Now showing items 21-40 of 2817

    • Learning from cubism to understand the reality of hemodynamics

      Stankiewicz, J.; Jeyaraju, M.; McCurdy, M.T. (BioMed Central Ltd., 2020)
    • Selective Naked-Eye Detection of SARS-CoV-2 Mediated by N Gene Targeted Antisense Oligonucleotide Capped Plasmonic Nanoparticles

      Moitra, P.; Alafeef, M.; Pan, D.; Frieman, M.B. (American Chemical Society, 2020)
      The current outbreak of the pandemic coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) demands its rapid, convenient, and large-scale diagnosis to downregulate its spread within as well as across the communities. But the reliability, reproducibility, and selectivity of majority of such diagnostic tests fail when they are tested either to a viral load at its early representation or to a viral gene mutated during its current spread. In this regard, a selective "naked-eye" detection of SARS-CoV-2 is highly desirable, which can be tested without accessing any advanced instrumental techniques. We herein report the development of a colorimetric assay based on gold nanoparticles (AuNPs), when capped with suitably designed thiol-modified antisense oligonucleotides (ASOs) specific for N-gene (nucleocapsid phosphoprotein) of SARS-CoV-2, could be used for diagnosing positive COVID-19 cases within 10 min from the isolated RNA samples. The thiol-modified ASO-capped AuNPs agglomerate selectively in the presence of its target RNA sequence of SARS-CoV-2 and demonstrate a change in its surface plasmon resonance. Further, the addition of RNaseH cleaves the RNA strand from the RNA-DNA hybrid leading to a visually detectable precipitate from the solution mediated by the additional agglomeration among the AuNPs. The selectivity of the assay has been monitored in the presence of MERS-CoV viral RNA with a limit of detection of 0.18 ng/?L of RNA having SARS-CoV-2 viral load. Thus, the current study reports a selective and visual "naked-eye" detection of COVID-19 causative virus, SARS-CoV-2, without the requirement of any sophisticated instrumental techniques.
    • A lipidome-wide association study of the lipoprotein insulin resistance index

      Bagheri, M.; O'connell, J.; Montasser, M. (Springer Nature, 2020)
      Background The lipoprotein insulin resistance (LPIR) score was shown to predict insulin resistance (IR) and type 2 diabetes (T2D) in healthy adults. However, the molecular basis underlying the LPIR utility for classification remains unclear. Objective To identify small molecule lipids associated with variation in the LPIR score, a weighted index of lipoproteins measured by nuclear magnetic resonance, in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) study (n = 980). Methods Linear mixed effects models were used to test the association between the LPIR score and 413 lipid species and their principal component analysis-derived groups. Significant associations were tested for replication with homeostatic model assessment-IR (HOMA-IR), a phenotype correlated with the LPIR score (r = 0.48, p <  0.001), in the Heredity and Phenotype Intervention (HAPI) Heart Study (n = 590). Results In GOLDN, 319 lipids were associated with the LPIR score (false discovery rate-adjusted p-values ranging from 4.59 × 10− 161 to 49.50 × 10− 3). Factors 1 (triglycerides and diglycerides/storage lipids) and 3 (mixed lipids) were positively (β = 0.025, p = 4.52 × 10− 71 and β = 0.021, p = 5.84 × 10− 41, respectively) and factor 2 (phospholipids/non-storage lipids) was inversely (β = − 0.013, p = 2.28 × 10− 18) associated with the LPIR score. These findings were replicated for HOMA-IR in the HAPI Heart Study (β = 0.10, p = 1.21 × 10− 02 for storage, β = − 0.13, p = 3.14 × 10− 04 for non-storage, and β = 0.19, p = 8.40 × 10− 07 for mixed lipids). Conclusions Non-storage lipidomics species show a significant inverse association with the LPIR metabolic dysfunction score and present a promising focus for future therapeutic and prevention studies.
    • A solitary erythematous papule on the nose

      Kabir, S.; Teimoorian, M.; Mahdavi, M. (Elsevier Inc, 2020)
    • BK Polyomavirus Evades Innate Immune Sensing by Disrupting the Mitochondrial Network and Promotes Mitophagy

