ABSTRACT
Bacteriophage T7 single-stranded DNA-binding protein (gp2.5) binds to and protects transiently exposed regions of single-stranded DNA (ssDNA) while dynamically interacting with other proteins of the replication complex. We directly visualize fluorescently labelled T7 gp2.5 binding to ssDNA at the single-molecule level. Upon binding, T7 gp2.5 reduces the contour length of ssDNA by stacking nucleotides in a force-dependent manner, suggesting T7 gp2.5 suppresses the formation of secondary structure. Next, we investigate the binding dynamics of T7 gp2.5 and a deletion mutant lacking 21 C-terminal residues (gp2.5-Δ21C) under various template tensions. Our results show that the base sequence of the DNA molecule, ssDNA conformation induced by template tension, and the acidic terminal domain from T7 gp2.5 significantly impact on the DNA binding parameters of T7 gp2.5. Moreover, we uncover a unique template-catalyzed recycling behaviour of T7 gp2.5, resulting in an apparent cooperative binding to ssDNA, facilitating efficient spatial redistribution of T7 gp2.5 during the synthesis of successive Okazaki fragments. Overall, our findings reveal an efficient binding mechanism that prevents the formation of secondary structures by enabling T7 gp2.5 to rapidly rebind to nearby exposed ssDNA regions, during lagging strand DNA synthesis.
Subject(s)
Bacteriophage T7 , Viral Proteins , Bacteriophage T7/genetics , DNA/metabolism , DNA Replication , DNA, Single-Stranded/genetics , DNA, Single-Stranded/metabolism , Molecular Conformation , Viral Proteins/metabolismABSTRACT
Anti-cluster of differentiation (CD) 3 × α programmed death-ligand 1 (PD-L1) bispecific T-cell engager (BsTE)-bound T-cells (BsTE:T) are a promising new cancer treatment agent. However, the mechanisms of action of bispecific antibody-armed activated T-cells are poorly understood. Therefore, this study aimed to investigate the anti-tumor mechanism and efficacy of BsTE:T. The BsTE:T migration was assessed in vivo and in vitro using syngeneic and xenogeneic tumor models, flow cytometry, immunofluorescence staining, transwell migration assays, microfluidic chips, Exo View R100, western blotting, and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 technology. In murine B16 melanoma, MC38 colon cancer, and human multiple myeloma cells, BsTE:T exhibited superior tumor elimination relative to that of T-cells or BsTE alone. Moreover, BsTE:T migration into tumors was significantly enhanced owing to the presence of PD-L1 in tumor cells and secretion of PD-L1-containing exosomes. Furthermore, increased infiltration of CD44highCD62Llow effector memory CD8+ T-cells into tumors was closely associated with the anti-tumor effect of BsTE:T. Therefore, BsTE:T is an innovative potential anti-tumor therapy, and exosomal PD-L1 plays a crucial role both in vitro and in vivo in the anti-tumor activity of BsTE:T.
Subject(s)
Antibodies, Bispecific , B7-H1 Antigen , Exosomes , Animals , Antibodies, Bispecific/pharmacology , Antibodies, Bispecific/immunology , Exosomes/metabolism , Exosomes/immunology , Mice , B7-H1 Antigen/metabolism , B7-H1 Antigen/antagonists & inhibitors , Humans , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Mice, Inbred C57BL , Melanoma, Experimental/immunology , Melanoma, Experimental/therapy , CD3 Complex/immunology , CD3 Complex/metabolism , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/metabolism , Cell Line, Tumor , Female , Cell Movement , Xenograft Model Antitumor AssaysABSTRACT
The B cell response to Salmonella typhimurium (STm) occurs massively at extrafollicular sites, without notable germinal centers (GCs). Little is known in terms of its specificity. To expand the knowledge of antigen targets, we screened plasmablast (PB)-derived monoclonal antibodies (mAbs) for Salmonella specificity, using ELISA, flow cytometry, and antigen microarray. Only a small fraction (0.5%-2%) of the response appeared to be Salmonella-specific. Yet, infection of mice with limited B cell receptor (BCR) repertoires impaired the response, suggesting that BCR specificity was important. We showed, using laser microdissection, that somatic hypermutation (SHM) occurred efficiently at extrafollicular sites leading to affinity maturation that in turn led to detectable STm Ag-binding. These results suggest a revised vision of how clonal selection and affinity maturation operate in response to Salmonella. Clonal selection initially is promiscuous, activating cells with virtually undetectable affinity, yet SHM and selection occur during the extrafollicular response yielding higher affinity, detectable antibodies.
