REF and sham

exposure sessions were counterbalanced and d

REF and sham

exposure sessions were counterbalanced and double blinded. Participants were exposed to either Global System for Mobile Communication (GSM) or unmodulated signals, and the mobile phone was positioned either on the left or on the right side of the head. Before and after REF and sham exposure participants completed a questionnaire to rate five symptoms. Any changes in the severity of the symptoms after REF exposure were check details compared with changes after sham exposure. Results: For one group of participants (N = 160), it was found that dizziness was affected by GSM exposure, but this was not consistently found with the other two groups of participants. No other significant effects were found. Conclusions: We did not find consistent evidence suggesting

that exposure to mobile phone REFs affect subjective symptoms. Even though we acknowledge ATM Kinase Inhibitor in vitro that more research is needed, we believe that our results give an important contribution to the research on mobile phone use and subjective symptoms.”
“Noise contributed by the probabilistic spiking times of neurons has an important and advantageous role in brain function. We go beyond the deterministic noiseless description of the dynamics of cortical networks and show how the properties of the system are influenced by the spiking noise. We review here recent results that show the direct link between brain activity and psychophysically quantified behaviors during a somatosensory detection task. We focus on the following

remarkable observation Buspirone HCl in this somatosensory task: when a near-threshold stimulus is presented, a sensory percept may or may not be produced. These perceptual judgments are believed to be determined by the fluctuation in activity of early sensory cortices. We show, however, that the behavioral outcomes associated with near-threshold stimuli depend on the neuronal fluctuations of more central areas to early somatosensory cortices. Furthermore, we show that the behavioral correlate of perceptual detection is given by a noise-driven transition in a multistable neurodynamical system. Thus, neuronal fluctuations can be an advantage for brain processing because they lead to probabilistic behavior in decision making in this and other sensory tasks.”
“Angiopoietin-1 (Ang-1) and angiopoietin-2 (Ang-2) have opposing effects on blood vessels, with Ang-2 being mainly induced during the endothelial barrier breakdown. It is known that spinal cord injury (SCI) induces lasting decreases in Ang-1 levels, underlying endothelial barrier disruption, but the expression of Ang-2 in spinal cord injury has not been studied. We characterized Ang-2 after SCI using a clinically relevant rat model of contusion SCI. We found that SCI induces marked and persistent upregulation of Ang-2 (up to 10 weeks after SCI), which does not reflect well-characterized temporal profile of the blood spinal cord barrier (BSCB) breakdown after SCI, and thus suggests other role(s) for Ang-2 in injured spinal cords.

Mothers, fathers, and adult children reported poorer relationship

Mothers, fathers, and adult children reported poorer relationship quality when they engaged in more conflict engagement behaviors. Adult children also reported poorer quality relationships when their mothers click here displayed more conflict engagement behaviors. Mothers reported poorer quality relationships when

their adult children engaged in more conflict disengagement.

Discussion. Findings suggest that even as adults, parents and children in poorer quality relationships may engage in potentially ineffective behaviors to resolve conflicts.”
“MS-based investigation of pancreatic fluid enables the high-throughput identification of proteins present in the pancreatic secretome. Pancreatic fluid is a complex admixture of digestive, inflammatory, and other proteins secreted by the pancreas into the duodenum, and thus is amenable to MS-based proteomic analysis. Recent advances in endoscopic techniques, in particular the endoscopic pancreatic function test (ePFT), have improved the selleck chemicals llc collection methodology of pancreatic fluid for proteomic analysis. Here, we provide an overview of MS-based proteomic techniques as applied to the study of pancreatic fluid. We address sample collection, protein extraction, MS sample preparation

and analysis, and bioinformatic approaches, and summarize current MS-based investigations of pancreatic fluid. We then examine the limitations and the future N-acetylglucosamine-1-phosphate transferase potential of such technologies in the investigation of pancreatic disease. We conclude that pancreatic fluid represents a rich reservoir of potential biomarkers and that the study of the molecular mechanisms of chronic pancreatitis may benefit substantially from MS-based proteomics.”
“Objectives. The aging literature suggests that life satisfaction and affective well being stabilizes or even increases during the aging process, and that death anxiety would decrease with aging. Experimental psychology literature shows that emotions play a critical role in information processing. The aim of the current study was to investigate whether death related versus nondeath-related threat words would lead

to differential attentional processing in middle aged versus older adults.

