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Presents a survey of the relationship between magnetism and superconductivity in high-temperature superconductors. Discussion of the electronic structure; Mobile charges in an antiferromagnet; Discussion of superconductivity.

The risks associated with in vivo and ex vivo use of Campath-1H and -1G in a cohort of 206 stem cell transplant recipients for human CMV (HCMV) DNAemia have been quantified. DNAemia showed a biphasic incidence pattern with an inflexion at day 60. The first phase had a linear risk rate for HCMV DNAemia of 0.3% per day, whereas the second phase had a substantially lower risk rate of 0.058% per day. In multivariable analyses, risk factors for early DNAemia were HCMV serostatus, radiotherapy-based conditioning and CD34 stem cell dose, with the use of in vivo Campath-1H having the most significant risk (hazards ratio=3.68; 95% CI=2.02–6.72; P<0.001). Ex vivo use of Campath was not associated with an increased risk for HCMV DNAemia. Patients receiving either in vivo Campath-1H or -1G experienced HCMV DNAemia earlier (27 and 33 days, respectively) compared with patients receiving no Campath (time to DNAemia, 51 days; P=0.0006). Multivariable analysis of risk factors for HCMV DNAemia occurring beyond 100 days after transplant were older age, acute GVHD>grade II and a lower CD34 stem cell dose, whereas Campath-1H use was not associated with late HCMV DNAemia. [ABSTRACT FROM AUTHOR]

Aim: To investigate the relation between cytomegalovirus (CMV) viral load on dried blood spots (DBS) from newborn biochemical screening ("Guthrie") cards, and sensorineural hearing loss (SNHL) in congenital CMV. Design: Cross-sectional study with retrospective case-note review. Setting: Seven paediatric audiology departments in the United Kingdom. Patients: 84 children, median age 7 years: 43 with known congenital CMV, 41 with unexplained SNHL. Interventions: Half a DBS was tested for CMV DNA viral load by quantitative real-time polymerase chain reaction (PC A). Main outcome measures: Pure tone average hearing thresholds (0.5-4 kHz). Results: DBS CMV DNA viral load significantly correlated with hearing thresholds for the worse and better hearing ears (Spearman's rank correlations: r = 0.445, p = 0.008 and r = 0.481, p = 0.004 respectively). Multivariable logistic regression showed that the effect of DBS viral load on the risk of SNHL remained important, when age and central nervous system involvement had been taken into account (odds ratio (OR) 2.76, 95% confidence interval (Cl) 1.14 to 6.63, p = 0.024). The mean log DBS viral load was significantly higher in children with SNHL than in those with normal hearing (2.69 versus 1.64, 95% Cl -1.84 to -0.27, p = 0.01). 8/35 (23%) children with unexplained SNHL tested positive for CMV DNA on DBS. One false positive result was obtained. Conclusion: The risk of SNHL increased with DBS viral load. Further studies should investigate whether DBS CMV testing has a role in identifying asymptomatic congenitally infected neonates at risk of SNHL, and whether antiviral treatment can reduce this risk. [ABSTRACT FROM AUTHOR]

Background. Human immunodeficiency virus (HIV) may influence the outcome and natural history of hepatitis C virus (HCV) infection through an impact on acute HCV-specific T cell responses. Methods. Fifty-five HIV-positive males with acute HCV infection were identified; monoinfected individuals (n = 8) were used for peripheral blood mononuclear cell comparison. In 14 coinfected and 8 HCV-monoinfected patients, HCV-specific T cell responses against a range of HCV antigens were assessed using interferon (IFN)-γenzyme-linked immunospot (ELISpot) and proliferation assays. E1/E2 region genetic diversity and the selection pressure on the virus were measured in 8 coinfected patients by use of cloned sequences over time. Results. HCV persisted in 52 (95%) coinfected individuals. HCV/HIV coinfection significantly reduced IFN-γELISpot responses versus those in HCV-monoinfected individuals, especially against nonstructural proteins (1/10 vs. 5/8; P = .008). In coinfected patients, increasedHCVgenetic diversity was observed between the first and subsequent time points, with no evidence for positive selection in the E1/E2 region sequenced. Conclusion. HIV coinfection is associated with increased rates of HCV persistence and a lack of critical CD4T cell responses, with no evidence of immune selection pressure during early HCV infection. Loss of key cellular immune responses against HCV during acute disease may contribute to the failure of early host control of HCV in HCV/HIVcoinfected patients. [ABSTRACT FROM AUTHOR]

