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Long-term Maintenance (long-term + maintenance)
Terms modified by Long-term Maintenance Selected AbstractsObesity: the science behind the managementINTERNAL MEDICINE JOURNAL, Issue 5-6 2002K. Steinbeck Abstract The prevalence of obesity is increasing in Western and Westernizing countries. The changing environment plays a major role in this increase, particularly the reduction in physical activity. There is also a strong genetic contribution to the development of obesity, although single-gene defect obesity is rare. Neither the environment nor genes is simple to modify. Obesity is an energy-balance disorder, and the human body has evolved to resist any loss of body fat. This biological drive to maintain weight is coordinated through central pathways, with the involvement of many neuropeptides. Thus, dietary restriction will induce changes designed to counter weight loss, including a fall in resting metabolic rate. The management of obesity demands reasonable goals, which focus on metabolic, rather than cosmetic, improvement. As obesity is a complex condition, multiple therapeutic strategies are required. Dietary modification, an increase in physical activity, a reduction in sedentary activity and behaviour modification all form the basis of obesity therapy. Drug therapy options at present are limited and may have a stronger role in weight maintenance. Currently, surgical management of obesity has the best long-term outcomes. Long-term maintenance of weight loss is achieved by few individuals. Those individuals who are successful are able to maintain long-term restrictive eating habits and high levels of physical activity. (Intern Med J 2002; 32: 237,241) [source] How do you initiate oestrogen therapy in a girl who has not undergone puberty?CLINICAL ENDOCRINOLOGY, Issue 1 2009Peter C. Hindmarsh Summary The physiology of puberty needs to be taken into consideration in the induction of puberty. Puberty is a relatively slow process and replacement therapy should mimic this. Long-term maintenance requires careful monitoring and long-term assessment of risk-benefit. This has not been appreciably defined in the adolescent population. Options for fertility need careful consideration and may depend on the adequacy of pubertal induction in terms of uterine development. A number of regimens are available for pubertal induction but the lack of comparisons makes it difficult to advocate for a particular regimen. There remain a number of areas of uncertainty, and future studies need to consider these issues and whether there are cardiovascular risk factor advantages to certain preparations. The long-term risks of breast and gynaecological malignancy remain uncertain. Long-term cohort studies are required to address these issues. [source] Maintenance of CCL5 mRNA stores by post-effector and memory CD8 T cells is dependent on transcription and is coupled to increased mRNA stabilityEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 10 2006Antoine Marçais Abstract Immunological memory is associated with the display of improved effector functions by cells of the adaptive immune system. The storage of untranslated mRNA coding for the CCL5 chemokine by CD8 memory cells is a new process supporting the immediate display of an effector function. Here, we show that, after induction during the primary response, high CCL5 mRNA levels are specifically preserved in CD8 T cells. We have investigated the mechanisms involved in the long-term maintenance of CCL5 mRNA levels by memory CD8 T cells. We demonstrate that the CCL5 mRNA half-life is increased in memory CD8 T cells and that these cells constitutively transcribe ccl5 gene. By inhibiting ccl5 transcription using IL-4, we demonstrate the essential role of transcription in the maintenance of CCL5 mRNA stores. Finally, we show that these stores are spontaneously reconstituted when the inhibitory signal is removed, indicating that the transcription of ccl5 is a default feature of memory CD8 T cells imprinted in their genetic program. [source] CD4 T cells guarantee optimal competitive fitness of CD8 memory T cellsEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 1 2004Pål Johansen Abstract We studied the contribution of CD4 T cell help to survival and competitive fitness of CD8 memory T cells specific for influenza virus nucleoprotein. In agreement with recent studies, the optimal generation of functional memory CD8 T cells required CD4 help, although long-term maintenance of resting CD8 memory T cells did not absolutely depend on the presence of CD4 T cells. Nonetheless, CD4 T cells were essential during differentiation of CD8 memory T cells to imprint on them the capacity to compete effectively