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Long-term Study (long-term + study)
Selected AbstractsChronic Pain after Spinal Cord Injury: Results of a Long-Term StudyPAIN MEDICINE, Issue 7 2010Ehsan Modirian MD Abstract Objective., Chronic pain after spinal cord injury (SCI) is a common and considerable complication and may continue for a long time. Design., During a 2-year survey, 13.9 ± 3.0 years after injury, a total of 1,295 war-related spinal cord injury survivors were thoroughly examined by physical and rehabilitation specialists and all relevant data, consisting of type and site of pain as well as exacerbating or palliative factors, were recorded. Patients., The mean age of the survivors was 35.9 ± 7.2; 98.5% were male and 1.5% were female. The level of injury was cervical in 9.3%, thoracic in 67%, and lumbosacral in 23.7%, with 8.1% tetraplegic and 89.1% paraplegic. About 89.8% had complete spinal cord injuries and 10.2% had incomplete spinal cord injuries, based on sensory and motor testing. Results., Spinal cord related pain was reported in 64.9% of the subjects; 8.8% reported a history of pain but had no complaint at the time of examination, and 26.3% had never suffered from any pain. Patients suffering from lumbar spinal cord injury reported the highest percent of pain perception, with pain detected in 83.5% of these patients. Common sites of reported pain were the distal lower extremities (46.5%), proximal lower extremities (40.9%), pelvic girdle (24.5%), and upper limbs (5.7%). Conclusion., Spinal cord injury-related pain interferes with daily activities of patients and significantly influences their quality of life. [source] Long-term study of a portable field robot in urban terrainJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 8-9 2007Carl Lundberg The armed forces have a considerable amount of experience in using robots for bomb removal and mine clearing. Emerging technology also enables the targeting of other applications. To evaluate if real deployment of new technology is justified, tactical advantages gained have to be compared to drawbacks imposed. Evaluation calls for realistic tests which in turn require methods dictating how to deploy the new features. The present study has had two objectives: first, to gain a comprehensive view of a potential user of man-portable robots; second, to embed a robot system with users for assessment of present technology in real deployment. In this project we investigated an army company specialized in urban operations performing their tasks with the support of the iRobot Packbot Scout. The robot was integrated and deployed as an ordinary piece of equipment which required modifying and retraining a number of standard behaviors. The reported results were acquired through a long-term test ranging over a period of six months. This paper focuses on the characteristics of the users and their current ways of operation; how the robot was implemented and deployed. Additionally, this paper describes benefits and drawbacks from the users' perspective. A number of limitations in current robot technology are also identified. The findings show that the military relies on precise and thoroughly trained actions that can be executed with a minimum of ambiguity. To make use of robots, new behavioral schemes, which call for tactical optimization over several years, are needed. The most common application during the trials was reconnaissance inside buildings with uncertain enemy presence when time was not critical. Deploying the robot took more time than completing the task by traditional means, but in return kept the soldiers out of harm's way and enabled them to decrease weapon deployment. The range of the radio link, limited video feedback, and the bulky operator control unit were the features constraining the system's overall performance the most. On the other hand, did properties of the system, such as ruggedness, size, weight, terrain ability, and endurance, prove to match the application. The users were of the opinion that robots such as the Packbot Scout would be a valuable standard feature in urban intervention. © 2007 Wiley Periodicals, Inc. [source] Long-term study of re-infection following successful eradication of Helicobacter pylori infectionALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 9 2006E. A. B. CAMERON Summary Background ,Re-infection' with Helicobacter pylori after eradication has been estimated to occur in 0,14% of patients, although most so-called ,re-infections' occur within the first year following ,eradication' and many may actually be due to recrudescence of a temporarily suppressed infection. Aim To study the true re-infection rate, we have studied re-infection rates after eradication therapy by excluding the first year's data, minimizing the possible confounding effect of recrudescence. Methods All patients tested for H. pylori infection following eradication therapy between 1987 and 2004 were evaluated. Testing was carried out by urea breath test and gastric biopsy. Patients were included if they were found to be negative for H. pylori infection by testing at least 1 year following eradication and underwent at least one further test for H. pylori. Results 1162 patients met the inclusion criteria with median post-eradication follow-up of 3 years (1.5,14) including 4668 tests; 3319 years of follow-up were analysed. Thirteen cases of re-infection occurred (re-infection rate 0.4% per year). Conclusions This large study of H. pylori re-infection avoided cases of recrudescence by excluding the first post-eradication year. True re-infection is probably less common than previously thought. [source] Long-term study of fluticasone propionate aqueous nasal spray in acute and maintenance therapy of nasal polyposisALLERGY, Issue 6 2009R. Jankowski Background:, Topical steroids are first-line medication to control nasal polyposis (NP), a disease with long-term clinical course. Objective:, The aim of this study was to evaluate the efficacy and safety of fluticasone propionate aqueous nasal spray (FPANS) 200 ,g twice a day (bd) after 1 month of treatment, and to compare FPANS 200 ,g bd and FPANS 200 ,g once a day (od) in maintenance and long-term treatment. Methods:, Double-blind, placebo-controlled, 8-month study with three treatment periods (1-month acute period followed with 1-month maintenance period and 6-month follow-up period) was carried out. Group 1 received FPANS 200 ,g bd, during