NS1 Protein Research Articles

Exploration and Validation of Lead Molecules against Yellow Fever through High Throughput Virtual Screening and Molecular Dynamics Simulation

Background: Yellow fever (YF) is a mosquito-borne flaviviral hemorrhagic fever (VHF) that causes severe hepatitis, renal failure, bleeding, and quick terminal events such as shock and multi-organ failure. There are currently no particular anti-viral medications for the management of the YF virus (YFV). Despite the availability of a commercial YFV vaccination, there are roughly 30,000 fatalities globally each year, with instances rising over the previous 20 years. After being translocated into the endoplasmic reticulum lumen, glycosylated NS1 resides as a membrane-associated dimer, where it is required for viral genome replication. The secreted hexamer NS1 has a role in immune evasion and pathogenesis and has been discovered as a possible diagnostic marker for the early identification of viral infections. Objective: The main aim of this study is to analyze the small molecule as a potent drug candidate against the target NS1 protein. Methods: In this study, Computational approaches, including high throughput virtual screening, molecular docking, and dynamics simulation, were carried out against the target NS1 protein using three different chemical libraries Enamine, Asinex, and NCI. The selected lead compounds were validated through HOMO-LUMO analysis, ADME prediction, and Toxicity parameters to analyze the biological and pharmacological properties of the lead small molecules. Results: From the result, it was concluded that the leads possessed the highest docking scores, interacting with the binding residues, and were stable in the simulation period. Conclusion: Overall findings revealed that the lead three small molecules could act as the potential drug candidate for the target NS1 protein to inhibit the diseasing efficacy of Yellow fever.

Development of immunochromatographic strip assay to detect recent infection of Japanese encephalitis virus in swine population

Japanese Encephalitis (JE) is a mosquito borne re-emerging viral zoonotic disease. Sero-conversion in swine occurs 2–3 weeks before human infection, thus swine act as a suitable sentinel for predicting JE outbreaks in humans. The present study was undertaken with the objective of developing immunochromatographic strip (ICS) assay to detect recent infection of Japanese Encephalitis virus (JEV) in swine population. The two formats of ICS assay were standardized. In the first format, gold nanoparticles (GNP) were conjugated with goat anti-pig IgM (50 μg/ml) followed by spotting of recombinant NS1 protein (1 mg/ml) of JEV on NCM as test line and protein G (1 mg/ml) as control line. In the format-II, GNP were conjugated with rNS1 protein (50 μg/ml) followed by spotting of Goat anti-pig IgM (1 mg/ml) as test line and IgG against rNS1 (1 mg/ml) as control line. To decrease the non- specific binding, blocking of serum and nitrocellulose membrane (NCM) was done using 5% SMP in PBS-T and 1% BSA, respectively. Best reaction conditions for the assay were observed when 10 μl of GNP conjugate and 50 μl of 1:10 SMP blocked sera was reacted on BSA blocked NCM followed by reaction time of 15 mins. Samples showing both test and control line were considered positive whereas samples showing only control line were considered negative. A total of 318 field swine sera samples were screened using indirect IgM ELISA and developed ICS assay. Relative diagnostic sensitivity and specificity of format-I was 81.25% and 93.0% whereas of format-II was 87.50% and 62.93%, respectively. Out of 318 samples tested, 32 were positive through IgM ELISA with sero-positivity of 10.06% while sero-positivity with format-I of ICS was 8.1%. Owing to optimal sensitivity and higher specificity of format-I, it was validated in three different labs and the kappa agreement ranged from 0.80 to 1, which signifies excellent repeatability of the developed assay to test field swine sera samples for detecting recent JEV infection.

Characterization of Circulating HCV Genotypes: A Cohort Study in Uttar Pradesh, India

Hepatitis C virus infection is one of the main causes of liver disease that can lead to liver cirrhosis and finally to the chronic development of Hepatocellular Carcinoma (HCC). With 8 different HCV genotypes circulating, it becomes necessary to characterize the pathogenesis caused by each one of the HCV genotypes infecting population of a particular setting. Present study aims to identify the circulating Hepatitis C virus (HCV) genotypes in the different areas of State of Uttar Pradesh, India and understand their clinical etiology and related co-morbidities. The patients reporting to Sharda Hospital, Uttar Pradesh, India who were diagnosed positive for HCV were included in the study. The informed consent was obtained and then blood was drawn. In-house primers, for all the 8 genotypes were prepared and RT-PCR was performed. The amplified product was subjected to Agarose gel electrophoresis to identify the genotypes present in individual samples. Total 30 serum samples were taken. Of these, 21 (70%) showed presence of multiple genotypes, while 7 (23.33%) showed positivity for single genotype and two did not show any bands. Presence of multiple genotypes in individual patient has been reported for the first time. The pathological consequences of multiple genotypes within one host need to be studied further in terms of increased risk of developing a chronic liver disease. Further studies are being undertaken to study association of specific HCV genotype and multiple genotypes, Core, NS3 and NS5 viral proteins with the disease progression to develop predictors of liver cirrhosis and HCC.

