Mouse hepatitis virus JHMV I protein is required for maximal virulence.

Betacoronaviruses encode a conserved accessory gene within the +1 open reading frame (ORF) of nucleocapsid called the internal N gene. This gene is referred to as "I" for mouse hepatitis virus (MHV), ORF9b for severe acute respiratory CoV (SARS-CoV) and SARS-CoV-2, and ORF8b for Middle East respiratory syndrome CoV (MERS-CoV). Previous studies have shown ORF8b and ORF9b have immunoevasive properties, while the only known information for MHV I is its localization within the virion of the hepatotropic/neurotropic A59 strain of MHV. Whether MHV I is an innate immune antagonist or has other functions has not been evaluated. In this report, we show that the I protein of the neurotropic JHM strain of MHV (JHMV) lacks a N terminal domain present in other MHV strains, has immunoevasive properties, and is a component of the virion. Genetic deletion of JHMV I (rJHMVIΔ57-137) resulted in a highly attenuated virus both in vitro and in vivo that displayed a post RNA replication/transcription defect that ultimately resulted in fewer infectious virions packaged compared with wild-type virus. This phenotype was only seen for rJHMVIΔ57-137, suggesting the structural changes predicted for A59 I altered its function, as genetic deletion of A59 I did not change viral replication or pathogenicity. Together, these data show that JHMV I both acts as a mild innate immune antagonist and aids in viral assembly and infectious virus production, and suggest that the internal N proteins from different betacoronaviruses have both common and virus strain-specific properties.IMPORTANCECoV accessory genes are largely studied in overexpression assays and have been identified as innate immune antagonists. However, functions identified after overexpression are often not confirmed in the infected animal host. Furthermore, some accessory proteins are components of the CoV virion, but their role in viral replication and release remains unclear. Here, we utilized reverse genetics to abrogate expression of a conserved CoV accessory gene, the internal N ("I") gene, of the neurotropic JHMV strain of MHV and found that loss of the I gene resulted in a post replication defect that reduced virion assembly and ultimately infectious virus production, while also increasing some inflammatory molecule expression. Thus, the JHMV I protein has roles in virion assembly that were previously underappreciated and in immunoevasion.

Chromatin Regulator SMARCA4 Is Essential for MHV-Induced Inflammatory Cell Death, PANoptosis.

The innate immune system serves as the first line of defense against ß-coronaviruses (ß-CoVs), a family of viruses that includes SARS-CoV-2. Viral sensing via pattern recognition receptors triggers inflammation and cell death, which are essential components of the innate immune response that facilitate viral clearance. However, excessive activation of the innate immune system and inflammatory cell death can result in uncontrolled release of proinflammatory cytokines, resulting in cytokine storm and pathology. PANoptosis, innate immune, inflammatory cell death initiated by innate immune sensors and driven by caspases and RIPKs through PANoptosome complexes, has been implicated in the pathology of viral infections. Therefore, understanding the molecular mechanisms regulating PANoptosis in response to ß-CoV infection is critical for identifying new therapeutic targets that can mitigate disease severity. In the current study, we analyzed findings from a cell death-based CRISPR screen with archetypal ß-CoV mouse hepatitis virus (MHV) as the trigger to characterize host molecules required for inflammatory cell death. As a result, we identified SMARCA4, a chromatin regulator, as a putative host factor required for PANoptosis in response to MHV. Furthermore, we observed that gRNA-mediated deletion of Smarca4 inhibited MHV-induced PANoptotic cell death in macrophages. These findings have potential translational and clinical implications for the advancement of treatment strategies for ß-CoVs and other infections.

Development of two novel on-site detection visualization methods for murine hepatitis virus based on the multienzyme isothermal rapid amplification.