We show that at least half of patients with common variable immunodeficiency (CVID) have circulating CD8+ T cells specific for epitopes derived from cytomegalovirus (CMV) and/or the Epstein–Barr virus (EBV). Compared to healthy age-matched subjects, more CD8+ T cells in CVID patients were committed to CMV. Despite previous reports of defects in antigen presentation and cellular immunity in CVID, specific CD4+ and CD8+ T cells produced interferon (IFN)-γ after stimulation with CMV peptides, and peripheral blood mononuclear cells secreted perforin in response to these antigens. In CVID patients we found an association between a high percentage of circulating CD8+ CD57+ T cells containing perforin, CMV infection and a low CD4/CD8 ratio, suggesting that CMV may have a major role in the T cell abnormalities described previously in this disease. We also show preliminary evidence that CMV contributes to the previously unexplained severe enteropathy that occurs in about 5% of patients. [ABSTRACT FROM AUTHOR]

The availability of valganciclovir (VGCV) has significantly simplified the treatment of human cytomegalovirus (HCMV) infection after solid-organ transplantation. We show that there was no difference in the kinetics of the decrease in HCMV load after preemptive therapy with VGCV in 22 solid-organ transplant recipients (T1/2=2.16 days), compared with that in 23 patients treated with intravenous ganciclovir (GCV) (T(1/2) = 1.73 days; P=.63). Preemptive therapy with VGCV provides control of HCMV replication that is comparable to that achieved with preemptive intravenous therapy with GCV. [ABSTRACT FROM AUTHOR]

This experiment examines the effect that computer experience and various combinations of feedback (auditory, haptic, and/or visual) have on the performance of older adults completing a drag-and-drop task on a computer. Participants were divided into three computer experience groups, based on their frequency of use and breadth of computer knowledge. Each participant completed a series of drag-and-drop tasks under each of seven feedback conditions (three unimodal, three bimodal, one trimodal). Performance was assessed using measures of efficiency and accuracy. Experienced users responded well to all multimodal feedback while users without experience responded well to auditory-haptic bimodal, but poorly to haptic-visual bimodal feedback. Based on performance benefits for older adults seen in this experiment, future research should extend investigations to effectively integrate multimodal feedback into GUI interfaces in order to improve usability for this growing and diverse user group. [ABSTRACT FROM AUTHOR]

The aim of this study was to correlate human herpesvirus (HHV)-6 viral load with clinical symptoms in allogeneic stem cell transplant (SCT) patients. Seventy-four patients were monitored during the first 3 months after SCT using a qualitative polymerase chain reaction (PCR) for HHV-6 DNA. HHV-6 was detected in 181 out of 494 samples (36%) from 58 (78%) patients. These 181 samples were analysed using a quantitative competitive PCR. DNA could be quantified from 146 out of 181 samples (80·6%). The HHV-6 viral load was highest at 4 weeks compared with 8 weeks (P < 0·001) and 12 weeks (P = 0·01) after SCT. Three patients had HHV-6 encephalitis and one patient had hepatitis. The HHV-6 DNA levels were higher in patients with HHV-6 than in those without HHV-6 (P = 0·01). Patients who received grafts from unrelated or HLA-mismatched family donors had significantly higher HHV-6 DNA levels than patients who received grafts from matched sibling donors (P < 0·001). In a multiple regression model, unrelated donor grafts (P < 0·001) and use of intravenous immunoglobulin prophylaxis (P = 0·04) influenced HHV-6 DNA levels. HHV-6 viral load was significantly correlated with delayed platelet engraftment in both univariate (P < 0·01) and multivariate analysis, and to the number of platelet transfusions. [ABSTRACT FROM AUTHOR]

The three betaherpesviruses known to infect humans are cytomegalovirus (CMV) and human herpesviruses 6 and 7 (HHV-6 and -7). All three viruses can infect opportunistically after organ transplantation. CMV causes a variety of end-organ diseases, including pneumonitis, hepatitis and gastrointestinal ulceration. Patients who develop overt CMV disease have significantly higher CMV viral loads than infected patients without evidence of clinical disease. A high CMV viral load largely explains the previously described risk factors for the development of CMV disease, which include donor/recipient serostatus before transplant and viraemia after transplant. CMV also causes some cases of allograft rejection, which can be prevented by antiviral prophylaxis. Application of similar quantitative methods for the study of HHV-6 and -7 have shown that HHV-6 and CMV are significantly and independently associated with biopsy-proven graft rejection after liver transplantation. The full clinicopathological significance of the betaherpesviruses may, thus, be greater than is currently appreciated. [ABSTRACT FROM AUTHOR]

