bluuebunny/crossref_metadata_2025_split huggingface dataset:
When Should a Patient Receive an Arteriovenous Graft Rather Than a Fistula?
Authors: Lee Ho‐Won , Allon Michael 
Published: November 2012

AbstractThere has been a dramatic increase in the placement and use of arteriovenous fistulas (AVF) in US patients with chronic kidney disease over the past few years, in accordance with strong recommendations by Fistula First Initiative and KDOQI guidelines. However, AVF nonmaturation remains a substantial obstacle to achieving functional AVFs in a subset of patients, despite the widespread use of preoperative vascular mapping to assist surgeons in planning access surgery, and the growing use of interventions to salvage nonmaturing AVFs. In the right patient, aggressive efforts result in a functioning AVF, which provides adequate dialysis with relatively few interventions required to maintain its long‐term patency for dialysis. In the wrong patient, aggressive efforts to achieve a mature AVF may result in numerous failed surgical and percutaneous procedures and prolonged catheter dependence, with all its associated complications. Thus, strict recommendations to place an AVF in all dialysis patients might not benefit every patient, and may actually harm some patients. There are no randomized clinical trials to address which patients are more suitable for placement of an arteriovenous graft (AVG), rather than an AVF. However, there is a wealth of observational studies, which taken cumulatively, may assist clinicians in identifying those patients who should receive an AVG. In this article, we review the relevant published literature regarding this topic and provide suggestions for stratifying patients who should receive each type of vascular access.
Transradial Approach for Cardiovascular Interventions and Its Implications for Hemodialysis Vascular Access
Authors: Wang Shouwen , Asif Arif 
Published: November 2012

AbstractBecause of its advantages, the transradial approach for cardiovascular interventions has gained significant popularity. However, this approach can be associated with radial artery thrombosis and occlusion. The complication generates a major concern for its potential impact on the future creation of an arteriovenous hemodialysis access. The issue gains more importance as a significant number of patients with cardiovascular disease suffer from underlying chronic kidney disease (CKD) and might need an arteriovenous access for hemodialysis therapy. In this context, the preservation of the arterial system is of equal importance to the frequently highlighted venous conservation for the successful creation of an arteriovenous access. It is for this reason that the Fistula First Breakthrough Initiative recommends avoiding the use of the radial artery for performing percutaneous interventions in patients with advanced CKD. Furthermore, there is scarce clinical data and publication regarding the impact of transradial approach on hemodialysis access. Is it possible to utilize the potential benefits and minimize the potential risks of transradial approach in chronic kidney disease patients? On the basis of current knowledge, this review discusses related issues of transradial approach to raise awareness and understanding, which are essential to proper caring of CKD patients undergoing cardiovascular interventions.
Cost analysis in favor of a combined approach for cytomegalovirus after kidney transplantation: a single‐center experience
Authors: Hellemans R. , Beutels P. , Ieven M. , Verpooten G.A. , Bosmans J.L. 
Published: November 2012

AbstractBackgroundIn kidney transplant recipients, cytomegalovirus (CMV) can cause significant morbidity, mortality, and costs, which can be prevented by universal antiviral prophylaxis or preemptive therapy.MethodsWith the aim to improve our understanding of the advantages and disadvantages of these interventions, we documented resource use for 101 consecutive kidney transplant recipients in our center receiving preemptive therapy and estimated resource use for 2 alternative scenarios.ResultsAt 100 days after transplantation, the mean total costs of our preemptive strategy including monitoring and treatment with intravenous ganciclovir was €2545 per patient. At €4853 per patient, these costs were highest for the CMV‐positive donor/CMV‐negative recipient (D+/R−) patient subgroup (n = 28), who frequently require recurrent treatment. A treatment scenario with valganciclovir prophylaxis for D+/R− and R+ patients, in which we ignored late‐onset disease after discontinuation of prophylaxis, resulted in an estimated cost of €1892 per patient. A combined approach using valganciclovir prophylaxis in the D+/R− group and a preemptive strategy in the R+ groups would result in the lowest mean and median costs per patient (€1701).ConclusionOur study suggests that a combined approach, using valganciclovir prophylaxis in D+/R− patients and preemptive treatment in R+ patients, may result in the lowest cost. This approach seems reasonable as it restricts expensive prophylactic drug therapy to those who would benefit the most, whereas it limits the risk for drug toxicity and late‐onset disease in those at lower risk for CMV.
Vancomycin‐resistant enterococcal meningitis in an autologous stem cell transplant recipient cured with linezolid
Authors: Frasca K.L. , Schuster M.G. 
Published: November 2012