Murine hepatitis virus (MHV) infection is one of the most prevalent types of mice infection in laboratory. MHV could cause death in mice and even interfere with the results in animal experiments. Herein, we developed two isothermal approaches based on the Multienzyme Isothermal Rapid Amplification (MIRA), for rapid detection of MHV in conserved M gene. We designed and screened several pairs of primers and probes and the isothermal fluorescence detector was applied for the exonuclease Ⅲ reverse transcription MIRA (exo-RT-MIRA) assay. To further simplify the workflow, the portable fluorescence visualization instrument, also as a palm-sized handheld system, was used for the naked-eye exo-RT-MIRA assay. The amplification temperature and time were optimized. The assay could be processed well at 42 °C 20 min for the exo-RT-MIRA and the naked-eye exo-RT-MIRA assay. The limit of detection (LoD) of the exo-RT-MIRA assay was 43.4 copies/µL. The LoD of the naked-eye exo-RT-MIRA assay was 68.2 copies/µL. No nonspecific amplifications were observed in the two assays. A total of 107 specimens were examined by qPCR and two assays developed. The experimental results statistical analysis demonstrated that the exo-RT-MIRA assay with the qPCR yielded sufficient agreement with a kappa value of 1.000 (p < 0.0001). The results also exhibited a good agreement (kappa value, 0.961) (p < 0.0001) between the naked-eye exo-RT-MIRA assay and the qPCR assay. In our study, the exo-RT-MIRA assay and the naked-eye exo-RT-MIRA assay presented the possibility of new methods in MHV point-of-testing diagnosis.

Advancing Hepatitis C Elimination in Africa: Insights from Egypt.

The hepatitis C virus (HCV) poses a significant risk to global public health and is linked to life-threatening clinical outcomes. According to the WHO, there are an estimated 58 million people worldwide who have a chronic hepatitis C virus (HCV) infection; there are 1.5 million new cases and more than 350,000 fatalities from HCV-related illnesses each year. Even though there are numerous diagnostic techniques, the lack of funding, inadequate healthcare infrastructure, and low public awareness of the Hepatitis C virus can make diagnosis and treatment difficult to obtain throughout the continent. The frequency of hepatitis C virus infection is highest in African nations (1-26%), raising serious concerns about the virus's impact on public health. The world's highest rate of Hepatitis C virus infection was found in Egypt, an African nation. Its nationwide hepatitis C elimination program stands out as a prime example of achievement, having screened, and treated over 60 million people, significantly reducing the disease's incidence and prevalence. Other African nations facing similar difficulties might benefit greatly from Egypt's methods, which provide valuable insights and flexible frameworks. This review aims to shed light on Egypt's successes and challenges while offering strategic recommendations to African nations to quicken their progress in eliminating hepatitis C.

Decay of RNA and infectious SARS-CoV-2 and murine hepatitis virus in wastewater.

Wastewater-based epidemiology (WBE) has been an important tool for population surveillance during the COVID-19 pandemic and continues to play a key role in monitoring SARS-CoV-2 infection levels following reductions in national clinical testing schemes. Studies measuring decay profiles of SARS-CoV-2 in wastewater have underscored the value of WBE, however investigations have been hampered by high biosafety requirements for SARS-CoV-2 infection studies. Therefore, surrogate viruses with lower biosafety standards have been used for SARS-CoV-2 decay studies, such as murine hepatitis virus (MHV), but few studies have directly compared decay rates of both viruses. We compared the persistence of SARS-CoV-2 and MHV in wastewater, using 50 % tissue culture infectious dose (TCID50) and reverse transcription quantitative polymerase chain reaction (RT-qPCR) assays to assess infectious virus titre and viral gene markers, respectively. Infectious SARS-CoV-2 and MHV indicate similar endpoints, however observed early decay characteristics differed, with infectious SARS-CoV-2 decaying more rapidly than MHV. We find that MHV is an appropriate infectious virus surrogate for viable SARS-CoV-2, however inconsistencies exist in viral RNA decay parameters, indicating MHV may not be a suitable nucleic acid surrogate across certain temperature regimes. This study highlights the importance of sample preparation and the potential for decay rate overestimation in wastewater surveillance for SARS-CoV-2 and other pathogens.

Acute and Long COVID Intestinal Changes in an Experimental Model of Coronavirus in Mice.

