Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).

Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and ≥1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (n = 5069) or prospectively (n = 5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (≤6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; p = 0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)

Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

A Pseudorabies Virus Recombinant Simultaneously Lacking the Major Tegument Proteins Encoded by the UL46, UL47, UL48, and UL49 Genes Is Viable in Cultured Cells

The UL46, UL47, UL48, and UL49 genes, which encode major tegument proteins, are conserved in most alphaherpesvirus genomes. However, the relative importance of each of these proteins for replication of individual alphaherpesviruses appears to be different. Recently, we demonstrated that single deletions of UL47 or UL48 impair maturation and egress of pseudorabies virus (PrV) particles to different extents, whereas deletions of UL46 or UL49 have no significant effects on virus replication in cell culture (W. Fuchs, H. Granzow, B. G. Klupp, M. Kopp, and T. C. Mettenleiter, J. Virol. 76:6729-6742, 2002; M. Kopp, B. G. Klupp, H. Granzow, W. Fuchs, and T. C. Mettenleiter, J. Virol. 76:8820-8833, 2002). To test for possible functional redundancy between the four tegument proteins, a quadruple gene deletion mutant (PrV-ΔUL46-49) was generated and characterized in vitro. Although plaque formation by this mutant was almost abolished and maximum titers were reduced more than 100-fold compared to those of parental wild-type virus, PrV-ΔUL46-49 could be propagated and serially passaged in noncomplementing porcine and rabbit kidney cells. Electron-microscopic studies revealed that nucleocapsid formation and egress of PrV-ΔUL46-49 from the host cell nucleus were not affected, but secondary envelopment of nucleocapsids in the cytoplasm was only rarely observed. The replication defect of PrV-ΔUL46-49 could be fully corrected by reinsertion of the UL46-to-UL49 gene cluster. Plaque sizes and virus titers were only slightly increased after restoration of only UL47 expression, whereas repair of only UL48 resulted in a significant increase in replication capacity to the level of a UL47 deletion mutant. In conclusion, we show that none of the UL46 to UL49 tegument proteins is absolutely required for productive replication of PrV. Moreover, our data indicate that the UL47 and UL48 proteins function independently during cell-to-cell spread and virus egress

Entry of Pseudorabies Virus: an Immunogold-Labeling Study

Herpesviruses infect cells by fusion of the viral envelope with cellular membranes, primarily the plasma membrane. During this process structural components of the mature virion are lost from the invading nucleocapsid, which then travels along microtubules to the nuclear pore. We examined the penetration process by immunoelectron microscopy and analyzed which of the major tegument proteins remained associated with the incoming capsid. We show that the UL36, UL37, and US3 proteins were present at intracytoplasmic capsids after penetration, whereas the UL11, UL47, UL48, and UL49 tegument proteins were lost. Thus, the three capsid-associated tegument proteins are prime candidates for viral proteins that interact with cellular motor proteins for transport of nucleocapsids to the nucleus

The UL49 gene product of BoHV-1: a major factor in efficient cell-to-cell spread

International audienceThe role of the UL49 gene product, VP22, of bovine herpesvirus type 1 (BoHV-1) in virus replication was characterized with respect to a putative functional interaction of VP22 with the viral glycoprotein E (gE) during BoHV-1 cell-to-cell spread. Deletion of the open reading frames of UL49 and/or gE from an infectious BoHV-1 bacterial artificial chromosome clone did not severely impair the production of viral progeny in single-step growth experiments. However, plaque sizes induced by a VP22-negative BoHV-1 were reduced by 52%, whilst for the gE/VP22-negative double-deletion mutant a reduction of 83% could be observed in comparison with parental and revertant viruses, which was consistent with a marked reduction in multi-step growth experiments at early time points. These results suggest that gE and VP22 are important for BoHV-1 cell-to-cell spread, and that both are likely to act independently of each other in a critical pathway for virus cell-to-cell spread

The Pseudorabies Virus US3 Protein Is a Component of Primary and of Mature Virions

Herpesviruses acquire a primary envelope by budding of capsids at the inner leaflet of the nuclear membrane. They then traverse into the cytoplasm after fusion of the primary envelope with the outer leaflet of the nuclear membrane. In the alphaherpesvirus pseudorabies virus (PrV), the latter process is impaired when the US3 protein is absent. Acquisition of final tegument and envelope occurs in the cytoplasm. Besides the capsid components, only the UL31 and UL34 gene products of PrV have unequivocally been shown to be part of primary enveloped virions, whereas they lack several tegument proteins present in mature virions (reviewed by T. C. Mettenleiter, J. Virol. 76:1537-1547, 2002). Using immunoelectron microscopy, we show that the US3 protein is present in primary enveloped as well as in mature virions. It is also detectable in intracytoplasmic inclusions produced in the absence of other viral tegument components or envelope-associated glycoproteins. In particular, inclusions formed in the absence of the inner tegument protein UL37 contained the US3 protein. Thus, the US3 protein is a tegument component of both forms of enveloped alphaherpes virions. We hypothesize that US3 protein in primary virions modulates deenvelopment at the outer leaflet of the nuclear membrane and is either lost from primary virions during nuclear egress and subsequently reacquired early during tegumentation or is retained during transit of the nucleocapsid through the nuclear membrane