The appearance of eight new respiratory viruses, including the SARS coronavirus in 2003 and swine-origin influenza A/H1N1 in 2009, in the human population in the past nine years has tested the ...ability of virology laboratories to develop diagnostic tests to identify these viruses. Nucleic acid based amplification tests (NATs) for respiratory viruses were first introduced two decades ago and today are utilized for the detection of both conventional and emerging viruses. These tests are more sensitive than other diagnostic approaches, including virus isolation in cell culture, shell vial culture (SVC), antigen detection by direct fluorescent antibody (DFA) staining, and rapid enzyme immunoassay (EIA), and now form the backbone of clinical virology laboratory testing around the world. NATs not only provide fast, accurate and sensitive detection of respiratory viruses in clinical specimens but also have increased our understanding of the epidemiology of both new emerging viruses such as the pandemic H1N1 influenza virus of 2009, and conventional viruses such as the common cold viruses, including rhinovirus and coronavirus. Multiplex polymerase chain reaction (PCR) assays introduced in the last five years detect up to 19 different viruses in a single test. Several multiplex PCR tests are now commercially available and tests are working their way into clinical laboratories. The final chapter in the evolution of respiratory virus diagnostics has been the addition of allelic discrimination and detection of single nucleotide polymorphisms associated with antiviral resistance. These assays are now being multiplexed with primary detection and subtyping assays, especially in the case of influenza virus. These resistance assays, together with viral load assays, will enable clinical laboratories to provide physicians with new and important information for optimal treatment of respiratory virus infections.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK, VSZLJ
To assess anal oncogenic human papillomavirus (HPV) and anal cytology as screening tests for detecting high-grade anal intraepithelial neoplasia (AIN 2+), as this is an immediate anal cancer ...precursor.
Cross-sectional study of 401 HIV-positive men who have sex with men (MSM). The endpoint was histologically confirmed AIN 2+ obtained by high-resolution anoscopy. Cytology and biopsy specimens were assigned random numbers and independently assessed by two pathologists.
We did concomitant anal cytology, anal HPV testing and HRA with directed biopsies without knowing the results of each intervention. The main outcome measures were the sensitivity, specificity, negative predictive value and positive predictive value of anal cytology and oncogenic HPV for the detection of AIN 2+.
Cytology was abnormal in 67% of patients: high-grade squamous intraepithelial lesion, 12%; low-grade squamous intraepithelial lesion, 43% and atypical squamous cells of undetermined significance, 12%. Biopsies were abnormal in 68% of patients: AIN 2+, 25% and AIN 1, 43%. HPV was detected in 93% with multiple HPV types in 92% and oncogenic HPV types in 88%. Test performance characteristics for the detection of AIN 2+ using any abnormality on anal cytology were: sensitivity 84%, specificity 39%, negative predictive value 88% and positive predictive value 31%; using oncogenic HPV: sensitivity 100%, specificity 16%, negative predictive value 100% and positive predictive value 28%.
Anal cytology and HPV detection have high sensitivity but low specificity for detecting AIN 2+. HIV-positive men who have sex with men have a high prevalence of AIN 2+ and require high-resolution anoscopy for optimal detection of high-grade anal dysplasia.
The appearance of eight new respiratory viruses in the human population in the past 9 years, including two new pandemics (SARS coronavirus in 2003 and swine-origin influenza A/H1N1 in 2009), has ...tested the ability of virology laboratories to develop diagnostic tests to identify these viruses. Nucleic acid amplification tests (NATs) that first appeared two decades ago have been developed for both conventional and emerging viruses and now form the backbone of the clincical laboratory. NATs provide fast, accurate and sensitive detection of respiratory viruses and have significantly increased our understanding of the epidemiology of these viruses. Multiplex PCR assays have been introduced recently and several commercial tests are now available. The final chapter in the evolution of respiratory virus diagnostics will be the addition of allelic discrimination and detection of single nucleotide polymorphisms associated with antiviral resistance to multiplex assays. These resistance assays together with new viral load tests will enable clinical laboratories to provide physicians with important information for optimal treatment of patients.
An appropriate means of quantitating infectious Chlamydia from infected animals is essential for the evaluation of vaccines. However, unlike methods involving culture, nonculture methods, including ...detection of antigen or DNA, are not able to differentiate between viable and nonviable organisms. As an obligate intracellular bacterium, Chlamydia replicates inside host cells by forming unique organelles called inclusions. Here, we describe the enumeration of viable C. trachomatis from infected mice by culturing vaginal swabs on McCoy cells and counting inclusions via immunofluorescent microscopy.
Chronic obstructive pulmonary disease (COPD) and influenza virus infections are major global health issues. Patients with COPD are more susceptible to infection, which exacerbates their condition and ...increases morbidity and mortality. The mechanisms of increased susceptibility remain poorly understood, and current preventions and treatments have substantial limitations.
To characterize the mechanisms of increased susceptibility to influenza virus infection in COPD and the potential for therapeutic targeting.
We used a combination of primary bronchial epithelial cells (pBECs) from COPD and healthy control subjects, a mouse model of cigarette smoke-induced experimental COPD, and influenza infection. The role of the phosphoinositide-3-kinase (PI3K) pathway was characterized using molecular methods, and its potential for targeting assessed using inhibitors.