The COVID-19 pandemic, which emerged in early 2020, has had a profound and lasting impact on global health, resulting in over 7.0 million deaths and persistent challenges. In addition to acute concerns, there is growing attention being given to the long COVID health consequences for survivors of COVID-19 with documented cases of cardiovascular abnormalities, liver disturbances, lung complications, kidney issues, and noticeable cognitive deficits. Recent studies have investigated the physiological changes in various organs following prolonged exposure to murine hepatitis virus-1 (MHV-1), a coronavirus, in mouse models. One significant finding relates to the effects on the gastrointestinal tract, an area previously understudied regarding the long-lasting effects of COVID-19. This research sheds light on important observations in the intestines during both the acute and the prolonged phases following MHV-1 infection, which parallel specific changes seen in humans after exposure to SARS-CoV-2. Our study investigates the histopathological alterations in the small intestine following MHV-1 infection in murine models, revealing significant changes reminiscent of inflammatory bowel disease (IBD), celiac disease. Notable findings include mucosal inflammation, lymphoid hyperplasia, goblet cell hyperplasia, and immune cell infiltration, mirroring pathological features observed in IBD. Additionally, MHV-1 infection induces villous atrophy, altered epithelial integrity, and inflammatory responses akin to celiac disease and IBD. SPIKENET (SPK) treatment effectively mitigates intestinal damage caused by MHV-1 infection, restoring tissue architecture and ameliorating inflammatory responses. Furthermore, investigation into long COVID reveals intricate inflammatory profiles, highlighting the potential of SPK to modulate intestinal responses and restore tissue homeostasis. Understanding these histopathological alterations provides valuable insights into the pathogenesis of COVID-induced gastrointestinal complications and informs the development of targeted therapeutic strategies.

Detection of Equine Parvovirus-Hepatitis Virus and Equine Hepacivirus in Archived Sera from Horses in France and Australia.

Reports of newly discovered equine hepatotropic flavi- and parvoviruses have emerged throughout the last decade in many countries, the discovery of which has stimulated a great deal of interest and clinical research. Although commonly detected in horses without signs of disease, equine parvovirus hepatitis (EqPV-H) and equine hepacivirus (EqHV) have been associated with liver disease, including following the administration of contaminated anti-toxin. Our aim was to determine whether EqPV-H and EqHV are present in Australian horses and whether EqPV-H was present in French horses and to examine sequence diversity between strains of both viruses amongst infected horses on either side of the globe. Sera from 188 Australian horses and 256 French horses from horses with and without clinical signs of disease were collected. Twelve out of 256 (4.7%) and 6 out of 188 (3.2%) French and Australian horses, respectively, were positive for the molecular detection of EqPV-H. Five out of 256 (1.9%) and 21 out of 188 (11.2%) French and Australian horses, respectively, were positive for the molecular detection of EqHV. Australian strains for both viruses were genomically clustered, in contrast to strains from French horses, which were more broadly distributed. The findings of this preliminary survey, with the molecular detection of EqHV and EqPV-H in Australia and the latter in France, adds to the growing body of awareness regarding these recently discovered hepatotropic viruses. It has provided valuable information not just in terms of geographic endemicity but will guide equine clinicians, carers, and authorities regarding infectious agents and potential impacts of allogenic tissue contamination. Although we have filled many gaps in the world map regarding equine hepatotropic viruses, further prospective studies in this emerging field may be useful in terms of elucidating risk factors and pathogenesis of these pathogens and management of cases in terms of prevention and diagnosis.

Key role of interferon regulatory factor 1 (IRF-1) in regulating liver disease: progress and outlook. / IRF-1åœ¨è‚è„ç–¾ç— è°ƒæŽ§ä¸­çš„å ³é”®ä½œç”¨ï¼šè¿›å±•ä¸Žå±•æœ›.

Interferon regulatory factor 1 (IRF-1) is a member of the IRF family. It is the first transcription factor to be identified that could bind to the interferon-stimulated response element (ISRE) on the target gene and displays crucial roles in the interferon-induced signals and pathways. IRF-1, as an important medium, has all of the advantages of full cell cycle regulation, cell death signaling transduction, and reinforcing immune surveillance, which are well documented. Current studies indicate that IRF-1 is of vital importance to the occurrence and evolution of multifarious liver diseases, including but not limited to inhibiting the replication of the hepatitis virus (A/B/C/E), alleviating the progression of liver fibrosis, and aggravating hepatic ischemia-reperfusion injury (HIRI). The tumor suppression of IRF-1 is related to the clinical characteristics of liver cancer patients, which makes it a potential indicator for predicting the prognosis and recurrence of liver cancer; additionally, the latest studies have revealed other effects of IRF-1 such as protection against alcoholic/non-alcoholic fatty liver disease (AFLD/NAFLD), cholangiocarcinoma suppression, and uncommon traits in other liver diseases that had previously received little attention. Intriguingly, several compounds and drugs have featured a protective function in specific liver disease models in which there is significant involvement of the IRF-1 signal. In this paper, we hope to propose a prospective research basis upon which to help decipher translational medicine applications of IRF-1 in liver disease treatment.

