Short Intervals (short + interval)

Distribution by Scientific Domains
Distribution within Medical Sciences


Selected Abstracts


The role of prophylaxis in bleeding disorders

HAEMOPHILIA, Issue 2010
E. BERNTORP
Summary., The rationale for long-term prophylaxis in more severe forms of von Willebrand's disease (VWD) is obvious, as mucosal bleeding and haemophilia-like joint bleeds resulting in chronic morbidity may occur. However, the experience with prophylactic treatment in this group is scanty. An international VWD Prophylaxis Network (VWD PN) was established in 2006. The VWD PN will investigate prophylaxis with retrospective and prospective studies. Eighteen centres in Europe and North America are recruiting patients and an additional 40 centres are preparing for or evaluating participation. In the absence of randomized prospective studies for most rare bleeding disorders, guidelines for prophylaxis are a subject of controversy. In situations where there is a strong family history of bleeding, long-term prophylaxis is administered in selected cases. Short intervals of prophylaxis can also be given before some surgeries or during pregnancy. The benefits of prophylaxis must be balanced by the risk of side effects. Therefore, it is essential to delineate its management in a specialized comprehensive care environment. In haemophilia, decades of clinical experience and numerous retrospective and, recently, prospective studies clearly demonstrate that prophylactic treatment is superior to on-demand treatment, regardless of whether the outcome is the number of joint- or life-threatening bleeds, arthropathy evaluated by X-ray or MRI, or quality of life measured by generic or haemophilia-specific instruments. Optimal prophylactic treatment should be started early in life (primary prophylaxis) but various options exist for the dose and dose interval. These depend on the objective of treatment in the individual patient, which, in turn, is dependent on resources in the health care system. [source]


SECOND LOOK COLONOSCOPY: INDICATION AND REQUIREMENTS

DIGESTIVE ENDOSCOPY, Issue 2009
Jean-Francois Rey
Background:, There are circumstances when a colonoscopy should be repeated after a short interval following the first endoscopic procedure which has not completely fulfilled its objective. Review of the literature:, A second look colonoscopy is proposed when there remains a doubt about missed neoplastic lesions, either because the intestinal preparation was poor or because the video-endoscope did not achieved a complete course in the colon. The second look colonoscopy is also proposed at a short interval when it is suspected that the endoscopic removal of a single or of multiple neoplastic lesions was incomplete and that a complement of treatment is required. When the initial endoscopic procedure has completely fulfilled its objective, a second look colonoscopy can be proposed at longer intervals in surveillance programs. The intervals in surveillance after polypectomy are now adapted to the initial findings according to established guidelines. This also applies to the surveillance of incident focal cancer in patients suffering from a chronic inflammatory bowel disease. Conclusion:, Finally, in most developed countries, a priority is attributed to screening of colorectal cancer and focus is given on quality assurance of colonoscopy which is considered as the gold standard procedure in the secondary prevention of colorectal cancer. [source]


Darriwilian (Middle Ordovician) graptolite faunas of the Sandia Region, southern Peru

GEOLOGICAL JOURNAL, Issue 4 2010
Jörg Maletz
Abstract Ordovician graptolite faunas of Peru are restricted to a short interval in the Middle to basal Upper Ordovician, found in three regions of the country. All Peruvian graptolite faunas are strongly dominated by shallow water elements of the Atlantic Faunal Realm, represented largely by Didymograptus s. str. and Aulograptus, but a number of faunal elements of the pandemic isograptid biofacies have recently been discovered in the Sandia Region of SE Peru. Peruvian graptolite faunas are reviewed and the new records from the Sandia Region are discussed in detail. The faunas from the Purumpata and Iparo members of the San José Formation range in age approximately from the Undulograptus austrodentatus Biozone to the Holmograptus lentus Biozone (early to middle Darriwilian). The faunas provide a better understanding of faunal composition and diversity in this region and help to correlate shallow water and deeper water graptolite faunas from this time interval. Biserial graptolites are rare in most samples and usually indeterminable, but a single identifiable specimen of Undulograptus austrodentatus was found, indicating a level close to the base of the Darriwilian. A number of specimens of the genera Isograptus and Arienigraptus from the Sandia Region represent pandemic graptolite faunas of the isograptid biofacies, described for the first time from this region. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Natural history of clinically compensated hepatitis C virus,related graft cirrhosis after liver transplantation

HEPATOLOGY, Issue 4 2000
Marina Berenguer
The natural history of clinically compensated hepatitis C virus (HCV) cirrhosis after liver transplantation is unknown. This information is relevant to transplant centers to improve the management of these patients and decide the optimal timing for retransplantation. The aims of the study were (1) to describe the natural history of patients with HCV-cirrhosis transplants in a center with annual liver biopsies, and (2) to determine predictors for clinical decompensation, retransplantation, and mortality rates. A total of 49 patients with HCV-graft cirrhosis, 39 clinically compensated at histologic diagnosis of cirrhosis (post,liver transplantation cirrhosis) were included and followed up for 1 year (15 days-3.5 years). All patients tested were infected with genotype 1b. Predictive variables included histologic activity index (HAI) at post,liver transplantation cirrhosis, liver function tests, age, sex, and maintenance immunosuppression. Eighteen of 39 patients developed at least 1 episode of decompensation after a median of 7.8 months (4 days-2.6 years; 93% ascites). The cumulative probability of decompensation was 8%, 17%, and 42% at 1, 6, and 12 months, respectively. Graft and patient survival rates were 100%, 85%, and 71% and 100%, 92%, and 74% at 1, 6, and 12 months, respectively. Patient survival rates dropped significantly once decompensation developed (93%, 61%, and 41% at 1, 6, and 12 months, respectively). Variables associated with decompensation, retransplantation, and mortality rate included a high Child-Pugh score (>A), low levels of albumin at post,liver transplantation cirrhosis, and a short interval between liver transplantation and post,liver transplantation cirrhosis. The natural history of clinically compensated HCV-graft cirrhosis is shortened when compared with immunocompetent patients. If retransplantation is considered, it should be performed promptly once decompensation develops. [source]