Subject(s)
B-Lymphocytes/immunology , Clonal Selection, Antigen-Mediated/immunology , Germinal Center/immunology , Salmonella typhimurium/immunology , Somatic Hypermutation, Immunoglobulin/immunology , Animals , Antibodies, Monoclonal/immunology , Clonal Selection, Antigen-Mediated/genetics , Immunoglobulin G/biosynthesis , Immunoglobulin G/immunology , Lymphocyte Activation/immunology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout , Receptors, Antigen, B-Cell/genetics , Receptors, Antigen, B-Cell/immunology , Salmonella Infections/immunology , Salmonella Infections/microbiology , Somatic Hypermutation, Immunoglobulin/genetics , Spleen/cytology , Spleen/immunologyABSTRACT
BACKGROUND: Liver transplantation (LT) patients appear to be more prone to neurological events compared to individuals undergoing other types of solid-organ transplantation. The aims of the present study were to analyze the prevalence of unruptured intracranial aneurysms (UIAs) in patients undergoing liver transplantation (LT) and to examine the perioperative occurrence of subarachnoid hemorrhage (SAH). Also, it intended to systematically identify the risk factors of SAH and hemorrhagic stroke (HS) within a year after LT and to develop a scoring system which involves distinct clinical features of LT patients. METHODS: Patients who underwent LT from January 2012 to March 2022 were analyzed. All included patients underwent neurovascular imaging within 6 months before LT. We conducted an analysis of prevalence and radiological features of UIA and SAH. The clinical factors that may have an impact on HS within one year of LT were also reviewed. RESULTS: Total of 3,487 patients were enrolled in our study after applying inclusion and exclusion criteria. The prevalence of UIA was 5.4%. The incidence of SAH and HS within one year following LT was 0.5% and 1.6%, respectively. We developed a scoring system based on multivariable analysis to predict the HS within 1-year after LT. The variables were a poor admission mental status, the diagnosis of UIA, serum ammonia levels, and Model for End-stage Liver Disease (MELD) scores. Our model showed good discrimination among the development (C index, 0.727; 95% confidence interval [CI], 0.635-0.820) and validation (C index, 0.719; 95% CI, 0.598-0.801) cohorts. CONCLUSION: The incidence of UIA and SAH was very low in LT patients. A poor admission mental status, diagnosis of UIA, serum ammonia levels, and MELD scores were significantly associated with the risk of HS within one year after LT. Our scoring system showed a good discrimination to predict the HS in LT patients.
Subject(s)
End Stage Liver Disease , Hemorrhagic Stroke , Intracranial Aneurysm , Liver Transplantation , Stroke , Subarachnoid Hemorrhage , Humans , Intracranial Aneurysm/diagnosis , Intracranial Aneurysm/epidemiology , Intracranial Aneurysm/surgery , Hemorrhagic Stroke/complications , Liver Transplantation/adverse effects , Ammonia , End Stage Liver Disease/complications , Severity of Illness Index , Subarachnoid Hemorrhage/diagnosis , Subarachnoid Hemorrhage/epidemiology , Subarachnoid Hemorrhage/etiology , Stroke/diagnosis , Stroke/epidemiology , Stroke/etiologyABSTRACT
The T7 primase-helicase plays a pivotal role in the replication of T7 DNA. Using affinity isolation of peptide-nucleic acid crosslinks and mass spectrometry, we identify protein regions in the primase-helicase and T7 DNA polymerase that form contacts with the RNA primer and DNA template. The contacts between nucleic acids and the primase domain of the primase-helicase are centered in the RNA polymerase subdomain of the primase domain, in a cleft between the N-terminal subdomain and the topoisomerase-primase fold. We demonstrate that residues along a beta sheet in the N-terminal subdomain that contacts the RNA primer are essential for phage growth and primase activity in vitro. Surprisingly, we found mutations in the primase domain that had a dramatic effect on the helicase. Substitution of a residue conserved in other DnaG-like enzymes, R84A, abrogates both primase and helicase enzymatic activities of the T7 primase-helicase. Alterations in this residue also decrease binding of the primase-helicase to ssDNA. However, mass photometry measurements show that these mutations do not interfere with the ability of the protein to form the active hexamer.
