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Minimal Changes (minimal + change)
Terms modified by Minimal Changes Selected AbstractsStill-face and separation effects on depressed mother-infant interactionsINFANT MENTAL HEALTH JOURNAL, Issue 3 2007Tiffany Field Maternal emotional and physical unavailability have differential effects on infant interaction behavior as noted in a study by Field, Vega-Lahr, Scafidi, and Goldstein (1986). In that study, four-month-old infants experienced their mother's still face and a brief separation from the mother. Spontaneous interactions preceded and followed these to serve as baseline and reunion episodes. Although the infants became more negative and agitated during both conditions, the still face elicited more stressful behaviors. The present study replicated the Field et al. (1986) study but also compared infants of depressed and infants of nondepressed mothers. The infants of depressed versus those of nondepressed mothers were less interactive during the spontaneous interactions, as were their mothers, and they showed less distress behaviors during the still-face condition. During the "return to spontaneous interaction" following the still-face condition, they were also less interactive, as evidenced by fewer positive as well as fewer negative behaviors. Their mothers were also less active. The nondepressed mothers and infants were extremely active, as if trying to reinstate the initial spontaneous interaction. Minimal change occurred during the separation condition except that both groups of infants vocalized less than they had during the spontaneous interaction. During the reunion following the separation period, the infants of depressed versus nondepressed mothers were paradoxically more active, although their mothers continued to be less interactive. [source] Use of the Migraine Disability Assessment Questionnaire in Children and Adolescents With Headache: An Italian Pilot StudyHEADACHE, Issue 7 2003D. D'Amico MD Objectives.,To determine the suitability of the Migraine Disability Assessment (MIDAS) Questionnaire for assessing disability in children and adolescents with headache and to obtain preliminary information about disability in different primary headaches. Background.,During the last decade, researchers have begun to employ standardized methodologies to investigate the global impact of primary headaches. Disease-specific instruments have been developed to measure headache-related disability. The MIDAS Questionnaire, which is the most extensively studied of these instruments, was designed to assess the overall impact of headaches over the 3 months before compilation. The MIDAS Questionnaire is an optimal tool to assess headache-related disability in adults. Methods.,Ninety-five patients aged 7 to 17 years with tension-type headache, migraine, or both completed the validated Italian form of the MIDAS questionnaire on 2 occasions. Test-retest reliability was assessed by the Spearman rank correlation test. The Cronbach , assessed internal consistency. The patients answered questions about the adequacy of the questionnaire. Results.,The Cronbach , was .8. Correlation coefficients were generally high for the overall MIDAS score and for the items investigating disability in school and in family/leisure activities; they were lower for the items about housework. Most patients thought that the MIDAS Questionnaire was useful (98.9%) and that it captured the impact of their headaches (58.9%); 41% thought that questions about disability in housework were useless, 44.2% suggested adding questions regarding inability to do homework. All primary headaches had a considerable impact on daily activities, but patients with migraine tended to have lower headache frequencies and lower total disability time; those with tension-type headache suffered more days in which activities, although performed, were substantially impaired. Conclusions.,The MIDAS Questionnaire is useful for assessing disability in children and adolescents with different primary headaches. Minimal changes in the phrasing and content of the items would be sufficient to render the MIDAS specific for the younger population with headache. [source] Application of small-angle scattering to study the effects of moisture content on a native soy proteinJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 3 2008Catherine S. Kealley The nano- and microstructure of glycinin, a soybean protein, has been investigated as a function of moisture for moisture contents between 4 and 21,wt%. Glycinin exhibits peaks in the small-angle region whose positions show minimal change with X-rays for samples up to 13% moisture. However, the use of neutron scattering, and the associated enhancement in contrast, results in the Bragg peaks being well resolved up to higher moisture contents; the associated shift in peak positions between 4 and 21% moisture are consistent with the expansion of a hexagonal unit cell as a function of moisture content. A Porod slope of ,,4 indicates that the interface between the `dry' protein powder and the surrounding medium at a length-scale of at least 3,µm down to ,20,nm is smooth and sharp. Scanning electron microscopy indicates that the powders, with low moisture content, have a porous appearance, with the porosity decreasing and microstructure expanding as the moisture content increases. [source] Heterogeneity in the Growth of the Axial and Appendicular Skeleton in Boys: Implications for the Pathogenesis of Bone Fragility in MenJOURNAL OF BONE AND MINERAL RESEARCH, Issue 10 2000Michelle Bradney Abstract Men with spine fractures have reduced vertebral body (VB) volume and volumetric bone mineral density (vBMD). Men with hip fractures have reduced femoral neck (FN) volume and vBMD, site-specific deficits that may have their origins in growth. To describe the tempo of growth in regional bone size, bone mineral content (BMC), and vBMD, we measured bone length, periosteal and endocortical diameters, BMC, and vBMD using dual-energy X-ray absorptiometry in 184 boys aged between 7 and 17 years. Before puberty, growth was more rapid in the legs than in the trunk. During puberty, leg growth slowed while trunk length accelerated. Bone size was more advanced than BMC in all regions, being ,70% and ,35% of their predicted peaks at 7 years of age, respectively. At 16 years of age, bone size had reached its adult peak while BMC was still 10% below its predicted peak. The legs accounted for 48%, whereas the spine accounted for 10%, of the 1878 g BMC accrued between 7 and 17 years. Peripubertal growth contributed (i) 55% of the increase in leg length but 78% of the mineral accrued and (ii) 69% of the increase in spine length but 87% of the mineral accrued. Increased metacarpal and midfemoral cortical thickness was caused by respective periosteal expansion with minimal change in the endocortical diameter. Total femur and VB vBMD