The ,oriental' component of the Balkan flora: evidence of presence on the Thracian Plain during the Weichselian late-glacial

JOURNAL OF BIOGEOGRAPHY, Issue 5 2008
E. K. Magyari
Abstract Aim, To obtain palaeobotanical evidence enabling evaluation of the viability of the hypothesis that the ,oriental' element of the Balkan flora reached south-east Europe from Turkey prior to the Holocene, probably via the Thracian Plain during a late Quaternary glacial stage but no later than the late Weichselian. Location, Ezero wetland, northern Thracian Plain, Bulgaria. Methods, We undertook analyses of pollen and microspores, plant macrofossils, wood fragments and molluscs recovered from sediments deposited in the Ezero wetland during the late Weichselian and Weichselian late-glacial. Sediment chronology was determined using radiocarbon age estimates. Results, Six metres of sediments were recovered from the basin, of which the lower 3 m, extending from c. 15,450 cal yr bp to the early Allerød, was analysed. A major hiatus occurred after c. 13,900 cal yr bp, the overlying sediments being of late Holocene age. Palaeobotanical evidence indicates predominantly open vegetation during the Weichselian late-glacial, although macrofossil remains of woody taxa demonstrate the local presence of patches of wooded steppe and gallery forest. Changes in the composition of the steppe vegetation, and in the nature of the sediments deposited in the basin, indicate changes in climatic conditions, especially in the hydrological regime and in the moisture available to vegetation. After an initially relatively moister phase, the final centuries of the late Weichselian were drier, as was a short interval that may correlate with the Older Dryas. Moister conditions characterize intervals corresponding to the Bølling and Allerød sub-units of the Weichselian late-glacial interstadial. Although the pollen evidence is thus consistent with that from previous studies of this period in south-east Europe and south-west Asia, indicating predominantly open steppe vegetation, the macrofossil evidence indicates the persistent local presence of woody taxa. The woody taxa recorded include Celtis tournefortii -type and Juniperus cf. J. excelsa, two taxa today characteristic of the wooded steppes of Anatolia and members of the ,oriental' element of the southern Balkan flora, as well as Rosaceae Subfams. Maloideae and Prunoideae, Alnus and Fraxinus. Main conclusions, The late Weichselian vegetation of the northern Thracian Plain included patches of wooded steppe that supported members of the ,oriental' element of the modern Balkan flora. The presence of such taxa renders viable the hypothesis that they could have reached south-east Europe from Turkey via the Thracian Plain during glacial times. Such hypotheses in historical biogeography can be evaluated critically using the evidence obtained from plant macrofossil analyses in combination with that from pollen analysis. [source]


Commercial-scale Validation of Temperature-step Rearing on Growth Physiology in Turbot, Scophthalmus maximus

JOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 5 2008
Albert K. Imsland
The aim of this study was to investigate the possible benefit of "temperature-steps" (T-steps) rearing for juvenile turbot (initial weight 15.1 g) under realistic production scale and to determine whether initial growth advantage is maintained throughout the rearing period to market size. One group (called T-step 22-19-16) of juvenile turbot was reared at three different temperatures, that is, 22 C (from 17 to 60 g) followed by 19 C (from 60 to 100 g) and 16 C (>100 g); another group (called T-step 19-16) at two temperatures, that is, 19 C (from 17 to 100 g) and lowered to 16 C (>100 g); and the third group (called C16) at one constant temperature, that is, 16 C. Relative growth was significantly higher in the two T-step groups, with the T-step 19-16 showing the highest overall growth. Feed conversion efficiency was highest in the 19-16 group. Only minor effects of the experimental rearing on blood physiology were found, with one notable exception of inverse relationship between plasma glucose and growth. Overall, these findings indicate that a short interval of rearing fish at high temperature during the early juvenile phase may have a long-term effect on biomass increment in turbot. This is an important finding for the turbot industry. [source]


