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101.
In rare cases, individuals with a history of long‐term injecting drug use remain seronegative and aviraemic, despite prolonged and likely repeated exposure to Hepatitis C virus (HCV) through high‐risk behaviour. We describe anti‐HCV Envelope (E) antibody responses in a prospective cohort of carefully defined highly exposed but uninfected subjects (HESN) and comparison subjects who were also high risk and uninfected, but rapidly became HCV infected (Incident). Longitudinally collected samples from HESN cases (n = 22) were compared to Incident controls (n = 22). IgG, IgM and IgA from sera were tested by ELISA to genotype 1a and 3a E glycoproteins, and recombinant genotype 1a E2 antigen. IgG subclass isotyping was performed for those positive for IgG. Virus‐neutralizing activity was assessed on HCV pseudoparticles, and HCV E–specific B cells analysed using flow cytometry. A significant minority of HESN cases (n = 10; 45%) had anti‐E, predominantly in the IgG2 subclass, which was not found in the pre‐infection time point of the Incident cases (n = 1; 5%). A subset of the HESN subjects also had neutralizing activity and HCV‐specific B cells detected significantly more than Incident cases pre‐infection. In conclusion, the HESN phenotype is associated with IgG2 anti‐E antibodies, neutralization activity and HCV E–specific memory B cells. These findings suggest that HESN subjects may be resistant to HCV infection through humoral immune‐mediated mechanisms.  相似文献   
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103.
BACKGROUND Percutaneous transluminal angioplasty and stenting represent an effective treatment for hepatic artery stenosis after liver transplantation. In the first year after stenting, approximately 22% of patients experience in-stent restenosis, increasing the risk of artery thrombosis and related complications, and 50% experience liver failure. Although angiography is an important tool for diagnosis and the planning of therapeutic interventions, it may raise doubts, especially in small-diameter arteries, and it provides low resolution rates compared with newer intravascular imaging methods, such as optical coherence tomography(OCT).CASE SUMMARY A 64-year-old male developed hepatic artery stenosis one year after orthotropic liver transplantation and was successfully treated with percutaneous transluminal angioplasty with stenting. Five months later, the Doppler ultrasound results indicated restenosis. Visceral arteriography confirmed hepatic artery tortuosity but was doubtful for significant in-stent restenosis(ISR) and intrahepatic flow reduction. To confirm ISR, identify the etiology and guide treatment, OCT was performed. OCT showed severe stenosis due to four mechanisms: Focal and partial stent fracture, late stent malapposition, in-stent neointimal hyperplasia, and neoatherosclerosis.CONCLUSION Intravascular diagnostic methods can be useful in evaluating cases in which initial angiography results are not sufficient to provide a proper diagnosis of significant stenosis, especially with regard to ISR. A wide range of diagnoses are provided by OCT, resulting in different treatment options. Interventional radiologists should consider intravascular diagnostic methods as additional tools for evaluating patients when visceral angiography results are unclear.  相似文献   
104.
Coinfections with common bacterial respiratory pathogens and influenza viruses are well-known causes of disease, often via synergistic interactions between the influenza virus, the bacteria, and the human host. However, relatively little is known about interactions between atypical bacteria and influenza viruses. A recent report by Reinton et al. explored this issue by analyzing data from 3,661 patients seeking medical assistance for the presence of Mycoplasma pneumoniae, Chlamydophila pneumoniae, and Bordetella pertussis, as well as influenza A or B virus in nasal swab specimens. The report, however, did not accurately assess the epidemiologic interactions of these pathogens. We aimed to describe the interactions between these bacterial species and influenza infections. Strong and highly statistically significant antagonistic interspecies interactions were detected between C. pneumoniae and influenza virus [odds ratio (OR): 0.09; p?M. pneumoniae and influenza virus infections (OR: 0.29; p?=?0.003). No association was detected between B. pertussis and influenza infection (p?=?0.34), contrary to the initial report, and coinfection was not detected at a higher-than-by-chance frequency within the population. Further support of these results is supplied by the analysis of two earlier investigations reporting data on influenza virus and these atypical bacteria. Our results supplement the large body of literature regarding interactions between influenza virus and typical respiratory pathogens, providing a fuller picture of the spectrum of interactions between influenza viruses and respiratory bacteria. Further, we demonstrate the importance of choosing the most appropriate reference populations for the analysis being performed and describe the pitfalls that may occur when care is not taken in this regard.  相似文献   
105.