Subject(s)
Bacteriophage T7 , DNA Helicases , DNA Primase , DNA , Viral Proteins , Amino Acid Sequence , Bacteriophage T7/enzymology , DNA/metabolism , DNA Helicases/chemistry , DNA Helicases/metabolism , DNA Primase/chemistry , DNA Primase/genetics , DNA Primase/metabolism , Mutation , Viral Proteins/chemistry , Viral Proteins/metabolismABSTRACT
BACKGROUND: Recurrence is common in glioblastoma multiforme (GBM) because of the infiltrative, residual cells in the tumor margin. Standard therapy for GBM consists of surgical resection followed by chemotherapy and radiotherapy, but the median survival of GBM patients remains poor (~ 1.5 years). For recurrent GBM, anti-angiogenic treatment is one of the common treatment approaches. However, current anti-angiogenic treatment modalities are not satisfactory because of the resistance to anti-angiogenic agents in some patients. Therefore, we sought to identify novel prognostic biomarkers that can predict the therapeutic response to anti-angiogenic agents in patients with recurrent glioblastoma. METHODS: We selected patients with recurrent GBM who were treated with anti-angiogenic agents and classified them into responders and non-responders to anti-angiogenic therapy. Then, we performed proteomic analysis using liquid-chromatography mass spectrometry (LC-MS) with formalin-fixed paraffin-embedded (FFPE) tissues obtained from surgical specimens. We conducted a gene-ontology (GO) analysis based on protein abundance in the responder and non-responder groups. Based on the LC-MS and GO analysis results, we identified potential predictive biomarkers for anti-angiogenic therapy and validated them in recurrent glioblastoma patients. RESULTS: In the mass spectrometry-based approach, 4957 unique proteins were quantified with high confidence across clinical parameters. Unsupervised clustering analysis highlighted distinct proteomic patterns (n = 269 proteins) between responders and non-responders. The GO term enrichment analysis revealed a cluster of genes related to immune cell-related pathways (e.g., TMEM173, FADD, CD99) in the responder group, whereas the non-responder group had a high expression of genes related to nuclear replisome (POLD) and damaged DNA binding (ERCC2). Immunohistochemistry of these biomarkers showed that the expression levels of TMEM173 and FADD were significantly associated with the overall survival and progression-free survival of patients with recurrent GBM. CONCLUSIONS: The candidate biomarkers identified in our protein analysis may be useful for predicting the clinical response to anti-angiogenic agents in patients with recurred GBM.
Subject(s)
Brain Neoplasms , Glioblastoma , Humans , Glioblastoma/drug therapy , Glioblastoma/genetics , Glioblastoma/metabolism , Proteomics , Brain Neoplasms/drug therapy , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Neoplasm Recurrence, Local/genetics , Angiogenesis Inhibitors/pharmacology , Angiogenesis Inhibitors/therapeutic use , Biomarkers , Xeroderma Pigmentosum Group D ProteinABSTRACT
T cell effector functions can be elicited by noncognate stimuli, but the mechanism and contribution of this pathway to the resolution of intracellular macrophage infections have not been defined. Here, we show that CD4(+) T helper 1 (Th1) cells could be rapidly stimulated by microbe-associated molecular patterns during active infection with Salmonella or Chlamydia. Further, maximal stimulation of Th1 cells by lipopolysaccharide (LPS) did not require T-cell-intrinsic expression of toll-like receptor 4 (TLR4), interleukin-1 receptor (IL-1R), or interferon-γ receptor (IFN-γR) but instead required IL-18R, IL-33R, and adaptor protein MyD88. Innate stimulation of Th1 cells also required host expression of TLR4 and inflammasome components that together increased serum concentrations of IL-18. Finally, the elimination of noncognate Th1 cell stimulation hindered the resolution of primary Salmonella infection. Thus, the in vivo bactericidal capacity of Th1 cells is regulated by the response to noncognate stimuli elicited by multiple innate immune receptors.