acute, maintenance and follow-up periods, Group 2 received FPANS 200 ,g bd during acute period and FPANS 200 ,g od during maintenance and follow-up periods, and Group 3 received placebo during acute and maintenance periods and FPANS 200 ,g bd during follow-up period. Endpoints were change from baseline in clinic peak nasal inspiratory flow (PNIF), domiciliary evening PNIF, intensity of symptoms and polyposis grade. Results:, After acute period and maintenance periods, FPANS 200 ,g bd was significantly more effective than placebo on all endpoints and more effective than FPANS 200 ,g od after 1-month maintenance period on clinic PNIF, evening PNIF, obstruction, percentage of days with no sense of smell and percentage of nights with no disturbances. The two doses were similar on other endpoints. After the 6-month follow-up period, there was no difference between the two doses of FPANS at all efficacy endpoints. The safety profile of FPANS did not highlight any new or unanticipated adverse events. Conclusion:, The study demonstrated the efficacy of FPANS 200 ,g bd in acute treatment and FPANS 200 ,g od as a sufficient dose to maintain a long-term efficacy in the treatment for NP. [source] Long-term study of dry matter allocation and rhizome growth in Anemone nemorosaPLANT SPECIES BIOLOGY, Issue 1 2007MARIANNE PHILIPP Abstract The rhizome system of Anemone nemorosa in a beech forest in Denmark was studied to determine how resources (dry matter) are allocated to segments of different age, and how rhizome growth is influenced by temperature and precipitation in the spring. The allocation pattern was studied by regular sampling and by experiments. In early spring, almost all movable resources in 1,4-year-old rhizome segments are used for development of leaves and flowers. Later, photosynthetic products from the above-ground parts are used for the growth of new segments (one-third to one-quarter of the resources allocated to the rhizome) or stored in segments from previous years (two-thirds to three-quarters of the resources). Thus, A. nemorosa uses the rhizome tissue for storage several times. Maximum and minimum dry weight per unit length (DWUL) was remarkably constant in 1,4-year-old rhizome segments. The DWUL of the current year's segments was half as high as that of the older segments. The differences in dry matter production across years were expressed in differences in segment length and branching, not in the DWUL of rhizomes. Unusually severe drought in the spring had a negative effect on rhizome growth, although a significant correlation between spring precipitation and rhizome growth was not detected. We found a negative correlation between the length of the growing period in spring and segment length, suggesting that a future increase in winter temperatures may cause an increase in rhizome growth. [source] CT01 IMPACT OF COMPLETION ANGIOGRAPHY AFTER SURGICAL CORONARY REVASCULARIZATIONANZ JOURNAL OF SURGERY, Issue 2007S. Kumar Background Coronary revascularization surgery does not traditionally employ angiography to assess procedural success. Early graft failure is reported up to 30% in one year (JAMA Nov 2005) may relate to technical errors or conduit problems. We hypothesize that intra-operative assessment of graft by angiography identifies graft defects and may improve the long term graft survival. Methods We have developed one of the first hybrid operation room in the USA. In one year period 203 consecutive patients (age:63+/,16, M/F:126/39) underwent coronary revascularization with angiography before decannulation. Results Of 436 grafts, 72 angiographic defects were detected in 69 grafts (17% of total grafts). There were 11% conduit defects, 3% anastomotic defects, and 3% target vessel error. Of 72 defects, 25/72 defects required minor revision, 47/72 required either surgical or percutaneous intervention. Intra-operative angiography added an average 20+/,12 minutes to the surgery and 112+/,56 ml contrast. Renal function at 24hours and 48 hours after procedure did not vary significantly between patients who did vs. those did not have revisions. There were no significant differences in cardiopulmonary bypass time, aortic cross clamp time, and length of hospital stay for patients who underwent revision compared to those who did not. Renal function, bleeding complication, transfusion were similar in patients with percutaneous vs. surgical revision. Conclusions Intraoperative graft angiography performed at the time of CABG identifies graft defects, allowing for immediate surgical or percutaneous revision. Long-term study is in progress to assess whether intra-operative completion angiography decreases the rate of early graft failure. [source] Long-term study of vascular perfusion effects following arteriovenous sheathotomy for branch retinal vein occlusionACTA OPHTHALMOLOGICA, Issue 3 2010Mahiul M. K. Muqit Abstract. Purpose:, To evaluate the perfusion effects and long-term visual outcome of pars plana vitrectomy (PPV) combined with arteriovenous sheathotomy (AVS) with or without triamcinolone for nonischaemic branch retinal vein occlusion (NI-BRVO). Methods:, Prospective, interventional case series of eight patients with NI-BRVO and haemorrhagic macular oedema. Patients underwent PPV and AVS (n = 5), or PPV, AVS and intravitreal triamcinolone (IVT, n = 3). A masked grading technique assessed fundus photographs and fluorescein angiography (FFA) following surgery. Scanning laser ophthalmoscopy/optical coherence tomography (SLO/OCT) evaluated macular oedema and outer retinal architecture. Main outcomes examined included visual acuity (VA), retinal reperfusion, collateral vessel regression, vascular dilatation, cystoid macular oedema (CMO), and ocular neovascularization. Results:, Seven of eight patients underwent uncomplicated surgery, with increased intraretinal perfusion and reduced engorgement of distal retinal veins. The mean pre-logMAR VA was 0.8 (SD 0.17) and did not improve significantly after surgery (post-logMAR 0.6, SD 0.38; p = 0.11, paired t -test). SLO/OCT showed persistent CMO in four patients, and subfoveal thinning of the photoreceptor layer. Collateral vessels disappeared at the blockage site post-AVS in 7/8 eyes, and this was associated with improved retinal perfusion. Six of eight patients developed epiretinal membrane. No patients developed ocular neovascularization. The average follow-up was 34.5 months. Conclusions:, PPV with AVS is a safe