Sheep embryonic stem-like cells transplanted in full-thickness cartilage defects

JOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 3 2009
Maria Dattena
Abstract Articular cartilage regeneration is limited. Embryonic stem (ES) cell lines provide a source of totipotent cells for regenerating cartilage. Anatomical, biomechanical, physiological and immunological similarities between humans and sheep make this animal an optimal experimental model. This study examines the repair process of articular cartilage in sheep after transplantation of ES-like cells isolated from inner cell masses (ICMs) derived from in vitro -produced (IVP) vitrified embryos. Thirty-five ES-like colonies from 40 IVP embryos, positive for stage-specific embryonic antigens (SSEAs), were pooled in groups of two or three, embedded in fibrin glue and transplanted into osteochondral defects in the medial femoral condyles of 14 ewes. Empty defect (ED) and cell-free glue (G) in the controlateral stifle joint served as controls. The Y gene sequence was used to detect ES-like cells in the repair tissue by in situ hybridization (ISH). Two ewes were euthanized at 1 month post-operatively, three each at 2 and 6 months and four at 12 months. Repairing tissue was examined by biomechanical, macroscopic, histological, immunohistochemical (collagen type II) and ISH assays. Scores of all treatments showed no statistical significant differences among treatment groups at a given time period, although ES-like grafts showed a tendency toward a better healing process. ISH was positive in all ES-like specimens. This study demonstrates that ES-like cells transplanted into cartilage defects stimulate the repair process to promote better organization and tissue bulk. However, the small number of cells applied and the short interval between surgery and euthanasia might have negatively affected the results. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Cortical excitability in DYT-11 positive myoclonus dystonia

MOVEMENT DISORDERS, Issue 5 2008
Sabine Meunier MD
Abstract Myoclonus-dystonia (M-D) is an autosomal dominant movement disorder caused by mutations in the ,-sarcoglycan gene (DYT11). We explore pathophysiological characteristics of M-D with the hypothesis that they may be different from those of sporadic or genetic dystonia. We compared five carriers of the DYT11 gene mutation and 10 healthy controls. Using transcranial magnetic stimulation, we measured parameters assessing cortical membrane excitability (active motor threshold, aMT) and synaptic activity (short interval, sICI) and afferent (AI) intracortical inhibitions and their interaction. aMT was significantly higher in the DYT11 gene carriers than in normal subjects. The others parameters (sICI, AI and their interaction) were not different between the two groups. In DYT11 gene carriers cortical membrane excitability was impaired while parameters assessing cortical synaptic activity were normal. Opposite results have been obtained in focal sporadic and generalized DYT1 dystonias. © 2008 Movement Disorder Society [source]


Life-threatening complications associated with acute monocytic leukaemia after dental treatment

AUSTRALIAN DENTAL JOURNAL, Issue 1 2009
P Koulocheris
Abstract It is highly recommended to conduct a prophylactic check for any dental problems on patients who suffer from leukaemia before chemotherapy begins. Bacteraemia caused by oral microflora may be very dangerous for patients with haematological malignancies. However, it should be noted that the prophylactic process itself might bring about life-threatening complications if there is only a short interval between dental treatment and the beginning of chemotherapy, or if the dental treatment is too aggressive. We present a case where this prophylactic procedure produced life-threatening complications for a patient with acute myeloid leukaemia. [source]


Quality of life in 244 recipients of allogeneic bone marrow transplantation

BRITISH JOURNAL OF HAEMATOLOGY, Issue 3 2000
S. Chiodi
The number of long-term survivors after allogeneic bone marrow transplantation (BMT) has been increasing over the past years, and quality of life (QOL) has become an important end-point. We studied 244 patients undergoing an allogeneic BMT to identify factors and events influencing psychosocial outcome. Patients enrolled received the Psychosocial Adjustment to Illness Scale (PAIS) questionnaire assessing psychological and social adjustment to chronic illness or its sequelae. Eighty-two per cent of patients had a haematological disease. The median age was 28 years at BMT, and the median follow-up was 61 months. The median overall PAIS score for all patients was 56 (range 22,76): 25% (n = 61) of patients were considered to have a good QOL (, 25 percentile score); 44% (n = 108) of patients had an intermediate QOL (26,75 percentile score) and 31% (n = 75) had a poor QOL (> 75 percentile score). Factors associated with a poor QOL in multivariate analysis were: patients' age at BMT (> 25 years, P < 0·01); presence of long-term sequelae (P < 0·01); chronic graft-versus-host disease (GVHD) (P < 0·05); and a short interval from BMT (< 5 years; P < 0·05). The QOL improved with time: 12% of patients reported a good QOL within 5 years compared with 38% after this time point and, conversely, 38% reported a poor QOL within 5 years compared with 24% after this time point (P < 0·0001). Older patients had significantly poorer QOL compared with younger patients (, 25 years; P = 0·01). Females had significantly poorer scores when compared with males in the sexual (P < 0·0001) and psychological domains (P = 0·001). The data suggest that (i) one-third of patients undergoing allogeneic BMT report a poor QOL; (ii) factors associated with poor QOL are older age, presence of long-term sequelae, chronic GVHD and short follow-up; (iii) QOL is superior in long-term survivors; and (iv) BMT affects different aspects of life in males and females. A longitudinal study is ongoing to prove the effect of time on quality of life. [source]


Combination therapy with fludarabine and rituximab followed by alemtuzumab in the first-line treatment of patients with chronic lymphocytic leukemia or small lymphocytic lymphoma