Method. Twenty-seven older adults between 74 and 90 year and 31 middle-aged adults between 40 and 50 years participated in the study. We used questionnaires to asses death anxiety and an exogenous cueing task to measure attention toward death related versus general threat words.

Results. Our results showed no age-related differences in self-reported death anxiety, but less attentional avoidance of threat in older adults. We failed to demonstrate differences between general and death-related threat.

Discussion. This is the first study investigating attentional processing of both death- and threat-related information in older versus younger adults.

The results also suggest that aconitine modulation of I-Kdr gatin

The results also suggest that aconitine modulation of I-Kdr gating is an important molecular mechanism through which it can contribute to neuronal firing. (C) 2008 Elsevier Ltd. All rights reserved.”

pain (NPP) due to sensory nerve injury is, in part, the result of peripheral sensitization leading to a long-lasting increase in synaptic plasticity in the spinal dorsal horn. Thus, activation of GABA-mediated inhibitory inputs from sensory neurons could be beneficial in the alleviation of NPP symptoms. Dorsal root ganglia (DRG) conduct painful stimulation from the periphery selleck chemicals to the spinal cord. Long-lasting down-regulation in GABA tone or sensitivity in DRG neurons has been reported in animals with neuropathy. To determine the function of GABA in DRG in the development of NPP, we examined how the acute pharmacological GABA(A)-receptor modulation of L5 DRG in vivo affects the development of NPP in rats with crush injury to the sciatic nerve. Direct application of muscimol and gaboxadol, GABA(A) agonists, to L5 DRG immediately after injury induced dose-dependent alleviation, whereas bicuculline and picrotoxin, GABA(A) antagonists, worsened NPP postaxonal injury. The pain-alleviating effects of muscimol and gaboxadol were blocked by bicuculline.

Muscimol, applied at the G418 cell line time of injury, caused complete and long-lasting abolishment of NPP development. However, when muscimol was applied after NPP had already developed, its pain-alleviating effect, although significant, was short-lived. Using a fluorescent tracer, sodium fluorescein, we confirmed that local DRG application results in minimal spread into the corresponding dorsal horn of the ipsilateral spinal cord. GABA(A) receptors in DRG are important in the development of NPP after peripheral nerve injury, making timely exogenous GABAergic manipulation at the DRG level a potentially useful therapeutic modality.

(C) 2008 IBRO. Published by Elsevier Ltd. All rights reserved.”
“Identifying candidate PDK4 genes related to complex diseases or traits and mapping their relationships require a system-level analysis at a cellular scale. The objective of the present study is to systematically analyze the complex effects of interrelated genes and provide a framework for revealing their relationships in association with a specific disease (asthma in this case). We observed that protein-protein interaction (PPI) networks associated with asthma have a power-law connectivity distribution as many other biological networks have. The hub nodes and skeleton substructure of the result network are consistent with the prior knowledge about asthma pathways, and also suggest unknown candidate target genes associated with asthma, including GNB2L1, BRCA1, CBL, and VAV1.

(C) 2008 Elsevier Ireland Ltd All rights reserved “
“In a f

(C) 2008 Elsevier Ireland Ltd. All rights reserved.”
“In a focused attention paradigm, saccadic reaction time (SRT) to a

visual target tends to be shorter when an auditory accessory stimulus is presented in close temporal and spatial proximity. Observed SRT reductions typically diminish as spatial disparity learn more between the stimuli increases. Here a visual target LED (500 ms duration) was presented above or below the fixation point and a simultaneously presented auditory accessory (2 ms duration) could appear at the same or the opposite vertical position. SRT enhancement was about 35 ms in the coincident and 10 ms in the disparate condition. In order to further probe the audiovisual integration mechanism, in addition to the auditory non-target an auditory see more masker (200 ms duration) was presented before, simultaneous to, or after the accessory stimulus. In all interstimulus interval

