Predictors of vertigo in the emergency department: The preved study.

BACKGROUND AND PURPOSE: Acute vertigo (sense of motion) can be the sole manifestation of a posterior circulation stroke, and often gets missed in the emergency department (ED). The studies for evaluation of central vertigo have focused on physical exam findings, which require expertise and may not be suitable for rapid triage by a nurse in ED or by paramedics. METHODS: This cross sectional study included retrospective chart review of patients 18 years of age and older who presented to the Adult ED with acute dizziness or vertigo during the calendar year 2017. All the patients with a diagnosis of central or peripheral vertigo were included in the final analysis. Sensitivity, specificity, Likelihood Ratio of positive result (LR (+)) and Likelihood Ratio of negative result (LR (-)) for central and peripheral vertigo were calculated for risk factors, symptoms and physical examination features. Chi-squared test and univariate logistic regression were used to evaluate statistical correlation and to calculate the prevalence odds ratio (POR). RESULTS: Two hundred and forty nine out of 505 (49.3%) patients presenting with dizziness had vertigo. Of these, 14 had central vertigo and 163 had peripheral vertigo. Statistically significant variables were: constant symptoms of vertigo (p 0.000- POR 8.7, 95% confidence interval (CI) 2.3-33.1), no change in symptoms with head movement (p 0.000- POR 10.2, 95% CI 3.0-35.4), dysmetria (p 0.000- POR 56.8, 95% CI 5.8-557.1), and unsteady gait (p 0.000- POR 13.3, 95% CI 3.3-54.3). The sensitivity and specificity to detect central vertigo were 100% and 66.4% respectively if the patient had either unsteady gait, constant symptoms, or no change in symptoms with head movement, [VAIN triad (Vertigo- Ataxia, Incessant, or Non-positional)]. CONCLUSIONS: We suggest that triage with VAIN triad can be used to design prospective studies to develop a triage algorithm for the detection of central vertigo in the ED.

AcMNPV PKIP is required for hyperexpression of very late genes and involved in the hyperphosphorylation of the viral basic protein P6.9.

A previous study showed that a mutation in Autographa californica multiple nucleopolyhedrovirus pkip (ac24) led to severe defects in progeny budded virion production and very late gene transcription at non-permissive temperature. To dissect the underlying mechanism, our early study showed that PKIP is associated with nucleocapsid of budded virion and involved in nucleocapsid assembly. However, how pkip affects very late gene transcription has not been determined. In the present study, double-stranded RNA was used to silence pkip expression during virus infection, resulting in the significant reduction of occlusion body production and polyhedrin expression. To find out whether PKIP regulates polyhedrin expression by affecting the transcription of other viral genes for very late gene expression, a comparative transcriptome analysis of viral genes was performed by RNA sequencing and the result showed that silencing pkip specifically down-regulated transcription of very late genes, while the transcription patterns of the viral genes associated with very late gene transcription were not affected. Since PKIP was reported to interact with and stimulate the activity of virus-encoded protein kinase PK1 and PK1 was involved in the hyperphosphorylation of viral basic protein P6.9, which was required for the maximal hyperexpression of very late genes, we sought to determine the association between PKIP and P6.9. Further experiments showed that PKIP interacted with P6.9 during virus infection, and the deletion of pkip resulted in decreased hyperphosphorylation of P6.9. Taken together, our results indicated that PKIP is involved in hyperphosphorylation of P6.9, which in return maybe required for hyperexpression of very late genes.

Prevalence and Predictors of Deep Vein Thrombosis in Critically Ill Medical Patients Who Underwent Diagnostic Duplex Ultrasonography.

INTRODUCTION: Deep vein thrombosis (DVT) is a recognized but preventable cause of morbidity and mortality in the medical intensive care unit (MICU). We examined the prevalence and risk factors for DVT in MICU patients who underwent diagnostic venous duplex ultrasonography (DUS) and the potential effect on clinical outcomes. METHODS: This is a retrospective study examining prevalence of DVT in 678 consecutive patients admitted to a tertiary care level academic MICU from July 2014 to 2015. Patients who underwent diagnostic DUS were included. Potential conditions of interest were mechanical ventilation, hemodialysis, sepsis, Sequential Organ Failure Assessment (SOFA) scores, central venous catheters, prior DVT, and malignancy. Primary outcomes were pulmonary embolism, ICU length of stay, and mortality. Additionally, means of thromboprophylaxis was compared between the groups. Multivariable logistic regression analysis was utilized to determine predictors of DVT occurrence. RESULTS: Of the 678 patients, 243 (36%) patients underwent DUS to evaluate for DVT. The prevalence of DVT was 16% (38) among tested patients, and a prior history of DVT was associated with DVT prevalence (P < .01). Between cases and controls, there were no significant differences in central venous catheters, mechanical ventilation, hemodialysis, sepsis, SOFA scores, malignancy, and recent surgery. Patients receiving chemical prophylaxis had fewer DVTs compared to persons with no prophylaxis (14% vs 29%; P = .01) and persons with dual chemical and mechanical prophylaxis (P = 0.1). Fourteen percent of patients tested had documented DVT while on chemoprophylaxis. There were no significant differences in ICU length of stay (P = .35) or mortality (P = .34). CONCLUSIONS: Despite the appropriate use of universal thromboprophylaxis, critically ill nonsurgical patients still demonstrated high rates of DVT. A history of DVT was the sole predictor for development of proximal DVT on DUS testing. Dual chemical and mechanical prophylaxis does not appear to be superior to single-chemical prophylaxis in DVT prevention in this population.

