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Detrimental Consequences (detrimental + consequence)
Selected AbstractsImpact of eucalyptus and pine growing on rural livelihood: the lesson from Bukoba area, north western TanzaniaAFRICAN JOURNAL OF ECOLOGY, Issue 2009Phillip K. MwanukuziArticle first published online: 3 FEB 200 Abstract Sustainable resource management intends to allocate resources in such a way that unnecessary deterioration of biophysical and socio-economical systems is avoided. In Bukoba Area where rainfalls are plenty, evergreen grasslands were expansive and forests were limited, eucalypts (eucalyptus spp.) and pines (pinus spp.) were grown on grasslands for preventing land degradation through deforestation and for providing additional source of income for rural poor. This study shows that in addition to detrimental consequence of eucalyptus and pine forests on soil resources, conversion of Bukoban grasslands to forests has negatively impacted livelihood of the rural poor. Growing eucalypts and pines on grasslands prevented a farming system that enabled integration of grasslands, cattle keeping and crop production. Consequently, the grasslands role of nutrients cycling was disrupted, food crop production reduced, home-gardens productivity declined, majority deprived important livelihood asset and foreign income flow into the area reduced. [source] Refractory Progression of Coronary Aneurysms, a Case of Delayed Onset Kawasaki Disease as Depicted by Cardiac Computed Tomography AngiographyCONGENITAL HEART DISEASE, Issue 3 2010FACP, Shah Azmoon MD ABSTRACT Background., Kawasaki disease (KD) is an immune-mediated vasculitis of unknown etiology with self-limited clinical course that was first described in 1967 by Dr. Tomisaku Kawasaki. It is a disease of early childhood and rare past late adulthood but one that can have detrimental consequences when there is a delay in diagnosis and treatment. Cardiovascular complications causing increased morbidity and mortality may include coronary artery aneurysms, myocardial infarction, heart failure, arrhythmias, and peripheral artery occlusion. Case Presentation., Here, we present an atypical case of delayed onset KD in a young teenager. DS had visited three different emergency departments during the course of 2 weeks for unrelenting fevers. Despite multiple treatment protocols including immunoglobulin, steroids, and tumor necrosis factor-alpha antagonists, he continued to have progression of cardiovascular complications. While echocardiographic findings were suspicious for cardiac complications, a cardiac computed tomography (CT) angiography was able to clearly distinguish giant coronary aneurysms. Conclusion., Without prompt therapy, fever and manifestations of acute inflammation can last for several weeks to months with increased risk toward complications. The incidence of coronary artery aneurysms has been noted to be 25% in untreated patients with a mortality rate of up to 2%. Using low-dose protocols along with high spatial and temporal resolution of cardiac CT angiography may provide a useful and complimentary imaging modality in accurate diagnosis and follow-up of patients with KD. [source] A critical step for postsynaptic F-actin organization: Regulation of Baz/Par-3 localization by aPKC and PTENDEVELOPMENTAL NEUROBIOLOGY, Issue 9 2009Preethi Ramachandran Abstract Actin remodeling has emerged as a critical process during synapse development and plasticity. Thus, understanding the regulatory mechanisms controlling actin organization at synapses is exceedingly important. Here, we used the highly plastic Drosophila neuromuscular junction (NMJ) to understand mechanisms of actin remodeling at postsynaptic sites. Previous studies have suggested that the actin-binding proteins Spectrin and Coracle play a critical role in NMJ development and the anchoring of glutamate receptors most likely through actin regulation. Here, we show that an additional determinant of actin organization at the postsynaptic region is the PDZ protein Baz/Par-3. Decreasing Baz levels in postsynaptic muscles has dramatic consequences for the size of F-actin and spectrin domains at the postsynaptic region. In turn, proper localization of Baz at this site depends on both phosphorylation and dephosphorylation events. Baz phosphorylation by its binding partner, atypical protein kinase C (aPKC), is required for normal Baz targeting to the postsynaptic region. However, the retention of Baz at this site depends on its dephosphorylation mediated by the lipid and protein phosphatase PTEN. Misregulation of the phosphorylation state of Baz by genetic alterations in PTEN or aPKC activity has detrimental consequences for postsynaptic F-actin and spectrin localization, synaptic growth, and receptor localization. Our results provide a novel mechanism of postsynaptic actin regulation through Baz, governed by the antagonistic actions of aPKC and PTEN. Given the conservation of these proteins from worms to mammals, these results are likely to provide new insight into actin organization pathways. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 2009 [source] Implications of species loss in freshwater fish assemblagesECOGRAPHY, Issue 6 2001Anne E. Magurran Freshwater systems are vulnerable to pollution and species loss often ensues. Are there additional implications for assemblage structure? Here we use Berger-Parker d. Simpson's I/D and Simpson's F to measure the ecological diversity of pristine and perturbed freshwater fish assemblages in Trinidad. West Indies, and Oklahoma. USA. Although the impacted sites typically had fewer species than expected, they could not be distinguished from unperturbed ones of equivalent richness. Changes in the evenness of these assemblages are thus driven by changes in richness. One practical outcome is that diversity indices may not provide independent verification of the detrimental consequences of pollution. The similarity in structure of naturally and anthropogenically impoverished assemblages provides no grounds for complacency, however, since it ignores the evolutionary history of the species concerned. On the basis of our results we suggest that species provenance may be important in tests of ecological function. Moreover, these investigations should replicate natural patterns of evenness as well as richness. [source] Expression of the E. coli fpg protein in CHO cells lowers endogenous oxypurine clustered damage levels and decreases accumulation of endogenous Hprt mutations,ENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 5 2006Sunirmal Paul Abstract Endogenous DNA damage clusters,two or more oxidized bases, abasic sites, or strand breaks within about 20 base pairs on opposing strands,can accumulate in unirradiated mammalian cells, and may be significant origins of spontaneous detrimental biological effects. Factors determining the levels of such endogenous clusters are largely unknown. To determine if cellular repair genotype can affect endogenous cluster levels in mammalian cells, the authors examined cluster levels, growth rates, and mutant frequencies in Chinese hamster ovary cells expressing the Escherichia coli glycosylase fpg protein, whose principal substrates are oxidized purines. In cells expressing high levels of fpg protein, the levels of oxypurine clustered damages were decreased while those of oxypyrimidine clusters and abasic clusters were unchanged. Furthermore, in these cells, the growth rates were increased and the level of spontaneous background mutants in the hypoxanthine guanine phosphoribosyl transferase gene was decreased. These results suggest that endogenous clusters are potentially detrimental DNA damages, and that their levels,as well as the detrimental consequences of their presence,can be effectively reduced by increased cellular activity of specific DNA repair proteins. Environ. Mol. Mutagen., 2006. Published 2006 Wiley-Liss, Inc. [source] Paradigm shifts in marine fisheries genetics: ugly hypotheses slain by beautiful factsFISH AND FISHERIES, Issue 4 2008Lorenz Hauser Abstract By providing new approaches to the investigation of demographic and evolutionary dynamics of wild populations, molecular genetics has led to fundamental changes in our understanding of marine ecology. In particular, genetic approaches have revolutionized our understanding in three areas: (i) most importantly, they have contributed to the discovery of extensive genetic population structure in many marine species, overturning the notion of large, essentially homogenous marine populations limiting local adaptation and speciation. (ii) Concomitant differences in ecologically important traits now indicate extensive adaptive differentiation and biocomplexity, potentially increasing the resilience to exploitation and disturbance. Evidence for rapid adaptive change in many populations underlies recent concerns about fisheries-induced evolution affecting life-history traits. (iii) A compilation of recent published research shows estimated effective population sizes that are 2,6 orders of magnitude smaller than census sizes, suggesting more complex recruitment dynamics in marine species than previously assumed. Studies on Atlantic cod are used to illustrate these paradigm shifts. In our synthesis, we emphasize the implications of these discoveries for marine ecology and evolution as well as the management and conservation of exploited marine fish populations. An important implication of genetic structuring and the potential for adaptive divergence is that locally adapted populations are unlikely to be replaced through immigration, with potentially detrimental consequences for the resilience to environmental change , a key consideration for sustainable fisheries management. [source] Increasing intra-abdominal pressure increases pressure, volume, and wall tension in esophageal varicesHEPATOLOGY, Issue 4 2002Angels Escorsell Many daily activities cause acute elevations of intra-abdominal pressure (IAP). In portal hypertensive cirrhotic patients, increased IAP increases absolute portal pressure and azygos blood flow, suggesting that it may have detrimental consequences at the esophageal varices. The aim of this study was to investigate the effects of increased IAP on variceal pressure, size, and wall tension. Endosonography and a noninvasive endoscopic pressure gauge were used to measure