(ISI) conditions, SRT enhancement went down both in the coincident and disparate configuration, but this decrement was fairly stable across the ISI values. If multisensory integration solely relied on a feed-forward process, one would expect a monotonic decrease of the masker effect with increasing ISI in the backward masking condition. It is therefore conceivable that the relatively high-energetic masker causes Isoconazole a broad excitatory response of SC neurons. During this state, the spatial audio-visual information from multisensory

association areas is fed back and merged with the spatially unspecific excitation pattern induced by the masker. Assuming that a certain threshold of activation has to be achieved in order to generate a saccade in the correct direction, the blurred joint output of noise and spatial audio-visual information needs more time to reach this threshold prolonging SRT to an audio-visual object. (C) 2008 Elsevier Ireland Ltd. All rights reserved.”
“Background: In patients who have vascular disease or high-risk diabetes without heart failure, angiotensin-converting-enzyme (ACE) inhibitors reduce mortality and morbidity from cardiovascular causes, but the role of angiotensin-receptor blockers (ARBs) in such patients is unknown. We compared the ACE inhibitor ramipril, the ARB telmisartan, and the combination of the two drugs in patients with vascular disease or high-risk diabetes.

Methods: After a 3-week, single-blind run-in period, patients underwent double-blind randomization, with 8576 assigned to receive 10 mg of ramipril per day, 8542 assigned to receive 80 mg of telmisartan per day, and 8502 assigned to receive both drugs (combination therapy). The primary composite outcome was death from cardiovascular causes, myocardial infarction, stroke, or hospitalization for heart failure.

The sensitivity, specificity and repeatability of the assay were

The sensitivity, specificity and repeatability of the assay were validated by testing semen samples from 12 boars inoculated experimentally with PCV2, 10 boars infected naturally with PCV2, and 3 PCV2 negative control boars. The duplex qPCR assay was found to be more sensitive, specific, rapid, and repeatable than nested Avapritinib ic50 PCR (nPCR) methods for

the detection of PCV2 DNA in semen. Analysis of separated semen fractions by the duplex qPCR assay showed PCV2 DNA to be present mainly in the cell fraction as opposed to the seminal plasma fraction which is in contrast to previous reports. The duplex qPCR assay was found to be a valuable too] for accurate and quantitative detection of PCV2 DNA in boar semen. (c) 2008 Elsevier B.V. All rights reserved.”
“Basal forebrain neurons express the neurotrophin receptors, p75NTR and tyrosine S63845 ic50 kinase receptor A (TrkA). We tested the hypothesis that impairment of memory in rats could be achieved by RNA interference

(RNAi) -induced silencing of TrkA specifically within these neurons. A novel fusogenic, karyophilic immunoporter (fkAb(p75)-ipr) was constructed from the antibody, MC192 (monoclonal antibody to the rat neurotrophin receptor p75NTR, Ab(p75)), poly-L-lysine together with the hemagglutinin 2 and VP1 nuclear localization peptides of influenza and SV40 virus, respectively. Plasmid DNA constructs containing Dipeptidyl peptidase short hairpin sequences inhibitory to tyrosine kinase receptor A expression (TrkAi) and the gene encoding cGFP (green fluorescent protein from coral fish) was produced. These TrkAi plasmids were mixed with the immunoporter, forming the immunogene, TrkAi-fk-Ab(p75). A control TrkAsc complexed with fkAb(p75) (TrkAsc-fkwAb(p75)) immunogene was constructed from a scrambled sequence (TrkAsc) and fkAb(p75-ipr). Rats were infused using an osmotic mini-pump into the third ventricle with either TrkAi-fkAb(p75) or TrkAsc-fkAb(p75). Naive rats were also

included as additional controls. After 7 days, examination of gene expression on forebrain sections of some rats revealed cGFP expression in TrkA neurons. Fifteen to 19 days after infusion, rats were tested in a Morris water maze apparatus. Animals that received TrkAi-fkAb(p75) showed significantly impaired spatial memory learning ability compared with naive or TrkAsc-fkAb(p75)-treated rats. Western blot and immunofluorescence analysis showed that TrkA protein levels and numbers of TrkA positive neurons were reduced by 60% and 55% respectively in TrkAi-fkAb(p75)-infused rats compared with infused controls or naive animals. We conclude that p75-receptor-mediated RNAi-induced silencing of genes offers a novel and powerful way to study the function of specific endogenous genes within distinct neuronal subpopulations of the brain.


The physiological adaptation of cells occ


The physiological adaptation of cells occurred with cell membrane of Lact. helveticus during vacuum drying of cells in the presence of sorbitol.