Molecular screening of phytocompounds targeting the interface between influenza A NS1 and TRIM25 to enhance host immune responses

BackgroundInfluenza A virus causes severe respiratory illnesses, especially in developing nations where most child deaths under 5 occur due to lower respiratory tract infections. The RIG-I protein acts as a sensor for viral dsRNA, triggering interferon production through K63-linked poly-ubiquitin chains synthesized by TRIM25. However, the influenza A virus's NS1 protein hinders this process by binding to TRIM25, disrupting its association with RIG-I and preventing downstream interferon signalling, contributing to the virus's evasion of the immune response. MethodsIn our study we used structural-based drug designing, molecular simulation, and binding free energy approaches to identify the potent phytocompounds from various natural product databases (>100,000 compounds) able to inhibit the binding of NS1 with the TRIM25. ResultsThe molecular screening identified EA-8411902 and EA-19951545 from East African Natural Products Database, NA-390261 and NA-71 from North African Natural Products Database, SA-65230 and SA- 4477104 from South African Natural Compounds Database, NEA- 361 and NEA- 4524784 from North-East African Natural Products Database, TCM-4444713 and TCM-6056 from Traditional Chinese Medicines Database as top hits. The molecular docking and binding free energies results revealed that these compounds have high affinity with the specific active site residues (Leu95, Ser99, and Tyr89) involved in the interaction with TRIM25. Additionally, analysis of structural dynamics, binding free energy, and dissociation constants demonstrates a notably stronger binding affinity of these compounds with the NS1 protein. Moreover, all selected compounds exhibit exceptional ADMET properties, including high water solubility, gastrointestinal absorption, and an absence of hepatotoxicity, while adhering to Lipinski’s rule. ConclusionOur molecular simulation findings highlight that the identified compounds demonstrate high affinity for specific active site residues involved in the NS1-TRIM25 interaction, exhibit exceptional ADMET properties, and adhere to drug-likeness criteria, thus presenting promising candidates for further development as antiviral agents against influenza A virus infections.

Comprehensive analysis of early T cell responses to acute Zika Virus infection during the first epidemic in Bahia, Brazil

Background In most cases, Zika virus (ZIKV) causes a self-limited acute illness in adults, characterized by mild clinical symptoms that resolve within a few days. Immune responses, both innate and adaptive, play a central role in controlling and eliminating virus-infected cells during the early stages of infection. Aim To test the hypothesis that circulating T cells exhibit phenotypic and functional activation characteristics during the viremic phase of ZIKV infection. Methods A comprehensive analysis using mass cytometry was performed on peripheral blood mononuclear cells obtained from patients with acute ZIKV infection (as confirmed by RT-PCR) and compared with that from healthy donors (HD). The frequency of IFN-γ-producing T cells in response to peptide pools covering immunogenic regions of structural and nonstructural ZIKV proteins was quantified using an ELISpot assay. Results Circulating CD4+ and CD8+ T lymphocytes from ZIKV-infected patients expressed higher levels of IFN-γ and pSTAT-5, as well as cell surface markers associated with proliferation (Ki-67), activation ((HLA-DR, CD38) or exhaustion (PD1 and CTLA-4), compared to those from HD. Activation of CD4+ and CD8+ memory T cell subsets, including Transitional Memory T Cells (TTM), Effector Memory T cells (TEM), and Effector Memory T cells Re-expressing CD45RA (TEMRA), was prominent among CD4+ T cell subset of ZIKV-infected patients and was associated with increased levels of IFN-γ, pSTAT-5, Ki-67, CTLA-4, and PD1, as compared to HD. Additionally, approximately 30% of ZIKV-infected patients exhibited a T cell response primarily directed against the ZIKV NS5 protein. Conclusion Circulating T lymphocytes spontaneously produce IFN-γ and express elevated levels of pSTAT-5 during the early phase of ZIKV infection whereas recognition of ZIKV antigen results in the generation of virus-specific IFN-γ-producing T cells.