procedure, and adjunctive IVT had no additional effects on vascular perfusion. Successful decompressive surgery was followed by disappearance of collateral vessels at the BRVO blockage site and was a clinical marker for intravascular reperfusion. Long-term epiretinal gliosis and subfoveal photoreceptor atrophy limited functional and visual recovery. [source] Testing the assumptions of chronosequences in successionECOLOGY LETTERS, Issue 5 2008Edward A. Johnson Abstract Many introductory ecology textbooks illustrate succession, at least in part, by using certain classic studies (e.g. sand dunes, ponds/bogs, glacial till, and old fields) that substituted space for time (chronosequence) in determining the sequences of the succession. Despite past criticisms of this method, there is continued, often uncritical, use of chronosequences in current research on topics besides succession, including temporal changes in biodiversity, productivity, nutrient cycling, etc. To show the problem with chronosequence-based studies in general, we review evidence from studies that used non-chronosequence methods (such as long-term study of permanent plots, palynology, and stand reconstruction) to test the space-for-time substitution in four classic succession studies. In several cases, the tests have used the same locations and, in one case, the same plots as those in the original studies. We show that empirical evidence invalidates the chronosequence-based sequences inferred in these classic studies. [source] Equine dental disease Part 4: a long-term study of 400 cases: apical infections of cheek teethEQUINE VETERINARY JOURNAL, Issue 3 2000P. M. Dixon Summary Of 400 horses referred because of equine dental disease, 162 suffered from primary apical infections of their cheek teeth (CT), including 92 with maxillary CT infections and 70 with mandibular CT infections. Maxillary swellings and sinus tracts were more common (82 and 26% incidence, respectively) with infections of the rostral 3 maxillary CT, than with infections of the caudal 3 maxillary CT(39 and 5% incidence, respectively). Nasal discharge was more commonly present with caudal (95%) than rostral (23%) maxillary CT infections. Mandibular CT apical infections commonly had mandibular swellings (91%) and mandibular sinus tracts (59%) and these infections were closely related to eruption of the affected CT. A variety of treatments, including medical treatment, apical curettage, repulsion and oral extraction of affected teeth were utilised in these cases, with oral extraction appearing to be most satisfactory. Infections of caudal maxillary CT with a secondary paranasal sinusitis were most refractory to treatment, with a complete response to the initial treatment achieved in just 33% of these cases. Most other cases responded fully to their initial treatment. The long-term response to treatment was good in most cases. [source] Equine dental disease Part 3: a long-term study of 400 cases: disorders of wear, traumatic damage and idiopathic fractures, tumours and miscellaneous disorders of the cheek teethEQUINE VETERINARY JOURNAL, Issue 1 2000P. M. Dixon Summary Of 400 horses referred because of dental disorders, 349 cases were diagnosed as suffering from primary disorders of their cheek teeth. Details of 104 of these cases are presented, including 44 cases with abnormalities of wear, 26 cases with traumatic damage, 24 cases with idiopathic fractures and 10 cases with miscellaneous cheek teeth disorders including oral tumours. The long-term response to treatment was excellent in most cases, even in cases with residual secondary periodontal disease. [source] The Influence of Exogenous Testosterone on the Dynamics of Nestling Provisioning in Dark-Eyed JuncosETHOLOGY, Issue 1 2007Ethan D. Clotfelter In many songbird species, application of exogenous testosterone (T) during the breeding season has the general effects of reducing male parental investment and increasing allocation of time and energy to mating. Most studies record the number of feeding trips made by males as a function of their hormone treatment, but few have investigated the ways in which testosterone affects the dynamics of male and female provisioning behavior or the quantity of food delivered by males. We attempt to fill these gaps in our understanding of testosterone and male parental effort by utilizing data from a long-term study on the behavioral endocrinology of the dark-eyed junco (Junco hyemalis). We found that male and female feeding rates covaried positively, although to different degrees, throughout the nestling period, but that this relationship was degraded in pairs in which males were given T implants. We also found that the coefficients of variation in the duration of intervals between successive feeding trips by males and females were highly positively related in broods of older nestlings. Male hormone treatment, however, had no effect on the coefficients of variation in either male or female feeding intervals. Finally, we examined the quantity of prey delivered by males and found no significant effect of hormone treatment. [source] Risk factors for severe infection in patients with hairy cell leukemia: a long-term study of 73 patientsEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 3 2009Ghandi Damaj Abstract Although the survival of patients with hairy cell leukemia (HCL) has been improved by the therapeutic introduction of interferon , and purine analogs, it is still worsened by complications such as severe infections. In this long-term study, we identified factors influencing patient outcomes in 73 patients with HCL. Median age at diagnosis was 53 yr and the gender ratio (M/F) was 2.3. At the time of HCL diagnosis, 60 patients (82%) were symptomatic and 22 of these had an infection. After a median follow-up of 13 yr, eight patients had died of secondary cancer (n = 2), HCL progression (n = 1) and age-related complications (n = 5). The 10-yr overall survival (OS), progression-free survival and relapse rates were 91 ± 3%, 14 ± 5% and 87 ± 5%, respectively. In multivariate analyses, age >53 yr was the only factor adversely influencing OS and secondary cancer incidence, with adjusted hazard ratio (HR) of 9.30 (95%CI, 1.15,76.6; P = 0.037) and 2.80 (95%CI, 1.05,7.71; P = 0.04), respectively. Eleven patients developed severe infections. Absolute lymphocyte count (<1 × 109/L) at diagnosis was the only factor influencing the occurrence of severe infections, with