/-3.5 kg) for 12h by road were examined. Adrenal, haematological and immune responses, body temperature and performance were recorded. The animals had been previously housed for 96 days at three space allowances (1.2, 2.7 or 4.2m(2) per bull). The bulls were allocated to one of two treatments: T (transport for 12h; n=16 per space allowance) and C (control; n=8 per space allowance). Basal cortisol plasma concentrations and interferon (IFN)-gamma production from cultured lymphocytes did not show any statistically significant difference (P>0.05) following the housing period. Removing bulls from their home pens and walking them to the pre-loading crush facility, loading onto the transporter, and unloading following the 12h road journey, significantly (P<0.001) increased plasma cortisol concentration. The bulls housed at 4.2m(2) had greater (P<0.05) plasma cortisol concentrations than bulls housed at 1.2m(2) at loading, unloading, or on return to the crush holding facility; those housed at 1.2m(2) had greater (P<0.05) plasma cortisol concentrations than bulls housed at 2.7 and 4.2m(2) in their home pens after transport. There was an increased (P<0.05) plasma cortisol response in the T than in the C bulls following adrenocorticotrophic hormone administration. Transport significantly reduced (P<0.05) IFN-gamma production, lymphocyte % and body weight and significantly increased (P<0.05) neutrophils, eosinophils, packed cell volume, red blood cell numbers and haemoglobin. In conclusion, housing bulls for 96 days in a range of space allowances did not affect basal cortisol response or immune function parameters. Whereas transport increased plasma cortisol and reduced the immune response in the short-term, the changes were transient and within normal physiological ranges, suggesting that 12h road transport had no adverse effect on welfare status over the longer term. Furthermore, transport of bulls housed at increased space allowance (4.2m(2)/bull) resulted in a greater plasma cortisol response, albeit still within normal physiological range.

Animal Husbandry↗

Twelve weeks of nightly stretch does not reduce thumb web-space contractures in people with a neurological condition: a randomised controlled trial.

QUESTION: What is the effectiveness of 12 weeks of nightly stretch in reducing thumb web-space contracture in people with neurological conditions? DESIGN: Assessor-blinded, randomised controlled trial. PARTICIPANTS: Forty-four (one dropout)community-dwelling patients with a neurological condition (14 stroke, 7 traumatic brain injury, 23 spinal cord injury) who had uni or bilateral thumb web-space contractures (60 thumbs). INTERVENTION: The experimental thumbs were splinted into a stretched,abducted position each night for 12 weeks. The control thumbs were not splinted. OUTCOME MEASURES: Thumb web-space was measured as the carpometacarpal angle during the application of a 0.9 Nm abduction torque before and after intervention. RESULTS: The mean increase in thumb web-space after 12 weeks was 1 deg (95% CI, -1 to 2). CONCLUSION: Intensive stretch administered regularly over three months does not reduce thumb web-space contractures in neurological conditions.

Adult↗

The convex basis of the left null space of the stoichiometric matrix leads to the definition of metabolically meaningful pools.

The stoichiometric matrix, S, represents a mapping of reaction rate vectors into a space of concentration time derivatives. The left null space of the stoichiometric matrix contains the dynamic invariants: a combination of concentration variables, referred to as metabolic pools, whose total concentration does not change over time. By analogy to the traditional reaction map formed by S, a compound map can be derived from -S(T). The analogy to flux analysis of the (right) null space of S enables us to classify the metabolic pools into three categories: Type A that contains chemical elements and their combinations in the form of certain moieties, Type B that contains such moieties in addition to cofactors carrying such moieties that are internal to the network, and Type C that contains only the cofactors. A convex formulation of the basis for the left null space allows us to directly classify the metabolic pools into these three categories. Type B metabolic pools include conservation pools that form conjugates of moiety-occupied and moiety-vacant concentration states of metabolites and cofactors. Type B metabolic pools thus describe the various states of moiety exchange between the primary substrates and the cofactors that capture properties like energy and redox potential. The convex basis gives clear insight into this exchange for glycolytic pathway in human red blood cell, including the identification of high and low energy pools that form conjugates. Examples suggest that pool maps may be more appropriate for signaling pathways than flux maps. The analysis of the left null space of the stoichiometric matrix allows us to define the achievable states of the cell and their physiological relevance.