Activation of alveolar epithelial ER stress by ß-coronavirus infection disrupts surfactant homeostasis in mice: implications for COVID-19 respiratory failure.

COVID-19 syndrome is characterized by acute lung injury, hypoxemic respiratory failure, and high mortality. Alveolar type 2 (AT2) cells are essential for gas exchange, repair, and regeneration of distal lung epithelium. We have shown that the causative agent, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and other members of the ß-coronavirus genus induce an endoplasmic reticulum (ER) stress response in vitro; however, the consequences for host AT2 cell function in vivo are less understood. To study this, two murine models of coronavirus infection were used-mouse hepatitis virus-1 (MHV-1) in A/J mice and a mouse-adapted SARS-CoV-2 strain. MHV-1-infected mice exhibited dose-dependent weight loss with histological evidence of distal lung injury accompanied by elevated bronchoalveolar lavage fluid (BALF) cell counts and total protein. AT2 cells showed evidence of both viral infection and increased BIP/GRP78 expression, consistent with activation of the unfolded protein response (UPR). The AT2 UPR included increased inositol-requiring enzyme 1α (IRE1α) signaling and a biphasic response in PKR-like ER kinase (PERK) signaling accompanied by marked reductions in AT2 and BALF surfactant protein (SP-B and SP-C) content, increases in surfactant surface tension, and emergence of a reprogrammed epithelial cell population (Krt8+ and Cldn4+). The loss of a homeostatic AT2 cell state was attenuated by treatment with the IRE1α inhibitor OPK-711. As a proof-of-concept, C57BL6 mice infected with mouse-adapted SARS-CoV-2 demonstrated similar lung injury and evidence of disrupted surfactant homeostasis. We conclude that lung injury from ß-coronavirus infection results from an aberrant host response, activating multiple AT2 UPR stress pathways, altering surfactant metabolism/function, and changing AT2 cell state, offering a mechanistic link between SARS-CoV-2 infection, AT2 cell biology, and acute respiratory failure.NEW & NOTEWORTHY COVID-19 syndrome is characterized by hypoxemic respiratory failure and high mortality. In this report, we use two murine models to show that ß-coronavirus infection produces acute lung injury, which results from an aberrant host response, activating multiple epithelial endoplasmic reticular stress pathways, disrupting pulmonary surfactant metabolism and function, and forcing emergence of an aberrant epithelial transition state. Our results offer a mechanistic link between SARS-CoV-2 infection, AT2 cell biology, and respiratory failure.

Differential expression of cellular prion protein (PrPC) in mouse hepatitis virus induced neuroinflammation.

The cellular prion protein (PrPC) is an extracellular cell membrane protein. Due to its diversified roles, a definite role of PrPC has been difficult to establish. During viral infection, PrPC has been reported to play a pleiotropic role. Here, we have attempted to envision the function of PrPC in the neurotropic m-CoV-MHV-RSA59-induced model of neuroinflammation in C57BL/6 mice. A significant upregulation of PrPC at protein and mRNA levels was evident in infected mouse brains during the acute phase of neuroinflammation. Furthermore, investigation of the effect of MHV-RSA59 infection on PrPC expression in specific neuronal, microglial, and astrocytoma cell lines, revealed a differential expression of prion protein during neuroinflammation. Additionally, siRNA-mediated downregulation of prnp transcripts reduced the expression of viral antigen and viral infectivity in these cell lines. Cumulatively, our results suggest that PrPC expression significantly increases during acute MHV-RSA59 infection and that PrPC also assists in viral infectivity and viral replication.

Comparative analysis of liver resection in Non-B Non-C and hepatitis virus-associated hepatocellular carcinoma.