CANCER, Issue 6 2008
A phase 2 trial of the Minnie Pearl Cancer Research Network
Abstract BACKGROUND The purpose of the current study was to evaluate the efficacy and toxicity of the combination of fludarabine and rituximab, followed by alemtuzumab, as first-line treatment for patients with chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL). METHODS In a nonrandomized phase 2 trial, 41 patients who had previously untreated CLL or SLL and required treatment received 4 cycles of the fludarabine and rituximab combination followed 5 weeks later by 4 weeks (12 doses) of intravenous alemtuzumab therapy. The response to treatment was evaluated after completion of treatment with fludarabine and rituximab, and again after the completion of alemtuzumab consolidation. RESULTS Initial treatment with the combination of fludarabine and rituximab was well tolerated, and produced a 71% overall response rate (13% complete response). Thirty-four patients began treatment with intravenous alemtuzumab, but this drug was relatively poorly tolerated when given at a short interval after fludarabine and rituximab, and only 20 patients (49% of total) were able to complete the prescribed course. Five patients had an improvement in their response with alemtuzumab; the final complete response rate was 21%. The median progression-free survival for the entire group was 42 months. Toxicity with alemtuzumab included infusion-related toxicity, myelosuppression, and opportunistic infections. CONCLUSIONS The intravenous schedule of alemtuzumab employed in the trial was relatively poorly tolerated in this community-based trial. The relatively low complete response rates after treatment with the combination of fludarabine and rituximab and after the completion of treatment suggest that these abbreviated courses may compromise efficacy. The generalized use of alemtuzumab as consolidation therapy cannot yet be recommended for community practice. However, optimization of the route of administration, duration of treatment, and interval after completion of induction therapy may improve efficacy, and further investigation is ongoing. Cancer 2008. © 2008 American Cancer Society. [source]


Conifers as invasive aliens: a global survey and predictive framework

DIVERSITY AND DISTRIBUTIONS, Issue 5-6 2004
David M. Richardson
ABSTRACT We summarize information on naturalized and invasive conifers (class Pinopsida) worldwide (data from 40 countries, some with remote states/territories), and contrast these findings with patterns for other gymnosperms (classes Cycadopsida, Gnetopsida and Ginkgoopsida) and for woody angiosperms. Eighty conifer taxa (79 species and one hybrid; 13% of species) are known to be naturalized, and 36 species (6%) are ,invasive'. This categorization is based on objective and conservative criteria relating to consistency of reproduction, distance of spread from founders, and degree of reliance on propagules from the founder population for persistence in areas well outside the natural range of species. Twenty-eight of the known invasive conifers belong to one family (Pinaceae) and 21 of these are in one genus (Pinus). The Cupressaceae (including Taxodiaceae) has six known invasive species (4%) in four genera, but the other four conifer families have none. There are also no known invasive species in classes Cycadopsida, Gnetopsida or Ginkgoopsida. No angiosperm family comprising predominantly trees and shrubs has proportionally as many invasive species as the Pinaceae. Besides the marked taxonomic bias in favour of Pinaceae, and Pinus in particular, invasiveness in conifers is associated with a syndrome of life-history traits: small seed mass (< 50 mg), short juvenile period (< 10 year), and short intervals between large seed crops. Cryptomeria japonica, Larix decidua, Picea sitchensis, Pinus contorta, Pinus strobus, and Pseudotsuga menziesii exemplify this syndrome. Many rare and endangered conifer species exhibit opposite characters. These results are consistent with earlier predictions made using a discriminant function derived from attributes of invasive and noninvasive Pinus species. Informative exceptions are species with small seeds (< 4 mg, e.g. Chamaecyparis spp., Pinus banksiana, Tsuga spp. , mostly limited to wet/mineral substrates) or otherwise ,non-invasive' characters (e.g. large seeds, fleshy fruits, e.g. Araucaria araucana, Pinus pinea, Taxus baccata that are dependent on vertebrates for seed dispersal). Most conifers do not require coevolved mutualists for pollination and seed dispersal. Also, many species can persist in small populations but have the genetic and reproductive capacity to colonize and increase population size rapidly. The underlying mechanisms mediating conifer invasions are thus easier to discern than is the case for most angiosperms. Further information is needed to determine the extent to which propagule pressure (widespread dissemination, abundant plantings, long history of cultivation) can compensate for low ,inherent invasiveness'. [source]


Effect of conditioning horses with short intervals at high speed on biochemical variables in blood

EQUINE VETERINARY JOURNAL, Issue S36 2006
A. LINDNER
Summary Reasons for performing study: There is limited published work on the effect of training using intensive and short intervals of exercise to condition horses for racing. Objectives: To examine the effect of conditioning horses 1, 2 or 3 x a week using 2 short fast exercise intervals on blood lactate (LA), plasma ammonia (NH3) and urea (urea) as well as creatine kinase (CK) activity. Methods: Thoroughbreds (age 4,5 years) were conditioned at near maximal speed (12,14 m/sec) over 100 m, on 2 occasions separated by a 10 min period at walk, on dirt track (conditioning exercise; CE) during a 6 week conditioning period (CP). The CE was undertaken either once (5 horses), twice (5 horses) or 3 times a week (4 horses) during a CP. Before, every 2 weeks during and after the CP, blood was drawn during the CE at 0, 2 and 4 min after each run and additionally 6 min after the 2nd run to measure blood LA and determine the maximal LA post exercise (LAmax). Plasma NH3 was measured in the same samples and the maximal NH3 post exercise (NH3max) determined. Additional blood samples were taken from the horses when stabled before the CE, and 12 and 24 h after to measure urea and CK activity in plasma. Results: There was no differential effect of the number of weekly CE on LAmax, NH3max, LA and NH3 immediately after exercise (LAO and NH30). Conditioning did not have an effect on LAmax and LAO after the 1st interval (P>0.05), but LAO after the 2nd interval was lower after conditioning. NH3max after the 1st and 2nd exercise interval decreased in response to the conditioning, but not NH3 immediately after exercise (P>0.05). Median plasma CK activity 12 h after exercise was higher than before exercise and returned to pre-exercise levels 24 h post exercise when horses were exercised once and twice/week. In contrast, the median plasma CK activity of horses exercising 3 times/week remained at the pre-exercise level 12 and 24 h post exercise (P>0.05). Conclusion: Conditioning horses with 2 intervals of 100 m at near maximal speed had a positive effect on blood LA and plasma NH3. Potential relevance: With the type of exercise examined, the fitness of racing horses can be maintained and eventually improved. In further studies the effect of increasing the number of runs in one exercise session should be investigated. [source]