Algorithms↗

Fluid bilayer structure determination by the combined use of x-ray and neutron diffraction. II. "Composition-space" refinement method.

This is the second of two papers describing a method for the joint refinement of the structure of fluid bilayers using x-ray and neutron diffraction data. We showed in the first paper (Wiener, M. C., and S. H. White. 1990. Biophys. J. 59:162-173) that fluid bilayers generally consist of a nearly perfect lattice of thermally disordered unit cells and that the canonical resolution d/hmax is a measure of the widths of quasimolecular components represented by simple Gaussian functions. The thermal disorder makes possible a "composition space" representation in which the quasimolecular Gaussian distributions describe the number or probability of occupancy per unit length across the width of the bilayer of each component. This representation permits the joint refinement of neutron and x-ray lamellar diffraction data by means of a single quasimolecular structure that is fit simultaneously to both diffraction data sets. Scaling of each component by the appropriate neutron or x-ray scattering length maps the composition space profile to the appropriate scattering length space for comparison to experimental data. Other extensive properties, such as mass, can also be obtained by an appropriate scaling of the refined composition space structure. Based upon simple bilayer models involving crystal and liquid crystal structural information, we estimate that a fluid bilayer with hmax observed diffraction orders will be accurately represented by a structure with approximately hmax quasimolecular components. Strategies for assignment of quasimolecular components are demonstrated through detailed parsing of a phospholipid molecule based upon the one-dimensional projection of the crystal structure of dimyristoylphosphatidylcholine. Finally, we discuss in detail the number of experimental variables required for the composition space joint refinement. We find fluid bilayer structures to be marginally determined by the experimental data. The analysis of errors, which takes on particular importance under these circumstances, is also discussed.

Lipid Bilayers↗

Lattice spacing changes accompanying isometric tension development in intact single muscle fibers.

The myosin lattice spacing of single intact muscle fibers of the frog, Rana temporaria, was studied in Ringer's solution (standard osmolarity 230 mOsm) and hyper- and hypotonic salines (1.4 and 0.8 times standard osmolarity respectively) in the relaxed state, during "fixed end" tetani, and during shortening, using synchrotron radiation. At standard tonicity, a tetanus was associated with an initial brief lattice expansion (and a small amount of sarcomere shortening), followed by a slow compression (unaccompanied by sarcomere length changes). In hypertonic saline (myosin lattice compressed by 8.1%), these spacing changes were suppressed, in hypotonic saline (lattice spacing increased by 7.5%), they were enhanced. During unloaded shortening of activated fibers, a rapid lattice expansion occurred at all tonicities, but became larger as tonicity was reduced. This expansion was caused in part by the change in length of the preparation, but also by a recoil of a stressed radial compliance associated with axial force. The lattice spacing during unloaded shortening was equal to or occasionally greater than predicted for a relaxed fiber at that sarcomere length, indicating that the lattice compression associated with activation is rapidly reversed upon loss of axial force. Lattice recompression occurred upon termination of shortening under standard and hypotonic conditions, but was almost absent under hypertonic conditions. These observations indicate that axial cross-bridge tension is associated with a compressive radial force in intact muscle fibers at full overlap; however, this radial force exhibits a much greater sensitivity to lattice spacing than does the axial force.

Animals↗

Serial changes of cystic air spaces in fibrosing alveolitis: a CT-pathological study.

