An important step in the herpesvirus life cycle is the switch from latency to lytic reactivation. In order to study the life cycle of Kaposi's sarcoma-associated herpesvirus (KSHV), we developed a gene expression system in KSHV-infected primary effusion lymphoma cells. This system uses Flp-mediated efficient recombination and tetracycline-inducible expression. The Rta transcriptional activator, which acts as a molecular switch for lytic reactivation of KSHV, was efficiently integrated downstream of the Flp recombination target site, and its expression was tightly controlled by tetracycline. Like stimulation with tetradecanoyl phorbol acetate (TPA), the ectopic expression of Rta efficiently induced a complete cycle of viral replication, including a well-ordered program of KSHV gene expression and production of infectious viral progeny. A striking feature of Rtamediated lytic gene expression was that Rta induced KSHV gene expression in a more powerful and efficient manner than TPA stimulation, indicating that Rta plays a central, leading role in KSHV lytic gene expression. Thus, our streamlined gene expression system provides a novel means not only to study the effects of viral gene products on overall KSHV gene expression and replication, but also to understand the natural viral reactivation process.

The functional human immune system, including T, B, and natural killer lymphocytes, is reconstituted in NOD/Shi-scid/IL-2Rgamma(null) (NOG) mice that receive hematopoietic stem cell transplants. Here, we show that these humanized mice can recapitulate key aspects of Epstein-Barr virus (EBV) infection in humans. Inoculation with approximately 1 x 10(3) TD(50) (50% transforming dose) of EBV caused B cell lymphoproliferative disorder, with histopathological findings and latent EBV gene expression remarkably similar to that in immunocompromised patients. Inoculation with a low dose of virus (

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IMPORTANCE No highly effective interventions to prevent delirium have been identified. OBJECTIVE To examine whether ramelteon, a melatonin agonist, is effective for the prevention of delirium. DESIGN, SETTING, AND PARTICIPANTS A multicenter, rater-blinded, randomized placebo-controlled trial was performed in intensive care units and regular acute wards of 4 university hospitals and 1 general hospital. Eligible patients were 65 to 89 years old, newly admitted due to serious medical problems, and able to take medicine orally. Patients were excluded from the study if they had an expected stay or life expectancy of less than 48 hours. INTERVENTIONS Sixty-seven patients were randomly assigned using the sealed envelope method to receive ramelteon (8 mg/d; 33 patients) or placebo (34 patients) every night for 7 days. MAIN OUTCOMES AND MEASURES Incidence of delirium, as defined by the Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition). RESULTS Ramelteon was associated with a lower risk of delirium (3% vs 32%; P = .003), with a relative risk of 0.09 (95% CI, 0.01-0.69). Even after risk factors were controlled for, ramelteon was still associated with a lower incidence of delirium (P = .01; odds ratio, 0.07 [95% CI, 0.008-0.54]). The Kaplan-Meier estimates of time to development of delirium were 6.94 (95% CI, 6.82-7.06) days for ramelteon and 5.74 (5.05-6.42) days for placebo. Comparison by log-rank test showed that the frequency of delirium was significantly lower in patients taking ramelteon than in those taking placebo (χ 2 = 9.83; P = .002). CONCLUSIONS AND RELEVANCE Ramelteon administered nightly to elderly patients admitted for acute care may provide protection against delirium. This finding supports a possible pathogenic role of melatonin neurotransmission in delirium.

Background and PurposeDementia with Lewy bodies (DLB) needs to be distinguished from Alzheimer’s disease (AD) because of important differences in patient management and outcome. Severe cardiac sympathetic degeneration occurs in DLB, but not in AD, offering a potential system for a biological diagnostic marker. The primary aim of this study was to investigate the diagnostic accuracy, in the ante-mortem differentiation of probable DLB from probable AD, of cardiac imaging with the ligand 123I-meta-iodobenzylguanidine (MIBG) which binds to the noradrenaline reuptake site, in the first multicenter study.MethodsWe performed a multicenter study in which we used 123I-MIBG scans to assess 133 patients with clinical diagnoses of probable (n = 61) or possible (n = 26) DLB or probable AD (n = 46) established by a consensus panel. Three readers, unaware of the clinical diagnosis, classified the images as either normal or abnormal by visual inspection. The heart-to-mediastinum ratios of 123I-MIBG uptake were also calculated using an automated region-of-interest based system.ResultsUsing the heart-to-mediastinum ratio calculated with the automated system, the sensitivity was 68.9% and the specificity was 89.1% to differentiate probable DLB from probable AD in both early and delayed images. By visual assessment, the sensitivity and specificity were 68.9% and 87.0%, respectively. In a subpopulation of patients with mild dementia (MMSE ≥ 22, n = 47), the sensitivity and specificity were 77.4% and 93.8%, respectively, with the delayed heart-to-mediastinum ratio.ConclusionsOur first multicenter study confirmed the high correlation between abnormal cardiac sympathetic activity evaluated with 123I-MIBG myocardial scintigraphy and a clinical diagnosis of probable DLB. The diagnostic accuracy is sufficiently high for this technique to be clinically useful in distinguishing DLB from AD, especially in patients with mild dementia.