Theoretical and conceptual issues in time,place discrimination

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 9 2009
Jonathon D. Crystal
Abstract The need to discover resources that are available under specific environmental constraints represents a fundamental environmental pressure on the evolution of behavior. Time,place discrimination refers to the ability to secure resources when they are available under specific temporal and spatial contingencies. This article reviews a number of examples of time,place discrimination. The review highlights theoretical and conceptual issues that are needed to behaviorally identify the mechanisms responsible for time,place performance. Next, limitations on time,place performance that may be imposed by a circadian system are described. Finally, a number of lines of research that broaden these limitations are discussed. These lines of research include studies that suggest that (i) a broad range of long intervals (outside the limited range of circadian entrainment) are timed, (ii) at least some long intervals (16,21 h) are timed with an endogenous self-sustaining oscillator, (iii) short intervals (in the range of 1,3 min) are timed with an endogenous self-sustaining oscillator, and (iv) memory for specific unique events (including when and where they occurred) is based on a circadian representation of time. It is concluded that a unified theory of timing that can retain the times of occurrence of individual events is needed. The time of occurrence of an event may be encoded not only with respect to a circadian oscillator but also with respect to other oscillators in the long-interval and short-interval ranges. [source]


Changes in variance and correlation of soil properties with scale and location: analysis using an adapted maximal overlap discrete wavelet transform

EUROPEAN JOURNAL OF SOIL SCIENCE, Issue 4 2001
R. M. Lark
Summary The magnitude of variation in soil properties can change from place to place, and this lack of stationarity can preclude conventional geostatistical and spectral analysis. In contrast, wavelets and their scaling functions, which take non-zero values only over short intervals and are therefore local, enable us to handle such variation. Wavelets can be used to analyse scale-dependence and spatial changes in the correlation of two variables where the linear model of coregionalization is inadmissible. We have adapted wavelet methods to analyse soil properties with non-stationary variation and covariation in fairly small sets of data, such as we can expect in soil survey, and we have applied them to measurements of pH and the contents of clay and calcium carbonate on a 3-km transect in Central England. Places on the transect where significant changes in the variance of the soil properties occur were identified. The scale-dependence of the correlations of soil properties was investigated by calculating wavelet correlations for each spatial scale. We identified where the covariance of the properties appeared to change and then computed the wavelet correlations on each side of the change point and compared them. The correlation of topsoil and subsoil clay content was found to be uniform along the transect at one important scale, although there were significant changes in the variance. In contrast, carbonate content and pH of the topsoil were correlated only in parts of the transect. [source]


Lag-sensitive repetition suppression effects in the anterior parahippocampal gyrus

HIPPOCAMPUS, Issue 5 2005
Craig J. Brozinsky
Abstract Single-unit recording studies of monkeys have shown that neurons in perirhinal and entorhinal cortex exhibit activity reductions following stimulus repetition, and some have suggested that these "repetition suppression" effects may represent neural signals that support recognition memory. Critically, repetition suppression effects are most pronounced at short intervals between stimulus repetitions. Here, we used event-related functional magnetic resonance imaging (fMRI) to identify repetition suppression effects in the human medial temporal lobe and determine whether these effects are sensitive to the length of the interval between repetitions. Twenty-one participants were scanned while performing a continuous recognition memory task in which the interval between item repetitions was parametrically varied from 2 to 32 intervening items. We found evidence of repetition suppression in the anterior parahippocampal gyrus, but only when the repetition interval was relatively short. Moreover, bilateral hippocampal regions showed lag-sensitive repetition effects. Our results demonstrate that activity in the human medial temporal cortex, like that of monkeys, exhibits repetition suppression effects that are sensitive to the length of the interval between repetitions. © 2005 Wiley-Liss, Inc. [source]


Comparative activity pattern during foraging of four albatross species

IBIS, Issue 1 2002
Henri Weimerskirch
The activity patterns of foraging Yellow-nosed Diomedea chlororhynchos, Sooty Phoebetria fusca, Black-browed D. melanophris impavida and Grey-headed Albatross D. chrysostoma were compared using loggers recording the timing of landing and take-offs, as well as the duration of bouts in flight or on the water, and the overall time spent in flight. The four species spent a similar proportion of their foraging time in flight (56,65%). During the day they were mostly flying (77,85% of the daylight period) whereas at night they were mainly (61,71%) sitting on the water. The amount of time spent in flight during the daytime foraging period was related to the amount of time spent sitting on the water at night. Differences between species occurred in the duration of bouts in flight and on the water as well as in the frequency of landings and in the time elapsed between successive landings. Yellow-nosed Albatrosses were more active than the other species, with more frequent short bouts in flight and more frequent successive landings at short intervals. Sooty Albatrosses landed or took-off less often than the other species and were more active just before dusk. Black-browed and Grey-headed Albatrosses were more active at night, especially the first part of the night and far from the colonies. Their trips consisted of a commuting part and a foraging part. Black-browed Albatrosses landed more often during the foraging than the commuting part, suggesting that they were not searching when travelling. The study suggests that there is no fundamental difference between the overall activity budgets of the four species although they show distinctive diet, morphology and life history traits. The differences observed between the four species were related mainly to differences in foraging technique. Comparison with the Wandering Albatross, the only species for which data were available previously, suggest that this larger species might differ completely in foraging technique from the smaller albatrosses. [source]