BACKGROUND: The incidence of non-hepatitis B and non-hepatitis C hepatocellular carcinoma (NBNC-HCC) is increasing in our country. This study assesses the feasibility of employing an identical surgical treatment strategy for resectable NBNC-HCC as that for hepatitis virus-associated HCC (HV-HCC). METHODS: A retrospective analysis (1993-2023) of 1321 curative liver resections for HCC at a single institution was performed. Propensity score matching ensured a balanced comparison of preoperative clinical factors, including tumor status and background liver condition. RESULTS: The proportion of NBNC-HCC cases has gradually increased, reaching up to 70 %. After matching, 294 of 473 NBNC-HCC patients and 294 of 848 HV-HCC patients were compared. Operative outcomes, including operation time, blood loss, type of surgical procedure, and morbidity, were comparable. Long-term outcome analysis showed similar recurrence-free survival (HR: 0.86, 95 % CI: 0.70-1.06, P = 0.167) and overall survival (HR: 0.98, 95 % CI: 0.79-1.23, P = 0.865) for NBNC-HCC. Multivariable analysis identified ICGR15 ≥ 15 %, ALBI grade 2 or 3, aspartate aminotransferase ≥40, tumor size > 5 cm, multiple tumors, macrovascular invasion, and microvascular invasion as independent prognostic factors for overall survival, while hepatitis B or C virus status lost significance. CONCLUSIONS: Despite the increasing incidence of NBNC-HCC, comparable outcomes were achieved between the two groups of matched cohort.

Epidemiology, therapy and outcome of hepatocellular carcinoma between 2010 and 2019 in Piedmont, Italy.

BACKGROUND: Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and the second leading cause of cancer deaths worldwide. It is often diagnosed at an advanced stage and therefore its prognosis remains poor with a low 5-year survival rate. HCC patients have increasingly complex and constantly changing characteristics, thus up-to-date and comprehensive data are fundamental. AIM: To analyze the epidemiology and main clinical characteristics of HCC patients in a referral center hospital in the northwest of Italy between 2010 and 2019. METHODS: In this retrospective study, we analyzed the clinical data of all consecutive patients with a new diagnosis of HCC recorded at "Santa Croce e Carle" Hospital in Cuneo (Italy) between 1 January 2010 and 31 December 2019. To highlight possible changes in HCC patterns over the 10-year period, we split the population into two 5-year groups, according to the diagnosis period (2010-2014 and 2015-2019). RESULTS: Of the 328 HCC patients who were included (M/F 255/73; mean age 68.9 ± 11.3 years), 154 in the first period, and 174 in the second. Hepatitis C virus infection was the most common HCC risk factor (41%, 135 patients). The alcoholic etiology rate was 18%, the hepatitis B virus infection etiology was 5%, and the non-viral/non-alcoholic etiology rate was 22%. The Child-Pugh score distribution of the patients was: class A 75%, class B 21% and class C 4%. The average Mayo end-stage liver disease score was 10.6 ± 3.7. A total of 55 patients (17%) were affected by portal vein thrombosis and 158 (48%) by portal hypertension. The average nodule size of the HCC was 4.6 ± 3.1 cm. A total of 204 patients (63%) had more than one nodule < 3, and 92% (305 patients) had a non-metastatic stage of the disease. The Barcelona Clinic Liver Cancer (BCLC) staging distribution of all patients was: 4% very early, 32% early, 23% intermediate, 34% advanced, and 7% terminal. Average survival rate was 1.6 ± 0.3 years. Only 20% of the patients underwent treatment. Age, presence of ascites, BCLC stage and therapy were predictors of a better prognosis (P < 0.01). A comparison of the two 5-year groups revealed a statistically significant difference only in global etiology (P < 0.05) and alpha-fetoprotein (AFP) levels (P < 0.01). CONCLUSION: In this study analyzing patients with a new diagnosis of HCC between 2010-2019, hepatitis C virus infection was the most common etiology. Most patients presented with an advanced stage disease and a poor prognosis. When comparing the two 5-year groups, we observed a statistically significant difference only in global etiology (P < 0.05) and AFP levels (P < 0.01).

Obesity fosters severe disease outcomes in a mouse model of coronavirus infection associated with transcriptomic abnormalities.