increased by 30,40% while size and BMC increased by 200,300%. Thus, growth builds a bigger but only slightly denser skeleton. We speculate that effect of disease or a risk factor during growth depends on the regions maturational stage at the time of exposure. The earlier growth of a regions size than mass, and the differing growth patterns from region to region, predispose to site-specific deficits in bone size, vBMD, or both. Regions further from their peak may be more severely affected by illness than those nearer completion of growth. Bone fragility in old age is likely to have its foundations partly established during growth. [source] Up-regulation of a growth arrest and DNA damage protein (GADD34) in the ischaemic human brain: implications for protein synthesis regulation and DNA repairNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 6 2004F. White GADD34 is a growth arrest and DNA damage inducible gene up-regulated in response to DNA damage, cell cycle arrest and apoptosis. It is thought that GADD34 may play a crucial role in cell survival in ischaemia. GADD34 expression was assessed immunohistochemically in post-mortem human hippocampal tissue obtained from patients surviving for defined periods (0,24 h; 24 h,7 days) after a cardiac arrest and in age-matched control subjects. In control brain, cytoplasm staining in GADD34 immunopositive cells was faint but present throughout the hippocampus and cortex. There was minimal change in GADD34 expression in the group surviving 0,24 h after cardiac arrest. However GADD34 immunostaining was markedly increased in selectively vulnerable regions in the 24 h,7 day survival group. Increased GADD34 staining was present in ischaemic neurones and in some morphologically normal neurones after cardiac arrest. Extensive ischaemic damage was found to correlate with elevated GADD34 immunostaining in the CA1 layer of the hippocampus (**P < 0.0016). In addition, GADD34 was found to colocalize with proliferating cell nuclear antigen in some neurones. The up-regulation of GADD34 in response to global ischaemia in the human brain plus its influence on protein synthesis and DNA repair suggests that this protein may have the potential to influence cell survival. [source] Change in sugar, sterol and fatty acid composition in banana meristems caused by sucrose-induced acclimation and its effects on cryopreservationPHYSIOLOGIA PLANTARUM, Issue 1 2006Guo-Yu Zhu To understand the mechanisms of sucrose-induced acclimation in relation to plant cryopreservation, sugars, sterols, fatty acids of different lipid fractions (neutral lipids, glycolipids and sphingolipids and phospholipids), as well as free fatty acids were analyzed in proliferating meristem cultures of different banana varieties. The four banana varieties that were selected show different post-thaw shoot regeneration rates (0,53.4%). All mentioned parameters were analyzed using (1) control meristems that were cultured on a normal sucrose concentration (0.09 M), which resulted in low survival after cryopreservation; and (2) 2-week sucrose precultured meristems (0.4 M). This sucrose preculture, essential for regeneration after cryopreservation, resulted in a significant increase of each of seven sugars detected. The ratio of stigmasterol/sitosterol (St/Si) in sucrose-pretreated meristems significantly increased. The sucrose pretreatment also resulted in a significant increase of total fatty acid content of the neutral lipid fraction and of the glycolipid and sphingolipid fraction, as well as the total free fatty acid content. The individual fatty acid content of the phospholipids was differently changed by the sucrose pretreatment for the given varieties studied. In most cases, sucrose pretreatment resulted in an increase of the double bond index (DBI) in the neutral lipids and a decrease of DBI in the glycolipids and sphingolipids, in phospholipids as well as in free fatty acids. Principal component analysis of all collected data revealed that (1) for the control material, sucrose and total sugar contents were closely linked to the post-thaw shoot regeneration, suggesting that sucrose and total sugar may be main limiting factors to survive cryopreservation; (2) accumulation of large quantities of sugars (glucose, fructose, sucrose and total sugar) in sucrose-pretreated material cannot explain the differences in survival after cryopreservation of the four banana varieties. We assume that a minimal amount of sugars is needed in meristem cultures to survive cryopreservation. Still, other limiting factors do influence the survival following the sucrose pretreatment. We observed that the parameters which are closely linked to the post-thaw shoot regeneration are a minimal change in the ratios of St/Si, the minimal change of the DBI of phospholipids and free fatty acids, as well as linoleic acid content (C18:2); and (3) inositol, raffinose, myristic acid (C14:0) and oleic acid (C18:1) were present in small quantities; however, they could be correlated to survival after cryopreservation, suggesting that they may be also involved in cryopreservation process. [source] Tubular kidney injury molecule-1 (KIM-1) in human renal disease,THE JOURNAL OF PATHOLOGY, Issue 2 2007MM van Timmeren Abstract KIM-1, a transmembrane tubular protein with unknown function, is undetectable in normal kidneys, but is markedly induced in experimental renal injury. The KIM-1 ectodomain is cleaved, detectable in urine, and reflects renal damage. KIM-1 expression in human renal biopsies and its correlation with urinary KIM-1 (uKIM-1) is unknown. In biopsies from various renal diseases (n = 102) and controls (n = 7), the fraction of KIM-1 positive tubules and different renal damage parameters were scored. Double labelling was performed for KIM-1 with macrophages (MØ), ,-smooth muscle actin (,-SMA), proximal (aquaporin-1) and distal (E-cadherin) tubular markers and a dedifferentiation marker (vimentin). uKIM-1 at the time of biopsy (n = 53) was measured by ELISA. Renal KIM-1 was significantly increased in all diseases versus controls (p < 0.05), except minimal change. KIM-1 was primarily expressed at the luminal side of dedifferentiated proximal tubules, in areas with fibrosis (,-SMA) and inflammation (MØ). Independent of the disease, renal KIM-1 correlated positively with renal damage, negatively with renal function, but not with proteinuria. uKIM-1 was increased in renal patients versus controls (p < 0.001), including minimal change, and correlated positively with tissue KIM-1 and MØ, negatively with renal function, but not with proteinuria. In conclusion, KIM-1 is upregulated in renal disease and is associated with renal fibrosis and inflammation. uKIM-1 is also associated with inflammation and renal function, and reflects tissue KIM-1, indicating that it can be used as a non-invasive biomarker in renal disease. