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1.
Methods Mol Biol ; 2854: 153-170, 2025.
Article in English | MEDLINE | ID: mdl-39192127

ABSTRACT

cGAS is a key cytosolic dsDNA receptor that senses viral infection and elicits interferon production through the cGAS-cGAMP-STING axis. cGAS is activated by dsDNA from viral and bacterial origins as well as dsDNA leaked from damaged mitochondria and nucleus. Eventually, cGAS activation launches the cell into an antiviral state to restrict the replication of both DNA and RNA viruses. Throughout the long co-evolution, viruses devise many strategies to evade cGAS detection or suppress cGAS activation. We recently reported that the Dengue virus protease NS2B3 proteolytically cleaves human cGAS in its N-terminal region, effectively reducing cGAS binding to DNA and consequent production of the second messenger cGAMP. Several other RNA viruses likely adopt the cleavage strategy. Here, we describe a protocol for the purification of recombinant human cGAS and Dengue NS2B3 protease, as well as the in vitro cleavage assay.


Subject(s)
Dengue Virus , Nucleotidyltransferases , Viral Nonstructural Proteins , Humans , Viral Nonstructural Proteins/metabolism , Nucleotidyltransferases/metabolism , Nucleotidyltransferases/antagonists & inhibitors , Proteolysis , Recombinant Proteins/metabolism , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Nucleotides, Cyclic/metabolism , Dengue/virology , Dengue/metabolism
2.
Luminescence ; 39(10): e4912, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39354830

ABSTRACT

Hence, N,S-CDs with photoluminescent property were simply synthesized via a one-step hydrothermal method. Combined with the commercial reagent Ce4+, a ratiometric fluorescence assay for ascorbic acid (AA) detection was established. Ce4+, possessing oxidization, could directly oxidize o-phenylenediamine (OPD) to form the yellow fluorescent product oxOPD. Under the excitation wavelength of 370 nm, oxOPD had a maximum fluorescence emission at 562 nm. Meanwhile, due to the occurrence of the inner filter effect (IFE), oxOPD quenched the fluorescence of N,S-CDs. However, ascorbic acid (AA) inhibited the oxidation of Ce4+, causing the fluorescence of oxOPD at 562 nm to decrease, accompanied by an increase in the fluorescence belonging to N,S-CDs at 450 nm. Thus, a Ce4+-assisted ratiometric fluorescence method was established for AA detection. The two fluorescence output signals in this method had opposite changing trends, which could reduce system errors and improve the accuracy. This method was successfully applied to the determination of AA in drugs and fruits.


Subject(s)
Ascorbic Acid , Carbon , Quantum Dots , Spectrometry, Fluorescence , Ascorbic Acid/analysis , Ascorbic Acid/chemistry , Carbon/chemistry , Quantum Dots/chemistry , Cerium/chemistry , Fluorescence , Fluorescent Dyes/chemistry , Fluorescent Dyes/chemical synthesis
3.
Environ Monit Assess ; 196(10): 892, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39230774

ABSTRACT

Extreme PM 2.5 pollution has become a significant environmental problem in China in recent years, which is hazardous to human health and daily life. Noticing the importance of investigating the causes of extreme PM 2.5 pollution, this paper classifies cities across China into eight categories (four groups plus two scenarios) based on the generalized extreme value (GEV) distribution using hourly station-level PM 2.5 concentration data, and a series of multi-choice models are employed to assess the probabilities that cities fall into different categories. Various factors such as precursor pollutants and socio-economic factors are considered after controlling for meteorological conditions in each model. It turns out that SO 2 concentration, NO 2 concentration, and population density are the top three factors contributing most to the log ratios. Moreover, in both left- and right-skewed cases, the influence of a one-unit increase of SO 2 concentration on the relative probability of cities falling into different groups shows an increasing trend, while those of NO 2 concentration show a decreasing trend. At the same time, the higher the extreme pollution level, the bigger the effect of SO 2 and NO 2 concentrations on the probability of cities falling into normalized scenarios. The multivariate logit model is used for prediction and policy simulations. In summary, by analyzing the influences of various factors and the heterogeneity of their influence patterns, this paper provides valuable insights in formulating effective emission reduction policies.