The interaction of GRP78 and Zika virus E and NS1 proteins occurs in a chaperone-client manner

Glucose regulated protein 78 (GRP78) is a chaperone protein that is a central mediator of the unfolded protein response, a key cellular stress response pathway. GRP78 has been shown to be critically required for infection and replication of a number of flaviviruses, and to interact with both non-structural (NS) and structural flavivirus proteins. However, the nature of the specific interaction between GRP78 and viral proteins remains largely unknown. This study aimed to characterize the binding domain and critical amino acid residues that mediate the interaction of GRP78 to ZIKV E and NS1 proteins. Recombinant EGFP fused GRP78 and individual subdomains (the nucleotide binding domain (NBD) and the substrate binding domain (SBD)) were used as a bait protein and co-expressed with full length or truncated ZIKV E and NS1 proteins in HEK293T/17 cells. Protein–protein interactions were determined by a co-immunoprecipitation assay. From the results, both the NBD and the SBD of GRP78 were crucial for an effective interaction. Single amino acid substitutions in the SBD showed that R492E and T518A mutants significantly reduced the binding affinity of GRP78 to ZIKV E and NS1 proteins. Notably, the interaction of GRP78 with ZIKV E was stably maintained against various single amino acid substitutions on ZIKV E domain III and with all truncated ZIKV E and NS1 proteins. Collectively, the results suggest that the principal binding between GRP78 and viral proteins is mainly a classic canonical chaperone protein-client interaction. The blocking of GRP78 chaperone function effectively inhibited ZIKV infection and replication in neuronal progenitor cells. Our findings reveal that GRP78 is a potential host target for anti-ZIKV therapeutics.

Structural and functional insights in flavivirus NS5 proteins gained by the structure of Ntaya virus polymerase and methyltransferase

Flaviviruses are single-stranded positive-sense RNA (+RNA) viruses that are responsible for several (re)emerging diseases such as yellow, dengue, or West Nile fevers. The Zika epidemic highlighted their dangerousness when a relatively benign virus known since the 1950s turned into a deadly pathogen. The central protein for their replication is NS5 (non-structural protein 5), which is composed of the N-terminal methyltransferase (MTase) domain and the C-terminal RNA-dependent RNA-polymerase (RdRp) domain. It is responsible for both RNA replication and installation of the 5' RNA cap. We structurally and biochemically analyzed the Ntaya virus MTase and RdRp domains and we compared their properties to other flaviviral NS5s. The enzymatic centers are well conserved across Flaviviridae, suggesting that the development of drugs targeting all flaviviruses is feasible. However, the enzymatic activities of the isolated proteins were significantly different for the MTase domains.

Determination and Characterization of Novel Papillomavirus and Parvovirus Associated with Mass Mortality of Chinese Tongue Sole (Cynoglossus semilaevis) in China.

A massive mortality event concerning farmed Chinese tongue soles occurred in Tianjin, China, and the causative agent remains unknown. Here, a novel Cynoglossus semilaevis papillomavirus (CsPaV) and parvovirus (CsPV) were simultaneously isolated and identified from diseased fish via electron microscopy, virus isolation, genome sequencing, experimental challenges, and fluorescence in situ hybridization (FISH). Electron microscopy showed large numbers of virus particles present in the tissues of diseased fish. Viruses that were isolated and propagated in flounder gill cells (FG) induced typical cytopathic effects (CPE). The cumulative mortality of fish given intraperitoneal injections reached 100% at 7 dpi. The complete genomes of CsPaV and CsPV comprised 5939 bp and 3663 bp, respectively, and the genomes shared no nucleotide sequence similarities with other viruses. Phylogenetic analysis based on the L1 and NS1 protein sequences revealed that CsPaV and CsPV were novel members of the Papillomaviridae and Parvoviridae families. The FISH results showed positive signals in the spleen tissues of infected fish, and both viruses could co-infect single cells. This study represents the first report where novel papillomavirus and parvovirus are identified in farmed marine cultured fish, and it provides a basis for further studies on the prevention and treatment of emerging viral diseases.

First National Prevalence in Italian Horse Population and Phylogenesis Highlight a Fourth Sub-Type Candidate of Equine Hepacivirus.