The Apathy Inventory: assessment of apathy and awareness in Alzheimer's disease, Parkinson's disease and mild cognitive impairment

INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 12 2002
P. H. Robert
Abstract Objective This study was designed to establish the validity and reliability of the apathy inventory (IA), a rating scale for global assessment of apathy and separate assessment of emotional blunting, lack of initiative, and lack of interest. Method Information for the IA can be obtained from the patient or from a caregiver. We evaluated 115 subjects using the IA, consisting of 19 healthy elderly subjects, 24 patients with Mild Cognitive Impairment (MCI), 12 subjects with Parkinson's disease (PD) and 60 subjects with Alzheimer's disease (AD). Results Internal consistency, item reliability, and between,rater reliability were high. A test,retest reliability study demonstrated that caregiver responses to IA questions were stable over short intervals. A concurrent validity study showed that the IA assesses apathy as effectively as the Neuro Psychiatric Inventory apathy domain. In the caregiver-based evaluation, AD subjects had significantly higher scores than controls, both for global apathy score and for the lack of interest dimension. When the AD patients were subdivided according to diagnostic criteria for apathy, apathetic patients had significantly higher scores than non apathetic patients. With the patient-based evaluations, no differences were found among the AD, MCI and control groups. The scores in the patient-based evaluations were only higher for the PD group versus the control subjects. The results also indicated that AD patients had poor awareness of their emotional blunting and lack of initiative. Conclusions The IA is a reliable method for assessing in demented and non-demented elderly subjects several dimensions of the apathetic syndrome, and also the subject's awareness of these symptoms. Copyright © 2002 John Wiley & Sons, Ltd. [source]


Is Gadolinium Enhancement Predictive of the Development of Brain Atrophy in Multiple Sclerosis?

JOURNAL OF NEUROIMAGING, Issue 4 2002
A Review of the Literature
ABSTRACT Background and Purpose. Several studies have demonstrated that brain atrophy can be detected over relatively short intervals from the earliest stages of multiple sclerosis (MS). Reviewing the published data, the authors highlight some hypothetical pathological mechanisms proposed as determinants of brain atrophy. Methods. Using the terms multiple sclerosis, MRI (magnetic resonance imaging), and brain atrophy, 181 citations were identified. The authors considered only studies with prospective designs with natural-course MS patients and/or placebo-treated patients of therapeutic trials, in which patients under-went baseline and follow-up scans with a T1-weighted gadolinium diethylenetriamine penta-acetic acid sequence (0.1 mmol/kg body weight), and correlation analyses between Gd enhancement activity and brain atrophy progression. Results. Five hundred thirty-two patients of 5 natural history studies and 5 therapeutic trial studies participated in the review process. The main observation was that in patients with a relapsing-remitting (RR) disease course, there was a correlation between Gd enhancement activity and brain atrophy progression. This correlation was not influenced by any other demographic and clinical additional data considered in the review process. Conclusions. Examination of the pathological mechanisms pro-posed in the reviewed studies led the authors to believe that inflammation is only in part responsible for the development of brain atrophy. This conclusion may have an implication for the strategies of tissue protection advocated in the early stages of the RR course and strengthen recent evidence indicating that anti-inflammatory immunomodulatory agents and immunosuppressive treatments, which predominantly act against the inflammatory component of disease activity, may not have similar effects on progressive tissue loss, either in RR or progressive MS. [source]


Balloon dilatation vs. balloon dilatation plus bile duct endoprostheses for treatment of anastomotic biliary strictures after liver transplantation

LIVER TRANSPLANTATION, Issue 1 2006
Thomas Zoepf
Biliary strictures after liver transplantation are a therapeutic challenge for endoscopy. Anastomotic strictures occur in 10% of patients after liver transplantation, leading untreated to mortality and ultimately to graft failure. Despite of successful reports, to date, there is no defined endoscopic therapy regimen for these cases. Therefore the aim of this study was to determine the most suitable concept for endoscopic treatment of post-liver transplant anastomotic strictures (PTAS). A total of 72 patients post-liver transplantation, who received endoscopic retrograde cholangiography (ERC) as a consequence of suspected biliary complications were retrospectively screened for the presence of PTAS. In all patients graft rejection or bile duct ischemia were excluded prior to ERC by liver biopsy or Doppler ultrasound respectively. We compared either balloon dilatation (BD) alone or dilatation plus placement of an increasing number of bile duct endoprostheses (BD + endoprostheses) in a retrospective analysis. A total of 25 of 75 patients showed PTAS. Overall, endoscopic therapy was successful in 22 of 25 patients (88%). BD was initially successful in 89% but showed recurrence in 62%. BD + endoprostheses was initially successful in 87%, and recurrence was observed only in 31%. All recurrences were successfully retreated by BD + endoprostheses. During 22 of 109 (20%) treatment sessions stone extraction was necessary. Complication rate was low with bacterial cholangitis in 8 of 109 (7.3%) sessions, mild pancreatitis in 10 of 109 (9%) sessions and minor bleeding in 2 of 25 (8%) sphincterotomies. Median follow-up after conclusion of endoscopic therapy is 6 months (range 1,43). In conclusion, our data confirm that endoscopic therapy of PTAS is highly effective and safe. As primarily successful BD shows a high rate of recurrence, we recommend a combination of BD followed by an increasing number and diameter of endoprostheses. Therapy sessions are effective at short intervals of every 2,3 months. Liver Transpl 12:88,94, 2006. © 2005 AASLD. [source]