an adjusted HR of 4.01 (P = 0.007). Strikingly, we did not observe any significant correlation between neutrophil or monocyte counts and the incidence of infection. We confirmed long-term survival in HCL but found a high incidence of infection , even late in the course of the disease. The absolute lymphocyte count at diagnosis is a risk factor for the occurrence of severe infections. In addition to careful monitoring of infections, prompt initiation of anti-HCL treatment should be considered in patients with low lymphocyte counts. [source] PROMISCUITY DRIVES SEXUAL SELECTION IN A SOCIALLY MONOGAMOUS BIRDEVOLUTION, Issue 9 2007Michael S. Webster Many socially monogamous species paradoxically show signs of strong sexual selection, suggesting cryptic sources of sexual competition among males. Darwin argued that sexual selection could operate in monogamous systems if breeding sex ratios are biased or if some males attract highly fecund females. Alternatively, sexual selection might result from promiscuous copulations outside the pair bond, although several recent studies have cast doubt on this possibility, in particular by showing that variance in apparent male reproductive success (number of social young) differs little from variance in actual male reproductive success (number of young sired). Our results from a long-term study of the socially monogamous splendid fairy-wren (Malurus splendens) demonstrate that such comparisons are misleading and do not adequately assess the effects of extra-pair paternity (EPP). By partitioning the opportunity for selection and calculating Bateman gradients, we show that EPP has a strong effect on male annual and lifetime fitness, whereas other proposed mechanisms of sexual selection do not. Thus, EPP drives sexual selection in this, and possibly other, socially monogamous species. [source] THE EVOLUTION OF SEXUAL SIZE DIMORPHISM IN THE HOUSE FINCH.EVOLUTION, Issue 6 2000Abstract Recent colonization of ecologically distinct areas in North America by the house finch (Carpodacus mexicanus) was accompanied by strong population divergence in sexual size dimorphism. Here we examined whether this divergence was produced by population differences in local selection pressures acting on each sex. In a long-term study of recently established populations in Alabama, Michigan, and Montana, we examined three selection episodes for each sex: selection for pairing success, overwinter survival, and within-season fecundity. Populations varied in intensity of these selection episodes, the contribution of each episode to the net selection, and in the targets of selection. Direction and intensity of selection strongly differed between sexes, and different selection episodes often favored opposite changes in morphological traits. In each population, current net selection for sexual dimorphism was highly concordant with observed sexual dimorphism,in each population, selection for dimorphism was the strongest on the most dimorphic traits. Strong directional selection on sexually dimorphic traits, and similar intensities of selection in both sexes, suggest that in each of the recently established populations, both males and females are far from their local fitness optimum, and that sexual dimorphism has arisen from adaptive responses in both sexes. Population differences in patterns of selection on dimorphism, combined with both low levels of ontogenetic integration in heritable sexually dimorphic traits and sexual dimorphism in growth patterns, may account for the close correspondence between dimorphism in selection and observed dimorphism in morphology across house finch populations. [source] Long-term responses of zooplankton to invasion by a planktivorous fish in a subarctic watercourseFRESHWATER BIOLOGY, Issue 1 2009PER-ARNE AMUNDSEN Summary 1.,Introduced or invading predators may have strong impacts on prey populations of the recipient community mediated by direct and indirect interactions. The long-term progression of predation effects, covering the invasion and establishment phase of alien predators, however, has rarely been documented. 2.,This paper documents the impact of an invasive, specialized planktivorous fish on its prey in a subarctic watercourse. Potential predation effects on the crustacean plankton, at the community, population and individual levels, were explored in a long-term study following the invasion by vendace (Coregonus albula). 3.,Over the 12-year period, the density and species richness of zooplankton decreased, smaller species became more abundant and Daphnia longispina, one of the largest cladocerans, was eliminated from the zooplankton community. 4.,Within the dominant cladocerans, including Daphnia spp., Bosmina longispina and Bosmina longirostris, the body size of ovigerous females and the size at first reproduction decreased after the arrival of the new predator. The clutch sizes of Daphnia spp. and B. longirostris also increased. 5.,Increased predation pressure following the vendace invasion induced many effects on the crustacean zooplankton, and we document comprehensive and strong direct and indirect long-term impacts of an introduced non-native predator on the native prey community. [source] Early Intervention With Almotriptan Improves Sustained Pain-free Response in Acute MigraineHEADACHE, Issue 10 2003Ninan T. Mathew MD Objective.,To determine whether treatment of migraine with almotriptan, when pain intensity is mild, improves 1- and 2-hour pain-free and sustained pain-free rates compared with treatment when pain intensity is moderate or severe. Methods.,This was a post hoc analysis derived from an open-label, multicenter, long-term study of the safety, tolerability, and efficacy of almotriptan 12.5 mg. Patients who met International Headache Society criteria for migraine with or without aura were eligible. Patients were instructed to take a single dose of almotriptan 12.5 mg at the onset of a migraine attack. Rescue medication could be taken if migraine pain had not disappeared at 2 hours. A second dose of almotriptan 12.5 mg could be taken if head pain recurred within 24 hours of the initial dose. Patients reported the intensity of pain at baseline and at 1 and 2 hours postmedication using a 4-point scale: no pain, mild, moderate, or severe pain. They also reported recurrence of pain (return of moderate or severe pain within 2 to 24 hours of taking the study medication) and use of rescue medication. Rescue