with other memory T cells. CD8 memory cells generated with help survived better in secondary polyclonal hosts, and co-transfer into lymphopenic hosts together with "un-helped" CD8 memory cells showed improved homeostatic expansion of CD8 memory cells that had been generated with CD4 help. Therefore, the requirement for CD4 help in CD8 T cell memory extends to homeostatic parameters that ensure the maintenance and competitive fitness of memory clones. [source] Local and descending circuits regulate long-term potentiation and zif268 expression in spinal neuronsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2006Lars Jørgen Rygh Abstract Long-term potentiation (LTP), a use dependent long-lasting modification of synaptic strength, was first discovered in the hippocampus and later shown to occur in sensory areas of the spinal cord. Here we demonstrate that spinal LTP requires the activation of a subset of superficial spinal dorsal horn neurons expressing the neurokinin-1 receptor (NK1-R) that have previously been shown to mediate certain forms of hyperalgesia. These neurons participate in local spinal sensory processing, but are also the origin of a spino-bulbo-spinal loop driving a 5-hydroxytryptamine 3 receptor (5HT3-R)- mediated descending facilitation of spinal pain processing. Using a saporin-substance P conjugate to produce site-specific neuronal ablation, we demonstrate that NK1-R expressing cells in the superficial dorsal horn are crucial for the generation of LTP-like changes in neuronal excitability in deep dorsal horn neurons and this is modulated by descending 5HT3-R-mediated facilitatory controls. Hippocampal LTP is associated with early expression of the immediate-early gene zif268 and knockout of the gene leads to deficits in long-term LTP and learning and memory. We found that spinal LTP is also correlated with increased neuronal expression of zif268 in the superficial dorsal horn and that zif268 antisense treatment resulted in deficits in the long-term maintenance of inflammatory hyperalgesia. Our results support the suggestion that the generation of LTP in dorsal horn neurons following peripheral injury may be one mechanism whereby acute pain can be transformed into a long-term pain state. [source] Early onset of degenerative changes at nodes of Ranvier in alpha-motor axons of Cntf null (,/,) mutant miceGLIA, Issue 4 2003Kliment P. Gatzinsky Abstract The nodes of Ranvier are sites of specific interaction between Schwann cells and axons. Besides their crucial role in transmission of action potentials, the nodes of Ranvier and in particular the paranodal axon-Schwann cell networks (ASNs) are thought to function as local centers in large motor axons for removal, degradation, and disposal of organelles. In order to test whether ciliary neurotrophic factor (CNTF), which is present at high levels in the Schwann cell cytoplasm, is involved in the maintenance of these structures, we have examined lumbar ventral root nerve fibers of alpha-motor neurons by electron microscopy in 3- and 9-month-old Cntf null (,/,) mutant mice. Nerve fibers and nodes of Ranvier in 3-month-old Cntf,/, mutants appeared morphologically normal, except that ASNs were more voluminous in the mutants than in wild-type control animals at this age. In 9-month-old Cntf,/, animals, morphological changes, such as reduction in nerve fiber and axon diameter, myelin sheath disruption, and loss of ASNs at nodes of Ranvier, were observed. These findings suggest that endogenous CNTF, in addition to its role in promoting motor neuron survival and regeneration, is needed for long-term maintenance of alpha-motor nerve fibers. The premature loss of paranodal ASNs in animals lacking CNTF, which seems to be a defect related to a disturbed interaction in the nodal region between the axon and its myelinating Schwann cells, could impede the maintenance of a normal milieu in the motor axon, preceding more general neuronal damage. GLIA 42:340,349, 2003. © 2003 Wiley-Liss, Inc. [source] PKM, maintains 1-day- and 6-day-old long-term object location but not object identity memory in dorsal hippocampusHIPPOCAMPUS, Issue 6 2010Oliver Hardt Abstract Continuous activity of the atypical protein kinase C isoform M zeta (PKM,) is necessary for maintaining long-term memory acquired in aversively or appetitively motivated associative learning tasks, such as active avoidance, aversive taste conditioning, auditory and contextual fear conditioning, radial arm maze, and watermaze. Whether unreinforced, nonassociative memory will also require PKM, for long-term maintenance is not known. Using recognition memory for object location and object identity, we found that inactivating PKM, in dorsal hippocampus abolishes 1-day and 