Subject(s)
Immunity, Innate/immunology , Inflammasomes/metabolism , Signal Transduction , Th1 Cells/immunology , Toll-Like Receptors/metabolism , Animals , Bacterial Load/immunology , CD4 Antigens/immunology , Chlamydia/physiology , Flow Cytometry , Interleukin-18/metabolism , Mice , Mice, Inbred C57BL , Real-Time Polymerase Chain Reaction , Salmonella/physiology , Toll-Like Receptor 4/metabolismABSTRACT
The vast majority of intracellular protein targets are refractory toward small-molecule therapeutic engagement, and additional therapeutic modalities are needed to overcome this deficiency. Here, the identification and characterization of a natural product, WDB002, reveals a therapeutic modality that dramatically expands the currently accepted limits of druggability. WDB002, in complex with the FK506-binding protein (FKBP12), potently and selectively binds the human centrosomal protein 250 (CEP250), resulting in disruption of CEP250 function in cells. The recognition mode is unprecedented in that the targeted domain of CEP250 is a coiled coil and is topologically featureless, embodying both a structural motif and surface topology previously considered on the extreme limits of "undruggability" for an intracellular target. Structural studies reveal extensive protein-WDB002 and protein-protein contacts, with the latter being distinct from those seen in FKBP12 ternary complexes formed by FK506 and rapamycin. Outward-facing structural changes in a bound small molecule can thus reprogram FKBP12 to engage diverse, otherwise "undruggable" targets. The flat-targeting modality demonstrated here has the potential to expand the druggable target range of small-molecule therapeutics. As CEP250 was recently found to be an interaction partner with the Nsp13 protein of the SARS-CoV-2 virus that causes COVID-19 disease, it is possible that WDB002 or an analog may exert useful antiviral activity through its ability to form high-affinity ternary complexes containing CEP250 and FKBP12.
Subject(s)
Actinobacteria/genetics , Antiviral Agents/pharmacology , Genome, Bacterial , Macrolides/pharmacology , Protein Interaction Domains and Motifs/drug effects , Small Molecule Libraries/pharmacology , Tacrolimus Binding Protein 1A/chemistry , Tacrolimus Binding Protein 1A/metabolism , Actinobacteria/metabolism , Amino Acid Sequence , Antiviral Agents/chemistry , Antiviral Agents/metabolism , Autoantigens/genetics , Autoantigens/metabolism , Calcineurin/genetics , Calcineurin/metabolism , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Evolution, Molecular , HEK293 Cells , Humans , Macrolides/chemistry , Macrolides/metabolism , Models, Molecular , Protein Conformation , Sequence Homology , Sirolimus/chemistry , Sirolimus/metabolism , Small Molecule Libraries/chemistry , Small Molecule Libraries/metabolism , TOR Serine-Threonine Kinases/genetics , TOR Serine-Threonine Kinases/metabolismABSTRACT
PURPOSE: An anterior communicating artery is a common location for both ruptured and unruptured intracranial aneurysms, and microsurgery is sometimes necessary for their successful treatment. However, postoperative infarction should be considered during clipping due to the complex surrounding structures of anterior communicating artery aneurysms. This study aimed to evaluate the risk factors of postoperative infarction after surgical clipping of unruptured anterior communicating artery aneurysms and its clinical outcomes. METHODS: The data of patients who underwent microsurgical clipping of an unruptured anterior communicating artery aneurysm in our hospital between January 2008 and December 2020 were retrospectively analyzed. The patients' demographic data, anatomical features of the anterior communicating artery complex and aneurysm, surgical technique, characteristics of postoperative infarction, and its clinical course were evaluated. RESULTS: Notably, among 848 patients, 66 (7.8%) and 34 (4%) patients had radiologic and symptomatic infarctions, respectively. Univariate and multivariate logistic regression analyses showed that hypertension (odds ratio (OR), 1.99; [Formula: see text]), previous stroke (OR, 3.89; [Formula: see text]), posterior projection (OR, 5.58; [Formula: see text]), aneurysm size (OR, 1.17; optimal cut-off value, 6.14 mm; [Formula: see text]), and skull base-to-aneurysm distance (OR, 1.15; optimal cut-off value, 11.09 mm; [Formula: see text]) were associated with postoperative infarction. In the pterional approach, a closed A2 plane was an additional risk factor (OR, 1.88; [Formula: see text]). Infarction of the subcallosal and hypothalamic branches was significantly associated with symptomatic infarction ([Formula: see text]). CONCLUSION: Hypertension, previous stroke, posteriorly projecting aneurysms, aneurysm size, and highly positioned aneurysms are independent risk factors for postoperative infarction during surgical clipping of an unruptured anterior communicating artery aneurysm. Additionally, a closed A2 plane is an additional risk factor of postoperative infarction in patients undergoing clipping via the pterional approach.