Subject(s)
Air Pollutants , Air Pollution , Cities , Environmental Monitoring , Particulate Matter , China , Air Pollution/statistics & numerical data , Air Pollutants/analysis , Particulate Matter/analysis , Sulfur Dioxide/analysis
4.
Mol Ther Oncol ; 32(3): 200855, 2024 Sep 19.
Article in English | MEDLINE | ID: mdl-39262570

ABSTRACT

Myocardin-related transcription factor A (MRTF-A) is a coactivator of serum response factor (SRF), which regulates the expression of genes involved in cell proliferation, migration, and differentiation and has been implicated in hepatocellular carcinoma (HCC) progression. We recently established inhibition of the transcriptional activity of MRTF-A by NS8593 as a novel therapeutic approach for HCC therapy. NS8593 is a negative gating modulator of the transient receptor potential cation channel TRPM7. In this report, we identify an aminobenzimidazole that is highly potent in inhibiting TRPM7 and its interaction with RhoA, leading to decreased SRF transcriptional activity and enhanced nuclear export of MRTF-A, as determined by fluorescence loss in photobleaching (FLIP). This resulted in reduced expression of the MRTF/SRF target genes transforming growth factor ß1 (TGF-ß1) and tetraspanin 5 (TSPAN5), senescence induction, and growth arrest in HCC cells. Replacement of the tetraline core by a 3-aminophenyl substructure yielded inhibitor 10 with higher potency than inhibitor 5, and further structural modifications yielded highly potent inhibitors of SRF activity, 14 and 16. Both compounds were capable of inhibiting cell proliferation and inducing senescence in HCC cells with improved efficacy compared to NS8593. These inhibitors represent valuable tools for understanding the molecular basis of drug development targeting TRPM7 and MRTFs.

5.
Sci Rep ; 14(1): 21030, 2024 09 09.
Article in English | MEDLINE | ID: mdl-39251631

ABSTRACT

Numerous studies have been conducted in other countries on the health effects of exposure to particulate matter with a diameter of 10 microns or less P M 10 , but little research has been conducted in Malaysia, particularly during the haze season. This study intends to investigate how exposure of P M 10 influenced hospital admissions for respiratory diseases during the haze period in peninsula Malaysia and it was further stratified by age group, gender and respiratory diseases categories. The study includes data from all patients with respiratory diseases in 92 government hospitals, as well as P M 10 concentration and meteorological data from 92 monitoring stations in Peninsula Malaysia starting from 1st January 2000 to 31st December 2019. A quasi-poison time series regression with distributed lag nonlinear model (DLNM) was employed in this study to examine the relationship between exposure of P M 10 and hospital admissions for respiratory diseases during the haze period. Haze period for this study has been defined from June to September each year. According to the findings of this study, P M 10 was positively associated with hospitalisation of respiratory disease within 30 lag days under various lag patterns, with lag 25 showing the strongest association (RR = 1.001742, CI 1.001029,1.002456). Using median as a reference, it was discovered that females were more likely than males to be hospitalized for P M 10 exposure. Working age group will be the most affected by the increase in P M 10 exposure with a significant cumulative RR from lag 010 to lag 030. The study found that P M 10 had a significant influence on respiratory hospitalisation in peninsula Malaysia, particularly for lung diseases caused by external agents(CD5). Therefore, it is important to implement effective intervention measures to control P M 10 and reduce the burden of respiratory disease admissions.


Subject(s)
Hospitalization , Particulate Matter , Respiratory Tract Diseases , Humans , Malaysia/epidemiology , Female , Male , Hospitalization/statistics & numerical data , Particulate Matter/analysis , Particulate Matter/adverse effects , Middle Aged , Respiratory Tract Diseases/epidemiology , Respiratory Tract Diseases/etiology , Adult , Aged , Air Pollutants/analysis , Air Pollutants/adverse effects , Air Pollution/adverse effects , Seasons , Adolescent , Young Adult , Child , Child, Preschool
6.
J Biomed Sci ; 31(1): 86, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39232783