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] Neurologic Diagnosis and Treatment in Patients with Computed Tomography and Nasal Endoscopy Negative Facial PainTHE LARYNGOSCOPE, Issue 11 2004Eric P. Paulson MD Abstract Objective: To determine the helpfulness of specialist neurology referral for patients with facial pain, a normal sinus computed tomography (CT) scan, and normal nasal endoscopy findings. Study Design: Prospective identification of patients and analysis of data approved by the Institutional Review Board. Methods: The data of 104 consecutive patients presenting with facial pain, a normal sinus CT scan, and normal nasal endoscopy findings were reviewed. The patients presented to a single rhinologist in a tertiary care institution. All patients were referred for specialist neurologic evaluation and potential treatment. Further information was obtained from a patient survey. Results: Of the 104 patients, 81 were women and 23 were men. The average age was 46 years (range, 22,85). Fifty-six had clear CT scans, 48 had minimal change, and all had negative endoscopies. Twenty-nine had previous unsuccessful sinus surgery. The average follow-up period was 10.5 months. Forty of 75 patients seeing a neurologist were seen on multiple occasions. Four percent of patients seen by a neurologist had an unsuspected serious intracranial diagnosis. The most common diagnoses were migraine (37%), rebound headache (17%), chronic daily headache (17%), and obstructive sleep apnea (16%). Overall, 58% improved on medical therapy; 60% of those with a clear CT scan improved, and 53% of those with minimal change on CT scan improved (P = .749). Conclusions: Facial pain remains a difficult symptom to diagnose and treat in rhinologic practice. Patients often undergo surgery without help. Most patients with facial pain, a normal sinus CT scan, and normal endoscopy findings benefit from neurologic consultation. Serious intracranial pathologic conditions can be excluded and diagnosis-specific pharmacogenetic therapy instituted with improvement in more than 50%. [source] South Africa's Current Transition in Temporal and Spatial ContextANTIPODE, Issue 2 2000Alan Leater This article analyses South Africa's current postapartheid transition in the light of earlier transformations of its social and economic order. The first of these prior transformations is the abolition of slavery and the shift to liberal capitalism, which took place in the early nineteenth century. The second is the rapid industrialization of the late nineteenth and early twentieth centuries. Each of these transformations, as well as the current transition, is explained as being partly the outcome of a broad shift in capitalist practice, innovated in the metropoles of the global economy. Due to South Africa's situation within global economic networks, each of these shifts, at different times, raised the threat of a dislocation in South Africa's prevailing social order. However, each prior transformation and, it will be argued, the current transition, has been ,managed' by established elites so as to ensure minimal change to the overall distribution of privilege. This conservative ,management' of shifts in capitalist practice, it is suggested, has been facilitated through South African elites' historic engagement with cultural discourses circulating across a global terrain. In this article then, contemporary South Africa is located within both material and discursive networks which have historically influenced the country's distribution of privilege. [source] Intraprostatic ethanol chemoablation via transurethral and transperineal injectionBJU INTERNATIONAL, Issue 1 2003M.K. Plante OBJECTIVES To further assess the safety and feasibility of prostatic chemoablation with ethanol and to address previous concerns associated with transperineal injection using a canine model. MATERIALS AND METHODS The study included 25 dogs; normal saline or 98% dehydrated ethanol were injected into the prostate using both routes, at volumes of 25,50% of the total prostate volume. The prostate and adjacent structures were examined grossly and histopathologically after the dogs were killed humanely at 4 h, 7 days and 12 weeks after injection. RESULTS Transperineal injection resulted in tissue necrosis in all prostates and significant extraprostatic necrosis in two of three animals treated. With transurethral injection, the control groups showed minimal change, whereas the group injected with ethanol resulted in lesions with variable necrosis and location. CONCLUSIONS Intraprostatic chemoablation is possible with ethanol injection both transperineally and transurethrally. Transperineal ethanol injections were associated with more extraprostatic necrosis. Transurethral injections resulted in larger amounts of necrosis in the prostatic parenchyma with minimal extraprostatic effects. However, the extent of prostatic necrosis/ablation was inconsistent and further research is warranted. [source] Electronic information resources in undergraduate education: an exploratory study of opportunities for student learning and independenceBRITISH JOURNAL OF EDUCATIONAL TECHNOLOGY, Issue 3 2002Liz McDowell The fast,growing array of electronic information resources is often viewed as a significant opportunity for change in education, with shifts towards increased student independence in learning. In order for this to happen students need to develop the capability to deal with information. This qualitative interview,based study examines lecturer perspectives on the roles of electronic information resources in undergraduate education. In line with the phenomenographic tradition, three functional categories of electronic information use are proposed. Firstly, the "electronic academic library" offers new opportunities for access to materials but lecturers indicated minimal change to their teaching approaches. Electronic resources were simply added to reading lists and the responsibility for developing students' information skills was seen to rest with librarians. Secondly, lecturers identified changes towards more constructivist approaches to learning, drawing upon new sources of primary data available electronically and described specific teaching approaches to assist students to develop the relevant information handling skills. Finally, lecturers were uncertain about the value of the wider information resources of the Internet/Web for students and were concerned about variable information quality and the possibilities of plagiarism. The research indicates that information use in student learning is a multi,faceted phenomenon. Much current discussion centres on the concept of information literacy which draws together information skills and subject-related skills and knowledge. Students do not merely require generic information skills but a knowledge of the discipline and the capability to handle complex information. Partnerships between academics and librarians are a way forward in