variceal pressure, radius, wall tension, and volume in baseline conditions and after increasing IAP by 10 mm Hg using an inflatable girdle in 14 patients with cirrhosis and esophageal varices. Increasing IAP markedly increased variceal pressure (from 13.3 ± 4.2 to 17.4 ± 4.6 mm Hg; P = .0001) and radius (from 2.9 ± 1.0 to 3.9 ± 1.1 mm; P = .0001). Consequently, wall tension dramatically increased (from 38.7 ± 13.6 to 65.9 ± 23.8 mm Hg · mm, +78%; P = .0001). Variceal volume increased significantly from 1,264 ± 759 to 2,025 ± 1,129 mm3 (P = .0001). In conclusion, in portal hypertensive cirrhotic patients, increases in IAP have deleterious effects on variceal hemodynamics, markedly increasing the volume, pressure, and wall tension of the varices. Increases in IAP may contribute to the progressive dilatation that precedes the rupture of the varices in portal hypertension. [source] Back to basics: Learning about employee energy and motivation from running on my treadmillHUMAN RESOURCE MANAGEMENT, Issue 1 2005Theresa M. Welbourne Abstract In an effort to understand how to optimize employee energy at work, we borrow from the sports physiology literature to develop and test several concepts that have now been used in more than 75 large and small organizations (e.g., automobile firms, banks, hospitals, manufacturing, high technology, service businesses, financial services, and more). Our focus on employee energy led us to develop new measures and processes for our research. The resulting studies presented in this article test two hypotheses focusing on the link between employee energy, turnover, job performance, and job satisfaction. Consistent with what we know about athletic performance, we found that energy is an optimization construct and that variation in employee energy at work has detrimental consequences for performance and satisfaction. © 2005 Wiley Periodicals, Inc. [source] Aetiology, diagnosis and treatment of posterior cross-bites in the primary dentitionINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 3 2004M. Malandris Summary., Introduction., Children who present with a posterior cross-bite in the primary dentition may be predisposed to long-term detrimental consequences if the condition is left untreated. Controversy exists in the literature as to the most appropriate time to treat this condition. Objectives., The aim of this review is to evaluate the need for correcting posterior cross-bites in the primary dentition based on the current understanding of the aetiology, likelihood of self-correction, and consequences of various forms of this malocclusion persisting into the mixed and permanent dentitions. A review of the reported treatment options for management of this condition is also presented. Methods., Literature pertaining to the epidemiology and management of posterior cross-bites in the primary dentition are reviewed. Conclusion., Posterior cross-bites in the primary dentition are relatively common and their causes are numerous. Because a significant proportion of posterior cross-bites self-correct beyond the primary dentition, routine correction in the primary dentition phase cannot be advocated. A unilateral posterior cross-bite as a result of a functional displacement of the mandible is one of the few malocclusions which should be considered for correction in the primary dentition. Further research is needed in the management of this condition. [source] Understanding the biodiversity consequences of habitat change: the value of secondary and plantation forests for neotropical dung beetlesJOURNAL OF APPLIED ECOLOGY, Issue 3 2008Toby A. Gardner Summary 1Secondary and plantation forests are becoming increasingly widespread in the tropics. A recent meta-analysis on the impacts of land-use change on tropical forest dung beetles concluded that regenerating forests can be effective in helping to offset species loss following deforestation. However, our understanding of the extent to which these results can be generalized to new locations remains very poor. 2We attempted to overcome many of the design limitations that characterize previous studies by collecting spatially independent dung beetle samples from primary, secondary and Eucalyptus plantation forests in north-east Brazilian Amazonia across a large quasi-experimental landscape that minimized confounding edge and fragmentation effects. 3We recorded 9203 dung beetles, comprising 85 species. Species richness was significantly higher in primary forest and the majority of species were more abundant there than elsewhere, whereas secondary and plantation sites harboured an impoverished subset of primary forest species. 4Our data illustrate the low value of tropical secondary and plantation forests for dung beetles in our study area, and our conclusions are more pessimistic than those of earlier studies. 5Because of differences in the order of species rank-abundance and rank-biomass patterns, re-coding community data from abundance to biomass significantly altered the analytical weight of individual species in determining community patterns. Larger bodied beetles were more prone to local extinctions and abundance declines and this effect was consistent both within and between genera. 