      Manzetti, J.; Weissbach, F.H.; Drachenberg, C.B. (Elsevier Inc., 2020)
      Immune escape contributes to viral persistence, yet little is known about human polyomaviruses. BK-polyomavirus (BKPyV) asymptomatically infects 90% of humans but causes premature allograft failure in kidney transplant patients. Despite virus-specific T cells and neutralizing antibodies, BKPyV persists in kidneys and evades immune control as evidenced by urinary shedding in immunocompetent individuals. Here, we report that BKPyV disrupts the mitochondrial network and membrane potential when expressing the 66aa-long agnoprotein during late replication. Agnoprotein is necessary and sufficient, using its amino-terminal and central domain for mitochondrial targeting and network disruption, respectively. Agnoprotein impairs nuclear IRF3-translocation, interferon-beta expression, and promotes p62/SQSTM1-mitophagy. Agnoprotein-mutant viruses unable to disrupt mitochondria show reduced replication and increased interferon-beta expression but can be rescued by type-I interferon blockade, TBK1-inhibition, or CoCl2-treatment. Mitochondrial fragmentation and p62/SQSTM1-autophagy occur in allograft biopsies of kidney transplant patients with BKPyV nephropathy. JCPyV and SV40 infection similarly disrupt mitochondrial networks, indicating a conserved mechanism facilitating polyomavirus persistence and post-transplant disease. Copyright 2020 The Author(s)
    • A lipomatous, cervicothoracic mass causing tracheal compression in a child

      Moore, M.C.; Patel, L.; Parikh, R.B.; Lumpkins, K.; Englum, B.R. (Elsevier Inc., 2020)
      Lipomatous lesions in children are significantly less common than in the adult population and tend to occur subcutaneously on the trunk or extremities. When they are found in the thorax, these lesions are more likely to be in the anterior mediastinum. Although pediatric lipomatous tumors are typically benign and slow-growing, mass effect can be seen in small spaces and malignancy remains a real threat. A 5-year-old male presented with an asymptomatic left neck mass, which was seen on imaging to extend from the visceral space of the neck into the posterior mediastinum to the level of the carina, causing tracheal deviation and compression. The mass was excised in its entirety and found to be a benign lipoma. Imaging is important to determine the exact location and interaction of the mass with cervical and mediastinal structures. Excision of the entire mass is the optimal treatment in order to make a definitive diagnosis, prevent complications from compression of mediastinal structures, and avoid recurrence. Copyright 2020 The Authors
    • Next-generation rotavirus vaccines: important progress but work still to be done

      Bines, J.E.; Kotloff, K.L. (Lancet Publishing Group, 2020)
    • Personality and local brain structure: Their shared genetic basis and reproducibility

      Valk, S.L.; Hoffstaedter, F.; Kochunov, P. (Academic Press Inc., 2020)
      Local cortical architecture is highly heritable and distinct genes are associated with specific cortical regions. Total surface area has been shown to be genetically correlated with complex cognitive capacities, suggesting cortical brain structure is a viable endophenotype linking genes to behavior. However, to what extend local brain structure has a genetic association with cognitive and emotional functioning is incompletely understood. Here, we study the genetic correlation between personality traits and local cortical structure in a large-scale twin sample (Human Connectome Project, n ​= ​1102, 22-37y) and we evaluated whether observed associations reflect generalizable relationships between personality and local brain structure two independent age-matched samples (Brain Genomics Superstructure Project: n ​= ​925, age ​= ​19-35y, enhanced Nathan Kline Institute dataset: n ​= ​209, age: 19-39y). We found a genetic overlap between personality traits and local cortical structure in 10 of 18 observed phenotypic associations in predominantly frontal cortices. However, we only observed evidence in favor of replication for the negative association between surface area in medial prefrontal cortex and Neuroticism in both replication samples. Quantitative functional decoding indicated this region is implicated in emotional and socio-cognitive functional processes. In sum, our observations suggest that associations between local brain structure and personality are, in part, under genetic control. However, associations are weak and only the relation between frontal surface area and Neuroticism was consistently observed across three independent samples of young adults.
    • Effects of novel non-thermal atmospheric plasma treatment of titanium on physical and biological improvements and in vivo osseointegration in rats