helping students to develop as autonomous information users. Not only do the two professional groups offer different expertise, but they also bring different perspectives on the problematic balance between student autonomy and student support. [source] The effect of scleral flap edge apposition on intraocular pressure control in experimental trabeculectomyCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 4 2008Wayne Birchall Abstract Background:, To assess the contribution of scleral flap edge apposition to intraocular pressure (IOP) control in trabeculectomy, using a previously described and validated experimental model of guarded filtration surgery. Materials and methods:, Twelve rectangular-flap trabeculectomy operations each with two apical adjustable sutures were performed on six donor human eyes connected to a constant flow infusion with real-time IOP monitoring. Three sizes of scleral flap were created: 4 × 4 mm, 16 mm2 (n = 4), 3 × 3 mm, 9 mm2 (n = 4) or 3 × 2 mm, 6 mm2 (n = 4). Sutures were tied tightly to produce high aqueous outflow resistance, and equilibrium IOP established. The lateral and posterior edges of the scleral flap were removed, the sutures tightened again, and the new equilibrium IOP measured. Results:, Following flap closure and with intact flap edges, the mean absolute IOP for all flaps (n = 12) was 19.5 ± 3.9 mm Hg (mean ± SD, range 12.4,27 mm Hg) and following flap edge excision 18.7 ± 4.4 mm Hg (range 5.6,27.9 mm Hg), demonstrating no significant difference between flaps with edge apposition compared with those without (P = 0.33). Mean relative IOP (% of baseline) was 68.4 ± 12.1% (range 40.9,94%) with intact flap edges and 65.4 ± 14.5% (range 18.5,97.2%) following flap edge excision (P = 0.31). Flaps measuring 4 × 4 mm and 3 × 3 mm behaved in a similar manner with minimal change in equilibrium IOP following excision of flap edges. Conclusions:, In this experimental model, scleral flap edge apposition is not required for generating outflow resistance. Suture tension generated during tight flap closure produces apposition of the underside of the scleral trapdoor to the underlying bed, and it is this apposition, which determines IOP. [source] Gli3 null mice display glandular overgrowth of the developing stomachDEVELOPMENTAL DYNAMICS, Issue 4 2005Jae H. Kim Abstract The role of the Hedgehog signaling pathway in various aspects of gut development is still poorly understood. In the developing stomach, Sonic (Shh) and Indian (Ihh) hedgehog are expressed in both distinct and overlapping regions. Loss of Sonic hedgehog function in the stomach results in a glandular phenotype of intestinal transformation and overgrowth. These changes are reminiscent of the pre-malignant lesion, intestinal metaplasia. To determine the role of Hedgehog-related transcription factors, Gli2 and Gli3, in Shh signaling during stomach development, we conducted a mutant analysis of glandular stomach from Shh, Gli2, and Gli3 mutant mice. Although Gli2 principally mediates the activator function of Shh, surprisingly we observed minimal changes in glandular development in the Gli2 mutant stomach. Furthermore, Gli3, which typically functions as a repressor of Hedgehog signal, showed a striking phenocopy of the glandular expansion and intestinal transformation found in Shh mutant stomach. A reduction in apoptotic events was seen in all mutant stomachs with no appreciable changes in proliferation. Both Shh and Gli3 mutant stomachs displayed early changes of intestinal transformation but these did not impact on the overall differentiation of the gastric epithelium. Interestingly, the observation that Gli3 shares a similar glandular phenotype to Shh mutant stomach reveals a possible novel role of Gli3 activator in the developing stomach. The embryonic stomach is a unique model of the Hedgehog pathway function and one that may help to uncover some of the mechanisms underlying the development of intestinal metaplasia. Developmental Dynamics 234:984,991, 2005. © 2005 Wiley-Liss, Inc. [source] Interobserver agreement in endoscopic evaluation of reflux esophagitis using a modified Los Angeles classification incorporating grades N and M: A validation study in a cohort of Japanese endoscopistsDISEASES OF THE ESOPHAGUS, Issue 4 2008H. Miwa SUMMARY., The Los Angeles classification system is the most widely employed criteria associated with the greatest interobserver agreement among endoscopists. In Japan, the Los Angeles classification system has been modified (modified LA system) to include minimal changes as a distinct grade of reflux esophagitis, rather than as auxiliary findings. This adds a further grading M defined as minimal changes to the mucosa, such as erythema and/or whitish turbidity. The modified LA system has come to be used widely in Japan. However, there have been few reports to date that have evaluated the interobserver agreement in diagnosis when using the modified LA classification system incorporating these minimal changes as an additional grade. A total of 100 endoscopists from university hospitals and community hospitals, as well as private practices in the Osaka-Kobe area participated in the study. A total of 30 video clips of 30,40 seconds duration, mostly showing the esophagocardiac junction, were created and shown to 100 endoscopists using a video projector. The participating endoscopists completed a questionnaire regarding their clinical experience and rated the reflux esophagitis as shown in the video clips using the modified LA classification system. Agreement was assessed employing kappa (,) statistics for multiple raters. The , -value for all 91 endoscopists was 0.094, with a standard error of 0.002, indicating poor interobserver agreement. The endoscopists showed the best agreement on diagnosing grade A esophagitis (0.167), and the poorest agreement when diagnosing grade M esophagitis (0.033). The , -values for the diagnoses of grades N, M, and A esophagitis on identical video pairs were 0.275,0.315, with a standard error of 0.083,0.091, indicating fair intraobserver reproducibility among the endoscopists. The study results consistently indicate poor agreement regarding diagnoses as well as fair reproducibility of these diagnoses by endoscopists using the modified LA classification system, regardless of age, type of practice, past endoscopic experience, or current workload. However, grade M reflux esophagitis may not necessarily be irrelevant, as it may suggest an early form of reflux disease or an entirely new form of reflux esophagitis. Further research is required to elucidate the pathophysiological basis of minimal change esophagitis. [source] Ventral pallidal neurons code incentive motivation: amplification by mesolimbic sensitization and amphetamineEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 10 2005Amy J. Tindell Abstract Neurons in ventral pallidum fire to reward and its predictive cues. We