6Synthesis and applications. Our study demonstrates that secondary and plantation forests in a large neotropical landscape host exceptionally impoverished dung beetle communities. Furthermore, the depletion of beetle abundance combined with a reduction in average body mass in converted forests is likely to have detrimental consequences for the maintenance of dung beetle-mediated ecosystem services in these habitats. Differences in biogeographical and landscape context, and the influence of common limitations in sampling design, may explain why many other studies have painted a more optimistic picture of the conservation value of anthropogenic habitats. In the absence of further evidence we caution strongly against the claim that forest regeneration schemes on degraded land can effectively offset the loss of species following deforestation, and urge that conservation strategies prioritize the protection of remaining areas of primary forest. [source] Nutrition and diet in the clinical management of multiple sclerosisJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 5 2001A. Payne For many years, medical interest in the relationship between nutrition and multiple sclerosis (MS) has focused largely on aetiology and the influence of dietary fat on the rate and severity of disease. While the cause of MS remains unknown and the influence of dietary fat is unclear, recent studies on antioxidant intake and oxidative stress in MS are strengthening the rationale in support of a healthy eating regime following diagnosis. Dietary intake in MS and the influence of advanced disease on nutritional status are less well researched and documented. Both obesity and malnutrition may occur with detrimental consequences to functional abilities. Cognitive difficulties, dysphagia and the side-effects of drug treatment may further contribute to deterioration in nutritional status. This paper aims to provide a practical overview of dietary management in MS. It reviews the available evidence relating nutrition to MS and discusses dietary management, with particular emphasis on the identification and alleviation of factors affecting nutritional status. [source] Fast, but Error-Prone, Responses During Acute Alcohol Intoxication: Effects of Stimulus-Response Mapping ComplexityALCOHOLISM, Issue 4 2004Tom A. Schweizer Abstract: Background: Although moderate doses of alcohol can impair performance on tasks that require information processing, little is known about the locus of the alcohol effects within the processing stream. This study used a psychological refractory period paradigm to investigate the effect of alcohol on the central, cognitive stage of information processing when task complexity is manipulated by altering stimulus-response compatibility. Methods: Thirty-four healthy male social drinkers were assigned to one of two groups (n= 17) that performed two tasks. Each trial consisted of a task 1 stimulus (tone) followed by a task 2 stimulus (letter) that was presented after one of four stimulus onset asynchronies (50, 200, 500, or 1100 msec). A baseline test of performance was obtained before the groups received a beverage containing either 0.0 g/kg (placebo) or 0.65 g/kg alcohol. Both groups were retested when blood alcohol concentration (BAC) was increasing and was decreasing. Results: The alcohol group made significantly more errors in task 1 compared with their drug-free baseline measure during the ascending phase of the BAC curve, and error rates increased to a greater extent for the more complex arbitrary stimulus-response mapping condition. Moreover, this increase in errors continued unabated during the descending phase of the BAC curve. Increasing BACs also slowed performance (longer reaction time), but unlike errors, reaction time returned to drug-free baseline levels when BAC was decreasing. Conclusions: The results provide evidence that an acute dose of alcohol can impair one aspect of the central, cognitive stages of information processing. The possibility that errors in information processing remain during decreasing BACs even after processing speed has returned to drug-free levels has important practical implications relating to the detrimental consequences of acute alcohol intoxication. [source] Prospective Evaluation of the Balloon-to-Annulus Ratio for Valvuloplasty in the Treatment of Pulmonic Stenosis in the DogJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 4 2006Amara Estrada Background: In dogs, treatment of pulmonic valve stenosis (PS) with pulmonary balloon valvuloplasty (PBV) is a viable method to decrease the pressure gradient across the valve. However, to the authors' knowledge, the variables that influence the selection of the correct balloon size for the procedure have not been explored. Moreover, the lesions caused by the procedure have not been detailed. Hypothesis: Variables that influence the measurement of the annulus could affect selection of the balloon size. We sought to determine the effects of treatment when the balloon-to-annulus ratio (BAR) was or > 1.3, but within the recommended range of 1.2,1.5, regardless of whether dilation was performed with single or double balloon