Significance and Impact of the Study:

The study showed selleck kinase inhibitor that physiological adaptation with membrane of the cells occurred during the drying process. The insight implies that instead of viability improvement of dried cells by the conventional

stress induction during cultivation, the induction may be exercised thereafter without compromising growth of the cells.”
“We investigated the specificity of cyan fluorescent protein (CFP) expression in retinal ganglion cells (RGCs) of the transgenic Thy1-CFP (B6.Cg-Tg(Thy1-CFP)23Jrs/J) mouse line, and the characteristics of these cells after optic nerve injury. RGCs of adult Thy1-CFP mice were retrogradely labeled with fluorochrome (2% fluorogold [FG]) from

the superior colliculi (SC). Animals were sacrificed 7 days after RGC labeling. Retinas were fixed and whole-mounted. CFP and FG-positive cells were visualized and imaged separately. Cells positive for CFP, FG, or co-labeled were counted. In another group of animals, the left optic nerves were transected 7 days after FG labeling. They were sacrificed 7 or 21 days after transection. The retinas were whole-mounted LY411575 and the characteristics of CFP-expressing cells examined. CFP-expressing cells were distributed evenly throughout the retinas of Thy1-CFP mice. The average densities of CFP and FG-positive cells in the retina were 2778 +/- 216 and 3230 +/- 157 cells/mm(2), respectively. 93.2 +/- 1.6% of CFP-expressing cells were also labeled with FG. However, only 79.9 +/- 2.5% of FG-labeled RGCs expressed CFP. The number of CFP-expressing cells decreased dramatically after transection. Cells with spindle shape, immunohistochemically identified as microglia, were seen

in the retina with CFP expression at both 7 and 21 days after optic nerve transection. In retinas of Thy1-CFP mice, CFP is expressed by the large majority of RGCs, but not exclusively by RGCs. CFP is internalized by phagocytosing cells Sitaxentan after injury to RGCs. (C) 2009 Elsevier Ireland Ltd. All rights reserved.”

To evaluate the use of Enterobacterial Repetitive Intergenic Consensus PCR (ERIC-PCR)-derived probes and primers to specifically detect bacterial strains in an activated sludge microbial community.

Methods and Results:

ERIC-PCR was performed on two phenol-degrading bacterial strains, Arthrobacter nicotianae P1-7 and Klebsiella sp. P8-14. Their amplicons were DIG labelled for use as probes and then hybridized with ERIC-PCR fingerprints. The results showed the distinct band patterns for both bacterial strains. Strain-specific PCR primers were designed based on the sequences of ERIC-PCR bands.

Methods: Blood pressure and heart rate (HR) were measured at rest

Methods: Blood pressure and heart rate (HR) were measured at rest and in response to a brief time-pressured mental arithmetic stress in 1647 adults. At the same session and 5 years later, height, weight, waist and hip circumference were measured and body mass index (BMI) and waist-hip ratio were computed. Obesity was defined as a body mass index

of >= 30 kg/m(2). Results: Contrary to expectations, the most robust and consistent results to emerge from cross-sectional analyses were negative associations between all three measures of adiposity and HR reactivity; those with greater BMI and waist-hip ratios and those categorized as obese displayed smaller HR reactions to stress. In prospective analyses, high HR reactivity was associated KPT-330 with a reduced likelihood of becoming obese in the subsequent 5 years. Conclusions: Our analyses suggest that it is low, not high, HR reactivity that is related to adiposity.

Low HR reactivity, probably by reflecting generally blunted sympathetic nervous system LXH254 cell line reactions to challenge, may be a risk marker for developing obesity.”
“To facilitate genotype-specific high-throughput studies of hepatitis C virus (HCV), we have developed reporter viruses using JFH1-based recombinants expressing core-nonstructural protein 2 (NS2) of genotype 1 to 7 prototype isolates. We introduced enhanced green fluorescent protein (EGFP) into NS5A domain III of the genotype 2a virus J6/JFH1 [2a(J6)]. During Huh7.5 cell culture adaptation, 2a(J6)-EGFP acquired a 40-amino-acid (aa) (Delta 40) or 25-aa (Delta 25) deletion in NS5A domain II, rescuing the impairment of viral assembly caused Lonafarnib molecular weight by the EGFP insertion. Delta 40 conferred efficient growth characteristics to 2a(J6) tagged with EGFP, DsRed-Express2, mCherry,