Mixed-longitudinal growth of Karimojong girls and boys in Moroto District, Uganda

AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 1 2009
Sandra Gray
In this article we examine results of a mixed-longitudinal study of child and adolescent growth among agropastoral Karimojong children in Moroto District, northeast Uganda. During a 5-month period from August to December, 2004, longitudinal data were collected for a mixed sample of 104 Karimojong children, aged from birth to 18 years. During a previous study in 1998,1999,we had measured 26 of these children who then ranged in Age between 3 months and 7 years. Most of the children were small and thin relative to accepted growth standards, and prevalence of stunting and wasting in childhood was high. In the period from the end of childhood through adolescence, however, Karimojong girls showed marked variability in annual growth, with some attaining a large adult size relative to what we predicted based on their poor childhood growth. Developmental, evolutionary, and environmental determinants are considered. We conclude that growth of these children reflects exposure to environmental insults that vary unpredictably within relatively short intervals. Variability in the magnitude and timing of these insults among children from different birth-cohorts is probably sufficient to account for so-called "shifting" of growth percentiles in childhood and adolescence in this mixed sample. Am. J. Hum. Biol., 2009. © 2008 Wiley-Liss, Inc. [source]


Evaluation of instant light-response curves of chlorophyll fluorescence parameters obtained with a portable chlorophyll fluorometer on site in the field

PLANT CELL & ENVIRONMENT, Issue 12 2000
U. Rascher
ABSTRACT Miniaturized pulse-amplitude modulated photosynthesis yield analysers are primarily designed for measuring effective quantum yield (,F/Fm,) of photosystem II under momentary ambient light conditions in the field. Although this provides important ecophysiological information, it is often necessary to learn more about the potential intrinsic capacities of leaves by measuring light-response curves. Thus, instruments provide light-curve programmes, where light intensities are increased in short intervals and instant light-response curves are recorded within a few minutes. This method can be criticized because photosynthesis will most likely not be in steady state. This technical report shows that with the appropriate precautions instant light curves can nevertheless provide reliable information about cardinal points of photosynthesis. First, the geometry of the light source of the instrument in relation to the quantum sensor must be considered and quantum sensor readings must be corrected. Second, the measurements of the light-response curves must be compared with readings of effective quantum yield of photosystem II under ambient light conditions where photosynthesis is in steady state. This may show that in the critical range of the light curves either both measurements perfectly coincide or are offset against each other by a constant value (examples are given here). In the first case results of light curves can be taken at face values, and in the second case a simple correction can be applied. With these precautions and careful interpretations instant light-response curves can be an enormous advantage in ecophysiological field work. [source]


Patterns of reproduction in Malayan silvered leaf monkeys at the Bronx Zoo

AMERICAN JOURNAL OF PRIMATOLOGY, Issue 10 2009
Nichole Shelmidine
Abstract Within phylogenetic limits reproductive characteristics of a given species may vary between populations in response to ecological and social factors. For instance, in environments where high quality nutrition is readily available, the onset and speed of reproduction are often accelerated. Other influencing factors might be maternal experience or the sex of the infant. Here we present data on reproductive characteristics for the silvered leaf monkey (Trachypithecus cristatus), a medium-sized Asian colobine housed at the Wildlife Conservation Society's Bronx Zoo as a one-male group. To place the species into an appropriate phylogenetic context, we limited our comparison to other colobine species. Demographic data span 21.4 years (October 1985 to March 2007) and derive from 30 adult females (128.0 female years). Detailed behavioral data stem from a 2.2 years study (November 2002 to January 2005; 734 days, 4,225,hr). As in other Asian colobines, receptive periods were short (mean=4.3 days, n=68). This is expected for one-male groups where receptivity likely indicates, rather than conceals, ovulation. Gestation length was estimated based on a change in the pattern of sexual behavior (mean=194.6 days, n=7). It fell within the range reported for the taxon. Births occurred year round, at an early age (mean=2.9 years, n=8), at short intervals (mean=14.9 months, n=59) in combination with a short lactation (mean 12.1 months, n=9) likely due to the nearly unlimited availability of nutrition in this zoo setting. Primiparous females tended to have a longer first interbirth interval but infant survival rates were similar to multipara possibly due to the absence of predators. Maternal investment was independent of the infant's sex and birth sex ratio was even. Our results emphasize that when interpreted with caution, zoo populations yield realistic reproductive characteristics that can help fill the gap in our knowledge about colobine life history. Am. J. Primatol. 71:852,859, 2009. © 2009 Wiley-Liss, Inc. [source]


