Comparative Flavivirus-Host Protein Interaction Mapping Reveals Mechanisms of Dengue and Zika Virus Pathogenesis.

Mosquito-borne flaviviruses, including dengue virus (DENV) and Zika virus (ZIKV), are a growing public health concern. Systems-level analysis of how flaviviruses hijack cellular processes through virus-host protein-protein interactions (PPIs) provides information about their replication and pathogenic mechanisms. We used affinity purification-mass spectrometry (AP-MS) to compare flavivirus-host interactions for two viruses (DENV and ZIKV) in two hosts (human and mosquito). Conserved virus-host PPIs revealed that the flavivirus NS5 protein suppresses interferon stimulated genes by inhibiting recruitment of the transcription complex PAF1C and that chemical modulation of SEC61 inhibits DENV and ZIKV replication in human and mosquito cells. Finally, we identified a ZIKV-specific interaction between NS4A and ANKLE2, a gene linked to hereditary microcephaly, and showed that ZIKV NS4A causes microcephaly in Drosophila in an ANKLE2-dependent manner. Thus, comparative flavivirus-host PPI mapping provides biological insights and, when coupled with in vivo models, can be used to unravel pathogenic mechanisms.

Targeting Viral Proteostasis Limits Influenza Virus, HIV, and Dengue Virus Infection.

Viruses are obligate parasites and thus require the machinery of the host cell to replicate. Inhibition of host factors co-opted during active infection is a strategy hosts use to suppress viral replication and a potential pan-antiviral therapy. To define the cellular proteins and processes required for a virus during infection is thus crucial to understanding the mechanisms of virally induced disease. In this report, we generated fully infectious tagged influenza viruses and used infection-based proteomics to identify pivotal arms of cellular signaling required for influenza virus growth and infectivity. Using mathematical modeling and genetic and pharmacologic approaches, we revealed that modulation of Sec61-mediated cotranslational translocation selectively impaired glycoprotein proteostasis of influenza as well as HIV and dengue viruses and led to inhibition of viral growth and infectivity. Thus, by studying virus-human protein-protein interactions in the context of active replication, we have identified targetable host factors for broad-spectrum antiviral therapies.

Adropin, a novel hepatokine: localization and expression during postnatal development and its impact on testicular functions of pre-pubertal mice.

Adropin, a multifaceted peptide, was identified as a new metabolic hormone responsible for regulating gluco-lipid homeostasis. However, its role in the testicular function is not yet understood. We aimed to investigate the localization and expression of adropin and GPR19 during different phases of postnatal development. Immunohistochemical study revealed the intense reactivity of adropin in the Leydig cells during all phases of postnatal development, while GPR19 showed intense immunoreactivity in the pachytene spermatocytes and mild immunoreactivity in Leydig cells as well as primary and secondary spermatocytes. Western blot study revealed maximum expression of GPR19 in pre-pubertal mouse testis that clearly indicates maximum responsiveness of adropin during that period. So, we hypothesized that adropin may act as an autocrine/paracrine factor that regulates pubertal changes in mouse testis. To examine the effect of adropin on pubertal onset, we gave bilateral intra-testicular doses (0.5 and 1.5 µg/testis) to pre-pubertal mice. Adropin treatment promoted testicular testosterone synthesis by increasing the expression of StAR, 3ß-HSD, and 17ß-HSD. Adropin also promoted germ cell survival and proliferation by upregulating the expression of PCNA and downregulating the Bax/Bcl2 ratio and Caspase 3 expression resulting in fewer TUNEL-positive cells in adropin-treated groups. FACS analysis demonstrated that adropin treatment not only increases 1C to 4C ratio but also significantly increases the 1C (spermatid) and 1C to 2C ratio which demarcates accelerated germ cell differentiation and turnover of testicular cells. In conclusion, adropin promotes steroidogenesis, germ cell survival, as well as the proliferation in the pre-pubertal mouse testis that may hasten the pubertal transition in an autocrine/paracrine manner.

From A to E: Uniting vitamins against stroke risk-A systematic review and network meta-analysis.