Equine hepacivirus (EqHV, Flaviviridae, hepacivirus) is a small, enveloped RNA virus generally causing sub-clinical hepatitis with occasional fatalities. EqHV is reported in equids worldwide, but for Italy data are limited. To address this, a survey study was set up to estimate prevalence at a national level and among different production categories (equestrian; competition; work and meat; reproduction) and national macro-regions (North, Central, South, and Islands). Data obtained testing 1801 horse serum samples by Real-Time RT PCR were compared within the categories and regions. The NS3 fragment of the PCR-positive samples was sequenced by Sanger protocol for phylogenetic and mutational analysis. The tertiary structure of the NS3 protein was also assessed. The estimated national prevalence was 4.27% [1.97-6.59, 95% CI] and no statistical differences were detected among production categories and macro-regions. The phylogenesis confirmed the distribution in Italy of the three known EqHV subtypes, also suggesting a possible fourth sub-type that, however, requires further confirmation. Mutational profiles that could also affect the NS3 binding affinity to the viral RNA were detected. The present paper demonstrates that EqHV should be included in diagnostic protocols when investigating causes of hepatitis, and in quality control protocols for blood derived products due to its parental transmission.

Novel mutation N588 residue in the NS1 protein of feline parvovirus greatly augments viral replication.

Feline parvovirus (FPV) infection is highly fatal in felines. NS1, which is a key nonstructural protein of FPV, can inhibit host innate immunity and promote viral replication, which is the main reason for the severe pathogenicity of FPV. However, the mechanism by which the NS1 protein disrupts host immunity and regulates viral replication is still unclear. Here, we identified an FPV M1 strain that is regulated by the NS1 protein and has more pronounced suppression of innate immunity, resulting in robust replication. We found that the neutralization titer of the FPV M1 strain was significantly lower than that of the other strains. Moreover, FPV M1 had powerful replication ability, and the FPV M1-NS1 protein had heightened efficacy in repressing interferon-stimulated genes (ISGs) expression. Subsequently, we constructed an FPV reverse genetic system, which confirmed that the N588 residue of FPV M1-NS1 protein is a key amino acid that bolsters viral proliferation. Recombinant virus containing N588 also had stronger ability to inhibit ISGs, and lower ISGs levels promoted viral replication and reduced the neutralization titer of the positive control serum. Finally, we confirmed that the difference in viral replication was abolished in type I IFN receptor knockout cell lines. In conclusion, our results demonstrate that the N588 residue of the NS1 protein is a critical amino acid that promotes viral proliferation by increasing the inhibition of ISGs expression. These insights provide a reference for studying the relationship between parvovirus-mediated inhibition of host innate immunity and viral replication while facilitating improved FPV vaccine production.IMPORTANCEFPV infection is a viral infectious disease with the highest mortality rate in felines. A universal feature of parvovirus is its ability to inhibit host innate immunity, and its ability to suppress innate immunity is mainly accomplished by the NS1 protein. In the present study, FPV was used as a viral model to explore the mechanism by which the NS1 protein inhibits innate immunity and regulates viral replication. Studies have shown that the FPV-NS1 protein containing the N588 residue strongly inhibits the expression of host ISGs, thereby increasing the viral proliferation titer. In addition, the presence of the N588 residue can increase the proliferation titer of the strain 5- to 10-fold without affecting its virulence and immunogenicity. In conclusion, our findings provide new insights and guidance for studying the mechanisms by which parvoviruses suppress innate immunity and for developing high-yielding FPV vaccines.

The Recombinant NS3 Protein a Potential Antigen for Dengue Vaccine Development

The NS3 protein is a multifunctional non-structural protein involved in dengue virus polyprotein processing. This protein is also target in the immune response against dengue virus infection. The predominance of cytotoxic T-cell lymphocytes epitopes in the NS3 structure suggests the participation of this protein in limiting virus replication and in the protection against dengue disease. A brief presentation on aspects related to antigenic characteristics and immunogenicity of the recombinant NS3 protein is reported in this work. A reduced number of studies have assessed the NS3 protein in a dengue vaccine formulation. Researches carried out in mice shown that DNA vaccines based on NS3 protein induced a protective response evaluated by their ability to produce IFNγ. Moreover, the incorporation of recombinant subunit NS3 in a purified inactivated vaccine significantly increased the immune response induced by this inactivated vaccine. Likewise, recent studies demonstrated that the combination of the recombinant modified-NS1 and NS3 proteins from dengue 2 virus induced higher immune responses and protection in mice. The immunological studies discussed herein support the possible inclusion of the NS3 protein in a dengue vaccine formulation.

