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BackgroundCampylobacter spp. are one of the commonest causes of diarrhea in children under five and in resource poor settings also lead to malabsorption and stunting. The purpose of this systematic review was to understand the burden of Campylobacter spp. associated diarrhea among children in the South Asian countries.MethodsThis systematic review followed the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analysis) guidelines. Databases were searched with defined keywords for publications from the years 1998–2018. Data on proportion of positive samples was extracted to compare the rates of Campylobacter infection among children (under the age of 19) from different study populations.ResultsOf the 359 publications screened, 27 eligible articles were included in this systematic review and categorized based on study design. In 8 case-control studies, Campylobacter spp. was detected more frequently among diarrheal cases (range, 3.2–17.4%) than non-diarrheal cases (0–13%). Although there were variations in the study population, overall, children under the age of two years experienced Campylobacter diarrhea more often than older children. Most studies reported stool culture as the method used to detect Campylobacter spp. however retesting using PCR-based methods significantly increased detection rates. Limited data were available on Campylobacter species. In 4 studies that provided species data, C. jejuni (3.2–11.2%) was shown to be the most common species, followed by C. coli.ConclusionIn South Asia, Campylobacter spp. are one of the most common bacterial diarrheal pathogens affecting children but there is a paucity of data on species, risk factors and attributable sources. Although a few studies were available, the epidemiology of campylobacteriosis remains uncertain. To understand the true burden and sources of infection, more detailed studies are needed collecting data from human, animal and environmental sources and using both culture and genomic tools.  相似文献   
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Hepatitis C virus infection and lichen planus: a short review   总被引:2,自引:0,他引:2  
OBJECTIVE: To review the current literature regarding the association of lichen planus (LP) and liver disease, with particular attention to the association of the oral variant of the disease with hepatitis C virus (HCV) infection.
MATERIALS AND METHODS: Available literature of the possible association of LP with systemic disorders, in particular chronic hepatic disease, has been reviewed. RESULTS: LP is sometimes associated with infectious or autoimmune disease and/or neoplasia, however an aetio-logical association between LP and these disorders seems unlikely. A more consistent association exists between LP and chronic hepatic disease. The precise cause of this association is not known. However, in the last 6 years a notable association between HCV infection and LP has been observed, particularly in patients in Spain, Italy and Japan. The pathogenesis of this possible HCV-associated LP is not known, but it may involve a cell mediated response to an altered epithelial antigen.
CONCLUSION: There is now evidence to suggest a significant association between HCV infection and LP in some groups of patients.  相似文献   
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OBJECTIVE: Patients may have various forms of angioedema and require dental treatment which can cause or contribute to the onset of an episode of angioedema. This paper seeks to highlight the causes and the management of this serious condition.
DESIGN: An outline of the different types of angioedema is given here, along with three case reports which illustrate treatment and management.
SUBJECTS AND METHODS: Three patients who presented to an Oral Medicine clinic with angioedema are presented to illustrate various types of angioedema and the different contributing factors that precipitated episodes of the condition.
MAIN OUTCOME MEASURES: The three patients were all investigated for biochemical and allergic factors which may have caused their disease.
RESULTS: Both drugs and dental materials were shown to be involved in the pathogenesis of angioedema in this short series of patients.
CONCLUSIONS: Dental treatment or the use of some materials may promote or contribute to the disorder. Referral to hospital for specialist care is indicated for certain groups of patients who require invasive dental treatment. The multi-disciplinary team approach in the investigation and management of patients with angioedema is emphasised.  相似文献   
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In Huntington's disease (HD), increased variability is seen in performance of motor tasks that require implicit control of timing. We examined whether timing variability was also evident in an explicit interval‐timing task. Sixty subjects (21 controls, 19 manifest HD, and 20 pre‐manifest HD) performed a single‐interval production task with three target intervals (1.1 s, 2.2 s, 3.3 s). We analyzed accuracy (proportional error) and precision (standard deviation) across groups and intervals. No differences were seen in accuracy across groups or intervals. Precision was significantly lower in manifest (P = 0.0001) and pre‐manifest HD (P = 0.04) compared with controls. This was particularly true for pre‐manifest subjects close to diagnosis (based on probability of diagnosis in 5 years). Precision was correlated with proximity to diagnosis (r2 = 0.3, P < 0.01). To examine the source of reduced precision, we conducted linear regression of standard deviation with interval duration. Slope of the regression was significantly higher in manifest HD (P = 0.02) and in pre‐manifest HD close to diagnosis (P = 0.04) compared with controls and pre‐manifest participants far from diagnosis. Timing precision is impaired before clinical diagnosis in Huntington's disease. Slope analysis suggests that timing variability (decreased precision) was attributable to deficits in timing‐dependent processes. Our results provide additional support for the proposal that the basal ganglia are implicated in central timekeeping functions. Because the single interval production task was sensitive to deficits in pre‐manifest HD, temporal precision may be a useful outcome measure in future clinical trials. © 2014 International Parkinson and Movement Disorder Society  相似文献   