In patients with cryptogenic fibrosing alveolitis (CFA), subpleural large cysts are sometimes seen within honeycombing on computed tomography (CT). These cysts may be interpreted as bullae and the coexistence of emphysema with CFA might be assumed. We evaluated whether cystic spaces in honeycombing become larger in patients with CFA on serial CT scans. CT scans were obtained in 16 patients with CFA, who had undergone two CT examinations (6 to 43 months, mean 25.1 months apart), were reviewed focusing on the changes in size of the cystic spaces in honeycombing. The mechanism of enlargement of cystic spaces was investigated using microscopic serial sections of autopsied specimens. In 15 of 16 patients, the cystic spaces in honeycombing were larger on the second examination. Histologically, stenosis of bronchioles and slit-like structures between cysts and bronchioles were detected in addition to alveolar septal dissolution and bronchiolectasis. Both the bronchiolar stenosis and the slit-like gaps have the potential to work as check-valves and increase the volume of cystic spaces. Therefore, in the evaluation of CFA, large cysts should be interpreted with caution to avoid misinterpretation of the cysts as bullae associated with emphysema. From the results of this correlative study, we suggest that a check-valve effect is an important mechanism in the formation of large cysts in honeycomb lung.

Aged↗

Hypertension and neuronal degeneration in excised rat spinal cord studied by high-b value q-space diffusion magnetic resonance imaging.

Hypertension is one of the major risk factors of stroke and vascular dementia (VaD). We used stroke prone spontaneous hypertensive rats (SPSHRs) as a model for neuronal degeneration frequently occurring in humans with vascular disease. Recently, high b value q-space diffusion-weighted imaging (DWI) was shown to be very sensitive to the pathophysiological state of the white matter. We studied the spinal cords of SPSHR rats ex vivo after the appearance of motor impairments using diffusion anisotropy and q-space diffusion imaging (measured at a high b value of up to 1 x 10(5) s/mm(2)). The diffusion anisotropy images computed from low b value data set (b(max) approximately 2500 s/mm(2)) showed a small but statistically significant decrease (approximately 12%, P < 0.05) in the diffusion anisotropy in the spinal cords of the SPSHR group as compared to control rats. However, more significant changes were found in the high b value q-space diffusion images. The q-space displacement values in the white matter of the SPSHR group were found to be higher by more than 70% (P < 0.002) than that of the control group. These observations concurred with electron microscopy (EM) that showed significant demyelination in the spinal cords of the SPSHR group. These results seem to indicate that high b value q-space DWI might be a sensitive method for following demyelination and axonal loss associated with vascular insults.

Animals↗

Foley balloon to tamponade bleeding in the retropubic space.

BACKGROUND: Hemorrhage from the retropubic space is a well-described complication of the tension-free vaginal tape procedure that can be difficult to control with conservative measures. CASE: A 40-year-old female patient underwent tension-free vaginal tape procedure to treat stress incontinence. The procedure was complicated by persistent intraoperative bleeding from the retropubic space. The hemorrhage was refractory to digital tamponade but was successfully controlled by tamponade with a Foley catheter. The catheter was inserted with use of the urology guide wire from the vagina along the path of the tunneler into the retropubic space and inflated, successfully controlling the hemorrhage. CONCLUSION: Persistent bleeding during tension-free vaginal tape procedure from the retropubic space can be controlled with a Foley catheter placed from the vagina into the space of Retzius.

Adult↗

Repeated acquisition of a spatial navigation task in mice: effects of spacing of trials and of unilateral middle cerebral artery occlusion.

The working memory version of the Morris water escape task, the repeated acquisition task, consists of trial pairs in which an animal is started twice from the same start position. Animals have mastered this task when they need less time to find the platform in the second of the two trials. In this study, study, male C57BL mice were trained on this task with massed, spaced, or spaced delay trials in which there was a 90-min delay between the first and second trials of a pair. The mice trained with spaced trials learned the repeated acquisition task, whereas the mice trained with massed or spaced delay trials were not consistently able to do so. When the mice had reached a stable baseline performance, the middle cerebral artery (MCA) was occluded or the mice were sham-operated. Then, the effects of the MCA occlusion (MCA-O) on the performance in the repeated acquisition tasks were studied. MCA occlusion hardly affected the performance in this task, irrespective of the spacing condition of the trials, although surgery per se seemed to have a transient disruptive effect.