BACKGROUND AND AIM: Stroke represents a significant public health challenge, necessitating the exploration of preventive measures. This network meta-analysis aimed to assess the efficacy of different vitamin treatments compared to a placebo in preventing stroke. METHODS: A systematic electronic search in databases including PubMed, EmBASE, Web of Science, clinicaltrials.gov, and Google Scholar until 31 May 2023 was conducted, to identify published studies investigating the association between vitamin intake and the risk of stroke. Pooled risk ratio (RR) with 95% confidence intervals (CIs) was calculated using a frequentist network meta-analysis. Furthermore, we ranked vitamins based on p-scores, facilitating a comparative assessment of their effectiveness in preventing stroke. RESULTS: A total of 56 studies, including 17 randomized controlled trials (RCTs) and 39 cohort studies were analyzed. Direct estimates obtained from network meta-analysis, we found that vitamin A (RR: .81 [.72-.91]), vitamin B-complex (RR: .85 [.74-.97]), vitamin B6 (RR: 79 [.68-.92]), folate (RR: .86 [.75-.97]), vitamin C (RR: .77 [.70-.85]) and vitamin D (RR: .73 [.64-.83]) were significantly associated with a decreased stroke risk. However, no significant association was observed for vitamin B2, vitamin B12, and vitamin E. Subsequent to network meta-analysis, vitamins were ranked in decreasing order of their efficacy in stroke prevention based on p-score, with vitamin D (p-score = .91), vitamin C (p-score = .79), vitamin B6 (p-score = .70), vitamin A (p-score = .65), vitamin B-complex (p-score = .53), folate (p-score = .49), vitamin B2 (p-score = .39), vitamin E (p-score = .28), vitamin B12 (.13) and placebo (.10). CONCLUSION: Our study has established noteworthy connections between vitamin A, vitamin B-complex, vitamin B6, folate, vitamin C, and vitamin D in the realm of stroke prevention. These findings add substantial weight to the accumulating evidence supporting the potential advantages of vitamin interventions in mitigating the risk of stroke. However, to solidify and validate these observations, additional research is imperative. Well-designed clinical trials or cohort studies are needed to further explore these associations and formulate clear guidelines for incorporating vitamin supplementation into effective stroke prevention strategies.

Restoration of the soil fertility under Cr(VI) and artificial drought condition by the utilization of plant growth-promoting Bacillus spp. SSAU2.

The study explores the potential of an indigenous halo-tolerant microbe identified as Bacillus spp. SSAU-2 in enhancing soil fertility and promoting plant growth for sustainable agricultural practices under the influence of multiple abiotic stresses such as Cr(VI), high salinity, and artificial drought condition. The study investigated various factors influencing IAA synthesis by SSAU-2, such as pH (5 to 11), salinity (10 to 50 g/L), tryptophan concentration (0.5 to 1%), carbon (mannitol mand lactose), and nitrogen sources (peptone and tryptone). The highest IAA concentration was observed at pH 10 (1.695 mg/ml) and pH 11 (0.782 mg/ml). IAA synthesis was optimized at a salinity level of 30 g/l, with lower and higher salinity levels resulting in decreased IAA concentrations. Notably, the presence of mannitol and lactose significantly augmented IAA synthesis, while glucose and sucrose had inhibitory effects. Furthermore, peptone and tryptone played a pivotal role in enhancing IAA synthesis, while ammonium chloride exerted an inhibitory influence. SSAU-2 showed a diverse array of capabilities, including the synthesis of gibberellins, extracellular polymeric substances, siderophores, and hydrogen cyanide along with nitrogen fixation and ammonia production. The microbe could efficiently tolerate 45% PEG-6000 concentration and effectively produce IAA in 15% PEG concentration. It could also tolerate high concentration of Cr(VI) and synthesize IAA even in 50 ppm Cr(VI). The findings of this study provide valuable insights into harnessing the potential of indigenous microorganisms to promote plant growth, enhance soil fertility, and establish sustainable agricultural practices essential for restoring the health of ecosystems.

SARS-CoV-2 ORF6 protein targets TRIM25 for proteasomal degradation to diminish K63-linked RIG-I ubiquitination and type-I interferon induction.