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Patients with type 2 diabetes demonstrate reduced functional connectivity within the resting state default mode network (DMN), which may signal heightened risk for cognitive decline. In other populations at risk for cognitive decline, additional magnetic resonance imaging abnormalities are evident during task performance, including impaired deactivation of the DMN and reduced activation of task-relevant regions. We investigated whether middle-aged type 2 diabetic patients show these brain activity patterns during encoding and recognition tasks. Compared with control participants, we observed both reduced 1) activation of the dorsolateral prefrontal cortex during encoding and 2) deactivation of the DMN during recognition in type 2 diabetic patients, despite normal cognition. During recognition, activation in several task-relevant regions, including the dorsolateral prefrontal cortex and DMN regions, was positively correlated with HbA1c and insulin resistance, suggesting that these important markers of glucose metabolism impact the brain’s response to a cognitive challenge. Plasma glucose ≥11 mmol/L was associated with impaired deactivation of the DMN, suggesting that acute hyperglycemia contributes to brain abnormalities. Since elderly type 2 diabetic patients often demonstrate cognitive impairments, it is possible that these task-induced brain activity patterns observed in middle age may signal impending cognitive decline.  相似文献   
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In light of the number of studies conducted to examine the treatment of cognitive impairment associated with schizophrenia (CIAS), we critically reviewed recent CIAS trials. Trials were identified through searches of the website “www.clinicaltrials.gov” using the terms “schizophrenia AND cognition,” “schizophrenia AND neurocognition,” “schizophrenia AND neurocognitive tests,” “schizophrenia AND MATRICS,” “schizophrenia AND MCCB,” “schizophrenia AND BACS,” “schizophrenia AND COGSTATE,” and “schizophrenia AND CANTAB” and “first-episode schizophrenia AND cognition.” The cutoff date was 20 April 2011. Included trials were conducted in people with schizophrenia, the effects on cognition were either a primary or secondary outcome, and the effect of a pharmacologically active substance was examined. Drug challenge, pharmacokinetic, pharmacodynamic, or prodrome of psychosis studies were excluded. We identified 118 trials, with 62% using an add-on parallel group design. The large majority of completed trials were underpowered to detect moderate effect sizes, had ≤8 weeks duration, and were performed in samples of participants with chronic stable schizophrenia. The ongoing add-on trials are longer, have larger sample sizes (with a number of them being adequately powered to detect moderate effect sizes), and are more likely to use a widely accepted standardized cognitive battery (eg, the MATRICS Consensus Cognitive Battery) and MATRICS guidelines. Ongoing studies performed in subjects with recent onset schizophrenia may help elucidate which subjects are most likely to show an effect in cognition. New insights into the demands of CIAS trial design and methodology may help increase the probability of identifying treatments with beneficial effect on cognitive impairment in schizophrenia.  相似文献   
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Patients with Parkinson's disease (PD) who carry the G2019S mutation (a glycine to serine substitution at amino acid 2019) in the leucine‐rich repeat kinase 2 (LRRK2) gene are generally believed to be clinically indistinguishable from patients with sporadic PD. There are, however, conflicting reports on the relationship between the mutation and the motor phenotype. We quantitatively compared gait and mobility in patients with PD carriers of the G2019S mutation to non‐carrier patients with PD to better understand the genotype‐phenotype relationship. Fifty patients with PD carriers of the G2019S LRRK2 mutation and 50 age, disease duration, and disease severity matched PD non‐carriers were studied. An accelerometer quantified gait under three walking conditions: usual‐walking, dual‐tasking, and fast‐walking. The Unified Parkinson's Disease Rating Scale classified patients into PD sub‐types and the Timed Up and Go quantified mobility and fall risk. In all three walking conditions, gait variability was larger and the walking pattern was less consistent among the PD mutation carriers (P < 0.016). The PD carriers also took longer to complete the Timed Up and Go (P = 0.011) and were more likely to report having fallen in the previous year (P = 0.018). 64% of the PD carriers were classified as belonging to the postural‐instability‐gait‐difficulty (PIGD) sub‐type compared to only 17% of the PD non‐carriers (P < 0.0001). Among patients with PD, the G2019S mutation in the LRRK2 gene is apparently associated with increased gait variability, an increased fall risk, and the PIGD sub‐type. Therapeutic approach specifically designed to delay gait disturbances and falls may be justified in patients who carry the G2019S mutation. © 2013 International Parkinson and Movement Disorder Society  相似文献   
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