Infected cells recognize viral replication as a DNA damage stress and elicit the ataxia telangiectasia-mutated (ATM)/p53-mediated DNA damage response signal transduction pathway as part of the host surveillance mechanisms, which ultimately induces the irreversible cell cycle arrest and apoptosis. Viruses have evolved a variety of mechanisms to counteract this host intracellular innate immunity. Kaposi's sarcoma-associated herpesvirus (KSHV) viral interferon regulatory factor 1 (vIRF1) interacts with the cellular p53 tumor suppressor through its central DNA binding domain, and this interaction inhibits transcriptional activation of p53. Here, we further demonstrate that KSHV vIRF1 downregulates the total p53 protein level by facilitating its proteasome-mediated degradation. Detailed biochemical study showed that vIRF1 interacted with cellular ATM kinase through its carboxyl-terminal transactivation domain and that this interaction blocked the activation of ATM kinase activity induced by DNA damage stress. As a consequence, vIRF1 expression greatly reduced the level of serine 15 phosphorylation of p53, resulting in an increase of p53 ubiquitination and thereby a decrease of its protein stability. These results indicate that KSHV vIRF1 comprehensively compromises an ATM/p53-mediated DNA damage response checkpoint by targeting both upstream ATM kinase and downstream p53 tumor suppressor, which might circumvent host growth surveillance and facilitate viral replication in infected cells.To prevent the fixation of mutations from one cell generation to the next and also maintain genomic stability, cells have evolved regulatory mechanisms that ensure the order and fidelity of cell cycle events, such as DNA replication and cell division. This regulatory mechanism becomes activated when cells are exposed to genotoxic agents or other adverse environmental conditions such as viral infection (reviewed in reference 38). The ataxia telangiectasia-mutated (ATM) and ataxia telangiectasia-and Rad3-related (ATR) kinases, both of which are phosphoinositide 3-kinase-related kinases, are critical for transducing DNA damage signals to checkpoint control proteins (51). ATM is essential for mediating cell cycle checkpoint control in cells exposed to ionizing radiation and other agents that produce double-strand breaks in DNA (25). In contrast, ATR is activated by stalled replication forks and agents that produce bulky adducts, such as UV irradiation (45). Upon DNA damage signaling, activation of both kinases results in the direct or indirect phosphorylation or activation of a number of downstream checkpoint controls, DNA repair, or apoptosis-promoting targets, including p53, Chk1, and Chk2 (3,8,18,37,53). Chk1 and Chk2 become phosphorylated at serine 345 (34) and threonine 68 (37), respectively, following genotoxic exposure. The roles of Chk1 and Chk2 in response to DNA damage are essential, as inhibition of the ATM/Chk2 pathway results in a loss of the G 2 /M checkpoint and increased sensitivity to ionizing radiation, whereas Chk2 mutat...

Background The number of patients suffering from diabetic nephropathy resulting in end-stage kidney disease is increasing worldwide. In clinical settings, there are limited data regarding the impact of the urinary albumin-to-creatinine ratio (UACR) and reduced estimated glomerular filtration rate (eGFR) on renal and cardiovascular outcomes and all-cause mortality. Methods We performed a historical cohort study of 4328 Japanese participants with type 2 diabetes from 10 centers. Risks for renal events (requirement for dialysis or transplantation, or half reduction in eGFR), cardiovascular events (cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke), and all-cause mortality were assessed according to UACR and eGFR levels. Results During follow-up (median 7.0 years, interquartile range 3.0-8.0 years), 419 renal events, 605 cardiovascular events and 236 deaths occurred. The UACR levels increased the risk and the adjusted hazard ratios for these three events. In addition to the effects of UACR levels, eGFR stages significantly increased the adjusted hazard ratios for renal events and all-cause mortality, especially in 123Clin Exp Nephrol DOI 10.1007/s10157-013-0879-4 patients with macroalbuminuria. Diabetic nephropathy score, based on the prognostic factors, well predicted incidence rates per 1000 patient/year for each event.Conclusions Increased UACR levels were closely related to the increase in risks for renal, cardiovascular events and all-cause mortality in Japanese patients with type 2 diabetes, whereas the association between high levels of UACR and reduced eGFR was a strong predictor for renal events.

Our objective was to determine whether the consumption of green tea, coffee, or black tea influences the incidence of dementia and mild cognitive impairment (MCI) in older people. We conducted a population-based prospective study with Japanese residents aged >60 years from Nakajima, Japan (the Nakajima Project). Participants received an evaluation of cognitive function and blood tests. The consumption of green tea, coffee, and black tea was also evaluated at baseline. Of 723 participants with normal cognitive function at a baseline survey (2007–2008), 490 completed the follow up survey in 2011–2013. The incidence of dementia during the follow-up period (mean ± SD: 4.9±0.9 years) was 5.3%, and that of MCI was 13.1%. The multiple-adjusted odds ratio for the incidence of overall cognitive decline (dementia or MCI) was 0.32 (95% CI: 0.16–0.64) among individuals who consumed green tea every day and 0.47 (95% CI: 0.25–0.86) among those who consumed green tea 1–6 days per week compared with individuals who did not consume green tea at all. The multiple-adjusted odds ratio for the incidence of dementia was 0.26 (95% CI: 0.06–1.06) among individuals who consumed green tea every day compared with those who did not consume green tea at all. No association was found between coffee or black tea consumption and the incidence of dementia or MCI. Our results indicate that green tea consumption is significantly associated with reduced risk of cognitive decline, even after adjustment for possible confounding factors.