Evasion and antagonism of host cellular immunity upon SARS-CoV-2 infection provide replication advantage to the virus and contribute to COVID-19 pathogenesis. We explored the ability of different SARS-CoV-2 proteins to antagonize the host's innate immune system and found that the ORF6 protein mitigated type-I Interferon (IFN) induction and downstream IFN signaling. Our findings also corroborated previous reports that ORF6 blocks the nuclear import of IRF3 and STAT1 to inhibit IFN induction and signaling. Here we show that ORF6 directly interacts with RIG-I and blocks downstream type-I IFN induction and signaling by reducing the levels of K63-linked ubiquitinated RIG-I. This involves ORF6-mediated targeting of E3 ligase TRIM25 for proteasomal degradation, which was also observed during SARS-CoV-2 infection. The type-I IFN antagonistic activity of ORF6 was mapped to its C-terminal cytoplasmic tail, specifically to amino acid residues 52-61. Overall, we provide new insights into how SARS-CoV-2 inhibits type-I IFN induction and signaling through distinct actions of the viral ORF6 protein.

Bioengineering Strategies for Developing Vaccines against Respiratory Viral Diseases.

Respiratory viral pathogens like influenza and coronaviruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have caused outbreaks leading to millions of deaths. Vaccinations are, to date, the best and most economical way to control such outbreaks and have been highly successful for several pathogens. Currently used vaccines for respiratory viral pathogens are primarily live attenuated or inactivated and can risk reversion to virulence or confer inadequate immunity. The recent trend of using potent biomolecules like DNA, RNA, and protein antigenic components to synthesize vaccines for diseases has shown promising results. Still, it remains challenging to translate due to their high susceptibility to degradation during storage and after delivery. Advances in bioengineering technology for vaccine design have made it possible to control the physicochemical properties of the vaccines for rapid synthesis, heightened antigen presentation, safer formulations, and more robust immunogenicity. Bioengineering techniques and materials have been used to synthesize several potent vaccines, approved or in trials, against coronavirus disease 2019 (COVID-19) and are being explored for influenza, SARS, and Middle East respiratory syndrome (MERS) vaccines as well. Here, we review bioengineering strategies such as the use of polymeric particles, liposomes, and virus-like particles in vaccine development against influenza and coronaviruses and the feasibility of adopting these technologies for clinical use.

Incidental detection of rare vascular variation during pyeloplasty and its clinical implication - A case report.

ABSTRACT: Crossing vessels is one of the important causes of pelviureteric junction obstruction (PUJO). Accessory lower polar vessels are commonly seen with congenital PUJO, but they are not always the cause of obstruction. We incidentally encountered a variation in the lower polar crossing vessel while doing laparoscopic pyeloplasty in a patient with congenital PUJO. We encountered a right accessory lower polar artery and vein along with a right gonadal artery arising from the accessory right renal artery and right gonadal vein draining into the right lower polar crossing accessory renal vein. Knowledge of variations in genitourinary vasculature is important in the current era to prevent inadvertent complications.

Enhanced recombination among Omicron subvariants of SARS-CoV-2 contributes to viral immune escape.

Genetic recombination is an important driver of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) evolution, which requires the coinfection of a single host cell with different SARS-CoV-2 strains. To understand the emergence and prevalence of recombinant SARS-CoV-2 lineages through time and space, we analyzed SARS-CoV-2 genome sequences collected from November 2019 to July 2022. We observed an extraordinary increase in the emergence of SARS-CoV-2 recombinant lineages during the Omicron wave, particularly in Northern America and Europe. This phenomenon was independent of the sequencing frequency or genetic diversity of circulating SARS-CoV-2 strains. The recombination breakpoints were more prevalent in the 3'-untranslated region of the viral genome. Importantly, we noted the enrichment of certain amino acids in the Spike protein of recombinant lineages, which have been reported to confer immune escape from neutralizing antibodies and increase angiotensin-converting enzyme 2 receptor binding in some cases. We also observed I42V amino acid change genetically fixated in the NSP14 of the Omicron lineage, which needs further characterization for its potential role in enhanced recombination. Overall, we report the important and timely observation of accelerated recombination in the currently circulating SARS-CoV-2 Omicron variants and explore their potential contribution to viral fitness, particularly immune escape.