Subject(s)
Aneurysm, Ruptured , Intracranial Aneurysm , Stroke , Humans , Intracranial Aneurysm/diagnostic imaging , Intracranial Aneurysm/surgery , Intracranial Aneurysm/complications , Retrospective Studies , Infarction/complications , Risk Factors , Stroke/complications , Aneurysm, Ruptured/diagnostic imaging , Aneurysm, Ruptured/surgery , Aneurysm, Ruptured/complications , Treatment OutcomeABSTRACT
BACKGROUND: Subarachnoid hemorrhage (SAH) patients have oxidative stress results in inflammation, tissue degeneration and neuronal damage. These deleterious effects cause aggravation of the perihematomal edema (PHE), vasospasm, and even hydrocephalus. We hypothesized that antioxidants may have a neuroprotective role in acute aneurysmal SAH (aSAH) patients. METHODS: We conducted a prospective, multicenter randomized (single blind) trial between January 2017 and October 2019, investigating whether antioxidants (acetylcysteine and selenium) have the potential to improve the neurologic outcome in aSAH patients. The antioxidant patient group received antioxidants of acetylcysteine (2,000 mg/day) and selenium (1,600 µg/day) intravenously (IV) for 14 days. These drugs were administrated within 24 hours of admission. The non-antioxidant patient group received a placebo IV. RESULTS: In total, 293 patients were enrolled with 103 patients remaining after applying the inclusion and exclusion criteria. No significant differences were observed in the baseline characteristics between the antioxidant (n = 53) and non-antioxidant (n = 50) groups. Among clinical factors, the duration of intensive care unit (ICU) stay was significantly shortened in patients who received antioxidants (11.2, 95% confidence interval [CI], 9.7-14.5 vs. 8.3, 95% CI, 6.2-10.2 days, P = 0.008). However, no beneficial effects were observed on radiological outcomes. CONCLUSION: In conclusion, antioxidant treatment failed to show the reduction of PHE volume, mid-line shifting, vasospasm and hydrocephalus in acute SAH patients. A significant reduction in ICU stay was observed but need more optimal dosing schedule and precise outcome targets are required to clarify the clinical impacts of antioxidants in these patients. TRIAL REGISTRATION: Clinical Research Information Service Identifier: KCT0004628.
Subject(s)
Hydrocephalus , Selenium , Subarachnoid Hemorrhage , Humans , Subarachnoid Hemorrhage/complications , Subarachnoid Hemorrhage/drug therapy , Acetylcysteine/therapeutic use , Selenium/therapeutic use , Prospective Studies , Single-Blind Method , Treatment Outcome , Hydrocephalus/etiology , Hydrocephalus/complicationsABSTRACT
The Light Detection and Ranging (LiDAR) sensor has become essential to achieving a high level of autonomous driving functions, as well as a standard Advanced Driver Assistance System (ADAS). LiDAR capabilities and signal repeatabilities under extreme weather conditions are of utmost concern in terms of the redundancy design of automotive sensor systems. In this paper, we demonstrate a performance test method for automotive LiDAR sensors that can be utilized in dynamic test scenarios. In order to measure the performance of a LiDAR sensor in a dynamic test scenario, we propose a spatio-temporal point segmentation algorithm that can separate a LiDAR signal of moving reference targets (car, square target, etc.), using an unsupervised clustering method. An automotive-graded LiDAR sensor is evaluated in four harsh environmental simulations, based on time-series environmental data of real road fleets in the USA, and four vehicle-level tests with dynamic test cases are conducted. Our test results showed that the performance of LiDAR sensors may be degraded, due to several environmental factors, such as sunlight, reflectivity of an object, cover contamination, and so on.