6-day-old long-term recognition memory for object location, while recognition memory for object identity was not affected by this treatment. Memory for object location persisted for no more than 35 days after training. These results suggest that the dorsal hippocampus mediates long-term memory for where, but not what things have been encountered, and that PKM, maintains this type of spatial knowledge as long as the memory exists. © 2009 Wiley-Liss, Inc. [source] Developing and maintaining protective CD8+ memory T cellsIMMUNOLOGICAL REVIEWS, Issue 1 2006Matthew A. Williams Summary:, A critical aim of vaccine-related research is to identify the mechanisms by which memory T cells are formed and maintained over long periods of time. In recent years, we have designed experiments aimed at addressing two key questions: (i) what are the factors that maintain functionally responsive CD8+ memory cells over long periods of time, and (ii) what are the signals during the early stages of infection that drive the differentiation of long-lived CD8+ memory T cells? We have identified a role for CD4+ T cells in the generation of CD8+ T-cell-mediated protection from secondary challenge. While CD4+ T cells appear to play a role in the programme of CD8 memory, we find that they are also required for the long-term maintenance of CD8+ memory T-cell numbers and function. This property is independent of CD40,CD40L interactions, and we propose a role for CD4+ T cells in maintaining the ability of CD8+ memory T cells to respond to interleukin-7 (IL-7) and IL-15. By manipulating both the time course of infection and the timing of antigen presentation to newly recruited CD8+ T cells, we also demonstrate that the programming of effector and memory potential are at least partially distinct processes. [source] Generation, persistence and plasticity of CD4 T-cell memoriesIMMUNOLOGY, Issue 4 2010Jason R. Lees Summary The development of immune memory mediated by T lymphocytes is central to durable, long-lasting protective immunity. A key issue in the field is how to direct the generation and persistence of memory T cells to elicit the appropriate secondary response to provide protection to a specific pathogen. Two prevailing views have emerged; that cellular and molecular regulators control the lineage fate and functional capacities of memory T cells early after priming, or alternatively, that populations of memory T cells are inherently plastic and subject to alterations in function and/or survival at many stages during their long-term maintenance. Here, we will review current findings in CD4 T-cell memory that suggest inherent plasticity in populations of memory CD4 T cells at all stages of their development , originating with their generation from multiple types of primed CD4 T cells, during their persistence and homeostatic turnover in response to T-cell receptor signals, and also following secondary challenge. These multiple aspects of memory CD4 T-cell flexibility contrast the more defined lineages and functions ascribed to memory CD8 T cells, suggesting a dynamic nature to memory CD4 T-cell populations and responses. The flexible attributes of CD4 T-cell memory suggest opportunities and mechanisms for therapeutic manipulation at all phases of immune memory development, maintenance and recall. [source] Biodiversity and biogeography of the islands of the Kuril ArchipelagoJOURNAL OF BIOGEOGRAPHY, Issue 9 2003Theodore W. Pietsch Abstract Aim Based on seven consecutive seasons of biotic survey and inventory of the terrestrial and freshwater plants and animals of the 30 major islands of the Kuril Archipelago, a description of the biodiversity and an analysis of the biogeography of this previously little known part of the world are provided. Location The Kuril Archipelago, a natural laboratory for investigations into the origin, subsequent evolution, and long-term maintenance of insular populations, forms the eastern boundary of the Okhotsk Sea, extending 1200 km between Hokkaido, Japan, and the Kamchatka Peninsula of Russia. A chain of more than 56 islands, the system is only slightly smaller than the Hawaiian Islands, covering an area of 15,600 km2 and providing 2409 km of coastline. Methods Collections of whole specimens of plants and animals, as well as tissue samples for future molecular studies, were made by teams of scientists from Russia, Japan, and the USA, averaging 34 people for each of the seven annual summer expeditions (1994,2000). Floral and faunal similarities between islands were evaluated by using Sorensen's coefficient of similarity. The similarity matrix resulting from pair-wise calculations was then subjected to UPGMA cluster analysis. Results Despite the relatively small geographical area