Animals↗

A simplified approach to the spaces of the suprahyoid neck.

CT and MR imaging permit exquisite visualization of the complex spatial anatomy of the suprahyoid neck. In spite of the large body of literature devoted to these spaces, their names and locations often are difficult to learn. By knowing the spaces and their components, the radiologist can generate an anatomically based differential diagnosis. This article presents a simplified approach to the various spaces of the suprahyoid neck and their anatomic components. Each space is discussed separately and is accompanied by a table that lists a differential diagnosis based primarily on the normal anatomic contents of the space.

Carotid Arteries↗

An investigation into the production of intra-articular gas bubbles and increase in joint space in the zygapophyseal joints of the cervical spine in asymptomatic subjects after spinal manipulation.

OBJECTIVES: To analyze the size and density of cervical zygapophyseal joint spaces in asymptomatic subjects using computed tomography (CT) and plain film radiography. The joint spaces were analyzed before manipulation without traction, before manipulation with manual traction, after manipulation without traction, and after manipulation with manual traction. The data obtained before the manipulation were compared with data obtained after the manipulation to determine if significant alterations occurred. DESIGN: Twenty-two asymptomatic subjects were placed into 1 or more of 6 possible experimental groups. In all experimental groups, except for experiment 1, the subjects underwent: (step 1) a premanipulation radiograph and/or CT scan, (step 2) a premanipulation plus traction radiograph and/or CT scan, (step 3) a postmanipulation radiograph and/or CT scan, and (step 4) a postmanipulation plus traction radiograph and/or CT scan. RESULTS: Except for experiment 2, there was no significant change in the width, area, and density values of the zygapophyseal joint spaces immediately after the manipulation in either the traction or traction-free positions of the neck, and no visible radiolucent cavities were demonstrated in any view. CONCLUSION: No evidence of gas in the joint space or obvious increase in zygapophyseal joint space width immediately after the manipulation was found. This was evident in both the traction and traction-free postmanipulation scans and plain film images. This is not consistent with the current understanding of cavitation in joints, in particular, the refractory period.

Adult↗

Is the corporate transformation of hospitals creating a new hybrid health care space? A case study of the impact of co-location of public and private hospitals in Australia.

A common feature of health reforms in western nations has been the transformation or (re)construction of health and health care as both a commodity and product. In the hospital sector, this transformation has become increasingly evident in the growth of for-profit involvement in service delivery. Investor-owned hospitals are now prominent providers of hospital care in Australia. This paper examines the changing nature of health care space through the changing portrayal and meaning of hospitals as represented by and encoded in the built environment. Public hospitals once occupied 'pride of place'. In contrast, up to the early 1980s, the private sector was seen as a cottage industry. However, increased levels of state subsidisation and government incentives and pro-market policies, combined with market-based opportunities for profit generation, have seen the emergence of large private hospital chains with a new corporate image to hospital care and the blurring of 'public' and 'private'. A significant factor in the reconstruction of hospital space in Australia has been the co-location of private and public hospitals. Co-location is a popular strategy proffered by State governments and one that has been quickly acted on by corporate providers. Using Mayne Health Ltd, Australia's largest for-profit hospital chain, and four specific case studies, this paper explores four variants of co-location. Each of these examples represent a different public and private hospital space. The growth of for-profit hospital chains signifies a new phase in the delivery of health care in Australia but also importantly the creation of a new hybridised 'health care' space. This space is neither private nor public but a reflection of the economic, political and social processes underlying this transformation.

Australia↗

Comparison of pericranium and eggshell as space fillers used in combination with guided bone regeneration: an experimental study.