or Renilla luciferase (RLuc), yielding peak supernatant infectivity titers of 4 to 5 log(10) focus-forming units (FFU)/ml. 2a(J6) with Delta 40 or Delta 25 was fully viable in Huh7.5 cells. In human liver chimeric mice, 2a(J6)-EGFP Delta 40 acquired various deletions in EGFP, while 2a(J6)Delta 40 did not show an impaired viability. We further developed panels of JFH1-based genotype 1 to 7 core-NS2 recombinants expressing EGFP- or RLuc-NS5A Delta 40 fusion proteins. In cell culture, the different EGFP recombinants showed growth characteristics comparable to those of the nontagged recombinants, with peak infectivity titers of 4 to 5 log(10) FFU/ml. RLuc recombinants showed slightly less efficient growth characteristics, with peak infectivity titers up to 10-fold lower. Overall, the EGFP and RLuc recombinants were genetically stable after one viral passage. The usefulness of these reporter viruses for high-throughput fluorescence- and luminescence-based studies of HCV-receptor interactions and serum-neutralizing antibodies was demonstrated.

These results do not support findings of prefrontal cortical modu

These results do not support findings of prefrontal cortical modulation of activity with COMT genotype, but MK-2206 in vivo instead suggest that COMT val/val genotype can modulate the activity of the posterior cingulate and may indicate the potential network effects of COMT genotype on the default mode network. Neuropsychopharmacology (2011) 36, 763-771; doi:10.1038/npp.2010.210;

published online 8 December 2010″
“Rotaviruses, the single most important agents of acute severe gastroenteritis in children, are nonenveloped viruses formed by a three-layered capsid that encloses a genome formed by 11 segments of double-stranded RNA. The mechanism of entry of these viruses into the host cell is not well understood. The best-studied strain, RRV, which is sensitive to neuraminidase (NA) treatment of the cells, uses integrins alpha 2 beta 1 and alpha A-1210477 v beta 3 and the heat shock protein hsc70 as receptors and enters MA104 cells through a non-clathrin-, non-caveolin-mediated pathway that depends on a functional dynamin and on the presence of cholesterol on the cell surface. In this work, using a combination of pharmacological, biochemical, and genetic approaches, we compared the entry characteristics of four rotavirus

strains known to have different receptor requirements. We chose four rotavirus strains that represent all phenotypic combinations of NA resistance or sensitivity and integrin dependence or independence. We found that even though all the strains share their requirements for hsc70, dynamin, and cholesterol, three of them differ from the simian strain RRV in the endocytic pathway used. The human strain Wa, porcine strain TFR-41, and bovine strain UK seem to enter the cell

through clathrin-mediated endocytosis, since Sunitinib in vivo treatments that inhibit this pathway block their infectivity; consistent with this entry route, these strains were sensitive to changes in the endosomal pH. The inhibition of other endocytic mechanisms, such as macropinocytosis or caveola-mediated uptake, had no effect on the internalization of the rotavirus strains tested here.”
“The lateral septum (LS) has been shown to have a key role in emotional processes and stress responses. However, the exact role of the LS on stress modulation is not clear, as previous lesion studies mostly used electrolytic lesions, thereby destroying the whole septal area, including medial components and/or fibers of passage. The aim of the present study was therefore, to investigate the effects of selective excitotoxic ablation of the LS on neuroendocrine and behavioral stress responses in rats. Bilateral ibotenic acid lesions of the LS increased hypothalamo-pituitary-adrenocortical (HPA) axis responses to forced swim stress indicated by enhanced plasma ACTH and corticosterone responses and higher stress-induced c-Fos-like immunoreactivity in the paraventricular hypothalamic nucleus.

In experiment 2, the early C1-component, which had an average max

In experiment 2, the early C1-component, which had an average maximum at 67 ms following target onset, was significantly more negative when subjects pointed at

the stimuli. Traditionally, the C1 has been regarded as a sensory component, but recent studies have linked it to higher order processing, such as attention and expectations. Thus, the present data indicate that target processing for eye or hand movements is already context-specific during early visual information processing. We suggest that differences in a target’s relevance for upcoming movements modify target processing as well as sensory expectations. (C) 2013 Published by CB-839 mouse Elsevier Ireland Ltd and the japan Neuroscience Society.”
“The loss of expression of the fragile X mental retardation protein (FMRP) leads to fragile X syndrome. FMRP has two types of RNA binding domains, two K-homology domains and an arginine-glycine-glycine box domain, and it is proposed to act as a translation regulator of specific messenger RNA. The interest to produce sufficient quantities of pure recombinant FMRP for biochemical and biophysical studies is high. However, the recombinant