The three betaherpesviruses known to infect humans are cytomegalovirus (CMV) and human herpesviruses 6 and 7 (HHV-6 and -7). All three viruses can infect opportunistically after organ transplantation. CMV causes a variety of end-organ diseases, including pneumonitis, hepatitis and gastrointestinal ulceration. Patients who develop overt CMV disease have significantly higher CMV viral loads than infected patients without evidence of clinical disease. A high CMV viral load largely explains the previously described risk factors for the development of CMV disease, which include donor/recipient serostatus before transplant and viraemia after transplant. CMV also causes some cases of allograft rejection, which can be prevented by antiviral prophylaxis. Application of similar quantitative methods for the study of HHV-6 and -7 have shown that HHV-6 and CMV are significantly and independently associated with biopsy-proven graft rejection after liver transplantation. The full clinicopathological significance of the betaherpesviruses may, thus, be greater than is currently appreciated. [ABSTRACT FROM PUBLISHER]

The Fermi liquid theory of the normal state and the BCS-Eliashberg theory of the superconducting state were designed for good metals not for doped antiferromagnetic insulators, such as the high temperature superconductors. Consequently, it is necessary to understand the electronic structure of the doped insulator and to develop a new mechanism and many-body theory of superconductivity for these materials. It will be argued that, since the motion of a single hole in an antiferromagnet is frustrated, the driving force for the physics of a finite concentration of doped holes is the need to reduce their zero-point kinetic energy. This proceeds in three steps that are reflected in a sequence of crossovers and phase transitions. First of all, the system forms a charge-inhomogeneous state – an electronic liquid crystal phase, involving an array of metallic stripes, which lowers the kinetic energy along a stripe. In the direction perpendicular to the stripes, the kinetic energy is lowered by pair hopping, which proceeds in two steps. Local pair hopping induces spin pairing and then, at a lower temperature, pair hopping from stripe to stripe produces superconducting phase coherence. Some of the experimental support for the various aspects of this model will be described. [ABSTRACT FROM AUTHOR]

Qualitative and competitive-quantitative nested polymerase chain reaction (PCR) assays were developed for human herpesvirus 7 (HHV-7). These assays amplify a DNA sequence encoding part of the HHV-7 homologue of the human herpesvirus 6 (HHV-6) U42 gene. The PCR assays were used to analyze peripheral blood DNA (pbDNA) and saliva from 24 healthy volunteers. The prevalence of HHV-7 in saliva was 96%, with a median virus load of 1.1 x 10(6) copies/mL. Longitudinal analysis revealed sustained virus load, suggesting continued active viral replication. Analysis of 1 microgram of pbDNA showed the prevalence of HHV-7 to be 83%, with a median virus load of 40 copies (267 copies/10(6) cells). Analysis of sequential pbDNA samples showed individuals to have stable levels of HHV-7 virus load. These data demonstrate persistence of HHV-7 at two distinct sites and provide baseline data allowing comparisons with HHV-7 load in immunocompromised patients. [ABSTRACT FROM AUTHOR]

Quantitative competitive PCR was used to monitor the quantity of cytomegalovirus (HCMV) in 1647 blood samples from 110 BMT recipients. DNAemia was detected in 49/110 (45%) of the patients, of whom 15/49 experienced HCMV disease. Peak virus load during surveillance was elevated in symptomatic (median 4.5 log10 genomes/ml) vs asymptomatic patients (median 3.6 log10 genomes/ml, P = 0.002) and was also significantly elevated in HCMV seropositive recipients of seronegative marrow, (R+D-, median 5.0 log10), compared to those in the R-D- and R+D+ groups (P < 0.01 and <0.005). odds ratios for disease per 0.25 log10 increase in viral load, recipient seropositivity and aGVHD were 1.43 (P = 0.004), 6.60 (P = 0.05) and 3.17 (P = 0.08), respectively. In multivariate logistic regression analysis only elevated viral load remained a significant risk factor for HCMV disease. The computed disease probability viral load curve showed a rapid increase in disease risk at viral loads between 3.8 and 5.5 log10 genomes/ml in blood, and odds ratios for disease were determined for different threshold viral loads. These data demonstrate the central role of viral load in the pathogenesis of HCMV in BMT recipients and provide an additional marker for targeting and monitoring therapy. [ABSTRACT FROM AUTHOR]

Presents research which studied the interactions between stripes in an antiferromagnetic insulator. Ground state of such an insulator; What stripes are; Elimination of a transition to an insulating ordered charge-density-wave (CDW) state at low temperatures; Existence of electronic quantum liquid-crystal phases in a copper oxide superconductor.