This study aimed to analyze trends in the 10 leading causes of death in Korea from 1983 to 2012. Death rates were derived from the Korean Statistics Information Service database and age-adjusted to the 2010 population. Joinpoint regression analysis was used to identify the points when statistically significant changes occurred in the trends. Between 1983 and 2012, the age-standardized death rate (ASR) from all causes decreased by 61.6% for men and 51.2% for women. ASRs from malignant neoplasms, diabetes mellitus, and transport accidents increased initially before decreasing. ASRs from hypertensive diseases, heart diseases, cerebrovascular diseases and diseases of the liver showed favorable trends (ASR % change: -94.4%, -53.8%, -76.0%, and -78.9% for men, and -77.1%, -36.5%, -67.8%, and -79.9% for women, respectively). ASRs from pneumonia decreased until the mid-1990s and thereafter increased. ASRs from intentional self-harm increased persistently since around 1990 (ASR % change: 122.0% for men and 217.4% for women). In conclusion, death rates from all causes in Korea decreased significantly in the last three decades except in the late 1990s. Despite the great strides made in the overall mortality, temporal trends varied widely by cause. Mortality trends for malignant neoplasms, diabetes mellitus, pneumonia and intentional self-harm were unfavorable.

Graphical Abstract

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106.
International Journal of Clinical Pharmacy - Background Polypharmacy is a growing health concern for older adults and is associated with poorer clinical outcome. Objective This study aim is to...  相似文献   
107.
108.
The majority of human breast cancers exhibit luminal epithelial differentiation. However, most aggressive behavior, including invasion and purported cancer stem cell activity, are considered characteristics of basal-like cells. We asked the following questions: Must luminal-like breast cancer cells become basal-like to initiate tumors or to invade? Could luminally differentiated cells within a basally initiated hierarchy also be tumorigenic? To answer these questions, we used rare and mutually exclusive lineage markers to isolate subsets of luminal-like and basal-like cells from human breast tumors. We enriched for populations with or without prominent basal-like traits from individual tumors or single cell cloning from cell lines and recovered cells with a luminal-like phenotype. Tumor cells with basal-like traits mimicked phenotypic and functional behavior associated with stem cells assessed by gene expression, mammosphere formation and lineage markers. Luminal-like cells without basal-like traits, surprisingly, were fully capable of initiating invasive tumors in NOD SCID gamma (NSG) mice. In fact, these phenotypically pure luminal-like cells generated larger and more invasive tumors than their basal-like counterparts. The tumorigenicity and invasive potential of the luminal-like cancer cells relied strongly on the expression of the gene GCNT1, which encodes a key glycosyltransferase controlling O-glycan branching. These findings demonstrate that basal-like cells, as defined currently, are not a requirement for breast tumor aggressiveness, and that within a single tumor there are multiple “stem-like” cells with tumorigenic potential casting some doubt on the hypothesis of hierarchical or differentiative loss of tumorigenicity.  相似文献   
109.
Reed RV  Fazel M  Jones L  Panter-Brick C  Stein A 《Lancet》2012,379(9812):250-265
Children and adolescents who are forcibly displaced represent almost half the world's internally displaced and refugee populations. We undertook a two-part systematic search and review of the evidence-base for individual, family, community, and societal risk and protective factors for the mental health outcomes of children and adolescents. Here we review data for displacement to low-income and middle-income settings. We draw together the main findings from reports to identify important issues and establish recommendations for future work. We draw attention to exposure to violence as a well established risk factor for poor mental health. We note the paucity of research into predictor variables other than those in the individual domain and the neglect of other variables for the assessment of causal associations, including potential mediators and moderators identifiable in longitudinal work. We conclude with research and policy recommendations to guide the development and assessment of effective interventions.  相似文献   
110.
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