Obesity has been identified as an independent risk factor for severe outcomes in humans with coronavirus disease 2019 (COVID-19) and other infectious diseases. Here, we established a mouse model of COVID-19 using the murine betacoronavirus, mouse hepatitis virus 1 (MHV-1). C57BL/6 and C3H/HeJ mice exposed to MHV-1 developed mild and severe disease, respectively. Obese C57BL/6 mice developed clinical manifestations similar to those of lean controls. In contrast, all obese C3H/HeJ mice succumbed by 8 days postinfection, compared to a 50% mortality rate in lean controls. Notably, both lean and obese C3H/HeJ mice exposed to MHV-1 developed lung lesions consistent with severe human COVID-19, with marked evidence of diffuse alveolar damage (DAD). To identify early predictive biomarkers of worsened disease outcomes in obese C3H/HeJ mice, we sequenced RNA from whole blood 2 days postinfection and assessed changes in gene and pathway expression. Many pathways uniquely altered in obese C3H/HeJ mice postinfection aligned with those found in humans with severe COVID-19. Furthermore, we observed altered gene expression related to the unfolded protein response and lipid metabolism in infected obese mice compared to their lean counterparts, suggesting a role in the severity of disease outcomes. This study presents a novel model for studying COVID-19 and elucidating the mechanisms underlying severe disease outcomes in obese and other hosts.

Immunological pathways in viral hepatitis-induced hepato-cellular carcinoma. / è‚ç‚Žç— æ¯’æ„ŸæŸ“å¯¼è‡´è‚ç»†èƒžç™Œå‘ç”Ÿçš„å ç–«æœºåˆ¶ç ”ç©¶è¿›å±•.

Hepatocellular carcinoma (HCC) is a serious neoplastic disease with increasing incidence and mortality, accounting for 90% of all liver cancers. Hepatitis viruses are the major causative agents in the development of HCC. Hepatitis A virus (HAV) primarily causes acute infections, which is associated with HCC to a certain extent, as shown by clinicopathological studies. Chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infections lead to persistent liver inflammation and cirrhosis, disrupt multiple pathways associated with cellular apoptosis and proliferation, and are the most common viral precursors of HCC. Mutations in the HBV X protein (HBx) gene are closely associated with the incidence of HCC, while the expression of HCV core proteins contributes to hepatocellular lipid accumulation, thereby promoting tumorigenesis. In the clinical setting, hepatitis D virus (HDV) frequently co-infects with HBV, increasing the risk of chronic hepatitis. Hepatitis E virus (HEV) usually causes acute infections. However, chronic infections of HEV have been increasing recently, particularly in immuno-compromised patients and organ transplant recipients, which may increase the risk of progression to cirrhosis and the occurrence of HCC. Early detection, effective intervention and vaccination against these viruses may significantly reduce the incidence of liver cancer, while mechanistic insights into the interplay between hepatitis viruses and HCC may facilitate the development of more effective intervention strategies. This article provides a comprehensive overview of hepatitis viruses and reviews recent advances in research on aberrant hepatic immune responses and the pathogenesis of HCC due to viral infection.

Dermatologic Changes in Experimental Model of Long COVID.

The coronavirus disease-19 (COVID-19) pandemic, declared in early 2020, has left an indelible mark on global health, with over 7.0 million deaths and persistent challenges. While the pharmaceutical industry raced to develop vaccines, the emergence of mutant severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) strains continues to pose a significant threat. Beyond the immediate concerns, the long-term health repercussions of COVID-19 survivors are garnering attention, particularly due to documented cases of cardiovascular issues, liver dysfunction, pulmonary complications, kidney impairments, and notable neurocognitive deficits. Recent studies have delved into the pathophysiological changes in various organs following post-acute infection with murine hepatitis virus-1 (MHV-1), a coronavirus, in mice. One aspect that stands out is the impact on the skin, a previously underexplored facet of long-term COVID-19 effects. The research reveals significant cutaneous findings during both the acute and long-term phases post-MHV-1 infection, mirroring certain alterations observed in humans post-SARS-CoV-2 infection. In the acute stages, mice exhibited destruction of the epidermal layer, increased hair follicles, extensive collagen deposition in the dermal layer, and hyperplasticity of sebaceous glands. Moreover, the thinning of the panniculus carnosus and adventitial layer was noted, consistent with human studies. A long-term investigation revealed the absence of hair follicles, destruction of adipose tissues, and further damage to the epidermal layer. Remarkably, treatment with a synthetic peptide, SPIKENET (SPK), designed to prevent Spike glycoprotein-1 binding with host receptors and elicit a potent anti-inflammatory response, showed protection against MHV-1 infection. Precisely, SPK treatment restored hair follicle loss in MHV-1 infection, re-architected the epidermal and dermal layers, and successfully overhauled fatty tissue destruction. These promising findings underscore the potential of SPK as a therapeutic intervention to prevent long-term skin alterations initiated by SARS-CoV-2, providing a glimmer of hope in the battle against the lingering effects of the pandemic.