AbstractEnterococci are an unusual cause of meningitis, with most cases reported in the literature preceded by neurosurgical procedures. Spread to the meninges from an enterococcal bloodstream infection is even more rare, with few cases reported in the literature. We report the first documented case, to our knowledge, of successful treatment of vancomycin‐resistant enterococcal (VRE) meningitis with linezolid therapy in an immunosuppressed hematopoietic stem cell transplant recipient. Our case highlights the success of monotherapy with linezolid for VRE meningitis. A literature review is provided, which reveals that there is little evidenced‐based data on the optimal therapy for VRE meningitis.
C2‐mediated decrease in DNA methylation, accumulation of siRNAs, and increase in expression for genes involved in defense pathways in plants infected with beet severe curly top virus
Authors: Yang Li‐Ping , Fang Yuan‐Yuan , An Chun‐Peng , Dong Li , Zhang Zhong‐Hui , Chen Hao , Xie Qi , Guo Hui‐Shan 
Published: November 2012

SummaryCytosine methylation is one of epigenetic information marked on the DNA sequence. In plants, small interfering RNAs (siRNAs) target homologous genomic DNA sequences for cytosine methylation. This process, known as RNA‐directed DNA methylation (RdDM), plays an important role in transposon control, regulation of gene expression and virus resistance. In this paper, we demonstrate that the C2 protein encoded by a geminivirus (beet severe curly top virus, BSCTV) mediated a decrease in DNA methylation of repeat regions in the promoters of ACD6, an upstream regulator of the salicylic acid defense pathway, and GSTF14, an endogenous gene of the glutathione S‐transferase superfamily that is implicated in numerous stress responses. C2‐mediated decreases in DNA methylation reduced accumulation of the siRNAs derived from the promoter repeats and enhanced the steady‐state expression of both ACD6 and GSTF14 transcripts. Reduced accumulation of BSCTV‐derived siRNAs was detected in BSCTV‐infected plants, but not in plants infected with C2‐deficient BSCTV (c2− BSCTV). C2 protein exhibited no siRNA‐binding activity. Instead, our results revealed that C2 protein‐mediated decreases in DNA methylation appeared to affect the production of siRNAs that are required for targeting and reinforcing RdDM, a process that activated expression of defense‐related genes that are normally dampened by these siRNAs in the host plants. However, C2‐dependent reduction in virus‐derived siRNAs also benefits the viruses by disrupting the feedback loop reinforcing DNA methylation‐mediated antiviral silencing.
On the Efficacy and Safety of Vaccination with Live Tachyzoites of Neospora caninum for Prevention of Neospora-Associated Fetal Loss in Cattle
Authors: Weber Fred H. , Jackson James A. , Sobecki Brian , Choromanski Les , Olsen Mary , Meinert Todd , Frank Rodney , Reichel Michael P. , Ellis John T. 
Published: November 2012

ABSTRACTInfection of cattle withNeospora caninummay result in abortion or the birth of a congenitally infected calf. Vaccination with liveN. caninumprotects against experimental infection of cattle and mice, and the naturally attenuated Nc-Nowra strain ofN. caninumis of particular interest as a potential vaccine candidate. Vaccination of heifers prior to breeding with live Nc-Nowra tachyzoites by either the subcutaneous or the intravenous route reduced the rate of abortion and the presence of the parasite in calves as determined by PCR and serology after infection of cows with a virulent isolate. Protected fractions were 55.6% to 85.2% depending on the route of vaccination and growth conditions of the vaccine strain, with cryopreserved Nc-Nowra tachyzoites being less effective, with a 25.9% protected fraction. Vaccination appeared to reduce the rate of pregnancy after artificial insemination in some groups compared to nonvaccinated, nonchallenged controls. One animal that was vaccinated but not challenged experienced an abortion, but Nc-Nowra could not be detected in any of the cows in this group or their progeny. This study confirms that live vaccination can be an effective method of preventing neosporosis in cattle and yet highlights the technical hurdle of preservation of live parasites that must be overcome for a vaccine to be commercially successful.
Incidence Rates of Clinical Mastitis among Canadian Holsteins Classified as High, Average, or Low Immune Responders
Authors: Thompson-Crispi Kathleen A. , Miglior Filippo , Mallard Bonnie A. 
Published: November 2012