ABSTRACT

BACKGROUND: While dengue NS1 antigen has been shown to be associated with disease pathogenesis in some studies, it has not been linked in other studies, with the reasons remaining unclear. NS1 antigen levels in acute dengue are often associated with increased disease severity, but there has been a wide variation in results based on past dengue infection and infecting dengue virus (DENV) serotype. As NS1 engages with many host lipids, we hypothesize that the type of NS1-lipid interactions alters its pathogenicity. METHODS: Primary human monocyte derived macrophages (MDMs) were co-cultured with NS1 alone or with HDL, LDL, LPS and/or platelet activating factor (PAF) from individuals with a history of past dengue fever (DF = 8) or dengue haemorrhagic fever (DHF = 8). IL-1ß levels were measured in culture supernatants, and gene expression analysis carried out in MDMs. Monocyte subpopulations were assessed by flow cytometry. Hierarchical cluster analysis with Euclidean distance calculations were used to differentiate clusters. Differentially expressed variables were extracted and a classifier model was developed to differentiate between past DF and DHF. RESULTS: Significantly higher levels of IL-1ß were seen in culture supernatants when NS1 was co-cultured with LDL (p = 0.01, median = 45.69 pg/ml), but lower levels when NS1 was co-cultured with HDL (p = 0.05, median = 4.617 pg/ml). MDMs of those with past DHF produced higher levels of IL-1ß when NS1 was co-cultured with PAF (p = 0.02). MDMs of individuals with past DHF, were significantly more likely to down-regulate RPLP2 gene expression when macrophages were co-cultured with either PAF alone, or NS1 combined with PAF, or NS1 combined with LDL. When NS1 was co-cultured with PAF, HDL or LDL two clusters were detected based on IL10 expression, but these did not differentiate those with past DF or DHF. CONCLUSIONS: As RPLP2 is important in DENV replication, regulating cellular stress responses and immune responses and IL-10 is associated with severe disease, it would be important to further explore how differential expression of RPLP2 and IL-10 could lead to disease pathogenesis based on NS1 and lipid interactions.


Subject(s)
Dengue Virus , Dengue , Macrophages , Viral Nonstructural Proteins , Humans , Viral Nonstructural Proteins/metabolism , Dengue/virology , Dengue/immunology , Macrophages/metabolism , Male , Adult , Female , Interleukin-1beta/metabolism , Lipids
7.
J Cell Mol Med ; 28(17): e18553, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39239860

ABSTRACT

Microbes are involved in a wide range of biological processes and are closely associated with disease. Inferring potential disease-associated microbes as the biomarkers or drug targets may help prevent, diagnose and treat complex human diseases. However, biological experiments are time-consuming and expensive. In this study, we introduced a new method called iPALM-GLMF, which modelled microbe-disease association prediction as a problem of non-negative matrix factorization with graph dual regularization terms and L 2 , 1 $$ {L}_{2,1} $$ norm regularization terms. The graph dual regularization terms were used to capture potential features in the microbe and disease space, and the L 2 , 1 $$ {L}_{2,1} $$ norm regularization terms were used to ensure the sparsity of the feature matrices obtained from the non-negative matrix factorization and to improve the interpretability. To solve the model, iPALM-GLMF used a non-negative double singular value decomposition to initialize the matrix factorization and adopted an inertial Proximal Alternating Linear Minimization iterative process to obtain the final matrix factorization results. As a result, iPALM-GLMF performed better than other existing methods in leave-one-out cross-validation and fivefold cross-validation. In addition, case studies of different diseases demonstrated that iPALM-GLMF could effectively predict potential microbial-disease associations. iPALM-GLMF is publicly available at https://github.com/LiangzheZhang/iPALM-GLMF.


Subject(s)
Algorithms , Humans , Computational Biology/methods , Microbiota
8.
Drug Test Anal ; 2024 Sep 24.
Article in English | MEDLINE | ID: mdl-39314109

ABSTRACT

Thymosin ß $$ \beta $$ 4 (TB4) is a ubiquitous, highly conserved and abundant peptide among mammals with a critical role in cytoskeleton organization. In spite of its yet non-authorized use as a medicine and being forbidden by the IFHA, the FEI, and the WADA, intelligence and doping control laboratories reported numerous products available online claiming to contain a synthetic acetylated fragment of TB4 or TB4 itself, promoted as a growth factor with regenerative properties. In this article, the first estimation of the endogenous TB4 concentration in racing horses' blood samples was performed through a population study. We reveal that this concentration does not significantly depend on gender, age, nor horse breed. We highlight that the TB4 concentration increases significantly and rapidly in plasma stored at 4°C when not separated from blood cells due to cell lysis. Finally, we also demonstrate that the detection of a non-natural synthesis impurity is possible in equine plasma after a single dose administration of a TB4 containing product to a horse.