      Zheng, Z.; Ao, X.; Xu, H.H.K. (Nature Research, 2020)
      Titanium (Ti) has achieved extensive applications due to its excellent biocompatibility and mechanical properties. Plasma can enhance surface hydrophilia of Ti with decreased carbon contamination. The traditional conditions using a single gas plasma was for longer treatment time and more prone to being contaminated. We designed and developed novel and universal apparatus and methods with a special clamping device of non-thermal atmospheric plasma (NTAP) treatment using mixed gas for Ti surface activation. We systematically and quantitatively investigated the effective effects of NTAP-Ti. The surface water contact angle decreased by 100%, the carbon content decreased by 80% and oxygen content increased by 50% in the novel NTAP-Ti surfaces. NTAP treatment accelerated the attachment, spread, proliferation, osteogenic differentiation and mineralization of MC3T3-E1 mouse preosteoblasts in vitro. The percentage of bone-to-implant contact increased by 25-40%, and the osteoclasts and bone resorption were suppressed by 50% in NTAP-Ti in vivo. In conclusion, NTAP-Ti substantially enhanced the physical and biological effects and integration with bone. The novel and universal apparatus and methods with a special clamping device using gas mixtures are promising for implant activation by swiftly and effectively changing the Ti surface to a hydrophilic one to enhance dental and orthopedic applications. Copyright 2020, The Author(s).
    • Associations Between Cardiac Biomarkers and Cardiac Structure and Function in CKD

      Christenson, R.H.; Seliger, S.L.; CRIC Study Investigators (Elsevier Inc, 2020)
      Introduction: Subclinical changes to cardiac structure and function detected with echocardiography precede the development of clinical heart failure (HF) in persons with chronic kidney disease (CKD). Circulating cardiac biomarkers may reflect these pathophysiological changes. This study investigated associations between established biomarkers (N-terminal pro-B-type natriuretic peptide [NT-proBNP] and high-sensitivity troponin T [hsTnT]) and novel biomarkers (growth differentiation factor 15 [GDF-15], galectin-3 [Gal-3], and soluble ST-2 [sST-2]), using echocardiographic measurements in persons with CKD. Methods: In cross-sectional analyses among 2101 participants with mild to moderate CKD in the Chronic Renal Insufficiency Cohort (CRIC), biomarker levels measured at baseline were evaluated with echocardiographic measurements 1 year later. These included left ventricular mass index (LVMI), left ventricular end-systolic volume (LVESV), left ventricular end-diastolic volume (LVEDV), left ventricular ejection fraction (LVEF), and left atrial diameter (LAD). Multivariable linear regression analyses tested associations of each biomarker with echocardiographic measurements, adjusting for covariates. Results: GDF-15 was significantly associated with higher LVMI (1.0 g/m2.7; 95% CI, 0.4-1.7), LVESV (0.4 ml/m2.7; 95% CI, 0.0-0.7), and LVEDV (0.6 ml/m2.7; 95% CI, 0.1-1.1), but not with LVEF or LAD. These findings were not significant when adjusting for NT-proBNP and hsTnT. Gal-3 and sST-2 had no significant associations. Higher levels of NT-proBNP and hsTnT were associated with all echocardiographic measurements. Conclusion: In patients with CKD, the novel biomarker GDF-15, a marker of inflammation and tissue injury, and clinical biomarkers NT-proBNP and hsTnT, were associated with echocardiographic measurements of subclinical cardiovascular disease. Collectively, these biomarkers may highlight biological pathways that contribute to the development of clinical HF.
    • Hsp60 Post-translational Modifications: Functional and Pathological Consequences