tested mesolimbic activation effects on neural reward coding. Rats learned that a Pavlovian conditioned stimulus (CS+1 tone) predicted a second conditioned stimulus (CS+2 feeder click) followed by an unconditioned stimulus (UCS sucrose reward). Some rats were sensitized to amphetamine after training. Electrophysiological activity of ventral pallidal neurons to stimuli was later recorded under the influence of vehicle or acute amphetamine injection. Both sensitization and acute amphetamine increased ventral pallidum firing at CS+2 (population code and rate code). There were no changes at CS+1 and minimal changes to UCS. With a new ,Profile Analysis', we show that mesolimbic activation by sensitization/amphetamine incrementally shifted neuronal firing profiles away from prediction signal coding (maximal at CS+1) and toward incentive coding (maximal at CS+2), without changing hedonic impact coding (maximal at UCS). This pattern suggests mesolimbic activation specifically amplifies a motivational transform of CS+ predictive information into incentive salience coded by ventral pallidal neurons. Our results support incentive-sensitization predictions and suggest why cues temporally proximal to drug presentation may precipitate cue-triggered relapse in human addicts. [source] Differential sensitivity of medium- and large-sized striatal neurons to NMDA but not kainate receptor activation in the ratEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 10 2001Carlos Cepeda Abstract Infrared videomicroscopy and differential interference contrast optics were used to identify medium- and large-sized neurons in striatal slices from young rats. Whole-cell patch-clamp recordings were obtained to compare membrane currents evoked by application of N -methyl- d -aspartate (NMDA) and kainate. Inward currents and current densities induced by NMDA were significantly smaller in large- than in medium-sized striatal neurons. The negative slope conductance for NMDA currents was greater in medium- than in large-sized neurons and more depolarization was required to remove the Mg2+ blockade. In contrast, currents induced by kainate were significantly greater in large-sized neurons whilst current densities were approximately equal in both cell types. Spontaneous excitatory postsynaptic currents occurred frequently in medium-sized neurons but were relatively infrequent in large-sized neurons. Excitatory postsynaptic currents evoked by electrical stimulation were smaller in large- than in medium-sized neurons. A final set of experiments assessed a functional consequence of the differential sensitivity of medium- and large-sized neurons to NMDA. Cell swelling was used to examine changes in somatic area in both neuronal types after prolonged application of NMDA or kainate. NMDA produced a time-dependent increase in somatic area in medium-sized neurons whilst it produced only minimal changes in large interneurons. In contrast, application of kainate produced significant swelling in both medium- and large-sized cells. We hypothesize that reduced sensitivity to NMDA may be due to variations in receptor subunit composition and/or the relative density of receptors in the two cell types. These findings help define the conditions that put neurons at risk for excitotoxic damage in neurological disorders. [source] Hepatocellular carcinoma occurring in nonfibrotic liver: Epidemiologic and histopathologic analysis of 80 French casesHEPATOLOGY, Issue 2 2000Marie-Pierre Bralet M.D., Ph.D. Hepatocellular carcinoma (HCC) occurring in nonfibrotic liver represents a rare, ill-defined subgroup of HCC without cirrhosis in which mechanisms of hepatocarcinogenesis remain unclear. The aim of our study was to assess epidemiological factors and detailed histopathologic changes in the nontumoral liver of patients developing such tumors. Of 330 HCCs resected in our institution between 1985 and 1998, we retrospectively analyzed 80 cases (53 men, 27 women; mean age, 51 ± 16 years) in which the nontumoral liver showed no (n = 28) or minimal (n = 52) portal fibrosis without any septal fibrosis. In the group with no portal fibrosis there was no male predominance, and patients were significantly younger (44 ± 19 years vs. 54 ± 14 years) than those with minimal portal fibrosis. Sixty-seven tumors were typical HCCs, 8 were of fibrolamellar type, and 5 were hepatocholangiocarcinomas. Mean tumor size was 10 ± 5 cm. Risk factors for HCC development were found in 30 patients: hepatitis B (n = 17) or C (n = 2) virus infections, alcohol consumption (n = 11), and hemochromatosis (n = 1). In the nontumoral liver, periportal and lobular necrosis, mild portal inflammation, steatosis, and iron overload were present in 15%, 57%, 52%, and 54% of cases, respectively. Liver cell changes were noted in 6%. This study emphasizes the need for strict criteria to classify HCC without cirrhosis. HCC in nonfibrotic liver is a distinct subgroup in which nontumoral liver shows nonspecific minimal changes without regeneration or premalignant lesion. Etiologic factors are often unidentified, although presence of HBV infection in 21% suggests a direct oncogenic role of this virus. [source] Carbon dioxide extraction of residual chloroform from biodegradable polymersJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 5 2002Wendy S. Koegler Abstract Biodegradable polymeric devices for drug delivery and tissue engineering are often fabricated with the use of organic solvents and may still contain significant amounts of solvent (> 1 wt%) even after aggressive vacuum drying. This excess solvent can interfere with tissue response and the mechanical properties of the devices. The aim of this article is to demonstrate that liquid CO2 extraction can be used to reduce residual solvent in dense poly(L -lactide-co-glycolide) devices to 50 ppm relatively quickly and with minimal changes in architecture under some conditions. Two liquid CO2 extraction systems were developed to examine the removal of residual solvents from bar-shaped PLGA devices: (1) a low-pressure (1400 psi) batch system, and (2) a high-pressure (5000 psi) continuous-flow system. Eight hours of extraction in the high-pressure system reduced residual chloroform in 3 mm thick bars below the 50-ppm target. A simple Fickian diffusion model was fit to the extraction results. Diffusion coefficients ranged from 1.10×10,6 cm2/s to 2.64×10,6 cm2/s. The model predicts that ,1 h is needed to dry 1-mm bars to chloroform levels below 50 ppm, and 7 h are needed for 3 mm thick bars. The micro- and macroarchitectures of porous PLGA scaffolds created by particulate leaching were not significantly altered by CO2 drying if the salt used to make the pores was not removed before drying. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res (Appl Biomater) 63: 567,576, 2002 [source] Mutation of keratin 8 in patients with liver diseaseJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 9 2006Maximilian Schöniger-Hekele Abstract Background:, Epithelial tissues of the gastrointestinal tract and the liver express predominantly cytokeratin 8 and cytokeratin 18. In vitro experiments and animal studies have demonstrated a protective influence of keratin 8 and keratin 18 against toxic damage of hepatocytes. A specific mutation of keratin 8 (G61C) was found to be a genetic risk factor for the development of cryptogenic liver cirrhosis. The purpose of the present paper was therefore to determine the prevalence of cytokeratin 8 (G61C) and cytokeratin 18 mutations (Y53H) in patients with liver disease. Methods:, Overall 152 patients (male, n = 93, 61%; female, n = 59, 39%) were included in the present study. The 152 patients consisted of 107 patients with liver disease (70.4%; male, n = 71, 66.4%; female, n = 36, 33.6%) and 45 control patients (29.6%; male, n = 22, 48,9%; female, n = 23, 51,1%) without liver disease. Of the patients with liver disease 46 had alcoholic liver disease; 25, chronic hepatitis C; 15, cryptogenic liver disease; and 21, other liver diseases of various etiologies. Cytokeratin 8 and 18 genotypes were specified by polymerase chain reaction (PCR) amplification and direct sequence analysis was used to detect the previously described mutations in cytokeratin 8 (G61C) and in cytokeratin 18 (Y53H). Results:, Four out of 152 patients (male n = 2, female n = 2) with a mutation (G61C) in cytokeratin 8 were found. The etiology was alcoholic liver disease (n = 1), cryptogenic liver disease (n = 1) and idiopathic liver disease with minimal changes in liver biopsy (n = 1). Also, one out 45 disease control patients with an adenoma of the colon but without liver disease was found to carry the mutation G61C of cytokeratin 8. Therefore, the mutation G61C in cytokeratin 8 was found in 2.8% of patients with liver disease and in 2.2% of control patients without liver disease. Two of 15 patients (13.3%) with cryptogenic liver disease had the mutation G61C in cytokeratin 8 (P = 0.069 vs patients with non-cryptogenic liver disease). In the 152 patients studied, no mutation in cytokeratin 18 was found. Discussion:, The mutation G61C in the cytokeratin 8 gene was found in one patient with alcoholic liver disease and in two patients with liver disease of unknown etiology. Also, one patient without liver disease had the cytokeratin 8 G61C mutation. In summary, the cytokeratin 8 mutation G61C, which has been found to be associated with cryptogenic liver cirrhosis, was also found in the present patient population. However, the clinical relevance is yet to be determined in further investigations. [source] Changes in surface roughness and colour stability of soft denture lining materials caused by denture cleansersJOURNAL OF ORAL REHABILITATION, Issue 2 2003C. Jin summary, Soft denture lining materials were immersed into solutions of denture cleansers for 8 h at room temperature, and immersed into distilled water for the remainder of the 24-h period at 37 °C. Surface roughness of the soft denture lining materials was measured by contact type surface roughness instrument. For the colour stability test, soft denture lining materials were immersed in the denture cleansers as described above for 180 days. Finally, the colour changes of each material were quantitatively measured by a photometrical instrument to obtain the colour differences between newly processed specimen and immersed specimens (P < 0·01). An autopolymerizing silicone material, Evatouch, exhibited severe changes in surface roughness by all denture cleanser, and the generic material GC Denture Relining showed the minimal changes. Severe colour changes were also observed with some liner and cleanser combinations (P < 0·01). Except for Evatouth, the four silicone soft liners were more stable in surface roughness and in colour change than the two acrylic soft liners. One autopolymerizing silicone (GC denture relining) and one heat curing silicone (Molloplast B) demonstrated the best stability. [source] THE ANTARCTIC PSYCHROPHILE, CHLAMYDOMONAS RAUDENSIS ETTL (UWO241) (CHLOROPHYCEAE, CHLOROPHYTA), EXHIBITS A LIMITED CAPACITY TO PHOTOACCLIMATE TO RED LIGHT,JOURNAL OF PHYCOLOGY, Issue 4 2005Rachael M. Morgan-Kiss The psychrophilic Antarctic alga, Chlamydomonas raudensis Ettl (UWO241), grows under an extreme environment of low temperature and low irradiance of a limited spectral quality (blue-green). We investigated the ability of C. raudensis to acclimate to long-term imbalances in excitation caused by light quality through adjustments in photosystem stoichiometry. Log-phase cultures of C. raudensis and C. reinhardtii grown under white light were shifted to either blue or red light for 12 h. Previously, we reported that C. raudensis lacks the ability to redistribute light energy via the short-term mechanism of state transitions. However, similar to the model of mesophilic alga, C. reinhardtii, the psychrophile retained the capacity for long-term adjustment in energy distribution between PSI and PSII by modulating the levels of PSI reaction center polypeptides, PsaA/PsaB, with minimal changes in the content of the PSII polypeptide, D1, in response to changes in light quality. The functional consequences of the modulation in PSI/PSII stoichiometry in the psychrophile were distinct from those observed in C. reinhardtii. Exposure of C. raudensis to red light caused 1) an inhibition of growth and photosynthetic rates, 2) an increased reduction state of the intersystem plastoquinone pool with concomitant increases in nonphotochemical quenching, 3) an uncoupling of the major light-harvesting complex from the PSII core, and 4) differential thylakoid protein phosphorylation profiles compared with C. reinhardtii. We conclude that the characteristic low levels of PSI relative to PSII set the limit in the capacity of C. raudensis to photoacclimate to an environment enriched in red light. [source] A controlled study of imagery rehearsal for chronic nightmares in sexual assault survivors with PTSD: A preliminary reportJOURNAL OF TRAUMATIC STRESS, Issue 4 2000Barry Krakow Imagery-rehearsal therapy for chronic nightmares was assessed in a randomized, controlled study of sexual assault survivors with posttraumatic stress disorder (PTSD). Nightmares, sleep quality, and PTSD were assessed at baseline for 169 women, who were randomized into two groups: treatment (n = 87) and wait-list control (n = 82). Treatment consisted of two 3-hr sessions and one 1-hr session conducted over 5 weeks. Of 169 participants, 91 women (Treatment, n = 43, Control, n = 48) completed a 3-month follow-up and 78 did not. At follow-up, nightmare frequency and PTSD severity decreased and sleep quality improved in the treatment group with small to minimal changes in the control group. Treatment effects were moderate to high (Cohen's d ranged from 0.57 to 1.26). Notwithstanding the large dropout