9.
PeerJ Comput Sci ; 10: e2259, 2024.
Article in English | MEDLINE | ID: mdl-39314695

ABSTRACT

Routing in vehicular ad hoc networks (VANETs) enables vehicles to communicate for safety and non-safety applications. However, there are limitations in wireless communication that can degrade VANET performance, so it is crucial to optimize the operation of routing protocols to address this. Various routing protocols employed the expected transmission count (ETX) in their operation as one way to achieve the required efficiency and robustness. ETX is used to estimate link quality for improved route selection. While some studies have evaluated the utilization of ETX in specific protocols, they lack a comprehensive analysis across protocols under varied network conditions. This research provides a comprehensive comparative evaluation of ETX-based routing protocols for VANETs using the nomadic community mobility model. It covers a foundational routing protocol, ad hoc on-demand distance vector (AODV), as well as newer variants that utilize ETX, lightweight ETX (LETX), and power-based light reverse ETX (PLR-ETX), which are referred to herein as AODV-ETX, AODV-LETX, and AODV-PLR, respectively. The protocols are thoroughly analyzed via ns-3 simulations under different traffic and mobility scenarios. Our evaluation model considers five performance parameters including throughput, routing overhead, end-to-end delay, packet loss, and underutilization ratio. The analysis provides insight into designing robust and adaptive ETX routing for VANET to better serve emerging intelligent transportation system applications through a better understanding of protocol performance under different network conditions. The key findings show that ETX-optimized routing can provide significant performance enhancements in terms of end-to-end delay, throughput, routing overhead, packet loss and underutilization ratio. The extensive simulations demonstrated that AODV-PLR outperforms its counterparts AODV-ETX and AODV-LETX and the foundational AODV routing protocol across the performance metrics.

10.
Sci Rep ; 14(1): 21949, 2024 Sep 20.
Article in English | MEDLINE | ID: mdl-39304693

ABSTRACT

The captivating realm of the nonlinear coupled Davey-Stewartson Fokas system is explored in this research paper. As a powerful tool, the proposed system is utilized for the realistic representation of various non-linear dynamical mechanisms in different fields of sciences and engineering including non-linear optical fibers, plasma physics and water waves theory. Two distinct exact methods, namely the modified auxiliary equation method and the extended ( G ' / G 2 ) -expansion method, are utilized to acquire the exact soliton solutions of the non-linear coupled Davey-Stewartson Fokas system. A plethora of novel soliton solutions containing anti-kink, kink, bright, dark, dark-bright, bright-dark and some other singular soliton solutions, have been obtained using the employed exact methods. The significance of proposed manuscript lies in the novelty of obtained solutions. Kink, dark and bright solitons have wide applications in optical fiber communications, plasma physics and water waves dynamics. The acquired nontrivial exact solutions contain exponential, trigonometric, rational and hyperbolic functions. Some obtained solutions are visually represented through graphical simulations of 3D, 2D-contour and 2D-line plots, providing a comprehensive visualization of the soliton dynamics.The modulation instability of the proposed nonlinear system has been investigated, which ensures the stability of the system.

11.
BMC Genomics ; 25(1): 885, 2024 Sep 20.
Article in English | MEDLINE | ID: mdl-39304826

ABSTRACT

MicroRNAs (miRNAs) have been demonstrated to be closely related to human diseases. Studying the potential associations between miRNAs and diseases contributes to our understanding of disease pathogenic mechanisms. As traditional biological experiments are costly and time-consuming, computational models can be considered as effective complementary tools. In this study, we propose a novel model of robust orthogonal non-negative matrix tri-factorization (NMTF) with self-paced learning and dual hypergraph regularization, named SPLHRNMTF, to predict miRNA-disease associations. More specifically, SPLHRNMTF first uses a non-linear fusion method to obtain miRNA and disease comprehensive similarity. Subsequently, the improved miRNA-disease association matrix is reformulated based on weighted k-nearest neighbor profiles to correct false-negative associations. In addition, we utilize L 2 , 1 norm to replace Frobenius norm to calculate residual error, alleviating the impact of noise and outliers on prediction performance. Then, we integrate self-paced learning into NMTF to alleviate the model from falling into bad local optimal solutions by gradually including samples from easy to complex. Finally, hypergraph regularization is introduced to capture high-order complex relations from hypergraphs related to miRNAs and diseases. In 5-fold cross-validation five times experiments, SPLHRNMTF obtains higher average AUC values than other baseline models. Moreover, the case studies on breast neoplasms and lung neoplasms further demonstrate the accuracy of SPLHRNMTF. Meanwhile, the potential associations discovered are of biological significance.