ABSTRACT
The objective of this study was to compare the incidence rate of clinical mastitis (IRCM) between cows classified as high, average, or low for antibody-mediated immune responses (AMIR) and cell-mediated immune responses (CMIR). In collaboration with the Canadian Bovine Mastitis Research Network, 458 lactating Holsteins from 41 herds were immunized with a type 1 and a type 2 test antigen to stimulate adaptive immune responses. A delayed-type hypersensitivity test to the type 1 test antigen was used as an indicator of CMIR, and serum antibody of the IgG1 isotype to the type 2 test antigen was used for AMIR determination. By using estimated breeding values for these traits, cows were classified as high, average, or low responders. The IRCM was calculated as the number of cases of mastitis experienced over the total time at risk throughout the 2-year study period. High-AMIR cows had an IRCM of 17.1 cases per 100 cow-years, which was significantly lower than average and low responders, with 27.9 and 30.7 cases per 100 cow-years, respectively. Low-AMIR cows tended to have the most severe mastitis. No differences in the IRCM were noted when cows were classified based on CMIR, likely due to the extracellular nature of mastitis-causing pathogens. The results of this study demonstrate the desirability of breeding dairy cattle for enhanced immune responses to decrease the incidence and severity of mastitis in the Canadian dairy industry.
Factors Influencing the Sensitivity and Specificity of Conventional Sequencing in Human Immunodeficiency Virus Type 1 Tropism Testing
Authors: Knapp David J. H. F. , McGovern Rachel A. , Dong Winnie , Poon Art F. Y. , Swenson Luke C. , Zhong Xiaoyin , Woods Conan K. , Harrigan P. Richard 
Published: November 2012

ABSTRACTHuman immunodeficiency virus type 1 (HIV-1) V3 loop sequence can be used to infer viral coreceptor use. The effect of input copy number on population-based sequencing of the V3 loop of HIV-1 was examined through replicate deep and population-based sequencing of samples with known tropism, a heterogeneous clinical sample (624 population-based sequences and 47 deep-sequencing replicates), and a large cohort of clinical samples from phase III clinical trials of maraviroc including the MOTIVATE/A4001029 studies (n= 1,521). Proviral DNA from two independent samples from each of 101 patients from the MOTIVATE/A4001029 studies was also analyzed. Cumulative technical error occurred at a rate of 3 × 10−4mismatches/bp, without observed effect on inferred tropism. Increasing PCR replication increased minority species detection with an ∼10% minority population detected in 18% of cases using a single replicate at a viral load of 1,072 copies/ml and in 44% of cases using three replicates. The nucleotide prevalence detected by population-based and deep sequencing were highly correlated (Spearman's ρ, 0.73), and the accuracy increased with increasing input copy number (P< 0.001). Triplicate sequencing was able to predict tropism changes in the MOTIVATE/A4001029 studies for both low (P= 0.05) and high (P= 0.02) viral loads. Sequences derived from independently extracted and processed samples of proviral DNA for the same patient were equivalent to replicates from the same extraction (P= 0.45) and had correlated position-specific scoring matrix scores (Spearman's ρ, 0.75;P≪ 0.001); however, concordance in tropism inference was only 83%. Input copy number and PCR replication are important factors in minority species detection in samples with significant heterogeneity.
Optimization of a Combined Human Parechovirus-Enterovirus Real-Time Reverse Transcription-PCR Assay and Evaluation of a New Parechovirus 3-Specific Assay for Cerebrospinal Fluid Specimen Testing
Authors: Selvaraju Suresh B. , Nix W. Allan , Oberste M. Steven , Selvarangan Rangaraj 
Published: November 2012

ABSTRACT

Human parechoviruses (HPeVs), particularly type 3 (HPeV3), are known central nervous system (CNS) pathogens, causing serious infections in infants similar to those caused by enteroviruses (EVs). The primary aim of this study was to combine and validate HPeV and EV real-time reverse transcription-PCR (RT-PCR) detection assays with the best available RT-PCR reagents and conditions for parallel detection of HPeV and EV on a single platform. The secondary aim was to develop and validate a newly developed HPeV3-specific real-time RT-PCR assay. Five commercially available RT-PCR kits were evaluated with the pan-HPeV and EV assays in one-step and two-step RT-PCRs. Two-step RT-PCR with the AgPath ID RT-PCR (AGP) kit performed best for both pan-HPeV and EV assays. The pan-HPeV-specific assay performed best with the AGP kit in a one-step RT-PCR. Frozen aliquots of 145 (for HPeV,
n
= 70; for EV,
n
= 75) previously characterized cerebrospinal fluid (CSF) specimens were tested by EV-, pan-HPeV-, and HPeV3-specific (HPeV specimens only) assays. The pan-HPeV and EV assays demonstrated 100% analytical sensitivity and specificity compared to historic results, while the HPeV3-specific assay demonstrated 97% sensitivity and 100% specificity. We propose a real-time pan-HPeV, EV two-step RT-PCR algorithm for simultaneous detection of HPeV and EV from CSF specimens on a single platform. The HPeV3-specific one-step RT-PCR assay can be used as a rapid and cost-effective assay to detect and identify HPeV3 in pan-HPeV RT-PCR assay-positive CSF specimens.
Simultaneous Detection, Genotyping, and Quantification of Human Papillomaviruses by Multicolor Real-Time PCR and Melting Curve Analysis
Authors: Liao Yiqun , Zhou Yulin , Guo Qiwei , Xie Xiaoting , Luo Ena , Li Jian , Li Qingge 
Published: November 2012