AcMNPV PKIP is associated with nucleocapsid of budded virions and involved in nucleocapsid assembly.

Autographa californica multiple nucleopolyhedrovirus (AcMNPV) orf24 (pkip) is a unique Alphabaculovirus gene. A previous study showed that a temperature-sensitive mutant of AcMNPV with a mutation in pkip displayed severe defects in progeny budded virion (BV) production and very late gene transcription, however, the underlying mechanism has not been determined. To investigate the function of pkip in the baculovirus replication cycle, we constructed a pkip-knockout AcMNPV bacmid in this study. Our results showed that deletion of pkip led to significant reduction of BV production, while the synthesis of viral DNA and the transcription of early and late genes were not affected. Further examination by transmission electron microscopy analysis showed that deletion of pkip resulted in the formation of massive electron-lucent tubular structures in the nucleus of the infected cells, along with some normal electron-dense nucleocapsids. The pkip-encoded protein PKIP could be detected at late phase during infection and was distributed in both the cytoplasm and nuclei of viruses-infected cells, with a ring pattern near the inner nuclear membrane and punctate distribution in the virogenic stroma area. Biochemical fractionation of virions into nucleocapsid and envelop components showed that PKIP was associated with the nucleocapsid fraction of BV. Taken together, our results indicated that PKIP is associated with nucleocapsids of BV and involved in nucleocapsid assembly, which contributes to the optimal production of BV.

The 38K-Mediated Specific Dephosphorylation of the Viral Core Protein P6.9 Plays an Important Role in the Nucleocapsid Assembly of Autographa californica Multiple Nucleopolyhedrovirus.

Encapsidation of the viral genomes, leading to the assembly of the nucleocapsids to form infectious progeny virions, is a key step in many virus life cycles. Baculovirus nucleocapsid assembly is a complex process that involves many proteins. Our previous studies showed that the deletion of the core gene 38K (ac98) interrupted the nucleocapsid assembly by producing capsid sheaths devoid of viral genomes by an unknown mechanism. All homologs of 38K contain conserved motifs of the haloacid dehalogenase superfamily, which are involved in phosphoryl transfer. The requirements of these motifs for nucleocapsid assembly, confirmed in the present study, suggest that 38K may be a functioning haloacid dehalogenase. P6.9 is also encoded by a core gene (ac100) and is required for viral genome encapsidation. It has been reported that multiple phosphorylated species of P6.9 are present in virus-infected cells, while only an unphosphorylated species is detected in the budded virus. Therefore, whether 38K mediates the dephosphorylation of P6.9 was investigated. An additional phosphorylated species of P6.9 in 38K-deleted or -mutated virus-transfected cells was detected, and the dephosphorylated sites mediated by 38K were determined by mass spectrometry. To assess the effects of dephosphorylation of P6.9 mediated by 38K on virus replication, these sites were mutated to glutamic acids (phosphorylation-mimic mutant) or to alanines (phosphorylation-deficient mutant). Studies showed that the nucleocapsid assembly was interrupted in phosphorylation-mimic mutant virus-transfected cells. Taken together, our findings demonstrate that 38K mediates the dephosphorylation of specific sites at the C terminus of P6.9, which is essential for viral genome encapsidation.IMPORTANCE Genome packaging is a fundamental process in the virus life cycle, and viruses have different strategies to perform this step. For several double-stranded DNA (dsDNA) viruses, the procapsid is formed before genome encapsidation, which may require basic proteins that help to neutralize the nucleic acid charge repulsion to facilitate the compaction of the genome within the confined capsid space. Baculovirus encodes a small basic protein, P6.9, which is required for a variety of processes in the virus infection cycle. The phosphorylation of P6.9 is thought to result in nucleocapsid uncoating, while the dephosphorylation of P6.9 is involved in viral DNA encapsidation during nucleocapsid assembly. Here, we demonstrate that a haloacid dehalogenase homolog encoded by baculovirus core gene 38K is involved in nucleocapsid assembly by mediating the dephosphorylation of 5 specific sites at the C terminus of P6.9. This finding contributes to the understanding of the mechanisms of virus nucleocapsid assembly.