      Conway de Macario, E.; Bavisotto, C.C.; Marcario, A.J.L. (Frontiers Media S.A., 2020)
      Hsp60 is a chaperone belonging to the Chaperonins of Group I and typically functions inside mitochondria in which, together with the co-chaperonin Hsp10, maintains protein homeostasis. In addition to this canonical role, Hsp60 plays many others beyond the mitochondria, for instance in the cytosol, plasma-cell membrane, extracellular space, and body fluids. These non-canonical functions include participation in inflammation, autoimmunity, carcinogenesis, cell replication, and other cellular events in health and disease. Thus, Hsp60 is a multifaceted molecule with a wide range of cellular and tissue locations and functions, which is noteworthy because there is only one hsp60 gene. The question is by what mechanism this protein can become multifaceted. Likely, one factor contributing to this diversity is post-translational modification (PTM). The amino acid sequence of Hsp60 contains many potential phosphorylation sites, and other PTMs are possible such as O-GlcNAcylation, nitration, acetylation, S-nitrosylation, citrullination, oxidation, and ubiquitination. The effect of some of these PTMs on Hsp60 functions have been examined, for instance phosphorylation has been implicated in sperm capacitation, docking of H2B and microtubule-associated proteins, mitochondrial dysfunction, tumor invasiveness, and delay or facilitation of apoptosis. Nitration was found to affect the stability of the mitochondrial permeability transition pore, to inhibit folding ability, and to perturb insulin secretion. Hyperacetylation was associated with mitochondrial failure; S-nitrosylation has an impact on mitochondrial stability and endothelial integrity; citrullination can be pro-apoptotic; oxidation has a role in the response to cellular injury and in cell migration; and ubiquitination regulates interaction with the ubiquitin-proteasome system. Future research ought to determine which PTM causes which variations in the Hsp60 molecular properties and functions, and which of them are pathogenic, causing chaperonopathies. This is an important topic considering the number of acquired Hsp60 chaperonopathies already cataloged, many of which are serious diseases without efficacious treatment. Copyright 2020 The Authors.
    • Integrated urine proteomics and renal single-cell genomics identify an IFN-γ response gradient in lupus nephritis

      Zhang, Y.; Magder, L.; Accelerating Medicines Partnership in SLE network (The American Society for Clinical Investigation, 2020)
      Lupus nephritis, one of the most serious manifestations of systemic lupus erythematosus (SLE), has a heterogeneous clinical and pathological presentation. For example, proliferative nephritis identifies a more aggressive disease class that requires immunosuppression. However, the current classification system relies on the static appearance of histopathological morphology, which does not capture differences in the inflammatory response. Therefore, a biomarker grounded in the disease biology is needed in order to understand the molecular heterogeneity of lupus nephritis and identify immunologic mechanism and pathways. Here, we analyzed the patterns of 1000 urine protein biomarkers in 30 patients with active lupus nephritis. We found that patients stratify over a chemokine gradient inducible by IFN-γ. Higher values identified patients with proliferative lupus nephritis. After integrating the urine proteomics with the single-cell transcriptomics of kidney biopsies, we observed that the urinary chemokines defining the gradient were predominantly produced by infiltrating CD8+ T cells, along with natural killer and myeloid cells. The urine chemokine gradient significantly correlated with the number of kidney-infiltrating CD8+ cells. These findings suggest that urine proteomics can capture the complex biology of the kidney in lupus nephritis. Patient-specific pathways could be noninvasively tracked in the urine in real time, enabling diagnosis and personalized treatment.
    • The Nucleocapsid Protein of SARS-CoV-2: a Target for Vaccine Development

      Dutta, N.K.; Mazumdar, K.; Gordy, J.T. (American Society for Microbiology, 2020)
    • COVID-19 Pandemic Hemoperfusion Therapy Versus Plasma Exchange Therapy in Intensive Care

      Moayedi, S.; Golitaleb, M.; Vardanjani, A.E. (Tehran University of Medical Sciences, 2020)
    • Factor VIII and Functional Protein C Activity in Critically Ill Patients With Coronavirus Disease 2019: A Case Series

      Tabatabai, A.; Rabin, J.; Menaker, J.; Madathil, R.; Galvagno, S.; Menne, A.; Chow, J.H.; Herr, D.; Tanaka, K.; Scalea, T.; et al. (Wolters Kluwer Health, 2020)
      Critically ill patients with coronavirus disease 2019 (COVID-19) have been observed to be hypercoagulable, but the mechanisms for this remain poorly described. Factor VIII is a procoagulant factor that increases during inflammation and is cleaved by activated protein C. To our knowledge, there is only 1 prior study of factor VIII and functional protein C activity in critically ill patients with COVID-19. Here, we present a case series of 10 critically ill patients with COVID-19 who had severe elevations in factor VIII activity and low normal functional protein C activity, which may have contributed to hypercoagulability.
    • Influenza or Meningococcal Immunization During Pregnancy and Mortality in Women and Infants: A Pooled Analysis of Randomized Controlled Trials