of all islands combined, the Kuril Island biota is characterized by unusually high taxonomic diversity, yet endemism is very low. An example of a non-relict biota, it originated from two primary sources: a southern source, the Asian mainland by way of Sakhalin and Hokkaido, and a northern source by way of Kamchatka. The contribution of the southern source biota to the species diversity of the Kurils was considerably greater than the northern one. Main conclusion The Bussol Strait, lying between Urup and Simushir in the central Kurils, is the most significant biogeographical boundary within the Archipelago. Of lesser importance are two transitional zones, the De Vries Strait or ,Miyabe Line', which passes between Iturup and Urup in the southern Kurils, and the fourth Kuril Strait, between Onekotan and Paramushir in the northern Kurils. [source] Meta-analysis: the efficacy and safety of certolizumab pegol in Crohn's diseaseALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 6 2009L.-M. SHAO Summary Background, Certolizumab pegol is the third anti-TNF-, agent approved by the Food and Drug Administration of the United States. Aim, To provide a comprehensive up-to-date review of the efficacy and safety of certolizumab in Crohn's disease (CD). Methods, Electronic databases, including PubMed, EMBASE, the Cochrane library and the Science Citation Index, were searched to retrieve relevant trials. In addition, meeting abstracts and the reference lists of retrieved articles were reviewed for further relevant studies. Results, Three trials, enrolling a total of 1040 patients, are included in the meta-analysis to evaluate the short-term efficacy of certolizumab, which is effective for rapid induction and long-term maintenance of clinical response or remission and can improve quality of life in patients with Crohn's disease. Certolizumab is also effective for patients who have lost response to infliximab. However, its efficacy in infliximab-exposed patients is probably less than in infliximab-naive patients. Re-induction with certolizumab in patients who have flared on maintenance therapy can rescue a significant proportion of patients. There is no significant association between the efficacy of certolizumab and the baseline C-reactive protein level. In comparison with placebo, certolizumab does not increase the risk of serious adverse events. Conclusions, Certolizumab is effective and safe in treating Crohn's disease. Further studies are still required to assess its full safety profile. [source] Azathioprine without oral ciclosporin in the long-term maintenance of remission induced by intravenous ciclosporin in severe, steroid-refractory ulcerative colitisALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 12 2002E. Domènech Summary Background : Intravenous ciclosporin is considered to be the only alternative to avoid surgery in severe, steroid-refractory ulcerative colitis. In responders, some authors recommend a switch to oral ciclosporin to act as a ,bridge' until the therapeutic action of azathioprine is achieved for maintenance treatment. Aim : To report the short- and long-term outcome of intravenous ciclosporin-responsive ulcerative colitis patients treated with oral azathioprine without oral ciclosporin. Methods : The records of all patients treated with intravenous ciclosporin for severe, steroid-refractory ulcerative colitis were reviewed. Responders following treatment with azathioprine but without oral ciclosporin as maintenance therapy were included. Patients with colonic cytomegalovirus infection and/or follow-up of less than 1 year were excluded. Results : Twenty-seven patients were included. Steroids were discontinued in 24 (89%). The median follow-up was 36 months. Eighteen (75%) patients presented mild or moderate relapses, which were easily managed with salicylates or steroids. Cumulative probabilities of relapse were 42%, 72% and 77% at 1, 3 and 5 years, respectively. Eleven (40.7%) patients underwent elective colectomy. Cumulative probabilities of colectomy were 29%, 35% and 42% at 1, 3 and 5 years, respectively. No opportunistic infections were observed. Conclusions : Oral azathioprine seems to be enough to maintain long-term remission induced by intravenous ciclosporin in patients with steroid-refractory ulcerative colitis. The ,bridging step' with oral ciclosporin may not be necessary in this subset of patients, although a randomized controlled trial is warranted to confirm this hypothesis. [source] Reversion and Maintenance of Sinus Rhythm in Patients with Permanent Atrial Fibrillation by Internal Cardioversion Followed by Biatrial PacingPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 3 2002NIKOLAOS FRAGAKIS FRAGAKIS, N., et al.: Reversion and