Prevalence of Powassan Virus Seropositivity Among People with History of Lyme Disease and Non-Lyme Community Controls in the Northeastern United States.

Introduction: Lyme disease (LD) affects ∼476,000 people each year in the United States. Symptoms are variable and include rash and flu-like symptoms. Reasons for the wide variation in disease outcomes are unknown. Powassan virus (POWV) is a tick-borne flavivirus that causes disease ranging from asymptomatic infection to encephalitis, neurologic damage, and death. POWV and LD geographic case distributions overlap, with Ixodes species ticks as the common vectors. Clinical ramifications of coinfection or sequential infection are unknown. Objectives: This study's primary objective was to determine the prevalence of POWV-reactive antibodies in sera samples collected from previously studied cohorts of individuals with self-reported LD history residing in the Northeastern United States. As a secondary objective, we studied clinical differences between people with self-reported LD history and low versus high POWV antibody levels. Methods: We used an enzyme-linked immunosorbent assay (ELISA) to quantify IgG directed at the POWV envelope (E) protein domain III in 538 samples from individuals with self-reported LD history and 16 community controls. The samples were also tested with an ELISA assay to quantify IgG directed at the POWV NS1 protein. Results: The percentage of individuals with LD history and possible evidence of POWV exposure varied depending on the assay utilized. We found no significant difference in clinical symptoms between those with low or high POWV IgG levels in the in-house assay. Congruence of the EDIII and NS1 assays was low with only 12% of those positive in the in-house EDIII ELISA testing positive in the POWV NS1 ELISA. Conclusions: The results highlight the difficulty in flavivirus diagnostic testing, particularly in the retrospective detection of flavivirus exposure. The findings suggest that a prospective study with symptomatic patients using approved clinical testing is necessary to address the incidence and clinical implications of LD and POWV co-infection or sequential infection.

HiBiT-tagged influenza A virus: a stable and efficient tool for antiviral reagent screening and vaccine evaluation

Influenza A viruses (IAVs) possess variable pathogenic potency causing great economic losses in the poultry industry worldwide and threatening public health. The control of IAV epidemics desperately necessitates an efficient platform for screening antiviral compounds and evaluating vaccine efficacy. In this study, we utilized the H9N2 subtype IAV as the working model. An 11-amino-acid HiBiT tag, derived from NanoLuc luciferase, was incorporated into the flexible linker region of the NS1 protein. Subsequently, the recombinant HiBiT-tagged virus was rescued. The recombinant virus exhibited high genetic stability and similar virological characteristics to the parental virus, both in vitro and in vivo. Of particular significance, the replication profile of the HiBiT-tagged virus can be easily measured using the Nano-Glo assay system, achieving an efficient screening platform. Based on this platform, we have developed assays with both convenience and efficiency for screening antiviral reagents, evaluating immunization efficacy, and measuring neutralizing antibodies.

Langat virus inhibits the gp130/JAK/STAT signaling by reducing the gp130 protein level.

The tick-borne encephalitis virus (TBEV) serocomplex includes several medically important flavivirus members endemic to Europe, Asia, and North America, which can induce severe neuroinvasive or viscerotropic diseases with unclear mechanisms of pathogenesis. Langat virus (LGTV) shares a high sequence identity with TBEV but exhibits lower pathogenic potential in humans and serves as a model for virus-host interactions. In this study, we demonstrated that LGTV infection inhibits the activation of gp130/JAK/STAT (Janus kinases (JAK) and signal transducer and activator of transcription (STAT)) signaling, which plays a pivotal role in numerous biological processes. Our data show that the LGTV-infected cells had significantly lower phosphorylated STAT3 (pSTAT3) protein upon oncostatin M (OSM) stimulation than the mock-infected control. LGTV infection blocked the nuclear translocation of STAT3 without a significant effect on total STAT3 protein level. LGTV inhibited JAK1 activation and reduced gp130 protein expression in infected cells, with the viral NS5 protein mediating this effect. TBEV infection also reduces gp130 level. On the other hand, pretreatment of Vero cells with OSM significantly reduces LGTV replication, and STAT1/STAT2 knockdown had little effect on OSM-mediated antiviral effect, which suggests it is independent of STAT1/STAT2 and, instead, it is potentially mediated by STAT3 signlaing. These findings shed light on the LGTV and TBEV-cell interactions, offering insights for the future development of antiviral therapeutics and improved vaccines.