rate, imagery-rehearsal therapy is an effective treatment for chronic nightmares in sexual assault survivors with PTSD and is associated with improvement in sleep quality and decreases in PTSD severity. [source] Tryptophan Fluorescence in the Bacillus subtilis Phototropin-related Protein YtvA as a Marker of Interdomain Interaction,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 1 2004Aba Losi ABSTRACT The Bacillus subtilis protein YtvA, related to plant phototropins (phot), binds flavin mononucleotide (FMN) within the N-terminal light, oxygen and voltage (LOV) domain. The blue light-triggered photocycle of YtvA and phot involves the reversible formation of a covalent photoadduct between FMN and a cysteine (cys) residue. YtvA contains a single tryptophan, W103, localized on the LOV domain and conserved in all phot-LOV domains. In this study, we show that the fluorescence parameters of W103 in YtvA-LOV are markedly different from those observed in the full-length YtvA. The fluorescence quantum yields are ca 0.03 and 0.08, respectively. In YtvA-LOV, the maximum is redshifted (ca 345 vs 335 nm) and the average fluorescence lifetime shorter (2.7 vs 4.7 ns). These data indicate that W103 is located in a site of tight contact between the two domains of YtvA. In the FMN-cys adduct, selective excitation of W103 at 295 nm results in minimal changes of the fluorescence parameters with respect to the dark state. On 280 nm excitation, however, there is a detectable decrease in the fluorescence emitted from tyrosines, with concomitant increase in W103 fluorescence. This effect is reversible in the dark and might arise from a light-regulated energy transfer process from a yet unidentified tyrosine to W103. [source] Extreme temperature 6H-SiC JFET integrated circuit technologyPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 10 2009Philip G. Neudeck Abstract Extreme temperature semiconductor integrated circuits (ICs) are being developed for use in the hot sections of aircraft engines and other harsh-environment applications well above the 300 °C effective limit of silicon-on-insulator IC technology. This paper reviews progress by the NASA Glenn Research Center and Case Western Reserve University (CWRU) in the development of extreme temperature (up to 500 °C) integrated circuit technology based on epitaxial 6H-SiC junction field effect transistors (JFETs). Simple analog amplifier and digital logic gate ICs fabricated and packaged by NASA have now demonstrated thousands of hours of continuous 500 °C operation in oxidizing air atmosphere with minimal changes in relevant electrical parameters. Design, modeling, and characterization of transistors and circuits at temperatures from 24 °C to 500 °C are also described. CWRU designs for improved extreme temperature SiC JFET differential amplifier circuits are demonstrated. Areas for further technology maturation, needed prior to beneficial system insertion, are discussed. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Muscle magnetic resonance imaging involvement in muscular dystrophies with rigidity of the spineANNALS OF NEUROLOGY, Issue 2 2010Eugenio Mercuri MD Objective The aim of the study was to evaluate whether the visual analysis of muscle magnetic resonance imaging scans can identify specific patterns of muscle involvement. Methods We assessed scans from 83 patients with muscle disorders characterized by rigidity of the spine secondary to mutations in 4 different genes. The conditions studied were rigid spine syndrome (SEPN1 defects), Bethlem myopathy, and Ullrich congenital muscular dystrophy, allelic disorders caused by Col6A1, Col6A2, and Col6A3 mutations, the autosomal dominant form of Emery,Dreifuss muscular dystrophy (LMNA defects) and calpain-deficient limb girdle muscular dystrophy (CAPN3 defects). The scans of 25 patients affected by other myopathies were also reviewed as a control group. The scans were compared with the previously described patterns. Results In 82% of the scans in the study group (68/83) the patterns were classified as "typical" of 1 of the 5 forms studied, and in 7 (8%) were consistent with 1 of the reported patterns but not entirely typical. With one exception, the patterns identified were always consistent with the appropriate genetic diagnosis. The remaining scans (9%) had only minimal changes and were uninformative. None of the scans of the 25 patients in the control group had patterns that could be classified as typical of the 5 forms examined. The sensitivity to detect selective patterns in relation to the genetic diagnosis was 0.9. Interpretation These findings suggest that muscle magnetic resonance imaging could be used in clinical practice as an additional tool in the differential diagnosis of muscle disorders with prominent spinal rigidity. ANN NEUROL 2010;67:201,208 [source] LiFE Pilot Study: A randomised trial of balance and strength training embedded in daily life activity to reduce falls in older adultsAUSTRALIAN OCCUPATIONAL THERAPY JOURNAL, Issue 1 2010Lindy Clemson Background:,Exercise as a falls prevention strategy is more complex with people at risk than with the general population. The Lifestyle approach to reducing Falls through Exercise (LiFE) involves embedding balance and lower limb strength training in habitual daily routines. Methods:,A total of 34 community-residing people aged ,70 years were randomised either into the LiFE programme or into a no-intervention control group and followed up for six months. Inclusion criteria were two or more falls or an injurious fall in the past year. Results:,There were 12 falls in the intervention group and 35 in the control group. Therelative risk (RR) analysis demonstrated a significant reduction in falls (RR = 0.23; 0.07,0.83). There were indications that dynamic balance (P = 0.04 at three months) and efficacy beliefs (P = 0.04 at six months) improved for the LiFE programme participants. In general, secondary physical and health status outcomes, which were hypothesised as potential mediators of fall risk, improved minimally and inconsistently. Conclusions:,LiFE was effective in reducing recurrent falls in this at-risk sample. However, there were minimal changes in secondary measures. The study was feasible in terms of recruitment, randomisation, blinding and data collection. A larger randomised trial is needed to investigate long-term efficacy, mechanisms of benefit and clinical significance of this new intervention. [source] Partial-body exposure of human volunteers to 2450,MHz pulsed or CW fields provokes similar thermoregulatory responses,BIOELECTROMAGNETICS, Issue 4 2001Eleanor R. Adair Abstract Many reports describe data showing that continuous wave (CW) and pulsed (PW) radiofrequency (RF) fields, at the same frequency and average power density (PD), yield similar response changes in the exposed organism. During whole-body exposure of squirrel monkeys at 2450 MHz CW and PW fields, heat