Innate Immune Subversion Strategies of Human Flaviviruses.

Flavivirus is a genus of medically important viruses, including Dengue virus (DENV), Zika virus (ZIKV), Yellow Fever virus (YFV), West Nile virus (WNV), Japanese encephalitis virus (JEV), etc. The global burden of these acute infection-causing viruses is ever-increasing. Primary febrile symptoms of most of these viruses can progress to hemorrhagic or neurological complications, and some like JEV, YFV have a greater than 15% mortality. The absence of antiviral therapy and highly effective vaccine candidates for these viruses highlights the need for research into virulence and immune evasion mechanisms at the molecular level. Interaction with the host needs to be carefully dissected to narrow down to a list of necessary factors for virus survival within the host. This review attempts to comprehensively compile research efforts made in the field of innate immune subversion strategies employed by the human Flaviviruses.

Copper-Catalyzed Oxidative [3 + 2]-Annulation of Quinoxalin-2(1H)-one with Oxime Esters toward Functionalized Pyrazolo[1,5-a]quinoxalin-4(5H)-ones as Opioid Receptor Modulators.

Pyrazolo[1,5-a]quinoxalin-4(5H)-one derivatives as novel opioid receptor modulators have been synthesized via copper-catalyzed oxidative [3 + 2]-annulation of quinoxalin-2(1H)-one and oxime-O-acetates. This hydrazine-free C-C and N-N bond formation strategy starts with the generation of C2N1 synthon using oxime acetate, which reacts in a [3 + 2] manner with quinoxalin-2(1H)-one, followed by oxidative aromatization. The synthesized compounds were tested against opioid receptors, of which eight compounds exhibited an antagonistic effect with EC50 < 5 µM at various opioid receptors. Molecular docking studies were performed to identify the binding of active pyrazolo[1,5-a]quinoxalin-4(5H)-one ligands with hKOR protein. Docking results indicated that compounds 3d and 3g participate in hydrogen bonding with the hydroxyl group of T111 of the active site pocket residue.

The ETS transcription factor ELF1 regulates a broadly antiviral program distinct from the type I interferon response.

Induction of vast transcriptional programs is a central event of innate host responses to viral infections. Here we report a transcriptional program with potent antiviral activity, driven by E74-like ETS transcription factor 1 (ELF1). Using microscopy to quantify viral infection over time, we found that ELF1 inhibits eight diverse RNA and DNA viruses after multi-cycle replication. Elf1 deficiency results in enhanced susceptibility to influenza A virus infections in mice. ELF1 does not feed-forward to induce interferons, and ELF1's antiviral effect is not abolished by the absence of STAT1 or by inhibition of JAK phosphorylation. Accordingly, comparative expression analyses by RNA-seq revealed that the ELF1 transcriptional program is distinct from interferon signatures. Thus, ELF1 provides an additional layer of the innate host response, independent from the action of type I interferons.

Impact of mandibular third molars on angle fractures: A retrospective study.

BACKGROUND: Previous studies have shown that the position and presence of mandibular third molars is associated with a high risk of mandibular angle fractures. The aim of this study was to assess the relationship between the position and presence of mandibular third molars and mandibular angle fractures. MATERIAL AND METHODS: A retrospective study consisting of 256 patients who were admitted for treatment of mandibular fractures between January 2016 and January 2018 was undertaken. Patients' data and orthopantomogram radiographs were obtained from their medical record. The predictor variable was the presence and position of mandibular third molars. The position of the third molars was grouped based on the Pell and Gregory classification. The outcome variable was the presence of an angle fracture. Other study variables included age, gender, mechanism of injury, and fracture location. RESULTS: Patients with mandibular third molars had a 2.7 times greater chance of an angle fracture than patients without third molars. Patients with their third molars present at occlusal position C and ramus position level 3 had a higher risk of angle fracture in comparison with other groups. There was a statistically significant variation in the risk of an angle fracture, depending on mandibular third molar position (P < .001). CONCLUSION: Patients with mandibular third molars have an increased risk of angle fractures. The risk for an angle fracture varied depending on the third molar position.