Maintenance of Sinus Rhythm in Patients with Permanent Atrial Fibrillation by Internal Cardioversion Followed by Biatrial Pacing. Patients in atrial fibrillation (AF) who fail external cardioversion are usually regarded as in permanent AF. Internal cardioversion may revert many such patients into sinus rhythm (SR) but the majority relapse rapidly into AF. We investigated whether internal cardioversion followed by biatrial pacing is an effective to restore and subsequently maintain SR in patients with permanent AF. Patients in permanent AF underwent internal cardioversion that was followed by biatrial temporary pacing for 48 hours. Those who remained in SR received a permanent biatrial pacemaker programmed to a rate responsive mode with a lower rate 90 beats/min. Primary end point of the study included maintenance in SR 3 months after internal cardioversion. Sixteen patients (14 men, 57 ± 11 years) were cardioverted. The median duration of AF was 24 months (quartiles, Q1= 8.5 and Q3= 102) and mean left atrium diameter was 48 ± 04 mm. A permanent biatrial pacemaker was implanted in 11 patients. At a mean follow-up of 15 months (range 4 to 24), 8 patients remained in SR for more than 3 months. AF was eliminated in 5 patients, while in two a second internal cardioversion on amiodarone was required. Antiarrhythmic therapy was used in half of our population and did not predict the long-term maintenance of SR. Following internal cardioversion with continuous biatrial pacing, 50% of patients with permanent AF were maintained for prolonged periods in SR. This is a new modality of treatment of permanent AF directed to the maintenance of SR that provides a further therapeutic option in end-stage AF. [source] Haematopoietic stem cell niche in DrosophilaBIOESSAYS, Issue 8 2007Ute Koch Development and homeostasis of the haematopoietic system is dependent upon stem cells that have the unique ability to both self-renew and to differentiate in all cell lineages of the blood. The crucial decision between haematopoietic stem cell (HSC) self-renewal and differentiation must be tightly controlled. Ultimately, this choice is regulated by the integration of intrinsic signals together with extrinsic cues provided by an exclusive microenvironment, the so-called haematopoietic niche. Although the haematopoietic system of vertebrates has been studied extensively for many decades, the specification of the HSC niche and its signals involved are poorly understood. Much of our current knowledge of how niches regulate long-term maintenance of stem cells is derived from studies on Drosophila germ cells. Now, two recently published studies by Mandal et al.1 and Krezmien et al.2 describe the Drosophila haematopoietic niche and signal transduction pathways that are involved in the maintenance of haematopoietic precursors. Both reports emphasize several features that are important for controlling stem cell behavior and show parallels to both the vertebrate haematopoietic niche as well as the Drosophila germline stem cell niches in ovary and testis. The findings of both papers shed new light on the specific interactions between haematopoietic progenitors and their microenvironment. BioEssays 29:713,716, 2007. © 2007 Wiley Periodicals, Inc. [source] Longevity differs among sexes but is not affected by repeated immune activation in voles (Microtus arvalis)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2009GODEFROY DEVEVEY Investment of resources in immune defences, despite obvious short-term benefits, may be detrimental to long-term maintenance and thus decrease longevity in absence of parasites. In addition, females and males may differ in immune investment and intrinsic longevity because they are subjected to different degrees of sexual competition and extrinsic mortality. In order to test if sex-specific investment in mounting an immune response reduced longevity, we compared the longevity of captive male and female common voles Microtus arvalis regularly challenged with keyhole limpet haemocyanin, an antigen which elicits the production of antibodies, to the longevity of voles injected with the corresponding antigen-free buffer (phosphate-buffered saline). Injections were repeated every 28 days to mimic a chronic infection. The magnitude of immune response did not vary between males and females and did not affect longevity. Overall, females lived longer than males, independently of the immune challenge. Thus, the long-term costs of immunity seem small in voles. The longevity pattern is consistent with the prediction that male-biased predation or parasitism in the wild causes reduced intrinsic lifespan, but this reduction is not mediated by a decrease in male immunity. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 97, 328,333. [source] Current status of metal stents for managing malignant ureteric obstructionBJU INTERNATIONAL, Issue 8 2010Petros Sountoulides Obstruction of the ureters caused by extrinsic compression from a primary tumour or retroperitoneal lymph node masses is not unusual in the course of advanced pelvic malignancies. Most of the cases are of gynaecological or gastrointestinal origin, and the situation can be aggravated by peri-ureteric fibrosis, a long-term adverse event of previous chemotherapy or radiotherapy. Undoubtedly upper urinary tract decompression and maintenance of ureteric patency, even as a palliative measure, is important in managing these patients. Options for upper tract decompression include percutaneous nephrostomy, retrograde stenting and open urinary diversion. Plastic stents have long been used for managing malignant ureteric obstruction, but their overall success remains limited. Plastic stents often fail to be placed correctly, require regular exchange, and are faced with a high incidence of encrustation and migration. For these reasons plastic stents have been unsuccessful for long-term maintenance of ureteric patency. To overcome these limitations metal stents were introduced and recently developed in an effort to ensure better long-term patency of the obstructed ureter, fewer hospital admissions for stent change and better overall quality of life. In the present review the clinical applications of different types of metal stents are discussed, with a specific focus on the latest advances and the future options for managing malignant ureteric obstruction. [source] Pilot intervention to enhance sexual rehabilitation for couples after treatment for localized prostate carcinoma,CANCER, Issue 12 2005Andrea L. Canada Ph.D. Abstract BACKGROUND The majority of prostate carcinoma survivors experience enduring sexual difficulties and associated distress in the years after definitive treatment. A counseling intervention aimed at improving levels of sexual satisfaction and increasing successful utilization of medical treatment for erectile dysfunction (ED) was developed and pilot-tested for both the survivor of prostate carcinoma and his partner. METHODS All male participants were 3-month to 5-year survivors of localized prostate carcinoma who had been treated with radical prostatectomy or radiation therapy, and were married or in a committed relationship. Couples were randomized to attend four sessions of counseling together or to have the man attend alone. In both groups, partners completed behavioral homework. The sessions included education on prostate carcinoma and sexual function and options to treat ED as well as sexual communication and stimulation skills. Standardized questionnaires at baseline, posttreatment, and at 3-month and 6-month follow-up assessed sexual function, marital adjustment, psychologic distress, and utilization of treatments for ED. RESULTS Fifty-one of 84 couples randomized to treatment completed the intervention (61%). Attendance by the partner did not affect outcomes. Participants completing the intervention demonstrated improvment in male overall distress (P < 0.01), male global sexual function (P < 0.0001), and female global sexual function (P < 0.05) at 3-month follow-up, but regression toward baseline was noted at 6-month follow-up. However, utilization of ED treatments increased from 31% at the time of study entry to 49% at the 6-month follow-up (P = 0.003). CONCLUSIONS The results of this brief pilot counseling intervention demonstrated significant gains in sexual function and satisfaction and increased utilization of treatments for ED. However, modifications are needed in future randomized trials to reduce the rate of premature termination and to improve long-term maintenance of gains. Cancer 2005. © 2005 American Cancer Society. [source] Reaffirmation of Behavioral Approaches to Depression TreatmentCLINICAL PSYCHOLOGY: SCIENCE AND PRACTICE, Issue 4 2009Manuel Barrera Jr This meta-analytic review improved on the methods and scope of similar reviews but reached the same conclusion that behavioral activation (BA) therapies for adult depression are much more effective than control conditions and comparable with cognitive-behavioral interventions. Future research should strengthen our understanding of the mechanisms that account for the effectiveness of BA approaches and should provide more evidence on long-term maintenance. The resurgence of interest in BA was attributed to pioneering work of Lewinsohn and the components analysis research of Jacobson and colleagues, who demonstrated the effectiveness of behavioral elements of depression treatment relative to cognitive elements. [source] | |||||||||||||