Silver Nanoparticles In Situ Synthesized and Incorporated in Uniaxial and Core-Shell Electrospun Nanofibers to Inhibit Coronavirus.

In the present study, we sought to develop materials applicable to personal and collective protection equipment to mitigate SARS-CoV-2. For this purpose, AgNPs were synthesized and stabilized into electrospinning nanofiber matrices (NMs) consisting of poly(vinyl alcohol) (PVA), chitosan (CHT), and poly-ε-caprolactone (PCL). Uniaxial nanofibers of PVA and PVA/CHT were developed, as well as coaxial nanofibers of PCL[PVA/CHT], in which the PCL works as a shell and the blend as a core. A crucial aspect of the present study is the in situ synthesis of AgNPs using PVA as a reducing and stabilizing agent. This process presents few steps, no additional toxic reducing agents, and avoids the postloading of drugs or the posttreatment of NM use. In general, the in situ synthesized AgNPs had an average size of 11.6 nm, and the incorporated nanofibers had a diameter in the range of 300 nm, with high uniformity and low polydispersity. The NM's spectroscopic, thermal, and mechanical properties were appropriate for the intended application. Uniaxial (PVA/AgNPs and PVA/CHT/AgNPs) and coaxial (PCL[PVA/CHT/AgNPs]) NMs presented virucidal activity (log's reduction ≥ 5) against mouse hepatitis virus (MHV-3) genus Betacoronavirus strains. In addition to that, the NMs did not present cytotoxicity against fibroblast cells (L929 ATCC® CCL-1TM lineage).

Long-term trends in incidence, mortality and burden of liver cancer due to specific etiologies in Hubei Province.

Liver cancer, a chronic non-communicable disease, represents a serious public health problem. Long-term trends in the burden of liver cancer disease are heterogeneous across regions. Incidence and mortality of liver cancer, based on the Global Burden of Disease, were collected from the Chinese Centre for Disease Control and Prevention. Age-period-cohort model was utilized to reveal the secular trends and estimate the age, period and cohort effects on primary liver cancer due to specific etiologies. Both the age-standardized incidence and mortality rate of liver cancer in Hubei province were on the rise, although there were discrepancies between gender groups. From age-period-cohort analysis, both incidence and mortality of liver cancer due to Hepatitis B virus were the highest in all age groups. The incidence of all liver cancer groups increased with time period in males, while this upward trend was observed in females only in liver cancer due to alcohol use group. Cohort effects indicated the disease burden of liver cancer decreased with birth cohorts. Local drifts showed that the incidence of liver cancer due to specific etiologies was increasing in the age group of males between 40 and 75 years old. The impact of an aging population will continue in Hubei Province. the disease burden of liver cancer will continue to increase, and personalized prevention policies must be adopted to address these changes.

Antigen non-specific CD8+ T cells accelerate cognitive decline in aged mice following respiratory coronavirus infection.