ABSTRACT

Long-term infection with high-risk human papillomavirus (HPV) is the leading cause of cervical cancer, while infection with low-risk HPV is the major reason for condylomata acuminata. An accurate, rapid, and convenient assay that is able to simultaneously detect, genotype, and quantify HPV would be of great clinical value yet remains to be achieved. We developed a three-color real-time PCR assay that is able to analyze 30 predominant HPV types in three reactions. The amplification curves indicated the presence of HPV, melting curve analysis identified the HPV genotype, and the quantification cycle value determined the quantity. We applied this assay to 647 cervical swab samples, and the results were compared with those obtained with a commercial genotyping system. The proposed assay had a limit of detection of 5 to 50 copies per reaction and a dynamic range of 5 × 10
1
to 5 × 10
6
copies per reaction. A comparison study showed that the overall sample concordance with the comparison method was 91.6% and the type agreement was greater than 98.7%. The quantification study demonstrated that the loads of HPV type 16 in 30 samples with cervical intraepithelial neoplasia grade III (CIN III) lesions were significantly higher than those in samples with CIN I lesions or CIN II lesions, and the results were concordant with those of the comparison method. The increased information content, high throughput, and low cost would facilitate the use of this real-time PCR-based assay in a variety of clinical settings.
Comparison of Three Different Methods for Detection of Shiga Toxin-Producing Escherichia coli in a Tertiary Pediatric Care Center
Authors: Vallières Emilie , Saint-Jean Maude , Rallu Fabien 
Published: November 2012

ABSTRACT

Shiga toxin-producing
Escherichia coli
(STEC) is a well-known cause of sporadic and epidemic food-borne gastroenteritis. A low infectious dose, approximately 10 microorganisms, is sufficient to cause disease that may lead to hemolytic-uremic syndrome. The objective of this study was to compare the performances of an in-house real-time PCR, a commercial enzyme immunoassay (EIA) (Premier EHEC; Meridian Bioscience), and culture on sorbitol MacConkey agar for the detection of STEC in a tertiary care pediatric hospital. Of 632 stool samples tested, 21 were positive for STEC. All were detected by PCR, 6 were detected by EIA, and only 5 O157 STEC isolates were identified by culture. Among the 15 specimens falsely negative by EIA, there were 9 Stx1, 2 Stx2, and 4 Stx1 and Stx2 STEC isolates. The latter group included 2 O157 STEC isolates that would have been missed if only EIA had been performed. To our knowledge, this is the first prospective study performed in a pediatric hospital which demonstrates the superiority of PCR over EIA for the detection of STEC. We conclude that PCR is specific and more sensitive than EIA. PCR should be considered for routine use in clinical settings where molecular detection facilities are available. Its lower limit of detection, equivalent to the infectious dose, is an obvious advantage for patient care and public health surveillance.
Gamma Interferon Release Assay for Monitoring of Treatment Response for Active Tuberculosis: an Explosion in the Spaghetti Factory
Authors: Denkinger Claudia M. , Pai Madhukar , Patel Meena , Menzies Dick 
Published: November 2012

ABSTRACT
Few studies have correlated the results of interferon (gamma interferon) release assays (IGRAs) with known markers of tuberculosis (TB) treatment response. We report the results of serial QuantiFERON-TB gold in-tube assay (QFT) testing on 149 patients with active tuberculosis and correlate the results with smear and culture conversion. We show that QFT results do not offer much value for treatment monitoring of TB disease.
Rapid Detection of Panton-Valentine Leukocidin in Staphylococcus aureus Cultures by Use of a Lateral Flow Assay Based on Monoclonal Antibodies
Authors: Monecke Stefan , Müller Elke , Buechler Joseph , Rejman John , Stieber Bettina , Akpaka Patrick Eberechi , Bandt Dirk , Burris Rob , Coombs Geoffrey , Hidalgo-Arroyo G. Aida , Hughes Peter , Kearns Angela , Abós Sonia Molinos , Pichon Bruno , Skakni Leila , Söderquist Bo , Ehricht Ralf 
Published: November 2012