ABSTRACT
RATIONALE: Central nervous system has low vascular permeability by organizing tight junction (TJ) and limiting endothelial transcytosis. While TJ has long been considered to be responsible for vascular barrier in central nervous system, suppressed transcytosis in endothelial cells is now emerging as a complementary mechanism. Whether transcytosis regulation is independent of TJ and its dysregulation dominantly causes diseases associated with edema remain elusive. Dll4 signaling is important for various vascular contexts, but its role in the maintenance of vascular barrier in central nervous system remains unknown. OBJECTIVE: To find a TJ-independent regulatory mechanism selective for transcytosis and identify its dysregulation as a cause of pathological leakage. METHODS AND RESULTS: We studied transcytosis in the adult mouse retina with low vascular permeability and employed a hypertension-induced retinal edema model for its pathological implication. Both antibody-based and genetic inactivation of Dll4 or Notch1 induce hyperpermeability by increasing transcytosis without junctional destabilization in arterial endothelial cells, leading to nonhemorrhagic leakage predominantly in the superficial retinal layer. Endothelial Sox17 deletion represses Dll4 in retinal arteries, phenocopying Dll4 blocking-driven vascular leakage. Ang II (angiotensin II)-induced hypertension represses arterial Sox17 and Dll4, followed by transcytosis-driven retinal edema, which is rescued by a gain of Notch activity. Transcriptomic profiling of retinal endothelial cells suggests that Dll4 blocking activates SREBP1 (sterol regulatory element-binding protein 1)-mediated lipogenic transcription and enriches gene sets favorable for caveolae formation. Profiling also predicts the activation of VEGF (vascular endothelial growth factor) signaling by Dll4 blockade. Inhibition of SREBP1 or VEGF-VEGFR2 (VEGF receptor 2) signaling attenuates both Dll4 blockade-driven and hypertension-induced retinal leakage. CONCLUSIONS: In the retina, Sox17-Dll4-SREBP1 signaling axis controls transcytosis independently of TJ in superficial arteries among heterogeneous regulations for the whole vessels. Uncontrolled transcytosis via dysregulated Dll4 underlies pathological leakage in hypertensive retina and could be a therapeutic target for treating hypertension-associated retinal edema.
Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Blood-Retinal Barrier/metabolism , Calcium-Binding Proteins/metabolism , Hypertensive Retinopathy/metabolism , Transcytosis , Adaptor Proteins, Signal Transducing/genetics , Animals , Arteries/metabolism , Calcium-Binding Proteins/genetics , Caveolae/metabolism , Endothelial Cells/metabolism , HMGB Proteins/metabolism , Homeostasis , Mice , Mice, Inbred C57BL , Receptor, Notch1/genetics , Receptor, Notch1/metabolism , SOXF Transcription Factors/metabolism , Signal Transduction , Sterol Regulatory Element Binding Protein 1/metabolism , Tight Junctions/metabolism , Vascular Endothelial Growth Factor A/metabolism , Vascular Endothelial Growth Factor Receptor-2/metabolismABSTRACT
Posterior communicating artery (PCoA) aneurysm is common and sometimes requires microsurgery; however, as data on premammillary artery (PMA) infarction after clipping is scarce, we retrospectively reviewed cases of post-clipping PMA infarction to analyze incidence, independent risk factors of infarction, and anatomical considerations. Data from 569 consecutive patients who underwent microsurgical clipping for unruptured PCoA aneurysm between January 2008 and December 2020 were included. Patients were categorized into the normal or the PMA infarction group. Statistical analyses and comparisons between the two groups were used to determine the influence of various factors. The normal group included 515 patients while the PMA infarction group had 31. The mean length of hospital stay was significantly longer in the PMA infarction group (10.3 ± 9.1 days) than in the normal group (6.5 ± 6.4 days; p < 0.0001). The distribution of Glasgow Outcome Scale at discharge was significantly different between the two groups (p ≤ 0.0001) but was not so at 6 months after discharge (p = 0.0568). Multivariate logistic regression analysis identified aneurysm size (odds ratio [OR], 1.194; 95% confidence interval [CI], 1.08-1.32; p = 0.0005) and medial direction of aneurysm (OR, 4.615; 95% CI, 1.224-17.406; p = 0.0239) as independent risk factors of post-clipping PMA infarction. Surgeons must beware of PMA infarction after clipping of large aneurysms that are medial in direction. Intraoperative verification of the patency of the PCoA and the PMA from various angles using various intraoperative methods can reduce morbidity due to PMA infarction.