      Clark, D.R.; Tapia, M.D.; for BMGF Supported Maternal Influenza Immunization Trials Investigators Group (Wolters Kluwer Health, 2020)
      This analysis includes pooled data from 2 placebo-controlled maternal influenza immunization trials, with a separate analysis on a meningococcal conjugate vaccine-controlled maternal influenza immunization trial. Maternal influenza immunization was not associated with infant or maternal all-cause mortality in placebo-controlled trials. In the meningococcal conjugate vaccine-controlled trial, there were fewer deaths during low or any influenza circulation weeks among infants whose mothers received meningococcal conjugate vaccine. ClinicalTrials.gov identifiers: NCT01430689, NCT01034254 and NCT02465190.
    • Role of Pyroptosis in Traumatic Brain and Spinal Cord Injuries

      Hu, X.; Chen, H.; Xu, H. (Ivyspring International Publisher, 2020)
      Central nervous system (CNS) trauma, including traumatic brain injury (TBI) and spinal cord injury (SCI), remains a leading cause for morbidity and mortality worldwide. Past research has shown that cell death plays a critical role in the pathophysiology of CNS injuries. More recently, pyroptosis has been identified as a form of programmed inflammatory cell death, and it is a unique form of cell death in various aspects. Mechanistically, pyroptosis can be categorized into canonical (mediated by caspase-1) and non-canonical (mediated by caspase-4/5/11). In canonical pyroptosis, Nod-like receptors (NLRs) inflammasomes play a critical role, and their activation promotes the maturation and secretion of the inflammatory cytokines interleukin-1?/18 (IL-1?/18), cleavage of gasdermin D (GSDMD), and ultimately pyroptotic cell death. Despite a plethora of new knowledge regarding pyroptosis, detailed understanding of how pyroptosis is involved in CNS injuries and possible ways to improve clinical outcomes following CNS injuries remain elusive. This review discusses the current knowledge on how pyroptosis is involved in CNS injuries, focusing on new discoveries regarding how pyroptosis activation occurs, differences between CNS cell types following injury, time-course of inflammatory responses, and key regulatory steps of pyroptosis. In addition, we highlight various investigational agents that are capable of regulating key steps in pyroptotic cell death, and we discuss how these agents may be used as therapies to improve outcomes following CNS trauma. CopyrightThe author(s).
    • Modeling human pediatric and adult gliomas in immunocompetent mice through costimulatory blockade

      Lan, X.; Chu, C.; Jablonska, A.; Liang, Y.; Janowski, M.; Walczak, P. (Taylor and Francis Inc., 2020)
      Currently, human glioma tumors are mostly modeled in immunodeficient recipients; however, lack of interactions with adaptive immune system is a serious flaw, particularly in the era when immunotherapies dominate treatment strategies. Our group was the first to successfully establish the orthotopic transplantation of human glioblastoma (GBM) in immunocompetent mice by inducing immunological tolerance using a short-term, systemic costimulation blockade strategy (CTLA-4-Ig and MR1). In this study, we further validated the feasibility of this method by modeling pediatric diffuse intrinsic pontine glioma (DIPG) and two types of adult GBM (GBM1, GBM551), in mice with intact immune systems and immunodeficient mice. We found that all three glioma models were successfully established, with distinct difference in tumor growth patterns and morphologies, after orthotopic xenotransplantation in tolerance-induced immunocompetent mice. Long-lasting tolerance that is maintained for up to nearly 200 d in GBM551 confirmed the robustness of this model. Moreover, we found that tumors in immunocompetent mice displayed features more similar to the clinical pathophysiology found in glioma patients, characterized by inflammatory infiltration and strong neovascularization, as compared with tumors in immunodeficient mice. In summary, we have validated the robustness of the costimulatory blockade strategy for tumor modeling and successfully established three human glioma models including the pediatric DIPG whose preclinical study is particularly thwarted by the lack of proper animal models. Copyright 2020 the Author(s).