medication consisted of supplemental analgesics taken for pain relief at 2 to 24 hours postdose. Ergotamines and other 5-HT1B/1D agonists were excluded as rescue medications. Based on these patient-reported end points, sustained pain-free rates, defined as pain-free at 2 hours with no recurrence from 2 to 24 hours and no use of rescue medication, were calculated. Results.,A higher proportion of migraine attacks of mild intensity were pain-free at 1 hour (35.3%) compared with attacks of moderate or severe intensity (7.5%) (P < .001). Two-hour pain-free rates also were significantly higher with mild intensity pain (76.9%) compared to moderate or severe intensity (43.9%) (P < .001). In addition, recurrence rates and use of rescue medication were reduced when attacks were treated during mild pain. Recurrence was 12.9% for mild pain versus 25.0% for moderate or severe pain (P < .001), and use of rescue medication was 9.4% for mild pain versus 17.2% for moderate or severe pain (P < .001). Sustained pain-free rates were nearly twice as high when attacks were treated during mild intensity pain (66.6%) compared with attacks treated during moderate or severe pain (36.6%) (P < .001). Conclusion.,Treatment with almotriptan 12.5 mg during migraine attacks of mild pain intensity improves 1- and 2-hour pain-free and sustained pain-free responses. [source] Long-term clinical outcome of living-donor liver transplantation for primary biliary cirrhosisHEPATOLOGY RESEARCH, Issue 2007Etsuko Hashimoto Aim:, We described the recurrence of primary biliary cirrhosis (PBC) after living donor liver transplantation (LDLT) (Liver Transplantation, 7, 2001: 588). However, since the follow-up period in that study was insufficiently long (median 35.5 months), we performed a long-term study to further characterize recurrence of PBC after LDLT. Patients:, From 1991 to 2006, 15 patients with end-stage PBC underwent LDLT at Tokyo Women's Medical University. Of these patients, we studied 8 PBC patients (age 29 to 51 years, all females) who survived LDLT for more than 5 years. The follow-up period for these patients ranged form 68 to 120 months. Immunosuppression was maintained with tacrolimus and prednisone. Laboratory examinations performed in every patient and donor before LDLT included routine biochemical studies, antimitochondrial antibody (AMA) by immunofluorescence (IF), anti-M2 by enzyme-linked immunosorbent assay as well as antinuclear antibody (ANA) by IF, and immunoglobulin. After LDLT, the same laboratory examinations were performed in patients every 6 months. Liver biopsy was performed when patients exhibited clinical or biochemical signs of graft dysfunction. In addition, protocol biopsy was performed every 1 to 2 years after LDLT. Results:, At the time of LDLT, all patients had end-stage cholestatic liver failure. Seven patients were positive for AMAand anti-M2 while 1 patient was negative for these markers but strongly positive for ANA. Donors were blood relatives in 6 cases, and 2 donors who were not blood relatives still exhibited multiple HLA matches with the recipients. At the end of the study in May 2006, all patients were doing well. On laboratory examination, mild abnormal liver function test results were found in 4 patients: 3 were probably due to recurrence of PBC, 1 resulted from nonalcoholic steatohepatitis. Comparison of the AMA titer between before LDLT and the most recent follow-up visit showed an increase in three patients, a decrease in two patients and no change in three patients. In contrast, the ANA titer increased in five patients. Histologically, strong evidence of recurrent PBC was found in 4 patients, and findings compatible with PBC were present in 2 additional patients. Conclusions:, Although the number of our patients is small, our findings confirm that PBC can recur at high frequency after LDLT. However, this complication has not developed to advanced stages and has not caused appreciable symptoms in our patients, all of whom have a good quality of life. [source] A comparison of infestation patterns by Ixodes ticks in urban and rural populations of the Common Blackbird Turdus merulaIBIS, Issue 4 2002Arnaud Gregoire Although spatial variation in the patterns of parasite infestations among host populations may have important ecological and epidemiological consequences, the causes underlying such variation are poorly known. In the context of a long-term study on the population biology of Common Blackbirds Turdus merula, we examined the prevalence and intensity of infestation by Ixodes ticks between birds living in rural vs. urban habitats. The overall prevalence of tick infestations was significantly higher in the rural habitat where 74% of individuals (n = 130) were infested. This result contrasted markedly with the situation in the urban habitat where less than 2% of individuals (n = 360) carried ticks. There was no significant effect of the sex of the host on the intensity or prevalence of tick infestations. There was a significant effect of the age of the host on tick infestations essentially due to the absence of ticks on nestlings. Possible mechanisms responsible for the differences between habitats could include differences in tick survival and/or host resistance towards ticks. Previous studies have shown higher population densities and suggested longer survival for Blackbirds in urban than in rural habitats. Given that ixodid ticks are known to transmit pathogens like Borrelia spp. to wild birds, and that Blackbirds can act as reservoirs for these pathogens, the infection patterns observed in our study area provide a suitable situation to study the interrelations between ticks, Blackbirds and pathogens. [source] Larvae of Chironomids (Insecta, Diptera) Encountered in the Mantle Cavity of Zebra Mussels, Dreissena polymorpha (Bivalvia, Dreissenidae)INTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 1 2005Sergey E. Mastitsky Abstract The paper includes data on species composition of chironomid larvae which were encountered in the mantle cavity of zebra mussels (Dreissena polymorpha) within 7 waterbodies in the Republic of Belarus. All were found to be free-living species commonly present in periphyton and/or benthos. A long-term study of the seasonal dynamics of these larvae in Dreissena did not reveal any typical pattern. Our data suppose that chironomids do not have an obligate association with zebra mussels and possibly enter their mantle cavity inadvertently. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Global warming tugs at trophic interactionsJOURNAL OF ANIMAL ECOLOGY, Issue 1 2009BARRY W. BROOK Climate change impacts are becoming increasingly evident as 1 °C warming above pre-industrial temperatures is approached. One of the signature biological effects is a shift towards earlier-timed reproduction. If individual species lack sufficient adaptive plasticity to alter phenology, they will have reduced fitness in a hotter world. Yet, a long-term study of an oak,caterpillar,songbird,sparrowhawk food web reveals that what could matter as much is if trophic interactions are disrupted. Multiple selective pressures may be triggered by climate change, leading to a tug-of-war between the need to stay in synchrony with the timing of maximum food, and the benefits of minimizing predation. [source] Apparent inferiority of first-time breeders in the kittiwake: the role of heterogeneity among age classesJOURNAL OF ANIMAL ECOLOGY, Issue 3 2000Emmanuelle Cam Summary 1.,Many studies have provided evidence that first-time breeders have a lower survival, a lower probability of success, or of breeding, in the following year. Hypotheses based on reproductive costs have often been proposed to explain this. However, because of the intrinsic relationship between age and experience, the apparent inferiority of first-time breeders at the population level may result from selection, and experience may not influence performance within each individual. In this paper we address the question of phenotypic correlations between fitness components. This addresses differences in individual quality, a prerequisite for a selection process to occur. We also test the hypothesis of an influence of experience on these components while taking age and reproductive success into account: two factors likely to play a key role in a selection process. 2.,Using data from a long-term study on the kittiwake, we found that first-time breeders have a lower probability of success, a lower survival and a lower probability of breeding in the next year than experienced breeders. However, neither experienced nor inexperienced breeders have a lower survival or a lower probability of breeding in the following year than birds that skipped a breeding opportunity. This suggests heterogeneity in quality among individuals. 3.,Failed birds have a lower survival and a lower probability of breeding in the following year regardless of experience. This can be interpreted in the light of the selection hypothesis. The inferiority of inexperienced breeders may be linked to a higher proportion of lower-quality individuals in younger age classes. When age and breeding success are controlled for, there is no evidence of an influence of experience on survival or future breeding probability. 4.,Using data from individuals whose reproductive life lasted the same number of years, we investigated the influence of experience on reproductive performance within individuals. There is no strong evidence that a process operating within individuals explains the improvement in performance observed at the population level. [source] Direct adsorption of low-density lipoprotein and lipoprotein(a) from whole blood: Results of the first clinical long-term multicenter study using DALI apheresis,JOURNAL OF CLINICAL APHERESIS, Issue 4 2002T. Bosch Abstract Direct adsorption of lipoproteins (DALI) is the first low-density lipoprotein (LDL)-apheresis technique by which atherogenic LDL and lipoprotein(a) (Lp(a)) can be selectively removed from whole blood without plasma separation. The present study was performed to evaluate the efficacy, selectivity and safety of long-term DALI apheresis. Sixty-three hypercholesterolemic coronary patients were treated by weekly DALI sessions. Initial LDL-cholesterol (C) plasma levels averaged 238 ± 87 mg/dl (range 130,681 mg/dl). On average, 34 sessions (1,45) were performed processing 1.5 patient blood volumes. The primary aim was to acutely reduce LDL-C by ,60% per session. To this end, three different adsorber sizes could be employed, i.e., DALI 500, 750, and 1,000, which were used in 4, 73, and 23% of the 2,156 sessions, respectively. On average, 7,387 ml of blood were processed in 116 min per session. This resulted in the following mean acute changes: LDL-C 198 , 63 mg/dl (,69%), Lp(a) 86 , 32 mg/dl (,64%), triglycerides 185 , 136 mg/dl (,27%). HDL-C (,11%) and fibrinogen (,15%) were not significantly influenced. The mean long-term reduction of LDL-C was 42% compared to baseline while HDL-C slightly increased in the long run (+4%). The selectivity of LDL removal was good as recoveries of albumin, immunoglobulins, and other proteins exceeded 85%. Ninety-five percent of 2,156 sessions were completely uneventful. The most frequent adverse effects were hypotension (1.2% of sessions) and paresthesia (1.1%), which were probably due to citrate anticoagulation. Access problems had to be overcome in 1.5%, adsorber and hardware problems in 0.5% of the sessions. In this multicenter long-term study, DALI apheresis proved to be an efficient, safe, and easy procedure for extracorporeal LDL and Lp(a) elimination. J. Clin. Apheresis 17:161,169, 2002. © 2002 Wiley-Liss, Inc. [source] Polymer-assisted regeneration therapy with Atrisorb® barriers in human periodontal intrabony defectsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 1 2004Lein-Tuan Hou Abstract Aim: This study compared clinical results of 40 periodontal osseous defects treated by two types of absorbable barrier materials. Material and Methods: Thirty patients (23 males and seven females) suffering from moderate to advanced periodontitis (with comparable osseous defects) were randomly assigned to receive either Atrisorb® barrier (n=22; group A) or Resolut XT® barrier (n=18; group B) therapy. Periodontal phase I treatment and oral hygiene instruction were performed before periodontal surgery. Papillary preservation, partial thickness flap, citric acid root conditioning, and decortication procedures were applied during the operation. Bone defects were filled with demineralized freeze-dried bone allograft and minocycline mixture (4:1 ratio). Postoperative care included 0.10% chlorhexidine rinse daily and antibiotic medication for 2 weeks. Clinical assessments including probing depth (PD), clinical attachment level (CAL), gingival recession (GR), plaque index (PlI), gingival index (GI), and radiographic