technique. Animals: Twenty-five Beagles with PS were studied. Methods: Inter-and intra-observer variability, echocardiography versus angiocardiography, and systolic versus diastolic timing were evaluated for the BAR. Assessment of right ventricular (RV) pressure, Doppler gradient, stenotic valve area, and RV wall thickness were compared before and 1, 90, and 180 days after treatment. Postmortem examination of the heart was done. Results: Significant correlations existed in measurement of the annulus; however, variation existed that would change balloon size. Improvement in the degree of PS was significant regardless of the BAR or single or double ballooning. In the most severely affected dogs, continued improvement was noted on day 90. Postmortem examination revealed tears in the commissures and the valve leaflets. Conclusions: Multiple factors influenced determination of the BAR and a range of 1.2,1.5 was effective without detrimental consequences. Dogs with severe PS had continued decrease in RV pressure 3 months after treatment. [source] Immune effect of hypertonic saline: fact or fiction?ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 6 2004J. A. Kølsen-Petersen Hypertonicity affects many parts of the immune system. Animal studies and experiments in isolated cell cultures show that hypertonicity reversibly suppresses several neutrophil functions and at the same time up-regulates T-lymphocyte function. Infusion of hypertonic saline with or without colloids may thus, besides providing efficient plasma volume expansion, ameliorate the detrimental consequences on the immune function of trauma, shock, reperfusion, and major surgery. However, the few clinical studies conducted to date, specifically addressing the immune effect of hypertonic saline infusion, have shown little, if any, effect on markers of immune function, and larger clinical trials have not demonstrated benefit in terms of morbidity or mortality. Thus, as opposed to animal and cell-culture studies, the immune-modulating properties of hypertonic saline infusion would appear to be of limited value in clinical practice. This review presents in vitro studies, animal experiments, and clinical trials which investigated the consequences of hypertonic saline on markers of immune function. [source] Paracetamol use in musculoskeletal pain: an audit of use and patient perceptions of paracetamol as an effective analgesicMUSCULOSKELETAL CARE, Issue 4 2005Emma J Boger RGN BSc(Hons) DipHE Nurse Researcher Abstract Musculoskeletal pain is a complex problem with often very detrimental consequences which affects a high proportion of the general population. Health care professionals, when prescribing for musculoskeletal pain, often overlook simple analgesia. Patient perceptions of analgesia may vary to those of health care professionals, and in part affect the use of simple analgesia for musculoskeletal pain. This paper describes an audit of paracetamol use and patient perceptions of paracetamol as an effective analgesic agent, in 113 patients attending a musculoskeletal pain outpatient clinic in a university teaching hospital. The audit has helped prompt the development of a multi-disciplinary strategy to achieve optimum management. Copyright © 2005 John Wiley & Sons, Ltd. [source] Dietary factors in the aetiology of postnatal depressionNUTRITION BULLETIN, Issue 3 2008E. Derbyshire Summary Prevalence of postnatal depression (PND) occurs in approximately 13,20% of women after birth and has detrimental consequences for both the mother and the offspring. The causes of PND remain unclear, with research suggesting a multifactorial aetiology. It is believed that some dietary constituents may, in part, be related to the onset of PND. The possible protective roles of folate, riboflavin, calcium, magnesium and zinc intake have been investigated, as well as the role of a high glycaemic index diet, with conflicting results. Most of the literature appears to have focused on the symptoms of PND in relation to patterns of fish consumption and intake of n -3(omega-3) fatty acids. A review of studies published through MEDLINE indicated that riboflavin, calcium and zinc may play a role in alleviating symptoms of PND. Although a greater number of published papers have studied associations between n -3 intake and PND incidence, findings are somewhat contradictory. Further research is now required to develop these preliminary research findings with an aim to reducing the health costs of PND through the application of nutritional interventions. [source] Loyal but ignored: The benefits and costs of constructive communication behaviorPERSONAL RELATIONSHIPS, Issue 1 2010NICKOLA C. OVERALL The consequences of exit, voice, loyalty, and neglect behavior were examined using retrospective questionnaires (Study 1) and 2 social interaction diary studies (Study 2). Exit and neglect were generally associated with more negative partner responses and reduced feelings of value and closeness, and were reported to be more harmful to the relationship. Voice was associated with more positive partner responses and greater value and intimacy, and was perceived to be most beneficial to the relationship. In