A Comparative Synthetic Strategy Perspective on α-Amino Acid- and Non-Amino Acid-Derived Synthons towards Total Syntheses of Selected Natural Macrolides.

Macrocyclic alkaloids (macrolides) and cyclopeptides have an immense range of applications in drug discovery research because of their natural abundance and potential biological and physicochemical properties. Presently, more than 100 approved drugs or clinical drug candidates contain macrocyclic scaffolds as the biologically active component. This review provides an interesting perspective about the use of amino acid-derived chiral pools versus other methods derived from miscellaneous synthons towards the total synthesis of non-peptidic macrolides. The synthetic routes and the key strategies involved in the total syntheses of ten natural macrolides have been discussed. Both the amino acid-derived and non-amino acid-derived synthetic routes have been illustrated to present a comparative study between the two approaches.

Construction of Highly Functionalized Piperazinones via Post-Ugi Cyclization and Diastereoselective Nucleophilic Addition.

A novel method for the generation of uniquely functionalized piperazinones by utilizing post-Ugi functionalization is described. The method involves an Ugi reaction with aminoacetaldehyde dimethyl acetal, followed by acid-mediated cyclization to generate the iminium precursor that was subjected to nucleophilic addition in a diastereoselective manner. The method was also employed to synthesize trans-dragmacidine C and praziquantel-like molecules.

Right ventricular dysfunction in rheumatic heart valve disease: A clinicopathological evaluation.

Background: . Dysfunction of the right ventricle (RV) in rheumatic heart disease (RHD) is a poor prognostic factor. We planned to observe the clinicopathological changes in the RV of patients with RHD. Methods: . We defined RV dysfunction by a myocardial performance index value of >0.4 on transthoracic echo-cardiography and included patients with isolated severe mitral stenosis in sinus rhythm with normal left ventricular (LV) function from April 2014 to April 2016. The patients were divided into two groups based on the absence (group I, n=21) and presence (group II, n=22) of RV dysfunction. RV muscle biopsy was evaluated for the presence of apoptosis, fibrosis and fat deposition apart from other clinical and echocardiography parameters. Results: . Patients in both the groups had a similar demographic profile and LV dimensions and function. The age of the patients in the two groups was the only clinical parameter that was significantly different; older patients were in group II. A higher value for RV systolic pressure (RVSP) and the grade of tricuspid regurgitation was seen in group II. Though there was no significant difference in the presence of fibrosis and intensity of apoptosis in the RV biopsy samples, the deposition of fat in the interstitial spaces was decreased in group II. Age at presentation had no significant difference or correlation with the deposition of fibrosis or fat in the RV myocardial biopsy. Conclusions: . Patients with RV dysfunction were older in age and their RVSP was raised at operation, suggesting that earlier intervention may help in preserving RV function.

Specific Mutations in the PB2 Protein of Influenza A Virus Compensate for the Lack of Efficient Interferon Antagonism of the NS1 Protein of Bat Influenza A-Like Viruses.