examinations were taken at the baseline, preoperatively and at 3 and 6 months after regenerative surgery. Results: Six months following therapy, both Atrisorb® and Resolut XT® groups had achieved comparable clinical improvement in pocket reduction (3.9 versus 4.4 mm), attachment tissue gain (clinical attachment gain; 3.5 versus 3.6 mm), and reduction in the GI and in the PlI. Within-group comparisons showed significant attachment gain and pocket reduction between baseline data and those at both 3 and 6 months postoperatively (p<0.01). There were no statistically significant differences in any measured data between groups A and B. Conclusions: The results of this study indicate that a comparable and favorable regeneration of periodontal defects can be achieved with both Atrisorb® and Resolut XT® barriers. Further long-term study and histologic observations of tissue healing are needed to evaluate whether Atrisorb® is promising for clinical use. [source] Sex-specific selection and sexual size dimorphism in the waterstrider Aquarius remigisJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 2 2000Ferguson We estimated selection on adult body size for two generations in two populations of Aquarius remigis, as part of a long-term study of the adaptive significance of sexual size dimorphism (SSD). Net adult fitness was estimated from the following components: prereproductive survival, daily reproductive success (mating frequency or fecundity), and reproductive lifespan. Standardized selection gradients were estimated for total length and for thorax, abdomen, genital and mesofemur lengths. Although selection was generally weak and showed significant temporal and spatial heterogeneity, patterns were consistent with SSD. Prereproductive survival was strongly influenced by date of eclosion, but size (thorax and genital lengths in females; total and abdomen lengths in males) played a significant secondary role. Sexual selection favoured smaller males with longer external genitalia in one population. Net adult fitness was not significantly related to body size in females, but was negatively related to size (thorax and total length) in males. [source] Latitudinal and altitudinal growth patterns of brown trout Salmo trutta at different spatial scalesJOURNAL OF FISH BIOLOGY, Issue 10 2009I. Parra Spatial variation in growth of stream-dwelling brown trout Salmo trutta was explored in 13 populations using a long-term study (1993,2004) in the Bay of Biscay drainage, northern Spain. The high variability in fork length (LF) of S. trutta in the study area was similar to the body-size range found in the entire European distribution of the species. Mean LF at age varied: 0+ years, 57·4,100·7 mm; 1+ years, 111·6,176·0 mm; 2+ years, 155·6,248·4 mm and 3+ years, 194·3,290·9 mm. Average LF at age was higher in main courses and lower reaches compared with small tributaries and upper reaches. Annual specific growth rates (GL) were: 0+ to 1+ years, 0·634,0·825 mm mm,1 year,1; 1+ to 2+ years, 0·243,0·342 mm mm,1 year,1; 2+ to 3+ years, 0·166,0·222 mm mm,1 year,1, showing a great homogeneity. Regression models showed that water temperature and altitude were the major determinants of LF at age variability within the study area. A broader spatial analysis using available data from stream-dwelling S. trutta populations throughout Europe indicated a negative relationship between latitude and LF of individuals and a negative interaction between latitude and altitude. These findings support previous evidence of the pervasive role of water temperature on the LF of this species. Altitude appeared as the overall factor that includes the local variation of other variables, such as water temperature or food availability. At a larger scale, latitude was the factor that encompassed these environmental gradients and explained the differences in LF of S. trutta. In summary, LF at age in stream-dwelling S. trutta decreases with latitude in Europe, the converse of Bergmann's rule. [source] Dispersal and recruitment dynamics in the fleshy-fruited Persoonia lanceolata (Proteaceae)JOURNAL OF VEGETATION SCIENCE, Issue 6 2007Tony D. Auld Abstract Question: What is the role of dispersal, persistent soil seed banks and seedling recruitment in population persistence of fleshy-fruited obligate seeding plant species in fire-prone habitats? Location: Southeastern Australia. Methods: We used a long-term study of a shrubby, fleshy-fruited Persoonia species (Proteaceae) to examine (1) seed removal from beneath the canopy of adult plants; (2) seedling recruitment after fire; (3) the magnitude and location of the residual soil seed bank; and (4) the implications for fire management of obligate seeding species. We used demographic sampling techniques combined with Generalised Linear Modelling and regression to quantify population changes over time. Results: Most of the mature fruits (90%) on the ground below the canopy of plants were removed by Wallabia bicolor (Swamp wallaby) with 88% of seeds extracted from W. bicolor scats viable and dormant. Wallabies play an important role in moving seeds away from parent plants. Their role in occasional long distance dispersal events remains unknown. We detected almost no seed predation in situ under canopies (< 1%). Seedling recruitment was cued to fire, with post-fire seedling densities 6-7 times pre-fire adult densities. After fire, a residual soil seed bank was present, as many seeds (77-100%) remained dormant and viable at a soil depth where successful future seedling emergence is possible (0-5 cm). Seedling survival was high (> 80%) with most mortality within 2 years of emergence. Plant growth averaged 17 cm per year. The primary juvenile period of plants was 7,8 years, within the period of likely return fire intervals in the study area. We predicted that the study population increased some five-fold after the wildfire at the site. Conclusions: Residual soil seed banks are important, especially in species with long primary juvenile periods, to buffer the populations against the impact of a second fire occurring before the seed bank is replenished. [source] A long-term study of neighbour-regulated demography during a decline in forest species diversityJOURNAL OF VEGETATION SCIENCE, Issue 1 2006Lin Yi-ching Abstract Question: Did disturbance, no density-dependence of the dominant species, and negative neighbourhood interactions on rare species affect tree demography during a decline in species diversity associated with the increase of Acer saccharum from 1939,2001? Hypotheses: 1. The rise in dominance of A. saccharum was because of its advantage in disturbances and lack of density-dependence of its demography. 