contrast, loyalty was perceived to have the same detrimental consequences as destructive behaviors (Study 1) and did not predict more positive outcomes within daily interactions (Study 2). These results indicate that, despite good intentions, loyal intimates are often left feeling ignored and unappreciated. [source] The ,Indirect' Effects of Cytomegalovirus InfectionAMERICAN JOURNAL OF TRANSPLANTATION, Issue 11 2009R. B. Freeman Cytomegalovirus (CMV) remains the most important infection in the immunocompromized host even in the era of effective therapy. CMV is usually acquired early in life and can be transmitted by contact with infected body fluids. In the immunocompetent population, primary infection is almost always of little clinical consequence. However, CMV infection in immunocompromized patients, especially those naive to CMV exposure, can cause tissue invasive disease, severe symptoms and/or death. However, beyond these direct effects, increasing in vitro evidence is accumulating that suggests CMV has many other effects on the host's immune response which may explain some of the detrimental consequences for the immunosuppressed patient, and may also be partially responsible for a variety of conditions in immunocompetent individuals. In its latent state, CMV employs several mechanisms to evade detection by the host's immune system. The virus also employs other methods to take advantage of activation of the immune system and replicate in sites of inflammation. This review focuses on the immunosuppressive and inflammatory mechanisms that have been attributed to CMV and will relate them to some of the clinical sequellae that have been associated with the indirect effects of CMV infection. [source] Pre-operative vitamin B infusion and prevention of nitrous oxide-induced homocysteine increaseANAESTHESIA, Issue 7 2010L. K. Rao Summary Nitrous oxide inactivates vitamin B12 with detrimental consequences for folate and methionine metabolism, detectable by an increase in total plasma homocysteine. We hypothesised that a pre-operative vitamin B12 and folate infusion prevents nitrous oxide-induced homocysteine increase. Sixty-three healthy patients having elective surgery were randomly allocated to receive either B-vitamin plus nitrous oxide; placebo plus nitrous oxide or placebo plus air. Fifty-nine patients completed the study. After intravenous B-vitamin infusion, plasma vitamin B12 and folate concentrations increased 35-fold and 12-fold, respectively, on the first postoperative measurement. Patients who received B-vitamins developed a similar increase (18%) in homocysteine after nitrous oxide (1.9 ,mol.l,1; 95% CI 0.2,3.6 ,mol.l,1) as those who did not (22%; 2.7 ,mol.l,1; 95% CI 0.6,4.8 ,mol.l,1). Patients not receiving nitrous oxide had no homocysteine change (0.5 ,mol.l,1; 95% CI ,0.8,1.9 ,mol.l,1), indicating that pre-operative intravenous B-vitamins may not prevent nitrous oxide-induced hyperhomocysteinaemia. [source] Orthopaedic-geriatric models of care and their effectivenessAUSTRALASIAN JOURNAL ON AGEING, Issue 4 2009Carol P Chong Different types of orthopaedic geriatric units have been established. This review evaluates the effectiveness of this model of care. A computerised literature search was undertaken using Medline (January 1966,February 2009), Cochrane and CINAHL with the search terms orthopaedics, geriatrics, aged, orthopaedic procedures and fractures. Relevant articles were evaluated and appraised with particular focus on randomised controlled trials. Orthopaedic-geriatric models can be divided according to the setting of care (i) acute inpatient orthopaedic-geriatric care; (ii) subacute rehabilitation; and (iii) community-based rehabilitation. Studies have been heterogenous in nature and outcomes measured have differed making pooled data analysis difficult. In general, there is a trend to effectiveness in outcomes such as functional recovery, length of stay, complications and mortality and importantly studies have not shown detrimental consequences. However, because of the varied types of interventions and models of care, it is difficult to draw firm conclusions about the effectiveness of these programs. [source] CD8 T cell responses to viral infections in sequenceCELLULAR MICROBIOLOGY, Issue 5 2004Michael A. Brehm Summary Our current understanding of virus-specific T cell responses has been shaped by model systems with mice, where naive animals are infected with a single viral pathogen. Paradigms derived from such models, however, may not always be applicable to a natural setting, where a host is exposed to numerous pathogens over its lifetime. Accumulating data in animal models and with some human diseases indicate that a host's prior history of infections can impact the specificity of future CD8 T cell responses, even to unrelated viruses. This can have both beneficial and detrimental consequences for the host, including altered clearance of virus, distinct forms of immunopathology, and substantial changes in the pool of memory T cells. Here we will describe the characteristics of CD8 T cells and the dynamics of their response to heterologous viral infections in sequence. [source] | |||||||||||||||||||||||||