Subject(s)
Computational Biology , MicroRNAs , MicroRNAs/genetics , Humans , Computational Biology/methods , Algorithms , Genetic Predisposition to Disease , Machine Learning , Lung Neoplasms/genetics
12.
Eur J Appl Physiol ; 2024 Sep 23.
Article in English | MEDLINE | ID: mdl-39312007

ABSTRACT

PURPOSE: The biochemical background of the (near-)linear direct relationship between the curvature constant (W') of the power-duration curve and the magnitude ( Δ V ˙ O 2sc ) of the slow component of the V ˙ O 2 on-kinetics ( V ˙ O 2sc ) as well as reverse relationship between critical power (CP) and the characteristic transition time (t0.63, analogous to τp) of the primary phase II of the V ˙ O 2 on-kinetics encountered in experimental studies is studied. METHODS: A computer model of the bioenergetic system in skeletal muscle, involving the each-step-activation mechanism of work transitions and Pi double-threshold mechanism of muscle fatigue, is used. RESULTS: The activity (rate constant) (kadd) of the additional ATP usage, underlying the slow component, determines to a large extent the (near-)linear direct W'- Δ V ˙ O 2sc relationship, as an increase in kadd increases markedly both W' and Δ V ˙ O 2sc . t0.63 is a derivative of the changes in metabolite (M = PCr or Cr or Pi) concentrations between rest and the steady-state of the phase II M on-kinetics after the onset of exercise. The oxidative phosphorylation (OXPHOS) activity (kOX) mostly determines the (near)-linear inverse CP-t0.63 relationship, as an increase in kOX markedly decreases ΔM and t0.63, and elevates CP. CONCLUSIONS: The V ˙ O 2 on-kinetics (e.g., V ˙ O 2sc or t0.63) cannot cause anything in the system, as it is an emergent property of the system functioning on the biochemical level. Physiological variables: muscle V ˙ O 2sc and W' as well as t0.63 and CP, and relationships between them, are determined by biochemical parameters, mainly kadd and kOX, respectively.

13.
MethodsX ; 13: 102944, 2024 Dec.
Article in English | MEDLINE | ID: mdl-39315399

ABSTRACT

This study optimized a gas chromatography-tandem triple quadrupole mass spectrometry (GC-MS/MS) method for the determination of 21 persistent organic pollutants (POPs) in Irtysh River water, including 14 organochlorines (OCPs) and 7 polychlorinated biphenyls (PCBs). Factors such as column temperature ramping, selection of qualitative and quantitative ion pairs and collision energy were considered to achieve perfect separation and accurate quantification of all 21 target compounds. The limits of detection (LOD) for PCBs and OCPs ranged from 0.21 to 1.18 ng/L. Applying this method to detect POPs in the Irtysh River revealed concentrations of OCPs ranging from ND to 20.2 ng/L and PCBs from ND to 0.411 ng/L. Source analysis indicated that POPs in the Irtysh River mainly originate from historical industrial and agricultural activities, particularly the deliberate use of pesticides. To ensure ecological safety and human health, expanding the range of target analytes and monitoring periods is necessary. This study provides:•Qualitative and quantitative analysis methods for 7 PCBs and 14 OCPs.•Recoveries achieved ranged between 74.6 to 109 % with RSD less than 15 %.•Analysis of sources, transport pathways, accumulation status, and ecological risks of PCBs and OCPs in the Irtysh River.