2. Rare species were not favoured by disturbances, including those from Dutch elm disease, and demonstrated negative neighbourhood interactions with A. saccharum. Location: Brownfield Woods in Illinois, USA. Methods: Historical maps of trees (, 7.6 cm DBH) from 1939, 1951, 1988, and 2001 in 16 quadrats (48 m × 68 m) were used to compare demography of eight tree species. Effects of disturbances, density-dependence, and neighbourhood interactions on mortality and recruitment of tree species within a 6-m radius of individual target trees were studied. Results: A. saccharum demonstrated a demographic advantage over rare species. It had lower mortality and higher recruitment rates. Disturbances facilitated recruitment of A. saccharum, but did not enhance rare species. Density-dependence of both mortality and recruitment of A. saccharum occurred, but population projection models indicated that ecological conditions became more favourable for A. saccharum in the past 62 years. Furthermore, negative neighbourhood interactions were detected between rare species and A. saccharum. The increase in neighbouring A. saccharum significantly increased mortality and reduced recruitment of the rare species. Conclusions: The general disturbance regime, enhanced by Dutch elm disease, in Brownfield Woods facilitated the rise of dominance of A. saccharum. Meanwhile, rare species declined as a result of their disadvantage in disturbance and negative neighbourhood interactions with A. saccharum. [source] Predictive models of short- and long-term survival in patients with nonbiliary cirrhosisLIVER TRANSPLANTATION, Issue 3 2003Gérald Longheval The limited number of donor organs has placed a burden on the medical community to improve patient selection and timing of liver transplantation (LT). We aim to evaluate short- and long-term survival of 124 consecutive patients with a diagnosis of nonbiliary cirrhosis. Seventeen clinical, biochemical, functional, and hemodynamic parameters were computed. Patient survival was evaluated in the short term (3 months) by logistic regression, and the predictive power of the model was evaluated using receiver operating characteristic curves and the log likelihood ratio. For the long-term (up to 5 years) prognosis, the Cox proportional model was used. During follow-up, 54 patients died and 20 patients underwent LT. In the short-term study, the Model for End-Stage Liver Disease score (including bilirubin level, international normalized ratio [INR], and creatinine level) was as predictive as our score, which contained only two independent indicators (bilirubin and creatinine levels). In the long-term study, three independent variables (albumin level, INR, and creatinine level) emerged from the Cox model, and patients were classified into three survival-risk groups according to a prognostic index (PI): ,1.039 × albumin (grams per deciliter) + 1.909 × loge INR + 1.207 × loge serum creatinine (milligrams per deciliter). Survival probabilities at 1 and 5 years were 89% and 80%, 63% and 52%, and 23% and 10% with a low, medium, and high PI, respectively. The validation study using the split-sample technique and data from independent patients confirmed that a high PI (>,2.5) identifies patients with a poor prognosis within 5 years. We thus have shown and validated that risk for death at the short and long term of patients with nonbiliary cirrhosis can be predicted with great accuracy using models containing a few simple and easily obtained objective variables, and these survival models are useful tools in clinical decision making, especially in deciding to list patients for LT and prioritization on the liver waiting list. [source] DOES RADIO TAGGING AFFECT THE SURVIVAL OR REPRODUCTION OF SMALL CETACEANS?MARINE MAMMAL SCIENCE, Issue 1 2006A TEST Abstract A long-term study of botos (inia geoffrensis) in the Brazilian Amazon permitted the comparison of survival and reproduction between 51 adults fitted with radio transmitters and an equal number that were captured and handled in the same way but released without a transmitter. For both sexes combined, 47 radio tagged botos (92.2%) survived at least three years after release compared with 42 (82.4%) without radios, equating to annual survival of 97.3% and 93.6% respectively. The difference was not statistically significant. Eight of 15 closely monitored radio tagged females were lactating at capture, and all their calves weaned successfully. Two that were pregnant at capture subsequently gave birth. The mean number of calves per year born to these 15 females after first release was 0.172 (SD = 0.107) and to 17 non-tagged was 0.174 (SD = 0.095), again a non-significant difference. These results indicate that the anchoring of packages to the dorsal fin of dolphins can be accomplished with no measurable impact on their subsequent survival or reproductive output. However, botos may be unusually robust to handling, and this study should not be used to justify using similar techniques on other species without customary caution, diligence, and expert guidance. [source] Adapting to winter in wheat: a long-term study follows parallel phenotypic and genetic changes in three experimental wheat populationsMOLECULAR ECOLOGY, Issue 3 2008JARED L. STRASBURG Abstract Drawing a direct connection between adaptive evolution at the phenotypic level and underlying genetic factors has long been a major goal of evolutionary biologists, but the genetic characterization of adaptive traits in natural populations is notoriously difficult. The study of evolution in experimental populations offers some help , initial conditions are known and changes can be tracked for extended periods under conditions more controlled than wild populations and more realistic than laboratory or greenhouse experiments. In this issue of Molecular Ecology, researchers studying experimental wheat populations over a 12-year period have demonstrated evolution in a major adaptive trait, flowering time, and parallel changes in underlying genetic variation (Rhonéet al. 2008). Their work suggests that cis -regulatory mutations at a single gene may explain most of the flowering time variation in these populations. [source] | |||||||||||||||||||||||||||||||