Primary human herpesvirus 6 (HHV-6) and 7 (HHV-7) infections were identified in febrile children by qualitative and quantitative polymerase chain reaction (PCR) assays. Diagnosis was based on the differential detection of viral DNA in peripheral blood mononuclear cells (PBMC), but not in saliva. Six of 41 febrile infants, but none of seven non-febrile controls, were identified with primary infections (three HHV-6, three HHV-7). These children had significantly higher viral loads in PBMC (HHV-6, median 24213 genomes/10(6) PBMC; HHV-7, median 6,040,000 genomes/10(6) PBMC) than DNA-aemic, saliva PCR positive children (HHV-6, median 1606 genomes/10(6) PBMC, p < 0.01; HHV-7, median 7089 genomes/ 10(6) PBMC, p < 0.05). Viral DNA was detected in serum by PCR in only 50% of primary infections. All three children with primary HHV-7 infection had febrile convulsions. Thus PCR, including quantitative assays, may identify primary HHV-6 and HHV-7 infections when an appropriate combination of clinical specimens is used. [ABSTRACT FROM AUTHOR]

Samples of blood and urine were collected at baseline, week 4, and week 8 and then every 8 weeks from 310 patients entering a controlled trial of prophylaxis with valaciclovir versus acyclovir. Samples were tested under code by polymerase chain reaction (PCR) in one laboratory. The median number of samples collected from each patient was 5 for blood (range, 0–15) and 5 for urine (range, 0–15). Both baseline PCR viremia and PCR viruria were significantly associated with future cytomegalovirus (CMV) disease (P = .002 and P = .02, respectively). The greatest effect of valaciclovir on CMV disease was seen in patients who were PCR-positive in blood at baseline (P = .002), although a significant effect was also seen in those who were PCR-negative in urine (P = .02). Thus, PCR viremia provides prognostic information about CMV disease in AIDS patients, and valaciclovir showed activity as both a preemptive and prophylactic agent. [ABSTRACT FROM PUBLISHER]

Longitudinal analysis of 162 liver transplant recipients identified 51 patients who were viremic. Virus load was determined in 47 of these patients using quantitative-competitive polymerase chain reaction. Peak virus load was significantly higher in 20 symptomatic patients than 27 asymptomatic patients (P < .0001). Elevated virus load, donor seropositivity, and total methylprednisolone dosage were risk factors for human cytomegalovirus (HCMV) disease (odds ratio [OR], 2.22/0.25 log10 increase in virus load, P < .001; OR, 4.11, P < .05; OR, 1.30/1-g increment in methylprednisolone, P < .01). Methylprednisolone and virus load were independent risk factors in a multivariate analysis (OR, 2.70/1-g increase, P < .003; OR, 1.61/0.25 log10 increase, P < .03, respectively). Virus loads of 104.75–105.25 genomes/mL of blood were associated with an increased disease probability; the latter was shifted to lower virus loads with increasing quantities of methylprednisolone. These data illustrate the central role of virus load in HCMV pathogenesis. [ABSTRACT FROM PUBLISHER]

The conceptualization of predisposition to Post-Traumatic Stress Disorders (PTSD) is summarized by three models: (1) predisposition due to preexisting psychopathology, (2) predisposition due to preexisting traits or characteristics considered normal, and (3) predisposition due to preexisting experience of specified stressors in family of origin. The investigation reported can be subsumed under the third model. The study involved the exploration of major stressors found in families of origin of 40 veterans, 20 who later developed PTSD and 20 who did not develop PTSD, with key demographic and military service variables balanced across groups. Additionally, the study focused on childhood perceptions of major stressors in family of origin. Findings suggest PTSD veterans had greater childhood stress related to parental alcoholism and unemployment than did non-PTSD counterparts. Further, the data suggest two major sets of childhood perceptions separate the two groups of veterans: (1) parental alcoholism/unemployment in the perception of PTSD participants, and (2) parental strictness/delegation of responsibility in the perception of non-PTSD participants. Methodological refinements are discussed that are needed to better hone in on the connection between family system stressors during primary socialization, subsequent phenomenology, and risk for PTSD. [ABSTRACT FROM AUTHOR]

That the superconducting transition in underdoped high temperature superconductors is controlled by phase ordering, implies that pairing is a local phenomenon that occurs on an intermediate length scale, and typically at a temperature above T c . The discovery of local stripe order in the LSCO family of high temperature superconductors, along with the theoretical suggestion that such structures are a general feature of doped antiferromagnets lead us further to propose that in fact pairing occurs in the vicinity of an individual stripe. The transition to a superconducting state then follows at lower temperature due to Josephson coupling between stripes. In this paper we review our microscopic model of high temperature pairing on individual stripes. [ABSTRACT FROM AUTHOR]