14.
J Physiol ; 2024 Sep 24.
Article in English | MEDLINE | ID: mdl-39316014

ABSTRACT

It remains unclear whether feedback from group III/IV muscle afferents is of continuous significance for regulating the pulmonary response during prolonged (>5 min), steady-state exercise. To elucidate the influence of these sensory neurons on hyperpnoea, gas exchange efficiency, arterial oxygenation and acid-base balance during prolonged locomotor exercise, 13 healthy participants (4 females; 21 (3) years, V ̇ O 2 max ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{max}}}}$ : 46 (8) ml/kg/min) performed consecutive constant-load cycling bouts at ∼50% (20 min), ∼75% (20 min) and ∼100% (5 min) of V ̇ O 2 max ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{max}}}}$ with intact (CTRL) and pharmacologically attenuated (lumbar intrathecal fentanyl; FENT) group III/IV muscle afferent feedback from the legs. Pulmonary responses were continuously recorded and arterial blood (radial catheter) periodically collected throughout the exercise. Pulmonary gas exchange efficiency was evaluated using the alveolar-arterial P O 2 ${{P}_{{{{\mathrm{O}}}_{\mathrm{2}}}}}$ difference ( A - a D O 2 ${\mathrm{A - a}}{{D}_{{{{\mathrm{O}}}_{\mathrm{2}}}}}$ ). There were no differences in any of the variables of interest between conditions before the start of the exercise. Pulmonary ventilation was up to 20% lower across all intensities during FENT compared to CTRL exercise (P < 0.001) and this hypoventilation was accompanied by an up to 10% lower arterial P O 2 ${{P}_{{{{\mathrm{O}}}_{\mathrm{2}}}}}$ and a 2-4 mmHg higher P C O 2 ${{P}_{{\mathrm{C}}{{{\mathrm{O}}}_{\mathrm{2}}}}}$ (both P < 0.001). The exercise-induced widening of A - a D O 2 ${\mathrm{A - a}}{{D}_{{{{\mathrm{O}}}_{\mathrm{2}}}}}$ was up to 25% larger during FENT compared to CTRL (P < 0.001). Importantly, the differences developed within the first minute of each stage and persisted, or further increased, throughout the remainder of each bout. These findings reflect a critical and time-independent significance of feedback from group III/IV leg muscle afferents for continuously regulating the ventilatory response, gas exchange efficiency, arterial oxygenation and acid-base balance during human locomotion. KEY POINTS: Feedback from group III/IV leg muscle afferents reflexly contributes to hyperpnoea during short duration (i.e. <5 min) locomotor exercise. Whether continuous feedback from these sensory neurons is obligatory to ensure adequate pulmonary responses during steady-state exercise of longer duration remains unknown. Lumbar intrathecal fentanyl was used to attenuate the central projection of group III/IV leg muscle afferents during prolonged locomotor exercise (i.e. 45 min) at intensities ranging from 50% to 100% of V ̇ O 2 max ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{max}}}}$ . Without affecting the metabolic rate, afferent blockade compromised pulmonary ventilation and gas exchange efficiency, consistently impairing arterial oxygenation and facilitating respiratory acidosis throughout exercise. These findings reflect the time-independent significance of feedback from group III/IV muscle afferents for regulating exercise hyperpnoea and gas exchange efficiency, and thus for optimizing arterial oxygenation and acid-base balance, during prolonged human locomotion.

15.
Poult Sci ; 103(12): 104322, 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39316982

ABSTRACT

Duck Tembusu virus (DTMUV) of the Orthoflavivirus genus poses a significant threat to waterfowl aquaculture. Nonstructural protein 1 (NS1), a multifunctional glycoprotein, exists in various oligomeric forms and performs diverse functions. The greasy finger (GF) region within NS1 of other flaviviruses has been shown to be a crucial component of the hydrophobic protrusion aiding in anchoring NS1 to the endoplasmic reticulum (ER). However, detailed studies on the role of the GF region in viral proliferation in vitro and the biological properties of NS1 remain scarce. A series of recombinant DTMUV (rDTMUV) with mutations in the GF region, including NS1-F158A, G159A, F160A, G161A, V162A, L163A, F160R, multipoint mutations (GF-4M), or regional deletions (ΔGF), were rescued using a DNA-based reverse genetics system. Only 5 rDTMUV variants (G159A, F160A, G161A, V162A, and L163A) could be rescued successfully, and these mutations were found to impair replication, reduce virulence, and decrease plaque size, as shown by growth kinetics, duck embryo virulence, and plaque assays, respectively. Upon examining NS1 expression by western blot, we discovered that secreted NS1 (sNS1) presented in large quantities in the supernatant of cells infected with rDTMUV-NS1-G159A, whereas intracellular NS1 was less abundant. These mutations also impacted the primary forms and secretion rates of NS1 in cases of overexpression by western blot and indirect ELISA. Exception for F160A and G161A, which showed decreased secretion rates, all other mutations increased sNS1 expression, with the most pronounced increase observed in F158A and ΔGF, and rDTMUV with these mutations can't be rescued. Co-localization studies of NS1 with the ER demonstrated that the ΔGF mutation attenuated NS1 anchoring to the ER, thereby inhibiting its intracellular residence and promoting secretion. Although these effects vary between flaviviruses, our data reveal that the GF region of NS1 is crucial for viral proliferation and NS1 secretion.