PURPOSE: The purpose of the study was to determine the potential adjunctive role of 2 space fillers, used in combination with guided tissue regeneration, on bone regeneration in rat skull defects. MATERIALS AND METHODS: The study was conducted on 45 adult Wistar rats. A bilateral 6-mm-wide full-thickness skull defect was created in the parietal region of each animal. The right defect was chosen as the experiment site, and the left defect was left empty as a control. Each experiment site was covered by an inner and outer polytetrafluoroethylene membrane. The 45 rats were divided into 3 groups; no space filler between the 2 membranes was used in group I (n = 15), a free pericranial autograft was used as a space filler between the 2 membranes in group II (n = 15), and purified eggshell powder was used as space filler between the 2 membranes in group III (n = 15). Five animals in each group were killed at 15, 30, and 90 days. The harvested specimens were subjected to contact radiography and standard microscopic examination, and the rates of osteogenesis were assessed by a semiquantitative method. RESULTS: No evidence of bone regeneration was seen in any animals of the three groups at 15 days. At 30 days, bone regeneration only appeared in group I (P > .05). At 90 days, complete bone regeneration was observed in the group I in 3 of 5 animals (P < .05). In group II, the pericranial graft showed no osteogenic properties. In group III, the eggshell powder showed no resorption, but no osteoconduction was noticed. CONCLUSIONS: Although the osteogenic mechanism of guided tissue regeneration is not clear, this study suggests that the physical properties of the membrane are more important than the use of an adjunctive space filler.

Animals↗

Pulpal space pressure and temperature changes from Nd:YAG laser irradiation of dentin.

OBJECTIVES: To investigate pulpal space pressure and temperature after application of Nd:YAG laser, and high-speed diamond bur on dentin surface. METHODS: One and 3 W Nd:YAG laser and high-speed diamond bur were used to remove dentine from twenty extracted premolars. The pulp chambers were monitored for pressure and temperature changes with a pressure transducer and thermocouple, respectively. RESULTS: Regardless of the remaining dentin thickness (RDT), laser irradiation and high-speed diamond bur use generated an increase in pulpal space pressure and temperature (ANOVA and Fisher's LSD tests, P < 0.001). Pressure and temperature increased with an increase in laser power. Three-Watt laser irradiation caused greater changes than 1 W (1.75 kPa and 1.31 degrees C, 0.53 kPa and 0.34 degrees C, respectively). Both pulpal space pressure (P < 0.001) and temperature (P < 0.005) increased as the RDT decreased. CONCLUSIONS: Laser irradiation and the use of a high-speed diamond bur generated an increase in pulpal space pressure and temperature. Pulpal space pressure and temperature increased with an increase in energy density of laser and a decrease in RDT.

Adolescent↗

Control of metabolic energy by space systems. Part 2: possible distribution at metabolic cycle chemicals.

Assimilation of many concepts and observations on an energy force providing a control over metabolic chemical interaction with a force in space itself is possible. The force is assumed to integrate with the atomic orbits of the metabolic chemicals, leaving its path from space as a fluctuation for realisation of two components, a non-linear space-rich part and a linear space-poor part. The pair are associated by a balance leading to non-linear behaviour imposed upon an otherwise linear output of the orbital energy and the actual control is vested in the balance. Examples are cited for the integration of the fluctuation during protein and nucleoprotein function and for cyto-structural mechanisms which may allow a selection of space elements to provide for evolution of unique family elements for enhanced control, much as the optical physicists have selected squeezed light elements for refined quantal function. Methods for rational therapies emerge from these refinements.

Animals↗

Ab initio structure determination of rofecoxib from powder diffraction data using molecular packing analysis method and direct space method.

Crystal structures of a COX-II inhibitor, rofecoxib (Vioxx) were solved ab initio from X-ray powder diffraction pattern using both molecular packing analysis and direct space methods. The X-ray powder pattern was indexed into a tetragonal cell. Packing energies were generated and analyzed in eight most frequently found tetragonal space groups. The two space groups with the lowest total energy, P4(1)2(1)2 and P4(3)2(1)2, were used for direct space method with a Monte-Carlo/Simulated Annealing searching algorithm. Structural solutions obtained from direct space method were evaluated using molecular packing energy analysis. The structures solved ab initio from this work were compared to the single crystal structure deposited in the Cambridge Structural Database.

Crystallization↗