Primarily a respiratory infection, numerous patients infected with SARS-CoV-2 present with neurologic symptoms, some continuing long after viral clearance as a persistent symptomatic phase termed "long COVID". Advanced age increases the risk of severe disease, as well as incidence of long COVID. We hypothesized that perturbations in the aged immune response predispose elderly individuals to severe coronavirus infection and post-infectious sequelae. Using a murine model of respiratory coronavirus, mouse hepatitis virus strain A59 (MHV-A59), we found that aging increased clinical illness and lethality to MHV infection, with aged animals harboring increased virus in the brain during acute infection. This was coupled with an unexpected increase in activated CD8+ T cells within the brains of aged animals but reduced antigen specificity of those CD8+ T cells. Aged animals demonstrated spatial learning impairment following MHV infection, which correlated with increased neuronal cell death and reduced neuronal regeneration in aged hippocampus. Using primary cell culture, we demonstrated that activated CD8+ T cells induce neuronal death, independent of antigen-specificity. Specifically, higher levels of CD8+ T cell-derived IFN-γ correlated with neuronal death. These results support the evidence that CD8+ T cells in the brain directly contribute to cognitive dysfunction following coronavirus infection in aged individuals.

Analysis of the molecular determinants for furin cleavage of the spike protein S1/S2 site in defined strains of the prototype coronavirus murine hepatitis virus (MHV).

We analyzed the spike protein S1/S2 cleavage of selected strains of a prototype coronavirus, mouse hepatitis virus (MHV) by the cellular protease furin, in order to understand the structural requirements underlying the sequence selectivity of the scissile segment. The probability of cleavage of selected MHV strains was first evaluated from furin cleavage scores predicted by the ProP computer software, and then cleavage was measured experimentally with a fluorogenic peptide cleavage assay consisting of S1/S2 peptide mimics and purified furin. We found that in vitro cleavability varied across MHV strains in line with predicted results-but with the notable exception of MHV-A59, which was not cleaved despite a high score predicted for its sequence. Using the known X-Ray structure of furin in complex with a substrate-like inhibitor as an initial structural reference, we carried out molecular dynamics (MD) simulations to learn the modes of binding of the peptides in the furin active site, and the suitability of the complex for initiation of the enzymatic cleavage. We identified the 3D structural requirements of the furin active site configuration that enable bound peptides to undergo cleavage, and the way in which the various strains tested experimentally are fulfilling these requirements. We find that despite some flexibility in the organization of the peptide bound to the active site of the enzyme, the presence of a histidine at P2 of MHV-A59 fails to properly orient the sidechain of His194 of the furin catalytic triad and therefore produces a distortion that renders the peptide/complex structural configuration in the active site incompatible with requirements for cleavage initiation. The Ser/Thr in P1 of MHV-2 and MHV-S has a similar effect of distorting the conformation of the furin active site residues produced by the elimination of the canonical salt-bridge formed by arginine in P1 position. This work informs a study of coronavirus infection and pathogenesis with respect to the function of the viral spike protein, and suggests an important process of viral adaptation and evolution within the spike S1/S2 structural loop.

The association between periodontitis and hepatitis virus infection: a cross-sectional study utilizing data from the NHANES database (2003-2018).

OBJECTIVES: Periodontitis and hepatitis virus infection significantly impact individuals' well-being and are prevalent public health concerns globally. Given the current scarcity of large-scale cross-sectional epidemiological studies, this study seeks to enrich the evidence base by examining the link between these two conditions. STUDY DESIGN AND METHODS: A cross-sectional study was conducted using data from the National Health and Nutrition Examination Survey (NHANES) spanning the years 2003-2018. A multivariate logistic regression analysis was performed to assess the association between periodontitis and hepatitis virus infection, adjusting for the potential confounding factors. Subsequently, a stratified analysis was conducted to explore the relationship between periodontitis and hepatitis virus infection based on age, gender, race, marital status, alcohol consumption, smoking status, and the presence of chronic diseases. RESULTS: In this study, which included 5755 participants, there was a positive association between hepatitis virus infection and periodontitis (odds ratio [OR]: 2.609 [95% confidence interval (CI): 1.513, 4.499]). Furthermore, a significant association was observed between moderate periodontitis and hepatitis virus infection (OR: 2.136 [95% CI: 1.194, 3.822]), and this association was even stronger for severe periodontitis (OR: 3.583 [95% CI: 1.779, 7.217]). Importantly, this positive association between hepatitis virus infection and periodontitis was consistent across different subgroups. CONCLUSIONS: This study presents evidence of a significant association between periodontitis and hepatitis virus infection. These findings highlight the crucial importance of integrating periodontal health and liver health considerations into public health interventions. Further research is necessary to elucidate the underlying mechanisms and develop targeted interventions for effectively managing periodontitis and hepatitis virus infection.