production and heat loss responses were nearly identical. To explore this question in humans, we exposed two different groups of volunteers to 2450,MHz CW (two females, five males) and PW (65,,s pulse width, 104,pps; three females, three males) RF fields. We measured thermophysiological responses of heat production and heat loss (esophageal and six skin temperatures, metabolic heat production, local skin blood flow, and local sweat rate) under a standardized protocol (30,min baseline, 45,min RF or sham exposure, 10,min baseline), conducted in three ambient temperatures (Ta,=,24, 28, and 31°C). At each Ta, average PDs studied were 0, 27, and 35,mW/cm2 (Specific absorption rate (SAR),=,0, 5.94, and 7.7,W/kg). Mean data for each group showed minimal changes in core temperature and metabolic heat production for all test conditions and no reliable differences between CW and PW exposure. Local skin temperatures showed similar trends for CW and PW exposure that were PD-dependent; only the skin temperature of the upper back (facing the antenna) showed a reliably greater increase (P,=,.005) during PW exposure than during CW exposure. Local sweat rate and skin blood flow were both Ta - and PD-dependent and showed greater variability than other measures between CW and PW exposures; this variability was attributable primarily to the characteristics of the two subject groups. With one noted exception, no clear evidence for a differential response to CW and PW fields was found. Bioelectromagnetics 22:246,259, 2001. © 2001 Wiley-Liss, Inc. [source] CD34+ stem cell top-ups without conditioning after initial haematopoietic stem cell transplantation for correction of incomplete haematopoietic and immunological recovery in severe congenital immunodeficienciesBRITISH JOURNAL OF HAEMATOLOGY, Issue 4 2006Claire Booth Summary Haematopoietic stem cell transplantation can be limited by ineffective haematopoiesis and poor immune recovery. A CD34+ cell infusion without conditioning has the potential to improve stem cell function with limited toxicity. Eighteen patients with congenital immunodeficiencies received CD34+ boosts for various defects. When given <1 year after the original graft, six of seven cytopenic patients achieved transfusion independence. A second cohort (n = 11) received boosts >1 year after the original graft; only minimal changes in immune function or chimaerism were noted. Unconditioned stem cell boosts have limited toxicity but should be given early after the original graft to be effective. [source] Minimally Invasive Flapless Implant Surgery: A Prospective Multicenter StudyCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2005ODhc, William Becker DDS ABSTRACT Background: Placement of implants with a minimally invasive flapless approach has the potential to minimize crestal bone loss, soft tissue inflammation, and probing depth adjacent to implants and to minimize surgical time. Purpose: The aim of this multicenter study was to evaluate implant placement using a minimally invasive one-stage flapless technique up to 2 years. Materials and Methods: Fifty-seven patients ranging in age from 24 to 86 years were recruited from three clinical centers (Tucson, AZ, USA; Tel Aviv, Israel; Göteborg, Sweden). Seventy-nine implants were placed. A small, sharp-tipped guiding drill was used to create a precise, minimally invasive initial penetration through the mucosa and into bone (Nobel Biocare, Yorba, Linda, CA, USA). Implants were placed according to the manufacturer's instructions, with minimal countersinking. The parameters evaluated were total surgical time, implant survival, bone quality and quantity, implant position by tooth type, depth from mucosal margin to bone crest, implant length, probing depth, inflammation, and crestal bone changes. At 2 years, for 79 implants placed in 57 patients, the cumulative success rate using a minimally invasive flapless method was 98.7%, indicating the loss of 1 implant. Changes in crestal bone for 77 baseline and follow-up measurements were insignificant (radiograph 1: mean 0.7 mm, SD 0.5 mm, range 2.8 mm, minimum 0.2 mm, maximum 3.0 mm; radiograph 2: mean 0.8 mm, SD 0.5 mm, range 3.4 mm, minimum 0.12 mm, maximum 3.5 mm). Using descriptive statistics for 78 patients (one implant lost), mean changes for probing depth and inflammation were clinically insignificant. The average time for implant placement was 28 minutes (minimum 10 minutes, maximum 60 minutes, SD 13.1 minutes). Average depth from mucosal margin to bone was 3.3 mm (SD 0.7 mm, minimum 2 mm, maximum 5 mm, range 3 mm). Thirty-two implants were placed in maxillae and 47 in mandibles. Conclusions: The results of this study demonstrate that following diagnostic treatment planning criteria, flapless surgery using a minimally invasive technique is a predictable procedure. The benefits of this procedure are lessened surgical time; minimal changes in crestal bone levels, probing depth, and inflammation; perceived minimized bleeding; and lessened postoperative discomfort. [source] Radiographic evaluation of marginal bone levels adjacent to parallel-screw cylinder machined-neck implants and rough-surfaced microthreaded implants using digitized panoramic radiographsCLINICAL ORAL IMPLANTS RESEARCH, Issue 6 2009Hans-Joachim Nickenig Abstract Objective: The purpose of this split-mouth study was to compare macro- and microstructure implant surfaces at the marginal bone level during a stress-free healing period and under functional loading. Material and methods: From January to February 2006, 133 implants (70 rough-surfaced microthreaded implants and 63 machined-neck implants) were inserted in the mandible of 34 patients with Kennedy Class I residual dentitions and followed until February 2008. The marginal bone level was radiographically determined, using digitized panoramic radiographs, at four time points: at implant placement (baseline level), after the healing period, after 6 months of functional loading, and at the end of follow-up. Results: The median follow-up time was 1.9 (range: 1.9,2.1) years. The machined-neck group had a mean crestal bone loss of 0.5 mm (range: 0,2.3) after the healing period, 0.8 mm after 6 months (range: 0,2.4), and 1.1 mm (range: 0,3) at the end of follow-up. The rough-surfaced microthreaded implant group had a mean bone loss of 0.1 mm (range: ,0.4,2) after the healing period, 0.4 mm (range: 0,2.1) after 6 months, and 0.5 mm (range: 0,2.1) at the end of follow-up. The two implant types showed significant differences in marginal bone levels (healing period: P=0.01; end of follow-up: P<0.01). Conclusions: Radiographic evaluation of marginal bone levels adjacent to machined-neck or rough-surfaced microthreaded implants showed that implants with the microthreaded design caused minimal changes in crestal bone levels during healing (stress-free) and under functional loading. [source] | ||||||||||||||||||||||||||||||||||