Subject(s)
Aneurysm, Ruptured , Intracranial Aneurysm , Aneurysm, Ruptured/surgery , Arteries , Humans , Infarction/etiology , Infarction/surgery , Intracranial Aneurysm/etiology , Intracranial Aneurysm/surgery , Microsurgery/adverse effects , Microsurgery/methods , Neurosurgical Procedures/methods , Retrospective Studies , Risk Factors , Treatment OutcomeABSTRACT
The volatile compounds and sensory profiles of 18 different types of distilled soju, chosen with regard to various raw materials and distillation methods (atmospheric vs. vacuum), were explored using headspace solid-phase microextraction (HS-SPME) with gas chromatography-mass spectrometry (GC-MS) and descriptive analysis. General chemical properties such as pH, total acidity (TA), total soluble solids (°Brix), and lactic acid concentration were also determined. A total of 56 volatile compounds, comprising 31 esters, 11 alcohols, 1 acid, 4 aldehydes, 3 ketones, and 6 miscellaneous compounds, were identified. From the principal component analysis (PCA) of the volatile data, samples made using atmospheric distillation such as MSO and PJU showed a clear difference from decompressed distillation samples. Based on the PCA of the sensory data, there was also a clear distinction between samples by their distillation method. To explore relationships among chemical, volatile, and sensory data sets, multiple factor analysis (MFA) was applied. Yeasty and earthy flavors showed a close relationship with 1-nonanol, octatonic acid, and longer-chain esters such as ethyl phenylacetate and ethyl tetradecanoate, and with chemical parameters such as TA, °Brix, and lactic acid.
Subject(s)
Solid Phase Microextraction , Volatile Organic Compounds , Esters/analysis , Gas Chromatography-Mass Spectrometry/methods , Lactic Acid/analysis , Republic of Korea , Solid Phase Microextraction/methods , Volatile Organic Compounds/analysisABSTRACT
Bacteriophage T7 encodes its own DNA polymerase, the product of gene 5 (gp5). In isolation, gp5 is a DNA polymerase of low processivity. However, gp5 becomes highly processive upon formation of a complex with Escherichia coli thioredoxin, the product of the trxA gene. Expression of a gp5 variant in which aspartate residues in the metal-binding site of the polymerase domain were replaced by alanine is highly toxic to E. coli cells. This toxicity depends on the presence of a functional E. coli trxA allele and T7 RNA polymerase-driven expression but is independent of the exonuclease activity of gp5. In vitro, the purified gp5 variant is devoid of any detectable polymerase activity and inhibited DNA synthesis by the replisomes of E. coli and T7 in the presence of thioredoxin by forming a stable complex with DNA that prevents replication. On the other hand, the highly homologous Klenow fragment of DNA polymerase I containing an engineered gp5 thioredoxin-binding domain did not exhibit toxicity. We conclude that gp5 alleles encoding inactive polymerases, in combination with thioredoxin, could be useful as a shutoff mechanism in the design of a bacterial cell-growth system.
Subject(s)
Bacteriophage T7 , DNA Replication , DNA, Viral , DNA-Directed DNA Polymerase , Escherichia coli Proteins , Escherichia coli , Thioredoxins , Bacteriophage T7/enzymology , Bacteriophage T7/genetics , DNA, Viral/biosynthesis , DNA, Viral/chemistry , DNA, Viral/genetics , DNA-Directed DNA Polymerase/chemistry , DNA-Directed DNA Polymerase/genetics , DNA-Directed DNA Polymerase/metabolism , Escherichia coli/enzymology , Escherichia coli/genetics , Escherichia coli/virology , Escherichia coli Proteins/chemistry , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Protein Domains , Thioredoxins/chemistry , Thioredoxins/genetics , Thioredoxins/metabolismABSTRACT
[Figure: see text].
Subject(s)
Acetylcysteine/pharmacology , Cerebral Hemorrhage/drug therapy , Free Radical Scavengers/therapeutic use , Selenium/pharmacology , Adult , Cerebral Hemorrhage/pathology , Female , Humans , Male , Middle Aged , Oxidative Stress/drug effects , Reactive Oxygen Species/antagonists & inhibitors , Treatment OutcomeABSTRACT
BACKGROUND AND PURPOSE: Cerebrovascular diseases are a leading cause of mortality after liver transplantation (LT). The prevalence of potentially hemorrhagic cerebrovascular diseases (HCVDs) that could cause a hemorrhagic stroke in patients with severe liver diseases has not been reported. We aimed to analyze the underlying prevalence of HCVDs that could lead to hemorrhagic strokes in LT recipients compared with that in previously healthy controls. METHODS: A retrospective study with 1,920 consecutive LT recipients and 24,681 adults who underwent a health checkup during the same period was conducted (January 2011-December 2016). The prevalence of cerebral aneurysms (CA), cerebral arteriovenous malformation (AVM), and cavernous malformation (CM) was evaluated using brain imaging, including computed tomography angiography, magnetic resonance imaging, magnetic resonance angiography, and digital subtraction angiography. RESULTS: The prevalence of CA and CM were 3.1% and 0.5%, respectively, in the LT group and 3.8% and 0.4%, respectively, in the control group. According to the location of the cerebral artery, paraclinoid internal carotid artery aneurysms (odds ratio [OR] 0.440; P = 0.009) had a lower prevalence in LT recipients than in healthy controls. Anterior communicating artery (OR 3.080; P = 0.002) and superior cerebellar artery (OR 8.767; P = 0.017) aneurysms had a higher prevalence in the LT group than in the control. The prevalence of AVM was significantly higher in LT recipients (0.26%) than in healthy controls (0.06%). CONCLUSION: LT recipients showed a different distribution of CA prevalence according to the locations of the cerebral artery and had a higher overall prevalence of AVM than previously healthy controls.