The Phytochemistry profile of Piper betle extract and its Activity Against Hepatitis C Virus

Hepatitis C virus (HCV) is an RNA virus that is easy to mutate and high risk of resistance. The vaccine for HCV has not been provided yet, and the current treatment is very expensive. To provide alternative and complementary antiviral from plants, this study evaluated the activities of Piper betle (P. betle) against HCV and its combination with existing antiviral drugs, Ribavirin and Simeprevir. The antiviral inhibition was identified by in vitro culture using Huh7it-1 cells and JFH1a HCV. Moreover, the phytochemistry profile was also determined by Thin Layer Chromatography (TLC) and High-Performance Liquid Chromatography (HPLC). The result showed that the ethanol extract of P. betle was possess strong activity with an IC50 value of 0.08 ± 0.028 µg/mL. The mechanism of action revealed the extract dominantly inhibit in the post-entry steps. Furthermore, the combination of P. betle extract with simeprevir increased its anti-HCV activity, however, no effect was observed in the combination with ribavirin. The Western blotting analysis was shown inhibition of NS3 protein levels in a dose-dependent manner. Phytochemistry evaluation was shown for the extract containing flavonoids, polyphenols, and alkaloids. These results suggested that the ethanolic extract of P. betle could be a good candidate for the development or an alternative to anti-HCV drugs.
 Keywords: Hepatitis C Virus, Piper betle, Medicinal plants, Simeprevir, Ribavirin, Medicine.

Metagenomic Detection and Genetic Characterization of Human Sapoviruses among Children with Acute Flaccid Paralysis in Nigeria.

Using a metagenomic sequencing approach on stool samples from children with Acute Flaccid Paralysis (AFP), we describe the genetic diversity of Sapoviruses (SaVs) in children in Nigeria. We identified six complete genome sequences and two partial genome sequences. Several SaV genogroups and genotypes were detected, including GII (GII.4 and GII.8), GIV (GIV.1), and GI (GI.2 and GI.7). To our knowledge, this is the first description of SaV infections and complete genomes from Nigeria. Pairwise identity and phylogenetic analysis showed that the Nigerian SaVs were related to previously documented gastroenteritis outbreaks with associated strains from China and Japan. Minor variations in the functional motifs of the nonstructural proteins NS3 and NS5 were seen in the Nigerian strains. To adequately understand the effect of such amino acid changes, a better understanding of the biological function of these proteins is vital. The identification of distinct SaVs reinforces the need for robust surveillance in acute gastroenteritis (AGE) and non-AGE cohorts to better understand SaVs genotype diversity, evolution, and its role in disease burden in Nigeria. Future studies in different populations are, therefore, recommended.

Clinical and seasonal pattern of dengue in a tertiary care hospital of South West India.

Dengue is an emerging global viral disease with an increase 30-fold in incidence in the past fifty years. In the past decade it was restricted to only few a states of South and Northern India but in the recent past it has affected almost all the states in India. The objective of this study was to assess the clinical profile, trends and outcome of dengue cases. This retrospective record based cross-sectional study was conducted in tertiary hospital, Mangaluru in Southern India. The study population included all dengue positive cases diagnosed either by IgM Capture ELISA or Dengue Non-structural Protein NS1 antigen over a period of five years. Information from pre-recorded case sheets were used for data collection. The data was analyzed using SPSS Version 20. Results from the analysis have been expressed in percentages, means and graphs. The study included 401 dengue cases. Most cases were in the age range of 20-40 years with a male to female ratio of 3:2. Overall seropositivity rate was 23.94% with High IgM prevalence. Monthly distribution showed a maximum cases were in the months of June and July and minimum were in January and February. Among the study participants, 91.5% of patients recovered completely and 1.7% of patients had died. 6.8% of patients were discharged against medical advice. Dengue continues to be major public health problem in this part of the globe affecting mainly the working age group. Low seropositivity with High IgM prevelance makes dengue an important differential for febrile illness of vague nature and invokes the need for robust public health response to curb the hyper-endemicity.