16.
Sci Rep ; 14(1): 21897, 2024 09 19.
Article in English | MEDLINE | ID: mdl-39300232

ABSTRACT

Psoriasis is a chronic, non-contagious, immune-mediated skin disorder. Inflammation of the skin's surface is characterised by scaly white, red, or silvery spots that occur due to the hyper-proliferation of keratinocytes in the epidermal layer. Primarily, pharmaceutical drugs or immune therapy are used to treat psoriasis. We are all aware that, certain therapeutic strategies can have some adverse effects, and over time, that hidden inflammation may manifest. This article introduces a mathematical model for psoriasis, formulated by employing a set of nonlinear ordinary differential equations (ODEs) that describe the densities of T-cells, dendritic cells (DCs), keratinocytes, and mesenchymal stromal cells (MSCs) as basic cell populations. A tumor necrosis factor- α ( T N F - α ) inhibitor has been imposed from the initial stage of the treatment regime, using the optimal control theoretic approach, and the numerical results have been observed. After 80 days of monitoring using only biologic T N F - α inhibitors, if this approach did not provide the intended outcomes (when severity arises), stem cells are administered a few times in a pulsed manner as a cell replacement technique in addition to this anti T N F - α medicine. We have observed the combined therapeutic benefit of stem cell replacement with a T N F - α inhibitor from a mathematical point of view. The theoretical analysis and the numerical results revealed that stem cell transplantation, along with a T N F - α inhibitor, is a promising psoriasis treatment option moving forward.


Subject(s)
Mesenchymal Stem Cell Transplantation , Psoriasis , Psoriasis/therapy , Psoriasis/drug therapy , Humans , Mesenchymal Stem Cell Transplantation/methods , Mesenchymal Stem Cells , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Models, Theoretical , Keratinocytes/drug effects , T-Lymphocytes/immunology , T-Lymphocytes/drug effects , Dendritic Cells/immunology
17.
Molecules ; 29(17)2024 Aug 27.
Article in English | MEDLINE | ID: mdl-39274895

ABSTRACT

Orthoflaviviruses, including zika (ZIKV), West Nile (WNV), and dengue (DENV) virus, induce severely debilitating infections and contribute significantly to the global disease burden, yet no clinically approved antiviral treatments exist. This review offers a comprehensive analysis of small-molecule drug development targeting orthoflaviviral infections, with a focus on NS2B-NS3 inhibition. We systematically examined clinical trials, preclinical efficacy studies, and modes of action for various viral replication inhibitors, emphasizing allosteric and orthosteric drugs inhibiting NS2B-NS3 protease with in vivo efficacy and in vitro-tested competitive NS2B-NS3 inhibitors with cellular efficacy. Our findings revealed that several compounds with in vivo preclinical efficacy failed to show clinical antiviral efficacy. NS3-NS4B inhibitors, such as JNJ-64281802 and EYU688, show promise, recently entering clinical trials, underscoring the importance of developing novel viral replication inhibitors targeting viral machinery. To date, the only NS2B-NS3 inhibitor that has undergone clinical trials is doxycycline, however, its mechanism of action and clinical efficacy as viral growth inhibitor require additional investigation. SYC-1307, an allosteric inhibitor, exhibits high in vivo efficacy, while temoporfin and methylene blue represent promising orthosteric non-competitive inhibitors. Compound 71, a competitive NS2B-NS3 inhibitor, emerges as a leading preclinical candidate due to its high cellular antiviral efficacy, minimal cytotoxicity, and favorable in vitro pharmacokinetic parameters. Challenges remain in developing competitive NS2B-NS3 inhibitors, including appropriate biochemical inhibition assays as well as the selectivity and conformational flexibility of the protease, complicating effective antiviral treatment design.


Subject(s)
Antiviral Agents , Viral Nonstructural Proteins , Antiviral Agents/pharmacology , Antiviral Agents/chemistry , Humans , Viral Nonstructural Proteins/antagonists & inhibitors , Viral Nonstructural Proteins/metabolism , Animals , Protease Inhibitors/pharmacology , Protease Inhibitors/chemistry , Protease Inhibitors/therapeutic use , Clinical Trials as Topic , Serine Endopeptidases/metabolism , Virus Replication/drug effects , Dengue Virus/drug effects , Zika Virus/drug effects , West Nile virus/drug effects
18.
Protein Sci ; 33(10): e5121, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39276019