ABSTRACT

Panton-Valentine leukocidin (PVL) is a virulence factor of
Staphylococcus aureus
, which is associated with skin and soft-tissue infections and necrotizing pneumonia. To develop a rapid phenotypic assay, recombinant PVL F component was used to generate monoclonal antibodies by phage display. These antibodies were spotted on protein microarrays and screened using different
lukF-PV
preparations and detection antibodies. This led to the identification of the optimal antibody combination that was then used to establish a lateral flow assay. This test was used to detect PVL in
S. aureus
cultures. The detection limit of the assay with purified native and recombinant antigens was determined to be around 1 ng/ml. Overnight cultures from various solid and liquid media proved suitable for PVL detection. Six hundred strains and clinical isolates from patients from America, Europe, Australia, Africa, and the Middle East were tested. Isolates were genotyped in parallel by DNA microarray hybridization for confirmation of PVL status and assignment to clonal complexes. The sensitivity, specificity, and positive and negative predictive values of the assay in this trial were 99.7, 98.3, 98.4, and 99.7%, respectively. A total of 302 clinical isolates and reference strains were PVL positive and were assigned to 21 different clonal complexes. In summary, the lateral flow test allows rapid and economical detection of PVL in a routine bacteriology laboratory. As the test utilizes cultures from standard media and does not require sophisticated equipment, it can be easily integrated into a laboratory's workflow and might contribute to timely therapy of PVL-associated infections.
Severe Hepatitis Associated with an Echovirus 18 Infection in an Immune-Compromised Adult
Authors: Lefterova Martina I. , Rivetta Claudia , George Tracy I. , Pinsky Benjamin A. 
Published: November 2012

ABSTRACT
Enteroviruses are recognized as important pathogens in pediatric patients; however, they are often overlooked as etiologic agents of disease in adults. Here, we report a case of echovirus 18-associated severe systemic infection and acute liver failure in an adult hematopoietic stem cell transplant recipient. Additionally, we illustrate the utility of molecular methods for the detection and typing of enteroviral infections.
Mycobacterial Interspersed Repetitive-Unit–Variable-Number Tandem-Repeat (MIRU-VNTR) Genotyping of Mycobacterium intracellulare for Strain Comparison with Establishment of a PCR-Based Database
Authors: Iakhiaeva Elena , McNulty Steven , Brown Elliott Barbara A. , Falkinham Joseph O. , Williams Myra D. , Vasireddy Ravikiran , Wilson Rebecca W. , Turenne Christine , Wallace Richard J. 
Published: November 2012

ABSTRACT

Strain comparison is important to population genetics and to evaluate relapses in patients with
Mycobacterium avium
complex (MAC) lung disease, but the “gold standard” of pulsed-field gel electrophoresis (PFGE) is time-consuming and complex. We used variable-number tandem repeats (VNTR) for fingerprinting of respiratory isolates of
M. intracellulare
from patients with underlying bronchiectasis, to establish a nonsequence-based database for population analysis. Different genotypes identified by PFGE underwent species identification using a 16S rRNA gene multiplex PCR. Genotypes of
M. intracellulare
were confirmed by internal transcribed spacer 1 (ITS1) sequencing and characterized using seven VNTR primers. The pattern of VNTR amplicon sizes and repeat number defined each specific VNTR type. Forty-two VNTR types were identified among 84 genotypes. PFGE revealed most isolates with the same VNTR type to be clonal or exhibit similar grouping of bands. Repetitive sequence-based PCR (rep-PCR) showed minimal pattern diversity between VNTR types compared to PFGE. Fingerprinting of relapse isolates from 31 treated patients using VNTR combined with 16S multiplex PCR unambiguously and reliably distinguished different genotypes from the same patient, with results comparable to those of PFGE. VNTR for strain comparison is easier and faster than PFGE, is as accurate as PFGE, and does not require sequencing. Starting with a collection of 167
M. intracellulare
isolates, VNTR distinguished
M. intracellulare
into 42 clonal groups. Comparison of isolates from different geographic areas, habitats, and clinical settings is now possible.