Amazon Plant‐Derived Compounds Suppressing Dengue NS5 Protein: Insights from Computational Drug Development and Network Pharmacology Approach

AbstractDengue, a life‐threatening Flavivirus infection, is rampant across 128 tropical and subtropical regions, annually afflicting millions and causing 20,000 deaths due to inadequate treatments. Despite the FDA‐approved Dengvaxia vaccine, its limitations necessitate novel drug development. Notably, the enzymatic nature of the NS5 protein (PDB ID: 3p97) within DENV, responsible for viral RNA synthesis, makes it a prime drug target. Employing Pharmacoinformatics, Molecular Dynamics Simulations, Quantum Mechanics, and network pharmacology, we screened compounds from NuBBE, the Brazilian Amazon Plant Database, along with reported dengue compounds. Docking yielded promising scores (−11.1 to −2.8) and (−11 to −3.1) kcal/mol, respectively. From 1310 phytochemicals, top compounds emerged: Ramosin, Pectolinarin, hinokinin, and sesamin, boasting scores of −11, −11, −9.7, and −9.6, surpassing Acetaminophen's −5.8. Validated post‐docking interactions used 100 ns Molecular Dynamics Simulations and quantum mechanics. Pharmacokinetics and Toxicity analysis aligned with ADME norms, showing no undue toxicity. Network pharmacology unveiled connections between bioactive chemicals and disease targets. This investigation uncovers the potential of these compounds to inhibit DENV‐3 NS5 protein. In vitro, in vivo, and cell line assays are crucial next steps for specific anti‐dengue drug development.

Identification and Genome Characterization of a Novel Muscovy Duck-Origin Goose Parvovirus with Three Recombinant Regions between Muscovy Duck Parvovirus and Goose Parvovirus

Muscovy duck-origin goose parvovirus (MDGPV) is a new virus resulting from the natural recombination of Muscovy duck parvovirus (MDPV) and goose parvovirus (GPV). Previously identified MDGPV strains were found to have two recombination regions, one in the P9 promoter to the NS region and one in the VP3 gene, or only one recombination in the VP3 gene. In 2022, a novel strain of MDGPV known as 2022FZ was identified from China’s mainland. Complete genome sequence analysis showed that there were three recombination regions in this strain: one located in the P9 promoter-NS (425–612 nt) region, one in the NS2 (1,483–1,824 nt) region, and one in the VP3 (3,124–4,248 nt) region, respectively. The recombination regions in the P9 promoter-NS, NS2, and VP3 genes were substituted with the relevant GPVs sequences, whereas the MDPV virulent strain served as the skeleton in this instance. In addition, the 2022FZ strain had multiple unique aa mutations in the NS protein and the VP protein. The Muscovy duckling challenge test showed that MDGPV-2022FZ is less pathogenic to Muscovy ducklings than two recombinant or sole recombinant MDGPV strains. For the first time, our study identified a three-region recombinant MDGPV strain and detected the novel recombination event in the NS2 gene. These results contribute to our understanding of the pathogenicity and genetic diversity of duck parvovirus.

Point-of-care dengue detection: polydopamine-modified electrode for rapid NS1 protein testing for clinical samples.

Early diagnosis of dengue infection by detecting thedengue virus non-structural protein 1 (DENV-NS1) is important to the patients to initiate speedy treatment. Enzyme-linked immunosorbent assay (ELISA)-based NS1 detection and RT-PCR are time-consuming and too complex to be employed in remote areas of dengue-endemic countries. Meanwhile, those of NS1 rapid test by lateral flow assay suffer from low detection limit. Electrochemical-based biosensors using screen-printed gold electrodes (SPGEs) have become a reliable detection method to convey both ELISA's high sensitivity and rapid test portability. In this research, we developed an electrochemical biosensor for DENV-NS1 detection by employing polydopamine (PDA)-modified SPGE. The electrodeposition of PDA on the surface of SPGE serves as a bioconjugation avenue for anti-NS1 antibody through a simple and low-cost immobilization procedure. The biosensor performance was evaluated to detect DENV-NS1 protein in PBS and human serum through a differential pulse voltammetric (DPV) technique. The developed sensing platform displayed a low limit of detection (LOD) of 1.63pgmL-1 and a wide linear range of 10pgmL-1 to 1ngmL-1 (R2 ∼ 0.969). The sensing platform also detected DEV-NS1 from four different serotypes in the clinical samples collected from dengue patients in India and Indonesia, with acceptable sensitivity, specificity, and accuracy values of 90.00%, 80.95%, and 87.65%, respectively. This result showcased the facile and versatile method of PDA coating onto the surface of screen-printed gold electrodes for a miniaturized point-of-care (PoC) detection device.