Subject(s)
Cerebrovascular Disorders , Hemorrhagic Stroke , Intracranial Aneurysm , Intracranial Arteriovenous Malformations , Liver Transplantation , Adult , Angiography, Digital Subtraction , Cerebral Angiography , Humans , Intracranial Aneurysm/complications , Intracranial Aneurysm/diagnostic imaging , Intracranial Aneurysm/epidemiology , Prevalence , Retrospective StudiesABSTRACT
BACKGROUND: Growth differentiation factor 15 (GDF15), induced by tissue inflammation and mitochondrial stress, has received significant attention as a biomarker of mitochondrial dysfunction and has been implicated in various age-related diseases. However, the association between circulating GDF15 and sarcopenia-associated outcomes in older adults remains to be established. AIM: To validate previous experimental data and to investigate the possible role of GDF15 in aging and muscle physiology in humans, this study examined serum GDF15 levels in relation to sarcopenia-related parameters in a cohort of older Asian adults. METHODS: Muscle mass and muscle function-related parameters, such as grip strength, gait speed, chair stands, and short physical performance battery score were evaluated by experienced nurses in 125 geriatric participants with or without sarcopenia. Sarcopenia was diagnosed using the Asian-specific cutoff points. Serum GDF15 levels were measured using an enzyme immunoassay kit. RESULTS: Serum GDF15 levels were not significantly different according to sarcopenia status, muscle mass, muscle strength, and physical performance and were not associated with the skeletal muscle index, grip strength, gait speed, time to complete 5 chair stands, and short physical performance battery score, regardless of adjustments for sex, age, and BMI. CONCLUSIONS: These findings indicate that the definite role of GDF15 on muscle metabolism observed in animal models might not be evident in humans and that elevated GDF15 levels might not predict the risk for sarcopenia, at least in older Asian adults.
Subject(s)
Sarcopenia , Aged , Animals , Cross-Sectional Studies , Geriatric Assessment , Growth Differentiation Factor 15 , Hand Strength , Humans , Muscle Strength , Muscle, Skeletal , Sarcopenia/diagnosisABSTRACT
Postoperative ischemic complication results in neurological sequelae and longer hospitalization after unruptured middle cerebral artery (MCA) aneurysm clipping surgery. We evaluated the radiological and patient-related factors associated with ischemic complications after unruptured MCA aneurysm clipping surgery. Patient demographics, radiological findings, and intraoperative factors were compared between patients with and without postoperative ischemic complications. The clinical courses and outcomes of postoperative ischemic complications were compared according to the types of ischemic complication. Forty-two out of 2227 patients (1.9%) developed postoperative ischemic complications after MCA aneurysm clipping. Multivariate analysis revealed that diabetes mellitus (DM) was a patient-related factor. Intraarterial (IA) calcification of the distal internal carotid artery (ICA), preoperative M1 stenosis, and M1 aneurysm were radiological factors that increased the risk of postoperative ischemic complications. DM was significantly associated with divisional branch territory infarction (P = 0.04). The time to first presentation of ischemic complication was significantly longer in divisional branch territory infarction than perforator territory infarction (67.8 ± 75.9 h vs. 22 ± 20.7, P = 0.023). Twelve out of 42 patients with ischemic complications (28.6%) had unfavorable outcome (mRS > 3). Perforator territory infarction was significantly associated with an unfavorable outcome (mRS > 3, P = 0.019). IA calcification of the distal ICA, M1 stenosis and aneurysms, and DM were significantly associated with postoperative ischemic complications after unruptured MCA aneurysm clipping. Patients with DM should be closely monitored postoperatively to detect delayed occurrence of divisional branch infarction. Trial registration number: 2019-1002, Date of registration: January 1, 2005, "retrospectively registered".