Posttranslational Modifications of Baculovirus Protamine-Like Protein P6.9 and the Significance of Its Hyperphosphorylation for Viral Very Late Gene Hyperexpression.

UNLABELLED: Many viruses utilize viral or cellular chromatin machinery for efficient infection. Baculoviruses encode a conserved protamine-like protein, P6.9. This protein plays essential roles in various viral physiological processes during infection. However, the mechanism by which P6.9 regulates transcription remains unknown. In this study, 7 phosphorylated species of P6.9 were resolved in Sf9 cells infected with the baculovirus type species Autographa californica multiple nucleopolyhedrovirus (AcMNPV). Mass spectrometry identified 22 phosphorylation and 10 methylation sites but no acetylation sites in P6.9. Immunofluorescence demonstrated that the P6.9 and virus-encoded serine/threonine kinase PK1 exhibited similar distribution patterns in infected cells, and coimmunoprecipitation confirmed the interaction between them. Upon pk1 deletion, nucleocapsid assembly and polyhedron formation were interrupted and the transcription of viral very late genes was downregulated. Interestingly, we found that the 3 most phosphorylated P6.9 species vanished from Sf9 cells transfected with the pk1 deletion mutant, suggesting that PK1 is involved in the hyperphosphorylation of P6.9. Mass spectrometry suggested that the phosphorylation of the 7 Ser/Thr and 5 Arg residues in P6.9 was PK1 dependent. Replacement of the 7 Ser/Thr residues with Ala resulted in a P6.9 phosphorylation pattern similar to that of the pk1 deletion mutant. Importantly, the decreases in the transcription level of viral very late genes and viral infectivity were consistent. Our findings reveal that P6.9 hyperphosphorylation is a precondition for the maximal hyperexpression of baculovirus very late genes and provide the first experimental insights into the function of the baculovirus protamine-like protein and the related protein kinase in epigenetics. IMPORTANCE: Diverse posttranslational modifications (PTMs) of histones constitute a code that creates binding platforms that recruit transcription factors to regulate gene expression. Many viruses also utilize host- or virus-induced chromatin machinery to promote efficient infections. Baculoviruses encode a protamine-like protein, P6.9, which is required for a variety of processes in the infection cycle. Currently, P6.9's PTM sites and its regulating factors remain unknown. Here, we found that P6.9 could be categorized as unphosphorylated, hypophosphorylated, and hyperphosphorylated species and that a virus-encoded serine/threonine kinase, PK1, was essential for P6.9 hyperphosphorylation. Abundant PTM sites on P6.9 were identified, among which 7 Ser/Thr phosphorylated sites were PK1 dependent. Mutation of these Ser/Thr sites reduced very late viral gene transcription and viral infectivity, indicating that the PK1-mediated P6.9 hyperphosphorylation contributes to viral proliferation. These data suggest that a code exists in the sophisticated PTM of viral protamine-like proteins and participates in viral gene transcription.

Predictors for mortality in patients with antineutrophil cytoplasmic autoantibody-associated vasculitis: a study of 398 Chinese patients.

OBJECTIVE: Patients with antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV) have high mortality despite the introduction of immunosuppressive therapy. We investigated factors associated with mortality of patients with AAV in a single Chinese cohort. METHODS: A total of 398 consecutive patients with AAV diagnosed in our center were recruited. Clinical and laboratory data were collected retrospectively. The predictive values of variables associated with mortality were analyzed. RESULTS: During followup of a median duration 25.5 months (range 1-196 mo), 135 out of 398 patients (33.9%) died, with 83 deaths within the first 12 months after diagnosis. Independent predictors of all-cause mortality were age (p < 0.001), secondary infection (p < 0.001), pulmonary involvement of AAV (p = 0.012), and initial renal function (p = 0.001). Secondary infection was the leading cause of death (53/153, 39.3%) during the first year after diagnosis, while cardiovascular event was the leading cause of death (15/53, 28.8%) after 12 months from diagnosis. Independent predictors of secondary infection were age (p = 0.002), initial renal function (p = 0.041), lymphocyte counts in the peripheral blood (p = 0.03), and underlying pulmonary involvement of AAV (p = 0.001). CONCLUSION: Secondary infection is the overall leading cause and independent predictor of death in patients diagnosed with AAV. Cardiovascular event is a major cause of death during the late followup. Prudent monitoring should be given to patients of advancing age with renal dysfunction to reduce adverse events, especially infectious complications.