ABSTRACT

Bispecific antibodies (BsAbs) have emerged as a major class of antibody therapeutics owing to their substantial potential in disease treatment. While several BsAbs have been successfully approved in recent years, ongoing development efforts continue to focus on optimizing various BsAbs tailored to particular antigens and action mechanisms, aiming to achieve favorable physicochemical properties. BsAbs generally encounter challenges due to their unfavorable physicochemical characteristics and poor manufacturing efficiencies, highlighting the need for optimization to achieve reliable productivity and developability. Herein, we describe the development of a novel symmetric BsAb, REGULGENT™ (N-term/C-term), comprising two Fab domains, using a common light chain. The heavy chain fragment encoded two antigen-binding determinants in one chain. The design and production of REGULGENT™ (N-term/C-term) are simple owing to the use of the same light chain, which does not induce heavy and light chain mispairing, frequently observed with the asymmetric BsAb format. REGULGENT™ (N-term/C-term) exhibited high expression and low aggregation characteristics during cell culture and stress treatment under low pH conditions. Differential scanning calorimetric data indicated that REGULGENT™ molecules had high conformational stability, similar to that of stabilized monoclonal antibodies. Surface plasmon resonance data showed that REGULGENT™ (N-term/C-term) could bind to two antigens simultaneously and exhibited a high affinity for two antigens. In summary, the symmetric BsAb format of REGULGENT™ confers its desirable IgG-like physicochemical properties, thus making it an excellent candidate for commercial development. The findings demonstrate a novel BsAb with substantial development potential for clinical applications.


Subject(s)
Antibodies, Bispecific , Protein Engineering , Antibodies, Bispecific/chemistry , Antibodies, Bispecific/immunology , Antibodies, Bispecific/genetics , Humans , Protein Engineering/methods , Protein Stability , Immunoglobulin Light Chains/chemistry , Immunoglobulin Light Chains/genetics , Immunoglobulin Light Chains/metabolism , Animals
19.
Lett Math Phys ; 114(5): 111, 2024.
Article in English | MEDLINE | ID: mdl-39280076

ABSTRACT

The amplituhedron is a mathematical object which was introduced to provide a geometric origin of scattering amplitudes in N = 4 super Yang-Mills theory. It generalizes cyclic polytopes and the positive Grassmannian and has a very rich combinatorics with connections to cluster algebras. In this article, we provide a series of results about tiles and tilings of the m = 4 amplituhedron. Firstly, we provide a full characterization of facets of BCFW tiles in terms of cluster variables for Gr 4 , n . Secondly, we exhibit a tiling of the m = 4 amplituhedron which involves a tile which does not come from the BCFW recurrence-the spurion tile, which also satisfies all cluster properties. Finally, strengthening the connection with cluster algebras, we show that each standard BCFW tile is the positive part of a cluster variety, which allows us to compute the canonical form of each such tile explicitly in terms of cluster variables for Gr 4 , n . This paper is a companion to our previous paper "Cluster algebras and tilings for the m = 4 amplituhedron."

20.
J Mol Model ; 30(10): 340, 2024 Sep 18.
Article in English | MEDLINE | ID: mdl-39289190

ABSTRACT

CONTEXT: The diatomic molecules of potassium 39 K 2 a 3 ∑ u + is widely used in industrial chemicals and alternative energy. Besides that, 39 K 2 a 3 ∑ u + is very useful for researching molecular interactions and energy states, especially in the context of quantum chemistry and spectroscopy. In the present work, a newly proposed diatomic potential model within relativistic and non-relativistic quantum mechanics has been considered, to obtain corresponding energy eigenvalues and related normalized eigenfunctions. METHODS: The Dirac equation has been solved for an arbitrary spin-orbit quantum number κ using the path integral technique with the q -deformed generalized Pöschl-Teller potential ( D G P T ) . By including a Pekeris-type approximation to handle the centrifugal factor, it was possible to obtain the spin and pseudospin-symmetric solution of the relativistic energy eigenvalues and wave equation. To assess the correctness of this work, Maple software was used to present some numerical findings for various values of n and κ . With the constraint λ ~ > η ~ + 1 , it was shown that in the situation of pseudospin symmetry, only bound states exist with negative energy. In the non-relativistic limits, the non-relativistic ro-vibrational energy expression of the diatomic molecule is derived from the relativistic energy equation under spin symmetry. Under Varshni conditions, both vibrational and ro-vibrational energies of the 39 K 2 a 3 ∑ u + molecule were computed and compared with the RKR data. The average absolute percentage deviations from the RKR data obtained for the potassium molecule are 0.5018 % . This demonstrates that the ( D G P T ) model is a very consistent model to study and characterize diatomic molecules.

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