COPD pBECs were susceptible to increased viral entry and replication. Infected mice with experimental COPD also had more severe infection (increased viral titer and pulmonary inflammation, and compromised lung function). These processes were associated with impaired antiviral immunity, reduced retinoic acid-inducible gene-I, and IFN/cytokine and chemokine responses. Increased PI3K-p110α levels and activity in COPD pBECs and/or mice were responsible for increased infection and reduced antiviral responses. Global PI3K, specific therapeutic p110α inhibitors, or exogenous IFN-β restored protective antiviral responses, suppressed infection, and improved lung function.
The increased susceptibility of individuals with COPD to influenza likely results from impaired antiviral responses, which are mediated by increased PI3K-p110α activity. This pathway may be targeted therapeutically in COPD, or in healthy individuals, during seasonal or pandemic outbreaks to prevent and/or treat influenza.
We performed a cost analysis study using decision tree modeling to determine whether the use of multiplex PCR testing for respiratory viruses (xTAG RVP test) is a more or less costly strategy than ...the status quo testing methods used for the diagnosis of respiratory virus infections in pediatric patients. The decision tree model was constructed by using four testing strategies for respiratory virus detection, viz., direct fluorescent-antibody staining (DFA) alone, DFA plus shell vial culture (SVC), the xTAG RVP test alone, or DFA plus the xTAG RVP test. A review of the charts of 661 pediatric patients was used to determine the length of hospital stay, the number of days in isolation, antibiotic usage, and all other medical procedures performed. The cost of hospitalization by diagnostic status was determined on the basis of the average cost per patient and the number of patients in each arm of the decision tree. The cost per case was the highest for DFA plus SVC at $3,914 (in Canadian dollars), and the lowest was for the xTAG RVP test alone at $3,623, while the costs of DFA alone ($3,911) and DFA plus RVP ($3,849) were intermediate. When all four diagnostic strategies were compared, the least costly strategy was the xTAG RVP test alone when the prevalence of infection was 11% or higher and DFA alone when the prevalence was under 11%. These data indicate a savings of $291 per case investigated if the strategy of using the xTAG RVP test alone was used to replace the status quo test of DFA plus SVC, resulting in a savings of $529,620 per year in direct costs for the four Hamilton, Ontario, Canada, hospitals on the basis of the testing of specimens from 1,820 pediatric inpatients. We conclude that the use of the xTAG RVP test is the least costly strategy for the diagnosis of respiratory virus infections in children and would generate a significant savings for hospitals.
Volcanic eruptions are the dominant cause of natural variability in climate forcing on timescales up to multidecadal. Large volcanic eruptions lead to global-scale climate effects and influence the ...carbon cycle on long timescales. However, estimating the frequency of eruptions is challenging. Here we assess the frequency at which eruptions with particular deposition fluxes are observed in the EPICA Dome C ice core over the last
200 kyr. Using S isotope analysis we confirm that most of the largest peaks recorded at Dome C are from stratospheric eruptions. The cumulative
frequency through 200 kyr is close to linear, suggesting an approximately
constant rate of eruptions. There is no evidence for an increase in the rate of events recorded in Antarctica at either of the last two deglaciations. Millennial variability is at the level expected from recording small numbers of eruptions, while multimillennial variability may be partly due to changes in transport efficiency through the Brewer–Dobson circulation. Our record of events with sulfate deposition rates > 20 and >50 mg m−2 contains 678 and 75 eruptions, respectively, over the last 200 kyr. Calibration with data on historic eruptions and analysis of a global Quaternary dataset of terrestrial eruptions indicates that sulfate peaks with deposition rates > 20 and >50 mg m−2 correspond to explosive eruptions of magnitude ≥ 6.5 and ≥7, respectively. The largest recorded eruption deposited just over 300 mg m−2.
Abstract Chlamydia trachomatis infections in women are often asymptomatic and if left untreated can lead to significant late sequelae including pelvic inflammatory disease and tubal factor ...infertility. Vaccine development efforts over the past three decades have been unproductive and there is no vaccine approved for use in humans. The existence of serologically distinct strains or serovars of C. trachomatis mandates a vaccine that will provide protection against multiple serovars. Chlamydia spp. use a highly conserved type III secretion system (T3SS) composed of both structural and effector proteins which is an essential virulence factor for infection and intracellular replication. In this study we evaluated a novel fusion protein antigen (BD584) which consists of three T3SS proteins from C. trachomatis (CopB, CopD, and CT584) as a potential chlamydial vaccine candidate. Intranasal immunization with BD584 elicited serum neutralizing antibodies that inhibited C. trachomatis infection in vitro . Following intravaginal challenge with C. muridarum , immunized mice had a 95% reduction in chlamydial shedding from the vagina at the peak of infection and cleared the infection sooner than control mice. Immunization with BD584 also reduced the rate of hydrosalpinx by 87.5% compared to control mice. Together, these results suggest that highly conserved proteins of the chlamydial T3SS may represent good candidates for a Chlamydia vaccine.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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