bacterial expression of FMRP has had limited success, and subsequent recombinant eukaryotic and Selleck KPT 330 in vitro expression has also resulted in limited success. In addition, the in vitro and eukaryotic expression systems may produce FMRP which is posttranslationally modified, as phosphorylation and arginine

methylation have been shown to occur on FMRP. In this study, we have successfully isolated the conditions for recombinant expression, purification and long-term storage of FMRP using Escherichia coli, with a high yield. The expression of FMRP using E. cob renders the protein devoid of the posttranslational modifications of phosphorylation and arginine methylation, allowing the study of the direct effects of these modifications individually and simultaneously. In order to assure that FMRP retained activity throughout the process, we used fluorescence spectroscopy to assay the binding activity of the FMRP arginine-glycine-glycine box for the semaphorin 3F mRNA and confirmed that FMRP remained active. (C) 2010 Elsevier Inc. All rights reserved.”
“Human enteroviruses N-acetylglucosamine-1-phosphate transferase (EVs) are the leading cause of CNS-associated disease in childhood. Identification of the EV types that patients are infected with is essential for monitoring outbreaks, the emergence of new types or variants, epidemiological surveillance and contributes to patient management. Rapid and sensitive molecular detection methods are frequently used to detect EVs/HPeVs directly from CSF. This requires that sensitive EV typing methods from CSF material need to be developed.

In the present study two nested PCR-based typing assays were evaluated.

In addition, the PCR-ELOSA system showed high accuracy (CV <=

In addition, the PCR-ELOSA system showed high accuracy (CV <= 6.36%) and even higher reproducibility (CV <= 5.55%). Thus, this novel PCR-ELOSA system provides a sensitive and versatile alternative

to Current HCV detection assays. (c) 2008 Elsevier B.V. All rights reserved.”
“Relapse to alcohol use after periods of abstinence is a hallmark behavioral pathology of alcoholism and a major find more clinical problem. Emerging evidence indicates that metabotropic glutamate receptor 5 (mGluR5) antagonists attenuate relapse to alcohol-seeking behavior but the molecular mechanisms of this potential therapeutic effect remain unexplored. The extracellular signal-regulated kinase (ERK1/2) pathway is downstream of mGluR5 and has been implicated in addiction. We sought to determine if cue-induced reinstatement of alcohol-seeking behavior, and its reduction by an mGluR5 antagonist, is associated with changes in ERK1/2 activation

in reward-related limbic brain regions. Selectively-bred alcohol-preferring (P) rats were trained to lever press on a concurrent schedule of alcohol (15% v/v) vs. water reinforcement. Following 9 days of extinction, rats were given an additional extinction trial or injected with the mGluR5 antagonist MPEP (0, 1, 3, or 10 mg/kg) and tested for cue-induced reinstatement. Brains were removed 90-min later from the rats in the extinction and MPEP (0 or 10 mg/kg) conditions for analysis of p-ERK1/2, total ERK1/2, and p-ERK5 PD0332991 immunoreactivity (IR). Cue-induced reinstatement of alcohol-seeking behavior was associated with a three to five-fold increase in p-ERK1/2 IR in the basolateral amygdala and nucleus accumbens shell. MPEP administration blocked both the relapse-like behavior and increase in p-ERK1/2 IR. p-ERK1/2 IR in the central amygdala and NAcb core was dissociated with the relapse-like behavior and the pharmacological effect of rnGluR5 blockade. No changes in total

ERK or p-ERK5 were observed. These results suggest that exposure to cues previously associated with alcohol self-administration is sufficient to produce concomitant increases in relapse-like behavior and ERK1/2 Quisqualic acid activation in specific limbic brain regions. Pharmacological compounds, such as mGluR5 antagonists, that reduce cue-induced ERK1/2 activation may be useful for treatment of relapse in alcoholics that is triggered by exposure to environmental events. (C) 2008 Elsevier Ltd. All rights reserved.”
“An approach for determination of hepatitis C virus (HCV) quasispecies by end-point limiting-dilution real-time PCR (EPLD-PCR) is described. It involves isolation of individual coexisting sequence variants of the hypervariable region 1 (HVR1) of the HCV genome from serum specimens using a limiting-dilution protocol.