Dissociated effects of diazepam and lorazepam on short-latency afferent inhibition

THE JOURNAL OF PHYSIOLOGY, Issue 1 2005
Vincenzo Di Lazzaro
Peripheral nerve inputs have an inhibitory effect on motor cortex excitability at short intervals (short-latency afferent inhibition, SAI). This can be tested by coupling electrical stimulation of peripheral nerve with transcranial magnetic stimulation (TMS) of the motor cortex. SAI is reduced by the anticholinergic drug scopolamine, and in patients with Alzheimer's disease. Therefore, it is possible that SAI is a marker of central cholinergic activity important for memory function. The benzodiazepine lorazepam also reduces SAI. Since benzodiazepines impair memory formation, but do not do so uniformly, with a maximum amnesic effect after lorazepam but less or no effect after diazepam, we were interested in testing in this non-behavioural study to what extent the effects of lorazepam and diazepam on circuits involved in SAI could be dissociated. In addition, and for control, we tested the effects of lorazepam and diazepam on short-interval intracortical inhibition (SICI), a motor cortical inhibition mediated through the GABAA receptor. Lorazepam markedly reduced SAI, whereas diazepam slightly increased it. In contrast, both benzodiazepines uniformly increased SICI. Our findings demonstrate opposite effects of lorazepam and diazepam on SAI, an inhibition modulated by central cholinergic activity, but the same effects on SICI, a marker of neurotransmission through the GABAA receptor. This dissociation suggests, for the first time, that TMS measures of cortical inhibition provide the opportunity to segregate differences of benzodiazepine action in human central nervous system circuits. [source]


Slow-release nanoparticle-encapsulated delivery system for laryngeal injection,

THE LARYNGOSCOPE, Issue 5 2010
Vasantha L. Kolachala PhD
Abstract Objectives/Hypothesis: There is a need for a slow-release system for local delivery of therapeutics to the larynx. Most therapeutic substances, such as steroids or chemotherapeutic agents that are injected into the larynx are cleared rapidly. Repeated laryngeal injection of these substances at short intervals is impractical. Injectable encapsulated poly(lactide-co-glycolide) (PLGA) nanoparticles offer a potential slow-release delivery system for biologically active substances in the larynx. Study Design: Controlled animal study. Methods: PLGA nanoparticles were fabricated using a double emulsion method and were loaded with Texas Red-dextran (NPTR), hepatocyte growth factor (NPHGF), and bovine serum albumin (NPBSA). In vitro release of NPTR, NPBSA, and NPHGF was determined over approximately 2 weeks to assess potential duration of PLGA nanoparticle delivery. In vivo release of NPTR was assessed in a murine vocal fold injection model. The transcriptional effect of NPHGF on procollagen was measured in vitro to assess whether released growth factor retained functionality. Results: In vitro release kinetics demonstrated slow release of NPTR, NPBSA, and NPHGF over 12 to 14 days. In vitro NPTR release correlated with in vivo results. In vivo presence of NPTR occurred up to 7 days compared to 1 day for Texas Red control. In addition, NPHGF ameliorated transforming growth factor-, induced procollagen in vitro in 3T3 fibroblast cells. Conclusions: The results demonstrate the potential utility of nanoparticle encapsulation as an effective method for long-term delivery of specific drugs and biologically active substances to the larynx. Laryngoscope, 2010 [source]


Comparison of cysteinyl leukotriene concentrations between exhaled breath condensate and bronchoalveolar lavage fluid

CLINICAL & EXPERIMENTAL ALLERGY, Issue 12 2008
E. Ono
Summary Background Collection of exhaled breath condensate (EBC) is a simple, non-invasive method of obtaining samples from the airways and it can be repeated in short intervals without side effects; therefore, it provides an opportunity to monitor the changes in concentration of inflammatory mediators in the airways. However, EBC analysis still has several unresolved issues. Objective To better understand the characteristics of EBC, we compared cysteinyl leukotriene (CysLT) concentrations between bronchoalveolar lavage fluid (BALF) and EBC. We also attempted to correct CysLT concentrations in BALF and EBC diluted with saline and water vapour using biological markers. Methods EBC was collected from 14 patients with idiopathic pulmonary fibrosis before bronchoscopy. We measured CysLT concentrations and also quantified tyrosine, urea and total protein as possible biomarkers for correcting dilution. Results (1) We have validated the quantification of CysLTs in EBC. (2) Although a significant correlation was observed among tyrosine and urea concentrations in BALF, urea and total protein concentrations were below the detection limit in EBC. (3) CysLT concentrations were higher in BALF than in EBC (median, 15.96 pg/mL vs. 5.5 pg/mL; P=0.001) and there was no correlation of CysLT concentrations in BALF with those in EBC. A significant correlation of the ratio of total CysLT concentration to tyrosine concentration (CysLT/Y) in EBC with that in BALF was observed (r=0.547, P=0.043). (4) CysLT/Y in EBC correlated with serum KL-6 concentration and total cell count in BALF, and CysLT/Y in BALF also correlated with exhaled NO concentration and %VC. Conclusions CysLT/Y in EBC significantly correlated with that in BALF and some clinical parameters correlated with CysLT/Y. Tyrosine concentration may be used to correct the dilution error for CysLT concentrations, and CysLT/Y in EBC can be a surrogate marker for CysLT concentrations in BALF. [source]