Recently, two new influenza A-like viruses have been discovered in bats, A/little yellow-shouldered bat/Guatemala/060/2010 (HL17NL10) and A/flat-faced bat/Peru/033/2010 (HL18NL11). The hemagglutinin (HA)-like (HL) and neuraminidase (NA)-like (NL) proteins of these viruses lack hemagglutination and neuraminidase activities, despite their sequence and structural homologies with the HA and NA proteins of conventional influenza A viruses. We have now investigated whether the NS1 proteins of the HL17NL10 and HL18NL11 viruses can functionally replace the NS1 protein of a conventional influenza A virus. For this purpose, we generated recombinant influenza A/Puerto Rico/8/1934 (PR8) H1N1 viruses containing the NS1 protein of the PR8 wild-type, HL17NL10, and HL18NL11 viruses. These viruses (r/NS1PR8, r/NS1HL17, and r/NS1HL18, respectively) were tested for replication in bat and nonbat mammalian cells and in mice. Our results demonstrate that the r/NS1HL17 and r/NS1HL18 viruses are attenuated in vitro and in vivo However, the bat NS1 recombinant viruses showed a phenotype similar to that of the r/NS1PR8 virus in STAT1-/- human A549 cells and mice, both in vitro and in vivo systems being unable to respond to interferon (IFN). Interestingly, multiple mouse passages of the r/NS1HL17 and r/NS1HL18 viruses resulted in selection of mutant viruses containing single amino acid mutations in the viral PB2 protein. In contrast to the parental viruses, virulence and IFN antagonism were restored in the selected PB2 mutants. Our results indicate that the NS1 protein of bat influenza A-like viruses is less efficient than the NS1 protein of its conventional influenza A virus NS1 counterpart in antagonizing the IFN response and that this deficiency can be overcome by the influenza virus PB2 protein.IMPORTANCE Significant gaps in our understanding of the basic features of the recently discovered bat influenza A-like viruses HL17NL10 and HL18NL11 remain. The basic biology of these unique viruses displays both similarities to and differences from the basic biology of conventional influenza A viruses. Here, we show that recombinant influenza A viruses containing the NS1 protein from HL17NL10 and HL18NL11 are attenuated. This attenuation was mediated by their inability to antagonize the type I IFN response. However, this deficiency could be compensated for by single amino acid replacements in the PB2 gene. Our results unravel a functional divergence between the NS1 proteins of bat influenza A-like and conventional influenza A viruses and demonstrate an interplay between the viral PB2 and NS1 proteins to antagonize IFN.

A novel Zika virus mouse model reveals strain specific differences in virus pathogenesis and host inflammatory immune responses.

Zika virus (ZIKV) is a mosquito borne flavivirus, which was a neglected tropical pathogen until it emerged and spread across the Pacific Area and the Americas, causing large human outbreaks associated with fetal abnormalities and neurological disease in adults. The factors that contributed to the emergence, spread and change in pathogenesis of ZIKV are not understood. We previously reported that ZIKV evades cellular antiviral responses by targeting STAT2 for degradation in human cells. In this study, we demonstrate that Stat2-/- mice are highly susceptible to ZIKV infection, recapitulate virus spread to the central nervous system (CNS), gonads and other visceral organs, and display neurological symptoms. Further, we exploit this model to compare ZIKV pathogenesis caused by a panel of ZIKV strains of a range of spatiotemporal history of isolation and representing African and Asian lineages. We observed that African ZIKV strains induce short episodes of severe neurological symptoms followed by lethality. In comparison, Asian strains manifest prolonged signs of neuronal malfunctions, occasionally causing death of the Stat2-/- mice. African ZIKV strains induced higher levels of inflammatory cytokines and markers associated with cellular infiltration in the infected brain in mice, which may explain exacerbated pathogenesis in comparison to those of the Asian lineage. Interestingly, viral RNA levels in different organs did not correlate with the pathogenicity of the different strains. Taken together, we have established a new murine model that supports ZIKV infection and demonstrate its utility in highlighting intrinsic differences in the inflammatory response induced by different ZIKV strains leading to severity of disease. This study paves the way for the future interrogation of strain-specific changes in the ZIKV genome and their contribution to viral pathogenesis.

Interplay between influenza A virus and host factors: targets for antiviral intervention.

Influenza A viruses (IAVs) pose a major public health threat worldwide. Recent experience with the 2013 H7N9 outbreak in China and the 2009 "swine flu" pandemic have shown that antiviral vaccines and drugs fall short of controlling the spread of disease in a timely and effective manner. Major problems include rapid emergence of drug-resistant influenza virus strains and the slow process of vaccine production. With the threat of a highly pathogenic H5N1 bird-flu pandemic looming large, it is crucial to develop novel ways of combating influenza A viruses. Targeting the host factors critical for influenza A virus replication has shown promise as a strategy to develop novel antiviral molecules with broad-spectrum protection. In this review, we summarize the role of currently identified host factors that play a critical role in the influenza A virus life cycle and discuss the most promising candidates for anti-influenza therapeutics.